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1.
PLoS Biol ; 19(1): e3001062, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33395408

RESUMO

Lyme carditis is an extracutaneous manifestation of Lyme disease characterized by episodes of atrioventricular block of varying degrees and additional, less reported cardiomyopathies. The molecular changes associated with the response to Borrelia burgdorferi over the course of infection are poorly understood. Here, we identify broad transcriptomic and proteomic changes in the heart during infection that reveal a profound down-regulation of mitochondrial components. We also describe the long-term functional modulation of macrophages exposed to live bacteria, characterized by an augmented glycolytic output, increased spirochetal binding and internalization, and reduced inflammatory responses. In vitro, glycolysis inhibition reduces the production of tumor necrosis factor (TNF) by memory macrophages, whereas in vivo, it produces the reversion of the memory phenotype, the recovery of tissue mitochondrial components, and decreased inflammation and spirochetal burdens. These results show that B. burgdorferi induces long-term, memory-like responses in macrophages with tissue-wide consequences that are amenable to be manipulated in vivo.


Assuntos
Borrelia burgdorferi/imunologia , Cardiomiopatias/etiologia , Memória Imunológica , Doença de Lyme/imunologia , Macrófagos/fisiologia , Animais , Cardiomiopatias/imunologia , Cardiomiopatias/microbiologia , Cardiomiopatias/patologia , Células Cultivadas , Endocardite Bacteriana/complicações , Endocardite Bacteriana/imunologia , Endocardite Bacteriana/microbiologia , Endocardite Bacteriana/patologia , Feminino , Células HEK293 , Coração/microbiologia , Humanos , Doença de Lyme/patologia , Ativação de Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/imunologia , Miócitos Cardíacos/microbiologia , Miócitos Cardíacos/patologia , Células RAW 264.7
3.
J Dairy Sci ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38788847

RESUMO

Ruminant milk composition can be impacted by many factors, primarily inter-species differences, but also environmental factors (e.g., season, feeding system and feed composition). Pasture-based feeding systems are known to be influenced by seasonal effects on grass composition. Spring pasture is rich in protein and low in fiber compared with late-season pasture, potentially inducing variability in the composition of some milk metabolites across the season. This study aimed to investigate inter-species and seasonal differences in the milk metabolome across the 3 major commercial ruminant milk species from factories in New Zealand: bovine, caprine and ovine milk. Bovine and caprine raw milk samples were collected monthly for a period of 9 mo (August-April, 2016-2017; bovine n = 41, caprine n = 44 samples); while ovine milk samples were collected for a period of 5 mo (August-January, n = 20 samples). Milk samples were subjected to biphasic extraction, and untargeted metabolite profiling was performed using 2 separate liquid chromatography high-resolution mass spectrometry analytical methods (polar metabolites and lipids). Major differences in milk metabolome were observed between the 3-ruminant species, with 414 of 587 (71%) polar metabolite features and 210 of 233 (87%) lipid features significantly different between species. Significant seasonal trends were observed in the polar metabolite fraction for bovine, caprine and ovine milk (17, 24 and 32 metabolites, respectively), suggesting that the polar metabolite relative intensities of ovine and caprine milk were more susceptible to changes within seasons than bovine milk. There was no significant seasonal difference for the triglycerides (TG) species measured in bovine milk, while 3 and 52 TG species changed in caprine and ovine milk, respectively, across the seasons. Four phosphatidylcholines and 2 phosphatidylethanolamines varied in caprine milk within the season, and 8 diglycerides varied in ovine milk. The inter-species and seasonal metabolite differences reported here provide a knowledge base of components potentially linked to milk physiochemical properties, and potential health benefits of New Zealand pasture-fed dairy ingredients.

