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Sesamin is a lignan compound in plants that has various pharmacological effects, including reducing diabetes-associated injuries, regulating fatty acid and cholesterol metabolism, and exerting antiinflammatory and antitumour effects. Previous studies have reported that sesamin can inhibit the proliferation of several types of tumour cells and exert antitumour effects. However, the antitumour effect of sesamin on T-cell lymphoma is still unknown. In this study, we selected a T-cell lymphoma mouse model to investigate the mechanism of sesamin against T-cell lymphoma via programmed cell death in vivo and in vitro. We found that sesamin could significantly inhibit the growth of EL4 cells in a tumour-bearing mouse model. Sesamin markedly inhibited the proliferation of EL4 cells by inducing apoptosis, pyroptosis and autophagy. Autophagy occurred earlier than apoptosis and pyroptosis in EL4 cells after sesamin treatment. Blocking autophagy inhibited apoptosis and pyroptosis in EL4 cells after sesamin treatment. Taken together, these results suggested that sesamin promoted apoptosis and pyroptosis via autophagy to enhance antitumour effects on murine T-cell lymphoma. This study expands our knowledge of the pharmacological effects of sesamin on T-cell lymphoma, and provides a theoretical basis for the development of new antitumour drugs and treatments for T-cell lymphoma.

Skeletal muscle atrophy in the aged causes loss in muscle mass and functions. Naturally occurring antioxidant flavonoid apigenin is able to ameliorate obesity- and denervation-induced muscle atrophies, but its effects on age-related muscle atrophy remain unknown. We hypothesized that apigenin can relieve muscle atrophy in aged mice, probably through special effects on reactive oxygen species and enzymes with antioxidant functions. For the male mice of the study, apigenin showed significant dose-dependent effects in relieving aging-related muscle atrophy according to results of frailty index as indicator of frailty associated with aging, grip strength, and running distance. Apigenin also improved myofiber size and morphological features and increased mitochondria number and volume, as manifested by succinate dehydrogenase staining and transmission electron microscopy. Our tests also suggested that apigenin promoted activities of enzymes such as superoxide dismutase and glutathione peroxidase for antioxidation and those for aerobic respiration such as mitochondrial respiratory enzyme complexes I, II, and IV, increased ATP, and enhanced expression of genes such as peroxisome proliferator-activated receptor-γ coactivator 1α, mitochondrial transcription factor A, nuclear respiratory factor-1, and ATP5B involved in mitochondrial biogenesis. The data also suggested that apigenin inhibited Bcl-2/adenovirus E1B 19kD-interacting protein 3 and DNA fragmentation as indicators of mitophagy and apoptosis in aged mice with skeletal muscle atrophy. Together, the results suggest that apigenin relieves age-related skeletal muscle atrophy through reducing oxidative stress and inhibiting hyperactive autophagy and apoptosis.

Curcumin has been reported to attenuate muscle atrophy. However, the underling mechanism remains unclear. The aim of this study was to investigate whether curcumin could improve chronic kidney disease (CKD)-induced muscle atrophy and mitochondrial dysfunction by inhibiting glycogen synthase kinase-3β (GSK-3β) activity. The sham and CKD mice were fed either a control diet or an identical diet containing 0.04% curcumin for 12 weeks. The C2C12 myotubes were treated with H2O2 in the presence or absence of curcumin. In addition, wild-type and muscle-specific GSK-3β knockout (KO) CKD model mice were made by 5/6 nephrectomy, and the sham was regarded as control. Curcumin could exert beneficial effects, including weight maintenance and improved muscle function, increased mitochondrial biogenesis, alleviated mitochondrial dysfunction by increasing adenosine triphosphate levels, activities of mitochondrial electron transport chain complexes and basal mitochondrial respiration and suppressing mitochondrial membrane potential. In addition, curcumin modulated redox homeostasis by increasing antioxidant activity and suppressed mitochondrial oxidative stress. Moreover, the protective effects of curcumin had been found to be mediated via inhibiting GSK-3β activity in vitro and in vivo. Importantly, GSK-3β KO contributed to improved mitochondrial function, attenuated mitochondrial oxidative damage and augmented mitochondrial biogenesis in muscle of CKD. Overall, this study suggested that curcumin alleviated CKD-induced mitochondrial oxidative damage and mitochondrial dysfunction via inhibiting GSK-3β activity in skeletal muscle.