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Background: Cornea injury of sulfur mustard (SM) is considered as the most devastating injuries to the eye. This study aimed to evaluate the single and combined effects of N-acetyl cysteine (NAC) and doxycycline on the inflammatory pathway and cornea neovascularization (CNV) in the rat model of SM-injured cornea. Materials and methods: The right cornea of male Sprague-Dawley rats was subjected to 2-chloroethyl-ethyl sulfide (CEES). Rats were topically treated with a single and combined of 0.5% NAC and 12.5 lg/ml doxycycline and examined at 3rd, 15th, and 21st days. The activity of three antioxidant enzymes was analyzed in the cornea of different groups. Real-time PCR was performed to measure gene expression of inflammatory factors (tnf-a, rel-a & cxcl-1) and angiogenesis factors (vegf-a, mmp2,9) in the cornea lysates. The histological and opacity assessments were also carried out. Results: The activity of antioxidant enzymes significantly declined 3 days after the CEES damage. NAC eye drop recovered the enzyme activity on the 21st day of treatment (p-value < .05). The expression of tnf-a and rel-a genes significantly increased after CEES cornea exposure, while NAC declined their expression on the 7th and 21st days. The CNV score and angiogenesis factor expression were decreased in the long term by single and combined treatments (p-value < .05), but the infiltration of inflammatory cells was not completely amended. Conclusion: NAC and doxycycline eye drop could improve the CNV complication. Also, NAC was an effective treatment against the inflammatory pathway involved in CEES-injured cornea.

Background: Today, the effects of growth factors and mesenchymal stem cells (MSCs) in promoting wound healing have been confirmed. Objective: This study aimed to investigate the effect of MSCs and platelet cryogel on wound healing. Methods: 40 male Wistar rats were randomly divided into five groups (n=8). The control group just dressed, the second group received platelet cryogel, the third group received platelet cryogel containing MSCs, the fourth group received plasma, and the fifth group received plasma plus MSCs. The biopsy was obtained from the wounds in 2, 4, 6, and 8 days of the treatment. Then pathological evaluation was conducted. Finally, qRT-PCR was performed to determine angiogenesis. Results: The intervention groups had faster wound healing and lower wound area than the control group (p<0.05). The highest wound healing rate and the smallest wound area were observed in the group after receiving platelet cryogel plus MSCs. Angiogenesis, fibrosis, myoepithelial and epithelialization in the pathologic examination using H & E staining were not significantly different between the groups. The expression of Ang-1 in the intervention groups was higher than the control group and the highest expression was observed in the platelet cryogel plus MSCs, followed by the platelet cryogel group. The expression of VEGF in the plasma plus MSCs was higher than in the other groups. Conclusion: Further studies require to determine the effects of combined use of platelet cryogel plus MSCs on other types of wounds and evaluate mechanisms involved in wound healing like collagenases and inflammatory factors.