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1.
Aging Clin Exp Res ; 34(9): 1985-1995, 2022 Sep.
Article de Anglais | MEDLINE | ID: mdl-35864304

RÉSUMÉ

Hand osteoarthritis is the most common joint condition and is associated with significant morbidity. It is of paramount importance that patients are thoroughly assessed and examined when complaining of hand stiffness, pain, deformity or disability and that the patient's concerns and expectations are addressed by the healthcare professional. In 2019 the American College of Rheumatology and Arthritis Foundation (ACR/AF) produced guidelines which included recommendations for the treatment of hand osteoarthritis. An ESCEO expert working group (including patients) was convened and composed this paper with the aim to assess whether these guidelines were appropriate for the treatment of hand osteoarthritis therapy in Europe and whether they met with the ESCEO patient-centered approach. Indeed, patients are the key stakeholders in healthcare and eliciting the patient's preference is vital in the context of an individual consultation but also for informing research and policy-making. The patients involved in this working group emphasised the often-neglected area of aesthetic changes in hand osteoarthritis, importance of developing pharmacological therapies which can alleviate pain and disability and the need of the freedom to choose which approach (out of pharmacological, surgical or non-pharmacological) they wished to pursue. Following robust appraisal, it was recommended that the ACR/AF guidelines were suitable for a European context (as described within the body of the manuscript) and it was emphasised that patient preferences are key to the success of individual consultations, future research and future policy-making.


Sujet(s)
Gonarthrose , Europe , Médecine factuelle , Humains , Gonarthrose/thérapie , Soins centrés sur le patient , Orientation vers un spécialiste
2.
Nat Rev Endocrinol ; 18(6): 366-384, 2022 06.
Article de Anglais | MEDLINE | ID: mdl-35484227

RÉSUMÉ

X-linked hypophosphataemia (XLH) is the most frequent cause of hypophosphataemia-associated rickets of genetic origin and is associated with high levels of the phosphaturic hormone fibroblast growth factor 23 (FGF23). In addition to rickets and osteomalacia, patients with XLH have a heavy disease burden with enthesopathies, osteoarthritis, pseudofractures and dental complications, all of which contribute to reduced quality of life. This Consensus Statement presents the outcomes of a working group of the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases, and provides robust clinical evidence on management in XLH, with an emphasis on patients' experiences and needs. During growth, conventional treatment with phosphate supplements and active vitamin D metabolites (such as calcitriol) improves growth, ameliorates leg deformities and dental manifestations, and reduces pain. The continuation of conventional treatment in symptom-free adults is still debated. A novel therapeutic approach is the monoclonal anti-FGF23 antibody burosumab. Although promising, further studies are required to clarify its long-term efficacy, particularly in adults. Given the diversity of symptoms and complications, an interdisciplinary approach to management is of paramount importance. The focus of treatment should be not only on the physical manifestations and challenges associated with XLH and other FGF23-mediated hypophosphataemia syndromes, but also on the major psychological and social impact of the disease.


Sujet(s)
Rachitisme hypophosphatémique familial , Facteur-23 de croissance des fibroblastes , Arthrose , Syndrome cachectique , Adulte , Animaux , Rachitisme hypophosphatémique familial/diagnostic , Rachitisme hypophosphatémique familial/traitement médicamenteux , Rachitisme hypophosphatémique familial/génétique , Rachitisme hypophosphatémique familial/métabolisme , Facteur-23 de croissance des fibroblastes/métabolisme , Humains , Arthrose/diagnostic , Arthrose/traitement médicamenteux , Arthrose/génétique , Arthrose/métabolisme , Qualité de vie , Syndrome cachectique/diagnostic , Syndrome cachectique/traitement médicamenteux , Syndrome cachectique/génétique , Syndrome cachectique/métabolisme
3.
Aging Clin Exp Res ; 34(4): 695-714, 2022 Apr.
Article de Anglais | MEDLINE | ID: mdl-35332506

