scholarly journals Antecedent hydrogen sulfide elicits an anti-inflammatory phenotype in postischemic murine small intestine: role of BK channels

2010 ◽  
Vol 299 (5) ◽  
pp. H1554-H1567 ◽  
Author(s):  
Mozow Y. Zuidema ◽  
Yan Yang ◽  
Meifang Wang ◽  
Theodore Kalogeris ◽  
Yajun Liu ◽  
...  
Keyword(s):  
Small Intestine ◽  
Hydrogen Sulfide ◽  
Ischemia Reperfusion ◽  
Bk Channels ◽  
Bk Channel ◽  
Confocal Imaging ◽  
Sodium Hydrosulfide ◽  
Inflammatory Phenotype ◽  
Anti Inflammatory

The objectives of this study were to determine the role of calcium-activated, small (SK), intermediate (IK), and large (BK) conductance potassium channels in initiating the development of an anti-inflammatory phenotype elicited by preconditioning with an exogenous hydrogen sulfide (H2S) donor, sodium hydrosulfide (NaHS). Intravital microscopy was used to visualize rolling and firmly adherent leukocytes in vessels of the small intestine of mice preconditioned with NaHS (in the absence and presence of SK, IK, and BK channel inhibitors, apamin, TRAM-34, and paxilline, respectively) or SK/IK (NS-309) or BK channel activators (NS-1619) 24 h before ischemia-reperfusion (I/R). I/R induced marked increases in leukocyte rolling and adhesion, effects that were largely abolished by preconditioning with NaHS, NS-309, or NS-1619. The postischemic anti-inflammatory effects of NaHS-induced preconditioning were mitigated by BKB channel inhibitor treatment coincident with NaHS, but not by apamin or TRAM-34, 24 h before I/R. Confocal imaging and immunohistochemistry were used to demonstrate the presence of BKα subunit staining in both endothelial and vascular smooth muscle cells of isolated, pressurized mesenteric venules. Using patch-clamp techniques, we found that BK channels in cultured endothelial cells were activated after exposure to NaHS. Bath application of the same concentration of NaHS used in preconditioning protocols led to a rapid increase in a whole cell K+ current; specifically, the component of K+ current blocked by the selective BK channel antagonist iberiotoxin. The activation of BK current by NaHS could also be demonstrated in single channel recording mode where it was independent of a change in intracellular Ca+ concentration. Our data are consistent with the concept that H2S induces the development of an anti-adhesive state in I/R in part mediated by a BK channel-dependent mechanism.

scholarly journals Antecedent hydrogen sulfide elicits an anti-inflammatory phenotype in postischemic murine small intestine: role of heme oxygenase-1

2011 ◽  
Vol 301 (3) ◽  
pp. H888-H894 ◽  
Author(s):  
Mozow Y. Zuidema ◽  
Kelly J. Peyton ◽  
William P. Fay ◽  
William Durante ◽  
Ronald J. Korthuis
Keyword(s):  
Small Intestine ◽  
Hydrogen Sulfide ◽  
Heme Oxygenase ◽  
Leukocyte Adhesion ◽  
Protoporphyrin Ix ◽  
Heme Oxygenase 1 ◽  
Inflammatory Phenotype ◽  
Murine Small Intestine ◽  
Anti Inflammatory

We recently demonstrated that preconditioning with an exogenous hydrogen sulfide donor (NaHS-PC) 24 h before ischemia and reperfusion (I/R) causes postcapillary venules to shift to an anti-inflammatory phenotype in C57BL/6J wild-type (WT) mice such that these vessels fail to support increases in postischemic leukocyte rolling (LR) and leukocyte adhesion (LA). The objective of the present study was to determine whether heme oxygenase-1 (HO-1) is a mediator of these anti-inflammatory effects noted during I/R in mice preconditioned with NaHS. Intravital fluorescence microscopy was used to visualize LR and LA in single postcapillary venules of the murine small intestine. I/R induced marked increases in LR and LA, effects that were prevented by NaHS-PC. Treatment with the HO inhibitor tin protoporphyrin IX, but not the inactive protoporphyrin CuPPIX, just before reperfusion prevented the anti-inflammatory effects of antecedent NaHS. The anti-inflammatory effects of NaHS-PC were mimicked by preconditioning with hemin, an agent that induces HO-1 expression. We then evaluated the effect of NaHS as a preconditioning stimulus in mice that were genetically deficient in HO-1 (HO-1−/−on an H129 background with appropriate WT strain controls). NaHS-PC was ineffective in HO-1−/−mice. Our work indicates that HO-1 serves as an effector of the anti-inflammatory effects of NaHS-PC during I/R 24 h later.

