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Zizzo MG, Bellanca A, Amato A, Serio R. Opposite effects of dopamine on the mechanical activity of circular and longitudinal muscle of human colon. Neurogastroenterol Motil 2020; 32:e13811. [PMID: 32012410 DOI: 10.1111/nmo.13811] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 01/08/2020] [Accepted: 01/14/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Because dopamine (DA) has gained increasing evidence as modulator of gut motility, we aimed to characterize dopaminergic response in human colon, evaluating function and distribution of dopamine receptors in circular vs longitudinal muscle strips. METHODS Mechanical responses to DA and dopaminergic agonists on slow phasic contractions and on basal tone were examined in vitro as changes in isometric tension. RT-PCR was used to reveal the distribution of dopaminergic receptors. KEY RESULTS In spontaneous active circular muscle, DA induced an increase in the amplitude of slow phasic contractions and of the basal tone, via activation of D1-like receptors. DA contractile responses were insensitive to neural blockers or to atropine and inhibited by phospholipase C (PLC) pathway inhibitors. In precontracted circular muscle strips, DA, at the higher concentrations tested, caused a relaxant response via activation of D2-like receptors. In the longitudinal muscle, DA caused only muscular relaxation due to activation of D2-like receptors. DA relaxant responses were insensitive to neural blockers or to nitric oxide synthase inhibitor and reduced by a wide-spectrum K+ channel blockers. Transcripts encoding for all the dopaminergic receptor subtypes was observed in both circular and longitudinal preparations. CONCLUSIONS AND INFERENCES Dopamine is able to modulate contractile activity of the human colon. In the circular muscle layer, DA induces mainly muscular contraction activating non-neural D1-like receptors, coupled to PLC/IP3 pathway. In the longitudinal muscle layer, DA induces muscular relaxation acting on non-neural D2-like receptors leading to the increase in K+ conductance.
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Affiliation(s)
- Maria Grazia Zizzo
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy.,ATeN (Advanced Technologies Network) Center, University of Palermo, Palermo, Italy
| | - Annalisa Bellanca
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Antonella Amato
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
| | - Rosa Serio
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo, Italy
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Speerschneider T, Grubb S, Olesen SP, Calloe K, Thomsen MB. Ventricular repolarization time, location of pacing stimulus and current pulse amplitude conspire to determine arrhythmogenicity in mice. Acta Physiol (Oxf) 2017; 219:660-668. [PMID: 27459728 DOI: 10.1111/apha.12761] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 04/13/2016] [Accepted: 07/22/2016] [Indexed: 11/29/2022]
Abstract
AIM In this study, we investigate the impact of altered action potential durations (APD) on ventricular repolarization time and proarrhythmia in mice with and without genetic deletion of the K+ -channel-interacting protein 2 (KChIP2-/- and WT respectively). Moreover, we examine the interrelationship between the dispersion of repolarization time and current pulse amplitude in provoking ventricular arrhythmia. METHODS Intracardiac pacing in anesthetized mice determined refractory periods and proarrhythmia susceptibility. Regional activation time (AT), APD and repolarization time (=AT + APD) were measured in isolated hearts using floating microelectrodes. RESULTS Proarrhythmia in WT and KChIP2-/- was not sensitive to changes in refractory periods. Action potentials were longer in KChIP2-/- hearts compared to WT hearts. Isolated WT hearts had large apico-basal dispersion of repolarization time, whereas hearts from KChIP2-/- mice had large left-to-right ventricular dispersion of repolarization time. Pacing from the right ventricle in KChIP2-/- mice in vivo revealed significant lower current pulse amplitudes needed to induce arrhythmias in these mice. CONCLUSION Large heterogeneity of repolarization time is proarrhythmic when pacing is delivered from the location of earlier repolarization time. Ventricular repolarization time, location of the pacing stimulus and the amplitude of the stimulating current pulse are critical parameters underlying arrhythmia vulnerability.
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Affiliation(s)
- T. Speerschneider
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | - S. Grubb
- Department of Veterinary Clinical and Animal Science; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | - S. P. Olesen
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | - K. Calloe
- Department of Veterinary Clinical and Animal Science; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | - M. B. Thomsen
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
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Pokorski M, Pozdzik M, Antosiewicz J, Dymecka A, Mazzatenta A, Di Giulio C. Hypoxic Ventilatory Reactivity in Experimental Diabetes. Adv Exp Med Biol 2015; 860:123-32. [PMID: 26303474 DOI: 10.1007/978-3-319-18440-1_14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
Abstract
Diabetes, apart from generalized neuropathy and microangiopathy, involves tissue hypoxia, which may drive chronic proinflammatory state. However, studies on the ventilatory control in diabetes are sparse and conflicting. In this study we examined the function and morphology of diabetic carotid bodies (CBs). Diabetes was evoked in Wistar rats with streptozotocin (70 mg/kg, i.p.). The acute hypoxic ventilatory responses (HVR) to 12 and 8 % O(2) were investigated in conscious untreated rats after 2 and 4 weeks in a plethysmographic chamber. CBs were dissected and subjected to morphologic investigations: (1) electron transmission microscopy for ultrastructure and (2) laser scanning confocal microscopy to visualize the microvascular bed in sections labeled with the lectin Griffonia simplicifolia-I (GSI), an endothelial cell marker, and fluorescein isothiocyanate (FITC). All findings were referenced to the normal healthy rats. We found that diabetes distinctly dampened the HVR. At the ultrastructural level, the diabetic CB displayed proliferation of connective tissue and neovascularization deranging the interglomal structure, and lengthening the O(2) diffusion path from capillaries to chemoreceptor cells. The chemoreceptor cells remained largely unchanged. The endothelial cell labeling confirmed the intensive angiopathy and the induction of microvessel growth. We conclude that diabetes hampers the chemical regulation of ventilation due to remodeling of CB parenchyma, which may facilitate chronic hypoxia and inflammation in the organ.
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Abstract
AIM Gastric vagal afferents are activated in response to mechanical stimulation, an effect attenuated by neuropeptide W (NPW) in 20-week-old female mice. In this study we aimed to determine whether there were age and sex dependent effects of NPW on gastric vagal afferent mechanosensitivity. METHODS An in vitro gastro-oesophageal preparation was used to determine the effect of NPW on gastric vagal afferent mechanosensitivity from 8 and 20-week-old male and female C57BL/6 mice. Retrograde tracing and laser capture microdissection were used to selectively collect gastric vagal afferent cell bodies. Expression of NPW in the gastric mucosa and its receptor, GPR7, in gastric vagal afferent cell bodies was determined using quantitative RT-PCR. RESULTS NPW inhibited gastric tension sensitive vagal afferents from 20-week-old male and female mice, but not 8-week-old mice. In contrast, NPW inhibited the mechanosensitivity of gastric mucosal vagal afferents in 8-week-old male and female mice, but not 20-week-old mice. NPW mRNA expression in the gastric mucosa was higher in 20-week-old male mice compared to 8-week-old male mice. GPR7 mRNA expression in vagal afferent neurons innervating the gastric muscular layers was higher in 20-week-old mice compared to 8-week-old mice in both sexes. CONCLUSION The inhibitory effect of NPW on gastric tension sensitive and mucosal vagal afferents is age but not sex-dependent. These findings suggest that the physiological role of NPW varies depending on the age of the mice.
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Affiliation(s)
- Hui Li
- Vagal Afferent Research Group, Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Claudine L Frisby
- Vagal Afferent Research Group, Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Tracey A O'Donnell
- Vagal Afferent Research Group, Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Stephen J Kentish
- Vagal Afferent Research Group, Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Gary A Wittert
- Vagal Afferent Research Group, Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia; Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Amanda J Page
- Vagal Afferent Research Group, Centre for Nutrition and Gastrointestinal Diseases, Discipline of Medicine, University of Adelaide, Adelaide, South Australia, Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia; Royal Adelaide Hospital, Adelaide, South Australia, Australia.
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Mastropaolo M, Zizzo MG, Auteri M, Caldara G, Liotta R, Mulè F, Serio R. Activation of angiotensin II type 1 receptors and contractile activity in human sigmoid colon in vitro. Acta Physiol (Oxf) 2015; 215:37-45. [PMID: 26052867 DOI: 10.1111/apha.12538] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 03/30/2015] [Accepted: 06/01/2015] [Indexed: 12/15/2022]
Abstract
AIM To analyse the effects of angiotensin II (Ang II) on the contractility of human sigmoid colon, and to characterize the subtype(s) of receptor(s) involved and the related action mechanism. METHODS The contractility of sigmoid colon circular muscle strips was recorded isometrically. RT-PCR and immunohistochemistry were used to reveal the eventual existence of a local renin-angiotensin system (RAS) and the distribution of Ang II receptors. RESULTS Transcripts encoding for the Ang II type 1 (AT1 ) and the Ang II type 2 (AT2 ) receptor subtypes and for the angiotensin-converting enzyme in the whole-thickness muscular wall were observed. Ang II caused a concentration-dependent contractile response, which is antagonized by losartan, AT1 receptor antagonist, but not by PD123319, AT2 receptor antagonist. The joint application of losartan and PD123319 did not produce any additive effect. The contractile response to Ang II was partially reduced by tetrodotoxin, Na(+) voltage-gated neural channel blocker, and to some extent by SR48968, tachykinin NK2 receptor antagonist. However, hexamethonium, nicotinic receptor antagonist, atropine, cholinergic muscarinic receptor antagonist and SR140333, tachykinin NK1 receptor antagonist, were ineffective. Immunohistochemical analysis showed that AT1 receptors were expressed on the smooth muscle layers and myenteric plexus. CONCLUSION Ang II positively modulates the spontaneous contractile activity of human sigmoid colon via activation of post-junctional and pre-junctional AT1 receptors, the latter located on the enteric nerves that modulate the release of tachykinins. The presence of the components of RAS in the human colon suggests that Ang II can be also locally generated to control colonic motility.
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Affiliation(s)
- M. Mastropaolo
- Dipartimento di Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche (STEBICEF); Laboratorio di Fisiologia generale; Palermo Italy
| | - M. G. Zizzo
- Dipartimento di Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche (STEBICEF); Laboratorio di Fisiologia generale; Palermo Italy
| | - M. Auteri
- Dipartimento di Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche (STEBICEF); Laboratorio di Fisiologia generale; Palermo Italy
| | - G. Caldara
- Dipartimento di Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche (STEBICEF); Laboratorio di Fisiologia generale; Palermo Italy
| | - R. Liotta
- Pathology Service; Department of Diagnostic and Therapeutic Services; Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT); Palermo Italy
| | - F. Mulè
- Dipartimento di Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche (STEBICEF); Laboratorio di Fisiologia generale; Palermo Italy
| | - R. Serio
- Dipartimento di Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche (STEBICEF); Laboratorio di Fisiologia generale; Palermo Italy
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Locker F, Lang AA, Koller A, Lang R, Bianchini R, Kofler B. Galanin modulates human and murine neutrophil activation in vitro. Acta Physiol (Oxf) 2015; 213:595-602. [PMID: 25545502 DOI: 10.1111/apha.12444] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 12/16/2014] [Indexed: 12/27/2022]
Abstract
AIMS Polymorphonuclear neutrophils are key players in innate immunity. The innate immune system needs to be tightly controlled to ensure proper activation but also no overactivation. Galanin has been shown to regulate inflammatory reactions, and therefore, we aimed to elucidate the expression of galanin and its three receptors (GAL1 -GAL3 ) in polymorphonuclear neutrophils and to evaluate whether galanin exerts direct or indirect effects on human and murine polymorphonuclear neutrophils. METHODS Human peripheral polymorphonuclear neutrophils were isolated from fresh blood of healthy donors, and murine polymorphonuclear neutrophils were isolated from bone marrow of C57BL/6N mice. Gene expression was evaluated by qRT-PCR. As a marker for polymorphonuclear neutrophil activation, CD11b integrin surface expression was measured by FACS analysis. Furthermore, a label-free technology measuring ligand-induced dynamic mass redistribution was used to evaluate the response of polymorphonuclear neutrophils to galanin. RESULTS GAL2 receptor expression was found in both human and murine polymorphonuclear neutrophils, galanin and GAL3 receptor were exclusively expressed in murine bone marrow polymorphonuclear neutrophils, and GAL1 receptor was not detectable in polymorphonuclear neutrophils of either species. Galanin treatment was not able to induce CD11b integrin surface expression or dynamic mass redistribution in human polymorphonuclear neutrophils and murine bone marrow polymorphonuclear neutrophils. However, galanin treatment significantly enhanced the response of polymorphonuclear neutrophils of both species to interleukin-8. CONCLUSION Galanin can be regarded as an immunomodulatory peptide as it can sensitize polymorphonuclear neutrophils towards pro-inflammatory cytokines in humans and mice.
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Affiliation(s)
- F. Locker
- Laura Bassi Centre of Expertise THERAPEP; Research Program for Receptor Biochemistry and Tumor Metabolism; Department of Pediatrics; Paracelsus Medical University; Salzburg Austria
| | - A. A. Lang
- Laura Bassi Centre of Expertise THERAPEP; Research Program for Receptor Biochemistry and Tumor Metabolism; Department of Pediatrics; Paracelsus Medical University; Salzburg Austria
| | - A. Koller
- Laura Bassi Centre of Expertise THERAPEP; Research Program for Receptor Biochemistry and Tumor Metabolism; Department of Pediatrics; Paracelsus Medical University; Salzburg Austria
| | - R. Lang
- Department of Dermatology; Paracelsus Medical University; Salzburg Austria
| | - R. Bianchini
- Laura Bassi Centre of Expertise THERAPEP; Research Program for Receptor Biochemistry and Tumor Metabolism; Department of Pediatrics; Paracelsus Medical University; Salzburg Austria
| | - B. Kofler
- Laura Bassi Centre of Expertise THERAPEP; Research Program for Receptor Biochemistry and Tumor Metabolism; Department of Pediatrics; Paracelsus Medical University; Salzburg Austria
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7
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Meng N, Peng N, Huang S, Wang SQ, Zhao J, Su L, Zhang Y, Zhang S, Zhao B, Miao J. Heterogeneous nuclear ribonucleoprotein E1 regulates protein disulphide isomerase translation in oxidized low-density lipoprotein-activated endothelial cells. Acta Physiol (Oxf) 2015; 213:664-75. [PMID: 25389050 DOI: 10.1111/apha.12422] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 09/17/2014] [Accepted: 11/05/2014] [Indexed: 12/16/2022]
Abstract
AIMS Endothelium-derived protein disulphide isomerase (PDI) is required for thrombus formation in vivo. But, how to control PDI overproduction in oxidized low-density lipoprotein (oxLDL)-activated vascular endothelial cells (VECs) is not well understood. In this study, we try to answer this question using our newly identified activator of mTOC1 3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2 (3H)-one (3BDO) that has been shown to protect VECs. METHODS First, we performed a proteomics analysis on the oxLDL-activated vascular VECs in the presence or absence of 3BDO. Next, we constructed the heterogeneous nuclear ribonucleoprotein E1 (hnRNP E1) mutants at Ser43 and used the RNA-ChIP technique to investigate the relationship between hnRNP E1 and PDI production. Furthermore, we examined the effect of 3BDO on oxLDL-altered phosphorylation of Akt1 and Akt2. Finally, we studied the effect of 3BDO on oxLDL-altered PDI protein level in apolipoprotein E(-/-) mice with advanced atherosclerosis. RESULTS In VECs, oxLDL-increased PDI protein level, induced hnRNP E1 phosphorylation at Ser43, suppressed the binding of hnRNP E1 to PDI 5'UTR and induced the phosphorylation of Akt2 but not Akt1. All of these processes were blocked by 3BDO. Importantly, Ser43 mutant of hnRNP E1 inhibited the increase of PDI protein level and the decrease of the binding of hnRNP E1 and PDI 5'UTR induced by oxLDL. Furthermore, 3BDO suppressed oxLDL-induced PDI protein increase in the serum and plaque endothelium of apolipoprotein E(-/-) mice. CONCLUSION hnRNP E1 is a new regulator of PDI translation in oxLDL-activated VECs, and 3BDO is a powerful agent for controlling PDI overproduction.
