赖氨酸铜对仔猪生产性能及十二指肠、胰脏脂肪酶活性的影响

试验选用 2 1日龄纯种大白仔猪 70头 ,分为A、B、C、D、E 5组 ,A组饲喂基础日粮 (含铜 15mg/kg) ,B、C、D组在基础日粮中添加 5 0、10 0、2 0 0mg/kg赖氨酸铜来源的Cu ,E组在基础日粮中添加 2 0 0mg/kg硫酸铜来源的Cu ,试验期4 2d .结果表明 :日粮添加不同水平的Cu可提高仔猪的日增质量 ,其中C、E两组与A组差异显著 (P <0 0 5 ) ,C组与D、E组差异不显著 (P >0 0 5 ) .与A组比校 ,E组十二指肠内容物脂肪酶活性显著提高 (P <0 0 5 ) .B、C、D组十二指肠、胰脏脂肪酶活性有提高趋势 ,但差异不显著 (P >0 0 5 ) .

脂联素影响体外培养肝细胞乙醛氧化酶1表达的研究

目的研究脂联素(APN)对饱和脂肪酸(SFA)孵育HepG2细胞及HL-7701肝细胞乙醛氧化酶1(AOX1)分泌的影响,探讨APN对非酒精性脂肪肝脏病变(NAFLD)的治疗效果及机制。方法用100μmol/LSFA孵育细胞得到脂肪性HepG2细胞及HL-7701细胞,同时设立细胞对照组(未经100μmol/L SFA孵育)。然后采用不同浓度APN(0.5、1.0、1.5、2.5μg/mL)孵育脂肪性HepG2细胞及HL-7701细胞,将未经APN孵育的细胞作为对照。运用逆转录聚合酶链反应(RT-PCR)检测2种细胞AOX1基因表达,运用免疫印迹法检测2种细胞AOX1蛋白表达。结果与未经100μmol/L SFA孵育的对照组比较,经100μmol/L SFA孵育过的HepG2细胞及HL-7701细胞的AOX1基因及蛋白表达均明显增加(P<0.05),且HepG2细胞组明显高于HL-7701细胞组(P<0.05)。加入APN孵育细胞后,2种细胞AOX1基因及蛋白表达均明显低于未经APN孵育的对照组(P<0.05);并且随APN浓度升高,降幅增加。当APN浓度达到1.5μg/mL时,细胞AOX1表达的降低不再随APN浓度的增加而发生明显变化。在APN浓度相同的条件下,HepG2细胞组中AOX1基因及蛋白表达降低的幅度明显高于HL-7701细胞组。结论 APN能有效降低脂肪化肝脏细胞AOX1基因及蛋白表达,能很好的保护肝脏细胞,避免肝脏细胞发生NAFLD。

从菜油的动物试验评价其食用价值

关于高芥酸菜油食用问题,国内外很多人关心,见解不一,有的国家培养出低芥酸和无芥酸菜籽,有的国家仍旧按过去习惯食用。菜油是我国最主要的食油,有很久历史,目前我国人口平均食油量很少,比印度还少,我们怎样对待这个问题实属重要,影响很大,不得不慎重。兹将近几年菜油的动物试验国际文献选其有代表性的扼要摘录几条,内容是:(1)饲以菜油的动物体重问题;(2)与心脏影响问题,以供参考。

欧共体动物性食品中兽药的最高允许残留量

根据欧共体的有关规定,要逐步制定在欧共体范围内使用的兽药在动物性食品中的最高允许残留量(MRL),下表是某些兽药的情况。

Visceral fat and insulin resistance as predictors of non-alcoholic steatohepatitis

