Violence against sex workers: Correlates and Changes under 'End-Demand' legislation in Canada: A five city study

Canada is among several countries to have implemented 'end-demand' criminalization frameworks for sex work. Drawing on interviews with sex workers (n = 200) in five cities, we employed multivariate logistic regression to identify associations with workplace violence. We also analysed descriptive data on trafficking and on workplace violence under end-demand legislation. In the past 12 months, being unable to call 911 in a safety emergency at work for fear of police detection (Adjusted Odd Ratio AOR: 4.307, 95% Confidence Interval CI: 1.697 -10.927), being unable to screen clients due to fear of police detection (AOR: 2.175, 95% CI: 1.074 -4.405), having experienced anti-sex work housing policy/eviction (AOR: 2.031, 95% CI: 0.897-4.598), and being Indigenous (Adjusted Odd Ratio (AOR): 2.167, 95% Confidence Interval (CI): 1.060-4.428) were all independently associated with workplace violence in the past 12 months. Of those who worked prior to the law change (n = 167), a majority of respondents (80.24% (134)) reported that violence in the workplace had increased or stayed the same compared to the previous criminalization model and 87.43% (n = 146) reported it was harder or the same to get help in an emergency.

Sodium-glucose co-transporter 1 and 2 expression in the mammary artery of patients with bypass surgery: role of the pro-inflammatory response and contribution to oxidative stress

Background

Selective sodium-glucose cotransporter 2 (SGLT2) inhibitors have shown cardiovascular protection independently of glycemic control. Angiotensin II (Ang II) and H2O2 induced the expression of SGLT1 and 2 in cultured endothelial cells and isolated arteries to promote oxidative stress and endothelial dysfunction. However, the expression level and role of SGLT1 and 2 in human arteries remain poorly studied.

Purpose

This study examined the expression level of SGLT1 and 2 in the human internal mammary artery (IMA) obtained from bypass surgery patients, and, if so, determined the underlying mechanism and function.

Methods

IMAs were obtained from 40 bypass surgery patients (age 45 to 82). The expression level of target factors was assessed by Western blot analysis, immunofluorescence staining and RT-PCR, and the level of oxidative stress using dihydroethidium staining. Human kidney was used as a control tissue known to express SGLT1 and 2. Porcine coronary artery endothelial cells (CAEC) were cultured and studied at passage 1.

Results

Western blot analysis of 40 IMA samples indicated a high level of both SGLT1 and 2 in 16 and 17 IMAs, an intermediate level in 8 and 6 IMAs, and a low one in 16 and 17 IMAs, respectively. Immunofluorescence staining of IMA sections indicated that SGLT1 and 2 immunofluorescence signals were observed predominantly in the intima thickening and the media. The expression levels of SGLT1 and 2 were associated with p-p65 NF-kB signals but not angiotensin-converting enzyme (ACE), AT1R, MCP-1, VCAM-1. IMAs with a high expression level of SGLT1 and 2 had a high level of ROS throughout the arterial wall including the intima thickening and endothelium, which was inhibited by the antioxidant N-acetylcysteine, the ACE inhibitor perindoprilat, the AT1R antagonist losartan, and also by the dual SGLT1 and 2 inhibitor sotagliflozin and the selective SGLT2 inhibitor empagliflozin. Pro-inflammatory cytokines mRNA levels of IL-1β, TNF-α and IL-6 were detected in IMAs. Exposure of CAEC to either TNF-α, IL-1β or IL-6 caused a concentration-dependent upregulation of SGLT1 and 2.

Conclusion

The present findings indicate that SGLT1 and 2 expression is observed in some but not all IMAs of bypass surgery patients predominantly in the media, the intima thickening and the endothelium. High expression levels of SGLT1 and 2 are associated with NF-kB activation and oxidative stress that is prevented by a selective SGLT2 inhibitor and by a dual SGLT1/2 inhibitor. Since pro-inflammatory cytokines triggered SGLT1 and 2 expression in endothelial cells, the inflammatory burden of patients appears to be an important trigger regulating SGLT1/2 expression and the subsequent pro-oxidant response prompting pro-inflammatory and pro-thrombotic responses.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): This work was supported by an unrestricted research grant from Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany.

Protective effects of dapagliflozin on vascular remodeling in the carotid artery following balloon injury – potential role of angiotensin and purinergic signaling

Introduction

Sodium-glucose co-transporter 2 (SGLT2) inhibitors have been shown to reduce the risk of cardiovascular events independently of glycemic control. The possibility that SGLT2 inhibitors improve endothelial regeneration and vascular restenosis is unknown.

Purpose

To examine whether dapagliflozin, a selective SGLT2 inhibitor, could prevent neointima thickening induced by balloon injury and, if so, to determine the underlying mechanisms. The effect of dapagliflozin was compared to that of losartan, an angiotensin type 1 receptor (AT1R) antagonist.

