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991.
Increased amino acid availability acutely stimulates protein synthesis partially via activation of mechanistic target of rapamycin complex 1 (mTORC1). Plant-and insect-based protein sources matched for total protein and/or leucine to animal proteins induce a lower postprandial rise in amino acids, but their effects on mTOR activation in muscle are unknown. C57BL/6J mice were gavaged with different protein solutions: whey, a pea–rice protein mix matched for total protein or leucine content to whey, worm protein matched for total protein, or saline. Blood was drawn 30, 60, 105 and 150 min after gavage and muscle samples were harvested 60 min and 150 min after gavage to measure key components of the mTORC1 pathway. Ingestion of plant-based proteins induced a lower rise in blood leucine compared to whey, which coincided with a dampened mTORC1 activation, both acutely and 150 min after administration. Matching total leucine content to whey did not rescue the reduced rise in plasma amino acids, nor the lower increase in mTORC1 compared to whey. Insect protein elicits a similar activation of downstream mTORC1 kinases as plant-based proteins, despite lower postprandial aminoacidemia. The mTORC1 response following ingestion of high-quality plant-based and insect proteins is dampened compared to whey in mouse skeletal muscle. 相似文献
992.
Jian Zhang Ai Zhao Shiyun Lai Qingbin Yuan Xiaojiang Jia Peiyu Wang Yumei Zhang 《Nutrients》2021,13(5)
Our knowledge related to human milk proteins is still limited. The present study determined the changes in multiple human milk proteins during the first six months of lactation, investigated the influencing factors of milk proteins, and explored the impact of milk proteins on infant growth. A total of 105 lactating women and their full-term infants from China were prospectively surveyed in this research. Milk samples were collected at 1–5 days, 8–14 days, 1 month, and 6 months postpartum. Concentrations of total protein and α-lactalbumin were measured in all milk samples, and concentrations of lactoferrin, osteopontin, total casein, β-casein, αs−1 casein, and κ-casein were measured in milk from 51 individuals using ultra performance liquid chromatography coupled with mass spectrometry. The concentration of measured proteins in the milk decreased during the first six months of postpartum (p-trend < 0.001). Maternal age, mode of delivery, maternal education, and income impacted the longitudinal changes in milk proteins (p-interaction < 0.05). Concentrations of αs−1 casein in milk were inversely associated with the weight-for-age Z-scores of the infants (1 m: r −0.29, p 0.038; 6 m: r −0.33, p 0.020). In conclusion, the concentration of proteins in milk decreased over the first six months postpartum, potentially influenced by maternal demographic and delivery factors. Milk protein composition may influence infant weights. 相似文献
993.
Joanna Moro Nadezda Khodorova Daniel Tom Claire Gaudichon Catherine Tardivel Thierry Berton Jean-Charles Martin Dalila Azzout-Marniche Delphine Jouan-Rimbaud Bouveresse 《Nutrients》2021,13(5)
Objective: Dietary intakes must cover protein and essential amino acid (EAA) requirements. For this purpose, different methods have been developed such as the nitrogen balance method, factorial method, or AA tracer studies. However, these methods are either invasive or imprecise, and the Food and Agriculture Organization of the United Nations (FAO, 2013) recommends new methods and, in particular, metabolomics. The aim of this study is to determine total protein/EAA requirement in the plasma and urine of growing rats. Methods: 36 weanling rats were fed with diets containing 3, 5, 8, 12, 15, and 20% protein for 3 weeks. During experimentation, urine was collected using metabolic cages, and blood from the portal vein and vena was taken at the end of the experiment. Metabolomics analyses were performed using LC-MS, and the data were analyzed with a multivariate analysis model, partial least Squares (PLS) regression, and independent component-discriminant analysis (ICDA). Each discriminant metabolite identified by PLS or ICDA was tested by one-way ANOVA to evaluate the effect of diet. Results: PLS and ICDA allowed us to identify discriminating metabolites between different diet groups. Protein deficiency led to an increase in the AA catabolism enzyme systems inducing the production of breakdown metabolites in the plasma and urine. Conclusion: These results indicate that metabolites are specific for the state of EAA deficiency and sufficiency. Some types of biomarkers such as AA degradation metabolites appear to be specific candidates for protein/EAA requirement. 相似文献
994.
