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Objective To understand the relation between smoking and serum uric acid level and to investigate whether the ser-um uric acid has the correlation with the gender,age and smoking history.Methods The data of the gender,age,blood uric acid in1 847 individuals aged 20-80 years with the healthy physical examination and without underlying diseases were performed the statisti-cal analysis.Results With male and female as the research objects,the serum uric acid level of smokers were higher than that of non-smokers and occasional smokers,the difference was statistically significant;the serum uric acid level had no statistically signifi-cant difference between smokers and occasional smokers;the serum uric acid level had no statistically significant difference among non-smoking,occasional smoking and smoking groups for males as the research objects alone;to divide the male subjects into groups according to age,the serum uric acid level of non-smokers,occasional smokers and smokers were not statistically significant among all age groups;serum uric acid level showed the increasing trend with the increase of smoking history,but there was no statistically significant difference.Conclusion The serum uric acid level of smokers is significantly higher than that of non-smokers and occa-sional smokers with male and female as the research objects;the difference in serum uric acid level between smokers and occasional smokers has no statistical significance;excluding the gender factor interference,the serum uric acid level of males is not affected by smoking or age;serum uric acid mean value demonstrates the increasing trend with the increase of smoking history.
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Objective:To explore the hepatocyte insulin sensitivity of intrauterine growth retardation ( IUGR) rats and establish an insulin resistance cell model in vitro.Methods: An IUGR animal model was established by protein malnutrition during the mother pregnancy .On 60 d and 90 d after birth , the offspring rats were fasted for 12 hours and then their angular vein blood was collected to measure the fasting plasma glucose and fasting serum insulin level , then the insulin resistance index ( HOMA-IR) and insulin sensitivity index ( ISI) were calculated .The insulin sensitivity was evaluated by HOMA-IR and ISI.Primary hepatocytes from each group were respectively isolated by two-step perfusion with collage-nase and were defined as normal hepatocytes group and IUGR hepatocytes group .The normal hepatocyte group was divided into two groups: control group and insulin induction group .Insulin induction group was established by primary cultures of normal hepatocyte incubated with varying dilutions of insulin . CCK-8 was used to detect the viability of the cultured hepatocytes .Glucose oxidase-peroxidase method kit was used to measure glucose consumption of the hepatocytes .Results:HOMA-IR was significantly higher in IUGR rats than in the normal rats at the age of 60 days ( t=-17 .02 , P<0 .05 ) and 90 days ( t=-12.52, P<0.05).ISI was significantly lower than in the normal rats aged 60 days (t=5.61, P<0.05) and 90 days (t=12.42, P<0.05).There were no significant differences in hepatocyte viability among the control group , IUGR group and insulin induction group after incubation of 48 h on day 60 (F=1.34, P=0.29) and day 90 (F=0.22, P=0.81).The glucose consumption of the IUGR group and insulin induction group were significantly decreased compared with the control group on day 60 ( F=9.28, P=0.002) and day 90 (F=56.60, P<0.001), while there was no significant difference be-tween the IUGR group and insulin induction group (P=0.08, P=0.10).Conclusion:The insulin sen-sitivity of hepatocytes of IUGR rats decreased from adolescence to adulthood .High-dilution insulin may induce insulin resistance cell model in vitro.
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Objective To investigate polymorphism in the promoter region of insulin-like growth factor-1(IGF-1) gene.Methods Five hundred and sixty-one neonates admitted to Peking University Third Hospital from June 1st,2010 to June 30th,2012 were recruited into the study.Gender,gestational age,birth weight and birth length were collected.Heel blood samples were collected on 3-5 days after birth.DNA was extracted to analyze the polymorphism in the promoter region of IGF-1 gene.Chi-square test,independent-sample t-test,analysis of variance and HardyWeinberg equilibrium were performed.Results Among the 561 neonates,413 were full term,and 148 were preterm; 92 were large for gestational age (LGA),433 were appropriate for gestional age (AGA),and 36 were small for gestional age (SGA).Seven different alleles and 23 genotypes in the promoter region of IGF-1 gene were identified in the population.The seven alleles were 188,190,192,194,196,198 and 200 bp respectively.The three most common genotypes were 190-192 bp,192-196 bp and 192-192 bp,whose frequencies were 23.2％ (130/561),15.0％ (84/561) and 12.8％(72/561).There were no significant differences of cytosine-adenosine (CA)19/CA19,CA19/CAno19and CAno19/CAno19 genotypes between full term and preterm infants [11.4％ (47/413) vs 16.9％(25/148),55.9％ (231/413) vs 50.7％ (75/148) and 32.7％ (135/413) vs 32.4％ (48/148)respectively,x2=2.96,1.21 and 0.00,all P＞0.05].There was no difference in the gestional age among infants with CA19/CA19,CA19/CAno19 and CAno19/CAno19 genotypes [(37.1±2.9),(37.6±3.1) and (37.4±3.1) weeks respectively,F=0.54,P=0.58].The frequency of CA19/CA19 in SGA neonates was higher than that in LGA and AGA neonates [25.0％ (9/36) vs 7.6％(7/92) and 12.9％ (56/433),x2 =7.01,P=0.03],but there were no differences in the frequency of CA19/CAno19 and CAno19/CAno19 among LGA,AGA and SGA neonates (CA19/CAno19:x2 =1.13,P=0.57; CAno19/CAno19:x2 =0.58,P=0.75).Conclusions Polymorphism exists in the promoter region of IGF-1 gene.The gestational age is not associated with the frequency of CA19 allele.
