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Heat shock proteins (HSPs) are a group of highly conserved proteins found in a wide range of organisms. In recent years, members of the HSP family were overexpressed in various tumors and widely involved in oncogenesis, tumor development, and therapeutic resistance. In our previous study, DNAJC24, a member of the DNAJ/HSP40 family of HSPs, was found to be closely associated with the malignant phenotype of hepatocellular carcinoma. However, its relationship with other malignancies needs to be further explored. Herein, we demonstrated that DNAJC24 exhibited upregulated expression in LUAD tissue samples and predicted poor survival in LUAD patients. The upregulation of DNAJC24 expression promoted proliferation and invasion of LUAD cells in A549 and NCI‐H1299 cell lines. Further studies revealed that DNAJC24 could regulate the PI3K/AKT signaling pathway by affecting AKT phosphorylation. In addition, a series of experiments such as Co‐IP and mass spectrometry confirmed that DNAJC24 could directly interact with PCNA and promoted the malignant phenotypic transformation of LUAD. In conclusion, our results suggested that DNAJC24 played an important role in the progression of LUAD and may serve as a specific prognostic biomarker for LUAD patients. The DNAJC24/PCNA/AKT axis may be a potential target for future individualized and precise treatment of LUAD patients. [ABSTRACT FROM AUTHOR]

Appropriate Ca2+ concentration in the endoplasmic reticulum (ER), modulating cytosolic Ca2+ signal, serves significant roles in physiological function of pancreatic β cells. To maintaining ER homeostasis, Ca2+ movement across the ER membrane is always accompanied by a simultaneous K+ flux in the opposite direction. KCNH6 was proven to modulate insulin secretion by controlling plasma membrane action potential duration and intracellular Ca2+ influx. Meanwhile, the specific function of KCNH6 in pancreatic β‐cells remains unclear. In this study, we found that KCNH6 exhibited mainly ER localization and Kcnh6 β‐cell‐specific knockout (βKO) mice suffered from abnormal glucose tolerance and impaired insulin secretion in adulthood. ER Ca2+ store was overloaded in islets of βKO mice, which contributed to ER stress and ER stress‐induced apoptosis in β cells. Next, we verified that ethanol treatment induced increases in ER Ca2+ store and apoptosis in pancreatic β cells, whereas adenovirus‐mediated KCNH6 overexpression in islets attenuated ethanol‐induced ER stress and apoptosis. In addition, tail‐vein injections of KCNH6 lentivirus rescued KCNH6 expression in βKO mice, restored ER Ca2+ overload and attenuated ER stress in β cells, which further confirms that KCNH6 protects islets from ER stress and apoptosis. These data suggest that KCNH6 on the ER membrane may help to stabilize intracellular ER Ca2+ stores and protect β cells from ER stress and apoptosis. In conclusion, our study reveals the protective potential of KCNH6‐targeting drugs in ER stress‐induced diabetes. [ABSTRACT FROM AUTHOR]

The adenopituitary secretes follicle‐stimulating hormone (FSH), which plays a crucial role in regulating the growth, development, and reproductive functions of organisms. Investigating the process of FSH synthesis and secretion can offer valuable insights into potential areas of focus for reproductive research. Epidermal growth factor (EGF) is a significant paracrine/autocrine factor within the body, and studies have demonstrated its ability to stimulate FSH secretion in animals. However, the precise mechanisms that regulate this action are still poorly understood. In this research, in vivo and in vitro experiments showed that the activation of epidermal growth factor receptor (EGFR) by EGF induces the upregulation of miR‐27b‐3p and that miR‐27b‐3p targets and inhibits Foxo1 mRNA expression, resulting in increased FSH synthesis and secretion. In summary, this study elucidates the precise molecular mechanism through which EGF governs the synthesis and secretion of FSH via the EGFR/miR‐27b‐3p/FOXO1 pathway. [ABSTRACT FROM AUTHOR]