Anne Daly Wolfgang Hgler Nicola Crabtree Nick Shaw Sharon Evans Alex Pinto Richard Jackson Catherine Ashmore Júlio C. Rocha Boyd J. Strauss Gisela Wilcox William D. Fraser Jonathan C. Y. Tang Anita MacDonald 《Nutrients》2021,13(6)
In patients with phenylketonuria (PKU), treated by diet therapy only, evidence suggests that areal bone mineral density (BMDa) is within the normal clinical reference range but is below the population norm. Aims: To study longitudinal bone density, mass, and geometry over 36 months in children with PKU taking either amino acid (L-AA) or casein glycomacropeptide substitutes (CGMP-AA) as their main protein source. Methodology: A total of 48 subjects completed the study, 19 subjects in the L-AA group (median age 11.1, range 5–16 years) and 29 subjects in the CGMP-AA group (median age 8.3, range 5–16 years). The CGMP-AA was further divided into two groups, CGMP100 (median age 9.2, range 5–16 years) (n = 13), children taking CGMP-AA only and CGMP50 (median age 7.3, range 5–15 years) (n = 16), children taking a combination of CGMP-AA and L-AA. Dual X-ray absorptiometry (DXA) was measured at enrolment and 36 months, peripheral quantitative computer tomography (pQCT) at 36 months only, and serum blood and urine bone turnover markers (BTM) and blood bone biochemistry at enrolment, 6, 12, and 36 months. Results: No statistically significant differences were found between the three groups for DXA outcome parameters, i.e., BMDa (L2–L4 BMDa g/cm2), bone mineral apparent density (L2–L4 BMAD g/cm3) and total body less head BMDa (TBLH g/cm2). All blood biochemistry markers were within the reference ranges, and BTM showed active bone turnover with a trend for BTM to decrease with increasing age. Conclusions: Bone density was clinically normal, although the median z scores were below the population mean. BTM showed active bone turnover and blood biochemistry was within the reference ranges. There appeared to be no advantage to bone density, mass, or geometry from taking a macropeptide-based protein substitute as compared with L-AAs. 相似文献
995.
目的探讨输出蛋白(XPO)4、丝裂原活化蛋白激酶(MAP2K)4及小脑锌指结构蛋白(ZIC)1在子宫内膜癌(EC)组织中的表达及其对EC患者的预后评估价值。 方法选择2017年6月至2018年6月,无锡市妇幼保健院、复旦大学附属中山医院青浦分院收治的147例EC患者为研究对象。采用免疫组化染色法检测患者EC组织及癌旁正常组织XPO4、MAP2K4、ZIC1表达水平。采用χ2检验,对患者EC组织及癌旁正常组织XPO4、MAP2K4、ZIC1阳性率,以及不同临床病理特征患者EC组织XPO4、MAP2K4、ZIC1阳性率进行比较。采用Two-stage检验,对EC组织XPO4、MAP2K4、ZIC1呈阳性与呈阴性患者的3年总体生存(OS)率进行比较。本研究遵循的程序经过无锡市妇幼保健院、复旦大学附属中山医院青浦分院伦理委员会批准(审批文号:20160803、20160502)。 结果①本组患者EC组织XPO4、MAP2K4阳性率分别为34.7%(51/147)、38.1%(56/147),显著低于癌旁正常组织的66.7%(98/147)与72.8%(107/147),并且差异均有统计学意义(χ2=30.060、35.812,P<0.001)。本组患者EC组织ZIC1阳性率为72.1%(106/147),显著高于癌旁正常组织的40.1%(59/147),并且差异亦有统计学意义(χ2=30.512、P<0.001)。②不同年龄、EC直径及绝经与否患者的EC组织XPO4、MAP2K4、ZIC1阳性率比较,差异均无统计学意义(P>0.05)。不同国际妇产科联盟(FIGO)临床分期、组织病理学分级、子宫肌层侵犯程度及淋巴结转移与否患者EC组织XPO4、MAP2K4、ZIC1阳性率分别比较,差异均有统计学意义(P<0.05)。③本组EC组织XPO4、MAP2K4呈阴性患者的3年OS率分别为42.7%、38.5%,均显著低于XPO4、MAP2K4呈阳性者的68.6%、71.4%,并且差异均有统计学意义(χ2=8.960、P=0.003,χ2=15.077、P<0.001)。EC组织ZIC1呈阳性患者3年OS率为35.8%,显著低于ZIC1呈阴性者的68.3%,并且差异亦有统计学意义(χ2=12.579、P<0.001)。 结论在EC组织中,XPO4、MAP2K4呈低表达,而ZIC1则呈高表达。XPO4、MAP2K4、ZIC1表达水平与患者组织病理学分级、淋巴结转移、FIGO临床分期、子宫肌层侵犯及3年OS率显著相关,其在评估EC患者发病、进展及预后中具有一定价值。 相似文献
996.
