Effects of electrotactic exercise and antioxidant EUK-134 on oxidative stress relief in Caenorhabditis elegans.

Antioxidant uptake and regular exercise are two well-acknowledged measures used for rejuvenation and oxidative stress elimination. Previous studies have revealed that moderate exercise mildly increases intracellular signaling oxidant levels and strengthens the ability of an organism to deal with escalating oxidative stress by upregulating antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase. Antioxidant supplementation directly scavenges intracellular reactive oxygen species (ROS) to reduce oxidative stress. However, research to understand the impacts of these enzymes on mitigating oxidative stress from the perspective of simple animals is limited. Herein, we show that exercise combined with antioxidant supplementation ameliorates the physiological phenotypes and markers of aging in wild-type and SOD/CAT-deficient Caenorhabditis elegans. We discovered that treated wild-type and gene-deficient worms show better survivorship, reproduction, and motility compared with their control counterparts. Assays of biochemical indices revealed that variations in sod-3 expression under different stress levels imply an inducible enzyme response resulting from exercise training and antioxidant supplementation. In addition, induced ROS resistance obtained from any type of treatment could persist for several days even after treatment cessation, thus suggesting a potential long-term antioxidative stress effect. Our findings confirm that exercise, antioxidant supplementation, and their combination could significantly improve the ability of C. elegans to withstand adverse stress. Our observations provide promising insights into future therapies of anti-oxidative stress in higher animals.

Cystic Fibrosis Transmembrane Conductance Regulator: A Possible New Target for Photodynamic Therapy Enhances Wound Healing.

Objective: Cell migration is an essential process in skin wound healing. Photodynamic therapy (PDT) enhances wound healing by photoactivating a photosensitizer with a specific wavelength of light. Cystic fibrosis transmembrane conductance regulator (CFTR) is an ion channel expressed in multiple layers of keratinocytes. Recent studies showed that the activation of CFTR-related downstream signaling affects skin wound healing. We examined whether indocyanine green (ICG)-mediated PDT-enhanced cell migration is related to CFTR activation. Approach: The spatial and temporal expression levels of CFTR and proteins involved in focal adhesion, including focal adhesion kinase (FAK) and paxillin, were evaluated during cell migration in vitro and in vivo for wound healing. Results: ICG-PDT-conditioned medium collected from cells exposed to 5 J/cm2 near-infrared light in the presence of 100 µg/mL ICG activated CFTR and enhanced HaCaT cell migration. The expression of phosphorylated FAK Tyr861 and phosphorylated paxillin in focal adhesions was spatially and temporally regulated in parallel by ICG-PDT-conditioned medium. Curcumin, a nonspecific activator of CFTR, further increased PDT-enhanced cell migration, whereas inhibition of CFTR and FAK delayed cell migration. The involvement of CFTR in ICG-PDT-enhanced skin wound healing was confirmed in a mouse back skin wound model. Innovation: CFTR is a potential new therapeutic target in ICG-PDT to enhance wound healing. Conclusion: ICG-PDT-enhanced cell migration may be related to activation of the CFTR and FAK pathway. Conditioned medium collected from ICG-PDT may be useful for treating patients with chronic skin ulcer by regulating CFTR expression in keratinocytes.

CO2 Delivery To Accelerate Incisional Wound Healing Following Single Irradiation of Near-Infrared Lamp on the Coordinated Colloids.

Traditional wound care methods include wound infection control, adequate nutritional supplements, education of changing position every 2-3 h to avoid tissue hypoxia, vacuum assistant closure, debridement, skin graft, and tissue flap. Electric current stimulation, ultrasound, laser, and hydrotherapy have emerged as adjuvant therapies. However, most, if not all, of these therapies are expensive, and the treatment results are variable. The development of the active methods to improve wound healing is mandatory. CO2 administration has been known to improve microcirculation and local oxygen supply that are beneficial to wound healing. Here, the metal ion-ligand coordination nanoarchitecture was designed to reveal NIR light-induced CO2 generation for wound healing. The administration simply topically dropped the colloidal solution on the incisional wound, followed by exposure of near-infrared (NIR) lamp to yield CO2, resulting in the observation of the accelerated wound healing.

Loss of Egr-1 sensitizes pancreatic ß-cells to palmitate-induced ER stress and apoptosis.

UNLABELLED: Pancreatic ß-cells are particularly susceptible to fatty-acid-induced endoplasmic reticulum (ER) stress and apoptosis. To understand how ß-cells sense fatty acid stimuli and translate into a long-term adaptive response, we investigated whether palmitic acid (PA) regulates early growth response-1 (Egr-1), an immediate-early transcription factor, which is induced by many environmental stimuli and implicated in cell proliferation, differentiation, and apoptosis. We found that Egr-1 was rapidly and transiently induced by PA in MIN6 insulinoma cells, which was accompanied by calcium influx and ERK1/2 phosphorylation. Calcium chelation and MEK1/2 inhibition blocked PA-induced Egr-1 upregulation, suggesting that PA induces Egr-1 expression through a calcium influx-MEK1/2-ERK1/2 cascade. Knockdown of Egr-1 increased PA-induced caspase-3 activation and ER stress markers and decreased PA-induced Akt phosphorylation and insulin secretion and signaling. Akt replenishment and insulin supplementation rescued PA-induced apoptosis in Egr-1 knockdown cells. These results suggest that the absence of Egr-1 loses its ability to couple the short-term insulin/Akt pathway to long-term survival adaptation. Finally, Egr-1-deficient mouse islets are more susceptible to ex vivo stimuli of apoptosis. In human pancreatic tissues, EGR1 expression correlated with expression of ER stress markers and anti-apoptotic gene. In conclusion, Egr-1 is induced by PA and further attempts to rescue ß-cells from ER stress and apoptosis through improving insulin/Akt signaling. Our study underscores Egr-1 as a critical early sensor in pancreatic ß-cells to translate fatty acid stimuli into a cellular adaptation mechanism. KEY MESSAGE: PA stimulates Egr-1 expression via a calcium influx-MEK1/2-ERK1/2-Elk-1 cascade. Egr-1 attenuates PA-induced ER stress and apoptosis. Egr-1 maintains Akt survival pathway to protect ß-cells from PA-induced apoptosis. Egr-1-deficient islets are prone to ex vivo stimuli of apoptosis. Human EGR1 expression correlates with genes for ER stress and anti-apoptosis.