Basal Blood Research Articles

Effect of Vildagliptin on the Level of P-Glycoprotein Expression in Normal Conditions and Alloxan–Induced Type 2 Diabetes Mellitus

INTRODUCTION: Vildagliptin is one of the drugs of choice in the treatment of type 2 diabetes mellitus (DM). In the literature review, no study has reported the effect of vildagliptin on the expression level of the transporter protein P-glycoprotein (P-gp, ABCB1 protein).
 AIM: To assess the in vivo effects of vildagliptin on the level of Р-gp expression in normal conditions and experimental alloxan-induced type 2 DM.
 MATERIALS AND METHODS: Type 2 DM was induced by a single intravenous injection of freshly prepared alloxan monohydrate solution in citrate buffer (pH = 4.0) at a dose of 80 mg/kg. Glucose content (mmol/L) was determined by the glucose oxidase method using Human kit (Germany) and insulin content (U/mL) by radioimmunoassay technique using Immunotech kit (Czech Republic). As an express method for the determination of glucose levels in the whole blood, OneTouch UltraEasy electrochemical glucose monitor (USA) was used. The level of P-gp expression in rabbit tissues (i.e., jejunum, liver, kidney, and cerebral cortex) was evaluated by the indirect histochemical method. After preliminary treatment, the histological material was embedded in paraffin. Antigens were retrieved before the immune-staining reaction. Then, the sections were incubated with primary antibodies to P-gp (ABCB1 antibody, middle region; 0.1 mL [Aviva Systems Biology ARP51326-P050, USА]). For immune staining, a polymer detection system with a peroxidase label (Leica Microsystems, Germany) was used. The cell nuclei were stained with hematoxylin. Photos of the micropreparation were captured using Canon Power Shot G5 digital camera with 400 magnification. Digital images were analyzed and processed using ImageJ and IHC Profiler plugin designed for quantitative immunohistochemical analysis. The results obtained from healthy animals, animals with alloxan-induced DM, healthy animals administered vildagliptin, and animals with modeled DM administered vildagliptin were compared.
 RESULTS: After day 14 of administration to healthy rabbits and day 5 of vildagliptin discontinuation (5 mg/kg), no statistically significant changes in P-gp expression in the aforementioned tissues and the levels of basal and postprandial insulin and blood glucose were noted. After the 14-day therapy of alloxan-induced type 2 DM with vildagliptin (5 mg/kg), a statistically significant recovery of expression of the P-gp expression in the jejunum, liver, and kidney was reduced due to the underlying pathology. In addition, the values of healthy rabbits and statistically significant normalization of the insulin and blood glucose levels were observed. On day 5 of drug cancellation, significant inhibition of P-gp expression in the jejunum, liver, and kidney was noted again, and there was a significant reduction of postprandial insulin and blood glucose. No significant alterations of ABCB1 protein expression in the hematoencephalic barrier were noted during the studied periods.
 CONCLUSION: The administration of vildagliptin (5 mg/kg) to rabbits with alloxan-induced type 2 DM promotes the recovery of P-gp expression in the jejunum, liver, and kidney, which were reduced due to the underlying pathology. Meanwhile, its administration to healthy animals had no significant effect on the expression of P-gp.

Effect of Short-Time BelAgeTM Prescription on Pregnancy and Risk Preeclampsia

Introduction: The aim was to determine if one month taking BelAgeTM in the second trimester of pregnancy could reduce the risk of preeclampsia. Methods: From April 2019 to July 2020, a non-blinded, prospective, randomized, study was performed inviting women in the second trimester of pregnancy to take 3 g of BelAgeTM once daily for one month. The control group received only the nutritional assessment. Relative risk (RR) to develop preeclampsia with 95% confidence interval (CI) was calculated using the Social Science Statistics online software, considering a significant statistical value a P-value < 0.05. Results: 144 patients from the BelAgeTM group (mean age 23.6 ± 9.7), and 99 from the control group (mean age 22.1 ± 8.6) were included, finding differences basal systolic blood pressure (P = 0.03), final diastolic blood pressure (P = 0.002) and final mean blood pressure (P = 0.001). Preeclampsia was developed by 18 patients in the BelAgeTM group versus ten patients in the control group, RR 1.2 (95% CI, 0.60–2.57, P = 0.57). Conclusion: A short-time BelAgeTM prescription in the second trimester of pregnancy was enough to reduce the DBP, but did not reduce the risk of developing preeclampsia. Keywords: BelAgeTM diastolic blood pressure, preeclampsia, relative risk.