4.
NMR Biomed ; : e4952, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37070533

RESUMO

Hippocampus demyelinating lesions in multiple sclerosis (MS) have been frequently observed in ex vivo histopathological studies; however, they are difficult to image and quantify in vivo. Diffusion tensor imaging (DTI) and T2 mapping could potentially detect such regional in vivo changes if acquired with sufficient spatial resolution. The goal here was to evaluate whether there are focal hippocampal abnormalities in 43 MS patients (35 relapsing-remitting, eight secondary progressive) with and without cognitive impairment (CI) versus 43 controls using high-resolution 1 mm isotropic DTI, as well as complementary methods of T2-weighted and T2 mapping at 3 T. Abnormal hippocampus regions were identified voxel-by-voxel by using mean diffusivity (MD)/T2 thresholds and avoiding voxels attributed to cerebrospinal fluid. When compared with controls, averaged left/right whole hippocampus MD was higher in both MS groups, while lower fractional anisotropy (FA) and volume, and higher T2 relaxometry and T2-weighted signal values, were only significant in CI MS. The hippocampal MD and T2 images/maps were not uniformly affected and focal regions of elevated MD/T2 were evident in MS patients. Both CI and not CI MS groups showed greater proportional areas of the hippocampus with elevated MD, whereas only the CI group showed a greater proportional area of elevated T2 relaxation times or T2-weighted signal. Higher T2 relaxometry and T2-weighted signal values of elevated regions correlated with greater disability and whole hippocampus FA negatively correlated with physical fatigue. High-resolution hippocampus DTI and T2 mapping with less partial volume effects showed whole hippocampus abnormalities with regional elevations of MD/T2 in MS, which could be interpreted as potentially from demyelination, neuron loss, and/or inflammation, and which overall were more extensive in the hippocampus of patients with larger total brain lesion volumes and CI.

5.
Nature ; 547(7661): 109-113, 2017 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-28658205

RESUMO

Activation of the PTEN-PI3K-mTORC1 pathway consolidates metabolic programs that sustain cancer cell growth and proliferation. Here we show that mechanistic target of rapamycin complex 1 (mTORC1) regulates polyamine dynamics, a metabolic route that is essential for oncogenicity. By using integrative metabolomics in a mouse model and human biopsies of prostate cancer, we identify alterations in tumours affecting the production of decarboxylated S-adenosylmethionine (dcSAM) and polyamine synthesis. Mechanistically, this metabolic rewiring stems from mTORC1-dependent regulation of S-adenosylmethionine decarboxylase 1 (AMD1) stability. This novel molecular regulation is validated in mouse and human cancer specimens. AMD1 is upregulated in human prostate cancer with activated mTORC1. Conversely, samples from a clinical trial with the mTORC1 inhibitor everolimus exhibit a predominant decrease in AMD1 immunoreactivity that is associated with a decrease in proliferation, in line with the requirement of dcSAM production for oncogenicity. These findings provide fundamental information about the complex regulatory landscape controlled by mTORC1 to integrate and translate growth signals into an oncogenic metabolic program.


Assuntos
Adenosilmetionina Descarboxilase/metabolismo , Complexos Multiproteicos/metabolismo , Poliaminas/metabolismo , Neoplasias da Próstata/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Adenosilmetionina Descarboxilase/imunologia , Animais , Proliferação de Células , Ativação Enzimática , Everolimo/uso terapêutico , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Metabolômica , Camundongos , Complexos Multiproteicos/antagonistas & inibidores , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Estabilidade Proteica , S-Adenosilmetionina/análogos & derivados , S-Adenosilmetionina/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores
6.
J Biol Chem ; 297(5): 101298, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34637789

RESUMO

Influenza A virus (IAV) infection casts a significant burden on society. It has particularly high morbidity and mortality rates in patients suffering from metabolic disorders. The aim of this study was to relate metabolic changes with IAV susceptibility using well-characterized inbred mouse models. We compared the highly susceptible DBA/2J (D2) mouse strain for which IAV infection is lethal with the C57BL/6J (B6) strain, which exhibits a moderate course of disease and survives IAV infection. Previous studies showed that D2 has higher insulin and glucose levels and is predisposed to develop diet-induced type 2 diabetes. Using high-resolution liquid chromatography-coupled MS, the plasma metabolomes of individual animals were repeatedly measured up to 30 days postinfection. The biggest metabolic difference between these strains in healthy and infected states was in the levels of malonylcarnitine, which was consistently increased 5-fold in D2. Other interstrain and intrastrain differences in healthy and infected animals were observed for acylcarnitines, glucose, branched-chain amino acids, and oxidized fatty acids. By mapping metabolic changes to canonical pathways, we found that mitochondrial beta-oxidation is likely disturbed in D2 animals. In noninfected D2 mice, this leads to increased glycerolipid production and reduced acylcarnitine production, whereas in infected D2 animals, peroxisomal beta-oxidation becomes strongly increased. From these studies, we conclude that metabolic changes caused by a distortion of mitochondrial and peroxisomal metabolism might impact the innate immune response in D2, leading to high viral titers and mortality.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Vírus da Influenza A/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Animais , Carnitina/análogos & derivados , Carnitina/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/virologia , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/virologia , Camundongos , Oxirredução
7.
Eur J Neurosci ; 55(1): 277-294, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34806796

