Anti-diabetic Activity of Ayurveda Herbs – A Review

Dr Chakrapany Sharma
Professor and HoD
Department of Dravyaguna Vigyan
(Medicinal Plants Science)
Dr S R Rajasthan Ayurveda University
Jodhpur, Rajasthan, India

Dr Arun Dadhich
Asst. Professor
Deptt of Rog and Vikriti Vigyan
Dr S R Rajasthan Ayurveda University
Jodhpur, Rajasthan, India

Dr. Harish Kumar Singhal
Assistant Professor
Department of Kaumarbhritya
Dr S R Rajasthan Ayurveda University
Jodhpur, Rajasthan, India
Email. drharish_md@yahoo.co.in

Abstract

Ayurveda is an ancient system of health and life, originated in India. A couple of well documented texts are available containing information regarding the fitness, longevity of life and for the treatment of various diseases. Diabetes mellitus (DM) is the commonest endocrine disorder that affects more than 100 million people worldwide (6% of the population)(WHO/Acadia, 1992). It is caused by the deficiency or ineffective production of insulin by pancreas which results in increase or decrease in concentrations of glucose in the blood. It is found to damage many of the body systems, particularly the blood vessels and nerves. Many herbal plants with hypoglycemic prop-erties are known from across the world. Ayurveda refers the term “Madhumeha” for the Diabetes. Diabetes is an important human ailment afflicting many from various walks of life in different countries. In India it is proving to be a major health problem, especially in the urban areas. Major texts of Ayurveda the Charaka Samhita, Sushruta Samhita and Ashtang Sangraha refers anti diabetic herbs.

Although there are a number of hypoglycemic agents available, but they don’t span a total control over the blood glucose levels over long periods of time and are accompanied by many side effects. Along with it, there are various approaches to reduce the ill effects of diabetes and its secondary complications, herbal formulations are preferred due to lesser side effects and low cost. Researches conducted in the last few decades on plants, mentioned in ancient literature or used traditionally for diabetes, have shown anti-diabetic property.Trigonella foenumgraecum, Momor-dica charantia, Tinospora cordifolia, Enicostema littorae, Gymnema sylvestre, Azadirachta indica, Syzigium cumini are some of the most effective and the most commonly studied Indian plants in relation to diabetes. Based on possible mechanism of action, antidiabetic plants reported in Ayurveda have been classified and described in this article.

One of the etiologic factors implicated in the development of diabetes and its complications is the damage induced by free radicals and hence an anti-diabetic compound with antioxidant properties would be more beneficial. Therefore information on antioxidant effects of these anti diabetic medicinal plants is also included. Further to, attempt has been made to explore the scientific evidences with the available references which may prove that the ancient Acharyas were very advance for the uses of herbs for the health care.

Keywords: Ayurveda, Diabetes mellitus; hypoglycemic; ant diabetic plants; Active chemical constituents; pharmacognosy. Havisha, Dakshaprajapati

Introduction

The word diabetes was coined by the Greek physician Aerestaeus in the first century A.D. In the 17th century, Willis observed that the urine of diabetics as wonderfully sweet as if imbued with honey or sugar. The presence of sugar in the urine of diabetics was demonstrated by Dobson in 1755 (Satoskar, 1999).

Diabetes mellitus has been known since ages and the sweetness of diabetic urine has been mentioned in Ayurveda by Charaka and Sushruta. Ayurveda named the Diabetes as the term Madhumeha under the chapter of 20 types of Prameha, means “Presence of Sugar in Urine”. (Charak Samhita)

In the last few years there has been an exponential growth in the field of herbal medicine and these drugs are gaining popularity both in developing and developed countries because of their natural origin and less side effects. Many traditional & complementary medicines in use are derived from medicinal plants, minerals and organic matter. (Grover J.K, et all. 2002) A number of medicinal plants refers Ayurveda from the time immemorial named Rasayana, whichare said good for the longevity of life and to develop immunity of human body. (Scartezzini P., Sproni E, 2000 ) In Indian systems of medicine most practitioners formulate and dispense their own recipes. The World Health Organization (WHO) has listed 21,000 plants, which are used for medicinal purposes around the world. Among these 2500 species are in India, out of which 150 species are used commercially on a fairly large scale. India is the largest producer of medicinal herbs and is called as botanical garden of the world. (Seth S.D., Sharma B., 2004)

