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1.
Nature ; 603(7901): 470-476, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236988

RESUMO

Alzheimer's disease has a higher incidence in older women, with a spike in cognitive decline that tracks with visceral adiposity, dysregulated energy homeostasis and bone loss during the menopausal transition1,2. Inhibiting the action of follicle-stimulating hormone (FSH) reduces body fat, enhances thermogenesis, increases bone mass and lowers serum cholesterol in mice3-7. Here we show that FSH acts directly on hippocampal and cortical neurons to accelerate amyloid-ß and Tau deposition and impair cognition in mice displaying features of Alzheimer's disease. Blocking FSH action in these mice abrogates the Alzheimer's disease-like phenotype by inhibiting the neuronal C/EBPß-δ-secretase pathway. These data not only suggest a causal role for rising serum FSH levels in the exaggerated Alzheimer's disease pathophysiology during menopause, but also reveal an opportunity for treating Alzheimer's disease, obesity, osteoporosis and dyslipidaemia with a single FSH-blocking agent.


Assuntos
Doença de Alzheimer , Hormônio Foliculoestimulante , Idoso , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Densidade Óssea , Cognição , Feminino , Hormônio Foliculoestimulante/metabolismo , Humanos , Camundongos , Termogênese
2.
EMBO J ; 42(3): e111348, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36524441

RESUMO

Moderate coolness is sensed by TRPM8 ion channels in peripheral sensory nerves, but the mechanism by which noxious cold is detected remains elusive. Here, we show that somatosensory and sympathetic neurons express two distinct mechanisms to detect noxious cold. In the first, inhibition by cold of a background outward current causes membrane depolarization that activates an inward current through voltage-dependent calcium (CaV ) channels. A second cold-activated mechanism is independent of membrane voltage, is inhibited by blockers of ORAI ion channels and by downregulation of STIM1, and is recapitulated in HEK293 cells by co-expression of ORAI1 and STIM1. Using total internal reflection fluorescence microscopy we found that cold causes STIM1 to aggregate with and activate ORAI1 ion channels, in a mechanism similar to that underlying store-operated calcium entry (SOCE), but directly activated by cold and not by emptying of calcium stores. This novel mechanism may explain the phenomenon of cold-induced vasodilation (CIVD), in which extreme cold increases blood flow in order to preserve the integrity of peripheral tissues.


Assuntos
Canais de Cálcio , Cálcio , Humanos , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Cálcio/metabolismo , Células HEK293 , Sinalização do Cálcio/fisiologia , Neurônios/metabolismo , Proteína ORAI1/genética , Molécula 1 de Interação Estromal/genética , Proteínas de Neoplasias/genética
3.
Osteoarthritis Cartilage ; 32(8): 972-981, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38710437

RESUMO

OBJECTIVE: To compare the clinical and cost effectiveness of the Collaborative Model of Care between Orthopaedics and Allied Healthcare Professionals (CONNACT), a community-based, stratified, multidisciplinary intervention consisting of exercise, education, psychological and nutrition delivered through a chronic care model to usual hospital care in adults with knee osteoarthritis (OA). METHODS: Pragmatic, parallel-arm, single-blinded superiority RCT trial. Community-dwelling, ambulant adults with knee OA (Kellgren-Lawrence grade > 1; Knee Injury and OA Outcome Score (KOOS4) ≤75) were enrolled. Primary outcome was KOOS4 at 12-months; secondary outcomes included: quality of life, physical performance measures, symptom satisfaction, psychological outcomes, dietary habits, and global perceived effect. Intention-to-treat analysis using generalized linear model (GLM) and regression modeling were conducted. Economic evaluation through a societal approach was embedded. RESULTS: 110 participants (55 control, 55 intervention) were randomized. No between-group difference found for the primary outcome (MD [95%CI]: -1.86 [-9.11. 5.38]), although both groups demonstrated within-group improvement over 12-months. Among the secondary outcomes, the CONNACT group demonstrated superior dietary change (12 months) and physical performance measures (3 months), and global perceived effect (6 months). While there was no between-group difference in total cost, significant productivity gains (reduced indirect cost) were seen in the CONNACT group. CONCLUSION: CONNACT was not superior to usual care at 1 year. Further efforts are needed to understand the underlying contextual and implementation factors in order to further improve and refine such community-based, stratified care models moving forward. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT03809975. Registered January 18, 2019. https://clinicaltrials.gov/ct2/show/NCT03809975.


