Nanostructured lipid carriers loaded with curcuminoids: Physicochemical characterization, in vitro release, ex vivo skin penetration, stability and antioxidant activity.

Four formulations of nanostructured lipid carriers (NLC) loaded with curcuminoids where prepared, testing two types of solid lipids (Compritol® 888 ATO and Precirol® ATO 5) and two kinds of stabilizers (poloxamer 407 and polysorbate 80). Particle size values between 111 and 214 nm and polydispersity indices < 0.3 were registered, with low Z potential values due to the nonionic character of the stabilizers. The results showed that the type of surfactant had an impact on the in vitro release rate and on the ex vivo skin permeation capability of curcuminoids. Polysorbate 80 delayed the release, but favors the transport of a higher amount of curcuminoids to the receptor solution during the ex vivo permeation studies than the systems with poloxamer 407. Confocal microscopy confirmed that all systems favored the penetration of curcuminoids to deeper layers of the skin and in a greater amount than curcuminoids in solution. Exposure of the systems to intense radiation caused the degradation of curcuminoids, without loss of antioxidant activity, confirming that the degradation products also function as antioxidants. The NLC prepared can be valuable carriers to enhance the penetration of curcuminoids into the skin, to treat different disorders and skin diseases.

Effect of resveratrol on mitochondrial activity in differentiated mature adipocytes / Efecto del resveratrol sobre la actividad mitocondrial en adipocitos maduros diferenciados

Obesity has reached epidemic proportions, the World Health Organization (WHO) estimates that there are more than 1,000 million overweight adults world-wide. Furthermore, obesity is characterized as an overgrowth of white adipose tissue as a result of adipocyte hypertrophy and hyperplasia. Mitochondria is considered the source of energy within the adipocyte, since it contains the molecular machinery, and it is involved in a large number of metabolic pathways, besides the transformation of chemical energy into adenosine triphosphate. Mitochondria shortage and adipocyte dysfunction result in an excessive accumulation of triacylglycerol in the cytoplasm, which determines an imbalance between energy production and energy expenditure. Resveratrol (RSV) is a polyphenol found in different plants and its effects have been associated with mitochondrial biogenesis. An adipogenesis in vitro model (3T3-L1 preadipocytes) was used, and these cells were differentiated into mature adipocytes. Subsequently the effect of RSV on the adipocytes morphology, the lipid content and mitochondrial activity was evaluated using microscopic and flow cytometry techniques. The effect of RSV on differentiated mature adipocytes, was characterized by the decrease in lipid content and the consequently declination of the mitochondrial activity. 3T3-L1 preadipocytes retained the differentiation ability until passage 18. The RSV at doses of 25 and 50 µM for 48 hours in differentiated mature adipocytes promoted the decreased in lipid content probably due to an increase in mitochondrial activity in the early hours of RSV exposure, causing the consequently declination of mitochondrial activity at the end of 48 hours.

La obesidad ha tomado dimensiones epidémicas globales y la Organización Mundial de la Salud estima que hay más de 1,000 millones de adultos con sobrepeso. Así mismo, la obesidad se ha caracterizado como la expansión del tejido adiposo blanco condicionada por la hipertrofia e/o hiperplasia de los adipocitos. La mitocondria es considerada la fuente de energía dentro del adipocito, debido a que contiene la maquinaria molecular que dirige, a través de diversas vías metabólicas, la transformación de la energía química en adenosíntrifosfato. La escasez de mitocondrias así como su disfunción en el adipocito, resulta en una acumulación excesiva de triacilgliceroles en el citoplasma, lo que condiciona un desequilibrio entre producción de energía y gasto energético. El resveratrol (RSV) es un polifenol que se encuentra en diferentes grupos de plantas y sus efectos se han asociado con la inducción de genes para la biogénesis mitocondrial. Se empleó un modelo de adipogénesis (in vitro) materializado por una línea celular de preadipocitos 3T3-L1, mismos que se diferenciaron a adipocitos maduros. Posteriormente se evaluó el efecto del RSV sobre la morfología, contenido lipídico y actividad mitocondrial en los adipocitos maduros diferenciados a través de las técnicas: microscopía invertida, confocal y citometría de flujo. El efecto del RSV sobre los adipocitos maduros diferenciados, se caracterizó por la disminución del contenido lipídico y consecuentemente de la actividad mitocondrial. Los preadipocitos 3T3-L1 conservaron la capacidad de diferenciación hasta el pase 18. Por otra parte, el resveratrol a dosis de 25 y 50 µM durante 48 horas en adipocitos maduros diferenciados, promueve una disminución en el contenido lipídico probablemente debido a un aumento de la actividad mitocondrial en las primeras horas de exposición al tratamiento, provocando la disminución de la actividad mitocondrial al término de 48 horas.

