Experimental study of histomorphology and oxidative damage in the liver in senescence accelerated mouse (SAMPS) / 中华老年医学杂志

ABSTRACT

Objective To evaluate the feasibility of liver senescence model with senescence accelerated mouse prone 8 (SAMP8), and to explore the possible mechanism of oxidative stress in the process of liver aging in SAMP8. Methods Male SAMP8 mice at the age of 9 months were chosen as research objects, and senescence accelerated mouse resistance 1 (SAMR1) mice were used for normal control. Histopathological changes in the liver of SAMR1 and SAMP8 mice were observed by hematoxylin-eosin (HE), Sudan Ⅳ and Masson staining. Senescence associated β-galactosidase activity was measured by histoehemical staining method, and the activities of superoxide dismutase (SOD), eatalase (CAT), glutathione peroxidase (GSH-Px) and the level of malondialdehyde (MDA) in liver homogenate were examined by chemical colorimetry. Results Compared with SAMR1 group, the liver degenerative changes of SAMP8 mice were observed by microscopy, such as extensive fatty degeneration, focal necrosis of hepatocytes and inflammatory cells infiltration. Meanwhile, senescence associated β-galactosidase-positive cells were significantly increased in SAMP8 group [(78.1±11.0) vs.( 23.9±8.8),t=10.887, P<0.01]. In addition, the activities of SOD, CAT and GSH-Px in liver homogenate were decreased [SOD (214.8 ± 34.8) vs. ( 295.3 ± 29.7), t = 4.975,P<0.01;CAT (23.0±4.0) vs. ( 36.3±8.3),t=4.084,P<0.01;GSH-Px (524.0±74.2) vs. (648. 4±102.8) ,t=2. 776, P<0. 05]and the level of MDA was markedly increased ((2.3±0.2) vs. (1.8±0. 1),t = 6. 329, P<0. 01]. Conclusions SAMP8 mice is a feasible animal model for the study of liver senescence, and oxidative stress may play an important role in the process of liver aging in SAMP8.