Slayden Ov D, Hettrich Kevin, Carroll Rebecca S, Otto Lesley N, Clark Amanda L, Brenner Robert M
Oregon National Primate Research Center, Beaverton, Oregon 97006, USA.
J Clin Endocrinol Metab. 2004 Feb;89(2):883-91. doi: 10.1210/jc.2003-031143.
Cystatin C is a secreted inhibitor of cysteine proteinases that participates in extracellular matrix remodeling. Whether hormones affect its expression in the vagina was unknown. Consequently, we examined the effects of estradiol (E(2)), progesterone (P), and raloxifene on vaginal cystatin C in rhesus macaques. In experiment 1, ovariectomized animals were treated sequentially with E(2) (14 d) and E(2) + P (14 d) to induce 28-d menstrual cycles. Vaginal samples were collected on d 6, 8, 14, and 28 of the induced cycle. Some cycled animals were deprived of both E(2) + P for 28 d. In experiment 2, ovariectomized animals were treated for 5 months with E(2) alone, E(2) + P, raloxifene, or left untreated. Total RNA from the vaginal wall was analyzed for the cystatin C transcript with a commercially prepared cDNA array and semiquantitative RT-PCR. Vaginal cryosections were analyzed by in situ hybridization for cystatin C transcript and by immunocytochemistry for the protein. E(2) treatment significantly (5-fold; P < 0.05) increased expression of cystatin C transcript over the levels in the hormone-deprived controls, and cotreatment with P (E(2) + P) blocked this effect. Raloxifene treatment did not affect cystatin C expression. In situ hybridization and immunocytochemistry revealed that cystatin C was localized in fibroblasts and smooth muscle cells throughout the vaginal wall but not in smooth muscle cells of arteries or levator ani myocytes. In summary, E(2) increased vaginal cystatin C expression in the fibroblasts and smooth muscle bundles, P suppressed this effect, and raloxifene had no effects on cystatin C. Elevated cystatin C, by suppressing cysteine proteinase activity, may strengthen the vaginal wall and mitigate the potential for pelvic floor prolapse.
胱抑素C是一种分泌型半胱氨酸蛋白酶抑制剂，参与细胞外基质重塑。激素是否影响其在阴道中的表达尚不清楚。因此，我们研究了雌二醇（E₂）、孕酮（P）和雷洛昔芬对恒河猴阴道胱抑素C的影响。在实验1中，对去卵巢动物依次给予E₂（14天）和E₂ + P（14天）以诱导28天的月经周期。在诱导周期的第6、8、14和28天收集阴道样本。一些周期性动物在28天内同时停用E₂ + P。在实验2中，对去卵巢动物分别单独用E₂、E₂ + P、雷洛昔芬治疗5个月，或不进行治疗。使用市售的cDNA芯片和半定量RT-PCR分析阴道壁的总RNA中的胱抑素C转录本。通过原位杂交分析阴道冰冻切片中的胱抑素C转录本，并通过免疫细胞化学分析蛋白质。与激素剥夺的对照组相比，E₂治疗显著（5倍；P < 0.05）增加了胱抑素C转录本的表达，而与P共同治疗（E₂ + P）则阻断了这种作用。雷洛昔芬治疗不影响胱抑素C的表达。原位杂交和免疫细胞化学显示，胱抑素C定位于整个阴道壁的成纤维细胞和平滑肌细胞中，但不存在于动脉平滑肌细胞或肛提肌细胞中。总之，E₂增加了成纤维细胞和平滑肌束中阴道胱抑素C的表达，P抑制了这种作用，而雷洛昔芬对胱抑素C没有影响。通过抑制半胱氨酸蛋白酶活性，升高的胱抑素C可能会增强阴道壁并减轻盆底脱垂的可能性。
