Objective To explore the effect of endogenous sulfur dioxide (SO2)on the apoptosis induced by cobalt chloride (CoCl2)in the human pulmonary arterial endothelial cells (HPAECs).Methods CoCl2was used in the primary HPAECs to mimize hypoxia-induced cell apoptosis.The aspartate aminotransferase 1(AAT1),and the key enzyme generating endogenous SO2 were over -expressed by transfecting HPAECs with lentivirus containing AAT1 cDNA.HPAECs were divided into 4 groups:vehicle group,vehicle + CoCl2 group,AAT1 group and AAT1 + CoCl2 group.The expressions of AAT1,B-cell lymphoma-2 (bcl-2),bcl-associated X protein (bax),Caspase-3 and activated Caspase-3 (cleaved Caspase-3)in the HPAECs were measured by Western blot.The AAT activity was assessed with colorimetry method.The SO2 content in the HPAECs was in situ observed by SO2-specific fluorescent probe.The HPAECs apoptosis was investigated by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL)assay.Results There were significant differences in the endogenous SO2 content,the expre-ssions of AAT1 and bcl-2,and the ratio of cleaved Caspase-3/Caspase-3 among 4 groups of HPAECs were (F＝147.364,23.738,6.521,64.884,all P＜0.05).However,there was no difference in the expression of bax among 4 groups of HPAECs (F＝1.620,P＞0.05).Compared with vehicle group,AAT activity [(0.96 ± 0.24)Carmen's unit/μg vs.(2.21 ± 0. 60)Carmen's unit/μg],endogenous SO2 content (40.71 ± 7.72 vs.105.60 ± 16.20)and bcl-2 expression (0.59 ± 0.19 vs.1.02 ± 0.20)in the HPAECs of vehicle +CoCl2 group were significantly de-creased,while the cell apoptosis assessed by TUNEL and the ratio of cleaved Caspase-3/Caspase-3 (1.56 ± 0.25 vs.0.95 ± 0.13)were significantly increased (all P＜0.05).However,there were no differences in the expression of AAT1 (0. 50 ± 0.12 vs.0.53 ± 0.11)in the HPAECs between vehicle group and vehicle+CoCl2 group (P＞0.05). The SO2 content (351.50 ± 42.43 vs.105.60 ± 16.20)and AAT1 expression (1.22 ± 0.33 vs.0.53 ± 0.11)in the HPAECs of AAT1 group were higher than those of vehicle group (all P ＜0. 05 ). Compared with AAT1 group, endogenous SO2content (333.50 ± 46.22 vs.351.50 ± 42.43)and the expression of AAT1 (1.26 ± 0.36 vs.1.22 ± 0.33)and bcl-2 (1.14 ± 0.38 vs.1.03 ± 0.27)in the HPAECs of AAT1 +CoCl2group did not change (all P＞0. 05).Moreover,no difference was observed in the HPAECs apoptosis assessed by TUNEL and the ratio of cleaved Caspase-3/Caspase-3 (0.51 ± 0.17 vs.0.50 ± 0.11)between the two AAT1 -overexpressed groups (all P ＞0. 05).Conclusion Endo-genous SO2inhibited the hypoxic HPAECs apoptosis stimulated by the treatment of CoCl2.

