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The highly regulated proliferation of adipocytes plays a momentous role in fat development and obesity. Hoxa5 is an important member of the Hox family, its encoded protein is an important transcription factor related to development, and its differential expression in different adipose tissues seems to indicate that Hoxa5 may be involved in the regulation of adipocyte proliferation. To evaluate the regulatory mechanism of Hoxa5 on adipocyte proliferation, we constructed a variety of Hoxa5 expression vectors in vivo and in vitro to explore its mechanism on adipocyte proliferation and its potential impact on obesity. We observed that the overexpression of Hoxa5 strongly reduces cell counts and Hoxa5 can inhibit cell proliferation and block cell cycle progression by regulating the expression of genes such as Cyclin E, Cyclin D1, and p53. Most importantly, we demonstrated that Hoxa5 exerts its effect by regulating the signaling pathway of Janus kinase 2 (JAK2) signal transduction and transcription 3 (STAT3) activator, as well as binding to the promoter region of Ccne1 and inhibiting the transcription of Ccne1. This study provides an in-depth understanding of the potential molecular mechanism of Hoxa5 inhibiting adipocyte proliferation. Our results suggest the importance of Hoxa5 in the treatment of obesity. [ABSTRACT FROM AUTHOR]

Hydrogen polysulfides (H2Sn, n > 1), as the oxidized forms of H2S, have attracted increasing attention these years due to their involvement in signaling transduction and cytoprotective processes. It is necessary to detect H2Sn in living systems for the study of their functions. In this work, we report a BODIPY-based near-infrared emitting fluorescence probe NIR-PHS1, with "turn-on" response, rapid response rate (within 10 min), outstanding selectivity and excellent sensitivity (detection limit = 12 nM) response towards H2Sn. The probe was successfully applied to the visualizing of endogenous H2Sn in living cells. Moreover, it can be used for near-infrared in vivo imaging of H2Sn in living mice. Therefore, NIR-PHS1 could be a potential imaging tool to study the biological roles of H2Sn in living systems. [ABSTRACT FROM AUTHOR]

Apigetrin (APG), as a flavonoid, has many cellular bioactivities, including regulation of oxidative stress, and induction of apoptosis. However, the means by which APG suppresses human gastric cancer are still little to be understood. In the present study, the anti-cancer effects of APG on human gastric cancer cells were investigated. The results indicated that APG could suppress the proliferation and induce apoptosis in gastric cancer cells. Its role in apoptosis induction was through reducing Bcl-2, and enhancing Bax, Caspase-9/-3 and poly ADP-ribose polymerase (PARP) cleavage. In addition, APG incubation resulted in the generation of intracellular reactive oxygen species (ROS) in cells. Meanwhile, APG suppressed constitutive and interleukin-6 (IL-6)-stimulated signal transducer and activator of transcription 3 (STAT3), Janus kinase 2 gene (JAK2) and Src activation. However, ROS scavenger, N-acety-l-cysteine (NAC), diminished apoptosis induced by APG. And APG-triggered de-phosphorylation of STAT3/JAK2 was rescued by NAC pre-treatment. In vivo , APG administration significantly inhibited the gastric cancer cell xenograft tumorigenesis through inducing apoptosis and inhibiting STAT3/JAK2 pathways. Taken together, the findings above illustrated that APG might be used as a promising candidate against human gastric cancer progression. [ABSTRACT FROM AUTHOR]

