Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
PLoS Pathog ; 20(2): e1011953, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38315719

RESUMO

Carbonic anhydrase IV (Car4) is a newly identified receptor that allows adeno-associated virus (AAV) 9P31 to cross the blood-brain barrier and achieve efficient infection in the central nervous system (CNS) in mouse models. However, the molecular mechanism by which engineered AAV capsids with 7-mer insertion in the variable region (VR) VIII recognize these novel cellular receptors is unknown. Here we report the cryo-EM structures of AAV9P31 and its complex with Mus musculus Car4 at atomic resolution by utilizing the block-based reconstruction (BBR) method. The structures demonstrated that Car4 binds to the protrusions at 3-fold axes of the capsid. The inserted 7-mer extends into a hydrophobic region near the catalytic center of Car4 to form stable interactions. Mutagenesis studies also identified the key residues in Car4 responsible for the AAV9P31 interaction. These findings provide new insights into the novel receptor recognition mechanism of AAV generated by directed evolution and highlight the application of the BBR method to studying the virus-receptor molecular mechanism.


Assuntos
Anidrase Carbônica IV , Dependovirus , Animais , Camundongos , Dependovirus/genética , Anidrase Carbônica IV/análise , Anidrase Carbônica IV/metabolismo , Capsídeo/metabolismo , Proteínas do Capsídeo/metabolismo , Barreira Hematoencefálica/metabolismo , Vetores Genéticos
2.
BMC Geriatr ; 24(1): 598, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997623

RESUMO

BACKGROUND: Both late-life depression and childhood maltreatment have become major global public health issues, given their prevalence and social-economic and health consequences. However, previous studies have solely focused on the relationship of childhood maltreatment to average levels of depressive symptoms. The current study addresses this gap of knowledge by simultaneously examining the impacts of childhood intra- and extra-familial maltreatment on age trajectories of depressive symptoms in later life in the Chinese context. METHODS: Hierarchical linear models were applied to data from the China Health and Retirement Longitudinal Study (2011-2018, N = 12,669 individuals aged 45 to 80, comprising N = 43,348 person-years). Depressive symptoms were measured by the CES-D-10 scale. Childhood intra-familial maltreatments were measured by physical abuse and emotional neglect, while extra-familial maltreatment was measured by peer bullying. All analyses were conducted separately by gender in Stata 16. RESULTS: Childhood extrafamilial peer bullying (ß = 1.628, p < 0.001), and intrafamilial physical abuse (ß = 0.746, p < 0.001) and emotional neglect (ß = 0.880, p < 0.001) were associated with higher later-life depressive symptoms levels in the whole sample. Peer bullying differences in depressive symptoms widened with age for both men and women. Physical abuse differences in depressive symptoms remained stable over the life course among men but increased among women. Emotional neglect differences in depressive symptoms decreased with age among men, while it increased first and then decreased among women. CONCLUSIONS: Findings in this study suggest that childhood maltreatment is not only associated with later-life poorer mental health but contributes to increasing inequalities in mental health as people age, especially among peer-bullying victims and women.


Assuntos
Depressão , Humanos , Masculino , Feminino , China/epidemiologia , Idoso , Estudos Longitudinais , Depressão/epidemiologia , Depressão/psicologia , Depressão/diagnóstico , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Maus-Tratos Infantis/psicologia , Bullying/psicologia
3.
Med Sci Monit ; 27: e927015, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33384404

