Combined antihypertensive effect of GSY and metoprolol,based on endothelium-dependent vasodilatation function

OBJECTIVE To investigate the synergistic effect on dilating blood vessels and anti-hypertension of GYS combined with metoprolol.METHODS ① Spontaneously hypertensive rats(SHR)were administered orally with the vehicle,GSY,metoprolol or GSY combined with metoprolol for 4weeks.Blood pressure,which included SBP,DBP and MBP was measured by a noninvasive method every week.At the end of4 weeks,blood was drawn from the ophthalmic venous plexus to determine blood fat levels(serum TC,TG,LDL-c,HDL-c),liver function(serum ALT,AST),and kidney function(serum BUN,UA and Cr)by the ACCUTE(TBA-40FR)automatic.② The aortae of normal SD rats were prepared and cleaned from periadventitial fat and surrounding connective tissue and cut transversely into 4-mm width rings.To observe different concentration of GYS,metoprolol or GSY combined with metoprolol causing relaxation of the isolated aortic rings precontracted until a stable plateau by noradrenaline(NA)directly or in the presence of eNOS inhibitor L-NAME and cyclooxygenase inhibitor indomethacin(INDO)respectively.③ The concentrations of plasma GSY was determined by the HPLC after rats administered orally with GSY or GSY combined with metoprolol for single-dose.DAS data processing software calculated the pharmacokinetic parameters of GSY.RESULTS There was a significant synergism between GYS and metoprolol in lowering blood pressure and the concentrations of serum TC and LDL-c of SHR.The relaxant effect of GYS combined with metoprolol on the aortic rings precontracted by NA could be attenuated by L-NAME or INDO.The AUC0-tof GSY significantly increased after in conjunction with metoprolol.CONCLUSION GYS combined with metoprolol increases the concentrations of plasma GSY and synergistically lowers blood pressure based on endothelium-dependent vasodilatation function(EDVF).

The effect of aerobic training on endothelium-dependent vasodilatation in patients with coronary artery disease who were revascularized and young men

Aim: The aim of this study was to determine the effect of training on endothelium-dependent vasodilatation in patients with coronary artery disease (CAD) after revascularization and healthy young men. Background: Impaired endothelial function has been observed in patients with CAD and those with CAD risk factors. Studies have shown that exercise can enhance endothelial function. Methods: This experimental cross-sectional study was conducted on patients with CAD (3 months after CABG and PCI) and students of medical school in 2011. Endothelium dependent dilation of the brachial artery was determined by using high-resolution vascular ultrasonography through flow-mediated vasodilatation (FMD) after induction of ischemia, and the data were analyzed using SPSS, dependent t-test and ANCOVA. Findings: The findings showed that at baseline, FMD was reduced in revascularized patients, when compared with healthy young men, after 8 weeks, and exercise training significantly improved FMD in patients underwent training group [from 4.31 ± 1.45 (SD)% to 6.15 ± 0.773 (SD)%, p p ed unchanged, and even after aerobic training, it did not significantly modify the brachial artery diameter in these groups. Conclusion: Our study demonstrates that endothelial dysfunction persisting in CAD patients after revascularization and aerobic training can improve endothelial function in different vascular beds in CAD patients and healthy young men. This may contribute to the benefit of regular exercise in preventing and restricting cardiovascular disease.

Scutellarin attenuates endothelium-dependent aasodilation impairment induced by hypoxia reoxygenation, through regulating the PKG signaling pathway in rat coronary artery

Scutellarin(SCU), a flavonoid from a traditional Chinese medicinal plant. Our previous study has demonstrated that SCU relaxes mouse aortic arteries mainly in an endothelium-depend-ent manner. In the present study, we investigated the vasoprotective effects of SCU against HR-induced endothelial dysfunction(ED) in isolated rat CA and the possible mechanisms involving cyclic guanosine monophosphate(c GMP) dependent protein kinase(PKG). The isolated endothelium-intact and endothelium-denuded rat CA rings were treated with HR injury. Evaluation of endothelium-dependent and-independent vasodilation relaxation of the CA rings were performed using wire myography and the protein expressions were assayed by Western blotting. SCU(10–1 000 μmol·L-1) could relax the endothelium-intact CA rings but not endothelium-denuded ones. In the intact CA rings, the PKG inhibitor, Rp-8-Br-c GMPS(PKGI-rp, 4 μmol·L-1), significantly blocked SCU(10–1 000 μmol·L-1)-induced relaxation. The NO synthase(NOS) inhibitor, NO-nitro-L-arginine methylester(L-NAME, 100 μmol·L-1), did not significantly change the effects of SCU(10–1 000 μmol·L-1). HR treatment significantly impaired ACh-induced relaxation, which was reversed by pre-incubation with SCU(500 μmol·L-1), while HR treatment did not altered NTG-induced vasodilation. PKGI-rp(4 μmol·L-1) blocked the protective effects of SCU in HR-treated CA rings. Additionally, HR treatment reduced phosphorylated vasodilator-stimulated phosphoprotein(p-VASP,phosphorylated product of PKG), which was reversed by SCU pre-incubation, suggesting that SCU activated PKG phosphorylation against HR injury. SCU induces CA vasodilation in an endothelium-dependent manner to and repairs HR-induced impairment via activation of PKG signaling pathway.

