Comparison of interleukin-6 and matrix metalloproteinase expression in the subretinal fluid and the vitreous during proliferative vitreoretinopathy: correlations with extent, duration of RRD and PVR grade

INTRODUCTION

The full extent of IL-6 involvement in PVR pathophysiology has not yet been comprehensively investigated. The aim of this study was the comparison of the IL-6 effect on MMP expression between SRF and the vitreous in the context of RRD complicated by PVR.

MATERIALS AND METHODS

Thirty-one SRF samples from 31 eyes of 31 consecutive patients suffering from RRD with PVR were collected during treatment by scleral buckling. Twenty-eight vitreous samples from 28 eyes of 28 RRD patients with PVR were collected during surgical management with pars plana vitrectomy (PPV). Enzyme Linked Immunosorbent Assay was employed for the measurement of MMP-1, -3, -8 and TIMP-1 concentrations (in ng/ml). MMP gelatinolytic activity was determined with the use of gelatin zymography analysis using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE).

RESULTS

Correlation analysis in the SRF revealed a significant correlation between MMP-1/IL6 and RRD duration. Regression analysis in the SRF revealed a significant correlation between the MMP-9/IL-6 and RRD extent. In the same fluid, with respect to PVR grade, ANOVA revealed a significant relationship with the proMMP-2/IL-6, MMP-2/IL6 and TIMP-1/IL-6 ratios. Graphical representation of the results revealed that, between the SRF and vitreous groups, significant peak values were observed for all MMP/IL-6 and TIMP-1/IL-6 ratios included in this study with the exception of the MMP-2/IL-6 ratio.

CONCLUSIONS

It appears that there is a significant correlation between the presence of IL-6 and MMP/TIMP ratio in the SRF, indicating that IL-6 may contribute to the increased MMP/TIMP ratio during PVR.

Diabetic retinopathy treated with laser photocoagulation and the indirect effect on glycaemic control

PURPOSE

To identify any possible relation between glycaemic control and previous laser photocoagulation for diabetic retinopathy.

METHODS

Seventy-two patients with diabetes were included in the study and were separated into 2 groups according to previous treatment (group A) or not (group B) with argon laser photocoagulation. Glycaemic control was estimated by measuring blood levels of HbA1c in four consecutive measurements.

RESULTS

Blood levels of HbA1c in group A were significantly lower 3, 6, and 12 months after laser treatment as compared to blood levels of HbA1c before laser treatment (7.1 ± 0.4% versus 7.6 ± 0.9%, 7.2 ± 0.2% versus 7.6 ± 0.9%, and 7.1 ± 0.2% versus 7.6 ± 0.9%, resp., all P < 0.05). Blood levels of HbA1c in group B did not differ significantly in four consecutive measurements.

CONCLUSION

Our results suggest that we should anticipate a better glycaemic control in cases of patients with diabetes previously treated with laser photocoagulation.

Infrared irradiation alters the expression of matrix metalloproteinases and glycosaminoglycans in the cornea and crystalline lens

BACKGROUND

Prolonged exposure to infrared (IR) radiation is associated with different types of damage to cornea and lens. The aim of our study was to investigate the effect of acute and chronic exposure to IR radiation on the activity of matrix metalloproteinase-2 (MMP-2) and MMP-9 and on the expression of glycosaminoglycans (GAG) in the rabbit cornea and crystalline lens.

METHODS

New Zealand rabbits were subjected to IR radiation for 4 months (chronic exposure to IR) or to normal light (control group). In experiments regarding acute exposure, animals were subjected to IR radiation or normal light for 12 h, in the presence of 0.1% diclofenac sodium (eye drops instilled in the right eye of animals) or saline (instilled in the left eye of animals). The cornea and lens were dissected away and homogenized. The activity of MMP-2 and MMP-9 was assayed by gelatine zymography. Total GAG were isolated from tissue specimens after lipid extraction and extensive digestion with pronase and DNase and characterized by treatment with GAG-degrading enzymes, followed by electrophoresis on cellulose acetate membranes.

RESULTS

Acute or chronic exposure to IR radiation induced the activity of MMP-2 in cornea and lens, whereas only acute IR radiation increased the content of heparan sulphate in crystalline lens. Local administration of diclofenac sodium did not prevent the above effects of acute IR radiation.

CONCLUSIONS

The detrimental effects of excessive or prolonged exposure of the eyes to IR radiation are associated with induced activity of MMP-2 in cornea and lens and alterations in the content of heparan sulphate in lens. Thus, MMP and GAG may offer alternative targets for pharmacological intervention to confront ocular damages associated with IR radiation.

Pelvic schwannoma in the right parametrium

Neurilemomas are benign usually encapsulated nerve sheath tumors derived from the Schwann cells. These tumors commonly arise from the cranial nerves as acoustic neurinomas but they are extremely rare in the pelvis and the retroperitoneal area (less than 0.5% of reported cases), unless they are combined with von Recklinghausen disease (type 1 neurofibromatosis). We report the case of a 58-year-old female with pelvic schwannoma, 6.5 × 5.5 cm in size, in the right parametrium. This is the first case reported in the literature. Based on the rarity of this tumor and in order to ensure optimum treatment and survival for our patient, we performed laparotomy with total abdominal hysterectomy and en-block tumor excision. A frozen section was taken during the surgery before complete resection of the mass, which was ambiguous. Because of the possibility of malignancy, complete excision of the mass was performed, with pelvic blunt dissection. Histological examination showed a benign neoplasm, originating from the cells of peripheral nerve sheaths; diagnosis was a schwannoma. There were degenerative areas, including cystic degeneration, hemorrhagic infiltrations, ischemic foci with pycnotic cells, and collagen replacement. Pelvic schwannomas are rare neoplasms that can be misdiagnosed. Laparoscopy is a safe and efficient option for approaching benign pelvic tumors and might offer the advantage of better visualization of structures due to the magnification in laparoscopic view, especially in narrow anatomic spaces.

Alterations in serum MMP and TIMP concentrations following chronic heroin abuse

Abstract Context: Although opiate abuse is known to affect matrix metalloproteinases (MMPs), data on these enzymes and their tissue inhibitors in heroin addicts are scarce.

OBJECTIVE

In the present study, we determined serum concentrations of MMP-2, MMP-9, tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 in heroin users, and compared them with healthy individuals. We evaluated whether 21 d of abstinence are adequate to reverse the effect of opiates and we compared seropositive with seronegative, for anti-HCV antibodies, heroin users.

MATERIALS AND METHODS

Twenty-six heroin-dependent male volunteers and an equal number of healthy individuals participated in this study. ELISA was used to assess the serum levels of MMP-2, MMP-9, TIMP-1 and TIMP-2. Heroin users were assessed both upon admission and upon completion of a 21-d detoxification program.

RESULTS

Serum TIMP-1 concentrations were significantly lower and the ratios MMP-2/TIMP-1, MMP-9/TIMP-1 and MMP-2/TIMP-2 were significantly higher in heroin users compared to healthy individuals. Heroin users who were seropositive had lower MMP concentrations, as well as lower MMP/TIMP ratios, compared to those who were seronegative.

DISCUSSION

Our results showed that in heroin-addicted individuals, and especially those who are positive for anti-HCV antibodies, the balance between MMPs and TIMPs in serum is disrupted and this disruption cannot be restored within 21 d of abstinence.

CONCLUSION

Chronic heroin abuse disrupts the balance between MMPs and TIMPs in serum and this effect is not reversible within 21 d of abstinence.

Steroids and β2-agonists regulate hyaluronan metabolism in asthmatic airway smooth muscle cells

Glycosaminoglycans (GAGs), especially hyaluronic acid (HA), regulate tissue flexibility, cell motility, and inflammation. Airway smooth muscle cells (ASMCs) of patients with asthma exhibit abnormal HA metabolism, which contributes to inflammation and remodeling. Here, we investigated the effects of glucocorticoids and long-acting β(2)-agonists (LABAs) on GAG synthesis and HA metabolism by human primary ASMCs. ASMCs were isolated from airway specimens of 10 patients without asthma and 11 patients with asthma. ASMCs were incubated with glucocorticoids, LABAs, or their combination, as well as with their specific receptor antagonists. Secreted and deposited total GAGs were measured by [(3)H]-glucosamine incorporation. The expression of specific GAGs was determined by ELISA and electrophoresis. The expression of HA synthases (HAS), of hyaluronidases (HYALs), and of the HA receptor CD44 was determined by RT-PCR, immunoblotting in cell cultures, and immunohistochemistry in tissue sections of asthmatic lungs. In serum-activated asthmatic ASMCs, glucocorticoids and LABAs significantly inhibited the increased secretion and deposition of total GAGs, but they stimulated secreted and deposited HA of high molecular mass. This effect was attributed to increased mRNA and protein expression of HAS-1 and to the reduced expression of HYAL-1. Furthermore, drug treatment stimulated the expression of CD44 receptors in asthmatic ASMCs. These effects of the drugs were eliminated by their respective receptor inhibitors. Our findings indicate that the combination of glucocorticoids with LABAs counteracts the pathologic degradation of HA, and thereby may reduce the proinflammatory potential of asthmatic ASMCs.