RESUMO

BACKGROUND The aim of this study was to compare the efficacy and safety of oncoplastic breast-conserving therapy (OBCT) and SBCT (standard breast-conserving therapy) in breast cancer surgery. MATERIAL AND METHODS We enrolled 192 breast cancer patients who underwent breast-conserving surgery during January 2015 to April 2018. The surgery strategies of OBCT and SBCT were performed according to the patients' condition. For measurement of surgical cosmetic effects, the Harris scale, the modified objective scores, and the subjective evaluation were all used. The basic clinical characteristics, intraoperative indices, postoperative complications, metastasis, and recurrence during the 2-year follow-up were recorded. RESULTS The mean surgical time was remarkably longer and the resected volume was markedly larger in the OBCT group than in the SBCT group. The excellent and good ratios of Harris scale, the modified objective scores, and the ratio of very satisfied and satisfied patients by subjective scale were all significantly higher in the OBCT group than in the SBCT group. The occurrence rates of seroma and poor incision healing were remarkably lower in the OBCT group. No significant difference was found for metastasis and recurrence. CONCLUSIONS OBCT had better cosmetic effects, fewer complications, and no adverse effects on metastasis and recurrence.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Mastectomia Segmentar , Feminino , Seguimentos , Humanos , Cuidados Intraoperatórios , Estimativa de Kaplan-Meier , Mastectomia Segmentar/efeitos adversos , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/etiologia , Padrões de Referência , Cirurgia Plástica
4.
Exp Eye Res ; 201: 108271, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33007305

RESUMO

Previous studies have reported that endothelial-to-mesenchymal transition (EndoMT) contributes to pathological fibrosis in proliferative diabetic retinopathy (PDR). The hypothesis of our study was that exosomes from high glucose (HG)-treated ARPE19 cells reprogram endothelial cell behavior in HG conditions by transferring their genetic contents. Our study showed that ARPE19-derived exosomes were internalized by human umbilical vein endothelial cells (HUVECs). Additionally, miR-202-5p, a miRNA known to target TGFßR2, was enriched in ARPE19-derived exosomes. A dual luciferase reporter assay, qPCR, and western blotting were used to characterize the expression of miR-202-5p and phosphorylation of the TGF/Smad pathway proteins. We showed that miR-202-5p-containing exosomes suppressed HUVEC cell growth, migration, and tube formation. Furthermore, TGFßR2 was confirmed as the target of miR-202-5p. A dual luciferase reporter assay showed that TGFßR2 expression was negatively regulated by miR-202-5p. We also showed that miR-202-5p-containing exosomes suppressed HG-induced EndoMT. These collective results suggested that ARPE-derived exosomes may serve as significant mediators of cell-to-cell crosstalk to suppress EndoMT by transferring miR-202-5p through the TGF/Smad pathway, and may be a potential treatment for PDR patients.


Assuntos
Retinopatia Diabética/genética , Exossomos/genética , Regulação da Expressão Gênica , MicroRNAs/genética , RNA/genética , Epitélio Pigmentado da Retina/metabolismo , Apoptose , Western Blotting , Células Cultivadas , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Exossomos/metabolismo , Exossomos/ultraestrutura , Humanos , MicroRNAs/biossíntese , Microscopia Eletrônica de Transmissão , Epitélio Pigmentado da Retina/patologia
5.
Anticancer Drugs ; 31(10): 997-1003, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33065690

RESUMO

Lung cancer always ranks first in the number of cancer deaths every year, accounting for 18.4% of total cancer deaths in 2018. Metastasis is the main cause of death in lung cancer patients. The identification of bioactive components of traditional Chinese medicine is very important for the development of novel reagents against non-small cell lung cancer (NSCLC). Rosthorin A has originated from Rabdosia rosthornii (Diels) Hara which excerpts from 'Chinese materia medica', and is known to have 'clear heat phlegm' properties in the folk. Little is known about the biological functions and mechanisms of Rosthorin A in cancer cells at present. The role of EMT in metastasis of a tumor cell is self-evident. Slug is an important EMT inducer, which is related to the development of lung cancer. Cell growth, clone assay, cell migration, cell invasion, and protein expression, and NSCLC transplanted tumor growth were performed in A549, H1299, and H1975 cells. Rosthorin A significantly inhibited the growth of NSCLC cells, it could prolong the survival of nude mice. Rosthorin A inhibited the migration and invasion of A549, H1299, and H1975 cells. Rosthorin A up-regulated E-cadherin expression level and down-regulated the expression of ß-catenin, N-cadherin, vimentin, Slug, and Twist. Rosthorin A could promote the expression of E-cadherin and inhibit the development of EMT by downregulating Slug, to inhibit the development and metastasis of NSCLC cells. In summary, Rosthorin A could be used as a promising candidate for the treatment of NSCLC patients with recurrence and metastasis.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Polifenóis/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos BALB C , Proteínas Nucleares/metabolismo , Polifenóis/química , Fatores de Transcrição da Família Snail/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Vimentina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
6.
Int J Mol Sci ; 21(6)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183046