Schizophrenia, affecting approximately 1% of the global population, is often treated with olanzapine. Despite its efficacy, olanzapine's prolonged use has been associated with an increased risk of cardiovascular diseases and nonalcoholic fatty liver disease (NAFLD); however, the underlying mechanism remains unclear. Proprotein convertase subtilisin kexin type 9 (PCSK9) plays a crucial role in lipid metabolism and is involved in NAFLD pathogenesis via an unknown mechanism. This study aims to investigate the role of PCSK9 in olanzapine‐induced NAFLD. C57BL/6J mice and HepG2 and AML12 cell lines were treated with varying concentrations of olanzapine to examine the effects of olanzapine on PCSK9 and lipid metabolism. PCSK9 levels were manipulated using recombinant proteins, plasmids, and small interfering RNAs in vitro, and the effects on hepatic lipid accumulation and gene expression related to lipid metabolism were assessed. Olanzapine treatment significantly increased PCSK9 levels in both animal and cell line models, correlating with elevated lipid accumulation. PCSK9 manipulation demonstrated its central role in mediating hepatic steatosis through both receptor‐dependent pathways (impacting NPC1L1) and receptor‐independent pathways (affecting lipid synthesis, uptake, and cholesterol biosynthesis). Interestingly, upregulation of SREBP‐1c, rather than SREBP‐2, was identified as a key driver of PCSK9 increase in olanzapine‐induced NAFLD. Our findings establish PCSK9 as a pivotal factor in olanzapine‐induced NAFLD, influencing both receptor‐related and metabolic pathways. This highlights PCSK9 inhibitors as potential therapeutic agents for managing NAFLD in schizophrenia patients treated with olanzapine. [ABSTRACT FROM AUTHOR]

Fibroblast activation disorder is one of the main pathogenic characteristics of diabetic wounds. Orchestrated fibroblast functions and myofibroblast differentiation are crucial for wound contracture and extracellular matrix (ECM) formation. Pyruvate dehydrogenase kinase 4 (PDK4), a key enzyme regulating energy metabolism, has been implicated in modulating fibroblast function, but its specific role in diabetic wounds remains poorly understood. In this study, we investigated the impact of PDK4 on diabetic wounds and its underlying mechanisms. To assess the effect of PDK4 on human dermal fibroblasts (HDFs), we conducted CCK‐8, EdU proliferation assay, wound healing assay, transwell assay, flow cytometry, and western blot analyses. Metabolic shifts were analyzed using the Seahorse XF analyzer, while changes in metabolite expression were measured through LC–MS. Local recombinant PDK4 administration was implemented to evaluate its influence on wound healing in diabetic mice. Finally, we found that sufficient PDK4 expression is essential for a normal wound‐healing process, while PDK4 is low expressed in diabetic wound tissues and fibroblasts. PDK4 promotes proliferation, migration, and myofibroblast differentiation of HDFs and accelerates wound healing in diabetic mice. Mechanistically, PDK4‐induced metabolic reprogramming increases the level of succinate that inhibits PHD2 enzyme activity, thus leading to the stability of the HIF‐1α protein, during which process the elevated HIF‐1α mRNA by PDK4 is also indispensable. In conclusion, PDK4 promotes fibroblast functions through regulation of HIF‐1α protein stability and gene expression. Local recombinant PDK4 administration accelerates wound healing in diabetic mice. [ABSTRACT FROM AUTHOR]

Many studies have shown that the actin cytoskeleton plays an essential role in the initiation and progression of cancer. As an actin‐binding protein, Twinfilin1 (TWF1) plays an important role in regulating cytoskeleton‐related functions. However, little is known about the expression and function of TWF1 in human tumors. The present study aimed to investigate the functional roles and the underlying molecular mechanisms of TWF1 in human lung adenocarcinoma (LUAD). By using bioinformatics databases and tumor tissues, TWF1 expression was found to be higher in LUAD tissues than in adjacent tissues and poor survival was predicted in patients with LUAD. In vitro and in vivo assays indicated that downregulation of TWF1 expression suppressed LUAD cells invasion and migration. Further studies revealed that TWF1 interacted with p62 and was involved in the regulation of autophagy. The molecular mechanisms underlying TWF1 were investigated by RNA‐seq analysis and a series of functional experiments. The results showed that downregulation of TWF1 suppressed LUAD progression through the cAMP signaling pathway. Therefore, overexpression of TWF1 in LUAD promoted migration, invasion, and autophagy through the cAMP signaling pathway. [ABSTRACT FROM AUTHOR]