Background Peroxisome proliferator-activated receptor gamma ( PPAR γ) signaling has been shown to regulate lipogenesis and lipid accumulation. Previous studies have shown that hepatic PPAR γ is up-regulated in steatotic liver of both animal and human. However, the effects of hepatic PPAR γ signaling on alcoholic liver disease ( ALD) remain elusive. Methods To determine the role of hepatic PPAR γ signaling on ALD, wild-type ( WT) and hepatocyte-specific PPAR γ knockdown ( PPAR γ∆ Hep) mice were fed a modified Lieber- De Carli alcohol or isocaloric maltose dextrin control liquid diet for 8 weeks to induce ALD. Blood parameters, hepatic steatosis, and inflammation were measured after 8-week alcohol feeding. Results Alcohol feeding to WT mice resulted in liver damage (alanine aminotransferase [ ALT], 94.68 ± 17.05 U/L; aspartate aminotransferase [ AST], 55.87 ± 11.29 U/L), which was significantly alleviated by hepatic PPAR γ knockdown ( ALT, 57.36 ± 14.98 U/L; AST, 38.06 ± 3.35 U/L). Alcohol feeding led to marked lipid accumulation and up-regulation of lipogenic genes including fatty acid transport protein 1 ( FATP1), acetyl- Co A carboxylase ( ACC), fatty acid synthase ( FASN), lipin1 (LIPIN1), diacylglycerol acyltransferase 1 ( DGAT1), and diacylglycerol acyltransferase 2 ( DGAT2) in the livers of WT mice. Knockdown of hepatic PPAR γ significantly alleviated alcohol-induced lipid accumulation and abolished the up-regulation of FASN, DGAT1, and DGAT2. Silencing of PPAR γ in FL83 B cells significantly decreased ethanol ( Et OH)-, linoleic acid-, and Et OH plus linoleic acid-induced lipid accumulation. Knockdown of hepatic PPAR γ also significantly reduced alcohol-induced inflammatory chemokine (monocyte chemotactic protein 1 [ MCP1], keratinocyte-derived chemokine [ KC], interferon gamma-induced protein 10 [ IP-10]) and inflammatory infiltration (lymphocyte antigen 6 complex, locus G [ Ly6 G], and F4/80). Conclusions The results suggest that hepatic PPAR γ signaling contributes to alcohol-induced liver injury by promoting hepatic steatosis and inflammation. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, we investigated the mechanism of C-type natriuretic peptide (CNP)-induced inhibitory effect on spontaneous contraction of gastric antral smooth muscle to clarify CNP-NPR-B/pGC-cGMP downstream signal transduction pathway using organ bath and ELISA methods in rat. CNP significantly reduced the amplitude of the spontaneous contraction and increased the contents of cGMP and cAMP in the gastric antral smooth muscle tissue. In the presence of IBMX, a non-selective phosphodiesterase (PDE) inhibitor, the inhibitory effect of CNP on spontaneous contraction was significantly suppressed; however, the production of cGMP but not cAMP was still increased by CNP. EHNA, a PDE2 inhibitor, did not affect both CNP-induced inhibition of the contraction and CNP-induced increase of cGMP and cAMP generations in gastric smooth muscle tissue, while milrinone, a PDE3 inhibitor, similar to IBMX, attenuated the CNP-induced inhibitory effect on spontaneous contraction and increased the content of cGMP but not cAMP. The results suggest that cGMP–PDE3–cAMP signal pathway is also involved in the CNP-induced inhibition of gastric motility in rat. [Copyright &y& Elsevier]

Glioblastoma is a highly lethal adult brain tumor with no effective treatments. In this review, we discuss the potential to target cholesterol metabolism as a new strategy for treating glioblastomas. Twenty percent of cholesterol in the body is in the brain, yet the brain is unique among organs in that it has no access to dietary cholesterol and must synthesize it de novo. This suggests that therapies targeting cholesterol synthesis in brain tumors might render their effects without compromising cell viability in other organs. We will describe cholesterol synthesis and homeostatic feedback pathways in normal brain and brain tumors, as well as various strategies for targeting these pathways for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Pro-inflammatory cytokines play a vital role in the pathogenesis of alcoholic steatohepatitis. The present study was to determine the role of alcohol-induced oxidative stress in modulating cytokine production. A rat model of alcohol consumption was used to determine alcohol-induced hepatic cytokine expression. Chronic alcohol exposure caused lipid accumulation, oxidative stress, and inflammation in the livers of Wistar rats. The role of oxidative stress in regulating cell type-specific cytokine production was further dissected in vitro . Lipopolysaccharide (LPS) dose-dependently upregulated TNF-α, MIP-1α, MCP-1, and CINC-1 in Kupffer cells-SV40, whereas TNF-α dose-dependently induced CINC-1, IP-10, and MIP-2 expression in H4IIEC3 hepatoma cells. An additive effect on cytokine production was observed in both Kupffer cells-SV40 and hepatocytes when combined hydrogen peroxide with LPS or TNF-α, respectively, which was associated with NF-κB activation and histone H3 hyper-acetylation. Unexpectedly, an inhibitory effect of 4-hydroxynonenal on cytokine production was revealed in LPS-treated Kupffer cells-SV40. Mechanistic study showed that 4-hydroxynonenal significantly enhanced mRNA degradation of TNF-α, MCP-1, and MIP-1α, and decreased the protein levels of MCP-1 in LPS-stimulated Kupffer cells-SV40 through reducing the phosphorylation of mRNA binding proteins. This study suggests that Kupffer cells and hepatocytes express distinct pro-inflammatory cytokines/chemokines in response to alcohol intoxication, and oxidative products (4-hydroxynonenal) differentially modulate pro-inflammatory cytokine/chemokine production via NF-κB signaling, histone acetylation, and mRNA stability. [ABSTRACT FROM AUTHOR]

