The animal experimental process was approved by the Center for Food and Drug Safety Evaluation, Hubei Center for Disease Control and Prevention, Hubei Academy of Preventive Medicine. The animal experiment ethics approval number was 202110166. All animals were maintained and used in accordance with the Animal Management Rules of the Ministry of Health of the People’s Republic of China and the Guide for the Care and Use of Laboratory Animals—Chinese Version. In addition, all animal experiments were conducted with the assistance of the Wuhan Pinuofei Biological Technology Co. Ltd.
Hemolysis assay test was conducted before the in vivo experiment. Fresh RBCs (4 ml) were separated by centrifuge at 3000 rpm for 10 min at 4°C, washed with saline for three times, and diluted to final concentration [5% (v/v)]. Different samples were separately added to 500 μl of RBCs and incubated at 37°C for 4 hours. At the end of incubation, the solution was centrifuged at 3000 rpm for 10 min at 4°C, and the hemolytic activity was determined at 570 nm with a microplate reader: Rate of hemolysis (%) = [(ODsample − ODnegative)/(ODpositive − ODnegative)] × 100%.
The mice (Balb/c, female, 8 to 10 weeks, and 25 to 30 g) were weighed and anesthetized with the anesthetic isoflurane, the hair on the back of the mice was removed in a sterile biosafety cabinet using a shaving machine and a hair removal cream, and 100 μl of P. acnes (2 × 105 CFUs/ml) was intradermally injected into the skin of the back of the mice after disinfection of the skin with 75% alcohol cotton balls to establish an animal model of common acne. There were five mice per group. The mice were treated with different materials for 7 days. MNs were pressed into the skin by hand against the acne site and held for 3 min. The blank control group, medical acne ointment, patch, blank MN patch, MN patch, and MN patch were treated for 10 min with ultrasound (medical ultrasound probe, 1 cm in diameter). During the treatment period, the swelling volume of acne was measured daily with microcalipers. The changes in the acne on the back of mice were photographed and recorded at 1, 3, and 7 days after the experiment, and after euthanasia treatment, and the skin was cut along 2 mm of the wound edge to complete the tissue acquisition. The expression of factors related to wounds, underlying muscle repair, and inflammatory indexes were analyzed. For skin tissue acquisition and embedding tissue fixation, tissue fixation, tissue dehydration, tissue permeabilization, tissue wax immersion, tissue embedding, tissue sectioning were performed.
Hemolysis assay test was conducted before the in vivo experiment. Fresh RBCs (4 ml) were separated by centrifuge at 3000 rpm for 10 min at 4°C, washed with saline for three times, and diluted to final concentration [5% (v/v)]. Different samples were separately added to 500 μl of RBCs and incubated at 37°C for 4 hours. At the end of incubation, the solution was centrifuged at 3000 rpm for 10 min at 4°C, and the hemolytic activity was determined at 570 nm with a microplate reader: Rate of hemolysis (%) = [(ODsample − ODnegative)/(ODpositive − ODnegative)] × 100%.
The mice (Balb/c, female, 8 to 10 weeks, and 25 to 30 g) were weighed and anesthetized with the anesthetic isoflurane, the hair on the back of the mice was removed in a sterile biosafety cabinet using a shaving machine and a hair removal cream, and 100 μl of P. acnes (2 × 105 CFUs/ml) was intradermally injected into the skin of the back of the mice after disinfection of the skin with 75% alcohol cotton balls to establish an animal model of common acne. There were five mice per group. The mice were treated with different materials for 7 days. MNs were pressed into the skin by hand against the acne site and held for 3 min. The blank control group, medical acne ointment, patch, blank MN patch, MN patch, and MN patch were treated for 10 min with ultrasound (medical ultrasound probe, 1 cm in diameter). During the treatment period, the swelling volume of acne was measured daily with microcalipers. The changes in the acne on the back of mice were photographed and recorded at 1, 3, and 7 days after the experiment, and after euthanasia treatment, and the skin was cut along 2 mm of the wound edge to complete the tissue acquisition. The expression of factors related to wounds, underlying muscle repair, and inflammatory indexes were analyzed. For skin tissue acquisition and embedding tissue fixation, tissue fixation, tissue dehydration, tissue permeabilization, tissue wax immersion, tissue embedding, tissue sectioning were performed.
