The effect of protein oxidation on the formation of advanced glycation end products after chicken myofibrillar protein glycation

Investigation that protein oxidation to the formation of advanced glycation end products(AGEs)after chicken myofibrillar protein glycation is limited.Models of protein oxidation induced by different concentrations of hydroxyl radicals(·OH)were developed after the chicken myofibrillar protein mild glycation(MPG).Results exhibited that levels of AGEs and surface hydrophobicity(H_(0))steadily increased with the a ddition of h ydrogen peroxide(H_(2)O_(2))concentration.However,levels of s ulfhydryl group,free amino group,and particle size gradually decreased with the H_(2)O_(2)concentration.The protein carbonyl value increased in H_(2)O_(2)concentration until 10 mmol/L.Pearson's correlation indicated that MPG structure modification(unfolding and degradation)induced by protein oxidation were significantly positively correlated with AGEs concentration(P<0.05).Finally,a mechanism was proposed to hypothesize t he effect of protein oxidation on the formation of AGEs under MPG conditions.

Diet with high content of advanced glycation end products induces oxidative stress damage and systemic inflammation in experimental mice: protective effect of peanut skin procyanidins

Non-enzymatic glycation reaction in food can produce diet-derived advanced glycation end products(dAGEs),which have potential health risks.Thus,it is of great significance to find efficient substances to improve the negative effects induced by dAGEs on human health.This study investigated the intervening effects of peanut skin procyanidins(PSP)on the dAGEs-induced oxidative stress and systemic inflammation in experimental mice model.Results showed that the accumulation of AGEs in serum,liver,and kidney was significantly increased after mice were fed dAGEs(P<0.05).The expression of advanced glycation product receptor(RAGE)was also significantly increased in liver and kidney(P<0.05).PSP could not only effectively reduce the accumulation of AGEs in serum,liver and kidney of mice,but also reduce the expression of RAGE in liver and kidney of mice.And the levels of pro-inflammatory cytokines interleukin-6(IL-6),tumor necrosis factor(TNF-α),and IL-1βin serum of mice were significantly decreased(P<0.05),while the levels of antiinflammatory factor IL-10 were increased,and the inflammatory injury in mice was improved.In addition,the levels of superoxide dismutase(SOD),glutathione(GSH),catalase(CAT)in liver and kidney of mice were increased(P<0.05),and the level of malondialdehyde(MDA)was decreased(P<0.05),which enhanced the antioxidant capacity of mice in vivo,and improved the oxidative damage of liver and kidney.Molecular docking technique was used to confirm that the parent compound of procyanidins and its main metabolites,such as 3-hydroxyphenylacetic acid,could interact with RAGE,which might inhibit the activation of nuclear transcription factor(NF-κB),and ultimately reduce oxidative stress and inflammation in mice.

Advanced glycation end products:Key mediator and therapeutic target of cardiovascular complications in diabetes

The incidence of type 2 diabetes mellitus is growing in epidemic proportions and has become one of the most critical public health concerns.Cardiovascular complications associated with diabetes are the leading cause of morbidity and mortality.The cardiovascular diseases that accompany diabetes include angina,myocardial infarction,stroke,peripheral artery disease,and congestive heart failure.Among the various risk factors generated secondary to hyperglycemic situations,advanced glycation end products(AGEs)are one of the important targets for future diagnosis and prevention of diabetes.In the last decade,AGEs have drawn a lot of attention due to their involvement in diabetic pathophysiology.AGEs can be derived exogenously and endogenously through various pathways.These are a nonhomogeneous,chemically diverse group of compounds formed nonenzymatically by condensation between carbonyl groups of reducing sugars and free amino groups of protein,lipids,and nucleic acid.AGEs mediate their pathological effects at the cellular and extracellular levels by multiple pathways.At the cellular level,they activate signaling cascades via the receptor for AGEs and initiate a complex series of intracellular signaling resulting in reactive oxygen species generation,inflammation,cellular proliferation,and fibrosis that may possibly exacerbate the damaging effects on cardiac functions in diabetics.AGEs also cause covalent modifications and cross-linking of serum and extracellular matrix proteins;altering their structure,stability,and functions.Early diagnosis of diabetes may prevent its progression to complications and decrease its associated comorbidities.In the present review,we recapitulate the role of AGEs as a crucial mediator of hyperglycemia-mediated detrimental effects in diabetes-associated complications.Furthermore,this review presents an overview of future perspectives for new therapeutic interventions to ameliorate cardiovascular complications in diabetes.