As in many other cancers, highly malignant proliferation and disordered cell division play irreplaceable roles in the exceedingly easy recurrence and complex progression of glioblastoma multiforme (GBM); however, mechanistic studies of the numerous regulators involved in this process are still insufficiently thorough. The role of BCAS3 has been studied in other cancers, but its role in GBM is unclear. Here, our goal was to investigate the expression pattern of BCAS3 in GBM and its potential mechanism of action. Using TCGA database and human GBM samples, we found that BCAS3 expression was up-regulated in GBM, and its high expression predicted poor prognosis. To further investigate the relationship between BCAS3 and GBM characteristics, we up-regulated and down-regulated BCAS3 expression in GBM to detect its effect on cell proliferation and cell cycle. At the same time, we established U87 cells stably overexpressing BCAS3 and generated an intracranial xenograft model to investigate the Potential role of BCAS3 in vivo. Finally, based on in vitro cell experiments and in vivo GBM xenograft models, we observed that BCAS3 significantly regulates GBM cell proliferation and cell cycle and that this regulation is associated with p53/GADD45α Signaling pathway. Taken together, our findings suggest that BCAS3 is inextricably linked to the progression of GBM and that targeting BCAS3 may have therapeutic effects in GBM patients. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Icariin restored LPS-induced lung inflammation and mitochondrial apoptosis. • Icariin improved immune inflammation through the complement C5a-C5aR1 axis. • Icariin alleviated lung injury by regulating TLR4 signaling pathways. Acute lung injury (ALI) is an acute respiratory-related progressive disorder, which lacks specific pharmacotherapy. Icariin (ICA) has been shown to be effective in treating ALI. However, the targets and pharmacological mechanisms underlying the effects of ICA in the treatment of ALI are relatively lacking. Based on network pharmacology and molecular docking analyses, the gene functions and potential target pathways of ICA in the treatment of ALI were determined. In addition, the underlying mechanisms of ICA were verified by immunohistochemistry, immunofluorescence, quantitative Real-time PCR, and Western blot in LPS-induced ALI mice. The biological processes targeted by ICA in the treatment of ALI included the pathological changes, inflammatory response, and cell signal transduction. Network pharmacology, molecular docking, and in vivo experimental results revealed that ICA inhibited the complement C5a-C5aR1 axis, TLR4 mediated NF-κB, MAPK, and JAK2-STAT3 signaling pathways related gene and protein expressions, and decreased inflammatory cytokine, chemokine, adhesion molecule expressions, and mitochondrial apoptosis in LPS-induced ALI. [ABSTRACT FROM AUTHOR]

Metastatic melanoma is a leading cause of death from skin diseases, and is often associated with activation of Wnt/β-catenin signaling pathway. We have examined the inhibitory effect of silymarin, a plant flavanoid from Silybum marianum, on cell migration of metastasis-specific human melanoma cell lines (A375 and Hs294t) and assessed whether Wnt/β-catenin signaling is the target of silymarin. Using an in vitro invasion assay, we found that treatment of human melanoma cell lines with silymarin resulted in concentration-dependent inhibition of cell migration, which was associated with accumulation of cytosolic β-catenin, while reducing the nuclear accumulation of β-catenin (i.e., β-catenin inactivation) and reducing the levels of matrix metalloproteinase (MMP) -2 and MMP-9 which are the down-stream targets of β-catenin. Silymarin enhanced: (i) the levels of casein kinase 1α, glycogen synthase kinase-3β and phosphorylated-β-catenin on critical residues Ser45, Ser33/37 and Thr41, and (ii) the binding of β-transducin repeat-containing proteins (β-TrCP) with phospho forms of bcatenin in melanoma cells. These events play important roles in degradation or inactivation of β-catenin. To verify whether β-catenin is a potent molecular target of silymarin, the effect of silymarin was determined on β-catenin-activated (Mel 1241) and β-catenin-inactivated (Mel 1011) melanoma cells. Treatment of Mel 1241 cells with silymarin or FH535, an inhibitor of Wnt/β-catenin pathway, significantly inhibited cell migration of Mel 1241 cells, which was associated with the elevated levels of casein kinase 1α and glycogen synthase kinase-3β, and decreased accumulation of nuclear β-catenin and inhibition of MMP-2 and MMP-9 levels. However, this effect of silymarin and FH535 was not found in Mel 1011 melanoma cells. These results indicate for the first time that silymarin inhibits melanoma cell migration by targeting β-catenin signaling pathway. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor alpha-induced protein 8-like 3 (TIPE3) is closely related to tumourigenesis and development. However, its role in human glioblastoma (GBM) and the underlying mechanisms remain unclear. In this study, we demonstrate that TIPE3 is upregulated in GBM, and its high expression predicts poor prognosis. TIPE3 depletion induces GBM cell apoptosis both in vitro and in vivo. Mechanism studies reveal that TIPE3 inhibits p38 phosphorylation and negatively regulates the p38 MAPK pathway. TIPE3 associates with p38. The nuclear translocation of p38 is blocked by TIPE3 overexpression. And p38 phosphorylation could regulate TIPE3-mediated p38 nuclear-cytopalsmic translocation but does not affect TIPE3-p38 association. Rescue experiments confirm that TIPE3 inhibits GBM cell apoptosis via the p38 MAPK pathway. In conclusion, TIPE3 inhibits p38 phosphorylation and blocks p38 nuclear translocation. This action thus negatively regulates the p38 MAPK pathway and results in GBM cell survival. [ABSTRACT FROM AUTHOR]

