Hypoglycemic Activity of Curculigo orchioides Gaertn in Normal and Streptozotocin Induced Diabetic Rats

 

AK Jain1, Naveen Sharma2*, Amit Upadhyay2 and Ashish Dixit2

1G.R.Medical College, Gwalior, M.P.

2Shri RNS Inst. of Pharmaceutical Science and Technology, Sithouli, Gwalior.M.P.-474015

*Corresponding Author E-mail:  naveesharma123@yahoo.co.in

 

ABSTRACT:

The purpose of this study was to study effects of Curculigo orchioides Gaertn rhizome on blood glucose level. The antihyperglycemic efficacy of ethanolic extract of the rhizome was evaluated in normal and streptozotocin-induced diabetic rats (STZ diabetic rats). The extract exhibited significant hypoglycemic activity when compared with the control group and to that of the effect produced by a standard antidiabetic agent Glibenclamide. The result also indicated dose dependent effect. The hypoglycemic effect produced by the extract may be due to the uptake of glucose at the tissue level or inhibition of intestinal absorption of glucose. We conclude that ethanolic extract of Curculigo orchioides Gaertn is a potential hypoglycemic agent and lends scientific support for its use in folk medicine.

 

KEYWORDS: Curculigo orchioides,  Streptozotocin, Glibenclamide, Hypoglycemic

 


 

INTRODUCTION:

Diabetes mellitus is a group of metabolic diseased characterized by hyperglycemia, triglyceridaemia and hypercholesterolemia resulting from defect in insulin secretion action on both6. Diabetes mellitus (DM) is one of the chronic, incurable disease that affect individuals, families and society at large. Its short and long-term complications include micro vascular complications   and macro vascular complications. These in turn have a negative impact on health related quality of life1. The incidence, prevalence and hospital admissions, due to diabetes mellitus are increasing day by day world wide. As per the epidemiological surveys, 150 million people have diabetes and 300 million people are likely to be affected by 2025 across the world. Among them, one out of every five diabetes patients may be an Indian. Diabetes mellitus may soon become the major disease of the world as a stated by international diabetes federation (IDF)1. Herbal medicine has been long used for the treatment of diabetic patients and continues to be currently accepted as an alternative therapy. More than 1200 plants have been described in the scientific and popular literature as exhibiting antidiabetic properties5. Many herbal medicines have been recommended for the treatment of diabetes. Plant drugs are frequently considered to be less toxic and free from side effects than synthetic ones6.

 

MATERIAL AND METHODS:

Plant Material:

Rhizomes of Curculigo orchioides Gaertn were obtained from Jiwaji University, city center, Gwalior M.P. (India). The rhizomes were authenticated by Dr. O.N Kaul, Jiwaji University, Gwalior.

 

Preparation of Extract:

The rhizome of the Curculigo orchioides Gaertn were dried and powdered in a mixer.  A fine course powder was obtained which was sieved through # 40, to obtained uniformly. Continuous Soxhlet extraction method was used, the powder of rhizome was packed in a thimble made of what man filter paper and then inserted in to the extractor. Each batch was extracted for about 35 cycles. Extract obtained was concentrated by evaporation. The residue was air dried to remove the solvent. The extract obtained was sticky, semisolid dark brownish colored mass.

 

Acute Toxicity Studies:

Albino mice of either sex weighing 20-30g. They were individually housed in polypropylene cages, in well ventilated rooms, under hygienic conditions. Animals were given, water ad libitum and were fed with rat pellet feed. Acute toxicity studies were conducted to determine for safe dose by an up and down staircase method4. Drug were administrated intraperitoneally to over night fasted animals. After administration, the animals were observed continuously for one hour, for the next four hours and then after 24 hours.

 

 

 


Table No. 1-Hypoglycemic effect of single dose administration of extract in normal rats. 

Groups

Dose

Fasting blood sugar in mg/dl (Mean ±S.E.)

Control

2ml of 0.2% Gum acacia

0 hr.

1 hr.

2 hr.

4 hr.

6 hr.

110±3.5

108±2.7

112±3.7

111±3.8

109±4.5

Ethanolic extract of Curculigo orchioides

200mg/kg

110.3±3.7

109±3.2

107.2±5.2

101.42±2.7

100.35±3.7

 
Table No. 2-Hypoglycemic effect of chronic administration of extract in normal rats.

Groups

Dose

Fasting blood sugar in mg/dl (Mean ±S.E.)

