Neuronal Vacuolation Research Articles

Histopathological substrate of increased T2 signal in the anterior temporal lobe white matter in temporal lobe epilepsy associated with hippocampal sclerosis.

This study was undertaken to analyze the histology underlying increased T2 signal intensity (iT2SI) in anterior temporal lobe white matter (aTLWM) epilepsy due to hippocampal sclerosis (TLE/HS). Twenty-three patients were included: 16 with increased T2 signal in the aTLWM and seven with HS only. Magnetic resonance imaging (MRI) findings were consistent across two neuroradiologists (kappa = .89, p < .001). Quantification of neuronal cells, astrocytes, oligodendrocytes, and vacuolization in the white matter of temporal lobe specimens was performed by immunohistochemistry (neuronal nuclear antigen, glial fibrillary acidic protein, oligodendrocyte transcription factor, and basic myelin protein, respectively). Surgical specimens from TLE/HS patients with and without iT2SI in the aTLWM were compared. Samples of aTLWM were divided into three groups, according to MRI features: G1 = samples of iT2SI, G2 = samples with normal T2 signal intensity from patients without white matter imaging abnormalities, and G3 = samples with normal T2 signal intensity adjacent to areas with iT2SI. Patients with increased T2 signal had a significantly younger age at epilepsy onset (p < .035). Histological analysis revealed a higher percentage of vacuolar area in these patients (p < .004) along with a lower number of ectopic neurons (p = .042). No significant differences were found in astrocyte or oligodendrocyte counts among groups. A higher proportion of vacuoles in regions with iT2SI may be the histopathologic substrate of this signal alteration in the white matter of the temporal lobe in patients with TLE/HS. This method of quantifying vacuoles using digital image analysis proved reliable and cost-effective.

Unraveling autophagic imbalances and therapeutic insights in Mecp2-deficient models.

Loss-of-function mutations in MECP2 are associated to Rett syndrome (RTT), a severe neurodevelopmental disease. Mainly working as a transcriptional regulator, MeCP2 absence leads to gene expression perturbations resulting in deficits of synaptic function and neuronal activity. In addition, RTT patients and mouse models suffer from a complex metabolic syndrome, suggesting that related cellular pathways might contribute to neuropathogenesis. Along this line, autophagy is critical in sustaining developing neuron homeostasis by breaking down dysfunctional proteins, lipids, and organelles.Here, we investigated the autophagic pathway in RTT and found reduced content of autophagic vacuoles in Mecp2 knock-out neurons. This correlates with defective lipidation of LC3B, probably caused by a deficiency of the autophagic membrane lipid phosphatidylethanolamine. The administration of the autophagy inducer trehalose recovers LC3B lipidation, autophagosomes content in knock-out neurons, and ameliorates their morphology, neuronal activity and synaptic ultrastructure. Moreover, we provide evidence for attenuation of motor and exploratory impairment in Mecp2 knock-out mice upon trehalose administration. Overall, our findings open new perspectives for neurodevelopmental disorders therapies based on the concept of autophagy modulation.

Porcine Astrovirus Infection in Brains of Pigs in Korea.

Recently, neurological diseases associated with astroviruses (AstVs) have been reported in pigs, ruminants, minks, and humans. In 2017, neuro-invasive porcine astrovirus (Ni-PAstV) 3 was detected in the central nervous system (CNS) of pigs with encephalomyelitis in Hungary and the USA. In the process of diagnosing domestic pigs exhibiting neurological signs, histopathologic lesions of non-suppurative encephalomyelitis with meningitis, neuronal vacuolation, and gliosis were detected, and PAstV was identified using reverse transcriptase PCR in CNS samples of four pigs in three farms from August to September in 2020, South Korea. Subsequently, the ORF2 region was successfully acquired from three brain samples, facilitating subsequent analysis. Four genotypes of PAstV (PAstV1, 3, 4, and 5) were detected, and coinfection of PAstV with multiple genotypes was observed in brain samples. This is the first study to report Ni-PAstV infection in pigs in South Korea.

