L-arginine attenuates Streptococcus uberis-induced inflammation by decreasing miR155 level.

L-arginine, as an essential substance of the immune system, plays a vital role in innate immunity. MiR155, a multi-functional microRNA, has gained importance as a regulator of homeostasis in immune cells. However, the immunoregulatory mechanism between L-arginine and miR155 in bacterial infections is unknown. Here, we investigated the potential role of miR155 in inflammation and the molecular regulatory mechanisms of L-arginine in Streptococcus uberis (S. uberis) infections. And we observed that miR155 was up-regulated after infection, accompanying the depletion of L-arginine, leading to metabolic disorders of amino acids and severe tissue damage. Mechanically, the upregulated miR155 mediated by the p65 protein played a pro-inflammatory role by suppressing the suppressor of cytokine signaling 6 (SOCS6)-mediated p65 ubiquitination and degradation. This culminated in a violently inflammatory response and tissue damage. Interestingly, a significant anti-inflammatory effect was revealed in L-arginine supplementation by reducing miR155 production via inhibiting p65. This work firstly uncovers the pro-inflammatory role of miR155 and an anti-inflammatory mechanism of L-arginine in S.uberis infection with a mouse mastitis model. Collectively, we provide new insights and strategies for the prevention and control of this important pathogen, which is of great significance for ensuring human food health and safety.

Analysis of epigenetic clocks links yoga, sleep, education, reduced meat intake, coffee, and a SOCS2 gene variant to slower epigenetic aging.

DNA methylation (DNAm) clocks hold promise for measuring biological age, useful for guiding clinical interventions and forensic identification. This study compared the commonly used DNAm clocks, using DNA methylation and SNP data generated from nearly 1000 human blood or buccal swab samples. We evaluated different preprocessing methods for age estimation, investigated the association of epigenetic age acceleration (EAA) with various lifestyle and sociodemographic factors, and undertook a series of novel genome-wide association analyses for different EAA measures to find associated genetic variants. Our results highlighted the Skin&Blood clock with ssNoob normalization as the most accurate predictor of chronological age. We provided novel evidence for an association between the practice of yoga and a reduction in the pace of aging (DunedinPACE). Increased sleep and physical activity were associated with lower mortality risk score (MRS) in our dataset. University degree, vegetable consumption, and coffee intake were associated with reduced levels of epigenetic aging, whereas smoking, higher BMI, meat consumption, and manual occupation correlated well with faster epigenetic aging, with FitAge, GrimAge, and DunedinPACE clocks showing the most robust associations. In addition, we found a novel association signal for SOCS2 rs73218878 (p = 2.87 × 10-8) and accelerated GrimAge. Our study emphasizes the importance of an optimized DNAm analysis workflow for accurate estimation of epigenetic age, which may influence downstream analyses. The results support the influence of genetic background on EAA. The associated SOCS2 is a member of the suppressor of cytokine signaling family known for its role in human longevity. The reported association between various risk factors and EAA has practical implications for the development of health programs to improve quality of life and reduce premature mortality associated with age-related diseases.

Hypothalamic FTO promotes high-fat diet-induced leptin resistance in mice through increasing CX3CL1 expression.

Long-term consumption of a high-fat diet (HFD) disrupts energy homeostasis and leads to weight gain. The fat mass and obesity-associated (FTO) gene has been consistently identified to be associated with HFD-induced obesity. The hypothalamus is crucial for regulating energy balance, and HFD-induced hypothalamic leptin resistance contributes to obesity. FTO, an N6-methyladenosine (m6A) RNA methylation regulator, may be a key mediator of leptin resistance. However, the exact mechanisms remain unclear. Therefore, the present study aims to investigate the association between FTO and leptin resistance. After HFD or standard diet (SD) feeding in male mice for 22 weeks, m6A-sequencing and western blotting assays were used to identify target genes and assess protein level, and molecular interaction changes. CRISPR/Cas9 gene knockout system was employed to investigate the potential function of FTO in leptin resistance and obesity. Our data showed that chemokine (C-X3-C motif) ligand 1 (CX3CL1) was a direct downstream target of FTO-mediated m6A modification. Furthermore, upregulation of FTO/CX3CL1 and suppressor of cytokine signaling 3 (SOCS3) in the hypothalamus impaired leptin-signal transducer and activator of transcription 3 signaling, resulting in leptin resistance and obesity. Compared to wild-type (WT) mice, FTO deficiency in leptin receptor-expressing neurons of the hypothalamus significantly inhibited the upregulation of CX3CL1 and SOCS3, and partially ameliorating leptin resistance under HFD conditions. Our findings reveal that FTO involved in the hypothalamic leptin resistance and provides novel insight into the function of FTO in the contribution to hypothalamic leptin resistance and obesity.