RESUMO

BACKGROUND: Diabetes mellitus is a growing global health issue nearly across the world. Diabetic patients who are prone to develop diabetes-related complications often exhibit progressive neuropathy (painless and sensory loss). It is usual for small wounds to progress to ulceration, which especially worsens with peripheral arterial disease and in the presence of anaerobic bacteria, culminating into gangrene. In our study, vaccarin (VAC), the main active monomer extracted from Chinese herb vaccariae semen, is proven to have a role in promoting diabetic chronic wound healing through a cytoprotective role under high glucose conditions. MATERIALS AND METHODS: We constructed a pressure ulcer on both VAC-treated and control mice based on a type 1 diabetes (T1DM) model. The wound healing index was evaluated by an experimental wound assessment tool (EWAT). We also determined the effect of VAC on the proliferation and cell migration of human microvascular endothelial cells (HMEC-1) by a cell counting kit (CCK-8), a scratch and transwell assay. RESULTS: The results demonstrated that VAC could promote the proliferation and migration of high glucose-stimulated HMEC-1 cells, which depend on the activation of FOXP2/AGGF1. Activation of the angiogenic factor with G patch and FHA domains 1 (AGGF1) caused enhanced phosphorylation of serine/threonine kinase (Akt) and extracellular regulated protein kinases (Erk1/2). By silencing the expression of forkhead box p2 (FOXP2) protein by siRNA, both mRNA and protein expression of AGGF1 were downregulated, leading to a decreased proliferation and migration of HMEC-1 cells. In addition, a diabetic chronic wound model in vivo unveiled that VAC had a positive effect on chronic wound healing, which involved the activation of the above-mentioned pathways. CONCLUSIONS: In summary, our study found that VAC promoted chronic wound healing in T1DM mice by activating the FOXP2/AGGF1 pathway, indicating that VAC may be a promising candidate for the treatment of the chronic wounds of diabetic patients.


Assuntos
Proteínas Angiogênicas/metabolismo , Diabetes Mellitus Experimental/complicações , Flavonoides/uso terapêutico , Fatores de Transcrição Forkhead/metabolismo , Glicosídeos/uso terapêutico , Úlcera por Pressão/tratamento farmacológico , Proteínas Repressoras/metabolismo , Cicatrização , Proteínas Angiogênicas/genética , Animais , Movimento Celular , Proliferação de Células , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/fisiologia , Endotélio Vascular/citologia , Flavonoides/farmacologia , Fatores de Transcrição Forkhead/genética , Glicosídeos/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Úlcera por Pressão/etiologia , Úlcera por Pressão/metabolismo , Proteínas Repressoras/genética
7.
Acta Pharmacol Sin ; 40(8): 1119-1126, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30760834

RESUMO

Successful prevention and treatment of hypertension depend on the appropriate combination of antihypertensive drug therapy and nondrug lifestyle modification. While most hypertension guidelines recommend moderate- to high-intensity exercise, we decided to explore a mild yet effective type of exercise to add to hypertension management, especially in populations with complications or frailty. After comparing the short-term cardiovascular effects of low-speed walking versus high-speed walking for 3 kilometers (km) (3 km/h versus 6 km/h) in young, healthy volunteers, we delivered low-speed walking (low-intensity walking, 2.5 metabolic equivalents of task, METs) as exercise therapy in 42 prehypertensive and 43 hypertensive subjects. We found that one session of 3 km low-intensity walking exerted a transient pressure-lowering effect as well as a mild negative chronotropic effect on heart rate in both the prehypertensive and hypertensive subjects; these short-term benefits on blood pressure and heart rate were accompanied by a brief increase in urine ß-endorphin output. Then we prescribed regular low-intensity walking with a target exercise dose (exercise volume) of 500-1000 METs·min/week (50-60 min/day and 5-7 times/week) in hypertensive subjects in addition to their daily activities. Regular low-intensity walking also showed mild but significant blood pressure-lowering and heart rate-reducing effects in 7 hypertensive subjects within two months. It is hypothesized that regular low-intensity exercise of the necessary dose could be taken as a pragmatic and supplementary medication for hypertension management.


