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Durr AJ, Hathaway QA, Kunovac A, Taylor AD, Pinti MV, Rizwan S, Shepherd DL, Cook CC, Fink GK, Hollander JM. Manipulation of the miR-378a/mt-ATP6 regulatory axis rescues ATP synthase in the diabetic heart and offers a novel role for lncRNA Kcnq1ot1. Am J Physiol Cell Physiol 2022; 322:C482-C495. [PMID: 35108116 PMCID: PMC8917913 DOI: 10.1152/ajpcell.00446.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Diabetes mellitus has been linked to an increase in mitochondrial microRNA-378a (miR-378a) content. Enhanced miR-378a content has been associated with a reduction in mitochondrial genome-encoded mt-ATP6 abundance, supporting the hypothesis that miR-378a inhibition may be a therapeutic option for maintaining ATP synthase functionality during diabetes mellitus. Evidence also suggests that long noncoding RNAs (lncRNAs), including lncRNA potassium voltage-gated channel subfamily Q member 1 overlapping transcript 1 (Kcnq1ot1), participate in regulatory axes with microRNAs (miRs). Prediction analyses indicate that Kcnq1ot1 has the potential to bind miR-378a. This study aimed to determine if loss of miR-378a in a genetic mouse model could ameliorate cardiac dysfunction in type 2 diabetes mellitus (T2DM) and to ascertain whether Kcnq1ot1 interacts with miR-378a to impact ATP synthase functionality by preserving mt-ATP6 levels. MiR-378a was significantly higher in patients with T2DM and 25-wk-old Db/Db mouse mitochondria, whereas mt-ATP6 and Kcnq1ot1 levels were significantly reduced when compared with controls. Twenty-five-week-old miR-378a knockout Db/Db mice displayed preserved mt-ATP6 and ATP synthase protein content, ATP synthase activity, and preserved cardiac function, implicating miR-378a as a potential therapeutic target in T2DM. Assessments following overexpression of the 500-bp Kcnq1ot1 fragment in established mouse cardiomyocyte cell line (HL-1) cardiomyocytes overexpressing miR-378a revealed that Kcnq1ot1 may bind and significantly reduce miR-378a levels, and rescue mt-ATP6 and ATP synthase protein content. Together, these data suggest that Kcnq1ot1 and miR-378a may act as constituents in an axis that regulates mt-ATP6 content, and that manipulation of this axis may provide benefit to ATP synthase functionality in type 2 diabetic heart.
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Affiliation(s)
- Andrya J. Durr
- 1Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia,2Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Quincy A. Hathaway
- 1Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia,2Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia,3Center for Inhalation Toxicology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Amina Kunovac
- 1Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia,2Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia,3Center for Inhalation Toxicology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Andrew D. Taylor
- 1Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia,2Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Mark V. Pinti
- 2Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia,4West Virginia University School of Pharmacy, Morgantown, West Virginia,5Department of Physiology and Pharmacology, West Virginia
University School of Medicine, Morgantown, West Virginia
| | - Saira Rizwan
- 1Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia,2Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Danielle L. Shepherd
- 1Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Chris C. Cook
- 6Cardiovascular and Thoracic Surgery, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Garrett K. Fink
- 1Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - John M. Hollander
- 1Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia,2Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia,3Center for Inhalation Toxicology, West Virginia University School of Medicine, Morgantown, West Virginia
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Durr AJ, Hathaway QA, Kunovac A, Taylor AD, Pinti MV, McLaughlin SL, Shepherd DL, Singh AK, Hollander JM. MicroRNA‐378a Loss Enhances Mitochondrial Bioenergetics and Lessens Cardiac Contractile Dysfunction in the Type 2 Diabetic Heart. FASEB J 2020; 34:1-1. [DOI: 10.1096/fasebj.2020.34.s1.02941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
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Myers MJ, Shepherd DL, Durr AJ, Stanton DS, Mohamed JS, Hollander JM, Alway SE. The role of SIRT1 in skeletal muscle function and repair of older mice. J Cachexia Sarcopenia Muscle 2019; 10:929-949. [PMID: 31197980 PMCID: PMC6711423 DOI: 10.1002/jcsm.12437] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 03/21/2019] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Sirtuin 1 (SIRT1) is a NAD+ sensitive deacetylase that has been linked to longevity and has been suggested to confer beneficial effects that counter aging-associated deterioration. Muscle repair is dependent upon satellite cell function, which is reported to be reduced with aging; however, it is not known if this is linked to an aging-suppression of SIRT1. This study tested the hypothesis that Sirtuin 1 (SIRT1) overexpression would increase the extent of muscle repair and muscle function in older mice. METHODS We examined satellite cell dependent repair in tibialis anterior, gastrocnemius, and soleus muscles of 13 young wild-type mice (20-30 weeks) and 49 older (80+ weeks) mice that were controls (n = 13), overexpressed SIRT1 in skeletal muscle (n = 14), and had a skeletal muscle SIRT1 knockout (n = 12) or a satellite cell SIRT1 knockout (n = 10). Acute muscle injury was induced by injection of cardiotoxin (CTX), and phosphate-buffered saline was used as a vector control. Plantarflexor muscle force and fatigue were evaluated before or 21 days after CTX injection. Satellite cell proliferation and mitochondrial function were also evaluated in undamaged muscles. RESULTS Maximal muscle force was significantly lower in control muscles of older satellite cell knockout SIRT1 mice compared to young adult wild-type (YWT) mice (P < 0.001). Mean contraction force at 40 Hz stimulation was significantly greater after recovery from CTX injury in older mice that overexpressed muscle SIRT1 than age-matched SIRT1 knockout mice (P < 0.05). SIRT1 muscle knockout models (P < 0.05) had greater levels of p53 (P < 0.05 MKO, P < 0.001 OE) in CTX-damaged tissues as compared to YWT CTX mice. SIRT1 overexpression with co-expression of p53 was associated with increased fatigue resistance and increased force potentiation during repeated contractions as compared to wild-type or SIRT1 knockout models (P < 0.001). Muscle structure and mitochondrial function were not different between the groups, but proliferation of satellite cells was significantly greater in older mice with SIRT1 muscle knockout (P < 0.05), but not older SIRT1 satellite cell knockout models, in vitro, although this effect was attenuated in vivo after 21 days of recovery. CONCLUSIONS The data suggest skeletal muscle structure, function, and recovery after CTX-induced injury are not significantly influenced by gain or loss of SIRT1 abundance alone in skeletal muscle; however, muscle function is impaired by ablation of SIRT1 in satellite cells. SIRT1 appears to interact with p53 to improve muscle fatigue resistance after repair from muscle injury.
