ABSTRACT
The syndrome of dampness stagnancy due to spleen deficiency (DSSD) is relatively common globally. Although the pathogenesis of DSSD remains unclear, evidence has suggested that the gut microbiota might play a significant role. Radix Astragali, used as both medicine and food, exerts the effects of tonifying spleen and qi. Astragalus polysaccharide (APS) comprises a macromolecule substance extracted from the dried root of Radix Astragali, which has many pharmacological functions. However, whether APS mitigates the immune disorders underlying the DSSD syndrome via regulating gut microbiota and the relevant mechanism remains unknown. Here, we used DSSD rats induced by high-fat and low-protein (HFLP) diet plus exhaustive swimming, and found that APS of moderate molecular weight increased the body weight gain and immune organ indexes, decreased the levels of interleukin-1β (IL-1β), IL-6, and endotoxin, and suppressed the Toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) pathway. Moreover, a total of 27 critical genera were significantly enriched according to the linear discriminant analysis effect size (LEfSe). APS increased the diversity of the gut microbiota and changed its composition, such as reducing the relative abundance of Pseudoflavonifractor and Paraprevotella, and increasing that of Parasutterella, Parabacteroides, Clostridium XIVb, Oscillibacter, Butyricicoccus, and Dorea. APS also elevated the contents of short-chain fatty acids (SCFAs). Furthermore, the correlation analysis indicated that 12 critical bacteria were related to the body weight gain and immune organ indexes. In general, our study demonstrated that APS ameliorated the immune disorders in DSSD rats via modulating their gut microbiota, especially for some bacteria involving immune and inflammatory response and SCFA production, as well as the TLR4/NF-κB pathway. This study provides an insight into the function of APS as a unique potential prebiotic through exerting systemic activities in treating DSSD.
Subject(s)
Rats , Animals , NF-kappa B/metabolism , Spleen , Gastrointestinal Microbiome , Toll-Like Receptor 4 , Polysaccharides/pharmacology , Astragalus Plant/metabolism , Immune System Diseases/drug therapy , Body WeightABSTRACT
OBJECTIVE:To study the effect and its mechanism of dexmedetomidine(Dex)on inflammatory response in septic mice. METHODS:Mice were randomly divided into normal control group,model group,miR-146a inhibitor (50 mg/kg)+Dex (50 μg/kg)group,Dex low-dose,medium-dose,high-dose groups(10,30,50 μg/kg),10 in each group. Except for normal con-trol group,other groups were intraperitoneally injected lipopolysaccharide to induce septic models,intraperitoneally injected rele-vant medicines after 0.5 h. After drug intervention for 6 h,miR-146a expression,IRAK1 and TRAF6 mRNA expressions in periph-eral blood mononuclear cells in each group were detected by real-time fluorescence quantitative polymerase chain reaction method. IRAK1,TRAF6 protein expressions in peripheral blood mononuclear cells in each group were detected by Western blot method. TNF-α,IL-6 levels in serum were detected by enzyme-linked immunosorbent method. RESULTS:Compared with normal control group,miR-146a expression,TNF-α and IL-6 levels,IRAK1,TRAF6 mRNA and protein expressions in peripheral blood mononu-clear cells in model group were increased(P0.05). Compared with Dex high-dose group,miR-146a expression,in peripheral blood mononuclear cells in miR-146a inhibitor+Dex group was de-creased;TNF-α and IL-6 levels,IRAK1,TRAF6 protein expressions were increased (P0.05). CONCLUSIONS:Dex can inhibit the inflammatory response in sep-tic mice. The mechanism may associate with inducing miR-146a expression and inhibiting the 2 important adaptor proteins IRAK1, TRAF6 expressions in Toll-like receptor 4/nuclear factor-κB pathway.
ABSTRACT
Objective:To observe the effect of Allicin in cardial fibroblasts (CFs) proliferation and Collagen secretion,and to explore its role on TLR4/NF-κB signal pathway.Methods:CFs of neonatal Wistar rats were isolated and cultured ,then was stimulated with AngⅡ.CFs proliferation was measured by thiazolyl blue ( MTT) assay.The expression of collagenⅠ,collagenⅢ was measured by ELISA.mRNA expression of TLR4 and NF-κB were detected by reverse transcription-polymerase chain reaction ,protein expression of TLR4 and NF-κB were detected with Western blot.Results: Allicin could reduced MTT value of cardial fibroblasts ( P<0.01 ) , and inhibited expression of collagenⅠ,collagenⅢ(P<0.01),which in a dose-dependent manner.Allicin could reduced mRNA expression of TLR4 and NF-κB and protein expression of TLR 4 and NF-κB in CF induced by Ang Ⅱ ( all P<0.01 ) .Conclusion: Allicin can inhibit Myocardial fibrosis ,which mechanism is possible by inhibiting TLR 4/NF-κB signal pathway.
ABSTRACT
Objective To investigate the role of Toll like receptor 4/nuclear factor-κB (TLR4/NF-κB) signal pathway on myocardial dysfunction after cardiac arrest-cardiopulmonary resuscitation (CA-CPR) in animal model. Methods Twenty-six pigs were randomly divided into sham group (n = 6), CA-CPR 12 hours group (n = 10) and CA-CPR 24 hours group (n = 10). The model of CA-CPR was reproduced by endocardial electrical stimulation for 8 minutes followed by CPR, and the pigs in sham group were only given anesthesia and tracheal intubation. The changes in hemodynamics including mean arterial pressure (MAP) and cardiac output (CO), as well as morphology and ultrastructure of myocardial cells were observed before and after CPR. The levels of serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were determined by enzyme linked immunosorbent assay (ELISA), and protein and mRNA expressions of TLR4/NF-κB in the myocardium were determined by Western Blot and real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-PCR), respectively. Results Hemodynamic disturbance and myocardial serious injury were observed in CA-CPR groups. Compared with sham group, the levels of serum TNF-α were markedly increased 0.5 hour after return of spontaneous circulation (ROSC) in CA-CPR 12 hours and 24 hours groups (pg/L: 62.49±6.66, 48.39±2.37 vs. 10.75±0.74, both P < 0.05), and peaked at 2 hours (pg/L: 70.93±5.51, 66.03±2.60 vs. 10.87±0.91, both P < 0.05) followed by a gradual decline. The levels of serum IL-6 at 0.5 hours after ROSC in CA-CPR 12 hours and 24 hours groups were markedly higher than those of sham group (pg/L: 14.42±1.99, 11.23±1.12 vs. 8.75±0.74, both P < 0.05), and peaked at 12 hours (pg/L: 36.50±2.91, 38.15±1.26 vs. 8.88±0.62, both P < 0.05) followed by a gradual decline. The protein expressions of TLR4 and NF-κB in the myocardium were significantly increased in CA-CPR 12 hours and 24 hours groups as compared with sham group [TLR4 protein (gray value): 0.11±0.03, 0.24±0.05 vs. 0.05±0.02; NF-κB protein (gray value): 0.27±0.04, 0.24±0.03 vs. 0.09±0.02, all P < 0.05]. The mRNA levels of TLR4 in CA-CPR 12 hours and 24 hours groups were increased by approximately (9.93±1.07) folds and (9.21±1.27) folds of sham group respectively, and NF-κB mRNA expressions were increased by (4.44±0.96) folds and (6.09±0.81) folds of sham group respectively (all P < 0.01). Conclusion Activation of TLR4/NF-κB signal pathway may be one of the main pathological mechanisms of post resuscitation myocardial injury in a porcine model of CA-CPR.