Alteraciones de la matriz extracelular del tejido conectivo en el proceso de herniogénesis inguinal

AbstractInguinal hernia is still today one of the entities that most frequently requires surgical treatment. The techniques for surgical repair are around 20% of all general surgery procedures. Although its etiology remains unclear, there seem to be many contributing factors added to an individual predisposition.The aetiology of inguinal hernia involves changes in the expression of different extracellular matrix constituents, affecting especially at the level of the transversalis fascia (TF), such as collagen, elastic component and Metalloproteinases (MMPs).This work aims to make a review of all the alterations that affect connective tissue and the extracellular matrix, which take place at the level of the inguinal region.In previous studies, we were able to demonstrate the overexpression of MMP-2 in the transversalis fascia of young patients with direct inguinal hernia correlated with the overexpression of TGF-beta1 showing an attempt to counterbalance the enhanced matrix degradative process observed in these patients. At the level of the elastic tissue of the TF, direct inguinal hernia patients show low levels of tropoelastin (TE), precursor to the elastin molecule and lysyl oxidase like-1 (LOXL-1), enzyme involved in cross-linking of elastin. In contrast, these patients showed significantly higher elastase expression, main enzyme involved in the process of degradation of elastin. Significantly lower LOXL-1 mRNA levels were also observed in cells obtained from the TF of patients with direct inguinal hernia.All these alterations highlight a disorder at the level of the extracellular matrix of connective tissue in patients with inguinal hernias, which together with other exogenous factors (smoking, mechanical stress, aging of tissues…) would partly explain the genesis of this pathology