1
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Gómez Del Val A, Contreras C, Muñoz M, Sáenz-Medina J, Mohamed M, Rivera L, Sánchez A, Prieto D. Activation of mitoK ATP channels induces penile vasodilation and inhibits mitochondrial respiration and ROS production: Role of NO. Free Radic Biol Med 2024; 217:15-28. [PMID: 38522485 DOI: 10.1016/j.freeradbiomed.2024.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 02/17/2024] [Accepted: 03/12/2024] [Indexed: 03/26/2024]
Abstract
OBJECTIVE Mitochondrial ATP-sensitive K+ (mitoKATP) channels are involved in neuronal and cardiac protection from ischemia and oxidative stress. Penile erection is a neurovascular event mediated by relaxation of the erectile tissue via nitric oxide (NO) released from nerves and endothelium. In the present study, we investigated whether mitoKATP channels play a role in the control of penile vascular tone and mitochondrial dynamics, and the involvement of NO. METHODS The effect of the selective mitoKATP activator BMS191095 was examined on vascular tone, on mitochondrial bioenergetics by real-time measurements with Agilent Seahorse and on ROS production by MitoSOX fluorescence in freshly isolated microarteries. RESULTS BMS191095 and diazoxide relaxed penile arteries, BMS191095 being one order of magnitude more potent. BMS191095-induced relaxations were reduced by mechanical endothelium removal and by inhibitors of the nitric oxide synthase (NOS) and PI3K enzymes. The NO-dependent component of the relaxation to BMS191095 was impaired in penile arteries from insulin resistant obese rats. The blockers of mitoKATP channel 5-HD, sarcolemma KATP (sarcKATP) channel glibenclamide, and large conductance Ca2+-activated K+ (BKCa) channel iberiotoxin, inhibited relaxations to BMS191095 and to the NO donor SNAP. BMS191095 reduced the mitochondrial bioenergetic profile of penile arteries and attenuated mitochondrial ROS production. Blockade of endogenous NO impaired and exogenous NO mimicked, respectively, the inhibitory effects of BMS191095 on basal respiration and oxygen consumed for ATP synthesis. Exogenous NO exhibited dual inhibitory/stimulatory effects on mitochondrial respiration. CONCLUSIONS These results demonstrate that selective activation of mitoKATP channels causes penile vasodilation, attenuates ROS production and inhibits mitochondrial respiration in part by releasing endothelial NO. These mechanisms couple blood flow and metabolism in penile arterial wall and suggest that activation of vascular mitoKATP channels may protect erectile tissue against ischemic injury.
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Affiliation(s)
- Alfonso Gómez Del Val
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Cristina Contreras
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Mercedes Muñoz
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Javier Sáenz-Medina
- Department of Urology, Puerta de Hierro-Majadahonda University Hospital, 28222, Majadahonda, Spain
| | - Mariam Mohamed
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Luis Rivera
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Ana Sánchez
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Dolores Prieto
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain.
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2
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Mahapatra G, Gao Z, Bateman JR, Lockhart SN, Bergstrom J, Piloso JE, Craft S, Molina AJA. Peripheral Blood Cells From Older Adults Exhibit Sex-Associated Differences in Mitochondrial Function. J Gerontol A Biol Sci Med Sci 2024; 79:glae098. [PMID: 38602189 PMCID: PMC11059251 DOI: 10.1093/gerona/glae098] [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: 11/22/2023] [Indexed: 04/12/2024] Open
Abstract
Blood-based mitochondrial bioenergetic profiling is a feasible, economical, and minimally invasive approach that can be used to examine mitochondrial function and energy metabolism in human subjects. In this study, we use 2 complementary respirometric techniques to evaluate mitochondrial bioenergetics in both intact and permeabilized peripheral blood mononuclear cells (PBMCs) and platelets to examine sex dimorphism in mitochondrial function among older adults. Employing equal numbers of PBMCs and platelets to assess mitochondrial bioenergetics, we observe significantly higher respiration rates in female compared to male participants. Mitochondrial bioenergetic differences remain significant after controlling for independent parameters including demographic parameters (age, years of education), and cognitive parameters (mPACC5, COGDX). Our study illustrates that circulating blood cells, immune cells in particular, have distinctly different mitochondrial bioenergetic profiles between females and males. These differences should be taken into account as blood-based bioenergetic profiling is now commonly used to understand the role of mitochondrial bioenergetics in human health and aging.
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Affiliation(s)
- Gargi Mahapatra
- Division of Geriatrics, Gerontology, and Palliative Care, Department of Medicine, University of California San Diego School of Medicine, La Jolla, California, USA
| | - Zhengrong Gao
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - James R Bateman
- Department of Neurology, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - Samuel Neal Lockhart
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - Jaclyn Bergstrom
- Division of Geriatrics, Gerontology, and Palliative Care, Department of Medicine, University of California San Diego School of Medicine, La Jolla, California, USA
| | - Jemima Elizabeth Piloso
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - Suzanne Craft
- Section on Gerontology and Geriatrics, Department of Internal Medicine, Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina, USA
| | - Anthony J A Molina
- Division of Geriatrics, Gerontology, and Palliative Care, Department of Medicine, University of California San Diego School of Medicine, La Jolla, California, USA
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3
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Rebchuk AD, Hill MD, Goyal M, Demchuk A, Coutts SB, Asdaghi N, Dowlatshahi D, Holodinsky JK, Fainardi E, Shankar J, Najm M, Rubiera M, Khaw AV, Qiu W, Menon BK, Field TS. Exploring sex differences for acute ischemic stroke clinical, imaging and thrombus characteristics in the INTERRSeCT study. J Cereb Blood Flow Metab 2023; 43:1803-1809. [PMID: 37459107 PMCID: PMC10581233 DOI: 10.1177/0271678x231189908] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 06/21/2023] [Accepted: 06/24/2023] [Indexed: 10/17/2023]
Abstract
Women, especially following menopause, are known to have worse outcomes following acute ischemic stroke. One primary postulated biological mechanism for worse outcomes in older women is a reduction in the vasculoprotective effects of estrogen. Using the INTERRseCT cohort, a multicentre international observational cohort studying recanalization in acute ischemic stroke, we explored the effects of sex, and modifying effects of age, on neuroradiological predictors of recanalization including robustness of leptomeningeal collaterals, thrombus burden and thrombus permeability. Ordinal regression analyses were used to examine the relationship between sex and each of the neuroradiological markers. Further, we explored both multiplicative and additive interactions between age and sex. All patients (n = 575) from INTERRseCT were included. Mean age was 70.2 years (SD: 13.1) and 48.5% were women. In the unadjusted model, female sex was associated with better collaterals (OR 1.37, 95% CIs: 1.01-1.85), however this relationship was not significant after adjusting for age and relevant comorbidities. There were no significant interactions between age and sex. In a large prospective international cohort, we found no association between sex and radiological predictors of recanalization including leptomeningeal collaterals, thrombus permeability and thrombus burden.
