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Spexin (SPX) is a 14-amino-acid peptide that plays an important role in the regulation of metabolism and energy homeostasis. It is well known that a variety of bioactive molecules released into the circulation by organs and tissues in response to acute and chronic exercise, known as exerkines, mediate the benefits of exercise by improving metabolic health. However, it is unclear whether acute exercise affects SPX levels in the circulation and peripheral tissues. This study aimed to determine whether acute treadmill exercise induces plasma SPX levels, as well as mRNA expression and immunostaining of SPX in skeletal muscle, adipose tissue, and liver. Male Sprague Dawley rats were divided into sedentary and acute exercise groups. Plasma, soleus (SOL), extensor digitorum longus (EDL), adipose tissue, and liver samples were collected at six time points (0, 1, 3, 6, 12, and 24 h) following 60 min of acute treadmill exercise at a speed of 25 m/min and 0 % grade. Acute exercise increased plasma SPX levels and induced mRNA expression of Spx in the SOL, EDL, and liver. Immunohistochemical analysis demonstrated that acute exercise led to a decrease in SPX immunostaining in the liver. Taken together, these findings suggest that SPX increases in response to acute exercise as a potential exerkine candidate, and the liver may be one of the sources of acute exercise-induced plasma SPX levels in rats. However, a comprehensive analysis is needed to fully elucidate the systemic response of SPX to acute exercise, as well as the tissue from which SPX is secreted., Competing Interests: Declaration of Competing Interest The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Phoenixin (PNX) is a conserved secreted peptide that was identified 10 years ago with numerous studies published on its pleiotropic functions. PNX is associated with estrous cycle length, protection from a high-fat diet, and reduction of anxiety behavior. However, no study had yet evaluated the impact of deleting PNX in the whole animal. We sought to evaluate a mouse model lacking the PNX parent gene, small integral membrane protein 20 (Smim20), and the resulting effect on reproduction, energy homeostasis, and anxiety. We found that the Smim20 knockout mice had normal fertility and estrous cycle lengths. Consistent with normal fertility, the hypothalamii of the knockout mice showed no changes in the levels of reproduction-related genes, but the male mice had some changes in energy homeostasis-related genes, such as melanocortin receptor 4 (Mc4r). When placed on a high-fat diet, the wildtype and knockout mice responded similarly, but the male heterozygous mice gained slightly less weight. When placed in an open field test box, the female knockout mice traveled less distance in the outer zone, indicating alterations in anxiety or locomotor behavior. In summary, the homozygous knockout of PNX did not alter fertility and modestly alters a few neuroendocrine genes in response to a high-fat diet, especially in the female mice. However, it altered the behavior of mice in an open field test. PNX therefore may not be crucial for reproductive function or weight, however, we cannot rule out possible compensatory mechanisms in the knockout model. Understanding the role of PNX in physiology may ultimately lead to an enhanced understanding of neuroendocrine mechanisms involving this enigmatic peptide., (© 2024 The Authors. Journal of Neuroendocrinology published by John Wiley & Sons Ltd on behalf of British Society for Neuroendocrinology.)

The corpus luteum (CL) is a temporary endocrine gland that synthesizes progesterone. The luteal progesterone plays a central role in the regulation of the estrous cycle as well as the implantation and maintenance of pregnancy. Our previous study showed the expression of adropin and its receptor, GPR19, in the luteal cells and its significant role in luteinization. The aim of the present study was to investigate the in vitro effect of adropin on hCG-induced ovarian functions in adult mice. We also evaluated the effect of exogenous treatment with adropin on ovarian steroidogenesis and anti-oxidant parameters, with special emphasis on CL function. Our results demonstrated that adropin acts synergistically with hCG to promote ovarian steroidogenesis and survival by increasing the expression of StAR, 3β-HSD, and aromatase proteins and decreasing the BAX/BCL2 ratio. Exogenous adropin treatment increased progesterone production by increasing the expression of GPR19, StAR and 3β-HSD enzymes in the mouse ovary. Also, adropin inhibited the luteal oxidative stress by increasing nuclear translocation of NRF-2 in CL, which resulted in increased HO-1 expression and SOD, catalase activity. Decreased oxidative stress might inhibit the translocation of NF-κB into the nucleus of luteal cells, resulting into increased survival and decreased apoptosis, as evident by decreased lipid peroxidation, BAX/BCL2 ratio, caspase 3, active caspase 3 expression, and TUNEL-positive cells in adropin treated mice. Our findings suggest that adropin can be a promising candidate that can enhance the survivability of the CL., Competing Interests: Declaration of Competing interest The authors declare that there are no conflicts of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Vascular smooth muscle cell (VSMCs) is one of the important cell types in artery. VSMCs stiffening may regulate vascular stiffness and contribute to the development of vulnerable plaques. Thrombin, an enzyme in coagulation system, is involved in pathological processes of atherosclerosis. Inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) plays an important role in regulating inflammation and may have cardiovascular protective effect. Therefore, the elucidation of the mechanisms underlying ITIH4-mediated VSMCs stiffening helps to provide new ideas and potential targets for the diagnosis and treatment of atherosclerosis. In this study, we used specific ITIH4 expression vector and siRNA methods to transfect VSMCs. Our results found that ITIH4 expression increased VSMCs stiffness, meanwhile, ITIH4 siRNA decreased VSMCs stiffness. ITIH4 increased acetylated α-tubulin and inhibited ERK1/2 and JNK, but not P38 MAPK. ERK inhibitor (PD98059) or JNK inhibitor (SP600125) treatment increased acetylated α-tubulin expression and cell stiffness in VSMCs. ITIH4 was downregulated by thrombin treatment, ITIH4 partly reversed the effect of thrombin on acetylated α-tubulin and VSMCs stiffness. These results indicated that ITIH4 regulated acetylated α-tubulin expression in VSMCs and was against the effects of thrombin on VSMCs stiffness. JNK and ERK signaling pathways were proved to participate in this process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Angiopoietin-like protein 8 (ANGPTL8) is an important regulator of lipid metabolism. We aimed to investigate the difference of ANGPTL8 expression in different depots of adipose tissues between individuals with and without obesity, and its correlation with various metabolic parameters., Methods: Subcutaneous (SAT) and visceral adipose tissue (VAT) samples were collected from patients who underwent bariatric or intra-abdominal surgery. Expression levels of ANGPTL8, monoglyceride lipase (MGL), monocyte chemoattractant protein-1 (MCP-1), leptin and adiponectin (APM1) were determined using real-time quantitative polymerase chain reaction. The correlation of ANGPTL8 expression with various metabolic parameters and other gene expression levels was analyzed using Person's correlation analysis. Logistic regression was used to establish a prediction model of obesity., Results: Totally 330 subjects (obese: 281, non-obese: 49) were recruited. ANGPTL8 expression in VAT was significantly higher in the obesity group than in the non-obesity group (P = 0.0096). ANGPTL8 expression in VAT was positively correlated with body mass index (BMI) (r = 0.1169, P < 0.05) and was independently associated with obesity (O.R., 1.246; 95 % C.I. 1.013-21.533, P = 0.038). We also found the gene expression of ANGPTL8 in SAT and VAT was negatively correlated with APM1 expression in respective SAT and VAT., Conclusion: ANGPTL8 expression levels in VAT were higher in subjects with obesity, and positively correlated with BMI. This suggests a role of ANGPTL8 in the pathophysiology of obesity and may pave the way for novel treatment target of obesity., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2023 Formosan Medical Association. Published by Elsevier B.V. All rights reserved.)

Background: Coronary artery disease (CAD) is the leading cause of death worldwide despite advanced treatment and diagnosis strategies. Angiopoietin-like protein 8 (ANGPTL8) mainly functions in the lipid mechanism, which is a dysregulated mechanism during CAD pathogenesis. In this study, we aimed to determine the associations between an ANGPTL8 polymorphism rs2278426 and the severity, presence, and risk factors of CAD., Methods: A total of 1367 unrelated Turkish individuals who underwent coronary angiography were recruited for the study and grouped as CAD (n = 736, ≥50 stenosis) and non-CAD (n = 549, ≤30 stenosis). Also, subjects were further divided into groups regarding type 2 diabetes mellitus (T2DM) status. Subjects were genotyped for rs2278426 (C/T) by quantitative real-time PCR. Secondary structure analyses of protein interactions were revealed using I-TASSER and PyMOL., Results: Among CAD patients, T allele carriage frequency was lower in the T2DM group (p = 0.046). Moreover, in male non-CAD group, T allele carriage was more prevalent among T2DM patients than non-T2DM (p = 0.033). In logistic regression analysis adjusted for obesity, T allele carrier males had an increased risk for T2DM in non-CAD group (OR = 2.244, 95 % CI: 1.057-4.761, p = 0.035). Also, in T2DM group, stenosis (p = 0.002) and SYNTAX score (p = 0.040) were lower in T allele carrier males than in non-carriers. Analyzes of secondary structure showed that ANGPTL8 could not directly form complexes with ANGPTL3 or ANGPTL4., Conclusion: In conclusion, T allele carriage of ANGPTL8 rs2278426 has a protective effect on CAD in T2DM patients. Further research should be conducted to explore the association between ANGPTL8 polymorphism (rs2778426) and CAD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