AIM： To examine whether visceral fat is associated with non-alcoholic steatohepatitis （NASH）, to assess for parameters associated with visceral adiposity and to investigate for factors associated with fibrotic severity in NASH. METHODS： Thirty NASH and 30 control subjects underwent biochemical tests, anthropometric assessment, bioelectrical impedance, dual energy X-ray absorptiometry and abdominal fat study by CT scan. Liver biopsies were graded according to the Brunt criteria. RESULTS： NASH subjects had elevated blood pressure, body mass index, waist circumference and waist-to-hip ratio. A greater number of diabetes rnellitus, impaired glucose tolerance test and HOMA-IR 〉 3.5 were found in NASH patients. HOMA-IR 〉 2.8 （OR 20.98, 95% CI 3.22-136.62; P 〈 0.001） and visceral fat area 〉 158 cm^2 （OR 18.55, 95% CI 1.60-214.67; P = 0.019） were independent predictors for NASH. Advanced stage of NASH was found in 15 （50%） patients. HOMA-IR 〉 3.5 （OR 23.12, 95% CI 2.00-266.23; P = 0.012） and grading of portal inflammation （OR 7.15, 95% CI 1.63-31.20; P = 0.009） were determined as independent risk factors for advanced stage of NASH. CONCLUSION： Obesity （especially central obesity） and metabolic syndrome are common in Thai NASH. Insulin resistance and elevated visceral fat are risk factors for the presence of NASH. The advanced stage of thedisease is related to insulin resistance.

Clinical implications of fatty pancreas:Correlations between fatty pancreas and metabolic syndrome

AIM:To investigate the clinical implications of lipid deposition in the pancreas(fatty pancreas). METHODS:The subjects of this study were 293 patients who had undergone abdominal computed tomography(CT)and sonography.Fatty pancreas was diagnosed by sonographic findings and subdivided into mild,moderate,and severe fatty pancreas groups comparing to the retroperitoneal fat echogenicity. RESULTS:Fatty pancreas was associated with higher levels for visceral fat,waist circumference,aspartate aminotransferase(AST),alanine aminotransferase (ALT),total cholesterol,triglyceride,high density lipoprotein,free fatty acid,γ-GTP,insulin,and the homeostasis model assessment of insulin resistance (HOMA-IR)than the control group(P<0.05).HOMAIR,visceral fat,triglyceride,and ALT also tended to increase with the degree of fat deposition in the pancreas on sonography.In a multivariate logistic regression analysis,HOMA-IR,visceral fat,and ALT level were independently related to fatty pancreas after adjustment for age,body mass index,and lipid profile.The incidence of metabolic syndrome in the fatty pancreas group was significantly higher than in the control group,and the numbers of metabolic syndrome parameters were significantly higher in the fatty pancreas group(P<0.05).CONCLUSION:Sonographic fatty pancrease showed higher insulin resistance,visceral fat area,triglyceride, and ALT levels than normal pancreases.Fatty pancreas also showed a strong correlation with metabolic syndrome.

Fatty liver disease in severe obese patients:Diagnostic value of abdominal ultrasound

AIM:To evaluate the sensitivity and specificity of abdominal ultrasound (US) for the diagnosis of hepatic steatosis in severe obese subjects and its relation to histological grade of steatosis. METHODS: A consecutive series of obese patients, who underwent bariatric surgery from October 2004 to May 2005, was selected. Ultrasonography was performed in all patients as part of routine preoperative time and an intraoperative wedge biopsy was obtained at the beginning of the bariatric surgery. The US and histological findings of steatosis were compared, considering histology as the gold standard. RESULTS: The study included 105 patients. The mean age was 37.2 ± 10.6 years and 75.2% were female. The histological prevalence of steatosis was 89.5%. The sensitivity and specificity of US in the diagnosis of hepatic steatosis were, respectively, 64.9% (95% CI: 54.9-74.3) and 90.9% (95% CI: 57.1-99.5). The positive predictive value and negative predictive value were, respectively, 98.4% (95% CI: 90.2-99.9) and 23.3% (95% CI: 12.3-39.0). The presence of steatosis onUS was associated to advanced grades of steatosis on histology (P = 0.016). CONCLUSION: Preoperative abdominal US in our series has not shown to be an accurate method for the diagnosis of hepatic steatosis in severe obese patients. Until another non-invasive method demonstrates better sensitivity and specificity values, histological evaluation may be recommended to these patients undergoing bariatric surgery.

