[Changes of P-gp expression in rats' small intestine and effects on uptake of levofloxacin after acute exposure to hypoxia].

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 m RNA and protein were reduced by 50.80% and 71.30%(P < 0.05). In the single-pass intestinal perfusion model, the intestinal wall permeability was increased by 56.16%, 226.00%, 77.74% and 141.00% in the time intervals at 30-60 min, 60-90 min, 90-120 min and 120-150 min although P-gp expression was decreased(P < 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.

Anti-hypoxia Activity of the Novel NO Donor Acetyl Ferulic Isosorbide Mononitrate in Acute High-Altitude Hypoxia Mice.

Nitric oxide (NO) may act as either a pro-oxidant or an antioxidant in biological systems. Previous work has found inhalation of NO improved survival in a high altitude rat model. NO donor isosorbide mononitrate derivants might have a protective effect against hypoxia. We synthesized a series of isosorbide mononitrate derivant compounds to test their anti-hypoxia activities. Normobaric hypoxia and hypobaric hypoxia models were used to study the protective role of NO donor in mice. The results showed isosorbide mononitrate derivants had protective effects in hypoxia mice. Among those compounds, acetyl ferulic isosorbide mononitrate (AFIM) was the most effective. It prolonged the survival time during the normobaric hypoxia test. It decreased malondialdehyde (MDA) and H2O2 in hypobaric hypoxia mice. The antioxidase activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) remained in normal ranges in the AFIM group. As a sign of mitochondrial dysfunction, the activities of ATPase were down regulated in mice under hypobaric hypoxia conditions. AFIM also protected ATPase activities. The protective effects of AFIM might come from a sustained NO supply and the release of acetyl ferulic acid with anti-oxidant activity.

[Expression of plateau adaptation gene of rat tissues after plain acute exposure to high altitude].

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

[Effects and HPA Axis Related Mechanism of Kaixin-San and Danggui-Shaoyao-San on Glucose and Lipid Metabolism in Chronic Stress Rats with High-fat Diet].

OBJECTIVE: To study the effects and potential mechanism of Kaixin-San and Danggui-Shaoyao-San on glucose and lipid metabolism in chronic stress rats fed with high-fat diet. METHODS: 50 male Wistar rats were randomly divided into normal control group (distilled water), high-fat diet with chronic stress group (distilled water), melatonin group(20 mg/kg), Kaixin-San group (445 mg/kg) and Danggui-Shaoyao-San group (3360 mg/kg). All drugs were orally administered. In addition to the normal control group, each group of rats were fed with high-fat, diet. Simultaneously, stress were carried out after drugs administration 1 h daily. The duration was lasted for six weeks. The rat body weight daily was recorded, and the 24 h period urine was collected to detect the level of urine corticosterone (CORT) after three weeks. The level of plasma intraperitoneal glucose tolerance (IVGTT) was detected after six weeks. Finally, rats were executed, and serum fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), insulin (INS), adrenocorticotropic hormone releasing hormone (CRH), adrenocorticotropic hormone (ACTH), CORT and melatonin ( MLT) were determined. The weight of adrenal gland, liver glycogen and muscle glycogen levels were detected. The adrenal gland index, Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and insulin sensitivity index( ISI) were calculated. RESULTS: Compared with normal group, model rats body weight, IVGTT (120 min), plasm CORT were decreased significantly. Serum TG, TC, LDL-C and urine CORT after three weeks were increased significantly. Kaixin-San and Danggui- Shaoyao-San could regulate the above indexes. CONCLUSION: Kaixin-San and Danggui-Shaoyao-San may regulate the activity of HPA axis, and improve glucose and lipid metabolism disorder in model rats by increasing melatonin secretion.

[Chemical Constituents with Anti-hypoxia Activity from Saussurea involucrata].

OBJECTIVE: To investigate the chemical constituents with anti-hypoxia activity from Saussurea involucrata. METHODS: The chemical constituents, isolated and purified by column chromatography from Saussurea involucrata, were identified by several spectroscopic methods. The anti-hypoxic activities of these compounds were examined using the normobaric hypoxic model of mice. RESULTS: Twelve compounds were isolated from petroleum ether extract of Saussurea involucrata and identified as n-octacosane (1), 1-undecanol (2), heptadecan-l-ol(3), heptacosan-1-ol(4), myristicin (5), apiol(6), ß-sitosterol(7), lupeol(8), moslosooflavone (9), mosloflavone (10), negletein(11), and 5, 6-dihydroxy-7, 8-dimethoxyflavone(12). CONCLUSION: All compounds except 7 and 8 are isolated from this plant for the first time. Compound 1, 5 and 8 - 12 can significantly prolong the survival time of hypoxic mice.

