The combination of quercetin and leucine synergistically improves grip strength by attenuating muscle atrophy by multiple mechanisms in mice exposed to cisplatin.

Both quercetin and leucine have been shown to exert moderately beneficial effects in preventing muscle atrophy induced by cancers or chemotherapy. However, the combined effects of quercetin and leucine, as well as the possible underlying mechanisms against cisplatin (CDDP)-induced muscle atrophy and cancer-related fatigue (CRF) remain unclear. To investigate the issues, male BALB/c mice were randomly assigned to the following groups for 9 weeks: Control, CDDP (3 mg/kg/week), CDDP+Q (quercetin 200 mg/kg/day administrated by gavage), CDDP+LL (a diet containing 0.8% leucine), CDDP+Q+LL, CDDP+HL (a diet containing 1.6% leucine), and CDDP+Q+HL. The results showed that quercetin in combination with LL or HL synergistically or additively attenuated CDDP-induced decreases in maximum grip strength, fat and muscle mass, muscle fiber size and MyHC level in muscle tissues. However, the combined effects on locomotor activity were less than additive. The combined treatments decreased the activation of the Akt/FoxO1/atrogin-1/MuRF1 signaling pathway (associated with muscle protein degradation), increased the activation of the mTOR and E2F-1 signaling pathways (associated with muscle protein synthesis and cell cycle/growth, respectively). The combined effects on signaling molecules present in muscle tissues were only additive or less. In addition, only Q+HL significantly increased glycogen levels compared to the CDDP group, while the combined treatments considerably decreased CDDP-induced proinflammatory cytokine and MCP-1 levels in the triceps muscle. Using tumor-bearing mice, we demonstrated that the combined treatments did not decrease the anticancer effect of CDDP. In conclusion, this study suggests that the combination of quercetin and leucine enhanced the suppressed effects on CDDP-induced muscle weakness and CRF through downregulating muscle atrophy and upregulating the glycogen level in muscle tissues without compromising the anticancer effect of CDDP. Multiple mechanisms, including regulation of several signaling pathways and decrease in proinflammatory mediator levels in muscles may contributed to the enhanced protective effect of the combined treatments on muscle atrophy.

Applications of Cellulose Nanomaterials in Stimuli-Responsive Optics.

As one of the most abundant biopolymers, cellulose has been a basic but essential building block of human society, with its use dating back thousands of years. With recent developments in nanotechnology and increasing environmental concerns, cellulose-based nanomaterials are now gaining attention as promising green material candidates for many high-value applications as a result of their biocompatibility and advantageous physical and chemical properties. In particular, cellulose nanocrystals are notable for their optical properties that can respond to various environmental stimuli as a result of the unique chiral nematic structure of the material. Compositing cellulosic materials with functional polymers, small molecules, and other nanomaterials can further stabilize and amplify these responsive optical signals and introduce multiple new functionalities. On the basis of these capabilities, many advanced applications of cellulose nanomaterials have been proposed, including chemical sensors, photonic papers, decorative coatings, data security, and smart textiles. In this review, we discuss and summarize recent advances in this emerging field of stimuli-responsive optics based on cellulose nanomaterials.