A subiculum-hypothalamic pathway functions in dynamic threat detection and memory updating.

Animals need to detect threats, initiate defensive responses, and, in parallel, remember where the threat occurred to avoid the possibility of re-encountering it. By probing animals capable of detecting and avoiding a shock-related threatening location, we were able to reveal a septo-hippocampal-hypothalamic circuit that is also engaged in ethological threats, including predatory and social threats. Photometry analysis focusing on the dorsal premammillary nucleus (PMd), a critical interface of this circuit, showed that in freely tested animals, the nucleus appears ideal to work as a threat detector to sense dynamic changes under threatening conditions as the animal approaches and avoids the threatening source.

Control of feeding by a bottom-up midbrain-subthalamic pathway.

Investigative exploration and foraging leading to food consumption have vital importance, but are not well-understood. Since GABAergic inputs to the lateral and ventrolateral periaqueductal gray (l/vlPAG) control such behaviors, we dissected the role of vgat-expressing GABAergic l/vlPAG cells in exploration, foraging and hunting. Here, we show that in mice vgat l/vlPAG cells encode approach to food and consumption of both live prey and non-prey foods.

The Impact of Hydroxytyrosol on the Metallomic-Profile in an Animal Model of Alzheimer's Disease.

It is undeniable that as people get older, they become progressively more susceptible to neurodegenerative illnesses such as Alzheimer's disease (AD). Memory loss is a prominent symptom of this condition and can be exacerbated by uneven levels of certain metals. This study used inductively coupled plasma mass spectrometry (ICP-MS) to examine the levels of metals in the blood plasma, frontal cortex, and hippocampus of Wistar rats with AD induced by streptozotocin (STZ).

Consequences of oxygen deprivation on myelination and sex-dependent alterations.

Oxygen deprivation is one of the main causes of morbidity and mortality in newborns, occurring with a higher prevalence in preterm infants, reaching 20 % to 50 % mortality in newborns in the perinatal period. When they survive, 25 % exhibit neuropsychological pathologies, such as learning difficulties, epilepsy, and cerebral palsy. White matter injury is one of the main features found in oxygen deprivation injury, which can lead to long-term functional impairments, including cognitive delay and motor deficits.

The impact of antidepressants on human neurodevelopment: Brain organoids as experimental tools.

The use of antidepressants during pregnancy benefits the mother's well-being, but the effects of such substances on neurodevelopment remain poorly understood. Moreover, the consequences of early exposure to antidepressants may not be immediately apparent at birth. In utero exposure to selective serotonin reuptake inhibitors (SSRIs) has been related to developmental abnormalities, including a reduced white matter volume.

GABAergic CA1 neurons are more stable following context changes than glutamatergic cells.

The CA1 region of the hippocampus contains both glutamatergic pyramidal cells and GABAergic interneurons. Numerous reports have characterized glutamatergic CAMK2A cell activity, showing how these cells respond to environmental changes such as local cue rotation and context re-sizing. Additionally, the long-term stability of spatial encoding and turnover of these cells across days is also well-characterized.

Dorsal periaqueductal gray ensembles represent approach and avoidance states.

Animals must balance needs to approach threats for risk assessment and to avoid danger. The dorsal periaqueductal gray (dPAG) controls defensive behaviors, but it is unknown how it represents states associated with threat approach and avoidance. We identified a dPAG threatavoidance ensemble in mice that showed higher activity farther from threats such as the open arms of the elevated plus maze and a predator.

Impact of neonatal anoxia and hypothermic treatment on development and memory of rats.

Therapeutic hypothermia (TH) is well established as a standard treatment for term and near-term infants. However, therapeutic effects of hypothermia following neonatal anoxia in very premature babies remains inconclusive. The present rodent model of preterm neonatal anoxia has been shown to alter developmental milestones and hippocampal neurogenesis, and to disrupt spatial learning and memory in adulthood.

Evaluation of Possible Consequences of Zika Virus Infection in the Developing Nervous System.

The Zika virus (ZIKV) outbreak that occurred in the northeast of Brazil in 2015 led to alarming numbers of babies born with microcephaly in this region. Since then, several studies have evaluated the relationship between ZIKV infection and development of the malformation although the specific mechanistic interaction between ZIKV and human physiological processes that ultimately manifest as microcephaly remains debated. Importantly, most current studies did not consider the specificities of the biology and life cycle of ZIKV.

Functional Role of Intracellular Calcium Receptor Inositol 1,4,5-Trisphosphate Type 1 in Rat Hippocampus after Neonatal Anoxia.

Anoxia is one of the most prevalent causes of neonatal morbidity and mortality, especially in preterm neonates, constituting an important public health problem due to permanent neurological sequelae observed in patients. Oxygen deprivation triggers a series of simultaneous cascades, culminating in cell death mainly located in more vulnerable metabolic brain regions, such as the hippocampus. In the process of cell death by oxygen deprivation, cytosolic calcium plays crucial roles.

Determining the Roles of Inositol Trisphosphate Receptors in Neurodegeneration: Interdisciplinary Perspectives on a Complex Topic.

It is well known that calcium (Ca) is involved in the triggering of neuronal death. Ca cytosolic levels are regulated by Ca release from internal stores located in organelles, such as the endoplasmic reticulum. Indeed, Ca transit from distinct cell compartments follows complex dynamics that are mediated by specific receptors, notably inositol trisphosphate receptors (IP3Rs).

Interplay Between Exosomes, microRNAs and Toll-Like Receptors in Brain Disorders.

Extracellular vesicles (EVs), including exosomes, microvesicles and apoptotic bodies, participate in intercellular communication, and particularly, in paracrine and endocrine signalling. The EVs and their specific contents have been considered hallmarks of different diseases. It has been recently discovered that EVs can co-transport nucleic acids such as DNAs, ribosomal RNAs, circular RNAs (circRNAs), long noncoding RNAs (lnRNAs) and microRNAs (miRNAs).