Background An imbalance in the rumen microbiota caused by high-concentrate diets(HCD)is a significant endogenous trigger of mastitis.However,the underlying mechanisms remain largely unknown.Microbial extracellular ves...Background An imbalance in the rumen microbiota caused by high-concentrate diets(HCD)is a significant endogenous trigger of mastitis.However,the underlying mechanisms remain largely unknown.Microbial extracellular vesicles(mEVs)are critical mediators of microbe-host communication.However,the role of mEVs in rumen microbiota-mediated mastitis has not yet been reported.In this study,we used an HCD-induced rumen microbiota dysbiosis model to investigate the role of mEVs-derived from rumen microbiota in the pathogenesis of mastitis.Results Our results indicate that HCD leads to mastitis and systemic inflammation.Meanwhile,HCD-fed goats exhibited substantial rumen microbiota dysbiosis and the disruption of the rumen barrier.Transplanting rumen microbiota from HCD goats into mice induced both mastitis and systemic inflammation in the recipients.Specifically,HCD increases the production of mEVs carrying microbial DNA,which can translocate across the compromised rumen barrier to the mammary gland,triggering a mammary inflammatory response via activation of the cGAS-STING-NF-κB/NLRP3 pathway.Furthermore,treating mice with mEVs isolated from the rumen fluid of HCD goats directly induced mastitis,whereas depletion of microbial DNA attenuated mEVs-induced mastitis.Conclusion Our findings suggest that HCD induces rumen microbiota dysbiosis and impairs rumen barrier function.This dysfunction leads to an increase in microbial DNA-containing mEVs,which subsequently leak into the mammary gland.Once there,these mEVs activate the cGAS-STING-NF-κB/NLRP3 signaling pathway,ultimately inducing mastitis.This study provides a new perspective on the“rumen microbiota-mammary gland axis”and enhances the understanding of the pathogenesis of mastitis.展开更多
Objective:To investigate the antifibrotic effects of curcumin in a transverse aortic constriction(TAC)mouse model and elucidate its molecular mechanisms.Methods:Male C57BL/6 mice underwent TAC and received vehicle,low...Objective:To investigate the antifibrotic effects of curcumin in a transverse aortic constriction(TAC)mouse model and elucidate its molecular mechanisms.Methods:Male C57BL/6 mice underwent TAC and received vehicle,low-dose curcumin(50 mg/kg),high-dose curcumin(200 mg/kg),high-dose curcumin plus a scrambled control antagomir,or high-dose curcumin plus anti-miR-29b treatments.Cardiac function was assessed by echocardiography.Fibrosis was evaluated by histology,collagen volume fraction,and hydroxyproline content.Expression of miR-29b,HDAC4,and fibrosis-related markers(Col1a1,Col3a1,TGF-β1)was measured by quantitative RT-PCR and Western blotting assays.Myocardial procollagen type I carboxy-terminal propeptide was determined by ELISA,and HDAC4-specific enzymatic activity was assayed using a fluorogenic kit.Results:Curcumin improved cardiac function,reduced fibrosis,restored miR-29b expression,and suppressed HDAC4 expression and activity in a dose-dependent manner.Furthermore,curcumin decreased myocardial procollagen type I carboxy-terminal propeptide levels,confirming reduced collagen synthesis.Anti-miR-29b administration partially abrogated the antifibrotic and cardioprotective effects of curcumin.Conclusions:Curcumin attenuates pressure overload-induced cardiac fibrosis and dysfunction in a TAC mouse model via modulation of the miR-29b/HDAC4 axis and suppression of collagen synthesis.展开更多
