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1.
BMC Med ; 22(1): 133, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38520024

RESUMO

BACKGROUND: Sarcopenic obesity, a clinical and functional condition characterized by the coexistence of obesity and sarcopenia, has not been investigated in relation to dementia risk and its onset. METHODS: We included 208,867 participants from UK biobank, who aged 60 to 69 years at baseline. Dementia diagnoses were identified using hospital records and death register data. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models to evaluate the associations of obesity, sarcopenia, and sarcopenic obesity with dementia risk, stratified by sex. Stratified analyses were performed across dementia-related polygenic risk score (PRS). Restricted mean survival time models were established to estimate the difference and 95%CIs of dementia onset across different status. Additionally, linear regression models were employed to estimate associations of different status with brain imaging parameters. The mediation effects of chronic diseases were also examined. RESULTS: Obese women with high PRS had a decreased risk (HR = 0.855 [0.761-0.961]), but obese men with low PRS had an increased risk (HR = 1.223 [1.045-1.431]). Additionally, sarcopenia was associated with elevated dementia risk (HRwomen = 1.323 [1.064-1.644]; HRmen = 2.144 [1.753-2.621]) in those with low PRS. Among those with high PRS, however, the association was only significant in early-life (HRwomen = 1.679 [1.355-2.081]; HRmen = 2.069 [1.656-2.585]). Of note, sarcopenic obesity was associated with higher dementia risk (HRwomen = 1.424 [1.227-1.653]; HRmen = 1.989 [1.702-2.323]), and results remained similar stratified by PRS. Considering dementia onset, obesity was associated with dementia by 1.114 years delayed in women, however, 0.170 years advanced in men. Sarcopenia (women: 0.080 years; men: 0.192 years) and sarcopenic obesity (women: 0.109 years; men: 0.511 years) respectively advanced dementia onset. Obesity, sarcopenia, and sarcopenic obesity were respectively related to alterations in different brain regions. Association between sarcopenic obesity and dementia was mediated by chronic diseases. CONCLUSIONS: Sarcopenic obesity and sarcopenia were respectively associated with increased dementia risk and advanced dementia onset to vary degree. The role of obesity in dementia may differ by sex and genetic background.


Assuntos
Demência , Sarcopenia , Masculino , Humanos , Feminino , Sarcopenia/complicações , Sarcopenia/epidemiologia , Estudos de Coortes , Paradoxo da Obesidade , Obesidade/complicações , Obesidade/epidemiologia , Estratificação de Risco Genético , Doença Crônica , Demência/etiologia , Demência/complicações
2.
MMWR Morb Mortal Wkly Rep ; 73(43): 958-964, 2024 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-39480696

RESUMO

Pregnancy is associated with increased risk for severe illness and complications associated with influenza infection. Insufficient knowledge about the risk for influenza among pregnant women and their health care providers in China is an important barrier to increasing influenza vaccination coverage and treating influenza and its complications among pregnant women. Improved influenza incidence estimates might promote wider vaccine acceptance and higher vaccination coverage. In Suzhou, active population-based surveillance during October 2018-September 2023 estimated that the annual rate of hospitalization for acute respiratory or febrile illness (ARFI) among women who were pregnant or <2 weeks postpartum was 11.1 per 1,000 live births; the annual rate of laboratory-confirmed influenza-associated ARFI (influenza ARFI) hospitalization in this group was 2.1 per 1,000 live births. A majority of hospitalized pregnant or early postpartum patients with ARFI (82.6%; 2,588 of 3,133) or influenza ARFI (85.5%; 423 of 495) were admitted to obstetrics wards rather than respiratory medicine wards. Only one (0.03%) pregnant or postpartum ARFI patient had received influenza vaccination, and 31.3% of pregnant or postpartum women hospitalized for influenza ARFI received antiviral treatment; the lowest percentage of hospitalized women with influenza ARFI who received antiviral treatment was among women admitted to obstetrics and gynecology wards (29.6% and 23.1%, respectively), compared with 54.1% of those admitted to a respiratory medicine ward. These findings highlight the risk for influenza and its associated complications among pregnant and postpartum women, the low rates of influenza vaccination among pregnant women, and of antiviral treatment of women with ARFI admitted to obstetrics and gynecology wards. Increasing awareness of the prevalence of influenza ARFI among pregnant women, the use of empiric antiviral treatment for ARFI, and the infection control in obstetrics wards during influenza seasons might help reduce influenza-associated morbidity among pregnant and postpartum women.