C-terminally encoded peptides (CEPs) are peptide hormones that function as mobile signals coordinating crucial developmental programs in plants. Previous studies have revealed that CEPs exert negative regulation on root development through interaction with CEP receptors (CEPRs), CEP DOWNSTREAMs (CEPDs), the cytokinin receptor ARABIDOPSIS HISTIDINE KINASE (AHKs) and the transcriptional repressor Auxin/Indole-3-Acetic Acid (AUX/IAA). However, the precise molecular mechanisms underlying CEPs-mediated regulation of root development via auxin and cytokinin signaling pathways still necessitate further detailed investigation. In this study, we examined prior research and elucidated the underlying molecular mechanisms. The results showed that both synthetic AtCEPs and overexpression of AtCEP5 markedly supressed primary root elongation and lateral root (LR) formation in Arabidopsis. Molecular biology and genetics elucidated how CEPs inhibit root growth by suppressing auxin signaling while promoting cytokinin signaling. In summary, this study elucidated the inhibitory effects of AtCEPs on Arabidopsis root growth and provided insights into their potential molecular mechanisms, thus enhancing our comprehension of CEP-mediated regulation of plant growth and development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Unlike other poultry, parent pigeons produce "pigeon milk" in their crops to nurture their squabs, which is mainly controlled by prolactin (PRL). Exception for PRL, the pituitary gland may also release various other peptide and protein hormones. However, whether these hormones change during pigeon crop lactation and their potential physiological functions remain unclear. Here, to identify potential peptide or protein hormone genes that regulate crop lactation, we conducted transcriptome analysis of pigeon pituitary glands at 3 different breeding stages (the ceased stage-nonincubation and non-nurturing stage, the 11th d of the incubation, and the 1st d of the nurturing stage) using RNA sequencing (RNA-Seq). Our analysis identified a total of 15,191 mRNAs and screened out 297 differentially expressed genes (DEG), including PRL, VIP, etc. The expression abundance of PRL mRNA on the 1st d of the nurturing stage was respectively 4.93 and 3.62 folds higher when compared to the ceased stage and the 11th d of the incubation stage. Additionally, the expression abundance of VIP is higher in the 1st d of the nurturing stage than in the ceased stage. Protein-protein interaction (PPI) network and Molecular Complex Detection (MCODE) analysis identified several vital DEGs (e.g., GHRHR, VIP, etc.), being closely linked with hormone and enriched in neuropeptide signaling pathway and response to the hormone. Expression pattern analysis revealed that these DEGs exhibited 4 distinct expression patterns (profile 10, 16, 18, 19). Genes in profile 10 and 19 presented a trend with the highest expression level on 1st d of the nurturing stage, and functional enrichment analysis indicated that these genes are involved in neuropeptide hormone activity, receptor-ligand activity, and the extracellular matrix, etc. Taken together, being consistent with PRL, some genes encoding peptide and protein hormones (e.g., VIP) presented differentially expressed in different breeding stages. It suggests that these hormones may be involved in regulation of the crop lactation process or corresponding behavior in domestic pigeons. The results of this study help to gain new insights into the role of pituitary gland in regulating pigeon lactation., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

C-TERMINALLY ENCODED PEPTIDEs ( CEPs ) are a class of peptide hormones that have been shown in previous studies to play an important role in regulating the development and response to abiotic stress in model plants. However, their role in cotton is not well understood. In this study, we identified 54, 59, 34, and 35 CEP genes from Gossypium hirsutum (2n = 4x = 52, AD1), G. barbadense (AD2), G. arboreum (2n = 2X = 26, A2), and G. raimondii (2n = 2X = 26, D5), respectively. Sequence alignment and phylogenetic analyses indicate that cotton CEP proteins can be categorized into two subgroups based on the differentiation of their CEP domain. Chromosomal distribution and collinearity analyses show that most of the cotton CEP genes are situated in gene clusters, suggesting that segmental duplication may be a critical factor in CEP gene expansion. Expression pattern analyses showed that cotton CEP genes are widely expressed throughout the plant, with some genes exhibiting specific expression patterns. Ectopic expression of GhCEP46-D05 in Arabidopsis led to a significant reduction in both root length and seed size, resulting in a dwarf phenotype. Similarly, overexpression of GhCEP46-D05 in cotton resulted in reduced internode length and plant height. These findings provide a foundation for further investigation into the function of cotton CEP genes and their potential role in cotton breeding.

The mechanism of fish gonadal sex differentiation is complex and regulated by multiple factors. It has been widely known that proper steroidogenesis in Leydig cells and sex-related genes in Sertoli cells play important roles in gonadal sex differentiation. In teleosts, the precise interaction of these signals during the sexual fate determination remains elusive, especially their effect on the bi-potential gonad during the critical stage of sexual fate determination. Recently, all-testis phenotypes have been observed in the cyp17a1 -deficient zebrafish and common carp, as well as in cyp19a1a -deficient zebrafish. By mating cyp17a1 -deficient fish with transgenic zebrafish Tg(piwil1:EGFP-nanos3UTR) , germ cells in the gonads were labelled with enhanced green fluorescent protein (EGFP). We classified the cyp17a1 -deficient zebrafish and their control siblings into primordial germ cell (PGC)-rich and -less groups according to the fluorescence area of the EGFP labelling. Intriguingly, the EGFP-labelled bi-potential gonads in cyp17a1 +/+ fish from the PGC-rich group were significantly larger than those of the cyp17a1 -/- fish at 23 days post-fertilization (dpf). Based on the transcriptome analysis, we observed that the cyp17a1 -deficient fish of the PGC-rich group displayed a significantly upregulated expression of amh and gsdf compared to that of control fish. Likewise, the upregulated expressions of amh and gsdf were observed in cyp19a1a -deficient fish as examined at 23 dpf. This upregulation of amh and gsdf could be repressed by treatment with an exogenous supplement of estradiol. Moreover, tamoxifen, an effective antagonist of both estrogen receptor α and β (ERα and Erβ), upregulates the expression of amh and gsdf in wild-type (WT) fish. Using the cyp17a1 - and cyp19a1a -deficient zebrafish, we provide evidence to show that the upregulated expression of amh and gsdf due to the compromised estrogen signaling probably determines their sexual fate towards testis differentiation. Collectively, our data suggest that estrogen signaling inhibits the expression of amh and gsdf during the critical time of sexual fate determination, which may broaden the scope of sex steroid hormones in regulating gonadal sex differentiation in fish.

