Nutrient supply impacts osteocytic specification by regulating a nuclear transcription program

[spa] El hueso es un órgano con múltiples funciones. No sólo actúa como elemento de soporte, protección y locomoción, sino que también resulta indispensable en el mantenimiento del equilibrio mineral y ácido/base, conforma un nicho adecuado para el desarrollo de la hematopoyesis, y mantiene la homeostasis energética del organismo. En estos procesos, los osteocitos tienen un papel especialmente relevante, ya que actúan transduciendo estímulos mecánicos en señales bioquímicas. Los osteocitos constituyen el principal componente celular óseo. Derivan de osteoblastos, los cuales a su vez proceden de células madre mensenquimales (MSC). Los osteoblastos pueden seguir tres destinos alternativos: entrar en apoptosis, originar células de revestimiento óseo o progresar en la diferenciación hacia osteocitos. Actualmente, los estímulos y vías de señalización que regulan cada uno de estos procesos son desconocidos. Por ello, y teniendo en cuenta la importancia de los osteocitos en la homeostasis del organismo, consideramos necesario profundizar en su investigación. Durante el proceso de diferenciación ósea, los osteoblastos quedan embebidos en una matriz mineralizada que limita su disponibilidad de nutrientes, estando expuestos a un ambiente hipoglucémico al cual deben adaptarse. En este contexto Wei et al. demostraron que la glucosa juega un papel importante en la regulación de la diferenciación osteoblástica. Por otro lado, se ha observado que, en ambientes hiperglucémicos, típicos de pacientes diabéticos, se produce una reducción del número y función osteoblástica, así como una disminución de la densidad mineral ósea y alteración de la microarquitectura ósea. Teniendo en cuenta todo lo expuesto, estudiamos la capacidad de diferenciación de las IDG-SW3 en condiciones de hipoglucemia (1mM glucosa), normoglucemia (5mM glucosa) o hiperglucemia (25mM glucosa). Las condiciones de hipoglucemia promueven la diferenciación osteocitica, mientras que altas concentraciones de glucosa dificultan este proceso. A nivel metabólico, las condiciones de baja glucosa aumentan la cantidad de mitocondrias y su agrupación en forma de redes. Por otro lado, los ambientes hipoglucémicos, promueven los eventos de fisión mitocondrial. En este contexto PGC1α podría desempeñar un papel crucial como nexo entre el estrés metabólico y la reprogramación génica de los osteoblastos. PGC1α es un coactivador transcripcional que responde a diferentes tipos de estrés. Aunque sus dianas son múltiples, afectan principalmente a la expresión de genes implicados en el metabolismo, así como la biogénesis y función mitocondrial. PGC1 se activa a través de fosforilación y acetilación mediadas por AMPK y SIRT1. La activación de PGC1α, podría iniciar una reprogramación metabólica y génica que culminaría en una inducción de la diferenciación osteocítica

Detecciónes de la expresión de citoquinas mediante RT-PCR en tiempo real en ganado ovino

Las citoquinas son moléculas proteicas secretadas por diferentes células, fundamentalmente del sistema inmunitario, como respuesta a una estimulación inmunológica. Existen diferentes técnicas para estudiar la producción y acción de éstas en los individuos. Este estudio consiste en la puesta a punto de una técnica de Retrotranscripción- Reacción en cadena de la polimerasa (RT-PCR) en tiempo real para la detección de la expresión del ARNm que codifica seis citoquinas (TNF-α, IFNγ, IL-4, IL2, IL-10, IL-12). Los resultados preliminares se obtuvieron tras la aplicación de la técnica a linfocitos estimulados in vitro con ConA (Concanavalina A) y LPS (Lipopolisacárido de E.coli) demostrando la detección de ARNm para IL-4, IL-2 e IFNγ y TNF-α, IL-12 e IL-10, respectivamente; posteriormente se realizó el estudio en ovejas inmunizadas frente a Chlamydophyla abortus, permitiendo la detección de la expresión de ARNm de las seis citoquinas. Estos resultados demuestran que es una técnica rápida, sensible y fiable para la detección de citoquinas.Cytokines are protein molecules that cells from the immune system secrete in response to immune stimulation. There are different techniques to study their production and their action on individuals. This study consists of the development of a real time RT-PCR method for the detection of the expression of mRNA coding for six cytokines (TNF-α, IFNγ, IL-4, IL2, IL-10, IL-12). The preliminary results were obtained from the study of lymphocites stimulated with Con A and LPS, showing the detection of ARNm, IL-4, IL-2, IFNγ and TNF-α, IL-12, IL-10, respectively. Its subsequent application in sheep that were vaccinated against Chlamydophila abortus, allowed the detection of mRNA expression for the six cytokines. These results show that it is a swift, sensitive and reliable technique to detect mRNA of cytokines

