Polymer-Based Nanoparticles with Probucol and Lithocholic Acid: A Novel Therapeutic Approach for Oxidative Stress-Induced Retinopathies.

Oxidative stress is pivotal in retinal disease progression, causing dysfunction in various retinal components. An effective antioxidant, such as probucol (PB), is vital to counteract oxidative stress and emerges as a potential candidate for treating retinal degeneration. However, the challenges associated with delivering lipophilic drugs such as PB to the posterior segment of the eye, specifically targeting photoreceptor cells, necessitate innovative solutions. This study uses formulation-based spray dry encapsulation technology to develop polymer-based PB-lithocholic acid (LCA) nanoparticles and assesses their efficacy in the 661W photoreceptor-like cell line. Incorporating LCA enhances nanoparticles' biological efficacy without compromising PB stability. In vitro studies demonstrate that PB-LCA nanoparticles prevent reactive oxygen species (ROS)-induced oxidative stress by improving cellular viability through the nuclear erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. These findings propose PB-LCA nanoparticles as a promising therapeutic strategy for oxidative stress-induced retinopathies.

Dual AAV-based PCDH15 gene therapy achieves sustained rescue of visual function in a mouse model of Usher syndrome 1F.

Mutations in the PCDH15 gene, encoding protocadherin-15, are among the leading causes of Usher syndrome type 1 (USH1F), and account for up to 12% USH1 cases worldwide. A founder truncating variant of PCDH15 has a ∼2% carrier frequency in Ashkenazi Jews accounting for nearly 60% of their USH1 cases. Although cochlear implants can restore hearing perception in USH1 patients, presently there are no effective treatments for the vision loss due to retinitis pigmentosa. We established a founder allele-specific Pcdh15 knockin mouse model as a platform to ascertain therapeutic strategies. Using a dual-vector approach to circumvent the size limitation of adeno-associated virus, we observed robust expression of exogenous PCDH15 in the retinae of Pcdh15KI mice, sustained recovery of electroretinogram amplitudes and key retinoid oxime, substantially improved light-dependent translocation of phototransduction proteins, and enhanced levels of retinal pigment epithelium-derived enzymes. Thus, our data raise hope and pave the way for future gene therapy trials in USH1F subjects.

Work hours, weekend working, nonstandard work schedules and sleep quantity and quality: findings from the UK household longitudinal study.

BACKGROUND: Atypical temporal work patterns such as working longer than the standard 35-40 h/ week, weekend working, and nonstandard work schedules (i.e. outside of the typical 9-5, including but not restricted to shiftwork) are increasingly prevalent in the UK. Aside from occupation-specific studies, little is known about the effects of these atypical temporal work patterns on sleep among workers in the UK, even though poor sleep has been linked to adverse health problems, lower workplace productivity, and economic costs. METHOD: We used regression models to investigate associations between three types of atypical temporal work patterns (long and short weekly work hours, weekend working, and nonstandard schedules) and sleep duration and disturbance using data from over 25,000 employed men and women from 2012-2014 and/or 2015-2017 in the UK Household Longitudinal Study, adjusting for potential confounders and psychosocial work factors. RESULTS: We found that relative to a standard 35-40 h/week, working 55 h/week or more was related to short sleep (less than 7 h/night) and sleep disturbance. Working most/all weekends compared to non-weekends was associated with short sleep, long sleep (more than 8 h/night), and sleep disturbance, as was working nonstandard schedules relative to standard schedules (fixed day-time schedules). Further analyses suggested some gender differences. CONCLUSIONS: These results should prompt employers and policymakers to recognise the need for rest and recovery, consider how the timing and scheduling of work might be improved to better support workers' health and productivity, and consider appropriate compensation for anyone required to work atypical temporal work patterns.

Natural history and biomarkers of KCNV2-associated retinopathy.

