Adipose Tissue Metabolic Changes In Chronic Kidney Disease

Adipose tissue is a complex organ whose functions go beyond being an energy reservoir to sustain proper body energy homeostasis. Functioning as an endocrine organ, the adipose tissue has an active role in the body\u27s metabolic balance regulation through several secreted factors generally termed as adipokines. Thus, adipose tissue dysregulation in chronic kidney disease (CKD) can have a deep impact in the pathophysiology of diseases associated with metabolic dysregulation including metabolic syndrome, insulin resistance (IR), atherosclerosis, and even cachexia. CKD is a progressive disorder linked to increased morbidity and mortality. Despite being characterized by renal function loss, CKD is accompanied by metabolic disturbances such as dyslipidemia, protein energy wasting, chronic low-grade inflammation, IR, and lipid redistribution. Thus far, the mechanisms by which these changes occur and the role of adipose tissue in CKD development and progression are unclear. Further understanding of how these factors develop could have implications for the management of CKD by helping identify pharmacological targets to improve CKD outcomes

Sphaerococcus coronopifolius bromoterpenes as potential cancer stem celltargeting agents

Cancer is one of the major threats to human health and, due to distinct factors, it is expected that its incidence will increase in the next decades leading to an urgent need of new anticancer drugs development. Ongoing experimental and clinical observations propose that cancer cells with stem-like properties (CSCs) are involved on the development of lung cancer chemoresistance. As tumour growth and metastasis can be controlled by tumourassociated stromal cells, the main goal of this study was to access the antitumor potential of five bromoterpenes isolated from Sphaerococcus coronopifolius red alga to target CSCs originated in a co-culture system of fibroblast and lung malignant cells. Cytotoxicity of compounds (10–500 μM; 72 h) was evaluated on monocultures of several malignant and non-malignant cells lines (HBF, BEAS-2B, RenG2, SC-DRenG2) and the effects estimated by MTT assay. Co-cultures of non-malignant human bronchial fibroblasts (HBF) and malignant human bronchial epithelial cells (RenG2) were implemented and the compounds ability to selectively kill CSCs was evaluated by sphere forming assay. The interleucine-6 (IL-6) levels were also determined as cytokine is crucial for CSCs. Regarding the monocultures results bromosphaerol selectively eliminated the malignant cells. Both 12S-hydroxy-bromosphaerol and 12R-hydroxy-bromosphaerol steroisomers were cytotoxic towards non-malignant bronchial BEAS-2B cell line, IC50 of 4.29 and 4.30 μM respectively. However, none of the steroisomers induced damage in the HBFs. As to the co-cultures, 12R-hydroxy-bromosphaerol revealed the highest cytotoxicity and ability to abrogate the malignant stem cells; however its effects were IL-6 independent. The results presented here are the first evidence of the potential of these bromoterpenes to abrogate CSCs opening new research opportunities. The 12R-hydroxy-bromosphaerol revealed to be the most promising compound to be test in more complex living models.info:eu-repo/semantics/publishedVersio

Macrophage and adipocyte interaction as a source of inflammation in kidney disease

In obesity, adipose tissue derived inflammation is associated with unfavorable metabolic consequences. Uremic inflammation is prevalent and contributes to detrimental outcomes. However, the contribution of adipose tissue inflammation in uremia has not been characterized. We studied the contribution of adipose tissue to uremic inflammation in-vitro, in-vivo and in human samples. Exposure to uremic serum resulted in activation of inflammatory pathways including NFκB and HIF1, upregulation of inflammatory cytokines/chemokines and catabolism with lipolysis, and lactate production. Also, co-culture of adipocytes with macrophages primed by uremic serum resulted in higher inflammatory cytokine expression than adipocytes exposed only to uremic serum. Adipose tissue of end stage renal disease subjects revealed increased macrophage infiltration compared to controls after BMI stratification. Similarly, mice with kidney disease recapitulated the inflammatory state observed in uremic patients and additionally demonstrated increased peripheral monocytes and inflammatory polarization of adipose tissue macrophages (ATMS). In contrast, adipose tissue in uremic IL-6 knock out mice showed reduced ATMS density compared to uremic wild-type controls. Differences in ATMS density highlight the necessary role of IL-6 in macrophage infiltration in uremia. Uremia promotes changes in adipocytes and macrophages enhancing production of inflammatory cytokines. We demonstrate an interaction between uremic activated macrophages and adipose tissue that augments inflammation in uremia

