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Jarrett SG, Wolf Horrell EM, Christian PA, Vanover JC, Boulanger MC, Zou Y, D’Orazio JA. Retraction Notice to: PKA-Mediated Phosphorylation of ATR Promotes Recruitment of XPA to UV-Induced DNA Damage. Mol Cell 2022; 82:4400. [PMID: 36400011 PMCID: PMC9721266 DOI: 10.1016/j.molcel.2022.10.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Harrison NJ, Ford MM, Wolf Horrell EM, Feng M, Ye F, Zhang KC, Hawkins AT. Long-term bowel dysfunction and decision regret in diverticulitis: A mixed methods study. Surgery 2022; 172:1194-1201. [PMID: 35927081 DOI: 10.1016/j.surg.2022.04.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 03/27/2022] [Accepted: 04/29/2022] [Indexed: 11/25/2022]
Abstract
BACKGROUND This study had aimed to describe long-term decision regret, bowel dysfunction, and the overall quality of life in patients with diverticulitis, and to determine if elective colectomy was associated with these patient-reported outcome measures. METHODS This mixed-methods, survey-based study was administered to a national cohort of patients in the United States with diverticulitis. We measured decision regret (Brehaut Decision Regret), bowel dysfunction (Low Anterior Resection Syndrome score), and the overall quality of life (EuroQol 5 Dimension) in this population. We asked open-ended questions to elucidate factors that influenced patients' choices between elective colectomy and observation. RESULTS Among the 614 respondents, 294 (48%) chose between colectomy and observational management, 94 (15%) had surgery, and 157 (26%) had major Low Anterior Resection Syndrome. Of the 294 that chose between colectomy and observational management, 51 (17%) experienced decision regret. Colectomy was associated with an average decrease in the Brehaut Decision Regret score by 6 points but was not associated with a categorical measure of decision regret (Brehaut Score ≥50). Bowel dysfunction and overall quality of life were not significantly associated with colectomy. Disease-related factors, psychosocial factors, and interactions with physicians were commonly cited as reasons for pursuing colectomy or observational management. CONCLUSION Patients with self-reported diverticulitis describe high levels of decision regret and bowel dysfunction regardless of chosen management strategy. Physicians should be aware that psychosocial factors can strongly influence a patient's choice between colectomy and observational management. We advocated for future prospective studies using patient reported outcome metrics to improve outcomes in diverticulitis.
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Affiliation(s)
- Noah J Harrison
- School of Medicine, Vanderbilt University, Nashville, TN. https://twitter.com/alexhawkinsmd
| | - Molly M Ford
- Vanderbilt University Medical Center, Division of General Surgery, Section of Colon & Rectal Surgery, Nashville, TN
| | - Erin M Wolf Horrell
- Vanderbilt University Medical Center, Division of General Surgery, Section of Colon & Rectal Surgery, Nashville, TN
| | - Michael Feng
- Vanderbilt University Medical Center, Division of General Surgery, Section of Colon & Rectal Surgery, Nashville, TN
| | - Fei Ye
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
| | - Kevin C Zhang
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
| | - Alexander T Hawkins
- Vanderbilt University Medical Center, Division of General Surgery, Section of Colon & Rectal Surgery, Nashville, TN.
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Fletcher KT, Horrell EMW, Ayugi J, Irungu C, Muthoka M, Creel LM, Lester C, Bush ML. The Natural History and Rehabilitative Outcomes of Hearing Loss in Congenital Cytomegalovirus: A Systematic Review. Otol Neurotol 2019; 39:854-864. [PMID: 29912824 DOI: 10.1097/mao.0000000000001861] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The purpose of this study was to examine the literature regarding the natural history and rehabilitative outcomes of sensorineural hearing loss from congenital cytomegalovirus infections. DATA SOURCES AND STUDY ELIGIBILITY CRITERIA A systematic search was performed in PubMed, PsychINFO, CINAHL, and Web of Science to identify peer-reviewed research. Eligible studies were those containing original peer-reviewed research in English addressing either the natural history or rehabilitative outcomes of sensorineural hearing loss (SNHL) in congenital cytomegalovirus (cCMV). STUDY APPRAISAL AND SYNTHESIS METHODS Two investigators independently reviewed all articles and extracted data. Bias was assessed using the Cochrane Collaboration's tool and the Newcastle-Ottawa Assessment Scale. RESULTS Thirty-six articles were reviewed. Universal screening identifies 0.2 to 1% of newborns with cCMV infection. SNHL ranged from 8 to 32% of infants and was more prevalent in symptomatic versus asymptomatic cases. Nine to 68% of hearing loss occurs in a late or delayed fashion. In 7 to 71% of cases hearing loss is progressive. Cochlear implantation (CI) is a viable option for patients with cCMV associated hearing loss and leads to improvements in hearing and language. There is limited literature comparing rehabilitation outcomes in cCMV and non-cCMV CI recipients. CONCLUSION Late onset and progressive hearing loss is seen in children who develop hearing loss from cCMV. Frequent audiologic follow-up is necessary considering the natural history of cCMV hearing loss. Universal screening should be pursued due to the number of asymptomatic children, at birth, who develop late onset/delayed hearing loss. CI is an effective means of improving speech and language in this population.
