The role of tissue inhibitor of metalloproteinases in the aetiology of inguinal and incisional hernias.

Inguinal and incisional hernias are the two most common types of hernias caused by abdominal wall weakness and defects in connective tissue. The structure of the extracellular matrix, mainly collagen and metalloproteinases (MMPs), and their regulators have been studied extensively and found to play a significant role in the pathophysiology of hernias. One of the regulators of MMPs, tissue inhibitor metalloproteinases (TIMPs), bind to MMPs and inhibit its activity significantly shifting the balance towards collagen synthesis rather than degradation. Due to their importance in collagen metabolism, their metabolism might be significant in the aetiology of hernias. Our study used immunohistochemical techniques to investigate the possible effects of TIMP 1 and 2 on the samples taken from the abdominal walls of patients with inguinal and incisional hernias, compared them with control patients, and reviewed the literature. In this study, samples of 90 patients (30 patients from control, inguinal hernia, and incisional hernia groups) were taken and analysed. These samples were stained with TIMP-1 Ab-2 and TIMP2 Ab-5 (Clone 3A4) antibodies and evaluated under ×100 magnification. The degree of staining was classified as (a): No staining (0), (b): Staining less than 10% (I), (c): Staining between 10% and 50% (II), (d): Staining more than 50% (III). Statistical analyses were done. No significant difference was found between groups in terms of patient demographics. Smoking and family history of hernia was not found to be associated with TIMP expression. TIMP1 expression was significantly higher in the incisional and inguinal hernia group than in the control group (P < .05), while the level of TIMP2 was higher in the control group. (P < .05). TIMP1 and TIMP2 levels did not significantly differ between incisional and inguinal hernia groups. We found significantly increased TIMP-1 levels in tissue samples from patients with hernia supporting its suggested role in hernia pathophysiology. Local alterations in MMP and TIMP levels might play a role in the pathogenesis of hernias. Thus detection of TIMP in tissues can be important for clinical use after further validation studies. In the era of molecular medicine, detecting TIMP levels in hernia patients can impact clinical practice.

A network analysis revealed the essential and common downstream proteins related to inguinal hernia.

Although more than 1 in 4 men develop symptomatic inguinal hernia during their lifetime, the molecular mechanism behind inguinal hernia remains unknown. Here, we explored the protein-protein interaction network built on known inguinal hernia-causative genes to identify essential and common downstream proteins for inguinal hernia formation. We discovered that PIK3R1, PTPN11, TGFBR1, CDC42, SOS1, and KRAS were the most essential inguinal hernia-causative proteins and UBC, GRB2, CTNNB1, HSP90AA1, CBL, PLCG1, and CRK were listed as the most commonly-involved downstream proteins. In addition, the transmembrane receptor protein tyrosine kinase signaling pathway was the most frequently found inguinal hernia-related pathway. Our in silico approach was able to uncover a novel molecular mechanism underlying inguinal hernia formation by identifying inguinal hernia-related essential proteins and potential common downstream proteins of inguinal hernia-causative proteins.

Type V Collagen is Persistently Altered After Inguinal Hernia Repair.

BACKGROUND AND AIMS: Hernia formation is associated with alterations of collagen metabolism. Collagen synthesis and degradation cause a systemic release of products, which are measurable in serum. Recently, we reported changes in type V and IV collagen metabolisms in patients with inguinal and incisional hernia. The aim of this study was to determine if the altered collagen metabolism was persistent after hernia repair. MATERIAL AND METHODS: Patients who had undergone repairs for inguinal hernia (n = 11) or for incisional hernia (n = 17) were included in this study. Patients who had undergone elective cholecystectomy served as controls (n = 10). Whole venous blood was collected 35-55 months after operation. Biomarkers for type V collagen synthesis (Pro-C5) and degradation (C5M) and those for type IV collagen synthesis (P4NP) and degradation (C4M2) were measured by a solid-phase competitive assay. RESULTS: The turnover of type V collagen (Pro-C5/C5M) was slightly higher postoperatively when compared to preoperatively in the inguinal hernia group (P = 0.034). In addition, the results revealed a postoperatively lower type V collagen turnover level in the inguinal hernia group compared to controls (P = 0.012). In the incisional hernia group, the type V collagen turnover was higher after hernia repair (P = 0.004) and the postoperative turnover level was not different from the control group (P = 0.973). CONCLUSION: Patients with an inguinal hernia demonstrated a systemic and persistent type V collagen turnover alteration. This imbalance of the collagen metabolism may be involved in the development of inguinal hernias.