[Protective Effect of Saussurea involucrata Alcohol Extract on Liver Mitochondria in Mice Under Hypoxia Condition].

OBJECTIVE: To study the protective effect of Saussurea involucrata alcohol extract on liver mitochondria in mice under hypoxia condition. METHODS: The hypoxia mice model was established, the BALB/c mice were randomly divided into four groups:normal group ,hypoxia model group, positive control group and Saussurea involucrata alcohol extract group. Mice were put into low pressure oxygen chamber and decompressed, adapted to hypobaric hypoxia environment of simulated altitude of 8,000 m for 12 h, and then recovered to normal altitude. The mice were sacrificed and the liver mitochondria was isolated, the mitochondrial membrane potential and the activity of malate dehydrogenase, aconitase, α-ketoglutarate dehydrogenase, pyruvate dehydrogenase and mitochondrial complex I, II and V were measured. RESULTS: Compared with hypoxia model group, Saussurea involucrata alcohol extract protected mitochondrial membrane potential, sustained the activities of aconitase, α-ketoglutarate dehydrogenase, pyruvate dehydrogenase, and mitochondrial complex I, II and V under hypoxia condition. CONCLUSION: Saussurea involucrata alcohol extract can protect the liver mitochondrial function in mice under hypoxia condtion.

[Isolation and identification of nine iridoid glycosides from Lamiophlomis rotata by HPLC combining PDA and MS].

OBJECTIVE: To establish a rapid chromatographic method to separate the iridoid glycosides from Lamioplomis rotata, and to identify the target compounds with PDA and MS. METHODS: Methanol-water gradient elution was used to separate and analyze the target compounds. The fluid fractions were gathered according to the chromatogram and dried with the nitrogen airflow. The mass fractions of the target compounds were determined with RP-HPLC and the structures were identified with PDA and MS. RESULTS: The purity of some compounds exceeded 90% and these 9 compounds were identified as iridoid glycosides, which were Phlorigidoside C (1), Schismoside (2), Sesamoside (3), Shanzhiside methylester (4), 6-O-Acetyl shanzhiside methylester (5), Phloyoside II (6), Penstemoside (7), Loganin (8) and 8-O-Acetyl shanzhiside methylester (9). CONCLUSION: The method is simple and practicable with high efficiency. It can be used to qualitative and quantitative analysis of the 9 iridoid glycosides in Lamiphlomis rotata and its preparations.

[Effect of ethanol extract from Saussurea involucrata on biochemical indicators of simulated high-altitude hypoxia induced mice].

OBJECTIVE: To estimate the effect of ethanol extract from Saussurea involucrata (EES) on biochemical indicators of simulated high-altitude hypoxia induced mice and its mechanism. METHODS: The oxidative stress indicator( MDA content, SOD activity) and metabolism parameters (LD content, LDH activity, ATP content, Na+ -K+ -ATPase and Ca2+ -Mg2+ -ATPase activity) in both brain and heart of the simulated high-altitude hypoxia induced mice were detected. RESULTS: Compared with the model group, the ESS group could significantly increase the activity of SOD and LDH and decrease the content of MDA and LD in both brain and heart, the content of ATP and the activity of Na+ -K -ATPase and Ca2+ -Mg2+ -ATPase were also elevated. CONCLUSION: The results demonstrate that EES can increase the antioxidant ability, decrease the injury of free radical and ease the disfunction of energy metabolism caused by hypoxia.

[Protective effect and action mechanism of petroleum ether extracts from Saussurea involucrate on brain tissues of hypoxia rats].

OBJECTIVE: 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. METHOD: 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. RESULT: 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. CONCLUSION: 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.

The antioxidative effect of a novel free radical scavenger 4'-hydroxyl-2-substituted phenylnitronyl nitroxide in acute high-altitude hypoxia mice.

Acute mountain sickness is caused by sub-acute hypoxia in healthy individuals going rapidly to altitude. Both tissue hypoxia in vitro and whole-body hypoxia in vivo have been found to promote the release of reactive oxygen species. Nitronyl nitroxide can trap free radicals such as ·NO or ·OH, and may therefore be efficient protective agents. This study assessed the ability of nitronyl nitroxide to against acute mountain sickness as a free radical scavenger in acute high-altitude hypoxia mice model. Normobaric hypoxia and hypobaric hypoxia model were used to estimate the protect effects of nitronyl nitroxide against acute mountain sickness. Low pressure oxygen compartment system was used to stimulate high-altitude hypobaric hypoxia environment. Mice in nitronyl nitroxide groups survived longer than acetazolamide group in normobaric hypoxia test. Hydrogen peroxide (H2O2) and malondialdehyde (MDA) increased in both cerebrum and myocardium in vehicle group. The results indicated more radicals were generated during high-altitude hypobaric hypoxia environment. In therapeutic groups H2O2 and MDA were significantly reduced while the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were similar to normal group. These results demonstrated that nitronyl nitroxide was an efficient tissue radical scavenger and a potential protective agent for acute mountain sickness.