RÉSUMÉ

Osteoporosis care has evolved markedly over the last 50 years, such that there are now an established clinical definition, validated methods of fracture risk assessment and a range of effective pharmacological agents. Currently, bone-forming (anabolic) agents, in many countries, are used in those patients who have continued to lose bone mineral density (BMD), patients with multiple subsequent fractures or those who have fractured despite treatment with antiresorptive agents. However, head-to-head data suggest that anabolic agents have greater rapidity and efficacy for fracture risk reduction than do antiresorptive therapies. The European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) convened an expert working group to discuss the tools available to identify patients at high risk of fracture, review the evidence for the use of anabolic agents as the initial intervention in patients at highest risk of fracture and consider the sequence of therapy following their use. This position paper sets out the findings of the group and the consequent recommendations. The key conclusion is that the current evidence base supports an "anabolic first" approach in patients found to be at very high risk of fracture, followed by maintenance therapy using an antiresorptive agent, and with the subsequent need for antiosteoporosis therapy addressed over a lifetime horizon.


Sujet(s)
Anabolisants , Agents de maintien de la densité osseuse , Ostéoporose , Fractures ostéoporotiques , Anabolisants/pharmacologie , Anabolisants/usage thérapeutique , Densité osseuse , Agents de maintien de la densité osseuse/usage thérapeutique , Humains , Ostéoporose/complications , Ostéoporose/traitement médicamenteux , Fractures ostéoporotiques/traitement médicamenteux , Fractures ostéoporotiques/prévention et contrôle
4.
Folia Med (Plovdiv) ; 63(3): 385-391, 2021 Jun 30.
Article de Anglais | MEDLINE | ID: mdl-34196140

RÉSUMÉ

AIM: The objective of the present study was to make a complex evaluation of behaviour, lipid metabolism, inflammation, and bone turnover in an ovariectomized rat model used to simulate postmenopausal clinical findings. MATERIALS AND METHODS: Female Wistar rats were divided into 2 groups of 16 animals each: sham operated (SO) animals and ovariectomized (OVX) animals. Three months after the operation, a battery of behavioural tests was performed including an open field test (OFT), elevated pus-maze test (EPM), the social interaction test (SIT), the forced swim test (FST), and a hot plate test (HPT). At termination of experiment, weight gain and fat deposits (total and retroperitoneal) were measured. Serum concentrations of blood lipids were determined. Tumor necrosis factor alpha (TNF-alpha) and alkaline phosphatase (ALP) serum concentrations were used for evaluation of the inflammation and bone turnover, respectively. Femur bone mineral density (BMD) was evaluated using dual energy X-ray absorptiometry. RESULTS: OVX rats did not demonstrate any significant behavioural changes in OFT and EPM tests but showed a decreased interaction time in SIT and an increased immobility time in FST test which indicated anxiety and depression. The OVX rats had a significantly lower pain sensitivity threshold. They had greater weight gain, increased total and retroperitoneal fat deposits, as well as elevated total fat/body weight and retroperitoneal fat/body weight ratios. Blood cholesterol, ALP and TNF-alpha of the OVX group were also significantly higher. Femur BMD of OVX rats was slightly but not significantly reduced. CONCLUSIONS: Estrogen deficiency in OVX rats caused depression, anxiety, hyperalgesia, obesity, dyslipidemia, and inflammation before the reduction in bone mineral density was prominent.


Sujet(s)
Densité osseuse , Métabolisme lipidique , Animaux , Poids , Oestrogènes , Femelle , Inflammation , Ovariectomie , Rats , Rat Wistar , Facteur de nécrose tumorale alpha , Prise de poids
5.
Aging Clin Exp Res ; 33(1): 3-17, 2021 Jan.
Article de Anglais | MEDLINE | ID: mdl-32737844

