Cortex Of Rats Research Articles

Changes in the Cyto- and Fibroarchitectonics of the Cerebellar Cortex in Rats Subjected to Extreme Physical Activity.

Physical overexertion surpassing the functional capacity of the nervous system causes the hyperactivation of the neural structures of the cerebellum. In turn, it causes the depletion of intracellular resources and progressive structural changes in cerebellar cells and fibers. These degenerative changes may lead to cerebellar dysfunction, including the worsening of coordination, balance, and motor functions. In order to maintain the health and functioning of the cerebellum and the nervous system in general, one needs to avoid physical overexertion and have enough time to recover. Three major types of Purkinje cells were identified in control group animals. After the forced swimming test, animals had significant morphological changes in pyriform cells, granule cells, internuncial neurons, and neuroglial cells. In particular, the extreme degeneration of granule cells was manifested via their fusion into conglomerates. These changes demonstrate that neurodegeneration in the cerebellum takes place in response to physical overexertion.

THE EFFECT OF SODIUM DEOXYCHOLATE AND TWЕЕN-20 ON THE ACTIVITY AND PROPERTIES OF NA+/K+-ATPase IN THE MIXED MEMBRANE FRACTION OF THE CEREBRAL CORTEX OF RATS

Interoduction. The present work extends the understanding of the activity of ouabain-sensitive (α2 and α3) and ouabain-resistant (α1) Na+/K+-ATPase isoforms in the mixed membrane fraction of rat cerebral cortex in the presence of various detergents. The aim of the study: to determine the activity of ouabain-sensitive (α2 and α3) and ouabain-resistant (α1) Na+/K+-ATPase isoforms by changing the concentration of Mg+2 ions in the incubation medium and using the detergents sodium deoxycholate and Tween-20. Material and methods. To determine Na+/K+-ATPase activity, we used the method of A. Kazennova et al. The reaction was triggered by adding ho-mogenate of cerebral cortex incubated with detergents; the samples were incubated for 30 minutes in a water bath at 370 C. The activity of ouabain-sensitive isoforms was determined by adding 200 μmol of ouabain to the incubation mixture. The activity of ouabain-sensitive isoforms was deter-mined by adding 200 μmol ouabain to the incubation mixture, and the activity of ouabain-resistant isoforms was determined as the difference between the total Na+/K+-ATPase activity and the activity of ouabain-sensitive isoforms. ATPase activity was determined by inorganic phosphate (Pi) increment as the difference between total ATPase activity, magnesium ATPase activity, in reaction with ammonium molybdate and tin chloride in the presence of ascorbic acid as a reducing agent. Results. At optimal concentrations of detergents Dox-Na (1.25 mg/mL) and Tween-20 (6.5 mg/mL), both ouabain-sensitive and ouabain-resistant Na+/K+-ATPase isoforms are characterized by normal activity dynamics from the concentration of Mg2+ ions. Consequently, the use of detergents at given concentrations does not change the ability of enzymes to conformational rearrangements during the reaction cycle. It was found that both used detergents allow to reveal a significant percentage of latent activity of ouabain-sensitive (α2 and α3) and ouabain-resistant (α1) Na+/K+-ATPase isoforms in the mixed mebran fraction of the cerebral cortex of rats. Conclusion. The study of Mg2+-dependent properties revealed a similar character of the curves of dependence of enzyme activity on the concentra-tion of Mg2+ in the incubation medium for all Na+/K+-ATPase isoforms studied

Transcriptomic analysis of rat prefrontal cortex following chronic stress induced by social isolation – Relevance to psychiatric and neurodevelopmental illness, and implications for treatment