Lead toxicity in African catfish: Promising role of magnetite nanogel against etho-neurological alterations, antioxidant suppression, gene toxicity, and histopathological/ immunohistochemical disruptions

Recently, toxicity with heavy metals has been a major health issue because of its detrimental impact on fish and fish consumers. Different from previous studies, here we are the first trial to assess the impending effect of the watery solution of magnetite (Fe3O4) nano gel (MG) against toxicity of lead (Pb) in African catfish (Clarias gariepinus). The evaluation included recording ethology, brain function, antioxidant traits, gene expression plus histopathological/and immunohistochemical assessment and residues in the brain tissues. Fish (n = 160; Bwt: 100.00 ± 7.39 g) were randomly allotted into four groups (40/group; 10 fish per replicate; four replicates/group). The first group (control) was not exposed to MG or lead chloride (PbCl2 as a source of Pb). The second (MG) group was exposed to 1.2 mg/L of MG. The third group (Pb) was subjected to PbCl2 (69.30 mg/L) toxicity. Meanwhile, the fourth group (MG + Pb) was subjected to PbCl2 toxicity (69.30 mg/L) and at the same time, treated with 1.2 mg/L of MG. The trial lasted for 45 days. The exposure to Pb resulted in notable ethological alterations (unusual swimming, surfacing, loss of equilibrium, laterality, and spiral movement). A clear decline in serum antioxidant parameters (catalase, reduced glutathione content, and total antioxidant capacity) and brain neurotransmitter (acetylcholine esterase) was observed in the Pb-exposed fish. An up-regulation of the myeloid differentiation factor 88 (MyD88), heat shock protein 70 (HSP70), and toll-like receptor (TLR-1 and TLR-5) genes of the brain plus higher residual Pb deposition in brain tissues were induced by Pb exposure. Additionally, prominent histopathological lesions including neuronal degeneration and vacuolation as well as a strong caspase-3 and a weak B-cell lymphoma 2 (bcl-2) immune expression were obvious in the brain. Remarkably, the addition of MG in water induced an improvement in these biomarkers and retrieved the histopathological changes. Considering these outcomes, MG is a promising candidate and an innovative approach as antitoxic against the toxicity of Pb for sustaining the performance and health of African catfish.

Protective effect of cholecalciferol against cobalt-induced neurotoxicity in rats: ZO-1/iFABP, ChAT/AchE and antioxidant pathways as potential therapeutic targets.

Cobalt (Co) toxicity has been reported to produce central nervous system and gastrointestinal abnormalities. This study assessed the therapeutic effect of cholecalciferol (Cho) supplementation against damages caused by sub-acute (14-day) cobalt chloride (CoCl2) exposure in the brain and intestines. Thirty-five male Wistar rats were divided equally into five groups: Group I (control) received no treatment; Group II received oral CoCl2 (100 mg/kg) only; Groups III, IV, and V received 1000, 3000 and 6000 IU/kg of cholecalciferol, respectively by oral gavage, and concurrently with CoCl2. Cobalt-treated rats showed neuronal vacuolation and presence of pyknotic nuclei in the cerebral cortex and hippocampus, depletion of Purkinje cells in the cerebellum, as well as inflammation and congestion in the intestinal mucosa. Cobalt also increased brain and intestinal hydrogen peroxide (H2O2) and malondialdehyde (MDA) concentrations, while simultaneously reducing glutathione (GSH) content, superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione S-transferase (GST) activities. Further, CoCl2 induced increases in brain acetylcholinesterase (AchE) activity and serum zonulin (ZO-1) levels. Conversely, Cho administration suppressed CoCl2-induced damages in the brain and intestines by reducing lipid peroxidation and increasing the activities of antioxidant enzymes. Remarkably, Cho produced stimulation of brain choline acetyltransferase (ChAT) and suppression of AchE activity, along with dose-dependent reduction in serum levels of ZO-1, intestinal fatty acid-binding protein (iFABP) and nitric oxide. In conclusion, the protective role of cholecalciferol against cobalt-induced toxicity occurred via modulation of cholinergic, intestinal permeability and antioxidant pathways. The results may prove significant in the context of the role of gut-brain connections in neuroprotection.

