Publications by authors named "Patricia C Borck"

Disruption of biological rhythms due to exposure to artificial light at night (ALAN) has emerged as a new risk factor for metabolic diseases. However, the effects of ALAN exposure on energy metabolism with concomitant misalignment in the circadian system caused by nutritional imbalance remain largely unexplored. Here, we evaluate whether a low-protein (LP) diet could enhance the effects induced by exposure to ALAN on the energy metabolism and consequently predispose to metabolic disorders.

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Epigenetic mechanisms involve the placing (writing) or removal (erasing) of histone modifications that allow heterochromatin to transition to the open, activated euchromatin state necessary for transcription. A third, less studied epigenetic pathway involves the reading of these specific histone marks once placed. The BETs (bromodomain and extraterminal-containing protein family), which includes BRD2, BRD3, and BRD4 and the testis-restricted BRDT, are epigenetic reader proteins that bind to specific acetylated lysine residues on histone tails where they facilitate the assembly of transcription complexes including transcription factors and transcriptional machinery like RNA Polymerase II.

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Here, we investigate the effects of exercise training on glucose- and cholinergic-induced insulin secretion in pancreatic islets from obese and lean rats. Male Wistar rats were treated with monosodium glutamate (MSG) for the first 5 days of life, while control (CON) rats received saline. At 21 days, the rats were divided into exercised (EXE) and sedentary (SED) groups.

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This study investigated the effects of freeze-dried jaboticaba peel (FJP) and jaboticaba tea (JE) on obesity parameters of diet-induced obese rats. Thirty-six male Wistar rats were distributed into six groups: AIN-93 M feed a normal control diet; HFF (obese control) feed a high-fat and fructose diet; Prevention FJP (P. FJP) and Treatment FJP (T.

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The beneficial actions of L-taurine (Tau) against glucose intolerance, obesity, type 2 diabetes (T2D), and non-alcoholic fat liver disease (NAFLD) have been linked to its antioxidant and anti-inflammatory effects, which ameliorate tissue insulin sensitivity. Importantly, there are several lines of evidence that indicate a direct action of Tau on the endocrine pancreas to regulate the secretion and paracrine actions of insulin, glucagon, and somatostatin. Furthermore, Tau can also ameliorate glucose metabolism through the enhancement of insulin signaling.

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Article Synopsis
  • Overnutrition leads to significant changes in circadian rhythms related to fat metabolism in mouse liver, although the exact mechanisms remain unclear.
  • Diet-induced obesity causes increased rhythmic activity of key proteins like SREBP and PPARα, which regulate fatty acid synthesis and oxidation in a time-sensitive manner.
  • The study suggests that manipulating PPARα could allow for improved effectiveness of lipid-lowering medications, showing how overnutrition can influence metabolic health through circadian processes.
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Objective: The exposure to artificial light at night (ALAN) disrupts the biological rhythms and has been associated with the development of metabolic syndrome. MicroRNAs (miRNAs) display a critical role in fine-tuning the circadian system and energy metabolism. In this study, we aimed to assess whether altered miRNAs expression in the liver underlies metabolic disorders caused by disrupted biological rhythms.

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The sulfur-containing amino acid, taurine (Tau), regulates glucose and lipid homeostasis under normal, pre- and diabetic conditions. Here, we aimed to verify whether Tau supplementation exerts its beneficial effects against obesity, hyperglycemia and alterations in islet functions, in leptin-deficient obese (ob/ob), over a long period of treatment. From weaning until 12 months of age, female ob/ob mice received, or not, 5% Tau in drinking water (obTau group).

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Prolonged exercise has positive metabolic effects in obese or diabetic individuals. These effects are usually ascribed to improvements in insulin sensitivity. We evaluated whether exercise also generates circulating signals that protect human and rodent β cells against endoplasmic reticulum (ER) stress and apoptosis.

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Disruption of insulin secretion and clearance both contribute to obesity-induced hyperinsulinemia, though reduced insulin clearance seems to be the main factor. The liver is the major site for insulin degradation, a process mainly coordinated by the insulin-degrading enzyme (IDE). The beneficial effects of taurine conjugated bile acid (TUDCA) on insulin secretion as well as insulin sensitivity have been recently described.

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Changes in nutritional state may alter circadian rhythms through alterations in expression of clock genes. Protein deficiency has a profound effect on body metabolism, but the effect of this nutrient restriction after weaning on biological clock has not been explored. Thus, this study aims to investigate whether the protein restriction affects the daily oscillation in the behavior and metabolic rhythms, as well as expression of clock genes in peripheral tissues.

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Taurine (Tau) restores β-cell function in obesity; however, its action is lost in malnourished obese rodents. Here, we investigated the mechanisms involved in the lack of effects of Tau in this model. C57BL/6 mice were fed a control diet (CD) (14% protein) or a protein-restricted diet (RD) (6% protein) for 6 wk.

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Pancreatic beta cell (β) dysfunction is an outcome of malnutrition. We assessed the role of the amplifying pathway (AMP PATH) in β cells in malnourished obese mice. C57Bl-6 mice were fed a control (C) or a low-protein diet (R).

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Low levels of plasma estrogens are associated with weight-gain, android fat distribution, and a high prevalence of obesity-related comorbidities such as glucose intolerance and type II diabetes. The mechanisms underlying the association between low levels of estrogens and impaired glucose homeostasis are not completely understood. To begin to test this, we used three-month-old female C57BL/6J mice that either underwent ovariectomy (OVX) or received a sham surgery (Sham), and we characterized glucose homeostasis.

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Objective: While bile acids are important for the digestion process, they also act as signaling molecules in many tissues, including the endocrine pancreas, which expresses specific bile acid receptors that regulate several cell functions. In this study, we investigated the effects of the conjugated bile acid TUDCA on glucose-stimulated insulin secretion (GSIS) from pancreatic β-cells.

Methods: Pancreatic islets were isolated from 90-day-old male mice.

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Aims: Fat deposition in the liver, which leads to nonalcoholic fatty liver disease is associated with obesity. Taurine (Tau) regulates lipid metabolism, representing a possible nutraceutical agent against obesity and its comorbidities. Here, we investigated whether Tau supplementation prevents hepatic lipid accumulation by regulation of the main hepatic genes involved in de novo lipogenesis and β-oxidation.

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Taurine (Tau) regulates β-cell function and glucose homeostasis under normal and diabetic conditions. Here, we assessed the effects of Tau supplementation upon glucose homeostasis and the morphophysiology of endocrine pancreas, in leptin-deficient obese (ob) mice. From weaning until 90-day-old, C57Bl/6 and ob mice received, or not, 5% Tau in drinking water (C, CT, ob and obT).

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Pancreatic β-cells are highly sensitive to suboptimal or excess nutrients, as occurs in protein-malnutrition and obesity. Taurine (Tau) improves insulin secretion in response to nutrients and depolarizing agents. Here, we assessed the expression and function of Cav and KATP channels in islets from malnourished mice fed on a high-fat diet (HFD) and supplemented with Tau.

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Backgrounds/aims: Obese rats obtained by neonatal monosodium glutamate (MSG) administration present insulin hypersecretion. The metabolic mechanism by which glucose catabolism is coupled to insulin secretion in the pancreatic β-cells from MSG-treated rats is understood. The purpose of this study was to evaluate glucose metabolism in pancreatic islets from MSG-treated rats subjected to swimming training.

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