title: The therapeutic effects of 4-phenylbutyric acid in maintaining proteostasis.
abstract: Recently, there has been an increasing amount of literature published on the effects of 4-phenylbutyric acid (4-PBA) in various biological systems. 4-PBA is currently used clinically to treat urea cycle disorders under the trade name Buphenyl. Recent studies however have explored 4-PBA in the context of a low weight molecular weight chemical chaperone. Its properties as a chemical chaperone prevent misfolded protein aggregation and alleviate endoplasmic reticulum (ER) stress. As the ER is responsible for folding proteins targeted for use in membranes or secreted out of the cell, failure of maintaining adequate ER homeostasis may lead to protein misfolding and subsequent cell and organ pathology. Accumulation of misfolded proteins within the ER activates the unfolded protein response (UPR), a molecular repair response. The activation of the UPR aims to restore ER and cellular proteostasis by regulating the rate of synthesis of newly formed proteins as well as initiating molecular programs aimed to help fold or degrade misfolded proteins. If proteostasis is not restored, the UPR may initiate pro-apoptotic pathways. It is suggested that 4-PBA may help fold proteins in the ER, attenuating the activation of the UPR, and thus potentially alleviating various pathologies. This review discusses the biomedical research exploring the potential therapeutic effects of 4-PBA in various in vitro and in vivo model systems and clinical trials, while also commenting on the possible mechanisms of action.
authors: McMaster University, Department of Medicine, Canada; Firestone Institute for Respiratory Health, The Research Institute of St Joe's Hamilton, Canada.
authors: P S
authors: PS
authors: Kolb
authors: McMaster University, Department of Medicine, Canada; Firestone Institute for Respiratory Health, The Research Institute of St Joe's Hamilton, Canada; McMaster Immunology Research Center, Canada.
authors: E A
authors: EA
authors: Ayaub
authors: McMaster University, Department of Medicine, Canada; Firestone Institute for Respiratory Health, The Research Institute of St Joe's Hamilton, Canada.
authors: W
authors: W
authors: Zhou
authors: McMaster University, Department of Medicine, Canada; Hamilton Centre for Kidney Research, Canada.
authors: V
authors: V
authors: Yum
authors: McMaster University, Department of Medicine, Canada; Hamilton Centre for Kidney Research, Canada.
authors: J G
authors: JG
authors: Dickhout
authors: McMaster University, Department of Medicine, Canada; Firestone Institute for Respiratory Health, The Research Institute of St Joe's Hamilton, Canada; McMaster Immunology Research Center, Canada. Electronic address: askkj@mcmaster.ca.
authors: K
authors: K
authors: Ask
mesh_terms: D000818:Animals; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects; D006706:Homeostasis; D006801:Humans; D010654:Phenylbutyrates / Q000494:pharmacology* / Q000627:therapeutic use; D015398:Signal Transduction; D056811:Unfolded Protein Response / Q000187:drug effects*; D056806:Urea Cycle Disorders, Inborn / Q000188:drug therapy
chemical_list: D010654:Phenylbutyrates; C075773:4-phenylbutyric acid
keywords: 4-PBA; 4-Phenylbutyric acid; ER stress; UPR