Abstract MP17: Neuropilin-1 Is A Novel Regulator Of Vascular Tone And Blood Pressure

Introduction: Neuropilin-1 (NRP1) is a transmembrane receptor present in vascular smooth muscle cells (VSMC) that mediates the inhibition of Rho signaling by binding the Class 3 Semaphorin (SEMA) ligand SEMA3A. Hypothesis: We hypothesize that loss of NRP1 in VSMC mitigates SEMA3A-induced Rho inhibition, thereby increasing vascular tone and blood pressure in vivo . Methods: Male and female adult mice (8-12 weeks) with inducible, smooth muscle cell-specific deletion of NRP1 (SM22a-Cre ERT2 X Nrp1 flox/flox ) were examined. Following recombination using 4-hydroxy tamoxifen (SM- NRP1 KO), systolic blood pressure (SBP) was measured using a tail cuff and compared to age- and sex-matched mice that did not receive tamoxifen (control). Aortic vascular reactivity and expression of key proteins in the Rho signaling cascade were measured using ex vivo tension myography and western blotting, respectively. Results: SBP was significantly increased in SM- NRP1 KO mice following recombination compared to control mice (SBP: 136.5 ± 10.9 vs 112.9 ± 5.6 mmHg; p=0.0006). Contractile responses in aortas of SM- NRP1 KO mice to phenylephrine (p=0.025), KCl (p=0.012), and the thromboxane agonist U44619 (p=0.019) were significantly enhanced compared to controls. Expression of total myosin light chain and LIMK-2 proteins were increased in SM- NRP1 KO compared to control aortas. In vitro , treatment of murine primary VSMC expressing NRP1 with SEMA3A decreased angiotensin II-induced Rho-GTP activation. Additionally, control and SM- NRP1 KO mice (starting at 2 weeks post-recombination) were administered angiotensin II (490 ng/kg/day) for 4 weeks. While there was no significant difference in SBP at weeks 1 and 2, SM- NRP1 KO mice had significantly lower SBP at weeks 3 and 4 following angiotensin II infusion compared to controls (Week 4 SBP: 150 ± 1.4 vs 130.5 ± 2.5 mmHg; p=0.02), suggesting a low ejection fraction and cardiac dysfunction in these mice. In support of this observation, mRNA expression of atrial natriuretic peptide was increased in hearts of angiotensin II-infused SM- NRP1 KO mice. Conclusion: Our data suggest that VSMC NRP1 regulates basal tone and blood pressure, and that loss of NRP1 causes hypertension and exacerbates cardiac dysfunction.

Abstract P165: Cardiac Capillary Pericytes Constriction Mediates Sleep Deprivation Induced Coronary Microcirculation Dysfunction

Background: Lack of sleep can lead to a variety of adverse cardiovascular events and even sudden death. In most cases, there is no obstructive coronary artery. Coronary microcirculation dysfunction (CMD) is thereby thought to play an important role in cardiovascular events caused by sleep loss. Pericytes regulate blood flow and mediate neurovascular signaling in brain. Here, we hypothesized that cardiac capillary pericytes mediate sleep loss related CMD. Methods and Results: Eight-week-old male C57BL/6J mice were deprived sleep for 6 hours or 72 hours. Cardiac function was detected by transthoracic echocardiography before and after sleep deprivation (SD). Vascular endothelial dyes were perfusion before tissue harvest to evaluate cardiac perfusion. By whole heart clearing, 3D immunolabeling and imaging, the effect of pericytes on cardiac capillary was accessed. Acute 6-hours total sleep deprivation or 72-hours severe sleep deprivation led to decreased cardiac systolic and diastolic dysfunction. Left ventricular end diastolic diameter and left ventricular end systolic diameter increased by 10.12% (0.32 mm of 3.14 mm) and 19.00% (0.31 mm of 1.63 mm). Although coronary flow velocity reserve showed no differences between sleep deprivation and control groups, the basal and maximum coronary blood velocity were increased in acute and severe total sleep deprivation mice, which illustrated CMD. Compared with mice in the control group, the area of cardiac perfusion in the sleep deprivation group was significantly reduced (33.42 ± 4.30% vs. 53.81 ± 7.42%, P < 0.05; SD group, n=7; control group, n=6). Whole mount heart imaging showed pericytes were widely distributed around the microvascular, without difference in regional distribution in the heart. In the area of cardiac perfusion defect, capillary blockages colocalized with pericytes, and the capillary diameter at the pericyte body was significantly reduced in sleep deprived mice (2.01 ± 0.12 μm vs. 2.92 ± 0.07 μm, P < 0.05; SD group, n=10; control group, n=10). Conclusion: Sleep restriction led to cardiac dysfunction and CMD, that pericytes mediated contraction of capillaries might contribute to the process. Cardiac pericytes would be a novel therapeutic target in sleep loss associated heart disease.

The Effect of Body Mass Index on Health-Related Parameters in University Students

Body mass index (BMI) is a significant marker in assessing the health risk factors of an individual. Although, the discovery of BMI is over 200 years, however, its application as a measure of health is fairly new. Hitherto, the prevalence of higher BMI amongst university students is on the rise. Consequently, the present study endeavor to investigate the association of BMI and other health-related parameters namely; per cent body fat, visceral fat, basal metabolic rate (BMR), systolic and diastolic blood pressure, resting heart rate, core and upper muscle endurance, maximum oxygen consumption (V02max) and metabolic equivalent (MET). A total number of 232 university students were enrolled and completed the physical fitness assessments and health indicator measurement of the variables. A multiple Linear Regression (MLR) was used to observe the association of the BMI as the dependent variable with the physical fitness as well as health parameters as independent variables. A significant regression model was obtained F (3.225, 5) = 301.104, P <0.0001, R2 = 0.869 demonstrating that the model has accounted for about 87% variability of the whole dataset. Sensitivity analysis demonstrated that per cent body fat, visceral fat, BMR, as well as VO2max, are the major contributors towards the model prediction P <0.001. Moreover, positive significant relationships were detected between the BMI, per cent body fat, visceral fat, BMR, systolic and diastolic blood pressure whilst negative association between the BMI and performance in upper muscle endurance and VO2max were noted. BMI index could be a potential marker of assessing university students’ health-related risks that would consequently reveal vital information about their overall health status.

