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Dasgupta D, Mahadev Bhat S, Creighton C, Cortes C, Delmotte P, Sieck GC. Molecular mechanisms underlying TNFα-induced mitochondrial fragmentation in human airway smooth muscle cells. Am J Physiol Lung Cell Mol Physiol 2024; 326:L190-L205. [PMID: 38084427 DOI: 10.1152/ajplung.00198.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 06/27/2023] [Revised: 12/05/2023] [Accepted: 12/05/2023] [Indexed: 01/06/2024] Open
Abstract
Tumor necrosis factor α (TNFα), a proinflammatory cytokine, plays a significant role in mediating the effects of acute inflammation in response to allergens, pollutants, and respiratory infections. Previously, we showed that acute exposure to TNFα induces mitochondrial fragmentation in human airway smooth muscle (hASM) cells, which is associated with increased expression of dynamin-related protein 1 (DRP1). Phosphorylation of DRP1 at serine 616 (pDRP1S616) promotes its translocation and binding to the outer mitochondrial membrane (OMM) and mediates mitochondrial fragmentation. Previously, we reported that TNFα exposure triggers protein unfolding and triggers an endoplasmic reticulum (ER) stress response involving phosphorylation of inositol-requiring enzyme 1α (pIRE1α) at serine 724 (pIRE1αS724) and subsequent splicing of X-box binding protein 1 (XBP1s) in hASM cells. We hypothesize that TNFα-mediated activation of the pIRE1αS724/XBP1s ER stress pathway in hASM cells transcriptionally activates genes that encode kinases responsible for pDRP1S616 phosphorylation. Using 3-D confocal imaging of MitoTracker green-labeled mitochondria, we found that TNFα treatment for 6 h induces mitochondrial fragmentation in hASM cells. We also confirmed that 6 h TNFα treatment activates the pIRE1α/XBP1s ER stress pathway. Using in silico analysis and ChIP assay, we showed that CDK1 and CDK5, kinases involved in the phosphorylation of pDRP1S616, are transcriptionally targeted by XBP1s. TNFα treatment increased the binding affinity of XBP1s on the promoter regions of CDK1 and CDK5, and this was associated with an increase in pDRP1S616 and mitochondria fragmentation. This study reveals a new underlying molecular mechanism for TNFα-induced mitochondrial fragmentation in hASM cells.NEW & NOTEWORTHY Airway inflammation is increasing worldwide. Proinflammatory cytokines mediate an adaptive mechanism to overcome inflammation-induced cellular stress. Previously, we reported that TNFα mediates hASM cellular responses, leading to increased force and ATP consumption associated with increased O2 consumption, and oxidative stress. This study indicates that TNFα induces ER stress, which induces mitochondrial fragmentation via pIRE1αS724/XBP1s mediated CDK1/5 upregulation and pDRP1S616 phosphorylation. Mitochondrial fragmentation may promote hASM mitochondrial biogenesis to maintain healthy mitochondrial pool.
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Affiliation(s)
- Debanjali Dasgupta
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States
| | - Sanjana Mahadev Bhat
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States
| | - Claire Creighton
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States
| | - Catherin Cortes
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States
| | - Philippe Delmotte
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States
| | - Gary C Sieck
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States
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Mahadev Bhat S, Yap JQ, Ramirez-Ramirez OA, Delmotte P, Sieck GC. Cell-Based Measurement of Mitochondrial Function in Human Airway Smooth Muscle Cells. Int J Mol Sci 2023; 24:11506. [PMID: 37511264 PMCID: PMC10380259 DOI: 10.3390/ijms241411506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 06/23/2023] [Revised: 07/11/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
Cellular mitochondrial function can be assessed using high-resolution respirometry that measures the O2 consumption rate (OCR) across a number of cells. However, a direct measurement of cellular mitochondrial function provides valuable information and physiological insight. In the present study, we used a quantitative histochemical technique to measure the activity of succinate dehydrogenase (SDH), a key enzyme located in the inner mitochondrial membrane, which participates in both the tricarboxylic acid (TCA) cycle and electron transport chain (ETC) as Complex II. In this study, we determine the maximum velocity of the SDH reaction (SDHmax) in individual human airway smooth muscle (hASM) cells. To measure SDHmax, hASM cells were exposed to a solution containing 80 mM succinate and 1.5 mM nitroblue tetrazolium (NBT, reaction indicator). As the reaction proceeded, the change in optical density (OD) due to the reduction of NBT to its diformazan (peak absorbance wavelength of 570 nm) was measured using a confocal microscope with the pathlength for light absorbance tightly controlled. SDHmax was determined during the linear period of the SDH reaction and expressed as mmol fumarate/liter of cell/min. We determine that this technique is rigorous and reproducible, and reliable for the measurement of mitochondrial function in individual cells.
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Affiliation(s)
| | | | | | | | - Gary C. Sieck
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA; (S.M.B.); (J.Q.Y.); (O.A.R.-R.); (P.D.)
