[Effect of high selenium on insulin signaling pathway PI3K-AKT-mTOR in L02 cells].

OBJECTIVE: To observe the effect of high selenium on insulin signaling pathway PI3K-AKT-mTOR in L02 cells. METHODS: One group of L02 cell was treated with different concentrations of selenomethionine(SeMet, 0.001, 0.0025, 0.005, 0.0075, 0.01, 0.025, 0.05, 0.075 and 0.1µmol/L) for 48 h, then cultured with serum-free medium for 4 h and stimulated with 1 µmol/L insulin for 15 min. The insulin signaling pathway(PI3K-AKT-mTOR) was detected by WB. Another group of L02 cell was treated with the same concentrations of SeMet as above for 48 h. The cell supernatant and lysates were collected for the analysis of SELENOP and GPX1, respectively by WB. RESULTS: The expressions of P-AKT-(Ser-473), P-AKT-(Thr-308), PI3K and mTOR in L02 cells under high-Se were decreased with the increase of SeMet concentration. The expressions of GPX1 and SELENOP were enhanced with the increase of SeMet. CONCLUSION: The insulin signaling pathway, PI3K-AKT-mTOR, was damaged in L02 cell under high-Se stress.

[Study of high selenium interfering with glucose and one-carbon metabolism in hepatocytes in vitro].

OBJECTIVE: To investigate the effects of high selenium environment on the expression of selenoproteins and enzymes related to glucose and one-carbon metabolism in normal human hepatocytes. METHODS: Ten different concentrations of selenomethionine(SeMet, 0, 0.001, 0.005, 0.01, 0.05, 0.1, 0.5, 1, 5 and 10 µmol/L) was added into the normal human hepatocyts and incubated for 48 hours. The expressions of selenoprotein(GPX1 and SELENOP1) and metabolic enzymes(PHGDH, SHMT1, MTHFR and MS) were analyzed by Western blot. RESULTS: When the concentration of SeMet was 0-10 µmol/L, the expression trend of selenoprotein(GPX1 and SELENOP1) is similar, which first increases and then decreases. There is a slight difference between the inflection points of GPX1 and SELENOP1, which are respectively 0.5 µmol/L and 0.1 µmol/L. The expression trend of serine de novo synthesis pathway key enzymes(PHGDH) and folate cycle metabolizing enzymes(SHMT1, MTHFR and MS) is similar to that of selenoproteins, which also increases first and then decreases, but the inflection points are different, which are respectively 0.1 µmol/L(PHGDH and SHMT1) and 0.01 µmol/L(MTHFR and MS). CONCLUSION: Under the high selenium environment, the glycolytic bypass-serine de novo synthesis pathway is activated to synthesize endogenous serine due to the insufficient intracellular serine supply, causing abnormal glucose metabolism, which is an important extension to the hypothesis of the molecular mechanism of high selenium causing IR.

[Intervention study to inhibit the glucose metabolic remodeling in hepatocytes induced by high-selenium in vitro].

OBJECTIVE: To observe the effect of exogenous serine or glycine on the synthesis of selenoprotein and endogenous serine and the expression of metabolic enzymes in hepatocytes cultured with high-selenium in vitro and its dose-response relationship. METHODS: The experiment was divided into two parts, namely a inhibition experiment and a dose-response experiment, using L02 cells as the intervention target. In the inhibition experiment, the blank control group, high-Se(SeMet) group, serine intervention group and high-Se+serine intervention group were set up. Both SeMet and serine were given at a level of 0.05 µmol/L, and the blank control group was given the same volumes of saline. In the dose-response experiment, the concentration of SeMet was 0.05 µmol/L, and the intervention concentration gradients of serine or glycine were 0, 0.05, 0.1, 0.5, 1, 5, 10, 50, 100 and 500 µmol/L. The expression of phosphoglycerate dehydrogenase(PHGDH)、serine hydroxymethyltransferase 1(SHMT1)、methylenetetrahydrofolate reductase(MTHFR)、selenoprotein P(SELENOP) and glutathione peroxidase 1(GPX1)was detected by Western Blot(WB). RESULTS: (1)In the inhibition experiment, compared with the blank control group, the expression of selenium proteins(GPX1 and SELENOP) in L02 cells of the other three groups were significantly increased(P<0.05). Compared with the high expression of PHGDH in L02 cells of high-Se group, the expressions of PHGDH, SHMT1 and MTHFR in high-Se + serine group were significantly decreased(P<0.05). (2) In the dose-response experiment, the expression of PHGDH enzyme in L02 cells gradually decreased with the increase of the concentration of exogenous serine or glycine, showing an obvious dose-dependent effect. In contrast, none of the other metabolic enzymes(SHMT1 and MTHFR) showed similar trends in protein expression. CONCLUSION: The upregulated expression of PHGDH, the key enzyme in the de novo synthesis pathway of serine in hepatocytes cultured with high-selenium can be inhibited feedback by exogenous serine or endogenous serine transformed from exogenous glycine directly.

