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1.
J Prev Alzheimers Dis ; 11(3): 730-738, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38706289

RESUMEN

BACKGROUND: Serum-measured fragments of Tau cleaved by ADAM-10 (Tau-A) and Caspase-3 (Tau-C) have been found linked to change in cognitive function and risk of dementia. OBJECTIVES: 1) To determine the discriminatory abilities of Tau-A, and Tau-C in subjects with either mild cognitive impairment (MCI) due to Alzheimer's disease (AD) or AD dementia compared to a control group. 2) To determine if there is a relation between Tau-A, and Tau-C and established cerebrospinal fluid (CSF) markers of AD- ß-Amyloid1-42 (AB42), Phosphorylated-tau-181 (p-tau), and total-tau. 3) To determine if Tau-A and Tau-C are associated with progression rate from MCI due to AD to AD dementia. DESIGN: Cross-sectional and a substudy using a retrospective cohort design. SETTING: Memory clinic derived subjects contributing to the Danish Dementia Biobank. PARTICIPANTS: Cognitively unimpaired subjects (n=49), patients with mild cognitive impairment (MCI) due to AD (n=45), and Alzheimer's dementia (n=52). MEASUREMENTS: Competitive enzyme-linked immunosorbent assay (ELISA)-measured serum levels of Tau-A, and Tau-C. RESULTS: The ratio between Tau-A and Tau-C differed between the three groups (p=0.015). Age- and sex-adjusted Tau-A differed between groups with lower ratios being associated with more severe disease (p=0.023). Tau-C was trending towards significant correlation to CSF-levels of AB42 (Pearson correlation coefficient 0.164, p=0.051). Those with Tau-C-levels in the 2nd quartile had a hazard ratio (HR) of 2.91 (95% CI 1.01 - 8.44, p=0.04) of progression compared to those in the 1st quartile. Those in the 3rd quartile was found to have a borderline significant (p=0.055) HR of 2.63 (95% CI 0.98 - 7.05) when compared to those in the lowest quartile. CONCLUSIONS: Tau-A and the ratio between Tau-A and Tau-C showed significant differences between groups and were correlated to CSF-AB42. Tau-C values in the middle range were associated with faster progression from MCI to dementia. This pilot study adds to the mounting data suggesting serum-measured Tau-A and Tau-C as biomarkers useful in relation to diagnosis and progression rate in AD but need further validation.


Asunto(s)
Enfermedad de Alzheimer , Biomarcadores , Disfunción Cognitiva , Progresión de la Enfermedad , Proteínas tau , Humanos , Proteínas tau/sangre , Proteínas tau/líquido cefalorraquídeo , Disfunción Cognitiva/sangre , Disfunción Cognitiva/diagnóstico , Masculino , Femenino , Anciano , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Estudios Transversales , Estudios Retrospectivos , Persona de Mediana Edad , Péptidos beta-Amiloides/sangre , Péptidos beta-Amiloides/líquido cefalorraquídeo , Demencia/sangre , Estudios de Cohortes , Fragmentos de Péptidos/sangre , Fragmentos de Péptidos/líquido cefalorraquídeo
2.
J Prev Alzheimers Dis ; 10(3): 536-542, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37357295

RESUMEN

BACKGROUND: Disease modifying treatments for dementia are only just surfacing, and their development is still significantly hindered by the lack of validated tools for identification of subjects with subclinical disease. Much interest has been taken in developing accessible non-invasive serum biomarkers of neurodegeneration. Recent studies have identified caspase-3-cleaved tau (Tau-C), and ADAM-10 cleaved tau (Tau-A) as possible markers of preclinical neurodegenerative disease. OBJECTIVES: To explore if serum levels of Tau-A and Tau-C change as a consequence of neurodegeneration. DESIGN AND SETTING: Cohort study with measurement of biomarkers and genome sequencing at baseline with follow-up after an average of 14 years. PARTICIPANTS: Postmenopausal Danish women from the Prospective Epidemiological Risk Factor (PERF) cohort (n=4968) Methods: Genotyping data was used to perform a Mendelian randomization analysis of serum levels of Tau-A and Tau-C in relation to a diagnosis of dementia at follow-up. A dementia diagnosis was defined as a composite of an all-cause dementia diagnosis derived from the Danish National Health registries, a self-reported diagnosis of dementia and/or cognitive test scores suggestive of dementia. Serum levels of Tau-A and Tau-C were measured blinded in samples from baseline in a CAP certified lab. The association with dementia was assessed using bi-directional one- and two- sample Mendelian randomization. RESULTS: A lead single nucleotide polymorphism (SNP) was identified for Tau-A (rs10414043) and Tau-C (rs429358), respectively were identified. Both were located in the APOE/C1 cluster on chromosome 19. APOE and EPOC1 variants were associated with lower levels of Tau-A and Tau-C levels - effect size -0.13, 95%CI [-0.17 - -0.09] log2 (ng/mL), p=7.05e-11 for rs10414043 association with Tau-A and effect size -0.12, 95%CI [-0.15 - -0.08] log2 (ng/mL), p=2e-11 for rs429358 association with Tau-C. When incorporating genetic data from a larger genetic study we found that Alzheimer's disease was marginally associated with a decreased Tau-A and Tau-C levels (Odds Ratio 0.97, 95%CI [0.93 - 1.00]. No association was found in the forward Mendelian randomization analysis. CONCLUSIONS: By combining genotype data with serum measurements of the novel biomarkers Tau-A and Tau-C, we conclude that Tau-A and Tau-C levels change because of neurodegeneration. We also conclude that lower serum-values of the biomarkers are associated with the presence of genetic variants commonly found in individuals suffering from late-onset Alzheimer's Dementia. These findings add to the growing data pointing towards Tau-A and Tau-C as valuable biomarkers for neurodegeneration.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Humanos , Femenino , Estudios de Cohortes , Péptidos beta-Amiloides , Enfermedades Neurodegenerativas/diagnóstico , Enfermedades Neurodegenerativas/genética , Proteínas tau/genética , Estudios Prospectivos , Análisis de la Aleatorización Mendeliana , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/genética , Biomarcadores , Apolipoproteínas E/genética
3.
Biomed Pharmacother ; 156: 113842, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36242844

