Dose-dependent pro- or anti-scar-preventing responses of freeze-dried amniotic membrane extract in relation to suppression of connective tissue growth factor and α-smooth muscle actin

• Published in: Journal of pharmaceutical investigation Vol. 51; no. 3; pp. 327 - 336
• Main Authors: Kang, Mirin, Cho Lee, Ae-Ri
• Format: Journal Article
• Language: English
• Published: Singapore Springer Singapore 01.05.2021; 한국약제학회
• Subjects: Biomedical and Life Sciences; Biomedicine; Original Article; 약학; Connective tissue growth factor; Wound healing; Freeze-dried amniotic membrane extract; Scar; α-Smooth muscle actin
• ISSN: 2093-5552; 2093-6214
• DOI: 10.1007/s40005-021-00518-y

Purpose Dose-dependent pro- or anti-scar-preventing effects of amniotic membrane extract (AME) are unclear. This study investigated the dose-dependent effects of freeze-dried AME on connective tissue growth factor (CTGF) and α-smooth muscle action (α-SMA) (key determinants of excessive scarring) expression in an attempt to develop medication for scarless wound healing. Methods The inhibitory effect of freeze-dried AME on α-SMA was visualized through immunofluorescence confocal microscopy. The suppressive effect of 10 different concentrations of AME (0.0025–0.25 µg/mL) on CTGF and α-SMA was determined, and rates of collagen lattice contraction were measured. Results AME inhibited the trans-differentiation of fibroblasts to myofibroblasts, a hallmark of scar formation. AME downregulated CTGF and α-SMA in a dose-dependent manner; supplementation of 0.0175 µg/mL of AME in cell culture media downregulated CTGF (by 49%; p < 0.05) and α-SMA (by 33%; p < 0.05) relative to control values, the effect saturating with a subsequent increase in AME levels to 0.025 µg/mL. Collagen lattice contraction was maximally inhibited (75 ± 8%) upon treatment with 0.0175 µg/mL AME relative to the control (44 ± 6%). Conclusion AME downregulates α-SMA and inhibits the trans-differentiation of fibroblasts to myofibroblasts in a dose-dependent manner. Treatment of cells with high AME concentrations retained high α-SMA concentration levels. A delicate balance between the wound healing properties and pro-fibrotic abilities of AME should be considered for selecting an appropriate therapeutic dose.