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1.
J Nutr ; 154(2): 314-324, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38042352

RESUMO

The composition of human milk is influenced by storage and processing practices. The effects of thawing and warming practices on human milk composition remain poorly studied despite their prevalence in home, research, and donor milk bank settings. This review comprehensively examines the impact of different thawing and warming methods on nutritional and bioactive human milk components. While some components such as carbohydrates and minerals remain stable under most typical thawing and warming conditions, others, such as fat, immune proteins, bacterial and human cells, and peptide amine hormones, are sensitive to warming. This review has identified that the data on the effects of milk thawing and warming is limited and often contradictory. Given that numerous important components of milk are diminished during cold storage, it is important that thawing and warming practices do not lead to further loss of or alterations to beneficial milk components. Further work in this field will facilitate greater standardization of thawing methods among researchers and underpin recommendations for thawing and warming of expressed milk for parents.


Assuntos
Bancos de Leite Humano , Leite Humano , Humanos , Leite Humano/química , Carboidratos , Minerais/análise
2.
Plant Cell ; 29(8): 2016-2026, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28739644

RESUMO

Potassium and nitrogen are essential macronutrients for plant growth and have a positive impact on crop yield. Previous studies have indicated that the absorption and translocation of K+ and NO3- are correlated with each other in plants; however, the molecular mechanism that coordinates K+ and NO3- transport remains unknown. In this study, using a forward genetic approach, we isolated a low-K+-sensitive Arabidopsis thaliana mutant, lks2, that showed a leaf chlorosis phenotype under low-K+ conditions. LKS2 encodes the transporter NRT1.5/NPF7.3, a member of the NRT1/PTR (Nitrate Transporter 1/Peptide Transporter) family. The lks2/nrt1.5 mutants exhibit a remarkable defect in both K+ and NO3- translocation from root to shoot, especially under low-K+ conditions. This study demonstrates that LKS2 (NRT1.5) functions as a proton-coupled H+/K+ antiporter. Proton gradient can promote NRT1.5-mediated K+ release out of root parenchyma cells and facilitate K+ loading into the xylem. This study reveals that NRT1.5 plays a crucial role in K+ translocation from root to shoot and is also involved in the coordination of K+/NO3- distribution in plants.


Assuntos
Proteínas de Transporte de Ânions/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Antiportadores de Potássio-Hidrogênio/metabolismo , Potássio/metabolismo , Prótons , Xilema/metabolismo , Animais , Transporte Biológico , Cátions/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Mutação/genética , Nitratos/metabolismo , Oócitos/metabolismo , Fenótipo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência de Aminoácidos , Estresse Fisiológico , Xenopus laevis
3.
Plant Cell ; 24(12): 5106-22, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23232097

RESUMO

Protein ubiquitination is a reversible process catalyzed by ubiquitin ligases and ubiquitin-specific proteases (UBPs). We report the identification and characterization of UBP16 in Arabidopsis thaliana. UBP16 is a functional ubiquitin-specific protease and its enzyme activity is required for salt tolerance. Plants lacking UBP16 were hypersensitive to salt stress and accumulated more sodium and less potassium. UBP16 positively regulated plasma membrane Na(+)/H(+) antiport activity. Through yeast two-hybrid screening, we identified a putative target of UBP16, SERINE HYDROXYMETHYLTRANSFERASE1 (SHM1), which has previously been reported to be involved in photorespiration and salt tolerance in Arabidopsis. We found that SHM1 is degraded in a 26S proteasome-dependent process, and UBP16 stabilizes SHM1 by removing the conjugated ubiquitin. Ser hydroxymethyltransferase activity is lower in the ubp16 mutant than in the wild type but higher than in the shm1 mutant. During salt stress, UBP16 and SHM1 function in preventing cell death and reducing reactive oxygen species accumulation, activities that are correlated with increasing Na(+)/H(+) antiport activity. Overexpression of SHM1 in the ubp16 mutant partially rescues its salt-sensitive phenotype. Taken together, our results suggest that UBP16 is involved in salt tolerance in Arabidopsis by modulating sodium transport activity and repressing cell death at least partially through modulating SMH1stability and activity.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/metabolismo , Glicina Hidroximetiltransferase/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Glicina Hidroximetiltransferase/química , Glicina Hidroximetiltransferase/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estabilidade Proteica/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Trocadores de Sódio-Hidrogênio/genética , Trocadores de Sódio-Hidrogênio/metabolismo
4.
Funct Plant Biol ; 512024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39402699

