Inflammation, glucose, and vascular cell damage: the role of the pentose phosphate pathway.

BACKGROUND: Hyperglycemia is acknowledged as a pro-inflammatory condition and a major cause of vascular damage. Nevertheless, we have previously described that high glucose only promotes inflammation in human vascular cells previously primed with pro-inflammatory stimuli, such as the cytokine interleukin (IL)1ß. Here, we aimed to identify the cellular mechanisms by which high glucose exacerbates the vascular inflammation induced by IL1ß. METHODS: Cultured human aortic smooth muscle cells (HASMC) and isolated rat mesenteric microvessels were treated with IL1ß in medium containing 5.5-22 mmol/L glucose. Glucose uptake and consumption, lactate production, GLUT1 levels, NADPH oxidase activity and inflammatory signalling (nuclear factor-κB activation and inducible nitric oxide synthase expression) were measured in HASMC, while endothelium-dependent relaxations to acetylcholine were determined in rat microvessels. Pharmacological inhibition of IL1 receptors, NADPH oxidase and glucose-6-phosphate dehydrogenase (G6PD), as well as silencing of G6PD, were also performed. Moreover, the pentose phosphate pathway (PPP) activity and the levels of reduced glutathione were determined. RESULTS: We found that excess glucose uptake in HASMC cultured in 22 mM glucose only occurred following activation with IL1ß. However, the simple entry of glucose was not enough to be deleterious since over-expression of the glucose transporter GLUT1 or increased glucose uptake following inhibition of mitochondrial respiration by sodium azide was not sufficient to trigger inflammatory mechanisms. In fact, besides allowing glucose entry, IL1ß activated the PPP, thus permitting some of the excess glucose to be metabolized via this route. This in turn led to an over-activation NADPH oxidase, resulting in increased generation of free radicals and the subsequent downstream pro-inflammatory signalling. Moreover, in rat mesenteric microvessels high glucose incubation enhanced the endothelial dysfunction induced by IL1ß by a mechanism which was abrogated by the inhibition of the PPP. CONCLUSIONS: A pro-inflammatory stimulus like IL1ß transforms excess glucose into a vascular deleterious agent by causing an increase in glucose uptake and its subsequent diversion into the PPP, promoting the pro-oxidant conditions required for the exacerbation of pro-oxidant and pro-inflammatory pathways. We propose that over-activation of the PPP is a crucial mechanism for the vascular damage associated to hyperglycemia.

Soluble DPP4 induces inflammation and proliferation of human smooth muscle cells via protease-activated receptor 2.

DPP4 is an ubiquitously expressed cell-surface protease that is shedded to the circulation as soluble DPP4 (sDPP4). We recently identified sDPP4 as a novel adipokine potentially linking obesity to the metabolic syndrome. The aim of this study was to investigate direct effects of sDPP4 on human vascular smooth muscle cells (hVSMCs) and to identify responsible signaling pathways. Using physiological concentrations of sDPP4, we could observe a concentration-dependent activation of ERK1/2 (3-fold) after 6h, which remained stable for up to 24h. Additionally, sDPP4 treatment induced a 1.5-fold phosphorylation of the NF-κB subunit p65. In accordance with sDPP4-induced stress and inflammatory signaling, sDPP4 also stimulates hVSMC proliferation. Furthermore we could observe an increased expression and secretion of pro-inflammatory cytokines like interleukin (IL)-6, IL-8 and MCP-1 (2.5-, 2.4- and 1.5-fold, respectively) by the sDPP4 treatment. All direct effects of sDPP4 on signaling, proliferation and inflammation could completely be prevented by DPP4 inhibition. Bioinformatic analysis and signaling signature induced by sDPP4 suggest that sDPP4 might be an agonist for PAR2. After the silencing of PAR2, the sDPP4-induced ERK activation as well as the proliferation was totally abolished. Additionally, the sDPP4-induced upregulation of IL-6 and IL-8 could completely be prevented by the PAR2 silencing. In conclusion, we show for the first time that sDPP4 directly activates the MAPK and NF-κB signaling cascade involving PAR2 and resulting in the induction of inflammation and proliferation of hVSMC. Thus, our in vitro data might extend the current view of sDPP4 action and shed light on cardiovascular effects of DPP4-inhibitors.

