Uncoupling protein 2 deficiency of non-cancerous tissues inhibits the progression of pancreatic cancer in mice

Background: Pancreatic ductal adenocarcinoma(PDAC) is a disease of the elderly mostly because its development from preneoplastic lesions depends on the accumulation of gene mutations and epigenetic alterations over time. How aging of non-cancerous tissues of the host affects tumor progression, however, remains largely unknown. Methods: We took advantage of a model of accelerated aging, uncoupling protein 2-deficient( Ucp2 knockout, Ucp2 KO) mice, to investigate the growth of orthotopically transplanted Ucp2 wild-type(WT) PDAC cells(cell lines Panc02 and 6606PDA) in vivo and to study strain-dependent differences of the PDAC microenvironment. Results: Measurements of tumor weights and quantification of proliferating cells indicated a significant growth advantage of Panc02 and 6606PDA cells in WT mice compared to Ucp2 KO mice. In tumors in the knockout strain, higher levels of interferon-γ m RNA despite similar numbers of tumor-infiltrating T cells were observed. 6606PDA cells triggered a stronger stromal reaction in Ucp2 KO mice than in WT animals. Accordingly, pancreatic stellate cells from Ucp2 KO mice proliferated at a higher rate than cells of the WT strain when they were incubated with conditioned media from PDAC cells. Conclusions: Ucp2 modulates PDAC microenvironment in a way that favors tumor progression and implicates an altered stromal response as one of the underlying mechanisms.

VEGFR2、miR-21、UCP1及UCP3在非小细胞肺癌组织中表达及与其预后的相关性分析

目的分析血管内皮细胞生长因子受体2(VEGFR2)、微小RNA-21(miR-21)、解偶联蛋白1(UCP1)、解偶联蛋白3(UCP3)在非小细胞肺癌(NSCLC)组织内的表达及与其预后的相关性。方法选取98例NSCLC患者,术中取其癌组织与癌旁正常组织,检测VEGFR2、miR-21、UCP1及UCP3表达;分析VEGFR2、miR-21、UCP1及UCP3表达与其临床病理特征的关系;随访1年,分析VEGFR2、miR-21、UCP1及UCP3表达与患者生存率的关系。结果癌组织内的VEGFR2、UCP1阳性表达率及miR-21相对表达量高于癌旁正常组织,UCP3阳性表达率低于癌旁正常组织,差异有统计学意义(P<0.05);VEGFR2、miR-21、UCP1及UCP3表达与淋巴结转移、临床分期、分化程度有关(P<0.05);VEGFR2、UCP1阳性表达及miR-21高表达患者的1年生存率分别低于VEGFR2、UCP1阴性表达及miR-21低表达患者,UCP3阳性表达患者的1年生存率高于UCP3阴性表达者,差异有统计学意义(P<0.05)。结论VEGFR2、miR-21、UCP1及UCP3在NSCLC癌组织内呈异常表达,与患者的预后具有紧密联系。

Effect of Target-directed Regulation of Uncoupling Protein-2 Gene Expression on Ischemia-reperfusion Injury of Hepatocytes

The effect of target-directed regulation of the uncoupling protein-2 （UCP-2） gene expression on the ischemia-reperfusion injury of hepatocytes under different conditions was investigated. The expression plasmid and RNAi plasmid targeting UCP-2 gene were constructed and trans- fected into normal hepatocytes and fatty liver cells, respectively. The expression of UCP-2 mRNA was detected by real time PCR. The cells were divided into normal cell group （NCG）, group of normal cells transfected with empty vector （EVNCG）, group of normal cells transfected with expression plasmid （EPNCG）, fatty liver cell group （FCG） and group of fatty liver cells transfected with RNAi plasmid （RPFCG）. The ischemia-reperfusion model in vitro was established. One, 6, 12 and 24 h after reperfusion, Annexin V/PI flow cytometry was used to measure cell necrosis rate, apoptosis rate and survival rate. Simultaneously, the intracellular ATP, ROS and MDA levels were determined. The re- sults showed that 1, 6, 12 and 24 h after ischemia-reperfusion, the intracellular ROS, MDA and ATP levels and cell survival rate in EPNCG were significantly lower, and cell necrosis rate significantly higher than in NCG and EVNCG, but there was no significant difference in apoptosis rate among NCG, EVNCG and EPNCG （P〉005）. Six, 12 and 24 h after reperfusion there was no significant dif- ference in ROS, MDA levels and apoptosis rate between FCG and RPFCG （P〉0.05）, but the ATP level and survival rate of cells in RPFCG were higher than in FCG （P〈0.05）. It was concluded that down-regulation of the UCP-2 gene expression in steatotic hepatocytes could alleviate the ische- mia-reperfusion injury of liver cells.

