Potential molecular patterns for tuberculosis susceptibility in diabetic patients with poor glycaemic control: a pilot study.

Type 2 diabetes (DM2) is an increasingly prevalent disease that challenges tuberculosis (TB) control strategies worldwide. It is significant that DM2 patients with poor glycemic control (PDM2) are prone to developing tuberculosis. Furthermore, elucidating the molecular mechanisms that govern this susceptibility is imperative to address this problem. Therefore, a pilot transcriptomic study was performed. Human blood samples from healthy controls (CTRL, HbA1c < 6.5%), tuberculosis (TB), comorbidity TB-DM2, DM2 (HbA1c 6.5-8.9%), and PDM2 (HbA1c > 10%) groups (n = 4 each) were analyzed by differential expression using microarrays. We use a network strategy to identify potential molecular patterns linking the differentially expressed genes (DEGs) specific for TB-DM2 and PDM2 (p-value < 0.05, fold change > 2). We define OSM, PRKCD, and SOCS3 as key regulatory genes (KRGs) that modulate the immune system and related pathways. RT-qPCR assays confirmed upregulation of OSM, PRKCD, and SOCS3 genes (p < 0.05) in TB-DM2 patients (n = 18) compared to CTRL, DM2, PDM2, or TB groups (n = 17, 19, 15, and 9, respectively). Furthermore, OSM, PRKCD, and SOCS3 were associated with PDM2 susceptibility pathways toward TB-DM2 and formed a putative protein-protein interaction confirmed in STRING. Our results reveal potential molecular patterns where OSM, PRKCD, and SOCS3 are KRGs underlying the compromised immune response and susceptibility of patients with PDM2 to develop tuberculosis. Therefore, this work paved the way for fundamental research of new molecular targets in TB-DM2. Addressing their cellular implications, and the impact on the diagnosis, treatment, and clinical management of TB-DM2 could help improve the strategy to end tuberculosis for this vulnerable population.

Bifidobacterium longum and Chlorella sorokiniana Combination Modulates IFN-γ, IL-10, and SOCS3 in Rotavirus-Infected Cells.

Rotavirus is the main cause of acute diarrhea in children up to five years of age. In this regard, probiotics are commonly used to treat or prevent gastroenteritis including viral infections. The anti-rotavirus effect of Bifidobacterium longum and Chlorella sorokiniana, by reducing viral infectivity and improving IFN-type I response, has been previously reported. The present study aimed to study the effect of B. longum and/or C. sorokiniana on modulating the antiviral cellular immune response mediated by IFN-γ, IL-10, SOCS3, STAT1, and STAT2 genes in rotavirus-infected cells. To determine the mRNA relative expression of these genes, HT-29 cells were treated with B. longum and C. sorokiniana alone or in combination, followed by rotavirus infection. In addition, infected cells were treated with B. longum and/or C. sorokiniana. Cellular RNA was purified, used for cDNA synthesis, and amplified by qPCR. Our results demonstrated that the combination of B. longum and C. sorokiniana stimulates the antiviral cellular immune response by upregulating IFN-γ and may block pro-inflammatory cytokines by upregulating IL-10 and SOCS3. The results of our study indicated that B. longum, C. sorokiniana, or their combination improve antiviral cellular immune response and might modulate pro-inflammatory responses.

Verapamil and tangeretin enhances the M1 macrophages to M2 type in lipopolysaccharide-treated mice and inhibits the P-glycoprotein expression by downregulating STAT1/STAT3 and upregulating SOCS3.

