The therapeutical effects of damage-specific stress induced exosomes on the cisplatin nephrotoxicity IN VIVO.

Cisplatin is one of the metal containing drugs for the solid cancer treatments. However, its side-effects limit its application in the cancer treatment. Stem cell therapy is a promising treatment for the tissue damage caused by the chemotherapeutic agents, like cisplatin. Exosomes secreted by mesenchymal stem cells (MSCs) could be used for cell-free regenerative treatment, but their potency and reproducibility are questionable. In this study, the microenvironment of the renal tubular epithelial cells was mimicked by coculture of endothelial-, renal proximal tubule epithelial- and fibroblast cells. Cisplatin was applied to this tricell culture model, and the secreted rescue signals were collected and used to induce MSCs. From these stress-induced MSCs, the (stress-induced) exosomes were collected and used for the cell-free therapeutic treatment of cisplatin-treated rats with acute kidney injury. The composition of the stress-induces exosomes was compared with the non-induced exosomes and found that the expression of some critical factors for cell proliferation, repair mechanism and oxidative stress was improved. The cisplatin-damaged renal tissue showed substantial recovery after the treatment with stress-induced exosomes compared to the treatment with non-induced exosomes. Although, the non-induced exosomes showed their activity mostly as cytoprotective, the induced exosomes further involved actively in the tissue regeneration, like MSCs. It was shown that the exosomes could be reprogrammed to improve their therapeutic effect to be used in cell-free regenerative medicine. Further, cisplatin-induced tissue damage in the kidney might be effectively prevented and used for tissue regeneration by use of induced exosomes generated for a particular damage.

Comparative Analysis of Matrix-Regenerating Agent and Corneal Cross-Linking in an Experimental Alkali Burn Rabbit Model.

PURPOSE: This study aimed to investigate the clinical and histopathological effects of corneal cross-linking (CXL) and matrix-regenerating agent (RGTA) treatments after corneal alkali burn. MATERIALS AND METHODS: Twenty-four alkali-burned corneas from 24 rabbits were divided into three groups: control, CXL, and RGTA. All animals were investigated for epithelial healing, opacification, ulceration, and neovascularization at days 1, 7, 14, and 21 after the alkali burn. Corneas were excised and sent for histological examination on day 21. RESULTS: One animal each from the CXL and control groups exhibited moderate ulceration, while no ulceration was observed in the RGTA group. No significant difference was observed among the groups in corneal thickness or corneal opacity measurements at the final visit (p = .058 and p = .544, respectively). Both RGTA and CXL treatments were effective in terms of epithelial healing and neovascularization (p = .023 and p = .03, respectively). On histological examination, the CXL and RGTA groups were more effective in treating epithelial loss, stromal edema, corneal vascularization, and leukocytic infiltration than the control group (p < .05). The immunohistochemical staining scores of the CXL and RGTA groups for caspase-3, vascular endothelial growth factor, and matrix metalloproteinase-9 in the epithelium and stroma were significantly lower than those in the control group (p < .05). In the immunohistochemical examination for inducible nitric oxide synthase, epithelial staining scores were similar among the groups (p > .05). In contrast, the stromal staining scores of the CXL and RGTA groups were lower than those of the control group (p < .05). CONCLUSION: Both CXL and RGTA therapies were effective in reducing anatomical and histopathological complications after corneal alkali burn. Further investigation is needed to determine the optimal timing, duration, and dosage of these treatments.

Protective effects of apocynin on damaged testes of rats exposed to methotrexate

Background/aim: Methotrexate (MTX), widely used as a drug in cancer, has many adverse effects on tissues. Apocynin (APO) is a NADPH oxidase inhibitor and is known with many antioxidant properties. In this study, we aimed to evaluate the adverse effects of MTX on testicular tissue and the protective effects of APO at two different doses (20 mg/kg and 50 mg/kg) on MTX-induced testicular damage. Materials and methods: Fifty adult male Wistar albino rats (8 weeks old and weighing 200­250 g) were divided into five groups of 10 rats each: 1. saline control, 2. dimethyl sulfoxide (DMSO) control, 3. MTX, 4. APO-20 + MTX, and 5. APO-50 + MTX. All injections were performed intraperitoneally. At the end of day 28, all rats were sacrificed under anesthesia. The testes were evaluated histologically and the blood samples were analyzed biochemically. Results: According to histological and biochemical analyses, there was no significant difference between the DMSO and control groups. In terms of the histological findings, MTX group was significantly the worst affected group compared to the others, and in this group, apoptotic cell number (P = 0.011) was significantly increased in comparison with the control group. Except MTX, there was no significant difference in apoptotic cell number of the other groups compared to the control group. In the MTX group, malondialdehyde (MDA, P = 0.017) and myeloperoxidase (MPO, P < 0.001) levels were significantly increased in tissue and in blood (MDA P < 0.001, MPO P < 0.001), while tissue glutathione (GSH, P < 0.05) and serum testosterone levels (P < 0.01) were decreased compared with the control group. APO + MTX treatment groups exhibited better testis morphology, and apoptotic cells were also significantly decreased compared to MTX group (P < 0.001). Conclusion: Our results suggest that MTX induced defects on testis via oxidative stress and APO reversed the effects of MTX with its antioxidant properties.