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

This study was conducted to evaluate hypocholesterolaemic activity of probiotic strains Lactobacillus plantarum VJC38 and VJI21 in Wistar albino rats fed a cholesterol-enriched diet. The experimental animals were divided into five groups (n = 6) viz., normal diet control group (NDC), hypercholesterolaemic diet (HD) control group (HDC), HD supplemented with 3 × 108 CFU/ml of L. plantarum VJC38 group (HD-C38), HD supplemented with 3 × 108 CFU/ml of L. plantarum VJI21 group (HD-I21), and HD supplemented with 3 × 108 CFU/ml of L. rhamnosus GG group (HD-GG) as positive control. Animals were administered bacterial culture by oral gavage once daily for 45 days. After trial, animals were sacrificed and blood samples were collected. Serum total cholesterol (T-CHO), triglyceride (TG), high-density lipoprotein (HDL) cholesterol, glucose, glutamyl pyruvate transaminase (GPT), and glutamyl oxaloacetate transaminase (GOT) levels were determined. Serum low-density lipoprotein (LDL) cholesterol levels were estimated using the Friedewald’s equation. Liver and fecal lipid contents and fecal cholic acids were measured. Serum T-CHO levels were significantly decreased by 15.6 and 17.4% in the HD-GG and HD-C38 groups, respectively, but not in the HD-I21 group compared with HDC group (P < 0.05). HD-GG and HD-C38 groups showed 26.3 and 27.2% reduction in serum LDL cholesterol, respectively when compared with HDC group (P < 0.05). Serum LDL cholesterol levels in HD-I21 group were not significantly different from HDC group. Serum TG levels in the HD-GG and HD-C38 were decreased by 14.2 and 22.8%, respectively compared with HDC group (P < 0.05). Liver T-CHO and TG levels in the HD-GG, HD-C38, and HD-I21 were reduced significantly compared with the HDC group (P < 0.05). Atherogenic coefficient values of HD-GG, HD-C38, and HD-21 were significantly decreased compared with HDC group (P < 0.05). Serum GPT levels in the HD-GG, HD-C38, and HD-I21 were decreased by 20.6, 10.9, and 20.6%, respectively, vs. the HDC group. Serum GOT levels were not significantly different among the groups. Serum glucose levels were significantly low in HD-GG, HD-C38, and HD-I21 compared with HDC group (P < 0.05). Fecal cholesterol and cholic acid levels were significantly higher in the HD-C38 and HD-GG groups than other groups (P < 0.05). This study suggests that L. plantarum VJC38 exhibits hypocholesterolaemic effect through hydrolysis of conjugated bile acids in the small intestine and excretion of cholesterol in feces. Lactobacillus plantarum VJC38 could be used as a potential cholesterol-lowering probiotic after validation of the hypocholesterolaemic activity in placebo-controlled human clinical trials.     

Calcium antagonists and contractile responses in rat vas deferens and guinea pig ileal smooth muscle.

The effect of depletion of extracellular Ca2+ (Ca2+ext) on the loss of responsiveness of the guinea pig ileal longitudinal muscle (g.p.i.l.m.) and the rat vas deferens (r.v.d.) to K+ and cis-2-methyl-4-dimethylaminomethyl-1,3-dioxolane methiodide (CD), and K+ and noradrenaline (NA), has been examined and compared with the effects of a variety of local anesthetics and calcium antagonists. The results indicate that qualitative similarities are apparent with respect to the dependence of agonist-induced activity on Ca2+ext in both the g.p.i.l.m. and r.v.d. Distinct differences, however, in the Ca2+ translocation processes in these two tissues, in response to the different agonists, can be shown by the use of a variety of 'calcium antagonists' thus indicating that such translocation processes are both tissue and agonist selective. It is thus noted that, contrary to the Ca2+ depletion studies, D 600 and the usually more potent BAY-1040 showed no discrimination of action or potency in their ability to inhibit components of the NA response in the r.v.d. In contrast, D 600 and the more potent BAY-1040 selectively inhibited the tonic component of the K+ response. Treatment with SKF 525A and parethoxycaine (PC) in the g.p.i.l.m. and SKF 525A in the r.v.d. resulted in a nonselective inhibition of responses of the tissues to all stimulants. However, in the r.v.d. PC potentiated NA action, and its methobromide (MeBr) derivative potentiated both NA and K+ action and also, like PC, partially shifted to the left the dose-response curve to Ca2+ in NA-depolarizing Ca-free Tyrode's. The quaternary MeBr and the tertiary 2-chloroethyl (2Cl) derivatives of SKF 525A and PC were selectively more effective against CD- than K+ supported contractile activity in the g.p.i.l.m. and the 2Cl derivatives were more effective against NA than K+ responses in the r.v.d. The 2Cl derivative of PC also was more effective in antagonizing the Ca2+ dose-response curve in high-CD or high-NA than in high-K+ Ca2+-free Tyrode's.