Hepcidin, a peptide hormone that negatively regulates iron metabolism, is expressed by bone morphogenetic protein (BMP) signaling. Erythroferrone (ERFE) is an extracellular protein that binds and inhibits BMP ligands, thus positively regulating iron import by indirectly suppressing hepcidin. This allows for rapid erythrocyte regeneration after blood loss. ERFE belongs to the C1Q/TNF-related protein family and is suggested to adopt multiple oligomeric forms: a trimer, a hexamer, and a high molecular weight species. The molecular basis for how ERFE binds BMP ligands and how the different oligomeric states impact BMP inhibition are poorly understood. In this study, we demonstrated that ERFE activity is dependent on the presence of stable dimeric or trimeric ERFE and that larger species are dispensable for BMP inhibition. Additionally, we used an in silico approach to identify a helix, termed the ligand-binding domain, that was predicted to bind BMPs and occlude the type I receptor pocket. We provide evidence that the ligand-binding domain is crucial for activity through luciferase assays and surface plasmon resonance analysis. Our findings provide new insight into how ERFE oligomerization impacts BMP inhibition, while identifying critical molecular features of ERFE essential for binding BMP ligands., Competing Interests: Conflict of interest T. B. T. is a consultant/advisor for Keros Therapeutics and Oviva Therapeutics. All other authors declare they have no conflicts of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Iron delivery to the plasma is closely coupled to erythropoiesis, the production of red blood cells, as this process consumes most of the circulating plasma iron. In response to hemorrhage and other erythropoietic stresses, increased erythropoietin stimulates the production of the hormone erythroferrone (ERFE) by erythrocyte precursors (erythroblasts) developing in erythropoietic tissues. ERFE acts on the liver to inhibit bone morphogenetic protein (BMP) signaling and thereby decrease hepcidin production. Decreased circulating hepcidin concentrations then allow the release of iron from stores and increase iron absorption from the diet. Guided by evolutionary analysis and Alphafold2 protein complex modeling, we used targeted ERFE mutations, deletions, and synthetic ERFE segments together with cell-based bioassays and surface plasmon resonance to probe the structural features required for bioactivity and BMP binding. We define the ERFE active domain and multiple structural features that act together to entrap BMP ligands. In particular, the hydrophobic helical segment 81 to 86 and specifically the highly conserved tryptophan W82 in the N-terminal region are essential for ERFE bioactivity and Alphafold2 modeling places W82 between two tryptophans in its ligands BMP2, BMP6, and the BMP2/6 heterodimer, an interaction similar to those that bind BMPs to their cognate receptors. Finally, we identify the cationic region 96-107 and the globular TNFα-like domain 186-354 as structural determinants of ERFE multimerization that increase the avidity of ERFE for BMP ligands. Collectively, our results provide further insight into the ERFE-mediated inhibition of BMP signaling in response to erythropoietic stress., Competing Interests: Conflict of interest T. G. and E. N. are shareholders and scientific advisors of Intrinsic LifeSciences and consultants for Ionis Pharmaceuticals, Disc Medicine, Silence Therapeutics Chugai, and Vifor. E. N. is a consultant for Protagonist, and T. G. is a consultant for Akebia, Dexcel, and Avidity Bio. Other authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Angiopoietin-like protein 8 (ANGPTL8) is known to regulate lipid metabolism and inflammation. It interacts with ANGPTL3 and ANGPTL4 to regulate lipoprotein lipase (LPL) activity and with IKK to modulate NF-κB activity. Further, a single nucleotide polymorphism (SNP) leading to the ANGPTL8 R59W variant associates with reduced low-density lipoprotein/high-density lipoprotein (LDL/HDL) and increased fasting blood glucose (FBG) in Hispanic and Arab individuals, respectively. In this study, we investigate the impact of the R59W variant on the inflammatory activity of ANGPTL8., Methods: The ANGPTL8 R59W variant was genotyped in a discovery cohort of 867 Arab individuals from Kuwait. Plasma levels of ANGPTL8 and inflammatory markers were measured and tested for associations with the genotype; the associations were tested for replication in an independent cohort of 278 Arab individuals. Impact of the ANGPTL8 R59W variant on NF-κB activity was examined using approaches including overexpression, luciferase assay, and structural modeling of binding dynamics., Results: The ANGPTL8 R59W variant was associated with increased circulatory levels of tumor necrosis factor alpha (TNFα) and interleukin 7 (IL7). Our in vitro studies using HepG2 cells revealed an increased phosphorylation of key inflammatory proteins of the NF-κB pathway in individuals with the R59W variant as compared to those with the wild type, and TNFα stimulation further elevated it. This finding was substantiated by increased luciferase activity of NF-κB p65 with the R59W variant. Modeled structural and binding variation due to R59W change in ANGPTL8 agreed with the observed increase in NF-κB activity., Conclusion: ANGPTL8 R59W is associated with increased circulatory TNFα, IL7, and NF-κB p65 activity. Weak transient binding of the ANGPTL8 R59W variant explains its regulatory role on the NF-κB pathway and inflammation.

Asprosin, encoded by penultimate two exons (exon 65 and exon 66) of the gene Fibrillin 1 (FBN1), has been recently discovered to be a novel hormone secreted by white adipose tissues during fasting. The glucose metabolism disorders are often accompanied by increased asprosin level. Previous research suggests that asprosin may contribute to the development of diabetes by regulating glucose homeostasis, appetite, insulin secretion, and insulin sensitivity. In this review, we summarize the recent findings from studies on asprosin and its association with Type 2 diabetes mellitus, and discusses its mechanisms from various aspects, so as to provide clinical diagnosis and treatment ideas for T2DM., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest regarding the publication of this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Apelin and Elabela (Ela) are peptides encoded by APLN and APELA, respectively, which act on their receptor APJ and play crucial roles in the body. Recent research has shown that they not only have important effects on the endocrine system, but also promote vascular development and maintain the homeostasis of myocardial cells. From a molecular biology perspective, we explored the roles of Ela and apelin in the cardiovascular system and summarized the mechanisms of apelin-APJ signaling in the progression of myocardial infarction, ischemia-reperfusion injury, atherosclerosis, pulmonary arterial hypertension, preeclampsia, and congenital heart disease. Evidences indicated that apelin and Ela play important roles in cardiovascular diseases, and there are many studies focused on developing apelin, Ela, and their analogues for clinical treatments. However, the literature on the therapeutic potential of apelin, Ela and their analogues and other APJ agonists in the cardiovascular system is still limited. This review summarized the regulatory pathways of apelin/ELA-APJ axis in cardiovascular function and cardiovascular-related diseases, and the therapeutic effects of their analogues in cardiovascular diseases were also included., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2023. Published by Elsevier Masson SAS.)

Peptide hormones influence diverse aspects of plant development through highly coordinated cell-cell signaling pathways. Many peptide hormone families play key roles in stem cell maintenance across land plants. In this review, we focus on recent work in two conserved peptide hormone families, CLAVATA3/EMBRYO-SURROUNDING REGION (CLEs) and ROOT MERISTEM GROWTH FACTOR (RGFs), and their roles in regulating plant stem cells. We discuss recent work establishing downstream crosstalk between peptide hormones and other conserved signaling mechanisms in meristem maintenance as well as highlight advances in peptide hormone gene identification that provide important context for CLE/RGF family evolution across diverse plant lineages. CLE and RGF gene families have greatly expanded in angiosperms, contributing to the complex genetic regulation of stem cell homeostasis observed in model systems over the last 30 years. Peptide hormone duplications have resulted in genetic compensation mechanisms that ensure robust development through the function of paralogous genes. Broad conservation of genetic compensation across angiosperms highlights the importance of these mechanisms in developmental signaling and understanding their regulation could inform broader understanding of morphological diversity and evolutionary innovation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Neuropeptides and peptide hormones are ancient, widespread signaling molecules that underpin almost all brain functions. They constitute a broad ligand-receptor network, mainly by binding to G protein-coupled receptors (GPCRs). However, the organization of the peptidergic network and roles of many peptides remain elusive, as our insight into peptide-receptor interactions is limited and many peptide GPCRs are still orphan receptors. Here we report a genome-wide peptide-GPCR interaction map in Caenorhabditis elegans. By reverse pharmacology screening of over 55,384 possible interactions, we identify 461 cognate peptide-GPCR couples that uncover a broad signaling network with specific and complex combinatorial interactions encoded across and within single peptidergic genes. These interactions provide insights into peptide functions and evolution. Combining our dataset with phylogenetic analysis supports peptide-receptor co-evolution and conservation of at least 14 bilaterian peptidergic systems in C. elegans. This resource lays a foundation for system-wide analysis of the peptidergic network., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Nonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disease with a global prevalence, and modulation of ANGPTL8 expression has emerged as a promising predictor of NAFLD susceptibility. This research was conducted to scrutinize ANGPTL8 protein expression in NAFLD patients and elucidate the interplay between ANGPTL8 gene polymorphisms and their lipid profiles, thus shedding new light on the pathophysiology of this complex disease. The study comprised 423 unrelated participants, including 222 healthy controls and 201 individuals with NAFLD, screened using FibroScan/ultrasonography and laboratory tests. The main goal focused on the genotype and allele frequency distribution in the ANGPTL8 gene, specifically analyzing two genetic variations: rs737337 (T/C) and rs2278426 (C/T). The participants diagnosed with NAFLD were slightly younger (P ≥ 0.05) and had a higher body mass index (BMI) than the individuals in the control group. Notably, there was a significant difference in the occurrence of the rs737337 polymorphism between the NAFLD and control groups, with a lower frequency observed in the NAFLD group. Our results indicated that individuals with the TC + CC genotype and C allele of rs737337 (T/C) had a decreased risk of higher levels of ALT and AST. Conversely, those with the CT, CT + TT genotype, and T allele of rs2278426 (C/T) exhibited an increased risk of higher levels of ALT and AST. The results imply that the rs2278426 (C/T) variant of the ANGPTL8 gene is more strongly linked to an increased risk of NAFLD compared to the rs737337 polymorphism. However, additional research is needed to understand the specific molecular mechanisms responsible for the upregulation of ANGPTL8 in individuals with NAFLD., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Angiopoietin-like protein 8 (ANGPTL8) plays important roles in lipid metabolism, glucose metabolism, inflammation, and cell proliferation and migration. Clinical studies have indicated that circulating ANGPTL8 levels are increased in patients with thoracic aortic dissection (TAD). TAD shares several risk factors with abdominal aortic aneurysm (AAA). However, the role of ANGPTL8 in AAA pathogenesis has never been investigated. Here, we investigated the effect of ANGPTL8 knockout on AAA in ApoE-/- mice. ApoE-/-ANGPTL8-/- mice were generated by crossing ANGPTL8-/- and ApoE-/- mice. AAA was induced in ApoE-/- using perfusion of angiotensin II (AngII). ANGPTL8 was significantly up-regulated in AAA tissues of human and experimental mice. Knockout of ANGPTL8 significantly reduced AngII-induced AAA formation, elastin breaks, aortic inflammatory cytokines, matrix metalloproteinase expression, and smooth muscle cell apoptosis in ApoE-/- mice. Similarly, ANGPTL8 sh-RNA significantly reduced AngII-induced AAA formation in ApoE-/- mice. ANGPTL8 deficiency inhibited AAA formation, and ANGPTL8 may therefore be a potential therapeutic target for AAA., (© 2023 The Author(s).)

