1
|
Santillo M, Tonkin-Crine S, Wang K, Butler CC, Wanat M. Management of asthma in primary care in the changing context of the COVID-19 pandemic: a qualitative longitudinal study with patients. Br J Gen Pract 2023; 73:e903-e914. [PMID: 37429732 PMCID: PMC10355814 DOI: 10.3399/bjgp.2022.0581] [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: 11/23/2022] [Accepted: 04/04/2023] [Indexed: 07/12/2023] Open
Abstract
BACKGROUND The COVID-19 pandemic dramatically affected asthma monitoring in primary care, but exploration of patients' views and their experiences of managing their asthma and seeking help from primary care during the pandemic has been limited. AIM To investigate patients' experiences of asthma management in the community during the COVID-19 pandemic. DESIGN AND SETTING A qualitative longitudinal study using semi-structured interviews with patients from four GP practices across diverse regions including Thames Valley, Greater Manchester, Yorkshire, and North West Coast. METHOD Interviews were undertaken with patients with asthma, who were usually managed in primary care. The interviews were audiorecorded, transcribed, and analysed using inductive temporal thematic analysis and a trajectory approach. RESULTS Forty-six interviews were conducted with 18 patients over an 8-month period that covered contrasting stages of the COVID-19 pandemic. Patients felt less vulnerable as the pandemic subsided, but the process of making sense of risk was dynamic and influenced by multiple factors. Patients relied on self-management strategies, but felt that routine asthma reviews should still have been conducted during the pandemic and highlighted that they had limited opportunities to discuss their asthma with health professionals. Patients with well-controlled symptoms felt that remote reviews were largely satisfactory, but still thought face-to-face reviews were necessary for certain aspects, such as physical examination and patient-led discussions of sensitive or broader issues associated with asthma, including mental health. CONCLUSION The dynamic nature of patients' perception of risk throughout the pandemic highlighted the need for greater clarity regarding personal risk. Having an opportunity to discuss their asthma is important to patients, even when access to face-to-face consultations in primary care is more restricted than usual.
Collapse
Affiliation(s)
- Marta Santillo
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford
| | - Sarah Tonkin-Crine
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford
| | - Kay Wang
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford
| | - Christopher C Butler
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford
| | - Marta Wanat
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford
| |
Collapse
|
2
|
Armitage KF, Porter CE, Ahmed S, Cook J, Boards J, Bongard E, Butler CC, Corfield K, Davoudianfar M, Galal U, Howard P, Mujica-Mota R, Saman R, Santillo M, Savic S, Shinkins B, Tonkin-Crine S, Wanat M, West RM, Yu LM, Pavitt S, Sandoe JAT. Penicillin allergy status and its effect on antibiotic prescribing, patient outcomes and antimicrobial resistance (ALABAMA): protocol for a multicentre, parallel-arm, open-label, randomised pragmatic trial. BMJ Open 2023; 13:e072253. [PMID: 37666558 PMCID: PMC10481831 DOI: 10.1136/bmjopen-2023-072253] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 07/07/2023] [Indexed: 09/06/2023] Open
Abstract
INTRODUCTION Incorrect penicillin allergy records are recognised as an important barrier to the safe treatment of infection and affect an estimated 2.7 million people in England. Penicillin allergy records are associated with worse health outcome and antimicrobial resistance. The ALlergy AntiBiotics And Microbial resistAnce (ALABAMA) trial aims to determine if an intervention package, centred around a penicillin allergy assessment pathway (PAAP) initiated in primary care, is safe and effective in improving patient health outcomes and antibiotic prescribing. METHODS AND ANALYSIS The ALABAMA trial is a multicentre, parallel-arm, open-label, randomised pragmatic trial with a nested pilot study. Adults (≥18 years) with a penicillin allergy record and who have received antibiotics in the previous 24 months will be eligible for participation. Between 1592 and 2090 participants will be recruited from participating National Health Service general practices in England. Participants will be randomised to either usual care or intervention to undergo a pre-emptive PAAP using a 1:1 allocation ratio. The primary outcome measure is the percentage of treatment response failures within 28 days of an index prescription. 2090 and 1592 participants are estimated to provide 90% and 80% power, respectively, to detect a clinically important absolute difference of 7.9% in primary outcome at 1 year between groups. The trial includes a mixed-methods process evaluation and cost-effectiveness evaluation. ETHICS AND DISSEMINATION This trial has been approved by London Bridge Research Ethics Committee (ref: 19/LO/0176). It will be conducted in compliance with Good Clinical Practice guidelines according to the Declaration of Helsinki. Informed consent will be obtained from all subjects involved in the study. The primary trial results will be submitted for publication to an international, peer-reviewed journal. TRIAL REGISTRATION ISRCTN20579216.
Collapse
Affiliation(s)
- Kelsey Fiona Armitage
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Catherine E Porter
- Dental Translational and Clinical Research Unit, School of Dentistry, University of Leeds, Leeds, West Yorkshire, UK
| | - Shadia Ahmed
- Leeds Teaching Hospitals NHS Trust, Leeds, Leeds, UK
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, Leeds, UK
| | - Johanna Cook
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Jenny Boards
- Leeds Teaching Hospitals NHS Trust, Leeds, Leeds, UK
| | - Emily Bongard
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Christopher C Butler
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Kate Corfield
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Mina Davoudianfar
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Ushma Galal
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Philip Howard
- School of Healthcare, University of Leeds, Leeds, UK
- NHS England, Leeds, UK
| | - Ruben Mujica-Mota
- Academic Unit of Health Economics, Leeds Institute of Health Sciences, University of Leeds, Leeds, UK
| | - Razan Saman
- Leeds Teaching Hospitals NHS Trust, Leeds, Leeds, UK
| | - Marta Santillo
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Sinisa Savic
- Clinical Immunology and Allergy, University of Leeds Leeds Institute of Medical Research at St James's, Leeds, UK
| | - Bethany Shinkins
- Academic Unit of Health Economics, Leeds Institute of Health Sciences, University of Leeds, Leeds, UK
| | - Sarah Tonkin-Crine
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Marta Wanat
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Robert M West
- Leeds Institute of Health Sciences, University of Leeds, Leeds, UK
| | - Ly-Mee Yu
- Nuffield Department of Primary Care Health Sciences, Clinical Trials Unit, University of Oxford, Oxford, UK
| | - Sue Pavitt
- Dental Translational and Clinical Research Unit, School of Dentistry, University of Leeds, Leeds, West Yorkshire, UK
| | - Jonathan A T Sandoe
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, Leeds, UK
| |
Collapse
|
3
|
Wanat M, Santillo M, Galal U, Davoudianfar M, Bongard E, Savic S, Savic L, Porter C, Fielding J, Butler CC, Pavitt S, Sandoe J, Tonkin-Crine S. Mixed-methods evaluation of a behavioural intervention package to identify and amend incorrect penicillin allergy records in UK general practice. BMJ Open 2022; 12:e057471. [PMID: 36691248 PMCID: PMC9171226 DOI: 10.1136/bmjopen-2021-057471] [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] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 05/11/2022] [Indexed: 01/27/2023] Open
Abstract
OBJECTIVES About 6% of the UK general practice population has a record of a penicillin allergy but fewer than 10% of these are likely to be truly allergic. In the ALABAMA (Allergy Antibiotics and Microbial resistance) feasibility trial, primary care patients with penicillin allergy were randomised to penicillin allergy assessment pathway or usual care to assess the effect on health outcomes. A behavioural intervention package was developed to aid delabelling. This study aimed to investigate patients' and clinicians' views of penicillin allergy testing (PAT). DESIGN We conducted a mixed-methods process evaluation embedded within the ALABAMA trial, which included a clinician survey, a patient survey (at baseline and follow-up) and semistructured interviews with patients and clinicians. SETTINGS The study was conducted in primary care, as part of the feasibility stage of the ALABAMA trial. PARTICIPANTS Patients and primary care clinicians. RESULTS Clinicians (N=53; 52.2%) were positive about PAT and its potential value but did not have previous experience of referring patients for a PAT and were unsure whether patients would take penicillin after a negative allergy test. Patients (N=36; 46%) were unsure whether they were severely allergic to penicillin and did not fear a severe allergic reaction to penicillin. Clinician interviews showed that they were already aware of the benefit of PAT. Interviews with patients suggested the importance of safety as patients valued having numerous opportunities to address their concerns about safety of the test. CONCLUSIONS This study highlights the positive effects of the ALABAMA behavioural intervention for both patients and clinicians. TRIAL REGISTRATION NUMBER NCT04108637; ISRCTN20579216; Pre-results.
Collapse
Affiliation(s)
- Marta Wanat
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Marta Santillo
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Ushma Galal
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Mina Davoudianfar
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Emily Bongard
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Sinisa Savic
- University of Leeds and Leeds Teaching Hospitals NHS Trust, Faculty of Medicine and Health, Leeds, UK
| | - Louise Savic
- University of Leeds and Leeds Teaching Hospitals NHS Trust, Faculty of Medicine and Health, Leeds, UK
| | - Catherine Porter
- Healthcare Associated Infection Group, University of Leeds and Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Joanne Fielding
- Healthcare Associated Infection Group, University of Leeds and Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Christopher C Butler
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Sue Pavitt
- Dental Translational and Clinical Research Unit, Faculty of Medicine and Health, University of Leeds, Leeds, UK
| | - Jonathan Sandoe
- Healthcare Associated Infection Group, University of Leeds and Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Sarah Tonkin-Crine
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
- National Institute for Health Research (NIHR) Health Protection Research Unit (HPRU) in Healthcare Associated Infections and Antimicrobial Resistance, University of Oxford, Oxford, UK
| |
Collapse
|
4
|
Wanat M, Santillo M, Borek AJ, Butler CC, Anthierens S, Tonkin-Crine S. OUP accepted manuscript. JAC Antimicrob Resist 2022; 4:dlac026. [PMID: 35321397 PMCID: PMC8935206 DOI: 10.1093/jacamr/dlac026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
In order to design appropriate antimicrobial stewardship (AMS) programmes, it is crucial to understand challenges to tackling antibiotic resistance (AMR) specific to each healthcare setting. Antibiotic prescribing in primary care accounts for most prescriptions with a significant proportion considered clinically inappropriate. Qualitative research has a long history in social sciences, but its value and contribution are still contested in medical journals including in the AMR/AMS field. However, through its focus on understanding, meaning making and explaining, qualitative research can offer insights in how to improve AMS efforts in primary care. This paper provides an overview of unique considerations, contributions and challenges related to using qualitative research in AMS to help the AMS community new to qualitative research to utilize its potential most fully. First, we discuss specific considerations for AMS in relation to the stages of conducting a qualitative study, including identifying a research question and choosing a suitable methodology; sampling appropriate participants; planning a recruitment strategy; choosing a method of data collection; and conducting data analysis. These are illustrated with examples of qualitative AMS studies in primary care. Second, we highlight the importance of patient and public involvement throughout all stages of the project and ensuring quality in qualitative AMS research. Finally, drawing on these considerations, we make a further case for the value and contribution of qualitative methodologies in AMS/AMR research while outlining future directions for both AMS and qualitative research, including the need for studies with diverse actors; interdisciplinary collaborations; and complex decisions on methodologies and timelines.