Nectin‐like family members (Necls) are involved in synaptic organization. In contrast to that of Necl‐2/CADM1/SynCAM1, which is critical in synaptic events, investigation of Necl‐4/CADM4/SynCAM4 in synapses has largely lagged behind given the particularity of homophilic self‐interactions compared to interactions with other Necls. We sought to further understand the role of Necl‐4 in synapses and found that knockout of Necl‐4 led to aberrant expression levels of proteins mediating synaptic function in cortex homogenates and augmented accumulation of ionotropic glutamate receptor in postsynaptic density fractions, although a compensatory effect of Necl‐1 on the expression levels existed. Concurrently, we also found increased synaptic clefts in the cortex and simplified dendritic morphology of primary cultured cortical neurons. Experiments on individual behaviors suggested that compared to their wild‐type littermates, Necl‐4‐KO mice exhibited impaired acquisition of spatial memory and working memory and enhanced behavioral despair and anxiety‐like behavior. These findings suggest that Necl‐4 mediates synaptic function and related behaviors through an indispensable role and offer a new perspective about collaboration and specialization among Necls. [ABSTRACT FROM AUTHOR]

Ferroptosis is an iron‐dependent form of nonapoptotic cell death characterized by the accumulation of lipid peroxides in cells. In recent years, extensive attention has been dedicated to exploring safe and effective natural ferroptosis regulators which can provide novel treatment strategies for ferroptosis‐related diseases. This study identified galangin, a natural flavonoid, as an effective inhibitor of ferroptosis, which could increase cell viability in RSL3‐inhibited HT1080 cells, decrease levels of lipid ROS and MDA, improve PTGS2 mRNA expression, and enhance the expression of glutathione peroxidase 4 (GPX4). Ferroptosis is widely present in ischemia‐reperfusion (IR) injury. This study found that galangin significantly ameliorated the pathological damage of liver tissue in mice with IR, reduced levels of serum ALT, AST, and MDA, and increased the expression of GPX4. The results of RNA‐seq exhibited ferroptosis was significant and the PI3K/AKT pathway deserved to explore the inhibition effects of galangin on ferroptosis. Indeed, galangin treatment significantly rescued RSL3‐inhibited phosphorylation levels of PI3K, AKT, and CREB proteins, and the ferroptosis inhibitory effects of galangin were counteracted by PI3K inhibitor LY294002. These findings indicated that galangin may exert its anti‐ferroptosis effects via activating the PI3K/AKT/CREB signaling pathway and it will hopefully serve as a promising effective measure to attenuate IR injury by inhibiting ferroptosis. [ABSTRACT FROM AUTHOR]

Previous studies have found microRNA‐1 (miR‐1) and hyperpolarization‐activated cyclic nucleotide‐gated channel 2 (HCN2) may be involved in the pathogenesis of thyroid hormone (TH) induced cardiac hypertrophy. However, little is known about the role of miR‐1 and HCN2 in thyroid stimulation hormone (TSH)‐induced cardiac dysfunction. In order to investigate the molecular mechanisms of TSH induced cardiac dysfunction and the role of miR‐1/HCN2 in that process, we evaluated the expression of miR‐1a/HCN2 in the ventricular myocardium of hypothyroid mice and in TSH‐stimulated H9c2 cardiomyocytes. Our data revealed that hypothyroidism mice had smaller hearts, ventricular muscle atrophy, and cardiac contractile dysfunction compared with euthyroid controls. The upregulation of miR‐1a and downregulation of HCN2 were found in ventricular myocardium of hypothyroid mice and TSH‐stimulated H9c2 cardiomyocytes, indicating that miR‐1a and HCN2 may be involved in TSH‐induced cardiac dysfunction. We also found that the regulation of miR‐1a and HCN2 expression and HCN2 channel activity by TSH requires TSHR, while the regulation of HCN2 expression and HCN2 channel function by TSH requires miR‐1a. Thus, our data revealed the potential mechanism of TSH‐induced cardiac dysfunction and might shed new light on the pathological role of miR‐1a/HCN2 in hypothyroid heart disease. [ABSTRACT FROM AUTHOR]