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Affiliation(s)
- Matthew J. Myers
- Laboratory of Muscle Biology and SarcopeniaWest Virginia University School of MedicineMorgantownUSA
| | - Danielle L. Shepherd
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory SciencesWest Virginia University School of MedicineMorgantownUSA
| | - Andrya J. Durr
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory SciencesWest Virginia University School of MedicineMorgantownUSA
| | - David S. Stanton
- Laboratory of Muscle Biology and SarcopeniaWest Virginia University School of MedicineMorgantownUSA
| | - Junaith S. Mohamed
- Laboratory of Muscle Biology and SarcopeniaWest Virginia University School of MedicineMorgantownUSA
- Laboratory of Nerve and Muscle, Department of Clinical Laboratory Sciences, College of Health ProfessionsUniversity of Tennessee Health Science CenterMemphisUSA
| | - John M. Hollander
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory SciencesWest Virginia University School of MedicineMorgantownUSA
| | - Stephen E. Alway
- Laboratory of Muscle Biology and SarcopeniaWest Virginia University School of MedicineMorgantownUSA
- Laboratory of Muscle Biology and Sarcopenia, Department of Physical Therapy, College of Health ProfessionsUniversity of Tennessee Health Science CenterMemphisUSA
- Department of Physiology, College of MedicineUniversity of Tennessee Health Science CenterMemphisUSA
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Durr AJ, Hathaway QA, Pinti MV, Shepherd DL, Kunovac A, Fink GK, Hollander JM. Stress Strain Speckle‐Tacking Segmental Analysis Reveals Early Indications of Diastolic Dysfunction in a Type 2 Mouse Model of Diabetes Mellitus. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.828.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Andrya J Durr
- Exercise PhysiologyWest Virginia UniversityMorgantownWV
| | | | | | | | - Amina Kunovac
- Exercise PhysiologyWest Virginia UniversityMorgantownWV
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Hathaway QA, Durr AJ, Shepherd DL, Pinti MV, Brandebura AN, Nichols CE, Kunovac A, Goldsmith WT, Friend SA, Abukabda AB, Fink GK, Nurkiewicz TR, Hollander JM. miRNA-378a as a key regulator of cardiovascular health following engineered nanomaterial inhalation exposure. Nanotoxicology 2019; 13:644-663. [PMID: 30704319 DOI: 10.1080/17435390.2019.1570372] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Nano-titanium dioxide (nano-TiO2), though one of the most utilized and produced engineered nanomaterials (ENMs), diminishes cardiovascular function through dysregulation of metabolism and mitochondrial bioenergetics following inhalation exposure. The molecular mechanisms governing this cardiac dysfunction remain largely unknown. The purpose of this study was to elucidate molecular mediators that connect nano-TiO2 exposure with impaired cardiac function. Specifically, we were interested in the role of microRNA (miRNA) expression in the resulting dysfunction. Not only are miRNA global regulators of gene expression, but also miRNA-based therapeutics provide a realistic treatment modality. Wild type and MiRNA-378a knockout mice were exposed to nano-TiO2 with an aerodynamic diameter of 182 ± 1.70 nm and a mass concentration of 11.09 mg/m3 for 4 h. Cardiac function, utilizing the Vevo 2100 Imaging System, electron transport chain complex activities, and mitochondrial respiration assessed cardiac and mitochondrial function. Immunoblotting and qPCR examined molecular targets of miRNA-378a. MiRNA-378a-3p expression was increased 48 h post inhalation exposure to nano-TiO2. Knockout of miRNA-378a preserved cardiac function following exposure as revealed by preserved E/A ratio and E/SR ratio. In knockout animals, complex I, III, and IV activities (∼2- to 6-fold) and fatty acid respiration (∼5-fold) were significantly increased. MiRNA-378a regulated proteins involved in mitochondrial fusion, transcription, and fatty acid metabolism. MiRNA-378a-3p acts as a negative regulator of mitochondrial metabolic and biogenesis pathways. MiRNA-378a knockout animals provide a protective effect against nano-TiO2 inhalation exposure by altering mitochondrial structure and function. This is the first study to manipulate a miRNA to attenuate the effects of ENM exposure.
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Affiliation(s)
- Quincy A Hathaway
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,b Mitochondria, Metabolism & Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA.,c Toxicology Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Andrya J Durr
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,b Mitochondria, Metabolism & Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Danielle L Shepherd
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,b Mitochondria, Metabolism & Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Mark V Pinti
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,b Mitochondria, Metabolism & Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Ashley N Brandebura
- d Rockefeller Neuroscience Institute , West Virginia University School of Medicine , Morgantown , WV , USA.,e Department of Biochemistry , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Cody E Nichols
- f Immunity, Inflammation, and Disease Laboratory , National Institute of Environmental Health Sciences , Research Triangle Park , NC , USA
| | - Amina Kunovac
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,b Mitochondria, Metabolism & Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
| | - William T Goldsmith
- c Toxicology Working Group , West Virginia University School of Medicine , Morgantown , WV , USA.,g Department of Physiology, Pharmacology & Neuroscience , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Sherri A Friend
- h CDC , National Institute for Occupational Safety and Health , Morgantown , WV , USA
| | - Alaeddin B Abukabda
- c Toxicology Working Group , West Virginia University School of Medicine , Morgantown , WV , USA.,g Department of Physiology, Pharmacology & Neuroscience , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Garrett K Fink
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Timothy R Nurkiewicz
- c Toxicology Working Group , West Virginia University School of Medicine , Morgantown , WV , USA.,g Department of Physiology, Pharmacology & Neuroscience , West Virginia University School of Medicine , Morgantown , WV , USA
| | - John M Hollander
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,b Mitochondria, Metabolism & Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
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Shepherd DL, Hathaway QA, Nichols CE, Durr AJ, Pinti MV, Hughes KM, Kunovac A, Stine SM, Hollander JM. Mitochondrial proteome disruption in the diabetic heart through targeted epigenetic regulation at the mitochondrial heat shock protein 70 (mtHsp70) nuclear locus. J Mol Cell Cardiol 2018; 119:104-115. [PMID: 29733819 DOI: 10.1016/j.yjmcc.2018.04.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 04/26/2018] [Accepted: 04/28/2018] [Indexed: 01/17/2023]
Abstract
>99% of the mitochondrial proteome is nuclear-encoded. The mitochondrion relies on a coordinated multi-complex process for nuclear genome-encoded mitochondrial protein import. Mitochondrial heat shock protein 70 (mtHsp70) is a key component of this process and a central constituent of the protein import motor. Type 2 diabetes mellitus (T2DM) disrupts mitochondrial proteomic signature which is associated with decreased protein import efficiency. The goal of this study was to manipulate the mitochondrial protein import process through targeted restoration of mtHsp70, in an effort to restore proteomic signature and mitochondrial function in the T2DM heart. A novel line of cardiac-specific mtHsp70 transgenic mice on the db/db background were generated and cardiac mitochondrial subpopulations were isolated with proteomic evaluation and mitochondrial function assessed. MicroRNA and epigenetic regulation of the mtHsp70 gene during T2DM were also evaluated. MtHsp70 overexpression restored cardiac function and nuclear-encoded mitochondrial protein import, contributing to a beneficial impact on proteome signature and enhanced mitochondrial function during T2DM. Further, transcriptional repression at the mtHsp70 genomic locus through increased localization of H3K27me3 during T2DM insult was observed. Our results suggest that restoration of a key protein import constituent, mtHsp70, provides therapeutic benefit through attenuation of mitochondrial and contractile dysfunction in T2DM.
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Affiliation(s)
- Danielle L Shepherd
- Division of Exercise Physiology, Mitochondrial, Metabolism and Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26505, United States
| | - Quincy A Hathaway
- Division of Exercise Physiology, Mitochondrial, Metabolism and Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26505, United States
| | - Cody E Nichols
- Division of Exercise Physiology, Mitochondrial, Metabolism and Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26505, United States
| | - Andrya J Durr
- Division of Exercise Physiology, Mitochondrial, Metabolism and Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26505, United States
| | - Mark V Pinti
- Division of Exercise Physiology, Mitochondrial, Metabolism and Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26505, United States
| | - Kristen M Hughes
- Division of Exercise Physiology, Mitochondrial, Metabolism and Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26505, United States
| | - Amina Kunovac
- Division of Exercise Physiology, Mitochondrial, Metabolism and Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26505, United States
| | - Seth M Stine
- Division of Exercise Physiology, Mitochondrial, Metabolism and Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26505, United States
| | - John M Hollander
- Division of Exercise Physiology, Mitochondrial, Metabolism and Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26505, United States.
