Hepatocyte Apoptosis In The Patients With Chronic Hepatitis B

Objective To investigate the relationship between hepatocyte apoptosis and the level of inducible nitric oxide synthase (iNOS) in hepatic tissue in the patients with chronic hepatitis B (CHB) .Methods we observed 74 cases with CHB and 10 normal controls. In control and patients group, transferase mediated UTP-biotin nick-end labling ( TUNEL) technique was used to detect apoptosis cells and immunohistochemical staining were also performed to investigate the expression of inducible nitric oxide synthase (iNOS) in biopsy samples. The serum level of ALT, HBV-DNA, grading of necroinflammatory activity and staging of fibrosis were also assessed.Result1. The mean age of the 74 CHB patients is 33.1 years old, including 41 males and 33 females. About 44 patients had abnormal serum ALT levels (184.6±114.5 U/L) , and about 30 had normal levels (27.6±8.3 U/L) .We recruited 10 healthy volunteers as control.2. Apoptosis result: We observed TUNEL-positive hepatocytes in all 74 biopsy specimens from patients with chronic hepatitis B, but none or rare in 10 controled liver specimens. Apoptotic bodies were only detected within the Kupffer cells,with strong staining of shrunken nuclear chromatin fragments, and were not calculated because it might overrate the degree of apoptosis. Apoptotic cells and bodies were seen both in the periportal and intralobular areas. but tended to cluster at the vicinity of infiltrating lymphocytes. We use apoptosis index to assessed the tunel-positive cells in liver specimens which was expressed as the ratio of apoptotic hepatocytes to the total cells per high power (×400) in at least five random microscopic felds for each specimen. The mean number of apoptotic index in patients with CHB was 7.60±0.43, which is significantly higher than controls.3. INOS expression: We did not find iNOS expression in 10 controls. About 71.3% patients were observed the expression of iNOS, which was significantly higher than controls. The positive cells were stained yellow, homogen or granula. iNOS was mainly expressed in endochylema, occasionally in nucelus.4. Analysis results A significant correlation was seen between apoptosis index (AI) and necroinflammatory grading (r=0.404, P=0.015) and serum iNOS level(r=0.45, P=0.004) . We did not find significant different of apoptosis index between patients with elevated levels of ALT and the ones with normal. AI of CHB patients did not correlate with fibrosis stages, serum alanine aminotransferase levels and HBV DNA loads.Conclusion The NO levels in patients with CHB may effect the hepatic apoptosis. Apototic hepatocyte may be involved in the liver injury of patients with CHB, but did not correlate with serum levels of ALT.