Anti-diabetic activity of ethanolic extract of Holostemma ada Kodien Schults in alloxan induced diabetic rats
Y Janapati, R Ahemad, K Jayaveera, R Reddy
Keywords
alloxan, antidiabetic, eehk, holostemma ada kodien
Citation
Y Janapati, R Ahemad, K Jayaveera, R Reddy. Anti-diabetic activity of ethanolic extract of Holostemma ada Kodien Schults in alloxan induced diabetic rats. The Internet Journal of Endocrinology. 2008 Volume 5 Number 2.
Abstract
Introduction
Diabetes mellitus (DM) is considered to be one of the most serious endocrine syndrome. In many countries it is traditional to use plants to control diabetes 1234 . The anti hyperglycemic effect of several plant extracts which were used as antidiabetic remedies has been confirmed [[[5,6,7,8.]]] . The synthetic hypoglycemic agents used in clinical practices have serious side effects like hematological effects, coma, disturbs the functions of liver and kidney. In addition they are not suitable for use during pregnancy 9 . Compared with synthetic drugs, drugs derived from plants are frequently considered to be less toxic with fewer side effects 10 . Therefore, the search for more effective and safer antidiabetic agent has become an area of active research.
Materials And Methods
Plant Material
Fresh leaves were collected from S.V.U campus, Tirumala gardens of Chittor district of Andhra Pradesh of India and authentified by Asst.Prof.Dr.K.Madhava Chetty of the Department of Botany, S.V.University, and Tirupathi. A.P. A voucher specimen [No.HAK1/PRRMCP 06-11] was deposited at Department of Pharmacognosy for further reference.
Extraction
The leaves, shade dried, powdered in a grinder mixer to obtain a coarse powder and then passed through 40 mesh sieve. The powdered leaves (430gms) were defatted with hexane and later extracted (soxhlet) using alcohol. The extract evaporated to dryness, gave a residue 15.5%w/w. Phytochemical screening 16 were performed.
Animals
Albino wistar rats of either sex weighing (200-250gms) were employed for study. They were housed in standard environmental conditions and fed with standard rodent diet with water
Toxicity study
An acute toxicity study was performed to determine the LD50 using different doses of the extract according to the method described by Ghosh et.al 17 .
Effects of EEHK on blood glucose levels in normoglycemic rats
Animals were divided into three groups of six rats in each group. Group-1: Animals received 1% SCMC 2 ml/kg body wt. per orally. Group-2: Animals received EEHK 200 mg/kg body wt. per orally.Group-3: Animals received EEHK 400 mg/kg body wt. per orally.
In this study the entire groups of animals were fasted over night and administered with respective drugs as per the above mentioned dosage schedule. Blood glucose levels were determined at 0 (before drug challenge) 60, 120 min, after drug administration
Effect of EEHK on blood glucose level on glucose fed hyperglycemic rats (oral glucose tolerance test)
The animals were divided into four groups of six rats in each group. Group-1: Animals received glucose at a dose 2 gm/kg body wt. per orally.
Effect of EEHK on blood glucose level in alloxan induced diabetic rats
Different groups of rats were used to study the effects of EEHK. The rats were divided into five groups each consisting of six rats.
In this study all the surviving diabetic animals and normal animals were fasted over night. Blood samples were collected from the fasted animals prior to the treatment with above schedule and after administration at each day up to 7days. For glucose determination, blood was obtained by snipping tail with sharp razor 18 using Haemo-Glukotest (20-800R) glucose strips supplied by M/s Boehringer Mannheim India Ltd. This method, which permits the measurement of blood glucose levels with minimum injury to rat, was previously validated by comparison with glucose oxidase method 1920 .
Statistical Analysis
All values were expressed as mean ± SEM .The data were statistically analysed by ANOVA followed by Dunne’s -‘t’ test 21 .
Results
Phytochemical and toxicity studies
Phytochemical screening gave positive results for alkaloids, flavonoids, flavanones, tannins, terpenoids, amino acids and carbohydrates. In toxicology study it was observed that extract is non toxic upto 5 g/kg body weight.
