23 research outputs found
Reversal of diabetic-induced myopathy by swimming exercise in pregnant rats:a translational intervention study
Gestational diabetes mellitus (GDM) plus rectus abdominis muscle (RAM) myopathy predicts long-term urinary incontinence (UI). Atrophic and stiff RAM are characteristics of diabetes-induced myopathy (DiM) in pregnant rats. This study aimed to determine whether swimming exercise (SE) has a therapeutic effect in mild hyperglycemic pregnant rats model. We hypothesized that SE training might help to reverse RAM DiM. Mild hyperglycemic pregnant rats model was obtained by a unique subcutaneous injection of 100 mg/kg streptozotocin (diabetic group) or citrate buffer (non-diabetic group) on the first day of life in Wistar female newborns. At 90 days of life, the rats are mated and randomly allocated to remain sedentary or subjected to a SE protocol. The SE protocol started at gestational day 0 and consisted of 60 min/day for 6 days/week in a period of 20 days in a swim tunnel. On day 21, rats were sacrificed, and RAM was collected and studied by picrosirius red, immunohistochemistry, and transmission electron microscopy. The SE protocol increased the fiber area and diameter, and the slow-twitch and fast-twitch fiber area and diameter in the diabetic exercised group, a finding was also seen in control sedentary animals. There was a decreased type I collagen but not type III collagen area and showed a similar type I/type III ratio compared with the control sedentary group. In conclusion, SE during pregnancy reversed the RAM DiM in pregnant rats. These findings may be a potential protocol to consider in patients with RAM damage caused by GDM
Abstract A123: Preclinical evaluation of dual mTOR inhibitor, AZD2014, in prostate cancer
Abstract
Background: An estimated 220,800 cases and 27,540 deaths from prostate cancer (PCa) will occur in the USA during 2015. Altered PI3K/AKT/mTOR signalling contributes to prostate cancer progression and transition to androgen-independent disease, for example one study reported 42% of primary and 100% of metastatic PCa tumours exhibited mutations, altered expression or copy number variations within this pathway. First generation mTOR inhibitors (preferentially inhibit mTORC1), have had limited anti-cancer effect in patients with PCa, possibly due to negative feedback activation of the AKT pathway via mTORC2. The dual mTORC1/2 inhibitor, AZD2014, may overcome this liability. Using a genetically engineered PTEN conditional mouse model (Ptenloxp/loxp;PB-Cre4), we have investigated the effects of AZD2014. The studies complement a clinical trial (NCT02064608) of AZD2014, given to men before radical prostatectomy and are timed for when invasive prostate carcinomas develop in the model around 10-14 months prior to onset of resistance to castration through AKT pathway activation. AZD2014, 15mg/kg daily, oral (with or without castration) or vehicle were administered for 14 days.
Results: AZD2014 was well tolerated with no overt toxicity observed. Pharmacokinetic (PK) analysis revealed mean concentrations of 4.4±2.1μM of AZD2014 in the plasma samples collected 4 hours after day 14 dose. AZD2014 alone or combined with castration inhibited mTORC1 and mTORC2 measured by reductions in p4EBP1(Thr37/46) by approximately 48%±27% (p<0.001) and 37%±11% (p<0.001); pS6(Ser235/236) by 74%±43% (p<0.001) and 44%±13% (p<0.001) and pAKT(Ser473) by 36%±8% (p<0.001) and 20%±3% (p<0.01) as compared to vehicle-treated mice. AZD2014 treatment was anti-proliferative; Ki67 was significantly reduced in AZD2014-treated mice (70%±45%, p<0.001) or AZD2014 plus castration (42%±16%, p<0.001). Apoptosis was detected with cleaved caspase 3 and increased by 3.3-fold (p<0.001) in both AZD2014 or AZD2014 plus castration groups and 2-fold (p<0.001) in the castration only group, respectively. In all cases, 10 mice were used in each group and 80-120 randomly chosen images were analysed using Aperio automatic quantitative algorithms. Tumour volumes (ultrasound imaging) were reduced by 51% (p<0.05) comparing AZD2014 plus castration against control. HRMAS 1H NMR spectroscopy was used on tumour tissue to determine changes in metabolites following treatment and identified that the total choline to creatine ratio (t-Cho/Cr) was reduced by 40% in AZD2014-treated mice tumour samples (p<0.05) as compared to control-treated mice.
