Signal Transducer And Activator Of Transcription 3 Research Articles

Granulocyte Colony Stimulating Factor Enhances Decidualization Process of Endometrial Stromal Cells Through STAT3/HOXA10 Axis.

Recurrent implantation failure (RIF) is characterized by the repeated failure of implantation, often linked to impaired endometrial receptivity. This study investigates how granulocyte colony-stimulating factor (G-CSF) promotes endometrial stromal cell decidualization. THESCs (human telomerase reverse transcriptase-immortalized endometrial stromal cells) were used as an in vitro cell model to induce decidualization. The effects of G-CSF on the expression of decidualization genes and apoptosis during decidualization were examined. Additionally, a chemical inhibitor of signal transducer and activator of transcription 3 (STAT3) and the small interfering RNA (siRNA) targeting Homeobox A10 (Hoxa10) were employed to explore the involvement of the STAT3/HOXA10 axis in the action of G-CSF. G-CSF promoted decidualization markers expression and suppressed apoptosis in THESCs Treatment with G-CSF enhanced STAT3 activation during decidualization induction. STAT3 inhibition diminished the effects of G-CSF on decidualization marker expression and apoptosis suppression. Furthermore, it was demonstrated that G-CSF increased Hoxa10 expression in a STAT3-dependent manner. Silencing Hoxa10 abrogated the effects of G-CSF on promoting decidualization. G-CSF enhances decidualization of endometrial stromal cells via STAT3/HOXA10 axis activation. These findings suggest that optimal G-CSF delivery strategies could improve endometrial receptivity in RIF patients.

Co-Inhibition of tGLI1 and GP130 Using FDA-Approved Ketoconazole and Bazedoxifene Is Synergistic Against the Growth and Metastasis of HER2-Enriched and Triple-Negative Breast Cancers

Breast cancer stem cells (CSCs) are resistant to most cancer therapeutics and contribute to tumor recurrence and metastasis. Two breast CSC-promoting transcription factors, truncated glioma-associated oncogene homolog 1 (tGLI1) and signal transducer and activator of transcription 3 (STAT3), have been reported to be frequently co-expressed in HER2-enriched breast cancer and triple-negative breast cancer (TNBC), undergo protein-protein interactions for gene regulation and activation, and functionally cooperate to promote breast CSCs. STAT3 can be activated by activated interleukin-6 receptor/glycoprotein-130 (IL-6R/GP130). Co-targeting of tGLI1 and IL-6R/GP130 has not been investigated in breast cancer or any tumor type. Here, we report that tGLI1 and GP130 are co-overexpressed in the majority of HER2-enriched breast cancers and TNBCs at 53.8% and 44.4%, respectively. tGLI1+IL-6/IL-6R/GP130 signaling is frequently co-enriched and co-activated in HER2-enriched breast cancer and TNBC when compared to luminal subtypes. tGLI1+GP130 co-overexpression strongly promotes CSCs of HER2-enriched breast cancer and TNBC. FDA-approved tGLI1 inhibitor Ketoconazole and GP130 inhibitor Bazedoxifene synergize against breast cancer proliferation and CSC phenotypes in vitro and reduce TNBC tumor growth and metastatic burden in vivo. Our study demonstrates, for the first time, that co-targeting tGLI1 and IL-6R/GP130/STAT3 signaling pathways is synergistic against HER2-enriched breast cancer and TNBC, warranting future clinical investigations.

PF4 Silencing Promotes Trophoblast Cell Proliferation, Migration, Invasion and EMT by Regulating SOCS3/STAT3 Signaling Pathway.

Recurrent Miscarriage (RM) is a chronic and heterogeneous autoimmune disease. Platelet factor 4 (PF4) has been found to be involved in the pathogenesis of RM. We aimed to explore the role and mechanism of PF4 on trophoblasts in RM in vitro. In this study, the expression of PF4 and PF4 receptor CXC chemokine receptor 3 (CXCR3) in the placentas of patients with RM were analyzed by RT-qPCR and western blotting. Serum PF4 level was tested by ELISA. Following PF4 silencing and SOCS3 overexpression in HTR-8/SVneo cells, cell proliferation was detected by CCK-8, colony formation, and EDU assays. Wound healing and transwell assays separately evaluated cell migration and invasion. Immunofluorescence assay determined E-cadherin expression. Tube formation assay was used to measure the angiogenesis. Western blotting examined the expression of metastasis, epithelial-mesenchymal transition (EMT) and suppressor of cytokine signaling 3 (SOCS3)/signal transducer and activator of transcription 3 (STAT3) signaling-associated proteins. The results revealed that PF4 displayed increased expression in placental villus tissues of RM patients. Serum PF4 level was also elevated in RM patients. PF4 silencing promoted the proliferation, migration, invasion, EMT, and angiogenesis of HTR-8/SVneo cells. Additionally, PF4 knockdown downregulated SOCS3 expression to activate STAT3 signaling. SOCS3 overexpression countervailed the effects of PF4 deficiency on HTR-8/SVneo cells. In summary, PF4 participated in the proliferation, migration, invasion, EMT and angiogenesis of trophoblast cells by modulating the SOCS3/STAT3 signaling pathway, indicating that targeting the PF4/SOCS3/STAT3 pathway could be a novel therapy for RM.

