Histochemical studies the effect of nigella sativa seeds on rat liver enzymes as: tumor Markers

The present investigation was undertaken to discover by enzmological studies whether supplementation of Nigella sativa seeds powder in the food of rats treated with carcinogenic substances dibutylnitrosamine [DBNA] and diethylnitrosamine [DENA] prevents rat liver toxicity. For this purpose, the activity of the enzymes. glucose-6-phosphatase [G6P].5 nucleotidase [5 N], acid phosphatases [AP] and alkaline phosphatases [ALP] were studied histochemically. It has been observed that DBNA and DENA disturb enzyme activity in the liver as DBNA and DENA depressed G6P, 5N and AP and increased ALP in liver cells. Supplementation of Nigella sative seeds powder in the food, prevents or decreases the effect by inhibiting the decrease of the enzymes G6P, 5 N, AP and the increase of the enzyme ALP in liver cells by the carcinogenic substances. In addition, enzyme activities which were studied histochemically are good markers in carcinogenesis studies of antitumor activities

Circadian rhythmometric analysis of hepatic phosphohydrolases with special reference to glucose-6-phosphatase and inorganic pyrophosphatase.

Rhythmometric analysis of a group of phosphohydrolases in mouse liver has been performed along a single 24 hr time scale. The presence of the rhythm was conducted by F test. Statistically significant circadian rhythm was detected in glucose-6-phosphatase (G6Pase) and inorganic pyrophosphatase (InPPase) activity expressed on fresh weight and protein basis. Both G6Pase and InPPase oscillated with a high amplitude of 0.44 U and 1.15 U respectively across the mean value (mesor) of 0.40 +/- 0.42 U and 2.81 +/- 1.14 U per mg protein and with a phase shift of 80 degrees (5.34 hr) among them. On the other hand, alkaline phosphatase (AlPase) did not show any rhythm whereas adenosine triphosphatase (ATPase) showed rhythmic activity on protein basis and oscillated across mesor of 1.84 +/- 0.5 U with an amplitude of 0.52. Acrophase (time for peak activity/mg protein) of G6Pase, InPPase and ATPase was found at 194.2 degrees (13.34 hr), 114.1 degrees (8.0 hr) and at 306.1 degrees (20.4 hr) respectively. AlPase, though did not show significant rhythm, had peak value at 231.8 degrees. Since hepatic G6Pase is a multicomponent and multifunctional enzyme with several overlapping activities (viz. InPPase), coordinated action of G6Pase and InPPase in the regulation of hepatic cell functions has been suggested.

Prednisolone and Glucose-6-phosphatase Activity in Liver Cells

Prednisolone, a cortisol analogue, was given intraperitoneally to rats with 5, 10 or 15 doses of 5 mg. per kg. of body weight per day. Sacrificing the animals 24 hours after the last injection, unfixed frozen sections from small pieces of liver tissue were incubated and stained by a modification from the method of Wachstein and Meisel(1965) for glucose-6-phosphatase (G-6-Pase) activity. Some of the tissue blocks were processed for staining with hematoxylin and eosin for histopathological observation. Glucose-6-phosphatase activity, being represented histochemically by brownish-black deposits, was progressively increased after administrations 5 or 10 times. With 15 doses of prednisolone the general histochemical picture of G-6-Pase activity appeared to be similar to that of the control group, except for a different distribution of hepatocytes possessing strong activity. In prednisolone treated rats, the swollen hepatocytes showed a marked, cytoplasmic vacuolization and nuclear pyknosis, particularly in the periportal and midzonal areas of hepatic lobules. Some discussion of the G-6-Pase corticosteroids are presented in terms of their metabolic effects.