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Piotr Zimniak, Ph.D.
Professor

Piotr Zimniak, Ph.D.
PHD
University of Vienna, Austria, 1975

Research Interests
My major research interest is in the physiological and toxicological role of lipid peroxidation. In particular, we are studying the functions of the electrophilic product of lipid peroxidation, 4-hydroxynonenal (4-HNE). The focus of the research is on two phenotypes triggered by excessive 4-HNE levels: curtailed life span and accumulation of fat. We use two model systems. One is the nematode C. elegans, and the other the mouse. The first model permits facile genetic and biochemical manipulations, and makes life span measurements practical. Using this model, we have shown that experimental lowering of tissue 4-HNE levels extends, whereas excessive 4-HNE shortens life. The mouse model provides relevance to mammalian and, by extension, human biology. We generated a knockout mouse with impaired metabolism of 4-HNE and found that 4-HNE triggers obesity, probably via a biochemical rather than an endocrine mechanism. Elevated 4-HNE also causes fat accumulation in C. elegans, indicating an evolutionarily conserved mechanism. Overall, our results show that 4-HNE, which is cyto- and genotoxic at superphysiological concentrations, is also a signaling molecule which modulates a variety of cellular and organismal functions.

E-mail
Zimniakpiotr@uams.edu

Selected Publications
Singh SP, Niemczyk M, Zimniak L, Zimniak P. Fat accumulation in Caenorhabditis elegans triggered by the electrophilic lipid peroxidation product 4-hydroxynonenal (4-HNE). Aging 1: 68-80, 2009.

Zimniak P. Detoxification reactions: relevance to aging. Ageing Res. Rev. 7: 281-300, 2008.

Singh SP, Niemczyk M, Saini D, Awasthi YC, Zimniak L, Zimniak P. Role of the electrophilic lipid peroxidation product 4-hydroxynonenal in the development and maintenance of obesity in mice. Biochemistry 47: 3900-3911, 2008.

Sharma R, Sharma A, Dwivedi S, Zimniak P, Awasthi S, Awasthi YC. 4-Hydroxynonenal self-limits Fas-mediated DISC independent apoptosis by promoting export of Daxx from nucleus to cytosol and its binding to Fas. Biochemistry 47: 143-156, 2008.

Ayyadevara S, Dandapat A, Singh SP, Siegel ER, Shmookler Reis RJ, Zimniak L, Zimniak P. Life span and stress resistance of Caenorhabditis elegans are differentially affected by glutathione transferases metabolizing 4-hydroxynon-2-enal. Mech. Ageing Dev. 128: 169-205, 2007.

View Dr. Zimniak's PubMed publication list.

University of Arkansas for Medical Sciences
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