Genetic and epigenetic variants influencing the development of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease （NAFLD） is common worldwide. The importance of genetic and epigen- eric changes in etiology and pathogenesis of NAFLD has been increasingly recognized. However, the ex- act mechanism is largely unknown. A large number of single nucleotide polymorphisms （SNPs） related to NAFLD has been documented by candidate gene studies （CGSs）. Among these genes, peroxisome pro- liferatoractivated receptor-γ, adiponectin, leptin and tumor necrosis factor-α were frequently reported. Since the introduction of genome-wide association studies （GWASs）, there have been significant advances in our understanding of genomic variations of NAFLD. Patatin- like phospholipase domain containing family member A3 （PNPLA3, SNP rs738409, encoding I148M）, also termed adiponutrin, has caught most attention. The evidence that PNPLA3 is associated with increased hepatic fat levels and hepatic inflammation has been validated by a series of studies. Epigenetic modification refers to phenotypic changes caused by an adaptive mechanism unrelated to alteration of primary DNA se- quences. Epigenetic regulation mainly includes microR- NAs （miRs）, DNA methylation, histone modifications and ubiquitination, among which miRs are studied most extensively, miRs are small natural single stranded RNA molecules regulating mRNA degradation or translation inhibition, subsequently altering protein expression of target genes. The miR-122, a highly abundant miR ac- counting for nearly 70% of all miRs in the liver, is sig- nificantly under-expressed in NAFLD subjects. Inhibition of miR-122 with an antisense oligonucleotide results in decreased mRNA expression of lipogenJc genes and improvement of liver steatosis. The investigation into epigenetic involvement in NAFLD pathogenesis is just at the beginning and needs to be refined. This review summarizes the roles of genetics and epigenetics in the development of NAFLD. The progress made in this field may provide novel diagnostic biomarkers and therapeu- tic targets for NAFLD management.

Effect of different intensities of physical activity on cardiometabolic markers and vascular and cardiac function in adult rats fed with a high-fat high-carbohydrate diet

Background: Physical activity(PA) and diet are 2 lifestyle factors that affect cardiometabolic risk. However, data on how a high-fat highcarbohydrate(HFHC) diet influences the effect of different intensities of PA on cardiometabolic health and cardiovascular function in a controlled setting are yet to be fully established. This study investigated the effect of sedentary behavior, light-intensity training(LIT), and high-intensity interval training(HIIT) on cardiometabolic markers and vascular and cardiac function in HFHC-fed adult rats.Methods: Twelve-week-old Wistar rats were randomly allocated to 4 groups(12 rats/group): control(CTL), sedentary(SED), LIT, and HIIT.Biometric indices, glucose and lipid control, inflammatory and oxidative stress markers, vascular reactivity, and cardiac electrophysiology of the experimental groups were examined after 12 weeks of HFHC-diet feeding and PA interventions.Results: The SED group had slower cardiac conduction(p = 0.0426) and greater thoracic aortic contractile responses(p < 0.05) compared with the CTL group. The LIT group showed improved cardiac conduction compared with the SED group(p = 0.0003), and the HIIT group showed decreased mesenteric artery contractile responses compared with all other groups and improved endothelium-dependent mesenteric artery relaxation compared with the LIT group(both p < 0.05). The LIT and HIIT groups had lower visceral(p = 0.0057 for LIT, p = 0.0120 for HIIT)and epididymal fat(p < 0.0001 for LIT, p = 0.0002 for HIIT) compared with the CTL group.Conclusion: LIT induced positive adaptations on fat accumulation and cardiac conduction, and HIIT induced a positive effect on fat accumulation,mesenteric artery contraction, and endothelium-dependent relaxation. No other differences were observed between groups. These findings suggest that few positive health effects can be achieved through LIT and HIIT when consuming a chronic and sustained HFHC diet.

