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7 result(s) for "Antoniassi, Mariana Pereira"
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Systemic arterial hypertension leads to decreased semen quality and alterations in the testicular microcirculation in rats
Arterial hypertension is a cardiovascular disease that leads to important systemic alterations and drastically impairs normal organ function over time. Hypertension affects around 700 million men of reproductive age and hypertensive men present increased risk for reproductive disorders, such as erectile dysfunction. However, the link between arterial hypertension and male reproductive disorders is associative at best. Moreover, many studies have reported associations between decreased male fertility and/or semen quality and alterations to general male health. In this study we aim to investigate the effect of systemic high blood pressure in sperm quality, sperm functional characteristics and testicular physiology in a rat model. Hypertensive rats presented altered testicular morphology – mainly vascular alterations and impaired testicular vasomotion. Hypertensive rats also presented decrease in sperm concentration, DNA integrity and increased percentages of sperm with dysfunctional mitochondria, intracellular superoxide anion activity and abnormal morphology. This study provides mechanistic insights by which arterial hypertension affects the testes, evidencing the testes as another target organ for hypertension as well as its impact on sperm quality.
Author Correction: Semen levels of matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinases (TIMP) protein families members in men with high and low sperm DNA fragmentation
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Semen levels of matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinases (TIMP) protein families members in men with high and low sperm DNA fragmentation
Matrix Metalloproteinases (MMPs) and their regulators – Tissue Inhibitors of Matrix Metalloproteinases (TIMPs) – participate in extracellular matrix remodeling, fibrosis, and semen liquefaction, as well as to inflammatory activity. Seminal plasma has been shown to contain MMPs (MMP-2 and MMP-9) and TIMPs (TIMP-1 and TIMP-2). Also, a link between MMPs gene expression and excessive reactive oxygen species (ROS) has been established. In semen, ROS are associated with altered sperm function and increased DNA fragmentation. In this study, it is hypothesized that seminal MMPs and TIMPs levels are associated with sperm DNA fragmentation due to the fact that MMPs have been associated with semen quality. We also hypothesized that these proteins could predict DNA fragmentation status in sperm. Therefore, this study set out to verify if sperm DNA fragmentation levels relate to seminal levels of members of the MMP and TIMP protein families. The High sperm DNA fragmentation group presented lower seminal plasma levels of MMP-2, MMP-7, TIMP-1, TIMP-2 and TIMP-4 when compared to Low sperm DNA fragmentation group. Also, samples in the high sperm DNA fragmentation group presented higher acrosome integrity and lower mitochondrial activity levels when compared to low sperm DNA fragmentation samples. In the logistic regression analysis, MMP-2, MMP-7, and TIMP-4 classified samples as low and high sperm DNA fragmentation, with an overall model fit of 74.5%. Results from this study may demonstrate a specific inflammatory mechanism in samples with high sperm DNA fragmentation. This, in turn, can lead to the development of new studies regarding this mechanism and, in the future, create an opportunity to treat these patients for sperm DNA fragmentation by treating inflammatory seminal activity.
Semen levels of matrix metalloproteinase (MMP) and tissue inhibitor of metallorproteinases (TIMP) protein families members in men with high and low sperm DNA fragmentation
Matrix Metalloproteinases (MMPs) and their regulators - Tissue Inhibitors of Matrix Metalloproteinases (TIMPs) - participate in extracellular matrix remodeling, fibrosis, and semen liquefaction, as well as to inflammatory activity. Seminal plasma has been shown to contain MMPs (MMP-2 and MMP-9) and TIMPs (TIMP-1 and TIMP-2). Also, a link between MMPs gene expression and excessive reactive oxygen species (ROS) has been established. In semen, ROS are associated with altered sperm function and increased DNA fragmentation. In this study, it is hypothesized that seminal MMPs and TIMPs levels are associated with sperm DNA fragmentation due to the fact that MMPs have been associated with semen quality. We also hypothesized that these proteins could predict DNA fragmentation status in sperm. Therefore, this study set out to verify if sperm DNA fragmentation levels relate to seminal levels of members of the MMP and TIMP protein families. The High sperm DNA fragmentation group presented lower seminal plasma levels of MMP-2, MMP-7, TIMP-1, TIMP-2 and TIMP-4 when compared to Low sperm DNA fragmentation group. Also, samples in the high sperm DNA fragmentation group presented higher acrosome integrity and lower mitochondrial activity levels when compared to low sperm DNA fragmentation samples. In the logistic regression analysis, MMP-2, MMP-7, and TIMP-4 classified samples as low and high sperm DNA fragmentation, with an overall model fit of 74.5%. Results from this study may demonstrate a specific inflammatory mechanism in samples with high sperm DNA fragmentation. This, in turn, can lead to the development of new studies regarding this mechanism and, in the future, create an opportunity to treat these patients for sperm DNA fragmentation by treating inflammatory seminal activity.
