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Background: Pharmacological inhibition of endothelial arginase-II has been shown to improve endothelial nitric oxide synthase (eNOS) function and reduce atherogenesis in animal models. We investigated whether the endothelial arginase II is involved in inflammatory responses in endothelial cells.Methods: Human endothelial cells were isolated from umbilical veins and stimulated with TNFalpha (10 ng/ml) for 4 hours. Endothelial expression of the inflammatory molecules i.e. vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin were assessed by immunoblotting.Results: The induction of the expression of endothelial VCAM-1, ICAM-1 and E-selectin by TNFalpha was concentration-dependently reduced by incubation of the endothelial cells with the arginase inhibitor L-norvaline. However, inhibition of arginase by another arginase inhibitor S-(2-boronoethyl)-L-cysteine (BEC) had no effects. To confirm the role of arginase-II (the prominent isoform expressed in HUVECs) in the inflammatory responses, adenoviral mediated siRNA silencing of arginase-II knocked down the arginase II protein level, but did not inhibit the up-regulation of the adhesion molecules. Moreover, the inhibitory effect of L-norvaline was not reversed by the NOS inhibitor L-NAME and L-norvaline did not interfere with TNFalpha-induced activation of NF-kappaB, JNK, p38mapk, while it inhibited p70s6k (S6K1) activity. Silencing S6K1 prevented up-regulation of E-selectin, but not that of VCAM-1 or ICAM-1 induced by TNFalpha.Conclusion: The arginase inhibitor L-norvaline exhibits anti-inflammatory effects independently of inhibition of arginase in human endothelial cells. The anti-inflammatory properties of L-norvaline are partially attributable to its ability to inhibit S6K1. [ABSTRACT FROM AUTHOR]

Background: There is a lack of information regarding the provision of parental leave for surgical careers. This survey study aims to evaluate the experience of maternity/paternity leave and views on work-life balance globally., Methods: A 55-item online survey in 24 languages was distributed via social media as per CHERRIES guideline from February to March 2020. It explored parental leave entitlements, attitude towards leave taking, financial impact, time spent with children and compatibility of parenthood with surgical career., Results: Of the 1393 (male : female, 514 : 829) respondents from 65 countries, there were 479 medical students, 349 surgical trainees and 513 consultants. Consultants had less than the recommended duration of maternity leave (43.8 versus 29.1 per cent), no paid maternity (8.3 versus 3.2 per cent) or paternity leave (19.3 versus 11.0 per cent) compared with trainees. Females were less likely to have children than males (36.8 versus 45.6 per cent, P = 0.010) and were more often told surgery is incompatible with parenthood (80.2 versus 59.5 per cent, P < 0.001). Males spent less than 20 per cent of their salary on childcare and fewer than 30 hours/week with their children. More than half (59.2 per cent) of medical students did not believe a surgical career allowed work-life balance., Conclusion: Surgeons across the globe had inadequate parental leave. Significant gender disparity was seen in multiple aspects., (© The Author(s) 2021. Published by Oxford University Press on behalf of BJS Society Ltd. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Competing Interests: Statement The author(s) have no conflicts of interest to disclose.

Introduction: Severe sepsis and septic shock are common conditions with high levels of morbi-mortality surpassing those of coronary heart disease or stroke. The reality of hospital treated sepsis is largely unknown outside of the intensive care unit. We therefore aimed to evaluate the level of compliance with the Surviving Sepsis Campaign 6-hour bundle in a Portuguese emergency department and to relate it to the patient clinical outcomes., Material and Methods: We conducted a retrospective, observational cohort study with 178 severe sepsis/septic shock patients admitted to the intensive and intermediate care unit between January 1st 2012 and December 31st 2012., Results: In the study, period septic shock was diagnosed in 100 patients (56.2%) and severe sepsis in 78 patients (43.8%). Compliance with the sepsis bundle was: (1) 62.9% for lactate measurement; (2) 62.9% for blood cultures before antibiotics; (3) 41.6% for antibiotics in the first 3 hours; (4) 76.4% for fluid administration; (5) 25% for vasopressor administration; (6) 37% for central venous pressure measurement and (7) 39% for central venous oxygen saturation measurement. Full compliance was observed in 22% of the patients. The individual bundle measure - Blood cultures before antibiotics - was significantly associated with a decreased risk of both intensive care unit mortality and 28-day mortality. There was also a trend for an inverse correlation between increased compliance with the full bundle and the intensive care unit and 28-days hospital mortality., Discussion: There was a low compliance with the Surviving Sepsis Campaign 6-hour bundle, a result that replicates the findings in similar international studies. The explanation is complex but it may include the lack of institutional quality monitoring in the emergency department., Conclusions: The compliance with a sepsis resuscitation bundle starting in the emergency department was positively associated with the outcomes of the septic patients. Nonetheless the bundle was unreliably performed.

