Tetrahedral Framework Nucleic Acids Inhibit Muscular Mitochondria-Mediated Apoptosis and Ameliorate Muscle Atrophy in Sarcopenia.

Sarcopenia is known as age-related muscle atrophy, which influences over a quarter of the elderly population worldwide. It is characterized by a progressive decline in muscle mass, strength, and performance. To date, clinical treatments in sarcopenia are limited to rehabilitative interventions and dietary supplements. Tetrahedral framework nucleic acids (tFNAs) represent a novel kind of DNA-based nanomaterial with superior antiapoptosis capacity in cells, tissues, organs, and systems. In our study, the therapeutic effect of tFNAs treatment on sarcopenia was evaluated both in vivo and in vitro. Results from muscular biophysiological characteristics demonstrated significant improvement in muscle function and endurance in the aged mouse model, and histologic examinations also showed beneficial morphological changes in muscle fibers. In vitro, DEX-induced sarcopenic myotube atrophy was also ameliorated through the inhibition of mitochondria-mediated cell apoptosis. Collectively, tFNAs treatment might serve as an alternative option to deal with sarcopenia in the near future.

Controlled bacteriostasis of tea polyphenol loaded ultrahigh molecular weight polyethylene with high crosslink density and oxidation resistance for total joint replacement.

To avoid catastrophic bacterial infection in prosthesis failure, ultrahigh molecular weight polyethylene (UHMWPE), a common bearing material of artificial joints, has been formulated with antibiotics to eliminate bacteria locally at the implant site. However, the pressing issues regarding cytotoxic effects and evolution of drug resistant bacteria necessitates the development of bio-friendly bacteriostat with long bacteriostatic efficacy. Herein, tea polyphenol extracted from nature source was introduced in UHMWPE as a biogenic antimicrobial. Controlled antimicrobial activity was achieved by chemical crosslinking to regulate the release of the tea polyphenol. In addition, the crosslinking efficiency of UHMWPE blends with high loaded tea polyphenol was significantly improved in comparison to radiation crosslinking. The immobilized tea polyphenols also enhanced the oxidation stability of the UHMWPE, which is essential to prolong the service life in vivo and the storage time in vitro. The blends presented good biocompatibility, despite cell repellent on the highly crosslinked surface. Chemically crosslinked tea polyphenol/UHMWPE exhibited feasible properties for total joint implants, which is promising for clinical application.