The coupling between healthspan and lifespan in Caenorhabditis depends on complex interactions between compound intervention and genetic background.

Aging is characterized by declining health that results in decreased cellular resilience and neuromuscular function. The relationship between lifespan and health, and the influence of genetic background on that relationship, has important implications in the development of pharmacological anti-aging interventions. Here we assessed swimming performance as well as survival under thermal and oxidative stress across a nematode genetic diversity test panel to evaluate health effects for three compounds previously studied in the Caenorhabditis Intervention Testing Program and thought to promote longevity in different ways - NP1 (nitrophenyl piperazine-containing compound 1), propyl gallate, and resveratrol. Overall, we find the relationships among median lifespan, oxidative stress resistance, thermotolerance, and mobility vigor to be complex. We show that oxidative stress resistance and thermotolerance vary with compound intervention, genetic background, and age. The effects of tested compounds on swimming locomotion, in contrast, are largely species-specific. In this study, thermotolerance, but not oxidative stress or swimming ability, correlates with lifespan. Notably, some compounds exert strong impact on some health measures without an equally strong impact on lifespan. Our results demonstrate the importance of assessing health and lifespan across genetic backgrounds in the effort to identify reproducible anti-aging interventions, with data underscoring how personalized treatments might be required to optimize health benefits.

Soluble pathogenic tau enters brain vascular endothelial cells and drives cellular senescence and brain microvascular dysfunction in a mouse model of tauopathy.

Vascular mechanisms of Alzheimer's disease (AD) may constitute a therapeutically addressable biological pathway underlying dementia. We previously demonstrated that soluble pathogenic forms of tau (tau oligomers) accumulate in brain microvasculature of AD and other tauopathies, including prominently in microvascular endothelial cells. Here we show that soluble pathogenic tau accumulates in brain microvascular endothelial cells of P301S(PS19) mice modeling tauopathy and drives AD-like brain microvascular deficits. Microvascular impairments in P301S(PS19) mice were partially negated by selective removal of pathogenic soluble tau aggregates from brain. We found that similar to trans-neuronal transmission of pathogenic forms of tau, soluble tau aggregates are internalized by brain microvascular endothelial cells in a heparin-sensitive manner and induce microtubule destabilization, block endothelial nitric oxide synthase (eNOS) activation, and potently induce endothelial cell senescence that was recapitulated in vivo in microvasculature of P301S(PS19) mice. Our studies suggest that soluble pathogenic tau aggregates mediate AD-like brain microvascular deficits in a mouse model of tauopathy, which may arise from endothelial cell senescence and eNOS dysfunction triggered by internalization of soluble tau aggregates.

Effect of Nrf2 loss on senescence and cognition of tau-based P301S mice.

Cellular senescence may contribute to chronic inflammation involved in the progression of age-related diseases such as Alzheimer's disease (AD), and its removal prevents cognitive impairment in a model of tauopathy. Nrf2, the major transcription factor for damage response pathways and regulators of inflammation, declines with age. Our previous work showed that silencing Nrf2 gives rise to premature senescence in cells and mice. Others have shown that Nrf2 ablation can exacerbate cognitive phenotypes of some AD models. In this study, we aimed to understand the relationship between Nrf2 elimination, senescence, and cognitive impairment in AD, by generating a mouse model expressing a mutant human tau transgene in an Nrf2 knockout (Nrf2KO) background. We assessed senescent cell burden and cognitive decline of P301S mice in the presence and absence of Nrf2. Lastly, we administered 4.5-month-long treatments with two senotherapeutic drugs to analyze their potential to prevent senescent cell burden and cognitive decline: the senolytic drugs dasatinib and quercetin (DQ) and the senomorphic drug rapamycin. Nrf2 loss accelerated the onset of hind-limb paralysis in P301S mice. At 8.5 months of age, P301S mice did not exhibit memory deficits, while P301S mice without Nrf2 were significantly impaired. However, markers of senescence were not elevated by Nrf2 ablation in any of tissues that we examined. Neither drug treatment improved cognitive performance, nor did it reduce expression of senescence markers in brains of P301S mice. Contrarily, rapamycin treatment at the doses used delayed spatial learning and led to a modest decrease in spatial memory. Taken together, our data suggests that the emergence of senescence may be causally associated with onset of cognitive decline in the P301S model, indicate that Nrf2 protects brain function in a model of AD through mechanisms that may include, but do not require the inhibition of senescence, and suggest possible limitations for DQ and rapamycin as therapies for AD.