Social isolation is an established risk factor for psychiatric illness, and became increasingly topical with the spread of SARS-CoV-2. We used RNA sequencing (RNA-Seq) to enable unbiased assessment of transcriptomic changes within the prefrontal cortex (PFC) of isolation-reared rats. To provide insight into the relevance of this manipulation for studying human illness, we compared differentially expressed genes (DEGs) and enriched biological functions against datasets involving post-mortem frontal cortical tissue from patients with psychiatric and neurodevelopmental illnesses. Sixteen male Sprague-Dawley rats were reared in groups of four or individually from weaning on postnatal day (PND) 22–24 until PFC tissue collection for RNA-Seq (PND64-66). We identified a total of 183 DEGs in isolates, of which 128 mirrored those in PFC tissue from patients with stress-related mental illnesses and/or neurodevelopmental conditions featuring social deficits. Seventy-one encode proteins classed as druggable by the gene-drug interaction database. Interestingly there are antagonists or inhibitors for the products of three of these up-regulated DEGs (Hrh3, Snca and Sod1) and agonists or activators for products of six of these down-regulated DEGs (Chrm4, Klf2, Lrrk2, Nr4a1, Nr4a3 and Prkca). Some have already undergone pre-clinical and clinical evaluation, and studies with the remainder may be warranted. Changes to Hrh3, Sod1, Chrm4, Lrrk2, Nr4a1 and Prkca were replicated in an independent cohort of sixteen male Sprague-Dawley rats via quantitative reverse transcription polymerase chain reaction (qRT-PCR). Our findings support the continued use of post-weaning isolation rearing to investigate the neurobiology of stress-related disorders and evaluate therapeutic targets.

Methodological approaches to the creation of a biological model of smoke in landscape fires

Introduction. Long-term smoke from landscape fires causes various health problems, primarily affecting the respiratory, cardiovascular, and nervous systems. To substantiate safe levels of exposure to smoke from landscape fires, it is necessary to create an adequate biological model for smoke that is close to natural conditions. The aim of the study is to develop and test methodological approaches to creating a biological model for smoke during landscape fires to substantiate safe levels of exposure. Materials and methods. Using the developed biological model, we studied the effects of smoke from landscape fires on white rats. We assessed the functional state of the central nervous system based on rat behaviour and EEG examination results, conducted a morphological study of the cerebral cortex and testes of white rats, and examined the offspring immediately after birth and at puberty. Results. We studied the biological response of white rats exposed to inhalation smoke from landscape fires for different durations. The main criterion indicators of health disorders in the central nervous and reproductive systems of animals were identified. Limitations. The study is limited by the lack of data on safe levels of exposure to smoke from landscape fires on the central nervous system and reproductive toxicity. Conclusion. Testing of the developed method allowed identifying the exposure load of carbon monoxide and ultrafine particles PM2.5, at which changes in the nervous and reproductive systems are minimal. A method for calculating safe levels of exposure for the central nervous and reproductive systems, as well as for the effect on offspring, is proposed. An algorithm for conducting research in studying the effect of smoke from landscape fires on the body has been developed.

Glutamate concentration of medial prefrontal cortex is inversely associated with addictive behaviors: a translational study

In both preclinical and clinical settings, dysregulated frontostriatal circuits have been identified as the underlying neural substrates of compulsive seeking/taking behaviors manifested in substance use disorders and behavioral addictions including internet gaming disorder (IGD). However, the neurochemical substrates for these disorders remain elusive. The lack of comprehensive cognitive assessments in animal models has hampered our understanding of neural plasticity in addiction from these models. In this study, combining data from a rat model of compulsive taking/seeking and human participants with various levels of IGD severity, we investigated the relationship between regional glutamate (Glu) concentration and addictive behaviors. We found that Glu levels were significantly lower in the prelimbic cortex (PrL) of rats after 20-days of methamphetamine self-administration (SA), compared to controls. Glu concentration after a punishment phase negatively correlated with acute drug-seeking behavior. In addition, changes in Glu levels from a drug naïve state to compulsive drug taking patterns negatively correlated with drug-seeking during both acute and prolonged abstinence. The human data revealed a significant negative correlation between Glu concentration in the dorsal anterior cingulate cortex (dACC), the human PrL counterpart, and symptoms of IGD. Interestingly, there was a positive correlation between Glu levels in the dACC and self-control, as well as mindful awareness. Further analysis revealed that the dACC Glu concentration mediated the relationship between self-control/mindful awareness and IGD symptoms. These results provide convergent evidence for a protective role of dACC/PrL in addiction, suggesting interventions to enhance dACC glutamatergic functions as a potential strategy for addiction prevention and treatment.

Acute Hypobaric Hypoxia Causes Alterations in Acetylcholine-Mediated Signaling Through Varying Expression of Muscarinic Receptors in the Prefrontal Cortex and Cerebellum of Rats' Brain.