496-P: Large-Scale Association of Basal Metabolic Rate and Blood Glucose Outcomes in People with Type 2 Diabetes

Background: Basal metabolic rate (BMR) measures the energy utilized by the body at rest. A growing body of literature reports increased BMR in people with type 2 diabetes (T2D), after controlling for sex, age and weight. We used blood glucose (BG) measurements and BMR values from the Apple Watch collected in the One Drop app, to measure the correlation of BMR and BG for the population as a whole, and for individuals over time. Method: Data included over 48,000 person-months of blood-glucose and BMR measurements from 5,585 people with T2D. BG was self-monitored except for 186 people who provided continuous glucose monitoring (CGM) data through Dexcom’s API. BMR values were summed daily and correlated with 30-day average BG for the study population by linear regression. For each person using CGM, we computed the Pearson correlation coefficient of BMR with Time-in-Range (TIR), and used a random effects model to compute the overall correlation and associated p-value. Results: The correlation coefficient of 30-day average BMR with 30-day average BG was 0.07 (p < 10-6), and of BMR with 30-day TIR was -0.26 (p < 10-6). The average correlation coefficient for individuals of BMR with TIR was -0.23±0.38. After applying the random effects model, the overall adjusted coefficient for individuals was -0.18 (p < 10-6). Conclusion: BMR and BG measurements collected in the One Drop app for 5,585 people with T2D show significant correlation of BMR with monthly BG levels at the population level and for individuals over time. This is among the largest scale analyses of such correlation, and the first one to use highly available BMR measurements from the Apple Watch. Disclosure Y. Wexler: None. D. Goldner: Employee; Self; One Drop.

IMPACT OF LEFT VENTRICULAR DYSFUNCTION ON THE OCCURRENCE OF VENTRICULAR ARRHYTHMIAS AFTER ACUTE ST ELEVATION MYOCARDIAL INFARCTION

Objective: The objective of the study was to compare the incidence of post STEMI ventricular arrhythmias among patients with versus without LV dysfunction. Methodology: This prospective Cohort study was conducted in the department of cardiology of a tertiary care hospital, Isra University Hospital, Hyderabad over a period of eleven months from 1st September 2019 to 31st July 2020 and recruited a total of 95 patients with STEMI. Baseline data (age, gender, social class, and marital status) and clinical data (basal metabolic rate, systolic and diastolic blood pressure, random blood sugar, and LVSD) were recorded in a pre-structured questionnaire and analyzed using Statistical Package for the Social Sciences (SPSS) version 21 to see the comparative incidence of ventricular arrhythmias by applying chi-square test where applicable. Results: Out of total 95 STEMI patients, 53 patients had left ventricular systolic dysfunction (55.7%). The overall incidence of ventricular arrhythmias was 23.1% and it was significantly higher in patients with LVSD as compared to those with normal LV function, 36.3% and 72.7% respectively (p = 0.001). Conclusion: Our study shows that overall burden of ventricular tachyarrhythmias is two times higher in patients with left ventricular systolic dysfunction as compared to normal left ventricular systolic function.

Intradialytic changes in endothelin-1 level and its relation with intradialytic hypertension

Background Intradialytic hypertension (IDH) is a major problem affecting 5–15% of patients with end-stage renal disease on maintenance hemodialysis (HD). We evaluated the changes of endothelin-1 (ET-1) levels during HD and its relation to IDH. Patients and methods We divided 48 stable HD patients into two groups: group I included 24 HD patients with IDH, and group II included 24 HD patients with well-controlled blood pressure (BP). Diabetic patients, patients taking angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARBs), and patients with severe infection, malignancy, or having decompensated liver cell failure were excluded from this study. For all patients, BP measurement was done before HD session and every half an hour throughout the sessions. ET-1 level was measured using enzyme-linked immunosorbent assay technique; three samples (before session, when BP rises during session, and at end of session) were taken from group I patients, and one sample was taken before the session in group II patients. Results Group I had significantly lower dry weight than group II (59.9±16 vs.71.5±11 kg) but a significantly higher ultrafiltration volume (2 vs. 1.5 l). There was a significant positive correlation between basal ET-1 and diastolic blood pressure after dialysis (r=0.51, P Conclusion High ET-1 is a significant risk factor for having IDH, and basal ET-1 level had a significant moderate diagnostic performance in prediction of IDH.

