The Nile catfish, CLarias gariepinus was treated with aqueous fenugreek seeds (Trigonella foenum-graecum) suspension (AFSS), either separately or in combination with either glucose or alloxan for 5, 24hr (single dose) and 4days (repeated doses). Serum glucose, total free amino acids (TFAA), total lipids (TL), triglycerides (TR), cholesterol (CHO), total protein (TP), urea, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) as well as glycogen, TFAA, TL, TR contents of liver, white and red muscles were determined. Besides muscle CHO, liver AST, ALT and urea were measured. In addition, histological and ultrastructural changes of the liver were examined after 4 days.
Marked hypoglycemia was induced in fish treated with AFSS, while normoglycemia was detected in fish groups treated with AFSS plus glucose or AFSS plus alloxan. These results were accompanied with an elevation in the level of muscle glycogen. Also, AFSS was found to raise the red and white muscle storage of lipids and triglycerides. The results may also reveal that fenugreek seeds stimulate both muscle glycogenesis and lipogenesis, probably at expense of blood glucose. Normal levels of blood sugar, TL, CHO, ALT and ALP as well as liver TL in the fish treated with AFSS plus alloxan were detected.
Regarding the histological ultrastructural observations, the administration of AFSS plus alloxan induced some changes in the liver cells including necrosis, disruption of rough endoplasmic reticulum (rER) and appearance of vacuoles in cytoplasm. Moreover, there was no change in the liver cells in response to AFSS solely or AFSS plus glucose treatments. The only observation was the enlargement of the liver nuclei in all treated fish groups as compared with control.

The effect of a single i.p dose of glucose (1.67g / kg body wt.) on the blood sugar level was examined to study the glucose tolerance test (GTT) in the Nile fish Clarias gariepinus. This study also dealt with the effect of orally administered aqueous extract of lupine or fenugreek seeds on the improvement of GTT. On the other hand, the ameliorating effects of these legumes on the histological changes as well as on the glycogen content in the kidney of the fish treated with either a single dose of alloxan (300 mg / kg body wt) or repeated injected doses of glucose (RDGI) (1.67g / kg body wt for 4 days) were tested. The GTT curve peaked at approximately 2hr and the induced hyperglycemia continued to more than 24hr suggesting that Clarias gariepinus is glucose intolerant. On the other hand, the data show that lupine seeds extract ameliorating effect on the GTT was more than that of fenugreek. In the kidney, alloxan and glucose administrations induced pathological lesions in the form of hydropic degeneration of some renal tubules cells, conspicuous areas of necrosis as well as great widening of Bowman’s space due to shrinkage of glomerular tufts. In addition, these treatments led to glycogen accumulation in the kidney. The main cause of such effects may be attributed to the prolonged hyperglycemia. All these lesions were restored after the administration of lupine or fenugreek extracts for 4 days. The ameliorating effect of such extracts may be due to their stimulatory effect on the blood glucose clearance.

Fish, Chrysichthys auratus were orally administered doses of garlic (Allium sativum) juice equivalent to 2g /kg b. wt. as a single dose or the same dose every 48h for 5 and 11 days. The fish were dissected 24 after the last dose. Serum glucose, total free amino acids (TFAA), total lipids, triglycerides, cholesterol, total protein, urea, AST, ALT and alkaline phosphatase (ALP) were determined. The levels of glycogen, total lipid, triglycerides and TFAA were measured in both liver and white muscle. Also, the liver and kidney were investigated histopathologically and histochemically. The results showed a hypoglycemia, hypolipidemia, hypocholesterolemia, hypotriglyceridemia and drop in serum TFAA as well as promotion of lipogenesis and glycogenesis in white muscle in response to repeated doses of garlic. Such results may correlate with the elevation of insulin release in the fish following the garlic administration. However, both histological and biochemical studies confirmed the liver glycogen depletion after garlic treatment. besides, histopathological changes in the liver after garlic treatment included vacuolation and hypertrophy and degeneration of some hepatocytes, dilatation and congestion of some blood vessels . The histopathological changes of the kidney in response to garlic administration were vacuolation and rupture of some renal tubules and degeneration of the parietal cells of some Malpighian corpuscles. Moreover, garlic decreased the amount of collagenous fibres in both liver and kidney as well as it reduced carbohydrate content in the kidney. In spite of some cell degeneration in the liver and renal tubules, the serum AST and ALT did not show any significant changes, while serum ALP was decreased. Generally, it could be concluded that garlic showed a high effect on the carbohydrate metabolism in Chrysichthys auratus. Also, garlic may improve the carbohydrate metabolism which probably, leads to lower the dietary protein costs of the fish. The damage effect of garlic on both liver and kidney may be attributed to the relative high dose of garlic used in this work.