Chinese Journal of Dermatology ›› 2022, Vol. 55 ›› Issue (1): 40-46.doi: 10.35541/cjd.20210443

• Original Articles • Previous Articles     Next Articles

Regulatory role of circIGF2BP3 in autophagy in photoaged dermal fibroblasts

Qu Yingying, Fang Jiaqi, Ouyang Mengting, Wang Mengyao, Huang Xianyin, Zheng Yue, Lai Wei, Xu Qingfang   

  1. Department of Dermatology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China
  • Received:2021-06-10 Revised:2021-11-03 Online:2022-01-15 Published:2021-12-31
  • Contact: Xu Qingfang E-mail:xqf69@163.com
  • Supported by:
    National Natural Science Foundation of China (81773340); Natural Science Foundation of Guangdong Province of China (2021A1515012622)

Abstract: 【Abstract】 Objective To preliminarily investigate the effect of circIGF2BP3 on autophagy in photoaged dermal fibroblasts. Methods Human dermal fibroblasts were isolated from circumcised foreskin tissues from 6 children in the Department of Urological Surgery, Third Affiliated Hospital of Sun Yat-sen University. An ultraviolet A (UVA)-induced photoaged human dermal fibroblast model (UVA radiation group) was established by repeated UVA radiation at a dose of 10 J/cm2 for 14 consecutive days, and human dermal fibroblasts receiving no treatment served as control group. The photoaged cell model was verified by β-galactosidase staining, Western blot analysis for determining P21 protein expression, and cell counting kit-8 (CCK8) assay for evaluating cell viability. Moreover, Western blot analysis was performed to determine the protein expression of autophagy-related proteins P62, microtubule-associated protein 1 light chain 3 (LC3)-Ⅰand LC3-Ⅱ in photoaged human dermal fibroblasts, and real-time quantitative RCR (qRT-PCR) to verify the differential expression of circIGF2BP3 between photoaged and normal human dermal fibroblasts. Furthermore, circIGF2BP3 was biologically annotated. Some cultured primary human dermal fibroblasts were divided into 4 groups: empty vector group transfected with an empty vector, UVA + empty vector group transfected with an empty vector followed by repeated UVA radiation, circIGF2BP3 group transfected with a circIGF2BP3-overexpressing lentiviral vector, UVA + circIGF2BP3 group transfected with a circIGF2BP3-overexpressing lentiviral vector followed by repeated UVA radiation. Western blot analysis was performed to determine the expression of autophagy-related proteins. Statistical analysis was carried out by using t test, one-way analysis of variance and least significant difference-t test. Results Compared with the control group, the UVA radiation group showed significantly increased proportions of β-galactosidase-positive cells (61.33% ± 5.78% vs. 6.37% ± 0.32%, t = 9.49, P < 0.01) and P21 expression(1.25 ± 0.03 vs. 1.00 ± 0.05, t = 4.26, P < 0.05), but significantly decreased cell viability (74.33% ± 3.48% vs. 100%, t = 7.38, P < 0.01). Moreover, the P62 expression and LC3-Ⅱ/Ⅰ ratio were significantly higher in the UVA radiation group than in the control group (both P < 0.05). The relative expression of circIGF2BP3 was 0.72 ± 0.04 in the photoaged human dermal fibroblasts, which was significantly lower than that in the normal human dermal fibroblasts (1.00 ± 0.03, t = 5.46, P < 0.01). The P62 expression and LC3-Ⅱ/Ⅰ ratio were significantly lower in the circIGF2BP3 group (0.60 ± 0.01, 0.71 ± 0.01, respectively) than in the empty vector group (1.00 ± 0.02, 1.00 ± 0.01, t = 16.25, 2.75, P < 0.01, < 0.05, respectively), and lower in the UVA + circIGF2BP3 group (1.05 ± 0.02, 2.04 ± 0.05, respectively) than in the UVA + empty vector group (1.31 ± 0.02, 2.72 ± 0.14, t = 10.493, 6.472, respectively, both P < 0.01). Conclusion circIGF2BP3 can regulate autophagy in UVA-induced photoaged dermal fibroblasts, which provides a new potential therapeutic target for the prevention and treatment of skin photoaging.

Key words: Skin aging, Cell aging, Autophagy, Fibroblasts, Circular RNA, circIGF2BP3