Lamotrigine(LTG)is a widely used drug for the treatment of epilepsy.Emerging clinical evidence suggests that LTG may improve cognitive function in patients with Alzheimer’s disease.However,the underlying molecular me...Lamotrigine(LTG)is a widely used drug for the treatment of epilepsy.Emerging clinical evidence suggests that LTG may improve cognitive function in patients with Alzheimer’s disease.However,the underlying molecular mechanisms remain unclear.In this study,amyloid precursor protein/presenilin 1(APP/PS1)double transgenic mice were used as a model of Alzheimer’s disease.Five-month-old APP/PS1 mice were intragastrically administered 30 mg/kg LTG or vehicle once per day for 3 successive months.The cognitive functions of animals were assessed using Morris water maze.Hyperphosphorylated tau and markers of synapse and glial cells were detected by western blot assay.The cell damage in the brain was investigated using hematoxylin and eosin staining.The levels of amyloid-βand the concentrations of interleukin-1β,interleukin-6 and tumor necrosis factor-αin the brain were measured using enzyme-linked immunosorbent assay.Differentially expressed genes in the brain after LTG treatment were analyzed by high-throughput RNA sequencing and real-time polymerase chain reaction.We found that LTG substantially improved spatial cognitive deficits of APP/PS1 mice;alleviated damage to synapses and nerve cells in the brain;and reduced amyloid-βlevels,tau protein hyperphosphorylation,and inflammatory responses.High-throughput RNA sequencing revealed that the beneficial effects of LTG on Alzheimer’s disease-related neuropathologies may have been mediated by the regulation of Ptgds,Cd74,Map3k1,Fosb,and Spp1 expression in the brain.These findings revealed potential molecular mechanisms by which LTG treatment improved Alzheimer’s disease.Furthermore,these data indicate that LTG may be a promising therapeutic drug for Alzheimer’s disease.展开更多
Dénes and his co-workers recently published a paper in Nature Neuroscience,documenting that neurological abnormalities in COVID are based on microglial dysfunction in the brain.1 In case of acute respiratory synd...Dénes and his co-workers recently published a paper in Nature Neuroscience,documenting that neurological abnormalities in COVID are based on microglial dysfunction in the brain.1 In case of acute respiratory syndrome of COVID infection,the central nervous system symptomatology significantly contribute to the severity of this disease.The authors used an autopsy platform allowing morphological and biochemical/molecular biological investigations in postmortem mirror blocks prepared from the brain and peripheral organs of 13 COVID and 23 non-COVID-infected patients.展开更多
The development of clinical candidates that modify the natural progression of sporadic Parkinson's disease and related synucleinopathies is a praiseworthy endeavor,but extremely challenging.Therapeutic candidates ...The development of clinical candidates that modify the natural progression of sporadic Parkinson's disease and related synucleinopathies is a praiseworthy endeavor,but extremely challenging.Therapeutic candidates that were successful in preclinical Parkinson's disease animal models have repeatedly failed when tested in clinical trials.While these failures have many possible explanations,it is perhaps time to recognize that the problem lies with the animal models rather than the putative candidate.In other words,the lack of adequate animal models of Parkinson's disease currently represents the main barrier to preclinical identification of potential disease-modifying therapies likely to succeed in clinical trials.However,this barrier may be overcome by the recent introduction of novel generations of viral vectors coding for different forms of alpha-synuclein species and related genes.Although still facing several limitations,these models have managed to mimic the known neuropathological hallmarks of Parkinson's disease with unprecedented accuracy,delineating a more optimistic scenario for the near future.展开更多
The cerebellum is receiving increasing attention for its cognitive,emotional,and social functions,as well as its unique metabolic profiles.Cerebellar microglia exhibit specialized and highly immunogenic phenotypes und...The cerebellum is receiving increasing attention for its cognitive,emotional,and social functions,as well as its unique metabolic profiles.Cerebellar microglia exhibit specialized and highly immunogenic phenotypes under both physiological and pathological conditions.These immune cells communicate with intrinsic and systemic factors and contribute to the structural and functional compartmentalization of the cerebellum.In this review,we discuss the roles of microglia in the cerebellar microenvironment,neuroinflammation,cerebellar adaptation,and neuronal activity,the associated molecular and cellular mechanisms,and potential therapeutic strategies targeting cerebellar microglia in the context of neuroinflammation.Future directions and unresolved questions in this field are further highlighted,particularly regarding therapeutic interventions targeting cerebellar microglia,functional mechanisms and activities of microglia in the cerebellar circuitry,neuronal connectivity,and neurofunctional outcomes of their activity.Cerebellar morphology and neuronal performance are influenced by both intrinsic and systemic factors that are actively monitored by microglia in both healthy and diseased states.Under pathological conditions,local subsets of microglia exhibit diverse responses to the altered microenvironment that contribute to the structural and functional compartmentalization of the cerebellum.Microglia in the cerebellum undergo early maturation during the embryonic stage and display specialized,highly immunogenic phenotypes.In summary,cerebellar microglia have the capacity to serve as regulatory tools that influence outcomes across a wide range of neurological and systemic conditions,including neurodevelopmental,neurodegenerative,metabolic,and stress-related disorders.展开更多