The interleukin-1 receptor antagonist anakinra improves endothelial dysfunction in streptozotocin-induced diabetic rats.

BACKGROUND: Endothelial dysfunction is a crucial early phenomenon in vascular diseases linked to diabetes mellitus and associated to enhanced oxidative stress. There is increasing evidence about the role for pro-inflammatory cytokines, like interleukin-1ß (IL-1ß), in developing diabetic vasculopathy. We aimed to determine the possible involvement of this cytokine in the development of diabetic endothelial dysfunction, analysing whether anakinra, an antagonist of IL-1 receptors, could reduce this endothelial alteration by interfering with pro-oxidant and pro-inflammatory pathways into the vascular wall. RESULTS: In control and two weeks evolution streptozotocin-induced diabetic rats, either untreated or receiving anakinra, vascular reactivity and NADPH oxidase activity were measured, respectively, in isolated rings and homogenates from mesenteric microvessels, while nuclear factor (NF)-κB activation was determined in aortas. Plasma levels of IL-1ß and tumor necrosis factor (TNF)-α were measured by ELISA. In isolated mesenteric microvessels from control rats, two hours incubation with IL-1ß (1 to 10 ng/mL) produced a concentration-dependent impairment of endothelium-dependent relaxations, which were mediated by enhanced NADPH oxidase activity via IL-1 receptors. In diabetic rats treated with anakinra (100 or 160 mg/Kg/day for 3 or 7 days before sacrifice) a partial improvement of diabetic endothelial dysfunction occurred, together with a reduction of vascular NADPH oxidase and NF-κB activation. Endothelial dysfunction in diabetic animals was also associated to higher activities of the pro-inflammatory enzymes cyclooxygenase (COX) and the inducible isoform of nitric oxide synthase (iNOS), which were markedly reduced after anakinra treatment. Circulating IL-1ß and TNF-α levels did not change in diabetic rats, but they were lowered by anakinra treatment. CONCLUSIONS: In this short-term model of type 1 diabetes, endothelial dysfunction is associated to an IL-1 receptor-mediated activation of vascular NADPH oxidase and NF-κB, as well as to vascular inflammation. Moreover, endothelial dysfunction, vascular oxidative stress and inflammation were reduced after anakinra treatment. Whether this mechanism can be extrapolated to a chronic situation or whether it may apply to diabetic patients remain to be established. However, it may provide new insights to further investigate the therapeutic use of IL-1 receptor antagonists to obtain vascular benefits in patients with diabetes mellitus and/or atherosclerosis.

Case-control study assessing the impact of COVID19 in advanced kidney cancer patients treated with antiangiogenics or immunotherapy: the COVID-REN study.

BACKGROUND: Cancer is a risk factor for developing severe COVID19. Additionally, SARS-CoV2 has a special tropism for renal cells and complications like thrombosis or cytokine storm could be enhanced by standard treatments in kidney cancer (i.e., antiangiogenics or immunotherapy). Thus, understanding the impact of COVID19 in patients with this tumor is key for their correct management. METHODS: We designed a retrospective case-control study comparing the outcome of three groups of advanced kidney cancer patients on systemic treatment: cohort A (developed COVID19 while on antiangiogenics), cohort B (developed COVID19 while on immunotherapy) and cohort C (non-infected). Matching factors were age, gender, and treatment. RESULTS: 95 patients were recruited in 16 centers in Spain from September 2020 to May 2021. Finally, 85 were deemed as eligible (23 cohort A, 21 cohort B, 41 cohort C). Patients with COVID required more dose interruptions (25 vs. six) and hospitalizations (10 vs. none) than those without COVID (both p = 0.001). No difference between cohorts A and B was observed regarding hospitalization or length of stay. No ICU admission was registered and one patient in cohort B died due to COVID19. Regarding cancer evolution, three patients in cohort A presented progressive disease after COVID19 compared to two in cohort B. One case in cohort B, initially deemed as stable disease, achieved a partial response after COVID19. CONCLUSIONS: Kidney cancer patients who developed COVID19 while on systemic therapy required more treatment interruptions and hospitalizations than those non-infected. However, no significant impact on cancer outcome was observed. Also, no difference was seen between cases on antiangiogenics or immunotherapy.

