scholarly journals Method: Isolation of Epithelial Cell RNA from Frozen Jejunum Segments While Minimizing Smooth Muscle Cell RNA Contamination

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1182-1182
Author(s):  
Shumao Ye ◽  
Nirupa Matthan ◽  
Stefania Lamon-Fava ◽  
Gloria Solano-Aguilar ◽  
Jerrold Turner ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Epithelial Cell ◽  
Smooth Muscle Cells ◽  
Traditional Method ◽  
Rna Isolation ◽  
Current Method ◽  
Muscle Cells ◽  
Cell Types ◽  
Enrichment Score ◽  
Rna Quality

Abstract Objectives High RNA quality is a prerequisite for accurate PCR and sequencing results. Dissecting a specific tissue fraction from frozen samples while maintaining RNA quality is challenging. Starting with frozen pig jejunum segments, we describe a novel method to isolate epithelial cell RNA while minimizing contamination with smooth muscle cell RNA. Methods Jejunum tissue segments from Ossabaw pigs (N = 30) were snap-frozen in liquid nitrogen upon harvest from a diet-statin study and stored at −80°C. At the time of RNA isolation samples were incubated in prechilled RNAlater-ICE at −20°C for 24 hours, opened longitudinally, and epithelium cleanly separated from the muscle layer using a scalpel and tweezers. Total RNA was extracted from the epithelium using TRI-reagent. RNA Quality Indicator (RQI) of total RNA was measured using Experion RNA StdSens Analysis kit. RNA-sequencing was performed on Illumina NextSeq 500 platform. Raw sequencing data were aligned to the domestic pig (sus scrofa 11.1) reference genome and applied to subsequent analyses. xCell, a gene signature-based tool trained by thousands of single cell types from various sources, was used to estimate enrichment of epithelial cells (target) and smooth muscle cells (contamination) across samples. A Student t-test was used to compare the enrichment scores of these two cell types between the current method and a traditional method (small jejunal pieces collected at necropsy and stored frozen until RNA isolation). Results RQI ranged from 8.6 to 9.7, above the standard for RNA sequencing (RQI > 8). The enrichment score of epithelial cells was significantly higher in the current method (mean = 0.030, SD = 0.006) compared to the traditional method (mean = 0.016, SD = 0.013) (P < 0.0001). The enrichment score of smooth muscle cells was significantly lower in the current method (mean = 0.043, SD = 0.035) compared to the traditional method (mean = 0.13, SD = 0.093) (P < 0.0001). Conclusions The current method effectively maintained RNA quality and minimized contamination of epithelial with smooth muscle cells. This method may be applicable to other frozen archived tissues that require a single tissue source of RNA. Funding Sources USDA-ARS-NEA, JM-USDA-HNRCA, and Tufts University.

Metabolic modulation of hexokinase association with mitochondria in living smooth muscle cells

1996 ◽  
Vol 270 (2) ◽  
pp. C488-C499 ◽  
Author(s):  
R. M. Lynch ◽  
W. Carrington ◽  
K. E. Fogarty ◽  
F. S. Fay
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Energy State ◽  
Single Cells ◽  
Inverse Correlation ◽  
Muscle Cells ◽  
Cell Types ◽  
Differential Sensitivity ◽  
Similar Distribution ◽  
Apparent Difference

Hexokinase isoform I binds to mitochondria of many cell types. It has been hypothesized that this association is regulated by changes in the concentrations of specific cellular metabolites. To study the distribution of hexokinase in living cells, fluorophore-labeled functional hexokinase I was prepared. After microinjection into A7r5 smooth muscle cells, hexokinase localized to distinct structures identified as mitochondria. The endogenous hexokinase demonstrated a similar distribution with the use of immunocytochemistry. 2-Deoxyglucose elicited an increase in glucose 6-phosphate (G-6-P) and a decrease in ATP levels and diminished hexokinase binding to mitochondria in single cells. 3-O-methylglucose elicited slowly developing decreases in all three parameters. In contrast, cyanide elicited a rapid decrease in both ATP and hexokinase binding. Analyses of changes in metabolite levels and hexokinase binding indicate a positive correlation between binding and cell energy state as monitored by ATP. On the other hand, only in the presence of 2-deoxyglucose was the predicted inverse correlation between binding and G-6-P observed. Unlike the relatively large changes in distribution observed with the fluorescent-injected hexokinase, cyanide caused only a small decrease in the localization of endogenous hexokinase with mitochondria. These findings suggest that changes in the concentrations of specific metabolites can alter the binding of hexokinase I to specific sites on mitochondria. Moreover, the apparent difference in sensitivity of injected and endogenous hexokinase to changes in metabolites may reflect the presence of at least two classes of binding mechanisms for hexokinase, with differential sensitivity to metabolites.

