1
|
Awuah WA, Roy S, Tan JK, Adebusoye FT, Qiang Z, Ferreira T, Ahluwalia A, Shet V, Yee ALW, Abdul‐Rahman T, Papadakis M. Exploring the current landscape of single-cell RNA sequencing applications in gastric cancer research. J Cell Mol Med 2024; 28:e18159. [PMID: 38494861 PMCID: PMC10945075 DOI: 10.1111/jcmm.18159] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 12/22/2023] [Accepted: 01/12/2024] [Indexed: 03/19/2024] Open
Abstract
Gastric cancer (GC) represents a major global health burden and is responsible for a significant number of cancer-related fatalities. Its complex nature, characterized by heterogeneity and aggressive behaviour, poses considerable challenges for effective diagnosis and treatment. Single-cell RNA sequencing (scRNA-seq) has emerged as an important technique, offering unprecedented precision and depth in gene expression profiling at the cellular level. By facilitating the identification of distinct cell populations, rare cells and dynamic transcriptional changes within GC, scRNA-seq has yielded valuable insights into tumour progression and potential therapeutic targets. Moreover, this technology has significantly improved our comprehension of the tumour microenvironment (TME) and its intricate interplay with immune cells, thereby opening avenues for targeted therapeutic strategies. Nonetheless, certain obstacles, including tumour heterogeneity and technical limitations, persist in the field. Current endeavours are dedicated to refining protocols and computational tools to surmount these challenges. In this narrative review, we explore the significance of scRNA-seq in GC, emphasizing its advantages, challenges and potential applications in unravelling tumour heterogeneity and identifying promising therapeutic targets. Additionally, we discuss recent developments, ongoing efforts to overcome these challenges, and future prospects. Although further enhancements are required, scRNA-seq has already provided valuable insights into GC and holds promise for advancing biomedical research and clinical practice.
Collapse
Affiliation(s)
| | - Sakshi Roy
- School of MedicineQueen's University BelfastBelfastUK
| | | | | | - Zekai Qiang
- Department of Oncology & MetabolismThe University of SheffieldSheffieldUK
| | - Tomas Ferreira
- Department of Clinical Neurosciences, School of Clinical MedicineUniversity of CambridgeCambridgeUK
| | | | - Vallabh Shet
- Faculty of MedicineBangalore Medical College and Research InstituteBangaloreKarnatakaIndia
| | | | | | - Marios Papadakis
- Department of Surgery II, University Hospital Witten‐HerdeckeUniversity of Witten‐HerdeckeWuppertalGermany
| |
Collapse
|
2
|
Abdul‐Rahman T, Herrera‐Calderón RE, Ahluwalia A, Wireko AA, Ferreira T, Tan JK, Wolfson M, Ghosh S, Horbas V, Garg V, Perveen A, Papadakis M, Ashraf GM, Alexiou A. The potential of phosphorylated α-synuclein as a biomarker for the diagnosis and monitoring of multiple system atrophy. CNS Neurosci Ther 2024; 30:e14678. [PMID: 38572788 PMCID: PMC10993367 DOI: 10.1111/cns.14678] [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: 09/01/2023] [Revised: 02/29/2024] [Accepted: 03/03/2024] [Indexed: 04/05/2024] Open
Abstract
INTRODUCTION Multiple system atrophy (MSA) is a rapidly progressive neurodegenerative disorder characterized by the presence of glial cytoplasmic inclusions (GCIs) containing aggregated α-synuclein (α-Syn). Accurate diagnosis and monitoring of MSA present significant challenges, which can lead to potential misdiagnosis and inappropriate treatment. Biomarkers play a crucial role in improving the accuracy of MSA diagnosis, and phosphorylated α-synuclein (p-syn) has emerged as a promising biomarker for aiding in diagnosis and disease monitoring. METHODS A literature search was conducted on PubMed, Scopus, and Google Scholar using specific keywords and MeSH terms without imposing a time limit. Inclusion criteria comprised various study designs including experimental studies, case-control studies, and cohort studies published only in English, while conference abstracts and unpublished sources were excluded. RESULTS Increased levels of p-syn have been observed in various samples from MSA patients, such as red blood cells, cerebrospinal fluid, oral mucosal cells, skin, and colon biopsies, highlighting their diagnostic potential. The α-Syn RT-QuIC assay has shown sensitivity in diagnosing MSA and tracking its progression. Meta-analyses and multicenter investigations have confirmed the diagnostic value of p-syn in cerebrospinal fluid, demonstrating high specificity and sensitivity in distinguishing MSA from other neurodegenerative diseases. Moreover, combining p-syn with other biomarkers has further improved the diagnostic accuracy of MSA. CONCLUSION The p-syn stands out as a promising biomarker for MSA. It is found in oligodendrocytes and shows a correlation with disease severity and progression. However, further research and validation studies are necessary to establish p-syn as a reliable biomarker for MSA. If proven, p-syn could significantly contribute to early diagnosis, disease monitoring, and assessing treatment response.
Collapse
Affiliation(s)
| | | | | | | | - Tomas Ferreira
- Department of Clinical Neurosciences, School of Clinical MedicineUniversity of CambridgeCambridgeUK
| | | | | | - Shankhaneel Ghosh
- Institute of Medical Sciences and SUM Hospital, Siksha 'O' AnusandhanBhubaneswarIndia
| | | | - Vandana Garg
- Department of Pharmaceutical SciencesMaharshi Dayanand UniversityRohtakHaryanaIndia
| | - Asma Perveen
- Glocal School of Life SciencesGlocal UniversitySaharanpurUttar PradeshIndia
- Princess Dr. Najla Bint Saud Al‐Saud Center for Excellence Research in BiotechnologyKing Abdulaziz UniversityJeddahSaudi Arabia
| | - Marios Papadakis
- Department of Surgery II, University Hospital Witten‐HerdeckeUniversity of Witten‐HerdeckeWuppertalGermany
| | - Ghulam Md Ashraf
- Department of Medical Laboratory SciencesUniversity of Sharjah, College of Health Sciences, and Research Institute for Medical and Health SciencesSharjahUAE
| | - Athanasios Alexiou
- University Centre for Research & DevelopmentChandigarh UniversityMohaliPunjabIndia
- Department of Research & DevelopmentAthensGreece
- Department of Research & DevelopmentAFNP MedWienAustria
- Department of Science and EngineeringNovel Global Community Educational FoundationNew South WalesAustralia
| |
Collapse
|
3
|
Usman S, Shah MH, Roy S, Ahluwalia A. Breaking silence in the shadows of conflict: ethical challenges and policy imperatives for medical professionals reporting human rights breaches in militarized zones. Med Confl Surviv 2024; 40:44-52. [PMID: 38213005 DOI: 10.1080/13623699.2023.2301193] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Affiliation(s)
- Salim Usman
- School of History, Anthropology, Philosophy and Politics, Queen's University Belfast, Belfast, UK
| | | | - Sakshi Roy
- School of Medicine, Queen's University Belfast, Belfast, UK
| | | |
Collapse
|
4
|
Tan JK, Awuah WA, Roy S, Ferreira T, Ahluwalia A, Guggilapu S, Javed M, Asyura MMAZ, Adebusoye FT, Ramamoorthy K, Paoletti E, Abdul-Rahman T, Prykhodko O, Ovechkin D. Correction to: Exploring the advances of single‑cell RNA sequencing in thyroid cancer: a narrative review. Med Oncol 2024; 41:77. [PMID: 38393647 PMCID: PMC10890972 DOI: 10.1007/s12032-024-02304-w] [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: 02/25/2024]
Affiliation(s)
| | | | - Sakshi Roy
- School of Medicine, Queen's University Belfast, Belfast, UK
| | - Tomas Ferreira
- School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | | | - Saibaba Guggilapu
- Faculty of Medicine, Bangalore Medical College and Research Institute, Bengaluru, India
| | - Mahnoor Javed
- School of Medicine, The University of Nottingham, Nottingham, NG7 2UH, UK
| | | | | | | | - Emma Paoletti
- Faculty of Medicine, University of Manchester, Manchester, M13 9WJ, UK
| | | | - Olha Prykhodko
- Faculty of Medicine, Sumy State University, Sumy, Ukraine
| | - Denys Ovechkin
- Faculty of Medicine, Sumy State University, Sumy, Ukraine
| |
Collapse
|
5
|
Wireko AA, Ahluwalia A, Ali SH, Shah MH, Aderinto N, Banerjee S, Roy S, Ferreira T, Tan JK, Berjaoui C, Guggilapu S, Quarshie LS, Bharadwaj HR, Adebusoye FT, Abdul-Rahman T, Atallah O. Insights into craniosynostosis management in low- and middle-income countries: A narrative review of outcomes, shortcomings and paediatric neurosurgery capacity. SAGE Open Med 2024; 12:20503121241226891. [PMID: 38249946 PMCID: PMC10798110 DOI: 10.1177/20503121241226891] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 12/27/2023] [Indexed: 01/23/2024] Open
Abstract
Craniosynostosis, marked by premature cranial suture fusion, necessitates prompt intervention to avert developmental, neurological, and aesthetic issues. While high-income countries have advanced in managing this condition, low- and middle-income countries grapple with substantial healthcare access disparities. This narrative review explores current craniosynostosis management in low- and middle-income countries. The review focused on studies published between 2008 and 2023. The focus was neurosurgical outcomes, and the search utilised databases like PubMed, EMBASE, Google Scholar, the Cochrane Library and Scopus, incorporating specific keywords and phrases. An in-depth analysis of 21 included studies reveals noteworthy positive outcomes, including low mortality, successful corrections and sustained efficacy. These advancements stem from enhanced pre-operative strategies, surgical techniques and postoperative care. Nonetheless, challenges persist, encompassing complications, mortality, reoperations, and treatment disparities, particularly in low- and middle-income countries constrained by financial and expertise limitations. The enhancement of clinical practice and the formulation of effective policies in the future entail several key strategies. These include the reinforcement of specialised healthcare infrastructure and diagnostic capabilities, the ongoing training and retention of neurosurgeons, the improvement of funding mechanisms, and the promotion of equitable access. Additionally, a crucial focus is placed on fortifying paediatric neurosurgical care in low- and middle-income countries. The recommendations underscore the importance of collaborative initiatives, the development of specialised healthcare infrastructure, and the implementation of strategic policies to not only advance pediatric neurosurgical care but also to address existing gaps in management.
Collapse
Affiliation(s)
| | | | - Syed Hasham Ali
- Faculty of Medicine, Dow Medical College, Dow University of Health Sciences, Karachi, Pakistan
| | | | - Nicholas Aderinto
- Internal Medicine Department, Lautech Teaching Hospital, Ogbomosho, Nigeria
| | | | - Sakshi Roy
- School of Medicine, Queen’s University Belfast, Belfast, UK
| | - Tomas Ferreira
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | | | | | - Saibaba Guggilapu
- Faculty of Medicine, Bangalore Medical College and Research Institute, Bangalore, India
| | | | | | | | | | - Oday Atallah
- Department of Neurosurgery, Hannover Medical School, Hannover, Germany
| |
Collapse
|
6
|
Roy S, Awuah WA, Ahluwalia A, Adebusoye FT, Ferreira T, Tan JK, Bharadwaj HR, Tenkorang PO, Abdul‐Rahman T, Papadakis M. Current trends and challenges: The landscape of perioperative mortality in intracranial surgeries in low- and middle-income settings: A narrative review. Health Sci Rep 2024; 7:e1838. [PMID: 38274132 PMCID: PMC10809023 DOI: 10.1002/hsr2.1838] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 01/09/2024] [Accepted: 01/10/2024] [Indexed: 01/27/2024] Open
Abstract
Background and Aims Intracranial surgeries are pivotal in treating cerebral pathologies, particularly in resource-limited contexts, utilizing techniques such as craniotomy, transsphenoidal approaches, and endoscopy. However, challenges in low and middle income countries (LMICs), including resource scarcity, diagnostic delays, and a lack of skilled neurosurgeons, lead to elevated perioperative mortality (POM). This review seeks to identify major contributors to these challenges and recommend solutions for improved patient outcomes in neurosurgical care within LMICs. Methods This review examines POM in LMICs using a detailed literature search, focusing on studies from these regions. Databases like PubMed, EMBASE, and Google Scholar were utilized using specific terms related to "intracranial surgery," "perioperative mortality," "traumatic brain injuries," and "LMICs." Inclusion criteria covered various study designs and both pediatric and adult populations while excluding stand-alone abstracts and case reports. Results POM rates for intracranial surgeries differ widely across many low and middle-income regions: Africa sees rates from 2.5% to 39.1%, Asia between 3.6% and 34.8%, and Latin America and the Caribbean have figures ranging from 1.3% to 12%. The POM rates in LMICs were relatively higher compared to most first-world countries. The high POM rates in LMICs can be attributed to considerable delays and compromises in neurosurgical care delivery, exacerbated by late diagnoses and presentations of neurosurgical pathologies. This, coupled with limited resources, underdeveloped infrastructure, and training gaps, complicates intracranial disease management, leading to elevated POM. Conclusion Intracranial POM is a pronounced disparity within the neurosurgical field in LMICs. To mitigate intracranial POM, it is imperative to bolster healthcare infrastructure, amplify personnel training, foster global partnerships, and harness technologies like telemedicine. Tackling socioeconomic obstacles and prioritizing early detection through sustained funding and policy shifts can substantially enhance patient outcomes.