[Prevalence of recurrent aphthous stomatitis in a family medical office, Manzanillo, Cuban. A cross-sectional study]. / Prevalencia de estomatitis aftosa recurrente en un consultorio médico de familia, Manzanillo, Cuba. Un estudio transversal.

Introduction: Recurrent Aphthous Stomatitis, also known as aphthous ulcers or simply aphthous, is considered the most common of oral mucosal lesions. Objective: To describe the prevalence of recurrent aphthous stomatitis. Methods: Descriptive, cross-sectional and prospective study. 847 patients who attended the Family Medical Office No. 28, San Francisco comunity, Manzanillo, from July 1, 2021 to June 30, 2022, Cuba, were evaluated. A calibrated and trained assistant investigator evaluated the following variables: Clinical classification of recurrent aphthous stomatitis (minor aphthosis, major aphthosis, or aphthosis herpetiformis), lesion pain intensity, lesion location, and risk factors (viral infection), bacterial infection, immunological alterations, psychosomatic alterations, oral trauma, gastrointestinal alterations, endocrine factors, allergic conditions, heredity, blood and nutritional deficiencies, smoking), age group, sex, race, and duration of the lesion. Results: Aphthous stomatitis occurred in 30.46%, with greater frequency in the age group 30 - 39 years (24.42%). Minor aphthosis was the most frequent with 91.09%. The duration of the lesion of 10 to 12 days predominated with 37.60%, the most frequent location corresponded to the edge and tip of the tongue with 32.94% and the most representative pain intensity was mild with a total of 63.18%. The highest frequency among the risk factors corresponded to psychosomatic alterations with 100%. Conclusions: Recurrent Aphthous Stomatitis had a prevalence greater than 30% with a predominance of the female sex and young adults. Minor Aphtosis and a stay time of more than 10 days were the most frequent. The most common location is the tongue and bottom of the vestibular sulcus with the possible existence of a relationship between the mobile parts of the mouth. Stress, the main risk factor, exacerbated by Covid-19.

Mitochondrial Dysfunction and the Glycolytic Switch Induced by Caveolin-1 Phosphorylation Promote Cancer Cell Migration, Invasion, and Metastasis.

Cancer cells often display impaired mitochondrial function, reduced oxidative phosphorylation, and augmented aerobic glycolysis (Warburg effect) to fulfill their bioenergetic and biosynthetic needs. Caveolin-1 (CAV1) is a scaffolding protein that promotes cancer cell migration, invasion, and metastasis in a manner dependent on CAV1 phosphorylation on tyrosine-14 (pY14). Here, we show that CAV1 expression increased glycolysis rates, while mitochondrial respiration was reduced by inhibition of the mitochondrial complex IV. These effects correlated with increased reactive oxygen species (ROS) levels that favored CAV1-induced migration and invasion. Interestingly, pY14-CAV1 promoted the metabolic switch associated with increased migration/invasion and augmented ROS-inhibited PTP1B, a phosphatase that controls pY14 levels. Finally, the glycolysis inhibitor 2-deoxy-D-glucose reduced CAV1-enhanced migration in vitro and metastasis in vivo of murine melanoma cells. In conclusion, CAV1 promotes the Warburg effect and ROS production, which inhibits PTP1B to augment CAV1 phosphorylation on tyrosine-14, thereby increasing the metastatic potential of cancer cells.

Brain cellular senescence in mouse models of Alzheimer's disease.