Hyaluronic acid: A key molecule in skin aging

SKIN AGING IS A MULTIFACTORIAL PROCESS CONSISTING OF TWO DISTINCT AND INDEPENDENT MECHANISMS: intrinsic and extrinsic aging. Youthful skin retains its turgor, resilience and pliability, among others, due to its high content of water. Daily external injury, in addition to the normal process of aging, causes loss of moisture. The key molecule involved in skin moisture is hyaluronic acid (HA) that has unique capacity in retaining water. There are multiple sites for the control of HA synthesis, deposition, cell and protein association and degradation, reflecting the complexity of HA metabolism. The enzymes that synthesize or catabolize HA and HA receptors responsible for many of the functions of HA are all multigene families with distinct patterns of tissue expression. Understanding the metabolism of HA in the different layers of the skin and the interactions of HA with other skin components will facilitate the ability to modulate skin moisture in a rational manner.

Elevated circulating levels of the serum acute-phase protein YKL-40 (chitinase 3-like protein 1) are a marker of obesity and insulin resistance in prepubertal children

YKL-40 (chitinase 3-like protein 1) is a newly recognized protein that is secreted by activated macrophages and neutrophils and expressed in a broad spectrum of inflammatory conditions and cancers. It has also been associated with endothelial dysfunction and diabetes in adults. Its role in childhood obesity has not been evaluated yet. Our aim was to evaluate the associations of serum YKL-40 levels with markers of obesity, inflammation, and insulin resistance in children. Forty-one obese prepubertal children and 41 age- and sex-matched lean controls were included, and serum YKL-40 levels were determined. Body mass index (BMI), blood pressure (BP), body fat percentage, fasting glucose, insulin, homeostasis model assessment for insulin resistance (HOMA-IR) index, whole-body insulin sensitivity index, lipids, white blood cell (WBC) count, C-reactive protein, and fibrinogen levels were also assessed. Obese children had higher YKL-40 levels compared with controls (P = .003). Insulin-resistant individuals showed higher YKL-40 compared with non-insulin-resistant individuals after adjusting for age and BMI (adjusted P = .039). Serum YKL-40 levels were positively correlated with age, BMI, body fat percentage, fasting glucose and insulin, HOMA-IR index, whole-body insulin sensitivity index, systolic BP, mean BP, and WBC count (P < .05). After adjustment for age, sex, BMI, WBC count, and systolic BP, HOMA-IR index remained significantly associated with YKL-40 levels (P < .001). The study suggests that YKL-40 levels are elevated in obese youth and represent a marker of insulin resistance even in childhood. Prospective studies are needed to determine whether children with elevated YKL-40 levels are at higher risk for future cardiovascular disease.

Clinicopathological characteristics of adnexal lesions diagnosed during pregnancy or cesarean section

OBJECTIVE

The diagnosis of an incidental adnexal lesion during pregnancy has become more common after the widespread use of routine ultrasonography (US). The aim of this study was to examine the diagnostic approach, management strategy and the pathological findings in cases of adnexal lesions that were diagnosed and treated during pregnancy in our department.

MATERIALS AND METHODS

This was a 15-year retrospective study. Cases of adnexal lesions detected during routine prenatal care by US or while performing cesarean section, between January 1996 and December 2010 at Aretaieion Hospital of the National University of Athens, were analyzed.

RESULTS

In this study period 39 cases of adnexal lesions were diagnosed during pregnancy or cesarean section. The age of the women was between 21 and 40 years (mean age 32.4). Surgical excision of the lesions was decided in 32 cases and conservative treatment was followed in the remaining seven cases. Surgical removal of the lesions was performed during cesarean section in 13 cases of term gestations and in four cases of preterm gestations in which pregnancy termination was considered necessary. Laparotomy during the antepartum period led to excision of adnexal lesions in 15 cases. Histology revealed benign ovarian lesions in 25 cases (78.1%), borderline ovarian tumors in two cases (6.3%), malignant ovarian tumors in four cases (12.5%) and adenocarcinoma of the appendix in one case (3.1%) presenting as an ovarian mass.

DISCUSSION

The management of cases diagnosed with adnexal lesions during pregnancy remains controversial. According to the literature, the estimated risk of malignancy for adnexal masses during pregnancy is low (2-3%) and complications of these lesions are extremely rare. These data suggest that adnexal masses could be managed conservatively if possible with US follow-up. On the other hand, the results of this study showed a higher incidence of malignancy among adnexal lesions that were surgically treated (15.6%).

CONCLUSION

Surgical intervention and histological examination in cases suspicious for malignancy at US and clinical findings remain the treatment of choice even during pregnancy.

A rare case of intrinsic ureteral endometriosis causing hydronephrosis in a 40-year-old woman. A case report and literature review

Endometriosis is a multifactorial disease with unclear pathogenesis. Urinary tract endometriosis occurs in about 1% of all endometriotic lesions while isolated ureteral endometriosis is extremely rare. We present a case of intrinsic ureteral endometriosis causing ureteral stenosis in a 40-year's old woman, in combination with intestinal, extensive peritoneal and ovarian endometriosis. The clinicopathological features and investigation methods used, as well as the treatment approach are discussed. An individual therapy plan depending mainly on the patient's age, desire for children and the extent of the endometriotic foci should always be attempted. Collaboration between gynecologists and urologists was essential in our cases.

Epidermoid or dermoid cysts of the ovary? Clinicopathological characteristics of 28 cases and a new pathologic classification of an old entity

OBJECTIVE

The aim of this study was to present the clinical and pathological findings that aid in the differential diagnosis between epidermoid and dermoid ovarian tumors.

MATERIALS AND METHODS

This was a 15-year retrospective clinico-pathological study. A total of 28 cases of epidermoid ovarian cysts histologically confirmed after pathological examination at the Pathology Laboratory of Aretaieion University Hospital between January 1996 and December 2010, were analyzed and a literature review was performed.

RESULTS

Patients with epidermoid cysts presented with a main complaint of either abdominal pain or a palpable abdominal mass. In the 28 cases studied, 18 patients underwent cystectomy and four cases underwent oophorectomy. In six cases of post-menopausal women, abdominal hysterectomy with bilateral salpingo-oophorectomy was performed. No recurrent disease in the pelvis was reported during the available follow-up period which was from 12 to 30 months.

DISCUSSION

Epithelial epidermoid ovarian tumors represent less than one percent of ovarian surface epithelial tumors. The differential diagnosis of epidermoid cysts includes dermoid (mature cystic teratomas) tumors of the ovary. However, it should be mentioned that up to 17% of teratomas may include epidermoid tumors. In comparison to dermoid cysts which present at an earlier age but with a greater size, ovarian epidermoid tumors present as small- to medium-sized cystic lesions occurring at a significantly older age. The treatment of choice is conservative surgical therapy.

Differential expression of matrix metalloproteinases in the serum of patients with mucopolysaccharidoses

Mucopolysaccharidoses (MPS) represent a heterogeneous group of hereditary disorders, characterized by accumulation of glycosaminoglycans within the lysosomes. The objective of this study was to elucidate the expression and activity of matrix metalloproteinases (MMPs) in the serum of pediatric patients with MPS. Serum gelatinase activity was assessed by gelatin zymography and the concentration of circulating MMP-2, MMP-9, and of tissue inhibitors of MMPs (TIMP)-1 and TIMP-2 was measured by ELISA in the serum of seven patients with MPS (five with MPS III, 1 with MPS II and 1 with MPS VI), and healthy age- and sex-matched participants. Serum activity and protein levels of MMP-9 were significantly reduced whereas of MMP-2 were significantly increased in patients with MPS III, as compared to controls. There were no significant alterations in serum protein levels of TIMP-1 and TIMP-2 in patients with MPS III, as compared to controls. In MPS II, proMMP-2 activity and protein levels of MMP-2 were significantly increased, as compared to control. In MPS VI, enzyme replacement therapy reduced the activity and protein levels of MMP-9 up to 4 months after the initiation of treatment. The reported alterations in the expression of MMPs in the serum of patients with MPS suggest that these molecules may be used as potential biomarkers for the diagnosis, follow-up and response to therapy in patients with MPS.