Metalloproteinases and Their Inhibitors in Patients with Inguinal Hernia.

AIM: The aim of this prospective study is to investigate if there is a relationship between inguinal hernia, matrix metalloproteinases (MMPs), and tissue inhibitors of metalloproteinases (TIMPs). MATERIALS AND METHODS: This case control study was performed on patients admitted to the general surgery department of Erzincan University Hospital. Four groups were created: control, indirect hernia, direct hernia, and bilateral hernia. All groups were comprised of 11 patients. Serum and tissue levels of MMP-1, MMP-2, MMP-9, MMP-13, TIMP-1, TIMP-2, TIMP-3, and hydroxyproline were evaluated. RESULTS: MMPs values were significantly high at hernia groups, especially at bilateral hernia group (p < 0.05), whereas TIMPs values were significantly low at bilateral hernia group (p < 0.05). MMPs values were increasing at hernia groups in an order as control, indirect, direct, and bilateral. TIMPs values were decreasing at hernia groups in an order as control, indirect, direct, and bilateral. CONCLUSION: Increased levels of MMP-1-2-9-13 and decreased levels of TIMP-1-2-3 may have played role in the formation of inguinal hernia. Hernia is not only a local defect, but a reflection of systemic disease. This is even more significant for bilateral hernias.

Influence of tobacco, alcohol and diabetes on the collagen of cremaster muscle in patients with inguinal hernias / Influência do tabaco, álcool e diabete sobre a interação célula-colágeno em músculo cremaster de humanos com hérnias inguinais

ABSTRACT Background: New findings point out that the mechanism of formation of the hernias can be related to the collagenous tissues, under activity of aggressive agents such as the tobacco, alcohol and diabetes. Aim: To analyze the collagen present in the cremaster muscle in patients with inguinal hernias, focusing the effect of tobacco, alcohol, and diabetes. Methods: Fifteen patients with inguinal hernia divided in three groups were studied: group I (n=5) was control; group II (n=5) were smokers and/or drinkers; and group III (n=5) had diabetes mellitus. All subjects were underwent to surgical repair of the inguinal hernias obeying the same pre, intra and postoperative conditions. During surgery, samples of the cremaster muscle were collected for analysis in polarized light microscopy, collagen morphometry and protein. Results: The area occupied by the connective tissue was higher in groups II and III (p<0.05). The collagen tissue occupied the majority of the samples analyzed in comparison to the area occupied by muscle cells. The content of total protein was higher in groups II and III compared to the control group (p<0.05). Conclusion: The tobacco, alcohol and diabetes cause a remodel the cremaster muscle, leading to a loss of support or structural change in this region, which may enhance the occurrences and damage related to inguinal hernias.

RESUMO Racional: Estudos recentes sinalizam que o mecanismo de formação das hérnias pode estar relacionado aos tecidos colagenosos, sob a ação de agentes agressores como o tabaco, o álcool e o diabete. Objetivo: Avaliar o colágeno presente no músculo cremaster em pacientes com hérnias inguinais enfocando o efeito do tabaco, álcool e diabete. Métodos: Foram estudados 15 pacientes com hérnias inguinais divididos em: grupo I (n=5) controles; grupo II (n=5) indivíduos fumantes e/ou etilistas; e grupo III (n=5) indivíduos que apresentavam diabete melito. Todos foram submetidos à correção cirúrgica das hérnias inguinais obedecendo às mesmas condições pré, intra e pós-operatórias. Durante o procedimento cirúrgico, amostras do músculo cremaster foram coletadas para análises em microscopia de luz polarizada, morfometria do colágeno e de proteínas. Resultados: A área ocupada por tecido conjuntivo foi maior nos grupos II e III (p<0,05). O tecido colágeno ocupou a maior parte das amostras analisadas, em comparação à área ocupada pelas células musculares. O conteúdo de proteínas totais foi maior nos grupos II e III, quando comparado com o grupo controle (p<0,05). Conclusão: O tabaco, o álcool e o diabete ocasionam remodelação no músculo cremaster, levando à perda de suporte ou alteração estrutural nesta região, podendo intensificar as ocorrências e os danos relacionados às hérnias inguinais.

