Antiapoptotic Factor Humanin Is Expressed in Normal and Tumoral Pituitary Cells and Protects Them from TNF-α-Induced Apoptosis

Humanin (HN) is a 24-amino acid peptide with cytoprotective action in several cell types such as neurons and testicular germ cells. Rattin (HNr), a homologous peptide of HN expressed in several adult rat tissues, also has antiapoptotic action. In the present work, we demonstrated by immunocytochemical analysis and flow cytometry the expression of HNr in the anterior pituitary of female and male adult rats as well as in pituitary tumor GH3 cells. HNr was localized in lactotropes and somatotropes. The expression of HNr was lower in females than in males, and was inhibited by estrogens in pituitary cells from both ovariectomized female and orquidectomized male rats. However, the expression of HNr in pituitary tumor cells was not regulated by estrogens. We also evaluated HN action on the proapoptotic effect of TNF-α in anterior pituitary cells assessed by the TUNEL method. HN (5 µM) per se did not modify basal apoptosis of anterior pituitary cells but completely blocked the proapoptotic effect of TNF-α in total anterior pituitary cells, lactotropes and somatotropes from both female and male rats. Also, HN inhibited the apoptotic effect of TNF-α on pituitary tumor cells. In summary, our results demonstrate that HNr is present in the anterior pituitary gland, its expression showing sexual dimorphism, which suggests that gonadal steroids may be involved in the regulation of HNr expression in this gland. Antiapoptotic action of HN in anterior pituitary cells suggests that this peptide could be involved in the homeostasis of this gland. HNr is present and functional in GH3 cells, but it lacks regulation by estrogens, suggesting that HN could participate in the pathogenesis of pituitary tumors.     

Prevalence of Abdominal Obesity in Spanish Children and Adolescents. Do We Need Waist Circumference Measurements in Pediatric Practice?

Background

Evidence indicates that central adiposity has increased to a higher degree than general adiposity in children and adolescents in recent decades. However, waist circumference is not a routine measurement in clinical practice.

Objective

This study aimed to determine the prevalence of abdominal obesity based on waist circumferences (WC) and waist to height ratio (WHtR) in Spanish children and adolescents aged 6 to 17 years. Further, the prevalence of abdominal obesity (AO) among normal and overweight individuals was analyzed.

Design

Data were obtained from a study conducted from 1998 to 2000 in a representative national sample of 1521 children and adolescents aged 6 to 17 years (50.0% female) in Spain. WC and WHtR measurements were obtained in addition to BMI. AO was defined as WHtR ≥0.50 (WHtR-AO), sex and age specific WC≥90^th percentile (WC-AO1), and sex and age specific WC cut-off values associated with high trunk fat measured by by dual-energy X-ray absorptiometry (WC-AO2).

Results

IOTF- based overweight and obsity prevalence was 21.5% and 6.6% in children and 17.4% and 5.2% in adolescents, respectively. Abdominal obesity (AO) was defined as WHtR≥0.50 (WHtR-AO), sex- and age-specific WC≥90th percentile (WC-AO1), and sex- and age-specific WC cut-off values associated with high trunk fat measured by dual-energy X-ray absorptiometry (WC-AO2). The respective prevalence of WHtR-AO, WC-AO1, and WC-AO2 was 21.3% (24.6% boys; 17.9% girls), 9.4% (9.1% boys; 9.7% girls), and 26.8% (30.6% boys;22.9% girls) in children and 14.3% (20.0% boys; 8.7% girls), 9.6% (9.8% boys; 9.5% girls), and 21.1% (28.8% boys; 13.7% girls) in adolescents.

Conclusion

The prevalence of AO in Spanish children and adolescents is of concern. The high proportion of AO observed in young patients who are normal weight or overweight indicates a need to include waist circumference measurements in routine clinical practice.     

Activation of Mu Opioid Receptors Sensitizes Transient Receptor Potential Vanilloid Type 1 (TRPV1) via β-Arrestin-2-Mediated Cross-Talk

The transient receptor potential family V1 channel (TRPV1) is activated by multiple stimuli, including capsaicin, acid, endovanilloids, and heat (>42C). Post-translational modifications to TRPV1 result in dynamic changes to the sensitivity of receptor activation. We have previously demonstrated that β-arrestin2 actively participates in a scaffolding mechanism to inhibit TRPV1 phosphorylation, thereby reducing TRPV1 sensitivity. In this study, we evaluated the effect of β-arrestin2 sequestration by G-protein coupled receptors (GPCRs) on thermal and chemical activation of TRPV1. Here we report that activation of mu opioid receptor by either morphine or DAMGO results in β-arrestin2 recruitment to mu opioid receptor in sensory neurons, while activation by herkinorin does not. Furthermore, treatment of sensory neurons with morphine or DAMGO stimulates β-arrestin2 dissociation from TRPV1 and increased sensitivity of the receptor. Conversely, herkinorin treatment has no effect on TRPV1 sensitivity. Additional behavioral studies indicate that GPCR-driven β-arrestin2 sequestration plays an important peripheral role in the development of thermal sensitivity. Taken together, the reported data identify a novel cross-talk mechanism between GPCRs and TRPV1 that may contribute to multiple clinical conditions.     