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Affiliation(s)
- Kyle T Fletcher
- Department of Otolaryngology-Head and Neck Surgery, University of Kentucky Medical Center
| | | | - John Ayugi
- Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Nairobi College of Health Sciences, Nairobi, Kenya
| | - Catherine Irungu
- Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Nairobi College of Health Sciences, Nairobi, Kenya
| | - Maria Muthoka
- Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Nairobi College of Health Sciences, Nairobi, Kenya
| | - Liza M Creel
- Department of Health Management and Systems Sciences, University of Louisville School of Public Health and Information Sciences
| | - Cathy Lester
- Cabinet for Health and Family Services Commission for Children with Special Health Care Needs, Louisville, Kentucky
| | - Matthew L Bush
- Department of Otolaryngology-Head and Neck Surgery, University of Kentucky Medical Center
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Wolf Horrell EM, Jarrett SG, Carter KM, D'Orazio JA. Divergence of cAMP signalling pathways mediating augmented nucleotide excision repair and pigment induction in melanocytes. Exp Dermatol 2017; 26:577-584. [PMID: 28094871 DOI: 10.1111/exd.13291] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2017] [Indexed: 12/14/2022]
Abstract
Loss-of-function melanocortin 1 receptor (MC1R) polymorphisms are common in UV-sensitive fair-skinned individuals and are associated with blunted cAMP second messenger signalling and higher lifetime risk of melanoma because of diminished ability of melanocytes to cope with UV damage. cAMP signalling positions melanocytes to resist UV injury by upregulating synthesis of UV-blocking eumelanin pigment and by enhancing the repair of UV-induced DNA damage. cAMP enhances melanocyte nucleotide excision repair (NER), the genome maintenance pathway responsible for the removal of mutagenic UV photolesions, through cAMP-activated protein kinase (protein kinase A)-mediated phosphorylation of the ataxia telangiectasia-mutated and Rad3-related (ATR) protein on the S435 residue. We investigated the interdependence of cAMP-mediated melanin upregulation and cAMP-enhanced DNA repair in primary human melanocytes and a melanoma cell line. We observed that the ATR-dependent molecular pathway linking cAMP signalling to the NER pathway is independent of MITF activation. Similarly, cAMP-mediated upregulation of pigment synthesis is independent of ATR, suggesting that the key molecular events driving MC1R-mediated enhancement of genome maintenance (eg PKA-mediated phosphorylation of ATR) and MC1R-induced pigment induction (eg MITF activation) are distinct.
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Affiliation(s)
- Erin M Wolf Horrell
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Stuart G Jarrett
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Katharine M Carter
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, USA
| | - John A D'Orazio
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA.,Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, USA.,Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY, USA
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Jarrett SG, Wolf Horrell EM, D'Orazio JA. AKAP12 mediates PKA-induced phosphorylation of ATR to enhance nucleotide excision repair. Nucleic Acids Res 2016; 44:10711-10726. [PMID: 27683220 PMCID: PMC5159552 DOI: 10.1093/nar/gkw871] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 09/16/2016] [Accepted: 09/21/2016] [Indexed: 12/30/2022] Open
Abstract
Loss-of-function in melanocortin 1 receptor (MC1R), a GS protein-coupled receptor that regulates signal transduction through cAMP and protein kinase A (PKA) in melanocytes, is a major inherited melanoma risk factor. Herein, we report a novel cAMP-mediated response for sensing and responding to UV-induced DNA damage regulated by A-kinase-anchoring protein 12 (AKAP12). AKAP12 is identified as a necessary participant in PKA-mediated phosphorylation of ataxia telangiectasia mutated and Rad3-related (ATR) at S435, a post-translational event required for cAMP-enhanced nucleotide excision repair (NER). Moreover, UV exposure promotes ATR-directed phosphorylation of AKAP12 at S732, which promotes nuclear translocation of AKAP12–ATR-pS435. This complex subsequently recruits XPA to UV DNA damage and enhances 5′ strand incision. Preventing AKAP12's interaction with PKA or with ATR abrogates ATR-pS435 accumulation, delays recruitment of XPA to UV-damaged DNA, impairs NER and increases UV-induced mutagenesis. Our results define a critical role for AKAP12 as an UV-inducible scaffold for PKA-mediated ATR phosphorylation, and identify a repair complex consisting of AKAP12–ATR-pS435-XPA at photodamage, which is essential for cAMP-enhanced NER.