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Dasgupta D, Mahadev Bhat S, Price AL, Delmotte P, Sieck GC. Molecular Mechanisms Underlying TNFα-Induced Mitochondrial Biogenesis in Human Airway Smooth Muscle. Int J Mol Sci 2023; 24:5788. [PMID: 36982859 PMCID: PMC10055892 DOI: 10.3390/ijms24065788] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [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: 02/21/2023] [Revised: 03/10/2023] [Accepted: 03/15/2023] [Indexed: 03/22/2023] Open
Abstract
Proinflammatory cytokines such as TNFα mediate airway inflammation. Previously, we showed that TNFα increases mitochondrial biogenesis in human ASM (hASM) cells, which is associated with increased PGC1α expression. We hypothesized that TNFα induces CREB and ATF1 phosphorylation (pCREBS133 and pATF1S63), which transcriptionally co-activate PGC1α expression. Primary hASM cells were dissociated from bronchiolar tissue obtained from patients undergoing lung resection, cultured (one-three passages), and then differentiated by serum deprivation (48 h). hASM cells from the same patient were divided into two groups: TNFα (20 ng/mL) treated for 6 h and untreated controls. Mitochondria were labeled using MitoTracker green and imaged using 3D confocal microscopy to determine mitochondrial volume density. Mitochondrial biogenesis was assessed based on relative mitochondrial DNA (mtDNA) copy number determined by quantitative real-time PCR (qPCR). Gene and/or protein expression of pCREBS133, pATF1S63, PCG1α, and downstream signaling molecules (NRFs, TFAM) that regulate transcription and replication of the mitochondrial genome, were determined by qPCR and/or Western blot. TNFα increased mitochondrial volume density and mitochondrial biogenesis in hASM cells, which was associated with an increase in pCREBS133, pATF1S63 and PCG1α expression, with downstream transcriptional activation of NRF1, NRF2, and TFAM. We conclude that TNFα increases mitochondrial volume density in hASM cells via a pCREBS133/pATF1S63/PCG1α-mediated pathway.
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Affiliation(s)
| | | | | | | | - Gary C. Sieck
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA
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Dasgupta D, Delmotte P, Mahadev Bhat S, Creighton C, Han YS, Cortes Botero C, Sieck GC. TNFα Mediated Endoplasmic Reticulum Stress Promotes Differential Phosphorylation of DRP1 and Mitochondrial Fragmentation in Human Airway Smooth Muscle Cells. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r3133] [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)
- Debanjali Dasgupta
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMN
| | - Philippe Delmotte
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMN
| | | | - Claire Creighton
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMN
| | - Young S. Han
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMN
| | | | - Gary C. Sieck
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMN
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Mahadev Bhat S, Yap JQ, Ramirez Ramirez OA, Delmotte P, Sieck GC. Single Cell Assessment of Mitochondrial Function. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r3283] [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)
| | - Jane Q. Yap
- Physiology and Biomedical EngineeringMayo ClinicRochesterMN
| | | | | | - Gary C. Sieck
- Physiology and Biomedical EngineeringMayo ClinicRochesterMN
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Yap JQ, Mahadev Bhat S, Ramirez Ramirez OA, Delmotte P, Sieck GC. TNFα Reduces the Maximum Respiratory Capacity of Mitochondria in Human Airway Smooth Muscle Cells. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r2260] [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)
- Jane Q. Yap
- Physiology and Biomedical EngineeringMayo ClinicRochesterMN
| | | | | | | | - Gary C. Sieck
- Physiology and Biomedical EngineeringMayo ClinicRochesterMN
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Bhat SM, Massey N, Shrestha D, Karriker LA, Jelesijević T, Wang C, Charavaryamath C. Transcriptomic and ultrastructural evidence indicate that anti-HMGB1 antibodies rescue organic dust-induced mitochondrial dysfunction. Cell Tissue Res 2022; 388:373-398. [PMID: 35244775 PMCID: PMC10155187 DOI: 10.1007/s00441-022-03602-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 08/04/2021] [Accepted: 02/22/2022] [Indexed: 11/02/2022]
Abstract
Exposure to organic dust (OD) in agriculture is known to cause respiratory symptoms including loss of lung function. OD exposure activates multiple signaling pathways since it contains a variety of microbial products and particulate matter. Previously, we have shown how OD exposure leads to the secretion of HMGB1 and HMGB1-RAGE signaling, and how this can be a possible therapeutic target to reduce inflammation. Cellular mitochondria are indispensable for homeostasis and are emerging targets to curtail inflammation. Recently, we have also observed that OD exposure induces mitochondrial dysfunction characterized by loss of structural integrity and deficits in bioenergetics. However, the role of HMGB1 in OD-induced mitochondrial dysfunction in human bronchial epithelial (NHBE) cells remains elusive. Therefore, we aimed to study whether decreased levels of intracellular HMGB1 or antibody-mediated neutralization of secreted HMGB1 would rescue mitochondrial dysfunction. Single and repeated ODE exposure showed an elongated mitochondrial network and cristolysis whereas HMGB1 neutralization or the lack thereof promotes mitochondrial biogenesis evidenced by increased mitochondrial fragmentation, increased DRP1 expression, decreased MFN2 expression, and increased PGC1α expression. Repeated 5-day ODE exposure significantly downregulated transcripts encoding mitochondrial respiration and metabolism (ATP synthase, NADUF, and UQCR) as well as glucose uptake. This was reversed by the antibody-mediated neutralization of HMGB1. Our results support our hypothesis that, in NHBE cells, neutralization of ODE-induced HMGB1 secretion rescues OD-induced mitochondrial dysfunction.