Role of Protein Kinase C in Advanced Glycation End Products-induced Epithelial-Mesenchymal Transition in Renal Proximal Tubular Epithelial Cells

The role of protein kinase C （PKC） activation in advanced glycation end products （AGEs）-induced epithelial-mesenchymal transition in renal proximal tubular epithelial cells was investigated. HKC cells were divided into three groups： normal group, AGE-BSA group （100 mg/L AGE-BSA） and AGE-BSA＋PKC inhibitor （10 μmol/L chelerythrine chloride） group. PKC activity was measured by PKC assay kit. The expression of Vimentin, and phosphorylated β-catenin was detected by using Western blotting, and the content of TGF-β1 was examined by ELISA method. The intracellular disposition of Vimentin was observed by fluorescence microscopy. As compared with normal group, PKC activity was increased significantly in AGE-BSA group. The expression of Vimentin, phosphorylated β-catenin, and TGF-β1 was enhanced significantly in AGE-BSA group. The expression of Vimentin, phosphorylated β-catenin, and TGF-β1 was significantly blocked by chelerythrine chloride. High expression of Vimentin, phosphorylated β-catenin, and TGF-β1 induced by AGE-BSA may be mediated via the activation of PKC signal transduction pathway.

Effect of Italian Sour Cherry (<i>Prunus cerasus</i>L.) on the Formation of Advanced Glycation End Products and Lipid Peroxidation

Sweet and sour cherries contain several polyphenols that possess antioxidant and anti-inflammatory properties. Aim of this study was to investigate the effect of the maturity stage on phenol content and biological properties of extract of a local Morello-type of sour cherry (Prunus cerasus?L.), “visciola”. The study of total phenol content and total antioxidant potential was associated with the evaluation of the antioxidant property of extracts using a copper catalyzed human low density lipoproteins (LDL) oxidation as experimental model. Moreover, using albumin glycated by methylglyoxal, we evaluated the anti-glycation effect of fruit extract. The results demonstrated that fully ripened fruits exert higher antioxidant and anti-glycation properties when compared with partially ripened fruits. Information about the health-promoting components of “visciola” could lead to a better understanding and an increased consumption of these, including its use as functional food.

Glyoxal induced advanced glycation end products formation in chicken meat emulsion instead of oxidation

Advanced glycation end products(AGE) are potential harmful substances formed in the advanced Maillard reaction and increasingly investigated in muscle foods. However, the contribution of oxidation to the AGE formation is controversial. Moreover, reports on glyoxal(GO) induced AGE formation in chicken meat emulsion(CME) are limited. Thus, the effects of GO on emulsifying properties, rheological behavior and AGE formation in CME were investigated. Our findings exhibited that levels of Nε-carboxymethyllysine(CML) and Nε-carboxyethyllysine(CEL) were associated with lipid oxidation but not significantly(P > 0.05). Levels of AGE peaked when GO concentration ranged from 5 mmol/L(CML) to 10 mmol/L(CEL). The droplets’ aggregation associated with the disulfide bond when the concentration of GO was at 0.5–30 mmol/L while non-disulfide bond association occurred at 30–50 mmol/L GO concentration. In conclusion, compared to the effect of oxidation, GO exhibited the main role in the AGE formation of CME. This study will provide theoretical significance for further understanding and controlling the formation of AGE in CME.

