ABSTRACT
Individuals with spinal cord injuries or disorders (SCI/D), whether of traumatic or nontraumatic cause, require multidisciplinary management by their care team to achieve optimal health outcomes. SCI/D is relatively rare in the general population and primary care providers (PCPs) may not have extensive experience managing people with these disorders. Spinal cord injuries, impair the body's autonomic and biomechanical performance by interrupting the communications to and from major bodily systems. This article provides a framework to help PCPs understand how these changes impact their patient's physiologic function and subsequent risks for health complications with guidance for initial treatment approaches.
Subject(s)
Patient Care Management/methods , Spinal Cord Injuries , Chronic Disease , Humans , Patient Care Team/organization & administration , Spinal Cord Injuries/physiopathology , Spinal Cord Injuries/therapyABSTRACT
Integrin-signaling complexes play important roles in cytoskeletal organization and cell adhesion in many species. Components of the integrin-signaling complex have been linked to aging in both Caenorhabditis elegans and Drosophila melanogaster, but the mechanism underlying this function is unknown. Here, we investigated the role of integrin-linked kinase (ILK), a key component of the integrin-signaling complex, in lifespan determination. We report that genetic reduction of ILK in both C. elegans and Drosophila increased resistance to heat stress, and led to lifespan extension in C. elegans without majorly affecting cytoskeletal integrity. In C. elegans, longevity and thermotolerance induced by ILK depletion was mediated by heat-shock factor-1 (HSF-1), a major transcriptional regulator of the heat-shock response (HSR). Reduction in ILK levels increased hsf-1 transcription and activation, and led to enhanced expression of a subset of genes with roles in the HSR. Moreover, induction of HSR-related genes, longevity and thermotolerance caused by ILK reduction required the thermosensory neurons AFD and interneurons AIY, which are known to play a critical role in the canonical HSR. Notably, ILK was expressed in neighboring neurons, but not in AFD or AIY, implying that ILK reduction initiates cell nonautonomous signaling through thermosensory neurons to elicit a noncanonical HSR. Our results thus identify HSF-1 as a novel effector of the organismal response to reduced ILK levels and show that ILK inhibition regulates HSF-1 in a cell nonautonomous fashion to enhance stress resistance and lifespan in C. elegans.
Subject(s)
Caenorhabditis elegans Proteins/physiology , Caenorhabditis elegans/physiology , Heat-Shock Response/physiology , Longevity/physiology , Protein Serine-Threonine Kinases/physiology , Transcription Factors/physiology , Animals , Caenorhabditis elegans/genetics , Caenorhabditis elegans/metabolism , Caenorhabditis elegans Proteins/genetics , Heat-Shock Response/genetics , Longevity/genetics , Protein Serine-Threonine Kinases/genetics , Signal Transduction , Transcription Factors/geneticsABSTRACT
Autophagy is a cellular recycling process that has an important anti-aging role, but the underlying molecular mechanism is not well understood. The mammalian transcription factor EB (TFEB) was recently shown to regulate multiple genes in the autophagy process. Here we show that the predicted TFEB orthologue HLH-30 regulates autophagy in Caenorhabditis elegans and, in addition, has a key role in lifespan determination. We demonstrate that hlh-30 is essential for the extended lifespan of Caenorhabditis elegans in six mechanistically distinct longevity models, and overexpression of HLH-30 extends lifespan. Nuclear localization of HLH-30 is increased in all six Caenorhabditis elegans models and, notably, nuclear TFEB levels are augmented in the livers of mice subjected to dietary restriction, a known longevity-extending regimen. Collectively, our results demonstrate a conserved role for HLH-30 and TFEB in autophagy, and possibly longevity, and identify HLH-30 as a uniquely important transcription factor for lifespan modulation in Caenorhabditis elegans.