Assuntos
Análise Custo-Benefício , Osteoartrite do Joelho , Humanos , Feminino , Masculino , Osteoartrite do Joelho/terapia , Osteoartrite do Joelho/reabilitação , Pessoa de Meia-Idade , Idoso , Pessoal Técnico de Saúde , Método Simples-Cego , Ortopedia , Qualidade de Vida , Equipe de Assistência ao Paciente , Terapia por Exercício/métodos
4.
J Nat Prod ; 87(2): 286-296, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38284153

RESUMO

Nine new alkaloids, eugeniinalines A-H (1-8) and (+)-eburnamenine N-oxide (9), comprising one quinoline, six indole, and two isogranatanine alkaloids, were isolated from the stem-bark extract of the Malayan Leuconotis eugeniifolia. The structures and absolute configurations of these alkaloids were established based on the analysis of the spectroscopic data, GIAO NMR calculations, DP4+ probability analysis, TDDFT-ECD method, and X-ray diffraction analysis. Eugeniinaline A (1) represents a new pentacyclic quinoline alkaloid with a 6/6/5/6/7 ring system. Eugeniinaline G (7) and its seco-derivative, eugeniinaline H (8), were the first isogranatanine alkaloids isolated as natural products. The known alkaloids leucolusine (10) and melokhanine A (11) were found to be the same compound, based on comparison of the spectroscopic data of both compounds, with the absolute configuration of (7R, 20R, 21S). Eugeniinalines A and G (1 and 7) showed cytotoxic activity against the HT-29 cancer cell line with IC50 values of 7.1 and 7.2 µM, respectively.


Assuntos
Alcaloides , Antineoplásicos , Apocynaceae , Quinolinas , Humanos , Alcaloides/farmacologia , Apocynaceae/química , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Quinolinas/farmacologia , Alcaloides de Triptamina e Secologanina/química , Alcaloides de Triptamina e Secologanina/farmacologia
5.
Bioorg Chem ; 146: 107256, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460334

RESUMO

A new series of indolenines decorated with pyrazolo[3,4-b]pyridines were designed and synthesized in up to 96% yield from the acid-catalyzed cyclocondensation of 1,3-dialdehydes with 3-aminopyrazoles. X-ray crystallography on a representative derivative, 5n, revealed two close to planar conformations whereby the N-atom of the pyridyl residue was syn or anti to the pyrrole-N atom in the two independent molecules of the asymmetric unit. The computational and DNA binding data suggest that 5n is a strong DNA intercalator with the results in agreement with its potent cytotoxicity against two colorectal cancer cell lines (HCT 116 and HT-29). In contrast to doxorubicin, compounds 5k-o have higher druggability (compliance to more criteria stated in Lipinski's rule of five and Veber's rule), higher bioavailability, and better medicinal chemistry properties, indicative of their potential application as chemotherapeutical agents.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , DNA , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Piridinas/farmacologia , Piridinas/química , Relação Estrutura-Atividade , Pirazóis/química , Pirazóis/farmacologia , Indóis/química , Indóis/farmacologia
6.
J Asian Nat Prod Res ; 26(1): 78-90, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38069835

RESUMO

Phytochemical investigation on the aerial parts of Salvia deserta led to the isolation of eight new pentacyclic triterpenoids including three oleanane- (1 - 3) and five ursane-type (4 - 8) triterpenoids, whose structures were elucidated based on extensive spectroscopic analysis and quantum chemical calculation. Weak immunosuppressive potency was observed for compounds 1, 2, and 4 - 8 via inhibiting the secretion of cytokines TNF-α and IL-6 in LPS-induced macrophages RAW264.7 at 20 µM. In addition, compounds 1, 2, and 4 - 6 exhibited moderate protective activity on t-BHP-induced oxidative injury in HepG2 cells.


