Eliud MN NjagiNicholas . K. GikonyoMathew P. NgugiKimani, Njoroge Gideon2021-09-272021-09-272021http://ir-library.ku.ac.ke/handle/123456789/22666A Thesis Submitted in Fulfillment of the Requirements for the Award of the Degree of Doctor of Philosophy (Medical Biochemistry) in the School of Pure and Applied Sciences of Kenyatta University, May 2021The primary goal in the management of diabetes mellitus is to realize normoglycemia as much as possible. In conventional medicine, oral insulin secretagogues and parenteral insulin are used as hypoglycemic agents. However, they have known side effects such as insidious hypoglycemia, lactic acidosis, liver injury and neurological deficit. On the other hand, numerous phytotherapeutics that have been used in traditional, complimentary or alternative medicine for the treatment of diabetes have not been evaluated for their effectiveness and or their toxicity effects. The objective of this study was to evaluate the in vivo glycemic and toxicity effects of aqueous extracts of Triticum aestivum, Hordeum vulgare, Urtica massaica and Cynanchum viminale. Diabetes was induced by intraperitoneally administering 10% alloxan monohydrate into Wistar rats. Rats with fasting blood glucose levels above 200 mg/L 72 hr post alloxan administration were used in this study to evaluate efficacy of doses of aqueous plants extracts against glibenclamide and insulin as reference drugs. Toxicity studies were done by oral or intraperitoneal administration of doses of aqueous plant extracts for 28 days. The rats were euthenized and blood taken for hematological and biochemical studies. Gross and relative organ weights were taken. Presence of minerals, phytonutrients and phytochemicals in the plants extracts was also established. A p < 0.05 was consindered statistically significant. The results obtained in this study indicates that both orally and intraperitoneally administered aqueous plants extracts used in this study exhibited varying degrees of blood glucose lowering effects. When orally administered, all the plants extracts did not have significant different effect on cardiac and pancreatic systems, liver and kidneys relative to the control. Significant variations in some gross organ and relative organ weights between the extracts administered and control rats though observed were not supported by haematological or biochemical changes hence not pathologically associated. However, statistically significant effects were recorded when some of the plants extracts were intraperitoneally administered compared to the controls. Flavonoids, alkaloids, saponins, steroids, cardiac glycosides, minerals and vitamins were found to be present in the aqueous plants extracts. In conclusion, the aqueous plants extracts evaluated in this study have demonstrated blood glucose reduction properties and validates their use in control and mitigation of diabetes mellitus. Further, results obtained on phytonutrients and bioactive secondary metaboloites assay indicate the presence of various functional groups. The synergistic activities of the various compounds present in the aqueous plants extracts in this study are attributable to the plant’s observed blood glucose lowering effects. When orally taken, none of the logarithmic doses of either of the plants extracts demonstrated any toxicity effects while some of the plants extracts exhibited toxicity when intraperitoneally administered. Thus, based on the findings of this study, continued use of the plants extracts and following proper monitoring and evaluation protocol in management of diabetes mellitus is recommended. However, caution should be observed in intraperitoneal administration of some of the extracts. Further isolation and structural characterization of the active constituents of phytochemicals of the plants and ellucidation of the actual mode of action is recommended. Translational clinical reseach is equally recommended on the background of the data obtained in this study to facilitate advances and the integration of the studied alternative botanical therapies for treating diabetes into modern medicine.enAntidiabetic PropertiesSafetyAqueous ExtractsTriticum Aestivum,Hordeum VulgareUrtica MassaicaCynanchum ViminaleRat ModelThesis