Correlation of matrix metalloproteinase levels with the grade of proliferative vitreoretinopathy in the subretinal fluid and vitreous during rhegmatogenous retinal detachment

PURPOSE

We investigated the activity of matrix metalloproteinase (MMP)-2 and -9 and their latent pro-forms (proMMP-2, -9), and protein levels of MMP-1, -3, -8 and tissue inhibitor of MMPs (TIMP)-1 in the subretinal fluid (SRF) and vitreous of patients with rhegmatogenous retinal detachment (RRD). Potential correlations with proliferative vitreoretinopathy (PVR) grade were determined.

METHODS

Thirty-seven SRF and 32 vitreous samples from RRD patients and nine vitreous samples from human organ donors (controls), were collected and assayed for MMP-1, -3, -8/TIMP-1 levels using enzyme-linked immunosorbent assay (ELISA), and for proMMP-2, -9, MMP-2, -9 activity employing gelatine zymography.

RESULTS

ProMMP-2, -9, MMP-1, -3, -9, TIMP-1 were significantly higher in the SRF and vitreous of RRD patients compared to the vitreous of organ donors. MMP-8 levels were higher in RRD patients' SRF. Regarding PVR grade, MMPs and TIMP-1 were differentially present in SRF and vitreous. PVR grade correlated significantly with the levels of MMP-2 in SRF, while proMMP-2, MMP-1, -2, -3, -8, -9 and TIMP-1 levels correlated with PVR grade in the vitreous.

CONCLUSION

MMP/TIMP-1 levels are elevated in SRF and vitreous during RRD. Significant correlations between PVR grade and MMP-2 in SRF and proMMP-2, MMP-1, -2, -3, -8, -9 and TIMP-1 levels in vitreous were revealed. Investigation of MMP activity in vitreous may provide more valid conclusions compared to SRF pertaining to the role of the MMPs during RRD. The observations of the present study suggest a possible role for MMPs and TIMP-1 in PVR pathophysiology.

Vitreous and serum levels of vascular endothelial growth factor and platelet-derived growth factor and their correlation in patients with non-proliferative diabetic retinopathy and clinically significant macula oedema

PURPOSE

To investigate possible correlations between vitreous and/or serum levels of platelet-derived growth factor isoforms (PDGF-AA, -AB and -BB) with parameters associated with non-proliferative diabetic retinopathy (NPDR) and clinically significant macula oedema (CSMO); to compare the results to relevant results regarding vascular endothelial growth factor (VEGF), which is an established growth factor affecting NPDR.

METHODS

Fifteen patients with NPDR, 31 patients with proliferative diabetic retinopathy (PDR) and 15 non-diabetic patients were included in the study. Vitreous and serum samples were obtained during vitrectomy. PDGF-AA, -AB and -BB, as well as VEGF, were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

PDGF-AA, -AB and -BB and VEGF were all expressed in the serum and vitreous of controls and patients with NPDR. The levels of PDGF-AA, PDGF-AB and VEGF in vitreous were significantly increased in the NPDR group compared to controls, while PDGF-BB levels were significantly decreased in the NPDR group compared to controls. The levels of all PDGF isoforms and VEGF in vitreous were significantly increased in the PDR group compared to the NPDR group. No such differences were evident in serum. PDGF-AA and VEGF correlated significantly to the severity of NPDR. PDGF or VEGF in vitreous of NPDR patients did not correlate with retinal photocoagulation (RP) or the serum levels of haemoglobin A1c (HbA1c). There was no correlation between the vitreous and serum levels of VEGF or PDGF in patients with PDR. Only PDGF-AB vitreous levels correlated significantly with PDGF-BB vitreous levels in the NPDR group.

CONCLUSION

It appears that in addition to VEGF, almost all PDGF isoforms in the vitreous are also correlated with NPDR and CSMO.

Interleukin-6 and the matrix metalloproteinase response in the vitreous during proliferative vitreoretinopathy

PURPOSE

To investigate the levels of IL-6 in the vitreous of patients with RRD complicated with PVR and correlate the IL-6 levels with matrix metalloproteinase (MMP)-1,-2,-3,-8,-9 and tissue inhibitor of metalloproteinases (TIMP)-1 with respect to RRD extent, duration and PVR grade.

DESIGN

Cohort study.

PARTICIPANTS

Twenty-eight vitreous samples from 28 eyes of 28 patients with RRD complicated with PVR.

METHODS

Institutional study. Twenty-eight vitreous samples from 28 eyes of 28 patients with RRD complicated with PVR were collected during pars plana vitrectomy (PPV) and were compared to vitreous control samples. IL-6, MMP-1,-3,-8 and TIMP-1 levels were measured using ELISA while enzymatic activity of MMP-2, and -9 was determined employing gelatin zymography.

RESULTS

Protein IL-6 (p=0.030), MMP-1 (p=0.003), MMP-3 (p=0.003), TIMP-1 (p=0.001) levels as well as enzymatic activity of proMMP-9 (p=0.013), MMP-9 (p=0.017) and proMMP-2 (p=0.010), were significantly increased in PVR patients as compared to controls. IL-6 levels correlated with MMP-1 (p=0.002), proMMP-2 (p=0.006), MMP-3 (p=0.001) and TIMP-1 (p=0.006). Regression analysis revealed positive correlations between IL-6 and all MMPs and TIMP-1.

CONCLUSIONS

Taking into account the previously established effect of interleukins in MMP activity, the findings of this study suggest a role of IL-6 in MMP stimulation during PVR development.

Differential expression of matrix metalloproteinases and proteoglycans in Juvenile Hyaline Fibromatosis

BACKGROUND

Juvenile Hyaline Fibromatosis (JHF) is a rare autosomal recessive disorder, histologically characterized by the production and deposition of an unidentified hyaline material in the skin and other organs. Extracellular matrix molecules are implicated in the development of skin lesion which is debilitating and recurrent and, so far, no treatment is satisfactory.

OBJECTIVE

To investigate the expression of matrix metalloproteinases (MMPs), their tissue inhibitors (TIMPs) and proteoglycans in lesional as compared to site-matched lesion-free skin tissue specimens of a JHF patient, aiming to elucidate the aetiopathological mechanisms involved in the development of JHF skin lesions.

METHODS

Gelatinase activity of MMP-2 and MMP-9 was investigated by gelatine zymography. Protein levels of MMP-2, MMP-9, TIMP-1 and TIMP-2 in skin tissue extracts were measured by ELISA. Gene expression of MMPs, TIMPs and proteoglycans was examined by quantitative RT-PCR.

RESULTS

JHF lesions exhibited significantly higher activity as well as elevated protein and gene expression of MMP-2 and MMP-9, as compared to lesion-free skin tissue specimens. Decorin was downregulated and aggrecan was upregulated in lesional skin, as compared to normal skin.

CONCLUSION

The results presented in this study indicate that MMPs and proteoglycans may be involved in the pathogenesis of JHF and therefore these molecules may offer alternative targets for pharmacological intervention to achieve more radical and effective treatment.

Virilizing ovarian Krukenberg tumor in a 27-year-old pregnant woman. A case report and literature review

A case is reported of a 27-year-old pregnant woman with ovarian tumors, measuring 12 cm and 11.5 cm in the greatest diameter, discovered during investigation for virilization symptoms. Termination of the pregnancy at the 22nd week of gestation and tumorectomy with both adnexa were performed, with the provisional diagnosis of arrhenoblastoma. Pathological examination of the tumors showed typical Krukenberg neoplasms and subsequent upper GI tract endoscopy revealed a gastric cancer that was excised. The pathological examination revealed a diffuse type gastric adenocarcinoma with signet ring morphology, similar to ovarian tumors. In any case of ovarian tumor with unusual hormonal manifestations, in addition to hormonally active sex cord-stromal neoplasms, metastatic ovarian tumors must be considered as well, especially in cases of bilateral tumors.

Extraovarian mature cystic teratoma of the mesentery. A case report and literature review

A case is reported of a 60-year old woman who had intermittent abdominal pain due to a mesenteric teratoma which was misdiagnosed by the standard methods of abdominal tumor diagnosis as an ovarian tumor. The neoplasm measured 9 x 8 x 8 cm, was filled by hair and sebum, and histologically presented the typical features of a mature cystic teratoma. The mesentery and overlying small intestine showed an extensive inflammatory granulomatous reaction. The uterus and adnexa were free of neoplasmatic disease. This case of extra ovarian mature cystic teratoma which developed in the mesentery is unique among > 2000 ovarian tumors examined during a 30-year period at Aretaieion Hospital Pathology Laboratory.