Collapse
Affiliation(s)
- Marta Wanat
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
- Corresponding author. E-mail: ; @SKGTonkinCrine, @BorekAleksandra, @MartaSantillo, @marta_wanat, @sibylanthierens, @ChrisColButler
| | - Marta Santillo
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Aleksandra J. Borek
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Christopher C. Butler
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Sibyl Anthierens
- Department of Family Medicine and Population Health, University of Antwerp, Antwerp, Belgium
| | - Sarah Tonkin-Crine
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
- National Institute for Health Research Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, Oxford, UK
| |
Collapse
|
5
|
Abstract
Antibiotic use (and misuse) accelerates antimicrobial resistance (AMR), and addressing this complex problem necessitates behaviour change related to infection prevention and management and to antibiotic prescribing and use. As most antibiotic courses are prescribed in primary care, a key focus of antimicrobial stewardship (AMS) is on changing behaviours outside of hospital. Behavioural science draws on behaviour change theories, techniques and methods developed in health psychology, and can be used to help understand and change behaviours related to AMR/AMS. Qualitative methodologies can be used together with a behavioural science approach to explore influences on behaviour and develop and evaluate behavioural interventions. This paper provides an overview of how the behavioural science approach, together with qualitative methods, can contribute and add value to AMS projects. First, it introduces and explains the relevance of the behavioural science approach to AMR/AMS. Second, it provides an overview of behaviour change ‘tools’: behaviour change theories/models, behavioural determinants and behaviour change techniques. Third, it explains how behavioural methods can be used to: (i) define a clinical problem in behavioural terms and identify behavioural influences; (ii) develop and implement behavioural AMS interventions; and (iii) evaluate them. These are illustrated with examples of using qualitative methods in AMS studies in primary care. Finally, the paper concludes by summarizing the main contributions of taking the behavioural science approach to qualitative AMS research in primary care and discussing the key implications and future directions for research and practice.
Collapse
Affiliation(s)
- Aleksandra J. Borek
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
- Corresponding author. E-mail:
| | - Marta Santillo
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Marta Wanat
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Christopher C. Butler
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
- National Institute for Health Research (NIHR) Health Protection Research Unit (HPRU) in Healthcare Associated Infections and Antimicrobial Resistance, University of Oxford, Oxford, UK
| | - Sarah Tonkin-Crine
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
- National Institute for Health Research (NIHR) Health Protection Research Unit (HPRU) in Healthcare Associated Infections and Antimicrobial Resistance, University of Oxford, Oxford, UK
| |
Collapse
|
6
|
Albury C, Pope C, Shaw S, Greenhalgh T, Ziebland S, Martin S, Rai T, Chisholm A, Barnes R, White A, Wanat M, Santillo M, Boylan AM, Tremblett M, Tonkin-Crine S, Borek A, Sanders R, Koutoukidis D, Scragg J, Lee C, Russell S, Mikulak M, Logan M, Spratt T, Livingston-Banks J, Mcniven A, Stepney M, Talbot A, Crocker J, Powell J, Paparini S, Van der Westhuizen HM, Walumbe J, Newhouse N, Ryan S, Webb H, Mellor K, Potter C, Butler A, Pilbeam C. Gender in the consolidated criteria for reporting qualitative research (COREQ) checklist. Int J Qual Health Care 2021; 33:6357106. [PMID: 34428303 DOI: 10.1093/intqhc/mzab123] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/23/2021] [Indexed: 11/14/2022] Open
Affiliation(s)
- Charlotte Albury
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Catherine Pope
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Sara Shaw
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Trisha Greenhalgh
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Sue Ziebland
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Sam Martin
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Tanvi Rai
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Alison Chisholm
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Rebecca Barnes
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Ashley White
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Marta Wanat
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Marta Santillo
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Anne-Marie Boylan
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Madeline Tremblett
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Sarah Tonkin-Crine
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Aleksandra Borek
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Ruth Sanders
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Dimitrios Koutoukidis
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Jadine Scragg
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Charlotte Lee
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Siabhainn Russell
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK.,Department of Social Care & Social Work, Faculty of Health, Psychology & Social Care, Manchester Metropolitan University, Manchester M15 6GX, UK
| | - Magdalena Mikulak
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK.,Department of Social Care & Social Work, Faculty of Health, Psychology & Social Care, Manchester Metropolitan University, Manchester M15 6GX, UK
| | - Mary Logan
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Tanisha Spratt
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | | | - Abigall Mcniven
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Melissa Stepney
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Amelia Talbot
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Joanna Crocker
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - John Powell
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Sara Paparini
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | | | - Jackie Walumbe
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Nicola Newhouse
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Sara Ryan
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK.,Department of Social Care & Social Work, Faculty of Health, Psychology & Social Care, Manchester Metropolitan University, Manchester M15 6GX, UK
| | - Helena Webb
- Department of Computer Science, Human Centred Computing (HCC), University of Oxford, Oxford OX1 3LW, UK
| | - Katie Mellor
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford OX3 7HE, UK
| | - Caroline Potter
- Nuffield Department of Population Health, Health Services Research Unit, Oxford OX3 7LF, UK
| | - Ailsa Butler
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| | - Caitlin Pilbeam
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford OX2 6GG, UK
| |
Collapse
|
7
|
Mowbray F, Sivyer K, Santillo M, Jones N, Peto TEA, Walker AS, Llewelyn MJ, Yardley L. Patient engagement with antibiotic messaging in secondary care: a qualitative feasibility study of the ‘review and revise’ experience. Pilot Feasibility Stud 2020; 6:43. [PMID: 32280483 PMCID: PMC7126355 DOI: 10.1186/s40814-020-00590-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 03/24/2020] [Indexed: 01/22/2023] Open
Abstract
Abstract
Background
We aimed to investigate and optimise the acceptability and usefulness of a patient leaflet about antibiotic prescribing decisions made during hospitalisation, and to explore individual patient experiences and preferences regarding the process of antibiotic prescription ‘review and revise’ which is a key strategy to minimise antibiotic overuse in hospitals.
Methods
In this qualitative study, run within the feasibility study of a large, cluster-randomised stepped wedge trial of 36 hospital organisations, a series of semi-structured, think-aloud telephone interviews were conducted and data were analysed using thematic analysis. Fifteen adult patients who had experienced a recent acute medical hospital admission during which they had been prescribed antimicrobials and offered a patient leaflet about antibiotic prescribing were recruited to the study.
Results
Participants reacted positively to the leaflet, reporting that it was both an accessible and important source of information which struck the appropriate balance between informing and reassuring. Participants all valued open communication with clinicians, and were keen to be involved in antibiotic prescribing decisions, with individuals reporting positive experiences regarding antibiotic prescription changes or stopping. Many participants had prior experience or knowledge of antibiotics and resistance, and generally welcomed efforts to reduce antibiotic usage. Overall, there was a feeling that healthcare professionals (HCPs) are trusted experts providing the most appropriate treatment for individual patient conditions.
Conclusions
This study offers novel insights into how patients within secondary care are likely to respond to messages advocating a reduction in the use of antibiotics through the ‘review and revise’ approach. Due to the level of trust that patients place in their care provider, encouraging HCPs within secondary care to engage patients with greater communication and information provision could provide great advantages in the drive to reduce antibiotic use. It may also be beneficial for HCPs to view patient experiences as cumulative events that have the potential to impact future behaviour around antibiotic use. Finally, pre-testing messages about antibiotic prescribing and resistance is vital to dispelling any misconceptions either around effectiveness of treatment for patients, or perceptions of how messages may be received.
Trial registration
Current Controlled Trials ISRCTN12674243 (10 April 2017),
Collapse
|
8
|
Santillo M, Wanat M, Davoudianfar M, Bongard E, Savic S, Savic L, Porter C, Fielding J, Butler CC, Pavitt S, Sandoe J, Tonkin-Crine S. Developing a behavioural intervention package to identify and amend incorrect penicillin allergy records in UK general practice and subsequently change antibiotic use. BMJ Open 2020; 10:e035793. [PMID: 33004384 PMCID: PMC7534681 DOI: 10.1136/bmjopen-2019-035793] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 07/29/2020] [Accepted: 08/14/2020] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVES To develop a behavioural intervention package to support clinicians and patients to amend incorrect penicillin allergy records in general practice. The intervention aimed to: (1) support clinicians to refer patients for penicillin allergy testing (PAT), (2) support patients to attend for PAT and (3) support clinicians and patients to prescribe or consume penicillin, when indicated, following a negative PAT result. METHODS Theory-based, evidence-based and person-based approaches were used in the intervention development. We used evidence from a rapid review, two qualitative studies, and expert consultations with the clinical research team to identify the intervention 'guiding principles' and develop an intervention plan. Barriers and facilitators to the target behaviours were mapped to behaviour change theory in order to describe the proposed mechanisms of change. In the final stage, think-aloud interviews were conducted to optimise intervention materials. RESULTS The collated evidence showed that the key barriers to referral of patients by clinicians were limited experience of referral and limited knowledge of referral criteria and PAT. Barriers for patients attending PAT were lack of knowledge of the benefits of testing and lack of motivation to get tested. The key barriers to the prescription and consumption of first-line penicillin following a negative test result were patient and clinician beliefs about the accuracy of PAT and whether taking penicillin was safe. Intervention materials were designed and developed to address these barriers. CONCLUSIONS We present a novel behavioural intervention package designed to address the multiple barriers to uptake of PAT in general practice by clinicians and patients. The intervention development details how behaviour change techniques have been incorporated to hypothesise how the intervention is likely to work to help amend incorrect penicillin allergy records. The intervention will go on to be tested in a feasibility trial and randomised controlled trial in England.