Correlation between serum free fatty acids levels and Gensini score in elderly patients with coronary heart disease

Objectives To investigate the relationship between serum fxee fatty acids （FFAs） levels and the severity of coronary artery lesions in elderly patients with coronary heart disease （CAD）. Methods A total of 172 elderly patients who underwent coronary angiography were divided into CAD group （n = 128） and non-CAD group （n = 44） according to the results of coronary angiography. Serum FFAs and lipid levels were measured and the Gensini score were calculated. Results No matter the differences between age, gender and the usage of stat- ins or not, there was no statistical significance in FFAs levels （P 〉 0.05）. In terms of the Gensini score, it was higher in patients aged 70-79 years than in patients 60-69 years old [15.00 （5.00, 34.00） vs. 10.00 （2.00, 24.00）, P 〈 0.05], higher in men than women [14.00 （4.00, 34.00） vs. 7.00 （2.50, 19.75）, P 〈 0.05], and higher in patients on statins [13.50 （4.25, 33.50）vs. 6.50 （2.00, 18.00）, P 〈 0.05]. The serum FFAs lev- els [449.50 （299.00, 624.75） mEq/L vs. 388.00 （258.50, 495.25） mEq/L, P 〈 0.05J and Gensini score [17.50 （8.00, 41.75） vs. 1.00 （0, 5.00）, P 〈 0.05] were higher in the CAD group than in the non-CAD group. In the CAD group, there was no statistical significance in FFAs levels among patients with different numbers of diseased coronary vessels （P 〉 0.05）. Furthermore, the FFAs levels were positively correlated with the Gensini score （r = 0.394, P = 0.005）. Regression analysis showed that the FFAs levels were related to the Gensini score independently after adjusting for the other risk factors. Conclusions The serum FFAs levels were associated with the Gensini score in elderly patients with CAD. It might indicate FFAs as a biomarker predicting the severity of coronary artery lesions.

Nutritional recommendations for patients with non-alcoholic fatty liver diseases

Fatty liver is the most common liver disease worldwide.Patients with fatty liver disease die primarily from cardiovascular disease and not from chronic liver diseases.Hyperglycemia and hyperinsulinemia induce lipogenesis,thereby increasing the hepatic pool of fatty acids.This pool is also increased by increased delivery of fatty acids through the diet or lipolysis in adipose tissue.Nutritional consultations and lifestyle modification are important in the treatment of non-alcoholic fatty liver disease(NAFLD).Among the dietary constituents,combination of vitamin D,vitamin E,and omega-3 fatty acids shows promise for the treatment of NAFLD.

