Oligomerization of Cu,Zn-Superoxide Dismutase (SOD1) by Docosahexaenoic Acid and Its Hydroperoxides In Vitro: Aggregation Dependence on Fatty Acid Unsaturation and Thiols

Autor(es)

Appolinario, Patricia Postilione ^[1] ; Medinas, Danilo Bilches ^[1] ; Chaves-Filho, Adriano B. ^[1] ; Genaro-Mattos, Thiago C. ^[1] ; Rosa Cussiol, Jose Renato ^[2] ; Soares Netto, Luis Eduardo ^[2] ; Augusto, Ohara ^[1] ; Miyamoto, Sayuri ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim, Dept Bioquim, BR-01498 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Biociencias, Dept Biol, BR-01498 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 10, n. 4 APR 30 2015.
• Citações Web of Science: 6

Resumo

Docosahexaenoic acid (C22:6, n-3, DHA) is a polyunsaturated fatty acid highly enriched in the brain. This fatty acid can be easily oxidized yielding hydroperoxides as primary products. Cu, Zn-Superoxide dismutase (SOD1) aggregation is a common hallmark of Amyotrophic Lateral Sclerosis (ALS) and the molecular mechanisms behind their formation are not completely understood. Here we investigated the effect of DHA and its hydroperoxides (DHAOOH) on human SOD1 oligomerization in vitro. DHA induced the formation of high-molecular-weight (HMW) SOD1 species (>700 kDa). Aggregation was dependent on free thiols and occurred primarily with the protein in its apo-form. SOD1 incubation with DHA was accompanied by changes in protein structure leading to exposure of protein hydrophobic patches and formation of non-amyloid aggregates. Site-directed mutagenesis studies demonstrated that Cys 6 and Cys 111 in wild-type and Cys 6 in ALS-linked G93A mutant are required for aggregation. In contrast, DHAOOH did not induce HMW species formation but promoted abnormal covalent dimerization of apo-SOD1 that was resistant to SDS and thiol reductants. Overall, our data demonstrate that DHA and DHAOOH induce distinct types of apo-SOD1 oligomerization leading to the formation of HMW and low-molecular-weight species, respectively. (AU)

• Processo FAPESP: 10/50891-0 - Ácido docosahexaenóico e colesterol: caracterização e detecção de produtos de oxidação, modificação de proteínas e implicações na esclerose lateral amiotrófica
• Beneficiário: Sayuri Miyamoto
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 09/52702-3 - Avaliação do efeito do ácido docosahexaenóico e de seus hidroperóxidos na oligomerização de SOD1 em um modelo da doença esclerose lateral a miotrófica
• Beneficiário: Patricia Postilione Appolinário
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 13/07937-8 - Redoxoma
• Beneficiário: Ohara Augusto
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs