Osvaldo Mazza
University of Buenos Aires
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Featured researches published by Osvaldo Mazza.
British Journal of Cancer | 2007
P Sacca; Roberto Meiss; G Casas; Osvaldo Mazza; J C Calvo; N Navone; Elba Vazquez
The role of oxidative stress in prostate cancer has been increasingly recognised. Acute and chronic inflammations generate reactive oxygen species that result in damage to cellular structures. Haeme oxygenase-1 (HO-1) has cytoprotective effects against oxidative damage. We hypothesise that modulation of HO-1 expression may be involved in the process of prostate carcinogenesis and prostate cancer progression. We thus studied HO-1 expression and localisation in 85 samples of organ-confined primary prostate cancer obtained via radical prostatectomy (Gleason grades 4–9) and in 39 specimens of benign prostatic hyperplasia (BPH). We assessed HO-1 expression by immunohistochemical staining. No significant difference was observed in the cytoplasmic positive reactivity among tumours (84%), non-neoplastic surrounding parenchyma (89%), or BPH samples (87%) (P=0.53). Haeme oxygenase-1 immunostaining was detected in the nuclei of prostate cancer cells in 55 of 85 (65%) patients but less often in non-neoplastic surrounding parenchyma (30 of 85, 35%) or in BPH (9 of 39, 23%) (P<0.0001). Immunocytochemical and western blot analysis showed HO-1 only in the cytoplasmic compartment of PC3 and LNCaP prostate cancer cell lines. Treatment with hemin, a well-known specific inducer of HO-1, led to clear nuclear localisation of HO-1 in both cell lines and highly induced HO-1 expression in both cellular compartments. These findings have demonstrated, for the first time, that HO-1 expression and nuclear localisation can define a new subgroup of prostate cancer primary tumours and that the modulation of HO-1 expression and its nuclear translocation could represent new avenues for therapy.
American Journal of Hypertension | 2000
Jorge E. Toblli; Inés Stella; Felipe Inserra; León Ferder; Federico Zeller; Osvaldo Mazza
Erectile dysfunction has an increased prevalence in hypertensive patients and is associated with cardiovascular diseases. For many years the discussion has been polarized on whether in hypertensive patients, it is the arterial hypertension or the antihypertensive therapy that is the cause of male erectile dysfunction. The aim of our study was to determine the morphologic changes in cavernous tissue (CT) in an animal model of arterial hypertension. Male spontaneously hypertensive rats (SHR) (n = 15) and normotensive Wistar-Kyoto (WKY) rats (n = 15) were studied for 8 months. Animals were allowed to drink tap water and fed a standard rat chow ad libitum. Systolic blood pressure (SBP) was measured monthly by the tail/cuff method. At the end of the experiment all the animals were sacrificed for microscopic studies. Cavernous tissue was processed by hematoxylin and eosin, Massons trichrome, and monoclonal anti-alpha smooth muscle actin. Cavernous smooth muscle (CSM) and vascular smooth muscle (VSM) proliferation and CT fibrosis were evaluated by a semiquantitative score. SHR showed a higher proliferative score in CSM (2.7 +/- 0.28 v 1.1 +/- 0.07; P < .001), as well as in VSM (2.7 +/- 0.25 v 1 +/- 0.05; P < .001), and higher CT fibrosis score (2.8 +/- 0.28 v 0.1 +/- 0.07; P < .001), when compared to WKY rats. Furthermore, SHR showed a positive correlation between SBP and CSM proliferative score (r2 = 0.9277), SBP and VSM proliferative score (r2 = 0.8828), and SBP and CT fibrosis score (r2 = 0.7775). In addition, an increase in the surrounding connective tissue at the perineurium and endoneurium of the amielinic nerves in CT was observed in the SHR group. According to these results we conclude that SHR present morphologic changes in vessels as well as in cavernous spaces of the erectile tissue that have a high positive correlation with high blood pressure. Moreover, the increase in extracellular matrix expansion seems to affect not only the interstitium but also the neural structures of the penis.
American Journal of Nephrology | 2004
Jorge E. Toblli; Inés Stella; Osvaldo Mazza; León Ferder; Felipe Inserra
Background: Erectile dysfunction is highly prevalent in hypertensive patients. Since both angiotensin II receptor type-1 blockers (ARBs) and calcium antagonists are current and effective antihypertensive drugs, the aim of this study was to determine possible differences between ARBs and calcium antagonists concerning the protection of penile structures from the deleterious effects of arterial hypertension. Methods and Results: During 6 months, 3 groups of male spontaneously hypertensive rats (SHR) and 1 of Wistar-Kyoto (WKY) rats, as a control group, were studied: SHR without treatment; SHR with losartan (L) 30 mg/kg/day; SHR with amlodipine (A) 3 mg/kg/day, and WKY without treatment. Cavernous smooth muscle (CSM) and vascular smooth muscle (VSM) from cavernous arteries, cavernous tissue fibrosis and collagen type III (COL III) were evaluated. After 6 months, SHR+L and SHR+A showed a similar reduction in blood pressure compared with untreated SHR. However, only SHR+L and control WKY presented significantly lower values of: CSM (p < 0.01), VSM (p < 0.01), and COL III ( p < 0.01) when compared with either untreated SHR or SHR+A. There was also a positive correlation between left ventricular mass and proteinuria with VSM from cavernous arteries, CSM and COL III in untreated SHR and SHR+A. These relations were not present in SHR+L and WKY. Conclusion: Although losartan and amlodipine achieved similar blood pressure control, losartan but not amlodipine showed a significant protective role against structural changes in the vessels and cavernous spaces of the erectile tissue caused by arterial hypertension.
The Journal of Urology | 2001
Osvaldo Mazza; Germán Chéliz
PURPOSE Reconstructing a penile stump secondary to trauma or cancer should result in satisfactory penile function and appearance. The lack of penile skin, stump retraction in the scrotum and stenosis of the neomeatus must be resolved in these cases. MATERIALS AND METHODS A 2-stage surgical technique with a scrotal flap was used in 34 patients with a mean age of 43.2 years to reconstruct the glans. Mean followup was 73.2 months. After penectomy a scrotal flap was designed and its distal extreme was transferred to the penile stump. The urethral end was sutured to a hole in the scrotal flap and the flap borders were sutured to the adjacent albuginea. The flap pedicle was resected 4 to 6 weeks later. RESULTS Patient recovery was characterized by a normal-appearing penis and unobstructed urinary flow. Definite depilation of the neoglans was required in 17.6% of cases. Partial necrosis of 2 flaps (5.8%) required grafts. Sexual potency was preserved in 7 men (20.5%). In 1 case (2.9%) urethral meatal stenosis resolved with minor surgical procedures. CONCLUSIONS This technique enables us to design a neoglans with acceptable function and appearance, no penile retraction, satisfactory voiding and in certain cases possible intercourse with vaginal penetration.
The Aging Male | 2010
Halina Grosman; Bibiana Fabre; Viviana Mesch; Miguel A. López; Laura Schreier; Osvaldo Mazza; Gabriela Berg
Objective. To evaluate lipoprotein profile and sex hormones in patients with prostate cancer (PCa) and benign prostatic hyperplasia (BPH) and their possible associations with some inflammatory markers linked to PCa. Methods. A total of 150 men (50–65 years), matched by age and body mass index (BMI), included in this study and divided into three groups according to total prostate specific antigen (PSA), digital rectal examination and prostate biopsy: 50 PCa, 50 BPH and 50 controls. Total cholesterol (Chol), HDL-chol, LDL-chol, triglycerides (TG), total testosterone (T), free T (FT), bioavailable T (BioT), estradiol and SHBG were measured. The free androgen index (FAI) and TG/HDL-chol were calculated. In 25 PCa and 25 controls, C-reactive protein (hs-CRP), adiponectin and insulin were determined. Results. Patients with PCa showed higher TG/HDL-chol and diminished HDL-chol than Controls and BPH. PSA correlated inversely with HDL-chol and directly with TG/HDL-chol. FAI, FT, BioT and estradiol levels were higher, and SHBG and adiponectin were lower in PCa than in Controls. No differences were found in androgens between BPH and PCa. Conclusion. Our most novel findings are that the patients with PCa presented lower total Chol and HDL-chol and higher TG/HDL-chol than BPH and Controls. Patients with PCa showed higher androgens and lower adiponectin than Controls.
The Journal of Sexual Medicine | 2006
Osvaldo Mazza; Margarita Angerosa; Edgardo Becher; Jorge E. Toblli
INTRODUCTION Previous studies indicate that angiotensin type I receptor antagonists present a beneficial effect on penile structures in hypertensive rats. However, at present there is no substantial information concerning the functional aspect of this class of antihypertensive drugs. AIM To determine, by in vitro studies, functional effects of Candesartan in comparison with a traditional vasodilating agent, Hydralazine, on penile structures in a rat model of arterial hypertension. METHODS During 4 months, three groups of male spontaneously hypertensive rats (SHR) and one of Wistar-Kyoto (WKY) rats, as control group, were studied: SHR without treatment; SHR with Candesartan cilexetil 7.5 mg/kg/day; SHR with Hydralazine 50 mg/kg/day; and WKY rats without treatment. Cavernous smooth muscle strips were mounted in an organ bath system for in vitro studies. In addition, cavernous smooth muscle and vascular smooth muscle from cavernous arteries, cavernous tissue fibrosis, and collagen type III were also evaluated by immunohistochemistry. RESULTS After 4 months, SHR with Candesartan and Hydralazine showed similar reduction in blood pressure compared with untreated SHR. However, in vitro studies revealed that SHR with Candesartan displayed a better relaxation response to acetylcholine than SHR and SHR with Hydralazine (P < 0.01). Immunostaining indicates that only SHR with Candesartan and control WKY rats showed significantly lower values of: (i) cavernous smooth muscle (P < 0.01); (ii) vascular smooth muscle (P < 0.01); and (iii) collagen type III (P < 0.01) when compared with untreated SHR or SHR with Hydralazine. Additionally, SHR with Candesartan presented a higher endothelial nitric oxide synthase expression in sinusoidal endothelium in comparison with SHR, and SHR with Hydralazine (P < 0.01). CONCLUSION Candesartan presented equivalent blood pressure control compared with Hydralazine. However, only Candesartan showed a significant better response to acetylcholine, in in vitro studies, with a protective role against structural changes in vessels as well as in cavernous spaces of the erectile tissue.
The Aging Male | 2014
Halina Grosman; Mónica Rosales; Bibiana Fabre; Carlos Nolazco; Osvaldo Mazza; Gabriela Berg; Viviana Mesch
Abstract Objective: To evaluate the relationship between testosterone levels and the metabolic syndrome (MS) in men older than 45 years. Methods: Six hundred and sixty men (45–70 years) selected from 2906 participants of a population screening for prostate cancer were included in this study. Testosterone and the components of MS were assessed in all men. MS was diagnosed according to NCEP-ATP III criteria. Triglycerides (TG)/HDL-cholesterol (chol) index was calculated. Results: The presence of MS was inversely associated with testosterone (χ2, p < 0.001), independently of age (OR 0.802, CI 95%: 0.724–0.887, p < 0.0001). Hypertension was the most frequent abnormality observed followed by elevated TG and waist circumference (WC). Testosterone correlated positively with HDL-chol (r: 0.14, p < 0.0001) and negatively with body mass index (BMI)(r: −0.29, p < 0.0001), WC (r: −0.26, p < 0.0001), TG (r: −0.20, p < 0.0001), TG/HDL-chol (r: −0.20, p < 0.0001), glucose (r: −0.11, p = 0.005) and MS score (r: −0.23, p < 0.0001). Conclusions: Our results show that in men older than 45 years, as long as testosterone levels decline, the prevalence of MS increases, independently of age. The correlations found between testosterone and four of the five components of MS, as well as with BMI and TG/HDL-chol ratio, a surrogate marker of insulin resistance, suggest considering male hypogonadism as a determinant of developmental abnormalities typical of MS.