BACKGROUND: KCNV2-associated retinopathy is an autosomal recessive inherited retinal disease classically named cone dystrophy with supernormal rod response (CDSRR). This study aims to identify the best biomarker for evaluating the condition. METHODS: A retrospective review of eight patients from seven families with genetically confirmed KCNV2-associated retinopathy was performed. The best corrected visual acuity (BCVA), full-field electroretinogram (ffERG), pattern ERG (pERG), fundus imaging: retinal photograph and fundus autofluorescence (FAF), and optical coherence tomography (OCT) were analysed. RESULTS: There was a disproportionate increase in b-wave amplitude with a relatively small light intensity increase, especially between the two dimmest stimuli of DA 0.002 and 0.01 (-2.7 and -2.0 log cd.s/m2). The a-wave amplitude was normal. The a-wave peak time was delayed in all stimuli. The b-wave peak time was delayed compared to normal, but the gap tightened as intensity increased. The b:a wave ratio was above or at the upper limit for the reference values. FAF bull's eye maculopathy pattern was prominent and variable foveal disruption on OCT was apparent in all patients. Legal blindness was reached before the age of 25. CONCLUSIONS: We identified three potential electrophysiology biomarkers to assist in evaluating future therapies: the disproportionate b-wave amplitude jump, delayed a-wave and b-wave peak time, and the higher than normal b:a wave ratio. Any of these biomarkers found with photoreceptor ellipsoid zone foveal-perifoveal disruption should prompt consideration for KCNV2 retinopathy. The BCVA natural history data suggests the probable optimum therapeutic window in the first three decades of life.

A systematic review and meta-analysis of the evidence on inflammation in depressive illness and symptoms in chronic and end-stage kidney disease.

BACKGROUND: Depression affects approximately 27% of adults with chronic kidney disease (CKD) and end-stage kidney failure (ESKF). Depression in this population is associated with impaired quality of life and increased mortality. The extent of inflammation and the impact on depression in CKD/ESKF is yet to be established. Through a systematic literature review and meta-analysis, we aim to understand the relationship between depression and inflammation in CKD/ESKF patients. METHODS: We searched nine electronic databases for published studies until January 2022. Titles and abstracts were screened against inclusion and exclusion criteria. Data extraction and study quality assessment was carried out independently by two reviewers. A meta-analysis was carried out where appropriate; otherwise a narrative review of studies was completed. RESULTS: Sixty studies met our inclusion criteria and entered the review (9481 patients included in meta-analysis). Meta-analysis of cross-sectional associations revealed significantly higher levels of pro-inflammatory biomarkers; C-reactive protein; Interleukin 6 (IL-6) and tumour necrosis factor-alpha in patients with depressive symptoms (DS) compared to patients without DS. Significantly lower levels of anti-inflammatory cytokine IL-10 were found in patients with DS compared to patients without DS. Considerable heterogeneity was detected in the analysis for most inflammatory markers. CONCLUSION: We found evidence for an association of higher levels of pro-inflammatory and lower anti-inflammatory cytokines and DS in patients with CKD/ESKF. Clinical trials are needed to investigate whether anti-inflammatory therapies will be effective in the prevention and treatment of DS in these patients with multiple comorbidities.

Trajectories of health-related quality of life and their predictors in adult COVID-19 survivors: A longitudinal analysis of the Biobanque Québécoise de la COVID-19 (BQC-19).