Collapse
Affiliation(s)
- Marta Santillo
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Marta Wanat
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Mina Davoudianfar
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Emily Bongard
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | - Sinisa Savic
- Faculty of Medicine and Health, University of Leeds, Leeds, Leeds, UK
| | - Louise Savic
- Faculty of Medicine and Health, University of Leeds, Leeds, Leeds, UK
| | - Catherine Porter
- Healthcare Associated Infection Group, University of Leeds, Leeds, West Yorkshire, UK
| | - Joanne Fielding
- Healthcare Associated Infection Group, University of Leeds, Leeds, West Yorkshire, UK
| | - Christopher C Butler
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| | | | - Jonathan Sandoe
- Healthcare Associated Infection Group, University of Leeds, Leeds, West Yorkshire, UK
| | - Sarah Tonkin-Crine
- Nuffield Department of Primary Care Health Sciences, Oxford University, Oxford, UK
| |
Collapse
|
9
|
Santillo M, Sivyer K, Krusche A, Mowbray F, Jones N, Peto TEA, Walker AS, Llewelyn MJ, Yardley L. Intervention planning for Antibiotic Review Kit (ARK): a digital and behavioural intervention to safely review and reduce antibiotic prescriptions in acute and general medicine. J Antimicrob Chemother 2020; 74:3362-3370. [PMID: 31430366 PMCID: PMC6798845 DOI: 10.1093/jac/dkz333] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 05/07/2019] [Accepted: 07/07/2019] [Indexed: 12/11/2022] Open
Abstract
Background Hospital antimicrobial stewardship strategies, such as ‘Start Smart, Then Focus’ in the UK, balance the need for prompt, effective antibiotic treatment with the need to limit antibiotic overuse using ‘review and revise’. However, only a minority of review decisions are to stop antibiotics. Research suggests that this is due to both behavioural and organizational factors. Objectives To develop and optimize the Antibiotic Review Kit (ARK) intervention. ARK is a complex digital, organizational and behavioural intervention that supports implementation of ‘review and revise’ to help healthcare professionals safely stop unnecessary antibiotics. Methods A theory-, evidence- and person-based approach was used to develop and optimize ARK and its implementation. This was done through iterative stakeholder consultation and in-depth qualitative research with doctors, nurses and pharmacists in UK hospitals. Barriers to and facilitators of the intervention and its implementation, and ways to address them, were identified and then used to inform the intervention’s development. Results A key barrier to stopping antibiotics was reportedly a lack of information about the original prescriber’s rationale for and their degree of certainty about the need for antibiotics. An integral component of ARK was the development and optimization of a Decision Aid and its implementation to increase transparency around initial prescribing decisions. Conclusions The key output of this research is a digital and behavioural intervention targeting important barriers to stopping antibiotics at review (see http://bsac-vle.com/ark-the-antibiotic-review-kit/ and http://antibioticreviewkit.org.uk/). ARK will be evaluated in a feasibility study and, if successful, a stepped-wedge cluster-randomized controlled trial at acute hospitals across the NHS.
Collapse
Affiliation(s)
- M Santillo
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - K Sivyer
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - A Krusche
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - F Mowbray
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - N Jones
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - T E A Peto
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK.,Nuffield Department of Medicine, University of Oxford, Oxford, UK.,NIHR Biomedical Centre, Oxford, UK
| | - A S Walker
- Nuffield Department of Medicine, University of Oxford, Oxford, UK.,NIHR Biomedical Centre, Oxford, UK
| | - M J Llewelyn
- Brighton and Sussex Medical School, University of Sussex, Falmer, UK
| | - L Yardley
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK.,School of Psychological Science, University of Bristol, Bristol, UK
| | | |
Collapse
|
10
|
Cross ELA, Sivyer K, Islam J, Santillo M, Mowbray F, Peto TEA, Walker AS, Yardley L, Llewelyn MJ. Adaptation and implementation of the ARK (Antibiotic Review Kit) intervention to safely and substantially reduce antibiotic use in hospitals: a feasibility study. J Hosp Infect 2019; 103:268-275. [PMID: 31394146 DOI: 10.1016/j.jhin.2019.07.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 06/25/2019] [Accepted: 07/30/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND Antimicrobial stewardship initiatives in secondary care depend on clinicians undertaking antibiotic prescription reviews but decisions to limit antibiotic treatment at review are complex. AIM To assess the feasibility and acceptability of implementing ARK (Antibiotic Review Kit), a behaviour change intervention made up of four components (brief online tool, prescribing decision aid, regular data collection and feedback process, and patient leaflet) to support stopping antibiotic treatment when it is safe to do so among hospitalized patients; before definitive evaluation through a stepped-wedge cluster-randomized controlled trial. METHODS Acceptability of the different intervention elements was assessed for a period of 12 weeks by uptake of the online tool, adoption of the decision aid into prescribing practice, and rates of decisions to stop antibiotics at review (assessed through repeated point-prevalence surveys). Patient perceptions of the information leaflet were assessed through a brief questionnaire. FINDINGS All elements of the intervention were successfully introduced into practice. A total of 132 staff encompassing a broad range of prescribers and non-prescribers completed the online tool (19.4 per 100 acute beds), including 97% (32/33) of the pre-specified essential clinical staff. Among 588 prescription charts evaluated in seven point-prevalence surveys over the 12-week implementation period, 82% overall (76-90% at each survey) used the decision aid. The median antibiotic stop rate post implementation was 36% (range: 29-40% at each survey) compared with 9% pre implementation (P < 0.001). CONCLUSION ARK provides a feasible and acceptable mechanism to support stopping antibiotics safely at post-prescription reviews in an acute hospital setting.
Collapse
Affiliation(s)
- E L A Cross
- Brighton and Sussex Medical School, University of Sussex, Falmer, UK
| | - K Sivyer
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - J Islam
- Brighton and Sussex Medical School, University of Sussex, Falmer, UK
| | - M Santillo
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - F Mowbray
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - T E A Peto
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK; Nuffield Department of Medicine, University of Oxford, Oxford, UK; NIHR Biomedical Centre, Oxford, UK
| | - A S Walker
- Nuffield Department of Medicine, University of Oxford, Oxford, UK; NIHR Biomedical Centre, Oxford, UK
| | - L Yardley
- School of Psychological Science, University of Bristol, Bristol, UK
| | - M J Llewelyn
- Brighton and Sussex Medical School, University of Sussex, Falmer, UK.
| |
Collapse
|
11
|
Walker AS, Budgell E, Laskawiec-Szkonter M, Sivyer K, Wordsworth S, Quaddy J, Santillo M, Krusche A, Roope LSJ, Bright N, Mowbray F, Jones N, Hand K, Rahman N, Dobson M, Hedley E, Crook D, Sharland M, Roseveare C, Hobbs FDR, Butler C, Vaughan L, Hopkins S, Yardley L, Peto TEA, Llewelyn MJ. Antibiotic Review Kit for Hospitals (ARK-Hospital): study protocol for a stepped-wedge cluster-randomised controlled trial. Trials 2019; 20:421. [PMID: 31296255 PMCID: PMC6625068 DOI: 10.1186/s13063-019-3497-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 06/05/2019] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND To ensure patients continue to get early access to antibiotics at admission, while also safely reducing antibiotic use in hospitals, one needs to target the continued need for antibiotics as more diagnostic information becomes available. UK Department of Health guidance promotes an initiative called 'Start Smart then Focus': early effective antibiotics followed by active 'review and revision' 24-72 h later. However in 2017, < 10% of antibiotic prescriptions were discontinued at review, despite studies suggesting that 20-30% of prescriptions could be stopped safely. METHODS/DESIGN Antibiotic Review Kit for Hospitals (ARK-Hospital) is a complex 'review and revise' behavioural intervention targeting healthcare professionals involved in antibiotic prescribing or administration in inpatients admitted to acute/general medicine (the largest consumers of non-prophylactic antibiotics in hospitals). The primary study objective is to evaluate whether ARK-Hospital can safely reduce the total antibiotic burden in acute/general medical inpatients by at least 15%. The primary hypotheses are therefore that the introduction of the behavioural intervention will be non-inferior in terms of 30-day mortality post-admission (relative margin 5%) for an acute/general medical inpatient, and superior in terms of defined daily doses of antibiotics per acute/general medical admission (co-primary outcomes). The unit of observation is a hospital organisation, a single hospital or group of hospitals organised with one executive board and governance framework (National Health Service trusts in England; health boards in Northern Ireland, Wales and Scotland). The study comprises a feasibility study in one organisation (phase I), an internal pilot trial in three organisations (phase II) and a cluster (organisation)-randomised stepped-wedge trial (phase III) targeting a minimum of 36 organisations in total. Randomisation will occur over 18 months from November 2017 with a further 12 months follow-up to assess sustainability. The behavioural intervention will be delivered to healthcare professionals involved in antibiotic prescribing or administration in adult inpatients admitted to acute/general medicine. Outcomes will be assessed in adult inpatients admitted to acute/general medicine, collected through routine electronic health records in all patients. DISCUSSION ARK-Hospital aims to provide a feasible, sustainable and generalisable mechanism for increasing antibiotic stopping in patients who no longer need to receive them at 'review and revise'. TRIAL REGISTRATION ISRCTN Current Controlled Trials, ISRCTN12674243 . Registered on 10 April 2017.
