[Kidney-tonifying and abortion preventing effects of Shou Tai Wan by different extration methods on rats].

OBJECTIVE: To explore the Kidney-tonifying and abortion preventing effect of Shou Tai Wan (STW) by different extration methods on the SD Rats' abortion model. METHODS: Applied hydroxycarbamide and mifepristone (RU-486) to establish the abortion model of corpus luteum inhibition due to Kidney deficiency (disease-syndorme combination model) on SD, rats. Treated the model rats with STW formula. Observed the uterus condition and recorded the embryo number and the miscarriage rate of each rat. 4 kinds of extractions including water extract of STW (A liquid), alcohol extract of STW (B liquid), after the ethanol water extract residue of STW (C liquid) and B + C liquid. Visual observed the uterine lesions embryos and calculated obortion rate. Used chemluninescence methed to cheek the serum estradiol (E2) and progesterone (P) level. Used quantitative RT-PCR (qRT-PCR) to analyze the different of the PR mRNR between the model group and the treated group. RESULTS: Compared with the model group, the abortion rate of B + C liquid was greatly deduced and the embryo number of B + C liquid group, the E2 and P levels were obviously increased in the treated groups. CONCLUSION: STW (B + C) has the best effect of tonifying the kidney and preventing abortion.

Protection of chronic renal failure by a polysaccharide from Cordyceps sinensis.

A water-soluble polysaccharide (CPS-2), isolated from the cultured Cordyceps sinensis, was obtained by hot-water extraction, anion-exchange and gel permeation chromatography. Its structural characteristics were investigated by PMP pre-column derivation, periodate oxidation, methylation analysis, FTIR and NMR spectroscopy. CPS-2 was found to be mostly of alpha-(1-->4)-D-glucose and alpha-(1-->3)-D-mannose, branched with alpha-(1-->4,6)-D-glucose every twelve residues on average. CPS-2 had a molecular weight of 4.39x10(4) Da. The protective effect of CPS-2 on the model of chronic renal failure was established by fulgerizing kidney. The changes in blood urea nitrogen and serum creatinine revealed that CPS-2 could significantly relieve renal failure caused by fulgerizing kidney.

Partial purification of a novel insect antidiuretic factor from the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), which acts on Malpighian tubules.

In this study, we report for the first time the presence of an antidiuretic factor in the head of the Colorado potato beetle (Leptinotarsa decemlineata (Say)) which acts directly on Malpighian tubules. Biologically active fractions were isolated from the head and separated using molecular weight filtration and high-performance liquid chromatography (HPLC). The resulting fractions were tested for their antidiuretic activity on single isolated Malpighian tubules. Antidiuretic activity was found in the 25% acetonitrile Sep-Pak fraction and the Cn-2 (3000-10,000 MW) and Cn-3 (<3000 MW) fractions, suggesting that the antidiuretic factor was probably a peptide of 25 to 50 amino acids. The antidiuretic factor was very potent, since after five successive fractionations on two different HPLC columns, a high level of inhibition (63%) of fluid secretion by Malpighian tubules could be observed at low dose (0.14 head-equivalent/microl). The antidiuretic factor isolated from the head of the Colorado potato beetle was not affected by repeated freezing and thawing but was sensitive to heat. The differences observed between the Colorado potato beetle antidiuretic factor and other insect diuretic and antidiuretic factors may indicate the possibility of a novel family of water regulation hormones in insects.

Preparation, purification, and characterization of a reversibly lipidized desmopressin with potentiated anti-diuretic activity.

PURPOSE: . To prepare and characterize a reversibly lipidized dipalmitoyl desmopressin (DPP), and to compare its anti-diuretic efficacy and biodistribution with that of unmodified desmopressin (DDAVP). METHODS: Dithiothreitol (DTT) was used to reduce the intramolecular disulfide bond in DDAVP, and the reduced DDAVP was treated with a thiopyridine-containing disulfide lipidization reagent, Pal-CPD. The product, DPP, was purified by acid precipitation and, subsequently, by size-exclusion chromatography. Reversed-phase HPLC was used to analyze the purity and to evaluate the hydrophobicity of the product. Mass spectrometry was employed to characterize its molecular structure. The biological activity of DPP was demonstrated by the antidiuretic effects in vasopressin-deficient Brattleboro rats. Preliminary pharmacokinetic and biodistribution studies of intravenously injected DDAVP and DPP were carried out in CF-1 mice. RESULTS: DDAVP was readily reduced by a 2-fold molar excess of DTT at 37 degrees C for 0.5 hr. DPP was formed by the reaction of reduced DDAVP with Pal-CPD. Each DPP molecule contains two palmitic acid moieties, which link to the peptide via two disulfide bonds. After acid precipitation and size-exclusion chromatography, the purity was found to be approximately 95%, and the overall yield was 57%. When DPP was administered subcutaneously to Brattleboro rats, the potency of the anti-diuretic activity of DDAVP was enhanced to more than 250-fold. The plasma concentration of intravenously injected DDAVP in mice decreased rapidly during the first 20 min and followed by a slow elimination rate. However, in DPP administered mice, the plasma concentration actually increased in the first 20 min, followed by a slow elimination with a rate similar to that in DDAVP-injected mice. The regeneration of DDAVP was detected in the plasma of mice treated with DPP. Studies of the organ distribution in mice indicated that the liver retention of DPP was longer than that of DDAVP. On the other hand, the intestinal excretion of DPP was significantly less than that of DDAVP. CONCLUSIONS: The 250-fold increase of the anti-diuretic potency in DPP is most likely due to a slow elimination and prolonged tissue retention, together with the regeneration of active DDAVP, in the animals. Our results indicate that reversible lipidization is a simple and effective approach for improving the efficacy of many peptide drugs.