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Objective To investigate the expression of MCT8, DCX, SHH and ARC/ARG3. 1 in brain neurons of neonatal rats exposed to thyroid dysfunction in uterus. Methods Wistar pregnant rats were randomly divided into control group and experimental groups that rats were drunk water with 1, 3, or 5 ppm propylthiouracil ( PTU). The thyroid function and morphological changes of PND1 and PND7 were detected. The expression of MCT8, DCX, SHH, ARC/ARG3. 1 protein in cerebral cortex and hippocampus were detected by Western blot or immunohistochemistry. Results (1) The levels of TT4 decreased significantly in PND1 pups of PTU 3 ppm and 5 ppm groups (P＜0.05 or P＜0.01). The TSH levels significantly increased while FT4 levels significantly decreased in pups of PTU 5 ppm group on PND7 ( P＜0. 05). ( 2) The number NV, V, S, and cross-sectional area of thyroid follicles in offspring of PTU groups were significantly higher than those in the control group on postnatal day 1 and 7 (P＜0.05 or P＜0.01, respectively). (3) The expression of MCT8 in cortex and hippocampus gradually increased with the increase dose of PTU on two postnatal days, but there was significant change in PTU 5 ppm group on PND1 ( P＜0.05). The expression of SHH in pup cortex decreased with the increase of PTU exposure dose on PND7. DCX protein expression in the pup cortex on two postnatal days showed an uptrend with the increase of PTU exposure dose. ARC/ARG3.1 protein levels in hippocampal CA1 area of the pups increased significantly in PTU 1 ppm group on PND1 than that in the same-day control group ( P＜0. 05). Conclusion The damaged neurons of neonatal rats exposed to hypothyroidism in utero can be improved with the gradual recovery of thyroid function, but can not be completely restored to normal level.
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Objective To observe the mRNA and protein expression of thyroglobulin (Tg) and thyroid peroxidase (TPO) in each trimester of pregnant and lactating Wistar rats.Methods Ninety-six SPFNAF Wistar rats (84 female and 12 male),weighting 220-260 g were involved.All female Wistar rats were randomly divided into 7 groups according to their body mass via the random number table method:control group,early pregnancy group (7 d),midpregnancy group (14 d),late pregnancy group (21 d),early lactation group (7 d),midlactation group (14 d) and late lactation group (21 d),12 rats in each group.The rats were fed with conventional feed and drank deionized water freely.Female rats of the last 6 groups were mated with male rats.Thyroids were collected on the 7 d,14 d and 21 d of their pregnancy and lactation,respectively.The mRNA expression levels of Tg and TPO were detected by quantitative real-time PCR,and the protein expression levels of Tg and TPO were detected by Western blotting.Results The expression levels of Tg mRNA in thyroid tissue in the control group,early,middle and late pregnancy and early,middle and late lactation (1.05 ± 0.01,3.20 ± 0.23,1.88 ± 0.12,2.69 ± 0.20,1.53 ± 0.19,2.37 ± 0.31,2.23 ± 0.12) were significantly different between groups (F =42.864,P ＜ 0.05),and those of pregnancy and lactation groups were higher than those in the control group (P ＜ 0.05).The expression levels of Tg protein were 0.15 ± 0.01,0.38 ± 0.01,0.32 ± 0.02,0.37 ± 0.01,0.21 ± 0.01,0.35 ± 0.01,0.44 ± 0.01,respectively.The differences between groups were statistically significant (F =232.250,P ＜ 0.05).And those of pregnancy and lactation groups were higher than those in the control group (P ＜ 0.05).The expression levels of TPO mRNA in thyroid tissue in the control group,early,middle and late pregnancy and early,middle and late lactation (0.57 ± 0.01,0.74 ± 0.03,0.78 ± 0.13,1.08 ± 0.10,0.98 ± 0.10,1.00 ± 0.07,0.76 ± 0.05) were significantly different between groups (F =15.448,P ＜ 0.05).And those of pregnancy and lactation groups were higher than those in the control group (P ＜ 0.05).The expression of TPO protein were 0.23 ± 0.01,0.41 ± 0.01,0.72 ± 0.02,0.78 ± 0.01,0.49 ± 0.01,0.52 ± 0.01,0.45 ± 0.02,respectively.The differences between groups were statistically significant (F =563.692,P ＜ 0.05).And those of pregnancy and lactation groups were higher than those in the control group (P ＜ 0.05).Conclusions The mRNA and protein expression levels of TPO and Tg have increased in pregnant and lactating rats.This performance may be raleted to thyroid hormone deficiency and mild hypothyroidism.