RESUMO

Diffusion tensor imaging (DTI) and volumetric magnetic resonance imaging (MRI) have shown white matter (WM) and deep grey matter (GM) abnormalities in the limbic system of multiple sclerosis (MS) participants. Structures like the fornix have been associated with cognitive impairment (CI) in MS, but the diffusion metrics are often biased by partial volume effects from cerebrospinal fluid (CSF) due to its small bundle size and intraventricular location. These errors in DTI parameter estimation worsen with atrophy in MS. The goal here was to evaluate DTI parameters and volumes of the fornix, as well as associated deep GM structures like the thalamus and hippocampus, with high-resolution fluid-attenuated inversion recovery (FLAIR)-DTI at 3T in 43 MS patients, with and without CI, versus 43 controls. The fornix, thalamus and hippocampus displayed atrophy and/or abnormal diffusion metrics, with the fornix showing the most extensive changes within the structures studied here, mainly in CI MS. The affected fornix volumes and diffusion metrics were associated with thalamic atrophy and atypical diffusion metrics in interconnected limbic GM, larger total lesion volume and global brain atrophy. Lower fractional anisotropy (FA) and higher mean and radial diffusivity in the fornix, lower hippocampus FA and lower thalamus volume were strongly correlated with CI in MS. Hippocampus FA and thalamus atrophy were negatively correlated with fatigue and longer time since MS symptoms onset, respectively. FLAIR-DTI and volumetric analyses provided methodologically superior evidence for microstructural abnormalities and extensive atrophy of the fornix and interconnected deep GM in MS that were associated with cognitive deficits.


Assuntos
Disfunção Cognitiva , Esclerose Múltipla , Substância Branca , Atrofia/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Imagem de Tensor de Difusão/métodos , Substância Cinzenta , Humanos , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico por imagem , Substância Branca/patologia
8.
Int J Mol Sci ; 22(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34681804

RESUMO

The proteomic profiling of serum samples supposes a challenge due to the large abundance of a few blood proteins in comparison with other circulating proteins coming from different tissues and cells. Although the sensitivity of protein detection has increased enormously in the last years, specific strategies are still required to enrich less abundant proteins and get rid of abundant proteins such as albumin, lipoproteins, and immunoglobulins. One of the alternatives that has become more promising is to characterize circulating extracellular vesicles from serum samples that have great interest in biomedicine. In the present work, we enriched the extracellular vesicles fraction from human serum by applying different techniques, including ultracentrifugation, size-exclusion chromatography, and two commercial precipitation methods based on different mechanisms of action. To improve the performance and efficacy of the techniques to promote purity of the preparations, we have employed a small volume of serum samples (<100 mL). The comparative proteomic profiling of the enriched preparations shows that ultracentrifugation procedure yielded a larger and completely different set of proteins than other techniques, including mitochondrial and ribosome related proteins. The results showed that size exclusion chromatography carries over lipoprotein associated proteins, while a polymer-based precipitation kit has more affinity for proteins associated with granules of platelets. The precipitation kit that targets glycosylation molecules enriches differentially protein harboring glycosylation sites, including immunoglobulins and proteins of the membrane attack complex.