RESUMO

The Chinese gentian, Gentiana sino-ornata produces brilliant blue flowers. To investigate the biological function and transcriptional regulation mechanism of the anthocyanin 5-O-acyltransferase gene (Gs5AT ) in the corolla, it is beneficial to analyse the mechanism of blue flower colour presentation. In this investigation, we obtained the CDS and promoter sequences of the gene Gs5AT . Yeast one-hybrid experiments were used to identify the transcription factor GsbHLH7 that activates the gene Gs5AT . According to quantitive reverse transcription polymerase chain reaction analysis, the expression of the gene Gs5AT was significantly and positively correlated with the gene GsbHLH7 . The colour phenotype of the flowers was significantly altered by the virus-induced gene silencing transduction of Gs5AT and GsbHLH7 , with GsbHLH7 silencing producing more pronounced changes in the corolla colour than Gs5AT . The expression of GsF3'5'H , GsDFR , GsANS , Gs3GT , and Gs5GT all fell to varying degrees after GsbHLH7 silencing, indicating that GsbHLH7 may regulate transcription of these genes as well as Gs5AT . The results of this study indicate that Gs5AT was positively regulated by the GsbHLH7 , and thus affects the colour presentation of the blue corolla.


Assuntos
Antocianinas , Flores , Regulação da Expressão Gênica de Plantas , Gentiana , Proteínas de Plantas , Gentiana/genética , Gentiana/metabolismo , Antocianinas/metabolismo , Antocianinas/biossíntese , Antocianinas/genética , Flores/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Inativação Gênica , Aciltransferases/genética , Aciltransferases/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica
5.
Adv Nutr ; 15(1): 100129, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37832920

RESUMO

Low milk supply (LMS) poses a significant challenge to exclusive and continued breastfeeding, affecting ∼10% to 15% of mothers. Milk production is intricately regulated by both endocrine and autocrine control mechanisms, with estrogens and progesterone playing pivotal roles in this process. In addition to endogenously produced hormones, external substances capable of interfering with normal hormonal actions, including phytoestrogens, mycoestrogens, synthetic estrogens, and hormonal contraceptives, can influence milk production. The effects of these extrinsic hormones on milk production may vary based on maternal body mass index. This comprehensive review examines the multifaceted causes of LMS, focusing on the involvement of estrogens, progesterone, and related external factors in milk production. Furthermore, it investigates the interplay between hormonal factors and obesity, aiming to elucidate the endocrine mechanisms underlying obesity-associated LMS. Insights from this review provide valuable perspectives for developing interventions to improve milk production and address the challenges associated with LMS.


Assuntos
Estrogênios , Progesterona , Feminino , Humanos , Animais , Progesterona/farmacologia , Estrogênios/farmacologia , Leite , Lactação , Obesidade
6.
Nutrients ; 16(17)2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39275171

RESUMO

BACKGROUND: Maternal breast volume is determined by the quantity of glandular and adipose tissue, and it undergoes significant changes during pregnancy. These changes are intricately linked to the development of glandular tissue, which most likely reflects lactation capacity. Evidence indicates that women with overweight or obesity exhibit larger breast volume compared to those with a normal body mass index (BMI), emphasizing the close relationship between breast volume and maternal adiposity. Hence, we aim to investigate breast volume growth and maternal BMI as potential risk factors for low milk production. METHODS: Lactating women (n = 609) from the Perth metropolitan area in Western Australia between 2011 and 2023 were included in the analysis. Twenty-four-hour milk production measurements were conducted using the test weighing method, and milk removal frequencies were recorded. Mothers completed questionnaires regarding demographic, obstetric and infant details. Linear and logistic regression models were used to determine maternal and infant factors associated with milk production. RESULTS: Here we show that increasing maternal age and BMI are associated with low milk production. Moreover, larger pre-pregnancy breast volume and breast growth are associated with both higher BMI and milk production. CONCLUSIONS: Women who are older, have an obese BMI and who have minimal pre-pregnancy breast volume and breast growth should be provided with antenatal screening and breastfeeding support as they are more likely to experience low milk production.


Assuntos
Índice de Massa Corporal , Mama , Lactação , Leite Humano , Humanos , Feminino , Adulto , Lactação/fisiologia , Mama/crescimento & desenvolvimento , Gravidez , Austrália Ocidental/epidemiologia , Aleitamento Materno , Idade Materna , Obesidade , Fatores de Risco , Adulto Jovem
7.
Endocr Res ; 38(2): 59-68, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23544998