Injury of cortical neurons is caused by the advanced glycation end products-mediated pathway

Advanced glycation end products lead to cell apoptosis, and cause cell death by increasing endoplasmic reticulum stress. Advanced glycation end products alone may also directly cause damage to tissues and cells, but the precise mechanism remains unknown. This study used primary cultures of rat cerebral cortex neurons, and treated cells with different concentrations of glycation end products （50, 100, 200, 400 mg/L）, and with an antibody for the receptor of advanced glycation end products before and after treatment with advanced glycation end products. The results showed that with increasing concentrations of glycation end products, free radical content increased in neurons, and the number of apoptotic cells increased in a dose-dependent manner. Before and after treatment of advanced glycation end products, the addition of the antibody against advanced glycation end-products markedly reduced hydroxyl free radicals, malondialdehyde levels, and inhibited cell apoptosis. This result indicated that the antibody for receptor of advanced glycation end-products in neurons from the rat cerebral cortex can reduce glycation end product-induced oxidative stress damage by suppressing glycation end product receptors. Overall, our study confirms that the advanced glycation end products-advanced glycation end products receptor pathway may be the main signaling pathway leading to neuronal damage.

Advanced glycation end products induce neural tube defects through elevating oxidative stress in mice

Our previous study showed an association between advanced glycation end products （AGEs） and neural tube defects （NTDs）. To understand the molecular mechanisms underlying the effect of AGEs on neural tube development, C57BL/6 female mice were fed for 4 weeks with com- mercial food containing 3% advanced glycation end product bovine serum albumin （AGE-BSA） or 3% bovine serum albumin （BSA） as a control. After mating mice, oxidative stress markers including malondialdehyde and H202 were measured at embryonic day 7.5 （E7.5） of ges- tation, and the level of intracellular reactive oxygen species （ROS） in embryonic cells was determined at E8.5. In addition to evaluating NTDs, an enzyme-linked immunosorbent assay was used to determine the effect of embryonic protein administration on the N-（carboxymethyl） lysine reactivity of acid and carboxyethyl lysine antibodies at E10.5. The results showed a remarkable increase in the incidence of NTDs at El0.5 in embryos of mice fed with AGE-BSA （no hyperglycemia） compared with control mice. Moreover, embryonic protein administration resulted in a noticeable increase in the reactivity of N-（carboxymethyl） lysine and N（ε）-（carboxyethyl） lysine antibodies. Malondialdehyde and H2O2 levels in embryonic cells were increased at E7.5, followed by increased intracellular ROS levels at E8.5. Vitamin E supplementation could partially recover these phenomena. Collectively, these results suggest that AGE-BSA could induce NTDs in the absence of hyperglycemia by an underlying mechanism that is at least partially associated with its capacity to increase embryonic oxidative stress levels.

Effect of thioltransferase on oxidative stress induced by high glucose and advanced glycation end products in human lens epithelial cells

AIM:To study the effect of thioltransferase(TTase)on oxidative stress in human lens epithelial cells(HLECs)induced by high glucose and advanced glycation end products(AGEs).METHODS:HLECs were treated with 35.5 mmol/L glucose or 1.5 mg/mL AGEs modified bovine serum albumin(AGEs-BSA)as the experimental groups,respectively.Cells were collected at the time point of 1,2,3,and 4 d.The TTase activity were measured accordingly.TTase mRNA levels were detected by quantitative reverse transcription polymerase chain response(qRT-RCR)and its protein level was detected by Western blot.The siRNA was used to knock down the expression of TTase.The activity of catalase(CAT)and superoxide dismutase(SOD),the content of reactive oxygen species(ROS)and the ratio of oxidized glutathione/total glutathione(GSSG/T-GSH)were assessed in different groups,respectively.RESULTS:The level of TTase mRNA gradually increased and reached the top at 2 d,then it decreased to the normal level at 4 d,and the TTase activity increased from 2 to 3 d in both high glucose and AGEs-BSA groups.The TTase expression elevated from 2 d in high glucose group,and it began to rise from 3 d in AGEs-BSA group.The activity of CAT and SOD showed a decrease and the content of ROS and the ratio of GSSG/T-GSH showed an increase in high glucose and AGEs-BSA group.These biochemical alterations were more prominent in the groups with TTase siRNA.CONCLUSION:High glucose and AGEs can increase ROS content in HLECs;therefore,it induces oxidative stress.This may result in the decreased GSH and increased GSSG content,impaired activity of SOD and CAT.The up-regulated TTase likely provides oxidation damage repair induced by high glucose and AGEs in the early stage.