Dietary mulberry-leaf flavonoids supplementation improves liver lipid metabolism and ovarian function of aged breeder hens.

Mulberry-leaf flavonoids (MF), extracted from mulberry leaves, exert antioxidant and hypolipidemic effects. The purpose of this experimental study was to investigate the effects of dietary MF on the ovarian function and liver lipid metabolism of aged breeder hens. We used 270 (60-weeks-old) Qiling breeder hens randomly assigned in 3 treatments with supplemental dietary MF doses (0, 30, 60 mg/kg). The results showed that dietary MF significantly improved the egg-laying rate, followed by the reduced feed conversion rate (FCR) (p < 0.05). However, there is no obvious difference in hatchability and fertilised eggs hatchability among the three groups (p > 0.05). The level of T-CHO, LDL-C and AKP in serum was reduced, and the HDL-C concentrations were increased by dietary MF (p < 0.05). MF treatment also improved the antioxidant capacity and reduced the apoptotic index of the ovary (p < 0.05). Additionally, dietary MF significantly increased the serum estradiol (E2) levels (p < 0.05) and the transcription level of CYP19A1 and LHR in the ovary (p < 0.05). Dietary MF enhanced fatty acid ß-oxidation in the liver via up-regulating the mRNA expressions of PPARα and CPT-I (p < 0.05). Moreover, the HMF group significantly decreased mRNA expressions of SREBP-1c (p < 0.05) and increased mRNA expressions of ERα, VTG-Ⅱ and ApoB in the liver (p < 0.05). In conclusion, dietary MF could improve the reproduction performance of aged breeder hens through improving ovary function and hepatic lipid metabolism.

Low selenium intake is associated with postpartum weight retention in Chinese women and impaired physical development of their offspring.

The aim of this study was to investigate the association between daily Se intake and postpartum weight retention (PPWR) among Chinese lactating women, and the impact of their Se nutritional status on infants' physical development. Se contents in breast milk and plasma collected from 264 lactating Chinese women at the 42nd day postpartum were analysed with inductively coupled plasma MS. Daily Se intake was calculated based on plasma Se concentration. The dietary data of 24-h records on three consecutive days were collected. Infant growth status was evaluated with WHO standards by Z-scores. Linear regression analyses and multinomial logistic regression were conducted to examine the impact of Se disequilibrium (including other factors) on PPWR and growth of infants, respectively. The results indicated that: (1) the daily Se intake of the subjects was negatively associated with their PPWR (B = -0·002, 95 % CI - 0·003, 0·000, P = 0·039); (2) both insufficient Se daily intake (B = -0·001, OR 0·999, 95 % CI 0·998, 1·000, P = 0·014) and low level of Se in milk (B = -0·025, OR 0·975, 95 % CI 0·951, 0·999, P = 0·021) had potential associations with their infants' wasting, and low level of Se in milk (B = -0·159, OR 0·853, 95 % CI 0·743, 0·980, P = 0·024) had a significant association with their infants' overweight. In conclusion, the insufficient Se nutritional status of lactating Chinese women was first found as one possible influencing factor of their PPWR as well as low physical development of their offspring.

[Study of selenomethionine on the selenoproteins expression in hepatocyte L02 and the synergistic effect of serine].