Methods

Saline, dapagliflozin (1.5 mg/kg/day), or losartan (30 mg/kg/day) were administered orally for 5 weeks to male Wistar rats. Balloon injury of the left carotid artery was performed 1 week after starting the treatment and sacrificed 4 weeks later. Vascular reactivity was assessed on left (injured) and right (healthy) carotid artery rings. The extent of neointima was assessed by histomorphometric analysis, changes of target factors by immunofluorescence, RT-qPCR and histochemistry.

Results

Dapagliflozin and losartan treatments reduced neointima thickening by 32% and 27%, respectively. Blunted contractile responses to phenylephrine and relaxations to acetylcholine and down-regulation of eNOS were observed in the injured artery. These effects were not modified by the dapagliflozin or the losartan treatments. RT-qPCR investigations indicated an increased in gene expression of inflammatory (IL-1beta, ITGAM, VCAM-1), oxidative (p47phox, p22phox) and fibrotic (TGF-beta1) markers and a decreased of eNOS in the injured carotid. However, these changes were not affected by the pharmacological treatments. By contrast, significant increased levels of AT1R angiotensin receptor and NTPDase1 (CD39) ectonucleotidase were observed in the restenotic carotid artery of the dapagliflozin group. Histochemical analysis evidenced important NTPDase1 activity in the neointima.

Conclusions

Dapagliflozin effectively reduced neointimal thickening. As the contribution of AT1R and P2Y2 ATP receptor in smooth muscle cell proliferation and neointima formation has been reported in the literature, the present data suggest that dapagliflozin prevents restenosis through interfering with angiotensin and/or extracellular nucleotides signaling. SGLT2 transporter represent potential new target for limiting vascular restenosis.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): This work was supported by AstraZeneca

Empagliflozin treatment does not affect the hypertensive response to Ang II administration to rats but decreases oxidative stress in the arterial wall, and endothelial and cardiac dysfunction

Background

Selective sodium-glucose cotransporter 2 (SGLT2) inhibitors have shown cardiovascular protection in type 2 diabetes patients with established cardiovascular disease independently of glycemic control. Angiotensin II (Ang II) and H2O2 have been shown to be strong inducers of the expression of SGLT2 and 1 in endothelial cells promoting oxidative stress and endothelial dysfunction.

Purpose

This study examined the cardiovascular protective effect of empagliflozin (empa) in a normoglycemic experimental model of hypertension in the rat.

Methods

Male Wistar rats received empa (30 mg/kg/day) provided in the diet for 5 weeks. After 1 week, rats underwent sham surgery (sham rats) or surgery with implantation of an osmotic mini-pump infusing Ang II (0.4 mg/kg/d) for 4 weeks. Systolic blood pressure (SBP) was assessed by sphygmomanometry, the cardiac function using echocardiography, the expression level of target proteins by immunofluorescence staining, and the level of oxidative stress using dihydroethidium staining.

Results

Angiotensin II administration increased systolic blood pressure from about 130 to 180 mmHg, which was not affected by the empa treatment. The 4-week Ang II treatment did not significantly affect the systolic cardiac function (cardiac output, left ventricle ejection fraction) but impaired the diastolic function as indicated by a reduced E' and IVRT values, and an increased E/E' value. The Ang II treatment increased significantly the heart and right ventricle weight whereas the left ventricle + septum weight was slightly but not significantly increased. No such functional and structural changes were observed in the Ang II + empa treatment group. An increased immunofluorescence eNOS signal in the endothelium, and a higher level of ROS throughout the aorta wall were observed in the Ang II-treated group, both of which were significantly reduced in the empa + Ang II-treated group. In the Ang II-treated group, the high level of oxidative stress in the aorta was significantly reduced by the AT1 receptor antagonist losartan, the NADPH oxidase inhibitor VAS-2871, the eNOS inhibitor NG-nitro-L-arginine and also to a greater extent by the selective SGLT2 inhibitor empa compared to the dual SGLT1/2 inhibitor sotagliflozin.

Conclusion(s)

The present findings indicate that although the empa treatment did not affect the hypertensive response of rats to Ang II, the SGLT2 inhibitor prevented the deleterious impact of Ang II on the diastolic cardiac function and remodeling, and the upregulation of eNOS expression and oxidative stress in the aorta wall. Thus, these findings highlight the protective potential of empa on the cardiovascular system in a normoglycemic hypertensive experimental model.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Boehringer Ingelheim Pharma GmbH & Co KG (Biberach an der Riss, Germany)

P6266Circulating microparticules of patients with coronary artery disease up-regulate the expression of sodium-glucose cotransporters 1 and 2 in coronary artery endothelial cells: role of angiotensin II

Introduction

Circulating microparticles (MPs) from patients with coronary artery diseases (CAD) have been shown to promote endothelial senescence and dysfunction involving the pro-oxidant local angiotensin system. Sodium-glucose cotransporters (SGLTs)2 inhibitors decreased the risk of cardiovascular disease in patients with type 2 diabetes and this effect appears to be independent of glycemic control. Moreover, high glucose and H2O2 have been shown to cause a redox-sensitive upregulation of SGLT1 and 2 in coronary artery endothelial cells (ECs).