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Affiliation(s)
- Sanjana Mahadev Bhat
- Department of Biomedical Sciences, Iowa State University, Ames, IA, USA
- Immunobiology Interdepartmental Graduate Program, Iowa State University, Ames, IA, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Nyzil Massey
- Department of Biomedical Sciences, Iowa State University, Ames, IA, USA
| | - Denusha Shrestha
- Department of Biomedical Sciences, Iowa State University, Ames, IA, USA
| | - Locke A Karriker
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA
| | - Tomislav Jelesijević
- Department of Comparative Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Chong Wang
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA
- Department of Statistics, Iowa State University, Ames, IA, USA
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Shrestha D, Massey N, Bhat SM, Jelesijević T, Sahin O, Zhang Q, Bailey KL, Poole JA, Charavaryamath C. Nrf2 Activation Protects Against Organic Dust and Hydrogen Sulfide Exposure Induced Epithelial Barrier Loss and K. pneumoniae Invasion. Front Cell Infect Microbiol 2022; 12:848773. [PMID: 35521223 PMCID: PMC9062039 DOI: 10.3389/fcimb.2022.848773] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 03/21/2022] [Indexed: 11/23/2022] Open
Abstract
Agriculture workers report various respiratory symptoms owing to occupational exposure to organic dust (OD) and various gases. Previously, we demonstrated that pre-exposure to hydrogen sulfide (H2S) alters the host response to OD and induces oxidative stress. Nrf2 is a master-regulator of host antioxidant response and exposures to toxicants is known to reduce Nrf2 activity. The OD exposure-induced lung inflammation is known to increase susceptibility to a secondary microbial infection. We tested the hypothesis that repeated exposure to OD or H2S leads to loss of Nrf2, loss of epithelial cell integrity and that activation of Nrf2 rescues this epithelial barrier dysfunction. Primary normal human bronchial epithelial (NHBE) cells or mouse precision cut-lung slices (PCLS) were treated with media, swine confinement facility organic dust extract (ODE) or H2S or ODE+H2S for one or five days. Cells were also pretreated with vehicle control (DMSO) or RTA-408, a Nrf2 activator. Acute exposure to H2S and ODE+H2S altered the cell morphology, decreased the viability as per the MTT assay, and reduced the Nrf2 expression as well as increased the keap1 levels in NHBE cells. Repeated exposure to ODE or H2S or ODE+H2S induced oxidative stress and cytokine production, decreased tight junction protein occludin and cytoskeletal protein ezrin expression, disrupted epithelial integrity and resulted in increased Klebsiella pneumoniae invasion. RTA-408 (pharmacological activator of Nrf2) activated Nrf2 by decreasing keap1 levels and reduced ODE+H2S-induced changes including reversing loss of barrier integrity, inflammatory cytokine production and microbial invasion in PCLS but not in NHBE cell model. We conclude that Nrf2 activation has a partial protective function against ODE and H2S.
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Affiliation(s)
- Denusha Shrestha
- Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
| | - Nyzil Massey
- Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
| | - Sanjana Mahadev Bhat
- Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
- Immunobiology Interdepartmental Graduate Program, Iowa State University, Ames, IA, United States
| | - Tomislav Jelesijević
- Department of Comparative Biomedical Sciences, Louisiana State University, Baton Rouge, LA, United States
| | - Orhan Sahin
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, United States
| | - Qijing Zhang
- Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, United States
| | - Kristina L. Bailey
- Department of Internal Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, University of Nebraska Medical Center, Omaha, NE, United States
| | - Jill A. Poole
- Department of Medicine, University of Nebraska Medical Center, Omaha, NE, United States
| | - Chandrashekhar Charavaryamath
- Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
- *Correspondence: Chandrashekhar Charavaryamath,
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Massey N, Shrestha D, Bhat SM, Padhi P, Wang C, Karriker LA, Smith JD, Kanthasamy AG, Charavaryamath C. Mitoapocynin Attenuates Organic Dust Exposure-Induced Neuroinflammation and Sensory-Motor Deficits in a Mouse Model. Front Cell Neurosci 2022; 16:817046. [PMID: 35496912 PMCID: PMC9043522 DOI: 10.3389/fncel.2022.817046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 03/14/2022] [Indexed: 11/13/2022] Open
Abstract
