Exosomes from human induced pluripotent stem cells-derived keratinocytes accelerate burn wound healing through miR-762 mediated promotion of keratinocytes and endothelial cells migration.

BACKGROUND: The use of keratinocytes derived from induced pluripotent stem cells (iPSCs-KCs) may represent a novel cell therapy strategy for burn treatment. There is growing evidence that extracellular vesicles, including exosomes, are primary mediators of the benefits of stem cell therapy. Herein, we thus explored the effects of exosomes produced by iPSCs-derived keratinocytes (iPSCs-KCs-Exos) in a model of deep second-degree burn wound healing and evaluated the mechanistic basis for the observed activity. METHODS: iPSCs-KCs-Exos were isolated from conditioned medium of iPSCs-KCs and verified by electron micrograph and size distribution. Next, iPSCs-KCs-Exos were injected subcutaneously around wound sites, and its efficacy was evaluated by measuring wound closure areas, histological examination, and immunohistochemistry staining. The effects of iPSCs-KCs-Exos on proliferation and migration of keratinocytes and endothelial cells in vitro were assessed by EdU staining, wound healing assays, and transwell assay. Then, high-throughput microRNA sequencing was used to explore the underlying mechanisms. We assessed the roles of miR-762 in iPSCs-KCs-Exos-induced regulation of keratinocytes and endothelial cells migration. Furthermore, the target gene which mediated the biological effects of miR-762 in keratinocytes and endothelial cells was also been detected. RESULTS: The analysis revealed that iPSCs-KCs-Exos application to the burn wound drove the acceleration of wound closure, with more robust angiogenesis and re-epithelialization being evident. Such iPSCs-KCs-Exos treatment effectively enhanced endothelial cell and keratinocyte migration in vitro. Moreover, the enrichment of miR-762 was detected in iPSCs-KCs-Exos and was found to target promyelocytic leukemia (PML) as a means of regulating cell migration through a mechanism tie to integrin beta1 (ITGB1). CONCLUSION: These results thus provide a foundation for the further study of iPSCs-KCs-Exos as novel cell-free treatments for deep second-degree burns.

Exosomes derived from miR-16-5p-overexpressing keratinocytes attenuates bleomycin-induced skin fibrosis.

microRNAs have been shown to be associated with the development of skin fibrosis. Therefore, miRNA modulators play an important role in the management of cutaneous fibrotic diseases and are worthy of investigation. However, a major obstacle of miRNAs therapy is to deliver miRNAs to target cell types, tissues or organs. The study reported here investigated the effects of miR-16-5p delivery by keratinocytes-derived exosomes on skin fibrosis in the bleomycin (BLM)-treated mice. In results, miR-16-5p-overexpressing keratinocytes-derived exosomes significantly suppressed the enhancing effects of TGF-ß1 on proliferation, migration and COL1A1 expression of fibroblasts. Moreover, we found that miR-16-5p-overexpressing keratinocytes-derived exosomes inhibited the endogenous Smad3 expression. In vivo, subcutaneously injected of miR-16-5p-overexpressing keratinocytes-derived exosomes significantly enhanced miR-16-5p expression in the skin compared with the control group, while suppressing BLM-induced skin fibrosis with reduced dermal thickening and lower COL1A1 expression. In conclusion, our results suggest that the localized delivery of miR-16-5p by keratinocytes-derived exosomes may have potential for efficient clinical treatment of skin fibrosis.

Induced pluripotent stem cells-derived microvesicles accelerate deep second-degree burn wound healing in mice through miR-16-5p-mediated promotion of keratinocytes migration.

Background: Induced pluripotent stem cells (iPSCs) have emerged as a promising treatment paradigm for skin wounds. Extracellular vesicles are now recognized as key mediators of beneficial stem cells paracrine effects. In this study, we investigated the effect of iPSCs-derived microvesicles (iPSCs-MVs) on deep second-degree burn wound healing and explored the underlying mechanism. Methods: iPSCs-MVs were isolated and purified from conditioned medium of iPSCs and confirmed by electron micrograph and size distribution. In deep second-degree burn model, iPSCs-MVs were injected subcutaneously around wound sites and the efficacy was assessed by measuring wound closure areas, histological examination and immunohistochemistry staining. In vitro, CCK-8, EdU staining and scratch assays were used to assess the effects of iPSCs-MVs on proliferation and migration of keratinocytes. Next, we explored the underlying mechanisms by high-throughput microRNA sequencing. The roles of the miR-16-5p in regulation of keratinocytes function induced by iPSCs-MVs were assessed. Moreover, the target gene which mediated the biological effects of miR-16-5p in keratinocytes was also been detected. Finally, we examined the effect of local miR-16-5p treatment on deep second degree-burns wound healing in mice. Results: The local transplantation of iPSCs-MVs into the burn wound bed resulted in accelerated wound closure including the increased re-epithelialization. In vitro, iPSCs-MVs could promote the migration of keratinocytes. We also found that miR-16-5p is a critical factor in iPSCs-MVs-induced promotion of keratinocytes migration in vitro through activating p38/MARK pathway by targeting Desmoglein 3 (Dsg3). Finally, we confirmed that local miR-16-5p treatment could boost re-epithelialization during burn wound healing. Conclusion: Therefore, our results indicate that iPSCs-MVs-derived miR-16-5p may be a novel therapeutic approach for deep second-degree burn wound healing.