Sonographic fatty liver, overweight and ischemic heart disease

AIM: To demonstrate the prevalence of sonographic fatty liver, overweight and ischemic heart disease (IHD) among the male workers in Taiwan, and to investigate the possible association of these three factors.METHODS: From July to September 2003, a total of 2 088 male aircraft-maintenance workers aged from 22to 65 years (mean 40.5) underwent an annual health examination, including anthropometrical evaluation, blood pressure measurement, personal medical history assessment,biochemical blood analysis, abdominal ultrasonographic examination and digital electrocardiography (ECG). The Student's t-test, x2 test and multivariate logistic regression analysis were utilized to evaluate the relationship between IHD and salient risk factors.RESULTS: The all-over prevalence of overweight was 41.4%, and that of fatty liver was 29.5% (mild, moderate and severe fatty liver being 14.5%, 11.3%, and 3.7%,respectively); while the prevalence of ischemic changes on ECG was 17.1% in this study. The abnormal rates for conventional IHD risk factors including hypertension,dyslipidemia, hyperglycemia and overweight increased in accordance with the severity of fatty liver. Overweight and severity of fatty liver were independently associated with increased risks for developing IHD. Overweight subjects had a 1.32-fold (95%CI: 1.01-1.73) increased IHD risk. Participants with mild, moderate, and severe fatty liver had a 1.88-fold (95%CI: 1.37-2.6), 2.37-fold (95%CI: 1.66-3.37) and 2.76-fold (95%CI: 1.62-4.72)increased risk for developing IHD. The prevalence of ischemic ECG for the fatty liver-affected subjects with or without overweight was 30.1% and 19.1%, while that of overweight subjects free from fatty liver was 14.4%.Compared to the subjects without fatty liver nor overweight,IHD risk for the three subgroups above was as follows:OR: 2.95 (95%CI:2.31-4.09), OR: 1.60 (95%CI: 1.07-2.39)and OR: 1.11 (95%CI: 0.78-1.56), respectively.CONCLUSION: The presence of fatty liver and its severity should be carefully considered as independent risk factors for IHD. Results of the study suggest the synergistic effect between fatty liver and overweight for developing IHD.Abdominal sonographic examination may provide valuable information for IHD risk assessment in addition to limited report about liver status, especially for overweight males.

EXPERIMENTAL STUDY ON PRESERVATION OF RAT FATTY LIVER

OBJECTIVE: To investigate the effects of cold preservation on rat fatty liver. METHODS: We observed the changes of portal perfusion pressure, endothelin-1, enzymes release in the effluent and mortality of sinusoid lining cell after 0h, 6h, or 12h preservation respectively and a subsequent 30 min reperfusion in rat fatty liver groups and control groups by using isolated perfused rat liver model. And we compared fatty liver groups with control groups by these indices. RESULTS: There was no obvious difference between mildly fatty liver group and control group after long time (12h) preservation, between moderately fatty liver group and control group after short time (6h) preservation, between severely fatty liver group and control group without preservation (0h), while preservation reperfusion injury was more severe in moderately fatty liver group than in control group after long time (12h) preservation and in severely fatty liver group than in control group after short time (6h) preservation. CONCLUSIONS: The authors suggested that a mildly fatty liver donor could be used in the same way as nonfatty liver and a moderately fatty liver donor could be used depending on the time of preservation and the balance of the emergent needs of recipient and donor organ supply, while severely fatty liver donor should be discarded without hesitation.

Effect of Dietary Lipid on the Growth, Fatty Acid Composition and Δ5 Fads Expression of Abalone(Haliotis discus hannai Ino) Hepatopancreas

This study investigated the effect of dietary lipid on the growth, fatty acid composition and Δ5 fatty acyl desaturase genes(Fads) expression of juvenile abalone(Haliotis discus hannai Ino) hepatopancreas. Six purified diets were formulated to contain tripalmitin(TP), olive oil(OO, 72.87% 18:1n-9), grape seed oil(GO, 68.67% 18:2n-6), linseed oil(LO, 70.48% 18:3n-3), ARA oil(AO, 41.81% ARA) or EPA oil(EO, 44.09% EPA and 23.67% DAH). No significant difference in survival rate was observed among abalone fed with different diets. Weight gain rate(WGR) and daily growth rate of shell length(DGRSL) were significantly increased in abalone fed with diets containing OO, AO and EO, but decreased in abalone fed with LO diet(P < 0.05) in comparison with those fed with TP. High level of dietary 18:2n-6 resulted in higher content of n-6 polyunsaturated fatty acids(PUFAs) in abalone fed with GO than those fed with TP, OO, LO and EO(P < 0.05). n-3 PUFAs in abalone fed with LO was significantly higher than those in abalone fed with TP, OO, GO and AO(P < 0.05). The highest contents of 20:1n-9 and 22:1n-9 were observed in abalone fed with OO. The expression of Δ5 Fads in hepatopancreas of abalone was enhanced by high concentration of 18:3n-3 and suppressed by dietary LC-PUFAs; however it was not affected by dietary high concentration of 18:1n-9 or 18:2n-6. These results provided valuable information for understanding the synthesis of LC-PUFAs and nutritional regulation of Δ5 Fads expression in abalone.