Uncoupling protein 2 regulates glucagon-like peptide-1 secretion in L-cells

AIM:To investigate whether uncoupling protein 2(UCP2) affects oleic acid-induced secretion of glucagonlike peptide-1(GLP-1) in L-cells.METHODS:mRNA and protein expression of UCP2 were analyzed in human NCI-H716 cells,which serve as a model for enteroendocrine L-cells,by quantitative reverse transcription-polymerase chain reaction and Western blotting before and after treatment with oleic acid.Localization of UCP2 and GLP-1 in NCI-H716 cells was assessed by immunofluorescence labeling.NCI-H716 cells were transiently transfected with a small interfering RNA(siRNA) that targets UCP2(siUCP2) or with a nonspecific siRNA using Lipofectamine 2000.The concentrations of bioactive GLP-1 in the medium were measured by enzyme linked immunosorbent assay.RESULTS:Both GLP-1 and UCP2 granules were expressed mainly in the cytoplasm of NCI-H716 cells.NCI-H716 cells that secreted GLP-1 also expressed UCP2.Time-course experiments revealed that release of GLP-1 from NCI-H716 cells into the medium reached a maximum at 120 min and remained stable until at least 180 min after treatment with oleic acid(the level of GLP-1 increased about 2.3-fold as compared with the level of GLP-1 in the control cells,P < 0.05).In an experiment to determine dose dependence,stimulation of NCI-H716 cells with ≤ 8 mmol oleic acid led to a concentration-dependent release of GLP-1 into the medium;10 mmol oleic acid diminished the release of GLP-1.Furthermore,GLP-1 secretion induced by oleic acid from NCI-H716 cells that were transfected with siUCP2 decreased to 41.8%,as compared with NCI-H716 cells that were transfected with a non-specific siRNA(P < 0.01).CONCLUSION:UCP2 affected GLP-1 secretion induced by oleic acid.UCP2 plays an important role in L-cell secretion that is induced by free fatty acids.

Mitochondrial uncoupling protein 2 expression in colon cancer and its clinical significance

AIM: To detect the expression of mitochondrial uncoupling protein 2 (UCP2) in colon cancer and analyze the relation between UCP2 expression and clinical pathological features of colon cancer.METHODS: Fifteen colon tissue samples and 15 its adjacent tissue samples were obtained from colon cancer patients during surgical interventions. UCP2 expression was detected with immunohistochemical method in 10 normal controls, 10 hyperplastic polyp patients, 20 tubular adenoma patients and 78 colon cancer patients. Patients with rectal cancer were excluded. Quantitative reverse transcription polymerase chain reaction and Western blotting were used to detect UCP2 expressions in colon cancer tissue samples and its adjacent tissue samples. Relation between UCP2 expression and clinical pathological features of colon cancer was also analyzed. RESULTS: The UCP2 mRNA expression level was fourfold higher in colon cancer tissue samples than in its adjacent tissue samples. The UCP2 protein expression level was three-fold higher in colon cancer tissue samples than in its adjacent normal tissue samples. The UCP2 was mainly expressed in cytoplasm. The UCP2 was not expressed in normal colon mucosa. Strong positive staining for UCP2 with a diffuse distribution pattern was identified throughout the mucosa in colon cancer tissue samples with a positive expression rate of 85.9%. The UCP2 expression level was higher in colon cancer tissue samples at clinical stages Ⅲ and Ⅳ than in those at stageⅠ+ Ⅱ. Univariate analysis showed that the high UCP2 expression level was significantly correlated to colon cancer metastasis (hazard ratio = 4.321, confidence interval = 0.035-0.682, P = 0.046). CONCLUSION: UCP2 is highly expressed in human colon cancer tissue and may be involved in colon cancer metastasis.