LPS induced sepsis is a complex process involving various immune cells and signaling molecules. Dysregulation of macrophage polarization and ROS production contributed to the pathogenesis of sepsis. PGP is a transmembrane transporter responsible for the efflux of a number of drugs and also expressed in murine macrophages. Natural products have been shown to decrease inflammation and expression of efflux transporters. However, no treatment is currently available to treat LPS induced sepsis. Verapamil and Tangeretin also reported to attenuate lipopolysaccharide-induced inflammation. However, the effects of verapamil or tangeretin on lipopolysaccharide (LPS)-induced sepsis and its detailed anti-inflammatory mechanism have not been reported. Here, we have determined that verapamil and tangeretin protects against LPS-induced sepsis by suppressing M1 macrophages populations and also through the inhibition of P-glycoprotein expression via downregulating STAT1/STAT3 and upregulating SOCS3 expression in macrophages. An hour before LPS (10 mg/kg) was administered; mice were given intraperitoneal injections of either verapamil (5 mg/kg) or tangeretin (5 mg/kg). The peritoneal macrophages from different experimental groups of mice were isolated. Hepatic, pulmonary and splenic morphometric analyses revealed that verapamil and tangeretin decreased the infiltration of neutrophils into the tissues. Verapamil and tangeritin also enhanced the activity of SOD, CAT, GRX and GSH level in all the tissues tested. verapamil or tangeretin pre-treated mice shifted M1 macrophages to M2 type possibly through the inhibition of P-glycoprotein expression via downregulating STAT1/STAT3 and upregulating SOCS3 expression. Hence, both these drugs have shown protective effects in sepsis via suppressing iNOS, COX-2, oxidative stress and NF-κB signaling in macrophages. Therefore, in our study we can summarize that mice were treated with either Vera or Tan before LPS administration cause an elevated IL-10 by the macrophages which enhances the SOCS3 expression, and thereby able to limits STAT1/STAT3 inter-conversion in the macrophages. As a result, NF-κB activity is also getting down regulated and ultimately mitigating the adverse effect of inflammation caused by LPS in resident macrophages. Whether verapamil or tangeretin offers such protection possibly through the inhibition of P-glycoprotein expression in macrophages needs clarification with the bio availability of these drugs under PGP inhibited conditions is a limitation of this study.

Exploring the clinical and cellular mechanisms of LncRNA-KCNQ1OT1/miR-29a-3p/SOCS3 molecular axis in cases of unexplained recurrent spontaneous abortion.

OBJECTIVE: The objective of this study is to explore the functions and mechanisms of the LncRNA-KCNQ1OT1/miR-29a-3p/SOCS3 molecular pathway in the context of unexplained recurrent spontaneous abortion (URSA). METHODS: We conducted qRT-PCR to assess the levels of LncRNA-KCNQ1OT1, miR-29a-3p, and SOCS3 in both abortion tissues from women who experienced URSA and healthy early pregnant women. A dual-luciferase assay was employed to investigate whether miR-29a-3p targets SOCS3. Furthermore, RNA IP and RNA Pull-Down assays were employed to confirm the interaction between KCNQ1OT1 and SOCS3 with miR-29a-3p. RNA FISH was used to determine the cellular localization of KCNQ1OT1. Additionally, trophoblast cells (HTR8/SVneo) were cultured and the CCK-8 assay was utilized to assess cell proliferation, while flow cytometry was employed to analyze cell apoptosis. RESULTS: Compared to abortion tissues obtained from healthy early pregnant individuals, those from women who experienced URSA displayed a notable downregulation of KCNQ1OT1 and SOCS3, accompanied by an upregulation of miR-29a-3p. Suppression of KCNQ1OT1 resulted in the inhibition of cell proliferation and the facilitation of apoptosis in HTR8/SVneo cells. Our findings suggest that KCNQ1OT1 may exert a regulatory influence on SOCS3 through a competitive binding mechanism with miR-29a-3p. Notably, KCNQ1OT1 exhibited expression in both the cytoplasm and nucleus, with a predominant localization in the cytoplasm. Furthermore, we observed a negative regulatory relationship between miR-29a-3p and SOCS3, as the miR-29a-3p mimic group demonstrated significantly reduced cell proliferation and an increased rate of apoptosis when compared to the negative control (NC mimic) group. Additionally, the SOCS3 Vector group exhibited a substantial improvement in proliferation capability and a marked reduction in the apoptosis rate in comparison to the NC Vector group. The miR-29a-3p mimic + SOCS3 Vector group demonstrated a remarkable enhancement in proliferation and a reduction in apoptosis when compared to the miR-29a-3p mimic group. CONCLUSION: The competitive binding of miR-29a-3p to LncRNA-KCNQ1OT1 appears to result in the elevation of SOCS3 expression, consequently fostering the proliferation of trophoblast cells while concomitantly suppressing apoptosis.

SOCS3 regulates pathological retinal angiogenesis through modulating SPP1 expression in microglia and macrophages.