Assuntos
Proteínas Sanguíneas/análise , Vesículas Extracelulares/química , Proteômica/métodos , Proteínas Sanguíneas/metabolismo , Cromatografia em Gel , Vesículas Extracelulares/metabolismo , Glicosilação , Humanos , Imunoprecipitação/métodos , Lipoproteínas/análise , Lipoproteínas/sangue , Lipoproteínas/metabolismo , Proteoma/análise , Proteoma/metabolismo , Proteínas Ribossômicas/análise , Proteínas Ribossômicas/sangue , Proteínas Ribossômicas/metabolismo , Ultracentrifugação/métodos
9.
BMC Musculoskelet Disord ; 21(1): 501, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727440

RESUMO

An amendment to this paper has been published and can be accessed via the original article.

10.
BMC Musculoskelet Disord ; 21(1): 349, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503480

RESUMO

BACKGROUND: Understanding the metabolic and lipidomic changes that accompany bone loss in osteoporosis might provide insights about the mechanisms behind molecular changes and facilitate developing new drugs or nutritional strategies for osteoporosis prevention. This study aimed to examine the effects of short- or long-term glucocorticoid-induced osteoporosis on plasma metabolites and lipids of ovariectomized (OVX) sheep. METHODS: Twenty-eight aged ewes were divided randomly into four groups: an OVX group, OVX in combination with glucocorticoids for two months (OVXG2), and OVX in combination with five doses of glucocorticoids (OVXG5) to induce bone loss, and a control group. Liquid chromatography-mass spectrometry untargeted metabolomic analysis was applied to monthly plasma samples to follow the progression of osteoporosis over five months. RESULTS: The metabolite profiles revealed significant differences in the plasma metabolome of OVX sheep and OVXG when compared with the control group by univariate analysis. Nine metabolites were altered, namely 5-methoxytryptophan, valine, methionine, tryptophan, glutaric acid, 2-pyrrolidone-5-carboxylic acid, indole-3-carboxaldehyde, 5-hydroxylysine and malic acid. Similarly, fifteen lipids were perturbed from multiple lipid classes such as lysophoslipids, phospholipids and ceramides. CONCLUSION: This study showed that OVX and glucocorticoid interventions altered the metabolite and lipid profiles of sheep, suggesting that amino acid and lipid metabolisms are potentially the main perturbed metabolic pathways regulating bone loss in OVX sheep.


Assuntos
Densidade Óssea/efeitos dos fármacos , Glucocorticoides/efeitos adversos , Lipídeos/sangue , Metaboloma , Osteoporose/sangue , Osteoporose/induzido quimicamente , Animais , Cromatografia Líquida , Modelos Animais de Doenças , Feminino , Lipidômica , Espectrometria de Massas , Ovariectomia , Ovinos
11.
J Nutr ; 148(11): 1743-1750, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30383281

RESUMO

Background: Actinidin, a cysteine protease in kiwifruit (KF), increases both the gastric digestion and gastric-emptying rate of beef muscle protein. Objective: This study aimed to determine the relation between the rate of digested nitrogen entering the small intestine (SI; a function of the extent of gastric digestion and gastric-emptying rate) and the disappearance of amino acids (AAs) in different parts of the SI at set times postfeeding. Methods: Male 9-wk-old pigs (n = 90; mean ± SD body weight: 28 ± 2.9 kg) were fed a diet containing 14% beef for 3 d. The beef-based diet was supplemented with green KF pulp (containing actinidin), gold KF pulp supplemented with actinidin, or gold KF pulp alone (no actinidin). The KF or actinidin amounts corresponded to the intake of 2 KFs/human meal. On day 3, pigs were killed at 0.5, 1, 3, 5, and 7 h postprandially. Stomach chyme was analyzed to determine the rate of digested nitrogen entering the SI. Apparent AA digestibility at set times was determined in the proximal, medial, and distal SI. Polynomial and correlation analyses were conducted. Results: The rate of digested nitrogen entering the SI was higher (P < 0.001) with actinidin (e.g., >44% at 5 h postprandially). Actinidin also increased the apparent AA digestibility at the proximal and medial SI (P ≤ 0.05) at set times (e.g., 42% and 15% greater for arginine, respectively), but not in general for the distal SI (P > 0.05). At the proximal SI, apparent AA digestibility was correlated more strongly with the digested nitrogen entering the SI (r = 0.73, P < 0.001; n = 57) than with gastric emptying (r = 0.64, P < 0.001) or gastric protein digestion (r = 0.57, P < 0.001). Similar trends were observed for the medial SI. Conclusion: The rate of digested nitrogen entering the SI is an accurate predictor of the rate of AA digestibility and the location of AA absorption in the pig SI.


