Momordica charantia, also known as Bitter Melon or bitter gourd is a member of Cucurbitaceae family. Bitter Melon extracts (primarily from fruits) are used in a variety of diseases including diabetes, dyslipidemia, microbial infections, and potentially as a cytotoxic agent for certain types of cancer (ref 1). Bitter Melon is useful for diabetics as a blood sugar lowering agent, an anti-oxidant that can cut down on hyperglycemic damage and as an agent that can help the body utilize insulin. The following guide is a summation of much of the research currently available for this Diabetic Herb.
Bitter Melon extracts possess anti-diabetic, hepato-renal protective and hypolipidemic effect in diabetic rats. Thus, Bitter Melon is alternative therapy that has primarily been used for lowering blood glucose levels in patients with diabetes mellitus. Beneficial effects were observed in Glycosaminoglycans (GAGs) metabolism during diabetes and it was postulated due to presence of dietary fibres present in bitter gourd and spent turmeric and presence of bioactive compounds in one or both of them (ref 4 ).
Experimental evidence was provided by research studies on dried bitter gourd powder in the diet at 10% level improved diabetic status signifying its beneficial effects during diabetes (ref 5). During diabetes structural and functional changes have been reported in alimentary tract and renal cortex which increases absorption of intestinal glucose and alternations in the activities of brush border dissacharidases. Feeding bitter gourd to diabetic rats showed positive influence on intestinal and renal dissacharidases making diabetic animals more tolerant to hyperglycermia (ref 6). Bitter Melon seeds extract- exerted rapid protective effects against lipid peroxidation by scavenging of free radicals thereby reducing the risk of diabetic complications (ref 7).
Memordica fruit extract and Sodium orthovandate exhibit hypolipedmic as well as hypoglycemic effect in diabetic rats (ref 8). According to research studies bitter melon has the potential to down-regulate insulin as well as preventative value with respect to a wide range of disorders. Parallels have been drawn between action of metformin and bitter melon including analogous effects on the hepatic activity certain enzymes of glucose-metabolism, increased expression of GLU4 in the plasma membrane of skeletal muscle and a tendency to prevent weight gain.
Aqueous extract powder of Bitter Melon, an edible vegetable, appears to be a safe alternative to reducing blood glucose. The aqueous extract powder of fresh unripe whole fruits was found to reduce fasting blood sugar by 48%, an effect comparable to that of Glibenclamide, a synthetic drug (ref 11).
The pharmacology, clinical efficiency, adverse effects, drug interactions of bitter melon have been studied in clinical trials (ref 12). Studies have been done to review the efficacy and safety of natural products commonly used for diabetes. Based on available evidence natural products like fenugreek, bitter melon, ginseng etc. can lower blood sugar in diabetic patients (ref 13).
Results of study on diabetic animals, suggests that changes in hepatic phase I and phase II
Drug metabolizing enzyme activities in STZ-induced diabetic animals may be associated with the altered expression of different CYP (Cytochrome 450) and GST (Glutathione-S-transferase) drug metabolizing isoenzymes.
It has been reported that ethyl acetate extract of bitter melon activated peroxisome proliferator receptors (PPRAs) alpha and gamma. PPRAs are ligand-dependent transcription factors that belong to the steroid hormone nuclear receptor family and control lipid and glucose homeostatis in the body (ref 2). Results of research study suggest that Bitter Melon juice and alcohol extracts caused a significant decrease in serum urea, creatinine, ALT, AST, AP, cholesterol and triglyceride levels (ref 3).
- Momordica charantia (bitter melon) – Monograph. Altern Med Rev. 2007 Dec; 12(4):360-3.
- Fractionation and identification of 9c, 11t, 13t-conjugated linolenic acid as an activator of PPARalpha in bitter gourd (Momordica charantia L.). J Biomed Sci. 2006 Nov; 13(6):763-72. Epub 2006 Sep 6.
- Some toxicological studies of Momordica charantia L. on albino rats in normal and alloxan diabetic rats. J Ethnopharmacol. 2006 Nov 24; 108(2):236-42. Epub 2006 May 26.
- Effect of bitter gourd and spent turmeric on constituents of glycosaminoglycans in different tissues in streptozotocin induced diabetic rats. Mol Cell Biochem. 2006 Jun; 286(1-2):53-8. Epub 2006 Mar 11.
- Effect of bitter gourd (Momordica charantia) on glycaemic status in streptozotocin induced diabetic rats. Plant Foods Hum Nutr. 2005 Sep;60(3):109-12.
- Bitter gourd (Momordica charantia) modulates activities of intestinal and renal disaccharidases in streptozotocin-induced diabetic rats. Mol Nutr Food Res. 2005 Aug; 49(8):791-6.
- Antioxidant properties of Momordica Charantia (bitter gourd) seeds on Streptozotocin induced diabetic rats. Asia Pac J Clin Nutr. 2005; 14(2):153-8.
- Combined treatment of sodium orthovanadate and Momordica charantia fruit extract prevents alterations in lipid profile and lipogenic enzymes in alloxan diabetic rats. Mol Cell Biochem. 2005 Jan; 268(1-2):111-20.
- Does bitter melon contain an activator of AMP-activated kinase? Med Hypotheses. 2004; 63(2):340-3.
- Evaluation of the efficacy of bitter gourd (Momordica charantia) as an oral hypoglycemic agent–a randomized controlled clinical trial. Indian J Physiol Pharmacol. 2003 Jul; 47(3):363-5.
- Antihyperglycemic effects of three extracts from Momordica charantia. J Ethnopharmacol. 2003 Sep; 88(1):107-11.
- Bitter melon (Momordica charantia): a review of efficacy and safety. Am J Health Syst Pharm. 2003 Feb 15; 60(4):356-9.
- Natural products used for diabetes. J Am Pharm Assoc (Wash). 2002 Mar-Apr; 42(2):217-26.
- Effect of bitter melon (Momordica charantia) fruit juice on the hepatic cytochrome P450-dependent monooxygenases and glutathione S-transferases in streptozotocin-induced diabetic rats. Biochem Pharmacol. 1996 Nov 22; 52(10):1639-42.