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Objective@#To investigate the effect of long-term deep slow-wave sleep deprivation on the gonad axis, sperm abnormality rate, and structure of the testis in male rats and possible mechanisms.@*Methods@#A total of 30 specific pathogen-free male Wistar rats aged 5 weeks were randomly divided into slow-wave sleep deprivation group 1 (SD1 group) , slow-wave sleep and sleep time deprivation group 2 (SD2 group) , and control group, with 10 rats in each group. The flower pot method was used to establish a model of sleep deprivation. In addition to 12-hour sleep deprivation at night, the rats in the SD1 group were given interference once every 24 minutes, and those in the SD2 group were deprived of sleep for 8 minutes every 24 minutes; the rats in the control group were given 12-hour light illumination and then placed in dark environment for 12 hours. All rats were sacrificed by exsanguination from the femoral artery, and the testis, the epididymis, and blood were collected for analysis. Sperm abnormality rate and sperm motility rate were measured, and cauda epididymal sperm counting was performed. ELISA was used to measure the serum levels of testosterone (T) , follicle-stimulating hormone (FSH) , and luteinizing hormone (LH) .@*Results@#Compared with the control group, the SD2 group had a significant increase in organ coefficient of the epididymis (P<0.05) and a significant reduction in sperm motility rate (P<0.05) . There were significant differences between the SD1 group and the SD2 group in the increase in sperm abnormality rate (P<0.05) and the reduction in cauda epididymal sperm count (P<0.05) . The levels of FSH and T tended to increase, and the level of LH tended to decrease. Pathological examination showed degeneration and vacuolization of a small amount of spermatogenic cells in the SD1 group; in the SD2 group, there were significant degeneration, edema, and vacuolization of most spermatogenic cells, some spermatogenic cells were observed in the lumen, and there were no sperms in the lumen.@*Conclusion@#Long-term deep slow-wave sleep deprivation impairs the structure of the testis, affects sperm motility rate and sex hormones, and increases the risk of sperm abnormality.
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Objective To observe and compare the different orthotopic models of papillary thyroid cancer ( PTC) cell lines of RET/PTC1 rearrangement and BRAFV600E mutation in nude mice. Methods Human PTC cell lines TPC-1, BHP5-16 and BHP2-7 were used. The genotypes of RET/PTC1 rearrangement and BRAFV600E mutation were determined by realtime-PCR and DNA sequencing analysis. The cells(2×105) were injected into the thyroid gland of nude mice. The nude mice were executed at 4th, 12th week, and then their thyroid tumors were removed and weighed. The levels of thyroid hormone were detected using chemiluminescent immunoassay. Results Both TPC-1 and BHP2-7 cells were identified as RET/PTC1 rearrangement by real time-PCR, and the expression of RET/PTC1 rearrangement in BHP2-7 cell was higher than that of TPC-1 cell. BRAFV600E mutation was found in BHP5-16 cell by DNA sequencing analysis, but was not found in TPC-1 and BHP2-7 cells. There were different characteristics in three orthotopic nude model groups. Tumorigenic rates of TPC-1 and BHP5-16 groups were 100%, but the growth of tumor was more rapid in BHP5-16 group than that in TPC-1 group, with more weight tumor. The changes of thyroid hormone levels in BHP5-16 group and TPC-1 group were the same, which were normal at 4th week and sharply decreased at 12 th week(P0. 05). Conclusions It showed difference in the orthotopic models of PTC cell lines of RET/PTC1 rearrangement and BRAFV600E mutation in nude mice. BRAFV600E mutation has obvious impacts on increasing tumorigenic rate and promotion of tumor growth in the orthotopic model. It should not be ignored that advanced thyroid tumor will lead to the destruction of thyroid function.
