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Objective: To investigate the effects of depside salt from salvia miltiorrhizae (DSSM) in repairing advanced glycation end products (AGE)-induced late endothelial progenitor cell (EPC) dysfunction, and its possible molecular mechanism., Methods: Mononuclear cells (MNCs) were separated using density gradient centrifugation from human umbilical cord blood, and cultured with EGM-2-MV culture fluid to late EPCs. Then the EPCs were divided into 5 groups: Group A incubated with 200 microg/mL AGE-modified bovine serum albumin (AGE-albumin) alone (A), Groups B, C and D with equal dosage of AGE-albumin plus DSSM at different dosages (0.1 microg/mL, 1 microg/mL, and 10 microg/mL), Group E with 200 microg/mL of unmodified-AGE. The late EPCs apoptosis was detected by Annexin V+/PI double-stain, angiogenic capacity was detected by ECMatrix-gel, mRNA expressions of the receptor for AGE (RAGE) and endothelial nitric oxide synthase (eNOS) were measured by reverse-transcriptase polymerase chain reaction (RT-PCR), and the protein expressions of RAGE, eNOS and protein kinase (Akt) were measured by Western blot., Results: Compared with Group E, in Group A, the Annexin V+/PI- ratio and expression of RAGE in EPCs increased, the angiogenic capacity, mRNA and protein expressions of eNOS, and protein expression of Akt decreased significantly. These abnormal changes in Groups C and D were significantly smaller than those in Group A (P < 0.05 or P < 0.01). And all the indices in Group D were adjacent to those in Group E, showing insignificant difference between the two groups (P > 0.05)., Conclusions: AGE could injure the function of EPCs, revealing increase of cell apoptosis and migration, deprivation of angiogenic capacity in vitro. DSSM could repair the EPCs dysfunction induced by AGE-albumin. Up-regulation of eNOS and Akt in these cells may be involved in the mechanism.

Objective: To determine the presence of membrane testosterone receptors in cultured vascular smooth muscle cells (VSMC), and investigate their relationship with classical intracellular androgen receptors (iAR)., Methods: VSMCs were cultured from the thoracic aorta of male Sprague-Dawley rats by the explant method. Subconfluent VSMCs were incubated with serum-free medium for 24 h to obtain quiescent non-dividing cells, and then treated with the indicated agents. The aliquots of VSMCs were labeled with testosterone-BSA-FITC (T-BSA-FITC) and analyzed by flow cytometry. Classical iARs in intact- and permeabilized-cells were detected with anti-iAR antibodies and FITC-labeled secondary antibodies by immunofluorescence, followed by flow cytometry analysis., Results: Incubation of VSMCs with T-BSA-FITC obviously increased their relative fluorescence intensity at 10 sec as compared with the untreated controls (P < 0.01), and so did it at 10 min in comparison with the treatment with BSA-FITC alone or together with free testosterone (P < 0.01). Pretreatment with iAR antagonist flutamide exhibited no significant influence on the relative fluorescence intensity of VSMCs (P = 0.318). Traditional iARs were not detectable on the surface of intact VSMCs, although permeabilized cells contained iARs., Conclusion: VSMCs contain testosterone receptors in the plasma membrane, and these membrane receptors are not identical to classical iARs.

Objective: Clinical studies have shown decreased levels of sexual hormones, particularly testosterone deficiency, in men with chronic heart failure (CHF). The authors aimed to investigate the effect of testosterone on cardiac function and the possible mechanism of androgen protecting the heart in male rats., Methods: Forty-three male SD rats were randomly divided into 3 groups: right heart failure (RHF, n = 15), physiologic testosterone treatment (TT, n = 15) and control (n = 13). The RHF group was given intraperitoneal injection of monocrotaline at 60 mg/kg to make RHF models; the TT group was injected with testosterone at 5 mg/kg 3 days after monocrotaline administration; and the control group received equal volume of saline. The CD34+ cells in the peripheral blood of each rat were counted by flow cytometry. The levels of serum testosterone and tumor necrosis factor alpha (TNF-alpha) were measured by chemiluminescence immunoassay and enzyme linked immunosorbent assay, respectively. The hearts, lungs and livers of all the surviving rats were excised at 6 weeks for pathological and immunohistochemical examinations., Results: The level of serum testosterone was gradually decreased, while that of TNF-alpha obviously increased in the RHF group. After testosterone treatment, the TT group showed a remarkable improvement of cardiac performance and a significant decrease in the level of serum TNF-alpha as compared with the RHF group. Statistically significant differences were observed neither in the CD34+ cell count in the peripheral blood nor in the CD34+ expression of the myocardial cells between the TT and RHF groups., Conclusion: Physiological supplementation of testosterone can improve the cardiac function of RHF male rats, probably through its inhibition of TNF-alpha rather than by autologous mobilization of bone marrow stem cells.

