Uridine diphosphate glucuronosyltransferase 1A1 prevents the progression of liver injury

BACKGROUND Uridine diphosphate glucuronosyltransferase 1A1(UGT1A1)plays a crucial role in metabolizing and detoxifying endogenous and exogenous substances.However,its contribution to the progression of liver damage remains unclear.AIM To determine the role and mechanism of UGT1A1 in liver damage progression.METHODS We investigated the relationship between UGT1A1 expression and liver injury through clinical research.Additionally,the impact and mechanism of UGT1A1 on the progression of liver injury was analyzed through a mouse model study.RESULTS Patients with UGT1A1 gene mutations showed varying degrees of liver damage,while patients with acute-onchronic liver failure(ACLF)exhibited relatively reduced levels of UGT1A1 protein in the liver as compared to patients with chronic hepatitis.This suggests that low UGT1A1 levels may be associated with the progression of liver damage.In mouse models of liver injury induced by carbon tetrachloride(CCl_(4))and concanavalin A(ConA),the hepatic levels of UGT1A1 protein were found to be increased.In mice with lipopolysaccharide or liver steatosis-mediated liver-injury progression,the hepatic protein levels of UGT1A1 were decreased,which is consistent with the observations in patients with ACLF.UGT1A1 knockout exacerbated CCl_(4)-and ConA-induced liver injury,hepatocyte apoptosis and necroptosis in mice,intensified hepatocyte endoplasmic reticulum(ER)stress and oxidative stress,and disrupted lipid metabolism.CONCLUSION UGT1A1 is upregulated as a compensatory response during liver injury,and interference with this upregulation process may worsen liver injury.UGT1A1 reduces ER stress,oxidative stress,and lipid metabolism disorder,thereby mitigating hepatocyte apoptosis and necroptosis.

陶瓷溶出铁、镍离子与Uridine(脲苷)络合物的性能研究

中药传统熬制一般采用陶瓷器皿,因陶瓷具有强度高、化学惰性、热稳定性好、耐腐蚀等优于金属器皿(金属离子过量则有毒,因此不用金属器皿熬药)的性能,且陶瓷器皿中适当缓慢溶出微量的金属离子,与中药的有效化学成分发生络合作用,从而可能增强药效。采用量子化学中的DFT(密度泛函)法,在B3LYP水平上,使用Gauss09程序包研究陶瓷中所含微量Fe离子和Ni离子分别与中药分子中的有效化学成分Uridine(脲苷)的络合体系,得到相应的优化几何结构、激发态、NBO电荷分布、相互作用能等。结果表明:陶瓷器皿中溶出的Fe离子和Ni离子均能与uridine分子有效络合且相互作用能相近,说明络合物均能稳定存在且稳定性相当,增强了中药中有效化学成分的药效。

Potential role of ecto-5'-nucleotidase in morphine-induced uridine release and neurobehavioral changes

OBJECTIVE There is growing evidence that uridine may act as an endogenous neuromodulator with a potential signaling role in the central nervous system in addition to its function in pyrimidine metabolism.We previously found that acute morphine treatment significantly increased uridine release in the dorsal striatum of mice,while the mechanism involved in morphine-induced uridine release and the role of uridine in morphine-induced neurobehavioral changes have not been understood.METHODS Uridine release in the dorsal striatum of mice was assessed by in vivo microdialysis coupled with high performance liquid chromatography(HPLC) after morphine treatment.Western blotting and immunofluorescence were used to evaluate the expression of uridine-related proteins.Morphine-induced neurobehavioral changes were assessed by locomotor activity,behavioral sensitization and conditioned place preference(CPP)test.The expression of NT5E,an extracellular enzyme involved in formation of nucleosides,including uridine,was specifically knocked down in the dorsal striatum of mice using adeno-associated virus(AAV)-mediated short hairpin RNA(shRNA).RESULTS Both acute and chronic morphine administration significantly increased uridine release in the dorsal striatum,and this was associated with upregulation of NT5E but not other uridine-related proteins.Inhibition of NT5E with APCP or shRNA markedly inhibited morphine-induced uridine release in the dorsal striatum and related neurobehavioral changes,including hyperlocomotor activity,behavioral sensitization and CPP.CONCLUSION The present study increases our understanding of the contribution of NT5E in regulating morphine-induced neurobehavioral changes,at least as related to uridine,and suggests that NT5E may be a novel therapeutic target to manage morphine abuse.

