1
|
Chen YJ, Chen C, Li MY, Li QQ, Zhang XJ, Huang R, Zhu XW, Bai CY, Zhang LY, Peng PH, Yang WM. Scutellarin Reduces Cerebral Ischemia Reperfusion Injury Involving in Vascular Endothelium Protection and PKG Signal. NATURAL PRODUCTS AND BIOPROSPECTING 2021; 11:659-670. [PMID: 34750765 PMCID: PMC8599605 DOI: 10.1007/s13659-021-00322-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 10/29/2021] [Indexed: 05/08/2023]
Abstract
Flavonoid glycoside scutellarin (SCU) has been widely applied in the treatment of cerebral ischemic diseases in China. In this article, we conducted research on the working mechanisms of SCU in hypoxia reoxygenation (HR) injury of isolated cerebral basilar artery (BA) and erebral ischemia reperfusion (CIR) injury in rat models. In isolated rat BA rings, HR causes endothelial dysfunction (ED) and acetylcholine (ACh) induces endothelium-dependent vasodilation. The myography result showed that SCU (100 µM) was able to significantly improve the endothelium-dependent vasodilation induced by Ach. However, SCU did not affect the ACh-induced relaxation in normal BA. Further studies suggested that SCU (10-1000 µM) dose-dependently induced relaxation in isolated BA rings which were significantly blocked by the cGMP dependent protein kinase (PKG) inhibitor Rp-8-Br-cGMPs (PKGI-rp, 4 µM). Pre-incubation with SCU (500 µM) reversed the impairment of endothelium-dependent vasodilation induced by HR, but the reversing effect was blocked if PKGI-rp (4 µM) was added. The brain slice staining test in rats' model of middle cerebral artery occlusion (MCAO) induced CIR proved that the administration of SCU (45, 90 mg/kg, iv) significantly reduced the area of cerebral infarction. The Western blot assay result showed that SCU (45 mg/kg, iv) increased brain PKG activity and PKG protein level after CIR surgery. In conclusion, our findings suggested that SCU possesses the ability of protecting brain cells against CIR injury through vascular endothelium protection and PKG signal.
Collapse
Affiliation(s)
- Ya-Juan Chen
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China
| | - Chen Chen
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China
| | - Meng-Yuan Li
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China
| | - Qing-Qing Li
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China
| | - Xiu-Juan Zhang
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China
| | - Rong Huang
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China
| | - Xing-Wei Zhu
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China
| | - Chun-Yun Bai
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China
| | - Liu-Yi Zhang
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China.
| | - Pei-Hua Peng
- Department of Anesthesiology, The First Affiliated Hospital of Kunming University, Kunming, 650032, China.
| | - Wei-Min Yang
- School of Pharmaceutical Science & Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, 1168 Western Chunrong Road, Yuhua Street, Chenggong New City, Kunming, 650500, China.
| |
Collapse
|
2
|
Shvetsova AA, Gaynullina DK, Tarasova OS, Schubert R. Remodeling of Arterial Tone Regulation in Postnatal Development: Focus on Smooth Muscle Cell Potassium Channels. Int J Mol Sci 2021; 22:ijms22115413. [PMID: 34063769 PMCID: PMC8196626 DOI: 10.3390/ijms22115413] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/15/2021] [Accepted: 05/18/2021] [Indexed: 11/30/2022] Open
Abstract
Maturation of the cardiovascular system is associated with crucial structural and functional remodeling. Thickening of the arterial wall, maturation of the sympathetic innervation, and switching of the mechanisms of arterial contraction from calcium-independent to calcium-dependent occur during postnatal development. All these processes promote an almost doubling of blood pressure from the moment of birth to reaching adulthood. This review focuses on the developmental alterations of potassium channels functioning as key smooth muscle membrane potential determinants and, consequently, vascular tone regulators. We present evidence that the pattern of potassium channel contribution to vascular control changes from Kir2, Kv1, Kv7 and TASK-1 channels to BKCa channels with maturation. The differences in the contribution of potassium channels to vasomotor tone at different stages of postnatal life should be considered in treatment strategies of cardiovascular diseases associated with potassium channel malfunction.
Collapse
Affiliation(s)
- Anastasia A. Shvetsova
- Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, 119234 Moscow, Russia; (D.K.G.); (O.S.T.)
