ANTI-INFLAMMATORY EFFECTS OF ROBUSTA COFFEE ON IL-6 AND IL-18 LEVELS IN DIABETIC RATS

Abstract

Persistent low-grade inflammation accompanies diabetes mellitus and drives the disease forward, largely because pro-inflammatory mediators such as interleukin-6 (IL-6) and interleukin-18 (IL-18) are produced in excess. Because robusta coffee carries a substantial load of chlorogenic acid together with other bioactive constituents, it has been proposed as an agent capable of dampening the inflammation that accompanies diabetes. The objective of this work was to determine how robusta coffee affects circulating IL-6 and IL-18 in a diabetic rat model. Twenty-eight male Wistar rats were allocated at random into four arms in an experimental design: an untreated diabetic control, a metformin-treated arm, and two arms receiving 1 mL and 2 mL of robusta coffee, respectively. The diabetic state was established through streptozotocin and nicotinamide administration, and cytokine concentrations in serum were quantified by ELISA. Relative to untreated diabetic animals, both cytokines were markedly lower after coffee administration, with the lowest levels observed in animals given 2 mL. The two cytokines showed a very strong positive correlation. Taken together, the data point to robusta coffee as a candidate natural adjunct for reducing systemic inflammation in diabetes, although the underlying mechanisms require further confirmation.