Assuntos
Hospitalização , Influenza Humana , Complicações Infecciosas na Gravidez , Humanos , Feminino , Gravidez , Influenza Humana/epidemiologia , China/epidemiologia , Hospitalização/estatística & dados numéricos , Adulto , Complicações Infecciosas na Gravidez/epidemiologia , Adulto Jovem , Período Pós-Parto , Vacinas contra Influenza/administração & dosagem , Adolescente
3.
Ecotoxicol Environ Saf ; 282: 116687, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38981395

RESUMO

The changing climate poses a growing challenge to the population health. The objective of this study was to assess the association between ambient temperature and cause-specific mortality in Suzhou. Based on the non-accidental mortality data collected during 2008-2022 in Suzhou, China, this study utilized an individual-level case-crossover design to evaluate the associations of temperature with cause-specific mortality. We applied a distributed lag nonlinear model with a maximum lag of 14 days to account for lag effects. Mortality risk due to extreme cold (<2.5th percentile) and extreme heat (>97.5th percentile) was analyzed. A total of 634,530 non-accidental deaths were analyzed in this study. An inverse J-shaped exposure-response relationship was observed between ambient temperature and non-accidental mortality, with the minimum mortality temperature (MMT) at 29.1℃. The relative risk (RR) of mortality associated with extreme cold (2.5th percentile) was 1.37 [95 % confidence interval (CI): 1.30, 1.44], higher than estimate of 1.09 (95 %CI: 1.07, 1.11) for extreme heat (97.5th percentile) relative to the MMT. Heat effect lasted for 2-3 days, while cold effect could persist for almost 14 days. Higher mortality risk estimates were observed for cardiorespiratory deaths compared to total deaths, with statistically significant between-group differences. Consequently, this study provides first-hand evidence on the associations between ambient temperatures and mortality risks from various causes, which could help local government and policy-makers in designing targeted strategies and public health measures against the menace of climate change.


Assuntos
Estudos Cross-Over , China/epidemiologia , Humanos , Feminino , Masculino , Mortalidade/tendências , Pessoa de Meia-Idade , Mudança Climática , Adulto , Temperatura , Exposição Ambiental/estatística & dados numéricos , Exposição Ambiental/efeitos adversos , Idoso , Causas de Morte , Adulto Jovem , Calor Extremo/efeitos adversos
4.
Environ Toxicol ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39415627

RESUMO

Glycine decarboxylase (GLDC) has been identified to be dysregulated and plays pivotal roles in various cancers. Besides, studies have suggested that GLDC expression is elevated in oral squamous cell carcinoma (OSCC) and associated with a worse prognosis, but the precise role and molecular mechanism of GLDC in OSCC remain unexplored. The current study first confirmed the high expression of GLDC in OSCC and its correlation with worse survival in patients with OSCC. By knocking down GLDC, it was discovered that the growth and colony formation of OSCC cells, as well as the development of xenograft tumors, were effectively suppressed. In addition, GLDC deficiency inhibited the migration and invasion of OSCC cells in vitro through regulating EMT markers and attenuated lung metastasis in vivo. Mechanistically, GLDC was found to affect the activity of the p53 signaling pathway. GLDC depletion retarded the progression of OSCC by activating the p53 signaling pathway. Moreover, p300 co-functioned with TFAP2A to induce acetylation of GLDC, which resulted in the upregulation of GLDC in OSCC. To conclude, acetylation-induced GLDC upregulation facilitated the tumorigenesis and metastasis of OSCC by its inhibition of the activity of the p53 signaling pathway.

5.
J Cardiovasc Pharmacol ; 79(6): 925-934, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35234738

RESUMO

ABSTRACT: Activation of adventitial fibroblasts (AFs) on vascular injury contributes to vascular remodeling. Hydrogen sulfide (H2S), a gaseous signal molecule, modulates various cardiovascular functions. The aim of this study was to explore whether exogenous H2S ameliorates transforming growth factor-ß1 (TGF-ß1)-induced activation of AFs and, if so, to determine the underlying molecular mechanisms. Immunofluorescent staining and western blot were used to determine the expression of collagen I and α-smooth muscle actin. The proliferation and migration of AFs were performed by using cell counting Kit-8 and transwell assay, respectively. The mitochondrial morphology was assessed by using MitoTracker Red staining. The activation of signaling pathway was evaluated by western blot. The mitochondrial reactive oxygen species and mitochondrial membrane potential were determined by MitoSOX and JC-1 (5,5',6,6'-tetrachloro-1,1,3,3'-tetraethylbenzimidazolyl carbocyanine iodide) staining. Our study demonstrated exogenous H2S treatment dramatically suppressed TGF-ß1-induced AF proliferation, migration, and phenotypic transition by blockage of dynamin-related protein 1 (Drp1)-mediated mitochondrial fission and regulated mitochondrial reactive oxygen species generation. Moreover, exogenous H2S reversed TGF-ß1-induced mitochondrial fission and AF activation by modulating Rho-associated protein kinase 1-dependent phosphorylation of Drp1. In conclusion, our results suggested that exogenous H2S attenuates TGF-ß1-induced AF activation through suppression of Drp1-mediated mitochondrial fission in a Rho-associated protein kinase 1-dependent fashion.


