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1.
Atmos Environ (1994) ; 3192024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38250567

RESUMO

While pesticide vapor and particles from agricultural spray drift have been reported to pose a risk to public health, limited baseline ambient measurements exist to warrant an accurate assessment of their impacts at community-to-county-wide scale. Here, we present an initial modeling investigation of the transport and deposition of applied pesticides in an agricultural county in Arizona (Yuma County), to provide initial estimates on the corresponding enhancements in ambient levels of these spray drifts downwind of application sites. With a 50 × 50 km domain, we use the dispersion model CALPUFF with meteorology from the Weather Research and Forecasting (WRF) to investigate the spatiotemporal distribution of pesticide abundance due to spray drift from a representative sample of nine application sites. Data records for nine application days in September and October 2011, which are the peak months of pesticide application, were retroactively simulated for 48-h for all nine application sites using an active ingredient lambda-cyhalothrin, which is a commonly-used pesticide in the county. Twenty-one WRF/CALPUFF simulations were conducted with varying emissions, chemical lifetime, deposition rate, application height, and meteorology inputs, allowing for an ensemble-based analysis on the possible ranges in modeled abundance. Our results show that dispersion of vapors released at time of application heavily depends on prevailing meteorology, particularly wind speed and direction. Dispersion is limited to thin plumes that are easily transported out of the domain. The ensemble-mean vapor concentrations of the 48-h average (> 90 percentile domain-wide) range from 0.2 nanograms (ng)/m3 to 200 ng/m3, and the peak can be as high as 1000 ng/m3 near the application sites. Pesticide particles are mainly deposited within 1-2 km from the application sites at an average rate of 106 ng/km2/h but vary with particle mean diameter and standard deviation. While these findings are generally consistent with reported ambient levels in the literature, the associated ensemble-spread on these estimates are in the same order of magnitude as their ensemble-mean. At the two nearby communities downwind of these sites, we find that peak vapor concentrations are less than 50 ng/m3 with exposure times of less than an hour, as approximately 99.4% of the vapors are advected out and 99.5% of the particles deposit within the domain. Results of this study indicate pesticide spray drift from a sample of application sites and representative days in Fall may have a limited impact on neighboring communities. However, we strongly suggest that field measurements should be collected for model validation and more rigorous investigation of the actual scale of these impacts when the bulk of pesticide applications across the county, variation in active pesticide ingredients, and potential resuspension of deposited particles are considered.

2.
BMC Med Imaging ; 24(1): 75, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549082

RESUMO

BACKGROUND: Based on a longitudinal cohort design, the aim of this study was to investigate whether individual-based 18F fluorodeoxyglucose positron emission tomography (18F-FDG-PET) regional signals can predict dementia conversion in patients with mild cognitive impairment (MCI). METHODS: We included 44 MCI converters (MCI-C), 38 non-converters (MCI-NC), 42 patients with Alzheimer's disease with dementia, and 40 cognitively normal controls. Data from annual cognitive measurements, 3D T1 magnetic resonance imaging (MRI) scans, and 18F-FDG-PET scans were used for outcome analysis. An individual-based FDG-PET approach was applied using seven volumes of interest (VOIs), Z transformed using a normal FDG-PET template. Hypometabolism was defined as a Z score < -2 of regional standard uptake value ratio. For the longitudinal cognitive test scores, generalized estimating equations were used. A linear mixed-effects model was used to compare the temporal impact of cortical hypometabolism and cortical thickness degeneration. RESULTS: The clinical follow-up period was 6.6 ± 3.8 years (range 3.1 to 16.0 years). The trend of cognitive decline could differentiate MCI-C from MCI-NC after 3 years of follow-up. In the baseline 18F-FDG-PET scan of the patients with MCI, medial temporal lobe (MTL; 94.7% sensitivity, 80.5% specificity) and posterior cingulate cortex (PCC; 89.5% sensitivity, 73.1% specificity) hypometabolism predicted conversion with high accuracy. 18F-FDG-PET hypometabolism preceded dementia conversion at an interval of 3.70 ± 1.68 years and was earlier than volumetric changes, with the exception of the MTL. CONCLUSIONS: Our finding supports the use of individual-based 18F-FDG-PET analysis to predict MCI conversion to dementia. Reduced FDG-PET metabolism in the MTL and PCC were strongly associated with future cognitive decline in the MCI-C group. Changes in 18F-FDG-PET occurred 1 to 8 years prior to conversion to dementia. Progressive hypometabolism in the PCC, precuneus and lateral temporal lobe, but not MTL, preceded MRI findings at the MCI stage.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Fluordesoxiglucose F18 , Progressão da Doença , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-38864501