Vinpocetine attenuates methotrexate-induced hippocampal intoxication via Keap-1/Nrf2, NF-κB/AP-1, and apoptotic pathways in rats

Methotrexate (MTX) is an anti-folate chemotherapeutic commonly used to treat cancer and autoimmune diseases. Despite its widespread clinical use, MTX has been linked to serious neurotoxicity side effects. Vinpocetine (VNP) has been widely used clinically to treat many neurological conditions. This study was conducted to study the potential neuroprotective effects of VNP against MTX hippocampal intoxication in rats. Thirty-two rats were randomly allocated into 4 groups: (I) control (Vehicle); (II) VNP-treated group (20 mg/kg/day, p.o); (III) MTX-control (20 mg/kg/once, i.p.) group; and (IV) the VNP + MTX group. VNP was administered orally for 10 days, during which MTX was given intraperitoneally once at the end of day 5. Our data indicated that VNP administration significantly improved MTX-induced neuronal cell death, odema, vacuolation and degeneration. VNP attenuated oxidative injury mediated by significant upregulation of the Nrf2, HO-1, and GCLC genes, while the Keap-1 mRNA expression downregulated. Moreover, VNP suppressed cytokines release mediated by increasing IκB expression level while it caused a marked downregulation in NF-κB and AP-1 (C-FOS and C-JUN) levels. Additionally, VNP attenuated apoptosis by reducing hippocampal Bax levels while increasing Bcl2 levels in MTX-intoxicated rats. In conclusion, our results suggested that VNP significantly attenuated MTX hippocampal intoxication by regulating Keap-1/Nrf2, NF-κB/AP-1, and apoptosis signaling in these effects.

The impact of VPS35 D620N mutation on alternative autophagy and its reversal by estrogen in Parkinson's disease

VPS35 plays a key role in neurodegenerative processes in Alzheimer’s disease and Parkinson’s disease (PD). Many genetic studies have shown a close relationship between autophagy and PD pathophysiology, and specifically, the PD-causing D620N mutation in VPS35 has been shown to impair autophagy. However, the molecular mechanisms underlying neuronal cell death and impaired autophagy in PD are debated. Notably, increasing evidence suggests that Rab9-dependent “alternative” autophagy, which is driven by a different molecular mechanism that driving ATG5-dependent “conventional” autophagy, also contributes to neurodegenerative process. In this study, we investigated the relationship between alternative autophagy and VPS35 D620N mutant-related PD pathogenesis. We isolated iPSCs from the blood mononuclear cell population of two PD patients carrying the VPS35 D620N mutant. In addition, we used CRISPR-Cas9 to generate SH-SY5Y cells carrying the D620N variant of VPS35. We first revealed that the number of autophagic vacuoles was significantly decreased in ATG5-knockout Mouse Embryonic Fibroblast or ATG5-knockdown patient-derived dopaminergic neurons carrying the VPS35 D620N mutant compared with that of the wild type VPS35 control cells. Furthermore, estrogen, which activates alternative autophagy pathways, increased the number of autophagic vacuoles in ATG5-knockdown VPS35 D620N mutant dopaminergic neurons. Estrogen induces Rab9 phosphorylation, mediated through Ulk1 phosphorylation, ultimately regulating alternative autophagy. Moreover, estrogen reduced the apoptosis rate of VPS35 D620N neurons, and this effect of estrogen was diminished under alternative autophagy knockdown conditions. In conclusion, alternative autophagy might be important for maintaining neuronal homeostasis and may be associated with the neuroprotective effect of estrogen in PD with VPS35 D620N.

