Distinct Expression Patterns of Fibrillar Collagen Types I, III, and V in Association with Mammary Gland Remodeling during Pregnancy, Lactation and Weaning

The mammary gland structurally and functionally remodels during pregnancy, during lactation and after weaning. There are three types of fibrillar collagens, types I, III, and V, in mammary stromal tissue. While the importance of the fibrillar structure of collagens for mammary morphogenesis has been suggested, the expression patterns of each type of fibrillar collagen in conjunction with mammary remodeling remain unclear. In this study, we investigated their expression patterns during pregnancy, parturition, lactation and involution. Type I collagen showed a well-developed fibril structure during pregnancy, but the fibrillar structure of type I collagen then became sparse at parturition and during lactation, which was concurrent with the downregulation of its mRNA and protein levels. The well-developed fibrillar structure of type I collagen reappeared after weaning. On the other hand, type V collagen showed a well-developed fibrillar structure and upregulation in the lactation period but not in the periods of pregnancy and involution. Type III collagen transiently developed a dense fibrillar network at the time of parturition and exhibited drastic increases in mRNA expression. These results indicate that each type of fibrillar collagen is distinctly involved in structural and functional remodeling in mammary glands during pregnancy, parturition, lactation, and involution after weaning. Furthermore, in vitro studies of mammary epithelial cells showed regulatory effects of type I collagen on cell adhesion, cell proliferation, ductal branching, and β-casein secretion. Each type of fibrillar collagen may have different roles in defining the cellular microenvironment in conjunction with structural and functional mammary gland remodeling.

Histological features of restenosis associated with paclitaxel drug-coated balloon: implications for therapy

PURPOSE

To investigate the cellular and extracellular changes induced by drug-coated balloons (DCB) in the treatment of superficial femoral artery (SFA) restenosis, and to compare histopathological features with those observed after plain old balloon angioplasty (POBA) from the same patients.

METHODS AND RESULTS

Plaque samples for five patients with SFA restenosis (first-time) after POBA were collected using atherectomy and DCB. These samples constitute the POBA restenosis group. The same five patients developed recurrent restenosis (RR) after DCB, at the same intervention site. These SFA-RR lesions were again treated using atherectomy and POBA. These samples constitute the DCB restenosis group. DCB restenosis group plaques showed significant reduction in neointima, smooth muscle cells, fibroblast densities, and Ki67 index; and increase in caspase 3, features of apoptosis and type III collagen deposition in comparison to the POBA restenosis group.

CONCLUSION

Plaque tissue from the DCB restenosis group show reductions in neointimal thickness, cellularity, and cellular proliferation, along with increased apoptosis, and Type III collagen content. These results suggest a different mechanistic pathway for DCB restenosis, in which neointimal proliferation is reduced but reparative fibrosis is increased. The treatment for SFA-RR after DCB may therefore benefit from different forms of therapy including scaffolding, rather than recurrent anti-proliferative therapy.

[Experimental study of platelet-rich plasma in treatment of Achilles tendinopathy in rabbits]

OBJECTIVE

To explore the effect of platelet-rich plasma (PRP) in treatment of Achilles tendinopathy in rabbits, and provide experimental evidence for the clinical application of PRP in treatment of Achilles tendinopathy.

METHODS

Forty-eight adult New Zealand white rabbits, weighing 2.5-3.0 kg, male or female, were randomly divided into model group (group A), model control group (group B), model+treatment control group (group C), model+treatment group (group D), with 12 in each group. The rabbits were injected with type Ⅰ collagenase to prepare Achilles tendinopathy models in groups A, C, and D, and with an equal dose of normal saline in group B. The blood from the central artery of rabbit ear was taken to preprare PRP by secondary centrifugation in group D. The results of platelet counts showed that PRP platelets reached 3 to 5 times the whole blood. After the model was prepared, the rabbits in groups C and D were injected with physiological saline and autologous PRP at the molding site respectively, once a week, 0.8 mL each time for 4 weeks. At 1 week after PRP injection, the relative hardness (expressed as HRD%) of Achilles tendon was evaluated by ultrasound elastic quantitative imaging detection technique; the maximum breaking load of Achilles tendon was measured by universal electronic tensile testing machine; the contents of collagen type Ⅰ and Ⅲ were determined by ELISA; and the morphology of Achilles tendon collagen fibers was observed by HE and Masson stainings.

RESULTS

All animals survived during the experiment. The results of ultrasound elastic quantitative imaging and mechanical tests showed that the HRD% and the maximum breaking load were significantly lower in group A than in group B ( P<0.05) and in group C than in group D ( P<0.05). The results of ELISA showed that the content of collagen type Ⅰ was significantly lower in group A than in group B ( P<0.05) and in group C than in group D ( P<0.05); the content of collagen type Ⅲ was significantly higher in group A than in group B ( P<0.05) and in group D than in group C ( P<0.05). HE and Masson stainings showed that the Achilles tendon collagen fibers were irregularly curled and the structure was severely damaged in group A; the fibers were parallel and ordered, and the structure was complete in group B; the fibers were irregularly curled and structurally disordered in group C; the fibers were slightly curled and the structure was relatively complete in group D.

CONCLUSION

A rabbit model of Achilles tendinopathy can be reconstructed by type Ⅰ collagenase injection. PRP treatment can increase the Achilles tendon hardness and maximum breaking load, up-regulate the expression level of collagen type Ⅰ and Ⅲ, improve the structure of Achilles tendon collagen fiber, and promote the repair in rabbit Achilles tendinopathy model.

EFFECTS OF RENAL DYSFUNCTION ON HEALING OF COLONIC ANASTOMOSIS: EXPERIMENTAL STUDY IN WISTAR RATS

BACKGROUND

Chronic kidney disease affects more than 500 million people worldwide. In this context, the uremic toxins present are related to worsening in tissue healing.

AIM

Evaluate on healing of colonic anastomosis in uremic rats, serum and anatomopathological indicators, which may be related to the change tissue repair process.

METHODS

Twenty Wistar rats, were randomly separated into two groups. In the sham group they were submitted to 5/6 nephrectomy simulation in left kidney, simulation right nephrectomy, median laparotomy, colotomy and colorraphy. In the uremia group, they were submitted to 5/6 nephrectomy of the left kidney, total nephrectomy of the right kidney and median laparotomy, colotomy and colorraphy. Were collected for serum urea, creatinine and CRP dosages and the colonic segments were studied for evaluation of granulation tissue, collagen maturation, microvascular and myofibroblasts density, and cell viability. Through histochemical processing, microvascular density was evaluated by anti-CD34 monoclonal antibody marking, cell viability by cell proliferation nuclear antigen screening and myofibroblasts density with monoclonal anti-α-actin antibody. Computerized histometry was used for evaluations of collagens type I and III by the coloration of picrosirius.

RESULTS

The group submitted to nephrectomy 5/6, compared to the sham group, show urea increase (p<0.0000) and higher C reactive protein (p=0.0142). Decrease of granulation tissue formation (border reepithelialization p=0,0196, angiofibroblast proliferation p=0.0379), mean collagen I (p=0,0009) and collagen III (p=0,016), microvascular density (p=0,0074), cell proliferation nuclear antigen (p<0,0000) and myofibroblasts (p<0,0001).

CONCLUSION

The uremia induced by nephrectomy 5/6 model establishes negative impact in the colonic wound healing.

Sorafenib and praziquantel synergistically attenuate Schistosoma japonicum-induced liver fibrosis in mice

Liver fibrosis is an important process that occurs in most types of chronic liver diseases and often results in the end stage of liver diseases, such as cirrhosis, portal hypertension, and hepatocellular carcinoma. Sorafenib, a multiple tyrosine kinase inhibitor, has been shown to inhibit liver fibrosis in multiple experimental fibrosis mouse and rat models. The aim of this study was to test the therapeutic effect of sorafenib on liver fibrosis induced by infection with a parasite, Schistosoma japonicum, in mice. Mice were percutaneously infected through the abdomen with Schistosoma cercariae to develop a schistosomula liver fibrosis model. Eight weeks after infection, infected mice were treated with the anti-parasitic agent praziquantel for 2 days and sorafenib for 2 weeks. Hepatic histopathological changes were assessed using hematoxylin and eosin (HE) and Masson's trichome staining. The hepatic expression levels of collagen I, collagen III, alpha-smooth muscle actin (α-SMA), platelet-derived growth factor (PDGF), and PDGF receptor-beta (PDGFR-β) were analyzed by immunohistochemistry and western blot. Praziquantel administration alone but not sorafenib reduced liver fibrosis, and the combination of praziquantel and sorafenib significantly attenuated liver fibrosis in S. japonicum-infected mice. Moreover, sorafenib plus praziquantel markedly decreased the hepatic deposition of collagen and expression of fibrogenic genes in these mice. In conclusion, the use of sorafenib following praziquantel treatment may represent a potential therapeutic strategy for liver fibrosis induced by S. japonicum in patients.

Collagen I and III in women with diastasis recti

OBJECTIVES

Interest in elucidating the etiology of hernias has encouraged countless studies of musculoaponeurotic structures in individuals with and without hernias. Studies of hernia patients have firmly demonstrated a correlation between hernias and collagen alterations in their fascia. Diastasis recti is an increased width of the abdominal midline that is exclusively composed of interlacing aponeurotic expansions of the anterolateral abdominal muscles. The condition is common among women undergoing abdominoplasty, and many factors, not only mechanical, play a role. The goal of this study is to evaluate and compare collagen type I and III levels in the midline fascia of women with and without diastasis recti to report their possible influence on this condition.