RÉSUMÉ

BACKGROUND: In 2016, an expert working group was convened under the auspices of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO) and formulated consensus recommendations for the conduct of clinical trials for drugs to prevent or treat sarcopenia. AIMS: The objective of the current paper is to provide a 2020 update of the previous recommendations in accordance with the evidence that has become available since our original recommendations. METHODS: This paper is based on literature reviews performed by members of the ESCEO working group and followed up with face to face meetings organized for the whole group to make amendments and discuss further recommendations. RESULTS: The randomized placebo-controlled double-blind parallel-arm drug clinical trials should be the design of choice for both phase II and III trials. Treatment and follow-up should run at least 6 months for phase II and 12 months for phase III trials. Overall physical activity, nutrition, co-prescriptions and comorbidity should be recorded. Participants in these trials should be at least 70-years-old and present with a combination of low muscle strength and low physical performance. Severely malnourished individuals, as well as bedridden patients, patients with extremely limited mobility or individuals with physical limitations clearly attributable to the direct effect of a specific disease, should be excluded. Multiple outcomes are proposed for phase II trials, including, as example, physical performance, muscle strength and mass, muscle metabolism and muscle-bone interaction. For phase III trials, we recommend a co-primary endpoint of a measure of functional performance and a Patient Reported Outcome Measure. CONCLUSION: The working group has formulated consensus recommendations on specific aspects of trial design, and in doing so hopes to contribute to an improvement of the methodological robustness and comparability of clinical trials. Standardization of designs and outcomes would advance the field by allowing better comparison across studies, including performing individual patient-data meta-analyses, and different pro-myogenic therapies.


Sujet(s)
Arthrose , Ostéoporose , Préparations pharmaceutiques , Sarcopénie , Sujet âgé , Humains , Force musculaire , Sarcopénie/traitement médicamenteux
6.
Adv Ther ; 36(10): 2811-2824, 2019 10.
Article de Anglais | MEDLINE | ID: mdl-31440982

RÉSUMÉ

INTRODUCTION: Increased biochemical bone turnover markers (BTMs) measured in serum are associated with bone loss, increased fracture risk and poor treatment adherence, but their role in clinical practice is presently unclear. The aim of this consensus group report is to provide guidance to clinicians on how to use BTMs in patient evaluation in postmenopausal osteoporosis, in fracture risk prediction and in the monitoring of treatment efficacy and adherence to osteoporosis medication. METHODS: A working group with clinical scientists and osteoporosis specialists was invited by the Scientific Advisory Board of European Society on Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO). RESULTS: Serum bone formation marker PINP and resorption marker ßCTX-I are the preferred markers for evaluating bone turnover in the clinical setting due to their specificity to bone, performance in clinical studies, wide use and relatively low analytical variability. BTMs cannot be used to diagnose osteoporosis because of low sensitivity and specificity, but can be of value in patient evaluation where high values may indicate the need to investigate some causes of secondary osteoporosis. Assessing serum levels of ßCTX-I and PINP can improve fracture prediction slightly, with a gradient of risk of about 1.2 per SD increase in the bone marker in addition to clinical risk factors and bone mineral density. For an individual patient, BTMs are not useful in projecting bone loss or treatment efficacy, but it is recommended that serum PINP and ßCTX-I be used to monitor adherence to oral bisphosphonate treatment. Suppression of the BTMs greater than the least significant change or to levels in the lower half of the reference interval in young and healthy premenopausal women is closely related to treatment adherence. CONCLUSION: In conclusion, the currently available evidence indicates that the principal clinical utility of BTMs is for monitoring oral bisphosphonate therapy.


Sujet(s)
Algorithmes , Marqueurs biologiques/sang , Agents de maintien de la densité osseuse/usage thérapeutique , Densité osseuse/effets des médicaments et des substances chimiques , Remodelage osseux/effets des médicaments et des substances chimiques , Diphosphonates/usage thérapeutique , Ostéoporose post-ménopausique/traitement médicamenteux , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Études de suivi , Humains , Adulte d'âge moyen , Valeurs de référence , Résultat thérapeutique
7.
Ageing Res Rev ; 55: 100946, 2019 11.
Article de Anglais | MEDLINE | ID: mdl-31437484