Effects of antidiabetics and exercise therapy on suppressors of cytokine signaling-1, suppressors of cytokine signaling-3, and insulin receptor substrate-1 molecules in diabetes and obesity.

OBJECTIVE: Pathological destruction of insulin signaling molecules such as insulin receptor substrate, especially due to the increase in suppressors of cytokine signaling molecules, has been demonstrated in experimental diabetes. The contribution of suppressors of cytokine signaling proteins to the development of insulin resistance and the effects of antidiabetic drugs and exercise on suppressors of cytokine signaling proteins are not clearly known. METHODS: A total of 48 Wistar albino adult male rats were divided into six groups: control group, obese group with diabetes, obese diabetic rats treated with metformin, obese diabetic rats treated with pioglitazone, obese diabetic rats treated with exenatide, and obese diabetic rats with applied exercise program. Immunohistochemical staining was performed in both the liver and adipose tissue. RESULTS: There was a statistically significant decrease in suppressors of cytokine signaling-1, a decrease in suppressors of cytokine signaling-3, an increase in insulin receptor substrate-1, and a decrease in immunohistochemical staining in the obese group treated with metformin and exenatide compared to the obese group without treatment in the liver tissue (p<0.05). A statistically significant decrease in immunohistochemical staining of suppressors of cytokine signaling-1 and suppressors of cytokine signaling-3 was found in the obese group receiving exercise therapy compared to the obese group without treatment in visceral adipose tissue (p<0.05). Likewise, no significant immunohistochemistry staining was seen in diabetic obese groups. CONCLUSION: Metformin or exenatide treatment could prevent the degradation of insulin receptor substrate-1 protein by reducing the effect of suppressors of cytokine signaling-1 and suppressors of cytokine signaling-3 proteins, especially in the liver tissue. In addition, exercise can play a role as a complementary therapy by reducing suppressors of cytokine signaling-1 and suppressors of cytokine signaling-3 proteins in visceral adipose tissue.

Xuanfei Baidu Decoction suppresses complement overactivation and ameliorates IgG immune complex-induced acute lung injury by inhibiting JAK2/STAT3/SOCS3 and NF-κB signaling pathway.

BACKGROUND: The significant clinical efficacy of Xuanfei Baidu Decoction (XFBD) is proven in the treatment of patients with coronavirus disease 2019 (COVID-19) in China. However, the mechanisms of XFBD against acute lung injury (ALI) are still poorly understood. METHODS: In vivo, the mouse model of ALI was induced by IgG immune complexes (IgG-IC), and then XFBD (4g/kg, 8g/kg) were administered by gavage respectively. 24 h after inducing ALI, the lungs were collected for histological and molecular analysis. In vitro, alveolar macrophages inflammation models induced by IgG-IC were performed and treated with different dosage of XFBD-containing serum to investigate the protective role and molecular mechanisms of XFBD. RESULTS: The results revealed that XFBD mitigated lung injury and significantly downregulated the production of pro-inflammatory mediators in lung tissues and macrophages upon IgG-IC stimulation. Notably, XFBD attenuated C3a and C5a generation, inhibited the expression of C3aR and C5aR and suppressed the activation of JAK2/STAT3/SOCS3 and NF-κB signaling pathway in lung tissues and macrophages induced by IgG-IC. Moreover, in vitro experiments, we verified that Colivelin TFA (CAF, STAT3 activator) and C5a treatment markedly elevated the IgG-IC-triggered inflammatory responses in macrophages and XFBD weakened the effects of CAF or C5a. CONCLUSION: XFBD suppressed complement overactivation and ameliorated IgG immune complex-induced acute lung injury by inhibiting JAK2/STAT3/SOCS3 and NF-κB signaling pathway. These data contribute to understanding the mechanisms of XFBD in COVID-19 treatment.

