Thearubigins protect against acetaminophen-induced hepatic and renal injury in mice: biochemical, histopathological, immunohistochemical, and flow cytometry study.

CONTEXT: Acetaminophen toxicity is used as a model for studying chemical toxicity. N-acetylcysteine (NAC) is used for the treatment of hepatotoxicity; however, there is no specific therapy for nephrotoxicity. OBJECTIVE: This study was designed to investigate the potential protective effect of black tea extract (BTE) and its main phenolic pigment, thearubigins (TRs), against acetaminophen (APAP)-induced hepatic and renal injury in mice. MATERIALS AND METHODS: Besides control groups, six groups (n = 8) were given intraperitoneally APAP (300 mg/kg) and then after 1.5 hours were treated intraperitoneally as follows: NAC (318 mg/kg), BTE (3%, 4.5%), and TRs (50, 60, and 70 mg/kg). Six hours post-APAP injection, blood was collected for biochemical measurements. Later, liver and kidneys were removed for histopathological, immunohistochemical, and flow cytometry studies. RESULTS: APAP increased alanine aminotransferase and malondialdehyde and decreased glutathione levels in blood. Treatments significantly reversed these changes mostly with NAC and TRs70. TRs showed dose-dependent significant differences. The APAP-induced central lobular hepatic necrosis and increased TUNEL positivity were mild with co-administration of NAC and TRs (60, 70) while moderate with co-administration of BTE (3, 4.5) and TRs50. The APAP-increased serum creatinine level was significantly reversed by treatments (mostly TRs60, 70). The APAP-induced renal tubular epithelial degeneration and necrosis were mild with co-administration of TRs (60, 70) while moderate with co-administration of NAC, BTE (3, 4.5), and TRs50. The APAP-accumulated apoptotic cells in sub-G1 phase were significantly decreased by treatments, mostly by NAC and TRs70 in the liver and TRs (60, 70) in kidneys. CONCLUSION: Thearubigins protected against acetaminophen-induced hepatotoxicity and nephrotoxicity in mice possibly through their antioxidant activity.

The influence of smoking on semen quality, seminal microelements and Ca2+-ATPase activity among infertile and fertile men.

OBJECTIVE: Tobacco smoking is now increasing rapidly throughout the developing world and is one of the biggest threats to current and future world health. Several studies have addressed the role of cigarette smoking on semen quality, but the exact mechanisms remain inconclusive. In order to evaluate the detrimental effects of smoking on semen quality among Saudi subjects, the levels of different seminal parameters in smokers were compared to non-smokers. PATIENTS AND METHODS: A total of 159 semen samples (61 smokers and 98 non-smokers) from men attending an infertility clinic for routine infertility workup were sub-grouped into fertile or infertile and were compared based on standard semen analysis (according to WHO guidelines), content of metals (magnesium, zinc and cadmium) and plasma membrane Ca(2+)-ATPase activity of sperms. RESULTS: Cadmium concentration was found significantly higher in smokers than in non-smokers either in fertile or infertile group (2.9+/-0.4 vs 1.4+/-0.7; 2.9+/-0.5 vs 1.3+/-0.7 microg L(-1); respectively). Together with this increase in seminal Cd a significant decrease in Ca(2+)-ATPase activity (21.5+/-2.8 vs 33.71+/-1.2; 20.7+/-1.5 vs 35.07+/-2.9 mmol min(-1) mg(-1) protein, p<0.05), decrease in seminal zinc (109.8+/-8.1 vs 189.7+/-9.9 mg L(-1), p<0.01) and decrease in sperm motility (41.9%+/-2.9 vs 46.01%+/-2.5; 9.8%+/-2.4 vs 15.3%+/-2.7, p<0.05) were found. CONCLUSION: Our data demonstrate that cigarette smoking affects both Ca(2+)-ATPase activity and motility of the spermatozoa. These effects may be attributed to increased seminal cadmium and reduced zinc concentrations.

Role of concurrent S. mansoni infection in H. pylori-associated gastritis: a flow cytometric DNA-analysis and oxyradicals correlations.