The accumulation of senescent cells contributes to aging pathologies, including neurodegenerative diseases, and its selective removal improves physiological and cognitive function in wild-type mice as well as in Alzheimer's disease (AD) models. AD models recapitulate some, but not all components of disease and do so at different rates. Whether brain cellular senescence is recapitulated in some or all AD models and whether the emergence of cellular senescence in AD mouse models occurs before or after the expected onset of AD-like cognitive deficits in these models are not yet known. The goal of this study was to identify mouse models of AD and AD-related dementias that develop measurable markers of cellular senescence in brain and thus may be useful to study the role of cellular senescence in these conditions. We measured the levels of cellular senescence markers in the brains of P301S(PS19), P301L, hTau, and 3xTg-AD mice that model amyloidopathy and/or tauopathy in AD and related dementias and in wild-type, age-matched control mice for each strain. Expression of cellular senescence markers in brains of transgenic P301L and 3xTg-AD mice was largely indistinguishable from that in WT control age-matched mice. In contrast, markers of cellular senescence were differentially increased in brains of transgenic hTau and P301S(PS19) mice as compared to WT control mice before the onset of AD-like cognitive deficits. Taken together, our data suggest that P301S(PS19) and hTau mice may be useful models for the study of brain cellular senescence in tauopathies including, but not limited to, AD.

Genetic diversity estimates for the Caenorhabditis Intervention Testing Program screening panel.

The Caenorhabditis Intervention Testing Program (CITP) was founded on the principle that compounds with positive effects across a genetically diverse test-set should have an increased probability of engaging conserved biochemical pathways with mammalian translational potential. To fulfill its mandate, the CITP uses a genetic diversity panel of Caenorhabditis strains for assaying longevity effects of candidate compounds. The panel comprises 22 strains from three different species, collected globally, to achieve inter-population genetic diversity. The three represented species, C. elegans, C. briggsae, and C. tropicalis, are all sequential hermaphrodites, which simplifies experimental procedures while maximizing intra-population homogeneity. Here, we present estimates of the genetic diversity encapsulated by the constituent strains in the panel based on their most recently published and publicly available whole-genome sequences, as well as two newly generated genomic data sets. We observed average genome-wide nucleotide diversity (π) within the C. elegans (1.2e-3), C. briggsae (7.5e-3), and C. tropicalis strains (2.6e-3) greater than estimates for human populations, and comparable to that found in mouse populations. Our analysis supports the assumption that the CITP screening panel encompasses broad genetic diversity, suggesting that lifespan-extending chemicals with efficacy across the panel should be enriched for interventions that function on conserved processes that are shared across genetic backgrounds. While the diversity panel was established by the CITP for studying longevity interventions, the panel may prove useful for the broader research community when seeking broadly efficacious interventions for any phenotype with potential genetic background effects.

Transport and Secretion of the Wnt3 Ligand by Motor Neuron-like Cells and Developing Motor Neurons.

The vertebrate neuromuscular junction (NMJ) is formed by a presynaptic motor nerve terminal and a postsynaptic muscle specialization. Cumulative evidence reveals that Wnt ligands secreted by the nerve terminal control crucial steps of NMJ synaptogenesis. For instance, the Wnt3 ligand is expressed by motor neurons at the time of NMJ formation and induces postsynaptic differentiation in recently formed muscle fibers. However, the behavior of presynaptic-derived Wnt ligands at the vertebrate NMJ has not been deeply analyzed. Here, we conducted overexpression experiments to study the expression, distribution, secretion, and function of Wnt3 by transfection of the motor neuron-like NSC-34 cell line and by in ovo electroporation of chick motor neurons. Our findings reveal that Wnt3 is transported along motor axons in vivo following a vesicular-like pattern and reaches the NMJ area. In vitro, we found that endogenous Wnt3 expression increases as the differentiation of NSC-34 cells proceeds. Although NSC-34 cells overexpressing Wnt3 do not modify their morphological differentiation towards a neuronal phenotype, they effectively induce acetylcholine receptor clustering on co-cultured myotubes. These findings support the notion that presynaptic Wnt3 is transported and secreted by motor neurons to induce postsynaptic differentiation in nascent NMJs.

Rapamycin impairs bone accrual in young adult mice independent of Nrf2.

