PubMed · 7606050
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
M J Wilson. 1995-03-01. Proteases in prostate development, function, and pathology.. https://doi.org/10.1002/jemt.1070300406
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Dysregulated nitric oxide (NO) signaling contributes to the pathogenesis of hypertension, a prevalent and often sex-specific risk factor for cardiovascular disease. We previously reported that mice deficient in the α1-subunit of the NO receptor soluble guanylate cyclase (sGCα1 (-/-) mice) display sex- and strain-specific hypertension: male but not female sGCα1 (-/-) mice are hypertensive on an 129S6 (S6) but not a C57BL6/J (B6) background. We aimed to uncover the genetic and molecular basis of the observed sex- and strain-specific blood pressure phenotype. Via linkage analysis, we identified a suggestive quantitative trait locus associated with elevated blood pressure in male sGCα1 (-/-)S6 mice. This locus encompasses Cyp4a12a, encoding the predominant murine synthase of the vasoconstrictor 20-hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE). Renal expression of Cyp4a12a in mice was associated with genetic background, sex, and testosterone levels. In addition, 20-HETE levels were higher in renal preglomerular microvessels of male sGCα1 (-/-)S6 than of male sGCα1 (-/-)B6 mice. Furthermore, treating male sGCα1 (-/-)S6 mice with the 20-HETE antagonist 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid (20-HEDE) lowered blood pressure. Finally, 20-HEDE rescued the genetic background- and testosterone-dependent impairment of acetylcholine-induced relaxation in renal interlobar arteries associated with sGCα1 deficiency. Elevated Cyp4a12a expression and 20-HETE levels render mice susceptible to hypertension and vascular dysfunction in a setting of sGCα1 deficiency. Our data identify Cyp4a12a as a candidate sex-specific blood pressure-modifying gene in the context of deficient NO-sGC signaling.
In mice, cysteine-rich secretory protein-1 (CRISP-1) is mainly found in the epididymis and also, to a lesser extent, in the salivary gland of males, where androgens control its expression. We have now isolated and characterized overlapping phage clones covering the entire length of the CRISP-1 gene. DNA sequencing revealed that the gene is organized into eight exons, ranging between 55 and 748 bp in size, and seven introns. All exon-intron junctions conformed to the GT/AG rule established for eukaryotic genes. The intron length, as determined by PCR, varied between 1.05 and 4.0 kb so that the CRISP-1 gene spans over 20 kb of the mouse genome. The transcription-initiation site was determined by primer extension and localized at the expected distance downstream of a consensus TATA box. Approximately 3.7 kb of the CRISP-1 promoter region were isolated and sequenced, and several stretches fitting the androgen-responsive element consensus were found. Those that most resembled the consensus were analysed by electrophoretic mobility-shift assay and found to form specific complexes with the liganded androgen receptor in vitro, but with different affinities. Putative binding elements for the transcription factors Oct, GATA, PEA3, CF1. AP-1 and AP-3 were also found in the promoter region.
To assess the function of androgen receptor in androgen-independent prostate cancer cells, human PC-3 prostate carcinoma cells, which lack androgen receptor (AR) expression, were transfected with a full length human AR cDNA sequence inserted into an episomal expression vector system. Several clonal lines of transfected cells expressing varying levels of a 110 kDa AR, as determined by immunoblotting and ligand binding assay, were isolated. The expressed ectopic receptors displayed nuclear binding following androgen treatment and mediated androgen inducibility of a mouse mammary tumor virus (MMTV)-luciferase reporter gene construct in a dose-dependent manner. 5 alpha-dihydrotestosterone (DHT) activation of luciferase activity was blocked by the AR antagonist hydroxyflutamide, and was promoter-specific based on the inability of the hormone-insensitive RSV promoter to respond to DHT. Treatment of AR-expressing PC-3 cells with physiological levels of DHT for 3 days resulted in paradoxical inhibition of cell growth. The growth-inhibitory effect was observed in clonal lines expressing low, moderate and high levels of AR, indicating that it was not the result of AR overexpression. To determine whether AR-expressing PC-3 cells had become androgen dependent, albeit with slowed growth, the effect of 1.0 nM DHT on the growth of two clonal lines expressing low and moderate receptor levels (PC-3(AR)13 and PC-3(AR)2, respectively) was examined on over an 18 day period. DHT removed after 3, 6, or 9 days and replaced with steroid-free medium. Surprisingly, after 6 days of DHT treatment, the number of PC-3(AR)2 cells began to decrease such that all cells were dead by 15 days after initiation of DHT treatment. A similar effect was observed in PC-3(AR)13 cells, but required a longer initial period of DHT exposure. PC-3(AR)2 cells were rescued from cell death if DHT was withdrawn 3 days but not 6 or 9 days after initiation of DHT treatment. As determined by DNA cell cycle analysis, the proportion of cells in the G1 phase was enhanced by DHT treatment, accompanied by a decrease in cells in the S and G2M phase of the cell cycle. After 6 days of DHT treatment, the proportion of cells in G1 decreased which was accompanied by an increase in cells in a subG1 population consistent with apoptosis. DNA fragmentation in PC-3(AR)2 cells after 3 or 6 days of DHT treatment was demonstrated by agarose gel electrophoresis, further indicating the cell death was apoptotic. Removal of DHT from PC-3(AR)2 cultures after 3 days, but not after 6 or 9 days, was followed by a large shift in cells from G1 to S and G2M. These data suggest that DHT blocks the progression of AR transfected PC-3 cells through the cell cycle, resulting in growth inhibition and apoptosis.