Sharma, Narendra Kumar, Mansi Srivastava, Tikam Chand Dakal, Vipin Ranga, and Pawan Kumar Maurya. Acute hypobaric hypoxia (HH) causes alterations in acetylcholine-mediated signaling through varying expression of muscarinic receptors in the PFC and cerebellum of rats' brain. High Alt Med Biol. 00:00-00, 2024. Background: Muscarinic receptor (CHRM) proteins are G-protein-associated acetylcholine receptors found in neuronal membranes. Five major subtypes, CHRM1-CHRM5, modulate acetylcholine in central nervous system signaling cascades. CHRM1, CHRM3, and CHRM5 are linked to Gαq/Gα11 proteins, whereas CHRM2 and CHRM4 are linked to Gαi/Gαo proteins. Objective: Limited research has been conducted to explore the impact of HH on CHRM gene expressions. It is caused by low oxygen availability at high altitudes, which impairs neurotransmission, cognitive performance, and physiological functions. Previous studies have shown that exposure to hypoxia leads to a reduction in CHRM receptors, which in turn causes alteration in signal transduction, physiological responses, cognitive deficits, and mood alterations. Method: In the present study, we have used semiquantitative PCR to measure muscarinic receptor gene expression after 6, 12, and 24 hours of HH exposure at 25,000 feet using a decompression chamber in rat brain's PFC and cerebellum. Result: We have found that CHRM1-CHRM5 downregulated after acute exposure to hypoxia until 12 hours, and then, the expression level of these receptors increased to 24 hours when compared with 12 hours in PFC. All subtypes have shown a similar pattern in PFC regions under hypoxia exposure. On the other hand, these receptors have shown altered expression at different time points in the cerebellum. CHRM1 and CHRM4 acutely downregulated, CHRM2 and CHRM5 downregulated, while CHRM3 upregulated after hypoxia exposure. Conclusion: Our study, for the first time, has shown the altered expressions of muscarinic receptors under temporal hypoxia exposure. The altered expression pattern has shown an association with acclimatization and protection against necrosis due to hypoxia. This study may pave further investigations for understanding and addressing the cognitive, behavioral, and physiological impacts of hypoxia and therapeutic development.

Effects of Vitamin C on Aluminum Chloride- Induced Neurotoxicity on the Hippocampal Cortex of Adult Wistar Male Rats

This study aimed to evaluate the neuroprotective effects of Vitamin C on aluminum chloride (AlCl₃)- induced brain damage, focusing on behavioral, biochemical, and histomorphological outcomes in a rodent model. Study Design: A total of 42 healthy male rats were randomly assigned to three groups: control, AlCl₃ -only, and AlCl₃ plus Vitamin C (500 mg/kg and 1000 mg/kg). The AlCl₃ groups received daily doses of AlCl₃, while the Vitamin C groups received concurrent Vitamin C supplementation. Methodology: Body weight, behavioral changes, biochemical markers of oxidative stress (MDA, SOD, GSH), and inflammation (TNF-α, IL-6) were assessed. Histomorphological analysis of the hippocampus was performed to evaluate structural damage. Behavioral assessments included locomotor and exploratory activity tests. Biochemical analyses measured oxidative stress and antioxidant enzyme activities. Results: AlCl₃ administration resulted in significant body weight loss, increased oxidative stress (elevated MDA, and SOD levels), and heightened inflammation (elevated TNF-α and IL-6). Behavioral tests showed increased excitatory activities, and increased anxiety levels as seen in increased rearing and grooming activities. Histomorphological examination revealed significant hippocampal damages as seen in the pale staining, shrunken pyramidal cells. Vitamin C co- administration mitigated these adverse effects, demonstrating reduced body weight loss, lower oxidative stress, decreased inflammation, and improved behavioral performance. Histological analysis indicated less hippocampal damage in the Vitamin C treated groups. Conclusion: As an antioxidant, Vitamin C effectively attenuates the neurotoxic effects of AlCl₃ by reducing oxidative stress and inflammation, and by protecting the hippocampal cellular integrity. These findings suggest that Vitamin C holds potential as a therapeutic agent for mitigating neurotoxicity induced by aluminum compounds.