Histone deacetylase 11 (HDAC11) is aberrantly expressed in many types of cancer, and such abnormalities are associated with tumor immunity and heterogeneous clinical outcomes. Here, we explore the prognostic value and immunological function of HDAC11 across 33 cancer types. We observe HDAC11 is aberrantly expressed in 25 cancer types and positively or negatively associated with prognosis in different cancers. HDAC11 played a protective prognostic role in KIRP, KIRC, LGG, PCPG, READ, and UVM, which was contrary to the conventional opinion that HDAC11 was an oncogenic gene. Moreover, HDAC11 is negatively associated with tumor immune components, most immune checkpoint genes, and key cytokine expression. HDAC11 is correlated with tumor mutational burden in 11 cancer types and with microsatellite instability in 9 cancer types, suggesting HDAC11 may affect a patient's response to immune checkpoint inhibitor (ICI) therapy. In addition, HDAC11 is negatively correlated with the drug sensitivity of oxaliplatin, carmustine, ifosfamide, imexon, lomustine, and BN‐2629, indicating the potential synergy between HDAC11 inhibitors and these anti‐tumor drugs. In vitro assays indicate that HDAC11 inhibitor SIS17 combined with oxaliplatin shows a synergistic cytotoxic role in K562 cells while SIS17 has an antagonistic effect on the cytotoxic role of oxaliplatin in 769P cells. HDAC11 is also associated with hallmark pathways, including epithelial mesenchymal transition, IL‑6/JAK/STAT3, and allograft rejection pathways. Overall, we provide clues regarding the key role of HDAC11 in multiple cancers. [ABSTRACT FROM AUTHOR]

Studies of neuroglial interaction largely depend on cell‐specific gene knockout (KO) experiments using Cre recombinase. However, genes known as glial‐specific genes have recently been reported to be expressed in neuroglial stem cells, leading to the possibility that a glia‐specific Cre driver results in unwanted gene deletion in neurons, which may affect sound interpretation. 2′,3′‐Cyclic nucleotide 3′‐phosphodiesterase (CNP) is generally considered to be an oligodendrocyte (OL) marker. Accordingly, Cnp promoter‐controlled Cre recombinase has been used to create OL‐specific gene targeting mice. However, in this study, using Rosa26‐tdTomato‐reporter/Cnp‐Cre mice, we found that many forebrain neurons and cerebellar Purkinje neurons belong to the lineages of Cnp‐expressing neuroglial stem cells. To answer whether gene targeting by Cnp‐Cre can induce neuron‐autonomous defects, we conditionally deleted an essential autophagy gene, Atg7, in Cnp‐Cre mice. The Cnp‐Cre‐mediated Atg7 KO mice showed extensive p62 inclusion in neurons, including cerebellar Purkinje neurons with extensive neurodegeneration. Furthermore, neuronal areas showing p62 inclusion in Cnp‐Cre‐mediated Atg7 KO mice overlapped with the neuronal lineage of Cnp‐expressing neuroglial stem cells. Moreover, Cnp‐Cre‐mediated Atg7‐KO mice did not develop critical defects in myelination. Our results demonstrate that a large population of central neurons are derived from Cnp‐expressing neuroglial stem cells; thus, conditional gene targeting using the Cnp promoter, which is known to be OL‐specific, can induce neuron‐autonomous phenotypes. [ABSTRACT FROM AUTHOR]

Mammalian LGR5 and LGR4, markers of adult stem cells, are involved in many physiological functions by enhancing WNT signaling. However, whether LGR5 and LGR4 are coupled to other intracellular signaling pathways to regulate stem cell function remains unknown. Here, we show that LGR5 and LGR4 can constitutively activate NF‐κB signaling in a ligand‐independent manner, which is dependent on their C‐termini, but independent of receptor endocytosis. Moreover, the C‐termini of LGR5/4 interact with TROY, which is required for activating NF‐κB signaling. In small intestinal crypt organoids, overexpression of a C‐terminal deletion mutant of LGR5 inhibits the growth and bud formation of organoids, whereas overexpression of the R‐spondin‐binding mutant of LGR5 that is defective for WNT signaling can still promote organoid growth. Our study reveals that NF‐κB signaling, regulated by LGR5 and LGR4, plays an important role in the survival of colon cancer cells and the growth of intestinal crypts. Our findings also suggest that LGR5/4‐induced NF‐κB signaling and WNT signaling may co‐regulate the growth of LGR5+ adult stem cells and intestinal crypts. [ABSTRACT FROM AUTHOR]