Nodular basal cell carcinoma is associated with increased hyaluronan homeostasis

BACKGROUND

Basal cell carcinoma (BCC) is one of the most frequent forms of malignancy in humans. Although BCC is a tumour of low degree of malignancy, if left untreated, it can be locally aggressive, eat away at tissues and cause ulceration. Nodular is the most common subtype of BCC (>50%). Although apparently non-invasive, micronodular, a certain subgroup of nodular, is likely to recur. Glycosaminoglycans (GAGs), such as hyaluronic acid (HA), are extracellular matrix molecules of high importance in malignant transformation, metastasis and other complex remodelling processes.

OBJECTIVES

To investigate the expression of GAGs and their metabolizing enzymes in nodular BCC, when compared with adjacent healthy human skin tissue specimens.

METHODS

Total GAGs were isolated and purified from nodular BCC and normal adjacent human skin tissue specimens. GAGs were subsequently fractionated by electrophoresis on cellulose acetate membranes and characterized using specific GAG-degrading enzymes. The content of HA in total GAGs was measured using ELISA and the expression of HA synthases (HAS), hyaluronidases (HYAL) and HA receptors (CD44 and receptor hyaluronic acid-mediated motility (RHAMM) was assessed using RT-PCR.

RESULTS

Nodular BCC is associated with increased levels of HA concomitant with upregulation of gene expression of HAS3, HYAL3 and RHAMM, when compared with normal adjacent skin.

CONCLUSION

These results indicate that HA homeostasis in nodular BCC shows distinct features which may be helpful in understanding the complex behaviour of nodular subtype of BCC, thus eventually leading to new treatment strategies.

Angiogenic growth factors and their inhibitors in diabetic retinopathy

Diabetic retinopathy is considered one of the vision-threatening diseases among working-age population. The pathogenesis of the disease is regarded multifactorial and complex: capillary basement membrane thickening, loss of pericytes, microaneuryms, loss of endothelial cells, blood retinal barrier breakdown and other anatomic lesions might contribute to macular edema and/or neovascularization the two major and sight threatening complications of diabetic retinopathy. A number of proangiogenic, angiogenic and antiangiogenic factors are involved in the pathogenesis and progression of diabetic retinal disease, Vascular Endothelial Growth Factor (VEGF) being one of the most important. Other growth factors, which are known to participate in the pathogenesis of the disease, are: Platelet Derived Growth Factor (PDGF), Fibroblast Growth Factor (FGF), Hepatocyte Growth Factor (HGF), Transforming Growth Factor (TGF), Placental Endothelial Cell Growth Factor (PlGF), Connective Tissue Growth Factor (CTGF). Other molecules that are involved in the disease mechanisms are: intergrins, angiopoietins, protein kinase C (PKC), ephrins, interleukins, leptin, angiotensin, monocyte chemotactic protein (MCP), vascular cell adhesion molecule (VCAM), tissue plasminogen activator (TPA), and extracellular matrix metalloproteinases (ECM-MMPs). However, the intraocular concentration of angiogenic factors is counterbalanced by the ocular synthesis of several antioangiogenic factors such as pigment epithelial derived factor (PEDF), angiostatin, endostatin, thrombospondin, steroids, atrial natriuretic peptide (ANP), inteferon, aptamer, monoclonal antibodies, VEGF receptor blocker, VEGF gene suppressors, intracellular signal transduction inhibitors, and extracellular matrix antagonists. Growth stimulation or inhibition by these factors depends on the state of development and differentiation of the target tissue. The mechanisms of angiogenesis factor action are very different and most factors are multipotential; they stimulate proliferation or differentiation of endothelial cells. This review attempts to briefly outline the knowledge about peptide growth factor involvement in diabetic retinopathy. Further ongoing research may provide better understanding of molecular mechanisms, disease pathogenesis and therapeutic interactions.

Extrinsic ageing in the human skin is associated with alterations in the expression of hyaluronic acid and its metabolizing enzymes

Extrinsic skin ageing or 'photoageing', as opposed to intrinsic skin ageing, is the result of exposure to external factors, mainly ultraviolet irradiation. Glycosaminoglycans (GAG) and particularly hyaluronic acid (HA) are major components of the cutaneous extracellular matrix involved in tissue repair. However, their involvement in extrinsic skin ageing remains elusive. In this study, we investigated the expression of HA and its metabolizing enzymes in photoexposed and photoprotected human skin tissue specimens, obtained from the same patient. Total GAG were isolated, characterized using specific GAG-degrading enzymes and separated by electrophoresis on cellulose acetate membranes and polyacrylamide gels. Quantitation of HA in total GAG was performed using ELISA. Gene expression of hyaluronan synthases (HAS), hyaluronidases (HYAL) and HA receptors CD44 and receptor for HA-mediated motility (RHAMM) was assessed by RT-PCR. We detected a significant increase in the expression of HA, of lower molecular mass, in photoexposed skin as compared with photoprotected skin. This increase was associated with a significant decrease in the expression of HAS1 and an increase in the expression of HYAL1-3. Furthermore, the expression of HA receptors CD44 and RHAMM was significantly downregulated in photoexposed as compared with photoprotected skin. These findings indicate that extrinsic skin ageing is characterized by distinct homoeostasis of HA. The elucidation of the role of HA homoeostasis in extrinsic skin ageing may offer an additional approach in handling cutaneous ageing.

A high-protein low-fat diet is more effective in improving blood pressure and triglycerides in calorie-restricted obese individuals with newly diagnosed type 2 diabetes

BACKGROUND/OBJECTIVES

There is controversy over dietary protein's effects on cardiovascular disease risk factors in diabetic subjects. It is unclear whether observed effects are due to increased protein or reduced carbohydrate content of the consumed diets. The aim of this study was to compare the effects of two diets differing in protein to fat ratios on cardiovascular disease risk factors.

SUBJECTS/METHODS

A total of 17 obese (body mass index (BMI) ranging from 31 to 45 kg/m(2)) volunteers with type 2 diabetes (DM2), aged 46+/-3 years, consumed two diets, each for 4 weeks, with 3 weeks of washout period in a random, blind, crossover design. The diets were: (1) a high-protein low-fat diet (HP-LF, with 30% protein, 50% carbohydrates and 20% fat) and (2) a low-protein high-fat diet (LP-HF, with 15% protein, 50% carbohydrates and 35% fat). Their effects on fasting glycemic control, lipid levels and blood pressure, and on postprandial glucose and insulin responses after a standard test meal at the beginning and end of each dietary intervention were analyzed.

RESULTS

Both diets were equally effective in promoting weight loss and fat loss and in improving fasting glycemic control, total cholesterol and low-density lipoprotein (LDL) cholesterol, but the HP-LF diet decreased to a greater extent triglyceride (TG) levels (P=0.04) when compared with the LP-HF diet. HP-LF diet improved significantly both systolic and diastolic blood pressure when compared with the LP-HF diet (P<0.001 and P<0.001, respectively). No differences were observed in postprandial glucose and insulin responses.

CONCLUSIONS

A protein to fat ratio of 1.5 in diets significantly improves blood pressure and TG concentrations in obese individuals with DM2.

A high protein low fat meal does not influence glucose and insulin responses in obese individuals with or without type 2 diabetes

BACKGROUND

When substituted for carbohydrate in a meal, dietary protein enhances glycaemic control in subjects with type 2 diabetes (DM2). It is unknown whether the effect is a result of increased protein or reduced carbohydrate. The present study aimed to compare the effects of two meals differing in protein to fat ratios on post-prandial glucose and insulin responses.

METHODS

This was a crossover, blind study in which obese subjects with (n = 23) and without (n = 26) DM2 consumed two meals in random order with equal amounts of energy (3.1 MJ, 741 kcal), fibre and carbohydrates and a 1-week washout period. Meals were a high protein, low fat (30% protein, 51% carbohydrates, 19% fat) meal and a low protein, high fat (15% protein, 51% carbohydrates, 34% fat) meal. Subjects were matched for age and body mass index. Plasma glucose and insulin were measured at fasting, 30, 60, 90, 120 min post-prandially. Insulin resistance and insulin sensitivity were assessed.

RESULTS

There was no significant meal effect on glucose and insulin responses within groups. Glucose response was higher in diabetic (120 min 11 +/- 0.7 mmol L(-1)) compared to nondiabetic (120 min 5 +/- 0.2; P < 0.001) subjects. Diabetic subjects had significantly higher insulin resistance (P < 0.001) and lower insulin sensitivity (P < 0.001) than nondiabetics. Although peak insulin levels, 60 min post-prandially, did not differ between groups (81 +/- 9 pmol L(-1) for diabetic versus 79 +/- 7 pmol L(-1) for nondiabetic subjects), they were achieved much later, 90 min post-prandially, in diabetic, (99 +/- 8 pmol L(-1)) compared to nondiabetic (63 +/- 7 pmol L(-1), P = 0.002) subjects.

