Protective effects of two Lactobacillus plantarum strains in hyperlipidemic mice

摘要

AIM:To investigate the effects of Lactobacillus plantarum(L.plantarum) CAI6 and L.plantarum SC4 on hyperlipidemic mice.METHODS:Male Kunming mice were fed a highcholesterol diet for 28 d to construct hyperlipidemic models.Hyperlipidemic mice and normal mice were assigned to 3 groups which were separately treated with L.plantarum CAI6,L.plantarum SC4,and physiological saline through oral gavage for 28 d.Total cholesterol(TC),triglycerides(TG),high-density lipoprotein cholesterol(HDL-C),and low-density lipoprotein cholesterol(LDL-C) levels were measured by commercially available enzyme kits.FACS Calibur flow cytometry was used to examine hepatic and renal nuclear factor-erythroid 2-related factor 2(Nrf2) expression.The morphology of livers was checked by hematoxylin and eosin staining and optical microscope observation.RESULTS:Compared with normal mice,hyperlipidemic mice possessed significantly higher TC(3.50 ± 0.43 vs 2.89 ± 0.36,P < 0.01),TG(1.76 ± 0.07 vs 1.10 ± 0.16,P < 0.01),and LDL-C(1.72 ± 0.20 vs 0.82 ± 0.10,P < 0.01) levels,resulting in an increase of atherogenic index(AI)(2.34 ± 1.60 vs 0.93 ± 0.55,P < 0.05) and LDL-C/HDL-C ratio(1.43 ± 0.12 vs 0.51 ± 0.16,P < 0.05).After treatment with L.plantarum CAI6/L.plantarum SC4,TG(1.43 ± 0.27/1.54 ± 0.10 vs 1.76 ± 0.07,P < 0.01/P < 0.05) and LDL-C(1.42 ± 0.07/1.47 ± 0.12 vs 1.72 ± 0.20,P < 0.01/P < 0.01) in hyperlipidemic mice significantly decreased.In addition,TC,HDL-C,AI,and LDL-C/HDL-C ratio were all positively changed.Meanwhile,the treatment markedly alleviated hepatic steatosis and significantly stimulated Nrf2 expression(73.79 ± 0.80/72.96 ± 1.22 vs 54.94 ± 1.84,P < 0.01/P < 0.01) in hepatocytes of hyperlipidemic mice.CONCLUSION:L.plantarum CAI6 and L.plantarum SC4 may protect against cardiovascular disease by lipid metabolism regulation and Nrf2-induced antioxidative defense in hyperlipidemic mice.