Control

2ml of 0.2% Gum acacia

0 day

2 day

4 day

7 day

15 day

107.52±3.8

109.3±2.5

111.34±5.6

1108.5±4.6

110.4± 7.2

Ethanolic extract of Curculigo orchioides

200mg/kg

99.5±2.0

94.3±1.8

86.8±4.8

80.7±3.7

72.4±6.5

 


Antidiabetic Studies5 [Experimental Protocol]:

Normal Rats:

·         Group I – received vehicle, 0.2% gum Acacia solution

·         Group II – received ethanolic extract of Curculigo orchioides Gaertn

 

Diabetic Rats:

·         Group I - received vehicle, 0.2% gum Acacia

·         Group II – received ethanolic extract of Crculigo orchioides Gaertn

·         Group III – received standard drug – glibenclamide

 

Selection and Preparation of doses:

The dose select for the extract were bout 1/10th of the safe dose found in acute toxicity studies. They were administered once daily by oral route. The dose 200mg/kg was selected for this study; ethanolic extract and glibenclamide were suspended in 0.2% acacia solution.   The dose of standard drug selected was 0.25 mg/kg. This was calculated the minimum human dose to the rats and the past experience with the drug.

 

Selection of Animals:

Albino rats of Wister strain of either sex, weighing, 150-250gm, bred in our own animals house were selected. They were individually housed in polypropylene case, in well ventilated rooms, under hygienic condition. Animals were given, water ad libitum and were fed with rat pellet feed.

 

Studies in Normal Rats:

The hypoglycemic effect of Curculigo orchioides Gaertn extract was studied in normal rats, following 15 days treatment. In this experiment, two groups of rats were used in each group 6 rats taken. Group first received 0.2% gum acacia. Solution once a day orally up to 15 days and serve as a control group second received extract of Curculigo orchioides Gaertn once a day for 15 days.

 

Hypoglycemic Studies:

Blood sample were withdrawn from overnight fasting animal on 0hr, 1hr, 2hr, 6hr, after single oral administration and after 2 days, 4 days, 1 week and 2 weeks, after vehicle or extract administration. Blood was withdrawn from the retro orbital plexus using heparinized haematocrits. The fasting blood sugar levels were estimated using glucose estimation kit.

 

Study in Diabetic Rats:

Induction of Diabetes

The selected animal of 90 days was weighing between 175-250g of either sex preferably intravenous injection of STZ in to the tail vein at dose of 65 mg/kg. STZ was previously dissolved in 0.1 m cold sodium citrate buffer, PH -4.5, eighteen hours after the STZ injection. Rat with fasting blood glucose levels greater than 16.5 m mol L-1 were considered diabetic and then include in this study. The experiment was performed in diabetic rats 20 hr after STZ injection. 


Hypoglycemic Studies

The diabetic rat after conformation of stable hyperglycemia, were divided in three groups of six rats each.

Group 1st -Group 1st received 2 ml of 0.2% gum acacia as a control vehicle, for 15 days once in a day.

Group 2nd- Group 2nd received Curculigo orchioides Gaertn extract (250 mg/kg) for 15 days once in a day.

Group 3rd-   Group 3rd received standard drug glibenclamide (0.25 mg/kg body weight) for 15 days once in a day.

 

Statistical Analysis:

Results of biochemical estimation were reported as mean ± S.E. The total variation present in a data was analyzed by one way analysis of variance (ANOVA). Differences among the means were analyzed by Dennett’s t-test. For this, a window based SPSS computer package was used. Far comparing the blood sugar values, before and after drug administration (acute effect), paired student “t” was employed.

 

RESULTS:

Hypoglycemic Studies in normal rats: -

In the single dose administration of ethanolic extract on 0hr, 1hr, 4hr, 6hr, extract produced a significant decrease in blood glucose levels after 2 hours when compared with the starting value (P<0.05) with maximal reduction was reached 4 hour after oral administration (P<0.01). Once daily repeated oral administration of Curculigo orchioides Gaertn for 2 week produced in normal rats, a potent decrease in blood glucose level after 4, 7, 15 days of the treatment (P<0.001).

 

Hypoglycemic Studies in Diabetic Rats:

In control diabetic rat, blood glucose level was significantly increased from the second day. This increment could be due to the early appearance of insulin resistance in adult STZ diabetic rat or glucotoxicity associated with chronic hyperglycemia. In STZ diabetic rats, after single oral administration of Curculigo orchioides Gaertn, blood glucose level drops significantly (P < 0.01) reduction was observed four hour after treatment.