Pathological ocular angiogenesis has long been associated with myeloid cell activation. However, the precise cellular and molecular mechanisms governing the intricate crosstalk between the immune system and vascular changes during ocular neovascularization formation remain elusive. In this study, we demonstrated that the absence of the suppressor of cytokine signaling 3 (SOCS3) in myeloid cells led to a substantial accumulation of microglia and macrophage subsets during the neovascularization process. Our single-cell RNA sequencing data analysis revealed a remarkable increase in the expression of the secreted phosphoprotein 1 (Spp1) gene within these microglia and macrophages, identifying subsets of Spp1-expressing microglia and macrophages during neovascularization formation in angiogenesis mouse models. Notably, the number of Spp1-expressing microglia and macrophages exhibited further elevation during neovascularization in mice lacking myeloid SOCS3. Moreover, our investigation unveiled the Spp1 gene as a direct transcriptional target gene of signal transducer and activator of transcription 3. Importantly, pharmaceutical activation of SOCS3 or blocking of SPP1 resulted in a significant reduction in pathological neovascularization. In conclusion, our study highlights the pivotal role of the SOCS3/STAT3/SPP1 axis in the regulation of pathological retinal angiogenesis.

Marine sponge-derived alkaloid ameliorates DSS-induced IBD via inhibiting IL-6 expression through modulating JAK2-STAT3-SOCS3 pathway.

Cyanogramide (AC14), a novel alkaloid, isolated from the fermentation broth of the marine-derived Actinoalloteichus cyanogriseus. However, the exact role of AC14 in inflammatory bowel disease (IBD) is poorly understood. Our results demonstrated that AC14 exhibited significant inhibition of IL-6 release in THP-1 cells and a "Caco-2/THP-1" coculture system after stimulation with LPS for 24 h. However, no significant effect on TNF-α production was observed. Furthermore, in 2.5 % DSS-induced colitis mice, AC14 treatment led to improvement in body weight, colon length, and intestine mucosal barrier integrity. AC14 also suppressed serum IL-6 production and modulated dysregulated microbiota in the mice. Mechanistically, AC14 was found to inhibit the phosphorylation of Janus kinase (JAK) 2 and signal transducers and activators of transcription (STAT) 3, while simultaneously elevating the expression of suppressor of cytokine signaling (SOCS) 3, both in vivo and in vitro. These findings suggest that AC14 exerts its suppressive effects on IL-6 production in DSS-induced IBD mice through the JAK2-STAT3-SOCS3 signaling pathway. Our study highlights the potential of AC14 as a therapeutic agent for the treatment of IBD.

Suppression of SOCS3 expression in macrophage cells: Potential application in diabetic wound healing.

Impaired polarization of M1 to M2 macrophages has been reported in diabetic wounds. We aimed to improve this polarization by down-regulation of expression of the "Suppressor of Cytokine Signaling 3" (SOCS3) gene in macrophages. Two oligodeoxynucleotide (ASO) sequences were designed against SOC3 mRNA and were loaded to mannosylated-polyethyleneimine (Man-PEI). The optimum N/P ratio for Man-PEI-ASO was determined to be 8 based on loading efficiency, particle size, zeta potential, cellular uptake and cytotoxicity assay. pH stability of ASO in Man-PEI-ASO and its protection from DNase I was confirmed. After in vitro treatment of macrophages with Man-PEI-ASO, SOCS3 was downregulated, SOCS1 upregulated, and SOCS1/SOCS3 ratio increased. Also, expressions of macrophage markers of M2 (IL-10, Arg1, CD206) increased and those of M1 (IL-1ß, NOS2, CD68) decreased, and secretion of pro-inflammatory cytokines (TNF-α and IL-1ß) decreased while that of anti-inflammatory cytokine IL-4 increased. All suggested a polarization into M2 phenotype. Finally, the Man-PEI-ASO was loaded in hydrogel and applied to a diabetic wound model in mice. It improved the healing to the level observed in non-diabetic wounds. We show that using antisense sequences against SOC3 mRNA, macrophage polarization could be directed into the M2 phenotype and healing of diabetic wound could be highly improved.