The Role of Reactive Oxygen Species, Kinases, Hydrogen Sulfide, and Nitric Oxide in the Regulation of Autophagy and Their Impact on Ischemia and Reperfusion Injury in the Heart

2020 ◽  
Vol 16 ◽  
Author(s):  
Andrey Krylatov ◽  
Leonid Maslov ◽  
Sergey Y. Tsibulnikov ◽  
Nikita Voronkov ◽  
Alla Boshchenko ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Reactive Oxygen Species ◽  
Hydrogen Sulfide ◽  
Ischemia Reperfusion ◽  
Reactive Oxygen ◽  
Ischemia And Reperfusion ◽  
Oxygen Species ◽  
Ischemia And Reperfusion Injury ◽  
Adaptive Process

: There is considerable evidence in the heart that autophagy in cardiomyocytes is activated by hypoxia/reoxygenation (H/R) or in hearts by ischemia/reperfusion (I/R). Depending upon the experimental model and duration of ischemia, increases in autophagy in this setting maybe beneficial (cardioprotective) or deleterious (exacerbate I/R injury). Aside from the conundrum as to whether or not autophagy is an adaptive process, it is clearly regulated by a number of diverse molecules including reactive oxygen species (ROS), various kinases, hydrogen sulfide (H2S) and nitric oxide (NO). The purpose this review is to address briefly the controversy regarding the role of autophagy in this setting and to examine a variety of disparate molecules that are involved in its regulation.

The Yin and Yang of BK Channels in Epilepsy

2018 ◽  
Vol 17 (4) ◽  
pp. 272-279 ◽  
Author(s):  
Yudan Zhu ◽  
Shuzhang Zhang ◽  
Yijun Feng ◽  
Qian Xiao ◽  
Jiwei Cheng ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Bk Channels ◽  
Bk Channel ◽  
Potential Shape ◽  
Yin And Yang ◽  
The Central Nervous System ◽  
Action Potential Shape ◽  
Excitability Of Neurons

Background & Objective: The large conductance calcium-activated potassium (BK) channel, extensively distributed in the central nervous system (CNS), is considered as a vital player in the pathogenesis of epilepsy, with evidence implicating derangement of K+ as well as regulating action potential shape and duration. However, unlike other channels implicated in epilepsy whose function in neurons could clearly be labeled “excitatory” or “inhibitory”, the unique physiological behavior of the BK channel allows it to both augment and decrease the excitability of neurons. Thus, the role of BK in epilepsy is controversial so far, and a growing area of intense investigation. Conclusion: Here, this review aims to highlight recent discoveries on the dichotomous role of BK channels in epilepsy, focusing on relevant BK-dependent pro- as well as antiepileptic pathways, and discuss the potential of BK specific modulators for the treatment of epilepsy.

Hydrogen sulfide-mediated cardioprotection: mechanisms and therapeutic potential

2010 ◽  
Vol 120 (6) ◽  
pp. 219-229 ◽  
Author(s):  
Madhav Lavu ◽  
Shashi Bhushan ◽  
David J. Lefer
Keyword(s):  
Blood Pressure ◽  
Cardiovascular Disease ◽  
Hydrogen Sulfide ◽  
Therapeutic Potential ◽  
Blood Pressure Regulation ◽  
Pressure Regulation ◽  
Signalling Molecule ◽  
Anti Inflammatory ◽  
Antioxidant Effects

H2S (hydrogen sulfide), viewed with dread for more than 300 years, is rapidly becoming a ubiquitously present and physiologically relevant signalling molecule. Knowledge of the production and metabolism of H2S has spurred interest in delineating its functions both in physiology and pathophysiology of disease. Although its role in blood pressure regulation and interaction with NO is controversial, H2S, through its anti-apoptotic, anti-inflammatory and antioxidant effects, has demonstrated significant cardioprotection. As a result, a number of sulfide-donor drugs, including garlic-derived polysulfides, are currently being designed and investigated for the treatment of cardiovascular conditions, specifically myocardial ischaemic disease. However, huge gaps remain in our knowledge about this gasotransmitter. Only by additional studies will we understand more about the role of this intriguing molecule in the treatment of cardiovascular disease.

scholarly journals Regulatory γ1 subunits defy symmetry in functional modulation of BK channels

