Publications by authors named "Dailson Nogueira de Souza"

7 Publications

  • Page 1 of 1

Agomelatine reduces circulating triacylglycerides and hepatic steatosis in fructose-treated rats.

Biomed Pharmacother 2021 Jun 11;141:111807. Epub 2021 Jun 11.

Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Zip Code: 13083-881, Campinas, SP, Brazil. Electronic address:

Agomelatine (AGO) is an antidepressant drug with agonistic activity at melatonin receptor 1 (MT1) and MT2 and with neutral antagonistic activity at serotonin receptor 5-HT2. Although experimental studies show that melatonin reduces hypertriglyceridemia and hepatic steatosis induced by excessive fructose intake, no studies have tested if AGO exerts similar actions. To address this issue we have treated male Wistar rats with fructose (15% in the drinking water) and/or AGO (40 mg/kg/day) for two weeks. AGO reduced body weight gain, feeding efficiency and hepatic lipid levels without affecting caloric intake in fructose-treated rats. AGO has also decreased very low-density lipoprotein (VLDL) production and circulating TAG levels after an oral load with olive oil. Accordingly, treatment with AGO reduced the hepatic expression of fatty acid synthase (Fasn), a limiting step for hepatic de novo lipogenesis (DNLG). The expression of apolipoprotein B (Apob) and microsomal triglyceride transfer protein (Mttp) in the ileum, two crucial proteins for intestinal lipoprotein production, were also downregulated by treatment with AGO. Altogether, the present data show that AGO mimics the metabolic benefits of melatonin when used in fructose-treated rats. This study also suggests that it is relevant to evaluate the potential of AGO to treat metabolic disorders in future clinical trials.
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http://dx.doi.org/10.1016/j.biopha.2021.111807DOI Listing
June 2021

Dexamethasone programs lower fatty acid absorption and reduced PPAR-γ and fat/CD36 expression in the jejunum of the adult rat offspring.

Life Sci 2021 Jan 13;265:118765. Epub 2020 Nov 13.

Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Campinas, SP 13083-881, Brazil. Electronic address:

The progeny of rats born and breastfed by mothers receiving dexamethasone (DEX) during pregnancy exhibits permanent reduction in body weight and adiposity but the precise mechanisms related to this programming are not fully understood. In order to clarify this issue, the present study investigated key aspects of lipoprotein production and lipid metabolism by the liver and the intestine that would explain the reduced adiposity seen in the adult offspring exposed to DEX in utero. Female Wistar rats were treated with DEX (0.1 mg/kg/day) between the 15th and the 21st days of pregnancy, while control mothers were treated with vehicle. Male offspring born to control mothers were nursed by either adoptive control mothers (CTL/CTL) or DEX-treated mothers (CTL/DEX). Male offspring born to DEX-treated mothers were nursed by either control mothers (DEX/CTL) or adoptive DEX-treated mothers (DEX/DEX). We found that only the male DEX/DEX offspring had reduced adiposity. Additionally, male DEX/DEX progeny had lower circulating triacylglycerol (TAG) levels only in fed-state. The four groups of offspring presented similar energy expenditure, respiratory quotient and very low-density lipoprotein (VLDL) production. On the other hand, DEX/DEX rats displayed reduced TAG levels after gavage with olive oil and reduced expression of fatty acid translocase Cd36 (Fat/Cd36) and peroxisome proliferator-activated receptor γ (Pparg) in the jejunum. Altogether, our study supports the notion that reduced fat absorption by the jejunum may contribute to the lower adiposity of the adult offspring born and breastfed by mothers treated with DEX during pregnancy.
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http://dx.doi.org/10.1016/j.lfs.2020.118765DOI Listing
January 2021

In utero exposure to dexamethasone programs the development of the pancreatic β- and α-cells during early postnatal life.

Life Sci 2020 Aug 28;255:117810. Epub 2020 May 28.

Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 105 Alexander Flemming St., Campinas 13083-881, SP, Brazil. Electronic address:

Aims: The aim of the present study was to clarify if in utero exposure to DEX would affect the development of different types of pancreatic endocrine cells during postnatal life.

