RESUMO
Aim To explore the role of angiotensin U type 1 a reeeptor ( AT 1 aR ) , an important component of HAS, in obesity-induced insulin resistance.Methods Wild type ( WT) and ATlaR gene knockout (ATlaR ) SD rats were fed with normal diet and 60% high-fat diet for 12 weeks, respectively.After 12 weeks, blood was collected from the abdominal aorta of rats to obtain serum, and the serum insulin level was measured by ELISA.The epididvmal adipose tissue was obtained, and gene expressions of peroxisome pro- liferator-activated receptor -y ( PPAR7) and sterol reg¬ulator}' element binding protein lc (SREBP-lc) in ad¬ipose tissue were detected by RT-PCR method.The protein expressions of insulin signaling pathway and protein kinase C (PKC) in adipose tissue were detec¬ted by Western blot.Results ATI aR knockout signif¬icantly reduced HOMA-IR and improved insulin resist¬ance induced by high-fat diet.In ATlaR rats fed with high-fat, the protein expressions of insulin signa¬ling pathway were much higher than those of WT rats, indicating that ATlaR gene knockout improved the in¬sulin signaling pathway in high-fat diet.In addition, the PKCa, PKCe and PKCr| expressions of ATlaR rats were significantly lower than those of WT rats.And the gene expressions of PPAR-y and SREBP-lc, which promoted adipogenic differentiation, significantly increased in ATlaR rats fed with a high-fat diet, demonstrating that ATlaR knockout promoted adipo¬genic differentiation.Conclusions ATlaR knockout significantly improves high-fat diet induced 1R by en¬hancing protein expressions of insulin signaling path¬way, inhibiting PKC expression and promoting adipo¬genic differentiation.
RESUMO
Fatigue refers to the manifestation of disorders in the process of carrying out or maintaining random activities， which can be regarded as an independent disease or as a symptom in a variety of chronic diseases. The high incidence of fatigue has seriously affected people's physical and mental health， and the prevention and treatment of fatigue has become an important problem to be solved urgently. The pathogenesis of fatigue mainly includes energy consumpation， accumulation of metabolites， abnormal secretion of neurotransmitters， decline of mitochondrial function， dysfunction of hypothalamus pituitary adrenal axis， etc. At present， there is no unified understanding about the pathogenesis of fatigue at home and abroad. The gene research of fatigue is the current research frontier. Gene expression profiling provides a new method for the study of the mechanism of fatigue. The combination of gene chip technology and traditional Chinese medicine（TCM） theory is expected to bring a breakthrough in the study of the pathogenesis of fatigue. In the study of fatigue gene chip， messenger RNA（mRNA） and microRNA（miRNA） are the common research objects， but few explorations are focused on the gene expression rule of fatigue by a specific signaling pathway and the effective regulation targets of TCM for treating fatigue. In recent years， the dysfunction of reward and inhibition mechanism in the central nervous system has become a research hotspot. In particular， gamma amino butyric acid （GABA） and dopamine （DA） have attracted much attention as the main substances of inhibition and reward mechanism， respectively. GABA and DA are used as inhibition and reward mechanisms to maintain the balance， and the body will not feel fatigue. Once the balance is broken， the fatigue will be formed. At the same time， DA and GABA receptors can also regulate cyclic adenosine monophosphate signaling pathway（cAMP） to affect fatigue. The research on key genes in GABA/DA balance mechanism and related cAMP signaling pathway by gene chip technology is expected to reveal the pathogenesis of fatigue in depth. The gene chip method is used to detect the changes of key genes in GABA/DA pathway and the related cAMP signaling pathway in the fatigue population and the normal population， so as to further explore the pathogenesis of fatigue. In this paper， the key genes in GABA/DA balance mechanism and cAMP signaling pathway related to fatigue were summarized by using the review method， so as to provide the basis for further study on the pathogenesis of fatigue and effective prevention and treatment from the perspective of genetics.