RESUMEN

Cagrilintide is a novel long-acting amylin receptor agonist, which has shown a potent induction of weight loss. Interestingly, cagrilintide is a Dual Amylin and Calcitonin Receptor Agonist (DACRA) derived from an amylin backbone. Another class of long-acting DACRAs exists, namely the KBPs. These are salmon calcitonin-based and have shown preclinical potential; however, how and if they differentiate from amylin-derived molecules remain to be studied. Here, we compare cagrilintide to the DACRA KBP-336 with respect to receptor activation balance in vitro and using metabolic in vivo models. Peptide potencies were assessed using receptor-specific assays in vitro and in vivo. In vivo efficacies on body weight and glucose homeostasis were investigated head-to-head in high-fat diet (HFD) fed obese and T2D (ZDF) rat models. Both peptides activate the amylin and the calcitonin receptor in vitro and in vivo, with KBP-336 being more potent, and showing a CTR bias. KBP-336 and cagrilintide induced a potent and dose-dependent weight loss in HFD rats, with the highest dose of KBP-336 being superior to cagrilintide. In diabetic ZDF rats, DACRA treatment improved fasting blood glucose, HbA1c levels, and insulin action, with KBP-336 being superior to cagrilintide in improving glucose control. In summary, both KBP-336 and cagrilintide are DACRAs, however with KBP-336 being biased towards the CTR resulting in a different receptor activation balance. Interestingly, KBP-336 showed superior long-term efficacy on both weight loss and glucose control, supporting relevance of the receptor balance, and highlighting KBP-336 as a promising agent for the treatment of obesity and T2D.


Asunto(s)
Agonistas de los Receptores de Amilina , Diabetes Mellitus Tipo 2 , Animales , Ratas , Agonistas de los Receptores de Amilina/farmacología , Agonistas de los Receptores de Amilina/uso terapéutico , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Polipéptido Amiloide de los Islotes Pancreáticos/farmacología , Polipéptido Amiloide de los Islotes Pancreáticos/uso terapéutico , Obesidad/tratamiento farmacológico , Ratas Sprague-Dawley , Receptores de Calcitonina/agonistas , Receptores de Calcitonina/uso terapéutico , Pérdida de Peso
4.
Clin Biochem ; 97: 11-24, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34453894

RESUMEN

OBJECTIVES: There is a need for precision medicine and an unspoken promise of an optimal approach for identification of the right patients for value-based medicine based on big data. However, there may be a misconception that measurement of proteins is more valuable than measurement of fewer selected biomarkers. In population-based research, variation may be somewhat eliminated by quantity. However, this fascination of numbers may limit the attention to and understanding of the single. This review highlights that protein measurements (with collagens as examples) may mean different things depending on the targeted epitope - formation or degradation of tissues, and even signaling potential of proteins. DESIGN AND METHODS: PubMed was searched for collagen, neo-epitope, biomarkers. RESULTS: Ample examples of assays with specific epitopes, either pathological such as HbA1c, or domain specific such as pro-peptides, which total protein arrays would not have identified were evident. CONCLUSIONS: We suggest that big data may be considered as the funnel of data points, in which most important parameters will be selected. If the technical precision is low or the biological accuracy is limited, and we include suboptimal quality of biomarkers, disguised as big data, we may not be able to fulfill the promise of helping patients searching for the optimal treatment. Alternatively, if the technical precision of the total protein quantification is high, but we miss the functional domains with the most considerable biological meaning, we miss the most important and valuable information of a given protein. This review highlights that measurements of the same protein in different ways may provide completely different meanings. We need to understand the pathological importance of each epitope quantified to maximize protein measurements.