Collapse
Affiliation(s)
- Ann Sarah Walker
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Eric Budgell
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Magda Laskawiec-Szkonter
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford Respiratory Trials Unit, University of Oxford, Oxford, UK
| | - Katy Sivyer
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - Sarah Wordsworth
- Health Economics Research Centre, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - Jack Quaddy
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford Respiratory Trials Unit, University of Oxford, Oxford, UK
| | - Marta Santillo
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - Adele Krusche
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - Laurence S. J. Roope
- Health Economics Research Centre, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - Nicole Bright
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Fiona Mowbray
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
| | - Nicola Jones
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Kieran Hand
- University of Southampton, Southampton, UK
- University Hospital Southampton NHS Trust, Southampton, UK
| | - Najib Rahman
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford Respiratory Trials Unit, University of Oxford, Oxford, UK
| | - Melissa Dobson
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford Respiratory Trials Unit, University of Oxford, Oxford, UK
| | - Emma Hedley
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford Respiratory Trials Unit, University of Oxford, Oxford, UK
| | - Derrick Crook
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | | | | | - F. D. Richard Hobbs
- Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Chris Butler
- Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | | | - Susan Hopkins
- Royal Free London NHS Foundation Trust, London, UK
- National Infection Service, Public Health England, London, UK
| | - Lucy Yardley
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
- School of Psychological Science, University of Bristol, Clifton, UK
| | - Timothy E. A. Peto
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | | | - on behalf of the ARK trial team
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Oxford Respiratory Trials Unit, University of Oxford, Oxford, UK
- Centre for Clinical and Community Applications of Health Psychology, University of Southampton, Southampton, UK
- Health Economics Research Centre, Nuffield Department of Population Health, University of Oxford, Oxford, UK
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
- University of Southampton, Southampton, UK
- University Hospital Southampton NHS Trust, Southampton, UK
- St George’s, University of London, London, UK
- Southern Health NHS Foundation Trust, Southampton, UK
- Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
- The Nuffield Trust, London, UK
- Royal Free London NHS Foundation Trust, London, UK
- School of Psychological Science, University of Bristol, Clifton, UK
- National Infection Service, Public Health England, London, UK
- Brighton and Sussex Medical School, Brighton, UK
| |
Collapse
|
12
|
Abstract
The cytotoxicity of dental monomers has been widely investigated, but the underlying mechanisms have not been elucidated. We studied the molecular mechanisms involved in cell death induced by HEMA. In human primary fibroblasts, HEMA induced a dose-dependent apoptosis that was confirmed by the activation of caspases-8, -9, and -3. We found an increase of reactive oxygen species (ROS) and NF-κB activation after HEMA exposure. Blocking of ROS production by anti-oxidants had no direct influence on apoptosis caused by HEMA, but inhibition of NF-κB increased the fraction of apoptotic cells. Accordingly, mouse embryonic fibroblasts (MEF) from p65−/− mice were more susceptible to HEMA-induced apoptosis than were wild-type controls. Our results indicate that exposure to HEMA triggers apoptosis and that this mechanism is not directly dependent upon redox signaling. Nevertheless, ROS induction by HEMA activates NF-κB, which exerts a protective role in counteracting apoptosis.
Collapse
Affiliation(s)
- G Spagnuolo
- Department of Oral and Maxillofacial Sciences, University of Naples, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Abstract
BACKGROUND Mentorship has been identified as a beneficial practice for doctors and may be particularly valuable for newly appointed consultants. It is associated with a number of potential clinical and non-clinical gains, such as enhanced job satisfaction and well-being. Despite strong support, many formalised schemes fail to launch or gain momentum. Research to date has largely focused on the gains associated with mentorship but has lacked study of the factors that facilitate uptake and maintenance of mentoring relationships by physicians. OBJECTIVES To explore perceptions of mentorship, the extent to which UK doctors appear to value mentorship and factors that may contribute to its successful use. DESIGN Qualitative, descriptive, multi-centre study. SAMPLE 30 doctors including registrars, those newly appointed to consultant grade, senior doctors and medical leaders from nine hospitals in the north of England. METHOD Semistructured individual interviews were undertaken between August and December 2013. RESULTS Findings revealed a demand for mentorship for new consultants, with widely recognised benefits associated with its use. Several factors were identified as critical to successful mentorship relationships, including consistent understanding and expectations of mentorship between mentee and mentor, positive prior experiences, a suitable match between mentee and mentor, making time for people to act as mentors and the ensuring that mentors can meet a diverse and changing set of needs. CONCLUSIONS Mentorship for newly appointed consultants is valued, but current models of mentorship may suffer from rigid structures, mismatched expectations of participants and the absence of a culture of mentorship from training into practice. A social network approach, in which doctors have the opportunity to engage with a range of mentors through informal and naturally occurring relationships, may be one way to encourage successful and sustained mentoring relationships among doctors. An organisational culture in which mentorship is permitted and is the norm may enable such approaches to be widely adopted.
Collapse
Affiliation(s)
- Reema Harrison
- School of Public Health, Sydney Medical School, University of Sydney, Sydney, Australia
| | - John Anderson
- Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford, UK
| | - Pierre-Antoine Laloë
- Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford, UK
| | - Marta Santillo
- Institute for Psychological Sciences, University of Leeds, Leeds, West Yorkshire, UK
| | - Rebecca Lawton
- Institute for Psychological Sciences, University of Leeds, Leeds, West Yorkshire, UK
| | - John Wright
- Bradford Institute for Health Research, Bradford Teaching Hospitals NHS Foundation Trust, Bradford, UK
| |
Collapse
|
14
|
Viggiano A, Serù R, Damiano S, De Luca B, Santillo M, Mondola P. Inhibition of long-term potentiation by CuZn superoxide dismutase injection in rat dentate gyrus: involvement of muscarinic M1 receptor. J Cell Physiol 2012; 227:3111-5. [PMID: 22015651 DOI: 10.1002/jcp.23062] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Long-term potentiation (LTP) and long-term depression represent important processes that modulate synaptic transmission that carries out a key role in neural mechanisms of memory. Many studies give strong evidences on a role of the reactive oxygen species in the induction of LTP in CA1 region of hippocampal slices that was inhibited by adding the scavenger enzyme superoxide dismutase (SOD1). Previous data showed that SOD1 is secreted by many cellular lines, including neuroblastoma SK-N-BE cells through microvesicles by an ATP-dependent mechanism; moreover, it has been shown that SOD1 interacts with human neuroblastoma cell membranes increasing intracellular calcium levels via a phospholipase C-protein kinase C pathway activation. The aim of this study was to investigate the effect of intracerebral injection of SOD1 or the inactive form of enzyme (ApoSOD) on the modulation of synaptic transmission in dentate gyrus of the hippocampus in urethane anesthetized rats. The results of the present research showed that intracerebral injection of SOD1 and ApoSOD in the dentate gyrus of the rat hippocampal formation inhibits LTP induced by high-frequency stimulation of the perforant path. This result cannot be only explained by the dismutation of oxygen radical induced by SOD1 since also ApoSOD, that lacks the enzymatic activity, carries out the same inhibitory effect on LTP induction.
Collapse
Affiliation(s)
- A Viggiano
- Department of Experimental Medicine, Section of Human Physiology, Second University of Naples, Naples, Italy
| | | | | | | | | | | |
Collapse
|
15
|
Scorziello A, Santillo M, Adornetto A, Dell'aversano C, Sirabella R, Damiano S, Canzoniero LMT, Renzo GFD, Annunziato L. NO-induced neuroprotection in ischemic preconditioning stimulates mitochondrial Mn-SOD activity and expression via RAS/ERK1/2 pathway. J Neurochem 2007; 103:1472-80. [PMID: 17680990 DOI: 10.1111/j.1471-4159.2007.04845.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To identify the transductional mechanisms responsible for the neuroprotective effect of nitric oxide (NO) during ischemic preconditioning (IPC), we investigated the effects of this gaseous mediator on mitochondrial Mn-superoxide dismutase (Mn-SOD) expression and activity. In addition, the possible involvement of Ras/extracellular-regulated kinase (ERK) ERK1/2 pathway in preserving cortical neurons exposed to oxygen and glucose deprivation (OGD) followed by reoxygenation was also examined. Ischemic preconditioning was obtained by exposing neurons to a 30-min sublethal OGD (95% N(2) and 5% CO(2)). Then, after a 24-h interval, neurons were exposed to 3 h of OGD followed by 24 h of reoxygenation (OGD/Rx). Our results revealed that IPC reduced cytochrome c (cyt c) release into the cytosol, improved mitochondrial function, and decreased free radical production. Moreover, it induced an increase in nNOS expression and NO production and promoted ERK1/2 activation. These effects were paralleled by an increase in Mn-SOD expression and activity that persisted throughout the following OGD phase. When the neurons were treated with L-NAME, a well known NOS inhibitor, the increase in Mn-SOD expression occurring during IPC was reduced and, as a result, IPC-induced neuroprotection was prevented. Similarly, when ERK1/2 was inhibited by its selective inhibitor PD98059, the increase in Mn-SOD expression observed during IPC was almost completely abolished. As a result, its neuroprotective effect on cellular survival was thwarted. The present findings indicate that during IPC the increase in Mn-SOD expression and activity are paralleled by NO production. This suggests that NO neuroprotective role occurs through the stimulation of Mn-SOD expression and activity. In particular, NO via Ras activation stimulates downstream ERK1/2 cascade. This pathway, in turn, post-transcriptionally activates Mn-SOD expression and activity, thus promoting neuroprotection during preconditioning.
Collapse
Affiliation(s)
- A Scorziello
- Division of Pharmacology, Department of Neuroscience, University of Naples Federico II, Naples, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Abstract
The addition of epinephrine to solutions containing fentanyl and bupivacaine for epidural infusion has been shown to improve the quality of analgesia. However, this admixture is not available commercially in the United Kingdom. Moreover, stability data applicable to UK practice for this admixture are limited. This study investigated the stability of fentanyl 2 microg.ml(-1) plus bupivacaine 1 mg.ml(-1) in PVC bags with and without epinephrine 2 microg.ml(-1) over a period of 184 days both at room temperature and at 4 degrees C. All infusions were found to be stable over the study period (> 90% remaining) using stability-indicating High Performance Liquid Chromatography (HPLC) methods, with no changes in physical appearance or pH (range 4.5-4.2). The infusions were prepared using standard pharmaceutical products, so facilitating the batch preparation of epinephrine, fentanyl and bupivacaine epidural solutions by hospital pharmacy departments.
Collapse
Affiliation(s)
- M J Priston
- Pharmacy Department, Derriford Hospital, Plymouth, UK.
| | | | | | | |
Collapse
|
17
|
Abstract
The small GTPases Rab4, Rab5 and Rab7 are endosomal proteins which play important roles in the regulation of various stages of endosomal trafficking. Rab4 and Rab5 have both been localized to early endosomes and have been shown to control recycling and endosomal fusion, respectively. Rab7, a marker of the late endosomal compartment, is involved in the regulation of the late endocytic pathway. Here, we compare the role of Rab4, Rab5 and Rab7 in early and late endosomal trafficking in HeLa cells monitoring ligand uptake, recycling and degradation. Expression of the Rab4 dominant negative mutant (Rab4AS22N) leads to a significant reduction in both recycling and degradation while, as expected, Rab7 mutants exclusively affect epidermal growth factor (EGF) and low density lipoprotein degradation. As also expected, expression of the dominant negative Rab5 mutant perturbs internalization kinetics and affects both recycling and degradation. Expression of Rab4WT and dominant positive mutant (Rab4AQ67L) changes dramatically the morphology of the transferrin compartment leading to the formation of membrane tubules. These transferrin positive tubules display swellings (varicosities) some of which are positive for early endosomal antigen-1 and contain EGF. We propose that the Rab4GTPase is important for the function of the early sorting endosomal compartment, affecting trafficking along both recycling and degradative pathways.
