Medicinal Plants Classification Biosynthesis and ... - Index of

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Vandana Gulati, Ian H. Harding and Enzo A. Palombo
prevention and/or treatment of diabetes. Intriguing questions that await further
elucidation include how plants, plant-derived molecules and diet can be used in the future
to complement current treatment strategies for diabetes.
Introduction
Diabetes mellitus is a metabolic syndrome which results from low levels of insulin when
β cells of the pancreas are not able to secrete sufficient insulin. The symptoms of diabetes are
hyperglycemia (high blood glucose), polyuria (increase in urine production), polydipsia
(increased thirst), blurred vision, lethargy and weight loss. The increasing worldwide
incidence of diabetes mellitus in adults constitutes a global public health burden. It is
predicted that by 2030, India, China and United States will have largest number of people
with diabetes (1, 2). The World Health Organization (WHO) estimates that more than 180
million people worldwide currently have diabetes and this figure is likely to more than
double by 2030. In 2005, an estimated 1.1 million people died from diabetes and almost 80%
of diabetes deaths occurred in low and middle-income countries. Almost half of diabetes
deaths occur in people under the age of 70 years; 55% of diabetes deaths are in women and
the WHO projects that diabetes death will increase by more than 50% in the next 10 years
without urgent action. Most notably, diabetes deaths are projected to increase by over 80% in
upper-middle income countries between 2006 and 2015 (3).
Over time, diabetes can damage the heart, blood vessels, eyes, kidneys, and nerves. The
major complications related to diabetes are diabetic retinopathy, a cause of blindness which
results from long-term accumulated damage to the small blood vessels in the retina, and
diabetic neuropathy, the destruction of nerves as a result of diabetes with common symptoms
of tingling, pain, numbness, or weakness in the feet and hands. Combined with reduced blood
flow, neuropathy in the feet increases the chance of foot ulcers and eventual limb amputation.
Diabetes is among the leading causes of kidney failure and increases the risk of heart disease
and stroke. Ten to twenty percent of people with diabetes die of kidney failure and fifty
percent of people with diabetes die of cardiovascular disease (primarily heart disease and
stroke). The overall risk of dying among people with diabetes is at least double the risk of
their peers without diabetes (3).
[153] Diabetes is categorized into: Type I – Insulin Dependent Diabetes Mellitus (IDDM) –
which is an autoimmune destruction of pancreatic β cells; Type II – Non-Insulin
Dependent Diabetes Mellitus (NIDDM) – which is characterized by insulin resistance
in target tissues; and gestational diabetes which occurs during pregnancy.
In Type I diabetes, there is loss of insulin secreting β cells of the Islets of Langerhans in
the pancreas which causes deficiency of insulin. The main cause of β-cell loss is autoimmune
attack of T-cells. The principal treatment is replacement of insulin.
Type II diabetes is caused by reduced insulin sensitivity due to increased glucose levels
in the blood. Hyperglycemia can be rectified by medications that improve insulin sensitivity
or decrease glucose production by the liver. This condition can be treated by increasing
physical activity, decreasing carbohydrate intake, selection of proper diet, modification of
life-style and losing weight.