Publications by authors named "Rosangela F Garcia"

Context: Energy homeostasis is a primary factor for the survival of mammals. Many tissues and organs, among which is the liver, keep this homeostasis in varied circumstances, including caloric restriction (CR) and physical activity.

Objective: This study investigated glucose metabolism using the following groups of eight-week-old male Swiss mice: CS, sedentary and fed freely; RS, sedentary and RT, trained, both under 30% CR ( = 20-23 per group).

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It was previously reported that liver glucose metabolism in rats under caloric restriction differs from that of freely-fed rats. This study hypothesized that these changes (1) were related to the expression of hypothalamic neuropeptides involved in metabolic control, and (2) were not a residual effect of litter size. To those purposes, liver glucose metabolism and hypothalamic expression of the orexigenic neuropeptides NPY (neuropeptide Y) and AgRP (agouti gene-related peptide); and of the anorexigenic neuropeptides POMC (pro-opiomelanocortin) and CART (cocaine- and amphetamine-related transcripts) were investigated.

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Background: Caloric restriction since birth changes glucose metabolism by the liver in overnight-fasted rats to a fed-like pattern, in which glucose output is large but gluconeogenesis is negligible. It was investigated whether these changes could be a residual effect of the nutritional condition during lactation and what could be the mechanism of such change.

Methods: Newborn rat pups were arranged in litters of 6 or 12 (G6 and G12).

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Context: Caloric restriction increases liver glucose release (LGR), but it is not known if this is a permanent condition.

Objective: To investigate if refeeding after caloric restriction reverses the high LGR.

Materials And Methods: Rats were organised in six-pups litters (GC); 12-pups litters with either 50% caloric restriction from 21 to 80 days of age (GR) or fed at will from 50 to 80 days of age (GRL).

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Vitex agnus-castus (VAC) is a plant that has recently been used to treat the symptoms of menopause, by its actions on the central nervous system. However, little is known about its actions on disturbances in lipid metabolism and nonalcoholic fat liver disease (NAFLD), frequently associated with menopause. Ovariectomized (OVX) rats exhibit increased adiposity and NAFLD 13 weeks after ovary removal and were used as animal models of estrogen deficiency.

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Background. As the liver is important for blood glucose regulation, this study aimed at relating liver glucose release stimulated by glucagon and adrenaline to in vivo episodes of hypoglycaemia. Methods.

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Estrogen deficiency is associated with aging and increases the incidence of metabolic syndrome and hypertension. In this study, the effects of tibolone, a synthetic steroid, on the cardiovascular system, liver lipid metabolism, and redox status were evaluated, in ovariectomized (OVX) rats with renovascular hypertension (two-kidneys, one-clip, OVX + 2K1C). This study encompassed direct measurements of mean arterial pressure , plasma biochemical analysis, liver lipid contents, and assessments of the mitochondrial and peroxisomal β-oxidation capacities.

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The aim of this work was to evaluate the effects of therapeutic doses of Cimicifuga racemosa on cardiovascular parameters and on liver lipid metabolism and redox status in an animal model of estrogen deficiency associated with hypertension, a condition that could make the liver more vulnerable to drug-induced injuries. Female Wistar rats were subjected to the surgical procedures of bilateral ovariectomy (OVX) and induction of renovascular hypertension (two-kidneys, one-clip; 2K1C). These animals (OVX + 2K1C) were treated with daily doses of a C.

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Article Synopsis
  • The study aimed to explore the role of mitochondrial dysfunction in non-alcoholic fatty liver disease (NAFLD) using a rat model of obesity induced by monosodium L-glutamate (MSG).
  • Results showed that liver mitochondria from these obese rats had increased fatty acid β-oxidation and oxidising capacity for succinate without impairing oxidative phosphorylation efficiency.
  • The overall findings suggested that mitochondrial dysfunction does not contribute to liver fat accumulation in this model, and enhancements in specific enzyme activities may help defend against oxidative stress.
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Aim: The acute effect of oral administration of isolated or combined glycerol, pyruvate, and L-lactate on glycemia recovery (GR) during long-term, insulin-induced hypoglycemia (IIH) was compared.

Methods: Glycemia of 24 h-fasted rats that received intraperitoneal injection (1.0 U/kg) of regular insulin (IIH group) or saline (COG group) and, 15, 150, or 165 min later, oral saline (control IIH), glycerol (100 mg/kg), pyruvate (100 mg/kg), L-lactate (100 mg/kg), or combined glycerol+pyruvate+L-lactate (each 33.

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Ketogenesis, inferred by the production of acetoacetate plus ss-hydroxybutyrate, in isolated perfused livers from 24-h fasted diabetic rats submitted to short-term insulin-induced hypoglycemia (IIH) was investigated. For this purpose, alloxan-diabetic rats that received intraperitoneal regular insulin (IIH group) or saline (COG group) injection were compared. An additional group of diabetic rats which received oral glucose (gavage) (100 mg kg(-1)) 15 min after insulin administration (IIH + glucose group) was included.

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Gluconeogenesis in livers from overnight fasted weaned rats submitted to short-term insulin-induced hypoglycaemia (IIH) was investigated. For this purpose, a condition of hyperinsulinemia/hypoglycaemia was obtained with an intraperitoneal (ip) injection of regular insulin (1.0 U kg(-1)).

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In this study, the contribution of liver glycogenolysis and gluconeogenesis in the defense against short-term insulin induced hypoglycemia (IIH) was investigated. For this purpose, we used an experimental model in which IIH was obtained by administering an IP injection of a pharmacological dose (1 U/kg) of regular insulin to rats that had been deprived of food for a period of six hours. This experimental model is suitable to study the simultaneous participation of glycogen breakdown and gluconeogenesis in the defense against IIH.

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Aim: The acute effects of the oral administration of L-alanine (L-ala), L-glutamine (L-gln), L-ala+L-gln, and L-alanyl-L-glutamine (AGP) on glycemia recovery during short-term insulin-induced hypoglycemia (IIH) were compared.

Methods: For this purpose, the blood glucose levels of 24-h-fasted rats that received intraperitoneal injections of regular insulin (IIH group) or saline [control (COG) group] and, 15 min later, oral administration of L-ala (100 mg/kg), L-gln (100 mg/kg), L-ala (50 mg/kg)+L-gln (50 mg/kg), or AGP (100 mg/kg) were compared. Liver perfusion experiments and blood collection to measure blood glucose levels were performed 30 min after insulin (1.

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