RESUMO

BACKGROUND: Tau-first cognitive proteinopathy (TCP) denotes a clinical phenotype of Alzheimer disease (AD) showing Florzolotau(18F) positron emission tomography (PET) positivity but a negative amyloid status. AIM: We explored the biological property of tau using longitudinal cognitive and neuroimaging data in TCP and compared with late-onset AD (LOAD). METHOD: We enrolled 56 patients with LOAD, 34 patients with TCP, and 26 cognitive unimpaired controls. All of the participants had historical data of 2 to 4 three-dimensional T1 images and 2 to 6 annual cognitive evaluations over a follow-up period of 7 years. Tau topography was measured using Florzolotau(18F) PET. In the LOAD and TCP groups, we constructed tau or gray matter clusters covarying with the cognitive measurements. We used mediator analysis to explore the regional tau load as predictor, gray matter partitions as mediators, and significant cognitive test scores as outcomes. Longitudinal cognitive decline and cortical thickness degeneration pattern were analyzed using a linear mixed-effects model. RESULTS: The TCP group had longitudinal declines in nonexecutive domains. The deterministic factor predicting the short-term memory score in TCP was the hippocampal volume and not directly via the medial and lateral temporal tau load. These features formed the conceptual differences with LOAD. DISCUSSION: The biological properties of tau and the longitudinal cognitive-imaging trajectory support the conceptual distinction between TCP and LOAD. TCP represents one specific entity featuring salient short-term memory impairment, declines in nonexecutive domains, a slower gray matter degenerative pattern, and a restricted impact of tau.

4.
Int J Mol Sci ; 25(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38891795

RESUMO

The purpose of this study was to investigate whether plasma biomarkers can help to diagnose, differentiate from Alzheimer disease (AD), and stage cognitive performance in patients with positron emission tomography (PET)-confirmed primary age-related tauopathy, termed tau-first cognitive proteinopathy (TCP) in this study. In this multi-center study, we enrolled 285 subjects with young-onset AD (YOAD; n = 55), late-onset AD (LOAD; n = 96), TCP (n = 44), and cognitively unimpaired controls (CTL; n = 90) and analyzed plasma Aß42/Aß40, pTau181, neurofilament light (NFL), and total-tau using single-molecule assays. Amyloid and tau centiloids reflected pathological burden, and hippocampal volume reflected structural integrity. Receiver operating characteristic curves and areas under the curves (AUCs) were used to determine the diagnostic accuracy of plasma biomarkers compared to hippocampal volume and amyloid and tau centiloids. The Mini-Mental State Examination score (MMSE) served as the major cognitive outcome. Logistic stepwise regression was used to assess the overall diagnostic accuracy, combining fluid and structural biomarkers and a stepwise linear regression model for the significant variables for MMSE. For TCP, tau centiloid reached the highest AUC for diagnosis (0.79), while pTau181 could differentiate TCP from YOAD (accuracy 0.775) and LOAD (accuracy 0.806). NFL reflected the clinical dementia rating in TCP, while pTau181 (rho = 0.3487, p = 0.03) and Aß42/Aß40 (rho = -0.36, p = 0.02) were significantly correlated with tau centiloid. Hippocampal volume (unstandardized ß = 4.99, p = 0.01) outperformed all of the fluid biomarkers in predicting MMSE scores in the TCP group. Our results support the superiority of tau PET to diagnose TCP, pTau181 to differentiate TCP from YOAD or LOAD, and NFL for functional staging.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Biomarcadores , Tomografia por Emissão de Pósitrons , Proteínas tau , Humanos , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/diagnóstico , Proteínas tau/sangue , Biomarcadores/sangue , Masculino , Feminino , Tomografia por Emissão de Pósitrons/métodos , Idoso , Peptídeos beta-Amiloides/sangue , Pessoa de Meia-Idade , Cognição , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Hipocampo/metabolismo , Proteínas de Neurofilamentos/sangue , Idoso de 80 Anos ou mais , Amnésia/sangue , Amnésia/diagnóstico por imagem , Amnésia/diagnóstico , Curva ROC , Relevância Clínica
5.
Eur Spine J ; 32(10): 3413-3424, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563485

RESUMO

PURPOSE: To elucidate whether pro-inflammatory cytokines might influence the commitment of intervertebral disc (IVD)- and ligamentum flavum (LF)-derived progenitor cells toward either osteogenesis or adipogenesis, specifically Interleukin-1ß (IL-1ß), IL-19, and IL-20. METHODS: Sixty patients with degenerative spondylolisthesis and lumbar or lumbosacral spinal stenosis were included in the study. Injuries to the spine, infections, and benign or malignant tumors were excluded. From nine patient samples, IVD- and LF-derived cells were isolated after primary culture, and two clinical samples were excluded due to mycoplasma infection. The effects of IL-1ß, IL-19, as well as IL-20 in regulating osteogenic and adipogenic differentiation in vitro were investigated. RESULTS: Primary IVD- and LF-derived cells were found to have a similar cell morphology and profile of surface markers (CD44, CD90, and CD105) as placenta-derived mesenchymal stem cells (MSCs). Primary IVD/LF cells have a high capacity to differentiate into osteocytes and adipocytes. IL-19 had a tendency to promote adipogenesis. IL-20 inhibited osteogenesis and promoted adipogenesis; IL-1ß promoted osteogenesis but inhibited adipogenesis. CONCLUSION: IL-1ß, IL-19, and IL-20 impact the adipogenic and osteogenic differentiation of IVD-derived and LF-derived cells. Modulating the expression of IL-1ß, IL-19, and IL-20 provides a potential avenue for controlling cell differentiation of IVD- and LF-derived cells, which might have beneficial effect for degenerative spondylolisthesis and spinal stenosis.


