scholarly journals Dietary Lipid Modulation of Intestinal Serotonin in Ballan Wrasse (Labrus bergylta)—In Vitro Analyses

2021 ◽  
Vol 12 ◽  
Author(s):  
Angela Etayo ◽  
Hoang T. M. D. Le ◽  
Pedro Araujo ◽  
Kai K. Lie ◽  
Øystein Sæle
Keyword(s):  
Mrna Expression ◽  
Tryptophan Hydroxylase ◽  
Ex Vivo ◽  
Dietary Lipid ◽  
Serotonergic System ◽  
Organ Bath ◽  
Serotonergic Neurons ◽  
Gut Epithelium ◽  
Ec Cells ◽  
Labrus Bergylta

Serotonin (5-HT) is pivotal in the complex regulation of gut motility and consequent digestion of nutrients via multiple receptors. We investigated the serotonergic system in an agastric fish species, the ballan wrasse (Labrus bergylta) as it represents a unique model for intestinal function. Here we present evidence of the presence of enterochromaffin cells (EC cells) in the gut of ballan wrasse comprising transcriptomic data on EC markers like adra2a, trpa1, adgrg4, lmxa1, spack1, serpina10, as well as the localization of 5-HT and mRNA of the rate limiting enzyme; tryptophan hydroxylase (tph1) in the gut epithelium. Second, we examined the effects of dietary marine lipids on the enteric serotonergic system in this stomach-less teleost by administrating a hydrolyzed lipid bolus in ex vivo guts in an organ bath system. Modulation of the mRNA expression from the tryptophan hydroxylase tph1 (EC cells isoform), tph2 (neural isoform), and other genes involved in the serotonergic machinery were tracked. Our results showed no evidence to confirm that the dietary lipid meal did boost the production of 5-HT within the EC cells as mRNA tph1 was weakly regulated postprandially. However, dietary lipid seemed to upregulate the post-prandial expression of tph2 found in the serotonergic neurons. 5-HT in the intestinal tissue increased 3 hours after “exposure” of lipids, as was observed in the mRNA expression of tph2. This suggest that serotonergic neurons and not EC cells are responsible for the substantial increment of 5-HT after a lipid-reach “meal” in ballan wrasse. Cells expressing tph1 were identified in the gut epithelium, characteristic for EC cells. However, Tph1 positive cells were also present in the lamina propria. Characterization of these cells together with their implications in the serotonergic system will contribute to broad the scarce knowledge of the serotonergic system across teleosts.

scholarly journals A119 AN EX VIVO MODEL TO STUDY THE GUT SEROTONERGIC SYSTEM RESPONSE TO LIVE AND HEAT-KILLED LACTOBACILLUS RHAMNOSUS STRAIN JB-1

2020 ◽  
Vol 3 (Supplement_1) ◽  
pp. 138-140
Author(s):  
T Javkar ◽  
M Paul ◽  
A Stanisz ◽  
P Forsythe
Keyword(s):  
Gene Expression ◽  
Tryptophan Hydroxylase ◽  
Ex Vivo ◽  
Lactobacillus Rhamnosus ◽  
Monoamine Oxidase A ◽  
Serotonergic System ◽  
In Vivo Experiments ◽  
Mao A ◽  
Ec Cells