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Affiliation(s)
- Alexander D Rebchuk
- Division of Neurosurgery, University of British Columbia, Vancouver, BC, Canada
| | - Michael D Hill
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Calgary Stroke Program, University of Calgary, Calgary, AB, Canada
| | - Mayank Goyal
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Calgary Stroke Program, University of Calgary, Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
| | - Andrew Demchuk
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Calgary Stroke Program, University of Calgary, Calgary, AB, Canada
| | - Shelagh B Coutts
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Calgary Stroke Program, University of Calgary, Calgary, AB, Canada
| | - Negar Asdaghi
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Dar Dowlatshahi
- School of Epidemiology and Public Health, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
- Department of Medicine (Neurology), University of Ottawa, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Jessalyn K Holodinsky
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Enrico Fainardi
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Jai Shankar
- Department of Radiology, University of Manitoba, Winnipeg, MB, Canada
| | - Mohamed Najm
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Marta Rubiera
- Neurology Department, Hospital Vall d’Hebron, Barcelona, Spain
| | - Alexander V Khaw
- Department of Clinical Neurosciences, University of Western Ontario, London, ON, Canada
| | - Wu Qiu
- Department of Radiology, University of Calgary, Calgary, AB, Canada
| | - Bijoy K Menon
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Calgary Stroke Program, University of Calgary, Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
| | - Thalia S Field
- Division of Neurology, University of British Columbia, Vancouver, BC, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
- Vancouver Stroke Program, Vancouver, BC, Canada
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4
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Hemispheric analysis of mitochondrial Complex I and II activity in the mouse model of ischemia-reperfusion-induced injury. Mitochondrion 2023; 69:147-158. [PMID: 36764500 DOI: 10.1016/j.mito.2023.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 01/27/2023] [Accepted: 02/04/2023] [Indexed: 02/11/2023]
Abstract
Brain ischemia/reperfusion injury results in a variable mixture of cellular damage, but little is known about possible patterns of mitochondrial dysfunction from the scope of hemispheric processes. The current study used high-resolution fluorespirometry to compare ipsi- and contralateral hemispheres' linked respiration and ROS emission after 60-minutes of filament induced middle cerebral artery occlusion (fMCAo) and 2, 24, 72, and 168 h after reperfusion in mice. Our findings highlight that experimental ischemic stroke resulted in higher mitochondrial respiration in the contralateral compared to the ipsilateral hemisphere and highest ROS emission in ipsilateral hemisphere. The largest difference between the ipsilateral and contralateral hemispheres was observed 2 h after reperfusion in Complex I and II ETS state. Oxygen flux returns to near baseline 72 h after reperfusion without any changes thereafter in Complex I and II respiration. Studying the effects of brain mitochondrial functionality after ischemic stroke in each cerebral hemisphere separately provides a better understanding about the molecular and compensatory processes of the contralateral hemisphere, a region of the brain often neglected in stroke research.
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5
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Lackovic J, Jeevakumar V, Burton M, Price TJ, Dussor G. Peroxynitrite Contributes to Behavioral Responses, Increased Trigeminal Excitability, and Changes in Mitochondrial Function in a Preclinical Model of Migraine. J Neurosci 2023; 43:1627-1642. [PMID: 36697259 PMCID: PMC10008057 DOI: 10.1523/jneurosci.1366-22.2023] [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: 07/08/2022] [Revised: 01/17/2023] [Accepted: 01/19/2023] [Indexed: 01/27/2023] Open
Abstract
Administration of a nitric oxide (NO) donor triggers migraine attacks, but the mechanisms by which this occurs are unknown. Reactive nitroxidative species, including NO and peroxynitrite (PN), have been implicated in nociceptive sensitization, and neutralizing PN is antinociceptive. We determined whether PN contributes to nociceptive responses in two distinct models of migraine headache. Female and male mice were subjected to 3 consecutive days of restraint stress or to dural stimulation with the proinflammatory cytokine interleukin-6. Following resolution of the initial poststimulus behavioral responses, animals were tested for hyperalgesic priming using a normally non-noxious dose of the NO donor sodium nitroprusside (SNP) or dural pH 7.0, respectively. We measured periorbital von Frey and grimace responses in both models and measured stress-induced changes in 3-nitrotyrosine (3-NT) expression (a marker for PN activity) and trigeminal ganglia (TGs) mitochondrial function. Additionally, we recorded the neuronal activity of TGs in response to the PN generator SIN-1 [5-amino-3-(4-morpholinyl)-1,2,3-oxadiazolium chloride]. We then tested the effects of the PN decomposition catalysts Fe(III)5,10,15,20-tetrakis(N-methylpyridinium-4-yl) porphyrin (FeTMPyP) and FeTPPS [Fe(III)5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrinato chloride], or the PN scavenger MnTBAP [Mn(III)tetrakis(4-benzoic acid)porphyrin] against these behavioral, molecular, and neuronal changes. Neutralizing PN attenuated stress-induced periorbital hypersensitivity and priming to SNP, with no effect on priming to dural pH 7.0. These compounds also prevented stress-induced increases in 3-NT expression in both the TGs and dura mater, and attenuated TG neuronal hyperexcitability caused by SIN-1. Surprisingly, FeTMPyP attenuated changes in TG mitochondrial function caused by SNP in stressed males only. Together, these data strongly implicate PN in migraine mechanisms and highlight the therapeutic potential of targeting PN.SIGNIFICANCE STATEMENT Among the most reliable experimental triggers of migraine are nitric oxide donors. The mechanisms by which nitric oxide triggers attacks are unclear but may be because of reactive nitroxidative species such as peroxynitrite. Using mouse models of migraine headache, we show that peroxynitrite-modulating compounds attenuate behavioral, neuronal, and molecular changes caused by repeated stress and nitric oxide donors (two of the most common triggers of migraine in humans). Additionally, our results show a sex-specific regulation of mitochondrial function by peroxynitrite following stress, providing novel insight into the ways in which peroxynitrite may contribute to migraine-related mechanisms. Critically, our data underscore the potential in targeting peroxynitrite formation as a novel therapeutic for the treatment of migraine headache.
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Affiliation(s)
- Jacob Lackovic
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Vivek Jeevakumar
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Michael Burton
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Theodore J Price
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
| | - Gregory Dussor
- School of Behavioral and Brain Sciences, The University of Texas at Dallas, Richardson, Texas 75080
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6
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Rutkai I, Merdzo I, Wunnava S, McNulty C, Chandra PK, Katakam PV, Busija DW. Detrimental effects of transient cerebral ischemia on middle cerebral artery mitochondria in female rats. Am J Physiol Heart Circ Physiol 2022; 323:H1343-H1351. [PMID: 36367688 PMCID: PMC9744641 DOI: 10.1152/ajpheart.00346.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 10/20/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022]
Abstract
Mitochondrial numbers and dynamics in brain blood vessels differ between young male and female rats under physiological conditions, but how these differences are affected by stroke is unclear. In males, we found that mitochondrial numbers, possibly due to mitochondrial fission, in large middle cerebral arteries (MCAs) increased following transient middle cerebral artery occlusion (tMCAO). However, mitochondrial effects of stroke on MCAs of female rats have not been studied. To address this disparity, we conducted morphological, biochemical, and functional studies using electron microscopy, Western blot, mitochondrial respiration, and Ca2+ sparks activity measurements in MCAs of female, naïve or sham Sprague-Dawley rats before and 48 h after 90 min of tMCAO. Adverse changes in mitochondrial characteristics and the relationship between mitochondria and sarcoplasmic reticulum (SR) in MCAs were present on both sides. However, mitochondria and mitochondrial/SR associations were often within the range of normal appearance. Mitochondrial protein levels were similar between ipsilateral (ipsi) and contralateral (contra) sides. Nonrespiratory oxygen consumption, maximal respiration, and spare respiratory capacity were similar between ipsi and contra but were reduced compared with sham. Basal respiration, proton leak, and ATP production were similar among MCAs. Ca2+ sparks activity increased in sham and ipsi MCAs exposed to a mitochondrial ATP-sensitive potassium channel opener: diazoxide. Our results show that tMCAO has effects on mitochondria in MCAs on both the ipsi and contra sides. Mitochondrial responses of cerebral arteries to tMCAO in females are substantially different from responses seen previously in male rats suggesting the need for specific sex-based therapies.NEW & NOTEWORTHY We propose that differences in mitochondrial characteristics of males and females, including mitochondrial morphology, respiration, and calcium sparks activity contribute to sex differences in protective and repair mechanisms in response to transient ischemia-reperfusion.