Assuntos
Ligamento Amarelo , Estenose Espinal , Espondilolistese , Humanos , Adipogenia , Osteogênese , Interleucina-1beta/farmacologia , Estenose Espinal/patologia , Ligamento Amarelo/patologia , Espondilolistese/patologia , Diferenciação Celular , Células-Tronco
6.
Psychiatry Clin Neurosci ; 77(7): 401-409, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37097074

RESUMO

BACKGROUND: The diffusion tensor imaging analysis along the perivascular space (ALPS)-index can be used to model the glymphatic system in vivo. AIM: This study explores putative mechanisms between prediction of ALPS-index and cognitive outcomes in young-onset Alzheimer's disease (YOAD) and age-matched controls (CTLs) and analyzes whether the link was mediated by the integrity of ALPS-index-anchored cerebral gray matter (GM). METHODS: We enrolled 130 patients with YOAD and 137 CTLs. All participants underwent three-dimensional T1 -weighted MRI, diffusion tensor imaging and cognitive tests. We constructed GM regions correlated with the ALPS-index in the YOAD and CTL groups. For the GM regions significantly correlated with the ALPS-index and cognitive measures, we extracted a 4-mm radius sphere. In the YOAD and CTL groups, we used mediator analysis to explore the ALPS-index as predictor, GM partitions as mediators, and significant cognitive test scores as outcomes. RESULTS: Patient group had significantly lower ALPS-index. The ALPS-index was associated with GM volume in the cerebellar gray, dorsolateral prefrontal, thalamus, superior frontal, amygdala and hippocampus, and these coherent regions coincided with those showing GM atrophy in the YOAD group. Mediation analysis of the YOAD group suggested that the relationships between the ALPS-index and cognitive performance were fully mediated by the integrity of ALPS-index coherent GM areas. DISCUSSION: Reserved GM mediates the link between the glymphatic system and cognition. Our findings suggest that GM integrity rather than the glymphatic system could serve as a direct cognitive test scores predictor in patients with YOAD.


Assuntos
Doença de Alzheimer , Sistema Glinfático , Humanos , Substância Cinzenta/diagnóstico por imagem , Imagem de Tensor de Difusão , Doença de Alzheimer/diagnóstico por imagem , Sistema Glinfático/diagnóstico por imagem , Córtex Cerebral
7.
Saudi Pharm J ; 31(6): 1109-1114, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37293378

RESUMO

Osteoarthritis is a disease associated with articular cartilage degradation, intra-articular area inflammation, and subchondral bone replacement. Cytokine IL-1ß has a prominent function in the inflammations process that passes in the joints. The 70% ethanol extracts of deer antler (250 and 500 mg/kg BW) and glucosamine sulfate (250 kg/BW) were evaluated for four weeks in reducing cytokine IL-1ß to rat model OA-induced Monosodium iodoacetate. Measurements of joint diameter in rat's knee and hyperalgesia were performed on weeks 0, 1, 2, 3, 4, 5, 6, and 7. The presence of a significant difference in the stimulation thermal latency (p = 0.00) and the resulting increase in swelling of joint diameter (p = 0.00) are evidence that MIA has successfully induced the rat modeling of OA. A significant decrease in cytokine IL-Iß levels was shown on week 3 after MIA injection (p = 0.00). Both concentrations of deer extracts significantly reduced knee joint diameter (p = 0.00), latency thermal stimulation (p = 0.00), and cytokine IL-1ß levels (p = 0.00). Based on the results, it can be concluded that the 70% ethanol extract of deer antler is a potential medicine for OA therapy.

8.
Int J Mol Sci ; 23(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35887297

RESUMO

Excessive mechanical loading is a major cause of spinal degeneration, typically originating from a tear in the annulus fibrosus (AF). Endoplasmic reticulum (ER) stress and NLRP3 (NOD-, LRR- and pyrin domain-containing protein 3) inflammasome have been implicated in the pathogenesis of intervertebral disc (IVD) degeneration. However, the causal relationship between the mechanical stretching of AF cells and the NLRP3 inflammasome response associated with ER stress remains scarce. To elucidate the pathogenesis and regulatory mechanisms of mechanical stretch-induced IVD degeneration, human AF cell lines were subjected to different degrees of cyclic stretching to simulate daily spinal movements. Our results indicated that 15% high cyclic stretch (HCS) induced the expression of NLRP3 and interleukin-1 beta (IL-1ß) and was also responsible for the increased expression of NADPH (nicotinamide adenine dinucleotide phosphate) oxidase 2 (NOX2) and reactive oxygen species (ROS) in human AF cells. In addition, HCS increased the expression of glucose-regulated protein 78 (GRP78), an ER stress chaperone, which was neutralized with tauroursodeoxycholic acid (TUDCA), an ER stress inhibitor. In addition, HCS was found to induce thioredoxin-interacting protein (TXNIP) expression and NLRP3 inflammasome activation, which can be suppressed by si-NOX2 or the NOX2 inhibitor GSK2795039. Consequently, HCS upregulated ER stress and ROS production, leading to increased NLRP3 and IL-1ß expression in human AF cells, and may further accelerate IVD degeneration.


