Neuroinflammation: Molecular Mechanisms And Therapeutic Perspectives

MicroRNA-155 modulates methotrexate-induced spatial memory impairment by disruption of the blood-brain barrier integrity

AIM

Methotrexate (MTX) is a commonly used chemotherapy drug, yet its late neurotoxic side effects are gaining attention. The aim of the study was to evaluate the role of miR-155 in the pathogenesis of MTX-induced cognitive impairment, mainly focused on the interplay of blood-brain barrier (BBB) integrity and MTX toxicity.

MAIN METHODS

We use young rat model mimicking children leukemia treatment protocol, focusing on the systemic MTX effect on the central nervous system by intraperitoneal (IP) MTX injection. The cognitive function was evaluated by Morris Water Maze test and the BBB integrity was accessed by cortex permeability test. Tight junction proteins expression were also examined. Finally, we tested whether anti-miR155 pretreatment can reversed the MTX effect.

KEY FINDINGS

We found increased plasma miR-155 expression at 24 hr after IP MTX treatment. Besides, IP MTX resulted in impaired learning acquisition, which can be reversed by anti-miR155 treatment. Furthermore, brain cortex permeability and tight junction proteins were changed by IP MTX. miR-155 revealed its protective role in the current study for the development of MTX-induced cognitive impairment.

SIGNIFICANCE

IP MTX can induce significant cognitive impairment, which is related to the disruption of BBB integrity. miR-155 plays a vital role in the regulation of MTX-induced cognitive impairment, mainly through the maintenance of BBB integrity.

Resveratrol and Physical Activity: A Successful Combination for the Maintenance of Health and Wellbeing?

Physical exercise is an essential component of human health. In recent years, scientific research has focused on identifying natural compounds and formulating new supplements aimed at enhancing athletic performance, accelerating muscle recovery, and minimizing the damage caused by physical exertion. The use of antioxidants to counteract the formation of reactive oxygen species (ROS) following physical activity (PA) is already a widely adopted practice. Resveratrol (RES), a polyphenol belonging to the stilbene class, is well known for its potent antioxidant activity and anti-inflammatory effects primarily attributed to the activation of sirtuins. RES possesses multiple nutraceutical properties used for the prevention and treatment of inflammatory, cardiovascular, neoplastic, and infectious diseases, thus attracting attention to study its use in combination with physical exercise to promote well-being. Animal trials combining RES and PA have mainly reported improvements in muscle, energy, and cardiovascular functions. The data presented and discussed in this narrative review are from Pubmed, Scopus, and the Human Gene Database (search limited to 2011 to 2025 with the keywords RES, sirtuins, and physical activity altogether or in combination with each other). This review gathers several studies on RES focusing on its nutraceutical properties, epigenetic activities via sirtuins, and the potential benefits of combining RES with PA in maintaining health and well-being based on trials performed first in animals and later in humans. Human studies have been conducted on various populations, including active adults, sedentary individuals, patients with diseases, and elderly individuals. Some studies have confirmed the benefits of RES observed in animal experiments. However, in some cases, no substantial differences were found between RES supplementation and the control group. In conclusion, the benefits of RES on PA reported in the literature are still not fully evident, given the contrasting studies and the still limited number of trials, but both RES and PA are successful tools for the maintenance of health and wellbeing.

Dysregulation of miR-223, miR-146a, and miR-193a Expression Profile in Acute and Chronic Phases of Experimental Autoimmune Encephalomyelitis in C57BL/6 Mice

Multiple sclerosis (MS) is a chronic autoimmune disease with an unknown etiology. The purpose of this research was to assess miR-223, miR-146a, and miR-193a in acute and chronic phases of experimental autoimmune encephalomyelitis (EAE) mice to consider the possible role of these genes in the pathogenesis of MS. EAE induction was given by myelin oligodendrocyte glycoprotein peptide on female C57BL/6 mice. Clinical scores and other criteria were followed daily until day 21 for the acute group and day 77 for the chronic group. At the end of the course, inflammation and demyelination of the central nervous system (CNS) were assessed by histological analysis. MicroRNA expression levels were assessed by real-time PCR. EAE development attenuated in the chronic group, and histological analysis showed less infiltration and demyelination in the chronic group compared to the acute group. The upper expression of miR-223 is demonstrated in the acute phase of EAE. Moreover, the expression levels of miR-146a and miR-193a decreased in the chronic phase of EAE. MiR-223 showed a highly coordinated elevation in the acute phase both in vivo and in vitro. MiR-146a shares a pathway with miR-223 through effecting IL-6 expression. Further studies are needed to reveal their impact on EAE and possible applications as drug targets and biomarkers.