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Objective To introduce a new economical method which can be used for determination of urinary iodine of batch samples with low cost of arsenic trioxide,and decrease environmental pollution.Methods A catalytic spectrophotometry for measuring iodine content in a small volume of urine samples with low cost of arsenic and cerium was established based on the principle of ammonium persulfate digestion As3+-Ce4+ catalytic spectrophotometry.Ninety-six well polypropylene microplate was utilized as digestion and catalysis reaction vessel,conventional laboratory oven was used as a tool to digest and heat,ice plate was used to cool,and the absorbance was read with the Multimode Reader.The accuracy of the new method was evaluated with the current standard method (WS/T 107-2006) by simultaneous determination of urinary iodine of 24 urine samples.Results The linear range of this method was 0-300 μg/L,the linear correlative coefficient (r) was higher than 0.999,and the detection limit was 8.67 μg/L.The coefficient of variations was 2.15％,4.33％ and 3.48％ when measuring urine samples with high,medium and low iodine concentration,respectively.The test results of three national standard urinary iodine samples were all within the given value range and the relative deviation (RD) was-0.16％,1.81％ and-2.82％,respectively.The average recovery of the low concentration was 97.51％,and that of the high concentration was 96.01％.The two methods correlated well (r =0.995,P ＜ 0.01).Conclusions This method greatly reduces the arsenic waste,environmental pollution,consumables and labor.The new method is simple and efficient,accurate and reliable;it is suitable for application as a supplementary method for analyzing urinary iodine of a large number of samples.
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Objective To investigate the activation of β-sheet breaker peptide H102 on ERK signal transduction pathway in brain of PAP double transgenic mice. Methods PAP double transgenic mice were randomly divided into model group and H102 treatment group (n=10 for each group). A group of C57BL/6J mice with the same genetic background was served as controls. H102 (5.8 mg/kg) 5 μL was infused by intranasal administration to mice in H102 treatment group, and equal volume of blank solution of H102 (chitosan, BSA) was given to mice in control group and model group. The ability of spatial reference memory was tested by Morris water maze after 30 days of treatment. Then immunohistochemistry tests and Western blot technique were used to detect the content of RAS, P-MEK and P-ERK proteins in mouse brain. Results (1) The ability of learning and memory was significantly lower in model group than that of control group. The ability of learning and memory was significantly improved in treatment group than that in model group (P<0.05). (2) The contents of RAS, P-MEK and P-ERK in mouse brain were significantly lower in model group than those of control group, and these protein ex-pressions were significantly increased in treatment group than those in model group (P<0.01). Conclusion β-sheet break-er peptide H102 can activate ERK signal transduction pathway in brain of PAP double transgenic mice, increase PAS, P-MEK and P-ERK levels in nerve cells, and improve the ability of learning and memory in PAP mice.