METHODS

This is a case-control study nested within a surgical cohort of 18 women with diastasis recti and 18 women without the condition (cases and controls, respectively). Fascia from the midline of the abdominal wall was collected and analyzed through immunohistochemistry using polyclonal antibodies to collagen type I and III.

RESULTS

Both type I and type III collagen were less abundant in women with diastasis recti than in those without the condition, and the difference was statistically significant (p<0.001).

CONCLUSION

Low collagen type I and type III levels in the midline of the abdominal wall may play a key role in the development of diastasis recti.

Angiogenesis - a crucial step in breast cancer growth, progression and dissemination by Raman imaging

Combined micro-Raman imaging and AFM imaging are efficient methods for analyzing human tissue due to their high spatial and spectral resolution as well as sensitivity to subtle chemical, structural and topographical changes. The aim of this study was to determine biochemical composition and mechanical topography around blood vessels in the tumor mass of human breast tissue. Significant alterations of the chemical composition and structural architecture around the blood vessel were found compared to the normal breast tissue. A pronounced increase of collagen-fibroblast-glycocalyx network, as well as enhanced lactic acid, and glycogen activity in patients affected by breast cancer were reported.

Vascular Ehlers-Danlos syndrome with cryptorchidism, recurrent pneumothorax, and pulmonary capillary hemangiomatosis-like foci: A case report

RATIONALE

Vascular Ehlers-Danlos syndrome (vEDS) is a rare autosomal dominant inherited collagen disorder caused by defects or deficiency of pro-alpha 1 chain of type III procollagen encoded by COL3A1. vEDS is characterized not only by soft tissue manifestations including hyperextensibility of skin and joint hypermobility but also by early mortality due to rupture of arteries or vital organs. Although pulmonary complications are not common, vEDS cases complicated by pneumothorax, hemothorax, or intrapulmonary hematoma have been reported. When a patient initially presents only with pulmonary complications, it is not easy for clinicians to suspect vEDS.

PATIENT CONCERNS

We report a case of an 18-year-old high school student, with a past history of cryptorchidism, presenting with recurrent pneumothorax.

DIAGNOSES

Routine laboratory findings were unremarkable. Chest high resolution computed tomographic scan showed age-unmatched hyperinflation of both lungs, atypical cystic changes and multifocal ground glass opacities scattered in both lower lobes. His slender body shape, hyperflexible joints, and hyperextensible skin provided clue to suspicion of a possible connective tissue disorder.

INTERVENTIONS

The histological examination of the lung lesions showed excessive capillary proliferation in the pulmonary interstitium and pleura allowing the diagnosis of pulmonary capillary hemangiomatosis (PCH)-like foci. Genetic study revealed COL3A1 gene splicing site mutation confirming his diagnosis as vEDS.

OUTCOMES

Although his diagnosis vEDS is notorious for fatal vascular complication, there was no evidence of such complication at presentation. Fortunately, he has been followed up for 10 months without pulmonary or vascular complications.

LESSONS

To the best of our knowledge, both cryptorchidism and PCH-like foci have never been reported yet as complications of vEDS, suggesting our case might be a new variant of this condition. This case emphasizes the importance of comprehensive physical examination and history-taking, and the clinical suspicion of a possible connective tissue disorder when we encounter cases with atypical presentation and/or unique chest radiologic findings especially in young patients.

Collagenofibrotic (Collagen Type III) glomerulopathy in association with diabetic nephropathy

Collagenofìbrotic (collagen type III) glomerulopathy (CG) is a rare nonimmune-mediated glomerular disease. It is characterized by massive deposition of organized collagen type III fibers, which is localized in the mesangial and subendothelial glomerular areas and associated with increased serum levels of procollagen type III peptide. Association with systemic diseases and malignancies is extremely rare. Herein, we present a case of a nine-year-old girl, known case of type I diabetes mellitus, who presented with fever, nephrotic range proteinuria, generalized edema, and hypertension. Clinical examination did not show nail abnormalities or bone abnormalities. Renal biopsy revealed mesangial expansion and remarkable narrowing and obliteration of the glomerular capillaries by pale, amorphous material. Immunohistochemical study demonstrated diffuse linear glomerular capillary and tubular basement membrane staining for immunoglobulin G (IgG) and albumin. Ultrastructural examination identified massive mesangial and sub-endothelial deposition of dense frayed, curvilinear banded fibers with characteristic features of type III collagen. The patient was diagnosed to have combined CG and diabetic nephropathy (DN). This is the first report of CG in association with diabetic changes in renal biopsy. In this report, we describe the clinicopathological characteristics of this disease, review CG in pediatric population, and explore its association with DN.

The Effects of Bone Marrow-Derived Mesenchymal Stem Cells and Fascia Wrap Application to Anterior Cruciate Ligament Tissue Engineering

After an anterior cruciate ligament (ACL) injury, surgical reconstructions are necessary in most cases, either with autografts, allografts, or artificial ligaments. Potential tissue-engineered ligaments would circumvent the disadvantages apparent in these methods. While seeding of mesenchymal stem cells (MSCs) and fascia wrap could potentially improve tissue regeneration and mechanical properties, their exact roles were evaluated in the current study. Knitted biodegradable scaffolds of poly-L-lactic acid (PLLA) and poly-glycolic-lactic acid (PGLA) yarns were used to reconstruct ACL in 48 rabbits. These were divided into four equal groups: only knitted scaffolds were used in group I; knitted scaffolds and mesenchymal stem cells were used in group II; knitted scaffolds, MSCs, and fascia lata were used in group III; knitted scaffolds and fascia lata were used in group IV. Carboxyfluorescein diacetate (CFDA)-labeled MSCs were used to trace the fate of seeded cells in groups II and III. Histology, Western blot analysis, and mechanical properties of reconstructed ACL were analyzed after 20 weeks. Fibroblast ingrowths were seen in all four groups while CFDA-labeled MSCs could be found after 8 weeks of implantation in groups II and III. Both the amount of collagen type I and collagen type III in groups III and IV were significantly higher than in group II, which was much higher than in group I. Both maximal tensile loads and stiffness of the reconstructed ACLs in groups I, II, III, and IV were significantly lower than normal controls after 20 weeks of implantation. It is concluded that MSCs could promote synthesis of collagen type I and collagen type III in tissue-engineered ligaments, while fascia wraps have stronger effects. Both MSC seeding and fascia wrap could not enhance ultimate tensile load and stiffness.

Mesenchymal Stem Cells Acquire Characteristics of Cells in the Periodontal Ligament in vitro

Mesenchymal stem cells differentiate into multiple types of cells derived from mesenchyme. Periodontal ligament cells are primarily derived from mesenchyme; thus, we expected mesenchymal stem cells to differentiate into periodontal ligament. Using a combination of immunohistochemistry and in situ hybridization on co-cultures of mesenchymal stem cells and periodontal ligament, we observed a significant increase in mesenchymal stem cells’ expression of osteocalcin and osteopontin and a significant decrease in expression of bone sialoprotein, characteristics of periodontal ligament in vivo. Increased osteopontin and osteocalcin and decreased bone sialoprotein expression was detected within 7 days and maintained through 21 days of co-culture. We conclude that contact or factors from periodontal ligament induced mesenchymal stem cells to obtain periodontal-ligament-like characteristics. Importantly, analysis of the data suggests the feasibility of utilizing mesenchymal stem cells in clinical applications for repairing and/or regenerating periodontal tissue.

Primary biliary cirrhosis degree assessment by acoustic radiation force impulse imaging and hepatic fibrosis indicators

AIM: To evaluate the assessment of primary biliary cirrhosis degree by acoustic radiation force impulse imaging (ARFI) and hepatic fibrosis indicators.

METHODS: One hundred and twenty patients who developed liver cirrhosis secondary to primary biliary cirrhosis were selected as the observation group, with the degree of patient liver cirrhosis graded by Child-Pugh (CP) score. Sixty healthy individuals were selected as the control group. The four indicators of hepatic fibrosis were detected in all research objects, including hyaluronic acid (HA), laminin (LN), type III collagen (PC III), and type IV collagen (IV-C). The liver parenchyma hardness value (LS) was then measured by ARFI technique. LS and the four indicators of liver fibrosis (HA, LN, PC III, and IV-C) were observed in different grade CP scores. The diagnostic value of LS and the four indicators of liver fibrosis in determining liver cirrhosis degree with PBC, whether used alone or in combination, were analyzed by receiver operating characteristic (ROC) curve.

RESULTS: LS and the four indicators of liver fibrosis within the three classes (A, B, and C) of CP scores in the observation group were higher than in the control group, with C class > B class > A class; the differences were statistically significant (P < 0.01). Although AUC values of LS within the three classes of CP scores were higher than in the four indicators of liver fibrosis, sensitivity and specificity were unstable. The ROC curves of LS combined with the four indicators of liver fibrosis revealed that: AUC and sensitivity in all indicators combined in the A class of CP score were higher than in LS alone, albeit with slightly decreased specificity; AUC and specificity in all indicators combined in the B class of CP score were higher than in LS alone, with unchanged sensitivity; AUC values (0.967), sensitivity (97.4%), and specificity (90%) of all indicators combined in the C class of CP score were higher than in LS alone (0.936, 92.1%, 83.3%).

CONCLUSION: The diagnostic value of PBC cirrhosis degree in liver cirrhosis degree assessment by ARFI combined with the four indicators of serum liver fibrosis is of satisfactory effectiveness and has important clinical application value.

