Lipofundin-Induced Hyperlipidemia Promotes Oxidative Stress and Atherosclerotic Lesions in New Zealand White Rabbits

Atherosclerosis represents a major cause of death in the world. It is known that Lipofundin 20% induces atherosclerotic lesions in rabbits, but its effects on serum lipids behaviour and redox environment have not been addressed. In this study, New Zealand rabbits were treated with 2 mL/kg of Lipofundin for 8 days. Then, redox biomarkers and serum lipids were determined spectrophotometrically. On the other hand, the development of atherosclerotic lesions was confirmed by eosin/hematoxylin staining and electron microscopy. At the end of the experiment, total cholesterol, triglycerides, cholesterol-LDL, and cholesterol-HDL levels were significantly increased. Also, a high index of biomolecules damage, a disruption of both enzymatic and nonenzymatic defenses, and a reduction of nitric oxide were observed. Our data demonstrated that Lipofundin 20% induces hyperlipidemia, which promotes an oxidative stress state. Due to the importance of these phenomena as risk factors for atherogenesis, we suggest that Lipofundin induces atherosclerosis mainly through these mechanisms

C-Phycocyanin and Phycocyanobilin as Remyelination Therapies for Enhancing Recovery in Multiple Sclerosis and Ischemic Stroke: A Preclinical Perspective

Myelin loss has a crucial impact on behavior disabilities associated to Multiple Sclerosis (MS) and Ischemic Stroke (IS). Although several MS therapies are approved, none of them promote remyelination in patients, limiting their ability for chronic recovery. With no available therapeutic options, enhanced demyelination in stroke survivors is correlated with a poorer behavioral recovery. Here, we show the experimental findings of our group and others supporting the remyelinating effects of C-Phycocyanin (C-PC), the main biliprotein of Spirulina platensis and its linked tetrapyrrole Phycocyanobilin (PCB), in models of these illnesses. C-PC promoted white matter regeneration in rats and mice affected by experimental autoimmune encephalomyelitis. Electron microscopy analysis in cerebral cortex from ischemic rats revealed a potent remyelinating action of PCB treatment after stroke. Among others biological processes, we discussed the role of regulatory T cell induction, the control of oxidative stress and pro-inflammatory mediators, gene expression modulation and COX-2 inhibition as potential mechanisms involved in the C-PC and PCB effects on the recruitment, differentiation and maturation of oligodendrocyte precursor cells in demyelinated lesions. The assembled evidence supports the implementation of clinical trials to demonstrate the recovery effects of C-PC and PCB in these diseases

Cuantificación por inmunomicroscopía electrónica del efecto terapéutico del EGF en úlceras del pie diabético

Introducción: la Inmunomicroscopía electrónica cuantitativa se aplicó recientemente en el estudio de la cuantificación de las distribuciones de determinadas proteínas en diferentes organelos celulares en fibroblastos de Úlceras de pie diabético tratados con el Factor de crecimiento epidérmico en humanos. Objetivo: el presente se enfoca en los resultados relacionados con una molécula clave [el antígeno nuclear de proliferación celular] en la señalización inducida por el Factor de crecimiento epidérmico. Desarrollo: las muestras de Úlceras de pie diabético se analizaron por la inmunomicroscopía electrónica cuantitativa. Las referencias se obtuvieron de la Base de datos Pubmed. En concordancia con una afectación funcional de la señalización mediada por el Factor de crecimiento epidérmico en el tejido de granulación de los individuos diabéticos, se observó poca detección del antígeno nuclear de proliferación celular en los fibroblastos. No obstante, el tratamiento de las Úlceras de pie diabético con el Factor de crecimiento epidérmico indujo una activación temprana del antígeno nuclear de proliferación celular en el núcleo de los fibroblastos de las Úlceras de pie diabético. Se observó, además, un incremento en el inmunomarcaje del antígeno nuclear de proliferación celular en las mitocondrias de los fibroblastos en tiempos tardíos después de la inoculación del Factor de crecimiento epidérmico. Conclusiones: esta investigación demostró la utilidad y el valor de la cuantificación de las distribuciones de inmunomarcaje en organelos celulares para el estudio de las vías de señalización intracelulares de relevancia terapéutica