Diabetes mellitus

Diabetes is a chronic disorder of carbohydrate, fat and protein metabolism characterized by increased fasting and post prandial blood sugar levels. The global prevalence of diabetes is estimated to increase, from 4% in 1995 to 5.4% by the year 2025. WHO has predicted that the major burden will occur in developing countries? Studies conducted in India in the last decade have highlighted that not only is the prevalence of diabetes high but also that it is increasing rapidly in the urban population. WHO has predicted that the major burden will occur in developing countries? Studies conducted in India in the last decade have highlighted that not only is the prevalence of diabetes high but also that it is increasing rapidly in the urban population. It is estimated that there are approximately 33 million adults with diabetes in India. This number is likely to increase to 57.2 million by the year 2025.

Diabetes mellitus is a complex metabolic disorder resulting from either insulin insufficiency or insulin dysfunction. (Ramachandran A., Snehalatha C., Viswanathan V, 2002 ) Type I diabetes (insulin dependent) is caused due to insulin insufficiency because of lack of functional beta cells. Patients suffering from this are therefore totally dependent on exogenous source of insulin while patients suffering from Type II diabetes (insulin independent) are unable to respond to insulin and can be treated with dietary changes, exercise and medication. Type II diabetes is the more common form of diabetes constituting 90% of the diabetic population.

Symptoms for both diabetic conditions may include: (a) high levels of sugar in the blood; (b) unusual thirst; (c) frequent urination; (d) extreme hunger and loss of weight; (e) blurred vision; (vi) nausea and vomiting; (f) extreme weakness and tiredness; (g) irritability, mood changes etc. Though patho-physiology of diabetes remains to be fully understood, experimental evidences suggest the involvement of free radicals in the pathogenesis of diabetes and more importantly in the development of diabetic complications. (Oberlay L.W. & Lipinski B., 2001)

For the development of diabetic complications, the abnormalities produced in lipids and proteins are the major etiologic factors. In diabetic patients, extra-cellular and long lived proteins, such as elastin, laminin, collagen are the major targets of free radicals. These proteins are modified to form glycoproteins due to hyperglycemia. The modification of these proteins present in tissues such as lens, vascular wall and basement membranes are associated with the development of complications of diabetes such as cataracts, microangiopathy, atherosclerosis and nephropathy.
(Glugliano D., Ceriello A., 1996 )

There are also multiple abnormalities of lipoprotein metabolism in very low density lipoprotein (VLDL), low density lipoprotein (LDL), and high density lipoprotein (HDL) in diabetes. Lipid peroxidation is enhanced due to increased oxidative stress in diabetic condition. Apart from this, advanced glycation end products (AGEs) are formed by non-enzymatic glycosylation of proteins. AGEs tend to accumulate on long-lived molecules in tissues and generate abnormalities in cell and tissue functions. (Brownlee M. 1996, Elgawish A., Glomb, et all, 1999)

In addition, AGEs also contribute to increased vascular permeability in both micro and macrovascular structures by binding to specific macrophage receptors. This results in formation of free radicals and endothelial dysfunction. AGEs are also formed on nucleic acids and histones and may cause mutations and altered gene expression. As diabetes is a multifactor disease leading to several complications, and therefore demands a multiple therapeutic approach. Patients of diabetes either do not make enough insulin or their cells do not respond to insulin. In case of total lack of insulin, patients are given insulin injections. Whereas in case of those where cells do not respond to insulin many different drugs are developed taking into consideration possible disturbances in carbohydrate-metabolism. Although several therapies are in use for treatment, there are certain limitations due to high cost and side effects such as development of hypoglycemia, weight gain, gastrointestinal disturbances, liver toxicity etc. (Dey L., Anoja S.A., Yuan C-S, 2002)

Based on recent advances and involvement of oxidative stress in complicating diabetes mellitus, efforts are on to find suitable anti-diabetic and antioxidant therapy. Medicinal plants are being looked up once again for the treatment of diabetes. Many conventional drugs have been derived from prototypic molecules in medicinal plants. The World Health Organization Expert Committee on diabetes has recommended that traditional medicinal herbs be further investigated, including Ayurveda, Chinese system of medicine, etc. Major hindrance in amalgamation of herbal medicine in modern medical practices is lack of scientific and clinical data proving their efficacy and safety. There is a need for conducting clinical research in herbal drugs, developing simple bioassays for biological standardization, pharmacological and toxicological evaluation, and developing various animal models for toxicity and safety evaluation. It is also important to establish the active component/s from these plant extracts.

