scholarly journals Insulin is essential for in vitro chondrogenesis of mesenchymal progenitor cells and influences chondrogenesis in a dose-dependent manner

2012 ◽  
Vol 37 (1) ◽  
pp. 153-158 ◽  
Author(s):  
Michael B. Mueller ◽  
Torsten Blunk ◽  
Bernhard Appel ◽  
Angelika Maschke ◽  
Achim Goepferich ◽  
...  
2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Ai-Ting Yang ◽  
Dou-Dou Hu ◽  
Ping Wang ◽  
Min Cong ◽  
Tian-Hui Liu ◽  
...  

Transforming growth factor-beta 1 (TGF-β1) plays a central role in hepatic progenitor cells- (HPCs-) mediated liver repair and fibrosis. However, different effects of TGF-β1 on progenitor cells have not been described. In this study, both in vitro (HPCs cocultured with hepatic stellate cells (HSCs) in transwells) and in vivo (CCl4-injured liver fibrosis rat) systems were used to evaluate the impacts. We found that HPCs pretreated with TGF-β1 for 12 hours inhibited the activation of HSCs, while sensitization for 48 hours increased the activation of HSCs. Consistent with these in vitro results, the in vivo fibrosis rat model showed the same time-dependent dual effect of TGF-β1. Regression of liver fibrosis as well as normalization of serum aminotransferase and albumin levels was detected in the rats transplanted with HPCs pretreated with TGF-β1 for 12 hours. In contrast, severe liver fibrosis and elevated collagen-1 levels were detected in the rats transplanted with HPCs pretreated with TGF-β1 for 48 hours. Furthermore, the TGF-β1-pretreated HPCs were shown to deactivate HSCs via enhancing SERPINE1 expression. Inhibition of SERPINE1 reversed the deactivation response in a dose-dependent manner.


Blood ◽  
1997 ◽  
Vol 90 (9) ◽  
pp. 3438-3443 ◽  
Author(s):  
Yumi Umemoto ◽  
Kohichiro Tsuji ◽  
Feng-Chun Yang ◽  
Yasuhiro Ebihara ◽  
Azusa Kaneko ◽  
...  

Abstract Leptin, the product of obese gene, was originally identified as a factor regulating body-weight homeostasis and energy balance. The present study has shown that leptin acts on murine hematopoiesis in vitro. In the culture of bone marrow cells (BMC) of normal mice, leptin induced only granulocyte-macrophage (GM) colony formation in a dose-dependent manner, and no other types of colonies were detected even in the presence of erythropoietin (Epo). Leptin also induced GM colony formation from BMC of db/db mutant mice whose leptin receptors were incomplete, but the responsiveness was significantly reduced. The effect of leptin on GM colony formation from BMC of normal mice was also observed in serum-free culture, and comparable with that of GM-colony–stimulating factor (CSF ). Although leptin alone supported few colonies from BMC of 5-fluorouracil (5-FU)–treated mice in serum-free culture, remarkable synergism between leptin and stem cell factor (SCF ) was obtained in the colony formation. The addition of leptin to SCF enhanced the SCF-dependent GM colony formation and induced the generation of a number of multilineage colonies in the presence of Epo. When lineage (Lin)−Sca-1+ cells sorted from BMC of 5-FU–treated mice were incubated in serum-free culture, leptin synergized with SCF in the formation of blast cell colonies, which efficiently produced secondary colonies including a large proportion of multilineage colonies in the replating experiment. In serum-free cultures of clone-sorted Lin−c-Kit+Sca-1+ and Lin−c-Kit+Sca-1− cells, although synergism of leptin and SCF was observed in the colony formation from both cells, leptin alone induced the colony formation from Lin−c-Kit+Sca-1−, but not Lin−c-Kit+Sca-1+ cells. These results have shown that leptin stimulates the proliferation of murine myelocytic progenitor cells and synergizes with SCF in the proliferation of primitive hematopoietic progenitors in vitro.


Blood ◽  
2004 ◽  
Vol 103 (3) ◽  
pp. 921-926 ◽  
Author(s):  
Ferdinand H. Bahlmann ◽  
Kirsten de Groot ◽  
Jens-Michael Spandau ◽  
Aimee L. Landry ◽  
Barbara Hertel ◽  
...  