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Affiliation(s)
- Stuart G Jarrett
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Erin M Wolf Horrell
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA.,Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - John A D'Orazio
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA .,Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, USA.,Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY 40536, USA.,Department of Pharmacology and Nutritional Science, University of Kentucky College of Medicine, Lexington, KY 40536, USA.,Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, USA
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Abstract
The melanocortin 1 receptor (MC1R) is a melanocytic Gs protein coupled receptor that regulates skin pigmentation, UV responses, and melanoma risk. It is a highly polymorphic gene, and loss of function correlates with a fair, UV-sensitive, and melanoma-prone phenotype due to defective epidermal melanization and sub-optimal DNA repair. MC1R signaling, achieved through adenylyl cyclase activation and generation of the second messenger cAMP, is hormonally controlled by the positive agonist melanocortin, the negative agonist agouti signaling protein, and the neutral antagonist β-defensin 3. Activation of cAMP signaling up-regulates melanin production and deposition in the epidermis which functions to limit UV penetration into the skin and enhances nucleotide excision repair (NER), the genomic stability pathway responsible for clearing UV photolesions from DNA to avoid mutagenesis. Herein we review MC1R structure and function and summarize our laboratory's findings on the molecular mechanisms by which MC1R signaling impacts NER.
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Affiliation(s)
- Erin M. Wolf Horrell
- Department of Physiology, University of Kentucky College of MedicineLexington, KY, USA
| | - Mary C. Boulanger
- Markey Cancer Center, University of Kentucky College of MedicineLexington, KY, USA
| | - John A. D’Orazio
- Department of Physiology, University of Kentucky College of MedicineLexington, KY, USA
- Markey Cancer Center, University of Kentucky College of MedicineLexington, KY, USA
- Departments of Pediatrics, Toxicology and Cancer Biology, Physiology, and Pharmacology and Nutritional Sciences, University of Kentucky College of MedicineLexington, KY, USA
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Schroder EA, Harfmann BD, Zhang X, Srikuea R, England JH, Hodge BA, Wen Y, Riley LA, Yu Q, Christie A, Smith JD, Seward T, Wolf Horrell EM, Mula J, Peterson CA, Butterfield TA, Esser KA. Intrinsic muscle clock is necessary for musculoskeletal health. J Physiol 2015; 593:5387-404. [PMID: 26486627 PMCID: PMC4704520 DOI: 10.1113/jp271436] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 10/12/2015] [Indexed: 12/21/2022] Open
Abstract
KEY POINTS The endogenous molecular clock in skeletal muscle is necessary for maintenance of phenotype and function. Loss of Bmal1 solely from adult skeletal muscle (iMSBmal1(-/-) ) results in reductions in specific tension, increased oxidative fibre type and increased muscle fibrosis with no change in feeding or activity. Disruption of the molecular clock in adult skeletal muscle is sufficient to induce changes in skeletal muscle similar to those seen in the Bmal1 knockout mouse (Bmal1(-/-) ), a model of advanced ageing. iMSBmal1(-/-) mice develop increased bone calcification and decreased joint collagen, which in combination with the functional changes in skeletal muscle results in altered gait. This study uncovers a fundamental role for the skeletal muscle clock in musculoskeletal homeostasis with potential implications for ageing. ABSTRACT Disruption of circadian rhythms in humans and rodents has implicated a fundamental role for circadian rhythms in ageing and the development of many chronic diseases including diabetes, cardiovascular disease, depression and cancer. The molecular clock mechanism underlies circadian rhythms and is defined by a transcription-translation feedback loop with Bmal1 encoding a core molecular clock transcription factor. Germline Bmal1 knockout (Bmal1 KO) mice have a shortened lifespan, show features of advanced ageing and exhibit significant weakness with decreased maximum specific tension at the whole muscle and single fibre levels. We tested the role of the molecular clock in adult skeletal muscle by generating mice that allow for the inducible skeletal muscle-specific deletion of Bmal1 (iMSBmal1). Here we show that disruption of the molecular clock, specifically in adult skeletal muscle, is associated with a muscle phenotype including reductions in specific tension, increased oxidative fibre type, and increased muscle fibrosis similar to that seen in the Bmal1 KO mouse. Remarkably, the phenotype observed in the iMSBmal1(-/-) mice was not limited to changes in muscle. Similar to the germline Bmal1 KO mice, we observed significant bone and cartilage changes throughout the body suggesting a role for the skeletal muscle molecular clock in both the skeletal muscle niche and the systemic milieu. This emerging area of circadian rhythms and the molecular clock in skeletal muscle holds the potential to provide significant insight into intrinsic mechanisms of the maintenance of muscle quality and function as well as identifying a novel crosstalk between skeletal muscle, cartilage and bone.
