Overweight during development dysregulates cellular metabolism and critical genes that control food intake in the prefrontal cortex.

Backgrounds And Aims: Childhood obesity is increasing substantially across the world. The World Obesity Federation (WOF) and World Health Organization (WHO) predicted that in 2030 > 1 billion people will be obese, and by 2035 over 4 billion will reach obesity worldwide. According to WHO, the world soon cannot afford the economic cost of obesity, and we need to act to stop obesity acceleration now.

The immediate effect of overnutrition and fluoxetine treatment during the critical period of development on the hippocampus.

It is well known that overnutrition, overweight, and obesity in children can modulate brain mechanisms of plasticity, monoaminergic systems, and mitochondrial function. The immediate effect of overnutrition during the developmental period has not been thoroughly examined in rats until the present. This study sought to evaluate the impact on adult rats of early life overfeeding and fluoxetine treatment from post-natal day 1 (PND1) to post-natal day 21 (PND21) relative to mitochondrial function, oxidative balance, and expression of specific monoaminergic genes in the hippocampus.

Overfeeding during development induces temporally-dependent changes in areas controlling food intake in the brains of male Wistar rats.

Aims: We sought to evaluate the effects of overfeeding during lactation on the feeding behavior and expression of specific regulatory genes in brain areas associated with food intake in 22- and 60-day old male rats.

Methods: We evaluated body weight, food intake of standard and palatable diet, and mRNA expression of dopamine receptor D1 (DDR1), dopamine receptor (DDR2), melanocortin 4 receptor (MC4R), the μ-opioid receptor (MOR), neuropeptide Y (NPY), agouti-related protein (AGRP), proopiomelanocortin (POMC), cocaine-and amphetamine-regulated transcript (CART), serotonin (5-hydroxytryptamine; 5-HT) transporter (SERT), 5-hydroxytryptamine receptor 1B (5-HT1B), 5-hydroxytryptamine receptor 2C receptor (5-HT2C), Clock (CLOK), cryptochrome protein 1 (Cry1) and period circadian protein homolog 2 (Per2) in the striatum, hypothalamus and brainstem of male rats at post-natal days (PND) 22 and 60.

Key Findings: Overfeeding resulted in significantly increased body weight through PND60, and a 2-fold increase in palatable food intake at PND22, but not at PND60.

Early life fluoxetine treatment causes long-term lean phenotype in skeletal muscle of rats exposed to maternal lard-based high-fat diet.

There is a concern about early life exposure to Selective Serotonin Reuptake Inhibitors (SSRI) in child development and motor system maturation. Little is known, however, about the interaction of environmental factors, such as maternal nutrition, associated with early exposure to SSRI. The increased maternal consumption of high-fat diets is worrisome and affects serotonin system development with repercussions in body phenotype.

Fluoxetine administration in juvenile overfed rats improves hypothalamic mitochondrial respiration and REDOX status and induces mitochondrial biogenesis transcriptional expression.

Nutritional imbalance in early life may disrupt the hypothalamic control of energy homeostasis and increase the risk of metabolic disease. The hypothalamic serotonin (5-hydroxytryptamine; 5-HT) system based in the hypothalamus plays an important role in the homeostatic control of energy balance, however the mechanisms underlying the regulation of energy metabolism by 5-HT remain poorly described. Several crucial mitochondrial functions are altered by mitochondrial stress.

Chronic serotonin reuptake inhibition uncouples brown fat mitochondria and induces beiging/browning process of white fat in overfed rats.

Aim: To investigate whether a chronic 5-HT reuptake inhibitor (i.e. Fluoxetine-FLX) exposure in young adult rats overfed during suckling period would modulate interscapular brown adipose tissue (iBAT) mitochondria and browning agents in white adipose tissue (WAT).

Body composition, biochemical, behavioral and molecular alterations in overfed rats after chronic exposure to SSRI.

Serotonin (5-HT) plays a regulatory role in coordinating the neural circuits regulating energy balance, with differences in both 5-HT availability at the synapse and the activity of 5-HT receptors mediating anorectic (via POMC/CART activation) and orexigenic (via NPY/AgRP activation) responses. In conditions of overweight and obesity the control of energy balance is clearly deregulated, and serotonergic modulation appears to make a significant contribution to weight gain. Fluoxetine (FLX), a selective serotonin reuptake inhibitor (SSRI) that increases 5-HT availability in the synaptic cleft may thus have potential effects on energy balance.

Serotonin transporter inhibition during neonatal period induces sex-dependent effects on mitochondrial bioenergetics in the rat brainstem.

The serotonin reuptake is mainly regulated by the serotonin transporters (SERTs), which are abundantly found in the raphe nuclei, located in the brainstem. Previous studies have shown that dysfunction in the SERT has been associated with several disorders, including depression and cardiovascular diseases. In this manuscript, we aimed to investigate how gender and the treatment with a serotonin selective reuptake inhibitor (SSRI) could affect mitochondrial bioenergetics and oxidative stress in the brainstem of male and female rats.

Neonatal treatment with fluoxetine improves mitochondrial respiration and reduces oxidative stress in liver of adult rats.

