Quantitative proteomics analysis of differentially expressed proteins in patients with sarco-osteoporosis and osteoporosis

Abstract

Objective The differential expression of protein mass spectrum of patients with sarco-osteoporosis (SO) and osteoporosis (OP) was constructed to reveal the molecular mechanism of sarcopenia that facilitates the development of osteoporosis. Methods The samples of muscle tissues of patients with sarco-osteoporosis and osteoporosis were collected, and label free quantitative proteomic technique was used to analyze and identify the differentially expressed proteins between the two groups, and differential expressed proteins were analyzed by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG). Results There were 1 507 differentially expressed proteins identified. Among them, 53 were significantly dysregulated, including 47 down-regulated proteins and 6 up-regulated ones. The GO analysis showed that differentially expressed proteins in SO group were mainly involved in the redox process, protein hydrolysis and metabolic process, and the main molecular functions were protein binding, adenosine triphosphate (ATP) binding and calcium binding. The most significant cellular structural difference between the SO and OP groups was total components located in the membrane. Based on KEGG pathway analysis, connexin 43 (Cx43), voltage dependent L-type calcium channel (VLCC), superoxide dismutase (SOD) were screened as candidate proteins which may be involved in the mechanism of bone remodeling of osteoporosis. Conclusion Cx43, VLCC, SOD may be associated with bone loss in patients with sarcopenia. Key words: Sarco-osteoporosis; Osteoporosis; Label-free quantitative proteomics; Bioinformatics analysis