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Stapleton PA, Hathaway QA, Nichols CE, Abukabda AB, Pinti MV, Shepherd DL, McBride CR, Yi J, Castranova VC, Hollander JM, Nurkiewicz TR. Maternal engineered nanomaterial inhalation during gestation alters the fetal transcriptome. Part Fibre Toxicol 2018; 15:3. [PMID: 29321036 PMCID: PMC5763571 DOI: 10.1186/s12989-017-0239-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 12/21/2017] [Indexed: 01/19/2023] Open
Abstract
Background The integration of engineered nanomaterials (ENM) is well-established and widespread in clinical, commercial, and domestic applications. Cardiovascular dysfunctions have been reported in adult populations after exposure to a variety of ENM. As the diversity of these exposures continues to increase, the fetal ramifications of maternal exposures have yet to be determined. We, and others, have explored the consequences of ENM inhalation during gestation and identified many cardiovascular and metabolic outcomes in the F1 generation. The purpose of these studies was to identify genetic alterations in the F1 generation of Sprague-Dawley rats that result from maternal ENM inhalation during gestation. Pregnant dams were exposed to nano-titanium dioxide (nano-TiO2) aerosols (10 ± 0.5 mg/m3) for 7-8 days (calculated, cumulative lung deposition = 217 ± 1 μg) and on GD (gestational day) 20 fetal hearts were isolated. DNA was extracted and immunoprecipitated with modified chromatin marks histone 3 lysine 4 tri-methylation (H3K4me3) and histone 3 lysine 27 tri-methylation (H3K27me3). Following chromatin immunoprecipitation (ChIP), DNA fragments were sequenced. RNA from fetal hearts was purified and prepared for RNA sequencing and transcriptomic analysis. Ingenuity Pathway Analysis (IPA) was then used to identify pathways most modified by gestational ENM exposure. Results The results of the sequencing experiments provide initial evidence that significant epigenetic and transcriptomic changes occur in the cardiac tissue of maternal nano-TiO2 exposed progeny. The most notable alterations in major biologic systems included immune adaptation and organismal growth. Changes in normal physiology were linked with other tissues, including liver and kidneys. Conclusions These results are the first evidence that maternal ENM inhalation impacts the fetal epigenome. Electronic supplementary material The online version of this article (10.1186/s12989-017-0239-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- P A Stapleton
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ, USA.,Environmental and Occupational Health Sciences Institute, Piscataway, NJ, USA
| | - Q A Hathaway
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV, USA.,Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV, USA.,Toxicology Working Group, West Virginia University School of Medicine, Morgantown, WV, USA
| | - C E Nichols
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - A B Abukabda
- Toxicology Working Group, West Virginia University School of Medicine, Morgantown, WV, USA.,Department of Pharmaceutical Sciences, West Virginia University School of Pharmacy, Morgantown, USA
| | - M V Pinti
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV, USA.,Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV, USA
| | - D L Shepherd
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV, USA.,Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV, USA
| | - C R McBride
- Toxicology Working Group, West Virginia University School of Medicine, Morgantown, WV, USA.,Department of Physiology, Pharmacology, and Neuroscience, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, 1 Medical Center Drive, Morgantown, WV, 26506-9229, USA
| | - J Yi
- Toxicology Working Group, West Virginia University School of Medicine, Morgantown, WV, USA.,Department of Physiology, Pharmacology, and Neuroscience, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, 1 Medical Center Drive, Morgantown, WV, 26506-9229, USA
| | - V C Castranova
- Toxicology Working Group, West Virginia University School of Medicine, Morgantown, WV, USA.,Department of Pharmaceutical Sciences, West Virginia University School of Pharmacy, Morgantown, USA
| | - J M Hollander
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV, USA.,Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV, USA.,Toxicology Working Group, West Virginia University School of Medicine, Morgantown, WV, USA
| | - T R Nurkiewicz
- Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV, USA. .,Toxicology Working Group, West Virginia University School of Medicine, Morgantown, WV, USA. .,Department of Physiology, Pharmacology, and Neuroscience, Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, 1 Medical Center Drive, Morgantown, WV, 26506-9229, USA.
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Nichols CE, Shepherd DL, Hathaway QA, Durr AJ, Thapa D, Abukabda A, Yi J, Nurkiewicz TR, Hollander JM. Reactive oxygen species damage drives cardiac and mitochondrial dysfunction following acute nano-titanium dioxide inhalation exposure. Nanotoxicology 2017; 12:32-48. [PMID: 29243970 DOI: 10.1080/17435390.2017.1416202] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Nanotechnology offers innovation in products from cosmetics to drug delivery, leading to increased engineered nanomaterial (ENM) exposure. Unfortunately, health impacts of ENM are not fully realized. Titanium dioxide (TiO2) is among the most widely produced ENM due to its use in numerous applications. Extrapulmonary effects following pulmonary exposure have been identified and may involve reactive oxygen species (ROS). The goal of this study was to determine the extent of ROS involvement on cardiac function and the mitochondrion following nano-TiO2 exposure. To address this question, we utilized a transgenic mouse model with overexpression of a novel mitochondrially-targeted antioxidant enzyme (phospholipid hydroperoxide glutathione peroxidase; mPHGPx) which provides protection against oxidative stress to lipid membranes. MPHGPx mice and littermate controls were exposed to nano-TiO2 aerosols (Evonik, P25) to provide a calculated pulmonary deposition of 11 µg/mouse. Twenty-four hours following exposure, we observed diastolic dysfunction as evidenced by E/A ratios greater than 2 and increased radial strain during diastole in wild-type mice (p < 0.05 for both), indicative of restrictive filling. Overexpression of mPHGPx mitigated the contractile deficits resulting from nano-TiO2 exposure. To investigate the cellular mechanisms associated with the observed cardiac dysfunction, we focused our attention on the mitochondrion. We observed a significant increase in ROS production (p < 0.05) and decreased mitochondrial respiratory function (p < 0.05) following nano-TiO2 exposure which were attenuated in mPHGPx transgenic mice. In summary, nano-TiO2 inhalation exposure is associated with cardiac diastolic dysfunction and mitochondrial functional alterations, which can be mitigated by the overexpression of mPHGPx, suggesting ROS contribution in the development of contractile and bioenergetic dysfunction.
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Affiliation(s)
- Cody E Nichols
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,b Immunity, Inflammation, and Disease Laboratory , National Institute of Environmental Health Sciences, Research Triangle Park , Durham , NC , USA
| | - Danielle L Shepherd
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,c Mitochondria, Metabolism and Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Quincy A Hathaway
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,c Mitochondria, Metabolism and Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Andrya J Durr
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,c Mitochondria, Metabolism and Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Dharendra Thapa
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Alaeddin Abukabda
- d Department of Physiology and Pharmacology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Jinghai Yi
- d Department of Physiology and Pharmacology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Timothy R Nurkiewicz
- c Mitochondria, Metabolism and Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA.,d Department of Physiology and Pharmacology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - John M Hollander
- a Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA.,c Mitochondria, Metabolism and Bioenergetics Working Group , West Virginia University School of Medicine , Morgantown , WV , USA
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Hathaway QA, Pinti MV, Durr AJ, Waris S, Shepherd DL, Hollander JM. Regulating microRNA expression: at the heart of diabetes mellitus and the mitochondrion. Am J Physiol Heart Circ Physiol 2017; 314:H293-H310. [PMID: 28986361 DOI: 10.1152/ajpheart.00520.2017] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Type 2 diabetes mellitus is a major risk factor for cardiovascular disease and mortality. Uncontrolled type 2 diabetes mellitus results in a systemic milieu of increased circulating glucose and fatty acids. The development of insulin resistance in cardiac tissue decreases cellular glucose import and enhances mitochondrial fatty acid uptake. While triacylglycerol and cytotoxic lipid species begin to accumulate in the cardiomyocyte, the energy substrate utilization ratio of free fatty acids to glucose changes to almost entirely free fatty acids. Accumulating evidence suggests a role of miRNA in mediating this metabolic transition. Energy substrate metabolism, apoptosis, and the production and response to excess reactive oxygen species are regulated by miRNA expression. The current momentum for understanding the dynamics of miRNA expression is limited by a lack of understanding of how miRNA expression is controlled. While miRNAs are important regulators in both normal and pathological states, an additional layer of complexity is added when regulation of miRNA regulators is considered. miRNA expression is known to be regulated through a number of mechanisms, which include, but are not limited to, epigenetics, exosomal transport, processing, and posttranscriptional sequestration. The purpose of this review is to outline how mitochondrial processes are regulated by miRNAs in the diabetic heart. Furthermore, we will highlight the regulatory mechanisms, such as epigenetics, exosomal transport, miRNA processing, and posttranslational sequestration, that participate as regulators of miRNA expression. Additionally, current and future treatment strategies targeting dysfunctional mitochondrial processes in the diseased myocardium, as well as emerging miRNA-based therapies, will be summarized.