Collapse
Affiliation(s)
- Sakshi Roy
- School of MedicineQueen's University BelfastBelfastUK
| | | | | | | | - Tomas Ferreira
- Department of Clinical Neurosciences, School of Clinical MedicineUniversity of CambridgeCambridgeUK
| | | | | | | | | | - Marios Papadakis
- Department of Surgery II, University Hospital Witten‐HerdeckeUniversity of Witten‐HerdeckeWuppertalGermany
| |
Collapse
|
7
|
Tan JK, Awuah WA, Roy S, Ferreira T, Ahluwalia A, Guggilapu S, Javed M, Asyura MMAZ, Adebusoye FT, Ramamoorthy K, Paoletti E, Abdul-Rahman T, Prykhodko O, Ovechkin D. Exploring the advances of single-cell RNA sequencing in thyroid cancer: a narrative review. Med Oncol 2023; 41:27. [PMID: 38129369 PMCID: PMC10739406 DOI: 10.1007/s12032-023-02260-x] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 11/16/2023] [Indexed: 12/23/2023]
Abstract
Thyroid cancer, a prevalent form of endocrine malignancy, has witnessed a substantial increase in occurrence in recent decades. To gain a comprehensive understanding of thyroid cancer at the single-cell level, this narrative review evaluates the applications of single-cell RNA sequencing (scRNA-seq) in thyroid cancer research. ScRNA-seq has revolutionised the identification and characterisation of distinct cell subpopulations, cell-to-cell communications, and receptor interactions, revealing unprecedented heterogeneity and shedding light on novel biomarkers for therapeutic discovery. These findings aid in the construction of predictive models on disease prognosis and therapeutic efficacy. Altogether, scRNA-seq has deepened our understanding of the tumour microenvironment immunologic insights, informing future studies in the development of effective personalised treatment for patients. Challenges and limitations of scRNA-seq, such as technical biases, financial barriers, and ethical concerns, are discussed. Advancements in computational methods, the advent of artificial intelligence (AI), machine learning (ML), and deep learning (DL), and the importance of single-cell data sharing and collaborative efforts are highlighted. Future directions of scRNA-seq in thyroid cancer research include investigating intra-tumoral heterogeneity, integrating with other omics technologies, exploring the non-coding RNA landscape, and studying rare subtypes. Overall, scRNA-seq has transformed thyroid cancer research and holds immense potential for advancing personalised therapies and improving patient outcomes. Efforts to make this technology more accessible and cost-effective will be crucial to ensuring its widespread utilisation in healthcare.
Collapse
Affiliation(s)
| | | | - Sakshi Roy
- School of Medicine, Queen's University Belfast, Belfast, UK
| | - Tomas Ferreira
- School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | | | - Saibaba Guggilapu
- Faculty of Medicine, Bangalore Medical College and Research Institute, Bengaluru, India
| | - Mahnoor Javed
- School of Medicine, The University of Nottingham, Nottingham, NG7 2UH, UK
| | | | | | | | - Emma Paoletti
- Faculty of Medicine, University of Manchester, Manchester, M13 9WJ, UK
| | | | - Olha Prykhodko
- Faculty of Medicine, Sumy State University, Sumy, Ukraine
| | - Denys Ovechkin
- Faculty of Medicine, Sumy State University, Sumy, Ukraine
| |
Collapse
|
8
|
Awuah WA, Ahluwalia A, Ghosh S, Roy S, Tan JK, Adebusoye FT, Ferreira T, Bharadwaj HR, Shet V, Kundu M, Yee ALW, Abdul-Rahman T, Atallah O. The molecular landscape of neurological disorders: insights from single-cell RNA sequencing in neurology and neurosurgery. Eur J Med Res 2023; 28:529. [PMID: 37974227 PMCID: PMC10652629 DOI: 10.1186/s40001-023-01504-w] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 11/03/2023] [Indexed: 11/19/2023] Open
Abstract
Single-cell ribonucleic acid sequencing (scRNA-seq) has emerged as a transformative technology in neurological and neurosurgical research, revolutionising our comprehension of complex neurological disorders. In brain tumours, scRNA-seq has provided valuable insights into cancer heterogeneity, the tumour microenvironment, treatment resistance, and invasion patterns. It has also elucidated the brain tri-lineage cancer hierarchy and addressed limitations of current models. Neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis have been molecularly subtyped, dysregulated pathways have been identified, and potential therapeutic targets have been revealed using scRNA-seq. In epilepsy, scRNA-seq has explored the cellular and molecular heterogeneity underlying the condition, uncovering unique glial subpopulations and dysregulation of the immune system. ScRNA-seq has characterised distinct cellular constituents and responses to spinal cord injury in spinal cord diseases, as well as provided molecular signatures of various cell types and identified interactions involved in vascular remodelling. Furthermore, scRNA-seq has shed light on the molecular complexities of cerebrovascular diseases, such as stroke, providing insights into specific genes, cell-specific expression patterns, and potential therapeutic interventions. This review highlights the potential of scRNA-seq in guiding precision medicine approaches, identifying clinical biomarkers, and facilitating therapeutic discovery. However, challenges related to data analysis, standardisation, sample acquisition, scalability, and cost-effectiveness need to be addressed. Despite these challenges, scRNA-seq has the potential to transform clinical practice in neurological and neurosurgical research by providing personalised insights and improving patient outcomes.
Collapse
Affiliation(s)
- Wireko Andrew Awuah
- Faculty of Medicine, Sumy State University, Zamonstanksya 7, Sumy, 40007, Ukraine
| | | | - Shankaneel Ghosh
- Institute of Medical Sciences and SUM Hospital, Bhubaneswar, India
| | - Sakshi Roy
- School of Medicine, Queen's University Belfast, Belfast, UK
| | | | | | - Tomas Ferreira
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | | | - Vallabh Shet
- Faculty of Medicine, Bangalore Medical College and Research Institute, Bangalore, Karnataka, India
| | - Mrinmoy Kundu
- Institute of Medical Sciences and SUM Hospital, Bhubaneswar, India
| | | | - Toufik Abdul-Rahman
- Faculty of Medicine, Sumy State University, Zamonstanksya 7, Sumy, 40007, Ukraine
| | - Oday Atallah
- Department of Neurosurgery, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| |
Collapse
|
9
|
Massimo G, Khambata RS, Chapman T, Birchall K, Raimondi C, Shabbir A, Dyson N, Rathod K, Borghi C, Ahluwalia A. Corrigendum to "Natural mutations of human XDH promote the nitrite (NO 2-)-reductase capacity of xanthine oxidoreductase: A novel mechanism to promote redox health?" [Redox Biol. 4 (67) (2023) 102864]. Redox Biol 2023; 67:102925. [PMID: 37867029 PMCID: PMC10638451 DOI: 10.1016/j.redox.2023.102925] [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: 10/24/2023] Open
Affiliation(s)
- G Massimo
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - R S Khambata
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - T Chapman
- LifeArc, Accelerator Building Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - K Birchall
- LifeArc, Accelerator Building Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - C Raimondi
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - A Shabbir
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - Nicki Dyson
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - K Rathod
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - C Borghi
- Department of Medical and Surgical Sciences, Faculty of Medicine, University of Bologna, Via Massarenti, N.9, 40138, Italy
| | - A Ahluwalia
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK.
| |
Collapse
|
10
|
Massimo G, Khambata RS, Chapman T, Birchall K, Raimondi C, Shabbir A, Dyson N, Rathod KS, Borghi C, Ahluwalia A. Natural mutations of human XDH promote the nitrite (NO 2-)-reductase capacity of xanthine oxidoreductase: A novel mechanism to promote redox health? Redox Biol 2023; 67:102864. [PMID: 37713777 PMCID: PMC10511815 DOI: 10.1016/j.redox.2023.102864] [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: 08/06/2023] [Revised: 08/24/2023] [Accepted: 08/25/2023] [Indexed: 09/17/2023] Open
Abstract
Several rare genetic variations of human XDH have been shown to alter xanthine oxidoreductase (XOR) activity leading to impaired purine catabolism. However, XOR is a multi-functional enzyme that depending upon the environmental conditions also expresses oxidase activity leading to both O2·- and H2O2 and nitrite (NO2-) reductase activity leading to nitric oxide (·NO). Since these products express important, and often diametrically opposite, biological activity, consideration of the impact of XOR mutations in the context of each aspect of the biochemical activity of the enzyme is needed to determine the potential full impact of these variants. Herein, we show that known naturally occurring hXDH mutations do not have a uniform impact upon the biochemical activity of the enzyme in terms of uric acid (UA), reactive oxygen species (ROS) and nitric oxide ·NO formation. We show that the His1221Arg mutant, in the presence of xanthine, increases UA, O2·- and NO generation compared to the WT, whilst the Ile703Val increases UA and ·NO formation, but not O2·-. We speculate that this change in the balance of activity of the enzyme is likely to endow those carrying these mutations with a harmful or protective influence over health that may explain the current equipoise underlying the perceived importance of XDH mutations. We also show that, in presence of inorganic NO2-, XOR-driven O2·- production is substantially reduced. We suggest that targeting enzyme activity to enhance the NO2--reductase profile in those carrying such mutations may provide novel therapeutic options, particularly in cardiovascular disease.
Collapse
Affiliation(s)
- G Massimo
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - R S Khambata
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - T Chapman
- LifeArc, Accelerator Building Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - K Birchall
- LifeArc, Accelerator Building Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - C Raimondi
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - A Shabbir
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - Nicki Dyson
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - K S Rathod
- William Harvey Research Institute, Barts & the London Faculty of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - C Borghi
- Department of Medical and Surgical Sciences, Faculty of Medicine, University of Bologna, Via Massarenti, N.9, 40138, Italy
| | - A Ahluwalia
- Department of Medical and Surgical Sciences, Faculty of Medicine, University of Bologna, Via Massarenti, N.9, 40138, Italy.
| |
Collapse
|
11
|
Shah MH, Usman S, Roy S, Ahluwalia A, Harky A. Caduceus vs. Rod of Asclepius: A Serpentine Dilemma in Medical Iconography. Postgrad Med J 2023:qgad093. [PMID: 37812829 DOI: 10.1093/postmj/qgad093] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 08/26/2023] [Accepted: 09/13/2023] [Indexed: 10/11/2023]
Abstract
This scholarly inquiry delves into the historical significance of two enduring medical symbols: the Rod of Asclepius and the Caduceus. Tracing their origins back to ancient Greek mythology, we uncover their distinct identities and profound meanings as symbols of healing, unity among medical practitioners, and ethical responsibilities. Beyond aesthetics, these emblems serve as powerful educational tools, fostering universal understanding and connecting modern medicine to its historical heritage. Consequently, embracing their true essence can inspire genuine dedication to the noble mission of caring for others.
Collapse
Affiliation(s)
- Muhammad Hamza Shah
- School of Medicine, Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, BT9 7BL, United Kingdom
- Centre for Anatomy, Deanery of Biomedical Sciences University of Edinburgh, Edinburgh, EH8 9XD, United Kingdom
| | - Salim Usman
- School of History, Anthropology, Philosophy & Politics, Queen's University Belfast, Belfast, BT7 1NN, United Kingdom
| | - Sakshi Roy
- School of Medicine, Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, BT9 7BL, United Kingdom
| | - Arjun Ahluwalia
- School of Medicine, Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, BT9 7BL, United Kingdom
| | - Amer Harky
- Department of Cardiothoracic Surgery, Liverpool Heart & Chest Hospital, Liverpool, L14 3PE, United Kingdom
| |
Collapse
|
12
|
Usman S, Roy S, Ahluwalia A, Shah MH. Dr Ayub Khan Ommaya (1930-2008): The eventful life of a revolutionary neurosurgeon. J Med Biogr 2023:9677720231198502. [PMID: 37722807 DOI: 10.1177/09677720231198502] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
Abstract
Dr Ayub Khan Ommaya (1930-2008) was a pioneering figure in the field of neurosurgery, with a particular focus on traumatic brain injury. As history books have held, he was a man of great intellect and vision, possessing a rare combination of scientific rigour and compassionate empathy. One of Dr Ommaya's most notable contributions was his development of the Ommaya reservoir, a device used to deliver drugs directly into the brain. This groundbreaking technology transformed the treatment of brain tumours and other neurological disorders, enabling clinicians to administer medications with unprecedented precision and efficacy. From his groundbreaking research on traumatic brain injury to his visionary invention of the Ommaya reservoir, Ommaya's legacy continues to inspire and inform the work of countless medical professionals around the world. This historical paper delves into Ommaya's remarkable life story, highlighting his extraordinary contributions to the field of neurosurgery.
Collapse
Affiliation(s)
- Salim Usman
- School of History, Anthropology, Philosophy and Politics, Queen's University Belfast, Belfast, UK
| | - Sakshi Roy
- School of Medicine, Queen's University Belfast, Belfast, UK
| | | | | |
Collapse
|
13
|
Ahluwalia A, Arif A, Shah MH, Roy S. Towards equitable medical education resources: Challenging the representation of ethnicity in clinical vignettes. Med Teach 2023; 45:926. [PMID: 37075239 DOI: 10.1080/0142159x.2023.2200893] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Affiliation(s)
| | - Ashna Arif
- School of Medicine, Queen's University Belfast, Belfast, UK
| | | | - Sakshi Roy
- School of Medicine, Queen's University Belfast, Belfast, UK
| |
Collapse
|
14
|
Roy S, Shah MH, Ahluwalia A, Harky A. Analyzing the Evolution of Medical Ethics Education: A Bibliometric Analysis of the Top 100 Cited Articles. Cureus 2023; 15:e41411. [PMID: 37416085 PMCID: PMC10321571 DOI: 10.7759/cureus.41411] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/05/2023] [Indexed: 07/08/2023] Open
Abstract
Ethics education plays a pivotal role in healthcare by providing professionals and students with the essential competencies to navigate intricate ethical challenges. This study conducts a comprehensive bibliometric analysis of the most-cited articles on ethics education, investigating parameters such as citation count, document types, geographical origin, journal analysis, publication year, author analysis, and keyword usage. The findings reveal a substantial impact characterized by high citation counts and the influence of a prominent publication focusing on the hidden curriculum and structure of medical education. Moreover, the analysis demonstrates a discernible increase in research output since 2000, signaling a growing recognition of the significance of ethics education in the healthcare domain. Notably, specific journals, particularly those dedicated to medical education and ethics, emerge as major contributors in this field, publishing many articles. Renowned authors have made noteworthy contributions, and emerging themes encompass the ethical implications of virtual reality and artificial intelligence in healthcare education. Additionally, undergraduate medical education garners significant attention, emphasizing the importance of establishing ethical values and professionalism early. Overall, this study highlights the imperative of interdisciplinary collaboration and the necessity for effective ethics education programs to equip healthcare professionals with the requisite skills to navigate complex ethical challenges. The findings inform educators, curriculum developers, and policymakers about enhancing ethics education and ensuring the ethical competence of future healthcare practitioners.
