Anti-hyperglycemic and Anti-hypercholesterolemic Effects of Aloe vera Leaf Gel in Hyperlipidemic Type 2 Diabetic Patients: A Randomized Double-Blind Placebo-Controlled Clinical Trial

Abstract

Diabetes mellitus type 2 with dyslipidemia is a common disease. Previous studies suggest that aloe (Aloe vera L.) leaf gel may positively affect the blood glucose and lipid levels in dyslipidemic type 2 diabetic patients. Thus, in this randomized double-blind placebo-controlled clinical trial with hyperlipidemic (hypercholesterolemic and/or hypertriglyceridemic) type 2 diabetic patients aged 40 to 60 years not using other anti-hyperlipidemic agents and resistant to daily intake of two 5 mg glyburide tablets and two 500 mg metformin tablets, the efficacy and safety of taking aloe gel (one 300 mg capsule every 12 hours for 2 months) combined with the aforementioned drugs in treatment of 30 patients were evaluated and compared with the placebo group (n = 30). The aloe gel lowered the fasting blood glucose, HbA1c, total cholesterol, and LDL levels significantly (p = 0.036, p = 0.036, p = 0.006, and p = 0.004, respectively) without any significant effects on the other blood lipid levels and liver/kidney function tests (p > 0.05) compared with the placebo at the endpoint. No adverse effects were reported. The results suggest that aloe gel may be a safe anti-hyperglycemic and anti-hypercholesterolemic agent for hyperlipidemic type 2 diabetic patients.