Table No. 3- Hypoglycemic effect of single dose administration of extract in diabetic rats.

Groups

Dose

Fasting blood sugar in mg/dl (Mean ±S.E.)

Normal diabetic Control

2ml of 0.2% Gum acacia

0 hr.

1hr.

2hr.

4hr.

6hr.

350.6±15

345.5±17

340.7±18

342.8±11

335± 14

Glibenclamide

0.25 mg/kg

330.8±16

310.9±17

290.8±16

272.9±11

258.8±17

Ethanolic extract of Curculigo orchioides

200mg/kg

335.9±14

324.8±15

309.9±11

283.7±13

279.9±18


Table No.4- Hypoglycemic effect of chronic administration of extract in diabetic rats.

Groups

Dose

Fasting blood sugar in mg/dl (Mean ±S.E.)

Normal diabetic Control

2ml of 0.2% Gum acacia

0 day

2 day

4 day

7 day

15 day

310.6±10.4

308.8±15

300±11

296±14

290±17

Glibenclamide

0.25 mg/kg

250±12

230±18

190±17

165±9

122±14

Ethanolic extract of Curculigo orchioides

200mg/kg

260±13

235±15

195±11

171±12

132±14

 

 


However, treatment with extract of Curculigo orchioides Gaertn for 15 days produced a reduction in blood glucose level from the 4th day (P<0.001). In 2nd week of treatment the blood glucose levels were very low, indicating the just above the normal state.

 

DISCUSSION:

The aim of this study was to investigate the Hypoglycemic effect of ethanolic extract of Curculigo orchioides Gaertn in normal and Streptozotocin induced diabetic rats. In the present study the ethanolic extract of Curculigo orchioides Gaertn produced hypoglycemic effect in both single and chronic dose administration, studies conducted in both normal and Streptozotocin induced diabetic rats. Our study indicate that the ethanolic extract of Curculigo orchioides Gaertn exhibit a potent and cumulative hypoglycemic effect in normal rats after both single and repeated administration for 15 days. In streptozotocin diabetic rat, single oral administration of Curculigo orchioides Gaertn blood glucose levels drops significantly (P<0.05) and maximal reduction was observed 4 hour after treatment (P<0.01). in diabetic rat Curculigo orchioides Gaertn exhibit a potent and cumulative hypoglycemic effect (P<0.001) both single and repeated oral administration for 15 days.

 

The extract of Curculigo orchioides Gaertn had no effect on basal plasma insulin concentration in either normal or diabetic rat, indicating that this plant extract exerts hypoglycemic effect independently of insulin secretion. This blood glucose lowering activity may be due to stimulation of peripheral glucose consumption or inhibition of intestinal or renal glucose absorption or inhibition of endogenous glucose production. We conclude that an ethanolic extract of Curculigo orchioides Gaertn was effective in decreasing blood glucose level in normal and Streptozotocin induced diabetic rats via and extra pancreatic action, since the basal insulin release from β-cells of   Islets of Langerhans did not show any significant change after Curculigo orchioides Gaertn finally the precise mechanism and site of this activity of Curculigo orchioides Gaertn in world are still to be determined and further toxicological studies are needed.

 

REFERENCES:

1.        Chatopadhyay, S., et al 1997 “Animal models of in experimental diabetes mellitus”. Ind. J. Exp. Biol., 35: 1141-1145.

2.        Dixit V.K., Chauhan N. S., Antihyperglycemic activity of the ehtanolic extract of curculigo orchioides, PHCOG MAG. Vol 3,2008.

3.        Eddouks M., Lemhadri A.,et al, Hypoglycemic effect of Calamintha officinalis Moench. In normal and streptozotocin induced diabetic rats, Journal of Pharmacy and Pharmacology 2004,56;795-799.

4.        Expert Committee Report of the Expert Committee on Diagnosis and classification of Diabetes Mellitus. Diabetes care, 1997; 20;1183-1195

5.        Ghosh, M. N. Fundamentals of experimental pharmacology, scientific book agency, Calcutta, 1984; 153.

6.        Mahendra Kumar B.J., impact of patient education in a south Indian community pharmacy on health related quality of life in patient with Diabetes Mellitus. 2005; 34.



 

 

 

Received on 07.08.2009          Modified on 15.10.2009

Accepted on 20.12.2009         © RJPT All right reserved

Research J. Pharm. and Tech. 3(1): Jan. - Mar. 2010; Page 133-135