P2565Decreased cardiac pacemaking and attenuated beta-adrenergic response in tric-a knock-out mice

Abstract Background Trimeric intracellular cation (TRIC) channels are expressed on the surface of the sarcoplasmic reticulum and compensate for calcium release from ryanodine receptors. Tric-a knock-out (KO) mice showed diminished calcium release from ryanodine receptors in vascular smooth muscle cells. The cardiac pacemaker is controlled by the surface membrane and intracellular calcium clocks. In spontaneously firing sinus node action potentials, the membrane and calcium clocks work together via numerous interactions modulated by membrane voltage, intracellular calcium release, and protein phosphorylation. Intracellular calcium changes modulate cardiac pacemaking in the sinus node, but the physiological importance of TRIC channels in cardiac rhythm formation is still obscure. Purpose In this study, we aimed to clarify the importance of TRIC channels on cardiac pacemaking using Tric-a KO mice. Methods The expression level of mRNA and proteins in the sinus node was examined by RT-PCR and immunoblotting. Systolic blood pressure was measured with tail-cuff method. Heart rate was measured by ECG, and heart rate variability was examined. The atrial contractile force from isolated hearts was measured with a force transducer. Cardiac action potential and spontaneous sinus rate from isolated hearts were measured with a microelectrode. Isoproterenol was used for sympathetic nerve manipulation. Results Tric-a KO heart showed increased adrenergic β1-receptor expression in immunoblotting. Although there was no significant difference in basal systolic blood pressure between Tric-a KO and wild type (WT) mice, basal heart rate in Tric-a KO mice was significantly lower than that in WT mice (660±10 and 698±10 bpm, n=15 and 19, Tric-a KO mice and WT mice, respectively, p=0.017). Tric-a KO mice showed limited heart rate changes to isoproterenol (24±6 and 99±15 bpm, n=9 and 10, Tric-a KO mice and WT mice, respectively, p<0.001). In the action potential recordings, Tric-a KO atria showed only limited sinus rate changes to isoproterenol (35±9 and 71±10 bpm, n=8 and 6, Tric-a KO mice and WT mice, respectively, p=0.038). WT mice and Tric-a KO mice atrial contractile force showed dose-dependent changes in response to isoproterenol (10–100 nM), but Tric-a KO mice atria showed limited contractile force changes to isoproterenol (116 and 169%, n=7 and 6, Tric-a KO mice and WT mice, respectively, p<0.01). In heart rate variability, Tric-a KO mice showed unstable RR intervals and longer standard deviation of RR intervals than WT mice. Conclusion Tric-a KO mice showed decreased cardiac pacemaking in the sinus node and attenuated responses to beta-adrenergic stimulus, which indicates the involvement of TRIC channels in cardiac rhythm formation and sympathetic nerve regulation.

P4469Reduced myocardial perfusion reserve in type 2 diabetes is caused by increased rest perfusion as well as decreased maximal perfusion during stress

Abstract Background Reduced myocardial perfusion reserve is a well-known complication in patients with type 2 diabetes mellitus (T2DM). Furthermore, reduced myocardial perfusion reserve has been linked to the development of diastolic dysfunction, a key characteristic in diabetic cardiomyopathy. However, it is not fully explored whether a decrease in perfusion during stress or an increase in perfusion during rest is responsible for this reduction in myocardial perfusion reserve, nor is it clear what causes these changes. Purpose The purpose of this study was to examine differences in myocardial perfusion in rest and during stress in patients with T2DM compared to healthy control subjects, and to identify potential predictors for changes in perfusion during rest and stress among patients with T2DM. Methods 200 patients with T2DM and 25 healthy volunteers matched for age and sex underwent a comprehensive cardiac MRI protocol including gadolinium first-pass perfusion during rest and stress (adenosine infusion 140 mg/min–1/kg–1). Perfusion was measured on a per-segment basis based on the AHA model and averaged to calculate global perfusion index both during rest and stress. Any areas with infarctions and/or significant perfusion defects were excluded from the analysis. Backwards stepwise multiple linear regression was performed to identify predictors for perfusion changes during rest and stress in patients with T2DM. Variables with P<0.1 in a univariate analysis were included into the models. Results Patients with T2DM had significantly higher rest perfusion index (0.135±0.024 vs. 0.120±0.016; P=0.001) and significantly lower stress perfusion index (0.174±0.041 vs. 0.225±0.027; P<0.001) compared to healthy volunteers. In a multiple linear regression model among patients with T2DM female sex (P<0.001) was associated with increased rest perfusion. In a similar analysis for stress perfusion, diabetes duration (P=0.01), albuminuria (P<0.001) and the presence of ischaemic heart disease (P<0.001) were associated with reduced myocardial stress perfusion index in patients with T2DM. Conclusion In patients with T2DM reductions in myocardial perfusion reserve is caused by a combination of increased basal myocardial blood flow and a decrease in maximal blood flow during stress. Decreased stress perfusion is associated with coronary vascular disease and the diabetic complication albuminuria related to renal microvascular disease. Stress perfusion also decreased with increasing duration of T2DM. This suggest that the coronary microcirculation is gradually damaged in patients with T2DM and that the mechanism responsible is similar to that causing renal microvascular damage. Acknowledgement/Funding Local science committee of Region Zealand, Regional science committee of Region Zealand, The Danish Heart Association