Assuntos
Hipertensão/terapia , Pré-Hipertensão/terapia , Caminhada , Adulto , Idoso , Pressão Sanguínea/fisiologia , Terapia por Exercício/métodos , Feminino , Frequência Cardíaca/fisiologia , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pré-Hipertensão/fisiopatologia , beta-Endorfina/urina
8.
Sensors (Basel) ; 19(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682858

RESUMO

As a new type of micro-electro-mechanical systems (MEMS) inertial sensor, the Quartz Vibrating Beam Accelerometer (QVBA) is widely used in intelligent sweeping robots, small aircraft, navigation systems, etc. For these applications, correcting and compensating the attitude angle with the result of acceleration plays an important role to improve the measurement accuracy. The synchronization error between the measurement of the accelerometer and gyroscope attitude angle has an adverse impact on the accuracy of the attitude angle. In this paper, a synchronous acquisition scheme of the accelerometer and gyroscope attitude angle in a strapdown inertial navigation system (SINS) is proposed. At the same time, to improve the sampling accuracy and the conversion speed of QVBA, an improved equal-precision frequency measuring method is also implemented in this paper. The hardware float point unit (FPU) is used to accelerate the calculation of the frequency measurement value. The long-term cumulative error of the frequency measurement value is less than 10 - 4 . The calculation process time from sampling to attitude angle compensation calculation is reduced by 40.8%. This work has played a very good role in improving the measurement accuracy and speed of the SINS.

9.
Int J Mol Sci ; 20(18)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533227

RESUMO

Cardiovascular complications are a major leading cause of mortality in patients suffering from type 2 diabetes mellitus (T2DM). Vascular endothelial dysfunction is a core pathophysiological event in the early stage of T2DM and eventually leads to cardiovascular disease. Vaccarin (VAC), an active flavonoid glycoside extracted from vaccariae semen, exhibits extensive biological activities including vascular endothelial cell protection effects. However, little is known about whether VAC is involved in endothelial dysfunction regulation under high glucose (HG) or hyperglycemia conditions. Here, in an in vivo study, we found that VAC attenuated increased blood glucose, increased glucose and insulin tolerance, relieved the disorder of lipid metabolism and oxidative stress, and improved endothelium-dependent vasorelaxation in STZ/HFD-induced T2DM mice. Furthermore, in cultured human microvascular endothelial cell-1 (HMEC-1) cells, we showed that pretreatment with VAC dose-dependently increased nitric oxide (NO) generation and the phosphorylation of eNOS under HG conditions. Mechanistically, VAC-treated HMEC-1 cells exhibited higher AMPK phosphorylation, which was attenuated by HG stimulation. Moreover, HG-triggered miRNA-34a upregulation was inhibited by VAC pretreatment, which is in accordance with pretreatment with AMPK inhibitor compound C (CC). In addition, both reactive oxygen species (ROS) scavenger N-acetyl-L-cysteine (NAC) and VAC abolished HG-evoked dephosphorylation of AMPK and eNOS, increased miRNA-34a expression, and decreased NO production. These results suggest that VAC impedes HG-induced endothelial dysfunction via inhibition of the ROS/AMPK/miRNA-34a/eNOS signaling cascade.


