Year : 2009  |  Volume : 1  |  Issue : 4  |  Page : 326-329 Table of Contents     

Hypoglycemic effect of Leucas lavandulaefolia willd in alloxan-induced diabetic rats

1 Department of Pharmacognosy, NGSM Institute of Pharmaceutical Sciences, Paneer, Deralakatte, Mangalore-574 160, India
2 Department of Community Medicine, Father Muller Medical College, Mangalore-575 002, India

Date of Web Publication25-Jan-2010

Correspondence Address:
K S Chandrashekar
Department of Pharmacognosy, NGSM Institute of Pharmaceutical Sciences, Paneer, Deralakatte, Mangalore-574 160
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DOI: 10.4103/0975-1483.59322

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Leucas lavandulaefolia Willd. is mainly used in Indian folk medicine for the treatment of diabetes mellitus. The oral administration of 0.15, 0.20 and 0.25 g/kg of chloroform extract of the Leucas lavandulaefolia flowers (LLFEt) for 30 days resulted in a significant reduction in blood glucose, glycosylated hemoglobin and an increase in total hemoglobin, and the effect was highly significant in the case of 0.25 g/kg. It also prevents decrease in body weight. Oral glucose tolerance test was also performed in experimental diabetic rats in which there was a significant improvement in glucose tolerance in animals treated with LLFEt and the effect was compared with glibenclamide. Thus, the study shows that LLFEt has hypoglycemic action.

Keywords: Diabetes, glucose, hypoglycemic, Leucas lavandulaefolia

How to cite this article:
Chandrashekar K S, Prasanna K S. Hypoglycemic effect of Leucas lavandulaefolia willd in alloxan-induced diabetic rats. J Young Pharmacists 2009;1:326-9

How to cite this URL:
Chandrashekar K S, Prasanna K S. Hypoglycemic effect of Leucas lavandulaefolia willd in alloxan-induced diabetic rats. J Young Pharmacists [serial online] 2009 [cited 2013 Oct 18];1:326-9. Available from: /text.asp?2009/1/4/326/59322

   Introduction Top

Leucas lavandulaefolia Willd. is a herbaceous annual weed found in pastures and waste land throughout India. It is erect, slightly pubescent or tomentose, 0.3 to 0.75 m in height, usually branched; branches are quadrangular, pubescent. Flowers are sub sessile or shortly pedicellate, in axillary and terminal whorls 1.3 to 2 cm diameter 1.3 to 2 cm diameter, toward the end of the branches. It has been used as an antidiabetic agent in traditional system of medicine in India. [1] It has strong flavors and is reputed for its use as sedative, vermifuge, stomachic dermatosis and is also useful in the treatment of migraine. [2] It has also been extensively used by rural people of Mithila region (Bihar) in human and cattle ailments, such as cough, cold skin diseases, headache and snake bite. [3] Isolation of flavonoid glycoside from the flowers of Leucas lavandulaefolia using chloroform extract was reported earlier. [4] Hypoglycemic activity of Leucas lavandulaefolia in streptozotocin-induced diabetic rats has been investigated. [5] Synthetic hypoglycemic agents can produce serious side effects including hematological, coma and disturbances of liver and kidney. In addition, they are not suitable for use during pregnancy. [6] Various parts of Leucas lavandulaefolia Willd. (family: Labiatae) have been used for various medicinal purposes including the treatment of diabetes mellitus. The present investigation was undertaken to study the effect of chloroform extract on Leucas lavandulaefolia flowers (LLFEt) on blood glucose, glycosylated hemoglobin and oral glucose tolerance in alloxan-induced diabetic rats.

   Materials and Methods Top

Plant materials

Leucas lavandulaefolia Willd. flowers were collected freshly from Manipal, Udupi District, Karnataka, India. The plant was identified and authenticated by Dr. Gopalkrishna Bhat, Department of Botany, Poornaprajna College, Udupi. A voucher specimen (NGSM 45) was deposited in Pharmacognosy Department of N.G.S.M. Institute of Pharmaceutical Sciences, Mangalore.