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Objective To observe the effects of different iodine intake on the thyroid tumor growth and thyroid function in the orthotopic nude mice model of human papillary thyroid carcinoma (PTC) cell line TPC-1.Methods Human PTC cell line TPC-1 (2 × 105) was injected into the left thyroid gland of nude mice.After the operation,the nude mice were randomly divided into three groups:low iodine group (LI),normal iodine group (NI),and high iodine group(HI,50 folds of normal iodine) based on the iodine levels contained in their diet.4 and 12 weeks later,the nude mice were executed,then their thyroid tumors were removed and weighted.The levels of urinary iodine were measured with As3+-Ce4+ catalytic spectrophotometry using ammonium persulfate digestion method.The thyroid hormone level was detected using chemiluminescent immunoassay.The morphology and structure of thyroid tumor tissue was observed by microscope.Results The iodine intervention feeding was successful according to urinary iodine level of LI,NI,and HI groups,paralleled to their iodine intakes.However,the difference of the weight of thyroid tumor in three groups had no statistical significance(P＞0.05).At 4 weeks,compared with control group,the levels of thyroid hormones were normal in NI group,while lower T4 and normal T3 were found in LI group.However,T4 was higher and T3 was lower in HI group (P＜0.05).At 12 weeks,the levels of thyroid hormones all were decreased due to the enlargement of thyroid gland tumor in NI,LI and HI groups.T4 and T3 in LI group were the lowest among three groups,even T4 was below detection limit.T4 was normal and T3 was lower in HI group as compared to control group.Conclusion Iodine intake may not significantly affect tumor growth in the orthotopic nude mice model of human PTC cell line TPC-1,but it has a significant effect on the synthesis of thyroid hormones.
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To explore the relationship between thyroid autoantibodies and thyroid function in school children aged 8-10 years,adults,pregnant women,and lactating women in China,in order to provide reference for the prevention and monitoring of thyroid disease.Healthy 8-10 years old school children (693 cases),adults (698 cases),pregnant women(325 cases),and lactating women(332 cases) from six iodine sufficient areas were enrolled.Serum TSH,FT4,and FT3 were determined by chemiluminescent immunoassay,while antithyroid antibody by radioimmunoassay.The positive rate of thyroid autoantibodies in females was significantly higher than that in the male (5.6％ vs 2.0％ in school children,and 22.8％ vs 3.2％ in adults) ; while positive rate of autoantibodies in pregnant and lactating women (8.9％,8.7％) were significantly lower than that in the other healthy adult women (22.8％).The incidence of abnormal thyroid function in antibody-positive people was higher than that in negative ones in all groups,and abnormal thyroid function showed mainly as subclinical hypothyroidism.In addition,lactating women with negative autoantibodies presented a higher incidence of abnormal thyroid function,mainly as low FT4.The abnormal thyroid function is related with the positive thyroid autoantibodies,indicating that it is essential to follow-up these people with positive antibodies in order to facilitate prevention,early diagnosis,and treatment of thyroid disease.Reference data for thyroid hormones in lactating women should be establisbed as soon as possible.
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Objective To set up the reference range for thyroid hormones and thyrotropin (TSH) of 8-10 years old school children in certain regions of China to provide reference criteria for diagnosis,treatment,and monitoring of thyroid diseases and related research.Methods A cross-sectional survey was conducted in primary school children aged 8-10 years from six iodine sufficient areas.664 normal school children were selected for establishing reference ranges of thyroid hormones and TSH after crucial screening through questionnaire and laboratory investigation.The serum hormone levels were determined by using chemiluminescent immunoassay (Bayer's reagents),and the reference range of each hormone was displayed as its 95％ central interval.Results The reference ranges of TSH,FT4,FT3,TT4,and TT3 were 1.03-8.42 mIU/L,13.44-20.59 pmol/L,4.75-6.96pmol/L,75.29-152.66 nmol/L,and 1.76-3.35 nmol/L,respectively.There was no significant difference in hormone levels between boys and girls.The eight years old group had slightly higher TT4 level compared with the other age groups.The rural children had higher TSH and TT3 levels and lower FT4 level than the urban children.Conclusion The thyroid hormone and TSH levels are substantially different between school children and adults.Therefore,it is necessary to establish the reference range of thyroid function indices for normal school children in order to diagnose,treat,and monitor thyroid diseases.
