Protective effect of fluoxetine against hypoxia induced injury on PC12 cells / 中国药理学通报

Aim To study the protective effect of fluoxetine against hypoxia induced injury on PC12 cells. Methods PC12 cells were randomly divided into control group, hypoxia group, and fluoxetine hydrochloride group. The last two groups were put into a hypoxic culture chamber for 18 hours, the cell state was observed under inverted microscope, and cell viability was detected using CCK-8 assay. Reactive oxygen species (ROS) level was evaluated by DCFH-DA. Lactate dehydrogenase (LDH), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) in cell culture supernatant were evaluated by enzyme labeling method. The expression levels of Bcl-2, Bax and caspase-3 were determined by Western blot. Results Compared with normal group, hypoxia caused obvious damage to PC12 cells. Fluoxetine hydrochloride at 10

Interaction of amoxicillin and nifedipine mediated by intestinal flora / 药学学报

In this study, the change of intestinal microflora in rat fecal samples after amoxicillin administration was observed. In vitro incubation experiments combined with LC-MS/MS assay were used to test the role of intestinal flora in the metabolism of nifedipine. The effect of changes of intestinal flora was determined after amoxicillin administration on the metabolism of nifedipine. We found that the number and types of intestinal flora decreased after taking amoxicillin. After incubation for 12 h, the results showed that the remaining amounts of nifedipine in the N1 group (nifedipine) and N2 group (amoxicillin + nifedipine) were 0.057 6 and 0.064 8 μmol·L-1, respectively, while the remaining amounts of nifedipine after 24 h of incubation were 0.039 6 and 0.050 4 μmol·L-1, respectively. These results show that the intestinal flora is involved in the metabolism of nifedipine. After administration of amoxicillin, the metabolism of nifedipine was slowed down, the AUC0-t was increased by 39.10%, tmax was advanced by 0.45 h, and the CL was reduced 34.71%. The data suggest that the combination may enhance the therapeutic effect of nifedipine. Therefore, drug-drug interactions mediated by gut microbiota cannot be ignored when combined with antibiotics and nifedipine, one of the important factors affecting drug efficacy.

Advances of studies on effect of drug transporter under hypoxia / 中国药理学通报

Plateau environment has the characteristic of low ox-ygen and low pressure, which leads to a series of physiological changes and affects the process of drug metabolism in the body. Many factors affect the pharmacokinetic parameters, including gastric emptying, blood rheology, cardiopulmonary function, hepatorenal function, cytochrome P450 enzyme and so on. The present study focuses on drug metabolic enzymes, since drug transporter is the key factor that mediates drugs in their entrance to the body through the cell membrane, producing the curative effect. In order to provide the reference to further research on the effect of plateau hypoxia on pharmacokinetics and guide the rational use of drugs, we review in this paper the classification of the transporter, mediated drug substrates, the influence of hypoxia on expression levels of drug transporter substrates and the regulatory mechanism of drug transporter under the condition of hypoxia.

Changes of P-gp expression in rats' small intestine and effects on uptake of levofloxacin after acute exposure to hypoxia / 药学学报

The drug transporter play a key role in the absorption of drugs. Investigation of the changes of drug transporters in response to hypoxia will provide insight into the mechanism of drug absorption. In this study we investigated the mRNA and protein expression of the transporter P-gp after acute hypoxia, and evaluated the effects of P-gp changes on absorption of levofloxacin in the intestine. The relative expression of mRNA and protein were reduced by 50.80% and 71.30% (PP<0.05). These results suggest that hypoxia may decrease the expression of P-gp in the intestine to reduce the excretion of levofloxacin and increase the absorption.

Effect of hypoxia on expressions of MDR1 and MRP2 in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the changes in the physiological parameters and gene expression of two drug efflux transporters MDR1 and MRP2 in the small intestine, liver and kidney of rats exposed to acute hypoxia.</p><p><b>METHODS</b>Eighteen Wistar rats were randomly divided into control group, hypoxia for 24 h group and hypoxia for 72 h group. Blood samples were obtained from the abdominal aorta of the rats after the exposure for analyzing the physiological indexes. The mRNA expressions of MDR1 and MRP2 were determined using Real-Time PCR, and their protein expressions were detected with enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>The physiological parameters of the rats in hypoxia group were significantly changed compared with those in the control group. The expressions of MDR1 and MRP2 mRNA and proteins in the small intestine, liver and kidney were significantly increased in rats with hypoxic exposure than in the control rats (P<0.05 or 0.01). As the hypoxic exposure prolonged, the two transporters showed different patterns of variation in different tissues.</p><p><b>CONCLUSION</b>Acute hypoxia affects the physiological parameters and expression levels of MDR1 and MRP2, thus causing changes in the metabolism of the substrates of the transporters. These changes may play an important role in the pharmacokinetics of drugs at a high altitude.</p>

