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Hui-juan Zhu

Publications and source records attributed to Hui-juan Zhu.

12 recordsLinked to original sources
PubMed2006

[Human pregnane X receptor-mediated transcriptional regulation of cytochrome P450 3A4 by some phytochemicals].

OBJECTIVE: To test the effect on human pregnane X receptor (hPXR)-mediated transcription regulation of CYP3A4 by five selected phytochemicals. METHODS: Transient cotransfection reporter gene assays in HepG(2) cells were performed with the hPXR expression plasmid and the reporter gene plasmid which contains XRE in the promoter of CYP3A4 linked to luciferase. RESULTS: In the dose-effect study, soybean isoflavone, luteolin and curcumin induced the CYP3A4 transcription via PXR in an evident dose-dependent manner, but isorhamnetin and rutin did not. The inducibility of soybean isoflavone, luteolin and curcumin was also increased in concentrations between 1 micromol/L and 50 micromol/L, 24 h after induction, 50 micromol/L soybean isoflavone, luteolin and curcumin exhibited a 5.46-fold, 2.87-fold, and 2.07-fold increase respectively, compared with 0.1% DMSO treated cells. In the time-effect study, 10 micromol/L and 50 micromol/L soybean isoflavone, luteolin and curcumin induced CYP3A4 transcription between 12 h and 48 h, the strongest induction appeared in 48 h. 48 h after induction, 50 micromol/L soybean isoflavone, luteolin and curcumin exhibited a 6.72-fold, 3.24-fold, and 2.13-fold increase respectively, compared with 0.1% DMSO treated cells. CONCLUSION: Three phytochemicals, i.e. soybean isoflavone, luteolin and curcumin stimulate the PXR-mediated transcription of CYP3A4. Isorhamnetin and rutin have no effect on the CYP3A4 transcription via PXR.

Carcinoma, Hepatocellular↗
PubMed2006

[Kaempferol activates human steroid and xenobiotic receptor-mediated cytochrome P450 3A4 transcription].

OBJECTIVE: To investigate whether kaempferol stimulates pregnane X receptor (PXR)-mediated transcription of CYP3A4. METHODS: Transient cotransfection reporter gene assay was performed with PXR expression plasmid and a reporter plasmid containing the XREs in the CYP3A4 gene promoter in HepG(2)cells. RESULTS: Kaempferol activated PXR-mediated transcription of CYP3A4 in a dose, time-dependent manner. In the dose-response study, kaempferol exposure at concentrations of 1.0 x 10(-3), 1.0 x 10(-2), 0.1, 1.0 and 10.0 mol/L for 24 h increased CYP3A4 transcription by (1.31+/-0.27), (1.45+/-0.36), (1.96+/-0.50), (2.90+/-1.07) and (7.93+/-0.75) fold, respectively compared with 0.1% DMSO (P<0.05). The results from time-course study showed that after 48 h exposure 1.0 and 10.0 mol/L of kaempferol enhanced the transcription of CYP3A4 by (3.73+/-1.21) fold and (8.42+/-1.47) fold, respectively. CONCLUSION: Kaempferol may be a human CYP3A4 gene inducer through PXR, and may affect the metabolism of a large number of substrates of CYP3A4 simultaneously taken.

Carcinoma, Hepatocellular↗
PubMed2006

[Effects of kaempferol and quercetin on cytochrome 450 activities in primarily cultured rat hepatocytes].