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ObjectiveTo investigate the effects of maternal thyroid dysfunction during pregnancy caused by iodine deficiency of different degrees on doublecortin ( DCX ) and synaptophysin ( p38 ) expressions in fetal brain.Methods Wistar female rats were randomly divided into four groups:adequate iodine ( AI),mild iodine deficiency ( MiID ),moderate iodine deficiency ( MoID ),and severe iodine deficiency ( SID ),according to the total daily iodine supply( fed on an iodine deficient diet with different dosages of KI added in drinking water).Three months later the rats were mated.Serum TSH and thyroid hormones were determined in maternal rats on gestational day 20 using chemiluminescent immunoassay.The iodine contents in urine and histological changes of thyroid gland were observed in pregnant rats.The mRNA and protein levels of DCX and synaptophysin ( p38 ) were analyzed in fetal brain by using real time quantitative RT-PCR and western blotting respectively.Results( 1 ) Iodine contents in urine of pregnant rats were reduced with the decrease of their iodine supply.Compared with group AI,serum TSH was significantly increased [ ( 2.95 ± 1.70 vs 1.31 ± 0.55 ) mU/L,P ＜ 0.05 ],and both TT4 and FT4 were significantly decreased [ ( 14.3±4.1 vs 28.4±19.3 ) nmol/L,P＜0.05 ] and [ ( 10.8±3.6 vs 20.2±8.0) pmol/L,P＜0.01 ] in pregnant rats of SID group.Whereas,a slight rise in TSH,and a mild decline in both TT4and FT4 were found in MoID and MiID groups.However,there were no significant changes in TT3 and FT3 levels among these four groups.( 2 )Histological characteristics of thyroid gland in pregnant rats showed a typical goiter with small follicular hyperplasia and lack of colloid in SID group,moderate follicular hyperplasia with decreased colloid in MoID group; but mild cellular hyperplasia without decrease in follicular size and colloid in MiID group.( 3 ) The mRNA levels of DCX were increased in fetal brains of three iodine deficiency groups compared with AI group,but a statistical significance was found in MoID group.The protein levels of DCX in all experiment groups were significantly increased.Both mRNA and protein expressions of synaptophysin ( p38 )were significantly down-regulated in three iodine deficiency groups.Conclusions Maternal thyroid dysfunction caused by iodine deficiency,even by mild or moderate iodine deficiency,may lead to retardation of fetal neuronal and synaptic growth.
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Objective To analyze the median urinary iodine(MUI)level in normal pregnant women based on World HeMth Organization(WHO) recommended criterion,and to provide the MUI reference values for monitoring and evaluating iodine nutrition during pregnancy and related studies.Methods Total 604 normal pregnant and 192 non-pregnant women(as a comparison)were selected from a cross-sectional survey.These women were all healthy,iodine sufficient,with normal thyroid function,and negative anti-thyroid antibodies.The iodine content in drinking water,edible salt,and urine was determined by standard methods,and serum TSH,FT4,FT3,thyroid peroxidaseantibody(TPOAb),and thyroglobulin antibody(TgAb)were measured using chemiluminescent immunoassay.Resuits (1)The iodine in drinking water was 3.0μg/L indicating such small amount of iodine could be neglected for daily iodine intake.(2)All women consumed iodized salt with the median iodine in salt of 31.7 mg/kg.The daily iodine intake of at least 240 μg could be roughly estimated if an average of 10 g salt was taken per person per day and further subtracted by 20%iodine lost during cooking,which could meet the iodine needs during pregnancy.(3)The MUI of 173.1μg/L was calculated from 604 pregnant women having 174.5,167.0,and 180.7 μg/L during the first,second,and third trimesters,respectively,reaching the optimal level of 150-249 μg/L recommended by WHO for pregnant women.However,our data showed relatively lower levels,not reaching 200μg/L.The MUI of 240.2μg/L was calculated from 192 non-pregnant women,reaching the level of"above requirement"(200-299μg/L) recommended by WHO for adults.(4)All women were euthyroid and antibody-negative,but the TSH level in pregnant women was lower than that in non-pregnant women,in particular during the first trimester,while FT4 and FT3 were considerably decreased compared with the non-pregnant(with an exception of FT4 in the first trimester),and both gradually declined with the gestational age.Conclusions The optimal MUI level of 150-249 μg/,L recommended by WHO can be applied to pregnant Chinese women,but our data provided a relatively low range of 150-200μ/L throughout pregnancy.The higher MUI of 240.2μg/L in non-pregnant women indicated that iodized salt with different contents should be supplied on market to meet the requirement of different groups of population.