Assuntos
Sulfeto de Hidrogênio , Dinâmica Mitocondrial , Células Cultivadas , Fibroblastos/metabolismo , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/farmacologia
6.
Plant Biotechnol J ; 18(4): 1027-1040, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31584248

RESUMO

The molecular basis of cell-cell adhesion in woody tissues is not known. Xylem cells in wood particles of hybrid poplar (Populus tremula × P. alba cv. INRA 717-1B4) were separated by oxidation of lignin with acidic sodium chlorite when combined with extraction of xylan and rhamnogalacturonan-I (RG-I) using either dilute alkali or a combination of xylanase and RG-lyase. Acidic chlorite followed by dilute alkali treatment enables cell-cell separation by removing material from the compound middle lamellae between the primary walls. Although lignin is known to contribute to adhesion between wood cells, we found that removing lignin is a necessary but not sufficient condition to effect complete cell-cell separation in poplar lines with various ratios of syringyl:guaiacyl lignin. Transgenic poplar lines expressing an Arabidopsis thaliana gene encoding an RG-lyase (AtRGIL6) showed enhanced cell-cell separation, increased accessibility of cellulose and xylan to hydrolytic enzyme activities, and increased fragmentation of intact wood particles into small cell clusters and single cells under mechanical stress. Our results indicate a novel function for RG-I, and also for xylan, as determinants of cell-cell adhesion in poplar wood cell walls. Genetic control of RG-I content provides a new strategy to increase catalyst accessibility and saccharification yields from woody biomass for biofuels and industrial chemicals.


Assuntos
Adesão Celular , Pectinas/química , Populus , Madeira/citologia , Parede Celular , Lignina , Plantas Geneticamente Modificadas , Polissacarídeo-Liases/genética
7.
Int J Biometeorol ; 63(3): 381-391, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30694394

RESUMO

Although several studies have demonstrated a short-term association between outdoor temperature and blood pressure (BP) among various adult groups, evidence among children and adolescents is lacking. One hundred ninety-four thousand one hundred four participants from 2016 Health Promotion Program for Children and Adolescents (HPPCA) were analyzed through generalized linear mixed-effects models to estimate the short-term effects of two outdoor temperature variables (average and minimum temperature) on participants' BP. Decreasing outdoor temperature was associated with significant increases in systolic BP (SBP), diastolic BP (DBP), and prevalence of hypertension during lag 0 through lag 6. Additionally, daily minimum temperature showed a more apparent association with participants' BP. The estimated increases (95% confidence interval) in SBP and DBP at lag 0 were 0.82 (0.72, 0.92) mmHg and 2.28 (2.20, 2.35) mmHg for a 1 °C decrease in daily minimum temperature, while those values were 0.11 (0.10, 0.12) mmHg and 0.25 (0.24, 0.26) mmHg for a 1 °C decrease in daily average temperature, respectively. The effects of temperature on BP were stronger among female, as well as those with young age and low body mass index. It demonstrated that short-term decreases in outdoor temperature were significantly associated with rises in BP among children and adolescents. This founding has some implications for clinical management and research of BP. Meanwhile, public health intervention should be designed to reduce the exposure to cold temperature for protecting children and adolescents' BP.


Assuntos
Pressão Sanguínea , Temperatura , Adolescente , Poluentes Atmosféricos/análise , Criança , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Material Particulado/análise
8.
Plant Cell ; 27(12): 3383-96, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26589552

