Proteomic Pattern in Overactive Bladder Including Gender Aspects: A Case-control Study

Overactive bladder (OAB), defined as ‘‘urgency with or without urge incontinence, usually with frequency and nocturia’’, has an estimated prevalence of 13% in women (peaking at 20% in patients >70 yr)and 10–26% in men, which might increase up to 48% in women and 60.5% in men if associated with obesity [1,2]. The exact etiology of non-neurogenic OAB remains unknown, although it is generally assumed that neuronal, myogenic, and inflammatory factors play a role in the development of OAB [3,4]. Recent studies have focused on an association between inflammatory processes and OAB, partly driven by a search for OAB-specific biomarkers in urine and/or serum [4]. Inflammatory proteins, such as neuronal growth factor (NGF), brain-derived neurotrophic factor (BDNF), prostaglandins, cytokines, adipokines, monocyte chemoattractant protein-1 (MCP-1), and C-reactive protein, have been investigated in urine and/or serum regarding their OAB specificity, and appear to be expressed at a significantly higher level in comparison to controls. However, these inflammatory proteins are nonspecific and are also elevated in other conditions such as acute cystitis and urinary tract stones. Furthermore, the techniques applied to identify these markers (eg, enzyme-linked immunosorbent assay) require the use of a specific and known antibody for proteins acting as putative biomarkers [5–12]. In screening for unknown proteins that could play a role in processes involved in OAB, proteomic techniques with chromatographic separation and mass spectrometry (LCMS/MS) can detect and analyze all proteins present in a biological sample such as urine. The proteins can be identified with great accuracy and specificity, and can be quantitatively measured simultaneously. This provides a