Aim

Therefore, this study examined whether angiotensin II (Ang II, a potent NADPH oxidase-dependent inducer of oxidative stress) and CAD MPs stimulate SGLT1 and 2 expression in ECs, and assessed their role in the induction of endothelial dysfunction.

Methods

ECs were isolated from porcine coronary arteries. The protein expression level was assessed by Western blot analysis and immunocytochemical staining, oxidative stress using dihydroethidium staining, and senescence by senescence-associated beta-galactosidase activity (SA-beta-gal activity). Circulating CAD MPs were collected from blood samples of patients (61–79 year) with established cardiovascular disease.

Results

Control ECs expressed low levels of SGLT1 and SGLT2 proteins. Exposure of ECs to Ang II caused a time- and concentration-dependent increase in the protein level of SGLT1 and SGLT2 with a significant increase observed at concentrations as low as 10 nM. Exposure of ECs to CAD MPs (10 nM PhtdSer eq) from 3/5 patients increased the SGLT1 and SGLT2 protein level. An increased SGLT1 and SGLT2 immunofluorescence signal was also observed in response to Ang II and H2O2. Ang II increased the level of oxidative stress, SA-beta-gal activity, senescence markers (p53, p21 and p16), VCAM-1, MCP-1, tissue factor (TF) and the local angiotensin system (ACE, AT1R), and down-regulated that of eNOS. CAD MPs from 4/5 patients decreased eNOS level and from 5/5 patients increased VCAM-1 level. All the Ang II-induced effects were prevented by the dual SGLT1/2 inhibitor LX-4211 and the selective SGLT2 inhibitor, empagliflozin.

Conclusions

The present findings indicate that CAD MPs and Ang II upregulate the expression of SGLT1 and SGLT2 protein levels in ECs, and that they promote endothelial dysfunction. They further suggest that inhibition of SGLT1 and/or SGLT2 might be an attractive strategy to protect the arterial wall and, hence, the development of cardiovascular diseases.

Acknowledgement/Funding

Unrestricted research grant from Boehringer Ingelheim Pharma GmbH & Co. KG

P6278Ageing is associated with increased endothelial sodium-glucose cotransporter 1 expression at arterial sites at risk promoting enhanced anthocyanin accumulation and improved vascular oxidative stress

Introduction

Ageing is characterized by endothelial dysfunction and vascular oxidative stress affecting initially arterial sites at risk. Anthocyanin-rich products are potent stimulators of the endothelial formation of nitric oxide. Sodium-glucose co-transporter 1 (SGLT1) expression has been shown to be increased by oxidative stress and mediate anthocyanin uptake in endothelial cells.

Purpose

The study determined whether ageing is associated with an upregulation of SGLT1 in arterio-susceptible (aortic arch) and resistant (aorta) sites, and evaluated the vascular SGLT1-mediated anthocyanin uptake. In addition, the impact of a 2-week ingestion of an anthocyanin-rich blackcurrant concentrate (ARBC) by old rats on vascular anthocyanin uptake and oxidative stress, and systolic blood pressure (SBP) was assessed.

Methods

Male Wistar rats (22-month old) were either untreated or treated with ARBC (60 and 120 mg/kg/day) in the drinking water for 2 weeks. SGLT1 expression was assessed by immunofluorescence, anthocyanin accumulation by Neu A reagent using a purified extract (BCE) prepared from ARBC, oxidative stress by dihydroethidium using confocal microscopy, and SBP by tail-cuff sphingomanometry.

Results

SGLT1 immunofluorescence was observed predominantly in the endothelium and was higher in the aortic arch than the aorta in old rats whereas only low levels were observed in young rats (12-week old). Exposure of vascular sections to BCE resulted in anthocyanin uptake exclusively in the endothelium, which was higher in the aortic arch than the aorta, and more pronounced in old than young rats. Anthocyanin uptake induced by BCE in the aorta was markedly reduced by LX4211 (a SGLT1/2 inhibitor) both in old and young rats. A high level of oxidative stress was observed throughout the aortic wall of old compared to young rats, which was inhibited by LX4211. Ingestion of ARBC by old rats resulted in a dose-dependent accumulation of anthocyanins throughout the aorta wall and the aortic arch. The tissue accumulation of anthocyanins was associated with a reduced level of oxidative stress. Ageing was associated with increased SBP by about 8 mmHg, which was reduced by ARBC 60 and 120 mg/kg/day treatment by about 5 and 7 mmHg, respectively.

Conclusion

The present findings indicate that ageing is associated with an upregulation of SGLT1 predominantly in the endothelium and that this effect is more pronounced at the aortic arch than the aorta. The increased endothelial expression level of SGLT1 promoted a greater accumulation of anthocyanins sensitive to LX4211. In addition, a 2-week ingestion of ARBC by old rats resulted in the accumulation of anthocyanins throughout the arterial wall of the aortic arch and aorta, and resulted in a reduced level of oxidative stress and systolic blood pressure. Thus, SGLT1 may be an attractive target to restore vascular protection at arterial sites at risk by promoting endothelial and vascular uptake of anthocyanins.