Three-dimensional (3D) tissue/organ printing is a major aspect of recent innovation in the field of tissue engineering and regenerative medicine. 3D tissue/organ printing aims to create 3D living tissue/organ analogues, and have evolved along with advances in 3D printing techniques. A diverse range of computer-aided 3D printing techniques have been applied to dispose living cells together with biomaterials and supporting biochemical factors within pre-designed 3D tissue/organ analogues. Recent developments in printable biomaterials, such as decellularized extracellular matrix bio-inks have enabled improvements in the functionality of the resulting 3D tissue/organ analogues. Here, we provide an overview of the 3D printing techniques and biomaterials that have been used, including the development of 3D tissue/organ analogues. In addition, in vitro models are described, and future perspectives in 3D tissue/organ printing are identified.
Biocompatible Materials ; Extracellular Matrix ; In Vitro Techniques ; Printing, Three-Dimensional ; Regenerative Medicine ; Tissue Engineering

BACKGROUND/OBJECTIVES: A pivotal role of oxidative stress has been emphasized in the pathogenesis as well as in the disease progression of Parkinson's disease (PD). We aimed at investigating serum levels of antioxidant vitamins and elucidating whether they could be associated with the pathogenesis and progression of PD. MATERIALS/METHODS: Serum levels of retinol, α- and γ-tocopherols, α- and β-carotenes, lutein, lycopene, zeaxanthin and β-cryptoxanthin were measured and compared between 104 patients with idiopathic PD and 52 healthy controls matched for age and gender. In order to examine the relationship between antioxidant vitamins and the disease progression, multiple group comparisons were performed among the early PD (Hoehn and Yahr stage I and II, N = 47), advanced PD (stage III and IV, N = 57) and control groups. Separate correlation analyses were performed between the measured antioxidant vitamins and clinical variables, such as Hoehn and Yahr stage and Unified Parkinson's Disease Rating Scale (UPDRS) motor score. RESULTS: Compared to controls, PD patients had lower levels of α- and β-carotenes and lycopene. α-carotene, β-carotene and lycopene levels were significantly reduced in advanced PD patients relative to early PD patients and were negatively correlated with Hoehn and Yahr stage and UPDRS motor score in PD patients. No significant differences were found in serum levels of retinol, α- and γ-tocopherols, and other carotenoids between PD patients and controls. No significant correlations were found between these vitamin levels and clinical variables in PD patients. CONCLUSIONS: We found that serum levels of some carotenoids, α-carotene, β-carotene and lycopene, were lower in PD patients, and that these carotenoids inversely correlated with clinical variables representing disease progression. Our findings suggest that decreases in serum α-carotene, β-carotene and lycopene may be associated with the pathogenesis as well as progression of PD.
Carotenoids ; Disease Progression ; Humans ; Lutein ; Oxidative Stress ; Parkinson Disease* ; Tocopherols* ; Vitamin A* ; Vitamins ; Zeaxanthins

BACKGROUND: Exosomes, nano-sized vesicles ranging between 30 and 150 nm secreted by human cells, play a pivotal role in long-range intercellular communication and have attracted significant attention in the field of regenerative medicine. Nevertheless, their limited productivity and cost-effectiveness pose challenges for clinical applications. These issues have recently been addressed by cell-derived nanovesicles (CDNs), which are physically synthesized exosome-mimetic nanovesicles from parent cells, as a promising alternative to exosomes. CDNs exhibit structural, physical, and biological properties similar to exosomes, containing intracellular protein and genetic components encapsulated by the cell plasma membrane. These characteristics allow CDNs to be used as regenerative medicine and therapeutics on their own, or as a drug delivery system. METHODS: The paper reviews diverse methods for CDN synthesis, current analysis techniques, and presents engineering strategies to improve lesion targeting efficiency and/or therapeutic efficacy. RESULTS: CDNs, with their properties similar to those of exosomes, offer a cost-effective and highly productive alternative due to their non-living biomaterial nature, nano-size, and readiness for use, allowing them to overcome several limitations of conventional cell therapy methods. CONCLUSION Ongoing research and enhancement of CDNs engineering, along with comprehensive safety assessments and stability analysis, exhibit vast potential to advance regenerative medicine by enabling the development of efficient therapeutic interventions.