Short-term stromal alterations in the rat ventral prostate following alloxan-induced diabetes and the influence of insulin replacement. Micron. 2012;43:326-333. [PMID: 22014851 DOI: 10.1016/j.micron.2011.09.009]

Maternal hyperglycemia affects cell proliferation signalling and stromal organization in the prostate of neonatal and juvenile rat offspring

Gestational diabetes mellitus is a common medical complication during pregnancy. It creates a hyperglycemic environment and impacts offspring development, increasing the risk of long-term complications, including obesity, impaired glucose metabolism and cardiovascular disease. The impact of gestational diabetes on the prostates of adult offspring has already been described; however, it is not known whether these effects are due only to the maternal condition or whether the offspring develop them throughout life. This investigation evaluated the prostates of neonatal and juvenile offspring of hyperglycemic rats due to diabetes. Diabetes was induced with streptozotocin (50 mg/kg, ip) in pregnant Wistar rats and the prostates of 7- or 30-day-old pups from healthy (PC7, PC30) or diabetic (PD7, PD30) mothers were evaluated. We found reduced body weight in pups of PD7 and PD30 and prostate weight in PD30. Prostate branching was not affected, but a reduction in apoptotic levels was associated with impaired acinar bud canalization in neonates. Additionally, PD7 presented reduced ERK1/2 phosphorylation, cell proliferation and collagen, but fibroblasts were increased. In PD30, there was a reduction in the area of the secretory epithelium and stroma, but the luminal area was increased. Moreover, fibroblasts, smooth muscle cells, collagen and metalloproteinase 2 were decreased in these juvenile pups. These data indicate that maternal hyperglycemia inactivates an important cell proliferation signaling pathway in the prostate in the first postnatal days (which is restored in the juvenile period), but it was not sufficient to avoid epithelial and stromal atrophy. This effect on postnatal gland development may impact the reproductive capacity of the prostate in adult life.

Prostatic alterations associated to early weaning and its relation with cocoa powder supplementation. Experimental study in adult wistar rats

Early weaning can predispose the offspring to greater risk of developing chronic diseases in adulthood. It is believed that the consumption of functional foods is able to prevent these effects. The aim of this study is to evaluate the effects of maternal and postnatal cocoa powder supplementation on body mass, metabolism, and morphology of the prostate of early weaned Wistar rats. The animals were divided into four experimental groups according to lactation time (21 or 18 days, n=6, each) as follows: control group (C), cocoa control group (CCa), early weaning group (EW), and cocoa early weaning group (EWCa). The animals were euthanized at 90 days of age. Serum biochemical analysis and prostate histomorphometric evaluation were performed. The animals supplemented with cocoa powder were heavier than their respective controls (p <0.05), although with no difference in food intake among the groups. Likewise, these same groups showed a reduction in the serum glucose in relation to C and EW groups (p <0.0001). With respect to the prostate, there was no difference in smooth muscle and lumen area densities, while the EW group had a lower epithelial height and a higher percentage of mast cells than the C group (p <0.05). On the other hand, the EWCa group managed to reverse these parameters, leveling with the controls. Early weaning resulted in hyperglycemia and important morphological changes in the prostate. In contrast, dietary supplementation with cocoa powder attenuated these effects on the metabolism and prostatic histoarchitecture, proving to be a good nutritional treatment strategy.

Caveola-forming proteins and prostate cancer

Caveolae are specialised and dynamic plasma membrane subdomains, involved in many cellular functions including endocytosis, signal transduction, mechanosensing and lipid storage, trafficking, and metabolism. Two protein families are indispensable for caveola formation and function, namely caveolins and cavins. Mutations of genes encoding these caveolar proteins cause serious pathological conditions such as cardiomyopathies, skeletal muscle diseases, and lipodystrophies. Deregulation of caveola-forming protein expression is associated with many types of cancers including prostate cancer. The distinct function of secretion of the prostatic fluid, and the unique metabolic phenotype of prostate cells relying on lipid metabolism as a main bioenergetic pathway further suggest a significant role of caveolae and caveolar proteins in prostate malignancy. Accumulating in vitro, in vivo, and clinical evidence showed the association of caveolin-1 with prostate cancer grade, stage, metastasis, and drug resistance. In contrast, cavin-1 was found to exhibit tumour suppressive roles. Studies on prostate cancer were the first to show the distinct function of the caveolar proteins depending on their localisation within the caveolar compartment or as cytoplasmic or secreted proteins. In this review, we summarise the roles of caveola-forming proteins in prostate cancer and the potential of exploiting them as therapeutic targets or biological markers.