Collapse
Affiliation(s)
- M W McCaffrey
- Cell and Molecular Biology Laboratory, Biochemistry Department, UCC, Cork, Ireland.
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Santillo M, Mondola P, Serù R, Annella T, Cassano S, Ciullo I, Tecce MF, Iacomino G, Damiano S, Cuda G, Paternò R, Martignetti V, Mele E, Feliciello A, Avvedimento EV. Opposing functions of Ki- and Ha-Ras genes in the regulation of redox signals. Curr Biol 2001; 11:614-9. [PMID: 11369207 DOI: 10.1016/s0960-9822(01)00159-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Ras p21 signaling is involved in multiple aspects of growth, differentiation, and stress response [1-2]. There is evidence pointing to superoxides as relays of Ras signaling messages. Chemicals with antioxidant activity suppress Ras-induced DNA synthesis. The inhibition of Ras significantly reduces the production of superoxides by the NADPH-oxidase complex [3]. Kirsten and Harvey are nonallelic Ras cellular genes that share a high degree of structural and functional homology. The sequences of Ki- and Ha-Ras proteins are almost identical. They diverge only in the 20-amino acid hypervariable domain at the COOH termini. To date, their functions remain indistinguishable [4]. We show that Ki- and Ha-Ras genes differently regulate the redox state of the cell. Ha-Ras-expressing cells produce high levels of reactive oxygen species (ROS) by inducing the NADPH-oxidase system. Ki-Ras, on the other hand, stimulates the scavenging of ROS by activating posttranscriptionally the mitochondrial antioxidant enzyme, Mn-superoxide dismutase (Mn-SOD), via an ERK1/2-dependent pathway. Glutamic acid substitution of the four lysine residues in the polybasic stretch at the COOH terminus of Ki-Ras completely abolishes the activation of Mn-SOD, although it does not inhibit ERK1/2-induced transcription. In contrast, an alanine substitution of the cysteine of the CAAX box has very little effect on Mn-SOD activity but eliminates ERK1/2- dependent transcription.
Collapse
Affiliation(s)
- M Santillo
- Dipartimento di Neuroscienze e di Scienze del Comportamento-Sezione di Fisiologia, Napoli, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Abstract
It has previously been demonstrated that CuZn-superoxide dismutase (SOD) is secreted by several human cell lines. This suggests that the circulating enzyme derives from both hemolysis and peripheral tissues as a result of cellular secretion. In the present report, we evaluated the presence of CuZn-SOD in human serum lipoproteins by both enzyme-linked immunosorbent assay and Western blot analysis of immunoprecipitated lipoprotein samples. The distribution of CuZn-SOD activity among the different lipoprotein fractions was also determined by the xanthine/xanthine oxidase method. The results demonstrated that CuZn-SOD is noticeably present in serum lipoproteins and mainly in low and high density lipoproteins (LDL and HDL). Moreover, experiments performed by incubating CuZn-SOD with a lipid emulsion and subsequent separation of the lipid fraction by ultracentrifugation showed that this enzyme associates in a saturable manner with lipids. The CuZn-SOD bound to LDL and HDL could exert a physiological protective role against oxidative damage of these lipoprotein classes that carry out a crucial role in the cholesterol transport.
Collapse
Affiliation(s)
- P Mondola
- Dipartimento di Neuroscienze e della Comunicazione Interumana-Sez. Fisiologia, Via S. Pansini 5, 80131, Naples, Italy.
| | | | | | | | | | | |
Collapse
|
20
|
Santillo M, Migliaro A, Mondola P, Laezza C, Damiano S, Stingo S, Fiorentino L, Andreozzi A, Vitale M, Bifulco M. Dietary and hypothyroid hypercholesterolemia induces hepatic apolipoprotein E expression in the rat: direct role of cholesterol. FEBS Lett 1999; 463:83-6. [PMID: 10601643 DOI: 10.1016/s0014-5793(99)01604-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Apolipoprotein E (apo E) exerts a protective effect against atherosclerosis, related to its role in intracellular cholesterol removal and remnants clearance. In this study we investigated the effect of dietary and hypothyroid hypercholesterolemia, induced respectively by a high cholesterol diet and by propylthiouracil, on hepatic apo E expression in Wistar male rats. The Northern and Western blot analysis of hepatic mRNA and protein levels showed a 2-3-fold increase of apo E in hypercholesterolemic rats compared to controls. The incubation of FAO rat hepatoma cells with 25-OH cholesterol and mevalonate led to a three-fold increase of apo E mRNA, demonstrating a direct role of cholesterol on apo E expression. This effect was completely abolished by elevating intracellular cAMP levels with forskolin. Immunoblot and immunofluorescence analysis revealed that 25-OH cholesterol/mevalonate strongly increased also apo E protein synthesis and secretion in FAO cells. Our data demonstrate that hypercholesterolemia, apart of the cause (diet or hypothyroidism) induces liver apo E expression in the rat and that this effect can be directly related, via cAMP, to cholesterol.
Collapse
Affiliation(s)
- M Santillo
- Dipartimento di Neuroscienze e della Comunicazione Interumana-Sezione di Fisiologia, Università di Napoli 'Federico II', Napoli, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Caruso MG, Notarnicola M, Santillo M, Cavallini A, Di Leo A. Enhanced 3-hydroxy-3-methyl-glutaryl coenzyme A reductase activity in human colorectal cancer not expressing low density lipoprotein receptor. Anticancer Res 1999; 19:451-4. [PMID: 10226581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
BACKGROUND We have previously shown that 63.3% of colorectal cancer neoplastic specimens did not express the Low Density Lipoprotein Receptor (LDLR) protein and that the absence of LDLR predicted shorter survival. We now report the findings of a preliminary study on HMG-CoA reductase (HMG-CoAR) activity in neoplastic tissue specimens of human colorectal cancers (CRC) expressing or not expressing LDLR. MATERIALS AND METHODS The tissue specimens were obtained from 16 patients (10 males and 6 females) undergoing surgical resection for CRC, and previously characterized for LDLR (7 not expressing LDLR and 9 expressing LDLR). HMG-CoAR activity was measured by radiochemical assay using 14C-HMG-CoA as substrate. RESULTS HMG-CoAR activity was significantly higher in specimens not expressing LDLR than in those expressing LDLR [8.3 pmol/min/mg prot (2.4-16) vs 3.9 pmol/min/mg prot (1.2-7.8), data expressed as median value and the range, p = 0.02, Wilcoxon Rank sum test)]. CONCLUSIONS The cholesterol requirement in CRC not expressing LDLR may be met by increasing endogenous synthesis. For this reason, the use of HMG-CoA R inhibitors for the treatment of CRC expressing high HMG-CoAR activity-dependence for growth may be clinically important.
Collapse
Affiliation(s)
- M G Caruso
- Laboratorio di Biochimica, IRCCS S. de Bellis, Castellana Grotte, BA, Italy
| | | | | | | | | |
Collapse
|
22
|
Abstract
Rab proteins are small molecular mass GTP-ases involved in the regulation of vescicular transport. The ability of rab proteins to carry out their role in intracellular membrane traffic requires the post-translational attachment to their C-terminus of a geranylgeranyl group, an isoprenoid lipid moiety derived from mevalonate. Here we report that depletion of intracellular mevalonate by lovastatin in FRTL-5 thyroid cells specifically resulted in a four-fold increase of Rab5 and Rab7 protein levels. This increase was reversed within 4 h upon addition of mevalonate. Similarly lovastatin also induced, at same extent, mRNA levels. Lovastatin effect was not common to other prenylated proteins. Moreover incubation with cycloheximide abolished the observed increase in lovastatin treated cells, suggesting that the effect is mediated by newly synthesized protein. These findings demonstrate that Rab5 and Rab7 expression are regulated by the isoprenoid pathway.
Collapse
Affiliation(s)
- C Laezza
- Centro di Endocrinologia ed Oncologia Sperimentale G. Salvatore del CNR, Italy
| | | | | | | | | |
Collapse
|
23
|
Abstract
It has been shown that dietary fatty acids affect serum low density lipoprotein (LDL) levels, but the mechanism responsible for this effect is still under debate. Here we investigate the effect of different free fatty acids on LDL receptor activity in BHK-21 cells. These cells possess a classical LDL receptor strongly regulated by substances like 25-OH-cholesterol or lovastatin. Preincubation of cells for 24 h with both oleic (cis 18:1) and its trans counterpart, elaidic acid, enhanced 125I-LDL binding, internalization and degradation, being oleic acid more effective than elaidic acid. Among polyunsaturated fatty acids (PUFA) of the n-6 series arachidonic acid (20:4) enhanced LDL receptor activity more than linoleic acid (18:2), and among PUFA of the n-3 series docosahexaenoic (22:6) and eicosapentaenoic acids (20:5) were more effective compared to alpha-linolenic acid (18:3). Conversely, preincubation of cells with saturated fatty acids, palmitic (16:0) and stearic (18:0) acids, decreased binding, internalization and degradation of 125I-LDL. Scatchard analysis of binding data obtained with palmitic and oleic acids showed that these two fatty acids affect LDL receptor number without altering receptor affinity. The regulatory effect of free fatty acids on LDL receptor activity in BHK-21 cells is consistent with the hypothesis that the ability of fatty acids to modulate LDL-cholesterol levels in vivo is mediated, at least in part, by an action on receptor-dependent uptake of LDL.