Angiopoietin-like proteins (ANGPTL) constitute a family of eight proteins (1-8) which play a pivotal role in the regulation of various pathophysiological processes. The current study sought to identify high-risk, "non-synonymous, single-nucleotide polymorphisms" (nsSNPs) in both ANGPTL3 and ANGPTL8 to evaluate the role that these nsSNPs play in various types of cancer. We retrieved a total of 301 nsSNPs from various databases; 79 of these candidates constitute high-risk nsSNPs. Moreover, we identified eleven high-risk nsSNPs that cause various types of cancer: seven candidates for ANGPTL3 (L57H, F295L, L309F, K329M, R332L, S348C, and G409R) and four candidates for ANGPTL8 (P23L, R85W, R138S, and E148D). Protein-protein interaction analysis revealed a strong association of ANGPTL proteins with several tumor-suppressor proteins such as ITGB3, ITGAV, and RASSF5. 'Gene-expression profiling interactive analysis' (GEPIA) showed that expression of ANGPTL3 is significantly downregulated in five cancers: sarcoma (SARC); cholangio carcinoma (CHOL); kidney chromophobe carcinoma (KICH); kidney renal clear cell carcinoma (KIRC); and kidney renal papillary cell carcinoma (KIRP). GEPIA also showed that expression of ANGPTL8 remains downregulated in three cancers: CHOL; glioblastoma (GBM); and breast invasive carcinoma (BRCA). Survival rate analysis indicated that both upregulation and downregulation of ANGPTL3 and ANGPTL8 leads to low survival rates in various types of cancer. Overall, the current study revealed that both ANGPTL3 and ANGPTL8 constitute potential prognostic biomarkers for cancer; moreover, nsSNPs in these proteins might lead to the progression of cancer. However, further in vivo investigation will be helpful to validate the role of these proteins in the biology of cancer.

Rationale: Ischemia-reperfusion injury (I/R) is a common cause of acute kidney injury (AKI). Post-ischemic recovery of renal blood supply plays an important role in attenuating injury. Exogenous application of elabela (ELA) peptides has been demonstrated by us and others to alleviate AKI, partly through its receptor APJ. However, the endogenous role of ELA in renal I/R remains unclear. Methods: Renal tubule specific ELA knockout ( Apela Ksp KO) mice challenged with bilateral or unilateral I/R were used to investigate the role of endogenous ELA in renal I/R. RNA-sequencing analysis was performed to unbiasedly investigate altered genes in kidneys of Apela Ksp KO mice. Injured mice were treated with ELA32 peptide, Nω-hydroxy-nor-L-arginine (nor-NOHA), prostaglandin E2 (PGE2), Paricalcitol, ML221 or respective vehicles, individually or in combination. Results: ELA is mostly expressed in renal tubules. Aggravated pathological injury and further reduction of renal microvascular blood flow were observed in Apela Ksp KO mice during AKI and the following transition to chronic kidney disease (AKI-CKD). RNA-seq analysis suggested that two blood flow regulators, arginine metabolizing enzyme arginase 2 (ARG2) and PGE2 metabolizing enzyme carbonyl reductases 1 and 3 (CBR1/3), were altered in injured Apela Ksp KO mice. Notably, combination application of an ARG2 inhibitor nor-NOHA, and Paricalcitol, a clinically used activator for PGE2 synthesis, alleviated injury-induced AKI/AKI-CKD stages and eliminated the worst outcomes observed in Apela Ksp KO mice. Moreover, while the APJ inhibitor ML221 blocked the beneficial effects of ELA32 peptide on AKI, it showed no effect on combination treatment of nor-NOHA and Paricalcitol. Conclusions: An endogenous tubular ELA-APJ axis regulates renal microvascular blood flow that plays a pivotal role in I/R-induced AKI. Furthermore, improving renal blood flow by inhibiting ARG2 and activating PGE2 is an effective treatment for AKI and prevents the subsequent AKI-CKD transition., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Background: Pulmonary artery hypertension (PAH) is a common disease that seriously threatens human physical and mental health. Chronic obstructive pulmonary disease (COPD) is the main cause of secondary PAH., Objectives: This study observed the differential expression of the endogenous Apela/APJ system in COPD patients with or without PAH., Methods: A total of 69 COPD patients were enrolled, including 31 patients with PAH (COPD+PAH). Lung tissue from healthy controls, COPD patients, and COPD patients with PAH was used for RT-PCR and histological examination., Results: The serum level of endogenous Apela in COPD+PAH patients was significantly lower than those in the control and COPD groups. Correlation analysis showed that systolic pulmonary artery pressure in COPD+PAH patients was negatively correlated with the serum level of endogenous Apela (r = -0.3842, p < 0.05). The percentage of intima thickening and muscularization of pulmonary arterioles was increased in COPD+PAH patients, while the expression of Apela/APJ was decreased. Compared with the healthy controls and COPD patients, the expression of endothelial markers vWF and CD34 mRNA in the pulmonary arterioles in COPD+PAH patients decreased, while the expression of interstitial markers α-SMA and vimentin mRNA was up-regulated., Conclusion: The present study suggests that expression of the Apela/APJ system is decreased in PAH secondary to COPD. The pathological changes involved in PAH secondary to COPD include thickening of the intima and muscularization of the pulmonary arterioles, as well as endothelial-to-mesenchymal transition. Corrective action targeting the diminished Apela/APJ system may be a promising therapeutic strategy for PAH in the future., Competing Interests: Declaration of Competing Interest The authors declare no any conflicts of interest in this work., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Objectives: The present study sought to examine the relationship of betatrophin with certain key enzymes, namely lactate dehydrogenase-5 (LDH5), citrate synthase (CS), and acetyl-CoA carboxylase-1 (ACC1), in insulin-resistant mice., Methods: Eight-week-old male C57BL6/J mice were used in this study (experimental group n=10 and control group n=10). S961 was administered using an osmotic pump to induce insulin resistance in the mice. The betatrophin, LDH5, CS, and ACC1 expression levels were determined from the livers of the mice using the real-time polymerase chain reaction (RT-PCR) method. Moreover, biochemical parameters such as the serum betatrophin, fasting glucose, insulin, triglyceride, total cholesterol, and high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol levels were analyzed., Results: The betatrophin expression and serum betatrophin (p=0.000), fasting glucose, insulin, triglyceride (p≤0.001), and total cholesterol (p=0.013) levels were increased in the experimental group. In addition, the CS gene expression level was statistically significantly decreased in the experimental group (p=0.01). Although strong correlation was found between the expression and serum betatrophin and triglyceride levels, no correlation was found between the betatrophin gene expression and the LDH5, ACC1, and CS gene expression levels., Conclusions: The betatrophin level appears to play an important role in the regulation of triglyceride metabolism, while insulin resistance increases both the betatrophin gene expression and serum levels and decreases the CS expression level. The findings suggest that betatrophin may not regulate carbohydrate metabolism through CS and LDH5 or lipid metabolism directly through the ACC1 enzyme., (© 2023 Walter de Gruyter GmbH, Berlin/Boston.)

Introduction: Hypercholesterolemia is a chronic noncommunicable disease predisposing to cardiovascular diseases. Genome‑wide association studies have shown that more than 500 common nucleotide variants are associated with dyslipidemia., Objectives: We evaluated associations between selected nucleotide variants in ANGPTL6, DOCK6, FABP1, and PCSK9 genes and hypercholesterolemia in the Polish adult population sample., Patients and Methods: The study included 109 patients with hypercholesterolemia and 251 individuals with no diagnosed lipid disorder. Genotyping of ANGPTL6 rs8112063, DOCK6 rs737337 and rs17699089, FABP1 rs2241883 and rs2919872, and PCSK9 rs562556 and rs11206510 was carried out using highresolution melting curve analysis. Serum concentrations of FABP1, PCSK9, ANGPTL6, and ANGPTL8 were determined in 51 individuals by enzyme‑linked immunosorbent assay., Results: Carriers of the FABP1 rs2919872 CC genotype were over 2.5‑fold less likely to be diagnosed with hypercholesterolemia than carriers of the T allele (odds ratio [OR], 0.386; 95% CI, 0.203-0.735; P = 0.003; Pcorr = 0.006). There were no associations between rs2919872 and serum lipid concentrations. Carriers of the ANGPTL6 rs8112063 C allele had an almost 2‑fold higher risk of developing hypercholesterolemia than carriers of the T allele (OR, 1.820; 95% CI, 1.053-3.144; P = 0.03; Pcorr = 0.046). Moreover, the carriers of the ANGPTL6 rs8112063 C allele had higher serum concentrations of high-density lipoprotein cholesterol than those with TT genotype (P = 0.009). There were no significant associations between the other tested variants and hypercholesterolemia., Conclusions: FABP1 rs2919872 and ANGPTL6 rs8112063 are associated with a risk of hypercholesterolemia in the Polish population.