Increased expression of receptor for advanced glycation end-products worsens focal brain ischemia in diabetic rats

A rat model of diabetes mellitus was induced by a high fat diet, followed by focal brain ischemia induced using the thread method after 0.5 month. Immunohistochemistry showed that expression of receptor for advanced glycation end-products was higher in the ischemic cortex of diabetic rats compared with non-diabetic rats with brain ischemia. Western blot assay revealed increased phosphorylated c-Jun N-terminal kinase expression, and unchanged phosphorylated extracellular signal-regulated protein kinase protein expression in the ischemic cortex of diabetic rats compared with non-diabetic rats with brain ischemia. Additionally, phosphorylated p38 mitogen-activated protein kinase protein was not detected in any rats in the two groups. Severity of limb hemiplegia was worse in diabetic rats with brain ischemia compared with ischemia alone rats. The results suggest that increased expression of receptor for advanced glycation end-products can further activate the c-Jun N-terminal kinase pathway in mitogen-activated protein kinase, thereby worsening brain injury associated with focal brain ischemia in diabetic rats.

Advanced Oxidation Protein Products Regulate the Pharmacokinetics of Aloe-emodin,Emodin,Rhein,and Chrysophanol in Chronic Kidney Disease Rats

Background:As accelerators and products of the progression of chronic kidney disease(CKD),advanced oxidation protein products(AOPPs)affect the function of the liver.Huang Gan granules(HGGs)are commonly used to prevent the progression of CKD,but the pharmacokinetics of aloe-emodin,emodin,rhein,and chrysophanol in HGGs in CKD remain unknown.Objective:To investigate the influence and its molecular mechanism of AOPPs on the in vivo pharmacokinetics of aloe-emodin,emodin,rhein,and chrysophanol in HGGs.Methods:We constructed 5/6 nephrectomised(5/6 nx),adenine-induced(adenine)and AOPP-treated rat models.After oral administration of HGG,the concentrations of aloe-emodin,emodin,rhein,and chrysophanol in the plasma samples were detected by high-performance liquid chromatography(HPLC),and their pharmacokinetics were analysed with the PKSolver software.The plasma concentrations of IL-6 and TNF-αare detected by enzyme linked immunosorbent assay(ELISA).The RT-PCR was performed in the HepG2 cells to explore the effect of TNF-αand IL-6 on the mRNA expression of CYP1A2 and CYP3A4.Result:The results showed that the method was suitable for the quantification of four anthraquinones in plasma and excreta samples with satisfactory linear(R R^(2)>0.9931),precision(<9.4%)and accuracy(±10%).In 5/6 nx,adenine and AOPPs-treated rats,the concentrations of TNF-αand IL-6 were increased.In 5/6 nx and adenine rats,the pharmacokinetic parameters(t_(1/2),MRT_(0-∞)and AUC_(0-∞))of aloe-emodin,emodin,rhein,and chryso-phanol were,respectively,significantly increased and correlated with the concentration of AOPPs.In AOPPs-treated rats,the concentration of AOPPs was significantly increased and the pharmacokinetic parameters of four anthraquinones were also increased.Conclusion:In summary,inflammatory cytokine production may be one of the important causes in AOPPs’regulat-ing the pharmacokinetic of aloe-emodin,emodin,rhein,and chrysophanol in the CKD rats.Studies of aloe-emodin,emodin,rhein,and chrysophanol in CKD facilitate the appropriate prescription of HGGs in the clinical.