Fetal programming by high-fat diet promoted the decreased of the prostate in adult Wistar albino rats

We investigated the effect of a high-fat diet on body metabolism and ventral prostate morphology in 4-months-old offspring. The mother was fed with a control (C) or a high-fat (HF) diet during gestation and lactation. At weaning, the offspring diet remained the same (C/C, n = 8; HF/HF, n = 8) or it was switched (C/HF, n = 8; HF/C, n = 9). Biometry, blood pressure (BP), glucose, lipid metabolism and ventral prostate were evaluated. Triacylglycerol of HF/C increased, and the C/HF group had decreased HDL-c levels (P = 0.0005 and P = 0.0100, respectively). All groups on the HF diet presented hyperglycemia (P = 0.0064). Serum testosterone diminished in the C/HF group (P = 0.0218). The HF diet, regardless of the period, reduced prostatic acinar area (P < 0.0001). The epithelium height was smaller in HF/C and HF/HF groups compared with C/C and C/HF (P < 0.0001), and the volume density of epithelium was lower in HF/C group compared with the C/C and C/HF (P = 0.0024). The volume density of smooth muscle cells diminished in C/HF and HF/C (P = 0.0013), and the volume density of connective tissue was reduced in HF/C and HF/HF (P < 0.0001). High-fat diet intake during prenatal and postnatal life leads to prostatic atrophy, which may impair prostate secretory activity and contractility, and thus disturb reproductive function in adulthood.

Effect of diabetes on collagen metabolism and hypoxia in human gingival tissue: a stereological, histopathological, and immunohistochemical study

Diabetes mellitus and periodontitis are chronic inflammatory diseases that disrupt soft tissue metabolism. The diseases separately or together increase apoptosis in gingival fibroblast cells and reduce cell renewal. We investigated the effects of diabetes and periodontitis on the composition and structure of gingival connective tissue. We used gingival biopsies from 16 healthy individuals (control group, C), 16 type 2 diabetic patients with chronic periodontitis (diabetes + periodontitis group, D + P) and 16 healthy chronic periodontitis patients (periodontitis group, P). Biopsies were obtained under local anesthesia. Clinical attachment level (CAL), gingival index (GI) and plaque index (PI) were measured prior to gingival biopsies. Fibroblast cells were counted stereologically. Inflammatory cells were counted histomorphometrically. Hypoxia-inducible factor (HIF)-1α, lysyl hydroxylase (PLOD-2), neutrophil collagenase (MMP-8), and vascular endothelial growth factor (VEGF) levels were evaluated immunohistochemically. CAL, GI and PI for the C group were lower than for the other groups (p < 0.05). Fibroblast cell counts were lower for the D + P group than for the other groups (p < 0.05). Diabetes increased inflammatory cell numbers in the D and D + P groups compared to the C and P groups. MMP-8 levels were higher for the D + P group than for the other groups. VEGF was elevated in both the P and D + P groups compared to the C group, while HIF-1α and PLOD-2 levels were comparable. Diabetes increased tissue destruction and inflammation, and decreased fibroblast cell numbers without affecting collagen crosslinking and HIF-1α levels.