Background:Platinum can cause chemotherapy-related cognitive impairment.Low-intensity focused ultrasound(LIFUS)is a promising noninvasive physical stimulation method with a unique advantage in neurological rehabilitat...Background:Platinum can cause chemotherapy-related cognitive impairment.Low-intensity focused ultrasound(LIFUS)is a promising noninvasive physical stimulation method with a unique advantage in neurological rehabilitation.We aimed to investigate whether LIFUS can alleviate cisplatin-induced cognitive impairment in rats and explore the related neuropatho-logical mechanisms.Methods:After confirming the target position for LIFUS treatment in 18 rats,64 rats were randomly divided into four groups:control,model,sham,and LIFUS groups.Before and after LIFUS treatment,detailed biological behavioral assessments and magnetic resonance imaging were performed.Finally,the rats were euthanized,and relevant histopathological and molecular biological experiments were conducted and analyzed.Results:In the Morris water maze,the model group showed fewer platform crossings(1.250.93 vs.5.691.58),a longer escape latency(41.6536.55 s vs.6.382.11 s),and a lower novel object recognition index(29.7711.83 vs.83.695.67)than the control group.LIFUS treatment improved these metrics,with more platform crossings(3.130.34),a higher recognition index(65.588.71),and a shorter escape latency(6.452.27 s).Longitudinal analysis of the LIFUS group further confirmed these improvements.Neuroimaging revealed significant differences in diffusion tensor imaging metrics of specific brain regions pre-and post-LIFUS.Moreover,neuropathology showed higher dendritic spine density,less myelin loss,fewer apoptotic cells,more synapses,and less mitochondrial autophagy after LIFUS treatment.The neuroimaging indicators were correlated with behavioral improvements,highlighting the potential of LIFUS for alleviating cognitive impairment(as demonstrated through imaging and analysis).Our investigation of the molecular biological mechanisms revealed distinct protein expression patterns in the hippocampus and its subregions.In the model group,glial fibrillary acidic protein(GFAP)and ionized calcium-binding adaptor molecule 1(IBA1)expression levels were elevated across the hippocampus,whereas neuronal nuclei(NeuN)expression was reduced.Subregional analysis revealed higher GFAP and IBA1 and lower NeuN,especially in the dentate gyrus subregion.Moreover,positive cell areas were larger in the cornu ammonis(CA)1,CA2,CA3,and dentate gyrus regions.In the CA2 and CA3,significant differences among the groups were observed in GFAP-positive cell counts and areas,and there were variations in NeuN expression.Conclusions:Our results suggest that LIFUS can reverse cisplatin-induced cognitive impairments.The neuroimaging findings were consistent with the behavioral and histological results and suggest a neuropathological basis that supports further research into the clinical applications of LIFUS.Furthermore,LIFUS appeared to enhance the plasticity of neuronal synapses in the rat hippocampus and reduce hippocampal inflammation.These findings highlight the clinical potential of LIFUS as an effective,noninvasive therapeutic strategy and monitoring tool for chemotherapy-induced cognitive deficits.展开更多
In recent years,a type of extracellular vesicles named exosomes has emerged that play an important role in intercellular communication under physiological and pathological conditions.These nanovesicles (30–150 nm) co...In recent years,a type of extracellular vesicles named exosomes has emerged that play an important role in intercellular communication under physiological and pathological conditions.These nanovesicles (30–150 nm) contain proteins,RNAs and lipids,and their internalization by bystander cells could alter their normal functions.This review focuses on recent knowledge about exosomes as messengers of neuron-glia communication and their participation in the physiological and pathological functions in the central nervous system.Special emphasis is placed on the role of exosomes under toxic or pathological stimuli within the brain,in which the glial exosomes containing inflammatory molecules are able to communicate with neurons and contribute to the pathogenesis of neuroinflammation and neurodegenerative disorders.Given the small size and characteristics of exosomes,they can cross the blood-brain barrier and be used as biomarkers and diagnosis for brain disorders and neuropathologies.Finally,although the application potential of exosome is still limited,current studies indicate that exosomes represent a promising strategy to gain pathogenic information to identify therapeutically targets and biomarkers for neurological disorders and neuroinflammation.展开更多
The current study sought to observe the effects of lead on histological structure and antioxidant capacity in 30-day-old mice.Spectrophotometry was used to detect the activities of superoxide dismutase,catalase,alkali...The current study sought to observe the effects of lead on histological structure and antioxidant capacity in 30-day-old mice.Spectrophotometry was used to detect the activities of superoxide dismutase,catalase,alkaline phosphatase,acid phosphatase and the malondialdehyde content.The results revealed that Purkinje cells in the lead-exposed group exhibited obvious pyknosis,atrophy and a decrease in overall number.Granular cells exhibited a disorderly arrangement,and were reduced in number.Administration of lead decreased the activities of superoxide dismutase,catalase,alkaline phosphatase and acid phosphatase,while malondialdehyde content increased.Two-way analysis of variance indicated that dose contributed more to lead-induced cerebellum damage than treatment time.The present study demonstrated that lead exerted strong effects on histological structure and inhibited antioxidant capacity of the cerebellum in 30-day-old mice.展开更多
The most common age-related neurodegenerative disease is Alzheimer's disease(AD) characterized by aggregated amyloid-β(Aβ) peptides in extracellular plaques and aggregated hyperphosphorylated tau protein in intr...The most common age-related neurodegenerative disease is Alzheimer's disease(AD) characterized by aggregated amyloid-β(Aβ) peptides in extracellular plaques and aggregated hyperphosphorylated tau protein in intraneuronal neurofibrillary tangles,together with loss of cholinergic neurons,synaptic alterations,and chronic inflammation within the brain.These lead to progressive impairment of cognitive function.There is evidence of innate immune activation in AD with microgliosis.Classically-activated microglia(M1 state) secrete inflammatory and neurotoxic mediators,and peripheral immune cells are recruited to inflammation sites in the brain.The few drugs approved by the US FDA for the treatment of AD improve symptoms but do not change the course of disease progression and may cause some undesirable effects.Translation of active and passive immunotherapy targeting Aβ in AD animal model trials had limited success in clinical trials.Treatment with immunomodulatory/anti-inflammatory agents early in the disease process,while not preventive,is able to inhibit the inflammatory consequences of both Aβ and tau aggregation.The studies described in this review have identified several agents with immunomodulatory properties that alleviated AD pathology and cognitive impairment in animal models of AD.The majority of the animal studies reviewed had used transgenic models of early-onset AD.More effort needs to be given to creat models of late-onset AD.The effects of a combinational therapy involving two or more of the tested pharmaceutical agents,or one of these agents given in conjunction with one of the cell-based therapies,in an aged animal model of AD would warrant investigation.展开更多
