Effects of Digitaria exilis (fonio) on glucose metabolism and inflammatory cytokines in KK/HIJ diabetic male mice

Digitaria exilis , a wild cereal consumed in West Africa, is rich in chromium, beta‐glucans and sulfur amino acids, factors that modulate inflammation. Fonio is thought to have anti‐diabetic properties, but the mechanism is unknown. Considering that one of the characteristics of diabetes is inflammation, we investigated whether its beneficial effects might be regulated through inflammation. Four‐week old KK/HIJ transgenic male mice were fed either the AIN 93 diet or the same diet fortified with 30% fonio or rice flour (n=20). Ten mice/diet were sacrificed after 3 or 4 months. Glucose and insulin tolerance tests (GTT & ITT) were studied by standard techniques. Spleen cells (2 x 10 6 /ml) were activated with 2.5 μg/ml Con A or LPS for 48 h, and cytokines were measured in the supernatant and plasma by ELISA. After 4 months, results showed that ITT test was different among groups. Blood glucose levels were lower in mice fed fonio than in those fed the other two diets (p<0.01). Fonio non‐significantly reduced GTT. Serum TNF‐alpha was lower in mice fed fonio than in those fed baseline and rice‐fortified diets (p<0.05). Serum IL‐6 of mice fed fonio was not different from those fed baseline diet; but it was lower than those fed rice diet (P<0.01). Fonio and rice did not significantly affect in vitro cytokine secretion. Data suggest that fonio may modulate diabetes severity by reducing inflammatory cytokines. (Supported by Oklahoma Center for Advancement of Science and Technology and Oklahoma State University)