- Correspondence:
| | - Dina K. Gaynullina
- Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, 119234 Moscow, Russia; (D.K.G.); (O.S.T.)
- Department of Physiology, Russian National Research Medical University, 117997 Moscow, Russia
| | - Olga S. Tarasova
- Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, 119234 Moscow, Russia; (D.K.G.); (O.S.T.)
- Laboratory of Exercise Physiology, State Research Center of the Russian Federation-Institute for Biomedical Problems, Russian Academy of Sciences, 123007 Moscow, Russia
| | - Rudolf Schubert
- Physiology, Institute of Theoretical Medicine, Medical Faculty, University of Augsburg, 86159 Augsburg, Germany;
| |
Collapse
|
3
|
Blum-Johnston C, Thorpe RB, Wee C, Opsahl R, Romero M, Murray S, Brunelle A, Blood Q, Wilson R, Blood AB, Zhang L, Longo LD, Pearce WJ, Wilson SM. Long-term hypoxia uncouples Ca 2+ and eNOS in bradykinin-mediated pulmonary arterial relaxation. Am J Physiol Regul Integr Comp Physiol 2018. [PMID: 29513562 DOI: 10.1152/ajpregu.00311.2017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bradykinin-induced activation of the pulmonary endothelium triggers a rise in intracellular Ca2+ that activates nitric oxide (NO)-dependent vasorelaxation. Chronic hypoxia is commonly associated with increased pulmonary vascular tone, which can cause pulmonary hypertension in responsive individuals. In the present study, we tested the hypothesis that long-term high-altitude hypoxia (LTH) diminishes bradykinin-induced Ca2+ signals and inhibits endothelial nitric oxide synthase (eNOS), prostacyclin (PGI2), and large-conductance K+ (BKCa) channels in sheep, which are moderately responsive to LTH, resulting in decreased pulmonary arterial vasorelaxation. Pulmonary arteries were isolated from ewes kept near sea level (720 m) or at high altitude (3,801 m) for >100 days. Vessel force was measured with wire myography and endothelial intracellular Ca2+ with confocal microscopy. eNOS was inhibited with 100 μM NG-nitro-l-arginine methyl ester (l-NAME), PGI2 production was inhibited with 10 µM indomethacin that inhibits cyclooxygenase, and BKCa channels were blocked with 1 mM tetraethylammonium. Bradykinin-induced endothelial Ca2+ signals increased following LTH, but bradykinin relaxation decreased. Furthermore, some vessels contracted in response to bradykinin after LTH. l-NAME sensitivity decreased, suggesting that eNOS dysfunction played a role in uncoupling Ca2+ signals and bradykinin relaxation. The Ca2+ ionophore A-23187 (10 µM) elicited an enhanced Ca2+ response following LTH while relaxation was unchanged although l-NAME sensitivity increased. Additionally, BKCa function decreased during bradykinin relaxation following LTH. Western analysis showed that BKCa α-subunit expression was increased by LTH while that for the β1 subunit was unchanged. Overall, these results suggest that those even moderately responsive to LTH can have impaired endothelial function.
Collapse
Affiliation(s)
- Carla Blum-Johnston
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California.,Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine , Loma Linda, California
| | - Richard B Thorpe
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Chelsea Wee
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Raechel Opsahl
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Monica Romero
- Advanced Imaging and Microscopy Core, Loma Linda University School of Medicine , Loma Linda, California
| | - Samuel Murray
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Alexander Brunelle
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Quintin Blood
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Rachael Wilson
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Arlin B Blood
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Lubo Zhang
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Lawrence D Longo
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - William J Pearce
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California
| | - Sean M Wilson
- Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine , Loma Linda, California.,Advanced Imaging and Microscopy Core, Loma Linda University School of Medicine , Loma Linda, California
| |
Collapse
|
4
|
Shamloo K, Chen J, Sardar J, Sherpa RT, Pala R, Atkinson KF, Pearce WJ, Zhang L, Nauli SM. Chronic Hypobaric Hypoxia Modulates Primary Cilia Differently in Adult and Fetal Ovine Kidneys. Front Physiol 2017; 8:677. [PMID: 28979210 PMCID: PMC5611369 DOI: 10.3389/fphys.2017.00677] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 08/24/2017] [Indexed: 11/13/2022] Open
Abstract
Hypoxic environments at high altitude have significant effects on kidney injury. Following injury, renal primary cilia display length alterations. Primary cilia are mechanosensory organelles that regulate tubular architecture. The effect of hypoxia on cilia length is still controversial in cultured cells, and no corresponding in vivo study exists. Using fetal and adult sheep, we here study the effect of chronic hypobaric hypoxia on the renal injury, intracellular calcium signaling and the relationship between cilia length and cilia function. Our results show that although long-term hypoxia induces renal fibrosis in both fetal and adult kidneys, fetal kidneys are more susceptible to hypoxia-induced renal injury. Unlike hypoxic adult kidneys, hypoxic fetal kidneys are characterized by interstitial edema, tubular disparition and atrophy. We also noted that there is an increase in the cilia length as well as an increase in the cilia function in the hypoxic fetal proximal and distal collecting epithelia. Hypoxia, however, has no significant effect on primary cilia in the adult kidneys. Increased cilia length is also associated with greater flow-induced intracellular calcium signaling in renal epithelial cells from hypoxic fetuses. Our studies suggest that while hypoxia causes renal fibrosis in both adult and fetal kidneys, hypoxia-induced alteration in cilia length and function are specific to more severe renal injuries in fetal hypoxic kidneys.
