ABSTRACT
Crassostrea sikamea (C.sikamea) is an important edible and medicinal seafood in China. In the present study, a compound named flazin was separated and identified from the ethyl acetate extract of C.sikamea (EAECs) for the first time. In addition, the 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetra zolium (MTS) assay revealed that EAECs and flazin inhibited the transformation of splenic lymphocytes in vitro. Moreover, flazin (20 μg·mL
Subject(s)
Animals , Rats , Carbolines , Crassostrea , Furans , Lymphocytes , Rats, Sprague-Dawley , SpleenABSTRACT
The idea of regenerating lost myocardium via cell-based therapies remains as highly considerable. C-kit? stem/progenitor cells are represented to be suitable candidates for cardiac regeneration compared to other stem cells.A multitude of cytokines from these cells are known to give such multifunctional properties; however, theassociated mechanisms of these factors are yet to be totally understood. The aim of the present study was toinvestigate the in vitro effect of L-carnitine (LC) on cardiac differentiation of c-kit? cells using a cytokinessecretion assay. For this purpose, bone-marrow-resident-c-kit? cells were enriched by MACS method, andwere differentiated to cardiac cells using cardiomyocyte differentiation medium in the absence (control group)and presence of LC (experimental group). Also, characterization of enriched c-kit? cells was performed usingflow cytometry and immunocytochemistry. In the following, the cells were subjected to real-time PCR andWestern blotting assay for gene and protein assessment, respectively. Afterward, culture medium was collectedfrom both control (-LC) and experimental groups (? LC) for cytokine measurement. It was found that 0.2mM LC significantly increased the mRNA and protein expression of cardiac markers of Ang-1, Ang-2, C-TnI,VEGF, vWF, and SMA in c-kit?-cardiomyogenic-differentiated cells. Also, the significant presence of IL-6,IGF-1, TGF-b, and VEGF were obvious in the cultured media from the experimental group compared with thecontrol group. It can be concluded that the mentioned in vitro effects of LC on cardiac differentiation of c-kit?cells could have resulted from the secreted cytokines IL-6, IGF-1, TGF-b, and VEGF.
ABSTRACT
Introduction:Mesenchymal stem cells (MSCs) hold a great therapeutic potential for regenerative medicine and tissue engineering due to inherent immunomodulatory and reparative properties. Hence, it necessitates a readily available supplyof MSCs to meet the clinical demands adequately. Although, a human placenta can produce MSCs, the in vitro culture-mediated cellular senescence often affect the quality of cell product. Thus, the current study has explored the feasibility of basic fibroblast growth factor (bFGF) to enhance the growth of placenta-derived MSCs (PLC-MSCs). Methods:The basic fibroblast growth factor (bFGF) was supplemented to optimise the growth of MSCs. The effects of bFGF on morphology, growth kinetics and cytokine secretion of PLC-MSCs were assessed. Results: The bFGF supplementation increased the proliferation of PLC-MSCs in a dose-dependent manner and 40 ng/ml showed a high trophism effect on PLC-MSC’s growth. In the presence of bFGF, PLC-MSCs acquired a small and well-defined morphology that reflect an active proliferative status. BFGF has induced PLC-MSCs to achieve a shorter doubling time (45 hrs) as compared to the non-supplemented PLC-MSCs culture (81 hrs). Furthermore, bFGF impelled PLC-MSCs into cell cycle machinery where a substantial fraction of cells was driven to S and G2/M phases. Amongst, 36 screened cytokines, bFGF had only altered the secretion of IL-8, IL-6, TNFR1, MMP3 and VEGF. Conclusion:The present study showed that bFGF supplementation promotes the growth of PLC-MSCs without significantly deviating from the standard criteria of MSCs. Thus, bFGF could be considered as a potential mitogen to facilitate the large-scale production of PLC-MSCs.
Subject(s)
Mesenchymal Stem CellsABSTRACT
Oral tolerance can be induced in some mouse strains by gavage or spontaneous ingestion of dietary antigens. In the present study, we determined the influence of aging and oral tolerance on the secretion of co-stimulatory molecules by dendritic cells (DC), and on the ability of DC to induce proliferation and cytokine secretion by naive T cells from BALB/c and OVA transgenic (DO11.10) mice. We observed that oral tolerance could be induced in BALB/c mice (N = 5 in each group) of all ages (8, 20, 40, 60, and 80 weeks old), although a decline in specific antibody levels was observed in the sera of both tolerized and immunized mice with advancing age (40 to 80 weeks old). DC obtained from young, adult and middle-aged (8, 20, and 40 weeks old) tolerized mice were less efficient (65, 17 and 20 percent, respectively) than DC from immunized mice (P < 0.05) in inducing antigen-specific proliferation of naive T cells from both BALB/c and DO11.10 young mice, or in stimulating IFN-g, IL-4 and IL-10 production. However, TGF-â levels were significantly elevated in co-cultures carried out with DC from tolerant mice (P < 0.05). DC from both immunized and tolerized old and very old (60 and 80 weeks old) mice were equally ineffective in inducing T cell proliferation and cytokine production (P < 0.05). A marked reduction in CD86+ marker expression was observed in DC isolated from both old and tolerized mice (75 and 50 percent, respectively). The results indicate that the aging process does not interfere with the establishment of oral tolerance in BALB/c mice, but reduces DC functions, probably due to the decline of the expression of the CD86 surface marker.