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1.
Am J Physiol Cell Physiol ; 327(3): C525-C544, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38881421

RESUMO

Sodium-glucose cotransporter 2 inhibitors (SGLT2is), initially developed for type 2 diabetes (T2D) treatment, have demonstrated significant cardiovascular and renal benefits in heart failure (HF) and chronic kidney disease (CKD), irrespective of T2D. This review provides an analysis of the multifaceted mechanisms underlying the cardiorenal benefits of SGLT2i in HF and CKD outside of the T2D context. Eight major aspects of the protective effects of SGLT2i beyond glycemic control are explored: 1) the impact on renal hemodynamics and tubuloglomerular feedback; 2) the natriuretic effects via proximal tubule Na+/H+ exchanger NHE3 inhibition; 3) the modulation of neurohumoral pathways with evidence of attenuated sympathetic activity; 4) the impact on erythropoiesis, not only in the context of local hypoxia but also systemic inflammation and iron regulation; 5) the uricosuria and mitigation of the hyperuricemic environment in cardiorenal syndromes; 6) the multiorgan metabolic reprogramming including the potential induction of a fasting-like state, improvement in glucose and insulin tolerance, and stimulation of lipolysis and ketogenesis; 7) the vascular endothelial growth factor A (VEGF-A) upregulation and angiogenesis, and 8) the direct cardiac effects. The intricate interplay between renal, neurohumoral, metabolic, and cardiac effects underscores the complexity of SGLT2i actions and provides valuable insights into their therapeutic implications for HF and CKD. Furthermore, this review sets the stage for future research to evaluate the individual contributions of these mechanisms in diverse clinical settings.


Assuntos
Insuficiência Cardíaca , Insuficiência Renal Crônica , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/fisiopatologia , Animais , Rim/efeitos dos fármacos , Rim/metabolismo , Trocador 3 de Sódio-Hidrogênio/metabolismo , Trocador 3 de Sódio-Hidrogênio/antagonistas & inibidores
3.
Arch Endocrinol Metab ; 68: e230181, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38788146

RESUMO

Hemangioblastomas associated with von Hippel-Lindau (VHL) disease are frequently multiple and recur during prolonged follow-up. Currently, no systemic treatment is available for these tumors. Recent studies have shown the expression of somatostatin receptors in these types of hemangioblastomas. Notably, increased somatostatin receptor expression in a tumor, as determined by peptide-receptor radionuclide imaging, is a predictive factor of response to treatment with somatostatin analogs and peptide-receptor radionuclide therapy. The aim of this study was to describe the case of a patient with increased expression of somatostatin receptors in a suprasellar hemangioblastoma associated with VHL disease and conduct a literature review on somatostatin receptor expression in patients with VHL-associated hemangioblastomas. We describe herein the case of a 51-year-old man with VHL disease who had a suprasellar hemangioblastoma detected on magnetic resonance imaging. Peptide-receptor radionuclide imaging using gallium-68-DOTATOC (68Ga-DOTATOC) identified increased expression of somatostatin receptors in the suprasellar hemangioblastoma, along with multiple pancreatic neuroendocrine tumors and bilateral pheochromocytomas. The patient was treated for 1 year with lanreotide, a somatostatin analog. A repeat 68Ga-DOTATOC 1 year after starting lanreotide revealed decreased radiotracer uptake by the hemangioblastoma, consistent with a metabolic response. The presence of somatostatin receptors in hemangioblastomas associated with VHL disease is a novel finding. The decreased expression of these receptors after treatment with a somatostatin analog, as described in the present case, positions the somatostatin receptor as a new target for novel diagnostic, therapeutic, and follow-up opportunities in patients with VHL disease.


Assuntos
Hemangioblastoma , Receptores de Somatostatina , Doença de von Hippel-Lindau , Humanos , Hemangioblastoma/diagnóstico por imagem , Doença de von Hippel-Lindau/complicações , Receptores de Somatostatina/análise , Receptores de Somatostatina/metabolismo , Masculino , Pessoa de Meia-Idade , Octreotida/uso terapêutico , Octreotida/análogos & derivados , Neoplasias Cerebelares/diagnóstico por imagem , Neoplasias Cerebelares/tratamento farmacológico , Seguimentos , Imageamento por Ressonância Magnética , Compostos Radiofarmacêuticos/uso terapêutico
4.
Am J Physiol Cell Physiol ; 326(6): C1573-C1589, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557357