Key words

Aloe vera - Liliaceae - diabetes - hyperlipidemia - patient

References

• 1 Campbell R K. Type 2 diabetes: where we are today: an overview of disease burden, current treatments, and treatment strategies.  J Am Pharm Assoc. 2009;  49 S3-S9
• 2 Mudaliar S. New frontiers in the management of type 2 diabetes.  Indian J Med Res. 2007;  125 275-296
• 3 Tomkin G H. Targets for intervention in dyslipidemia in diabetes.  Diabetes Care. 2008;  31 S241-S248
• 4 Derosa G, Sibilla S. Optimizing combination treatment in the management of type 2 diabetes.  Vasc Health Risk Manag. 2007;  3 665-671
• 5 Spratt K A. Managing diabetic dyslipidemia: aggressive approach.  J Am Osteopath Assoc. 2009;  109 S2-S7
• 6 Davidson M H, Toth P P. Comparative effects of lipid-lowering therapies.  Prog Cardiovasc Dis. 2004;  47 73-104
• 7 Krentz A J, Bailey C J. Oral antidiabetic agents: current role in type 2 diabetes mellitus.  Drugs. 2005;  65 385-411
• 8 Huang T H W, Kota B P, Razmovski V, Roufogalis B D. Herbal or natural medicines as modulators of peroxisome proliferator-activated receptors and related nuclear receptors for therapy of metabolic syndrome.  Basic Clin Pharmacol Toxicol. 2005;  96 3-14
• 9 Fugh-Berman A. Herbs and dietary supplements in the prevention and treatment of cardiovascular disease.  Prev Cardiol. 2000;  3 24-32
• 10 Tapsell L C, Hemphill I, Cobiac L, Patch C S, Sullivan D R, Fenech M, Roodenrys S, Keogh J B, Clifton P M, Williams P G, Fazio V A, Inge K E. Health benefits of herbs and spices: the past, the present, the future.  Med J Aust. 2006;  185 S4-S24
• 11 Low Dog T. A reason to season: the therapeutic benefits of spices and culinary herbs.  Explore. 2006;  2 446-449
• 12 Tundis R, Loizzo M R, Menichini F. Natural products as alpha-amylase and alpha-glucosidase inhibitors and their hypoglycemic potential in the treatment of diabetes: an update.  Mini Rev Med Chem. 2010;  10 315-331
• 13 Vogler B K. Aloe vera: a systematic review of its clinical effectiveness.  Br J Gen Pract. 1999;  49 823-828
• 14 Yeh G Y, Eisenberg D M, Kaptchuk T J, Phillips R S. Systematic review of herbs and dietary supplements for glycemic control in diabetes.  Diabet Care. 2003;  26 1277-1294
• 15 Kim K, Kim H, Kwon J, Lee S, Kong H, Im S A, Lee Y H, Lee Y R, Oh S T, Jo T H, Park Y I, Lee C K, Kim K. Hypoglycemic and hypolipidemic effects of processed Aloe vera gel in a mouse model of non-insulin-dependent diabetes mellitus.  Phytomedicine. 2009;  16 856-863
• 16 Rajasekaran S, Ravi K, Sivagnanam K, Subramanian S. Beneficial effects of Aloe vera leaf gel extract on lipid profile status in rats with streptozocin diabetes.  Clin Exp Pharmacol Physiol. 2006;  33 232-237
• 17 Nassiff H A, Fajardo F, Velez F. Effecto del aloe sobre la hiperlipidemia en pacientes refractarios a la dieta.  Rev Cuba Med Gen Integr. 1993;  9 43-51
• 18 Ghannam N, Kingston M, Al-Meshaal I A, Tariq M, Parman N S, Woodhouse N. The antidiabetic activity of aloes: preliminary clinical and experimental observations.  Horm Res. 1986;  24 288-294
• 19 Ajabnoor M A. Effect of aloes on blood glucose levels in normal and alloxan diabetic mice.  J Ethnopharmacol. 1990;  28 215-220
• 20 Koo M L. Aloe vera: antiulcer and antidiabetic effects.  Phytother Res. 1994;  8 461-464
• 21 Yongchaiyudha S, Rungpitarangsi V, Bunyapraphatsara N, Chokechaijaroenporn O. Antidiabetic activity of Aloe vera L. juice. I. Clinical trial in new cases of diabetes mellitus.  Phytomedicine. 1996;  3 241-243
• 22 Oykar A, Can A, Akev N, Baktir G, Sutlupinar N. Effect of Aloe vera leaves on blood glucose level in type I and type II diabetic rat models.  Phytother Res. 2001;  15 157-161
• 23 Bunyapraphatsara N, Yongchaiyudha S, Rungpitarangsi V, Chokechaijaroenporn O. Antidiabetic activity of Aloe vera L. juice. II. Clinical trial in diabetes mellitus patients in combination with glibenclamide.  Phytomedicine. 1996;  3 245-248
• 24 Ramachandra C T, Srinivasa Rao P. Processing of Aloe vera leaf gel: a review.  Am J Agric Biol Sci. 2008;  3 502-510
• 25 Lobo R, Prabhu K S, Shirwaikar A, Ballal M, Balachandran C, Shirwaikar A. A HPTLC densitometric method for the determination of aloeverose in Aloe vera gel.  Fitoterapia. 2010;  81 231-233
• 26 Rajasekaran S, Sivagnanam K, Subramanian S. Mineral contents of Aloe vera leaf gel and their role on streptozocin-induced diabetic rats.  Biol Trace Elem Res. 2005;  108 185-195
• 27 Tanaka M, Misawa E, Ito Y, Habara N, Nomaquchi K, Yamada M, Toida T, Hayasawa H, Takase M, Inagaki M, Hiquchi R. Identification of five phytosterols from Aloe vera gel as anti-diabetic compounds.  Biol Pharm Bull. 2006;  29 1418-1422
• 28 Perez Y Y, Jimenez-Ferrer E, Zamilpa A, Hernandez-Valencia M, Alarcon-Aquilar F J, Tortoriello J, Roman-Ramos R. Effect of a polyphenol-rich extract from Aloe vera gel on experimentally induced insulin resistance in mice.  Am J Chin Med. 2007;  35 1037-1046