Advanced age is the strongest risk factor for osteoporosis. The immunomodulator drug rapamycin extends lifespan in numerous experimental model organisms and is being investigated as a potential therapeutic to slow human aging, but little is known about the effects of rapamycin on bone. We evaluated the impact of rapamycin treatment on bone mass, architecture, and indices of bone turnover in healthy adult (16-20 weeks old at treatment initiation) female wild-type (ICR) and Nrf2-/- mice, a mouse model of oxidative damage and aging-related disease vulnerability. Rapamycin (4 mg/kg bodyweight) was administered by intraperitoneal injection every other day for 12 weeks. Mice treated with rapamycin exhibited lower femur bone mineral content, bone mineral density, and bone volume compared to vehicle-treated mice. In midshaft femur diaphysis (cortical bone), rapamycin-treated mice had lower cortical volume and thickness, and in the distal femur metaphysis (cancellous bone), rapamycin-treated mice had higher trabecular spacing and lower connectivity density. Mice treated with rapamycin exhibited lower bone volume, bone volume fraction, and trabecular thickness in the 5th lumbar vertebra. Rapamycin-treated mice had lower levels of bone formation in the distal femur metaphysis compared to vehicle-treated mice which occurred co-incidentally with increased serum CTX-1, a marker of global bone resorption. Rapamycin had no impact on tibia inflammatory cytokine gene expression, and we found no independent effects of Nrf2 knockout on bone, nor did we find any interactions between genotype and treatment. These data show that rapamycin may have a negative impact on the skeleton of adult mice that should not be overlooked in the clinical context of its usage as a therapy to retard aging and reduce the incidence of age-related pathologies.

Protein disulfide isomerase ERp57 protects early muscle denervation in experimental ALS.

Amyotrophic lateral sclerosis (ALS) is a progressive fatal neurodegenerative disease that affects motoneurons. Mutations in superoxide dismutase 1 (SOD1) have been described as a causative genetic factor for ALS. Mice overexpressing ALS-linked mutant SOD1 develop ALS symptoms accompanied by histopathological alterations and protein aggregation. The protein disulfide isomerase family member ERp57 is one of the main up-regulated proteins in tissue of ALS patients and mutant SOD1 mice, whereas point mutations in ERp57 were described as possible risk factors to develop the disease. ERp57 catalyzes disulfide bond formation and isomerization in the endoplasmic reticulum (ER), constituting a central component of protein quality control mechanisms. However, the actual contribution of ERp57 to ALS pathogenesis remained to be defined. Here, we studied the consequences of overexpressing ERp57 in experimental ALS using mutant SOD1 mice. Double transgenic SOD1G93A/ERp57WT animals presented delayed deterioration of electrophysiological activity and maintained muscle innervation compared to single transgenic SOD1G93A littermates at early-symptomatic stage, along with improved motor performance without affecting survival. The overexpression of ERp57 reduced mutant SOD1 aggregation, but only at disease end-stage, dissociating its role as an anti-aggregation factor from the protection of neuromuscular junctions. Instead, proteomic analysis revealed that the neuroprotective effects of ERp57 overexpression correlated with increased levels of synaptic and actin cytoskeleton proteins in the spinal cord. Taken together, our results suggest that ERp57 operates as a disease modifier at early stages by maintaining motoneuron connectivity.

The Mouse Levator Auris Longus Muscle: An Amenable Model System to Study the Role of Postsynaptic Proteins to the Maintenance and Regeneration of the Neuromuscular Synapse.

The neuromuscular junction (NMJ) is the peripheral synapse that controls the coordinated movement of many organisms. The NMJ is also an archetypical model to study synaptic morphology and function. As the NMJ is the primary target of neuromuscular diseases and traumatic injuries, the establishment of suitable models to study the contribution of specific postsynaptic muscle-derived proteins on NMJ maintenance and regeneration is a permanent need. Considering the unique experimental advantages of the levator auris longus (LAL) muscle, here we present a method allowing for efficient electroporation-mediated gene transfer and subsequent detailed studies of the morphology and function of the NMJ and muscle fibers. Also, we have standardized efficient facial nerve injury protocols to analyze LAL muscle NMJ degeneration and regeneration. Our results show that the expression of a control fluorescent protein does not alter either the muscle structural organization, the apposition of the pre- and post-synaptic domains, or the functional neurotransmission parameters of the LAL muscle NMJs; in turn, the overexpression of MuSK, a major regulator of postsynaptic assembly, induces the formation of ectopic acetylcholine receptor clusters. Our NMJ denervation experiments showed complete reinnervation of LAL muscle NMJs four weeks after facial nerve injury. Together, these experimental strategies in the LAL muscle constitute effective methods to combine protein expression with accurate analyses at the levels of structure, function, and regeneration of the NMJ.

