scholarly journals Cerebrospinal Fluid Pulsation Stress Promotes the Angiogenesis of Tissue-Engineered Laminae

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Linli Li ◽  
Yiqun He ◽  
Han Tang ◽  
Wei Mao ◽  
Haofei Ni ◽  
...  

Background. Angiogenesis is a prerequisite step to achieve the success of bone regeneration by tissue engineering technology. Previous studies have shown the role of cerebrospinal fluid pulsation (CSFP) stress in the reconstruction of tissue-engineered laminae. In this study, we investigated the role of CSFP stress in the angiogenesis of tissue-engineered laminae. Methods. For the in vitro study, a CSFP bioreactor was used to investigate the impact of CSFP stress on the osteogenic mesenchymal stem cells (MSCs). For the in vivo study, forty-eight New Zealand rabbits were randomly divided into the CSFP group and the Non-CSFP group. Tissue-engineered laminae (TEL) was made by hydroxyapatite-collagen I scaffold and osteogenic MSCs and then implanted into the lamina defect in the two groups. The angiogenic and osteogenic abilities of newborn laminae were examined with histological staining, qRT-PCR, and radiological analysis. Results. The in vitro study showed that CSFP stress could promote the vascular endothelial growth factor A (VEGF-A) expression levels of osteogenic MSCs. In the animal study, the expression levels of angiogenic markers in the CSFP group were higher than those in the Non-CSFP group; moreover, in the CSFP group, their expression levels on the dura mater surface, which are closer to the CSFP stress stimulation, were also higher than those on the paraspinal muscle surface. The expression levels of osteogenic markers in the CSFP group were also higher than those in the Non-CSFP group. Conclusion. CSFP stress could promote the angiogenic ability of osteogenic MSCs and thus promote the angiogenesis of tissue-engineered laminae. The pretreatment of osteogenic MSC with a CSFP bioreactor may have important implications for vertebral lamina reconstruction with a tissue engineering technique.

2019 ◽  
Vol 20 (11) ◽  
pp. 2675 ◽  
Author(s):  
Nicholas Wilson ◽  
Robert Steadman ◽  
Ilaria Muller ◽  
Mohd Draman ◽  
D. Aled Rees ◽  
...  

Hyaluronan (HA), an extra-cellular matrix glycosaminoglycan, may play a role in mesenchymal stem cell differentiation to fat but results using murine models and cell lines are conflicting. Our previous data, illustrating decreased HA production during human adipogenesis, suggested an inhibitory role. We have investigated the role of HA in adipogenesis and fat accumulation using human primary subcutaneous preadipocyte/fibroblasts (PFs, n = 12) and subjects of varying body mass index (BMI). The impact of HA on peroxisome proliferator-activated receptor gamma (PPARγ) expression was analysed following siRNA knockdown or HA synthase (HAS)1 and HAS2 overexpression. PFs were cultured in complete or adipogenic medium (ADM) with/without 4-methylumbelliferone (4-MU = HA synthesis inhibitor). Adipogenesis was evaluated using oil red O (ORO), counting adipogenic foci, and measurement of a terminal differentiation marker. Modulating HA production by HAS2 knockdown or overexpression increased (16%, p < 0.04) or decreased (30%, p = 0.01) PPARγ transcripts respectively. The inhibition of HA by 4-MU significantly enhanced ADM-induced adipogenesis with 1.52 ± 0.18- (ORO), 4.09 ± 0.63- (foci) and 2.6 ± 0.21-(marker)-fold increases compared with the controls, also increased PPARγ protein expression (40%, (p < 0.04)). In human subjects, circulating HA correlated negatively with BMI and triglycerides (r = −0.396 (p = 0.002), r = −0.269 (p = 0.038), respectively), confirming an inhibitory role of HA in human adipogenesis. Thus, enhancing HA action may provide a therapeutic target in obesity.


Blood ◽  
2020 ◽  
Vol 136 (4) ◽  
pp. 501-515 ◽  
Author(s):  
Kunpeng Wu ◽  
Yan Yuan ◽  
Huihui Yu ◽  
Xin Dai ◽  
Shu Wang ◽  
...  