Risk factors for infection, predictors of severe disease, and antibody response to COVID-19 in patients with inflammatory rheumatic diseases in Portugal: a multicenter, nationwide study

Copyright © 2022 Cruz-Machado, Barreira, Bandeira, Veldhoen, Gomes, Serrano, Duarte, Rato, Miguel Fernandes, Garcia, Pinheiro, Bernardes, Madeira, Miguel, Torres, Bento Silva, Pestana, Almeida, Mazeda, Cunha Santos, Pinto, Sousa, Parente, Sequeira, Santos, Fonseca and Romão. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Objective: To identify risk factors for SARS-CoV-2 infection and for severe/critical COVID-19, and to assess the humoral response after COVID-19 in these patients. Methods: Nationwide study of adult patients with inflammatory RMDs prospectively followed in the Rheumatic Diseases Portuguese Register-Reuma.pt-during the first 6 months of the pandemic. We compared patients with COVID-19 with those who did not develop the disease and patients with mild/moderate disease with those exhibiting severe/critical COVID-19. IgG antibodies against SARS-CoV-2 were measured ≥3 months after infection and results were compared with matched controls. Results: 162 cases of COVID-19 were registered in a total of 6,363 appointments. Patients treated with TNF inhibitors (TNFi; OR = 0.160, 95% CI 0.099-0.260, P < 0.001) and tocilizumab (OR 0.147, 95% CI 0.053-0.408, P < 0.001) had reduced odds of infection. Further, TNFi tended to be protective of severe and critical disease. Older age, major comorbidities, and rituximab were associated with an increased risk of infection and worse prognosis. Most patients with inflammatory RMDs (86.2%) developed a robust antibody response. Seroconversion was associated with symptomatic disease (OR 13.46, 95% CI 2.21-81.85, P = 0.005) and tended to be blunted by TNFi (OR 0.17, 95% CI 0.03-1.05; P = 0.057). Conclusions: TNFi and tocilizumab reduced the risk of infection by SARS-CoV-2. Treatment with TNFi also tended to reduce rates of severe disease and seroconversion. Older age, general comorbidities and rituximab were associated with increased risk for infection and worse prognosis, in line with previous reports. Most patients with RMDs developed a proper antibody response after COVID-19, particularly if they had symptomatic disease.We acknowledge the generous sharing of the expression constructs by Dr. Florian Krammer, Icahn School of Medicine at Mount Sinai, New York, USA [Development of SARS-CoV-2 reagents was partially supported by the NIAID Centers of Excellence for Influenza Research and Surveillance (CEIRS) contract HHSN272201400008C] and the protein production by Drs. Paula Alves and Rute Castro at Instituto de Biologia Experimental e Tecnológica (iBET) Oeiras, Portugal as part of the Serology COVID consortium.info:eu-repo/semantics/publishedVersio

