Biomaterials Division, Central Leather Research Institute, Chennai, India.
J Pharm Pharmacol. 2009 Dec;61(12):1617-23. doi: 10.1211/jpp/61.12.0005.
A novel collagen-based dressing consisting of 2,3-dihydroxybenzoic-acid-modified gelatin microspheres loaded with doxycycline has previously been reported to address both infection and matrix degradation. In the present study the potential benefits of the dressing were investigated in an excisional wound model in rats challenged with Pseudomonas aeruginosa.
A full-thick excisional wound (1.5 x 1.5 cm) was created on the dorsum of the rats and infection induced by injecting 10(5) colony-forming units (CFU) of P. aeruginosa. The healing pattern was assessed from wound reduction, matrix metalloprotease (MMP) levels, CFU reduction and histological and biochemical analysis.
The treated group exhibited complete healing by day 15, compared with day 24 in the control group. Early subsidence of infection (99.9% by day 9) resulted in faster epidermal resurfacing and fibroplasias, whereas the microbial load exceeded 10(3) CFU even on day 15 in the control group and caused severe inflammation. Biochemical analysis showed that the expression of both collagen and hexosamine was significantly increased in the treated group. Gelatin zymography revealed prolonged expression of MMPs 2, 8 and 9 in the control group compared with the treated group.
The study indicates that the developed dressing attenuated both infection and metalloprotease levels, and may therefore have potential application in wound healing.
先前有报道称，一种由载有多西环素的 2,3-二羟基苯甲酸修饰明胶微球组成的新型胶原基敷料可同时解决感染和基质降解问题。在本研究中，我们在经绿脓假单胞菌感染的大鼠切创模型中研究了该敷料的潜在益处。
在大鼠背部制作全层切创（1.5×1.5 cm），并通过注射 10（5）个菌落形成单位（CFU）的绿脓假单胞菌来诱导感染。通过评估伤口缩小、基质金属蛋白酶（MMP）水平、CFU 减少以及组织学和生物化学分析来评估愈合模式。
与对照组相比，治疗组在第 15 天完全愈合，而对照组在第 24 天愈合。早期感染消退（第 9 天达到 99.9%）导致更快的表皮再形成和纤维形成，而对照组的微生物负荷甚至在第 15 天仍超过 10（3）CFU，并导致严重炎症。生化分析表明，治疗组的胶原蛋白和己糖胺表达均显著增加。明胶酶谱分析显示，与治疗组相比，对照组 MMPs 2、8 和 9 的表达时间延长。
该研究表明，所开发的敷料可减轻感染和金属蛋白酶水平，因此可能在伤口愈合中有应用潜力。