Objective To explore the effect of different concentrations of endothelin-1 (ET-1)on the en-dogenous nitric oxide (NO)and hydrogen sulfide (H2S)pathways of vascular smooth muscle cells (A7r5 cell lines)in rats.Methods A7r5 cell lines were divided into the control group and the experimental group.ET-1 at a concentra-tion of 10 -8-10 -6 mol/L was added into the experimental group,and as for the control group,the same volume of sterile phosphate buffered saline (PBS)buffer solution was added.The content of NO and H2S in A7r5 cell lines was detected by fluorescent NO probe and H2S probe after ET-1 stimulation for 48 h,respectively.The content of NO in the supernatant was measured by NO assay kit at 48 h of the incubation.The content of H2S in the supernatant was measured by polarographic H2S sensor at 48 h of the incubation. The expressions of inducible nitric oxide synthase (NOS2),endothelial nitric oxide synthase (NOS3),cystathionine -γ -lyase (CSE),cystathionine -β -synthase (CBS)and proliferating cell nuclear antigen (PCNA)were detected by the Western blot method.Results The rela-tive fluorescence intensity of the content of NO in the A7r5 cell lines of ET-1 10 -8,10 -7 and 10 -6mol/L groups (0. 078 ± 0. 080,0.075 ± 0.002,0.056 ± 0.009)was markedly lower than that in the control group(0.094 ± 0. 061), and the differences were statistically significant(F＝15.248,P＜0.05);Compared with the control group[(2. 131 ± 0. 484)μmol/L],the content of NO in the supernatant of the experimental groups [(1.391 ± 0.134 )μmol/L, (1.219 ± 0. 280)μmol/L,(1.116 ± 0.181)μmol/L]was significantly decreased,and the differences were statistically significant(F＝20.833,P＜0.01);NOS2 protein expression(0.457 ± 0.097,0.462 ± 0.116,0.438 ± 0.180)was decreased markedly compared with that of the control group(0.721 ± 0.222),and the differences were statistically sig-nificant(F＝6.196,P＜0.01),but the expression of NOS3 showed no significant differences(F＝2.669,P＞0.05). The relative fluorescence intensity of the content of H2S in the A7r5 cell lines of ET-1 10 -8,10 -7 and 10 -6mol/L groups (0.063 ± 0.002,0.056 ± 0.008,0.042 ± 0.009)was markedly lower than that in the control group (0.082 ± 0. 006),and the differences were statistically significant(F ＝16.297,P＜0.01);Compared with the control group [(29.439 ±4.236)μmol/L],the content of H2S in the supernatant of the experimental groups [(17.516 ±5.144) μmol/L,(14.481 ± 4.885)μmol/L]was significantly decreased,and the differences were statistically significant (F＝12.518,P ＜0.01).CBS protein expression(0.359 ± 0.096,0.270 ± 0.038,0.174 ± 0.051)was decreased markedly compared with that of the control group(0.707 ± 0.107),and the differences were statistically significant (F＝20.833,P＜0.01),and the expression of CSE showed no significant differences(F＝0.708,P＞0.05).The data showed that PCNA protein expression in the 10 -7mol/L ET-1 group(0.686 ± 0.180)significantly increased com-pared with that of the control group(0.437 ± 0.191),and the difference was statistically significant (t＝ -2.840,P＜0.01).Conclusion ET-1 stimulation can lead to the proliferation of vascular smooth muscle cells and down-regu-late its endogenous NO and H2S pathways.

Objective To investigate the effects of endogenous sulfur dioxide (SO2) on the oxidative stress induced by cobalt chloride (CoCl2) in the rat pulmonary artery smooth muscle cells (PASMCs).Methods Rat PASMCs were treated with 200 μ mol/L CoCl2 to mimic the hypoxia insult.Endogenous SO2 generating enzyme aspartate aminotransferase 1 (AAT1) expression was upregulated or downregulated (AAT1 sh) by transfection with lentivirus.Rat PASMCs were randomly divided into 8 groups:vehicle group,vehicle + CoCl2 group,AAT1 group,AAT1 + CoCl2 group,scramble group,scramble + SO2 group,AAT1 sh group and AAT1 sh + SO2 group.SO2 donor Na2 SO3/NaHSO3 at concentration of 100 μ mol/L were added in scramble + SO2 group and AAT1sh + SO2 group.The expressions of AAT1,superoxide dismutase 1 (SOD1) and SOD2 in PASMCs were detected by Western blot method.In situ SO2 content in PASMCs was detected by fluorescent probe.The superoxide anions in PASMCs were labeled by dihydroethidium (DHE) probe under fluorescent microscope.Results Compared with the vehicle group,the levels of SO2 and the expressions of AAT1 (0.221 ± 0.002 vs.0.446 ± 0.004),SOD1 (0.076 ± 0.028 vs.0.171 ± 0.019) and SOD2 (0.080 ± 0.031 vs.0.196 ± 0.018) significantly decreased (all P ＜ 0.01),and superoxide anion increased in rat PASMCs of vehicle + CoCl2 group.Meanwhile,compared with vehicle + CoCl2 group,the levels of SO2 and the expressions of AAT1 (0.839 ± 0.056 vs.0.221 ± 0.002),SOD1 (0.177 ± 0.020 vs.0.076 ± 0.028) and SOD2 (0.195 ±0.018 vs.0.080-± 0.031) markedly increased (all P ＜ 0.01),and superoxide anion decreased in rat PASMCs of AAT1 + CoCl2 group.On the contrary,compared with the scramble group,the levels of SO2 and the expressions of AAT1 (0.062 ±0.017 vs.0.354 ±0.034),SOD1 (0.054 ±0.029 vs.0.157 ±0.023) and SOD2(0.180 ±0.100 vs.0.586 ± 0.176)significantly decreased (all P ＜ 0.01),and superoxide anion increased in rat PASMCs of AAT1sh group.Furthermore,compared with the AAT1 sh group,the levels of SO2 and the expressions of SOD1 (0.155 ± 0.022vs.0.054 ± 0.029) and SOD2 (0.578 ± 0.200 vs.0.180 ± 0.100) significantly increased (all P ＜ 0.01),and superoxide anion decreased in rats PASMCs of AAT1sh + SO2 group.Conclusion Endogenous SO2/AAT1 inhibits CoCl2-induced oxidative stress in rat PASMCs.

