Erectile tissue molecular alterations with aging-differential activation of the p42/44 MAP Kinase pathway

• Tipo: Artigo em Revista Científica Internacional
• Data: 2011

Autores

castela, a (Autor) Outra; soares, r (Autor) FMUP; rocha, f (Autor) Outra; vendeira, p (Autor) Outra; virag, r (Autor) Outra; costa, c (Autor) Outra

Revista

Título: Age

Vol. 33

Páginas: 119-130

ISSN: 0161-9152

Editora: Kluwer Academic Publishers

Indexação

ISI Web of Knowledge - 9 Citações

Scopus - 9 Citações

Outras Informações

ID Authenticus: P-002-QZF

DOI: 10.1007/s11357-010-9167-3

Abstract (EN): Erectile dysfunction (ED) is a common problem in aged men; however, the molecular events involved in aging ED remain unclear. To better characterize the effects of aging in the penis, we evaluated cavernosal tissue remodeling capability and the downstream activation of the intracellular signaling mediator mitogen-activated protein p42/44 kinase (p42/44 MAPK). We used male Wistar rats, which were divided in groups of 2, 6, 12, 18, and 24 months old. Penile tissues were harvested and processed for protein isolation and immunohistochemical analysis. Cavernosal viability was assessed by TUNEL assay, and proliferation was analyzed by immunohistochemical detection of proliferating cell nuclear antigen (PCNA). Immunolocalization of the activated form of p42/44 MAPK was evaluated by immunofluorescence, and changes in its phosphorylation status were quantified by western blotting. p42/44 phosphorylation profile was also assessed in situ in human young and elderly cavernosal samples. With the advancement of age, experimental cavernosal tissue remodeling was affected by an age-dependent unbalance between the rate of apoptosis and proliferation, in all erectile components. Moreover, this turnover alteration was accompanied by significant modifications in the activation profile of the downstream effector p42/44 MAPK. In the youngest corporeal samples, p42/44 was mostly activated at perivascular sites, potentially mediating cell survival/proliferation. However, in elderly experimental erectile tissue, p42/44 phosphorylation shifted to trabecular fibroblasts, indicating a potential role in extracellular matrix (ECM) production. More importantly, the same differential pattern of p42/44 activation was observed in human young and aged cavernosal fragments, suggesting a distinct function of this protein with aging. We provided evidence for the first time that with the advancement of age, there is a differential activation of p42/44 MAPK in cavernosal tissue, which may promote ECM expansion and fibrosis, therefore compromising erectile function in the elderly.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 12