目的探讨益气活血化浊解毒方调控KAT3B/STING轴介导的小胶质细胞极化对缺血性脑卒中大鼠神经功能的影响。方法复制缺血性脑卒中大鼠模型。将复制成功的60只大鼠分为缺血性脑卒中组、益气活血化浊解毒方低剂量组(低剂量组)、益气活血化...目的探讨益气活血化浊解毒方调控KAT3B/STING轴介导的小胶质细胞极化对缺血性脑卒中大鼠神经功能的影响。方法复制缺血性脑卒中大鼠模型。将复制成功的60只大鼠分为缺血性脑卒中组、益气活血化浊解毒方低剂量组(低剂量组)、益气活血化浊解毒方高剂量组(高剂量组)、益气活血化浊解毒方高剂量+2,5-己酮可可碱(DMXAA)组(高剂量+DMXAA组),每组15只。另取15只正常大鼠为Sham组。低剂量组大鼠灌胃0.2 mL 27.5 g/mL的益气活血化浊解毒方药液,高剂量组大鼠灌胃0.2 mL 55.0 g/mL的益气活血化浊解毒方药液,高剂量+DMXAA组大鼠灌胃0.2 mL 55.0 g/mL的益气活血化浊解毒方药液和25 mg/kg的DMXAA,Sham组和缺血性脑卒中组给予等体积生理盐水代替药物;除高剂量+DMXAA组外,其余组大鼠再给予等体积二甲基亚砜溶液灌胃,1 d/次,连续4周。Zea-Longa评分和网屏试验评分评估大鼠神经功能和神经行为学;检测大鼠脑组织含水量;TTC染色法检测大鼠脑梗死面积;酶联免疫吸附试验检测大鼠血清LDH和NGF水平和缺血侧皮层组织TNF-α、IL-6、IL-10水平;HE染色观察大鼠缺血侧皮层组织病理变化;Western blotting检测大鼠缺血侧皮层组织iNOS、Iba1、CD68、CD40、CD206、Arg-1、Cleaved caspase-3、KAT3B、STING蛋白表达。结果缺血性脑卒中组大鼠Zea-Longa评分和网屏试验评分、脑组织含水量、脑梗死面积百分比均高于Sham组(P<0.05),低剂量组和高剂量组大鼠Zea-Longa评分和网屏试验评分、脑组织含水量、脑梗死面积百分比均低于缺血性脑卒中组(P<0.05),高剂量+DMXAA组大鼠Zea-Longa评分和网屏试验评分、脑组织含水量、脑梗死面积百分比均高于高剂量组(P<0.05)。缺血性脑卒中组大鼠NGF和IL-10水平低于Sham组,LDH、TNF-α和IL-6水平高于Sham组(P<0.05);低剂量组和高剂量组大鼠NGF和IL-10水平高于缺血性脑卒中组,LDH、TNF-α和IL-6水平低于缺血性脑卒中组(P<0.05);高剂量+DMXAA组大鼠NGF和IL-10水平低于高剂量组,LDH、TNF-α和IL-6高于高剂量组(P<0.05)。与缺血性脑卒中组比较,低剂量组和高剂量组缺血侧皮层神经元形态有明显改善。缺血性脑卒中组大鼠缺血侧皮层组织中iNOS、Iba1、CD68和CD40蛋白相对表达量比Sham组高,CD206和Arg-1蛋白相对表达量比Sham组低(P<0.05);低剂量组和高剂量组大鼠缺血侧皮层组织中iNOS、Iba1、CD68和CD40蛋白相对表达量比缺血性脑卒中组低,CD206和Arg-1蛋白相对表达量比缺血性脑卒中组高(P<0.05);高剂量+DMXAA组大鼠缺血侧皮层组织中iNOS、Iba1、CD68和CD40蛋白相对表达量比高剂量组高,CD206和Arg-1蛋白相对表达量比高剂量组低(P<0.05)。结论益气活血化浊解毒方可调节缺血性脑卒中大鼠小胶质细胞极化,减轻神经炎症和神经损伤,改善神经功能,可能与抑制KAT3B/STING轴有关。展开更多
基金supported by the National Natural Science Foundation of China(32330105 and 32301247)National Key R&D Program of China(2023YFD1801100)。
文摘Background An imbalance in the rumen microbiota caused by high-concentrate diets(HCD)is a significant endogenous trigger of mastitis.However,the underlying mechanisms remain largely unknown.Microbial extracellular vesicles(mEVs)are critical mediators of microbe-host communication.However,the role of mEVs in rumen microbiota-mediated mastitis has not yet been reported.In this study,we used an HCD-induced rumen microbiota dysbiosis model to investigate the role of mEVs-derived from rumen microbiota in the pathogenesis of mastitis.Results Our results indicate that HCD leads to mastitis and systemic inflammation.Meanwhile,HCD-fed goats exhibited substantial rumen microbiota dysbiosis and the disruption of the rumen barrier.Transplanting rumen microbiota from HCD goats into mice induced both mastitis and systemic inflammation in the recipients.Specifically,HCD increases the production of mEVs carrying microbial DNA,which can translocate across the compromised rumen barrier to the mammary gland,triggering a mammary inflammatory response via activation of the cGAS-STING-NF-κB/NLRP3 pathway.Furthermore,treating mice with mEVs isolated from the rumen fluid of HCD goats directly induced mastitis,whereas depletion of microbial DNA attenuated mEVs-induced mastitis.Conclusion Our findings suggest that HCD induces rumen microbiota dysbiosis and impairs rumen barrier function.This dysfunction leads to an increase in microbial DNA-containing mEVs,which subsequently leak into the mammary gland.Once there,these mEVs activate the cGAS-STING-NF-κB/NLRP3 signaling pathway,ultimately inducing mastitis.This study provides a new perspective on the“rumen microbiota-mammary gland axis”and enhances the understanding of the pathogenesis of mastitis.
基金supported by China International Medical Foundation(Z-2019-42-1908-4)Natural Science Basic Research Program of Shaanxi Province(2019JM-440).