No association between cyclooxygenase-2 and uridine diphosphate glucuronosyltransferase 1A6 genetic polymorphisms and colon cancer risk

AIM：To investigate the association of variations in the cyclooxygenase-2 （COX2） and uridine diphosphate glucuronosyltransferase 1A6 （UGTIA6） genes and non-steroidal anti-inflammatory drugs （NSAIDs） use with risk of colon cancer.METHODS： NSAIDs, which are known to reduce the risk of colon cancer, act directly on COX2 and reduce its activity. Epidemiological studies have associated variations in the COX2 gene with colon cancer risk, but others were unable to replicate this finding. Similarly,enzymes in the UGT1A6 gene have been demonstrated to modify the therapeutic effect of NSAIDs on colon adenomas. Polymorphisms in the UGTIA6 gene have been statistically shown to interact with NSAID intake to influence risk of developing colon adenomas, but not colon cancer. Here we examined the association of tagging single nucleotide polymorphisms （SNPs） in the COX2 and UGTIA6 genes, and their interaction with NSAID consumption, on risk of colon cancer in a population of 422 colon cancer cases and 481 population controls.RESULTS： No SNP in either gene was individually statistically significantly associated with colon cancer, nor did they statistically significantly change the protective effect of NSAID consumption in our sample. Like others, we were unable to replicate the association of variants in the COX2 gene with colon cancer risk （P 〉 0.05）,and we did not observe that these variants modify the protective effect of NSAIDs （P 〉 0.05）. We were able to confirm the lack of association of variants in UGT1A6 with colon cancer risk, although further studies will have to be conducted to confirm the association of these variants with colon adenomas.CONCLUSION： Our study does not support a role of COX2 and UGTIA6 genetic variations in the development of colon cancer.

Induction of Recombinant Uridine Phosphorylase and Its Application in Biosynthesis of Pyrimidine Nucleosides

Recombinant Escherichia coli pUDP,which overexpressed uridine phosphorylase（UPase）,was constructed.0.5 mmol·L 1lactose had a similar induction effect as the commonly used inducer IPTG during 2.5-5.5 h of cell growth.The lactose-induced UPase was stable at 50°C.Wet cells of pUDP was used as catalyst to biosynthesize 5-fluorouridine from 30 mmol·L 1uridine and 5-fluorouracil in phosphate buffer（pH 7.0）catalyzed at 50°C for 1.5 h and the yield of 5-fluorouridine was higher than 68%.Under the optimum reaction conditions for production of 5-fluorouridine,5-methyluridine and azauridine were synthesized from uridine by pUDP,the yield was 61.7%and 47.2%respectively.Deoxynucleosides were also synthesized by pUDP,but the yield was only about 20%.

Symptomatic improvement in an acute, non-traumatic spine pain model with a combination of uridine triphosphate, cytidine monophosphate, and hydroxocobalamin

Rationale: In a previously published trial on spinal acute non-traumatic pain, peripheral neuro- regenerative combination of UTP, CMP and hydroxocobalamin presented unexpected analgesicproperties. Objective: To corroborate analgesiceffects of UTP, CMP and hydroxocobalamin combination in a self-paired evolutionary model. Methods: Mean VAS scores from pretreatment, V2 (5th treatment day) and V3 (10th treatment day) were plotted and statistically analyzed (ANOVA) for differences. PFQ scores from pretreatment, V2, and V3 were analyzed using the chisquare test. Results: The difference between V3 and pretreatment mean VAS scores was statistically significant (p < 0.0001). The improvement in PFQ scores throughout the study was found to be statistically significant (p < 0.0001). Conclusion: The combination of UTP, CMP and hydroxocobalamin seems to have analgesic properties in mediumterm use. The complex peripheral neu-roregenerative pharmacodynamics of this combination provides a plausible basis for this finding. Further randomized studies are needed to explore this combination for the indication of neuropathic pain due to spinal structure involvement.