OBJECTIVE: To observe the effect of selenomethionine(SeMet)on the selenoproteins expression in hepatocyte L02 and the synergistic effect of serine. METHODS: The L02 cells were cultured and divided into SeMet group and Serine+SeMet group. SeMet dose was set as 0. 001, 0. 01, 0. 1, 1 and 10 µmol/L. Serine and SeMet were mixed according to 2∶1 molar ratio(Serine∶SeMet=2∶1). The L02 cells were cultured for 48 h after SeMet and Serine added. Finally, the cell culture supernatants and homogenates were collected for the selenoprotein P(SEPP)and glutathione peroxidase 1(GPx1)concentrations detection by a double-antibody sandwich enzyme-linked immuno-sorbent assay(ELISA). The expression of SEPP and GPx1 in cell homogenates was detected by western blot(WB). RESULTS: ELISA and WB results showed that GPx1 and SEPP expressions were dose dependent in a low SeMet concentration range, reached their inflection points when SeMet concentration was 1 µmol/L and 0. 1 µmol/L respectively, and began to decrease when SeMet concentration was further increased to 10 µmol/L. WB result showed that serine had a synergistic effect on GPx1 and SEPP expressions as SeMet concentration was 0. 001 µmol/L to 10 µmol/L. CONCLUSION: There was an inflection point in selenium protein synthesis when SeMet acted on normal hepatocyte(L02), the specific mechanism needs to be further explored. Secondly, serine had a synergistic effect on GPx1 and SEPP expressions of SeMet in hepatocyte(L02).

Breast milk selenocystine as a biomarker for selenium intake in lactating women at differential geographical deficiency risk in China.

BACKGROUND AND OBJECTIVES: A reliable biomarker for optimal selenium (Se) intake in lactating women is not currently available. METHODS AND STUDY DESIGN: Daily dietary Se intake in lactating women was calculated from a 24-hour meal record survey for over 3 days. Se levels in plasma and breast milk were measured through inductively coupled plasma mass spectrometry. Plasma selenoprotein P 1 levels and glutathione peroxidase 3 activity were measured using an enzyme-linked immunosorbent assay. Ultra-performance liquid chromatography-tandem mass spectrometry was used to analyze proteinaceous Se species in enzymatically digested breast milk. RESULTS: Dietary Se intakes of lactating women from Liangshan, Beijing, and Enshi were 41.6±21.2 ng/d, 51.1±22.6 ng/d, and 615±178 ng/d, respectively (p<0.05). The Se levels in the blood and breast milk were significantly associated with the dietary Se intake (p<0.05). The proteinaceous Se species in breast milk were SeMet and SeCys2. The levels of SeMet in the lactating women from Liangshan, Beijing, and Enshi were 3.31±2.44 ng Se/mL, 7.34±3.70 ng Se/mL, and 8.99±9.64 ng Se/mL, while that of SeCys2 were 13.7±12.0 ng Se/mL, 35.6±20.9 ng Se/mL, and 57.4±13.2 ng Se/mL, respectively. Notably, the concentration of SeCys2, the metabolite of unstable SeCys, reached a saturation platform, whereas no similar phenomenon were found for the total Se SeMet from Secontaining proteins. CONCLUSIONS: SeCys2 in breast milk is a potential biomarker for determining the optimal Se intake in lactating women.

Protective effects of taurine in traumatic brain injury via mitochondria and cerebral blood flow.

In mammalian tissues, taurine is an important natural component and the most abundant free amino acid in the heart, retina, skeletal muscle, brain, and leukocytes. This study is to examine the taurine's protective effects on neuronal ultrastructure, the function of the mitochondrial respiratory chain complex, and on cerebral blood flow (CBF). The model of traumatic brain injury (TBI) was made for SD rats by a fluid percussion device, with taurine (200 mg/kg) administered by tail intravenous injection once daily for 7 days after TBI. It was found that CBF was improved for both left and right brain at 30 min and 7 days post-injury by taurine. Reaction time was prolonged relative to the TBI-only group. Neuronal damage was prevented by 7 days taurine. Mitochondrial electron transport chain complexes I and II showed greater activity with the taurine group. The improvement by taurine of CBF may alleviate edema and elevation in intracranial pressure. Importantly taurine improved the hypercoagulable state.

