PhytoScience - Article

Aloe Vera

 

Historical evidence suggests, that the Aloe Vera plant originated in the warm, dry climates of Africa. However, because the plant is readily adaptable, and because man has been so eager to carry it with him from place to place, it now can be found in many warm lands. In the United States, it is grown commercially in the Rio Grande Valley of Texas, in California and Florida, and in specially-designed greenhouses in Oklahoma.

There are more than 200 species of aloe vera available throughout the world. But out of these species, only four of them are treated to possess therapeutic healing properties such as aloe ferro, aloe saponaria, aloe arborensis and aloe perryi.

Aloe Vera is among the most widely used substances in the U.S. for the treatment of burns and bruises. Additionally, it is used in a plethora of cosmetics, and consumed as a healthful drink. While it has not yet won the full endorsement of the medical community, serious examination continues.

The virtues of the plant have been recorded by many great civilizations, from those of Persia and Egypt in the Middle East, to those of Greece and Italy in Europe, to those of India and the African continent. The plant is widely known in Asia and the Pacific, and is found in the folklore of the Japanese, the Philippines and the Hawaiians. The Spanish used Aloe, and carried it with them to their new world colonies in South America and the Caribbean.

Among the plant's earliest champions were some of the great figures in the history of medicine and medical thought. One of its earliest proponents was the Greek physician Dioscorides. In each age, on each continent, in each culture, Aloe Vera has drawn the attention of the most sophisticated of minds. The first detailed discussion of Aloe's medicinal value is probably that which is found in the Papyrus ebers, an Egyptian document written around B.C.E. 1550. This document gives twelve formulas for mixing Aloe with other agents to treat both internal and external human disorders.

The first milestone in Western man's detailed understanding of medicinal plants is the work of Hippocrites (460B.C.- 375B.C.), the father of modern medicine (doctors today still take the Hippocratic Oath). His Material Medica makes no direct mention of Aloe, but during that same period, the plant, according to Copra's Indigenous Drugs of India, had come into widespread use. Interestingly, Copra writes, "The use of Aloes, the common musabbar, for external application to inflamed painful parts of the body and for causing purgation [internal cleansing] are too well known in India to need any special mention."

Proported Uses

  • Burns
  • Cold sores
  • Colitis
  • Diabetes
  • Dry Skin
  • Inflammation
  • Pain
  • Pruritus

Mechanism of Action

It is presently believed that some of the beneficial effects of aloe result from inhibition of bradykinin by a contained carboxypeptidase. Aloe is also believed to hinder the formation of thromboxane, the activity of which is detrimental to burn wound healing. Laxative effect of aloe juice and aloe latex is caused by anthraquinone glycosides aloin A and B.

Some studies have indicated that aloe vera may have anticancer effects. Emodin, an extract of aloe vera, can inhibit cell proliferation and induce apoptosis in human liver cancer cell lines through p53- and p21-dependent pathway. Acemannan, a carbohydrate fraction derived from aloe vera leaf, can stimulate cytokine production in mouse macrophage cell line. This component also has immunomodulating activities by inducing maturation of dendritic cells.

Another in vitro study has indicated aloeride, a polysaccharide obtained from aloe vera juice, as a potent immunostimulator by increasing NF-kappa B activities. A compound, di(2-ethylhexyl)phthalate (DEHP), isolated from aloe vera can inhibit leukemic cells in vitro..

Adverse Reactions

Reported: (oral): GI upset, nausea and vomiting, occasional rash (dermatitis). Aloe vera supplements have been linked to thyroid dysfunction, acute hepatitis, and perioperative bleeding.
Toxicity: Seizures, potassium loss, and electrolyte abnormalities.

Interactions

Oral
Glyburide: Aloe may increase hypoglycemic effects.
Diuretics: Aloe may have additive hypokalemic effect due to diarrhea if used for a prolonged period.
Digoxin: Aloe may have additive hypokalemic effect due to diarrhea if used for a prolonged period.