Abstract 238: ABCA1 and HDL3 are Required to Modulate Smooth Muscle Cells Trandifferentiation in a Myocardin-miR143/145-dependent Process

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Silvia Castiglioni ◽  
Alessio Vettore ◽  
Lorenzo Arnaboldi ◽  
Laura Calabresi ◽  
Alberto Corsini ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Muscle Cells ◽  
Cell Types ◽  
Foam Cells ◽  
Knock Out ◽  
Phenotypic Changes ◽  
Basal Expression ◽  
Basal Expression Level

Cells of the artery wall may accumulate free cholesterol and cholesteryl esters becoming foam cells. Up to 50% of foam cells in human lesions originates from smooth muscle cells (SMCs). Arterial SMCs express the ATP binding cassette (ABC) transporter ABCA1 and, upon cholesterol loading, express macrophage markers and a phagocytic activity. To characterize the role of ABCA1 and HDL3 in this transdifferentiation process, we evaluated the phenotypic changes in SMCs isolated from wild type (WT) and ABCA1 knock out (KO) mice and how HDL3 affects these changes. Cholesterol loading causes the downregulation of the expression of SMC markers including ACTA2, alpha-tropomyosin and myosin heavy chain and increases the expression of macrophage-related genes such as CD68, Mac-2, SRB1, MMPs, ABCG1 and ABCA1. HDL3 treatment in WT cells is able to normalize the expression of ACTA2, while the expression of macrophage-related genes is reduced. On the contrary, the preventive effect of HDL3 is completely lost in ABCA1 KO cells. Interestingly, the presence of HDL3 does not differently affect neutral lipid accumulation in WT or ABCA1 KO cells but stimulates phospholipids removal only in WT cells. ApoAI addition does not reverse the phenotypic changes induced by cholesterol not only in KO but also in WT cells. Moreover, cholesterol loading reduces the expression of myocardin, the master SMC specific-transcriptional coactivator involved in SMC differentiation, by up to 55% (p<0.01 vs respective control) in both cell types. HDL3 normalizes myocardin levels in WT cells while it does not have any effect in ABCA1 KO cells. Similar results are obtained evaluating the levels of miR-143/145, which positively regulate myocardin. The basal expression level of KLF4, a myocardin repressor, is almost double in ABCA1 KO cells compared to WT. After cholesterol loading, KLF4 is slightly reduced in WT cells, while its expression is halved in ABCA1 KO cells. HDL3 restores KLF4 to basal levels in KO cells, but it further reduces them in WT cells. These results indicate that HDL3, modulating the miR143/145-myocardin axis in SMC, prevents the cholesterol-induced gene expression modification regardless of its cholesterol unloading capacity and the presence of ABCA1 is required.

The role of globins in cardiovascular physiology

2021 ◽  
Author(s):  
T.C. Steven Keller ◽  
Christophe Lechauve ◽  
Alexander S Keller ◽  
Steven Brooks ◽  
Mitchell J Weiss ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Central Nervous System ◽  
Nervous System ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Muscle Cells ◽  
Cell Types ◽  
Specific Cell ◽  
In Cells

Globin proteins exist in every cell type of the vasculature, from erythrocytes to endothelial cells, vascular smooth muscle cells, and peripheral nerve cells. Many globin subtypes are also expressed in muscle tissues (including cardiac and skeletal muscle), in other organ-specific cell types, and in cells of the central nervous system. The ability of each of these globins to interact with molecular oxygen (O2) and nitric oxide (NO) is preserved across these contexts. Endothelial α-globin is an example of extra-erythrocytic globin expression. Other globins, including myoglobin, cytoglobin, and neuroglobin are observed in other vascular tissues. Myoglobin is observed primarily in skeletal muscle and smooth muscle cells surrounding the aorta or other large arteries. Cytoglobin is found in vascular smooth muscle but can also be expressed in non-vascular cell types, especially in oxidative stress conditions after ischemic insult. Neuroglobin was first observed in neuronal cells, and its expression appears to be restricted mainly to the central and peripheral nervous systems. Brain and central nervous system neurons expressing neuroglobin are positioned close to many arteries within the brain parenchyma and can control smooth muscle contraction and, thus, tissue perfusion and vascular reactivity. Overall, reactions between NO and globin heme-iron contribute to vascular homeostasis by regulating vasodilatory NO signals and scaveging reactive species in cells of the mammalian vascular system. Here, we discuss how globin proteins affect vascular physiology with a focus on NO biology, and offer perspectives for future study of these functions.

