PROTECTIVE EFFECT OF ETHANOLIC EXTRACT OF SOLANUM NIGRUM ON THE BLOOD SUGAR OF ALBINO RATS

PROTECTIVE EFFECT OF ETHANOLIC EXTRACT OF SOLANUM NIGRUM ON THE BLOOD SUGAR OF ALBINO RATS

Nazoora Saleh Aali*, Kusum Singh, Md. Iqbal Khan and Sapna Rani

Department of Zoology, Institute of Basic Sciences, Bundelkhand University, Jhansi (UP), India

ABSTRACT

In recent times, focus on plant research has increased all over the world and a large body of evidence has collected to show immense potential of medicinal plants used in various traditional systems. Solanum nigrum (commonly called Makoi) is also a medicinal plant. A dietary intake of Solanum nigrum supplies our body with nutrients that offer protection against numerous diseases. All parts of this plant are used in the traditional medicine as a remedy for treating various diseases like, cough, cold, asthma, skin diseases and liver problem. Now a day, Diabetes mellitus has become a real problem of public health in developing countries. This is a metabolic disorder characterized by disarrangements in carbohydrate, protein and fat metabolism caused by the complete or relative insufficiency of insulin secretion and /or action. This is due to defective or deficient insulin secretary response. This results into impaired glucose use, which is a characteristic feature of diabetes mellitus i.e. resultant hyperglycemia. Elevated blood glucose level causes dehydration of the tissue cells as glucose does not diffuse easily through the pores of cell membrane and increased osmotic pressure. Present investigation is therefore designed to determine the effect of crude ethanolic extract of S. nigrum on blood sugar of albino rat  after daily oral administration of dose  at the level of 250mg/kg b. wt. for five and seven days respectively. It was noticed that the chronic administration for longer duration leads to significant decrease in blood sugar compared to control. Thus it can be concluded that Solanum nigrum also has the anti- diabetic property.

INTRODUCTION: In recent times, focus on plant research has increased all over the world and a large body of evidence has collected to show immense potential of medicinal plants used in various traditional systems. Solanum nigrum is also a medicinal plant. It has been used widely as medicinal and food plants despite their reputation for being poisonous. The unripe fruit of S. nigrum contain the highest concentration of toxin particularly Solanine ¹. The level of toxin in the berries is greatly reduced by ripening ^{2, 3}. The ripe berries are eaten raw as fruits and are used in pies and preservative in many regions of the world. All parts of this plant are used in the traditional medicine as a remedy for treating various diseases like, cough, cold, asthma, skin diseases and liver problem.

Now a day, Diabetes mellitus has become a real problem of public health in developing countries ⁴. It is actually a chronic disorders related to abnormality of carbohydrate, fat and protein metabolism. This is due to defective or deficient insulin secretary response. This results into impaired glucose use, which is a characteristic feature of diabetes mellitus i.e. resultant hyperglycemia.

Elevated blood glucose level causes dehydration of the tissue cells as glucose does not diffuse easily through the pores of cell membrane and increased osmotic pressure. Present investigation is therefore designed to determine the effect of crude ethanolic extract of S. nigrum on blood sugar of albino rat  after daily oral administration of dose  at the level of 250mg/kg b. wt. for five and seven days respectively. It was noticed that the chronic administration for longer duration leads to significant decrease in blood sugar compared to control. 

MATERIALS AND METHODS:

Collection and Extraction of Plant Material           : Whole plant of Solanum nigrum except root was collected locally from the Bundelkhand region and dried in shade till total moisture is removed from the plant. These air dried plants were powdered in an electric grinder. The extraction process was done with the help of Soxhlet apparatus. Solvent was ethanol. Extracts were kept in desiccators for the removal of remaining moisture.

Animals: Mature albino rats of Sprague- Dawley strain weighing about 150-200gm were obtained from the defense research laboratories, Gwalior and were used for study. They were fed with standard rat pellet diet (Amrut, Delhi) and water ad- libitum and maintained under standard laboratories conditions temperature 24-280c,relative humidity 60- 70%. The study was permitted by the Institutional animal ethics committee (IAEC) of Bundelkhand University, Jhansi and with permission from committee for the purpose of control and supervision of experiments on animals (716/o2/9/CPCSEA).

Experimental Protocol: A dose at a concentration of 250mg/kg b. wt. was prepared. Animals were divided into two groups each having 5 rats. Group I rats received normal standard diets and vehicle only. Group II is experimental, which receive different dose of solanum nigrum extract.