Papel de la hemooxigenasa-1 en las enfermedades neurodegenerativas / Role of hemeoxygenase-1 in the neurodegenerative disorders

Objetivo. Revisar evidencias de la participación de la hemooxigenasa-1 (HO-1) en enfermedades neurodegenerativas. Desarrollo. La HO cataliza la degradación del grupo hemo a monóxido de carbono, hierro y biliverdina. Se han caracterizado ampliamente dos isoformas de la HO: una inducible (HO-1) y una constitutiva (HO-2). Como la expresión de HO-1 confiere citoprotección en varias líneas celulares y en modelos animales bajo estrés oxidativo, se considera que la activación del gen de HO-1 es un mecanismo de defensa celular. En estudios post mortem en cerebro se ha encontrado un incremento en la expresión de la HO-1 en pacientes con enfermedades de Alzheimer, Parkinson y Huntington. Aunque no se han determinado la causa y el significado de este aumento, existen evidencias de que la sobreexpresión de la HO-1 contribuye a la acumulación de hierro en la mitocondria, lo que sugeriría que la expresión de la HO-1 tiene un efecto citotóxico. En contraste, hay evidencias de que la sobreexpresión de la HO-1 disminuye la muerte celular en ratones transgénicos y cultivos neuronales expuestos a compuestos neurotóxicos, lo que sugeriría que esta enzima tiene un papel citoprotector. Conclusión. Existe controversia sobre si la expresión de la HO-1 durante enfermedades neurodegenerativas confiere citoprotección o, por el contrario, promueve la neurodegeneración. Por tanto, es necesario continuar el estudio del papel de la HO-1 en modelos de daño neuronal

Aim. To review some evidences about the role of hemeoxygenase-1 (HO-1) in neurodegenerative disorders. Development. HO is the rate-limiting enzyme that catalyzes the conversion of heme into biliverdin, carbon monoxide, and free iron. They are the inducible HO-1 and the constitutive HO-2. A large body of evidence suggests that HO-1 confers cytoprotection against oxidative stress. Postmortem studies conducted in humans have revealed increase in HO-1 protein in association with Alzheimer disease, Parkinson disease and Huntington disease. It is unknown the meaning of that increase. Nevertheless, there are evidences indicating that the overexpression of HO-1 contributes to the pathological iron deposition suggesting a detrimental role of HO-1. In contrast, there are evidences indicating that the overexpression of HO-1 decreases the neurotoxin-induced cell death in transgenic mice and neuronal cultures suggesting a cytoprotective role of HO-1. Conclusion. It is controversial if the overexpression of HO-1 has a detrimental or cytoprotective role. Therefore, it is necessary to continue the study about the role of the HO-1 in neurodegenerative diseases

[Role of hemeoxygenase-1 in the neurodegenerative disorders]. / Papel de la hemooxigenasa-1 en las enfermedades neurodegenerativas.

AIM: To review some evidences about the role of hemeoxygenase-1 (HO-1) in neurodegenerative disorders. DEVELOPMENT: HO is the rate-limiting enzyme that catalyzes the conversion of heme into biliverdin, carbon monoxide, and free iron. They are the inducible HO-1 and the constitutive HO-2. A large body of evidence suggests that HO-1 confers cytoprotection against oxidative stress. Postmortem studies conducted in humans have revealed increase in HO-1 protein in association with Alzheimer disease, Parkinson disease and Huntington disease. It is unknown the meaning of that increase. Nevertheless, there are evidences indicating that the overexpression of HO-1 contributes to the pathological iron deposition suggesting a detrimental role of HO-1. In contrast, there are evidences indicating that the overexpression of HO-1 decreases the neurotoxin-induced cell death in transgenic mice and neuronal cultures suggesting a cytoprotective role of HO-1. CONCLUSION: It is controversial if the overexpression of HO-1 has a detrimental or cytoprotective role. Therefore, it is necessary to continue the study about the role of the HO-1 in neurodegenerative diseases.