Cutibacterium acnes promotes inflammation in acne by inducing Gasdermin E-mediated pyroptosis in keratinocytes
- VernacularTitle:痤疮丙酸杆菌通过诱导角质形成细胞发生Gasdermin E介导的焦亡促进痤疮炎症反应
- Author:
Fengyuan ZHANG
1
;
Sihan CHEN
;
Zizhen ZHOU
;
Meng ZHOU
;
Rong ZENG
;
Xu CHEN
;
Ni LIAN
;
Min LI
Author Information
- Publication Type:Journal Article
- Keywords: Acne vulgaris; Propionibacterium acnes; Pyroptosis; HaCaT cells; GSDME; Interleukin-1beta; Tumor necrosis factor-alpha; Retionl
- From: Chinese Journal of Dermatology 2025;58(7):623-629
- CountryChina
- Language:Chinese
- Abstract: Objective:To investigate the role of Gasdermin E (GSDME) -mediated keratinocyte pyroptosis induced by Cutibacterium acnes ( C.acnes) in the pathogenesis of acne. Methods:The human immortalized keratinocyte HaCaT cells were stimulated with heat-inactived C.acnes for 15 minutes to 24 hours, and Western blot analysis was performed to determine the expression of cleaved GSDME (GSDME-NT) in HaCaT cells at different time points. Skin tissue samples were collected from 5 acne patients and 4 healthy controls, who visited the Hospital for Skin Diseases, Chinese Academy of Medical Sciences from January 2 to December 1, 2024; additionally, 3 samples of acne cyst contents and 3 samples of normal follicle contents were collected. Immunohistochemical study and Western blot analysis were conducted to determine GSDME-NT expression in the epidermis. Enzyme-linked immunosorbent assay (ELISA) was performed to detect levels of interleukin (IL) -1β and tumor necrosis factor (TNF) -α in acne cyst or normal follicle contents. GSDME-knockdown HaCaT cells were constructed by transfection with lentivirus carrying GSDME-shRNA, and HaCaT cells transfected with lentivirus carrying the nonsense sequence control (NC) served as controls; ELISA was performed to detect the levels of IL-1β and TNF-α in GSDME-knockdown HaCaT cells after C. acnes stimulation ( C. acnes + GSDME knockdown group) , as well as in the phosphate-buffered saline (PBS) + NC group, C. acnes + NC group, and PBS + GSDME knockdown group. Western blot analysis was conducted to determine the GSDME-NT expression in HaCaT cells pretreated with or without retinol after C. acnes stimulation. Results:The cleavage of GSDME in HaCaT cells began at 1 hour after in vitro C. acnes stimulation, and GSDME-NT could be detected at this time. Compared with the control epidermis, the proportion of GSDME-NT-positive HaCaT cells (9.34% ± 2.92% vs. 3.05% ± 1.14%, t = -3.47, P = 0.026) and GSDME-NT protein expression levels ( t = -3.51, P = 0.025) significantly increased in the lesional epidermis of acne patients. The levels of IL-1β and TNF-α were significantly higher in the acne cyst contents than in the normal follicle contents (IL-1β: 1 337.24 [1 182.32, 2 230.61] pg/ml vs. 0.00 [0.00, 108.21] pg/ml, Z = 1.99, P = 0.046; TNF-α: 811.31 [438.26, 817.73] pg/ml vs. 46.67 [12.41, 53.21] pg/ml, Z = 1.96, P = 0.049) . ELISA showed that the levels of IL-1β and TNF-α were significantly higher in the C. acnes + NC group (12.12 ± 3.07 pg/ml, 26.06 ± 1.57 pg/ml, respectively) than in the PBS + NC group (3.73 ± 2.24 pg/ml, 10.14 ± 0.79 pg/ml, P = 0.003, < 0.001, respectively) ; compared with the C. acnes + NC group, the levels of IL-1β and TNF-α significantly decreased in the C. acnes + GSDME knockdown group (3.38 ± 0.93 pg/ml, 12.67 ± 2.10 pg/ml, P = 0.003, < 0.001, respectively) . The GSDME-NT expression was significantly lower in the retinol + C. acnes group than in the C. acnes group ( P = 0.029) . Conclusion:C. acnes may induce GSDME-mediated pyroptosis in keratinocytes, thereby promoting the release of inflammatory factors and aggravating the inflammatory response in acne, while retinol may be able to inhibit this process.