Increased incidences of neuro-inflammatory diseases in the mid-western United States of America (USA) have been linked to exposure to agriculture contaminants. Organic dust (OD) is a major contaminant in the animal production industry and is central to the respiratory symptoms in the exposed individuals. However, the exposure effects on the brain remain largely unknown. OD exposure is known to induce a pro-inflammatory phenotype in microglial cells. Further, blocking cytoplasmic NOX-2 using mitoapocynin (MA) partially curtail the OD exposure effects. Therefore, using a mouse model, we tested a hypothesis that inhaled OD induces neuroinflammation and sensory-motor deficits. Mice were administered with either saline, fluorescent lipopolysaccharides (LPSs), or OD extract intranasally daily for 5 days a week for 5 weeks. The saline or OD extract-exposed mice received either a vehicle or MA (3 mg/kg) orally for 3 days/week for 5 weeks. We quantified inflammatory changes in the upper respiratory tract and brain, assessed sensory-motor changes using rotarod, open-field, and olfactory test, and quantified neurochemicals in the brain. Inhaled fluorescent LPS (FL-LPS) was detected in the nasal turbinates and olfactory bulbs. OD extract exposure induced atrophy of the olfactory epithelium with reduction in the number of nerve bundles in the nasopharyngeal meatus, loss of cilia in the upper respiratory epithelium with an increase in the number of goblet cells, and increase in the thickness of the nasal epithelium. Interestingly, OD exposure increased the expression of HMGB1, 3- nitrotyrosine (NT), IBA1, glial fibrillary acidic protein (GFAP), hyperphosphorylated Tau (p-Tau), and terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL)-positive cells in the brain. Further, OD exposure decreased time to fall (rotarod), total distance traveled (open-field test), and olfactory ability (novel scent test). Oral MA partially rescued olfactory epithelial changes and gross congestion of the brain tissue. MA treatment also decreased the expression of HMGB1, 3-NT, IBA1, GFAP, and p-Tau, and significantly reversed exposure induced sensory-motor deficits. Neurochemical analysis provided an early indication of depressive behavior. Collectively, our results demonstrate that inhalation exposure to OD can cause sustained neuroinflammation and behavior deficits through lung-brain axis and that MA treatment can dampen the OD-induced inflammatory response at the level of lung and brain.
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Affiliation(s)
- Nyzil Massey
- Biomedical Sciences, Iowa State University, Ames, IA, United States
| | - Denusha Shrestha
- Biomedical Sciences, Iowa State University, Ames, IA, United States
| | | | - Piyush Padhi
- Biomedical Sciences, Iowa State University, Ames, IA, United States
| | - Chong Wang
- Veterinary Diagnostic and Production Animal Medicine (VDPAM), Iowa State University, Ames, IA, United States
- Statistics, Iowa State University, Ames, IA, United States
| | - Locke A. Karriker
- Veterinary Diagnostic and Production Animal Medicine (VDPAM), Iowa State University, Ames, IA, United States
| | - Jodi D. Smith
- Veterinary Pathology, Iowa State University, Ames, IA, United States
| | | | - Chandrashekhar Charavaryamath
- Biomedical Sciences, Iowa State University, Ames, IA, United States
- *Correspondence: Chandrashekhar Charavaryamath ; orcid.org/0000-0002-5217-1608
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Massey N, Shrestha D, Bhat SM, Kondru N, Charli A, Karriker LA, Kanthasamy AG, Charavaryamath C. Organic dust-induced mitochondrial dysfunction could be targeted via cGAS-STING or cytoplasmic NOX-2 inhibition using microglial cells and brain slice culture models. Cell Tissue Res 2021; 384:465-486. [PMID: 33687557 DOI: 10.1007/s00441-021-03422-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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: 11/25/2020] [Accepted: 01/21/2021] [Indexed: 12/12/2022]
Abstract
Organic dust (OD) exposure in animal production industries poses serious respiratory and other health risks. OD consisting of microbial products and particulate matter and OD exposure-induced respiratory inflammation are under investigation. However, the effect of OD exposure on brain remains elusive. We show that OD exposure of microglial cells induces an inflammatory phenotype with the release of mitochondrial DNA (mt-DNA). Therefore, we tested a hypothesis that OD exposure-induced secreted mt-DNA signaling drives the inflammation. A mouse microglial cell line was treated with medium or organic dust extract (ODE, 1% v/v) along with either phosphate-buffered saline (PBS) or mitoapocynin (MA, 10 µmol). Microglia treated with control or anti-STING siRNA were exposed to medium or ODE. Mouse organotypic brain slice cultures (BSCs) were exposed to medium or ODE with or without MA. Various samples were processed to quantify mitochondrial reactive oxygen species (mt-ROS), mt-DNA, cytochrome c, TFAM, mitochondrial stress markers and mt-DNA-induced signaling via cGAS-STING and TLR9. Data were analyzed and a p value of ≤ 0.05 was considered significant. MA treatment decreased the ODE-induced mt-DNA release into the cytosol. ODE increased MFN1/2 and PINK1 but not DRP1 and MA treatment decreased the MFN2 expression. MA treatment decreased the ODE exposure-induced mt-DNA signaling via cGAS-STING and TLR9. Anti-STING siRNA decreased the ODE-induced increase in IRF3, IFN-β and IBA-1 expression. In BSCs, MA treatment decreased the ODE-induced TNF-α, IL-6 and MFN1. Therefore, OD exposure-induced mt-DNA signaling was curtailed through cytoplasmic NOX-2 inhibition or STING suppression to reduce brain microglial inflammatory response.