The effects of different levels of calcium supplementation on the bone mineral status of postpartum lactating Chinese women: a 12-month randomised, double-blinded, controlled trial.

Increasing dietary Ca intake may prevent the excessive mobilisation of bone mineral in nursing mothers. We aimed to investigate whether higher Ca intake could positively modulate the bone mineral changes in Chinese postpartum lactating women. The study was a 12-month randomised, double-blinded, parallel group trial conducted over 12 months. A total of 150 postpartum women were randomly selected to receive either 40 g of milk powder containing 300 mg of Ca and 5 µg of vitamin D (Low-Ca group) or same milk powder additionally fortified with 300 mg of Ca (Mid-Ca group) or 600 mg of Ca (High-Ca group). Bone mineral density (BMD) for the whole body, the lumbar spine, the total left hip and its sub-regions was measured using dual-energy X-ray absorptiometry. A total of 102 subjects completed the whole trial. The duration of total lactating time was 7·9 (SD 2·8) months on average. The intention-to-treat analysis yielded the following mean percentage changes in BMD for the whole body, the lumbar spine and the total left hip, respectively: -0·93 (SD 1·97), 2·11 (SD 4·90) and -1·60 (SD 2·65)% for the Low-Ca group; -0·56 (SD 1·89), 2·21 (SD 3·77) and -1·43 (SD 2·30)% for the Mid-Ca group; and -0·44 (SD 1·67), 2·32 (SD 4·66) and -0·95 (SD 4·08)% for the High-Ca group. The differences between the groups were not statistically significant (P: 0·5-0·9). The results of the complete case analysis were similar. In sum, we found no significant differences in the bone mineral changes from baseline to 12 months in postpartum lactating women consuming milk powder fortified with different levels of Ca.

[UPLC-MS / MS for the pharmacokinetics of icariin in rats].

OBJECTIVE: To establish an ultra-performance liquid chromatographytandem mass spectrometry( UPLC-MS / MS) method for the quantification of icariin( ICA), and investigate pharmacokinetics of ICA in rats following multiple oral administration. METHODS: ICA and an internal standard coumestrol( CMT) were extracted from rat plasma using ethyl acetate and separated on a BEH C18( 50 mm × 2. 1mm, 1. 7 µm) column using a gradient mobile phase of acetonitrile containing 0. 1%( V / V)formic acid and water containing 2 mmol / L ammonium formate at a flow rate of 0. 3m L / min. In negative electrospray ionization mode, multiple reaction monitoring of the precursor-product ion transitions of m / z 675. 6→351. 1 for ICA, 267. 0 →211. 1 for CMT was used for the quantification. Plasma was collected after rats were orally administered with ICA at multiple doses of 50 mg / kg. RESULTS: The linear calibration curve was achieved in a concentration range of 0. 5-50 ng / m L with a lower limit of quantification of0. 5 ng / m L. The value of intra- and inter-day precision was less than 11. 3% and accuracy fell in the ranges of 94. 3%-98. 7%. The recovery ranged from 81. 3% to85. 2% and the matrix effects from 94. 3% to 103. 2%. After oral administration of ICA to rats, t1 /2was( 1. 68 ± 0. 29) h, Cmaxwas( 29. 6 ± 5. 3) ng / m L, tmaxwas( 1. 00 ± 0. 00) h, AUC0- twas( 88. 4 ± 13. 9)( h·ng) / m L. CONCLUSION: The method is specific and accurate, suitable for preclinical pharmacokinetics of ICA.

[Determination of free selenomethionine in cow milk by UPLC-MS/MS].