α-Pyrrolidinooctanophenone facilitates activation of human microglial cells via ROS/STAT3-dependent pathway.

Pyrrolidinophenone derivatives (PPs) are amphetamine-like designer drugs containing a pyrrolidine ring, and their adverse effects resemble those of methamphetamine (METH). Microglial activation has been recently suggested as a key event in eliciting the adverse effects against dysfunction of the central nervous system. The aim of this study is to clarify the mechanisms of microglial activation induced by PPs. We employed the human microglial cell line HMC3 to assess microglial activation induced by PPs and evaluated the capacities for proliferation and interleukin-6 (IL-6) production that are characteristic features of the activation events. The WST-1 assay indicated that viability of HMC3 cells was increased by treatment with sublethal concentrations (5-20µM) of α-pyrrolidinooctanophenone (α-POP), a highly lipophilic PP, whereas it was decreased by treatment with concentrations above 40µM. Treatment with sublethal α-POP concentrations up-regulated the expression and secretion of IL-6. Additionally, α-POP-induced increase in cell viability was restored by pretreating with N-acetyl-L-cysteine, a reactive oxygen species (ROS) scavenger, and stattic, an inhibitor of signal transducer and activator of transcription 3 (STAT3), respectively, suggesting that activation of the ROS/STAT3 pathway is involved in the α-POP-induced activation of HMC3 cells. The increases in cell viability were also observed in HMC3 cells treated with other α-POP derivatives and METH. These results suggest that enhanced productions of ROS and IL-6 are also involved in microglial activation by drug treatment and that HMC3 cell-based system is available to evaluate accurately the microglial activation induced by abused drugs.

In vitro colonic fermentation of fermented Radix Astragali by Poria cocos and anti-hyperuricemia mechanism based on network pharmacology and experiment verification

AimThis research aimed to probe the effects of fecal microbiota and Lactobacillus acidophilus on the metabolism of Radix Astragali (RA) and Poria cocos solid fermenting Radix Astragali (FRA). It further explores pharmacological effects of RA, Poria cocos, and FRA on HUA mouse model and the mechanisms in HUA treatment.MethodsFecal microbiota and Lactobacillus acidophilus were used to ferment FRA and RA in vitro to probe the impacts of microbiota on the metabolism of active compound. A HUA mouse model was used to carry out pharmacodynamic experiment of anti-hyperuricemia. Network pharmacology and molecular docking was utilized to elucidate the underlying mechanisms of RA and Poria cocos in the treatment of HUA.ResultsThe results indicated that astragaloside IV (AG IV), total saponins, and flavonoids continuously decreased in FRA and RA during 48 h fecal microbiota colonic fermentation. During Lactobacillus acidophilus fermentation, in FRA, the content of AG IV peaked at 12 h with a value of 1.14 ± 0.20 mg/g; total saponins and flavonoids reached the highest values of 136.34 ± 6.15 mg/g at 12 h and 6.35 ± 0.06 mg/g at 6 h; AG IV and total saponins reached the highest values 0.63 ± 0.05 mg/g and 115.12 ± 4.12 mg/g at 12 h and 24 h in RA, respectively; and total flavonoids consecutively decreased. The counts of Lactobacillus acidophilus increased significantly in FRA compared with RA. Pharmacodynamic outcomes revealed that FRA effectively reduced blood levels of uric acid (UA), triglycerides (TG), xanthine oxidase (XOD), alanine aminotransferase (ALT), and aspartate transaminase (AST) in HUA mice, exerting protective effects on the liver and kidney. Network pharmacology showed that there were 93 common targets for RA, Poria cocos, and HUA with the top five core targets tumor necrosis factor (TNF), signal transducer and activator of transcription 3 (STAT3), cysteinyl aspartate specific proteinase 3 (CASP3), jun proto-oncogene (JUN), and estrogen receptor 1 (ESR1). Molecular docking analysis revealed that AG IV, calycosin and formononetin bond well to the core targets.ConclusionThis research revealed the interaction of RA and FRA with fecal microbiota and Lactobacillus acidophilus, RA and Poria cocos were featured with multiple components, target points, and signaling pathways in HUA treatment, which provided fresh insights for further HUA therapeutics.