Assuntos
Anel Fibroso , Degeneração do Disco Intervertebral , Anel Fibroso/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Degeneração do Disco Intervertebral/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
Int J Mol Sci ; 23(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36498962

RESUMO

The amyloid framework forms the central medical theory related to Alzheimer disease (AD), and the in vivo demonstration of amyloid positivity is essential for diagnosing AD. On the basis of a longitudinal cohort design, the study investigated clinical progressive patterns by obtaining cognitive and structural measurements from a group of patients with amnestic mild cognitive impairment (MCI); the measurements were classified by the positivity (Aß+) or absence (Aß-) of the amyloid biomarker. We enrolled 185 patients (64 controls, 121 patients with MCI). The patients with MCI were classified into two groups on the basis of their [18F]flubetaben or [18F]florbetapir amyloid positron-emission tomography scan (Aß+ vs. Aß-, 67 vs. 54 patients) results. Data from annual cognitive measurements and three-dimensional T1 magnetic resonance imaging scans were used for between-group comparisons. To obtain longitudinal cognitive test scores, generalized estimating equations were applied. A linear mixed effects model was used to compare the time effect of cortical thickness degeneration. The cognitive decline trajectory of the Aß+ group was obvious, whereas the Aß- and control groups did not exhibit a noticeable decline over time. The group effects of cortical thickness indicated decreased entorhinal cortex in the Aß+ group and supramarginal gyrus in the Aß- group. The topology of neurodegeneration in the Aß- group was emphasized in posterior cortical regions. A comparison of the changes in the Aß+ and Aß- groups over time revealed a higher rate of cortical thickness decline in the Aß+ group than in the Aß- group in the default mode network. The Aß+ and Aß- groups experienced different APOE ε4 effects. For cortical-cognitive correlations, the regions associated with cognitive decline in the Aß+ group were mainly localized in the perisylvian and anterior cingulate regions. By contrast, the degenerative topography of Aß- MCI was scattered. The memory learning curves, cognitive decline patterns, and cortical degeneration topographies of the two MCI groups were revealed to be different, suggesting a difference in pathophysiology. Longitudinal analysis may help to differentiate between these two MCI groups if biomarker access is unavailable in clinical settings.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Tomografia por Emissão de Pósitrons/métodos , Amiloide , Cognição , Córtex Entorrinal/metabolismo , Proteínas Amiloidogênicas , Biomarcadores
10.
J Cell Physiol ; 234(1): 958-968, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-30132856

RESUMO

The shear force effect on human chondrocytes is time and magnitude dependent. Recently, kruppel-like factor (KLF) 4 has been identified as a pleiotropic protein and its activity in cells is dependent on different stimuli and/or cell types. The role of KLF4 in chondrocytes is still unclear and there has been no report determining whether shear force regulates KLF4 levels in chondrocytes. Hence, this study was carried out to investigate the role of KLF4 in human chondrocytes under shear force stimulation and the underlying mechanism. Human primary and SW1353 chondrocytes were used in this study. The shear forces at 2, 5, or 15 dyn/cm2 intensity were applied to both types of human chondrocytes. The specific small interfering RNAs, activators, and inhibitors were used to study the detailed mechanism of shear force. The presented results showed that 2, but not 5 and 15, dyn/cm2 shear force increases KLF4 expression in human primary and SW1353 chondrocytes. Extracellular signal-regulated kinase 5 induced peroxisome proliferator-activated receptor γ transcription activity to increase KLF4 transcription. Moreover, the KLF4 induction in human chondrocytes in response to 2 dyn/cm2 shear force could attenuate interleukin (IL)-1ß-stimulated nuclear factor-κB activation. These results elucidate the role of KLF4 in antagonizing the effect of IL-1ß in human chondrocytes under 2 dyn/cm2 shear force stimulation and provide a possible mechanism to demonstrate the protection of moderate forces or exercises in cartilage.


Assuntos
Condrócitos/citologia , Interleucina-1beta/genética , Fatores de Transcrição Kruppel-Like/genética , Osteoartrite/genética , Cartilagem/crescimento & desenvolvimento , Cartilagem/metabolismo , Condrócitos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Fator 4 Semelhante a Kruppel , Proteína Quinase 7 Ativada por Mitógeno/genética , NF-kappa B/genética , Osteoartrite/patologia , PPAR gama/genética , Cultura Primária de Células , RNA Interferente Pequeno/genética , Estresse Mecânico , Ativação Transcricional/genética
11.
J Cell Biochem ; 119(8): 6943-6952, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29737584

RESUMO

Colorectal cancer (CRC) is the fourth most common cause of cancer death worldwide. Chemotherapy has been the major strategy for treating patients with advanced CRC. Oxaliplatin (OXA) is used as both an adjuvant and neoadjuvant anticancer agent available to treat advanced CRC. High-mobility group box 1 protein (HMGB1) is a critical regulator of cell death and survival. HMGB1 overexpression has been shown to be resistant to cytotoxic agents. In addition, Metformin, a widely used drug for diabetes, has emerged as a potential anticancer agent. In this study, we examined whether HMGB1 plays a role in the OXA- and/or metformin-induced cytotoxic effect on CRC cells. The results showed that treatment with OXA increased HMGB1 expression in the ERK1/2- and Akt-dependent manners in DLD-1 cells. HMGB1 gene knockdown enhanced the cytotoxicity and cell growth inhibition of OXA. Moreover, OXA-increased HMGB1 expression was by inducing NF-κB-DNA-binding activity to in DLD-1 cells. Compared to a single agent, OXA combined with metformin administration resulted in cytotoxicity and cell growth inhibition synergistically, accompanied with reduced HMGB1 level. These findings may have implications for the rational design of future drug regimens incorporating OXA and metformin for the treatment of CRC.