Protective effect of aspirin and gentisic acid, a plant-derived phenolic acid, on acrylamide-induced neurotoxicity by inhibiting apoptosis and autophagy.

Acrylamide (ACR) is a toxic agent for humans and animals. Gentisic acid, anaspirinmetabolite, has antioxidant activity. Therefore, the present study investigated the probable protective effects of aspirin and gentisic acid on ACR-induced neurotoxicity in PC12 cells and rats. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to assess the effects of aspirin and gentisic acid (1.25, 2.5, 5 µM) on ACR (5 mM) toxicity. Male Wistar rats were randomly divided into 13 groups: (1) Control group, (2) ACR (50 mg/kg, 11 days, i.p.), (3-5) ACR + aspirin (25, 50, 75 mg/kg, 11 days, p.o.), (6-8) ACR + gentisic acid (25, 50, 75 mg/kg, 11 days, p.o.), (9) ACR + vitamin E (200 mg/kg, every other day, i.p.), (10, 11) Aspirin (75, 100 mg/kg, 11 days, p.o.), (12, 13) Gentisic acid (75, 100 mg/kg, 11 days, p.o.). Behavioral tests were assessed on the final day of the study. In the cerebral cortex, malondialdehyde (MDA), glutathione (GSH), cleaved-caspase-3, and microtubule-associated protein 1A/1B-light chain 3 (LC3) protein levels were evaluated. When compared with the ACR group, aspirin (2.5, 5 µM) and gentisic acid (2.5 µM) significantly enhanced cell viability. In comparison to the control group, ACR induced severe motor impairment, elevated MDA, cleaved-caspase-3, LC3 II/I ratio, and decreased GSH levels in the cerebral cortex of rats. ACR-induced changes were significantly reversed by aspirin and gentisic acid (25 mg/kg). Oxidative stress, apoptosis, and autophagy play important roles in the neurotoxicity of ACR. Aspirin and gentisic acid significantly reduced ACR-induced toxicity by inhibiting the mentioned mechanisms.

Inulin may prevent the high-fat diet induced-obesity via suppressing endocannabinoid system in the prefrontal cortex in Wistar rats

High-fat diets contribute to various metabolic disorders. Inulin supplementation has been shown to reduce appetite, lower food intake, and promote weight loss. Although there is evidence that the endocannabinoid system has metabolic effects in the prefrontal cortex, studies investigating the effects of inulin on the endocannabinoid system are limited. This study investigated the impact of inulin on obesity through the endocannabinoid system in the prefrontal cortex. Twenty-four male Wistar rats were fed one of four diets over 12 weeks. Findings indicated that a high-fat diet led to obesity, whereas inulin reduced food intake and supported weight loss. Consequently, inulin supplementation both prevented obesity and significantly decreased the expressions of Adrb3 and Adcy1, and anandamide and 2-arachidonylglycerol levels in the prefrontal cortex. Additionally, inulin lowered leptin in circulation and stimulated Trpv1. Thus, inulin may mitigate obesity development, possibly by modulating gene expressions linked to obesity in the prefrontal cortex via endocannabinoids.

Effects of electroacupuncture at Fengchi (GB20) on motor function and GFAP/NeuN expression around the ischemic tissue of the motor cortex in MCAO rats

Effects of electroacupuncture at Fengchi (GB20) on motor function and GFAP/NeuN expression around the ischemic tissue of the motor cortex in MCAO rats

Neural decoding and feature selection methods for closed-loop control of avoidance behavior