Abstract Background Enterochromaffin (EC) cells are one of the most abundant enteroendocrine cells in the intestinal epithelium, responsible for producing and storing the largest pool of serotonin or 5-hydroxytryptamine (5-HT) in the body. 5-HT has been shown to be important for modulating a large number of gastrointestinal reflexes in health and disease. 5-HT can stimulate extrinsic (vagal and spinal afferents) or intrinsic primary afferent neurons (IPANs) which are involved in motility, secretion and vasodilation within the intestines. Where EC cell localized enzyme tryptophan hydroxylase (TpH) isoform 1 is responsible for 5-HT synthesis, serotonin reuptake transporter (Sert) and monoamine oxidase A (Mao A) are responsible for termination by uptake and metabolism of 5-HT respectively. Our previous research has demonstrated the effects Lactobacillus rhamnosus (JB-1) on the firing frequency of spinal nerve fibres and motility. Increasing interest is being focused on potential health benefits of heat-inactivated microbes and purified bacterial components. However, the effect of these heat-killed bacteria on the intestinal epithelium cells, particularly on EC cells, is unknown. Aims Small intestinal organoids are shown to recapitulate in vivo characteristics of the small intestine epithelium. The present study aims to assess the suitability of intestinal organoids to study bacterial effects on the serotonergic system in the gut. Here we determined changes in the gene expression of key mediators in the serotonergic system [serotonin reuptake transporter (Sert), tryptophan hydroxylase-1 (Tph-1) and monoamine oxidase A (Mao A)] in response to live and heat-killed JB-1. Methods Male C57bl/6 mice aged 6–8 weeks were used for both ex vivo and in vivo experiments. Jejunal organoids were grown from whole crypts isolated using DTT-EDTA solution. Live and heat-killed JB-1 bacteria were used as treatments. Gene expression analysis was performed on jejunal organoids and jejunum tissue using qRT-PCR. Results JB-1 induced a significant increase in gene expression of Sert, Mao A and Tph-1. No significant difference was observed between the effects of live and heat-killed bacteria. In contrast the JB-1 increased expression of the peptide hormone CCK. Effects of JB-1 on gene expression in organoid culture were reflective of changes observed in in vivo experiments involving feeding of the bacteria. Conclusions Ex vivo organoid culture could be a useful tool in studying mechanisms underlying bacterial effects on serotonergic signalling. The observation that heat-killed bacteria produced comparable effects to the live organism suggests the possibility of isolating active 5-HT modulating components from these strains. Future research will focus on identifying such bacterial components and how their effects on gene expression influence serotonin availability Funding Agencies None

Myometrial Responses to Beta-Adrenoceptor Antagonists in Gynecological Malignancies

2021 ◽  
pp. 1-8
Author(s):  
Beata Modzelewska ◽  
Marcin Jóźwik ◽  
Tomasz Kleszczewski ◽  
Stanisław Sulkowski ◽  
Maciej Jóźwik
Keyword(s):  
Ovarian Cancer ◽  
Cervical Cancer ◽  
Reference Group ◽  
Ex Vivo ◽  
Contractile Activity ◽  
Organ Bath ◽  
Human Uterus ◽  
Uterine Contractility ◽  
Beta Adrenoceptor ◽  
Gynecological Malignancies

Objective: The aim of the study was to determine the influence of beta-adrenoceptor (ADRB) antagonists on contractile activity of the nonpregnant human uterus in patients affected by gynecological malignancies. Design: This was a controlled and prospective ex vivo study. Setting: The work was conducted as a collaboration between 4 academic departments. Materials and Methods: Myometrial specimens were obtained from women undergoing hysterectomy for benign gynecological disorders (reference group; N = 15), and ovarian (N = 15), endometrial (N = 15), synchronous ovarian-endometrial (N = 3), and cervical cancer (N = 10). Contractions of myometrial strips in an organ bath before and after applications of ADRB antagonists (propranolol, bupranolol, SR 59230A, and butoxamine) were studied under isometric conditions. Results: Propranolol and bupranolol attenuated contractions in the endometrial and cervical cancer groups similar to that in the reference group (all p < 0.05), whereas opposite effects were observed in the ovarian and synchronous ovarian-endometrial cancer groups. SR 59230A and butoxamine significantly increased contractions in the ovarian cancer group (both p < 0.001). Limitations: These results require now to be placed into a firm clinical context. Conclusions: Our study indicates that ovarian cancer considerably alters contractile activity of the nonpregnant human uterus in response to ADRB antagonists. This suggests a pathogenetic role of beta-adrenergic pathways in this malignancy. Furthermore, propranolol and bupranolol substantially influence spontaneous uterine contractility.

scholarly journals Cardioprotective Effects of PPARβ/δ Activation against Ischemia/Reperfusion Injury in Rat Heart Are Associated with ALDH2 Upregulation, Amelioration of Oxidative Stress and Preservation of Mitochondrial Energy Production

2021 ◽  
Vol 22 (12) ◽  
pp. 6399
Author(s):  
Ioanna Papatheodorou ◽  
Eleftheria Galatou ◽  
Georgios-Dimitrios Panagiotidis ◽  
Táňa Ravingerová ◽  
Antigone Lazou
Keyword(s):  
Oxidative Stress ◽  
Mrna Expression ◽  
Energy Production ◽  
Citrate Synthase ◽  
Ischemia Reperfusion Injury ◽  
Ex Vivo ◽  
Uncoupling Protein ◽  
Ischemia Reperfusion ◽  
Left Ventricular ◽  
Isocitrate Dehydrogenase 2