PURPOSE: A significant number of people will experience prolonged symptoms after COVID-19 infection that will greatly impact functional capacity and quality of life. The aim of this study was to identify trajectories of health-related quality of life (HRQOL) and their predictors among adults diagnosed with COVID-19. METHODS: This is a retrospective analysis of an ongoing prospective cohort study (BQC-19) including adults (≥18y) recruited from April 2020 to March 2022. Our primary outcome is HRQOL using the EQ-5D-5L scale. Sociodemographic, acute disease severity, vaccination status, fatigue, and functional status at onset of the disease were considered as potential predictors. The latent class mixed model was used to identify the trajectories over an 18-month period in the cohort as a whole, as well as in the inpatient and outpatient subgroups. Multivariable and univariable regressions models were undertaken to detect predictors of decline. RESULTS: 2163 participants were included. Thirteen percent of the outpatient subgroup (2 classes) and 28% in the inpatient subgroup (3 classes) experienced a more significant decline in HRQOL over time than the rest of the participants. Among all patients, age, sex, disease severity and fatigue, measured on the first assessment visit or on the first day after hospital admission (multivariable models), were identified as the most important predictors of HRQOL decline. Each unit increase in the SARC-F and CFS scores increase the likelihood of belonging to the declining trajectory (univariable models). CONCLUSION: Although to different degrees, similar factors explain the decline in HRQOL over time among the overall population, people who have been hospitalized or not. Clinical functional capacity scales could help to determine the risk of HRQOL decline.

Increased H3K27 trimethylation contributes to cone survival in a mouse model of cone dystrophy.

Inherited retinal diseases (IRDs) are a heterogeneous group of blinding disorders, which result in dysfunction or death of the light-sensing cone and rod photoreceptors. Despite individual IRDs (Inherited retinal disease) being rare, collectively, they affect up to 1:2000 people worldwide, causing a significant socioeconomic burden, especially when cone-mediated central vision is affected. This study uses the Pde6ccpfl1 mouse model of achromatopsia, a cone-specific vision loss IRD (Inherited retinal disease), to investigate the potential gene-independent therapeutic benefits of a histone demethylase inhibitor GSK-J4 on cone cell survival. We investigated the effects of GSK-J4 treatment on cone cell survival in vivo and ex vivo and changes in cone-specific gene expression via single-cell RNA sequencing. A single intravitreal GSK-J4 injection led to transcriptional changes in pathways involved in mitochondrial dysfunction, endoplasmic reticulum stress, among other key epigenetic pathways, highlighting the complex interplay between methylation and acetylation in healthy and diseased cones. Furthermore, continuous administration of GSK-J4 in retinal explants increased cone survival. Our results suggest that IRD (Inherited retinal disease)-affected cones respond positively to epigenetic modulation of histones, indicating the potential of this approach in developing a broad class of novel therapies to slow cone degeneration.

Compensatory Cone-Mediated Mechanisms in Inherited Retinal Degeneration Mouse Models: A Functional and Gene Expression Analysis.

The retina undergoes compensatory changes in response to progressive photoreceptor loss/dysfunction; however, studies of inherited retinal diseases (IRDs) often lack a temporal connection between gene expression and visual function. Here, we used three mouse models of IRD - Cnga3-/-, Pde6ccpfl1, and Rd1 - to investigate over time the effect of photoreceptor degeneration, particularly cones, on visual function and gene expression. Changes to gene expression include increases in cell survival and cell death genes in Pde6ccpfl1 before significant cell loss, as well as an increase in cone-specific genes in the Rd1 at the peak of rod death. We show that Cnga3-/- and Pde6ccpfl1 mice maintained photopic visual acuity via optomotor responses, despite no recordable cone electroretinogram (ERG), while functional measures and photoreceptors loss were correlated in Rd1 mice. There were also significant changes to oscillatory potentials (OPs) in Cnga3-/- and Pde6ccpfl1, implying an effect on inner retinal cells as a result of cone degeneration. These results indicate a potentially malleable retinal environment following cone degeneration; however, further investigation is needed to elucidate how these changes compensate for the loss of cone function.

Evidence for endogenous exchange of cytoplasmic material between a subset of cone and rod photoreceptors within the adult mammalian retina via direct cell-cell connections.