Tracking of the intracellular cytokines’ transduced signals

SERRANO, Eurico da Silva - Tracking of the intracellular cytokines’ transduced signals. Coimbra : [s.n.], 2016. Dissertação de Mestrado.Cancer stem cells (CSCs) are cancer cells that display stem-like properties and that are deeply involved in several steps of the carcinogenic progression. They are able to drive tumorigenesis and differentiation, thus explaining tumor heterogeneity, and are responsible for tumor relapse after treatment due to their high resistance to the common therapeutic approaches. Their origin is still controversial, but evidence from targeted therapy assays showed that although this population of cells may be diminished, it is able to be replenished by dedifferentiation of terminally differentiated tumor cells. The mechanisms underlying the dedifferentiation process are still unclear, but a pivotal role for the tumor microenvironment (TME) and its derived soluble factors has been proposed. In agreement, our group has previously found that interleukin 6 (IL-6), Activin-A and Granulocyte colony-stimulating factor (G-CSF) are able to drive malignant human bronchial epithelial cells’ dedifferentiation. The present study aimed to identify the intracellular signaling pathways activated during the abovementioned cytokine-driven dedifferentiation process. To this end IL-6, G-CSF and Activin-A intracellular signaling pathways were differentially blocked in Transwell® co-cultures of RenG2 cells and E2a fibroblasts, so their individual role in the RenG2 cells’ dedifferentiation process was ascertained. Finally, by implementing the system in the presence of exosome-mediated communication blockers, the role of these vesicles in the intercellular communication process was assessed. The attained results suggested that IL-6 and Activin-A were the main orchestrators of the dedifferentiation process since the presence of at least one of these cytokines led to the development of a stem cell-like population inside the RenG2 cells. Additionally, Activin-A seemed to act as a sensor of the CSCs’ pool homeostasis. G-CSF, per si, was excluded as a driver of dedifferentiation but a role for this cytokine in the maintenance of the undifferentiated phenotype was suggested.Células estaminais tumorais (CETs) são células cancerígenas que exibem propriedades estaminais e que estão altamente envolvidas nos vários passos da progressão tumoral. Estas células são capazes de regular a tumorigenicidade e a diferenciação tumoral, explicando-se deste modo a diversidade celular encontrada nos tumores. Por outro lado, são ainda responsáveis pelas recidivas após tratamento devido ao seu elevado grau de resistência às terapias convencionais. A origem das CETs é ainda alvo de controvérsia, mas estudos recentes mostraram que quando as CETs são eliminadas por terapias direcionadas, a sua população pode ser regenerada por dediferenciação de células tumorais diferenciadas. Contudo, os mecanismos que medeiam esta dediferenciação não são ainda claros. Resultados prévios do nosso laboratório identificaram a Interleucina-6 (IL6), a Activina-A e o Factor estimulador de colónias derivado de granulócitos (GCSF) como mediadores do processo de diferenciação de uma linha maligna de epitélio bronquial humano. Neste sentido, o presente estudo teve por objetivo identificar o mecanismo subjacente ao processo de dediferenciação conduzido pelas citocinas supracitadas. Para isso as vias de sinalização intercelular da IL6, do G-CSF e da Activin-A foram diferencialmente bloqueadas com vista a permitir o estabelecimento do papel individual de cada citocina no processo de dediferenciação. Finalmente, a realização das mesmas experiências na presença de inibidores da comunicação mediada por exosomas permitiu avaliar o envolvimento destas vesículas no mesmo processo. Os resultados obtidos sugerem que a IL-6 e a Activina-A são os principais responsáveis pelo processo de dediferenciação, já que a presença de apenas uma delas leva à aquisição de fenótipo estaminal pelas células RenG2. Por outro lado, foi também possível deduzir que a Activina-A funciona como um sensor da homeostase da população de CETs. O G-CSF, por seu turno, foi excluído como mediador efetivo do processo de dediferenciação, mas parece desempenhar um importante papel na manutenção das características estaminais das CETs

