Papers by Susanna Antoniotti
International Journal of Molecular Sciences
Endothelial function is essential in the maintenance of systemic homeostasis, whose modulation st... more Endothelial function is essential in the maintenance of systemic homeostasis, whose modulation strictly depends on the proper activity of tissue-specific angiocrine factors on the physiopathological mechanisms acting at both single and multi-organ levels. Several angiocrine factors take part in the vascular function itself by modulating vascular tone, inflammatory response, and thrombotic state. Recent evidence has outlined a strong relationship between endothelial factors and gut microbiota-derived molecules. In particular, the direct involvement of trimethylamine N-oxide (TMAO) in the development of endothelial dysfunction and its derived pathological outcomes, such as atherosclerosis, has come to light. Indeed, the role of TMAO in the modulation of factors strictly related to the development of endothelial dysfunction, such as nitric oxide, adhesion molecules (ICAM-1, VCAM-1, and selectins), and IL-6, has been widely accepted. The aim of this review is to present the latest studi...
International Journal of Molecular Sciences
Trimethylamine N-oxide (TMAO) is a diet derived compound directly introduced through foodstuff, o... more Trimethylamine N-oxide (TMAO) is a diet derived compound directly introduced through foodstuff, or endogenously synthesized from its precursors, primarily choline, L-carnitine, and ergothioneine. New evidence outlines high TMAO plasma concentrations in patients with overt cardiovascular disease, but its direct role in pathological development is still controversial. The purpose of the study was to evaluate the role of TMAO in affecting key intracellular factors involved in endothelial dysfunction development, such as reactive oxygen species, mitochondrial health, calcium balance, and nitric oxide release using bovine aortic endothelial cells (BAE-1). Cell viability and oxidative stress indicators were monitored after acute and prolonged TMAO treatment. The role of TMAO in interfering with the physiological purinergic vasodilatory mechanism after ATP stimulation was defined through measurements of the rise of intracellular calcium, nitric oxide release, and eNOS phosphorylation at Se...
Joint Meeting of the Federation of European Physiological Societies (FEPS) and the Italian Physiological Society (SIF), 2019
Vascular Pharmacology, 2018
results we here assess their interactions with human cerebral microvascular cells (hCMEC/D3) as i... more results we here assess their interactions with human cerebral microvascular cells (hCMEC/D3) as in vitro BBB model. Our in vitro experiments by means of both the electrophysiological approach and the simultaneous calcium imaging will disclose if any active modulation on neuronal activities does occur after ex vivo and in vivo NPs administration. The obtained results will help us to better define the safety profile and active properties of NPs specifically developed to cross the BBB and to delivery their payload to the CNS.
BioMed Research International, 2018
Catestatin is a cationic and hydrophobic peptide derived from the enzymatic cleavage of the proho... more Catestatin is a cationic and hydrophobic peptide derived from the enzymatic cleavage of the prohormone Chromogranin A. Initially identified as a potent endogenous nicotinic–cholinergic antagonist, Catestatin has recently been shown to act as a novel regulator of cardiac function and blood pressure and as a cardioprotective agent in both pre- and postconditioning through AKT-dependent mechanisms. The aim of this study is to investigate the potential role of Catestatin also on cardiac metabolism modulation, particularly on cardiomyocytes glucose uptake. Experiments were performed on isolated adult rat cardiomyocytes. Glucose uptake was assessed by fluorescent glucose incubation and confocal microscope analysis. Glut4 plasma membrane translocation was studied by immunofluorescence experiments and evaluation of the ratio peripheral vs internal Glut4 staining. Furthermore, we performed immunoblot experiments to investigate the involvement of the intracellular pathway AKT/AS160 in the Cat...