RESUMO
Objective To investigate the effects of fibroblast growth factor 2 (FGF-2) combined with tanshinoneⅡA on differentiation of rat bone marrow mesenchymal stem cells (BMSCs) into cardiomyocyte-like cells. Methods BMSCs were isolated and cultured. The cultured cells were identified by flow cytometry, BMSCs were divided into experimental control group, FGF-2 group, tanshinoneⅡA group and the combined induction group. The activity and value of BMSCs were detected by MTT. The Real-time PCR method was used to detect BMSCs. Expression of early myocardial transcription factors GATA-4 and Nkx2. 5; Immunocytochemical staining for detection of connexin43(Cx43)and cardiac troponin-Ⅰ(cTnI); Immunofluorescence staining for detection of desmin and Tm; The expression of desmin and tropomyosin(Tm)was detected by Western blotting. Results The cell activity and proliferation after induction were good. The expression of GATA-4 and Nkx2. 5 in the induction group were stronger than that in the experimental control group, and the difference was statistically significant (P<0. 05). The positive expression of Cx43 and cTnI in the induction group increased significantly. The markers of the combined group were the most obvious, and the difference was statistically significant (P<0. 05). The expression of Myo-specific protein desmin and Tm in the combined induction group increased significantly, and the difference was statistically significant (P<0. 05). Conclusion Both FGF-2 and tanshinoneⅡA can promote the proliferation of BMSCs and induce the differentiation of BMSCs into cardiomyocyte-like cells. The synergistic effect of the two is better than other groups.
RESUMO
Objective To observe the effect of different levels of iodine nutrition on rat maternal thyroid function during pregnancy.Methods A total of 225 Wistar rats one month after weaning were involved in the study(female 165,male 60,body mass 80 to 100 g).Female rats were randomly divided into six groups by body mass:control group(NI group),iodine deficiency 1 and 2 groups(LI1,LI2 groups),iodine excess 1 and 2 groups (HI1,HI2 groups),and the control of not pregnant group(NNI group).There were 30 rats in 1-5 groups and 15 rats in group 6.LI1,LI2 groups:low iodine diet + deionized water of no iodine or iodine-containing 5 μg/L; HI1,HI2 groups:normal diet + deionized water of iodine 3000,10 000 μg/L; NI,NNI groups:normal diet + deionized water of iodine-containing 50 μg/L.After 12 weeks,the females(except group 6) mated the male by 2 ∶ 1,and then each pregnant female rat was fed in a single cage.The female mice were sacrificed in the first(5 ± 2)d,the second (12 ± 2)d and the third trimesters of pregnancy (17 ± 2)d,respectively,and there blood samples and thyroid were obtained.Serum total thyroxine(TT4),free thyroxine(FT4),total triiodothyronine (TT3),free triiodothyronine (FT3) and thyroid stimulating hormone(TSH) were determined by radioimmunoassay and serum thyroglobulin(TG) and thyroid-binding globulin (TBG) were determined by enzyme-linked immunosorbent assay.Results ①Thyroid absolute quality and relative quality was compared among groups,and the differences were statistically significant (F =16.55,24.25,F ＜ 0.01 or ＜ 0.05).②At the first,the second and the third trimesters of pregnancy,the differences of maternal serum TT4 and FT4 between groups were statistically significant(F =5.02,13.41,17.39,41.89,23.72,48.64,P ＜ 0.01 or ＜ 0.05).Female rats in NI,HI1 and HI2 groups in different pregnant periods among inner groups were compared,and the differences of serum TT4 and FT4 were statistically significant(F=3.27,6.98,8.22,8.65,29.68,7.90,P ＜ 0.01 or ＜ 0.05).③ In the first and the third trimesters of pregnancy,maternal serum TT3 was compared among groups,and the differences were statistically significant(F=3.59,8.22,P ＜ 0.05 or ＜ 0.01) ; in the second and the third trimesters of pregnancy,maternal serum FT3 was compared among groups,and the difference was statistically significant(F =3.86,4.26,P ＜ 0.05 or ＜ 0.01).Female rats in NI,LI1 and HI1 groups in different pregnant periods among inner groups were compared,and the differences of maternal serum TT3 were statistically significant(F =8.77,7.11,6.28,P ＜ 0.01 or ＜ 0.05).④At the first,the second and the third trimesters of pregnancy,the differences of maternal serum TG and TBG were compared in groups,and the differences were statistically significant(F =5.47,3.62,9.35,4.15,13.16,22.78,P ＜ 0.01 or ＜ 0.05).The differences of maternal serum TG of HI1 group and of serum TBG of NI group in different pregnant periods among inner groups were statistically significant (F =3.18,7.94,P ＜ 0.05).⑤At the first,the second and the third trimesters of pregnancy,the differences of maternal serum TSH in groups were statistically significant(F =4.83,7.08,6.52,P ＜ 0.01); the differences of maternal serum TSH of all the 5 groups in different pregnant periods among inner groups were statistically significant (F =3.26,8.89,11.45,4.04,3.78,P ＜ 0.05).Conclusions Different levels of iodine nutrition can cause changes in thyroid function in rats maternal thyroid function during pregnancy; serum TT4,FT4 level decreases when iodine deficiency,and increase with iodine excess.Serum TT3,FT3 level of does not changed significantly due to compensatory regulation of the body.