Objective To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.e.), intraperitoneal (i.p.), intragastrical (i.g.), in...Objective To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.e.), intraperitoneal (i.p.), intragastrical (i.g.), intracardiac and intramuscular (i.m.) approaches. Methods Hamsters were infected with crude- or fine-prepared brain extracts. The neuropathological changes, PrPSc deposits, and patterns of PK-resistant PrP were analyzed by HE stain, immunohistochemistry (IHC) assay and Western blot. Reactive gliosis and neuron loss were evaluated by glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE) specific IHC. Results The animals inoculated in i.m. and Lp. ways with crude PrPSc extracts showed clinical signs at the average incubation of 69.212.8 and 65.5±3.9 days. Inoculation in i.c. and intracardiac ways with fine PrPSc extracts (0.00035 g) caused similar, but relative long incubation of around 90 days. Only one out of eight hamsters challenged in i.g way with low dosage (0.01 g) became ill after a much longer incubation (185 d), while all animals (4/4) with high dosage (0.04 g) developed clinical signs 105 days postinfection. The most remarkable spongiform degeneration and PrPSc deposits were found in brain stem among the five challenge groups generally. The number of GFAP-positive astrocytes increased distinctly in brain stems in all infection groups, while the number of NSE-positive cells decreased significantly in cerebrum, except i.c. group. The patterns of PK-resistant PrP in brains were basically identical among the five infection routes. Conclusion Typical TSE could be induced in hamsters by inoculating strain 263K in the five infection ways. The incubation periods in bioassays depend on infective dosage, administrating pathway and preparation of PrPSc. The neuropathological changes and PrPSc deposits seem to be related with regions and inoculating pathways.展开更多
Attention-deficit/hyperactivity disorder （ADHD） is a neurodevelopmental disorder with a long-term impact on functioning, productivity and quality of life of patients. This impact is largely due to the symptoms of in...Attention-deficit/hyperactivity disorder （ADHD） is a neurodevelopmental disorder with a long-term impact on functioning, productivity and quality of life of patients. This impact is largely due to the symptoms of inattentiveness. However, despite its impairing role in the lives of ADHD patients, inattentiveness has been studied relatively less frequently than have symptoms of impulsivity/hyperactivity and problems with executive function. This review therefore seeks to integrate the neuropsychological theories and current findings in the research fields of neuropsychology, neurophysiology, and neuroimaging, in an attempt to gain a more complete understanding of the role that inattentiveness plays in ADHD, as well as to suggest directions for future studies. The need for a more comprehensive understanding of inattentiveness and ADHD, which integrates findings from each of the three disciplines mentioned above, is emphasized.展开更多
3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer＇s disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain...3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer＇s disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain function of Alzheimer＇s disease remains unclear. In this study, 7.0T magnetic resonance spectroscopy showed that in the hippocampus of Alzheimer＇s disease rats, the N-acetylaspartate wave crest was reduced, and the creatine and choline wave crest was elevated. This finding was further supported by hematoxylin-eosin staining, which showed a loss of hippocampal neurons and more glial cells. Moreover, electron microscopy showed neuronal shrinkage and mitochondrial rupture, and scanning electron microscopy revealed small size hippocampal synaptic vesicles, incomplete synaptic structure, and reduced number. Overall, the results revealed that 7.0T high-field nuclear magnetic resonance spectroscopy detected the lesions and functional changes in hippocampal neurons of Alzheimer＇s disease rats in vivo, allowing the possibility for assessing the success rate and grading of the amyloid beta （1-40） animal model of Alzheimer＇s disease.展开更多
A physiological state of＂normoxia＂obtains when tissue oxygen tension（pO_2）is sufficient to drive mitochondrial respiration throughout a volume of cells.Between 30-40%of the available oxygen is normally extracted f...A physiological state of＂normoxia＂obtains when tissue oxygen tension（pO_2）is sufficient to drive mitochondrial respiration throughout a volume of cells.Between 30-40%of the available oxygen is normally extracted from hemoglobin as it passes through neural tissue.展开更多
Mefloquine is a widely used anti-malarial drug. Some clinical reports suggest that mefloquine may be ototoxic and neurotoxic, but there is little scientific evidence from which to draw any firm conclusion. To evaluate...Mefloquine is a widely used anti-malarial drug. Some clinical reports suggest that mefloquine may be ototoxic and neurotoxic, but there is little scientific evidence from which to draw any firm conclusion. To evaluate the ototoxic and neurotoxic potential of mefloquine, we treated cochlear organotypic cultures and spiral ganglion cultures with various concentrations of mefloquine. Mefloquine caused a dose-dependent loss of cochlear hair cells at doses exceeding 0.01 mM. Hair cell loss progressed from base to apex and from outer to inner hair cells with increasing dose. Spiral ganglion neurons and auditory nerve fibers were also rapidly destroyed by mefloquine in a dose-dependent manner. To investigate the mechanisms underlying mefloquine-induced cell death, cochlear cultures were stained with TO-Pro-3 to identify morphological changes in the nucleus, and with carboxyfluorescein FAM-labeled caspase inhibitor 8, 9 or 3 to determine caspase-mediated cell death. TO-Pro-3-labeled nuclei in hair cells, spiral ganglion neurons and supporting cells were shrunken or fragmented, morphological features characteristic of cells undergoing apoptosis. Both initiator caspase 8 (membrane damage) and caspase 9 (mitochondrial damage), along with executioner caspase 3, were heavily expressed in cochlear hair cells and spiral ganglions after mefloquine treatment. These three caspases were also expressed in support cells, although labeling was less widespread and less intense. These results indicate that mefloquine damages both the sensory and neural elements in the postnatal rat cochlea by initially activating cell death signaling pathways on the cell membrane and in mitochondria.展开更多