Reporting the anti-neuroinflammatory potential of selected spondias mombin flavonoids through network pharmacology and molecular dynamics simulations

Neuroinflammation plays a pivotal role in the development and progression of neurodegenerative diseases, with a complex interplay between immune responses and brain activity. Understanding this interaction is crucial for identifying therapeutic targets and developing effective treatments. This study aimed to explore the neuroprotective properties of flavonoid compounds from Spondias mombin via the modulation of neuroinflammatory pathway using a comprehensive in-silico approach, including network pharmacology, molecular docking, and dynamic simulations. Active flavonoid ingredients from S. mombin were identified, and their potential protein targets were predicted through Network Pharmacology. Molecular docking was conducted to determine the binding affinities of these compounds against targets obtained from network pharmacology, prioritizing docking scores ≥ - 8.0 kcal/mol. Molecular dynamic simulations (MDS) assessed the stability and interaction profiles of these ligand-protein complexes. The docking study highlighted ≥ - 8.0 kcal/mol for the ligands (catechin and epicatechin) against FYN kinase as a significant target. However, these compounds failed the blood-brain barrier (BBB) permeability test. MDS confirmed the stability of catechin and the reference ligand at the FYN kinase active site, with notable interactions involving hydrogen bonds, hydrophobic contacts, and water bridges. GLU54 emerged as a key residue in the catechin-FYN complex stability due to its prolonged hydrogen bond interaction. The findings underscore the potential of S. mombin flavonoids as therapeutic agents against neuroinflammation, though optimization and nanotechnology-based delivery methods are suggested to enhance drug efficacy and overcome BBB limitations.

Graphical abstract

Suicide, neuroinflammation and other physiological alterations

Suicide is considered one of the major public health problems worldwide, being the second leading cause of death in the 15-29 age group. It is estimated that every 40s someone in the world commits suicide. The social taboo surrounding this phenomenon as well as the fact that suicide prevention measures currently fail to avoid deaths from this cause, means that more research is needed to understand its mechanisms. The present narrative review on suicide tries to point out several important aspects, such as risk factors or the dynamics of suicide, as well as the current findings in the field of physiology that could offer advances in the understanding of suicide. Subjective measures of risk such as scales and questionnaires are not effective alone, whereas the objective measures can be addressed from physiology. Thus, an increased neuroinflammation in people who take their own lives has been found, with an increase in inflammatory markers such as interleukin-6 and other cytokines in plasma or cerebrospinal fluid. Also, the hyperactivity of the hypothalamic-pituitary-adrenal axis and a decrease in serotonin or in vitamin D levels seems to also be involved. In conclusion, this review could help to understand which factors can trigger an increased risk of dying by suicide, as well as pointing out those alterations that occur in the body when someone attempt to commit suicide or succeeds in taking their own life. There is a need for more multidisciplinary approaches that address suicide to help to raise awareness of the relevance of this problem that causes the death of thousands of people every year.

Enviromental endocrine disruptor risks in the central nervous system: Neurotoxic effects of PFOS and glyphosate

Endocrine disruptors (EDs) pose significant risks to human and environmental health, with potential implications for neurotoxicity. This study investigates the synergistic neurotoxic effects of perfluorooctane sulfonate (PFOS) and glyphosate (GLY), two ubiquitous EDs, using SHSY5Y neuronal and C6 astrocytic cell lines. While individual exposures to PFOS and glyphosate at non-toxic concentrations did not induce significant changes, their combination resulted in a marked increase in oxidative stress and neuroinflammatory responses. Specifically, the co-exposure led to elevated levels of interleukin-6, tumor necrosis factor alpha, and interferon gamma, along with reduced interleukin-10 expression, indicative of heightened neuroinflammatory processes. These findings underscore the importance of considering the synergistic interactions of EDs in assessing neurotoxic risks and highlight the urgent need for further research to mitigate the adverse effects of these compounds on neurological health.