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Affiliation(s)
- Ibolya Rutkai
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
- Tulane Brain Institute, Tulane University, New Orleans, Louisiana
| | - Ivan Merdzo
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Sanjay Wunnava
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Catherine McNulty
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Partha K Chandra
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Prasad V Katakam
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
- Tulane Brain Institute, Tulane University, New Orleans, Louisiana
| | - David W Busija
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
- Tulane Brain Institute, Tulane University, New Orleans, Louisiana
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7
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Damacena de Angelis C, Endoni BT, Nuno D, Lamping K, Ledolter J, Koval OM, Grumbach IM. Sex‐Specific Differences in Endothelial Function Are Driven by Divergent Mitochondrial Ca
2+
Handling. J Am Heart Assoc 2022; 11:e023912. [PMID: 35766269 PMCID: PMC9333382 DOI: 10.1161/jaha.121.023912] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background
Sex‐specific differences in vasodilation are mediated in part by differences in cytosolic Ca
2+
handling, but how variations in mitochondrial Ca
2+
contributes to this effect remains unknown. Here, we investigated the extent to which mitochondrial Ca
2+
entry via the MCU (mitochondrial Ca
2+
uniporter) drives sex differences in vasoreactivity in resistance arteries.
Methods and Results
Enhanced vasodilation of mesenteric resistance arteries to acetylcholine (ACh) was reduced to larger extent in female compared with male mice in 2 genetic models of endothelial MCU ablation. Ex vivo Ca
2+
imaging of mesenteric arteries with Fura‐2AM confirmed higher cytosolic Ca
2+
transients triggered by ACh in arteries from female mice versus male mice. MCU inhibition both strongly reduced cytosolic Ca
2+
transients and blocked mitochondrial Ca
2+
entry. In cultured human aortic endothelial cells, treatment with physiological concentrations of estradiol enhanced cytosolic Ca
2+
transients, Ca
2+
buffering capacity, and mitochondrial Ca
2+
entry in response to ATP or repeat Ca
2+
boluses. Further experiments to establish the mechanisms underlying these effects did not reveal significant differences in the expression of MCU subunits, at either the mRNA or protein level. However, estradiol treatment was associated with an increase in mitochondrial mass, mitochondrial fusion, and the mitochondrial membrane potential and reduced mitochondrial superoxide production.
Conclusions
Our data confirm that mitochondrial function in endothelial cells differs by sex, with female mice having enhanced Ca
2+
uptake capacity, and that these differences are attributable to the presence of more mitochondria and a higher mitochondrial membrane potential in female mice rather than differences in composition of the MCU complex.
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Affiliation(s)
- Celio Damacena de Angelis
- Department of Internal Medicine, Abboud Cardiovascular Research Center University of Iowa Iowa City IA
| | - Benney T. Endoni
- Department of Internal Medicine, Abboud Cardiovascular Research Center University of Iowa Iowa City IA
| | - Daniel Nuno
- Department of Internal Medicine, Abboud Cardiovascular Research Center University of Iowa Iowa City IA
| | - Kathryn Lamping
- Department of Internal Medicine, Abboud Cardiovascular Research Center University of Iowa Iowa City IA
- Department of Pharmacology Carver College of Medicine University of Iowa Iowa City IA
- Iowa City VA Healthcare System Iowa City IA
| | - Johannes Ledolter
- Tippie College of Business University of Iowa Iowa City IA
- College of Liberal Arts and Sciences University of Iowa Iowa City IA
| | - Olha M. Koval
- Department of Internal Medicine, Abboud Cardiovascular Research Center University of Iowa Iowa City IA
| | - Isabella M. Grumbach
- Department of Internal Medicine, Abboud Cardiovascular Research Center University of Iowa Iowa City IA
- Redox and Radiation Biology Program Holden Comprehensive Cancer Center University of Iowa Iowa City IA
- Iowa City VA Healthcare System Iowa City IA
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8
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Chandra PK, Cikic S, Baddoo MC, Rutkai I, Guidry JJ, Flemington EK, Katakam PV, Busija DW. Transcriptome analysis reveals sexual disparities in gene expression in rat brain microvessels. J Cereb Blood Flow Metab 2021; 41:2311-2328. [PMID: 33715494 PMCID: PMC8392780 DOI: 10.1177/0271678x21999553] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Sex is an important determinant of brain microvessels (MVs) function and susceptibility to cerebrovascular and neurological diseases, but underlying mechanisms are unclear. Using high throughput RNA sequencing analysis, we examined differentially expressed (DE) genes in brain MVs from young, male, and female rats. Bioinformatics analysis of the 23,786 identified genes indicates that 298 (1.2%) genes were DE using False Discovery Rate criteria (FDR; p < 0.05), of which 119 (40%) and 179 (60%) genes were abundantly expressed in male and female MVs, respectively. Nucleic acid binding, enzyme modulator, and transcription factor were the top three DE genes, which were more highly expressed in male than female MVs. Synthesis of glycosylphosphatidylinositol (GPI), biosynthesis of GPI-anchored proteins, steroid and cholesterol synthesis, were the top three significantly enriched canonical pathways in male MVs. In contrast, respiratory chain, ribosome, and 3 ́-UTR-mediated translational regulation were the top three enriched canonical pathways in female MVs. Different gene functions of MVs were validated by proteomic analysis and western blotting. Our novel findings reveal major sex disparities in gene expression and canonical pathways of MVs and these differences provide a foundation to study the underlying mechanisms and consequences of sex-dependent differences in cerebrovascular and other neurological diseases.
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Affiliation(s)
- Partha K Chandra
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Sinisa Cikic
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Melody C Baddoo
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA, USA.,Department of Pathology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Ibolya Rutkai
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA.,Department of Pathology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Jessie J Guidry
- Tulane Brain Institute, Tulane University, New Orleans, LA, USA
| | - Erik K Flemington
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA, USA.,Department of Pathology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Prasad Vg Katakam
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA.,Department of Pathology, Tulane University School of Medicine, New Orleans, LA, USA
| | - David W Busija
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA.,Department of Pathology, Tulane University School of Medicine, New Orleans, LA, USA
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9
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Kirkman DL, Robinson AT, Rossman MJ, Seals DR, Edwards DG. Mitochondrial contributions to vascular endothelial dysfunction, arterial stiffness, and cardiovascular diseases. Am J Physiol Heart Circ Physiol 2021; 320:H2080-H2100. [PMID: 33834868 PMCID: PMC8163660 DOI: 10.1152/ajpheart.00917.2020] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 03/12/2021] [Accepted: 04/05/2021] [Indexed: 12/11/2022]
Abstract
Cardiovascular disease (CVD) affects one in three adults and remains the leading cause of death in America. Advancing age is a major risk factor for CVD. Recent plateaus in CVD-related mortality rates in high-income countries after decades of decline highlight a critical need to identify novel therapeutic targets and strategies to mitigate and manage the risk of CVD development and progression. Vascular dysfunction, characterized by endothelial dysfunction and large elastic artery stiffening, is independently associated with an increased CVD risk and incidence and is therefore an attractive target for CVD prevention and management. Vascular mitochondria have emerged as an important player in maintaining vascular homeostasis. As such, age- and disease-related impairments in mitochondrial function contribute to vascular dysfunction and consequent increases in CVD risk. This review outlines the role of mitochondria in vascular function and discusses the ramifications of mitochondrial dysfunction on vascular health in the setting of age and disease. The adverse vascular consequences of increased mitochondrial-derived reactive oxygen species, impaired mitochondrial quality control, and defective mitochondrial calcium cycling are emphasized, in particular. Current evidence for both lifestyle and pharmaceutical mitochondrial-targeted strategies to improve vascular function is also presented.
