Proliferative and Osteogenic Supportive Effect of VEGF-Loaded Collagen-Chitosan Hydrogel System in Bone Marrow Derived Mesenchymal Stem Cells.

The use of hydrogel (HG) in regenerative medicine is an emerging field and thus several approaches have been proposed recently to find an appropriate hydrogel system. In this sense, this study developed a novel HG system using collagen, chitosan, and VEGF composites for culturing mesenchymal stem cells (MSCs), and investigated their ability for osteogenic differentiation and mineral deposition. Our results showed that the HG loaded with 100 ng/mL VEGF (HG-100) significantly supported the proliferation of undifferentiated MSCs, the fibrillary filament structure (HE stain), mineralization (alizarin red S and von Kossa stain), alkaline phosphatase, and the osteogenesis of differentiated MSCs compared to other hydrogels (loaded with 25 and 50 ng/mL VEGF) and control (without hydrogel). HG-100 showed a higher VEGF releasing rate from day 3 to day 7 than other HGs, which substantially supports the proliferative and osteogenic properties of HG-100. However, the HGs did not increase the cell growth in differentiated MSCs on days 14 and 21 due to the confluence state (reach stationary phase) and cell loading ability, regardless of the VEGF content. Similarly, the HGs alone did not stimulate the osteogenesis of MSCs; however, they increased the osteogenic ability of MSCs in presence of osteogenic supplements. Accordingly, a fabricated HG with VEGF could be used as an appropriate system to culture stem cells for bone and dental regeneration.

Fabrication of Chinese Traditional Medicines incorporated collagen biomaterials for human bone marrow mesenchymal stem cells.

Chinese Traditional Medicines (CTMs) are very popular for therapeutic applications to cure several chronic diseases. Many researchers are trying to discover the potential application and actual mechanism of CTMs in order to scientifically prove their effects for commercial use. One of the main functions of CTMs is to aid stem cell regeneration. Since, this study was focused to fabricate CTMs incorporated fish collagen film, which has good biocompatibility in mammalian cell growth and thus investigated the effect on human Mesenchymal stem cells (hMSCs) proliferation and differentiation. In this study, three types of CTMs such as Genistein, Icariin, and Naringin were used for film fabrication. Mechanical properties of collagen films were improved by the addition of CTMs, especially in Collagen-Naringin films. Solubility and In-vitro biodegradation of collagen films were enhanced by the hydrophobicity and chemical interaction of CTMs with collagen. The proliferation rate was accelerated in hMSCs cultured on CTMs incorporated collagen films in a dose- and time-dependent manner. Proliferation biomarkers such as Ki-67 and BrdU levels were higher in hMSCs cultured on CTMs incorporated collagen films. The proliferative and differentiation effect of CTMs was further confirmed by higher gene expression of Collagen I, Runx2, c-Fos, SMAD3 and TGF-ß1 in hMSCs. Overall, this study provides a new insight on novel biomaterial fabrication using CTMs and fish collagen for making a compatible platform for in-vitro stem cell culture.

Natural Triterpenoids Isolated from Akebia trifoliata Stem Explants Exert a Hypoglycemic Effect via α-Glucosidase Inhibition and Glucose Uptake Stimulation in Insulin-Resistant HepG2 Cells.

The inhibition of α-glucosidase activity is a prospective approach to attenuate postprandial hyperglycemia in the treatment of type 2 diabetes mellitus (T2DM). Herein, the inhibition of α-glucosidase by three compounds T1 -T3 of Akebia trifoliata stem, namely hederagenin (T1 ), 3-epiakebonoic acid (T2 ), and arjunolic acid (T3 ) were investigated using enzyme kinetics and molecular docking analysis. The three triterpenoids exhibited excellent inhibitory activities against α-glucosidase. T1 -T3 showed the strongest inhibition with IC50 values of 42.1±5.4, 19.6±3.2, and 11.2±2.3 µM, respectively, compared to the acarbose positive control (IC50 =106.3±8.2). Enzyme inhibition kinetics showed that triterpenoids T1 -T3 demonstrated competitive, mixed, and noncompetitive-type inhibition against α-glucosidase, respectively. The inhibition constant (Ki ) values were 21.21, 7.70, and 3.18 µM, respectively. Docking analysis determined that the interaction of ligands T1 -T3 and α-glucosidase was mainly forced by hydrogen bonds and hydrophobic interactions, which could result in improved binding to the active site of the target enzyme. The insulin resistant (IR)-HepG2 cell model used in this study (HepG2 cells exposed to 10-7  M insulin for 24 h) and glucose uptake assays showed that compounds T1 -T3 had no cytotoxicity with concentrations ranging from 6.25 to 25 µM and displayed significant stimulation of glucose uptake in IR-HepG2 cells. Thus, triterpenoids T1 -T3 showed dual therapeutic effects of α-glucosidase inhibition and glucose uptake stimulation and could be used as potential medicinal resources to investigate new antidiabetic agents for the prevention or treatment of diabetes.

