AIM:To explore the inhibitory effect of a sustained cyclosporin A (CsA) delivery microsphere (CsA-MS) on posterior capsular opacification (PCO) in rabbit eyes after cataract extraction. ·METHODS:Twenty New Zealan...AIM:To explore the inhibitory effect of a sustained cyclosporin A (CsA) delivery microsphere (CsA-MS) on posterior capsular opacification (PCO) in rabbit eyes after cataract extraction. ·METHODS:Twenty New Zealand white rabbits accepted cataract extraction plus intraocular lens implantation and their left eyes were intraoperatively injected CsA-MS prepared using polymer polylactioglycolic acid (PLGA) as a carrier and their right eyes were injected with empty MS. The changes in cornea, anterior chamber reaction, intraocular pressure, PCO and CsA concentration in aqueous humor were examined postoperatively and all the eyes were enucleated 3 months after surgery for histopathological and morphological examination with light microscopy and electron microscopy. · RESULTS:Conjunctival hyperemia, corneal edema, intraocular pressure and anterior chamber response of experimental and control eyes were similar, while PCO in CsA MS injected eyes was greatly improved compared with that in control eyes. Posterior capsules in CsA-MS injected eyes were smooth and lens epithelial cells (LEC) did not proliferate significantly (P 】0.05), while LEC in posterior capsule of control eyes had different degrees of proliferation and cortical regeneration. LEC in CsA-MS injected eyes were not functionally active and underwent apoptosis, whereas LEC in control eyes were functionally active (F-test, P =0.025). In addition, the cornealultrastructure showed no differences between CsA-MS and MS injected eyes. CONCLUSION:CsA-MS has high bioavailability in rabbit eyes and could inhibit postoperative PCO occurrence and development during the study period, suggesting that CsA-MS may be a promising, effective and safe administration route to prevent PCO in clinic.展开更多
Although therapeutic potential of neurotrophic factors(NTFs)has been well recognized for over two decades,attempts to translate that potential to the clinic have been disappointing,largely due to significant obstacle...Although therapeutic potential of neurotrophic factors(NTFs)has been well recognized for over two decades,attempts to translate that potential to the clinic have been disappointing,largely due to significant obstacles in delivery,including inadequate protein dose/kinetics released at target sites.Considerable efforts have been made to improve the therapeutic performance of NTFs.This articles reviews recent developments in localized delivery systems of NTFs for the neurological disorders treatments with a main focus on sustained delivery strategies.Different non-covalent binding approaches have been employed to immobilize proteins in hydrogels,microspheres,electrospun nanofibers,and their combined systems,which serve as depots for sustained local release of NTFs.The challenges associated with current NTFs delivery systems and how these systems can be applied to neurological diseases and disorders have been discussed in the review.In conclusion,optimal delivery systems for NTFs will be needed for reliable and meaningful clinical benefits;ideally,delivering a time and dose-controlled release of bioactive multiNTFs at different individual optimal kinetics to achieve multi-functions in target tissues is significant preferred.展开更多
The use of nanotechnology in drug delivery is a rapidly expanding field. Biodegradable or nontoxic nanomaterials have the most promising application potentials in nanomedicine.