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Objective To study mother and infant's iodine metabolism and thyroid function during lactation with different iodine intakes. Methods Wistar rats were randomly assigned to four groups with severe iodine deficiency (SID), mild iodine deficiency (MiID), normal iodine (NI), and excessive iodine (ExI) intake respectively. All rats were fed on an iodine deficient food and drinking water with different quantities of potassium iodide for 3 months until mating. The urinary iodine, milk iodine, blood iodine, and thyroid hormones (TH) were detected in lactating mother and the offspring rats 14 days after birth. Thyroid weight of mother rats was determined. Thyroid morphology of mother and their offsprings was observed. Results ( 1) Iodine contents in urine, milk, and blood of lactating rats and the offsprings were increased with the increase of iodine supplied in diet. But the change in amplitude between groups was decreased in the other; urine iodine > milk iodine > blood iodine. (2) Serum TT4[ (16. 7±12. 0 vs 36.4±15. 0) nmol/L, P<0.05] was significantly decreased, but TSH [(5.73±2.90vs 1. 38±0.30)mIU/L, P<0.01]and TT3/TT4(6.6±2.7 vs 2. l±0.3,P<0.01) were increased in lactating rats of SID group compared with NI, so as TT4( 10.6±2. 3 vs 16.4±4. 7) nmol/L, P<0.05 ] of offspring rats in SID, but were not in MiID and ExI groups. (3 ) Histological studies showed that small follicular thyroid nodules with follicular hyperplasia occurred in both lactating rats and their offsprings in the SID group, mild swelling in MiID group and polymorphism changes appeared in mother rats of ExI group, but no significant difference appeared in offsprings compared with NI group. Conclusions Severe iodine deficiency will lead to hypothyroidism in mother and infant, but normal iodine nutrition and thyroid function in mother and offspring were maintained through the compensatory action of mother and child in mild iodine deficiency and iodine excess.
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Objective To investigate the sodium iodide symporter (NIS) gene expression during different iodine intakes and its function in thyroid autoregulation. Methods BabL/c mice were randomly divided into five groups according to their different iodine intake levels : low iodine (LI), normal iodine (NI), five-fold iodine (5HI) ,ten-fold iodine (10 HI) and fifty-fold iodine (50 HI). After three months and six months administration, they were sacrificed and thyroids were excised. The mRNA and protein expression level were determined by real time quantitative PCR and immunohistochemistry respectively. Iodine content in thyroid tissue was measured with spectrophotometry and thyroid hormone level was measured with radioimmunoassay. Results Compared with NI group, NIS mRNA and protein expression was greatly increased in LI groups. Immunohistochemistry analysis indicated that NIS was mostly located at the basolateral membrane of thyrocyte,suggesting the improved activity in transporting iodine. But when faced with long-term and severe iodine deficiency, the iodine content in thyroid was finally decreased ,and hormone level lowered. On the other hand, in HI groups NIS mRNA and protein expression was greatly down-regulated. There was a tendency of decreasing NIS gene expression level with increasing doses of iodine intakes. In addition, NIS protein was found mainly in intracellular vesicles, rather than at the cell membrane,suggesting the loss of its activity. The iodine content in thyroid tissue was only slightly increased and was not consistent with the iodine intake levels. Conclusion These findings indicate that NIS may be. regulated at transcription, translation and post-translation levels. This phenomenon constitutes a highly specialized intrinsic autoregulatory system that protects thyroid from high doses of iodine, but at the same time ensures adequate iodine uptake for hormone biosynthesis. NIS plays a critical role in thyroid autoregulation mechanism.