RESUMO

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) reduce blood pressure (BP) in patients with hypertension, yet the precise molecular mechanisms remain elusive. SGLT2i inhibits proximal tubule (PT) NHE3-mediated sodium reabsorption in normotensive rodents, yet no hypotensive effect is observed under this scenario. This study examined the effect of empagliflozin (EMPA) on renal tubular sodium transport in normotensive and spontaneously hypertensive rats (SHRs). It also tested the hypothesis that EMPA-mediated PT NHE3 inhibition in normotensive rats is associated with upregulation of distal nephron apical sodium transporters. EMPA administration for 14 days reduced BP in 12-wk-old SHRs but not in age-matched Wistar rats. PT NHE3 activity was inhibited by EMPA treatment in both Wistar and SHRs. In Wistar rats, EMPA increased NCC activity, mRNA expression, protein abundance, and phosphorylation levels, but not in SHRs. SHRs showed higher NKCC2 activity and an abundance of cleaved ENaC α and γ subunits compared with Wistar rats, none of which were affected by EMPA. Another set of male Wistar rats was treated with EMPA, the NCC inhibitor hydrochlorothiazide (HCTZ), and EMPA combined with HCTZ or vehicle for 14 days. In these rats, BP reduction was observed only with combined EMPA and HCTZ treatment, not with either drug alone. These findings suggest that NCC upregulation counteracts EMPA-mediated inhibition of PT NHE3 in male normotensive rats, maintaining their baseline BP. Moreover, the reduction of NHE3 activity without further upregulation of major apical sodium transporters beyond the PT may contribute to the BP-lowering effect of SGLT2i in experimental models and patients with hypertension.NEW & NOTEWORTHY This study suggests that reduced NHE3-mediated sodium reabsorption in the renal proximal tubule may account, at least in part, for the BP-lowering effect of SGLT2 inhibitors in the setting of hypertension. It also demonstrates that chronic treatment with SGLT2 inhibitors upregulates NCC activity, phosphorylation, and expression in the distal tubule of normotensive but not hypertensive rats. SGLT2 inhibitor-mediated upregulation of NCC seems crucial to counteract proximal tubule natriuresis in subjects with normal BP.


Assuntos
Compostos Benzidrílicos , Glucosídeos , Hipertensão , Ratos Endogâmicos SHR , Ratos Wistar , Inibidores do Transportador 2 de Sódio-Glicose , Trocador 3 de Sódio-Hidrogênio , Regulação para Cima , Animais , Masculino , Trocador 3 de Sódio-Hidrogênio/metabolismo , Trocador 3 de Sódio-Hidrogênio/genética , Trocador 3 de Sódio-Hidrogênio/antagonistas & inibidores , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Glucosídeos/farmacologia , Compostos Benzidrílicos/farmacologia , Regulação para Cima/efeitos dos fármacos , Ratos , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Membro 3 da Família 12 de Carreador de Soluto/metabolismo , Membro 3 da Família 12 de Carreador de Soluto/genética , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Rim/metabolismo , Rim/efeitos dos fármacos
5.
Int J Obes (Lond) ; 48(2): 254-262, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37932408

RESUMO

BACKGROUND: Comorbidities such as obesity, hypertension, and diabetes are associated with COVID-19 development and severity, probably due to immune dysregulation; however, the mechanisms underlying these associations are not clear. The immune signatures of hypertensive patients with obesity with COVID-19 may provide new insight into the mechanisms of immune dysregulation and progression to severe disease in these patients. METHODS: Hypertensive patients were selected prospectively from a multicenter registry of adults hospitalized with COVID-19 and stratified according to obesity (BMI ≥ 30 kg/m²). Clinical data including baseline characteristics, complications, treatment, and 46 immune markers were compared between groups. Logistic regression was performed to identify variables associated with the risk of COVID-19 progression in each group. RESULTS: The sample comprised 213 patients (89 with and 124 without obesity). The clinical profiles of patients with and without obesity differed, suggesting potential interactions with COVID-19 severity. Relative to patients without obesity, patients with obesity were younger and fewer had cardiac disease and myocardial injury. Patients with obesity had higher EGF, GCSF, GMCSF, interleukin (IL)-1ra, IL-5, IL-7, IL-8, IL-15, IL-1ß, MCP 1, and VEGF levels, total lymphocyte counts, and CD8+ CD38+ mean fluorescence intensity (MFI), and lower NK-NKG2A MFI and percentage of CD8+ CD38+ T cells. Significant correlations between cytokine and immune cell expression were observed in both groups. Five variables best predicted progression to severe COVID-19 in patients with obesity: diabetes, the EGF, IL-10, and IL-13 levels, and the percentage of CD8+ HLA-DR+ CD38+ cells. Three variables were predictive for patients without obesity: myocardial injury and the percentages of B lymphocytes and HLA-DR+ CD38+ cells. CONCLUSION: Our findings suggest that clinical and immune variables and obesity interact synergistically to increase the COVID-19 progression risk. The immune signatures of hypertensive patients with and without obesity severe COVID-19 highlight differences in immune dysregulation mechanisms, with potential therapeutic applications.


