Parkinson’s disease(PD)is a multifaceted disease in which environmental variables combined with genetic predisposition cause dopaminergic(DAergic)neuron loss in the substantia nigra pars compacta.The mutation of leuc...Parkinson’s disease(PD)is a multifaceted disease in which environmental variables combined with genetic predisposition cause dopaminergic(DAergic)neuron loss in the substantia nigra pars compacta.The mutation of leucine-rich repeat kinase 2(Lrrk2)is the most common autosomal dominant mutation in PD,and it has also been reported in sporadic cases.A growing body of research suggests that circadian rhythm disruption,particularly sleep-wake abnormality,is common during the early phase of PD.Our present study aimed to evaluate the impact of sleep deprivation(SD)on motor ability,sleep performance,and PD pathologies in Lrrk2^(G2019S) transgenic mice.After two months of SD,Lrrk2^(G2019S) mice at 12 months of age showed an exacerbated PD-like phenotype with motor deficits,a reduced striatal DA level,degenerated DAergic neurons,and altered sleep structure and biological rhythm accompanied by the decreased protein expression level of circadian locomotor output cycles kaput Lrrk2 gene in the brain.All these changes persisted and were even more evident in 18-month-old mice after 6 months of follow-up.Moreover,a significant increase inα-synuclein aggregation was found in SD-treated transgenic mice at 18 months of age.Taken together,our findings indicate that sleep abnormalities,as a risk factor,may contribute to the pathogenesis and progression of PD.Early detection of sleep disorders and improvement of sleep quality may help to delay disease progression and provide long-term clinical benefits.展开更多
Background Previous studies have shown that astrocytes can transfer healthy mitochondria to dopaminergic(DA)neurons,which may serve as an intrinsic neuroprotective mechanism in Parkinson’s disease(PD).LRRK2 G2019S is...Background Previous studies have shown that astrocytes can transfer healthy mitochondria to dopaminergic(DA)neurons,which may serve as an intrinsic neuroprotective mechanism in Parkinson’s disease(PD).LRRK2 G2019S is the most common pathogenic mutation associated with PD.In this study,we explored whether mitochondrial transfer is influenced by genetic and environmental factors and whether dysfunction in this process is one of the mechanisms of the pathogenic LRRK2 G2019S mutation.Methods DA neurons and astrocytes were differentiated from induced pluripotent stem cells generated from the peripheral blood of a healthy individual and a PD patient carrying the LRRK2 G2019S mutation.A coculture system of astrocytes and DA neurons was established to explore the pathogenic mechanisms of LRRK2 G2019S.Results Exposure to the environmental toxin rotenone impaired mitochondrial transfer from astrocytes to DA neurons.Compared with the co-culture system from the healthy participant,the co-culture system harboring the LRRK2 G2019S mutation experienced more pronounced damage.Specifically,STX17 was colocalized with the mitochondrial outer membrane marker TOM20,and its knockdown caused damage to mitochondrial transfer.Drp1 interacted with STX17.LRRK2 G2019S-mutant astrocytes exhibited markedly increased phosphorylation of Drp1 at Ser616 upon rotenone exposure.Moreover,the degree of colocalization of STX17 with TOM20 decreased.The Drp1 phosphorylation inhibitor DUSP6 restored the colocalization of STX17 and TOM20,as well as the mitochondrial transfer efficiency and neuronal survival.Conclusions The impairment of mitochondrial transfer is a potential pathogenic mechanism associated with LRRK2 G2019S mutation.The molecular mechanisms of mitochondrial transfer were observed to occur through a Drp1-STX17-dependent pathway.Notably,inhibitors for Drp1 Ser616 phosphorylation may offer neuroprotection through mitigating mitochondrial transfer impairments.This study provides novel insights into the pathogenesis of PD and the development of new therapeutic targets.展开更多
