Matrix metalloproteinases and acute aortic dissection: Et Tu, Brute?
INTERACTIVE CARDIOVASCULAR AND THORACIC SURGERY
Authors: Takagi, Hisato; Hari, Yosuke; Nakashima, Kouki; Kuno, Toshiki; Ando, Tomo
Abstract
OBJECTIVES: To summarize the present evidence for the association of matrix metalloproteinases (MMPs) with acute aortic dissection (AAD), we performed the first meta-analysis of all currently available case-control studies comparing circulating MMP levels between AAD patients and control subjects. METHODS: To identify all studies investigating the levels of circulating MMPs in AAD patients, PubMed and Web of Science were searched up to July 2019. The levels of MMPs in AAD patients and control subjects were extracted from each study, and the standardized mean differences (SMDs) in MMP levels were generated. The study-specific estimates were combined in the random-effects model. RESULTS: Twelve studies enrolling a total of 458 AAD patients and 711 control subjects were identified and included. Pooled analyses demonstrated no significant differences in MMP-1 (4 studies; P = 0.21), MMP-2 (5 studies; P = 0.62) and MMP-3 levels (2 studies; P = 0.94) between AAD patients and control subjects; and significantly higher MMP-8 (2 studies; SMD 2.11; P = 0.020), MMP-9 (9 studies; SMD 1.54; P < 0.001) and MMP-12 levels (2 studies; SMD 1.33; P < 0.001) in AAD patients than in control subjects. CONCLUSION: High circulating MMP-9 levels are associated with AAD, and MMP-8 and MMP-12 levels may be related to AAD.
Modulating cationicity of chitosan hydrogel to prevent hypertrophic scar formation during wound healing
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
Authors: Zhang, Nihui; Gao, Tao; Wang, Yao; Liu, Juan; Zhang, Junwei; Yao, Ruijuan; Wu, Fang
Abstract
It is of great clinical significance to design wound dressing materials with combined excellent wound healing properties and superior capability to suppress hypertrophic scar formation. This study aimed to examine if and how the cationicity of chitosan would affect the hypertrophic scar-related outcomes, through preparing carboxymethyl chitosan hydrogels with different genipin concentrations (2.5%, 5%, 10% and 15%, respectively). An optimum window of chitosan cationicity (5% in our case) demonstrated potential to mitigate hypertrophic scar in wound healing by suppressing the expression of a-smooth muscle actin (a-SMA) and promoting secretion of type I matrix metalloproteinases (MMP-1). In vivo, the CMCS-5% hydrogel again showed smaller, thinner and smoother wound appearance. Moreover, the CMCS-5% sample with additional incorporation of 2% (V/V) Aloe vera gel exhibited further improved performance in scar inhibition. Overall, such findings might have important implications in chitosan-based wound dressing design for high-quality wound repair and effective scar inhibition. (C) 2020 Elsevier B.V. All rights reserved.