Therapeutic Potential of Intermittent Hypoxia in Atrial Fibrillation.

Intermittent hypoxia (IH) has been extensively studied in recent years, demonstrating adverse and beneficial effects on several physiological systems. However, the precise mechanism underlying its cardiac effects on the heart remains unclear. This study aims to explore the effect of treatment on atrial fibrillation under IH conditions, providing data that can potentially be used in the treatment of heart disease.

Protective effect of empagliflozin against palmitate-induced lipotoxicity through AMPK in H9c2 cells.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have recently emerged as novel cardioprotective agents. However, their direct impact on cardiomyocyte injury is yet to be studied. In this work, we investigate the underlying molecular mechanisms of empagliflozin (EMPA), an SGLT2 inhibitor, in mitigating palmitate (PA)-induced cardiomyocyte injury in H9c2 cells.

Human primary myoblasts derived from paraspinal muscle reflect donor age as an experimental model of sarcopenia.

Background: Low back pain is a general phenomenon of aging, and surgery is an unavoidable choice to relieve severe back pain. The discarded surgical site during surgery is of high value for muscle and muscle-related research. This study investigated the age-dependent properties of patients' paraspinal muscles at the cellular level.

Three-Dimensional Cell Culture System for Tendon Tissue Engineering.

Tendon, connective tissue between bone and muscle has unique component of the musculoskeletal system. It plays important role for transporting mechanical stress from muscle to bone and enabling locomotive motion of the body. There are some restoration capacities in the tendon tissue, but the injured tendons are not completely regenerated after acute and chronic tendon injury.

Knockdown of deleterious miRNA in progenitor cell-derived small extracellular vesicles enhances tissue repair in myocardial infarction.

Small extracellular vesicles (sEVs) play a critical role in cardiac cell therapy by delivering molecular cargo and mediating cellular signaling. Among sEV cargo molecule types, microRNA (miRNA) is particularly potent and highly heterogeneous. However, not all miRNAs in sEV are beneficial.

Genome-wide analysis of a cellular exercise model based on electrical pulse stimulation.

Skeletal muscle communicates with other organs via myokines, which are secreted by muscle during exercise and exert various effects. Despite much investigation of the exercise, the underlying molecular mechanisms are still not fully understood. Here, we applied an in vitro exercise model in which cultured C2C12 myotubes were subjected to electrical pulse stimulation (EPS), which mimics contracting muscle.

skeletal muscle models for type 2 diabetes.

Type 2 diabetes mellitus, a metabolic disorder characterized by abnormally elevated blood sugar, poses a growing social, economic, and medical burden worldwide. The skeletal muscle is the largest metabolic organ responsible for glucose homeostasis in the body, and its inability to properly uptake sugar often precedes type 2 diabetes. Although exercise is known to have preventative and therapeutic effects on type 2 diabetes, the underlying mechanism of these beneficial effects is largely unknown.

Transglutaminase 2 mediates UVB-induced matrix metalloproteinase-1 expression by inhibiting nuclear p65 degradation in dermal fibroblasts.

Matrix metalloproteinases (MMPs) play a key role in tissue remodelling by cleaving extracellular matrix (ECM) components. In the skin, UV irradiation increases expression of MMPs that causes dysregulation of ECM homeostasis in dermis, leading to acceleration of skin aging. However, the mediator(s) that links UV irradiation to the upregulation of MMPs have not been fully defined.

Pancreatic cancer induces muscle wasting by promoting the release of pancreatic adenocarcinoma upregulated factor.

Cancer cachexia is a highly debilitating condition characterized by weight loss and muscle wasting that contributes significantly to the morbidity and mortality of pancreatic cancer. The factors that induce cachexia in pancreatic cancer are largely unknown. We previously showed that pancreatic adenocarcinoma upregulated factor (PAUF) secreted by pancreatic cancer cells is responsible for tumor growth and metastasis.

FABP3-mediated membrane lipid saturation alters fluidity and induces ER stress in skeletal muscle with aging.

Sarcopenia is characterized by decreased skeletal muscle mass and function with age. Aged muscles have altered lipid compositions; however, the role and regulation of lipids are unknown. Here we report that FABP3 is upregulated in aged skeletal muscles, disrupting homeostasis via lipid remodeling.

A subset of microRNAs in the Dlk1-Dio3 cluster regulates age-associated muscle atrophy by targeting Atrogin-1.

Background: The microRNAs (miRNAs) down-regulated in aged mouse skeletal muscle were mainly clustered within the delta-like homologue 1 and the type III iodothyronine deiodinase (Dlk1-Dio3) genomic region. Although clustered miRNAs are coexpressed and regulate multiple targets in a specific signalling pathway, the function of miRNAs in the Dlk1-Dio3 cluster in muscle aging is largely unknown. We aimed to ascertain whether these miRNAs play a common role to regulate age-related muscle atrophy.

miR-3074-3p promotes myoblast differentiation by targeting Cav1.

Muscle fibers are generally formed as multinucleated fibers that are differentiated from myoblasts. Several reports have identified transcription factors and proteins involved in the process of muscle differentiation, but the roles of microRNAs (miRNAs) in myogenesis remain unclear. Here, comparative analysis of the miRNA expression profiles in mouse myoblasts and gastrocnemius (GA) muscle uncovered miR-3074-3p as a novel miRNA showing markedly reduced expression in fully differentiated adult skeletal muscle.

Two-Dimensionally Stretchable Organic Light-Emitting Diode with Elastic Pillar Arrays for Stress Relief.

Recent advanced studies on flexible and stretchable electronic devices and optoelectronics have made possible a variety of soft and more functional electronic devices. With consumer demand for highly functional or free-form displays, high flexibility and stretchability in light-emitting devices are needed. Herein, we developed a unique structure of stretchable substrates with pillar arrays to reduce the stress on the active area of devices when strain is applied.

