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BackgroundPathophysiological investigation of disease in a suitable animal model is a classical approach towards development of a credible therapeutic strategy. This study examined appropriate insulin level in selecting animal model for type 2 diabetes (T2D) studies.MethodAlbino Wistar rats (150-200g) were divided into two groups fed with commercially available normal-diet-feed (NDF) and water or fortified diet feed (FDF) (10g NDF per gram of margarine) with 20% fructose solution as drinking water. After 6 weeks of dietary regimen both groups were divided into 5 sub-groups and injected intraperitoneally with a graded dose of streptozotocin (STZ) (0, 25, 35, 45 & 55mg/kg bw.).ResultThe result showed that the FDF-fed rats increased significantly in body weight, basal serum insulin, total cholesterol, triglycerides and blood glucose levels as compared to NDF-fed rats. Ten days post STZ induction, the groups treated with STZ (45 & 55 mg/kg) developed frank hyperglycaemia with < 46.8% serum insulin, a severe deficiency typical of diabetes type 1. The NDF25 and NDF35 groups with 75.7% and 64.4% serum insulin respectively presented relative normoglycemia, whereas the FDF35 (85.8% serum insulin) were notably hyperglycaemia (>300 mg/dL) throughout the 6weeks post diabetes confirmation. These FDF35 rats were sensitive to glibenclamide, metformin and pioglitazone in lowering hyperglycaemia, hypertriglyceridemia and hypercholesterolemiaConclusionThe hyperglycaemia stability of the FDF35 rats (85.5% insulin) together with their sensitivity to 3 different hypoglycaemic drugs strongly suggests their suitability as a non-genetic model of T2D. Hence the study shows that circulating serum insulin ≥ 85.8% with overt hyperglycaemia may be utilized as the benchmark in selecting rat models for T2D studies.

Background: Ocimum gratissimum (OG) is used in the traditional management of diabetes in Nigeria. This study investigated the anti-diabetic potential of OG leaf fractions (OGLF) in a rat model of Type-2 diabetes (T2D). Methods: Methanol crude extract of OG leaf was fractionated with solvents of increasing order of polarity (n-hexane, chloroform, ethyl-acetate, n-butanol and water). The anti-diabetic potential of the fractions was evaluated in vivo. T2D was induced in Albino Wistar rats and treated with OGLF. Results: The T2D rats showed significant elevation in serum levels of fasting blood glucose (FBG), liver and kidney function biomarkers. At 4-week of intervention with OGLF, the untreated diabetic control group maintained severe hyperglycaemia in the presence of 61.7% serum insulin, 17.3% pancreatic β-cell function (HOMA-β) and 51.5% Insulin sensitivity. The glucose tolerance ability was enhanced in the n-butanol-fraction (OGb) treated group. With 74.8% available serum insulin and 38.6% improvement in insulin sensitivity, the OGb treated group had a 63.5% reduction in FBG and it was found to be most effective as it ameliorates a majority of the changes caused in the studied parameters in diabetic rats. Conclusions: The data from this study suggest that OGb fraction is a potential candidate for the development of an effective drug for the management of T2D.

Aim: The purpose of this pilot study was to genetically identify and characterize Coxiella burnetii from Amblyomma varigatum ticks collected on cattle in North central Nigeria. Materials and Methods:A total of 40 partially fed ticks morphologically identified as adult A. variegatum ticks collected from cattle owned by Fulani pastoralists were evaluated for the presence of C. burnetii using PCR, cloning, and sequencing of the heat shock polypeptide gene htpB.Results: C. burnetii DNA was detected in 10 (25%) of the ticks analyzed. Sequences for the C. burnetii gene htpB detected in our samples had 99-100% identity to all other C. burnetii that have been described and that are deposited in the GenBank database. Phylogenetic analysis using neighbor-joining method indicates the clustering of C. burnetii sequences from our study areas with those collected from Oyo state, South-western Nigeria and Spain. Conclusion:This study shows a high infection rate of C. burnetii in A. variegatum ticks in the study areas. Phylogenetic inferences indicates that the strain of C. burnetii found in the North central states of Plateau and Nasarawa were same as those previously reported in the South western state of Oyo. The presence of this pathogen in naturally occurring A. variegatum tick populations could present an additional risk of Q-fever disease to humans, especially to the pastoralists that are closely associated with their animals and are easily exposed to tick bites. Therefore, further studies are needed to assess the competence of A. variegatum ticks as vectors of C. burnetii pathogens.

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