Serum testosterone reduction and metabolism in aging male rats: correlation and mechanism / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the mechanism of serum testosterone reduction, its relationship with metabolism, changes in the number and morphology of Leydig cells and endocrine function in aging male rats.</p><p><b>METHODS</b>The levels of serum total testosterone (tT), LH, FSH, HDL, LDL, TG, TC, Glu, INS, IRG and LP were determined in young (9 mo) and aging rats (12, 15, 18 and 21 mo), with 6 in each group. The morphological changes of Leydig cells were observed under the microscope. The concentrations of testosterone secreted from the cultured Leydig cells with the stimulation of hCG and Forskolin were assayed. The apoptosis rates of Leydig cells were detected by TUNEL. The visceral fat was isolated and weighed, and the Lee's index calculated. All the above indexes were recorded and compared among different age groups.</p><p><b>RESULTS</b>The aging rats showed a significant decrease in the levels of serum tT and TSI ([1.26 +/- 0.65] ng/ml and [0.07 +/- 0.65] ng/mIU) as compared with the young rats ([3.24 +/- 0.38] ng/ml and [0.21 +/- 0.01] ng/mIU) (P < 0.01). Obvious differences were found in the morphology of Leydig cells among different age groups. The T secretion of Leydig cells at 24, 48 and 72 h in aging rats was markedly decreased (P < 0.05) while their TUNEL positive rate remarkably increased in the aging rats (17.36% +/- 1.31%) compared with the young ones (7.02% +/- 1.05%) (P < 0.05). There were statistically significant differences between the young and aging rats in all the biochemical parameters including IRG, HDL, LDL, TG, TC and visceral fat content (P < 0.05), except the levels of serum Glu, INS and LP (P > 0.05).</p><p><b>CONCLUSION</b>The serum T level and secreting capacity of Leydig cells are significantly lower in aging rats than in young ones, and the metabolic parameters undergo regular changes with the decreasing level of serum T. The reduction of testosterone in aging male rats may be associated with the decreased secreting capacity and number of Leydig cells and declined function of the pituitary.</p>

Determination of the Contents of Effective Constituents in Swertia macrosperma C.B. Clark by HPLC / 中国药房

OBJECTIVE:To establish an HPLC method for the determination of the contents of Decussatin,Bellidifodin,Methylswertianin and Swerchirin in Swertia macrosperma C.B.Clark.METHODS:The determination was performed on VP-ODS C18(150 mm? 4.60 mm,5 ? m),with the mobile phase consisting of methanol-water-phosphoric acid(70∶ 30∶ 0.4),the detection wavelength set at 254 nm,the flow rate at 1.0 mL? min-1 and the column temperature at 20℃.RESULTS:The calibration curves of Decussating,Bellidifodin,Methylswertianin and Swerchirin were in good linearity in the range of 0.172～ 0.86 ? g,0.224～ 1.344 ? g,0.144～ 0.72 ? g and 0.154～ 0.77? g,respectively.The average recoveries were 98.18%(RSD=1.19%),99.32%(1.52%),98.44%(1.23%)and 97.68%(1.57%),respectively.CONCLUSION:The method is rapid and precise,with accurate and reliable results.

Antioxidative effect of xanthones in Vitro / 中成药

AIM: To study the antioxidative effect of three kinds of xanthone:methylswertianin(MET), bellidifodin(BEL) and decussatin (DEC) extracted from Swertia macrosperma C.B. clark. METHODS: Hydroxy radical was generated from H_2O_2 and VC-Fe~ 2+ system; MDA contents in liver homogenate and mitochondria were measured by thiobabituric acid assay; the hemolysis of RBC and the swelling extent of mitochondria were detected by spectrophotometric methods. RESULTS: Xanthones could inhibit the generation of MDA, the hemolysis of RBC, and the swelling of mitochondria. The inhibitory effect of BEL was stronger than that of MET and DEC. CONCLUSION: Xanthones possess a good antioxidant activity.