Resveratrol and Celastrol Loaded Collagen Dental Implants Regulate Periodontal Ligament Fibroblast Growth and Osteoclastogenesis of Bone Marrow Macrophages.

Collagen is widely used for dental therapy in several ways such as films, 3D matrix, and composites, besides traditional Chinese medicine (TCM), has been used in tissue regeneration and wound healing application for centuries. Hence, the present study was targeted for the first time to fabricate collagen film with TCM such as resveratrol and celastrol in order to investigate the human periodontal ligament fibroblasts (HPLF) growth and bone marrow macrophages (BMM) derived osteoclastogenesis. Further, the physicochemical, mechanical and biological activities of collagen-TCM films crosslinked by glycerol and EDC-NHS (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide-N-hydroxysulfosuccinimide) were investigated. Collagen film characterization was significantly regulated by the nature of plasticizers like hydrophobic and degree of polarity. Interestingly, the collagen film's denaturation temperature was increased by EDC-NHS than glycerol. FT-IR data confirmed the functional group changes due to chemical interaction of collagen with TCM. Morphological changes of HPLF cells cultured in control and collagen films were observed by SEM. Importantly, the addition of resveratrol upregulated the proliferation of HPLF cells, while osteoclastogenesis of BMM cells treated with mCSF-RANKL was significantly downregulated by celastrol. Accordingly, the collagen-TCM film could be an interesting material for dental regeneration, and especially it is a therapeutic target to restrain the elevated bone resorption during osteoporosis.

Evaluation of Marine Diindolinonepyrane in Vitro and in Vivo: Permeability Characterization in Caco-2 Cells Monolayer and Pharmacokinetic Properties in Beagle Dogs.

A marine fibrinolytic compound was studied for use in thrombolytic therapy. Firstly, the absorption and transportation characteristics of 2,5-BHPA (2,5-BHPA:2,5-Bis-[8-(4,8-dimethyl-nona-3,7-dienyl)-5,7-dihydroxy-8-methyl-3-keto-1,2,7,8-tertahydro-6H-pyran[a]isoindol-2-yl]-pentanoic acid, a novel pyran-isoindolone derivative with bioactivity isolated from a rare marine microorganism in our laboratory) in the human Caco-2 cells monolayer model were investigated. We collected 2,5-BHPA in the cells to calculate the total recovery, and its concentration was analyzed by LC/MS/MS (Liquid Chromatography/ Mass Spectrum/ Mass Spectrum). The results showed that 2,5-BHPA has low permeability and low total recoveries in the Caco-2 cells membrane. Pharmacokinetics and tissue distribution of 2,5-BHPA were investigated in beagle dogs using HPLC (High Performance Liquid Chromatography) after intravenous administration of three different doses (7.5, 5.0, 2.5 mg·kg-1). Pharmacokinetic data indicated that 2,5-BHPA fitted well to a two-compartment model. Elimination half-lives (T1/2) were 49 ± 2, 48 ± 2, and 49 ± 2 min, respectively; the peak concentrations (Cmax) were 56.48 ± 6.23, 48.63 ± 5.53, and 13.64 ± 2.76 µg·mL-1, respectively; clearance rates (CL) were 0.0062 ± 0.0004, 0.0071 ± 0.0008, and 0.0092 ±0.0006 L·min-1·kg-1, respectively; mean retention times (MRT) were 28.17 ± 1.16, 26.23 ± 0.35, and 28.66 ± 0.84 min, respectively. The low penetrability of 2,5-BHPA indicated that the intravenous route of administration is more appropriate than the oral route. Meanwhile, 2,5-BHPA showed a good pharmacokinetic profile in beagle dogs. The tissue distribution showed that 2,5-BHPA could quickly distribute into the heart, intestines, liver, stomach, spleen, lungs, testicles, urine, intestine, kidneys, brain, and feces. The concentration of 2,5-BHPA was higher in the liver and bile. Interestingly, 2,5-BHPA was detected in the brain. Taken together, the above results suggested that our work might be beneficial in the development of agents for thrombolytic treatment.