Effect of a Polyphenol-Rich Extract from Aloe vera Gel on Experimentally Induced Insulin Resistance in Mice

Abstract

Insulin resistance, which precedes type 2 diabetes mellitus (T2DM), is a widespread pathology associated with the metabolic syndrome, myocardial ischemia, and hypertension. Finding an adequate treatment for this pathology is an important goal in medicine. The purpose of the present research was to investigate the effect of an extract from Aloe vera gel containing a high concentration of polyphenols on experimentally induced insulin resistance in mice. A polyphenol-rich Aloe vera extract (350 mg/kg) with known concentrations of aloin (181.7 mg/g) and aloe-emodin (3.6 mg/g) was administered orally for a period of 4 weeks to insulin resistant ICR mice. Pioglitazone (50 mg/kg) and bi-distilled water were used as positive and negative controls respectively. Body weight, food intake, and plasma concentrations of insulin and glucose were measured and insulin tolerance tests were performed. The insulin resistance value was calculated using the homeostasis model assessment for insulin resistance (HOMA-IR) formula. Results showed that the polyphenol-rich extract from Aloe vera was able to decrease significantly both body weight (p < 0.008) and blood glucose levels (p < 0.005) and to protect animals against unfavorable results on HOMA-IR, which was observed in the negative control group. The highest glucose levels during the insulin tolerance curve test were in the negative control group when compared to the Aloe vera extract and pioglitazone treated mice (p < 0.05). In conclusion, Aloe vera gel could be effective for the control of insulin resistance.

Chemical composition and evaluation of possible alpha glucosidase inhibitory activity of eight Aloe species

“…Since then, the antidiabetic effects of Aloe preparations have been demonstrated in diabetic patients Ajabnoor 1990;Bunyapraphatsara et al, 1996;Yongchaiyudha et al 1996), and in alloxan-or streptozotocin-induced diabetic animal models (Beppu et al, 1993;Rajasekaran et al, 2004Rajasekaran et al, , 2005Rajasekaran et al, , 2006Beppu et al, 2006). A. vera gel was administered to STZ-induced diabetic rats decreased fasting blood glucose levels and improved the levels of the antioxidant enzyme (Nwanjo, 2006); moreover aqueous extract prevented the onset of hyperglycaemia in alloxan-induced diabetic rabbits (Akinmoladun and Akinloye, 2007) ) and aloe-emodin (3.6 mg g -1 ) was administered to insulin resistant mice for 4 weeks improved insulin tolerance and fasting blood glucose levels (Perez et al,2007).…”

Aloe veraGel Extract Attenuates Ethanol-Induced Hepatic Lipid Accumulation by Suppressing the Expression of Lipogenic Genes in Mice

“…A clinical trial has demonstrated the usefulness of Aloe vera for the prophylaxis of radiation-induced dermatitis. Polysaccharides isolated from gel of the Aloe species have various biological activities, previous studies having reported anti-diabetic, 9,10) anti-inflammatory, 11,12) antioxidative, 13) and anti-tumor effects.…”

Protective Effects of Aloe Vera on Superovulated Oocytes and Folliculogenesis in Diabetic Mice

“…Polysaccharides, mannans, anthraquinones, lectins, salicylic acid, urea, nitrogen, cinnamic acid, phenol, sterols and sulphur have been reported as active compounds of Aloevera [8]. Antihyperglycemic activity of this plant has well confirmed in STZ or Alloxan induced diabetic animals [3,9]. Free radicals generated in diabetes conditions could adversely affect reproductive organs and tissues.…”