Main Methods: We investigated morphological and transcriptional features of both pancreatic β- and α-cell populations within the pancreatic islets during the early postnatal life of rats born to mothers treated with DEX (0.1 mg/kg) from day 14 to 19 of pregnancy. Untreated pregnant Wistar rats of the same age (12-week-old) were used as control (CTL). Pups were euthanized on the 1st, 3rd and 21st (PND1, PND3 and PND21, respectively) days of life, regardless of sex. Serum insulin and glucagon levels were also evaluated.

Key Findings: Rats born to DEX-treated mothers exhibited increased pancreatic α-cell mass, circulating glucagon levels and Gcg, Pax6, MafB and Nkx2.2 expression. Rats born to DEX-treated mothers also presented a rise in serum insulin levels on the PND3 that was paralleled by reduced β-cell mass. Such increase in serum insulin levels, instead, was associated with increased expression of genes associated to insulin secretion such as Gck and Slc2a2.

Significance: Altogether, the present data reveals yet unknown changes in endocrine pancreas during early postnatal life of rats exposed to DEX in utero. Such data may contribute to the understanding of the metabolic features of rats born to DEX-treated mothers.
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http://dx.doi.org/10.1016/j.lfs.2020.117810DOI Listing
August 2020

Long-term increase of insulin secretion in mice subjected to pregnancy and lactation.

Endocr Connect 2020 Mar 1. Epub 2020 Mar 1.

G Anhe, Department of Pharmacology, State University of Campinas, Campinas, Brazil.

Purpose: Observational studies show that longer breastfeeding periods reduce maternal risk of type 2 diabetes mellitus. However, it is currently unknown if the long-term benefits of breastfeeding for maternal glucose homeostasis are linked to changes in the endocrine pancreas.

Methods: We presently evaluated functional, morphological and molecular aspects of the endocrine pancreas of mice subjected to two sequential cycles of pregnancy and lactation (L21). Age-matched mice not allowed to breastfeed (L0) and virgin mice were used as controls.

Results: L21 mice exhibited increased tolerance and increased glucose-stimulated insulin secretion (GSIS) by isolated islets. Pancreatic islets of L21 mice did not present evident morphological changes to justify the increased GSIS. On the other hand, islets of L21 mice exhibited a reduction in Cavb3 and Kir6.2 expression with concordant increased intracellular Ca2+ levels after challenge with glucose.

Conclusion: Altogether, the present findings show the breastfeeding exerts long-term benefits for maternal endocrine pancreas by increasing intracellular Ca2+ levels and GSIS.
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http://dx.doi.org/10.1530/EC-20-0020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7159261PMC
March 2020

Dexamethasone during pregnancy impairs maternal pancreatic β-cell renewal during lactation.

Endocr Connect 2019 Feb;8(2):120-131

Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil.

Pancreatic islets from pregnant rats develop a transitory increase in the pancreatic β-cell proliferation rate and mass. Increased apoptosis during early lactation contributes to the rapid reversal of those morphological changes. Exposure to synthetic glucocorticoids during pregnancy has been previously reported to impair insulin secretion, but its impacts on pancreatic islet morphological changes during pregnancy and lactation have not been described. To address this issue, we assessed the morphological and molecular characteristics of pancreatic islets from rats that underwent undisturbed pregnancy (CTL) or were treated with dexamethasone between the 14th and 19th days of pregnancy (DEX). Pancreatic islets were analyzed on the 20th day of pregnancy (P20) and on the 3rd, 8th, 14th and 21st days of lactation (L3, L8, L14 and L21, respectively). Pancreatic islets from CTL rats exhibited transitory increases in cellular proliferation and pancreatic β-cell mass at P20, which were reversed at L3, when a transitory increase in apoptosis was observed. This was followed by the appearance of morphological features of pancreatic islet neogenesis at L8. Islets from DEX rats did not demonstrate an increase in apoptosis at L3, which coincided with an increase in the expression of M2 macrophage markers relative to M1 macrophage and T lymphocyte markers. Islets from DEX rats also did not exhibit the morphological characteristics of pancreatic islet neogenesis at L8. Our data demonstrate that maternal pancreatic islets undergo a renewal process during lactation that is impaired by exposure to DEX during pregnancy.
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http://dx.doi.org/10.1530/EC-18-0505DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6376996PMC
February 2019

The absence of lactation after pregnancy induces long-term lipid accumulation in maternal liver of mice.

