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Association of Aquaporin-3, Aquaporin-7, NOS3 and CYBA polymorphisms with hypertensive disorders in women

Publication . da Silva, Inês Vieira; Santos, Ana Carolina; Matos, Andreia; Silva, Alda Pereira da; Soveral, Graça; Rebelo, Irene; Bicho, Manuel

Preeclampsia (PE), a pregnancy disorder influenced by oxidative stress and hypoxia, affects the health of the mother and baby and is associated with an increased risk of future hypertension (HT). Aquaporins are a family of water channels, comprising members that also transport glycerol (aquaglyceroporins) and hydrogen peroxide (peroxiporins), key molecules for metabolic homeostasis and redox signaling. Here, we investigated the association of Aquaporin-3 (AQP3; rs2231231), Aquaporin-7 (AQP7; rs2989924), NOS3 (4B/A intron) and CYBA (rs4673) genetic polymorphisms with the development of hypertensive disorders by qPCR/PCR in a cohort of 150 normotensive (NT) women (N = 90) or with previous PE (N = 60) during pregnancy. Prospectively, women were reclassified 2-16 years after pregnancy as NT (N = 98) or hypertensive (N = 48) and the genetic associations were reevaluated. In addition, genetic associations were reevaluated and compared between normotensive and hypertensive (HT) subjects. We found that AQP3 rs2231231, an aquaglyceroporin/peroxiporin, is associated with the development of HT, whereas AQP7, NOS3 and CYBA polymorphism did not correlate with PE or future HT. Because AQP3 was associated with hypertension only after pregnancy, its role might be related to later risk factors of hypertension such as metabolic syndrome or oxidative stress.

2021-02-23Journal article

Restricted access

Glutamine and cystine-enriched diets modulate aquaporins gene expression in the small intestine of piglets

Publication . da Silva, Inês V.; Soares, Bárbara P.; Pimpão, Catarina; Pinto, Rui M. A.; Costa, Teresa; Freire, João P. B.; Corrent, Etienne; Chalvon-Demersay, Tristan; Prates, José A.M; Lopes, Paula A.; Soveral, Graça

ABSTRACT - The regulation of glycerol permeability in the gastrointestinal tract is crucial to control fat deposition, lipolysis and gluconeogenesis. Knowing that the amino acid glutamine is a physiological regulator of gluconeogenesis, whereas cystine promotes adiposity, herein we investigated the effects of dietary supplementation with glutamine and cystine on the serum biochemical parameters of piglets fed on amino acid-enriched diets, as well as on the transcriptional profile of membrane water and glycerol channels aquaporins (AQPs) in the ileum portion of the small intestine and its impact on intestinal permeability. Twenty male piglets with an initial body weight of 8.8 ± 0.89 kg were allocated to four dietary treatments (n = 5) and received, during a four week-period, a basal diet without supplementation (control) or supplemented with 8 kg/ton of glutamine (Gln), cystine (Cys) or the combination of the two amino acids in equal proportions (Gln + Cys). Most biochemical parameters were found improved in piglets fed Gln and Cys diet. mRNA levels of AQP3 were found predominant over the others. Both amino acids, individually or combined, were responsible for a consistent downregulation of AQP1, AQP7 and AQP10, without impacting on water permeability. Conversely, Cys enriched diet upregulated AQP3 enhancing basolateral membranes glycerol permeability and downregulating glycerol kinase (GK) of intestinal cells. Altogether, our data reveal that amino acids dietary supplementation can modulate intestinal AQPs expression and unveil AQP3 as a promising target for adipogenesis regulation.

2021-01-19Journal article

Open access

Cancer chemotherapeutic agents using a nanotechnological approach

Publication . Pinho, Jacinta O.; Gaspar, Maria Manuela; Soveral, Graça; Casini, Angela

The complexity and aggressiveness of cancer, as well as its increasing incidence and mortality worldwide, prompts the search for novel and alternative therapeutic strategies with improved effectiveness and safety. In this sense, the identification of therapeutic targets, the discovery of new molecules with antitumor potential, and the design of drug delivery systems create opportunities for a successful cancer management. Among compounds with promising anticancer activity are metal-based complexes and hybrid molecules, with some already approved for clinical use and others undergoing clinical trials or in preclinical research. In the present work, two compounds with promising anticancer potential were studied, the Cu2+ complex Cuphen [Cu(phen)Cl2] and a dual acting hybrid molecule, HM, containing two moieties – a DNA alkylating triazene and a ʟ-tyrosine analogue, 4-S-CAP, with high specificity for tyrosinase. Cuphen may act through the modulation of aquaporins (AQPs), inhibiting AQP3-mediated glycerol transport and affecting cell migration. In turn, the dual acting HM demonstrated a superior antiproliferative activity compared to the clinically approved temozolomide. Also, HM significantly inhibited tyrosinase activity and arrested cell cycle in G0/G1 phase. Following these promising in vitro results, the next goal was to maximize the in vivo therapeutic efficacy of these compounds by exploring the versatility of the most successful lipid-based nanosystem, liposomes. Long circulating liposomal formulations, with suitable physicochemical properties for each molecule, were designed and evaluated in preclinical studies. In the case of Cuphen, liposomes with pH-sensitive properties were designed to promote a locally-triggered release at the slightly acidic tumor microenvironment. In vivo, liposomal Cuphen significantly reduced melanoma and colon cancer progression, compared to free form. Furthermore, Cuphen liposomes displaying magnetic properties were successfully developed for further increase their accumulation at tumor sites upon application of an external magnetic field. For HM, an efficient incorporation in long circulating liposomes was obtained. In a subcutaneous murine melanoma model, liposomal HM remarkably reduced tumor progression, compared to free HM. Moreover, in a syngeneic metastatic melanoma model, a reduction on the number of lung metastases was observed for liposomal HM compared to all groups, including the positive control temozolomide. Remarkably, in the subcutaneous melanoma model, biodistribution studies of LIP HM showed that, 48 h post-administration, 4% of the injected dose per gram of tumor was attained, correlating with the obtained therapeutic activity. Importantly, all developed nanoformulations, for both anticancer compounds, demonstrated to be safe for parenteral administration, in healthy animals, not eliciting hepatic toxic side effects neither hemolytic activity. Furthermore, the long-term stability of liposomes in lyophilized form was achieved using an appropriate cryoprotectant. In conclusion, these encouraging results demonstrate the advantages of exploring novel therapeutic targets and compounds, particularly when associated to liposomes as a delivery system, to potentiate their safety and therapeutic effectiveness for cancer management.

2021-09Doctoral thesis

Open access