OBJECTIVE: To establish an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the quantification of free selenomethionine (SeMet), and be applied to the quantification of free SeMet in cow milk. METHODS: The analyte was separated on a BEH C18 column (2.1 mm x 100 mm, 1.7 µm) at 40 degrees C with a mobile phase of water: acetonitrile: formic acid (95: 5: 0.1, V/V) , a flow rate of 0.3 mL/min, and an analysis time of 2. 5 min. At positive electrospray ionization mode, multiple reaction monitoring of the precursor-product ion transitions of m/z 198.0 --> 181.1 was used for the quantification. RESULTS: The linear calibration curve was obtained in a concentration range of 0.5 - 100 ng/mL with a lower limit of quantification of 0.5 ng/mL. The value of intra- and inter-day accuracy for SeMet fell in the range of 97.6%-100.6% and 97.7%-99.2%, and value of intra- and inter-day precision 0.53%-4.49% and 1.03%-4.54%. CONCLUSION: The method is specific, sensitive, rapid, and accurate, suitable for the quantification of free SeMet in cow milk.

[Determination of 13 elements in food by microwave plasma-atomic emission spectrometry].

OBJECTIVE: A novel method for quantitative analysis of multi-elements (Ca, Fe, K, Na, Cu, Mn, Zn, Mg, Ni, Sr, Cr, Cd and Co) in food was established by using microwave plasma-atomic emission spectrometry (MP-AES). METHODS: Samples were digested with HNO3 and H2O2 followed by dilution with ultrapure water to 25 mL (g), and then analyzed directly by MP-AES. RESULTS: In the optimal conditions, the linear calibration curve was established for each element, and the linear regression correlation coefficient was more than 0.9999. The limit of detection (LOD) of these multi-elements varied from 0.04 µg/kg to 3.90 µg/kg. The spiked recovery was between 89.8% and 110.4% . The relative standard deviation of precision measurement was between 1.33% and 3.85%. The accurate and reliable results were obtained for validation of the MP-AES method with food reference material according to the standard reference materials (Nist 1549, Nist 1567, Nist 1568 and Nist 1570) and national standard (GBW08501 and GBW10051), and the measured values were in good agreement with the certified values. CONCLUSION: The established method is accurate, simple, fast, reproducible and environmentally friendly.

[Production effect comparison of SEPP and GPx between HepG2 and Hela cells with different selenocompounds].

OBJECTIVE: To compare the effect of several selenocompounds on the productions of SEPP and GPx in HepG2 and Hela cells. METHODS: The cultured HepG2 and Hela cells were divided into the control, Na2SeO3, SeMet and MeSeCys groups. After adding the selected selenocompounds (with the respective concentration 0.01 and 0.1 µmol/L), the experimental groups were then incubated for 48 h and 72 h. Finally, the cell culture supernatants and homogenates were collected for the SEPP and GPx concentrations detection by a double-antibody sandwich enyme-linked immuno-sorbent-assay (ELISA). RESULTS: The SEPP and GPx concentrations in Hela cells treated with 0.1 µmol/L SeMet and MeSeCys were significantly higher than that in the control group (P < 0.05). The SEPP and GPx concentrations in HepG2 cell treated with 0.1 µmol/L selenocompounds were significantly higher than that in Hela cells (P < 0.05). CONCLUSION: HepG2 cells are more beneficial to the production of selenoproteins than Hela cells.

[Tissue distribution of glucuronidated icaritin metabolite in rats].

OBJECTIVE: To establish an ultra-high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS )method for the quantification of glucuronidated icaritin (GICT), and investigate tissue distribution of GICT in rats following a single intraperitoneal administration. METHODS: Acetonitrile was employed to precipitate protein in tissue homogenate after rat tissues were homogenized. The separation was carried out on a BEH C18 column using a gradient mobile phase of acetonitrile, water, ammonium formate and formic acid. The quantification was achieved by the selected reaction monitoring in the negative electrospray ionization mode. Rat tissues were collected for the quantification of GICT after rats were intraperitoneally administered with ICT at a single dose of 10 mg/kg. RESULTS: The calibration curves were linear over the concentration range of 2-200 ng/ml with the lower limit of quantification of 2 ng/ml. The accuracy values at the levels of 5, 80 and 150 ng/ml fell in the range of 93.2-102.9%, and precisions were within 8.9%. CONCLUSION: The UHPLC-MS/MS method was specific and accurate, suitable for the tissue distribution of GICT. GICT was widely distributed in rat's various tissues, in which the content of GICT remained relatively high in kidney and liver, and GICT was reached the highest in tissues at 8 h.