The Role of Interleukin-13 in Patients with Rheumatic Valvular Fibrosis: A Clinical and Histological Study

BACKGROUND AND AIM OF THE STUDY

Interleukin (IL)-13 is a major inducer of fibrosis in many chronic infectious diseases, yet few studies have reported its role in valvular fibrosis in patients with rheumatic heart disease (RHD). The study aim was to investigate the role of IL-13 in mitral valvular fibrosis in patients with RHD.

METHODS

Peripheral blood samples were collected from surgical patients with RHD (n = 18) and from healthy controls (n = 9). Serum levels of IL-13 and interferon (IFN)-gamma were analyzed using ELISA. Rheumatic mitral valves removed from surgical patients with RHD, and normal mitral valves, were obtained at autopsy. The expression and distribution of collagen I, collagen III, and IL-13Ralpha1 were examined by immunohistochemical staining, the degree of which was measured using computed imaging analysis.

RESULTS

Higher IL-13 levels were observed in RHD patients (15.16 +/- 9.62 pg/ml; p < 0.05) than in healthy controls (7.78 +/- 3.87 pg/ml). RHD patients had high levels of IFN-gamma (9.95 +/- 0.77 pg/ml; p <0.05) compared to healthy controls (5.95 +/- 0.69 pg/ml). Immunohistochemistry showed that, compared to normal valves, rheumatic mitral valves expressed high levels of collagen I (0.01931 +/- 0.00159 versus 0.01183 +/- 0.00207; p < 0.05), collagen III (0.00726 +/- 0.00078 versus 0.00342 +/- 0.00124; p <0.05), and IL-13Rcxl (0.00454 +/- 0.00086 versus 0.00017 +/- 0.00008; p <0.01). Collagens I and III were each expressed in heart interstitial cells, while IL-13Ralpha1 was expressed in the endothelial cells and smooth muscle cells of the blood vessels, and in interstitial cells.

CONCLUSION

Patients with RHD showed increased serum levels of IL-13 compared to healthy controls. IFN-gamma levels were clearly different among RHD patients and healthy controls. The expression of collagens I and III and IL-13Ralpha1 was higher in rheumatic mitral valves compared to normal mitral valves. IL-13 may induce mitral valvular fibrosis in RHD.

[Improvement in cardiac morphology and function in young rats with dilated cardiomyopathy by recombinant human growth hormone]

OBJECTIVE

To investigate the effects of recombinant human growth hormone (rhGH) on the morphology and function of the left cardiac ventricle in young rats with dilated cardiomyopathy (DCM), and to evaluate the efficacy and safety of rhGH in the treatment of DCM.

METHODS

Sixty male Sprague-Dawley rats were randomly and equally assigned to control group, DCM group, and rhGH group. Furazolidone (0.25 mg/g) was given by gavage for 12 weeks to prepare the DCM model. Rats in the rhGH group received an intraperitoneal injection of rhGH (0.15 U/kg) once per day for 12 weeks, while rats in the DCM group received an equal volume of normal saline instead. Rats in the control group did not receive any treatment. Cardiac indices, serum biochemical parameters, hemodynamic indices, cardiac histopathological changes, and levels of myocardial collagen fibrils in each group were determined using Doppler echocardiography, enzyme-linked immunosorbent assay, multi-channel physiological recorder, light and electron microscopy, and picrosirius red staining plus polarization microscopy, respectively.

RESULTS

Compared with the control group, rats in the DCM group had significantly increased cardiac chamber size, significantly reduced ventricular wall thickness, and significantly decreased fractional shortening (FS) and ejection fraction (EF) (P<0.05). Rats in the rhGH group had significantly improved cardiac chamber size, ventricular wall thickness, FS, and EF compared with the DCM group (P<0.05). Those indices in the rhGH group were similar to those in the control group (P>0.05). There were significant differences in serum biochemical parameters and hemodynamic indices between the DCM and control groups (P<0.05). Compared with the DCM group, the rhGH group had significantly improved serum biochemical parameters and hemodynamic indices (P<0.05). Those indices in the rhGH group were similar to those in the control group (P>0.05), except for the levels of insulin-like growth factor-1 and insulin-like growth factor-binding protein-3. The DCM group had a significantly higher collagen type I/collagen type III (Col I/Col III) ratio in the myocardium than the control group (P<0.05), and there was no significant difference in the Col I/Col III ratio between the control and rhGH groups (P>0.05).

CONCLUSIONS

rhGH plays a certain role in improvement in the morphology and function of the left cardiac ventricle in young rats with DCM.

Tanshinone IIA attenuates interleukin-17A-induced systemic sclerosis patient-derived dermal vascular smooth muscle cell activation via inhibition of the extracellular signal-regulated kinase signaling pathway

OBJECTIVE

Salvia miltiorrhiza has long been used to treat systemic sclerosis. Tanshinone IIA, one of the phytochemicals derived from the roots of Salvia miltiorrhiza, exhibits multiple biological activities. The present study aimed to investigate whether tanshinone IIA has an effect on the interleukin-17A-induced functional activation of systemic sclerosis patient-derived dermal vascular smooth muscle cells.

METHODS

Systemic sclerosis patient-derived dermal vascular smooth muscle cells were incubated with various dosages of tanshinone IIA in the presence of interleukin-17A or the serum of systemic sclerosis patients. Cell proliferation was assessed using Cell Counting Kit-8. The expression of collagen 1 and 3 in cells was evaluated by immunofluorescence. Cell migration was measured using a transwell assay. The expression of phospho-extracellular signal-regulated kinase was detected by Western blotting.

RESULTS

Our data demonstrate that tanshinone IIA exerts an inhibitory effect on interleukin-17A-induced systemic sclerosis patient-derived dermal vascular smooth muscle cell proliferation, collagen synthesis and migration.

CONCLUSION

These findings suggest that tanshinone IIA might serve as a promising therapeutic agent for the treatment of systemic sclerosis.

Does the histopathologic pattern of the ureteropelvic junction affect the outcome of pyeloplasty

PURPOSE

To investigate the effects of the histopathologic pattern of obstructed ureteropelvic junction (UPJ) specimens, including collagen type 3, elastin, fibrosis and Cajal cells, on the outcome of pyeloplasty.

MATERIALS AND METHODS

Histopathological specimens obtained following Anderson-Hynes pyeloplasty from 52 patients with intrinsic ureteropelvic junction obstruction (UPJO) between January 2005 and January 2008 were evaluated histopathologically. Patients with extrinsic or secondary UPJO were excluded. Preoperative and postoperative radiographic evaluations were performed either via diuretic renography or intravenous pyelography, or both. Six months post-surgery the patients were divided into 2 groups, as successful surgery (group 1) and unsuccessful surgery (group 2). Histopathological findings (collagen type 3, elastin, fibrosis and Cajal cells) in each group were statistically compared.

RESULTS

The study included 52 patients (21 female and 31 male). Mean age of the entire study population was 39.42 ± 14.5 years, versus 39.63 ± 14.9 years in group 1 (n = 47) and 37.4 ± 10.0 years in group 2 (n = 5). Median follow-up was 18 months. There weren't any significant differences in collagen type 3, elastin, fibrosis, or Cajal cells between the 2 groups (P > .05).

CONCLUSION

The histopathologic pattern of UPJ was not a factor associated with the success of pyeloplasty. Based on the present findings, we conclude that surgical technique is more important than the histopathologic pattern of UPJ for the successful treatment of UPJO.

Abnormalities in collagen composition may contribute to the pathogenesis of hemorrhoids: morphometric analysis

Purpose

While hemorrhoidal disease is common, its etiology remains unclear. It has been postulated that disturbances in collagen lead to reduced connective tissue stability, and in turn to the development of hemorrhoidal disease. We aimed to compare the quality and quantity of collagen in patients with hemorrhoidal disease versus normal controls.

Methods

Specimens from 57 patients with grade III or IV internal hemorrhoids undergoing hemorrhoidectomy between 2006 and 2011 were evaluated. Samples from 20 human cadavers without hemorrhoidal disease served as controls. Quality of collagen was analyzed by collagen I/III ratio, and quantity of collagen was determined by collagen/protein ratio. The study group was subdivided into gender and age subgroups.

Results

The male:female ratios in the study and control groups were 30:27 and 10:10, respectively. Median age was significantly less in the study group [46.9 years (range 20–69)] compared to the control group [76 years (range 46–90)] with P < 0.05. Tissues from patients in the study group had significantly lower collagen I/III ratio as compared to the control group (4.4 ± 1.1 vs. 5.5 ± 0.6; P < 0.0001). Nevertheless, despite a trend toward lower collagen/protein ratio in the study group, it did not reach statistical significance (57 ± 42.4 vs. 73 ± 32.5 g/mg; P = 0.167). There was no difference in collagen I/III or collagen/protein ratios among different age groups and genders.

Conclusions

Hemorrhoidal tissues from patients with hemorrhoidal disease appear to have reduced mechanical stability as compared to normal controls.

Isolation and characterization of islet stellate cells in rat

The central role of PSCs in pancreatic fibrogenesis is well established. However, the mechanism responsible for the islet fibrosis presenting in the late stage of T2DM has not been fully elucidated. This study was designed to determine whether the endocrine pancreatic islets contain cells resembling PSCs. PSCs were isolated from pancreas using standard explants techniques. A similar method was used to acquire ISCs. Adherent ISCs with a stellate, angular morphology migrated from the edge of cultured islets within 48 h of primary culture. ISCs contained fewer lipid droplets than equivalent PSCs, and their rapid disappearance accompanied by the increased expression of α-SMA suggested that ISCs were more rapidly activated than PSCs in vitro. They expressed α-SMA, vimentin, GFAP and were positive for ECM components col-I, col-III and FN, all of which are characteristics of classical PSCs. However, ISCs differed from PSCs by having reduced rates of proliferation and migration in vitro. Our in vitro study shows that isolated islets contain a population of stellate cells which are phenotypically similar but not identical to PSCs. In view of the established role of PSCs in pancreatic fibrosis, we suggest that these may contribute to islet fibrosis in T2DM.

