Christo John Frederick Muller
Biomedical Research and Innovation Platform, South Africa
Title: Effects of Rooibos on microbiota dysbiosis: implications for diet-induced metabolic dysfunction
Biography
Biography: Christo John Frederick Muller
Abstract
Recent research indicates that the gut microbiota plays a crucial role in maintaining health or promoting metabolic diseases such as obesity and diabetes. Modulation of the gut microbiome composition by enhancing the polyphenol content of the diet has potentiality in health improvement and even disease prevention. Rooibos (Aspalathus linearis) is known to exhibit such preventive effects against metabolic diseases such as diabetes. We propose that a major factor mediating these effects is through the regulation of gut microbiota by Rooibos polyphenols. We used a high fat and sugar diet-induced non-human diabetic primate model (n=6) to elucidate the effects of Rooibos on GUT microbiota. In the study, we evaluated the effect of 4 weeks of supplementation (90 mg/kg body weight) with a pharmaceutical grade aspalathin-enriched green rooibos extract (Afriplex GRT) containing ca. 12.8% aspalathin, on the gut microbiota of high fat diet-induced diabetic and normal vervet monkeys (Chlorocebus aethiops). Stools collected before and during treatment were analyzed by Microbial DNA qPCR array. The 28-day treatment of the monkeys with GRT extract, improved glucose tolerance, lowered cholesterol, specifically LDL-cholesterol in the blood. In addition, Afriplex GRT significantly affected bacteria deemed to be characteristic of the microbiota phenotype harmful to the metabolism as seen in the shifts between normal monkeys on a maize diet compared to diabetic monkeys on a high fat and sugar diet. The Firmicutes to Bacteroidetes (F/B) ratio, increased in the diabetic monkeys, was reduced by the treatment, that correlated with improved blood glucose and lipid parameters. Key bacterial species increased by the GRT treatment, include: Akkermansia muciniphila, Bacteroides intestinalis, Desulfovibrio piger and Bifidobacterium adolescentis. Supplementation of the diabetic animals Afriplex GRT treatment improved several microbial species relevant to human metabolic diseases in high fat and sugar fed diabetic vervet monkeys.