CONCLUSIONS

Manipulating protein to fat ratio in meals does not affect post-prandial plasma blood glucose or insulin responses in obese people with and without DM2.

Enhanced deposition of low-molecular-weight hyaluronan in lungs of cigarette smoke-exposed mice

Chronic obstructive pulmonary disease (COPD) is characterized by infiltration of inflammatory cells, destruction of lung parenchyma, and airway wall remodeling. Hyaluronan (HA) is a component of the extracellular matrix, and low-molecular-weight (LMW) HA fragments have proinflammatory capacities. We evaluated the presence of HA in alveolar and airway walls of C57BL/6 mice that were exposed to air or cigarette smoke (CS) for 4 weeks (subacute) or 24 weeks (chronic). We measured deposition of the extracellular matrix proteins collagen and fibronectin in airway walls and determined the molecular weight of HA purified from lung tissue. In addition, we studied the expression of HA-modulating genes by RT-PCR. HA staining in alveolar walls was significantly enhanced upon chronic CS exposure, whereas HA levels in the airway walls were already significantly higher upon subacute CS exposure and remained elevated upon chronic CS exposure. This differed from the deposition of collagen and fibronectin, which are only elevated at the chronic time point. In lungs of CS-exposed mice, the molecular weight of HA clearly shifted toward more LMW HA fragments. CS exposure significantly increased the mRNA expression of the HA synthase gene Has3 in total lung tissue, whereas the expression of Has1 was decreased. These in vivo studies in an experimental model of COPD show that CS exposure leads to enhanced deposition of (mostly LMW) HA in alveolar and bronchial walls by altering the expression of HA-modulating enzymes. This may contribute to airway wall remodeling and pulmonary inflammation in COPD.

Differential glycosaminoglycan expression and hyaluronan homeostasis in juvenile hyaline fibromatosis

BACKGROUND

Juvenile hyaline fibromatosis (JHF) is a rare autosomal recessive disease characterized histologically by deposition of hyaline material and clinically by multiple skin lesions. Clarification of the molecular and structural changes involved in JHF skin lesions may unravel targets for pharmacotherapy.

OBJECTIVE

We sought to investigate the expression of glycosaminoglycans and their metabolizing enzymes in lesional as compared with lesion-free skin tissue specimens in JHF.

METHODS

Glycosaminoglycans were isolated, purified, and fractionated by electrophoresis on cellulose acetate membranes and agarose gels. Hyaluronic acid (HA) was quantitated by enzyme-linked immunosorbent assay and the expression of HA metabolizing enzymes was investigated using reverse transcriptase-polypeptide chain reaction.

RESULTS

JHF lesions exhibited significantly less HA and elevated amounts of dermatan sulfate and chondroitin sulfate, whereas gene expression of HA synthase-1 and HA synthase-3 was significantly down-regulated, as compared with lesion-free skin tissue specimens.

LIMITATIONS

Because JHF is a rare disease, a limitation to our study was that we collected skin tissue specimens from only one patient.

CONCLUSION

The significant alterations of HA homeostasis in JHF lesions provide further understanding of JHF pathogenesis and may offer a target for pharmacologic intervention to treat the skin lesions associated with JHF.

The 'sweet' and 'bitter' involvement of glycosaminoglycans in lung diseases: pharmacotherapeutic relevance

The extracellular matrix (ECM) plays a significant role in the structure and function of the lung. The ECM is a three-dimensional fibre mesh, comprised of various interconnected and intercalated macromolecules, among which are the glycosaminoglycans (GAG). GAG are long, linear and highly charged, heterogeneous polysaccharides that are composed of a variable number of repeating disaccharide units (macromolecular sugars) and most of them, as their name implies, have a sweet taste. In the lung, GAG support the structure of the interstitium, the subepithelial tissue and the bronchial walls, and are secreted in the airway secretions. Besides maintaining lung tissue structure, GAG also play an important role in lung function as they regulate hydration and water homeostasis, modulate the inflammatory response and influence lung tissue repair and remodelling. However, depending on their size and/or degree of sulphation, and their immobilization or solubilization in the ECM, specific GAG in the lung either live up to their sweet taste/name, supporting normal lung physiology, or they are associated to 'bitter' effects, related to lung pathology. The present review discusses the biological role of GAG in the lung as well as the involvement of these molecules in various respiratory diseases. Given the great structural diversity of GAG, understanding the changes in GAG expression that occur in lung diseases may lead to novel targets for pharmacological intervention in order to prevent and/or to treat a range of lung diseases.

Vitreous and serum levels of platelet-derived growth factor and their correlation in patients with proliferative diabetic retinopathy

PURPOSE

We investigated possible correlations between vitreous and/or serum levels of platelet derived growth factor isoforms (PDGF-AA, -AB, -BB) with parameters associated with proliferative diabetic retinopathy (PDR), and compared the results to vascular endothelial growth factor (VEGF), which is an established growth factor affecting PDR.

METHODS

Thirty-one patients with PDR and 15 non-diabetic patients were included in the study. Vitreous and serum samples were obtained during vitrectomy. PDGF-AA, -AB, and -BB, as well as VEGF, were measured by enzyme-linked immunosorbent assay.

RESULTS

PDGF-AA, -AB, -BB, and VEGF were all expressed in serum and vitreous of controls and patients with PDR. The levels of all PDGF isoforms and VEGF in vitreous were significantly increased in the PDR group, as compared to controls. No such differences were evident in serum. PDGF-AA and PDGF-BB correlated significantly to the severity but not the activity of PDR. PDGF-AB and -BB were significantly lower in vitreous of patients with pre-performed complete panretinal photocoagulation (PRP) as compared to incomplete or without PRP. PDGF did not correlate significantly to fibrovascular tissue, on the disc or elsewhere, to long-standing vitreous hemorrhage, to tractional retinal detachment, or to posterior vitreous detachment. PDGF or VEGF in vitreous or serum of PDR patients did not correlate with the serum levels of HbA1C. There was no correlation between the vitreous and serum levels of VEGF or PDGF in patients with PDR.

CONCLUSIONS

It appears that, in addition to VEGF, PDGF-AA, -AB, and -BB in the vitreous are also correlated with PDR.

Decreased hyaluronan in airway smooth muscle cells from patients with asthma and COPD

Glycosaminoglycans (GAG) are essential extracellular matrix molecules which regulate tissue flexibility, a parameter that is reduced in airways of patients with asthma and chronic obstructive pulmonary disease (COPD). We investigated the expression of GAG and their metabolising enzymes in primary human airway smooth muscle cells (ASMC) obtained from healthy donors (controls) and patients with asthma or COPD. Total GAG synthesis was assessed by [(3)H]-glucosamine incorporation. GAG were isolated, purified, fractionated by electrophoresis and characterised using specific GAG-degrading enzymes. Secretion of hyaluronic acid (HA) by ASMC from patients with asthma or COPD was significantly decreased compared with controls. RT-PCR analysis and western blotting revealed that this decrease was associated with a significant reduction in the expression of HA synthase-1 and -2 and a significant increase of hyaluronidase-1. Furthermore, the expression of the HA receptor CD44 was significantly decreased, whereas the receptor for HA-mediated motility was not expressed in asthma or COPD. Our results indicate that there is a decreased expression of HA in asthma and COPD associated with a synergistic regulation of HA metabolising enzymes that may regulate the pathological airway remodelling in these lung diseases.

Increased hyaluronic acid content in idiopathic pulmonary arterial hypertension

Idiopathic pulmonary arterial hypertension (IPAH) is a fatal disease characterised by elevated blood pressure in the pulmonary circulation. Initial vasoconstriction, proliferation of pulmonary arterial smooth muscle cells (PASMC) and increased deposition of extracellular matrix (ECM) contribute to pathological remodelling of pulmonary arterioles in IPAH. Glycosaminoglycans (GAGs), components of the ECM, control cellular proliferation and differentiation, but their expression in IPAH remains elusive. In the present study, GAG expression was investigated in the lungs of patients with IPAH or control transplant donors, and expression and localisation of GAG-metabolising enzymes were analysed in vivo and in vitro. A significant increase in the expression of hyaluronic acid (HA) was detected in IPAH lungs, associated with increased hyaluronan synthase (Has)1 and decreased hyaluronoglucosaminidase 1 gene expression, as assessed by quantitative RT-PCR and Western blotting. HAS1 protein localised to PASMC in vivo and increased HA deposition was observed in remodelled pulmonary arteries in IPAH. Transforming growth factor-beta1, a profibrotic growth factor, led to increased HA secretion and HAS1 expression in primary PASMC. The results demonstrate an increased hyaluronic acid content in idiopathic pulmonary arterial hypertension lungs, associated with increased hyaluronan synthase 1 and decreased hyaluronoglucosaminidase 1 gene expression. Synergistic regulation of glycosaminoglycan-metabolising enzymes in favour of accumulation may, thus, regulate pathological vascular remodelling in idiopathic pulmonary arterial hypertension lungs.

