Black mulberry (Morus nigra L.) prevents deleterious effects of excess glucose in obese C. elegans decreasing lipofuscin accumulation and ROS production

Black mulberries have been traditionally used as antidiabetic agents and are a source of nutrients and phenolic compounds, particularly anthocyanins. The objective of this work is to determine if Morus nigra berries could prevent metabolic and obesity-related disorders using in vitro systems and in vivo alternative models such as C. elegans. An aqueous solvent-free extract from Morus nigra fruits rich in phenolic compounds like chlorogenic acid, hyperoside, rutin and cyanidin 3-glucoside was evaluated in the C. elegans obese model subjected to high glucose concentrations evaluating different parameters such as lipid droplets, lipofuscin accumulation and ROS production. The capacity of the extract to inhibit advance glycation end products and free radicals as well as pancreatic lipase and α-amylase was also evaluated in vitro. The black mulberry extract showed a significant capacity to inhibit the accumulation of lipid droplets, reducing by 50.40 % the fat deposits. The extract was able to reverse the deleterious effects of excess glucose in C. elegans enhancing stress resistance, preventing the accumulation of lipofuscin, and decreasing the ROS production. The anti-glycation and antioxidant effects in vitro were higher than the reference substances aminoguanidine and quercetin respectively. Morus nigra was also able to inhibit the pancreatic enzymes α-amylase and lipase and could be considered an interesting traditional food ingredient in the prevention of certain metabolic diseases.