OBJECTIVE: To observe the effects of kaempferol and quercetin on the activity of cytochrome P450 in rat hepatocytes. METHODS: Primarily cultured rat hepatocytes were exposed to kaempferol or quercetin in concentrations of 0.1, 1, 10 micromol/L for 12 h, 24 h and 48 h. Hepatocytes CYP isoemzymes-erythromycin N-demethylase (ERND) and aminopyrine N-demethylase (ADM) activities were determined by Nash methods. Erythromycin (10 micromol/L) was used as positive control and DMSO(0.1%) as solvent control. RESULTS: Kaempferol and quercetin inhibited ENRD activity in a dose-and time-dependent manner. In dose-response study, the ENRD activities in kaempferol (0.1,1 and 10 micromol/L) treated groups were (0.088+/-0.008), (0.074+/-0.006) and (0.041+/-0.003)micromol/(mg.min(-1)), respectively. ENRD activity in quercetin treated groups at the same concentrations were (0.082+/-0.007), (0.063+/-0.007) and (0.034+/-0.005) micromol/(mg.min(-1)), respectively. In time-courses study, the ENRD activity exposed to 10 micromol/L kaempferol or quercetin for 12 h and 48 h were (0.053+/-0.006) and (0.037+/-0.007) micromol/(mg.min(-1)), or (0.067+/-0.005) and (0.032+/-0.004) micromol/(mg.min(-1)). ADM activity was inhibited only by kaempferol in 10 mol/L at 24 h, but was not significantly altered by quercetin at any concentration tested. CONCLUSION: In the present condition, kaempferol and quercetin act as potential CYP3A4 inhibitors as they can significantly inhibit ENRD in primarily cultured rat hepatocytes.

Aminopyrine N-Demethylase↗
PubMed2006

[Effect of kaempferol on the pharmacokinetics of nifedipine in rats].

OBJECTIVE: To investigate the effect of kaempferol on the pharmacokinetics of nifedipine (NFP) in rats. METHODS: Twenty male SD rats, weighing 220-260 g, were distributed randomly into 4 groups. The animals were fasted, but allowed free access to water for 12 h before the administration of drugs. NFP dissolved in corn oil was administered via gastric intubation to the rats in control group at a dose of 10 mg/kg. Kaempferol was administered orally to the other three groups with dose of 5, 10, 15 mg/kg, respectively, followed by oral administration of NFP 10 mg/kg. Blood samples were collected through tail vein in heparinized plastic microcentrifuge tubes before and after drug administration. The plasma concentration of NFP was monitored with reversed phase high-performance liquid chromatography (RP-HPLC). Nimodipine was used as the internal standard. Statistical data evaluation was performed with Student's t-test and one-way analysis of variances. RESULTS: The maximal plasma concentration (C(max)) of the three treated groups were 0.51, 0.70 and 0.81 microg/ml, respectively. The area under the concentration-time curve (AUC(0-8)) were 1.81, 2.83 and 3.63 microg/(h.ml(-1)), respectively. The C(max), AUC(0-8) and the mean retention time (MRT(0-8)) of NFP were significantly increased by simultaneous oral treatment with kaempferol (P<0.01). On the other hand, there were no significant differences in the mean peak value time in plasma (T(max)) and the elimination half-life (t1/2(ke)) between the control and the treated groups. CONCLUSION: The concomitant oral use of kaempferol with NFP may influence the pharmacokinetic parameters of NFP in rats, which suggests that kaempferol might reduce the first-pass metabolism of NFP.

Animals↗
PubMed2005

[Puberty development of the healthy adolescent girls of Daqing city, Heilongjiang province].

OBJECTIVE: To investigate the process of puberty development of healthy adolescent girls in Northern China. METHODS: 288 adolescent girls of Daqing city, Heilongjiang province, aged 5 to 16, were studied and followed up yearly for four years. The height, weight, fat percentage, second sex characteristics, and the blood levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E(2)) were examined. RESULTS: The mean age of puberty onset of these healthy adolescent girls was 8.5 years +/- 1.1 years. The blood levels of FSH, LH and E(2) were 0.2 mIU/L, 1.1 mIU/L and 0.06 nmol/L respectively (the 95 percentiles were 2.5 mIU/L, 2.3 mIU/L and 0.12 nmol/L respectively). Their mean age of menarche was 12.4 years +/- 1.2 years. The mean age of breast development was 8.8 years +/- 1.1 years. CONCLUSION: The girls in Northern China begin their puberty development at younger ages than reported before.

Adolescent↗
PubMed2005

[Effects of phytoestrogens on gap junctional intercellular communication].