Although advances in protein assembly preparation have provided a new platform for drug delivery during tissue engineering,achieving long-term controlled exosome delivery remains a significant challenge.Diffusion-domi...Although advances in protein assembly preparation have provided a new platform for drug delivery during tissue engineering,achieving long-term controlled exosome delivery remains a significant challenge.Diffusion-dominated exosome release using protein hydrogels results in burst release of exosomes.Here,a fibroin-based cryo-sponge was developed to provide controlled exosome release.Fibroin chains can self-assemble into silk I structures under ice-cold conditions when annealed above the glass transition temperature.Exosome release is enzyme-responsive,with rates primarily determined by enzymatic degradation of the scaffolds.In vivo experiments have demonstrated that exosomes remain in undigested sponge material for two months,superior to their retention in fibrin glue,a commonly used biomaterial in clinical practice.Fibroin cryo-sponges were implanted subcutaneously in nude mice.The exosome-containing sponge group exhibited better neovascularization and tissue ingrowth effects,demonstrating the efficacy of this exosome-encapsulating strategy by realizing sustained release and maintaining exosome bioactivity.These silk fibroin cryo-sponges containing exosomes provide a new platform for future studies of exosome therapy.展开更多
基金National Natural Science Foundation of China (No. 81070721)Fundamental Research Funds for the Central Universities
文摘AIM:To explore the inhibitory effect of a sustained cyclosporin A (CsA) delivery microsphere (CsA-MS) on posterior capsular opacification (PCO) in rabbit eyes after cataract extraction. ·METHODS:Twenty New Zealand white rabbits accepted cataract extraction plus intraocular lens implantation and their left eyes were intraoperatively injected CsA-MS prepared using polymer polylactioglycolic acid (PLGA) as a carrier and their right eyes were injected with empty MS. The changes in cornea, anterior chamber reaction, intraocular pressure, PCO and CsA concentration in aqueous humor were examined postoperatively and all the eyes were enucleated 3 months after surgery for histopathological and morphological examination with light microscopy and electron microscopy. · RESULTS:Conjunctival hyperemia, corneal edema, intraocular pressure and anterior chamber response of experimental and control eyes were similar, while PCO in CsA MS injected eyes was greatly improved compared with that in control eyes. Posterior capsules in CsA-MS injected eyes were smooth and lens epithelial cells (LEC) did not proliferate significantly (P 】0.05), while LEC in posterior capsule of control eyes had different degrees of proliferation and cortical regeneration. LEC in CsA-MS injected eyes were not functionally active and underwent apoptosis, whereas LEC in control eyes were functionally active (F-test, P =0.025). In addition, the cornealultrastructure showed no differences between CsA-MS and MS injected eyes. CONCLUSION:CsA-MS has high bioavailability in rabbit eyes and could inhibit postoperative PCO occurrence and development during the study period, suggesting that CsA-MS may be a promising, effective and safe administration route to prevent PCO in clinic.
基金the National Natural Science Foundation of China(Grant No.81102401).
文摘Although therapeutic potential of neurotrophic factors(NTFs)has been well recognized for over two decades,attempts to translate that potential to the clinic have been disappointing,largely due to significant obstacles in delivery,including inadequate protein dose/kinetics released at target sites.Considerable efforts have been made to improve the therapeutic performance of NTFs.This articles reviews recent developments in localized delivery systems of NTFs for the neurological disorders treatments with a main focus on sustained delivery strategies.Different non-covalent binding approaches have been employed to immobilize proteins in hydrogels,microspheres,electrospun nanofibers,and their combined systems,which serve as depots for sustained local release of NTFs.The challenges associated with current NTFs delivery systems and how these systems can be applied to neurological diseases and disorders have been discussed in the review.In conclusion,optimal delivery systems for NTFs will be needed for reliable and meaningful clinical benefits;ideally,delivering a time and dose-controlled release of bioactive multiNTFs at different individual optimal kinetics to achieve multi-functions in target tissues is significant preferred.
基金supported by NSFC (no. 30700151)Academic Innovation Incubation Program from UESTC (no. Y02018023601062)in part by the Fujii-Otsuka International Scientific Exchange Fund from Tokushima University of Japan (795001002b)
文摘The use of nanotechnology in drug delivery is a rapidly expanding field. Biodegradable or nontoxic nanomaterials have the most promising application potentials in nanomedicine.
基金support from the Natural Science Foundation of Beijing Municipality(No.7171014)National Natural Science Foundation of China(No.81871770,81802101,81802153)+1 种基金National Key Research and Development Program of China(No.2016YFC1101301,2018YFF0301100)Beijing Nova Program Z201100006820011.
文摘Although advances in protein assembly preparation have provided a new platform for drug delivery during tissue engineering,achieving long-term controlled exosome delivery remains a significant challenge.Diffusion-dominated exosome release using protein hydrogels results in burst release of exosomes.Here,a fibroin-based cryo-sponge was developed to provide controlled exosome release.Fibroin chains can self-assemble into silk I structures under ice-cold conditions when annealed above the glass transition temperature.Exosome release is enzyme-responsive,with rates primarily determined by enzymatic degradation of the scaffolds.In vivo experiments have demonstrated that exosomes remain in undigested sponge material for two months,superior to their retention in fibrin glue,a commonly used biomaterial in clinical practice.Fibroin cryo-sponges were implanted subcutaneously in nude mice.The exosome-containing sponge group exhibited better neovascularization and tissue ingrowth effects,demonstrating the efficacy of this exosome-encapsulating strategy by realizing sustained release and maintaining exosome bioactivity.These silk fibroin cryo-sponges containing exosomes provide a new platform for future studies of exosome therapy.