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.

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.

OBJECTIVETo analyze the effect of small interfering RNA (siRNA) targeting mouse epididymis-specific colipase-like (meClps) gene on mouse sperm mobility.

METHODSThe eukaryotic expression vector pDsRed2.0-C1-meClps was constructed and transfected into NIH-3T3 cells, and the protein expression was detected with anti-meClps serum. Three interfering sequences targeting meClps (RNAi-251, 224 and 286) were inserted into lentiviral vectors pRNAT-U6.2/lenti, which were co-transfected with pDsRed2.0-C1-meClps into NIH-3T3 cells. The RNA interfering efficiency was confirmed by semi-quantitative PCR and Western blotting. The lentivirus, packed with the lentiviral vector with the highest interfering efficiency, was injected into the caput tissues of mouse epididymis, and its effect on sperm mobility of the cauda epididymis was evaluated.

RESULTSAll the 3 lentiviral RNAi vectors targeting meClps could inhibit the mRNA and protein expressions of meClps, among which pRNAT-U6.2/lenti-RNAi-251 had the highest interfering efficiency. The lentivirus packed with pRNAT-U6.2/lenti-RNAi-251 significantly reduced the path velocity of cauda sperm after injection into the caput epididymis of the mice (P<0.05).

CONCLUSIONKnock-down meClps expression by lentiviral-mediated RNA interference can lower sperm mobility of mice.

Animals ; Epididymis ; Gene Targeting ; Genetic Vectors ; Lentivirus ; Male ; Mice ; NIH 3T3 Cells ; RNA Interference ; RNA, Messenger ; RNA, Small Interfering ; Sperm Motility ; Spermatozoa ; Transfection