Photoreceptor cell transplantation into the mouse retina has been shown to result in the transfer of cytoplasmic material between donor and host photoreceptors. Recently it has been found that this inter-photoreceptor material transfer process is likely to be mediated by nanotube-like structures connecting donor and host photoreceptors. By leveraging cone-specific reporter mice and super-resolution microscopy we provide evidence for the transfer of cytoplasmic material also from endogenous cones to endogenous rod photoreceptors and the existence of nanotube-like cell-cell connections possibly mediating this process in the adult mouse retina, together with preliminary data indicating that horizontal material transfer may also occur in the human retina.

Immunochemotherapy for visceral leishmaniasis: combinatorial action of Miltefosine plus LBSapMPL vaccine improves adaptative Th1 immune response with control of splenic parasitism in experimental hamster model.

The control of human visceral leishmaniasis (VL) is hard since there are no vaccines available as well as the treatment is hampered by toxicity and resistant parasites. Furthermore, as human, and canine VL causes immunosuppression, the combination of drugs with immunostimulatory agents is interesting to upregulate the immunity, reducing side-effects, improving treatment approaches against disease. Herein, we assessed the immunochemotherapy using miltefosine along with a vaccine formulated by Leishmania braziliensis antigens + saponin + monophosphoryl lipid-A (LBSapMPL) in L. infantum-infected hamsters. Two months after infection, the animals received treatments, and after 15 days they were evaluated for the treatment effect. The potential anti-Leishmania effect of miltefosine + LBSapMPL-vaccine was revealed by a specific immune response activation reflecting in control of spleen parasitism using half the miltefosine treatment time. The treated animals also showed an increase of total and T-CD4 splenocytes producing IFN-γ and TNF-α and a decrease of interleukin-10 and anti-Leishmania circulating IgG. In addition, it was demonstrated that the control of spleen parasitism is related to the generation of a protective Th1 immune response. Hence, due to the combinatorial action of miltefosine with LBSapMPL-vaccine in immunostimulating and controlling parasitism, this immunochemotherapy protocol can be an important alternative option against canine and human VL.

Flau-A, a naphthoquinone derivative, is a promising therapeutic candidate against visceral leishmaniasis: A preliminary study.

Visceral leishmaniasis (VL) is a neglected tropical disease found in tropical and subtropical regions in the world. The therapeutics used for the treatment against disease presents problems, mainly related to drug toxicity, route of administration, high cost and/or by emergence of resistant strains. In this context, the search for alternative antileishmanial candidates is desirable. Recently, a naphthoquinone derivative namely 2-(2,3,4-tri-O-acetyl-6-deoxy-ß-L-galactopyranosyloxy)-1,4-naphthoquinone or Flau-A showed an effective in vitro biological action against Leishmania infantum. In the present study, the efficacy of this naphthoquinone derivative was evaluated in an in vivo infection model. BALB/c mice (n = 12 per group) were infected and later received saline or were treated with empty micelles (B/Mic), free Flau-A or it incorporated in Poloxamer 407-based micelles (Flau-A/Mic). The products were administered subcutaneously in the infected animals, which were then euthanized one (n = 6 per group) and 15 (n = 6 per group) days post-therapy, when immunological and parasitological evaluations were performed. Results showed that animals treated with Flau-A or Flau-A/Mic produced significantly higher levels of antileishmanial IFN-γ, IL-12, TNF-α, GM-CSF, nitrite and IgG2a isotype antibody, when compared to data found in the control (saline and B/Mic) groups; which showed significantly higher levels of parasite-specific IL-4, IL-10 and IgG1 antibody. In addition, animals receiving free Flau-A or Flau-A/Mic presented also significant reductions in the parasite load in their spleens, livers, bone marrows and draining lymph nodes, when compared to the controls. A low hepatic and renal toxicity was also found. Overall, Flau-A/Mic showed better immunological and parasitological results, when compared to the use of free molecule. In conclusion, preliminary data suggest that this composition could be considered in future studies as promising therapeutic candidate against VL.

Clinical evaluation and ancillary testing for the diagnosis of death by neurologic criteria: a cross-sectional survey of Canadian intensivists.

