Medicinal Plants Classification Biosynthesis and ... - Index of

Management of Diabetes with Diet and Plant-Derived Drugs
Gestational diabetes, although temporary, increases the risk of developing Type II
diabetes later in life. Although insulin injections are sometimes necessary, this type of
diabetes is also commonly treated by life style changes such as moderate physical activity
and diet.
The principal clinical features of diabetes mellitus were described by Hindu scholars as
long ago as about 1500 BC as a condition featuring polydipsia, polyuria and the production
of urine which was sweet enough to attract flies and ants (4). The current focus of drug
discovery research in diabetes includes exploration of alternative medicines, discovery of
new synthetic antidiabetic agents as well as isolation of active compounds from plants which
have been the source of traditional herbal medicines and have been documented and
described for their antidiabetic properties in ancient texts like Ayurveda. The WHO has
recommended that alternative medicines should be investigated and explored for discovery of
new drugs for the treatment of diabetes mellitus (5).
Current Therapies for Diabetes
Currently available therapies for diabetes include insulin and various oral antidiabetic
agents such as sulfonylureas, biguanides, α-glucosidase inhibitors, α-amylase inhibitors and
glinides, which are used as monotherapy or in combination to achieve better glycemic
regulation. The medications available in the market, and their side effects, are as follows and
are summarized in Figure 1:
Metformin, is the only biguanide available to most of the world and its major effect
is to decrease hepatic glucose output and lower fasting glycemia. It is generally well
tolerated, with the most common adverse effects being gastrointestinal.
Sulfonylureas lower glycemia by increasing insulin secretion. The major adverse
effect is hypoglycemia, while weight gain is also a common concern.
Glinides, like the sulfonylureas, also stimulate insulin secretion but bind to a
different site within the sulfonylurea receptor and have a shorter half-life than the
sulfonylureas and therefore must be administered more frequently. The glinides have
a similar risk for weight gain as the sulfonylureas, but hypoglycemia may be less
frequent (nateglinide) than with some sulfonylureas.
Enzyme inhibitors lower the rate of digestion of polysaccharides in the proximal
small intestine, primarily lowering postprandial glucose levels without causing
hypoglycemia. Since carbohydrates are absorbed more distally, malabsorption and
weight loss are ameliorated, however, increased delivery of carbohydrate to the
colon commonly results in gas production and gastrointestinal symptoms.
Thiazolidinediones (TZD) or glitazones are peroxisome proliferator–activated
receptor γ modulators which increase the sensitivity of muscle, fat, and liver to
endogenous and exogenous insulin (―insulin sensitizers‖). The most common
adverse effects with TZDs are weight gain and fluid retention.
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