Pharmacokinetic and tissue distribution profile of curculigoside after oral and intravenously injection administration in rats by liquid chromatography-mass spectrometry.

Curculigoside has an extensive pharmacological activity, including estrogen-like, improving sexual behavior, antiosteoporotic, antioxidant, immunomodulatory and neuroprotective effects. However, few investigations have been conducted about the pharmacokinetics and tissue distribution of curculigoside to better understand its behavior and action mechanism in vivo. Thus, a sensitive and reliable liquid chromatography with mass spectrometry (HPLC-MS) method was established and validated for the quantification of curculigoside in rat plasma and tissue samples. Biological samples were processed with methanol precipitation, and naringin was used as the internal standard. Chromatographic separation was performed on an Agilent XDB-C18 chromatography column (3.0mm×50mm, 1.8µm) with a mobile phase consisting of acetonitrile and 0.1% formic acid. Quantification was performed by selected ion monitoring with m/z 511.1 [M+HCO2](-) for curculigoside and m/z 579.1 [M-H](-) for the internal standard. The validated method was successfully applied to the pharmacokinetic and tissue distribution study of curculigoside in rats. Non-compartmental pharmacokinetic parameters indicated that curculigoside had rapid distribution, extensive tissue uptake, and poor absorption into systemic circulation. The values of absolute bioavailability were 0.38%, 0.22% and 0.27% for oral doses of 100, 200 and 400mg/kg, respectively. The results of the tissue distribution study suggested that curculigoside was distributed into the heart, lung, spleen, intestine, stomach, kidney, thymus, liver, brain, testis, and bone marrow after oral administration of 150mg/kg. In conclusion, the present study may provide a material basis for study of the pharmacological action of curculigoside, and meaningful insights into further study on clinical application.

Is acupuncture a placebo therapy?

Complementary therapies such as acupuncture are suggested to have enhanced placebo effects. Numerous high quality randomized controlled trials found that acupuncture is no better than its placebo control; however, patients in both real and sham acupuncture groups report clinically meaningful symptom improvements. A possible interpretation of these trials is that acupuncture acts entirely by engaging placebo mechanisms. This article provides further evidence supporting that acupuncture might be a potent placebo, and explains how to address major concerns following this suggestion.

[Research progress of phytoestrogens-like chemical constituents in natural medicines].

Phytoestrogens, which can bind with estrogen receptor and produce estrogen-like effects, are a kind of nonsteroidal compound in plant. Phytoestrogens chemically include isoflavones, coumarins, lignans and other compounds. Phytoestrogens are selective estrogen receptor modulator, and have therapeutical effects on breast cancer, prostate cancer, cardiovascular disease, menopausal symptoms, osteoporosis and other disease, however, do not produce stimulatory hyperplasia effects on uterus, mammary glands and other tissues and organs with positive estrogen receptor. Long-term exposure or excessive use of phytoestrogens maybe affects male reproductive system and hematopoietic function of fetus. Some questions need to be further studied, such as evaluation criteria on biological activity, adverse effects, and action mechanism of phytoestrogen. This review covers plant sources, chemical structure, pharmacological activity and safety of phytoestrogens. It will provide a useful reference for intensive research and rational utilization the phytoestrogens.

The Arabidopsis LFR gene is required for the formation of anther cell layers and normal expression of key regulatory genes.

The anther is the male reproductive organ in flowering plants. Although some genes were reported to be involved in anther development, the molecular mechanisms underlying the transcriptional regulation of these genes is unclear. lfr-2 (leaf and flower related-2), the null allele of Arabidopsis thaliana LFR (LEAF AND FLOWER RELATED), was male-sterile. The anthers of lfr-2 plants were defective in sporogenous cell formation, tapetum development, and pollen development. In agreement with these phenotypes, expression studies showed that LFR was expressed in all cell layers of the anther, and that expression was particularly strong in the tapetal cells and pollen grains. Quantitative RT-PCR analysis revealed that LFR is required for the normal transcription of some anther development-related genes, such as AMS, CALS5, and DYT1, MS1 and MS2, and ROXY2. Genetic analysis showed that SPL was epistatic to LFR while LFR was epistatic to DYT1. We propose that LFR may be a crucial component in the regulation of a genetic network that modulates anther development.