Parkinson's disease (PD) is a common neurodegenerative disorder mainly related to mitochondrial dysfunction of dopaminergic neurons in the midbrain substantia nigra. This study aimed to investigate the effects of exercise preconditioning on motor deficits and mitochondrial function in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse model. Eight-week-old male C57BL/6J mice were randomly divided into four groups: sedentary + saline (SS), sedentary + MPTP (SM), exercise + saline (ES), and exercise + MPTP (EM) groups. Mice in the ES and EM groups received 4 weeks of treadmill training, and then SM and EM groups were treated with MPTP for 5 days. Motor function was assessed by behavioral tests, and morphological and functional changes in dopaminergic neurons and mitochondria in the substantia nigra of the midbrain were evaluated using immunohistochemistry, Western blot, and transmission electron microscopy technology. The results showed that, compared with the SM group, the EM group exhibited significantly improved motor ability, up-regulated protein expression levels of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the midbrain, and down-regulated protein expression of α-synuclein (α-Syn) in the mitochondria of substantia nigra. Compared with the SM group, the EM group showed up-regulated protein expression levels of mitochondrial fusion proteins, including optical atrophy protein 1 (OPA1) and mitofusin 2 (MFN2), and biogenesis-related proteins, including peroxisome proliferator activated receptor gamma coactivator 1α (PGC-1α) and mitochondrial transcription factor A (TFAM), while the protein expression levels of dynamin-related protein 1 (DRP1) and mitochondrial fission protein 1 (FIS1) were significantly down-regulated. Compared with the SM group, the EM group showed significantly reduced damage to substantia nigra mitochondria, restored mitochondrial membrane potential and ATP production, and decreased levels of reactive oxygen species (ROS). These results suggest that 4-week treadmill pre-training can alleviate MPTP-induced motor impairments in PD mice by improving mitochondrial function, providing a theoretical basis for early exercise-based prevention of PD.
Animals ; Male ; Physical Conditioning, Animal/physiology* ; Mice ; Mice, Inbred C57BL ; Mitochondria/physiology* ; Dopaminergic Neurons ; MPTP Poisoning/physiopathology* ; Substantia Nigra ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine

BACKGROUND: Methylmercury (MeHg) causes damage specifically in cerebrocortical neurons, but not in hippocampal neurons. In our previous studies using cultured neurons, we found that brain-derived neurotrophic factor (BDNF), which is prominently present in hippocampal neurons, plays a key role in resistance to MeHg neurotoxicity. Our findings, combined with recent findings that moderate exercise increases BDNF in the brain, led us to hypothesize that moderate exercise protects against MeHg-induced neurotoxicity by inducing BDNF expression. METHODS: C57 black 6NJcl (C57BL/6NJcl) male mice were used to evaluate the effects of treadmill exercise (a moderate exercise) on the neurotoxicity of MeHg exposure at 1.5 mg/kg/day. The effects of treadmill exercise on MeHg neurotoxicity were evaluated through neurobehavioral, neuropathological, and biochemical analyses using brain tissue, blood, and muscle tissue. RESULTS: Treadmill exercise had a significant inhibitory effect on the neurological symptoms associated with apoptotic neuronal death and subsequent cerebrocortical neuron loss induced by MeHg exposure. In the cerebral cortex, treadmill exercise significantly increased BDNF levels and activated the neuroprotective-related BDNF-tropomyosin receptor kinase (Trk) B and p44/42 mitogen-activated protein kinase (MAPK) pathways along with significantly suppressing the neuronal cell death-associated p38 MAPK pathway. Furthermore, treadmill exercise significantly increased fibronectin type III domain containing 5 (FNDC5) expression in the muscle tissue and elevated ed the concentration of its metabolite, irisin, in the blood. CONCLUSIONS These results suggest that treadmill exercise increases BDNF in the brain and suppresses neurotoxic pathways, ultimately protecting against MeHg neurotoxicity. Moreover, the increase of BDNF in the brain may be attributed to the exercise-induced increased expression of FNDC5 in muscle tissue from where it is released into the blood as irisin and finally transferred into the brain and promoted BDNF production.
Animals ; Brain-Derived Neurotrophic Factor/genetics* ; Methylmercury Compounds/toxicity* ; Male ; Mice ; Mice, Inbred C57BL ; Physical Conditioning, Animal ; Brain/drug effects* ; Neurotoxicity Syndromes/prevention & control*