Siwu decoction mitigates radiation-induced immune senescence by attenuating hematopoietic damage

BackgroundTo investigate the long term effects of ionizing radiation (IR) on hematopoietic stem/progenitor cells (HSPCs), immune tissues and cells, and the effects of Siwu decoction (SWD) on immune senescence mice.MethodsC57BL/6 J mice were exposed to 6.0 Gy 60Co γ irradiation. After 8-weeks of IR, SWD (5, 10, 20 g/kg/d) was administered for 30 days. The changes of HSPCs in bone marrow (BM) and T, B type lymphocyte and natural killer (NK) cells in spleen were detected by flow cytometry. The changes of peripheral blood cells were also examined. Hematoxylin–eosin staining were used to detect the pathological lesions of hippocampus, spleen and thymus tissues. Absolute mouse telomere length quantification qPCR assay kit was used to measure the telomere length of BM cells. The expression of factors associated with inflammation and aging such as p16, β-galactosidase in spleen, thymus and BM was determined.ResultsAdministration of SWD could increase the proportion of LSK (Lin−, Sca-1 + , c-Kit−), multipotent progenitor cells and multipotent progenitor cells and decrease the proportion of common myeloid progenitors and granulocyte–macrophage progenitors in BM. The proportion of B cells and NK cells in spleen and the content of white blood cells, red blood cells, hemoglobin, lymphocytes and eosinophils in peripheral blood were increased, at the same time, the proportion of neutrophils and monocytes was reduced by SWD. The pathological lesions of hippocampus, spleen and thymus were improved. The expression of p16 and β-galactosidase in spleen, thymus and BM was reduced and shortening of the telomere of BM cells was inhibited after administration. In addition, SWD could reduce the content of Janus activated kinase (JAK) 1, JAK2 and signal transducer and activator of transcription 3 (STAT3) in BM and spleen.ConclusionsSWD could slow down IR-induced immune senescence by improving hematopoietic and immunologic injury. SWD might reduce the inflammation level of BM hematopoietic microenvironment by acting on JAK/STAT signaling pathway, while the immune damage of mice was improved by affecting the differentiation of HSPCs. The remission of hematopoietic and immunologic senescence was further demonstrated at the overall level.Graphical

FOXA1 knockdown alleviates inflammation and enhances osteogenic differentiation of periodontal ligament stem cells via STAT3 pathway

BackgroundEvidence has confirmed that forkhead box protein A1 (FOXA1) inhibits the osteogenic differentiation of bone marrow mesenchymal stem cells. However, whether FOXA1 regulates the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) to participate in periodontitis process is unclear.MethodsLipopolysaccharide (LPS) was used to treat hPDLSCs to mimic inflammation environments. FOXA1 expression was examined by quantitative real-time PCR and western blot. The levels of IL-6 and TNF-α were evaluated by quantitative real-time PCR, ELISA and immunohistochemistry staining. hPDLSCs osteogenic differentiation was assessed by measuring alkaline phosphatase activity, alizarin red S intensity and the levels of osteogenic differentiation-related markers. Besides, the expression of signal transducer and activator of transcription 3 (STAT3) pathway-related markers were examined by western blot and immunofluorescence staining.ResultsFOXA1 was upregulated in the periodontal ligament tissues of periodontitis patients, and its knockdown enhanced osteogenic differentiation of hPDLSCs. Besides, downregulation of FOXA1 suppressed inflammation levels in LPS-induced hPDLSCs. Also, FOXA1 silencing promoted the osteogenic differentiation of LPS-induced hPDLSCs by the inactivation of STAT3 pathway.ConclusionOur data confirmed that knockdown of FOXA1 attenuated inflammation and enhanced osteogenic differentiation of LPS-induced hPDLSCs by regulating STAT3 pathway, indicating that FOXA1 might be a target for periodontitis treatment.

Sea Hare Hydrolysate Reduces PD‐L1 Levels in Cancer Cells and Mitigates Rheumatoid Arthritis Ina Collagen‐Induced Arthritis Mouse Model

ABSTRACTOur previous study highlighted the anticancer potential of sea hare hydrolysate (SHH), particularly its role in regulating macrophage polarization and inducing pyroptotic death in lung cancer cells through the inhibition of signal transducer and activator of transcription 3 (STAT3). These findings prompted us to investigate additional features of immune‐oncology (I‐O) agents or adjuvants, such as programmed cell death protein 1 (PD‐1)/programmed death ligand 1 (PD‐L1) inhibition and their association with rheumatoid arthritis (RA) risk, to explore the potential of SHH as an I‐O agent or adjuvant. In this study, we investigated the effects of SHH on PD‐L1 levels in various cancer cell types and assessed its effectiveness in treating RA, a common side effect of I‐O agents. Our results showed a marked reduction in PD‐L1 levels in multiple cancer cell lines and decreased PD‐1 and PD‐L1 levels in tumor‐associated macrophages. In a mouse model with collagen‐induced arthritis (CIA), SHH exhibited anti‐inflammatory effects comparable to methotrexate (MTX), a first‐line treatment for RA. Both the SHH and MTX groups had significantly lower arthritis scores and paw thickness compared to the CIA group. Additionally, SHH or MTX treatment effectively reduced elevated levels of anticollagen type II (CII) antibodies and proinflammatory cytokines (IL‐1β, IL‐6, and TNF‐α). Histopathological analysis revealed that SHH and MTX treatments notably mitigated arthritic inflammation, synovial hyperplasia, and loss of articular cartilage and bone. Micro‐CT scans showed reduced articular destruction in the SHH and MTX groups. These findings indicate that SHH treatment decreases PD‐L1 levels in cancer cells and reduces the severity of CIA by exerting anti‐inflammatory effects. Therefore, SHH holds promise as an I‐O agent without side effects such as exacerbation of RA.