BACKGROUND/AIM: Helicobacter pylori infection is associated with the development of atrophic gastritis and increased gastric epithelial proliferation that is important in developing gastric carcinoma. Some countries with a high prevalence of H. pylori infection have high gastric cancer rates, whereas in others these rates are low. Several theories have been advanced to explain this phenomenon. One of these explanations is that the concurrent parasitic infection that is common in the African population might alter the immune response to H. pylori infection and reduce the incidence of atrophic gastritis. The aim of the present study was to assess whether concurrent Schistosoma mansoni infection with H. pylori has an effect on gastric mucosal injury in view of cell proliferation, apoptosis, pathological changes, nitric oxide (NO), oxyradicals and antioxidant capacity status. PATIENTS/METHODS: Between April 2001 and March 2002, 73 patients were subjected to upper gastrointestinal endoscopy for dyspepsia and liver cirrhosis in the National Liver Institute, Menoufiya University. Biopsies were obtained from any lesion as well as from apparently healthy mucosa. Specimens were preserved in RNA later solution, and then kept at -80 degrees C until utilized for estimation of DNA-flow cytometric assay, reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), NO and lipid peroxidation (LPO) product--malondialdehyde (MDA). Diagnosis of bilharziasis was done by stool analysis, or by sigmoidoscopy and rectal snip. RESULTS: Of the 73 patients, 48 were H. pylori-positive, 34 of them were positive and 14 were negative for S. mansoni. Of the 25 H. pylori-negative cases, 18 were positive and 7 were negative for S. mansoni. Concurrent infection with S. mansoni occurred in 34 patients and they had reduced DNA S-phase (7.57 +/- 4.99 vs. 14.5 +/- 3.11, P = 0.001), reduced proliferation activity (9.95 +/- 3.95 vs. 16.78, P < 0.004) and reduced apoptosis (21.83 +/- 11.64 vs. 26.0 +/- 8.31, P > 0.05) compared with H. pylori infected patients alone. CONCLUSIONS: The results demonstrate that concurrent helminthes infection may modify the inflammatory response to gastric H. pylori infection manifested by the reduction of oxyradical-induced DNA-damage, apoptosis and cellular proliferation activity, and the increase in antioxidant production. Concurrent S. mansoni infection may have a protective effect against the possible progression of H. pylori-induced gastritis towards gastric carcinoma.

Does cholecystectomy affect antral mucosa? Endoscopic, histopathologic and DNA flow cytometric study.

BACKGROUND/AIMS: Although cholecystectomy is still the "gold standard" for treatment of gallstones, this operation may be followed by gastric disorders. The aim of this study is to detect the effects of cholecystectomy on gastric antral mucosa. METHODOLOGY: This prospective study has been carried out on 46 patients (20 M & 26 F) with mean age 41.7 +/- 0.2 years for whom simple cholecystectomy for gallstones was decided. Prior to the operation and 1 year after, patients were subjected to the following: clinical assessment, upper gastrointestinal endoscopy, histopathology of antral mucosa, detection of H. pylori and DNA flow cytometry. RESULTS: There was an increase in the number of patients presenting suggestive symptoms of reflux gastritis: patients experiencing epigastric pain increased from 8 (17.4%) to 11 (23.39%) patients, nausea increased from 6 (13%) to 12 (26.1%) patients and bilious vomiting increased from 3 (6.5%) to 11 (23.9%) patients. Mild antral gastritis increased from 20 (43.5%) to 27 (58.7%) patients. Antral gastritis and antral erosions were detected only after the operation in 8 (17.4%) and 2 (4.3%) patients, respectively. The incidence of active chronic superficial gastritis decreased from 23 (50%) to 13 (28.2%) patients while the inactive form increased from 15 (32.6%) to 23 (50%) patients. Chronic atrophic gastritis, intestinal metaplasia and dysplasia were only detected postoperatively in 2 (4.3%) patients each. There was a decrease in the incidence of H. pylori infection from 32 (69.6) to 19 (41.3%) patients. DNA aneuploid pattern increased from 1 (2.2%) to 4 (8.7%) patients and there was a significant increase of DNA index from 1.01 (+/- 0.03) to 1.03 (+/- 0.05) (P < 0.005). CONCLUSIONS: Changes in clinical, endoscopic and histopathologic findings suggest that cholecystectomy may affect gastric antral mucosa due to duodenogastric reflux. Flow cytometry may be used as an objective method for detection and evaluation of postcholecystectomy reflux gastritis.

Cellular proliferation and ploidy of the gastric mucosa: the role of Helicobacter pylori.

BACKGROUND/AIMS: Recently, H. pylori has been recognized as a risk factor for gastric adenocarcinoma. As such, we have analyzed the DNA content of gastric epithelial cells in an attempt to reveal the role of H. pylori in gastric carcinogenesis. METHODOLOGY: Fifty-three subjects presented with gastric dyspepsia, 39 males and 14 females, with a mean age of 42.15 (+/- 13.16) years. They were referred to the out-patient clinic to undergo endoscopic examination for the first time. Biopsy specimens from the antrum of each subject were subjected to culture for the presence of H. pylori histologic diagnosis, and DNA flow cytometry for the analysis of cellular proliferation and DNA policy. RESULTS: The endoscopic diagnoses were normal appearance (12), Gastric ulcer (12), duodenal ulcer (29). Thirty-eight (72%) subjects were positive, and 15 (28%) subjects were negative for H. pylori. Abnormal DNA-content (aneuploidy) was found in specimens from the antrums of 3 patients, 2 patients with duodenal ulcers (DU, and one with a gastric ulcer (GU). The cellular proliferation detected by flow cytometry in the form of proliferative index (PI; percentage of cells in the DNA S and G2M phases) was 27.88 (+/- 12.48) and 14.17 (+/-2.94) in the antrums of those positive and negative for H. pylori, respectively. A very significant increase in the PI (p < 0.005) was found between subjects positive and negative for H. pylori. Patients with DU and H pylori infection had the highest PI, and the PI was significantly higher than in patients with DU, but without infection. Regarding histology, there was a significant increase in the PI in the presence of H. pylori infection in either CAG or dysplasia groups as compared to cases without infection in the same groups. CONCLUSION: These results show that H. pylori infection is associated with changes in the DNA-content and cellular proliferative activity, suggesting that H. pylori may be implicated in gastric carcinogenesis. Also, the significant increase in the PI along the progression of severity of the disease suggests that measuring this parameter might allow more accurate monitoring of patients, so that a targeted therapeutic protocol may be defined.