Asunto(s)
Enfermedades Cardiovasculares/metabolismo , Colágeno/inmunología , Epítopos , Proteínas/análisis , Proteínas/metabolismo , Membrana Basal/metabolismo , Remodelación Ósea/inmunología , Colágeno/análisis , Colágeno/metabolismo , Enfermedades Gastrointestinales/metabolismo , Humanos , Riñón/metabolismo , Cirrosis Hepática/metabolismo , Neoplasias/inmunología , Pronóstico , Dominios Proteicos , Procesamiento Proteico-Postraduccional , Proteínas/inmunología
5.
Alzheimers Res Ther ; 13(1): 142, 2021 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-34425883

RESUMEN

BACKGROUND: Varoglutamstat (formerly PQ912) is a small molecule that inhibits the activity of the glutaminyl cyclase to reduce the level of pyroglutamate-A-beta (pGluAB42). Recent studies confirm that pGluAB42 is a particular amyloid form that is highly synaptotoxic and plays a significant role in the development of AD. METHODS: This paper describes the design and methodology behind the phase 2b VIVIAD-trial in AD. The aim of this study is to evaluate varoglutamstat in a state-of-the-art designed, placebo-controlled, double-blind, randomized clinical trial for safety and tolerability, efficacy on cognition, and effects on brain activity and AD biomarkers. In addition to its main purpose, the trial will explore potential associations between novel and established biomarkers and their individual and composite relation to disease characteristics. RESULTS: To be expected early 2023 CONCLUSION: This state of the art phase 2b study will yield important results for the field with respect to trial methodology and for the treatment of AD with a small molecule directed against pyroglutamate-A-beta. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04498650.


Asunto(s)
Enfermedad de Alzheimer , Aminoaciltransferasas , Método Doble Ciego , Humanos , Resultado del Tratamiento
6.
Mol Metab ; 53: 101282, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34214708

RESUMEN

OBJECTIVE: Dual amylin and calcitonin receptor agonists (DACRAs) are novel therapeutic agents that not only improve insulin sensitivity but also work as an adjunct to established T2DM therapies. DACRAs are currently administered once daily, though it is unknown whether DACRAs with increased plasma half-life can be developed as a once-weekly therapy. METHODS: The in vitro potencies of the KBP-066A and KBP-066 (non-acylated) were assessed using reporter assays. Acylation functionality was investigated by a combination of pharmacokinetics and acute food intake in rats. in vivo efficacies were investigated head-to-head in obese (HFD) and T2D (ZDF) models. RESULTS: In in vitro, KBP-066A activated the CTR and AMY-R potently, with no off-target activity. Acylation functionality was confirmed by acute tests, as KBP-066A demonstrated a prolonged PK and PD response compared to KBP-066. Both compounds induced potent and dose-dependent weight loss in the HFD rat model. In ZDF rats, fasting blood glucose/fasting insulin levels (tAUC) were reduced by 39%/50% and 36%/47% for KBP-066 and KBP-066A, respectively. This effect resulted in a 31% and 46% vehicle-corrected reduction in HbA1c at the end of the study for KBP-066 and KBP-066A, respectively. CONCLUSIONS: Here, we present pre-clinical data on an acylated DACRA, KBP-066A. The in vivo efficacy of KBP-066A is significantly improved compared to its non-acylated variant regarding weight loss and glycemic control in obese (HFD) and obese diabetic rats (ZDF). This compendium of pre-clinical studies highlights KBP-066A as a promising, once-weekly therapeutic agent for treating T2DM and obesity.


Asunto(s)
Agonistas de los Receptores de Amilina/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Obesidad/tratamiento farmacológico , Receptores de Calcitonina/agonistas , Receptores de Polipéptido Amiloide de Islotes Pancreáticos/metabolismo , Agonistas de los Receptores de Amilina/química , Animales , Línea Celular , Dieta Alta en Grasa/efectos adversos , Control Glucémico , Humanos , Masculino , Ratas , Ratas Sprague-Dawley , Pérdida de Peso/efectos de los fármacos
7.
Osteoarthritis Cartilage ; 27(9): 1339-1346, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31176015

RESUMEN

OBJECTIVES: Pain and disability are the main clinical manifestations of osteoarthritis, for which only symptomatic therapies are available. Hence, there is a need for therapies that can simultaneously alter disease progression and provide pain relief. KBP is a dual amylin- and calcitonin-receptor agonist with antiresorptive and chondroprotective properties. In this study we investigated the effect of KBP in a rat model of osteoarthritis. METHODS: Medial meniscectomy (MNX) was performed in 39 rats, while 10 underwent sham surgery. Rats were treated with KBP and/or naproxen. Nociception was assessed by mechanical and cold allodynia, weight bearing asymmetry, and burrowing behavior. Blood samples were collected for biomarker measurements, and knees for histology. Cartilage histopathology was evaluated according to the advanced Osteoarthritis Research International (OARSI) score and KBPs in vitro antiresorptive effects were assessed using human osteoclasts cultured on bone. RESULTS: The MNX animals displayed an increased nociceptive behavior. Treatment with KBP attenuated the MNX-induced osteoarthritis-associated joint pain. The cartilage histopathology was significantly lower in rats treated with KBP than in MNX animals. Bone and cartilage degradation, assessed by CTX-I and CTX-II plasma levels, were decreased in all KBP-treated groups and KBP potently inhibited bone resorption in vitro. CONCLUSIONS: Our study demonstrates the effectiveness of KBP in ameliorating osteoarthritis-associated joint pain and in protecting the articular cartilage, suggesting KBP as a potential drug candidate for osteoarthritis.