Objective.Many psychiatric disorders involve excessive avoidant or defensive behavior, such as avoidance in anxiety and trauma disorders or defensive rituals in obsessive-compulsive disorders. Developing algorithms to predict these behaviors from local field potentials (LFPs) could serve as the foundational technology for closed-loop control of such disorders. A significant challenge is identifying the LFP features that encode these defensive behaviors.Approach.We analyzed LFP signals from the infralimbic cortex and basolateral amygdala of rats undergoing tone-shock conditioning and extinction, standard for investigating defensive behaviors. We utilized a comprehensive set of neuro-markers across spectral, temporal, and connectivity domains, employing SHapley Additive exPlanations for feature importance evaluation within Light Gradient-Boosting Machine models. Our goal was to decode three commonly studied avoidance/defensive behaviors: freezing, bar-press suppression, and motion (accelerometry), examining the impact of different features on decoding performance.Main results.Band power and band power ratio between channels emerged as optimal features across sessions. High-gamma (80-150 Hz) power, power ratios, and inter-regional correlations were more informative than other bands that are more classically linked to defensive behaviors. Focusing on highly informative features enhanced performance. Across 4 recording sessions with 16 subjects, we achieved an average coefficient of determination of 0.5357 and 0.3476, and Pearson correlation coefficients of 0.7579 and 0.6092 for accelerometry jerk and bar press rate, respectively. Utilizing only the most informative features revealed differential encoding between accelerometry and bar press rate, with the former primarily through local spectral power and the latter via inter-regional connectivity. Our methodology demonstrated remarkably low training/inference time and memory usage, requiring<310 ms for training,<0.051 ms for inference, and 16.6 kB of memory, using a single core of AMD Ryzen Threadripper PRO 5995WX CPU.Significance.Our results demonstrate the feasibility of accurately decoding defensive behaviors with minimal latency, using LFP features from neural circuits strongly linked to these behaviors. This methodology holds promise for real-time decoding to identify physiological targets in closed-loop psychiatric neuromodulation.

Differential gene expression and chromatin accessibility in the medial prefrontal cortex associated with individual differences in rat behavioral models of opioid use disorder.

Opioid use disorder (OUD) is a neuropsychological disease that has a devastating impact on public health. Substantial individual differences in vulnerability exist, the neurobiological substrates of which remain unclear. To address this question, we investigated genome-wide gene transcription (RNA-seq) and chromatin accessibility (ATAC-seq) in the medial prefrontal cortex (mPFC) of male and female rats exhibiting differential vulnerability in behavioral paradigms modeling different phases of OUD: Withdrawal-Induced Anhedonia (WIA), Demand, and Reinstatement. Ingenuity Pathway Analysis (IPA) of RNA-seq revealed greater changes in canonical pathways in Resilient (vs. Saline) rats in comparison to Vulnerable (vs. Saline) rats across 3 paradigms, suggesting brain adaptations that might contribute to resilience to OUD across its trajectory. Analyses of gene networks and upstream regulators implicated processes involved in oligodendrocyte maturation and myelination in WIA, neuroinflammation in Demand, and metabolism in Reinstatement. Motif analysis of ATAC-seq showed changes in chromatin accessibility to a small set of transcription factor (TF) binding sites as a function either of opioid exposure (i.e., morphine versus saline) generally or of individual vulnerability specifically. Some of these were shared across the 3 paradigms and others were unique to each. In conclusion, we have identified changes in biological pathways, TFs, and their binding motifs that vary with paradigm and OUD vulnerability. These findings point to the involvement of distinct transcriptional and epigenetic mechanisms in response to opioid exposure, vulnerability to OUD, and different stages of the disorder.

The Possible Protective Effect of Taurine on Bisphenol Induced Structural Changes on the Cerebral Cortex of Rats: Histological and Immunohistochemical Study.

Bisphenol A (BPA) is a chemical compound that has been used in many industries, such as paints and dental sealants. Taurine is a semi-essential amino acid with antioxidant, anti-inflammatory, and anti-apoptotic actions. This study aimed to evaluate the possible protective effect of taurine on BPA-induced structural changes in the cerebral cortex of rats using histological and immunohistochemical methods. 35 Wistar rats (180-200 gm) were divided into control: 10 rats; Group I: 5 rats received corn oil (0.5 mL/day); Group II (Bisphenol low dose; BPAL): 5 rats received a low dose of BPA (25 mg/kg/three times/week); Group III (Bisphenol high dose; BPAH): 5 rats received a high dose of BPA (100 mg/kg/three times/week; Group IV: (BPAL + taurine): 5 rats received taurine 100 mg/kg/day and BPAL (25 mg/kg/three times/week); Group V: (BPAH + taurine): 5 rats received taurine 100 mg/kg/day and BPH (100 mg/kg/ three times/week). BPAL& BPAH groups showed significant dose-dependent histological changes of the neuropil, pyramidal, and neuroglial cells at H&E stained sections, significantly increased GFAP, caspase- 3 immunohistochemical reaction with cells positive for Ki67 with many mitotic figures. BPAL + taurine and BPAH + taurine groups showed amelioration of the previously mentioned results. Taurine ameliorated the structural changes induced by BPA in the cerebral cortex of rats.