Apoptosis in chronic gastritis: evaluation of the gastric mucosa by DNA flow cytometry and the expression of the high molecular weight cytokeratin.

BACKGROUND/AIMS: A series of premalignant lesions, including chronic gastritis (CG), intestinal metaplasia (IM) and dysplasia are associated with gastric carcinogenesis. The present study aimed to define these precancerous gastric lesions further by the study of the cellular DNA using flow cytometry, and the expression of the high molecular weight (68 KDa) Cytokeratin "CK1" proposed as a marker for epithelial cells dying by apoptosis. MATERIAL AND METHODS: Multiple antral biopsies from each of 92 cases with gastric dyspepsia were subjected for DNA content analysis using flow cytometry, and immunostaining using anti-CK1 monoclonal antibody. RESULTS: Chronic gastritis (CG) was present in 85 (92.4%) of cases, 14/85 (16.5%) cases showed chronic superficial gastritis (CSG), and 71/85 (83.5%) cases were chronic atrophic gastritis (CAG). Sixty two of the 85 (74.7%) cases with CG revealed variable degrees of activities. A hypodiploid "Sub-G1" peak was detected in 35 of 85 cases with CG. This peak was significantly higher in active chronic gastritis (ACG) than in the inactive (ICG) cases (p < 0.005). Proliferative activity of cases with CG was higher than in normal cases (p < 0.05) and in cases with ACG than in ICG (p < 0.05). Abnormal DNA-content (aneuploidy) was present in 16 (18.8%) of the 85 cases with CG. The presence of gastric epithelial cells with morphological changes typical of apoptosis in cases showing hypodiploid "Sub-G1" peak, high proliferation, and DNA-aneuploidy, suggests that these cells may be apoptotic bodies. Mild degree of apoptosis was present in some cases (57%) with histologically normal mucosa, while dense apoptotic bodies occurred in 87% of cases with chronic gastritis. These apoptotic bodies were constantly expressing CK1, except those in normal mucosa, suggesting that CK1 can be used as a marker for dying epithelial cells by apoptosis. CK1 was detected in 16 (100%) aneuploid cases which also showed apoptosis. CONCLUSION: The presence of apoptotic bodies in cases with chronic gastritis especially in those showing DNA-aneuploidy, may accounts for the deletion of cells with altered DNA.

Correlation between endoscopy, histopathology, and DNA flow cytometry in patients with gastric dyspepsia.

BACKGROUND/AIMS: Gastric cancer has a poor prognosis, this is partly due to the advanced stage in which the tumor is diagnosed. The objective of this study is to elucidate the clinical significance of DNA flow cytometry and study its impact on monitoring the progression of gastric precancerous lesions in patients with gastric dyspepsia, and to correlate between endoscopic and histopathological findings with results of DNA flow cytometry. MATERIAL AND METHODS: A total of 92 cases underwent upper gastrointestinal endoscopy, 69 males with mean age 44.0 years and 23 females with mean age 38.7 years. Based on the endoscopic appearance, patients under study were classified into: 15 cases with endoscopic normal mucosa (EN), 26 cases with endoscopic gastritis (EG), 43 cases with duodenal ulcer (DU), and 8 cases with gastric ulcer (GU). Two antral biopsies were taken for histopathology and DNA flow cytometry. RESULTS: Chronic gastritis (CG) was present in 12 (80%) of EN cases. In DU patients, CG was present in 42 (97.7%) of cases, and it was associated with intestinal metaplasia (IM) in 11 (25.6%), and with dysplasia in 9 (20.9%) of these cases. While in GU patients, CG was present in all cases. Two (13.3%) of endoscopic normal cases revealed DNA aneuploidy in specimens with CG. The incidence of aneuploidy increases as the endoscopic findings changes from EG (15.4%), DU (16.3%) to GU (37.5%), and as the histopathological changes progresses from chronic atrophic gastritis (CAG) (18.2%), IM (21.7%) to dysplasia (33.3%). CONCLUSION: DNA aneuploidy is a useful marker for recognizing the presence of abnormal cells in epithelial lesions of the stomach, and for monitoring the progression of gastric lesions. Patients with gastric dyspepsia should not only be subjected to endoscopy but also to biopsy and DNA flow cytometry to allow the early detection of malignant transformations in gastric precancerous lesions.