Decay-Accelerating Factor 1 Deficiency Exacerbates Leptospiral-Induced Murine Chronic Nephritis and Renal Fibrosis

Leptospirosis is a global zoonosis caused by pathogenic Leptospira, which can colonize the proximal renal tubules and persist for long periods in the kidneys of infected hosts. Here, we characterized the infection of C57BL/6J wild-type and Daf1^−/− mice, which have an enhanced host response, with a virulent Leptospira interrogans strain at 14 days post-infection, its persistence in the kidney, and its link to kidney fibrosis at 90 days post-infection. We found that Leptospira interrogans can induce acute moderate nephritis in wild-type mice and is able to persist in some animals, inducing fibrosis in the absence of mortality. In contrast, Daf1^−/− mice showed acute mortality, with a higher bacterial burden. At the chronic stage, Daf1^−/− mice showed greater inflammation and fibrosis than at 14 days post-infection and higher levels at all times than the wild-type counterpart. Compared with uninfected mice, infected wild-type mice showed higher levels of IL-4, IL-10 and IL-13, with similar levels of α-smooth muscle actin, galectin-3, TGF-β1, IL-17, IFN-γ, and lower IL-12 levels at 90 days post-infection. In contrast, fibrosis in Daf1^−/− mice was accompanied by high expression of α-smooth muscle actin, galectin-3, IL-10, IL-13, and IFN-γ, similar levels of TGF-β1, IL-12, and IL-17 and lower IL-4 levels. This study demonstrates the link between Leptospira-induced murine chronic nephritis with renal fibrosis and shows a protective role of Daf1.     

Mycoplasma pneumoniae CARDS Toxin Exacerbates Ovalbumin-Induced Asthma-Like Inflammation in BALB/c Mice

Mycoplasma pneumoniae causes a range of airway and extrapulmonary pathologies in humans. Clinically, M. pneumoniae is associated with acute exacerbations of human asthma and a worsening of experimentally induced asthma in mice. Recently, we demonstrated that Community Acquired Respiratory Distress Syndrome (CARDS) toxin, an ADP-ribosylating and vacuolating toxin synthesized by M. pneumoniae, is sufficient to induce an asthma-like disease in BALB/cJ mice. To test the potential of CARDS toxin to exacerbate preexisting asthma, we examined inflammatory responses to recombinant CARDS toxin in an ovalbumin (OVA) murine model of asthma. Differences in pulmonary inflammatory responses between treatment groups were analyzed by histology, cell differentials and changes in cytokine and chemokine concentrations. Additionally, assessments of airway hyperreactivity were evaluated through direct pulmonary function measurements. Analysis of histology revealed exaggerated cellular inflammation with a strong eosinophilic component in the CARDS toxin-treated group. Heightened T-helper type-2 inflammatory responses were evidenced by increased expression of IL-4, IL-13, CCL17 and CCL22 corresponding with increased airway hyperreactivity in the CARDS toxin-treated mice. These data demonstrate that CARDS toxin can be a causal factor in the worsening of experimental allergic asthma, highlighting the potential importance of CARDS toxin in the etiology and exacerbation of human asthma.     

Safety of Hormonal Replacement Therapy and Oral Contraceptives in Systemic Lupus Erythematosus: A Systematic Review and Meta-Analysis

Background

There is conflicting data regarding exogenous sex hormones [oral contraceptives (OC) and hormonal replacement therapy (HRT)] exposure and different outcomes on Systemic Lupus Erythematosus (SLE). The aim of this work is to determine, through a systematic review and meta-analysis the risks associated with estrogen use for women with SLE as well as the association of estrogen with developing SLE.

Methods and Findings

MEDLINE, EMBASE, SciElo, BIREME and the Cochrane library (1982 to July 2012), were databases from which were selected and reviewed (PRISMA guidelines) randomized controlled trials, cross-sectional, case-control and prospective or retrospective nonrandomized, comparative studies without language restrictions. Those were evaluated by two investigators who extracted information on study characteristics, outcomes of interest, risk of bias and summarized strength of evidence. A total of 6,879 articles were identified; 20 full-text articles were included. Thirty-two meta-analyses were developed. A significant association between HRT exposure (Random model) and an increased risk of developing SLE was found (Rate Ratio: 1.96; 95%-CI: 1.51–2.56; P-value<0.001). One of eleven meta-analyses evaluating the risk for SLE associated with OC exposure had a marginally significant result. There were no associations between HRT or OC exposure and specific outcomes of SLE. It was not always possible to Meta-analyze all the available data. There was a wide heterogeneity of SLE outcome measurements and estrogen therapy administration.