Terazosin Modifies the Content of Glycosaminoglycans and the Activity of Matrix Metalloproteinase 2 in the Rat Ventral Prostate

OBJECTIVES

We have investigated the effects of terazosin on the content of glycosaminoglycans (GAGs), the activity of matrix metalloproteinase 2 (MMP-2) and MMP-9, and the content of tissue inhibitors of MMP (TIMP) in the ventral prostate of Wistar rats.

METHODS

Rats were treated with terazosin (0.12, 1.2mg/kg orally every second day) for 120 d. GAGs were isolated and purified from ventral prostate homogenates by lipid extraction, ethanol precipitation, and extensive digestion with pronase and DNAse, separated by electrophoresis, and characterised using specific enzymes. The activity of MMP-2 and MMP-9 was estimated using gelatin zymography and TIMP-1 and TIMP-2 were measured by enzyme-linked immunosorbent assay.

RESULTS

Terazosin treatment did not affect the weight of the ventral prostate gland. The prostate contains hyaluronic acid, chondroitin sulfate (CS), dermatan sulfate (DS), and heparan sulfate (HS), MMP-2, TIMP-1, and TIMP-2, but not MMP-9. Terazosin caused a significant increase in the relative content of DS and a significant decrease in the relative content of CS and to a lesser extent of HS. Terazosin evoked a significant increase in the activity of proMMP-2 and MMP-2 but did not affect TIMP.

CONCLUSIONS

The differential effect of terazosin treatment in GAG molecules of the rat prostate may be beneficial because CS is known to induce and DS to inhibit cell proliferation. The effect of terazosin on GAGs and MMP-2 may contribute in the molecular mechanisms of terazosin-induced apoptosis because HS and CS have a proapoptotic effect, whereas DS and MMP-2 are antiapoptotic.

Use of amifostine in the treatment of recurrent solid tumours in children

AIM

Preclinical and clinical evaluation of amifostine (AMI) administration in conjunction with systemic chemotherapy supports its role as a cytoprotective agent of normal tissues without loss of impairing the antitumour effectiveness of chemotherapeutic agents. Since only a limited number of clinical studies has been performed using AMI in paediatric pts with malignancies we investigated the protective effect of AMI against carboplatin-induced myelotoxicity and nephrotoxicity in a paediatric group of patients.

MATERIAL AND RESULTS

AMI was administered in 18/28 paediatric patients with reccurent solid tumours along with ICE (ifosfamide, carboplatin, etoposide) chemotherapy. A significant (p<0.05) decrease in GFR was observed in the control group whereas it was maintained at pre-treatment levels in the AMI-treated group. Leukopenia and neutropenia were significantly (p<0.05) less in AMI-group. No protective effect of AMI was shown concerning thrombocytopenia.

CONCLUSIONS

AMI was generally well tolerated at the dose of 740 mg/m2. Side effects including nausea, vomiting, hypotension, flushing and rigors were moderate and reversible and the interruption of infusion was never required.

Cell type-specific effect of hypoxia and platelet-derived growth factor-BB on extracellular matrix turnover and its consequences for lung remodeling

Hypoxia is associated with extracellular matrix remodeling in several inflammatory lung diseases, such as fibrosis, chronic obstructive pulmonary disease, and asthma. In a human cell culture model, we assessed whether extracellular matrix modification by hypoxia and platelet-derived growth factor (PDGF) involves the action of matrix metalloproteinases (MMPs) and thereby affects cell proliferation. Expression of MMP and its activity were assessed by zymography and enzyme-linked immunosorbent assay in human lung fibroblasts and pulmonary vascular smooth muscle cells (VSMCs), and synthesis of soluble collagen type I was assessed by enzyme-linked immunosorbent assay. In both cell types, hypoxia up-regulated the expression of MMP-1, -2, and -9 precursors without subsequent activation. MMP-13 was increased by hypoxia only in fibroblasts. PDGF-BB inhibited the synthesis and secretion of all hypoxia-dependent MMP via Erk1/2 mitogen-activated protein (MAP) kinase activation. Hypoxia and PDGF-BB induced synthesis of soluble collagen type I via Erk1/2 and p38 MAP kinase. Hypoxia-induced cell proliferation was blocked by antibodies to PDGF-BB or by inhibition of Erk1/2 but not by the inhibition of MMP or p38 MAP kinase in fibroblasts. In VSMCs, hypoxia-induced proliferation involved Erk1/2 and p38 MAP kinases and was further increased by fibroblast-conditioned medium or soluble collagen type I via Erk1/2. In conclusion, hypoxia controls tissue remodeling and proliferation in a cell type-specific manner. Furthermore, fibroblasts may affect proliferation of VSMC indirectly by inducing the synthesis of soluble collagen type I.

Expression of matrix metalloproteinases in the subretinal fluid correlates with the extent of rhegmatogenous retinal detachment

BACKGROUND

We investigated the activity of matrix metalloproteinase (MMP)-2 and -9 and the protein levels of MMP-1, -3, -8 and the tissue inhibitor of MMPs (TIMP)-1 in the subretinal fluid (SRF) of patients with rhegmatogenous retinal detachment (RRD) and establishment of potential correlations with clinical parameters.

METHODS

Thirty-seven SRF from RRD patients and nine vitreous samples from the human eye of organ donors (controls) were collected and assayed for MMP-1,-3,-8 and TIMP-1 levels using ELISA and for MMP-2 and -9 activity employing gelatin zymography.

RESULTS

MMP-1, MMP-3, MMP-8, proMMP-2, proMMP-9, MMP-9 and TIMP-1 levels were higher in SRF compared with vitreous fluid. Overall, MMPs and TIMPs were differentially expressed in SRF with respect to duration and extent of RRD, as well as to stage of proliferative vitreoretinopathy. Regression analysis for all data indicated that a model consisting of MMP-3, MMP-8 and proMMP-9 could estimate the extent of RRD.

CONCLUSIONS

MMPs and TIMP-1 levels are elevated in SRF during RRD. A regression model consisting of MMP-3, MMP-8 and proMMP-9 may be proved to be of potential use in providing information for evaluation of the extent of RRD.

Matrix metalloproteinases of epithelial origin in facial sebum of patients with acne and their regulation by isotretinoin

Acne vulgaris is a skin disorder of the sebaceous follicles, involving hyperkeratinization and perifollicular inflammation. Matrix metalloproteinases (MMP) have a predominant role in inflammatory matrix remodeling and hyperproliferative skin disorders. We investigated the expression of MMP and tissue inhibitors of MMP (TIMP) in facial sebum specimens from acne patients, before and after treatment with isotretinoin. Gelatin zymography and Western-blot analysis revealed that sebum contains proMMP-9, which was decreased following per os or topical treatment with isotretinoin and in parallel to the clinical improvement of acne. Sebum also contains MMP-1, MMP-13, TIMP-1, and TIMP-2, as assessed by ELISA and western blot, but only MMP-13 was decreased following treatment with isotretinoin. The origin of MMP and TIMP in sebum is attributed to keratinocytes and sebocytes, since we found that HaCaT keratinocytes in culture secrete proMMP-2, proMMP-9, MMP-1, MMP-13, TIMP-1, and TIMP-2. SZ95 sebocytes in culture secreted proMMP-2 and proMMP-9, which was also confirmed by microarray analysis. Isotretinoin inhibited the arachidonic acid-induced secretion and mRNA expression of proMMP-2 and -9 in both cell types and of MMP-13 in HaCaT keratinocytes. These data indicate that MMP and TIMP of epithelial origin may be involved in acne pathogenesis, and that isotretinoin-induced reduction in MMP-9 and -13 may contribute to the therapeutic effects of the agent in acne.

Expression of matrix metalloproteinases and their endogenous tissue inhibitors in skin lesions from patients with tuberous sclerosis

BACKGROUND

Tuberous sclerosis complex lesions of the skin may be disfiguring to patients and can only be treated by laser or cosmetic surgery. Clarification of the molecular and structural changes involved in skin hamartomas may unravel targets for pharmacotherapy.