Abstract Thulium laser resection of the prostate (TmLRP), a major treatment for benign prostatic hyperplasia (BPH), has several postoperative complications that affect the patients' quality of life. The aim of this study was to investigate the effect of the M1 macrophage-secreted reactive oxygen species (ROS) on prostatic wound healing, and the role of MAPK signaling in this process. A co-culture model in vitro was established using macrophages and prostate epithelial or stromal cells. Cell proliferation, migration, apoptosis, MAPK pathway-related gene expression levels were evaluated by standard assays. In addition, an in vivo model of prostatectomy was established in beagles by subjecting them to TmLRP, and were either treated with N -acetyl-L-cysteine (NAC) and or placebo. Wound healing and re-epithelialization were analyzed histopathologically in both groups, in addition to macrophage polarization, oxidative stress levels and MAPK pathway-related proteins expressions. Intracellular ROS levels were significantly increased in the prostate epithelial and stromal cells following co-culture with M1-like macrophages and H 2 O 2 exposure via MAPK activation, which affected their proliferation, migration and apoptosis, and delayed the wound healing process. The cellular functions and wound healing capacity of the prostate cells were restored by blocking or clearing the macrophage-secreted ROS. In the beagle model, increased ROS levels impaired cellular functions, and appropriate removing ROS accelerated the wound healing process. Highlights • ROS hindered the healing of prostatic wound caused by prostatectomy. • ROS impacted proliferation and migration of prostate epithelial and stromal cells. • ROS affected the prostatic wound healing via MAPKs signaling pathways. • ROS scavengers could decrease the ROS level and accelerate wound healing. [ABSTRACT FROM AUTHOR]

Background: The glymphatic pathway transports cerebrospinal fluid through the brain, thereby facilitating waste removal. A unique aspect of this pathway is that its function depends on the state of consciousness of the brain and is associated with norepinephrine activity. A current view is that all anesthetics will increase glymphatic transport by inducing unconsciousness. This view implies that the effect of anesthetics on glymphatic transport should be independent of their mechanism of action, as long as they induce unconsciousness. We tested this hypothesis by comparing the supplementary effect of dexmedetomidine, which lowers norepinephrine, with isoflurane only, which does not.Methods: Female rats were anesthetized with either isoflurane (N = 8) or dexmedetomidine plus low-dose isoflurane (N = 8). Physiologic parameters were recorded continuously. Glymphatic transport was quantified by contrast-enhanced magnetic resonance imaging. Cerebrospinal fluid and gray and white matter volumes were quantified from T1 maps, and blood vessel diameters were extracted from time-of-flight magnetic resonance angiograms. Electroencephalograms were recorded in separate groups of rats.Results: Glymphatic transport was enhanced by 32% in rats anesthetized with dexmedetomidine plus low-dose isoflurane when compared with isoflurane. In the hippocampus, glymphatic clearance was sixfold more efficient during dexmedetomidine plus low-dose isoflurane anesthesia when compared with isoflurane. The respiratory and blood gas status was comparable in rats anesthetized with the two different anesthesia regimens. In the dexmedetomidine plus low-dose isoflurane rats, spindle oscillations (9 to 15 Hz) could be observed but not in isoflurane anesthetized rats.Conclusions: We propose that anesthetics affect the glymphatic pathway transport not simply by inducing unconsciousness but also by additional mechanisms, one of which is the repression of norepinephrine release. [ABSTRACT FROM AUTHOR]