RESUMO
Objective To study the effects of different iodine intakes on rat iodine metabolism during pregnancy.Methods One hundred and fifty female Wistar rats (body weight 80-100 g) were randomly divided into five groups:control group(NI),lower iodine 1 and 2 groups(LI1 and LI2),High iodine 1 and 2 groups(HI1 and HI2) by weight,30 rats in each group.These rats were given deionized water containing different concentrations of iodine,50(NI),0 (LI1),5(LI2),3000(HI1) and 10000 μg/L(HI2),respectively.After 12 weeks,urine samples were collected before copulation.The rats were sacrificed at the first(6-7 days),second (12-13 days) and third trimesters(19-20 days),respectively,serum and amniotic fluid samples were collected.Urinary iodine and iodine level in the fetal amniotic fluid were measured by As3+-Ce4+ catalytic spectrophotometry.Serum iodine was measured by mild acid digestion method.Results The baseline medians of urinary iodine of LI1 and LI2 groups(5.96,15.92 μg/L) were significantly lower than that of the NI group(43.75 μg/L,all P ＜ 0.01),and the values of HI and HI2 groups(5263.96,20389.64 μg/L) were significantly higher than that of the NI group (all P ＜ 0.01).The median of urinary iodine during pregnancy was significantly lower than that of the baseline of no pregnancy(all P ＜ 0.01).The medians of urinary iodine of the NI group at the first and the second trimesters (28.97,34.34 μg/L) were significantly lower than that of the third trimester(42.31 μg/L,all P ＜ 0.01).The means of serum iodine of LI1 and LI2 groups[(3.68 ± 1.69),(10.45 ± 4.16) μg/L] were significantly lower than that of the NI group [(23.68 ± 3.85)μg/L,all P ＜ 0.05],and the means of serum iodine of HI1 and HT2 groups [(502.67 ± 97.03),(822.15 ± 139.45)μg/L] were significantly higher than that of the NI group (all P ＜ 0.01).Although the mean of serum iodine of HI group gradually decreased with the progression of gestation,the difference was not statistically significant(all P ＞ 0.05).The iodine levels in amniotic fluid of fetal rats at the second and the third trimesters in LI1 group(0.85,3.00 μg/L) were significantly lower than that of the NI group(3.56,7.91 μg/L,all P ＜ 0.01),but the difference was not statistically significant between the iodine level in amniotic fluid of fetal rats of the LI2 and the NI groups at the second and the third trimesters(all P ＞ 0.05).The iodine levels in amniotic fluid of fetal rats at the second and the third trimesters in the HI1 group(49.59,171.21 μg/L) were significantly higher than that of the NI group(all P ＜ 0.01).The iodine levels in amniotic fluid of fetal rats at the second and the third trimesters in HI2 group (98.76,544.77 μg/L) were significantly higher than that of the NI group(all P ＜ 0.01).The iodine level in amniotic fluid of fetal rats in the third trimester was significantly higher than that of the second trimester in all the groups (all P ＜ 0.01).The ratios of serum iodine and urinary iodine of the LI1 and the LI2 groups (1.29 ± 1.14,1.70 ± 1.01) were significantly higher than that of the NI group(0.51 ± 0.37,all P ＜0.01),and that of the HI1 and the HI2 groups(0.21 ± 0.07,0.11 ± 0.07) were significantly lower than that of the NI group (all P ＜ 0.01).The ratios of amniotic fluid iodine and serum iodine of the LI and the LI2 groups (0.19 ± 0.15,0.32 ± 0.17) were significantly higher than that of the NI group(0.13 ± 0.05,P ＜ 0.01),but the difference was not statistically significant between HI1 and HI2 groups(0.09 ± 0.03,0.11 ± 0.04) and NI group(all P ＞ 0.05).The ratio of amniotic fluid iodine and serum iodine of the third trimester was significantly higher than that of the second trimester(all P ＜ 0.05).Conclusions Different iodine intake leads to changes in the levels of maternal iodine metabolism in rats during pregnancy.There probably is a protection mechanism in the mother's body,which protects the mother and the fetal from injury by iodine excess or iodine deficiency.