2018 ◽  
Vol 115 (40) ◽  
pp. 9923-9928 ◽  
Author(s):  
Vivian Gonzalez-Perez ◽  
Manu Ben Johny ◽  
Xiao-Ming Xia ◽  
Christopher J. Lingle
Keyword(s):  
Single Channel ◽  
Regulatory Protein ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Bk Channels ◽  
Bk Channel ◽  
Single Type ◽  
Regulatory Subunits ◽  
And Function

Structural symmetry is a hallmark of homomeric ion channels. Nonobligatory regulatory proteins can also critically define the precise functional role of such channels. For instance, the pore-forming subunit of the large conductance voltage and calcium-activated potassium (BK, Slo1, or KCa1.1) channels encoded by a single KCa1.1 gene assembles in a fourfold symmetric fashion. Functional diversity arises from two families of regulatory subunits, β and γ, which help define the range of voltages over which BK channels in a given cell are activated, thereby defining physiological roles. A BK channel can contain zero to four β subunits per channel, with each β subunit incrementally influencing channel gating behavior, consistent with symmetry expectations. In contrast, a γ1 subunit (or single type of γ1 subunit complex) produces a functionally all-or-none effect, but the underlying stoichiometry of γ1 assembly and function remains unknown. Here we utilize two distinct and independent methods, a Forster resonance energy transfer-based optical approach and a functional reporter in single-channel recordings, to reveal that a BK channel can contain up to four γ1 subunits, but a single γ1 subunit suffices to induce the full gating shift. This requires that the asymmetric association of a single regulatory protein can act in a highly concerted fashion to allosterically influence conformational equilibria in an otherwise symmetric K+channel.

Abstract T P87: Hydrogen Sulfide Enhances Neurogenesis through the IRAK-1/GSK3β/AKT Signaling Pathways after Ischemic Stroke

Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Pradip K Kamat ◽  
Anuradha Kalani ◽  
Neetu Tyagi
Keyword(s):  
Hydrogen Sulfide ◽  
Signaling Pathways ◽  
Ventricular Zone ◽  
Ischemia Reperfusion ◽  
Analysis Data ◽  
Akt Signaling ◽  
Artery Occlusion ◽  
Cortical Region ◽  
Neuronal Function

Background and purpose: Increasing evidence signifying that inflammation has an ample role in the ischemia and; neurogenesis is somehow affected by inflammation. Current approved therapy for stroke is limited and new strategies need to be investigated. Hydrogen sulfide (H2S) showed neuro-protective however, role of H2S in stroke-induced neurogenesis is not known. Therefore, the present study was to determine the role of H2S in ischemia induced neurogenesis. Methods: To perform this study; we employed 8-10 weak old C57BL/6 mice with following groups: WT-Sham; WT+ ischemia reperfusion (IR) for 7 days; IR+GYY4137 (H2S donor, 30μM for 7 days; Intra peritoneal injection); and Sham+ GYY4137 (30μM for 7 day). Ischemia was created by the middle cerebral artery occlusion, (MCAO) for 50 min followed by reperfusion for 7 days. The brain tissue from different groups was used for biochemical, infarct area molecular and immunohistochemistry analysis. Data were analyzed by one way ANOVA followed by Tukey test. Results: We found increased protein expression of IRAK-1 (F=3, 27.01; P<.005), GSK3β 9 (F=3, 89.47; P<.005), p-AKT (F=3, 89.47; P<.005) and reduced expression of AKT p-AKT(F=3, 112.2; P<.005) in I/R group as compared to sham that indicates alteration of inflammatory signaling pathways. Further, we also found decreased level of Nestin (F=3, 35.32; P<.005), GFAP (F=3, 95.14; P<.001), NeuN (F=3, 123.4; P<.001), TUJ-1 (F=3, 112; P<.005), MAP-2 (F=3, 31.54; P<.0001), IL-6 (F=3, 55.7; p<.05) and BDNF (F=3, 166.5; P<.005) in cortical region of I/R group which indicates loss of neuronal function. Additionally, immunohistochemistry assay also revealed the loss of Nestin (P<.05), BDNF (P<.05), MAP-2 (P<.05) along with increased GSK-3β (P<.005) expression in sub ventricular zone (SVZ) and hippocampal region. Further, GYY4137 treatment for 7 days in ischemic group significantly restored the Nestin, GFAP, IL-6, NeuN, TUJ-1, MAP-2 and BDNF levels via regulating IRAK-1/GSK3β/AKT signaling pathways. Conclusion: Present study clearly demonstrate that H2S plays an important role in ischemia induced neurogenesis as well as protecting neuronal function through inhibition of IRAK1/GSK3β/AKT signaling pathways. Acknowledgement: This work was supported by NTHL107640-NT.

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