Conclusions: Short term (14 days) treatment with AZD2014 with or without castration was associated with both pharmacodynamic and anti-tumour effects. The t-Cho/Cr ratio, previously reported as positively correlated with Gleason score in PCa patients, might be, in addition to our standard mTOR PD markers, utilised as a non-invasive biomarker of AZD2014 activity. The primary and phenotypic biomarker effects of monotherapy with AZD2014 in this relevant genetically engineered mouse model of prostate cancer will be compared with paired biopsies from the ongoing exploratory window study in the prostate cancer patients prior to prostatectomy, and may inform potential novel combination approaches that are translatable to the clinic.
Citation Format: Chiranjeevi Sandi, Antonio Ramos-Montoya, Sergio L. Felisbino, Sarah Jurmeister, Basetti Madhu, Karan Wadhwa, John R. Griffiths, Frances M. Richards, Duncan I. Jodrell, David E. Neal, Sabina Cosulich, Barry Davies, Simon Pacey. Preclinical evaluation of dual mTOR inhibitor, AZD2014, in prostate cancer. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr A123.This is the accepted manuscript. The final version is available at http://mct.aacrjournals.org/content/14/12_Supplement_2/A123.short
Finasteride treatment alters MMP-2 and-9 gene expression and activity in the rat ventral prostate
P>The safety of using finasteride as a prevention of prostate cancer is still under debate. In this study, we investigated the effects of finasteride on the location, gene expression and activities of matrix metalloproteinases -2 and -9, which are involved in the degradation of extracellular matrix components during tissue remodelling and prostate cancer progression, invasion and metastasis. Ventral prostates (VP) from Wistar rats treated with finasteride (25 mg/kg/day) for 7 and 30 days and age-matched controls were evaluated using histology, immunohistochemistry, semi-quantitative RT-PCR and gelatin zymography. Finasteride treatment reduced the epithelial immunostaining of MMP-2 but increased MMP-9 immunostaining in the epithelial cells and in the stroma. The mRNA expression of both MMP-2 and MMP-9 were significantly increased on day 7 of finasteride treatment, mainly for MMP-9 and returned to the control levels by day 30. However, gelatin zymography showed that MMP-9 activity was significantly increased on day 7 of finasteride treatment and remained elevated on day 30 (p < 0.05), while MMP-2 activity was reduced after 30 days of treatment. Finasteride increases MMP-9 and reduces MMP-2 activities in the prostate, which may affect negatively and positively both normal and tumoural prostatic cell behaviour during the treatment. Studies on expression of MMPs in the prostate during different androgen manipulation or cancer chemoprevention strategies can contribute to understand the tissue's overall response and clinical data.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Epithelial-stromal transition of MMP-7 immunolocalization in the rat ventral prostate following bilateral orchiectorny
Epithelial cells from involuting rat ventral prostate (VP) express Matrilysin (MMP-7) mRNA. Herein, we investigated by immunohistochemistry the NIMP-7 protein location and its association with tissue changes following castration in the VP. Normal and castrated adult male Wistar rats were sacrificed at different times after surgery. VP was examined by immunocytochemistry and immunoprecipitation. Castration promoted a shrinking of prostate ducts with an extensive stromal remodeling. In the VP from normal rats, MMP-7 immunoreactivity was found in epithelial secretory granules. Three days after castration, immunostaining for MMP-7 was found in both the epithelial secretory granules and in the stroma just below the epithelium, mainly at the distal ductal tips. At seven and 21 days after castration, the immunostaining for MMP-7 was found only in the stromal space. Immunoprecipitation confirmed the specificity of the primary antibody by rescuing a pro-enzyme form (28 kDa) in the prostate extracts. The present results suggest that MMP-7 participates in the epithelial-stromal interface remodeling of the ventral prostate during the involution achieved by castration, probably in the degradation of components of the epithelial basement membrane. (c) 2007 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved
Identification, content, and distribution of type VI collagen in bovine tendons
Tendon composition changes according to differentiation, mechanical load, and aging. In this study, we attempted to identify, localize, and quantify type VI collagen in bovine tendons. Type VI collagen was identified by the electrophoretic behavior of the alpha chains and Western blotting, and by rotary shadowing. Type VI collagen was extracted from powdered tendon with three sequential 24-h extractions with 4 M guanidine-HCl. The amount of type VI collagen was determined by enzyme-linked immunosorbent assay for purely tensional areas and for the compressive fibrocartilage regions of the deep flexor tendon of the digits, for the corresponding fetal and calf tendons, and for the extensor digital tendon. The distal fibrocartilaginous region of the adult tendon was richer in type VI collagen than the tensional area, reaching as much as 3.3 mg/g (0.33%) of the wet weight. Calf tendons showed an accumulation of type VI at the fibrocartilage site. Immunocytochemistry demonstrated that type VI collagen was evenly distributed in the tensional areas of tendons but was highly concentrated around the fibrochondrocytes in the fibrocartilages. The results demonstrate that tendons are variable with regard to the presence and distribution of type VI collagen. The early accumulation of type VI collagen in the region of calf tendon that will become fibrocartilage in the adult suggests that it is a good marker of fibrocartilage differentiation. Furthermore, the distribution of type VI collagen in tendon fibrocartilage indicates that it organizes the pericellular environment and may represent a survival factor for these cells
Fibrosis-related gene expression in the prostate is modulated by doxazosin treatment
Aims
To gain new insights into the molecular mechanisms of action of doxazosin, we investigated the prostatic stroma ultrastructure and the expression of genes involved with fibrosis, such as collagen type I and III (COL1A1 and COL3A1, respectively) and TGF-beta 1, in the rat ventral prostate.