Somatic embryogenesis (SE) is widely used for studying the mechanisms of embryo development. However, little is known about the underlying mechanisms, especially in woody plants. Previous studies have established an SE system for Chinese fir (Cunninghamia lanceolata), but this system is genotype-dependent, which limits its application in practice. Here, we found that phytosulfokine (PSK), a plant peptide hormone, can not only increase SE efficiency, but also establish SE in recalcitrant genotypes of C. lanceolata. Proembryogenic mass (PEM) browning and determination of hydrogen peroxide (H 2 O 2 ) content by 2',7'-dichlorofluorescein staining indicated that a reactive oxygen species (ROS) burst occurred rapidly after PEMs were transferred to SE induction medium. Transcriptome analysis and quantitative reverse transcriptase-PCR validation showed that PSK treatment helped to maintain ROS homeostasis by decreasing the activity of peroxidases in early SE induction. This PSK-regulated redox microenvironment might be helpful to induce expression of SE-related genes like WOX2 in early SE induction. Further analyses suggested that PSK promotes SE induction in C. lanceolata partially through decreasing H 2 O 2 levels, which is necessary but not sufficient for SE induction in recalcitrant genotypes of C. lanceolata. Furthermore, heterologous overexpression of ClPSK in Arabidopsis led to enhanced SE induction and resistance to H 2 O 2 stress. Taken together, our study reveals a biological function for the plant peptide hormone PSK, extends our knowledge about SE in woody trees, and provides a valuable tool for establishing an efficient and genotype-independent SE system in C. lanceolata and other coniferous trees., (© 2022 Society for Experimental Biology and John Wiley & Sons Ltd.)

The erythroferrone gene ( ERFE ), also termed CTRP15 , belongs to the C1q tumor necrosis factor-related protein (CTRP) family. Despite multiple reports about the involvement of CTRPs in cancer, the role of ERFE in cancer progression is largely unknown. We previously found that ERFE was upregulated in erythroid progenitors in myelodysplastic syndromes and strongly predicted overall survival. To understand the potential molecular interactions and identify cues for further functional investigation and the prognostic impact of ERFE in other malignancies, we performed a pan-cancer in silico analysis utilizing the Cancer Genome Atlas datasets. Our analysis shows that the ERFE mRNA is significantly overexpressed in 22 tumors and affects the prognosis in 11 cancer types. In certain tumors such as breast cancer and adrenocortical carcinoma, ERFE overexpression has been associated with the presence of oncogenic mutations and a higher tumor mutational burden. The expression of ERFE is co-regulated with the factors and pathways involved in cancer progression and metastasis, including activated pathways of the cell cycle, extracellular matrix/tumor microenvironment, G protein-coupled receptor, NOTCH, WNT, and PI3 kinase-AKT. Moreover, ERFE expression influences intratumoral immune cell infiltration. Conclusively, ERFE is aberrantly expressed in pan-cancer and can potentially function as a prognostic biomarker based on its putative functions during tumorigenesis and tumor development.

Angiopoietin-like proteins, ANGPTL3, ANGPTL4, and ANGPTL8, are involved in regulating plasma lipids. In vitro and animal-based studies point to LPL and endothelial lipase (EL, LIPG) as key targets of ANGPTLs. To examine the ANGPTL mechanisms for plasma lipid modulation in humans, we pursued a genetic mimicry analysis of enhancing or suppressing variants in the LPL, LIPG, lipase C hepatic type (LIPC), ANGPTL3, ANGPTL4, and ANGPTL8 genes using data on 248 metabolic parameters derived from over 110,000 nonfasted individuals in the UK Biobank and validated in over 13,000 overnight fasted individuals from 11 other European populations. ANGPTL4 suppression was highly concordant with LPL enhancement but not HL or EL, suggesting ANGPTL4 impacts plasma metabolic parameters exclusively via LPL. The LPL-independent effects of ANGPTL3 suppression on plasma metabolic parameters showed a striking inverse resemblance with EL suppression, suggesting ANGPTL3 not only targets LPL but also targets EL. Investigation of the impact of the ANGPTL3-ANGPTL8 complex on plasma metabolite traits via the ANGPTL8 R59W substitution as an instrumental variable showed a much higher concordance between R59W and EL activity than between R59W and LPL activity, suggesting the R59W substitution more strongly affects EL inhibition than LPL inhibition. Meanwhile, when using a rare and deleterious protein-truncating ANGPTL8 variant as an instrumental variable, the ANGPTL3-ANGPTL8 complex was very LPL specific. In conclusion, our analysis provides strong human genetic evidence that the ANGPTL3-ANGPTL8 complex regulates plasma metabolic parameters, which is achieved by impacting LPL and EL. By contrast, ANGPTL4 influences plasma metabolic parameters exclusively via LPL., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

RAPID ALKALINIZATION FACTORs (RALFs), which are secreted peptides serving as extracellular signals transduced to the inside of the cell, interact with the receptor-like kinase FERONIA (FER) and participates in various biological pathways. Here, we identified 23 RALF and 2 FER genes in Hevea brasiliensis (para rubber tree), and characterized their expression patterns in different tissues, across the process of leaf development, and in response to the rubber yield-stimulating treatments of tapping and ethylene. Four Hevea latex (the cytoplasm of rubber-producing laticifers)-abundant RALF isoforms, HbRALF19, HbRALF3, HbRALF22, and HbRALF16 were listed with descending expression levels. Of the four HbRALFs, expressions of HbRALF3 were markedly regulated in an opposite way by the treatments of tapping (depression) and ethylene (stimulation). All of the four latex-abundant RALFs specifically interacted with the extracellular domain of HbFER1. Transgenic Arabidopsis plants overexpressing these HbRALFs displayed phenotypes similar to those reported for AtRALFs, such as shorter roots, smaller plant architecture, and delayed flowering. The application of HbRALF3 and HbRALF19 recombinant proteins significantly reduced the pH of Hevea latex, an important factor regulating latex metabolism. An in vitro rubber biosynthesis assay in a mixture of latex cytosol (C-serum) revealed a positive role of HbFER1 in rubber biosynthesis. Taken together, these data provide evidence for the participation of the HbRALF-FER module in rubber production., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background: Plant growth and development are complex processes modulated by numerous genes, transcription factors, hormones, and peptides. Several reports implicate the membrane-localized Catharanthus roseus receptor-like kinase1 (CrRLK1L) protein, FERONIA (FER), involved in plant development. However, protein targets of FER remain poorly characterized., Objective: FER recombinant proteins were analyzed, and FER-interacting proteins were identified, to better understand the function of the Arabidopsis thaliana FER (AtFER) gene in plant development., Methods: AtFER-interacting proteins were identified through Yeast-Two Hybrid (Y2H) and validated by bimolecular fluorescence complementation (BiFC). Autophosphorylation activity was evaluated in AtFER site-directed and deletion mutants., Results: AtFER cytoplasmic kinase domain (Flag-FER-CD) is autophosphorylated at the Thr residue (s), with T559 and T664 as important sites for AtFER kinase activity. In addition, the carboxy terminal region is essential for AtFER kinase activity. Y2H identified an Armadillo (ARM)-repeat protein (At4g16490) with tandem copies of a degenerate protein sequence motif, a U-BOX 9 (PUB9, At3g07360), IQ-DOMAIN 7 (IQD7, At1g17480), and heteroglycan glucosidase 1 (HGL1, At3g23640) as AtFER-interacting proteins. BiFC confirmed the in vivo interactions between these four proteins and AtFER in tobacco (Nicotiana benthamiana) leaf transient expression assays. The RAPID ALKALINIZATION FACTOR1 (RALF1) peptide, which is a FER ligand, induced the expression of genes encoding the four AtFER-interacting proteins., Conclusion: The AtFER-interacting proteins identified in this study are likely involved in FER-mediated intracellular signaling pathways that are essential in plant growth and development, and possibly plant immunity., (© 2022. The Author(s) under exclusive licence to The Genetics Society of Korea.)

In multicellular organisms, endocrine factors such as hormones and cytokines regulate development and homoeostasis through communication between different organs. For understanding such interorgan communications through endocrine factors, the fruit fly Drosophila melanogaster serves as an excellent model system due to conservation of essential endocrine systems between flies and mammals and availability of powerful genetic tools. In Drosophila and other insects, functions of neuropeptides or peptide hormones from the central nervous system have been extensively studied. However, a series of recent studies conducted in Drosophila revealed that peptide hormones derived from peripheral tissues also play critical roles in regulating multiple biological processes, including growth, metabolism, reproduction, and behaviour. Here, we summarise recent advances in understanding target organs/tissues and functions of peripherally derived peptide hormones in Drosophila and describe how these hormones contribute to various biological events through interorgan communications.