Diagnostic Value of Hepatic Enzymes, Triglycerides and Serum Proteins for the Detection of Hepatic Lipidosis in Chelonoidis carbonaria in Captivity

Hepatic lipidosis is a common lesion in chelonians and may be related with vitellogenesis, hyperparathyroidism, follicular stasis, fatty diets or lacking nutrients, sedentary life and obesity, bacterial toxins in liver and starvation. Clinical signs are unspecific. Routine biochemical tests don＇t have specificity and it is better defined through biopsy. The objective was evaluated the biochemical hepatic profile of red footed tortoises （Chelonoidis carbonaria） with the histopathological findings of lipidosis by laparoscopic biopsy. Samples of blood were collected for biochemistry of thirty-six animals from two different groups, twenty animals from a zoo and sixteen from a breeder. The animals were submitted to liver biopsy by videolaparoscopy. Three fragments were collected, two of them were processed by histology and one went to electron microscopy. Nineteen tortoises from the zoo had lipidosis in laparoscopy and macrovesicular degeneration. Fifteen tortoises from the breeder had microvesicular degeneration. The diagnosis of steatosis was confirmed by electron microscopy. There was no statistical difference of aspartate aminotransferase levels between the two groups; however there was significant difference of triglycerides levels. The enzymatic activity of transaminases is not related to the histological grading of lipidosis in tortoises, however triglycerides levels are higher in animals with more severe gradation.

Effect of BEDGEN 40 on Growth, Anti-Oxidant Activity and Resistance against Aeromonas Hydrophila Infection in Tilapia （Oreochromis niloticus x O. aureus）

The globe artichoke has become important as a medicinal herb in recent years following the discovery of cynarin. This bitter-tasting compound, which is found in the leaves, improves liver and gall bladder function, stimulates the secretion of digestive juices, especially bile, and lowers blood cholesterol levels. The leaves are anticholesterolemic, antirheumatic, cholagogue, digestive, diuretic, hypoglycaemic and lithontripic. BEDGEN 40 , a compound made with Cynara scolymus L. （artichoke） extract and choline chloride was evaluated for growth performance and anti-oxidant activity in tilapia. There were four treatment groups; group 1 was fed only with a basal diet and served as the control, group 2 - 4 were experimental groups that received 150, 300, or 600 mg/kg BEDGEN 40 , respectively, added to the basal diet and fed for 8 weeks. The results showed signifi- cant differences for weight gain, feed conversion, and protein efficiency in fish diets containing 150, 300, or 600 mg/kg BEDGEN 40 compared to the control. Generally, BEDGEN 40 improved the body condition factor and hepatosomatic index of tilapia, and reduced liver fat content. Fish consum- ing BEDGEN 40 also exhibited improved liver antioxidant status. BEDGEN 40 （300, or 600 mg/kg） was also found to significantly reduce the mortality of tilapia subsequently challenged with Aeromonas hydrophila.

Hepatic steatosis prevents heme oxygenase-1 induction by isoflurane in the rat liver

AIM:To characterize the inductive effects of isoflurane(ISO) on hepatic heme oxygenase-1(HO-1) in an animal model of hepatic steatosis.METHODS:Lean(LEAN) and obese(FAT) Zucker rats were randomized into 4 groups:1:LEAN + pentobarbital sodium(PEN);2:LEAN + ISO;3:FAT + PEN;4:FAT + ISO.The animals were mechanically ventilated for 6 h.In vitro analyses of liver tissue included determination of HO-1 mRNA and protein expression as well as measurement of HO enzyme activity and immunohistochemical analyses.RESULTS:Compared to PEN treatment,ISO administration profoundly induced hepatic HO-1 mRNA and protein expression and significantly increased HO enzyme activity in lean Zucker rats.In contrast,no difference in HO-1 gene expression was observed after ISO or PEN anesthesia in obese Zucker rats.CONCLUSION:The present study demonstrates that ISO is an inducer of hepatic HO-1 gene expression in non-steatotic organs but failed to upregulate HO-1 in steatotic livers.