Bushenhuoluo Decoction improves polycystic ovary syndrome by regulating exosomal miR-30a-5p/ SOCS3/mTOR/NLRP3 signaling-mediated autophagy and pyroptosis.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a frequent and complicated endocrine disease that remains a major reason for infertility. Bushenhuoluo Decotion (BSHLD) has been validated to exhibit curative effects on PCOS. This study was aimed to explore the potential mechanism underlying the therapeutic action of BSHLD. METHODS: PCOS rat model was induced by dehydroepiandrosterone (DHEA). Serum hormone and cytokines levels and ovarian pathological alterations were measured to assess ovarian function. Exosomes (Exos) were identified by Transmission electron microscopy and Nanoparticle Tracking Analysis. RT-qPCR, Western blotting, immunohistochemical staining, and immunofluorescence staining were performed to detect molecule expressions. Proliferation and pyroptosis of granulosa cells (GCs) were evaluated by CCK-8 and flow cytometry, respectively. The binding relationship between miR-30a-5p and suppressor of cytokine signaling 3 (SOCS3) was verified by dual luciferase reporter and RIP assays. RESULTS: BSHLD treatment improved serum hormone abnormality, insulin sensitivity, and ovarian morphologic changes of PCOS rats. Moreover, BSHLD treatment restrained the excessive autophagy and pyroptosis in ovarian tissues of PCOS rats. Moreover, BSHLD reduced the expression of miR-30a-5p in serum, serum-derived Exos, and ovarian tissues, thus inhibiting autophagy and NLRP3-mediated pyroptosis in GCs. Mechanistically, SOCS3 was proved as a target of miR-30a-5p and could activate mTOR/P70S6K pathway to repress autophagy. The inhibitory effect of miR-30a-5p deficiency on autophagy and pyroptosis of GCs was attenuated by rapamycin. CONCLUSION: Collectively, BSHLD suppressed autophagy and pyroptosis to improve POCS by regulating exosomal miR-30a-5p/SOCS3/mTOR signaling.

Neuropathic pain development following nerve injury is mediated by SOX11-ARID1A-SOCS3 transcriptional regulation in the spinal cord.

BACKGROUND: Neuropathic pain, a complex condition originating from nervous system damage, remains a significant clinical challenge due to limited understanding of its underlying mechanisms. Recent research highlights the SOX11 transcription factor, known for its role in nervous system development, as a crucial player in neuropathic pain development and maintenance. This study investigates the role of the SOX11-ARID1A-SOCS3 pathway in neuropathic pain modulation within the spinal cord. METHODS AND RESULTS: Using a spinal nerve ligation (SNL) model in mice, we observed a significant upregulation of Sox11 in the spinal cord dorsal horn post-injury. Intrathecal administration of Sox11 shRNA mitigated SNL-induced neuropathic pain behaviors, including mechanical allodynia and heat hyperalgesia. Further, we demonstrated that Sox11 regulates neuropathic pain via transcriptional control of ARID1A, with subsequent modulation of SOCS3 expression. Knockdown of ARID1A and SOCS3 via shRNA resulted in alleviation of Sox11-induced pain sensitization. Additionally, Sox11 overexpression led to an increase in ARID1A binding to the SOCS3 promoter, enhancing chromatin accessibility and indicating a direct regulatory relationship. These findings were further supported by in vitro luciferase reporter assays and chromatin accessibility analysis. CONCLUSIONS: The SOX11-ARID1A-SOCS3 pathway plays a pivotal role in the development and maintenance of neuropathic pain. Sox11 acts as a master regulator, modulating ARID1A, which in turn influences SOCS3 expression, thereby contributing to the modulation of neuropathic pain. These findings provide a deeper understanding of the molecular mechanisms underlying neuropathic pain and highlight potential therapeutic targets for its treatment. The differential regulation of this pathway in the spinal cord and dorsal root ganglia (DRG) underscores its complexity and the need for targeted therapeutic strategies.

Regulation of SOCS3-STAT3 in urate-induced cytokine production in human myeloid cells.