Thyroid cancer is associated with genetic alterations, e.g. BRAF V600E , which may cause carcinomatous changes in hormone-secreting epithelial cells. Epidemiological studies have shown that overnutrition is related to the development and progression of cancer. In this study, we attempted to identify the cell nonautonomous factor responsible for the progression of BRAF V600E thyroid cancer under overnutrition conditions. We developed a mouse model for inducible thyrocyte-specific activation of BRAF V600E , which showed features similar to those of human papillary thyroid cancer. LSL-Braf V600E ;TgCreER T2 showed thyroid tumour development in the entire thyroid, and the tumour showed more abnormal cellular features with mitochondrial abnormalities in mice fed a high-fat diet (HFD). Transcriptomics revealed that adrenomedullin2 (Adm2) was increased in LSL-Braf V600E ;TgCreER T2 mice fed HFD. ADM2 was upregulated on the addition of a mitochondrial complex I inhibitor or palmitic acid with integrated stress response (ISR) in cancer cells. ADM2 stimulated protein kinase A and extracellular signal-regulated kinase in vitro. The knockdown of ADM2 suppressed the proliferation and migration of thyroid cancer cells. We searched The Cancer Genome Atlas and Genotype-Tissue Expression databases and found that increased ADM2 expression was associated with ISR and poor overall survival. Consistently, upregulated ADM2 expression in tumour cells and circulating ADM2 molecules were associated with aggressive clinicopathological parameters, including body mass index, in thyroid cancer patients. Collectively, we identified that ADM2 is released from cancer cells under mitochondrial stress resulting from overnutrition and acts as a secretory factor determining the progressive properties of thyroid cancer. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland., (© 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.)

As a major complication after percutaneous coronary intervention (PCI) in patients who suffer from coronary artery disease, in-stent restenosis (ISR) poses a significant challenge for clinical management. A miRNA-mRNA regulatory network of ISR can be constructed to better reveal the occurrence of ISR. The relevant data set from the Gene Expression Omnibus (GEO) database was downloaded, and 284 differentially expressed miRNAs (DE-miRNAs) and 849 differentially expressed mRNAs (DE-mRNAs) were identified. As predicted by online tools, 65 final functional genes (FmRNAs) were overlapping DE-mRNAs and DE-miRNAs target genes. In the biological process (BP) terms of gene ontology (GO) functional analysis, the FmRNAs were mainly enriched in the cellular response to peptide, epithelial cell proliferation, and response to peptide hormone. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the FmRNAs were mainly enriched in breast cancer, endocrine resistance, and Cushing syndrome. Jun proto-oncogene, activator protein-1 (AP-1) transcription factor subunit ( JUN ), insulin-like growth factor 1 receptor ( IGF1R ), member RAS oncogene family ( RAB14 ), specificity protein 1 ( SP1 ), protein tyrosine phosphatase nonreceptor type 1 ( PTPN1 ), DDB1 and CUL4 associated factor 10 ( DCAF10 ), retinoblastoma-binding protein 5 ( RBBP5 ), and eukaryotic initiation factor 4A-I ( EIF4A1 ) were hub genes in the protein-protein interaction network (PPI network). The miRNA-mRNA network containing DE-miRNAs and hub genes was built. Hsa-miR-139-5p- JUN , hsa-miR-324-5p- SP1 axis pairs were found in the miRNA-mRNA network, which could promote ISR development. The aforementioned results indicate that the miRNA-mRNA network constructed in ISR has a regulatory role in the development of ISR and may provide new approaches for clinical treatment and experimental development.

Purpose: Breast cancer is the most frequently diagnosed cancer and is the leading cause of cancer-associated mortality in women worldwide. Intermedin (IMD, also known as Adrenomedullin 2, ADM2) is an endogenous peptide that belongs to the calcitonin gene-related peptide family and has been reported to play important roles in several types of cancers, including breast cancer. In this study, we sought to investigate how IMD affects the behavior of breast cancer cells, the underlying mechanism of these effects, and whether blockade of IMD has a therapeutic effect against breast cancer., Methods: Transcriptome sequencing (RNA-Seq), cell biological experiments, Western blotting, immunoprecipitation, and animal tumor models were used., Results: IMD expression was significantly increased in breast cancer samples, and the IMD level was positively correlated with lymph node metastasis and Ki67 expression. Cell biological experiments showed that IMD promoted the anchorage-independent growth, migration, and invasive ability of breast cancer cells. Inhibiting IMD activity with an anti-IMD monoclonal antibody blocked these tumor-promoting effects. In addition, blockade of IMD reduced in situ tumor growth and significantly decreased lung metastasis of 4T1 breast cancer in vivo. IMD induced Src kinase phosphorylation, which triggered the transcription of c-Myc, a major oncoprotein controlling the expression of genes that encode ribosomal components. Our data suggest that IMD is involved in breast cancer cell invasion and metastasis, potentially through increasing ribosome biogenesis and protein translation via the Src/c-Myc signaling pathway., Conclusion: These results suggest that IMD may be a novel target for the treatment of breast cancer., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Pathological cardiac hypertrophy is an independent risk factor for heart failure and is considered a target for the treatment of heart failure. However, the mechanisms underlying pathological cardiac hypertrophy remain largely unknown. We aimed to investigate the role of angiopoietin-like protein 8 (ANGPTL8) in pathological cardiac hypertrophy. We found that serum ANGPTL8 levels were significantly increased in hypertensive patients with cardiac hypertrophy and in mice with cardiac hypertrophy induced by Ang II or TAC. Furthermore, the secretion of ANGPTL8 from the liver was increased during hypertrophic processes, which were triggered by Ang II. In the Ang II- and transverse aortic constriction (TAC)-induced mouse cardiac hypertrophy model, ANGPTL8 deficiency remarkably accelerated cardiac hypertrophy and fibrosis with deteriorating cardiac dysfunction. Accordingly, both recombinant human full-length ANGPTL8 (rANGPTL8) protein and ANGPTL8 overexpression significantly mitigated Ang II-induced cell enlargement in primary neonatal rat cardiomyocytes (NRCMs) and H9c2 cells. Mechanistically, the antihypertrophic effects of ANGPTL8 depended on inhibiting Akt and GSK-3β activation, and the Akt activator SC-79 abolished the antihypertrophic effects of rANGPTL8 in vitro. Moreover, we demonstrated that ANGPTL8 directly bound to the paired Ig-like receptor PIRB (LILRB3) by RNA-seq and immunoprecipitation-mass screening. Remarkably, the antihypertrophic effects of ANGPTL8 were largely blocked by anti-LILRB3 and siRNA-LILRB3. Our study indicated that ANGPTL8 served as a novel negative regulator of pathological cardiac hypertrophy by binding to LILRB3 (PIRB) and inhibiting Akt/GSK3β activation, suggesting that ANGPTL8 may provide synergistic effects in combination with AT1 blockers and become a therapeutic target for cardiac hypertrophy and heart failure., (© 2022. The Author(s).)

Spexin (SPX) is a novel peptide involved in glucose and lipid metabolism and suppresses hepatic total bile acid levels by inhibiting hepatic cholesterol 7α-hydroxylase 1 expression. As important mediators for glycolysis/gluconeogenesis and lipid metabolism, the effects of bile acids on SPX expression is yet to be understood. By using SMMC7721 and BEL-7402 cell lines, we screened the effects of bile acids and found that chenodeoxycholic acid (CDCA) and deoxycholic acid (DCA) can stimulate SPX gene transcription. Both CDCA and DCA were able to stimulate SPX mRNA expression in the liver but not colon and ileum in mice. In SMMC7721 and BEL-7402 cells, CDCA- and DCA-induced SPX promoter activity was mimicked by bile acid receptor FXR and TGR5 activation and suppressed by FXR and TGR5 silencing. Adenylate cyclase (AC)/cyclic adenosine monophosphate (cAMP) activators significantly increased SPX promoter activity whereas the inhibitors for AC/CAMP/protein kinase A (PKA) and mitogen-activated protein kinases (MAPK) pathway attenuated CDCA- and DCA-induced SPX transcription. Thus, CDCA and DCA stimulate SPX expression at the hepatic level through FXR and TGR5 mediated AC/cAMP/PKA and MAPK cascades.

Background: The aim of this study was to explore the function and mechanism of GKN1 in gastric cancer (GC) progression., Methods: Firstly, we used GEO2R to perform differential gene analysis on GSE26942 and GSE79973 and constructed the protein-protein interaction network of differential genes by STRING. Next, the cytoHubba, Mcode plugins, and GEPIA were used to obtain our follow-up research object GKN1. Then, the function of GKN1 in GC was verified by scratch and transwell assay in GC cells. We further analyzed the genes related to GKN1 through LinkedOmics, and exported top 100 genes positively or negatively correlated with GKN1. Meanwhile, Metascape was performed on these genes. Finally, we analyzed the miRNAs that bind to GKN1 through the miRDB and verified the correlation between miR-548d-3p and GKN1 using dual-fluorescence and quantitative PCR experiments., Results: Bioinformatics analysis showed that there were 52 differential genes on GSE26942 and GSE79973. In addition, the results of functional assays indicated that overexpressed GKN1 can inhibit GC cell migration and invasion, while GKN1 knockdown demonstrated the opposite effect. Additionally, Metascape analysis results showed that the 3'-UTR region of mRNA is rich in AU sequences, based on which we infer that mRNA may be regulated by miRNA. Dual-fluorescence and quantitative PCR assays clarified that miR-548d-3p may be one of the target miRNAs of GKN1, which was up-regulated in GC tissues., Conclusions: In summary, we clarified that miR-548d-3p regulates GKN1 to participate in GC cell migration and invasion, and provides a possible target for the prognostic diagnosis and treatment of GC., (© 2022 The Authors. Journal of Clinical Laboratory Analysis published by Wiley Periodicals LLC.)