Anesthetic evaluation of a novel phospholipid-free 1% propofol microemulsion formulation in dogs

A novel four-week stable experimental formulation of propofol lacking phospholipids (PMICRO) was assessed as an anesthetic agent in dogs and compared to the customary preparation of propofol that contains phospholipids (PMACRO). Forty healthy mixed-breed dogs were included in this study and randomly assigned (blocking by sex and age), to receive 5 mg/kg of one of these two pharmaceutical propofol preparations, by intravenous injection. Basal and post anesthetic blood biochemical parameters were measured. Also, cardiovascular and respiratory rates were recorded. Onset, duration and recovery from anesthesia, were documented as well. Overall, IV administration of PMICRO induces a short duration anesthesia with rapid recovery in a similar manner to anesthesia achieved with the customary propofol preparation (PMACRO). Because PMICRO lacks phospholipids, it may allow a longer storage time, decreasing the likeliness of accidental administration of contaminated propofol.

Abstract 077: Proximal Tubule-Specific Deletion of the NHE3 (na + /h + Exchanger 3) in the Kidney Attenuates Angiotensin II-Induced Hypertension in Mice

The Na + /H + exchanger 3 (NHE3), a ~85 kDa protein encoded by the SLC9A3 gene, is the most important Na + transporter in the proximal tubules of the kidney. Angiotensin II (ANG II) is well-recognized to increase proximal tubule Na + reabsorption by stimulating NHE3 expression and activity in the proximal tubules. However, a direct cause and effect relationship between ANG II and NHE3 in the proximal tubules in ANG II-induced hypertension has not been determined previously. The present study directly tested the hypothesis that NHE3 in the proximal tubules of the kidney is required for the development of ANG II-induced hypertension using proximal tubule-specific NHE3 knockout mice (PT- Nhe3 -/- ). Specifically, PT- Nhe3 -/- mice were generated using the SGLT2-Cre / Nhe3 loxlox approach, whereas ANG II-induced hypertension was studied in 12 groups (n=5-12 per group) of adult male and female wild-type (WT) and PT- Nhe3 -/- mice. Under basal conditions, systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP) were significantly lower in male and female PT- Nhe3 -/- than WT mice ( P <0.01). A high pressor, 1.5 mg/kg/day, i.p., or a slow pressor dose of ANG II, 0.5 mg/kg/day, i.p., for 2 weeks significantly increased SBP, DBP, and MAP in male and female WT mice ( P <0.01), but the hypertensive response to ANG II was markedly attenuated in male and female PT- Nhe3 -/- mice ( P <0.01). ANG II impaired the pressure-natriuresis response in WT mice, whereas proximal tubule-specific deletion of NHE3 improved the pressure-natriuresis response in ANG II-infused PT- Nhe3 -/- mice ( P <0.01). AT 1 receptor blocker losartan completely blocked ANG II-induced hypertension in both WT and PT- Nhe3 -/- mice ( P <0.01). However, inhibition of nitric oxide synthase with L-NAME had no effect on ANG II-induced hypertension in WT or PT- Nhe3 -/- mice (n.s.). Furthermore, ANG II-induced hypertension was significantly attenuated by an orally absorbable NHE3 inhibitor AVE0657. In conclusion, NHE3 in the proximal tubules of the kidney is required for the full development of ANG II-induced hypertension. Our results suggest that NHE3 in the proximal tubules may be therapeutically targeted to treat hypertension induced by ANG II or associated with increased NHE3 expression in the proximal tubules.

Abstract P2016: Proximal Tubule-Specific Knockout of Angiotensin II Type 1a Receptors in the Kidney Augments the Natriuretic Response to Angiotensin III in Mice

Angiotensin III (ANG III), a major metabolite of the potent vasopressor hormone ANG II, reportedly binds and activates AT 2 receptors to oppose the AT 1 receptor-mediated antinatriuretic effect of ANG II in the proximal tubules of the kidney. The present study tested the hypothesis that global ( Agtr1a -/- ) or proximal tubule-specific deletion of AT 1a receptors in the kidney (PT- Agtr1a -/- ) attenuates the blood pressure, but augments renal Na + excretory responses to ANG III in mice. Proximal tubule AT 1a receptor knockout mice (PT- Agtr1a -/- ) were generated using the Sglt2-Cre/ Agtr1a -floxed approach. Adult male wild-type littlemates (WT), global ( Agtr1a -/- ), and PT- Agtr1a -/- mice (n =7-10 for each group) were anesthetized and infused with saline or increasing doses of ANG III, at 10, 50, and 100 ng/min, i.v ., respectively, for 60 min each. An additional group of PT- Agtr1a -/- mice (n=7) was infused with ANG III at 1.5 mg/kg/day, i.p ., via osmotic minipump for 2 weeks. Basal systolic, diastolic, and mean arterial blood pressure were significantly lower ( p <0.01), whereas 24 h urinary Na + excretion was significantly higher in Agtr1a -/- and PT- Agtr1a -/- than WT mice ( p <0.01). ANG III significantly increased systolic blood pressure from 82 ± 5 mmHg to 116 ± 8 mmHg in anesthetized WT mice (n=8, p <0.01 vs. baseline), and from 75 ± 3 mmHg to 109 ± 6 mmHg in anesthetized PT- Agtr1a -/- mice (n=10, p <0.01 vs. baseline). There was no significant difference in the net pressor response to ANG III between WT and PT- Agtr1a -/- mice. A similar pressor effect to ANG III was confirmed in conscious PT- Agtr1a -/- mice (Basal: 97 ± 2 mmHg vs. ANG III: 111 ± 5 mmHg, n=7, p <0.05). Global deletion of AT 1a receptors completely blocked the pressor effect of ANG III in Agtr1a -/- mice (n=7, p <0.05 vs. WT or PT- Agtr1a -/- mice). In WT mice, ANG III induced small, but significant, antinatriuretic responses at 10 and 50 ng/min ( p <0.05), respectively. Conversely, ANG III induced small, but significant, natriuretic responses at 50 and 100 ng/min in PT- Agtr1a -/- mice ( p <0.05). These results suggest that the pressor effect of ANG III is mediated by systemic AT 1a receptors, whereas the natriuretic effect of ANG III in PT- Agtr1a -/- mice may involve AT 2 receptors in the proximal tubules of the kidney.

