Abstract：
Inspired by glycyrrhizin\'s strong pharmacological activities and the directed self-assembly into hydrogels, we created a novel carrier-free, injectable hydrogel (CAR@glycygel) by combining glycyrrhizin with carvacrol (CAR), without any other chemical crosslinkers, to promote wound healing on bacteria-infected skin. CAR appeared to readily dissolve and load into CAR@glycygel. CAR@glycygel had a dense, porous, sponge structure and strong antioxidant characteristics. In vitro, it showed better antibacterial ability than free CAR. For methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, and Escherichia coli, the diameter of inhibition zone values of CAR@glycygel were 3.80 ± 0.04, 3.31 ± 0.20 and 3.12 ± 0.24 times greater, respectively, than those of free CAR. The MICs for CAR@glycygel was 156.25 μg/mL while it was 1250.00 μg/mL for free CAR to these three bacteria. Its antibacterial mechanism appeared to involve destruction of the integrity of the bacterial cell wall and biomembrane, leading to a leakage of AKP and inhibition of biofilm formation. In vivo, CAR@glycygel effectively stopped bleeding. When applied to skin wounds on rats infected with MRSA, CAR@glycygel had strong bactericidal activity and improved wound healing. The wound healing rates for CAR@glycygel were 49.59 ± 15.78 %, 93.02 ± 3.09 % and 99.02 ± 0.55 % on day 3, day 7, and day 11, respectively, which were much better than blank control and positive control groups. Mechanisms of CAR@glycygel accelerating wound healing involved facilitating epidermis remolding, promoting the growth of hair follicles, stimulating collagen deposition, mitigating inflammation, and promoting angiogenesis. Overall, CAR@glycygel showed great potential as wound dressing for infected skin wounds.
摘要：
受甘草甜素强大的药理活性和定向自组装成水凝胶的启发，我们创造了一个新的无载体，通过将甘草甜素与香芹酚（CAR）结合使用的可注射水凝胶（CAR@glycygel），没有任何其他化学交联剂，促进细菌感染皮肤的伤口愈合。CAR似乎容易溶解并负载到CAR@glycygel中。CAR@glycygel有一个致密的，多孔，海绵结构和强抗氧化特性。体外，它显示出比游离CAR更好的抗菌能力。对于耐甲氧西林金黄色葡萄球菌（MRSA），金黄色葡萄球菌,和大肠杆菌，CAR@glycygel的抑制区直径值分别为3.80±0.04、3.31±0.20和3.12±0.24倍，分别,比那些免费的车。CAR@glycygel的MIC为156.25μg/mL,而游离CAR对这三种细菌的MIC为1250.00μg/mL。其抗菌机制似乎涉及破坏细菌细胞壁和生物膜的完整性，导致AKP的泄漏和生物膜形成的抑制。在体内,CAR@glycygel有效止血。当应用于感染MRSA的大鼠的皮肤伤口时，CAR@glycygel具有较强的杀菌活性并改善伤口愈合。CAR@glycygel的伤口愈合率为49.59±15.78%，第3天、第7天和第11天分别为93.02±3.09%和99.02±0.55%,明显优于空白对照组和阳性对照组。CAR@glycygel加速伤口愈合的机制涉及促进表皮重塑，促进毛囊的生长，刺激胶原蛋白沉积，缓解炎症，促进血管生成。总的来说,CAR@glycygel显示出作为感染皮肤伤口的伤口敷料的巨大潜力。
