central nervous system

An incapacitating chronic inflammatory neurodegenerative illness, known as multiple sclerosis (MS), is characterized by lymphocyte infiltration into the central nervous system. We aimed to identify specific miRNAs whose altered expression correlates with MS diagnosis and therapy selection, which could be biomarkers for these aspects of the disease. The GSE21079 dataset was obtained for this study using Geoquery version 2.50.5 from the Gene Expression Omnibus database. The miRNAs exhibiting the highest variance were selected, and a miRNA-miRNA interaction network was constructed through a Bayesian network utilizing the bnlearn R package (version 4.7.1). The adjacency matrix generated from the learned network was subsequently analyzed in the Cytoscape environment. For the workbench lab, whole blood samples were collected from the MS Research Center and Al-Zahra Hospital in Isfahan, Iran, between June 2019 and October 2019. RNA extraction was conducted in the laboratory at Isfahan University. Real-time PCR (RT-PCR) was employed to validate the expression changes of the candidate mirRNAs (hsa-miR-520d-3p, hsa-miR-449a). The results were analyzed using REST 2009 software. The Notch1 signaling pathway was targeted by hsa-miR-520d-3p and hsa-miR-449a in MS patients, which led to downregulation of critical genes, such as LIM and SH3 protein 1 (LASP1), Tubulin Alpha1c (TUBA1C), and S100 calcium binding protein A6 (S100A6). Furthermore, the results from RT-PCR among 50 whole blood samples, comprising 30 cases of MS and 20 control cases, indicated that the expression levels of miRNA in patients with MS exhibited a statistically significant difference compared to those in healthy individuals, with values of 0.324 for hsa-miR-520d-3p and 0.075 for hsa-miR-449a. These values correspond to a downregulation of 3.1-fold and 13.3-fold, respectively. The findings indicate that MS patients have lower expression levels of hsa-miR-520d-3p and hsa-miR-449a.

Insomnia or sleep disorders refer to conditions involving insufficient sleep, difficulty falling asleep, or sudden awakenings. These issues can be unpleasant for some individuals and may affect their daily performance. While there are various causes of insomnia, scientific research continues to investigate the body's need for sleep and its underlying causes. This study aims to evaluate the effects of herbal remedies on sleep improvement and insomnia treatment. The mechanisms influencing insomnia and the ways in which Iranian medicinal plants affect sleep quality are analyzed and discussed.

In this review, key terms such as herbal remedies, traditional medicine, native Iran, insomnia, and sleep treatment were utilized. Relevant articles were sourced from well-established academic databases such as PubMed, Google Scholar, Scopus, and Web of Science. Additionally, specialized resources, including reference books, encyclopedias, and online materials, were used to gather information. All articles and sources were thoroughly examined to identify the medicinal plants used in traditional Iranian medicine for improving sleep.

Traditional Iranian medicine offers various herbal solutions for sleep improvement and insomnia, including medicinal plants such as saffron, thyme, lavender, guava, sage, rosemary, eucalyptus leaves, mint, ginger, lemon balm, cinnamon, chamomile, passionflower, jujube, hops, violets, borage, bitter orange, milk thistle, wild lettuce, green tea, and wormwood. These plants are among the most commonly used herbs in Iranian traditional medicine for addressing sleep disorders.

The results of this review highlight that herbal remedies are recognized as a safe and natural treatment for insomnia and improving sleep quality. These plants primarily act through the regulation of the central nervous system, reduction of anxiety and stress, and the enhancement of melatonin production.

Dear Editor, Multiple sclerosis (MS) is a chronic condition affecting the central nervous system (CNS). MS is associated with various comorbidities, including cardiovascular diseases, neurological disturbances, stroke, hypertension, and metabolic disorders.[1] stroke characterized by malperfusion of CNS tissue, is among the significant comorbidities observed in MS patients.[2,3] We undertook a study aimed at determining the prevalence of stroke among pwMS in Isfahan, Iran.