Association between depressive symptoms in mothers and metabolic control in adolescents with type 1 diabetes. / Asociación entre síntomas depresivos de las madres y control metabólico en adolescentes con Diabetes Mellitus tipo 1.

INTRODUCTION: Poor metabolic control in patients with Type 1 Diabetes Mellitus (T1DM) is associated with short- and long-term complications. Adolescents with T1DM present poorer metabolic control than pa tients of other age groups. Few studies have shown an association between mothers with depressive symptoms and the metabolic control of their adolescent children. OBJECTIVE: To evaluate the associa tion between maternal depressive symptoms and metabolic control of their adolescents with T1DM. SUBJECTS AND METHOD: Cross-sectional observational study carried out with adolescents aged between 10 and 18 years, with T1DM diagnosis of at least 1 year ago and their mothers. The Beck Depression Inventory-II and the SALUFAM questionnaire were applied, and sociodemographic data were co llected. Glycosylated hemoglobin from capillary blood was used as a marker of metabolic control. RESULTS: 86 couples (mother-adolescent children) were studied. The average age of the adolescents was 14.04 years and the average evolution time of T1DM was 5.95 years. 27.325.6% of mothers had depressive symptoms, which was associated with worse metabolic control of their children (HbA1c of 7.66% and 8.91%, p-value <0.001). 17.9% of adolescents had depressive symptoms, which was not associated with maternal depressive symptoms or worse metabolic control. Maternal depressive symptoms were also associated with lower maternal and paternal educational levels, high number of children in the family, presence of other siblings with chronic illnesses, and high health vulnera bility (SALUFAM). CONCLUSIONS: The mother's depressive symptoms can be associated with worst metabolic control in T1MD adolescents. It is fundamental a multidisciplinary family approach to get better metabolic controls in T1DM adolescents.

Aggresome-Like Formation Promotes Resistance to Proteotoxicity in Cells from Long-Lived Species.

The capacity of cells to maintain proteostasis declines with age, causing rapid accumulation of damaged proteins and protein aggregates, which plays an important role in age-related disease etiology. While our group and others have identified that proteostasis is enhanced in long-lived species, there are no data on whether this leads to better resistance to proteotoxicity. We compared the sensitivity of cells from long- (naked mole rat [NMR]) and short- (Mouse) lived species to proteotoxicity, by measuring the survival of fibroblasts under polyglutamine (polyQ) toxicity, a well-established model of protein aggregation. Additionally, to evaluate the contribution of proteostatic mechanisms to proteotoxicity resistance, we down-regulated a key protein of each mechanism (autophagy-ATG5; ubiquitin-proteasome-PSMD14; and chaperones-HSP27) in NMR fibroblasts. Furthermore, we analyzed the formation and subcellular localization of inclusions in long- and short-lived species. Here, we show that fibroblasts from long-lived species are more resistant to proteotoxicity than their short-lived counterparts. Surprisingly, this does not occur because the NMR cells have less polyQ82 protein aggregates, but rather they have an enhanced capacity to handle misfolded proteins and form protective perinuclear and aggresome-like inclusions. All three proteostatic mechanisms contribute to this resistance to polyQ toxicity but autophagy has the greatest effect. Overall, our data suggest that the resistance to proteotoxicity observed in long-lived species is not due to a lower level of protein aggregates but rather to enhanced handling of the protein aggregates through the formation of aggresome-like inclusions, a well-recognized protective mechanism against proteotoxicty.

