Biomedical subjects

M H Moghadasian

Publications and source records attributed to M H Moghadasian.

22 records · Page 2Linked to original sources

PubMed1996

Ethanol-induced gastrointestinal damage. Influence of endogenous antioxidant components and gender.

This study compared the effects of undiluted and 8% ethanol administered orally on gastrointestinal antioxidant components of male and female rats. Eight percent ethanol increased the activities of duodenal glutathione peroxide (29% in males, 14% in females) and superoxide dismutase in female gastric (24%) and male duodenal (15%) mucosa. This dose of ethanol also increased the glutathione content of gastric mucosa (12% in males, 13% in females). Undiluted ethanol decreased glutathione levels in gastric mucosa (22% in males, 11% in females) and increased glutathione peroxide activity in gastric mucosa (14% in males, 9% in females). Undiluted alcohol also produced decreases in the activity of glutathione reductase in stomach (14% in males, 9% in females) and duodenum (16% in males, 12% in females). Undiluted ethanol caused mucosal damage in the body of the stomach in both genders, accompanied by an increase in luminal pH and fluid accumulation in the stomach; these changes were absent in rats given 8% ethanol. The increase in gastrointestinal antioxidant capacity associated with the administration of 8% ethanol may be a factor in the reported cytoprotective effect of lower doses of ethanol.

Animals↗

PubMed1996

Endogenous antioxidant status in neoplastic and adjacent tissues in 1,2-dimethylhydrazine-induced colon cancer in rats: effects of olsalazine.

There is much evidence suggesting a possible role of reactive oxygen-derived substances in the pathogenesis of both ulcerative colitis and colon cancer. The antioxidant effects of 5-aminosalicylic acid (the active moiety of olsalazine) on induction of colon cancer in an experimental model using 1,2-dimethylhydrazine were studied in male Wistar rats. The levels of reduced glutathione were significantly (P < 0.01) decreased (by approximately 50%) in neoplastic tissues of rats receiving 1,2-dimethylhydrazine alone and olsalazine treatment significantly (P < 0.01) reduced the extent of this alteration. Adjacent tissues from rats receiving either carcinogen alone or carcinogen and olsalazine showed comparable levels of glutathione and these were significantly (P < 0.01) lower than corresponding control values and higher than corresponding values from neoplastic tissues. Activity of the glutathione regenerating enzyme glutathione reductase was significantly (P < 0.01) decreased (by approximately 40%) in neoplastic colonic tissue and this alteration was unaffected by olsalazine treatment. Neither carcinogen nor olsalazine treatment caused alterations in activity of glutathione reductase in adjacent tissue as compared with corresponding control values. Activity of the glutathione utilizing enzyme glutathione peroxidase was significantly (P < 0.01) increased (almost doubled) in neoplastic tissue of rats treated with carcinogen alone. Olsalazine treatment significantly (P < 0.01) reduced the elevation in glutathione peroxidase activity in neoplastic tissues of rats treated with the carcinogen. Glutathione peroxidase showed comparable activity in adjacent tissue from rats treated with either carcinogen alone or a combination of carcinogen and olsalazine and these values were significantly (P < 0.01) lower than corresponding control values. Colonic neoplastic tissues from all experimental groups of animals showed a small, but statistically significant (P < 0.05), decrease in superoxide dismutase activity compared with that in corresponding tissues from control animals.

1,2-Dimethylhydrazine↗

PubMed1995

Species-related variations in antioxidant components of gastric and duodenal mucosa.

Enzymatic and non-enzymatic antioxidant profiles of the gastric and duodenal mucosa of rat, rabbit, cat and pig were investigated and found to exhibit significant variations. Rat gastric and duodenal mucosa exhibited the highest levels of basal glutathione of the various tissues examined. The highest activity of glutathione reductase was found in the gastric and duodenal mucosa of rat as compared with that in these tissues from the other species. The gastric mucosa of cat and pig showed similar activities of glutathione peroxidase, which was significantly lower than those in rat or rabbit gastric mucosa. The activity of this antioxidant enzyme was similar in rat, rabbit and pig duodenal mucosa and lower than that in cat duodenal mucosa. Strong correlations were found between activities of the functionally coupled antioxidant enzymes glutathione peroxidase and glutathione reductase in gastric but not in duodenal mucosa. The activity of superoxide dismutase showed negligible regional or species-related variations in activity.

Animals↗

PubMedDate not supplied

Surgical management of dyslipidemia: clinical and experimental evidence.

Coronary artery disease (CAD) is still a major cause of mortality in developed countries, and dyslipidemia is one of its major causes. In an attempt to reduce both mortality and morbidity from CAD, several dietary, pharmacological, and surgical approaches have been used to reduce plasma cholesterol levels. In this brief review, we summarize the evidence for cholesterol-lowering effects and safety of partial ileal bypass (PIB) procedure in both human and animal studies. The results of the Program on the Surgical Control of the Hyperlipidemias (POSCH), which involved a total of 838 subjects with myocardial infarction, are promising. A 5-year follow-up of this study revealed significant reductions of up to 27% in total cholesterol (TC) and up to 42% in low-density lipoprotein (LDL) cholesterol levels along with an increase of up to 8% in high-density lipoprotein (HDL) cholesterol levels as compared to controls. These changes were associated with other benefits such as increased HDL/TC and HDL/LDL ratios, and a significant decrease in apolipoprotein (apo) B100 and increase in apo AI levels. Similar results were also demonstrated by other studies. PIB surgery is one of the most effective methods for reduction of plasma cholesterol levels, particularly in patients with heterozygous familial hypercholesterolemia. This procedure is also applicable to treatment of sitosterolemia, a rare genetic disorder in which the absorption of plant sterols is abnormally high. Although no major complications of this method have been reported, more extensive studies are required to evaluate its long-term effects on renal and hepatic function. Similarly, long-term impact of this procedure on progression/regression of atherosclerotic lesions must be documented. Finally, indications for this procedure should be carefully considered, particularly in view of availability of other treatments of dyslipidemia.

Animals↗