Nova1 mediates resistance of rat pheochromocytoma cells to hypoxia-induced apoptosis via the Bax/Bcl-2/caspase-3 pathway.

Neuro-oncological ventral antigen 1 (Nova1) is a well known brain-specific splicing factor. Several studies have identified Nova1 as a regulatory protein at the top of a hierarchical network. However, the function of Nova1 during hypoxia remains poorly understood. This study aimed to investigate the protective effect of Nova1 against cell hypoxia and to further explore the Bax/Bcl-2/caspase-3 pathway as a potential mechanism. During hypoxia, the survival rate of pheochromocytoma PC12 cells was gradually decreased and the apoptosis rate was gradually increased, peaking at 48 h of hypoxia. At 48 h after transfection of PC12 cells with pCMV-Myc-Nova1, the expression of Nova1 was significantly increased, with wide distribution in the cytoplasm and nucleus. Moreover, the survival rate was significantly increased and the apoptosis rate was significantly decreased. Additionally, the mRNA and protein expression levels of Bax and caspase-3 were significantly increased in the pCMV-Myc group and significantly decreased in the pCMV­Myc-Nova1 group, whereas that of Bcl-2 was significantly decreased in the pCMV-Myc group and significantly increased in the pCMV-Myc-Nova1 group. This study indicated that Nova1 could be linked to resistance to the hypoxia-induced apoptosis of PC12 cells via the Bax/Bcl-2/caspase-3 pathway, and this finding may be of significance for exploring novel mechanisms of hypoxia and the treatment of hypoxia-associated diseases.

[Impact of Precipitation on Fenghe River Water and Aquatic Microorganisms].

In view of that the Fenghe River water pollution has become more and more serious, nitrogen and organic matter pollution were put forward as the important study targets. Community structure of the microorganisms could reflect the water pollution condition to a certain degree. By investigating the correlation between the water condition changes and the microbial community variation, it make possible to look upon river pollution from different perspectives. By the use of Illumina high-throughout sequencing, we found that the dominant genera were Acinetobacter, Comamonadaceae, Pseudomonas and Escherichia in Fenghe River aquatic environment. Flavobacterium and Enterobacteriaceae which are known as bacteria closely related to human activities, were found to account for larger percentages in the wet season than in the dry season, thus showing that the river was more influenced by anthropogenic activities in the wet season. The water quality was better in the wet season, while the microbial community structure was more stable and the diversity condition was better in the dry season. From the aspect of chemical pollution and microbe, this research helps to carry out planning for protection of drinking water sources and improvement of water environmental condition.

Beneficial and side effects of arginine vasopressin and terlipressin for septic shock.

Arginine vasopressin (AVP) and its analog, terlipressin (TP), were all demonstrated beneficial for septic shock. What advantages and disadvantages that AVP and TP have for septic shock as well as the mechanism, however, are not completely known. With cecal ligation and puncture-induced septic shock rats and lipopolysaccharide-induced septic shock rabbits, we systematically compared the beneficial and side effects of AVP and TP, in septic shock and the sex difference, and investigated their relationship to Rho kinase and calcium sensitivity. The results indicated that low dose of TP (2.6 µg/kg/h) in combination with norepinephrine (NE) improving vascular reactivity and animal survival were superior to a small dose of AVP (0.03 U/kg/h) in septic shock rats and rabbits. This improving effect of AVP and TP on vascular reactivity was closely related to the activation of Rho-kinase and Rho-kinase-mediating vascular calcium sensitization. A small dose of TP did not result in hyponatremia, did not increase blood bilirubin and decrease platelet count, whereas AVP did. Animal survival and vascular reactivity in female rats after TP or AVP administration were slightly better than male rats, while there were no significant differences. It was suggested that a small dose of TP has better beneficial effect and less side effects on septic shock than AVP. AVP and TP improving vascular reactivity is closely related to Rho-kinase activation and calcium sensitivity improvement. TP or plus NE may be more appropriate for early emergency care for severe septic shock than AVP.