Path of translational discovery of urological complications of obesity and diabetes

Diabetes mellitus (DM) is a prevalent chronic disease. Type 1 DM (T1DM) is a metabolic disorder that is characterized by hyperglycemia in the context of absolute lack of insulin, whereas type 2 DM (T2DM) is due to insulin resistance-related relative insulin deficiency. In comparison with T1DM, T2DM is more complex. The natural history of T2DM in most patients typically involves a course of obesity to impaired glucose tolerance, to insulin resistance, to hyperinsulinemia, to hyperglycemia, and finally to insulin deficiency. Obesity is a risk factor of T2DM. Diabetes causes some serious microvascular and macrovascular complications, such as retinopathy, nephropathy, neuropathy, angiopathy and stroke. Urological complications of obesity and diabetes (UCOD) affect quality of life, but are not well investigated. The urological complications in T1DM and T2DM are different. In addition, obesity itself affects the lower urinary tract. The aim of this perspective is to review the available data, combined with the experience of our research teams, who have spent a good part of last decade on studies of association between DM and lower urinary tract symptoms (LUTS) with the aim of bringing more focus to the future scientific exploration of UCOD. We focus on the most commonly seen urological complications, urinary incontinence, bladder dysfunction, and LUTS, in obesity and diabetes. Knowledge of these associations will lead to a better understanding of the pathophysiology underlying UCOD and hopefully assist urologists in the clinical management of obese or diabetic patients with LUTS.

Streptozotocin-Induced Maternal Hyperglycemia Increases the Expression of Antioxidant Enzymes and Mast Cell Number in Offspring Rat Ventral Prostate

Gestational diabetes mellitus (GDM) has increased in recent years. Although the cellular and molecular mechanisms involved in GDM-increased risk factors to offspring remained poorly understood, some studies suggested an association between an increase in oxidative stress induced by maternal hyperglycemia and complications for both mothers and newborns. Here, we investigated the impact of maternal hyperglycemia followed by maternal insulin replacement during lactation on the expression of antioxidant enzymes and mast cell number in offspring ventral prostate (VP) at puberty. Pregnant rats were divided into three groups: control (CT); streptozotocin-induced maternal hyperglycemia (MH); and MH plus maternal insulin replacement during lactation (MHI). Male offspring were euthanized at postnatal day (PND) 60 and the VP was removed and processed for histology and Western blotting analyses. Maternal hyperglycemia delayed prostate maturation, and increased mast cell number catalase (CAT), superoxide dismutase (SOD), glutatione-s-transferase (GST-pi), and cyclooxygenase-2 (Cox-2) expression in the offspring of hyperglycemic dams. Maternal insulin replacement restored VP structure, mast cell number and antioxidant protein expression, except for Cox-2, which remained higher in the MHI group. Thus, an increase in oxidative stress induced by intrauterine hyperglycemia impacts prostate development and maturation, which persists until puberty. The overall improvement of maternal metabolism after insulin administration contributes to the restoration of prostate antioxidant enzymes and secretory function. Taken together, our results highlighted that imbalanced physiological maternal-fetal interaction contributes to the impairment of reproductive performance of the offspring from diabetic mothers. Anat Rec, 300:291-299, 2017. © 2016 Wiley Periodicals, Inc.

Influence of Melatonin on the Proliferative and Apoptotic Responses of the Prostate under Normal and Hyperglycemic Conditions

The antitumor properties of melatonin (MLT) are known for prostate cancer cells. This study investigated whether MLT affects prostate maturation and interferes with tissue injuries induced by diabetes. MLT was administered to Wistar rats from 5 weeks of age in the drinking water (10 μg/kg b.w.), and diabetes was induced at the 13th week by streptozotocin (4.5 mg/100g b.w., i.p.). The animals were euthanized in the 14th and 21st weeks. MLT reduced the immunostained cells for androgen receptor (AR) by 10% in younger rats. Diabetes decreased cell proliferation and increased apoptosis. MLT treatment impeded apoptosis (p = 0.02) and augmented proliferation (p = 0.0008) and PCNA content in prostate following long-term diabetes due to restoration of testosterone levels and expression of melatonin receptor type 1B. The effect of MLT (500 µM, 5 mM, and 10 mM) on androgen-dependent (22Rv1) and androgen-independent (PC3) cancer cells and human prostate epithelial cells (PNTA1) under normal and hyperglycemic conditions (HG, 450 mg/dL) was analyzed. Contrary to PNTA1 and 22Rv1 cells, MLT improved the proliferation of PC3 cells in hyperglycemic medium. The combined data indicated that MLT had proliferative and antiapoptotic effects in prostate cells subjected to HG levels and it seems to involve specific MLT pathways rather than AR.