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Affiliation(s)
- Danielle L Kirkman
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, Virginia
| | | | - Matthew J Rossman
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado
| | - Douglas R Seals
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado
| | - David G Edwards
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware
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10
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Krishnan S, Suarez-Martinez AD, Bagher P, Gonzalez A, Liu R, Murfee WL, Mohandas R. Microvascular dysfunction and kidney disease: Challenges and opportunities? Microcirculation 2021; 28:e12661. [PMID: 33025626 PMCID: PMC9990864 DOI: 10.1111/micc.12661] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 09/18/2020] [Accepted: 09/29/2020] [Indexed: 12/29/2022]
Abstract
Kidneys are highly vascular organs that despite their relatively small size receive 20% of the cardiac output. The highly intricate, delicately organized structure of renal microcirculation is essential to enable renal function and glomerular filtration rate through the local modulation of renal blood flow and intraglomerular pressure. Not surprisingly, the dysregulation of blood flow within the microvessels (abnormal vasoreactivity), fibrosis driven by disordered vascular-renal cross talk, or the loss of renal microvasculature (rarefaction) is associated with kidney disease. In addition, kidney disease can cause microcirculatory dysfunction in distant organs such as the heart and brain, mediated by mechanisms that remain to be elucidated. The objective of this review is to highlight the role of renal microvasculature in kidney disease. The overview will outline the impetus to study renal microvasculature, the bidirectional relationship between kidney disease and microvascular dysfunction, the key pathways driving microvascular diseases such as vasoreactivity, the cell dynamics coordinating fibrosis, and vessel rarefaction. Finally, we will also briefly highlight new therapies targeting the renal microvasculature to improve renal function.
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Affiliation(s)
- Suraj Krishnan
- Division of Nephrology, Hypertension & Transplantation, University of Florida College of Medicine, Gainesville, FL, USA
| | - Ariana D Suarez-Martinez
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Pooneh Bagher
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX, USA
| | - Anjelica Gonzalez
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Ruisheng Liu
- Department of Molecular Pharmacology and Physiology, College of Medicine, University of South Florida, Tampa, FL, USA
| | - Walter L Murfee
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Rajesh Mohandas
- Division of Nephrology, Hypertension & Transplantation, University of Florida College of Medicine, Gainesville, FL, USA
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11
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Cikic S, Chandra PK, Harman JC, Rutkai I, Katakam PV, Guidry JJ, Gidday JM, Busija DW. Sexual differences in mitochondrial and related proteins in rat cerebral microvessels: A proteomic approach. J Cereb Blood Flow Metab 2021; 41:397-412. [PMID: 32241204 PMCID: PMC8370005 DOI: 10.1177/0271678x20915127] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Sex differences in mitochondrial numbers and function are present in large cerebral arteries, but it is unclear whether these differences extend to the microcirculation. We performed an assessment of mitochondria-related proteins in cerebral microvessels (MVs) isolated from young, male and female, Sprague-Dawley rats. MVs composed of arterioles, capillaries, and venules were isolated from the cerebrum and used to perform a 3 versus 3 quantitative, multiplexed proteomics experiment utilizing tandem mass tags (TMT), coupled with liquid chromatography/mass spectrometry (LC/MS). MS data and bioinformatic analyses were performed using Proteome Discoverer version 2.2 and Ingenuity Pathway Analysis. We identified a total of 1969 proteins, of which 1871 were quantified by TMT labels. Sixty-four proteins were expressed significantly (p < 0.05) higher in female samples compared with male samples. Females expressed more mitochondrial proteins involved in energy production, mitochondrial membrane structure, anti-oxidant enzyme proteins, and those involved in fatty acid oxidation. Conversely, males had higher expression levels of mitochondria-destructive proteins. Our findings reveal, for the first time, the full extent of sexual dimorphism in the mitochondrial metabolic protein profiles of MVs, which may contribute to sex-dependent cerebrovascular and neurological pathologies.
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Affiliation(s)
- Sinisa Cikic
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Partha K Chandra
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Jarrod C Harman
- Department of Ophthalmology, Louisiana State University Health Science Center, New Orleans, LA, USA.,Department of Physiology, Louisiana State University Health Science Center, New Orleans, LA, USA.,Neuroscience Center of Excellence, Louisiana State University Health Science Center, New Orleans, LA, USA.,Department of Biochemistry and Molecular Biology, Louisiana State University Health Science Center, New Orleans, LA, USA
| | - Ibolya Rutkai
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA.,Tulane Brain Institute, Tulane University, New Orleans, LA, USA
| | - Prasad Vg Katakam
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA.,Tulane Brain Institute, Tulane University, New Orleans, LA, USA
| | - Jessie J Guidry
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Science Center, New Orleans, LA, USA.,Proteomics Core Facility, Louisiana State University Health Science Center, New Orleans, LA, USA
| | - Jeffrey M Gidday
- Department of Ophthalmology, Louisiana State University Health Science Center, New Orleans, LA, USA.,Department of Physiology, Louisiana State University Health Science Center, New Orleans, LA, USA.,Neuroscience Center of Excellence, Louisiana State University Health Science Center, New Orleans, LA, USA.,Department of Biochemistry and Molecular Biology, Louisiana State University Health Science Center, New Orleans, LA, USA
| | - David W Busija
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA.,Tulane Brain Institute, Tulane University, New Orleans, LA, USA
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12
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Travica N, Ried K, Hudson I, Sali A, Scholey A, Pipingas A. The Contribution of Plasma and Brain Vitamin C on Age and Gender-Related Cognitive Differences: A Mini-Review of the Literature. Front Integr Neurosci 2020; 14:47. [PMID: 32973470 PMCID: PMC7471743 DOI: 10.3389/fnint.2020.00047] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 07/24/2020] [Indexed: 12/14/2022] Open
Abstract
There is increasing evidence that sex differences in the brain may contribute to gender-related behavioral differences, including cognitive function. Literature has revealed gender dimorphisms in cognitive function between males and females. Additionally, several risk factors associated with cognitive decline depend on chronological age. It is well recognized that the process of aging is associated with a decline in cognitive ability and brain function. Various explanations may account for these gender-related cognitive differences and age-associated cognitive changes. Recent investigations have highlighted the importance of vitamin C in maintaining brain health and its association with cognitive function in both cognitively intact and impaired cohorts. The present review explores previous literature that has evaluated differences in plasma/brain vitamin C between genders and during aging. It then assesses whether these age and gender-related differences may affect the relationship between plasma/brain vitamin C and cognition. The purpose of this review was to examine the evidence for a link between plasma/brain vitamin C and cognition and the impact of gender and age on this relationship. Epidemiological studies have frequently shown higher vitamin C plasma concentrations in women. Similarly, aging has been systematically associated with reductions in plasma vitamin C levels. A range of animal studies has demonstrated potential gender and age-related differences in vitamin C brain distribution and utilization. The reviewed literature suggests that gender differences in plasma and brain vitamin C may potentially contribute to differences in gender-associated cognitive ability, particularly while females are pre-menopausal. Additionally, we can propose that age-associated differences in plasma and brain vitamin C may be potentially linked to age-associated cognitive differences, with older cohorts appearing more vulnerable to experience declines in plasma vitamin C concentrations alongside compromised vitamin C brain regulation. This review encourages future investigations to take into account both gender and age when assessing the link between plasma vitamin C concentrations and cognitive function. Further large scale investigations are required to assess whether differences in cognitive function between genders and age groups may be causally attributed to plasma vitamin C status and brain distribution and utilization.
