1
|
Sancho M, Klug NR, Harraz OF, Hill-Eubanks D, Nelson MT. Distinct potassium channel types in brain capillary pericytes. Biophys J 2024; 123:2110-2121. [PMID: 38444160 PMCID: PMC11309962 DOI: 10.1016/j.bpj.2024.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 01/25/2024] [Accepted: 03/01/2024] [Indexed: 03/07/2024] Open
Abstract
Capillaries, composed of electrically coupled endothelial cells and overlying pericytes, constitute the vast majority of blood vessels in the brain. The most arteriole-proximate three to four branches of the capillary bed are covered by α-actin-expressing, contractile pericytes. These mural cells have a distinctive morphology and express different markers compared with their smooth muscle cell (SMC) cousins but share similar excitation-coupling contraction machinery. Despite this similarity, pericytes are considerably more depolarized than SMCs at low intravascular pressures. We have recently shown that pericytes, such as SMCs, possess functional voltage-dependent Ca2+ channels and ATP-sensitive K+ channels. Here, we further investigate the complement of pericyte ion channels, focusing on members of the K+ channel superfamily. Using NG2-DsRed-transgenic mice and diverse configurations of the patch-clamp technique, we demonstrate that pericytes display robust inward-rectifier K+ currents that are primarily mediated by the Kir2 family, based on their unique biophysical characteristics and sensitivity to micromolar concentrations of Ba2+. Moreover, multiple lines of evidence, including characteristic kinetics, sensitivity to specific blockers, biophysical attributes, and distinctive single-channel properties, established the functional expression of two voltage-dependent K+ channels: KV1 and BKCa. Although these three types of channels are also present in SMCs, they exhibit distinctive current density and kinetics profiles in pericytes. Collectively, these findings underscore differences in the operation of shared molecular features between pericytes and SMCs and highlight the potential contribution of these three K+ ion channels in setting pericyte membrane potential, modulating capillary hemodynamics, and regulating cerebral blood flow.
Collapse
Affiliation(s)
- Maria Sancho
- Department of Pharmacology, University of Vermont, Burlington, Vermont; Department of Physiology, Faculty of Medicine, Complutense University of Madrid, Madrid, Spain.
| | - Nicholas R Klug
- Department of Pharmacology, University of Vermont, Burlington, Vermont
| | - Osama F Harraz
- Department of Pharmacology, University of Vermont, Burlington, Vermont; Vermont Center for Cardiovascular and Brain Health, Larner College of Medicine, University of Vermont, Burlington, Vermont
| | | | - Mark T Nelson
- Department of Pharmacology, University of Vermont, Burlington, Vermont; Vermont Center for Cardiovascular and Brain Health, Larner College of Medicine, University of Vermont, Burlington, Vermont; Division of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom.
| |
Collapse
|
2
|
Yuan Y, Arige V, Saito R, Mu Q, Brailoiu GC, Pereira GJS, Bolsover SR, Keller M, Bracher F, Grimm C, Brailoiu E, Marchant JS, Yule DI, Patel S. Two-pore channel-2 and inositol trisphosphate receptors coordinate Ca 2+ signals between lysosomes and the endoplasmic reticulum. Cell Rep 2024; 43:113628. [PMID: 38160394 PMCID: PMC10931537 DOI: 10.1016/j.celrep.2023.113628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 11/13/2023] [Accepted: 12/11/2023] [Indexed: 01/03/2024] Open
Abstract
Lysosomes and the endoplasmic reticulum (ER) are Ca2+ stores mobilized by the second messengers NAADP and IP3, respectively. Here, we establish Ca2+ signals between the two sources as fundamental building blocks that couple local release to global changes in Ca2+. Cell-wide Ca2+ signals evoked by activation of endogenous NAADP-sensitive channels on lysosomes comprise both local and global components and exhibit a major dependence on ER Ca2+ despite their lysosomal origin. Knockout of ER IP3 receptor channels delays these signals, whereas expression of lysosomal TPC2 channels accelerates them. High-resolution Ca2+ imaging reveals elementary events upon TPC2 opening and signals coupled to IP3 receptors. Biasing TPC2 activation to a Ca2+-permeable state sensitizes local Ca2+ signals to IP3. This increases the potency of a physiological agonist to evoke global Ca2+ signals and activate a downstream target. Our data provide a conceptual framework to understand how Ca2+ release from physically separated stores is coordinated.