Mitochondrial uncoupling protein 2 and pancreatic cancer:A new potential target therapy

Overall 5-years survival of pancreatic cancer patients is nearly 5%,making this cancer type one of the most lethal neoplasia.Furthermore,the incidence rate of pancreatic cancer has a growing trend that determines a constant increase in the number of deceases caused by this pathology.The poor prognosis of pancreatic cancer is mainly caused by delayed diagnosis,early metastasis of tumor,and resistance to almost all tested cytotoxic drugs.In this respect,the identification of novel potential targets for new and efficient therapies should be strongly encouraged in order to improve the clinical management of pancreatic cancer.Some studies have shown that the mitochondrial uncoupling protein 2(UCP2) is over-expressed in pancreatic cancer as compared to adjacent normal tissues.In addition,recent discoveries established a key role of UCP2 in protecting cancer cells from an excessive production of mitochondrial superoxide ions and in the promotion of cancer cell metabolic reprogramming,including aerobic glycolysis stimulation,promotion of cancer progression.These observations together with the demonstration that UCP2 repression can synergize with standard chemotherapy to inhibit pancreatic cancer cell growth provide the molecular rationale to consider UCP2 as a potential therapeutic target for pancreatic cancer.In this editorial,recent advances describing the relationship between cancer development and mitochondrial UCP2 activity are critically provided.

Decreased uncoupling protein 2 expression in aging retinal pigment epithelial cells

AIM: To analyze the expression of uncoupling protein 2(UCP2) in retinal pigment epithelium(RPE) cells at the different human age, further explore the possible new target of RPE cells protection.METHODS: Adult retinal pigment epithelial-19(ARPE-19) cells and the primary RPE cells at the different age(9-20 y,50-55 y, 60-70 y, >70 y) were cultured and harvested. The expression of UCP2 in these cells was detected by reverse transcription-polymerase chain reaction(RT-PCR), Western blot and confocal microscopy.RESULTS: Cells from the donors more than 60 y are larger and more fibroblastic in appearance compared to ARPE-19 cells and those primary cultures obtained from the younger individuals by using phase-contrast micrographs. Results of RT-PCR, Western blot and confocal microscopy all showed that UCP2 was highly expressed in ARPE-19 cells and in the younger primary cultured human RPE cells at the age of 9-20 y and 50-55 y, whereas lower expression of UCP2 was measured in the older primary cultured human RPE cells at the age more than 60 y.CONCLUSION: Expression of UCP2 gene is decreased in aged RPE cells, promoting the lower ability of anti-oxidation in these cells. It is indicated that UCP2 gene might be a new target for protecting the cells from oxidative stress damage.

Uncoupling protein 2 deficiency reduces proliferative capacity of murine pancreatic stellate cells

