Hypocholesterolaemic action of Lactobacillus plantarum VJC38 in rats fed a cholesterol-enriched diet

Invitro and Invivo Analysis of Human Milk Lactic Acid Bacteria Isolates for Their Anti-hypercholesterolemia Actions

The aim of this study was to evaluate the cholesterol lowering ability of Lactic Acid Bacteria (LAB) isolated from human breast milk under in vitro and in vivo conditions. Six LAB isolates namely Lacticaseibacillus casei 1A, Lactobacillus gasseri 5A, Enterococcus faecium 2C, Limosilactobacillus fermentum 3D, Pediococcus acidilactici 1C, and Lactiplantibacillus plantarum 7A, were examined for their bile resistance, bile salt hydrolase activity, cholesterol assimilation and viability in cholesterol rich; DeMan Rogosa and Sharpe broth, simulated gastric, small and upper intestinal conditions. During in vivo experiments, two putative LAB isolates were orally gavage to BALB/c mice, fed with normal basal and cholesterol rich (HCD) diets, daily for a period of 4 weeks. Blood serum analysis including total serum cholesterol, triglycerides, high-density and low-density lipoprotein (LDL) cholesterol levels and total fecal LAB counts of the animals were determined. The isolates in study showed bile resistance and bile salt hydrolysis activity, while significant differences (P < 0.05) were seen in their cholesterol assimilation ability. L. gasseri 5A (195.67%) and L. plantarum 7A (193.78%) displayed highest cholesterol removal percentages, respectively. Animals in HCD, fed with L. gasseri 5A and L. plantarum 7A showed decreased levels of total cholesterol and LDL, compared to the control groups. In HCD group liver weight was increased, while fecal LAB counts were decreased. No changes were observed in behavior or body weight in all experimental groups. In conclusion, L. gasseri 5A and L. plantarum 7A isolated from human breast milk demonstrates significant hypocholesterolaemic actions in vitro and in vivo and might be considered a promising candidates for preventing hypercholesterolemia in man and animals.

Lactobacillus plantarum S9 alleviates lipid profile, insulin resistance, and inflammation in high-fat diet-induced metabolic syndrome rats

Probiotics are considered to play an crucial role in the treatment of high-fat diet (HFD)-induced lipid metabolic diseases, including metabolic syndrome (MS). This study aimed to investigate the effects of Lactobacillus plantarum S9 on MS in HFD-fed rats, and to explore the underlying role of probiotics in the treatment of MS. Sprague-Dawley rats were fed with HFD for 8 weeks, followed by the treatment of L. plantarum S9 for 6 weeks, and The body weight and blood glucose level of rats were detected on time. The results showed that L. plantarum S9 significantly decreased the body weight gain, Lee’s index, and liver index. Additionally, L. plantarum S9 reduced the levels of serum lipids and insulin resistance. L. plantarum S9 also decreased the levels of alanine aminotransferase (ALT) and aspartate transaminase (AST) in liver. Moreover, the serum levels of MS-related inflammatory signaling molecules, including lipopolysaccharide (LPS) and tumor necrosis factor-α (TNF-α), were significantly elevated. Western blot analysis showed that L. plantarum S9 inhibited the activation of nuclear factor-κB (NF-κB) pathway, decreased the expression level of Toll-like receptor 4 (TLR4), suppressed the activation of inflammatory signaling pathways, and reduced the expression levels of inflammatory factors in HFD-fed rats. Moreover, it further decreased the ratios of p-IκBα/IκBα, p-p65/NF-κB p65, and p-p38/p38. In summary, L. plantarum S9, as a potential functional strain, prevents or can prevent onset of MS.

The effect of probiotic fermented milk products on blood lipid concentrations: A systematic review and meta-analysis of randomized controlled trials

AIM

Fermented milk products are suggested as a supplementary therapy to help reduce blood lipid levels. However, the results of clinical studies are conflicting.

DATA SYNTHESIS

This study systematically reviewed 39 randomized controlled trials (n = 2237 participants) to investigate the effect of probiotic fermented milk products on blood lipids. A meta-analysis was performed using random effects models, with weighted mean differences (WMDs) and 95% confidence interval (CI). Statistically significant reductions in blood low-density lipoprotein cholesterol (LDL-C) (WMD: -7.34 mg/dL, 95% CI: from -10.04 to -4.65, and P < 0.001) and total cholesterol (TC) concentrations (WMD: -8.30 mg/dL, 95% CI: from -11.42 to -5.18, and P < 0.001) were observed. No statistically significant effect of probiotic fermented milk was observed on blood high-density lipoprotein cholesterol (HDL-C) and triacylglycerol (TAG) levels. The effect on TC and LDL-C level was more pronounced in men, and a greater reduction in TAG was observed in trials with longer interventions (≥8 weeks) as compared to their counterparts.

CONCLUSIONS

Available evidence suggests that probiotic fermented milk products may help to reduce serum TC and LDL-C cholesterol levels, particularly in men and when they are consumed for ≥8 weeks.