OBJECTIVE: Hyperuricaemia is necessary for gout. High urate concentrations have been linked to inflammation in mononuclear cells. Here, we explore the role of the suppressor of cytokine signaling 3 (SOCS3) in urate-induced inflammation. METHODS: Peripheral blood mononuclear cells (PBMCs) from gout patients, hyperuricemic and normouricemic individuals were cultured for 24h with varying concentrations of soluble urate, followed by 24h restimulation with lipopolysaccharides (LPS)±monosodium urate (MSU) crystals. Transcriptomic profiling was performed using RNA-Sequencing. DNA methylation was assessed using Illumina Infinium® MethylationEPIC BeadChip system (EPIC array). Phosphorylation of signal transducer and activator of transcription 3 (STAT3) was determined by flow cytometry. Cytokine responses were also assessed in PBMCs from patients with JAK2 V617F tyrosine kinase mutation. RESULTS: PBMCs pre-treated with urate produced more interleukin-1beta (IL-1ß) and interleukin-6 (IL-6) and less interleukin-1 receptor anatagonist (IL-1Ra) after LPS simulation. In vitro, urate treatment enhanced SOCS3 expression in control monocytes but no DNA methylation changes were observed at the SOCS3 gene. A dose-dependent reduction in phosphorylated STAT3 concomitant with a decrease in IL-1Ra was observed with increasing concentrations of urate. PBMCs with constitutively activated STAT3 (JAK2 V617F mutation) could not be primed by urate. CONCLUSION: In vitro, urate exposure increased SOCS3 expression, while urate priming, and subsequent stimulation resulted in decreased STAT3 phosphorylation and IL-1Ra production. There was no evidence that DNA methylation constitutes a regulatory mechanism of SOCS3. Elevated SOCS3 and reduced pSTAT3 could play a role in urate-induced hyperinflammation since urate priming had no effect in PBMCs from patients with constitutively activated STAT3.

Tumor Cell-Derived Exosomal miR-191-5p Activates M2-Subtype Macrophages Through SOCS3 to Facilitate Breast Cancer.

Differential activation of macrophages is associated with poor progression of breast cancer (BC). Many reports have elucidated the important involvement of exosomes produced by cancer cells in remodeling the macrophage activation phenotype to promote tumor expansion and invasion. However, the underlying mechanisms by which exosomes secreted by BC cells facilitate macrophage M2 polarization remain enigmatic and worth exploring. In this study, quantitative real-time PCR (RT-qPCR) was used to investigate miR-191-5p expression in BC tumor tissues and cells. Cell counting kit 8 (CCK-8), transwell, and flow cytometry were applied to assess the functional role of miR-191-5p in BC. Isolated nano-vesicles were identified using transmission electron microscopy and western blotting. We also observed that miR-191-5p was significantly elevated in BC clinical samples and that inhibition of miR-191-5p hindered the growth and metastasis of BC cells. Importantly, BC cells successfully accelerated macrophage M2-like polarization by directly transferring exosomes to macrophages, resulting in increased miR-191-5p levels in macrophages. Mechanistically, exosomal miR-191-5p directly inhibited the suppressors of cytokine signaling 3 (SOCS3) expression in macrophages and aggravated macrophage M2 polarization. Similarly, si-SOCS3 transfected macrophages boosted BC cell migration and invasion in a positive feedback manner. Overall, our results manifested a pro-growth and pro-metastatic role between the two cells by elucidating the crucial role of exosomal miR-191-5p in stimulating M2 macrophage polarization and mediating communication between BC cells and macrophages. These findings opened up new horizons for the development of BC therapeutic strategies.

SOCS3, Transcriptionally Activated by NR4A1, Induces Apoptosis and Extracellular Matrix Degradation of Vaginal Fibroblasts in Pelvic Organ Prolapse

Background: Pelvic organ prolapse (POP) is a common gynecological chronic disorder. Human vaginal fibroblasts (HVFs) that maintain the integrity of vaginal wall tissues are essential for keeping pelvic organs in place. Apoptosis and the degradation of the extracellular matrix in HVFs contribute to the progression of POP. The cytokine signal transduction inhibitor 3 (SOCS3) exerts significant regulatory effects on cell signal transduction pathways, thereby affecting various pathological processes. Aims: To explore the role and mechanism of SOCS3 on HVFs in the context of POP. Study Design: In vitro cell lines and human-sample study. Methods: Anterior vaginal wall tissues were obtained from POP or non-POP patients for the analysis of SOCS3 expression. HVFs were isolated from the vaginal tissues of POP patients, and SOCS3 was either overexpressed or knocked down in HVFs via lentivirus infection. Subsequently, the biological function and mechanism of SOCS3 in HVFs were investigated. Results: SOCS3 was highly expressed in the vaginal tissues of POP patients compared to non-POP patients. Functionally, the overexpression of SOCS3 suppressed cell viability while promoting cell apoptosis in HVFs. The overexpression of SOCS3 also accelerated extracellular matrix degradation (decreasing collagen I, collagen III, and elastin, and increasing MMP2 and MMP9). In terms of mechanism, NR4A1 transcriptionally activated SOCS3 by binding to its promoter. Furthermore, rescue experiments revealed that SOCS3 knockdown hindered NR4A1 overexpression-induced cell apoptosis and extracellular matrix degradation in HVFs. Conclusion: SOCS3 mediated the apoptotic and extracellular matrix degradation effects of NR4A1 on HVFs, underlining that the restraining of the SOCS3 expression may be a promising strategy for POP treatment.

