Layanne Araujo

Dr. Layanne Araujo

orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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FCFelipe Nunes de Camargo
Felipe Nunes de Camargo
SMSandro Leão Matos
Sandro Leão Matos
LALayanne Araujo
Layanne Araujo
CCCarla Carvalho
Carla Carvalho
AAAndressa Amaral
Andressa Amaral
JCJoao Paulo Camporez
Joao Paulo Camporez
One of the consequences of the Western lifestyle and high-fat diet is non-alcoholic fatty liver disease (NAFLD) and its aggressive form, non-alcoholic steatohepatitis (NASH), which can progress to cirrhosis and hepatocellular carcinoma (HCC) and is rapidly becoming the leading cause of end-stage liver disease or liver transplantation. Currently, rodent NASH models lack significant aspects of the full NASH spectrum, representing a major problem for NASH research. Therefore, this work aimed to characterize a fast rodent model with all characteristic features of NASH. Eight-week-old male ApoE KO mice were fed with Western diet (WD), high fatty diet (HFD) or normal chow (Chow) for 7 weeks. Whole-body fat was increased by ~2 times in WD mice and HFD mice and was associated with increased glucose intolerance, hepatic triglycerides, and plasma ALT and plasma AST compared with Chow mice. WD mice also showed increased galectin-3 expression compared with Chow or HFD mice and increased plasma cholesterol compared with Chow mice. WD and HFD displayed increased hepatic fibrosis and increased F4/80 expression. WD mice also displayed increased levels of plasma MCP-1. Hepatic inflammatory markers were evaluated, and WD mice showed increased levels of TNF-α, MCP-1, IL-6 and IFN-γ. Taken together, these data demonstrated that the ApoE KO mouse fed with WD is a great model for NASH research, once it presents the fundamental parameters of the disease, including hepatic steatosis, fibrosis, inflammation, and metabolic syndrome.

3 January 2025 in Pathophysiology
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EAEster dos Santos Alves
Ester dos Santos Alves
JSJessica Denielle Matos dos Santos
Jessica Denielle Matos dos Santos
ACAlessandra G. Cruz
Alessandra G. Cruz
FCFelipe Nunes de Camargo
Felipe Nunes de Camargo
CTCarlos Zanello Talarico
Carlos Zanello Talarico
JCJoao Paulo Camporez
Joao Paulo Camporez
Background/Objectives: Metabolic dysfunction-associated steatotic liver disease (MASLD) is associated with cardiometabolic risk. Although studies have shown that estradiol positively contributes to energy metabolism via estrogen receptor alpha (ERα), its role specifically in the liver is not defined. Therefore, this study aimed to evaluate the effects of ERα overexpression, specifically in the liver in mice fed a high-fat diet (HFD). Methods: Male C57BL/6J mice were divided into four groups, vehicle fed with regular chow (RC) (RC-Vehicle); vehicle fed an HFD (HFD-Vehicle); AAV-treated fed with RC (RC-AAV); and AAV-treated fed an HFD (HFD-AAV), for 6 weeks (8–10 mice per group). AAV was administered intravenously to induce ERα overexpression. Results: We demonstrate that overexpression of ERα in RC-fed mice reduces body fat (28%). These mice show increased oxygen consumption in cultured primary hepatocytes, both in basal (19%) and maximal respiration (34%). In HFD-fed mice, we showed a decrease in hepatic TAG content (43%) associated with improved hepatic insulin sensitivity (145%). Conclusions: From this perspective, our results prove that hepatic ERα signaling is responsible for some of the metabolic protective effects of estrogen in mice. Overexpression of ERα improves hepatocyte mitochondrial function, consequently reducing hepatic lipid accumulation and protecting animals from hepatic steatosis and hepatic insulin resistance. Further investigations will be needed to determine the exact molecular mechanism by which ERα improves hepatic metabolic health.