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Affiliation(s)
- Quincy A Hathaway
- Division of Exercise Physiology, West Virginia University School of Medicine , Morgantown, West Virginia.,Mitochondria, Metabolism, and Bioenergetics Working Group, West Virginia University School of Medicine , Morgantown, West Virginia.,Toxicology Working Group, West Virginia University School of Medicine , Morgantown, West Virginia
| | - Mark V Pinti
- Division of Pharmaceutical and Pharmacological Sciences, West Virginia School of Pharmacy , Morgantown, West Virginia
| | - Andrya J Durr
- Division of Exercise Physiology, West Virginia University School of Medicine , Morgantown, West Virginia.,Mitochondria, Metabolism, and Bioenergetics Working Group, West Virginia University School of Medicine , Morgantown, West Virginia
| | - Shanawar Waris
- Department of Biomedical Engineering, West Virginia College of Engineering , Morgantown, West Virginia
| | - Danielle L Shepherd
- Division of Exercise Physiology, West Virginia University School of Medicine , Morgantown, West Virginia
| | - John M Hollander
- Division of Exercise Physiology, West Virginia University School of Medicine , Morgantown, West Virginia.,Mitochondria, Metabolism, and Bioenergetics Working Group, West Virginia University School of Medicine , Morgantown, West Virginia.,Toxicology Working Group, West Virginia University School of Medicine , Morgantown, West Virginia
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10
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Shepherd DL, Hathaway QA, Pinti MV, Nichols CE, Durr AJ, Sreekumar S, Hughes KM, Stine SM, Martinez I, Hollander JM. Exploring the mitochondrial microRNA import pathway through Polynucleotide Phosphorylase (PNPase). J Mol Cell Cardiol 2017; 110:15-25. [PMID: 28709769 DOI: 10.1016/j.yjmcc.2017.06.012] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 06/20/2017] [Accepted: 06/27/2017] [Indexed: 01/01/2023]
Abstract
Cardiovascular disease is the primary cause of mortality for individuals with type 2 diabetes mellitus. During the diabetic condition, cardiovascular dysfunction can be partially attributed to molecular changes in the tissue, including alterations in microRNA (miRNA) interactions. MiRNAs have been reported in the mitochondrion and their presence may influence cellular bioenergetics, creating decrements in functional capacity. In this study, we examined the roles of Argonaute 2 (Ago2), a protein associated with cytosolic and mitochondrial miRNAs, and Polynucleotide Phosphorylase (PNPase), a protein found in the inner membrane space of the mitochondrion, to determine their role in mitochondrial miRNA import. In cardiac tissue from human and mouse models of type 2 diabetes mellitus, Ago2 protein levels were unchanged while PNPase protein expression levels were increased; also, there was an increase in the association between both proteins in the diabetic state. MiRNA-378 was found to be significantly increased in db/db mice, leading to decrements in ATP6 levels and ATP synthase activity, which was also exhibited when overexpressing PNPase in HL-1 cardiomyocytes and in HL-1 cells with stable miRNA-378 overexpression (HL-1-378). To assess potential therapeutic interventions, flow cytometry evaluated the capacity for targeting miRNA-378 species in mitochondria through antimiR treatment, revealing miRNA-378 level-dependent inhibition. Our study establishes PNPase as a contributor to mitochondrial miRNA import through the transport of miRNA-378, which may regulate bioenergetics during type 2 diabetes mellitus. Further, our data provide evidence that manipulation of PNPase levels may enhance the delivery of antimiR therapeutics to mitochondria in physiological and pathological conditions.
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Affiliation(s)
- Danielle L Shepherd
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, United States; Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26506, United States
| | - Quincy A Hathaway
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, United States; Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26506, United States
| | - Mark V Pinti
- Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26506, United States
| | - Cody E Nichols
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, United States
| | - Andrya J Durr
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, United States; Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26506, United States
| | - Shruthi Sreekumar
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, United States
| | - Kristen M Hughes
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, United States
| | - Seth M Stine
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, United States
| | - Ivan Martinez
- Cancer Cell Biology, West Virginia University School of Medicine, Morgantown, WV 26506, United States
| | - John M Hollander
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, United States; Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, WV 26506, United States.
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11
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Corbin DR, Rehg JE, Shepherd DL, Stoilov P, Percifield RJ, Horner L, Frase S, Zhang YM, Rock CO, Hollander JM, Jackowski S, Leonardi R. Excess coenzyme A reduces skeletal muscle performance and strength in mice overexpressing human PANK2. Mol Genet Metab 2017; 120:350-362. [PMID: 28189602 PMCID: PMC5382100 DOI: 10.1016/j.ymgme.2017.02.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 02/01/2017] [Indexed: 11/23/2022]
Abstract
Coenzyme A (CoA) is a cofactor that is central to energy metabolism and CoA synthesis is controlled by the enzyme pantothenate kinase (PanK). A transgenic mouse strain expressing human PANK2 was derived to determine the physiological impact of PANK overexpression and elevated CoA levels. The Tg(PANK2) mice expressed high levels of the transgene in skeletal muscle and heart; however, CoA was substantially elevated only in skeletal muscle, possibly associated with the comparatively low endogenous levels of acetyl-CoA, a potent feedback inhibitor of PANK2. Tg(PANK2) mice were smaller, had less skeletal muscle mass and displayed significantly impaired exercise tolerance and grip strength. Skeletal myofibers were characterized by centralized nuclei and aberrant mitochondria. Both the content of fully assembled complex I of the electron transport chain and ATP levels were reduced, while markers of oxidative stress were elevated in Tg(PANK2) skeletal muscle. These abnormalities were not detected in the Tg(PANK2) heart muscle, with the exception of spotty loss of cristae organization in the mitochondria. The data demonstrate that excessively high CoA may be detrimental to skeletal muscle function.
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Affiliation(s)
- Deborah R Corbin
- Department of Biochemistry, West Virginia University, Morgantown, WV 26506, USA
| | - Jerold E Rehg
- Department Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Danielle L Shepherd
- Department of Exercise Physiology, West Virginia University, Morgantown, WV 26506, USA
| | - Peter Stoilov
- Department of Biochemistry, West Virginia University, Morgantown, WV 26506, USA
| | - Ryan J Percifield
- Department of Biology, West Virginia University, Morgantown, WV 26506, USA
| | - Linda Horner
- Cell and Tissue Imaging-Electron Microscopy Shared Resource, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Sharon Frase
- Cell and Tissue Imaging-Electron Microscopy Shared Resource, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Yong-Mei Zhang
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Charles O Rock
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - John M Hollander
- Department of Exercise Physiology, West Virginia University, Morgantown, WV 26506, USA
| | - Suzanne Jackowski
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Roberta Leonardi
- Department of Biochemistry, West Virginia University, Morgantown, WV 26506, USA.
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12
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Hathaway QA, Nichols CE, Shepherd DL, Stapleton PA, McLaughlin SL, Stricker JC, Rellick SL, Pinti MV, Abukabda AB, McBride CR, Yi J, Stine SM, Nurkiewicz TR, Hollander JM. Maternal-engineered nanomaterial exposure disrupts progeny cardiac function and bioenergetics. Am J Physiol Heart Circ Physiol 2016; 312:H446-H458. [PMID: 28011589 PMCID: PMC5402018 DOI: 10.1152/ajpheart.00634.2016] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 12/07/2016] [Accepted: 12/07/2016] [Indexed: 01/25/2023]
Abstract
Nanomaterial production is expanding as new industrial and consumer applications are introduced. Nevertheless, the impacts of exposure to these compounds are not fully realized. The present study was designed to determine whether gestational nano-sized titanium dioxide exposure impacts cardiac and metabolic function of developing progeny. Pregnant Sprague-Dawley rats were exposed to nano-aerosols (~10 mg/m3, 130- to 150-nm count median aerodynamic diameter) for 7-8 nonconsecutive days, beginning at gestational day 5-6 Physiological and bioenergetic effects on heart function and cardiomyocytes across three time points, fetal (gestational day 20), neonatal (4-10 days), and young adult (6-12 wk), were evaluated. Functional analysis utilizing echocardiography, speckle-tracking based strain, and cardiomyocyte contractility, coupled with mitochondrial energetics, revealed effects of nano-exposure. Maternal exposed progeny demonstrated a decrease in E- and A-wave velocities, with a 15% higher E-to-A ratio than controls. Myocytes isolated from exposed animals exhibited ~30% decrease in total contractility, departure velocity, and area of contraction. Bioenergetic analysis revealed a significant increase in proton leak across all ages, accompanied by decreases in metabolic function, including basal respiration, maximal respiration, and spare capacity. Finally, electron transport chain complex I and IV activities were negatively impacted in the exposed group, which may be linked to a metabolic shift. Molecular data suggest that an increase in fatty acid metabolism, uncoupling, and cellular stress proteins may be associated with functional deficits of the heart. In conclusion, gestational nano-exposure significantly impairs the functional capabilities of the heart through cardiomyocyte impairment, which is associated with mitochondrial dysfunction.NEW & NOTEWORTHY Cardiac function is evaluated, for the first time, in progeny following maternal nanomaterial inhalation. The findings indicate that exposure to nano-sized titanium dioxide (nano-TiO2) during gestation negatively impacts cardiac function and mitochondrial respiration and bioenergetics. We conclude that maternal nano-TiO2 inhalation contributes to adverse cardiovascular health effects, lasting into adulthood.
