Combined effect of the finasteride and doxazosin on rat ventral prostate morphology and physiology

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ultrastructural Alterations in the Midgut of Diplopods after Subchronic Exposure to Substrate Containing Sewage Mud

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Regeneration of the Corneal Epithelium after Debridement of its Central Region: An Autoradiographic Study on Rabbits

Purpose: To investigate the proliferative behavior of the corneal and limbal epithelia after debridement on the central region of the rabbit cornea. Methods: After scraping a circular epithelial area, 5 mm in diameter, in the center of the cornea, (3)H-thymidine ((3)H-TdR) was injected intravitreally, and the rabbits killed from 1 to 49 days afterward. The cornea, together with the adjacent conjunctiva, was processed for autoradiography. Results: The regenerating epithelium at the center of the cornea exhibited high frequencies of labeled nuclei when compared to controls. The mitotic indexes for the limbus were comparable in experimental and control eyes. The unique basal stratum of the limbal epithelium exhibited quick proliferation and vertical migration in all eyes. Cells that remained labeled for four weeks or more were observed throughout the corneal epithelium, including its basal stratum, and this did not depend on epithelial damage. Conclusion: Corneal epithelium wounds are healed by sliding and proliferation of cells surrounding the epithelial gap without any evidence for the participation of the limbal epithelium. Daughter cells labeled with (3)H-TdR were visualized in all layers of the corneal epithelium up to 7 weeks after the DNA precursor injection. However, at this long interval, the only labeled cells in the limbus were in the suprabasal layers.

Testosterone stimulates growth and secretory activity of the female prostate in the adult gerbil (Meriones unguiculatus)

The prostate of the female gerbil (Meriones unguiculatus) is similar to the human female prostate (Skene gland) and, despite its reduced size, it is functional and shows secretory activity. However, virtually nothing is known about its physiological regulation. This study was thus undertaken to evaluate the behavior of the gerbil female prostate in a hyperandrogenic condition. Adult females received subcutaneous injections of testosterone cypionate (1 mg/kg body weight every 48 h) up to 21 days. Circulating levels of testosterone and estradiol were monitored, and the prostate and ovaries subjected to structural and immunocytochemical analyses. The treatment resulted in sustained high levels of circulating testosterone, and caused a transient increase in estradiol. There was an increase in epithelial cell proliferation accompanied by significant reorganization of the epithelium and an apparent reduction in secretory activity, followed by a progressive increase in luminal volume density and accumulation of secretory products. Immunocytochemistry identified the expression of androgen receptor and a prostate-specific antigen (PSA)-related antigen in prostatic epithelial cells. A circulating PSA-related antigen was also found, and its concentration showed strong negative correlation with circulating estrogen. Epithelial dysplasia was detected in the prostate of treated females. Analysis of the ovaries showed the occurrence of a polycystic condition and stromal cell hyperplasia. The results indicate that testosterone has a stimulatory effect on the female prostate, inducing epithelial cell proliferation, differentiation, secretory activity, and dysplasia. The results also suggest that prostatic growth and activity, polycystic ovaries, and ovarian stromal cell hyperplasia are related to a hyperandrogenic condition in females.

Glyceraldehyde-3-phosphate dehydrogenase of Paracoccidioides brasiliensis is a cell surface protein involved in fungal adhesion to extracellular matrix proteins and interaction with cells

The pathogenic fungus Paracoccidioides brasiliensis causes paracoccidioidomycosis, a pulmonary mycosis acquired by inhalation of fungal airborne propagules, which may disseminate to several organs and tissues, leading to a severe form of the disease. Adhesion to and invasion of host cells are essential steps involved in the infection and dissemination of pathogens. Furthermore, pathogens use their surface molecules to bind to host extracellular matrix components to establish infection. Here, we report the characterization of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of P. brasiliensis as an adhesin, which can be related to fungus adhesion and invasion. The P. brasiliensis GAPDH was overexpressed in Escherichia coli, and polyclonal antibody against this protein was obtained. By immunoelectron microscopy and Western blot analysis, GAPDH was detected in the cytoplasm and the cell wall of the yeast phase of P. brasiliensis. The recombinant GAPDH was found to bind to fibronectin, laminin, and type I collagen in ligand far-Western blot assays. of special note, the treatment of P. brasiliensis yeast cells with anti-GAPDH polyclonal antibody and the incubation of pneumocytes with the recombinant protein promoted inhibition of adherence and internalization of P. brasiliensis to those in vitro-cultured cells. These observations indicate that the cell wall-associated form of the GAPDH in P. brasiliensis could be involved in mediating binding of fungal cells to fibronectin, type I collagen, and laminin, thus contributing to the adhesion of the microorganism to host tissues and to the dissemination of infection.