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Objective To investigate the effect of liver phosphatidylinosital 3-kinase/protein kinase B (PI3-K/AKT) pathway on the decrease of insulin sensitivity in fetal growth restriction (FGR) rats.Methods Twenty pregnant female rats were randomly divided into two groups one day after conception:normal-protein group and low protein group (n=10,respectively).Rats in low-protein group was given low protein diet (8.00％ protein) during pregnancy to build FGR model,while normal-protein group was given normal protein diet (20.00％ protein).On day 3,7,14,30,60 and 90 after birth,fasting blood samples of 8 male FGR offsprings from low-protein group and 8 normal offsprings from normal-protein group were collected to measure fasting plasma glucose and insulin level.Then insulin resistance index and insulin sensitivity index were calculated to determine insulin sensitivity.On day 7,14,30,60 and 90 after birth,liver tissue of 8 male FGR and normal offsprings were collected,insulin receptor substrate 1,2 (IRS1/IRS2)and glucose transporter 4 (GLUT4) mRNA expression were measured by real-time fluorescence polymerase chain reaction and the protein expressions of IRS1,PI3-K (subunit p110β),and AKT and phosphorylated AKT (pAKT) were measured by Western blot.The relationships between the expression changes of key molecules of PI3-K/AKT pathway and insulin sensitivity were analyzed by correlation and multiple linear regression method.Results (1) Mean birth weight of baby rats in low-protein group was significantly lower than that of normal-protein group [(4.92±0.36) g vs (6.43±0.59) g,t=14.73,P＜0.05].The incidence of FGR in low-protein group was 88.2％ (97/110); and for male offsprings,it was 94.1 ％ (48/51).(2) Compared to normal offsprings,fasting plasma glucose levels of male FGR offsprings were significantly higher from the age of 60 days to 90 days.Insulin levels and insulin resistance index were significantly higher and insulin sensitivity index was lower from the age of 30 days to 90 days,P＜0.05 respectively.(3) Compared to normal offsprings,IRS1 (0.45 ± 0.02 vs 0.68± 0.03,t=16.633,P＜0.05) and IRS2 mRNA (0.34±0.10 vs 0.70±0.19,t=4.864,P＜0.05) expressions in FGR offsprings were lower from day 7 after birth to day 90 (0.48±0.03 vs 0.59±0.05,t=5.237,P＜0.05; 0.49±0.20 vs 0.70±0.11,t=2.253,P＜0.05).There were no differences in expressions of GIUT4 mRNA and AKT protein between two groups (P＞ 0.05).IRS1,PI3-K and pAKT protein expressions of FGR offsprings decreased significantly from day 14 (0.22±0.05 vs 0.52±0.11,t=7.024,P＜0.05; 0.46±0.03 vs 0.97±0.08,t=17.508,P＜0.05; 0.62±0.10 vs 0.89±0.08,t=6.100,P＜0.05) to day 90 (1.11±0.08 vs 1.32±0.14,t=3.714,P＜0.05; 0.63±0.07 vs 1.00±0.19,t=5.206,P＜0.05;0.28±0.03 vs 0.45±0.10,t=4.880,P＜0.05).(4) The pAKT protein expression level of FGR rats was positively correlated with insulin sensitivity index (r=0.704,P＜0.05) ; while negatively correlated to the level of fasting plasma glucose (r=-0.609,P＜0.05),fasting insulin (r=-0.561,P＜0.05) and insulin resistance index (r =0.577,P＜ 0.05).Conclusions The changes of some key molecules' expressions of PI3-K/AKT pathway in liver might be involved in the insulin resistance in FGR rats.