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Affiliation(s)
- Nikolaj Travica
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
- The National Institute of Integrative Medicine, Melbourne, VIC, Australia
| | - Karin Ried
- The National Institute of Integrative Medicine, Melbourne, VIC, Australia
- Discipline of General Practice, University of Adelaide, Adelaide, SA, Australia
- Torrens University, Melbourne, VIC, Australia
| | - Irene Hudson
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
- School of Science, College of Science, Engineering and Health, Mathematical Sciences, Royal Melbourne Institute of Technology (RMIT), Melbourne, VIC, Australia
- School of Mathematical and Physical Science, University of Newcastle, Callaghan, NSW, Australia
| | - Avni Sali
- The National Institute of Integrative Medicine, Melbourne, VIC, Australia
| | - Andrew Scholey
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Andrew Pipingas
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
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13
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Merdzo I, Rutkai I, Sure VNLR, Katakam PVG, Busija DW. Effects of prolonged type 2 diabetes on mitochondrial function in cerebral blood vessels. Am J Physiol Heart Circ Physiol 2019; 317:H1086-H1092. [PMID: 31490734 DOI: 10.1152/ajpheart.00341.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
One of the major characteristics of hyperglycemic states such as type 2 diabetes is increased reactive oxygen species (ROS) generation. Since mitochondria are a major source of ROS, it is vital to understand the involvement of these organelles in the pathogenesis of ROS-mediated conditions. Therefore, we investigated mitochondrial function and ROS production in cerebral blood vessels of 21-wk-old Zucker diabetic fatty obese rats and their lean controls. We have previously shown that in the early stages of insulin resistance, and short periods of type 2 diabetes mellitus, only mild differences exist in mitochondrial function. In the present study, we examined mitochondrial respiration, mitochondrial protein expression, and ROS production in large-surface cerebral arteries. We used 21-wk-old animals exposed to peak glucose levels for 7 wk and compared them with our previous studies on younger diabetic animals. We found that the same segments of mitochondrial respiration (basal respiration and proton leak) were diminished in diabetic groups as they were in younger diabetic animals. Levels of rattin, a rat humanin analog, tended to decrease in the diabetic group but did not reach statistical significance (P = 0.08). Other mitochondrial proteins were unaffected, which might indicate the existence of compensatory mechanisms with extension of this relatively mild form of diabetes. Superoxide levels were significantly higher in large cerebral vessels of diabetic animals compared with the control group. In conclusion, prolonged dietary diabetes leads to stabilization, rather than deterioration, of metabolic status in the cerebral circulation, despite continued overproduction of ROS.NEW & NOTEWORTHY We have characterized for the first time the dynamics of mitochondrial function during the progression of type 2 diabetes mellitus with regard to mitochondrial respiration, protein expression, and reactive oxygen species production. In addition, this is the first measurement of rattin levels in the cerebral vasculature, which could potentially lead to novel treatment options.
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Affiliation(s)
- Ivan Merdzo
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana.,Department of Pharmacology, University of Mostar, School of Medicine, Mostar, Bosnia and Herzegovina
| | - Ibolya Rutkai
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Venkata N L R Sure
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Prasad V G Katakam
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - David W Busija
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
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14
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Gupte R, Brooks W, Vukas R, Pierce J, Harris J. Sex Differences in Traumatic Brain Injury: What We Know and What We Should Know. J Neurotrauma 2019; 36:3063-3091. [PMID: 30794028 PMCID: PMC6818488 DOI: 10.1089/neu.2018.6171] [Citation(s) in RCA: 250] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
There is growing recognition of the problem of male bias in neuroscience research, including in the field of traumatic brain injury (TBI) where fewer women than men are recruited to clinical trials and male rodents have predominantly been used as an experimental injury model. Despite TBI being a leading cause of mortality and disability worldwide, sex differences in pathophysiology and recovery are poorly understood, limiting clinical care and successful drug development. Given growing interest in sex as a biological variable affecting injury outcomes and treatment efficacy, there is a clear need to summarize sex differences in TBI. This scoping review presents an overview of current knowledge of sex differences in TBI and a comparison of human and animal studies. We found that overall, human studies report worse outcomes in women than men, whereas animal studies report better outcomes in females than males. However, closer examination shows that multiple factors including injury severity, sample size, and experimental injury model may differentially interact with sex to affect TBI outcomes. Additionally, we explore how sex differences in mitochondrial structure and function might contribute to possible sex differences in TBI outcomes. We propose recommendations for future investigations of sex differences in TBI, which we hope will lead to improved patient management, prognosis, and translation of therapies from bench to bedside.
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Affiliation(s)
- Raeesa Gupte
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas
| | - William Brooks
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas
- Hoglund Brain Center, University of Kansas Medical Center, Kansas City, Kansas
- The University of Kansas Clinical and Translational Sciences Institute, University of Kansas Medical Center, Kansas City, Kansas
| | - Rachel Vukas
- School of Medicine, Dykes Library of Health Sciences, University of Kansas Medical Center, Kansas City, Kansas
| | - Janet Pierce
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas
| | - Janna Harris
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas
- Hoglund Brain Center, University of Kansas Medical Center, Kansas City, Kansas
- Address correspondence to: Janna Harris, PhD, Hoglund Brain Imaging Center, MS 1052, 3901 Rainbow Boulevard, Kansas City, KS 66160
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15
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Rutkai I, Merdzo I, Wunnava SV, Curtin GT, Katakam PVG, Busija DW. Cerebrovascular function and mitochondrial bioenergetics after ischemia-reperfusion in male rats. J Cereb Blood Flow Metab 2019; 39:1056-1068. [PMID: 29215305 PMCID: PMC6547195 DOI: 10.1177/0271678x17745028] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 11/06/2017] [Indexed: 12/16/2022]
Abstract
The underlying factors promoting increased mitochondrial proteins, mtDNA, and dilation to mitochondrial-specific agents in male rats following tMCAO are not fully elucidated. Our goal was to determine the morphological and functional effects of ischemia/reperfusion (I/R) on mitochondria using electron microscopy, Western blot, mitochondrial oxygen consumption rate (OCR), and Ca2+ sparks activity measurements in middle cerebral arteries (MCAs) from male Sprague Dawley rats (Naïve, tMCAO, Sham). We found a greatly increased OCR in ipsilateral MCAs (IPSI) compared with contralateral (CONTRA), Sham, and Naïve MCAs. Consistent with our earlier findings, the expression of Mitofusin-2 and OPA-1 was significantly decreased in IPSI arteries compared with Sham and Naïve. Mitochondrial morphology was disrupted in vascular smooth muscle, but morphology with normal and perhaps greater numbers of mitochondria were observed in IPSI compared with CONTRA MCAs. Consistently, there were significantly fewer baseline Ca2+ events in IPSI MCAs compared with CONTRA, Sham, and Naïve. Mitochondrial depolarization significantly increased Ca2+ sparks activity in the IPSI, Sham, Naïve, but not in the CONTRA group. Our data indicate that altered mitochondrial structure and function occur in MCAs exposed to I/R and that these changes impact not only OCR but Ca2+ sparks activity in both IPSI and CONTRA MCAs.