文摘Objective:To investigate the antifibrotic effects of curcumin in a transverse aortic constriction(TAC)mouse model and elucidate its molecular mechanisms.Methods:Male C57BL/6 mice underwent TAC and received vehicle,low-dose curcumin(50 mg/kg),high-dose curcumin(200 mg/kg),high-dose curcumin plus a scrambled control antagomir,or high-dose curcumin plus anti-miR-29b treatments.Cardiac function was assessed by echocardiography.Fibrosis was evaluated by histology,collagen volume fraction,and hydroxyproline content.Expression of miR-29b,HDAC4,and fibrosis-related markers(Col1a1,Col3a1,TGF-β1)was measured by quantitative RT-PCR and Western blotting assays.Myocardial procollagen type I carboxy-terminal propeptide was determined by ELISA,and HDAC4-specific enzymatic activity was assayed using a fluorogenic kit.Results:Curcumin improved cardiac function,reduced fibrosis,restored miR-29b expression,and suppressed HDAC4 expression and activity in a dose-dependent manner.Furthermore,curcumin decreased myocardial procollagen type I carboxy-terminal propeptide levels,confirming reduced collagen synthesis.Anti-miR-29b administration partially abrogated the antifibrotic and cardioprotective effects of curcumin.Conclusions:Curcumin attenuates pressure overload-induced cardiac fibrosis and dysfunction in a TAC mouse model via modulation of the miR-29b/HDAC4 axis and suppression of collagen synthesis.
文摘目的探讨益气活血化浊解毒方调控KAT3B/STING轴介导的小胶质细胞极化对缺血性脑卒中大鼠神经功能的影响。方法复制缺血性脑卒中大鼠模型。将复制成功的60只大鼠分为缺血性脑卒中组、益气活血化浊解毒方低剂量组(低剂量组)、益气活血化浊解毒方高剂量组(高剂量组)、益气活血化浊解毒方高剂量+2,5-己酮可可碱(DMXAA)组(高剂量+DMXAA组),每组15只。另取15只正常大鼠为Sham组。低剂量组大鼠灌胃0.2 mL 27.5 g/mL的益气活血化浊解毒方药液,高剂量组大鼠灌胃0.2 mL 55.0 g/mL的益气活血化浊解毒方药液,高剂量+DMXAA组大鼠灌胃0.2 mL 55.0 g/mL的益气活血化浊解毒方药液和25 mg/kg的DMXAA,Sham组和缺血性脑卒中组给予等体积生理盐水代替药物;除高剂量+DMXAA组外,其余组大鼠再给予等体积二甲基亚砜溶液灌胃,1 d/次,连续4周。Zea-Longa评分和网屏试验评分评估大鼠神经功能和神经行为学;检测大鼠脑组织含水量;TTC染色法检测大鼠脑梗死面积;酶联免疫吸附试验检测大鼠血清LDH和NGF水平和缺血侧皮层组织TNF-α、IL-6、IL-10水平;HE染色观察大鼠缺血侧皮层组织病理变化;Western blotting检测大鼠缺血侧皮层组织iNOS、Iba1、CD68、CD40、CD206、Arg-1、Cleaved caspase-3、KAT3B、STING蛋白表达。结果缺血性脑卒中组大鼠Zea-Longa评分和网屏试验评分、脑组织含水量、脑梗死面积百分比均高于Sham组(P<0.05),低剂量组和高剂量组大鼠Zea-Longa评分和网屏试验评分、脑组织含水量、脑梗死面积百分比均低于缺血性脑卒中组(P<0.05),高剂量+DMXAA组大鼠Zea-Longa评分和网屏试验评分、脑组织含水量、脑梗死面积百分比均高于高剂量组(P<0.05)。缺血性脑卒中组大鼠NGF和IL-10水平低于Sham组,LDH、TNF-α和IL-6水平高于Sham组(P<0.05);低剂量组和高剂量组大鼠NGF和IL-10水平高于缺血性脑卒中组,LDH、TNF-α和IL-6水平低于缺血性脑卒中组(P<0.05);高剂量+DMXAA组大鼠NGF和IL-10水平低于高剂量组,LDH、TNF-α和IL-6高于高剂量组(P<0.05)。与缺血性脑卒中组比较,低剂量组和高剂量组缺血侧皮层神经元形态有明显改善。缺血性脑卒中组大鼠缺血侧皮层组织中iNOS、Iba1、CD68和CD40蛋白相对表达量比Sham组高,CD206和Arg-1蛋白相对表达量比Sham组低(P<0.05);低剂量组和高剂量组大鼠缺血侧皮层组织中iNOS、Iba1、CD68和CD40蛋白相对表达量比缺血性脑卒中组低,CD206和Arg-1蛋白相对表达量比缺血性脑卒中组高(P<0.05);高剂量+DMXAA组大鼠缺血侧皮层组织中iNOS、Iba1、CD68和CD40蛋白相对表达量比高剂量组高,CD206和Arg-1蛋白相对表达量比高剂量组低(P<0.05)。结论益气活血化浊解毒方可调节缺血性脑卒中大鼠小胶质细胞极化,减轻神经炎症和神经损伤,改善神经功能,可能与抑制KAT3B/STING轴有关。