ABSTRACT
Eucalyptus camadulensis leaf is a kind of herbal leaf that is used mainly for the cure of malaria traditionally. In this study, the anti-diabetic effect and biochemical analyses of Eucalyptus camadulensis leaf supplemented diet in streptozotocin-induced diabetic Wistar rats was evaluated.
Eucalyptus camadulensis leaves was collected inside University of Benin behind the male hostel, Ugbowo Campus, Benin City, Edo State, Nigeria. The pulverized leaves of Eucalyptus camadulensis was used in the diet formulation. The methanolic extract of the leaves was made and used for gas chromatography-mass spectrometry (GC-MS). The experiment was divided into four phases of which phase one to three were pilot studies. In the phase four of the experiment eighteen male albino rats were used and grouped into three groups of six rats per group. Group one was normal control, group 2 was diabetes treated and group 3 was diabetes untreated. All the animals were sacrificed after the experimental period of 14 days. The histopathology of the liver, kidney and pancreas was done using heamatoxylin and eosin staining method.
The result showed that Eucalyptus camadulensis leaf-based diet stabilized the blood glucose level which was comparable to the normal control group after 14 days of treatment. It reduced the serum activity levels of AST, ALT as well as the levels of albumin and total bilirubin when compared with diabetes untreated group, but when compared the diabetes treated group with normal control group there are statistically insignificant (p > 0.05). Total protein level of the diabetes treated group is statistically insignificant when compared with the normal control group but when compared with the diabetes untreated group there are statistically significant. Eucalyptus camadulensis leaf-based diet increased the serum activities of SOD, GPx but not catalase which decreased significantly when compared with the diabetes untreated; and when compared with the normal control the serum activities of SOD, GPx and catalase are statistically insignificant (p > 0.05). Furthermore, Eucalyptus camadulensis leaf based diet reduced serum levels of TAG, total cholesterol, LDL and V-LDL significantly (p < 0.05) but not HDL which increased when compared with the diabetes untreated but when compared with the normal control it reduced significantly (p < 0.05) the level of TAG, total cholesterol, LDL, V-LDL and HDL. The result showed Eucalyptus camadulensis leaf based diet on serum level of urea to be significantly (p < 0.05) reduced compared with diabetes untreated group and statistically insignificant (p > 0.05) compared with the normal control. Also, the creatinine level is comparable to the normal control group and significantly (p < 0.05) different compared with the diabetes untreated group. The serum amylase and insulin level showed the amylase level to be reduced and insulin level increased significantly when compared with the controls. The histopathology showed normal hepatocytes, normal acini, resurgence of the islets of Langerhans and a normal kidney after treatment with Eucalyptus camadulensis leaf based diet. The GC-MS showed several compounds with 2-hydroxycarbazole having the highest peak. Carbazole present as the compound is proposed to be the active ingredient that is implicated in the medicinal properties demonstrated leaf. Eucalyptus camadulensis leaf based diet showed a hypolipidemic activity. In conclusion Eucalyptus camadulensis leaf supplemented showed anti-diabetic activity through resurgence of islets of Langerhans, and regeneration of the surviving beta cells which will in turn increase the level of insulin secretion that will then maintain the blood glucose level.