PURPOSE: Trust in the deceased organ donation process relies on the expectation that the diagnosis of death by neurologic criteria (DNC) is accurate and reliable. The objective of this study was to assess the perceptions and approaches to DNC diagnosis among Canadian intensivists. METHODS: We conducted a self-administered, online, cross-sectional survey of Canadian intensivists. Our sampling frame included all intensivists practicing in Canadian institutions. Results are reported using descriptive statistics. RESULTS: Among 550 identified intensivists, 249 (45%) completed the survey. Respondents indicated they would be comfortable diagnosing DNC based on clinical criteria alone in cases where there is movement in response to stimulation (119/248; 48%); inability to evaluate upper/lower extremity responses (84/249; 34%); spontaneous peripheral movement (76/249; 31%); inability to evaluate both oculocephalic and oculo-caloric reflexes (40/249; 16%); presence of high cervical spinal cord injury (40/249; 16%); and within 24 hr of hypoxemic-ischemic brain injury (38/247; 15%). Most respondents agreed that an ancillary test should always be conducted when a complete clinical evaluation is impossible (225/241; 93%); when there is possibility of a residual sedative effect (216/242; 89%); when the mechanism for brain injury is unclear (172/241; 71%); and if isolated brainstem injury is suspected (142/242; 59%). Sixty-six percent (158/241) believed that ancillary tests are sensitive and 55% (132/241) that they are specific for DNC. Respondents considered the following ancillary tests useful for DNC: four-vessel conventional angiography (211/241; 88%), nuclear imaging (179/240; 75%), computed tomography (CT) angiography (156/240; 65%), and CT perfusion (134/240; 56%). CONCLUSION: There is variability in perceptions and approaches to DNC diagnosis among Canadian intensivists, and some practices are inconsistent with national recommendations.

RéSUMé: OBJECTIF: La confiance dans le processus de don d'organes de donneurs décédés repose sur l'attente que le diagnostic de décès déterminé par des critères neurologiques (DDN) soit précis et fiable. L'objectif de cette étude était d'évaluer les perceptions et les approches du diagnostic de DDN chez les intensivistes canadiens. MéTHODE: Nous avons mené un sondage transversal auto-administré et en ligne auprès des intensivistes canadiens. Notre base d'échantillonnage comprenait tous les intensivistes exerçant dans des établissements canadiens. Les résultats sont présentés à l'aide de statistiques descriptives. RéSULTATS: Parmi les 550 intensivistes identifiés, 249 (45 %) ont répondu au sondage. Les répondants ont indiqué qu'ils seraient à l'aise de diagnostiquer un DDN en fonction de critères cliniques seulement dans les cas où il y a : un mouvement en réponse à une stimulation (119/248; 48 %); une incapacité à évaluer les réponses des membres supérieurs et inférieurs (84/249; 34 %); un mouvement périphérique spontané (76/249; 31 %); une incapacité à évaluer à la fois les réflexes oculo-céphaliques et vestibulo-oculaires (40/249; 16 %); la présence de lésions médullaires cervicales hautes (40/249; 16 %); et dans les 24 heures suivant une lésion cérébrale hypoxémique-ischémique (38/247; 15 %). La plupart des répondants étaient d'accord pour dire qu'un test auxiliaire devrait toujours être réalisé lorsqu'une évaluation clinique complète est impossible (225/241; 93 %); lorsqu'il y a possibilité d'un effet sédatif résiduel (216/242; 89 %); lorsque le mécanisme de la lésion cérébrale n'est pas clair (172/241; 71 %); et si une lésion isolée du tronc cérébral est suspectée (142/242; 59 %). Soixante-six pour cent (158/241) des répondants étaient d'avis que les tests auxiliaires étaient sensibles et 55 % (132/241) qu'ils étaient spécifiques pour le DDN. Les répondants ont jugé utiles les tests auxiliaires suivants pour le DDN : l'angiographie conventionnelle des quatre vaisseaux (211/241; 88 %), l'imagerie nucléaire (179/240; 75 %), l'angiographie par tomodensitométrie (TDM) (156/240; 65 %) et la perfusion en TDM (134/240; 56 %). CONCLUSION: Les perceptions et les approches du diagnostic de DDN varient parmi les intensivistes canadiens, et certaines pratiques ne sont pas conformes aux recommandations nationales.