Assuntos
Neoplasias Colorretais/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteína HMGB1/biossíntese , Metformina/farmacologia , Proteínas de Neoplasias/biossíntese , Oxaliplatina/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/dietoterapia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteína HMGB1/genética , Humanos , Metformina/agonistas , Proteínas de Neoplasias/genética , Oxaliplatina/agonistas
12.
J Cell Biochem ; 119(4): 3716-3724, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29236309

RESUMO

The induction of bone morphogenetic protein (BMP)2 in injured and arthritis articular cartilage has been proposed, but the precise mechanism has not been clearly clarified. Our previous study has found that leptin could stimulate the BMP2 autocrine effect to increase the anabolic collagen II expression when it initiates the catabolic response in human chondrocytes. It has been suggested that this BMP2 autocrine effect contributes to a reparative role in leptin-stimulated human chondrocytes. In this study, we further determined whether this BMP2 autocrine effect also affect the expressions of catabolic matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase with thrombospondin motif (ADAMTS). Human primary and SW1353 chondrocytes were used in this study. It was shown that leptin could induce the expressions of MMP1, 3, and 13 and ADAMTS4 and 5 in both human primary and SW1353 chondrocytes. Leptin-increased MMP1/13 (not MMP3) and ADAMTS4 (not ADAMTS5) expressions were affected by the leptin-upregulated BMP2 and its specific downstream Smad1/5 signaling. Moreover, both HDAC3 and 4 are involved in regulating leptin-induced BMP2 upregulation and then affect MMP1 and 13 and ADAMTS4 expression. Both HDAC3 and 4 also affect leptin-increased MMP3 mRNA expression but not through BMP2 autocrine effect of leptin induction. Our results further elucidated the role of BMP2 autocrine effect in matrix-degrading enzymes expressions under leptin stimulation. The findings in this study provide new insights into the possible mechanism of BMP2 induction in leptin-stimulated chondrocytes and in leptin-induced OA development.


Assuntos
Proteína ADAMTS4/metabolismo , Proteína Morfogenética Óssea 2/metabolismo , Condrócitos/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Proteína ADAMTS4/genética , Western Blotting , Proteína Morfogenética Óssea 2/genética , Ensaio de Imunoadsorção Enzimática , Humanos , Leptina , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 13 da Matriz/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteína Smad1/genética , Proteína Smad1/metabolismo , Proteína Smad5/genética , Proteína Smad5/metabolismo
13.
Molecules ; 23(1)2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29301300

RESUMO

Recent studies have demonstrated that fat accumulation in bone cells is detrimental to bone mass. Both adipocytes and osteoblasts are derived from common multipotent mesenchymal stem cells (MSCs) and hence the presence of fat may increase adipocyte proliferation, differentiation and fat accumulation while inhibiting osteoblast differentiation and bone formation. Lipids are common constituents in supramolecular vesicles (e.g., micelles or liposomes) that serve as drug delivery systems. Liposomal formulations such as Meriva® were proven to decrease joint pain and improve joint function in osteoarthritis (OA) patients. In this study, we evaluated how lipid types and liposomal formulations affect osteoblast behavior including cell viability, differentiation, mineralization and inflammation. Various liposomal formulations were prepared using different types of lipids, including phosphatidylcholine (PC), 1,2-dioleoyl-sn-glycero-3-phospho-ethanolamine (DOPE), cholesterol (Chol), 3ß-[N-(N',N'-dimethylaminoethane)-carbamoyl] cholesterol hydrochloride (DC-cholesterol HCl), and 1,2-dioleoyl-3-trimethylammonium-propane chloride salt (DOTAP) to investigate the impact on osteoblast differentiation and inflammation. The results indicated that cationic lipids, DC-cholesterol and DOTAP, presented higher dose-dependent cytotoxicity and caused high level of inflammatory responses. Due to the natural properties of lipids, all the lipids can induce lipid droplet formation in osteoblasts but the level of lipid droplet accumulation was different. In comparison with cationic lipids, neutral lipids induced less adiposity, and maintained high osteoblast mineralization. Similar to previous researches, we also confirmed an inverse relationship between lipid droplet formation and osteoblast mineralization in 7F2 mouse osteoblasts. Importantly, PC containing liposomes (PC only and PC/DOTAP) suppressed IL-1ß-induced gene expression of COX-2 and MMP-3 but not Chol/DOTAP liposomes or DC-Chol/DOPE liposomes. Taken together, we suggested that PC contained liposomes could provide the best liposomal formulation for the treatment of bone diseases.