The present study established a chronic experimental autoimmune encephalomyelitis model in C57BL/6 mice induced by myelin oligodendrocyte glycoprotein peptides and complete Freund＇s adjuvant. Onset latency was 12 day...The present study established a chronic experimental autoimmune encephalomyelitis model in C57BL/6 mice induced by myelin oligodendrocyte glycoprotein peptides and complete Freund＇s adjuvant. Onset latency was 12 days, with an incidence rate of 100%. Neuropathological characteristics included perivascular inflammatory cell infiltration, demyelination, neuronal degeneration, and axonal damage within cerebral and myelic white matter. Electron microscopy revealed swollen mitochondria, complete organ disappearance, and fused or broken myelin sheath structure, which were accompanied by myelin sheath reconstruction. Moreover, axonal damage was not consistent with demyelination distribution, and severity of axonal damage did not correlate with demyelination. Results suggested that axonal damage in an experimental autoimmune encephalomyelitis model is not secondary to inflammatory demyelination.展开更多
The subgenual cingulate cortex has been found to be different in structure and function in mood and affective disorders compared to healthy individuals. Imaging studies have shown a decrease in function of the subgenu...The subgenual cingulate cortex has been found to be different in structure and function in mood and affective disorders compared to healthy individuals. Imaging studies have shown a decrease in function of the subgenual region in bipolar disorder and depression, with overall glial number shown to be decreased in these disorders. Decreases in subgenual grey matter in SZ have been observed also. In this neuropathological study upon formalin-fixed coronal brain sections we describe the morphological finding of de- creased frequency of subgenual cingulate crown bifurcation (p = 0.02) as compared to control, bipolar and depression cases. This suggests that the cingulate cortex in schizophrenia may be morphologically distinct in utero formation, potentially enabling an early identification of high-risk individuals.展开更多
Neglected tropical diseases are a group of tropical diseases endemic in poor countries even though medical treatment and cures are available. They are considered a global health problem due to the severity of the phys...Neglected tropical diseases are a group of tropical diseases endemic in poor countries even though medical treatment and cures are available. They are considered a global health problem due to the severity of the physiological changes they induce in their hosts. Malaria is a disease caused by Plasmodium sp. that in its cerebral form may lead to acute or long-term neurological deficits, even with effective antimalarial therapy, causing vascular obstruction, reduced cerebral blood flow and many other changes. However, Plasmodium falciparum infection can also develop into a cerebral malaria(CM) disease that can produce neurological damage. This review will discuss the mechanisms involved in the neuropathology caused by CM, focusing on alterations in cognitive, behavior and neurological functions in human and experimental models.展开更多
We explore the hypothesis that a potential explanation for the initiation of motor neuron disease is an unappreciated vulnerability in central nervous system defense,the direct delivery of neurotoxins into motor neuro...We explore the hypothesis that a potential explanation for the initiation of motor neuron disease is an unappreciated vulnerability in central nervous system defense,the direct delivery of neurotoxins into motor neurons via peripheral nerve retrograde transport.This further suggests a mechanism for focal initiation of neuro-degenerative diseases in general,with subsequent spread by network degeneration as suggested by the Frost-Diamond hypothesis.We propose this vulnerability may be a byproduct of vertebrate evolution in a benign aquatic environment,where external surfaces were not exposed to concentrated neurotoxins.展开更多
Gut dysbiosis,a well-known risk factor to triggers the progression of Alzheimer's disease(AD),is strongly associated with metabolic disturbance.Trimethylamine N-oxide(TMAO),produced in the dietary choline metaboli...Gut dysbiosis,a well-known risk factor to triggers the progression of Alzheimer's disease(AD),is strongly associated with metabolic disturbance.Trimethylamine N-oxide(TMAO),produced in the dietary choline metabolism,has been found to accelerate neurodegeneration in AD pathology.In this study,the cognitive function and gut microbiota of TgCRND8(Tg)mice of different ages were evaluated by Morris water maze task(MWMT)and 16S rRNA sequencing,respectively.Young pseudo germ-free(PGF)Tg mice that received faecal microbiota transplants from aged Tg mice and wild-type(WT)mice were selected to determine the role of the gut microbiota in the process of neuropathology.Excessive choline treatment for Tg mice was used to investigate the role of abnormal choline metabolism on the cognitive functions.Our results showed that gut dysbiosis,neuroinflammation response,Ab deposition,tau hyperphosphorylation,TMAO overproduction and cyclin-dependent kinase 5(CDK5)/transcription 3(STAT3)activation occurred in Tg mice age-dependently.Disordered microbiota of aged Tg mice accelerated AD pathology in young Tg mice,with the activation of CDK5/STAT3 signaling in the brains.On the contrary,faecal microbiota transplantation from WT mice alleviated the cognitive deficits,attenuated neuroinflammation,Ab deposition,tau hyperphosphorylation,TMAO overproduction and suppressed CDK5/STAT3 pathway activation in Tg mice.Moreover,excessive choline treatment was also shown to aggravate the cognitive deficits,Ab deposition,neuroinflammation and CDK5/STAT3 pathway activation.These findings provide a novel insight into the interaction between gut dysbiosis and AD progression,clarifying the important roles of gut microbiota-derived substances such as TMAO in AD neuropathology.展开更多
We used the allele-specific PCR-double digestion method on peripheral myelin protein 22 （PMP22） to determine duplication and deletion mutations in the proband and family members of one family with Charcot-Marie-Toot...We used the allele-specific PCR-double digestion method on peripheral myelin protein 22 （PMP22） to determine duplication and deletion mutations in the proband and family members of one family with Charcot-Marie-Tooth disease type 1 and one family with hereditary neuropathy with liability to pressure palsies. The proband and one subclinical family member from the Charcot-Marie-Tooth disease type 1 family had a PMP22 gene duplication; one patient from the hereditary neuropathy with liability to pressure palsies family had a PMP22 gene deletion. Electron microscopic analysis of ultrathin sections of the superficial peroneal nerve from the two probands demonstrated demyelination and myelin sheath hyperplasia, as well as an ＇onion-like＇ structure in the Charcot-Marie-Tooth disease type 1A patient. We observed an irregular thickened myelin sheath and ＇mouse-nibbled＇-Iike changes in the patient with hereditary neuropathy with liability to pressure palsies. In the Charcot-Marie-Tooth disease type 1A patient, nerve electrophysiological examination revealed moderate-to-severe reductions in the motor and sensory conduction velocities of the bilateral median nerve, ulnar nerve, tibial nerve, and sural nerve. Moreover, the compound muscle action potential amplitude was decreased. In the patient with hereditary neuropathy with liability to pressure palsies, the nerve conduction velocity of the bilateral tibial nerve and sural nerve was moderately reduced, and the nerve conduction velocity of the median nerve and ulnar nerve of both upper extremities was slightly reduced.展开更多