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Objective To set up the trimester-specific reference ranges of thyroid hormones for normal pregnant women to provide reference criteria for diagnosis, treatment and monitoring or screening of thyroid disease during pregnancy and related research. Methods A cross-sectional survey was conducted in pregnant and non-pregnant women in iodine sufficient areas. A total of 505 normal pregnant women and 153 normal non-pregnant women (as control) were selected for establishing trimester-specific reference ranges of thyroid hormones after rigorous screening through the survey questionnaire and laboratory tests. Thyroid hormones were measured by Bayer automated chemiluminescence immunoassay, and the reference range of each hormone was calculated as median (the 50th percentile value) and two-sided limits (the 2.5th and 97.5th percentile values). Results All women investigated were in iodine sufficient status within optimal urine iodine level. The serum TSH level during the 1st trimester was obviously declined compared with that in the non-pregnant individuals (P < 0.01), and started to rise during the 2nd trimester, but was still not restored to non-pregnant level until the 3rd trimester. Serum FT4 and FT3 levels gradually decreased from the 2nd trimester to the 3rd (P < 0.01), and the TT4 and TT3 levels were markedly elevated since early pregnancy (P < 0.01) and reached peak levels at the 2nd trimester approximately making up to 1.5 times of those in the non-pregnant individuals. Conclusion The thyroid hormone levels during pregnancy differ completely from those of the non-pregnant individuals, and also differ during different gestation periods. Therefore, to establish trimester-specific reference data of thyroid hormones during normal pregnancy may be important for clinical practice.
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Objective To study the effects of excessive iodine intake through the meal on the expression of mRNA of placental NIS in pregnant rat and breast NIS in lactating rats. Methods Wistar rats, weaning one month, were randomly divided into three groups according to the body weights, i.e., normal iodine (NI), ten fold high iodine(10HI), one hundred fold high iodine(100HI), the ratio of female and male was 2∶1. Iodine intake of the groups were about 6.15, 61.5 and 615.0 mg/d respectively. After 3 months of treatment, the urine iodine was determined by As-Ce-catalytic spectrophotometry. The rats mated and had offspring. Their placenta and breasts were taken on the seventeenth day of pregnancy and tenth day of lactation respectively. Then NIS mRNA expression was determined by RT-PCR. Results The urine iodine increased with the increase of the iodine intake. The urine iodine and iodine intake showed the parallel magnification. Compared with the NI group,AR value of the placental NIS mRNA in 100HI group and the breast NIS mRNA in 10HI and 100HI group significantly decreased. Conclusion Excessive iodine intake may down-regulate the expression of the placental and breast NIS, which presents a protective effect on offspring.
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Objective To explore the effects of iodine on apoptosis and proliferation of the thyroid cells. Methods Wistar rats of one month wean were randomly divided into five groups(low iodine-LI, normal iodine-NI, fivefold high iodine-5 HI, tenfold high iodine-10 HI, fiftyfold high iodine-50 HI), and fed on water containing different concentration of iodine. All groups got prospective iodine intake, that is 0.6, 6.15, 30.75, 61.5, and 307.5 mg/d. After 7 days, 14 days, 28 days, the rats were sacrificed. The proliferation, apoptosis, and apoptosis related genes expression in the thyroid cells were determined by TUNEL, immunohistochemistry and RT-PCR. Results As for short-term of iodine deficiency, no significant change was seen in the mRNA expression of fas and fasL genes, while in the iodine excess groups,the expreesion showed an up-regulation trend as iodine intake increased. Fas and FasL proteins expressions were consistent in LI and NI groups and all of them were negative or weak positive. In the HI groups the stain density increased with iodine intake and treatmnet period increased. Expression of PCNA was enhanced by short-term iodine deficiency, but not by short-term iodine excess. Apoptosis was not observed in all groups. Conclusion Both short-term iodine deficiency and iodine excess have no obvious effects on thyrocytes apoptosis. Proliferation can be induced by short-term iodine deficiency, not by iodine excess. Wistar rats present a strong tolerance to long-term iodine excess.