目的探讨高迁移率族蛋白B1(HMGB1)多态性和血清表达与肺癌化疗患者肺部感染及其严重程度的关系。方法选择2018年3月-2020年1月商丘市第一人民医院肿瘤内科收治的晚期肺癌化疗患者118例作为研究对象,根据其化疗期间是否发生肺部感染分为感染组(n=57)及非感染组(n=61)。采用聚合酶链式扩增反应(PCR)对两组患者外周血HMGB1 rs1412125(T>C)、HMGB1 rs2249825(C>G)进行基因分型,分析感染组HMGB1不同基因型患者、C-反应蛋白(CRP)、降钙素原(PCT)水平及肺部感染严重程度评分(Pneumonia severity index,PSI)。结果感染组HMGB1 rs1412125位点CC基因型、C等位基因频率, rs2249825位点GG基因型、G等位基因频率均显著高于非感染组(P<0.05);校正性别、年龄等因素后,多元Logistic回归结果显示,HMGB1 rs1412125位点CC基因型、C等位基因,rs2249825位点GG基因型、G等位基因是本地区晚期肺癌化疗患者肺部感染的危险因素;感染组患者HMGB1 rs1412125位点CC型血清HMGB1、CRP、PCT水平及PSI评分均高于TT型及TC型(P<0.05),感染组患者HMGB1 rs2249825位点GG型血清HMGB1、CRP、PCT水平及PSI评分高于CG型及CC型(P<0.05)。结论 HMGB1 rs1412125位点、HMGB1 rs2249825位点多态性与本地区肺癌化疗患者肺部感染易感性及严重程度有关,HMGB1 rs1412125位点CC型、HMGB1 rs2249825位点GG型为易感基因型。 相似文献
997.
目的探讨肺结核抗结核药物致肝损伤患者HMGB1基因多态性。方法选择2016年8月-2019年8月中南大学湘雅医院附属海口医院滨江分院收治的肺结核患者200例,发展成ATDH的患者纳入ATDH组(n=79),未发展成ATDH的患者纳入非ATDH组(n=121),检测HMGB1基因单核苷酸多态性(SNPs)位点多态性,采用Logistic回归分析HMGB1多态性位点与ATDH的关系。结果ATDH组HMGB1基因rs1045411位点GG、GA、AA基因型分布频率和G、A等位基因频率与非ATDH组比较,差异有统计学意义(P<0.05),rs1412125、rs1360485以及rs2249825位点基因型分布和等位基因频率与非ATDH组比较,均无统计学差异;在共显性、显性、隐性模式下,ATDH组HMGB1基因rs1045411位点基因型分布与非ATDH组比较,差异有统计学意义(P<0.05),与GG基因型比较,GA和AA基因型与肺结核易感性有关,在超显性模式下,ATDH组HMGB1基因rs1045411位点基因型分布与非ATDH组比较,无统计学差异,而在超显性、共显性、显性以及隐性模式下,rs1412125、rs1360485以及rs2249825位点基因型分布与非ATDH组比较,均无统计学差异;rs1045411位点基因多态性与ATDH的发生存在相关性,且突变型诱发ATDH可能性更大,而rs1412125、rs1360485、rs2249825位点基因多态性与ATDH发生风险无关。结论HMGB1基因为ATDH的易感基因,其rs1045411位点多态性与ATDH的发生密切相关,其中突变型发生ATDH风险升高。 相似文献
998.