Regional specific effect of saturated vs unsaturated fat on leptin receptor signalling in mice brain areas regulating feeding.

Leptin receptors (LepR) are expressed in brain areas controlling food intake homeostasis, such as the hypothalamus, the hippocampus and the prefrontal cortex. In a previous study we reported that long-term intake of saturated and monounsaturated fat alters hypothalamic LepR signalling. The current study aims at investigating the effect of foods high in either saturated (SOLF) or monounsaturated fat (UOLF) on LepR functionality in the hippocampus and the prefrontal cortex. Male mice were placed on SOLF/UOLF (eight weeks), then treated with recombinant murine leptin (1 mg/kg). After 60 min, brain regions were dissected and processed for western blot of phosphorylated STAT3 (pSTAT3), Akt (pAkt) and AMPK (pAMPK). Levels of SOCS3 were also quantified. SOLF itself increased basal levels of pSTAT3, while UOLF impaired leptin-induced phosphorylation of both Akt and AMPK. SOCS3 levels were specifically increased by UOLF within the prefrontal cortex. Our results show that SOLF and UOLF differently affect LepR signalling within the hippocampus and the prefrontal cortex, which points to the complex effect of saturated and unsaturated fat on brain function, particularly in areas regulating food intake.

Downregulation of the GHRH/GH/IGF1 axis in a mouse model of Börjeson-Forssman-Lehman syndrome.

Börjeson-Forssman-Lehmann syndrome (BFLS) is an intellectual disability and endocrine disorder caused by plant homeodomain finger 6 (PHF6) mutations. Individuals with BFLS present with short stature. We report a mouse model of BFLS, in which deletion of Phf6 causes a proportional reduction in body size compared with control mice. Growth hormone (GH) levels were reduced in the absence of PHF6. Phf6-/Y animals displayed a reduction in the expression of the genes encoding GH-releasing hormone (GHRH) in the brain, GH in the pituitary gland and insulin-like growth factor 1 (IGF1) in the liver. Phf6 deletion specifically in the nervous system caused a proportional growth defect, indicating a neuroendocrine contribution to the phenotype. Loss of suppressor of cytokine signaling 2 (SOCS2), a negative regulator of growth hormone signaling partially rescued body size, supporting a reversible deficiency in GH signaling. These results demonstrate that PHF6 regulates the GHRH/GH/IGF1 axis.

Ling-gui-zhu-gan decoction alleviates hepatic steatosis through SOCS2 modification by N6-methyladenosine.

BACKGROUND: The ling-gui-zhu-gan (LGZG) decoction is a classic formula in traditional chinese medicine (TCM) and is widely used in clinical settings. Recently, the LGZG decoction was demonstrated to have an effect in alleviating hepatic steatosis induced by a high-fat diet (HFD). However, the mechanisms underlying this therapeutic effect remain unclear. The present study was designed to evaluate the effect and explore possible mechanisms of action of the LGZG decoction in nonalcoholic fatty liver disease (NAFLD). METHODS: Liver tissue and blood samples were harvested. Liver steatosis, triglyceride (TG), liver total cholesterol (TC), liver low-density lipoprotein (LDL), serum almandine aminotransferase (ALT), aspartate aminotransferase (AST), and free fatty acid (FFA) were assayed. N6-methyladenosine (m6A) levels were estimated using an m6A RNA methylation quantification kit and immunohistochemistry. The m6A methylome was detected through methylated RNA immunoprecipitation sequencing (MeRIP-seq), followed by data analysis. The expression levels of differentially methylated genes (DMGs) were determined using real-time polymerase chain reaction and western blotting. RESULTS: The LGZG decoction significantly alleviated hepatic steatosis and reduced m6A levels. MeRIP-seq revealed the coding sequence (CDS) domain to be the most critical modification site for m6A methylation, and the molecular functions of DMGs predominantly included insulin-like growth factor receptor binding and fatty acid metabolism and degradation. Further, LGZG treatment could reduce the m6A methylation levels of suppressor of cytokine signaling 2 (SOCS2), along with the expression of SOCS2 at mRNA and protein levels. CONCLUSIONS: The LGZG decoction is an effective formula for treating NAFLD, and the possible mechanisms underlying its action could be related to N6-methyladenosine modification-medicated SOCS2.