BACKGROUND： Uncoupling protein 2 （UCP2） has been suggested to inhibit mitochondrial production of reactive oxygen species （ROS） by decreasing the mitochondrial membrane potential. Experimental acute pancreatitis is associated with increased UCP2 expression, whereas UCP2 deficiency retards regeneration of aged mice from acute pancreatitis. Here, we have addressed biological and molecular functions of UCP2 in pancreatic stellate cells （PSCs）, which are involved in pancreatic wound repair and fibrogenesis. METHODS： PSCs were isolated from 12 months old （aged） UCP2^-/- mice and animals of the wild-type （WT） strain C57BL/6. Proliferation and cell death were assessed by em- ploying trypan blue staining and a 5-bromo-2＇-deoxyuridine incorporation assay. Intracellular fat droplets were visualized by oil red O staining. Levels of mRNA were determined by RT-PCR, while protein expression was analyzed by immunoblotting and immunofluorescence analysis. Intracellular ROS levels were measured with 2＇,7＇-dichlorofluorescin diacetate. Expression of senescence-associated β-galactosidase （SA β-Gal） was used as a surrogate marker of cellular senescence. RESULTS： PSCs derived from UCP2^-/- mice proliferated at a lower rate than cells from WT mice. In agreement with this observation, the UCP2 inhibitor genipin displayed dose- dependent inhibitory effects on WT PSC growth. Interestingly, ROS levels in PSCs did not differ between the two strains, and PSCs derived from UCP2^-/- mice did not senesce faster than those from corresponding WT cells. PSCs from UCP2^-/- mice and WT animals were also indistinguishable with respect to the activation-dependent loss of intracellular fat droplets, expression of the activation marker α-smooth muscle actin, type I collagen and the autocrine/paracrine mediators interleukin-6 and transforming growth factor-I~ 1. CONCLUSIONS： A reduced proliferative capacity of PSC from aged UCP2^-/- mice may contribute to the retarded regeneration after acute pancreatitis. Apart from their slower growth, PSC of UCP2^-/- mice displayed no functional abnormalities. The antifibrotic potential of UCP2 inhibitors deserves further attention.

Uncoupling protein 2 regulates myocardial apoptosis via the diabetogenic action of streptozotocin

Objective: Determine the role of uncoupling protein 2 (UCP2) in the myocardial apoptosis of diabetic mellitus(DM). Methods: DM animal models were induced by streptozotocinon (STZ) on UCP2 knock-out mice (UCP2KO) and wild-type mice (WT), which were reared for 7 and 28 days after successful modeling, respectively. The expressions of relative protein for myocardial apoptosis, pro-caspase-9, were investigated using western blot. However, the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) was used to explain apoptosis at the DNA level. Results: Image analysis showed that the expression of pro-caspase-9 protein levels increased slightly in UCP-/- + DM-7-day group comparing with DM-7-day group (P > 0.05). The expression of pro-caspase-9 protein levels increased significantly (P < 0.05)in UCP-/- + DM-28-day group comparing with DM-28-day group. TUNEL analysis indicated that UCP2 reduced the number of apoptotic myocytes in the DM-28-day group by 70% in comparison to DM-7-day group by 30% (P < 0.05). Conclusion UCP2 may be one of the most important factors that contribute to the myocardial apoptosis of DM.

急性缺血性脑卒中患者血清解偶联蛋白2水平与病情严重程度及预后的相关性

目的 探讨解偶联蛋白2(UCP2)与急性缺血性脑卒中(AIS)患者病情严重程度和预后的相关性。方法 选取2020年1月—2022年1月成都市第六人民医院收治的180例AIS患者,根据患者神经功能缺损评估情况,将其分为轻度组57例、中度组89例、重度组34例,所有患者治疗90 d后,根据Rankin量表(mRS)评分将患者评为预后良好组115例和预后不良组65例。酶联免疫吸附法(ELISA)测定所有患者血清中UCP2的含量,并使用受试者工作特征(ROC)曲线预测血清UCP2的水平对AIS患者预后不良的价值;AIS患者预后的影响因素采用Logistic回归分析。结果 轻、中、重度组患者血清UCP2水平依次升高,差异具有统计学意义(P <0.05)。不明原因及其他原因脑卒中、大动脉粥样硬化型脑卒中、心源性脑卒中和小动脉闭塞型脑卒中UCP2水平比较,差异有统计学意义(P<0.05)。AIS患者梗死面积评分为(3.76±0.75)cm^(2),梗死面积≥4 cm^(2)患者血清UCP2水平高于梗死面积<4 cm^(2)患者,差异具有统计学意义(P<0.05)。预后不良组患者血清UCP2水平高于预后良好组,差异具有统计学意义(P<0.05)。UCP2、入院时NIHSS评分、发病到住院时间均是患者发生预后不良的影响因素(P<0.05)。UCP2水平预测AIS患者预后不良的曲线下面积(AUC)为0.847,截断值为5.398 mg/mL,特异性、敏感度分别为79.1%、81.5%,约登指数为0.606。结论 AIS患者血清UCP2水平显著升高,与疾病严重程度密切相关,且对患者预后具有良好的预测价值。

