Obiajulu Christian Ezeigwe - Department of Applied Biochemistry, Faculty of Biosciences, Nnamdi Azikiwe University Awka, Anambra State, Nigeria
Daniel Nnaemeka Onwusulu - Department of Obstetrics and Gynaecology, Faculty of Medicine, College of Health Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria
Chukwuemeka Steve Adindu - Department of Applied Biochemistry, Faculty of Biosciences, Nnamdi Azikiwe University Awka, Anambra State, Nigeria
Chukwudi Onyeaghana Okani - Department of Histopathology, Chukwuemeka Odumegwu Ojukwu University, Awka Campus, Anambra State, Nigeria

Introduction: Diabetes mellitus is a common global cause of sudden unpredictable death if undiagnosed and untreated. Costus afer (Costaceae) is a tropical plant with quite a lot of pharmacological properties. This study investigated the prophylactic and antidiabetic properties of ethyl acetate fraction of C. afer in streptozotocin-induced diabetic rats. Methods: Acute toxicity (LD۵۰) test was done using Lorke’s method. Haematological indices were determined using haematology autoanalyser. The biochemical assays were done using standard diagnostic methods. Results: The lethal dose was ۳۸۰۷.۹ mg/kg. There was a significant reduction (P < ۰.۰۵) in the fasting blood glucose concentration from week one to week four in the group that was pre-treated and later post-treated with ۲۰۰ mg/kg body weight (bw) of the ethyl acetate fraction of C. afer leaves compared with the untreated diabetic control. The result of the hematological parameters revealed a significant increase (P < ۰.۰۵) in the hemoglobin, packed cell volume (PCV), and platelet count of the group pretreated and treated with ۲۰۰ mg/kg of the fraction compared with the untreated diabetic control. The result of the biochemical assays revealed a far much better recovery from the disruptions caused by the induction of experimental diabetes as seen in the groups that were initially pretreated with ۱۰۰ and ۲۰۰ mg/kg before the induction of diabetes compared with the groups treated with the same dose but without pretreatment. Conclusion: C. afer might be used for the prevention and management of diabetes mellitus. Its safety is evidenced by its effects on the hematological and biochemical indices.

Diabetes, Prophylactic effect, Acute toxicity, Lethal dose, Haemoglobin