Determination of a astragaloside IV derivative LS-102 in plasma by ultra-performance liquid chromatography-tandem mass spectrometry in dog plasma and its application in a pharmacokinetic study.

BACKGROUND: Astragalosidic acid (LS-102) is a new water-soluble derivative of astragaloside IV - a major effective component isolated from the Chinese herb Astragali Radix. Our previous study showed that LS-102 exhibited potent cardiovascular activity. PURPOSE: The objective of this study was to investigate the pharmacokinetic properties of LS-102 after single-dose, oral administration in beagle dogs by developing and validating an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. METHOD AND RESULT: The chromatographic separation was performed on a Acquity HSS C18 column (100 mm × 2.1 mm, 1.8 µm) by a gradient elution using a mobile phase consisting of water and acetonitrile at a flow rate of 0.35 ml/min. The analytes were detected with a triple quadrupole tandem mass spectrometry in multiple reaction monitoring mode. Method validation revealed a wide linearity over the range of 2.0-10,000 ng/ml together with satisfactory intra- and inter-day precision, accuracy, and recovery. Stability testing showed that LS-102 spiked into dog plasma was stable for 4 h at room temperature, for up to 2 weeks at -80 °C, and during three freeze-thaw cycles. The method was effectively and successfully applied to the pharmacokinetics of LS-102 after oral administration (5, 10 and 20 mg/kg) to beagle dogs. Peak plasma concentrations are attained within approximately 2 h after oral administration with a half-life ranging from 1.55 h to 4.49 h. The plasma concentration-time curve of LS-102 after oral administration presents the phenomenon of a double-peak absorption phase. The peak concentration and area under the concentration-time curve of LS-102 seemed to increase with the increasing doses proportionally, that suggesting linear pharmacokinetics in dogs. Meanwhile, the doxorubicin (Dox)-injured H9c2 cell model was prepared by incubating the cells in 1 µM Dox for 24 h. MTT assay and LDH release measurement showed that LS-102 protected against Dox-induced cardiomyocyte death. CONCLUSION: The obtained results may help to guide the further pre-clinical research of LS-102 as a potentially novel cardioprotective agent.

Pharmacokinetics Comparison, Intestinal Absorption and Acute Toxicity Assessment of a Novel Water-Soluble Astragaloside IV Derivative (Astragalosidic Acid, LS-102).

BACKGROUND AND OBJECTIVES: Astragaloside IV (AGS IV) is the most important bioactive constituent of Radix Astragali. However, its disappointing clinical application is mainly caused by its very low solubility in biologic fluids, resulting in poor bioavailability after oral administration. We recently obtained a novel water-soluble derivative of AGS IV (astragalosidic acid, LS-102) that displayed significant cardioprotective potential against hypoxia-induced injury. The objective of this study was to investigate the intestinal absorption, main pharmacokinetic parameters and acute toxicity of LS-102 in rodents compared with AGS IV. METHODS: An oral dose of LS-102 and AGS IV (20 mg/kg) was administered to Sprague-Dawley (SD) rats, and blood samples were collected at predetermined time points. The plasma concentrations were detected by a validated UHPLC-MS/MS method, and pharmacokinetic parameters were calculated using a compartmental model. In the intestinal permeability study, the transport of LS-102 across Caco-2 cell monolayers was investigated at six concentrations from 6.25 to 250 µM. Moreover, the acute toxicity of LS-102 (40-5000 mg/kg) via a single oral administration was investigated in BALB/c mice. RESULTS: LS-102 was rapidly absorbed, attaining a maximum concentration of 248.7 ± 22.0 ng/ml at 1.0 ± 0.5 h after oral administration. The relative bioavailability of LS-102 was twice that of AGS IV. LS-102 had a Papp (mean) of 15.72-25.50 × 10-6 cm/s, which was almost 500-fold higher than that of AGS IV, showing that LS-102 had better transepithelial permeability and could be better absorbed in the intestinal tract. The acute toxicity study showed no abnormal changes or mortality in mice treated with LS-102 even at the single high dose of 5000 mg/kg body weight. CONCLUSIONS: Oral LS-102 produced a pharmacokinetic profile different from AGS IV with higher bioavailability, while the toxic tolerance was similar to previous estimates. Thus, we speculated that LS-102 might provide better clinical efficacy and be a potential candidate for the new drug development of Radix Astragali.

Vascular-homing peptides for cancer therapy.

In the past 30 years, a variety of phage libraries have been extensively utilized to identify and develop tumor homing peptides (THPs). THPs specifically bind to tumor cells or elements of the tumor microenvironment while no or low affinity to normal cells. In this regard, the efficacy of therapeutic agents in cancer therapy can be enhanced by targeting strategies based on coupling with THPs that recognize receptors expressed by tumor cells or tumor vasculature. Especially, vascular-homing peptides, targeting tumor vasculature, have their receptors expressed on or around the blood vessel including pro-angiogenic factors, metalloproteinase, integrins, fibrin-fibronectin complexes, etc. This review briefly summarizes recent studies on identification and therapeutic applications of vascular-homing peptides targeting common angiogenic markers or with unknown vascular targets in some certain types of cancers. These newly discovered vascular-homing peptides are promising candidates which could provide novel strategies for cancer therapy.