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Affiliation(s)
- Quincy A Hathaway
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia.,Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Cody E Nichols
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Danielle L Shepherd
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia.,Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Phoebe A Stapleton
- Department of Physiology and Pharmacology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Sarah L McLaughlin
- Department of Cancer Cell Biology, West Virginia University School of Medicine; Morgantown, West Virginia; and
| | - Janelle C Stricker
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Stephanie L Rellick
- Department of Physiology and Pharmacology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Mark V Pinti
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Alaeddin B Abukabda
- Department of Physiology and Pharmacology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Carroll R McBride
- Department of Physiology and Pharmacology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Jinghai Yi
- Department of Physiology and Pharmacology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Seth M Stine
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia.,Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Timothy R Nurkiewicz
- Department of Physiology and Pharmacology, West Virginia University School of Medicine, Morgantown, West Virginia.,Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia
| | - John M Hollander
- Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia; .,Mitochondria, Metabolism & Bioenergetics Working Group, West Virginia University School of Medicine, Morgantown, West Virginia
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13
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Shepherd DL, Nichols CE, Croston TL, McLaughlin SL, Petrone AB, Lewis SE, Thapa D, Long DM, Dick GM, Hollander JM. Early detection of cardiac dysfunction in the type 1 diabetic heart using speckle-tracking based strain imaging. J Mol Cell Cardiol 2015; 90:74-83. [PMID: 26654913 DOI: 10.1016/j.yjmcc.2015.12.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 11/11/2015] [Accepted: 12/02/2015] [Indexed: 12/14/2022]
Abstract
Enhanced sensitivity in echocardiographic analyses may allow for early detection of changes in cardiac function beyond the detection limits of conventional echocardiographic analyses, particularly in a small animal model. The goal of this study was to compare conventional echocardiographic measurements and speckle-tracking based strain imaging analyses in a small animal model of type 1 diabetes mellitus. Conventional analyses revealed differences in ejection fraction, fractional shortening, cardiac output, and stroke volume in diabetic animals relative to controls at 6-weeks post-diabetic onset. In contrast, when assessing short- and long-axis speckle-tracking based strain analyses, diabetic mice showed changes in average systolic radial strain, radial strain rate, radial displacement, and radial velocity, as well as decreased circumferential and longitudinal strain rate, as early as 1-week post-diabetic onset and persisting throughout the diabetic study. Further, we performed regional analyses for the LV and found that the free wall region was affected in both the short- and long-axis when assessing radial dimension parameters. These changes began 1-week post-diabetic onset and remained throughout the progression of the disease. These findings demonstrate the use of speckle-tracking based strain as an approach to elucidate cardiac dysfunction from a global perspective, identifying left ventricular cardiac regions affected during the progression of type 1 diabetes mellitus earlier than contractile changes detected by conventional echocardiographic measurements.
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Affiliation(s)
- Danielle L Shepherd
- Department of Exercise Physiology, Center for Cardiovascular and Respiratory Sciences, School of Medicine, West Virginia University, Morgantown, WV, 26505, United States
| | - Cody E Nichols
- Department of Exercise Physiology, Center for Cardiovascular and Respiratory Sciences, School of Medicine, West Virginia University, Morgantown, WV, 26505, United States
| | - Tara L Croston
- Department of Exercise Physiology, Center for Cardiovascular and Respiratory Sciences, School of Medicine, West Virginia University, Morgantown, WV, 26505, United States
| | - Sarah L McLaughlin
- Department of Cancer Cell Biology, School of Medicine, West Virginia University, Morgantown, WV 26505, United States
| | - Ashley B Petrone
- Department of Neurobiology and Anatomy, School of Medicine, West Virginia University, Morgantown, WV 26505, United States
| | - Sara E Lewis
- Department of Exercise Physiology, Center for Cardiovascular and Respiratory Sciences, School of Medicine, West Virginia University, Morgantown, WV, 26505, United States
| | - Dharendra Thapa
- Department of Exercise Physiology, Center for Cardiovascular and Respiratory Sciences, School of Medicine, West Virginia University, Morgantown, WV, 26505, United States
| | - Dustin M Long
- Department of Biostatistics, School of Public Health, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV 26505, United States
| | - Gregory M Dick
- Department of Exercise Physiology, Center for Cardiovascular and Respiratory Sciences, School of Medicine, West Virginia University, Morgantown, WV, 26505, United States
| | - John M Hollander
- Department of Exercise Physiology, Center for Cardiovascular and Respiratory Sciences, School of Medicine, West Virginia University, Morgantown, WV, 26505, United States.
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14
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Nichols CE, Shepherd DL, Knuckles TL, Thapa D, Stricker JC, Stapleton PA, Minarchick VC, Erdely A, Zeidler-Erdely PC, Alway SE, Nurkiewicz TR, Hollander JM. Cardiac and mitochondrial dysfunction following acute pulmonary exposure to mountaintop removal mining particulate matter. Am J Physiol Heart Circ Physiol 2015; 309:H2017-30. [PMID: 26497962 DOI: 10.1152/ajpheart.00353.2015] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 10/05/2015] [Indexed: 01/29/2023]
Abstract
Throughout the United States, air pollution correlates with adverse health outcomes, and cardiovascular disease incidence is commonly increased following environmental exposure. In areas surrounding active mountaintop removal mines (MTM), a further increase in cardiovascular morbidity is observed and may be attributed in part to particulate matter (PM) released from the mine. The mitochondrion has been shown to be central in the etiology of many cardiovascular diseases, yet its roles in PM-related cardiovascular effects are not realized. In this study, we sought to elucidate the cardiac processes that are disrupted following exposure to mountaintop removal mining particulate matter (PM MTM). To address this question, we exposed male Sprague-Dawley rats to PM MTM, collected within one mile of an active MTM site, using intratracheal instillation. Twenty-four hours following exposure, we evaluated cardiac function, apoptotic indices, and mitochondrial function. PM MTM exposure elicited a significant decrease in ejection fraction and fractional shortening compared with controls. Investigation into the cellular impacts of PM MTM exposure identified a significant increase in mitochondrial-induced apoptotic signaling, as reflected by an increase in TUNEL-positive nuclei and increased caspase-3 and -9 activities. Finally, a significant increase in mitochondrial transition pore opening leading to decreased mitochondrial function was identified following exposure. In conclusion, our data suggest that pulmonary exposure to PM MTM increases cardiac mitochondrial-associated apoptotic signaling and decreases mitochondrial function concomitant with decreased cardiac function. These results suggest that increased cardiovascular disease incidence in populations surrounding MTM mines may be associated with increased cardiac cell apoptotic signaling and decreased mitochondrial function.
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Affiliation(s)
- Cody E Nichols
- West Virginia University School of Medicine, Division of Exercise Physiology, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia
| | - Danielle L Shepherd
- West Virginia University School of Medicine, Division of Exercise Physiology, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia
| | - Travis L Knuckles
- Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia; West Virginia University, School of Public Health, Morgantown, West Virginia
| | - Dharendra Thapa
- West Virginia University School of Medicine, Division of Exercise Physiology, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia
| | - Janelle C Stricker
- Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia
| | - Phoebe A Stapleton
- Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia; West Virginia University, Department of Physiology and Pharmacology, Morgantown, West Virginia
| | - Valerie C Minarchick
- Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia; West Virginia University, Department of Physiology and Pharmacology, Morgantown, West Virginia
| | - Aaron Erdely
- West Virginia University, Department of Physiology and Pharmacology, Morgantown, West Virginia; National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Patti C Zeidler-Erdely
- West Virginia University, Department of Physiology and Pharmacology, Morgantown, West Virginia; National Institute for Occupational Safety and Health, Morgantown, West Virginia
| | - Stephen E Alway
- West Virginia University School of Medicine, Division of Exercise Physiology, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia
| | - Timothy R Nurkiewicz
- Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia; West Virginia University, Department of Physiology and Pharmacology, Morgantown, West Virginia
| | - John M Hollander
- West Virginia University School of Medicine, Division of Exercise Physiology, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, Morgantown, West Virginia;
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15
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Jagannathan R, Thapa D, Nichols CE, Shepherd DL, Stricker JC, Croston TL, Baseler WA, Lewis SE, Martinez I, Hollander JM. Translational Regulation of the Mitochondrial Genome Following Redistribution of Mitochondrial MicroRNA in the Diabetic Heart. ACTA ACUST UNITED AC 2015; 8:785-802. [PMID: 26377859 DOI: 10.1161/circgenetics.115.001067] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 09/01/2015] [Indexed: 01/05/2023]
Abstract
BACKGROUND Cardiomyocytes are rich in mitochondria which are situated in spatially distinct subcellular regions, including those under the plasma membrane, subsarcolemmal mitochondria, and those between the myofibrils, interfibrillar mitochondria. We previously observed subpopulation-specific differences in mitochondrial proteomes following diabetic insult. The objective of this study was to determine whether mitochondrial genome-encoded proteins are regulated by microRNAs inside the mitochondrion and whether subcellular spatial location or diabetes mellitus influences the dynamics. METHODS AND RESULTS Using microarray technology coupled with cross-linking immunoprecipitation and next generation sequencing, we identified a pool of mitochondrial microRNAs, termed mitomiRs, that are redistributed in spatially distinct mitochondrial subpopulations in an inverse manner following diabetic insult. Redistributed mitomiRs displayed distinct interactions with the mitochondrial genome requiring specific stoichiometric associations with RNA-induced silencing complex constituents argonaute-2 (Ago2) and fragile X mental retardation-related protein 1 (FXR1) for translational regulation. In the presence of Ago2 and FXR1, redistribution of mitomiR-378 to the interfibrillar mitochondria following diabetic insult led to downregulation of mitochondrially encoded F0 component ATP6. Next generation sequencing analyses identified specific transcriptome and mitomiR sequences associated with ATP6 regulation. Overexpression of mitomiR-378 in HL-1 cells resulted in its accumulation in the mitochondrion and downregulation of functional ATP6 protein, whereas antagomir blockade restored functional ATP6 protein and cardiac pump function. CONCLUSIONS We propose mitomiRs can translationally regulate mitochondrially encoded proteins in spatially distinct mitochondrial subpopulations during diabetes mellitus. The results reveal the requirement of RNA-induced silencing complex constituents in the mitochondrion for functional mitomiR translational regulation and provide a connecting link between diabetic insult and ATP synthase function.
