Non-neuronal cells inhibit catecholaminergic differentiation of primary sensory neurons: role of leukemia inhibitory factor

Development ◽  
1993 ◽  
Vol 118 (1) ◽  
pp. 83-93 ◽  
Author(s):  
G. Fan ◽  
D.M. Katz

Although some sensory ganglion cells in mature animals are catecholaminergic, most mammalian sensory neurons that express the catecholamine-synthesizing enzyme tyrosine hydroxylase (TH) do so only transiently during early gangliogenesis in vivo. The lack of TH expression at later stages appears to be due to modulation of this catecholaminergic potential. A previous study showed that the phenotype reappears, for example, when E16.5 and older sensory ganglia are dissociated in culture into single cells, suggesting that extracellular influences can modulate TH expression. Moreover, TH expression in dissociate cultures is cell-density dependent, as a four-fold increase in plating density led to a 30% decrease in the percentage of TH neurons. The present study demonstrates that inhibition of TH expression in high density cultures is mediated by ganglionic non-neuronal cells (NNC), as removal of NNC abolished density-dependent inhibition. Moreover, plating E16.5 trigeminal neurons at low density on top of NNC monolayers resulted in an 85% decrease in the percentage of TH neurons. Treatment of cultures with non-neuronal cell conditioned medium (NNC-CM) reproduced the effect of coculture with NNC, suggesting that diffusible factors from NNC were involved in the inhibition of TH. The inhibitory effect of NNC-CM was mimicked by treatment of dissociate cultures with ciliary neurotrophic factor (CNTF) and leukemia inhibitory factor (LIF). However, immunoprecipitation of NNC-CM with antibodies against LIF or CNTF showed that only anti-LIF antibodies were able partially to remove the TH inhibitory activity of NNC-CM. Therefore, LIF is one, but not the only, factor mediating NNC inhibition of TH expression in cultured sensory neurons. In summary, these data indicate that ganglionic NNC can regulate sensory transmitter phenotype in culture by inhibiting expression of specific molecular traits. The finding that LIF can partially account for the inhibitory effect of ganglionic NNC on TH expression suggests a novel role for this cytokine in regulating differentiation of catecholaminergic properties in sensory neurons.

Pharmaceutics ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 397
Author(s):  
Yoo-Kyung Song ◽  
Jin-Ha Yoon ◽  
Jong Kyu Woo ◽  
Ju-Hee Kang ◽  
Kyeong-Ryoon Lee ◽  
...  

The potential inhibitory effect of quercetin, a major plant flavonol, on breast cancer resistance protein (BCRP) activity was investigated in this study. The presence of quercetin significantly increased the cellular accumulation and associated cytotoxicity of the BCRP substrate mitoxantrone in human cervical cancer cells (HeLa cells) in a concentration-dependent manner. The transcellular efflux of prazosin, a stereotypical BCRP substrate, was also significantly reduced in the presence of quercetin in a bidirectional transport assay using human BCRP-overexpressing cells; further kinetic analysis revealed IC50 and Ki values of 4.22 and 3.91 μM, respectively. Moreover, pretreatment with 10 mg/kg quercetin in rats led to a 1.8-fold and 1.5-fold increase in the AUC8h (i.e., 44.5 ± 11.8 min∙μg/mL vs. 25.7 ± 9.98 min∙μg/mL, p < 0.05) and Cmax (i.e., 179 ± 23.0 ng/mL vs. 122 ± 23.2 ng/mL, p < 0.05) of orally administered sulfasalazine, respectively. Collectively, these results provide evidence that quercetin acts as an in vivo as well as in vitro inhibitor of BCRP. Considering the high dietary intake of quercetin as well as its consumption as a dietary supplement, issuing a caution regarding its food–drug interactions should be considered.


1994 ◽  
Vol 161 (2) ◽  
pp. 338-344 ◽  
Author(s):  
Catherine D. Thaler ◽  
Leigh Suhr ◽  
Nancy Ip ◽  
David M. Katz

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 779-779
Author(s):  
Maegan L. Capitano ◽  
Nirit Mor-Vaknin ◽  
Maureen Legendre ◽  
Scott Cooper ◽  
David Markovitz ◽  
...  

