Smart Polymeric Hydrogels for Cartilage Tissue Engineering: A Review on the Chemistry and Biological Functions.

Stimuli responsive hydrogels (SRHs) are attractive bioscaffolds for tissue engineering. The structural similarity of SRHs to the extracellular matrix (ECM) of many tissues offers great advantages for a minimally invasive tissue repair. Among various potential applications of SRHs, cartilage regeneration has attracted significant attention. The repair of cartilage damage is challenging in orthopedics owing to its low repair capacity. Recent advances include development of injectable hydrogels to minimize invasive surgery with nanostructured features and rapid stimuli-responsive characteristics. Nanostructured SRHs with more structural similarity to natural ECM up-regulate cell-material interactions for faster tissue repair and more controlled stimuli-response to environmental changes. This review highlights most recent advances in the development of nanostructured or smart hydrogels for cartilage tissue engineering. Different types of stimuli-responsive hydrogels are introduced and their fabrication processes through physicochemical procedures are reported. The applications and characteristics of natural and synthetic polymers used in SRHs are also reviewed with an outline on clinical considerations and challenges.

Curcumin loading potentiates the neuroprotective efficacy of Fe3O4 magnetic nanoparticles in cerebellum cells of schizophrenic rats.

BACKGROUND: The aim of this study was to investigate the neurotoxic effects of Fe3O4 magnetic- CurNPs on isolated schizophrenia mitochondria of rats as an in vivo model. METHODS: We designed CMN loaded superparamagnetic iron oxide nanoparticles (SPIONs) (Fe3O4 magnetic- CurNPs) to achieve an enhanced therapeutic effect. The physicochemical properties of Fe3O4 magnetic- CurNPs were characterized using X-ray diffraction (XRD), and dynamic laser light scattering (DLS) and zeta potential. Further, to prove Fe3O4 magnetic- CurNPs results in superior therapeutic effects, and also, the mitochondrial membrane potential collapse, mitochondrial complex II activity, reactive oxygen species generation, ATP level, cytochrome c release and histopathology of cerebellums were determined in brains of schizophrenic rats. RESULTS: We showed that effective treatment with CMN reduced or prevented Fe3O4 magnetic-induced oxidative stress and mitochondrial dysfunction in the rat brain probably, as well as mitochondrial complex II activity, MMP, and ATP level were remarkably reduced in the cerebellum mitochondria of treated group toward control (p < 0.05). Therewith, ROS generation, and cytochrome c release were notably (p < 0.05) increased in the cerebellum mitochondria of treated group compared with control group. CONCLUSION: Taken together, Fe3O4 magnetic- CurNPs exhibits potent antineurotoxicity activity in cerebellums of schizophrenic rats. This approach can be extended to preclinical and clinical use and may have importance in schizophernia treatment in the future. To our knowledge this is the first report that provides the Fe3O4 magnetic- CurNPs could enhance the neuroprotective effects of CMN in the Schizophrenia.