Publications by authors named "Ana Sebastiao"

Article Synopsis
  • There is growing interest in using psychedelics like psilocybin to treat hard-to-manage psychiatric disorders, but little is known about how the experiences they create affect mood afterward.
  • In experiments with mice, it was found that psilocybin increased head-twitch responses more in females than in males, highlighting a sex difference in its effects.
  • Stress exposure during or after taking psilocybin impacted anxiety-like behavior in males, blocking its calming effects, while females only experienced a partial effect, suggesting that both sex and the context of the experience are important in understanding the drug's impact.
View Article and Find Full Text PDF

Despite the availability of new drugs on the clinics in recent years, drug-resistant epilepsy remains an unresolved challenge for healthcare, and one-third of epilepsy patients remain refractory to anti-seizure medications. Gene therapy in experimental models has emerged as effective treatment targeting specific neuronal populations in the epileptogenic focus. When combined with an external chemical activator using chemogenetics, it also becomes an "on-demand" treatment.

View Article and Find Full Text PDF

Unlabelled: Major Depressive Disorder (MDD) is a very complex disease, challenging to study and manage. The complexities of MDD require extensive research of its mechanisms to develop more effective therapeutic approaches. Crucial in the context of this disease is the role of brain-derived neurotrophic factor (BDNF) signaling pathway.

View Article and Find Full Text PDF

The pursuit of cosmetic ingredients with proven efficacy and safety that meet consumer needs drives the advancement of new products. Ascorbic acid (AA) is utilized in cosmetic products, predominantly for its potent antioxidant properties. Nonetheless, its instability compromises its efficacy.

View Article and Find Full Text PDF
Article Synopsis
  • Adenosine acts as a natural anticonvulsant through adenosine receptors (AR), but developing drugs that target these receptors has been challenging due to potential cardiac side effects.
  • The study examined the effects of a selective AR agonist called MRS5474 on excitatory and inhibitory signals in the hippocampus, using both rodent and human tissue samples.
  • Results showed that MRS5474 does not affect normal excitatory signals but enhances GABAergic currents in tissue from patients with epilepsy, suggesting its potential as a targeted antiseizure medication through activation of AR in epileptic conditions.
View Article and Find Full Text PDF

Alzheimer's disease (AD), the leading cause of dementia, is a multifactorial disease influenced by aging, genetics, and environmental factors. miRNAs are crucial regulators of gene expression and play significant roles in AD onset and progression. This exploratory study analyzed the expression levels of 28 genes and 5 miRNAs (miR-124-3p, miR-125b-5p, miR-21-5p, miR-146a-5p, and miR-155-5p) related to AD pathology and neuroimmune responses using RT-qPCR.

View Article and Find Full Text PDF
Article Synopsis
  • In Alzheimer's disease, amyloid beta (Aβ) triggers the cleavage of the TrkB-FL receptor, disrupting essential BDNF signaling that is crucial for neuron health and function.
  • Researchers found that TrkB-FL cleavage occurs early in the disease and worsens with increased pathology, using human samples and cerebrospinal fluid for their studies.
  • They developed a TAT-TrkB peptide that successfully prevents TrkB-FL cleavage, showing potential in improving cognitive function and synaptic issues in a mouse model of Alzheimer's, indicating it could be a safe and effective treatment option.
View Article and Find Full Text PDF

Neural stem cells (NSCs) reside in discrete regions of the adult mammalian brain where they can differentiate into neurons, astrocytes, and oligodendrocytes. Several studies suggest that mitochondria have a major role in regulating NSC fate. Here, we evaluated mitochondrial properties throughout NSC differentiation and in lineage-specific cells.

View Article and Find Full Text PDF

The immunomodulatory properties of β-glucans have sparked interest among various medical fields. As vaccine adjuvants, glucan particles offer additional advantages as antigen delivery systems. This study reported the immunomodulatory properties of glucan particles with different size and chemical composition.

View Article and Find Full Text PDF
Article Synopsis
  • The medial prefrontal cortex (mPFC) plays a crucial role in cognitive functions like working memory, and the astrocytic cannabinoid type 1 receptor (CB1R) affects calcium (Ca) signaling linked to neuronal activity.
  • Research shows that adenosine A1 and A2A receptors (AR, A2AR) can modulate CB1R function in mPFC astrocytes, influencing how calcium signaling operates in these cells.
  • The activation of CB1R enhances long-term potentiation (LTP) in the mPFC, which is regulated by A1 receptors, while in specific genetically modified mice lacking certain calcium responses, CB1R activation reduces LTP, suggesting a balanced
View Article and Find Full Text PDF

Epilepsy designates a group of chronic brain disorders, characterized by the recurrence of hypersynchronous, repetitive activity, of neuronal clusters. Epileptic seizures are the hallmark of epilepsy. The primary goal of epilepsy treatment is to eliminate seizures with minimal side effects.