RÉSUMÉ

The prevalence of osteoarthritis (OA) increases not only because of longer life expectancy but also because of the modern lifestyle, in particular physical inactivity and diets low in fiber and rich in sugar and saturated fats, which promote chronic low-grade inflammation and obesity. Adverse alterations of the gut microbiota (GMB) composition, called microbial dysbiosis, may favor metabolic syndrome and inflammaging, two important components of OA onset and evolution. Considering the burden of OA and the need to define preventive and therapeutic interventions targeting the modifiable components of OA, an expert working group was convened by the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) to review the potential contribution of GMB to OA. Such a contribution is supported by observational or dietary intervention studies in animal models of OA and in humans. In addition, several well-recognized risk factors of OA interact with GMB. Lastly, GMB is a critical determinant of drug metabolism and bioavailability and may influence the response to OA medications. Further research targeting GMB or its metabolites is needed to move the field of OA from symptomatic management to individualized interventions targeting its pathogenesis.


Sujet(s)
Microbiome gastro-intestinal , Arthrose/microbiologie , Animaux , Dysbiose , Europe , Humains , Inflammation , Maladies ostéomusculaires/économie , Maladies ostéomusculaires/microbiologie , Obésité , Arthrose/économie , Ostéoporose/économie , Ostéoporose/microbiologie , Sociétés médicales
8.
Calcif Tissue Int ; 105(2): 125-126, 2019 Aug.
Article de Anglais | MEDLINE | ID: mdl-31338562

RÉSUMÉ

The original version of this article unfortunately contained a mistake in one of the co-author's name. The co-author Cyrus Cooper's degree "FMedSci" was incorrectly tagged as family name. This has been corrected with this erratum.

9.
Calcif Tissue Int ; 105(2): 109-124, 2019 08.
Article de Anglais | MEDLINE | ID: mdl-31098729

RÉSUMÉ

The co-existence of impaired bone health (osteopenia/osteoporosis), reduced muscle mass and strength (sarcopenia), and increased adiposity (obesity) in middle-aged and older people has been identified in recent studies, leading to a proposal for the existence of "osteosarcopenic obesity" as a distinct entity. Evidence for the pathophysiological overlap of these conditions is mounting, although a causal relationship is yet to be established. Each component condition occurs frequently with increasing age, and with shared risk factors in many instances, thus, an overlap of these three conditions is not surprising. However, whether the concurrent existence of sarcopenia, osteoporosis and obesity leads to an increased risk of adverse musculoskeletal outcomes and mortality above and beyond the risks associated with the sum of the component parts remains to be proven and is a question of research interest. In this article, we review evidence for the existence of osteosarcopenic obesity including the current operational definition of osteosarcopenic obesity, prevalence, pathophysiology, outcomes and exploratory approaches to the management of components. We conclude that, there is insufficient evidence to support a discrete clinical entity of osteosarcopenic obesity at this time. To expand knowledge and understanding in this area, there is a need for consensus on a definition of osteosarcopenic obesity which will allow for identification, further epidemiological studies and comparisons between studies. Additionally, studies should assess whether the clinical outcomes associated with osteosarcopenic obesity are worse than the mere addition of those linked with its components. This will help to determine whether defining a person as having this triad will eventually result in a more effective treatment than addressing each of the three conditions separately.


Sujet(s)
Obésité/classification , Obésité/physiopathologie , Sarcopénie/classification , Sarcopénie/physiopathologie , Tissu adipeux/métabolisme , Adiposité , Inhibiteurs de l'enzyme de conversion de l'angiotensine , Exercice physique , Traitement par les exercices physiques , Femelle , Microbiome gastro-intestinal , Ghréline/antagonistes et inhibiteurs , Humains , Mâle , Myostatine/antagonistes et inhibiteurs , Obésité/complications , Ostéoporose , Prévalence , Récepteurs aux androgènes/métabolisme , Facteurs de risque , Sarcopénie/complications , Graisse sous-cutanée/métabolisme , Testostérone/métabolisme , Résultat thérapeutique
10.
Aging Clin Exp Res ; 31(7): 905-915, 2019 Jul.
Article de Anglais | MEDLINE | ID: mdl-30993659