Abstract DEK is a nuclear DNA-binding protein that has been implicated in the regulation of transcription, chromatin remodeling, and mRNA processing. Endogenous DEK regulates hematopoiesis, as BM from DEK-/- mice manifest increased hematopoietic progenitor cell (HPC) numbers and cycling status and decreased long-term and secondary hematopoietic stem cell (HSC) engrafting capability (Broxmeyer et al., 2012, Stem Cells Dev., 21: 1449; 2013, Stem Cells, 31: 1447). Moreover, recombinant mouse (rm) DEK inhibits HPC colony formation in vitro. We now show that rmDEK is myelosuppressive in vitro in an S-phase specific manner and reversibly decreases numbers (~2 fold) and cycling status of CFU-GM, BFU-E, and CFU-GEMM in vivo, with DEK-/- mice being more sensitive than control mice to this suppression. In contrast, in vivo administration of rmDEK to wild type and DEK-/- mice enhanced numbers of phenotypic LT-HSC. This suggests that DEK may enhance HSC numbers by blocking production of HPCs. We thus assessed effects of DEK on ex vivo expansion of human CD34+ cord blood (CB) and mouse Lin- BM cells stimulated with SCF, Flt3 ligand, and TPO. DEK significantly enhanced ex vivo expansion of rigorously-defined HSC by ~3 fold both on day 4 (~15 fold increase from day 0) and 7 (~29 fold increase from day 0) when compared to cells expanded without DEK. Expanding HSC with DEK also resulted in a decrease in the percentage of apoptotic HSC. Further studies were done to better define how DEK works on HSC and HPC. As extracellular DEK can bind to heparan sulfate proteoglycans (HSPG), become internalized, and then remodel chromatin in non-hematopoietic cells in vitro (Kappes et al., 2011, Genes Dev., 673; Saha et al., 2013, PNAS, 110: 6847), we assessed effects of DEK on the heterochromatin marker H3K9He3 in the nucleus of purified mouse lineage negative, Sca-1 positive, c-Kit positive (LSK) BM cells by imaging flow cytometry. DEK enhanced the presence of H3K9Me3 in the nucleus of DEK-/- LSK cells, indicating that rmDEK can be internalized by LSK cells and mediate heterochromatin formation. We also investigated whether inhibiting DEK's ability to bind to HSPG would block the inhibitory function of DEK in HPC. Blocking the synthesis of, the surface expression of, and the binding capability of HSPG blocked the inhibitory effect of DEK on colony formation. Blocking the ability of DEK to bind to HSPG also blocks the expansion of HSC in ex vivo expansion assays, suggesting that DEK mediates its function in both HSC and HPC by binding to HSPG but with opposing effects. To further evaluate the biological role of rmDEK, we utilized single-stranded anti-DEK aptamers that inactivate its function. These aptamers, but not their control, neutralized the inhibitory effect of rmDEK on HPC colony formation. Moreover, treating BM cells in vitro with truncated rmDEK created by incubating DEK with the enzyme DPP4 (DEK has targeted truncation sites for DPP4) eliminated the inhibitory effects of DEK, suggesting that DEK must be in its full- length form in order to perform its function. Upon finding that DEK has a Glu-Leu-Arg (ELR) motif, similar to that of CXC chemokines such as IL-8, and as DEK is a chemoattractant for mature white blood cells, we hypothesized that DEK may manifest at least some of its actions through CXCR2, the receptor known to bind and mediate the actions of IL-8 and MIP-2. In order to examine if this is indeed the case, we first confirmed expression of CXCR2 on the surface of HSC and HPC and then determined if neutralizing CXCR2 could block DEK's inhibitory function in HPC. BM treated in vitro with rmDEK, rhIL-8, or rmMIP-2 inhibited colony formation; pretreating BM with neutralizing CXCR2 antibodies blocked the inhibitory effect of these proteins. DEK inhibition of CFU-GM colony formation is dependent on Gai-protein-coupled receptor signaling as determined through the use of pertussis toxin, which is a mechanism unique to DEK, as we have previously reported that IL-8 and MIP-1a are insensitive to the inhibitory effects of pertussis toxin. Blocking the ability of DEK to bind to CXCR2 also inhibited the expansion of HSC in an ex vivo expansion assay. This suggests that DEK binds to CXCR2, HSPG or both to mediate its function on HPC and HSC, enhancing HSC but decreasing HPC numbers. Therefore, DEK may be a crucial regulatory determinant of HSC/HPC function and fate decision that is utilized to enhance ex vivo expansion of HSC. Disclosures No relevant conflicts of interest to declare.