Inhibition of peritendinous adhesion through targeting JAK2-STAT3 signaling pathway: The therapeutic potential of AG490

Peritendinous adhesion is a common complication following tendon injury repair, posing a significant clinical challenge that requires urgent attention. The primary cause of peritendinous adhesion is the excessive deposition of collagen matrix due to the abnormal proliferation of fibroblasts in an inflammatory state. Janus kinase2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) are key signaling molecules involved in cell proliferation and fibrosis development in various organs. However, the role of the JAK-2 and STAT3 signaling pathways in peritendinous adhesion fibrosis remains unclear. In our study, we first observed upregulation of p-JAK2 and p-STAT3 proteins in human peritendinous adhesion specimens and rat peritendinous adhesion models. In vitro, the JAK2/STAT3 pathway inhibitor AG490 effectively inhibited TGF-β1-induced fibroblast proliferation. Wound healing and transwell assays demonstrated that AG490 suppressed TGF-β1-induced fibroblast migration. Furthermore, we found that AG490 decreased the expression of pro-inflammatory factors, including IL-1β and TNF-α, as well as extracellular matrix (ECM) proteins in fibroblasts under TGF-β1 stimulation. In vivo, histological staining showed that AG490 prevented fibrous tissue formation in a rat model of tendon injury. Moreover, AG490 inhibited the overexpression of pro-inflammatory factors IL-1β and TNF-α, as well as ECM in the peritendinous adhesions. In conclusion, AG490 inhibited fibrosis and inflammation in injured tendons by targeting the JAK2-STAT3 signaling pathway, presenting a promising strategy for the prophylaxis of peritendinous adhesions.

Cryptotanshinone Suppresses the STAT3/BCL-2 Pathway to Provoke Human Bladder Urothelial Carcinoma Cell Death.

Bladder cancer is one of the most common human malignancies worldwide. Aberrant activation of signal transducer and activator of transcription 3 (STAT3) is crucial to driving malignant progression and predicting poor prognosis of multiple human cancers, including bladder cancer, making STAT3 a promising target of cancer therapeutics. Cryptotanshinone (CTS) is an anticancer ingredient of Danshen (Salvia miltiorrhiza), a top-graded Chinese medicinal herb. However, whether CTS targets STAT3 to exert its cytotoxic effect on human bladder cancer remains unknown. Herein, we demonstrated that CTS is cytotoxic to multiple human urinary bladder transitional cell carcinoma (TCC) cell lines while sparing normal human urothelial cells. CTS provoked apoptosis-dependent bladder TCC cytotoxicity, as apoptosis blockage by z-VAD-fmk markedly rescued the clonogenicity of CTS-treated cells. Besides, CTS was found to suppress constitutive and interleukin 6-inducible activation of STAT3, evidenced by the downregulation of STAT3 tyrosine 705 phosphorylation and BCL2, a recognized STAT3 transcriptional target. Notably, ectopic expression of a dominant-active STAT3 mutant (STAT3-C) or BCL-2 alleviated CTS-induced apoptosis and clonogenicity inhibition, thus confirming STAT3 blockade as a pivotal mechanism of CTS's cytotoxic action on bladder TCC cells. Lastly, immunoblotting revealed that CTS lowered the levels of active JAK2, an upstream kinase that mediates STAT3 tyrosine 705 phosphorylation. Altogether, we conclude that the blockade of the JAK2/STAT3/BCL-2 antiapoptotic signaling axis is a vital mechanism whereby CTS provokes bladder cancer cytotoxicity. The current evidence implicates CTS's potential to be translated into a bladder cancer therapeutic agent.

Effects of miR-214-5p and miR-21-5p in hypoxic endometrial epithelial-cell-derived exosomes on human umbilical cord mesenchymal stem cells