Assuntos
Angiopatias Diabéticas/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Glicosídeos/farmacologia , Substâncias Protetoras/farmacologia , Animais , Diabetes Mellitus Tipo 2/metabolismo , Angiopatias Diabéticas/tratamento farmacológico , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/patologia , Modelos Animais de Doenças , Glicosídeos/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , MicroRNAs , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Substâncias Protetoras/química , Espécies Reativas de Oxigênio/metabolismo
10.
Molecules ; 24(22)2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703459

RESUMO

This study describes the chemical constituents of Albiziae Cortex and their ability to ameliorate steatosis and promote proliferation and anti-oxidation in vitro. Together, five known lignan glycosides, (7S,8R)-erythro-syringylglycerol-ß-O-4'-sinapyl ether 9-O-ß-D-glucopyranoside (1), (+)-lyoniresinol-9'-O-gluco-side (2), (-)-lyoniresinol-9'-O-glucoside (3), picraquassioside C (4), and icariside E5 (5), were isolated from the Albiziae Cortex. Their structures were elucidated by extensive NMR and high-resolution mass spectrometry analysis and compared with reported data. Oil Red O staining results revealed that compounds 1, 2, and 3 attenuated lipid accumulation and lipid metabolic disorders in FFAs (oleate/palmitate, 2:1 ratio, 0.3 mM)-exposed HepG2 cells. The Cell Counting Kit 8 (CCK-8) assay results revealed that compounds 1 and 5 can significantly promote human umbilical vein endothelial cell (HUVEC) proliferation; meanwhile, these compounds did not exhibit significant cytotoxicity against HUVECs. In addition, 2',7'-dichlorofluorescein diacetate (DCFH-DA) staining results revealed that high glucose (HG)-induced reactive oxygen species (ROS) production was abolished by compounds 1, 2, and 3. This is the first report of the isolation of lignan skeletons from the genus Albizzia julibrissin with the ability to ameliorate steatosis and promote proliferation and anti-oxidation activities.


Assuntos
Albizzia/química , Antioxidantes , Proliferação de Células/efeitos dos fármacos , Fígado Gorduroso/tratamento farmacológico , Lignanas/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular , Ácido Oleico/metabolismo , Oxirredução , Ácido Palmítico/metabolismo
11.
PLoS Genet ; 10(8): e1004545, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25121504

RESUMO

Transcriptional/translational feedback loops drive daily cycles of expression in clock genes and clock-controlled genes, which ultimately underlie many of the overt circadian rhythms manifested by organisms. Moreover, phosphorylation of clock proteins plays crucial roles in the temporal regulation of clock protein activity, stability and subcellular localization. dCLOCK (dCLK), the master transcription factor driving cyclical gene expression and the rate-limiting component in the Drosophila circadian clock, undergoes daily changes in phosphorylation. However, the physiological role of dCLK phosphorylation is not clear. Using a Drosophila tissue culture system, we identified multiple phosphorylation sites on dCLK. Expression of a mutated version of dCLK where all the mapped phospho-sites were switched to alanine (dCLK-15A) rescues the arrythmicity of Clk(out) flies, yet with an approximately 1.5 hr shorter period. The dCLK-15A protein attains substantially higher levels in flies compared to the control situation, and also appears to have enhanced transcriptional activity, consistent with the observed higher peak values and amplitudes in the mRNA rhythms of several core clock genes. Surprisingly, the clock-controlled daily activity rhythm in dCLK-15A expressing flies does not synchronize properly to daily temperature cycles, although there is no defect in aligning to light/dark cycles. Our findings suggest a novel role for clock protein phosphorylation in governing the relative strengths of entraining modalities by adjusting the dynamics of circadian gene expression.


Assuntos
Proteínas CLOCK/genética , Ritmo Circadiano/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Alanina/genética , Animais , Proteínas CLOCK/biossíntese , Proteínas de Drosophila/biossíntese , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Mutação , Fosforilação/genética , RNA Mensageiro/biossíntese
12.
J Biol Chem ; 289(28): 19681-93, 2014 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-24872414