Gene expression of the chick retina was examined during the early development of lens-induced myopia (LIM) using whole transcriptome sequencing. Monocular treatment of the right eyes with -10 diopter (D) lenses was performed on newly born chicks for one day (LIM-24) or two days (LIM-48), while the contralateral eyes without lenses served as controls. Myopia development was confirmed by demonstrating significant elongation of the optical axis in lens-treated eyes compared to untreated control eyes. RNA was extracted and RNA-seq was performed using the Illumina HiSeq TM 2000 platform. Data analysis was carried out on a Partek® Flow platform. Using screening criteria of ≥1.30-fold change and a false discovery rate <1%, 11 (five down-regulated and six up-regulated) and 35 differentially expressed genes (six down-regulated and twenty-nine up-regulated) were identified at 24 hours and 48 hours, respectively. Using another cohort for validation, Quantitative PCR confirmed significant changes in the expression of VIP and UTS2B mRNA ( P <0.05) after only 24 hours of LIM treatment and numerical changes in the expression for PCGF5 and FOXG1 , which were consistent with transcriptome sequencing but did not reach statistical significance. These data suggest that concerted changes of retinal gene expression may be instrumental in the initiation of axial elongation and myopia development.

Enteroendocrine cells (EECs) are the primary sensory cells that sense the gut luminal environment and secret hormones to regulate organ function. Recent studies revealed that vagal afferent neurons are connected to EECs and relay sensory information from EECs to the brain stem. To date, however, the identity of vagal afferent neurons connected to a given EEC subtype and the mode of their gene responses to its intestinal hormone have remained unknown. Hypothesizing that EEC-associated vagal afferent neurons change their gene expression in response to the microbiota-related extracellular stimuli, we conducted comparative gene expression analyses of the nodose-petrosal ganglion complex (NPG) using specific pathogen-free (SPF) and germ-free (GF) mice. We report here that the Uts2b gene, which encodes a functionally unknown neuropeptide, urotensin 2B (UTS2B), is expressed in a microbiota-dependent manner in NPG neurons. In cultured NPG neurons, expression of Uts2b was induced by AR420626, the selective agonist for FFAR3. Moreover, distinct gastrointestinal hormones exerted differential effects on Uts2b expression in NPG neurons, where cholecystokinin (CCK) significantly increased its expression. The majority of Uts2b-expressing NPG neurons expressed CCK-A, the receptor for CCK, which comprised approximately 25% of all CCK-A-expressing NPG neurons. Selective fluorescent labeling of Uts2b-expressing NPG neurons revealed a direct contact of their nerve fibers to CCK-expressing EECs. This study identifies the Uts2b as a microbiota-regulated gene, demonstrates that Uts2b-expressing vagal afferent neurons transduce sensory information from CCK-expressing EECs to the brain, and suggests potential involvement of UTS2B in a modality of CCK actions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Hypertensive disorders of pregnancy (HDPs) are believed to comprise a group of multifactorial genetic diseases. Recently, it was reported that APELA -knockout mice exhibited HDP-like symptoms, including proteinuria and elevated blood pressure due to defective placental angiogenesis. The aim of the present study is to determine the associations between HDPs and single-nucleotide variants or haplotypes in the human APELA gene through a case-control study. The subjects were 196 pregnant women with HDPs and a control group of 254 women without HDPs. Six single-nucleotide variants (rs2068792, rs13120303, rs4541465, rs13152225, rs78639146, and rs67448487) were selected from the APELA gene region. Although there were no significant differences for each single-nucleotide polymorphism in the case-control study, the frequency of the T-A haplotypes rs4541465-rs67448487 was significantly higher in the HDP group, especially in those with gestational hypertension, than in the control group. The results suggest that the APELA gene may be a disease-susceptibility gene for HDP.

Most peptide hormones and growth factors are matured from larger inactive precursor proteins by proteolytic processing and further posttranslational modification. Whether or how posttranslational modifications contribute to peptide bioactivity is still largely unknown. We address this question here for TWS1 (Twisted Seed 1), a peptide regulator of embryonic cuticle formation in Arabidopsis thaliana . Using synthetic peptides encompassing the N- and C-terminal processing sites and the recombinant TWS1 precursor as substrates, we show that the precursor is cleaved by the subtilase SBT1.8 at both the N and the C termini of TWS1. Recognition and correct processing at the N-terminal site depended on sulfation of an adjacent tyrosine residue. Arginine 302 of SBT1.8 was found to be required for sulfotyrosine binding and for accurate processing of the TWS1 precursor. The data reveal a critical role for posttranslational modification, here tyrosine sulfation of a plant peptide hormone precursor, in mediating processing specificity and peptide maturation.

Background and Objectives: Brain arteriovenous malformation (bAVM) is a congenital disorder and a leading cause of hemorrhagic stroke. Germline genetic variants play an essential role in the pathogenesis of bAVM. However, the biological relevance of disease-associated genes identified in previous studies is elusive. In this study, we aim to systematically investigate the contribution of germline variants to bAVM and explore the critical molecular pathways underlying the pathogenesis of bAVM., Methods: Probands with sporadic bAVM were consecutively recruited into this study from November 2015 to November 2018 and underwent exome sequencing. The controls were aggregated from individuals who were not known to have vascular malformation and underwent exome sequencing for clinical or research purposes. The retained control dataset included 4,609 individuals, including 251 individuals with parental samples sequenced. We first analyzed de novo variants in cases and controls and performed a pathway enrichment analysis. A gene-based rare variant association analysis was then performed to identify genes whose variants were significantly enriched in cases., Results: We collected an exome-sequenced bAVM cohort consisting of 152 trios and 40 singletons. By first focusing on de novo variants, we observed a significant mutational burden of likely gene-disrupting variants in cases vs controls. By performing a pathway enrichment analysis of all nonsynonymous de novo variants identified in cases, we found the angiopoietin-like protein 8 (ANGPTL8) regulatory pathway to be significantly enriched in patients with bAVM. Through an exome-wide rare variant association analysis utilizing 4,394 in-house exome data as controls, we identified SLC19A3 as a disease-associated gene for bAVM. In addition, we found that the SLC19A3 variants in cases are preferably located at the N' side of the SLC19A3 protein. These findings implicate a phenotypic expansion of SLC19A3 -related disorders with a domain-specific effect., Discussion: This study provides insights into the biological basis of bAVM by identifying novel molecular pathways and candidate genes., (© 2022 American Academy of Neurology.)

Asprosin is a fasting-induced glucogenic and centrally acting orexigenic hormone. The olfactory receptor Olfr734 is known to be the hepatic receptor for asprosin that mediates its effects on glucose production, but the receptor for asprosin's orexigenic function has been unclear. Here, we have identified protein tyrosine phosphatase receptor δ (Ptprd) as the orexigenic receptor for asprosin. Asprosin functions as a high-affinity Ptprd ligand in hypothalamic AgRP neurons, regulating the activity of this circuit in a cell-autonomous manner. Genetic ablation of Ptprd results in a strong loss of appetite, leanness, and an inability to respond to the orexigenic effects of asprosin. Ablation of Ptprd specifically in AgRP neurons causes resistance to diet-induced obesity. Introduction of the soluble Ptprd ligand-binding domain in the circulation of mice suppresses appetite and blood glucose levels by sequestering plasma asprosin. Identification of Ptprd as the orexigenic asprosin receptor creates a new avenue for the development of anti-obesity therapeutics., Competing Interests: Declaration of interests Atul Chopra has been awarded asprosin-related patents and is a co-founder, director, and officer of Vizigen, Inc. and Aceragen, Inc. and holds equity in both companies. The other authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Unlike constitutively secreted proteins, peptide hormones are stored in densely packed secretory granules, before regulated release upon stimulation. Secretory granules are formed at the TGN by self-aggregation of prohormones as functional amyloids. The nonapeptide hormone vasopressin, which forms a small disulfide loop, was shown to be responsible for granule formation of its precursor in the TGN as well as for toxic fibrillar aggregation of unfolded mutants in the ER. Several other hormone precursors also contain similar small disulfide loops suggesting their function as a general device to mediate aggregation for granule sorting. To test this hypothesis, we studied the capacity of small disulfide loops of different hormone precursors to mediate aggregation in the ER and the TGN. They indeed induced ER aggregation in Neuro-2a and COS-1 cells. Fused to a constitutively secreted reporter protein, they also promoted sorting into secretory granules, enhanced stimulated secretion, and increased Lubrol insolubility in AtT20 cells. These results support the hypothesis that small disulfide loops act as novel signals for sorting into secretory granules by self-aggregation., (© 2022 Reck et al.)