Assuntos
Salvia , Triterpenos , Triterpenos/farmacologia , Triterpenos/química , Salvia/química , Estrutura Molecular , Citocinas , Componentes Aéreos da Planta/química
7.
Mol Divers ; 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37278911

RESUMO

Five new compounds of benz[e]indole pyrazolyl-substituted amides (2a-e) were synthesised in low to good yields via the direct amide-coupling reaction between a pyrazolyl derivative containing a carboxylic acid and several amine substrates. The molecular structures were determined by various spectroscopic methods, such as NMR (1H, 13C and 19F), FT-IR and high-resolution mass spectrometry (HRMS). X-ray crystallographic analysis on the 4-fluorobenzyl derivative (2d) reveals the amide-O atom to reside to the opposite side of the molecule to the pyrazolyl-N and pyrrolyl-N atoms; in the molecular packing, helical chains feature amide-N‒H⋯N(pyrrolyl) hydrogen bonds. Density-functional theory (DFT) at the geometry-optimisation B3LYP/6-31G(d) level on the full series shows general agreement with the experimental structures. While the LUMO in each case is spread over the benz[e]indole pyrazolyl moiety, the HOMO spreads over the halogenated benzo-substituted amide moieties or is localised near the benz[e]indole pyrazolyl moieties. The MTT assay showed that 2e, exhibited the highest toxicity against a human colorectal carcinoma (HCT 116 cell line) without appreciable toxicity towards the normal human colon fibroblast (CCD-18Co cell line). Based on molecular docking calculations, the probable cytotoxic mechanism of 2e is through the DNA minor groove binding.

8.
Proc Natl Acad Sci U S A ; 117(25): 14386-14394, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513693

RESUMO

We report that two widely-used drugs for erectile dysfunction, tadalafil and vardenafil, trigger bone gain in mice through a combination of anabolic and antiresorptive actions on the skeleton. Both drugs were found to enhance osteoblastic bone formation in vivo using a unique gene footprint and to inhibit osteoclast formation. The target enzyme, phosphodiesterase 5A (PDE5A), was found to be expressed in mouse and human bone as well as in specific brain regions, namely the locus coeruleus, raphe pallidus, and paraventricular nucleus of the hypothalamus. Localization of PDE5A in sympathetic neurons was confirmed by coimmunolabeling with dopamine ß-hydroxylase, as well as by retrograde bone-brain tracing using a sympathetic nerve-specific pseudorabies virus, PRV152. Both drugs elicited an antianabolic sympathetic imprint in osteoblasts, but with net bone gain. Unlike in humans, in whom vardenafil is more potent than tadalafil, the relative potencies were reversed with respect to their osteoprotective actions in mice. Structural modeling revealed a higher binding energy of tadalafil to mouse PDE5A compared with vardenafil, due to steric clashes of vardenafil with a single methionine residue at position 806 in mouse PDE5A. Collectively, our findings suggest that a balance between peripheral and central actions of PDE5A inhibitors on bone formation together with their antiresorptive actions specify the osteoprotective action of PDE5A blockade.


Assuntos
Disfunção Erétil/tratamento farmacológico , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Inibidores da Fosfodiesterase 5/farmacologia , Envelhecimento/fisiologia , Animais , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Diferenciação Celular/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/química , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Reposicionamento de Medicamentos , Disfunção Erétil/complicações , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Modelos Animais , Modelos Moleculares , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/fisiologia , Osteoporose/complicações , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle , Inibidores da Fosfodiesterase 5/química , Inibidores da Fosfodiesterase 5/uso terapêutico , Cultura Primária de Células , Tadalafila/química , Tadalafila/farmacologia , Tadalafila/uso terapêutico , Dicloridrato de Vardenafila/química , Dicloridrato de Vardenafila/farmacologia , Dicloridrato de Vardenafila/uso terapêutico
9.
Proc Natl Acad Sci U S A ; 117(46): 28971-28979, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33127753

RESUMO

Blocking the action of FSH genetically or pharmacologically in mice reduces body fat, lowers serum cholesterol, and increases bone mass, making an anti-FSH agent a potential therapeutic for three global epidemics: obesity, osteoporosis, and hypercholesterolemia. Here, we report the generation, structure, and function of a first-in-class, fully humanized, epitope-specific FSH blocking antibody with a KD of 7 nM. Protein thermal shift, molecular dynamics, and fine mapping of the FSH-FSH receptor interface confirm stable binding of the Fab domain to two of five receptor-interacting residues of the FSHß subunit, which is sufficient to block its interaction with the FSH receptor. In doing so, the humanized antibody profoundly inhibited FSH action in cell-based assays, a prelude to further preclinical and clinical testing.