5,6-Dihy-droxy-7,8-di-meth-oxy-flavone.

THE TITLE COMPOUND (SYSTEMATIC NAME: 5,6-dihy-droxy-7,8-dimeth-oxy-2-phenyl-chromen-4-one), C17H14O6, is a flavone that was isolated from the petroleum ether-soluble fraction of the rare traditional Chinese medicinal herb Saussurea involucrata. The flavone mol-ecule is almost planar, with a dihedral angle between the planes of the benzo-pyran-4-one group and the attached phenyl group of 1.89 (6)°. The 5-hy-droxy group forms a strong intra-molecular hydrogen bond with the carbonyl group, resulting in a six-membered hydrogen-bonded ring. The 6-hy-droxy group also forms an intra-molecular O-H⋯O contact. In the crystal, the molecules are linked by O-H⋯O and C-H⋯O hydrogen bonds and π-π inter-actions [3.37 (2)-3.39 (2) Å], which build up a three-dimensional network.

Pharmacokinetics of aconitine in rat skin after oral and transdermal gel administrations.

The purpose of this study was to evaluate percutaneous penetration and arrhythmogenic effects of aconitine after transdermal administration, compared with the oral route. Skin penetration of aconitine was tested by a microdialysis technique in rats and in vivo recovery was determined by retrodialysis. After oral and transdermal administration of aconitine, dialysate was sampled at 20 min intervals until the end of the experiment for the determination of concentration of aconitine in skin. Blood samples were collected and analyzed using a validated HPLC-MS/MS method. In addition, we concurrently recorded the electrocardiogram (ECG). The in vivo recovery of aconitine in the skin was calculated to be 39.59%. The C(max) values for aconitine absorbed into the skin after oral and transdermal administration were 1.51 ± 0.53 and 2723.8 ± 848.8 ng/mL, respectively, and within the plasma, 215.86 ± 79.29 and 20.92 ± 3.15 ng/mL. The C(max) value for the plasma concentration of aconitine after oral administration was approximately 10 times higher than with the transdermal route. For oral administration, the ECG revealed various types of arrhythmias at a period of T(max) , which is normal in transdermal gel administration. These results indicate that transdermal aconitine gel is a safe formulation that can deliver the drug in sufficient amounts and safe concentrations to produce therapeutic action in rats.

Simultaneous determination of four shanzhiside methylester derivatives in rabbit plasma by liquid chromatography/tandem mass spectrometry.

A simple and sensitive high-performance liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed and validated for simultaneous determination of shanzhiside methylester and its three derivatives in rabbit plasma. The method showed good linearity and no endogenous material interfered with the marked compounds and internal standard (IS) capatol peaks. Samples were processed by acetonitrile precipitation. Chromatography was performed using a C18 column (150 × 3.9 mm i.d., 4 µm). The mobile phase consisted of methanol and water (60:40, v/v) during a total run time of 7 min. The main mass parent ions and daughter ions pairs (m/z) for monitoring were: shanzhiside methylester, 429.0/267.4; 8-O-acetyl shanzhiside methylester, 470.9/411.3; loganin, 413.2/251.4; phloyoside II, 479.2/281.3; and IS 385.2/203.3. Finally, the method was applied to a pharmacokinetic study of rabbits following intravenous administration of iridoid glycosides extracted from traditional herb Lamiophlomis rotata.

Study on detection of mutation DNA fragment in gastric cancer by restriction endonuclease fingerprinting with capillary electrophoresis.

The DNA fragment detection focusing technique has further enhanced the sensitivity and information of DNA targets. The DNA fragment detection method was established by capillary electrophoresis with laser-induced fluorescence detection and restriction endonuclease chromatographic fingerprinting (CE-LIF-REF) in our experiment. The silica capillary column was coated with short linear polyarclarylamide (SLPA) using nongel sieving technology. The excision product of various restricted enzymes of DNA fragments was obtained by REF with the molecular biology software Primer Premier 5. The PBR322/BsuRI DNA marker was used to establish the optimization method. The markers were focused electrophoretically and detected by CE-LIF. The results demonstrate that the CE-LIF-REF with SLPA can improve separation, sensitivity and speed of analysis. This technique may be applied to analysis of the excision product of various restricted enzymes of prokaryotic plasmid (pIRES2), eukaryote plasmid (pcDNA3.1) and the PCR product of codon 248 region of gastric cancer tissue. The results suggest that this method could very sensitively separate the excision products of various restricted enzymes at a much better resolution than the traditional agarose electrophoresis.