非酒精性脂肪性肝炎患者血清Nrf2、AOPP水平与血脂、肝纤维化的关系

目的探讨非酒精性脂肪性肝炎(NASH)患者血清核因子E2相关因子2(Nrf2)、晚期氧化蛋白产物(AOPP)水平与血脂、肝纤维化的关系。方法选择重庆医科大学附属璧山医院收治的104例NASH患者作为研究组,另选90例体检健康者作为对照组。检测并比较各组血清Nrf2、AOPP水平,采用Pearson或Spearman相关分析NASH患者血清Nrf2、AOPP水平与血脂、肝纤维化的关系,采用受试者工作特征(ROC)曲线评估血清Nrf2、AOPP水平对NASH的诊断价值。结果研究组甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、Nrf2、AOPP水平均高于对照组(P<0.05),高密度脂蛋白胆固醇(HDL-C)水平明显低于对照组(P<0.05)。重度组血清Nrf2、AOPP水平高于中度组、轻度组(P<0.05),中度组血清Nrf2、AOPP水平高于轻度组(P<0.05)。相关分析结果显示,NASH患者血清Nrf2、AOPP水平与TG、TC、LDL-C、肝纤维化程度均呈正相关(P<0.05),与HDL-C呈负相关(P<0.05)。血清Nrf2诊断NASH的曲线下面积(AUC)为0.830(95%CI 0.780~0.880),血清AOPP诊断NASH的AUC为0.866(95%CI 0.816~0.916),二者联合诊断NASH的AUC为0.925(95%CI 0.875~0.975)。结论NASH患者血清Nrf2、AOPP水平均升高,且二者水平与血脂、肝纤维化程度均存在密切关系,有望作为诊断NASH发生的有效指标。

电针对肝郁脾虚型抑郁症大鼠HMGB1/RAGE/TLR4通路及小胶质细胞活化的影响

目的:探究电针对肝郁脾虚型抑郁症大鼠高迁移率族蛋白盒1/晚期糖基化终产物/toll样受体4(HMGB1/RAGE/TLR4)通路及小胶质细胞活化的影响。方法:将大鼠随机分为对照组、模型组、电针组及HMGB1激活剂组,除对照组外均构建肝郁脾虚型抑郁症大鼠模型。观测大鼠体重及行为学表现;采用HE染色法观察大鼠海马组织病理变化;采用免疫组化检测大鼠海马组织中钙接头蛋白1(Iba-1)、一氧化氮合酶(iNOS)的表达情况;采用蛋白免疫印迹(Western blotting)检测海马组织中HMGB1/RAGE/TLR4信号传导通路相关蛋白HMGB1、RAGE、TLR4的表达水平。结果:相较于对照组,模型组大鼠长期动作行为缓慢、脱毛、毛发粗糙、凌乱无光泽,排泄存在水样便,大鼠海马区神经细胞出现明显结构损伤,且大鼠体重及在旷场箱内运动的总路程减少(P<0.05),而在旷箱中央停留时间、休息时间以及海马组织中Iba-1、iNOS、HMGB1、RAGE和TLR4表达升高,差异有统计学意义(均P<0.05)。相较于模型组,电针组大鼠精神状态有所好转,海马区神经细胞损伤程度减轻,细胞形态良好且排列逐渐趋于有序,大鼠体重、在旷场箱内运动总路程提高,差异有统计学意义(均P<0.05)。结论:电针能够抑制肝郁脾虚型抑郁症大鼠小胶质细胞活化,其作用机制可能与抑制HMGB1/RAGE/TLR4通路有关。