Periostin as a modulator of chronic cardiac remodeling after myocardial infarction

OBJECTIVE

After acute myocardial infarction, during the cardiac repair phase, periostin is released into the infarct and activates signaling pathways that are essential for the reparative process. However, the role of periostin in chronic cardiac remodeling after myocardial infarction remains to be elucidated. Therefore, the objective of this study was to investigate the relationship between tissue periostin and cardiac variables in the chronic cardiac remodeling induced by myocardial infarction.

METHODS

Male Wistar rats were assigned to 2 groups: a simulated surgery group (SHAM; n = 8) and a myocardial infarction group (myocardial infarction; n = 13). After 3 months, morphological, functional and biochemical analyses were performed. The data are expressed as means±SD or medians (including the lower and upper quartiles).

RESULTS

Myocardial infarctions induced increased left ventricular diastolic and systolic areas associated with a decreased fractional area change and a posterior wall shortening velocity. With regard to the extracellular matrix variables, the myocardial infarction group presented with higher values of periostin and types I and III collagen and higher interstitial collagen volume fractions and myocardial hydroxyproline concentrations. In addition, periostin was positively correlated with type III collagen levels (r = 0.673, p = 0.029) and diastolic (r = 0.678, p = 0.036) and systolic (r = 0.795, p = 0.006) left ventricular areas. Considering the relationship between periostin and the cardiac function variables, periostin was inversely correlated with both the fractional area change (r = -0.783, p = 0.008) and the posterior wall shortening velocity (r = -0.767, p = 0.012).

CONCLUSIONS

Periostin might be a modulator of deleterious cardiac remodeling in the chronic phase after myocardial infarction in rats.

[Histomorphological and biomechanical characteristics of decellularized bovine tendons]

OBJECTIVE

To investigate the effect of repeated freezing and thawing combining nuclease treatment on the decellularization of bovine tendons, and the morphology, structure, biochemical compositions, and mechanical properties of the decellularized tendons.

METHODS

A total of 48 fresh 1-day-old bovine Achilles tendons were randomly divided into 3 groups (n=16): fresh normal tendons (group A), repeated freezing and thawing for 5 times (liquid nitrogen refrigeration/37 degreeC thawing, group B), and repeated freezing and thawing combining nuclease processing for 24 hours (group C). In each group, 2 tendons were used for scanning electron microscope (SEM), 3 tendons for histological and immunohistochemical observations, 3 tendons for DNA content detection, and 8 tendons for biomechanical testing.

RESULTS

SEM observation indicated the intact, aligned, and densely packed collagen fibers with no disruption in groups A and B, and the slightly loose collagen fibers with little disruption in group C. The alcian blue staining, sirius red staining, and immunohistochemical staining showed that the most of glycosaminoglycan, collagen type I, collagen type III, and fibronectin in group C were retained after decellularization treatment. HE and DAPI staining showed that the cell nuclei between the collagen fibers were clearly visible in groups A and B; however, the cell nuclei between collagen fibers almost were invisible with a few residual nuclei on the endotendineum in group C. DNA quantitative detection confirmed that DNA content in group C [(0.05 +/-0.02) micr g/mg] was significantly lower than those in group A [(0.24 +/-0.12) micro g/mg] and group B [(0.16 +/-0.07) micro g/mg] (P < 0.05). Biomechanical testing showed that the values of tensile strength, failure strain, stiffness, and elastic modulus were different among 3 groups, but no significant difference was found (P > 0.05).

CONCLUSION

Repeated freezing and thawing combining nuclease processing can effectively remove the component of cells, and simultaneously retain the original collagen fibrous structure, morphology, most of the extracellular matrix compositions, and mechanical properties of the bovine tendons.

The effects of conjugated estrogen, raloxifene and soy extract on collagen in rat bones

OBJECTIVE

To evaluate the action of conjugated equine estrogen, raloxifene and isolated or combined genistein-rich soy extracts on collagen fibers in the bones of oophorectomized rats.

MATERIALS AND METHODS

Seventy female rats received testosterone propionate (0.1 µg/g) on the 9th day after birth. At 6 months of age, the rats were administered the vehicle (propylene glycol, 0.5 ml/day), and ten of the rats were randomly chosen to comprise the non-oophorectomized control group (GI). The other 60 rats were ovariectomized and randomized into six groups of ten as follows: GII, vehicle; GIII, conjugated equine estrogen (CEE), 50 µg/kg/day; GIV, raloxifene (RAL), 0.75 mg/kg/day; GV, genistein-rich soy extract (GSE), 300 mg/kg/day; GVI, CEE + GSE, 50 µg/kg/day + 300 mg/kg/day; and GVII, CEE + RAL, 50 µg/kg/day + 0.75 mg/kg/day. Three months after surgery, the drugs were administered for 60 consecutive days. All rats were euthanized, and their left tibiae were removed for histological routine. The histological sections were stained with hematoxylin-eosin, and picrosirius for evaluating bone microarchitecture. Types I and II collagen fibers were analyzed by immunofluorescence. Data analysis was carried out with ANOVA and Tukey's test.

RESULTS

Collagen reduction was significant in the GIII animals when compared to the other groups (p < 0.05). There was no significant difference in the thickness of collagen fibers among the groups. There was a greater quantity of type III collagen in GVI than in the other groups.

CONCLUSION

Our data indicate that conjugated equine estrogen improves bone quality because it increases the quantity of type I collagen while reducing the quantity of thin collagen fibers. In addition, the combination of CEE and raloxifene or genistein-rich soy extract is not as efficient as CEE itself to improve bone quality.

[Effects of delivery and oophorectomy on urethral collagen: an experimental study]

OBJECTIVE

Stereological evaluation of the concentration of type I and III collagen fibers in the urethral tissue of rats subjected to simulated labor and oophorectomy. To compare the concentrations of collagen between oophorectomized and non-oophorectomized rats.

MATERIAL AND METHOD

Sixty adult Wistar rats were divided into six groups. A group made up of virgin rats was used as control group and another group was made up of oophorectomized rats. Two groups underwent vaginal distention for 30 and 120 minutes, respectively. The two other groups were subjected to the same distension periods, followed by oophorectomy. Sixty days later, euthanasia and removal of urethral tissue was carried out for stereological analysis of type I and III collagen after staining with hematoxylin and eosin and picrosirius red.

RESULTS

A decrease in estrogen levels was observed in the oophorectomized rats. There was a reduction of type III collagen in the oophorectomized control group compared to the control group when analyzed independently. No significant differences were observed among the other groups. Type I collagen decreased in all groups compared to the control group. However, in the prolonged vaginal distension and oophorectomy group, these fibers increased.

CONCLUSION

In normal rats, simulation of labor does not alter the collagen III levels. In hypoestrogenic rats, the concentration of collagen type I and III decreased, except in those undergoing prolonged labor simulation in which collagen I increased.

[Morphological diagnosis of connective tissue dysplasia in patients, suffering postoperative abdominal hernia]

The results of treatment of 122 patients, to whom alloplasty for postoperative abdominal hernia (POAH) was performed, were analyzed. In 76 patients a connective tissue dysplasia (CTD) was diagnosed.Determination of a various types of collagen content in connective tissue of patients, suffering CTD, may confirm or exclude this diagnosis. Diagnostic significance has the enhancement of a collagen type III content in comparison with such of a type I by three times and more. The method of lectinohistochemical investigation of connective tissue was applied as a precision-enhancing method of a CTD diagnosis. Mosaic or diffuse loss of SNA, LABA, ConA receptors of lectins by collagen fascicles, which reflect carbohydrate determinants of dense and strong collagen fascicles, made of collagen type I, witness the CTD presence. Along with this, there was observed a lectin WGA receptors expression increase, which constitutes a marker of fascicular structures, made of collagen, predominantly type III and a lectin PNA receptors, which are revealed around vessels.

Anatase-based implants nanocoating on stem cells derived from adipose tissue

PURPOSE

The aim of this study was to investigate the effect of a new anatase coating with antibacterial properties (Bactercline anatase coating [BAC]) on dental implants in the commitment of stem cells derived from adipose tissue to osteoblasts.

MATERIALS AND METHODS

Using real-time reverse transcription polymerase chain reaction, the quantitative expression of specific genes, such as transcriptional factors (runx2 and sp7), bone-related genes (spp1, col1a1, col3a1, alpl, and fosl1), and mesenchymal stem cells marker (eng), was examined.

RESULTS

BAC caused induction of bone-related genes such as sp7, fosl1, alpl, and spp1. In contrast, the expression of runx2, col3a1, and col1a1 was decreased in stem cells treated with BAC with respect to untreated cells.

CONCLUSION

The obtained results are relevant to better understand the molecular mechanism of bone regeneration and as a model for comparing other materials with similar clinical effects.

Does the expression of transforming growth factor β-1: affect the outcome of the radiofrequency modified maze procedure in patients with rheumatic atrial fibrillation?