In-silico analysis of ethanol peel extract of Citrus sinensis on mercury chloride-induced prefrontal cortex damage in Wistar rat

This study evaluated the effect of ethanolic extract of Citrus sinensis peel on mercury chloride-induced changes in the prefrontal cortex of adult Wistar rats. Twenty-five Wistar rats were purchased and divided into five groups containing five animals in each group. Group 1 was administered with distilled water, Group 2, Group 3, Group 4, and Group 5 were administered with 5 mg/kg of mercury chloride only, 5 mg/kg of mercury chloride and 140 mg/kg Silymarin, 5 mg/kg mercury chloride and 1000 mg/kg of ethanoic extract of orange peel, and 5 mg/kg mercury chloride and 1500 mg/kg of ethanoic extract of orange peel. All administration was done orally and the administration lasted for 14 days. The animals were sacrificed humanely using 75 mg/kg ketamine intraperitoneally and prefrontal was dissected out. Part was homogenized in 0.1M phosphate buffered saline for the estimation of superoxide dismutase (SOD), and catalase (CAT) activities, and Malondialdehyde (MDA) level and the other part was fixed by immersion in 10 neutral buffered formal-saline for histological evaluation. The chemical structure of sixteen compounds from Citrus sinensis peel obtained from GC-MS analysis reported in the literature were retrieved from the PubChem compound database and the crystal structure of human peroxisome proliferator- activated receptor gamma (PPARγ; PDB:ID: 2P4Y) reported to increase the expression of catalase gene, human extracellular copper-zinc superoxide dismutase enzyme (PDB ID: 2JLP) and mammalian 15-lipoxygenase - 1 enzyme (PDB ID: 2P0M) responsible for the production of lipid peroxidation were retrieved from the PDB database. Ligands and protein preparation, docking and MM-GBSA relative binding free energy calculation were done in Maestro 2023.1. Data obtained was analyzed using the IBM SPSS (version 25) using one-way ANOVA and p-value &lt; 0.05 was considered statistically significant. The results indicate that the MDA level in control Group(13.29±1.183 μmol) is statistically significantly lower compared to the Group 2 (21.88±1.96 μmol), group 3 (27.44±3.52 μmol), Group 4 (22.20±1.16 μmol) and Group 5 (25.40±3.13 μmol). No statistically significant difference was observed in SOD activity. The CAT activities in control group (53.51±6.83 nmol/ml) was statistically significantly lower compared to the group 2 (26.21±3.70 nmol/ml), Group 3 (27.17±5.32 nmol/ml), Group 4 (25.30±4.24 nmol/ml) and Group5 (26.59±4.22 nmol/ml).The present study suggests, ethanolic extract of Citrus sinensis peel have protective effects on mercury-induced changes in prelimbic part of the prefrontal cortex of adult Wistar rats.

Biochemical and histological analysis of ethanol peel extract of Citrus sinensis on mercury chloride-induced prefrontal cortex damage in Wistar rats