INFLUENCE OF TOBACCO, ALCOHOL AND DIABETES ON THE COLLAGEN OF CREMASTER MUSCLE IN PATIENTS WITH INGUINAL HERNIAS.

Background: New findings point out that the mechanism of formation of the hernias can be related to the collagenous tissues, under activity of aggressive agents such as the tobacco, alcohol and diabetes. Aim: To analyze the collagen present in the cremaster muscle in patients with inguinal hernias, focusing the effect of tobacco, alcohol, and diabetes. Methods: Fifteen patients with inguinal hernia divided in three groups were studied: group I (n=5) was control; group II (n=5) were smokers and/or drinkers; and group III (n=5) had diabetes mellitus. All subjects were underwent to surgical repair of the inguinal hernias obeying the same pre, intra and postoperative conditions. During surgery, samples of the cremaster muscle were collected for analysis in polarized light microscopy, collagen morphometry and protein. Results: The area occupied by the connective tissue was higher in groups II and III (p<0.05). The collagen tissue occupied the majority of the samples analyzed in comparison to the area occupied by muscle cells. The content of total protein was higher in groups II and III compared to the control group (p<0.05). Conclusion: The tobacco, alcohol and diabetes cause a remodel the cremaster muscle, leading to a loss of support or structural change in this region, which may enhance the occurrences and damage related to inguinal hernias.

Racional: Estudos recentes sinalizam que o mecanismo de formação das hérnias pode estar relacionado aos tecidos colagenosos, sob a ação de agentes agressores como o tabaco, o álcool e o diabete. Objetivo: Avaliar o colágeno presente no músculo cremaster em pacientes com hérnias inguinais enfocando o efeito do tabaco, álcool e diabete. Métodos: Foram estudados 15 pacientes com hérnias inguinais divididos em: grupo I (n=5) controles; grupo II (n=5) indivíduos fumantes e/ou etilistas; e grupo III (n=5) indivíduos que apresentavam diabete melito. Todos foram submetidos à correção cirúrgica das hérnias inguinais obedecendo às mesmas condições pré, intra e pós-operatórias. Durante o procedimento cirúrgico, amostras do músculo cremaster foram coletadas para análises em microscopia de luz polarizada, morfometria do colágeno e de proteínas. Resultados: A área ocupada por tecido conjuntivo foi maior nos grupos II e III (p<0,05). O tecido colágeno ocupou a maior parte das amostras analisadas, em comparação à área ocupada pelas células musculares. O conteúdo de proteínas totais foi maior nos grupos II e III, quando comparado com o grupo controle (p<0,05). Conclusão: O tabaco, o álcool e o diabete ocasionam remodelação no músculo cremaster, levando à perda de suporte ou alteração estrutural nesta região, podendo intensificar as ocorrências e os danos relacionados às hérnias inguinais.

The collagen turnover profile is altered in patients with inguinal and incisional hernia.