Period2 (Per2) is an important component of the circadian clock. Mutation of this gene is associated with vascular endothelial dysfunction and altered glucose metabolism. The aim of this study is to further characterize whole body glucose homeostasis and endothelial nitric oxide (NO) production in response to insulin in the mPer2(Brdm1) mice. We show that mPer2(Brdm1) mice exhibit compromised insulin receptor activation and Akt signaling in various tissues including liver, fat, heart, and aortas with a tissue-specific heterogeneous diurnal pattern, and decreased insulin-stimulated NO release in the aortas in both active and inactive phases of the animals. As compared to wild type (WT) mice, the mPer2(Brdm1) mice reveal hyperinsulinemia, hypoglycemia with lower fasting hepatic glycogen content and glycogen synthase level, no difference in glucose tolerance and insulin tolerance. The mPer2(Brdm1) mice do not show increased predisposition to obesity either on normal chow or high fat diet compared to WT controls. Thus, mice with Per2 gene mutation show altered glucose homeostasis and compromised insulin-stimulated NO release, independently of obesity.

Background: Macrophage-mediated chronic inflammation is mechanistically linked to insulin resistance and atherosclerosis. Although arginase I is considered antiinflammatory, the role of arginase II (Arg-II) in macrophage function remains elusive. This study characterizes the role of Arg-II in macrophage inflammatory responses and its impact on obesity-linked type II diabetes mellitus and atherosclerosis., Methods and Results: In human monocytes, silencing Arg-II decreases the monocytes' adhesion to endothelial cells and their production of proinflammatory mediators stimulated by oxidized low-density lipoprotein or lipopolysaccharides, as evaluated by real-time quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. Macrophages differentiated from bone marrow cells of Arg-II-deficient (Arg-II(-/-)) mice express lower levels of lipopolysaccharide-induced proinflammatory mediators than do macrophages of wild-type mice. Importantly, reintroducing Arg-II cDNA into Arg-II(-/-) macrophages restores the inflammatory responses, with concomitant enhancement of mitochondrial reactive oxygen species. Scavenging of reactive oxygen species by N-acetylcysteine prevents the Arg-II-mediated inflammatory responses. Moreover, high-fat diet-induced infiltration of macrophages in various organs and expression of proinflammatory cytokines in adipose tissue are blunted in Arg-II(-/-) mice. Accordingly, Arg-II(-/-) mice reveal lower fasting blood glucose and improved glucose tolerance and insulin sensitivity. Furthermore, apolipoprotein E (ApoE)-deficient mice with Arg-II deficiency (ApoE(-/-)Arg-II(-/-)) display reduced lesion size with characteristics of stable plaques, such as decreased macrophage inflammation and necrotic core. In vivo adoptive transfer experiments reveal that fewer donor ApoE(-/-)Arg-II(-/-) than ApoE(-/-)Arg-II(+/+) monocytes infiltrate into the plaque of ApoE(-/-)Arg-II(+/+) mice. Conversely, recipient ApoE(-/-)Arg-II(-/-) mice accumulate fewer donor monocytes than do recipient ApoE(-/-)Arg-II(+/+) animals., Conclusions: Arg-II promotes macrophage proinflammatory responses through mitochondrial reactive oxygen species, contributing to insulin resistance and atherogenesis. Targeting Arg-II represents a potential therapeutic strategy in type II diabetes mellitus and atherosclerosis. (J Am Heart Assoc. 2012;1:e000992 doi: 10.1161/JAHA.112.000992.).

Aim: The sex hormones 17β-estradiol (βES) and progesterone (PRG) induce rapid non-genomic vasodilator effects which could be protective for the cardiovascular system. The purpose of this study was to analyze the mechanisms underlying their vasodilator effect in rat aortic smooth muscle preparations., Methods: Endothelium-denuded aorta artery rings were prepared from male Wistar rats and incubated in an organ bath. The contractions of the preparation were recorded through isometric transducers. The effects of the hormones on K(+) current and L-type Ca(2+) current (LTCC) were analyzed by using the whole cell voltage-clamp technique in A7r5 cells., Results: Both βES and PRG (1-100 μmol/L) concentration-dependently relaxed the endothelium-denuded aortic rings contracted by (-)-Bay K8644 (0.1 μmol/L) or by KCl (60 mmol/L). The IC(50) values of the two hormones were not statistically different. The K(V) channel blocker 4-aminopyridine (2 mmol/L), BK(Ca) channel blocker tetraethylammonium (1 mmol/L) and K(ATP) channel blocker glibenclamide (10 μmol/L) did not significantly modify the relaxant effect of the hormones. On the other hand, the blockage of the intracellular βES and PRG receptors with estradiol receptor antagonists ICI 182,780 (1 μmol/L) and PRG receptor antagonist mifepristone (30 μmol/L), respectively, did not significantly modify the relaxant action of the hormones. In A7r5 cells, both the hormones (1-100 μmol/L) rapidly and reversibly inhibited the basal and BAY-stimulated LTCC. However, these hormones had no effect on the basal K(+) current., Conclusion: The vasorelaxant effects of βES and PRG are due to the inhibition of LTCC. The K(+) channels are not involved in the effects.

