title: Aldo-keto reductases and bioactivation/detoxication.
abstract: Aldo-keto reductases (AKRs) are soluble NAD(P)(H) oxidoreductases that primarily reduce aldehydes and ketones to primary and secondary alcohols, respectively. The ten known human AKR enzymes can turnover a vast range of substrates, including drugs, carcinogens, and reactive aldehydes. They play central roles in the metabolism of these agents, and this can lead to either their bioactivation or detoxication. AKRs are Phase I drug metabolizing enzymes for a variety of carbonyl-containing drugs and are implicated in cancer chemotherapeutic drug resistance. They are involved in tobacco-carcinogenesis because they activate polycyclic aromatic trans-dihydrodiols to yield reactive and redox active o-quinones, but they also catalyze the detoxication of nicotine derived nitrosamino ketones. They also detoxify reactive aldehydes formed from exogenous toxicants, e.g., aflatoxin, endogenous toxicants, and those formed from the breakdown of lipid peroxides. AKRs are stress-regulated genes and play a central role in the cellular response to osmotic, electrophilic, and oxidative stress.
authors.affiliation: Department of Pharmacology, Center of Excellence in Environmental Toxicology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Jin
authors.forename: Trevor M
authors.initials: TM
authors.lastname: Penning
mesh_terms: D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D000449:Aldehyde Reductase; D000447:Aldehydes / Q000378:metabolism / Q000633:toxicity; D000074408:Aldo-Keto Reductases; D000903:Antibiotics, Antineoplastic / Q000378:metabolism; D002273:Carcinogens / Q000378:metabolism; D002491:Central Nervous System Agents / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006728:Hormones / Q000378:metabolism; D006801:Humans; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism / Q000633:toxicity
chemical_list: D000447:Aldehydes; D000903:Antibiotics, Antineoplastic; D002273:Carcinogens; D002491:Central Nervous System Agents; D006728:Hormones; D011084:Polycyclic Aromatic Hydrocarbons; D000429:Alcohol Oxidoreductases; D000074408:Aldo-Keto Reductases; D000449:Aldehyde Reductase