Rabies is a severe public health issue, particularly in areas with limited vaccination rates. Despite significant progress in comprehending the illness and creating preventative methods, rabies poses a significant public health problem. Glucocorticoids like dexamethasone effectively reduce inflammation and immunomodulation, but their effects on viral infections, with specific reference to the central nervous system (CNS), are complex and unclear. This study focuses on the apoptosis of brain cells in NMRI (Naval Medical Research Institute) mice infected with a viral infection. Infected mice were randomly assigned to four groups (n=10 per group): a control group, a negative control group treated with dexamethasone, an untreated positive control group containing viral components, and a test group expressing viral components and treated with dexamethasone. FAT results showed that the virus components were present in the brain tissue of NMRI mice; intense positive staining was observed. AKT, BAX, and BCL2 expression were significantly lowered in rat brain tissue compared to untreated mice (p<0.05). This study demonstrates the significant change effected by dexamethasone in the pathway of brain cell death in mouse brain tissue. The findings of this study could have significant implications for the risk-benefit ratio of dexamethasone therapy in viral CNS infections and guide possibly more effective and safer treatment strategies in such conditions.

Although viral etiology of central nervous system (CNS) infections such as meningitis and encephalitis are investigated widely worldwide, it remains to be declared under the COVID-19 pandemic.

The focus of this study was to examine the etiology of viral CNS infections in patients hospitalized in a single referral hospital during the outbreak in Iran.

We retrospectively collected the cerebrospinal fluid (CSF) samples and reviewed the medical records of patients hospitalized with suspected viral CNS infection in Shiraz, a large city in southern Iran, from April 2021 to May 2022. One hundred sixty-six CSF samples were tested primarily for detection of HSV-1 and -2 and retrospectively analyzed by primers polymerase chain reaction (PCR) targeted to coronavirus 2 (SARS-CoV-2), human herpesviruses1 to 6 (HHV-1 to 6), polyomaviruses JC, and enteroviruses (EV).

Of the total CSF samples analyzed by PCR, 22 (13.3%) were positive for only one viral pathogen, and just one (0.6%) sample was detected with multiple viruses (HSV-1 and CMV). The SARS-CoV-2 (6 cases) was the second most common viral etiology just after Herpes simplex virus-1 (HSV-1) 6.6% (11 cases). Other detected viruses were CMV for 1.8% (3 cases), VZV for 1.2% (2 cases), and JC for 0.6% (1 case) of the cases.

This study highlights the prevalence of viral pathogens in CSF samples from patients with suspected meningitis at Namazi Teaching Hospital. Notably, HSV-1 was the most common virus detected, followed by SARS-CoV-2. These findings underscore the importance of viral testing in the diagnosis and management of meningitis.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a potential trigger for central nervous system (CNS) autoimmune disorders. The most common type of spinal cord pathology following novel coronavirus infection is immune-mediated/autoimmune transverse myelitis (TM); however, there are also rare forms of spinal cord pathology ‒ tract-specific myelitis ‒ previously considered as non-autoimmune-originated. The current study includes case series of 5 patients with a rare type of myelitis with predominant involvement of the dorsal and lateral columns following coronavirus disease 2019 (COVID-19). We aimed to analyze cytokines parameters in cerebrospinal fluid (CSF) of affected patients. In order to support the autoimmune origin of the disease, CSF cytokine profiles were compared to patients with TM following COVID-19 (n = 12). Scale variables were compared between two independent groups using t-test or Wilcoxon-Mann-Whitney test depending on the distribution. In contrast to patients with TM, patients with tract-specific myelitis demonstrated higher levels of a proliferation-inducing ligand (APRIL), B cell activating factor (BAFF), interleukin (IL)-11, and thymic stromal lymphopoietin (TSLP). The BAFF/APRIL system is renowned for its involvement in the genesis and advancement of autoimmune disorders, and its pronounced increase in this case supports the autoimmune origin of the disease. The heightened activation of BAFF and APRIL cytokines, which promote B-cell maturation, suggests an autoimmune origin of tract-specific myelitis, thereby informing prognosis and treatment strategies for affected patients.

Central nervous system (CNS) infections can lead to long-term motor and cognitive complications in children.

We aimed to investigate the prevalence of attention deficit-hyperactivity disorder (ADHD) and assess the quality of life in children with CNS infections.

A longitudinal study was conducted on 94 children (aged 6 - 15 years) with CNS infection symptoms who were admitted to referral hospitals in Isfahan, Iran. Parents completed questionnaires assessing quality of life and neurological deficits at 6 and 12 months after discharge. All patients were evaluated by the corresponding physician for a final assessment.

Attention deficit-hyperactivity disorder symptoms were diagnosed in 30 patients, with viral encephalitis being the most common infection. The quality of life in children with CNS infections was significantly lower compared to that of healthy children.

Central nervous system infections negatively impact the quality of life in children. Screening for ADHD and managing affected children can help improve outcomes. Further research and interventions are needed to mitigate long-term complications.