66th SIF National Congress, 2015
The repressor element-1 silencing transcription factor (REST) has emerged as a key controller of ... more The repressor element-1 silencing transcription factor (REST) has emerged as a key controller of neuronal differentiation and has been shown to play a critical role in the expression of the neuronal phenotype; however, much has still to be learned about its role at specific developmental stages and about the functional targets affected. Among these targets, calcium signaling mechanisms are critically dependent on the developmental stage and their full expression is a hallmark of the mature, functional neuron. We have analyzed the role played by REST in GN11 cells, an immortalized cell line derived from gonadotropin hormone releasing hormone (GnRH) neurons at an early developmental stage, electrically non-excitable and with a strong migratory activity. We show for the first time that functional voltage-dependent calcium channels are expressed in wild type GN11 cells; down-regulation of REST by a silencing approach shifts these cells towards a more differentiated phenotype, increasing the functional expression of P/Q-type channels and reducing their migratory potential.
The FASEB Journal, 2005
Several peptides, including vascular endothelial growth factor (VEGF) and basic fibroblast growth... more Several peptides, including vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), activate the release of arachidonic acid (AA) and nitric oxide (NO) in endothelial cells (ECs). Both messengers are involved in EC proliferation and vascular permeability and control calcium homeostasis in different ways. Interestingly, it has been recently suggested that NO acts as a downstream mediator of AA-induced calcium entry in smooth muscle cells and isolated mouse parotid cells. In this paper, we have investigated the complex relationships that link intracellular calcium, AA, and NO in cultured endothelial cells. Using different experimental approaches, mainly simultaneous Ca 2+ and NO fluorimetric confocal imaging, we provide evidence for a complex pathway leading to noncapacitative calcium entry (NCCE) in bovine aortic endothelial cells (BAECs). In particular, AA is able to induce NCCE through two different pathways: one dependent on eNOS recruitment and NO release, the other NO-independent. Finally, we show that NO increase is involved in the control of BAEC proliferation. Key words: calcium channels • proliferation • signal transduction • angiogenesis • inflammation everal angiogenic and proinflammatory factors that act through tyrosine kinase receptors (RTKs), including the vascular endothelial growth factor (VEGF) and the basic fibroblast growth factor (bFGF), trigger the intracellular production of arachidonic acid (AA) and nitric oxide (NO) and of their metabolites, and activate calcium signals in different types of endothelial cells (ECs) (1-4). Both these intracellular messengers and their metabolism are strictly related to angiogenic progression and vascular rearrangement associated with different acute and chronic physiopathological conditions, such as hypertension, atherosclerosis, diabetes, cerebral ischemia, and septic shock (5-10). VEGF is of particular interest in the context of inflammation because it increases vascular permeability and is a potent angiogenic factor. VEGF acts, in part, through eNOS-derived NO, and both VEGF-induced angiogenesis and permeability are dependent on NO produced by S
Recent Patents on Anti-Cancer Drug Discovery, 2012
An increasing body of evidence suggests the involvement of hydrogen sulfide (H2S) in different ph... more An increasing body of evidence suggests the involvement of hydrogen sulfide (H2S) in different physiological and pathological processes. Similarly to the other gasotransmitters nitric oxide (NO) and carbon monoxide (CO), this bioactive compound is rapidly diffusible through the biological membranes and acts in a paracrine fashion. Despite the large amount of biological actions observed in vitro and in vivo upon stimulation with H2S donors, as well as by interfering with its synthesis, the molecular targets and mechanisms through which it exerts its intracellular effects are only partially known. A number of proteins are covalently modified by H2S through sulfhydration of specific cysteine residues. However, only in few cases their identity has been discovered and the functional role of this post-translational modification needs to be investigated in more detail. Great attention has been devoted to potassium channels, particularly KATP, as they are considered key mediators of H2S-induced effects, and their sulfhydration has been clearly demonstrated. Recently, different authors reported the ability of H2S to interfere with calcium homeostasis in neurons, cardiomyocytes and endothelial cells. Since calcium signaling is involved in all cell processes, these observations attracted increasing attention from basic biology and medicine. Although some effects of H2S on calcium signals can be ascribed to KATP modulation, there is growing consensus about the existence of other targets for the gasotransmitter. Some of them are Ca 2+ -permeable channels. In this review we discuss the state of the art in this specific field, providing an updated report of H2S interaction with Ca 2+ channels and its functional outcomes.