Assuntos
Lipídeos/química , Lipossomos/química , Lipossomos/farmacologia , Osteoblastos/efeitos dos fármacos , Animais , Calcificação Fisiológica/efeitos dos fármacos , Cátions/química , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colesterol/química , Ciclo-Oxigenase 2/genética , Sistemas de Liberação de Medicamentos/métodos , Ácidos Graxos Monoinsaturados/química , Gotículas Lipídicas/química , Lipídeos/farmacologia , Metaloproteinase 3 da Matriz/genética , Camundongos , Osteoblastos/fisiologia , Osteogênese/efeitos dos fármacos , Fosfatidilcolinas/química , Compostos de Amônio Quaternário/química
14.
J Cell Physiol ; 232(10): 2741-2749, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28218386

RESUMO

Osteoarthritis (OA) is currently still an irreversible degenerative disease of the articular cartilage. Recent, dextrose (d-glucose) intraarticular injection prolotherapy for OA patients has been reported to benefit the chondrogenic stimulation of damaged cartilage. However, the detailed mechanism of glucose's effect on cartilage repair remains unclear. Chitosan, a naturally derived polysaccharide, has recently been investigated as a surgical or dental dressing to control breeding. Therefore, in this study, glucose was adsorbed to chitosan membranes (CTS-Glc), and the study aimed to investigate whether CTS-Glc complex membranes could regulate the proliferation of human OA chondrocytes and to explore the underlying mechanism. Human OA and SW1353 chondrocytes were used in this study. The experiments involving the transfection of cells used SW1353 chondrocytes. A specific inhibitor and siRNAs were used to investigate the mechanism underlying the CTS-Glc-regulated proliferation of human chondrocytes. We found that CTS-Glc significantly increased the proliferation of both human OA and SW1353 chondrocytes comparable to glucose- or chitosan-only stimulation. The role of mammalian target of rapamycin complex 1 (mTORC1) signaling, including mTOR, raptor, and S6k proteins, has been demonstrated in the regulation of CTS-Glc-increased human chondrocyte proliferation. mTORC1 signaling increased the expression levels of maturated SREBP-1 and FASN and then induced the expressions of cell cycle regulators, that is, cyclin D, cyclin-dependent kinase-4 and -6 in human chondrocytes. This study elucidates the detailed mechanism behind the effect of CTS-Glc complex membranes in promoting chondrocyte proliferation and proposes a possible clinical application of the CTS-Glc complex in the dextrose intraarticular injection of OA prolotherapy in the future to attenuate the pain and discomfort of OA patients.


Assuntos
Antirreumáticos/farmacologia , Proliferação de Células/efeitos dos fármacos , Quitosana/farmacologia , Condrócitos/efeitos dos fármacos , Glucose/farmacologia , Membranas Artificiais , Complexos Multiproteicos/metabolismo , Osteoartrite/tratamento farmacológico , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adsorção , Idoso , Antirreumáticos/química , Técnicas de Cultura de Células , Linhagem Celular , Quitosana/química , Condrócitos/enzimologia , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , Ácido Graxo Sintase Tipo I/metabolismo , Feminino , Glucose/química , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Pessoa de Meia-Idade , Complexos Multiproteicos/antagonistas & inibidores , Complexos Multiproteicos/genética , Osteoartrite/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Proteína Regulatória Associada a mTOR , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Fatores de Tempo , Transfecção , Homólogo LST8 da Proteína Associada a mTOR
15.
J Cell Physiol ; 232(6): 1448-1457, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27731497

RESUMO

Low shear stress has been proposed to play a reparative role in modulating cartilage homeostasis. Recently, epidemiological studies have found a positive correlation between the resistin level in serum and synovial fluid and osteoarthritis (OA) severity in patients. However, the effect of moderate shear stress on the catabolic stimulation of resistin in OA chondrocytes remains unclear. Hence, this study was to investigate whether low shear stress could regulate resistin-induced catabolic cyclooxygenase (COX)-2 expression in human OA chondrocytes and the underlying mechanism. Human OA chondrocytes and SW1353 chondrosarcoma cells were used in this study. Two modes of low shear stress (2 dyn/cm2 ), pre-shear and post-shear, were applied to the chondrocytes. A specific activator and siRNAs were used to investigate the mechanism of low shear stress-regulated COX-2 expression of resistin induction. We found that human OA chondrocytes exposed to different modes of low shear stress elicit an opposite effect on resistin-induced COX-2 expression: pre-shear for a short duration attenuates the resistin effect by inhibiting the transcription factor nuclear factor (NF)-κB-p65 subunit and the cAMP response element binding protein; however, post-shear over a longer duration enhances the resistin effect by activating only the NF-κB-p65 subunit. Moreover, our results demonstrated that the regulation of both shear modes in resistin-stimulated COX-2 expression occurs through increasing AMP-activated protein kinase activation and then sirtuin 1 expression. This study elucidates the detailed mechanism of low shear stress regulating the resistin-induced catabolic COX-2 expression and indicates a possible reparative role of moderate shear force in resistin-stimulated OA development. J. Cell. Physiol. 232: 1448-1457, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Condrócitos/enzimologia , Ciclo-Oxigenase 2/genética , Osteoartrite/enzimologia , Osteoartrite/patologia , Resistina/farmacologia , Estresse Mecânico , Proteínas Quinases Ativadas por AMP/metabolismo , Idoso , Linhagem Celular Tumoral , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ciclo-Oxigenase 2/metabolismo , Humanos , Pessoa de Meia-Idade , Modelos Biológicos , NF-kappa B/metabolismo , Osteoartrite/genética , Regiões Promotoras Genéticas/genética , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo
16.
Int J Mol Sci ; 17(7)2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27428951