Cellular Physiology and Biochemistry | 2012
Paula Alejandra Sacca; Virginia Pistone Creydt; Hosoon Choi; Osvaldo Mazza; Sabrina Johanna Fletcher; Valeria Beatriz Fernández Vallone; Carlos H. Scorticati; Norma Alejandra Chasseing; Juan Carlos Calvo
Background/Aims: Adipose microenvironment is involved in signaling pathways that influence prostate cancer (PCa) progression. However, the role of human periprostatic adipose tissue (PPAT) from patients with benign prostatic hyperplasia (BPH) has not been studied and compared to that of PPAT from PCa patients. The aim of this paper was to investigate the influence of factors derived from both PPATs on the behavior of androgen-dependent and castration resistant PCa cells. Methods: PPAT conditioned media (CM) were obtained from tissue samples from patients with clinically primary PCa (TPPAT) or BPH (BPPAT). Cell adhesion, proliferation, migration and metalloproteinase expression were evaluated following exposure of LNCaP (androgen dependent) and PC3 (androgen independent) prostate cancer cell lines to BPPAT or TPPAT CM. Results: Proliferation or motility of LNCaP or PC3 cells were not significantly affected by TPPAT or BPPAT CM. The number of LNCaP but not PC3 cells attached to components of TPPAT CM significantly decreased compared to cells attached to BPPAT CM. PPAT produced and released pro-MMP-9. Zymograms demonstrated that TPPAT CM induced a significant increase in pro-MMP-9 activity compared to BPPAT CM in LNCaP cells but not in PC3 cells. Conclusions: We conclude that TPPAT released factors, such as pro-MMP-9, could induce the invasive capacity of LNCaP cells and speculate that PPAT derived factors could, in the early stages of prostate cancer, modulate disease progression.
The Aging Male | 2016
Halina Grosman; Bibiana Fabre; Miguel A. López; Scorticati C; Lopez Silva M; Mesch; Osvaldo Mazza; Gabriela Berg
Abstract Objectives: To assess sex hormones, leptin and insulin-resistance in men with prostate cancer (PCa) and benign prostatic hyperplasia (BPH) and to study associations between androgens and histologic score of prostate tissue in PCa. Subjects and methods: Two hundred ten men older than 45 years selected from 2906 participants of a population screening for PCa were studied: 70 with PCa, 70 with BPH and 70 controls (CG), matched by body mass index and age. Insulin, IGF-1, PSA, leptin, total, free (fT) and bioavailable testosterone (bT) and estradiol were measured. Each group was subdivided into two subgroups considering the presence of metabolic syndrome (MS); androgens and leptin levels were analyzed in the subgroups. Results: Prostate cancer and BPH patients presented higher total, fT and bT levels than CG. IGF-1, insulin and HOMA index were higher in BPH than in the other two groups. PCa presented higher leptin [median (range) 6.5 (1.3–28.0) versus 4.8 (1.1–12.3) ng/ml; p < 0.01] and estradiol [median (range) 37.0 (20–90) versus 29.0 (20–118) pg/ml; p = 0.025] levels than CG. After dividing men considering the presence of MS, leptin was higher and total testosterone was lower in MS patients in all the groups. Conclusions: It was observed a coexistence of an altered hormone profile with increased sex hormones and leptin in PCa patients, in accordance with the new perspective of PCa pathogenesis.
Stress | 2013
Bibiana Fabre; Halina Grosman; Osvaldo Mazza; Carlos Nolazco; Nahuel Fernandez Machulsky; Viviana Mesch; Laura Schreier; Yori Gidron; Gabriela Berg
Psychological factors and stressful life events (LE) are considered to play a role in the onset of the metabolic syndrome (MS). We tested the association between LE and cortisol, a marker of chronic stress, with the risk of developing MS and their interaction. From a total number of 2906 men who completed a screening for the early detection of prostate cancer, 149 healthy men (mean ± SD age, 58.6 ± 7.7 years) were included in this study. Participants were assessed by the Holmes and Rahe questionnaire about their experience of LE during the previous 1–5 years. MS was diagnosed according to National Cholesterol Education Program-Adult Treatment Panel III (ATP-III) and International Diabetes Federation (IDF) criteria. Serum cortisol was measured at 08:00–09:00 h. Participants with MS (IDF criteria) reported significantly more past LE (p = 0.009) and greater summed weight of LE (p = 0.049) than those without MS. Furthermore, LE interacted with cortisol in relation to MS: in men with increased serum cortisol levels ( ≥ 13.7 μg/dl), number of LE significantly predicted MS-status (relative risk (RR) = 1.16, p = 0.03), whereas in men with low cortisol, LE were unrelated to MS (p = 0.52). We conclude that LE were significantly more prevalent in men with the MS than without the MS, according to IDF criteria, independent of the effects of age and body mass index, especially in men with increased serum cortisol levels.