OBJECTIVE: To observe effects of phytoestrogens quercetin (QC), Genistein (GEN), coumestrol (COM), and enterolactone (ENL) on gap junctional intercellular communication (GJIC) in HaCaT cells. METHODS: HaCaT cells were exposed to QC, GEN, COM, and ENL at 0.1, 1.0, 10.0 and 100.0 micromol/L for 24 hours. The effects of phytoestrogens on GJIC were determined by fluorescence redistribution after photobleaching (FRAP) technique of using a laser scanning confocal microscope (LSCM). RESULTS: QC did not affect the GJIC at 0.1-10.0 micromol/L, whereas, GEN, COM, and ENL exhibited inhibition on the GJIC in some extent at 0.1-10.0 micromol/L without showing significant cytotoxicity. The ratio of fluorescence recovery were between 31.77% to 37.06%, which were significantly decreased compared the vehicle control (44.74%). CONCLUSION: The phytoestrogens GEN, COM, and ENL, but not QC, could inhibit the GJIC function in HaCaT cells at concentrations could be reached in human serum in some instance, indicating they could, under certain conditions, be cancer promoters. Therefore, it should be prudent to use these chemicals as pharmaceuticals or dietary supplements.

Cell Communication↗
PubMed2004

[The antiandrogenic effect of dimethachlon and its mechanism].

OBJECTIVE: To evaluate the antiandrogenic effect of heterocyclic fungicide dimethachlon and its mechanism. METHODS: A combination of in vivo and in vitro assays was selected. Hershberger assay was used to determine the antiandrogenic potential of dimethachlon in vivo. Six-week-old castrated male SD rats were administrated once daily for 7 days with testosterone propionate (TP, 100 micro g/d, sc) plus gavage doses of dimethachlon (50, 100 or 200 mg x kg(-1) x d(-1)), or procymidone (150 or 300 mg x kg(-1) x d(-1), positive control), or iprodione (100 mg x kg(-1) x d(-1), positive control), or flutamide (50 mg x kg(-1) x d(-1), positive control). Transcriptional activation assay in vitro was employed to determine the mechanism of antiandrogenic activity of dimethachlon. Human hepatoma liver cells HepG2 were transiently cotransfected with human androgen receptor (AR) expression plasmid and AR-dependent luciferase report plasmid. Transfected cells were exposed to various concentrations of dimethachlon or flutamide with or without dihydrotestosterone to induce the expression of luciferase gene. RESULTS: In Hershberger assay, dimethachlon, as well as other known antiandrogens, caused decrease in weight of androgen dependent organs or tissues. In 200 mg/kg group, the weight of seminal vesicle, ventral prostate, dorsolateral prostate, Cowper's gland, and levator ani plus bulbocavernosus muscles decreased by 57.8%, 44.8%, 43.9%, 30.1%, and 34.1% respectively, but did not decrease in the vehicle control group. The order of their antiandrogenic potencies was: flutamide > procymidone > dimethachlon > iprodione. In transcriptional activation assay, dimethachlon could inhibit dihydrotestosterone-dependent AR activity in transfected HepG2 cells in dose-effect relationship. The inhibiting potency of dimethachlon was about 1/100 of that of flutamide. CONCLUSION: Dimethachlon has antiandrogenic effect, and acts as an AR antagonist. Its antiandrogenic potency is lower than flutamide and procymidone, but higher than iprodione.

Aminoimidazole Carboxamide↗
PubMed2004

[Study on the transcriptional modulation of cytochrome P450 3A4 expression by zearalenone].

OBJECTIVE: To study whether zearalenone (ZEA), a fungal estrogen, can transcriptionally up-regulate the expression of cytochrome 450 3A4 (CYP3A4) transcription by activating human steroid hormone and xenobiotic receptor (SXR). METHOD: Transient cotransfection reporter gene assays were performed with human SXR expression plasmid and a reporter plasmid containing the SXR in the CYP3A4 gene promoter in HepG(2) cells. RESULTS: The transcriptional induction of CYP3A4 by ZEA with a dose, time-dependent manner. ZEA at the concentrations of 0.01, 0.10, 1.00 and 10.00 micromol/L, respectively, could induce CYP3A4 with (1.50 +/- 0.21), (1.66 +/- 0.27), (3.04 +/- 0.82) and (3.96 +/- 1.16) folds, as compared with 0.1% DMSO. Results from a time-dependent study show that 1.00 and 10.00 micromol/L of ZEA for 12 to 48 hours could enhance the transcription of CYP3A4 with (3.69 +/- 1.34) and (5.18 +/- 1.50) folds, and 10.00 micromol/L of ZEA for 48 hours could induce the CYP3A4 gene expression (5.18 +/- 1.50) folds, as compared with 0.1% DMSO by activating human SXR. CONCLUSION: ZEA could induce the expression of the CYP3A4 gene transcription through activating SXR, possibly by affecting the other substrates of the CYP3A4, especially affecting the metabolism of drugs in the body.