TRPC5 is essential in endothelium-dependent contraction of aorta from diet-induced obese mice

The role of the Ca^(2+)-permeable ion channel TRPC5 in regulating vasocontraction in obesity is poorly understood.Here,we investigated whether TRPC5 contributes to vascular dysfunction in obesity by promoting endothelium-dependent contraction via activation of cytosolic phospholipase A2(cPLA_(2))in the aortic endothelial cells of obese mice.Acetylcholine-induced endothelium-dependent relaxation and contraction in the aorta were measured us-ing wire myography.PLA_(2)activity was measured by the fluorogenic PLA_(2)substrate Bis-BODIPY^(TM)FL C_(11)-PC.The intracellular Ca^(2+)level in response to acetylcholine was measured by Fluo-4 fluorescence.Endothelium-derived contracting factors were assessed by enzyme immunoassay.Diet-induced obesity(DIO)attenuated endothelium-dependent vasodilation,enhanced endothelium-dependent contraction(EDC),and increased the expression of TRPC5 in the mouse aorta.Activation of TRPC5 promoted EDC in the wild-type mouse aorta,whereas pharma-cological inhibition and genetic knockout of TRPC5 decreased EDC in the DIO mouse aorta.Moreover,cPLA_(2)phosphorylation and activity were higher in aortic endothelial cells from DIO mice,and this was attenuated by inhibition and knockout of TRPC5.Cyclooxygenase 2(COX-2)expression was increased in DIO mouse endothe-lium and was decreased by a TRPC5 inhibitor and knockout of TRPC5.Release of prostaglandins F_(2α(PGF_(2α)and E 2(PGE 2)was involved in TRPC5-regulated EDC in DIO mice.This study demonstrated that TRPC5 contributes to endothelial and vascular dysfunction and is involved in EDC through activation of cPLA_(2)and enhanced COX-2-PGF_(2α)/PGE_(2)levels in DIO mice.

Sustained Contraction of Isolated Rabbit Thoracic Aortic Rings in Endothelial-dependent Manner Induced by βγ-CAT

In vertebrates, non-lens βγ-crystallins are widely expressed in various tissues and their functions are not well known. The molecular mechanisms of trefoil factors （TFFs）, which involved in mucosal healing and tumorigenesis, have remained elusive. βγ-CAT is a novel multifunctional protein complex of non-lens βγ-crystallin and trefoil factor from frog skin secretions. Here we report that βγ-CAT could induce sustained contraction of isolated rabbit aortic rings in dosage （2-35nmol/L） and endothelium dependent manners （P〈0.01 ）. In addition, in situ immunofluorescence indicated that positive TNF-α signals were mainly detected at the endothelial cell layer of βγ-CAT （25nmol/L） treated rings. Furthermore, βγ-CAT induced primary cultured rabbit thoracic aortic endothelial cells （RAECs） rapidly to release TNF-α. After βγ-CAT （25nmol/L） treated for 10 and 30min, the levels of the endothelial cells released TNF-ct were 34.17±5.10 pg/mL and 98.01±4.67 pg/mL （P〈0.01）, respectively. In conclusion, βγ-CAT could induce sustained contraction of isolated aortic rings, and the contractile effect might be partially explained by the release of TNF-α. These findings will give new insight into understanding the functions and physiological roles of non-lens βγ-crystallins and trefoil factors.

Reduced expression of SK3 and IK1 channel proteins in the cavernous tissue of diabetic rats

The small （SK3） and intermediate （IK 1） conductance calcium-activated potassium channels could have key roles in the endothelium-dependent hyperpolarization factor pathway, which is believed to contribute to normal penile erection function. We aimed to investigate the expression of SK3 and IK1 in diabetic rodents. The experimental diabetes model was induced in 8-week-old male Sprague-Dawley rats （250-300 g） by a single administration of streptozotocin. Both the diabetes mellitus group （DM group, n = 20） and the control group （NDM group, n = 10） were injected with a low dose of apomorphine to allow for the measurement and comparison of the corresponding penile erections. The mRNA and protein expression levels of SK3 and IK1 were measured by reverse transcription polymerase chain reaction and western blot, respectively. Erectile function was significantly decreased in the DM group compared with control group （P 〈 0.05）. The mRNA and protein expression levels of SK3 and IK1 were reduced in the cavernous tissue of diabetic rats compared with the control group （P 〈 0.05）. Diabetes inhibits mRNA and protein expression of both SK3 and IK1 in the cavernous tissue of diabetic rats. This could play a key role in the development of erectile dysfunction in diabetic rats.