Life Sci 2019 Jan 15;217:261-270. Epub 2018 Dec 15.

Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 13084-971 Campinas, Brazil. Electronic address:

Aims: The present investigation evaluated whether pregnancy followed by lactation exerts long-term impacts on maternal hepatic lipid metabolism.

Main Methods: Female mice were subjected to two pregnancies, after which they were either allowed to breastfeed their pups for 21 days (L21) or had their litter removed (L0). Age-matched virgin mice were used as controls (CTL). Three months after the second delivery, serum was collected for lipid profiling, and fragments of liver were used to assess lipid content and to evaluate the key steps of de novo non-esterified fatty acid (NEFA) synthesis, esterification and β-oxidation, very low density lipoprotein (VLDL) assembly and secretion and autophagy.

Key Findings: L0 exhibited a significant increase in hepatic TG and reduced apolipoprotein B-100 (ApoB-100) expression. L21 mice had increased ATP citrate lyase (ACLY) activity and reduced acetyl-CoA carboxylase (ACC) phosphorylation but no increased hepatic TG. On the other hand, L21 mice had reduced hepatic sequestosome 1 (SQSTM1/p62) levels. Increased high density lipoprotein (HDL) cholesterol and hepatic apolipoprotein A-1 (ApoA-1) expression were found exclusively in L21.

Significance: The present study reveals that long-term hepatic lipid accumulation is induced by the history of pregnancy without lactation. On the other hand, reduced SQSTM1/p62 levels indicate that increased autophagic flux during life may prevent hepatic fat in dams subjected to lactation. Lactation after pregnancy is also obligatory for a long-term increase in maternal HDL. The present data may contribute to the understanding of the mechanisms leading to elevated cardiometabolic risk in women limited to short periods of lactation.
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http://dx.doi.org/10.1016/j.lfs.2018.12.026DOI Listing
January 2019

Prolonged fasting elicits increased hepatic triglyceride accumulation in rats born to dexamethasone-treated mothers.

Sci Rep 2017 09 4;7(1):10367. Epub 2017 Sep 4.

Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil.

We investigated the effect of dexamethasone during the last week of pregnancy on glucose and lipid metabolism in male offspring. Twelve-week old offspring were evaluated after fasting for 12-hours (physiological) and 60-hours (prolonged). Physiological fasting resulted in glucose intolerance, decreased glucose clearance after pyruvate load and increased PEPCK expression in rats born to dexamethasone-treated mothers (DEX). Prolonged fasting resulted in increased glucose tolerance and increased glucose clearance after pyruvate load in DEX. These modulations were accompanied by accumulation of hepatic triglycerides (TG). Sixty-hour fasted DEX also showed increased citrate synthase (CS) activity, ATP citrate lyase (ACLY) content, and pyruvate kinase 2 (pkm2), glucose transporter 1 (slc2a1) and lactate dehydrogenase-a (ldha) expressions. Hepatic AKT2 was increased in 60-hour fasted DEX, in parallel with reduced miRNAs targeting the AKT2 gene. Altogether, we show that metabolic programming by prenatal dexamethasone is characterized by an unexpected hepatic TG accumulation during prolonged fasting. The underlying mechanism may depend on increased hepatic glycolytic flux due to increased pkm2 expression and consequent conversion of pyruvate to non-esterified fatty acid synthesis due to increased CS activity and ACLY levels. Upregulation of AKT2 due to reduced miRNAs may serve as a permanent mechanism leading to increased pkm2 expression.
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http://dx.doi.org/10.1038/s41598-017-10642-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5583317PMC
September 2017
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