Marine algae are ecologically important in the food chain and some of have demonstrated wide range of pharmacological properties including antidiabetic activities. This research was aimed to investigate the diabetes-healing effect of a phytochemically active marine alga Padina tenuis. Prior to the in vivo study, both qualitative and quantitative phytochemical status, acute toxicity and antioxidative effects by DPPH radical scavenging assay, ferric reducing assay, superoxide scavenging assay, iron chelating assay were evaluated. The in vivo study was conducted in 10% fructose-fed streptozotocin-induced diabetic rats categorized into five different groups including normal control (NC), diabetic control (DC), reference control (RC), treatments PT-25 (Padina tenuis chloroform extract 25 mg/kg b.w.) and PT-50. Upon routine observation on body weight, food intake, water intake, blood glucose, and oral glucose tolerance (OGT), the animals were sacrificed after three weeks of intervention. Organ weights, serum lipid profile, insulin, alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), creatinine, uric acid and urea were calculated as major indices. The results showed very promising phenolic and flavonoid content, substantial antioxidative effect, non-toxicity in acute level and strong α-amylase inhibition. PT-25 was found to significantly manage the serum AST, ALP, creatinine, uric acid, weekly blood glucose level, glucose tolerance ability as well as kidney and pancreatic weights. Moreover, kidney and pancreatic architecture in histopathological screening were notably improved in the treatment group. β-cells/islet of Langerhans and kidney cells were improved compared to NC animals. The data suggests that Padina tenuis could be very effective as natural sources of antidiabetic agents to modulate pancreatic action and kidney function.