Uremic Myopathy and Mitochondrial Dysfunction in Kidney Disease

Alterations in muscle structure and function in chronic kidney disease (CKD) patients are associated with poor outcomes. As key organelles in muscle cell homeostasis, mitochondrial metabolism has been studied in the context of muscle dysfunction in CKD. We conducted a study to determine the contribution of oxidative metabolism, glycolysis and fatty acid oxidation to the muscle metabolism in CKD. Mice developed CKD by exposure to adenine in the diet. Muscle of CKD mice showed significant weight loss compared to non-CKD mice, but only extensor digitorum longus (EDL) muscle showed a decreased number of fibers. There was no difference in the proportion of the various muscle fibers in CKD and non-CKD mice. Muscle of CKD mice had decreased expression of proteins associated with oxidative phosphorylation but increased expression of enzymes and transporters associated with glycolysis. In cell culture, myotubes exposed to uremic serum demonstrated decreased oxygen consumption rates (OCR) when glucose was used as substrate, conserved OCR when fatty acids were used and increased lactate production. In conclusion, mice with adenine-induced CKD developed sarcopenia and with increased glycolytic metabolism but without gross changes in fiber structure. In vitro models of uremic myopathy suggest fatty acid utilization is preserved compared to decreased glucose utilization

Sphaerococcus coronopifolius bromoterpenes as potential cancer stem cell-targeting agents

Cancer is one of the major threats to human health and, due to distinct factors, it is expected that its incidence will increase in the next decades leading to an urgent need of new anticancer drugs development. Ongoing experimental and clinical observations propose that cancer cells with stem-like properties (CSCs) are involved on the development of lung cancer chemoresistance. As tumour growth and metastasis can be controlled by tumourassociated stromal cells, the main goal of this study was to access the antitumor potential of five bromoterpenes isolated from Sphaerococcus coronopifolius red alga to target CSCs originated in a co-culture system of fibroblast and lung malignant cells. Cytotoxicity of compounds (10–500 μM; 72 h) was evaluated on monocultures of several malignant and non-malignant cells lines (HBF, BEAS-2B, RenG2, SC-DRenG2) and the effects estimated by MTT assay. Co-cultures of non-malignant human bronchial fibroblasts (HBF) and malignant human bronchial epithelial cells (RenG2) were implemented and the compounds ability to selectively kill CSCs was evaluated by sphere forming assay. The interleucine-6 (IL-6) levels were also determined as cytokine is crucial for CSCs. Regarding the monocultures results bromosphaerol selectively eliminated the malignant cells. Both 12S-hydroxy-bromosphaerol and 12R-hydroxy-bromosphaerol steroisomers were cytotoxic towards non-malignant bronchial BEAS-2B cell line, IC50 of 4.29 and 4.30 μM respectively. However, none of the steroisomers induced damage in the HBFs. As to the co-cultures, 12R-hydroxy-bromosphaerol revealed the highest cytotoxicity and ability to abrogate the malignant stem cells; however its effects were IL-6 independent. The results presented here are the first evidence of the potential of these bromoterpenes to abrogate CSCs opening new research opportunities. The 12R-hydroxy-bromosphaerol revealed to be the most promising compound to be test in more complex living models.info:eu-repo/semantics/publishedVersio

Stroma-derived IL-6, G-CSF and Activin-A mediated dedifferentiation of lung carcinoma cells into cancer stem cells

Cancer stem cells (CSCs) are a small population of resistant cells inhabiting the tumors. Although comprising only nearly 3% of the tumor mass, these cells were demonstrated to orchestrate tumorigenesis and differentiation, underlie tumors' heterogeneity and mediate therapy resistance and tumor relapse. Here we show that CSCs may be formed by dedifferentiation of terminally differentiated tumor cells under stress conditions. Using a elegant co-culture cellular system, we were able to prove that nutrients and oxygen deprivation activated non-malignant stromal fibroblasts, which in turn established with tumor cells a paracrine loop mediated by Interleukine-6 (IL-6), Activin-A and Granulocyte colony-stimulating factor (G-CSF), that drove subsequent tumor formation and cellular dedifferentiation. However, by scavenging these cytokines from the media and/or blocking exosomes' mediated communication it was possible to abrogate dedifferentiation thus turning these mechanisms into potential therapeutic targets against cancer progression