Assuntos
Tecido Adiposo/metabolismo , Anticorpos Bloqueadores/imunologia , Osso e Ossos/metabolismo , Epitopos , Hormônio Foliculoestimulante/imunologia , Animais , Anticorpos Bloqueadores/química , Anticorpos Monoclonais , Densidade Óssea , Feminino , Hormônio Foliculoestimulante/química , Subunidade beta do Hormônio Folículoestimulante/imunologia , Humanos , Hipercolesterolemia , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Dinâmica Molecular , Obesidade , Osteoporose , Receptores do FSH/metabolismo
10.
J Arthroplasty ; 38(9): 1705-1713.e1, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36940758

RESUMO

BACKGROUND: Although self-reported measures of physical disability are strong indication criterion for total knee arthroplasty (TKA) in painful knee osteoarthritis (OA), some patients may report greater-than-observed disability. Contributing factors to this discordance are relatively unexplored. We aimed to examine whether pain and negative affect, including anxiety and depression, were associated with the discordance of self-reported measures with performance-based measures (PPM) of physical function. METHODS: We used cross-sectional data (n = 212) from two randomized rehabilitation trials in knee OA. All patients were assessed for knee pain intensity and symptoms of anxiety and depression. Self-reported function was assessed by the Western Ontario and McMaster Universities Arthritis Index (WOMAC) physical-function subscale. Objective performance-based measures (PPMs) of physical function were assessed by timed gait and stair tests. Continuous discordance scores were quantified by the difference in percentiles between WOMAC and PPMs (WOMAC-PPM), where a positive discordance, WOMAC-PPM >0, implied greater perceived than observed disability. RESULTS: Around 1 in 4 patients had >20 percentile units in WOMAC-PPM discordance. In Bayesian regression analyses, knee pain intensity had >99% posterior probability of positive associations with WOMAC-PPM discordance. Among patients awaiting TKA, anxiety intensity had approximately 99% probability of positive associations with discordance, and these associations had >65% probability of exceeding 10 percentile units. In contrast, depression had low (79% to 88%) probability of any association with discordance. CONCLUSION: In patients who have knee OA, a sizable proportion reported substantially greater physical disability than actually observed. Pain and anxiety intensity, but not depression, were meaningful predictors of this discordance. If validated, our findings may help in refining patient selection criteria for TKA.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/cirurgia , Autorrelato , Medição da Dor , Estudos Transversais , Teorema de Bayes , Dor/complicações , Afeto
11.
Sensors (Basel) ; 23(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37420722

RESUMO

Hand gesture recognition (HGR) is a crucial area of research that enhances communication by overcoming language barriers and facilitating human-computer interaction. Although previous works in HGR have employed deep neural networks, they fail to encode the orientation and position of the hand in the image. To address this issue, this paper proposes HGR-ViT, a Vision Transformer (ViT) model with an attention mechanism for hand gesture recognition. Given a hand gesture image, it is first split into fixed size patches. Positional embedding is added to these embeddings to form learnable vectors that capture the positional information of the hand patches. The resulting sequence of vectors are then served as the input to a standard Transformer encoder to obtain the hand gesture representation. A multilayer perceptron head is added to the output of the encoder to classify the hand gesture to the correct class. The proposed HGR-ViT obtains an accuracy of 99.98%, 99.36% and 99.85% for the American Sign Language (ASL) dataset, ASL with Digits dataset, and National University of Singapore (NUS) hand gesture dataset, respectively.


Assuntos
Gestos , Reconhecimento Automatizado de Padrão , Humanos , Reconhecimento Automatizado de Padrão/métodos , Redes Neurais de Computação , Extremidade Superior , Língua de Sinais , Mãos
12.
Environ Microbiol ; 24(3): 1308-1325, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34708512

RESUMO

Terpios hoshinota is an aggressive, space-competing sponge that kills various stony corals. Outbreaks of this species have led to intense damage to coral reefs in many locations. Here, the first large-scale 16S rRNA gene survey across three oceans revealed that bacteria related to the taxa Prochloron, Endozoicomonas, SAR116, Ruegeria, and unclassified Proteobacteria were prevalent in T. hoshinota. A Prochloron-related bacterium was the most dominant and prevalent cyanobacterium in T. hoshinota. The complete genome of this uncultivated cyanobacterium and pigment analysis demonstrated that it has phycobiliproteins and lacks chlorophyll b, which is inconsistent with the definition of Prochloron. Furthermore, the cyanobacterium was phylogenetically distinct from Prochloron, strongly suggesting that it should be a sister taxon to Prochloron. Therefore, we proposed this symbiotic cyanobacterium as a novel species under the new genus Candidatus Paraprochloron terpiosi. Comparative genomic analyses revealed that 'Paraprochloron' and Prochloron exhibit distinct genomic features and DNA replication machinery. We also characterized the metabolic potentials of 'Paraprochloron terpiosi' in carbon and nitrogen cycling and propose a model for interactions between it and T. hoshinota. This study builds a foundation for the study of the T. hoshinota microbiome and paves the way for better understanding of ecosystems involving this coral-killing sponge.