Collapse
Affiliation(s)
- Yu Yuan
- Department of Cell and Developmental Biology, University College London, Gower Street, WC1E 6BT London, UK
| | - Vikas Arige
- Department of Pharmacology and Physiology, University of Rochester, 601 Elmwood Avenue, Rochester, NY 14642, USA
| | - Ryo Saito
- Department of Cell and Developmental Biology, University College London, Gower Street, WC1E 6BT London, UK; Department of Dermatology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8553, Japan
| | - Qianru Mu
- Department of Cell and Developmental Biology, University College London, Gower Street, WC1E 6BT London, UK
| | - Gabriela C Brailoiu
- Department of Pharmaceutical Sciences, Jefferson College of Pharmacy, Thomas Jefferson University, 901 Walnut Street, Philadelphia, PA 19107, USA
| | - Gustavo J S Pereira
- Department of Cell and Developmental Biology, University College London, Gower Street, WC1E 6BT London, UK; Department of Pharmacology, Federal University of São Paulo (UNIFESP), São Paulo 04044-020, Brazil
| | - Stephen R Bolsover
- Department of Cell and Developmental Biology, University College London, Gower Street, WC1E 6BT London, UK
| | - Marco Keller
- Department of Pharmacy-Center for Drug Research, Ludwig-Maximilian University, Butenandtstrasse 5-13, 81377 Munich, Germany
| | - Franz Bracher
- Department of Pharmacy-Center for Drug Research, Ludwig-Maximilian University, Butenandtstrasse 5-13, 81377 Munich, Germany
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilian University, Nussbaumstrasse 26, 80336 Munich, Germany; Immunology, Infection and Pandemic Research IIP, Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, 60596 Frankfurt, Germany
| | - Eugen Brailoiu
- Department of Neural Sciences and Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Jonathan S Marchant
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - David I Yule
- Department of Pharmacology and Physiology, University of Rochester, 601 Elmwood Avenue, Rochester, NY 14642, USA.
| | - Sandip Patel
- Department of Cell and Developmental Biology, University College London, Gower Street, WC1E 6BT London, UK.
| |
Collapse
|
3
|
Gu H, Shu Q, Dai M, Zou H, Wang Y, Cheng J, Su Y, Li F, Li B. Low concentration chlorantraniliprole-promoted Ca 2+ release drives a shift from autophagy to apoptosis in the silk gland of Bombyx mori. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 196:105585. [PMID: 37945221 DOI: 10.1016/j.pestbp.2023.105585] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 08/18/2023] [Accepted: 08/22/2023] [Indexed: 11/12/2023]
Abstract
The novel pesticide chlorantraniliprole (CAP) is widely used for pest control in agriculture, and the safety for non-target organisms of trace residues in the environment has received widespread attention. In the present study, exposure to low concentrations of CAP resulted in abnormal silk gland development in the B. mori, and induced the release of intracellular Ca2+ in addition to the triggering of Ca2+-dependent gene transcription. Moreover, the CAP treatment group exhibited down-regulation of oxidative phosphorylation and antioxidant enzyme-related genes in the silk gland, resulting in peroxide accumulation. Furthermore, transcript levels of autophagy-related genes were significantly up-regulated and protein levels of LC3-I and LC3-II were up-regulated, indicating an increase in autophagy. The protein levels of ATG5 and NtATG5 were also significantly up-regulated. While the protein levels of caspase3 and active caspase3 were significantly up-regulated consistent with the transcript levels of key genes in the apoptotic signaling pathway, ultimately affecting silk protein synthesis. Overall, these findings indicate that low concentration CAP induced abnormal development in the silk gland of B. mori by causing intracellular Ca2+ overload, which inhibits oxidative phosphorylation pathway and the removal of reactive oxygen species, leading to a driving a shift from autophagy to apoptosis. The findings herein provided a basis for evaluating the safety of CAP environmental residues on non-target organisms.
Collapse
Affiliation(s)
- Haoyi Gu
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, China
| | - Qilong Shu
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, China
| | - Minli Dai
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, China
| | - Hongbin Zou
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, China
| | - Yuanfei Wang
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, China
| | - Jialu Cheng
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, China
| | - Yue Su
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, China
| | - Fanchi Li
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, China; Sericulture Institute of Soochow University, Soochow University, Suzhou, China
| | - Bing Li
- School of Basic Medicine and Biological Sciences, Soochow University, Suzhou, China; Sericulture Institute of Soochow University, Soochow University, Suzhou, China.
| |
Collapse
|