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Affiliation(s)
- N. Meng
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology; School of Life Science; Shandong University; Jinan China
- School of Biological Science and Technology; University of Jinan; Jinan China
| | - N. Peng
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology; School of Life Science; Shandong University; Jinan China
| | - S. Huang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology; School of Life Science; Shandong University; Jinan China
| | - S. Q. Wang
- Institute of Organic Chemistry; School of Chemistry and Chemical Engineering; Shandong University; Jinan China
| | - J. Zhao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology; School of Life Science; Shandong University; Jinan China
| | - L. Su
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology; School of Life Science; Shandong University; Jinan China
| | - Y. Zhang
- The Key Laboratory of Cardiovascular Remodeling and Function Research; Chinese Ministry of Education and Chinese Ministry of Health; Shandong University Qilu Hospital; Jinan China
| | - S. Zhang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology; School of Life Science; Shandong University; Jinan China
| | - B. Zhao
- Institute of Organic Chemistry; School of Chemistry and Chemical Engineering; Shandong University; Jinan China
| | - J. Miao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology; School of Life Science; Shandong University; Jinan China
- The Key Laboratory of Cardiovascular Remodeling and Function Research; Chinese Ministry of Education and Chinese Ministry of Health; Shandong University Qilu Hospital; Jinan China
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Gao X, Peleli M, Zollbrecht C, Patzak A, Persson AEG, Carlström M. Adenosine A1 receptor-dependent and independent pathways in modulating renal vascular responses to angiotensin II. Acta Physiol (Oxf) 2015; 213:268-76. [PMID: 25251152 DOI: 10.1111/apha.12399] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 08/09/2014] [Accepted: 09/17/2014] [Indexed: 11/28/2022]
Abstract
AIM Renal afferent arterioles are the effector site for autoregulation of glomerular perfusion and filtration. There is synergistic interaction between angiotensin II (ANG II) and adenosine (Ado) in regulating arteriolar contraction; however, the mechanisms are not clear. In this context, this study investigated the contribution of A1 receptor-dependent and independent signalling mechanisms. METHODS Isolated perfused afferent arterioles from transgenic mice (A1 (+/+) and A1 (-/-) ) were used for vascular reactivity studies. Cultured vascular smooth muscle cells (VSMC) were used for phosphorylation studies of signalling proteins that induce arteriolar contraction. RESULTS Maximal arteriolar contraction to ANG II was attenuated in A1 (-/-) (22%) compared with A1 (+/+) (40%). Simultaneous incubation with low-dose ado (10(-8) mol L(-1) ) enhanced ANG II-induced contraction in A1 (+/+) (58%), but also in A1 (-/-) (42%). An ado transporter inhibitor (NBTI) abolished this synergistic effect in A1 (-/-) , but not in wild-type mice. Incubation with Ado + ANG II increased p38 phosphorylation in aortic VSMC from both genotypes, but treatment with NBTI only blocked phosphorylation in A1 (-/-) . Combination of ANG II + Ado also increased MLC phosphorylation in A1 (+/+) but not significantly in A1 (-/-) , and NBTI had no effects. In agreement, Ado + ANG II-induced phosphorylation of p38 and MLC in rat pre-glomerular VSMC was not affected by NBTI. However, during pharmacological inhibition of the A1 receptor simultaneous treatment with NBTI reduced phosphorylation of both p38 and MLC to control levels. CONCLUSION Interaction between ANG II and Ado in VSMC normally involves A1 receptor signalling, but this can be compensated by receptor independent actions that phosphorylate p38 MAPK and MLC.
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Affiliation(s)
- X. Gao
- Department of Medical Cell Biology; Uppsala University; Uppsala Sweden
| | - M. Peleli
- Department of Physiology & Pharmacology; Karolinska Institutet; Stockholm Sweden
| | - C. Zollbrecht
- Department of Physiology & Pharmacology; Karolinska Institutet; Stockholm Sweden
| | - A. Patzak
- Institute of Vegetative Physiology; Charité-Universitätsmedizin Berlin; Berlin Germany
| | - A. E. G. Persson
- Department of Medical Cell Biology; Uppsala University; Uppsala Sweden
| | - M. Carlström
- Department of Physiology & Pharmacology; Karolinska Institutet; Stockholm Sweden
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Sommansson A, Yamskova O, Schiöth HB, Nylander O, Sjöblom M. Long-term oral melatonin administration reduces ethanol-induced increases in duodenal mucosal permeability and motility in rats. Acta Physiol (Oxf) 2014; 212:152-65. [PMID: 24995603 DOI: 10.1111/apha.12339] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 03/26/2014] [Accepted: 07/01/2014] [Indexed: 12/20/2022]
Abstract
AIM Increased intestinal epithelial permeability is associated with intestinal inflammation and dysfunction. The aim of the present study was to investigate the role of long-term oral melatonin administration on ethanol-induced increases in duodenal mucosal permeability and hypermotility. METHODS Male Sprague-Dawley rats were administered melatonin in their tap water (0.1 mg mL(-1) or 0.5 mg mL(-1) ) for 2 or 4 weeks. After the treatment period, the rats were anaesthetized with Inactin(®) , and a 30-mm duodenal segment was perfused in situ. The effects on duodenal mucosal paracellular permeability, bicarbonate secretion, fluid flux and motor activity were studied. The expression levels of the tight junction components, zona occludens (ZO)-1, ZO-2, and ZO-3, claudin-2, claudin-3, claudin-4, occludin, and myosin light chain kinase and of the melatonin receptors MT1 and MT2 were assessed using qRT-PCR. RESULTS Melatonin administration for 2 weeks significantly reduced the basal paracellular permeability, an effect that was absent after 4 weeks. Perfusing the duodenal segment with 15% ethanol induced marked increases in duodenal paracellular permeability, bicarbonate secretion and motor activity. Melatonin for 2 weeks dose-dependently reduced ethanol-induced increases in permeability and motor activity. Four weeks of melatonin administration reduced the ethanol-induced increases in duodenal motility and bicarbonate secretion but had no effect on the increases in permeability. Two weeks of melatonin administration upregulated the expression of MT1 and MT2 , although both were downregulated after 4 weeks. Melatonin downregulated the expression of ZO-3 and upregulated the expression of claudin-2, even as all other mRNA-levels investigated were unaffected. CONCLUSION Although further studies are needed, our data demonstrate that melatonin administration markedly improves duodenal barrier functions, suggesting its utility in clinical applications when intestinal barrier functions are compromised.
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Affiliation(s)
- A. Sommansson
- Department of Neuroscience; Division of Gastrointestinal Physiology; Uppsala University; Uppsala Sweden
| | - O. Yamskova
- Department of Neuroscience; Division of Functional Pharmacology; Uppsala University; Uppsala Sweden
| | - H. B. Schiöth
- Department of Neuroscience; Division of Functional Pharmacology; Uppsala University; Uppsala Sweden
| | - O. Nylander
- Department of Neuroscience; Division of Gastrointestinal Physiology; Uppsala University; Uppsala Sweden
| | - M. Sjöblom
- Department of Neuroscience; Division of Gastrointestinal Physiology; Uppsala University; Uppsala Sweden
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10
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Navia B, Ferrer B, Giralt M, Comes G, Carrasco J, Molinero A, Quintana A, Leclerc J, Viollet B, Señarís RM, Hidalgo J. Interleukin-6 deletion in mice driven by aP2-Cre-ERT2 prevents against high-fat diet-induced gain weight and adiposity in female mice. Acta Physiol (Oxf) 2014; 211:585-96. [PMID: 24934978 DOI: 10.1111/apha.12328] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 06/10/2014] [Accepted: 06/10/2014] [Indexed: 12/21/2022]
Abstract
AIM Interleukin-6 (IL-6) is a major cytokine controlling body weight and metabolism, but because many types of cells can synthesize and respond to IL-6 considerable uncertainty still exists about the mechanisms underlying IL-6 effects. Therefore, the aim of this study was to analyse the effects of tissue-specific deletion of IL-6 using a fatty acid binding protein (aP2) promoter-Cre inducible system (aP2-Cre-ERT2). METHODS Tissue-specific IL-6 KO mice (aP2-IL-6 KO mice) were produced upon tamoxifen administration and were fed a high-fat diet (HFD, 58.4% kcal from fat) or a control diet (18%) for 14 weeks. RESULTS aP2-IL-6 KO female mice on a HFD gained less weight and adiposity than littermate wild-type mice, but these effects were not observed in males. Hypothalamic factors such as NPY and AgRP showed a pattern of expression consistent with this sex-specific phenotype. PGC-1α expression was increased in several tissues in aP2-IL-6 KO female mice, which is compatible with increased energy expenditure. Serum leptin, insulin, glucose, cholesterol and triglycerides levels were increased by HFD, and in females IL-6 deficiency reversed this effect in the case of insulin and cholesterol. HFD induced impaired responses to insulin and glucose tolerance tests, but no significant differences between genotypes were observed. CONCLUSION The present results demonstrate that deletion of IL-6 driven by aP2-Cre regulates body weight, body fat and metabolism in a sex-specific fashion.
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Affiliation(s)
- B. Navia
- Department of Physiology; Faculty of Medicine; University of Santiago de Compostela; Santiago de Compostela Spain
| | - B. Ferrer
- Department of Cellular Biology, Physiology and Immunology; Faculty of Biosciences; Institute of Neurosciences; Universitat Autònoma de Barcelona; Bellaterra Spain
| | - M. Giralt
- Department of Cellular Biology, Physiology and Immunology; Faculty of Biosciences; Institute of Neurosciences; Universitat Autònoma de Barcelona; Bellaterra Spain
| | - G. Comes
- Department of Cellular Biology, Physiology and Immunology; Faculty of Biosciences; Institute of Neurosciences; Universitat Autònoma de Barcelona; Bellaterra Spain
| | - J. Carrasco
- Department of Cellular Biology, Physiology and Immunology; Faculty of Biosciences; Institute of Neurosciences; Universitat Autònoma de Barcelona; Bellaterra Spain
| | - A. Molinero
- Department of Cellular Biology, Physiology and Immunology; Faculty of Biosciences; Institute of Neurosciences; Universitat Autònoma de Barcelona; Bellaterra Spain
| | - A. Quintana
- Department of Cellular Biology, Physiology and Immunology; Faculty of Biosciences; Institute of Neurosciences; Universitat Autònoma de Barcelona; Bellaterra Spain
| | - J. Leclerc
- Institut National de la Santé et de la Recherche Medicale (INSERM), U1016; Institut Cochin; Paris France
- CNRS UMR8104; Paris France
- Sorbonne Paris Cité; Université Paris Descartes; Paris France
| | - B. Viollet
- Institut National de la Santé et de la Recherche Medicale (INSERM), U1016; Institut Cochin; Paris France
- CNRS UMR8104; Paris France
- Sorbonne Paris Cité; Université Paris Descartes; Paris France
| | - R. M. Señarís
- Department of Physiology; Faculty of Medicine; University of Santiago de Compostela; Santiago de Compostela Spain
| | - J. Hidalgo
- Department of Cellular Biology, Physiology and Immunology; Faculty of Biosciences; Institute of Neurosciences; Universitat Autònoma de Barcelona; Bellaterra Spain
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11
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Waeckel L, Bertin F, Clavreul N, Damery T, Köhler R, Paysant J, Sansilvestri-Morel P, Simonet S, Vayssettes-Courchay C, Wulff H, Verbeuren TJ, Félétou M. Preserved regulation of renal perfusion pressure by small and intermediate conductance KCa channels in hypertensive mice with or without renal failure. Pflugers Arch 2014; 467:817-31. [DOI: 10.1007/s00424-014-1542-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 05/19/2014] [Accepted: 05/19/2014] [Indexed: 11/29/2022]
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12
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Song P, Du Y, Song W, Liu X, Hong L, Li H, Xie H, Zhou L, Tuo B, Zheng S. Bile deficiency induces changes in intestinal Cl(-) and HCO3 (-) secretions in mice. Acta Physiol (Oxf) 2014; 211:421-33. [PMID: 24731192 DOI: 10.1111/apha.12301] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 08/28/2013] [Accepted: 04/10/2014] [Indexed: 12/14/2022]
Abstract
AIMS Biliary tract obstruction is a common clinical lesion. However, the effect of biliary tract obstruction on intestinal secretion is poorly understood. In this study, we made an investigation on intestinal HCO3 (-) and Cl(-) secretions in an experimental model of murine biliary duct ligation. METHODS Murine intestinal mucosal HCO3 (-) and Cl(-) secretions were examined in vitro in Ussing chambers by pH-stat and short-circuit current (Isc ) techniques. The mRNA and protein expressions of the cystic fibrosis transmembrane conductance regulator (CFTR) and the Na(+) -K(+) -2Cl(-) cotransporter (NKCC1) were analysed by real-time PCR, western blot and immunohistochemistry. RESULTS Basal Cl(-) secretion and forskolin-stimulated duodenal and jejunal mucosal HCO3 (-) and Cl(-) secretions in mice with common biliary duct ligation were markedly elevated, compared with controls (P < 0.05 and P < 0.01). Further experiments showed that basal Cl(-) secretion and forskolin-stimulated duodenal and jejunal mucosal HCO3 (-) and Cl(-) secretions in mice with external bile drainage were also markedly elevated. CFTRinh -172 inhibited forskolin-stimulated HCO3 (-) and Cl(-) secretions. The mRNA and protein expression levels of CFTR and NKCC1 in the intestinal mucosa with both biliary duct ligation and external bile drainage were markedly higher than those in controls (P < 0.001). Bile acid administration restored the changes in function and expression of CFTR and NKCC1 in the intestinal mucosa. CONCLUSION Bile deficiency in the intestine up-regulates the expressions of intestinal mucosal CFTR and NKCC1 and enhances intestinal mucosal HCO3 (-) and Cl(-) secretion capacity, which contributes to the understanding of intestinal physiological function for patients with biliary duct obstruction.
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Affiliation(s)
- P. Song
- Key Laboratory of Combined Multi-organ Transplantation; Ministry of Public Health; First Affiliated Hospital; School of Medicine; Zhejiang University; Hangzhou 310003 China
| | - Y. Du
- Key Laboratory of Combined Multi-organ Transplantation; Ministry of Public Health; First Affiliated Hospital; School of Medicine; Zhejiang University; Hangzhou 310003 China
| | - W. Song
- Key Laboratory of Combined Multi-organ Transplantation; Ministry of Public Health; First Affiliated Hospital; School of Medicine; Zhejiang University; Hangzhou 310003 China
| | - X. Liu
- Department of Surgery; First Affiliated Hospital; School of Medicine; Zhejiang University; Hangzhou 310003 China
| | - L. Hong
- Key Laboratory of Combined Multi-organ Transplantation; Ministry of Public Health; First Affiliated Hospital; School of Medicine; Zhejiang University; Hangzhou 310003 China
| | - H. Li
- Key Laboratory of Combined Multi-organ Transplantation; Ministry of Public Health; First Affiliated Hospital; School of Medicine; Zhejiang University; Hangzhou 310003 China
| | - H. Xie
- Key Laboratory of Combined Multi-organ Transplantation; Ministry of Public Health; First Affiliated Hospital; School of Medicine; Zhejiang University; Hangzhou 310003 China
| | - L. Zhou
- Key Laboratory of Combined Multi-organ Transplantation; Ministry of Public Health; First Affiliated Hospital; School of Medicine; Zhejiang University; Hangzhou 310003 China
| | - B. Tuo
- Department of Gastroenterology; Affiliated Hospital of Zunyi Medical College; Zunyi 563003 China
| | - S. Zheng
- Key Laboratory of Combined Multi-organ Transplantation; Ministry of Public Health; First Affiliated Hospital; School of Medicine; Zhejiang University; Hangzhou 310003 China
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13
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Zheng LF, Song J, Fan RF, Chen CL, Ren QZ, Zhang XL, Feng XY, Zhang Y, Li LS, Zhu JX. The role of the vagal pathway and gastric dopamine in the gastroparesis of rats after a 6-hydroxydopamine microinjection in the substantia nigra. Acta Physiol (Oxf) 2014; 211:434-46. [PMID: 24410908 DOI: 10.1111/apha.12229] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Revised: 08/09/2013] [Accepted: 01/06/2014] [Indexed: 12/14/2022]
Abstract
AIM Gastroparesis is a common non-motor system symptom of Parkinson's disease (PD). However, the mechanism responsible for the gastric motor abnormality is not clear. We previously reported on the impaired gastric motility in 6-hydroxydopamine (6-OHDA) rats, which were treated with a bilateral microinjection of 6-OHDA in the substantia nigra (SN). We hypothesize that the enhanced dopamine system and reduced acetylcholine (Ach) in gastric tissues might contribute to the delayed gastric emptying observed in PD. METHODS A strain gauge force transducer, digital X-ray imaging system, Western blot, immunofluorescence and Radio Immunoassay were used in this study. RESULTS Dopaminergic neurones in the SN were greatly reduced following the bilateral microinjection of 6-OHDA. 6-OHDA rats exhibited impaired gastric motility and delayed gastric emptying, accompanied by increased dopamine content and the overexpression of D2 receptors in the stomach. The administration of the D2 receptor antagonist domperidone relieved gastric dysmotility in 6-OHDA rats, but the D1 receptor antagonist SCH23390 failed to do so. Subdiaphragmatic vagotomy prevented the increase in the gastric dopamine content and D2 receptor expression and improved gastric dysmotility in 6-OHDA rats. CONCLUSION Dopaminergic deficiency in the SN results in impaired gastric motility, possibly as a result of the enhanced activity of dopamine system and reduced Ach in gastric tissue. The vagus nerve plays an important role in peripheral gastric motility disorder.