Monocyte chemoattractant protein-1 and cyclooxygenase enzymes in rats treated with drugs of abuse

The CC chemokine monocyte chemoattractant protein (MCP)-1/CCL2 and cyclo-oxygenase-2 enzyme are potent mediators of neuroinflammation. We studied the effect of treatment with Cannabis sativaresin extract and/or tramadol, two common drugs of abuse on the level of MCP-1 in brain and serum of rats. In addition, serum levels of cyclo-oxygenase 1 (COX-1) and cyclo-oxygenase 2 (COX-2) enzymes in rats given cannabis werealso determined. Cannabis sativaresin at 5, 10 or 20 mg/kg (expressed as delta-9-tetrahydrocannabinol), tramadol at 5, 10 or 20 mg/kg or tramadol at 10 mg/kg combined with cannabis at 5-20 mg/kg were given once a day, subcutaneously, for six weeks. Resultsshowed that, as compared to corresponding controls, Cannabis sativa resin produced a significant increase in MCP-1 increased inbrain tissue (29.8-56.4%) and serum (14.8-31.0%). MCP-1 showed also significant increments in brain (34.6%) and serum (22.1%) by 20 mg/kg tramadol. After the concomitant treatment with both cannabis and tramadol, MCP-1 increased in brainby 88.5-145.7%and in serum by 32.6-64.8%. Moreover, cannabis given at 20 mg/kg significantly increasedserum COX-1 and COX-2 by 362% and 58.8% compared to corresponding control values. The histopathological study of the striatum of cannabis-treated animals revealed the presence of apoptotic cells and pyknotic nuclei and congestion of blood vessels. The striatum from animals given tramadol showed neuronal perinuclear cytoplasmic vacuolations and apoptotic cells. Moreover, the combined administration of both cannabis and tramadol resulted in neuronal necrosis, vacuolation, apoptosis and pyknosis. Collectively, these results indicate that treatment with cannabis resin and/or tramadol is associated with a proinflammatory response that involves MCP-1 and cyclooxygenases and which could result in the development of brain injury.

Subchronic Arsenic Exposure Induces Behavioral Impairments and Hippocampal Damage in Rats.

This study investigated the effects of subchronic arsenic exposure on behavior, neurological function, and hippocampal damage in rats. Thirty-two male Wistar rats were divided into four groups and exposed to different concentrations of arsenic in their drinking water for 12 weeks, while weekly water intake and body weight were recorded. Various neurobehavioral tests were conducted, evaluating overall activity levels, exploratory behavior, short-term memory, spatial learning and memory, anxiety-like behavior, and depressive-like states. Arsenic levels in urine, serum, and brain tissue were measured, and histopathological analysis assessed hippocampal damage using hematoxylin and eosin staining. The results demonstrated that arsenic exposure did not significantly affect overall activity or exploratory behavior. However, it impaired short-term memory and spatial learning and memory functions. Arsenic-exposed rats exhibited increased anxiety-like behavior and a depressive-like state. Arsenic levels increased dose-dependently in urine, serum, and brain tissue. The histopathological examinations revealed significant hippocampal damage, including neuronal shrinkage, cell proliferation, irregular structure, disordered arrangement, and vacuolation. These findings emphasize the importance of understanding the impact of arsenic exposure on behavior and brain health, highlighting its potential neurological consequences.

Arsenic induced neurotoxicity in the brain of ducks: The potential involvement of the gut-brain axis

BackgroundArsenic is a widely distributed ecotoxic pollutant that has been found to cause neurotoxicity in a variety of species. Gut-brain axis is a two-way information network between the gut microbiome and the brain, which is closely related to organismal health. However, the role of the gut-brain axis in arsenic-induced neurotoxicity remains largely unknown. MethodsIn order to explore whether there is a relationship between brain and gut microbiota of meat ducks, we performed molecular biological detection including RT-qPCR and Western blot, as well as morphological detection including, HE staining and immunohistochemistry. Meanwhile, intestinal contents were analyzed using 16 S ribosomal RNA gene sequencing and analysis ResultsIn this study, we investigated whether arsenic trioxide (ATO) can activate the gut microbiome-brain axis to induce intestinal and brain injury. The results showed that ATO-exposure disrupted the diversity balance of intestinal microbiota and integrity and injured the intestinal structure. ATO-exposure also reduced the number of glycogen and goblet cells in the duodenum. In addition, exposure to ATO caused intestinal inflammatory injury by activating NF-κB signaling pathway and promoting the expression of its target genes. Meanwhile, the tight junction-related proteins (ZO-1, occludin) of gut and brain were reduced by ATO exposure. Furthermore, results also revealed that ATO-exposure induced brain injury, including neuronal cell vacuolization and reduced numbers of neuronal cells in the cortex and hippocampus. Remarkably, ATO-exposure also disrupted neurotransmitter levels. Additionally, our further molecular mechanism study revealed that ATO-exposure increased the expression of autophagy and apoptosis related mRNA and proteins levels in the brain tissues. ConclusionAltogether, these findings provide a new insight into that ATO-exposure induced intestinal injury and aggravated neurotoxicity via the gut-brain axis.