We investigated whether the expression of transforming growth factor β-1 in the left atrial appendage affected the outcome of the radiofrequency modified maze procedure in patients with rheumatic valve disease and long-standing persistent atrial fibrillation.Messenger RNA and protein expression of transforming growth factor β-1 and volume fractions of collagen types I and III were measured in 80 patients with rheumatic valve atrial fibrillation who underwent valve surgery with the radiofrequency modified maze procedure; the same was done in a control group of 20 patients with rheumatic valve disease and sinus rhythm who underwent valve surgery alone.At 6 months' follow-up, atrial fibrillation recurred in 24 of the 80 patients in the study group. The messenger RNA and protein expressions of transforming growth factor β-1, collagen type I volume fraction, and left atrial dimension had increased gradually in the control group and in the study subgroups that maintained sinus rhythm or relapsed into atrial fibrillation (P <0.05). The messenger RNA and protein expressions of transforming growth factor β-1 correlated positively with collagen type I volume fraction (r=0.723, P <0.001 and r=0.745, P <0.001, respectively) and left atrial dimension (r=0.762, P <0.001 and r=0.765, P <0.001, respectively). In the sinus rhythm-maintained subgroup, the patients who regained functional atrial contraction had lower messenger RNA and protein expression of transforming growth factor β-1 than did the patients who failed to retain such function (P <0.05).We conclude that the expression of transforming growth factor β-1 in the resected left atrial appendage affects the recurrence of atrial fibrillation and restoration of functional left atrial contraction after the radiofrequency modified maze procedure.

Quantification of left ventricular myocardial collagen system in children, young adults, and the elderly

Studies on the collagen system of the human myocardium are still limited compared to those on small laboratory animals. The aim of this work was to observe the collagen tissue of the myocardium of the human heart as a function of age. The types of collagen, as well as the density of collagen tissue and the diameter of collagen fibrils, were examined. Fragments of the left ventricular wall from 15 hearts, 5 from children, 5 from young adults, and 5 from elderly individuals, were analyzed by using the Picrosirius-polarization method and by transmission electron microscopy (TEM). The results showed the presence of collagen type III and collagen type I, both in the endomysium and perimysium of the 3 groups studied. Measurements of collagen content in myocardial tissue displayed that both endomysial and perimysial collagen increase in number and thickness in the adult and elderly. These histochemical results coincided with the observations obtained with the electron microscope in showing an increase in the number of collagen fibrils with a large diameter in the adult and elderly hearts. The present results on cardiac collagen may be important for assessing the pathogenesis of several cardiopathies in the hearts of children, young adults, and the elderly.

[Expression of matrix metalloproteinase-9 in myocardium of mice with viral myocarditis]

OBJECTIVE

To investigate the dynamic changes of expression of matrix metalloproteinases-9 in myocardium of mice with viral myocarditis (VMC) and its significance in the pathogenesis of viral myocarditis.

METHODS

VMC model was prepared by an injection of CVB3 in BALB/C mice. The mice receiving an injection of culture solution without virus were used as the control group. Cardiac tissues were obtained 7, 14, 21 and 28 days after injection and made into paraffin sections. Myocardial histopathologic changes were observed by hematoxylin-eosin staining and Masson staining. The expression of MMP-9, type I collagen and type III collagen in cardiac tissues were quantified by SABC immunohistochemical method.

RESULTS

The expression of MMP-9 in the VMC model group was observed on the 7th day, reached a peak on the 14th day, and was significantly higher than that in the control group at all time points (P<0.05). Compared with the control group, the expression of type I collagen in the VMC model group was up-regulated on the 21st day and reached a peak on the 28th day (P<0.05). The expression of type III collagen in the VMC model group was significantly higher than that in the control group on the 28th day (P<0.05). The expression of MMP-9 was positively correlated with myocardial histopathologic scores (r=0.832, P<0.05) and negatively correlated with type I collagen expression (r=-0.791, P<0.05).

CONCLUSIONS

MMP-9 is over-expressed at the early stage in VMC mice, and participates in the pathological process of VMC through mediating the degradation metabolism of type I collagen. It may be an important factor that leads to myocardial collagen remodeling and myocardial fibrosis.

Development and validation of an enzyme-linked immunosorbent assay for the quantification of a specific MMP-9 mediated degradation fragment of type III collagen--A novel biomarker of atherosclerotic plaque remodeling

OBJECTIVE

Degradation of collagen in the arterial wall by matrix metalloproteinases is the hallmark of atherosclerosis. We have developed an ELISA for the quantification of type III collagen degradation mediated by MMP-9 in urine.

DESIGN AND METHODS

A monoclonal antibody targeting a specific MMP-9 generated fragment of collagen III was used in a competitive ELISA. The assay was validated in urine and arterial tissue of Apolipoprotein-E knockout (ApoE-KO) mice.

RESULTS

The lower limit of detection was 0.5ng/mL, intra- and inter-assay coefficients of variation were below 10%. By the end of 20weeks of the study, urine levels of the novel CO3-610 biomarker in ApoE-KO mice increased by two-fold (p<0.0001) and were three-fold higher than in control mice. Western blots confirmed high expression of CO3-610 in arterial extracts of ApoE-KO mice.

CONCLUSION

We have developed a novel competitive ELISA, capable of measuring a urine biomarker indicative of pathological extracellular matrix remodeling in a mouse model of atherosclerosis.

Effects of valsartan on diabetic cardiomyopathy in rats with type 2 diabetes mellitus

BACKGROUND

The development of diabetic cardiomyopathy is multifactorial. Insulin resistance (IR) and excessive activity of the renin-angiotensin system are confirmed reasons for diabetic cardiomyopathy. Renin-angiotensin system (RAS) inhibitors can reduce tissue Ang II levels, with beneficial effects on cardiovascular function. Therefore, in type-2 diabetes mellitus (T2DM), blockade of the RAS may have the function of protecting against diabetic cardiomyopathy through increasing insulin sensitivity and inhibiting excessive activity of RAS. However, this has not been confirmed.

METHODS

The effect of valsartan, an angiotensin receptor blocker (ARB), on diabetic cardiomyopathy in the presence of T2DM was studied. Wistar rats with T2DM and T2DM treated with valsartan were studied. Glucose infusion rates (GIR), index of IR, heart weight, the heart weight-to-body weight ratio (HW/BW), myocardial apoptotic index, cardiac hydroxyprolin content, and cardiac tissue collagen type I and collagen type III content were measured.

RESULTS

GIR in T2DM rats and T2DM rats treated with valsartan decreased (P < 0.01). In T2DM rats treated with valsartan, heart weight, myocardial apoptotic index, cardiac hydroxyprolin content, and cardiac tissue collagen type I and collagen type III content were higher than in control rats, but lower than in T2DM rats. In rats with T2DM, GIR was negatively and significantly correlated with all the variables. However, in T2DM rats treated with valsartan or normal control rats, none of the correlations was significant.

CONCLUSIONS

In the presence of T2DM, diabetic cardiomyopathy is related with IR. Valsartan can not alleviate IR, but can protect against diabetic cardiomyopathy and remove the correlation between IR and diabetic cardiomyopathy.

Electrical stimulation inhibits neointimal hyperplasia after abdominal aorta balloon injury through the PTEN/p27Kip1 pathway

Electric fields (EFs) exert biological effects on promoting wound healing by facilitating cell division, cell proliferation, and cell directional migration toward the wound. In this study, we examined the inhibitory effect of direct-current (DC) EFs on the formation of neointimal hyperplasia and the possible mechanism in an abdominal aorta balloon injury rabbit model. Sixty rabbits were divided into normal, control, and experimental groups. After establishment of the abdominal aorta balloon injury model, electrodes were implanted into the bilateral psoas major muscle in control and experimental groups. Only the experimental group received electric stimulation (EFs applied at 3 or 4 V/cm for 30 min/day) for 1, 2, and 4 weeks, respectively. Neointimal hyperplasia of the abdominal aorta and proliferation of vascular smooth muscle cells (VSMCs) were measured. Expressions of collagen, p27(Kip1), and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) were detected. Results showed that the ratio of the tunica intima area to the tunica media area, the expression of type-I collagen in the neointimal, and the proliferating cell nuclear antigen index in experimental groups were significantly less than those in control groups 2 weeks post-operation (P< 0.01). Expressions of p27(Kip1) and PTEN were increased in experimental groups compared with control groups (P< 0.01). In conclusion, our results suggested that the application of DC EFs could inhibit neointimal hyperplasia and reduce collagen expression after abdominal aorta balloon injury. This was probably induced by upregulation of PTEN/p27(Kip1) expression, thereby inhibiting VSMC proliferation.

[THE ROLE OF SERUM COLLAGEN TYPE III AUTOANTIBODIES AND STRUCTURAL AND OPTICAL PROPERTIES IN THE EVALUATION OF REPARATIVE PROCESSES IN CHILDREN WITH TUBERCULOSIS]

The paper gives the results of an original study of the morphological pattern of serum elementary association along with ELISA determination of collagen type III autoantibody levels in the sera of 84 children with active pulmonary tuberculosis and 25 children from risk groups as shown by the data of tuberculin diagnosis. There is evidence that a package of these methods is highly effective in evaluating lung tissue reparative processes in children with pulmonary tuberculosis. The proposed original analysis matrix that permits the outcome of the specific process to be predicted from the concentration of collagen type III autoantibodies and the type of leaf-shaped structures is promising for use at specialized facilities.

