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Background: Skeletal muscle atrophy significantly affects quality of life and has socio-economic and health implications. This study evaluates the effects of entacapone (ENT) on skeletal muscle atrophy linked with oxidative stress and proteolysis. Methods: C2C12 cells were treated with dexamethasone (Dex) to simulate muscle atrophy. Four murine models were employed: diaphragm atrophy from mechanical ventilation, Dex-induced atrophy, lipopolysaccharide (LPS)-induced atrophy, and hyperlipidemia-induced atrophy. Each model utilized entacapone (10 mg/kg), with sample sizes: Control (9), MV (11), MV + ENT (5) for diaphragm atrophy; Control (4), Dex (4), Dex + ENT (5) for Dex model; Control (4), LPS (4), LPS + ENT (5) for LPS model; and similar for hyperlipidemia. Measurements included muscle strength, myofiber cross-sectional area (CSA), proteolysis, oxidative stress markers [uperoxide dismutase 1 (SOD1), uperoxide dismutase 2 (SOD2), 4-hydroxynonenal (4-HNE)], and lipid levels. Results: Our findings confirm Dex-induced muscle atrophy, evidenced by increased expression of muscle atrophy-associated proteins, including Atrogin-1 and Murf-1, along with decreased diameter of C2C12 myotubes. Atrogin-1 levels rose by 660.6% (p < 0.05) in the Dex group compared to control, while entacapone reduced Atrogin-1 by 84.4% (p < 0.05). Similarly, Murf-1 levels increased by 365% (p < 0.05) in the Dex group and were decreased by 89.5% (p < 0.05) with entacapone. Dexamethasone exposure induces oxidative stress, evidenced by the upregulation of oxidative stress-related proteins Sod1, Sod2, and 4-HNE. Entacapone significantly reduced the levels of these oxidative stress markers, enhancing GSH-PX content by 385.6% (p < 0.05) compared to the Dex-treated group. Additionally, ENT effectively reduced the Dex-induced increase in MDA content by 63.98% (p < 0.05). Furthermore, entacapone effectively prevents the decline in diaphragm muscle strength and myofiber CSA in mice. It also mitigates diaphragm oxidative stress and protein hydrolysis. Additionally, entacapone exhibits the ability to attenuate lipid accumulation in the gastrocnemius muscle of hyperlipidemic mice and alleviate the reduction in muscle fiber CSA. Conclusion: Our findings suggest that entacapone is a promising therapeutic candidate for muscle atrophy, functioning through the reduction of oxidative stress, proteolysis, and lipid aggregation. Future research should explore the underlying mechanisms and potential clinical applications of entacapone in muscle-wasting conditions. [ABSTRACT FROM AUTHOR]

H2-free electrochemical hydrogenation of unsaturated organic compounds has garnered considerable attention as a low-carbon and efficient alternative to conventional thermocatalytic hydrogenation. However, in a traditional electrolytic cell, the compounds need to dissolve in the electrolyte before participating in the catalytic reactions, resulting in difficulties in enhancing the compounds' yield, as well as product separation and purification. A Pd membrane reactor offers a solution to these challenges by enabling the separation of a hydrogenation reaction into electrochemical and chemical processes. Here we summarize the processes of the Pd membrane reactor which drive the electrochemical hydrogenation of unsaturated compounds including gaseous reagents. We discuss various modification strategies for Pd catalysts, including the fabrication of Pd nanodendrites, incorporation of foreign metal layers, and formation of Pd alloys with other metals. These strategies aim to enhance catalytic activity by increasing the active area and fine-tuning reactant adsorption. We place significant emphasis on using this membrane reactor to hydrogenate unsaturated bonds, including C＝C, C≡C, C≡N, C＝O, and O＝O bonds and highlight distinct catalysts to enhance catalytic selectivity. Finally, we provide some perspectives on the challenges and outlook for other electrochemical hydrogenation reactions through the Pd membrane reactor. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (ZIBs) represent an attractive choice for energy storage. However, ZIBs suffer from dendrite growth and an irreversible consumption of Zn metal, leading to capacity degradation and a low lifetime. In this work, a zinc–alginate (ZA) hydrogel–polymer electrolyte (HGPE) with a non-porous structure was prepared via the solution-casting method and ion displacement reaction. The resulting ZA-based HGPE exhibits a high ionic conductivity (1.24 mS cm−1 at room temperature), excellent mechanical properties (28 MPa), good thermal and electrochemical stability, and an outstanding zinc ion transference number (0.59). The ZA-based HGPE with dense structure is proven to benefit the prevention of the uneven distribution of ion current and facilitates the reduction of excessive interfacial resistance within the battery. In addition, it greatly promotes the uniform deposition of zinc ions on the electrode, thereby inhibiting the growth of zinc dendrites. The corresponding zinc symmetric battery with ZA-based HGPE can be cycled stably for 800 h at a current density of 1 mA cm−2, demonstrating the stable and reversible zinc plating/stripping behaviors on the electrode surfaces. Furthermore, the quasi-solid-state ZIB with zinc, ZA-based HGPE, and Ca0.24V2O5 (CVO) as the anode, electrolyte, and cathode materials, respectively, show a stable cyclic performance for 600 cycles at a large current density of 3 C (1 C = 400 mA g−1), in which the capacity retention rate is 88.7%. This research provides a new strategy for promoting the application of the aqueous ZIBs with high performance and environmental benignity. [ABSTRACT FROM AUTHOR]