Asociación entre síntomas depresivos de las madres y control metabólico en adolescentes con Diabetes Mellitus tipo 1 / Association between depressive symptoms in mothers and metabolic control in adolescents with type 1 diabetes

Resumen: Introducción: Un mal control metabólico en pacientes con Diabetes Mellitus tipo 1 (DM1) se asocia a complica ciones a corto y largo plazo. Los adolescentes con Diabetes tipo 1 presentan peor control metabólico comparado con pacientes de otros grupos etarios. Escasos estudios han demostrado una asociación entre síntomas depresivos de las madres con el control metabólico de sus hijos adolescente. Objetivo: Evaluar la asociación entre síntomas depresivos maternos y control metabólico de adolescentes con DM1. Sujetos y Método: Estudio observacional transversal realizado en adolescentes, edades 10 a 18 años, con diagnóstico de DM1 de más de un año de evolución y sus madres. Se aplicó test de Beck II, cuestionario de depresión infantil, cuestionario SALUFAM y cuestionario de datos sociodemográficos. Se realizó hemoglobina glicosilada capilar, como marcador de control metabólico. Resultados: Se estudiaron 86 parejas (madre-hijo adolescente), adolescentes de edad media 14.04 años y 5.95 años de evolución de DM1. El 25.6% (n 22) de las madres presentó síntomas depresivos, asociándose a peor control metabólico en sus hijos (HbA1c: 7.66% y 8.91%, p < 0.001). El 17.9% de adolescentes presentó síntomas depresivos, no asociándose a síntomas depresivos maternos ni a peor control metabólico. Los síntomas depresivos maternos se asociaron a menor nivel educacional materno y pater no, mayor número de hijos en la familia, presencia de otros hermanos con enfermedades crónicas y a mayor vulnerabilidad en salud (SALUFAM). Conclusiones: La presencia de síntomas depresivos maternos se asocia a peor control metabólico en el adolescente con DM1, siendo fundamental un enfoque multidisciplinario familiar para obtener mejores resultados metabólicos en los adolescentes.

Abstract: Introduction: Poor metabolic control in patients with Type 1 Diabetes Mellitus (T1DM) is associated with short- and long-term complications. Adolescents with T1DM present poorer metabolic control than patients of other age groups. Few studies have shown an association between mothers with depressive symptoms and the metabolic control of their adolescent children. Objective: To evaluate the associa tion between maternal depressive symptoms and metabolic control of their adolescents with T1DM. Subjects and Method: Cross-sectional observational study carried out with adolescents aged between 10 and 18 years, with T1DM diagnosis of at least 1 year ago and their mothers. The Beck Depression Inventory-II and the SALUFAM questionnaire were applied, and sociodemographic data were co llected. Glycosylated hemoglobin from capillary blood was used as a marker of metabolic control. Results: 86 couples (mother-adolescent children) were studied. The average age of the adolescents was 14.04 years and the average evolution time of T1DM was 5.95 years. 27.325.6% of mothers had depressive symptoms, which was associated with worse metabolic control of their children (HbA1c of 7.66% and 8.91%, p-value <0.001). 17.9% of adolescents had depressive symptoms, which was not associated with maternal depressive symptoms or worse metabolic control. Maternal depressive symptoms were also associated with lower maternal and paternal educational levels, high number of children in the family, presence of other siblings with chronic illnesses, and high health vulnera bility (SALUFAM). Conclusions: The mother's depressive symptoms can be associated with worst metabolic control in T1MD adolescents. It is fundamental a multidisciplinary family approach to get better metabolic controls in T1DM adolescents.

The non-receptor tyrosine phosphatase type 14 blocks caveolin-1-enhanced cancer cell metastasis.