RESUMO

Circadian (≅ 24 h) clocks control daily rhythms in metabolism, physiology, and behavior in animals, plants, and microbes. In Drosophila, these clocks keep circadian time via transcriptional feedback loops in which clock-cycle (CLK-CYC) initiates transcription of period (per) and timeless (tim), accumulating levels of PER and TIM proteins feed back to inhibit CLK-CYC, and degradation of PER and TIM allows CLK-CYC to initiate the next cycle of transcription. The timing of key events in this feedback loop are controlled by, or coincide with, rhythms in PER and CLK phosphorylation, where PER and CLK phosphorylation is high during transcriptional repression. PER phosphorylation at specific sites controls its subcellular localization, activity, and stability, but comparatively little is known about the identity and function of CLK phosphorylation sites. Here we identify eight CLK phosphorylation sites via mass spectrometry and determine how phosphorylation at these sites impacts behavioral and molecular rhythms by transgenic rescue of a new Clk null mutant. Eliminating phosphorylation at four of these sites accelerates the feedback loop to shorten the circadian period, whereas loss of CLK phosphorylation at serine 859 increases CLK activity, thereby increasing PER levels and accelerating transcriptional repression. These results demonstrate that CLK phosphorylation influences the circadian period by regulating CLK activity and progression through the feedback loop.


Assuntos
Proteínas CLOCK/metabolismo , Ritmo Circadiano/fisiologia , Proteínas de Drosophila/metabolismo , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Proteínas CLOCK/genética , Proteínas de Drosophila/genética , Drosophila melanogaster , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Fosforilação/fisiologia
13.
Int J Cancer ; 136(11): 2556-65, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25370454

RESUMO

Epidemiological, preclinical and cellular studies in the last 5 years have shown that metformin exerts anti-tumoral properties, but its mode of action in cancer remains unclear. Here, we investigated the effects of metformin on a mouse hepatocellular carcinoma (HCC) model and tumor-associated T cell immune responses. Oral metformin administration led to a significant reduction of tumor growth, which was accompanied by decreased interleukin-22 (IL-22). Meanwhile, IL-22-induced STAT3 phosphorylation and upregulation of downstream genes Bcl-2 and cyclin D1 were inhibited by metformin. At the cellular level, metformin attenuated Th1- and Th17-derived IL-22 production. Furthermore, metformin inhibited de novo generation of Th1 and Th17 cells from naive CD4(+) cells. These observations were further supported by the fact that metformin treatment inhibited CD3/CD28-induced IFN-γ and IL-17A expression along with the transcription factors that drive their expression (T-bet [Th1] and ROR-γt [Th17], respectively). The effects of metformin on T cell differentiation were mediated by downregulated STAT3 and STAT4 phosphorylation via the AMP-activated kinase-mammalian target of rapamycin complex 1 pathway. Notably, metformin led to a reduction in glucose transporter Glut1 expression, resulting in less glucose uptake, which is critical to regulate CD4(+) T cell fate. Taken together, these findings provide evidence for the growth-inhibitory and immune-modulatory effects of metformin in HCC and thus, broaden our understanding about the action of metformin in liver cancer treatment.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Interleucinas/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Metformina/administração & dosagem , Animais , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Transdução de Sinais/efeitos dos fármacos , Interleucina 22
15.
Zhonghua Bing Li Xue Za Zhi ; 43(7): 468-72, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25327797

RESUMO

OBJECTIVE: To evaluated HER2 status using immunohistochemistry (IHC) assay and fluorescence in situ hybridization (FISH) at two different time points of tissue fixation after surgical resection of gastric cancer, emphasizing the importance of standard operation and quality control in HER2 testing. METHODS: Forty-one resection specimens of advanced gastric cancer were collected with tissue fixation periods of < 30 min or > 30 min after surgical resection. HER2 status was evaluated by immunohistochemistry (IHC) assay and fluorescence in situ hybridization (FISH). RESULTS: The frequency of HER2 expression by IHC in the samples with fixation time of < 30 min was higher than that in those of > 30 min (P < 0.05). However, no significant difference was observed by FISH (P > 0.05) between the two groups. Samples of < 30 min fixation time had high concordant results between IHC and FISH (100.0% for both positive and negative cases, Rho = 0.724, P < 0.05). In addition, HER2 expression by IHC was significantly correlated with Lauren classification, histologic differentiation, TNM stage and gender (P < 0.05). CONCLUSION: The time to tissue fixation after surgical resection of more than 30 min has deleterious effect on the detection of HER2 by IHC although FISH testing is not affected.