Partitioning of the glucoamylase activity at the cell surfaces in cultures of Saccharomyces

Glucoamylases have been used with alpha-amylases for the industrial conversion of starch into glucose. However, little is known about the properties of this glycosylated protein retained in the cell wall of Saccharomyces as well as its role in the saccharification and fermentation of amylaceous substrates, notably in high cell density processes. In most of the strains assayed, decreases in biomass formation were followed by increases in glucoamylase secretion (expressed as U/mg(biomass) in 1 ml of culture) when glucose was exchanged for starch as carbon source or the growth temperature was raised from 30 to 35 degrees C. Despite the losses in viability, significant increases in the activity of the wall fraction occurred when cultures of thermotolerant yeasts propagated at 30 degrees C or washed cells resuspended in buffer solution were heated to 60 degrees C for 60-80 min prior to amylolytic assays. Thus, intact cells of thermotolerant yeasts can be used as colloidal biocatalysts in starch degradation processes. (C) 2005 Published by Elsevier Ltd.

A morphometric ultrastructural study of the seminal vesicle of rats submitted to experimental chronic alcoholism

The effects of chronic alcohol ingestion on the secretory epithelium of the seminal vesicle were studied in rats (Rattus norvegicus). Male adult albino Wistar rats were divided into two groups: alcoholic and control. Tips of the seminal vesicle were removed and prepared for light and electron microscopy. Ultrastructural observations on the epithelial cells of the seminal vesicle showed reduced epithelial cell size, decreased apical secretory vacuoles, irregularly shaped nuclei with deep infoldings, increased lipid droplets and dense bodies, a small number of microvilli covering the cell surface, and signs of degeneration. In addition to the hormonal effects, alcohol may act on the secretory epithelium of the seminal vesicle.

REDUCTION OF CELL PROLIFERATIVE ACTIVITIES OF GASTRIC STUMP ADENOMATOUS HYPERPLASIAS AFTER BILE REFLUX DIVERSION IN RATS

Previously we reported the majority of lesions induced hy bile reflux, in the absence of chemical carcinogens, in the rat remnant stomach to consist primarily of gastric type and secondarily of intestinal type cells, and that they are reversible after diversion of bile reflux. The present study was designed to evaluate changes in proliferative activities in cells of each type under these conditions. The frequency of adenomatous hyperplasia (AH) induced in the gastric stump mucosa by duodenal content reflux after Billroth II partial gastrectomy (BII) increased until the 54th week of the experiment. Roux-en-Y (RY) surgical procedure which prevents duodenal reflux performed at the 24th or 36th week after BII led to a decrease in AH. Cell content of the lesions was analyzed using routine H&E staining, immunohistochemical staining for pepsinogen isoenzyme 1 and histochemical procedures for mucins (paradoxical concanavalin A, galactose oxidase Schiff and sialidase galactose oxidase Schiff reactions) and proliferation in each compartment evaluated by an immunohistochemical method using bromodeoxyuridine (BrdU) and a monoclonal antibody against BrdU. At the 54th week the number of BrdU-labeled cells per normal pyloric column was significantly (P < 0.05) increased to 10.63/pit after the BII operation, while it diminished to 5.23/pit after RY diversion, this being the same level as with the RY procedure alone. AH maintained a high rate of BrdU incorporation at 12.7% after BII operation, which was also significantly reduced (P < 0.01) to 7.0% by the RY surgery. The intestinal type cell showed highest (22.2%), the surface mucous type cell showed the next (16.5%) and the pyloric gland type cell showed lowest (5.2%) BrdU labeling indices after BII operation. All the cell types in AH showed similar proportional decreases in BrdU incorporation after RY diversion. Thus surgical intervention reverses the cell proliferation caused by bile reflux in the gastric stump.

Ultrastructural alterations in colon absorptive cells of alloxan-induced diabetic rats submitted to long-term physical training

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Immunohistochemical Characterization of Canine Prostatic Intraepithelial Neoplasia

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Doxazosin reduces cell proliferation and increases collagen fibers in rat prostatic lobes

We investigated the effects of doxazosin (Dox), an alpha-adrenoceptor antagonist used clinically for the treatment of benign prostatic hyperplasia (BPH), on the rat prostatic complex by assessing structural parameters, collagen fiber content, cell proliferation, and apoptosis. Adult Wistar rats were treated with Dox (25 mg/kg per day), and the ventral (VP), dorsolateral, and anterior prostate (AP) regions of the prostate complex were excised at 3, 7, and 30 days after treatment. At 24 h before being killed, the rats were injected once with 5-bromodeoxyuridine (BrdU; thymidine analog) to label mitotically active cells. The prostates were weighed and processed for histochemistry, morphometry-stereology, immunohistochemistry for BrdU, Western blotting for proliferating cell nuclear antigen (PCNA), and the TUNEL reaction for apoptosis. Dox-treated prostate lobes at day 3 presented increased weight, an enlarged ductal lumen, low cubical epithelial cells, reduced epithelial folds, and stretched smooth muscle cells. However, at day 30, the prostates exhibited a weight reduction of ∼20% and an increased area of collagen and reticular fibers in the stromal space. Dox also reduced epithelial cell proliferation and increased apoptosis in the three prostatic lobes. Western blotting for PCNA confirmed the reduction of cell proliferation by Dox, with the AP and VP being more affected than the dorsal prostate. Thus, Dox treatment alters epithelial cell behavior and prostatic tissue mechanical demand, inducing tissue remodeling in which collagen fibers assume a major role. © 2007 Springer-Verlag.