For a long time, Apelin has been considered as the only endogenous ligand of G protein-coupled receptor APJ. Until recently, the discovery of Elabela (Apela/Toddler) as a new polypeptide that can act through APJ and has a similar function to Apelin broke this situation. Elabela promotes a variety of cell proliferation processes, including embryonic development, and has especially beneficial effects in the cardiovascular system. In this review, we summarize the biological functions of Elabela and review its specific roles in cardiovascular diseases and the signaling pathways mediated by it., (Copyright © 2021 Elsevier Inc. All rights reserved.)

SPX (spexin) and its receptors GalR2 and GalR3 (galanin receptor subtype 2 and galanin receptor subtype 3) play an important role in the regulation of lipid and carbohydrate metabolism in human and animal fat tissue. However, little is still known about the role of this peptide in the metabolism of muscle. The aim of this study was to determine the impact of SPX on the metabolism, proliferation and differentiation of the skeletal muscle cell line C2C12. Moreover, we determined the effect of exercise on the SPX transduction pathway in mice skeletal muscle. We found that increased SPX, acting via GalR2 and GalR3 receptors, and ERK1/2 phosphorylation stimulated the proliferation of C2C12 cells ( p < 0.01). We also noted that SPX stimulated the differentiation of C2C12 by increasing mRNA and protein levels of differentiation markers Myh, myogenin and MyoD ( p < 0.01). SPX consequently promoted myoblast fusion into the myotubule ( p < 0.01). Moreover, we found that, in the first stage (after 2 days) of myocyte differentiation, GalR2 and GalR3 were involved, whereas in the last stage (day six), the effect of SPX was mediated by the GalR3 isoform. We also noted that exercise stimulated SPX and GalR2 expression in mice skeletal muscle as well as an increase in SPX concentration in blood serum. These new insights may contribute to a better understanding of the role of SPX in the metabolism of skeletal muscle.

Rooting is a key innovation during plant terrestrialization. RGFs/GLVs/CLELs are a family of secreted peptides, playing key roles in root stem cell niche maintenance and pattern formation. The origin of this peptide family is not well characterized. RGFs and their receptor genes, RGIs , were investigated comprehensively using phylogenetic and genetic analyses. We identified 203 RGF genes from 24 plant species, representing a variety of land plant lineages. We found that the RGF genes originate from land plants and expand via multiple duplication events. The lineage-specific RGF duplicates are retained due to their regulatory divergence, while a majority of RGFs experienced strong purifying selection in most land plants. Functional analysis indicated that RGFs and their receptor genes, RGIs , isolated from liverwort, tomato, and maize possess similar biological functions with their counterparts from Arabidopsis in root development. RGFs and RGIs are likely coevolved in land plants. Our studies shed light on the origin and functional conservation of this important peptide family in plant root development.

Angiopoietin-like protein 8 (ANGPTL8) is an hepatokine altered in several metabolic conditions, such as obesity, type 2 diabetes, dyslipidemia and nonalcoholic fatty liver disease (NAFLD). We sought to explore whether ANGPTL8 is involved in NAFLD amelioration after bariatric surgery in experimental models and patients with severe obesity. Plasma ANGPTL8 was measured in 170 individuals before and 6 months after bariatric surgery. Hepatic ANGPTL8 expression was evaluated in liver biopsies of patients with severe obesity undergoing bariatric surgery with available liver pathology analysis ( n = 75), as well as in male Wistar rats with diet-induced obesity subjected to sham operation, sleeve gastrectomy or Roux-en-Y gastric bypass (RYGB) ( n = 65). The effect of ANGPTL8 on lipogenesis was assessed in human HepG2 hepatocytes under palmitate-induced lipotoxic conditions. Plasma concentrations and hepatic expression of ANGPTL8 were increased in patients with obesity-associated NAFLD in relation to the degree of hepatic steatosis. Sleeve gastrectomy and RYGB improved hepatosteatosis and reduced the hepatic ANGPTL8 expression in the preclinical model of NAFLD. Interestingly, ANGPTL8 inhibited steatosis and expression of lipogenic factors ( PPARG2 , SREBF1 , MOGAT2 and DGAT1 ) in palmitate-treated human hepatocytes. Together, ANGPTL8 is involved in the resolution of NAFLD after bariatric surgery partially by the inhibition of lipogenesis in steatotic hepatocytes.

Over the last decade, the urotensinergic system, composed of one G protein-coupled receptor and two endogenous ligands, has garnered significant attention as a promising new target for the treatment of various cardiovascular diseases. Indeed, this system is associated with various biomarkers of cardiovascular dysfunctions and is involved in changes in cardiac contractility, fibrosis, and hypertrophy contributing, like the angiotensinergic system, to the pathogenesis and progression of heart failure. Significant investment has been made toward the development of clinically relevant UT ligands for therapeutic intervention, but with little or no success to date. This system therefore remains to be therapeutically exploited. Pepducins and other lipidated peptides have been used as both mechanistic probes and potential therapeutics; therefore, pepducins derived from the human urotensin II receptor might represent unique tools to generate signaling bias and study hUT signaling networks. Two hUT-derived pepducins, derived from the second and the third intracellular loop of the receptor (hUT-Pep2 and [Trp 1 , Leu 2 ]hUT-Pep3, respectively), were synthesized and pharmacologically characterized. Our results demonstrated that hUT-Pep2 and [Trp 1 , Leu 2 ]hUT-Pep3 acted as biased ago-allosteric modulators, triggered ERK 1/2 phosphorylation and, to a lesser extent, IP 1 production, and stimulated cell proliferation yet were devoid of contractile activity. Interestingly, both hUT-derived pepducins were able to modulate human urotensin II (hUII)- and urotensin II-related peptide (URP)-mediated contraction albeit to different extents. These new derivatives represent unique tools to reveal the intricacies of hUT signaling and also a novel avenue for the design of allosteric ligands selectively targeting hUT signaling potentially., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

This study was aimed at investigating whether Elabela (ELA) gene therapy can promote angiogenesis in the treatment of myocardial infarction (MI). The fusion expression plasmid pAAV-3 × Flag/ELA-32 was successfully constructed using molecular cloning technique. The model of acute MI was established by ligating the left anterior descending coronary artery in mice. Adeno-associated virus serotype 9 (AAV9) was injected into the surrounding myocardium and tail vein immediately after the model was established. AAV was injected again from the tail vein one week later. Compared with the MI+PBS (control) group, the serum N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration, and the values of left ventricular end-diastolic diameter (LVDd) and left ventricular end-systolic diameter (LVDs) of the MI+AAV-ELA (gene therapy) group were significantly decreased, while the value of left ventricular ejection fraction was significantly increased at 2 and 4 weeks after operation. Compared with the control group, the expression of CD105 and vWF and the percentage of CD31- and Ki67-co-positive cells were significantly increased in the gene therapy group. Moreover, the expressions of apelin peptide jejunum (APJ) receptor, vascular endothelial growth factor (VEGF), VEGFR2, Jagged1 and Notch3 in the heart tissue around the infarction were up-regulated in mice with gene therapy. The results suggest that ELA activates VEFG/VEGFR2 and Jagged1/Notch3 pathways through APJ to promote angiogenesis after myocardial infarction. ELA gene therapy may be used in the treatment of ischaemic cardiomyopathy in future., (© 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Rho GDP-dissociation inhibitor (RhoGDI), a downregulator of Rho family GTPases, prevents nucleotide exchange and membrane association. It is responsible for the activation of Rho GTPases, which regulate a variety of cellular processes, such as migration. Although RhoGDI2 has been identified as a tumor suppressor gene involved in cellular migration and invasion, little is known about its role in vascular endothelial cell (EC) migration. CR6-interacting factor 1 (CRIF1) is a CR6/GADD45-interacting protein with important mitochondrial functions and regulation of cell growth. We examined the expression of RhoGDI2 in CRIF1-deficient human umbilical vein endothelial cells (HUVECs) and its role in cell migration. Expression of RhoGDI2 was found to be considerably higher in CRIF1-deficient HUVECs along with suppression of cell migration. Moreover, the phosphorylation levels of Akt and CREB were decreased in CRIF1-silenced cells. The Akt-CREB signaling pathway was implicated in the changes in endothelial cell migration caused by CRIF1 downregulation. In addition to RhoGDI2, we identified another factor that promotes migration and invasion of ECs. Adrenomedullin2 (ADM2) is an autocrine/paracrine factor that regulates vascular tone and other vascular functions. Endogenous ADM2 levels were elevated in CRIF1-silenced HUVECs with no effect on cell migration. However, siRNA-mediated depletion of RhoGDI2 or exogenous ADM2 administration significantly restored cell migration via the Akt-CREB signaling pathway. In conclusion, RhoGDI2 and ADM2 play important roles in the migration of CRIF1-deficient endothelial cells., Competing Interests: The authors have declared that no competing interests exist.