Chemically Modified Uridine Molecules Incorporating Acyl Residues to Enhance Antibacterial and Cytotoxic Activities

A new N-acetylsulfanilylation series of uridine have been synthesized in good yield using direct acylation method and afforded the 5’-O-N-acetylsulfanilyluridine. In order to obtain newer products, the 5’-O-N-acetylsulfanilyluridine derivative was further transformed to a series of 2’,3’-di-O-acyl derivatives containing a wide variety of functionalities in a single molecular framework. The chemical structures of the newly synthesized compounds were confirmed on the basis of their FTIR, 1H-NMR spectroscopy, physicochemical properties and elemental analysis. All the synthesized uridine derivatives were tested for their in vitro antibacterial activity against six human pathogenic bacterial strains and for comparison standard antibiotic Ampicillin was also determined. The study revealed that the selectively acylated deriva-tives 5’-O-N-acetylsulfanilyl-2’,3’-di-O-lauroyluridine and 5’-O-N-acetylsulfanilyl-2’,3’-di-O-pivaloyluridine showed highest inhibition against Staphylococcus aureus and Bacillus cereus, respectively. We also observed that the introduction of hexanoyl, decanoyl, lauroyl, myristoyl and pivaloyl groups, the antibacterial functionality of the compound uridine increases. Another noteworthy observation was that the uridine derivatives were found comparatively more effective against Gram-positive microorganisms than those of Gram-negative microorganisms. In addition, the test chemicals were also tested for cyto-toxicity by brine shrimp lethality bioassay and compounds showed different rate mortality with different concentrations.

Uridine dynamic administration affects the circadian variation of bile acid metabolism in high-fat-diet-fed mice

High-fat diet(HFD)is demonstrated to disturb the bile acid metabolism.The rhythm of bile acid metabolism can also be affected by uridine,whose metabolism exhibits a daily rhythm.However,the mechanism of dynamic uridine administration affecting bile acid during HFD remains unclear.In this study,C57BL/6J mice were fed HFD(the control group;CON)or HFD with oral administration of uridine in the daytime(DUR)and nighttime(NUR)to investigate the mechanism of the effect of uridine on the bile acid.This study showed that the mRNA expression of uridine transporters and circadian clock genes in the jejunum was affected by zeitgeber time(ZT)(P<0.001).Genes related to the metabolism of pyrimidines in the liver showed a high dependence on daily rhythm(P<0.01),and DUR remarkably up-regulated the expression of ribonucleotide reductase regulatory subunit M2(RRM2)(P<0.05)compared to the CON group.Importantly,the mRNA expression of bile acids nuclear receptors,bile acid synthesis,and transporters in the liver showed significantly rhythmically changed(P<0.05),and the expression of cholesterol 7-alpha-hydroxylase(CYP7A1),fibroblast growth factor receptor 4(FGFR4),Na^(+)/taurocholate co transporting polypeptide(NTCP),and bile salt export pump(BSEP)mRNAs of mice with uridine administration increased significantly(P<0.05).The mRNA expression of the transporters of cholesterol and bile acids in the ileum was also affected by ZT(P<0.01)and significantly dependent on uridine administration(P<0.05).The expression of FXR and SHP was significantly affected by ZT and uridine,respectively.In conclusion,dynamic administration of uridine could regulate the rhythm of gene expression of pyrimidine and bile acid metabolism in the liver and ileum of HFD-fed mice,which contributed to the further study of circadian rhythmic physiological and pathological changes of bile acids.

Excess-Electron Attachment and Ionization of Aqueous Uridine Monophosphate Anion

We applied quantum mechanics/classical mechanics simulations to study excess-electron attachment and ionization of uridine monophosphate anion(d UMP-)in explicit aqueous solutions.We calculated vertical electron affinities(VEAs),adiabatic electron affinities(AEAs),vertical detachment energies(VDEs),vertical ionization energies(VIEs),and adiabatic ionization energies(AIEs)of the 40 structures obtained from molecular dynamic trajectory.The excess-electron and hole distributions were analyzed in electron attachment and ionization of aqueous d UMP^(-).The converged mean VEA(-0.31 e V)and AEA(2.13 e V)suggest that excess-electron can easily attach to d UMP^(-).The mean vertical(-0.50 e)and adiabatic(-0.62 e)excess-electron on uracil reveal that main excesselectrons are localized on nucleobases at the most snapshots.The distributions at several special snapshots demonstrate the excess-electron delocalization over nucleobases/ribose or ribose/phosphate group after the structural relaxations of d UMP^(2-)dianion.The VDE value(2.78 e V)indicates that d UMP2-dianion could be very stable.Moreover,the mean VIE is 8.13 eV which is in agreement with the previous calculation using solvation model.The hole distributions on uracil suggest that the nucleobases are easily ionized after the irradiation of high-energy rays.In vertical ionizations,the holes would be delocalized over uracil and ribose at several snapshots.Observing the adiabatic hole distributions,it can be found that electrons on phosphate group and holes on nucleobases can be transferred to ribose at the special snapshots in the structural relaxation of neutral species.