RESUMO
ObjectiveTo study the mRNA expression of rat Insulin-like growth factors- Ⅰ (IGF- Ⅰ ) and Transforming growth factor-β1 (TGF-β1) in thyroid and placenta with different iodine intakes during pregnancy.MethodsOne hundred and fifty female Wistar rats,weighting 80 - 100 g,were randomly divided into five groups according to body weight,30 rats in each group.Each group was given deionized water containing different concentrations of iodine,50 μg/L(control group,NI),0 μg/L(iodine deficiency 1 group,LI1 ),5 μg/L(iodine deficiency 2 group,LI2),3000 μg/L(iodine excess 1 group,HI1 ),and 10 000 μg/L(iodine excess 2 group,HI2),respectively.After feeding for 12 weeks,the female rats were mated with male rats.The female rats were sacrificed at first(6,7 days),trimester( 12,13 days),and third trimesters( 19,20 days),respectively,then their thyroid and placenta were collected.The mRNA expressions of IGF- Ⅰ and TGF-1 in thyroid and placenta were detected by real-time quantitative PCR.Results①The actual thyroid weights of LI1 and LI2 groups[ (12.17 ± 5.41 ) × 10-2 g,(3.54 ± 1.21) × 10-2 g] were significantly higher than that of NI group[ (2.05 ± 0.50) × 10-2 g,all P ＜ 0.05] ;actual weights of HI1 and HI 2 groups[ (1.64 ± 0.27) × 10-2 g,(1.66 ± 0.29) × 10-2 g] were compared with that of NI group,the difference was not statistically significant(all P ＞ 0.05).②The mRNA expression of IGF- Ⅰ: at the first trimester,LI1 and LI2 groups(l.98 ± 0.35,1.47 ± 0.22) were all higher than that of NI group(1.01 ± 0.18,all P＜ 0.01 ),HI1 and HI2 groups(0.68 ± 0.16,0.75 ± 0.09) were lower than that of NI group(all P ＜ 0.01 );at the second trimester,HI2 group( 1.14 ± 0.17) was lower than that of NI group( 1.58 ± 0.33,P ＜ 0.01 ) ; at the third trimester,LI2 and HI2 groups(1.47 ± 0.20,1.45 ± 0.35) were lower than that of NI group(2.20 ± 0.37,all P＜0.01).The mRNA expression of IGF- I level in NI group at the first,second,and third trimesters(1.01 ±0.18,1.58 ±0.33,2.20 ± 0.37) was up regulated gradually,pairwise comparisons were statistically significant(all P ＜ 0,01 ).③The mRNA expression of TGF-β1: at the first trimester,LI1 group (1.37 ± 0.13) was higher than NI group (1.05 ±0.18,P ＜ 0.01 ),HI1 and HI2 groups(0.50 ± 0.09,0.44 ± 0.11) were lower than NI group(all P＜ 0.01); at the second trimester,LI1 and HI2 groups(1.39 ± 0.28,1.17 ± 0.12) were higher than NI group(0.63 ± 0.22,all P ＜0.01 ) ; at the third trimester,LI1 and LI2 groups ( 1.57 ± 0.30,1.23 ± 0.20) were higher than NI group ( 0.68 ± 0.17,all P＜ 0.01).TGF-β1 mRNA expressions of NI group at the second (0.63 ± 0.22) and third trimesters(0.68 ± 0.17) were lower than that of the first trimester (1.05 ± 0.18,all P ＜ 0.01).④ Rats' IGF-Ⅰ mRNA expression in placental: at the second trimester HI1 group,HI2 group( 1.48 ± 0.16,1.45 ± 0.25) were all higher than the NI group ( 1.00 ± 0.10,all P ＜ 0.01 ) ; at third trimester,HI1 group ( 1.75 ± 0.15 ) were higher than the NI group ( 1.54 ± 0.29,P＜ 0.05),HI2 group(l.94 ± 0.31) were higher than the NI group(P ＜ 0.01 ).IGF- Ⅰ mRNA expression in placental of NI group at the third trimester was higher than the second trimester(P＜ 0.01).⑤ Rats' TGF-β1 mRNA expression in the placenta: at the second trimester and the third trimester of pregnancy there were no significant difference between the five groups(all P ＞ 0.05) ; NI group at the third trimester(0.83 ± 0.16) was lower than the second trimester(0.98 ± 0.20,P ＜ 0.05).Conclusions During pregnancy,IGF- I mRNA expression increases in thyroid under the conditions of iodine deficiency,and this effect is particularly significant in the first trimester; at the same time,TGF-β1 mRNA expression is increased,and this inhibition becomes clear with the deepening of iodine deficiency.Under the condition of iodine excess,the functions of IGF- Ⅰ and TGF-β1 in thyroid above-mentioned were relatively weak.With the development of gestational period,promoting tissues growth and differentiation effect of placenta's IGF- Ⅰ was more significant gradually,but,inhibited effect of TGF-β1 was weaken.