A Comparison on Prevalence of Hypertension and Related Risk Factors between Island and Rural Residents of Dalian City, China.

This study aimed to compare the prevalence of hypertension between the island and rural residents in Dalian, China, and to explore associated risk factors of hypertension in order to provide evidence for the establishment of targeted strategy of hypertension prevention and treatment for island and rural residents. The modified MONICA questionnaire survey was performed on 7764 island and rural residents aged ≥40 years (including 2652 island residents and 5112 rural residents). Our data showed that totally weighted prevalence of hypertension was significantly higher in rural residents than in island residents (61.9% vs. 55.2%, P<0.001). Multivariate binary logistic regression analysis showed that older age, higher BMI, lower education level, and higher LDL-C and UA levels were independently associated with increased risk of having hypertension both in island and in rural residents. The weighted awareness rate (29.9% vs. 17.3%, P<0.001), treatment rate (51.4% vs. 28.5%, P<0.001), and control rate (36.3% vs. 24.0%, P=0.001) of hypertension were all significantly higher in island residents than those in rural residents. In conclusion, our survey shows that the epidemics of hypertension are extremely high in surveyed residents in island and rural areas of Dalian city, while awareness, treatment, and control rats of hypertension in these residents are much lower than the national level. The scenario is even worse in rural residents as compared with island residents of Dalian, China.

Metabolomic study for essential hypertension patients based on dried blood spot mass spectrometry approach.

Hypertension is an increasingly serious public-health challenge worldwide. The traditional blood pressure measurement method could easily and reliably detect blood pressure. However, the delayed symptom onset may influence the screening of essential hypertension (EH). In addition, EH is significantly associated to cardiovascular disease, stroke and kidney disease. Hence, it is urgent to define associated biomarkers with early diagnosis potential for EH. A dried blood spot method integrated with direct infusion mass spectrometry (MS) metabolomic analysis was applied for the detection of metabolites toward 87 EH patients and 91 healthy controls (HC). Multiple algorithms were run on training set (62 EH and 64 HC) for selecting differential metabolites as potential biomarkers. A test set (25 EH and 27 HC) was used to verify and evaluate selected potential biomarkers. A novel blood biomarker model based on Gly, Orn, C10, Orn/Cit, Phe/Tyr, and C5-OH/C8 exhibited potential to differentiate EH patients from HC individuals, with a sensitivity of 0.8400 and a specificity of 0.8889 in test set. The metabolomic analysis of EH is beneficial to the definition of disease-associated biomarkers and the development of new diagnostic approaches. © 2018 IUBMB Life, 70(8):777-785, 2018.

Thymoquinone protects against cardiac damage from doxorubicin-induced heart failure in Sprague-Dawley rats.

Heart failure is a complex end stage result of various cardiovascular diseases, and has a poor prognosis. The mechanisms for the development and progression of heart failure have always been an important topic in cardiovascular research, and previous studies have shown that thymoquinone (TQ) protects against cardiotoxicity and cardiac damage. The aim of this study was to investigate the possible protective effects of thymoquinone against cardiac damage in doxorubicin (DOX)-induced heart failure in Sprague-Dawley Rats (SDR). Forty-five male SDR were randomly divided into three groups and administered different treatment regimens for 8 weeks. Left ventricular fractional shortening (LVFS) and ejection fraction (LVEF) were higher in the DOX + TQ group than those in the DOX group. Significant pathophysiology changes (HE and Masson staining) were observed in rats of the DOX group compared to those of the DOX + TQ group. The addition of Thymoquinone inhibited DOX-induced cardiac fibrosis (TGF-ß, Smad3, collagen I, collagen III, and α-SMA) and apoptosis (P53, bcl-2, caspase-3, caspase-9, and BAX) in SDR, indicating that thymoquinone may be a potential therapeutic target for cardiac damage caused by DOX-induced heart failure.

Omega-3 polyunsaturated fatty acids prevent murine dilated cardiomyopathy by reducing oxidative stress and cardiomyocyte apoptosis.