The COP9 signalosome (CSN) is a conserved eukaryotic complex, essential for vitality in all multicellular organisms and critical for the turnover of key cellular proteins through catalytic and non‐catalytic activities. Saccharomyces cerevisiae is a powerful model organism for studying fundamental aspects of the CSN complex, since it includes a conserved enzymatic core but lacks non‐catalytic activities, probably explaining its non‐essentiality for life. A previous transcriptomic analysis of an S. cerevisiae strain deleted in the CSN5/RRI1 gene, encoding to the CSN catalytic subunit, revealed a downregulation of genes involved in lipid metabolism. We now show that the S. cerevisiae CSN holocomplex is essential for cellular lipid homeostasis. Defects in CSN assembly or activity lead to decreased quantities of ergosterol and unsaturated fatty acids (UFA); vacuole defects; diminished lipid droplets (LDs) size; and to accumulation of endoplasmic reticulum (ER) stress. The molecular mechanism behind these findings depends on CSN involvement in upregulating mRNA expression of SPT23. Spt23 is a novel activator of lipid desaturation and ergosterol biosynthesis. Our data reveal for the first time a functional link between the CSN holocomplex and Spt23. Moreover, CSN‐dependent upregulation of SPT23 transcription is necessary for the fine‐tuning of lipid homeostasis and for cellular health. [ABSTRACT FROM AUTHOR]

Nutritional status during intrauterine and/or early postnatal life has substantial influence on adult offspring health. Along these lines, there is a growing body of evidence illustrating that high fat diet (HFD)‐induced maternal obesity can regulate fetal bone development. Thus, we investigated the effects of maternal obesity on both fetal skeletal development and mechanisms linking maternal obesity to osteoblast differentiation in offspring. Embryonic osteogenic calvarial cells (EOCCs) were isolated from fetuses at gestational day 18.5 (E18.5) of HFD‐induced obese rat dams. We observed impaired differentiation of EOCCs to mature osteoblasts from HFD obese dams. ChIP‐seq‐based genome‐wide localization of the repressive histone mark H3K27me3 (mediated via the polycomb histone methyltransferase, enhancer of zeste homologue 2 [Ezh2]) showed that this phenotype was associated with increased enrichment of H3K27me3 on the gene of SATB2, a critical transcription factor required for osteoblast differentiation. Knockdown of Ezh2 in EOCCs and ST2 cells increased SATB2 expression; while Ezh2 overexpression in EOCCs and ST2 cells decreased SATB2 expression. These data were consistent with experimental results showing strong association between H3K27me3, Ezh2, and SATB2 in cells from rats and humans. We have further presented that SATB2 mRNA and protein expression were increased in bones, and increased trabecular bone mass from pre‐osteoblast specific Ezh2 deletion (Ezh2flox/flox Osx‐Cre+ cko) mice compared with those from control Cre+ mice. These findings indicate that maternal HFD‐induced obesity may be associated with decreasing fetal pre‐osteoblastic cell differentiation, under epigenetic control of SATB2 expression via Ezh2‐dependent mechanisms. [ABSTRACT FROM AUTHOR]

The receptor for advanced glycan end products (RAGE) has been identified as a susceptibility gene for chronic obstructive pulmonary disease (COPD) in genome-wide association studies (GWASs). However, less is known about how RAGE is involved in the pathogenesis of COPD. To determine the molecular mechanism by which RAGE influences COPD in experimental COPD models, we investigated the efficacy of the RAGE-specific antagonist FPS-ZM1 administration in in vivo and in vitro COPD models. We injected elastase intratracheally and the RAGE antagonist FPS-ZM1 in mice, and the infiltrated inflammatory cells and cytokines were assessed by ELISA. Cellular expression of RAGE was determined in protein, serum, and bronchoalveolar lavage fluid of mice and lungs and serum of human donors and patients with COPD. Downstream damage-associated molecular pattern (DAMP) pathway activation in vivo and in vitro and in patients with COPD was assessed by immunofluorescence staining, Western blot analysis, and ELISA. The expression of membrane RAGE in initiating the inflammatory response and of soluble RAGE acting as a decoy were associated with up-regulation of the DAMP-related signaling pathway via Nrf2. FPS-ZM1 administration significantly reversed emphysema in the lung of mice. Moreover, FPS-ZM1 treatment significantly reduced lung inflammation in Nrf2+/+, but not in Nrf2-/- mice. Thus, our data indicate for the first time that RAGE inhibition has an essential protective role in COPD. Our observation of RAGE inhibition provided novel insight into its potential as a therapeutic target in emphysema/COPD.--Lee, H., Park, J.-R., Kim, W. J., Sundar, I. K., Rahman, I., Park, S.-M., Yang. S.-R. Blockade of RAGE ameliorates elastase-induced emphysema development and progression via RAGE-DAMP signaling. [ABSTRACT FROM AUTHOR]

