Role and dynamics of matrix metalloproteinase 9 and tissue inhibitor of metalloproteinase 1 in burn patients

Tissue Inhibitors of Metalloproteinase 1 (TIMP-1) and 3 (TIMP-3) as New Markers of Acute Kidney Injury After Massive Burns

BACKGROUND Acute kidney injury (AKI) is a common and serious complication after massive burn injury. One of the postulated etiologies is destruction of the extracellular matrix of nephrons, caused by a local imbalance between matrix metalloproteinases (MMPs) and specific inhibitors. The aim of this study was to analyze the dynamics of tissue inhibitors of metalloproteinases (TIMPs) during the first 5 days after massive thermal injury and the relationship with the risk of AKI. MATERIAL AND METHODS Thirty-three adults (22 men, 11 women) with severe burns were enrolled in the study. The values of TIMPs 1 to 4 were measured in blood serum and urine using the multiplex Luminex system. The associations between TIMPs and the risk of AKI were analyzed by using the generalized linear mixed models for repeated measurements. RESULTS Significant changes in serum and urine activities of TIMPs were confirmed, especially during the first 2 days after burn injury. Almost half of patients presented renal problems during the study. Significant differences between values of TIMPs in AKI and non-AKI status were also observed. However, a significant relationship between concentration of TIMPs and risk of AKI was confirmed only for urine TIMP-1 and serum TIMP-3. CONCLUSIONS The evaluation of TIMPs in the early stage after burn injury has potential benefits. The important roles of urine TIMP-1 and serum TIMP-3, as novel markers of the risk of AKI development, were confirmed. Other parameters require further analysis.

Identification and Verification of Five Potential Biomarkers Related to Skin and Thermal Injury Using Weighted Gene Co-Expression Network Analysis

Background: Burn injury is a life-threatening disease that does not have ideal biomarkers. Therefore, this study first applied weighted gene co-expression network analysis (WGCNA) and differentially expressed gene (DEG) screening methods to identify pivotal genes and diagnostic biomarkers associated with the skin burn process.

Methods: After obtaining transcriptomic datasets of burn patient skin and normal skin from Gene Expression Omnibus (GEO) and performing differential analysis and functional enrichment, WGCNA was used to identify hub gene modules associated with burn skin processes in the burn patient peripheral blood sample dataset and determine the correlation between modules and clinical features. Enrichment analysis was performed to identify the functions and pathways of key module genes. Differential analysis, WGCNA, protein-protein interaction analysis, and enrichment analysis were utilized to screen for hub genes. Hub genes were validated in two other GEO datasets, tested by immunohistochemistry for hub gene expression in burn patients, and receiver operating characteristic curve analysis was performed. Finally, we constructed the specific drug activity, transcription factors, and microRNA regulatory network of the five hub genes.

Results: A total of 1,373 DEGs in GSE8056 were obtained, and the top 5 upregulated genes were S100A12, CXCL8, CXCL5, MMP3, and MMP1, whereas the top 5 downregulated genes were SCGB1D2, SCGB2A2, DCD, TSPAN8, and KRT25. DEGs were significantly enriched in the immunity, epidermal development, and skin development processes. In WGCNA, the yellow module was identified as the most closely associated module with tissue damage during the burn process, and the five hub genes (ANXA3, MCEMP1, MMP9, S100A12, and TCN1) were identified as the key genes for burn injury status, which consistently showed high expression in burn patient blood samples in the GSE37069 and GSE13902 datasets. Furthermore, we verified using immunohistochemistry that these five novel hub genes were also significantly elevated in burn patient skin. In addition, MCEMP1, MMP9, and S100A12 showed perfect diagnostic performance in the receiver operating characteristic analysis.

Conclusion: In conclusion, we analyzed the changes in genetic processes in the skin during burns and used them to identify five potential novel diagnostic markers in blood samples from burn patients, which are important for burn patient diagnosis. In particular, MCEMP1, MMP9, and S100A12 are three key blood biomarkers that can be used to identify skin damage in burn patients.

Effect of Combining Immersion Therapy with Shengji Ointment on Wound Healing Rate and Adverse Reaction Rate in Patients with Second-Degree Burn

Objective

To explore the effect of combining immersion therapy with Shengji ointment on wound healing rate and adverse reaction rate (ARR) in patients with second-degree burn.

Methods

The data of 80 patients with second-degree burn treated in our hospital from February 2019 to February 2020 were retrospectively analyzed by the means of retrospective study, and the patients were equally divided into the treatment group and the control group according to their admission order, with 40 cases each. Immersion therapy was performed to all patients (7 d); after that, patients in the control group received routine medication (7 d), and those in the treatment group were treated with Shengji ointment until the wounds were healed, so as to compare their wound healing condition, ARRs, levels of inflammatory factors, and infection incidence.

Results

Compared with the control group after treatment, the treatment group presented significantly shorter wound healing time (12.14 ± 1.26 vs. 15.98 ± 1.20, P < 0.001), better wound healing rate and quality (P < 0.05), and lower levels of inflammatory factors (P < 0.001); no significant between-group difference in ARRs was shown (P > 0.05); 34 patients in the treatment group (85.0%) and 26 patients in the control group (65.0%) had no infections, so the incidence rate of infections was significantly lower in the treatment group than in the control group (P < 0.05).

Conclusion

Combining immersion therapy with Shengji ointment can reduce the levels of inflammatory factors in patients with second-degree burn, lower the incidence rate of infections, provide the conditions for wound healing, and increase the wound healing rate, which shall be promoted and applied in practice.