Expression of plateau adaptation gene of rat tissues after plain acute exposure to high altitude / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To detect the expression of the plateau adaptablity gene(EPAS1, EGLN1 and PPARα) and proteins(HIF-2, PHD2 and PPARα) in rats blood, heart, liver, lung and kidney tissue after the rats exposed to high altitude.</p><p><b>METHODS</b>The Wistar rats were randomly divided into plain group(Shanghai, 55 m), acute exposure to high altitude 3400 m group, acute exposure to high altitude 4300 m group. Blood and organs of rats were collected in 1, 3, 5 days after arrival. Real time PCR and ELISA were used to compare the expression of plateau adaptablity gene and related protein between plain group and high altitude exposure groups.</p><p><b>RESULTS</b>The count of red blood cells, hemoglobin and HCT in high altitude 4300 m were higher than those in plain group. Compared with plain group, the expression of EPAS1 gene in blood, heart, liver and kidney tissue of rats at high altitude increased obviously(all P<0.05); the expression of EGLN1 in the heart, liver, brain and kidney increased, and PPARα gene in the heart, liver and kidney increased(all P<0.05). Compared with plain group, the expression of HIF-2 protein increased significantly at high altitudes in the liver, brain and kidney tissues. PHD2 and PPARα increased in the heart, liver and kidney.</p><p><b>CONCLUSION</b>Plateau adaptive genes(EPAS1, EGLN1 and PPARα) and protein(HIF-2, PHD2 and PPARα) differed in different altitude and different organizations. They might be used as target markers of plateau hypoxia.</p>

Liquid chromatography tandem mass/mass spectrometry for the quantification of fudosteine in human serum without precolumn derivatization

A quantitative analysis method for fudosteine in human serum by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry [HPLC-ESI/MS/MS] was established, which shows high sensitivity and selectivity. The mobile phase composition was 75% 20 mM acetic acid and 25% acetonitril, which was pumped at a flow rate of 0.40 mL/ min. The overall chromatographic run time was approximately 7 min. The autosampler was set with an injection volume of 10 microL. The calibration curve was linear in the concentration range of 0.1-15.0 microg/mL. The coefficient of determination [r] was greater than 0.9998. This method has been fully validated and shown to be specific, accurate and precise. The method was simple, rapid and the sample preparation was minimal. It was successfully applied to the analysis of healthy volunteer

Protective effect and action mechanism of petroleum ether extracts from Saussurea involucrate on brain tissues of hypoxia rats / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the protective effect and action mechanism of petroleum ether extracts from Saussurea involucrate on brain tissues of hypoxia rats under constant pressure and closed conditions.</p><p><b>METHOD</b>The PESI dosage-dependent experiment for hypoxia rats was conducted under constant pressure and closed conditions by intraperitoneally injecting 125, 250, 500 mg x kg(-1) to finalize that the optimum dosage is the high dose of PESI. Afterwards, 90 Wistar rats were randomly divided into the hypoxic model group, the acetazolamide 250 mg x kg(-1) group and the PESI high dose group. Each group was further divided into three subgroups according to different hypoxia times, with 10 rats in each subgroup. Under the same hypoxia and administration conditions, the rats were sacrificed after 0, 3, 6 h respectively. Their brain samples were collected for common pathological observation and immunohistochemical staining of HIF-1alpha. Real-time RT-PCR was used to detect HIF-1alpha, EPO, HO-1 and Caspase-3 gene expressions. And the Western blot assay was adopted to detect HIF-1alpha protein expression.</p><p><b>RESULT</b>The brain tissues of the hypoxia model group were severely damaged with the increase in the hypoxia time. The acetazolamide group and the PESI high does group were damaged in a much lower degree. According to the gene expression and the Western blot assay, high dose of PESI could inhibit HIF-1alpha expression. According to the pure gene expression test, high dose of PESI could increase EPO and HO-1 mRNA expressions, but inhibit Caspase-3 mRNA expression.</p><p><b>CONCLUSION</b>PESI's protective mechanism for brain tissues of hypoxia rats under constant pressure and closed conditions may be related to its effects in inhibiting HIF-1alpha expression, increasing EPO expression and resisting cell apoptosis.</p>