The extract of Sclerocarya birrea, Nauclea latifolia, and Piper longum mixture ameliorates diabetes-associated cognitive dysfunction.

Diabetes-associated cognitive dysfunction is linked to chronic hyperglycemia, oxidative stress, inflammation, cholinergic dysfunction, and neuronal degeneration. We investigated the antidiabetic and neuroprotective activity of a mixture of Sclerocarya birrea, Nauclea latifolia, and Piper longum (SNP) in type 2 diabetic (T2D) rat model-induced memory impairment. Fructose (10%) and streptozotocin (35mg/kg) were used to induce T2D in male Wistar rats. Diabetic animals received distilled water, metformin (200mg/kg), or SNP mixture (75, 150, or 300mg/kg). HPLC-MS profiling of the mixture was performed. Behavioral testing was conducted using the Y-maze, NORT, and Morris water mazes to assess learning and memory. Biochemical markers were evaluated, including carbohydrate metabolism, oxidative/nitrative stress, pro-inflammatory markers, and acetylcholinesterase activity. Histopathological examination of the pancreas and hippocampus was also performed. Fructose/STZ administration resulted in T2D, impaired short- and long-term memory, significantly increased oxidative/nitrative stress, pro-inflammatory cytokine levels, acetylcholinesterase activity (AChE), hippocampal neuronal loss and degeneration in CA1 and CA3 subfields, and neuronal vacuolation in DG. SNP mixture at 150 and 300mg/kg significantly improved blood glucose and memory function in diabetic rats. The mixture reduced oxidative/nitrative stress and increased endogenous antioxidant levels. It also reduced serum IL-1β, INF-γ and TNF-α levels and ameliorated AChE activity. Histologically, SNP protected hippocampus neurons against T2D-induced neuronal necrosis and degeneration. We conclude that the aqueous extract of SNP mixture has antidiabetic and neuroprotective activities thanks to active metabolites identified in the plant mixture, which consequently normalized blood glucose, protected hippocampus neurons, and improved memory function in diabetic rats.

Diclofenac sodium and dexamethasone co-therapy restores brain neuron-specific enolase (NSE), S-100 Beta and glial fibrillary acid protein (GFAP) proteins in experimental rat's model: A possible inhibition of P-glycoprotein.

Non-steroidal anti-inflammatory drugs decrease pain and fever while corticosteroids regulate inflammation and immune response, both are prescribed to reduce inflammation and control pain. The present study aimed to study the effects of their monotherapy and co-administration on the brain tissue structure of experimental rats. P-glycoprotein (PGP), a transporter membrane protein, plays an important role in various physiological and physio-pathological conditions, drug-drug and drug-food interactions, and multi-drug resistance. Male rats were divided into four groups and received normal saline, dexamethasone, diclofenac sodium and their dual therapy respectively, then after one-month rats were sacrificed and brain tissues proceeded for hematoxylin and eosin staining to study their histopathology and immunohistochemically staining of NSE, S100-B and GFAP biomarkers were performed. Additionally, in silico molecular docking studies were conducted to elucidate interactions between PGP and used compounds. Resultsshowed that dexamethasone or diclofenac sodium treatments showed abnormalities like edema, neuronal vacuoles, astrocytes hyperplasia and microglial cells with positive reaction to NSE, S100 and GFAP antibodies while the dual therapy displayed less edema and other signs of damage with negative and weak positive staining of NSE, S100 and GFAP antibodies respectively. The molecular docking showed that there were different affinities toward the involved PGP active site. These interaction results were great with Dexamethasone -9.6 kcal/mol forming hydrophobic interactions with the highest affinity when compared with Diclofenac sodium which gave -8.4 kcal/mol. In conclusion, the side effects of the two types of anti-inflammatory drugs may be minimized through their interactions. However, Molecular Dynamic Simulations studies are required to explain the exact dynamic behaviors and protein-ligand stability.