Pregnancy-induced changes in the transcript levels of prolactin receptor and its suppressor in the ovine hypothalamus and adenohypophysis.

The aim of this study was to analyse changes in the abundance of prolactin (PRL) receptor (PRLR) and suppressor of cytokine signalling-3 (SOCS-3) mRNA in the ventro-/dorsomedial nucleus (VMH/DMH) and arcuate nucleus (ARC) of the hypothalamus as well as in the median eminence (ME) and adenohypophysis (AP) in sheep at 30, 60, 90 and 120 d of pregnancy compared to non-pregnant animals. In the VMH/DMH, PRLR transcripts were detected only in non-pregnant ewes. In the ARC, the abundances of PRLR mRNA were higher in pregnant sheep on days 30 (p < .01), 90 (p < .01) and 120 (p < .05) than in non-pregnant sheep. In contrast, the expression of PRLR mRNA in the ME was lower (p < .01) in pregnant ewes at days 30 and 60 than in non-pregnant ewes and was undetectable at later stages of gestation. In all studied stages of pregnancy except day 60, the abundance of PRLR mRNA was higher (p < .01) in the ARC than in the AP, while in non-pregnant sheep, there were no differences (p ≥ .05) in the transcript levels between these two tissues. In non-pregnant ewes, the abundance of SOCS-3 mRNA in the AP was lower than that in any other studied tissue (p < .05-p < .01). In conclusion, the observed changes in PRLR and SOCS-3 mRNA abundance in the hypothalamus and AP during pregnancy may be important components of the mechanisms regulating the action of PRL in energy homeostasis and neuroendocrine interactions within the hypothalamic-pituitary axis.

HuoXueTongFu Formula Alleviates Intraperitoneal Adhesion by Regulating Macrophage Polarization and the SOCS/JAK2/STAT/PPAR-γ Signalling Pathway.

Intraperitoneal adhesion is a common complication after abdominal surgery, which seriously affects the quality of life of patients. HuoXueTongFu Formula (HXTF) plays an important role in the prevention and treatment of intraperitoneal adhesions. However, the molecular-related mechanisms are still not fully known. In this study, the model of Intrapetitoneal adhesion was established by cecum abrasion and treated with HXTF for one week. RAW264.7 cells were given LPS, IFN-γ, IL-4, HXTF-medicated serum, and PPAR-γ agonist/antagonist, respectively. Histopathology, flow cytometry, ELISA, real-time PCR, and Western blotting were used to further detect the related protein, M1/M2 polarization tendency, and PPAR-γ nuclear translocation. The deposition of collagen fibres reduced in the local area of rats after the operation with HXTF treatment. Similar to IL-4, HXTF induced a tendency for macrophages to polarize toward M2 and promoted peroxisome proliferator-activated receptor-gamma (PPAR-γ) nuclear translocation. Furthermore, the use of HXTF and PPAR-γ agonists downregulated macrophage M1 polarization-related factors IL-1, IL-6, and TNF-alpha and upregulated M2 polarization-related factors IL-4, IL-10, and TGF-beta 1. Meanwhile, the use of HXTF and PPAR-γ agonists downregulated the SOCS3/JAK2/STAT1 pathway and activated the SOCS1/STAT6/PPAR-γ pathway. These results show that HXTF may reduce intraperitoneal adhesion by inducing macrophage M2 polarization and regulating the SOCS/JAK2/STAT/PPAR-γ pathway.

ALA-PDT alleviates the psoriasis by inhibiting JAK signalling pathway.