Collapse
Affiliation(s)
- Sakshi Roy
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, GBR
| | - Muhammad Hamza Shah
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, GBR
| | - Arjun Ahluwalia
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, GBR
| | - Amer Harky
- Cardiothoracic Surgery, Liverpool Heart and Chest Hospital, Liverpool, GBR
| |
Collapse
|
15
|
Shah MH, Roy S, Ahluwalia A. Time to address the mental health challenges of the South Asian diaspora. Lancet Psychiatry 2023; 10:381-382. [PMID: 37208111 DOI: 10.1016/s2215-0366(23)00144-x] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 04/13/2023] [Accepted: 04/14/2023] [Indexed: 05/21/2023]
Affiliation(s)
| | - Sakshi Roy
- School of Medicine, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Arjun Ahluwalia
- School of Medicine, Queen's University Belfast, Belfast BT9 7BL, UK
| |
Collapse
|
16
|
Shah MH, Roy S, Ahluwalia A, Harky A. #MedEd: Mapping the Current Landscape of Medical Education Discourse and Stakeholder Participation Across Social Media Platforms. Cureus 2023; 15:e39024. [PMID: 37197303 PMCID: PMC10184187 DOI: 10.7759/cureus.39024] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2023] [Indexed: 05/19/2023] Open
Abstract
Background Medical education is a constantly evolving and multifaceted field that requires ongoing discussion and innovation. Social media platforms have emerged as a popular medium for disseminating information and engaging in professional discourse among medical educators. In particular, the hashtag #MedEd has gained widespread recognition amongst individuals and organizations within the medical education community. Our objective is to gain insights into the types of information and discussions surrounding medical education, as well as the individuals or organizations involved in these conversations. Methods Searches were conducted across major social media platforms, including Twitter, Instagram, and Facebook, using the hashtag #MedEd. The top 20 posts posted on these platforms were analyzed through a reflexive thematic analysis approach utilizing the Braun and Clarke method. Furthermore, an examination was conducted on the profiles of those responsible for posting the aforementioned top posts, to ascertain the degree of participation from individuals versus organizations within the broader discourse pertaining to the topic. Results Our analysis revealed three thematic categories associated with the usage of the #MedEd hashtag, including discussions on "continuous learning and medical case presentations," "medical specialties and topics," and "medical education pedagogy." The analysis revealed that social media can serve as a valuable platform for medical education by providing access to a diverse range of learning resources, fostering collaboration and professional networking, and providing innovative teaching methods. Furthermore, profile analysis showed that individuals were more actively involved in the discussion of medical education topics on social media compared to organizations across all three platforms. Conclusion Our study highlights the significant role that social media platforms play in facilitating the exchange of information and ideas within the medical education community. The hashtag #MedEd serves as a means of connecting individuals and organizations across the globe, enabling them to engage in professional discourse and stay informed on the latest developments in the field. Our findings suggest that a better understanding of the thematic categories and stakeholders involved in medical education discussions on social media can aid educators, learners, and organizations in enhancing their engagement with this dynamic field.
Collapse
Affiliation(s)
- Muhammad Hamza Shah
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, GBR
| | - Sakshi Roy
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, GBR
| | - Arjun Ahluwalia
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, GBR
| | - Amer Harky
- Cardiothoracic Surgery, Liverpool Heart and Chest Hospital, Liverpool, GBR
| |
Collapse
|
17
|
Hikin LJ, Ho J, Morley SR, Ahluwalia A, Smith PR. Sodium nitrite poisoning: A series of 20 fatalities in which post-mortem blood nitrite and nitrate concentrations are reported. Forensic Sci Int 2023; 345:111610. [PMID: 36848754 DOI: 10.1016/j.forsciint.2023.111610] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [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: 08/31/2022] [Revised: 02/18/2023] [Accepted: 02/22/2023] [Indexed: 02/27/2023]
Abstract
Sodium nitrite has several industrial applications however its accidental or intentional ingestion has been associated with severe toxicity and death. We present a series of 20 cases over 2 years in which evidence of sodium nitrite ingestion was found at the scene and supported by biochemical analysis of post-mortem blood nitrite and nitrate levels. Routine toxicological screening was performed on post-mortem blood samples received at University Hospitals of Leicester (UHL) NHS Trust, including ethanol analysis by headspace gas chromatography-flame ionisation detection (HS GC-FID), drug screening by high resolution accurate mass-mass spectrometry (HRAM-MS) and confirmatory drug quantitation by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Cases in which the history indicated the possibility of nitrite salts present at the scene, purchase of a suicide kit or a dusky-ash appearance of skin on post-mortem were referred to a specialist laboratory for nitrite and nitrate analysis. Analysis was based upon the gas-phase chemiluminescent reaction between nitric oxide (NO) and ozone; NO levels were determined using an NOA 280A, Sievers NO analyser. Twenty post-mortem cases in which sodium nitrite ingestion was the most probable cause of death were reported between January 2020 and February 2022; mean age was 31 years (range 14-49) with 9/20 (45%) female. 16/20 (80%) of cases had a history of depression and / or mental health issues. In half of the cases, anti-depressant / anti-psychotic drugs were prescribed; these drugs were detected in 8/20 (40%) cases. Ethanol was detected in 4/20 (20%) cases and anti-emetic drugs in 7/20 (35%) cases; anti-emetic drugs may be used to aid retention of sodium nitrite. Illicit drugs (amphetamine, cannabis and cocaine) were present in 3/20 cases (15%). Nitrite was found to be elevated in all but one case (95%), and nitrate was elevated in 17/20 (85%) cases. This paper highlights a surge in numbers of deaths across England and Wales due to sodium nitrite toxicity. Although, nitrite poisoning remains a rare cause of death, it is worthwhile considering its use in individuals with suicidal ideation given its unregulated availability online. The detection and quantitation of nitrite and nitrate requires specialised, highly reliable methodology currently only available in research laboratories. Implication of sodium nitrite ingestion also relies heavily upon circumstantial evidence combined with quantification. The provision of a quantitative nitrite / nitrate analytical service greatly assists in determining the cause of death in these cases.
Collapse
Affiliation(s)
- L J Hikin
- Forensic Toxicology Service, University Hospitals of Leicester NHS Trust, Infirmary Square, Leicester LE1 5WW, UK.
| | - J Ho
- Centre for Cardiovascular Medicines & Devices, William Harvey Research Institute, Barts and The London Faculty of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - S R Morley
- Forensic Toxicology Service, University Hospitals of Leicester NHS Trust, Infirmary Square, Leicester LE1 5WW, UK
| | - A Ahluwalia
- Centre for Cardiovascular Medicines & Devices, William Harvey Research Institute, Barts and The London Faculty of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - P R Smith
- Forensic Toxicology Service, University Hospitals of Leicester NHS Trust, Infirmary Square, Leicester LE1 5WW, UK
| |
Collapse
|
18
|
Hussain SA, Walters S, Ahluwalia A, Trompeter A. Diagnosis and management of arterial injuries associated with limb fracture or dislocation. Br J Hosp Med (Lond) 2022; 83:1-8. [DOI: 10.12968/hmed.2021.0454] [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: 11/11/2022]
Abstract
An arterial injury is a time-critical emergency and, when associated with a fracture or dislocation, its management requires joint specialist input from orthopaedic and vascular or plastic surgeons. Initial management involves haemorrhage control and stabilisation of the patient, reduction and splinting of the limb and careful reassessment. With ongoing vascular compromise, urgent surgery is indicated to restore arterial flow and stabilise the skeleton, and this should be performed at a centre with appropriate expertise. This article provides an evidence-based review of the British Orthopaedic Association Standards for Trauma for the diagnosis and management of arterial injuries associated with extremity fractures and dislocations.
Collapse
Affiliation(s)
- SA Hussain
- Department of Trauma and Orthopaedic Surgery, Croydon University Hospital, London, UK
| | - S Walters
- Department of Trauma and Orthopaedic Surgery, Croydon University Hospital, London, UK
| | - A Ahluwalia
- Department of Trauma and Orthopaedic Surgery, University College Hospital, London, UK
| | - A Trompeter
- Orthopaedic Trauma/Limb Reconstruction Unit, St George's University Hospital, London, UK
| |
Collapse
|
19
|
Lau C, Shabbir A, Rathod KS, Chhetri I, Ono M, Hamers AJP, Amarin JJ, Ibrahim A, Nuredini G, Godec T, Kapil V, Ahluwalia A. Inorganic nitrate attenuates endothelial dysfunction consequent to systemic inflammation. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.3008] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
Chronic cardiovascular diseases are characterised by low-grade systemic inflammation and attenuated nitric oxide (NO) bioavailability resulting in endothelial dysfunction. Inorganic nitrate augments NO bioavailability and improves markers of vascular dysfunction in patients with cardiovascular risk factors. However, the exact mechanism of this effect is uncertain.
Purpose
To determine whether inorganic nitrate supplementation alters systemic inflammation-induced endothelial dysfunction.
Methods
62 healthy male volunteers were randomised 1:1 to receive ∼8–10 mmol of dietary inorganic nitrate in beetroot juice or nitrate-free beetroot juice (placebo) once daily for 6 days. Measures of brachial artery flow-mediated dilatation (FMD), brachial blood pressure (BP), pulse wave analysis and carotid-femoral pulse wave velocity (PWV) by Vicorder were taken prior to and at 8 hours after a typhoid vaccine (to induce mild systemic inflammation). Plasma, urine and saliva samples were also collected. Clinicaltrials.gov: NCT02715635.
Results
Baseline characteristics were similar between the two groups. Inorganic nitrate significantly elevated plasma nitrite (placebo = Δ0.02±0.5 μM, inorganic nitrate = Δ0.63±1.2 μM; p=0.01) and nitrate levels (p<0.0001) compared to placebo. There were significant increases in urine nitrite (p<0.0001) and nitrate (p<0.0001) in addition to salivary nitrite (p<0.0001) and nitrate (p<0.0001) compared to placebo. After 8 hours, typhoid vaccine induced an increase in circulating white cells (placebo = Δ3.34±3.37x109/L, inorganic nitrate = Δ2.9±2.78x109/L; p=0.58) that was similar in in both arms. However, there was a significant reduction in the FMD response in the placebo group at 8-hours post vaccine; an effect that was absent in volunteers treated with inorganic nitrate (placebo = Δ−1.33±1.53%, inorganic nitrate = Δ−0.07±1.84%, p=0.005). Importantly, there were no statistically significant differences in baseline vessel diameter (p=0.78), time to peak diameter in response to flow (p=0.87) and peak shear rate (p=0.57) between the groups. When comparing change from baseline to 8 hours after the vaccine, there were no significant differences in brachial systolic BP (p=0.12), central systolic BP (p=0.12) and PWV (p=0.60) between groups, but a significant reduction in brachial diastolic BP in the inorganic nitrate group (p=0.048).
Conclusions
Inflammation-induced endothelial dysfunction was prevented in those receiving dietary inorganic nitrate suggesting that elevating circulating nitrite and delivering NO to the blood vessel wall, through dietary approaches may offer potential therapeutic benefit in those cardiovascular diseases which typically exhibit low grade inflammation and deficiencies in bioavailable NO.
Funding Acknowledgement
Type of funding sources: Public Institution(s). Main funding source(s): British Heart Foundation
Collapse
Affiliation(s)
- C Lau
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - A Shabbir
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - K S Rathod
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - I Chhetri
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - M Ono
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - A J P Hamers
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - J J Amarin
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - A Ibrahim
- University of Southampton, Southampton, United Kingdom
| | - G Nuredini
- Barts Health NHS Trust, London, United Kingdom
| | - T Godec
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - V Kapil
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - A Ahluwalia
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| |
Collapse
|
20
|
Primus C, Masucci M, Whitear C, Montalvo Moreira SA, Ajit Kumar N, Chhetri I, Rathod KS, Khambata R, Kapil V, Ahluwalia A. A pro-resolving phenotype underpins the anti-inflammatory effects of inorganic nitrate. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.3352] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
Increasing evidence highlights the critical role of chronic inflammation in cardiovascular disease (CVD). Targeting inflammatory pathways in patients with CVD has been associated with improved CV function in pre-clinical (Gee, 2017), early clinical (Yndestad, 2006; Velmurugan 2013; Jones, 2016) and large phase III studies (Ridker, 2017).
The resolution of inflammation is an active process and its failure has also been proposed to contribute to CVD progression. At least one mechanism thought to underlie this failure is dysfunction of the canonical pathway for anti-inflammatory nitric oxide (NO) production. Restoring NO through provision of inorganic nitrate (NO3-) and subsequent bioactivation via the non-canonical pathway may offer therapeutic benefit.
Aim
To test whether dietary NO3–derived NO accelerates resolution of inflammation.
Methods
Randomised, double-blind, placebo-controlled, parallel limb study of 8–10mmol dietary NO3- supplementation versus NO3–deplete placebo beetroot juice in 36 healthy male volunteers (NCT03183830). Using a cantharadin-induced skin blister model (Day, 2001), acute (24h) and chronic (72h)-phase blisters were harvested pre- and post-treatment. Blister exudate was analysed for leucocyte activation state (CD11b, CD62L, CD162) by flow cytometry and cytokine/chemokine composition by ELISA. Ozone chemiluminescence established NO3-/NO2- levels in key biological matrices: plasma, urine and saliva.