Objective: To explore the acute effects of testosterone at the physiological level on PGF2alpha-induced increase in intracellular Ca2+ in cultured vascular smooth muscle cells (VSMCs)., Methods: VSMCs from the thoracic aorta of male Sprague-Dawley rats were cultured using the explant method. The subconfluent VSMCs were incubated with serum-free medium for 24 hours to obtain quiescent non-dividing cells and then treated with the indicated agents. For the measurement of [Ca2+]i, the VSMCs were loaded with fura-2. Changes of [Ca2+]i were determined ratiometrically with a Nikon TE-2000E system., Results: The resting level of [Ca2+]i was around 100 nmol/L in the VSMCs. Exposing cells to perfusate containing 10 micromol/L PGF2alpha triggered an immediate and transient peak in [Ca2+]i, which gradually decreased afterwards. Interference at the peak with the physiological concentration (40 nmol/L) of testosterone significantly decreased the peak-to-baseline time of [Ca2+]i, compared with ethanol vehicle (104.9 +/- 27.0 s vs 153.5 +/- 40.4 s, P < 0.01). Pretreatment with testosterone at 40 nmol/L for 2 minutes also reduced the peak-to-baseline time of [Ca2+]i significantly in comparison with the ethanol control (120.6 +/- 32.0 s vs 151.4 +/- 27.4 s, P < 0.01), but it had no significant effect on the peak level of PGF2alpha-induced intracellular Ca2+ (390.0 +/- 126.0 nmol/L vs 403.4 +/- 160.7 nmol/L, P > 0.05)., Conclusion: Testosterone at physiological concentration inhibits PGF2alpha-induced Ca2+ fluxes, probably via receptor-operated calcium channels by a non-genomic mechanism in VSMCs, which may be involved in the vasodilatory effect of testosterone.

Objective: To compare coronary lesion characteristics by coronary angiography (CAG) between yellows and whites., Methods: CAG results of 3021 Chinese patients, defined as yellows, from Nanjing and 3230 Australian patients, defined as whites, from Sydney were analyzed. The coronary artery lesion was evaluated by the number and location of coronary lesion and Gensini scores., Results: (1) Coronary stenosis was diagnosed in 69.4% Chinese patients and 75.5% in Australians. The involved coronary arteries were left anterior descending branch, right coronary artery, left circumflex branch and left main coronary artery in a descending order in both Chinese and Australians. (2) The incidences of three-vessel disease and left main disease of yellows were significantly lower than that of whites in both male (29.8% vs. 34.0% and 9.6% vs. 14.2%) and female patients (15.8% vs. 26.2% and 4.9% vs. 11.6%) respectively, all P < 0.05. (3) There was an age-dependent Gensini scores increase in both yellows and whites patients and Gensini scores at age 40 and more of whites were significantly higher than those of yellows in comparable age groups., Conclusion: The incidences of three-vessel disease and left main disease as well as Gensini score were significantly higher in Australian patients than those of Chinese patients.