Assuntos
Receptor ErbB-2/análise , Neoplasias Gástricas/química , Fixação de Tecidos/métodos , Idoso , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Fatores de Tempo
16.
Eur J Intern Med ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38871563

RESUMO

BACKGROUND: Previous studies have reported that rituximab (RTX) therapy might be beneficial in reducing relapse rates in patients with IgG4-related disease (IgG4-RD). Therefore, we aimed to systematically assess the efficacy and safety of RTX induction treatment and the effect of RTX maintenance in patients with IgG4-RD. METHODS: The protocol was registered in the PROSPERO (CRD42023427352). PubMed, Embase, the Cochrane database, Scopus, and the Web of Science were interrogated to identify studies that evaluated the impact of RTX on prognosis in IgG4-RD. We explored the impact of various subgroups of factors on relapse outcomes and focused on the possible role of maintenance therapy in reducing relapse rates. The pooled incidence of adverse events of RTX therapy and the influencing factors have also been evaluated. RESULTS: Eighteen studies comprising 374 patients (mean age 56.0 ± 8.7 years; male 73.7 %) with a mean follow-up duration of 23.4 ± 16.3 months were included. The pooled estimate of the response rate, complete remission rate, overall relapse rate, adverse event rate, and serious adverse event rate of RTX induction therapy were 97.3 % (95 % CI, 94.7 %-99.1 %), 55.8 % (95 % CI, 39.6 %-71.3 %), 16.9 % (95 % CI, 8.7 %-27.1 %), 31.6 % (95 % CI, 16.7 %-48.9 %) and 3.9 % (95 % CI, 0.8 %-8.9 %), respectively. In subgroup analysis, the pooled relapse rate was significantly lower in studies with maintenance than without maintenance (2.8% vs 21.5 %, p < 0.01). Pooled Kaplan-Meier relapse curves also demonstrated that RTX maintenance therapy provided a better prognosis. CONCLUSIONS: RTX induction therapy appears to have satisfactory efficacy in the induction of remission in IgG4-RD. In addition, prophylactic RTX maintenance therapy after induction may be beneficial in preventing relapse of IgG4-RD.

17.
Orphanet J Rare Dis ; 19(1): 40, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308282

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is an irreversible degenerative disease. Placebo-controlled randomized trials are currently the main trial design to assess the clinical efficacy of drugs for ALS treatment. The aim of this study was to establish models to quantitatively describe the course of ALS, explore influencing factors, and provide the necessary information for ALS drug development. METHODS: We conducted a comprehensive search of PubMed and the Cochrane Library Central Register for placebo-controlled trials that evaluated treatments for ALS. From these trials, we extracted the clinical and demographic characteristics of participants in the placebo group, as well as outcome data, which encompassed overall survival (OS) and Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) scores, at various time points. RESULTS: In total, 47 studies involving 6118 participants were included. Disease duration and the proportion of patients receiving riluzole were identified as significant factors influencing OS in the placebo group. Specifically, the median OS was 35.5 months for a disease duration of 9 months, whereas it was 20.0 months for a disease duration of 36 months. Furthermore, for every 10% increase in the proportion of patients treated with riluzole (100 mg daily), there was an association with a median OS extension of approximately 0.4 months. The estimated time for the ALSFRS-R score in the placebo group to decrease to 50% of its maximum effect from baseline level was approximately 17.5 months, and the time to reach a plateau was about 40 months. CONCLUSIONS: The established disease course model of the historical placebo group is valuable in the decision-making process for the clinical development of ALS drugs. It serves not only as an external control to evaluate the efficacy of the tested drug in single-arm trials but also as prior information that aids in accurately estimating the posterior distribution of the disease course in the placebo group during small-sample clinical trials.