BACKGROUND Thin endometrium seriously affects endometrial receptivity, resulting in a significant reduction in embryo implantation, and clinical pregnancy and live birth rates, and there is no gold standard for treatment. The main pathophysiological characteristics of thin endometrium are increased uterine arterial blood flow resistance, angiodysplasia, slow growth of the glandular epithelium, and low expression of vascular endothelial growth factor, resulting in endometrial epithelial cell (EEC) hypoxia and endometrial tissue aplasia. Human umbilical cord mesenchymal stem cells (HucMSCs) promote repair and regeneration of damaged endometrium by secreting microRNA (miRNA)-carrying exosomes. However, the initiation mechanism of HucMSCs to repair thin endometrium has not yet been clarified. AIM To determine the role of hypoxic-EEC-derived exosomes in function of HucMSCs and explore the potential mechanism. METHODS Exosomes were isolated from normal EECs (EEC-exs) and hypoxia-damaged EECs (EECD-exs), before characterization using Western blotting, nanoparticle-tracking analysis, and transmission electron microscopy. HucMSCs were cocultured with EEC-exs or EECD-exs and differentially expressed miRNAs were determined using sequencing. MiR-21-5p or miR-214-5p inhibitors or miR-21-3p or miR-214-5p mimics were transfected into HucMSCs and treated with a signal transducer and activator of transcription 3 (STAT3) activator or STAT3 inhibitor. HucMSC migration was assessed by Transwell and wound healing assays. Differentiation of HucMSCs into EECs was assessed by detecting markers of stromal lineage (Vimentin and CD13) and epithelial cell lineage (CK19 and CD9) using Western blotting and immunofluorescence. The binding of the miRNAs to potential targets was validated by dual-luciferase reporter assay. RESULTS MiR-21-5p and miR-214-5p were lowly expressed in EECD-ex-pretreated HucMSCs. MiR-214-5p and miR-21-5p inhibitors facilitated the migratory and differentiative potentials of HucMSCs. MiR-21-5p and miR-214-5p targeted STAT3 and protein inhibitor of activated STAT3, respectively, and negatively regulated phospho-STAT3. MiR-21-5p- and miR-214-5p-inhibitor-induced promotive effects on HucMSC function were reversed by STAT3 inhibition. MiR-21-5p and miR-214-5p overexpression repressed HucMSC migration and differentiation, while STAT3 activation reversed these effects. CONCLUSION Low expression of miR-21-5p/miR-214-5p in hypoxic-EEC-derived exosomes promotes migration and differentiation of HucMSCs into EECs via STAT3 signaling. Exosomal miR-214-5p/miR-21-5p may function as valuable targets for thin endometrium.

Postbiotics From Lactobacillus Johnsonii Activates Gut Innate Immunity to Mitigate Alcohol-Associated Liver Disease.

Prolonged alcohol consumption disrupts the gut microbiota and the immune system, contributing to the pathogenesis of alcohol-associated liver disease (ALD). Probiotic-postbiotic intervention strategies can effectively relieve ALD by maintaining gut homeostasis. Herein, the efficacy of heat-killed Lactobacillus johnsonii (HKLJ) in mitigating alcoholic liver damage is demonstrated in mouse models of ALD. The gut-liver axis is identified as a pivotal pathway for the protective effects of L. johnsonii against ALD. Specifically, HKLJ is found to upregulate the expression of intestinal lysozymes, thereby enhancing the production of immunoregulatory substances from gut bacteria, which subsequently activated the Nucleotide-binding oligomerization domain 2 (NOD2)-interleukin (IL-23)-IL-22 innate immune axis. The elevated IL-22 upregulated the antimicrobial peptide synthesis to maintain intestinal homeostasis and moreover activated the Signal transducer and activator of Transcription3 (STAT3) pathway in the liver to facilitate the repair of hepatic injuries. The heat-killed L. johnsonii provoked immunity helps correct the gut microbiota dysbiosis, specifically by reversing the reduction of butyrate-producing bacteria (such as Faecalibaculum rodentium) and the expansion of opportunistic pathogens (such as Helicobacter sp. and Pichia kudriavzevii) induced by ethanol. The findings provide novel insights into the gut microbiota-liver axis that may be leveraged to enhance the treatment of ALD.

Pharmacotherapeutic potential of bilobetin to combat chromium induced hepatotoxicity via regulating TLR-4, Nrf-2/Keap-1, JAK1/STAT3 and NF-κB pathway: A pharmacokinetic and molecular dynamic approach

BackgroundChromium (Cr) is one of the top-notch noxious heavy metals that is documented to exert deleterious effects on various body organs including the liver. Bilobetin (BLB) is a natural flavonoid which exhibits a wide range of medicinal properties. AimThis trial was executed to investigate the pharmacotherapeutic potential of BLB to avert Cr instigated hepatotoxicity via modulating TLR4, JAK1/STAT3, Nrf-2/Keap-1 and NF-κB pathway. Research layoutOur trial was executed on thirty-six male albino rats that were segregated into four equal groups including the control, Cr (10 mg/kg), Cr (10 mg/kg) + BLB (12 mg/kg) and BLB (12 mg/kg) alone treated group. Various biochemical parameters were assessed by using qRT-PCR, molecular docking, molecular dynamic simulation and histological approaches. FindingsOur results revealed that Cr administration significantly impaired the health of hepatic tissues by reducing the gene expression of Nrf-2 and its downregulating genes while promoting the levels of oxidative stress markers (ROS and MDA). Moreover, Cr administration upregulated the hepatic enzymes including ALT, GGT, AST, and ALP while concurrently decreasing the levels of total protein and albumin. Cr exposure also elevated the gene expression of pro-inflammatory cytokines including toll-like receptor 4 (TLR4), high mobility group box 1 (HMGB1) nuclear factor kappa B (NF-κB), Janus kinase 1 (JAK1), signal transducer and activator of transcription 3 (STAT3), tumor necrosis factor alpha (TNF-α), C-reactive proteins, interferon-gamma inducible protein-10 (IP-10), Interleukin beta-1(IL-1β), monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2). Hepatic apoptosis was observed to be elevated following the Cr intoxication. Nonetheless, BLB treatment remarkably alleviated the hepatic damages via regulating the biochemical as well as histological profile of liver. Our findings are further endorsed by molecular docking analysis that demonstrated that BLB exhibit strong binding affinity to Keap-1 and STAT3 thus supporting its efficient hepatoprotective potential. ConclusionBLB protected the hepatic tissues via regulating Cr induced impairments. These findings were confirmed by molecular docking and molecular dynamic simulation analysis.