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Affiliation(s)
- Elizabeth A Schroder
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Brianna D Harfmann
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Xiping Zhang
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Ratchakrit Srikuea
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | | | - Brian A Hodge
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Yuan Wen
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Lance A Riley
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Qi Yu
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Alexander Christie
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Jeffrey D Smith
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Tanya Seward
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Erin M Wolf Horrell
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Jyothi Mula
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- College of Health Sciences, University of Kentucky, Lexington, KY, USA
| | - Charlotte A Peterson
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- College of Health Sciences, University of Kentucky, Lexington, KY, USA
| | - Timothy A Butterfield
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- College of Health Sciences, University of Kentucky, Lexington, KY, USA
| | - Karyn A Esser
- Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
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Jarrett SG, Horrell EMW, Christian PA, Vanover JC, Boulanger MC, Zou Y, D'Orazio JA. Abstract A34: MC1R signaling reduces UV mutagenesis by ATR-mediated recruitment of XPA to photolesions. Cancer Res 2015. [DOI: 10.1158/1538-7445.mel2014-a34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The melanocortin 1 receptor (MC1R), which signals through cAMP, is a melanocytic Gs-coupled transmembrane receptor activated by binding to its high-affinity ligand, α-melanocyte stimulating hormone (MSH). Besides influencing pigment phenotype and mediating adaptive tanning, MC1R signaling is intricately linked with genome maintenance and DNA repair. Individuals harboring loss-of-function MC1R polymorphisms are UV sensitive and melanoma-prone. We have determined that MC1R-mediated cAMP signaling promotes nucleotide excision repair (NER) in a cAMP-dependent protein kinase A (PKA)-dependent manner. PKA directly phosphorylates ataxia telangiectasia and Rad3-related protein (ATR) at Ser435 which actively recruits the key NER protein xeroderma pigmentosum complementation group A (XPA) to sites of nuclear UV photodamage, accelerating clearance of UV-induced photolesions and reducing UV mutagenesis. Loss of Ser435 within ATR prevents PKA-mediated ATR phosphorylation, disrupts ATR-XPA binding, delays recruitment of XPA to UV-damaged DNA and elevates UV-induced mutagenesis. PKA-mediated ATR phosphorylation on Ser435 appears to induce a DNA repair-specific function of ATR independent of Chk1 phosphorylation and cell cycle arrest. Importantly, MC1R signaling defects and sub-optimal DNA repair are overcome by forskolin-mediated cAMP induction in melanocytes and in whole skin. Our findings mechanistically link cAMP-PKA signaling to NER and illustrate the potential benefits of cAMP pharmacological rescue to reduce UV mutagenesis in MC1R-defective, melanoma-susceptible individuals.
Citation Format: Stuart Gordon Jarrett, Erin M. Wolf Horrell, Perry A. Christian, Jillian C. Vanover, Mary C. Boulanger, Yue Zou, John August D'Orazio. MC1R signaling reduces UV mutagenesis by ATR-mediated recruitment of XPA to photolesions. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr A34.