Synthesis and Diastereomeric Analysis of Uridine 2’,3’-Cyclic Phosphite

Uridine 2’,3’-cyclic phosphite has been synthesized and the diastereomers were analysed by 2D NMR technique to assign the configuration

An AM1 Study on the Mechanism of Uridine Phospborolysis

We have cd quantum chemical method tO ho the transition states of uridinephosphorolysis reaction under the neutral condition. Comparing the activation energies ofdifferent reaction modes, we conclude that uridine phosphorolysis takes Place mainlyaccording tO a concerted mechanism. The computational are consistent with somecritical experimental factsss.

尿苷二磷酸葡萄糖促进三角褐指藻岩藻黄素积累的研究

岩藻黄素(Fucoxanthin)是自然界中丰富的类胡萝卜素,为提高微藻中岩藻黄素的含量,本实验主要通过叶绿素荧光参数法、高效液相色谱法等探究了外源添加不同浓度的尿苷二磷酸葡萄糖(UDPG)对三角褐指藻光合作用能力及岩藻黄素含量的影响。研究表明,150μmol/L UDPG显著提高了三角褐指藻的光合作用能力,促进了三角褐指藻中岩藻黄素积累,其含量达到(9.57±0.81)mg/g,比对照组提高了161.76%。此外,硅甲藻黄素、硅藻黄素、β-胡萝卜素、紫黄质、叶绿素a和叶绿素c 2的含量分别比对照组提高了84.31%、79.73%、164.74%、123.04%、358.35%和2260.09%。研究结果表明,外源添加150μmol/L UDPG可显著促进三角褐指藻积累岩藻黄素。

一测多评法测定美洲大蠊药材5种核苷类成分

目的建立高效液相色谱(HPLC)一测多评法同时测定美洲大蠊中尿嘧啶、尿苷、次黄嘌呤、肌苷及鸟苷5种成分的含量。方法采用Agilent ZORBAX SB-Aq色谱柱(250 mm×4.6 mm,5μm);以甲醇-0.01 mol·L^(-1)磷酸二氢钾溶液为流动相,梯度洗脱;流速:1.0 mL·min^(-1);柱温:20℃;检测波长:260 nm;进样量:10μL。计算内参物尿苷与其他成分的相对校正因子(fa/b)。一测多评法测定10批美洲大蠊中5种成分含量,并与外标法比较。结果5种核苷类在各自范围内线性良好(r>0.9995),平均加样回收率97.0%~100.8%。尿嘧啶、次黄嘌呤、肌苷、鸟苷的fa/b分别是0.9080、1.0053、1.9695、1.3034。结论所建立的方法准确稳定,可为美洲大蠊药材及提取物的质量控制提供理论参考。

嘌呤核苷磷酸化酶/嘧啶核苷磷酸化酶共表达及固定化催化合成阿糖核苷

将嘌呤核苷磷酸化酶(PNP)和尿苷磷酸化酶(UP)进行共表达和双酶固定化,提高生物法合成阿糖核苷过程中底物转化率和催化剂稳定性。首先,构建大肠杆菌内源(PNP)和(UP)过表达工程菌,考察工程菌催化不同阿糖核苷之间转化的效率。将PNP和UP双酶固定化,并对固定化双酶进行回收利用,考察重复使用过程中固定化双酶的催化效率。结果表明:工程菌催化阿糖尿苷和腺嘌呤生成阿糖腺苷的反应最高转化率可达93.6%。固定化双酶催化合成阿糖2,6-二氨基嘌呤核苷的最高转化率可达99.8%。重复回收使用固定化双酶19次后对底物的转化率达到60.6%,累计有效催化时长可达684 h。PNP和UP的双酶耦合体系能高效催化阿糖核苷之间的转化,固定化修饰有利于延长酶的使用寿命,为生物法生产核苷类似物提供重要科学参考。