Abstract The diversity of the human microbiome heralds the difference of the impact that gut microbial metabolites exert on allogenic graft-versus-host (GVH) disease (GVHD), even though short-chain fatty acids and indole were demonstrated to reduce its severity. In this study, we dissected the role of choline-metabolized trimethylamine N-oxide (TMAO) in the GVHD process. Either TMAO or a high-choline diet enhanced the allogenic GVH reaction, whereas the analog of choline, 3,3-dimethyl-1-butanol reversed TMAO-induced GVHD severity. Interestingly, TMAO-induced alloreactive T-cell proliferation and differentiation into T-helper (Th) subtypes was seen in GVHD mice but not in in vitro cultures. We thus investigated the role of macrophage polarization, which was absent from the in vitro culture system. F4/80+CD11b+CD16/32+ M1 macrophage and signature genes, IL-1β, IL-6, TNF-α, CXCL9, and CXCL10, were increased in TMAO-induced GVHD tissues and in TMAO-cultured bone marrow–derived macrophages (BMDMs). Inhibition of the NLRP3 inflammasome reversed TMAO-stimulated M1 features, indicating that NLRP3 is the key proteolytic activator involved in the macrophage’s response to TMAO stimulation. Consistently, mitochondrial reactive oxygen species and enhanced NF-κB nuclear relocalization were investigated in TMAO-stimulated BMDMs. In vivo depletion of NLRP3 in GVHD recipients not only blocked M1 polarization but also reversed GVHD severity in the presence of TMAO treatment. In conclusion, our data revealed that TMAO-induced GVHD progression resulted from Th1 and Th17 differentiation, which is mediated by the polarized M1 macrophage requiring NLRP3 inflammasome activation. It provides the link among the host choline diet, microbial metabolites, and GVH reaction, shedding light on alleviating GVHD by controlling choline intake.


2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Qing Xia ◽  
Tao Han ◽  
Pinghua Yang ◽  
Ruoyu Wang ◽  
Hengyu Li ◽  
...  

Background. MicroRNAs (miRNAs) play a critical role in the regulation of cancer stem cells (CSCs). However, the role of miRNAs in liver CSCs has not been fully elucidated. Methods. Real-time PCR was used to detect the expression of miR-miR-28-5p in liver cancer stem cells (CSCs). The impact of miR-28-5p on liver CSC expansion was investigated both in vivo and in vitro. The correlation between miR-28-5p expression and sorafenib benefits in HCC was further evaluated in patient-derived xenografts (PDXs). Results. Our data showed that miR-28-5p was downregulated in sorted EpCAM- and CD24-positive liver CSCs. Biofunctional investigations revealed that knockdown miR-28-5p promoted liver CSC self-renewal and tumorigenesis. Consistently, miR-28-5p overexpression inhibited liver CSC’s self-renewal and tumorigenesis. Mechanistically, we found that insulin-like growth factor-1 (IGF-1) was a direct target of miR-28-5p in liver CSCs, and the effects of miR-28-5p on liver CSC’s self-renewal and tumorigenesis were dependent on IGF-1. The correlation between miR-28-5p and IGF-1 was confirmed in human HCC tissues. Furthermore, the miR-28-5p knockdown HCC cells were more sensitive to sorafenib treatment. Analysis of patient-derived xenografts (PDXs) further demonstrated that the miR-28-5p may predict sorafenib benefits in HCC patients. Conclusion. Our findings revealed the crucial role of the miR-28-5p in liver CSC expansion and sorafenib response, rendering miR-28-5p an optimal therapeutic target for HCC.


Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 2891
Author(s):  
Pilar Simmons ◽  
Taylor McElroy ◽  
Antiño R. Allen

Artificial extracellular matrices (aECMs) are an extension of biomaterials that were developed as in-vitro model environments for tissue cells that mimic the native in vivo target tissues’ structure. This bibliometric analysis evaluated the research productivity regarding aECM based on tissue engineering technology. The Web of Science citation index was examined for articles published from 1990 through 2019 using three distinct aECM-related topic sets. Data were also visualized using network analyses (VOSviewer). Terms related to in-vitro, scaffolds, collagen, hydrogels, and differentiation were reoccurring in the aECM-related literature over time. Publications with terms related to a clinical direction (wound healing, stem cells, artificial skin, in-vivo, and bone regeneration) have steadily increased, as have the number of countries and institutions involved in the artificial extracellular matrix. As progress with 3D scaffolds continues to advance, it will become the most promising technology to provide a therapeutic option to repair or replace damaged tissue.


Blood ◽  
2003 ◽  
Vol 101 (5) ◽  
pp. 1759-1768 ◽  
Author(s):  
Bernhard Schiedlmeier ◽  
Hannes Klump ◽  
Elke Will ◽  
Gökhan Arman-Kalcek ◽  
Zhixiong Li ◽  
...  