Objective: To investigate the effect of hemorrhagic shock without resuscitation on expression of Toll-like receptor (TLR) in myocardium of rats and its significance., Methods: Forty-five C57BL/6 mice were randomly divided into 3 groups: hemorrhagic group, sham operation group and lipopolysaccharide (LPS) group, with 15 mice in each group. The hemorrhagic shock mouse model was reproduced by heart puncture. Expression levels of TLR2 mRNA and TLR4 mRNA were determined by reverse transcription-polymerase chain reaction (RT-PCR). Left ventricular end-systolic pressure (LVESP) was determined and adopted as an index of left ventricle contractile function., Results: (1)Both hemorrhagic shock and LPS challenge led to a reduction in arterial blood pressure in mice when compared with sham operation group. Both hemorrhagic shock and LPS challenge could result in left ventricle contractile dysfunction when compared with sham operation group. (2)Expression levels for TLR2 and TLR4 genes were upregulated in myocardium to various extents after hemorrhagic shock and LPS challenge, while in contrast the changes were absent in sham operation group., Conclusion: (1)The up-regulation of TLR2 and TLR4 genes is closely related with hemorrhagic shock and LPS-induced left ventricle contractile dysfunction, and there may exist a difference in signal transduction pathway between the two pathological conditions. (2)The host ability of innate immune response may be reinforced by the up-regulation of TLR2 and TLR4, whereas overexpression of them may also impair the function of tissues or organs.

Objective: To investigate the efficacy of adaptive pressure support servo-ventilation (APSSV) on Cheyne-Stokes respiration (CSR) in congestive heart failure (CHF)., Methods: 14 patients with CHF and CSR were recruited. During sleep, oxygen therapy and APSSV were separately performed. Comparison before and after each treatment was made for the following items: a) parameters of sleep respiration, sleep structure and quality; b) cardiac function index such as left ventricle ejection fraction (LVEF) and 6 minutes' walking distance; c) plasma endothelin-1 (ET-1) levels., Results: Compared with the baseline level before treatment, the apnea hypopnea index significantly decreased during oxygen therapy (P < 0.05) and further declined during APSSV (P < 0.01); on the contrary, the lowest pulse oxygen saturation increased during oxygen therapy (P < 0.05) and further elevated during APSSV (P < 0.01). Compared with arousal index before treatment, it was significantly lower during oxygen therapy (P < 0.05) and the lowest during APSSV (P < 0.01). Compared with both during oxygen therapy and before treatment, during APSSV the percentage ofI + II stage sleep time/total sleep time was significantly lower while the percentage of III + IV stage sleep time/total sleep time was significantly higher. The above percentages during oxygen therapy and before treatment showed no significant difference (P < 0.05). LVEF was significantly higher during APSSV than during oxygen therapy and before treatment (P < 0.05). Six minutes' walking distance was the shortest before treatment and the longest during APSSV. There was a significant difference among that before treatment, during oxygen therapy and APSSV (all P < 0.01). The plasma ET-1 level showed significantly lower during APSSV than that before and during oxygen treatment (P < 0.05), but no significant difference between the levels before and during oxygen treatment (P > 0.05)., Conclusion: APSSV, more effective than oxygen therapy, is of great clinical significance in improvement of CHF and its prognosis by a better sleep and breathing.

Objective: To investigate the effects of testosterone exposure on androgen receptor (AR) mRNA expression in cultured vascular smooth muscle cells (VSMCs)., Methods: VSMCs were cultured from the thoracic aorta of male SD rats using explant method. The total RNA was extracted by one-step guanidine isothiocyanate method and subjected to Northern blotting analysis for determining AR mRNA level. The effect of testosterone on the viability and growth of VSMCs were studied by means of cell counting and tritiated thymidine incorporation assay., Results: Testosterone treatment of the synchronized VSMCs for 24 h increased intracellular AR mRNA expression in a dose-dependent manner, with relative mRNA level of 97.67+/-7.22, 98.00+/-13.58, 143.33+/-10.99, 177.67+/-14.62 and 185.67+/-19.97 corresponding to testosterone doses of 0, 4 nmol/L, 40 nmol/L, 400 nmol/L and 4 micromol/L, respectively. Incubation of synchronized VSMCs with testosterone at a physiological level of 40 nmol/L for 24 h resulted in a mean of 30% up-regulation of AR mRNA level, compared with that of untreated cells. During AR up-regulation, testosterone had no significant effects on the cell number and DNA synthesis of VSMCs as measured by cell counting and tritiated thymidine incorporation assay., Conclusion: Self-initiated up-regulation of AR mRNA expression occurs in synchronized VSMCs, which is independent of testosterone that influences apoptosis or growth rate of the cells, suggesting the involvement of AR in androgen regulational at the transcription level in VSMCs.