| 5841. |
- Morini, Marco F., et al.
(författare)
-
VE-Cadherin-Mediated Epigenetic Regulation of Endothelial Gene Expression
- 2018
-
Ingår i: Circulation Research. - : LIPPINCOTT WILLIAMS & WILKINS. - 0009-7330 .- 1524-4571. ; 122:2, s. 231-245
-
Tidskriftsartikel (refereegranskat)abstract
- Rationale: The mechanistic foundation of vascular maturation is still largely unknown. Several human pathologies are characterized by deregulated angiogenesis and unstable blood vessels. Solid tumors, for instance, get their nourishment from newly formed structurally abnormal vessels which present wide and irregular interendothelial junctions. Expression and clustering of the main endothelial-specific adherens junction protein, VEC (vascular endothelial cadherin), upregulate genes with key roles in endothelial differentiation and stability.Objective: We aim at understanding the molecular mechanisms through which VEC triggers the expression of a set of genes involved in endothelial differentiation and vascular stabilization.Methods and Results: We compared a VEC-null cell line with the same line reconstituted with VEC wild-type cDNA. VEC expression and clustering upregulated endothelial-specific genes with key roles in vascular stabilization including claudin-5, vascular endothelial-protein tyrosine phosphatase (VE-PTP), and von Willebrand factor (vWf). Mechanistically, VEC exerts this effect by inhibiting polycomb protein activity on the specific gene promoters. This is achieved by preventing nuclear translocation of FoxO1 (Forkhead box protein O1) and beta-catenin, which contribute to PRC2 (polycomb repressive complex-2) binding to promoter regions of claudin-5, VE-PTP, and vWf. VEC/beta-catenin complex also sequesters a core subunit of PRC2 (Ezh2 [enhancer of zeste homolog 2]) at the cell membrane, preventing its nuclear translocation. Inhibition of Ezh2/VEC association increases Ezh2 recruitment to claudin-5, VE-PTP, and vWf promoters, causing gene downregulation. RNA sequencing comparison of VEC-null and VEC-positive cells suggested a more general role of VEC in activating endothelial genes and triggering a vascular stability-related gene expression program. In pathological angiogenesis of human ovarian carcinomas, reduced VEC expression paralleled decreased levels of claudin-5 and VE-PTP.Conclusions: These data extend the knowledge of polycomb-mediated regulation of gene expression to endothelial cell differentiation and vessel maturation. The identified mechanism opens novel therapeutic opportunities to modulate endothelial gene expression and induce vascular normalization through pharmacological inhibition of the polycomb-mediated repression system.
|
|
| 5842. |
- Mormino, Maurizio, 1988, et al.
(författare)
-
Identification of acetic acid sensitive strains through biosensor-based screening of a Saccharomyces cerevisiae CRISPRi library
- 2022
-
Ingår i: Microbial Cell Factories. - : Springer Science and Business Media LLC. - 1475-2859. ; 21:1, s. 214-
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Acetic acid tolerance is crucial for the development of robust cell factories for conversion of lignocellulosic hydrolysates that typically contain high levels of acetic acid. Screening mutants for growth in medium with acetic acid is an attractive way to identify sensitive variants and can provide novel insights into the complex mechanisms regulating the acetic acid stress response. RESULTS: An acetic acid biosensor based on the Saccharomyces cerevisiae transcription factor Haa1, was used to screen a CRISPRi yeast strain library where dCas9-Mxi was set to individually repress each essential or respiratory growth essential gene. Fluorescence-activated cell sorting led to the enrichment of a population of cells with higher acetic acid retention. These cells with higher biosensor signal were demonstrated to be more sensitive to acetic acid. Biosensor-based screening of the CRISPRi library strains enabled identification of strains with increased acetic acid sensitivity: strains with gRNAs targeting TIF34, MSN5, PAP1, COX10 or TRA1. CONCLUSIONS: This study demonstrated that biosensors are valuable tools for screening and monitoring acetic acid tolerance in yeast. Fine-tuning the expression of essential genes can lead to altered acetic acid tolerance.
|
|
| 5843. |
- Morozova-Roche, Ludmilla, et al.