The primary intravenous anesthetics employed in clinical practice encompass dexmedetomidine (Dex), propofol, ketamine, etomidate, midazolam, and remimazolam. Apart from their established sedative, analgesic, and anxiolytic properties, an increasing body of research has uncovered neuroprotective effects of intravenous anesthetics in various animal and cellular models, as well as in clinical studies. However, there also exists conflicting evidence pointing to the potential neurotoxic effects of these intravenous anesthetics. The role of intravenous anesthetics for neuro on both sides of protection or toxicity has been rarely summarized. Considering the mentioned above, this work aims to offer a comprehensive understanding of the underlying mechanisms involved both in the central nerve system (CNS) and the peripheral nerve system (PNS) and provide valuable insights into the potential safety and risk associated with the clinical use of intravenous anesthetics.
Animals ; Humans ; Anesthetics, Intravenous/adverse effects* ; Neuroprotective Agents/pharmacology* ; Propofol ; Neurotoxicity Syndromes/prevention & control* ; Central Nervous System/drug effects* ; Dexmedetomidine

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a severe dose-limiting adverse event of chemotherapy. Presently, the mechanism underlying the induction of CIPN remains unclear, and no effective treatment is available. In this study, through metabolomics analyses, we found that nab-paclitaxel therapy markedly increased serum serotonin [5-hydroxtryptamine (5-HT)] levels in both cancer patients and mice compared to the respective controls. Furthermore, nab-paclitaxel-treated enterochromaffin (EC) cells showed increased 5-HT synthesis, and serotonin-treated Schwann cells showed damage, as indicated by the activation of CREB3L3/MMP3/FAS signaling. Venlafaxine, an inhibitor of serotonin and norepinephrine reuptake, was found to protect against nerve injury by suppressing the activation of CREB3L3/MMP3/FAS signaling in Schwann cells. Remarkably, venlafaxine was found to significantly alleviate nab-paclitaxel-induced CIPN in patients without affecting the clinical efficacy of chemotherapy. In summary, our study reveals that EC cell-derived 5-HT plays a critical role in nab-paclitaxel-related neurotoxic lesions, and venlafaxine co-administration represents a novel approach to treating chronic cumulative neurotoxicity commonly reported in nab-paclitaxel-based chemotherapy.
Paclitaxel/toxicity* ; Animals ; Albumins/adverse effects* ; Serotonin/metabolism* ; Mice ; Humans ; Male ; Female ; Venlafaxine Hydrochloride/therapeutic use* ; Neurotoxicity Syndromes/metabolism* ; Middle Aged ; Schwann Cells/metabolism* ; Peripheral Nervous System Diseases/drug therapy* ; Antineoplastic Agents

The study explored the pathological mechanism of doxorubicin chemotherapy-induced neurotoxicity and the intervention methods of traditional Chinese medicine. BALB/c mice were selected to establish tumor-bearing mouse models by orthotopic injection of 4T1 triple-negative breast cancer cells. After randomization, the mice were treated with doxorubicin chemotherapy or doxorubicin chemotherapy + Kaixin San(KXS). The lesions in the prefrontal cortex of mice were observed by pathological examination, and the lesion information was obtained by long non-coding RNA sequencing. The occurrence of lesions was determined by Western blot and biochemical indicators. In addition, neuroblastoma cells and microglia cells were used to construct in vitro models, and drug-containing serum and p-AMPK dephosphorylation inhibitors were used to further verify the accuracy of animal experiments. Pathological results showed that KXS could alleviate doxorubicin-induced neuronal degeneration in the prefrontal cortex. The long non-coding RNA sequencing suggested that neuronal degeneration and the intervention process of KXS were related to ferroptosis, immune diseases, AMPK signaling pathway, etc. Western blot and biochemical indicators confirmed that this process was directly related to the activation of the AMPK/HIF-1α/ACSL4 signaling pathway to alleviate ferroptosis of neurons and immune response of glial cells. In conclusion, KXS could alleviate doxorubicin-induced neurotoxicity by activating the AMPK signaling pathway and reducing the ferroptosis of neurons and immune response of glial cells.
Animals ; Doxorubicin/toxicity* ; Mice ; AMP-Activated Protein Kinases/genetics* ; Signal Transduction/drug effects* ; Mice, Inbred BALB C ; Drugs, Chinese Herbal/administration & dosage* ; Female ; Humans ; Cell Line, Tumor ; Neurotoxicity Syndromes/genetics*