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Affiliation(s)
- Ibolya Rutkai
- Department of Pharmacology,
Tulane
University School of Medicine, New Orleans,
LA, USA
| | - Ivan Merdzo
- Department of Pharmacology,
Tulane
University School of Medicine, New Orleans,
LA, USA
- Department of Pharmacology, University
of Mostar School of Medicine, Mostar, Bosnia and Herzegovina
| | - Sanjay V Wunnava
- Department of Pharmacology,
Tulane
University School of Medicine, New Orleans,
LA, USA
| | - Genevieve T Curtin
- Department of Pharmacology,
Tulane
University School of Medicine, New Orleans,
LA, USA
| | - Prasad VG Katakam
- Department of Pharmacology,
Tulane
University School of Medicine, New Orleans,
LA, USA
| | - David W Busija
- Department of Pharmacology,
Tulane
University School of Medicine, New Orleans,
LA, USA
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16
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Role of Gender in Regulation of Redox Homeostasis in Pulmonary Arterial Hypertension. Antioxidants (Basel) 2019; 8:antiox8050135. [PMID: 31100969 PMCID: PMC6562572 DOI: 10.3390/antiox8050135] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 04/18/2019] [Accepted: 05/09/2019] [Indexed: 12/21/2022] Open
Abstract
Pulmonary arterial hypertension (PAH) is one of the diseases with a well-established gender dimorphism. The prevalence of PAH is increased in females with a ratio of 4:1, while poor survival prognosis is associated with the male gender. Nevertheless, the specific contribution of gender in disease development and progression is unclear due to the complex nature of the PAH. Oxidative and nitrosative stresses are important contributors in PAH pathogenesis; however, the role of gender in redox homeostasis has been understudied. This review is aimed to overview the possible sex-specific mechanisms responsible for the regulation of the balance between oxidants and antioxidants in relation to PAH pathobiology.
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17
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Bukiya AN. Fetal Cerebral Artery Mitochondrion as Target of Prenatal Alcohol Exposure. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16091586. [PMID: 31067632 PMCID: PMC6539770 DOI: 10.3390/ijerph16091586] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 04/29/2019] [Accepted: 05/03/2019] [Indexed: 12/14/2022]
Abstract
Prenatal alcohol exposure results in an array of developmental abnormalities known as fetal alcohol spectrum disorders (FASDs). Despite the high prevalence of FASDs, therapeutic interventions against accidental or intended exposure of developing fetuses to alcohol are limited. This review outlines current knowledge about mitochondria in cerebral blood vessels as a potential target for anti-FASDs intervention. First, it describes the multifaceted role of mitochondria in maintaining the cerebral artery diameter as shown in adult tissue. Second, current literature on alcohol-driven damage of mitochondrial morphology and function in several fetal tissues, including liver, heart, and brain is summarized. The functional consequences of alcohol exposure in these organs include morphological enlargement of mitochondria, increased oxidative stress, and alteration of cellular respiration. These studies point to a tissue-specific effect of alcohol on mitochondrial function and a particular vulnerability of fetal mitochondria to alcohol exposure when compared to adult counterparts. Third, recent work from our group describing persistent changes in fetal baboon cerebral artery proteome following three episodes of prenatal alcohol exposure is reviewed. In conclusion, the consequences of prenatal alcohol exposure on cerebral artery mitochondria constitute an open field of investigation and, eventually, a point of therapeutic intervention against FASDs.
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Affiliation(s)
- Anna N Bukiya
- Department Pharmacology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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18
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Ruszkiewicz JA, Miranda-Vizuete A, Tinkov AA, Skalnaya MG, Skalny AV, Tsatsakis A, Aschner M. Sex-Specific Differences in Redox Homeostasis in Brain Norm and Disease. J Mol Neurosci 2019; 67:312-342. [DOI: 10.1007/s12031-018-1241-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 12/10/2018] [Indexed: 12/12/2022]
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19
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Dufurrena Q, Bäck N, Mains R, Hodgson L, Tanowitz H, Mandela P, Eipper B, Kuliawat R. Kalirin/Trio Rho GDP/GTP exchange factors regulate proinsulin and insulin secretion. J Mol Endocrinol 2018; 62:JME-18-0048.R2. [PMID: 30407917 PMCID: PMC6494717 DOI: 10.1530/jme-18-0048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 11/05/2018] [Indexed: 12/31/2022]
Abstract
Key features for progression to pancreatic β-cell failure and disease are loss of glucose responsiveness and an increased ratio of secreted proinsulin to insulin. Proinsulin and insulin are stored in secretory granules (SGs) and the fine-tuning of hormone output requires signal mediated recruitment of select SG populations according to intracellular location and age. The GTPase Rac1 coordinates multiple signaling pathways that specify SG release and Rac1 activity is controlled in part by GDP/GTP exchange factors (GEFs). To explore the function of two large multidomain GEFs, Kalirin and Trio in β-cells, we manipulated their Rac1-specific GEF1 domain activity by using small molecule inhibitors and by genetically ablating Kalirin. We examined age related secretory granule behavior employing radiolabeling protocols. Loss of Kalirin/Trio function attenuated radioactive proinsulin release by reducing constitutive-like secretion and exocytosis of 2-hour old granules. At later chase times or at steady state, Kalirin/Trio manipulations decreased glucose stimulated insulin output. Finally, use of a Rac1 FRET biosensor with cultured β-cell lines, demonstrated that Kalirin/Trio GEF1 activity was required for normal rearrangement of Rac1 to the plasma membrane in response to glucose. Rac1 activation can be evoked by both glucose metabolism and signaling through the incretin glucagon-like peptide 1 (GLP-1) receptor. GLP-1 addition restored Rac1 localization/activity and insulin secretion in the absence of Kalirin, thereby assigning Kalirin's participation to stimulatory glucose signaling.