RESUMO

The presence of a large central vacuole is one of the hallmarks of a prototypical plant cell, and the multiple functions of this compartment require massive fluxes of molecules across its limiting membrane, the tonoplast. Transport is assumed to be energized by the membrane potential and the proton gradient established by the combined activity of two proton pumps, the vacuolar H(+)-pyrophosphatase (V-PPase) and the vacuolar H(+)-ATPase (V-ATPase). Exactly how labor is divided between these two enzymes has remained elusive. Here, we provide evidence using gain- and loss-of-function approaches that lack of the V-ATPase cannot be compensated for by increased V-PPase activity. Moreover, we show that increased V-ATPase activity during cold acclimation requires the presence of the V-PPase. Most importantly, we demonstrate that a mutant lacking both of these proton pumps is conditionally viable and retains significant vacuolar acidification, pointing to a so far undetected contribution of the trans-Golgi network/early endosome-localized V-ATPase to vacuolar pH.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Genoma de Planta/genética , Pirofosfatase Inorgânica/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Vacúolos/enzimologia , Aclimatação , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/antagonistas & inibidores , Proteínas de Arabidopsis/genética , Temperatura Baixa , Endossomos/enzimologia , Flores/citologia , Flores/enzimologia , Flores/genética , Flores/fisiologia , Concentração de Íons de Hidrogênio , Pirofosfatase Inorgânica/antagonistas & inibidores , Pirofosfatase Inorgânica/genética , Meristema/citologia , Meristema/enzimologia , Meristema/genética , Meristema/fisiologia , Mutagênese Insercional , Fenótipo , Raízes de Plantas/citologia , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Plântula/citologia , Plântula/enzimologia , Plântula/genética , Plântula/fisiologia , Análise de Sequência de DNA , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidores , ATPases Vacuolares Próton-Translocadoras/genética , Rede trans-Golgi/enzimologia
9.
J Cardiovasc Pharmacol ; 71(6): 367-374, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29642134

RESUMO

BACKGROUND AND OBJECTIVE: Allitridin [diallyl trisulfide (DATS)] is an extract from garlic (Allium sativum) that putatively improves endothelial function and is protective against cardiovascular diseases. Endothelial dysfunction after tissue ischemia in diabetic patients is partially due to poor angiogenic response. This study investigated whether DATS may improve angiogenesis in a diabetic mouse model with hind limb ischemia. METHODS: Streptozotocin was administered by intraperitoneal injection to establish the model of diabetes in male C57BL/6 mice. After 14 days, nondiabetic and diabetic mice (n = 24, each) underwent unilateral hind limb ischemia by femoral artery ligation. The mice were apportioned to 4 groups: nondiabetic treated (or not) with DATS and diabetic treated (or not) with DATS. DATS treatment consisted of a single daily intraperitoneal injection of 500 µg·kg·d for 14 days, beginning on the day of induced ischemia. Ischemia was scored by standard criteria. Blood perfusion was determined using thermal infrared imaging. Tissue capillary density and oxidative stress levels were measured by immunohistochemistry and immunofluorescence, respectively. Serum lipids were measured by enzymatic colorimetric assay. Fasting serum insulin was detected using an insulin enzyme-linked immunosorbent assay kit. Nitric oxide (NO) metabolites and protein carbonyls in tissues were determined by enzyme-linked immunosorbent assay. Targeted protein concentrations were measured by western blotting. RESULTS: At 14 days after ligation, the ischemic skeletal muscle of the streptozotocin-induced diabetic mice had lower levels of endothelial NO synthase, phosphorylated endothelial NO synthase, and vascular endothelial growth factor compared with nondiabetic group. In addition, the hind limb blood perfusion, capillary density, and NO bioactivity were lower in the diabetic group, whereas oxidative stress and protein carbonyl levels were higher. These changes were ameliorated by DATS treatment. CONCLUSIONS: DATS treatment of diabetic mice promoted revascularization in ischemic tissue.


Assuntos
Compostos Alílicos/farmacologia , Indutores da Angiogênese/farmacologia , Diabetes Mellitus Experimental/complicações , Angiopatias Diabéticas/tratamento farmacológico , Isquemia/tratamento farmacológico , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica/efeitos dos fármacos , Sulfetos/farmacologia , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/fisiopatologia , Membro Posterior , Isquemia/etiologia , Isquemia/metabolismo , Isquemia/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Carbonilação Proteica/efeitos dos fármacos , Fluxo Sanguíneo Regional , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Clin Exp Hypertens ; : 1-7, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29553835

RESUMO

The purpose of this study was to analyze the association between resting heart rate (RHR) and prevalence of hypertension in Chinese children and to identify if this association was mediated by body mass index (BMI). The data of 5445 children who participated in the Blood Pressure Surveillance Program (2011-2017) were analyzed in this study. Children were divided into four groups according to quartiles of RHR in boys and girls, respectively. Compared to those in the first quartile, boys and girls in the fourth quartile were 3.06 (95% CI 2.12, 4.41) and 4.94 (95% CI 3.21, 7.61) times more likely to have hypertension, respectively. Meanwhile, every 10 beats per minute (bpm) increase in RHR was associated with a 41% (95% CI 1.27, 1.56) and 66% (95% CI 1.49, 1.85) greater risk of hypertension in boys and girls, respectively. There were no significant interactions between RHR and BMI on the prevalence of hypertension. This study confirms the existence of a relationship between elevated RHR and increased risk of hypertension in children, independent of BMI. An elevated RHR could be considered as a risk factor for the risk assessment of hypertension, no matter from a clinical setting or a public health perspective.