(författare)
-
Calcium-binding lysozymes
- 2012
-
Bok (övrigt vetenskapligt/konstnärligt)abstract
- In this book, the authors describe an important class of calcium binding lysozymes that are evolutionarily related to the lysozyme superfamily and the lactalbumins. The authors take the reader through a journey from the evolution, then the structure and properties of the calcium binding lysozymes. They discuss new unique protein folding pathways with local cooperative, close related folding modes that exhibit multiple folding pathways which are not properties of the lactalbumins or non calcium binding lysozymes. They comprise one of the most diverse group of examples in protein folding. In addition this protein class, especially equine lysozyme, shows peculiar amyloid assembly properties that are not common with other fibril forming proteins. It is one of the first shown to form ring shaped amyloids and other complexes in vitro. Lastly equine lysozyme forms complex with oleic acid, a unique form ELOA, which contributes to the family of the human and bovine lactalbumin analogs HAMLET and BAMLET.
|
|
| 5844. |
- Morsi, Dalia S., et al.
(författare)
-
Anti-proliferative and immunomodulatory potencies of cinnamon oil on Ehrlich ascites carcinoma bearing mice
- 2022
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 12:1
-
Tidskriftsartikel (refereegranskat)abstract
- Cinnamon is a well-known natural spice and flavoring substance used worldwide. The objective of the present work is to explore the possible antitumor and immunomodulatory potencies of cinnamon essential oil (Cinn) on Ehrlich ascites carcinoma (EAC). A total of fifty female Swiss albino mice were sub-grouped into five groups (n = 10), namely, normal (a non-tumorized and non-treated) group; EAC-tumorized and non-treated group; Cinn (non-tumorized mice received Cinn, 50 mg/kg per body weight daily) group; a group of EAC-tumorized mice treated with Cinn and the final positive control group of EAC-tumorized mice received cisplatin. Eight compounds were identified from Cinn using UPLC-MS-Qtof and NMR analysis. Compared to EAC untreated group, Cinn successfully (P < 0.05) inhibited tumor growth by reducing tumor cell count (45%), viability (53%) and, proliferation accompanied by the inhibition of tumor growth rate. Moreover, a significant (P < 0.05) arrest in the cell cycle at G0/G1 phase was noticed following Cinn treatments (~ 24.5%) compared to EAC group. Moreover, Cinn markedly evoked an antitumor immune response by elevating the percentage of splenic T helper (CD3+CD4+) and T cytotoxic (CD3+CD8+) cells. It is noteworthy that Cinn treatments significantly restored different hematological alterations as well as liver and kidney functions in EAC-tumorized mice. In conclusion, results suggest that Cinn has a good antitumor and immunostimulatory potencies against Ehrlich ascites carcinoma in vivo. The mechanism underlying its antitumor activity may be attributed to its immunostimulatory effects which increase its potential as a promising anticancer candidate.
|
|
| 5845. |
- Morud, Julia, 1984, et al.
(författare)
-
Nicotine produces chronic behavioral sensitization with changes in accumbal neurotransmission and increased sensitivity to re-exposure
- 2016
-
Ingår i: Addiction Biology. - : Wiley. - 1355-6215. ; 21:2, s. 397-406
-
Tidskriftsartikel (refereegranskat)abstract
- Tobacco use is often associated with long-term addiction as well as high risk of relapse following cessation. This is suggestive of persistent neural adaptations, but little is known about the long-lasting effects of nicotine on neural circuits. In order to investigate the long-term effects of nicotine exposure, Wistar rats were treated for 3 weeks with nicotine (0.36mg/kg), and the duration of behavioral and neurophysiological adaptations was evaluated 7 months later. We found that increased drug-induced locomotion persisted 7 months after the initial behavioral sensitization. In vitro analysis of synaptic activity in the core and shell of the nucleus accumbens (nAc) revealed a decrease in input/output function in both regions of nicotine-treated rats as compared to vehicle-treated control rats. In addition, administration of the dopamine D2 receptor agonist quinpirole (5M) significantly increased evoked population spike amplitude in the nAc shell of nicotine-treated rats as compared to vehicle-treated control rats. To test whether nicotine exposure creates long-lasting malleable circuits, animals were re-exposed to nicotine 7 months after the initial exposure. This treatment revealed an increased sensitivity to nicotine among animals previously exposed to nicotine, with higher nicotine-induced locomotion responses than observed initially. In vitro electrophysiological recordings in re-exposed rats detected an increased sensitivity to dopamine D2 receptor activation. These results suggest that nicotine produces persistent neural adaptations that make the system sensitive and receptive to future nicotine re-exposure.
|
|
| 5846. |
- Moscatelli, Ilana, et al.