29 January 2020 in Marine Drugs
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LALayanne Araujo
Layanne Araujo
ABAline de Freitas Brito
Aline de Freitas Brito
ISIara Souza
Iara Souza
PFPaula B. Ferreira
Paula B. Ferreira
LVLuiz Vasconcelos
Luiz Vasconcelos
PSPatricia Mirella da Silva
Patricia Mirella da Silva
The blue alga Spirulina platensis has presented several pharmacological activities, highlighting its actions as an anti-inflammatory and antioxidant. In addition, there are few studies with the influence of strength training on physiological parameters, as intestinal contractility and oxidative cell damage. We evaluated the influence of S. platensis supplementation, strength training, and its association on contractile reactivity of rat ileum, as well as the balance of oxidative stress/antioxidant defenses. Methods: Male Wistar rats were divided into; sedentary (S); S + supplemented with algae at 50 (S50), 150 (S150), and 500 mg/kg (S500); trained (T); and T + supplemented (T50, T150, and T500). Contractile reactivity was analyzed by kymographs; oxidative stress on ileum by the malondialdehyde (MDA) formation; and the antioxidant capacity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. S. platensis supplementation reduced the reactivity of rat ileum to carbachol (CCh) and KCl, while training reduced only the CCh efficacy. In addition, association potentiated the reduction on contractile reactivity. Supplementation reduced the oxidative stress and increased oxidation inhibition; training alone did not alter this parameter, however association potentiated this beneficial effect. Therefore, this study demonstrated that both supplementation and its association with strength training promote beneficial effects regarding intestinal contractile reactivity and oxidative stress, providing new insights for intestinal disorders management.

3 February 2020 in Gastroenterology Research and Practice
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LALayanne Araujo
Layanne Araujo
SBSilvana Bordin
Silvana Bordin
CCCarla R. O. Carvalho
Carla R. O. Carvalho
The expression levels of some reference genes and proteins are used for data normalization and quantification. However, these levels can change in response to experimental conditions or treatments. Aim. The aim of this work was to evaluate reference gene and protein expression in models of nonalcoholic fatty liver disease, using mice fed with a high-fat diet (HFD) and mice that are genetically obese (ob/ob). Main Methods. Histological staining techniques were used to verify the morphology and quantify the amount of lipid droplets present in the liver. Real-time polymerase chain reaction and immunoblotting were employed for monitoring protein expression and gene expression levels, respectively. Key Finding. The results showed that there was a substantial increase in the amount of lipid droplets in the livers of HFD and ob/ob animals when compared to the standard diet (SD) group. There was an observed reduction in the expression of β-actin (10%), α-tubulin (6%), GAPDH (19%), and RPL3 (15%) genes when comparing the ob/ob group to the HFD group. Additionally, the ob/ob mice displayed GAPDH protein levels that were substantially, but not significantly, reduced when compared to SD. Significance. It was concluded that there are slight differences in the expression levels of reference genes and proteins in these two NAFLD animal models, and researchers should consider these alterations when working with these models.