11.
J Exp Bot ; 68(16): 4627-4634, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28981783

RESUMO

WRINKLED1 (WRI1) is a key transcriptional regulator of fatty acid biosynthesis genes in diverse oil-containing tissues. Loss of function of Arabidopsis WRI1 leads to a reduction in the expression of genes for fatty acid biosynthesis and glycolysis, and concomitant strong reduction of seed oil content. The wri1-1 loss-of-function mutant shows reduced primary root growth and decreased acidification of the growth medium. The content of a conjugated form of the plant growth hormone auxin, indole-3-acetic acid (IAA)-Asp, was higher in wri1-1 plants compared with the wild-type. GH3.3, a gene encoding an enzyme involved in auxin degradation, displayed higher expression in the wri1-1 mutant. EMSAs demonstrated that AtWRI1 bound to the promoter of GH3.3. Specific AtWRI1-binding motifs were identified in the promoter of GH3.3. In addition, wri1-1 displayed decreased auxin transport. Expression of some PIN genes, which encode IAA carrier proteins, was reduced in wri1-1 plants as well. Correspondingly, AtWRI1 bound to the promoter regions of some PIN genes. It is well known that auxin exerts its maximum effects at a specific, optimal concentration in roots requiring a finely balanced auxin homeostasis. This process appears to be disrupted when the expression of WRI1 and in turn a subset of its target genes are misregulated, highlighting a role for WRI1 in root auxin homeostasis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sítios de Ligação , Transporte Biológico/genética , Regulação da Expressão Gênica de Plantas , Homeostase , Proteínas de Membrana Transportadoras/genética , Mutação , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Fatores de Transcrição/genética
12.
Plant Biotechnol J ; 14(10): 1998-2009, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26929151

RESUMO

Conversion of nongrain biomass into liquid fuel is a sustainable approach to energy demands as global population increases. Previously, we showed that iron can act as a catalyst to enhance the degradation of lignocellulosic biomass for biofuel production. However, direct addition of iron catalysts to biomass pretreatment is diffusion-limited, would increase the cost and complexity of biorefinery unit operations and may have deleterious environmental impacts. Here, we show a new strategy for in planta accumulation of iron throughout the volume of the cell wall where iron acts as a catalyst in the deconstruction of lignocellulosic biomass. We engineered CBM-IBP fusion polypeptides composed of a carbohydrate-binding module family 11 (CBM11) and an iron-binding peptide (IBP) for secretion into Arabidopsis and rice cell walls. CBM-IBP transformed Arabidopsis and rice plants show significant increases in iron accumulation and biomass conversion compared to respective controls. Further, CBM-IBP rice shows a 35% increase in seed iron concentration and a 40% increase in seed yield in greenhouse experiments. CBM-IBP rice potentially could be used to address iron deficiency, the most common and widespread nutritional disorder according to the World Health Organization.


Assuntos
Arabidopsis/metabolismo , Biomassa , Parede Celular/metabolismo , Ferro/metabolismo , Oryza/metabolismo , Sementes/metabolismo , Arabidopsis/genética , Biocombustíveis , Parede Celular/genética , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
Plant Cell ; 24(7): 2874-85, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22773749