目的 探究整合素β1(integrin β1,ITGβ1)、人γ干扰素诱导蛋白16(interferon - inducible protein 16,IFI16)、转甲状腺素蛋白(transthyretin,TTR)血清水平与妊娠期高血压疾病进展程度关联性及临床表达意义。 方法 选取2018年11月—2020年1月在攀枝花市中心医院住院分娩的妊娠期高血压疾病患者91例为研究组,另随机选取同期正常妊娠孕妇91例为对照组。对比两组血清ITGβ1、IFI16、TTR水平,采用Spearson秩相关分析血清各指标与妊娠期高血压疾病进展程度的相关性,采用受试者工作(receiver operating characteristic,ROC)曲线分析探讨血清各指标对妊娠期高血压疾病患者妊娠结局的预测价值。 结果 研究组血清ITGβ1、IFI16水平高于对照组,血清TTR水平低于对照组(P<0.05);妊娠期高血压疾病进展程度与血清ITGβ1、IFI16水平呈正相关,与血清TTR水平呈负相关(P<0.05);血清ITGβ1>2.38 ng/ml、IFI16>24.39 ng/ml、TTR≤315.08 mg/L联合预测妊娠期高血压疾病患者有无不良妊娠结局的曲线下面积(area under the carve,AUC)为0.861,大于各指标单一预测的AUC(0.782、0.813、0.790),联合预测的敏感度、特异度分别为80.00%、81.82%。 结论 妊娠期高血压疾病患者血清ITGβ1、IFI16表达明显升高,血清TTR表达水平降低,与妊娠期高血压疾病的发生及病情进展程度密切相关,且能辅助临床预测患者妊娠结局。 相似文献
999.
儿童期肥胖增加血脂异常、高血压、高血糖等心血管代谢风险(CMR),并可持续至成人,使代谢性疾病低龄化。近年发现,尿酸、视黄醇结合蛋白4、维生素D、颈围等与肥胖儿童CMR密切相关,可作为CMR的预警指标,为心血管代谢疾病的早期防治提供新靶标。认识预警指标与代谢风险的关系、作用机制和临床意义,有助于早期识别有CMR相关因素的高危人群并进行干预。 相似文献
1000.
《Obesity research & clinical practice》2022,16(2):122-129
BackgroundTo study the effect of WISP1 on lipopolysaccharide (LPS)-induced cell injury in 3T3-L1 adipocytes.MethodLentivirus was transiently transfected into log phase 3T3-L1 adipocytes, which were then treated with LPS at a concentration of 10 μg/mL for 24 h. The cells were divided into the following groups: group A (control, untreated cells); group B (LPS-treated cells); group C (GFP), cells transfected with lentivirus-containing GFP; group D (GFP+LPS), group C treated with LPS;group E (WISP1OE), cells transfected with lentivirus, group F (shNC+LPS), cells transfected with lentivirus-containing nshRNA treated with LPS; group G (shWISP1 +LPS), cells transfected with lentivirus-containing shRNA treated with LPS; group H (WISP1OE+LPS), group E treated with LPS; group I (WISP1OE+LPS+LY294002), group E treated with LPS followed by LY294002 for 24 h.ResultsWISP1 overexpression notably ameliorated cell apoptosis, accompanied with the increased expression of bcl-2, the decreased expressions of bax and cleaved-caspase-3, and promoted the release of inflammatory factors, such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in LPS-treated 3T3-L1 adipocytes. WISP1 knockdown exhibited the opposite results. In addition, WISP1 stimulated Akt phosphorylation and reduced nuclear translocation of Fork head box protein O3 (FoxO3a) in 3T3-L1 adipocytes treated by LPS. The inhibition of the PI3K/Akt signaling pathway diminished the protective effect of WISP1.ConclusionWISP1 prevents 3T3-L1 adipocytes from being injured by LPS by regulating the PI3K/Akt pathway. 相似文献