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Affiliation(s)
- L.-F. Zheng
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
| | - J. Song
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
| | - R.-F. Fan
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
| | - C.-L. Chen
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
| | - Q.-Z. Ren
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
| | - X.-L. Zhang
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
| | - X.-Y. Feng
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
| | - Y. Zhang
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
| | - L.-S. Li
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
| | - J.-X. Zhu
- Department of Physiology and Pathophysiology; School of Basic Medical Sciences; Capital Medical University; Beijing China
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14
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Helle F, Dahl TD, Chatziantoniou C. A low-cost, scalable technique to study distal coronary arteriole function. Acta Physiol (Oxf) 2014; 211:260-7. [PMID: 24698112 DOI: 10.1111/apha.12293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- F. Helle
- Renal Research Group; Department of Clinical Medicine; University of Bergen; Bergen Norway
| | - T. D. Dahl
- Renal Research Group; Department of Clinical Medicine; University of Bergen; Bergen Norway
- Department of Biomedicine; University of Bergen; Bergen Norway
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15
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Zarzoso M, Mironov S, Guerrero-Serna G, Willis BC, Pandit SV. Ventricular remodelling in rabbits with sustained high-fat diet. Acta Physiol (Oxf) 2014; 211:36-47. [PMID: 24304486 DOI: 10.1111/apha.12185] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 09/02/2013] [Accepted: 10/19/2013] [Indexed: 12/23/2022]
Abstract
AIM Excess weight gain and obesity are one of the most serious health problems in the western societies. These conditions enhance risk of cardiac disease and have been linked with increased prevalence for cardiac arrhythmias and sudden death. Our goal was to study the ventricular remodelling occurring in rabbits fed with high-fat diet (HFD) and its potential arrhythmogenic mechanisms. METHODS We used 15 NZW rabbits that were randomly assigned to a control (n = 7) or HFD group (n = 8) for 18 weeks. In vivo studies included blood glucose, electrocardiographic, and echocardiographic measurements. Optical mapping was performed in Langendorff-perfused isolated hearts. RESULTS Body weight (3.69 ± 0.31 vs. 2.94 ± 0.18 kg, P < 0.001) and blood glucose levels (230 ± 61 vs. 141 ± 14 mg dL(-1) , P < 0.05) were higher in the HFD group vs. controls. The rate-corrected QT interval and its dispersion were increased in HFD rabbits vs. controls (169 ± 10 vs. 146 ± 13 ms and 37 ± 11 vs. 9 ± 2 ms, respectively; P < 0.05). Echocardiographic analysis showed morphological and functional alterations in HFD rabbits indicative of left ventricle (LV) hypertrophy. Isolated heart studies revealed no changes in repolarization and propagation properties under conditions of normal extracellular K(+) , suggesting that extrinsic factors could underlie those electrocardiographic modifications. There were no differences in the dynamics of ventricular fibrillation (frequency, wave breaks) in the presence of isoproterenol. However, HFD rabbits showed a small reduction in action potential duration and an increased incidence of arrhythmias during hyperkalaemia. CONCLUSION High-fat feeding during 18 weeks in rabbits induced a type II diabetes phenotype, LV hypertrophy, abnormalities in repolarization and susceptibility to arrhythmias during hyperkalaemia.
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Affiliation(s)
- M. Zarzoso
- Center for Arrhythmia Research; University of Michigan; Ann Arbor MI USA
- Department of Physiotherapy; Universitat de València; Valencia Spain
| | - S. Mironov
- Center for Arrhythmia Research; University of Michigan; Ann Arbor MI USA
| | - G. Guerrero-Serna
- Center for Arrhythmia Research; University of Michigan; Ann Arbor MI USA
| | - B. Cicero Willis
- Center for Arrhythmia Research; University of Michigan; Ann Arbor MI USA
| | - S. V. Pandit
- Center for Arrhythmia Research; University of Michigan; Ann Arbor MI USA
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16
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Guadalupe-Grau A, Larsen S, Guerra B, Calbet JAL, Dela F, Helge JW. Influence of age on leptin induced skeletal muscle signalling. Acta Physiol (Oxf) 2014; 211:214-28. [PMID: 24605926 DOI: 10.1111/apha.12273] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 06/03/2013] [Accepted: 03/04/2014] [Indexed: 12/27/2022]
Abstract
AIM Age associated fat mass accumulation could be because of dysregulation of leptin signalling in skeletal muscle. Thus, we investigated total protein expression and phosphorylation levels of the long isoform of the leptin receptor (OB-Rb), and leptin signalling through janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3), insulin receptor substrate 1 (IRS-1), AMP-activated protein kinase (AMPK) and acetyl-coenzyme A carboxylase (ACC), combined with the leptin signalling inhibitors suppressor of cytokine signalling 3 (SOCS3) and protein tyrosine phosphatase 1B (PTP1B) in human skeletal muscle of different age. METHODS Vastus lateralis muscle biopsies were obtained from 39 men matched for BMI < 30 kg m(-2) and separated into three groups: 13 young (Y, 24 ± 4 years); 14 middle aged (MA, 44 ± 5 years) and 12 aged (A, 58 ± 8 years) subjects. RESULTS Whole body fat percentage and plasma leptin were higher (P < 0.05), whereas lean mass, plasma free testosterone and total testosterone were lower (P < 0.05) in A compared to Y. Skeletal muscle OB-Rb (170 KDa) protein expression and pTyr(1141) -OB-R170 were comparable between groups, whereas pTyr(985) -OB-R170 was lower in A compared to Y (P < 0.05). pSTAT3 levels tended (P = 0.09) to be lower (50%) in A compared to Y. In A, muscle PTP1B was greater and IRS-1 lower than Y and MA respectively (P < 0.05). PTyr(612) -IRS-1 tended to be lower in A than in Y (P = 0.09). Suppressor of cytokine signalling 3 (SOCS3) protein expression, pJAK2, pSer(1101) -IRS-1, pAMPKα and pACCβ were similar between groups. CONCLUSION Age is associated with dysregulation of the leptin signalling and increased PTP1B protein expression in skeletal muscle.
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Affiliation(s)
- A. Guadalupe-Grau
- Department of Physical Education; University of Las Palmas de Gran Canaria; Las Palmas de Gran Canaria Spain
- Xlab; Department of Biomedical Sciences; Faculty of Health Sciences; Center for Healthy Aging; University of Copenhagen; Copenhagen Denmark
| | - S. Larsen
- Xlab; Department of Biomedical Sciences; Faculty of Health Sciences; Center for Healthy Aging; University of Copenhagen; Copenhagen Denmark
| | - B. Guerra
- Department of Clinical Sciences; Molecular and Translational Endocrinology Group; Associate Unit of University of Las Palmas de Gran Canaria and Biomedical Institute “Alberto Sols” - CSIC; Las Palmas de Gran Canaria Spain
- ICIC; Cancer Research Institute of the Canary Islands; Las Palmas de Gran Canaria Spain
- Instituto Universitario de Investigaciones Biomédicas y Sanitarias; Las Palmas de Gran Canaria Spain
| | - J. A. L. Calbet
- Department of Physical Education; University of Las Palmas de Gran Canaria; Las Palmas de Gran Canaria Spain
- Instituto Universitario de Investigaciones Biomédicas y Sanitarias; Las Palmas de Gran Canaria Spain
| | - F. Dela
- Xlab; Department of Biomedical Sciences; Faculty of Health Sciences; Center for Healthy Aging; University of Copenhagen; Copenhagen Denmark
| | - J. W. Helge
- Xlab; Department of Biomedical Sciences; Faculty of Health Sciences; Center for Healthy Aging; University of Copenhagen; Copenhagen Denmark
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17
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Lacourpaille L, Nordez A, Hug F, Couturier A, Dibie C, Guilhem G. Time-course effect of exercise-induced muscle damage on localized muscle mechanical properties assessed using elastography. Acta Physiol (Oxf) 2014; 211:135-46. [PMID: 24602146 DOI: 10.1111/apha.12272] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Revised: 10/15/2013] [Accepted: 03/03/2014] [Indexed: 01/27/2023]
Abstract
AIM Changes in muscle stiffness after exercise-induced muscle damage have been classically inferred from passive torque-angle curves. Elastographic techniques can be used to estimate the shear modulus of a localized muscular area. This study aimed to quantify the changes in shear elastic modulus in different regions of the elbow flexors after eccentric exercise and their relation to muscle length. METHODS Shear elastic modulus and transverse relaxation time (T2 ) were measured in the biceps brachii and brachialis muscles of sixteen participants, before, 1 h, 48 h and 21 days after three sets of ten maximal isokinetic eccentric contractions performed at 120° s(-1) . RESULTS The shear elastic modulus of the elbow flexors significantly increased 1 h (+46%; P = 0.005), with no significant change at 48 h and 21D, post-exercise. In contrast, T2 was not modified at 1 h but significantly increased at 48 h (+15%; P < 0.05). The increase in shear elastic modulus was more pronounced at long muscle lengths and reached a similar extent in the different regions of the elbow flexors. The normalized hysteresis area of shear elastic modulus-length relationship for the biceps brachii increased 1 h post-exercise (31%) in comparison with the pre-exercise value (18%), but was not significantly altered after five stretching cycles (P = 0.63). CONCLUSION Our results show homogeneous changes in muscle shear elastic modulus within and between elbow flexors. The greater increase in shear elastic modulus observed at long muscle lengths suggests the putative involvement of both cross-bridges number and titin in the modifications of muscle shear elastic modulus after damaging exercise.
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Affiliation(s)
- L. Lacourpaille
- Laboratory ‘Motricité, Interactions, Performance’ (EA 4334); UFR STAPS; University of Nantes; Nantes France
| | - A. Nordez
- Laboratory ‘Motricité, Interactions, Performance’ (EA 4334); UFR STAPS; University of Nantes; Nantes France
| | - F. Hug
- Laboratory ‘Motricité, Interactions, Performance’ (EA 4334); UFR STAPS; University of Nantes; Nantes France
- NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury and Health; School of Health and Rehabilitation Sciences; The University of Queensland; Brisbane Qld Australia
| | - A. Couturier
- Laboratory Sport, Expertise and Perfomance; Research and Medical Departments; French National Institute of Sport (INSEP); Paris France
| | - C. Dibie
- Laboratory Sport, Expertise and Perfomance; Research and Medical Departments; French National Institute of Sport (INSEP); Paris France
| | - G. Guilhem
- Laboratory Sport, Expertise and Perfomance; Research and Medical Departments; French National Institute of Sport (INSEP); Paris France
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18
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Cè E, Rampichini S, Limonta E, Esposito F. Fatigue effects on the electromechanical delay components during the relaxation phase after isometric contraction. Acta Physiol (Oxf) 2014; 211:82-96. [PMID: 24319999 DOI: 10.1111/apha.12212] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 08/27/2013] [Accepted: 12/03/2013] [Indexed: 12/01/2022]
Abstract
AIM By a combined electromyographic (EMG), mechanomyographic (MMG) and force (F) analysis, the electromechanical delay during muscle relaxation (R-DelayTOT ) was partitioned into electrochemical and mechanical components. The study aimed to evaluate the effects of fatigue on R-DelayTOT components and to assess their intersession and interday reliability Intraclass correlation coefficient (ICC). METHODS During tetanic stimulations, EMG, MMG and F were recorded from the human gastrocnemius medialis muscle before and after fatigue. The latency between EMG and MMG ripple cessations (R-Δt EMG-MMGR , electrochemical R-DelayTOT component); between MMG ripple cessation and F decay onset (R-Δt MMGR -F, first R-DelayTOT mechanical component); and between F decay onset and maximum MMG negative peak (R-Δt F-MMGp-p , second R-DelayTOT mechanical component) was calculated. RESULTS Before fatigue, R-Δt F-MMGp-p was the major contributor (61.9 ± 1.7 ms, 75%) to R-DelayTOT (82.7 ± 1.0 ms), while R-Δt EMG-MMGR and R-Δt MMGR -F accounted for 16% (13.3 ± 1.2 ms) and 9% (7.5 ± 1.0 ms) respectively. After fatigue, R-DelayTOT , R-Δt EMG-MMGR and R-Δt MMGR -F increased by 11, 41 and 67%, respectively (P < 0.05), whereas R-Δt F-MMGp-p did not change. Consequently, the relative contribution of R-Δt EMG-MMGR , R-Δt MMGR -F and R-Δt F-MMGp-p , to R-DelayTOT changed to 20 ± 2, 12 ± 1 and 68 ± 2% respectively. Measurement reliability was always from high to very high (ICC 0.705-0.959). CONCLUSION Fatigue altered the processes between neuromuscular activation cessation and force decay onset, but not the second mechanical component (cross-bridges detachment rate and series elastic components release). This combined approach provided reliable measurement of the different R-DelayTOT components and it may represent a valid tool to get more insights on muscle electromechanical behaviour.
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Affiliation(s)
- E. Cè
- Department of Biomedical Sciences for Health; University of Milan; Milan Italy
- Center of Sport Medicine; Don Gnocchi Foundation; Milan Italy
| | - S. Rampichini
- Department of Biomedical Sciences for Health; University of Milan; Milan Italy
- Center of Sport Medicine; Don Gnocchi Foundation; Milan Italy
| | - E. Limonta
- Department of Biomedical Sciences for Health; University of Milan; Milan Italy
| | - F. Esposito
- Department of Biomedical Sciences for Health; University of Milan; Milan Italy
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19
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Pokorski M, Takeda K, Sato Y, Okada Y. The hypoxic ventilatory response and TRPA1 antagonism in conscious mice. Acta Physiol (Oxf) 2014; 210:928-38. [PMID: 24245768 DOI: 10.1111/apha.12202] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 10/03/2013] [Accepted: 11/14/2013] [Indexed: 01/26/2023]
Abstract
AIM Recently, TRPA1 channels, richly expressed in both peripheral and central neural systems, have been proposed as novel sensors of changes in oxygen concentration along the hypoxic-hyperoxic continuum. In this study, we investigated the hypothesis that TRPA1 channels blockade should profoundly affect the hypoxic ventilatory response (HVR). METHODS We examined the chemosensory ventilatory responses in conscious mice before and after intraperitoneal administration of the specific TRPA1 antagonist HC-030031 in two doses of 50 and 200 (cumulative dose 250) mg kg(-1) . Ventilation and its responses to mild 13% and severe 7% hypoxia, pure O2 , and 5% CO2 in O2 were recorded in a whole-body plethysmograph. RESULTS TRPA1 antagonism caused a dose-dependent attenuation of the HVR. Ventilatory stimulation was virtually abrogated in response to the mild, but it remained viable, albeit slashed, at severe hypoxia after the bigger dose of HC-030031. The TRPA1 function seemed specific for the hypoxic chemoreflex as neither the response to pure O2 nor hypercapnia was appreciably influenced by the TRPA1 antagonist. CONCLUSIONS The study unravelled the role of TRPA1 in shaping the ventilatory response to low-intensity hypoxia, liable to be mediated by vagally innervated respiratory chemosensors of lower functional rank, but contradicted the TRPA1 being indispensable for the powerful carotid body chemoreflex in face of a severe hypoxic threat.
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Affiliation(s)
- M. Pokorski
- Clinical Research Centre; National Hospital Organization Murayama Medical Center; Musashimurayama City Japan
- Medical Research Center; Polish Academy of Sciences; Warsaw Poland
| | - K. Takeda
- Clinical Research Centre; National Hospital Organization Murayama Medical Center; Musashimurayama City Japan
| | - Y. Sato
- Institute of Socio-Arts and Sciences; University of Tokushima; Tokushima City Japan
| | - Y. Okada
- Clinical Research Centre; National Hospital Organization Murayama Medical Center; Musashimurayama City Japan
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20
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Sedin J, Sjöblom M, Nylander O. Prevention of duodenal ileus reveals functional differences in the duodenal response to luminal hypertonicity in Sprague-Dawley and Dark Agouti rats. Acta Physiol (Oxf) 2014; 210:573-89. [PMID: 24245737 DOI: 10.1111/apha.12201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 10/02/2013] [Accepted: 11/14/2013] [Indexed: 01/12/2023]
Abstract
AIM The mechanism by which the duodenum adjusts the luminal osmolality remains unclear. The aim was to compare the duodenal osmoregulation in response to different hyperosmolar solutions in Sprague-Dawley and Dark Agouti rats and to elucidate whether cyclooxygenase-2 inhibition affects these responses. METHODS The duodenum was perfused in situ with a 700-milliosmolar solution (NaCl alone, D-glucose ± NaCl, D-mannitol ± NaCl or orange juice), and the effects on the duodenal motility, mucosal permeability, luminal alkalinization, fluid flux and osmoregulation were assessed in anaesthetized rats. RESULTS The change in net fluid flux and luminal osmolality, in response to a given hyperosmolar solution, was almost identical in control rats of both strains. In control rats, hypertonic D-glucose-NaCl induced fluid secretion only in the presence of phlorizin, an inhibitor of SGLT1. Cyclooxygenase-2 inhibition potentiated the hypertonicity-induced fluid secretion and increased the osmolality-adjusting capability in both strains, but the responses were greater in Dark Agouti rats. While cyclooxygenase-2-inhibited Dark Agouti rats responded to the hyperosmolar solutions with depression of motility and increased mucosal permeability, these effects were absent or smaller in the Sprague-Dawley strain. In contrast, orange juice induced the same duodenal responses in cyclooxygenase-2-inhibited Dark Agouti and Sprague-Dawley rats. CONCLUSION The duodenum possesses the ability to absorb fluid despite a very high luminal osmolality. Inhibition of cyclooxygenase-2 markedly enhanced the capability of the duodenum to secrete fluid and to decrease luminal osmolality, irrespective of the hyperosmolar solution or the rat strain used, and revealed notable differences between the two strains with regard to their osmolality-adjusting capability.