AbstractCirculating bone marrow–derived endothelial progenitor cells (EPCs) promote vascular reparative processes and neoangiogenesis, and their number in peripheral blood correlates with endothelial function and cardiovascular risk. We tested the hypothesis that the cytokine erythropoietin (EPO) stimulates EPCs in humans. We studied 11 patients with renal anemia and 4 healthy subjects who received standard doses of recombinant human EPO (rhEPO). Treatment with rhEPO caused a significant mobilization of CD34+/CD45+ circulating progenitor cells in peripheral blood (measured by flow cytometry), and increased the number of functionally active EPCs (measured by in vitro assay) in patients (week 2, 312% ± 31%; week 8, 308% ± 40%; both P < .01 versus baseline) as well as in healthy subjects (week 8, 194% ± 15%; P < .05 versus baseline). The effect on EPCs was already observed with an rhEPO dose of about 30 IU/kg per week. Administration of rhEPO increased the number of functionally active EPCs by differentiation in vitro in a dose-dependent manner, assessed in cell culture and by tube formation assay. Furthermore, rhEPO activates the Akt protein kinase pathway in EPCs. Erythropoietin increases the number of functionally active EPCs in humans. Administration of rhEPO or EPO analogs may open new therapeutic strategies in regenerative cardiovascular medicine.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Yanling Zhao ◽  
Yiying Wu ◽  
Haolu Hu ◽  
Jinghui Cai ◽  
Min Ning ◽  
...  

In animal experiments, hippocampal neurogenesis and the activity of thiamine-dependent transketolase decrease markedly under conditions of thiamine deficiency. To further investigate the effect of thiamine deficiency on the proliferation of hippocampal progenitor cells (HPCs) and the potential mechanisms involved in this effect, we cultured HPCs in vitro in the absence of thiamine and found that proliferation and transketolase activity were both significantly repressed. Furthermore, specific inhibition of transketolase activity by oxythiamine strongly inhibited HPC proliferation in a dose-dependent manner. However, thiamine deficiency itself inhibited the proliferation to a greater degree than did oxythiamine. Taken together, our results suggest that modulation of transketolase activity might be one of the mechanisms by which thiamine regulates the proliferation of hippocampal progenitor cells.


1984 ◽  
Vol 107 (3) ◽  
pp. 395-400 ◽  
Author(s):  
Itaru Kojima ◽  
Etsuro Ogata ◽  
Hiroshi Inano ◽  
Bun-ichi Tamaoki

Abstract. Incubation of 18-hydroxycorticosterone with the sonicated mitochondrial preparation of bovine adrenal glomerulosa tissue leads to the production of aldosterone, as measured by radioimmunoassay. The in vitro production of aldosterone from 18-hydroxycorticosterone requires both molecular oxygen and NADPH, and is inhibited by carbon monoxide. Cytochrome P-450 inhibitors such as metyrapone, SU 8000. SU 10603, SKF 525A, amphenone B and spironolactone decrease the biosynthesis of aldosterone from 18-hydroxycorticosterone. These results support the conclusion that the final reaction in aldosterone synthesis from 18-hydroxycorticosterone is catalyzed by an oxygenase, but not by 18-hydroxysteroid dehydrogenase. By the same preparation, the production of [3H]aldosterone but not [3H]18-hydroxycorticosterone from [1,2-3H ]corticosterone is decreased in a dose-dependent manner by addition of non-radioactive 18-hydroxycorticosterone.


This trial research was performed to discuss the immune-influence of Melaleuca leucadendra ‘paper-bark tree’ dried leaves which is an important medical plant known in many regions in the world. The leaves were dissolved in a mixture of (ethanol + water) (3:1) mixture, then filtered, evaporated and dried under reduced pressure to obtain leaves extract. The macrophages of blood derived origin were provided from rats and mixed with three different leaves extracts doses in tissue culture plates and incubated then stained with fluorescent acridine orange and examined under fluorescent microscope to assess the phagocytic and killing potency. The wells contents were aspirated and assayed for nitric oxide and interleukin-2 levels. The results displayed an obvious increase in phagocytic, killing performance as well as nitric oxide and IL-2 level production than control in a dose dependent manner. The obtained results suggested the immune-stimulant impact of the paper-bark tree leaves.