Collapse
Affiliation(s)
- C Bucci
- Dipartimento di Biologia e Patologia Cellulare e Molecolare L. Califano and Centro di Endocrinologia ed Oncologia Sperimentale del Consiglio Nazionale delle Ricerche, Napoli, Italy
| | | | | | | | | | | | | | | |
Collapse
|
24
|
Mondola P, Annella T, Serù R, Santangelo F, Iossa S, Gioielli A, Santillo M. Secretion and increase of intracellular CuZn superoxide dismutase content in human neuroblastoma SK-N-BE cells subjected to oxidative stress. Brain Res Bull 1998; 45:517-20. [PMID: 9570722 DOI: 10.1016/s0361-9230(97)00438-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
CuZn superoxide dismutase (SOD) secretion was detected in media of [35S]cysteine-labeled human neuroblastoma SK-N-BE cells precipitated with antihuman CuZn SOD antibodies. The ability of Fe2+/ascorbate oxidative stress to induce CuZn SOD in SK-N-BE cells was evaluated by Western blot analysis. The results showed that, like human hepatocarcinoma cells and human fibroblasts, SK-N-BE cells secrete CuZn SOD. In addition, the CuZn SOD concentration was higher in cells subjected to oxidative stress than in unstressed cells. The secretion of CuZn SOD and the ability of Fe2+/ascorbate to increase its protein content in SK-N-BE cells indicates that this enzyme protects the brain from damage induced by oxidative stress.
Collapse
Affiliation(s)
- P Mondola
- Dipartimento di Neuroscienze e della Communicazione Interumana, Sezione Fisiologia, Università degli Studi di Napoli Federico II, Naples, Italy.
| | | | | | | | | | | | | |
Collapse
|
25
|
Laezza C, Migliaro A, Cerbone R, Tedesco I, Santillo M, Garbi C, Bifulco M. N6-isopentenyladenosine affects cAMP-dependent microfilament organization in FRTL-5 thyroid cells. Exp Cell Res 1997; 234:178-82. [PMID: 9223384 DOI: 10.1006/excr.1997.3610] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
N6-Isopentenyladenosine (i6A), an adenosine and mevalonate derivative, inhibits, like adenosine, TSH-induced cAMP increase and its related events (I- uptake and DNA synthesis) in FRTL-5 cells. This inhibition is dose-dependent and is measurable at 10(-8) M. However, unlike adenosine, i6A prevents TSH-promoted microfilament disassembly. The effect of i6A on cytoskeletal structure is antagonized by pertussis toxin and could be assigned to its N6 substitution since it can be mimicked by other synthetic N6-adenosine derivatives. It is suggested that a step beyond cAMP is involved, since i6A prevents also microfilament disassembly induced by 8-bromo-cAMP. This is the first demonstration that an adenosine derivative, which is also an end-product of the isoprenoid pathway, affects cAMP-dependent microfilament organization.
Collapse
Affiliation(s)
- C Laezza
- Centro di Endocrinologia ed Oncologia Sperimentale del CNR, Dipartimento di Biologia e Patologia Cellulare e Molecolare, Università di Napoli Federico II, Naples, Italy
| | | | | | | | | | | | | |
Collapse
|
26
|
Abstract
Rab7 is a small GTPase localized to the late endosomal compartment. Its function was investigated by overexpressing dominant negative or constitutively active mutants in BHK-21 cells. The effects of such overexpression on the internalization and/or degradation of different endocytic markers and on the morphology of the late endosomal compartment were analyzed. We observed a marked inhibition of the degradation of 125I-low density lipoproteins in cells transfected with the Rab7 dominant negative mutants while the rate of internalization was not affected. Moreover in these cells there was an accumulation of many small vesicles scattered throughout the cytoplasm. In contrast, overexpression of the activating mutants led to the appearance of atypically large endocytic structures and caused a dramatic change in the distribution of the cation-independent mannose 6-phosphate receptor. Our data indicate that the Rab7 protein in mammalian cells is present on a late endosomal compartment much larger than the compartment labeled by the cation-independent mannose 6-phosphate receptor. Rab7 also appears to play a fundamental role in controlling late endocytic membrane traffic.
Collapse
Affiliation(s)
- R Vitelli
- Dipartimento di Biologia e Patologia Cellulare e Molecolare "L. Califano" and Centro di Endocrinologia ed Oncologia Sperimentale del Consiglio Nazionale delle Ricerche, Università di Napoli "Federico II," Via S. Pansini 5, 80131, Napoli, Italy
| | | | | | | | | | | | | |
Collapse
|
27
|
Santillo M, Mondola P, Gioielli A, Serù R, Iossa S, Annella T, Vitale M, Bifulco M. Inhibitors of Ras farnesylation revert the increased resistance to oxidative stress in K-Ras transformed NIH 3T3 cells. Biochem Biophys Res Commun 1996; 229:739-45. [PMID: 8954966 DOI: 10.1006/bbrc.1996.1874] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Tumor resistance to oxidative stress prevents the efficacy of cancer therapy based upon a free radical-mediated mechanism. K-ras transformed NIH 3T3 cells (E32-4-2) showed, under oxidative stress, reactive oxygen species (ROS) levels 10-fold lower and lipid peroxide levels 56% lower, compared to their nontransformed counterpart. Since p21(ras) activity depends upon farnesylation, we tested the effect of the inhibitors of farnesylation lovastatin and (alpha-hydroxyfarnesyl) phosphonic acid on susceptibility to oxidative stress in these cells. Preincubation of cells for 24 h with 10 microM lovastatin resulted in a 10-fold increase of ROS levels and a 50% increase of lipid peroxide levels measured under pro-oxidant conditions. Similarly, preincubation of cells with 100 microM (alpha-hydroxyfarnesyl) phosphonic acid for 24 h enhanced stress-induced levels of either ROS (7.5-fold) or lipid peroxides (33%). The effect of lovastatin and (alpha-hydroxyfarnesyl) phosphonic acid is specifically due to their ability to inhibit p21(ras) activity. In fact, inhibition of p21(ras) by transfecting E32-4-2 cells with the transdominant negative mutant of H-ras (L61, S186) led, analogously to lovastatin or (alpha-hydroxyfarnesyl) phosphonic acid treatment, to a strong increase of stress-induced ROS levels. These results suggest that farnesylation inhibitors could be used as an adjuvant therapy to improve the tumoricidal effect of cancer treatment based upon free-radical production in ras-dependent tumors.
Collapse
Affiliation(s)
- M Santillo
- Dipartimento di Neuroscienze, Sezione Fisiologia, Università degli Studi di Napoli "Federico II", Napoli, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
28
|
Mondola P, Annella T, Santillo M, Santangelo F. Evidence for secretion of cytosolic CuZn superoxide dismutase by Hep G2 cells and human fibroblasts. Int J Biochem Cell Biol 1996; 28:677-81. [PMID: 8673732 DOI: 10.1016/1357-2725(96)00004-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The role so far ascribed to intracellular CuZn superoxide dismutase is that of an intracellular scavenger of oxygen radicals. However, other functions of cytosolic CuZn superoxide dismutase have been hypothesized. For example, CuZn superoxide dismutase incubated with rat hepatocyte cells in culture inhibits 3-hydroxy-3methylglutaryl CoA reductase, thereby reducing cholesterol synthesis. We recently demonstrated the presence of surface membrane receptors for CuZn superoxide dismutase, suggesting possible autocrine or paracrine activities. The aim of the present study was to investigate whether cytosolic CuZn superoxide dismutase can be secreted by human hepatocarcinoma and fibroblast cells lines. Proteins in human hepatocellular carcinoma (Hep G2) cells and human fibroblasts were biosynthetically labelled with [35S]-cysteine; then cell lysates and media were immunoprecipitated with rabbit polyclonal anti-human CuZn superoxide dismutase antibodies and separated by 12% polyacrylamide gel electrophoresis. Both Hep G2 cells and human fibroblasts produce and secrete CuZn superoxide dismutase which was detectable in cells and medium as a single protein band with the same electrophoretic mobility as human erythrocyte CuZn superoxide dismutase. These data suggest that CuZn superoxide dismutase, an enzyme thus far considered to be located exclusively intracellularly is secreted by at least two cell lines. This is consistent with autocrine or paracrine roles for CuZn superoxide dismutase.
Collapse
Affiliation(s)
- P Mondola
- Department of Neuroscience, School of Medicine Federico II, University of Naples, Italy
| | | | | | | |
Collapse
|
29
|
Santillo M, Mondola P, Milone A, Gioielli A, Bifulco M. Ascorbate administration to normal and cholesterol-fed rats inhibits in vitro TBARS formation in serum and liver homogenates. Life Sci 1996; 58:1101-8. [PMID: 8614261 DOI: 10.1016/0024-3205(96)00068-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have recently shown that ascorbate has a hypocholesterolemic and hypotriglyceridemic effect on rats fed a diet enriched with 1.5% cholesterol and 25% hydrogenated coconut oil (Nath diet). In this study we evaluated the effect of intraperitoneal ascorbate administration on susceptibility to lipoperoxidation either in rats fed standard or Nath diet. In normal rats ascorbate treatment decreased (p<0.05) the susceptibility to lipoperoxidation induced by incubation of serum for 24 hours with 2.2 mM Cu++, without altering the normal serum fatty acid profile. In rats fed Nath diet we observed a reduced susceptibility of serum to CU++-induced lipoperoxidation (36%), according with their low levels of serum unsaturated fatty acids (40% less than rats fed standard diet). In these animals ascorbate administration affects serum fatty acid profile leading to a decrease of S/U ratio from 1.6 to 1.2 without significantly modifying the susceptibility of serum to lipoperoxidation. Moreover, the production of spontaneous lipid peroxides in liver homogenates, measured as TBARS levels, was strongly inhibited by ascorbate (p<0.01) in rats fed either standard or Nath diet. These data indicate that ascorbate administration exerts an antioxidant effect and that in hypercholesterolemic rats, in addition to a lipid lowering effect, ascorbate exerts a protective role against the peroxidative damage of lipids.
Collapse
Affiliation(s)
- M Santillo
- Dipartimento di Neuroscienze e della Comunicazione Interumana, Sezione Fisiologia, Università di Napoli, Italy
| | | | | | | | | |
Collapse
|
30
|
Abstract
The i.p. injection of the herbicide propanil to male Sprague-Dawley rats increased the susceptibility to lipoperoxidation of liver and brain rat microsomes. A liver damage produced by propanil treatment was demonstrated by decreased serum levels of cholesterol and triglycerides as compared to serum levels of the lipids in control rats. The cellular damage of rat liver was also confirmed by the increased serum levels of aspartate aminotransferase and alkaline phosphatase activities observed in propanil-treated rats as compared to their activities in control rats.