RESUMO

The recent genome-wide association studies reveal that chromosome 3q resides within the linkage region for diabetic nephropathy (DN) in type 1 and type 2 diabetes mellitus (T1D and T2D). The TRPC1 gene is on chromosome 3q22-24, and it has been demonstrated that TRPC1 expression is reduced in the kidney of diabetic animal models. Genetic association of TRPC1 polymorphism with T1D and DN has been reported in European Americans. However, there are no studies reporting the association of TRPC1 genetic polymorphism with T2D with and without DN in Chinese population. This study aimed to demonstrate the genetic role of TRPC1 in the development of T2D with and without DN in Chinese Han population. A genetic association study of TRPC1 was performed in T2D cases and in nondiabetic controls from Han population located in Northern Chinese areas. Six tag single nucleotide polymorphism (SNP) markers derived from HapMap data were genotyped. Among the six SNPs, only rs7638459 was suspected as risk factor of T2D without DN, fitting the log-additive model. The adjusted odds ratio (OR) for the CC genotyping was 2.39 (95% confidence interval (CI) = 1.00-5.68), compared with the TT genotyping. In addition, rs953239 was found to be a protective factor of getting DN in T2D, also fitting the log-additive model. When compared with the AA genotyping for SNP rs953239, the adjusted OR for CC genotyping was 0.63 (95% CI = 0.44-0.99). To summarize, this study shows that TRPC1 genetic polymorphisms are associated with T2D and DN in T2D in the Han Chinese population.


Assuntos
Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/genética , Predisposição Genética para Doença/etnologia , Polimorfismo de Nucleotídeo Único/genética , Canais de Cátion TRPC/genética , Estudos de Casos e Controles , China/etnologia , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
8.
Food Chem ; 424: 136375, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37209436

RESUMO

Human milk (HM) is a complex biological system that contains a wide range of bioactive components including oestrogens and progesterone. Whilst maternal oestrogens and progesterone concentrations drop rapidly after birth, they remain detectable in HM across lactation. Phytoestrogens and mycoestrogens, which are produced by plants and fungi, are also present in HM and can interact with oestrogen receptors to interfere with normal hormone functions. Despite the potential impact of HM oestrogens and progesterone on the infant, limited research has addressed their impact on the growth and health of breastfed infants. Furthermore, it is important to comprehensively understand the factors that contribute to these hormone levels in HM, in order to establish effective intervention strategies. In this review, we have summarized the concentrations of naturally occurring oestrogens and progesterone in HM from both endogenous and exogenous sources and discussed both maternal factors impacting HM levels and relationships with infant growth.


Assuntos
Leite Humano , Progesterona , Lactente , Feminino , Humanos , Saúde do Lactente , Aleitamento Materno , Lactação/fisiologia , Estrogênios
9.
J Food Sci ; 85(6): 1635-1641, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32449945

RESUMO

Soymilk has a complicated system, and its sensory and physicochemical characteristics are influenced by the components of the soybean seeds. Thirty-five soybean cultivars were selected, and correlation analysis and clustering analysis were applied to determine the significant correlations between soybean seed traits and soymilk physiochemical properties. Four sensory quality attributes of soymilk, including taste, odor, appearance, and mouthfeel, were quantified in numerical values and scored based on a weighting criterion which was constructed via the fuzzy logic technique. Soymilk prepared from the soybean seeds with the lower crude protein and the higher crude fat content displayed better sensory qualities. A multivariate linear regression analysis was used to establish a predictive model for overall sensory scores of soymilk, which could be the reference for soybean cultivars selection in soymilk processing. To comprehensively optimize the processing costs, nutritional values, and sensory qualities, a set of detailed attributes of soybean seeds were recommended based on this study: 100-seed weight is higher than 20 g; ash content is less than 5.5 g/100 g; crude fat content is 20 to 24 g/100 g; and crude protein content is as high as possible, while the maximum limit is 40 g/100 g. PRACTICAL APPLICATION: The established predictive model can be a reference for soybean cultivars selection in soymilk processing. Moreover, the soybean composition range that is revealed by this study also provides a recommendation for the soybean breeding.


Assuntos
Leite de Soja/química , Leite de Soja/metabolismo , Cruzamento , Lógica Fuzzy , Humanos , Valor Nutritivo , Odorantes/análise , Fenótipo , Sementes/química , Sementes/metabolismo , Glycine max/química , Glycine max/metabolismo , Paladar
10.
Front Plant Sci ; 7: 1307, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27656188