RESUMO

Adiponectin is one of the most abundant adipokines from the subcutaneous fat, and regulates multiple activities through endocrine, paracrine, or autocrine mechanisms. However, its expression in adipogenic induced fibroblasts, and the potential role in photoaging has not been determined. Here, human dermal fibroblasts, Hs68, were presented as a cell model of dermal lipogenesis through stimulation of adipogenic differentiation medium (ADM). Similar to other studies in murine pre-adipocyte models (i.e., 3T3-L1), Hs68 fibroblasts showed a tendency to lipogenesis based on lipid accumulation, triglyceride formation, and the expressions of PPAR-γ, lipoprotein lipase (LPL), and FABP4 mRNA. As expected, ADM-treated fibroblasts displayed a reduction on adiponectin expression. Next, we emphasized the photoprotective effects of adiponectin against UVA-induced damage in Hs68 fibroblasts. UVA radiation can downregulate cell adhesion strength and elastic modulus of Hs68 fibroblasts. Moreover, UVA radiation could induce the mRNA expressions of epidermal growth factor receptor (EGFR), adiponectin receptor 1 (AdipoR1), matrix metalloproteinase-1 (MMP-1), MMP-3, and cyclooxygenase-2 (COX-2), but downregulate the mRNA expressions of type I and type III collagen. On the other hand, post-treatment of adiponectin can partially overcome UVA-induced reduction in the cell adhesion strength of Hs68 fibroblasts through the activation of AdipoR1 and the suppression of EGF-R. In addition, post-treatment of adiponectin indicated the increase of type III collagen and elastin mRNA expression and the decrease of MMP-1 and MMP-3 mRNA expression, but a limited degree of recovery of elastic modulus on UVA-irradiated Hs68 fibroblasts. Overall, these results suggest that dermal lipogenesis may inhibit the expression of adiponectin while exogenous adiponectin administration prevents against UVA-induced dermal matrix degradation in Hs68 fibroblasts.


Assuntos
Adiponectina/metabolismo , Fibroblastos/fisiologia , Lipogênese/fisiologia , Dermatopatias/prevenção & controle , Pele/efeitos da radiação , Raios Ultravioleta , Adiponectina/administração & dosagem , Adiponectina/genética , Apoptose/efeitos da radiação , Western Blotting , Adesão Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Células Cultivadas , Fibroblastos/efeitos da radiação , Imunofluorescência , Humanos , Lipogênese/efeitos da radiação , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Dermatopatias/metabolismo , Dermatopatias/patologia
17.
Nutrients ; 16(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38474861

RESUMO

BACKGROUND & AIMS: Low plasma B12 and folate levels or hyperhomocysteinemia are related to cognitive impairment. This study explores the relationships among diet pattern, blood folate-B12-homocysteine levels, and cognition measurement in Alzheimer's disease (AD) while exploring whether a gender effect may exist. METHODS: This cross-sectional study enrolled 592 AD patients (246 males, 346 females) and the demographic data, blood biochemical profiles, Mini-Mental State Examination (MMSE), and a Food Frequency Questionnaire (FFQ) for quantitative assessment of dietary frequency were collected. Structural Equation Modeling (SEM) was employed to explore the associations among dietary patterns, blood profiles, and cognition. A least absolute shrinkage and selection operator regression model, stratified by gender, was constructed to analyze the weighting of possible confounders. RESULTS: Higher MMSE scores were related to higher frequencies of coffee/tea and higher educational levels, body mass index, and younger age. The SEM model revealed a direct influence of dietary frequencies (skimmed milk, thin pork, coffee/tea) and blood profiles (homocysteine, B12, and folate) on cognitive outcomes. At the same time, the influence of dietary pattern on cognition was not mediated by folate-B12-homocysteine levels. In males, a direct influence on the MMSE is attributed to B12, while in females, homocysteine is considered a more critical factor. CONCLUSIONS: Dietary patterns and blood profiles are both associated with cognitive domains in AD, and there are gender differences in the associations of dietary patterns and the levels of B12 and homocysteine. To enhance the quality of dietary care and nutritional status for individuals with dementia, our study results still require future validations with multi-center and longitudinal studies.