16 September 2015 in BMC Complementary and Alternative Medicine
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ISIara Leão Luna de Souza
Iara Leão Luna de Souza
ACAna Carolina de Carvalho Correia
Ana Carolina de Carvalho Correia
LALayanne Araujo
Layanne Araujo
LVLuiz Vasconcelos
Luiz Vasconcelos
MSMaria da Conceição Correia Silva
Maria da Conceição Correia Silva
PSPatricia Mirella da Silva
Patricia Mirella da Silva
Xylopia frutescens Aubl. (embira, semente-de-embira or embira-vermelha), is used in folk medicine as antidiarrheal. The essential oil from its leaves (XF-EO) has been found to cause smooth muscle relaxation. Thus, the aim of this study was to investigate the spasmolytic action by which XF-EO acts on guinea pig ileum. The components of the XF-EO were identified by gas chromatography-mass spectrometry. Segments of guinea pig ileum were suspended in organ bath containing modified Krebs solution at 37 °C, bubbled with carbogen mixture under a resting tension of 1 g. Isotonic contractions were registered using kymographs and isometric contractions using force transducer coupled to an amplifier and computer. Fluorescence measurements were obtained with a microplate reader using Fluo-4. Forty-three constituents were identified in XF-EO, mostly mono- and sesquiterpenes. XF-EO has been found to cause relaxation on guinea pig ileum. The essential oil inhibited in a concentration-dependent manner both CCh- and histamine-induced phasic contractions, being more potent on histamine-induced contractions as well as antagonized histamine-induced cumulative contractions in a non-competitive antagonism profile. XF-EO relaxed in a concentration-dependent manner the ileum pre-contracted with KCl and histamine. Since the potency was smaller in organ pre-contracted with KCl, it was hypothesized that XF-OE would be acting as a K+ channel positive modulator. In the presence of CsCl (non-selective K+ channel blocker), the relaxant potency of XF-OE was not altered, indicating a non-participation of these channels. Moreover, XF-EO inhibited CaCl2-induced cumulative contractions in a depolarizing medium nominally without Ca2+ and relaxed the ileum pre-contracted with S-(-)-Bay K8644 in a concentration-dependent manner, thus, was confirmed the inhibition of Ca2+ influx through Cav1 by XF-EO. In cellular experiments, the viability of longitudinal layer myocytes from guinea pig ileum was not altered in the presence of XF-OE and the Fluo-4-associated fluorescence intensity in these intestinal myocytes stimulated by histamine was reduced by the essential oil, indicating a [Ca2+]c reduction. Spasmolytic action mechanism of XF-EO on guinea pig ileum can involve histaminergic receptor antagonism and Ca2+ influx blockade, which results in [Ca2+]c reduction leading to smooth muscle relaxation.

27 August 2026 in Cells
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ASAnne Raissa Melo Santos
Anne Raissa Melo Santos
ACAlessandra G. Cruz
Alessandra G. Cruz
FCFelipe Nunes de Camargo
Felipe Nunes de Camargo
JSJessica Denielle Matos dos Santos
Jessica Denielle Matos dos Santos
JMJorge Felipe Argenta Model
Jorge Felipe Argenta Model
JCJoao Paulo Camporez
Joao Paulo Camporez
Metabolic dysfunction-associated steatohepatitis (MASH) is characterized by hepatic steatosis, inflammation, fibrosis, and metabolic dysfunction, with limited therapeutic options currently available. This study investigated whether pharmacological inhibition of Galectin-3 (Gal-3), a β-galactoside-binding lectin implicated in inflammation and fibrosis, using modified citrus pectin (MCP), attenuates established MASH in ApoE-deficient mice. Mice were assigned to four groups: standard chow (CTL), standard chow plus MCP (CTL + MCP), Western diet with fructose-enriched drinking water (WD), and WD plus MCP (WD + MCP). MCP (1% in drinking water) was administered during the final four weeks of the 11-week experimental protocol, after the establishment of metabolic dysfunction and hepatic steatosis. Compared with untreated WD mice, WD + MCP mice exhibited improved glucose tolerance, as evidenced by a 22.9% reduction in glucose area under the curve (p = 0.01), and enhanced hepatic insulin signaling, reflected by a 254.1% increase in insulin-stimulated AKT2 phosphorylation (p = 0.0002). MCP treatment also reduced hepatic lipid accumulation (39.8%, p = 0.0055) and hepatic triglyceride content (26.1%, p = 0.0003), accompanied by reductions in circulating triglyceride and cholesterol concentrations. Furthermore, WD + MCP mice exhibited reduced hepatic Gal-3 expression (25.8%, p = 0.0199), decreased F4/80 immunoreactivity (49.2%, p = 0.0061), attenuated JNK phosphorylation (46.6%, p = 0.0118), reduced collagen deposition (47.0%, p = 0.0002), and lower plasma ALT (52.9%, p = 0.0009) and AST (48.8%, p = 0.04) activities. Collectively, these findings demonstrate that MCP attenuates multiple metabolic, inflammatory, fibrotic, and hepatic injury features of established Western diet-induced MASH, supporting Gal-3 as a promising therapeutic target and MCP as a potential pharmacological strategy for MASH.