Laser-assisted microdissection and real-time PCR detect anti-inflammatory effect of perfluorocarbon

2003 ◽  
Vol 285 (1) ◽  
pp. L55-L62 ◽  
Author(s):  
Katharina von der Hardt ◽  
Michael Andreas Kandler ◽  
Ludger Fink ◽  
Ellen Schoof ◽  
Jörg Dötsch ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Mrna Expression ◽  
Vascular Smooth Muscle Cells ◽  
Alveolar Macrophages ◽  
Real Time Pcr ◽  
Muscle Cells ◽  
Cell Types ◽  
Anti Inflammatory ◽  
Inflammatory Effect

The aim of this study was to identify cell types involved in the anti-inflammatory effect of ventilation with perfluorocarbon in vivo. Fifteen anesthetized, surfactant-depleted piglets received either aerosolized perfluorocarbon (Aerosol-PFC), partial liquid ventilation (rLV) at functional residual capacity (FRC) volume (FRC-PLV), or intermittent mandatory ventilation (control). After laser-assisted microdissection of different lung cell types, mRNA expression of IL-8 and ICAM-1 was determined using TaqMan real-time PCR normalized to hypoxanthine phosphoribosyltransferase (HPRT). IL-8 mRNA expression (means ± SE; control vs. Aerosol-PFC) was 356 ± 142 copies IL-8 mRNA/copy HPRT mRNA vs. 3.5 ± 1.8 in alveolar macrophages ( P <0.01); 208 ± 108 vs. 2.7 ± 0.8 in bronchiolar epithelial cells ( P <0.05); 26 ± 11 vs. 0.7 ± 0.2 in alveolar septum cells ( P <0.01); 2.8 ± 1.0 vs. 0.8 ± 0.4 in bronchiolar smooth muscle cells ( P <0.05); and 1.1 ± 0.4 vs. 0.2 ± 0.05 in vascular smooth muscle cells ( P <0.05). With FRC-PLV, IL-8/HPRT mRNA expression was significantly lower in macrophages, bronchiolar epithelial, and vascular smooth muscle cells. ICAM-1 mRNA expression in vascular endothelial cells remained unchanged. Predominantly, alveolar macrophages and bronchiolar epithelial cells were involved in the inflammatory pulmonary process. The anti-inflammatory effect of Aerosol-PFC was most pronounced.

scholarly journals Spatially selective myosin regulatory light chain regulation is absent in dedifferentiated vascular smooth muscle cells but is partially induced by fibronectin and Klf4

2019 ◽  
Vol 316 (4) ◽  
pp. C509-C521 ◽  
Author(s):  
Tsubasa S. Matsui ◽  
Shinji Deguchi
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Smooth Muscle Cells ◽  
Light Chain ◽  
Muscle Cells ◽  
Cell Types ◽  
Myosin Regulatory Light Chain ◽  
Phosphorylation State ◽  
Spatial Regulation

The phosphorylation state of myosin regulatory light chain (MRLC) is central to the regulation of contractility that impacts cellular homeostasis and fate decisions. Rho-kinase (ROCK) and myosin light chain kinase (MLCK) are major kinases for MRLC documented to selectively regulate MRLC in a subcellular position-specific manner; specifically, MLCK in some nonmuscle cell types works in the cell periphery to promote migration, while ROCK does so at the central region to sustain contractility. However, it remains unclear whether or not the spatially selective regulation of the MRLC kinases is universally present in other cell types, including dedifferentiated vascular smooth muscle cells (SMCs). Here, we demonstrate the absence of the spatial regulation in dedifferentiated SMCs using both cell lines and primary cells. Thus, our work is distinct from previous reports on cells with migratory potential. We also observed that the spatial regulation is partly induced upon fibronectin stimulation and Krüppel-like factor 4 overexpression. To find clues to the mechanism, we reveal how the phosphorylation state of MRLC is determined within dedifferentiated A7r5 SMCs under the enzymatic competition among three major regulators ROCK, MLCK, and MRLC phosphatase (MLCP). We show that ROCK, but not MLCK, predominantly regulates the MRLC phosphorylation in a manner distinct from previous in vitro-based and in silico-based reports. In this ROCK-dominating cellular system, the contractility at physiological conditions was regulated at the level of MRLC diphosphorylation, because its monophosphorylation is already saturated. Thus, the present study provides insights into the molecular basis underlying the absence of spatial MRLC regulation in dedifferentiated SMCs.