Molecular Cancer Research, 2008
Growth factor–induced intracellular calcium signals in endothelial cells regulate cytosolic and n... more Growth factor–induced intracellular calcium signals in endothelial cells regulate cytosolic and nuclear events involved in the angiogenic process. Among the intracellular messengers released after proangiogenic stimulation, arachidonic acid (AA) plays a key role and its effects are strictly related to calcium homeostasis and cell proliferation. Here, we studied AA-induced intracellular calcium signals in endothelial cells derived from human breast carcinomas (B-TEC). AA promotes B-TEC proliferation and organization of vessel-like structures in vitro. The effect is directly mediated by the fatty acid without a significant contribution of its metabolites. AA induces Ca2+i signals in the entire capillary-like structure during the early phases of tubulogenesis in vitro. No such responses are detectable in B-TECs organized in more structured tubules. In B-TECs growing in monolayer, AA induces two different signals: a Ca2+i increase due to Ca2+ entry and an inhibition of store-dependent C...
Journal of Cellular and Molecular Medicine, 2004
The progression through the cell cycle in non-transformed cells is under the strict control of ex... more The progression through the cell cycle in non-transformed cells is under the strict control of extracellular signals called mitogens, that act by eliciting complex cascades of intracellular messengers. Among them, increases in cytosolic free calcium concentration have been long realized to play a crucial role; however, the mechanisms coupling membrane receptor activation to calcium signals are still only partially understood, as are the pathways of calcium entry in the cytosol. This article centers on the role of calcium influx from the extracellular medium in the control of proliferative processes, and reviews the current understanding of the pathways responsible for this influx and of the second messengers involved in their activation.
Current Medicinal Chemistry, 2004
Cell Calcium, 1995
The role of mitogen-activated calcium influx from the extracellular medium in the control of cell... more The role of mitogen-activated calcium influx from the extracellular medium in the control of cell proliferation was studied in Balb-c 3T3 fibroblasts. Stimulation of serumdeprived, quiescent cells with 10% foetal calf serum (FCS) induced a long-lasting (up to 70 min) elevation of intracellular free calcium concentration ([Ca*']$ Both the sustained [Ca*']i increase and the related inward current, described in a previous paper [Lovisolo D. Munaron L. Baccino FM. Bonelli G. (1992) Potassium and calcium currents activated by foetal calf serum in Balb-c 3T3 fibroblasts. Biochim. Biophys. Acta, 1104, 73-821, could be abolished either by chelation of extracellular calcium with EGTA or by SK&F 96365, an imidazole derivative that can block receptor-activated calcium channels. The effect of the abolition of these ionic signals on FCS-induced proliferation was investigated by adding either EGTA or SK&F 96365 to the culture medium during the first hours of stimulation of quiescent cells with 10% FCS. As measured after 24 h, a 22% inhibition of growth was observed when SK&F 96365 was added for the first hour, and stronger inhibitions, up to 56%, were obtained by adding the blocker for the first 2 or 4 h. Similar effects were observed with addition of 3 mM EGTA, though the inhibition was less marked for the 4 h treatment. By contrast, incubation with either substance in the next 4 h of serum stimulation did not influence cell growth, except for a slight inhibition observed when SK&F 96365 was applied from the 4th to the 8th hour. The reduction in growth resulting from the abolition of the early calcium influx was paralleled by an accumulation of cells in the G2/M phase. Both growth inhibition and G2/M accumulation were reversible, since after further 24 h in 10% FCS cells had fully recovered the exponential growth. These data indicate that the early calcium influx seen in response to mitogen stimulation develops on a timescale long enough to play a significant role in cell cycle progression, and that its block in the early GI phase can lead to a reduction of proliferation by arresting cells in later stages of the cycle.