Background:Leucine-rich repeat kinase 2(LRRK2)mutations represent the most common genetic cause of sporadic and familial Parkinson’s disease(PD).Especially,LRRK2 G2019S missense mutation has been identified as the mo...Background:Leucine-rich repeat kinase 2(LRRK2)mutations represent the most common genetic cause of sporadic and familial Parkinson’s disease(PD).Especially,LRRK2 G2019S missense mutation has been identified as the most prevalent genetic cause in the late-onset PD.Advanced glycation end products(AGEs)are produced in high amounts in diabetes and diverse aging-related disorders,such as cardiovascular disease,renal disease,and neurological disease.AGEs trigger intracellular signaling pathway associated with oxidative stress and inflammation as well as cell death.RAGE,receptor of AGEs,is activated by interaction with AGEs and mediates AGE-induced cytotoxicity.Whether AGE and RAGE are involved in the pathogenesis of mutant LRRK2 is unknown.Methods:Using cell lines transfected with mutant LRRK2 as well as primary neuronal cultures derived from LRRK2 wild-type(WT)and G2019S transgenic mice,we compared the impact of AGE treatment on the survival of control and mutant cells by immunostaining.We also examined the levels of RAGE proteins in the brains of transgenic mice and PD patients by western blots.Results:We show that LRRK2 G2019S mutant-expressing neurons were more sensitive to AGE-induced cell death compared to controls.Furthermore,we found that the levels of RAGE proteins were upregulated in LRRK2 G2019S mutant cells.Conclusions:These data suggest that enhanced AGE-RAGE interaction contributes to LRRK2 G2019S mutation-mediated progressive neuronal loss in PD.展开更多
Background Mutations in leucine-rich repeat kinase 2(LRRK2)are the most common cause of familial Parkinson’s disease(PD).These mutations elevate the LRRK2 kinase activity,making LRRK2 kinase inhibitors an attractive ...Background Mutations in leucine-rich repeat kinase 2(LRRK2)are the most common cause of familial Parkinson’s disease(PD).These mutations elevate the LRRK2 kinase activity,making LRRK2 kinase inhibitors an attractive therapeutic.LRRK2 kinase activity has been consistently linked to specific cell signaling pathways,mostly related to organelle trafficking and homeostasis,but its relationship to PD pathogenesis has been more difficult to define.LRRK2-PD patients consistently present with loss of dopaminergic neurons in the substantia nigra but show variable development of Lewy body or tau tangle pathology.Animal models carrying LRRK2 mutations do not develop robust PD-related phenotypes spontaneously,hampering the assessment of the efficacy of LRRK2 inhibitors against disease processes.We hypothesized that mutations in LRRK2 may not be directly related to a single disease pathway,but instead may elevate the susceptibility to multiple disease processes,depending on the disease trigger.To test this hypothesis,we have previously evaluated progression ofα-synuclein and tau pathologies following injection of proteopathic seeds.We demonstrated that transgenic mice overexpressing mutant LRRK2 show alterations in the brain-wide progression of pathology,especially at older ages.Methods Here,we assess tau pathology progression in relation to long-term LRRK2 kinase inhibition.Wild-type or LRRK2^(G2019S) knock-in mice were injected with tau fibrils and treated with control diet or diet containing LRRK2 kinase inhibitor MLi-2 targeting the IC50 or IC90 of LRRK2 for 3-6 months.Mice were evaluated for tau pathology by brain-wide quantitative pathology in 844 brain regions and subsequent linear diffusion modeling of progression.Results Consistent with our previous work,we found systemic alterations in the progression of tau pathology in LRRK2^(G2019S) mice,which were most pronounced at 6 months.Importantly,LRRK2 kinase inhibition reversed these effects in LRRK2^(G2019S) mice,but had minimal effect in wild-type mice,suggesting that LRRK2 kinase inhibition is likely to reverse specific disease processes in G2019S mutation carriers.Additional work may be necessary to determine the potential effect in non-carriers.Conclusions This work supports a protective role of LRRK2 kinase inhibition in G2019S carriers and provides a rational workflow for systematic evaluation of brain-wide phenotypes in therapeutic development.展开更多
基金We thank Liaoning Provincial Center for Clinical Research on Neurological Diseases,the First Affiliated Hospital,and Dalian Medical University for the research infrastructure and support.This work was supported by the National Natural Science Foundation of China(81771521).