Collapse
Affiliation(s)
- Kiumars Shamloo
- Department of Biomedical and Pharmaceutical Sciences, Chapman UniversityIrvine, CA, United States
| | - Juan Chen
- Department of Biomedical and Pharmaceutical Sciences, Chapman UniversityIrvine, CA, United States
| | - Jasmine Sardar
- Department of Biomedical and Pharmaceutical Sciences, Chapman UniversityIrvine, CA, United States
| | - Rinzhin T Sherpa
- Department of Biomedical and Pharmaceutical Sciences, Chapman UniversityIrvine, CA, United States
| | - Rajasekharreddy Pala
- Department of Biomedical and Pharmaceutical Sciences, Chapman UniversityIrvine, CA, United States
| | - Kimberly F Atkinson
- Department of Biomedical and Pharmaceutical Sciences, Chapman UniversityIrvine, CA, United States
| | - William J Pearce
- Departments of Basic Sciences, Physiology and Pharmacology, Lawrence D. Longo MD Center for Perinatal Biology, Loma Linda University School of MedicineLoma Linda, CA, United States
| | - Lubo Zhang
- Departments of Basic Sciences, Physiology and Pharmacology, Lawrence D. Longo MD Center for Perinatal Biology, Loma Linda University School of MedicineLoma Linda, CA, United States
| | - Surya M Nauli
- Department of Biomedical and Pharmaceutical Sciences, Chapman UniversityIrvine, CA, United States.,Division of Nephrology and Hypertension, Department of Medicine, University of California, IrvineIrvine, CA, United States
| |
Collapse
|
5
|
Thorpe RB, Hubbell MC, Silpanisong J, Williams JM, Pearce WJ. Chronic hypoxia attenuates the vasodilator efficacy of protein kinase G in fetal and adult ovine cerebral arteries. Am J Physiol Heart Circ Physiol 2017; 313:H207-H219. [PMID: 28550175 DOI: 10.1152/ajpheart.00480.2016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 03/30/2017] [Accepted: 04/25/2017] [Indexed: 11/22/2022]
Abstract
Long-term hypoxia (LTH) attenuates nitric oxide-induced vasorelaxation in ovine middle cerebral arteries. Because cGMP-dependent protein kinase (PKG) is an important mediator of NO signaling in vascular smooth muscle, we tested the hypothesis that LTH diminishes the ability of PKG to interact with target proteins and cause vasorelaxation. Prominent among proteins that regulate vascular tone is the large-conductance Ca2+-sensitive K+ (BK) channel, which is a substrate for PKG and is responsive to phosphorylation on multiple serine/threonine residues. Given the influence of these proteins, we also examined whether LTH attenuates PKG and BK channel protein abundances and PKG activity. Middle cerebral arteries were harvested from normoxic and hypoxic (altitude of 3,820 m for 110 days) fetal and adult sheep. These arteries were denuded and equilibrated with 95% O2-5% CO2 in the presence of N-nitro-l-arginine methyl ester (l-NAME) to inhibit potential confounding influences of events upstream from PKG. Expression and activity of PKG-I were not significantly affected by chronic hypoxia in either fetal or adult arteries. Pretreatment with the BK inhibitor iberiotoxin attenuated vasorelaxation induced by 8-(4-chlorophenylthio)guanosine 3',5'-cyclic monophosphate in normoxic but not LTH arteries. The spatial proximities of PKG with BK channel α- and β1-proteins were examined using confocal microscopy, which revealed a strong dissociation of PKG with these proteins after LTH. These results support our hypothesis that hypoxia reduces the ability of PKG to attenuate vasoconstriction in part through suppression of the ability of PKG to associate with and thereby activate BK channels in arterial smooth muscle.NEW & NOTEWORTHY Using measurements of contractility, protein abundance, kinase activity, and confocal colocalization in fetal and adult ovine cerebral arteries, the present study demonstrates that long-term hypoxia diminishes the ability of cGMP-dependent protein kinase (PKG) to cause vasorelaxation through suppression of its colocalization and interaction with large-conductance Ca2+-sensitive K+ (BK) channel proteins in cerebrovascular smooth muscle. These experiments are among the first to demonstrate hypoxic changes in BK subunit abundances in fetal cerebral arteries and also introduce the use of advanced methods of confocal colocalization to study interaction between PKG and its targets.