Asunto(s)
Agonistas de los Receptores de Amilina/uso terapéutico , Cartílago Articular/patología , Osteoartritis/tratamiento farmacológico , Dolor/prevención & control , Animales , Calcitonina/análogos & derivados , Cartílago Articular/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Osteoartritis/complicaciones , Osteoartritis/patología , Ratas , Ratas Endogámicas Lew , Receptores de Calcitonina/agonistas
8.
J Prev Alzheimers Dis ; 4(3): 194-200, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29182710

RESUMEN

BACKGROUND: Identification of subjects with a progressive disease phenotype is an urgent need in the pharmaceutical industry where most of the recent clinical trials in Alzheimer's disease have failed. OBJECTIVES: The objective of this study was to identify subgroups of individuals with objective cognitive impairment (OCI), who were most likely to progress to dementia and to identify the risk factors associated with progression. DESIGN: Prospective cohort study. SETTING: Population-based. PARTICIPANTS: 5,380 elderly women from Denmark. MEASUREMENTS: The Short Blessed Test and a category fluency test with animal naming, was used to assess cognitive function, and to classify them into different groups of OCI. RESULTS: OCI was identified in 852 subjects at baseline. The risk of dementia was elevated for OCI subjects as compared to subjects with normal cognition (HR 1.46[1.19-1.79]). The courses of OCI were studied in a sub-cohort who completed the cognitive assessment at both the baseline and the follow-up visit (n = 1,933). Of these subjects 203 had OCI at baseline. The multi-domain subtypes of OCI were associated with progressive OCI. Subjects most likely to progress were older, physically inactive, had a higher level of total cholesterol (>6.5 mmol/L) and had a history of depression as compared to subjects with a non-progressive course of OCI. CONCLUSIONS: In this cohort we identified a risk profile associated with progression from OCI in older women. The degree of impairment at baseline was an important predictor of conversion to dementia, additionally several modifiable risk factors were associated with progression.


Asunto(s)
Disfunción Cognitiva/epidemiología , Demencia/epidemiología , Factores de Edad , Colesterol/sangre , Disfunción Cognitiva/fisiopatología , Demencia/fisiopatología , Dinamarca , Depresión/epidemiología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Pruebas Neuropsicológicas , Estudios Prospectivos , Factores de Riesgo , Conducta Sedentaria
9.
J Neuromuscul Dis ; 3(3): 333-346, 2016 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-27854226

RESUMEN

For several decades, serological biomarkers of neuromuscular diseases as dystrophies, myopathies and myositis have been limited to routine clinical biochemistry panels. Gauging the pathological progression is a prerequisite for proper treatment and therefore identifying accessible, easy to monitor biomarkers that can predict the disease progression would be an important advancement. Most muscle diseases involve accelerated muscle fiber degradation, inflammation, fatty tissue substitution and/or fibrosis. All these pathological traits have been shown to give rise to serological peptide biomarkers in other tissues, underlining the potential application of existing biomarkers of such traits in muscle disorders. A significant quantity of tissue is involved in these pathological mechanisms alongside with qualitative changes in protein turnover in myofibrillar, extra-cellular matrix and immunological cell protein fractions accompanied by alterations in body fluids. We propose that protein and peptides can leak out of the afflicted muscles and can be of use in diagnosis, prediction of pathology trajectory and treatment efficacy. Proteolytic cleavage systems are especially modulated during a range of muscle pathologies, thereby giving rise to peptides that are differentially released during disease manifestation. Therefore, we believe that pathology-specific post-translational modifications like cleavages can give rise to neoepitope peptides that may represent a promising class of peptides for discovery of biomarkers pertaining to neuromuscular diseases.


Asunto(s)
Dermatomiositis/metabolismo , Epítopos/metabolismo , Distrofias Musculares/metabolismo , Péptidos/metabolismo , Biomarcadores/metabolismo , Progresión de la Enfermedad , Fibrosis , Humanos , Inflamación , Fibras Musculares Esqueléticas/metabolismo , Enfermedades Musculares/metabolismo , Polimiositis/metabolismo , Pronóstico , Procesamiento Proteico-Postraduccional
10.
Climacteric ; 18 Suppl 2: 10-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26507704

RESUMEN

Estrogen and bone health form a cornerstone of osteoporosis management. Diagnosis of osteoporosis is performed using bone mineral density (BMD), despite the limitations associated with this. Within the last 25 years, numerous bone turnover markers (BTM) have been developed, and this has led to a marked improvement in drug development for osteoporosis and understanding of fast bone losers. Estrogen research has provided landmark research on understanding the relationship between osteoporosis and BTMs. Clinical studies have illustrated how measurement of BTMs can assist in prediction of rapid bone loss, future fractures and, most importantly, the fracture efficacy of drugs. The BTMs provide information independent of BMD and fracture history. In addition, changes in bone turnover within 1 month predict later changes in BMD, which allows for early efficacy and prognostic measures. The aim is to provide a careful review of the possibilities that implementation of BTMs into clinical practice have provided, while placed in a historical context. The primary focus is on how the BTMs have revolutionized clinical trials on osteoporosis drugs through their ability to supplement bone mass measurements and fracture efficacy endpoints.