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Affiliation(s)
- Quinn Dufurrena
- Department of Medicine, Stony Brook University School of Medicine, Stony Brook, NY
| | - Nils Bäck
- Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Richard Mains
- Department of Neuroscience, University of Connecticut Health Center, Farmington, CT
| | - Louis Hodgson
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY
| | - Herbert Tanowitz
- Departments of Pathology, Medicine, Albert Einstein College of Medicine, Bronx, NY
| | | | - Betty Eipper
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT
| | - Regina Kuliawat
- Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY
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20
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Silaidos C, Pilatus U, Grewal R, Matura S, Lienerth B, Pantel J, Eckert GP. Sex-associated differences in mitochondrial function in human peripheral blood mononuclear cells (PBMCs) and brain. Biol Sex Differ 2018; 9:34. [PMID: 30045765 PMCID: PMC6060503 DOI: 10.1186/s13293-018-0193-7] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 07/13/2018] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is the most common form of dementia, and it affects more women than men. Mitochondrial dysfunction (MD) plays a key role in AD, and it is detectable at an early stage of the degenerative process in peripheral tissues, such as peripheral mononuclear blood cells (PBMCs). However, whether these changes are also reflected in cerebral energy metabolism and whether sex-specific differences in mitochondrial function occur are not clear. Therefore, we estimated the correlation between mitochondrial function in PBMCs and brain energy metabolites and examined sex-specific differences in healthy participants to elucidate these issues. METHODS The current pilot study included 9 male and 15 female healthy adults (mean age 30.8 ± 7.1 years). Respiration and activity of mitochondrial respiratory complexes were measured using a Clarke-electrode (Oxygraph-2k system), and adenosine triphosphate (ATP) levels were determined using a bioluminescence-based assay in isolated PBMCs. Citrate synthase activity as a mitochondrial marker was measured using a photometric assay. Concentrations of brain energy metabolites were quantified in the same individuals using 1H-magnetic resonance spectroscopy (MRS). RESULTS We detected sex-associated differences in mitochondrial function. Mitochondrial complexes I, I+II, and IV and uncoupled respiration and electron transport system (ETS) capacity in PBMCs isolated from blood samples of females were significantly (p < 0.05; p < 0.01) higher compared to males. ATP levels in the PBMCs of female participants were approximately 10% higher compared to males. Citrate synthase (CS) activity, a marker of mitochondrial content, was significantly (p < 0.05) higher in females compared to males. Sex-associated differences were also found for brain metabolites. The N-acetylaspartate (NAA) concentration was significantly higher in female participants compared to males in targeted regions. This difference was observed in white matter (WM) and an area with a high percentage (> 50%) of gray matter (GM) (p < 0.05; p < 0.01). The effect sizes indicated a strong influence of sex on these parameters. Sex-associated differences were found in PBMCs and brain, but the determined parameters were not significantly correlated. CONCLUSIONS Our study revealed sex-associated differences in mitochondrial function in healthy participants. The underlying mechanisms must be elucidated in more detail, but our study suggests that mitochondrial function in PBMCs is a feasible surrogate marker to detect differences in mitochondrial function and energy metabolism in humans and it underscores the necessity of sex-specific approaches in therapies that target mitochondrial dysfunction.
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Affiliation(s)
- C. Silaidos
- Nutrition in Prevention and Therapy, Institute for Nutritional Sciences, University of Giessen, Wilhelmstr. 20, 35392 Giessen, Germany
| | - U. Pilatus
- Institute for Neuroradiology, Goethe University Frankfurt, Schleusenweg 2-16, 60528 Frankfurt/Main, Germany
| | - R. Grewal
- Nutrition in Prevention and Therapy, Institute for Nutritional Sciences, University of Giessen, Wilhelmstr. 20, 35392 Giessen, Germany
| | - S. Matura
- Institute of General Practice, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Heinrich-Hoffmann Str. 10, 60528 Frankfurt/Main, Germany
| | - B. Lienerth
- Brain Imaging Centre, Schleusenweg 2-16, 60528 Frankfurt/Main, Germany
| | - J. Pantel
- Institute of General Practice, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt/Main, Germany
| | - G. P. Eckert
- Nutrition in Prevention and Therapy, Institute for Nutritional Sciences, University of Giessen, Wilhelmstr. 20, 35392 Giessen, Germany
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21
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Carvalho C, Moreira PI. Oxidative Stress: A Major Player in Cerebrovascular Alterations Associated to Neurodegenerative Events. Front Physiol 2018; 9:806. [PMID: 30018565 PMCID: PMC6037979 DOI: 10.3389/fphys.2018.00806] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 06/08/2018] [Indexed: 12/19/2022] Open
Abstract
The brain is one of the most exquisite organs in the body with high metabolic demands, and requires a tight regulation of the surrounding environment. This tight control is exerted by the neurovascular unit (NVU) comprising different cell types, where endothelial cells play the commander-in-chief role. Thus, it is assumable that even slight perturbations in NVU might affect, in some cases irreversibly, brain homeostasis and health. In this line, recent findings support the two-hit vascular hypothesis for neurodegenerative conditions, where vascular dysfunction underlies the development of neurodegenerative diseases, such as Alzheimer’s disease (AD). Knowing that endothelial cells are rich in mitochondria and nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, two major reactive oxygen species (ROS) sources, this review aims to gather information on how oxidative stress is in the front line of vascular alterations observed in brain aging and neurodegenerative conditions, particularly AD. Also, a brief discussion about the therapeutic strategies aimed to protect against cerebrovascular diseases is included.
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Affiliation(s)
- Cristina Carvalho
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Paula I Moreira
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Laboratory of Physiology, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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Mitochondria: a central target for sex differences in pathologies. Clin Sci (Lond) 2017; 131:803-822. [PMID: 28424375 DOI: 10.1042/cs20160485] [Citation(s) in RCA: 206] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 01/14/2017] [Accepted: 01/23/2017] [Indexed: 12/21/2022]
Abstract
It is increasingly acknowledged that a sex and gender specificity affects the occurrence, development, and consequence of a plethora of pathologies. Mitochondria are considered as the powerhouse of the cell because they produce the majority of energy-rich phosphate bonds in the form of adenosine tri-phosphate (ATP) but they also participate in many other functions like steroid hormone synthesis, reactive oxygen species (ROS) production, ionic regulation, and cell death. Adequate cellular energy supply and survival depend on mitochondrial life cycle, a process involving mitochondrial biogenesis, dynamics, and quality control via mitophagy. It appears that mitochondria are the place of marked sexual dimorphism involving mainly oxidative capacities, calcium handling, and resistance to oxidative stress. In turn, sex hormones regulate mitochondrial function and biogenesis. Mutations in genes encoding mitochondrial proteins are the origin of serious mitochondrial genetic diseases. Mitochondrial dysfunction is also an important parameter for a large panel of pathologies including neuromuscular disorders, encephalopathies, cardiovascular diseases (CVDs), metabolic disorders, neuropathies, renal dysfunction etc. Many of these pathologies present sex/gender specificity. Here we review the sexual dimorphism of mitochondria from different tissues and how this dimorphism takes part in the sex specificity of important pathologies mainly CVDs and neurological disorders.
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Merdzo I, Rutkai I, Sure VNLR, McNulty CA, Katakam PVG, Busija DW. Impaired Mitochondrial Respiration in Large Cerebral Arteries of Rats with Type 2 Diabetes. J Vasc Res 2017; 54:1-12. [PMID: 28095372 DOI: 10.1159/000454812] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 11/27/2016] [Indexed: 12/19/2022] Open
Abstract
Mitochondrial dysfunction has been suggested as a potential underlying cause of pathological conditions associated with type 2 diabetes (T2DM). We have previously shown that mitochondrial respiration and mitochondrial protein levels were similar in the large cerebral arteries of insulin-resistant Zucker obese rats and their lean controls. In this study, we extend our investigations into the mitochondrial dynamics of the cerebral vasculature of 14-week-old Zucker diabetic fatty obese (ZDFO) rats with early T2DM. Body weight and blood glucose levels were significantly higher in the ZDFO group, and basal mitochondrial respiration and proton leak were significantly decreased in the large cerebral arteries of the ZDFO rats compared with the lean controls (ZDFL). The expression of the mitochondrial proteins total manganese superoxide dismutase (MnSOD) and voltage-dependent anion channel (VDAC) were significantly lower in the cerebral microvessels, and acetylated MnSOD levels were significantly reduced in the large arteries of the ZDFO group. Additionally, superoxide production was significantly increased in the microvessels of the ZDFO group. Despite evidence of increased oxidative stress in ZDFO, exogenous SOD was not able to restore mitochondrial respiration in the ZDFO rats. Our results show, for the first time, that mitochondrial respiration and protein levels are compromised during the early stages of T2DM.
