Esteban Aliaga

Universidad Católica del Maule | UCM · Escuela de Tecnología Médica

Stress-related disorders display differences at multiple levels according to sex. While most studies have been conducted in male rodents, less is known about comparable outcomes in females. In this study, we found that the chronic restraint stress model (2.5 h/day for 14 days) triggers different somatic responses in male and female adult rats. Chro...

We explored sex-biased effects of the primary stress glucocorticoid hormone corticosterone on the miRNA expression profile in the rat hippocampus. Adult adrenalectomized (ADX) female and male rats received a single corticosterone (10 mg/kg) or vehicle injection, and after 6 h, hippocampi were collected for miRNA, mRNA, and Western blot analyses. mi...

Sex differences in the brain have prompted many researchers to investigate the underlying molecular actors, such as the glucocorticoid receptor (GR). This nuclear receptor controls gene expression, including microRNAs (miRNAs), in non-neuronal cells. Here, we investigated sex-biased effects of GR on hippocampal miRNA expression and neuronal morphol...

Autism spectrum disorder (ASD) is a neurodevelopmental alteration characterized by social/communicative deficits, repetitive/stereotyped movements, and restricted/obsessive interests. However, there is not much information about whether movement alterations in ASD comprise modifications at the basic kinematic level, such as trajectory and velocity,...

Several lines of evidence suggest that antidepressant drugs may act by modulating neuroplasticity pathways in key brain areas like the hippocampus. We have reported that chronic treatment with fasudil, a Rho-associated protein kinase inhibitor, prevents both chronic stress-induced depressive-like behavior and morphological changes in CA1 area. Here...

Autism is a neurodevelopmental disorder characterized by a deep deficit in language and social interaction, accompanied by restricted, stereotyped and repetitive behaviors. The use of genetic autism animal models has revealed that the alteration of the mechanisms controlling the formation and maturation of neural circuits are points of convergence...

Several studies have shown that a single exposure to stress may improve or impair learning and memory processes, depending on the timing in which the stress event occurs with relation to the acquisition phase. However, to date there is no information about the molecular changes that occur at the synapse during the stress-induced memory modification...

Studies conducted in rodents subjected to chronic stress and some observations in humans after psychosocial stress, have allowed to establish a link between stress and the susceptibility to many complex diseases, including mood disorders. The studies in rodents have revealed that chronic exposure to stress negatively affects synaptic plasticity by...

Serotonin acts through its receptors (5-HTRs) to shape brain networks during development and modulates essential functions in mature brain. The 5-HT1AR is mainly located at soma of hippocampal neurons early during brain development and its expression gradually shifts to dendrites during postnatal development. The 5-HT7R expressed early during hippo...

Previous studies in rats have demonstrated that chronic restraint stress triggers anhedonia, depressive-like behaviors, anxiety and a reduction in dendritic spine density in hippocampal neurons. In this study, we compared the effect of repeated stress on the expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl-D-as...

Background: Dendritic arbor simplification and dendritic spine loss in the hippocampus -a limbic structure implicated in mood disorders- are assumed to contribute to symptoms of depression. These morphological changes imply changes in dendritic cytoskeleton. Rho GTPases are regulators of actin dynamics through their effector Rho kinase (ROCK). We...

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder characterized by deficits in social communication and social interaction, and repetitive and stereotypical patterns of behavior. Previously, a common physiopathological pathway, involving the control of synaptic protein synthesis, was proposed as a convergence point in AS...

Chronic stress promotes cognitive impairment and dendritic spine loss in hippocampal neurons. In this animal model of depression, spine loss probably involves a weakening of the interaction between pre- and postsynaptic cell adhesion molecules, such as N-cadherin, followed by disruption of the cytoskeleton. N-cadherin, in concert with catenin, stab...

Background Central nervous system (CNS) development and physiopathology are greatly affected by environmental stimuli. The intestinal barrier restricts the entrance of toxins, pathogens, and antigens while modulating the expression of various neuroactive compounds. The existence of a rich gut-to-brain communication raises the possibility that intes...