Abstract P3018: Sirt3 Depletion in Human Essential Hypertension is Linked to Vascular Inflammation and Oxidative Stress While Endothelial Specific Sirt3 Depletion in Mice Promotes Vascular Dysfunction and Increases Hypertension

Hypertension represents a major risk factor for stroke, myocardial infarction, and heart failure and affects 30% of adult population. Vascular dysfunction is crucial in hypertension pathophysiology and exhibits bidirectional relationship. Metabolic disorders and oxidative stress contribute to vascular dysfunction, and mitochondrial deacetylase Sirt3 is critical in the regulation of metabolic and antioxidant functions. We hypothesized that reduced Sirt3 expression contributes to vascular dysfunction and essential hypertension. We studied Sirt3 in arterioles from human mediastinal fat in patients with essential hypertension compared with normotensive subjects. Pathophysiological role of vascular Sirt3 depletion was studied in mice with tamoxifen-inducible endothelial specific Sirt3 depletion (Ec Sirt3KO ). For the first time, we showed a 40% decrease in vascular Sirt3 level and 400% increase in SOD2 acetylation in hypertensive subjects which was linked to increased oxidative stress measured by superoxide overproduction and vascular inflammation due to elevated NfKB activity, VCAM, ICAM and MCP-1 levels. Interestingly, global Sirt3 depletion in mice increases blood pressure, inactivates key mitochondrial antioxidant SOD2 due to acetylation, increases vascular p65, VCAM, ICAM and MCP1, and increased T cell infiltration in kidney, induces cell-senescence and promotes vascular aging while global Sirt3 overexpression prevents these deleterious effects. We tested if Ec Sirt3KO mice have vascular dysfunction and hypertension. Both basal and angiotensin II-induced blood pressure was increased in Ec Sirt3KO mice accompanied by endothelial dysfunction and vascular O 2 • overproduction. Treatment of Ec Sirt3KO mice with SOD2-mimetic mitoTEMPO reduced vascular inflammation, markers of cell-senescence and vascular aging to the wild-type control levels while treatment of Ang II-infused Ec Sirt3KO mice partially rescues from vascular inflammation and attenuates accelerated vascular aging. We suggest that Sirt3 depletion in hypertension promotes both endothelial oxidative stress and metabolic dysfunction. Our data support a therapeutic potential of targeting Sirt3 expression in vascular dysfunction and hypertension.

NADI SHODHANA PRANAYAMA AND ITS IMPACT ON PARAMETERS OF CARDIOVASCULAR, PULMONARY, AND BRAIN FUNCTIONS

Background: Practice of pranayama has been recognized to control cardiac autonomic status with an improvement in cardio-respiratory functions.
 Objective: To determine impact of Nadi-shodana pranayama practice for 20 minutes on heart rate, systolic and diastolic blood pressure, peak expiratory flow rate.
 Methods: Ninety normal healthy subjects aged between 17-20 years of first year MBBS course volunteered for this study out of total 150. Among them 40 were females and 50 were males. They did not have any previous training in Pranayama. All the selected physiological parameters were measured before and after performing ‘Nadi-shodhana Pranayama’. Epi-info 7 was used for analysis.
 Results: Following nadi-shodhana pranayama a significant decline in basal heart rate and systolic blood pressure was observed. Peak expiratory flow rate was significantly improved (P<0.01). No significant changes in respiratory and other cardiovascular parameters were seen.
 Conclusion: Nadi-shodhana Pranayama swiftly alters cardiopulmonary response. Further studies on a larger sample size need to illustrate the underlying mechanisms involved in this alteration.
 Keywords: Nadi-shodhana pranayama, heart rate, blood pressure, peak expiratory flow rate.