BACKGROUND: Disturbed metabolism in the extracellular matrix (ECM) contributes to formation of abdominal wall hernias. The aim of this study was to gain deeper insight into the ECM turnover in hernia patients by analyzing serum biomarkers specifically reflecting collagen synthesis and breakdown in the interstitial matrix (types I, III, and V collagens) and in the basement membrane (type IV collagen). MATERIAL AND METHODS: Patients with 3 different types of hernias were included: Primary unilateral inguinal hernia (n = 17), multiple hernias defined as ≥3 hernias (n = 21), and incisional hernia (n = 25). Patients without hernias scheduled to undergo elective operation for gallstones (n = 18) served as controls. Whole venous blood was collected preoperatively. Biomarkers for synthesis of interstitial matrix (PINP, Pro-C3, P5CP) and basement membrane (P4NP) as well as corresponding degradation (C1M, C3M, C5M, and C4M) were measured in serum by validated, solid-phase competitive assays. RESULTS: In inguinal hernia patients, the turnover of the interstitial matrix collagens type III (P < .042) and V (P < .001) was decreased compared with controls, whereas the turnover of the basement membrane collagen type IV was increased (P < .001). In incisional hernia patients, the turnover of type V collagen was decreased (P = .048) and the turnover of type IV collagen was increased compared with the hernia-free controls (P < .001). CONCLUSION: Hernia patients demonstrated systemically altered collagen metabolism. The serologic turnover profile of type IV collagens may predict the presence of inguinal and incisional hernia. Regulation of type IV collagen turnover may be crucial for hernia development.

Evaluation of antioxidative/oxidative status and prolidase parameters in cases of inguinal hernia with joint hypermobility syndrome.

PURPOSE: Most previous reports have shown that the basic mechanism of inguinal hernia involves insufficient collagen strength and metabolism. The aim of this study was to evaluate whether joint hypermobility is involved in the development of inguinal hernia in children and to investigate oxidative stress parameters and prolidase activity in tissue samples from children with inguinal hernia. METHODS: This cross-sectional study involving 41 patients (age, 6.36 ± 2.96 years) with inguinal hernia treated in the pediatric surgery department of our institution and 40 age- and sex-matched controls (age, 6.02 ± 3.13 years) was performed from May to December 2011. Joint hypermobility was assessed using the Beighton criteria in all patients. Hernia sacs were analyzed with respect to the total antioxidative/oxidative status and prolidase activity. The patients were divided into two groups (inguinal hernia with and without hypermobility) according to a Beighton score cut-off of ≥6. RESULTS: A total of 81 subjects aged 3-10 years participated. The ratio of joint hypermobility was significantly higher in patients than in controls (p = 0.01). The prolidase activity, total oxidant status, and oxidative stress index were higher in tissue samples from patients with joint hypermobility (p < 0.001). CONCLUSIONS: Our results show that joint hypermobility syndrome is associated with inguinal hernia in children and that increased prolidase activity and oxidative stress in tissue samples from patients with joint hypermobility syndrome are related to collagen tissue damage and turnover.

Measurement of hydroxyproline and nitric oxide, and comparison of sac fluid acidity in different inguinal pathologies.

PURPOSE: To compare hydroxyproline and nitric oxide levels, and fluid acidity between sac tissues from inguinal hernia, hydrocele and undescended testis patients. MATERIAL AND METHOD: Thirty patients were in the inguinal hernia group, 11 patients in the hydrocele group and 5 patients in the undescended testis with inguinal hernia group. Intrasaccular fluid acidity, and nitric oxide and hydroxyproline levels in sac tissues were measured and analyzed statistically between groups. RESULTS: Intrasaccular fluid could be obtained from 24 inguinal hernia and 6 hydrocele patients. Acidity level (pH) was 7.5 ± 0.74 in the hernia group and 7.86 ± 0.63 in the hydrocele group (p < 0.05). All patients in the three groups were evaluated for nitric oxide and hydroxyproline. Results for hydroxyproline (mg/g dry tissue)/nitric oxide (nmol/g wet tissue) were 3.53 ± 0.54/2.02 ± 0.39 for inguinal hernia, 2.89 ± 0.9/1.92 ± 1.05 for hydrocele and 3.02 ± 1.23/2.86 ± 1.09 for undescended testis group (p > 0.05). CONCLUSION: Hydroxyproline and nitric oxide pathways do not seem to be responsible for the different characteristics of inguinal diseases. However, differences in the acidity of sac fluid may be evidence of the different mechanisms of hernia and hydrocele formation.