Assuntos
Antozoários , Cianobactérias , Microbiota , Poríferos , Animais , Antozoários/microbiologia , Recifes de Corais , Cianobactérias/metabolismo , Poríferos/genética , Prevalência , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Simbiose
13.
Nature ; 536(7617): 460-3, 2016 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-27533035

RESUMO

Thermally activated ion channels are known to detect the entire thermal range from extreme heat (TRPV2), painful heat (TRPV1, TRPM3 and ANO1), non-painful warmth (TRPV3 and TRPV4) and non-painful coolness (TRPM8) through to painful cold (TRPA1). Genetic deletion of each of these ion channels, however, has only modest effects on thermal behaviour in mice, with the exception of TRPM8, the deletion of which has marked effects on the perception of moderate coolness in the range 10-25 °C. The molecular mechanism responsible for detecting non-painful warmth, in particular, is unresolved. Here we used calcium imaging to identify a population of thermally sensitive somatosensory neurons which do not express any of the known thermally activated TRP channels. We then used a combination of calcium imaging, electrophysiology and RNA sequencing to show that the ion channel generating heat sensitivity in these neurons is TRPM2. Autonomic neurons, usually thought of as exclusively motor, also express TRPM2 and respond directly to heat. Mice in which TRPM2 had been genetically deleted showed a striking deficit in their sensation of non-noxious warm temperatures, consistent with the idea that TRPM2 initiates a 'warm' signal which drives cool-seeking behaviour.


Assuntos
Temperatura Alta , Canais de Cátion TRPM/metabolismo , Animais , Aprendizagem da Esquiva , Cálcio/análise , Cálcio/metabolismo , Sinalização do Cálcio , Eletrofisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Análise de Sequência de RNA , Canais de Cátion TRPM/deficiência , Canais de Cátion TRPM/genética
14.
Environ Res ; 215(Pt 2): 114395, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36150443

RESUMO

Type 2 diabetes (T2DM) as a non-communicable disease imposes heavy disease burdens on society. Limited studies have been conducted to assess the effects of short-term air pollution exposure on T2DM, especially in Asian regions. Our research aimed to determine the association between short-term exposure to ambient nitrogen dioxide (NO2) and outpatient visits for T2DM in Chongqing, the largest city in western China, based on the data collected from November 28, 2013 to December 31, 2019. A generalized additive model (GAM) was applied, and stratified analyses were performed to investigate the potential modifying effects by age, gender, and season. Meanwhile, the disease burden was revealed from attributable risk. Positive associations between short-term NO2 and daily T2DM outpatient visits were observed. The strongest association was observed at lag 04, with per 10 µg/m3 increase of NO2 corresponded to increased T2DM outpatient visits at 1.57% [95% confidence interval (CI): 0.48%, 2.65%]. Stronger associations were presented in middle-aged group (35-64 years old), male group, and cool seasons (October to March). Moreover, there were 1.553% (8664.535 cases) of T2DM outpatient visits attributable to NO2. Middle-aged adults, males, and patients who visited in cool seasons suffered heavier burdens. Conclusively, short-term exposure to NO2 was associated with increased outpatient visits for T2DM. Attention should be paid to the impact of NO2 on the burden of T2DM, especially for those vulnerable groups.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Diabetes Mellitus Tipo 2 , Adulto , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , China/epidemiologia , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/epidemiologia , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/toxicidade , Pacientes Ambulatoriais , Material Particulado/análise , Material Particulado/toxicidade
15.
Planta Med ; 88(14): 1325-1340, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35100653