Preparation of chloroform extract of Leucas lavandulaefolia flowers

Almost 250 g of Leucas lavandulaefolia fresh flowers were extracted using 1.5 l of chloroform by the method of continuous hot extraction. [7] Extract was evaporated in a container to a constant weight. Almost 15.5 g of extract was obtained after complete removal of the solvent. The above residual extract was dissolved in sterile water and investigated.

Selection of dose

The albino rats were administered orally a single dose of 2.5, 5 or 10 times of effective dose of chloroform extract of L.lavandulaefolia. The rats were observed for gross behavioral, neurological, autonomic and toxic effect at regular intervals. Food consumption, faeces and urine were also examined at 2 and then at 6-h intervals for 24 h.

Experimental induction of diabetes in rats

Male albino Wister rats of body weight 180-200 g bred in Central Animal House, N.G.S.M. Institute of Pharmaceutical Sciences, Paneer, Mangalore were used in this study. The animals were fed on a pellet diet (Hindustan Liver, India) and water ad libitum. The rats were injected with Alloxan monohydrate dissolved in sterile normal saline in a dose of 150 mg/kg, intraperitoneally. As Alloxan is capable of producing total hypoglycemic as a result of massive pancreatic insulin release, rats were treated with 20% glucose solution (15-20 ml) intraperiatoneally after 6 h. The rats were then kept for the next 24 h on 5% glucose solution bottles in their cages to prevent hypoglycemia. [8] After two weeks, rats with moderate diabetes having glycosuria (indicated by Benedict's test for urine) and hypoglycemia with blood glucose range of 200-260 mg/100 ml were used for the experiment. Blood was collected from the eyes (venous pool).

Determination of blood glucose and hemoglobin

  • Fasting blood glucose was estimated by o-toluidine method. [9]
  • Hemoglobin was estimated by cyanmethaemoglobin method. [10]
Determination of glycosylated hemoglobin

Glycosylated hemoglobin (GHb) was estimated by the method of Sudhakar Nayak and Pattabiraman. [11]

Effect on oral glucose tolerance in rats

After overnight fasting, a 0-min blood sample (0.2 ml) was taken from the rats in different groups viz., normal, diabetic control, diabetic + LLFEt (0.25 g/kg) and diabetic + Glibenclamide (600µg/kg) by the orbital sinus puncture [12] without delay a glucose solution (2 g/ml per kg) was administered by gavage. Four more samples were taken at 30, 60, 90 and 120 min after glucose administration. [13] All blood samples were collected with potassium oxalate and sodium fluoride solution for the estimation of blood glucose.

Experimental design

A total of 36 rats (30 diabetic surviving rats, six normal rats) were used for the experiment. Diabetes was induced in rats two weeks before starting the experiment. The rats were divided into six groups after the induction of Alloxan diabetes. In the experiment, six rats were used in each group:

­­­Group 1 Normal untreated rats;

Group 2 Diabetic rats;

Group 3 Diabetic rats that were given Leucas lavandulaefolia flower extract (LLFEt) (0.15 g/kg) in aqueous solution daily using an intragastric tube for 30 days;

Group 4 Diabetic rats that were given LLFEt (0.20 g/kg) in aqueous solution daily using an intragastric tube for 30 days.

Group 5 Diabetic rats that were given LLFEt (0.25 g/ kg) in aqueous solution daily using an intragastric tube for 30 days; and

Group 6 Diabetic rats that were given given Glibenclamide orally (600 ìg/kg) in aqueous solution daily using an intragastric tube for 30 days.

After 30 days, the rats were sacrificed by decapitation. Blood was collected in a tube containing potassium oxalate and sodium fluoride solution for the estimation of blood glucose. The experiments were repeated in same number of rats.

Statistical analysis

All the group data were statistically evaluated and the significance of various treatments was calculated using Student's t-test. All the results were expressed as mean ± S.D.