DNMTs-mediated SOCS3 methylation promotes the occurrence and development of AML.

OBJECTIVES: As a tumor suppressor gene, SOCS3 inhibits the growth of tumor cells by regulating JAK/STAT signaling pathway through negative feedback. This study aimed to investigate the biological function and mechanism of SOCS3 methylation mediated by DNMTs in the development of AML. METHODS: Bone marrow samples were collected from 70 AML patients and 20 healthy volunteers. The expression and methylation status of each gene were detected by RT-qPCR, western blot and MS-PCR, and the growth and apoptosis rate of leukemia cell lines were detected by CCK-8 and flow cytometry. The effects of changes in SOCS3 gene expression and methylation status of AML cell lines were observed by gene transfection and gene knockdown. RESULTS: The methylation rate of SOCS3 in AML initial treatment group was significantly higher than that in the remission group and the normal control group (60% vs. 0%, 0%). The expression of SOCS3 in the SOCS3 methylation group was significantly lower than that in the non-methylated group and control group, while the expression of DNMT1, DNMT3a, p-JAK2, p-STAT3 and p-STAT5 were significantly higher than those in the non-methylated group and control group. Demethylation treatment, SOCS3 transfection and DNMT3a knockdown could up-regulate the expression of SOCS3, which decreased the proliferation and increased the apoptosis of leukemia cell lines. CONCLUSION: SOCS3 methylation mediated by DNMTs promotes the occurrence and development of AML and can be used as a potential biomarker for the diagnosis and efficacy evaluation of AML.

Silencing suppressor of cytokine signaling 3 induces apoptosis and activates the p-STAT3/NF-κB pathway in hypoxic cultivated H9c2 cells.

Suppressor of cytokine signaling 3 (SOCS3) plays a significant role in the process of myocardial adaptation to chronic hypoxia. SOCS3 finely regulates cell signaling cross-talk that occurs between NF-κB and STAT3 during the compensatory protective response. However, the role and mechanism of SOCS3 in hypoxic cardiomyocytes are not fully understood. In the study, we investigated the effect of SOCS3 on the p65 and STAT3 signaling pathways and further examined the potential molecular mechanism involved in regulating apoptosis. Our data showed that SOCS3 silencing could upregulate Ac-p65, p-p65, and p-STAT3 expression in nuclear extracts of H9c2 cells that received hypoxic treatment for 24, 48, and 72 h. SOCS3 silencing also remarkably increased the DNA-binding activity of the p65 motif in hypoxic cultivated H9c2 cells. We also found that SOCS3 knockdown increased cleaved-caspase-3, Bax, and PUMA expression and decreased cleaved PARP and Bcl-2 in expression in hypoxic H9c2 cells. Silencing of SOCS3 caused an increase in LDH leakage from injured cardiomyocytes and reduced cell viability under conditions of hypoxic stress. Furthermore, SOCS3 silencing enhanced the apoptosis of H9c2 cells at 72 h of hypoxia. These findings suggest that knockdown of SOCS3 leads to excessive activation of the NF-κB pathway, which, in turn, might promote apoptosis under conditions of chronic hypoxia.

METTL3 facilitates stemness properties and tumorigenicity of cancer stem cells in hepatocellular carcinoma through the SOCS3/JAK2/STAT3 signaling pathway.