Primary and Secondary Cone Cell Death Mechanisms in Inherited Retinal Diseases and Potential Treatment Options.

Inherited retinal diseases (IRDs) are a leading cause of blindness. To date, 260 disease-causing genes have been identified, but there is currently a lack of available and effective treatment options. Cone photoreceptors are responsible for daylight vision but are highly susceptible to disease progression, the loss of cone-mediated vision having the highest impact on the quality of life of IRD patients. Cone degeneration can occur either directly via mutations in cone-specific genes (primary cone death), or indirectly via the primary degeneration of rods followed by subsequent degeneration of cones (secondary cone death). How cones degenerate as a result of pathological mutations remains unclear, hindering the development of effective therapies for IRDs. This review aims to highlight similarities and differences between primary and secondary cone cell death in inherited retinal diseases in order to better define cone death mechanisms and further identify potential treatment options.

Gene replacement therapy restores RCBTB1 expression and cilium length in patient-derived retinal pigment epithelium.

Biallelic mutations in the RCBTB1 gene cause retinal dystrophy. Here, we characterized the effects of RCBTB1 gene deficiency in retinal pigment epithelial (RPE) cells derived from a patient with RCBTB1-associated retinopathy and restored RCBTB1 expression in these cells using adeno-associated viral (AAV) vectors. Induced pluripotent stem cells derived from a patient with compound heterozygous RCBTB1 mutations (c.170delG and c.707delA) and healthy control subjects were differentiated into RPE cells. RPE cells were treated with AAV vectors carrying a RCBTB1 transgene. Patient-derived RPE cells showed reduced expression of RCBTB1. Expression of NFE2L2 showed a non-significant reduction in patient RPE cells compared with controls, while expression of its target genes (RXRA, IDH1 and SLC25A25) was significantly reduced. Trans-epithelial electrical resistance, surface microvillus densities and primary cilium lengths were reduced in patient-derived RPE cells, compared with controls. Treatment of patient RPE with AAV vectors significantly increased RCBTB1, NFE2L2 and RXRA expression and cilium lengths. Our study provides the first report examining the phenotype of RPE cells derived from a patient with RCBTB1-associated retinopathy. Furthermore, treatment of patient-derived RPE with AAV-RCBTB1 vectors corrected deficits in gene expression and RPE ultrastructure, supporting the use of gene replacement therapy for treating this inherited retinal disease.

The role of voltage-gated ion channels in visual function and disease in mammalian photoreceptors.

Light activation of the classical light-sensing retinal neurons, the photoreceptors, results in a graded change in membrane potential that ultimately leads to a reduction in neurotransmitter release to the post-synaptic retinal neurons. Photoreceptors show striking powers of adaptation, and for visual processing to function optimally, they must adjust their gain to remain responsive to different levels of ambient light intensity. The presence of a tightly controlled balance of inward and outward currents modulated by several different types of ion channels is what gives photoreceptors their remarkably dynamic operating range. Part of the resetting and modulation of this operating range is controlled by potassium and calcium voltage-gated channels, which are involved in setting the dark resting potential and synapse signal processing, respectively. Their essential contribution to visual processing is further confirmed in patients suffering from cone dystrophy with supernormal rod response (CDSRR) and congenital stationary night blindness type 2 (CSNB2), both conditions that lead to irreversible vision loss. This review will discuss these two types of voltage-gated ion channels present in photoreceptors, focussing on their structure and physiology, and their role in visual processing. It will also discuss the use and benefits of knockout mouse models to further study the function of these channels and what routes to potential treatments could be applied for CDSRR and CSNB2.