Endocrinology ◽  
1993 ◽  
Vol 132 (3) ◽  
pp. 1359-1366 ◽  
Author(s):  
J Cornish ◽  
K Callon ◽  
A King ◽  
S Edgar ◽  
I R Reid

Blood ◽  
1991 ◽  
Vol 78 (7) ◽  
pp. 1685-1691
Author(s):  
Y Kletter ◽  
I Riklis ◽  
I Shalit ◽  
I Fabian

We analyzed the effect of ciprofloxacin, fleroxacin, and ceftazidime on production of colony-stimulating factors (CSF) by cultured murine spleen cells in the presence of pokeweed mitogen (PWM). Ciprofloxacin at concentrations of 5 to 10 micrograms/mL in concert with PWM stimulated CSF production by cultured spleen cells. A 3.5-fold increase in the number of CFU-C was observed in the presence of ciprofloxacin- PWM spleen conditioned medium (SCM) as compared with control cultures exposed to PWM-SCM only. Antimurine GM-CSF and antimurine interleukin-3 (IL-3) antibodies inhibited colony formation stimulated by PWM-SCM or ciprofloxacin-PWM-SCM. Fleroxacin and ceftazidime at concentrations of 1 to 100 micrograms/mL and ciprofloxacin at high concentration (greater than 10 micrograms/mL) either did not affect CSF production by spleen cells or had an inhibitory effect. In vivo treatment of sublethally irradiated (650 rad) mice with ciprofloxacin (15 mg/kg per dose three times daily for 5 days) resulted in an increased number of myeloid progenitors in the spleen and bone marrow (BM) of treated mice. In contrast, treatment with ceftazidime did not affect progenitor cell numbers. On days 4 and 8 postirradiation ciprofloxacin-treated mice had a 2.3- and 3.8-fold increase, respectively, in the number of CFU-C in the BM. The number of CFU-C in the spleen did not increase on day 4 postirradiation, but on day 8, the number increased 1.7-fold. On day 4 postirradiation, sublethally irradiated mice treated with ciprofloxacin had a higher WBC count, RBC count, and hemoglobin level as compared with ceftazidime- and saline-treated mice. Twenty-four days postirradiation, 45% of saline-treated mice (20 of 44), and 35% of ceftazidime-treated mice (8 of 23) died, as compared with 13% (5 of 38) of ciprofloxacin-treated mice (P less than .05). These studies indicate that ciprofloxacin may have an immune-enhancing effect on the hematopoietic system in neutropenic mice.


Blood ◽  
1996 ◽  
Vol 87 (11) ◽  
pp. 4618-4628 ◽  
Author(s):  
SJ Szilvassy ◽  
KP Weller ◽  
W Lin ◽  
AK Sharma ◽  
AS Ho ◽  
...  

Attempts to maintain or expand primitive hematopoietic stem cells in vitro without the concomitant loss of their differentiative and proliferative potential in vivo have largely been unsuccessful. To investigate this problem, we compared the ability of three cloned bone marrow (BM) stromal cell lines to support the growth of primitive Thy- 1lo Sca-1+H-2Khi cells isolated by fluorescence-activated cell sorting from the BM of Ly-5.2 mice treated 1 day previously with 5-fluo- rouracil. Sorted cells were highly enriched in cobblestone area-forming cells (CAFC), but their frequency was dependent on the stromal cell lines used in this assay (1 per 45 cells on SyS-1; 1 per 97 cells on PA6). In the presence of recombinant leukemia inhibitory factor (LIF), CAFC cloning efficiency was increased to 1 per 8 cells on SyS-1 and 1 per 11 cells on PA6, thus showing the high clonogenicity of this primitive stem cell population. More primitive stem cells with competitive repopulating potential were measured by injecting the sorted cells into lethally irradiated Ly-5.1 mice together with 10(5) radioprotective Ly-5.1 BM cells whose long-term repopulating ability has been “compromised” by two previous cycles of marrow transplantation and regeneration. Donor-derived lymphocytes and granulocytes were detected in 66% of animals injected with 50 sorted cells. To quantitate the maintenance of competitive repopulating units (CRU) by stromal cells, sorted cells were transplanted at limiting dilution before and after being cultured for 2 weeks on adherent layers of SyS-1, PA6, or S17 cells. CRU represented 1 per 55 freshly sorted cells. CRU could be recovered from cocultures supported by all three stromal cell lines, but their numbers were approximately-sevenfold less than on day 0. In contrast, the addition of LIF to stromal cultures improved CRU survival by 2.5-fold on S17 and PA6 cells (approximately two-fold to threefold decline), and enabled their maintenance on SyS-1. LIF appeared to act indirectly, because alone it did not support the proliferation of Thy- 1lo Sca-1+H-2Khi cells in stroma-free cultures. Polymerase chain reaction (RT-PCR) analysis revealed that Interleukin-1beta (IL-1 beta) IL-2, IL-6, granulocyte-colony stimulating factor, granulocyte macrophage-colony stimulating factor, transforming growth factors, LIF, and Steel Factor (SLF) mRNAs were upregulated in SyS-1 within 1 to 6 hours of LIF-stimulation. To determine if increased expression of SLF by LIF-stimulated SyS-1 cells could account for their capacity to support stem cells, sorted calls were cocultured on simian CV-E cells that were transfected with an expression vector encoding membrane-bound SLF, or supplemented with soluble SLF. In both cases, SLF synergized with IL-6 produced endogenously by CV-E cells enabling CAFC growth equivalent to that on LIF-stimulated SyS-1. CAFC development on LIF- stimulated SyS-1 could also be completely abrogated by an anti-SLF antibody. These data provide evidence for a role of LIF in the support of long-term repopulating stem cells by indirectly promoting cytokine expression by BM stroma. Furthermore, we have used quantitative assays to show a maintenance of CRU numbers, with retention of in vivo function following ex vivo culture.