RESUMO

Two iboga-vobasine bisindoles, 16'-decarbomethoxyvoacamine (1: ) and its 19,20-dihydro derivative, 16'-decarbomethoxydihydrovoacamine (2: ) from Tabernaemontana corymbosa exhibited potent cytotoxicity against the human colorectal adenocarcinoma HT-29 cells in our previous studies. Bisindoles 1: and 2: selectively inhibited the growth of HT-29 cells without significant cytotoxicity to normal human colon fibroblasts CCD-18Co. Treatment with bisindoles 1: and 2: suppressed the formation of HT-29 colonies via G0/G1 cell cycle arrest and induction of mitochondrial apoptosis. Owing to its higher antiproliferative activity, bisindole 2: was chosen for the subsequent studies. Bisindole 2: inhibited the formation of HT-29 spheroids (tumor-like cell aggregates) in 3D experiments in a dose-dependent manner, while an in vitro tubulin polymerization assay and molecular docking analysis showed that bisindole 2: is a microtubule-stabilizing agent which is predicted to bind at the ß-tubulin subunit at the taxol-binding site. The binding resulted in the generation of ROS, which consequently activated the oxidative stress-related cell cycle arrest and apoptotic pathways, viz., JNK/p38, p21Cip1/Chk1, and p21Cip1/Rb/E2F, as shown by microarray profiling.


Assuntos
Adenocarcinoma , Antineoplásicos Fitogênicos , Neoplasias Colorretais , Ibogaína , Tabernaemontana , Humanos , Tabernaemontana/química , Células HT29 , Simulação de Acoplamento Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos Fitogênicos/farmacologia , Estrutura Molecular , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/química , Ibogaína/farmacologia , Apoptose , Neoplasias Colorretais/tratamento farmacológico , Microtúbulos , Linhagem Celular Tumoral
16.
Proc Natl Acad Sci U S A ; 116(52): 26808-26815, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31843930

RESUMO

The primitive neurohypophyseal nonapeptide oxytocin (OXT) has established functions in parturition, lactation, appetite, and social behavior. We have shown that OXT has direct actions on the mammalian skeleton, stimulating bone formation by osteoblasts and modulating the genesis and function of bone-resorbing osteoclasts. We deleted OXT receptors (OXTRs) selectively in osteoblasts and osteoclasts using Col2.3Cre and Acp5Cre mice, respectively. Both male and female Col2.3Cre+:Oxtrfl/fl mice recapitulate the low-bone mass phenotype of Oxtr+/- mice, suggesting that OXT has a prominent osteoblastic action in vivo. Furthermore, abolishment of the anabolic effect of estrogen in Col2.3Cre+:Oxtrfl/fl mice suggests that osteoblastic OXTRs are necessary for estrogen action. In addition, the high bone mass in Acp5Cre+:Oxtrfl/fl mice indicates a prominent action of OXT in stimulating osteoclastogenesis. In contrast, we found that in pregnant and lactating Col2.3Cre+:Oxtrfl/fl mice, elevated OXT inhibits bone resorption and rescues the bone loss otherwise noted during pregnancy and lactation. However, OXT does not contribute to ovariectomy-induced bone loss. Finally, we show that OXT acts directly on OXTRs on adipocytes to suppress the white-to-beige transition gene program. Despite this direct antibeiging action, injected OXT reduces total body fat, likely through an action on OXT-ergic neurons. Consistent with an antiobesity action of OXT, Oxt-/- and Oxtr-/- mice display increased total body fat. Overall, the actions of OXT on bone mass and body composition provide the framework for future therapies for osteoporosis and obesity.

17.
J Nat Prod ; 84(5): 1524-1533, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33872002

RESUMO

A new linearly fused macroline-sarpagine bisindole, angustilongine M (1), was isolated from the methanolic extract of Alstonia penangiana. The structure of the alkaloid was elucidated based on analysis of the spectroscopic data, and its biological activity was evaluated together with another previously reported macroline-akuammiline bisindole from the same plant, angustilongine A (2). Compounds 1 and 2 showed pronounced in vitro growth inhibitory activity against a wide panel of human cancer cell lines. In particular, the two compounds showed potent and selective antiproliferative activity against HT-29 cells, as well as strong growth inhibitory effects against HT-29 spheroids. Cell death mechanistic studies revealed that the compounds induced mitochondrial apoptosis and G0/G1 cell cycle arrest in HT-29 cells in a time-dependent manner, while in vitro tubulin polymerization assays and molecular docking analysis showed that the compounds are microtubule-stabilizing agents, which are predicted to bind at the ß-tubulin subunit at the Taxol-binding site.