Blood Sampling: The rats were fasted over night and sacrificed under light anesthesia (ether inhalation) at the end of 5 and 7 days after treatment. Blood samples were collected from the retro- orbital plexus of treated rats. The samples were taken in to tubes with anticoagulant. From this sample blood sugar was estimated by a standard method of Asatoor and King ⁵.

RESULT AND DISCUSSION: The blood sugar levels of the control rats remained almost static during 7 days (Table 1). When oral dose (250mg/kg b. wt.) of Solanum nigrum was administered daily for 5 days and 7 days, there was a successive decrease in the blood sugar level.

TABLE 1: EFFECT OF DAILY ADMINISTRATION OF S.NIGRUM EXTRACT ON THE BLOOD SUGAR (MG/DL OF BLOOD) OF ADULT ALBINO RATS

Values are expressed as mean + S.E.  P<0.05

Medicinal plant extracts have been valuable anti-diabetic agents and may involve one or more active components responsible for blood glucose reduction ^{6, 7}. The preliminary phytochemical screening of these fractions of S. nigrum aqueous extract revealed the presence of alkaloids and solanines which may be responsible for the observed antidiabetic effects of these fractions by possibly stimulating insulin release from pancreatic beta cells. In consonant with this study, some researchers reported that alcoholic extract of leaves of Cinnamomum tamala (Bayberry) produced hypoglycemic activity in alloxan induced diabetic rats when administered orally for two weeks at a dose of 250 mg/kg ⁸.

Mohammad et.al.⁹ has earlier reported the hypoglycemic activity of aqueous extract of G. lucidum in Wistar rats. Over 400 medicinal plants are available globally for the medication of diabetes mellitus, with a few having been subjected to scientific authentication to ascertain their effectiveness as anti-diabetic agents ¹⁰. Substances with hypoglycemic properties would be effective in the management of diabetes mellitus ¹¹. This protective effect of the extract may be mainly attributed to steroidal saponins, namely nigrumin I and II, which may possess antioxidant and detoxifying effects. Therefore, a dietary intake of Solanum nigrum fruits supplies our body with nutrients that offer protection against numerous diseases. Further studies are warranted to elucidate the mechanisms of action and to explore its medicinal value.

REFERENCES:

1. Ong HC: Sayuran Khasiat Makanan dan Ubatan: Utusan Publication: Distributors sdn.Bhd:Fakulti Sains, University Malaya. (2003): 92-93.
2. Edmonds JM, Chweya JA: Black nightshades: Solanum nigrum and related species. Promoting the conservation and use of underutilized and neglected crops15.Gatersleben: Institute of plants Genetics and crop plants research Rome: International Plant Genetic Resources Institute. (1997): 113p.
3. Fernald ML, Kinsey AC: Edible wilds plants of Eastern North America. Revised by R.c.Rollins New York: Harper and Row. (1958): 452 p.
4. Mohammed A, Adelaiye AB, Bakari AG, Mabrouk MA: Anti- diabetic and some haematological effects of ethylacetate and n-butanol fractions of Ganoderma lucidum aqueous extract in alloxan - induced diabetic wistar rats. International Journal of Medicine and Medical Sciences, (2009):  Vol 1. (12): 530-535.
5. Asatoor AM, King E: In practical clinical biochemistry Vorley H.ed. Gulab vazirani Publication,India for Arnold. Heinemann, 4th edition, (1969):
6. Farnsworth RN: Review on Biological and Phytochemical screening of plants. J. Pharm. Sci. (1995); 55: 225-276.
7. Grover JK, Yadav S, Vats V: Medicinal plants of India with hypoglycemic potentials. J. Ethnopharmacol. (2002); 81: 81-100.
8. Kar A, Choudhary BK, Bandyopadhyay NG: Comparative evaluation of hypoglycaemic activity of some Indian medicinal plants in alloxan diabetic rats. J. Ethnopharmacol. (2003); 84: 105-108.
9. Mohammed A, Adelaiye AB, Abubakar MS, Abdurahman EM: Effects of aqueous extract of Ganoderma lucidum on blood glucose levels of normoglycemic and Alloxan-induced diabetic Wistar rats. J. Med. Plant Res. (2007); 1(2): 34-37.
10. Onoagbe IO, Esekheigbe A: Studies on the anti-diabetic properties of Uvaria Chamae in streptozotocin-induced diabetic rabbits. Biokemistri. (1999); 9: 79-84.
11. Young NS, Maciejewski J: The pathophysiology of Acquired Aplastic anemia. N. Eng. J. Med. (1997); 336: 1365.
    

    ---