[Effects of sodium aescinate on the apoptosis-related genes in lung injury induced by intestinal ischemia reperfusion in rats].

OBJECTIVE: To investigate the relationship between apoptosis-related genes and lung injury induced by intestinal ischemia reperfusion and to explore the effects and its possible mechanism of sodium aescinate. METHODS: Rat model of intestinal I/R injury was established with clamping of the superior mesenteric artery for 60 min and then clamping was relieved for 60 min. Twenty-four SD rats were randomly divided into three groups with eight rats in each: sham group, intestinal ischemia/reperfusion group (I/R group) and sodium aescinate group (SA + I/R group). Lung wet/dry weight ratio, lung coefficient and Superoxide dismutase (SOD), malondialdehyde (MDA) in plasma and lung tissue were measured, as well as the expression levels of Bcl-2 and Bax proteins in lung tissue were examined using immunohistochemical method. RESULTS: Compared with sham group, lung wet/dry weight ratio, lung coefficient and MDA in plasma and lung tissue were significantly increased, and while the activity of SOD in plasma and lung tissue were decreased significantly in I/R group. At the same time, the protein expression level of Bcl-2 and Bax were significantly increased. But Bax protein expression was much greater than that of Bcl-2, the ratio of Bcl-2 to Bax was decreased significantly in I/R group than that in sham group. Compared with I/R group, lung wet/dry weight ratio, lung coefficient and MDA in plasma and lung tissue were significantly decreased, and while the activity of SOD in serum and lung tissue were significantly increased in SA + I/R group. At the same time, Bax protein expression was significantly decreased, both Bcl-2 protein expression and the ratio of Bcl-2 to Bax were significantly increased in SA + I/R group than that in I/R group. CONCLUSION: Lung injury induced by intestinal ischemia reperfusion is correlated with abnormal expression levels of Bcl-2 and Bax protein which is caused by oxidative injury. Sodium aescinate can protect the lung injury induced by intestinal ischemia/reperfusion (I/R), which may be mediated by inhibiting lipid peroxidation, upregulating Bcl-2 gene protein expression, improving the ratio of Bcl-2/ Bax to inhibit lung apoptosis.

[The protective effects of ischemia preconditioning on the lung injury following with limbs ischemia/reperfusion].

OBJECTIVE: To explore the protective effects of ischemic preconditioning (IPC) on the lung injury following with limbs ischemia /reperfusion (LI/R). METHODS: The models of LI/R injury were constructed in rabbits. The blood from right external jugular vein and left common carotid artery, into and out-flowing pulmonary blood (IPB, OPB) respectively. Superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO) in IPB and OPB and lung tissues were measured, as well as total nitric oxide synthase (tNOS) and inducible nitric oxide synthase (iNOS) in lung tissues were detected in different groups. The effects of IPC on the lung injury were observed. RESULTS: Compared with sham and before ischemic, the activity of SOD decreased and the content of MDA and NO increased after 4 h ischemia followed by 4 h reperfusion in IPB, OPB and lung tissues. The activity of tNOS and iNOS in lung tissues increased remarkably as well, there was statistical significance (P < 0.05, P < 0.01). SOD increased and MDA, NO, tNOS, iNOS decreased significantly by IPC before ischemia/reperfusion. The correlation analysis indicated that MDA was negatively correlated with SOD and was positively correlated with MDA, NO, iNOS (P < 0.01). CONCLUSION: Oxygen free radicals metabolic confusion of lung occurred in the course of LI/R, IPC could strengthen the resistance of peroxidation in lung and had protective effects on the lung injury following with LI/R.

[Difference in seedlings ammonium assimilation of wheat cultivars with different drought resistance under osmotic stress].

Taking wheat cultivars drought-resistant Luohan-6 and drought-sensitive Zhoumai-18 as test objects, their seedlings ammonium assimilation enzyme activities and related parameters were determined under osmotic stress. The plant biomass had an obvious decrease under osmotic stress, with a larger decrement for Zhoumai-18 than Luohan-6. Osmotic stress increased the plant ammonium content, especially for Zhoumai-18. The glutamine synthetase (GS) activity varied with wheat cultivars. For Luohan-6, the GS activity increased significantly under low osmotic stress but decreased under high osmotic stress; while for Zhoumai-18, the GS activity decreased with increasing osmotic stress. The NADH-dependent glutamate dehydrogenase (NADH-GDH) increased with increasing osmotic stress, with a marked increment under low osmotic stress for Zhoumai-18, and under high osmotic stress for Luohan-6. The NAD(+)-dependent glutamate dehydrogenase (NAD(+)-GDH) and NADP-dependent isocitrate dehydrogenase (NADP-ICDH) activities also increased with increasing osmotic stress, with a greater increment of NAD(+)-GDH activity for Zhoumai-18, and of NADP-ICDH activity for Luohan-6. It was suggested that the increased drought resistance of wheat plants could be related to the increased ammonium assimilation resulted from the enhanced GS and NADH-GDH activities under low and high osmotic stress, respectively.

[The protective effects of ischemic preconditioning on the kidney injury following with ischemia/reperfusion of limbs and the possible mechanisms].

AIM: To explore the protective effects of ischemic preconditioning on the kidney injury following with ischemia/reperfusion (I/R) of limbs. METHODS: The models of I/R injury of limbs were constructed in rabbits. The blood from right external jugular vein, renal artery and renal vein represent the peripheral blood, into and out-flowing kidney blood (IKB, OKB) respectively. Superoxide dismutase (SOD), malondialdehyde (MDA), blood uria nitrogen (BUN) in peripheral blood and SOD, MDA, nitric oxide (NO) in IKB and OKB were measured, as well as SOD, MDA, induced nitric oxide synthase (iNOS) in kidney were detected in different groups. The effects of ischemic preconditioning (IPC) on the kidney injury were observed. RESULTS: Compared with control group, the activity of SOD in peripheral blood, IKB, OKB and kidney decreased, and the content of MDA increased after 4 h ischemia followed by 4 h reperfusion. The content of BUN in peripheral blood, NO in IKB, OKB and iNOS in kidney increased remarkably as well. SOD increased and MDA, NO, BUN, iNOS decreased significantly by ischemic preconditioning (IPC) before ischemia/reperfusion. The correlation analysis indicated that MDA was negatively correlated with SOD and positively correlated with NO, BUN. CONCLUSION: Oxygen free radicals metabolic confusion of kidney occurred in the course of I/R of limbs, IPC could strengthen the resistance of peroxidation in kidney and had protective effects on the kidney injury following with ischemia/reperfusion (I/ R) of limbs