BACKGROUND: Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is a well-known treatment for non-hypertrophic actinic keratoses and superficial basal-cell carcinomas. OBJECTIVES: In this study, we first revealed that ALA-PDT treatment effectively ameliorated the psoriasis-like lesion in imiquimod (IMQ)-induced mouse model and further explored the potential molecular mechanism and related signalling pathways during the treatment. Besides, we also confirmed a significant alleviation of ALA-PDT therapy on IFN-γ-induced over-proliferation of keratinocytes. METHODS: H&E staining was conducted to reveal the histological changes of mice in different groups. The different expression levels of RNA were illustrated by using QRT-PCR. Western blot was performed to confirm the various expression levels of protein in mice. In vitro, cell proliferation and cell cycle were evaluated by cell counting kit-8 and flow cytometry assay, respectively. RESULTS: The result showed that ALA-PDT's anti-proliferation effect and regulation on Socs1/3, JAK1/2 and K17 in IFN-γ-induced keratinocytes were largely weakened by NAC, indicating that ALA-PDT attenuated the proliferation of IFN-γ-induced keratinocytes by enhancing ROS level. CONCLUSIONS: These results demonstrated that ALA-PDT largely activated the productivity of Socs1/3 in a ROS-dependent manner. Socs1/3 is a potential blocker in JAK signalling pathway and inhibits the proliferation and keratinization of keratinocytes in psoriasis.

miR-1260b, mediated by YY1, activates KIT signaling by targeting SOCS6 to regulate cell proliferation and apoptosis in NSCLC.

Non-small cell lung cancer (NSCLC) is one of the most common aggressive malignancies. miRNAs have been identified as important biomarkers and regulators of NSCLC. However, the functional contributions of miR-1260b to NSCLC cell proliferation and apoptosis have not been studied. In this study, miR-1260b was upregulated in NSCLC plasma, tissues, and cell lines, and its high expression was correlated with tumor size and progression. Functionally, miR-1260b overexpression promoted cell proliferation and cell cycle, conversely inhibited cell apoptosis and senescence. Mechanically, miR-1260b negatively regulated SOCS6 by directly binding to its 3'-UTR. Furthermore, miR-1260b-mediated suppression of SOCS6 activated KIT signaling. Moreover, YY1 was an upstream regulator of miR-1260b. This study is the first to illustrate that miR-1260b, mediated by YY1, activates KIT signaling by targeting SOCS6 to regulate NSCLC cell proliferation and apoptosis, and is a potential biomarker and therapeutic target for NSCLC. In sum, our work provides new insights into the molecular mechanisms of NSCLC involved in cell proliferation and apoptosis.

Effect of osthole on advanced glycation end products-induced renal tubular hypertrophy and role of klotho in its mechanism of action.

BACKGROUND: Osthole has been widely reported to have pharmacological activities such as anti-cancer, anti-inflammation and anti-hyperlipidemic effects. Klotho was identified as an anti-senescence protein in a variety of tissues. Loss of klotho has been associated with chronic kidney disease. However, potential roles and molecular events for osthole and klotho in diabetic nephropathy remain unclear. PURPOSE: In the current study, we undertook to study the effect of osthole on klotho expression in advanced glycation end products (AGE)-cultured human renal proximal tubular cells, and to investigate the molecular mechanisms of osthole and exogenous klotho against AGE-induced renal tubular hypertrophy. METHODS: Cell viability was elucidated by MTT assay. Protein expression was measured by Western blotting. mRNA level was analyzed by real-time PCR. Cellular hypertrophy growth was evaluated by hypertrophy index. Relative cell size was detected by flow cytometry. RESULTS: We found that raising the ambient AGE concentration causes a dose-dependent decrease in klotho synthesis. Osthole significantly increased AGE-inhibited klotho mRNA and protein expression. Osthole and exogenous klotho treatments significantly attenuated AGE-induced Janus kinase 2 (JAK2)-signal transducers and activators of transcription 1 (STAT1) and STAT3 activation. Moreover, protein levels of suppressor of cytokine signaling 1 (SOCS1) and SOCS3 were augmented by osthole and exogenous klotho. The abilities of osthole and exogenous klotho to reverse AGE-induced cellular hypertrophy were verified by the observation that osthole and exogenous klotho inhibited p21Waf1/Cip1/collagen IV/RAGE expression, total protein content, and cell size. CONCLUSION: Consequently, we found that osthole attenuated AGE-induced renal tubular hypertrophy via induction of klotho expression and suppression of the JAK2-STAT1/STAT3 signaling. These results also showed that klotho might be used as a unique molecular target for the treatment of diabetic nephropathy.