scholarly journals Expression of a naturally occurring angiotensin AT1 receptor cleavage fragment elicits caspase-activation and apoptosis

2011 ◽  
Vol 301 (5) ◽  
pp. C1175-C1185 ◽  
Author(s):  
Julia L. Cook ◽  
Akannsha Singh ◽  
Dawn deHaro ◽  
Jawed Alam ◽  
Richard N. Re
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Fold Increase ◽  
Muscle Cells ◽  
Cell Types ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Breast Adenocarcinoma ◽  
Protein Fusion ◽  
Cleavage Fragment ◽  
Carboxy Terminal

Several transmembrane receptors are documented to accumulate in nuclei, some as holoreceptors and others as cleaved receptor products. Our prior studies indicate that a population of the 7-transmembrane angiotensin type-1 receptor (AT1R) is cleaved in a ligand-augmented manner after which the cytoplasmic, carboxy-terminal cleavage fragment (CF) traffics to the nucleus. In the present report, we determine the precise cleavage site within the AT1R by mass spectrometry and Edman sequencing. Cleavage occurs between Leu(305) and Gly(306) at the junction of the seventh transmembrane domain and the intracellular cytoplasmic carboxy-terminal domain. To evaluate the function of the CF distinct from the holoreceptor, we generated a construct encoding the CF as an in-frame yellow fluorescent protein fusion. The CF accumulates in nuclei and induces apoptosis in CHO-K1 cells, rat aortic smooth muscle cells (RASMCs), MCF-7 human breast adenocarcinoma cells, and H9c2 rat cardiomyoblasts. All cell types show nuclear fragmentation and disintegration, as well as evidence for phosphotidylserine displacement in the plasma membrane and activated caspases. RASMCs specifically showed a 5.2-fold increase ( P < 0.001) in CF-induced active caspases compared with control and a 7.2-fold increase ( P < 0.001) in cleaved caspase-3 (Asp174). Poly(ADP-ribose)polymerase was upregulated 4.8-fold ( P < 0.001) in CF expressing cardiomyoblasts and colocalized with terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). CF expression also induces DNA laddering, the gold-standard for apoptosis in all cell types studied. CF-induced apoptosis, therefore, appears to be a general phenomenon as it is observed in multiple cell types including smooth muscle cells and cardiomyoblasts.

scholarly journals An integrin receptor on normal and thrombasthenic platelets that binds thrombospondin [see comments]

Blood ◽  
1989 ◽  
Vol 74 (6) ◽  
pp. 2022-2027 ◽  
Author(s):  
J Lawler ◽  
RO Hynes
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Muscle Cells ◽  
Cell Types ◽  
Melanoma Cells ◽  
Human Platelets ◽  
Alpha Subunit ◽  
Adhesive Proteins ◽  
Alpha V Beta 3

Abstract The members of the integrin family of membrane glycoprotein heterodimer complexes function as cell surface receptors for adhesive proteins. We report here on the identification of two integrins on the surface of human platelets that bind to thrombospondin. When platelet membrane proteins are radiolabeled with 125I-lactoperoxidase, solubilized in n- octylglucoside, (Boehringer Mannheim Biochemicals, Indianapolis, IN), and applied to a column of thrombospondin-Sepharose, both complexes are bound to the column and specifically eluted with the peptide GRGDSP. One of these integrins, glycoprotein (GP) IIb-IIIa, appears to bind relatively weakly. The second integrin shares the same beta subunit (beta 3 or GPIIIa), but has a distinct alpha subunit that comigrates with the alpha subunit (alpha v) of the vitronectin receptor (VnR) on endothelial cells and reacts with a monoclonal antibody, LM142, which was raised against an integrin from M21 melanoma cells. The alpha v beta 3 integrin is present on a variety of cell types and appears to act as a receptor for thrombospondin on endothelial and smooth muscle cells. On endothelial and M21 melanoma cells this receptor is also involved in adhesion to fibrinogen, vitronectin, and von Willebrand factor (vWF). The alpha v beta 3 integrin is present at approximately equal levels on normal and thrombasthenic platelets, whereas levels of GPIIb-IIIa are greatly reduced on thrombasthenic platelets. The alpha v beta 3 integrin on thrombasthenic platelets also binds to thrombospondin-Sepharose and can be eluted with the peptide GRGDSP. These data indicate that the alpha v beta 3 integrin on platelets, endothelial cells, and smooth muscle cells functions as an Arg-Gly-Asp (RGD)-dependent receptor for thrombospondin.