Expression of anti-Mullerian hormone receptor on the appendix testis in connection with urological disorders.

The female internal sex organs develop from the paramesonephric (Mullerian) duct. In male embryos, the regression of the Mullerian duct is caused by the anti-Mullerian hormone (AMH), which plays an important role in the process of testicular descent. The physiological remnant of the Mullerian duct in males is the appendix testis (AT). In our previous study, we presented evidence for the decreased incidence of AT in cryptorchidism with intraoperative surgery. In this report, the expression of the anti-Mullerian hormone receptor type 2 (AMHR2), the specific receptor of AMH, on the AT was investigated in connection with different urological disorders, such as hernia inguinalis, torsion of AT, cysta epididymis, varicocele, hydrocele testis and various forms of undescended testis. The correlation between the age of the patients and the expression of the AMHR2 was also examined. Reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry were used to detect the receptor's mRNA and protein levels, respectively. We demonstrate that AMHR2 is expressed in the ATs. Additionally, the presence of this receptor was proven at the mRNA and protein levels. The expression pattern of the receptor correlated with neither the examined urological disorders nor the age of the patients; therefore, the function of the AT remains obscure.

Matrix metalloproteinase imbalance in inguinal hernia formation.

BACKGROUND: Emerging evidence supports the role of matrix metalloproteinases (MMPs) in hernia formation. However, the imbalance between the proteolytic activity of MMPs and their endogenous inhibitors (TIMPs) has not been investigated. The aim of the present study was to determine changes of MMP and TIMP levels in patients with inguinal hernia. METHODS: Two matrix metalloproteinases (MMP-9 and MMP-2) and their main inhibitors TIMP-1 and TIMP-2 were evaluated in consecutive patients undergoing inguinal hernia repair and control subjects. MMP/TIMP quantification was performed using ELISA in abdominal fascia tissue specimens and preoperative plasma samples. RESULTS: Tissue explants from hernia patients produced significantly higher levels of MMP-9 and MMP-2, and reduced TIMP-1 and TIMP-2 concentrations compared to those of controls. In plasma, a reverse correlation was found regarding the concentrations of MMPs; the circulating levels of MMP-9 and MMP-2 were significantly lower in patients with inguinal hernia than controls. Furthermore, hernia patients were found to have elevated plasma levels of TIMP-2 and reduced plasma levels of TIMP-1. CONCLUSIONS: The imbalance in MMP/TIMP activity indicates a dysregulation of the extracellular matrix degradation process in patients with inguinal hernia. The results of the present study suggest that impaired collagen metabolism may be an underlying pathophysiological mechanism of inguinal hernia formation.

The value of copper and zinc levels in hernia formation.

BACKGROUND: A defect in collagen metabolism is suspected to be one of the factors responsible for hernia formation. Lysyl oxidase is a copper-dependent enzyme in the process that provides for the structural integrity of collagen molecules, while zinc is essential for tissue maintenance. MATERIALS AND METHODS: In a prospective fashion, copper and zinc levels were measured in plasma and tissue specimens obtained from indirect (n=23), direct (n=20) and incisional hernia patients (n=19) and from healthy controls (laparoscopic cholecystectomy patients, n=15) by enzymatic colorimetric analysis. RESULTS: Groups were similar in age, comorbid diseases and body mass index. Whereas plasma levels of Cu and Zn in hernia and control patients were similar, and tissue levels were significantly lower in all hernia groups (especially the incisional hernia group) compared to controls (P<0·001). The incisional hernia group had significantly lower tissue copper levels than direct hernia patients and lower zinc levels than indirect hernia patients. CONCLUSIONS: Patients with all types of hernia, especially those with incisional hernias, have significantly lower tissue copper and zinc levels than control patients, despite having similar plasma levels. This finding might reflect excessive consumption or dysfunction of lysyl oxidase as playing a role in the aetiology of hernias.

Active matrix metalloproteinase-2 upregulation in the abdominal skin of patients with direct inguinal hernia.