OBJECTIVE

We investigated the expression of matrix metalloproteinase (MMP) and its tissue inhibitor (TIMP) in fibrous plaques, angiofibromas, and lesion-free skin specimens from patients with tuberous sclerosis complex.

METHODS

Gene expression of MMPs and TIMP-1 was measured by reverse transcription polymerase chain reaction, gelatinase activity by gelatin zymography, and the content of collagenases and TIMPs by enzyme-linked immunosorbent assay.

RESULTS

Compared with lesion-free specimens, hamartomas exhibited decreased levels of TIMPs and messenger RNA expression of TIMP-1, and increased content of MMP-1 and MMP-13 and activity of MMP-9, although gelatinase gene expression was diminished. Gene expression of MMP-15 and MMP-17 was not affected but was diminished for MMP-14.

CONCLUSION

The significant variations of the above extracellular matrix molecules between lesion-free specimens and tuberous sclerosis complex hamartomas overall favors a collagenous protein-degrading microenvironment in affected skin, and argue in support of antiprotease treatment for disfiguring skin lesions.

Hypoxia modulates the effects of transforming growth factor-beta isoforms on matrix-formation by primary human lung fibroblasts

Chronic hypoxia is implicated in lung fibrosis, which is characterized by enhanced deposition of extracellular matrix (ECM) molecules. Transforming growth factor-beta (TGF-beta) plays a key role in fibroblast homeostasis and is involved in disease states characterized by excessive fibrosis, such as pulmonary fibrosis. In this study, we investigated if hypoxia modulates the effects of TGF-beta on the expression of gelatinases: matrix metalloproteinase (MMP)-2 and MMP-9, interstitial collagenases: MMP-1 and MMP-13, tissue inhibitors of MMP (TIMP), collagen type I and interleukin-6 (IL-6). Primary human lung fibroblasts, established from tissue biopsies, were cultivated under normoxia or hypoxia in the presence of TGF-beta1, TGF-beta2 or TGF-beta3. Gelatinases were assessed by gelatin zymography and collagenases, TIMP, collagen type I and IL-6 by ELISA. Under normoxia fibroblasts secreted MMP-2, collagenases, TIMP, collagen type I and IL-6. TGF-betas significantly decreased MMP-1 and increased TIMP-1, IL-6 and collagen type I. Hypoxia significantly enhanced MMP-2, and collagenases. Compared to normoxia, the combination of TGF-beta and hypoxia reduced MMP-1, and further amplified the level of TIMP, IL-6, and collagen type I. Thus, in human lung fibroblasts hypoxia significantly increases the TGF-betas-induced secretion of collagen type I and may be associated to the accumulation of ECM observed in lung fibrosis.

Expression of proteoglycans and glycosaminoglycans in angiofibroma and fibrous plaque skin lesions from patients with tuberous sclerosis

Tuberous sclerosis complex (TSC) is a disorder of cell lineage, migration, proliferation and differentiation, characterized by the development of widespread benign hamartomas, which are particularly evident in hamartomatous lesions of the skin. The aim of this study was to investigate differences in gene expression of certain proteoglycans (PGs) and to characterize glycosaminoglycans (GAGs) in tissue specimens of normal skin, fibrous plaques and angiofibromas from patients with TSC. The expression of PG mRNA was determined by semiquantitative RT-PCR analysis. Total GAGs were isolated from tissue specimens after lipid extraction and extensive digestion with Pronase and DNase and characterized by treatment with GAG-degrading enzymes followed by electrophoresis on polyacrylamide gradient gels and cellulose acetate membranes. Normal skin specimens express versican, decorin and aggrecan and contain hyaluronic acid and dermatan sulphate. In angiofibroma specimens aggrecan is not expressed while versican splice variant with two EGF-like domains and decorin are downregulated. Furthermore, angiofibromas differ from normal skin in that they additionally contain keratan, heparan and chondroitin sulphates and do not contain dermatan sulphate. In fibrous plaque specimens gene expression of PGs was similar to that in normal skin, but with respect to GAGs, they contained a single acidic glycan population that did not share common structural features with known GAGs. The variations of the above ECM molecules between normal and TSC skin may be attributed to TSC-related mutations and, overall, support the TSC-associated pathological manifestations of cell migration, proliferation and differentiation.

Thrombotic risk factors and extent of liver fibrosis in chronic viral hepatitis

BACKGROUND AND AIMS

Thrombosis of the small intrahepatic veins has been suggested to trigger liver tissue remodelling. We evaluated the prevalence of multiple thrombotic risk factors and their association with the extent of fibrosis in chronic viral hepatitis.

METHODS

Ninety consecutive patients with chronic hepatitis B or C without malignancy, a history of venous thrombosis, or antiviral/immunosuppressive therapy within the last six months were included. Thrombophilic and coagulation factors were evaluated on the liver biopsy day.

RESULTS

One or more thrombotic risk factors were found in 68% and > or =2 factors in 37% of patients. Higher necroinflammatory activity was independently associated with higher prothrombin time (p=0.003), alanine aminotransferase level (p=0.011), and histological staging (p=0.018). Patients with staging scores of 4-6 compared with those with scores of 0-3 more frequently had deficiency of protein C (24% v 3%; p=0.007), antithrombin III (28% v 5%; p=0.005), and plasminogen (19% v 2%; p=0.03), and a trend for more frequent activated protein C resistance (8% v 0%; p=0.075). The presence of > or =1 significant thrombotic risk factor was observed in 11/25 (44%) patients with staging scores of 4-6 and in 6/65 (9%) patients with scores of 0-3 (p<0.001), being the only variable independently associated with advanced staging (odds ratio 2.4, p=0.02).

CONCLUSIONS

Thrombotic risk factors are frequently detected in patients with chronic viral hepatitis and the presence of > or =1 significant factor is associated with more advanced fibrosis. Whether the association of such thrombophilic conditions with advanced fibrosis is a primary or secondary phenomenon and whether their development in combination with local inflammation accelerate the progression of liver fibrosis need further evaluation.

Homocysteine and other vascular risk factors in patients with phenylketonuria on a diet

The aim of this study was to investigate the known risk factors, such as lipids, homocysteine and endothelin, for the development of coronary artery disease (CAD) in phenylketonuria (PKU) patients, depending on their diet. The PKU patients (n = 74) were divided into two groups. Group A (n = 34; mean age 6.78 +/- 1.5 y) adhered strictly to a diet and group B (n = 40; mean age 8.0 +/- 3.2 y) did not comply with the diet. The control group comprised 50 healthy non-PKU children. All groups were evaluated for blood levels of homocysteine and vitamin B6 by high-performance liquid chromatography, vitamin B12 and folate in serum by a radioassay, lipids by a routine method, and lipoprotein(a) and endothelin-1 with an immunoassay. Homocysteine levels (28.65 +/- 3.3 micromol l(-1)) were increased in group A compared with group B (6.86 +/- 1.6 micromol l(-1)) and the controls (6.9 +/- 2.0 micromol l(-1)) (p < 0.001). Vitamin B6 (10.7 +/- 10.9 nmol l(-1)), vitamin B12 (98.5 +/- 22.3 pmol l(-1)), folate (2.35 +/- 1.3 nmol l(-1)) and lipids were decreased in group A. The other vascular risk factors, which were not dependent on diet [lipoprotein(a) and endothelin-1], did not differ among the three groups.

CONCLUSION

PKU patients on a strict diet had low vitamin B6, vitamin B12 and folate levels resulting in moderate hyperhomocysteinaemia. The evaluation of these vitamins at short intervals and their supplementation could be an early measure in the prevention of CAD.

Hypoxia differentially enhances the effects of transforming growth factor-beta isoforms on the synthesis and secretion of glycosaminoglycans by human lung fibroblasts

Interstitial lung diseases associated with hypoxia, such as lung fibrosis, are characterized by enhanced production of transforming growth factor-beta (TGF-beta) and increased deposition of extracellular matrix (ECM) molecules, including glycosaminoglycans (GAGs). In this study, we investigated the effect of hypoxia (3% O(2)) on TGF-beta-induced GAG synthesis by primary human pulmonary fibroblasts, established from lung biopsies. Total GAG synthesis was assessed by the incorporation of [(3)H]glucosamine into GAGs associated with the cell layer (cells and ECM) or secreted in the medium. GAGs were isolated and purified by gel filtration, fractionated by electrophoresis on cellulose acetate membranes, and characterized using GAG-degrading enzymes. GAG molecules identified in the cell layer and the medium were: hyaluronic acid, and chondroitin, dermatan, and heparan sulfates. All TGF-beta isoforms time dependently induced [(3)H]glucosamine incorporation into GAGs of the cell layer or the medium. Characterization of individual GAG molecules indicated that this was attributed to dermatan and heparan sulfates in the cell layer and to hyaluronic acid and chondroitin and dermatan sulfates in the medium. Hypoxia enhanced the effect of all TGF-beta isoforms, particularly that of TGF-beta3, on the secretion of hyaluronic acid and chondroitin and dermatan sulfates. In the cell layer, hypoxia stimulated only the effect of TGF-beta2-induced [(3)H]glucosamine incorporation into GAGs. Our data indicate that hypoxia differentially enhances the effect of TGF-beta isoforms on the secretion and deposition of GAGs and may hasten ECM remodeling associated with the pathogenesis of lung fibrosis.

