The study results show that smoking increases the level of free radicals in periodontal tissues, which in turn may be responsible for the destruction seen in periodontal diseases.

D-Galactosamine (800 mg/kg, intraperitoneally) caused significant decrease in the activities of 5'-nucleotidase, glucose-6-phosphatase and cytochrome P450 and increase in activities of gamma-glutamyl transpeptidase, succinate dehydrogenase, acid phosphatase and acid ribonuclease in liver after 24 hr. The levels of RNA, protein and glycogen decreased while total lipids, phospholipids, cholesterol and lipid peroxides increased. It also increased the serum levels of transaminases, alkaline phosphatase and bilirubin while protein concentration decreased significantly. Oral administration of Picroliv (12 mg/kg/day for 7 days), a standardised iridoid glycoside fraction of Picrorhiza kurroa, significantly prevented the biochemical changes in liver and serum of galactosamine-toxicated rats. Kutkoside (12 mg/kg/day for 7 days) also protected against changes in most of the hepatic and serum constituents studied. Another iridoid glycoside from Picroliv, Picroside I, at the same dose level could only prevent toxicant-induced changes in acid phosphatase, phospholipids and lipid peroxides in liver and alkaline phosphatase in serum. Mixture of Picroside I and Kutkoside in the ratio of 1:1.5 at 12 mg/kg dose elicited lesser response than Picroliv.

Thioacetamide (100 mg/kg), when administered to normal rats, caused a significant increase in the activities of 5'-nucleotidase and gamma-glutamyl transpeptidase and a decrease in the activities of glucose 6-phosphatase and succinate dehydrogenase enzymes in the liver. DNA, RNA, and proteins were increased while the cytochrome P450 in the microsomal fraction and the glycogen content in the liver were decreased significantly. Elevations in the activities of GOT, GPT, and alkaline phosphatase and bilirubin content in serum were also observed. Picroliv, a standardised glycoside fraction of Picrorhiza kurroa, in doses of 12.5 and 25 mg/kg prevented most of the biochemical changes induced by thioacetamide in liver and serum. The hepatoprotective activity of Picroliv was comparable with that of silymarin, a known hepatoprotective agent obtained from seeds of Silybum marianum.

No abstract

Single oral administration of paracetamol (2 g/kg body wt) to rats caused significant changes in the activities of y-glutamyl transpeptidase, 5'-nucleotidase, succinate dehydrogenase, glucose-6-phosphatase and cytochrome Pkw and contents of glycogen and cholesterol in liver after 24 and 48 h. Total lipids and lipid peroxides in liver increased both at 24 and 48 h while protein content of liver decreased after 48 h. Levels of transaminases, alkaline phosphatase and bilirubin in serum also increased. The magnitude of these changes was more after 48 h of paracetamol administration. Picroliv, the iridoid glycoside fraction of Picrorhiza kurroa, when given orally to rats (6 and 12 mg/kg body wt for 7 days) caused significant reversal of the paracetamol-induced biochemical changes. The degree of protection at the two doses of picroliv was almost similar.