结肠癌病人血清S100钙结合蛋白A12、可溶性晚期糖基化终产物受体水平与肠道菌群失调及化疗效果的关系

目的探讨结肠癌病人血清S100钙结合蛋白A12(S100A12)、可溶性晚期糖基化终产物受体(sRAGE)水平与肠道菌群失调及化疗效果的相关性。方法选择2020年12月至2021年12月黄河水利委员会黄河中心医院收治的116例中、晚期结肠癌病人作为结肠癌组,另选取在该院同期健康体检人员120例作为对照组。采用酶联免疫吸附测定(ELISA)检测血清S100A12、sRAGE水平,检测病人肠道菌群,并对病人化疗后进行随访,Pearson法分析结肠癌病人血清S100A12、sRAGE水平与菌群失调相关性,受试者操作特征曲线(ROC曲线)分析化疗前血清S100A12、sRAGE水平对结肠癌化疗效果的诊断价值。结果与对照组比较,结肠癌组病人化疗前血清S100A12、sRAGE水平显著升高(P<0.05)。与化疗前菌群正常组[(265.34±45.78)μg/L、(381.54±36.75)ng/L]比较,菌群失调Ⅰ度组[(301.52±56.95)μg/L、(440.63±48.71)ng/L]、菌群失调Ⅱ度组[(339.29±52.35)μg/L、(432.75±49.20)ng/L]病人血清S100A12、sRAGE水平显著升高(P<0.05);与菌群失调Ⅰ度组比较,菌群失调Ⅱ度组病人血清S100A12、sRAGE水平显著升高(P<0.05)。相关性分析显示,结肠癌病人血清S100A12、sRAGE水平与大肠杆菌、粪肠球菌数量呈正相关(P<0.05),与双歧杆菌、乳酸杆菌数量呈负相关(P<0.05)。与化疗前比较,结肠癌病人化疗后血清S100A12、sRAGE水平显著降低(P<0.05);与化疗缓解组[(272.33±55.36)μg/L、(403.24±40.54)ng/L]比较,化疗无效组[(330.09±42.64)μg/L、(482.85±43.61)ng/L]病人化疗前血清S100A12、sRAGE水平显著较高(P<0.05)。血清S100A12、sRAGE联合诊断结肠癌化疗无效的曲线下面积(AUC)为0.91[95%CI:(0.84,0.96),P<0.001],灵敏度为86.05%,特异度为80.82%。结论结肠癌病人血清S100A12、sRAGE升高,与肠道菌群失调及化疗效果有关,对化疗疗效评估与预后评价有一定指导意义。

血清RAGE、HMGB1水平与重症肺炎急性呼吸窘迫综合征发病及IFN-γ/IL-4变化的关系

目的探究血清晚期糖基化终产物受体(RAGE)、高迁移率族蛋白B1(high mobility group protein B1,HMGB1)水平与重症肺炎(SP)急性呼吸窘迫综合征(ARDS)发病及γ-干扰素(IFN-γ)/白细胞介素4(IL-4)变化的关系。方法前瞻性选取2020年3月至2022年2月我院收治的100例SP患儿为研究对象,根据患儿是否发生继发性ARDS将患儿分为ARDS组(n=56)和对照组(n=44),收集患儿一般资料,采集外周血以酶联免疫吸附法进行RAGE、HMGB1、IFN-γ和IL-4表达水平检测,采用多因素logistic回归分析SP患儿继发ARDS的影响因素,采用Pearson相关性分析其与IFN-γ/IL-4的相关性,并采用受试者工作曲线(ROC)分析RAGE、HMGB1表达对SP患儿继发ARDS的预测价值。结果两组SP患儿性别、年龄、体温以及发病季节之间无显著差异,ARDS组致病菌种类多于对照组,PaO_(2)/FiO_(2)和APS评分、血清RAGE、HMGB1、IFN-γ和IL-4表达水平以及IFN-γ/IL-4比值均高于对照组(P<0.05)。经多因素logistic回归分析可知,致病菌种类、PaO_(2)/FiO_(2)、RAGE、HMGB1表达、IFN-γ、IL-4和IFN-γ/IL-4均为SP患儿继发ARDS的影响因素。经Pearson相关检验,SP患儿血清RAGE、HMGB1表达水平与IFN-γ、IL-4和IFN-γ/IL-4均呈正相关(P<0.05)。经ROC曲线分析可得,血清RAGE、HMGB1水平预测SP患儿发生ARDS的AUC分别为0.707和0.750,灵敏度分别为73.2%、64.3%,特异度分别为68.2%、77.3%,两者联合预测的AUC为0.848,灵敏度和特异度分别为80.4%和81.8%。结论SP继发ARDS患儿血清中RAGE、HMGB1表达水平较高,与IFN-γ/IL-4呈正相关,监测患儿血清RAGE、HMGB1表达对SP患儿继发ARDS的风险有一定的预测价值。

