Chemical Group Profiling, In Vitro and In Silico Evaluation of Aristolochia ringens on α-Amylase and α-Glucosidase Activity.

Diabetes mellitus (DM) has become a global scourge, and there is a continuous search for novel compounds as viable alternatives to synthetic drugs which are often accompanied by severe adverse effects. Aristolochia ringens is among the scientifically implicated botanicals effective in the management of several degenerative diseases including DM. The current study evaluated the inhibitory mechanism(s) of root extract of A. ringens on α-amylase and α-glucosidase in vitro and in silico, while its constituents were characterized using liquid chromatography-mass spectrometric technique. The extract had concentration-dependent inhibitory effect on the study enzymes, and the inhibition compared well with that of standard drug (acarbose) with respective IC50 values of 0.67 mg/mL (α-amylase) and 0.57 mg/mL (α-glucosidase) compared with that of the extract (0.63 and 0.54 mg/mL). The extract competitively and uncompetitively inhibited α-amylase and α-glucosidase, respectively. Of the identified compounds, dianoside G (-12.4, -12.5 kcal/mol) and trilobine (-10.0, -10.0 kcal/mol) had significant interactions with α-amylase and α-glucosidase, respectively, while magnoflorine and asiatic acid also interacted keenly with both enzymes, with quercetin 3-O-glucuronide and strictosidine showing better affinity towards α-glucosidase. These observations are suggestive of involvement of these compounds as probable ligands contributing to antidiabetic potential of the extract. While studies are underway to demystify the yet to be identified compounds in the extract, the data presented have lent scientific credence to the acclaimed in vivo antidiabetic potential of the extract and suggested it as a viable source of oral hypoglycaemic agent.

Toxicity assessment of sub-acute and sub-chronic oral administration and diuretic potential of aqueous extract of Hibiscus sabdariffa calyces.

BACKGROUND: Food and herbal usage of Hibiscus sabdariffa (HS) is attaining improved global relevance and acceptance without recourse to its potential toxic effects. This study investigated the safety profile of acute, sub-acute, sub-chronic administrations and diuretic potential of aqueous extract of Hibiscus sabdariffa calyces (AEHSC). METHOD: Acute oral toxicity, sub-acute and sub-chronic toxicity as well as diuretic studies were carried out on HS. A total of 20 Wistar rats were used for each toxicity study and assigned into four groups of five rats. The extract was administered as a single daily dose of 125, 250 and 500 mg/kg body weight (bwt) for 28 and 90 days respectively. To evaluate diuretic activity, 25 rats were divided into five groups of five rats and administered normal saline, hydrochlorothiazide 10 mg/kg, AEHSC 67.5, 125 and 250 mg/kg via the oral route. Urine sample was collected after 18 h, volume measured and concentration of electrolytes analyzed. The hematological and biochemical parameters were evaluated as well as the histopathology of kidney and liver. RESULTS: The acute oral toxicity was found to be >2000 mg/kg. AEHSC did not alter concentration of WBC, MCV, MCHC, lymphocyte as well as total and direct bilirubin in the sub-acute study. However, AEHSC significantly (p < 0.05) increased total protein, albumin, globulin, Na+, Cl-, HCO3 - and platelet levels, while levels of uric acid, creatinine, K+, RBC, Hb, total cholesterol, triglycerides, LDL-C, HDL-C and atherogenic index were decreased significantly (p < 0.05). In the sub-chronic study, AEHSC significantly (p < 0.05) increased the levels of globulin, urea, creatinine, MCH and atherogenic index. The concentrations of uric acid, WBC, platelets and HDL-C were significantly (p < 0.05) decreased. In both the sub-acute and sub-chronic studies, activities of ALP, ALT, AST, GGT and LDH in selected organs were altered without significant increase (P < 0.05) in activity of these enzymes in the serum. The AEHSC at all the doses showed remarkable diuretic activity during 18 h period comparable to hydrochlorothiazide. The extract also showed a non-dose-dependent increase in excretion of electrolytes. Histological analysis of sections of the liver and kidney for both sub-acute and sub-chronic studies showed normal histology comparable to the control group. CONCLUSION: This study revealed AEHSC has some toxic effects in rats on sub-chronic administration. In addition, the extracts produced a significant diuretic activity. Hence, prolonged oral consumption of the extract may not be recommended.

Chemopreventive and remediation effect of Hydrocotyl bonariensis Comm. Ex Lam (Apiaceae) leave extract in galactose-induced cataract.