Assuntos
Aminoácidos/metabolismo , Proteínas Alimentares/metabolismo , Intestino Delgado/fisiologia , Suínos/fisiologia , Actinidia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos , Dieta , Suplementos Nutricionais , Digestão/fisiologia , Motilidade Gastrointestinal , Masculino , Carne/análise , Distribuição Aleatória
12.
Microbiol Spectr ; 11(4): e0506322, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37347184

RESUMO

Several studies have described the contribution of glutamate-transforming microbiota to the development of chronic ailments. For instance, the blood concentration of glutamate is higher in some patients with fibromyalgia, chronic fatigue, and pain. Taking advantage of a naturally occurring strain of Bifidobacterium that is able to transform glutamate in γ-aminobutyric caid (GABA), B. adolescentis IPLA60004, we designed a placebo-controlled intervention to test if the presence of this GABA-producing bifidobacteria in mice was able to impact the concentration of glutamate in the blood in comparison with the administration of other strain of the same species lacking the genes of the glutamate decarboxylase (gad) cluster. Animals were fed every day with 8 log CFU of bacteria in a sterilized milk vehicle for 14 days. Samples from feces and blood were collected during this period, and afterwards animals were sacrificed, tissues were taken from different organs, and the levels of different metabolites were analyzed by ultrahigh-performance liquid chromatography coupled to mass spectrometry. The results showed that both bacterial strains orally administered survived in the fecal content, and animals fed B. adolescentis IPLA60004 showed a significant reduction of their glutamate serum concentration, while a nonsignificant decrease was observed for animals fed a reference strain, B. adolescentis LGM10502. The variations observed in GABA were influenced by the gender of the animals, and no significant changes were observed in different tissues of the brain. These results suggest that orally administered GABA-producing probiotics could reduce the glutamate concentration in blood, opening a case for a clinical trial study in chronic disease patients. IMPORTANCE This work presents the results of a trial using mice as a model that were fed with a bacterial strain of the species B. adolescentis, which possesses different active genes capable of degrading glutamate and converting it into GABA. Indeed, the bacterium is able to survive the passage through the gastric tract and, more importantly, the animals reduce over time the concentration of glutamate in their blood. The importance of this result lies in the fact that several chronic ailments, such as fibromyalgia, are characterized by an increase in glutamate. Our results indicate that an oral diet with this probiotic-type bacteria could reduce the concentration of glutamate and, therefore, reduce the symptoms associated with the excess of this neurotransmitter.


Assuntos
Bifidobacterium adolescentis , Fibromialgia , Probióticos , Camundongos , Animais , Bifidobacterium adolescentis/metabolismo , Ácido Glutâmico/análise , Ácido Glutâmico/metabolismo , Bifidobacterium/genética , Bifidobacterium/metabolismo , Fezes/microbiologia , Ácido gama-Aminobutírico/análise , Ácido gama-Aminobutírico/metabolismo
13.
Cell Metab ; 35(8): 1373-1389.e8, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37527658

RESUMO

There has been an intense focus to uncover the molecular mechanisms by which fasting triggers the adaptive cellular responses in the major organs of the body. Here, we show that in mice, hepatic S-adenosylmethionine (SAMe)-the principal methyl donor-acts as a metabolic sensor of nutrition to fine-tune the catabolic-fasting response by modulating phosphatidylethanolamine N-methyltransferase (PEMT) activity, endoplasmic reticulum-mitochondria contacts, ß-oxidation, and ATP production in the liver, together with FGF21-mediated lipolysis and thermogenesis in adipose tissues. Notably, we show that glucagon induces the expression of the hepatic SAMe-synthesizing enzyme methionine adenosyltransferase α1 (MAT1A), which translocates to mitochondria-associated membranes. This leads to the production of this metabolite at these sites, which acts as a brake to prevent excessive ß-oxidation and mitochondrial ATP synthesis and thereby endoplasmic reticulum stress and liver injury. This work provides important insights into the previously undescribed function of SAMe as a new arm of the metabolic adaptation to fasting.