Although from a clinical standpoint this may be true, our increasing knowledge of the pathophysiology of the syndrome, together with the mechanisms of long- term complications, has placed diabetes research at the frontier of immunology and molecular biology (Debra-Haire-Joshu, 1991).

There are different approaches to the treatment of diabetes, like insulin treatment in type 1 diabetes: Sul-phonylureas, which release insulin from pancreas by blocking the ATP-sensitive potassium channels (Aslam, 2002); Biguanides, which decrease the insulin resis-tance; Thizaolidinediones, which increase the insulin sensitivity; alpha-glucodase inhibitors like acarbose, which decrease glucose absorption from intestine, the-reby decreasing postprandial hyperglycemia; metigli-nides like repaglimide and nateglamide, which are insu-lin secretogogues.

Herbal Remedies & Importance of Ayurveda Herbs

Many of the herbs and spices used by humans to season food yield useful medicinal compounds (Lai & Roy, 2004). . The use of herbal medicines in the right way provides effective and safe treatment for many ailments. The effectiveness of the herbal medicines is mostly subjective to the patient. The potency of the herbal medicines varies based on the genetic variation of the herbs, growing conditions of the herbs, timing and method of harvesting of the herbs, exposure of the herbs to air, light and moisture, and type of preservation of the herbs. Herbal medicines can be used for healing purposes and to promote wellness.

Herbal medicines are often used as therapeutic remedies in combination with allopathic drugs (Ramesh, 2003). Most of the doctors did not report any complication, but nausea, vomiting, gastric problems were the common adverse effects reported with PHFs (Poly-herbal formulations). Usually ayurvedic drugs are being used due to their minimum toxicity (Babara, 1993).

As per ancient literature, more than 800 plants are reported to have anti-diabetic properties (Eddouks M, Maghrani M. , 2004 ) . Ethnopharmacological surveys indicate that more than 1200 plants are used in traditional medicine for their alleged hypoglycemic activity (Kesari A N,et all, 2007) . Medicinal plants, since times immemorial, have been used in virtually all cultures as a source of medicine. A study of ancient literature indicates that diabetes was fairly well known and well conceived as an entity in ancient India. The knowledge of the system of diabetes mellitus, as the history reveals, existed with the Indians since prehistoric age. Its earliest reference (1000 BC in the Ayurvedic literature) is found in mythological form where it is said to have originated by eating Havisha, (Latha M, Pari L, 2003) a special food, which used to be offered at the times of yagna organized by Dakshaprajapati. The basis prescription of Ayurvedic drugs was mainly found to be past experience of the patients.

In present paper is an attempt made to explore the Ayurveda plants which show inhibitory effect of glucose utilization and are in use as anti-diabetic agents. Hence, the present study was performed with the aim of producing an inventory of the plants used to treat diabetes, simultaneously also included those plants which are scientifically justified as anti- diabetic agents.

Ayurveda medicinal plants with anti-diabetic and other beneficial properties

CONCLUSION

All the Ayurveda Herbs discussed in this review have exhibited significant clinical & pharmacological activity. The potency of herbal drugs is significant & they have negligible side effects than the synthetic anti-diabetic drugs. There is increasing demand by patients to use the natural products with anti-diabetic activity.

In recent times there has been renewed interest in the plant remedies. Plants hold definite promises in the management of Diabetes mellitus. Isolation & identification of active constituents from these plants, preparation of standardized dose & dosage regimen can play a significant role in improving the hypoglycemic action. Thus, it can be concluded that the herbs for diabetes have been followed all over the World successfully. Herbs are used to manage Type 1 and Type II diabetes and their complications. The above-mentioned plants have been considered for their possible hypoglycaemic actions and the researchers have carried out some preliminary investigations.

Scientific validation of several Ayurveda plant species has proved the efficacy of the botanicals in reducing the sugar level. However, there are numerous other plants still await scientific inquiry, which have mentioned in the Ayurveda A large number of plants, screened for their anti-diabetic effect, have yielded certain interesting leads as mentioned above, but till to date no plant-based drug has reached such an advanced stage of investigation or development as to substitute or reduce the need for the currently-available oral synthetic drugs.

However, the interest in herbal drug research continues with an expectation that some day or the other, the mankind would be able to bring a safer and more effective compound with all the desired parameters of a drug, that could replace the synthetic medicines for the treatment of Diabetes.

REFERENCES