ETHNOPHARMACOLOGICAL RELEVANCE: Hydrocotyl bonariensis Comm. Ex Lam (Apiaceae) is being widely used in Western Nigeria in treating various symptoms of ophthalmic diseases; however scientific data in support of this medicinal use have not been reported. AIM OF THE STUDY: This study, investigated the efficacy of Hydrocotyl bonariensis leave extract in offering protection against experimental cataract and also examined its remediation effect when administered after cataract onset. MATERIALS AND METHODS: Weanling albino rats fed with 30% galactose diet were used in the study. Mechanisms of action of the extract were investigated by measuring the degree of lens peroxidation, lens antioxidant status and lens protein concentration. Severity of cataract was determined by measuring the cataract index. RESULTS: The extract at 500 mg kg(-1) reduced cataract index significantly and also reduced cataract progression when administered after cataract onset. Administration of this dosage also significantly reduced the degree of lens peroxidation, increased the level of reduced glutathione (GSH) and the lens catalase and superoxide dismutase activity. The extract also prevents protein insolubilization. Administration of the extract at 1000 mg kg(-1) reduced cataract index and lens peroxidation but did not increase the antioxidant status significantly. Administration of the extract after cataract onset reduced cataract index, moderately increased percentage soluble protein above the value prior to the arrest of hypergalactosemia but did not increase the antioxidant status. CONCLUSION: Our study suggests that Hydrocotyl bonariensis protects against galactose-induced cataract, and that administration of the extract after cataract onset reduced cataract progression but did not reverse cataractogenesis.

Protective effect of Garcinia kola (kolaviron) extract on predisposition of rats to cardiovascular diseases following separate administration of amodiaquine and artesunate.

This study was carried out to investigate the cardiovascular effect of administration of antimalarial drugs amodiaquine and artesunate and the efficacy of Garcinia kola extract (kolaviron) in protecting against such possible effect. Thirty (30) adult male albino rats divided into six (6) groups were used in this study. Groups D, E and F were treated with 100 mg/Kg b. w. of the extract twice daily for the first one week and 200 mg/Kg b. w./day for the subsequent three (3) weeks. Amodiaquine (10 mg/Kg b. w./day) was administered orally for four (4) days into rats in groups A and E while rats in groups B and F were treated with artesunate (5 mg/Kg b. w./day) for four (4) days. Group C rats (normal control) were treated with normal saline. All the rats were sacrificed after four (4) weeks treatment period. Blood was withdrawn by cardiac puncture while the liver, kidney, stomach and heart were removed, cleansed and weighed. Total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides were measured in the serum, while total fibrinogen, platelet count, red blood cell and white blood cell count were measured in the whole blood. The artherogenic and coronary risk index were also determined. Results indicate that both amodiaquine and artesunate predispose to cardiovascular disease, however the effect was more pronounced with artesunate than amodiaquine. The result also suggests that both drugs could increase the risk of coronary and artherogenic diseases and that Garcinia kola do not prevent the cardiotoxicity and coronary risk effect.

Prevalence of Hypercalcaemia in Shagamu; Ogun State; Nigeria

Nine hundred and two (902) patients were randomly selected from the patients that reported in the Clinical Biochemistry Laboratory of Olabisi Onabanjo University Teaching Hospital; Shagamu; Nigeria. The period of study was 2 years. The prevalence of hypercalcaemia was found to be 3.79

Combined effect of chloroquine and insulin administration on some biochemical parameters in rats placed on high fat and calcium diet.

Effect of combined administration of Insulin and Chloroquine on fasting blood glucose, total protein, creatinine and uric acid concentration were investigated in rats placed on diets high in fat and calcium (SP diet). Thirty-six (36) rats (grouped into six) were placed on different treatment: Grams A and B were fed with NP (normal diet) and SP diet respectively; Group C was placed on NP diet and injected intramuscularly with 100 microg insulin per day; Group D was placed on SP diet and also injected with 100 microg insulin per day; Group E was placed on SP diet and injected with both insulin (100 microg/day) and chloroquine (20mg/Kg thrice weekly); Group F was placed on SP diet and injected with chloroquine (20mg/Kg) thrice weekly. After 15 weeks of treatment, a significantly reduced concentration of glucose was observed in groups injected with insulin and those injected with insulin and chloroquine together (compared with the control groups, A and B). The serum total protein and uric acid level were however not significantly different in all the rats. Serum creatinine was also observed to be significantly lowered in the rats treated with insulin. The results of this study thus suggest that insulin and chloroquine administration may result in reduced blood glucose level (hypoglycemia). It also suggests that insulin and chloroquine administration may further effect an improved kidney function.

Antihypertensive effect of roselle (Hibiscus sabdariffa) calyx infusion in spontaneously hypertensive rats and a comparison of its toxicity with that in Wistar rats.

The LD(50) of roselle calyx extract and its effect on blood pressure were determined. The LD(50) was found to be above 5000 mg kg(-1). Roselle calyx infusion was found to lower significantly (p<0.05) both systolic and diastolic pressure in spontaneously hypertensive and normotensive Wistar-Kyoto rats at tested doses of 500 and 1000 mg kg(-1) body weight. The reduction in blood pressure in both groups was positively correlated with weight. Continuous consumption of the infusion at 1000 mg kg(-1) was discovered to lead to sudden death in spontaneously hypertensive rats but not in Wistar-Kyoto rats. Water intake was not significantly different (p>0.05) in the control groups of the two strains of rats used, neither was there a significant difference in their urine output. The water intake in the treated spontaneously hypertensive and normotensive rats was not different from the corresponding control groups. However the urine output of the treated spontaneously hypertensive rats was significantly higher. A significant decrease in serum creatinine, cholesterol, and glucose in the treated rats compared with the control as well as a significant increase in serum uric acid was observed. The serum proteins (albumin and total protein) in the treated rats when compared with the control groups was not changed significantly.