基金supported by the National Natural Science Foundation of China, No. 81771140 (to YDZ)the Natural Science Foundation of Jiangsu Province of China, No. BK20201117 (to YDZ)Jiangsu “Six One Project” for Distinguished Medical Scholars of China, No. LGY2020013 (to TJ)
文摘Lamotrigine(LTG)is a widely used drug for the treatment of epilepsy.Emerging clinical evidence suggests that LTG may improve cognitive function in patients with Alzheimer’s disease.However,the underlying molecular mechanisms remain unclear.In this study,amyloid precursor protein/presenilin 1(APP/PS1)double transgenic mice were used as a model of Alzheimer’s disease.Five-month-old APP/PS1 mice were intragastrically administered 30 mg/kg LTG or vehicle once per day for 3 successive months.The cognitive functions of animals were assessed using Morris water maze.Hyperphosphorylated tau and markers of synapse and glial cells were detected by western blot assay.The cell damage in the brain was investigated using hematoxylin and eosin staining.The levels of amyloid-βand the concentrations of interleukin-1β,interleukin-6 and tumor necrosis factor-αin the brain were measured using enzyme-linked immunosorbent assay.Differentially expressed genes in the brain after LTG treatment were analyzed by high-throughput RNA sequencing and real-time polymerase chain reaction.We found that LTG substantially improved spatial cognitive deficits of APP/PS1 mice;alleviated damage to synapses and nerve cells in the brain;and reduced amyloid-βlevels,tau protein hyperphosphorylation,and inflammatory responses.High-throughput RNA sequencing revealed that the beneficial effects of LTG on Alzheimer’s disease-related neuropathologies may have been mediated by the regulation of Ptgds,Cd74,Map3k1,Fosb,and Spp1 expression in the brain.These findings revealed potential molecular mechanisms by which LTG treatment improved Alzheimer’s disease.Furthermore,these data indicate that LTG may be a promising therapeutic drug for Alzheimer’s disease.
基金financial support from the Sino-German Centre(GZ919,M-0679)the Sichuan Science and Technology Program(2024JDHJ0043,2025YFHZ0121)the Sichuan Provincial Administration of Traditional Chinese Medicine(2023zd024,2024zd029).
文摘Dénes and his co-workers recently published a paper in Nature Neuroscience,documenting that neurological abnormalities in COVID are based on microglial dysfunction in the brain.1 In case of acute respiratory syndrome of COVID infection,the central nervous system symptomatology significantly contribute to the severity of this disease.The authors used an autopsy platform allowing morphological and biochemical/molecular biological investigations in postmortem mirror blocks prepared from the brain and peripheral organs of 13 COVID and 23 non-COVID-infected patients.
基金supported by grants PID2020-120308RB-I00 and PID2023-147802OB-I00 funded by MICIU/AEI/10.13039/501100011033FEDER,UE,by Aligning Science Across Parkinson’s(ref.ASAP-020505)through the Michael J.Fox Foundation for Parkinson’s Research+1 种基金by CiberNed Intramural Collaborative Projects(ref.PI2020/09)by the Spanish Fundación Mutua Madrile?a de Investigación Médica(to JLL)。
文摘The development of clinical candidates that modify the natural progression of sporadic Parkinson's disease and related synucleinopathies is a praiseworthy endeavor,but extremely challenging.Therapeutic candidates that were successful in preclinical Parkinson's disease animal models have repeatedly failed when tested in clinical trials.While these failures have many possible explanations,it is perhaps time to recognize that the problem lies with the animal models rather than the putative candidate.In other words,the lack of adequate animal models of Parkinson's disease currently represents the main barrier to preclinical identification of potential disease-modifying therapies likely to succeed in clinical trials.However,this barrier may be overcome by the recent introduction of novel generations of viral vectors coding for different forms of alpha-synuclein species and related genes.Although still facing several limitations,these models have managed to mimic the known neuropathological hallmarks of Parkinson's disease with unprecedented accuracy,delineating a more optimistic scenario for the near future.
基金supported by grants from STI2030-Major Projects,No.2021ZD0204000(to YS)Key Strategic Science and Technology Cooperation Project of the Ministry of Science and Technology of China,No.SQ2023YFE0201430(to YS)+1 种基金the National Natural Science Foundation of China,Nos.31820103005(to YS),32200620(to LW)the Natural Science Foundation of Zhejiang Province of China,No.LZ24C090003(to YS)。
文摘The cerebellum is receiving increasing attention for its cognitive,emotional,and social functions,as well as its unique metabolic profiles.Cerebellar microglia exhibit specialized and highly immunogenic phenotypes under both physiological and pathological conditions.These immune cells communicate with intrinsic and systemic factors and contribute to the structural and functional compartmentalization of the cerebellum.In this review,we discuss the roles of microglia in the cerebellar microenvironment,neuroinflammation,cerebellar adaptation,and neuronal activity,the associated molecular and cellular mechanisms,and potential therapeutic strategies targeting cerebellar microglia in the context of neuroinflammation.Future directions and unresolved questions in this field are further highlighted,particularly regarding therapeutic interventions targeting cerebellar microglia,functional mechanisms and activities of microglia in the cerebellar circuitry,neuronal connectivity,and neurofunctional outcomes of their activity.Cerebellar morphology and neuronal performance are influenced by both intrinsic and systemic factors that are actively monitored by microglia in both healthy and diseased states.Under pathological conditions,local subsets of microglia exhibit diverse responses to the altered microenvironment that contribute to the structural and functional compartmentalization of the cerebellum.Microglia in the cerebellum undergo early maturation during the embryonic stage and display specialized,highly immunogenic phenotypes.In summary,cerebellar microglia have the capacity to serve as regulatory tools that influence outcomes across a wide range of neurological and systemic conditions,including neurodevelopmental,neurodegenerative,metabolic,and stress-related disorders.