Tribbles 3 (TRB3) is a pseudokinase that has been found in multiple tissues in response to various stress stimuli, such as nutrient deprivation and endoplasmic reticulum (ER) stress. We recently found that TRB3 has the potential to regulate skeletal muscle mass at the basal state. However, it has not yet been explored whether TRB3 regulates skeletal muscle mass under atrophic conditions. Here, we report that food deprivation for 48 h in mice significantly reduces muscle mass by ~15% and increases TRB3 expression, which is associated with increased ER stress. Interestingly, inhibition of ER stress in C2C12 myotubes reduces food deprivation-induced expression of TRB3 and muscle-specific E3-ubiquitin ligases. In further in vivo experiments, muscle-specific TRB3 transgenic mice increase food deprivation-induced muscle atrophy compared with wild-type (WT) littermates presumably by the increased proteolysis. On the other hand, TRB3 knockout mice ameliorate food deprivation-induced atrophy compared with WT littermates by preserving a higher protein synthesis rate. These results indicate that TRB3 plays a pivotal role in skeletal muscle mass regulation under food deprivation-induced muscle atrophy and TRB3 could be a pharmaceutical target to prevent skeletal muscle atrophy. [ABSTRACT FROM AUTHOR]

Staphylococcal nuclease domain-containing protein 1 (SND1) has been reported as an oncoprotein in a variety of cancers involving multiple processes, including proliferation, angiogenesis, and metastasis. However, the mechanisms underlying metastasis remain largely unknown. Herein, by using the ovarian cancer cell line SKOV3, which has high metastasis ability, we showed that loss-of-function of SND1 dramatically suppressed the invasion and migration of SKOV3 cells. We then performed gene expression profiles and further verified (by use of quantitative PCR and Western blot analysis) that loss-of-function of SND1 resulted in up-regulation of epithelial markers, such as epithelial cadherin and claudin 1, and down-regulation of mesenchymal markers, including neural cadherin and vimentin. Moreover, we illustrated that SLUG, a key transcription factor implicated in epithelial-mesenchymal transition and metastasis, acts as an essential effector of the SND1-promoted epithelial-mesenchymal transition process via regulating N-CAD and VIM expression (or E-CAD and CLDN1). The underlying molecular mechanisms illustrated that SND1 regulates the gene transcriptional activation of SLUG by increasing chromatin accessibility through the recruitment of the acetyltransferases GCN5 and CBP/p300 to the SLUG promoter proximal region. Overall, SND1 was identified as a novel upstream regulator of SLUG, which plays important roles in regulating the E-CAD/N-CAD expression switch. [ABSTRACT FROM AUTHOR]

Endothelial progenitor cells (EPCs) contribute to neovascularization in tumors. However, the relationship of EPCs and tumor-induced angiogenesis still remains to be clarified. The present study aimed at investigating the influence of 4 different tumor types on angiogenic properties of EPCs in an in vitro and in vivo rat model. It could be demonstrated that in vitro proliferation, migration, and angiogenic abilities and genetic modifications of EPCs are controlled in a tumor-type-dependent manner. The proangiogenic effect of mammary carcinoma, osteosarcoma, and rhabdomyosarcoma cells was more pronounced compared to colon carcinoma cells. Coinjection of encapsulated tumor cells, especially mammary carcinoma cells, and EPCs in a rat model confirmed a contributing effect of EPCs in tumor vascularization. Cytokines secreted by tumors such as monocyte chemoattractant protein 1, macrophage inflammatory protein 2, and TNF-related apoptosis-inducing ligand play a pivotal role in the tumor cell-EPC interaction, leading to enhanced migration and angiogenesis. With the present study, we were able to decipher possible underlying mechanisms by which EPCs are stimulated by tumor cells and contribute to tumor vascularization. The present study will contribute to a better understanding of tumor-induced vascularization, thus facilitating the development of therapeutic strategies targeting tumor-EPC interactions. [ABSTRACT FROM AUTHOR]