(författare)
-
Targeting NSG Mice Engrafting Cells with a Clinically Applicable Lentiviral Vector Corrects Osteoclasts in Infantile Malignant Osteopetrosis
- 2018
-
Ingår i: Human Gene Therapy. - : Mary Ann Liebert Inc. - 1043-0342 .- 1557-7422. ; 29:8, s. 938-949
-
Tidskriftsartikel (refereegranskat)abstract
- Infantile malignant osteopetrosis (IMO) is a rare, lethal, autosomal recessive disorder characterized by nonfunctional osteoclasts. More than 50% of the patients have mutations in the TCIRG1 gene, encoding for a subunit of the osteoclast proton pump. The aim of this study was to develop a clinically applicable lentiviral vector expressing TCIRG1 to correct osteoclast function in IMO. Two mammalian promoters were compared: elongation factor 1α short (EFS) promoter and chimeric myeloid promoter (ChimP). EFS promoter was chosen for continued experiments, as it performed better. IMO osteoclasts corrected in vitro by a TCIRG1-expressing lentiviral vector driven by EFS (EFS-T) restored Ca2+ release to 92% and the levels of the bone degradation product CTX-I to 95% in the media compared to control osteoclasts. IMO CD34+ cells from five patients transduced with EFS-T were transplanted into NSG mice. Bone marrow was harvested 9–19 weeks after transplantation, and human CD34+ cells were selected, expanded, and seeded on bone slices. Vector-corrected IMO osteoclasts had completely restored Ca2+ release. CTX-I levels in the media were 33% compared to normal osteoclasts. Thus, in summary, evidence is provided that transduction of IMO CD34+ cells with the clinically applicable EFS-T vector leads to full rescue of osteoclasts in vitro and partial rescue of osteoclasts generated from NSG mice engrafting hematopoietic cells. This supports the continued clinical development of gene therapy for IMO.
|
|
| 5847. |
- Mosén, Henrik, et al.
(författare)
-
Impaired glucose-stimulated insulin secretion in the GK rat is associated with abnormalities in islet nitric oxide production.
- 2008
-
Ingår i: Regulatory Peptides. - : Elsevier BV. - 1873-1686 .- 0167-0115. ; 151, s. 139-146
-
Tidskriftsartikel (refereegranskat)abstract
- We investigated implications of nitric oxide (NO) derived from islet neuronal constitutive NO synthase (ncNOS) and inducible NOS (iNOS) on insulin secretory mechanisms in the mildly diabetic GK rat. Islets from GK rats and Wistar controls were analysed for ncNOS and iNOS by HPLC, immunoblotting and immunocytochemistry in relation to insulin secretion stimulated by glucose or l-arginine in vitro and in vivo. No obvious difference in ncNOS fluorescence in GK vs control islets was seen but freshly isolated GK islets displayed a marked iNOS expression and activity. After incubation at low glucose GK islets showed an abnormal increase in both iNOS and ncNOS activities. At high glucose the impaired glucose-stimulated insulin release was associated with an increased iNOS expression and activity and NOS inhibition dose-dependently amplified insulin secretion in both GK and control islets. This effect by NOS inhibition was also evident in depolarized islets at low glucose, where forskolin had a further amplifying effect in GK but not in control islets. NOS inhibition increased basal insulin release in perfused GK pancreata and amplified insulin release after glucose stimulation in both GK and control pancreata, almost abrogating the nadir separating first and second phase in controls. A defective insulin response to l-arginine was seen in GK rats in vitro and in vivo, being partially restored by NOS inhibition. The results suggest that increased islet NOS activities might contribute to the defective insulin response to glucose and l-arginine in the GK rat. Excessive iNOS expression and activity might be deleterious for the beta-cells over time.
|
|
| 5848. |
- Moses, J, et al.
(författare)
-
Biosynthesis of the proteoglycan decorin -- identification of intermediates in galactosaminoglycan assembly
- 1997
-
Ingår i: European Journal of Biochemistry. - : Wiley. - 0014-2956 .- 1432-1033. ; 248:3, s. 767-774
-
Tidskriftsartikel (refereegranskat)abstract
- Biosynthesis of decorin was investigated by incubating a rat fibroblast cell line with various radiolabelled protein and galactosaminoglycan precursors. The following cell-associated and distinct intermediates were isolated and identified: a pool of non-glycosylated core protein, two pools of decorin with incomplete chains, one with three sulphated disaccharide repeats and another with five or more sulphated disaccharide repeats, as well as decorin with mature chains. Results of pulse/chase experiments indicated that these pools represented discrete stages in chain growth. Treatment with brefeldin A, which blocks transport from the endoplasmic reticulum to the Golgi, resulted in accumulation of decorin with an incomplete chain containing six or seven largely unsulphated disaccharide repeats. During recovery from drug treatment, 4-sulfation reappeared earlier than 6-sulfation. The results suggest that the galactosaminoglycan assembly-line consists of separate multienzyme complexes that build only a limited section of the chain. Furthermore, brefeldin A causes segregation of compartments involved in separate stages of the assembly line. In an earlier report [Moses, J., Oldberg. A., Cheng, F. & Fransson, L.-A. (1997) Eur. J. Biochem. 248, 521-526] we took advantage of such segregation to identify and characterize a transient 2-phosphorylation of xylose in the linkage region.
