[Research of fenvalerate induced neurodevelopmental toxicity by interfering with the action of estrogen].

OBJECTIVE: To investigate the estrogen interference property of fenvalerate in neurodevelopmental toxicity. METHODS: Thirty 4-week-old healthy female ICR mice were randomly divided into 6 groups: sham operation group, ovariectomized control group, ovariectomized with estrogen (10 µg/g) group, ovariectomized with fenvalerate (5 µg/g) group, sham operation with fenvalerate group, and ovariectomized with estrogen and fenvalerate group, with 5 mice in each group. Fenvalerate was injected intraperitoneally once a day for 7 consecutive days. Mice were sacrificed at 24 h after the last exposure to separate the hippocampus. Immunofluorescence was used to detect neuron marker (NeuN) and astrocyte marker (GFAP) in hippocampal CA1, CA3, and DG regions. RESULTS: Compared with the sham operation group (numbers of NeuN-positive cells: CA1 (54.00±1.73), CA3 (59.00 ± 1.73), DG (100.00 ± 4.58)), the sham operation with fenvalerate group (CA1 (37.67 ± 2.08), CA3 (41.33 ± 1.15), DG (80.67±0.58)) and ovariectomized control group (CA1 (44.00 ± 3.00), CA3 (51.00 ± 3.00), DG (83.00 ± 1.72)) showed significant decreases in number of neurons (NeuN-positive cells) in the hippocampus (P < 0.05). Compared with the ovariectomized control group, the ovariectomized with fenvalerate group (CA1 (47.67 ± 3.21), CA3 (49.00 ± 1.73), DG (87.33 ± 4.04)) showed no significant change in number of hippocampal NeuN-positive cells. Compared with the ovariectomized with fenvalerate group (CA1 (47.67 ± 3.21), DG (87.33 ± 4.04)), the sham operation with fenvalerate group and ovariectomized with estrogen and fenvalerate group (CA1 (40.00 ± 1.00), DG (78.67 ± 2.31)) experienced significant decreases in NeuN-positive cells (P < 0.05). Compared with the sham operation group (CA3 (11.00 ± 1.12), DG (10.67 ± 1.15)), the sham operation with fenvalerate group (CA3 (18.67 ± 2.07), DG (16.33 ± 1.53)) showed significant increase in number of astrocytes (GFAP-positive) cells (P < 0.05). Compared with the sham operation with fenvalerate group, the ovariectomized with fenvalerate group (CA3 (12.00 ± 1.00), DG (11.68 ± 1.16)) showed significant decrease in GFAP-positive cells (P < 0.05). Compared with the ovariectomized with fenvalerate group, the sham operation with fenvalerate group and ovariectomized with estrogen and fenvalerate group (CA3 (16.67 ± 2.13), DG (15.38 ± 1.42)) showed significant increases in GFAP-positive cells (P < 0.05). CONCLUSION: The interference with circulating estrogen is an important mechanism underlying the neurodevelopmental toxicity of fenvalerate.

Abelmoschi Corolla non-flavonoid components altered the pharmacokinetic profile of its flavonoids in rat.

AIM: Abelmoschi Corolla is a well-known herbal medicine used for the treatment of chronic renal disease. Flavonoids are the major bioactive ingredients of Abelmoschi Corolla, but some non-flavonoid components also exist in this herb. In order to clarify the influences of non-flavonoid components on the pharmacokinetics profile of the flavonoid fraction from Abelmoschi Corolla (FFA), an investigation was carried out to compare the pharmacokinetic parameters of seven flavonoid components after administration of FFA and after administration of FFA combined with different non-flavonoid fractions. MATERIALS AND METHODS: A selective and sensitive UPLC-MS/MS method was established to determine the plasma concentrations of the seven compounds. Sprague-Dawley rats were allocated to four groups which orally administered FFA, FFA combined with macromolecular fraction (FFA-MF), FFA combined with small molecule fraction (FFA-SF) and FFA combined with MF-SF (FFA-MF-SF) with approximately the same dose of FFA. At different time points, the concentration of rutin (1), hyperoside (2), isoquercitrin (3), hibifolin (4), myricetin (5), quercetin-3'-O-glucose (6), quercetin (7) in rat plasma were determined and main pharmacokinetic parameters including T(1/2), T(max), AUC and C(max) were calculated using the DAS 2.0 software package. The statistical analysis was performed using the Student's t-test with P<0.05 as the level of significance. RESULTS: Flavonoids almost had similar pharmacokinetics profile that were rapidly absorbed, reached the peak concentration at 30-60 min in group A, but the pharmacokinetic profiles and parameters of these flavonoids changed when co-administered with non-flavonoid components. It was found that AUC of five flavonoids but not hibifolin and quercetin in group FFA-SF and group FFA-MF-SF increased (P<0.05) in comparison with group FFA while the tendency was not observed in group FFA-MF. Moreover, seven flavonoids had varying degrees of differences in the pharmacokinetics parameters such as C(max), T(max) and T(1/2) (P<0.05) in group FFA-MF, FFA-SF and FFA-MF-SF by comparison with group FFA. CONCLUSION: These results indicate that non-flavonoid components could improve the bioavailability and delay the elimination of some flavonoids in rat.

Identification of isoquercitrin metabolites produced by human intestinal bacteria using UPLC-Q-TOF/MS.

In this paper, ultraperformance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) and the MetaboLynx™ software combined with mass defect filtering were applied to identity the metabolites of isoquercitrin using an intestinal mixture of bacteria and 96 isolated strains from human feces. The human incubated samples collected for 72 h in the anaerobic incubator and extracted with ethyl acetate were analyzed by UPLC-Q-TOF/MS within 10 min. The parent compound and five metabolites were identified by eight isolated strains, including Bacillus sp. 17, Veillonella sp. 23 and 32 and Bacteroides sp. 40, 41, 56, 75 and 88 in vitro. The results indicate that quercetin, acetylated isoquercitrin, dehydroxylated isoquercitrin, hydroxylated quercetin and hydroxymethylated quercetin are the major metabolites of isoquercitrin. Furthermore, a possible metabolic pathway for the biotransformation of isoquercitrin was established in intestinal flora. This study will be helpful for understanding the metabolic route of isoquercitrin and the role of different intestinal bacteria in the metabolism of natural compounds.

[Identification of the metabolites of Sinisan extract in rat plasma, urine, feces and bile after intragastric administration].

Sinisan is a widely used traditional Chinese medicine (TCM) in treating various diseases; however, the in vivo metabolic profile of its multiple components remains unknown. In this paper, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) was applied to identify the metabolites of Sinisan extract in rat plasma, urine, feces and bile after intragastric administration. Using MS(E) and mass defect filter techniques, 41 metabolites of 10 parent compounds (naringin, naringenin, hesperidin, neohesperidin, liquiritin, liquiritigenin, glycyrrhizic acid, glycyrrhetinic acid, saikosaponin a and saikosaponin d) were detected and tentatively identified. It was shown by our results that these compounds was metabolized to the forms of hydroxylation, glucuronidation, sulfation, glucuronidation with sulfation and glucuronidation with hydroxylation in vivo.