Carcinoma, Hepatocellular↗
PubMed2003

[The effects of weight reduction in reversing fatty liver changes in overweight and obese patients].

OBJECTIVE: To study the effects of weight loss on nonalcoholic steatohepatitis (NASH) in obese patients. METHODS: It is a prospective study. Blood biochemical parameters were examined in 220 overweight or obese patients without alcoholic consumption and without detectable HBsAg. Ultrasonographic examination was performed by a fixed doctor. 45 obese patients followed a program of weight loss, including diet restriction, exercise or drug for a trial period of one year. Weight, blood biochemical tests and ultrasonic examination of liver were compared before and after the trial in all the patients. RESULTS: 75.9% of the patients were diagnosed as NASH. Logistic regression analysis revealed that the risk factors of NASH were body mass index (BMI, beta = 0.926, P = 0.021), age (beta = 0.973, P = 0.021), 2-hour postprandial glucose (beta = 0.987, P = 0.012), 1-hour postprandial net insulin in serum (beta = 1.027, P = 0.032), waist circumference (beta = 1.091, P = 0.038)and low density lipoprotein cholesterol (beta = 0.980, P = 0.041). After the treatment, 65.7% of the patients with NASH improved. The level of ALT in these patients decreased significantly (P = 0.040). The improvement of NASH correlated positively with the reduction of BMI (beta = 3.032, P = 0.010), triglycerides (TG, beta = 1.041, P = 0.025) and waist circumference (beta = 1.115, P = 0.029). The decrease of ALT level correlated with the decrease of BMI (beta = 1.165, P = 0.002), TG (beta = 0.986, P = 0.005), waist circumference (beta = 0.736, P = 0.041), and the increase of high density lipoprotein cholesterol (beta = -0.772, P = 0.016). CONCLUSION: NASH is one of the most important complications of obesity. Weight loss is the mainstay of treatment for obese patients.

Adolescent↗
PubMed2003

[Reproductive toxicity of metadoxine in rats].

OBJECTIVE: To study the reproductive toxicity of metadoxine. METHODS: Male and female rats were given metadoxine before pregnancy and early gestation, i.e. to feed metadoxine to male rats for 60 days before copulation and continue feeding during copulation, and feed metadoxine to female rats for 14 days before copulation. RESULTS: No significant toxic effect was observed in the 400 mg/kg group. A few rats showed paralysis of hind leg in the 800 mg/kg group. The dosage of 1 600 mg/kg caused significant paralysis of hind legs, emaciation, and reduced weight gain. In the 1600 mg/kg group, the mating rate of male rats was significantly affected (P < 0.01). In the 800 and 1 600 mg/kg group, fertility of male rats was markedly reduced (P < 0.01). In the 800 mg/kg group, the effect on sperm counts of epididymis of male rats was markedly reduced (P < 0.05). In the 1 600 mg/kg group, testicle weight and body weight ratio and sperm counts of epididymis rate were significantly (P < 0.001) reduced. In the 1 600 mg/kg group, the fertility rate of female rats was remarkably (P < 0.001) reduced. In the 800 mg/kg group, the weight gain of pregnant rats was significantly reduced (P < 0.001). In both the 800 and 1 600 mg/kg groups, the gestation rate was greatly reduced (P < 0.001). In the 800 mg/kg group, mortality rate before nidation (P < 0.001) and average live fetus number were significantly reduced (P < 0.05). In the 400 mg/kg group, the fetal weight was significantly reduced (P < 0.001). In the 800 mg/kg group, body length, tail length, body weight and sternum development of fetal rats were significantly affected (P < 0.001). CONCLUSION: Under the presented experimental conditions, metadoxine has no teratogenic effects on SD rats and the no effect dose is 400 mg/kg. And the no effect dose for the developmental toxicity is less than 400 mg/kg.

Animals↗