基金supported by the National Natural Science Foundation of China(82171908 and 82102015)the General Project of the Nanjing Medical Science and Technology Development Program(YKK21075)the Guangdong Basic and Applied Basic Research Foundation(No.2023A1515140030).
文摘Background:Platinum can cause chemotherapy-related cognitive impairment.Low-intensity focused ultrasound(LIFUS)is a promising noninvasive physical stimulation method with a unique advantage in neurological rehabilitation.We aimed to investigate whether LIFUS can alleviate cisplatin-induced cognitive impairment in rats and explore the related neuropatho-logical mechanisms.Methods:After confirming the target position for LIFUS treatment in 18 rats,64 rats were randomly divided into four groups:control,model,sham,and LIFUS groups.Before and after LIFUS treatment,detailed biological behavioral assessments and magnetic resonance imaging were performed.Finally,the rats were euthanized,and relevant histopathological and molecular biological experiments were conducted and analyzed.Results:In the Morris water maze,the model group showed fewer platform crossings(1.250.93 vs.5.691.58),a longer escape latency(41.6536.55 s vs.6.382.11 s),and a lower novel object recognition index(29.7711.83 vs.83.695.67)than the control group.LIFUS treatment improved these metrics,with more platform crossings(3.130.34),a higher recognition index(65.588.71),and a shorter escape latency(6.452.27 s).Longitudinal analysis of the LIFUS group further confirmed these improvements.Neuroimaging revealed significant differences in diffusion tensor imaging metrics of specific brain regions pre-and post-LIFUS.Moreover,neuropathology showed higher dendritic spine density,less myelin loss,fewer apoptotic cells,more synapses,and less mitochondrial autophagy after LIFUS treatment.The neuroimaging indicators were correlated with behavioral improvements,highlighting the potential of LIFUS for alleviating cognitive impairment(as demonstrated through imaging and analysis).Our investigation of the molecular biological mechanisms revealed distinct protein expression patterns in the hippocampus and its subregions.In the model group,glial fibrillary acidic protein(GFAP)and ionized calcium-binding adaptor molecule 1(IBA1)expression levels were elevated across the hippocampus,whereas neuronal nuclei(NeuN)expression was reduced.Subregional analysis revealed higher GFAP and IBA1 and lower NeuN,especially in the dentate gyrus subregion.Moreover,positive cell areas were larger in the cornu ammonis(CA)1,CA2,CA3,and dentate gyrus regions.In the CA2 and CA3,significant differences among the groups were observed in GFAP-positive cell counts and areas,and there were variations in NeuN expression.Conclusions:Our results suggest that LIFUS can reverse cisplatin-induced cognitive impairments.The neuroimaging findings were consistent with the behavioral and histological results and suggest a neuropathological basis that supports further research into the clinical applications of LIFUS.Furthermore,LIFUS appeared to enhance the plasticity of neuronal synapses in the rat hippocampus and reduce hippocampal inflammation.These findings highlight the clinical potential of LIFUS as an effective,noninvasive therapeutic strategy and monitoring tool for chemotherapy-induced cognitive deficits.
基金supported by grants from the Health Ministry,PNSD(2018-I003)Institute Carlos III and FEDER funds(RTA-Network,RD16 0017 0004)+1 种基金Spanish Ministry of Science and Innovation(SAF2015-69187R)FEDER Funds,Generalitat Valenciana
文摘In recent years,a type of extracellular vesicles named exosomes has emerged that play an important role in intercellular communication under physiological and pathological conditions.These nanovesicles (30–150 nm) contain proteins,RNAs and lipids,and their internalization by bystander cells could alter their normal functions.This review focuses on recent knowledge about exosomes as messengers of neuron-glia communication and their participation in the physiological and pathological functions in the central nervous system.Special emphasis is placed on the role of exosomes under toxic or pathological stimuli within the brain,in which the glial exosomes containing inflammatory molecules are able to communicate with neurons and contribute to the pathogenesis of neuroinflammation and neurodegenerative disorders.Given the small size and characteristics of exosomes,they can cross the blood-brain barrier and be used as biomarkers and diagnosis for brain disorders and neuropathologies.Finally,although the application potential of exosome is still limited,current studies indicate that exosomes represent a promising strategy to gain pathogenic information to identify therapeutically targets and biomarkers for neurological disorders and neuroinflammation.
文摘The current study sought to observe the effects of lead on histological structure and antioxidant capacity in 30-day-old mice.Spectrophotometry was used to detect the activities of superoxide dismutase,catalase,alkaline phosphatase,acid phosphatase and the malondialdehyde content.The results revealed that Purkinje cells in the lead-exposed group exhibited obvious pyknosis,atrophy and a decrease in overall number.Granular cells exhibited a disorderly arrangement,and were reduced in number.Administration of lead decreased the activities of superoxide dismutase,catalase,alkaline phosphatase and acid phosphatase,while malondialdehyde content increased.Two-way analysis of variance indicated that dose contributed more to lead-induced cerebellum damage than treatment time.The present study demonstrated that lead exerted strong effects on histological structure and inhibited antioxidant capacity of the cerebellum in 30-day-old mice.
文摘The most common age-related neurodegenerative disease is Alzheimer's disease(AD) characterized by aggregated amyloid-β(Aβ) peptides in extracellular plaques and aggregated hyperphosphorylated tau protein in intraneuronal neurofibrillary tangles,together with loss of cholinergic neurons,synaptic alterations,and chronic inflammation within the brain.These lead to progressive impairment of cognitive function.There is evidence of innate immune activation in AD with microgliosis.Classically-activated microglia(M1 state) secrete inflammatory and neurotoxic mediators,and peripheral immune cells are recruited to inflammation sites in the brain.The few drugs approved by the US FDA for the treatment of AD improve symptoms but do not change the course of disease progression and may cause some undesirable effects.Translation of active and passive immunotherapy targeting Aβ in AD animal model trials had limited success in clinical trials.Treatment with immunomodulatory/anti-inflammatory agents early in the disease process,while not preventive,is able to inhibit the inflammatory consequences of both Aβ and tau aggregation.The studies described in this review have identified several agents with immunomodulatory properties that alleviated AD pathology and cognitive impairment in animal models of AD.The majority of the animal studies reviewed had used transgenic models of early-onset AD.More effort needs to be given to creat models of late-onset AD.The effects of a combinational therapy involving two or more of the tested pharmaceutical agents,or one of these agents given in conjunction with one of the cell-based therapies,in an aged animal model of AD would warrant investigation.