Ectopic retroviral expression of homeobox B4 (HOXB4) causes an accelerated and enhanced regeneration of murine hematopoietic stem cells (HSCs) and is not known to compromise any program of lineage differentiation. However, HOXB4 expression levels for expansion of human stem cells have still to be established. To test the proposed hypothesis that HOXB4 could become a prime tool for in vivo expansion of genetically modified human HSCs, we retrovirally overexpressed HOXB4 in purified cord blood (CB) CD34+ cells together with green fluorescent protein (GFP) as a reporter protein, and evaluated the impact of ectopic HOXB4 expression on proliferation and differentiation in vitro and in vivo. When injected separately into nonobese diabetic–severe combined immunodeficient (NOD/SCID) mice or in competition with control vector–transduced cells, HOXB4-overexpressing cord blood CD34+ cells had a selective growth advantage in vivo, which resulted in a marked enhancement of the primitive CD34+ subpopulation (P = .01). However, high HOXB4 expression substantially impaired the myeloerythroid differentiation program, and this was reflected in a severe reduction of erythroid and myeloid progenitors in vitro (P < .03) and in vivo (P = .01). Furthermore, HOXB4 overexpression also significantly reduced B-cell output (P < .01). These results show for the first time unwanted side effects of ectopic HOXB4 expression and therefore underscore the need to carefully determine the therapeutic window of HOXB4 expression levels before initializing clinical trials.


2020 ◽  
Author(s):  
Montserrat Lara-Velazquez ◽  
Natanael Zarco ◽  
Anna Carrano ◽  
Jordan Phillipps ◽  
Emily S Norton ◽  
...  

Abstract Background Glioblastomas (GBMs) are the most common primary brains tumors in adults with almost 100% recurrence rate. Patients with lateral ventricle proximal GBMs (LV-GBMs) exhibit worse survival compared to distal locations for reasons that remain unknown. One potential explanation is the proximity of these tumors to the cerebrospinal fluid (CSF) and its contained chemical cues that can regulate cellular migration and differentiation. We therefore investigated the role of CSF on GBM gene expression and the role of a CSF-induced gene, SERPINA3, in GBM malignancy in vitro and in vivo. Methods We utilized patient-derived CSF and primary cultures of GBM brain tumor initiating cells (BTICs). We determined the impact of SERPINA3 expression in glioma patients using TCGA database. SERPINA3 expression changes were evaluated at both the mRNA and protein levels. The effects of knockdown (KD) and overexpression (OE) of SERPINA3 on cell behavior were evaluated by transwell assay (for cell migration), and alamar blue and Ki67 (for viability and proliferation respectively). Stem cell characteristics on KD cells were evaluated by differentiation and colony formation experiments. Tumor growth was studied by intracranial and flank injections. Results GBM CSF induced a significant increase in BTIC migration accompanied by upregulation of the SERPINA3 gene. In patient samples and TCGA data we observed SERPINA3 to correlate directly with brain tumor grade and indirectly with GBM patient survival. Silencing of SERPINA3 induced a decrease in cell proliferation, migration, invasion, and stem cell characteristics, while SERPINA3 overexpression increased cell migration. In vivo, mice orthotopically-injected with SERPINA3 KD BTICs showed increased survival. Conclusions SERPINA3 plays a key role in GBM malignancy and its inhibition results in a better outcome using GBM preclinical models.


2010 ◽  
Vol 23 (7) ◽  
pp. 962-976 ◽  
Author(s):  
Stephanie A. Gardiner ◽  
Jayanand Boddu ◽  
Franz Berthiller ◽  
Christian Hametner ◽  
Robert M. Stupar ◽  
...  

Trichothecenes are a major group of toxins produced by phytopathogenic fungi, including Fusarium graminearum. Trichothecenes inhibit protein synthesis in eukaryotic cells and are toxicologically relevant mycotoxins for humans and animals. Because they promote plant disease, the role of host responses to trichothecene accumulation is considered to be an important aspect of plant defense and resistance to fungal infection. Our overall objective was to examine the barley response to application of the type B trichothecene deoxynivalenol (DON). We found that DON is diluted by movement from the application site to acropetal and basipetal florets. A susceptible barley genotype converted DON to DON-3-O-glucoside, indicating that UDP-glucosyltransferases capable of detoxifying DON must exist in barley. RNA profiling of DON-treated barley spikes revealed strong upregulation of gene transcripts encoding ABC transporters, UDP-glucosyltransferases, cytochrome P450s, and glutathione-S-transferases. We noted that transcripts encoding cysteine synthases were dramatically induced by DON, and that toxin-sensitive yeast on glutathione- or cysteine-supplemented media or carrying a gene that encodes a cysteine biosynthetic enzyme exhibit DON resistance, suggesting that preventing glutathione depletion by increasing cysteine supply could play a role in ameliorating the impact of DON. Evidence for nonenzymatic formation of DON-glutathione adducts in vitro was found using both liquid chromatography–mass spectrometry and nuclear magnetic resonance analysis, indicating that the formation of DON-glutathione conjugates in vivo may reduce the impact of trichothecenes. Our results indicate that barley exhibits multiple defense mechanisms against trichothecenes.