Effects of EEHK on blood glucose levels in normoglycemic rats
At dose 200 mg/kg and 400 mg/kg of EEHK in fasting rats, blood sugars level were assessed in normal rats at various time intervals. The results were shown in Table-1.The mean blood glucose level maintained at 83.00 mg/dl at dose of 200 mg/kg body weight of EEHK and decreased from 88.60 mg/dl to 84.00 mg/dl at dose of 400 mg/kg body weight in rats treated with EEHK.
Figure 1
Effect of EEHK on blood glucose level on glucose fed hyperglycemic rats (oral glucose tolerance test)
At dose 200 mg/kg and 400 mg/kg of EEHK blood sugars level were assessed in glucose fed rats at various time intervals. The results were shown in Table-2.The mean blood glucose level decrease from 88.33 mg/dl to 86.17 mg/dl at dose of 200 mg/kg body weight of EEHK and 90.67 mg/dl to 85.44 mg/dl at dose of 400 mg/kg body weight in rats treated with EEHK, which is comparable to standard drug administration which shows reduction of mean blood glucose level from 86.16 mg/dl to 80.67 mg/dl.
Figure 2
Effect of EEHK on blood glucose level in alloxan induced diabetic rats
The antihyperglycemic effect of the extracts on the blood sugar level on diabetic rats is shown in Table-3. The blood glucose level of diabetic animals significantly reduced from 207.30 mg/dl to 105.10 mg/dl at 200 mg/kg body wt. of EEHK and 212.83 mg/dl to 89.16 mg/dl at 400mg/kg body wt. of EEHK. These results were comparable with 0.5mg/kg of glibenclamide which shows significant reduction from 213.00 mg/dl to 86.16 mg/dl on 7 th day.
Figure 3
Discussion
In the recent times many traditionally used medicinally
Preliminary phytochemical analysis of the ethanolic extract of the
The ethanolic extract at a dose of 200 mg/kg body wt. per orally did not significantly suppress blood glucose levels in over night fasted normoglycemic animals. The same effect was observed at a higher dose of 400 mg/kg body wt. per orally of the EEHK in over night fasted normoglycemic animals after 1 st and 2 nd hour of oral administration, when compared with control group of animals.
The ethanol extract showed significant improvement in glucose tolerance in glucose fed hyperglycemic normal rats. Such an effect may be accounted for, in part, by a decrease in the rate of intestinal glucose absorption, achieved by an extra pancreatic action including the stimulation of peripheral glucose utilization or enhancing glycolytic and glycogenic process with concomitant decrease in glycogenolysis and glyconeogenesis 22 . However the effect was less significant when compared to standard drug glibenclamide.
Alloxan is the most commonly employed agent for the induction of experimental diabetic animal models of human insulin-dependent diabetes mellitus. There is increasing evidence that alloxan causes diabetes by rapid depletion of β cells, by DNA alkylation and accumulation of cytotoxic free radicals that is suggested to result from initial islet inflammation, followed by infiltration of activated macrophages and lymphocyte in the inflammatory focus. It leads to a reduction in insulin release, thereby a drastic reduction in plasma insulin concentration leading to stable hyperglycemic state 23 . In this study significant hyperglycemia was achieved within 48 hours after Alloxan (150 mg/kg body wt. i.p.) injection. Alloxan induced diabetic rats with more than 200 mg/dl of blood glucose were considered to be diabetic and used for the study.
The studies on antidiabetic activity in alloxanised rats showed significant reduction of blood glucose level from the 4 th day of the study. The comparable effect of the extract with glibenclamide may suggest similar mode of action, since alloxan permanently destroys the pancreatic cells and the extract lowered blood sugar level in alloxanised rats, indicating that the extract possesses extra pancreatic effects 24 . From the phytochemical analysis it was found that the major chemical constituents of the extract were flavonoids and tannins. Over 150 plant extracts some of the active principle including flavonoids are known to be used for the treatment of diabetes 25262728 . On the basis of the above evidences it is possible that the presence of flavonoids and tannins are responsible for the observed anti diabetic activity 2930 .
Correspondence to
Yasodha Krishna Janapati, M.Pharm,
Department of Pharmaceutical Chemistry,
P.Rami Reddy Memorial College of Pharmacy,
Kadapa, India.
Email:Krishna.yasodha@gmail.com,
Ph No: +919703282867.