Cicatrización de heridas cutáneas y papel de los miofibroblastos

Objetivo: realizar una revisión de las características fundamentales de la respuesta de cicatrización de heridas (RCH) cutáneas agudas y crónicas. Materiales y Métodos: la información se obtuvo de la base de datos pubmed y de los trabajos de inves-tigación de los autores. Resultados: la RCH cutáneas se desarrolla en cuatro fases secuenciales: hemostasia, inflamación, proliferación y remodelación. Primero ocurre la activación de fibroblastos, acumulación de un infiltrado celular inflamatorio que incluye a los miofibroblastos y la alteración de la matriz extracelular local (MEC). Después ocurre proliferación de los miofibroblastos, angiogénesis y proliferación de las células epiteliales. Finalmente tiene lugar el cierre de la herida y el restablecimiento de la arquitectura normal. Las heridas crónicas no siguen el patrón normal de reparación y no ocurre la cicatrización. Esto conduce a condiciones patológicas como las úlceras del pie diabético. Los miofibroblastos desempeñan un papel clave y su evolución coincide con los eventos de la RCH. Primero ocurre la trans-diferenciación que involucra la conversión de los fibroblastos en reposo a miofibroblastos que proliferan, son fibrogénicos y contráctiles. Posteriormente ocurre la perpetuación del fenotipo activado que incluye respuestas de fibrogénesis, proliferación, contractibilidad, liberación de citoquinas proinflamatorias, quimotaxis y degradación de la MEC. La resolución involucra la remoción del exceso de MEC y de los miofibroblastos. La eliminación de estos ocurre por tres mecanismos fundamentales: apoptosis, senescencia y reversión al fenotipo de fibroblastos. Esto constituye un paso fundamental en la restitución de la integridad del tejido. Conclusiones: se presentó una revisión actualizada de la RCH fisiológica y patológica

Synthetic Growth Hormone-Releasing Peptides (GHRPs): A Historical Appraisal of the Evidences Supporting Their Cytoprotective Effects

Background: Growth hormone-releasing peptides (GHRPs) constitute a group of small synthetic peptides that stimulate the growth hormone secretion and the downstream axis activity. Mounting evidences since the early 1980s delineated unexpected pharmacological cardioprotective and cytoprotective properties for the GHRPs. However, despite intense basic pharmacological research, alternatives to prevent cell and tissue demise before lethal insults have remained as an empty niche in the clinical armamentarium. Here, we have rigorously reviewed the investigational development of GHRPs and their clinical niching perspectives. Methodology: PubMed/MEDLINE databases, including original research and review articles, were explored. The search design was date escalated from 1980 and included articles in English only. Results and Conclusions: GHRPs bind to two different receptors (GHS-R1a and CD36), which redundantly or independently exert relevant biological effects. GHRPs’ binding to CD36 activates prosurvival pathways such as PI-3K/AKT1, thus reducing cellular death. Furthermore, GHRPs decrease reactive oxygen species (ROS) spillover, enhance the antioxidant defenses, and reduce inflammation. These cytoprotective abilities have been revealed in cardiac, neuronal, gastrointestinal, and hepatic cells, representing a comprehensive spectrum of protection of parenchymal organs. Antifibrotic effects have been attributed to some of the GHRPs by counteracting fibrogenic cytokines. In addition, GHRP family members have shown a potent myotropic effect by promoting anabolia and inhibiting catabolia. Finally, GHRPs exhibit a broad safety profile in preclinical and clinical settings. Despite these fragmented lines incite to envision multiple pharmacological uses for GHRPs, especially as a myocardial reperfusion damage-attenuating candidate, this family of “drugable” peptides awaits for a definitive clinical niche

Diabetic Foot Ulcers and Epidermal Growth Factor: Revisiting the Local Delivery Route for a Successful Outcome

Soon after epidermal growth factor (EGF) discovery, some in vivo models appeared demonstrating its property to enhance cutaneous wound healing. EGF was the first growth factor (GF) introduced in the clinical arena as a healing enhancer, exerting its mitogenic effects on epithelial, fibroblastoid, and endothelial cells via a tyrosine kinase membrane receptor. Compelling evidences from the 90s documented that, for EGF, locally prolonged bioavailability and hourly interaction with the receptor were necessary for a successful tissue response. Eventually, the enthusiasm on the clinical use of EGF to steer the healing process was wiped out as the topical route to deliver proteins started to be questioned. The simultaneous in vivo experiments, emphasizing the impact of the parenterally administered EGF on epithelial and nonepithelial organs in terms of mitogenesis and cytoprotection, rendered the theoretical fundamentals for the injectable use of EGF and shaped the hypothesis that locally infiltrating the diabetic ulcers would lead to an effective healing. Although the diabetic chronic wounds microenvironment is hostile for local GFs bioavailability, EGF local infiltration circumvented the limitations of its topical application, thus expanding its therapeutic prospect. Our clinical pharmacovigilance and basic studies attest the significance of the GF local infiltration for chronic wounds healing