云南地区53例先天性高胆红素血症临床特征及UGT1A1基因多态性分析

目的探讨云南地区53例UGT1A1基因突变所致的先天性高胆红素血症(Gilbert综合征、Crigler-Najjar综合征)的临床特征及UGT1A1基因突变特点。方法选取2017年1月至2022年12月间昆明市儿童医院消化内科53例Gilbert综合征(GS组)、Crigler-NajjarⅡ型综合征(CN-2组)患儿的临床数据、UGT1A1基因突变结果,回顾性分析患儿的临床特征、实验室检查结果和基因多态性。结果少数民族患儿均在2组中发病率较高,CN-2组中女性比例比GS高。肝脏系统方面,CN-2组TBil、IDB水平较GS组更高,差异均有统计学意义(P<0.05),GS组肝脏结构正常,CN-2组有3例患者肝胆结构有异常。肝外系统方面,血液系统、糖代谢无异常,血脂、甲状腺功能代谢有异常,GS组有维生素D不足,CN-2组存在维生素A、D缺乏及维生素E水平下降。2组患儿均存在心脏结构异常,但CN-2组较GS组发病率高。在所有患者中,突变频率最高的为发生在5号外显子上的c.1456T>G(32例,60.37%),其次为c.1091C>T(14例,26.42%)、1号外显子c.211G>A(6例,11.32%)和c.1198A>C(4例,7.55%)。c.1456T>G位点突变在GS组和CN-2组的频率分别为69.23%和57.5%(9例和23例),2组间差异无统计学意义(P>0.05)。2组中,其次突变频率较高的为c.1091C>T(4例和10例),2组间差异无统计学意义(P>0.05)。UGT1A1基因单倍型1、3、4在GS组和CN-2组间的频率差异均有统计学意义(P<0.05)。UGT1A1基因的4种主要突变形式,在性别和不同民族间,差异无统计学意义(P>0.05)。结论GS组和CN-2组在肝脏系统、肝外系统的临床表现存在不同,UGT1A1基因突变频率最高的为发生在5号外显子上的c.1456T>G。

板蓝根注射液特征图谱及其质量相关性研究

建立板蓝根注射液尿苷、鸟苷、(R,S)-告依春、腺苷含量检测方法及指纹图谱研究。采用高效液相色谱法,色谱柱:Eclipse Plus C18柱(4.6 mm×250 mm,5μm),检测波长250 nm,以甲醇(A)-水(B)为流动相,梯度洗脱(0~3 min,95%B;3~20 min,95%B-90%B;20~40 min,90%B~30%B;40~42 min,30%B~95%B;42~50 min,95%B),流速为1.0 mL/min,柱温箱为30℃,进样量10μL。该实验操作简单、快捷,结果准确,适用板蓝根注射液尿苷、鸟苷、(R,S)-告依春、腺苷含量的测定,建立指纹图谱,对板蓝根注射液进行质量评估。

赤芝中腺苷和尿苷HPLC指纹图谱及含量分析

采用指纹图谱对赤芝水溶性成分中的腺苷和尿苷进行检测及含量测定,寻找不同来源孢子粉和子实体的含量变化规律,结果表明,不同来源和处理的灵芝粉和孢子粉在指纹图谱上有明显差异。赤芝菌盖中尿苷含量为0.072~0.849 mg·g^(-1),菌柄中尿苷含量为0.056~0.302 mg·g^(-1),破壁孢子粉中尿苷含量为0.032~0.089 mg·g^(-1);赤芝菌盖中腺苷含量为0.019~0.118 mg·g^(-1),菌柄中腺苷含量为0.005~0.024 mg·g^(-1),破壁孢子粉中腺苷含量为0.024~0.107 mg·g^(-1);同品种不同潮次采收的未破壁孢子粉主要成分含量无较大差异;同一品种的破壁孢子粉和未破壁孢子粉之间也无明显差异,但同一品种不同批次的赤芝中腺苷和尿苷含量差异显著。因此,可利用高效液相色谱法指纹图谱在8.5~20.0 min的区域内破壁孢子粉只有一个峰鉴别出破壁孢子粉,利用尿苷和腺苷的含量鉴别孢子粉中是否含有灵芝粉。