RESUMO

Auxin transport, which is mediated by specialized influx and efflux carriers, plays a major role in many aspects of plant growth and development. AUXIN1 (AUX1) has been demonstrated to encode a high-affinity auxin influx carrier. In Arabidopsis thaliana, AUX1 belongs to a small multigene family comprising four highly conserved genes (i.e., AUX1 and LIKE AUX1 [LAX] genes LAX1, LAX2, and LAX3). We report that all four members of this AUX/LAX family display auxin uptake functions. Despite the conservation of their biochemical function, AUX1, LAX1, and LAX3 have been described to regulate distinct auxin-dependent developmental processes. Here, we report that LAX2 regulates vascular patterning in cotyledons. We also describe how regulatory and coding sequences of AUX/LAX genes have undergone subfunctionalization based on their distinct patterns of spatial expression and the inability of LAX sequences to rescue aux1 mutant phenotypes, respectively. Despite their high sequence similarity at the protein level, transgenic studies reveal that LAX proteins are not correctly targeted in the AUX1 expression domain. Domain swapping studies suggest that the N-terminal half of AUX1 is essential for correct LAX localization. We conclude that Arabidopsis AUX/LAX genes encode a family of auxin influx transporters that perform distinct developmental functions and have evolved distinct regulatory mechanisms.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Transporte Biológico , Padronização Corporal , Cotilédone/citologia , Cotilédone/genética , Cotilédone/crescimento & desenvolvimento , Cotilédone/metabolismo , Técnicas de Inativação de Genes , Proteínas de Membrana Transportadoras/genética , Família Multigênica , Mutagênese Insercional , Fenótipo , Raízes de Plantas/citologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Feixe Vascular de Plantas/citologia , Feixe Vascular de Plantas/genética , Feixe Vascular de Plantas/crescimento & desenvolvimento , Feixe Vascular de Plantas/metabolismo , Plantas Geneticamente Modificadas , Plântula/citologia , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
14.
Plant J ; 74(1): 37-47, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23279701

RESUMO

The Arabidopsis ATP-binding cassette B19 (ABCB19, P-glycoprotein19) transporter functions coordinately with ABCB1 and PIN1 to motivate long-distance transport of the phytohormone auxin from the shoot to root apex. ABCB19 exhibits a predominantly apolar plasma membrane (PM) localization and stabilizes PIN1 when the two proteins co-occur. Biochemical evidence associates ABCB19 and PIN1 with sterol- and sphingolipid-enriched PM fractions. Mutants deficient in structural sterols and sphingolipids exhibit similarity to abcb19 mutants. Sphingolipid-defective tsc10a mutants and, to a lesser extent, sterol-deficient cvp1 mutants phenocopy abcb19 mutants. Live imaging studies show that sterols function in trafficking of ABCB19 from the trans-Golgi network to the PM. Pharmacological or genetic sphingolipid depletion has an even greater impact on ABCB19 PM targeting and interferes with ABCB19 trafficking from the Golgi. Our results also show that sphingolipids function in trafficking associated with compartments marked by the VTI12 syntaxin, and that ABCB19 mediates PIN1 stability in sphingolipid-containing membranes. The TWD1/FKBP42 co-chaperone immunophilin is required for exit of ABCB19 from the ER, but ABCB19 interactions with sterols, sphingolipids and PIN1 are spatially distinct from FKBP42 activity at the ER. The accessibility of this system to direct live imaging and biochemical analysis makes it ideal for the modeling and analysis of sterol and sphingolipid regulation of ABCB/P-glycoprotein transporters.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Esfingolipídeos/metabolismo , Esteróis/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/metabolismo , Mutação , Transporte Proteico , Proteínas de Ligação a Tacrolimo/metabolismo , Rede trans-Golgi/metabolismo
15.
J Exp Bot ; 65(12): 3045-53, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24723407

RESUMO

Phosphorus (P), an element required for plant growth, fruit set, fruit development, and fruit ripening, can be deficient or unavailable in agricultural soils. Previously, it was shown that over-expression of a proton-pyrophosphatase gene AVP1/AVP1D (AVP1DOX) in Arabidopsis, rice, and tomato resulted in the enhancement of root branching and overall mass with the result of increased mineral P acquisition. However, although AVP1 over-expression also increased shoot biomass in Arabidopsis, this effect was not observed in tomato under phosphate-sufficient conditions. AVP1DOX tomato plants exhibited increased rootward auxin transport and root acidification compared with control plants. AVP1DOX tomato plants were analysed in detail under limiting P conditions in greenhouse and field trials. AVP1DOX plants produced 25% (P=0.001) more marketable ripened fruit per plant under P-deficient conditions compared with the controls. Further, under low phosphate conditions, AVP1DOX plants displayed increased phosphate transport from leaf (source) to fruit (sink) compared to controls. AVP1DOX plants also showed an 11% increase in transplant survival (P<0.01) in both greenhouse and field trials compared with the control plants. These results suggest that selection of tomato cultivars for increased proton pyrophosphatase gene expression could be useful when selecting for cultivars to be grown on marginal soils.