Results
9.3mmol inorganic NO3- led to a significant rise (versus placebo, p<0.001) of NO3-/NO2- in plasma, saliva and urine NO2- (p<0.02). No differences were seen in blister volumes, cell counts or markers of systemic inflammation. Whilst no differences were seen in the proportions of cellular infiltrate in 24h blisters, there were significant reductions of neutrophil (p=0.017) and intermediate monocyte proportions (p=0.001) and cellular adhesion molecules across inflammatory, intermediate and resolving monocytes at 72h (Figure 1). Generally, no differences in blister cytokine/chemokine profile was evident except for borderline significant suppression of TNFα at 24hrs with dietary NO3- treatment (P=0.057).
Conclusion
Whilst dietary inorganic NO3- does not impair the essential host defence response it does accelerate resolution: enhanced pro- to anti-inflammatory monocyte subtype switching and curtailed neutrophil recruitment, likely via attenuated TNFα production. These actions offer a novel, easy to administer, approach to influence inflammatory responses without impairing host defence.
Funding Acknowledgement
Type of funding sources: Public Institution(s). Main funding source(s): Derek Willoughby Trust and British Heart Foundation
Collapse
Affiliation(s)
- C Primus
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| | - M Masucci
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| | - C Whitear
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| | - S A Montalvo Moreira
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| | - N Ajit Kumar
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| | - I Chhetri
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| | - K S Rathod
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| | - R Khambata
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| | - V Kapil
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| | - A Ahluwalia
- Queen Mary University of London, William Harvey Research Institute, London, United Kingdom
| |
Collapse
|
21
|
Shabbir A, Lau C, Rathod KS, Chhetri I, Haque A, Godec T, Khambata RS, Kapil V, Ahluwalia A. Inorganic nitrate attenuates the systemic inflammatory response in typhoid vaccine-induced endothelial dysfunction in healthy volunteers. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.3009] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Inflammatory responses underlie the development of endothelial dysfunction in CVD, however, therapeutics that might target this pathway have not been forthcoming. A key pathogenic mechanism mediating endothelial dysfunction is a reduction in bioavailable (eNOS-derived) nitric oxide (NO). Activation of the non-canonical pathway for in-vivo NO generation might offer an approach to improve NO levels and recover vascular function in pre-clinical models of CVD. Whether this might occur in humans is unknown.
Purpose
We hypothesize that consumption of inorganic nitrate will lead to increases in bioavailable NO and thus attenuate the inflammatory pathways leading to typhoid vaccine-induced endothelial dysfunction in healthy volunteers.
Methods
Healthy male volunteers were recruited (n=78) and randomized to receive either beetroot juice containing 8–10mmol nitrate or placebo (nitrate-deplete) juice once daily for 6 days. Participants underwent serial measurements of BP, FMD and GTN-induced brachial artery dilatation, and haematology and biochemistry, before and after typhoid vaccination. Blood, urine and saliva nitrite and nitrate were quantified using ozone chemiluminescence, and leukocyte flow cytometry analysis was conducted.
Results
8-hours post-vaccine endothelial function was depressed in placebo-treated volunteers, however this was prevented in nitrate-treated volunteers. This dysfunction was due to impaired endothelial function since responses to GTN were unaffected either by vaccination or dietary intervention (p=0.981). Dietary nitrate resulted in an increase in plasma (p<0.0001), urine (p=0.0006) and saliva (p<0.0001) nitrate, and urine (p=0.0354) and saliva (p<0.0001) nitrite levels. There was a reduction in the proportions of CD14++/CD16+intermediate monocytes in nitrate-treated participants after vaccine (p=0.016, change from baseline between groups). In the nitrate-treated group, less CD14++/CD16+ intermediate monocyte CD62L expression was identified post-vaccine (p=0.0122), compared to placebo, with no difference in soluble plasma CD62L between groups (p=0.875). CD11b median fluorescence intensity was increased in CD3+/CD4+ T-lymphocytes in nitrate-treated volunteers (p=0.0095).
Conclusions
Dietary nitrate reduced BP, as previously shown, indicating efficacy of the intervention. Importantly, we also now show for the first time that inorganic nitrate suppresses the systemic inflammatory response, specifically by reducing the numbers and activation state of CD14++/CD16+ intermediate monocytes. Furthermore, an increased expression of CD3+/CD4+ T-cell CD11b and preserved FMD in healthy volunteers treated with nitrate, suggests an anti-inflammatory phenotype, induced by the intervention, leading to improved endothelial function. Inorganic dietary nitrate modulates endothelial function through the attenuation of inflammatory responses and may be of potential therapeutic benefit in patients with established CAD.
Funding Acknowledgement
Type of funding sources: None.
Collapse
Affiliation(s)
- A Shabbir
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - C Lau
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - K S Rathod
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - I Chhetri
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - A Haque
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - T Godec
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - R S Khambata
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - V Kapil
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - A Ahluwalia
- St Bartholomews and Queen Mary University, London, United Kingdom
| |
Collapse
|
22
|
Affiliation(s)
- K Saggar
- Department of Radiodiagnosis, Dyanand Medical College & Hospital, Ludhiana - 141001, India
| | - A Ahluwalia
- Department of Radiodiagnosis, Dyanand Medical College & Hospital, Ludhiana - 141001, India
| | - P Sandhu
- Department of Radiodiagnosis, Dyanand Medical College & Hospital, Ludhiana - 141001, India
| | - V Kalia
- Department of Radiodiagnosis, Dyanand Medical College & Hospital, Ludhiana - 141001, India
| |
Collapse
|
23
|
Kapil V, Khambata RS, Jones DA, Rathod K, Primus C, Massimo G, Fukuto JM, Ahluwalia A. The Noncanonical Pathway for In Vivo Nitric Oxide Generation: The Nitrate-Nitrite-Nitric Oxide Pathway. Pharmacol Rev 2020; 72:692-766. [DOI: 10.1124/pr.120.019240] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
|
24
|
Ingram JR, Ahluwalia A. The pharmacology of itch. Br J Pharmacol 2019; 176:4419-4420. [PMID: 31612462 DOI: 10.1111/bph.14865] [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: 11/27/2022] Open
Abstract
The article has been co-published with permission in British Journal of Dermatology and British Journal of Pharmacology. The articles are identical except for minor stylistic and spelling differences in keeping with each journal's style. Either citation can be used when citing this article.
Collapse
Affiliation(s)
- J R Ingram
- Division of Infection & Immunity, Cardiff University, Cardiff, UK
| | - A Ahluwalia
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| |
Collapse
|
25
|
Ingram JR, Ahluwalia A. The pharmacology of itch. Br J Dermatol 2019; 184:e1-e2. [PMID: 31578709 DOI: 10.1111/bjd.18525] [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: 11/27/2022]
Affiliation(s)
- J R Ingram
- Division of Infection & Immunity, Cardiff University, Cardiff, U.K
| | - A Ahluwalia
- William Harvey Research Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London, U.K
| |
Collapse
|
26
|
Cacopardo L, Costa J, Giusti S, Buoncompagni L, Meucci S, Corti A, Mattei G, Ahluwalia A. Real-time cellular impedance monitoring and imaging of biological barriers in a dual-flow membrane bioreactor. Biosens Bioelectron 2019; 140:111340. [PMID: 31154254 DOI: 10.1016/j.bios.2019.111340] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 12/18/2022]
Abstract
The generation of physiologically relevant in-vitro models of biological barriers can play a key role in understanding human diseases and in the development of more predictive methods for assessing toxicity and drug or nutrient absorption. Here, we present an advanced cell culture system able to mimic the dynamic environment of biological barriers while monitoring cell behaviour through real-time impedance measurements and imaging. It consists of a fluidic device with an apical and a basal flow compartment separated by a semi-permeable membrane. The main features of the device are the integration of sensing through transepithelial electrical impedance (TEEI) measurements and transparent windows for optical monitoring within a dual flow system. Caco-2 cells were cultured in the TEEI bioreactor under both flow and static conditions. Although no differences in the expression of peripheral actin and occludin were visible, the cells in dynamic conditions developed higher impedance values at low frequencies, indicative of a higher paracellular electrical impedance with respect to the static cultures. TEEI measurements at high frequency also enabled monitoring monolayer formation, which can be correlated with the observation of an RC behaviour in the impedance spectra. In particular, the cells subject to flow showed accelerated barrier formation and increased vitality with respect to the static controls, again highlighting the importance of dynamic conditions for epithelial cells.
Collapse
Affiliation(s)
- L Cacopardo
- Research Centre 'E. Piaggio', University of Pisa, Italy; Department of Information Engineering, University of Pisa, Italy
| | - J Costa
- Research Centre 'E. Piaggio', University of Pisa, Italy; Department of Information Engineering, University of Pisa, Italy
| | - S Giusti
- Research Centre 'E. Piaggio', University of Pisa, Italy; IVTech S.r.l, Pisa, Italy
| | | | - S Meucci
- Micronit Microtechnologies, Enschede, the Netherlands
| | - A Corti
- Research Centre 'E. Piaggio', University of Pisa, Italy; Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Italy
| | - G Mattei
- Department of Information Engineering, University of Pisa, Italy
| | - A Ahluwalia
- Research Centre 'E. Piaggio', University of Pisa, Italy; Department of Information Engineering, University of Pisa, Italy.
| |
Collapse
|
27
|
Jones DA, Whittaker P, Rathod KS, Richards AJ, Andiapen M, Antoniou S, Mathur A, Ahluwalia A. P2564Sodium nitrite-mediated cardioprotection in primary percutaneous coronary intervention for ST-elevation myocardial infarction: a cost-effectiveness analysis. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy565.p2564] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- D A Jones
- Barts Health NHS Trust, London, United Kingdom
| | - P Whittaker
- Wayne State University, Detroit, United States of America
| | - K S Rathod
- Barts Health NHS Trust, London, United Kingdom
| | | | - M Andiapen
- Barts Health NHS Trust, London, United Kingdom
| | - S Antoniou
- Barts Health NHS Trust, London, United Kingdom
| | - A Mathur
- Barts Health NHS Trust, London, United Kingdom
| | - A Ahluwalia
- Queen Mary University of London, London, United Kingdom
| |
Collapse
|
28
|
Ahluwalia A, Jones MK, Brzozowska I, Tarnawski AS. In vitro model of vasculo-angiogenesis: demonstration that bone marrow derived endothelial progenitor cells form new hybrid capillary blood vessels jointly with gastric endothelial cells. J Physiol Pharmacol 2017; 68:841-846. [PMID: 29550796] [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] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 11/20/2017] [Indexed: 02/06/2023]
Abstract
Regeneration of blood vessels (neovascularization) is critical for tissue injury healing. The contribution of bone marrow-derived endothelial progenitor cells (BMD-EPCs) to neovascularization during tissue injury healing is not fully elucidated and it is not clear whether BMD-EPCs can form new capillary blood vessels independently or jointly with fully differentiated endothelial cells (ECs). The aim of this study was to establish an in vitro model of vasculogenesis/angiogenesis by co-culture of BMD-EPCs and gastric endothelial cells (GECs) on Matrigel, examine direct interactions of these cells; and, identify the mechanisms involved. We isolated BMD-EPCs and GECs from bone marrow and stomach of rats, respectively. In these cells, we examined the expression of CD34, CD133, CD31, VEGF-R2, stromal derived factor 1 (SDF-1) and CXCR4, and, their ability to form capillary-like tubes when cultured separately or when co-cultured (1:5 ratio) on growth factor-reduced Matrigel. Fluorescence-labeled BMD-EPCs seeded alone on Matrigel formed capillary-like tubes reflecting in vitro vasculogenesis, and when co-cultured with GECs on Matrigel, formed 'hybrid' tubes containing BMD-EPCs nested between GECs thus reflecting in vitro angio-vasculogenesis. These 'hybrid' tubes were 1.5-fold wider (P < 0.001) and had more extensive (5.1-fold increase) loops (P < 0.01) at the junctions of BMD-EPCs and GECs versus tubes formed by GECs alone. GECs expressed SDF-1 that likely mediated homing of BMD-EPCs (which expressed the SDF-1 receptor, CXCR4) and their incorporation during neovascularization. BMD-EPCs can independently form capillary-like tubes on Matrigel, and when co-cultured with fully differentiated ECs on Matrigel, form capillary-like 'hybrid' tubes comprised of both cell types. Both BMD-EPCs and GECs express SDF-1 and CXCR4, which indicate direct paracrine interactions between these cells during neovascularization.
Collapse
Affiliation(s)
- A Ahluwalia
- Medical and Research Services, Veterans Affairs Medical Center, Long Beach, CA, USA
| | - M K Jones
- Medical and Research Services, Veterans Affairs Medical Center, Long Beach, CA, USA
- Department of Medicine, University of California, Irvine, CA, USA
| | - I Brzozowska
- Department of Anatomy, Jagiellonian University Medical College, Cracow, Poland
| | - A S Tarnawski
- Medical and Research Services, Veterans Affairs Medical Center, Long Beach, CA, USA. ;
- Department of Medicine, University of California, Irvine, CA, USA
| |
Collapse
|
29
|
Ahluwalia A, Brzozowski T, Jones MK, Ichikawa Y, Tarnawski AS. Formation of new blood vessels during gastric ulcer healing. Role of bone marrow derived endothelial progenitor cells. J Physiol Pharmacol 2017; 68:585-589. [PMID: 29151075] [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] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 08/21/2017] [Indexed: 02/06/2023]
Abstract
Regeneration of blood vessels (neovascularization) is critical for gastric ulcer (GU) healing. The contributions of bone marrow-derived endothelial progenitor cells (BMD-EPCs) to neovascularization during GU healing are not fully elucidated. Our specific aims were to determine whether in GU, BMD-EPCs are incorporated into blood vessels of GU granulation tissue jointly with ECs, thus forming hybrid vessels; or, form separate vessels consisting of only BMD-EPCs. GUs were induced in rats by serosal application of acetic acid. Vascular cast studies were performed at 7, 21 and 60 days after GU induction and tissue specimens were immunostained for CD34, CD133, VEGFR2, and SDF-1 at 14 days. Human relevance was determined using archival human GU specimens. In rat GU granulation tissue BMD-EPCs constituted 28 ± 3% of all cells lining newly formed blood vessels, and were nested between fully differentiated ECs. In rat GU granulation tissue, expression of stromal derived factor-1 (SDF-1) - the major chemoattractant for BMD-EPCs was strongly upregulated. In human GU specimens, BMD-EPCs were also present in granulation tissue constituting 34 ± 3% of all cells lining blood vessels and jointly formed hybrid vessels with differentiated ECs. Our study uncovered that BMD-EPCs incorporate into newly formed blood vessels in GU granulation tissue; and, together with ECs of pre-existing vessels, contribute to and support neovascularization through vasculogenesis. This study is the first demonstration that vasculogenesis occurs during GU healing in both humans and in rats.
