Peralta M B, Baravalle M E, Belotti E M, Stassi A F, Salvetti N R, Ortega H H, Rey F, Velázquez M M L
Instituto de Ciencias Veterinarias del Litoral, Universidad Nacional del Litoral, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Esperanza, Santa Fe, Argentina.
Instituto de Ciencias Veterinarias del Litoral, Universidad Nacional del Litoral, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Esperanza, Santa Fe, Argentina.
J Comp Pathol. 2017 Feb-Apr;156(2-3):191-201. doi: 10.1016/j.jcpa.2016.10.012. Epub 2016 Dec 18.
The most important regulators of tissue remodelling during ovarian follicular growth, development, ovulation and atresia are gonadotropins, steroid hormones, growth factors and different proteolytic enzymes. Matrix metalloproteinases (MMPs) such as collagenase or gelatinase (i.e. MMP-1, -8, -2 and -9) and associated tissue inhibitors of metalloproteinases (TIMP-1, -2, -3 and -4) control connective tissue remodelling during follicular rupture. In this study, we hypothesized that an imbalance in the MMP-TIMP system may be an intra-ovarian component that contributes to the pathogenesis of cystic ovarian disease (COD) in cows. Taking into account that the control of MMP activity by TIMPs could determine their effects in both physiological and pathological conditions, MMP and TIMP mRNA and protein expression was examined by real-time polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC), respectively, in ovaries from control cows and cows with COD. Expression of mRNA encoding MMP-2, TIMP-1 and TIMP-2 was lower in follicular cysts than in control pre-ovulatory follicles, while the results by IHC showed this imbalance only for TIMP-2 protein expression. Additional analysis by zymography to evaluate the gelatinase activity of MMP-2 and MMP-9 demonstrated higher MMP-2 activity in follicular fluid (FF) of cysts than in FF of pre-ovulatory follicles. On the other hand, MMP-9 activity was increased in follicular cysts and absent in the FF of pre-ovulatory follicles. These findings suggest that the altered mRNA expression and activities of the MMP-TIMP system may be related to the failure in ovulation and follicular development observed in COD.
在卵巢卵泡生长、发育、排卵和闭锁过程中，组织重塑的最重要调节因子是促性腺激素、类固醇激素、生长因子和不同的蛋白水解酶。基质金属蛋白酶（MMPs），如胶原酶或明胶酶（即MMP - 1、- 8、- 2和- 9）以及相关的金属蛋白酶组织抑制剂（TIMP - 1、- 2、- 3和- 4）控制卵泡破裂过程中的结缔组织重塑。在本研究中，我们假设MMP - TIMP系统的失衡可能是奶牛卵巢囊肿性疾病（COD）发病机制中的一个卵巢内因素。考虑到TIMP对MMP活性的控制可能决定它们在生理和病理条件下的作用，分别通过实时聚合酶链反应（RT - PCR）和免疫组织化学（IHC）检测了对照奶牛和患有COD的奶牛卵巢中MMP和TIMP的mRNA及蛋白表达。卵泡囊肿中编码MMP - 2、TIMP - 1和TIMP - 2的mRNA表达低于对照排卵前卵泡，而免疫组织化学结果仅显示TIMP - 2蛋白表达存在这种失衡。通过酶谱分析进一步评估MMP - 2和MMP - 9的明胶酶活性，结果表明囊肿卵泡液（FF）中的MMP - 2活性高于排卵前卵泡的FF。另一方面，卵泡囊肿中MMP - 9活性增加，而排卵前卵泡的FF中不存在该活性。这些发现表明，MMP - TIMP系统mRNA表达和活性的改变可能与COD中观察到的排卵和卵泡发育失败有关。