Accumulating evidence support the cardioprotective properties of the nuclear receptor peroxisome proliferator activated receptor β/δ (PPARβ/δ); however, the underlying mechanisms are not yet fully elucidated. The aim of the study was to further investigate the mechanisms underlying PPARβ/δ-mediated cardioprotection in the setting of myocardial ischemia/reperfusion (I/R). For this purpose, rats were treated with PPARβ/δ agonist GW0742 and/or antagonist GSK0660 in vivo and hearts were subjected to ex vivo global ischemia followed by reperfusion. PPARβ/δ activation improved left ventricular developed pressure recovery, reduced infarct size (IS) and incidence of reperfusion-induced ventricular arrhythmias while it also up-regulated superoxide dismutase 2, catalase and uncoupling protein 3 resulting in attenuation of oxidative stress as evidenced by the reduction in 4-hydroxy-2-nonenal protein adducts and protein carbonyl formation. PPARβ/δ activation also increased both mRNA expression and enzymatic activity of aldehyde dehydrogenase 2 (ALDH2); inhibition of ALDH2 abrogated the IS limiting effect of PPARβ/δ activation. Furthermore, upregulation of PGC-1α and isocitrate dehydrogenase 2 mRNA expression, increased citrate synthase activity as well as mitochondrial ATP content indicated improvement in mitochondrial content and energy production. These data provide new mechanistic insight into the cardioprotective properties of PPARβ/δ in I/R pointing to ALDH2 as a direct downstream target and suggesting that PPARβ/δ activation alleviates myocardial I/R injury through coordinated stimulation of the antioxidant defense of the heart and preservation of mitochondrial function.

scholarly journals Compared Phenolic Compound Contents of 22 Commercial Fruit and Vegetable Juices: Relationship to Ex-Vivo Vascular Reactivity and Potential In Vivo Projection

Antioxidants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 92 ◽  
Author(s):  
Alexis Matute ◽  
Jessica Tabart ◽  
Jean-Paul Cheramy-Bien ◽  
Bernard Pirotte ◽  
Claire Kevers ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Phenolic Compound ◽  
Vascular Reactivity ◽  
Ex Vivo ◽  
Clinical Investigation ◽  
Epigallocatechin Gallate ◽  
Fruit Juices ◽  
Organ Bath ◽  
Total Polyphenol ◽  
Total Anthocyanin

The real impact of polyphenol-rich vegetable and fruit juice intake on cardiovascular health remains a matter of controversy. In the present study, rat aorta segments immersed in an organ bath (OB) were used to explore whether the total polyphenol content and/or individual phenolic compound contents of 22 commercial vegetable (n = 3) and fruit juices [(citrus (n = 5), berries (n = 10), apple (n = 2), pineapple (n = 2)] might be associated with vascular tone. Red juices (particularly blackcurrant) and lemon juice caused the most marked vasorelaxation, its amplitude being endothelium dependent or not according to the volume ratio of juice to initial OB solution Vjuice/VOBS). At volume ratios 5% and 10%, both the juice and OB total polyphenol for all juices and total anthocyanin contents for berry juices significantly correlated with aorta vasorelaxation intensity. This was not the case for total or individual flavonols (except kaempferol) or for total or individual flavanols (except epigallocatechin gallate). If one relates our measured concentrations of individual phenolic compounds in OB to what is known about their physiological concentrations, and given our evidenced correlations between compound concentrations and vasorelaxation intensity, kaempferol, epigallocatechin gallate and peonidin-3-O-glucoside seem to emerge as the interesting phenolic compounds likely to be responsible for the potent vasorelaxation observed with fruit juices, and more particularly blackcurrant ones. Clinical investigation is required, however, to confirm our observations.

