Enhancing chondrogenic differentiation of mesenchymal stem cells through synergistic effects of cellulose nanocrystals and plastic compression in collagen-based hydrogel for cartilage formation.

Collagen-based (COL) hydrogels could be a promising treatment option for injuries to the articular cartilage (AC) becuase of their similarity to AC native extra extracellular matrix. However, the high hydration of COL hydrogels poses challenges for AC's mechanical properties. To address this, we developed a hydrogel platform that incorporating cellulose nanocrystals (CNCs) within COL and followed by plastic compression (PC) procedure to expel the excessive fluid out. This approach significantly improved the mechanical properties of the hydrogels and enhanced the chondrogenic differentiation of mesenchymal stem cells (MSCs). Radially confined PC resulted in higher collagen fibrillar densities together with reducing fibril-fibril distances. Compressed hydrogels containing CNCs exhibited the highest compressive modulus and toughness. MSCs encapsulated in these hydrogels were initially affected by PC, but their viability improved after 7 days. Furthermore, the morphology of the cells and their secretion of glycosaminoglycans (GAGs) were positively influenced by the compressed COL-CNC hydrogel. Our findings shed light on the combined effects of PC and CNCs in improving the physical and mechanical properties of COL and their role in promoting chondrogenesis.

The effects of Wharton's jelly MSCs secretomes for restoring busulfan-induced reproductive toxicity in male mice.

Several studies investigated the application of Mesenchymal stem cells (MSCs) for treating spermatogenic disorders. Considering the limitation of MSC application, the present study aimed to compare Wharton's jelly MSCs secretomes, including condition medium (CM) 10-fold concentrated (CM10), 20-fold concentrated CM (CM20), and extracellular vesicles (EVs) to restore busulfan-induced damage on male mice reproduction. So, Wharton's jelly MSCs were cultured, CM was collected, and EVs were isolated. Seventy-two mice were randomly assigned to nine groups, including Control, Busulfan 1 month (1M), Busulfan 2 months (2M), CM10, Busulfan + CM10, CM20, Busulfan + CM20, EVs, and Busulfan + EVs groups. Sperm characteristics, DNA maturity, DNA fragmentation index (DFI), and testicular gene expression were evaluated. Data analysis revealed that CM10 significantly improved sperm plasma membrane integrity, sperm DNA maturity, and DFI in the Busulfan + CM10 group compared to the Busulfan 2M group. Although CM20 and EVs showed a non-significant improvement. Gene expression analysis showed busulfan administration significantly decreased the expression of AR, CREB1, and PLCζ genes, while CM10 significantly restored CREB1 gene expression. The present study demonstrated that CM10 is more effective than CM20 or EVs in reducing busulfan-induced reproductive toxicity.

Reconstructing Critical-Sized Mandibular Defects in a Rabbit Model: Enhancing Angiogenesis and Facilitating Bone Regeneration via a Cell-Loaded 3D-Printed Hydrogel-Ceramic Scaffold Application.

In this study, we propose a spatially patterned 3D-printed nanohydroxyapatite (nHA)/beta-tricalcium phosphate (ß-TCP)/collagen composite scaffold incorporating human dental pulp-derived mesenchymal stem cells (hDP-MSCs) for bone regeneration in critical-sized defects. We investigated angiogenesis and osteogenesis in a rabbit critical-sized mandibular defect model treated with this engineered construct. The critical and synergistic role of collagen coating and incorporation of stem cells in the regeneration process was confirmed by including a cell-free uncoated 3D-printed nHA/ß-TCP scaffold, a stem cell-loaded 3D-printed nHA/ß-TCP scaffold, and a cell-free collagen-coated 3D-printed nHA/ß-TCP scaffold in the experimental design, in addition to an empty defect. Posteuthanasia evaluations through X-ray analysis, histological assessments, immunohistochemistry staining, histomorphometry, and reverse transcription-polymerase chain reaction (RT-PCR) suggest the formation of substantial woven and lamellar bone in the cell-loaded collagen-coated 3D-printed nHA/ß-TCP scaffolds. Histomorphometric analysis demonstrated a significant increase in osteoblasts, osteocytes, osteoclasts, bone area, and vascularization compared to that observed in the control group. Conversely, a significant decrease in fibroblasts/fibrocytes and connective tissue was observed in this group compared to that in the control group. RT-PCR indicated a significant upregulation in the expression of osteogenesis-related genes, including BMP2, ALPL, SOX9, Runx2, and SPP1. The findings suggest that the hDP-MSC-loaded 3D-printed nHA/ß-TCP/collagen composite scaffold is promising for bone regeneration in critical-sized defects.

Curcumin prevents neuronal loss and structural changes in the superior cervical (sympathetic) ganglion induced by chronic sleep deprivation, in the rat model

BACKGROUND: In modern societies, sleep deprivation is a serious health problem. This problem could be induced by a variety of reasons, including lifestyle habits or neurological disorders. Chronic sleep deprivation (CSD) could have complex biological consequences, such as changes in neural autonomic control, increased oxidative stress, and inflammatory responses. The superior cervical ganglion (SCG) is an important sympathetic component of the autonomic nervous system. CSD can lead to a wide range of neurological consequences in SCG, which mainly supply innervations to circadian system and other structures. As the active component of Curcuma longa, curcumin possesses many therapeutic properties; including neuroprotective. This study aimed to evaluate the effect of CSD on the SCG histomorphometrical changes and the protective effect of curcumin in preventing these changes. METHODS: Thirty-six male rats were randomly assigned to the control, curcumin, CSD, CSD + curcumin, grid floor control, and grid floor + curcumin groups. The CSD was induced by a modified multiple platform apparatus for 21 days and animals were sacrificed at the end of CSD or treatment, and their SCGs removed for stereological and TUNEL evaluations and also spatial arrangement of neurons in this structure. RESULTS: Concerning stereological findings, CSD significantly reduced the volume of SCG and its total number of neurons and satellite glial cells in comparison with the control animals ( P < 0.05). Treatment of CSD with curcumin prevented these decreases. Furthermore, TUNEL evaluation showed significant apoptosis in the SCG cells in the CSD group, and treatment with curcumin significantly decreased this apoptosis ( P < 0.01). This decrease in apoptosis was observed in all control groups that received curcumin. CSD also changed the spatial arrangement of ganglionic neurons into a random pattern, whereas treatment with curcumin preserved its regular pattern. CONCLUSIONS: CSD could potentially induce neuronal loss and structural changes including random spatial distribution in the SCG neurons. Deleterious effects of sleep deprivation could be prevented by the oral administration of curcumin. Furthermore, the consumption of curcumin in a healthy person might lead to a reduction of cell death.