RÉSUMÉ

There is increasing emphasis on patient-centred research to support the development, approval and reimbursement of health interventions that best meet patients' needs. However, there is currently little guidance on how meaningful patient engagement may be achieved. An expert working group, representing a wide range of stakeholders and disciplines, was convened by the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) and the World Health Organization (WHO). Through a structured, collaborative process the group generated practical guidance to facilitate optimal patient engagement in clinical development and regulatory decisions. Patient engagement is a relational process. The principles outlined in this report were based on lessons learned through applied experience and on an extensive dialogue among the expert participants. This practice guidance forms a starting point from which tailoring of the approach to suit different chronic diseases may be undertaken.


Sujet(s)
Arthrose , Ostéoporose , Participation des patients , Consensus , Recherche sur les services de santé/organisation et administration , Humains , Arthrose/traitement médicamenteux , Arthrose/économie , Ostéoporose/traitement médicamenteux , Ostéoporose/économie , Guides de bonnes pratiques cliniques comme sujet , Sociétés médicales , Organisation mondiale de la santé
11.
Semin Arthritis Rheum ; 49(1): 9-19, 2019 08.
Article de Anglais | MEDLINE | ID: mdl-30712918

RÉSUMÉ

OBJECTIVES: Type 2 diabetes mellitus (T2DM) and osteoarthritis (OA) are common diseases that frequently co-exist, along with overweight/obesity. While the mechanical impact of excess body weight on joints may explain lower limb OA, we sought to explore whether T2DM is linked to OA outside of excess weight and whether T2DM may play a role in OA pathophysiology. The consequence of T2DM on OA outcomes is a question of research interest. METHODS: We conducted a critical review of the literature to explore the association between T2DM and OA, whether any association is site-specific for OA, and whether the presence of T2DM impacts on OA outcomes. We also reviewed the literature to assess the safety of anti-OA treatments in patients with T2DM. RESULTS: T2DM has a pathogenic effect on OA through 2 major pathways involving oxidative stress and low-grade chronic inflammation resulting from chronic hyperglycemia and insulin resistance. T2DM is a risk factor for OA progression and has a negative impact on arthroplasty outcomes. Evidence is mounting for safety concerns with some of the most frequently prescribed anti-OA medications, including paracetamol, non-steroidal anti-inflammatory drugs, and corticosteroid injections, while other anti-OA medications may be safely prescribed in OA patients with T2DM, such as glucosamine and intra-articular hyaluronic acid. CONCLUSIONS: Future research is needed to better understand whether diabetes control and prevention can modulate OA occurrence and progression. The selection of therapy to treat OA symptoms in patients with T2DM may require careful consideration of the evidence based to avoid untoward safety issues.


Sujet(s)
Diabète de type 2/complications , Obésité/complications , Arthrose/complications , Diabète de type 2/métabolisme , Évolution de la maladie , Humains , Insulinorésistance/physiologie , Obésité/métabolisme , Arthrose/métabolisme
12.
Biotechnol Biotechnol Equip ; 29(1): 92-100, 2015 Jan 02.
Article de Anglais | MEDLINE | ID: mdl-26019621

RÉSUMÉ

Opioid and non-opioid effects of acute and chronic morphine administration on behaviour, cardiovascular responses, cell proliferation and apoptosis and nitric-oxide synthase (NOS) activity were studied in rats. A novel score-point scale was introduced to quantify the signs of opioid withdrawal syndrome. NOS inhibitor L-NAME (NG-nitro-L-arginine methyl ester) was applied to reveal the role of NOS/NO pathway in the modulation of morphine-induced in vivo and in vitro responses. The obtained data showed that chronic co-administration of L-NAME drastically attenuated naloxone-precipitated withdrawal syndrome and prevented the development of morphine tolerance to cardiovascular action of morphine. The apoptotic process was very much restricted by L-NAME supplementation of chronic morphine treatment, which resulted in few apoptotic cells, less low molecular weight genomic DNA and preservation of high molecular weight non-fragmented genomic DNA. The study provides new data for nitroxidergic modulation of opioid tolerance and dependence.