SOCS4 expressed by recombinant HSV protects against cytokine storm in a mouse model.

Oncolytic viruses are genetically engineered viruses designed for the treatment of solid tumors, and are often coupled with the antitumor immunity of the host. The challenge of using oncolytic herpes simplex virus (oHSV) as an efficacious oncolytic agent is the potential host tissue damage caused by the production of a range of cytokines following intratumoral oHSV injection. An HSV­suppressor of cytokine signaling 4 (SOCS4) recombinant virus was created to investigate whether it inhibits cytokine storm. Recombinant HSV­SOCS4 and HSV­1(F) were used to infect mice, and levels of several representative cytokines, including monocyte chemoattractant protein­1, interleukin (IL)­1ß, tumor necrosis factor­α, IL­6 and interferon γ, in serum and bronchoalveolar lavage fluid (BALF) of infected mice were determined, and immune cells in BALF and spleen were enumerated. Lung damage, virus titers in the lung, body weight and survival rates of infected mice were also determined and compared between the two groups. The cytokine concentration of HSV­SOCS4­infected mice was significantly decreased compared with that of HSV­1(F)­infected mice in BALF and serum, and a smaller number of cluster of differentiation (CD)11b+ cells of BALF, and CD8+CD62L+ T cells and CD4+CD62L+ T cells of the spleen were also identified in HSV­SOCS4­infected mice. HSV­SOCS4­infected mice exhibited slight lung damage, a decrease in body weight loss and a 100% survival rate. The results of the present study indicated that SOCS4 protein may be a useful regulator to inhibit cytokine overproduction, and that HSV­SOCS4 may provide a possible solution to control cytokine storm and its consequences following induction by oncolytic virus treatment.

The intracellular domain of the leptin receptor prevents mitochondrial depolarization and mitophagy.

Hypothalamic leptin receptor (LR) signaling regulates body weight by balancing food intake and energy expenditure. It is well established that the human LR undergoes ectodomain shedding, but little is known about the fate of the remaining cytosolic domain. This study demonstrates that regulated intramembrane proteolysis (RIP) releases the LR intracellular domain (LR ICD), which translocates to the mitochondria where it binds to SOCS6. This LR ICD-SOCS6 interaction stabilizes both proteins on the mitochondrial outer membrane and requires a functional BC box in SOCS6 for mitochondrial association and a central motif in the LR ICD for SOCS6 binding. The LR ICD prevents CCCP-induced mitochondrial depolarization and mitophagy as shown by lowered Parkin translocation and p62 accumulation. Strict regulation of mitochondrial dynamics in the hypothalamus is known to be essential for body weight homeostasis. This is the first study showing that the LR can directly modulate mitochondrial biology.

Paeoniflorin ameliorates cognitive dysfunction via regulating SOCS2/IRS-1 pathway in diabetic rats.

Paeoniflorin is a natural monoterpene glycoside in Paeonia lactiflora pall with various biological properties including promising anti-inflammatory activity. Current evidences support that inflammatory reaction, oxidative stress, as well as abnormal insulin signaling in the hippocampus are potential causes of tau hyperphosphorylation and finally induce cognitive dysfunction. The present study aims to explore the effects of paeoniflorin on the cognitive deficits and investigate the underlying mechanisms in diabetic rats induced by a high-sucrose, high-fat diet and low dose of streptozotocin (STZ). Paeoniflorin treatment effectively improved the performance of diabetic rats in the Morris water maze test via decreasing escape latency and increasing the spent time in the target quadrant. Immunohistochemistry staining also had shown that tau hyperphosphorylation in the hippocampus was prevented after paeoniflorin administration. This function was correlated with its abilities of reducing the brain inflammatory cytokines (IL-1ß and TNF-α), decreasing suppressor of cytokine signaling 2 (SOCS2) expressions and promoting insulin receptor substrate-1 (IRS-1) activity. Additionally, we also found paeoniflorin administration significantly promoted the phosphorylation levels of protein kinase B (Akt) and glycogen synthase kinase-3ß (GSK-3ß). Together, these results showed that paeoniflorin had beneficial effects on relieving diabetes-associated cognitive deficits via regulating SOCS2/IRS-1 pathway and might provide a feasible method for the treatment of diabetes-associated cognitive dysfunction.