银杏叶提取物通过UCP2/SIRT3通路改善大鼠脑缺血-再灌注损伤

目的:研究银杏叶提取物(EGb761)能否通过线粒体解偶联蛋白2(UCP2)/去乙酰化酶3(SIRT3)通路改善大鼠脑缺血再灌注(CIRI)损伤。方法:雄性SD大鼠分成以下四组:假手术组(sham)、脑缺血再灌注(CIRI)损伤组(CIRI)、银杏叶提取物组(EGb761)和UCP2抑制剂组(EGb761+Genipin)。对EGb761组和EGb761+Genipin组每天尾静脉注射10 mg/kg EGb761注射液,sham组和CIRI组给予尾静脉注射等剂量生理盐水,连续7 d;在第5~7 d,同时对EGb761+Genipin组每天灌胃50 mg/kg Genipin生理盐水溶液。末次给药次日,通过大脑左侧中动脉闭塞法(MCAO)构建大鼠脑CIRI模型。记录各组大鼠Longa神经功能评分和体重变化,取鼠脑制成石蜡切片,通过HE和尼氏染色并观察脑皮质损伤区病理变化;通过免疫组织化学技术检测脑皮质损伤区UCP2、SIRT3及天冬氨酸蛋白半胱氨酸酶3(caspase-3)的表达;收集动脉血,测定血清中总超氧化物歧化酶(SOD)活力和丙二醛(MDA)浓度。结果:与sham组比较,CIRI组大鼠神经功能评分上升(P<0.01),再灌注后体重减轻(P<0.01),脑组织病理损伤加重,UCP2、SIRT3表达减少,caspase-3表达增加(P<0.01),血清SOD活力下降,MDA浓度上升(P<0.01);与CIRI组比较,EGb761组大鼠神经功能评分下降(P<0.01),再灌注后体重增加(P<0.01),脑组织病理损伤减轻,UCP2、SIRT3表达增加,caspase-3表达减少(P<0.01),血清SOD活力增高,MDA浓度下降(P<0.01);与EGb761组比较,EGb761+Genipin组大鼠神经功能评分增加(P<0.05),再灌注后体重减轻(P<0.05),脑组织病理损伤较严重,UCP2、SIRT3表达减少,caspase-3表达增加(P<0.05),血清SOD活力下降,MDA浓度上升(P<0.01)。结论:EGb761可通过调控UCP2/SIRT3通路改善大鼠脑CIRI损伤。

