Publications by authors named "Amber C Howard"

As the most energetically expensive cellular process, translation must be finely tuned to environmental conditions. Dietary restriction attenuates signaling through the nutrient sensing mTOR pathway, which reduces translation and redirects resources to preserve the soma. These responses are associated with increased lifespan but also anabolic impairment, phenotypes also observed when translation is genetically suppressed.

View Article and Find Full Text PDF

Genetic changes resulting in increased life span are often positively associated with enhanced stress resistance and somatic maintenance. A recent study found that certain long-lived Caenorhabditis elegans mutants spent a decreased proportion of total life in a healthy state compared with controls, raising concerns about how the relationship between health and longevity is assessed. We evaluated seven markers of health and two health-span models for their suitability in assessing age-associated health in invertebrates using C elegans strains not expected to outperform wild-type animals.

View Article and Find Full Text PDF

Although certain methods of lowering and/or altering mRNA translation are associated with increased lifespan, the mechanisms underlying this effect remain largely unknown. We previously showed that the increased lifespan conferred by reducing expression of eukaryotic translation initiation factor 4G (eIF4G/IFG-1) enhances survival under starvation conditions while shifting protein expression toward factors involved with maintaining ER-dependent protein and lipid balance. In this study, we investigated changes in ER homeostasis and found that lower eIF4G/IFG-1 increased survival under conditions of ER stress.

View Article and Find Full Text PDF

Plasma membrane disruptions occur in mechanically active tissues such as the epidermis and can lead to cell death if the damage remains unrepaired. Repair occurs through fusion of vesicle patches to the damaged membrane region. The enzyme phospholipase D (PLD) is involved in membrane traffickiing; therefore, the role of PLD in membrane repair was investigated.

View Article and Find Full Text PDF

Severe vitamin E deficiency results in lethal myopathy in animal models. Membrane repair is an important myocyte response to plasma membrane disruption injury as when repair fails, myocytes die and muscular dystrophy ensues. Here we show that supplementation of cultured cells with α-tocopherol, the most common form of vitamin E, promotes plasma membrane repair.

View Article and Find Full Text PDF

Objective: Skeletal muscle myopathy is a common diabetes complication. One possible cause of myopathy is myocyte failure to repair contraction-generated plasma membrane injuries. Here, we test the hypothesis that diabetes induces a repair defect in skeletal muscle myocytes.

View Article and Find Full Text PDF

Receptor for advanced glycation end products (RAGE), an immunoglobin superfamily cell surface receptor, contributes to the vascular pathology associated with multiple disorders, including Alzheimer disease (AD), diabetic complications, and inflammatory conditions. However, the underlying mechanisms remain largely unclear. Here, using the human umbilical vein endothelial cell line (ECV-304) expressing human RAGE, we report that RAGE expression leads to an altered F-actin organization and impaired membrane resealing.

View Article and Find Full Text PDF