Quantifying COVID-19's silver lining: Avoided deaths from air quality improvements in Bogotá.

In cities around the world, COVID-19 lockdowns have significantly improved outdoor air quality. Even if only temporary, these improvements could have longer-lasting effects by making chronic air pollution more salient and boosting political pressure for change. To that end, it is important to develop objective estimates of both the air quality improvements associated with lockdowns and the benefits they generate. We use panel data econometric models to estimate the effect of Bogotá's 16-month lockdown on PM2.5 and NO2 pollution, epidemiological models to simulate the effect of reductions in these pollutants on long- and short-term mortality, and benefit transfer methods to value the avoided mortality. We find that on average, Bogotá's lockdown cut PM2.5 pollution by 15% and NO2 pollution by 21%. However, the magnitude of these effects varied considerably over time and across the city's neighborhoods. Equivalent permanent reductions in these pollutants would reduce long-term premature deaths from air pollution by 23% each year, a benefit valued at $1 billion annually. Finally, we estimate that if they occurred ceteris paribus, the temporary reductions in pollutant concentrations in 2020-2021 due to Bogotá's lockdown would have cut short-term deaths from air pollution by 19%, a benefit valued at $244 million.

SARS-CoV-2 infection in patients with melanoma: results of the Spanish Melanoma Group registry.

BACKGROUND: The Spanish Melanoma Group (GEM) developed a national registry of patients with melanoma infected by SARS-CoV-2 ("GRAVID"). METHODS: The main objective was to describe the COVID-19 fatality rate in patients with melanoma throughout the pandemic, as well as to explore the effect of melanoma treatment and tumor stage on the risk of COVID-19 complications. These are the final data of the register, including cases from February 2020 to September 2021. RESULTS: One hundred-fifty cases were registered. Median age was 68 years (range 6-95), 61 (40%) patients were females, and 63 (42%) patients had stage IV. Thirty-nine (26%) were on treatment with immunotherapy, and 17 (11%) with BRAF-MEK inhibitors. COVID-19 was resolved in 119 cases, including 85 (57%) patients cured, 15 (10%) that died due to melanoma, and 20 (13%) that died due to COVID-19. Only age over 60 years, cardiovascular disorders, and diabetes mellitus increased the risk of death due to COVID-19, but not advanced melanoma stage nor melanoma systemic therapies. Three waves have been covered by the register: February-May 2020, August-November 2020, and December 2020-April 2021. The first wave had the highest number of registered cases and COVID-19 mortality. CONCLUSION: Tumor stage or melanoma treatments are non-significant prognostic factors for COVID-19 mortality. During the pandemic in Spain there was a downward trend in the number of patients registered across the waves, as well as in the severity of the infection. GOV IDENTIFIER: NCT04344002.

Clinical-epidemiologic variation in patients treated in the first and second wave of COVID-19 in Lambayeque, Peru: A cluster analysis.

OBJECTIVES: To identify differences in the clinical and epidemiologic characteristics of patients during the first and second waves of the COVID-19 pandemic at the EsSalud Lambayeque health care network, Peru. METHODS: An analytical cross-sectional study of 53,912 patients enrolled during the first and second waves of COVID-19 was conducted. Cluster analysis based on clustering large applications (CLARA) was applied to clinical-epidemiologic data presented at the time of care. The two pandemic waves were compared using clinical-epidemiologic data from epidemiologic surveillance. RESULTS: Cluster analysis identified four COVID-19 groups with a characteristic pattern. Cluster 1 included the largest number of participants in both waves, and the participants were predominantly female. Cluster 2 included patients with gastrointestinal, respiratory, and systemic symptoms. Cluster 3 was the "severe" cluster, characterized by older adults and patients with dyspnea or comorbidities (cardiovascular, diabetes, obesity). Cluster 4 included asymptomatic, pregnant, and less severe patients. We found differences in all clinical-epidemiologic characteristics according to the cluster to which they belonged. CONCLUSION: Using cluster analysis, we identified characteristic patterns in each group. Respiratory, gastrointestinal, dyspnea, anosmia, and ageusia symptoms were higher in the second COVID-19 wave than the first COVID-19 wave.