OBJECTIVETo explore possible mechanisms of postural tachycardia syndrome (POTS) by comparing plasma intermedin (IMD) during head-up tilt test (HUTT) in children with POTS.

METHODThe study subjects were divided into two groups: POTS group and control group. The POTS group consisted of twenty-nine children (male 14, female 15) with POTS, the mean age (12.4 ±3.1) years old, admitted into Peking University First Hospital from November 2013 to June 2014. The control group consisted of 32 healthy children (male 17, female 15). Their mean age was (11.6±2.2) years old, who were confirmed as healthy by physical examination and HUTT. Finapres Medical System was used to continuously monitor heart rate and blood pressure during HUTT, and electrocadiogram was performed. Supine systolic and diastolic blood pressure, mean arterial pressure (MAP), ΔMAP (standing mean arterial pressure-supine MAP), supine heart rate and ΔHR (standing HR-supine HR) were compared between POTS group and control group. Sandwich immunoluminescence assay was used to test plasma IMD. The plasma IMD level was compared in supine between POTS and control group. The plasma IMD level in supine was compared with HUTT in POTS group.

RESULTNo significant differences were found in age, height, weight, supine systolic and diastolic blood pressure, MAP, ΔMAP and supine heart rate between POTS group and control group (P>0.05). ΔHR in POTS group was significantly higher than that of control group ((48±10) vs. (22±7) beats /min, t=9.797, P<0.05). The plasma IMD level in POTS group was lower than that of control group in supine position ((497±61)×10(-6) vs. (529±58)×10(-6) mg/L, t=2.117, P<0.05). But, it was higher during HUTT than supine IMD in POTS group ((537±57) ×10(-6) vs. (497±61)×10(-6) mg/L, t=-2.464, P<0.05). The plasma delta IMD level (HUTT vs. supine) was positively correlated with delta HR in POTS group (r=0.435, P<0.05).

CONCLUSIONThe excessively high heart rate during HUTT have a positive correlation with plasma IMD, which may play a role in the pathogenesis of POTS in children.

OBJECTIVETo predict the therapeutic efficacy of oral rehydration salts (ORS) by quantifying changes in heart rate during the head-up test (HUT) in children with postural tachycardia syndrome (POTS).

METHODFifty-four children from Peking University First Hospital during July 2005 to September 2013 were enrolled into POTS group. Twenty healthy children were enrolled in this study as the control group. Children with POTS were treated with ORS and successfully followed up. HUT test was done before and at the end of the treatment. POTS children were further divided into responding group and the non-responding group depending on if the symptom scores were reduced by 50% or greater after the treatment. The heart rate, systolic blood pressure (SBP) and diastolic blood pressure (DBP) changes during the HUT test were analyzed between the control group and the POTS patients. A receiver operating characteristic (ROC) curve was used to analyze the predictive value of the increase in heart rates (from the supine to upright) and the maximum upright heart rate in 10 minutes after ORS treatment.

RESULTPOTS children were 6-17 (11.3 ± 3.0) years old and the control group children were 10-12 (11.0 ± 0.8) years old. The changes of the heart rate during the HUT was different between the POTS patients and the controls ((41 ± 10) vs. (20 ± 7) beats/min, t = -10.441, P = 0.000) . There was no significant difference between the two groups in the maximum upright heart rate in 10 minutes during the HUT ( (117 ± 12) vs. (114 ± 8) beats/min, t = -1.322, P = 0.192) . The symptom scores were reduced compared with those before treatment ((3.2 ± 1.8) vs. (5.7 ± 2.0), t = 10.958, P < 0.001) and the heart rate changes from supine to upright were decreased in 30 patients ((33 ± 11) vs. (41 ± 11) beats/min, t = 2.956, P = 0.006). Compared with the non-responding group (28 cases), the heart rate change during the HUT test was great in the responding group (26 cases) before treatment ((46 ± 10) vs. (37 ± 9) beats/min, t = -3.582, P = 0.001), and the maximum upright heart rate in 10 minutes was also high in the responding group ( (122 ± 12) vs. (113 ± 10) beats/min, t = -2.693, P = 0.010). The ROC curve showed that ORS for children with POTS would be predicted to be effective when the pre-treatment increase of heart rate was 41 beats/min (sensitivity 72% and specificity 70%), or when the maximum upright heart rate in 10 minutes was 123 beats/min before treatment (sensitivity 48% specificity 56%). When the two indices were used together, sensitivity was 84% and specificity was 56%.

