Biocompatible and biodegradable nanoparticles for enhancement of anti-cancer activities of phytochemicals / 中国天然药物

Many phytochemicals show promise in cancer prevention and treatment, but their low aqueous solubility, poor stability, unfavorable bioavailability, and low target specificity make administering them at therapeutic doses unrealistic. This is particularly true for (-)-epigallocatechin gallate, curcumin, quercetin, resveratrol, and genistein. There is an increasing interest in developing novel delivery strategies for these natural products. Liposomes, micelles, nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers and poly (lactide-co-glycolide) nanoparticles are biocompatible and biodegradable nanoparticles. Those nanoparticles can increase the stability and solubility of phytochemicals, exhibit a sustained release property, enhance their absorption and bioavailability, protect them from premature enzymatic degradation or metabolism, prolong their circulation time, improve their target specificity to cancer cells or tumors via passive or targeted delivery, lower toxicity or side-effects to normal cells or tissues through preventing them from prematurely interacting with the biological environment, and enhance anti-cancer activities. Nanotechnology opens a door for developing phytochemical-loaded nanoparticles for prevention and treatment of cancer.

Effect of quercetin exposure during the prepubertal period on ovarian development and reproductive endocrinology of mice / 药学学报

This study is to explore the effects of quercetin (QUE) on the 3 week-old mice ovarian development and relative hormone levels. The 3 week-old mice were exposed to QUE (45, 25, and 5 mg x kg(-1) x hd(-1)) by gavage for 50 days. The estrous cycle during 50 days and the changes of hormone level such as FSH, LH, etc were monitored. Moreover, the ovaries were removed after sacrifice. The organ index was measured, and the ratios of different stages of follicles were analyzed by HE staining. Furthermore, the proportion of PCNA positive cells during all stages was detected by immunohistochemistry. The results showed that QUE could increase body weight of mice and reduce the anogenital distance (AGD) to some extent, and was able to disrupt mice's estrous cycle, but it could not extend or reduce the cycle regularity. It increased ovarian organ index with a dose-dependent manner. The proportion of the primordial follicle and secondary follicles rose obviously, and that of mature follicles', atretic follicles' and corpus luteums' reduced, while primordial follicle had no change. Immunohistochemistry analysis showed that QUE could effectively increase the percentage of proliferating cells in all kinds of follicles. Serum hormone assay showed that there were significant changes of FSH and LH levels. In summary, QUE showed an estrogen-like effect on mice's ovarian development. The weight of ovary, the proportion of all kinds of follicles, the development of ovarian cells and the level of plasma hormone in mice were altered obviously by oral administration of QUE.

Studies on the chemical constituents in the leaves of Cyclocarya paliurus / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the chemical components of the leaves of Cyclocarya paliurus.</p><p><b>METHOD</b>The chemical components were isolated by solvent extraction and column chromatography. The chemical structures were identified on the basis of physic-chemical constant and spectral data.</p><p><b>RESULT</b>Six compounds were isolated and identified as kaempferol(I), quercetin(II), isoquercitrin(III), ellagic acid(IV), daucosterol(V) and cyclocaric acid B(VI).</p><p><b>CONCLUSION</b>Compounds I, II, III and IV were obtained for the first time from this plant.</p>