Adult hypothyroidism is a highly prevalent condition that impairs processes, such as learning and memory. Even though tetra-iodothyronine (T(4)) treatment can overcome the hypothyroidism in the majority of cases, it cannot fully recover the patient's learning capacity and memory. In this work, we analyzed the cellular and molecular changes in the a...

ABSTRACT Background: Adult hypothyroidism is a highly prevalent condition that impairs processes, such as learning and memory. Even though T4 treatment can overcome the hypothyroidism in the majority of cases, it cannot fully recover the patient's learning capacity and memory. In this work we analyzed the cellular and molecular changes in the adult...

Beta-amyloid (Abeta) deposition is one important pathological hallmark in Alzheimer's disease (AD). However, low levels of Abeta may modify critical endogenous protection systems before neurodegeneration occurs. We examined the time-course effect of sublethal concentrations of Abeta on total BDNF (panBDNF), BDNF transcripts (I, II, IV and VI), trkB...

During development, regulation of the strength of synaptic transmission plays a central role in the formation of mammalian brain circuitries. In taiep rat, a neurological mutant with severe reactive astrogliosis and demyelination, we have described alterations in the synaptic transmission in central neurons, characterized by asynchronous excitatory...

We investigated subcellular localization of total brain-derived neurotrophic factor (BDNF) mRNA (panBDNF) and its different 5' exon-specific transcripts in cultured hypothalamic neurons. Non-isotopic in situ hybridization (DIG-labeled exon-specific riboprobes) associated with immunocytochemical MAP2 or GFAP labeling was used for detection. We found...

The decline observed during aging involves multiple factors that influence several systems. It is the case for learning and memory processes which are severely reduced with aging. It is admitted that these cognitive effects result from impaired neuronal plasticity, which is altered in normal aging but mainly in Alzheimer disease. Neurotrophins and...

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family involved in plasticity and neuroprotective processes. In recent years, we have reported the presence of BDNF mRNA in the supraoptic nucleus (SON) as well its sensitivity to osmotic stress. The rat SON is a relatively homogenous nucleus mainly consisting of magnocellular...

Dopaminergic nigrostriatal neurons may be considered as bipolar functional entities since they are endowed with the ability to synthesize, store and release the transmitter dopamine (DA) at the somatodendritic level in the substantia nigra (SN). Such dendritic DA release seems to be distinct from the transmitter release occurring at the axon termin...

We have shown that osmotic stress increases brain-derived neurotrophic factor (BDNF) mRNA in the supraoptic nucleus and that this increase seems to be determined by the high expression of transcripts containing exon I. The paraventricular nucleus is another hypothalamic neuronal subset where BDNF mRNA is also sensitive to osmotic stress stimulation...

By using non-isostopic in situ hybridization we have demonstrated a transient increase of BDNF mRNA in the lateral subregion of the substantia nigra pars reticulata 1 week after intrastriatal application of 6-OH-DA. These changes correlate with a partial reduction of dopamine (DA) content in the striatum but with a normal tyrosine hydroxylase immun...

By using in situ hybridization, we have demonstrated that kainic acid (KA) administration decreases brain-derived neurotrophic factor (BDNF) mRNA expression in the substantia nigra pars compacta of adult rat. In addition, RT-PCR analysis indicated that transcripts derived from exons 1a and 1c of the BDNF gene were strongly decreased after KA treatm...

Brain-derived neurotrophic factor (BDNF) enhances survival and protects dopaminergic neurons from neurotoxicity. We have examined in primary cultures of fetal mesencephalic neurons the expression of BDNF transcripts and its regulation by glutamate receptor agonists. RT-PCR experiments showed in these cultures the expression of mRNA encoding for neu...

Induced release of endogenous dopamine and noradrenaline from coronal slices containing the striatum and the bed nucleus of the stria terminalis, respectively, was studied by means of in vitro microdialysis. A Ca(+2)-dependent and reserpine-sensitive K(+)-induced release of catecholamines was detected in both nuclei. We confirmed that N-methyl-D-as...