Assuntos
Proteínas de Arabidopsis/genética , Frutas/enzimologia , Pirofosfatase Inorgânica/genética , Raízes de Plantas/enzimologia , Solanum lycopersicum/enzimologia , Solanum lycopersicum/crescimento & desenvolvimento , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Expressão Gênica , Pirofosfatase Inorgânica/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Fósforo/metabolismo , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo
16.
PLoS Biol ; 9(6): e1001076, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21666806

RESUMO

It is well accepted that lateral redistribution of the phytohormone auxin underlies the bending of plant organs towards light. In monocots, photoreception occurs at the shoot tip above the region of differential growth. Despite more than a century of research, it is still unresolved how light regulates auxin distribution and where this occurs in dicots. Here, we establish a system in Arabidopsis thaliana to study hypocotyl phototropism in the absence of developmental events associated with seedling photomorphogenesis. We show that auxin redistribution to the epidermal sites of action occurs at and above the hypocotyl apex, not at the elongation zone. Within this region, we identify the auxin efflux transporter ATP-BINDING CASSETTE B19 (ABCB19) as a substrate target for the photoreceptor kinase PHOTOTROPIN 1 (phot1). Heterologous expression and physiological analyses indicate that phosphorylation of ABCB19 by phot1 inhibits its efflux activity, thereby increasing auxin levels in and above the hypocotyl apex to halt vertical growth and prime lateral fluxes that are subsequently channeled to the elongation zone by PIN-FORMED 3 (PIN3). Together, these results provide new insights into the roles of ABCB19 and PIN3 in establishing phototropic curvatures and demonstrate that the proximity of light perception and differential phototropic growth is conserved in angiosperms.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Fosfoproteínas/metabolismo , Fototropismo , Brotos de Planta/metabolismo , Aclimatação , Arabidopsis/crescimento & desenvolvimento , Transporte Biológico , Escuridão , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Hipocótilo/metabolismo , Mutação/genética , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases , Proteínas Recombinantes de Fusão/metabolismo
17.
Proc Natl Acad Sci U S A ; 108(44): 18179-84, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22006310

RESUMO

An effective plant alkaloid chemical defense requires a variety of transport processes, but few alkaloid transporters have been characterized at the molecular level. Previously, a gene fragment encoding a putative plasma membrane proton symporter was isolated, because it was coordinately regulated with several nicotine biosynthetic genes. Here, we show that this gene fragment corresponds to a Nicotiana tabacum gene encoding a nicotine uptake permease (NUP1). NUP1 belongs to a plant-specific class of purine uptake permease-like transporters that originated after the bryophytes but before or within the lycophytes. NUP1 expressed in yeast cells preferentially transported nicotine relative to other pyridine alkaloids, tropane alkaloids, kinetin, and adenine. NUP1-GFP primarily localized to the plasma membrane of tobacco Bright Yellow-2 protoplasts. WT NUP1 transcripts accumulated to high levels in the roots, particularly in root tips. NUP1-RNAi hairy roots had reduced NUP1 mRNA accumulation levels, reduced total nicotine levels, and increased nicotine accumulation in the hairy root culture media. Regenerated NUP1-RNAi plants showed reduced foliar and root nicotine levels as well as increased seedling root elongation rates. Thus, NUP1 affected nicotine metabolism, localization, and root growth.


Assuntos
Alcaloides/metabolismo , Nicotiana/metabolismo , Nicotina/metabolismo , Genes de Plantas , Dados de Sequência Molecular , Nicotiana/genética
18.
Histol Histopathol ; 39(10): 1359-1370, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38469708

RESUMO

Lymphocyte antigen 6 complex locus K (LY6K) has been demonstrated to play a significant role in cancers and identified as a therapeutic biomarker for head and neck squamous cell carcinoma. However, the role of LY6K in oral squamous cell carcinoma (OSCC) has not been explored. The current study discovered that LY6K was aberrantly upregulated in OSCC cell lines and tissues and that high LY6K expression significantly correlated with poorer survival of OSCC patients. Through stable knockdown of LY6K, we found that the growth, colony formation, migration, and invasion of OSCC cells were substantially suppressed. In addition, tumor growth and lung metastasis in vivo were effectively inhibited by LY6K depletion. Mechanically, LY6K binds with CAV-1 and activates CAV-1-mediated MAPK/ERK signaling to exert its oncogenic effects on OSCC. In addition, LY6K expression in OSCC was discovered to be regulated by FTO-mediated RNA N6-methyladenosine (m6A) modification in an IGF2BP1-dependent manner. Generally, LY6K expression was upregulated by FTO-mediated demethylation in OSCC, which promoted the tumorigenesis and metastasis of OSCC via activating the CAV-1-mediated ERK1/2 signaling pathway.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato , Antígenos Ly , Caveolina 1 , Regulação Neoplásica da Expressão Gênica , Sistema de Sinalização das MAP Quinases , Neoplasias Bucais , Regulação para Cima , Humanos , Neoplasias Bucais/patologia , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Antígenos Ly/metabolismo , Antígenos Ly/genética , Caveolina 1/metabolismo , Caveolina 1/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Linhagem Celular Tumoral , Animais , Proteínas Ligadas por GPI/metabolismo , Proteínas Ligadas por GPI/genética , Carcinogênese/genética , Carcinogênese/metabolismo , Desmetilação , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/genética , Camundongos , Camundongos Nus , Movimento Celular
19.
Int J Transgend Health ; 25(3): 602-618, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39055635

