The 1st Department of Oral and Maxillofacial Surgery, Graduate School of Dentistry, Osaka University, 1-8 Yamada-oka, Suita, Osaka, 565-0871, Japan.
Department of Molecular Pathology, Division of Health Sciences, Graduate School of Medicine, Osaka University, 1-7 Yamada-oka, Suita, Osaka, 565-0871, Japan; Department of Health Economics and Management, Graduate School of Medicine, Osaka University, 1-7 Yamada-oka, Suita, Osaka, 565-0871, Japan; Department of Pediatric Dentistry, Osaka Dental University, 1-5-17 Ohtemae Chuo-ku, Osaka, 540-0008, Japan.
Peptides. 2019 Jun;116:8-15. doi: 10.1016/j.peptides.2019.04.013. Epub 2019 Apr 17.
Oral and maxillofacial skeletal muscles are critical for oral motor functions, and severe damage to these muscles by trauma or surgery may lead to persistent functional impairment. This study investigated the effects of SVVYGLR (SV) peptide, a thrombin-cleaved osteopontin-derived motif, on histopathological wound healing and functional repair after severe injury of skeletal muscles. A rat model of volumetric muscle loss bilateral masseter muscle was developed. A single dose of SV-peptide or phosphate-buffered saline (PBS) was separately injected into the injured muscle belly. Histopathological and functional analyses were performed 1-8 weeks after the treatment. Behavioral analysis during free-feeding revealed that the feeding rate markedly increased in the SV-peptide group, in contrast, the PBS group showed fewer changes after the injury. Electromyogram recordings from injured muscles demonstrated amplification of rectified burst activity over time accompanied by increased maximal amplitude and duration in the SV-peptide group, in contrast, the PBS group showed moderate changes. A lissajous figure for bilateral masseter muscle activities also revealed superior functional recovery by the SV-peptide treatment. The SV-peptide also facilitated regeneration of muscles composed of matured myofibers with a greater diameter compared to the PBS group. In addition, granulation in the earlier period and fibrosis in the later period of wound healing were significantly inhibited by the SV-peptide treatment but not by the PBS treatment. Therefore, local application of the SV-peptide could help facilitate regeneration of muscles, inhibition of fibrosis, and improvement of functional impairment of oral and maxillofacial skeletal muscles damaged by severe trauma or surgery.
口腔颌面骨骼肌对于口腔运动功能至关重要，创伤或手术导致这些肌肉严重损伤可能导致持续的功能障碍。本研究探讨了 SVVYGLR（SV）肽，一种凝血酶切割骨桥蛋白衍生的基序，对严重骨骼肌损伤后组织病理学伤口愈合和功能修复的影响。建立了双侧咬肌容积性肌肉损失的大鼠模型。将 SV-肽或磷酸盐缓冲盐水（PBS）单次注射到损伤的肌肉腹部。在治疗后 1-8 周进行组织病理学和功能分析。自由进食期间的行为分析表明，SV-肽组的进食率显著增加，而 PBS 组在损伤后变化较少。受损肌肉的肌电图记录显示，随着时间的推移，整流爆发活动的幅度逐渐增大，同时 SV-肽组的最大幅度和持续时间也增加，而 PBS 组的变化适中。双侧咬肌活动的 Lissajous 图也显示 SV-肽治疗的功能恢复更好。与 PBS 组相比，SV-肽还促进了成熟肌纤维组成的肌肉再生，其直径更大。此外，SV-肽治疗显著抑制了肉芽组织在早期和纤维化在晚期的形成，而 PBS 治疗则没有抑制作用。因此，局部应用 SV-肽有助于促进严重创伤或手术损伤的口腔颌面骨骼肌的再生、抑制纤维化和改善功能障碍。