26例遗传性球形红细胞增多症的临床及基因诊断

目的:遗传性球形红细胞增多症(hereditary spherocytosis,HS)是最常见的遗传性红细胞膜缺陷病,主要表现为贫血、黄疸、脾大。由于部分患者临床表现不典型、家族史阴性,加上传统的实验室检查敏感性和特异性均较低,常导致漏诊、误诊。目前已明确ANK1、SPTB、SPTA1、SLC4A1和EPB42基因突变可引起其对应的编码蛋白质缺失,进而导致红细胞膜缺陷。本研究旨在分析HS基因诊断的可行性和临床应用价值。方法:回顾性收集2018年1月至2021年9月中南大学湘雅二医院血液内科收治的26例中国湖南HS患者的资料,分析其临床表现和实验室检测结果。应用二代测序(next-generation sequencing,NGS)结合Sanger测序,检测HS致病基因突变和胆红素代谢调控关键酶尿苷二磷酸葡萄糖醛酸转移酶1家族多肽A1(uridine diphosphate-glucuronosyl transferase 1 family polypeptide A1,UGT1A1)变异。根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)发布的《序列变异解释的标准和指南》进行致病基因变异判读。分析不同基因变异类型患者的临床特征,并对其临床诊断和基因诊断进行对比分析。结果:在26例HS患者中,贫血23例、黄疸25例、脾大24例、胆石症14例;16例有家族史,10例无家族史;25例HS致病基因突变检测结果为阳性,1例阴性。19个家系共检出18个HS致病基因杂合变异,其中14个为致病性变异,1个可能致病性变异,3个意义未明变异。SPTB突变(12个)和ANK1突变(4个)最多。变异类型以无义突变为主(9个)。SPTB突变组与ANK1突变组相比,外周血红细胞参数及溶血指标的差异均无统计学意义(均P>0.05)。ANK1突变组切脾率高于SPTB突变组,差异有统计学意义(χ^(2)=6.970,P=0.014)。不同突变类型(无义突变、移码突变、剪接位点突变及错义突变)组间外周血红细胞参数及溶血指标差异亦均无统计学意义(均P>0.05)。临床确诊的18例患者中,17例与基因诊断一致;临床疑诊患者8例,均经HS致病基因突变检测确诊。24例HS患者行UGT1A1变异检测,5例患者携带UGT1A1变异导致酶活性降低,19例酶活性正常。酶活性降低组较酶活性正常组的总胆红素(total bilirubin,TBIL)水平高,差异具有统计学意义(U=22,P=0.038)。结论:大多数HS患者有贫血、黄疸和脾大,常合并胆石症。中国湖南HS致病基因突变以SPTB和ANK1突变最常见,基因型与临床表型无明显相关性。基因诊断与临床诊断高度一致。UGT1A1酶活性降低可导致HS患者黄疸程度加重。临床联合基因诊断有利于HS的快速、精准诊断;而UGT1A1酶活性相关基因变异检测对HS黄疸评估有重要意义。

猪UGT 1A1酶基因的克隆、表达及其对呕吐毒素特异性降解的作用

为了在Sf9昆虫细胞中表达猪尿苷二磷酸葡萄糖醛酸转移酶(UGT)1A1蛋白并对其进行功能鉴定。首先,合成密码子优化的UGT 1A1基因,克隆到载体pFastBacⅠ中,构建杆状病毒重组转移载体,然后导入DH10Bac中,获得重组的穿梭质粒,再转染Sf9细胞得到重组杆状病毒,采用Western blotting方法鉴定重组后UGT 1A1蛋白的表达;对镍柱亲和层析纯化获得目的蛋白酶的动力学参数及其对呕吐毒素(DON)的代谢进行检测。结果表明:pFastBac-UGT 1A1质粒被成功构建,导入感受态细胞DH10Bac中获得重组穿梭质粒Bacmid-UGT 1A1,再转染昆虫细胞Sf9获得重组Bacmid-UGT 1A1蛋白,能够与多组氨酸标签单抗发生特异性反应。优化目的蛋白表达,并对其体外代谢DON进行了酶学性质和动力学参数的研究。本研究通过基因克隆、表达和代谢产物的分析等技术手段获得具有较好的生物活性且纯化的Bacmid-UGT 1A1蛋白,为揭示DON在肝脏中的代谢途径、代谢产物和关键调控因子提供参考。