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Affiliation(s)
- J. Sedin
- Division of Physiology; Department of Neuroscience; Biomedical Centre; Uppsala University; Uppsala Sweden
| | - M. Sjöblom
- Division of Physiology; Department of Neuroscience; Biomedical Centre; Uppsala University; Uppsala Sweden
| | - O. Nylander
- Division of Physiology; Department of Neuroscience; Biomedical Centre; Uppsala University; Uppsala Sweden
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21
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Yang J, Zheng X, Haugen F, Darè E, Lövdahl C, Schulte G, Fredholm BB, Valen G. Adenosine increases LPS-induced nuclear factor kappa B activation in smooth muscle cells via an intracellular mechanism and modulates it via actions on adenosine receptors. Acta Physiol (Oxf) 2014; 210:590-9. [PMID: 24119187 DOI: 10.1111/apha.12176] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 08/26/2013] [Accepted: 09/26/2013] [Indexed: 12/16/2022]
Abstract
AIM In inflamed and damaged cardiovascular tissues, local extracellular adenosine concentrations increase coincidentally with activation of the transcription factor nuclear factor kappa B (NFκB). To investigate whether adenosine influences NFκB activation in vascular smooth muscle cells (VSMCs) and, if so, to examine the role of its receptors. METHODS VSMCs were isolated from NFκB-luciferase reporter mice, cultured and then treated by lipopolysaccharide (LPS) to activate NFκB signalling. Adenosine, adenosine receptor agonists and antagonists, adenosine deaminase and uptake inhibitors were used together with LPS to evaluate the role of adenosine and its receptors on NFκB activation, which was assessed by luciferase activity and NFκB target gene expression. RESULTS Adenosine potentiated LPS-induced NFκB activation. This was dependent on adenosine uptake and enhanced by an adenosine deaminase inhibitor, suggesting that intracellular adenosine plays an important role. Non-selective adenosine receptor agonists (2Cl-Ado and NECA) inhibited NFκB activation induced by LPS. Selective A1 or A2A antagonist given alone could not completely antagonize the NECA effect, indicating that the inhibitory effect was due to multiple adenosine receptors. The activation of the A3 receptor further increased LPS-induced NFκB activation. CONCLUSIONS Adenosine increases LPS-induced nuclear factor kappa B activation in smooth muscle cells via an intracellular mechanism and decreases it via actions on A1 and A2A receptors. These results provide novel insights into the role of adenosine as a regulator of inflammation-induced NFκB activation.
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Affiliation(s)
- J. Yang
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
- Department of Molecular Medicine and Surgery; Karolinska Institutet; Stockholm Sweden
- Department of Medicine; Karolinska Institutet; Stockholm Sweden
| | - X. Zheng
- Department of Molecular Medicine and Surgery; Karolinska Institutet; Stockholm Sweden
| | - F. Haugen
- Department of Physiology; Institute of Basic Medical Science; University of Oslo; Oslo Norway
| | - E. Darè
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
- Department of Molecular Medicine and Surgery; Karolinska Institutet; Stockholm Sweden
| | - C. Lövdahl
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
| | - G. Schulte
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
| | - B. B. Fredholm
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
| | - G. Valen
- Department of Physiology; Institute of Basic Medical Science; University of Oslo; Oslo Norway
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22
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Režen T, Kovanda A, Eiken O, Mekjavic IB, Rogelj B. Expression changes in human skeletal muscle miRNAs following 10 days of bed rest in young healthy males. Acta Physiol (Oxf) 2014; 210:655-66. [PMID: 24410893 DOI: 10.1111/apha.12228] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 08/20/2013] [Accepted: 01/06/2014] [Indexed: 12/20/2022]
Abstract
AIM Studies in humans show global changes in mRNA and protein expression occur in human skeletal muscle during bed rest. As microRNAs are important regulators of expression, we analysed the global microRNA expression changes in human muscle following 10 days of sustained bed rest, with the rationale that miRNAs play key roles in atrophy of skeletal muscle. METHODS We analysed expression of miRNA and selected target proteins before and after 10 days of bed rest in biopsies obtained from the vastus lateralis muscle of 6 healthy males. RESULTS Fifteen of 152 miRNAs detected in human muscle tissue were differentially expressed, and all of them with exception of two were downregulated. The downregulated miRNAs include the following: miR-206, a myomir involved in function and maintenance of skeletal muscle; miR-23a, involved in insulin response and atrophy defence; and several members of the let-7 family involved in cell cycle, cell differentiation and glucose homeostasis. Predicted gene targets of these miRNAs are members of the MAPK, TNF receptor, ALK1, TGF-beta receptor and SMAD signalling pathways. All of these pathways were previously indicated to be involved in skeletal muscle response to physical inactivity. We also measured protein expression of selected miRNA targets and observed a decrease in HDAC4. CONCLUSION Our data demonstrate that miRNAs in postural muscles are affected by sustained inactivity and unloading, as induced by prolonged bed rest, and hence are potentially involved in regulation of skeletal muscle adjustments to inactivity. We also propose new miRNAs involved in regulation of biological processes in adult human muscle.
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Affiliation(s)
- T. Režen
- Biomedical Research Institute BRIS; Ljubljana Slovenia
| | - A. Kovanda
- Biomedical Research Institute BRIS; Ljubljana Slovenia
- Department of Biotechnology; Jozef Stefan Institute; Ljubljana Slovenia
| | - O. Eiken
- Department of Environmental Physiology; Swedish Aerospace Physiology Centre; Royal Institute of Technology; Stockholm Sweden
| | - I. B. Mekjavic
- Department of Automation, Biocybernetics and Robotics; Jozef Stefan Institute; Ljubljana Slovenia
| | - B. Rogelj
- Biomedical Research Institute BRIS; Ljubljana Slovenia
- Department of Biotechnology; Jozef Stefan Institute; Ljubljana Slovenia
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23
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Sun HJ, Zhang LL, Fan ZD, Chen D, Zhang L, Gao XY, Kang YM, Zhu GQ. Superoxide anions involved in sympathoexcitation and pressor effects of salusin-β in paraventricular nucleus in hypertensive rats. Acta Physiol (Oxf) 2014; 210:534-45. [PMID: 24304512 DOI: 10.1111/apha.12188] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 07/18/2013] [Accepted: 10/23/2013] [Indexed: 12/20/2022]
Abstract
AIMS Salusin-β in paraventricular nucleus (PVN) increases renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP), heart rate (HR) and arginine vasopressin (AVP) release in hypertensive rats but not in normal rats. The present study was designed to investigate the downstream molecular mechanism of salusin-β in the PVN in hypertension. METHOD Renovascular hypertension was induced by two-kidney, one-clip (2K1C) in male SD rats. Acute experiments were carried out 4 weeks after 2K1C or sham operation under anaesthesia. RESULTS MrgA1 mRNA expression and salusin-β level in the PVN as well as plasma salusin-β level were increased in 2K1C rats. Bilateral PVN microinjection of salusin-β increased the RSNA, MAP and HR in 2K1C rats, which were abolished by the pre-treatment with polyethylene glycol-superoxide dismutase (PEG-SOD), the superoxide anion scavenger tempol, the NAD(P)H oxidase inhibitor apocynin or the protein kinase C (PKC) inhibitor chelerythrine chloride (CLC), but not affected by the AT1 receptor antagonist losartan, the Mas receptor antagonist A-779, the NOS inhibitor L-NAME or the GABAA and GABAB receptor antagonists gabazine+CGP-35348. Salusin-β-induced increases in superoxide anion level and NAD(P)H oxidase activity in the PVN were abolished by the PVN pre-treatment with CLC. Salusin-β increased AVP levels in rostral ventrolateral medulla and plasma, which were prevented by the pre-treatment with PEG-SOD, apocynin or CLC in 2K1C rats. Salusin-β augmented the enhanced activity of PKC in the PVN in 2K1C rats. CONCLUSION Protein kinase C-NAD(P)H oxidase-superoxide anions pathway in the PVN is involved in salusin-β-induced sympathetic activation, pressor response and AVP release in renovascular hypertension.
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Affiliation(s)
- H.-J. Sun
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - L.-L. Zhang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - Z.-D. Fan
- Department of Rheumatology and Immunology; Nanjing Children's Hospital Affiliated to Nanjing Medical University; Nanjing China
| | - D. Chen
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - L. Zhang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - X.-Y. Gao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - Y.-M. Kang
- Department of Physiology and Pathophysiology; Cardiovascular Research Center; Xi'an Jiaotong University School of Medicine; Xi'an China
| | - G.-Q. Zhu
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
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24
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Sällström J, Eriksson T, Fredholm BB, Persson AEG, Palm F. Inhibition of sodium-linked glucose reabsorption normalizes diabetes-induced glomerular hyperfiltration in conscious adenosine A₁-receptor deficient mice. Acta Physiol (Oxf) 2014; 210:440-5. [PMID: 23901799 DOI: 10.1111/apha.12152] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 05/07/2013] [Accepted: 07/28/2013] [Indexed: 02/05/2023]
Abstract
AIM Glomerular hyperfiltration is commonly observed in diabetics early after the onset of the disease and predicts the progression of nephropathy. Sustained hyperglycaemia is also closely associated with kidney hypertrophy and increased electrolyte and glucose reabsorption in the proximal tubule. In this study, we investigated the role of the increased tubular sodium/glucose cotransport for diabetes-induced glomerular hyperfiltration. To eliminate any potential confounding effect of the tubuloglomerular feedback (TGF) mechanism, we used adenosine A₁-receptor deficient (A1AR(-/-)) mice known to lack a functional TGF mechanism and compared the results to corresponding wild-type animals (A1AR(+/+)). METHODS Diabetes was induced by an intravenous bolus injection of alloxan. Glomerular filtration rate (GFR) was determined in conscious mice by a single bolus injection of inulin. The sodium/glucose cotransporters were inhibited by phlorizin 30 min prior to GFR measurements. RESULTS Normoglycaemic animals had a similar GFR independent of genotype (A₁AR(+/+) 233 ± 11 vs. A₁AR(-/-) 241 ± 25 μL min(-1)), and induction of diabetes resulted in glomerular hyperfiltration in both groups (A₁AR(+/+) 380 ± 25 vs. A₁AR(-/-) 336 ± 35 μL min(-1); both P < 0.05). Phlorizin had no effect on GFR in normoglycaemic mice, whereas it reduced GFR in both genotypes during diabetes (A₁AR(+/+) 365 ± 18 to 295 ± 19, A₁AR(-/-) 354 ± 38 to 199 ± 15 μL min(-1); both P < 0.05). Notably, the reduction was more pronounced in the A₁AR(-/-) (P < 0.05). CONCLUSION This study demonstrates that increased tubular sodium/glucose reabsorption is important for diabetes-induced hyperfiltration, and that the TGF mechanism is not involved in these alterations, but rather functions to reduce any deviations from a new set-point.
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Affiliation(s)
- J. Sällström
- Department of Medical Cell Biology; Uppsala University; Uppsala Sweden
| | - T. Eriksson
- Department of Medical Cell Biology; Uppsala University; Uppsala Sweden
| | - B. B. Fredholm
- Department of Physiology and Pharmacology; Karolinska Institute; Stockholm Sweden
| | - A. E. G. Persson
- Department of Medical Cell Biology; Uppsala University; Uppsala Sweden
| | - F. Palm
- Department of Medical Cell Biology; Uppsala University; Uppsala Sweden
- Division of Drug Research; Department of Medical and Health Sciences; Center for Medical Image Science and Visualization; Linköping University; Linköping Sweden
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25
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Duelsner A, Gatzke N, Hillmeister P, Glaser J, Zietzer A, Nagorka S, Janke D, Pfitzner J, Stawowy P, Meyborg H, Urban D, Bondke Persson A, Buschmann IR. PPARγ activation inhibits cerebral arteriogenesis in the hypoperfused rat brain. Acta Physiol (Oxf) 2014; 210:354-68. [PMID: 24119262 DOI: 10.1111/apha.12179] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 09/30/2013] [Accepted: 10/01/2013] [Indexed: 11/29/2022]
Abstract
AIMS PPARγ stimulation improves cardiovascular (CV) risk factors, but without improving overall clinical outcomes. PPARγ agonists interfere with endothelial cell (EC), monocyte and smooth muscle cell (SMC) activation, function and proliferation, physiological processes critical for arterial collateral growth (arteriogenesis). We therefore assessed the effect of PPARγ stimulation on cerebral adaptive and therapeutic collateral growth. METHODS In a rat model of adaptive cerebral arteriogenesis (3-VO), collateral growth and function were assessed (i) in controls, (ii) after PPARγ stimulation (pioglitazone 2.8 mg kg(-1); 10 mg kg(-1) compared with metformin 62.2 mg kg(-1) or sitagliptin 6.34 mg kg(-1)) for 21 days or (iii) after adding pioglitazone to G-CSF (40 μg kg(-1) every other day) to induce therapeutic arteriogenesis for 1 week. Pioglitazone effects on endothelial and SMC morphology and proliferation, monocyte activation and migration were studied. RESULTS PPARγ stimulation decreased cerebrovascular collateral growth and recovery of hemodynamic reserve capacity (CVRC controls: 12 ± 7%; pio low: -2 ± 9%; pio high: 1 ± 7%; metformin: 9 ± 13%; sitagliptin: 11 ± 12%), counteracted G-CSF-induced therapeutic arteriogenesis and interfered with EC activation, SMC proliferation, monocyte activation and migration. CONCLUSION Pharmacologic PPARγ stimulation inhibits pro-arteriogenic EC activation, monocyte function, SMC proliferation and thus adaptive as well as G-CSF-induced cerebral arteriogenesis. Further studies should evaluate whether this effect may underlie the CV risk associated with thiazolidinedione use in patients.
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Affiliation(s)
- A. Duelsner
- Center for Cardiovascular Research (CCR); Richard-Thoma-Laboratories for Arteriogenesis; Charité - Universitaetsmedizin Berlin; Berlin Germany
| | - N. Gatzke
- Center for Cardiovascular Research (CCR); Richard-Thoma-Laboratories for Arteriogenesis; Charité - Universitaetsmedizin Berlin; Berlin Germany
| | - P. Hillmeister
- Center for Cardiovascular Research (CCR); Richard-Thoma-Laboratories for Arteriogenesis; Charité - Universitaetsmedizin Berlin; Berlin Germany
| | - J. Glaser
- Center for Cardiovascular Research (CCR); Richard-Thoma-Laboratories for Arteriogenesis; Charité - Universitaetsmedizin Berlin; Berlin Germany
| | - A. Zietzer
- Center for Cardiovascular Research (CCR); Richard-Thoma-Laboratories for Arteriogenesis; Charité - Universitaetsmedizin Berlin; Berlin Germany
| | - S. Nagorka
- Center for Cardiovascular Research (CCR); Richard-Thoma-Laboratories for Arteriogenesis; Charité - Universitaetsmedizin Berlin; Berlin Germany
| | - D. Janke
- Julius Wolff Institute and Berlin-Brandenburg Center for Regenerative Therapies (CVK); Charité-Universitaetsmedizin Berlin; Berlin Germany
- Institute for Chemistry and Biochemistry; FU Berlin; Berlin Germany
| | - J. Pfitzner
- Center for Cardiovascular Research (CCR); Richard-Thoma-Laboratories for Arteriogenesis; Charité - Universitaetsmedizin Berlin; Berlin Germany
| | - P. Stawowy
- Department of Internal Medicine/Cardiology; German Heart Institute Berlin (DHZB); Berlin Germany
| | - H. Meyborg
- Department of Internal Medicine/Cardiology; German Heart Institute Berlin (DHZB); Berlin Germany
| | - D. Urban
- Department of Internal Medicine/Cardiology; German Heart Institute Berlin (DHZB); Berlin Germany
| | - A. Bondke Persson
- Institute of Vegetative Physiology; Charité - Universitaetsmedizin Berlin; Berlin Germany
| | - I. R. Buschmann
- Center for Cardiovascular Research (CCR); Richard-Thoma-Laboratories for Arteriogenesis; Charité - Universitaetsmedizin Berlin; Berlin Germany
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26
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Dengler F, Rackwitz R, Benesch F, Pfannkuche H, Gäbel G. Bicarbonate-dependent transport of acetate and butyrate across the basolateral membrane of sheep rumen epithelium. Acta Physiol (Oxf) 2014; 210:403-14. [PMID: 23927569 DOI: 10.1111/apha.12155] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 06/06/2013] [Accepted: 07/30/2013] [Indexed: 12/17/2022]
Abstract
AIM This study aimed to assess the role of HCO₃⁻ in the transport of acetate and butyrate across the basolateral membrane of rumen epithelium and to identify transport proteins involved. METHODS The effects of basolateral variation in HCO₃⁻ concentrations on acetate and butyrate efflux out of the epithelium and the transepithelial flux of these short-chain fatty acids were tested in Ussing chamber experiments using (14)C-labelled substrates. HCO₃⁻-dependent transport mechanisms were characterized by adding specific inhibitors of candidate proteins to the serosal side. RESULTS Effluxes of acetate and butyrate out of the epithelium were higher to the serosal side than to the mucosal side. Acetate and butyrate effluxes to both sides of rumen epithelium consisted of HCO₃⁻-independent and -dependent parts. HCO₃⁻-dependent transport across the basolateral membrane was confirmed in studies of transepithelial fluxes. Mucosal to serosal fluxes of acetate and butyrate decreased with lowering serosal HCO₃⁻ concentrations. In the presence of 25 mm HCO₃⁻, transepithelial flux of acetate was inhibited effectively by p-hydroxymercuribenzoic acid or α-cyano-4-hydroxycinnamic acid, while butyrate flux was unaffected by the blockers. Fluxes of both acetate and butyrate from the serosal to the mucosal side were diminished largely by the addition of NO₃⁻ to the serosal side, with this effect being more pronounced for acetate. CONCLUSION Our results indicate the existence of a basolateral short-chain fatty acid/HCO₃⁻ exchanger, with monocarboxylate transporter 1 as a primary candidate for acetate transfer.