Collapse
Affiliation(s)
- A Ahluwalia
- Medical and Research Services, Veterans Affairs Medical Center, Long Beach, California, USA
| | - T Brzozowski
- Department of Physiology, Jagiellonian University Medical College, Cracow, Poland
| | - M K Jones
- Medical and Research Services, Veterans Affairs Medical Center, Long Beach, California, USA
- Department of Medicine, University of California, Irvine, CA, USA
| | - Y Ichikawa
- Department of Oncology, Yokohama City University, Graduate School of Medicine,Yokohama, Japan
| | - A S Tarnawski
- Medical and Research Services, Veterans Affairs Medical Center, Long Beach, California, USA. ;
- Department of Medicine, University of California, Irvine, CA, USA
| |
Collapse
|
30
|
Lissel A, Ottenberg F, Bracio BR, Ravizza A, De Maria C, Ahluwalia A, Di Pietro L, Trommler P. Status and solutions to medical device regulations for improving the healthcare landscape in Africa. Annu Int Conf IEEE Eng Med Biol Soc 2017; 2016:4329-4332. [PMID: 28269236 DOI: 10.1109/embc.2016.7591685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
For different reasons most African countries have a poor public healthcare system compared to developed countries. Despite an increasing number of patients they often lack skilled health workers as well as basic medical equipment. This paper focuses on the development of an affordable and sustainable system for medical device regulations to provide safe, effective and quality healthcare products for Africa. Furthermore, it is determined whether Open Source Medical Devices are an effective alternative for medical device regulations to increase innovations in Africa.
Collapse
|
31
|
Ali T, McCabe A, Ahluwalia A, Fairburn K, Racey M, Jutley G. Predicting temporal artery biopsy results … offering insights into temporal arteritis. Int J Oral Maxillofac Surg 2017. [DOI: 10.1016/j.ijom.2017.02.1150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
32
|
Tarnawski AS, Ahluwalia A, Jones MK, Brzozowski T. Expression of nerve growth factor in rat stomach. Implications for interactions between endothelial, neural and epithelial cells. J Physiol Pharmacol 2016; 67:879-883. [PMID: 28195068] [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] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 12/22/2016] [Indexed: 02/06/2023]
Abstract
UNLABELLED This study was aimed to determine the expression and localization of nerve growth factor (NGF) in the gastric mucosa. Transmural gastric specimens were obtained from euthanized rats. STUDIES 1) expression of NGF and TrkA receptor by Western blotting; 2) histological evaluation of gastric wall architecture; 3) expression of NGF using immunostaining. Immunostaining showed strong and differential expression of NGF in neural elements of gastric myenteric and submucosal plexuses; in epithelial cells: mainly in chief and progenitor cells, in enterochromaffin-like (ECL) cells; and, in endothelial cells (ECs) lining blood vessels. We concluded that NGF expression in neural elements, epithelial cells and endothelial cells of blood vessels indicated a complex local interaction between neural, epithelial and endothelial cells that regulated gastric mucosal homeostasis and, likely, the protection against gastric injury and ulcer healing.
Collapse
Affiliation(s)
- A S Tarnawski
- Medical and Research Services, Veterans Affairs Long Beach Healthcare System (VALBHS), Long Beach, California, USA.
- Department of Medicine, University of California, Irvine, California, USA
| | - A Ahluwalia
- Medical and Research Services, Veterans Affairs Long Beach Healthcare System (VALBHS), Long Beach, California, USA
| | - M K Jones
- Medical and Research Services, Veterans Affairs Long Beach Healthcare System (VALBHS), Long Beach, California, USA
- Department of Medicine, University of California, Irvine, California, USA
| | - T Brzozowski
- Department of Physiology, Jagiellonian University Medical College, Cracow, Poland
| |
Collapse
|
33
|
Tanigawa T, Ahluwalia A, Watanabe T, Arakawa T, Tarnawski AS. Nerve growth factor injected into the gastric ulcer base incorporates into endothelial, neuronal, glial and epithelial cells: implications for angiogenesis, mucosal regeneration and ulcer healing. J Physiol Pharmacol 2015; 66:617-21. [PMID: 26348086] [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] [Received: 03/05/2015] [Accepted: 07/20/2015] [Indexed: 02/06/2023]
Abstract
A previous study has demonstrated that locally administered growth factors such as epidermal growth factor, basic fibroblast growth factor and hepatocyte growth factor can accelerate healing of experimental gastric ulcers in rats. That study indicates that locally administered growth factors can exert potent biological effects resulting in enhanced gastric ulcers healing. However, the fate of injected growth factors, their retention and localization to specific cellular compartments have not been examined. In our preliminary study, we demonstrated that local injection of nerve growth factor to the base of experimental gastric ulcers dramatically accelerates ulcer healing, increases angiogenesis - new blood vessel formation, and improves the quality of vascular and epithelial regeneration. Before embarking on larger, definitive and time sequence studies, we wished to determine whether locally injected nerve growth factor is retained in gastric ulcer's tissues and taken up by specific cells during gastric ulcer healing. Gastric ulcers were induced in anesthetized rats by local application of acetic acid using standard methods; and, 60 min later fluorescein isothiocyanate-labeled nerve growth factor was injected locally to the ulcer base. Rats were euthanized 2, 5 and 10 days later. Gastric specimens were obtained and processed for histology. Unstained paraffin sections were examined under a fluorescence microscope, and the incorporation of fluorescein isothiocyanate-labeled nerve growth factor into various gastric tissue cells was determined and quantified. In addition, we performed immunostaining for S100β protein that is expressed in neural components. Five and ten days after ulcer induction labeled nerve growth factor (injected to the gastric ulcer base) was incorporated into endothelial cells of blood vessels, neuronal, glial and epithelial cells, myofibroblasts and muscle cells. This study demonstrates for the first time that during gastric ulcer healing locally administered exogenous nerve growth factor is retained in gastric tissue and is taken up by endothelial, neural, muscle and epithelial cells. This is likely the basis for the therapeutic action of locally administered nerve growth factor and its stimulation of angiogenesis, tissue regeneration and gastric ulcer healing.
Collapse
Affiliation(s)
- T Tanigawa
- Department of Medicine, Long Beach Veterans Affairs Healthcare System, Long Beach, California and the University of California-Irvine, CA, USA
- Department of Gastroenterology, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - A Ahluwalia
- Department of Medicine, Long Beach Veterans Affairs Healthcare System, Long Beach, California and the University of California-Irvine, CA, USA
| | - T Watanabe
- Department of Gastroenterology, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - T Arakawa
- Department of Gastroenterology, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - A S Tarnawski
- Department of Medicine, Long Beach Veterans Affairs Healthcare System, Long Beach, California and the University of California-Irvine, CA, USA.
| |
Collapse
|
34
|
Mattei G, Gruca G, Rijnveld N, Ahluwalia A. The nano-epsilon dot method for strain rate viscoelastic characterisation of soft biomaterials by spherical nano-indentation. J Mech Behav Biomed Mater 2015; 50:150-9. [PMID: 26143307 DOI: 10.1016/j.jmbbm.2015.06.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [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: 05/26/2015] [Revised: 06/12/2015] [Accepted: 06/15/2015] [Indexed: 11/16/2022]
Abstract
Nano-indentation is widely used for probing the micromechanical properties of materials. Based on the indentation of surfaces using probes with a well-defined geometry, the elastic and viscoelastic constants of materials can be determined by relating indenter geometry and measured load and displacement to parameters which represent stress and deformation. Here we describe a method to derive the viscoelastic properties of soft hydrated materials at the micro-scale using constant strain rates and stress-free initial conditions. Using a new self-consistent definition of indentation stress and strain and corresponding unique depth-independent expression for indentation strain rate, the epsilon dot method, which is suitable for bulk compression testing, is transformed to nano-indentation. We demonstrate how two materials can be tested with a displacement controlled commercial nano-indentor using the nano-espilon dot method (nano-ε̇M) to give values of instantaneous and equilibrium elastic moduli and time constants with high precision. As samples are tested in stress-free initial conditions, the nano-ε̇M could be useful for characterising the micro-mechanical behaviour of soft materials such as hydrogels and biological tissues at cell length scales.
Collapse
Affiliation(s)
- G Mattei
- Research Centre "E. Piaggio", University of Pisa, Largo Lucio Lazzarino 1, 56122 Pisa, Italy
| | - G Gruca
- Optics11, De Boelelaan 108, 1081 HV Amsterdam, The Netherlands
| | - N Rijnveld
- Optics11, De Boelelaan 108, 1081 HV Amsterdam, The Netherlands
| | - A Ahluwalia
- Research Centre "E. Piaggio", University of Pisa, Largo Lucio Lazzarino 1, 56122 Pisa, Italy.
| |
Collapse
|
35
|
Samarasena JB, Ahluwalia A, Tarnawski AS, Shinoura S, Choi KD, Lee JG, Chang KJ. Expression of nerve growth factor, its TrkA receptor, and several neuropeptides in porcine esophagus. Implications for interactions between neural, vascular and epithelial components of the esophagus. J Physiol Pharmacol 2015; 66:415-20. [PMID: 26084223] [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] [Received: 03/20/2015] [Accepted: 04/16/2015] [Indexed: 02/06/2023]
Abstract
UNLABELLED This study was aimed to determine the expression and localization of nerve growth factor (NGF) and several neural peptides in porcine esophagus. Transmural esophageal specimens were obtained from euthanized pigs. STUDIES 1) histologic evaluation, 2) expressions of NGF and its tropomyosin receptor kinase A (TrkA) receptor, calcitonin generelated peptide (CGRP), neuronal nitric oxide synthase (nNOS), and neuronal enolase using immunostaining and quantification of signal distribution and intensity. Immunostaining for NGF, CGRP, nNOS and neuronal specific enolase (NSE) showed their strong and differential expression and localization in the neuronal network. NGF was strongly expressed in the majority of neurons and nerves, distribution of TrkA was complementary; its signal was 1.5-fold weaker P < 0.001 than NGF). Quantitatively the signal intensity was: CGRP > nNOS > NGF > NES > TrkA. In addition to neural structures, nNOS, NGF and TrkA were expressed in keratinocyte progenitor cells of esophageal mucosa and in endothelial cells of blood vessels. We conclude that a strong expression of NGF in majority of esophageal neurons and nerves indicates important, but previously unrecognized regulatory roles in the esophagus; 2) This study showed expression of NGF and some of the neuropeptides in neural elements, keratinocyte progenitor cells and endothelial cells of blood vessels, which indicates local interactions between neural, epithelial and endothelial cells.
Collapse
Affiliation(s)
- J B Samarasena
- Division of Gastroenterology and Hepatology, Department of Medicine, University of California - Irvine, Orange, California, USA
| | - A Ahluwalia
- Division of Gastroenterology, Department of Medicine, Long Beach Veterans Affairs Healthcare System, Long Beach, California, USA
| | - A S Tarnawski
- Division of Gastroenterology and Hepatology, Department of Medicine, University of California - Irvine, Orange, California, USA
- Division of Gastroenterology, Department of Medicine, Long Beach Veterans Affairs Healthcare System, Long Beach, California, USA
| | - S Shinoura
- Division of Gastroenterology and Hepatology, Department of Medicine, University of California - Irvine, Orange, California, USA
| | - K D Choi
- Division of Gastroenterology and Hepatology, Department of Medicine, University of California - Irvine, Orange, California, USA
| | - J G Lee
- Division of Gastroenterology and Hepatology, Department of Medicine, University of California - Irvine, Orange, California, USA
| | - K J Chang
- Division of Gastroenterology and Hepatology, Department of Medicine, University of California - Irvine, Orange, California, USA.
| |
Collapse
|
36
|
Mattei G, Cristiani I, Magliaro C, Ahluwalia A. Profile analysis of hepatic porcine and murine brain tissue slices obtained with a vibratome. PeerJ 2015; 3:e932. [PMID: 25945319 PMCID: PMC4419543 DOI: 10.7717/peerj.932] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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: 10/27/2014] [Accepted: 04/14/2015] [Indexed: 11/28/2022] Open
Abstract
This study is aimed at characterizing soft tissue slices using a vibratome. In particular, the effect of two sectioning parameters (i.e., step size and sectioning speed) on resultant slice thickness was investigated for fresh porcine liver as well as for paraformaldehyde-fixed (PFA-fixed) and fresh murine brain. A simple framework for embedding, sectioning and imaging the slices was established to derive their thickness, which was evaluated through a purposely developed graphical user interface. Sectioning speed and step size had little effect on the thickness of fresh liver slices. Conversely, the thickness of PFA-fixed murine brain slices was found to be dependent on the step size, but not on the sectioning speed. In view of these results, fresh brain tissue was sliced varying the step size only, which was found to have a significant effect on resultant slice thickness. Although precision-cut slices (i.e., with regular thickness) were obtained for all the tissues, slice accuracy (defined as the match between the nominal step size chosen and the actual slice thickness obtained) was found to increase with tissue stiffness from fresh liver to PFA-fixed brain. This quantitative investigation can be very helpful for establishing the most suitable slicing setup for a given tissue.