Collapse
Affiliation(s)
- Richard B Thorpe
- Center for Perinatal Biology and Divisions of Physiology, Pharmacology, and Biochemistry, Loma Linda University School of Medicine, Loma Linda, California
| | - Margaret C Hubbell
- Center for Perinatal Biology and Divisions of Physiology, Pharmacology, and Biochemistry, Loma Linda University School of Medicine, Loma Linda, California
| | - Jinjutha Silpanisong
- Center for Perinatal Biology and Divisions of Physiology, Pharmacology, and Biochemistry, Loma Linda University School of Medicine, Loma Linda, California
| | - James M Williams
- Center for Perinatal Biology and Divisions of Physiology, Pharmacology, and Biochemistry, Loma Linda University School of Medicine, Loma Linda, California
| | - William J Pearce
- Center for Perinatal Biology and Divisions of Physiology, Pharmacology, and Biochemistry, Loma Linda University School of Medicine, Loma Linda, California
| |
Collapse
|
6
|
Pearce WJ. The fetal cerebral circulation: three decades of exploration by the LLU Center for Perinatal Biology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 814:177-91. [PMID: 25015811 DOI: 10.1007/978-1-4939-1031-1_16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
For more than three decades, research programs in the Center of Perinatal Biology have focused on the vascular biology of the fetal cerebral circulation. In the 1980s, research in the Center demonstrated that cerebral autoregulation operated over a narrower pressure range, and was more vulnerable to insults, in fetuses than in adults. Other studies were among the first to establish that compared to adult cerebral arteries, fetal cerebral arteries were more hydrated, contained smaller smooth muscle cells and less connective tissue, and had endothelium less capable of producing NO. Work in the 1990s revealed that pregnancy depressed reactivity to NO in extra-cerebral arteries, but elevated it in cerebral arteries through effects involving changes in cGMP metabolism. Comparative studies verified that fetal lamb cerebral arteries were an excellent model for cerebral arteries from human infants. Biochemical studies demonstrated that cGMP metabolism was dramatically upregulated, but that contraction was far more dependent on calcium influx, in fetal compared to adult cerebral arteries. Further studies established that chronic hypoxia accelerates functional maturation of fetal cerebral arteries, as indicated by increased contractile responses to adrenergic agonists and perivascular adrenergic nerves. In the 2000s, studies of signal transduction established age-dependent roles for PKG, PKC, PKA, ERK, ODC, IP3, myofilament calcium sensitivity, and many other mechanisms. These diverse studies clearly demonstrated that fetal cerebral arteries were functionally quite distinct compared to adult cerebral arteries. In the current decade, research in the Center has expanded to a more molecular focus on epigenetic mechanisms and their role in fetal vascular adaptation to chronic hypoxia, maternal drug abuse, and nutrient deprivation. Overall, the past three decades have transformed thinking about, and understanding of, the fetal cerebral circulation due in no small part to the sustained research efforts by faculty and staff in the Center for Perinatal Biology.
Collapse
Affiliation(s)
- William J Pearce
- Center for Perinatal Biology, Loma Linda University School of Medicine, 92350, Loma Linda, CA, USA,
| |
Collapse
|