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Affiliation(s)
- F. Dengler
- Institute of Veterinary Physiology; University of Leipzig; Leipzig Germany
| | - R. Rackwitz
- Institute of Veterinary Physiology; University of Leipzig; Leipzig Germany
| | - F. Benesch
- Institute of Veterinary Physiology; University of Leipzig; Leipzig Germany
| | - H. Pfannkuche
- Institute of Veterinary Physiology; University of Leipzig; Leipzig Germany
| | - G. Gäbel
- Institute of Veterinary Physiology; University of Leipzig; Leipzig Germany
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27
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Sripetchwandee J, KenKnight SB, Sanit J, Chattipakorn S, Chattipakorn N. Blockade of mitochondrial calcium uniporter prevents cardiac mitochondrial dysfunction caused by iron overload. Acta Physiol (Oxf) 2014; 210:330-41. [PMID: 24034353 DOI: 10.1111/apha.12162] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 07/15/2013] [Accepted: 08/29/2013] [Indexed: 12/24/2022]
Abstract
AIM Iron overload in the heart can lead to iron-overload cardiomyopathy and cardiac arrhythmia. In the past decades, growing evidence has suggested that cardiac mitochondrial dysfunction is associated with the development of cardiac dysfunction and lethal arrhythmias. Despite these facts, the effect of iron overload on cardiac mitochondrial function is still unclear. In this study, we determined the effects of iron overload on the cardiac mitochondrial function and the routes of cardiac mitochondrial iron uptake. We tested the hypothesis that iron overload can lead to cardiac mitochondrial dysfunction and that mitochondrial calcium uniporter (MCU) plays a major role for cardiac mitochondrial iron uptake under iron-overload condition. Cardiac mitochondrial function was assessed via the determination of mitochondrial swelling, mitochondrial reactive oxygen species (ROS) production and mitochondrial membrane potential changes. METHODS Isolated cardiac mitochondria from male Wistar rats were used in this study. To determine the routes for cardiac mitochondrial iron uptake, isolated mitochondria were exposed to MCU blocker (Ru360), mitochondrial permeability transition pore (mPTP) blocker (cyclosporin A) and an iron chelator (deferoxamine). RESULTS We found that (i) iron overload caused cardiac mitochondrial dysfunction, indicated by increased ROS production, mitochondrial membrane depolarization and mitochondrial swelling; and (ii) only MCU blocker completely protected cardiac mitochondrial dysfunction caused by iron overload. CONCLUSIONS These findings strongly suggest that MCU could be the major route for iron uptake into cardiac mitochondria. The inhibition of MCU could be the novel pharmacological intervention for preventing iron-overload cardiomyopathy.
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Affiliation(s)
- J. Sripetchwandee
- Cardiac Electrophysiology Research and Training Center; Faculty of Medicine; Chiang Mai University; Chiang Mai Thailand
- Cardiac Electrophysiology Unit; Department of Physiology; Faculty of Medicine; Chiang Mai University; Chiang Mai Thailand
| | - S. B. KenKnight
- Cardiac Electrophysiology Research and Training Center; Faculty of Medicine; Chiang Mai University; Chiang Mai Thailand
- Cardiac Electrophysiology Unit; Department of Physiology; Faculty of Medicine; Chiang Mai University; Chiang Mai Thailand
| | - J. Sanit
- Cardiac Electrophysiology Research and Training Center; Faculty of Medicine; Chiang Mai University; Chiang Mai Thailand
- Cardiac Electrophysiology Unit; Department of Physiology; Faculty of Medicine; Chiang Mai University; Chiang Mai Thailand
| | - S. Chattipakorn
- Cardiac Electrophysiology Research and Training Center; Faculty of Medicine; Chiang Mai University; Chiang Mai Thailand
- Faculty of Dentistry; Chiang Mai University; Chiang Mai Thailand
| | - N. Chattipakorn
- Cardiac Electrophysiology Research and Training Center; Faculty of Medicine; Chiang Mai University; Chiang Mai Thailand
- Cardiac Electrophysiology Unit; Department of Physiology; Faculty of Medicine; Chiang Mai University; Chiang Mai Thailand
- Biomedical Engineering Center; Chiang Mai University; Chiang Mai Thailand
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28
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Goosse K, Bouckenooghe T, Sisino G, Aurientis S, Remacle C, Reusens B. Increased susceptibility to streptozotocin and impeded regeneration capacity of beta-cells in adult offspring of malnourished rats. Acta Physiol (Oxf) 2014; 210:99-109. [PMID: 23701924 DOI: 10.1111/apha.12121] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 02/22/2013] [Accepted: 05/16/2013] [Indexed: 01/06/2023]
Abstract
BACKGROUND Epidemiological studies related poor maternal nutrition and subsequent growth retardation in the progeny to the development of diabetes later in life. Low-protein diet during gestation altered the beta-cell development of the rat progeny by decreasing beta-cell proliferation and increasing their sensitivity to nitric oxide and cytokines in the foetus. This disturbed maternal environment had long-lasting consequences because the higher beta-cell vulnerability was maintained at adulthood. AIM The aim of this study was to determine whether early malnutrition influences the vulnerability and the regeneration capacity of beta-cells after streptozotocin (STZ) damage at adulthood. METHODS Gestating rats were fed either a control or a low-protein diet until weaning. Adult female offspring received injections of Freund's adjuvant weekly for 5 weeks followed 24 h later by STZ. Half of the cohort was killed at d34, whereas the other half was maintained until d48 to analyse the regeneration capacity of the beta-cells. RESULTS Although control and low-protein rats had equivalent pancreatic insulin content and beta-cell volume density at d34, hyperglycaemia appeared earlier and was more dramatic in low-protein rats than in control rats. STZ treatment increased beta-cell proliferation similarly in both groups. At d48, apoptotic rate was higher in the low-protein group. Regeneration appeared in control, but not in the low-protein rats, where beta-cell aggregates/surface area and Reg1-positive area were decreased compared to control. CONCLUSION Maternal malnutrition programmes a more vulnerable endocrine pancreas in the progeny which is unable to regenerate after injury, therefore predisposing it to develop glucose intolerance and diabetes later in life.
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Affiliation(s)
- K. Goosse
- Laboratory of Cell Biology; Université catholique de Louvain; Louvain-la-Neuve Belgium
| | - T. Bouckenooghe
- Laboratory of Cell Biology; Université catholique de Louvain; Louvain-la-Neuve Belgium
- EA 4489 “Environnement périnatal et croissance”; Faculté de Médecine; H Warembourg; Lille France
| | - G. Sisino
- EA 4489 “Environnement périnatal et croissance”; Faculté de Médecine; H Warembourg; Lille France
| | - S. Aurientis
- EA 4489 “Environnement périnatal et croissance”; Faculté de Médecine; H Warembourg; Lille France
| | - C. Remacle
- Laboratory of Cell Biology; Université catholique de Louvain; Louvain-la-Neuve Belgium
| | - B. Reusens
- Laboratory of Cell Biology; Université catholique de Louvain; Louvain-la-Neuve Belgium
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Castañeda-Gutiérrez E, Moser M, García-Ródenas C, Raymond F, Mansourian R, Rubio-Aliaga I, Viguet-Carrin S, Metairon S, Ammon-Zufferey C, Avanti-Nigro O, Macé K, Silva-Zolezzi I. Effect of a mixture of bovine milk oligosaccharides, Lactobacillus rhamnosus NCC4007 and long-chain polyunsaturated fatty acids on catch-up growth of intra-uterine growth-restricted rats. Acta Physiol (Oxf) 2014; 210:161-73. [PMID: 23834457 DOI: 10.1111/apha.12145] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 02/15/2013] [Accepted: 07/02/2013] [Indexed: 12/21/2022]
Abstract
AIM To investigate the effect of a nutritional mixture (bovine milk oligosaccharides, Lactobacillus rhamnosus NCC4007, arachidonic and docosahexaenoic acid) on growth of intrauterine growth-restricted (IUGR) rats. METHODS IUGR was induced by maternal food restriction. The offspring (males and females) were assigned to: REF (non-IUGR, no mixture), IUGRc (IUGR, no mixture), or IUGRmx (IUGR, mixture). The mixture was given from day 7 to day 58, when tissues and plasma from half of the animals were collected for hormones, metabolites and microarray analysis. The rest received a high-fat diet (HFD) until day 100. Glucose tolerance was measured at 56 and 98 days, and body fat content at 21, 52 and 97 days. RESULTS IUGRmx had the greatest growth during lactation, but from day 22 to day 54, both IUGR groups gained less body weight than the REF (P < 0.05). In the short-term (58 days), IUGRmx tended to be longer (P = 0.06) and had less body fat (P = 0.03) than IUGRc. These differences were not seen after HFD. Microarray analysis of hepatic mRNA expression at 58 and 100 days revealed a gender-dependent treatment effect, and expression of genes related to lipid metabolism was the most affected. Twelve of these genes were selected for studying differences in DNA methylation in the promoter region, for some, we observed age- and gender-related differences but none because of treatment. CONCLUSION The nutritional intervention promoted catch-up growth and normalized excessive adiposity in IUGR animals at short-term. The benefits did not extend after a period of HFD. IUGR and early diet had gender-dependent effects on hepatic gene expression.
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Affiliation(s)
| | - M. Moser
- Department of Bioanalytical Sciences; Nestlé Research Center; Lausanne Switzerland
| | - C. García-Ródenas
- Department of Nutrition and Health; Nestlé Research Center; Lausanne Switzerland
| | - F. Raymond
- Department of Bioanalytical Sciences; Nestlé Research Center; Lausanne Switzerland
| | - R. Mansourian
- Department of Bioanalytical Sciences; Nestlé Research Center; Lausanne Switzerland
| | - I. Rubio-Aliaga
- Department of Bioanalytical Sciences; Nestlé Research Center; Lausanne Switzerland
| | - S. Viguet-Carrin
- Department of Nutrition and Health; Nestlé Research Center; Lausanne Switzerland
| | - S. Metairon
- Department of Bioanalytical Sciences; Nestlé Research Center; Lausanne Switzerland
| | - C. Ammon-Zufferey
- Department of Nutrition and Health; Nestlé Research Center; Lausanne Switzerland
| | - O. Avanti-Nigro
- Department of Nutrition and Health; Nestlé Research Center; Lausanne Switzerland
| | - K. Macé
- Department of Nutrition and Health; Nestlé Research Center; Lausanne Switzerland
| | - I. Silva-Zolezzi
- Department of Bioanalytical Sciences; Nestlé Research Center; Lausanne Switzerland
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30
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Kjaergaard M, Nilsson C, Rosendal A, Nielsen MO, Raun K. Maternal chocolate and sucrose soft drink intake induces hepatic steatosis in rat offspring associated with altered lipid gene expression profile. Acta Physiol (Oxf) 2014; 210:142-53. [PMID: 23782871 DOI: 10.1111/apha.12138] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 03/01/2013] [Accepted: 06/13/2013] [Indexed: 12/11/2022]
Abstract
AIM According to the World Diabetes Foundation, there is an urgent need to investigate the impact of maternal health and nutrition during pregnancy to understand the background for the accelerating incidence of obesity and type 2 diabetes. In this study, we specifically concentrated on the role of overfeeding during different developmental periods. METHODS Sprague-Dawley rats were offered chow or high-fat/high-sucrose diet (chow plus chocolate and soft drink) during gestation and lactation. At birth, offspring were randomly cross-fostered within each dietary group into small and normal litter sizes until weaning, giving four dietary groups. RESULTS At postnatal day 1, offspring from high-fat/high-sucrose-fed dams were heavier and had increased hepatic triglycerides (TG), hepatic glycogen, blood glucose and plasma insulin compared with offspring from chow-fed dams. Hepatic genes involved in lipid oxidation, VLDL transport and insulin receptor were down-regulated, whereas FGF21 expression was up-regulated. Independent of postnatal litter size, offspring from high-fat/high-sucrose-fed dams aged 21 days had still increased hepatic TG and up-regulated FGF21 expression, while plasma insulin started to decrease. Litter size reduction in offspring from high-fat/high-sucrose-fed dams further increased body weight and adiposity, and up-regulated genes involved in hepatic mitochondrial lipid oxidation and VLDL transport compared with all other groups. Litter size reduction did not have any impact on body weight gain and adiposity in offspring born to chow-fed dams. CONCLUSION Our results suggest that supplementation of chocolate and soft drink during gestation and lactation contributes to early onset of hepatic steatosis associated with changes in hepatic gene expression and lipid handling.
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Affiliation(s)
- M. Kjaergaard
- Department of Type 2 Diabetes Pharmacology; Novo Nordisk A/S; Maaloev Denmark
- Department of Veterinary Clinical and Animal Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Frederiksberg Denmark
| | - C. Nilsson
- Uppsala University Innovation, Uppsala Science Park; Uppsala Sweden
| | - A. Rosendal
- Department of Assay Technology; Novo Nordisk A/S; Maaloev Denmark
| | - M. O. Nielsen
- Department of Veterinary Clinical and Animal Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Frederiksberg Denmark
| | - K. Raun
- Department of Type 2 Diabetes Pharmacology; Novo Nordisk A/S; Maaloev Denmark
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da Silva Aragão R, Guzmán-Quevedo O, Pérez-García G, Toscano AE, Gois Leandro C, Manhães-de-Castro R, Bolaños-Jiménez F. Differential developmental programming by early protein restriction of rat skeletal muscle according to its fibre-type composition. Acta Physiol (Oxf) 2014; 210:70-83. [PMID: 23362831 DOI: 10.1111/apha.12073] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 11/13/2012] [Accepted: 01/25/2013] [Indexed: 12/29/2022]
Abstract
AIMS Differences in fibre-type composition of skeletal muscle have been associated with obesity and insulin resistance. As a poor nutrient environment early in life is a predisposing factor for the development of obesity and related metabolic diseases at adulthood, this study aimed at determining the long-term consequences of maternal undernutrition on the structural and metabolic properties of two skeletal muscles characterized by their different fibre-type composition and metabolic properties. METHODS The fibre-type composition and enzymatic activities of hexokinase (HK), beta-hydroxyacyl-CoA dehydrogenase (β-HAD) and citrate synthase (CS) were measured in soleus and extensor digitorum longus (EDL) muscles from adult rats born to dams fed a control (17% protein) or a low-protein [8% protein (PR)] diet throughout pregnancy and lactation. In addition, the expression levels of several genes regulating glycolysis, fatty acid oxidation and mitochondrial biogenesis were determined by real-time PCR. RESULTS Protein rats exhibited enhanced density of type II fibres along with decreased rate of fatty acid oxidation and glycolysis in soleus but not EDL. Malnourished rats exhibited also a different gene expression profile in soleus and EDL. Altogether, these alterations correspond to a state of energy deficiency and are present in animals which do not show yet any sign of obesity or glucose intolerance. CONCLUSION We conclude that maternal protein restriction alters in the long term the structural and enzymatic properties of offspring skeletal muscle in a fibre-type-dependent manner. These alterations might have a causative role in the development of obesity and related metabolic disorders later in life.