Mice that lacked manganese-superoxide dismutase (Mn-SOD) activity exhibited the typical pathology of dilated cardiomyopathy (DCM). The aim of the present study was to investigate the effect of supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFA) on heart function and oxidative stress biomarkers in mice with DCM. In the present study, heart/muscle-specific Mn-SOD-deficient mice (H/M-Sod2-/-) were treated with n-3 PUFA (30 mg/kg/day) for 10 weeks, and the reactive oxygen species (ROS) production in their heart mitochondria and cardiac function was subsequently assessed. n-3 PUFA treatment diminished ROS production and suppressed the progression of cardiac dysfunction. Furthermore, n-3 PUFA treatment effectively reversed the cardiac dysfunction and dilatation observed in symptomatic H/M-Sod2-/- mice. Notably, n-3 PUFA treatment ameliorated a molecular defect in connexin 43. Hematoxylin-eosin staining indicated that the phenotype of DCM was also ameliorated following n-3 PUFA treatment. Furthermore, echocardiography demonstrated that cardiac function was significantly improved in the mice treated with n-3 PUFA (P<0.05). Meanwhile, pre-treatment with n-3 PUFA significantly decreased cardiomyocyte apoptosis (P<0.001). In conclusion, n-3 PUFA treatment is able to prevent murine DCM, primarily by reducing ROS production and improving myocardial apoptosis. Therefore, the impairment of ROS production is proposed as a potential therapy for DCM.

Beneficial effects of intramyocardial mesenchymal stem cells and VEGF165 plasmid injection in rats with furazolidone induced dilated cardiomyopathy.

To explore the impact of myocardial injection of mesenchymal stem cells (MSCs) and specific recombinant human VEGF165 (hVEGF165 ) plasmid on collagen remodelling in rats with furazolidone induced dilated cardiomyopathy (DCM). DCM was induced by furazolidone (0.3 mg/bodyweight (g)/day per gavage for 8 weeks). Rats were then divided into four groups: (i) PBS group (n = 18): rats received equal volume myocardial PBS injection; (ii) MSCs group (n = 17): 100 µl culture medium containing 10(5) MSCs were injected into four sites of left ventricular free wall (25 µl per site); (iii) GENE group (n = 18): pCMVen-MLC2v-EGFP-VEGF165 plasmid [5 × 10(9) pfu (0.2 ml)] were injected into four sites of left ventricular free wall (0.05 ml per site)] and (iv) MSCs+GENE group (n = 17): rats received both myocardial MSCs and pCMVen-MLC2v-EGFP-VEGF165 plasmid injections. After 4 weeks, cardiac function was evaluated by echocardiography. Myocardial mRNA expressions of type I, type III collagen and transforming growth factor (TGF)-ß1 were detected by RT-PCR. The protein expression of hVEGF165 was determined by Western blot. Myocardial protein expression of hVEGF165 was demonstrated in GENE and MSCs+GENE groups. Cardiac function was improved in MSCs, GENE and MSCs+GENE groups. Collagen volume fraction was significantly reduced and myocardial TGF-ß1 mRNA expression significantly down-regulated in both GENE and MSCs+GENE groups, collagen type I/III ratio reduction was more significant in MSCs+GENE group than in MSCs or GENE group. Myocardial MSCs and hVEGF165 plasmid injection improves cardiac function possibly through down-regulating myocardial TGF-ß1 expression and reducing the type I/III collagen ratio in this DCM rat model.

Impact of repeated intravenous bone marrow mesenchymal stem cells infusion on myocardial collagen network remodeling in a rat model of doxorubicin-induced dilated cardiomyopathy.

Bone marrow mesenchymal stem cells (MSCs) transplantation improved cardiac function and reduced myocardial fibrosis in both ischemic and non-ischemic cardiomyopathies. We evaluated the effects of repeated peripheral vein injection of MSCs on collagen network remodeling and myocardial TGF-ß1, AT1, CYP11B2 (aldosterone synthase) gene expressions in a rat model of doxorubicin (DOX)-induced dilated cardiomyopathy (DCM). Thirty-eight out of 53 SD rats survived at 10 weeks post-DOX injection (2.5 mg/kg/week for 6 weeks, i.p.) were divided into DCM blank (without treatment, n = 12), DCM placebo (intravenous tail injection of 0.5 mL serum-free culture medium every other day for ten times, n = 13), and DCM plus MSCs group (intravenous tail injection of 5 × 10(6) MSCs dissolved in 0.5 mL serum-free culture medium every other day for 10 times, n = 13). Ten untreated rats served as normal controls. At 20 weeks after DOX injection, echocardiography, myocardial collagen content, myocardial expressions of types I and III collagen, TGF-ß1, AT1, and CYP11B2 were compared among groups. At 20 weeks post-DOX injection, 8 rats (67%) survived in DCM blank group, 9 rats (69%) survived in DCM placebo group while 13 rats (100 %) survived in DCM plus MSCs group. Left ventricular end-diastolic diameter was significantly higher and ejection fraction was significantly lower in DCM blank and DCM placebo groups compared to normal control rats, which were significantly improved in DCM plus MSCs group (all p < 0.05 vs. DCM blank and DCM placebo groups). Moreover, myocardial collagen volume fraction, types I and III collagen, myocardial mRNA expressions of TGF-ß1, AT1, CYP11B2, and collagen I/III ratio were all significantly lower in DCM plus MSCs group compared to DCM blank and DCM placebo groups (all p < 0.05). Repeated intravenous MSCs transplantation could improve cardiac function by attenuating myocardial collagen network remodeling possibly through downregulating renin-angiotensin-aldosterone system in DOX-induced DCM rats.