2001 ◽  
Vol 91 (6) ◽  
pp. 2703-2712 ◽  
Author(s):  
Stephen M. Johnson ◽  
Julia E. R. Wilkerson ◽  
Daniel R. Henderson ◽  
Michael R. Wenninger ◽  
Gordon S. Mitchell

Brain stem preparations from adult turtles were used to determine how bath-applied serotonin (5-HT) alters respiration-related hypoglossal activity in a mature vertebrate. 5-HT (5–20 μM) reversibly decreased integrated burst amplitude by ∼45% ( P < 0.05); burst frequency decreased in a dose-dependent manner with 20 μM abolishing bursts in 9 of 13 preparations ( P < 0.05). These 5-HT-dependent effects were mimicked by application of a 5-HT1A agonist, but not a 5-HT1B agonist, and were abolished by the broad-spectrum 5-HT antagonist, methiothepin. During 5-HT (20 μM) washout, frequency rebounded to levels above the original baseline for 40 min ( P < 0.05) and remained above baseline for 2 h. A 5-HT3 antagonist (tropesitron) blocked the post-5-HT rebound and persistent frequency increase. A 5-HT3 agonist (phenylbiguanide) increased frequency during and after bath application ( P < 0.05). When phenylbiguanide was applied to the brain stem of brain stem/spinal cord preparations, there was a persistent frequency increase ( P < 0.05), but neither spinal-expiratory nor -inspiratory burst amplitude were altered. The 5-HT3receptor-dependent persistent frequency increase represents a unique model of plasticity in vertebrate rhythm generation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Benjamin N. Nelson ◽  
Savannah G. Beakley ◽  
Sierra Posey ◽  
Brittney Conn ◽  
Emma Maritz ◽  
...  

AbstractCryptococcal meningitis is a life-threatening disease among immune compromised individuals that is caused by the opportunistic fungal pathogen Cryptococcus neoformans. Previous studies have shown that the fungus is phagocytosed by dendritic cells (DCs) and trafficked to the lysosome where it is killed by both oxidative and non-oxidative mechanisms. While certain molecules from the lysosome are known to kill or inhibit the growth of C. neoformans, the lysosome is an organelle containing many different proteins and enzymes that are designed to degrade phagocytosed material. We hypothesized that multiple lysosomal components, including cysteine proteases and antimicrobial peptides, could inhibit the growth of C. neoformans. Our study identified the contents of the DC lysosome and examined the anti-cryptococcal properties of different proteins found within the lysosome. Results showed several DC lysosomal proteins affected the growth of C. neoformans in vitro. The proteins that killed or inhibited the fungus did so in a dose-dependent manner. Furthermore, the concentration of protein needed for cryptococcal inhibition was found to be non-cytotoxic to mammalian cells. These data show that many DC lysosomal proteins have antifungal activity and have potential as immune-based therapeutics.


2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Xuxing Shen ◽  
Chao Wu ◽  
Meng Lei ◽  
Qing Yan ◽  
Haoyang Zhang ◽  
...  

AbstractCarfilzomib, a second-generation proteasome inhibitor, has significantly improved the survival rate of multiple myeloma (MM) patients, but its clinical application is still restricted by drug resistance and cardiotoxicity. Here, we identified a novel proteasome inhibitor, D395, and assessed its efficacy in treating MM as well as its cardiotoxicity at the preclinical level. The activities of purified and intracellular proteasomes were measured to determine the effect of D395 on the proteasome. CCK-8 and flow cytometry experiments were designed to evaluate the effects of D395 on cell growth and apoptosis. The effects of D395 and carfilzomib on serum enzyme activity, echocardiography features, cardiomyocyte morphology, and hERG channels were also compared. In our study, D395 was highly cytotoxic to MM cell lines and primary MM cells but not normal cells, and it was well tolerated in vivo. Similar to carfilzomib, D395 inhibited osteoclast differentiation in a dose-dependent manner. In particular, D395 exhibited lower cardiotoxicity than carfilzomib in all experiments. In conclusion, D395 is a novel irreversible proteasome inhibitor that has remarkable anti-MM activity and mild cardiotoxicity in vitro and in vivo.


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