Cell and Tissue Journal

Abstract Aim: The toxic effects of cadmium exposure are mainly due to the production of oxygen free radicals, reduction of cellular antioxidants and oxidative stress, which can lead to cell component destruction, DNA damage, apoptosis and ultimately tissue damage. In this study, the protective effects of N-acetylcysteine, as a substance with antioxidant properties, in cadmium-exposed Wistar mice were investigated by liver histology and measuring the expression of effective genes in apoptosis and cell proliferation.
Material and Methods: Mice weighing approximately 150-200 g were classified into three treatments including, G1) control treatment, G2) cadmium recipient treatment, and G3) concomitant cadmium and N-acetylcysteine treatment and for four weeks received the desired. Then liver tissue samples were taken for histopathological examination and expression of eif4e and mad1 genes.
Results: The results of this study showed that cadmium exposure resulted in serious damage to rat liver tissue, including central artery hyperemia, increased number of inflammatory cells and inflammation in the liver parenchyma, while the use of N-acetylcysteine significantly reduced the mentioned injuries. Also, the use of N-acetylcysteine resulted in a significant reduction in the expression of eif4e and mad1 genes by 2.14 and 2.27 times, compared with mice that received only cadmium.
Conclusion: The results of this study suggest that N-acetylcysteine as an antioxidant can play an important role in preventing tissue damage due to oxidative stress and preventing the induction of cellular apoptosis.

Abstract

Abstract Aim: In this study gill and mantle histopathological and ultrastructural changes of freshwater bivalve, Anodonta cygnea from Unionidae in exposure to sub-lethal concentrations of copper oxide nanoparticles for 14 days were investigated.
Materials and Methods: Forty numbers of A. cygnea (length: 11.5± 0.9 cm; weight: 84.5±6 g) were collected from Tajan River estuary, Sari, Mazandaran Province and after transferring to the laboratory were divided into two control and treated groups. Treated group were exposed to 25 ppm CuO nanoparticles for 14 days. Gill and mantle tissue sections of control and treated samples were taken in days 4, 9 and 14, and then prepared for light microscopy using hematoxylin and eosin (H & E) staining method. Samples were studied by scanning electron microscopy (SEM) after fixation, drying and preparation.
Results: Light microscopy results showed significant histological alterations in all of studied organs of exposed bivalves compared to the controls. Changes were hyperplasia, hypoplasia, gill filaments shape and dimension changes and also haemolymph channels adema. Also increasing mucous cells number and external epithelium hyperplasia in mantle were observed. SEM analyses showed adverse destruction of gill filaments and blocking water channels in gill specimens, as well as, mantel necrosis and indentation.
Conclusion: according to obtained results, it can be concluded that short time exposure to nanoparticles may lead to noticeable changes evident in histological and ultrastructural internal organs of freshwater bivalve Anodonta cygnea.

Abstract Aim:The aim of this study was to investigate histopathological alterations and their incidence time pattern due to chromium (Cr) exposure during 18 days in gill, digestive gland and foot in freshwater bivalve, Anodonta cygnea.
Material and Methods: 24 bivalve specimens with length range of 12.7-13.3 cm were collected from Semeskandeh region, Sari. They were exposed to 125 µg l^-1 of Cr for 18 days. Bivalves were sampled in days 4, 9 and 18 for obtaining tissue samples of studied organs. Tissue sections of exposed and control group samples were prepared and staining was done using haematoxylin and eosin (H&E) method.
Results: Histology of all of three studied organs of exposed bivalves in comparison with control group showed significant histopathological changes. Hypoplasia and changes in shape and size of gill lamellae, granuloma, hyperplasia and atrophy of haemolymph channels were observed. In digestive gland, atrophy of digestive tubules, loss of digestive and basophilic cells from tubules, and haemocyte aggregation and granuloma in connective tissue were occurred. Hypoplasia of external epithelium, increase of mucus cells, and swelling and tissue rapture in myocyte blocks were observed in foot. Primary signs of histopathological alteration were appeared in fourth day, and in following days appearance of new signs and expansion of affected area was detected in all of investigated organs.
Conclusion: Based on our results, histological changes due to Cr exposure in studied organs in A. cygnea are proposed as appropriate histopathological biomarkers to monitoring Cr levels in aquatic environments and their incidence time pattern can increase fidelity of these indices.