ABSTRACT
The cytotoxic and apoptotic potentials of four commercial tinctures of S. baicalensis (SB1, SB2, SB3 and SB4) were investigated on three human lung cancer cells SK-MES-1, SK-LU-1 and A549. The number of cells that survived treatment with different concentrations of the tincture in 24, 48 and 72 hours was quantified by the colorimetric MTT assay. Acridine orange/ Propidium iodide dye exclusion assay was used to test for apoptosis in 24 and 48 hours at 200 μg/ml concentration of the tinctures. All the tinctures except SB4 showed a dose and time-dependent effect on the cancer cells. The minimum cytotoxic concentration of SB1, SB2, and SB3 sample tinctures on the SK-MES-1 and SK-LU-1 cells was approximately 100 μg/ml in 48 hours. 100 μg/ml of SB1 and SB2 tinctures have significant (p<0.05) cytotoxic activity on the SK-MES-1 cells in 72 hours. The A549 cells were the least sensitive to toxicity as significant effect on growth inhibition was not seen until 300 μg/ml. Of all the tinctures, only the SB1 showed significant (p<0.05) cytotoxic activity on nontransforming normal dividing FS5 cells, pointing to the possibility of a non-specific side effect at 400 μg/ml. Estimating duration of effect from the time taken to reverse cell growth inhibition, SB1 tinctures had the longest effect of up to 72 hours on the SKMES- 1 cells. Other tinctures showed significant (p<0.05) time-dependdent inhibition of cell growth up to at least 48 hours. Typical apoptotic morphological changes were observed with SB1, SB2 and SB3 tinctures in 24 hours but were more pronounced after 48 hours. The tinctures showed variable characteristics in terms of their dose response, duration of action and potential side effects. There is therefore an urgent need to standardize and regulate the manufacture of herbal formulations and establish a scientific evidence base on the use of commercial formulations of S. baicalensis.
ABSTRACT
Rural dwellers in Nigeria often resort to herbal remedy and dietary control in the treatment of diabetes mellitus (DM). This work was undertaken to provide the rationale for the use of the leaves of Gogronema latifolium as a traditional antidiabetic agent. Methanol extract (ME) of the leaves of G. latifolium was prepared by soxhlet extraction while the aqueous extract (AE) was prepared by cold maceration. The methanol extract was separated into fractions by column chromatography to yield methanol fraction (MF), n-hexane fraction (HF) and chloroform fraction (CF).The extract and the fractions were evaluated for antidiabetic effect in alloxan-induced diabetes in rats. The blood sugar levels were assayed as indices of diabetes. The phytochemical analyses of the extracts and fractions as well as the LD50 of the ME were determined. The results indicated that intraperitoneal injection of AE, ME, CF, HF, and MF, (200-800 mg/kg/day) exhibited a significant (P<0.05) anti-diabetic effect by ameliorating alloxan-induced increase in blood sugar. Antidiabetic potency of the extracts and fractions was in the order; MF> ME> AE>HF>CF. Phytochemical analysis of the extracts and fractions indicated high concentration of proteins, flavonoids, saponins, alkaloids, terpenoids, and steroids while tannins, reducing sugar and acidic compounds were absent. The LD50 of the methanol extract was calculated to be 900mg/kg. The results of this study lead credence to the use of G. latifolium in the management of diabetes mellitus.