13.
Curr Pharm Biotechnol ; 16(5): 414-23, 2015.
Article de Anglais | MEDLINE | ID: mdl-25543689

RÉSUMÉ

Treatment of osteoporosis remains a therapeutic challenge. The effect of Apium Nodiflorum extract on development of experimental osteoporosis, pain thresholds and carrageenan-induced inflammation has been studied in ovariectomized osteoporotic Wistar rats. After osteoporosis verification rats were randomized and received vehicle only, HPLC-standardized Apium extract (equal to 2.4 mg/kg Quercetin) or Genistein (2.5 mg/kg) for 8 weeks. To verify the effect of Apium on the development of osteoporosis, bone mineral density (BMD) and bone mineral content (BMC), bone histology and plasma levels of IL-6 and RANKL were measured 6 months after ovariectomy and 8 weeks after treatment with Apium extract or Genistein as comparator. Inflammatory hyperalgesia was induced by intraplantar injection of 1% Carrageenan. Apium extract and Genistein impeded the development of osteoporosis (significant differences were shown for BMC and BMD levels in drug vs. vehicle treated rats) and improved bone histology and histological score. Apium and Genistein decreased IL-6 level. Both treatments alleviated mechanical hyperalgesia, decreased exudative reaction and lowered inflammatory pain threshold. The results suggested that Apium extract could be an alternative therapy for post-menopausal osteoporosis.


Sujet(s)
Anti-inflammatoires/usage thérapeutique , Apiaceae , Ostéoporose/traitement médicamenteux , Extraits de plantes/usage thérapeutique , Animaux , Anti-inflammatoires/pharmacologie , Densité osseuse/effets des médicaments et des substances chimiques , Carragénane , Femelle , Fémur/effets des médicaments et des substances chimiques , Fémur/métabolisme , Fémur/anatomopathologie , Flavonoïdes/analyse , Génistéine/pharmacologie , Hyperalgésie/traitement médicamenteux , Inflammation/induit chimiquement , Inflammation/traitement médicamenteux , Interleukine-6/sang , Ostéoporose/sang , Ostéoporose/métabolisme , Ostéoporose/anatomopathologie , Ovariectomie , Phénols/analyse , Extraits de plantes/composition chimique , Extraits de plantes/pharmacologie , Ligand de RANK/sang , Rat Wistar , Tibia/effets des médicaments et des substances chimiques , Tibia/métabolisme , Tibia/anatomopathologie
14.
Ann Biomed Eng ; 36(6): 947-57, 2008 Jun.
Article de Anglais | MEDLINE | ID: mdl-18330704

RÉSUMÉ

The arterial wall viscoelasticity plays an essential role in the vascular responsiveness to vasoactive drugs or pathologies. The aim of this investigation was to derive and compare resonance curve (RC), natural frequency (f(0)), dynamic modulus of elasticity (E'), and coefficient of viscosity (beta) of (i) vital and devitalized preparations of rat thoracic and abdominal aorta, (ii) human arterial prostheses, and to study the histomorphology of vital and devitalized rat aorta. The method of low frequency forced oscillations was employed. RC of vital preparations showed a hardening type of elasticity whereas in devitalized preparations it was of softening type. E' increased nonlinearly, f(0) decreased and beta increased linearly with equivalent intraluminal pressure (p(eqi)). Distensibility of abdominal aorta was lower than thoracic aorta. Distensibility decreased with increasing p(eqi). E', f(0), and beta increased significantly after devitalization. It was suggested that postmortem viscoelastic characteristics should not be used directly to specify the vital arteries viscoelasticity. RC of human prostheses showed a softening type of elasticity. Arterial prostheses have low circumferential distensibility with E'-values higher than reported in the literature for human arteries. The method of forced oscillations could be employed for studying the arterial wall biomechanics and viscoelasticity of arterial prostheses.


