The Expressions And Significance Of MMP-2 And TIMP-2 In Skin Of Inguinal Hernia

Background and objectiveInguinal hernia is one of the most common diseases in abdominal general surgery. However, the exact reason of the development in inguinal hernia has not been completely determined. Over the years many persons consider the main etiological factors of inguinal hernia are the anatomic (the lower intension of abdominal wall) and dynamic (the higher intraabdominal pressure). And many scholars believe that the reason of adult inguinal hernia is weakness and defect in transverse fascia.In recent years, some scholars have introduced biochemical of organization, the doctrine of collagen metabolism:a decreased ratio of relative amount ofâ… /â…¢collagen(low typeâ… collagen and relatively height typeâ…¢collagen) deduce ransverse fascia weakness.Matrix metalloproteinases (MMPs) and tissue inhibitor of matrix metalloprotei-nases(TIMPs) are main regulation enzymes in collagen metabolism, which play a most important role in maintaining the stability and mechanical integrity of the ECM.MMPs are a group of endopeptidase depended on Zn2+ synthetized and secreted by fibroblasts, and are the principal enzyme involved with collagen degradation.More than 20 MMPs had been discovered up to now, which constitute MMPs family for highly homology.Generally,MMPs take part in the metabolism of typeâ… ,â…¢collagen fiber,majorly the cross linkage and maturation of new synthetic collagen fiber and the occurrence of henia.TIMPs are the natural inhibitors of MMPs discovered for the past few years,which can combind with MMPs according to the ratio of 1:1 and TIMPs inhibit MMPs activity in the extracellular space.As can be seen,MMPs and TIMPs play a significantly important role in maintaining collagen stabilize,and take a certain part in the generation and recurrence of inguinal hernia.At present there were few studies of MMPs and TIMPs in inguinal hernia and those finding must be certified further. In this study the expressions of MMP-2mRNA and TIMP-2 mRNA in the skins derived from patients with inguinal hernias and from patients without inguinal hernia were detected by transcription polymerase chain reaction (RT-PCR) and analysed.The aim of this study is to investigate whether a systemical facters are associated with the development of adult primary inguinal hernia,and investigate whether an alteration in collagen enzymes metabolic are associated with the adult primary inguinal hernia developingt.We expect the experimental result will provide some favourable rationales based on molecular mechanism of inguinal hernia, and scientific for effective treatments in inguinal hernia.Materials and methodsExperimental group and control group are designed in this experiment, the inguinal hernias are designed as experiment control with the no hernias, all the materials are the skins of posterior wall. Because TIMPs and MMPs are synthesized and secreted by fibroblasts what are most abundant in the skin.Experimental group:The date of 50 cases that underwent primary hernia repair from July 2009 and November 2009 in the First Affiliated Hospital of Zhengzhou University.There are 31 inderect hernias and 19 derect hernias.Control group:The date of 50 cases come from the same hospital at the same time as the experimental group.All of materials are the skins of posterior wall.The expression of MMP-2mRNA,TIMP-2mRNA were detected by reverse transcription polymerase chain reaction (RT-PCR) method. SPSS13.0 statistical software was used for statistical analysis. For numeric data, differences were analyzed by analysis of variance and t test, linear correlation was applied between two variables. The P value of less than 0.05 was considered statistieally.ResultBoth groups can be detected the expression of MMP-2mRNA,TIMP-2mRNA.1 The expression level of MMP-2mRNA in the experimental group(direct hernias)are higher (p=0.025<0.05) while the expression levels of TMMP-2mRNA are lower (p=0.031<0.05) than the control group (non-hernias group) in statistics difference. 2 The expression levels of MMP-2mRNA and TIMP-2mRNA in the experimental group(direct hernias) and the control group (non-hernias) groups do not show any significant difference (PMMP-2=0.055>0.05) (PTIMP-2=0.073>0.05)3 The expression level of MMP-2mRNA in the long-term smokers are higher (p=0.023<0.05) while the expression level of TMMP-2mRNA are lower (p=0.041< 0.05) than the not long-term smokers in statistics difference.4 The expression level of MMP-2mRNA in the skins are positive correlation to the age(r=0.227, P=0.041<0.05)which increase with the age. The expression level of TIMP-2mRNA in the skins are negative correlation to the age(r=-0.372, P=0.014 <0.05) which decrease with the age.5 The expression level of MMP-2mRNA are positive correlation to the TIMP-2mRNA (r=-0.629, P=0.037<0.05) in the skins, The expression level of MMP-2mRNA decrease as lang as the expression levels of TIMP-2mRNA.Conclusion1 The higher expression of MMP-2mRNA and the lower expression of MMP-2mRNA in direct hernias indicate that MMP-2 and TIMP-2 involve in the regulation of collagen and procede the adult primary direct hernia.2 The expression of MMP-2mRNA and TIMP-2mRNA in the experimental group(direct hernias) and the control group (non-hernias) groups do not show any significant difference indicate that those are not relation to indirect hernia.3 The height expression of MMP-2mRNA and the low expression of TIMP-2m-RNA in the long-term smokers indicate that smoking may be one of the reason in developing of inguinal hernia.4 The positive correlation expression level of MMP-2mRNA and the negative correlation expression level of TIMP-2mRNA to the age indicate that the older the higher incidence of inguinal hernia.5 The expression level of MMP-2mRNA are positive correlation to the TIMP-2mRNA indicate that the expression of TIMP-2 inhibit the expression of TIMP-2.Both of them might participate the collagen metabolism and developing of primary inguinal hernia.