Neurodegenerative disorders are characterized by the progressive deterioration of the central nervous system (CNS).  Depending on the affected regions, patients may experience a broad spectrum of neurological deficits, such as sensory, motor, cognitive, and psychological symptoms. Notably, cholesterol synthesis in CNS occurs in a de novo manner and is distinct from systemic lipid metabolism. However, lipids constitute a large portion of the brain and are involved in crucial brain functions like neurotransmission and synaptic plasticity. Emerging evidence suggests that alterations in lipid metabolism may contribute to the development and progression of different aspects of neurodegeneration, such as neuroinflammation, oxidative stress, and impaired neuronal membrane function.There are several critical changes in various lipid fractions, like cholesterol and triglycerides (TG), in individuals with neurodegenerative disorders. This narrative review aims to summarize the current understanding of the relationship between lipid profiles and neurodegenerative disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). The findings may have important implications for the development of novel diagnostic and therapeutic strategies targeting lipid-related pathways in the management of these debilitating neurological conditions.

Neurulation, as the formation of the basis of the nervous system, is the earliest and crucial stage of embryonic development, affecting the development of other parts of the embryonic body. During neurulation, the neural plate is formed through morphological changes. At the end of this stage, the neural tube is established and the central nervous system could be formed in the future. Although this embryonic process occurs morphologically, the precise study of nervous system evolution can be considered by different gene mutations in rodent embryos. Genetic assessments of embryos can finally cause the accurate discovery of the role of genes in embryo development, the stages of nervous system development, and possible associated diseases. Explanation of new findings in the field of neurulation with emphasis on genetics can be helpful in future embryonic studies, abnormalities, and treatments. Thus, the study of neural plate formation can play an important role in increasing the insight of embryological researchers in this field. In this review article, we aimed to collect basic embryonic data in rodent neurulation to provide important information for more laboratory investigations in this field.

Different degrees of T1-weighted (T1W) signal intensities in certain locations on brain magnetic resonance imaging (MRI) are characteristic features of neurological involvement in congenital portosystemic shunt (CPSS). Long-term accumulation of manganese (Mn) as a biomarker can lead to irreversible brain damage.

The aim of this study was to utilize quantitative brain MRI indicators to characterize brain signal differences in various regions in children with congenital portosystemic shunt. This may contribute to diagnosis, prognosis, and treatment decisions.

This was a case-control study. Thirty-two patients diagnosed with CPSS based on at least one of the following imaging studies—abdominal ultrasound, Digital Subtraction Angiography (DSA), and Computed Tomography (CT)—and who underwent brain MRI prior to interventional treatment or surgery were included as the Case Group in this study. The age of these patients varied from 22 months to 15 years. Brain MRI of thirty children aged 2 to 15 years, identified without liver or structural diseases, were selected as the Control Group.The brain imaging protocol included an axial spin-echo T1-weighted image (T1WI), an axial T2-weighted image (T2WI), an axial diffusion-weighted imaging (DWI), an axial T2-fluid attenuated inversion recovery (FLAIR) sequence, and a sagittal gradient-echo 3D T1W thin-slice sequence, which can be reconstructed into axial and coronal planes. We utilized quantitative MRI assessment based on the 3D T1-weighted sequence to evaluate intracranial signal differences. The quantitative index was categorized into two types: Globus pallidus-to-frontal subcortical white matter Index (GFI) and anterior pituitary-to-pons Index (API). GFI and API were measured and statistically analyzed on the 3D T1W sequence between the Case Group and the Control Group. GFI of the Case Group was also measured and analyzed between the 3D T1W sequence and the standard T1W sequence. Correlation analysis was applied between the GFI ratios and ammonia levels, as well as between the API ratios and ammonia levels in the Case Group. The duration of the study was more than three months.

Significant differences in GFI and API were observed in the Case Group compared with the Control Group (P < 0.01). There was also a statistical difference in GFI between the 3D T1W sequence and the standard T1W sequence (P < 0.01). However, the GFI and API ratios were not correlated with ammonia levels (P > 0.05). The Pearson correlation values were 0.147 and 0.190, respectively.

There was a correlation between different brain signals and congenital portosystemic shunt. Quantitative MRI assessment based on the 3D T1-weighted sequence could be used to evaluate these brain signal differences. A longitudinal study with multiple measurements would be beneficial for more accurately assessing such differences, enabling timely interventions, reducing complications, and avoiding lifelong drug therapy.