文摘Parkinson’s disease(PD)is a multifaceted disease in which environmental variables combined with genetic predisposition cause dopaminergic(DAergic)neuron loss in the substantia nigra pars compacta.The mutation of leucine-rich repeat kinase 2(Lrrk2)is the most common autosomal dominant mutation in PD,and it has also been reported in sporadic cases.A growing body of research suggests that circadian rhythm disruption,particularly sleep-wake abnormality,is common during the early phase of PD.Our present study aimed to evaluate the impact of sleep deprivation(SD)on motor ability,sleep performance,and PD pathologies in Lrrk2^(G2019S) transgenic mice.After two months of SD,Lrrk2^(G2019S) mice at 12 months of age showed an exacerbated PD-like phenotype with motor deficits,a reduced striatal DA level,degenerated DAergic neurons,and altered sleep structure and biological rhythm accompanied by the decreased protein expression level of circadian locomotor output cycles kaput Lrrk2 gene in the brain.All these changes persisted and were even more evident in 18-month-old mice after 6 months of follow-up.Moreover,a significant increase inα-synuclein aggregation was found in SD-treated transgenic mice at 18 months of age.Taken together,our findings indicate that sleep abnormalities,as a risk factor,may contribute to the pathogenesis and progression of PD.Early detection of sleep disorders and improvement of sleep quality may help to delay disease progression and provide long-term clinical benefits.
基金supported by the National Natural Science Foundation of China(82101333 to X.-Y.C.)The Gusu Health Talents Project(GSWS2022035 to X.-Y.C.)+3 种基金Jiangsu Provincial Medical Key Discipline(ZDXK202217 to C.-F.L.)Suzhou Key Laboratory of Sleep Disorders Diagnosis and Treatment Technology(SZS2023015 to C.-F.L.)Xiongan New Area Science and Technology Innovation Project(2023XAGG0073 to C.-F.L.)Natural Science Foundation of Jiangsu Province(BK20240356 to M.C.).
文摘Background Previous studies have shown that astrocytes can transfer healthy mitochondria to dopaminergic(DA)neurons,which may serve as an intrinsic neuroprotective mechanism in Parkinson’s disease(PD).LRRK2 G2019S is the most common pathogenic mutation associated with PD.In this study,we explored whether mitochondrial transfer is influenced by genetic and environmental factors and whether dysfunction in this process is one of the mechanisms of the pathogenic LRRK2 G2019S mutation.Methods DA neurons and astrocytes were differentiated from induced pluripotent stem cells generated from the peripheral blood of a healthy individual and a PD patient carrying the LRRK2 G2019S mutation.A coculture system of astrocytes and DA neurons was established to explore the pathogenic mechanisms of LRRK2 G2019S.Results Exposure to the environmental toxin rotenone impaired mitochondrial transfer from astrocytes to DA neurons.Compared with the co-culture system from the healthy participant,the co-culture system harboring the LRRK2 G2019S mutation experienced more pronounced damage.Specifically,STX17 was colocalized with the mitochondrial outer membrane marker TOM20,and its knockdown caused damage to mitochondrial transfer.Drp1 interacted with STX17.LRRK2 G2019S-mutant astrocytes exhibited markedly increased phosphorylation of Drp1 at Ser616 upon rotenone exposure.Moreover,the degree of colocalization of STX17 with TOM20 decreased.The Drp1 phosphorylation inhibitor DUSP6 restored the colocalization of STX17 and TOM20,as well as the mitochondrial transfer efficiency and neuronal survival.Conclusions The impairment of mitochondrial transfer is a potential pathogenic mechanism associated with LRRK2 G2019S mutation.The molecular mechanisms of mitochondrial transfer were observed to occur through a Drp1-STX17-dependent pathway.Notably,inhibitors for Drp1 Ser616 phosphorylation may offer neuroprotection through mitigating mitochondrial transfer impairments.This study provides novel insights into the pathogenesis of PD and the development of new therapeutic targets.
基金This work was supported by the intramural research programs of National Institute on Aging,National Institutes of Health(HC:AG000944).