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Objective To explore the effect of methylation of peroxisome proliferator-activated receptor γ(PPARy) gene promoter in liver and its mRNA expression changes on decreasing of insulin sensitivity in fetal growth restriction (FGR) rats.Methods Twenty pregnant rats were randomly divided into two groups on their first day of pregnancy:normal-protein group (NP) and low-protein group (LP),ten in each.During pregnancy the LP group rats were fed with low-protein diet (8.00％ protein),while the NP group rats were fed with normal-protein diet (20.00％ protein).The offspring rats were fed with standard feed after 21 days of birth.Male offsprings in NP group were as control offsprings,and male FGR offsprings in LP group ware as FGR offsprings.At day 3,7,14,30,60 and 90,fasting blood of offsprings was collected to measure fasting plasma glucose (FPG) and fasting insulin(FINS).Then insulin resistance index of homeostasis model assessment (HOMA-IR) and insulin sensitivity index (ISI) were calculated to evaluate insulin sensitivity.At day 7 and 90,liver tissue of male offsprings was collected to extract DNA and total RNA.The methylation level of PPARγ gene promoter and its mRNA expression were detected by methylation specific-polymerase chain reaction (MS-PCR) and reverse transcription-RCR,respectively.The relationships between methylation of PPARγ gene promoter and mRNA expression and insulin sensitivity were analyzed by Pearson correlation and nonparametric test method.Results (1) The mean offspring birth-weight of LP group was (4.92±0.36) g,which was lower than that [(6.43±0.59) g] of control group (t=14.73,P＜0.05).In LP group,the incidence of FGR offspring was 88.2％ (97/110) and the FGR incidence of male ones was 94.1％ (48/51).(2) At day 90,compared with control offsprings,FPG [(8.95±1.83) mmol/L vs (6.21±1.14) mmol/L,t=-3.291,P＜0.05],FINS [(59.57±9.89) mU/Lvs (36.10±7.32) mU/L,t=-4.916,P＜0.05] and HOMA-IR (0.967±0.297 vs 0.410±0.135,t=-4.472,P＜0.05) of FGR offsprings were significantly higher; while ISI of FGR offspring was lower than that of control offsprings (-3.043±0.294 vs -2.172±0.354,t=4.774,P＜0.05).(3) There was no significant difference in methylation degree of PPARγ gene promoter in liver between FGR and control offsprings at day 7 (0/8 vs 2/8,Fisher exact test,P＞0.05).The methylation degree of PPARγ gene promoter in liver in FGR offsprings was significantly higher than that of control offsprings at day 90 (8/8 vs 2/8,Fisher exact test,P＜0.05).Compared with control offsprings,PPARγ gene mRNA expression level of FGR offsprings decreased significantly at day 90 (4.3.07±7.51 vs 146.72± 40.66,t=7.09,P＜0.05).mRNA expression of PPARγ gene was the lowest in exhaustive methylation offsprings (27.2± 1.6),and then in partial methylation ones (47.3±33.0),the highest in no methylation ones (144.6 ± 21.2) (P＜0.05).(4) The correlation analysis showed that PPARγ mRNA expression level negatively correlated to the level of FPG (r=-0.819),FINS (r=-0.906) and HOMA-IR (r=-0.860),P＜0.05 respectively; but positively correlated to ISI level (r=0.947,P＜0.05).Conclusions Hypermethylation in promoter region of PPARγ gene might inhibit gene transcription,and be involved in the occurrence of insulin resistance in FGR rats.
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Objective To investigate the regular pattern of dynamic changes of insulin sensitivity in fetal growth restriction (FGR) rats. Methods Twenty pregnant female rats were randomly divided into two groups as normal-protein group (NP) and low-protein group (LP), which respectively received normal protein diet (20% protein) and low protein diet (8% protein) during pregnancy. Weights of newborns were measured within 6 hours after birth, and the LP offspring whose birth weights were at least 2 standard deviations below the mean of NP offspring (≤2 standard deviations) were defined as FGR rats. At day 3, 7, 14, 30, 60 and 90 after birth, rats were fasted for 12 hours and then angular vein blood was collected to measure fasting plasma glucose (FPG) and fasting serum insulin (FINS) level. At 90 days of age, intraperitoneal glucose tolerance test (IPGTT)was performed; and blood triglyceride ( TG ), low-density lipoprotein cholesterol ( LDL-C ),high-density lipoprotein cholesterol (HDL-C) and glycosylated hemoglobin Alc (HbAlc) were measured. Insulin sensitivity was evaluated by FINS, insulin resistance index (HOMA-IR), insulin sensitivity index (ISI) and IPGTT. Results (1) Birth weights of LP offspring [(4. 92 ± 0. 36) g]were significantly lower than those of NP ones [(6. 43 ± 0. 