Leishmania eukaryotic elongation Factor-1 beta protein is immunogenic and induces parasitological protection in mice against Leishmania infantum infection.

Treatment for visceral leishmaniasis (VL) is hampered mainly by the toxicity and/or high cost of antileishmanial drugs. What is more, variability on sensitivity and/or specificity of diagnostic tests hinders effective disease management. In this context, prophylactic vaccination should be considered as a strategy to prevent disease. In the present study, immunogenicity of the Leishmania eukaryotic Elongation Factor-1 beta (EF1b) protein, classified as a Leishmania virulence factor, was evaluated in vitro and in vivo and tested, for the first time, as a vaccine candidate against Leishmania infantum infection. The antigen was administered as DNA vaccine or as recombinant protein (rEF1b) delivered in saponin. BALB/c mice immunization with a DNA plasmid and recombinant protein plus saponin induced development of specific Th1-type immunity, characterized by high levels of IFN-γ, IL-12, GM-CSF, both T cell subtypes and antileishmanial IgG2a isotype antibodies, before and after infection. This immunological response to the vaccines was corroborated further by parasitological analysis of the vaccinated and then challenged mice, which showed significant reductions in the parasite load in their liver, spleen, bone marrow and draining lymph nodes, when compared to the controls. Vaccination using rEF1b/saponin induced a more robust Th1 response and parasitological protection when compared to the DNA vaccine. Furthermore, in vitro analysis of lymphoproliferation, IFN-γ and IL-10 levels in human PBMC cultures showed as well development of a specific Th1-type response. In conclusion, data suggest that EF1b could be a promising vaccine candidate to protect against L. infantum infection.

Shared mechanisms between coronary heart disease and depression: findings from a large UK general population-based cohort.

While comorbidity between coronary heart disease (CHD) and depression is evident, it is unclear whether the two diseases have shared underlying mechanisms. We performed a range of analyses in 367,703 unrelated middle-aged participants of European ancestry from UK Biobank, a population-based cohort study, to assess whether comorbidity is primarily due to genetic or environmental factors, and to test whether cardiovascular risk factors and CHD are likely to be causally related to depression using Mendelian randomization. We showed family history of heart disease was associated with a 20% increase in depression risk (95% confidence interval [CI] 16-24%, p < 0.0001), but a genetic risk score that is strongly associated with CHD risk was not associated with depression. An increase of 1 standard deviation in the CHD genetic risk score was associated with 71% higher CHD risk, but 1% higher depression risk (95% CI 0-3%; p = 0.11). Mendelian randomization analyses suggested that triglycerides, interleukin-6 (IL-6), and C-reactive protein (CRP) are likely causal risk factors for depression. The odds ratio for depression per standard deviation increase in genetically-predicted triglycerides was 1.18 (95% CI 1.09-1.27; p = 2 × 10-5); per unit increase in genetically-predicted log-transformed IL-6 was 0.74 (95% CI 0.62-0.89; p = 0.0012); and per unit increase in genetically-predicted log-transformed CRP was 1.18 (95% CI 1.07-1.29; p = 0.0009). Our analyses suggest that comorbidity between depression and CHD arises largely from shared environmental factors. IL-6, CRP and triglycerides are likely to be causally linked with depression, so could be targets for treatment and prevention of depression.

Establishment of monoclonal antibodies to evaluate the cellular immunity in a hamster model of L infantum infection.