Vitamin D Promotes Pneumococcal Killing and Modulates Inflammatory Responses in Primary Human Neutrophils.

Streptococcus pneumoniae is a major human pathogen and a leading cause of pneumonia, septicemia, and meningitis worldwide. Despite clinical studies linking vitamin D deficiency and pneumonia, molecular mechanisms behind these observations remain unclear. In particular, the effects of vitamin D on neutrophil responses remain unknown. Using pneumococcal strains, primary neutrophils isolated from human blood, and sera from patients with frequent respiratory tract infections (RTIs), we investigated the effects of vitamin D on neutrophil bactericidal and inflammatory responses, including pattern recognition receptors, antimicrobial peptides, and cytokine regulation. We found that vitamin D upregulated pattern recognition receptors, TLR2, and NOD2, and induced the antimicrobial human neutrophil peptides (HNP1-3) and LL-37, resulting in increased killing of pneumococci in a vitamin D receptor-dependent manner. Antibodies targeting HNP1-3 inhibited bacterial killing. Vitamin D supplementation of serum from patients with bacterial RTIs enhanced neutrophil killing. Moreover, vitamin D lowered inflammatory cytokine production by infected neutrophils via IL-4 production and the induction of suppressor of cytokine signaling (SOCS) proteins SOCS-1 and SOCS-3, leading to the suppression of NF-κB signaling. Thus, vitamin D enhances neutrophil killing of S. pneumoniae while dampening excessive inflammatory responses and apoptosis, suggesting that vitamin D could be used alongside antibiotics when treating pneumococcal infections.

Feeding a high dosage of zinc oxide affects suppressor of cytokine gene expression in Salmonella Typhimurium infected piglets.

Suppressor of cytokine signaling (SOCS) proteins play an important role in the regulation of the immune response by inhibiting cytokines. Here we investigated the effects of zinc oxide fed at three different dosages (LZN=57ppm, MZN=167ppm, HZN=2425ppm) to weaned piglets that were or were not orally infected with Salmonella enterica serovar Typhimurium DT 104. We detected higher expression of SOCS3 six days after weaning for all analyzed piglets, regardless of the infection or the zinc feeding, suggesting a stress induced immune response. Whereas, SOCS1 showed only higher transcript amounts in S. Typhimurium infected piglets, especially the LZN group. This might indicate an infection regulating effect of zinc oxide in the infection model. After 42days of infection, the expression of SOCS2, SOCS4, and SOCS7 was increased only in animals fed the highest concentrations of zinc oxide, while non-infected piglets at the age of 56days showed no regulation for these genes. The up-regulation of SOCS genes in the mesenteric lymph nodes of piglets fed a diet with a very high concentration of zinc over 6 weeks suggests that such treatments may impair the immune response.

Resveratrol inhibits STAT3 signaling pathway through the induction of SOCS-1: Role in apoptosis induction and radiosensitization in head and neck tumor cells.

