Dai Lizhi,Yu Tong,Wang Jingxuan,Li Youchong,Cao Zheyuan,Xiao Jianhua
2-ethylhexyl diphenyl phosphate (EHDPHP), a ubiquitous organic phosphorus flame retardant, is extensively employed in food packaging, flame retardancy applications, and other industrial processes as a crucial chemical. However, recent discoveries have underscored its diverse toxic effects, posing a severe potential threat to biological health. Skeletal muscle, vital for locomotion, relies heavily on proper differentiation during development and maintenance for strength and functionality. This study investigated the impact of EHDPHP on skeletal muscle differentiation by culturing C2C12 cells with varying concentrations of EHDPHP during induction of differentiation, as well as constructing a mouse muscle injury repair model through oral administration of 30 μg/kg EHDPHP for 7 weeks. Exposure to EHDPHP was found to impede skeletal muscle differentiation in mice. Utilizing techniques such as western blot analysis, RNA-seq, and qRT-PCR, our preliminary analysis revealed that low concentrations of EHDPHP inhibited the expression of ACTC1, subsequently suppressing MyoG and MYH2 expression levels, thereby hindering C2C12 myoblast differentiation. Furthermore, EHDPHP exposure disrupted the repair process of muscle injury in mice and compromised the integrity of the repaired tissue. In conclusion, these findings elucidate the detrimental effects of EHDPHP exposure on muscle differentiation, uncovering its muscle toxicity.
As a meat substitute, cell cultured meat aims to simulate the composition of real meat to provide nutrient substance. The myotube formation efficiency of myoblasts in vitro is the key for simulating the structure and composition of muscle tissue. Therefore, this study is aimed to explore the most effective groove widths for myoblasts fusion and related molecular mechanism. The results of immunofluorescence showed that the grooves with a width range of 50 μm–1000 μm were beneficial to cell arrangement compared to flat structure. At the same time, the expression of myogenin ( Myog ) and myosin heavy chain 2 ( Myh2 ) up-regulated. However, the cell fusion index of myoblasts was higher in grooves with a width of 100 μm, 200 μm and 300 μm. Furthermore, Cytochalasin D disrupted intracellular stress fibers and myotube formation. However, there were still many myotubes formed in the 200 μm groove with the addition of Cytochalasin D. The expression of fusion related genes was higher than the flat group. Moreover, incorporating groove structure into scaffolds of soybean protein isolate and pea protein isolate could enhance cell adhesion, activity and myogenic differentiation of myoblasts. This could provide ideas for scaffolds design of cultured meat products using groove structure.