It has been confirmed that exposure to various metal pollutants can induce neurotoxicity, which is closely associated with the occurrence and development of neurological disorders. Ferroptosis is a form of cell death in response to metal pollutant exposure and it is closely related to oxidative stress, iron metabolism and lipid peroxidation. Recent studies have revealed that ferroptosis plays a significant role in the neurotoxicity induced by metals such as lead, cadmium, manganese, nickel, and antimony. Lead exposure triggers ferroptosis through oxidative stress, iron metabolism disorder and inflammation. Cadmium can induce ferroptosis through iron metabolism, oxidative stress and ferroptosis related signaling pathways. Manganese can promote ferroptosis through mitochondrial dysfunction, iron metabolism disorder and oxidative stress. Nickel can promote ferroptosis by influencing mitochondrial function, disrupting iron homeostasis and facilitating lipid peroxidation in the central nervous system. Antimony exposure can induce glutathione depletion by activating iron autophagy, resulting in excessive intracellular iron deposition and ultimately causing ferroptosis. This article reviews the effects of metal pollutants on ferroptosis-related indicators and discusses the specific mechanisms by which each metal triggers ferroptosis. It provides a reference for identifying targets for preventing neurotoxicity and for developing treatment strategies for neurological disorders.
Ferroptosis/drug effects* ; Humans ; Iron/metabolism* ; Oxidative Stress/drug effects* ; Neurotoxicity Syndromes/metabolism* ; Cadmium/adverse effects* ; Animals ; Lipid Peroxidation/drug effects* ; Metals/metabolism* ; Lead/adverse effects* ; Environmental Pollutants/toxicity* ; Manganese/adverse effects* ; Nickel/adverse effects* ; Mitochondria/drug effects* ; Signal Transduction/drug effects*

In this paper, the MRI manifestations of 15 patients with benzene toxic encephalopathy were analyzed, and the lesion location, shape, scope and signal were observed. The clinical manifestations of 15 patients were mainly central nervous system damage, and the MRI manifestations were characteristic, with a wide range of lesions, and the shapes were "sunflower-like", "flame-like", "bracket-like" and "butterfly-like", and the MRI signal was sheet-like long T(1), long T(2), fluid attenuated inversion recovery (FLAIR) sequence and diffusion weighted imaging (DWI) high signal, apparent diffusion coeffecient (ADC) map low, equal or high signals. When the patient's diagnosis is unclear, MRI examination may provide clinical basis for diagnosis.
Benzene ; Diffusion Magnetic Resonance Imaging/methods* ; Humans ; Magnetic Resonance Imaging ; Neurotoxicity Syndromes/etiology*