Crystal structure of 1,7,8,9-tetra-chloro-4-(3,5-di-chloro-benz-yl)-10,10-dimeth-oxy-4-aza-tri-cyclo-[5.2.1.0(2,6)]dec-8-ene-3,5-dione.

In the title compound, C17H11Cl6NO4, the configuration of the cyclo-alkene skeleton is endo,cis. The benzene ring is twisted by 58.94 (8)° from the attached pyrrolidine ring. Two carbonyl groups play a key role in the crystal packing. A short inter-molecular C⋯O distance of 3.017 (3) Šreveals that one carbonyl group is involved in dipole-dipole inter-actions, which link two adjacent enanti-omers into an inversion dimer. Another carbonyl group provides an acceptor for the weak inter-molecular C-H⋯O hydrogen bonds which link these dimers into layers parallel to (011).

Association between the CYP1A2 polymorphisms and risk of cancer: a meta-analysis.

The previously published data on the association between CYP1A2*1C (rs2069514) and CYP1A2*1F (rs762551) polymorphisms and cancer risk have remained controversial. Hence, we performed a meta-analysis to investigate the association between CYP1A2*1F and CYP1A2*1C polymorphisms and cancer risk under different inheritance models. Overall, significant association was observed between CYP1A2*1F and cancer risk when all the eligible studies were pooled into the meta-analysis (dominant model: OR 1.08, 95 % CI 1.02-1.15; heterozygous model: OR 1.06, 95 % CI 1.01-1.12; additive model: OR 1.07, 95 % CI 1.02-1.13). In the further stratified and sensitivity analyses, for CYP1A2*1F polymorphism, significantly increased lung cancer risk and significantly decreased bladder cancer risk were observed in Caucasians. For CYP1A2*1C polymorphism, no significant association was found in overall and all subgroup analyses. In summary, this meta-analysis suggests that CYP1A2*1F polymorphism is associated with lung cancer and bladder cancer risk in Caucasians.

(6,6-Dimethyl-1-phenyl-6,7-di-hydro-5H-pyrrolizin-2-yl)(thio-phen-2-yl)methanone.

In the title compound, C20H19NOS, the pyrrolizine ring is essentially planar (r.m.s. deviation = 0.001 Å) while the fused dihydro-pyrrolizine ring adopts an envelope comformation with the C atom bearing the methyl substituents as the flap. The dihedral angles between the pyrrolizine and the phenyl and thio-phene rings are 34.54 (7) and 44.93 (7)°, respectively. In the crystal, weak C-H⋯O hydrogen bonds link the mol-ecules into infinite zigzag chains parallel to the b-axis direction.

Methyl 3-[(chloro-meth-oxy)carbon-yloxy]-7-hy-droxy-cholan-24-oate.

The title compound, C27H43ClO6, is a derivative of urso-deoxy-cholic acid, in which the OH group at the 3-position is substituted by a chloro-meth-oxy-carbon-yloxy substituent and the carb-oxy-lic acid group at the 24-position is methyl-ated. The A and B rings are cis-fused, while all other rings are trans-fused. In the crystal, two adjacent mol-ecules located along the b-axis direction are inter-locked head-to-tail due to weak C-H⋯O hydrogen bonds. Therefore each mol-ecule is linked to four neighbouring mol-ecules by four C-H⋯O hydrogen bonds, with the OH group at the 7-position and the carbonyl O atom of the ester group acting as the acceptor sites.

Ethyl 2-[6-(4-methyl-benzo-yl)-7-phenyl-2,3-di-hydro-1H-pyrrolizin-5-yl]-2-oxo-acetate.

In the title compound, C25H23NO4, the pyrrolizine ring is approximately planar with an r.m.s deviation from planarity of 0.0053 Å, while the fused di-hydro-pyrrolizine ring adopts an envelope conformation with the C atom connected to two CH2 as the flap. The dihedral angles between the fused ring system and the phenyl and methyl-benzoyl rings are 41.65 (11) and 66.30 (8)°, respectively. In the crystal, weak C-H⋯O hydrogen bonds and C-H⋯π inter-actions occur. One mol-ecule is linked to five adjacent ones through eight hydrogen bonds, forming a three-dimensional network.

[Study on liver injury of Oncomelania hupensis caused by Eomecon chinanthe sanguinarine].