Gut-Brain Axis: Focus on Sex Differences in Neuroinflammation

In recent years, there has been a growing interest in the concept of the "gut-brain axis". In addition to well-studied diseases associated with an imbalance in gut microbiota, such as cancer, chronic inflammation, and cardiovascular diseases, research is now exploring the potential role of gut microbial dysbiosis in the onset and development of brain-related diseases. When the function of the intestinal barrier is altered by dysbiosis, the aberrant immune system response interacts with the nervous system, leading to a state of "neuroinflammation". The gut microbiota-brain axis is mediated by inflammatory and immunological mechanisms, neurotransmitters, and neuroendocrine pathways. This narrative review aims to illustrate the molecular basis of neuroinflammation and elaborate on the concept of the gut-brain axis by virtue of analyzing the various metabolites produced by the gut microbiome and how they might impact the nervous system. Additionally, the current review will highlight how sex influences these molecular mechanisms. In fact, sex hormones impact the brain-gut microbiota axis at different levels, such as the central nervous system, the enteric nervous one, and enteroendocrine cells. A deeper understanding of the gut-brain axis in human health and disease is crucial to guide diagnoses, treatments, and preventive interventions.

PLASTAMINATION: Outcomes on the Central Nervous System and Reproduction

BACKGROUND

Environmental exposures to non-biodegradable and biodegradable plastics are unavoidable. Microplastics (MPs) and nanoplastics (NPs) from the manufacturing of plastics (primary sources) and the degradation of plastic waste (secondary sources) can enter the food chain directly or indirectly and, passing biological barriers, could target both the brain and the gonads. Hence, the worldwide diffusion of environmental plastic contamination (PLASTAMINATION) in daily life may represent a possible and potentially serious risk to human health.

OBJECTIVE

This review provides an overview of the effects of non-biodegradable and the more recently introduced biodegradable MPs and NPs on the brain and brain-dependent reproductive functions, summarizing the molecular mechanisms and outcomes on nervous and reproductive organs. Data from in vitro, ex vivo, non-mammalian and mammalian animal models and epidemiological studies have been reviewed and discussed.

RESULTS

MPs and NPs from non-biodegradable plastics affect organs, tissues and cells from sensitive systems such as the brain and reproductive organs. Both MPs and NPs induce oxidative stress, chronic inflammation, energy metabolism disorders, mitochondrial dysfunction and cytotoxicity, which in turn are responsible for neuroinflammation, dysregulation of synaptic functions, metabolic dysbiosis, poor gamete quality, and neuronal and reproductive toxicity. In spite of this mechanistic knowledge gained from studies of non-biodegradable plastics, relatively little is known about the adverse effects or molecular mechanisms of MPs and NPs from biodegradable plastics.

CONCLUSION

The neurological and reproductive health risks of MPs/NPs exposure warrant serious consideration, and further studies on biodegradable plastics are recommended.

Molecular Advances on Cannabinoid and Endocannabinoid Research

Since ancient times, cannabis has been used for recreational and medical purposes [...].

Stress Reduction Potential in Mice Ingesting DNA from Salmon Milt

The functionality of food-derived nucleotides is revealed when nucleotide components are ingested in emergency situations, such as during stress loading, though it is difficult to elucidate the physiological function of dietary nucleotide supplementation. Using a stress load experimental system utilizing territoriality among male mice, we evaluated whether DNA sodium salt derived from salmon milt (DNA-Na) has stress-relieving effects. It was found that stress was reduced in mice fed a diet containing a 1% concentration of DNA-Na, but this was insignificant for yeast-derived RNA. Next, we attempted to elucidate the anti-stress effects of DNA-Na using another experimental system, in which mice were subjected to chronic crowding stress associated with aging: six mice in a cage were kept until they were 7 months of age, resulting in overcrowding. We compared these older mice with 2-month-old mice that were kept in groups for only one month. The results show that the expression of genes associated with hippocampal inflammation was increased in the older mice, whereas the expression of these genes was suppressed in the DNA-Na-fed group. This suggests that dietary DNA intake may suppress inflammation in the brain caused by stress, which increases with age.

Molecular and Epigenetic Aspects of Opioid Receptors in Drug Addiction and Pain Management in Sport

Opioids are substances derived from opium (natural opioids). In its raw state, opium is a gummy latex extracted from Papaver somniferum. The use of opioids and their negative health consequences among people who use drugs have been studied. Today, opioids are still the most commonly used and effective analgesic treatments for severe pain, but their use and abuse causes detrimental side effects for health, including addiction, thus impacting the user's quality of life and causing overdose. The mesocorticolimbic dopaminergic circuitry represents the brain circuit mediating both natural rewards and the rewarding aspects of nearly all drugs of abuse, including opioids. Hence, understanding how opioids affect the function of dopaminergic circuitry may be useful for better knowledge of the process and to develop effective therapeutic strategies in addiction. The aim of this review was to summarize the main features of opioids and opioid receptors and focus on the molecular and upcoming epigenetic mechanisms leading to opioid addiction. Since synthetic opioids can be effective for pain management, their ability to induce addiction in athletes, with the risk of incurring doping, is also discussed.