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Affiliation(s)
- Nyzil Massey
- Department of Biomedical Sciences, Veterinary Medicine Building, Iowa State University, Ames, IA, 50011, USA
| | - Denusha Shrestha
- Department of Biomedical Sciences, Veterinary Medicine Building, Iowa State University, Ames, IA, 50011, USA
| | - Sanjana Mahadev Bhat
- Department of Biomedical Sciences, Veterinary Medicine Building, Iowa State University, Ames, IA, 50011, USA
| | | | | | - Locke A Karriker
- Department of Veterinary Diagnostic and Production Animal Medicine, Iowa State University, Ames, IA, USA
| | - Anumantha G Kanthasamy
- Department of Biomedical Sciences, Veterinary Medicine Building, Iowa State University, Ames, IA, 50011, USA
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Shrestha D, Bhat SM, Massey N, Santana Maldonado C, Rumbeiha WK, Charavaryamath C. Pre-exposure to hydrogen sulfide modulates the innate inflammatory response to organic dust. Cell Tissue Res 2021; 384:129-148. [PMID: 33409657 DOI: 10.1007/s00441-020-03333-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 10/29/2020] [Indexed: 01/31/2023]
Abstract
Animal production units produce and store many contaminants on-site, including organic dust (OD) and hydrogen sulfide (H2S). Workers in these settings report various respiratory disease symptoms. Both OD and H2S have shown to induce lung inflammation. However, impact of co-exposure to both H2S and OD has not been investigated. Therefore, we tested a hypothesis that pre-exposure to H2S modulates the innate inflammatory response of the lungs to organic dust. In a mouse model of H2S and organic dust extract (ODE) exposure, we assessed lung inflammation quantitatively. We exposed human airway epithelial and monocytic cells to medium or H2S alone or H2S followed by ODE and measured cell viability, oxidative stress, and other markers of inflammation. Exposure to 10 ppm H2S followed by ODE increased the lavage fluid leukocytes. However, exposure to 10 ppm H2S alone resulted in changes in tight junction proteins, an increase in mRNA levels of tlr2 and tlr4 as well as ncf1, ncf4, hif1α, and nrf2. H2S alone or H2S and ODE exposure decreased cell viability and increased reactive nitrogen species production. ODE exposure increased the transcripts of tlr2 and tlr4 in both in vitro and in vivo models, whereas increased nfkbp65 transcripts following exposure to ODE and H2S was seen only in in vitro model. H2S alone and H2S followed by ODE exposure increased the levels of IL-1β. We conclude that pre-exposure to H2S modulates lung innate inflammatory response to ODE.
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Affiliation(s)
- Denusha Shrestha
- Biomedical Sciences, Iowa State University, Ames, IA, 50011, USA
| | - Sanjana Mahadev Bhat
- Biomedical Sciences, Iowa State University, Ames, IA, 50011, USA.,Immunobiology Interdepartmental Graduate Program, Iowa State University, Ames, IA, 50011, USA
| | - Nyzil Massey
- Biomedical Sciences, Iowa State University, Ames, IA, 50011, USA
| | | | - Wilson K Rumbeiha
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
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Massey N, Puttachary S, Bhat SM, Kanthasamy AG, Charavaryamath C. HMGB1-RAGE Signaling Plays a Role in Organic Dust-Induced Microglial Activation and Neuroinflammation. Toxicol Sci 2020; 169:579-592. [PMID: 30859215 DOI: 10.1093/toxsci/kfz071] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Occupational exposure to contaminants in agriculture and other industries is known to cause significant respiratory ailments. The effect of organic dust on lung inflammation and tissue remodeling has been actively investigated over many years but the adverse effect of organic dust-exposure on the central vital organ brain is beginning to emerge. Brain microglial cells are a major driver of neuroinflammation upon exposure to danger signals. Therefore, we tested a hypothesis that organic dust-exposure of microglial cells induces microglial cell activation and inflammation through HMGB1-RAGE signaling. Mouse microglial cells were exposed to organic dust extract showed a time-dependent increase in cytoplasmic translocation of high-mobility group box 1 (HMGB1) from the nucleus, increased expression of receptor for advanced glycation end products (RAGE) and activation of Iba1 as compared to control cells. Organic dust also induced reactive oxygen species generation, NF-κB activation, and proinflammatory cytokine release. To establish a functional relevance of HMGB1-RAGE activation in microglia-mediated neuroinflammation, we used both pharmacological and genetic approaches involving HMGB1 translocation inhibitor ethyl pyruvate (EP), anti-HMGB1 siRNA, and NOX-inhibitor mitoapocynin. Interestingly, EP effectively reduced HMGB1 nucleocytoplasmic translocation and RAGE expression along with reactive oxygen species (ROS) generation and TNF-α and IL-6 production but not NF-κB activation. HMGB1 knockdown by siRNA also reduced both ROS and reactive nitrogen species (RNS) and IL-6 levels but not TNF-α. NOX2 inhibitor mitoapocynin significantly reduced RNS levels. Collectively, our results demonstrate that organic dust activates HMGB1-RAGE signaling axis to induce a neuroinflammatory response in microglia and that attenuation of HMGB1-RAGE activation by EP and mitoapocynin treatments or genetic knockdown can dampen the neuroinflammation.