Losartan inhibits the angiotensin II-induced modifications on fibrinolysis and matrix deposition by primary human vascular smooth muscle cells

Disorders in the fibrinolytic and renin-angiotensin-aldosterone systems and excessive extracellular matrix (ECM) deposition are determinant factors in several pathologic manifestations of vascular and cardiac tissue. We used primary human vascular smooth muscle cells (VSMC) and studied the effects of losartan on angiotensin II (Ang II)-mediated (a) DNA synthesis, (b) secretion of tissue-type plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1), (c) secretion of matrix metalloprotease-2 (MMP-2) activity and tissue inhibitors of MMPs (TIMPs), and (d) synthesis of glycosaminoglycans. VSMC cultures, established from human pulmonary arteries, were treated with Ang II (0.1 nM -1 microM ) and/or losartan (0.1-10 microM ), for 24 or 48 h. DNA synthesis was assessed by incorporation of 3 H-thymidine into VSMC, secreted tPA, PAI-1, and TIMPs by enzyme-linked immunosorbent assay, MMP-2 activity by gelatin zymography, and glycosaminoglycan synthesis by 3 H-glucosamine incorporation. Ang II (1 microM ) enhanced DNA synthesis and secretion of PAI-1 and glycosaminoglycans and decreased secretion of MMP-2 activity and tPA, whereas it had no effect on secretion of TIMPs and glycosaminoglycans associated with cell layers. The Ang II-mediated effects were reversed by losartan, in a concentration-dependent manner. Losartan alone increased secretion of tPA, MMP-2 activity, and TIMPs and decreased secretion of PAI-1. These results indicate that AT 1 receptors are implicated in Ang II-mediated disorders of fibrinolysis and excessive ECM deposition by VSMC.

Hypoxia modifies the effect of PDGF on glycosaminoglycan synthesis by primary human lung cells

Hypoxia, a consequence of interstitial lung diseases, may lead to secondary pulmonary hypertension and pulmonary vascular remodeling. Hypoxia induces activation and proliferation of lung cells and enhances the deposition of extracellular matrix including glycosaminoglycans (GAGs). To elucidate the cell biological mechanisms underlying the development of secondary pulmonary hypertension, we studied the effect of hypoxia on GAG synthesis by human lung cells. GAG synthesis was measured by incorporation of [(3)H]glucosamine; GAGs were isolated, purified, and characterized with GAG-degrading enzymes. Fibroblasts and vascular smooth muscle cells (VSMCs) synthesized hyaluronic acid, heparan sulfate, and chondroitin sulfates, whereas dermatan sulfate was found only in fibroblasts. Hypoxia did not influence the size or charge of the individual GAGs. However, hypoxia inhibited platelet-derived growth factor-induced [(3)H]glucosamine incorporation in secreted GAGs, especially hyaluronic acid, in VSMCs. In contrast, it stimulated GAG secretion, specifically heparan sulfate, by fibroblasts. Our results indicate that hypoxia induces modifications in GAG synthesis by human lung VSMCs and fibroblasts that may be correlated to pathophysiological manifestations in lung diseases causing hypoxia.

Tissue structure-specific distribution of glycosaminoglycans in the human penis

The aim of this work was to isolate and characterise the glycosaminoglycans present in the different tissue structures of the human penis in view of their potentially significant role in the physiology of erection. Penile tissue samples were obtained from patients who underwent penectomy and were subsequently dissected into individual tissue structures. Total glycosaminoglycans were isolated and purified from tunica albuginea, corpora cavernosa and corpus spongiosum, following tissue mincing, ultrasonication, lipid extraction, extensive digestion with pronase and DNase, treatment with alkali-borohydride and ethanol precipitation. Isolated glycosaminoglycans were separated by cellulose acetate electrophoresis and fractionated by anion exchange chromatography on DEAE Sephacel columns. Different glycosaminoglycan fractions were identified using glycosaminoglycan-degrading enzymes of known specificity. Gradient polyacrylamide gel electrophoresis was used to determine the average molecular mass of the glycosaminoglycans. The corpus cavernosum and the corpus spongiosum extracts contained almost twice the amount of glycosaminoglycan-associated uronic acids as compared to the tunical extracts (1.47+/-0.09, and 1.49+/-0.15 as opposed to 0.75+/-0.15 microg/mg dry defatted tissue, respectively; S.E.M., n=5). With the exception of hyaluronic acid, the relative amount of individual glycosaminoglycan types varied significantly among extracts of different origin. Heparan sulphate was more abundant in cavernosal, dermatan sulphate in tunical, and chondroitin-6-sulphate in corpus spongiosum extracts. No structure-specific differences were detected with respect to the molecular mass distribution of each glycosaminoglycan type. Our study shows that the different structures of the human penis produce distinct profiles of glycosaminoglycans, which are well suited to the individual functional characteristics of these structures.

Benign hyperplasia of the human prostate is associated with tissue enrichment in chondroitin sulphate of wide size distribution

BACKGROUND

Benign prostatic hyperplasia (BPH) involves qualitative and quantitative alterations in extracellular matrix (ECM) components affecting stromal-epithelial interactions. Glycosaminoglycans (GAGs) are polysaccharide components of the ECM whose role in the development of BPH is under investigation.

METHODS

GAGs were extracted from human prostates of normal and BPH origin and were subsequently fractionated through DEAE-sephacel anion exchange chromatography. The isolated GAG fractions were identified through electrophoresis on cellulose acetate membranes and treatment with GAG-degrading enzymes of known specificity. Their size distribution was determined through gradient polyacrylamide gel electrophoresis.

RESULTS

Isolated prostatic GAGs included hyaluronic acid (HA), heparan sulphate (HS), and a mixture of dermatan sulphate (DS) and chondroitin sulphate (CS). The CS/DS ratio was significantly higher in hyperplastic as compared to normal prostates. A difference was also observed with respect to the apparent molecular mass of the DS-CS mixture, which reflects the CS enrichment in BPH. GAGs isolated from hyperplastic prostates were more diverse in size as compared to the corresponding glycans from normal prostates.

CONCLUSIONS

The apparent increase in CS and decrease in DS content in prostates of patients with BPH is in good agreement with the pathological manifestation of increased cell proliferation in hyperplastic prostate tissue, since these glycan molecules have been reported to increase and decrease cell proliferation, respectively. Identification of the responsible enzymes involved in the homeostasis of CS and DS may provide alternative targets for pharmacological intervention.

Glycosaminoglycan analysis in brain stems from animals infected with the bovine spongiform encephalopathy agent

Increasing evidence suggests that the pathological alterations observed in brains affected by neurodegenerative disorders such as Creutzfeldt-Jakob disease and Alzheimer's disease also involve changes in glycosaminoglycans (GAGs). In the present study, we have isolated, purified, and characterized total GAGs from brain stems of healthy cows or those infected with the bovine spongiform encephalopathy (BSE) agent and we report on the differences between the two groups. Purification of the GAGs was achieved by gel filtration after homogenization, delipidation, and sequential treatment with pronase, DNase, and alkali borohydride. Fractionation of the total GAGs by Superose 6 gel filtration and HPLC revealed four major fractions, with average molecular masses of 360, 180, 15, and 2.3 kDa, respectively, both in controls and infected tissues. Enzymatic characterization, using GAG-degrading enzymes, showed that in both infected and normal brain stems, the 360- and 180-kDa fractions correspond to hyaluronic acid, which was also the most abundant GAG, while the 15-kDa fractions correspond to chondroitin sulfates as well as heparan sulfate and dermatan sulfate, the latter being the least prominent GAG. Electrophoresis on cellulose acetate membranes revealed that the relative ratio of GAGs was not significantly modified in infected brain stems, compared to controls. However, total GAGs in infected brain stems was significantly decreased by approximately 40%, compared to controls, and this decrease applied equally to all of the above GAG fractions. The diminution observed in total GAGs in infected brain stems is in good agreement with the recently reported neuroprotective role of certain GAG molecules and offers an additional criterion for differential diagnosis of BSE-infected animals.