Recent studies have shown that exposure to fluoxetine treatment induces excessive production of ROS, and alters the antioxidant defense system in various tissues and cell types, mainly the liver. When fluoxetine is administered intraperitoneally, the drug rapidly reaches high concentrations in the liver, has potentially multiple toxic effects on energy metabolism in rat liver mitochondria. The aim of this study was to evaluate the effect of pharmacological treatment with fluoxetine during critical period for development on the mitochondrial bioenergetics and oxidative stress in liver of rat adult.

Protective effects of estrogen against cardiovascular disease mediated via oxidative stress in the brain.

During their reproductive years women produce significant levels of estrogens, predominantly in the form of estradiol, that are thought to play an important role in cardioprotection. Mechanisms underlying this action include both estrogen-mediated changes in gene expression, and post-transcriptional activation of protein signaling cascades in the heart and in neural centers controlling cardiovascular function, in particular, in the brainstem. There, specific neurons, especially those of the bulbar region play an important role in the neuronal control of the cardiovascular system because they control the outflow of sympathetic activity and parasympathetic activity as well as the reception of chemical and mechanical signals.

Neonatal fluoxetine exposure modulates serotonergic neurotransmission and disturb inhibitory action of serotonin on food intake.

The neurotransmitter serotonin (5-HT) acts as an important regulator of the critical neurodevelopmental processes and thus alterations in 5-HT signaling early promotes permanent structural and functional changes in brain. The selective serotonin reuptake inhibitors (SSRIs), as fluoxetine and citalopram, blocking serotonin transporter (SERT) at the presynaptic neuron, which regulates extracellular 5-HT levels. Evidence suggests that the exposure to SSRIs in the neurodevelopmental period may alters 5-HT signaling sensitivity on food intake control.

Neonatal SSRI exposure improves mitochondrial function and antioxidant defense in rat heart.

Protein restriction during prenatal, postnatal, or in both periods has a close relationship with subsequent development of cardiovascular disease in adulthood. Elevated brain levels of serotonin and its metabolites have been found in malnourished states. The aim in the present study was to investigate whether treatment with fluoxetine (Fx), a selective serotonin reuptake inhibitor, mimics the detrimental effect of low-protein diet during the perinatal period on the male rat heart.

Serotonin modulation in neonatal age does not impair cardiovascular physiology in adult female rats: Hemodynamics and oxidative stress analysis.

Aims: The present study investigates the effects of neonatal serotonin modulation in female rats on cardiac parameters related to hemodynamics and oxidative metabolism in the mature animal.

Main Methods: Female Wistar rat pups were administered daily subcutaneous injections of fluoxetine (Fx-treated group) or vehicle solution (Ct-group) from the 1st to 21st day of life. At 60days of age, animals from both groups were either used for cardiovascular evaluation or sacrificed for tissue collection for biochemical assays.

Effect of moderate exercise on peritoneal neutrophils from juvenile rats.

Previous studies showed that moderate exercise in adult rats enhances neutrophil function, although no studies were performed in juvenile rats. We evaluated the effects of moderate exercise on the neutrophil function in juvenile rats. Viability and neutrophils function were evaluated.

Effect of fluoxetine treatment on mitochondrial bioenergetics in central and peripheral rat tissues.

Recent investigations have focused on the mitochondrion as a direct drug target in the treatment of metabolic diseases (obesity, metabolic syndrome). Relatively few studies, however, have explicitly investigated whether drug therapies aimed at changing behavior by altering central nervous system (CNS) function affect mitochondrial bioenergetics, and none has explored their effect during early neonatal development. The present study was designed to evaluate the effects of chronic treatment of newborn male rats with the selective serotonin reuptake inhibitor fluoxetine on the mitochondrial bioenergetics of the hypothalamus and skeletal muscle during the critical nursing period of development.

The effect of maternal low-protein diet on the heart of adult offspring: role of mitochondria and oxidative stress.

Protein restriction during perinatal and early postnatal development is associated with a greater incidence of disease in the adult, such arterial hypertension. The aim in the present study was to investigate the effect of maternal low-protein diet on mitochondrial oxidative phosphorylation capacity, mitochondrial reactive oxygen species (ROS) formation, antioxidant levels (enzymatic and nonenzymatic), and oxidative stress levels on the heart of the adult offspring. Pregnant Wistar rats received either 17% casein (normal protein, NP) or 8% casein (low protein, LP) throughout pregnancy and lactation.

Fluoxetine treatment of rat neonates significantly reduces oxidative stress in the hippocampus and in behavioral indicators of anxiety later in postnatal life.

The brain, more than any other organ in the body, is vulnerable to oxidative stress damage, owing to its requirement for high levels of oxygenation. This is needed to fulfill its metabolic needs in the face of relatively low levels of protective antioxidants. Recent studies have suggested that oxidative stress is directly involved in the etiology of both eating and anxiety behavior.

Effects of early weaning on the circadian rhythm and behavioral satiety sequence in rats.

The objective of this work was to study the effect of early weaning on circadian rhythm and the behavioral satiety sequence in adult rats. Male Wistar rat pups were weaned for separation from the mother at 15 (D15), 21 (D21) and 30 (D30) days old. Body weight and food intake was measured every 30 days until pups were 150 days old.