Effect of Melatonin Intake on Oxidative Stress Biomarkers in Male Reproductive Organs of Rats under Experimental Diabetes

This study investigated the antioxidant system response of male reproductive organs during early and late phases of diabetes and the influence of melatonin treatment. Melatonin was administered to five-week-old Wistar rats throughout the experiment, in drinking water (10 μg/kg b.w). Diabetes was induced at 13 weeks of age by streptozotocin (4.5 mg/100 g b.w., i.p.) and animals were euthanized with 14 or 21 weeks old. Activities of catalase (CAT), glutathione-S-transferase (GST), glutathione peroxidase (GPx), and lipid peroxidation were evaluated in prostate, testis, and epididymis. The enzymes activities and lipid peroxidation were not affected in testis and epididymis after one or eight weeks of diabetes. Prostate exhibited a 3-fold increase in GPx activity at short-term diabetes and at long-term diabetes there were 2- and 3-fold increase in CAT and GST, respectively (p ≤ 0.01). Melatonin treatment to healthy rats caused a 47% increase in epididymal GPx activity in 14-week-old rats. In prostate, melatonin administration normalized GST activity at both ages and mitigated GPx at short-term and CAT at long-term diabetes. The testis and epididymis were less affected by diabetes than prostate. Furthermore, melatonin normalized the enzymatic disorders in prostate demonstrating its effective antioxidant role, even at low dosages.

Comparative secretome analysis of rat stomach under different nutritional status

Obesity is a major public health threat for many industrialised countries. Bariatric surgery is the most effective treatment against obesity, suggesting that gut derived signals are crucial for energy balance regulation. Several descriptive studies have proven the presence of gastric endogenous systems that modulate energy homeostasis; however, these systems and the interactions between them are still not well known. In the present study, we show for the first time the comparative 2-DE gastric secretome analysis under different nutritional status. We have identified 38 differently secreted proteins by comparing stomach secretomes from tissue explant cultures of rats under feeding, fasting and re-feeding conditions. Among the proteins identified, glyceraldehyde-3-phosphate dehydrogenase was found to be more abundant in gastric secretome and plasma after re-feeding, and downregulated in obesity. Additionally, two calponin-1 species were decreased in feeding state, and other were modulated by nutritional and metabolic conditions. These and other secreted proteins identified in this work may be considered as potential gastrokines implicated in food intake regulation.

BIOLOGICAL SIGNIFICANCE

The present work has an important impact in the field of obesity, especially in the regulation of body weight maintenance by the stomach. Nowadays, the most effective treatment in the fight against obesity is bariatric surgery, which suggests that stomach derived signals might be crucial for the regulation of the energy homeostasis. However, until now, the knowledge about the gastrokines and its mechanism of action has been poorly elucidated. In the present work, we had updated a previously validated explant secretion model for proteomic studies; this analysis allowed us, for the first time, to study the gastric secretome without interferences from other organs. We had identified 38 differently secreted proteins comparing ex vivo cultured stomachs from rats under feeding, fasting and re-feeding regimes. The results in the present article provide novel targets to study the role of the stomach in body weight and appetite regulation, and suggest new potential therapeutic targets for treating obesity.

Key participants of the tumor microenvironment of the prostate: an approach of the structural dynamic of cellular elements and extracellular matrix components during epithelial-stromal transition

Cancer is a multistep process that begins with the transformation of normal epithelial cells and continues with tumor growth, stromal invasion and metastasis. The remodeling of the peritumoral environment is decisive for the onset of tumor invasiveness. This event is dependent on epithelial-stromal interactions, degradation of extracellular matrix components and reorganization of fibrillar components. Our research group has studied in a new proposed rodent model the participation of cellular and molecular components in the prostate microenvironment that contributes to cancer progression. Our group adopted the gerbil Meriones unguiculatus as an alternative experimental model for prostate cancer study. This model has presented significant responses to hormonal treatments and to development of spontaneous and induced neoplasias. The data obtained indicate reorganization of type I collagen fibers and reticular fibers, synthesis of new components such as tenascin and proteoglycans, degradation of basement membrane components and elastic fibers and increased expression of metalloproteinases. Fibroblasts that border the region, apparently participate in the stromal reaction. The roles of each of these events, as well as some signaling molecules, participants of neoplastic progression and factors that promote genetic reprogramming during epithelial-stromal transition are also discussed.