Assuntos
Alstonia/química , Antineoplásicos Fitogênicos/farmacologia , Alcaloides Indólicos/farmacologia , Oxindóis/farmacologia , Moduladores de Tubulina/farmacologia , Apoptose/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Células HT29 , Humanos , Mitocôndrias/efeitos dos fármacos , Simulação de Acoplamento Molecular , Estrutura Molecular
19.
Herz ; 46(Suppl 2): 243-252, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33084909

RESUMO

OBJECTIVE: The aim of this study was to evaluate the prognostic value of a novel scoring system, based on D­dimer, total cholesterol, high-sensitivity cardiac troponin T (hs-cTnT), and serum albumin levels, in patients with heart failure. METHODS: A total of 221 patients diagnosed with heart failure between May 2016 to January 2020 were enrolled in this retrospective study. The prognostic significance of the biomarkers D­dimer, total cholesterol, hs-cTnT, and serum albumin was determined with univariate and multivariate Cox proportional hazard models. A novel prognostic score based on these predictors was established. The Kaplan-Meier method and log-rank test were used to compare the adverse outcomes of patients in different risk groups. RESULT: Results from univariate and multivariate analyses showed that high D­dimer, low serum albumin, high hs-cTnT, and low total cholesterol levels were independent prognostic factors for adverse outcomes (D-dimer >0.63 mg/l, HR = 1.84, 95% CI = 1.16-2.94, p = 0.010; serum albumin >34 g/l, HR = 0.67, 95% CI = 0.45-0.99, p = 0.046; hs-cTnT >24.06 pg/ml, HR = 1.65, 95% CI = 1.08-2.53, p = 0.020; total cholesterol >3.68 mmol/l, HR = 0.63, 95% CI = 0.43-0.92, p = 0.017). Moreover, all the patients were stratified into low-risk or high-risk group according to a scoring system based on these four markers. Kaplan-Meier analyses demonstrated that patients in the high-risk group were more prone to having adverse outcomes compared with patients in the low-risk group. CONCLUSION: D­dimer, total cholesterol, hs-cTnT, and serum albumin levels were independent prognostic factors in the setting of heart failure. A novel and comprehensive scoring system based on these biomarkers is an easily available and effective tool for predicting the adverse outcomes of patients with heart failure.


Assuntos
Insuficiência Cardíaca , Troponina T , Biomarcadores , Ácido Edético/análogos & derivados , Insuficiência Cardíaca/diagnóstico , Humanos , Prognóstico , Estudos Retrospectivos
20.
J Med Internet Res ; 23(4): e25094, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33847591

RESUMO

BACKGROUND: Blockchain technology has the potential to enable more secure, transparent, and equitable data management. In the health care domain, it has been applied most frequently to electronic health records. In addition to securely managing data, blockchain has significant advantages in distributing data access, control, and ownership to end users. Due to this attribute, among others, the use of blockchain to power personal health records (PHRs) is especially appealing. OBJECTIVE: This review aims to examine the current landscape, design choices, limitations, and future directions of blockchain-based PHRs. METHODS: Adopting the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines, a cross-disciplinary systematic review was performed in July 2020 on all eligible articles, including gray literature, from the following 8 databases: ACM, IEEE Xplore, MEDLINE, ScienceDirect, Scopus, SpringerLink, Web of Science, and Google Scholar. Three reviewers independently performed a full-text review and data abstraction using a standardized data collection form. RESULTS: A total of 58 articles met the inclusion criteria. In the review, we found that the blockchain PHR space has matured over the past 5 years, from purely conceptual ideas initially to an increasing trend of publications describing prototypes and even implementations. Although the eventual application of blockchain in PHRs is intended for the health care industry, the majority of the articles were found in engineering or computer science publications. Among the blockchain PHRs described, permissioned blockchains and off-chain storage were the most common design choices. Although 18 articles described a tethered blockchain PHR, all of them were at the conceptual stage. CONCLUSIONS: This review revealed that although research interest in blockchain PHRs is increasing and that the space is maturing, this technology is still largely in the conceptual stage. Being the first systematic review on blockchain PHRs, this review should serve as a basis for future reviews to track the development of the space.


Assuntos
Blockchain , Registros de Saúde Pessoal , Atenção à Saúde , Registros Eletrônicos de Saúde , Humanos , Tecnologia
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