Bovine autosomal recessive alpha‐mannosidosis in an Aberdeen Angus herd from Argentina

AbstractAn outbreak of α‐mannosidosis in a bovine herd from Buenos Aires province is reported. Postmortem examination, histology, lectin histochemistry and electron microscopy were performed on five calves born with nervous signs. Hair samples from dams and calves were genetically analysed. The α‐mannosidase gene including exon 7 was amplified and sequenced. At postmortem examination, no gross changes were evident. Histologically, cytoplasmic neuronal vacuolation in the brain and cerebellum of the five calves, staining moderately to intensively, with lectin histochemistry was evident. Ultrastructurally, vacuoles containing finely granulated material in the cytoplasm of neurons, myelin degeneration and axonal swelling were seen in the brain. Genetic analysis revealed a heterozygous carrier state for 961T→C transition in the exon 7 of α‐mannosidosis gene of four cows, and a recessive homozygous state for 961T→C transition in the same genes in the calves analysed. This highlights the importance of identifying and removing animals carrying the α‐mannosidosis mutated gene.

Implication of Wnt/GSK-3β/β-Catenin Signaling in the Pathogenesis of Mood Disturbances Associated with Hyperthyroidism in Rats: Potential Therapeutic Effect of Naringin.

Patients with hyperthyroidism are commonly diagnosed with mood disorders. Naringin, (4',5,7-trihydrocyflavanone-7-O-rhamnoglucoside), a natural bioflavonoid, has many neurobehavioral activities including anxiolytic and antidepressant properties. The role of Wingless (Wnt) signaling in psychiatric disorders is considered substantial but debatable. Recently, regulation of Wnt signaling by naringin has been reported in different disorders. Therefore, the present study aimed to investigate the possible role of Wnt/GSK-3β/β-catenin signaling in hyperthyroidism-induced mood disturbances and explore the therapeutic effects of naringin. Hyperthyroidism was induced in rats by intraperitoneal injection of 0.3 mg/kg levothyroxine for 2 weeks. Naringin was orally administered to rats with hyperthyroidism at a dose of 50 or 100 mg/kg for 2 weeks. Hyperthyroidism induced mood alterations as revealed by behavioral tests and histopathological changes including marked necrosis and vacuolation of neurons in the hippocampus and cerebellum. Intriguingly, hyperthyroidism activated Wnt/p-GSK-3β/β-catenin/DICER1/miR-124 signaling pathway in the hippocampus along with an elevation in serotonin, dopamine, and noradrenaline contents and a reduction in brain-derived neurotrophic factor (BDNF) content. Additionally, hyperthyroidism induced upregulation of cyclin D-1 expression, malondialdehyde (MDA) elevation, and glutathione (GSH) reduction. Naringin treatment alleviated behavioral and histopathological alterations and reversed hyperthyroidism-induced biochemical changes. In conclusion, this study revealed, for the first time, that hyperthyroidism could affect mental status by stimulating Wnt/p-GSK-3β/β-catenin signaling in the hippocampus. The observed beneficial effects of naringin could be attributed to increasing hippocampal BDNF, controlling the expression of Wnt/p-GSK-3β/β-catenin signaling as well as its antioxidant properties.

Oligodendroglia Confer Neuroprotection to NSC-34 Motor Neuronal Cells Against the Toxic Insults of Cerebrospinal Fluid from Sporadic Amyotrophic Lateral Sclerosis Patients.