Assuntos
Doença de Alzheimer , Ácido Fólico , Masculino , Feminino , Humanos , Doença de Alzheimer/psicologia , Estudos Transversais , Fatores Sexuais , Café , Vitamina B 12 , Dieta , Cognição , Chá , Homocisteína
18.
J Parkinsons Dis ; 13(2): 243-254, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36776077

RESUMO

BACKGROUND: A better understanding of factors associated with caregiver burden might facilitate the construction of coping strategies to improve their clinical outcomes and the comprehensive care model for dementia. OBJECTIVE: To investigate the cognitive and neuropsychiatric domains that contribute to caregiver burden in three types of neurodegenerative disorders: Parkinson's disease (PD), Alzheimer's disease (AD), and frontotemporal disease (FTD). METHODS: Eight hundred and fourteen patients and their caregivers were invited to participate; among them, 235 had PD with cognitive impairment; 429 had AD, and 150 had FTD. The evaluation protocol included the Neuropsychiatric Inventory (NPI), the Mini-Mental State Examination, the Chinese Version Verbal Learning Test, the modified Trail Making Test B, semantic fluency, and a geriatric depression score. Statistical comparisons of the cognitive tests, NPI total scores, and caregiver burden among the three diagnosed types of dementia, matched for a Clinical Dementia Rating (CDR) of 0.5 or 1, were performed, and multivariate linear regression models were used to evaluate the parameter significance. RESULTS: Caregivers for patients with PD and FTD showed significant burden increments when the CDR scores changes from 0.5 to 1. For CDR = 0.5, the PD group had significantly lower caregiver burdens than the AD group, but the NPI total scores were significantly higher. Factors related to caregiver burden were the presence of delusion among all diagnosis groups, while the impact of NPI total scores related to caregiver burden was the highest in FTD, followed by AD and PD. CONCLUSIONS: At the mild to moderate stages, our results suggested different degrees of significance in terms of the cognitive test scores or NPI subdomains for predicting caregiver stress among the three types of dementia.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Demência Frontotemporal , Doença de Parkinson , Humanos , Idoso , Doença de Alzheimer/complicações , Cuidadores/psicologia , Demência Frontotemporal/complicações , Demência Frontotemporal/psicologia , Doença de Parkinson/complicações , Disfunção Cognitiva/etiologia , Testes Neuropsicológicos
19.
Neuroscience ; 524: 11-20, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37030632

RESUMO

The glymphatic system is a fluid-clearance pathway that clears cerebral waste products, and its dysfunction has been associated with protein aggregation diseases such as Alzheimer's disease. To understand how the glymphatic system changes with aging, we enrolled 433 cognitive unimpaired participants (236 women and 197 men, 13-88 years) and evaluated the glymphatic function by calculating diffusion tensor imaging analysis along the perivascular space (ALPS) index and explored how the ALPS index is associated with cortical atrophy and cognitive decline in older people. We found a significant inverse correlation between ALPS index and age (ρ = -0.45, p < 0.001), with a peak value in people in their thirties. A higher ALPS index indicated a better cortical reserve in regions coincided with the default mode network. Declines in mental manipulation and short-term memory performance in the older participants were associated with a lower ALPS index and cortical atrophy in the amygdala, anterior and posterior cingulate, thalamus and middle frontal regions. Our findings highlight that the ALPS index could be used to evaluate brain reserve and cognitive reserve in older people.


Assuntos
Reserva Cognitiva , Sistema Glinfático , Masculino , Humanos , Feminino , Idoso , Imagem de Tensor de Difusão/métodos , Cognição , Envelhecimento
20.
Int J Pharm ; 637: 122868, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-36958606

RESUMO

Follicle stimulating hormone (FSH) is widely used for the treatment of female infertility, where the level of FSH is suboptimal due to which arrest in follicular development and anovulation takes place. Currently, only parenteral formulations are available for FSH in the market. Due to the drawbacks of parenteral administration and the high market shares of FSH, there is a need for easily accessible oral formulation. Therefore, enteric coated capsules filled with FSH loaded nanostructured lipid carriers (NLCs) or liposomes were prepared. Preliminary studies such as circular dichroism, SDS-PAGE, FTIR and ELISA were conducted to analyze FSH. Prepared formulations were optimized with respect to the size, polydispersity index, zeta potential, and entrapment efficiency using the design of experiments. Optimized formulations were subjected to particle counts and distribution analysis, TEM analysis, in vitro drug release, dissolution of enteric coated capsules, cell line studies, everted sac rat's intestinal uptake study, pharmacokinetics, pharmacodynamics, and stability studies. In the case of liposomes, RGD conjugation was done by carbodiimide chemistry and conjugation was confirmed by FTIR, 1HNMR and Raman spectroscopy. The prepared formulations were discrete and spherical. The release of FSH from enteric coated capsules was slow and sustained. The increased permeability of nano-formulations was observed in Caco-2 monoculture as well as in Caco-2 and Raji-B co-culture models. NLCs and liposomes showed an improvement in oral bioavailability and efficacy of FSH in rats. This may be due to mainly chylomicron-assisted lymphatic uptake of NLCs; whereas, in the case of liposomes, RGD-based targeting of ß1 integrins of M cells on Peyer's patches may be the main reason for the better effect by FSH. FSH was found to be stable chemically and conformationally. Overall, the study reveals the successful development and evaluation of FSH loaded NLCs and liposomes.


Assuntos
Portadores de Fármacos , Nanoestruturas , Humanos , Ratos , Feminino , Animais , Portadores de Fármacos/química , Lipossomos , Hormônio Foliculoestimulante , Células CACO-2 , Nanoestruturas/química , Administração Oral , Cápsulas , Oligopeptídeos , Tamanho da Partícula
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