Assuntos
Neoplasias Hepáticas , S-Adenosilmetionina , Camundongos , Animais , S-Adenosilmetionina/metabolismo , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Jejum , Trifosfato de Adenosina/metabolismo , Metionina Adenosiltransferase/metabolismo , Fosfatidiletanolamina N-Metiltransferase/metabolismo
14.
Metabolites ; 12(8)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-36005586

RESUMO

Steroid hormones play a vital role in the regulation of cellular processes, and dysregulation of these metabolites can provoke or aggravate pathological issues, such as autoimmune diseases and cancer. Regulation of steroid hormones involves different organs and biological compartments. Therefore, it is important to accurately determine their levels in tissues and biofluids to monitor changes after challenge or during disease. In this work, we have developed and optimized the extraction and quantification of 11 key members of the different steroid classes, including androgens, estrogens, progestogens and corticoids. The assay consists of a liquid/liquid extraction step and subsequent quantification by high-resolution liquid chromatography coupled time-of-flight mass spectrometry. The recoveries range between 74.2 to 126.9% and 54.9 to 110.7%, using a cell culture or urine as matrix, respectively. In general, the signal intensity loss due to matrix effect is no more than 30%. The method has been tested in relevant steroidogenic tissues in rat models and it has also been tested in human urine samples. Overall, this assay measures 11 analytes simultaneously in 6 min runtime and it has been applied in adrenal gland, testis, prostate, brain and serum from rats, and urine and extracellular vesicles from humans.

15.
Neuroimage Clin ; 34: 103002, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35413649

RESUMO

PURPOSE: Cerebral amyloid angiopathy (CAA) is a common neuropathological finding and clinical entity that occurs independently and with co-existent Alzheimer's disease (AD) and small vessel disease. We compared diffusion tensor imaging (DTI) metrics of the fornix, the primary efferent tract of the hippocampus between CAA, AD and Mild Cognitive Impairment (MCI) and healthy controls. METHODS: Sixty-eight healthy controls, 32 CAA, 21 AD, and 26 MCI patients were recruited at two centers. Diffusion tensor images were acquired at 3 T with high spatial resolution and fluid-attenuated inversion recovery (FLAIR) to suppress cerebrospinal fluid (CSF) and minimize partial volume effects on the fornix. The fornix was delineated with deterministic tractography to yield mean diffusivity (MD), axial diffusivity (AXD), radial diffusivity (RD), fractional anisotropy (FA) and tract volume. Volumetric measurements of the hippocampus, thalamus, and lateral ventricles were obtained using T1-weighted MRI. RESULTS: Diffusivity (MD, AXD, and RD) of the fornix was highest in AD followed by CAA compared to controls; the MCI group was not significantly different from controls. FA was similar between groups. Fornix tract volume was âˆ¼ 30% lower for all three patient groups compared to controls, but not significantly different between the patient groups. Thalamic and hippocampal volumes were preserved in CAA, but lower in AD and MCI compared to controls. Lateral ventricular volumes were increased in CAA, AD and MCI. Global cognition, memory, and executive function all correlated negatively with fornix diffusivity across the combined clinical group. CONCLUSION: There were significant diffusion changes of the fornix in CAA, AD and MCI compared to controls, despite relatively intact thalamic and hippocampal volumes in CAA, suggesting the mechanisms for fornix diffusion abnormalities may differ in CAA compared to AD and MCI.