胰腺脂肪浸润的研究进展

胰腺的甘油三酯沉积过多，或胰腺组织发生脂肪替代时，会形成“胰腺脂肪浸润”。根据其脂质沉积于细胞内外的不同，发生机制也不相同。虽然组织学检查为诊断胰腺脂肪浸润的金标准，但临床上常应用影像学技术进行确诊，且核磁共振技术与生化测量具有高度一致性。由于胰腺脂肪浸润可影响胰腺本身及其他疾病的发生、发展，因此对其早期诊断和干预可为治疗相关疾病提供新思路。

高能低蛋白日粮致脂肪肝出血综合征鸡抗氧化能力和肝损伤的研究

选用140日龄健康海兰褐壳蛋鸡102只,随机分为对照组(饲喂日粮代谢能与粗蛋白分别为11.51MJ/kg、15.58%)和试验组(饲喂日粮代谢能与粗蛋白分别为14.47MJ/kg、12.55%),每组设3个重复,每个重复17只。于试验期第15、25、35、45、55天,每组取6只鸡测定其血清和肝脏中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性和丙二醛(MDA)含量,同时对肝脏作病理组织学检查。结果显示:(1)试验组蛋鸡表现肝脂蓄积,肝脂肪变性,出现典型脂肪肝出血综合征病变,证明高能低蛋白日粮可以成功复制蛋鸡脂肪脏出血综合征。(2)与对照组相比,试验组血清和肝脏匀浆中MDA含量升高,抗氧化酶SOD、GSH-Px、CAT活力最终都降低,表明机体抗氧化能力下降。结果表明,自由基在高能低蛋白日粮致脂肪肝出血综合征的发生、发展过程中起重要作用。

The role of visceral adipose tissue on improvement in insulin sensitivity following Roux-en-Y gastric bypass:a study in Chinese diabetic patients with mild and central obesity

Background:Most Chinese patients with type 2 diabetes mellitus(T2DM)have mild obesity and central obesity.Central obesity is combined with insulin resistance.The aim of this study was to assess the effect of abdominal adipose tissue on insulin-sensitivity improvement after Roux-en-Y gastric bypass(RYGB)in Chinese diabetic patients with mild and central obesity.Methods:Seventeen T2DM patients with a mean body mass index of 30.3 kg/m^(2) were scheduled for laparoscopic RYGB.A hyperinsulinemic-euglycemic clamp and dual-energy X-ray absorptiometry were performed prior to surgery and 3 months after RYGB.The primary end points were the correlations between insulin sensitivity and abdominal adipose tissue,including visceral adipose tissue(VAT)and subcutaneous adipose tissue(SAT),before and 3 months after RYGB.Results:Indices of peripheral insulin sensitivity,including glucose-disposal rate(M value)and glucose infusion rate,were significantly increased after RYGB.Body-fat mass,VAT and SAT were significantly reduced after RYGB.The pre-operative M value was significantly correlated with VAT mass(r=–0.57,P=0.02),but not correlated with SAT mass.M value changes after RYGB were highly correlated with changes in VAT mass(r=–0.59,P=0.01),percentage of VAT mass(r=–0.66,P<0.01),VAT area(r=–0.56,P=0.02)and percentage of VAT area(r=–0.57,P=0.02).Conclusions:A significant correlation was observed between increased peripheral insulin sensitivity and decreased VAT following RYGB in Chinese patients with mild and central obesity.VAT and SAT were significantly decreased with improved insulin sensitivity after RYGB.VAT mass may be considered as an indication for gastric bypass during patient selection.