过表达解偶联蛋白2抑制氧化应激减轻糖尿病小鼠心肌缺血再灌注损伤

目的:探讨过表达解偶联蛋白2(UCP2)减轻糖尿病小鼠心肌缺血再灌注损伤(IRI)的机制。方法:60只8周龄C57BL小鼠高脂喂养6周后,注射链脲佐菌素建立小鼠糖尿病模型,采用随机数字表法分为5组,假手术组(Sham组)、缺血再灌注组(I/R组)、UCP2抑制剂组(Genipin组)、空载9型腺相关病毒(AAV9-NC)组(AN组)和携带UCP2基因的AAV9组(AU组),每组12只。Sham组仅切开皮肤后缝合,其余4组开胸结扎冠状动脉左前降支,缺血60 min后松开结扎线结,再灌注120 min建立IRI模型。酶联免疫吸附试验检测血清肌钙蛋白I(cTnI)、丙二醛(MDA)、超氧化物歧化酶(SOD)水平,流式细胞仪观察活性氧(ROS)的产生情况,透射电镜观察线粒体超微结构的变化,Western blot检测UCP2的表达水平,超声心动图评估心功能。结果:与Sham组相比,I/R组、Genipin组、AN组及AU组cTnI、MDA水平明显升高,SOD水平明显下降,ROS产生增多,线粒体结构紊乱,每搏输出量(SV)、射血分数(EF)、左室短轴缩短率(FS)明显降低(P<0.05)。与I/R组相比,Genipin组cTnI、MDA水平明显升高,SOD水平明显下降,ROS产生增多,心肌结构严重受损,线粒体明显肿胀,SV、EF、FS明显降低(P<0.05)。与I/R组相比,AU组cTnI、MDA水平明显降低,SOD水平明显升高,ROS产生减少,心肌结构明显改善,线粒体肿胀减轻,SV、EF、FS的明显升高(P<0.05);AN组与I/R组c TnI、ROS、MDA、SOD、SV、EF、FS的差异无统计学意义,心肌组织和线粒体损伤程度相似。与Sham组相比,I/R组UCP2表达水平明显增加(P<0.05)。与I/R组相比,Genipin组UCP2表达水平明显降低,AU组UCP2表达水平明显增加(P<0.05),AN组与I/R组UCP2表达水平的差异无统计学意义(P>0.05)。结论:过表达的UCP2通过抑制ROS产生,降低氧化应激水平,改善糖尿病小鼠心肌IRI。

Development of a Rapid Multi-residue Assay for Detecting β-lactams Using Penicillin Binding Protein 2x

Objective To develop a rapid multi-residue assay for detecting 16 demanded by the European Union （EU）. Methods A recombinant penicillin-binding protein （PBP） 2x＊ from Streptococcus pneumoniae R6 was expressed in vitro and six β-1actams were conjugated to HRP by four methods. A rapid multi-residue assay for β-1actams was established with PBP2x＊ and HRP-conjugate. Results PBP2x＊ was expressed and purified successfully and the ideal HRP-conjugate was identified. The multi-residue assay was developed. After optimization, penicillin G, ampicillin, amoxicillin, cloxacillin, dicloxacillin, oxacillin, nafcillin, cephalexin, ceftiofur, cefalonium, cefquinome, cefazolin, cefoperazone, cephacetrile, and cephapirin can be detected at levels below MRL in milk with simple pretreatment. Conclusion This assay developed can detect all 16 β-1actams demanded by the European Union （EU）. The whole procedure takes only 45 min and can detect 42 samples and the standards with duplicate analysis.

Inhibition of DNA-dependent Protein Kinase Catalytic Subunit by Small Molecule Inhibitor NU7026 Sensitizes Human Leukemic K562 Cells to Benzene Metabolite-induced Apoptosis

Benzene is an established leukotoxin and leukemogen in humans. We have previously re- ported that exposure of workers to benzene and to benzene metabolite hydroquinone in cultured cells induced DNA-dependent protein kinase catalytic subunit （DNA-PKcs） to mediate the cellular response to DNA double strand break （DSB） caused by DNA-damaging metabolites. In this study, we used a new, small molecule, a selective inhibitor of DNA-PKcs, 2-（morpholin-4-yl）-benzo[h]chomen-4-one （NU7026）, as a probe to analyze the molecular events and pathways in hydroquinone-induced DNA DSB repair and apoptosis. Inhibition of DNA-PKcs by NU7026 markedly potentiated the apoptotic and growth inhibitory effects of hydroquinone in proerythroid leukemic K562 cells in a dose-dependent manner. Treatment with NU7026 did not alter the production of reactive oxygen species and oxidative stress by hydroquinone but repressed the protein level of DNA-PKcs and blocked the induction of the kinase mRNA and protein expression by hydroquinone. Moreover, hydroquinone increased the phos- phorylation of Akt to activate Akt, whereas co-treatment with NU7026 prevented the activation of Akt by hydroquinone. Lastly, hydroquinone and NU7026 exhibited synergistic effects on promoting apop- tosis by increasing the protein levels of pro-apoptotic proteins Bax and caspase-3 but decreasing the protein expression of anti-apoptotic protein Bcl-2. Taken together, the findings reveal a central role of DNA-PKcs in hydroquinone-induced hematotoxicity in which it coordinates DNA DSB repair, cell cycle progression, and apoptosis to regulate the response to hydroquinone-induced DNA damage.

