Insect Peptide CopA3 Mitigates the Effects of Heat Stress on Porcine Muscle Satellite Cells

Simple Summary In this study, our objective was to assess the efficacy of incorporating insect peptide CopA3 to stabilize the proliferation and heat shock protein (HSP) expression under varying temperatures (37, 39, and 41 degrees C) of porcine muscle satellite cells (PMSCs). We observed that treatment with CopA3 mitigated the deleterious impact of heat stress on cell viability. Furthermore, CopA3 exhibited a reduction in PMSCs apoptosis, while stabilizing the expression of Bcl-2-associated X (BAX), HSP70, and HSP40. These results suggest the potential of CopA3 as a heat-stress alleviator.Abstract Heat stress inhibits cell proliferation as well as animal production. Here, we aimed to demonstrate that 9-mer disulfide dimer peptide (CopA3) supplementation stabilizes porcine muscle satellite cell (PMSC) proliferation and heat shock protein (HSP) expression at different temperatures. Therefore, we investigated the beneficial effects of CopA3 on PMSCs at three different temperatures (37, 39, and 41 degrees C). Based on temperature and CopA3 treatment, PMSCs were divided into six different groups including treatment and control groups for each temperature. Cell viability was highest with 10 mu g/mL CopA3 and decreased as the concentration increased in a dose-dependent manner. CopA3 significantly increased the cell viability at all temperatures at 24 and 48 h. It significantly decreased apoptosis compared to that in the untreated groups. In addition, it decreased the apoptosis-related protein, Bcl-2-associated X (BAX), expression at 41 degrees C. Notably, temperature and CopA3 had no effects on the apoptosis-related protein, caspase 3. Expression levels of HSP40, HSP70, and HSP90 were significantly upregulated, whereas those of HSP47 and HSP60 were not affected by temperature changes. Except HSP90, CopA3 did not cause temperature-dependent changes in protein expression. Therefore, CopA3 promotes cell proliferation, inhibits apoptosis, and maintains stable HSP expression, thereby enhancing the heat-stress-tolerance capacity of PMSCs.