魔芋甘露低聚糖增强肠道屏障功能改善酒精性中枢神经损伤的实验研究

Konjac Mannan Oligosaccharides enhanced intestinal barrier function to improve alcoholic nervous injury

目的慢性酒精摄入导致的大脑过度神经炎症是中枢神经损伤的重要危险因素。本实验主要研究魔芋甘露低聚糖(Konjac mannan oligosaccharides,KMOS)保护酒精喂养小鼠中枢神经炎症的作用及其机制。方法C57BL/6J小鼠采用Gao-binge法制备慢性酒精喂养小鼠模型,同时使用不同剂量的KMOS灌胃干预,喂养6周。评估脑组织皮层和海马区域神经元损伤和小胶质细胞活化情况,观察结肠组织损伤情况和炎症反应,检测血清LPS浓度。体外使用LPS直接刺激Caco-2细胞制备肠黏膜损伤模型。结果慢性酒精的摄入可导致小鼠大脑神经元损伤,而不同剂量的KMOS均能有效降低酒精喂养小鼠脑组织中小胶质细胞的活化状态,降低NLRP3炎性小体活化导致的炎性因子表达,减轻神经元受损。对结肠组织的分析结果表明,KMOS的使用有效地降低了酒精喂养小鼠外周血中内毒素LPS的浓度,减轻酒精喂养小鼠结肠组织的病理损伤和炎性反应,增强肠道组织Occludin表达。体外实验也显示,KMOS能显著抑制酒精暴露下Caco-2细胞的炎性反应,显著提高Occludin表达水平。结论KMOS的使用可有效的抑制酒精摄入导致的肠道炎症,修复肠道屏障,减少肠道LPS进入脑组织,降低小胶质细胞活化导致的过度神经炎症反应,进而改善脑神经元损伤。KMOS具有预防酒精性神经损伤的潜力。

Aim Excessive cerebral inflammation caused by chronic alcohol intake is an important risk factor for central nervous system injury.The purpose of this study was to explore the protective effect of konjac mannan oligosaccharide(KMOS)on central nervous system inflammation in alcohol-fed mice and its mechanism.Methods The chronic alcohol fed model of C57BL/6J mice was established using Gao-binge method.And the different doses of KMOS were gavaged every day for 6 weeks.The neuronal damage and microglia activation were evaluated in cerebral cortex and hippocampus.The damage of colon tissue was assessed and serum LPS concentrations were measured.In vitro,Caco-2 cells were stimulated with LPS to establish intestinal mucosal injury model.Results Chronic alcohol intake can cause brain neuron damage in mice,and different doses of KMOS effectively reduced the activation state of microglia,decreased the expression of inflammatory factors caused by the activation of the NLRP3 inflammasome and alleviated neuronal damage in the brain tissue of alcohol-fed mice.The results of colon tissue analysis showed that the use of KMOS effectively reduced the concentration of endotoxin LPS in serum of alcohol-fed mice,alleviated the pathological injury and inflammatory response of colon tissue,and enhanced the expression of Occludin in intestinal tissue.In vitro experiments also showed that KMOS significantly inhibited the inflammatory reaction of Caco-2 cells exposed to alcohol and increased the expression of Occludin protein.Conclusions KMOS treatment effectively inhibited intestinal inflammation caused by alcohol intake,repaired intestinal barrier to prevent the entry of intestinal LPS into brain tissue,decreased the activation of microglia,and then improved brain neuron damage.KMOS had the potential to prevent alcoholic nerve injury.