RESUMO
Objective To study the effect of different levels of iodine nutrition on secretion of placental hormone in pregnant rats.Methods Two hundred and twenty five Wistar rats (165 female,60 male),weighing about 80 - 100 g were used in the study.Female rats were randomly divided into five groups according to their body weights:low iodine group Ⅰ(LⅠ),low iodine group Ⅱ (LⅡ),adequate iodine(control) group(Al),high iodine group Ⅰ ( HⅠ ),and high iodine group Ⅱ (H Ⅱ ),and 33 rats in each group.Animals in the low iodine groups were fed low-iodine diet,the iodine content was 13.46 μg/kg,in addition,these rats drank deionized water which containing potassium iodated,the dose was 0 and 5 μg/L,respectively.The rats of adequate and the two high iodine groups were fed normal diet,the iodine content was 22.00 μg/kg,they also drank deionized water,containing potassium iodated 50,3000,and 10000 μg/L,respectively.The rats mated after 3 months of feeding,and were respectively sacrificed at early pregnancy(5 ± 2)d,second trimester( 12 ± 2)d,and third trimester of pregnancy(17 ± 2)d,and then their serum was taken.Serum human chorionic gonadotropin(HCG),human chorionic thyrotropin(HCT),and progesterone were measured by enzyme-linked immunosorbent assay (ELISA).Results In the third trimester,the serum levels of rat HCG were significantly different between groups(F =4.16,P ＜ 0.05).The means of rats serum HCG of the two low iodine groups [ (16.08 ± 4.45),(17.43 ± 2.70)U/L] were significantly higher compared with that of AI group[ (13.68 ± 3.52)U/L] in the third trimester(all P ＜ 0.01 ).In the second and third trimester,the levels of rats serum HCT were significantly different between groups(F =3.59,3.40,all P ＜ 0.05).The means of rats serum HCT of HI group [(70.11 ± 10.97)μU/L] in the second trimester and HII group[(74.93 ± 13.22)μU/L] in the third trimester were higher than those of AI group[ (57.14 ± 12.56),(58.17 ± 8.54)μU/L] significantly(all P ＜ 0.01 ).There were statistical differences of the means of serum progesterone among trimester of pregnancy(F =4.06,4.43,all P ＜ 0.05).The level of serum progesterone of the third trimester[ ( 1462.80 ± 286.48 )pmoL/L] compared to those of the first[ (1929.93 ± 158.37) pmol/L] and the second trimester[ (1856.44 ± 542.08)pmol/L] was decreased significantly(all P ＜ 0.05) in LI group.In the control group,the level of serum progesterone of the second trimester [ (2046.45 ± 475.67)pmol/L ] was significantly higher than the first trimester[ (1714.39 ± 461.71 )pmol/L,P ＜ 0.05 ].Conclusions During pregnancy,placenta could promote HCG secretion under iodine-deficient conditions.In addition,the placenta increases the secretion of HCT under conditions of excess iodine.In the condition of severe iodine deficiency,the secretion of serum progesterone decreases,and further decreases with prolongation of pregnancy,but it is opposite to the change of HCG during pregnancy.This phenomenon could lead to harmful pregnant outcomes easily.