Histone deacetylases and acute kidney injury / 生理学报

Histone acetylation is one of the epigenetic modifications. Histone acetylation, which is catalyzed by histone acetyltransferases and negatively regulated by histone deacetylases, plays an important role in a variety of cellular physiological and pathophysiological processes. Recent studies have shown that histone deacetylases are involved in a variety of pathophysiological responses to acute kidney injury, such as apoptosis, dedifferentiation, proliferation and regeneration. This article reviews the role and underlying mechanism of histone deacetylases in acute kidney injury induced by ischemia reperfusion, nephrotoxicants, sepsis and rhabdomyolysis.

Histone Acetylation Level and Histone Acetyltransferase/Deacetylase Activity in Ejaculated Sperm from Normozoospermic Men

PURPOSE: The aim of this work was to evaluate nuclear histone acetylation level and total histone acetyltransferase (HAT) and deacetylase (HDAC) activity in ejaculated sperm and their relevance to conventional sperm parameters. MATERIALS AND METHODS: Thirty-three normozoospermic men were included in this study. Semen samples were processed by swim-up and then immunostained by six acetylation antibodies (H3K9ac, H3K14ac, H4K5ac, H4K8ac, H4K12ac, and H4K16ac). Our preliminary study verified the expression of HAT/HDAC1 in mature human sperm. From vitrified-warmed sperm samples, total HAT/HDAC activity was measured by commercially available kits. Nuclear DNA integrity was also measured by TUNEL assay. RESULTS: The levels of six acetylation marks were not related with conventional sperm parameters including sperm DNA fragmentation index (DFI) as well as HAT/HDAC activity. However, sperm DFI was positively correlated with HAT activity (r=0.038 after adjustment, p<0.02). HAT activity showed a negative relationship with HDAC activity (r=-0.51, p<0.01). Strict morphology was negatively correlated with acetylation enzyme index (=HAT activity/HDAC activity) (r=-0.53, p<0.01). CONCLUSION: Our works demonstrated a significant relationship of acetylation-associated enzyme activity and strict morphology or sperm DFI.

Chromatin regulation in schistosomes and histone modifying enzymes as drug targets

Only one drug is currently available for the treatment and control of schistosomiasis and the increasing risk of selecting strains of schistosome that are resistant to praziquantel means that the development of new drugs is urgent. With this objective we have chosen to target the enzymes modifying histones and in particular the histone acetyltransferases and histone deacetylases (HDAC). Inhibitors of HDACs (HDACi) are under intense study as potential anti-cancer drugs and act via the induction of cell cycle arrest and/or apoptosis. Schistosomes like other parasites can be considered as similar to tumours in that they maintain an intense metabolic activity and rate of cell division that is outside the control of the host. We have shown that HDACi can induce apoptosis and death of schistosomes maintained in culture and have set up a consortium (Schistosome Epigenetics: Targets, Regulation, New Drugs) funded by the European Commission with the aim of developing inhibitors specific for schistosome histone modifying enzymes as novel lead compounds for drug development.

Biphasic modulation of cocaine-induced conditioned place preference through inhibition of histone acetyltransferase and histone deacetylase

To examine the causative relationship between aberrant histone acetylation changes and cocaine-induced reward. Male Sprague-Dawley rats [n=160] were tested by conditioned place preference [CPP] - procedure, to evaluate the effects of inhibitors of histone deacetylase [HDAC] and histone acetyltransferase [HAT] on the conditioned effects of cocaine. Conditioning sessions were conducted twice daily for 2-4 days. For each conditioning session, rats were injected with either HDAC [or HAT] inhibitors or saline in home cages, followed by cocaine [intraperitoneally [ip]] or saline [ip] 30 minutes later, and then immediately confined for 50 minutes in the cue-specific chamber. On the day following the last conditioning session, the rats were tested for place preference for 15 minutes. The present study was carried out at the Department of Pharmacology of Jiaxing University, Jiaxing, Zhejiang, and Pharmacology Research Center of Fudan University, Shanghai, China between October 2007 and January 2009. Our results showed that pretreatment with HDAC inhibitor [sodium butyrate], potentiated cocaine-induced CPP, but did not itself lead to conditioned preferences, or aversions. On the contrary, rats pretreated with curcumin [HAT inhibitor] markedly inhibited cocaine-induced CPP, but did not itself lead to conditioned preferences or aversions. Histone modifications may be an important mechanism that underlies conditioned effects of cocaine. Moreover, HAT may bye a potential therapeutic target for cocaine addiction