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Affiliation(s)
| | | | | | | | | | - Yue Zou
- 2East Tennessee State University, Johnson City, TN
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Moylan JS, Smith JD, Wolf Horrell EM, McLean JB, Deevska GM, Bonnell MR, Nikolova-Karakashian MN, Reid MB. Neutral sphingomyelinase-3 mediates TNF-stimulated oxidant activity in skeletal muscle. Redox Biol 2014; 2:910-20. [PMID: 25180167 PMCID: PMC4143815 DOI: 10.1016/j.redox.2014.07.006] [Citation(s) in RCA: 24] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 07/22/2014] [Indexed: 11/26/2022] Open
Abstract
Aims Sphingolipid and oxidant signaling affect glucose uptake, atrophy, and force production of skeletal muscle similarly and both are stimulated by tumor necrosis factor (TNF), suggesting a connection between systems. Sphingolipid signaling is initiated by neutral sphingomyelinase (nSMase), a family of agonist-activated effector enzymes. Northern blot analyses suggest that nSMase3 may be a striated muscle-specific nSMase. The present study tested the hypothesis that nSMase3 protein is expressed in skeletal muscle and functions to regulate TNF-stimulated oxidant production. Results We demonstrate constitutive nSMase activity in skeletal muscles of healthy mice and humans and in differentiated C2C12 myotubes. nSMase3 (Smpd4 gene) mRNA is highly expressed in muscle. An nSMase3 protein doublet (88 and 85 kD) is derived from alternative mRNA splicing of exon 11. The proteins partition differently. The full-length 88 kD isoform (nSMase3a) fractionates with membrane proteins that are resistant to detergent extraction; the 85 kD isoform lacking exon 11 (nSMase3b) is more readily extracted and fractionates with detergent soluble membrane proteins; neither variant is detected in the cytosol. By immunofluorescence microscopy, nSMase3 resides in both internal and sarcolemmal membranes. Finally, myotube nSMase activity and cytosolic oxidant activity are stimulated by TNF. Both if these responses are inhibited by nSMase3 knockdown. Innovation These findings identify nSMase3 as an intermediate that links TNF receptor activation, sphingolipid signaling, and skeletal muscle oxidant production. Conclusion Our data show that nSMase3 acts as a signaling nSMase in skeletal muscle that is essential for TNF-stimulated oxidant activity. First measures of endogenous nSMase3 protein in muscle. Detection of nSMase3 splice variant proteins. Identification of a functional role for nSMase3 in redox signaling. Identification of an intermediate in TNF/redox signaling.
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Affiliation(s)
- Jennifer S Moylan
- Department of Physiology, University of Kentucky, Lexington, KY, USA ; Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Jeffrey D Smith
- Department of Physiology, University of Kentucky, Lexington, KY, USA ; Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Erin M Wolf Horrell
- Department of Physiology, University of Kentucky, Lexington, KY, USA ; Center for Muscle Biology, University of Kentucky, Lexington, KY, USA ; Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - Julie B McLean
- Department of Physiology, University of Kentucky, Lexington, KY, USA ; Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Gergana M Deevska
- Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Mark R Bonnell
- Department of Surgery, University of Kentucky, Lexington, KY, USA
| | | | - Michael B Reid
- Department of Physiology, University of Kentucky, Lexington, KY, USA ; Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
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Jarrett SG, Horrell EMW, Christian PA, Vanover JC, Boulanger MC, Zou Y, D'Orazio JA. RETRACTED: PKA-mediated phosphorylation of ATR promotes recruitment of XPA to UV-induced DNA damage. Mol Cell 2014; 54:999-1011. [PMID: 24950377 PMCID: PMC4076709 DOI: 10.1016/j.molcel.2014.05.030] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 03/28/2014] [Accepted: 05/17/2014] [Indexed: 12/21/2022]
Abstract
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the authors. An investigation by the University of Kentucky (UK) recently determined that it contains fabricated and/or falsified data committed by the lead author on the paper. The results of the investigation can be viewed at https://ori.hhs.gov/content/case-summary-jarrett-stuart-g. UK identified that there were duplications and flips of panels in three figures (Figures 7D, 7E, and S3C), and original data could not be retrieved. In Figures 7D and 7E, there are inappropriate loading controls: reuse and relabeling between Figure 7D (no UV) and Figure 7E (+ UV). In Figure S3C, the loading controls for 6-4 PP (second row down) are the same as those for XPA (fourth row down), but are flipped. In both cases, the authors could not recover the original data, since primary data were stored only on a computer associated with a Storm PhosphorImager and were lost when that computer crashed. Thus, this is considered data fabrication, and the authors are retracting the paper. The authors apologize to the scientific community for any inconveniences or challenges resulting from the publication and retraction of this manuscript. Authors Stuart Jarrett and Jillian Vanover could not be reached. The remaining authors agree to the retraction.
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Affiliation(s)
- Stuart G Jarrett
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Erin M Wolf Horrell
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA; Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Perry A Christian
- Graduate Center for Toxicology, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Jillian C Vanover
- Department of Pharmacology and Nutrition Sciences, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Mary C Boulanger
- Department of Dietetics and Human Nutrition, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Yue Zou
- Department of Biochemistry and Molecular Biology, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - John A D'Orazio
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA; Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, USA; Graduate Center for Toxicology, University of Kentucky College of Medicine, Lexington, KY 40536, USA; Department of Pharmacology and Nutrition Sciences, University of Kentucky College of Medicine, Lexington, KY 40536, USA; Department of Dietetics and Human Nutrition, University of Kentucky College of Medicine, Lexington, KY 40536, USA; Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, USA.
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