Liver cancer stem cells (LCSCs) contribute to tumor recurrence and cancer cell proliferation in patients with hepatocellular carcinoma (HCC). METTL3-catalyzed m6A modification is relevant to the cancer stem cell (CSC) phenotype, including LCSCs. LCSCs were isolated from MHCC-97H and HepG2 cells through flow cytometry. UALCAN data were used to analyze the expression of METTL3 in liver hepatocellular carcinoma (LIHC) tissues. Loss- and gain-of-function experiments were utilized to assess the biological effects of METTL3 and SOCS3 on the proliferation and stemness phenotypes in vitro and in vivo. The mechanisms underlying the impact of METTL3 were explored using qPCR, MeRIP-qPCR, dual-luciferase reporter, and western blot assays. METTL3 was significantly upregulated in LIHC tissues according to the UALCAN database. METTL3 was highly expressed in LIHC and was significantly correlated with individual cancer stage, tumor grade and lymph node metastasis. Patients with low METTL3 expression had a longer overall survival time based on the data from UALCAN. In addition, the level of METTL3 was enhanced in LCSCs and decreased in non-LCSCs compared to HCC cells. Moreover, overexpression of METTL3 stimulated the proliferation and stemness of LCSCs in vitro and in vivo, while loss of METTL3 impeded it. Bioinformatics analysis combined with validation experiments determined that m6A was modified by METTL3-targeting SOCS3 mRNA. METTL3 had side effects regarding the stability of SOCS3 mRNA. SOCS3 overexpression impaired and SOCS3 depletion facilitated the development of LCSCs via the JAK2/STAT3 pathway. Furthermore, METTL3 depletion suppressed proliferation and stemness in LCSCs, which was restored by SOCS3 knockdown or colivelin treatment. We discovered that METTL3 facilitated the stemness and tumorigenicity of LCSCs by modifying SOCS3 mRNA with m6A.

Transcriptional regulation of suppressors of cytokine signaling during infection with Mycobacterium tuberculosis in human THP-1-derived macrophages and in mice.

Mycobacterium tuberculosis (Mtb) infection leads to upregulation of Suppressors of Cytokine signaling (SOCS) expression in host macrophages (Mϕ). SOCS proteins inhibit cytokine signaling by negatively regulating JAK/STAT. We investigated this host-pathogen dialectic at the level of transcription. We used phorbol-differentiated THP-1 Mϕ infected with Mtb to investigate preferential upregulation of some SOCS isoforms that are known to inhibit signaling by IFN-γ, IL-12, and IL-6. We examined time kinetics of likely transcription factors and signaling molecules upstream of SOCS transcription, and survival of intracellular Mtb following SOCS upregulation. Our results suggest a plausible mechanism that involves PGE2 secretion during infection to induce the PKA/CREB axis, culminating in nuclear translocation of C/EBPß to induce expression of SOCS1. Mtb-infected Mϕ secreted IL-10, suggesting a mechanism of induction of STAT3, which may subsequently induce SOCS3. We provide evidence of temporal variation in SOCS isoform exspression and decay. Small-interfering RNA-mediated knockdown of SOCS1 and SOCS3 restored the pro-inflammatory milieu and reduced Mtb viability. In mice infected with Mtb, SOCS isoforms persisted across Days 28-85 post infection. Our results suggest that differential temporal regulation of SOCS isoforms by Mtb drives the host immune response towards a phenotype that facilitates the pathogen's survival.

Polysaccharides from Dendrobium officinale improve obesity-induced insulin resistance through the gut microbiota and the SOCS3-mediated insulin receptor substrate-1 signaling pathway.

BACKGROUND: Obesity induces insulin resistance and chronic inflammation, impacting human health. The relationship between obesity, gut microbiota, and regulatory mechanisms has been studied extensively. Dendrobium officinale polysaccharide (DOP), a traditional Chinese herbal medicine, potentially reduces insulin resistance. However, the mechanism through which DOP affects gut microbiota and alleviates obesity-induced insulin resistance in rats requires further investigation. RESULTS: The current study aimed to assess the impact of DOP on gut microbiota and insulin resistance in rats on a high-fat diet. The results revealed that DOP effectively reduced blood lipids, glucose disorders, oxidative stress, and inflammatory infiltration in the liver of obese Sprague Dawley rats. This was achieved by downregulating SOCS3 expression and upregulating insulin receptor substrate-1 (IRS-1) by regulating the JAK/STAT/SOCS3 signaling pathway. Notably, DOP intervention enhanced the abundance of beneficial gut microbiota and reduced harmful microbiota. Correlation analysis demonstrated significant associations among intestinal microbiota, SOCS3-mediated IRS-1 expression, and inflammatory factors. CONCLUSION: Dendrobium officinale polysaccharide regulated the gut microbiota, enhanced IRS-1 expression, and mitigated liver injury and insulin resistance due to a high-fat diet. These findings depict the potential anti-insulin resistance properties of DOP and offer further evidence for addressing obesity and its complications. © 2023 Society of Chemical Industry.