Asunto(s)
Biomarcadores/metabolismo , Remodelación Ósea/fisiología , Osteoporosis Posmenopáusica/metabolismo , Fracturas Osteoporóticas/metabolismo , Biomarcadores/análisis , Densidad Ósea/fisiología , Femenino , Humanos , Osteoporosis Posmenopáusica/diagnóstico , Fracturas Osteoporóticas/diagnóstico , Estándares de Referencia , Medición de Riesgo/métodos
11.
Curr Alzheimer Res ; 12(9): 829-36, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26159200

RESUMEN

Differential diagnosis of AD is still a challenge due to overlapping features with other types of dementia. Biomarkers for the differential diagnosis of AD can improve the diagnostic value of the disease and ensure an appropriate treatment of patients. The aim of this study was to evaluate the potential of two neo-epitope fragments of Tau as serum biomarkers for differential diagnosis of AD. The neo-epitope fragments of Tau were assessed in a cross-sectional cohort of subjects with AD, MCI, other dementias or subjects with non-dementia related memory complaints. The two Tau neo-epitope fragments were an ADAM10-generated fragment (Tau-A) and a caspase-3-generated fragment (Tau-C). The serum levels of the fragments were measured by two competitive ELISAs detecting Tau-A and Tau-C, respectively. Tau-A and Tau-C were able to separate subjects with AD and MCI from those with other dementias (p<0.0042 and p<0.05), and Tau-A could also discriminate between AD and MCI patients and subjects with non-dementia related memory complaints (p<0.05). Tau-A showed a significantly greater discrimination between AD and MCI subjects and patients with other dementias when compared to CSF biomarkers t-Tau and p-Tau. The ability of Tau-A to differentiate between AD and MCI from other dementias was comparable with CSF Aß1-42, t-Tau/Aß1-42 and p-Tau/Aß1-42. The separation between the diagnostic groups was significantly improved when the CSF biomarkers as well as age and BMI were used in combination with Tau-A (AUC=0.87, 95% CI: 0.75-0.94) (p<0.0001). In conclusion, this study shows that a neoepitope fragment of Tau detected in serum can provide guidance on the differential diagnosis of AD.


Asunto(s)
Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Proteínas tau/sangre , Anciano , Envejecimiento/sangre , Envejecimiento/líquido cefalorraquídeo , Enfermedad de Alzheimer/líquido cefalorraquídeo , Péptidos beta-Amiloides/líquido cefalorraquídeo , Área Bajo la Curva , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Índice de Masa Corporal , Disfunción Cognitiva/sangre , Disfunción Cognitiva/diagnóstico , Estudios Transversales , Diagnóstico Diferencial , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/líquido cefalorraquídeo , Curva ROC , Proteínas tau/líquido cefalorraquídeo
12.
Exp Gerontol ; 58: 83-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25077715

RESUMEN

PURPOSE: In this study we sought to determine whether a Titin peptide fragment can serve as a clinical biomarker for changes in muscle mass. METHODS: Mass spectrometry was used to identify Titin fragment in urine. An antibody against this Titin sequence was raised and used to develop a competitive ELISA assay for measurement in serum. Rat tissue extractions in the presence or absence of a series of proteases of interest were used to identify its enzymatic origin. A rat model of dexamethasone (DEX) induced muscle atrophy and a human 56-day bed rest study with and without vibration therapy were used to assess biological and clinical relevance. RESULTS: A technically robust ELISA measuring the Titin fragment was developed against a Titin peptide fragment identified in human urine. The fragment was shown to be produced primarily by MMP-2 cleavage of Titin. In the rat muscle DEX induced atrophy model, Titin-MMP2 fragment was decreased in the beginning of DEX treatment, and then significantly increased later on during DEX administration. In the human bed rest study, the Titin-MMP2 fragment was initially decreased 11.9 (±3.7) % after 1day of bed rest, and then gradually increased ending up at a 16.4 (±4.6) % increase at day 47. CONCLUSIONS: We developed a robust ELISA measuring a muscle derived MMP-2 generated Titin degradation fragment in rat and human serum. Importantly, the fragment can be measured in serum and that these levels are related to induction of skeletal muscle atrophy.


Asunto(s)
Conectina/sangre , Metaloproteinasa 2 de la Matriz/metabolismo , Músculo Esquelético/enzimología , Atrofia Muscular/enzimología , Fragmentos de Péptidos/sangre , Animales , Reposo en Cama/efectos adversos , Biomarcadores/sangre , Dexametasona , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Músculo Esquelético/patología , Atrofia Muscular/sangre , Atrofia Muscular/etiología , Atrofia Muscular/patología , Atrofia Muscular/prevención & control , Valor Predictivo de las Pruebas , Ratas Sprague-Dawley , Factores de Tiempo , Vibración/uso terapéutico
13.
Osteoarthritis Cartilage ; 22(1): 7-16, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24216058

RESUMEN

For both economic and ethical reasons, identification of the optimal treatment for each individual patient is a pressing concern, not only for the patients and their physician, but also health care payers and the pharmaceutical industry. In the field of osteoarthritis (OA) this is of particular relevance, due to the heterogeneity of the disease and the very large number of affected individuals. There is a need to pair the right patients with the right therapeutic modes of action. At present, the clinical trial failures in OA may be a consequence of both bona fide treatment failures and trial failures due to clinical design deficiencies. Tools are needed for characterization and segregation of patients with OA. Key lessons may be learned from advances with another form of arthritis, namely rheumatoid arthritis (RA). Personalized health care (PHC) may be more advantageous for a number of specific indications which are characterized by costly therapy, low response rates and significant problems associated with trial and error prescription, including the risk of serious side effects. We discuss the use of diagnostic practices guiding RA treatment, which may serve as a source of key insights for diagnostic practices in OA. We discuss the emerging concept of PHC, and outline the opportunities and current successes and failures across the RA field, as the OA field collects further data to support the hypothesis. We attempt to outline a possible path forward to assist patients, physicians, payers and the pharmaceutical industry in assuring the 'right' patients are treated with the 'right drug' in OA. Finally we highlight methods for possible segregation of OA patients that would allow identification of patient subtypes, such as OA driven by inflammation that may be ideally suited for PHC and for targeted therapies.


