Publications by authors named "Rudimar Frozza"

Infection by SARS-CoV-2 is associated with uncontrolled inflammatory response during COVID-19 severe disease, in which monocytes are one of the main sources of pro-inflammatory mediators leading to acute respiratory distress syndrome. Extracellular vesicles (EVs) from different cells play important roles during SARS-CoV-2 infection, but investigations describing the involvement of EVs from primary human monocyte-derived macrophages (MDM) on the regulation of this infection are not available. Here, we describe the effects of EVs released by MDM stimulated with the neuropeptides VIP and PACAP on SARS-CoV-2-infected monocytes.

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Glioblastoma (GBM) stands as the most aggressive and lethal among the main types of primary brain tumors. It exhibits malignant growth, infiltrating the brain tissue, and displaying resistance toward treatment. GBM is a complex disease characterized by high degrees of heterogeneity.

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A substantial body of evidence supports that the gut microbiota plays a pivotal role in the regulation of metabolic, endocrine and immune functions. In recent years, there has been growing recognition of the involvement of the gut microbiota in the modulation of multiple neurochemical pathways through the highly interconnected gut-brain axis. Although amazing scientific breakthroughs over the last few years have expanded our knowledge on the communication between microbes and their hosts, the underpinnings of microbiota-gut-brain crosstalk remain to be determined.

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β-Cyclodextrin (β-CD) is being considered a promising therapy for Niemann-Pick C (NPC) disease because of its ability to mobilise the entrapped cholesterol from lysosomes, however, a major limitation is its inability to cross the blood-brain barrier (BBB) and address the central nervous system (CNS) manifestations of the disease. Considering this, we aimed to design nanoparticles able to cross the BBB and deliver β-CD into the CNS lysosomes. The physicochemical characteristics of β-CD-loaded nanoparticles were evaluated by dynamic light scattering, small-angle X-ray scattering, and cryogenic transmission electron microscopy.

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Defective brain hormonal signaling has been associated with Alzheimer's disease (AD), a disorder characterized by synapse and memory failure. Irisin is an exercise-induced myokine released on cleavage of the membrane-bound precursor protein fibronectin type III domain-containing protein 5 (FNDC5), also expressed in the hippocampus. Here we show that FNDC5/irisin levels are reduced in AD hippocampi and cerebrospinal fluid, and in experimental AD models.

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Lysosomal Storage Disorders (LSDs) are characterized by an abnormal accumulation of substrates within the lysosome and comprise more than 50 genetic disorders with a frequency of 1:5000 live births. Nanotechnology may be a promising way to circumvent the drawbacks of the current therapies for lysosomal diseases. The blood circulation time and bioavailability of the enzymes or drugs could be improved by inserting them in nanocarriers, which could decrease and/or avoid the need of frequent intravenous infusions along with the minimization or elimination of associated immunogenic responses.

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Inflammation is the principal response invoked by the body to address injuries. Despite inflammation constituting a crucial component of tissue repair, it is well known that unchecked or chronic inflammation becomes deleterious, leading to progressive tissue damage. Studies over the past years focused on foods rich in polyphenols with anti-inflammatory and immunomodulatory properties, since inflammation was recognized to play a central role in several diseases.

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Clinical trials have extensively failed to find effective treatments for Alzheimer's disease (AD) so far. Even after decades of AD research, there are still limited options for treating dementia. Mounting evidence has indicated that AD patients develop central and peripheral metabolic dysfunction, and the underpinnings of such events have recently begun to emerge.

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Alzheimer's disease (AD), the most common form of dementia in late life, will become even more prevalent by midcentury, constituting a major global health concern with huge implications for individuals and society. Despite scientific breakthroughs during the past decades that have expanded our knowledge on the cellular and molecular bases of AD, therapies that effectively halt disease progression are still lacking, and focused efforts are needed to address this public health challenge. Because AD is classically recognized as a disease of memory, studies have mainly focused on investigating memory-associated brain defects.

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Sepsis survivors frequently develop late cognitive impairment. Because little is known on the mechanisms of post-septic memory deficits, there are no current effective approaches to prevent or treat such symptoms. Here, we subjected mice to severe sepsis induced by cecal ligation and puncture (CLP) and evaluated the sepsis-surviving animals in the open field, novel object recognition (NOR), and step-down inhibitory avoidance (IA) task at different times after surgery.

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Alzheimer's disease (AD) is associated with peripheral metabolic disorders. Clinical/epidemiological data indicate increased risk of diabetes in AD patients. Here, we show that intracerebroventricular infusion of AD-associated Aβ oligomers (AβOs) in mice triggered peripheral glucose intolerance, a phenomenon further verified in two transgenic mouse models of AD.

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Berberine is an alkaloid derived from herb the Berberis sp. and has long-term use in Oriental medicine. Studies along the years have demonstrated its beneficial effect in various neurodegenerative and neuropsychiatric disorders.

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Alzheimer's disease (AD) and type 2 diabetes appear to share similar pathogenic mechanisms. dsRNA-dependent protein kinase (PKR) underlies peripheral insulin resistance in metabolic disorders. PKR phosphorylates eukaryotic translation initiation factor 2α (eIF2α-P), and AD brains exhibit elevated phospho-PKR and eIF2α-P levels.

