The positive influence of Aloe vera, a tropical cactus, on the healing of full-thickness wounds in diabetic rats is reported. Full-thickness excision/incision wounds were created on the back of rats, and treated either by topical application on the wound surface or by oral administration of the Aloe vera gel to the rat. Wound granulation tissues were removed on various days and the collagen, hexosamine, total protein and DNA contents were determined, in addition to the rates of wound contraction and period of epithelialization. Measurements of tensile strength were made on treated/untreated incision wounds. The results indicated that Aloe vera treatment of wounds in diabetic rats may enhance the process of wound healing by influencing phases such as inflammation, fibroplasia, collagen synthesis and maturation, and wound contraction. These effects may be due to the reported hypoglycemic effects of the aloe gel.

To treat diabetes mellitus by conducting separate experiments on non-diabetic (ND), type I (IDDM) and type II (NIDDM) diabetic rats

Effect of Aloe vera leaves on blood glucose level in type I and type II diabetic rat models

Department of Pharmacology, Faculty of Pharmacy, University of Istanbul, 34452 Universite, Istanbul, Turkey

Aloe vera (L.) Burm. fil. (= A. barbadensis Miller) (Liliaceae) is native to North Africa and also cultivated in Turkey. Aloes have long been used all over the world for their various medicinal properties. In the past 15 years, there have been controversial reports on the hypoglycaemic activity of Aloe species, probably due to differences in the parts of the plant used or to the model of diabetes chosen. In this study, separate experiments on three main groups of rats, namely, non-diabetic (ND), type I (IDDM) and type II (NIDDM) diabetic rats were carried out. A. vera leaf pulp and gel extracts were ineffective on lowering the blood sugar level of ND rats. A. vera leaf pulp extract showed hypoglycaemic activity on IDDM and NIDDM rats, the effectiveness being enhanced for type II diabetes in comparison with glibenclamide. On the contrary, A. vera leaf gel extract showed hyperglycaemic activity on NIDDM rats. It may therefore be concluded that the pulps of Aloe vera leaves devoid of the gel could be useful in the treatment of non-insulin dependent diabetes mellitus.

To study the effects of Aloe vera on gap junctional intercellular communication (GJIC) and proliferation of human skin fibroblasts

Effects of Aloe vera on Gap Junctional Intercellular Communication and Proliferation of Human Diabetic and Nondiabetic Skin Fibroblasts

¹Department of Surgery, School of Medicine, University of North Dakota, Grand Forks, ND; and Plastic Surgery Institute, Fargo, ND; ²Department of Animal and Range Sciences and Cell Biology Center, North Dakota State University, Fargo, ND

Objective: To evaluate the effects of Aloe vera on gap junctional intercellular communication (GJIC) and proliferation of human skin fibroblasts in the presence or absence of basic fibroblast growth factor (FGF-2). Design: In vitro study using human type II diabetic and nondiabetic skin fibroblast cell lines. Setting and subjects: Diabetic (n = 4) and nondiabetic (n = 4) human skin fibroblast cell lines were purchased from Coriell Institute for Medical Research (Camden, NJ). The cells were cultured with or without Aloe vera extract in increasing concentrations (0%, 0.625%, 1.25%, 2.5%, 5%, 10%, and 20%; v/v) in culture medium and with or without FGF-2 (30 ng/mL). Measurements: GJIC was evaluated after 48-hour incubation with treatments by laser cytometry. Cells were counted after 72-hour incubation with treatments by using a Coulter counter. Results: The rate of GJIC was greater (p < 0.01) for diabetic than for nondiabetic fibroblasts (3.5 ± 0.1 versus 3.0 ± 0.1% per minute during the first 4 minutes after photobleaching). GJIC was increased ( p < 0.05) for diabetic fibroblasts in the presence of 2.5% and 5% of Aloe vera extract (4.2 ± 0.1 and 4.0 ± 0.2 versus 3.5 ± 0.1% per minute for control, respectively). FGF-2 stimulated (p < 0.01) GJIC for diabetic (4.0 ± 0.1 versus 3.5 ± 0.1% per minute for control) and nondiabetic (3.5 ± 0.1 versus 3.0 ± 0.1% per minute for control) fibroblasts. Aloe vera extract did not affect GJIC of nondiabetic fibroblast cultured without FGF-2. However, Aloe vera extract decreased (p < 0.05) FGF-2 stimulatory effects on GJIC of diabetic and nondiabetic fibroblasts. Proliferation of diabetic fibroblasts was increased (p < 0.05) by 1.25% and 2.5% Aloe vera extract in medium. Proliferation of nondiabetic fibroblasts was not affected by Aloe vera extract. FGF-2 increased (p < 0.05) proliferation of nondiabetic fibroblasts and FGF-2 did not affect proliferation of diabetic fibroblasts. Aloe vera extract decreased (p < 0.05) FGF-2 stimulatory effects on proliferation of nondiabetic fibroblasts. Conclusions: These data demonstrate that Aloe vera has the ability to stimulate GJIC and proliferation of human skin fibroblasts in diabetes mellitus. Furthermore, these results indicate that Aloe vera contains a compound(s) that neutralizes, binds with FGF-2 receptor, or otherwise alters signaling pathways for FGF-2. By affecting both GJIC and proliferation of diabetic fibroblasts, Aloe vera may improve wound healing in diabetes mellitus.