Collapse
Affiliation(s)
- G Mattei
- Research Center "E. Piaggio," University of Pisa , Pisa , Italy
| | - I Cristiani
- Research Center "E. Piaggio," University of Pisa , Pisa , Italy
| | - C Magliaro
- Research Center "E. Piaggio," University of Pisa , Pisa , Italy
| | - A Ahluwalia
- Research Center "E. Piaggio," University of Pisa , Pisa , Italy ; Institute of Clinical Physiology, National Research Council , Pisa , Italy
| |
Collapse
|
37
|
Lara J, Ashor AW, Oggioni C, Ahluwalia A, Mathers JC, Siervo M. Effects of inorganic nitrate and beetroot supplementation on endothelial function: a systematic review and meta-analysis. Eur J Nutr 2015; 55:451-459. [DOI: 10.1007/s00394-015-0872-7] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 03/02/2015] [Indexed: 01/19/2023]
|
38
|
Tirella A, Magliaro C, Penta M, Troncone M, Pimentel R, Ahluwalia A. Sphyga: a multiparameter open source tool for fabricating smart and tunable hydrogel microbeads. Biofabrication 2014; 6:025009. [PMID: 24694569 DOI: 10.1088/1758-5082/6/2/025009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Hydrogel microbeads are used in many biological applications, particularly for cell, protein or drug encapsulation. Although there are several methods for fabricating microbeads with controlled shapes and dimensions, many are limited to a small range of materials or sizes. We describe a compact open source tool-the spherical hydrogel generator (Sphyga)-for the fabrication of highly reproducible hydrogel based microbeads with predictable shapes and diameters ranging from 100 to 2000 µm. The unique feature of the system is the ability to modulate multiple parameters independently, so as to create a wide range of working conditions for fabricating tailored microbeads. Hence, by combining the different fabrication parameters, hydrogel beads with chosen shapes, sizes and materials can be generated with Sphyga. A multiparameter working-window was obtained by fixing the concentration of the base material, alginate, and varying the viscosity of the solution along with Sphyga's fabrication parameters (needle size, external air pressure, and material outflow). To validate the multiparameter working window, components such as proteins, cells, dyes and nanoparticles were also used to fabricate composite microbeads. The results show that the architecture of hydrogel microbeads can be engineered by considering the viscosity of the initial solution, which depends principally on the pH and composition of alginate solution. Coupled with Sphyga's multiple working parameters, material viscosity can then be used to tune hydrogel domains and thereby generate complex biologically relevant microenvironments for many biomedical applications.
Collapse
Affiliation(s)
- A Tirella
- Institute of Clinical Physiology (IFC), National Research Council (CNR), Via Moruzzi 1, I-56124, Italy. Research Center 'E Piaggio', University of Pisa, Research Center '"E. Piaggio'", Largo Lazzarino 1, I-56122, Italy
| | | | | | | | | | | |
Collapse
|
39
|
Ahluwalia A, Jones MK, Szabo S, Tarnawski AS. Aging impairs transcriptional regulation of vascular endothelial growth factor in human microvascular endothelial cells: implications for angiogenesis and cell survival. J Physiol Pharmacol 2014; 65:209-15. [PMID: 24781730] [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] [Received: 02/05/2014] [Accepted: 04/03/2014] [Indexed: 02/06/2023]
Abstract
In some tissues, aging impairs angiogenesis and reduces expression of vascular endothelial growth factor A (VEGF), a fundamental regulator of angiogenesis. We previously examined angiogenesis in aging and young gastric mucosa in vivo and in vitro and showed that an imbalance between expressions of VEGF (pro-angiogenic factor) and endostatin (anti-angiogenic protein) results in an aging-related impairment of angiogenesis in rats. However, the human relevance of these findings, and whether these mechanisms apply to endothelial cells derived from other tissues, is not clear. Since P-STAT3 and P-CREB are transcription factors that, in association with HIF-1α, can activate VEGF gene expression in some cells (e.g., liver cancer cells, vascular smooth muscle cells), we examined the expression of these two proteins in human dermal microvascular endothelial cells (HMVECs) derived from aging and neonatal individuals. We examined and quantified in vitro angiogenesis, expression of VEGF, P-STAT3, P-CREB and importin-α in HMVECs isolated from neonates (neonatal) and a 66 year old subject (aging). We also examined the effects of treatment with exogenous VEGF and endostatin on in vitro angiogenesis in these cells. Endothelial cells isolated from aging individuals had impaired angiogenesis (vs. neonatal endothelial cells) and reduced expression of VEGF mRNA and protein. Aged HMVECs also had reduced importin-α expression, and reduced expression and nuclear translocation of P-STAT3 and P-CREB. Reduced VEGF gene expression in aged HMVECs strongly correlated with the decreased levels of P-STAT3, P-CREB and importin-α in these cells. Our study clearly demonstrates that endothelial cells from aging individuals have impaired angiogenesis and reduced expression of VEGF likely due to impaired nuclear transport of P-STAT3 and P-CREB transcription factors in these cells.
Collapse
Affiliation(s)
- A Ahluwalia
- Veterans Affairs Long Beach Healthcare System, Long Beach, CA, USA.
| | | | | | | |
Collapse
|
40
|
Tirella A, Mattei G, Ahluwalia A. Strain rate viscoelastic analysis of soft and highly hydrated biomaterials. J Biomed Mater Res A 2013; 102:3352-60. [PMID: 23946054 PMCID: PMC4304325 DOI: 10.1002/jbm.a.34914] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 07/26/2013] [Accepted: 08/05/2013] [Indexed: 11/07/2022]
Abstract
Measuring the viscoelastic behavior of highly hydrated biological materials is challenging because of their intrinsic softness and labile nature. In these materials, it is difficult to avoid prestress and therefore to establish precise initial stress and strain conditions for lumped parameter estimation using creep or stress-relaxation (SR) tests. We describe a method ( ɛ˙M or epsilon dot method) for deriving the viscoelastic parameters of soft hydrated biomaterials which avoids prestress and can be used to rapidly test degradable samples. Standard mechanical tests are first performed compressing samples using different strain rates. The dataset obtained is then analyzed to mathematically derive the material's viscoelastic parameters. In this work a stable elastomer, polydimethylsiloxane, and a labile hydrogel, gelatin, were first tested using the ɛ˙M, in parallel SR was used to compare lumped parameter estimation. After demonstrating that the elastic parameters are equivalent and that the estimation of short-time constants is more precise using the proposed method, the viscoelastic behavior of porcine liver was investigated using this approach. The results show that the constitutive parameters of hepatic tissue can be quickly quantified without the application of any prestress and before the onset of time-dependent degradation phenomena.
Collapse
Affiliation(s)
- A Tirella
- Research Centre "E. Piaggio", University of Pisa, Via Diotisalvi 2, 56124, Pisa, Italy; National Research Council, IFC, Via Moruzzi 1, 56122, Pisa, Italy
| | | | | |
Collapse
|
41
|
|
42
|
Jones DA, Andiapen M, Van-Eijl TJA, Webb AJ, Antoniou S, Schilling RJ, Ahluwalia A, Mathur A. The safety and efficacy of intracoronary nitrite infusion during acute myocardial infarction (NITRITE-AMI): study protocol of a randomised controlled trial. BMJ Open 2013; 3:bmjopen-2013-002813. [PMID: 23550096 PMCID: PMC3641434 DOI: 10.1136/bmjopen-2013-002813] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
INTRODUCTION Acute myocardial infarction (AMI) is a major cause of death and disability in the UK and worldwide. Presently, timely and effective reperfusion with primary percutaneous coronary intervention (PPCI) remains the most effective treatment strategy for limiting infarct size, preserving left ventricular ejection fraction (LVEF) and improving clinical outcomes. However, the process of reperfusion can itself induce cardiomyocyte death, known as myocardial reperfusion injury, for which there is currently no effective therapy. Extensive preclinical evidence exists to suggest that sodium nitrite (as a source of endogenous nitric oxide) is an effective therapeutic strategy for preventing myocardial reperfusion injury. The purpose of NITRITE-AMI is to test whether sodium nitrite reduces reperfusion injury and subsequent infarct size in patients undergoing PPCI for MI. METHODS AND DESIGN NITRITE-AMI is a double-blind, randomised, single-centre, placebo-controlled trial to determine whether intracoronary nitrite injection reduces infarct size in patients with myocardial infarction undergoing primary angioplasty. The study will enrol 80 patients presenting with ST-elevation myocardial infarction. Patients will be randomised to receive either a bolus of intracoronary sodium nitrite or placebo (sodium chloride) at the time of PPCI. The primary outcome is infarct size assessed by creatine kinase area under the curve (AUC) over 48 h. Secondary endpoints include troponin T AUC and infarct size, LV dimensions and myocardial salvage index assessed by cardiac MR (CMR), markers of platelet reactivity and inflammation, the safety and tolerability of intracoronary nitrite, and 1 year major adverse cardiac events. ETHICS AND DISSEMINATION The study is approved by the local ethics committee (NRES Committee London West London: 11/LO/1500) and by the Medicines and Healthcare Products Regulatory Agency (MHRA) (EudraCT nr. 2010-022460-12). The results of the trial will be published according to the CONSORT statement and will be presented at conferences and reported in peer-reviewed journals. TRIAL REGISTRATION United Kingdom Clinical Research Network (Study ID 12117), http://clinicaltrials.gov (NCT01584453) and Current Controlled Trials (ISRCTN:38736987).
Collapse
Affiliation(s)
- D A Jones
- Centre of Clinical Pharmacology, Barts NIHR Cardiovascular Biomedical Research Unit, William Harvey Research Institute, Queen Mary University, London, UK
- Department of Cardiology, London Chest Hospital, Barts Health NHS Trust, London, UK
| | - M Andiapen
- Department of Cardiology, London Chest Hospital, Barts Health NHS Trust, London, UK
| | - T J A Van-Eijl
- Centre of Clinical Pharmacology, Barts NIHR Cardiovascular Biomedical Research Unit, William Harvey Research Institute, Queen Mary University, London, UK
| | - A J Webb
- Centre of Clinical Pharmacology, Barts NIHR Cardiovascular Biomedical Research Unit, William Harvey Research Institute, Queen Mary University, London, UK
| | - S Antoniou
- Department of Cardiology, London Chest Hospital, Barts Health NHS Trust, London, UK
| | - R J Schilling
- Centre of Clinical Pharmacology, Barts NIHR Cardiovascular Biomedical Research Unit, William Harvey Research Institute, Queen Mary University, London, UK
- Department of Cardiology, London Chest Hospital, Barts Health NHS Trust, London, UK
| | - A Ahluwalia
- Centre of Clinical Pharmacology, Barts NIHR Cardiovascular Biomedical Research Unit, William Harvey Research Institute, Queen Mary University, London, UK
| | - A Mathur
- Centre of Clinical Pharmacology, Barts NIHR Cardiovascular Biomedical Research Unit, William Harvey Research Institute, Queen Mary University, London, UK
- Department of Cardiology, London Chest Hospital, Barts Health NHS Trust, London, UK
| |
Collapse
|
43
|
Giusti S, Pagliari F, Vozzi F, Tirella A, Mazzei D, Cabiati M, Del Ry S, Ahluwalia A. SQPR 3.0: A Sensorized Bioreactor for Modulating Cardiac Phenotype. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.proeng.2013.05.114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
44
|
Nakai Y, Shinoura S, Ahluwalia A, Tarnawski AS, Chang KJ. In vivo visualization of epidermal growth factor receptor and survivin expression in porcine pancreas using endoscopic ultrasound guided fine needle imaging with confocal laser-induced endomicroscopy. J Physiol Pharmacol 2012; 63:577-80. [PMID: 23388473] [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] [Received: 10/29/2012] [Accepted: 12/03/2012] [Indexed: 02/06/2023]
Abstract
UNLABELLED The aims of this pilot study were to establish a principle of molecular imaging of the pancreas and determine in vivo expression of epidermal growth factor receptor (EGF-R) and survivin using a novel endoscopic ultrasound-guided fine needle imaging (EUS-FNI) technique, which incorporates needle based confocal laser-induced endomicroscopy (nCLE) after intrapancreatic injection of FTIC-labeled antibodies. Studies were performed in anesthetized pigs. FITC-labeled specific antibodies against EGF-R and survivin were injected into the tail and neck of the pancreas using a 19 gauge needle introduced under EUS guidance. Thirty minutes later, nCLE was performed using a prototype needle-based confocal laser-induced endomicroscopy probe (Cellvizio AQ-Flex-19, Mauna Kea Technologies, Paris, France) to determine cellular and tissue localization of EGF-R and survivin in the pancreas. Then pigs were euthanized and specimens of pancreas from areas injected with antibodies were obtained for histologic examination under epifluorescence microscope. RESULTS EUS-guided nCLE enabled visualization of EGF-R and survivin in pancreatic tissue. Expression of EGF-R and survivin in pancreas was confirmed by histology. EGF-R immunoreactivity was localized to majority of duct-lining cells and to the surface and cytoplasm of many acinar cells. Survivin was localized mainly to the acinar cells. This study demonstrated the feasibility of in vivo, real time visualization of EGF-R and survivin in the pancreas by local injection of FITC-labeled antibodies via EUS-guided fine needle injection, followed by EUS-guided needle based confocal laser-induced endomicroscopy.