104-OR: Glucoregulatory Effects of Hypothalamic Glucocorticoid Action In Vivo

Diabetes is characterized by dysregulated glucose homeostasis that leads to hyperglycemia, due in part to increased hepatic glucose production (GP) and insulin resistance. Excessive levels and/or action of glucocorticoids (GCs) are associated with obesity, insulin resistance, and hyperglycemia. We aim to delineate a mechanism of GC action in the mediobasal hypothalamus (MBH) that modulates GP in normal and pre-obese rodents. Male SD rats underwent stereotaxic MBH bilateral cannulation and intravenous (iv) and intraarterial catheterization to enable simultaneous direct infusions into the MBH, iv infusions, and blood sampling, respectively. Mildly hyperinsulinemic-euglycemic clamps with tracer dilution methodology combined with MBH GC infusion ± GC receptor (GR) inhibition enables measurement of GP and utilization while assessing MBH GC interaction with its MBH receptors independent of changes in plasma insulin, glucagon, and glucose levels. MBH GC infusion potently stimulates GP and lowers the requirement for exogenous glucose infusion without altering glucose utilization. This effect is mediated via GRs since co-infusion of GR antagonist mifepristone, or a HSP90 inhibitor, negates the ability of MBH GCs to increase GP. MBH GCs similarly increased glucose excursions during iv glucose tolerance tests, which was reversed with concomitant MBH mifepristone infusion. Rats fed with high fat diet (HFD) for 3 days had altered glucose kinetics and increased basal plasma corticosterone, insulin, and blood glucose levels without changes in body weight. Chronic MBH GR inhibition with MBH GR shRNA lowered GP compared to MBH mismatch control HFD rats with MBH vehicle infusions, suggesting that blocking excessive MBH GC action resulting from HFD-feeding attenuates GP to improve glucose homeostasis. We provide novel evidence that MBH GC action modulates GP in healthy and pre-obese rats. Importantly, targeted inhibition of MBH GC action may help improve glucose regulation in obesity-related metabolic disease. Disclosure E. Beaulieu-Bayne: None. M. Cardoso: None. H. Kim: None. S. Yang: None. J.T. Yue: None. Funding Diabetes Canada; Natural Sciences and Engineering Research Council of Canada; Alberta Diabetes Institute; Canadian Institutes of Health Research

1081-P: Incidence of Hypoglycemia within 24 Hours of Hospital Admission in Patients Using Insulin Pumps

Background: Insulin pumps have become an increasingly popular alternative to traditional forms of insulin therapy for patients with type 1 and type 2 diabetes. Despite the increasing prevalence of insulin pumps, the safety of their use in hospitalized patients has not been well studied. In this study, we aim to determine the incidence of hypoglycemia in hospitalized patients using insulin pumps within 24 hours of admission prior to any adjustments of their insulin pump settings. Methods: This is a retrospective analysis of adult patients with diabetes (type 1 and 2) who used insulin pumps during the first 24 hours of admission to NYU Winthrop Hospital and did not make any adjustments to the pump settings during that time. Patients <18 years of age, pregnant patients and those who were electively admitted for surgery were excluded from this study. Demographic data and clinical data were collected, which included the presence of steroid use, total daily dose of basal insulin, creatinine level, HbA1c level, and serum and capillary blood glucose values. Hypoglycemia was defined as blood glucose <70mg/dL and severe hypoglycemia was defined as blood glucose <40mg/dL. Results: Two hundred and fifty-seven patients were included in the study. The mean age was 56 years, 152 (59%) patients were male, and 130 (55%) had type 1 diabetes. The mean hemoglobin A1c was 7.9%. A total of 2097 finger stick blood glucose values were obtained, and 1290 (62%) were <180 mg/dL. There were 88 episodes of hypoglycemia (4.1% of all finger stick blood glucose values) and 2 episodes of severe hypoglycemia (0.1% of all finger stick blood glucose values). Conclusion: Insulin pumps are safe and effective for the treatment of both type 1 and type 2 diabetes in the first 24 hours of hospital admission. Disclosure A. Halstrom: None. I. Moledina: None. V. Peragallo-Dittko: None. K. Ancona: None. S. Islam: None. G. Rothberger: None. S.P. Klek: None.

Clinical characteristics of postprandial hypotension in elderly patients with coronary heart disease