International Journal of Molecular Sciences, 2019
Trimethylamine N-oxide (TMAO) is an organic compound derived from dietary choline and L-carnitine... more Trimethylamine N-oxide (TMAO) is an organic compound derived from dietary choline and L-carnitine. It behaves as an osmolyte, a protein stabilizer, and an electron acceptor, showing different biological functions in different animals. Recent works point out that, in humans, high circulating levels of TMAO are related to the progression of atherosclerosis and other cardiovascular diseases. However, studies on a direct role of TMAO in cardiomyocyte parameters are still limited. The purpose of this work is to study the effects of TMAO on isolated adult rat cardiomyocytes. TMAO in both 100 µM and 10 mM concentrations, from 1 to 24 h of treatment, does not affect cell viability, sarcomere length, intracellular ROS, and mitochondrial membrane potential. Furthermore, the simultaneous treatment with TMAO and known cardiac insults, such as H2O2 or doxorubicin, does not affect the treatment’s effect. In conclusion, TMAO cannot be considered a direct cause or an exacerbating risk factor of car...
Antioxidants
Squalene (SQ) is a natural triterpene widely distributed in nature. It is a metabolic intermediat... more Squalene (SQ) is a natural triterpene widely distributed in nature. It is a metabolic intermediate of the sterol biosynthetic pathway and represents a possible target in different metabolic and oxidative stress-related disorders. Growing interest has been focused on SQ’s antioxidant properties, derived from its chemical structure. Strong evidence provided by ex vivo models underline its scavenging activity towards free radicals, whereas only a few studies have highlighted its effect in cellular models of oxidative stress. Given the role of unbalanced free radicals in both the onset and progression of several cardiovascular diseases, an in depth evaluation of SQ’s contribution to antioxidant defense mechanisms could represent a strategic approach in dealing with these pathological conditions. At present experimental results overall show a double-edged sword role of squalene in cardiovascular diseases and its function has to be better elucidated in order to establish intervention line...
Frontiers in Physiology
Ischemic heart disease (IHD) is a multifactorial pathological condition strictly related to genet... more Ischemic heart disease (IHD) is a multifactorial pathological condition strictly related to genetic, dietary, and lifestyle factors. Its morbidity and mortality rate represent one of the most important pathological issues that today involve younger people in a stronger way than in the past. IHD clinical outcomes are difficult to treat and have a high economic impact on health care. So prevention of this pathological condition through cardioprotective maneuvers represents the first line of intervention, as already underlined by several animal and human studies. Even if the time of intervention is important to prevent severe outcomes, many studies highlight that sex-dependent responses are crucial for the result of cardioprotective procedures. In this scenario sexual hormones have revealed an important role in cardioprotective approach, as women seem to be more protected toward cardiac insults when compared to male counterparts. The aim of this mini review is to show the molecular pat...
Nutrients
Skeletal muscle plays a pivotal role in whole-body glucose metabolism, accounting for the highest... more Skeletal muscle plays a pivotal role in whole-body glucose metabolism, accounting for the highest percentage of glucose uptake and utilization in healthy subjects. Impairment of these key functions occurs in several conditions including sedentary lifestyle and aging, driving toward hyperglycemia and metabolic chronic diseases. Therefore, strategies pointed to improve metabolic health by targeting skeletal muscle biochemical pathways are extremely attractive. Among them, we focused on the natural sesquiterpene and cannabinoid type 2 (CB2) receptor agonist Trans-β-caryophyllene (BCP) by analyzing its role in enhancing glucose metabolism in skeletal muscle cells. Experiments were performed on C2C12 myotubes. CB2 receptor membrane localization in myotubes was assessed by immunofluorescence. Within glucose metabolism, we evaluated glucose uptake (by the fluorescent glucose analog 2-NBDG), key enzymes of both glycolytic and oxidative pathways (by spectrophotometric assays and metabolic ra...
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Papers by Susanna Antoniotti