Collapse
Affiliation(s)
- Y Nakai
- Division of Gastroenterology and Hepatology, H.H. Chao Comprehensive Digestive Disease Center, University of California, Irvine School of Medicine, CA, USA
| | | | | | | | | |
Collapse
|
45
|
Nakai Y, Shinoura S, Ahluwalia A, Tarnawski AS, Chang KJ. Molecular imaging of epidermal growth factor-receptor and survivin in vivo in porcine esophageal and gastric mucosae using probe-based confocal laser-induced endomicroscopy: proof of concept. J Physiol Pharmacol 2012; 63:303-7. [PMID: 22791645] [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] [Received: 05/10/2012] [Accepted: 06/20/2012] [Indexed: 02/06/2023]
Abstract
UNLABELLED Confocal laser-induced endomicroscopy (CLE) enables in vivo, real time visualization of the subsurface cells and tissue structures in gastrointestinal mucosa at a subcellular resolution of ≈1000x magnification. The aims of this pilot study were to establish a principle of molecular imaging and determine in vivo expression of epidermal growth factor receptor (EGF-R) and survivin in porcine esophageal and gastric mucosa using probe-based CLE (pCLE) and topically applied FITC-labeled antibodies. Studies were performed in anesthetized pigs. During endoscopy FITC-labeled antibodies against EGF-R and survivin were either sprayed onto esophageal and gastric mucosa in preselected areas or administered via submucosal injection. Thirty minutes later pCLE was performed using a through-the-scope probe (GastroFlex UHD, Cellvizio, Mauna Kea Technologies, Paris, France) to determine cellular and tissue localization of EGF-R and survivin. Then the pigs were euthanized and esophageal and gastric walls from the areas sprayed or injected with antibodies were collected for histologic examination under epifluorescence microscopy. RESULTS CLE enabled visualization of EGF-R and survivin in esophageal and gastric mucosa and this was confirmed by histology. In the esophagus both EGF-R and survivin were localized predominantly to the keratinocyte progenitor cells. In the stomach, EGF-R was localized to progenitor zone cells and some epithelial cells. Localization of survivin was similar, but involved more surface epithelial cells. This study demonstrated feasibility of using CLE and topical administration of FITC labeled antibodies for in vivo localization of EGF-R and survivin in esophageal and gastric mucosa.
Collapse
Affiliation(s)
- Y Nakai
- Division of Gastroenterology and Hepatology, H.H. Chao Comprehensive Digestive Disease Center, University of California, Irvine, School of Medicine, CA, USA
| | | | | | | | | |
Collapse
|
46
|
Bianchi F, Vassalle C, Simonetti M, Vozzi G, Domenici C, Ahluwalia A. Endothelial cell function on 2D and 3D micro-fabricated polymer scaffolds: applications in cardiovascular tissue engineering. Journal of Biomaterials Science, Polymer Edition 2012; 17:37-51. [PMID: 16411597 DOI: 10.1163/156856206774879117] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Polymeric structures of a polylactide-polycaprolactone blend were micro-fabricated using the Pressure Assisted Microsyringe (PAM) system. Human umbilical vein endothelial cells were cultured on the scaffolds, and apoptosis, cell adhesion, proliferation and metabolism were evaluated. In addition, more specific indicators of endothelial cell function, namely nitric oxide and endothelin production, were also assessed. Thin films of the blend, as well as gelatine-coated glass slides (as controls) were used. The results show that as far as adhesion, apoptosis and metabolism are concerned, the scaffolds do not interfere with cell function compared with gelatin controls. However, the nitric oxide/endothelin ratio was higher than that observed on the gelatin films, suggesting that the scaffolds could be used for engineering small diameter blood vessels without risk of occlusion.
Collapse
Affiliation(s)
- F Bianchi
- Interdepartmental Research Center E Piaggio, Faculty of Engineering, University of Pisa, Italy
| | | | | | | | | | | |
Collapse
|
47
|
Perez-Pomares JM, Ruiz-Villalba A, Ziogas A, Segovia JC, Ehrbar M, Munoz-Chapuli R, De La Rosa A, Dominguez JN, Hove-Madsen L, Sankova B, Sedmera D, Franco D, Aranega Jimenez A, Babaeva G, Chizh N, Galchenko S, Sandomirsky B, Schwarzl M, Seiler S, Steendijk P, Huber S, Maechler H, Truschnig-Wilders M, Pieske B, Post H, Simrick S, Kreutzer R, Rao C, Terracciano CM, Kirchhof P, Fabritz L, Brand T, Theveniau-Ruissy M, Parisot P, Francou A, Saint-Michel E, Mesbah K, Kelly RG, Wu HT, Sie SS, Chen CY, Kuan TC, Lin CS, Ismailoglu Z, Guven M, Yakici A, Ata Y, Ozcan S, Yildirim E, Ongen Z, Miroshnikova V, Demina E, Rodygina T, Kurjanov P, Denisenko A, Schwarzman A, Rubanenko A, Shchukin Y, Germanov A, Goldbergova M, Parenica J, Lipkova J, Pavek N, Kala P, Poloczek M, Vasku A, Parenicova I, Spinar J, Gambacciani C, Chiavacci E, Evangelista M, Vesentini N, Kusmic C, Pitto L, Chernova A, Nikulina SUY, Arvanitis DA, Mourouzis I, Pantos C, Kranias EG, Cokkinos DV, Sanoudou D, Vladimirskaya TE, Shved IA, Kryvorot SG, Schirmer IM, Appukuttan A, Pott L, Jaquet K, Ladilov Y, Archer CR, Bootman MD, Roderick HL, Fusco A, Sorriento D, Santulli G, Trimarco B, Iaccarino G, Hagenmueller M, Riffel J, Gatzoulis MA, Stoupel EG, Garcia R, Merino D, Montalvo C, Hurle MA, Nistal JF, Villar AV, Perez-Moreno A, Gilabert R, Bernhold E, Ros E, Amat-Roldan I, Katus HA, Hardt SE, Maqsood A, Zi M, Prehar S, Neyses L, Ray S, Oceandy D, Khatami N, Wadowski P, Wagh V, Hescheler J, Sachinidis A, Mohl W, Chaudhry B, Burns D, Henderson DJ, Bax NAM, Van Marion MH, Shah B, Goumans MJ, Bouten CVC, Van Der Schaft DWJ, Bax NAM, Van Oorschot AAM, Maas S, Braun J, Van Tuyn J, De Vries AAF, Gittenberger-De Groot AC, Goumans MJ, Bageghni S, Drinkhill MJ, Batten TFC, Ainscough JFX, Onate B, Vilahur G, Ferrer-Lorente R, Ybarra J, Diez-Caballero A, Ballesta-Lopez C, Moscatiello F, Herrero J, Badimon L, Martin-Rendon E, Clifford DM, Fisher SA, Brusnkill SJ, Doree C, Mathur A, Clarke M, Watt SM, Hernandez-Vera R, Badimon L, Kavanagh D, Yemm AI, Frampton J, Kalia N, Terajima Y, Shimizu T, Tsuruyama S, Ishii H, Sekine H, Hagiwara N, Okano T, Vrijsen KR, Chamuleau SAJ, Sluijter JPG, Doevendans PFM, Madonna R, Delli Pizzi S, Di Donato L, Mariotti A, Di Carlo L, D'ugo E, Teberino MA, Merla A, T A, De Caterina R, Kolker L, Ali NN, Maclellan K, Moore M, Wheeler J, Harding SE, Fleck RA, Rowlinson JM, Kraenkel N, Ascione R, Madeddu P, O'sullivan JF, Leblond AL, Kelly G, Kumar AHS, Metharom P, Buneker CK, Alizadeh-Vikali N, Hynes BG, O'connor R, Caplice NM, Noseda M, De Smith AJ, Leja T, Rao PH, Al-Beidh F, Abreu Pavia MS, Blakemore AI, Schneider MD, Stathopoulou K, Cuello F, Ehler E, Haworth RS, Avkiran M, Morawietz H, Eickholt C, Langbein H, Brux M, Goettsch C, Goettsch W, Arsov A, Brunssen C, Mazilu L, Parepa IR, Suceveanu AI, Suceveanu AP, De Man FS, Guignabert C, Tu L, Handoko ML, Schalij I, Fadel E, Postmus PE, Vonk-Noordegraaf A, Humbert M, Eddahibi S, Sorriento D, Santulli G, Del Giudice C, Anastasio A, Trimarco B, Iaccarino G, Fazal L, Azibani F, Bihry N, Merval R, Polidano E, Samuel JL, Delcayre C, Zhang Y, Mi YM, Ren LL, Cheng YP, Guo R, Liu Y, Jiang YN, Mourouzis I, Pantos C, Kokkinos AD, Cokkinos DV, Tretjakovs P, Jurka A, Bormane I, Mikelsone I, Reihmane D, Elksne K, Krievina G, Verbovenko J, Bahs G, Lopez-Andres N, Rousseau A, Calvier L, Akhtar R, Labat C, Cruickshank K, Diez J, Zannad F, Lacolley P, Rossignol P, Hamesch K, Subramanian P, Li X, Thiemann A, Heyll K, Dembowsky K, Chevalier E, Weber C, Schober A, Yang L, Kim G, Gardner B, Earley J, Hofmann-Bowman M, Cheng CF, Lian WS, Lin H, Jinjolia NJ, Abuladze GA, Tvalchrelidze SHT, Khamnagadaev I, Shkolnikova M, Kokov L, Miklashevich I, Drozdov I, Ilyich I, Bingen BO, Askar SFA, Ypey DL, Van Der Laarse A, Schalij MJ, Pijnappels DA, Roney CH, Ng FS, Chowdhury RA, Chang ETY, Patel PM, Lyon AR, Siggers JH, Peters NS, Obergrussberger A, Stoelzle S, Bruggemann A, Haarmann C, George M, Fertig N, Moreira D, Souza A, Valente P, Kornej J, Reihardt C, Kosiuk J, Arya A, Hindricks G, Adams V, Husser D, Bollmann A, Camelliti P, Dudhia J, Dias P, Cartledge J, Connolly DJ, Terracciano CM, Nobles M, Sebastian S, Tinker A, Opel A, Tinker A, Daimi H, Haj Khelil A, Be Chibani J, Barana A, Amoros I, Gonzalez De La Fuente M, Caballero R, Aranega A, Franco D, Kelly A, Bernus O, Kemi OJ, Myles RC, Ghouri IA, Burton FL, Smith GL, Del Lungo M, Sartiani L, Spinelli V, Baruscotti M, Difrancesco D, Mugelli A, Cerbai E, Thomas AM, Aziz Q, Khambra T, Tinker A, Addlestone JMA, Cartwright EJ, Wilkinson R, Song W, Marston S, Jacquet A, Mougenot NM, Lipskaia AJ, Paalberends ER, Stam K, Van Dijk SJ, Van Slegtenhorst M, Dos Remedios C, Ten Cate FJ, Michels M, Niessen HWM, Stienen GJM, Van Der Velden J, Read MI, Andreianova AA, Harrison JC, Goulton CS, Kerr DS, Sammut IA, Schwarzl M, Seiler S, Wallner M, Huber S, Steendijk P, Maechler H, Truschnig-Wilders M, Von Lewinski D, Pieske B, Post H, Kindsvater D, Saes M, Morano I, Muegge A, Jaquet K, Buyandelger B, Kostin S, Gunkel S, Vouffo J, Ng K, Chen J, Eilers M, Isaacson R, Milting H, Knoell R, Cattin ME, Crocini C, Schlossarek S, Maron S, Hansen A, Eschenhagen T, Carrier L, Bonne G, Coppini R, Ferrantini C, Olivotto I, Del Lungo M, Belardinelli L, Poggesi C, Mugelli A, Cerbai E, Leung MC, Messer AE, Copeland O, Marston SB, Mills AM, Collins T, O'gara P, Thum T, Regalla K, Lyon AR, Macleod KT, Harding SE, Rao C, Prodromakis T, Chaudhry U, Darzi A, Yacoub MH, Athanasiou T, Terracciano CM, Bogdanova A, Makhro A, Hoydal M, Stolen TO, Johnssen AB, Alves M, Catalucci D, Condorelli G, Koch LG, Britton SL, Smith GL, Wisloff U, Bito V, Claus P, Vermeulen K, Huysmans C, Ventura-Clapier R, Sipido KR, Seliuk MN, Burlaka AP, Sidorik EP, Khaitovych NV, Kozachok MM, Potaskalova VS, Driesen RB, Galan DT, Vermeulen K, Claus P, Sipido KR, De Paulis D, Arnoux T, Schaller S, Pruss RM, Poitz DM, Augstein A, Braun-Dullaeus RC, Schmeisser A, Strasser RH, Micova P, Balkova P, Hlavackova M, Zurmanova J, Kasparova D, Kolar F, Neckar J, Novak F, Novakova O, Pollard S, Babba M, Hussain A, James R, Maddock H, Alshehri AS, Baxter GF, Dietel B, Altendorf R, Daniel WG, Kollmar R, Garlichs CD, Sirohi R, Roberts N, Lawrence D, Sheikh A, Kolvekar S, Yap J, Arend M, Walkinshaw G, Hausenloy DJ, Yellon DM, Posa A, Szabo R, Szalai Z, Szablics P, Berko MA, Orban K, Murlasits ZS, Balogh L, Varga C, Ku HC, Su MJ, Chreih RM, Ginghina C, Deleanu D, Ferreira ALBJ, Belal A, Ali MA, Fan X, Holt A, Campbell R, Schulz R, Bonanad C, Bodi V, Sanchis J, Morales JM, Marrachelli V, Nunez J, Forteza MJ, Chaustre F, Gomez C, Chorro FJ, Csont T, Fekete V, Murlasits Z, Aypar E, Bencsik P, Sarkozy M, Varga ZV, Ferdinandy P, Duerr GD, Zoerlein M, Dewald D, Mesenholl B, Schneider P, Ghanem A, Rittling S, Welz A, Dewald O, Duerr GD, Dewald D, Becker E, Peigney C, Ghanem A, Welz A, Dewald O, Bouleti C, Galaup A, Monnot C, Ghaleh B, Germain S, Timmermans A, Ginion A, De Meester C, Sakamoto K, Vanoverschelde JL, Horman S, Beauloye C, Bertrand L, Maroz-Vadalazhskaya N, Drozd E, Kukharenko L, Russkich I, Krachak D, Seljun Y, Ostrovski Y, Martin AC, Le Bonniec B, Lecompte T, Dizier B, Emmerich J, Fischer AM, Samama CM, Godier A, Mogensen S, Furchtbauer EM, Aalkjaer C, Choong WL, Jovanovic A, Khan F, Daniel JM, Dutzmann JM, Widmer-Teske R, Guenduez D, Sedding D, Castro MM, Cena JJC, Cho WJC, Goobie GG, Walsh MPW, Schulz RS, Daniel JM, Dutzmann J, Widmer-Teske