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Affiliation(s)
- Ivan Merdzo
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
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Busija DW, Rutkai I, Dutta S, Katakam PV. Role of Mitochondria in Cerebral Vascular Function: Energy Production, Cellular Protection, and Regulation of Vascular Tone. Compr Physiol 2016; 6:1529-48. [PMID: 27347901 DOI: 10.1002/cphy.c150051] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mitochondria not only produce energy in the form of ATP to support the activities of cells comprising the neurovascular unit, but mitochondrial events, such as depolarization and/or ROS release, also initiate signaling events which protect the endothelium and neurons against lethal stresses via pre-/postconditioning as well as promote changes in cerebral vascular tone. Mitochondrial depolarization in vascular smooth muscle (VSM), via pharmacological activation of the ATP-dependent potassium channels on the inner mitochondrial membrane (mitoKATP channels), leads to vasorelaxation through generation of calcium sparks by the sarcoplasmic reticulum and subsequent downstream signaling mechanisms. Increased release of ROS by mitochondria has similar effects. Relaxation of VSM can also be indirectly achieved via actions of nitric oxide (NO) and other vasoactive agents produced by endothelium, perivascular and parenchymal nerves, and astroglia following mitochondrial activation. Additionally, NO production following mitochondrial activation is involved in neuronal preconditioning. Cerebral arteries from female rats have greater mitochondrial mass and respiration and enhanced cerebral arterial dilation to mitochondrial activators. Preexisting chronic conditions such as insulin resistance and/or diabetes impair mitoKATP channel relaxation of cerebral arteries and preconditioning. Surprisingly, mitoKATP channel function after transient ischemia appears to be retained in the endothelium of large cerebral arteries despite generalized cerebral vascular dysfunction. Thus, mitochondrial mechanisms may represent the elusive signaling link between metabolic rate and blood flow as well as mediators of vascular change according to physiological status. Mitochondrial mechanisms are an important, but underutilized target for improving vascular function and decreasing brain injury in stroke patients. © 2016 American Physiological Society. Compr Physiol 6:1529-1548, 2016.
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Affiliation(s)
- David W Busija
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Ibolya Rutkai
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Somhrita Dutta
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Prasad V Katakam
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana, USA
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Katakam PVG, Dutta S, Sure VN, Grovenburg SM, Gordon AO, Peterson NR, Rutkai I, Busija DW. Depolarization of mitochondria in neurons promotes activation of nitric oxide synthase and generation of nitric oxide. Am J Physiol Heart Circ Physiol 2016; 310:H1097-106. [PMID: 26945078 DOI: 10.1152/ajpheart.00759.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 02/07/2016] [Indexed: 11/22/2022]
Abstract
The diverse signaling events following mitochondrial depolarization in neurons are not clear. We examined for the first time the effects of mitochondrial depolarization on mitochondrial function, intracellular calcium, neuronal nitric oxide synthase (nNOS) activation, and nitric oxide (NO) production in cultured neurons and perivascular nerves. Cultured rat primary cortical neurons were studied on 7-10 days in vitro, and endothelium-denuded cerebral arteries of adult Sprague-Dawley rats were studied ex vivo. Diazoxide and BMS-191095 (BMS), activators of mitochondrial KATP channels, depolarized mitochondria in cultured neurons and increased cytosolic calcium levels. However, the mitochondrial oxygen consumption rate was unaffected by mitochondrial depolarization. In addition, diazoxide and BMS not only increased the nNOS phosphorylation at positive regulatory serine 1417 but also decreased nNOS phosphorylation at negative regulatory serine 847. Furthermore, diazoxide and BMS increased NO production in cultured neurons measured with both fluorescence microscopy and electron spin resonance spectroscopy, which was sensitive to inhibition by the selective nNOS inhibitor 7-nitroindazole (7-NI). Diazoxide also protected cultured neurons against oxygen-glucose deprivation, which was blocked by NOS inhibition and rescued by NO donors. Finally, BMS induced vasodilation of endothelium denuded, freshly isolated cerebral arteries that was diminished by 7-NI and tetrodotoxin. Thus pharmacological depolarization of mitochondria promotes activation of nNOS leading to generation of NO in cultured neurons and endothelium-denuded arteries. Mitochondrial-induced NO production leads to increased cellular resistance to lethal stress by cultured neurons and to vasodilation of denuded cerebral arteries.
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Affiliation(s)
- Prasad V G Katakam
- Department of Pharmacology, Tulane University School of Medicine, Tulane University, New Orleans, Louisiana
| | - Somhrita Dutta
- Department of Pharmacology, Tulane University School of Medicine, Tulane University, New Orleans, Louisiana
| | - Venkata N Sure
- Department of Pharmacology, Tulane University School of Medicine, Tulane University, New Orleans, Louisiana
| | - Samuel M Grovenburg
- Department of Pharmacology, Tulane University School of Medicine, Tulane University, New Orleans, Louisiana
| | - Angellica O Gordon
- Department of Pharmacology, Tulane University School of Medicine, Tulane University, New Orleans, Louisiana
| | - Nicholas R Peterson
- Department of Pharmacology, Tulane University School of Medicine, Tulane University, New Orleans, Louisiana
| | - Ibolya Rutkai
- Department of Pharmacology, Tulane University School of Medicine, Tulane University, New Orleans, Louisiana
| | - David W Busija
- Department of Pharmacology, Tulane University School of Medicine, Tulane University, New Orleans, Louisiana
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Merdzo I, Rutkai I, Tokes T, Sure VNLR, Katakam PVG, Busija DW. The mitochondrial function of the cerebral vasculature in insulin-resistant Zucker obese rats. Am J Physiol Heart Circ Physiol 2016; 310:H830-8. [PMID: 26873973 DOI: 10.1152/ajpheart.00964.2015] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/03/2016] [Indexed: 12/24/2022]
Abstract
Little is known about mitochondrial functioning in the cerebral vasculature during insulin resistance (IR). We examined mitochondrial respiration in isolated cerebral arteries of male Zucker obese (ZO) rats and phenotypically normal Zucker lean (ZL) rats using the Seahorse XFe24 analyzer. We investigated mitochondrial morphology in cerebral blood vessels as well as mitochondrial and nonmitochondrial protein expression levels in cerebral arteries and microvessels. We also measured reactive oxygen species (ROS) levels in cerebral microvessels. Under basal conditions, the mitochondrial respiration components (nonmitochondrial respiration, basal respiration, ATP production, proton leak, and spare respiratory capacity) showed similar levels among the ZL and ZO groups with the exception of maximal respiration, which was higher in the ZO group. We examined the role of nitric oxide by measuring mitochondrial respiration following inhibition of nitric oxide synthase with N(ω)-nitro-l-arginine methyl ester (l-NAME) and mitochondrial activation after administration of diazoxide (DZ). Both ZL and ZO groups showed similar responses to these stimuli with minor variations.l-NAME significantly increased the proton leak, and DZ decreased nonmitochondrial respiration in the ZL group. Other components were not affected. Mitochondrial morphology and distribution within vascular smooth muscle and endothelium as well as mitochondrial protein levels were similar in the arteries and microvessels of both groups. Endothelial nitric oxide synthase (eNOS) and ROS levels were increased in cerebral microvessels of the ZO. Our study suggests that mitochondrial function is not significantly altered in the cerebral vasculature of young ZO rats, but increased ROS production might be due to increased eNOS in the cerebral microcirculation during IR.
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Affiliation(s)
- Ivan Merdzo
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Ibolya Rutkai
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Tunde Tokes
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Venkata N L R Sure
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Prasad V G Katakam
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
| | - David W Busija
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana
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