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Papers by Roberta Squecco

Adipose tissue is a dynamic endocrine organ with a central role in metabolism regulation. Functio... more Adipose tissue is a dynamic endocrine organ with a central role in metabolism regulation. Functional differences in adipose tissue seem associated with the regional distribution of fat depots, in particular in subcutaneous and visceral omental pads. Here, we report for the first time the isolation of human adipose-derived adult stem cells from visceral omental and subcutaneous fat (V-ASCs and S-ASCs, respectively) from the same subject. Immunophenotyping shows that plastic culturing selects homogeneous cell populations of V-ASCs and S-ASCs from the corresponding stromal vascular fractions (SVFs), sharing typical markers of mesenchymal stem cells. Electron microscopy and electrophysiological and real-time RT-PCR analyses confirm the mesenchymal stem nature of both V-ASCs and S-ASCs, while no significant differences in a limited pattern of cytokine/chemokine expression can be detected. Similar to S-ASCs, V-ASCs can differentiate in vitro toward adipogenic, osteogenic, chondrogenic, muscular, and neuronal lineages, as demonstrated by histochemical, immunofluorescence, real-time RT-PCR, and electrophysiological analyses, suggesting the multipotency of such adult stem cells. Our data demonstrate that both visceral and subcutaneous adipose tissues are a source of pluripotent stem cells with multigermline potential. However, the visceral rather than the subcutaneous ASC could represent a more appropriate in vitro cell model for investigating the molecular mechanisms implicated in the pathophysiology of metabolic disorders such as obesity.

These guidelines are intended to assist authors in writing their contributions and to reduce the ... more These guidelines are intended to assist authors in writing their contributions and to reduce the subsequent editing process. The Editorial Group of Physiology News tries to ensure that all articles are written in a journalistic style so that they will have an immediate interest value for a wide readership and will be readable and comprehensible to non-experts. In particular, scientific articles should give a good overview of a field rather than focus entirely on the authors' own research. Format of articles The main message or question posed should be introduced in the first paragraph. The background for the topic should then be established, leading up to the final conclusion. Length of articles This will be determined by the subject matter and agreed with the Editorial Administrator. Submission of articles Authors should submit articles as a Word document attached to an email. Illustrations should be sent as separate attachments (see below) and not embedded in the text. Illustrations and authors' photographs Authors are encouraged to submit diagrams, drawings, photographs or other artwork with their articles or to suggest appropriate illustrations. A photograph of the author(s) should also accompany submissions, if possible. Illustrations and photographs may be colour or black and white, prints, transparencies or tif/jpeg files with a minimum resolution of 300 dpi.. Electronic colour figures should be saved in CMYK mode. References Authors are requested to keep the number of references to a minimumpreferably no more than two or three. Please cite all references in the style of

The FASEB Journal, Oct 28, 2022

Journal of Cell Science, May 1, 2009

Journal of The American Society of Nephrology, Sep 1, 2006

Regenerative medicine represents a critical clinical goal for patients with ESRD, but the identif... more Regenerative medicine represents a critical clinical goal for patients with ESRD, but the identification of renal adult multipotent progenitor cells has remained elusive. It is demonstrated that in human adult kidneys, a subset of parietal epithelial cells (PEC) in the Bowman's capsule exhibit coexpression of the stem cell markers CD24 and CD133 and of the stem cell-specific transcription factors Oct-4 and BmI-1, in the absence of lineage-specific markers. This CD24 ؉ CD133 ؉ PEC population, which could be purified from cultured capsulated glomeruli, revealed self-renewal potential and a high cloning efficiency. Under appropriate culture conditions, individual clones of CD24 ؉ CD133 ؉ PEC could be induced to generate mature, functional, tubular cells with phenotypic features of proximal and/or distal tubules, osteogenic cells, adipocytes, and cells that exhibited phenotypic and functional features of neuronal cells. The injection of CD24 ؉ CD133 ؉ PEC but not of CD24 ؊ CD133 ؊ renal cells into SCID mice that had acute renal failure resulted in the regeneration of tubular structures of different portions of the nephron. More important, treatment of acute renal failure with CD24 ؉ CD133 ؉ PEC significantly ameliorated the morphologic and functional kidney damage. This study demonstrates the existence and provides the characterization of a population of resident multipotent progenitor cells in adult human glomeruli, potentially opening new avenues for the development of regenerative medicine in patients who have renal diseases.