Value of insulin, C-peptide and blood glucose detection in early diagnosis of diabetes with liver injury

AIM: To assess the value of insulin, C-peptide and blood glucose detection in the early diagnosis of diabetes with liver damage.

METHODS: Sixty-one diabetic patients with liver injury treated at our hospital were enrolled as a study group, 55 diabetic patients with normal liver function as a control group, and 50 healthy people as a normal group. The levels of blood glucose, insulin and C-peptide among the three groups were compared.

RESULTS: Fasting blood glucose and 2-h postprandial blood glucose levels were significantly higher in the study group and control group than in the normal group (t = 2.317, 2.918, P < 0.05), and in the study group than in the control group (t = 3.084, 4.431, P < 0.05). Fasting insulin, 2-h postprandial fasting insulin, fasting C-peptide, 2-h postprandial C-peptide and insulin resistance index were significantly higher in the study group and control group than in the normal group (t = 2.276, 3.426, 5.317, 3.342, P < 0.05), and in the study group than in the control group (t = 6.436, 3.341, 2.195, 3.341, 3.426, 5.317, 3.342, P < 0.05). In diabetes patients with liver injury, blood glucose levels were positively correlated with insulin and C-peptide (r = 0.589, 0.724, P < 0.05). The diagnostic sensitivity and specificity of combined detection of the three indexes were 87.1% and 94.8%, significantly higher than those of detection of any single index.

CONCLUSION: Combined detection of blood glucose, insulin and C-peptide is helpful for early diagnosis of diabetes with liver injury.

Effects of maternal diabetes on male offspring: high cell proliferation and increased activity of MMP-2 in the ventral prostate

This study presents a comprehensive view of the histological and functional status of the prostate of adult rat offspring of mothers subjected to gestational diabetes induced by alloxan. The ventral prostate of male adult offspring of diabetic (DP) or normal (CP) mothers was evaluated for collagen fibres, cell death, fibroblasts, smooth muscle cells, cell proliferation, matrix metalloproteinases (MMPs), androgen receptors (AR), transforming growth factor β1 (TGFβ-1), catalase and total antioxidant activity. The prostates of DP animals were lower in weight than those of the CP group. The DP group also exhibited hyperglycaemia and hypotestosteronemia, higher cell proliferation and AR expression, a reduction in α-actin (possibly interfering with the reproductive function of the prostate), and enhanced activity of MMP-2, although the absolute content of MMP-2 was lower in this group. These findings were associated with increased TGFβ-1 and decreased collagen distribution. The prostates of DP rats additionally exhibited reductions in catalase and total antioxidant activity. Thus, rats developing in a diabetic intrauterine environment have glycaemic and hormonal changes that impact on the structure and physiology of the prostate in adulthood. The increased AR expression possibly leads to elevated cell proliferation. Stromal remodelling was characterized by enhanced activity of MMP-2 and collagen degradation, even with increased TGFβ-1 activation. These changes associated with increased oxidative stress might interfere with tissue architecture and glandular homeostasis.

Caveola-forming proteins caveolin-1 and PTRF in prostate cancer

The expression of caveola-forming proteins is dysregulated in prostate cancer. Caveolae are flask-shaped invaginations of the plasma membrane that have roles in membrane trafficking and cell signalling. Members of two families of proteins--caveolins and cavins--are known to be required for the formation and functions of caveolae. Caveolin-1, the major structural protein of caveolae, is overexpresssed in prostate cancer and has been demonstrated to be involved in prostate cancer angiogenesis, growth and metastasis. Polymerase I and transcript release factor (PTRF) is the only cavin family member necessary for caveola formation. When exogenously expressed in prostate cancer cells, PTRF reduces aggressive potential, probably via both caveola-mediated and caveola-independent mechanisms. In addition, stromal PTRF expression decreases with progression of the disease. Evaluation of caveolin-1 antibodies in the clinical setting is underway and it is hoped that future studies will reveal the mechanisms of PTRF action, allowing its targeting for therapeutic purposes.