BACKGROUND: Prior studies suggest impaired collagen metabolism involving the whole abdominal wall including the skin in patients with abdominal hernia. We compared expression patterns of matrix metalloproteinase-2 (MMP-2) and its modulators membrane type-1-matrix metalloproteinase (MT-1 MMP) and tissue inhibitor of metalloproteinase-2 (TIMP-2) in the skin of patients with and without primary inguinal hernia. MATERIALS AND METHODS: Skin biopsy specimens from abdominal wall incisions were obtained during surgery from patients with direct inguinal hernia, indirect inguinal hernia or without hernia (controls). MMP-2, MT-1 MMP and TIMP-2 expression were determined using immunocytochemistry and immunoblotting in intact tissue and in cultured fibroblasts isolated from the biopsies. The degradation activity of MMP-2 was semiquantitatively determined using zymography. RESULTS: Significantly greater active MMP-2 expression was observed in skin fibroblasts obtained from patients with direct hernia compared with controls. MT1-MMP expression was directly correlated with MMP-2 expression with most intense staining produced in patients with direct or indirect inguinal hernia. TIMP-2, was maximally expressed in the control group, with significantly diminished expression levels recorded in the hernia groups. CONCLUSIONS: Our findings indicate active MMP-2 upregulation in the abdominal skin of patients with direct inguinal hernia. This metalloproteinase plays a role in matrix degradation, weakening the abdominal wall. Skin disorders and previously described transversalis fascia defects in these patients could point to a systemic collagen metabolism abnormality as a risk factor for direct hernia.

Smooth muscle cell differentiation in the processus vaginalis of children with hernia or hydrocele.

PURPOSE: Incomplete obliteration of the processus vaginalis (PV) in children with inguinal hernia or hydrocele has recently been proposed to relate to smooth muscle cell (SMC) persistence. The aim of this study was to evaluate the diversity and differentiation of smooth muscle phenotypes in sacs associated with inguinal hernia and hydrocele through the expression of alpha-smooth muscle actin (SMA), h-caldesmon, desmin, and vimentin. METHODS: Sacs associated with male hernia (n = 22), female hernia (n = 8), and hydrocele (n = 10) were immunohistochemically evaluated using monoclonal antibodies against SMA, h-caldesmon, desmin, and vimentin. Peritoneal samples (male, 4; female, 3) and obliterated PV (male, 3) obtained from age-matched patients served as controls. Expressions according to the groups were compared through chi-squared test, and P values less than 0.05 were considered to be statistically significant. RESULTS: Immunohistochemistry did not shown the presence of SMCs in control samples. The expression of SMA, desmin, and h-caldesmon did not differ among sacs obtained from patients with inguinal hernia and hydrocele. However, strong expression of vimentin in SMCs within sacs obtained from patients with hydrocele in comparison with sacs from male patients with inguinal hernia were observed. CONCLUSIONS: Our results indicate that sacs from patients with inguinal hernias and especially from male inguinal hernias have fully differentiated SMCs. On the other hand SMCs in sacs obtained from boys with hydrocele are in an intermediate state of differentiation-dedifferentiation. This phenotypic modulation may represent attempted apoptosis of SMCs, since sacs more sensitive to apoptosis appeared to have more dedifferentiated SMCs. It also probably depicts the differing influence of sympathetic and parasympathetic tonuses during the descent of the testis and the obliteration of PV.

Looking past the lump: genetic aspects of inguinal hernia in children.

Inguinal hernia is associated with a multitude of genetic syndromes. Disorders of the microfibril, elastin, collagen, and the glycosaminoglycan component of the extracellular matrix can result in an increase in the likelihood of inguinal hernia. In addition, inguinal hernia may be the presenting feature of disorders of sexual differentiation. Inguinal hernia of unknown etiology also occurs more commonly in several other groups of genetic diseases including chromosomal disorders, microdeletion disorders such as 22q11.2 microdeletion, and in single gene disorders. We review the genetics of connective tissue formation and focus on a series of genetic conditions that may present with or are characterized by a higher risk of inguinal hernia. A comprehensive review of the literature aims to provide a diagnostic framework to aid in the identification of patients with inguinal hernia as part of underlying genetic disease.

