Evidence that AKT and GSK-3β pathway are involved in acute hyperhomocysteinemia

Homocysteine is a neurotoxic amino acid that accumulates in several disorders including homocystinuria, neurodegenerative and neuroinflammatory diseases. In the present study we evaluated the effect of acute and chronic hyperhomocysteinemia on Akt, NF-κB/p65, GSK-3β, as well as Tau protein in hippocampus of rats. For acute treatment, rats received a single injection of homocysteine (0.6 μmol/g body weight) or saline (control). For chronic treatment, rats received daily subcutaneous injections of homocysteine (0.3-0.6 μmol/g body weight) or saline (control) from the 6th to the 28th days-of-age. One or 12h after the last injection, rats were euthanized, the hippocampus was removed and samples were submitted to electrophoresis followed by Western blotting. Results showed that acute hyperhomocysteinemia increases Akt phosphorylation, cytosolic and nuclear immunocontent of NF-κB/p65 subunit and Tau protein phosphorylation, but reduces GSK-3β phosphorylation at 1h after homocysteine injection. However, 12h after acute hyperhomocysteinemia there is no effect on Akt and GSK-3β phosphorylation. Furthermore, chronic hyperhomocysteinemia did not alter Akt and GSK-3β phosphorylation at 1h and 12h after the last administration of this amino acid. Our data showed that Akt, NF-κB/p65, GSK-3β and Tau protein are activated in hippocampus of rats subjected to acute hyperhomocysteinemia, suggesting that these signaling pathways may be, at least in part, important contributors to the neuroinflammation and/or brain dysfunction observed in some hyperhomocystinuric patients.     

Heart remodeling produced by aortic stenosis promotes cardiomyocyte apoptosis mediated by collagen V imbalance

Cardiac remodeling (CR) is a structural change of the heart due to chronic hemodynamic overload related to changes in both myocyte and extracellular matrix (ECM). We investigated that the imbalance of collagen V promotes cardiomyocyte apoptosis that contributes to heart failure and cell death. Aortic stenosis was induced surgically and male Wistar rats were randomized to 18 weeks (Sham 18?w, n?=?12; AoS 18?w, n?=?12) and severe of heart failure (Sham HF, n?=?12; AoS HF, n?=?12) groups. Functional and structural echocardiogram, immunohistochemistry for Ki-67, TUNEL assay and Immunofluorescence for collagen were performed. Our main results were: (1) Progressive reduction of cardiac functional capacity due to cardiac remodeling with decreased eject fraction in heart failure; (2) Imbalance of collagen deposition with increased, crowded and irregular collagen I in situ expression; (3) Dysregulation of dynamic control of collagen fibers with exposed epitopes of collagen V; (4) Additional apoptosis that are dependent to cardiac injury. The collagen V expression in cardiac remodeling is for the first time described and may be related to additional apoptosis and autoimmune response. Our findings suggest a critical role of collagen V in cardiac remodeling to modulate and promote heart failure and death.     

DFNB74, a novel autosomal recessive nonsyndromic hearing impairment locus on chromosome 12q14.2-q15

Autosomal recessive nonsyndromic hearing impairment (ARNSHI) segregating in three unrelated, large consanguineous Pakistani families (PKDF528, PKDF859 and PKDF326) is linked to markers on chromosome 12q14.2-q15. This novel locus is designated DFNB74 . Maximum two-point limit of detection (LOD) scores of 5.6, 5.7 and 2.6 were estimated for markers D 12 S 313, D 12 S 83 and D 12 S 75 at θ = 0 for recessive deafness segregating in these three families. Haplotype analyses identified a critical linkage interval of 5.35 cM (5.36 Mb) defined by D 12 S 329 at 74.58 cM and D 12 S 313 at 79.93 cM. DFNB74 is the second ARNSHI locus mapped to chromosome 12, but the physical intervals do not overlap with one another. A locus contributing to the early onset, rapidly progressing hearing loss of A/J mice ( ahl4 , age-related hearing loss 4) was reported to map to chromosome 10 in a region of conserved synteny to DFNB74 , suggesting that ahl4 and DFNB74 may be due to mutations of the same gene in these two species.     

Clinical and Genetic Predictors of Priapism in Sickle Cell Disease: Results from the Recipient Epidemiology and Donor Evaluation Study III Brazil Cohort Study

IntroductionPriapism is the persistent and painful erection of the penis and is a common sickle cell disease (SCD) complication.AimThe goal of this study was to characterize clinical and genetic factors associated with priapism within a large multi-center SCD cohort in Brazil.MethodsCases with priapism were compared to SCD type-matched controls within defined age strata to identify clinical outcomes associated with priapism. Whole blood single nucleotide polymorphism genotyping was performed using a customized array, and a genome-wide association study (GWAS) was conducted to identify single nucleotide polymorphisms associated with priapism.Main Outcome MeasureOf the 1,314 male patients in the cohort, 188 experienced priapism (14.3%).ResultsPriapism was more common among older patients (P = .006) and more severe SCD genotypes such as homozygous SS (P < .0001). In the genotype- and age-matched analyses, associations with priapism were found for pulmonary hypertension (P = .05) and avascular necrosis (P = .01). The GWAS suggested replication of a previously reported candidate gene association of priapism for the gene transforming growth factor beta receptor 3 (TGFBR3) (P = 2 × 10^?4).Clinical ImplicationsOlder patients with more severe genotypes are at higher risk of priapism, and there is a lack of consensus on standard treatment strategies for priapism in SCD.Strengths & LimitationsThis study characterizes SCD patients with any history of priapism from a large multi-center cohort. Replication of the GWAS in an independent cohort is required to validate the results.ConclusionThese findings extend the understanding of risk factors associated with priapism in SCD and identify genetic markers to be investigated in future studies to further elucidate priapism pathophysiology.Ozahata M, Page GP, Guo Y, et al. Clinical and Genetic Predictors of Priapism in Sickle Cell Disease: Results from the Recipient Epidemiology and Donor Evaluation Study III Brazil Cohort Study. J Sex Med 2019;16:1988–1999.     

Characterization of human papillomavirus genotypes and HPV-16 physical status in cervical neoplasias of women from northern Portugal

Objective

To determine human papillomavirus (HPV) genotypes and the physical status of HPV-16 DNA among women from northern Portugal with cervical lesions.

Methods

The present retrospective study included samples of cervical exfoliated cells from 88 women (median age 42.0 ± 13.1 years) who attended the Gynecology Service at the Portuguese Institute of Oncology in Porto during 2010. After DNA extraction, HPV genotyping was performed by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism analysis using the MY09/MY11 primers. The physical status of HPV-16 was determined by real-time PCR.

Results

Overall, 69.3% of the samples tested positive. The prevalence of HPV infection was 38.5% in normal samples, 57.7% in cervicitis samples, and 87.2% in all cervical lesions including invasive cancers. Sixteen genotypes were detected, the most prevalent ones being HPV-16 (42.9%), HPV-31 (12.2%), and HPV-58 (10.2%); HPV-18 was rare. The overall prevalence of HPV-16 integration was 31.6%. The physical status of HPV-16 did not differ significantly by histology.

Conclusion

The most frequent genotypes were HPV-16, -31, and -58. Integration of HPV-16 DNA seemed to be an early event in cervical carcinogenesis. Further studies are required to clarify the value of viral integration as a prognostic marker.