Frontiers in Physiology, Jul 15, 2022

Resistin, among its several actions, has been reported to exert central anorexigenic effects in r... more Resistin, among its several actions, has been reported to exert central anorexigenic effects in rodents. Some adipokines which centrally modulate food intake have also been reported to affect the activity of gastric smooth muscle, whose motor responses represent a source of peripheral signals implicated in the control of the hunger-satiety cycle through the gut-brain axis. On this basis, in the present experiments, we investigated whether resistin too could affect the mechanical responses in the mouse longitudinal gastric fundal strips. Electrical field stimulation (EFS) elicited tetrodotoxin-and atropine-sensitive contractile responses. Resistin reduced the amplitude of the EFS-induced contractile responses. This effect was no longer detected in the presence of L-NNA, a nitric oxide (NO) synthesis inhibitor. Resistin did not influence the direct muscular response to methacholine. In the presence of carbachol and guanethidine, EFS elicited inhibitory responses whose amplitude was increased by resistin. L-NNA abolished the inhibitory responses evoked by EFS, indicating their nitrergic nature. In the presence of L-NNA, resistin did not have any effect on the EFS-evoked inhibitory responses. Western blot and immunofluorescence analysis revealed a significant increase in neuronal nitric oxide synthase (nNOS) expression in neurons of the myenteric plexus following resistin exposure. In conclusion, the present results offer the first evidence that resistin acts on the gastric fundus, likely through a modulatory action on the nitrergic neurotransmission.

European Eating Disorders Review, May 3, 2021

ObjectiveThe recent conceptualization of ghrelin as a stress hormone suggested that its chronic a... more ObjectiveThe recent conceptualization of ghrelin as a stress hormone suggested that its chronic alterations may have a role in maintaining overeating behaviors in subjects with eating disorders (EDs) reporting childhood traumatic experiences. The aim of this study was to investigate the alterations of ghrelin levels in patients with EDs, their associations with early trauma, binge and emotional eating, and possible moderation/mediation models.MethodSixty‐four patients with EDs and 42 healthy controls (HCs) had their plasma ghrelin levels measured and completed questionnaires evaluating general and ED‐specific psychopathology, emotional eating, and childhood traumatic experiences.ResultsParticipants with anorexia nervosa had higher ghrelin levels than HCs in body mass index (BMI)‐adjusted comparisons. Moreover, patients reporting a history of childhood trauma had higher ghrelin levels. Childhood sexual abuse (CSA), BMI, and self‐induced vomiting were independent predictors of ghrelin levels. Moderation analyses showed that ghrelin levels were associated with binge and emotional eating only for higher levels of childhood trauma. Elevated ghrelin was a significant mediator for the association of CSA with binge eating.ConclusionsThese results support the hypothesis that chronic alterations in ghrelin levels following childhood traumatic experiences could represent a neurobiological maintaining factor of pathological overeating behaviors in EDs.

Endocrine-related Cancer, Jul 1, 2023

Pheochromocytomas/paragangliomas (PPGLs) are neuroendocrine tumours, mostly resulting from mutati... more Pheochromocytomas/paragangliomas (PPGLs) are neuroendocrine tumours, mostly resulting from mutations in predisposing genes. Mutations of succinate dehydrogenase (SDH) subunit B (SDHB) are associated with high probability of metastatic disease. Since bioelectrical properties and signalling in cancer are an emerging field, we investigated the metabolic, functional and electrophysiological characteristics in human succinate dehydrogenase subunit B (SDHB)-deficient pheochromocytoma cells. These cells exhibited reduced SDH function with elevated succinate-to-fumarate ratio and reduced intracellular ATP levels. The analysis of membrane passive properties revealed a more hyperpolarized membrane potential and a lower cell capacitance of SDHB-deficient cells compared to the parental ones. These bioelectrical changes were associated with reduced proliferation and adhesion capacity of SDHB-deficient cells. Only in SDHB-deficient cells, we also observed an increased amplitude of potassium currents suggesting an activation of ATP-sensitive potassium channels (KATP). Indeed, exposure of the SDHB-deficient cells to glibenclamide, a specific KATP inhibitor, or to ATP caused normalization of potassium current features and altered proliferation and adhesion. In this work, we show for the first time that reduced intracellular ATP levels in SDHB-deficient chromaffin cells impaired cell bioelectrical properties, which, in turn, are associated with an increased cell aggressiveness. Moreover, we first ever demonstrated that glibenclamide not only reduced the outward potassium currents in SDHB-deficient cells but increased their growth capacity, reduced their ability to migrate and shifted their phenotype towards one more similar to that of parental one.