Diabetic cardiomyopathy represents severe heart complications, and is the leading cause of morbidity and mortality among patients with diabetes. Although a few microRNAs (miRNAs) have been implicated in diabetes-related complications, a functional association between miRNAs and cardiac dysfunction in diabetic cardiomyopathy remains to be demonstrated. Our results show that miR-483-3p is upregulated in streptozotocin-induced diabetic mice, and cultured cardiomyocytes mimicking hyperglycemia. Overexpressing miR-483-3p in transgenic mice with diabetes mellitus (DM) exacerbated cardiomyocyte apoptosis by transcriptionally repressing insulin growth factor 1 (IGF1). Therefore, we have uncovered a novel signaling pathway, involving miR-483-3p-IGF1, that promotes myocardial cell apoptosis under high blood-glucose condition. Further, our study indicates that miR-483-3p could be a potential therapeutic target for managing diabetes-associated heart complications. [ABSTRACT FROM AUTHOR]

G-protein-coupled receptors (GPCRs) are key players in cell signaling, and their cell surface expression is tightly regulated. For many GPCRs such as ß2-AR (ß2-adrenergic receptor), receptor activation leads to downregulation of receptor surface expression, a phenomenon that has been extensively characterized. By contrast, some other GPCRs, such as GABAB receptor, remain relatively stable at the cell surface even after prolonged agonist treatment; however, the underlying mechanisms are unclear. Here, we identify the small GTPase Rap1 as a key regulator for promoting GABAB receptor surface expression. Agonist stimulation of GABAB receptor signals through Gai/o to inhibit Rap1GAPII (also known as Rap1GAP1b, an isoform of Rap1GAP1), thereby activating Rap1 (which has two isoforms, Rap1a and Rap1b) in cultured cerebellar granule neurons (CGNs). The active form of Rap1 is then recruited to GABAB receptor through physical interactions in CGNs. This Rap1-dependent signaling cascade promotes GABAB receptor surface expression by stimulating receptor recycling. Our results uncover a new mechanism regulating GPCR surface expression and also provide a potential explanation for the slow, long-lasting inhibitory action of GABA neurotransmitter. [ABSTRACT FROM AUTHOR]

Abstract: To facilitate the study of the CaMKIIα function in vivo, a CaMKIIα-GFP transgenic mouse line was generated. Here, our goal is to provide the first neuroanatomical characterization of GFP expression in the CNS of this line of mouse. Overall, CaMKIIα-GFP expression is strong and highly heterogeneous, with the dentate gyrus of the hippocampus as the most abundantly expressed region. In the hippocampus, around 70% of granule and pyramidal neurons expressed strong GFP. In the neocortex, presumed pyramidal neurons were GFP positive: around 32% of layer II/III and 35% of layer VI neurons expressed GFP, and a lower expression rate was found in other layers. In the thalamus and hypothalamus, strong GFP signals were detected in the neuropil. GFP-positive cells were also found in many other regions such as the spinal trigeminal nucleus, cerebellum and basal ganglia. We further compared the GFP expression with specific antibody staining for CaMKIIα and GABA. We found that GFP+ neurons were mostly positive for CaMKIIα-IR throughout the brain, with some exceptions throughout the brain, especially in the deeper layers of neocortex. GFP and GABA-IR marked distinct neuronal populations in most brain regions with the exception of granule cells in the olfactory bulb, purkinje cells in the cerebellar, and some layer I cells in neocortex. In conclusion, GFP expression in the CaMKIIα-GFP mice is similar to the endogenous expression of CaMKIIα protein, thus these mice can be used in in vivo and in vitro physiological studies in which visualization of CaMKIIα- neuronal populations is required. [Copyright &y& Elsevier]

Abstract: Hepatitis B virus X protein (HBx) is a multifunctional oncoprotein which plays a crucial role in the pathogenesis of hepatocellular carcinoma (HCC). However, the exact mechanisms remain controversial. Here we show that HBx strongly stimulated cell growth, promoted cell cycle progression and inhibited apoptosis of human non-tumor hepatic cell line L02 cells. It also accelerated tumor formation of L02 cells in BALB/c nude mice. Furthermore, Notch signaling components were upregulated in HBx-expressing L02 cells compared to normal L02 cells. However, blocking Notch signaling with a γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT) attenuated cell growth, shortened the S phase of cell cycle and promoted apoptosis of HBx-expressing L02 cell in a dose- and time-dependent manner, but normal L02 cells were not significantly affected by Notch signaling blocking. Therefore, our findings demonstrate that HBx could promote the growth of human non-tumor hepatic cell line L02 cells both in vitro and in vivo, which may require the activation of Notch signaling pathway. [ABSTRACT FROM AUTHOR]