Assuntos
Doença de Alzheimer , Angiopatia Amiloide Cerebral , Disfunção Cognitiva , Doença de Alzheimer/patologia , Anisotropia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Fórnice/diagnóstico por imagem , Fórnice/patologia , Humanos
16.
Front Neurol ; 12: 693447, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335450

RESUMO

Introduction: The source of Tissue Sodium Concentration (TSC) increase in Multiple Sclerosis (MS) remains unclear, and could be attributed to altered intracellular sodium concentration or tissue microstructure. This paper investigates sodium in MS using three new MRI sequences. Methods: Three sodium scans were acquired at 4.7 T from 30 patients (11 relapsing-remitting, 10 secondary-progressive, 9 primary-progressive) and 9 healthy controls including: Density-Weighted (NaDW), with very short 30° excitation for more accurate TSC measurement; Projection Acquisition with Coherent MAgNetization (NaPACMAN), designed for enhanced relaxation-based contrast; and Soft Inversion Recovery FLuid Attenuation (NaSIRFLA), developed to reduce fluid space contribution. Signal was measured in both lesions (n = 397) and normal appearing white matter (NAWM) relative to controls in the splenium of corpus callosum and the anterior and posterior limbs of internal capsule. Correlations with clinical and cognitive evaluations were tested over all MS patients. Results: Sodium intensity in MS lesions was elevated over control WM by a greater amount for NaPACMAN (75%) than NaDW (35%), the latter representing TSC. In contrast, NaSIRFLA exhibited lower intensity, but only for region specific analysis in the SCC (-7%). Sodium intensity in average MS NAWM was not significantly different than control WM for either of the three scans. NaSIRFLA in the average NAWM and specifically the posterior limb of internal capsules positively correlated with the Paced Auditory Serial Addition Test (PASAT). Discussion: Lower NaSIRFLA signal in lesions and ~2× greater NaPACMAN signal elevation over control WM than NaDW can be explained with a demyelination model that also includes edema. A NAWM demyelination model that includes tissue atrophy suggests no signal change for NaSIRFLA, and only slightly greater NAWM signal than control WM for both NaDW and NaPACMAN, reflecting experimental results. Models were derived from previous total and myelin water fraction study in MS with T2-relaxometry, and for the first time include sodium within the myelin water space. Reduced auditory processing association with lower signal on NaSIRFLA cannot be explained by greater demyelination and its modeled impact on the three sodium MRI sequences. Alternative explanations include intra- or extracellular sodium concentration change. Relaxation-weighted sodium MRI in combination with sodium-density MRI may help elucidate microstructural and metabolic changes in MS.

17.
Animals (Basel) ; 12(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35011173

RESUMO

Osteoporosis is a significant public health issue around the world, with post-menopausal osteoporosis due to estrogen deficiency resulting in approximately ¾ of cases. In this study, 18 aged Merino ewes were ovariectomized, and 10 were controls. Three of the ovariectomized ewes were treated weekly with 400 mg of methylprednisolone for 5 months and three were treated weekly for 2 months, followed by a 3-month recovery period. At 2 months, five control animals and six ovariectomized animals were euthanized. At 5 months, all the remaining ewes were euthanized. Kidney samples were collected postmortem for qPCR analysis of NPT1, PTH1R, NPT2a, NPT2c, Klotho, FGFR1IIIc, VDR, CYP24A1, CYP27B1, TRPV5, TRPV6, CalD9k, CalD28k, PMCA and NCX1. Ovariectomized sheep had significantly greater VDR expression compared with other groups. Ovariectomized sheep treated with glucocorticoids for 2 months followed by euthanasia at 5 months showed significant differences in TRPV5, CYP24A1 and klotho gene expression compared to other groups. Differences in klotho expression were most marked after adjustment for repeated measures (p = 0.1). Klotho is known as the "anti-aging" hormone and is involved in calcium and phosphorus metabolism. Klotho may be involved in the recovery of bone mineral density in ovariectomized sheep treated with glucocorticoids for 2 months followed by euthanasia at 5 months. Further research on the role of klotho is recommended.