Inhibition of PA28γ expression can alleviate osteoarthritis by inhibiting endoplasmic reticulum stress and promoting STAT3 phosphorylation.

Osteoarthritis (OA) is a common degenerative disease. PA28γ is a member of the 11S proteasome activator and is involved in the regulation of several important cellular processes, including cell proliferation, apoptosis, and inflammation. This study aimed to explore the role of PA28γ in the occurrence and development of OA and its potential mechanism. A total of 120 newborn male mice were employed for the isolation and culture of primary chondrocytes. OA-related indicators such as anabolism, catabolism, inflammation, and apoptosis were detected. Effects and related mechanisms of PA28γ in chondrocyte endoplasmic reticulum (ER) stress were studied using western blotting, real-time polymerase chain reaction (PCR), and immunofluorescence. The OA mouse model was established by destabilized medial meniscus (DMM) surgery, and adenovirus was injected into the knee cavity of 15 12-week-old male mice to reduce the expression of PA28γ. The degree of cartilage destruction was evaluated by haematoxylin and eosin (HE) staining, safranin O/fast green staining, toluidine blue staining, and immunohistochemistry. We found that PA28γ knockdown in chondrocytes can effectively improve anabolism and catabolism and inhibit inflammation, apoptosis, and ER stress. Moreover, PA28γ knockdown affected the phosphorylation of IRE1α and the expression of TRAF2, thereby affecting the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signalling pathways, and finally affecting the inflammatory response of chondrocytes. In addition, we found that PA28γ knockdown can promote the phosphorylation of signal transducer and activator of transcription 3 (STAT3), thereby inhibiting ER stress in chondrocytes. The use of Stattic (an inhibitor of STAT3 phosphorylation) enhanced ER stress. In vivo, we found that PA28γ knockdown effectively reduced cartilage destruction in a mouse model of OA induced by the DMM surgery. PA28γ knockdown in chondrocytes can inhibit anabolic and catabolic dysregulation, inflammatory response, and apoptosis in OA. Moreover, PA28γ knockdown in chondrocytes can inhibit ER stress by promoting STAT3 phosphorylation.

Identification of STAT3 and MYC as critical ferroptosis-related biomarkers in septic cardiomyopathy: a bioinformatics and experimental study.

Ferroptosis is the well-known mechanism of septic cardiomyopathy (SCM). Bioinformatics analysis was employed to identify ferroptosis-related SCM differentially expressed genes (DEG). DEGs' functional enrichment was explored. Weighted gene co-expression network analysis (WGCNA) was employed to form gene clusters. The identified hub genes, signal transducer and activator of transcription 3 (STAT3) and myelocytomatosis (MYC) were further evaluated by generating receiver operator characteristic (ROC) curves and a nomogram prediction model. Additionally, survival rate, cardiac damage markers, and cardiac function and ferroptosis markers were evaluated in septic mouse model. STAT3 and MYC levels were measured in SCM heart tissue via immunohistochemical (IHC) staining, real-time polymerase chain reaction (qPCR) and western blot analysis. Analysis identified 225 DEGs and revealed 22 intersected genes. Of the 7 hub genes, STAT3 and MYC showed enrichment in septic heart tissue and a strong predicative ability based on AUC values. Cardiac damage, iron metabolism, and lipid peroxidation occurred in the SCM model. By experiments, STAT3 and MYC expression was increased in the SCM model. Impairment was reversed with a ferroptosis inhibitor, Fer-1. As conclusion, STAT3 and MYC are related with ferroptosis and may serve as potential SCM predictor indicators. KEY MESSAGES: Septic cardiomyopathy (SCM) often leads to high mortality in septic patients, and the diagnostic criteria still remains unclear. Ferroptosis as the pathogenic mechanism of SCM could help predict its progression and clinical outcomes. STAT3 and MYC are related with ferroptosis and may serve as potential SCM predictor biomarkers.

Effect of Comparable Carbon Chain Length Short- and Branched-Chain Fatty Acids on Adipokine Secretion from Normoxic and Hypoxic Lipopolysaccharide-Stimulated 3T3-L1 Adipocytes.