The actin cytoskeleton is composed of a highly dynamic network of filamentous proteins, yet the molecular mechanism that regulates its organization and remodeling remains elusive. In this study, Na+/H+ exchanger regulatory factor (NHERF)-1 loss-of-function and gain-of-function experiments reveal that polymerized actin cytoskeleton (F-actin) in HeLa cells is disorganized by NHERF1, whereas actin protein expression levels exhibit no detectable change. To elucidate the molecular mechanism underlying actin cytoskeleton disorganization by NHERF1, a combined 2-dimensional electrophoresis-matrix-assisted laser desorption/ionization-time of flight mass spectrometry approach was used to screen for proteins regulated by NHERF1 in HeLa cells. α-Actinin-4, an actin cross-linking protein, was identified. Glutathione S-transferase pull-down and coimmunoprecipitation studies showed the α-actinin-4 carboxyl-terminal region specifically interacted with the NHERF1 postsynaptic density 95/disc-large/zona occludens-1 domain. The NHERF1/α-actinin-4 interaction increased α-actinin-4 ubiquitination and decreased its expression levels, resulting in actin cytoskeleton disassembly. Our study identified α-actinin-4 as a novel NHERF1 interaction partner and provided new insights into the regulatory mechanism of the actin cytoskeleton by NHERF1. [ABSTRACT FROM AUTHOR]

VEGF-induced neovascularization plays a pivotal role in corneal neovascularization (CoNV). The current study investigated the potential effect of ginsenoside Rh2 (GRh2) on neovascularization. In HUVECs, pretreatment with GRh2 largely attenuated VEGF-induced cell proliferation, migration, and vessel-like tube formation in vitro. At the molecular level, GRh2 disrupted VEGF-induced VEGF receptor 2 (VEGFR2)-Grb-2-associated binder 1 (Gab1) association in HUVECs, causing inactivation of downstream AKT and ERK signaling. Gab1 knockdown (by targeted short hairpin RNA) similarly inhibited HUVEC proliferation and migration. Notably, GRh2 was ineffective against VEGF in Gab1-silenced HUVECs. In a mouse cornea alkali burn model, GRh2 eyedrops inhibited alkali-induced neovascularization and inflammatory cell infiltrations in the cornea. Furthermore, alkali-induced corneal expression of mRNAs/long noncoding RNAs in cornea were largely attenuated by GRh2. Overall, GRh2 inhibits VEGF-induced angiogenic effect via inhibiting VEGFR2-Gab1 signaling in vitro. It also alleviates angiogenic and inflammatory responses in alkali burn-treated mouse corneas.--Zhang, X.-P., Li, K.-R., Yu, Q., Yao, M.-D., Ge, H.-M., Li, X.-M., Jiang, Q., Yao, J., Cao, C. Ginsenoside Rh2 inhibits vascular endothelial growth factor-induced corneal neovascularization. [ABSTRACT FROM AUTHOR]

Exposure to microgravity results in cardiovascular deconditioning, and cerebrovascular oxidative stress injury has been suggested to occur. To elucidate the mechanism for this condition, we investigated whether simulated microgravity induces mitochondrial dysfunction in rat arteries. Four-week hindlimb unweighting (HU) was used to simulate microgravity in rats. Mitochondrial reactive oxygen species (ROS), mitochondrial membrane potential (Δωm), mitochondrial permeability transition pore (mPTP) opening, mitochondrial respiratory control ratio (RCR), MnSOD/GPx activity and expression, and mitochondrial malondialdehyde (MDA) were examined in rat cerebral and mesenteric VSMCs. Compared with the control rats, mitochondrial ROS levels, mPTP opening, and MDA content increased significantly (P< 0.001, P<0.01, and P<0.01, respectively), Δωm, RCR, MnSOD/GPx activity (P<0.001 for Δωm and RCR; P<0.05 for MnSOD; and P< 0.001 for GPx activity) and protein abundance of mitochondrial MnSOD/GPx-1 decreased (P< 0.001 for MnSOD and GPx-1) in HU rat cerebral but not mesenteric arteries. Chronic treatment with NADPH oxidase inhibitor apocynin and mitochondria-targeted antioxidant mitoTempol promoted recovery of mitochondrial function in HU rat cerebral arteries, but exerted no effects on HU rat mesenteric arteries. Therefore, simulated microgravity resulted in cerebrovascular mitochondrial dysfunction, and crosstalk between NADPH oxidase and mitochondria participated in the process. [ABSTRACT FROM AUTHOR]