|
|
| 5849. |
- Moses, Sara, et al.
(författare)
-
Smooth muscle cell response to mechanical injury involves intracellular calcium release and ERK1/ERK2 phosphorylation
- 2001
-
Ingår i: Experimental Cell Research. - : Elsevier BV. - 1090-2422 .- 0014-4827. ; 269:1, s. 88-96
-
Tidskriftsartikel (refereegranskat)abstract
- We have investigated possible signaling pathways coupled to injury-induced ERK1/2 activation and the subsequent initiation of vascular rat smooth muscle cell migration and proliferation. Aortic smooth muscle cells were cultured to confluency and subjected to in vitro injury under serum-free conditions. In fluo-4-loaded cells, injury induced a rapid wave of intracellular Ca(2+) release that propagated about 200 microm in radius from the injured zone, reached a peak in about 20 s, and subsided to the baseline within 2 min. The wave was abolished by prior treatment with the sarcoplasmic reticulum ATPase inhibitor thapsigargin, but not by omission of extracellular Ca(2+). ERK1/2 activation reached a peak at 10 min after injury and was inhibited by the MEK1 inhibitor PD98059, as well as by thapsigargin, fluphenazine, genistein, and the Src inhibitor PP2. These inhibitors also reduced [(3)H]thymidine incorporation and migration of cells into the injured area determined at 48 h after injury. These results show that mechanical injury to vascular smooth muscle cells induces a Ca(2+) wave which is dependent on intracellular Ca(2+) release. Furthermore, the injury activates ERK1/2 phosphorylation as well as cell migration and replication.
|
|
| 5850. |
- Moskalenko, R. A., et al.
(författare)
-
Involvement of proinflammatory S100A9/A8 in the atherocalcinosis of aortic valves
- 2017
-
Ingår i: Pathologia. - : Zaporizʹkyĭ derz͡havnyĭ medychnyĭ universytet. - 2306-8027. ; :1, s. 49-56
-
Tidskriftsartikel (refereegranskat)abstract
- According to the results of the Euro-Heart Survey on Vascular Heart Disease the most common pathology is nonrheumatic aortic stenosis, it is also called as calcific aortic valve stenosis (CAVS), as in its pathogenesis the process of biomineralization of valve cusps and ring plays the main role. The aim of the work is the immunohistochemical study of mineralized tissue of aortic heart valves, which are affected by atherocalcinosis. Materials and methods. 30 samples of mineralized aortic valves (I group) and 10 samples of aortic valve without evidence of biomineralization (II group - control) were studied. Immunohistochemical study of expression of collagen (Collagen I), CD68, myeloperoxidase (MPO), calgranulin A (S100A8), calgranulin B (8100A9), caspase 3 (Casp 3) and osteopontin (OPN) was conducted in AV tissue of both groups. Results. In CAV tissues the fibrillar component (collagen I) growths was found, but the quantitative and qualitative compositions of CD68+ circulating inflammatory cells are not significantly different from the control group. CAVs contain much more MPO+-cells (p <0.001) in comparison to the group of AVs without biomineralization. Our data show a significant increase of the S100A9 and OPN expression in the mineralized tissue of AVs (p <0.01). Also, a higher expression level of Casp3 and MPO was found in CAVs (p <0.05). Comparing the first and the second groups of AVs connection between the expression of S100A8 was not determined. Conclusion. High Casp 3 expression confirms the increased level of cell elimination in the CAVs tissue, which is obviously connected with the impact of high local concentrations of S100A9. These facts can contribute to the development of pathological biomineralization of AV. Since osteopontin inhibits the hydroxyapatite formation by binding to the surface of the crystals, its hyperproduction is a counteracting factor against biomineralization in AV tissue.
|
|