Detection of V, III and I type collagens of dermal tissues in skin lesions of patients with systemic sclerosis and its implication

This study investigated the contents and distribution of collagen V (Col V) in skin lesions of the patients with systemic sclerosis (SSc) and its roles in the pathogenesis. The contents and distribution for alpha1 chain of collagen type I, III and V [alpha1 (I), alpha1 (III) and alpha1 (V)] in skin lesions of 36 patients with SSc (9 cases of mild fibrosis, 14 moderate, and 13 severe) were detected by using immunohistochemical SP method. Six cases of normal skin tissues served as controls. The results showed that there was diffuse distribution for three kinds of collagens in dermis. The deep staining alpha1 (I) and alpha1 (III) masses or bands were seen in reticular layer, while alpha1 (V) was distributed more homogeneously. From control to weak, moderate and severe fibrosis stages, alpha1 (I), alpha1 (III) and alpha1 (V) showed a gradually increased trend in skin lesions (P<0.05). alpha1 (V) was obviously elevated in skin lesions at early stage and persisted in whole fibrotic process and risen in greater contents, while alpha1 (I) and alpha1 (III) were to go higher late and were apparently elevated at moderate and late stages. Compared with alpha1 (I), alpha1 (V) took leading increase at early stage in skin lesions (P<0.01), and had more elevated contents than alpha1 (III) at moderate and late stages. The fibrotic changes in dermal reticular layer occurred earlier than those in papillary layer, and the abnormalities of alpha1 (V)/alpha1 (I) ratio appeared before alpha1 (III)/alpha1 (I) ratio. It was concluded that a lot of alpha1 (V) began to deposit in greater contents prior to alpha1 (I) and alpha1 (III) at early stage in SSc and persisted in whole fibrotic process. The changes of alpha1 (V) contents in reticular layer occurred earlier than those in papillary layer, and it suggested that the fibrosis in reticular layer appeared earlier.

Role of connective tissue growth factor in experimental radiation nephropathy in rats

BACKGROUND

Connective tissue growth factor (CTGF) is a potent fibrogenic cytokine which has been associated with progressive glomerulosclerosis and tubulointerstitial fibrosis. We investigated the role of CTGF on the progression of a rat model of radiation nephropathy.

METHODS

The model of radiation nephropathy in rats was established as follows: control group (n = 12), underwent only laparotomy; irradiated group (n = 20), underwent a laparotomy, then the rats were subjected to a single dose 25 Gy X-ray to the kidneys. The rats were followed up one, three, six and nine months after renal exposure to radiation.

RESULTS

Renal dysfunction was noted early in irradiated rats. Histological analysis showed focal glomerular sclerotic lesions at an early stage after irradiation. Radiation-induced glomerular and tubulointerstitial injuries were particularly severe the sixth month after irradiation as compared to the control group (P < 0.01). By immunohistochemistry, increased expression of CTGF was noted in the irradiated kidneys, which began to increase from the first month after irradiation, and remained significantly higher at the sixth and ninth month after irradiation (P < 0.01). Upon Western blot analysis CTGF protein expression showed an increase in the radiation treated kidneys compared with the control rats. The expression of CTGF closely correlated with the progression of radiation nephropathy. The expression of alpha-smooth muscle actin, vimentin, type III collagen and type IV collagen was also high in the irradiated kidney as compared to control rat kidneys (P < 0.05), and was most severe at the sixth and ninth month after irradiation (P < 0.01). By double immunostaining, CTGF expressing cells were found to be alpha-SMA-positive myofibroblasts and vimentin-positive tubular epithelial cells. Glomerular expression of CTGF closely correlated with the glomerular expression of alpha-SMA (r = 0.628, P < 0.01), vimentin (r = 0.462, P < 0.05) and accumulation of type IV collagen (r = 0.584, P < 0.01) in the irradiated kidney. Similarly, the expression of CTGF was positively correlated with the expression of alpha-SMA (r = 0.613, P < 0.01), vimentin (r = 0.629, P < 0.01), deposition of type III collagen (r = 0.741, P < 0.001) and type IV collagen (r = 0.799, P < 0.0001) in the tubulointerstitium of the irradiated kidney. Finally the expression of CTGF after the irradiation of the kidney positively correlated with the levels of blood urea nitrogen and serum creatinine.

CONCLUSION

Overexpression of CTGF may play an important role in the development and progression of glomerulosclerosis and tubulointerstitial fibrosis in radiation nephropathy.

[Expression of COL1a1 and COL3a1 in the capsule of children with developmental dislocation of the hip]

OBJECTIVE

The etiology of developmental dislocation of the hip (DDH) remains uncertain, but some research has shown that this disorder is closely related to hip joint laxity. This study examined the expression of collagens type I and III mRNA and protein in the hip capsule of children with DDH in order to investigate the roles of collagens type I and III in hip joint laxity.

METHODS

Nine children with DDH and nine age and gender-matched normal children (control group) were enrolled. Semiquantitative RT-PCR method was used to detect mRNA expression of COL1a1 and COL3a1 in the hip capsule. Western-Blot method was used to detect protein expression of COL1a1 and COL3a1 in the hip capsule. The quantitative analysis of the COL1a1 and COL3a1 was performed by professional image software and the results were analyzed with standard statistical methods.

RESULTS

mRNA and protein expression of COL1a1 in the DDH group was significantly lower than that in the control group (P<0.01). Compared with the control group, COL1a3 mRNA expression in the DDH group decreased significantly (P<0.01), but COL1a3 protein expression was not significantly different.

CONCLUSIONS

The decreased collagen I mRNA and protein expression in the hip capsule might contribute to hip joint laxity in children with DDH. Collagen type III may not be associated with hip joint laxity in DDH.

[An autopsy specimen study of benign hyperplastic nodules in the peripheral zone of the prostate]

OBJECTIVE

To investigate the correlation and anatomic association of benign hyperplastic nodules in the peripheral zone (PZ) with those in the transition zone (TZ) of the prostate, and to compare the histological components of the two kinds of nodules.

METHODS

We obtained benign hyperplastic nodules specimens from the PZ and TZ by autopsy, measured the distance between the outer surface of the nodules and the inner gland, observed the integrity of the surgical envelope of the prostate, and determined the histological components of the two kinds of nodules by HE staining, immunohistochemistry and automatic quantitative image analysis.

RESULTS

The surgical envelope of the prostate was integrated and the distance between the nodules of the PZ and the outer surface of the inner gland was about 2.5 to 5 mm ([3.9 +/- 0.8] mm), with no signs of anatomic connection in between. The stromata and epithelia in the nodules accounted for (69.32 +/- 8.35)% and (16.08 +/- 5.36)% in the PZ and (74.58 +/- 8.95)% and (15.82 +/- 6.41)% in the TZ.

CONCLUSION

Benign hyperplastic nodules may originate from the PZ of the prostate and not correlate with the inner gland hyperplasia in the TZ, but with no statistical difference between the histological components of the two kinds of nodules.

[Quantification of type I and III collagen content in normal human skin in different age groups]

OBJECTIVE

To quantify the content of type I, III collagen and their ratio in normal human skin of different age, and to explore the regulation of changes.

METHODS

The normal human skin specimens were obtained from 6 spontaneously aborted fetus and 56 burn patients of different ages, including infants (newborn -3 years), pre-school group ( > 3, < or =7 years), adolescent group ( >7, < or = 18 years), youth and middle age group ( > 18, < or = 50 years), and elderly group ( > 50 years), were studied. The total collagen content were determined by hydroxyproline method. The contents of type I, Ill collagen and their ratio were examined by immunohistochemistry.

RESULTS

The total collagen content decreased along with increase in age, and it was highest in fetus [(543 +/- 13) microg/g]. The ratio between type I and Ill collagen increased along with increase in age. The content of type III collagen was highest in fetus [(278 +/- 7) microg/g], and it decreased along with increase in age. The content of type I collagen content was [(265 +/- 7) microg/g] in fetus, and it was increased slightly in infant and pre-school groups, then decreased along with advance in age.

CONCLUSION

Decomposition of type III collagen in normal human skin may exceed its synthesis after birth immediately, leading to its reduction. Synthesis of type I collagen in normal human skin is dominant before 8 years old, and it shows an opposite tendency afterwards.

Comparison of collagen subtype I and III presence in varicose and non-varicose vein walls

STUDY OBJECTIVES

The connective tissue alterations in varicose vein wall are supposed to be one of the main causes of primary varicose vein (main sign of human lower limbs chronic venous insufficency).

METHODS

5 varicose vein samples from 5 patients undergoing stripping surgery of long saphenous vein were compared with 5 control samples of healthy (non-dilated) long saphenous veins from necroptic material (with no history of varicosis). They were fixed in a Baker solution, processed by use of light microscopic method, cut to ultra-thin sections (4-5 microm) and stained with PicroSirius Red for collagen. Sections were scanned with light microscope (Leica, Germany) and camera Canon S50 (Germany) and analysed by morphometric programme Image J v.1.38g (National Institute of Health, USA).

RESULTS

In the group of healthy (non-dilated) veins the mean collagen I/III ratio value was 31.40 and in the group of varicose veins the mean collagen I/III ratio was 12.35; the difference is statistically significant: healthy veins contain significantly more of collagen subtype I and varicose veins contain significantly more of collagen subtype III in their walls.

CONCLUSION

The statistically significant difference in the collagen I/III ratio between the groups of healthy (non-dilated) and varicose (dilated) vein walls is worthy of further following (Tab. 2, Fig. 7, Ref. 12). Full Text (Free, PDF) www.bmj.sk.