The angiotensin-(1-7)/Mas receptor axis protects from endothelial cell senescence via klotho and Nrf2 activation.

Endothelial cell senescence is a hallmark of vascular aging that predisposes to vascular disease. We aimed to explore the capacity of the renin-angiotensin system (RAS) heptapeptide angiotensin (Ang)-(1-7) to counteract human endothelial cell senescence and to identify intracellular pathways mediating its potential protective action. In human umbilical vein endothelial cell (HUVEC) cultures, Ang II promoted cell senescence, as revealed by the enhancement in senescence-associated galactosidase (SA-ß-gal+) positive staining, total and telomeric DNA damage, adhesion molecule expression, and human mononuclear adhesion to HUVEC monolayers. By activating the G protein-coupled receptor Mas, Ang-(1-7) inhibited the pro-senescence action of Ang II, but also of a non-RAS stressor such as the cytokine IL-1ß. Moreover, Ang-(1-7) enhanced endothelial klotho levels, while klotho silencing resulted in the loss of the anti-senescence action of the heptapeptide. Indeed, both Ang-(1-7) and recombinant klotho activated the cytoprotective Nrf2/heme oxygenase-1 (HO-1) pathway. The HO-1 inhibitor tin protoporphyrin IX prevented the anti-senescence action evoked by Ang-(1-7) or recombinant klotho. Overall, the present study identifies Ang-(1-7) as an anti-senescence peptide displaying its protective action beyond the RAS by consecutively activating klotho and Nrf2/HO-1. Ang-(1-7) mimetic drugs may thus prove useful to prevent endothelial cell senescence and its related vascular complications.

[The population's perceptions of generic drugs compared to original brand-name drugs in Peruvian hospitals]. / Percepción de la población con respecto a medicamentos genéricos frente a los de marca en hospitales del Perú.

The study aimed to investigate the population's perceptions of generic drugs compared to original brand-name drugs in Peruvian hospitals. Participation included 4,914 persons 18 years and older in 13 cities in Peru, categorized as Lima, large cities, and small cities. The study explored socioeconomic and demographic characteristics and perceptions of generics in comparison to brand-name drugs. In determining the associations for each intersection of variables, the authors calculated the prevalence ratios (PR) and 95% confidence intervals (95%CI), using crude and adjusted Poisson regression with robust variance with Stata 14.0. Of the 4,914 participants, 46.7% felt that generics are less effective than brand-name drugs and 49.3% had recommended or would recommend generics to other people; multivariate analysis showed that individuals with income less than PEN 1,000 (USD 300) were prone to recommending a generic drug (PR = 1.36; 95%CI: 1.14-1.63). The results indicate that the Peruvian population still has mistaken concepts and low acceptance of generic drugs, and the study should serve to develop health policies that ensure low cost and quality when choosing medicines.

El objetivo del estudio fue conocer la percepción de la población con respecto a medicamentos genéricos, frente a los medicamentos de marca, en hospitales del Perú. Participaron del estudio 4.914 personas mayores de 18 años, de 13 ciudades del Perú; clasificándolas en Lima, grandes y pequeñas ciudades. Se exploraron características socioeconómicas, demográficas y de percepción de medicamentos genéricos, en comparación con los medicamentos de marca. Determinando las asociaciones para cada cruce de variables, se calcularon razones de prevalencias (RP) y sus intervalos del 95% de confianza (IC95%), usando regresiones de Poisson crudas y ajustadas con varianza robusta con Stata 14.0. De los 4.914 participantes, el 46,7% estaban de acuerdo con que los medicamentos genéricos son menos eficaces que los medicamentos de marca, el 49,3% ha recomendado o recomendaría a otras personas el uso de medicamentos genéricos, además, el análisis multivariado encontró que las personas que tenían un ingreso económico menor a PEN 1.000 estaban predispuestas a recomendar un medicamento genérico (RP = 1,36; IC95%: 1,14-1,63). Los resultados ponen en manifiesto que la población peruana aún tiene conceptos equívocos y baja aceptación a los medicamentos genéricos. El presente estudio debería servir para desarrollar políticas de salud, que velen por el bajo costo y calidad a la hora de escoger un medicamento.

