A Review of Recent Investigations on Medicinal Herbs Possessing Anti-Diabetic Properties

Abstract

Globally, the pervasiveness of chronic, non-communicable disease diabetes mellitus is growing by leaps and bounds. It is one of the major causes of premature morbidity and mortality worldwide. Almost 3.2 million people die of diabetes across the world every year. The worldwide prevalence of diabetes is 6.4% (corresponding to 285 million people); this varies from 10.2% in the Western Pacific to 3.8% in the African region and expected to grow up to 7.4% (439 million) of the adult population by 2030. In the last 20 years there has been a threefold increase in the prevalence of diabetes. It is estimated that there are 30 to 33 million diabetics in India now, and every fourth diabetic in the world today is an Indian. Indians are genetically more susceptible to diabetes and the WHO predicts the number of diabetics in India would go up to 80 million by 2030. WHO has also issued a warning that India is going to be the diabetes capital of the world with Chennai emerging as the diabetic capital of India. Many plants possessing hypoglycemic principles/ properties are known to exist in nature. Also a large number of polyherbal formulations (PHF's) derived from these plants are presently being prescribed as medicinal/dietary supplements for diabetes mellitus. Even the WHO (World Health Organization) approves the use of plant drugs for different diseases, including diabetes mellitus. However, these formulations lack proper standardization of the active constituents. There is an urgent need to address to the issues of scientific authenticity about their efficacy, safety and their interaction with modern allopathic drugs. The paper reviews composition, active principles and pharmacological effects of some important plants which are widely used in commercially available herbal and polyherbal formulations and provides a detailed list of plants reported to possess potential anti-diabetic activity.

Methanolic Root Extract ofRauwolfia serpentinaBenth Improves the Glycemic, Antiatherogenic, and Cardioprotective Indices in Alloxan-Induced Diabetic Mice

“…Similarly, flavonoids, alkaloids, and saponins were found as 97, 7, and 20 mg/gm in root powder of same herb. A vast literature provides scientific evidence that plants rich in flavonoids possess potent antidiabetic, hypolipidemic, hypotensive, anti-inflammatory, and antioxidative activities [5, 38]. …”

“…On the contrary, plant-based medicines are water soluble with no side effect. It has been reported that over 80%, world population is dependent on herbal medicine for their therapeutic benefits [4], and more than 800 plant species have been mentioned in the literature with significant hypoglycemic activity [5]. However, searching for new antidiabetic drug from natural sources including herbs is still an attractive research aspect as these are cost effective substances with no side effect.…”

Overview of food products and dietary constituents with antidiabetic properties and their putative mechanisms of action: A natural approach to complement pharmacotherapy in the management of diabetes

“…The incorporation of soluble fibers from different sources such as oat , barley , guar gum , and high‐viscosity hydroxypropylmethylcellulose , into a meal has been shown in many clinical studies to reduce postprandial insulin and glucose responses. Fenugreek, a leguminous herb commonly used in Indian and Middle Eastern cuisine, has been used for decades in the treatment of diabetes . Over 30 studies in animal models and humans have reported on the antidiabetic properties of this plant's seeds .…”

“…Medicinal plants, herbs, and their derivatives have been used for centuries in the traditional treatment of diabetes, and are being studied intensively for their mechanism of action and active principles . The consumption of various foods has also been shown in animal and human studies to have positive impacts on blood glucose regulation (e.g.…”

In Vivo Subacute Toxicity and Antidiabetic Effect of Aqueous Extract of Nigella sativa

“…Elsewhere, various plants have been found to possess significant antidiabetic property after their preclinical and clinical evaluation [5]. …”