2021 ◽  
Author(s):  
Jialong Qi ◽  
Tao Wang ◽  
Zhidong Zhang ◽  
Zongsheng Yin ◽  
Yiming Liu ◽  
...  

Study design: Spinal cord injury (SCI) rat model and cell model were established for in vivo and in vitro experiments. Functional assays were utilized to explore the role of the circRNAs derived from catenin beta 1 (mmu_circ_0001859, circ-Ctnnb1 herein) in regulating neuronal cell viability and apoptosis. Bioinformatics analysis and mechanism experiments were conducted to assess the underlying molecular mechanism of circ-Ctnnb1. Objective: We aimed to probe into the biological function of circ-Ctnnb1 in neuronal cells of SCI. Methods: The rat model of SCI and hypoxia-induced cell model were constructed to examine circ-Ctnnb1 expression in SCI through quantitative reverse transcription real-time polymerase chain reaction (RT-qPCR). Basso, Beattie and Bresnahan (BBB) score was utilized for evaluating the neurological function. Terminal-deoxynucleoitidyl Transferase Mediated Nick End labeling (TUNEL) assays were performed to assess the apoptosis of neuronal cells. RNase R and Actinomycin D (ActD) were used to treat cells to evaluate the stability of circ-Ctnnb1. Results: Circ-Ctnnb1 was highly expressed in SCI rat models and hypoxia-induced neuronal cells, and its deletion elevated the apoptosis rate of hypoxia-induced neuronal cells. Furthermore, circ-Ctnnb1 activated the Wnt/β-catenin signaling pathway via sponging mircoRNA-205-5p (miR-205-5p) to up-regulate Ctnnb1 and Wnt family member 2B (Wnt2b). Conclusion: Circ-Ctnnb1 promotes SCI through regulating Wnt/β-catenin signaling via modulating the miR-205-5p/Ctnnb1/Wnt2b axis.


1995 ◽  
Vol 108 (1) ◽  
pp. 73-83 ◽  
Author(s):  
M.S. Pepper ◽  
N. Ferrara ◽  
L. Orci ◽  
R. Montesano

Using an in vitro model in which endothelial cells can be induced to invade a three-dimensional collagen gel to form capillary-like tubular structures, we demonstrate that leukemia inhibitory factor (LIF) inhibits angiogenesis in vitro. The inhibitory effect was observed on both bovine aortic endothelial (BAE) and bovine microvascular endothelial (BME) cell, and occurred irrespective of the angiogenic stimulus, which included basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), the synergistic effect of the two in combination, or the tumor promoter phorbol myristate acetate. LIF inhibited bFGF- and VEGF-induced proliferation in BAE and BME cells. In addition, LIF inhibited BAE but not BME cell migration in a conventional two-dimensional assay. Finally, LIF decreased the proteolytic activity of BAE and BME cells and increased their expression of plasminogen activator inhibitor-1. These results demonstrate that LIF inhibits angiogenesis in vitro, an effect that can be correlated with a LIF-mediated decrease in endothelial cell proliferation, migration and extracellular proteolysis.


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