Antihypertensive efficacy of extract of Hedera helix in high salt-induced hypertensive Sprague-Dawley rats

Objective: To explore the antihypertensive effect of extracts from the leaves of Hedera helix(H. helix) on normotensive and hypertensive rats in-vivo followed by vasodilatory studies in-vitro.Methods: The crude methanolic extract was prepared and the activity directed fractionation was carried out. Spectrophotometric analysis of total phenolic and flavonoid content was also done. HPLC analysis was performed for the detection of hederacoside C. In-vivo blood pressure study was carried out in normotensive and high salt-induced hypertensive SpragueDawley rats. Isolated aortic tissues from rat and rabbit were used for in-vitro studies. The effects were recorded and analyzed through PowerL ab data acquisition system. Results: Crude extract of H. helix(1-30 mg/kg) decreased blood pressure to greater extent in high salt-induced hypertensive rats in-vivo compared to the normotensive [Max. fall(58.59±0.02) mm Hg vs.(67.53±3.07) mmH g]. The n-hexane, chloroform, ethyl acetate and aqueous fractions were also checked. These fractions were more effective in hypertensive rats. Aqueous fraction was more potent and n-hexane the least. In isolated rat aortic rings precontracted with phenylephrine, crude extract induced endothelium-dependent effect. The endothelium-dependent component of vasodilatory effect was ablated with L-NAME, and denudation of endothelium. The aqueous fraction was most potent vasodilator. In aortic rings from hypertensive rats, extract and fractions produced partial endothelium-independent effect which was not affected by pretreatment with L-NAME, indicating endothelium dysfunction in the hypertensive rats and suggesting additional vasodilatory mechanisms. In rabbit aorta, the extract and fractions also inhibited phenylephrine and high K^+-induced precontractions, and shifted Ca^(++) concentration–response curves. Conclusions: Our findings indicate that extract and fractions of H. helix are antihypertensive remedies, which is the outcome of vasodilatory effect. This vasodilatory effect is mediated through nitric oxide and Ca^(++) antagonism.

Absorbed Bioactive Compounds Replicate GuanxinⅡ-Induced Endothelium-Associated in/ex vivo Vasodilation

Objective:To develop an interference-free and rapid method to elucidate GuanxinⅡ(GXⅡ)'s representative vasodilator absorbed bioactive compounds(ABCs)among enormous phytochemicals.Methods:The contents of ferulic acid,tanshinol,and hydroxysafflor yellow A(FTA)in GXⅡ/rat serum after the oral administration of GXⅡ(30 g/kg)were detected using ultra-performance liquid chromatography-mass spectrometry.Totally 18 rats were randomly assigned to the control group(0.9%normal saline),GXⅡ(30 g/kg)and FTA(5,28 and 77 mg/kg)by random number table method.Diastolic coronary flow velocity-time integral(VTI),i.e.,coronary flow or coronary flow-mediated dilation(CFMD),and endothelium-intact vascular tension of isolated aortic rings were measured.After 12 h of exposure to blank medium or 0.5 mmol/L H_(2)O_(2),endothelial cells(ECs)were treated with post-dose GXⅡof supernatant from deproteinized serum(PGSDS,300μL PGSDS per 1 m L of culture medium)or FTA(237,1539,and 1510 mg/m L)for 10 min as control,H_(2)O_(2),PGSDS and FTA groups.Nitric oxide(NO),vascular endothelial growth factor(VEGF),endothelin-1(ET-1),superoxide dismutase(SOD),malondialdehyde(MDA)and phosphorylated phosphoinositide 3 kinase(p-PI3K),phosphorylated protein kinase B(p-AKT),phosphorylated endothelial nitric oxide synthase(p-e NOS)were analyzed.PGSDS was developed as a GXⅡproxy of ex vivo herbal crude extracts.Results:PGSDS effectively eliminates false responses caused by crude GXⅡpreparations.When doses equaled the contents in GXⅡ/its post-dose serum,FTA accounted for 98.17%of GXⅡ-added CFMD and 92.99%of PGSDS-reduced vascular tension.In ECs,FTA/PGSDS was found to have significant antioxidant(lower MDA and higher SOD,P<0.01)and endothelial function-protective(lower VEGF,ET-1,P<0.01)effects.The increases in aortic relaxation,endothelial NO levels and phosphorylated PI3K/Akt/e NOS protein induced by FTA/PGSDS were markedly abolished by NG-nitro-L-arginine methyl ester(L-NA,e NOS inhibitor)and wortmannin(PI3K/AKT inhibitor),respectively,indicating an endothelium-dependent vasodilation via the PI3K/AKT-e NOS pathway(P<0.01).Conclusion:This study provides a strategy for rapidly and precisely elucidating GXⅡ's representative in/ex vivo cardioprotective absorbed bioactive compounds(ABCs)-FTA,suggesting its potential in advancing precision ethnomedicine.