Assuntos
COVID-19 , Diabetes Mellitus , Hipertensão , Adulto , Humanos , Linfócitos T CD8-Positivos , COVID-19/complicações , COVID-19/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Fator A de Crescimento do Endotélio Vascular , Antígenos HLA-DR/metabolismo , Hipertensão/complicações , Hipertensão/epidemiologia , Hipertensão/metabolismo , Obesidade/complicações , Obesidade/metabolismo
6.
Arch. endocrinol. metab. (Online) ; 68: e230181, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1556948

RESUMO

SUMMARY Hemangioblastomas associated with von Hippel-Lindau (VHL) disease are frequently multiple and recur during prolonged follow-up. Currently, no systemic treatment is available for these tumors. Recent studies have shown the expression of somatostatin receptors in these types of hemangioblastomas. Notably, increased somatostatin receptor expression in a tumor, as determined by peptide-receptor radionuclide imaging, is a predictive factor of response to treatment with somatostatin analogs and peptide-receptor radionuclide therapy. The aim of this study was to describe the case of a patient with increased expression of somatostatin receptors in a suprasellar hemangioblastoma associated with VHL disease and conduct a literature review on somatostatin receptor expression in patients with VHL-associated hemangioblastomas. We describe herein the case of a 51-year-old man with VHL disease who had a suprasellar hemangioblastoma detected on magnetic resonance imaging. Peptide-receptor radionuclide imaging using gallium-68-DOTATOC (68Ga-DOTATOC) identified increased expression of somatostatin receptors in the suprasellar hemangioblastoma, along with multiple pancreatic neuroendocrine tumors and bilateral pheochromocytomas. The patient was treated for 1 year with lanreotide, a somatostatin analog. A repeat 68Ga-DOTATOC 1 year after starting lanreotide revealed decreased radiotracer uptake by the hemangioblastoma, consistent with a metabolic response. The presence of somatostatin receptors in hemangioblastomas associated with VHL disease is a novel finding. The decreased expression of these receptors after treatment with a somatostatin analog, as described in the present case, positions the somatostatin receptor as a new target for novel diagnostic, therapeutic, and follow-up opportunities in patients with VHL disease.

7.
Radiol Bras ; 56(4): 171-178, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37829589

RESUMO

Objective: To evaluate the accuracy of preoperative positron emission tomography/computed tomography with 68Ga-labeled prostate-specific membrane antigen (68Ga-PSMA PET/CT) for staging prostate cancer and compare it with magnetic resonance imaging (MRI) using histopathology of surgical specimens as the gold standard. Materials and Methods: In this retrospective study, 65 patients with prostate cancer were analyzed. Results: The accuracy of 68Ga-PSMA PET/CT for tumor detection was 95%, and that of MRI was 91%. There was no difference between 68Ga-PSMA PET/CT and MRI regarding localization of the lesion. The sensitivity of 68Ga-PSMA PET/CT for detecting extraprostatic extension was quite low (14%). For detection of seminal vesicle invasion, 68Ga-PSMA PET/CT showed a sensitivity of 57% and accuracy of 91%. There was a moderate correlation between the maximum standardized uptake value (SUVmax) and the serum level of prostate-specific antigen (p < 0.01; ρ = 0.368) and between the SUVmax and the International Society of Urological Pathology (ISUP) grade (p < 0.01; ρ = 0.513). Conclusion: 68Ga-PSMA PET/CT is a promising tool for detecting and evaluating the primary tumor, which can alter the staging and management of the disease.


Objetivo: Avaliar a acurácia da tomografia por emissão de pósitrons/tomografia computadorizada com PSMA (PET-PMSA) pré-operatória para estadiamento do câncer de próstata e compará-la com a ressonância magnética (RM) utilizando o histopatológico cirúrgico como padrão ouro. Materiais e Métodos: Neste estudo retrospectivo foram analisados 65 pacientes com câncer de próstata. Resultados: A acurácia da PET-PSMA para a detecção tumoral foi de 95% e a da RM foi de 91%. Não houve diferença entre a PET-PSMA e a RM quanto à localização da lesão. A PET-PSMA apresentou baixa sensibilidade (14%) para detecção de extensão extraprostática em comparação ao histopatológico. Para detecção de invasão de vesícula seminal, a PET-PSMA apresentou sensibilidade de 57% e acurácia de 91% em comparação ao histopatológico. Houve correlação moderada entre o SUVmax e o PSA (p < 0,01; ρ = 0,368) e entre o SUVmax e o ISUP (p < 0,01; ρ = 0,513). Conclusão: A PET-PSMA é uma ferramenta promissora para detecção e avaliação do tumor primário, alterando o estadiamento e a conduta do paciente.