基金This work was supported by Chinese National Natural Science Foundation Grants 39928018,30070038 and 30130070, National High-tech Development Project (863 Project) 2001AA215391EU Project QLRT 2000 01441.
文摘Objective To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.e.), intraperitoneal (i.p.), intragastrical (i.g.), intracardiac and intramuscular (i.m.) approaches. Methods Hamsters were infected with crude- or fine-prepared brain extracts. The neuropathological changes, PrPSc deposits, and patterns of PK-resistant PrP were analyzed by HE stain, immunohistochemistry (IHC) assay and Western blot. Reactive gliosis and neuron loss were evaluated by glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE) specific IHC. Results The animals inoculated in i.m. and Lp. ways with crude PrPSc extracts showed clinical signs at the average incubation of 69.212.8 and 65.5±3.9 days. Inoculation in i.c. and intracardiac ways with fine PrPSc extracts (0.00035 g) caused similar, but relative long incubation of around 90 days. Only one out of eight hamsters challenged in i.g way with low dosage (0.01 g) became ill after a much longer incubation (185 d), while all animals (4/4) with high dosage (0.04 g) developed clinical signs 105 days postinfection. The most remarkable spongiform degeneration and PrPSc deposits were found in brain stem among the five challenge groups generally. The number of GFAP-positive astrocytes increased distinctly in brain stems in all infection groups, while the number of NSE-positive cells decreased significantly in cerebrum, except i.c. group. The patterns of PK-resistant PrP in brains were basically identical among the five infection routes. Conclusion Typical TSE could be induced in hamsters by inoculating strain 263K in the five infection ways. The incubation periods in bioassays depend on infective dosage, administrating pathway and preparation of PrPSc. The neuropathological changes and PrPSc deposits seem to be related with regions and inoculating pathways.
基金supported by the Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health(NIH,P30HD071593)
文摘Attention-deficit/hyperactivity disorder （ADHD） is a neurodevelopmental disorder with a long-term impact on functioning, productivity and quality of life of patients. This impact is largely due to the symptoms of inattentiveness. However, despite its impairing role in the lives of ADHD patients, inattentiveness has been studied relatively less frequently than have symptoms of impulsivity/hyperactivity and problems with executive function. This review therefore seeks to integrate the neuropsychological theories and current findings in the research fields of neuropsychology, neurophysiology, and neuroimaging, in an attempt to gain a more complete understanding of the role that inattentiveness plays in ADHD, as well as to suggest directions for future studies. The need for a more comprehensive understanding of inattentiveness and ADHD, which integrates findings from each of the three disciplines mentioned above, is emphasized.
基金supported by the National Natural Science Foundation of China,No.81141013a grant for Talents in Beijing,No.2011D003034000019
文摘3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer＇s disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain function of Alzheimer＇s disease remains unclear. In this study, 7.0T magnetic resonance spectroscopy showed that in the hippocampus of Alzheimer＇s disease rats, the N-acetylaspartate wave crest was reduced, and the creatine and choline wave crest was elevated. This finding was further supported by hematoxylin-eosin staining, which showed a loss of hippocampal neurons and more glial cells. Moreover, electron microscopy showed neuronal shrinkage and mitochondrial rupture, and scanning electron microscopy revealed small size hippocampal synaptic vesicles, incomplete synaptic structure, and reduced number. Overall, the results revealed that 7.0T high-field nuclear magnetic resonance spectroscopy detected the lesions and functional changes in hippocampal neurons of Alzheimer＇s disease rats in vivo, allowing the possibility for assessing the success rate and grading of the amyloid beta （1-40） animal model of Alzheimer＇s disease.
文摘A physiological state of＂normoxia＂obtains when tissue oxygen tension（pO_2）is sufficient to drive mitochondrial respiration throughout a volume of cells.Between 30-40%of the available oxygen is normally extracted from hemoglobin as it passes through neural tissue.
文摘Mefloquine is a widely used anti-malarial drug. Some clinical reports suggest that mefloquine may be ototoxic and neurotoxic, but there is little scientific evidence from which to draw any firm conclusion. To evaluate the ototoxic and neurotoxic potential of mefloquine, we treated cochlear organotypic cultures and spiral ganglion cultures with various concentrations of mefloquine. Mefloquine caused a dose-dependent loss of cochlear hair cells at doses exceeding 0.01 mM. Hair cell loss progressed from base to apex and from outer to inner hair cells with increasing dose. Spiral ganglion neurons and auditory nerve fibers were also rapidly destroyed by mefloquine in a dose-dependent manner. To investigate the mechanisms underlying mefloquine-induced cell death, cochlear cultures were stained with TO-Pro-3 to identify morphological changes in the nucleus, and with carboxyfluorescein FAM-labeled caspase inhibitor 8, 9 or 3 to determine caspase-mediated cell death. TO-Pro-3-labeled nuclei in hair cells, spiral ganglion neurons and supporting cells were shrunken or fragmented, morphological features characteristic of cells undergoing apoptosis. Both initiator caspase 8 (membrane damage) and caspase 9 (mitochondrial damage), along with executioner caspase 3, were heavily expressed in cochlear hair cells and spiral ganglions after mefloquine treatment. These three caspases were also expressed in support cells, although labeling was less widespread and less intense. These results indicate that mefloquine damages both the sensory and neural elements in the postnatal rat cochlea by initially activating cell death signaling pathways on the cell membrane and in mitochondria.
