Iranian Journal of

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Background: Cardiovascular diseases are the first cause of death in Iran and hypercholesterolemia is one of the most important risk factors. This problem could be partially managed by dietary modifications such as supplementation of diet with dairy products and probiotic bacteria. The aim of this study was to comprise the effect of consuming a probiotic yoghurt and ordinary yoghurt on serum cholesterol levels in mild to moderate hypercholesterolemia.
Methods: This randomized cross-over trial was conducted on 14 healthy subjects aged 40-65 years with total serum cholesterol 200-300 mg/dl. We asked the subjects to avoid consumption of yoghurt for a two-week pre-study period and add 300 g/day of milk to their diet. Then they were randomly allocated to 2 groups to receive either 300 g of ordinary yoghurt (fermented with S.thermophilus and L.bulgaricus) or probiotic yoghurt (fermented with a starter composed of L.acidophilus and B.lactis plus bacteria in ordinary yoghurt) for 6 weeks as substitution for milk. After a wash-out period of 7 weeks, the cross-over was made (those consuming probiotic yoghurt, changed to ordinary yoghurt and vice versa) and the study lasted for another 6 weeks. Anthropometric measurements, a 3-day dietary recall and blood lipid tests were done at the beginning (after a 2-week elimination period of yoghurt from diet) and at the end of each period.
Results: Comparison of weights, BMIs and dietary confounding factors during the period of consuming ordinary yoghurt and probiotic yoghurt, did not show any significant differences. Consumption of probiotic yoghurt in comparison with ordinary yogurt caused a significant decrease in total serum cholesterol (P=0.049). Comparison of other blood lipid criteria did not show any significant differences between these two periods.
Conclusion: Consumption of the yoghurt containing two probiotic bacteria, L.acidophilus and B.lactis, in comparison with ordinary yoghurt causes reduction in total serum cholesterol in mild to moderate hypercholesterolemia.

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Background: Type 2 diabetes is a major metabolic disorder. This study was aimed to evaluate the effect of probiotic soymilk fermented with Bifidobacterium lactis and containing omega-3 on hematologic, oxidative stress, anti-oxidant and inflammatory parameters in type 2 diabetic rats.

Methods: In this experimental manipulation study 65 rats were divided into five groups. Type 2 diabetes was induced by a single injection of streptozotocin and nicotinamide. Normal control (NC) and diabetic control (DC) rats received 1 mL/day of distilled water, and three groups of diabetic rats were administered 1 mL/day of soymilk (SM), fermented soymilk (FSM) and fermented soymilk fortified with omega-3 (FSM+omega-3) products by oral gavage for 28 days. Hematologic, oxidative stress, anti-oxidant and inflammatory parameters were measured at the end of experiment.

Results: At the end of experiment, in all treated diabetic rats compared with the DC group, red blood cell (RBC), hemoglobin (Hb), hematocrit and superoxide dismutase (SOD) concentrations increased significantly (p<0.05), and malondialdehyde (MDA) concentrations reduced significantly (p<0.05). The reduction of MDA and increasing in Hb, RBC, hematocrit and SOD concentrations in the FSM+omega-3 group was more than two other groups. In the FSM+omega-3 group, high sensitivity C-reactive protein (hs-CRP) concentrations compared with the DC and FSM groups were significantly lower (p<0.05).

Conclusion: The experiments suggest that combining soymilk, probiotics and omega-3 may be beneficial for the reducing oxidative-stress in type 2 diabetes.

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Background: The Actinobacteria and Bifidobacterium population, which are the beneficial intestinal bacteria, was compared between pregnant women with gestational diabetes (GDM) and healthy-one, and their relationship with the amount of dietary macronutrients was investigated.
Methods: Fifty pregnant women with GDM, who were identified in the 24-28 weeks of pregnancy, based on the oral glucose tolerance test, and 50 healthy pregnant women with normal results were selected. Stool samples were collected. Bacterial DNA was extracted and 16S rRNA gene amplification was done by qPCR method, using universal bacterial primers. Food information was collected using a food frequency questionnaire.
Results: In total, Actinobacteria phyla (p=0.02) and Bifidobacterium (p=0.001) significantly lower in the pregnant women with GDM than the normoglycemic. Adjusting to the all factors and grouping, age (p=0.02), and education (p=0.04) showed a significant effect on the gut Actinobacteria population. Higher daily calorie intake decreased the intestinal Actinobacteria population by 11.1 times (p=0.01). Dietary carbohydrate and fat showed a positive effect on the gut Actinobacteria (p=0.02 and p=0.003, respectively). Dietary cholesterol showed a negative effect on the Bifidobacterium population (OR= -0.54, p=0.02).
Conclusion: Increase in dietary carbohydrates and fat with an emphasis on mono- and poly-unsaturated fatty acids, decrease in daily calorie intake and cholesterol lead to increase in the Actinobacteria and Bifidobacterium, as the beneficial gut bacteria.