EXPRESSIONS OF P_(53), PROLIFERATING CELL NUCLEAR ANITIGEN,BCL-2 PROTEIN AND THEIR SIGNIFICANCE IN SALIVARY ADENOID CYSTIC CARCINOMA

Objective To study the effects of P53, PCNA, Bc1-2 protein and their relationship in salivary adenoid cystic carclnoma(SACC). Methods These protelns were examlned by lmmunohistochemistry. Results overexpressions of Ps, and PCNA were revealed in ACC samples, they were higher than those in (polymorphous adenomas) PA, but expression of Bc1-2 protein was not different between ACC and PA. In 3 subtypes of ACC, expressions of 3 proteins were different. Conciusion Mutations of P53, Bc1-2 may be involed in the occurrence of SACC, expression of PCNA and mutation of P53 may coexist in the development of the SACC.

解偶联蛋白-2在大鼠非酒精性脂肪肝中的表达

目的:探讨解偶联蛋白-2(uncoupling protein 2,UCP2) 在大鼠非酒精性脂肪肝发生中的作用．方法:Wistar大鼠64只,随机分为高脂饮食诱导脂肪肝组和正常对照组,分别于2,4,8,12 wk用免疫组织化学和Western blot技术检测肝组织中UCP2表达变化,生化检测大鼠血清甘油三酯(TG)、游离脂肪酸(FAA)和丙氨酸氨基转移酶(ALT)含量．结果:大鼠非酒精性脂肪形成过程中UCP2阳性细胞数和表达强度逐渐增加,所有动物肝组织均出现不同程度的肝细胞脂肪变性,并逐渐加重．2,4,8,12 wk血清TG(0．78±0．05,0．85±0．10,1．16±0．10,1．39±0．07 mmol/L)、FAA(371．3±13．7,439．2±14．1,486．3±13．6, 636．7±20．3 μmol／L)和ALT(630．1±41．7,713．5±75．0, 925．2±105．0,1 090．2±65．0 nkat／L)含量较对照组增高,其中TG、FAA 4,8,12 wk均有显著性(P<0．05或 P<0．01),ALT 8,12 wk有显著性(P<0．01)．结论:随着非酒精性脂肪的形成和程度加重,UCP2表达逐渐增强,其介导的酶活性显著增高,启动脂质过氧化反应,促进脂肪肝的形成和发展．

胃癌组织高迁移率族蛋白A2与基质金属蛋白酶-9表达与肿瘤侵袭转移的关系及预后意义

目的探讨胃癌组织中高迁移率族蛋白A2(HMGA2)及基质金属蛋白酶-9(MMP-9)表达与肿瘤侵袭和转移能力的关系及预后意义。方法采用免疫组化法(SP法)检测93例胃癌组织、30例正常胃黏膜组织中HMGA2、MMP-9的表达;收集患者临床病历资料,并进行随访。结果 HGMA2蛋白在胃癌组织中阳性表达率分别为明显高于正常胃黏膜(P<0.01);MMP-9蛋白在胃癌组织中阳性表达率明显高于正常胃黏膜(P<0.01)。HMGA2与MMP-9在胃癌组织中的蛋白阳性表达均与胃癌组织的肿瘤浸润深度、肿瘤分化程度、淋巴结转移、TNM分期有关(P<0.05);与患者的性别、年龄、肿瘤直径无关(P>0.05)。相关性分析发现,HMGA2与MMP-9在胃癌组织中的表达情况呈正相关(r=0.317,P<0.01)。经Kaplan-Meier生存分析显示,HMGA2、MMP-9蛋白表达阳性患者的生存率均低于表达阴性患者(P<0.01)。结论 HMGA2、MMP-9与胃癌浸润和转移有关,两者表达具有相互协同作用,对胃癌的侵袭和转移起重要的促进作用。HMGA2、MMP-9是影响预后的危险因素,可能成为胃癌治疗的新靶点。