8.
J Nucl Cardiol ; 30(6): 2702-2711, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37605061

RESUMO

BACKGROUND: Chagas heart disease (CHD) is characterized by progressive myocardial inflammation associated with myocardial fibrosis and segmental abnormalities that may lead to malignant ventricular arrhythmia and sudden cardiac death. This arrhythmia might be related to the persistence of parasitemia or inflammation in the myocardium in late-stage CHD. Positron emission tomography/computed tomography (PET/CT) has been used to detect myocardial inflammation in non-ischemic cardiomyopathies, such as sarcoidosis, and might be useful for risk prediction in patients with CHD. METHODS AND RESULTS: Twenty-four outpatients with chronic CHD were enrolled in this prospective cross-sectional study between May 2019 and March 2022. The patients were divided into two groups: those with sustained ventricular tachycardia and/or aborted sudden cardiac death who required implantable cardioverter-defibrillators, and those with the same stages of CHD and no complex ventricular arrhythmia. Patients underwent 18F-fluorodeoxyglucose (18F-FDG) and 68Ga-DOTATOC PET/CT, and blood samples were collected for qualitative parasite assessment by polymerase chain reaction. Although similar proportions of patients with and without complex ventricular arrhythmia showed 18F-FDG and 68Ga-DOTATOC uptake, 68Ga-DOTATOC corrected SUVmax was higher in patients with complex arrhythmia (3.4 vs 1.7; P = .046), suggesting that inflammation could be associated with the presence of malignant arrhythmia in the late stages of CHD. We also detected Trypanosoma cruzi in both groups, with a nonsignificant trend of increased parasitemia in the group with malignant arrhythmia (66.7% vs 33.3%). CONCLUSION: 18F-FDG and 68Ga-DOTATOC uptake on PET/CT may be useful for the detection of myocardial inflammation in patients with Chagas cardiomyopathy, and 68Ga-DOTATOC uptake may be associated with the presence of malignant arrhythmia, with potential therapeutic implications.


Assuntos
Doença de Chagas , Cardiopatias , Miocardite , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodos , Radioisótopos de Gálio , Estudos Transversais , Parasitemia , Estudos Prospectivos , Miocardite/diagnóstico por imagem , Arritmias Cardíacas/diagnóstico por imagem , Inflamação/diagnóstico por imagem , Morte Súbita Cardíaca , Doença de Chagas/complicações , Doença de Chagas/diagnóstico por imagem
10.
BMC Public Health ; 23(1): 1424, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491194

RESUMO

BACKGROUND: The presence of food insecurity in households headed by older people is related to social inequalities. The objective of this study was to analyze the prevalence and factors associated with moderate/severe food insecurity in households headed by older people. METHODS: A cross-sectional study based on a nationally representative sample of older adults aged ≥ 60 years was conducted using data from the 2017/2018 Family Budget Survey. In the study, moderate/severe food insecurity was the dependent variable, with food insecurity assessed with the Brazilian Household Food Insecurity Measurement Scale. Prevalence and odds ratio estimates were generated with 99% confidence intervals. Data analysis was performed using STATA software. FINDINGS: A total of 16,314 households headed by older people were identified. Approximately 10.1% of these households were in the moderate/severe range for food insecurity. The majority are female (11.9%)and self-declared indigenous people (25.5%), with a lack of schooling (18.3%) and a per capita income of up to half of one minimum wage (29.6%). The analysis model found that color/race, region, schooling, per capita household income, and social benefits received in the household were statistically significant factors (p value < 0.01). CONCLUSION: Moderate/severe food insecurity in households headed by older people is associated with the pronounced social inequalities present in Brazil, and these findings intensify the need for additional study of the challenges faced by this age group.


Assuntos
Características da Família , Abastecimento de Alimentos , Humanos , Masculino , Feminino , Idoso , Estudos Transversais , Brasil/epidemiologia , Fatores Socioeconômicos , Inquéritos e Questionários , Insegurança Alimentar
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