Mercury is one of the heavy metals which is found extensively in many environmental and certain occupational settings. It is the third most dangerous heavy metal and its toxicity causes serious risks to health through unfavorable pathological and biochemical effects. Sweet orange is the fruit of the citrus species (Citrus sinensis) in the family Rutaceae.. Over time there has been increasing interest in the utilization of these peels for both nutritional and medicinal purposes. Studies have reported the antioxidant potential of orange peel oil in laboratory rodents, indicating its protective effect against oxidative stress-mediated ailments. The study evaluated the effect of ethanolic extract of Citrus sinensis peel on mercury chloride-induced changes in the prefrontal cortex of adult Wistar rats. Twenty-five Wistar rats were purchased and divided into five groups containing five animals in each group. Group 1 was administered with distilled water, Group 2, Group 3, Group 4, and Group 5 were administered with 5 mg/kg of mercury chloride only, 5 mg/kg of mercury chloride and 140 mg/kg Silymarin, 5 mg/kg mercury chloride and 1000 mg/kg of ethanoic extract of orange peel, and 5 mg/kg mercury chloride and 1500 mg/kg of ethanoic extract of orange peel. All administration was done orally and the administration lasted for 14 days. The animals were sacrificed humanely using 75 mg/kg ketamine intraperitoneally and prefrontal was dissected out. Part was homogenized in 0.1M phosphate buffered saline for the estimation of superoxide dismutase (SOD), and catalase (CAT) activities, and Malondialdehyde (MDA) level and the other part was fixed by immersion in 10 neutral buffered formal-saline for histological evaluation. The results indicate that the MDA level in control Group(13.29±1.183 μmol) is statistically significantly lower compared to the Group 2 (21.88±1.96 μmol), group 3 (27.44±3.52 μmol), Group 4 (22.20±1.16 μmol) and Group 5 (25.40±3.13 μmol). No statistically significant different that was observed in SOD activity. It CAT activities in control group (53.51±6.83 nmol/ml) is statistically significantly lower compared to the group 2 (26.21±3.70 nmol/ml), Group 3 (27.17±5.32 nmol/ml), Group 4 (25.30±4.24 nmol/ml) and Group5 (26.59±4.22 nmol/ml). Protective role of the extract was observed from the histological evaluation. This study suggests that ethanolic extract of Citrus sinensis peel have protective effects on mercury-induced changes in prelimbic part of the prefrontal cortex of adult Wistar rats.

Protective Effect of Flax Seed Oil on acetaminophen- induced toxicity in the renal cortex of albino rats

Protective Effect of Flax Seed Oil on acetaminophen- induced toxicity in the renal cortex of albino rats

Mechanically adaptive and deployable intracortical probes enable long-term neural electrophysiological recordings

Flexible intracortical probes offer important opportunities for stable neural interfaces by reducing chronic immune responses, but their advances usually come with challenges of difficult implantation and limited recording span. Here, we reported a mechanically adaptive and deployable intracortical probe, which features a foldable fishbone-like structural design with branching electrodes on a temperature-responsive shape memory polymer (SMP) substrate. Leveraging the temperature-triggered soft-rigid phase transition and shape memory characteristic of SMP, this probe design enables direct insertion into brain tissue with minimal footprint in a folded configuration while automatically softening to reduce mechanical mismatches with brain tissue and deploying electrodes to a broader recording span under physiological conditions. Experimental and numerical studies on the material softening and structural folding-deploying behaviors provide insights into the design, fabrication, and operation of the intracortical probes. The chronically implanted neural probe in the rat cortex demonstrates that the proposed neural probe can reliably detect and track individual units for months with stable impedance and signal amplitude during long-term implantation. The work provides a tool for stable neural activity recording and creates engineering opportunities in basic neuroscience and clinical applications.

Pairing tones with vagus nerve stimulation improves brain stem responses to speech in the valproic acid model of autism.

Receptive language deficits and aberrant auditory processing are often observed in individuals with autism spectrum disorders (ASD). Symptoms associated with ASD are observed in rodents prenatally exposed to valproic acid (VPA), including deficits in speech sound discrimination ability. These perceptual difficulties are accompanied by changes in neural activity patterns. In both cortical and subcortical levels of the auditory pathway, VPA-exposed rats have impaired responses to speech sounds. Developing a method to improve these neural deficits throughout the auditory pathway is necessary. The purpose of this study was to investigate the ability of vagus nerve stimulation (VNS) paired with sounds to restore degraded inferior colliculus (IC) responses in VPA-exposed rats. VNS paired with the speech sound "dad" was presented to a group of VPA-exposed rats 300 times per day for 20 days. Another group of VPA-exposed rats were presented with VNS paired with multiple tone frequencies for 20 days. The IC responses were recorded from 19 saline-exposed control rats and 18 VPA-exposed with no VNS, 8 VNS-speech paired VPA-exposed, and 7 VNS-tone paired VPA-exposed female and male rats. Pairing VNS with tones increased the IC response strength to speech sounds by 44% compared to VPA-exposed rats alone. Contrarily, VNS-speech pairing significantly decreased the IC response to speech compared with VPA-exposed rats by 5%. The present research indicates that pairing VNS with tones improved sound processing in rats exposed to VPA and suggests that auditory processing can be improved through targeted plasticity.NEW & NOTEWORTHY Pairing vagus nerve stimulation (VNS) with sounds has improved auditory processing in the auditory cortex of normal-hearing rats and autism models of rats. This study tests the ability of VNS-sound pairing to restore auditory processing in the inferior colliculus (IC) of valproic acid (VPA)-exposed rats. Pairing VNS with tones significantly reversed the degraded sound processing in the IC in VPA-exposed rats. The findings provide evidence that auditory processing in autism rat models can be improved through VNS.