KVα1 channels in murine arterioles: differential cellular expression and regulation of diameter

2001 ◽  
Vol 281 (3) ◽  
pp. H1057-H1065 ◽  
Author(s):  
A. Cheong ◽  
A. M. Dedman ◽  
S. Z. Xu ◽  
D. J. Beech
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Expression Profiles ◽  
Second Messengers ◽  
Expression Patterns ◽  
Muscle Cells ◽  
Cell Types ◽  
Specific Expression ◽  
Major Function ◽  
Cellular Expression

The primary objectives of this study were to reveal cell-specific expression patterns and functions of voltage-gated K+ channel (KVα1) subunits in precapillary arterioles of the murine cerebral circulation. KVα1 were detected using peptide-specific antibodies in immunofluorescence and Western blotting assays. KV1.2 was localized almost exclusively to endothelial cells, whereas KV1.5 was discretely localized to the nerves and nerve terminals that innervate the arterioles. KV1.5 also localized specifically to arteriolar nerves in human pial membrane. KV1.5 was notable for its absence from smooth muscle cells. KV1.3, KV1.4, and KV1.6 were localized to endothelial and smooth muscle cells, although KV1.4 had a low expression level. KV1.1 was not expressed. Therefore, we show that different cell types of pial arterioles have distinct physiological expression profiles of KVα1, conferring the possibility of differential modulation by extracellular and second messengers. Furthermore, we show recombinant agitoxin-2 and margatoxin are potent vasoconstrictors, suggesting that KVα1 subunits have a major function in determining arteriolar resistance to blood flow.

The Proadhesive Properties of Multimerin in Supporting Cellular Adhesion: Evidence for RGD and Non-RGD Dependent Adhesive Mechanisms.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3917-3917
Author(s):  
Frederic Adam ◽  
Shilun Zheng ◽  
Nilesh Joshi ◽  
Youko Suehiro ◽  
David S. Kelton ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Muscle Cells ◽  
Cell Types ◽  
Structural Features ◽  
Cellular Adhesion ◽  
Cellular Activation ◽  
Rgd Sequence ◽  
Rgd Site

Abstract Multimerin is a large soluble protein, with an uncertain function, found in platelets, megakaryocytes, endothelium and extracellular matrix fibers but not in plasma. The observation that multimerin contains structural features of an adhesive protein, including an Arg-Gly-Asp (RGD) sequence, led us to investigate its ability to support adhesion of platelets, megakaryocytes, endothelial cells and other cell types. Multimerin had the ability to support the adhesion of both platelets and megakaryocytes and this required cellular activation and the multimerin RGD site. Studies of normal and Glanzmann platelets indicated that multimerin interacted with the major platelet integrin receptor, αIIbβ3 and radioimmunoprecipitation analyses confirmed that multimerin bound to αIIbβ3. Multimerin also supported adhesion of endothelial cells, neutrophils and other cells including smooth muscle cells, fibroblast cells, human embryonic kidney (HEK293) and epithelial cells. Unlike platelets, these cells do not express αIIbβ3; this indicated that other integrin or non-integrin receptors could be involved in cellular adhesion to multimerin. Comparisons of cell adhesion to wild-type and RGE-multimerin indicated that unlike platelets and megakaryocytes, some other cell types (e.g. endothelial cells, smooth muscle cells and neutrophils) were capable of adhering to RGE-multimerin. This suggested that cellular adhesion to multimerin occurs by both RGD and non-RGD dependent mechanisms. Finally, unlike platelets, megakaryocytes and neutrophils, adhesion of other cell types to multimerin did not require cellular activation. In conclusion, our data indicate multimerin has fairly broad proadhesive properties, involving RGD and non-RGD dependent mechanisms, and that cellular receptors including αIIbβ3 interact with multimerin to mediate its binding to activated platelets, endothelial cells and potentially other cell types.

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