18.
Metabolites ; 11(11)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34822412

RESUMO

This study aimed to examine the changes in lipid and metabolite profiles of ovariectomized (OVX) rats with diet-induced metabolic syndrome-associated osteoarthritis (MetOA) after supplementation with greenshell mussel (GSM) using an untargeted liquid chromatography-mass spectrometry (LC-MS) metabolomics approach. Ninety-six rats were fed with one of four diets: control, control supplemented with GSM + GSM, high fat/high sugar (HFHS), or high fat/high sugar enriched with GSM (HFHS + GSM). After 8 weeks on experimental diets, half of the rats in each group underwent OVX and the other half were sham operated. After being fed for an additional 28 weeks, blood samples were collected for the metabolomics analysis. Lipid and polar metabolites were extracted from plasma and analysed by LC-MS. We identified 29 lipid species from four lipid subclasses (phosphatidylcholine, lysophosphatidylcholine, diacylglycerol, and triacylglycerol) and a set of eight metabolites involved in amino acid metabolism (serine, threonine, lysine, valine, histidine, pipecolic acid, 3-methylcytidine, and cholic acid) as potential biomarkers for the effect of HFHS diet and GSM supplementation. GSM incorporation more specifically in the control diet generated significant alterations in the levels of several lipids and metabolites. Further studies are required to validate these findings that identify potential biomarkers to follow OA progression and to monitor the impact of GSM supplementation.

19.
Diagn Interv Imaging ; 102(11): 675-681, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34023232

RESUMO

PURPOSE: The purpose of this study was to develop a fast and automatic algorithm to detect and segment lymphadenopathy from head and neck computed tomography (CT) examination. MATERIALS AND METHODS: An ensemble of three convolutional neural networks (CNNs) based on a U-Net architecture were trained to segment the lymphadenopathies in a fully supervised framework. The resulting predictions were assessed using the Dice similarity coefficient (DSC) on examinations presenting one or more adenopathies. On examinations without adenopathies, the score was given by the formula M/(M+A) where M was the mean adenopathy volume per patient and A the volume segmented by the algorithm. The networks were trained on 117 annotated CT acquisitions. RESULTS: The test set included 150 additional CT acquisitions unseen during the training. The performance on the test set yielded a mean score of 0.63. CONCLUSION: Despite limited available data and partial annotations, our CNN based approach achieved promising results in the task of cervical lymphadenopathy segmentation. It has the potential to bring precise quantification to the clinical workflow and to assist the clinician in the detection task.


Assuntos
Aprendizado Profundo , Linfadenopatia , Humanos , Processamento de Imagem Assistida por Computador , Linfadenopatia/diagnóstico por imagem , Redes Neurais de Computação , Tomografia Computadorizada por Raios X
20.
Brain Behav ; 10(1): e01514, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31858742

RESUMO

INTRODUCTION: Diffusion tensor imaging (DTI) has shown abnormalities of the fornix and other limbic white matter tracts in multiple sclerosis (MS), mainly focusing on relapsing-remitting MS. METHODS: The goal here was to evaluate the fornix, cingulum, and uncinate fasciculus with DTI tractography at 1.7 mm isotropic resolution in three MS subgroups (11 relapsing-remitting (RRMS), nine secondary progressive (SPMS), eight primary progressive (PPMS)) versus 11 controls, and assess correlations with cognitive and clinical scores. RESULTS: The MS group overall showed extensive diffusion abnormalities of the fornix with less volume, lower fractional anisotropy (FA), and higher mean and radial diffusivities, which were similarly affected in all three MS subgroups. The uncinate fasciculus had lower FA only in the secondary progressive subgroup, and the cingulum had no DTI differences in any MS subgroup. The FA and/or volumes of these tracts correlated negatively with larger total lesion volume. The only DTI-cognitive correlation was lower right cingulum FA and greater depression over the entire MS cohort. CONCLUSIONS: Diffusion tractography identified abnormalities in the fornix that appears to be affected early and consistently across all three primary MS phenotypes of RRMS, SPMS, and PPMS regardless of Expanded Disability Status Scale, time since diagnosis, or cognitive scores.


Assuntos
Depressão , Imagem de Tensor de Difusão/métodos , Fórnice , Esclerose Múltipla , Adulto , Anisotropia , Cognição/fisiologia , Correlação de Dados , Depressão/diagnóstico , Depressão/fisiopatologia , Feminino , Fórnice/química , Fórnice/diagnóstico por imagem , Fórnice/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/classificação , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/fisiopatologia , Esclerose Múltipla/psicologia , Tamanho do Órgão
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