59) g] (t = 14. 73, P＜0. 05). The incidence of FGR in LP was 88. 2% ; and for the male and female rats, the FGR rate was 94. 1% and 83. 1%, respectively. (2) FPG levels in the male FGR rats were significantly higher than in the NP from the age of 60 days [(9.38 ± 1.57) mmol/L vs (5. 58 ± 1.24) mmol/L] to 90 days [(8. 95 ±1.83) mmol/L vs (6. 21± 1.14) mmol/L] (t=-3. 291, P＜0. 05), while FPG levels in female FGR rats increased significantly only at 90 days of age [(9. 08±1.65) mmol/L vs (6.73±0. 67) mmol/L](t=-3. 226,P＜0. 05). FINS levels were significantly higher in FGR rats than in the NP from the age of 30 days (male FGR rats) or 60 days (female FGR rats) to 90 days (P＜0. 05, respectively).Similarly, HOMA-IR was significantly higher in FGR rats than in the NP at the age of 30 days (male FGR rats) or 60 days (female FGR rats) to 90 days (P＜0. 05, respectively). ISI in male FGR rats showed a reduction in comparison with the NP from the age of 30 to 90 days, while as to the female FGR rats it was significantly lower than in the NP only at 60 days of age and continued to 90 days (P＜0. 05, respectively). IPGTT showed that after injection of glucose, blood glucose at all four points (from 0 min to 120 min) in both male and female FGR rats were higher than that in the NP (P＜0. 05). (3) No significant difference was observed in TG, LDL-C and HDL-C at 90 days of age between the FGR rats and NP ones, while HbA1c in the male FGR rats was significantly higher than that in the NP [(7. 03±0. 54) % vs (4. 37±0. 64)%,t= -8. 028, P＜0. 05]. Conclusions FGR rats are able to maintain glucose balance and normal insulin levels during their earlier age, while insulin sensitivity decreased from adolescence to adulthood. The change of insulin sensitivity is different between male and female FGR rats, and male FGR rats are more likely to develop insulin resistance.
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Objective To investigate the effects of pregnancy complicated with diabetes on the insulin sensitivity of offspring during their early childhood. Methods Offspring of diabetic mothers(ODM) and of non-diabetic mothers(ONDM) aged 1 month to 24 months were recruited into this prospective cohort study and followed up for two years. Body weight and body length were measured at 2, 4, 6, 8, 10, 12, 18 and 24 months of age respectively, and body mass index (BMI) were calculated. Fasting plasma glucose and fasting serum insulin levels were measured on the following-up day at 6, 12 and 24 months of age and insulin sensitivity index (ISI) was calculated. Homeostasis model assessment was used to calculate the insulin resistance (HOMA-IR). Insulin sensitivity was evaluated by fasting serum insulin, ISI and HOMA-IR. The difference of insulin sensitivity between ODM and ONDM group were examined by analysis of covariance adjusted by gender, gestational age,birth weight and BMI. Results Six hundred and five babies including ninety ODM and five hundred and eleven ONDM met the inclusion criteria. There were no differences in gender, gestational age,birth-weight/height between the two groups(P＞0. 05). ODM were heavier and higher than ONDM at each measure point during early childhood, but there were statistical differences at the age of 2, 4 and 6 months only (P＜0. 05). And the BMI at age of 2 and 4 months of ODM were higher than those of ONDM(P＜0.05). The number of baby who accepted the measurement of fasting plasma glucose and fasting serum insulin levels at 6, 12 and 24 months of age was 276 cases, 273 cases and 56 cases respectively. The fasting serum insulin of ODM (logarithmically transformed) were 0. 95±0. 30,0. 89±0. 34 and 0. 90±0. 27, which were higher than those of ONDM (0. 70±0. 45, 0. 73±0. 35 and 0. 67±0. 30) (t=9. 58, 5.01 and 6. 11, P＜0.05); HOMA-IR (logarithmically transformed) were 0. 34±0. 33, 0. 27±0. 36 and 0. 27±0. 31, which were higher than those of ONDM also(0.08±0. 46,0. 10±0. 36 and 0. 03 ± 0.33) (t= 9. 55, 4. 79 and 5. 06, P＜0.05); ISI(natural logarithmically transformed) were -3.87±0. 75, -3.73±0. 81 and -3. 73±0. 71, which were lower than those of ONDM(-3.29±1.05, -3.35±0.84 and -3.18±0. 77) (t=9.20, 4. 90 and 5.06, P＜0.05).There were differences in feeding characteristics of ODM between insulin sensitive subgroup [40. 9%(9/22) breast-feeding] and insulin insensitive subgroup [16.67 % (12/72) breast-feeding] (x2 = 7.02,P=0. 03). Conclusions Pregnancy complicated with diabetes has adverse effects on the offspring insulin sensitivity during their early childhood, and affects the early growth and development of them.Breast-feeding might decrease insulin resistance in babies.