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Affiliation(s)
- Rajaganapathi Jagannathan
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown
| | - Dharendra Thapa
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown
| | - Cody E Nichols
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown
| | - Danielle L Shepherd
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown
| | - Janelle C Stricker
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown
| | - Tara L Croston
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown
| | - Walter A Baseler
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown
| | - Sara E Lewis
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown
| | - Ivan Martinez
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown
| | - John M Hollander
- From the Department of Human Performances, Division of Exercise Physiology (R.J., D.T., C.E.N., D.L.S., J.C.S., T.L.C., W.A.B., S.E.L., J.M.H.), Center for Cardiovascular and Respiratory Sciences (R.J., D.T., C.E.N., D.L.S., T.L.C., W.A.B., S.E.L., J.M.H.), Department of Microbiology, Immunology and Cell Biology (I.M.), and Mary Babb Randolph Cancer Center (I.M.), West Virginia University School of Medicine, Morgantown.
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16
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Stapleton PA, Nichols CE, Yi J, McBride CR, Minarchick VC, Shepherd DL, Hollander JM, Nurkiewicz TR. Microvascular and mitochondrial dysfunction in the female F1 generation after gestational TiO2 nanoparticle exposure. Nanotoxicology 2015; 9:941-51. [PMID: 25475392 DOI: 10.3109/17435390.2014.984251] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Due to the ongoing evolution of nanotechnology, there is a growing need to assess the toxicological outcomes in under-studied populations in order to properly consider the potential of engineered nanomaterials (ENM) and fully enhance their safety. Recently, we and others have explored the vascular consequences associated with gestational nanomaterial exposure, reporting microvascular dysfunction within the uterine circulation of pregnant dams and the tail artery of fetal pups. It has been proposed (via work derived by the Barker Hypothesis) that mitochondrial dysfunction and subsequent oxidative stress mechanisms as a possible link between a hostile gestational environment and adult disease. Therefore, in this study, we exposed pregnant Sprague-Dawley rats to nanosized titanium dioxide aerosols after implantation (gestational day 6). Pups were delivered, and the progeny grew into adulthood. Microvascular reactivity, mitochondrial respiration and hydrogen peroxide production of the coronary and uterine circulations of the female offspring were evaluated. While there were no significant differences within the maternal or litter characteristics, endothelium-dependent dilation and active mechanotransduction in both coronary and uterine arterioles were significantly impaired. In addition, there was a significant reduction in maximal mitochondrial respiration (state 3) in the left ventricle and uterus. These studies demonstrate microvascular dysfunction and coincide with mitochondrial inefficiencies in both the cardiac and uterine tissues, which may represent initial evidence that prenatal ENM exposure produces microvascular impairments that persist throughout multiple developmental stages.
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Affiliation(s)
- Phoebe A Stapleton
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
| | - Cody E Nichols
- a Center for Cardiovascular and Respiratory Sciences .,c Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Jinghai Yi
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
| | - Carroll R McBride
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
| | - Valerie C Minarchick
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
| | - Danielle L Shepherd
- a Center for Cardiovascular and Respiratory Sciences .,c Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - John M Hollander
- a Center for Cardiovascular and Respiratory Sciences .,c Division of Exercise Physiology , West Virginia University School of Medicine , Morgantown , WV , USA
| | - Timothy R Nurkiewicz
- a Center for Cardiovascular and Respiratory Sciences .,b Department of Physiology and Pharmacology , and
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Hollander JM, Thapa D, Shepherd DL. Physiological and structural differences in spatially distinct subpopulations of cardiac mitochondria: influence of cardiac pathologies. Am J Physiol Heart Circ Physiol 2014; 307:H1-14. [PMID: 24778166 DOI: 10.1152/ajpheart.00747.2013] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Cardiac tissue contains discrete pools of mitochondria that are characterized by their subcellular spatial arrangement. Subsarcolemmal mitochondria (SSM) exist below the cell membrane, interfibrillar mitochondria (IFM) reside in rows between the myofibrils, and perinuclear mitochondria are situated at the nuclear poles. Microstructural imaging of heart tissue coupled with the development of differential isolation techniques designed to sequentially separate spatially distinct mitochondrial subpopulations have revealed differences in morphological features including shape, absolute size, and internal cristae arrangement. These findings have been complemented by functional studies indicating differences in biochemical parameters and, potentially, functional roles for the ATP generated, based upon subcellular location. Consequently, mitochondrial subpopulations appear to be influenced differently during cardiac pathologies including ischemia/reperfusion, heart failure, aging, exercise, and diabetes mellitus. These influences may be the result of specific structural and functional disparities between mitochondrial subpopulations such that the stress elicited by a given cardiac insult differentially impacts subcellular locales and the mitochondria contained within. The goal of this review is to highlight some of the inherent structural and functional differences that exist between spatially distinct cardiac mitochondrial subpopulations as well as provide an overview of the differential impact of various cardiac pathologies on spatially distinct mitochondrial subpopulations. As an outcome, we will instill a basis for incorporating subcellular spatial location when evaluating the impact of cardiac pathologies on the mitochondrion. Incorporation of subcellular spatial location may offer the greatest potential for delineating the influence of cardiac pathology on this critical organelle.
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Croston TL, Thapa D, Holden AA, Tveter KJ, Lewis SE, Shepherd DL, Nichols CE, Long DM, Olfert IM, Jagannathan R, Hollander JM. Functional deficiencies of subsarcolemmal mitochondria in the type 2 diabetic human heart. Am J Physiol Heart Circ Physiol 2014; 307:H54-65. [PMID: 24778174 DOI: 10.1152/ajpheart.00845.2013] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The mitochondrion has been implicated in the development of diabetic cardiomyopathy. Examination of cardiac mitochondria is complicated by the existence of spatially distinct subpopulations including subsarcolemmal (SSM) and interfibrillar (IFM). Dysfunction to cardiac SSM has been reported in murine models of type 2 diabetes mellitus; however, subpopulation-based mitochondrial analyses have not been explored in type 2 diabetic human heart. The goal of this study was to determine the impact of type 2 diabetes mellitus on cardiac mitochondrial function in the human patient. Mitochondrial subpopulations from atrial appendages of patients with and without type 2 diabetes were examined. Complex I- and fatty acid-mediated mitochondrial respiration rates were decreased in diabetic SSM compared with nondiabetic (P ≤ 0.05 for both), with no change in IFM. Electron transport chain (ETC) complexes I and IV activities were decreased in diabetic SSM compared with nondiabetic (P ≤ 0.05 for both), with a concomitant decline in their levels (P ≤ 0.05 for both). Regression analyses comparing comorbidities determined that diabetes mellitus was the primary factor accounting for mitochondrial dysfunction. Linear spline models examining correlative risk for mitochondrial dysfunction indicated that patients with diabetes display the same degree of state 3 and electron transport chain complex I dysfunction in SSM regardless of the extent of glycated hemoglobin (HbA1c) and hyperglycemia. Overall, the results suggest that independent of other pathologies, mitochondrial dysfunction is present in cardiac SSM of patients with type 2 diabetes and the degree of dysfunction is consistent regardless of the extent of elevated HbA1c or blood glucose levels.