Luminally released serotonin stimulates colonic motility and accelerates colonic transit in rats

2007 ◽  
Vol 293 (1) ◽  
pp. R64-R69 ◽  
Author(s):  
Kiyoshi Tsukamoto ◽  
Hajime Ariga ◽  
Chris Mantyh ◽  
Theodore N. Pappas ◽  
Hidenori Yanagi ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Colonic Motility ◽  
Physiological Role ◽  
Distal Colon ◽  
Proximal Colon ◽  
Colonic Transit ◽  
Intraluminal Pressure ◽  
Ex Vivo Model ◽  
Colon Tissue ◽  
Ec Cells

Enterochromaffin (EC) cells of the epithelial cells release 5-HT into the lumen, as well as basolateral border. However, the physiological role of released 5-HT into the lumen is poorly understood. Concentrations of 5-HT in the colonic mucosa, colonic lumen, and feces were measured by HPLC in rats. To investigate whether intraluminal 5-HT accelerates colonic transit, 5-HT and 51Cr were administered into the lumen of the proximal colon, and colonic transit was measured. To investigate whether 5-HT is released into the lumen, we used an ex vivo model of isolated vascularly and luminally perfused rat proximal colon. To investigate whether luminal 5-HT is involved in regulating stress-induced colonic motility, the distal colonic motility was recorded under the stress loading, and a 5-HT3 receptor antagonist (ondansetron, 10−6 M, 0.5 ml) was administered intraluminally of the distal colon. Tissue content of 5-HT in the proximal colon (15.2 ± 4.3 ng/mg wet tissue) was significantly higher than that in the distal colon (3.3 ± 0.7 ng/mg wet tissue), while fecal content and luminal concentration of 5-HT was almost the same between the proximal and distal colon. Luminal administration of 5-HT (10−6–10−5 M) significantly accelerated colonic transit. Elevation of intraluminal pressure by 10 cmH2O significantly increased the luminal concentration of 5-HT but not the vascular concentration of 5-HT. Stress-induced stimulation of the distal colonic motility was significantly attenuated by the luminal administration of ondansetron. These results suggest that luminally released 5-HT from EC cells plays an important role in regulating colonic motility in rats.

Glucose uptake during contraction in isolated skeletal muscles from neuronal nitric oxide synthase μ knockout mice

2015 ◽  
Vol 118 (9) ◽  
pp. 1113-1121 ◽  
Author(s):  
Yet Hoi Hong ◽  
Tony Frugier ◽  
Xinmei Zhang ◽  
Robyn M. Murphy ◽  
Gordon S. Lynch ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Skeletal Muscle ◽  
Nitric Oxide Synthase ◽  
Glucose Uptake ◽  
Ex Vivo ◽  
Organ Bath ◽  
Skeletal Muscle Glucose Uptake ◽  
Nos Inhibitor ◽  
Amp Activated Protein Kinase ◽  
Oxide Synthase

Inhibition of nitric oxide synthase (NOS) significantly attenuates the increase in skeletal muscle glucose uptake during contraction/exercise, and a greater attenuation is observed in individuals with Type 2 diabetes compared with healthy individuals. Therefore, NO appears to play an important role in mediating muscle glucose uptake during contraction. In this study, we investigated the involvement of neuronal NOSμ (nNOSμ), the main NOS isoform activated during contraction, on skeletal muscle glucose uptake during ex vivo contraction. Extensor digitorum longus muscles were isolated from nNOSμ−/−and nNOSμ+/+mice. Muscles were contracted ex vivo in a temperature-controlled (30°C) organ bath with or without the presence of the NOS inhibitor NG-monomethyl-l-arginine (L-NMMA) and the NOS substrate L-arginine. Glucose uptake was determined by radioactive tracers. Skeletal muscle glucose uptake increased approximately fourfold during contraction in muscles from both nNOSμ−/−and nNOSμ+/+mice. L-NMMA significantly attenuated the increase in muscle glucose uptake during contraction in both genotypes. This attenuation was reversed by L-arginine, suggesting that L-NMMA attenuated the increase in muscle glucose uptake during contraction by inhibiting NOS and not via a nonspecific effect of the inhibitor. Low levels of NOS activity (∼4%) were detected in muscles from nNOSμ−/−mice, and there was no evidence of compensation from other NOS isoform or AMP-activated protein kinase which is also involved in mediating muscle glucose uptake during contraction. These results indicate that NO regulates skeletal muscle glucose uptake during ex vivo contraction independently of nNOSμ.