[Quantitative investigation of glucuronidated icaritin metabolite in rats].

OBJECTIVE: To establish an ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS) method for the simultaneous quantification of icairitin(ICT) and its major metabolite glucuronidated icaritin (GICT), and investigate metabolism of ICT in rats following a single intraperitoneal administration. METHODS: ICT, GICT and an internal standard coumestrol (CMT) were extracted from rat plasma using acetonitrile and separated on a C18 column using a gradient mobile phase of acetonitrile, water, ammonium formate and formic acid. In the negative electrospray ionization mode, selected reaction monitoring of the precursor-product ion transitions of m/z 367.1 --> 297.1 for ICT, 543.3 --> 367.1 for GICT and 267.0 - 211.1 for CMT was used for the quantification. Plasma was collected for the determination of ICT and GICT after rats were intraperitoneally administered with ICT at a single dose of 10 mg/kg. RESULTS: The calibration curves were linear over the concentration range of 0.2 - 20 ng/ml for ICT and 2 -200 ng/ml for GICT with the respective lower limit of quantification at 0.2 and 2 ng/ml. The intra- and inter-day accuracy values fell in the range of 95.1 - 103.7%, and precisions were within 10.3%. Recovery and matrix effect were 89.1 - 92.4% and 93.2 - 104.2%, respectively. CONCLUSION: The UHPLC-MS/MS method was specific and accurate, suitable for the metabolism study of ICT. ICT was rapidly metabolized to GICT in rats.

[Taurine inhibited the apoptosis of glial cells induced by hypoxia].

OBJECTIVE: To study the anti-apoptosis effect of taurine on hypoxic glial cells. METHODS: The glial cells were primarily cultured and divided into three groups, the control group, hypoxia group, and hypoxia + taurine group. The hypoxia model was established by putting cells in a tank filled with oxygen-free mixed gas (95% N2, 5% CO2) with oxygen concentration less than 1%. When the hypoxia time (6 hours) was finished, taurine (3 mmol/L) was added to incubate for hypoxia + taurine group. Finally, the glial cells of all groups were collected for FCM and RT-PCR tests after 24 and 48 hours, respectively. RESULTS: The earlier apoptosis rate was (2. 48 ± 0. 92) %, the middle-late apoptosis rate was (2. 97 ± 0. 75) % for 48h hypoxia group, they were significantly higher than the control group (1. 02 ± 0. 44) % (P < 0. 05). The earlier apoptosis rate (1. 39 ± 1. 03) % and middle-late apoptosis rate (1. 62 ± 0. 1) % for 48 h taurine group were significantly lower than the hypoxia group (P <0. 05). The relative expression level of Bax mRNA for hypoxia group increased by five times higher than the control group, and two times than the hypoxia + taurine group (P <0. 05), and that of Bcl-2 mRNA for 48 h hypoxia + taurine group was two times higher than the hypoxia group (P <0. 01). The relative expression levels of HIF-lα mRNA for 24 h and 48 h hypoxia + taurine groups were significantly higher than the hypoxia group (P <0. 01). CONCLUSION: Taurine could obviously inhibited the apoptosis of glial cells induced by hypoxia.

[Effects of dietary wheat gluten level on decreasing plasma homocysteine concentration in rats].

OBJECTIVE: To investigate the effects of different level of casein and wheat gluten on decreasing plasma homocysteine concentration in rats. METHODS: 48 rats of the Wistar were fed with different level of casein (12.5%, 25% and 50%) and wheat gluten (14.5%, 29% and 58%) diets for 14 days, and they were killed by decapitation to obtain blood and livers was subject to analysis the concentration of homocysteine, cysteine and other amino acids, as well as BHMT and CBS activities. RESULTS: Body weight gain in rats fed wheat gluten dietary was significantly less than casein dietary, but food intake was significantly decreased in wheat gluten group with increasing of the protein content. The plasma homocysteine concentration in rats fed wheat gluten was marketly less than casein, however plasma cysteine concentration in wheat gluten was higher than casein group. CONCLUSION: The effects of wheat gluten on plasma homocysteine concentration are mainly depends on the low contents of methionine and high cysteine content, but the low contents of lyscine and threonine are not ignored. The mainly mechanism is that the increased cysteine concentration promot enzyme activities of homocystein metabolism, and increase the consumption of homocysteine.