O objetivo do estudo foi conhecer a percepção da população a respeito dos medicamentos genéricos frente aos medicamentos de marca em hospitais do Peru. Participaram 4.914 pessoas maiores de 18 anos, de 13 cidades do Peru; foram classificadas em Lima, além de grandes e pequenas cidades. Foram exploradas as características socioeconômicas, demográficas e de percepção de medicamentos genéricos em comparação com os medicamentos de marca. Determinando as associações para cada intersecção de variáveis, foram calculadas as razões de prevalências (RP) e seus intervalos de 95% de confiança (IC95%), usando regressões de Poisson brutas e ajustadas com variância robusta com Stata 14.0. Dos 4.914 participantes, um 46,7% estavam de acordo com que os medicamentos genéricos são menos eficazes do que os medicamentos de marca, um 49,3% tem recomendado o recomendaria a outras pessoas o uso de medicamentos genéricos, além disso, a análise multivariada encontrou que as pessoas que tinham um ingresso econômico menor a PEN 1.000 eram propensas a recomendar um medicamento genérico (RP = 1,36; IC95%: 1,14-1,63). Os resultados manifestam que a população peruana ainda tem conceitos equívocos e baixa aceitação dos medicamentos genéricos, e o presente estudo deveria servir para desenvolver políticas de saúde, que assegurem o baixo custo e a qualidade na hora de escolher um medicamento.

Factores tecnológicos-educativos asociados a problemas fisioergonómicos en estudiantes de medicina

Introducción: Existe evidencia sobre el efecto negativo del uso de tecnologías de información y comunicación en estudiantes, sin embargo, poco se conoce sobre problemas fisioergonómicos secundarios a su uso. Objetivo: Identificar los factores tecnológicos-educativos asociados al reporte de 4 problemas fisioergonómicos en estudiantes de medicina. Métodos: Estudio transversal en estudiantes de medicina de 11 países de Latinoamérica y el Caribe. Se utilizó un cuestionario cuyas variables fueron las características socio-educativas y tecnológicas, así como los problemas fisioergonómicos (dolor de cuello, dolor de espalda, ojo seco/rojo y dolor de cabeza). Resultados: De 11 587 estudiantes, 14,5 % reportó presentar 4 problemas fisioergonómicos. La mayoría reportó dolor de cuello (50 %), dolor de espalda (50,5 %) y dolor de cabeza (53,7 %). Tuvieron mayor frecuencia de presentar estos problemas fisioergonómicos las mujeres (RP= 1,06), quienes estudiaron una carrera previa (RP= 1,19), pertenecer a todos los años de estudios (RP= 1,12-1,20), quienes tenían mayor uso de Internet en horas (RP= 1,01) y aquellos que accedían a Twitter en horas de clases (RP= 1,30). La frecuencia de presentar estos problemas disminuyó en quienes tenían menor edad en años (RP= 0,99), procedían de una universidad privada (RP= 0,81), y quienes pertenecían a cualquier grupo extracurricular (RP= 0,67-0,93). Conclusiones: Los factores tecnológicos-educativos asociados al reporte de 4 problemas fisioergonómicos en estudiantes de medicina son ser mujer, tener carrera previa, pertenecer a todos los años de estudios, horas de uso de internet y el acceso a Twitter durante clases.

Introduction: There is evidence on the negative effect of the use of information and communication technologies on students, however, little is known about physio-ergonomic problems secondary to their use. Objective: To identify the technological-educational factors associated with the report of 4 physio-ergonomic problems in medical students. Methods: Cross-sectional study in medical students from 11 countries in Latin America and the Caribbean. A questionnaire was used whose variables were socio-educational and technological characteristics, as well as physio-ergonomic problems (neck pain, back pain, dry/red eye and headache). Results: Of 11 587 students, 14.5% reported presenting 4 physio-ergonomic problems. Most reported neck pain (50%), back pain (50.5%), and headache (53.7%). Women (PR= 1.06), who studied a previous degree (PR= 1.19), who belonged to all years of studies (PR= 1.12-1.20), who had greater use of the Internet, had a higher frequency (in hours) of presenting these physio-ergonomic problems (PR= 1.01) and those who accessed Twitter during school hours (PR= 1.30). They decreased the frequency of presenting these problems, being younger in years (PR= 0.99), coming from a private university (PR= 0.81), and who belonged to any extracurricular group (PR= 0.67-0.93). Conclusions: The technological-educational factors associated with the report of 4 physio-ergonomic problems in medical students were being a woman, having a previous degree, belonging to all the years of study, hours of Internet use and access to Twitter during classes.