   Results Top

No toxic effect was reported up to 5 and 10 times of effective dose of the chloroform extract. [Table 1] demonstrates the blood glucose, total hemoglobin, glycosylated hemoglobin, change in body weight and urine sugar of normal and experimental animals. There was a significant elevation in blood glucose (P < 0.001), glycosylated hemoglobin (P < 0.001) while the level of total hemoglobin (P < 0.001) decreased during diabetes when compared with the corresponding groups. Administration of LLFEt at 0.02 and values near normal LLFEt at a dose of 0.25 g/kg shows highly significant effect, when compared with glibenclamide. [Table 2] gives the blood glucose of control, diabetic control LLFEt and glibenclamide treated animals after oral administration of glucose (2 g/kg per ml). In LLFEt and glybenclamide treated animals more significantly decreased blood glucose concentration after 1 and 2 h. LLFEt treated animals tend to bring the values near normal. LLFEt (0.25 g/kg) were more effective than glybenclamide.

   Discussion and Conclusion Top

The blood glucose data obtained using Alloxan hyperglycemic rats [Table 1] and [Table 2] clearly shows that the chloroform extract of LLFEt can produce significant and consistent hypoglycemic effects. It is generally accepted that the sulfonyl areas, including glybenclamide produce hypoglycemia in normal animals by stimulating the pancreatic β cells to release more insulin. These drugs, however, do not decrease blood glucose in Alloxan diabetic animals. [14] In contrast to the oral antidiabetic agents, the exogenous administration of insulin is well known to produce hypoglycemia in both normal and Alloxan induced subjects. [6] It is, therefore, conceivable that the hypoglycemia principal(s) in the extract of Leucas lavandulaefolia plants exert a direct effect in diabetic rats. In diabetic rats, LLFEt cannot act indirectly by stimulating the release of insulin since Alloxan treatment causes permanent destruction of β cells. The anti-hyperglycemic effect in the alloxan - diabetic rats suggest, that its main mechanism may not be due to potentiation of insulin release from pancreatic cells and thus the drug may be effective in insulin independent diabetes also, as the significant and consistent hypoglycemic effect LLFEt in diabetic rats after 30 days indicates that the plant extract acts by stimulating glucose utilization by peripheral tissues. These results confirm the earlier findings. [15],[16] Glycosylated hemoglobin was found to increase in patients with diabetes mellitus to about 16% [17] and the amount of this increase is directly proportional to the fasting blood glucose level, [18],[19] we have observed a decrease in total hemoglobin during diabetes and this may be due to the increased formation of glycosylated hemoglobin. Our study also gave a clear view that LLFEt prevents a significant elevation in glycosylated hemoglobin level in diabetic rats that were fed daily for 30 days with LLFEt. We have also observed that LLFEt was administered to animals given Alloxan, the weight loss was reversed and the animals returned to near normal. The ability of the LLFEt to protect body weight loss seems to be due to its ability to reduce hyperglycemia. It is interesting to note that in glucose fed rats, the chloroform extract of Leucas lavandulaefolia (0.25 g/kg) effectively prevented increase in blood glucose levels without inducing a hypoglycemic state. In conclusion, the chloroform extract of Leucas lavandulaefolia flowers, which was found to exhibit a hypoglycemic activity in Alloxan induced diabetic rat, was more effective than glybenclamide. Studies are in progress in our laboratory to elucidate in detail the mechanism of action of these drugs at the cellular and molecular levels. Flavonoids are known to have bioactive antidiabetic principles. [20] Flavonoid glycoside is assumed to be the compound responsible for the lowering of glucose.

