Structure, regulation, and physiological functions of NADPH oxidase 5 (NOX5).

NOX5 is the last member of the NADPH oxidase (NOXs) family to be identified and presents some specific characteristics differing from the rest of the NOXs. It contains four Ca2+ binding domains at the N-terminus and its activity is regulated by the intracellular concentration of Ca2+. NOX5 generates superoxide (O2•-) using NADPH as a substrate, and it modulates functions related to processes in which reactive oxygen species (ROS) are involved. Those functions appear to be detrimental or beneficial depending on the level of ROS produced. For example, the increase in NOX5 activity is related to the development of various oxidative stress-related pathologies such as cancer, cardiovascular, and renal diseases. In this context, pancreatic expression of NOX5 can negatively alter insulin action in high-fat diet-fed transgenic mice. This is consistent with the idea that the expression of NOX5 tends to increase in response to a stimulus or a stressful situation, generally causing a worsening of the pathology. On the other hand, it has also been suggested that it might have a positive role in preparing the body for metabolic stress, for example, by inducing a protective adipose tissue adaptation to the excess of nutrients supplied by a high-fat diet. In this line, its endothelial overexpression can delay lipid accumulation and insulin resistance development in obese transgenic mice by inducing the secretion of IL-6 followed by the expression of thermogenic and lipolytic genes. However, as NOX5 gene is not present in rodents and human NOX5 protein has not been crystallized, its function is still poorly characterized and further extensive research is required.

Immune-Mediated Disorders Affecting the Spinal Cord and the Spine.

PURPOSE OF REVIEW: To review the most recent advances and provide a description of the most common autoimmune diseases causing myelitis and selective spine disorders. The ultimate goal of this article is to facilitate the prompt recognition of these diseases. RECENT FINDINGS: The recent discovery of biomarkers such as aquaporin 4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibodies has changed our understanding of autoimmune diseases affecting the spinal cord as well as their treatment and outcomes. Autoimmune neurology is an increasingly evolving field that encompasses a broad spectrum of autoimmune-inflammatory diseases of the central nervous system (CNS) and peripheral nervous system (PNS). Autoimmune disorders of the spinal cord are a heterogeneous group of myelopathies with a broad differential diagnosis and many of them have been recently identified. Prompt recognition of these myelopathies is important as some of them are treatable, which could improve patient outcomes and prevent disability.