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Affiliation(s)
- Nyzil Massey
- *Biomedical Sciences, Iowa State University, Ames, Iowa 50011
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Bhat SM, Massey N, Karriker LA, Singh B, Charavaryamath C. Ethyl pyruvate reduces organic dust-induced airway inflammation by targeting HMGB1-RAGE signaling. Respir Res 2019; 20:27. [PMID: 30728013 PMCID: PMC6364446 DOI: 10.1186/s12931-019-0992-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [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: 07/13/2018] [Accepted: 01/27/2019] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Animal production workers are persistently exposed to organic dust and can suffer from a variety of respiratory disease symptoms and annual decline in lung function. The role of high mobility group box-1 (HMGB1) in inflammatory airway diseases is emerging. Hence, we tested a hypothesis that organic dust exposure of airway epithelial cells induces nucleocytoplasmic translocation of HMGB1 and blocking this translocation dampens organic dust-induced lung inflammation. METHODS Rats were exposed to either ambient air or swine barn (8 h/day for either 1, 5, or 20 days) and lung tissues were processed for immunohistochemistry. Swine barn dust was collected and organic dust extract (ODE) was prepared and sterilized. Human airway epithelial cell line (BEAS-2B) was exposed to either media or organic dust extract followed by treatment with media or ethyl pyruvate (EP) or anti-HMGB1 antibody. Immunoblotting, ELISA and other assays were performed at 0 (control), 6, 24 and 48 h. Data (as mean ± SEM) was analyzed using one or two-way ANOVA followed by Bonferroni's post hoc comparison test. A p value of less than 0.05 was considered significant. RESULTS Compared to controls, barn exposed rats showed an increase in the expression of HMGB1 in the lungs. Compared to controls, ODE exposed BEAS-2B cells showed nucleocytoplasmic translocation of HMGB1, co-localization of HMGB1 and RAGE, reactive species and pro-inflammatory cytokine production. EP treatment reduced the ODE induced nucleocytoplasmic translocation of HMGB1, HMGB1 expression in the cytoplasmic fraction, GM-CSF and IL-1β production and augmented the production of TGF-β1 and IL-10. Anti-HMGB1 treatment reduced ODE-induced NF-κB p65 expression, IL-6, ROS and RNS but augmented TGF-β1 and IL-10 levels. CONCLUSIONS HMGB1-RAGE signaling is an attractive target to abrogate OD-induced lung inflammation.
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Affiliation(s)
- Sanjana Mahadev Bhat
- Department of Biomedical Sciences, 2008 Vet Med Building, Iowa State University, Ames, IA, USA
| | - Nyzil Massey
- Department of Biomedical Sciences, 2008 Vet Med Building, Iowa State University, Ames, IA, USA
| | - Locke A Karriker
- Department of Veterinary Diagnostic and Production Animal Medicine, 2203 Lloyd Veterinary Medical Center, Iowa State university, Ames, IA, USA
| | - Baljit Singh
- Faculty of Veterinary Medicine, 2500 University Dr. NW, University of Calgary, Calgary, T2N 1N4, Canada
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Soman S, Bhat SM, Latha KS, Praharaj SK. Gender Differences in Perceived Social Support and Stressful Life Events in Depressed Patients. East Asian Arch Psychiatry 2016; 26:22-29. [PMID: 27086757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To study the gender differences in perceived social support and life events in patients with depression. METHODS A total of 118 patients aged 18 to 60 years, with depressive disorder according to the DSM-IV-TR, were evaluated using the Multidimensional Scale of Perceived Social Support and Presumptive Stressful Life Events Scale. RESULTS The perceived social support score was significantly higher in males than females (p < 0.001). Males perceived significantly higher social support from friends than females (p < 0.001), whereas support from significant others was higher in females. There was a higher mean number of total life events as well as specific type of life events in males that became apparent after controlling for education (p < 0.05). Financial loss or problems was the most commonly reported life event in both males and females. Work-related problems were more commonly reported by males, whereas family and marital conflict were more frequently reported by females. CONCLUSION Perceived social support and stressful life events were higher in males with depression than females.