Asunto(s)
Osteoartritis/terapia , Medicina de Precisión/métodos , Artritis Reumatoide/terapia , Biomarcadores/metabolismo , Tecnología Biomédica/métodos , Tecnología Biomédica/tendencias , Humanos , Osteoartritis/diagnóstico , Osteoartritis/patología , Fenotipo , Medicina de Precisión/tendencias
14.
Ann Rheum Dis ; 73(2): 336-48, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24285494

RESUMEN

Osteoarthritis (OA) is the most common form of arthritic disease, and a major cause of disability and impaired quality of life in the elderly. OA is a complex disease of the entire joint, affecting bone, cartilage and synovium that thereby presents multiple targets for treatment. This manuscript will summarise emerging observations from cell biology, preclinical and preliminary clinical trials that elucidate interactions between the bone and cartilage components in particular. Bone and cartilage health are tightly associated. Ample evidence has been found for bone changes during progression of OA including, but not limited to, increased turnover in the subchondral bone, undermineralisation of the trabecular structure, osteophyte formation, bone marrow lesions and sclerosis of the subchondral plate. Meanwhile, a range of investigations has shown positive effects on cartilage health when bone resorption is suppressed, or deterioration of the cartilage when resorption is increased. Known bone therapies, namely oestrogens, selective oestrogen receptor modifiers (SERMs), bisphosphonates, strontium ranelate, calcitonin and parathyroid hormone, might prove useful for treating two critical tissue components of the OA joint, the bone and the cartilage. An optimal treatment for OA likely targets at least these two tissue components. The patient subgroups for whom these therapies are most appropriate have yet to be fully defined but would likely include, at a minimum, those with high bone turnover.


Asunto(s)
Anabolizantes/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Remodelación Ósea/efectos de los fármacos , Cartílago Articular/metabolismo , Osteoartritis/tratamiento farmacológico , Anabolizantes/farmacología , Conservadores de la Densidad Ósea/farmacología , Remodelación Ósea/fisiología , Cartílago Articular/efectos de los fármacos , Humanos , Osteoartritis/patología , Osteoartritis/fisiopatología , Osteoblastos/metabolismo , Osteoblastos/patología , Osteoclastos/metabolismo , Osteoclastos/patología
15.
Clin Biochem ; 46(15): 1601-6, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23623829

RESUMEN

OBJECTIVE: Cathepsin K plays essential roles in bone resorption and is intensely investigated as a therapeutic target for the treatment of osteoporosis. Hence an assessment of the active form of cathepsin K may provide important biological information in metabolic bone diseases, such as osteoporosis or ankylosing spondylitis. METHODS: Presently there are no robust assays for the assessment of active cathepsin K in serum, and therefore an ELISA specifically detecting the N-terminal of the active form of cathepsin K was developed. RESULTS: The assay was technically robust, with a lowest limit of detection (LOD) of 0.085 ng/mL. The average intra- and inter-assay CV% were 6.60% and 8.56% respectively. The dilution recovery and spike recovery tests in human serum were within 100±20% within the range of the assay. A comparison of latent and active cathepsin K confirmed specificity towards the active form. Quantification of the levels of active cathepsin K in supernatants of purified human osteoclasts compared to corresponding macrophages showed a 30-fold induction (p<0.001). In contrast, in serum samples from osteoporotic women on estrogen or bisphosphonate therapy and from ankylosing spondylitis patients no clinically relevant differences were observed. CONCLUSION: In summary, we have developed a robust and sensitive assay specifically detecting the active form of cathepsin K; however, while it monitors osteoclasts with high specificity in vitro, it appears that circulating levels of active cathepsin K do not reflect bone changes under these circumstances.


Asunto(s)
Catepsina K/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Osteoclastos/enzimología , Osteoporosis/sangre , Espondilitis Anquilosante/sangre , Animales , Anticuerpos Monoclonales/química , Conservadores de la Densidad Ósea/uso terapéutico , Huesos/enzimología , Huesos/patología , Difosfonatos/uso terapéutico , Activación Enzimática , Femenino , Humanos , Macrófagos/citología , Macrófagos/enzimología , Ratones , Persona de Mediana Edad , Osteoclastos/citología , Osteoporosis/tratamiento farmacológico , Osteoporosis/enzimología , Osteoporosis/patología , Sensibilidad y Especificidad , Espondilitis Anquilosante/enzimología , Espondilitis Anquilosante/patología
16.
BJOG ; 120(8): 948-59, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23489333