Enhanced alpha 1(I) mRNA expression in frozen shoulder and dupuytren tissue

The purpose of this study has been to investigate collagen I and III synthesis during the fibrosing stage of frozen shoulder and Dupuytren samples in comparison to normal capsule tissue. - By using the quantitative PCR significantly increased levels of alpha 1(I) mRNA transcription in samples of frozen shoulder (p = 0.016) and Duypuytren (p = 0.041) could be demonstrated, whereas alpha 2(I) and alpha 1(III) chains have shown the same mRNA levels as in normal capsule tissue. - Despite an enhancement of alpha 1(I) mRNA transcription in frozen shoulder and Dupuytren samples the intracellular precursor procollagen I and extracellular mature collagen I was detected immunohistochemically in reduced levels. - The structural alteration of collagen I assembly might be caused by disturbed post-translation from the polypeptide chains into the triple helices procollagen I though alpha 1(I) mRNA transcription was significantly increased and alpha 2(I) mRNA transcription was in normal range. Fibroblasts might release high quantities of free alpha 1(I) polypeptide chains or (alpha 1(I)) 3 homotrimer into the extracellular space during the fibrosing stage of frozen shoulder and Dupuytren disease. - In all samples neither differences of alpha 1(III) mRNA transcription nor differences of immunohistochemical staining intensity of collagen III could be seen. This might result from apoptosis of myofibroblasts in the final phase of the fibrosing processes. - The stimulating effect of insulin-like growth factor type I (IGF-I) to induce fibrosis in connective tissue such as scarlet is known. In all patients suffering from frozen shoulder and Dupuytren disease the serum IGF-I level was in a normal range and the IGF-I receptor - (IGFR-I) mRNA transcription in the samples was also in the same level compared with normal capsule tissue.

[Effects of Feixianping on collagen type I and III in bleomycin induced pulmonary fibrosis rats]

OBJECTIVE

To study the effect of Feixianping (FXP) on collagen type I and II in rats with pulmonary fibrosis (PF).

METHODS

Sixty healthy male SD rats were randomly divided into 5 groups, the normal group (A), the model group (B), the positive control group (C) and the two FXP groups (D and E) treated respectively with high and low dose of FXP. Except those in Group A (they were not modeled and administered with normal saline), all rats were established into PF model by intra-tracheal instillation of bleomycin and administered with respective medicines starting from the 1st day after modeling. Rats were sacrificed in batches at 3 time points, the 7th, 14th, and 28th day for observing the pathological changes of lung under light microscope with HE staining and to identify collagen type I and III in lung tissue by immunohistochemical stain and image quantitative analysis.

RESULTS

Light-dyeing proliferative collagen fiber was presented in the slightly thickened alveolar wall in lung of modeled rats from the 14th day on, and the pathological changes became more distinct on the 28th day. The highest amount of collagen appeared in the group B, correspondingly, that in all the other groups was much lower (P < 0.05). Reduction of collagen type I and III revealed in both FXP treated groups, but better effect was shown in the high dose FXP group. The effect of FXP was superior to that of positive control on the 14 th day (P <0.05).

CONCLUSION

FXP can effectively reduce the abnormal proliferation of collagen in experimental rats with PF.

Down-regulation of TGFbeta1 and leptin ameliorates thioacetamide-induced liver injury in lipopolysaccharide-primed rats

Pretreatment with a low dose of bacterial endotoxin (lipopolysaccharide, LPS) caused the reduction of cytochrome P450 (CYP) enzymes and inflammatory factors which are capable of protecting the liver from a lethal LPS challenge. However, the effects of LPS pretreatment on the expression of transforming growth factor beta1 (TGFbeta1) and leptin in thioacetamide (TAA)-induced liver fibrosis remain unknown. In this study, Sprague-Dawley rats were pretreated intraperitoneally with LPS (5 mg/kg body weight) for 24 h, and subsequently treated with TAA (200 mg/kg body weight/ 3 days) for 1 month to examine the effects of LPS on TAA-injured rats. LPS pretreatment was associated with lower granulation and lower (P < 0.05) GOT/GPT than in TAA-injured rats. The LPS-pretreated group had less collagen (Sirius red histochemical staining). Semiquantitative RT-PCR showed that the levels of collagen 3 and TGFbeta1 mRNAs were lower (P < 0.05) in the liver of LPS-pretreated rats than in TAA-injured rats. TGFbetaRI mRNA in the liver of LPS-pretreated rats exceeded (P < 0.05) that in TAA-injured rats. LPS pretreatment reduced the leptin content (Western blot) below that of TAA-injured rats. These results imply that LPS pretreatment (endotoxin tolerance) alleviates the TAA-induced liver fibrosis of rats by reducing TGFbeta1 and leptin content.

The evolution of collagen expression in sarcomatoid renal cell carcinoma

The development of a sarcomatoid morphotype is recognized as an extreme form of dedifferentiation in renal cell carcinoma and is associated with a poor prognosis. Although sarcomatoid renal cell carcinoma shows pronounced spindle cell morphology, clear cell renal cell carcinoma may show early spindle cell change with cellular elongation, and the prognostic significance of this is debated. To determine the relationship between sarcomatoid renal cell carcinoma and clear cell renal cell carcinoma showing early spindle cell change, we have investigated collagen expression using immunohistochemistry in these 2 tumor types. Both sarcomatoid renal cell carcinoma and early spindle cell change tumors showed pericellular interstitial expression of collagen types I and III, whereas sarcomatoid renal cell carcinoma also showed cytoplasmic expression of these collagen types. Expression of these collagen types in typical clear cell renal cell carcinoma was, in occasional cases, limited to faint and patchy staining in a pericellular interstitial distribution. Tumor cells did not stain for collagen type IV in sarcomatoid renal cell carcinoma, early spindle cell change, or typical clear cell renal cell carcinoma. In sarcomatoid renal cell carcinoma, there was diffuse pericellular expression of collagen type V and patchy pericellular expression of collagen type VI, whereas early spindle cell change tumors showed patchy pericellular staining with antibodies to collagen type V. Collagen type VI expression in early spindle cell change was largely confined to the vascular adventitia and areas of scarring, although very occasional foci of faint interstitial staining were also seen. In typical clear cell renal cell carcinoma, staining of collagen types V and VI was limited to the vascular adventitia and foci of desmoplasia, whereas no staining of tumor cell cytoplasm were seen. This study has shown that collagen expression of sarcomatoid renal cell carcinoma differs from that of early spindle cell change and provides validating evidence that these 2 morphotypes should not be considered together for classification purposes.

Extracellular matrix expression and periodontal wound-healing dynamics following guided tissue regeneration therapy in canine furcation defects

AIM

Temporal and spatial expression pattern of extracellular matrix (ECM) components in furcation defects following guided tissue regeneration (GTR) compared with open-flap debridement (OFD).

MATERIAL AND METHODS

In 21 dogs, mandibular second and fourth pre-molars were treated with one non-resorbable and three different resorbable membranes. Third pre-molars were treated by OFD. After 2, 4, 8 weeks and 3, 6, and 12 months, tissues were analysed by immunohistochemistry for collagen I (Col-I) and III (Col-III), fibronectin (FN), bone sialoprotein (BSP), and osteopontin (OPN).

RESULTS

At 2 weeks, the defect was mainly occupied by FN+ granulation tissue (GT), which was sequentially replaced by new connective tissue expressing FN, Col-I, and increasingly Col-III. Following superficial resorptions by OPN+ osteoclasts and odontoclasts, cementum and bone formation ensued with strong expression of BSP and OPN along bone and tooth surfaces. Deposition of Col-I, FN, BSP and OPN+ cementoid and osteoid became evident after 4 weeks. Extrinsic fibres of cementum and bone stained intensely for Col-III. The newly formed periodontal ligament expressed FN, Col-I, and Col-III, but no BSP or OPN.

CONCLUSIONS

The spatial ECM expression was similar for OFD and the different GTR methods, although the timing and quantity of ECM expression were influenced by wound stabilization and inflammatory reactions.

Morphology, quality, and composition in mature human peritoneal adhesions

BACKGROUND AND AIM

Peritoneal adhesions are caused by intra-abdominal surgery and can lead to relevant complications. Adhesions are supposed to consist of avascular scar tissue. The aim of the present study was to analyze whether mature postsurgical adhesions even after years still reveal a dynamic remodeling process.

MATERIALS AND METHODS

In a prospective analysis, we investigated tissue specimen of peritoneal adhesions in 40 patients after abdominal surgery. Expression of five parameters representing wound healing and remodeling were examined (MMP-2, Ki-67, apoptosis, collagen/protein ratio, and collagen type I/III ratio).

RESULTS

Gender, age, and the number of previous operations had no impact on the parameters measured. Adhesion specimens were cell rich, containing mononuclear round cells, fibroblasts, adipose cells, and vascular endothelial cells. There was a positive expression of MMP-2 and apoptosis, whereas Ki-67 was marginal irrespective of adhesion maturity or quality. Adhesions classified as dense showed a significant increase in total collagen (118.2 +/- 4.9 microg/mg) and collagen type I/III ratios (3.9 +/- 0.2), whereas there were no significant differences regarding the adhesion maturity.

CONCLUSION

The distinct composition of cellular components as well as of extracellular matrix proteins may reflect an interactive cross-talk between adhesion- and stroma-derived cells even in mature adhesions. Our findings support the hypothesis that the disabilities of appropriate repair of the peritoneal surface leading to persistent adhesions are a consequence of a permanent process of disturbed remodeling.

Immunohistochemical identification of type I and type III collagen and chondroitin sulphate in human pre-dentine: a correlative FEI-SEM/TEM study

AIM

To identify type I- (I-CF) and type III-collagen fibrils (III-CF) and chondroitin 4/6 sulphate (CS) within human pre-dentine by means of a correlative analysis under field emission in-lens-scanning electron microscopy (FEI-SEM) and transmission electron microscopy (TEM).