Main methods
Adult Wistar rats were treated with doxazosin (25 mg/kg/day), and the ventral prostates were excised at 7 and 30 days after treatment. Untreated rats were controls. Ventral prostates were subjected to ultrastructural, immunohistochemical, biochemical and molecular analyses.
Key findings
Doxazosin-treated prostates showed thickened bundles of collagen fibrils, activated fibroblasts, enlarged neurotransmitter vesicles and increased tissue immunostaining for collagen type I and type III when compared to untreated prostates. After 7 and 30 days of doxazosin treatment mRNA expression of COL1A1 and COL3A1 was significantly increased and reduced, respectively, compared to the control group. TGF-beta 1 mRNA and protein levels were increased after 7 days of doxazosin treatment, whereas only mRNA levels remained increased after 30 days of treatment.
Significance
Our data suggest that relaxation of smooth muscle cells by alpha-blockers interferes with the mechanical dynamics of the prostatic stroma extracellular matrix components, generating a pro-fibrotic effect probably via the TGF-beta 1 signaling pathway. Long term treatment with doxazosin may also lead to a reduced turnover of extracellular matrix components. Our results add to a better understanding of the molecular mechanisms behind the effects of alpha-blockade on prostatic histoarchitecture and the response to treatment for benign prostatic hyperplasia9125-2612811287CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informaçãosem informação06/60114-6; 06/60115-2The authors thank the Electron Microscopy Center (Institute of Biosciences, UNESP, Botucatu, SP) for the transmission electron microscopy protocol procedures and for the use of Phillips electron microscope. This work was funded by FAPESP (São Paulo State Research Foundation; grants 06/60114-6, to S.L.F. and 06/60115-2, to F.K.D); by FUNDUNESP (Foundation for Development of Univ Estadual Paulista), by CNPq, and by CAPES do Brazil. This paper represents part of the PhD thesis presented by F.K.D. to the University of Campinas—UNICAMP, Brazi
Combined effect of the finasteride and doxazosin on rat ventral prostate morphology and physiology
P>Finasteride (Fin) and Doxazosin (Dox), alone or in combination, have been widely used in treatment of benign prostatic hyperplasia (BPH) symptoms and recently have been suggested as potential drugs for prostate cancer (PCa)prevention and treatment. However, little is known about the effects of the combination therapy on prostate tissue morphology, physiology and matrix metalloproteinases (MMPs) activity, a special set of enzymes closely related to PCa progression and metastasis. In this study, adult Wistar rats were treated with Fin + Dox (25 mg/kg per day) and the ventral prostate (VP) was excised at days 3 and 30 of treatment to evaluate morphology, cell proliferation, death, transforming growth factor-beta1 (TGF-beta 1) protein expression, MMP-2, MMP-9 activities and MMP-2, MMP-9, TIMP-1 and TIMP-2 mRNA expression. Fin + Dox treatment induced a transient increase in testosterone (T) plasma concentration and a permanent reduction in dihydrotestosterone (DHT). The VP and epithelial cell proliferation were reduced and the stromal collagen fibre volume fraction and apoptosis of the epithelial cell were increased. Fin + Dox treatment also increased the TGF-beta 1 immunoreaction in the epithelium and in the stroma. The mRNAs for MMP-2, TIMPs-1 and -2 expressions after 30 days of treatment were decreased. The mRNA for MMP-9 was not detected in any of the groups analysed. Fin + Dox treatment for 30 days promoted a decrease in gelatinolytic activity of MMP-2 and an increase in MMP-9. In conclusion, combined treatment with Fin and Dox interferes in the epithelial cell behaviour and in the MMPs activity, potentially via TGF-beta 1-mediated and androgen pathways. Our results contribute to a better understanding of the clinical data and also of the molecular mechanisms behind isolated or combined Fin and Dox long-term treatment.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Impact of gestational diabetes and lactational insulin replacement on structure and secretory function of offspring rat ventral prostate