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Affiliation(s)
- R. da Silva Aragão
- INRA; UMR1280 Physiologie des Adaptations Nutritionnelles; Nantes France
- Université de Nantes; Nantes Atlantique Université; Nantes France
- Departamento de Nutrição; Centro de Ciências da Saúde; Universidade Federal de Pernambuco; Recife Brazil
| | - O. Guzmán-Quevedo
- INRA; UMR1280 Physiologie des Adaptations Nutritionnelles; Nantes France
- Université de Nantes; Nantes Atlantique Université; Nantes France
| | - G. Pérez-García
- INRA; UMR1280 Physiologie des Adaptations Nutritionnelles; Nantes France
- Université de Nantes; Nantes Atlantique Université; Nantes France
| | - A. E. Toscano
- Núcleo de Enfermagem; CAV; Universidade Federal de Pernambuco; Vitória de Santo Antão Brazil
| | - C. Gois Leandro
- Núcleo de Educação Física e Ciências do Esporte; CAV; Universidade Federal de Pernambuco; Vitória de Santo Antão Brazil
| | - R. Manhães-de-Castro
- Departamento de Nutrição; Centro de Ciências da Saúde; Universidade Federal de Pernambuco; Recife Brazil
| | - F. Bolaños-Jiménez
- INRA; UMR1280 Physiologie des Adaptations Nutritionnelles; Nantes France
- Université de Nantes; Nantes Atlantique Université; Nantes France
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Eriksson JG, Kajantie E, Lampl M, Osmond C, Barker DJP. Small head circumference at birth and early age at adiposity rebound. Acta Physiol (Oxf) 2014; 210:154-60. [PMID: 23796386 DOI: 10.1111/apha.12142] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 01/09/2013] [Accepted: 06/17/2013] [Indexed: 02/02/2023]
Abstract
AIMS The adiposity rebound is the age in childhood when body mass index is at a minimum before increasing again. The age at rebound is highly variable. An early age is associated with increased obesity in later childhood and adult life. We have reported that an early rebound is predicted by low weight gain between birth and 1 year of age and resulting low body mass index at 1 year. Here, we examine whether age at adiposity rebound is determined by influences during infancy or is a consequence of foetal growth. Our hypothesis was that measurements of body size at birth are related to age at adiposity rebound. METHODS Longitudinal study of 2877 children born in Helsinki, Finland, during 1934-1944. RESULTS Early age at adiposity rebound was associated with small head circumference and biparietal diameter at birth, but not with other measurements of body size at birth. The mean age at adiposity rebound rose from 5.8 years in babies with a head circumference of ≤33 cm to 6.2 in babies with a head circumference of >36 cm (P for trend = 0.007). The association between thinness in infancy and early rebound became apparent at 6 months of age. It was not associated with adverse living conditions. In a simultaneous regression, small head circumference at birth, high mother's body mass index and tall maternal stature each had statistically significant trends with early adiposity rebound (P = 0.002, <0.001, 0.004). CONCLUSION We hypothesize that the small head size at birth that preceded an early adiposity rebound was the result of inability to sustain a rapid intra-uterine growth trajectory initiated in association with large maternal body size. This was followed by catch-up growth in infancy, and we hypothesize that this depleted the infant's fat stores.
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Affiliation(s)
- J. G. Eriksson
- Department of Chronic Disease Prevention; National Institute for Health and Welfare; Helsinki Finland
- Department of General Practice and Primary Health Care; University of Helsinki; Helsinki Finland
- Vasa Central Hospital; Vasa Finland
- Folkhälsan Research Centre; Helsingfors Universitet; Helsinki Finland
- Unit of General Practice; Helsinki University Central Hospital; Helsinki Finland
| | - E. Kajantie
- Department of Chronic Disease Prevention; National Institute for Health and Welfare; Helsinki Finland
- Hospital for Children and Adolescents; Helsinki University Central Hospital and University of Helsinki; Helsinki Finland
| | - M. Lampl
- Center for the Study of Human Health; Emory University; Atlanta GA USA
| | - C. Osmond
- MRC Lifecourse Epidemiology Unit; University of Southampton; Southampton General Hospital; Southampton UK
| | - D. J. P. Barker
- MRC Lifecourse Epidemiology Unit; University of Southampton; Southampton General Hospital; Southampton UK
- Chair of Fetal Programming; King Saud University; Riyadh Saudi Arabia
- Oregon Health and Science University; Heart Research Center; Portland OR USA
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Speerschneider T, Thomsen MB. Physiology and analysis of the electrocardiographic T wave in mice. Acta Physiol (Oxf) 2013; 209:262-71. [PMID: 24119104 DOI: 10.1111/apha.12172] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Revised: 08/20/2013] [Accepted: 09/24/2013] [Indexed: 01/28/2023]
Abstract
AIM The murine electrocardiogram (ECG) is a valuable tool in cardiac research, although the definition of the T wave has been a matter of debate for several years potentially leading to incomparable data. By this study, we seek to make a clear definition of the murine T wave. Moreover, we investigate the consequences of performing QT interval correction in anaesthetized mice. METHODS Electrocardiograms from conscious mice were recorded by implanted telemetry devices. Surface ECGs were recorded from anaesthetized mice before and during pharmacological interventions, ventricular ischaemia and heart failure. Right atrial pacing was performed to evaluate the relationship between heart rate and QT intervals. RESULTS Electrocardiogram traces of conscious and anaesthetized mice (lead II) showed separable positive J waves and negative T waves. The end of the T wave was determined as the point where the T wave returned to the isoelectric line. Atrial pacing revealed that the duration of the QT interval is independent of heart rate in anaesthetized mice. The calcium channel blocker, verapamil, prolonged the PR interval; however, the polarities of the J and T waves were not changed. Local cardiac ischaemia and β-adrenergic stimulation caused indistinguishable positive J and T waves. In contrast, chronic heart failure caused entirely negative J and T waves. In every case, the end of the T wave was clearly distinguishable on the ECG. CONCLUSION The end of the T wave is readily available from conscious and anaesthetized mice. Heart rate correction of QT interval duration in the anaesthetized mouse is not recommended.
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Affiliation(s)
- T. Speerschneider
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; Danish National Research Foundation Centre for Cardiac Arrhythmia; University of Copenhagen; Copenhagen Denmark
| | - M. B. Thomsen
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; Danish National Research Foundation Centre for Cardiac Arrhythmia; University of Copenhagen; Copenhagen Denmark
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Hussain A, Nookaew I, Khoomrung S, Andersson L, Larsson I, Hulthén L, Jansson N, Jakubowicz R, Nilsson S, Sandberg AS, Nielsen J, Holmäng A. A maternal diet of fatty fish reduces body fat of offspring compared with a maternal diet of beef and a post-weaning diet of fish improves insulin sensitivity and lipid profile in adult C57BL/6 male mice. Acta Physiol (Oxf) 2013; 209:220-34. [PMID: 23746286 DOI: 10.1111/apha.12130] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 01/20/2013] [Accepted: 05/31/2013] [Indexed: 01/22/2023]
Abstract
AIM The maternal diet during pregnancy and lactation may affect the long-term health of the offspring. Our aim was to study how a fish or meat diet perinatal and after weaning affects body composition, insulin sensitivity and the profile of n-3 and n-6 polyunsaturated fatty acids (PUFAs) in breast milk, fat depots, skeletal muscle and liver in male adult mice offspring. METHODS During gestation and lactation, C57BL/6 dams were fed a herring- or beef-based diet. Half of the pups in each group changed diets after weaning. In offspring, body composition measured by DEXA, plasma lipid profile and insulin sensitivity measured by euglycemic clamp or QUICKI were monitored to adulthood. Analysis of total FAs by GC-MS were performed in the diet, breast milk and in different tissues. RESULTS At 9 week of age, offspring of herring-fed dams had less body fat than offspring of beef-fed dams. Mice fed herring after weaning had increased insulin sensitivity at 15 week of age, reduced total plasma cholesterol and triglyceride levels, and compared with beef-fed mice, larger interscapular brown adipose tissue depots. The FA composition of the maternal diet was mirrored in breast milk, and the herring diet significantly affected the FA profile of different tissues, leading to an increased content of n-3 PUFAs. CONCLUSION A herring-based maternal diet reduces body fat in the offspring, but the insulin sensitivity, plasma lipids and amount of brown adipose tissue are affected by the offspring's own diet; the herring diet is more beneficial than the beef diet.
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Affiliation(s)
- A. Hussain
- Department of Physiology; Institute of Neuroscience and Physiology; The Sahlgrenska Academy; University of Gothenburg; Gothenburg; Sweden
| | - I. Nookaew
- Department of Chemical and Biological Engineering; Systems Biology; Chalmers University of Technology; Gothenburg; Sweden
| | - S. Khoomrung
- Department of Chemical and Biological Engineering; Systems Biology; Chalmers University of Technology; Gothenburg; Sweden
| | - L. Andersson
- Department of Physiology; Institute of Neuroscience and Physiology; The Sahlgrenska Academy; University of Gothenburg; Gothenburg; Sweden
| | - I. Larsson
- Department of Endocrinology, Diabetology and Metabolism; Sahlgrenska University Hospital; Gothenburg; Sweden
| | - L. Hulthén
- Department of Internal Medicine and Clinical Nutrition; Institute of Medicine; The Sahlgrenska Academy, University of Gothenburg; Gothenburg; Sweden
| | - N. Jansson
- Department of Physiology; Institute of Neuroscience and Physiology; The Sahlgrenska Academy; University of Gothenburg; Gothenburg; Sweden
| | - R. Jakubowicz
- Department of Physiology; Institute of Neuroscience and Physiology; The Sahlgrenska Academy; University of Gothenburg; Gothenburg; Sweden
| | - S. Nilsson
- Department of Mathematical Statistics; Chalmers University of Technology; Gothenburg; Sweden
| | - A.-S. Sandberg
- Department of Chemical and Biological Engineering; Food Science; Chalmers University of Technology; Gothenburg; Sweden
| | - J. Nielsen
- Department of Chemical and Biological Engineering; Systems Biology; Chalmers University of Technology; Gothenburg; Sweden
| | - A. Holmäng
- Department of Physiology; Institute of Neuroscience and Physiology; The Sahlgrenska Academy; University of Gothenburg; Gothenburg; Sweden
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Li H, Kentish SJ, Kritas S, Young RL, Isaacs NJ, O'Donnell TA, Blackshaw LA, Wittert GA, Page AJ. Modulation of murine gastric vagal afferent mechanosensitivity by neuropeptide W. Acta Physiol (Oxf) 2013; 209:179-91. [PMID: 23927541 DOI: 10.1111/apha.12154] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 06/09/2013] [Accepted: 07/31/2013] [Indexed: 12/22/2022]
Abstract
AIM Neuropeptide W (NPW) is an endogenous ligand for the receptors GPR7 and GPR8 and is involved in central regulation of energy homeostasis. NPW in the periphery is found in gastric gastrin (G) cells. In the stomach, energy intake is influenced by vagal afferent signals, so we aimed to determine the effect of NPW on mechanosensitive gastric vagal afferents under different feeding conditions. METHODS Female C57BL/6 mice (N > 10 per group) were fed a standard laboratory diet (SLD), high-fat diet (HFD) or were food restricted. The relationship between NPW immunopositive cells and gastric vagal afferent endings was determined by anterograde tracing and NPW immunohistochemistry. An in vitro gastro-oesophageal preparation was used to determine the functional effects of NPW on gastric vagal afferents. Expression of NPW in the gastric mucosa and GPR7 in whole nodose ganglia was determined by quantitative RT-PCR (QRT-PCR). The expression of GPR7 in gastric vagal afferent neurones was determined by retrograde tracing and QRT-PCR. RESULTS Neuropeptide W immunoreactive cells were found in close proximity to traced vagal afferents. NPW selectively inhibited responses of gastric vagal tension receptors to stretch in SLD but not HFD or fasted mice. In the nodose ganglia, GPR7 mRNA was specifically expressed in gastric vagal afferent neurones. In fasted mice gastric mucosal NPW and nodose GPR7, mRNA was reduced compared with SLD. A HFD had no effect on gastric NPW mRNA, but down-regulated nodose GPR7 expression. CONCLUSION Neuropeptide W modulates gastric vagal afferent activity, but the effect is dynamic and related to feeding status.
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Affiliation(s)
- H. Li
- Nerve-Gut Research Laboratory; University of Adelaide; Adelaide; Australia
| | - S. J. Kentish
- Nerve-Gut Research Laboratory; University of Adelaide; Adelaide; Australia
| | - S. Kritas
- Women's & Children's Hospital; University of Adelaide; Adelaide; Australia
| | | | - N. J. Isaacs
- Nerve-Gut Research Laboratory; University of Adelaide; Adelaide; Australia
| | | | - L. A. Blackshaw
- Wingate Institute of Neurogastroenterology; Blizard Institute; Barts and The London School of Medicine & Dentistry; Queen Mary, University of London; London; UK
| | - G. A. Wittert
- Nerve-Gut Research Laboratory; University of Adelaide; Adelaide; Australia
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Eckberg DL, Cooke WH, Diedrich A, Levine BD, Pawelczyk JA, Buckey JC, Ertl AC, Biaggioni I, Cox JF, Robertson D, Baisch FJ, Blomqvist CG, Kuusela TA, Tahvanainen KUO. Human baroreflex rhythms persist during handgrip and muscle ischaemia. Acta Physiol (Oxf) 2013; 209:114-23. [PMID: 23809494 DOI: 10.1111/apha.12143] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 05/20/2013] [Accepted: 06/20/2013] [Indexed: 12/20/2022]
Abstract
AIM To determine whether physiological, rhythmic fluctuations of vagal baroreflex gain persist during exercise, post-exercise ischaemia and recovery. METHODS We studied responses of six supine healthy men and one woman to a stereotyped protocol comprising rest, handgrip exercise at 40% maximum capacity to exhaustion, post-exercise forearm ischaemia and recovery. We measured electrocardiographic R-R intervals, photoplethysmographic finger arterial pressures and peroneal nerve muscle sympathetic activity. We derived vagal baroreflex gains from a sliding (25-s window moved by 2-s steps) systolic pressure-R-R interval transfer function at 0.04-0.15 Hz. RESULTS Vagal baroreflex gain oscillated at low, nearly constant frequencies throughout the protocol (at approx. 0.06 Hz - a period of about 18 s); however, during exercise, most oscillations were at low-gain levels, and during ischaemia and recovery, most oscillations were at high-gain levels. CONCLUSIONS Vagal baroreflex rhythms are not abolished by exercise, and they are not overwhelmed after exercise during ischaemia and recovery.
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Affiliation(s)
| | - W. H. Cooke
- Health and Kinesiology; University of Texas at San Antonio; San Antonio; TX; USA
| | - A. Diedrich
- Department of Medicine; Division of Clinical Pharmacology; Autonomic Dysfunction Center; Vanderbilt University; Nashville; TN; USA
| | - B. D. Levine
- Internal Medicine; University of Texas Southwestern Medical Center at Dallas; Dallas; TX; USA
| | - J. A. Pawelczyk
- The Pennsylvania State University; University Park and Hershey; PA; USA
| | - J. C. Buckey
- Dartmouth Hitchcock Medical Center; Lebanon; NH; USA
| | - A. C. Ertl
- Department of Medicine; Division of Clinical Pharmacology; Autonomic Dysfunction Center; Vanderbilt University; Nashville; TN; USA
| | - I. Biaggioni
- Department of Medicine; Division of Clinical Pharmacology; Autonomic Dysfunction Center; Vanderbilt University; Nashville; TN; USA
| | | | - D. Robertson
- Department of Medicine; Division of Clinical Pharmacology; Autonomic Dysfunction Center; Vanderbilt University; Nashville; TN; USA
| | - F. J. Baisch
- DLR-Institute for Aerospace Medicine; Cologne; Germany
| | - C. G. Blomqvist
- Internal Medicine; University of Texas Southwestern Medical Center at Dallas; Dallas; TX; USA
| | - T. A. Kuusela
- Department of Physics; Turku University; Turku; Finland
| | - K. U. O. Tahvanainen
- Department of Clinical Physiology and Nuclear Medicine; South Karelia Central Hospital; Lappeenranta; Finland
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Kawada T, Akiyama T, Shimizu S, Kamiya A, Uemura K, Turner MJ, Shirai M, Sugimachi M. Sympathetic afferent stimulation inhibits central vagal activation induced by intravenous medetomidine in rats. Acta Physiol (Oxf) 2013; 209:55-61. [PMID: 23710753 DOI: 10.1111/apha.12123] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 05/08/2013] [Accepted: 05/21/2013] [Indexed: 11/29/2022]
Abstract
AIM To examine whether sympathetic afferent stimulation (SAS) inhibits central vagal activation induced by α2 -adrenergic stimulation. METHODS In anaesthetized Wistar-Kyoto rats, a cardiac microdialysis technique was applied to the left ventricle, and the effect of α2 -adrenergic stimulation by medetomidine on myocardial interstitial acetylcholine (ACh) levels was examined in the absence (n = 6) or the presence (n = 6) of SAS delivered from the left stellate ganglion. The effect of electrical vagal efferent stimulation on myocardial interstitial ACh release was also examined in the absence or the presence of SAS (n = 6). RESULTS Intravenous medetomidine (0.1 mg kg(-1) ) significantly increased myocardial interstitial ACh levels in the absence of SAS (from 1.95 ± 0.79 to 3.36 ± 1.61 nM, P < 0.05), but not in the presence of SAS (from 1.67 ± 0.67 to 2.01 ± 0.78 nM). In contrast, electrical vagal nerve stimulation increased myocardial interstitial ACh level to the same degree regardless of SAS (from 1.66 ± 0.16 to 3.93 ± 0.72 nM without SAS vs. 4.05 ± 0.89 nM with SAS). CONCLUSION Sympathetic afferent stimulation inhibited medetomidine-induced ACh release, but not electrical stimulation-induced ACh release, suggesting that SAS inhibited medetomidine-induced vagal activation via central mechanisms. While central vagal activation by α2 -adrenergic agonists could be an alternative to electrical vagal activation, blocking sympathetic afferent input may be important to increase the efficacy of α2 -adrenergic agonists in enhancing vagal nerve activity.