Osteonecrosis of the jaw as an adverse bisphosphonate event: three cases of bone metastatic prostate cancer patients treated with zoledronic acid.

Bisphosphonates offer a significant improvement in the quality of life for cancer patients; these potent inhibitors of bone resorption have been shown to markedly reduce the morbidity frequently resulting from bone metastases. Despite the success of bisphosphonates as therapeutic agents, however, toxicity in the form of osteonecrosis of the jaw (ONJ) is a rare complication whose incidence rate has climbed in recent years. ONJ is defined as an unexpected development of necrotic bone in the oral cavity, and is commonly associated with administration of the bisphosphonates Pamidronate and Zoledronate. Clinical features include local pain, soft-tissue swelling, and/or loose teeth; ONJ is also often correlated with previous dental procedures, such as tooth extractions, during biphosphonate therapy. Although additional risk factors-such as corticosteroids, chemotherapy, radiotherapy, trauma or infection-exhibit etiological associations with ONJ, the real pathobiology has not yet been fully elucidated. Here we report our findings on all 2005 OJN cases presented at our institution resulting from bone metastatic prostate cancer treated with zoledronic acid. The incidence of ONJ is nearly 3% (3 out of 104) in these patients.

[Evaluation of the effect of Lactobacillus rhamnosus probiotic culture added to yogurt over Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes and Salmonella enteritidis populations]. / Evaluación del efecto del cultivo probiótico Lactobacillus rhamnosus adicionado a yogurt natural y con probi6ticos comerciales sobre poblaciones de Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes y Salmonella enteritidis.

The effect of different types of probiotics present in yogurt over known populations of Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes and Salmonella enteritidis was evaluated. The three types of yogurt used were: without added probiotics, with added probiotics (Lactobacillus casei CRL_431 and L. acidophilus CRL_730 CHR HANSEN) and another one with the same probiotics mentioned above and Lactobacillus rhamnosus (LR-35) culture. About 10(9) CFU/ mL of each potentially pathogenic bacteria was added to each type of yogurt tested, and kept in refrigeration at 4 degrees C during its shelf life, about 30 days. Bacterial count was done the initial day and every four days. Results obtained show that there is a difference in the inhibition between yogurts without added probiotics and the commercial yogurt with added probiotics; there is a clear inhibitory effect of the last one over S. aureus, E. coli O157:H7 and Listeria monocytogenes. The yogurt with added probiotics and L. rhamnosus did not show any additional inhibitory effect over the bacteria tested when compared with the yogurt with added probiotics. S. enteritidis could not be evaluated because it was not detectable in any yogurt samples evaluated four days after its inoculation. This study confirms the antagonic effect of probiotic cultures over potentially pathogenic bacteria for human beings and animals that may be present in food. Nevertheless, the use of L. rhamnosus did not produce any additional inhibitory effect.

Circulating tumoral cells lack circadian-rhythm in hospitalized metastasic breast cancer patients.

BACKGROUND: The relationship between breast cancer and circadian rhythm variation has been extensively studied. Increased breast tumorigenesis has been reported in melatonin-suppressed experimental models and in observational studies. OBJECTIVES: Circulating Tumor Cells (CTC) circadian- rhythm may optimize the timing of therapies. This is a prospective experimental study to ascertain the day-time and night-time CTC levels in hospitalized metastasic breast cancer (MBC) patients. MATERIAL AND METHODS: CTC are isolated and enumerated from a 08:00 AM and 08:00 PM blood collections. 23 MBC and 23 healthy volunteers entered the study. 69 samples were collected (23 samples at 08:00 AM and 23 samples at 08:00 PM from MBC; 23 samples from healthy volunteers). Results from two patients were rejected due to sample processing errors. No CTC were isolated from healthy-volunteers. RESULTS AND DISCUSSION: No-differences between daytime and night-time CTC were observed. Therefore, we could not ascertain CTC circadian-rhythm in hospitalized metastasic breast cancer patients.

