We previously showed that green tea polyphenols (GTPs) exert antiadipogenic effects on preadipocyte proliferation. Here, we investigated the regulatory effects of GTPs on osteogenesis and adipogenesis during early differentiation of human adipose tissue-derived stem cells (hADSC). Adipogenesis of hADSCs was determined by oil-red-O staining and triglycerides synthesis measurement. Osteoporosis of hADSC was measured using alkaline phosphatase assays and intracellular calcium levels. Immunofluorescence staining and qRT-PCR were used to detect PPARγ-CEBPA regulated adipogenic pathway regulated by PPAR-CEBPA and the osteogenic pathway mediated by RUNX2-BMP2. We found that GTPs treatment significantly decreased lipid accumulation and cellular triglyceride synthesis in mature adipocytes and attenuated pioglitazone-induced adipogenesis in a dose-dependent manner. GTPs downregulated protein and mRNA expression of Pparγ and attenuated pioglitazone-stimulated-Cebpa expression. GTPs treatment significantly enhanced hADSCs differentiation into osteoblasts compared to control and pioglitazone-treated cells. GTPs upregulated RunX2 and Bmp2 proteins and mRNA expression compared to control and significantly attenuated decreased RunX2 and Bmp2 mRNA expression by pioglitazone. In conclusion, our data demonstrates GTPs possesses great ability to facilitate osteogenesis and simultaneously inhibits hADSC differentiation into adipogenic lineage by upregulating the RUNX2-BMP2 mediated osteogenic pathway and suppressing PPARγ-induced signaling of adipogenesis. These findings highlight GTPs’ potential to combat osteoporosis associated with obesity. 相似文献
Oxidative stress after ischaemia impairs the function of transplanted stem cells. Increasing evidence has suggested that either salidroside (SAL) or hypoxia regulates growth of stem cells. However, the role of SAL in regulating function of hypoxia‐pre–conditioned stem cells remains elusive. Thus, this study aimed to determine the effect of SAL and hypoxia pre‐conditionings on the proliferation, migration and tolerance against oxidative stress in rat adipose‐derived stem cells (rASCs). rASCs treated with SAL under normoxia (20% O2) or hypoxia (5% O2) were analysed for the cell viability, proliferation, migration and resistance against H2O2‐induced oxidative stress. In addition, the activation of Akt, Erk1/2, LC3, NF‐κB and apoptosis‐associated pathways was assayed by Western blot. The results showed that SAL and hypoxia treatments synergistically enhanced the viability (fold) and proliferation of rASCs under non‐stressed conditions in association with increased autophagic flux and activation of Akt, Erk1/2 and LC3. H2O2‐induced oxidative stress, cytotoxicity, apoptosis, autophagic cell death and NF‐κB activation were inhibited by SAL or hypoxia, and further attenuated by the combined SAL and hypoxia pre‐treatment. The SAL and hypoxia pre‐treatment also enhanced the proliferation and migration of rASCs under oxidative stress in association with Akt and Erk1/2 activation; however, the combined pre‐treatment exhibited a more profound enhancement in the migration than proliferation. Our data suggest that SAL combined with hypoxia pre‐conditioning may enhance the therapeutic capacity of ASCs in post‐ischaemic repair. 相似文献
Crystals in Bacillus thuringiensis are usually formed in the mother cell compartment during sporulation and are separated from the spores after mother cell lysis. In a few strains, crystals are produced inside the exosporium and are associated with the spores after sporulation. This special phenotype, named 'spore crystal association' (SCA), typically occurs in B. thuringiensis subsp. finitimus. Our aim was to identify genes determining the SCA phenotype in B. thuringiensis subsp. finitimus strain YBT-020. Plasmid conjugation experiments indicated that the SCA phenotype in this strain was tightly linked with two large plasmids (pBMB26 and pBMB28). A shuttle bacterial artificial chromosome (BAC) library of strain YBT-020 was constructed. Six fragments from BAC clones were screened from this library and discovered to cover the full length of pBMB26; four others were found to cover pBMB28. Using fragment complementation testing, two fragments, each of approximately 35 kb and located on pBMB26 and pBMB28, were observed to recover the SCA phenotype in an acrystalliferous mutant, B. thuringiensis strain BMB171. Furthermore, deletion analysis indicated that the crystal protein gene cry26Aa from pBMB26, along with five genes from pBMB28, were indispensable to the SCA phenotype. Gene disruption and frame-shift mutation analyses revealed that two of the five genes from pBMB28, which showed low similarity to crystal proteins, determined the location of crystals inside the exosporium. Gene disruption revealed that the three remaining genes, similar to spore germination genes, contributed to the stability of the SCA phenotype in strain YBT-020. Our results thus identified the genes determining the SCA phenotype in B. thuringiensis subsp. finitimus. 相似文献
Context: Diabetes is a growing global metabolic epidemic. Current research is focussing on exploring how the biological processes and clinical outcomes of diabetes are related and developing novel biomarkers to measure these relationships, as this can subsequently improve diagnostic, therapeutic and management capacity.
Objective: The objective of this study is to identify the most recent advances in molecular biomarkers of diabetes and directions that warrant further research.
Methods: Using a systematic search strategy, the MEDLINE, CINAHL and OVID MEDLINE databases were canvassed for articles that investigated molecular biomarkers for diabetes. Initial selections were made based on article title, whilst final inclusion was informed by a critical appraisal of the full text of each article.
Results: The systematic search returned 246 records, of which 113 were unique. Following screening, 29 records were included in the final review. Three main research strategies (the development of novel technologies, broad biomarker panels, and targeted approaches) identified a number of potential biomarkers for diabetes including miR-126, C-reactive protein, 2-aminoadipic acid and betatrophin.
Conclusion: The most promising research avenue identified is the detection and quantification of micro RNA. Further, the utilisation of functionalised electrodes as a means to detect biomarker compounds also warrants attention. 相似文献