[Effects of selenium compounds on proliferation, migration and adhesion of HeLa cells].

OBJECTIVE: To explore the effects of methylseleninic acid (MeSeA), selenomethionine (SeMet) and methylselenocysteine (MeSeCys) on proliferation, migration and adhesion of HeLa cells. METHODS: HeLa cells were cultured and treated with MeSeA, SeMet and MeSeCys for 12 - 72 h respectively. MTT assay, healing assay and in vitro cell Matrigel adhesion assay were used to detect the proliferation, migration and adhesion of HeLa cells. RESULTS: Compared to the control group, the proliferation of HeLa cells was remarkably inhibited by MeSeA (P <0. 01). The migration of HeLa cells in MeSeA group was inhibited by 34% (P < 0. 05) and 26% (P < 0. 05) in 4 h and 8 h, respectively. However, the migration of HeLa cells with inhibitions of 18% and 13% was in SeMet group in 4 h and 8 h. The inhibitions of HeLa cell migration in MeSeCys group was 28% (P < 0.05) and 5% in 4 h and 8 h, respectively. In addition, the adhesive function of HeLa cells in the MeSeA group, the SeMet group as well as the MeSeCys group were inhibited by 36% (P < 0. 01), 25% and 49% (P < 0. 01). CONCLUSION: The proliferation and migration of HeLa cell were effectively inhibited by MeSeA, while the adhesive function of HeLa cell was remarkably inhibited by MeSeCys.

[Betaine-enriched beet suppresses hyperhomocysteinemia induced by choline deficiency in rats].

OBJECTIVE: To investigate the dose-dependent effects of beet powder supplementation on hyperhomocysteinemia induced by choline deprivation in rats. Methods 48 rats of the Wistar were fed 25% soybean protein diet (25S), choline deprivation in 25S diets (25SCD) with different betaine levels (0. 05% and 0. 1%) and beet powder levels (4. 12% and 8. 24%) corresponds to betaine levels for 10 days, and they were killed by decapitation to obtain blood and livers was subject to analysis the concentration of homocysteine, cysteine and other amino acids, as well as BHMT and CBS activities. RESULTS: The homocysteine concentration was increased from (11. 8 ± 0. 4) µmol/L to (33. 2 ± 0. 6) µmol/L by choline deprived - 25S diets (P < 0. 05). The choline deprivation-induced enhancement of plasma homocysteine concentration in rats fed 25S diet was significantly suppressed by 0. 10% betaine or 8. 24% beet in a dose dependent manner. Supplementation with betaine or beet significant increased hepatic BHMT activity. CONCLUSION: The results indicated that betaine or beet could completely suppress the hyperhomocysteinemia induced by choline deficiency resulting from stimulating the homocysteine removal by both remethylation and cystathionine formation.

[Inhibition of antisense VEGF gene on the growth of glioma cells BT325].

OBJECTIVE: To investigate the inhibitory effect of antisense VEGF gene on growth of human glioma BT325 and induced apoptosis in cells. METHODS: The pcDNA3.1/anti-VEGF eukaryotic expression vector was constructed and transfected into human glioma BT325. The ELISA assay was used to assess the expression of VEGF gene. Soft agar colony formation, MTT assay and electron microscope were used to evaluate the proliferation, apoptosis and the morphological changes of BT325. RESULTS: Compared with a control group, the level of VEGF expression was significantly decreased and was almost completely suppressed. The amount in soft agar colony at vector group and antisense VEGF gene group were 21 and 2, respectively. The growth of BT325 was significantly inhibited to 38.23% and resulted in the apoptotic morphology by antisense VEGF gene under electron microscope, compared to vector group. CONCLUSION: Antisense VEGF gene inhibited the growth and proliferation, induced cell apoptosis, played an efficient role of anti-cancer in BT325 cells.