Syrian hamsters (Mesocricetus auratus) are largely used as a model for infectious diseases because it is very susceptible to several pathogens, including Leishmania spp. parasites. However, the research community faces limitations in its use due to the lack of immunological reagents and tools to study the immune system in this model. In this context, we proposed the validation of some important commercially anti-mouse mAbs (CD4, TNF-α, IFN-γ and IL-10) and how this could be useful to evaluate a specific cellular immune response in Leishmania-infected hamster using flow cytometry experiments. Our data demonstrated a cross-reactivity between these anti-mouse mAbs and hamster molecules that were herein studied. Beyond that, it was able to characterize the development of a specific cellular immune response through cytokine production in L infantum-infected hamsters when compared to uninfected ones. These data not only aid the usage of hamsters as experimental model to investigate various infectious diseases, but they contribute to the design of novel approaches to further investigate the immunological mechanisms associated to pathogen infections.

Molecular, Cellular and Functional Changes in the Retinas of Young Adult Mice Lacking the Voltage-Gated K+ Channel Subunits Kv8.2 and K2.1.

Cone Dystrophy with Supernormal Rod Response (CDSRR) is a rare autosomal recessive disorder leading to severe visual impairment in humans, but little is known about its unique pathophysiology. We have previously shown that CDSRR is caused by mutations in the KCNV2 (Potassium Voltage-Gated Channel Modifier Subfamily V Member 2) gene encoding the Kv8.2 subunit, a modulatory subunit of voltage-gated potassium (Kv) channels. In a recent study, we validated a novel mouse model of Kv8.2 deficiency at a late stage of the disease and showed that it replicates the human electroretinogram (ERG) phenotype. In this current study, we focused our investigation on young adult retinas to look for early markers of disease and evaluate their effect on retinal morphology, electrophysiology and immune response in both the Kv8.2 knockout (KO) mouse and in the Kv2.1 KO mouse, the obligate partner of Kv8.2 in functional retinal Kv channels. By evaluating the severity of retinal dystrophy in these KO models, we demonstrated that retinas of Kv KO mice have significantly higher apoptotic cells, a thinner outer nuclear cell layer and increased activated microglia cells in the subretinal space. Our results indicate that in the murine retina, the loss of Kv8.2 subunits contributes to early cellular and physiological changes leading to retinal dysfunction. These results could have potential implications in the early management of CDSRR despite its relatively nonprogressive nature in humans.

A Leishmania amastigote-specific hypothetical protein evaluated as recombinant protein plus Th1 adjuvant or DNA plasmid-based vaccine to protect against visceral leishmaniasis.

Most studies evaluating vaccine candidates against visceral leishmaniasis (VL) have used parasite promastigote-expressed antigens; however, Leishmania proteins expressed in the amastigote forms should be considered, since few hours after infection this stage comes into contact with the host immune system and is responsible for the development of the disease. In this context, in the present study, a Leishmania amastigote-specific hypothetical protein, called LiHyJ, was evaluated as a recombinant protein plus saponin as an adjuvant or DNA vaccine to protect against VL. The vaccine effect was evaluated by means of the evaluation of immunological and parasitological analyses performed in BALB/c mice against Leishmania infantum infection. Results showed that rLiHyJ/saponin and DNA LiHyJ induced significantly higher levels of anti-protein and anti-parasite IFN-γ, IL-12, GM-CSF, and IgG2a isotype antibodies, which were associated with a low presence of IL-4 and IL-10. DNA vaccination induced higher IFN-γ production, mainly by CD8+ T cells, while rLiHyJ/saponin stimulated the production of this cytokine, mainly by CD4+ T cells. The parasite load evaluated in distinct organs showed that both immunization schedules significantly reduced organic parasitism, when compared to the controls. Similar results were found in the immunological and parasitological assays when using the recombinant protein or DNA, although the vaccination with rLiHyJ plus saponin induced a slightly higher Th1 response and lower parasite load, when compared to the use of DNA plasmid. The protein also proved to be immunogenic when peripheral blood mononuclear cells of treated VL patients and healthy subjects were in vitro stimulated, since higher IFN-γ and lower IL-4 and IL-10 levels were found in the culture supernatants. In conclusion, LiHyJ should be considered in future studies as a vaccine candidate to protect against VL.