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Objective To explore the mechanism of short-chain fatty acids in alleviating γδT cell-mediated inflammatory response. Methods A certain concentration of short-chain fatty acids was used to intervene in rat intestinal-derived γδT cells. CCK-8 was used to detect the effect of shortchain fatty acids on γδT activity. ELISA was used to detect the content of the IL-17A, RT-qPCR was utilized to detect the expression of the IL-17A, and flow cytometry was applied to analyze the IL-17+ γδT cell frequency. The effect of SCFAs on IL-17A and NF-κB signaling pathway in γδT cells were observed by Western blot. Results CCK-8 assay showed that the concentration of sodium acetate was less than or equal to 0.5 mmol/L, and the concentrations of sodium propionate, sodium butyrate, and mixed short-chain fatty acids were less than or equal to 0.25 mmol/L, indicating no inhibitory effect on the proliferation of γδT cells. ELISA and RT-qPCR showed that the treatment of γδT cells with sodium propionate, sodium butyrate, and mixed short-chain fatty acids significantly decreased the levels of IL-17A compared with the control group. Flow cytometry revealed a significant decrease in the proportion of IL-17+ γδT cells under the treatment of sodium propionate, sodium butyrate, mixed shortchain fatty acids, and TSA intervention. Western blot found that sodium propionate, sodium butyrate, and mixed shortchain fatty acids could inhibit the expression of IL-17A and IKK, as well as the phosphorylation level of NF-κB. Conclusion Shortchain fatty acids could inhibit the activation of IL-17A and NF-κB signaling pathway in γδT cells, thereby alleviating the inflammatory response in the body. [ABSTRACT FROM AUTHOR]

Cellulose is an important abundant renewable resource on Earth, and the microbial cellulose utilization mechanism has attracted extensive attention. Recently, some signalling molecules have been found to regulate cellulose utilization and the discovery of underlying signals has recently attracted extensive attention. In this paper, we found that the hydrogen sulfide (H2S) concentration under cellulose culture condition increased to approximately 2.3-fold compared with that under glucose culture condition in Ganoderma lucidum. Further evidence shown that cellulase activities of G. lucidum were improved by 18.2-27.6% through increasing H2S concentration. Then, we observed that the carbon repressor CreA inhibited H2S biosynthesis in G. lucidum by binding to the promoter of cbs, a key gene for H2S biosynthesis, at "CTGGGG". In our study, we reported for the first time that H2S increased the cellulose utilization in G. lucidum, and analyzed the mechanism of H2S biosynthesis induced by cellulose. This study not only enriches the understanding of the microbial cellulose utilization mechanism but also provides a reference for the analysis of the physiological function of H2S signals. Insights into the role and regulation of hydrogen sulfide (H2S) in cellulose utilization in Ganoderma lucidum. [ABSTRACT FROM AUTHOR]

Toll-like receptor (TLR) 7, a transmembrane signal transduction receptor expressed on the surface of endosomes, has become an attractive target for antiviral and cancer immunotherapies. TLR7 can induce signal transduction by recognizing single-stranded RNA or its analogs, leading to the release of cytokines such as IL-6, IL-12, TNF-α and type-I IFN. Activation of TLR7 helps to enhance immunogenicity and immune memory by stimulating immune cells. Herein, we identified a novel selective TLR7 agonist, GY101, and determined its ability to activate TLR7. In summary, in vitro , compound GY101 significantly induced the secretion of IL-6, IL-12, TNF-α and IFN-γ in mouse splenic lymphocytes; in vivo , peritumoral injection of GY101 significantly suppressed colon cancer CT26, as well as poorly immunogenic B16–F10 and 4T1 cancer cell-derived tumor growth by activating the infiltration of lymphocytes and polarization of M2-like macrophages into M1-like macrophages. These results demonstrate that GY101 , as a potent TLR7 agonist, holds great potential for cancer immunotherapy. [Display omitted] • Identified a selective TLR7 agonist GY101 to activate TLR7 • GY101 significantly induced the secretion of IL-6, IL-12, TNF-α and IFN-γ in mouse splenic lymphocytes • GY101 activate infiltration of lymphocytes and polarization of M2-like macrophages in vivo • GY101 significantly suppressed CT26, as well as B16F10 and 4T1 colon cancer cell-derived tumor growth in vivo. [ABSTRACT FROM AUTHOR]

