الفهرس 
Epidemiology of diabetes mellitusOnly 14 pages are availabe for public view
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Abstract
Diabetes mellitus (DM) is one of the most critical health
problems in the 21st century in both developed and developing
countries. The international diabetes federation reported that the
incidence of diabetes has increased from 4.7% at 1980 to 8.5%
at 2016 in the adult population. Egypt is ranked the eighth in the
world in terms of diabetes. There are three main types of DM;
type 1 (T1DM) which accounts for 5-10 % of diabetic patients
and in which patients must be supplied with external insulin.
The second type is called T2DM which accounts for about 90%
of all diabetics and is characterized by insulin resistance.
Gestational diabetes usually occurs during pregnancy due to the
antagonistic effect of placental hormones to insulin and usually
disappears after labor.
Insulin plays a critical rule in glucose homeostasis, for
normal insulin signal, insulin should bind to its receptor and
activates two important proteins called insulin receptor substrate
1 and 2 (IRS1 and IRS2). T2DM is characterized by insulin
resistance as insulin failed to bind its receptor to induce
activation of tyrosine kinase activity of the intracellular subunit
of its receptor and therefore the sensitivity of target tissues to
insulin decreases. Several hepatokines are involved in glucose
and lipid metabolism. Impairment of such essential hepatic
cytokines may lead to impaired insulin sensitivity and increased
hepatic glucose production and lipogenesis Morbidity and mortality due to diabetes cause a heavy
economic stress on health care system so that there is a strong
need to create new strategies and drugs for controlling DM.
Medicinal plants considered a natural and safe source for active
compounds used for treatment of many diseases since many
decades. Pterocarpus santalinus is one of the medicinal plants
with an anti-diabetic effect.
In the current study, T2DM was established using a single
dose of 65mg/kg of streptozotocin (STZ). Fourty two male rats
were divided into seven groups of six rats each as follows:
-The first group was the control and sacrificed after 4 weeks.
-The second group received the aqueous plant extract
(250mg/kg) orally and daily for three weeks.
-The third group (STZ1) was intraperitoneally (i.p) injected
with a single dose of 65mg/kg of streptozotocin (STZ) and
sacrificed after four weeks.
-The fourth group was injected with a single dose of STZ then
after one week it was treated orally with the aqueous plant
extract daily for three weeks, then sacrificed.
-The fifth group was injected with a single dose of STZ then
after one week it was treated orally with 3 mg/kg of reference
drug (glustin) daily for three weeks, then sacrificed.
-The sixth group (STZ2) received standard food pellets for
three weeks then injected with a single dose of STZ then
sacrificed after one week.-The seventh group was administered with the plant extract
daily for three weeks then injected with a single dose of STZ
then sacrificed after one week.
The effects of both the plant extract and STZ were studied by
measuring the body weight change, FBS, insulin, HbA1c,
HOMA-IR, liver function, kidney function and lipid profile. The
mRNA expression of fetuin-A, SIRT-1, c-JNK and IRS-1 was
measured by qRT-PCR. Histopathological examination was
performed for sections of pancreas. In addition, the HPLC
analysis of plant extract was performed.
Streptozotocin was able to induce T2DM. The levels of
glucose, HOMA-IR and HbA1c were elevated while insulin
level was significantly decreased. Liver enzymes were not
affected by STZ. Urea level was elevated by STZ while
creatinine was unchanged. Lipid profile was not affected by
STZ. STZ caused a down-regulation of mRNA expression of
fetuin-A while both JNK and SIRT-1 were up-regulated. STZ
did not cause any significant change in IRS-1 mRNA
expression.
The plant extract was able to ameliorate the deteriorations
caused by STZ. When diabetic rats were treated with the
extract, the levels of glucose, HOMA-IR and HbA1c were
decreased and insulin was elevated. The plant extract caused a
significant amelioration of both creatinine and urea levels. The
plant extract caused a down-regulation of mRNA expression of JNK and SIRT-1 while mRNA expression of IRS-1 was upregulated.
Glustin did not ameliorate the deteriorations caused by STZ
and failed to improve insulin resistance. Glustin caused a
significant decrease in AST activity and LDL-chol level.
Treating diabetic rats with glustin caused up-regulation of
fetuin-A mRNA expression while both SIRT-1 and JNK were
down-regulated.
The plant extract did not protect against induction and
progression of DM.