   References Top

1.Kirtikar KR, Basu BD. Indian medicinal plants. 2 nd ed. Dehradun: Internal Book Distributors; 1975. Vol 3, p. 2016.  Back to cited text no. 1      
2.Anonymous. The Wealth of India, raw materials. New Delhi: C.S.I.R; 1962. Vol 3, p. 79.  Back to cited text no. 2      
3.Chopra RN, Handa KL. Indigenous drugs of India. Calcutta: U. N. Dhur and Sons Pvt. Ltd; 1958. p. 606.  Back to cited text no. 3      
4.Chandrashekar KS, Arun BJ, Satyanarayana D, Subramanyam EVS. Flavonoid glycoside from Leucas lavandulaefolia (Rees) aerial parts. Indian J Chem B 2006;45: 1968-9.  Back to cited text no. 4      
5.Kakali S, Pulok M, Das J, Sushash C, Pal M, Saha BP. Hypoglycemic activity of Leucas lavandulaefolia Rees in streptozocin-induced diabetic rats. Phytother Res 1998;6:463-6.  Back to cited text no. 5      
6.Larner J. Insulin and oral hypoglycaemic drugs, Glucagon. In: Gilman AG, Goodman LS, Rall TW, Murad F, editors. The pharmacological basic of therapeutics.7th ed. New York: MacMillan; 1985. p. 1490-516.  Back to cited text no. 6      
7.Jain SR. Hypoglycaemic principle in Musa sapientum and its isolation. Planta Med 1968;16: 43.   Back to cited text no. 7      
8.Gupta NP, Solis NG, Avella ME, Sanchez E. Hypoglycaemic activity of Neuroleena lobata. J Ethnopharmacol 1984;10:323-7.   Back to cited text no. 8      
9.Sasaki T, Matsy S, Sonae A. Effect of acetic acid concentration on the colour reaction in the o-toluidine boric acid method for blood glucose estimation. Rinsho Kagaku 1972;1:346-53.   Back to cited text no. 9      
10.Drabkin DL, Austin JM. Spectrophotometric constants for common haemoglobin deravitaves in human, dog and rabbit blood. J Biol Chem 1932; 98: 719-33.   Back to cited text no. 10      
11.Sudhakar Nayak S, Pattabiraman TN. A new colorimetric method for estimation of glycosylated haemoglobin. Clin ChemActa 1981;109:267-4.   Back to cited text no. 11      
12.Waynforth BH. Injection techniques, experimental and surgical techniques in the rat. London: Academic Press; 1980. p. 3-61.   Back to cited text no. 12      
13.Whittington KB, Solomon S, Lu N. Islet allograft in the cryptochd testes of spontaneousl diabetic BBI word p rats: Response, glipizide and arginine. Endocrinology 1991;128:2671-7.  Back to cited text no. 13      
14.Goth MD. Medical pharmacology. 9 th ed. Mosby, Saint Louis, MO: 1985. p. 471-80.  Back to cited text no. 14      
15.Farjou IB, Al-Ani M, Guirgos SV. Lowering of blood glucose in diabetic rabbits by Artemisia extract. J Faculty Med Univ Baghdad 1987;29:137-1.   Back to cited text no. 15      
16.Al-Lami A, Farjou IB. Effect of feeding Artemisia herba alba on glucokinase and ATPase activity in normal and diabetic rabbits. J Faculty Med Univ Baghdad 1990;32:13-20.   Back to cited text no. 16      
17.Koeing R, Peterson CM, Jones RL, Sandik C, Lehrman M, Cerami A. Correlation of glucose regulation and hemoglobin Aic in diabetes mellitus. N Engl J Med 1976;295:417-20.   Back to cited text no. 17      
18.Jackson RL, Hess RL, England JD. Haemoglobin Aic values in children with over diabetes maintained in varying degree of control. Diabetes Care 1979;2:391-5.  Back to cited text no. 18      
19.Al-yassin D, Ibrahim K. A minor haemoglobin fraction and the level of fasting blood glucose. J Faculty Med Univ Baghdad 1981;23:373-80.  Back to cited text no. 19      
20.Kameshwara BR, Renuka PS, Rajasekhar MD, Nagaraju N. Antidiabetic activity of Terminalia pallida fruit in alloxan induced diabetic rats. J Ethnopharmacol 2003;85:169-72.  Back to cited text no. 20      


  [Table 1], [Table 2]


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