CONCLUSIONThe changes in heart rate during the HUT was useful in predicting the response to ORS in children with POTS.

Blood Pressure ; Child ; Fluid Therapy ; Heart Rate ; Humans ; Postural Orthostatic Tachycardia Syndrome ; physiopathology ; therapy ; Predictive Value of Tests ; ROC Curve ; Salts ; Sensitivity and Specificity ; Treatment Outcome

BACKGROUNDThe abnormal blood volume regulation is one of the most important pathogenesis in postural tachycardia syndrome in children. This study was designed to investigate the plasma atrial natriuretic peptide and antidiuretic hormone levels in postural tachycardia syndrome children, and their associations with the changes in heart rate and blood pressure in head-up test.

METHODSTwenty-one postural tachycardia syndrome patients ((12 ± 2) years) and 26 healthy children ((12 ± 1) years) were included. According to blood pressure changes in head-up test, the postural tachycardia syndrome patients were divided into two subgroups: postural tachycardia syndrome with orthostatic hypertension and postural tachycardia syndrome without orthostatic hypertension. The plasma atrial natriuretic peptide and antidiuretic hormone levels were measured using enzyme-linked immunosorbent assay.

RESULTSThe plasma atrial natriuretic peptide level in postural tachycardia syndrome patients was higher than the control (P = 0.004), whereas the difference in plasma antidiuretic hormone level between postural tachycardia syndrome and controls was not significant (P = 0.222). The plasma antidiuretic hormone level of patients suffering from postural tachycardia syndrome with orthostatic hypertension was much higher than that of children having postural tachycardia syndrome without orthostatic hypertension (P < 0.05). In postural tachycardia syndrome patients, the upright max heart rate was positively correlated with the plasma atrial natriuretic peptide level (r = 0.490, P < 0.05) and the upright systolic blood pressure was positively correlated with the plasma antidiuretic hormone levels (r = 0.472, P < 0.05).

CONCLUSIONSThere was a disturbance of plasma atrial natriuretic peptide and antidiuretic hormone in postural tachycardia syndrome children.

Adolescent ; Atrial Natriuretic Factor ; blood ; Case-Control Studies ; Child ; Humans ; Hypertension ; blood ; Postural Orthostatic Tachycardia Syndrome ; blood ; Vasopressins ; blood

BACKGROUNDAcute lymphoblastic leukemia (ALL) and chemotherapy can cause immune imbalance, and gaseous molecule hydrogen sulfide (H2S) can participate in the process of immune response. This study aimed to investigate the immune regulation of H2S in pediatric ALL.

METHODSChildren (n = 78) with ALL admitted during 2010-2013 were included in this study. Two blood samples were collected in period of before chemotherapy, bone marrow remission and two days after chemotherapy, respectively. Serum contents of H2S and cytokines, including interleukin-1β (IL-1β), interleukin-2 (IL-2), interferon-γ (IFN-γ), tumor necrosis factor (TNF-α), interleukin-4 (IL-4), interleukin-6 (IL-6), interleukin-10 (IL-10) and macrophage inflammatory protein-1α (MIP-1α), were detected using ELISA method. Stepwise regression was used to analyze the correlation between H2S and cytokines. Furthermore, human Jurkat cells were cultured in vitro, and nucleoprotein of Jurkat cells and peripheral blood mononuclear cells (PBMCs) were collected, contents of cystathionine γ-lyase (CSE) and certain cytokines were measured by Western blotting.