Sensitivity and reliability of zinc transporter and metallothionein gene expression in peripheral blood mononuclear cells as indicators of zinc status: responses to ex vivo zinc exposure and habitual zinc intake in humans

2020 ◽  
pp. 1-8
Author(s):  
Stephen R. Hennigar ◽  
Alyssa M. Kelley ◽  
Bradley J. Anderson ◽  
Nicholes J. Armstrong ◽  
Holly L. McClung ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Peripheral Blood Mononuclear Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Ex Vivo ◽  
Human Subjects ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells ◽  
Essential Nutrient ◽  
Zn Status

Abstract Zn is an essential nutrient for humans; however, a sensitive biomarker to assess Zn status has not been identified. The objective of this study was to determine the reliability and sensitivity of Zn transporter and metallothionein (MT) genes in peripheral blood mononuclear cells (PBMCs) to Zn exposure ex vivo and to habitual Zn intake in human subjects. In study 1, human PBMCs were cultured for 24 h with 0–50 µm ZnSO4 with or without 5 µm N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), and mRNA expression of SLC30A1-10, SLC39A1-14, MT1 subtypes (A, B, E, F, G, H, L, M and X), MT2A, MT3 and MT4 mRNA was determined. In study 2, fifty-four healthy male and female volunteers (31·9 (sd 13·8) years, BMI 25·7 (sd 2·9) kg/m2) completed a FFQ, blood was collected, PBMCs were isolated and mRNA expression of selected Zn transporters and MT isoforms was determined. Study 1: MT1E, MT1F, MT1G, MT1H, MT1L, MT1M, MT1X, MT2A and SLC30A1 increased with increasing concentrations of Zn and declined with the addition of TPEN. Study 2: Average daily Zn intake was 16·0 (sd 5·3) mg/d (range: 9–31 mg/d), and plasma Zn concentrations were 15·5 (SD 2·8) μmol/l (range 11–23 μmol/l). PBMC MT2A was positively correlated with dietary Zn intake (r 0·306, P = 0·03) and total Zn intake (r 0·382, P < 0·01), whereas plasma Zn was not (P > 0·05 for both). Findings suggest that MT2A mRNA in PBMCs reflects dietary Zn intake in healthy adults and may be a component in determining Zn status.

scholarly journals The role of mechanical forces and adenosine in the regulation of intestinal enterochromaffin cell serotonin secretion

2012 ◽  
Vol 302 (3) ◽  
pp. G397-G405 ◽  
Author(s):  
A. Chin ◽  
B. Svejda ◽  
B. I. Gustafsson ◽  
A. B. Granlund ◽  
A. K. Sandvik ◽  
...  
Keyword(s):  
Mechanical Stimulation ◽  
Tryptophan Hydroxylase ◽  
Cell Function ◽  
Cell System ◽  
Receptor Expression ◽  
Intracellular Camp ◽  
Serotonin Secretion ◽  
A2b Receptor ◽  
Ec Cells ◽  
Inflammatory Bowel

Enterochromaffin (EC) cells of the diffuse neuroendocrine cell system secrete serotonin (5-HT) with activation of gut motility, secretion, and pain. These cells express adenosine (ADORA) receptors and are considered to function as mechanosensors. Physiological pathways mediating mechanosensitivity and adenosine responsiveness remain to be fully elucidated, as do their roles in inflammatory bowel disease (IBD) and neoplasia. Pure (98–99%) FACS-sorted normal and IBD human EC cells and neoplastic EC cells (KRJ-I) were studied. IBD-EC cells and KRJ-I overexpressed ADORA2B. NECA, a general ADORA receptor agonist, stimulated, whereas the A2B receptor antagonist MRS1754 inhibited, 5-HT release (EC50 = 1.8 × 10−6 M; IC50 = 3.7 × 10−8 M), which was associated with corresponding alterations in intracellular cAMP levels and pCREB (Ser133). Mechanical stimulation using a rhythmic flex model induced transcription and activation of Tph1 (tryptophan hydroxylase) and VMAT1 (vesicular monoamine transporter 1) and the release of 5-HT, which could be inhibited by MRS1754 and amplified by NECA. Secretion was also inhibited by H-89 (PKA inhibitor) while Tph1 and VMAT1 transcription was regulated by PKA/MAPK and PI3K-mediated signaling. Normal and IBD-EC cells also responded to NECA and mechanical stimulation with PKA activation, cAMP production, and 5-HT release, effects reversible by MRS1754. EC cells express stimulatory ADORA2B, and rhythmic stretch induces A2B activation, PKA/MAPK/IP3-dependent transcription, and PKA-dependent secretion of 5-HT synthesis and secretion. Receptor expression is amplified in IBD and neoplasia, and 5-HT release is increased. Determination of factors that regulate EC cell function are necessary for understanding its role as a mechanosensory cell and to facilitate the development of agents that can selectively target cell function in EC cell-associated disease.

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