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Affiliation(s)
- Tara L Croston
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Dharendra Thapa
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Anthony A Holden
- West Virginia University School of Medicine, Department of Surgery, Morgantown, West Virginia
| | - Kevin J Tveter
- West Virginia University School of Medicine, Department of Surgery, Morgantown, West Virginia
| | - Sara E Lewis
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Danielle L Shepherd
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Cody E Nichols
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Dustin M Long
- West Virginia University School of Public Health, Department of Biostatistics, Morgantown, West Virginia
| | - I Mark Olfert
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Rajaganapathi Jagannathan
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia
| | - John M Hollander
- Division of Exercise Physiology and Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia;
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19
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Croston TL, Shepherd DL, Thapa D, Nichols CE, Lewis SE, Dabkowski ER, Jagannathan R, Baseler WA, Hollander JM. Evaluation of the cardiolipin biosynthetic pathway and its interactions in the diabetic heart. Life Sci 2013; 93:313-22. [PMID: 23872101 DOI: 10.1016/j.lfs.2013.07.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 06/26/2013] [Accepted: 07/01/2013] [Indexed: 11/28/2022]
Abstract
AIMS We have previously reported alterations in cardiolipin content and inner mitochondrial membrane (IMM) proteomic make-up specifically in interfibrillar mitochondria (IFM) in the type 1 diabetic heart; however, the mechanism underlying this alteration is unknown. The goal of this study was to determine how the cardiolipin biosynthetic pathway and cardiolipin-IMM protein interactions are impacted by type 1 diabetes mellitus. MAIN METHODS Male FVB mice were made diabetic by multiple low-dose streptozotocin injections and sacrificed five weeks post-diabetic onset. Messenger RNA was measured and cardiac mitochondrial subpopulations were isolated. Further mitochondrial functional experimentation included evaluating the protein expression of the enzymes directly responsible for cardiolipin biosynthesis, as well as ATP synthase activity. Interactions between cardiolipin and ATP synthase subunits were also examined. KEY FINDINGS Western blot analysis revealed a significant decrease in cardiolipin synthase (CRLS) protein content in diabetic IFM, with a concomitant decrease in its activity. ATP synthase activity was also significantly decreased. We identified two novel direct interactions between two subunits of the ATP synthase F0 complex (ATP5F1 and ATP5H), both of which were significantly decreased in diabetic IFM. SIGNIFICANCE Overall, these results indicate that type 1 diabetes mellitus negatively impacts the cardiolipin biosynthetic pathway specifically at CRLS, contributing to decreased cardiolipin content and loss of interactions with key ATP synthase F0 complex constituents in the IFM.
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Affiliation(s)
- Tara L Croston
- West Virginia University School of Medicine, Division of Exercise Physiology, Center for Cardiovascular and Respiratory Sciences, Morgantown, WV 26506, USA
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Jagannathan R, Thapa D, Baseler WA, Shepherd DL, Croston TL, Nichols CE, Lewis SE, Hollander JM. Translational regulation of the mitochondrial genome following redistribution of mitochondrial microRNA (MitomiR) in the diabetic heart. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.701.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Dharendra Thapa
- Division of Exercise PhysiologyWest Virginia UniversityMorgantownWV
| | - Walter A Baseler
- Division of Exercise PhysiologyWest Virginia UniversityMorgantownWV
| | | | - Tara L Croston
- Division of Exercise PhysiologyWest Virginia UniversityMorgantownWV
| | - Cody E Nichols
- Division of Exercise PhysiologyWest Virginia UniversityMorgantownWV
| | - Sara E Lewis
- Division of Exercise PhysiologyWest Virginia UniversityMorgantownWV
| | - John M Hollander
- Division of Exercise PhysiologyWest Virginia UniversityMorgantownWV
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21
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Thapa D, Jagannathan R, Croston TL, Baseler WA, Nichols CE, Shepherd DL, Lewis SE, Hollander JM. Interaction of mitofilin with respiratory complexes in mitochondrial subpopulations. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.1126.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | | | | | | | - Sara E Lewis
- Exercise PhysiologyWest Virginia UniversityMorgantownWV
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22
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Lewis SE, Dabkowski ER, Baseler WA, Shepherd DL, Croston TL, Nichols CE, Hollander JM. Impact of mitochondria phospholipid hydroperoxide glutathione peroxidase (mPHGPx) overexpression on the type 1 diabetic heart. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.1209.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Sara E Lewis
- Exercise physiologyWest Virginia UniversityMorgantownWV
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23
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Croston TL, Holden AA, Tveter K, Lewis SE, Thapa D, Shepherd DL, Nichols CE, Jagannathan R, Hollander JM. Diabetic mouse hearts: a good predictor for the human population? FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.701.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Kevin Tveter
- Department of SurgeryWest Virginia UnversityMorgantownWV
| | - Sara E. Lewis
- Exercise PhysiologyWest Virginia UnversityMorgantownWV
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Baseler WA, Dabkowski ER, Jagannathan R, Thapa D, Nichols CE, Shepherd DL, Croston TL, Powell M, Razunguzwa TT, Lewis SE, Schnell DM, Hollander JM. Reversal of mitochondrial proteomic loss in Type 1 diabetic heart with overexpression of phospholipid hydroperoxide glutathione peroxidase. Am J Physiol Regul Integr Comp Physiol 2013; 304:R553-65. [PMID: 23408027 DOI: 10.1152/ajpregu.00249.2012] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mitochondrial dysfunction is a contributor to diabetic cardiomyopathy. Previously, we observed proteomic decrements within the inner mitochondrial membrane (IMM) and matrix of diabetic cardiac interfibrillar mitochondria (IFM) correlating with dysfunctional mitochondrial protein import. The goal of this study was to determine whether overexpression of mitochondria phospholipid hydroperoxide glutathione peroxidase 4 (mPHGPx), an antioxidant enzyme capable of scavenging membrane-associated lipid peroxides in the IMM, could reverse proteomic alterations, dysfunctional protein import, and ultimately, mitochondrial dysfunction associated with the diabetic heart. MPHGPx transgenic mice and controls were made diabetic by multiple low-dose streptozotocin injections and examined after 5 wk of hyperglycemia. Five weeks after hyperglycemia onset, in vivo analysis of cardiac contractile function revealed decreased ejection fraction and fractional shortening in diabetic hearts that was reversed with mPHGPx overexpression. MPHGPx overexpression increased electron transport chain function while attenuating hydrogen peroxide production and lipid peroxidation in diabetic mPHGPx IFM. MPHGPx overexpression lessened proteomic loss observed in diabetic IFM. Posttranslational modifications, including oxidations and deamidations, were attenuated in diabetic IFM with mPHGPx overexpression. Mitochondrial protein import dysfunction in diabetic IFM was reversed with mPHGPx overexpression correlating with protein import constituent preservation. Ingenuity Pathway Analyses indicated that oxidative phosphorylation, tricarboxylic acid cycle, and fatty acid oxidation processes most influenced in diabetic IFM were preserved by mPHGPx overexpression. Specific mitochondrial networks preserved included complex I and II, mitochondrial ultrastructure, and mitochondrial protein import. These results indicate that mPHGPx overexpression can preserve the mitochondrial proteome and provide cardioprotective benefits to the diabetic heart.