The Angiotensin-(1-7)/Mas Axis Counteracts Angiotensin II-Dependent and -Independent Pro-inflammatory Signaling in Human Vascular Smooth Muscle Cells.

Background and Aims: Targeting inflammation is nowadays considered as a challenging pharmacological strategy to prevent or delay the development of vascular diseases. Angiotensin-(1-7) is a member of the renin-angiotensin system (RAS) that binds Mas receptors and has gained growing attention in the last years as a regulator of vascular homeostasis. Here, we explored the capacity of Ang-(1-7) to counteract human aortic smooth muscle cell (HASMC) inflammation triggered by RAS-dependent and -independent stimuli, such as Ang II or interleukin (IL)-1ß. Methods and Results: In cultured HASMC, the expression of inducible nitric oxide synthase (iNOS) and the release of nitric oxide were stimulated by both Ang II and IL-1ß, as determined by Western blot and indirect immunofluorescence or the Griess method, respectively. iNOS induction was inhibited by Ang-(1-7) in a concentration-dependent manner. This effect was equally blocked by two different Mas receptor antagonists, A779 and D-Pro7-Ang-(1-7), suggesting the participation of a unique Mas receptor subtype. Using pharmacological inhibitors, the induction of iNOS was proven to rely on the consecutive upstream activation of NADPH oxidase and nuclear factor (NF)-κB. Indeed, Ang-(1-7) markedly inhibited the activation of the NADPH oxidase and subsequently of NF-κB, as determined by lucigenin-derived chemiluminescence and electromobility shift assay, respectively. Conclusion: Ang-(1-7) can act as a counter-regulator of the inflammation of vascular smooth muscle cells triggered by Ang II, but also by other stimuli beyond the RAS. Activating or mimicking the Ang-(1-7)/Mas axis may represent a pharmacological opportunity to attenuate the pro-inflammatory environment that promotes and sustains the development of vascular diseases.

Soluble dipeptidyl peptidase-4 induces microvascular endothelial dysfunction through proteinase-activated receptor-2 and thromboxane A2 release.

BACKGROUND: Dipeptidyl peptidase-4 (DPP4) is a key protein in glucose homeostasis and a pharmacological target in type 2 diabetes mellitus. This study explored whether the novel adipokine soluble DPP4 (sDPP4) can cause endothelial dysfunction, an early marker of impaired vascular reactivity. METHOD: Reactivity was studied in mesenteric arteries from 3-month-old female mice, using a small vessel myograph. Thromboxane A2 (TXA2) release was explored in cultured human coronary artery endothelial cells by enzyme immunoassay. RESULTS: Neither the contractility to noradrenaline nor the endothelium-independent relaxations induced by sodium nitroprusside were modified by sDPP4. However, sDPP4 impaired in a concentration-dependent manner the endothelium-dependent relaxation elicited by acetylcholine. The DPP4 inhibitors K579 and linagliptin prevented the defective relaxation induced by sDPP4, as did the protease-activated receptor 2 (PAR2) inhibitor GB83. Downstream of PAR2, the cyclooxygenase (COX) inhibitor indomethacin, the COX2 inhibitor celecoxib or the thromboxane receptors blocker SQ29548 prevented the deleterious effects of sDPP4. Accordingly, sDPP4 triggered the release of TXA2 by endothelial cells, whereas TXA2 release was prevented by inhibiting DPP4, PAR2 or COX. CONCLUSION: In summary, these findings reveal sDPP4 as a direct mediator of endothelial dysfunction, acting through PAR2 activation and the release of vasoconstrictor prostanoids. By interfering with these actions, DPP4 inhibitors might help preserving endothelial function in the context of cardiometabolic diseases.

Enfermedad por Coronavirus 2019 (COVID-19) en América Latina: Papel de la atención primaria en la preparación y respuesta / Coronavirus disease 2019 (COVID-19) in Latin America: Role of primary care in preparedness and response

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