Clinical and experimental studies have shown that exposure to adverse conditions during the critical stages of embryonic, fetal or neonatal development lead to a significantly increased risk of later disease. Diabetes during pregnancy has been linked to increased risk of obesity and diabetes in offspring. Here, we investigated whether mild gestational diabetes mellitus (GDM) followed or not by maternal insulin replacement affects the ventral prostate (VP) structure and function in male offspring at puberty and adulthood. Pregnant rats were divided into the following 3 groups: control (CT); streptozotocin (STZ)-induced diabetes (D); and D plus insulin replacement during lactation (GDI). The male offspring from different groups were euthanized at postnatal day (PND) 60 and 120. Biometrical parameters, hormonal levels and prostates were evaluated. Mild-GDM promoted reduction in the glandular parenchyma and increased collagen deposition. Insulin replacement during lactation restored the VP morphology. Most importantly, mild-GDM decreased the androgen-induced secretory function as determined by prostatein expression, and insulin replacement reversed this effect. Our results demonstrated that mild GDM impairs VP parenchyma maturation, which is associated with an increase in the fibromuscular stroma compartment. Functionally, the reduction in the VP parenchyma decreases the glandular secretory activity as demonstrated by low expression of prostatein, a potent immunosuppressor factor that protects sperm from immunologic damage into the feminine reproductive tract. This change could lead to impairment of reproductive function in male offspring from diabetic mothers. Maternal insulin replacement during the weaning period apparently restores the prostate function in male offspring. (C) 2014 Elsevier Inc. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Protective effect of gamma-tocopherol-enriched diet on N-methyl-N-nitrosourea-induced epithelial dysplasia in rat ventral prostate
Despite recent advances in understanding the biological basis ofprostate cancer (PCa), the management of this disease remains a challenge. Chemoprotective agents have been usedto protect against or eradicateprostatemalignancies. Here, we investigated the protective effect of -tocopherol on N-methyl-N-nitrosourea (MNU)-induced epithelial dysplasia in the rat ventral prostate (VP). Thirty-two male Wistar rats were divided into four groups (n=8): control (CT): healthy control animals fed a standard diet; control+-tocopherol (CT+T): healthy control animals without intervention fed a -tocopherol-enriched diet (20mg/kg); N-methyl-N-nitrosourea (MNU): rats that received a single dose of MNU (30mg/kg) plus testosterone propionate (100mg/kg) and were fed a standard diet; and MNU+-tocopherol (MNU+T): rats that received the same treatment of MNU plus testosterone and were fed with a -tocopherol-enriched diet (20mg/kg). After 4months, the VPs were excised to evaluate morphology, cell proliferation and apoptosis, as well as cyclooxygenase-2 (Cox-2), glutathione-S-transferase-pi (GST-pi) and androgen receptor (AR) protein expression, and matrix metalloproteinase-9 (MMP-9) activity. An increase in the incidence of epithelial dysplasias, such as stratified epithelial hyperplasia and squamous metaplasia, in the MNU group was accompanied by augmented cell proliferation, GST-pi and Cox-2 immunoexpression and pro-MMP-9 activity. Stromal thickening and inflammatory foci were also observed. The administration of a -tocopherol-enriched diet significantly attenuated the adverse effects of MNU in the VP. The incidence of epithelial dysplasia decreased, along with the cell proliferation index, GST-pi and Cox-2 immunoexpression. The gelatinolytic activity of pro-MMP-9 returned to the levels observed for the CT group. These results suggest that -tocopherol acts as a protective agent against MNU-induced prostatic disorders in the rat ventral prostate