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Affiliation(s)
- T. Kawada
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - T. Akiyama
- Department of Cardiac Physiology; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - S. Shimizu
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - A. Kamiya
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - K. Uemura
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - M. J. Turner
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - M. Shirai
- Department of Cardiac Physiology; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - M. Sugimachi
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
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Folkesson M, Mackey AL, Langberg H, Oskarsson E, Piehl-Aulin K, Henriksson J, Kadi F. The expression of heat shock protein in human skeletal muscle: effects of muscle fibre phenotype and training background. Acta Physiol (Oxf) 2013; 209:26-33. [PMID: 23710799 DOI: 10.1111/apha.12124] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 06/03/2012] [Accepted: 05/23/2013] [Indexed: 11/28/2022]
Abstract
AIM Exercise-induced adaptations of skeletal muscle are related to training mode and can be muscle fibre type specific. This study aimed to investigate heat shock protein expression in type I and type II muscle fibres in resting skeletal muscle of subjects with different training backgrounds. METHODS Three groups of subjects were included: healthy active not engaged in any training programme (ACT, n = 12), resistance trained (RES, n = 6) and endurance trained (END, n = 8). Biopsies were obtained from vastus lateralis, and immunohistochemistry was performed using monoclonal antibodies against myosin heavy chain I and IIA, αB-crystallin, HSP27, HSP60 and HSP70. RESULTS In ACT and RES, but not in END, a fibre type-specific expression with higher staining intensity in type I than type II fibres was seen for αB-crystallin. The opposite (II > I) was found for HSP27 in subjects from ACT (6 of 12 subjects) and RES (3 of 6), whereas all subjects from END displayed uniform staining. HSP60 showed no fibre-specific expression. HSP70 displayed a fibre-specific expression pattern (I > II) in ACT (4 of 12), but not in END or RES. CONCLUSION This study shows that the level of expression of the different HSPs in human skeletal muscle is influenced by muscle fibre phenotype. The fibre type-specific expression of HSP70 is influenced by resistance and endurance training, whereas those of αB-crystallin and HSP27 is influenced only by endurance training, suggesting the existence of a training-modality-specific action on the adaptive processes including heat shock proteins in human skeletal muscle.
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Affiliation(s)
- M. Folkesson
- School of Health and Medical Sciences; Örebro University; Örebro; Sweden
| | - A. L. Mackey
- Department of Orthopaedic Surgery M; Faculty of Health Sciences; Institute of Sports Medicine; Bispebjerg Hospital, and Centre for Healthy Ageing; University of Copenhagen; Copenhagen; Denmark
| | - H. Langberg
- Department of Orthopaedic Surgery M; Faculty of Health Sciences; Institute of Sports Medicine; Bispebjerg Hospital, and Centre for Healthy Ageing; University of Copenhagen; Copenhagen; Denmark
| | - E. Oskarsson
- School of Health and Medical Sciences; Örebro University; Örebro; Sweden
| | | | - J. Henriksson
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm; Sweden
| | - F. Kadi
- School of Health and Medical Sciences; Örebro University; Örebro; Sweden
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Cui BP, Li P, Sun HJ, Ding L, Zhou YB, Wang JJ, Kang YM, Zhu GQ. Ionotropic glutamate receptors in paraventricular nucleus mediate adipose afferent reflex and regulate sympathetic outflow in rats. Acta Physiol (Oxf) 2013; 209:45-54. [PMID: 23782804 DOI: 10.1111/apha.12125] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 04/15/2013] [Accepted: 05/28/2013] [Indexed: 12/27/2022]
Abstract
AIM Chemical stimulation of white adipose tissue (WAT) induces adipose afferent reflex (AAR) and results in increases in renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP). The enhanced AAR contributes to sympathetic activation and hypertension in obesity rats. This study was designed to investigate whether N-methyl-D-aspartate receptors (NMDAR) and non-NMDAR in paraventricular nucleus (PVN) modulate AAR and sympathetic outflow. METHODS Renal sympathetic nerve activity and MAP were recorded in anesthetized rats. AAR was evaluated by the RSNA and MAP responses to the injection of capsaicin into the four sites of right inguinal WAT (8.0 nmol for each site). RESULTS Bilateral PVN microinjection of NMDAR antagonist AP5 or MK-801, or non-NMDAR antagonist CNQX attenuated AAR, RSNA and MAP. AP5 + CNQX caused greater effects than AP5 or CNQX alone and almost abolished AAR. NMDAR agonist NMDA or non-NMDAR agonist AMPA enhanced the AAR, and increased RSNA and MAP, which were prevented by AP5 or CNQX pre-treatment respectively. Casein kinase 2 inhibitor DRB, NR2A antagonist NVP-AAM077 or NR2B antagonist CP-101,606 attenuated AAR, RSNA and MAP. NVP-AAM077 + CP-101,606 caused greater effects than NVP-AAM077 or CP-101,606 alone. Bilateral baroreceptor denervation and vagotomy enhanced AAR, which was abolished by PVN pre-treatment with AP5 + CNQX. Furthermore, AP5 + CNQX abolished the AAR induced by leptin in iWAT. CONCLUSION Both NMDAR and non-NMDAR in the PVN mediate AAR and contribute to the tonic control of sympathetic outflow and blood pressure. CK2, NR2A and NR2B subunits of NMDAR in the PVN are involved in the NMDAR-mediated tonic control of AAR, RSNA and MAP.
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Affiliation(s)
- B.-P. Cui
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing; Jiangsu; China
| | - P. Li
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing; Jiangsu; China
| | - H.-J. Sun
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing; Jiangsu; China
| | - L. Ding
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing; Jiangsu; China
| | - Y.-B. Zhou
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing; Jiangsu; China
| | - J.-J. Wang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing; Jiangsu; China
| | - Y.-M. Kang
- Department of Physiology and Pathophysiology; Cardiovascular Research Center; Xi'an Jiaotong University School of Medicine; Xi'an; China
| | - G.-Q. Zhu
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing; Jiangsu; China
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Iozzi D, Schubert R, Kalenchuk VU, Neri A, Sgaragli G, Fusi F, Saponara S. Quercetin relaxes rat tail main artery partly via a PKG-mediated stimulation of KCa 1.1 channels. Acta Physiol (Oxf) 2013; 208:329-39. [PMID: 23432816 DOI: 10.1111/apha.12083] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 01/05/2013] [Accepted: 02/08/2013] [Indexed: 01/08/2023]
Abstract
AIM Protein kinases, activated by vasodilator substances, affect vascular function by regulating large conductance Ca(2+) -activated K(+) (KCa 1.1) channels. Thus, the aim of the present investigation was to address the hypothesis that quercetin-induced vasorelaxation is caused by a PKG-mediated stimulation of KCa 1.1 currents. METHODS Single freshly isolated myocytes and endothelium-denuded rings of the rat tail main artery were employed for electrophysiological and contractility measurements respectively. RESULTS Quercetin relaxed vessels and increased KCa 1.1 currents in a concentration-dependent manner: both effects were antagonized by the specific KCa 1.1 channel blocker iberiotoxin. Stimulation of KCa 1.1 currents was fully reversible upon drug washout, markedly reduced by Rp-8-Br-PET-cGMPs, a PKG-inhibitor, but not affected by catalase. Quercetin shifted by 34.3 mV the voltage dependence of KCa 1.1 channel activation towards more negative membrane potentials without affecting its slope. Under conditions of tight functional coupling between sarcoplasmic reticulum Ca(2+) release sites and KCa 1.1 channels, quercetin decreased both the frequency and the amplitude of KCa 1.1 transient currents in a ryanodine-like manner. CONCLUSION The natural flavonoid quercetin relaxes the rat tail main artery partly via a PKG-mediated stimulation of smooth muscle KC a 1.1 channels.
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Affiliation(s)
- D. Iozzi
- Dipartimento di Scienze della Vita; Università degli Studi di Siena; Siena; Italy
| | - R. Schubert
- Research Division Cardiovascular Physiology; Centre for Biomedicine and Medical Technology Mannheim (CBTM), Medical Faculty Mannheim; University Heidelberg; Mannheim; Germany
| | | | - A. Neri
- Dipartimento di Scienze della Vita; Università degli Studi di Siena; Siena; Italy
| | - G. Sgaragli
- Dipartimento di Scienze della Vita; Università degli Studi di Siena; Siena; Italy
| | - F. Fusi
- Dipartimento di Scienze della Vita; Università degli Studi di Siena; Siena; Italy
| | - S. Saponara
- Dipartimento di Scienze della Vita; Università degli Studi di Siena; Siena; Italy
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Manko BO, Manko VV. Mechanisms of respiration intensification of rat pancreatic acini upon carbachol-induced Ca(2+) release. Acta Physiol (Oxf) 2013; 208:387-99. [PMID: 23692873 DOI: 10.1111/apha.12119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 11/28/2012] [Accepted: 05/16/2013] [Indexed: 11/27/2022]
Abstract
AIM Acetylcholine as one of the main secretagogues modulates mitochondrial functions in acinar pancreacytes, presumably due to increase in ATP hydrolysis or Ca(2+) transport into mitochondria. The aim of this work was to investigate the mechanisms of carbachol (CCh) action on respiration and oxidative phosphorylation of isolated pancreatic acini. METHODS Respiration of intact or permeabilized rat pancreatic acini was studied at 37 °C using a Clark oxygen electrode. RESULTS Respiration rate of isolated acini in rest was 0.27 ± 0.01 nmol O2 s(-1) 10(-6) cells. Addition of 10 μM CCh into respiration chamber evoked biphasic stimulation of respiration. Rapid increase of respiration by 20.1% lasted for approx. 1 min, followed by decrease to level by 11.5% higher than control. Addition of 1 μm CCh caused monophasic increase by 11.5%. Preincubation (5 min) with 1 or 10 μm CCh elevated respiration rate by 12.5 or 11.2% respectively. FCCP prevented the effect of CCh. Preincubation with 1 (but not 10) μm CCh increased FCCP-uncoupled respiration rate. Thapsigargin slightly elevated respiration, but ryanodine did not. Application of 2-aminoethoxydiphenyl borate or ruthenium red prevented the effects of CCh on respiration, while oligomycin abolished them. Preincubation with 1 μm CCh prior to cell permeabilization increased respiration rate at pyruvate+malate oxidation, but not at succinate oxidation. In contrast, preincubation with 10 μm CCh decreased pyruvate+malate oxidation. CONCLUSION Medium CCh dose (1 μm) intensifies respiration and oxidative phosphorylation of acinar pancreacytes by feedforward mechanism via Ca(2+) transport into mitochondria and activation of Ca(2+) /ADP-sensitive mitochondrial dehydrogenases. Prolonged action of high CCh dose (10 μm) might impair mitochondrial functions.
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Affiliation(s)
- B. O. Manko
- Biology faculty; Department of Human and Animal Physiology Hrushevsky; Ivan Franko National university of Lviv; Lviv; Ukraine
| | - V. V. Manko
- Biology faculty; Department of Human and Animal Physiology Hrushevsky; Ivan Franko National university of Lviv; Lviv; Ukraine
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Lempiäinen J, Finckenberg P, Mervaala EE, Sankari S, Levijoki J, Mervaala EM. Caloric restriction ameliorates kidney ischaemia/reperfusion injury through PGC-1α-eNOS pathway and enhanced autophagy. Acta Physiol (Oxf) 2013; 208:410-21. [PMID: 23710679 DOI: 10.1111/apha.12120] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 05/19/2013] [Indexed: 12/14/2022]
Abstract
AIM We investigated whether preconditioning with caloric restriction (CR) ameliorates kidney ischaemia/reperfusion (I/R) injury and whether the salutary effects of CR are mediated through enhanced autophagy and/or activation of key metabolic sensors SIRT1, AMP-kinase and PGC-1α. METHODS Six- to seven-week-old Wistar rats were divided into three groups: (i) sham-operated group; (ii) I/R group (40-min ischaemia followed by 24 h of reperfusion); and (iii) I/R group kept under CR (energy intake 70%) for 2 weeks before surgery. In additional experiments, sirtinol and 3-methyladenine (3-MA) were used as inhibitors of SIRT1 and autophagy respectively. Renal function was measured, and acute tubular damage and nitrotyrosine expression were scored. Kidney adenosine monophosphate-activated kinase (AMPK), SIRT1, eNOS, PGC-1α and LC-3B expressions were measured. RESULTS Caloric restriction improved renal function, protected against the development of acute tubular necrosis and attenuated I/R-induced nitrosative stress. Kidney I/R injury decreased eNOS and PGC-1α expression, inhibit autophagy and increased SIRT1 and AMPK expressions by 2.6- and fourfold respectively. However, phosphorylation level of AMPK was decreased. As compared with I/R injury group, CR further increased kidney SIRT1 expression by 1.8-fold, promoted autophagy and counteracted I/R-induced decreases in the expression of eNOS and PGC-1α. 3-MA abolished the renoprotective effects of CR, whereas sirtinol did not influence renal function in CR rats with I/R injury. CONCLUSIONS Caloric restriction ameliorates acute kidney I/R injury through enhanced autophagy and counteraction of I/R-induced decreases in the renal expression of eNOS and PGC-1α.
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Affiliation(s)
- J. Lempiäinen
- Institute of Biomedicine, Pharmacology; University of Helsinki; Helsinki; Finland
| | - P. Finckenberg
- Institute of Biomedicine, Pharmacology; University of Helsinki; Helsinki; Finland
| | - E. E. Mervaala
- Institute of Biomedicine, Pharmacology; University of Helsinki; Helsinki; Finland
| | - S. Sankari
- Department of Production Animal Medicine; University of Helsinki; Helsinki; Finland
| | | | - E. M. Mervaala
- Institute of Biomedicine, Pharmacology; University of Helsinki; Helsinki; Finland
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Schroll S, Lange TJ, Arzt M, Sebah D, Nowrotek A, Lehmann H, Wensel R, Pfeifer M, Blumberg FC. Effects of simvastatin on pulmonary fibrosis, pulmonary hypertension and exercise capacity in bleomycin-treated rats. Acta Physiol (Oxf) 2013; 208:191-201. [PMID: 23527830 DOI: 10.1111/apha.12085] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 07/09/2012] [Accepted: 02/07/2013] [Indexed: 11/29/2022]
Abstract
AIM Pulmonary fibrosis is often complicated by pulmonary hypertension. Statins reduce fibroblast activity in vitro and pulmonary hypertension in vivo. We investigated whether Simvastatin exerts beneficial effects on pulmonary fibrosis and pulmonary hypertension in Bleomycin-treated rats in vivo. METHODS Rats were randomly assigned to controls, Bleomycin, Bleomycin plus Simvastatin from day 1 to 28 and Bleomycin plus Simvastatin from day 13 to 28. 28 days after Bleomycin instillation, right ventricular systolic pressure (RVSP), right ventricular mass (RV/(LV+S)), right ventricular and circulating brain natriuretic peptide (BNP) levels were determined to assess pulmonary hypertension. Pulmonary hydroxyproline content (HPC), pulmonary connective tissue growth factor (CTGF) transcription and lung compliance (LC) were analysed to characterize pulmonary fibrosis. Exercise capacity was determined by treadmill tests. RESULTS Compared with controls, Bleomycin increased RVSP, RV/(LV+S), BNP levels, HPC and CTGF transcription and decreased LC significantly. Simvastatin administered from day 1 to 28 normalized all these parameters. Simvastatin administered from day 13 to 28 had no effect on HPC and LC, but reduced RV/(LV+S) significantly and induced a strong trend to lower RVSP and BNP levels. Exercise capacity was reduced by Bleomycin. Simvastatin significantly improved exercise intolerance in both treatment groups. CONCLUSIONS Simvastatin prevents the development of pulmonary fibrosis, but fails to attenuate already established pulmonary fibrosis. In contrast, it ameliorates pulmonary hypertension and thereby exercise capacity in the prevention and the treatment group regardless of its effects on pulmonary fibrosis. Whether statins are a treatment option in humans with pulmonary fibrosis needs to be investigated by further study.