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Affiliation(s)
- Walter A Baseler
- Center for Cardiovascular and Respiratory Sciences, Division of Exercise Physiology, West Virginia University School of Medicine, Morgantown, WV 26506, USA
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25
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Nichols CE, Baseler WA, Thapa D, LaFata G, Croston TL, Shepherd DL, Lewis SE, Knuckles TL, McCawley M, Hendryx M, Nurkiewicz TR, Hollander JM. Mountain‐top mining particulate matter exposure increases markers of mitochondrially‐driven apoptosis in rat cardiac tissue. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.1036.15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Cody Edward Nichols
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Walter A. Baseler
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Dharendra Thapa
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Gabrielle LaFata
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Tara L. Croston
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Danielle L. Shepherd
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Sara E. Lewis
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Travis L. Knuckles
- Department of Physiology and PharmacolgyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | | | | | - Timothy R. Nurkiewicz
- Department of Physiology and PharmacolgyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - John M. Hollander
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
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26
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Jagannathan R, Baseler WA, Thapa D, Croston TL, Shepherd DL, Nichols CE, Hollander JM. HDAC6 regulates mitochondrial oxidative phosphorylation by ATP synthase beta subunit acetylation in diabetic cardiomyopathy. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.869.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Rajaganapathi Jagannathan
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Walter A Baseler
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Dharendra Thapa
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Tara L Croston
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Danielle L Shepherd
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Cody E Nichols
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - John M Hollander
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
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27
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Croston TL, Shepherd DL, Baseler WA, Dabkowski ER, Thapa D, Nichols CE, Jagannathan R, Lewis SE, Hollander JM. Examination of cardiolipin biosynthesis in the diabetic heart. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.lb746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | | | | | | | | | - Sara E Lewis
- Exercise PhysiologyWest Virginia UniversityMorgantownWV
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28
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Baseler WA, Dabkowski ER, Jagannathan R, Thapa D, Nichols CE, Shepherd DL, Croston TL, Schnell DM, Hollander JM. Overexpression of phospholipid hydroperoxide glutathione peroxidase (MPHGPx) attenuates cardiac mitochondrial proteomic loss and reverses protein import detriments observed with type 1 diabetes mellitus. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.1127.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Walter A. Baseler
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Erinne R. Dabkowski
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Rajaganapathi Jagannathan
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Dharendra Thapa
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Cody E. Nichols
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Danielle L. Shepherd
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Tara L. Croston
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - David M. Schnell
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - John M. Hollander
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
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29
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Thapa D, Baseler WA, Jagannathan R, Dabkowski ER, Croston TL, Nichols CE, Shepherd DL, Lewis SE, Hollander JM. miRNA‐141 is a potential regulator of the mitochondrial phosphate carrier (slc25a3) in the type 1 diabetic heart. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.869.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Dharendra Thapa
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Walter A Baseler
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Rajaganapathi Jagannathan
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Erinne R Dabkowski
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Tara L Croston
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Cody E Nichols
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Danielle L Shepherd
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - Sara E Lewis
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
| | - John M Hollander
- Division of Exercise PhysiologyCenter for Cardiovascular and Respiratory SciencesWest Virginia UniversityMorgantownWV
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30
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Matsunaga GS, Shepherd DL, Troyer DA, Thompson IM. Epididymal rhabdomyoma. J Urol 2000; 163:1876. [PMID: 10799212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Affiliation(s)
- G S Matsunaga
- Divisions of Pathology and Urology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
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31
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Arcangeli CG, Humphrey PA, Smith DS, Harmon TJ, Shepherd DL, Keetch DW, Catalona WJ. Percentage of free serum prostate-specific antigen as a predictor of pathologic features of prostate cancer in a screening population. Urology 1998; 51:558-64; discussion 564-5. [PMID: 9586607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES Measurement of the percentage of free prostate-specific antigen (%FPSA) in serum can improve the specificity of prostate cancer screening. We evaluated the ability of %FPSA to predict pathologic features of screen-detected clinically localized prostate cancer. METHODS We evaluated the correlation between %FPSA in serum before cancer diagnosis and the pathologic features of the cancers detected in 108 men with clinically localized prostate cancer who were treated with radical prostatectomy and for whom complete embedding of the radical prostatectomy specimen was performed. Ninety-seven men (90%) had a previous negative screening evaluation before prostate cancer was detected. RESULTS There was a negative correlation of %FPSA with penetration of cancer through the prostatic capsule, cancerous surgical margins, Gleason score, percentage of cancer in the gland, and tumor volume (r = -0.2 to -0.4). After controlling for other preoperative predictors, %FPSA predicted capsular penetration (adjusted odds ratio [OR] 1.6, 95% confidence interval [CI] 1.1 to 2.4, for each 5% decrease in %FPSA) and cancer volume 0.5 cc or greater (adjusted OR 1.6, 95% CI 1.1 to 2.3). Preoperative %FPSA also predicted possibly harmless cancer (OR 1.5, 95% CI 1.1 to 2.2, for each 5% increase in %FPSA). CONCLUSIONS In a select group of men for whom cancer was detected early via screening, a lower %FPSA in serum suggests a potentially more threatening cancer. This information may aid patients and clinicians in making more informed decisions about the management of prostate cancer, such as selecting patients for watchful waiting. However, more research is needed to determine the performance characteristics of %FPSA in clinical practice.
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Affiliation(s)
- C G Arcangeli
- Department of Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
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Abstract
The nucleolar and mitochondrial morphology of developing reconstructed bovine nuclear transfer (NT) embryos and stage-matched in vivo-produced control embryos were examined under the electron microscope. Each reconstructed embryo at the one-cell (n = 12), two-cell (n = 5), three-cell (n = 3), four-cell (n = 5), 5-8-cell (n = 5) and blastocyst (n = 3) stages was produced by fusion of a 16-32-cell-stage blatomere with an aged enucleated bovine oocyte. The normal and reconstructed embryos showed similar mitochondrial morphology. However, NT embryos produced several pleiomorphic forms not seen in controls, and were more heterogeneous at early stages of development. Control embryos exhibited nucleolar features considered indicative of rRNA synthesis from the eight-cell stage onwards. In contrast, the NT embryos presented nucleoli with morphology consistent with rRNA synthesis in all embryos examined, except in the three-cell and in two of the five four-cell embryos. From this nucleolar morphology, it was concluded that nuclear reprogramming does not occur immediately following nuclear transfer, but occurs gradually over the first two or three cell cycles.
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Affiliation(s)
- W A King
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Canada
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Wolf JS, Clayman RV, McDougall EM, Shepherd DL, Folger WH, Monk TG. Carbon dioxide and helium insufflation during laparoscopic radical nephrectomy in a patient with severe pulmonary disease. J Urol 1996; 155:2021. [PMID: 8618313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- J S Wolf
- Division of Urologic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
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Humphrey PA, Keetch DW, Smith DS, Shepherd DL, Catalona WJ. Prospective characterization of pathological features of prostatic carcinomas detected via serum prostate specific antigen based screening. J Urol 1996; 155:816-20. [PMID: 8583583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
PURPOSE Many small (less than 0.5 cc), well differentiated, organ-confined prostate carcinomas remain clinically undetected during the life of the patient and are identified only at postmortem examination. Thus, these cancers are often called latent or autopsy cancers. There is concern that serum prostate specific antigen (PSA) based screening may preferentially detect these cancers. There are limited prospective data concerning the pathological features of carcinomas of the prostate detected in a screening program. We determined if prostatic carcinomas detected via PSA based screening resembled autopsy cancers. MATERIALS AND METHODS We assessed the pathological features of carcinomas in 100 consecutive, completely embedded radical prostatectomy specimens from men whose cancer was detected in a PSA based screening program. The tumors were evaluated for pathological stage, surgical margin status, Gleason histological grade and intraglandular tumor extent (morphometrically quantified as percentage carcinoma and tumor volume). RESULTS Of 100 carcinomas 68 (68%) were larger than 0.5 cc in volume (mean 1.7, range 0.1 to 10.7). Mean amount of carcinoma in the surgical specimen was 10.3% (range 0.1 to 41.6). Of the 100 carcinomas 94 had a Gleason score of 5 to 8 (mean 5.7) and only 6 (6%) were well differentiated (Gleason score of 4 or less). Locally advanced disease was noted in 41 cases (41%) as judged by the presence of extracapsular carcinoma and/or cancerous surgical margins. CONCLUSIONS We concluded that the pathological features of most prostatic carcinomas detected via PSA based screening do not resemble those of autopsy cancers, and that most prostatic cancers detected in screening programs are likely to be clinically important.
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Affiliation(s)
- P A Humphrey
- Department of Pathology (Lauren V. Ackerman Surgical Pathology Laboratory), Washington University Medical Center, St. Louis, Missouri,USA
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35
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Abstract
The timing of genome activation in bovine embryos is still not well defined. The objective of this study was therefore to investigate transcription in bovine embryos with a high potential to develop in culture after in vitro fertilization, by examining, autoradiographically, their incorporation of 3H-uridine. Initial experiments determined that developmental potential in vitro could be related to the time of first division of the zygote. Embryos that completed their first cleavage within 30 hours of exposure to sperm were more likely to develop into blastocysts (65.7%) and to hatch (50.9%). Using such embryos, it was found that 10 of 12 8-cell and all 11 4-cell stage embryos were labeled after a 2-4-hr exposure to 3H-Uridine. Among 2-cell stage embryos, 0 of 23, 3 of 17, 8 of 15, and 3 of 4 were labeled after exposure to 3H-uridine of 2, 4, 7, and 10 hr, respectively. Treatment with alpha-amanatin (10-100 micrograms/ml) blocked 3H-uridine incorporation but did not inhibit cleavage during the first 4 cell cycles. It was concluded that transcription occurs as early as the 2-cell stage in bovine embryos in vitro but is not critical to the first four cell cycles.
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Affiliation(s)
- L Plante
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Canada
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