RESUMO

Background: Ensuring proper early feeding for young children is crucial, as encountering feeding difficulties (FD) during this stage can give rise to a cascade of health problems, the repercussions of which may endure into late childhood and adolescence. Children raised by transgender parents may be at risk of encountering FD, however, there is no research conducted on Chinese transgender families. Methods: We designed a cross-sectional survey in which the rate of FD and its influencing factors were investigated among transgender parents in China. A total of 446 Chinese transgender parents (average age 30.39 years) were included in the analysis. Logistic regression models were applied to investigate the influencing factors of FD among children of transgender parents. We also established structural equation modeling (SEM) to explore the possible pathways among these factors and FD. Results: The rate of FD in children of Chinese transgender parents is 55.4%, with 34.5% having severe FD. Coming out after having a child (AOR = 2.26, 95%CI = 1.33 ∼ 3.91), family violence (AOR = 1.06, 95%CI = 1.04 ∼ 1.09), partner violence (AOR = 1.11, 95%CI = 1.08 ∼ 1.15), no feeding education (accepting feeding education: AOR = 0.43, 95%CI = 0.25 ∼ 0.74), being discriminated during seeking of childbearing health care (AOR = 1.99, 95%CI = 1.3 ∼ 3.05), and poor relationship with partner (fair: AOR = 0.09, 95%CI = 0.03 ∼ 0.22; good: AOR = 0.06, 95%CI = 0.02 ∼ 0.15) are significantly associated with higher FD. Furthermore, through the pathway analysis, the indirect effects of education level (ß=-0.151), feeding education (ß = 0.145), and relationship with partner (ß=-0.196) on FD are observed. Conclusions: Children of Chinese transgender parents showed a high FD rate. It is crucial to help build a better family and social environment for transgender families to reduce the FD and improve children's and adolescents' health.

20.
Nutr Rev ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820346

RESUMO

CONTEXT: The COVID-19 pandemic has had a global impact on food security and nutrition, both in the short and long term. The influence on school-age children, adolescents, and young adults may be particularly significant and long-lasting. OBJECTIVE: This systematic review and meta-analysis aimed to quantify the impact of the COVID-19 pandemic on dietary habits among school-age children, adolescents, and young adults worldwide. DATA SOURCES: PubMed, Web of Science, and Embase were searched from inception to October 5, 2023. DATA EXTRACTION: We included observational studies published in English that reported dietary quality scores and dietary intake quantities during and before the COVID-19 pandemic among school-age children, adolescents, and young adults. We included a total of 22 cohort studies and 20 cross-sectional studies of high or moderate quality. DATA ANALYSIS: We conducted a meta-analysis, expressing dietary quality scores and dietary intake quantities as standardized mean differences (SMD) with 95% confidence intervals (CIs). For studies with low heterogeneity, we used a fixed-effects model; otherwise, we applied a random-effects model. The Newcastle-Ottawa Scale was employed by 2 reviewers independently to evaluate methodological quality. The analysis indicated that, overall, juice intake increased (SMD = 0.12, 95% CI: 0.04 to 0.20), while alcohol consumption reduced during the COVID-19 pandemic (SMD = -0.28, 95% CI: -0.47 to -0.08). However, the age-stratified results varied. Among school-age children, intake of fruit, dairy products, sugar, and juice increased. Adolescents showed an increase in meal frequency and vegetable intake. Young adults showed reduced carbohydrate and alcohol intakes, while protein and dairy product intakes increased, based on limited included studies. CONCLUSION: Dietary changes in school-age children from before to during the pandemic were mixed, while dietary behavior changes in adolescents and young adults tended to be more positive. Considering the lasting effects of negative dietary behaviors, attention should be given to addressing the increased sugar and juice intakes. It is also crucial that caregivers and researchers monitor whether positive dietary behaviors will rebound after returning to normal study and life. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42023420923.

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