Objective: To investigate the implementation of Diagnostic Criteria of Occupational Acute Neurotoxic Diseases Caused by Chemicals (GBZ 76-2002) for accumulating basis of standard revision. Methods: In February 2020, 85 experts in occupational diseases and neurology from 39 medical and health institutions were selected as the respondents. The modified Delphi method was used to establish the standard evaluation index system and special group was organized for discussing the pre-survey and completing the questionnaire survey. Questionnaire survey was performed to investigate the grasp of the standards, application and modification suggestions of respondents. Results: The respondents' mastery of standard-related knowledge mainly came from work experience (84.7%, 72/85) , standard learning (81.2%, 69/85) and training (75.3%, 64/85) . Among the institutions in which the respondents worked, 98.8% (84/85) could carry out CT examinations, 96.5% (82/85) could carry out nerve conduction velocity and electromyography examinations, 89.4% (76/85) could carry out EEG examinations, 80% (68/85) could carry out evoked potential examinations and 72.9% (62/85) could carry out MRI examinations. Among the toxicants diagnosed as occupational acute toxic myelopathy, 10.6% (9/85) were organic phosphorus and 9.4% (8/85) were asphyxiating gas; Among the toxicants diagnosed as delayed peripheral neuropathy, pesticides accounted for 25.9% (22/85) and asphyxiating gases accounted for 12.9% (11/85) . 85.9% (73/85) of the respondents believed that the basis for the classification of acute toxic encephalopathy needed to supplement objective evidence; 80.0% (68/85) of the respondents thought that the diagnosis and classification of peripheral neuropathy should be refined according to the abnormal indexes of neuroelectromyography. Conclusion: The applicability of the criteria needs to be improved because the current criteria has a long application cycle without enough objective investigation bases in classification criteria index.
Humans ; Occupational Exposure/adverse effects* ; Occupational Diseases/diagnosis* ; Hazardous Substances ; Neurotoxicity Syndromes/diagnosis* ; Peripheral Nervous System Diseases

Objective: To explore the CT and MRI imaging findings of diquat toxic encephalopathy. Methods: CT and MRI imaging features of 10 patients with diquat poisoning encephalopathy who had been clinically diagnosed were retrospectively reviewed. Results: CT was performed in all 10 patients, and MRI was performed in 8 patients. In 10 patients, 7 had positive signs on CT, and 8 patients with MRI examination had abnormal changes in the images. The main CT findings were symmetrical hypodensity in bilateral cerebellar hemisphere, brainstem, thalamus and basal ganglia, and swelling of brain tissue. The main MRI findings were symmetrical lesions and brain edema in the deep nuclei of cerebellar hemisphere, brainstem, thalamus and basal ganglia, low signal on T1WI, high signal on T2WI and T2-FLAIR, and cytotoxic edema on diffusion weighted imaging (DWI) . On review after treatment, both CT and MRI showed resorption of the lesion, which narrowed in size. Conclusion: The imaging findings of diquat poisoning encephalopathy are characteristic and the location of the lesion is characteristic, and CT and MRI have a certain diagnostic value in diquat poisoning encephalopathy, which is important for clinical treatment.
Brain Diseases ; Diffusion Magnetic Resonance Imaging/methods* ; Diquat ; Humans ; Magnetic Resonance Imaging/methods* ; Neurotoxicity Syndromes/etiology* ; Retrospective Studies

Dioscorea tokoro has long been used in Korean traditional medicine as a pain killer and anti-inflammatory agent. A 53-year-old male who consumed water that had been boiled with raw tubers of D. tokoro as tea presented with numbness and spasm of both hands and feet. Laboratory results showed hypocalcemia, hypoparathyroidism, and vitamin D insufficiency. During his hospital stay, colitis, acute kidney injury, and toxic encephalopathy developed. The patient received calcium gluconate intravenous infusion and oral calcium carbonate with alfacalcidol. His symptoms improved gradually, but hypocalcemia persisted despite the calcium supplementation. We suggest that ingestion of inappropriately prepared D. tokoro can cause symptomatic hypocalcemia in patients with unbalanced calcium homeostasis.
Acute Kidney Injury ; Calcium ; Calcium Carbonate ; Calcium Gluconate ; Colitis ; Dioscorea ; Eating ; Foot ; Hand ; Homeostasis ; Humans ; Hypesthesia ; Hypocalcemia ; Hypoparathyroidism ; Infusions, Intravenous ; Length of Stay ; Male ; Medicine, Korean Traditional ; Middle Aged ; Neurotoxicity Syndromes ; Spasm ; Tea ; Vitamin D ; Water