View Article and Find Full Text PDF
Article Synopsis
  • Reductionistic research on depression has faced challenges due to limitations of animal models, particularly in understanding the role of neuroinflammation.
  • A study compared Wistar-Kyoto (WKY) rats, a model for depression, to Wistar (WS) controls, assessing both their behaviors linked to anxiety and depression and their brain levels of neuroinflammatory markers.
  • While WKY rats exhibited behaviors typical of depression, such as increased immobility and decreased social interaction, there were no significant differences in neuroinflammatory markers between the WKY and WS rats, suggesting locomotor deficits may obscure behavioral interpretations in these models.
View Article and Find Full Text PDF

The small-molecule drug, FTY720 (fingolimod), is a synthetic sphingosine 1-phosphate (S1P) analogue currently used to treat relapsing-remitting multiple sclerosis in both adults and children. FTY720 can cross the blood-brain barrier (BBB) and, over time, accumulate in lipid-rich areas of the central nervous system (CNS) by incorporating into phospholipid membranes. FTY720 has been shown to enhance cell membrane fluidity, which can modulate the functions of glial cells and neuronal populations involved in regulating behaviour.

View Article and Find Full Text PDF

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease, involving the selective degeneration of cortical upper synapses in the primary motor cortex (M1). Excitotoxicity in ALS occurs due to an imbalance between excitation and inhibition, closely linked to the loss/gain of astrocytic function. Using the ALS SOD1 mice, we investigated the astrocytic contribution for the electrophysiological alterations observed in the M1 of SOD1 mice, throughout disease progression.

View Article and Find Full Text PDF
Article Synopsis
  • * The study found that three weeks of social isolation resulted in notable behavioral changes in middle-aged mice, including increased depressive behaviors and anxiety, while younger mice showed resilience to these effects.
  • * Changes in the brain, specifically increased microglial activation and elevated pro-inflammatory cytokines, were observed in the isolated middle-aged mice, suggesting a link between inflammation and cognitive impairments caused by social isolation.
View Article and Find Full Text PDF

Astrocytes, the most abundant glial cells in the central nervous system (CNS), sense synaptic activity and respond through the release of gliotransmitters, a process mediated by intracellular Ca level changes and SNARE-dependent mechanisms. Ionotropic N-methyl-D-aspartate (NMDA) receptors, which are activated by glutamate along with D-serine or glycine, play a crucial role in learning, memory, and synaptic plasticity. However, the precise impact of astrocyte-released D-serine on neuronal modulation remains insufficiently characterized.

View Article and Find Full Text PDF

Objectives: to evaluate whether the colposcopic lesion size , age, kind of surgery, the status of the surgical margins and the expression of the p16 and Ki-67 immunomarkers are risk factors for persistence or recurrence of the lesion.

Methods: a cross-sectional, observational, retrospective study of patients submitted to cold knife conization (CKC) or the loop electrosurgical excision procedure for cervical intraepithelial neoplasia 2 or 3. The colposcopic lesion size, age, surgical method, involvement of the surgical margins, and p16/Ki-67 immunomarker expression were analyzed in relation to lesion persistence and recurrence.

View Article and Find Full Text PDF

Rett Syndrome is an X-linked neurodevelopmental disorder (RTT; OMIM#312750) associated to mutations. MeCP2 dysfunction is seen as one cause for the deficiencies found in brain-derived neurotrophic factor (BDNF) signaling, since BDNF is one of the genes under MeCP2 jurisdiction. BDNF signaling is also dependent on the proper function of the adenosinergic system.

View Article and Find Full Text PDF

Postnatal neurogenesis has been shown to rely on the endocannabinoid system. Here we aimed at unravelling the role of Cannabidivarin (CBDV), a non-psychoactive cannabinoid, with high affinity for the non-classical cannabinoid receptor TRPV1, on subventricular zone (SVZ) postnatal neurogenesis. Using the neurosphere assay, SVZ-derived neural stem/progenitor cells (NSPCs) were incubated with CBDV and/or 5'-Iodoresinferotoxin (TRPV1 antagonist), and their role on cell viability, proliferation, and differentiation were dissected.

View Article and Find Full Text PDF

Typical absence seizures (ASs) are brief periods of lack of consciousness, associated with 2.5-4 Hz spike-wave discharges (SWDs) in the EEG, which are highly prevalent in children and teenagers. The majority of probands in these young epileptic cohorts show neuropsychological comorbidities, including cognitive, memory and mood impairments, even after the seizures are pharmacologically controlled.

View Article and Find Full Text PDF

The accelerated development of antitumor immunotherapies in recent years has brought immunomodulation into the spotlight. These include immunotherapeutic treatments with dendritic cell (DC)-based vaccines which can elicit tumor-specific immune responses and prolong survival. However, this personalized treatment has several drawbacks, including being costly, labor-intensive, and time consuming.

View Article and Find Full Text PDF