RESULTSSerum concentrations of H2S, IL-1β, IL-6, IL-10 and MIP-1a in children with ALL were increased significantly (P < 0.01), while concentrations of IL-2, TNF-α, IFN-γ and IL-4 decreased obviously (P < 0.01). In patients after chemotherapy, concentrations of H2S and IL-10 were decreased significantly (P < 0.05), but IL-4 and IFN-γ concentrations increased markedly (P < 0.05). At remission stage, H2S, IL-1β, IL-4, IL-6, IL-10 and MIP-1α concentrations were further decreased markedly (P < 0.05), but concentrations of IL-2, TNF-α and IFN-γ increased again (P < 0.05). Protein contents of CSE, IL-10, IL-4 and IL-2 of PBMCs also increased markedly in children with ALL. Moreover, changes of CSE protein contents of PBMCs were consistent with serum H2S contents, and there were significant correlation between H2S and certain cytokines based on stepwise regression analysis. Furthermore, compared with those of PBMCs group, in vitro study indicated that Jurkat cells of H2S group expressed IFN-γ, IL-10, IL-4 and IL-2 protein increased obviously (P < 0.05), while IL-4, IL-2 and CSE expression of PPG group decreased markedly (P < 0.05).

CONCLUSIONGaseous molecule H2S might participate in the process of immune regulation in pediatric ALL through modulating transcription and expression of cytokines.

Child ; Child, Preschool ; Cystathionine gamma-Lyase ; blood ; Female ; Humans ; Hydrogen Sulfide ; blood ; Interferon-gamma ; blood ; Interleukin-10 ; blood ; Interleukin-1beta ; blood ; Interleukin-2 ; blood ; Interleukin-4 ; blood ; Interleukin-6 ; blood ; Leukocytes, Mononuclear ; metabolism ; Male ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; blood ; Tumor Necrosis Factor-alpha ; blood

Objective To study the change of the renal endogenous hydrogen sulfide (H2 S) pathway in the development of salt-sensitive hypertension in Dah1 rats.Methods Sixteen male Dah1 rats,in accordance with the random number table,were randomly divided into control group and high salt group fed with diet containing 80 g/kg NaCl.After 8 weeks,24 h urine sodium,24 h urinary protein,serum creatinine and serum urea were measured.The microstructural and ultrastructural changes in kidney were observed with light microscope and electronic microscope.The serum and kidney H2S contents were determined by using sulphur-sensitive electrode method.The mRNA levels of cystathionine β-synthase(CBS),cystathionine γ-lyase(CSE) and mercaptopyruvate sulfurtransferase(MPST) in renal tissue were determined by means of real-time polymerase chain reaction(RT-PCR).The protein expressions of CBS,CSE and MPST in renal tissue were detected by using Western blot.Results Compared with control group,high salt group rats had a significant rise in blood pressure,declined renal function,damaged renal structure,segmental glomerular sclero sis,small artery wall thickening,and occlusion of the lumen.Moreover,the endogenous H2S pathway in kidney of Dah1rats with high salt diet was downregulated markedly,demonstrated by the decreased serum and kidney H2S content,the reduced renal CBS,CSE and MPST mRNA expressions and CBS protein expression of kidney tissue.Conclusion The endogenous H2S/CBS pathway is downregulated during the development of salt-sensitive hypertension in Dah1 rats.

Objective To examine the effects of exogenously administered intermedin (IMD,adrenomedullin-2) on arterial blood pressure,cardiac function and the cardiovascular IMD receptor system in spontaneously hypertensive rats (SHRs) as well as to investigate the associated mechanisms.Methods Thirteen week-old male rats were divided in Wistar Kyoto (WKY) group (n =12),SHR group (n =12),IMD group (SHRs infused with IMD 1-47 500 ng/kg per hour,n =12),and ADM group (SHRs infused with adrenomedullin 500 ng/kg per hour,n =12).Results A two-week continuous administration of low dose IMD 1-47 via mini-osmotic pumps markedly reduced blood pressure,the maximal rates of increase and decrease of left-ventricle pressure development (LV ± dp/dtmax),left ventricular systolic pressure and heart rate in SHRs.Furthermore,IMD also inhibited protein over-expression of cardiovascular IMD receptors,myocardial Receptor Activity-Modifying Proteins (RAMP1 and RAMP2),aortic RAMP1,RAMP2,RAMP3,and calcitonin receptor-like receptor (CRLR);suppressed up-regulation of aortic RAMP1,RAMP2,RAMP3 and CRLR gene expression; and markedly elevated the mRNA abundance of myocardial atrial natriuretic peptide (ANP) and myocardial brain natriuretic peptide (BNP).Additionally,IMD 1-47 administration in SHRs increased aortic cAMP concentration and reduced myocardial cAMP concentration.Conclusion These findings support the speculation that IMD,as a cardiovascular active peptide,is involved in blood pressure reduction and cardiac function amelioration during hypertension.The mechanism underlying this effect may involve IMD binding of a receptor complex formed by RAMPs and CRLR,and consequential regulation of cAMP levels and other cardiovascular active factors,such as ANP and BNP.