Antihyperglycemic activity of Ficus racemosa bark extract in type 2 diabetic individuals

Diabetes mellitus is a metabolic disorder of the endocrine system with disturbances in carbohydrate, protein, and lipid metabolism characterized by chronic hyperglycemia.1Ficus racemosa (Moraceae), commonly known as “Gular”, is widely used in the treatment of diabetes in India.2 In an earlier report, we demonstrated the antidiabetic activity of F. racemosa bark in streptozotocin-induced diabetic rats.3 Because there are no reports on its clinical efficacy, the present clinical trial evaluated the antihyperglycemic potential of an aqueous extract of F. racemosa bark in type 2 diabetic individuals. The study used a free-living, double-blinded, randomized, placebo-controlled design approved by the Institutional Human Ethical Committee of the University of Mysore (IHEC No. 15-Ph.D/2007-08) in individuals (18 men and 12 women) with documented type 2 diabetes for >1 year and managed with glibenclamide (5 mg/day) for <3 years. To be eligible for inclusion in the study, patients could not have any complications of diabetes, such as diabetic retinopathy, nephropathy, or cardiomyopathy; could not be pregnant; had to have a normal lipid profile; had to be aged between 35 and 50 years; had to be metabolically stable (HbA1c 6.0%–8.5%; fasting plasma glucose [FPG] 6.4–7.5 mmol/L); and must not have been taking insulin, lipid-lowering drugs, or herbs/supplements. Eligible participants were enrolled in the study and provided written informed consent. Aqueous extract of F. racemosa bark (FRAE) was prepared at 70°C, analyzed for various phytochemicals, and standardized using HPLC.4, 5 At the beginning of the study, anthropometric measurements were obtained. Fasting and postprandial blood glucose (PPBG), total cholesterol (TC), triglycerides (TG), and serum insulin levels were determined. A human equivalent dose (HED) of 1.2 g/day FRAE (400 mg × 3 capsules) was established based on in vivo animal studies.3 Identical green, hard gelatin capsules were filled with either FRAE or starch and coded as Capsule A and B. The study subjects were randomly divided into two groups (Groups I and II) using a randomized block design and asked to consume one capsule each before meal. Subjects were asked to report any allergy or discomfort immediately; in addition, subjects attended weekly follow-up visits to detect any adverse effects and clinical symptoms, and to record any significant changes in their diet. After 1 month, the subjects came to the clinic for final body weight measurement and biochemical estimations. Data for FBG, PPBG, insulin, TC, and TG were consolidated and analyzed by one-way anova followed by Tukey’s multiple comparisons test for significant differences using SPSS version 14.0 (SPSS, Chicago, IL, USA). Values were considered significant at P ≤ 0.05. Later, the coding of the capsules was revealed to the principal investigator (F.A.). The body mass index (BMI) of the subjects from both groups were above normal levels and no significant changes were observed in any of the anthropometric measurements and indices during the study period (Table 1). The subjects showed good tolerance to the treatment and no subjects withdrew from the study. A significant reduction (P ≤ 0.05) in both FBG (15%) and PPBG (22%) was observed in the FRAE-treated group compared with the control group after a 1-month supplementation period. These observations were substantiated by serum insulin levels (Fig. 1), wherein a significant increase (P ≤ 0.05) in insulin levels was observed in the FRAE-supplemented group, but no significant (P > 0.05) changes were observed in the control group. Supplementation with FRAE did not bring about any changes in TC or TG levels, because the post-treatment values were similar to initial values and did not differ significantly. Changes in blood glucose and serum insulin levels in the control group and the group treated with an aqueous extract of Ficus racemosa bark (FRAE). Data are the mean ± SD (n = 15). **P ≤ 0.05 compared with initial levels (). (□), final levels; FBG, fasting blood glucose; PPBG, postprandial blood glucose. The findings of the present preliminary clinical trial suggest that F. racemosa bark has a good antihyperglycemic effect in type 2 diabetics by augmenting serum insulin. However, there is a need for long-term studies to fully understand the effects of F. racemosa bark on carbohydrate and lipid metabolism. The authors acknowledge the University Grants Commission, New Delhi, India, for financial assistance (F.31–278/2005). None declared.