Alterations in the proliferative/apoptotic equilibrium in semen of adolescents with varicocele
Purpose To verify if the presence of varicocele (grades II and III) with and without seminal alterations, using the 5 th centile cutoff values in table A1.1 of the World Health Organization (WHO, 2010) manual, alters the seminal plasma levels of proteins DNASE1 (deoxyribonuclease-1) and IGFBP7 (Insulin-like growth factor-binding protein 7), which are related to apoptosis regulation and cell proliferation, respectively, demonstrating that these proteins are important for correct spermatogenesis. Methods This cross sectional study was performed at the Sao Paulo Federal University Paulo between May 2014 and April 2016. A total of 61 male adolescents were included in this study, of which 20 controls without varicocele (C), 22 with varicocele and normal semen analysis (VNS) and 19 with varicocele and altered semen analysis (VAS). Seminal plasma from each patient was used for Western blotting analysis of individual protein levels. Values of each protein were normalized to a testicular housekeeping protein (PARK7—protein deglycase DJ-1). Results Levels of IGFBP7 protein are increased in varicocele. Levels of DNASE1 are progressively decreased in varicocele (lower in varicocele and normal semen analysis, lowest in varicocele and altered semen analysis) when compared to adolescents without varicocele. DNASE1 levels are positively correlated with sperm concentration and morphology (correlation values of 0.400 and 0.404, respectively; p values of 0.001 and 0.001, respectively). Conclusion In conclusion, in adolescents, seminal plasma levels of IGFBP7, responsible for proliferative activity, are increased in varicocele grades II and III, and DNASE1, responsible for apoptosis regulation, are lower in varicocele, lowest in varicocele and low semen quality. These proteins demonstrate molecular alterations brought upon by varicocele. Moreover, DNASE1 is capable of discriminating a varicocele that causes alterations to semen quality from one that does not. We propose that the initial response of varicocele is to increase proliferative activity which, if followed by regulation of apoptosis, may lead to the ejaculation of a population of sperm that are in accordance with WHO cutoff values but, in the presence of dysregulated apoptosis, leads to lower sperm concentration and morphology.
Restoration of the apoptosis pathways’ proteins levels after orchiectomy in testicular tumour patients
Seminal plasma proteins already demonstrated to reflect the testicular environment function and important regulatory mechanisms. However, it is crucial to understand which of these proteins participate in probable altered pathways in testicular germ cell tumours and after unilateral orchiectomy. In this study, we proposed to verify, by a multiplex approach, the levels of DNA damage and apoptosis pathways’ proteins, in seminal plasma of men before and after unilateral orchiectomy, and also in control men. Comparing pre‐ and post‐orchiectomy groups, just the apoptosis pathways’ proteins presented different levels, in which Bad was lower and Bcl2, Akt, caspase‐9, p53 and caspase‐8 were higher after orchiectomy. When comparing pre‐ and post‐orchiectomy groups with control, both presented lower levels of ChK1, Chk2, H2AX, p53 and p21, for DNA damage pathway. Regarding the apoptosis pathway, lower levels of JNK, Bcl2, Akt, caspase‐9, p53 and caspase‐8 and higher levels of Bad were observed before orchiectomy. The post‐orchiectomy group did not differ from controls, demonstrating a probable restoration on its proteins levels. We can conclude that testicular tumours can alter both of the assessed pathways, and its removal is associated with a probable restoration of the apoptosis pathway.