芦丁调控miR-155和HMGB1/RAGE通路对糖尿病视网膜病变大鼠炎性反应的影响

目的:探讨芦丁对糖尿病视网膜病变大鼠炎性反应的影响及其机制。方法:采用腹腔注射链脲佐菌素的方法制备糖尿病大鼠模型,将造模成功的大鼠随机分为模型组(0.9%氯化钠溶液灌胃)和芦丁低、中、高剂量组[分别以50、100、150 mg/(kg·d)芦丁灌胃],并取正常大鼠作为对照组(0.9%氯化钠溶液灌胃),每组20只,持续给药12周后,比较各组大鼠视网膜组织中伊凡斯兰渗透量、神经节细胞凋亡和微小RNA(miR)-155、高迁移率族蛋白1(HMGB1)、晚期糖基化终产物受体(RAGE)mRNA表达水平,以及炎症因子水平。结果:对照组、模型组和芦丁低、中、高剂量组中伊凡斯兰渗透量分别为(1.61±0.31)μg/g、(12.84±1.24)μg/g、(9.85±0.62)μg/g、(6.80±0.53)μg/g、(2.87±0.51)μg/g,神经节细胞凋亡指数分别为(1.09±0.45)%、(30.96±2.50)%、(24.65±2.48)%、(18.61±1.41)%、(8.36±0.54)%,miR-155表达水平分别为(0.38±0.03)、(1.92±0.15)、(1.55±0.12)、(1.09±0.10)、(0.55±0.05),HMGB1 mRNA表达水平分别为(0.26±0.03)、(0.77±0.05)、(0.68±0.04)、(0.57±0.04)、(0.34±0.03),RAGE mRNA表达水平分别为(0.18±0.02)、(0.67±0.04)、(0.58±0.03)、(0.45±0.03)、(0.23±0.02)。模型组和对照组比较,伊凡斯兰渗透量、凋亡指数和miR-155、HMGB1、RAGE mRNA水平均升高(均P<0.05);芦丁低、中、高剂量组中上述指标呈剂量依赖性降低(均P<0.05)。模型组、对照组与芦丁低、中、高剂量组,芦丁各组的炎症因子水平低于模型组(均P<0.05)。结论:芦丁可保护糖尿病大鼠视网膜损伤,延缓视网膜炎症效应,其作用机制可能与抑制miR-155和HMGB1/RAGE通路有关。