BACKGROUND: Signal transducer and activator of transcription 3 (STAT3) is persistently activated in squamous cell carcinoma of the head and neck (SCCHN) and can cause uncontrolled cellular proliferation and division. HYPOTHESIS: Thus, its targeted abrogation could be an effective strategy to reduce the risk of SCCHN. Resveratrol is known for its anti-cancer efficacy in a variety of cancer models. STUDY DESIGN: The effect resveratrol on STAT3 activation, associated protein kinases, phosphatases, cellular proliferation and apoptosis was investigated. METHODS: We evaluated the effect of resveratrol on STAT3 signaling cascade and its regulated functional responses in SCCHN cells. RESULTS: We found that HN3 and FaDu cells expressed strongly phosphorylated STAT3 on both tyrosine 705 and serine 727 residues as compared to other SCCHN cells. The phosphorylation was completely suppressed by resveratrol in FaDu cells, but not substantially in HN3 cells. STAT3 suppression was mediated through the inhibition of activation of upstream JAK2, but not of JAK1 and Src kinases. Treatment with the protein tyrosine phosphatase (PTP) inhibitor pervanadate reversed the resveratrol-induced down-regulation of STAT3, thereby indicating a critical role for a PTP. We also found that resveratrol induced the expression of the SOCS-1 protein and mRNA. Further, deletion of SOCS-1 gene by siRNA suppressed the induction of SOCS-1, and reversed the inhibition of STAT3 activation. Resveratrol down-regulated various STAT3-regulated gene products, inhibited proliferation, invasion, as well as induced the cell accumulation in the sub-G1 phase and caused apoptosis. Beside, this phytoalexin also exhibited the enhancement of apoptosis when combined with ionizing radiation treatment. CONCLUSION: Our results suggest that resveratrol blocks STAT3 signaling pathway through induction of SOCS-1, thus attenuating STAT3 phosphorylation and proliferation in SCCHN cells.

[Establishment and Evaluation of Hypertensive Rat Model with Excessive Accumulation of Phlegm-dampness Syndrome].

OBJECTIVE: To observe mainfestations of syndrome and biochemical indices of hypertensive model rats with excessive accumulation of phlegm-dampness syndrome (EAPDS), and to explore its possible pathological mechanism. METHODS: EAPDS rat model was prepared in 50 Wistar rats by feeding with high fat forage. Meanwhile, a normal control group consisting of 10 Wistar rats was set up by feeding with normal forage. After 25-week continuous feeding, 22 rats with body weight (BW) and blood pressure (BP) exceeding 25% those of the control group were selected as a model group. BW, BP, blood lipids, and related serological indicators were detected in all rats. Morphological changes of target organs were observed. mRNA expression levels of leptin receptor (LepR), Janus kinase2 (Jak2), signal transducer and activator of transcription 3 (Stat3), suppressor of cytokine signaling-3 (Socs3), angiotensin II receptor type 1 (AT1), angiotensin II receptor type 2 (AT2), phosphatidylinositol 3 kinase (P13K), serine threonine kinase (Akt), nuclear factor of kappa B (NF-κBp65), inhibitor of nuclear factor kappa-B kinase α (IKKα), NF-kappa-B inhibitor ß (lKKß), NF-kappa-B inhibitor α (IKBα), and AMP-activated protein kinase (AMPK) were detected by quantitative real-time PCR (qPCR). Expression levels of AT1 and LepR in aorta were detected by immunohistochemical assay and Western blot respectively. RESULTS: Compared with the control group, BW, BP, and blood lipids increased; serum levels of leptin (Lep) , Ang II, Hcy, ET-1, TNF-α, IL-6, and p2-MG increased, but NO decreased in the model group (P < 0.05, P < 0.01). Aortal endothelial injury and smooth muscle cell proliferation occurred in the model group, accompanied with heart and renal injury. Compared with the control group, mRNA expression levels of LepR, Jak2, Stat3, Socs3, AT1 , PI3K, Akt, NF-κB p65, IKKß, IKBα, and AMPK in aorta were up-regulated significantly (P < 0.05), while the expression of IKKa decreased (P < 0.05). Immunohistochem- ical staining showed, brownish yellow deposit of AT1 and LepR was obviously increased, with more extensively positive distribution. Western blot results showed, as compared with the control group, protein expression levels of AT1 and LepR obviously increased in the model group (P < 0.05). CONCLUSIONS: Model rats exhibited typical syndromes of EAPDS. They put up weight with fat abdomen, gloomy hair, poor appetite, hypersomnia, lowered activities , reduced food intake, loose stool, dark red tongue, white tongue with white, thick, greasy fur. Lep could be taken as one of objective indicators for evaluating hypertension rat model with EAPDS.