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Diabetic nephropathy is one of the most serious microvascular complications, which is related to many growth factors. Growth factors are a kind of cytokines that can stimulate cells to grow, which includes transforming growth factor-? (TGF-?), hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), connective tissue growth factor (CTGF), and so on. Different growth factors can cause glomerular hypertrophy or proliferation, perinephric angiogenesis, tubulointerstitial fibrosis and the like respectively. To know the relationship between the growth factors and diabetic nephropathy could provide a prospective mean to reduce the diabetic mortality rate. This paper reviews the recent researches about the growth factors and diabetic nephropathy to provide a scientific basis for clinical treatment.
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Objective To evaluate the effects of iodine on antioxidative capability by observing activity of antioxidative enzymes and related gene expression, and peroxide content in the brain of rat offspring. Methods One-month weaning Wistar rats were divided into four groups(low iodine-LI, normal iodine-NI, ten-fold high iodine-10HI and fifty-fold high iodine-50HI), and fed with water containing different iodine concentration by adding potassium iodate respectively. Rats mate randomly after three months.The offspring were sacrificed at 28 days after birth, then the activity of SOD and GSH-Px, and MDA content in brain tissue were tested, and the SOD and GSH-Px mRNA expression were measured by RT-PCR. Results Compared with the NI group, only in LI group MDA content were increased significantly (P
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Objective To study the effect of different dosage KIO3 on anti-oxidative capability of the blood.Methods The Wistar rats were randomly divided into 6 groups and given KIO3 through food at different dosages,low iodide(LI),normal iodide(NI),5 fold high iodide(5HI),10 fold high iodide(10HI),50 fold high iodide(50HI)and 100 fold high iodide(100HI).3,6 and 12 months later,the rats were sacrificed and blood glutathione peroxidase(GPx)activity,superoxide dismutase(SOD)activity and malondialdehyde(MDA)content were determined.Results After 3,6 and 12 months of treatment,the GPx activity in LI group was significantly lower than that in NI group.Furthermore,after 12 months of low iodide intake,the SOD activity in LI group was higher than that in NI group.The GPx activity in 100HI group was lower than that in NI group after 3 months of administration,but no difference was seen between these two groups after 6 and 12 months of treatment.No difference was found in the GPx activity of NI group and those of 5HI,10HI and 50HI groups.The SOD activity in 50HI and 100HI groups was higher than that in NI group after 12 months of administration.There was no difference in MDA content among NI group and 4 high iodide groups.Conclusion Low iodide intake may damage the anti-oxidative capability of blood in normal rats.Blood has a strong anti-oxidative ability and compensative capabilities to compete with high iodate intake.
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Objective To study the effect of different iodine intake on the antioxidation of rat thyroid. Methods The rats were divided into 6 groups, low iodide (LI), normal iodine (NI), high iodide including five fold (5HI), ten fold (10HI), fifty fold (50HI), one hundred fold (100HI) and given potassium iodide (KI) at different dosages through food respectively. After 6 and 12 months of treatment, the rats were sacrificed respectively and the activity of glutathione peroxidase (GPx), superoxide dismutase (SOD), the content of malondialdehyde (MDA) in the thyroid were determined. Results The activity of GPx , SOD and the MDA content in LI group were significantly higher than those in NI group. There was no difference in the SOD and GPx activity and MDA content among NI, 5HI and 10HI groups. The MDA content in 50HI group was lower than that in NI group after treated for 12 months, but no difference was found between them after treated for 6 months. Compared with NI group, the GPx activity, SOD activity and MDA content in 100HI group increased after 6 months of treatment, however, decreased after 12 months of treatment. Conclusion Low iodine intake can induce oxidative damage of the thyroid gland in normal rats, high iodine (100 fold) intake for a long period (12 months) may decrease the activity of anti-oxidases in thyroid without obvious oxidative damage, that shows the anti-oxidative system of rat thyroid has a tolerance to high iodine intake.