Shuangshen granules (SSG), a nationally patented Chinese medicinal formula, including Panax quinquefolium L., Panax notoginseng (Burkill) F. H. Chen, and Cordyceps sinensis (Berk.) Sacc., has demonstrated remarkable therapeutic effects on pancreatic cancer in clinical treatment for nearly 10 years. Previous pharmacological researches have found that its main components, including ginsenosides and cordycepin have anticancer or preventive effects on pancreatic ductal adenocarcinoma (PDAC), which may be associated with immune metabolism. However, the underlying pharmacological mechanism of SSG in the truncation effect of PDAC progression is still unclear. To comprehensively understand the infiltrating immune cells during the different stages of the PDAC development chain and search for immune-related biomarkers that could potentially serve as drug targets through bioinformatic analysis. Meanwhile, the truncation effect of SSG on PDAC progression was also investigated. The gene expression profiles at different PDAC developmental stages, including normal pancreas, pancreatic intraepithelial neoplasia (PanIN), and PDAC, were retrieved from the GEO database. The GEO2R tool was used to identify differentially expressed genes among the three groups. Functional enrichment analysis was performed with the GSEA software and Metascape platform. The CIBERSORT algorithm evaluated immune cell infiltration in the three groups, and immune-related biomarkers were identified. Correlation analysis was employed to examine the association between immune cells and the biomarkers. One of these biomarkers was selected for immunohistochemistry validation in human samples. Lastly, the effectiveness of SSG against PDAC progression and the influence on the selected biomarker were validated in vivo. The underlying pharmacological mechanisms were also explored. One dataset was obtained, where the functional enrichment of DEGs primarily involved immune effector processes and cytokine production of immune cells. The differential immune cells reflected during the progression from PanIN to PDAC were B memory cells, monocytes, M2 macrophages, and activated dendritic cells. The upregulation of ACTA2 was closely associated with M2 macrophage regulation. The immunohistochemistry on human samples validated significant differences in ACTA2 expression levels as the PDAC progressed. Moreover, animal experiments revealed that the national patented drug SSG ameliorated the pathological changes, decreased the expression of ACTA2 and its functional protein α-smooth muscle actin during PDAC progression. The underlying pharmacological mechanism was related to the regulation of macrophage polarization and downregulation of TGF-β/Smad signaling pathway. The immunosuppressive environment changes during the PDAC progression. ACTA2 is a potential immuned-target for drug prevention of PDAC, while SSG could be a promising drug candidate. Pictures in graphical abstract were download from http://image.baidu.com/. [Display omitted] [ABSTRACT FROM AUTHOR]

Pinctada martensii (Dunker) and other marine shellfish flesh have been traditionally used in China as folk remedies regulate blood sugar. To investigate the main active constituents and the pharmacological mechanism of Pinctada martensii flesh enzymatic hydrolysate (PMH) against T2DM. The hypoglycemic activity of enzymolysis peptides from Pinctada martensii was evaluated by using db/db mice, through the influence of glycemic index, blood lipid and key protein expression of PI3K-Akt pathway. In addition, label-free quantitative proteomics was used to screen the key proteins for Pinctada martensii hydrolysate (PMH) to improve T2DM, and Western blot and qRT-PCR were used to verify the expression difference of differential proteins at protein and mRNA levels between different groups. PMH were prepared and characterized. In vivo investigations revealed that the PMH could regulate blood glucose and improve glucose tolerance and insulin tolerance, reduced serum total cholesterol, triglyceride, low-density lipoprotein cholesterol levels and increase high-density lipoprotein cholesterol levels in db/db mice. Western blot results showed that PMH could up-regulate IRS-1, P-PI3K/PI3K and P-Akt/Akt levels in db/db mice. Label-free quantitative proteomic approach was used to analyze the proteome in db/db mouse liver, 231 proteins were reversed significantly (p < 0.05), and these proteins were involved in oxidative phosphorylation, glycolysis/gluconeogenesis and other pathways. Further screened 15 proteins with FC > 1.2 could be enriched in the retinol metabolic pathway, and the proteins in this pathway were also verified. PMH has hypoglycemic effect and can be used as a potential natural T2DM intervener. The hypoglycemic activity of PMH is related to its regulation of the PI3K/AKT pathway. The PI3K/AKT pathway and the retinol pathway are considered as another potential pathway for PMH to exert hypoglycemic effects. [Display omitted] • Pinctada martensii hydrolysate (PMH) exhibit hypoglycemic effects and its peptides are characterized. • Hypoglycemic activity of PMH is associated with its regulation of PI3K/AKT pathway. • Retinol pathway identified as another potential pathway for PMH to exert hypoglycemic effects. [ABSTRACT FROM AUTHOR]