Collapse
Affiliation(s)
- M Santillo
- Istituto di Scienze Fisiologiche Umane, Facoltà di Medicina e Chirurgia, Università di Napoli Federico II, Italy
| | | | | | | | | | | | | |
Collapse
|
31
|
Abstract
Data on circadian rhythms of serum lipids and apolipoproteins in animals and in human subjects are scarce. The goal of this study was to investigate the existence of circadian rhythms in the lipids and apolipoproteins of fasted rats. We showed that in fasted rats well-defined circadian rhythms were present in total serum triglycerides and in cholesterol and triglycerides of very low density lipoprotein (VLDL), intermediate density lipoprotein-low density lipoprotein (IDL-LDL) and high density lipoprotein (HDL). Moreover, our data clearly show that the circadian rhythm of lipoproteins is accompanied by a well defined circadian rhythm of B apoprotein, in all lipoprotein classes examined.
Collapse
Affiliation(s)
- P Mondola
- Istituto di Scienze Fisiologiche Umane, Facoltà di Medicina e Chirurgia, Università di Napoli Federico II, Italy
| | | | | | | | | |
Collapse
|
32
|
Perillo B, Tedesco I, Laezza C, Santillo M, Romano A, Aloj SM, Bifulco M. Regulation of 3-hydroxy-3-methylglutaryl coenzyme A reductase gene expression in FRTL-5 cells. II. Down-regulation by v-K-ras oncogene. J Biol Chem 1995; 270:15237-41. [PMID: 7797508 DOI: 10.1074/jbc.270.25.15237] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity and mRNA levels were significantly reduced in FRTL-5 cells transformed with the Kirsten-Moloney sarcoma virus (KiMol); these cells have lost thyrotropin dependence and express high levels of p21ras. FRTL-5 cells, transformed with a temperature-sensitive mutant of the v-K-ras oncogene (Ats cells: 33 degrees C, permissive; 39 degrees C, nonpermissive), showed significant reduction of HMG-CoA reductase expression when exposed to 33 degrees C. In KiMol cells, as well as in Ats cells at 33 degrees C, the transcription driven by cAMP-responsive element was probed by measuring chloramphenicol acetyl transferase (CAT) levels after transfection with a chimeric plasmid containing the reporter gene linked to the rat reductase promoter. Basal CAT activity in KiMol cells transfected with wild-type promoter was lower than in FRTL-5 cells but was increased by forskolin to the levels attained in thyrotropin-stimulated FRTL-5 cells. Forskolin failed to increase CAT activity in KiMol cells transfected with the plasmid harboring a reductase promoter in which the cAMP-responsive element octamer was mutated to a nonpalindromic sequence. The effect of v-K-ras could be mimicked in FRTL-5 cells by tetradecanoyl phorbol acetate and reverted in KiMol and Ats cells, expressing active Ras protein, by increasing intracellular cAMP and/or by protein kinase C inhibition. The data are consistent with the contention that v-K-ras, through protein kinase C and depletion of intracellular cAMP, is inhibitory for the protein kinase A pathway. This is the first demonstration that active v-K-ras down-regulates HMG-CoA reductase expression.
Collapse
Affiliation(s)
- B Perillo
- Dipartimento di Biologia e Patologia Cellulare e Molecolare L. Califano, Università Federico II, Napoli, Italy
| | | | | | | | | | | | | |
Collapse
|
33
|
Santillo M, Mondola P, Santangelo F, Gioielli A, Iossa S, Basilisco A, De Mercato R. Changes in apoprotein distribution between lipoprotein classes of hypercholesterolemic rats treated with ascorbate. Int J Biochem Cell Biol 1995; 27:257-62. [PMID: 7780829 DOI: 10.1016/1357-2725(94)00082-m] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
It is known that ascorbate has a lipid lowering effect, accompanied by a drop of apo B, in rats fed a diet enriched with 1.5% of cholesterol (Nath diet). In order to better clarify the role exerted by ascorbate in lipid metabolism, the effect of ascorbate administration on apolipoprotein pattern in rats fed the Nath diet was investigated. Wistar male rats fed for two months the Nath diet were treated i.p. with 60 mg/kg of body weight of ascorbate for 10 days. Blood collection before and after the treatment was performed by intracardiac puncture. Lipoproteins were prepared by preparative ultracentrifugation and their apoprotein content was obtained by densitometric scanning of the apoprotein electhrophoretic pattern. The decrease of total plasma cholesterol and triglycerides and of cholesterol, triglycerides and protein content of all plasma lipoproteins observed in ascorbate treated rats, is accompanied by a marked modification of the apolipoprotein pattern of all lipoprotein classes studied, with an increase of apo E content in VLDL-IDL and LDL fractions (135 and 44% respectively), and a decrease of C (37%), AI (70%) and B (37.5%) apoproteins in VLDL-IDL and of apo C (36%) in LDL. On the contrary, in HDL fraction ascorbate induces an increase of C apoproteins (26%) and a decrease of E and B apoproteins (47% and 71% respectively). The data reported clearly show that in hypercholesterolemic rats the lipid lowering effect of ascorbate administration, is accompanied by a marked modification of the apoprotein pattern of all lipoprotein classes studied.
Collapse
Affiliation(s)
- M Santillo
- Istituto di Scienze Fisiologiche Umane, Facoltà di Medicina e Chirurgia, Università degli Studi di Napoli Federico II, Italy
| | | | | | | | | | | | | |
Collapse
|
34
|
Mondola P, Santillo M, Santangelo F, Garbi C, Daniele A. The calf superoxide dismutase receptor of rat hepatocytes. Comp Biochem Physiol Biochem Mol Biol 1994; 108:309-13. [PMID: 8081657 DOI: 10.1016/0305-0491(94)90082-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The presence of a specific SOD surface membrane receptor in rat hepatocyte cells was investigated using ligand blot analysis of the SOD receptor with 125I-SOD, and binding studies with iodinated and fluorescinated SOD. A specific SOD receptor with a molecular weight of about 320 kDa was identified. We suggest that the modulatory role of SOD on HMG-CoA reductase is exerted through this specific receptor.
Collapse
Affiliation(s)
- P Mondola
- Istituto di Scienze Fisiologiche Umane, Facoltà di Medicina e Chirurgia dell'Università di Napoli Federico II, Italy
| | | | | | | | | |
Collapse
|
35
|
Santillo M, Santangelo F, Belfiore A, Mastursi M, Mondola P. Effect of ascorbic acid administration on B and E apoproteins in rats fed a cholesterol enriched diet. Horm Metab Res 1993; 25:156-9. [PMID: 8477953 DOI: 10.1055/s-2007-1002067] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [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: 01/31/2023]
Abstract
The effect of ascorbic acid on cholesterol metabolism is very well documented; it is ascribed to the activation of this vitamin on cholesterol 7 alpha-hydroxylase (EC 1.14) that activates the catabolism of cholesterol. In this paper we have studied the effect of the administration of ascorbic acid on B and E apoproteins of rats fed a diet enriched with 1.5% of cholesterol. The results obtained show that ascorbic acid is able to affect cholesterol metabolism by modifying the serum levels of apo B in total serum and in lipoprotein classes of density less than 1.050 g/ml. Moreover the ascorbic acid treatment reduced the amount of cholesterol and triglycerides in all lipoprotein classes examined. No significant change of total serum apo E was observed following ascorbic acid administration.
Collapse
Affiliation(s)
- M Santillo
- Institute of Human Physiology, Second Faculty of Medicine and Surgery, University of Naples, Italy
| | | | | | | | | |
Collapse
|
36
|
Mondola P, Santillo M, Belfiore A, Camardella L, Santangelo F. The thymus hypocholesterolemic factor (TphF): a bovine thymic superoxide dismutase active on HMG-CoA reductase. Comp Biochem Physiol B 1993; 104:193-9. [PMID: 8448990 DOI: 10.1016/0305-0491(93)90358-c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
1. This work describes the further biochemical characterization of a new calf thymus protein (TphF) and its primary structure. 2. The amino acid sequences, obtained after sequence analysis of peptides derived from the endoproteinase Lys-C digestion, were subjected to a "Protein Data Bank Search" and were found to be identical with regions of bovine superoxide-dismutase (SOD). 3. These data together with those showing the identical electrophoretic migration of SOD and TphF, their same isoelectric point and their immunoreactivity with anti-SOD antibodies, confirm the similarity of these two proteins.
Collapse
Affiliation(s)
- P Mondola
- Istituto di Scienze Fisiologiche Umane II Facoltà di Medicina e Chirurgia di Napoli, Italy
| | | | | | | | | |
Collapse
|
37
|
Mondola P, Santillo M, Santangelo F, Belfiore A, Gambardella P, Bifulco M. Effects of a new calf thymus protein on 3-hydroxy-3-methylglutaryl-CoA reductase activity in rat (Rattus bubalus) hepatocyte cells (BRL-3A). Comp Biochem Physiol B 1992; 103:431-4. [PMID: 1424571 DOI: 10.1016/0305-0491(92)90316-j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. In a previous paper we described the purification steps of a new calf thymus protein able to activate the LDL receptor catabolism. 2. In this paper we examine the modulatory effect of this new calf thymus protein on 3HMG-CoA reductase activity in rat hepatocyte cells to better clarify the role of this protein on cholesterol metabolism. 3. The results obtained show that the calf thymus protein inhibits the HMG-CoA reductase, and support the hypothesis that the activation of LDL receptor catabolism is mediated by a decreased amount of cellular cholesterol following HMG-CoA reductase inhibition.
Collapse
Affiliation(s)
- P Mondola
- Istituto di Scienze Fisiologiche Umane, Università di Napoli, Italy
| | | | | | | | | | | |
Collapse
|
38
|
Mondola P, Santillo M, De Mercato R, Santangelo F. The effect of L-carnitine on cholesterol metabolism in rat (Rattus bubalus) hepatocyte cells. Int J Biochem 1992; 24:1047-50. [PMID: 1397497 DOI: 10.1016/0020-711x(92)90372-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
1. This paper concerns the study of the effect of L-carnitine on cholesterol metabolism in rat hepatocyte cells BRL-3A. In this research the binding of [125I]human low density lipoprotein (LDL) to BRL-3A cells and 3-hydroxy 3-methylglutaryl CoA reductase activity (HMG-CoA reductase activity) after L-carnitine incubation were studied. 2. It was found that L-carnitine is able to increase either the [125I]LDL binding or inhibit the HMG-CoA reductase activity in BRL-3A cells. 3. These results indicate that L-carnitine affects the cholesterol metabolism through an inhibition of HMG-CoA reductase activity that could be responsible for the increased [125I]LDL binding in rat hepatocytes.