基金the Natural Science Foundation of Ministry of Science and Technology of China,No.30230140a grant from Merck Serono (China)
文摘The present study established a chronic experimental autoimmune encephalomyelitis model in C57BL/6 mice induced by myelin oligodendrocyte glycoprotein peptides and complete Freund＇s adjuvant. Onset latency was 12 days, with an incidence rate of 100%. Neuropathological characteristics included perivascular inflammatory cell infiltration, demyelination, neuronal degeneration, and axonal damage within cerebral and myelic white matter. Electron microscopy revealed swollen mitochondria, complete organ disappearance, and fused or broken myelin sheath structure, which were accompanied by myelin sheath reconstruction. Moreover, axonal damage was not consistent with demyelination distribution, and severity of axonal damage did not correlate with demyelination. Results suggested that axonal damage in an experimental autoimmune encephalomyelitis model is not secondary to inflammatory demyelination.
文摘The subgenual cingulate cortex has been found to be different in structure and function in mood and affective disorders compared to healthy individuals. Imaging studies have shown a decrease in function of the subgenual region in bipolar disorder and depression, with overall glial number shown to be decreased in these disorders. Decreases in subgenual grey matter in SZ have been observed also. In this neuropathological study upon formalin-fixed coronal brain sections we describe the morphological finding of de- creased frequency of subgenual cingulate crown bifurcation (p = 0.02) as compared to control, bipolar and depression cases. This suggests that the cingulate cortex in schizophrenia may be morphologically distinct in utero formation, potentially enabling an early identification of high-risk individuals.
基金Conselho Nacional de Desenvolvi-mento Científico e Tecnológico (CNPq), FAPESPA, Federal University of Pará and the Federal University of Health Sciences of Porto Alegre
文摘Neglected tropical diseases are a group of tropical diseases endemic in poor countries even though medical treatment and cures are available. They are considered a global health problem due to the severity of the physiological changes they induce in their hosts. Malaria is a disease caused by Plasmodium sp. that in its cerebral form may lead to acute or long-term neurological deficits, even with effective antimalarial therapy, causing vascular obstruction, reduced cerebral blood flow and many other changes. However, Plasmodium falciparum infection can also develop into a cerebral malaria(CM) disease that can produce neurological damage. This review will discuss the mechanisms involved in the neuropathology caused by CM, focusing on alterations in cognitive, behavior and neurological functions in human and experimental models.
基金supported by grants from the New Jersey Commission on Spinal Cord Research (05-304711-015)
文摘We explore the hypothesis that a potential explanation for the initiation of motor neuron disease is an unappreciated vulnerability in central nervous system defense,the direct delivery of neurotoxins into motor neurons via peripheral nerve retrograde transport.This further suggests a mechanism for focal initiation of neuro-degenerative diseases in general,with subsequent spread by network degeneration as suggested by the Frost-Diamond hypothesis.We propose this vulnerability may be a byproduct of vertebrate evolution in a benign aquatic environment,where external surfaces were not exposed to concentrated neurotoxins.
基金This work was partially supported by National Natural Science Foundation of China(Project No.:82104414)Natural Science Foundation of Guangdong Province of China(Project No.:2022A1515011682)a direct grant from The Chinese University of Hong Kong(Project No.:2021.071).
文摘Gut dysbiosis,a well-known risk factor to triggers the progression of Alzheimer's disease(AD),is strongly associated with metabolic disturbance.Trimethylamine N-oxide(TMAO),produced in the dietary choline metabolism,has been found to accelerate neurodegeneration in AD pathology.In this study,the cognitive function and gut microbiota of TgCRND8(Tg)mice of different ages were evaluated by Morris water maze task(MWMT)and 16S rRNA sequencing,respectively.Young pseudo germ-free(PGF)Tg mice that received faecal microbiota transplants from aged Tg mice and wild-type(WT)mice were selected to determine the role of the gut microbiota in the process of neuropathology.Excessive choline treatment for Tg mice was used to investigate the role of abnormal choline metabolism on the cognitive functions.Our results showed that gut dysbiosis,neuroinflammation response,Ab deposition,tau hyperphosphorylation,TMAO overproduction and cyclin-dependent kinase 5(CDK5)/transcription 3(STAT3)activation occurred in Tg mice age-dependently.Disordered microbiota of aged Tg mice accelerated AD pathology in young Tg mice,with the activation of CDK5/STAT3 signaling in the brains.On the contrary,faecal microbiota transplantation from WT mice alleviated the cognitive deficits,attenuated neuroinflammation,Ab deposition,tau hyperphosphorylation,TMAO overproduction and suppressed CDK5/STAT3 pathway activation in Tg mice.Moreover,excessive choline treatment was also shown to aggravate the cognitive deficits,Ab deposition,neuroinflammation and CDK5/STAT3 pathway activation.These findings provide a novel insight into the interaction between gut dysbiosis and AD progression,clarifying the important roles of gut microbiota-derived substances such as TMAO in AD neuropathology.
基金funded by the National Natural Science Foundation of China, grant No. 81071001 and 30600200
文摘We used the allele-specific PCR-double digestion method on peripheral myelin protein 22 （PMP22） to determine duplication and deletion mutations in the proband and family members of one family with Charcot-Marie-Tooth disease type 1 and one family with hereditary neuropathy with liability to pressure palsies. The proband and one subclinical family member from the Charcot-Marie-Tooth disease type 1 family had a PMP22 gene duplication; one patient from the hereditary neuropathy with liability to pressure palsies family had a PMP22 gene deletion. Electron microscopic analysis of ultrathin sections of the superficial peroneal nerve from the two probands demonstrated demyelination and myelin sheath hyperplasia, as well as an ＇onion-like＇ structure in the Charcot-Marie-Tooth disease type 1A patient. We observed an irregular thickened myelin sheath and ＇mouse-nibbled＇-Iike changes in the patient with hereditary neuropathy with liability to pressure palsies. In the Charcot-Marie-Tooth disease type 1A patient, nerve electrophysiological examination revealed moderate-to-severe reductions in the motor and sensory conduction velocities of the bilateral median nerve, ulnar nerve, tibial nerve, and sural nerve. Moreover, the compound muscle action potential amplitude was decreased. In the patient with hereditary neuropathy with liability to pressure palsies, the nerve conduction velocity of the bilateral tibial nerve and sural nerve was moderately reduced, and the nerve conduction velocity of the median nerve and ulnar nerve of both upper extremities was slightly reduced.