RESUMEN

OBJECTIVE: To investigate the individual effects of ibuprofen, diclofenac, naproxen, and piroxicam on pregnancy outcome. DESIGN: Cohort study. SETTING: Norwegian population. POPULATION: A total of 90 417 women and singleton child pairs. METHODS: The Norwegian Mother and Child Cohort Study and Medical Birth Registry of Norway data sets were used. MAIN OUTCOME MEASURES: Infant survival, congenital malformations, structural heart defects, neonatal complications, haemorrhage during pregnancy and postpartum, asthma at age of 18 months. RESULTS: One or more of the four nonsteroidal anti-inflammatory drugs (NSAIDs) were used by 6511 pregnant women (7.2%). No effect on rates of infant survival, congenital malformation, or structural heart defects was found. The use of ibuprofen in the second trimester was significantly associated with low birthweight (adjusted OR 1.7, 95% CI 1.3-2.3), and ibuprofen use in the second and third trimesters was significantly associated with asthma in 18-month-old children (adjusted OR 1.5, 95% CI 1.2-1.9; adjusted OR 1.5, 95% CI 1.1-2.1). The use of diclofenac in the second trimester was significantly associated with low birthweight (adjusted OR 3.1, 95% CI 1.1-9.0), whereas diclofenac use in the third trimester was significantly associated with maternal vaginal bleeding (adjusted OR 1.8, 95% CI 1.1-3.0). No associations with other neonatal complications were found. CONCLUSIONS: The lack of associations with congenital malformations is reassuring. The significant association between diclofenac and ibuprofen use late in pregnancy, and maternal bleeding and asthma in the child, respectively, is consistent with their pharmacological effects. The increased risk of low birthweight may partly have been caused by underlying inflammatory conditions, and was reassuringly similar to the expected baseline risk of low birthweight.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Diclofenaco/efectos adversos , Ibuprofeno/efectos adversos , Naproxeno/efectos adversos , Piroxicam/efectos adversos , Complicaciones del Embarazo/inducido químicamente , Resultado del Embarazo/epidemiología , Adulto , Estudios de Cohortes , Femenino , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Noruega/epidemiología , Embarazo , Estudios Prospectivos , Riesgo , Adulto Joven
17.
Bone ; 53(1): 160-6, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23234813

RESUMEN

CONTEXT: Treatment of osteoporosis with subcutaneous (SC) injections of rhPTH(1-34) or rhPTH(1-84) is associated with significant improvements in BMD and reductions in osteoporotic fractures. However, subcutaneous injections can be associated with discomfort and thus deteriorating compliance. OBJECTIVE: The UGL-OR1001 trial aimed to establish the efficacy and safety parameters of a novel oral tablet formulation of rhPTH(1-31)NH(2) and matching placebo tablets and open-label teriparatide positive control in postmenopausal women with osteoporosis. DESIGN: 24 weeks of randomized, double-blind treatment with once daily doses of 5mg oral treatment or corresponding placebo, or open-label subcutaneous teriparatide. PATIENTS OR OTHER PARTICIPANTS: Women diagnosed with postmenopausal osteoporosis as detected by lumbar spine DXA, with an exclusion of those with prior treatment with bone active agents. INTERVENTION(S): Orally formulated recombinant human PTH(1-31)NH(2) and placebo, or open-label subcutaneous teriparatide as a positive control. MAIN OUTCOME MEASURE(S): The primary endpoint was to characterize the percent change from baseline in bone mineral density (BMD) at L1-L4 axial lumbar spine after 24 weeks in the rhPTH(1-31)NH(2) arm. Secondary and exploratory endpoints included safety and tolerability of the oral formulation, measurement of biochemical markers of bone turnover, and evaluation of the PK profile at first and last dose. The study was registered at ClinicalTrials.gov with the identifier: NCT01321723. RESULTS: The oral tablet formulation of rhPTH(1-31)NH(2) resulted in similar PK profiles at both timepoints with mean C(max) values similar to subcutaneous administration. In the rhPTH(1-31)NH(2) arm, a 2.2% increase in lumbar spine BMD was observed compared to baseline (p<0.001), while no change was observed in the placebo arm. Open-label teriparatide resulted in a 5.1% increase in LS BMD (p<0.001). In the oral PTH study arm, the bone formation marker osteocalcin was increased by 32%, 21% and 23% at Weeks 4, 12 and 24, respectively. There was no significant increase in the level of the bone resorption marker CTx-1. CONCLUSIONS: In summary, these data demonstrate that enteric-coated oral tablet formulation technology consistently generated robust levels of exposure of rhPTH(1-31)NH(2) leading to induction of bone formation without inducing bone resorption resulting in significantly increased levels of LS BMD. Few adverse events were observed, recommending this orally delivered drug candidate for further development.


Asunto(s)
Osteoporosis Posmenopáusica/tratamiento farmacológico , Hormona Paratiroidea/uso terapéutico , Fragmentos de Péptidos/uso terapéutico , Administración Oral , Anciano , Anciano de 80 o más Años , Densidad Ósea , Método Doble Ciego , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/fisiopatología , Hormona Paratiroidea/efectos adversos , Hormona Paratiroidea/farmacocinética , Fragmentos de Péptidos/efectos adversos , Fragmentos de Péptidos/farmacocinética , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapéutico
18.
Menopause Int ; 18(4): 139-46, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23024184

