New in vivo model to assess macroscopic, histological, and molecular changes in Peyronie's disease.

BACKGROUND: Peyronie's Disease (PD) is a connective tissue disorder that affects the tunica albuginea (TA) of the penis causing curvature and erectile dysfunction. The pathophysiology is not well understood and, for this reason, treatment options are limited. OBJECTIVE: The aim of the present study is to analyze and compare whether single or multiple instillations of plasma in the TA of rats is capable of triggering macroscopic, histopathological, and molecular changes consistent with PD. MATERIAL/METHODS: Fifty male Wistar rats were divided into four groups: Group 1: a single instillation of plasma in the TA; Group 2: a single instillation of distilled water in the TA; Group 3: four instillations of plasma in the TA (1x per week); and Group 4: four instillations of distilled water in the TA (1× per week). Forty-five days after the last instillation a manual inspection of the corpus cavernosum, a penile erection test and a penectomy were performed to obtain material for histopathological and molecular analysis. RESULTS: It was observed that 31.25% of the rats that received repeated instillations of plasma presented penile curvature according to the erection test, while none of the rats from the control group or group with one instillation of plasma presented curvature. In the animals that received four instillations of plasma, the following differences were observed in relation to the control group: increase in fibrosis and the deposition of collagen I. The protein expression of heparanase (HPSE) and TGF-ß increased in the groups that received a single or four instillations of plasma, and the protein expression of heparanase-2 (HPSE-2), metalloproteinases (MMP-2, MMP-9) and metalloproteinase inhibitor (TIMP-2) showed an increase in the group that received four instillations of plasma. There was a significant increase in the gene expression of HPSE, MMP-9, and TGF-ß in the group that received four instillations of plasma. In the analysis of the glycosaminoglycans, an increase was observed in the secretion of galactosaminoglycans chondroitin sulfate and dermatan sulfate (CS/DS) in the group that received four instillations of plasma. DISCUSSION: Previous studies have demonstrated increased protein expression. of HPSE, MMP-9 and TGF-ß with instillation of blood in the TA; however, there was no increase in gene expression. In the present study, the increase in the expression of TGF-ß with plasma instillations, proved to be more reliable. The two models with plasma (one or four instillations) demonstrated significant histopathological and molecular changes when compared to the control group. However, only in the group with four plasma instillations there was a macroscopic change. The idea is that repeatedly extravasation of TGF-ß present in plasma of predisposed individuals acts as a trigger for the development and maintenance of changes in the extracellular matrix that perpetuate an anomalous inflammatory process present in PD. CONCLUSION: The present study shows that the repeated instillation of plasma is a low cost in vivo model for the study of PD.

Extracellular matrix alterations after blood instillation in tunica albuginea of rats.

The cause of Peyronie's disease (PD) is still not completely understood. The objective of this study, therefore, was to analyze the histological and biochemical alterations that occur after the instillation of blood in the tunica albuginea (TA) of rats with an emphasis on the remodeling process of ECM. Thirty male Wistar rats were divided into 4 groups: two control groups with instillation of distilled water in TA followed by penectomy after 15 days or 45 days, respectively and two experimental groups with instillation of blood in TA followed by penectomy after 15 days or 45 days, respectively. Histological, immunofluorescent and immunohistochemical analyses were performed. The higher presence of fibrotic tissue in rats injected with blood demonstrated alterations in TA similar to inflammation found in PD. The increased expression of TGF-ß, MMP9, HPSE, and biglycan associated with the decreased expression of syndecan-1 and aggrecan in the experimental groups suggested an enhancement in the remodeling of ECM. The results contribute to show that blood instillation on TA appears to trigger alterations in the ECM similar to the ones found in inflammatory diseases such as PD.

Colorectal cancer desmoplastic reaction up-regulates collagen synthesis and restricts cancer cell invasion.

During cancer cell growth many tumors exhibit various grades of desmoplasia, unorganized production of fibrous or connective tissue, composed mainly of collagen fibers and myofibroblasts. The accumulation of an extracellular matrix (ECM) surrounding tumors directly affects cancer cell proliferation, migration and spread; therefore the study of desmoplasia is of vital importance. Stromal fibroblasts surrounding tumors are activated to myofibroblasts and become the primary producers of ECM during desmoplasia. The composition, density and organization of this ECM accumulation play a major role on the influence desmoplasia has upon tumor cells. In this study, we analyzed desmoplasia in vivo in human colorectal carcinoma tissue, detecting an up-regulation of collagen I, collagen IV and collagen V in human colorectal cancer desmoplastic reaction. These components were then analyzed in vitro co-cultivating colorectal cancer cells (Caco-2 and HCT116) and fibroblasts utilizing various co-culture techniques. Our findings demonstrate that direct cell-cell contact between fibroblasts and colorectal cancer cells evokes an increase in ECM density, composed of unorganized collagens (I, III, IV and V) and proteoglycans (biglycan, fibromodulin, perlecan and versican). The desmoplastic collagen fibers were thick, with an altered orientation, as well as deposited as bundles. This increased ECM density inhibited the migration and invasion of the colorectal tumor cells in both 2D and 3D co-culture systems. Therefore this study sheds light on a possible restricting role desmoplasia could play in colorectal cancer invasion.

Antral exfoliative cytology for the detection of Helicobacter pylori in the stomach.

AIM: To evaluate the efficacy of antral exfoliative cytology method in the diagnosis of Helicobacter pylori (H pylori) infection in the stomach. METHODS: Fifty patients were submitted to upper digestive tract endoscopy due to complaints of dyspepsia. The material for exfoliative cytology was obtained by extensive brushing of the gastric antral mucosa and Papanicolaou stain was used to identify the bacteria. The authors also performed gastric biopsies to collect material for urease tests and histologic studies, with hematoxylin-eosin and fucsin stains in order to identify the microorganism. The gold standard used to detect the presence of H pylori was an analysis of the combined results from the gastric biopsies by urease test and histological method. RESULTS: Antral exfoliative cytology method exhibited 90.3% sensitivity, 66.6% specificity, accuracy of 81.6%, positive predictive value of 82.3% and negative predictive value of 80.0%, in this population with a prevalence of 63.3%. CONCLUSION: Antral exfoliative cytology was demonstrated to be a sensitive, accurate and easy to perform method for investigating H pylori infection in the stomach.