文摘Background:Leucine-rich repeat kinase 2(LRRK2)mutations represent the most common genetic cause of sporadic and familial Parkinson’s disease(PD).Especially,LRRK2 G2019S missense mutation has been identified as the most prevalent genetic cause in the late-onset PD.Advanced glycation end products(AGEs)are produced in high amounts in diabetes and diverse aging-related disorders,such as cardiovascular disease,renal disease,and neurological disease.AGEs trigger intracellular signaling pathway associated with oxidative stress and inflammation as well as cell death.RAGE,receptor of AGEs,is activated by interaction with AGEs and mediates AGE-induced cytotoxicity.Whether AGE and RAGE are involved in the pathogenesis of mutant LRRK2 is unknown.Methods:Using cell lines transfected with mutant LRRK2 as well as primary neuronal cultures derived from LRRK2 wild-type(WT)and G2019S transgenic mice,we compared the impact of AGE treatment on the survival of control and mutant cells by immunostaining.We also examined the levels of RAGE proteins in the brains of transgenic mice and PD patients by western blots.Results:We show that LRRK2 G2019S mutant-expressing neurons were more sensitive to AGE-induced cell death compared to controls.Furthermore,we found that the levels of RAGE proteins were upregulated in LRRK2 G2019S mutant cells.Conclusions:These data suggest that enhanced AGE-RAGE interaction contributes to LRRK2 G2019S mutation-mediated progressive neuronal loss in PD.
基金supported by the Michael J.Fox Foundation for Parkinson’s Research(MJFF)grant 16879(M.X.H)and Aligning Science Across Parkinson’s ASAP-020616 through MJFFNIH grants:R01-AG077573(D.S.B,M.X.H.)NSF grants PHY-1554488(D.S.B)and BCS-1631550(D.S.B).D.S.B.also acknowledges support from the John D.and Catherine T.MacArthur Foundation,the ISI Foundation,the Alfred P.Sloan Foundation,and the Paul G.Allen Foundation.
文摘Background Mutations in leucine-rich repeat kinase 2(LRRK2)are the most common cause of familial Parkinson’s disease(PD).These mutations elevate the LRRK2 kinase activity,making LRRK2 kinase inhibitors an attractive therapeutic.LRRK2 kinase activity has been consistently linked to specific cell signaling pathways,mostly related to organelle trafficking and homeostasis,but its relationship to PD pathogenesis has been more difficult to define.LRRK2-PD patients consistently present with loss of dopaminergic neurons in the substantia nigra but show variable development of Lewy body or tau tangle pathology.Animal models carrying LRRK2 mutations do not develop robust PD-related phenotypes spontaneously,hampering the assessment of the efficacy of LRRK2 inhibitors against disease processes.We hypothesized that mutations in LRRK2 may not be directly related to a single disease pathway,but instead may elevate the susceptibility to multiple disease processes,depending on the disease trigger.To test this hypothesis,we have previously evaluated progression ofα-synuclein and tau pathologies following injection of proteopathic seeds.We demonstrated that transgenic mice overexpressing mutant LRRK2 show alterations in the brain-wide progression of pathology,especially at older ages.Methods Here,we assess tau pathology progression in relation to long-term LRRK2 kinase inhibition.Wild-type or LRRK2^(G2019S) knock-in mice were injected with tau fibrils and treated with control diet or diet containing LRRK2 kinase inhibitor MLi-2 targeting the IC50 or IC90 of LRRK2 for 3-6 months.Mice were evaluated for tau pathology by brain-wide quantitative pathology in 844 brain regions and subsequent linear diffusion modeling of progression.Results Consistent with our previous work,we found systemic alterations in the progression of tau pathology in LRRK2^(G2019S) mice,which were most pronounced at 6 months.Importantly,LRRK2 kinase inhibition reversed these effects in LRRK2^(G2019S) mice,but had minimal effect in wild-type mice,suggesting that LRRK2 kinase inhibition is likely to reverse specific disease processes in G2019S mutation carriers.Additional work may be necessary to determine the potential effect in non-carriers.Conclusions This work supports a protective role of LRRK2 kinase inhibition in G2019S carriers and provides a rational workflow for systematic evaluation of brain-wide phenotypes in therapeutic development.