RESUMO

The cyanidin (Cy), pelargonidin (Pg), and delphinidin (Dp) pathways are the three major branching anthocyanin biosynthesis pathways that regulate flavonoid metabolic flux and are responsible for red, orange, and blue flower colors, respectively. Different species have evolved to develop multiple regulation mechanisms that form the branched pathways. In the current study, five Senecio cruentus cultivars with different colors were investigated. We found that the white and yellow cultivars do not accumulate anthocyanin and that the blue, pink, and carmine cultivars mainly accumulate Dp, Pg, and Cy in differing densities. Subsequent transcriptome analysis determined that there were 43 unigenes encoding anthocyanin biosynthesis genes in the blue cultivar. We also combined chemical and transcriptomic analyses to investigate the major metabolic pathways that are related to the observed differences in flower pigmentation in the series of S. cruentus. The results showed that mutations of the ScbHLH17 and ScCHI1/2 coding regions abolish anthocyanin formation in the white and the yellow cultivars; the competition of the ScF3'H1, ScF3'5'H, and ScDFR1/2 genes for naringenin determines the differences in branching metabolic flux of the Cy, Dp, and Pg pathways. Our findings provide new insights into the regulation of anthocyanin branching and also supplement gene resources (including ScF3'5 'H, ScF3'H, and ScDFRs) for flower color modification of ornamentals.

12.
Nat Prod Res ; 29(8): 698-702, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25421438

RESUMO

A new chromene, acetic acid 2R-(4,8-dimethylnona-3,7-dienyl)-8-hydroxy-2-methyl-2H-chromen-6-yl ester (1), was isolated from the fruiting bodies of Chroogomphus rutilus, together with six known compounds (2-7). The structures of these compounds were identified based on 1D and 2D NMR, including (1)H-(1)H COSY, HMQC and HMBC spectroscopic methods. Of these seven compounds, 2 and 3 showed cytotoxicity against HSC-T6, SK-Hep1 and A549 cell lines.


Assuntos
Basidiomycota/química , Benzopiranos/química , Benzopiranos/isolamento & purificação , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Estrutura Molecular
13.
Sheng Wu Gong Cheng Xue Bao ; 30(6): 848-63, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25212003

RESUMO

Anthocyanin biosynthesis is one of the thoroughly studied enzymatic pathways in biology, but little is known about the molecular mechanisms of its final stage: the transport of the anthocyanins into the vacuole. A clear picture of the dynamic trafficking of flavonoids is only now beginning to emerge. So far four different models have been proposed to explain the transport of anthocyanins from biosynthetic sites to the central vacuole, and four types of transporters have been found associated with the transport of anthocyanins: glutathione S-transferase, multidrug resistance-associated protein, multidrug and toxic compound extrusion, bilitranslocase-homologue. The functions of these proteins and related genes have also been studied. Although different models have been proposed, cellular and subcellular information is still lacking for reconciliation of different lines of evidence in various anthocyanin sequestration studies. According to the information available, through sequence analysis, gene expression analysis, subcellular positioning and complementation experiments, the function and location of these transporters can be explored, and the anthocyanin transport mechanism can be better understood.


Assuntos
Antocianinas/metabolismo , Plantas/metabolismo , Transporte Biológico , Glutationa Transferase/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Vacúolos/metabolismo
14.
Mol Med Rep ; 9(4): 1165-70, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24535566

RESUMO

Vitamin D signaling not only controls calcium (Ca2+) and phosphorus uptake and transport, but also correlates with neurocognitive decline and neurodegenerative diseases. Almost all actions of Vitamin D are mediated by the transcription factor, vitamin D receptor (VDR), which has been widely identified in the central nervous system. Although previous studies have substantially advanced the understanding of the action of VDR in the brain, much remains unknown concerning how VDR relates to stress. Multiple lines of evidence indicate that the downregulation of L-type voltage-sensitive Ca2+-channels α-1C (LVSCC-A1C) by vitamin D in hippocampal neurons is able to reduce the influx and excitotoxic effects of Ca2+ to neurons. Along these lines, the purpose of the present study was to analyze the relative expression of VDR in the hippocampus of rats exposed to single prolonged stress (SPS) as a putative animal model for human post-traumatic stress disorder (PTSD). Furthermore, changes in the levels of expression of LVSCC-A1C and Ca2+ (neurotransmitter content) were examined during the onset periods of PTSD. The results revealed an increase in the expression of VDR at 1, 3 and 7 days post-stress compared with the control group. The intracellular free Ca2+ levels in the hippocampus increased 1 day after SPS exposure, and then decreased gradually to the normal level at 14 days, consistent with the expression pattern of LVSCC-A1C. These results indicated that VDR may be involved in the pathogenesis of SPS rats, thereby providing an alternative preparation to search for optimal therapeutic strategies for PTSD.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Receptores de Calcitriol/metabolismo , Estresse Psicológico/metabolismo , Animais , Western Blotting , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/patologia , Cálcio/metabolismo , Canais de Cálcio Tipo L/genética , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Espaço Intracelular/metabolismo , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Calcitriol/genética , Estresse Psicológico/genética
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