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Affiliation(s)
- S Soman
- Department of Psychiatry, Kasturba Medical College, Manipal, Karnataka, India 576104
| | - S M Bhat
- Department of Psychiatry, Kasturba Medical College, Manipal, Karnataka, India 576104
| | - K S Latha
- Department of Psychiatry, Dr A. V. Baliga Memorial Hospital, Doddanagudde, Udupi, Karnataka, India 576102
| | - S K Praharaj
- Department of Psychiatry, Kasturba Medical College, Manipal, Karnataka, India 576104
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Pradhan NP, Bhat SM, Ghadage DP. Nosocomial infections in the medical ICU: a retrospective study highlighting their prevalence, microbiological profile and impact on ICU stay and mortality. J Assoc Physicians India 2014; 62:18-21. [PMID: 25906516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
OBJECTIVES 1. To study the prevalence of nosocomial infections in the Medical ICU. 2. To determine common microorganisms causing nosocomial infections in the ICU and their antibiotic- sensitivity profile. 3. To study the impact of nosocomial infections on ICU stay and mortality. METHODS A retrospective 1 year analysis of nosocomial infections in the Medical ICU at Smt. Kashibai Navale Medical College and Hospital, Pune, between January and December 2011 was carried out. Prevalence of nosocomial infections was determined; sites of nosocomial infections and common causative microorganisms were identified; their antibiotic-sensitivity profiles were studied. The group of patients with nosocomial infections was matched with a control group drawn from the pool of patients without nosocomial infections; this matching was done with respect to age, gender and clinical diagnosis. Period of ICU stay and patient mortality rates in the two groups were analysed. RESULTS A total of 366 ICU patient records were analysed. Of these, 32 patients were found-to have developed 35 nosocomial infections (9.6% prevalence), of which respiratory infections were the commonest (65.8%), followed by urinary infections (17.1%) and dual infections (urinary plus respiratory) (17.1%).The most frequently isolated microorganism causing respiratory infections was Acinetobacter (40.4%), 21% isolates of which were multidrug resistant; whereas the most frequently isolated microorganism causing urinary tract infections was Pseudomonas (38.4%). Average ICU stay in patients with and without nosocomial infections was 16.5 and 6.4 days respectively; whereas mortality in the two groups was 28.1% and 31.2% respectively. Overall ICU mortality was 19.9%. CONCLUSION The nosocomial infection rate in our ICU was in keeping with the rate in many industrialised countries. The most common site of nosocomial infection was the respiratory tract, followed by the urinary tract. Acinetobacter was the commonest respiratory isolate, whereas Pseudomonas was the commonest urinary isolate. One fourth of Acinetobacter isolates were multidrug resistant. Nosocomial infections resulted in a statistically significant increase in ICU stay; whereas there was no impact on ICU mortality.
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Vollala VR, Nagabhooshana S, Bhat SM, Potu BK, Rakesh V. Multiple accessory structures in the upper limb of a single cadaver. Singapore Med J 2008; 49:e254-e258. [PMID: 18830534] [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: 05/26/2023]
Abstract
The arterial and muscular variations of the upper limbs are common but important with regard to surgical approaches. Even though anomalies of the coracobrachialis muscle are rare, anatomical variations of the biceps brachii, existence of the accessory muscles in the forearm and persistent median artery are known and well documented. During routine dissection, we observed some important anatomical variations in a 50-year-old male cadaver. The variations were unilateral. The anomalies were: third head for biceps brachii muscle, an accessory belly for coracobrachialis muscle crossing the median nerve and brachial vessels and continuing with the medial head of triceps brachii muscle to be inserted to the olecranon process (coracoulnaris), a persistent median artery and an additional muscle in the anterior compartment of forearm. Although there are individual reports about these variations, the combination of these variations in one cadaver has not previously been described in the literature. Awareness of these variations is necessary to avoid complications during radiodiagnostic procedures or surgeries in the upper limb.
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Affiliation(s)
- V R Vollala
- Department of Anatomy, Melaka Manipal Medical College, Manipal University, Manipal 576104, Karnataka, India.
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17
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Vollala VR, Nagabhooshana S, Bhat SM, Rodrigues V, Rao M, Pamidi N, Surendran S. Rare anatomical variant: arterial circle in palm and at the base of the thumb. Rom J Morphol Embryol 2008; 49:585-587. [PMID: 19050813] [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] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In this article, we describe anomalous formation, distribution of superficial palmar arch and an arterial circle at the base of the thumb found during routine dissection classes in the right hand of a 45-year-old male cadaver. These variations are unique and provide significant information to surgeons dissecting the hand region.
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Affiliation(s)
- Venkata Ramana Vollala
- Department of Anatomy, Melaka Manipal Medical College (Manipal Campus), Manipal, Karnataka, India.
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Rao M, Bhat SM, Venkataramana V, Deepthinath R, Bolla SR. Bilateral prehilar multiple branching of renal arteries: a case report and literature review. Kathmandu Univ Med J (KUMJ) 2006; 4:345-348. [PMID: 18603933] [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: 05/26/2023]
Abstract
Proper knowledge of variations of the arteries supplying the kidney is essential not only to the anatomists but also to the surgeons. In the present paper we are reporting a case of bilateral early and multiple branching of the renal arteries. The origin of the 2 renal arteries was normal but soon after their origin they ended by giving rise to multiple branches. Most of these branches entered the kidney through the hilum. However, on both sides, one of the branches (superior polar artery) passed superolaterally to reach the upper pole of the kidney. The superior polar artery also gave rise to the inferior suprarenal artery. Further, related literature review is done and the urological implications of these variations in renal surgeries are discussed.
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Affiliation(s)
- M Rao
- Department of Anatomy, Melaka Manipal Medical College, Manipal Campus, Manipal, India.