Caveolin-1 (CAV1) enhanced migration, invasion, and metastasis of cancer cells is inhibited by co-expression of the glycoprotein E-cadherin. Although the two proteins form a multiprotein complex that includes ß-catenin, it remained unclear how this would contribute to blocking the metastasis promoting function of CAV1. Here, we characterized by mass spectrometry the protein composition of CAV1 immunoprecipitates from B16F10 murine melanoma cells expressing or not E-cadherin. The novel protein tyrosine phosphatase PTPN14 was identified by mass spectrometry analysis exclusively in co-immunoprecipitates of CAV1 with E-cadherin. Interestingly, PTPN14 is implicated in controlling metastasis, but only few known PTPN14 substrates exist. We corroborated by western blotting experiments that PTPN14 and CAV1 co-inmunoprecipitated in the presence of E-cadherin in B16F10 melanoma and other cancer cells. Moreover, the CAV1(Y14F) mutant protein was shown to co-immunoprecipitate with PTPN14 even in the absence of E-cadherin, and overexpression of PTPN14 reduced CAV1 phosphorylation on tyrosine-14, as well as suppressed CAV1-enhanced cell migration, invasion and Rac-1 activation in B16F10, metastatic colon [HT29(US)] and breast cancer (MDA-MB-231) cell lines. Finally, PTPN14 overexpression in B16F10 cells reduced the ability of CAV1 to induce metastasis in vivo. In summary, we identify here CAV1 as a novel substrate for PTPN14 and show that overexpression of this phosphatase suffices to reduce CAV1-induced metastasis.

The p75NTR neurotrophin receptor is required to organize the mature neuromuscular synapse by regulating synaptic vesicle availability.

The coordinated movement of organisms relies on efficient nerve-muscle communication at the neuromuscular junction. After peripheral nerve injury or neurodegeneration, motor neurons and Schwann cells increase the expression of the p75NTR pan-neurotrophin receptor. Even though p75NTR targeting has emerged as a promising therapeutic strategy to delay peripheral neuronal damage progression, the effects of long-term p75NTR inhibition at the mature neuromuscular junction have not been elucidated. We performed quantitative neuroanathomical analyses of the neuromuscular junction in p75NTR null mice by laser confocal and electron microscopy, which were complemented with electromyography, locomotor tests, and pharmacological intervention studies. Mature neuromuscular synapses of p75NTR null mice show impaired postsynaptic organization and ultrastructural complexity, which correlate with altered synaptic function at the levels of nerve activity-induced muscle responses, muscle fiber structure, force production, and locomotor performance. Our results on primary myotubes and denervated muscles indicate that muscle-derived p75NTR does not play a major role on postsynaptic organization. In turn, motor axon terminals of p75NTR null mice display a strong reduction in the number of synaptic vesicles and active zones. According to the observed pre and postsynaptic defects, pharmacological acetylcholinesterase inhibition rescued nerve-dependent muscle response and force production in p75NTR null mice. Our findings revealing that p75NTR is required to organize mature neuromuscular junctions contribute to a comprehensive view of the possible effects caused by therapeutic attempts to target p75NTR.

Efficient gene transfer into primary muscle cells to analyze nerve-independent postsynaptic organization in vitro.

Acetylcholine receptor (AChR) clustering on the surface of muscle cells is a hallmark of postsynaptic differentiation at the vertebrate neuromuscular junction (NMJ). Even though the assembly of complex postsynaptic apparatuses is known to rely on both, pre- and postsynaptic signals, the identity of muscle-derived proteins modulating postsynaptic assembly and maintenance is still to be fully elucidated. Efficient gene transfer into muscle cells represents a powerful tool to analyze the contribution of muscle proteins on postsynaptic assembly and maintenance. Here, we describe a protocol that combines efficient electroporation of primary muscle satellite cells with the formation of aneural complex postsynaptic structures on the surface of myotubes. In vitro formed postsynaptic structures share various similarities with in vivo postsynaptic NMJ domains. While primary myotubes express increasing amounts of the ε AChR subunit, associated with NMJ maturation, surface AChR aggregates lack this AChR subunit. Our results also validate the functional expression of a luciferase reporter gene, as well as the response of complex postsynaptic structures to pharmacological treatment. Together, these methods in primary muscle cells are a valuable tool to perform a detailed and accurate analysis of the potential role of muscle-derived proteins on the maintenance of complex postsynaptic structures and to identify nerve-derived signals regulating functional NMJ maturation.