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Resveratrol, a natural polyphenolic compound, has attracted considerable interest for its anti-inflammatory and neuroprotective properties. However, the biological effects of resveratrol appear strongly limited because it is photosensitive, easily oxidized, and has unfavorable pharmacokinetics. The present study aimed to elucidate the effect of resveratrol on Abeta-triggered neuroinflammation by comparing the effects of free resveratrol (RSV) treatment with those of treatment with resveratrol-loaded lipid-core nanocapsules (RSV-LNC).

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Background/aim: Despite recent progress in glioblastoma treatment, prognosis is still poor. Monastrol is a kinesin spindle protein (KSP) inhibitor and anticancer effects for this molecule have been reported. Here we describe the effect of LaSOM 65, a monastrol derivated compound, against glioma cell lines.

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Alzheimer's disease (AD), a neurodegenerative disorder exhibiting progressive loss of memory and cognitive functions, is characterized by the presence of neuritic plaques composed of neurofibrillary tangles and β-amyloid (Aβ) peptide. Drug delivery to the brain still remains highly challenging for the treatment of AD. Several studies have been shown that curcumin is associated with anti-amyloidogenic properties, but therapeutic application of its beneficial effects is limited.

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Objective: Accumulating evidence indicates that curcumin potently protects against beta-amyloid (Abeta) due to its oxygen free radicals scavenging and anti-inflammatory properties. However, cellular mechanisms that may underlie the neuroprotective effect of curcumin in Abeta-induced toxicity are not fully understood yet. The present study was undertaken to investigate the mechanisms involved in neuroprotective effects of curcumin, particularly involving Wnt/beta-catenin and PI3K pathways.

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The development of novel therapeutic strategies to treat gliomas remains critical as a result of the poor prognoses, inef-. ficient therapies and recurrence associated with these tumors. In this context, biodegradable nanoparticles are emerging as efficient drug delivery systems for the treatment of difficult-to-treat diseases such as brain tumors.

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Despite recent advances in radiotherapy, chemotherapy, and surgical techniques, glioblastoma multiforme (GBM) prognosis remains dismal. There is an urgent need for new therapeutic strategies. Nanoparticles of biodegradable polymers for anticancer drug delivery have attracted intense interest in recent years because they can provide sustained, controlled, and targeted delivery.

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Alzheimer's disease (AD), a neurodegenerative disorder exhibiting a gradual decline in cognitive function, is characterized by the presence of neuritic plaques composed of neurofibrillary tangles and amyloid-β (Aβ) peptide. Available drugs for AD therapy have small effect sizes and do not alter disease progression. Several studies have been shown that resveratrol is associated with anti-amyloidogenic properties, but therapeutic application of its beneficial effects is limited.

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Neuroinflammation, characterized by the accumulation of activated microglia and reactive astrocytes, is believed to modulate the development and/or progression of Alzheimer's disease (AD). Epidemiological studies suggesting that nonsteroidal anti-inflammatory drugs decrease the risk of developing AD have encouraged further studies elucidating the role of inflammation in AD. Nanoparticles have become an important focus of neurotherapeutic research because they are an especially effective form of drug delivery.

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The effect of Aβ25-35 peptide, in its fibrillar and non-fibrillar forms, on ganglioside expression in organotypic hippocampal slice cultures was investigated. Gangliosides were endogenously labeled with D-[1-C(14)] galactose and results showed that Aβ25-35 affected ganglioside expression, depending on the peptide aggregation state, that is, fibrillar Aβ25-35 caused an increase in GM3 labeling and a reduction in GD1b labeling, whereas the non-fibrillar form was able to enhance GM1 expression. Interestingly, GM1 exhibited a neuroprotective effect in this organotypic model, since pre-treatment of the hippocampal slices with GM1 10 μM was able to prevent the toxicity triggered by the fibrillar Aβ25-35, when measured by propidium iodide uptake protocol.

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Several studies have reported that orally ingested trans-resveratrol is extensively metabolized in the enterocyte before it enters the blood and target organs. Additionally, trans-resveratrol is photosensitive, easily oxidized and presents unfavorable pharmacokinetics. Therefore, it is of great interest to stabilize trans-resveratrol in order to preserve its biological activities and to improve its bioavailability in the brain.

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This study was undertaken to evaluate the effects of chronic variate stress and lithium treatment on glutamatergic activity and neuronal vulnerability of rat hippocampus. Male Wistar rats were simultaneously treated with lithium and submitted to a chronic variate stress protocol during 40 days, and afterwards the hippocampal glutamatergic uptake and release, measured in slices and synaptosomes, were evaluated. We observed an increased synaptosomal [(3)H]glutamate uptake and an increase in [(3)H]glutamate stimulated release in hippocampus of lithium-treated rats.

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Targeted treatment of diseases of the central nervous system remains problematic due to the complex pathogenesis of these disorders and the difficulty in drug delivery. Here we investigate the neuroprotective effect of indomethacin-loaded nanocapsules (IndOH-NC) in an in vitro model of ischemia. For this purpose we used organotypic hippocampal cultures exposed to oxygen-glucose deprivation (OGD).

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