Collapse
Affiliation(s)
- P Mondola
- Istituto di Scienze Fisiologiche Umane, II Facoltà di Medicina e Chirurgia, Università di Napoli, Naples, Italy
| | | | | | | |
Collapse
|
39
|
Santillo M, Mondola P, Santangelo F, Belfiore A, Tedesco I, Laezza C, Cerbone R, Romano A, Bifulco M. Characterization of the low density lipoprotein receptor activity in buffalo rat liver (BRL-3A) cells. Comp Biochem Physiol B 1992; 101:489-94. [PMID: 1582187 DOI: 10.1016/0305-0491(92)90032-m] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. BRL-3A cells possess a specific LDL receptor with an apparent mol. wt of 160,000 that binds, with saturation, both human and rat 125I-LDL. 2. Like human fibroblasts, BRL-3A cells also bind, internalize and degrade 125I-hLDL but to a lesser extent. 3. BRL-3A cells also bind the monoclonal antibody against rat liver LDL receptor P1B3. Moreover the LDL receptor activity increases when cells are preincubated with medium containing 5% of LPDS. 4. As with human (h) fibroblasts, treatment of BRL-3A cells with 10(-7) M insulin enhances binding (30%), internalization (18%) and degradation (20%) of 125I-hLDL.
Collapse
Affiliation(s)
- M Santillo
- Istituto di Scienze Fisiologiche Umane, Università di Napoli, Italia
| | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Mondola P, Santillo M, Cammarota L, Santangelo F. Role of a calf thymus preparation in the degradation of native and reductively methylated low density lipoprotein. Int J Biochem 1991; 23:819-21. [PMID: 1773886 DOI: 10.1016/0020-711x(91)90065-u] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
1. The clearance of low density lipoprotein (LDL) is mediated by a specific LDL receptor pathway and by an alternative metabolic pathway that is responsible for the receptor-independent LDL catabolism. 2. This alternative catabolism can be studied in vivo using a preparation of chemically modified LDL that are reductively methylated. 3. Recently we showed that a calf thymus protein extract affects the cholesterol metabolism via activation of LDL catabolism. 4. The aim of this study was to investigate whether in vivo the specific LDL receptor pathway and the independent LDL receptor pathway are affected by thymus treatment. 5. The results obtained injecting in rats native and chemically modified 125I-LDL to probe the receptor independent pathway, show that the thymus gland decreases serum cholesterol by activation of the specific LDL receptor pathway. 6. This effect is mainly evident in liver and kidney that represent organs in which the specific LDL receptors are widely present.
Collapse
Affiliation(s)
- P Mondola
- Istituto di Scienze Fisiologiche Umane, II Facoltà di Medicina e Chirurgia, Università di Napoli, Italia
| | | | | | | |
Collapse
|
41
|
Bifulco M, Santillo M, Tedesco I, Zarrilli R, Laezza C, Aloj SM. Thyrotropin modulates low density lipoprotein binding activity in FRTL-5 thyroid cells. J Biol Chem 1990; 265:19336-42. [PMID: 2229079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
FRTL-5 cells possess high affinity low density lipoprotein (LDL) receptors which bind, internalize, and degrade LDL. When FRTL-5 cells are deprived of thyrotropin (TSH) the binding of LDL increases more than 2-fold. Upon addition of TSH, at a concentration of 1 x 10(-10) M or greater, LDL binding decreases rapidly and within 24 h reaches the level which is typical of FRTL-5 cells chronically stimulated by TSH. The data available suggest that TSH-dependent down-regulation of LDL receptor activity is exerted through a reduction of the number of active LDL receptors, with no change in affinity. It is unlikely that the synthesis of LDL receptors is impaired, since LDL receptor messenger RNA is not decreased by TSH. The effect of the hormone on LDL receptor activity can be mimicked by 8-Br-cAMP and is completely abolished by the protein synthesis inhibitor cycloheximide but not by actinomycin D. TSH regulation of LDL receptor activity is lost in v-ras Ki-transformed FRTL-5 cells (Ki Mol) which also have lost TSH dependence for adenylate cyclase activation and growth. However, 8-Br-cAMP decreases LDL binding in Ki Mol FRTL-5 cells. The reduced availability of LDL receptor in TSH-stimulated FRTL-5 cells may be related to the increased membrane fluidity (Beguinot, F., Beguinot, L., Tramontano, D., Duilio, C., Formisano, S., Bifulco, M., Ambesi-Impiombato, F. S., and Aloj, S. M. (1987) J. Biol. Chem. 262, 1575-1582) or may reflect increased degradation of LDL receptors. We propose that a lower cholesterol uptake is needed in an actively proliferating cell population, to increase the production of isoprenoids whether it be for cholesterol biosynthesis or for the synthesis of other compounds requiring isoprenoid precursors.
Collapse
Affiliation(s)
- M Bifulco
- Centro di Endocrinologia ed Oncologia Sperimentale/Consiglio Nazionale delle Ricerche, University of Naples, Italy
| | | | | | | | | | | |
Collapse
|
42
|
Bifulco M, Santillo M, Tedesco I, Zarrilli R, Laezza C, Aloj SM. Thyrotropin modulates low density lipoprotein binding activity in FRTL-5 thyroid cells. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(17)30663-4] [Citation(s) in RCA: 12] [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: 10/22/2022] Open
|
43
|
Mondola P, Santillo M, Santangelo F, Caporale C, Belfiore A, Bifulco M. Purification and characterization of a calf thymus protein active on lipid metabolism. Int J Biochem 1989; 21:1009-14. [PMID: 2591633 DOI: 10.1016/0020-711x(89)90233-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
1. This work concerns the purification of a calf thymus protein that increases the binding of human 125I-labeled low density lipoprotein (LDL) on both human skin fibroblasts and a special line of rat liver cells, BRL 3A. 2. It was found that the thymus gland affects cholesterol metabolism via an activation of the LDL receptor pathway. 3. Moreover, the thymus protein active on the LDL receptor pathway has a different amino acid composition and molecular weight from other well-characterized thymic peptides.
Collapse
Affiliation(s)
- P Mondola
- Istituto di Scienze Fisiologiche Umane, Università di Napoli, Italia
| | | | | | | | | | | |
Collapse
|
44
|
Mondola P, Santillo M, Tedesco I, Santangelo F, Belfiore A, Bifulco M. Thymus fraction (FIII) effect on cholesterol metabolism: modulation of the low density lipoprotein receptor pathway. Int J Biochem 1989; 21:627-30. [PMID: 2792549 DOI: 10.1016/0020-711x(89)90381-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
1. A heat stable protein fraction from calf thymus is able to determine a marked drop of total serum cholesterol and B apoproteins in rats fed a cholesterol enriched diet. 2. It is known that the catabolism of low density lipoprotein (LDL) cholesterol is mediated by the existence of high affinity surface receptor on membrane cells. 3. The purpose of the present paper is to verify if the heat stable thymus protein fraction is able to affect the LDL receptor pathway in vitro. 4. The results obtained show that the protein calf thymus is able to increase human and rat LDL catabolism.
Collapse
Affiliation(s)
- P Mondola
- Istituto di Scienze Fisiologiche Umane, Università di Napoli, Italia
| | | | | | | | | | | |
Collapse
|
45
|
Mondola P, Belfiore A, Santangelo F, Santillo M. The effect of L-carnitine on the apolipoprotein pattern of rats fed a cholesterol-rich diet. Comp Biochem Physiol B 1988; 89:69-73. [PMID: 3356130 DOI: 10.1016/0305-0491(88)90263-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
1. L-Carnitine was administered to hypercholesterolemic rats for eight days, after which the blood was collected by intracardiac puncture and lipoproteins were collected by preparative ultracentrifuge. 2. The chemical composition of lipoproteins of normal rats and hypercholesterolemic rats before and after L-carnitine treatment was determined. 3. The total serum B and E apoproteins were assayed by rocket electrophoresis, while apoproteins in VLDL, IDL, LDL and HDL were determined by densitometric scanning of SDS and TMU polyacrylamide disc gel electrophoresis. 4. The results obtained showed that the L-carnitine treatment tends to restore to normal values both the chemical composition of lipoproteins and the apoproteins pattern of rats fed on a diet enriched with cholesterol.
Collapse
Affiliation(s)
- P Mondola
- Institute of Physiology, Medical Faculty, Naples University, Italy
| | | | | | | |
Collapse
|
46
|
Mondola P, Santangelo F, Santillo M, Belfiore A, Avallone L, Cifaldi S, d'Angelo A, Pizzuti GP. The serum lipoprotein pattern of water buffalo (Bubalus bubalis). Comp Biochem Physiol B 1987; 88:395-8. [PMID: 3427892 DOI: 10.1016/0305-0491(87)90318-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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
1. The serum lipoprotein pattern of water buffalo was studied by means of electrophoresis and the lipoproteins were isolated by ultracentrifugation on the basis of their hydrated density. 2. High density lipoproteins (HDL) showed a higher level of cholesterol than did the other lipoproteins. Moreover, the level of phospholipids was higher in HDL than in very low density lipoproteins (VLDL). 3. The buffalo B100 apoprotein was similar to that of man and rat. Three apoproteins similar to human apo E, apo AI and AII were found in buffalo HDL, buffalo VLDL contained essentially apo B protein.
Collapse
Affiliation(s)
- P Mondola
- Istituto di Scienze Fisiologiche Umane--II Facoltá di Medicina e Chirurgia, Universitá degli Studi di Napoli, Italy
| | | | | | | | | | | | | | | |
Collapse
|
47
|
de Franciscis P, Greco AM, Gambardella P, Sticchi R, Santangelo F, Santillo M, D'Aponte D. [Circadian oscillations of serotonin and related indoles determined in the hypothalamus of the rat by high performance liquid chromatography]. Boll Soc Ital Biol Sper 1986; 62:1409-16. [PMID: 2437941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
48
|
Mondola P, Santangelo F, Falconi C, Belfiore A, Santillo M. [Effects of a thymus extract on blood levels of apo A and apo B in rats on a hypercholesterolemic diet]. Boll Soc Ital Biol Sper 1986; 62:1457-64. [PMID: 3580179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|