Mammalian target of rapamycin (mTOR)/S6K1 signalling emerges as a critical regulator of aging. Yet, a role of mTOR/S6K1 in aging-associated vascular endothelial dysfunction remains unknown. In this study, we investigated the role of S6K1 in aging-associated endothelial dysfunction and effects of the polyphenol resveratrol on S6K1 in aging endothelial cells. We show here that senescent endothelial cells displayed higher S6K1 activity, increased superoxide production and decreased bioactive nitric oxide (NO) levels than young endothelial cells, which is contributed by eNOS uncoupling. Silencing S6K1 in senescent cells reduced superoxide generation and enhanced NO production. Conversely, over-expression of a constitutively active S6K1 mutant in young endothelial cells mimicked endothelial dysfunction of the senescent cells through eNOS uncoupling and induced premature cellular senescence. Like the mTOR/S6K1 inhibitor rapamycin, resveratrol inhibited S6K1 signalling, resulting in decreased superoxide generation and enhanced NO levels in the senescent cells. Consistent with the data from cultured cells, an enhanced S6K1 activity, increased superoxide generation, and decreased bioactive NO levels associated with eNOS uncoupling were also detected in aortas of old WKY rats (aged 20-24 months) as compared to the young animals (1-3 months). Treatment of aortas of old rats with resveratrol or rapamycin inhibited S6K1 activity, oxidative stress, and improved endothelial NO production. Our data demonstrate a causal role of the hyperactive S6K1 in eNOS uncoupling leading to endothelial dysfunction and vascular aging. Resveratrol improves endothelial function in aging, at least in part, through inhibition of S6K1. Targeting S6K1 may thus represent a novel therapeutic approach for aging-associated vascular disease.

Rapamycin has been reported to enhance tissue factor (TF) expression. The present study investigated roles of mammalian target of rapamycin (mTOR) and its downstream S6K1 in this process. We showed here that, consistent with rapamycin, knocking-down mTOR enhanced thrombin-induced TF mRNA and protein levels, whereas silencing S6K1 mitigated up-regulation of TF protein but not TF mRNA level. The enhanced TF protein level upon mTOR-silencing was further augmented by over-expression of a constitutively active S6K1 mutant and reduced by blocking RhoA, p38(mapk) or NF-kappaB. The results reveal an opposing and uncoupling effect of mTOR and S6K1 in regulating TF expression.

Elevated cellular levels of protein O-linked beta-N-acetylglucosamine (O-GlcNAc) through hexosamine biosynthesis pathway (HBP) are suggested to contribute to cardiovascular adverse effects under chronic hyperglycemic condition associated with oxidative stress and inflammation. Conversely, enhancing O-GlcNAc levels have also been demonstrated being protective against myocardial ischemia/reperfusion injury. We recently demonstrated that hyperglycemia increases oxidative stress and HBP flux in endothelial cells and enhances endothelial expression of vascular adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) in response to tumor necrosis factor-alpha (TNFalpha) through oxidative stress rather than HBP pathway. Here we present further complementary data showing that enhancing O-GlcNAc levels by glucosamine does not mimic hyperglycemia's effect on TNFalpha-induced endothelial VCAM-1 and ICAM-1 expression. Glucosamine however inhibits ICAM-1 (not VCAM-1) expression and induces superoxide generation in the cells. The results further suggest that increased O-GlcNAc levels do not mediate the enhancing effect of hyperglycemia on the endothelial inflammatory responses to TNFalpha. In contrast, it exerts certain anti-inflammatory effects accompanied by pro-oxidative properties. Further work should delineate the exact role of HPB pathway in different aspects of cardiovascular functions, especially those of diabetic cardiovascular complications.

Hexosamine biosynthetic pathway (HBP) accounts for some cardiovascular adverse effects of hyperglycemia. We investigated whether the HBP inhibitor azaserine protects against hyperglycemia-induced endothelial damage dependently of HBP. Human endothelial cells isolated from umbilical veins were exposed either to a high (30.5 mmol/l) or low concentration of glucose (5.5 mmol/l) for 4 days, followed by a stimulation with TNF-alpha (1 ng/ml, 24 h). The blockade of the rate-limiting enzyme glutamine:fructose-6-phosphate amidotransferase inhibited HBP flux and oxidative stress (generation of superoxide and peroxynitrite) under the hyperglycemic condition and prevented the synergistic stimulation of VCAM-1 and ICAM-1 expression by hyperglycemia and TNF-alpha. In the cells cultured under a low-glucose condition when no increased HBP flux occurred, azaserine enhanced the manganese-superoxide dismutase (MnSOD) protein level and also inhibited the oxidative stress and the expression of VCAM-1 and ICAM-1 in response to TNF-alpha. Moreover, the polyphenol resveratrol inhibited the oxidative stress and adhesion molecule expression and did not decrease the HBP flux under the hyperglycemia condition. In addition, in isolated rat aortas exposed to hyperglycemic buffer for 5 h when no significant HBP flux occurred, azaserine upregulated the MnSOD protein level and prevented decreased endothelium-dependent relaxations to acetylcholine. In conclusion, hyperglycemia independently increases oxidative stress and HBP flux, amplifies endothelial inflammation, and impairs endothelial function mainly through oxidative stress and not the HBP pathway. Azaserine protects against hyperglycemic endothelial damage through its antioxidant effect independently of inhibiting HBP pathway.