As Nigeria joins the rest of the world today to mark the World Diabetes Day, CHUKWUMA MUANYA reports that more recent studies are validating the folklore uses of local plants and spices such as bitter leaf, scent leaf and Gongronema latifolium (Utazi in Ibo) among others in the management of diabetes.
A STUDY published in April 2013 edition of Journal of natural pharmaceuticals found that treatment of alloxan diabetic rats with polyherbal combinations of Vernonia amygdalina (bitter leaf), Gongronema latifolium (Utazi in Ibo), and Ocimum gratissimum (scent leaf) caused significant reductions in the blood glucose level (BGL) of the diabetic rats both in acute and prolonged treatment (two weeks).
The University of Uyo researchers found that the activities of various combined extracts were comparable and more pronounced than that of glibenclamide and compared to that of glibenclamide in the prolonged study. The anti-diabetic activities of the various herbal combinations confirm the folkloric use of these polyherbal remedies.
The researchers concluded, “the finding of this study confirms the efficacy of the various polyherbal combinations used traditionally by herbalists of Ibibio tribe of Akwa Ibom State, Nigeria for the management of diabetes which are of advantage. Further studies into polyherbal combinations used in the management of diabetes are encouraged to support the advantage of polytherapy.â€
The study is titled: “Antidiabetic study of combined extracts of Vernonia amygdalina, Ocimum gratissimum, and Gongronema latifolium on alloxan-induced diabetic rats.â€
Herbal products are often used as combinations of some herbs for the treatment of diseases in traditional medicine.
The various polyherbal combinations of V. amygdalina, G. latifolium, and O. gratissimum (100 mg/kg each) were evaluated for anti-diabetic activity in alloxan induced diabetic rats. The anti-diabetic activities during acute and prolonged studies were investigated. Glibenclamide, 10 mg/kg, was used as positive control. Blood glucose level (BGL) was measured at intervals by using glucometer.
According to the researchers, ethnomedicine is an integral part of the culture of people of Akwa Ibom State and about 75 per cent of the people rely on traditional medicine for health-care delivery. Majority of the people still patronise herbal remedies despite the availability of orthodox medicine in their management of some diseases and ailments. Besides, polyherbal therapy (practice) is a common practice in the Ibibio traditional medicine, as combination of roots/leaves and stem barks of various plants are often use in the treatment of a single disease.
Moreover, polyherbal therapy is said to be a current pharmacological principle having the advantage of producing maximum efficacy with minimum side effects.
According to Tiwari and Rao, polyherbal therapies have the synergy, potentiative, agonistic/antagonistic pharmacological agents within themselves, that work together in a dynamic way to produce therapeutic efficacy with minimum side-effects.
Diabetes is one of the diseases treated by herbalist of Ibibio tribe using polyherbal combinations.
Ethnobotanical information from some traditional medicine practioners revealed that Vernonia amygdalina, Ocimum gratissimum, and Gongronema latifolium constitute bulk of the many polyherbal combinations use in the area for the treatment of diabetes.
Ajibesin et al., in their ethnobotanical survey of Akwa Ibom State documented the three plants as anti-diabetic remedies used in the region. Several workers have reported on the anti-diabetic/hypoglycemic activities V. amygdalina, O. gratissimum, and G. latifolium.
The researchers investigated the efficacy of the different combinations of the three plants on alloxan induced diabetic rats as used in ethnomedical therapy of diabetes in Akwa Ibom State to ascertain their potency.
The researchers wrote: “The anti-diabetic effects of different combinations of leaf extracts of G. latifolium, V. amygdalina and O. gratissimum use in polyherbal therapy of diabetes were evaluated in this study.
“The results showed that the various combinations: G. latifolium and O. gratissimum; G. latifolium and V. amygdalina; G. latifolium, V. amygdalina, and O. gratissimum; and O. gratissimum and V. amygdalina, had significant antihyperglycemic activity which was more than that of glibenclamide (in acute study) and comparable in effect to glibenclamide (during prolonged study). Within the treatment period (14 days) the various combined extracts’ effects demonstrated synergism as the extracts appeared to complement each other thereby reducing the BGL of the diabetic rats to normal.
“This was clearly demonstrated in the group administered combination of the three extracts during prolonged study. The results of this study collaborates the advantages of polyherbal articulated by Tiwari and Rao.
“Furthermore, the results of this study support earlier reports of anti-diabetic potentials of these plants. Different mechanism of actions of anti-diabetic plants have been proposed such as potentiation of insulin effect either by increasing the pancreatic secretion of insulin from the cells of Islets of Langerhans or its release from bound insulin, inhibition of hepatic glucose production, inhibition of intestinal glucose absorption, or correction of insulin resistance.
“These three extracts may have exerted their anti-diabetic effects by utilising one or more of the above mechanisms. A combination of these mechanisms could have resulted in the significant anti-diabetic activity observed in this study, which is likely to be sustained and better than that of a single extract.
“Moreover, sulfonyl ureas, including glibenclamide, produce hypoglycemia in normal as well as diabetic animals by stimulating the pancreatic β-cells to release more insulin. These extracts’ combinations maybe working through a similar mechanism like glibenclamide as the results gotten from the combinations and glibenclamide were comparable.
“Secondary metabolites have been reported to be involved in anti-diabetic activity of many plants. Reports have shown that these plants have various phytochemical constituents in common such as alkaloids, steroids, glycosides, saponins, tannins, terpenes, and flavonoids.
“In addition to anti-diabetic properties of these plants, each of the plants has been reported of different activities geared towards alleviation of complications usually associated with diabetes. For example, V. amygdalina has been reported to be hepatoprotective and antioxidant, G. latifolium, antioxidant, hepatoprotective and hypolipidaemic, O. gratissimum, antioxidant and others.
“All these activities complements the anti-diabetic activities of these plants and are advantageous to antagonize and resolve any side effects any of the extracts could have posed. The effectiveness of polyherbal combination has been reported widely. V. amygdalina and Azadirachta indica (Neem tree or Dogonyaro) combination has been shown to be very effective.â€
Source: The Nigerian Guardian