Topical
Hydrocortisone: Aloe may increase anti-inflammatory effects.
Sevoflurane:Aloe may have additive antiplatelet effect causing excessive bleeding during surgery.

Clinical Summary

Derived from the leaves of the plant. Topical administration of aloe vera gel is generally safe. It may help reduce radiation-induced skin changes, but clinical trial results are inconsistent. Some of the components extracted from aloe vera have been shown to have anticancer effects in vitro and in animals. However, there is not enough evidence to support the use of aloe vera as an anticancer drug in humans. Limited studies have demonstrated possible efficacy in reducing ulcerative colitis and in glycemic control in diabetic patients. Aloe vera gel should not be confused with aloe juice or aloe latex, both of which contain anthraquinone, a cathartic laxative. Oral and parenteral administration of aloe vera should be avoided due to potential toxicities and lack of clinical efficacy demonstrated in humans. The FDA rules that aloe is not safe as a stimulant laxative. Oral consumption of aloe vera has been linked to thyroid dysfunction, acute hepatitis, and perioperative bleeding. Cancer therapy using injections of acemannan, a mucopolysaccharide derived from aloe vera, resulted in deaths of several patients.

The discovery is brought to market

Forever Living was the first to market Aloe Vera as a food supplement in 1978. Their patented, stabilised Aloe Vera Gel made of 96% pure inner leaf aloe is 'essentially identical' to the fresh gel of the leaf, and it was the first to receive certification by the International Aloe Science Council.

Forever Living's original aloe gel formula; Forever Freedom, is a natural Aloe Vera based supplement drink that helps fight the joint pain and stiffness associated with aging, injury, and the onset of osteoarthritis. Forever Freedom contains a powerful mixture of aloe vera, glucosamine, chondroitin, Methylsulfonylmethane (MSM) and vitamin C. Together, these ingredients help nourish and maintain the cartilage tissue and surrounding fluid that are essential for healthy joint function and mobility.

Chondroitin: Chondroitin can come from natural sources, such as shark or bovine cartilage, or it can be made in a lab. Chondroitin is also known as chondroitin sulfate, chondroitin sulfuric acid, and chonsurid. Chondroitin sulfate is a combination of chondroitin and mineral salt. Chondroitin is available in tablet, capsule, powder, or liquid form and is often taken in combination with other dietary supplements.

Glucosamine: Is a supplement for regenerating cartilage, reducing pain, and improving function in people who struggle with joint pain. Glucosamine is available in tablet, capsule, powder, or liquid form and is often taken in combination with other dietary supplements. Glucosamine has demonstrated anti-inflammatory properties and is reported to regenerate the cartilage that is lost through the normal wear and tear of the body.

Methylsulfonylmethane: (also known as MSM) is a dietary supplement. .MSM is a naturally occurring sulfur compound found in fresh fruits and vegetables, milk, fish, and grains. MSM is therefore found in the normal human diet, but as foods are processed, MSM is destroyed. MSM is an odorless, tasteless, white, water soluble, crystalline solid in its purified form.

Results from a small 12 week pilot clinical trial, published in 2006, showed MSM improved symptoms and function for knee osteoarthritis, but long-term benefits and safety of MSM in managing osteoarthritis were not confirmed. MSM also claims to help constipation, allergies, and even to stop snoring. MSM has not been shown to preserve cartilage, nor halt joint destruction and deformity. Any beneficial effects of MSM last only as long as MSM is taken.

Warning: It appears that glucosamine and chondroitin, in combination or separately, have few side effects. But people with osteoarthritis who have diabetes should talk with a doctor before they take glucosamine, because it is thought that glucosamine may influence blood sugar (glucose). If you are allergic to shellfish, do not take glucosamine unless you have discussed it with your doctor. Glucosamine is made from shellfish covering.

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Disclaimer:
These statements have not been evaluated by the FDA. Any product mentioned is not intended to diagnose, treat, cure or prevent any disease.