METHODOLOGY

Human-extracted teeth were obtained and submitted to either a pre-embedding or a post-embedding immunolabelling procedure using monoclonal primary antibodies anti-I-CF, anti-III-CF and anti-CS. Gold-conjugated secondary antibodies were coupled to primary antibodies to visualize labelling under the electron beam. Correlative labelling patterns were obtained for I-CF and CS under both FEI-SEM and TEM.

RESULTS

Field emission in lens-SEM analysis revealed an intricate three-dimensional network of I-CF and CS clarifying the intimate relationship between the two main components of the pre-dentine organic matrix. TEM analysis revealed odontoblasts exhibiting intracellular labelling for CS, which became more intense and diffuse over the pre-dentine organic matrix. The same diffuse immunoreaction was revealed for I-CF, whereas a weak immunolocalization of III-CF was found scattered throughout the pre-dentine layer and over the collagen fibrils.

CONCLUSIONS

Both the pre- and post-embedding immunohistochemical approaches have led to the visualization of CF- and CS-labelling distribution within the pre-dentine layer, adding further knowledge on the elucidation of collagen-proteoglycans interaction in the organic matrix of human dental roots.

Role of biomarkers in incisional hernias

Incisional hernias represent one of the most common complications of laparotomies. Previous investigations have suggested that a disorder in collagen fiber structure and production level may be an important pathologic cause of abdominal wall hernias. We hypothesized that a cross-examination of multiple extracellular matrix biomarkers might identify underlying defects contributing to the development of hernias. We examined two patient populations: patients with incisional hernias (presenting for hernia repair) and patients with no hernia after previous laparotomy (undergoing a second laparotomy). Patients with previous wound infections, open abdomens, or on steroids were excluded. Fascia samples were obtained from all patients at the time of their second operation and they were studied. Western blots and reverse transcriptase-polymerase chain reaction were used to determine the ratio of type I, III, and IV collagens, as well as matrix metalloproteinase 1 (MMP1) and MMP2 in both groups. Values of P < 0.05 were considered statistically significant. At the protein level, collagen I/III ratio was slightly decreased in patients with incisional hernias compared with those with no hernia, whereas it was significantly decreased at the mRNA transcript level (0.49 vs 1.03, P < 0.01, respectively). The MMP-1 mRNA transcripts were not different in incisional hernia (IH) versus nonincisional hernia, but the MMP-2 level was significantly increased in patients with IH. Reduced collagen I/III and MMP-1/MMP-2 ratios in IH might be consequence of the biological activities between key elements participating in the development of IH after laparotomies. The potential role of MMP-2-specific inhibitors in preventing IH is of significance for future studies.

[Effects of rejuvenation by intense pulsed light and basic mechanism thereof]

OBJECTIVE

To evaluate the effects of rejuvenation by intense pulsed light (IPL) and the mechanism thereof.

METHODS

Fifty-eight patients with photo aging were treated with IPL of single, double, or triple pulse pattern for 3 - 5 times with the intervals of 3 - 4 weeks. Three weeks after the last treatment, photography was conducted and the pictures underwent grading by the physicians and patients according to blind method. Skin specimens of the posteroinferior ear lobe or the nape were obtained from 4 patients to undergo HE staining, Uana orcein staining of elastin, immunohistochemical staining for collagenous fibers of types I and III, and transmission electron microscopy was conducted in 2 of the 4 patients. Skin digitalized image analysis was conducted on 34 female patients to measure and analyze the depth and width of dermatographs, roughness of skin.

RESULTS

After the third treatment, the wrinkles and skin texture of 62.1% of the patients showed improvement, and 84.60% of the pigmented lesions and 81.25% of the vascular lesions showed improvement. Pathology showed that type I and type III collagen increased while elastin decreased, and the fibers were orderly re-arranged. Transmission electron microscopy showed that after treatment the fibroblasts increased in number and became more active in secretion and there were more collagen fibers orderly re-arranged in the stroma. Digitalized image analysis showed significant improvement in skin smoothness, depth, arithmetic average roughness and average roughness of skin texture (all P < 0.01).

CONCLUSION

IPL is effective to improve the skin texture. The mechanism may be the increasing of the activity of the fibroblasts, and hyperplasia and re-arrangement of collagen and elastin.

An immunohistochemical study of the triangular fibrocartilage complex of the wrist: regional variations in cartilage phenotype

The triangular fibrocartilage complex (TFCC) transmits load from the wrist to the ulna and stabilizes the distal radioulnar joint. Damage to it is a major cause of wrist pain. Although its basic structure is well established, little is known of its molecular composition. We have analysed the immunohistochemical labelling pattern of the extracellular matrix of the articular disc and the meniscal homologue of the TFCC in nine elderly individuals (age range 69-96 years), using a panel of monoclonal antibodies directed against collagens, glycosaminoglycans, proteoglycans and cartilage oligomeric matrix protein (COMP). Although many of the molecules (types I, III and VI collagen, chondroitin 4 sulphate, dermatan sulphate and keratan sulphate, the oversulphated epitope of chondroitin 6 sulphate, versican and COMP) were found in all parts of the TFCC, aggrecan, link protein and type II collagen were restricted to the articular disc and to entheses. They were thus not a feature of the meniscal homologue. The shift in tissue phenotype within the TFCC, from a fibrocartilaginous articular disc to a more fibrous meniscal homologue, correlates with biomechanical data suggesting that the radial region is stiff and subject to considerable stress concentration. The presence of aggrecan, link protein and type II collagen in the articular disc could explain why the TFCC is destroyed in rheumatoid arthritis, given that it has been suggested that autoimmunity to these antigens results in the destruction of articular cartilage. The differential distribution of aggrecan within the TFCC is likely to be reflected by regional differences in water content and mobility on the radial and ulnar side. This needs to be taken into account in the design of improved MRI protocols for visualizing this ulnocarpal complex of the wrist.

Gas-related impact of pneumoperitoneum on systemic wound healing

INTRODUCTION

The aim of the present study was to investigate the gas-dependent effects of pneumoperitoneum on wound healing distant from the abdomen.

MATERIALS AND METHODS

Dorsal skin incisions were performed in 54 male Sprague-Dawley rats. A CO(2) or a helium pneumoperitoneum of 3 mmHg was maintained before, with an overall duration of 30 min (each n = 18). Rats in the control group received laparotomy only (n = 18). Animals were killed after 5 and 10 days. The infiltration of macrophages (CD 68), expression of matrix metalloproteinase 13 (MMP-13) and collagen I/III ratios were analysed in the dorsal skin wounds.

RESULTS

Both after 5 and 10 days, infiltration of macrophages and expression of MMP-13 were greatest after helium pneumoperitoneum. After 5 days, collagen I/III ratio was significantly increased in the helium group. After 10 days, collagen I/III ratio was lowest in the CO(2) group.

CONCLUSION

Our results suggest beneficial effects on systemic wound healing for helium pneumoperitoneum as compared to CO(2).

Alteration of knee joint connective tissues during contracture formation in spastic rats after an experimentally induced spinal cord injury

This study was made to elucidate the changes in the periarticular connective tissue that can underlie the contracture after spasticity development. Sixteen Wistar rats underwent a spinal cord injury and 16 rats were either sham- or nonoperated. The periarticular connective tissue of the knee joint was assessed with histological, histomorphometric, immunohistochemical, and biochemical analyses. Histological results showed a smaller synovial intima, a dense subintimal and posterior joint capsule without fibrosis, and a disarranged posterior capsule in the spinal cord-injured knees with the flexion contracture. The synovial intima length was shortened only at the posterior capsule. Neither the distribution nor expression of type I and III collagen was affected. Contractures after spinal cord injuries are characterized by synovial intima adhesions. A dense and disarranged capsule may lead to joint stiffness. The alteration of periarticular connective tissues exhibits properties characteristic of the contracture after spasticity development.

Endostatin peptide, an inhibitor of angiogenesis, prevents the progression of peritoneal sclerosis in a mouse experimental model

Peritoneal sclerosis is a major and serious complication in patients on long-term continuous ambulatory peritoneal dialysis (PD). The involvement of angiogenesis and proangiogenic factors such as vascular endothelial growth factor (VEGF)-A in progressing peritoneal sclerosis has been reported. We previously reported the therapeutic efficacy of endostatin peptide, a potent inhibitor of angiogenesis derived from type XVIII collagen, in a mouse diabetic nephropathy model. Here, we examined the therapeutic effect of endostatin peptide in preventing progression in a mouse peritoneal sclerosis model. Male ICR mice received intraperitoneal injections of chlorhexidine gluconate (CG) every other day to induce peritoneal sclerosis. Endostatin peptide (1 or 4 mg/kg/day) was administered via subcutaneously implanted osmotic minipumps. Peritoneal sclerosis (day 24) was significantly suppressed by endostatin peptide in a dose-dependent manner. Peritoneal accumulation of type III collagen was significantly suppressed by endostatin peptide. Increase in the number of CD31(+) blood vessels, F4/80(+) monocyte/macrophage accumulation, and 5-bromodeoxyuridine(+) proliferating cells was significantly inhibited by endostatin peptide. Increase in peritoneal expression of VEGF-A, profibrotic transforming growth factor-beta1, and alpha-smooth muscle actin was suppressed by endostatin peptide. Immunoreactivity for endogenous endostatin (whole molecule) and endostatin receptor alpha5beta1-integrin was increased and colocalized to CD31(+) blood vessels in the thickened peritonea of CG-injected mice. These results demonstrate the potential use of antiangiogenic endostatin peptide as a novel therapeutic agent in preventing peritoneal sclerosis, a severe complication in patients undergoing long-term PD.