This Is AuburnElectronic Theses and Dissertations

Antioxidant, anti-inflammatory and anti-hyperglycemic properties of Tridax procumbens in lowering cardio-metabolic risk factors

Date

2014-10-06

Author

Desai, Gauri

Type of Degree

dissertation

Department

Nutrition and Food Science

Abstract

Tridax procumbens L. has traditionally been used in India and Africa for the management of diabetes and inflammation. Phytochemical characterization has revealed presence of carotenoids, saponins, tannins, phenolics and flavonoids. Animal studies have shown that T. procumbens exerts antioxidant, anti-hyperglycemic, anti-inflammatory, anti-hypertensive, and anti-atherogenic effects. Therefore, we sought to characterize potential mechanisms mediating anti-hyperglycemic and anti-inflammatory effects and hypothesized that T. procumbens supplementation may lower cardiovascular risk factors. An asava (a hydro-alcoholic fermented extract), was prepared according to Ayurveda guidelines, using Woodfordia fruticosa L. Kurz flowers. Chemical and microbial analyses indicated the presence of phenolics, flavonoids, and carotenoids, and absence of microbial contamination, aflatoxins, heavy metals, and pesticide residues. T. procumbens asava demonstrated strong total antioxidant capacity, H2O2 scavenging activity, and inhibition of lipid peroxidation. A 4-week pilot study to evaluate blood glucose lowering effects demonstrated that T. procumbens asava supplementation lowered both fasting (decreased by 11% in men and 20% in women) and post-prandial blood glucose (decreased by 26% in men and 29% in women) in individuals with type 2 diabetes. In H4IIE rat hepatoma cells, both T. procumbens and W. fruticosa activated AMPK (AMP-activated protein kinase), and inhibited dexamethasone-induced gluconeogenic gene expression and hepatic glucose production. The anti-inflammatory effect of T. procumbens and W. fruticosa was mediated through inhibition of NFκB activation and NFκB transcriptional activity. A randomized, double-blind, placebo-controlled trial was conducted to evaluate cardio-protective effects of T. procumbens. Seventy five individuals with type 2 diabetes were randomized to one of three groups that received either T. procumbens asava, W. fruiticosa asava, or placebo for 4 months. T. procumbens significantly lowered systolic blood pressure, total cholesterol, and LDL-cholesterol compared to placebo. No significant changes were observed in BMI, waist circumference, diastolic blood pressure, blood glucose, HbA1c, triglycerides, ALT, AST, urea or creatinine. At the end of the study period, a higher prevalence of individuals with HbA1c < 7.5%, was observed in T. procumbens group compared to placebo. No adverse effects were reported. Taken together, T. procumbens exerts strong antioxidant, anti-hyperglycemic and anti-inflammatory effects in vitro and in intact cells. T. procumbens asava supplementation appeared to lower systolic blood pressure, total and LDL-cholesterol, with modest effects on HbA1c.