Fibertronic Organic Light-Emitting Diodes toward Fully Addressable, Environmentally Robust, Wearable Displays.

Significant potential of electronic textiles for wearable applications has triggered active studies of luminescent fibers toward smart textile displays. In spite of notable breakthroughs in the lighting fiber technology, a class of information displays with a luminescent fiber network is still underdeveloped due to several formidable challenges such as limited electroluminescence fiber performance, acute vulnerability to chemical and mechanical factors, and lack of decent engineering schemes to form fibers with robust interconnectable pixels for two-dimensional matrix addressing. Here, we present a highly feasible strategy for organic light-emitting diode (OLED) fiber-based textile displays that can overcome these issues by implementing prominent solution options including compatible fabrication method of OLED pixel arrays on adapted fiber configurations and chemically/mechanically sturdy but electrically conductive passivation system.

Comparative molecular analysis of endurance exercise in vivo with electrically stimulated in vitro myotube contraction.

Exercise has positive effects on health and improves a variety of disease conditions. An in vitro model of exercise has been developed to better understand its molecular mechanisms. While various conditions have been used to mimic in vivo exercise, no specific conditions have matched a specific type of in vivo exercise.

Conserved but flexible modularity in the zebrafish skull: implications for craniofacial evolvability.

Morphological variation is the outward manifestation of development and provides fodder for adaptive evolution. Because of this contingency, evolution is often thought to be biased by developmental processes and functional interactions among structures, which are statistically detectable through forms of covariance among traits. This can take the form of substructures of integrated traits, termed modules, which together comprise patterns of variational modularity.

Real-Time Monitoring of Glutathione in Living Cells Reveals that High Glutathione Levels Are Required to Maintain Stem Cell Function.

The core functions of stem cells (SCs) are critically regulated by their cellular redox status. Glutathione is the most abundant non-protein thiol functioning as an antioxidant and a redox regulator. However, an investigation into the relationship between glutathione-mediated redox capacity and SC activities is hindered by lack of probe.

Amperometric Detection of Conformational Change of Proteins Using Immobilized-Liposome Sensor System.

An immobilized liposome electrode (ILE)-based sensor was developed to quantify conformational changes of the proteins under various stress conditions. The ILE surface was characterized by using a tapping-mode atomic force microscopy (TM-AFM) to confirm surface immobilization of liposome. The uniform layer of liposome was formed on the electrode.

Transglutaminase 2 mediates UV-induced skin inflammation by enhancing inflammatory cytokine production.

UV irradiation elicits acute inflammation in the skin by increasing proinflammatory cytokine production in keratinocytes. However, the downstream protein target(s) that link UV radiation to the activation of signaling pathways responsible for cytokine expression have not been fully elucidated. In this study, we report a novel role of transglutaminase 2 (TG2), a member of the TG enzyme family whose activities are critical for cornified envelope formation, in mediating UV-induced inflammation.

Sulforaphane prevents dexamethasone-induced muscle atrophy via regulation of the Akt/Foxo1 axis in C2C12 myotubes.

Muscle atrophy occurs in various catabolic conditions, including hormone imbalance, severe injury, sepsis, cancer, and aging. Dexamethasone (DEX) is a synthetic glucocorticoid and is used an anti-inflammatory agent. However, when chronically used, it is accompanied by side effects, such as, muscle atrophy, diabetes mellitus, and obesity.

Anticancer Effects of a Korean Herbal Medicine Formula (H9) via AMPK and HER2-PI3K/Akt Signaling in Breast Cancer Cells.

An H9 is a formula of nine medicinal herbs derived from Osuyubujaijung-tang, a traditional Korean prescription for Soeumin constitution. In our previous study, H9 showed anticancer effects against breast cancer and non-small-cell lung cancer. However, the underlying mechanisms of these effects have not yet been elucidated.

Therapeutic Mechanisms of Human Adipose-Derived Mesenchymal Stem Cells in a Rat Tendon Injury Model.

Background: Although survival of transplanted stem cells in vivo and differentiation of stem cells into tenocytes in vitro have been reported, there have been no in vivo studies demonstrating that mesenchymal stem cells (MSCs) could secrete their own proteins as differentiated tenogenic cells. Purpose/Hypothesis: Using a xenogeneic MSC transplantation model, we aimed to investigate whether MSCs could differentiate into the tenogenic lineage and secrete their own proteins. The hypothesis was that human MSCs would differentiate into the human tenogenic lineage and the cells would be able to secrete human-specific proteins in a rat tendon injury model.

Docosahexaenoic acid-mediated protein aggregates may reduce proteasome activity and delay myotube degradation during muscle atrophy in vitro.

Proteasomes are the primary degradation machinery for oxidatively damaged proteins that compose a class of misfolded protein substrates. Cellular levels of reactive oxygen species increase with age and this cellular propensity is particularly harmful when combined with the age-associated development of various human disorders including cancer, neurodegenerative disease and muscle atrophy. Proteasome activity is reportedly downregulated in these disease conditions.

Transglutaminase 2 is dispensable but required for the survival of mice in dextran sulfate sodium-induced colitis.

Transglutaminase 2 (TG2) is a ubiquitously expressed enzyme that catalyzes crosslinking, polyamination or deamidation of glutamine residues in proteins. It has been reported that TG2 is involved in the pathogenesis of various inflammatory diseases including celiac disease, pulmonary fibrosis, cystic fibrosis, multiple sclerosis and sepsis. Recently, using a mouse model of bleomycin-induced lung fibrosis, we showed that TG2 is required to trigger inflammation via the induction of T helper type 17 (Th17) cell differentiation in response to tissue damage.