Amyotrophic lateral sclerosis (ALS) is a complex neurodegenerative disorder with multifactorial pathomechanisms affecting not only motor neurons but also glia. Both astrocytes and microglia get activated and contribute significantly to neurodegeneration. The role of oligodendroglia in such a situation remains obscure, especially in the sporadic form of ALS (SALS), which contributes to 90% of cases. Here, we have investigated the role of oligodendroglia in SALS pathophysiology using a human oligodendroglial cell line, MO3.13, by exposing the cells to cerebrospinal fluid from SALS patients (ALS-CSF; 10% v/v for 48 h). ALS-CSF significantly reduced the viability of MO3.13 cells and down-regulated the expression of oligodendroglia-specific proteins, namely, CNPase and Olig2. Furthermore, to investigate the effect of the observed oligodendroglial changes on motor neurons, NSC-34 motor neuronal cells were co-cultured/supplemented with conditioned/spent medium of MO3.13 cells upon exposure to ALS-CSF. Live cell imaging experiments revealed protection to NSC-34 cells against ALS-CSF toxicity upon co-culture with MO3.13 cells. This was evidenced by the absence of neuronal cytoplasmic vacuolation and beading of neurites, which instead resulted in better neuronal differentiation. Enhanced lactate levels and increased expression of its transporter, MCT-1, with sustained expression of trophic factors, namely, GDNF and BDNF, by MO3.13 cells hint towards metabolic and trophic support provided by the surviving oligodendroglia. Similar metabolic changes were seen in the lumbar spinal cord oligodendroglia of rat neonates intrathecally injected with ALS-CSF. The findings indicate that oligodendroglia are indeed rescuer to the degenerating motor neurons when the astrocytes and microglia turn topsy-turvy.

Does lithium poisoning induce brain injuries?-A histopathological rat study.

Due to a narrow therapeutic index, prolonged lithium treatment and overdose may result in neurotoxicity. Neurotoxicity is deemed reversible with lithium clearance. However, echoing the report of syndrome of irreversible lithium-effectuated neurotoxicity (SILENT) in rare severe poisonings, lithium-induced histopathological brain injuries including extensive neuronal vacuolization, spongiosis and ageing-like neurodegenerative changes were described in the rat following acute toxic and pharmacological exposure. We aimed to investigate the histopathological consequences of lithium exposure in rat models mimicking prolonged treatment and all three patterns of acute, acute-on-chronic and chronic poisonings observed in humans. We performed histopathology and immunostaining-based analyses using optic microscopy of brains obtained from male Sprague-Dawley rats randomly assigned to lithium or saline (controls) and treated according to the therapeutic or to the three poisoning models. No lesion was observed in any brain structure in any of the models. Neuron and astrocyte counts did not differ significantly between lithium-treated rats and controls. Our findings support that lithium-induced neurotoxicity is reversible and brain injury not a common feature of toxicity.

Silymarin Encapsulated Liposomal Formulation: An Effective Treatment Modality against Copper Toxicity Associated Liver Dysfunction and Neurobehavioral Abnormalities in Wistar Rats.

Wilson's disease causes copper accumulation in the liver and extrahepatic organs. The available therapies aim to lower copper levels by various means. However, a potent drug that can repair the damaged liver and brain tissue is needed. Silymarin has hepatoprotective, antioxidant, and cytoprotective properties. However, poor oral bioavailability reduces its efficacy. In this study, a "thin film hydration method" was used for synthesizing silymarin-encapsulated liposome nanoparticles (SLNPs) and evaluated them against copper toxicity, associated liver dysfunction and neurobehavioral abnormalities in Wistar rats. After copper toxicity induction, serological and behavioral assays were conducted to evaluate treatment approaches. Histological examination of the diseased rats revealed severe hepatocyte necrosis and neuronal vacuolation. These cellular degenerations were mild in rats treated with SLNPs and a combination of zinc and SLNPs (ZSLNPs). SLNPs also decreased liver enzymes and enhanced rats' spatial memory significantly (p = 0.006) in the diseased rats. During forced swim tests, SLNPs treated rats exhibited a 60-s reduction in the immobility period, indicating reduced depression. ZSLNPs were significantly more effective than traditional zinc therapy in decreasing the immobility period (p = 0.0008) and reducing liver enzymes, but not in improving spatial memory. Overall, SLNPs enhanced oral silymarin administration and managed copper toxicity symptoms.

