The Effect of Antioxidant Nutrition against Fenvalerate Toxicity in Rat Liver (Histological and Immunohistochemical Studies).

Aims: Fenvalerate (FEN) is a type II synthetic pyrethroid that has replaced other groups of insecticides due to its improved insecticidal potency. The objective of this study was to investigate the possible role of antioxidant nutrients as a protective agent against alterations of FEN in liver tissue of male albino rats. Study Design: Histological and immunohistochemical studies. Place and Duration of Study: Zoology Department, College of Science, Alexandria University - Egypt, between May 2010 and February 2013. Methodology: Forty animals were divided into four groups of 10 rats each. The first group served as control which received corn oil , second group received a single dose (20mg FEN/kg) 24hours prior to decapitation , third group received (20 mg fish oil (ώ3) /kg/48h) and (4.1 mg selenium (Se) /kg/48h) for 20 days and fourth group received FEN following the supplementation with ώ3 and Se . Results: Histopathological changes in the FEN group illustrated as degeneration and proliferation of hepatocytes forming acinar and pseudoglandular pattern. The previous changes disappeared from FEN+ (ώ3 and Se) group. The histochemical staining of catalase enzyme revealed increased activity in FEN, FEN+ (ώ3 and Se) groups while activity of glutathione reductase enzyme was decreased in compare with control group. Immunohistochemical staining of Bcl-2 oncoprotein increased in the cytoplasm of periportal and centrilobular hepatocytes in FEN and FEN+ (ώ3 and Se) groups, while it decreased in (ώ3 +Se) group. Conclusion: It was suggested that FEN-induced dysregulation of architecture, antioxidant enzymes and expression of Bcl-2 oncoprotein which might be ameliorated by the effect of antioxidant nutrient.

Immunohistochemical Study of Bcl-2 Oncoprotein Expression in Childhood Non-Hodgkin's Lymphoma

PURPOSE: The aim of the present study was to assess the clinicopatholgical significance of Bcl-2 oncoprotein expression in childhood non-Hodgkin's lymphoma (NHL). METHODS: We have assessed 16 cases of childhood NHL during last 6 years from 1990 to 1995. Bcl-2 oncoprotein expression has been semiquantitatively analyzed in paraffin sections from 16 cases of childhood NHL with 39 control cases of adult NHL. The expression of Bcl-2 oncoprotein was correlated with histologic grade, immunophenotype, proliferative activity as measured by immunostain of Ki-67 antigen, clinical stage, and survival rate (event free survival rate, EFS). RESULTS: 1) Bcl-2 oncoprotein expression significantly decreased according to increase of histological grade (P0.05). 5) EFS of patients was significantly correlated with Bcl-2 oncoprotein expression, that is, reduced EFS was demonstrated in the patients with low Bcl-2 oncoprotein expression (P<0.05). CONCLUSIONS: Thus Bcl-2 oncoprotein, as demonstrated immunohistochemically in routinely paraffin embedded tissue, can be restrictively used in prediction of prognosis and grade of childhood NHL, in aggrement with the role of Bcl-2 oncoprotein in blocking of apoptosis and indirect contribution to increase of cellular proliferative activity of NHL.

The Studies of bcl-2 Oncoprotein and Epstein-Barr Virus Expression in Malignant Lymphomas: Immunohistochemical and in situ hybridization analysis on 66 cases

Bcl-2 oncoprotein is being localized to mitochondria and interfering with programmed cell death (apoptosis) independent of promoting cell division in the lymphoid and nonlymphoid cells. The bcl-2 oncoprotein expression has been reported in follicular lymphomas as well as in diffuse non-Hodgkin's lymphoma, leukemia and a variable propotion of Hodgkin's lymphoma cases. Recent evidence suggests that some lymphomas protected from apoptosis is conferred through expression of Epstein-Barr virus(EBV) latent membrane protein which turn to cause upregulation of bcl-2. To define the role of the bcl-2 oncoprotein and EBV in lymphoid malignancy, we tried immunohistochemical studies with anti-bcl-2 antibody and In situ hybridization (ISH) with EBV-encoded small nuclear RNAs(EBER) in the paraffin embedded sections of 46 non-Hodgkin's lymphoma (NHL) cases and 20 Hodgkin's lymphoma (HL) cases. Bcl-2 oncoprotein expression was found in 37 of 46 cases (80%) of NHL with relatively strong cytoplasmic staining, and in 14 of 20 cases (70%) of HL with weak cytoplasmic staining in limited small numbers of RS, Hodgkin and lacunar cells. The widespread presence of bcl-2 oncogene in many different types of both NHL and HL supports that the extended cell survival through overexpression of bcl-2 gene protein may be a growth advantage of neoplastic lymphoid cells. In the ISH analysis for EBV, the presence of EBV was detected in 17 of 20 cases (85%) of HL, compared to 6 of 44 cases(13.6%) of NHL. It appears to be no direct correlation between overexpression of bcl-2 oncoprotein by neoplastic lymphoid cells and the presence of EBV in NHL but it seems to be a definite association between EBV and HL.

Expression Patterns of Bcl-2 and PCNA in Cervical Intraepithelial Neoplasia

Immunohistochemical stains for bcl-2 oncoprotein and PCNA and examination of the mitosis level were perfon-ned in 76 cases of cervical intraepithelial neoplasia (CIN). We studied the expression pattern of bcl-2 protein according to histologic grades and the function of bcl-2 oncogene associated with cellular proliferation by comparing with PCNA expression and the mitosis level. The results were as follows: 1) Of 76 cervical intraepithelial neoplasias, 23 (30.3%) were CIN I, 23 (30.3%) were CIN II, and 30 (39.4%) were CIN III. 2) Of 23 CIN I cases, grade 0 and 1 mitosis level were seen in 20 (87.0%), PCNA in 16 (69.6%), and bcl-2 in 19 (82.6%) cases, respectively, which indicates that CIN I lesions have a low cellular proliferative activity. 3) Of 30 CIN III cases, grade 2 and 3 mitosis level were noted in 28 (93.3%), PCNA in 25 (83.3%) and bcl-2 in 19 (63.3%) cases, respectively, which indicates that CIN III lesions have a high cellular proliferative activity. The results suggest that progressive increase of dysfunctional proliferative activity and abnormal decrease of cell death result in increased number of neoplastic cells according to CIN grade. Also the expression rate of bcl-2, PCNA and mitosis level were significantly different between CIN I and 111, which suggest that they might be good parameters for classifying CIN into low and high grade and for prediction of the biologic behavior of the CIN lesion.