Sujet(s)
Aorte/physiologie , Bioprothèse , Prothèse vasculaire , Conception assistée par ordinateur , Modèles cardiovasculaires , Animaux , Aorte/transplantation , Système acellulaire , Simulation numérique , Élasticité , Analyse de panne d'appareillage , Humains , Techniques in vitro , Mâle , Conception de prothèse , Rats , Rat Wistar , Viscosité
15.
FASEB J ; 20(12): 2124-6, 2006 Oct.
Article de Anglais | MEDLINE | ID: mdl-16966485

RÉSUMÉ

The classical view postulates that neuropeptide precursors in neurons are processed into mature neuropeptides in the somatic trans-Golgi network (TGN) and in secretory vesicles during axonal transport. Here we show that prodynorphin (PDYN), precursor to dynorphin opioid peptides, is predominantly located in axon terminals and dendrites in hippocampal and striatal neurons. The molar content of unprocessed PDYN was much greater than that of dynorphin peptides in axon terminals of PDYN-containing neurons projecting to the CA3 region of the hippocampus and in the striatal projections to the ventral tegmental area. Electron microscopy showed coexistence of PDYN and dynorphins in the same axon terminals with occasional codistribution in individual dense core vesicles. Thus, the precursor protein is apparently stored at presynaptic sites. In comparison with the hippocampus and striatum, PDYN and dynorphins were more equally distributed between neuronal somata and processes in the amygdala and cerebral cortex, suggesting regional differences in the regulation of trafficking and processing of the precursor protein. Potassium-induced depolarization activated PDYN processing and secretion of opioid peptides in neuronal cultures and in a model cell line. Regulation of PDYN storage and processing at synapses by neuronal activity or extracellular stimuli may provide a local mechanism for regulation of synaptic transmission.


Sujet(s)
Dendrites/métabolisme , Enképhalines/métabolisme , Terminaisons présynaptiques/métabolisme , Précurseurs de protéines/métabolisme , Animaux , Noyaux gris centraux/cytologie , Encéphale/cytologie , Cellules cultivées , Enképhalines/analyse , Hippocampe/cytologie , Mâle , Potentiels de membrane/physiologie , Microscopie électronique , Neurones/ultrastructure , Précurseurs de protéines/analyse , Rats , Rat Sprague-Dawley , Distribution tissulaire
16.
Eur J Med Chem ; 38(7-8): 687-94, 2003.
Article de Anglais | MEDLINE | ID: mdl-12932899

RÉSUMÉ

A series of analogues of nociceptin, Noc(1-13)NH(2) (an agonist at the ORL1 receptor) was synthesized with following modifications: (1) N-terminal extension with Arg(0); (2) replacement of Gly(3) by basic or polar amino acids-Arg, Asn, Lys(For) or deletion; (3) exchange of Phe(1) or Phe(4) by Phe(NO(2)); (4) substitution of Ser(10) with D-Ser, Pro, D-Pro. The analogs were synthesized by solid-phase methodology using Fmoc-amino acid pentafluorophenyl esters. The affinity for the ORL1 and for the kappa, micro and delta-opioid receptors was investigated by radioligand binding assay and bioactivity by a mouse vas deferens (MVD) assay. The addition of the amino acid residue Arg to the N-terminal enhances the opioid receptor affinity of Noc(1-13)NH(2) while retaining ORL1 receptor affinity at a moderate level. The replacement of Gly in position 3 by the basic or polar amino acids-Arg, Asn, Lys(For) or its deletion led to inactive analogues. The replacement of Ser in position 10 by its D-isomer, Pro and D-Pro resulted in a series of analogues with the following order of activity: Ser(10)>D-Ser(10)>Pro(10)>D-Pro(10). In [D-Ser(10)]Noc(1-13)NH(2), introduction of an additional Phe(NO(2))(4) led to a >60-fold increase of ORL1 affinity, completely attenuating the loss of affinity brought about by Ser(10). In other analogues, introduction of Phe(NO(2))(4) did not change the magnitude of ORL1 binding significantly. Generally, while modifications in position 3 frequently led to a loss of most or all bioactivity, modifications in position 0 (Arg(0)) or 4 (Phe(NO(2))(4)) and 10 (D-Ser(10), Pro(10)) are tolerated.