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Abstract
BACKGROUND Passive suicidal thoughts are relatively common in patients with terminal cancer. There is a need for more information about the factors that influence these patients to desire death. AIM To examine the prevalence of suicidal ideation among terminally ill cancer patients. METHODS Fifty-four terminally ill inpatients (27 men and 27 women) from the palliative care unit of the Oncology department of Kasturba Hospital, Manipal were evaluated on various rating scales for depression, hopelessness and suicidal ideation, and the correlation of suicidal ideation with medical symptoms such as pain, as well as awareness of the diagnosis and understanding of the illness. RESULTS Most patients (79.7%) denied having suicidal thoughts or wishing for an early death; only 9.2% had severe suicidal ideation. Two patients (3.8%) with severe suicidal ideation had a past history of major depression. Factors such as the presence of pain, awareness of the diagnosis and understanding of the illness contributed to depressive mood states. CONCLUSION Suicidal ideation and a desire for death appear to be linked exclusively to the presence of a mental disorder. In addition, poor pain control, and awareness of the diagnosis may also contribute to suicidal ideation.
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Affiliation(s)
- K S Latha
- Associate Professor Department of Psychiatry, Kasturba Hospital, Manipal 576119, Udupi
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Dhar PK, Devi S, Rao TR, Kumari U, Joseph A, Kumar MR, Nayak S, Shreemati Y, Bhat SM, Bhat KR. Significance of lymphocytic sister chromatid exchange frequencies in ovarian cancer patients. Cancer Genet Cytogenet 1996; 89:105-8. [PMID: 8697412 DOI: 10.1016/0165-4608(95)00071-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Very few studies report the analysis of sister chromatid exchanges in ovarian cancer patients. We tested the null hypothesis that SCE frequency increases with the advancing stages of ovarian cancer and follows a Poisson distribution. As controls we examined age- and sex-matched healthy volunteers who had no such past history. An increased average SCE frequency was observed in ovarian cancer patients (6.34 +/- 0.09) vis-à-vis controls (4.47 +/- 0.12). Further, the data also suggested a stage-wise increase in the SCE frequency.
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Affiliation(s)
- P K Dhar
- Department of Anatomy, Kasturba Medical College, Manipal, India
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Latha KS, Bhat SM, D'Souza P. Suicide attempters in a general hospital unit in India: their socio-demographic and clinical profile--emphasis on cross-cultural aspects. Acta Psychiatr Scand 1996; 94:26-30. [PMID: 8841673 DOI: 10.1111/j.1600-0447.1996.tb09820.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The number of suicide attempts in developing countries has been increasing progressively, as in the West. It is important to note that much of the data on suicidal behaviour is based on information obtained from developed Western societies. All such data need to be evaluated within their specific cultural context as well as cross-culturally. The present study explored the various socio-demographic, clinical characteristics of suicide attempters in a general hospital unit in India. There were certain findings that contrasted markedly with those observed in the West. Male suicides tended to predominate here, as in many Indian studies. None of them were living alone, separated or deserted by their partner. Some suicide attempters continued to live with their extended family. There was virtually no alcohol consumption by female suicide attempters. The commonest agents used were organophosphates and other household poisons. Several cross-cultural variations in the suicidal act emerged compared to the West. The 'suicide potential' in the Indian culture is discussed.
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Affiliation(s)
- K S Latha
- Department of Psychiatry, Kasturba Medical College Hospital, Manipal, India
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22
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Dhar PK, Kumar MR, Nayak S, Rao TR, Joseph A, Devi S, Kumari U, Bhat SM, Bhat KR. A rapid silver staining and destaining technique for the nucleolus organizer region. Biotech Histochem 1995; 70:302-3. [PMID: 9044659 DOI: 10.3109/10520299509108337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Silver staining of nucleolar organizing regions (NOR) is common, but a standard protocol is lacking. A modification of a rapid silver nitrate staining technique for NORs is presented here. Advantages of the modified technique include reliability, speed, cost and the fact that it can be carried out in the light.
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Affiliation(s)
- P K Dhar
- Department of Anatomy, Human Genetics Section, Kasturba Medical College, Manipal, Karnataka, India
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Abstract
Dependence on mephentermine, a widely used sympathomimetic pressor agent, is so far unreported, although misuse of inhalers is recognised. A case of mephentermine dependence associated with chronic psychosis is reported here. Psychosis initially surfaced with chronic dexamphetamine abuse, but was sustained for 3 years by mephentermine. After a period of remission lasting for 4 years, the patient again developed psychosis on restarting abuse of mephentermine, which lasted for 5 years.
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Affiliation(s)
- G J Uday
- Department of Psychiatry, Kasturba Medical College Hospital, Manipal, India
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Chatterjee H, Bhat SM. Incarcerated umbilical hernia in children. J Indian Med Assoc 1986; 84:238-9. [PMID: 3559230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Chatterjee H, Bhat SM, Reddy KS, Barua SK, Sankaran V. Congenital solitary nonparasitic cyst of the liver in an infant. Indian J Gastroenterol 1985; 4:107-8. [PMID: 3845909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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