Background: Microbial fermentation of non-digestible carbohydrates and/or protein produces short-chain fatty acids (SCFA), whereas branched-chain fatty acids (BCFA) are produced from protein fermentation. The effects of individual SCFA and BCFA of comparable carbon chain length on adipocyte inflammation have not been investigated. Objective: To compare the effects of SCFA and BCFA on inflammatory mediator secretion in an adipocyte cell culture model designed to recapitulate obesity-associated adipocyte inflammation under normoxic and hypoxic conditions. Methods: The 3T3-L1 adipocytes were cultured (24 h) without (Control, Con) and with 1 mmol/L of SCFA (butyric acid (But) or valeric acid (Val)) or 1 mmol/L of BCFA (isobutyric acid (IsoBut) or isovaleric acid (IsoVal)) and were unstimulated (cells alone, n = 6/treatment), or stimulated with 10 ng/mL lipopolysaccharide (LPS, inflammatory stimulus, n = 8/treatment) or 10 ng/mL LPS + 100 µmol/L of the hypoxia memetic cobalt chloride (LPS/CC, inflammatory/hypoxic stimulus, n = 8/treatment). Results: Compared to Con + LPS, But + LPS reduced secreted protein levels of interleukin (IL)-1β, IL-6, macrophage chemoattractant protein (MCP)-1/chemokine ligand (CCL)2, MCP3/CCL7, macrophage inflammatory protein (MIP)-1α/CCL3 and regulated upon activation, normal T cell expressed, and secreted (RANTES)/CCL5 and decreased intracellular protein expression of the ratio of phosphorylated to total signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappa B (NFκB) p65 (p < 0.05). Val + LPS reduced IL-6 secretion and increased MCP-1/CCL2 secretion compared to Con + LPS and exhibited a different inflammatory mediator secretory profile from But + LPS (p < 0.05), indicating that individual SCFA exert individual effects. There were no differences in the secretory profile of the BCFA IsoBut + LPS and IsoVal + LPS (p > 0.05). Alternatively, under inflammatory hypoxic conditions (LPS/CC) Val, IsoVal, and IsoBut all increased secretion of IL-6, MCP-1/CCL2 and MIP-1α/CCL3 compared to Con (p < 0.05), whereas mediator secretion did not differ between But and Con (p > 0.05), indicating that the proinflammatory effects of SCFA and BCFA was attenuated by But. Interestingly, But + LPS/CC decreased STAT3 activation versus Con + LPS/CC (p < 0.05). Conclusions: The decreased secretion of inflammatory mediators that is attributable to But highlights the fact that individual SCFA and BCFA exert differential effects on adipocyte inflammation under normoxic and hypoxic conditions.

Humanin-G Ameliorates Hemorrhage-Induced Acute Lung Injury in Mice Through AMPKα1-Dependent and -Independent Mechanisms.

Background/Objectives: The severity of acute lung injury is significantly impacted by age and sex in patients with hemorrhagic shock. AMP-activated protein kinase (AMPK) is a crucial regulator of energy metabolism but its activity declines with aging. Humanin is a mitochondrial peptide that exerts cytoprotective effects in response to oxidative stressors and is associated with longevity. Using a mouse model of hemorrhagic shock that mimics the clinical condition of adult patients, we investigated whether treatment with a humanin analog, humanin-G, mitigates lung injury and whether its mechanisms of action are dependent on the catalytic AMPKα1 subunit activation. Methods: Male and female AMPKα1 wild-type (WT) and knock-out (KO) mice (8-13 months old) were subjected to hemorrhagic shock by blood withdrawal, followed by resuscitation with shed blood and lactated Ringer's solution. The mice were treated with PEGylated humanin-G or vehicle and euthanized 3 h post-resuscitation. Results: Sex- and genotype-related differences were observed after hemorrhagic shock as lung neutrophil infiltration was more pronounced in the male AMPKα1 WT mice than the female WT mice; also, the male AMPKα1 KO mice experienced a significant decline in mean arterial blood pressure when compared to the male WT mice after resuscitation. The scores of histological lung injury were similarly elevated in all the male and female AMPKα1 WT and KO mice when compared to the control mice. At molecular analysis, acute lung injury was associated with the downregulation of AMPKα1/α2 catalytic subunits in the WT mice, whereas an increased activation of the signal transducer and activator of transcription-3 (STAT3) was observed in all the vehicle-treated groups. The in vivo administration of humanin-G ameliorated histological lung damage in all the groups of animals and ameliorated mean arterial blood pressure in the male AMPKα1 KO mice. The in vivo administration of humanin-G lowered lung neutrophil infiltration in the male and female AMPKα1 WT mice only but not in the KO mice. The beneficial results of humanin-G correlated with the lung cytosolic and nuclear activation of AMPKα in the male and female AMPKα1 WT groups, whereas STAT3 activation was not modified. Conclusions: In adult age, hemorrhage-induced acute lung injury manifests with sex-dependent characteristics. Humanin-G has therapeutic potential and the AMPKα1subunit is an important requisite for its inhibitory effects on lung leucosequestration, but not for the amelioration of lung alveolar structure or the hemodynamic effects of the peptide.