穿心莲内酯调节HMGB1/RAGE信号通路对糖尿病周围神经病变大鼠坐骨神经功能损伤的影响

目的探讨穿心莲内酯调节高迁移率族蛋白B1(HMGB1)/晚期糖基化终产物受体(RAGE)信号通路对糖尿病周围神经病变(DPN)大鼠坐骨神经功能损伤的影响。方法将84只大鼠随机分为对照组(生理盐水)、DPN组(生理盐水)、穿心莲内酯低剂量组(0.833 mg/kg)、穿心莲内酯高剂量组(3.332 mg/kg)、硫辛酸组(阳性对照,0.1 g/kg)、重组大鼠HMGB1蛋白(rHMGB1,8μg/kg)组、穿心莲内酯高剂量+rHMGB1组,每组12只。除对照组外,其余各组大鼠均采用高糖高脂饲料喂养联合腹腔注射链脲佐菌素的方式构建DPN模型。造模成功24 h后,进行给药处理,每天1次,持续8周。给药结束后,检测大鼠空腹血糖、机械痛阈值、热痛阈值、坐骨神经传导速度的变化;观察大鼠坐骨神经病理变化;检测大鼠坐骨神经中超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量;检测大鼠坐骨神经中HMGB1、RAGE蛋白表达水平和核因子κB p65(NF-κB p65)蛋白磷酸化水平。结果与对照组比较,DPN组大鼠坐骨神经病理损伤严重,空腹血糖、热痛阈值、MDA含量及HMGB1、RAGE蛋白表达水平和NF-κB p65蛋白磷酸化水平均显著升高(P<0.05),机械痛阈值、感觉神经传导速度、运动神经传导速度、SOD活性显著降低/减慢(P<0.05);与DPN组比较,穿心莲内酯低、高剂量组和硫辛酸组大鼠上述指标均显著改善(P<0.05),rHMGB1组对应指标变化趋势与上述3个给药组相反(P<0.05);并且,rHMGB1可减弱高剂量穿心莲内酯对DPN大鼠血糖的降低作用及坐骨神经氧化应激损伤的改善作用(P<0.05)。结论穿心莲内酯可能通过抑制HMGB1/RAGE信号通路来降低血糖、抑制氧化应激,进而改善DPN大鼠坐骨神经损伤。

UV/H_(2)O_(2)体系对水中卤代苯醌类消毒副产物的降解路径与产物毒性预测评价

卤代苯醌是一种新型的饮用水消毒副产物,选用两种代表性的卤代苯醌--2,6-二氯苯醌(2,6-DCBQ)和2,6-二溴苯醌(2,6-DBBQ)为目标污染物,探究UV/H_(2)O_(2)体系对2,6-DCBQ、2,6-DBBQ的降解路径与产物毒性。Gaussian模型及其热力学反应计算结果表明,HO·倾向于先通过争夺DCBQ和DBBQ分子苯环上C-H键的氢原子发生取代反应,然后通过C-Cl键脱卤而继续降解;ECOSAR模型评估结果显示,DCBQ和DBBQ降解产物的急性和慢性毒性普遍低于其母体化合物,说明UV/H_(2)O_(2)体系对于卤代苯醌类消毒副产物能有效降解且减毒。

香辛料提取物改善水产品蛋白质过氧化研究进展

水产品保存和加工过程中发生的蛋白质过氧化对产品营养价值、感官质量、结构特性和蛋白质功能特性等都产生较大的影响。天然香辛料提取物不仅能赋予水产品风味,还能在水产品加工和贮藏过程中表现出良好的抗氧化特性。本文阐述了蛋白质氧化的分子机制、香辛料提取物主要成分及其延缓蛋白过氧化的作用机制,总结了其在改善水产品蛋白氧化方面的应用研究,以期为扩展香辛料提取物应用途径、优化水产品加工工艺提供理论支持。

高级氧化技术去除水中药物和个人护理品的研究进展

随着人们生活水平的提高,药物和个人护理品(PPCPs)的用量不断增加,常规水处理工艺中对PPCPs的去除效果不佳,导致其在水体中频繁被检出,对生态环境和人体健康产生潜在风险。因此,迫切需要更先进的水处理技术去除PPCPs。介绍了含有PPCPs的水质特征,回顾了传统的水处理方法优缺点,重点介绍了高级氧化法去除水中PPCPs的最新动态和研究进展,总结高级氧化法降解PPCPs存在的问题并对未来的发展提出展望。