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Affiliation(s)
- S. Schroll
- Department of Internal Medicine II; Pneumology; University of Regensburg; Regensburg; Germany
| | - T. J. Lange
- Department of Internal Medicine II; Pneumology; University of Regensburg; Regensburg; Germany
| | - M. Arzt
- Department of Internal Medicine II; Pneumology; University of Regensburg; Regensburg; Germany
| | - D. Sebah
- Department of Internal Medicine II; Pneumology; University of Regensburg; Regensburg; Germany
| | - A. Nowrotek
- Department of Internal Medicine II; Pneumology; University of Regensburg; Regensburg; Germany
| | - H. Lehmann
- Department of Internal Medicine II; Pneumology; University of Regensburg; Regensburg; Germany
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Marques Neto SR, Silva ADH, Santos MCPD, Ferraz EF, Nascimento JHM. The blockade of angiotensin AT1 and aldosterone receptors protects rats from synthetic androgen-induced cardiac autonomic dysfunction. Acta Physiol (Oxf) 2013; 208:166-71. [PMID: 23279762 DOI: 10.1111/apha.12056] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 10/15/2012] [Accepted: 12/15/2012] [Indexed: 11/29/2022]
Abstract
AIM This study aimed to evaluate the combined effects of exercise and antagonists of the angiotensin II and aldosterone receptors on cardiac autonomic regulation and ventricular repolarization in rats chronically treated with nandrolone decanoate (ND), a synthetic androgen. METHODS Thirty male Wistar rats were divided into six groups: sedentary, trained, ND-treated, trained and ND-treated, trained and treated with both ND and spironolactone, and trained and treated with both ND and losartan. ND (10 mg kg(-1) weekly) and the antagonists (20 mg kg(-1) daily) of the angiotensin II AT1 (losartan) and aldosterone (spironolactone) receptors were administered for 8 weeks. Exercise training was performed using a treadmill five times each week for 8 weeks. Following this 8-week training and treatment period, electrocardiogram recordings were obtained to determine the time and frequency domains of heart rate variability (HRV) and corrected QT interval (QTc). RESULTS Nandrolone decanoate treatment increased the QTc interval and reduced the parasympathetic indexes of HRV (RMSSD, pNN5 and high-frequency power) in sedentary and trained rats. The ratio between low- and high-frequency power (LF/HF) was higher in ND-treated groups. Both losartan and spironolactone treatments prevented the effects of ND on the QTc interval and the HRV parameters (RMSSD, pNN5, high-frequency power, and the LF/HF ratio). CONCLUSION Our results show that chronic treatment with a high dose of ND induces cardiac parasympathetic dysfunction and disturbances in ventricular repolarization in both sedentary and exercised rats. Furthermore, inhibiting the renin-angiotensin-aldosterone system using losartan, or spironolactone, prevented these deleterious effects.
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Affiliation(s)
| | - A. da H. Silva
- Instituto de Biofisica Carlos Chagas Filho; Universidade Federal do Rio de Janeiro; Rio de Janeiro; Brazil
| | - M. C. P. dos Santos
- Instituto de Biofisica Carlos Chagas Filho; Universidade Federal do Rio de Janeiro; Rio de Janeiro; Brazil
| | - E. F. Ferraz
- Instituto de Biofisica Carlos Chagas Filho; Universidade Federal do Rio de Janeiro; Rio de Janeiro; Brazil
| | - J. H. M. Nascimento
- Instituto de Biofisica Carlos Chagas Filho; Universidade Federal do Rio de Janeiro; Rio de Janeiro; Brazil
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Caronni A, Bolzoni F, Esposti R, Bruttini C, Cavallari P. Accuracy of pointing movements relies upon a specific tuning between anticipatory postural adjustments and prime mover activation. Acta Physiol (Oxf) 2013; 208:111-24. [PMID: 23398738 DOI: 10.1111/apha.12081] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 01/31/2013] [Accepted: 02/07/2013] [Indexed: 11/26/2022]
Abstract
AIM Equilibrium-perturbing forces associated with a voluntary upper-limb movement can be strong enough to displace the whole-body centre of mass. In this condition, anticipatory postural adjustments (APAs), developing in muscles other than the prime mover, are essential in maintaining the whole-body balance. Here, we test the hypothesis that APAs preceding an upper-limb target-reaching movement could play a role also in controlling the movement accuracy. METHODS Standing subjects (10) were asked to flex the right shoulder and touch with the index fingertip the centre of a target positioned in front of them. The reaching task was also performed while wearing and after doffing prismatic lenses (shifting the eye field rightward). EMGs from different upper- and lower-limb muscles and the mechanical actions to the ground were recorded. RESULTS (i) Before wearing prisms, subjects were very accurate in hitting the target, and the pointing movements were accompanied by APAs in quadriceps (Q) and tibialis anterior (TA) of both sides, and in right hamstrings (H) and soleus (SOL). (ii) After donning prisms, rightward pointing errors occurred, associated with a significant APA increase in right Q and TA, but without changes in the recruitment of right anterior deltoid (prime mover) and biceps brachii. (iii) These pointing errors were progressively compensated in about 10 trials, indicating a sensorimotor adaptation, and APAs returned to values recorded before wearing prisms. (iv) After doffing prisms, pointing errors occurred in the opposite direction but changes in APAs did not reach significance. CONCLUSION We propose that, besides preserving the whole-body balance, APAs are also tailored to obtain an accurate voluntary movement.
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Affiliation(s)
- A. Caronni
- Human Physiology Section of the DePT; Università degli Studi di Milano; Milan; Italy
| | - F. Bolzoni
- Human Physiology Section of the DePT; Università degli Studi di Milano; Milan; Italy
| | - R. Esposti
- Human Physiology Section of the DePT; Università degli Studi di Milano; Milan; Italy
| | - C. Bruttini
- Human Physiology Section of the DePT; Università degli Studi di Milano; Milan; Italy
| | - P. Cavallari
- Human Physiology Section of the DePT; Università degli Studi di Milano; Milan; Italy
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Silva LA, Tromm CB, Da Rosa G, Bom K, Luciano TF, Tuon T, De Souza CT, Pinho RA. Creatine supplementation does not decrease oxidative stress and inflammation in skeletal muscle after eccentric exercise. J Sports Sci 2013; 31:1164-76. [PMID: 23560674 DOI: 10.1080/02640414.2013.773403] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Thirty-six male rats were used; divided into 6 groups (n = 6): saline; creatine (Cr); eccentric exercise (EE) plus saline 24 h (saline + 24 h); eccentric exercise plus Cr 24 h (Cr + 24 h); eccentric exercise plus saline 48 h (saline + 48 h); and eccentric exercise plus Cr 48 h (Cr + 48 h). Cr supplementation was administered as a solution of 300 mg · kg body weight(-1) · day(-1) in 1 mL water, for two weeks, before the eccentric exercise. The animals were submitted to one downhill run session at 1.0 km · h(-1) until exhaustion. Twenty-four and forty-eight hours after the exercise, the animals were killed, and the quadriceps were removed. Creatine kinase levels, superoxide production, thiobarbituric acid reactive substances (TBARS) level, carbonyl content, total thiol content, superoxide dismutase, catalase, glutathione peroxidase, interleukin-1b (IL-1β), nuclear factor kappa B (NF-kb), and tumour necrosis factor (TNF) were analysed. Cr supplementation neither decreases Cr kinase, superoxide production, lipoperoxidation, carbonylation, total thiol, IL-1β, NF-kb, or TNF nor alters the enzyme activity of superoxide dismutase, catalase, and glutathione peroxides in relation to the saline group, respectively (P < 0.05). There are positive correlations between Cr kinase and TBARS and TNF-α 48 hours after eccentric exercise. The present study suggests that Cr supplementation does not decrease oxidative stress and inflammation after eccentric contraction.
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Affiliation(s)
- Luciano A Silva
- Exercise Biochemistry and Physiology Laboratory, Postgraduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, 88806‑000, Criciúma, SC, Brazil.
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Carlström M, Brown RD, Yang T, Hezel M, Larsson E, Scheffer PG, Teerlink T, Lundberg JO, Persson AEG. L-arginine or tempol supplementation improves renal and cardiovascular function in rats with reduced renal mass and chronic high salt intake. Acta Physiol (Oxf) 2013; 207:732-41. [PMID: 23387940 DOI: 10.1111/apha.12079] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Revised: 01/31/2013] [Accepted: 02/03/2013] [Indexed: 12/23/2022]
Abstract
AIM Early life reduction in nephron number and chronic high salt intake cause development of renal and cardiovascular disease, which has been associated with oxidative stress and nitric oxide (NO) deficiency. We investigated the hypothesis that interventions stimulating NO signalling or reducing oxidative stress may restore renal autoregulation, attenuate hypertension and reduce renal and cardiovascular injuries following reduction in renal mass and chronic high salt intake. METHODS Male Sprague-Dawley rats were uninephrectomized (UNX) or sham-operated at 3 weeks of age and given either a normal-salt (NS) or high-salt (HS) diet. Effects on renal and cardiovascular functions were assessed in rats supplemented with substrate for NO synthase (L-Arg) or a superoxide dismutase mimetic (Tempol). RESULTS Rats with UNX + HS developed hypertension and displayed increased renal NADPH oxidase activity, elevated levels of oxidative stress markers in plasma and urine, and reduced cGMP in plasma. Histological analysis showed signs of cardiac and renal inflammation and fibrosis. These changes were linked with abnormal renal autoregulation, measured as a stronger tubuloglomerular feedback (TGF) response. Simultaneous treatment with L-Arg or Tempol restored cGMP levels in plasma and increased markers of NO signalling in the kidney. This was associated with normalized TGF responses, attenuated hypertension and reduced signs of histopathological changes in the kidney and in the heart. CONCLUSION Reduction in nephron number during early life followed by chronic HS intake is associated with oxidative stress, impaired renal autoregulation and development of hypertension. Treatment strategies that increase NO bioavailability, or reduce levels of reactive oxygen species, were proven beneficial in this model of renal and cardiovascular disease.
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Affiliation(s)
| | | | - T. Yang
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm; Sweden
| | - M. Hezel
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm; Sweden
| | - E. Larsson
- Department of Genetics and Pathology; Uppsala University; Uppsala; Sweden
| | - P. G. Scheffer
- Department of Clinical Chemistry; VU University Medical Centre; Amsterdam; the Netherlands
| | - T. Teerlink
- Department of Clinical Chemistry; VU University Medical Centre; Amsterdam; the Netherlands
| | - J. O. Lundberg
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm; Sweden
| | - A. E. G. Persson
- Department of Medical Cell Biology; Uppsala University; Uppsala; Sweden
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Björling K, Morita H, Olsen MF, Prodan A, Hansen PB, Lory P, Holstein-Rathlou NH, Jensen LJ. Myogenic tone is impaired at low arterial pressure in mice deficient in the low-voltage-activated CaV 3.1 T-type Ca(2+) channel. Acta Physiol (Oxf) 2013; 207:709-20. [PMID: 23356724 DOI: 10.1111/apha.12066] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 12/27/2012] [Accepted: 01/17/2013] [Indexed: 11/28/2022]
Abstract
AIM Using mice deficient in the CaV 3.1 T-type Ca(2+) channel, the aim of the present study was to elucidate the molecular identity of non-L-type channels involved in vascular tone regulation in mesenteric arteries and arterioles. METHODS We used immunofluorescence microscopy to localize CaV 3.1 channels, patch clamp electrophysiology to test the effects of a putative T-type channel blocker NNC 55-0396 on whole-cell Ca(2+) currents, pressure myography and Ca(2+) imaging to test diameter and Ca(2+) responses of the applied vasoconstrictors, and Q-PCR to check mRNA expression levels of several Ca(2+) handling proteins in wild-type and CaV 3.1(-/-) mice. RESULTS Our data indicated that CaV 3.1 channels are important for the maintenance of myogenic tone at low pressures (40-80 mm Hg), whereas they are not involved in high-voltage-activated Ca(2+) currents, Ca(2+) entry or vasoconstriction to high KCl in mesenteric arteries and arterioles. Furthermore, we show that NNC 55-0396 is not a specific T-type channel inhibitor, as it potently blocks L-type and non-L-type high-voltage-activated Ca(2+) currents in mouse mesenteric vascular smooth muscle cell. CONCLUSION Our data using mice deficient in the CaV 3.1 T-type channel represent new evidence for the involvement of non-L-type channels in arteriolar tone regulation. We showed that CaV 3.1 channels are important for the myogenic tone at low arterial pressure, which is potentially relevant under resting conditions in vivo. Moreover, CaV 3.1 channels are not involved in Ca(2+) entry and vasoconstriction to large depolarization with, for example, high KCl. Finally, we caution against using NNC 55-0396 as a specific T-type channel blocker in native cells expressing high-voltage-activated Ca(2+) channels.
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Affiliation(s)
- K. Björling
- Department of Veterinary Clinical and Animal Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Denmark
| | - H. Morita
- Special Patient Oral Care Unit; Kyushu University Hospital; Fukuoka; Japan
| | - M. F. Olsen
- Department of Veterinary Clinical and Animal Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Denmark
| | - A. Prodan
- Department of Veterinary Clinical and Animal Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Denmark
| | - P. B. Hansen
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense; Denmark
| | - P. Lory
- CNRS; Institut de Génomique Fonctionnelle; Université de Montpellier; France
| | - N.-H. Holstein-Rathlou
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Denmark
| | - L. J. Jensen
- Department of Veterinary Clinical and Animal Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Denmark
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Dietrich A, Mathia S, Kaminski H, Mutig K, Rosenberger C, Mrowka R, Bachmann S, Paliege A. Chronic activation of vasopressin V2 receptor signalling lowers renal medullary oxygen levels in rats. Acta Physiol (Oxf) 2013; 207:721-31. [PMID: 23347696 DOI: 10.1111/apha.12067] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 12/27/2012] [Accepted: 01/17/2013] [Indexed: 12/17/2022]
Abstract
AIM In the present study, we aimed to elucidate the effects of chronic vasopressin administration on renal medullary oxygen levels. METHODS Adult Sprague Dawley or vasopressin-deficient Brattleboro rats were treated with the vasopressin V2 receptor agonist, desmopressin (5 ng/h; 3d), or its vehicle via osmotic minipumps. Immunostaining for pimonidazole and the transcription factor HIF-1α (hypoxia-inducible factor-1α) were used to identify hypoxic areas. Activation of HIF-target gene expression following desmopressin treatment was studied by microarray analysis. RESULTS Pimonidazole staining was detected in the outer and inner medulla of desmopressin-treated rats, whereas staining in control animals was weak or absent. HIF-1α immunostaining demonstrated nuclear accumulation in the papilla of desmopressin-treated animals, whereas no staining was observed in the controls. Gene expression analysis revealed significant enrichment of HIF-target genes in the group of desmopressin-regulated gene products (P = 2.6*10(-21) ). Regulated products included insulin-like growth factor binding proteins 1 and 3, angiopoietin 2, fibronectin, cathepsin D, hexokinase 2 and cyclooxygenase 2. CONCLUSION Our results demonstrate that an activation of the renal urine concentrating mechanism by desmopressin causes renal medullary hypoxia and an upregulation of hypoxia-inducible gene expression.
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Affiliation(s)
- A. Dietrich
- Department of Anatomy; Charité-Universitätsmedizin Berlin; Berlin; Germany
| | - S. Mathia
- Department of Nephrology; Charité-Universitätsmedizin Berlin; Berlin; Germany
| | - H. Kaminski
- Department of Anatomy; Charité-Universitätsmedizin Berlin; Berlin; Germany
| | - K. Mutig
- Department of Anatomy; Charité-Universitätsmedizin Berlin; Berlin; Germany
| | - C. Rosenberger
- Department of Nephrology; Charité-Universitätsmedizin Berlin; Berlin; Germany
| | - R. Mrowka
- Experimentelle Nephrologie; KIM III; Universitästsklinikum Jena; Jena; Germany
| | - S. Bachmann
- Department of Anatomy; Charité-Universitätsmedizin Berlin; Berlin; Germany
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Kawada T, Li M, Shimizu S, Kamiya A, Uemura K, Turner MJ, Mizuno M, Sugimachi M. High-frequency dominant depression of peripheral vagal control of heart rate in rats with chronic heart failure. Acta Physiol (Oxf) 2013; 207:494-502. [PMID: 23279751 DOI: 10.1111/apha.12055] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 12/02/2012] [Accepted: 12/15/2012] [Indexed: 12/13/2022]
Abstract
AIM To examine whether dynamic characteristics of the peripheral vagal control of heart rate (HR) are altered in chronic heart failure (CHF). METHODS The right vagal nerve was electrically stimulated according to a binary white noise signal, and the transfer function from vagal nerve stimulation (VNS) to HR was estimated in the frequency range from 0.01 to 1 Hz in five control rats and five CHF rats under anaesthetized conditions. The rate of VNS was changed among 10, 20 and 40 Hz. RESULTS A multiple linear regression analysis indicated that the increase in the VNS rate augmented the ratio of the high-frequency (HF) gain to the steady-state gain in the control group but not in the CHF group. As a result, the dynamic gain of the transfer function in the frequencies near 1 Hz decreased more in the CHF group than in the control group. CONCLUSION Changes in the dynamic characteristics of the peripheral vagal control of HR may contribute to the manifestation of decreased HF components of HR variability observed in CHF.
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Affiliation(s)
- T. Kawada
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - M. Li
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - S. Shimizu
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - A. Kamiya
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - K. Uemura
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - M. J. Turner
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
| | - M. Mizuno
- Department of Health Care Sciences; University of Texas Southwestern Medical Center; Dallas; TX; USA
| | - M. Sugimachi
- Department of Cardiovascular Dynamics; National Cerebral and Cardiovascular Center; Osaka; Japan
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