RESUMEN

The female predominance of polyarticular osteoarthritis (OA), and in particular the marked increase of OA in women after the menopause points to a likely involvement of female sex hormones in the maintenance of cartilage homeostasis. This perception has inspired many research groups to investigate the role of estrogens in the modulation of cartilage homeostasis with the ultimate aim to clarify whether estrogen replacement therapy (ERT) could provide benefits in preventing the rapid rise in the prevalence of OA in postmenopausal women. The effects of ERT and selective estrogen-receptor modulators on the joint in various experimental models have been investigated. Clinically, the effects of estrogens have been evaluated by post hoc analysis in clinical trials using biochemical markers of cartilage and bone degradation. Lastly, the Women's Health Initiative trial (WHI) investigated the effects of estrogens on the joint and joint replacements. Even though the exact mode of action still needs to be elucidated, the effect involves both direct and indirect mechanisms on the whole joint pathophysiology. Several animal models have demonstrated structural benefits of estrogens, as well as significant effects on joint inflammation. This is in complete alignment with clinical data using biochemical markers of joint degradation which demonstrated approximately 50% inhibition of cartilage destruction. These finding were recently validated in WHI, where women taking estrogens had significantly less joint replacement. In conclusion, the pleiotropic effect of estrogens on several different tissues may match the complicated aetiology of OA in some important aspects.


Asunto(s)
Huesos/fisiopatología , Cartílago/fisiopatología , Estrógenos/uso terapéutico , Menopausia/fisiología , Osteoartritis/fisiopatología , Conservadores de la Densidad Ósea/farmacología , Conservadores de la Densidad Ósea/uso terapéutico , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/fisiopatología , Cartílago/efectos de los fármacos , Condrocitos/efectos de los fármacos , Terapia de Reemplazo de Estrógeno , Estrógenos/farmacología , Femenino , Homeostasis , Humanos , Osteoartritis/tratamiento farmacológico , Osteoblastos/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Sinovitis/fisiopatología
19.
Int J Alzheimers Dis ; 2012: 209409, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22779024

RESUMEN

Drug development for dementias is significantly hampered by the lack of easily accessible biomarkers. Fluid biomarkers of dementias provide indications of disease stage, but have little prognostic value, cannot detect early pathological changes, and can only be measured in CSF (cerebrospinal fluid) which significantly limits their applicability. In contrast, imaging based biomarkers can provide indications of probability of disease progression, yet are limited in applicability due to cost, radiation and radio-tracers. These aspects highlight the need for other approaches to the development of biomarkers of dementia, which should focus on not only providing information about pathological changes, but also on being measured easily and reproducibly. For other diseases, focus on development of assays monitoring highly specific protease-generated cleavage fragments of proteins has provided assays, which in serum or plasma have the ability to predict early pathological changes. Proteolytic processing of brain proteins, such as tau, APP, and α-synuclein, is a key pathological event in dementias. Here, we speculate that aiming biomarker development for dementias at detecting small brain protein degradation fragments of generated by brain-derived proteases specifically in blood samples could lead to the development of novel markers of disease progression, stage and importantly of treatment efficacy.

20.
Br J Pharmacol ; 167(1): 151-63, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22506938

RESUMEN

BACKGROUND AND PURPOSE: Oral salmon calcitonin (sCT), a dual-action amylin and calcitonin receptor agonist, improved glucose homeostasis in diet-induced obese rats. Here, we have evaluated the anti-diabetic efficacy of oral sCT using parameters of glycaemic control and beta-cell morphology in male Zucker diabetic fatty (ZDF) rats, a model of type 2 diabetes. EXPERIMENTAL APPROACH: Male ZDF rats were treated with oral sCT (0.5, 1.0 or 2 mg·kg(-1) ) or oral vehicle twice daily from age 8 to 18 weeks. Zucker lean rats served as control group. Fasting and non-fasted blood glucose, glycosylated haemoglobin (HbA1c) and levels of pancreas and incretin hormones were determined. Oral glucose tolerance test and i.p. glucose tolerance test were compared, and beta-cell area and function were evaluated. KEY RESULTS: Oral sCT treatment dose-dependently attenuated fasting and non-fasted hyperglycaemia during the intervention period. At the end of the study period, oral sCT treatment by dose decreased diabetic hyperglycaemia by ∼9 mM and reduced HbA1c levels by 1.7%. Furthermore, a pronounced reduction in glucose excursions was dose-dependently observed for oral sCT treatment during oral glucose tolerance test. In addition, oral sCT treatment sustained hyperinsulinaemia and attenuated hyperglucagonaemia and hypersecretion of total glucagon-like peptide-1 predominantly in the basal state. Lastly, oral sCT treatment dose-dependently improved pancreatic beta-cell function and beta-cell area at study end. CONCLUSIONS AND IMPLICATIONS: Oral sCT attenuated diabetic hyperglycaemia in male ZDF rats by improving postprandial glycaemic control, exerting an insulinotropic and glucagonostatic action in the basal state and by preserving pancreatic beta-cell function and beta-cell area.


Asunto(s)
Calcitonina/administración & dosificación , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hiperglucemia/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Células Secretoras de Insulina/efectos de los fármacos , Administración Oral , Animales , Glucemia/análisis , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Polipéptido Inhibidor Gástrico/sangre , Péptido 1 Similar al Glucagón/sangre , Prueba de Tolerancia a la Glucosa , Hemoglobina Glucada/análisis , Hiperglucemia/metabolismo , Hiperglucemia/patología , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Masculino , Ratas , Ratas Zucker
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