Experimental bovine spongiform encephalopathy infection in rabbits

The aim of our work was to determine the sensitivity of rabbits to the C-BSE pathogen in the first passage, to obtain a laboratory model on rabbits to study the C-BSE pathogen. The results of the experiments showed that with intracerebral infection of rabbits with the causative agent of classical spongiform encephalopathy of cows (C-BSE) they are 100% sensitive to the pathogen with an incubation period of 570 to 1842 days. The disease proceeds with the development of a clinical picture typical of prion diseases, the development of pathomorphological changes in the central nervous system in the form of vacuolization of neurons and neuropiles in various parts of the brain and massive deposition of prion protein PrPSc both in brain tissues and in peripheral lymphoid tissue (spleen). The laboratory model on rabbits is a highly sensitive model for studying the prion of bovine spongiform encephalopathy (C-BSE) and probably the causative agent of v-CJD.

HYPOBARIC HYPOXIA CAUSING HISTOMORPHOLOGICAL ALTERATIONS IN DIFFERENT PARTS OF THE RAT'S BRAIN

Hypobaric hypoxia causes degenerative changes in different parts of the brain, which leads to the formation of cerebral edema. This study aimed to investigate the morphohistological changes in the brain of rats exposed to hypobaric hypoxia. In particular, the hippocampus, cerebral cortex, and striatum were studied. Animals were exposed to hypobaric hypoxia for 10 days. Histomorphological examination showed degenerative changes in the hippocampus, dentate gyrus, and striatum, accompanied by pyknosis of neuronal nuclei, cytoplasmic vacuolization, and neuronal shrinkage, while the cortex of the large hemispheres remained almost intact. Histological studies showed that different parts of the brain respond to hypoxic conditions with different manifestations.

Imidacloprid induced growth, hematological, neuro-behavior, anti-oxidant, economic, genetic, and histopathological alterations in Clarias gariepinus: Alleviative role of dietary Hyphaene thebaica

The current study was a pioneer attempt to explore the toxicological impacts of imidacloprid (IMI) pesticide and to investigate the efficiency of Hyphaene thebaica fruit (HTF) as a dietary supplement in attenuating the IMI effect in African catfish (Clarias gariepinus). Fish were sampled after 2 months of exposure to IMI (1/5 LC50: nominal 2.03 μg/L) and HTF (15 g/kg diet) supplementation, in combination or individually. Growth, hematological, stress, and antioxidant indicators, besides the mRNA expression of various genes in gills tissues and immunohistochemical and economic parameters, were assessed. The outcomes demonstrated that IMI exposure induced behavioral changes, and a significant decrease (p < 0.05) in the majority of the measured variables including growth, hematology, economic efficiency, neurotransmitter (acetylcholine esterase), glucose level, and antioxidant capacity (catalase, and superoxide dismutase (SOD)). Additionally, IMI dysregulated the expression of tumor necrosis factor-alpha (TNF-α), Toll-like receptor 5 (TLR-5), Toll-like receptor 1 (TLR-1), lysozyme C (LYSC), lysozyme G (LYSG), transforming growth factor-beta (TGF-β), myeloperoxidase (MYE), CXC chemokine (CXC), heat shock proteins 90 (HSP90), and SOD1 in the gills. On the other hand, marked increases in the serum malondialdehyde and stress indicator (cortisol) with the highest mortality losses were detected in IMI-exposed fish. Histopathological disorders are detected in the brain post-exposure to IMI including marked neuronal vacuolation, neuronophagia, and complete neuronal loss with weak BCL-2 and marked caspase-3 immunoreactivity. The dietary intervention with HTF revealed a noticeable modulation in the aforementioned parameters and regeneration in the histological architecture. Taken together, the IMI induces severe stress, and behavioral and histological alterations, and impairs the C. gariepinus growth, economic efficiency, and hematological, and antioxidant efficacy through the negative transcriptional impact on the associated genes. Nevertheless, the dietary HTF (15 g/kg diet) could be utilized as a potential natural growth promoter, antioxidant modulator, and against IMI hazards for sustaining aquaculture.