Characterization of the Immune Response Induced by a Commercially Available Inactivated Bluetongue Virus Serotype 1 Vaccine in Sheep

The protective immune response generated by a commercial monovalent inactivated vaccine against bluetongue virus serotype 1 (BTV1) was studied. Five sheep were vaccinated, boost-vaccinated, and then challenged against BTV1 ALG/2006. RT-PCR did not detect viremia at any time during the experiment. Except a temperature increase observed after the initial and boost vaccinations, no clinical signs or lesions were observed. A specific and protective antibody response checked by ELISA was induced after vaccination and boost vaccination. This specific antibody response was associated with a significant increase in B lymphocytes confirmed by flow cytometry, while significant increases were not observed in T lymphocyte subpopulations (CD4+, CD8+, and WC1+), CD25+ regulatory cells, or CD14+ monocytes. After challenge with BTV1, the antibody response was much higher than during the boost vaccination period, and it was associated with a significant increase in B lymphocytes, CD14+ monocytes, CD25+ regulatory cells, and CD8+ cytotoxic T lymphocytes

Valoración de la producción de anticuerpos en un ensayo de vacunas VLP frente a los serotipos 1 y 4 de la lengua azul

El objetivo de este trabajo ha sido valorar mediante una prueba ELISA de competición los anticuerpos frente a VP7 generados por las vacunas VLP frente a los serotipos 1 y 1+4 de la lengua azul, así como tras el desafío de los animales, para poder conocer la respuesta humoral generada por estas vacunas. Los tres grupos de animales vacunados presentaron resultados positivos a los 35 días de la primera vacunación, mientras que en los animales no vacunados sólo se evidenció la presencia de anticuerpos a partir del día 10 tras el desafío. La presencia de anticuerpos en los animales vacunados indica la capacidad de las vacunas VLP para estimular la respuesta humoral.The main purpose of this study was to evaluate by a competitive ELISA test the VP7 antibodies in response to VLPs vaccines for bluetongue serotypes 1 & 1+4, and after the virus challenge, to assess the humoral immune response produced by these VLPs. The three vaccinated groups showed positive results 35 days after the vaccination. However, in non vaccinated animals antibodies were not detected before day 10 post virus challenge. The presence of antibodies in vaccinated animals implies that VLP Vaccines are able to stimulate a humoral response

Seguimiento clínico del ensayo de una vacuna VLP para los serotipos 1 y 1+4 de la lengua azul en ganado ovino

La Lengua azul es una enfermedad vírica sometida a un control sanitario compuesto por varias medidas de prevención, entre ellas la vacunación de las especies sensibles. En el desarrollo de vacunas frente a esta enfermedad, una nueva tendencia es la producción de vacunas polivalentes mediante la técnica de VLP (virus like particles). Este trabajo ha tenido como objetivo valorar mediante seguimiento clínico 2 vacunas VLP, frente al serotipo1 y frente a los serotipos 1+4. Los resultados confirman la falta de fiebre, sintomatología y lesiones anatomopatológicas en los animales vacunados frente a los controles, lo que indica que estas nuevas vacunas protegen frente a la aparición de sintomatología clínica.Bluetongue Virus disease is an infectous disease submitted to a sanitary control composed by several measures of prevention, and one of these measures is the vaccination of the sensible species. In the development of vaccines opposite to this disease, a new trend is the production of polyvalent vaccines by VLP's technology (virus like particles). This work has had as aim to value by clinical survey, 2 VLP vaccines, for serotypes 1 and 1+4. The results confirm the lack of fever, clinical signs and pathologic injuries in vaccinated animals opposite to control animals, which indicates that these new vaccines protect for the appearance of clinical signs

Colorectal Carcinoma: A General Overview and Future Perspectives in Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer and the fourth most common cause of cancer-related death. Most cases of CRC are detected in Western countries, with its incidence increasing year by year. The probability of suffering from colorectal cancer is about 4%–5% and the risk for developing CRC is associated with personal features or habits such as age, chronic disease history and lifestyle. In this context, the gut microbiota has a relevant role, and dysbiosis situations can induce colonic carcinogenesis through a chronic inflammation mechanism. Some of the bacteria responsible for this multiphase process include Fusobacterium spp, Bacteroides fragilis and enteropathogenic Escherichia coli. CRC is caused by mutations that target oncogenes, tumour suppressor genes and genes related to DNA repair mechanisms. Depending on the origin of the mutation, colorectal carcinomas can be classified as sporadic (70%); inherited (5%) and familial (25%). The pathogenic mechanisms leading to this situation can be included in three types, namely chromosomal instability (CIN), microsatellite instability (MSI) and CpG island methylator phenotype (CIMP). Within these types of CRC, common mutations, chromosomal changes and translocations have been reported to affect important pathways (WNT, MAPK/PI3K, TGF-ß, TP53), and mutations; in particular, genes such as c-MYC, KRAS, BRAF, PIK3CA, PTEN, SMAD2 and SMAD4 can be used as predictive markers for patient outcome. In addition to gene mutations, alterations in ncRNAs, such as lncRNA or miRNA, can also contribute to different steps of the carcinogenesis process and have a predictive value when used as biomarkers. In consequence, different panels of genes and mRNA are being developed to improve prognosis and treatment selection. The choice of first-line treatment in CRC follows a multimodal approach based on tumour-related characteristics and usually comprises surgical resection followed by chemotherapy combined with monoclonal antibodies or proteins against vascular endothelial growth factor (VEGF) and epidermal growth receptor (EGFR). Besides traditional chemotherapy, alternative therapies (such as agarose tumour macrobeads, anti-inflammatory drugs, probiotics, and gold-based drugs) are currently being studied to increase treatment effectiveness and reduce side effects