Association between glioblastoma cell-derived vessels and poor prognosis of the patients

Background:Vessels with different microcirculation patterns are required for glioblastoma(GBM)growth.However,details of the microcirculation patterns in GBM remain unclear.Here,we examined the microcirculation patterns of GBM and analyzed their roles in patient prognosis together with two well-known GMB prognosis factors(O^(6)-methylguanine DNA methyltransferase[MGMT]promoter methylation status and isocitrate dehydrogenase[IDH]mutations).Methods:Eighty GBM clinical specimens were collected from patients diagnosed between January 2000 and December 2012.The microcirculation patterns,including endothelium-dependent vessels(EDVs),extracellular matrix-dependent vessels(ECMDVs),GBM cell-derived vessels(GDVs),and mosaic vessels(MVs),were evaluated by immunohistochemistry(IHC)and immunofluorescence(IF)staining in both GBM clinical specimens and xenograft tissues.Vascular density assessments and three-dimensional reconstruction were performed.MGMT promoter methylation status was determined by methylation-specific PCR,and IDH1/2 mutations were detected by Sanger sequencing.The relationship between the microcirculation patterns and patient prognosis was analyzed by Kaplan-Meier method.Results:All 4 microcirculation patterns were observed in both GBM clinical specimens and xenograft tissues.EDVs were detected in all tissue samples,while the other three patterns were observed in a small number of tissue samples(ECMDVs in 27.5%,GDVs in 43.8%,and MVs in 52.5%tissue samples).GDV-positive patients had a median survival of 9.56 months versus 13.60 months for GDV-negative patients(P=0.015).In MGMT promoter-methylated cohort,GDV-positive patients had a median survival of 6.76 months versus 14.23 months for GDV-negative patients(P=0.022).Conclusion:GDVs might be a negative predictor for the survival of GBM patients,even in those with MGMT promoter methylation.

Organ bath in detecting the effect of one-hour warm ischemia on pulmonic arteries and bronchi from non-heart-beating donor lungs

Background Non-heart-beating donor lung has been a promising source of lung transplantation. Many studies on non-heart-beating donor lungs are based on animal lung transplantation. In this study, we assessed by organ bath the effect of one-hour warm ischemia on the non-heart-beating donor lung in terms of the integrity of contractile and relaxant functions and tissue structures of pulmonic arteries and bronchi. Methods Sixteen Swedish pigs were randomly classified into two groups： heart-beating donor group and 1-hour warm ischemia non-heart-beating donor group. Pulmonic and bronchial rings were taken from the isolated left lungs of the pigs. The pulmonic rings were stimulated by U-46619 （5.7 mol/L） and acetylcholine （104 mmol/L） to assess the contractile abilities of smooth muscle and the endothelium-dependent relaxation response, respectively. As such, acetylcholine （10^-5 mmol/L） and natrium arachidonic acid （0.01%） were used to detect the contraction of bronchial smooth muscle and epithelium-dependent relaxation response. Meanwhile, the variances of precontraction tension of control groups were recorded to measure whether there was spontaneous relaxation during endothelium/epithelium-dependent relaxation course. Finally, papaverine solution （10.4 mmol/L） was used to detect the non-endothelium/epithelium-dependent relaxant abilities of pulmonic and bronchial smooth muscles. Results There was no significant difference in the tension values of precontraction of pulmonic rings （P 〉0.05）, endothelium-dependent relaxation （P 〉0.05）, precontraction of bronchial rings （P 〉0.05） and epithelium-dependent relaxation （P 〉0.05） between the heart-beating donor group and the 1-hour warm ischemia non-heart-beating donor group. And the pulmonic and bronchial rings of each subgroup B had no spontaneous relaxation. Finally, papaverine solution relaxed the smooth muscle of all the rings completely. Conclusions The results of this experiment suggest that the contractile and relaxant functions and tissue structures of pulmonic arteries and bronchi are not damaged after warm ischemia for 1 hour, and support the further study of non-heart-beating donor lung.