Detection of plasma and urine furosemide based on online enrichment and restricted- access media coupled with high-performance liquid chromatography / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a method based on restricted access media-high performance liquid chromatography for direct online sample injection and detection of plasma and urine furosemide in rats.</p><p><b>METHODS</b>The column of restricted access media was used as the pre-treatment column and a C18 column as the analytical column. The mobile phase of the pre- treatment column was water-methanol (95:5, V/V) with a volume percentage of formic acid of 0.1%. The mobile phase of the analytical column was methanol-water (65:35, V/V) for plasma and methanol-water (55:45, V/V) for urine samples, all containing a volume percentage of formic acid of 0.1% with a flow rate of 1 ml/min. The detection wavelength was 274 nm and the column temperature was maintained at 25 degrees celsius.</p><p><b>RESULTS</b>The calibration curve showed an excellent linear relationship in rat plasma furosemide concentration range of 0.1-3.2 µg/ml (r=0.9995) and in urine concentration range of 0.5-32 µg/ml (r=0.9991). The average recoveries of furosemide at 3 spiked levels ranged from 101.82% to 113.36% for plasma and from 98.75% to 112.27% for urine samples. The detection showed good intra- and inter-day assay precisions and accuracies with the relative standard deviations all below 5%. The pharmacokinetic parameters AUC(0→24) was 6.265 g/(ml·h) with a t(1/2) of 2.447 h and a C(Max) of 1.414 g/ml. The mean cumulative excretory rate of furosemide in the urine of rats over 24 h was 32.50%-39.08%.</p><p><b>CONCLUSION</b>Detection of furosemide in plasma and urine samples using restricted access media-high performance liquid chromatography is simple and efficient and allows direct online injection of the samples.</p>

Effects on the pharmacokinetics of furosemide after acute exposure to high altitude at 4010 meters in rats / 药学学报

The paper is to report the pharmacokinetics of furosemide in rats living at plain area and high altitude. After intragastric administration of furosemide (2.87 mg x kg(-1)), serial blood samples (0.5 mL) were collected by retro-orbital puncture at 0, 20 min, 40 min, 1, 1.5, 2, 3, 4, 6, 8, 12 and 24 h, samples were determined by LC-MS/MS, and plasma concentration-time data were analyzed by DAS 2.0 software to get the related pharmacokinetic parameters. The main pharmacokinetic parameters: area under curve (AUC), mean residence time (MRT), the biological half-life (t1/2) and the peak concentration (C(max)) of furosemide, were significantly increased at high altitude, the time to reach peak concentration (t(max)) and clearance (CL) was significantly decreased. This study found significant changes on the pharmacokinetics of furosemide under the special environment of high altitude. This finding may provide some references for clinical rational application of furosemide at high altitude.

Analysis of hypothalamic-pituitary-adrenal axis function in type 2 diabetic patients with different levels of HbA1C / 中华内分泌代谢杂志

Hypothalamic-pituitary-adrenal(HPA)axis-related factors in patients with type 2 diabetes were studied according to different levels of HbA1C.It showed that HPA axis was normal in HbA1C≤ 7% group[ACTH (18.03±8.39)ng/L,blood cortisol(49.22±8.68)μg/L],hyperactive in 7%11% group with weak feedback regulation[ACTH(26.08±15.41)ng/L,blood cortisol(55.64±24.27)μg/L].These results suggest that HPA axis-related factors in type 2 diabetic patients are different with different grades of glucose metabolic turbulence.

Effects of rat serum containing total flavonoid extract of Epimedium sagittatum on development of osteoblasts / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effects of total flavonoid extract of Epimedium sagittatum (TFE) on the proliferation and differentiation of newborn rat calvarial osteoblasts (ROB).</p><p><b>METHOD</b>TFE was supplemented into the culture medium of ROB at 0. 1, 1, 10 and 100 microg x mL(-1) respectively. The serum of rats administered TFES (SRAT) was also added into the medium in a parallel treatment at 2.5%, 5% and 10% respectively. Their effects on cell proliferation and differentiation was studied by MTT and the analysis of osteogenic differentiation marks.</p><p><b>RESULT</b>TFE had no appreciable and on cell proliferation and differentiation at any concentration. However, 2.5% and 5% SRAT stimulated cell proliferation strongly and, 5% SRAT significantly promoted the maturation and function of osteoblast by improving the alkaline phosphatase activity, osteocalcin secretion, calcium deposition and the number of mineralized nodular structures.</p><p><b>CONCLUSION</b>The metabolites of TFE should be the anti-osteoporosis constitutes of Epimedium sagittatum.</p>

Research on isolation and purification of total iridoid glycosides from herbal Lamiophlomis rotata / 中国中药杂志