RNA binding protein CUGBP2/ETR-3 regulates STAT3 alternative splicing

Signal transducer and activator of transcription 3 (STAT3) is a multifactorial regulator involved in many biological responses. Alternative splicing of STAT3 pre-mRNA leads to an internal 50-nucleotide deletion of exon 23 selecting an alternative 3’ acceptor site, resulting in the generation of two splicing isoforms, STAT3α and STAT3β. STAT3β lacks 55 amino acid-residue transactivation domain at the C-terminal of STAT3α replacing seven unique amino acids. Although STAT3β was originally thought to be a dominant negative isoform of STAT3α, accumulating evidence have shown that STAT3β possesses both its unique functions and those that overlap with STAT3α in fundamental cellular processes. However, much remains unknown about STAT3 pre-mRNA alternative splicing in determining the balance between STAT3 isoforms. In this study, we identified cis-regulatory elements and CUGBP2/ETR-3 as a novel trans-acting factor that regulates STAT3 alternative splicing. Our findings demonstrate that STAT3 splicing can be modulated by CUGBP2 via association with UG-rich elements of intron 22, providing a novel insight into the mechanism of STAT3 alternative splicing. CUGBP2 would be a crucial molecule regulating the balance of STAT3 isoform expression, thus targeting CUGBP2 and its recognition sequences in intron 22 of STAT3 might impact on various biological processes regulated by STAT3 signaling pathway.

Cross-sectional analysis of blood leukocyte responsiveness to interleukin-10 and interleukin-6 across age and physical activity level

Abstract Objectives To determine how the anti-inflammatory actions of interleukin-10 (IL-10) and IL-6 differ across age and physical activity levels. Methods Using a cross-sectional design, fasted blood samples were obtained from younger physically inactive (YI: n=10, age: 22.7 ± 3.7 years, BMI: 24.8 ± 4.8 kg/m2, &lt;150 min of weekly moderate-to-vigorous physical activity [MVPA]), younger highly active (YA: n=11 varsity cross country running athletes, 20.7 ± 2.7 years, 21.1 ± 1.8 kg/m2, &gt;300 min of weekly MVPA), and older highly active (OA: 12, 56.0 ± 10.3 years, 22.8 ± 3.2 kg/m2, &gt;300 min of weekly MVPA) individuals and analyzed for leukocyte counts, IL-10 and IL-6-related signaling, and cytokine secretion ex vivo. Results Total white blood cells and monocytes were similar between groups (p=0.8) but YA and OA had lower lymphocyte counts than YI (p&lt;0.01). The ability of IL-10 (1 ng/mL) to phosphorylate signal transducer and activator of transcription 3 (STAT3) in CD14 monocytes was greater in YA vs. YI (p&lt;0.03) despite YA having lower IL-10 receptor expression (p&lt;0.01). IL-6 (10 ng/mL) mediated STAT3 phosphorylation in CD4 lymphocytes was higher in OA compared YI (p&lt;0.01), with a similar tendency observed for YA vs. YI (p=0.08). Despite enhanced responsiveness of STAT3 to IL-10/6 in active individuals, the ability of IL-10/6 to inhibit tumor necrosis factor-alpha (TNF-⍺) secretion from lipopolysaccharide-stimulated whole-blood was similar between groups. Conclusions Highly active younger and older individuals demonstrate enhanced IL-10- and IL-6-mediated activation of immune cell STAT3. Although the ability of IL-10/6 to inhibit TNF-⍺ secretion appeared unimpacted by activity level, anti-inflammatory cytokine actions were preserved in older active individuals.

Gallein, G protein βγ subunits inhibitor, suppresses the TGF-α-induced migration of hepatocellular carcinoma cells via inhibition of the c-Jun N-terminal kinase.

G protein-coupled receptor (GPCR) signaling regulates a wide range of pathophysiological cell functions via G protein α and βγ subunits. Small molecules targeting the subunits of Gα and Gβγ have been developed as cancer therapeutics. We have previously reported that transforming growth factor-α (TGF-α) induces the migration of human hepatocellular carcinoma (HCC) HuH7 cells through the activation of AKT, p38 mitogen-activated protein kinase (MAPK), Rho-kinase and c-Jun N-terminal kinase (JNK). This study aims to determine whether Gβγ subunits regulate the TGF-α-induced migration of HCC HuH7 cells using gallein, a Gβγ subunits inhibitor. The Janus family of tyrosine kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) signaling pathway was also involved in the regulation of the migration. Gallein significantly reduced the TGF-α-induced cell migration. In contrast, fluorescein, a gallein-related compound that has no effect on Gβγ subunits, failed to affect the cell migration. Gallein suppressed the TGF-α-stimulated phosphorylation of JNK without affecting the phosphorylation of epidermal growth factor receptor, AKT, p38 MAPK, target protein of Rho-kinase and STAT3. Conversely, fluorescein did not attenuate the phosphorylation of JNK. These results strongly suggest that Gβγ subunits act as positive regulators in TGF-α-induced migration of HCC cells via the JNK signalling pathway.