Kerker Conditions Upon Lossless, Absorption, and Optical Gain Regimes

The directionality and polarization of light show peculiar properties when the scattering by a dielectric sphere can be described exclusively by electric and magnetic dipolar modes. Particularly, when these modes oscillate in-phase with equal amplitude, at the so-called first Kerker condition, the zero optical backscattering condition emerges for non-dissipating spheres. However, the role of absorption and optical gain in the first Kerker condition remains unexplored. In this work, we demonstrate that either absorption or optical gain precludes the first Kerker condition and, hence, the absence of backscattered radiation light, regardless of the size of the particle, incident wavelength, and incoming polarization. Finally, we derive the necessary prerequisites of the second Kerker condition of the zero forward light scattering, finding that optical gain is a compulsory requirement

Interplay between BMPs and Reactive Oxygen Species in Cell Signaling and Pathology

The integration of cell extrinsic and intrinsic signals is required to maintain appropriate cell physiology and homeostasis. Bone morphogenetic proteins (BMPs) are cytokines that belong to the transforming growth factor-β (TGF-β) superfamily, which play a key role in embryogenesis, organogenesis and regulation of whole-body homeostasis. BMPs interact with membrane receptors that transduce information to the nucleus through SMAD-dependent and independent pathways, including PI3K-AKT and MAPKs. Reactive oxygen species (ROS) are intracellular molecules derived from the partial reduction of oxygen. ROS are highly reactive and govern cellular processes by their capacity to regulate signaling pathways (e.g., NF-κB, MAPKs, KEAP1-NRF2 and PI3K-AKT). Emerging evidence indicates that BMPs and ROS interplay in a number of ways. BMPs stimulate ROS production by inducing NOX expression, while ROS regulate the expression of several BMPs. Moreover, BMPs and ROS influence common signaling pathways, including PI3K/AKT and MAPK. Additionally, dysregulation of BMPs and ROS occurs in several pathologies, including vascular and musculoskeletal diseases, obesity, diabetes and kidney injury. Here, we review the current knowledge on the integration between BMP and ROS signals and its potential applications in the development of new therapeutic strategies

ACVR1 function in health and disease

Activin A receptor type I (ACVR1) encodes for a bone morphogenetic protein type I receptor of the TGFβ receptor superfamily. It is involved in a wide variety of biological processes, including bone, heart, cartilage, nervous, and reproductive system development and regulation. Moreover, ACVR1 has been extensively studied for its causal role in fibrodysplasia ossificans progressiva (FOP), a rare genetic disorder characterised by progressive heterotopic ossification. ACVR1 is linked to different pathologies, including cardiac malformations and alterations in the reproductive system. More recently, ACVR1 has been experimentally validated as a cancer driver gene in diffuse intrinsic pontine glioma (DIPG), a malignant childhood brainstem glioma, and its function is being studied in other cancer types. Here, we review ACVR1 receptor function and signalling in physiological and pathological processes and its regulation according to cell type and mutational status. Learning from different functions and alterations linked to ACVR1 is a key step in the development of interdisciplinary research towards the identification of novel treatments for these pathologies

Oclusión de la descendente anterior evaluada con cardio-TC

We introduce the clinical case of a patient with advanced coronary artery disease with complete left descending coronary artery occlusion in which CT scan allowed to evaluate the vessel distal to the occlusion and to choose the best coronary revascularization option. This case is a great example about how CT scan can be useful in the evaluation in selected cases of complex coronary disease.Se presenta el caso de un paciente con enfermedad coronaria avanzada y oclusión de la arteria descendente anterior en el que la cardio-TC permitió valorar el vaso distal a la oclusión y planifi car las opciones de revascularización. El caso es un buen ejemplo de cómo la cardio-TC puede complementar a la coronariografía convencional en algunos casos de enfermedad coronaria compleja