To evaluate the presence of hypoglycemic activity in the alcoholic extract of Aloe vera gel

Hypoglycemic Effect of Aloe vera Gel on Streptozotocin-Induced Diabetes in Experimental Rats

Department of Biochemistry & Molecular Biology, University of Madras, Chennai, India

In the present study an attempt has been made to evaluate the presence of hypoglycemic activity in the alcoholic extract of Aloe vera gel. Effects of oral administration of A. vera extract at a concentration of 200 and 300 mg/kg of body weight on (a) normal fasted rats, (b) oral glucose-loaded rats, and (c) streptozotocin-induced diabetic rats have been studied. A. vera extract maintain the glucose homeostasis by controlling the carbohydrate metabolizing enzymes.

Withania somnifera and Aloe vera

Susceptibility of hippocampus and cerebral cortex to oxidative damage in streptozotocin treated mice: prevention by extracts of Withania somnifera and Aloe vera

M.S. Parihar, Madhulika Chaudhary, Rajani Shetty, Taruna Hemnani

Biochemistry Division, Faculty of Life Science, School of Studies in Zoology, Vikram University, Ujjain 456 010, India

To study the effect of antidiabetic activity of aloes

The antidiabetic activity of aloes: preliminary clinical and experimental observations

Not available

The dried sap of the aloe plant (aloes) is one of several traditional remedies used for diabetes in the Arabian peninsula. Its ability to lower the blood glucose was studied in 5 patients with non-insulin-dependent diabetes and in Swiss albino mice made diabetic using alloxan. During the ingestion of aloes, half a teaspoonful daily for 4-14 weeks, the fasting serum glucose level fell in every patient from a mean of 273 +/- 25 (SE) to 151 +/- 23 mg/dl (p less than 0.05) with no change in body weight. In normal mice, both glibenclamide (10 mg/kg twice daily) and aloes (500 mg/kg twice daily) induced hypoglycaemia after 5 days, 71 +/- 6.2 and 91 +/- 7.6 mg/dl, respectively, versus 130 +/- 7 mg/dl in control animals (p less than 0.01); only glibenclamide was effective after 3 days. In the diabetic mice, fasting plasma glucose was significantly reduced by glibenclamide and aloes after 3 days. Thereafter only aloes was effective and by day 7 the plasma glucose was 394 +/- 22.0 versus 646 +/- 35.9 mg/dl, in the controls and 726 +/- 30.9 mg/dl in the glibenclamide treated group (p less than 0.01). We conclude that aloes contains a hypoglycaemic agent which lowers the blood glucose by as yet unknown mechanisms.

To study the effect of Aloe vera on wounds, edema, and pain in diabetes

Title

Aloe vera. A natural approach for treating wounds, edema, and pain in diabetes

Authors

Address

Not available

Not available

To study the anti-inflammatory activity in diabetes

Aloe vera and gibberellin. Anti-inflammatory activity in diabetes

Not available

Aloe vera inhibits inflammation and adjuvant-induced arthritis. The authors' laboratory has shown that A. vera improves wound healing, which suggests that it does not act like an adrenal steroid. Diabetic animals were used in this study because of their poor wound healing and anti-inflammatory capabilities. The anti-inflammatory activity of A. vera and gibberellin was measured in streptozotocin-induced diabetic mice by measuring the inhibition of polymorphonuclear leukocyte infiltration into a site of gelatin-induced inflammation over a dose range of 2 to 100 mg/kg. Both Aloe and gibberellin similarly inhibited inflammation in a dose-response manner. These data tend to suggest that gibberellin or a gibberellin-like substance is an active anti-inflammatory component in A. vera.

To study the hypoglycemic effect of Aloe barbadensis

Effect of aloes on blood glucose levels in normal and alloxan diabetic mice

Department of Clinical Biochemistry, College of Medicine and Allied Sciences, King Abdulaziz University, Jeddah, Saudi Arabia

The acute and chronic effects of the exudate of Aloe barbadensis leaves and its bitter principle were studied on plasma glucose levels of alloxan-diabetic mice. Aloes was administered orally, 500 mg/kg, and the bitter principle was administered intraperitoneally, 5 mg/kg. The hypoglycemic effect of a single oral dose of aloes on serum glucose level was insignificant whereas that of the bitter principle was very highly significant and extended over a period of 24 h with maximum hypoglycemia observed at +8 h. In chronic studies, aloes was administered twice daily and the bitter principle was administered once a day for 4 days. The maximum reduction in plasma glucose level was observed at the 5th day in both cases. The hypoglycemic effect of aloes and its bitter principle may be mediated through stimulating synthesis and/or release of insulin from thebeta-cells of Langerhans.