Conclusion

An association between HRT exposure and SLE causality was observed. No association was found when analyzing the risk for SLE among OC users, however since women with high disease activity/Thromboses or antiphospholipid-antibodies were excluded from most of the studies, caution should be exercised in interpreting the present results. To identify risk factors that predispose healthy individuals to the development of SLE who are planning to start HRT or OC is suggested.     

Pasteurella pneumotropica Evades the Human Complement System by Acquisition of the Complement Regulators Factor H and C4BP

Pasteurella pneumotropica is an opportunist Gram negative bacterium responsible for rodent pasteurellosis that affects upper respiratory, reproductive and digestive tracts of mammals. In animal care facilities the presence of P. pneumotropica causes severe to lethal infection in immunodeficient mice, being also a potential source for human contamination. Indeed, occupational exposure is one of the main causes of human infection by P. pneumotropica. The clinical presentation of the disease includes subcutaneous abscesses, respiratory tract colonization and systemic infections. Given the ability of P. pneumotropica to fully disseminate in the organism, it is quite relevant to study the role of the complement system to control the infection as well as the possible evasion mechanisms involved in bacterial survival. Here, we show for the first time that P. pneumotropica is able to survive the bactericidal activity of the human complement system. We observed that host regulatory complement C4BP and Factor H bind to the surface of P. pneumotropica, controlling the activation pathways regulating the formation and maintenance of C3-convertases. These results show that P. pneumotropica has evolved mechanisms to evade the human complement system that may increase the efficiency by which this pathogen is able to gain access to and colonize inner tissues where it may cause severe infections.     

Integrated Proteomics Identified Up-Regulated Focal Adhesion-Mediated Proteins in Human Squamous Cell Carcinoma in an Orthotopic Murine Model

Understanding the molecular mechanisms of oral carcinogenesis will yield important advances in diagnostics, prognostics, effective treatment, and outcome of oral cancer. Hence, in this study we have investigated the proteomic and peptidomic profiles by combining an orthotopic murine model of oral squamous cell carcinoma (OSCC), mass spectrometry-based proteomics and biological network analysis. Our results indicated the up-regulation of proteins involved in actin cytoskeleton organization and cell-cell junction assembly events and their expression was validated in human OSCC tissues. In addition, the functional relevance of talin-1 in OSCC adhesion, migration and invasion was demonstrated. Taken together, this study identified specific processes deregulated in oral cancer and provided novel refined OSCC-targeting molecules.     

Use of Third Line Antiretroviral Therapy in Latin America

Background

Access to highly active antiretroviral therapy (HAART) is expanding in Latin America. Many patients require second and third line therapy due to toxicity, tolerability, failure, or a combination of factors. The need for third line HAART, essential for program planning, is not known.

Methods

Antiretroviral-naïve patients ≥18 years who started first HAART after January 1, 2000 in Caribbean, Central and South America Network (CCASAnet) sites in Argentina, Brazil, Honduras, Mexico, and Peru were included. Clinical trials participants were excluded. Third line HAART was defined as use of darunavir, tipranavir, etravirine, enfuvirtide, maraviroc or raltegravir. Need for third line HAART was defined as virologic failure while on second line HAART.

Results

Of 5853 HAART initiators followed for a median of 3.5 years, 310 (5.3%) failed a second line regimen and 44 (0.8%) received a third line regimen. Cumulative incidence of failing a 2nd or starting a 3rd line regimen was 2.7% and 6.0% three and five years after HAART initiation, respectively. Predictors at HAART initiation for failing a second or starting a third line included female sex (hazard ratio [HR] = 1.54, 95% confidence interval [CI] 1.18–2.00, p = 0.001), younger age (HR = 2.76 for 20 vs. 40 years, 95% CI 1.86–4.10, p<0.001), and prior AIDS (HR = 2.17, 95% CI 1.62–2.90, p<0.001).

Conclusions

Third line regimens may be needed for at least 6% of patients in Latin America within 5 years of starting HAART, a substantial proportion given the large numbers of patients on HAART in the region. Improved accessibility to third line regimens is warranted.     

Avian Influenza Virus (H11N9) in Migratory Shorebirds Wintering in the Amazon Region,Brazil

Aquatic birds are the natural reservoir for avian influenza viruses (AIV). Habitats in Brazil provide stopover and wintering sites for water birds that migrate between North and South America. The current study was conducted to elucidate the possibility of the transport of influenza A viruses by birds that migrate annually between the Northern and Southern Hemispheres. In total, 556 orotracheal/cloacal swab samples were collected for influenza A virus screening using real-time RT-PCR (rRT-PCR). The influenza A virus-positive samples were subjected to viral isolation. Four samples were positive for the influenza A matrix gene by rRT-PCR. From these samples, three viruses were isolated, sequenced and characterized. All positive samples originated from a single bird species, the ruddy turnstone (Arenaria interpres), that was caught in the Amazon region at Caeté Bay, Northeast Pará, at Ilha de Canelas. To our knowledge, this is the first isolation of H11N9 in the ruddy turnstone in South America.