RESUMEN
Dystrophin protein in association with several other cellular proteins and glycoproteins leads to the formation of a large multifaceted protein complex at the cell membrane referred to as dystrophin glycoprotein complex (DGC), that serves distinct functions in cell signaling and maintaining the membrane stability as well as integrity. In accordance with this, several findings suggest exquisite role of DGC in signaling pathways associated with cell development and/or maintenance of homeostasis. In the present review, we summarize the established facts about the various components of this complex with emphasis on recent insights into specific contribution of the DGC in cell signaling at the membrane. We have also discussed the recent advances made in exploring the molecular associations of DGC components within the cells and the functional implications of these interactions. Our review would help to comprehend the composition, role, and functioning of DGC and may lead to a deeper understanding of its role in several human diseases.
Asunto(s)
Membrana Celular/genética , Complejo de Proteínas Asociado a la Distrofina/genética , Distrofina/genética , Glicoproteínas/genética , Membrana Celular/química , Distrofina/química , Complejo de Proteínas Asociado a la Distrofina/química , Humanos , Complejos Multiproteicos/química , Complejos Multiproteicos/genética , Músculo Esquelético/química , Músculo Esquelético/metabolismo , Transducción de SeñalRESUMEN
Mitochondria play a central role in cellular physiology. Besides their classic function of energy metabolism, mitochondria are involved in multiple cell functions, including energy distribution through the cell, energy/heat modulation, regulation of reactive oxygen species (ROS), calcium homeostasis, and control of apoptosis. Simultaneously, mitochondria are the main producer and target of ROS with the result that multiple mitochondrial diseases are related to ROS-induced mitochondrial injuries. Increased free radical generation, enhanced mitochondrial inducible nitric oxide synthase (iNOS) activity, enhanced nitric oxide (NO) production, decreased respiratory complex activity, impaired electron transport system, and opening of mitochondrial permeability transition pores have all been suggested as factors responsible for impaired mitochondrial function. Because of these, neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), and aging, are caused by ROS-induced mitochondrial dysfunctions. Melatonin, the major hormone of the pineal gland, also acts as an anti-oxidant and as a regulator of mitochondrial bioenergetic function. Melatonin is selectively taken up by mitochondrial membranes, a function not shared by other anti-oxidants, and thus has emerged as a major potential therapeutic tool for treating neurodegenerative disorders. Multiple in vitro and in vivo experiments have shown the protective role of melatonin for preventing oxidative stress-induced mitochondrial dysfunction seen in experimental models of PD, AD, and HD. With these functions in mind, this article reviews the protective role of melatonin with mechanistic insights against mitochondrial diseases and suggests new avenues for safe and effective treatment modalities against these devastating neurodegenerative diseases. Future insights are also discussed.