Objective To observe the incidence, clinical characteristics, related factors, adverse events during hospitalization and short-term prognosis of postprandial hypotension (PPH) in elderly patients with coronary heart disease. Methods One hundred and sixty-eight elderly patients with coronary heart disease hospitalized in the Department of Cardiology, Second Hospital of Hebei Medical University from January 2014 to January 2015 were selected as the research subjects.They were monitored by 24 h ambulatory blood pressure monitoring.According to the diagnostic criteria of PPH, they were divided into postprandial hypotension group (PPH group) 34 cases and non-postprandial hypotension group (NPPH group) 134 cases.The clinical characteristics, risk factors related to PPH, occurrence of adverse events and prognosis of all-cause death, cardiovascular and cerebrovascular adverse events were compared between the two groups. Results Among 168 elderly patients with coronary heart disease, thirty-four patients had PPH, and the incidence rate was 20.2%(34/168). The average systolic blood pressure before meals in PPH group was (139.8±18.6) mmHg (1 mmHg=0.133 kPa). The proportion of taking calcium antagonists was 50.0% (17/34) higher than that in NPPH group (127.4±13.2)mmHg, 27.6% (37/134). The difference between the two groups was statistically significant(t=6.463, χ2=6.232, P<0.05). PPH was higher in breakfast and dinner than in lunch; the higher the basal systolic blood pressure level, the higher the incidence of PPH.Logistic regression analysis showed that the basal systolic blood pressure level and age were positively correlated with the occurrence of PPH (r=0.301, r=0.208, P<0.05). Follow-up for 26 months showed that the incidence of all-cause death and cerebrovascular events in PPH group was higher than that in NPPH group (χ2=5.800, 11.560, P<0.05). Conclusion The incidence of PPH in elderly patients with coronary heart disease during hospitalization is 20.2%.Breakfast and dinner at three meals are prone to PPH.Older age and high systolic blood pressure level will increase the incidence of PPH.PPH will increase the incidence of mid-term all-cause death and cerebrovascular events. Key words: Postprandial hypotension; Coronary heart disease; Prognosis

Basal blood DHEA-S/cortisol levels predicts EMDR treatment response in adolescents with PTSD

Objective: In literature, recent evidence has shown that the hypothalamic–pituitary–adrenal (HPA) axis can be dysregulated in patients with post-traumatic stress disorder (PTSD) and HPA axis hormones may predict the psychotherapy treatment response in patients with PTSD. In this study, it was aimed to investigate changing cortisol and DHEA-S levels post-eye movement desensitization and reprocessing (EMDR) therapy and the relationship between treatment response and basal cortisol, and DHEA-S levels before treatment.Method: The study group comprised 40 adolescents (age, 12–18 years) with PTSD. The PTSD symptoms were assessed using the Child Depression Inventory (CDI) and Child Post-traumatic Stress Reaction Index (CPSRI) and the blood cortisol and DHEA-S were measured with the chemiluminescence method before and after treatment. A maximum of six sessions of EMDR therapy were conducted by an EMDR level-1 trained child psychiatry resident. Treatment response was measured by the pre- to post-treatment decrease in self-reported and clinical PTSD severity.Results: Pre- and post-treatment DHEA-S and cortisol levels did not show any statistically significant difference. Pre-treatment CDI scores were negatively correlated with pre-treatment DHEA-S levels (r: −0.39). ROC analysis demonstrated that the DHEA-S/cortisol ratio predicts treatment response at a medium level (AUC: 0.703, p: .030, sensitivity: 0.65, specificity: 0.86).Conclusion: The results of this study suggested that the DHEA-S/cortisol ratio may predict treatment response in adolescents with PTSD receiving EMDR therapy. The biochemical parameter of HPA-axis activity appears to be an important predictor of positive clinical response in adolescent PTSD patients, and could be used in clinical practice to predict PTSD treatment in the future.

Prevalence and severity of syndrome Z in women with metabolic syndrome on waiting list for bariatric surgery: a cross-sectional study

BackgroundIn recent years, obesity has become one of the most important public health problems in the world, with a growing prevalence in both developed and developing countries. Recent studies show that sleep disturbances, especially obstructive sleep apnoea (OSA) may be a manifestation of metabolic syndrome (MetS). Although the association of OSA with the MetS is largely attributed to obesity, the exact pathophysiological mechanisms and their individual characteristics still need to be identified. This study investigated the prevalence and severity of syndrome Z in obese women with MetS on waiting list for bariatric surgery.MethodsIn this double-center cross-sectional study, female patients aged ≥18 years, stage III severe obesity with MetS, on waiting list for bariatric surgery were recruited. The diagnosis for MetS was made according to the criteria of the national cholesterol education program, adult treatment panel III. Clinical, anthropometric, demographic, biochemistry, and sleep measurements were collected. Correlations between continuous variables with sleep parameters were performed using the Pearson correlation test or Spearman correlation test.ResultsThe mean age of 83 patients was 44.8 ± 11.2 years and mean BMI was 42.6 ± 8.1 kg/m2. There was a significant correlation between OSA and metabolic score (r = 0.336; P = 0.002), neck circumference (r = 0.218; P = 0.048), basal systolic blood pressure (r = 0.280; P = 0.01), total cholesterol (r = 0.277; P = 0.011) and abdomen circumference (r = 0.284; P = 0.009). The mean values of excessive daytime sleepiness were 10.5 ± 7 demonstrating a value considered normal for its presence. However, a high risk for OSA was observed in practically the entire population. It was observed that the prevalence of Syndrome Z (75.9%) increased significantly according to apnoea hypopnoea index (AHI) (P for trend <0.0000). A prevalence of 27.71% for mild OSA, 20.48% for moderate OSA, and 27.71% for severe OSA was observed. An association of AHI severity with all components of MetS was also observed.ConclusionsWe can conclude that syndrome Z presents a high prevalence in a female population with MetS and a considerable severity according to the presence of OSA. Therefore, patients with MetS should be investigated for the presence of sleep disorders.Trial registration The study has been registered on ClinicalTrials.gov NCT02409160 and followed the standards of The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement: guidelines for reporting observational studies