解偶联蛋白-2在肠缺血预适应大鼠心肌中的表达

目的:探讨肠缺血预适应(iIPC)对心肌的保护作用以及心肌线粒体解偶联蛋白-2(UCP2)在iIPC心肌保护中的作用。方法:结扎肠系膜上动脉(SMA)制作iIPC大鼠动物模型,对模型大鼠进行心肌持续缺血-再灌注(IR),评价心肌损伤程度,并采用RT-PCR方法、计算机凝胶成像分析心肌UCP2的相对含量。以未结扎SMA的心肌持续缺血-再灌注大鼠为IR对照组,假手术大鼠为空白对照组。结果:①IR对照组大鼠心肌细胞超微结构损伤程度明显超过空白对照组,而iIPC组在iIPC后的0和24 h均轻于IR对照组。②与IR对照组大鼠心肌中UCP2mRNA水平比较,iIPC 0、6、12、24和48 h组均明显升高(P<0.01);iIPC后UCP2 mRNA水平呈双相变化,0 h心肌UCP2水平最高,6 h后下降,24 h再次升高,此后逐渐回落。结论:iIPC能对心肌IR产生保护作用,预适应大鼠心肌UCP2的表达明显升高,提示UCP2可能参与iIPC对心肌的保护作用。

禁食及胰岛素水平对大鼠解偶联蛋白-1、2、3基因表达的影响

为探讨禁食和胰岛素对解偶联蛋白 - 1、2、3基因 (UCP1 ,2 ,3)表达的影响 ,应用 RT- PCR方法观察了在不同禁食时间和应用胰岛素条件下大鼠白色脂肪组织、棕色脂肪组织和骨骼肌中 UCP1 ,2 ,3m RNA水平的变化 .UCP1基因只在大鼠棕色脂肪组织中表达 .UCP2 ,3基因在三种组织中均有表达 ,在白色脂肪组织中以 UCP2表达为主 ;在骨骼肌中以 UCP3表达为主 .过夜禁食使棕色脂肪组织 UCP1 ,3m RNA水平明显下降 (P<0 .0 1 ) ;UCP2 m RNA水平在三种组织中均呈上升反应 ,以白色脂肪组织中表现最为明显 (P<0 .0 5) ;而对白色脂肪组织和骨骼肌中 UCP3基因表达无明显影响 .禁食时间延长至 48h,除棕色脂肪组织中 UCP2 ,3基因有明显下降外 ,各组织中UCPs基因表达基本调节至正常或高于对照组水平 .胰岛素对 UCPs基因表达水平有一定的上调作用 ,这一作用对棕色脂肪组织 UCPs各基因及骨骼肌中 UCP3基因表现得尤为明显 (P<0 .0 5) .大鼠 UCPs基因表达有一定的组织特异性 ;禁食时间对三种组织中 UCPs各成员基因表达的影响有时相上的区别 ;胰岛素可以调 UCPs各成员基因的表达 .结果反映了 UCPs各成员在能量代谢调节上的不同作用 ,这为理解膳食 -产热与体重调节的关系 。

二甲双胍对2型糖尿病患者血浆ET-1和血清hs-CRP、TNF2水平的影响

目的探讨了二甲双胍对DM2T2DM患者血浆ET-1和血清HS-CRP、TNF2水平的影响。方法应用放射免疫分析法和免疫比浊法对33例T2DM患者进行了血浆ET-1和血清HS-CRP、TNF2水平检测,并与35名正常健康人做比较。结果 T2DM患者在治疗前血浆ET-1和血清HS-CRP.TNF2水平均非常显著地高于正常人组(P<0.01)经二甲双胍治疗了3个月后,血浆ET-1和血清HS-CRP、TNF2水平与正常人比较无显著性差异(P>0.05)且ET-1水平与HS-CRP、TNF2水平成正相关(R=0.618 4、0.594 8 P<0.01)。结论二甲双胍具有改善血管内皮功能的作用。