<p><b>OBJECTIVE</b>Enriching the hemostatic active part total iridoid glycosides from the aqueous extract of herbal Lamiophlomis rotata.</p><p><b>METHOD</b>First derivative spectrophotometry was used as the detection method and the content of total iridoid glycosides was used as tracking target. The abilities of absorption and anti-absorption of ten different types of macroreticular resin were compared, after being used to absorb the iridoid glycosides from aqueous extract of herbal L. rotata. The best purification process was optimized.</p><p><b>RESULT</b>With the optimized purification process, the content of total iridoid glycosides was 67.53%.</p><p><b>CONCLUSION</b>XDA-1 macroreticular resin has good ability of absorption and anti-absorption for iridoid glycosides and 50% ethanol was the best solvent for anti-absorption. The macroreticular resin could be reused.</p>

Effects of Rehmannia glutinosa oligosaccharides on proliferation of HepG2 and insulin resistance / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effects of Rehmannia glutinosa oligosaccharides (ROS) on the proliferation of HepG2 and insulin resistance.</p><p><b>METHOD</b>The HepG2 cells were divided into control group, rosiglitazone (3.4 mg x L(-1)) treated group and ROS (0.1-30 mg x L(-1)) treated group. The proliferation of HepG2 was detected by MTT method. Insulin resistant HepG2 cells model was induced by high concentration of insulin, then the effects of ROS on glucose consumption in insulin resistant HepG2 cells were investigated.</p><p><b>RESULT</b>In the middle glucose culture medium, the absorbance at 570 nm of HepG2 was increased by high concentration of ROS, and decreased by low concentration of ROS by using MTT method, a concentration-dependent manner. ROS increased glucose consumption in HepG2 cells, and showed a better effect at the dose of 10 mg x L(-1). ROS promoted the glucose consumption in insulin resistance of HepG2 cells, improved the sensitivity of insulin resistance of HepG2 cells to insulin.</p><p><b>CONCLUSION</b>High concentration of ROS can promote the proliferation of HepG2, and however low concentration of ROS inhibits the proliferation of HepG2. ROS can significantly improve insulin resistance of HepG2 cells induced by high insulin.</p>

Effects of Rehmannia glutinosa oligosaccharides on proliferation of 3T3-L1 adipocytes and insulin resistance / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the influence of Rehmannia glutinosa oligosaccharides (ROS) on the proliferation of 3T3-L1 adipocytes and insulin resistance.</p><p><b>METHOD</b>3T3-L1 preadipocytes were cultured, the proliferation of 3T3-L1 preadipocytes was detected by MTT method. Insulin resistant 3T3-L1 adipocytes cell model was induced by dexamethasone and the change of glucose concentration in cell culture was determined after ROS treatment.</p><p><b>RESULT</b>In the high glucose DMEM culture media, MTT method showed that the absorbance at 570nm of 3T3-L1 preadipocytes was increased and that of 3T3-L1 adipocytes was decreased. ROS significantly increased glucose consumption in 3T3-L1 preadipocytes and adipocytes culture in a concentration-dependent manner. ROS improved the sensitivity of 3T3-L1 adipocytes to insulin.</p><p><b>CONCLUSION</b>ROS can promote the proliferation of 3T3-L1 preadipocytes, inhibite the proliferation of 3T3-L1 adipocytes, and also, significantly improve insulin resistance induced by dexamethasone.</p>

The antitumor effects of total-flavonoid from Stellera chamaejasmel / 中国中药杂志

<p><b>OBJECTIVE</b>To study the antitumor effects of total-flavonoid from S. chamaejasmel.</p><p><b>METHOD</b>The in vitro antitumor activity against human cancer cell lines, such as stomach cancer SGC-7901, hepatocarcinoma BEL-7402 and leukemia HL-60, were determined by a MTT and clone formation assay. The in vivo antitumor activity was evaluated by the antitumor bioassay against transplanted mouse solid tumor S180 and H22.</p><p><b>RESULT</b>The total-flavonoid inhibited cell proliferation of human tumor cell lines, and its activities are higher than that of vincristine. The total-flavonoid also showed a lower acute toxicity and the strong antitumor activity against transplanted mouse solid tumor S180 and H22 in vivo showing a positive correlation with the concentration. The inhibitory rates at the dose of 0.10 g x kg(-1) ip against S180 and H22 are 45.64% and 47.59%, respectively.</p><p><b>CONCLUSION</b>The total-flavonoid from S. chamaejasme has antitumor activities in vivo and in vitro.</p>