ChangPu YuJin Tang improves Tourette disorder symptoms by modulating amino acid neurotransmitters in IDPN model rats.

Changpu Yujin Tang(CPYJT), a Chinese herbal compound, is an effective therapeutic strategy for pediatric patients with Tourette disorder (TD). Therefore, this work aims to investigate the therapeutic mechanisms of CPYJT. Behavioral and cellular ultrastructural evaluation of the therapeutic effects of CPYJT in TD model rats. Colorimetric methods, reverse transcription‑quantitative PCR, and Western Blot were used to measure the altered levels of GLU, GABA, and the levels of VGLUT1, GLUD1, GABRA3, and GAD65 in the cortex, striatum, and thalamus of the TD model rats after 7, 14, 21, and 28 days of CPYJT administration. CPYJT significantly reduced stereotypic behavior and motor behavior scores in TD model rats. CPYJT ameliorates myelin structural damage in TD model rat neuronal cells. CPYJT decreased GLU content, elevated GABA content, decreased GLUD1 and VGLUT1 levels, and elevated GAD65 and GABRA3 levels in TD model rats' cortex, striatum, and thalamus. CPYJT has different regulatory time points in the cortex, striatum, and thalamus for critical factors of amino acid-based neurotransmission. CPYJT protects behavioral and structural damage of neuronal cells in multiple brain regions in TD model rats.

Remodeling of the structural components of the capsule and glomerular zone of the adrenal glands cortex of white rats under the influence of a complex of food additives at the late terms of the experimental study

With food additives, we can add flavour to food, extend its shelf life, and make it look good. However, even small amounts of these additives can lead to diseases of various organs and systems. The aim of our work is to establish metrics and morphological changes in the structure of the capsule and the glomerular zone of the cortex of the adrenal glands of rats at the later stages of the experimental study under the conditions of consumption of a complex of food additives: monosodium glutamate, sodium nitrite and Ponceau 4R. The control group of rats consumed oral drinking water and saline. The rats of the experimental groups were orally administered once a day with a 10 % solution of sodium nitrite (E250), sodium glutamate (E621) or Ponceau 4R. The dosages of food additives were two times lower than the permissible norm in food. The rats were withdrawn from the experiment after 8, 12 and 16 weeks. The adrenal glands were removed for the study. Paraffin sections were stained with hematoxylin and eosin, and semi-thin sections with toluidine blue, and examined using a light microscope Biorex with a digital microphoto attachment DSM 900. Ultrathin sections were examined in a TEM-125 K electron microscope. For morphometric analysis, the structure of the capsule and the glomerular zone of the cortex of the adrenal glands of rats at the later stages of the experimental study was studied. The study results were analysed using the software package “InStat”. At the late stages of the experimental study, the adrenal capsule underwent irreversible changes. The average thickness of the adrenal connective tissue capsule decreased by the end of the 16th week of the experimental research. Similarly, the average thickness of the cortex decreased with each subsequent week relative to the control values, indicating significant structural and functional disorders. The average thickness of the glomerular zone of the adrenal cortex periodically changed as a compensatory reaction in response to the administration of a complex of food additives to rats. The phenomena of nucleus pyknosis and sludge syndrome were detected, which indicated compensatory and adaptive processes at the microscopic level. The analysis of electron micrographs revealed destroyed granular endoplasmic reticulum cisternae and mitochondrial remnants. Thus, it has been established that using a complex of food additives (monosodium glutamate, sodium nitrite and Ponceau 4R) directly affects the adrenal glands of rats. This effect causes structural changes in the cortex and medulla, causing alteration and hypertrophy of cells in these areas. Additionally, hyperhydration of the connective tissue stroma and compensatory-restorative reactions aimed at transcription factors and internal mechanisms of nitric oxide formation were recorded.