R, Preissner KT, Sedding D, Aziz Q, Khambra T, Sones W, Thomas AM, Kotlikoff M, Tinker A, Serizawa K, Yogo K, Aizawa K, Hirata M, Tashiro Y, Ishizuka N, Varela A, Katsiboulas M, Tousoulis D, Papaioannou TG, Vaina S, Davos CH, Piperi C, Stefanadis C, Basdra EK, Papavassiliou AG, Hermenegildo C, Lazaro-Franco M, Sobrino A, Bueno-Beti C, Martinez-Gil N, Walther T, Peiro C, Sanchez-Ferrer CF, Novella S, Ciccarelli M, Franco A, Sorriento D, Del Giudice C, Dorn GW, Trimarco B, Iaccarino G, Cseplo P, Torok O, Springo ZS, Vamos Z, Kosa D, Hamar J, Koller A, Bubb KJ, Ahluwalia A, Stepien EL, Gruca A, Grzybowska J, Goralska J, Dembinska-Kiec A, Stepien EL, Stolinski J, Grzybowska J, Goralska J, Partyka L, Gruca A, Dembinska-Kiec A, Zhang H, Sweeney D, Thomas GN, Fish PV, Taggart DP, Watt SM, Martin-Rendon E, Cioffi S, Bilio M, Martucciello S, Illingworth E, Caporali A, Shantikumar S, Marchetti M, Martelli F, Emanueli C, Marchetti M, Meloni M, Caporali A, Al Haj Zen A, Sala-Newby G, Emanueli C, Del Turco S, Saponaro C, Dario B, Sartini S, Menciassi A, Dario P, La Motta C, Basta G, Santiemma V, Bertone C, Rossi F, Michelon E, Bianco MJ, Castelli A, Shin DI, Seung KB, Seo SM, Park HJ, Kim PJ, Baek SH, Shin DI, Seung KB, Seo SM, Park HJ, Choi YS, Her SH, Kim DB, Kim PJ, Lee JM, Park CS, Rocchiccioli S, Cecchettini A, Pelosi G, Kusmic C, Citti L, Parodi O, Trivella MG, Michel-Monigadon D, Burger F, Dunoyer-Geindre S, Pelli G, Cravatt B, Steffens S, Didangelos A, Mayr U, Yin X, Stegemann C, Shalhoub J, Davies AH, Monaco C, Mayr M, Lypovetska S, Grytsenko S, Njerve IU, Pettersen AA, Opstad TB, Bratseth V, Arnesen H, Seljeflot I, Dumitriu IE, Baruah P, Antunes RF, Kaski JC, Forteza MJ, Bodi V, Trapero I, Benet I, Alguero C, Chaustre FJ, Gomez C, Sanchis J, Chorro FJ, Mangold A, Puthenkalam S, Distelmaier K, Adlbrecht C, Preissner KT, Lang IM, Koizumi T, Inoue I, Komiyama N, Nishimura S, Korneeva ON, Drapkina OM, Fornai L, Angelini A, Kiss A, Giskes F, Eijkel G, Fedrigo M, Valente ML, Thiene G, Heeren RMA, Vilahur G, Padro T, Casani L, Suades R, Badimon L, Bertoni B, Carminati R, Carlini V, Pettinari L, Martinelli C, Gagliano N, Noppe G, Buchlin P, Marquet N, Baeyens N, Morel N, Vanoverschelde JL, Bertrand L, Beauloye C, Horman S, Baysa A, Sagave J, Dahl CP, Gullestad L, Carpi A, Di Lisa F, Giorgio M, Vaage J, Valen G, Vafiadaki E, Papalouka V, Arvanitis DA, Terzis G, Spengos K, Kranias EG, Manta P, Sanoudou D, Gales C, Genet G, Dague E, Cazorla O, Payre B, Mias C, Ouille A, Lacampagne A, Pathak A, Senard JM, Abonnenc M, Da Costa Martins P, Srivastava S, Didangelos A, Yin X, Gautel M, De Windt L, Mayr M, Comelli L, Rocchiccioli S, Lande C, Ucciferri N, Trivella MG, Citti L, Cecchettini A, Ikonen L, Vuorenpaa H, Kujala K, Sarkanen JR, Heinonen T, Ylikomi T, Aalto-Setala K, Capros H, Sprincean N, Usurelu N, Egorov V, Stratu N, Matchkov V, Bouzinova E, Moeller-Nielsen N, Wiborg O, Aalkjaer C, Gutierrez PS, Aparecida-Silva R, Borges LF, Moreira LFP, Dias RR, Kalil J, Stolf NAG, Zhou W, Suntharalingam K, Brand N, Vilar Compte R, Ying L, Bicknell K, Dannoura A, Dash P, Brooks G, Tsimafeyeu I, Tishova Y, Wynn N, Oyeyipo IP, Olatunji LA, Maegdefessel L, Azuma J, Toh R, Raaz U, Merk DR, Deng A, Spin JM, Tsao PS, Lande C, Cecchettini A, Tedeschi L, Taranta M, Naldi I, Citti L, Trivella MG, Grimaldi S, Cinti C, Bousquenaud M, Maskali F, Poussier S, Marie PY, Boutley H, Karcher G, Wagner DR, Devaux Y, Torre I, Psilodimitrakopoulos S, Iruretagoiena I, Gonzalez-Tendero A, Artigas D, Loza-Alvarez P, Gratacos E, Amat-Roldan I, Murray L, Carberry DM, Dunton P, Miles MJ, Suleiman MS, Kanesalingam K, Taylor R, Mc Collum CN, Parniczky A, Solymar M, Porpaczy A, Miseta A, Lenkey ZS, Szabados S, Cziraki A, Garai J, Koller A, Myloslavska I, Menazza SM, Canton MC, Di Lisa FDL, Schulz RS, Oliveira SHV, Morais CAS, Miranda MR, Oliveira TT, Lamego MRA, Lima LM, Goncharova NS, Naymushin AV, Kazimli AV, Moiseeva OM, Lima LM, Carvalho MG, Sabino AP, Mota APL, Sousa MO, Niessner A, Richter B, Hohensinner PJ, Rychli K, Zorn G, Berger R, Moertl D, Pacher R, Wojta J, Huelsmann M, Kukharchik G, Nesterova N, Pavlova A, Gaykovaya L, Krapivka N, Konstantinova I, Sichinava L, Prapa S, Mccarthy KP, Kilner PJ, Xu XY, Johnson MR, Ho SY. Poster session 2. Cardiovasc Res 2012. [DOI: 10.1093/cvr/cvr334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
48
|
Coron E, Mosnier JF, Ahluwalia A, Le Rhun M, Galmiche JP, Tarnawski AS, Matysiak-Budnik T. Colonic mucosal biopsies obtained during confocal endomicroscopy are pre-stained with fluorescein in vivo and are suitable for histologic evaluation. Endoscopy 2012; 44:148-53. [PMID: 22271025 DOI: 10.1055/s-0031-1291534] [Citation(s) in RCA: 6] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND STUDY AIMS Confocal laser endomicroscopy (CLE) with intravenous infusion of fluorescein allows noninvasive, real-time in vivo visualization of gastrointestinal mucosa at ~ × 1000 magnification ("virtual biopsy"). Conventional biopsies obtained during these procedures serve as the reference and established diagnostic standard. The aim of the present study was to assess whether the standard histologic biopsies that are obtained during CLE retain fluorescein in the tissues and allow the visualization of mucosal structures without any additional staining. PATIENTS AND METHODS CLE optical imaging of the mucosa was performed in 16 patients who were undergoing CLE colonoscopy. Standard conventional biopsies were also obtained from both normal colonic mucosa and colonic polyps. De-paraffinized mucosal sections were examined under a fluorescence microscope for the presence and distribution of fluorescein, and then underwent immunostaining for expression of vascular endothelial growth factor (VEGF). RESULTS Standard mucosal biopsy sections from patients undergoing CLE displayed a strong fluorescence and showed well-delineated mucosal structures. In colonic adenomas, there was a 4.6-fold increased vascular permeability compared with normal mucosa (P<0.001), indicated by fluorescein leakage to the extravascular space. Immunostaining demonstrated an aberrantly increased expression of VEGF in the epithelium of colonic adenomas but not in the epithelium of normal mucosa or hyperplastic polyps. CONCLUSIONS This study shows for the first time that standard colonic biopsies obtained during CLE retain fluorescein, show excellent delineation of mucosal structures without additional staining, allow the evaluation of mucosal microvasculature and vascular permeability, and are suitable for immunostaining.
Collapse
Affiliation(s)
- E Coron
- Institut des Maladies de l'Appareil Digestif - INSERM U913, CIC 04 et Service d'Hépato-Gastroentérologie, Hôtel Dieu, CHU de Nantes, France
| | | | | | | | | | | | | |
Collapse
|
49
|
Ahluwalia A, Tarnawski AS. Critical role of hypoxia sensor--HIF-1α in VEGF gene activation. Implications for angiogenesis and tissue injury healing. Curr Med Chem 2012; 19:90-7. [PMID: 22300081 DOI: 10.2174/092986712803413944] [Citation(s) in RCA: 466] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 11/07/2011] [Accepted: 11/10/2011] [Indexed: 02/06/2023]
Abstract
Vascular injury of esophageal and gastrointestinal mucosa caused by injurious and ulcerogenic factors leads to the cessation of blood flow, ischemia, and hypoxia and tissue necrosis in form of erosions or ulcers. The re-establishment of blood vessels through the process of angiogenesis--formation of new blood vessels--is critical for healing of tissue injury because is essential for delivery of oxygen and nutrients to the healing site. Hypoxia increases expression of hypoxia inducible factor (HIF-1), which serves as hypoxia sensor and activates compensatory and adaptive mechanisms. However, the molecular mechanisms and the role of HIF-1α in hypoxia-driven cellular and molecular events of angiogenesis in gastrointestinal injury healing have not been fully explored. The review discusses the novel molecular mechanisms of angiogenesis in gastric and esophageal mucosa with focus on HIF1α and VEGF interactions during healing of gastric mucosal injury and esophageal ulcers. HIF-1α is upregulated by gastric mucosal injury and esophageal ulcers; this upregulation correlates with VEGF gene activation and initiation of angiogenesis. The non-steroidal anti-inflammatory drugs (NSAIDs) interfere with hypoxia-induced HIF-1α accumulation, VEGF gene activation and angiogenesis through upregulation of von Hippel- Lindau (VHL) tumor suppressor, which activates degradation of HIF-1α protein. HIF-1α is a transcription factor that under hypoxic conditions, accumulates in endothelial cells and can bind to VEGF gene promoter and induce VEGF gene expression. In order to activate the VEGF gene, HIF-1α must be transported to the nucleus. Recent evidence implicates importins as key mechanism in this process.
Collapse
Affiliation(s)
- A Ahluwalia
- VA Long Beach Healthcare System & the University of California, Irvine, 5901 E. 7th Street, Long Beach, CA 90822-5201, USA.
| | | |
Collapse
|
50
|
Tarnawski AS, Ahluwalia A. Molecular mechanisms of epithelial regeneration and neovascularization during healing of gastric and esophageal ulcers. Curr Med Chem 2012; 19:16-27. [PMID: 22300072 DOI: 10.2174/092986712803414088] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 11/03/2011] [Accepted: 11/07/2011] [Indexed: 02/06/2023]
Abstract
In this paper we reviewed and updated current views on the cellular and molecular mechanisms of gastric and esophageal ulcer healing. Gastric ulcer healing encompasses inflammation, cell proliferation, epithelial regeneration, gland reconstruction, formation of granulation tissue, neovascularization (new blood vessel formation), interactions between various cells and the matrix and tissue remodeling, resulting in scar formation. All these events are controlled by the cytokines and growth factors, GI hormones including gastrin, CCK, and orexigenic peptides such as ghrelin, orexin-A and obestatin as well as Cox2 generated prostaglandins. These growth factors and hormones trigger cell proliferation, migration, and survival utilizing Ras, MAPK, PI-3K/AKT, PLC-γ and Rho/Rac/actin signaling pathways. Hypoxia triggers activation of some of these genes (e.g., VEGF) via hypoxia inducible factor (HIF). Growth factors: EGF, HGF, IGF-1, their receptors and Cox2 are important for epithelial cell proliferation, migration, re-epithelialization and regeneration of gastric glands during gastric ulcer healing. Serum response factor (SRF) is also essential for re-epithelialization and muscle restoration. VEGF, bFGF, angiopoietins, nitric oxide, endothelin, prostaglandins and metalloproteinases are important for angiogenesis, vascular remodeling and mucosal regeneration within gastric ulcer scar. SRF is critical limiting factor for VEGF-induced angiogenesis. Esophageal ulcer healing follows similar pattern to gastric ulcer, but KGF and its receptor are the key players in regeneration of the epithelium. In addition to local mucosal cells from viable mucosa bordering necrosis, circulating bone marrow derived stem and progenitor cells are potentially important for ulcer healing, contributing to the regeneration of epithelial and connective tissue components and neovascularization.
Collapse
Affiliation(s)
- A S Tarnawski
- Veterans Administration Long Beach Healthcare System, 5901 E. 7th Street, Long Beach, CA 90822-5201, USA.
| | | |
Collapse
|