OBJECTIVE: To analyze the effects of Eomecon chinanthe sanguinarine (SAN) on glucogen, enzyme activity and lipid peroxidation of Oncomelania hupensis liver so as to explore the mechanism of SAN against Oncomelania hupensis. METHODS: SAN was extracted and purified from the dry powder of Eomecon chionantha. Oncomelania hupensis were immersed in 5 mg/L sanguinarine (50 Oncomelania hupensis per 500 ml solution) or clean water at 25 degrees C for 36 h, the livers were isolated from live snails. Total glucogen content, malondialdehyde (MDA) level, activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), acid phosphatase (ACP), alkaline phosphatase (AKP), superoxide dismutase (SOD), peroxidase (POD) were determined respectively and the data were analyzed by independent t test. RESULTS: The glucogen content of snail livers in the SAN group and the control group were (12.151 +/- 0.204) and (18.113 +/- 0.163) mg/g respectively, the difference between the two groups was significant (P < 0.05); the MDA levels of the two groups were (5.298 +/- 0.441) and (4.351 +/- 0.197) nmol/mgprot respectively, and the difference was not significant (P > 0.05); the activities of ALT, AST, ACP, AKP, SOD in the SAN group were (2.760 +/- 0.076) U/mgprot, (68.723 +/- 2.295) U/mgprot, (407.949 +/-19.868) U/gprot, (191.287 +/- 0.771) U/ gprot and (48.452 +/- 0.193) U/mgprot respectively, the activities of these enzymes in the control group were (1.104 +/- 0.000) U/mgprot, (49.448 +/- 1.626) U/mgprot, (344.475 +/- 30.186) U/gprot, (121.905 +/- 3.127) U/gprot and (38.814 +/- 2.765) U/mgprot respectively, the activities of ALT, AST, ACP, AKP and SOD were significantly increased after immersed in 5 mg/L SAN for 36 h, the differences were significant (All P values < 0.05); yet the difference of POD between the SAN group [(22.170 +/- 0.018) U/mgprot] and the control group [(21.747 +/- 0.264) U/mgprot] was not significant (P > 0.05). CONCLUSION: SAN can destroy liver functions of Oncomelania hupensis through decreasing glucogen content and changing activities of some important enzymes in snail liver.

2-, 3-, and 4-(1-Oxo-1H-2,3-dihydroisoindol-2-yl)benzoic acids and their corresponding organotin carboxylates: synthesis, characterization, fluorescent, and biological activities.

Three novel organotin complexes with general formula Sn(OH)(bz)(2)L (bz = benzyl, HL = 2-, 3-, or 4-(1-oxo-1H-2,3-dihydroisoindol-2-yl)benzoic acid) and one of their ligands were prepared and characterized. In vitro antifungal and antibacterial activities of these complexes and ligands were investigated with the representative strains of Candida albicans, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Their fluorescence properties have also been discussed.

[Study on differentially expressed gene of the liver of treble fatty metabolism genes mutant mice using cDNA microarray].

OBJECTIVE: To study the gene expression profile of liver of young apoE(-/-)/LDLR(-/-)/Lepr(db/db) treble genes mutant mice and disclose its relationship to hyperlipidemia and the following atherosclerotic lesion. METHODS: The gene expression profile was investigated using cDNA microarray technique; the plasma total cholesterol(TC) and triglyceride(TG) levels were analyzed by COD-PAP and GPO-PAP method. And morphological observations of the aorta were made. RESULTS: Among the 4000 target genes, 92 genes were up-regulated and 105 genes were down-regulated in the treble genes mutants, compared with wild type control. Among the differentially expressed lipid metabolism related genes, cholesterol synthesis gene coding for farnesyl diphosphate farnesyl transferase was down-regulated, while triglyceride metabolism gene e.g. pancreatic lipase related protein 1 gene (Pnliprp1) was up-regulated. Expression profile of carbohydrate, cell skeleton and immune related genes were also altered. On the other hand, in the plasma from the treble genes mutant mice at 5 weeks of age, hyperlipidemia was found to be combined with atheroslerotic lesion. All these biochemical and pathological changes were aggravated following aging. CONCLUSION: The data suggested that the multiple genes mutations, especially those involved in lipid metabolism, were contributing to the alteration of liver gene expression profile that might lead to hyperlipidemia and atherosclerotic lesion in the young apoE(-/-)/LDLR(-/-)/Lepr(db/db) mutants.

[Relationship between anticardiolipin antibodies and abortion].

OBJECTIVE: To explore the relationship between anticardiolipin antibodies (ACA) and abortion. METHODS: The level of serum ACA in 93 abortion women (abortion group) and 80 normal pregnant women (control group) was determined by the enzyme linked immunoabsorbent assay. The abortion group included threatened abortion (n = 62), inevitable abortion (n = 21), and missed abortion (n = 10). RESULTS: The positive rate of ACA in the abortion group was significantly higher than that in the control group (P < 0.05). The positive rate of ACA in pregnant women with a history of abortion was significantly higher than that in those women without a history of abortion (P < 0.05). The positive rate of ACA was not significantly different between habitual abortion and spontaneous abortion (P > 0.05). CONCLUSION: Anticardiolipin antibodies may induce abortion, but it is not related to habitual abortion.