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Oxidative stress injury and mitochondrial dysfunction are major obstacles to neurological functional recovery after ischemic stroke. The development of new approaches to simultaneously diminish oxidative stress and resist mitochondrial dysfunction is urgently needed. Inspired by the overproduced reactive oxygen species (ROS) at ischemic neuron mitochondria, multifunctional nanoparticles with ROS-responsiveness and mitochondrial-targeted (SPNPs) were engineered, achieving specific targeting delivery and controllable drug release at ischemic penumbra. Due to the nose-to-brain pathway, SPNPs which were encapsulated in a thermo-sensitive gel by intranasal administration were directly delivered to the ischemic penumbra bypassing the blood‒brain barrier (BBB) and enhancing delivery efficiency. The potential of SPNPs for ischemic stroke treatment was systematically evaluated in vitro and in rat models of middle cerebral artery occlusion (MCAO). Results demonstrated the mitochondrial-targeted and protective effects of SPNPs on H2O2-induced oxidative damage in SH-SY5Y cells. In vivo distribution analyzed by fluorescence imaging proved the rapid and enhanced active targeting of SPNPs to the ischemic area in MCAO rats. SPNPs by intranasal administration exhibited superior therapeutic efficacy by alleviating oxidative stress, diminishing inflammation, repairing mitochondrial function, and decreasing apoptosis. This strategy provided a multifunctional delivery system for the effective treatment of ischemic injury, which also implies a potential application prospect for other central nervous diseases.
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COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread across the globe, posing an enormous threat to public health and safety. Traditional Chinese medicine (TCM), in combination with Western medicine (WM), has made important and lasting contributions in the battle against COVID-19. In this review, updated clinical effects and potential mechanisms of TCM, presented in newly recognized three distinct phases of the disease, are summarized and discussed. By integrating the available clinical and preclinical evidence, the efficacies and underlying mechanisms of TCM on COVID-19, including the highly recommended three Chinese patent medicines and three Chinese medicine formulas, are described in a panorama. We hope that this comprehensive review not only provides a reference for health care professionals and the public to recognize the significant contributions of TCM for COVID-19, but also serves as an evidence-based in-depth summary and analysis to facilitate understanding the true scientific value of TCM.
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BACKGROUND:Some Chinese herbal ingredients produce the analogical and pharmacological effects equivalent to growth factors, which can promote cel proliferation as wel as tissue and organ recovery and regeneration. Additional y, they possess low price and relative stable physicochemical property. Thus, the applications of traditional Chinese medicine in tissue engineering has attracted more attentions of researchers al over the world. OBJECTIVE:To review the application of the traditional Chinese medicine in stem cel proliferation and tissue engineering. METHODS:A computer-based retrieval of PubMed and CNKI databases was performed for articles concerning the application of traditional Chinese medicine in stem cel proliferation and tissue engineering published from 1978 to 2015. The keywords were“the traditional Chinese medicine, tissue engineering, application, stem cel , anti-inflammatory, cross linking, surface modification, osteoblast, blood vessel”in English and Chinese, respectively. RESULTS AND CONCLUSION:Natural medicine and the traditional Chinese medicine are expected to be applied in tissue engineering as a surrogate of growth factor and antibiotics, which exert anti-inflammatory, angiogenesis, surface modification, anticoagulation and cross-linking roles as wel as promote proliferation and differentiation of stem cel s in tissue engineering.
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BACKGROUND:Alginate-chitosan microcapsule can improve the mechanical property of sodium alginate hydrogels. How to obtain the ideal sodium alginate-chitosan microcapsule and the prospect for application of the microcapsule system is the key to this study. OBJECTIVE:To investigate the preparation method and formation mechanism of alginate-chitosan microcapsules, to analyze several important factors affecting the strength of the microcapsule membrane, and to explore the prospects of alginate-chitosan microcapsules in immobilized celltechnology, in tissue engineering and as a drug carrier. METHODS:The first author searched PubMed, Elsevier ScienceDirect, CNKI and Wanfang database (1987/2013) to retrieve literatures about the preparation method, formation mechanism and application prospect of alginate-chitosan microcapsules. RESULTS AND CONCLUSION:Sodium alginate hydrogels have many advantages in drug release and tissue engineering, but its application is limited by gel dissolution phenomena and deficiencies in its mechanical properties. Chitosan-alginate microcapsules make up for the deficiency of sodium alginate hydrogels by electrostatic interactions to form polyelectrolyte complexes. By control ing the nature of the chitosan solution--the molecular weight of chitosan, pH and concentration of chitosan solution, we can prepare the microcapsules with high film strength. Alginate-chitosan microcapsules have shown broad application prospects in immobilization technology, drug release and tissue engineering.
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Objective: To investigate the effect of icariin on the proliferation, differentiation, and the mRNA expressions of Cbfαl, BMP2, BMP4 of rat osteoblasts. Methods: Primary rat osteoblastic cells were obtained by sequentia collagenase/trypsin enzyme digestion from calvarial bones of new born ( within 24 h) SD rats and were identified by Alkaline phosphatase and alizarin red staining. The passage 3-5cells were treated with icariin at the concentration of 0 mol/L, 10~(-8)mol/L, 10~(-7)mol/L, 10~(-6)mol/L,10~(-5)mol/L, 10~(-4)mol/L for 24 h, 48 h, 72 h, and the proliferation of the cells was measured by CCK-8assay. The proliferation index was detected by Flow Cytometry and the activity of alkaline phosphatase was determined by p-Nitrophenyl phosphate (pNPP) method after being treated with icariin at the concentration mentioned above for 48 h. The total cellular RNA was extracted 48 h after being treated with icariin at the concentration of 10~(-6)mol/L, and the expressions of Cbfα1, BMP2, BMP4 mRNA were examined by real-time PCR. Results: Icariin showed no effect on the proliferation of osteoblasts, but improved ALP activity. The Cbfα1, BMP2, BMP4 mRNA were significantly upregulated after icariin treatment. Conclusion: Icariin could promote the differentiation ability of rat osteoblasts through upregulating the Cbfα1, BMP2, BMP4 mRNA expressions.