痔发病机制的分子生物学研究进展

Progress in pathogenesis of hemorrhoids:research of molecular biology

目的了解痔发病机制的分子生物学研究进展。方法对近年来国内外关于痔发病机制的分子生物学方面研究的相关文献进行综述。结果目前比较公认的痔发病理论有肛垫下移学说、静脉曲张学说、血管增生学说。肛垫下移学说的相关分子生物学研究发现,基质金属蛋白酶-9表达增加、血管壁平滑肌肌动蛋白表达异常可损伤肛垫支持组织,从而造成肛垫下移并脱出,进而形成痔;静脉曲张学说的相关分子生物学研究发现,一氧化氮合酶、辣椒素受体增加可促进一氧化氮产生,从而引起静脉曲张,进而导致痔发病;新血管生成学说的相关分子生物学研究发现,微小RNAs miR-412-5p和miR-4729表达下调,血管内皮生长因子、成纤维细胞生长因子过表达与痔组织的新血管生成有关。此外,痔发病后的继发炎症反应也在痔的发生及发展中发挥重要作用。结论痔的发生及发展是肛垫下移、静脉曲张、血管增生、继发炎症反应等多种机制相互交叉、相互影响的结果,对痔发病机制的分子生物学研究有助于从微观角度更好地解释痔的发生,为进一步探索痔的病因奠定基础。

Objective To understand the progress of molecular biology research on the pathogenesis of hemorrhoids.Method The literatures relevant to reseaches on the molecular biology of hemorrhoid pathogenesis in recent years had been reviewed.Results The generally accepted theories of hemorrhoids included anal cushion downward movement theory,varicose vein theory,and vascular proliferation theory.The molecular biological studies related to the theory of anal cushion downward movement found that the increased expression of matrix metalloproteinase-9and the abnormal expression of smooth muscle actin could damage the supporting tissue of anal cushion,causing the downward movement and prolapse of anal cushion,and then formed hemorrhoids;The molecular biology researches related to varicose vein theory found that the increase of nitric oxide synthase and transient receptor potential vanilloid 1could promote the production of nitric oxide,causing varicose veins,and then leaded to the pathogenesis of hemorrhoids;The molecular biology researches related to vascular proliferation theory found that the low expressions of miR-412-5p and miR-4729,and the overexpressions of vascular endothelial growth factor and fibroblast growth factor were related to the vascular proliferation of hemorrhoids.In addition,the secondary inflammatory reaction after the onset of hemorrhoids also played an important role in the occurrence and development of hemorrhoids.Conclusions The occurrence and development of hemorrhoids is the result of the intersection and interaction of various mechanisms such as anal cushion downward movement,varicose veins,vascular proliferation,and secondary inflammatory reaction.The molecular biology research on the pathogenesis of hemorrhoids is helpful to better explain the occurrence of hemorrhoids from a microcosmic perspective,and lay a foundation for further exploring the etiology of hemorrhoids.