Thyrotropin-releasing hormone and its analogs accelerate wound healing.
BACKGROUND
Thyrotropin-releasing hormone (TRH) is a classical hormone that controls thyroid hormone production in the anterior pituitary gland. However, recent evidence suggested that TRH is expressed in nonhypothalamic tissues such as epidermal keratinocytes and dermal fibroblasts, but its function is not clear. This study aimed to investigate the effects of TRH and its analogs on wound healing and explore the underlying mechanisms.


METHODS
A stented excisional wound model was established, and the wound healing among vehicle control, TRH, and TRH analog taltirelin treatment groups was evaluated by macroscopic and histologic analyses. Primary fibroblasts were isolated from rat dermis and treated with vehicle control, TRH or taltirelin, cell migration, and proliferation were examined by scratch migration assay, MTT, and 5-ethynyl-2'- deoxyuridine (EdU) assay. The expression of α-Smooth muscle actin in fibroblasts was detected by Western blot and immunocytochemical analysis.


RESULTS
TRH or taltirelin-treated wounds exhibited accelerated wound healing with enhanced granulation tissue formation and increased re-epithelialization and tissue formation. Furthermore, TRH or taltirelin promoted the migration and proliferation of fibroblasts and induced the expression of α-Smooth muscle actin in fibroblasts.


CONCLUSIONS
TRH is important in upregulating the phenotypes of dermal fibroblasts and plays a role in accelerating wound healing.
Department of Head and Neck Surgery, The Third Affiliated Hospital of Harbin Medical University, Harbin, China.
Chunlei
C
Nie
Department of Plastic Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
Daping
D
Yang
Department of Head and Neck Surgery, The Third Affiliated Hospital of Harbin Medical University, Harbin, China.
Nan
N
Liu
Department of Pharmacology, Harbin Medical University, Harbin, China.
Deli
D
Dong
Department of Cell Biology, Harbin Medical University, Harbin, China.
Jin
J
Xu
Department of Head and Neck Surgery, The Third Affiliated Hospital of Harbin Medical University, Harbin, China. Electronic address: Jiewu_zhang@126.com.
Jiewu
J
Zhang
D000199:Actins / Q000378:metabolism; D000818:Animals; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects / Q000502:physiology; D008297:Male; D010641:Phenotype; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology* / Q000502:physiology / Q000627:therapeutic use*; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology*
D000199:Actins; D013973:Thyrotropin-Releasing Hormone; C498862:Acta2 protein, rat
Dermal fibroblasts; Excisional wound healing; Taltirelin; Thyrotropin-releasing hormone; α-Smooth muscle actin