[Effects on the pharmacokinetics of furosemide after acute exposure to high altitude at 4010 meters in rats].

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.

2-[3-Hy-droxy-4-(2-hy-droxy-eth-oxy)phen-yl]-4,4,5,5-tetra-methyl-2-imidazoline-1-oxyl 3-oxide.

In the title compound, C(15)H(21)N(2)O(5), the imidazoline ring displays a twisted conformation. The mean plane of the imidazoline ring makes a dihedral angle of 22.55 (5)° with the benzene ring. In the crystal, O-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules into a layer parallel to the bc plane.

The GR-FKBP51 interaction modulates fear memory but not spatial or recognition memory.

The glucocorticoid receptor (GR) forms a protein complex with FKBP51 that is increased in post-traumatic stress disorder (PTSD) and by fear conditioned learning. Disrupting the GR-FKBP51 complex with a synthetic peptide can block the storage or retrieval of fear conditioned memories, which could be a novel approach to the alleviate fear associated memory in PTSD. However, a potential unacceptable side effect could be the impairment of other types of memory. Thus, we investigated the effect of disrupting the GR-FKBP51 complex on recognition memory using the novel object and displaced object recognition tasks, spatial memory in the Morris water maze, and on social interaction in Crawley's three-chamber social interaction test. We did not observe adverse effects on these other types of memory and conclude that the GR-FKBP51 interaction remains a promising target for treating psychiatric disorders characterized by unwanted aversive memories such as in PTSD.

[A multi-center, randomized, controlled, double blind and double dummy clinical trial of antofloxacin hydrochloride tablet versus levofloxacin tablet for the treatment of acute bacterial infections].

OBJECTIVE: To evaluate the clinical efficacy and safety of antofloxacin hydrochloride tablet for the treatment of acute bacterial infections. METHODS: A multi-center randomized control, double blind and double dummy clinical trial was conducted; levofloxacin tablet was closed as controlled drug. The duration of treatment was 7-14 days in both groups. RESULTS: A total of 719 patients were enrolled in the study, in which 359 patients treated with antofloxacin and 360 patients treated with levofloxacin were included. Three hundred and thirty and 337 patients completed the study and met with all the criteria for per-protocol analysis, respectively. By the end of chemotherapy, the cured rates in per protocol set (PPS) population were 79.7% and 77.4%, the effective rates were 95.2% and 96.7%, and the bacterial clearance were 96.7% and 97.5% for the treating and control group, respectively. The clinical and bacterial efficacy of antofloxacin and levofloxacin was comparable by the analysis of infectious sites. Three hundred and fifty-seven and 356 patients in antofloxacin and levofloxacin groups were evaluated the safety. The drug adverse events occurred both in 10.1%, and drug adverse reactions occurred in 7.8% and 7.9% patients in the two groups. The most common drug adverse reactions were mild gastroenteric symptoms. No QTc prolongation was detected in all the patients. One patient in each group had mild blood glucose increase at the end of therapy, but the glucose returned to normal level without any intervention. No statistic significant difference between the two groups in clinical efficacy and safety was detected (P > 0.05). CONCLUSIONS: Antofloxacin hydrochloride tablet was effective and safe for the treatment of acute bacterial infections.

2-[4-(2-Hy-droxy-eth-oxy)phenyl]-4,4,5,5-tetra-methyl-2-imidazoline-1-oxyl 3-oxide.

In the title compound, C(15)H(21)N(2)O(4), the imidazoline ring displays a twisted conformation. The dihedral angle between the mean plane of the imidazoline ring and the benzene ring is 33.50 (12)°. In the crystal, mol-ecules are connected by O-H⋯O hydrogen bonds, forming a zigzag chain along the c axis. The chains are linked by C-H⋯O and C-H⋯π inter-actions.

2-[2-(2-Hy-droxy-eth-oxy)phen-yl]-4,4,5,5-tetra-methyl-2-imidazoline-1-oxyl 3-oxide.

In the title compound, C(15)H(21)N(2)O(4), the nitronyl nitroxide unit displays a twisted conformation. The crystal structure is stabilized by non-classical C-H⋯O and C-H⋯π hydrogen bonds, which build up a three-dimensional network.