Tramadol, one of the most common opioid pain relievers, acts upon the µ-receptor in the central nervous system (CNS) to alleviate pain associated with various situations like postoperative pain, arthritis, and muscular pain. Additionally, it has been utilized to address depression and anxiety disorders. Extensive research has shown that tramadol can potentially inflict irreversible harm on different regions of the CNS, including the cerebrum, cerebellum, amygdala, and, notably, the hippocampal formation. However, the precise mechanism behind these effects remains unclear. Within this study, we conducted a comprehensive examination of the impacts of tramadol on the CNS, specifically focusing on hippocampal formation. 

In this study, we collected relevant articles published between 2000 and 2022 by conducting searches using specific keywords, including tramadol, tramadol hydrochloride, central nervous system, hippocampus, and hippocampal formation, in various databases.

The results of this study proposed several processes by which tramadol may impact the CNS, including the induction of apoptosis, autophagy, excessive production of free radicals, and dysfunction of cellular organelles. These processes ultimately lead to disturbances in neural cell function, particularly within the hippocampus. Furthermore, it is revealed that tramadol administration led to a significant decrease in the neural cell count and the volume of various regions within the brain and spinal cord.

Consequently, neuropsychological impairments, such as memory formation, attention deficits, and cognitive impairment, may happen. This finding highlights the potential impacts of tramadol on neural structures and warrants further investigation.

After water, tea is the most popular drink in the world, and its relationship with heart diseases, stroke, and cancer has been always considered by researchers. The aim of the present study is to assess the relationship between green tea or black tea consumption and stroke risk using systematic review and meta-analysis methods. To assess the required resources, PubMed, Scopus, Web of science, Cochrane electronic databases, and the Google Scholar search engine were searched. To assess the study heterogeneity, I2 indexes was used. Data were analyzed using STATA 14 software. P<0.05 was considered to be statistically significant. The preventive effect of green tea on cerebral stroke in the case-control studies was more than cohort studies and higher in women than men. Its effect was also lower in people who consume green tea more than 10 years in comparison to people who consume it less than 10 years. Green tea effect was higher in those who consume more than 5 cups/day than those with less than 5 cups/day. The effect of black tea consumption in men and in those who drank less than 5 cups a day or those who drink black tea for 10 years or more was estimated in preventive cohort studies. Green tea has a significant preventive effect on the risk of stroke in different doses and periods of consumption; however, black tea is preventive in a dose of fewer than 5 cups per day and for a period of more than 10 years.

In the wake of the COVID-19 pandemic, anosmia, the loss of the sense of smell, has emerged as a curious and widespread symptom. While the sense of smell in many individuals has eventually recovered, some grapple with anosmia for extended periods. In our recent study entitled "Magnetic Resonance Spectroscopy Findings of Brain Olfactory Areas in Patients With COVID-19-Related Anosmia," we embarked on a journey to explore the neurochemical underpinnings of anosmia in COVID-19 patients. This commentary extends our original research, providing insights into the evolving landscape of COVID-19-related anosmia and its implications.

Radiofrequency electromagnetic radiation (RFEMR) and extremely low-frequency electromagnetic fields (ELF-EMF) have emerged as noteworthy sources of environmental pollution in the contemporary era. The potential biological impacts of RF-EMR and ELF-EMF exposure on human organs, particularly the central nervous system (CNS), have garnered considerable attention in numerous research studies.

This article presents a comprehensive yet summarized review of the research on the explicit/implicit effects of RF-EMR and ELF-EMF exposure on CNS performance.

Exposure to RF-EMR can potentially exert adverse effects on the performance of CNS by inducing changes in the permeability of the blood-brain barrier (BBB), neurotransmitter levels, calcium channel regulation, myelin protein structure, the antioxidant defense system, and metabolic processes. However, it is noteworthy that certain reports have suggested that RF-EMR exposure may confer cognitive benefits for various conditions and disorders. ELF-EMF exposure has been associated with the enhancement of CNS performance, marked by improved memory retention, enhanced learning ability, and potential mitigation of neurodegenerative diseases. Nevertheless, it is essential to acknowledge that ELF-EMF exposure has also been linked to the induction of anxiety states, oxidative stress, and alterations in hormonal regulation. Moreover, ELF-EMR exposure alters hippocampal function, notch signaling pathways, the antioxidant defense system, and synaptic activities.

The RF-EMR and ELF-EMF exposures exhibit both beneficial and adverse effects. Nevertheless, the precise conditions and circumstances under which detrimental or beneficial effects manifest (either individually or simultaneously) remain uncertain.