Remote induction of cellular immune response in mice by anti-meningococcal nanocochleates - nanoproteoliposomes.

New adjuvant formulations, based on proteoliposomes <40 nm and cochleates <100 nm, without Al(OH)3 adjuvant, were evaluated regarding their ability to generate Th1 immune response through a Delayed -Type Hypersensitivity Test, at the mouse model, by using a Neisseria meningitidis B protein complex as antigen. The formulations were administered by intramuscular (IM) (2 inoculations - at baseline and after 14 days) and intranasal (IN) (3 inoculations at 7 days) immunization pathways. All IM immunized groups were able to induce similar response to these formulations as well as to VA-MENGOC-BC® vaccine - containing Al(OH)3 adjuvant (used as positive control of the trial). In all groups, the induced inflammation (IP) rate was statistically higher than in the negative control group (CN) (p < 0.05). Immunogenicity, measured by HSR and CD4+ lymphocyte increase was equivalent to the control vaccine and most important, granuloma reactogenicity at the site of injection was eliminated, fact demonstrated by histological study. All groups of animals immunized by IN route showed HSR reactions and statistically significant differences with respect to the CN group. However, IP values were lower, with statistical differences (p < 0.05) for the same adjuvant formulation IM administered, except the AIF2-nCh formulation that generated statistically similar induction (p > 0.05) by both immunization pathways, suggesting it to be the best candidate for the next IN trial. Proteoliposome and cochleate formulations tested were able to mount potent Th-1 immune response, equivalent to the original vaccine formulation, with the advantage of less reactogenicity in the site of the injection, caused by the toxicity of Al(OH)3 adjuvant gel.

Artritis reumatoide y embarazo, a propósito de un caso / Rheumatoid arthritis and pregnancy, about a case

Introducción: La artritis reumatoide es una enfermedad inflamatoria sistémica y crónica que, aunque suele tener su pico de incidencia en edades superiores, también puede presentar en edades más tempranas de la vida. La gestación es estas pacientes es considerada una situación de elevado riesgo debido a la misma actividad de la enfermedad y al posible efecto teratogénico que pueden devenirse del uso de muchos de los fármacos que generalmente se utilizan en estos casos. Sin embargo, una correcta planificación, un adecuado seguimiento ginecobstétrico y reumatológico y la valoración sistemática de la actividad de la enfermedad, constituyen los elementos básicos de la atención médica durante este periodo. Objetivo: dar a conocer los elementos fundamentales del seguimiento de la gestación en pacientes con artritis reumatoide. Caso clínico: se presenta el caso de una paciente de 23 años de edad con diagnóstico de artritis reumatoide de 5 años de evolución que concibe una gestación que con todos los cuidados médicos se logra llegar a un feliz término. Conclusiones: al ser la artritis reumatoide una enfermedad de compleja evolución las pacientes jóvenes tienen cierto temor a la gestación, sin embargo, durante el embarazo se produce cierta mejoría clínica de la artritis. Es imprescindible garantizar la menor actividad posible para que no afecte el pronóstico y la salud materna y fetal(AU)

Introduction: Rheumatoid arthritis is a systemic and chronic inflammatory disease that, although it usually has its peak of incidence in older ages, can also present at younger ages of life. The pregnancy is these patients is considered a situation of high risk due to the same activity of the disease and the possible teratogenic effect that can be derived from the use of many of the drugs that are generally used in these cases. However, proper planning, adequate gynecobysteometric and rheumatological follow-up, and systematic assessment of disease activity are the basic elements of medical care during this period. Objective: to present the fundamental elements of the pregnancy follow-up in patients with rheumatoid arthritis. Clinical case: We present the case of a 23-year-old patient with a diagnosis of rheumatoid arthritis of 5 years of evolution who conceives a pregnancy that with all medical care is achieved a happy term. Conclusions: as rheumatoid arthritis is a disease of complex evolution young patients have some fear of pregnancy, however, during pregnancy there is some clinical improvement of arthritis. It is essential to guarantee as little activity as possible so that it does not affect prognosis and maternal and fetal health(AU)