Plumbagin alleviates muscle atrophy in female mice through inhibiting the DANCR/NF-κB axis

Muscle atrophy is a condition of the skeletal muscular system closely related to inflammation and significantly affects a person's quality of life and physical activity. It is characterized primarily by the progressive loss of muscle mass, strength, and function. Plumbagin (PB), the main bioactive component of the traditional Chinese medicine Plumbago zeylanica L., has bFeen shown to treat various inflammatory diseases, such as osteoporosis, osteoarthritis, and sepsis. Furthermore, many biological processes, including inflammation, involve differentiation antagonistic nonprotein-coding RNA (DANCR). However, their role and clinical importance in myogenesis and amyotrophy are not well understood.

This study aimed to explore the role of DANCR and the inflammatory response in the anti-muscle atrophy effects of PB.

The expression of DANCR in muscle atrophic mice and during myogenic differentiation was examined using quantitative reverse transcription PCR (RT‒qPCR). The mechanism of DANCR in muscle atrophy was confirmed through gene knockdown, RNA sequencing (RNA-seq), RNA pull-down, RNA immunoprecipitation (RIP), immunofluorescence (IF), and luciferase reporter gene assays. Bioinformatics was utilized to investigate the mechanism by which PB treatment affects muscle atrophy. The relationship between PB and DANCR was verified by surface plasmon resonance (SPR) and RT‒qPCR. Additionally, the role of PB in muscle atrophy was explored through its control of DANCR-mediated regulation of the NF-κB pathway. Finally, the effect of PB on the myogenic differentiation of human skeletal muscle cells (HsKMCs) was investigated.

DANCR expression was upregulated in the muscle tissues of mice with muscle atrophy and downregulated during myogenic differentiation. Knockout of DANCR promoted myogenic differentiation and significantly alleviated the loss of muscle mass, strength, and function in mice with muscle atrophy. The primary mechanism involved DANCR directly binding to the p65 protein to regulate NF-κB pathway activity. Experiments revealed that PB could target the degradation of DANCR, reduce the nuclear entry of p65, and inhibit the activation of the NF-κB pathway. Consequently, PB significantly inhibited myotube atrophy and the inflammatory response in HsKMCs and promoted their myogenic differentiation by regulating the NF-κB pathway.

Our results suggest that PB regulates myogenesis and prevents amyotrophy by targeting the degradation of DANCR and inhibiting the activation of the NF-κB pathway. This study reveals the crucial role of DANCR in maintaining muscle physiology during muscle atrophy and identifies PB as an effective drug that can target DANCR degradation to alleviate muscle atrophy.