Obesity Facts ◽  
2022 ◽  
Author(s):  
Nadien AbouHashem ◽  
Roan E. Zaied ◽  
Kholoud Al-Shafai ◽  
Mariam Nofal ◽  
Najeeb Syed ◽  
...  

Introduction: Monogenic obesity (MO) is a rare genetic disease characterized by severe early-onset obesity in affected individuals. Previous genetic studies revealed 8 definitive genes for monogenic non-syndromic obesity; many were discovered in consanguineous populations. Here, we examined MO in the Qatari population, whose population is largely consanguineous (54%) and characterized by extensive obesity (45%). Methods: Whole genome sequences of Qatar Biobank samples from 250 subjects with obesity and 250 subjects with normal weight, obtained in association with the Qatar Genome Programme, were searched for genetic variants in the genes known to be associated with MO (i.e., LEP, LEPR, POMC, PCSK1, MC3R, MC4R, MRAP2 and ADCY3). The impact of the variants identified was investigated utilizing in silico tools for prediction in combination with protein visualization by PyMOL. Results: We identified potential MO variants in more than 5% of the cases in our cohort. We revealed 11 rare variants in 6 of the genes targeted, including two disease-causing variants in MC4R and MRAP2, all of which were heterozygous. Moreover, enrichment of a heterozygous ADCY3 variant (c.1658C>T; p.A553V) appeared to cause severe obesity in an autosomal dominant manner. Conclusion: These findings highlight the importance of implementing routine testing for genetic variants that predispose for MO in Qatar. Clearly, additional studies of this nature on populations not yet examined are required. At the same time, functional investigations, both in vitro and in vivo, are necessary in order to better understand the role of the variants identified in the pathogenesis of obesity.


2020 ◽  
Vol 26 (4) ◽  
pp. 240-255
Author(s):  
Yongpei He ◽  
Ting Xiong ◽  
Fang Guo ◽  
Zhenzhen Du ◽  
Yixian Fan ◽  
...  

Abstract Endometriosis is a gynecological disease with abnormal expression of interleukin (IL)-37 which can suppress inflammation and the immune system. Here we investigated the role of the IL-37b splice variant in endometriosis in vivo and in vitro. In a murine model of endometriosis, in vivo administration of IL-37b significantly inhibited the development of lesions judged by the number (P = 0.0213), size (P = 0.0130) and weight (P = 0.0152) of lesions. IL-37b had no effect on the early stage of lesion formation, however administration in the growth stage of lesions decreased the number (P = 0.0158), size (P = 0.0158) and weight (P = 0.0258) of lesions compared with PBS control, an effect that was not reversed by macrophage depletion. Expressions of inflammatory factors, matrix metalloproteinases and vascular endothelial growth factor-A mRNA/protein were significantly inhibited in ectopic lesions following IL-37b administration, and in uterine segments treated in vitro. In vitro treatment of uterine segments with IL-37b inhibited phosphorylation of Akt and Erk1/2 in uterine segments. Isolated mouse endometrial stromal treated with IL-37b and transfected with pIL-37b plasmid got suppressed cell proliferation, invasion, angiogenesis and the expression of inflammatory factors. In addition, transfection with pIL-37b significantly decreased the phosphorylation of Akt and Erk1/2. IL-37b also inhibited proliferation and the expression of inflammatory and angiogenesis factors in epithelial cell line RL95–2. These findings suggest that IL-37b may inhibit the growth of lesions by regulating proliferation, invasion, angiogenesis and inflammation through Akt and Erk1/2 signaling pathway.


1997 ◽  
Vol 16 (11) ◽  
pp. 629-635 ◽  
Author(s):  
AP Moghaddam ◽  
R. Abbas ◽  
JW Fisher ◽  
JC Lipscomb

1 Both trichloroethylene and its metabolite, dichloroa cetic acid, produce liver tumors peroxisome prolifera tion and other adverse cellular alterations in rodents. 2 The hepatic mechanism by which dichloroacetic acid is formed is not conclusively demonstrated, but pharmacokinetic models have successfully associated its formation with trichloroacetic acid as immediate precursor. 3 Previous investigations have shown that dichloroace tic acid is formed from trichloroacetic acid by gut microflora isolated in vitro. 4 To determine the impact of gut microflora on dichlor oacetic acid formation from a trichloroethylene dose in vivo, we developed a procedure which reduced gut microflora some 3 orders of magnitude below pub lished levels. 5 The administration of trichloroethylene to control mice and to mice whose gut was practically sterile resulted in equivalent concentrations of dichloroace tic acid and other metabolites in blood and liver, but significantly different content of these metabolites in cecum contents. 6 These data indicate that gut microflora contribute minimally, if at all, to the formation of circulating dichloroacetic acid under these conditions.


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