The long term goal of our research is to use a naturally occurring feline model to gain a sufficient understanding of the causes of interstitial cystitis (IC), an idiopathic chronic pain syndrome affecting humans and domestic cats, to permit development of effective therapies. Converging lines of research have found that adverse experience during the prenatal and early postnatal periods can result in a """"""""re-programming"""""""" of the stress response system that is hypothesized to predispose susceptible individuals to a variety of diseases in later life. Such events have occurred in many patients with disorders co-morbid with IC. Moreover, an adrenocortical abnormality in cats with IC likely results from early adverse experience, making these cats an important naturally occurring model of IC. The hypothesis to be tested in this proposal is that adverse experience leads to alterations in DNA methylation, an epigenetic change that results in altered gene expression and increases susceptibility for the development of the bladder and neuroendocrine abnormalities observed in cats with FIC and humans with IC. The specific objectives of this proposal are to: 1) investigate the differential expression of genes in urothelium and adrenal cortex between normal cats and cats with FIC using a general screening strategy called rapid subtraction hybridization, and to use RT-PCR to examine differential expression three candidate genes: glucocorticoid receptor (GR), ACTH receptor (ACTHR) and corticotropin releasing factor (CRF), 2) to explore the role of DNA methylation as a mechanism of altered gene expression by comparing global methylation patterns using DNA methyl-acceptance capacity, and DNA methylation patterns in the 5' regulatory regions of genes identified using subtraction hybridization, and of the GR, ACTHR, and CRF genes. Identifying altered patterns of gene expression in a naturally occurring model of IC could significantly affect our understanding of the causes of IC, which naturally will lead to novel approaches to treatment of this condition, including tests of drugs not heretofore considered for use in these patients. More importantly, identification of the presence of this disease mechanism could lead to significant changes in public health recommendations for pregnant women and children to avoid environmental circumstances that could lead to such detrimental changes in gene expression patterns. Given the common occurrence of co-morbid disorders in patients with IC, these recommendations may be pertinent to the entire category of disorders currently lumped together as """"""""medically unexplained syndromes"""""""". ? ? ?