Lysyl oxidase like-1 dysregulation and its contribution to direct inguinal hernia.

OBJECTIVE: The aetiology of inguinal hernia involves changes in collagen turnover and metalloproteinase expression; yet it is not known whether the elastic fibre system could also be affected. This study was designed to compare the expression of tropoelastin (TE), lysyl oxidase-like 1 (LOXL-1) and elastase in the transversalis fascia of patients with and without inguinal hernia. MATERIAL AND METHODS: Transversalis fascia (TF) specimens were obtained from patients undergoing surgery for direct or indirect inguinal hernia (n = 20 each) and from multi-organ donors during organ procurement (controls, n = 16). The specimens were divided according to age (20-40/41-60 years). Tissues were immunohistochemically labelled using anti-tropoelastin, anti-LOXL-1 and anti-elastase antibodies and subjected to Western blot analysis. Relative amounts of LOXL-1 and TE mRNA were determined by real time RT-PCR in cultured cells obtained from the TF of patients and controls. RESULTS: Significantly lower TE and LOXL-1 levels were observed in patients with direct inguinal hernia compared with controls or those with indirect hernia. In contrast, patients with direct inguinal hernia showed significantly higher elastase expression. In fibroblasts isolated from the TF, relative amounts of tropoelastin mRNA were lower for the hernia groups but differences were not significant. LOXL-1 mRNA levels were significantly lower in the direct hernia group compared to controls. CONCLUSIONS: Our findings suggest that impaired elastic fibre function in the transversalis fascia of patients with direct inguinal hernia, reflected by diminished elastin synthesis and its enhanced enzyme degradation, contributes to the development of this type of hernia.

[Hernias as medical disease]. / Hernier som medicinsk sygdom.

Abnormal systemic collagen metabolism is thought to dispose to the development of hernias. Studies have shown that a reduced type-I/III collagen ratio predisposes to the development of hernias. Patient groups with reduced type-I/III collagen ratio and consequently increased risk of herniation include patients with Ehlers-Danlos, Marfans syndrome, osteogenesis imperfecta, cutis laxa, and patients with abdominal aortic aneurysms, colonic diverticula or stress urinary incontinence. Looking ahead, the perspective may be individualization of the operative technique for patients with a hernia, depending on their collagen profile.

Evaluation of extracellular matrix protein composition in sacs associated with undescended testis, hydrocele, inguinal hernia, and peritoneum.

OBJECTIVES: To investigate and compare the distribution and intensity of staining of extracellular matrix proteins--laminin, fibronectin, and types 1 and 4 collagen--in various congenital inguinoscrotal abnormalities and the peritoneum through immunohistochemical staining. METHODS: The sacs associated with undescended testis (n = 28), hydrocele (n = 29), inguinal hernia (n = 31), and parietal peritoneum (n = 28) were stained with antibodies for laminin, fibronectin, and types 1 and 4 collagen. The peritoneum served as the control group. Appropriate tissue sections of each group of samples were identified and compared with regard to the intensity and distribution of staining. RESULTS: The expression of laminin was significantly greater in the sacs associated with undescended testes and inguinal hernia than in the peritoneum. The expression pattern of fibronectin did not differ in the sacs of the different inguinoscrotal abnormalities compared with peritoneum. Type 1 collagen was strongly expressed in the sacs obtained from the hydroceles compared with the other groups and the peritoneum. Expression of type 4 collagen was significantly increased in the sacs associated with hydrocele and inguinal hernia compared with the peritoneum. CONCLUSIONS: The distribution and expression of laminin and types 1 and 4 collagen showed variability in the sacs associated with undescended testis, hydrocele, and inguinal hernia and the peritoneum. The tensile forces that the sacs associated with childhood inguinoscrotal abnormalities are exposed to per se could account for some of the differences seen between the inguinoscrotal tissues and anterior peritoneum. These differences in the extracellular matrix proteins could also reflect congenital properties of various childhood inguinoscrotal abnormalities.