MiR-9 promotes G-MDSC recruitment and tumor proliferation by targeting SOCS3 in breast cancer.

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of cells that differentiate from myeloid cells, proliferate in cancer and inflammatory reactions, and mainly exert immunosuppressive functions. Nonetheless, the precise mechanisms that dictate both the accumulation and function of MDSCs remain only partially elucidated. In the course of our investigation, we observed a positive correlation between the content of MDSCs especially G-MDSCs and miR-9 level in the tumor tissues derived from miR-9 knockout MMTV-PyMT mice and 4T1 tumor-bearing mice with miR-9 overexpression. Combined with RNA-seq analysis, we identified SOCS2 and SOCS3 as direct targets of miR-9. Additionally, our research unveiled the pivotal role of the CCL5/CCR5 axis in orchestrating the chemotactic recruitment of G-MDSCs within the tumor microenvironment, a process that is enhanced by miR-9. These findings provide fresh insights into the molecular mechanisms governing the accumulation of MDSCs within the framework of breast cancer development.

SOCS3 inhibiting JAK-STAT pathway enhances oncolytic adenovirus efficacy by potentiating viral replication and T-cell activation.

Oncolytic viruses (OVs) are emerging as a potentially useful treatment for malignancies due to the capabilities of direct oncolysis and immune induction. Improving the replication of OVs is an effective approach to enhance the oncolytic effects. Here, we observed that cancer cells with deficiencies in JAK-STAT pathway showed greater sensitivity to oncolytic adenovirus (oAd), and JAK inhibitor could enhance the replication of oAd. Therefore, we constructed a novel oAd expressing SOCS3, a major negative regulator of JAK-STAT pathway, and confirmed that oAd-SOCS3 exhibited a more significant antitumor effect than oAd-Ctrl both in vitro and in vivo. Mechanistically, SOCS3 inhibited the activation of JAK-STAT pathway, resulting in stronger tumor selective replication of oAd and downregulated expression of PD-L1 on cancer cells as well. Both benefits could collectively awaken antitumor immunity. This study highlights the importance of JAK-STAT pathway in viral replication and confirms the treatment of oAd-SOCS3 in potential clinical applications.

Ozone alleviates MSU-induced acute gout pain via upregulating AMPK/GAS6/MerTK/SOCS3 signaling pathway.

BACKGROUND: Gout pain seriously affects the quality of patients' life. There is still no effective treatment. The inflammatory response is the main mechanism of gout. Here, we found that ozone can reduce the inflammatory reaction in the joints of gouty mice and relieve gout pain, and we further explore its protective mechanism. METHODS: MSU was used to establish the gouty mice model. Nociception was assessed by Von Frey hairs. Cell signaling assays were performed by western blotting and immunohistochemistry. The mouse leukemia cells of monocyte macrophage line RAW264.7 were cultured to investigate the effects of ozone administration on macrophage. RESULTS: Ozone reduced inflammation, relieved gout pain and improved the paw mean intensity and duty cycle of the gouty mice. Ozone increased the phosphorylation of AMP-activated protein kinase (AMPK), induced suppressor of cytokine signaling 3 (SOCS3) expression and inhibited metallopeptidase 9 (MMP9) expression. In vivo, ozone activated AMPK to induce Gas6 release, and upregulated MerTK/SOCS3 signaling pathway to reduce inflammation in mouse macrophage line RAW264.7. Inhibitors of AMPK and MerTK, respectively abolished the analgesic and anti-inflammatory effects of ozone in vivo and in vitro. Gas6 knockout cancelled the protectively effects of ozone on gout pain and the paw mean intensity and duty cycle of gouty mice. Additionally, the level of Gas6 and protein S in plasma of patients with hyperuricemia was significantly higher than that of healthy contrast group. CONCLUSION: Ozone reduces inflammation and alleviates gout pain by activating AMPK to up-regulate Gas6/MerTK/SOCS3 signaling pathway.