Sujet(s)
Peptides opioïdes/composition chimique , Fragments peptidiques/composition chimique , Récepteurs aux opioïdes/agonistes , Substitution d'acide aminé , Animaux , Sites de fixation , Ligands , Mâle , Souris , Peptides opioïdes/synthèse chimique , Peptides opioïdes/pharmacologie , Fragments peptidiques/synthèse chimique , Fragments peptidiques/pharmacologie , Dosage par compétition , Récepteurs aux opioïdes/composition chimique , Récepteurs aux opioïdes/métabolisme , Relation structure-activité , Conduit déférent/effets des médicaments et des substances chimiques , Conduit déférent/métabolisme ,
17.
Br J Pharmacol ; 135(3): 800-6, 2002 Feb.
Article de Anglais | MEDLINE | ID: mdl-11834628

RÉSUMÉ

The effects of nociceptin/orphanin (N/OFQ) and the selective ORL1 antagonist J-113397 (1-[(3R,4R)-1-cyclo-octylmethyl-3-hydroxymethyl-4-piperidyl]-3-ethyl-1,3-dihydro-2H-benzimidazol-2-one) were studied on electrically-evoked release of [(3)H]-noradrenaline ([(3)H]-NA) from human and rat neocortical slices. Specimens of human tissue were obtained during neurosurgery. Slices were preincubated with 0.1 microM [(3)H]-NA, superfused in the presence of desipramine, idazoxan, and naloxone (1 microM each), and stimulated electrically up to three times under conditions (4 pulses, 100 Hz, 2 ms, 60 mA) that prevent inhibition of evoked [(3)H]-NA release by endogenous modulators accumulating during ongoing stimulation. N/OFQ decreased electrically-evoked [(3)H]-NA release in both human and rat neocortical slices in a concentration-dependent manner. The respective pEC(50) values were 7.74 [CI(95): 7.47, 8.04] and 7.64 [CI(95): 7.48, 7.77], and the maximal inhibitions were 36.9% [CI(95): 32.4%, 41.8%] and 66.4% [CI(95): 61.7%, 72.7%]. N/OFQ (1 microM) inhibited K(+) (15 mM)-evoked [(3)H]-NA release from neocortical slices of both species by a similar magnitude, either in the presence or absence of tetrodotoxin. The nonpeptide ORL1 antagonist J-113397 competitively attenuated, with similar potency, the inhibition of electrically-evoked [(3)H]-NA release by N/OFQ in both species (pA(2) values: human, 8.16 [CI(95): 7.64, 8.64]; rat, 8.47 [CI(95): 8.27, 8.67]). J-113397 (0.1 microM) by itself did not alter either the evoked or spontaneous [(3)H]-NA release, suggesting that presynaptic ORL1 receptors are not activated by endogenous N/OFQ under the stimulation conditions employed. This study provides the first evidence that N/OFQ modulates [(3)H]-NA release in human neocortex via specific ORL1 receptors most likely located on noradrenergic axon terminals.


Sujet(s)
Néocortex/métabolisme , Norépinéphrine/antagonistes et inhibiteurs , Norépinéphrine/métabolisme , Récepteurs aux opioïdes/physiologie , Adolescent , Adulte , Animaux , Benzimidazoles/pharmacologie , Enfant , Relation dose-effet des médicaments , Stimulation électrique/méthodes , Femelle , Humains , Mâle , Adulte d'âge moyen , Antagonistes narcotiques/pharmacologie , Néocortex/effets des médicaments et des substances chimiques , Peptides opioïdes/pharmacologie , Pipéridines/pharmacologie , Rats , Rat Wistar , Récepteurs aux opioïdes/agonistes , ,
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