Effects of the ethyl acetate fraction of Alchornea triplinervia on healing gastric ulcer in rats

Alchornea triplinervia (Spreng.) Muell. Arg (Euphorbiaceae) is a medicinal plant commonly used by people living in the Cerrado region of Brazil to treat gastrointestinal ulcers. We previously described the gastroprotective action of methanolic extract (ME) of Alchornea triplinervia and the ethyl acetate fraction (EAF) in increasing of prostaglandin E 2 (PGE 2) gastric levels in the mucosa. In this work we evaluated the effect of EAF in promoting the healing process in rats with acetic acid-induced gastric ulcers. In addition, toxicity was investigated during treatment with EAF. After 14 days of treatment with EAF, the potent stimulator of gastric cell proliferation contributed to the acceleration of gastric ulcer healing. Upon immunohistochemical analysis, we observed a pronounced expression of COX-2, mainly in the submucosal layer. The 14-day EAF treatment also significantly increased the number of neutrophils in the gastric mucosa regeneration area. The EAF induced angiogenesis on gastric mucosa, observed as an increase of the number of blood vessels supplying the stomach in rats treated with EAF. Oral administration for 14 days of the ethyl acetate fraction from Alchornea triplinervia accelerated the healing of gastric ulcers in rats by promoting epithelial cell proliferation, increasing the number of neutrophils and stimulation of mucus production. This fraction, which contained mainly phenolic compounds, contributed to gastric mucosa healing. © 2011 by the authors; licensee MDPI, Basel, Switzerland.

Implications of intrauterine protein malnutrition on prostate growth, maturation and aging

Aims Maternal malnutrition by low protein diet is associated with an increased incidence of metabolic disorders and decreased male fertility in adult life. This study aimed to assess the impact of maternal protein malnutrition (MPM) on prostate growth, tissue organization and lesion incidence with aging. Main methods Wistar rat dams were distributed into two groups, which were control (NP; fed a normal diet containing 17% protein) or a restricted protein diet (RP, fed a diet containing 6% protein) during gestation. After delivery all mothers and offspring received a normal diet. Biometrical parameters, hormonal levels and prostates were harvested at post-natal days (PND) 30, 120 and 360. Key findings MPM promoted low birth weight, decreased ano-genital distance (AGD) and reduced androgen plasma levels of male pups. Prostatic lobes from RP groups presented reduced glandular weight, epithelial cell height and alveolar diameter. The epithelial cell proliferation and collagen deposition were increased in RP group. Incidences of epithelial dysplasia and prostatitis were higher in the RP offspring than in the NP offspring at PND360. Significance Our findings show that MPM delays prostate development, growth and maturation until adulthood, probably as a result of low testosterone stimuli. The higher incidence of cellular dysplasia and prostatitis suggests that MPM increases prostate susceptibility to diseases with aging. © 2013 Elsevier Inc.

Effects of exposure to estradiol and estradiol plus testosterone on the mongolian gerbil (Meriones unguiculatus) female prostate

The female prostate is a differentiated organ found in several mammal species, including humans and rodents. This gland has been related to important functions on female reproductive biology. Although the factors, which regulate prostate's development and activity are not well known, its functionality has been related to steroid hormones. It is well established that cyclic changes of estradiol and progesterone levels promote histophysiological adaptations of the whole female body. In contrast, only a few is found about those adaptations in female prostate. Thus, this study aimed to evaluate the effect of estradiol and estradiol+testosterone association on gerbil female prostate in order to verify, which hormonal associations are necessary to its homeostasis. For this, adult females had the ovaries surgically removed. After recovering, they received estradiol and estradiol+testosterone doses through 30 days, each 48 h. The prostatic tissue underwent morphological and morphometric-estereological analysis. Hormonal restriction caused great gland involution and decreased secretory activity, aspects that were reverted by exposure to estradiol and estradiol+testosterone. However, these hormones were not able to re-establish the normal prostate histoarchitecture. The immunoreaction of steroid receptors (ER-α, ER-β, and AR) responded differently among the experimental and control groups, and PCNA assay showed a decrease in epithelial cell proliferation within groups that had hormone privation. Therefore, we conclude that estradiol and testosterone are able to influence prostate morphophysiology and the maintenance of gland homeostasis depends on a balance among these and other hormones. © 2013 Wiley Periodicals, Inc.

Mechanism and effect of esculetin in an experimental animal model of inflammatory bowel disease

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)