18.
Cancer Lett ; 598: 217093, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38969160

RESUMO

Histones are the main components of chromatin, functioning as an instructive scaffold to maintain chromosome structure and regulate gene expression. The dysregulation of histone modification is associated with various pathological processes, especially cancer initiation and development, and histone methylation plays a critical role. However, the specific mechanisms and potential therapeutic targets of histone methylation in cancer are not elucidated. Lys-specific demethylase 1A (LSD1) was the first identified demethylase that specifically removes methyl groups from histone 3 at lysine 4 or lysine 9, acting as a repressor or activator of gene expression. Recent studies have shown that LSD1 promotes cancer progression in multiple epigenetic regulation or non-epigenetic manners. Notably, LSD1 dysfunction is correlated with repressive cancer immunity. Many LSD1 inhibitors have been developed and clinical trials are exploring their efficacy in monotherapy, or combined with other therapies. In this review, we summarize the oncogenic mechanisms of LSD1 and the current applications of LSD1 inhibitors. We highlight that LSD1 is a promising target for cancer treatment. This review will provide the latest theoretical references for further understanding the research progress of oncology and epigenetics, deepening the updated appreciation of epigenetics in cancer.

19.
Eur J Cancer Prev ; 33(2): 105-114, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38299664

RESUMO

OBJECTIVES: Adjuvant chemotherapy benefits in elderly patients with stage II colon cancer (CC) remain controversial. We aimed to construct a nomogram to estimate the chemotherapy survival benefits in elderly patients. METHODS: The training and testing cohort were patients with stage II CC older than 70 years from the Surveillance, Epidemiology, and End Results (SEER) database, while the external validation cohort included patients from the National Cancer Center (NCC). Cox proportional hazard models were used to determine the covariates associated with overall survival (OS). Using the risk factors identified by Cox proportional hazards regression, a nomogram was developed to predict OS. Nomogram precision was assessed using receiver operating characteristic and calibration curves. RESULTS: The present study recruited 42 097 and 504 patients from the SEER database and NCC, respectively. The OS of patients who underwent surgery plus adjuvant chemotherapy was considerably longer than patients who underwent surgery alone. The nomogram included variables related to OS, including age, year of diagnosis, sex, AJCC T stage, tumor location, tumor size, harvested lymph nodes, and chemotherapy. According to the nomogram score, the elderly patients were separated into high- and low-risk groups, with high-risk group nomogram scores being greater than the median value, and vice versa. Patients in the high-risk group witnessed worse prognosis and were more likely to benefit from postoperative chemotherapy. CONCLUSION: This nomogram can be regarded as a useful clinical tool for assessing the potential adjuvant chemotherapy benefits and for predicting survival in elderly patients with stage II CC.


Assuntos
Neoplasias do Colo , Nomogramas , Idoso , Humanos , Prognóstico , Quimioterapia Adjuvante , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/epidemiologia , Bases de Dados Factuais
20.
Hum Mol Genet ; 20(15): 3022-30, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21551454

RESUMO

Berardinelli-Seip congenital lipodystrophy type 2 (BSCL2) is an autosomal recessive disorder characterized by an almost complete loss of adipose tissue, insulin resistance and fatty liver. Here, we create the first murine model of BSCL2 by targeted disruption of seipin, the causative gene for BSCL2. Compared with their wild-type littermates, the seipin(-/-) mice are viable and of normal weight but display significantly reduced adipose tissue mass, hepatic steatosis, glucose intolerance and hyperinsulinemia. The levels of leptin and adiponectin were both significantly decreased in seipin(-/-) mice, so were non-esterified fatty acids upon fasting. Surprisingly, however, hypertriglyceridemia which is common in human BSCL, was not observed in seipin(-/-) mice. Our findings suggest a possible tissue-autonomous role of seipin in liver lipid storage. The availability of the seipin(-/-) mice should help elucidate the molecular function of seipin and lead to a better understanding of the many metabolic consequences of human BSCL2.


Assuntos
Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Lipodistrofia Generalizada Congênita/metabolismo , Adiponectina/genética , Adiponectina/metabolismo , Tecido Adiposo/metabolismo , Animais , Peso Corporal/genética , Peso Corporal/fisiologia , Subunidades gama da Proteína de Ligação ao GTP/genética , Genótipo , Humanos , Leptina/genética , Leptina/metabolismo , Lipodistrofia Generalizada Congênita/genética , Imageamento por Ressonância Magnética , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA