棒状腐败乳杆菌Lc7对高脂血症仓鼠的降脂及其肠道菌群调节作用

Loigolactobacillus coryniformis Lc7 reduces serum lipids and modulates gut microbiota in hyperlipidemic hamsters

摘要:

【背景】高脂血症是心血管疾病的主要危险因素，其与肠道菌群的变化密切相关。乳酸菌等益生菌可通过调节肠道菌群结构发挥降脂功能。【目的】研究棒状腐败乳杆菌(Loigolactobacillus coryniformis) Lc7对高脂血症仓鼠血脂和肠道菌群的影响。【方法】通过饲喂高脂饲料构建仓鼠高脂血症模型，灌胃L. coryniformis Lc7菌悬液，干预6周后检测仓鼠血脂水平、血清炎症因子和脂多糖水平，观察肝组织和附睾脂肪组织的病理变化，采用16S rRNA基因扩增子测序分析盲肠内容物中的肠道菌群。【结果】L. coryniformis Lc7干预显著降低了高脂血症仓鼠血清总胆固醇(P<0.001)、甘油三酯和低密度脂蛋白胆固醇(P<0.05)的水平、升高了血清高密度脂蛋白胆固醇的水平(P<0.001)、降低了血清白细胞介素-1β (P<0.05)、白细胞介素-6 (P<0.01)和脂多糖(P<0.05)的水平，减轻了高脂饮食引起的肝组织损伤和附睾脂肪组织脂肪堆积，改善了肠道菌群的多样性和结构，降低了厚壁菌门与拟杆菌门相对丰度的比值(P<0.05)，升高了颤杆菌克属和拟杆菌属等肠道有益菌的相对丰度，降低了螺杆菌属和Negativibacillus的相对丰度，螺杆菌属的相对丰度与总胆固醇浓度呈正相关(P<0.01)。【结论】L. coryniformis Lc7可改善仓鼠脂质代谢紊乱，调节肠道菌群，缓解高脂血症。提示L. coryniformis Lc7可以作为预防和治疗高脂血症的候选菌株。

Abstract:

[Background] Hyperlipidemia, a key risk factor for cardiovascular diseases, is associated with gut microbiota. Lactic acid bacteria and other probiotics can lower the blood lipid levels by regulating gut microbiota. [Objective] To investigate the effects of Loigolactobacillus coryniformis Lc7 on the serum lipid levels and gut microbiota in hyperlipidemic hamsters. [Methods] The hyperlipidemic hamster model was established with a high-fat diet and then administrated with L. coryniformis Lc7 suspension or phosphate buffered saline by gavage for 6 weeks. The serum levels of lipids and inflammatory cytokines and the pathological changes of the liver and epididymal adipose tissues in hamsters were measured. Furthermore, 16S rRNA gene amplicon sequencing was employed to analyze the gut microbiota in cecal contents. [Results] Oral administration of L. coryniformis Lc7 in hyperlipidemic hamsters lowered the serum levels of total cholesterol (P<0.001), triglyceride, and low-density lipoprotein cholesterol (P<0.05) and elevated the serum level of high-density lipoprotein cholesterol (P<0.001). Moreover, it reduced the serum levels of interleukin-1β (P<0.05), interleukin-6 (P<0.01), and lipopolysaccharide (P<0.05) and attenuated liver tissue injury and epididymal fat accumulation induced by the high-fat diet. Furthermore, the intervention improved the diversity and structure of gut microbiota, as manifested by the decreased ratio of Firmicutes to Bacteroidota (P<0.05), increased relative abundance of beneficial bacteria such as Oscillibacter and Bacteroides, and decreased relative abundance of Helicobacter and Negativibacillus in hyperlipidemic hamsters. The relative abundance of Helicobacter was positively correlated with the concentration of total cholesterol (P<0.01).[Conclusion] L. coryniformis Lc7 can ameliorate lipid metabolism disorder and modulate gut microbiota in hyperlipidemic hamsters, serving as a promising candidate for the prevention and treatment of hyperlipidaemia.