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Progressive parkinsonism in mice with respiratory-chain-deficient dopamine neurons
Open accessAbstract
Mitochondrial dysfunction is implicated in the pathophysiology of Parkinson′s disease (PD), a common age-associated neurodegenerative disease characterized by intraneuronal inclusions (Lewy bodies) and progressive degeneration of the nigrostriatal dopamine (DA) system. It has recently been demonstrated that midbrain DA neurons of PD patients and elderly humans contain high levels of somatic mtDNA mutations, which may impair respiratory chain function. However, clinical studies have not established whether the respiratory chain deficiency is a primary abnormality leading to inclusion formation and DA neuron death, or whether generalized metabolic abnormalities within the degenerating DA neurons cause secondary damage to mitochondria. We have used a reverse genetic approach to investigate this question and created conditional knockout mice (termed MitoPark mice), with disruption of the gene for mitochondrial transcription factor A ( Tfam ) in DA neurons. The knockout mice have reduced mtDNA expression and respiratory chain deficiency in midbrain DA neurons, which, in turn, leads to a parkinsonism phenotype with adult onset of slowly progressive impairment of motor function accompanied by formation of intraneuronal inclusions and dopamine nerve cell death. Confocal and electron microscopy show that the inclusions contain both mitochondrial protein and membrane components. These experiments demonstrate that respiratory chain dysfunction in DA neurons may be of pathophysiological importance in PD.
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TL;DR
MitoPark mice with conditional Tfam disruption in midbrain dopamine neurons develop respiratory chain deficiency, adult-onset progressive parkinsonism, intraneuronal inclusions, and dopamine neuron death. The findings provide genetic evidence that respiratory chain dysfunction in dopamine neurons may be pathophysiologically important in Parkinson’s disease.
Key findings
- MitoPark mice had reduced mtDNA expression in midbrain DA neurons at 6 weeks and marked reduction of COX enzyme activity at 20 weeks.
- Motor impairment began at ≈14–15 weeks, progressed to tremor, twitching, and apparent limb rigidity at ≈20 weeks, and mice were killed at ≈45 weeks; L-DOPA improved motor performance, with older mice showing abrupt termination resembling “wearing off.”
- DA innervation loss first appeared in dorsolateral striatum at 12 weeks; TH+ midbrain neuron loss was earlier and more marked in SN than VTA, and 20-week-old MitoPark mice had DA loss plus increased HVA/DA and DOPAC/DA ratios.
- Most midbrain DA neurons contained small cytoplasmic inclusions at 6 weeks before DA cell loss; inclusions contained mitochondrial protein and membrane components by confocal and electron microscopy, but did not contain α-synuclein and persisted in α-synuclein knockout MitoPark mice.
Methods
- Reverse genetic conditional knockout: DAT-cre mice were crossed with TfamloxP/TfamloxP mice to disrupt Tfam in midbrain DA neurons; cre expression was validated by in situ hybridization and reporter mice.
- Behavioral testing used automated activity cages for locomotion and rearing, with L-DOPA plus benserazide or PBS injections; histology, immunohistochemistry, in situ hybridization, electron microscopy, confocal microscopy, and HPLC catecholamine measurements were used.
- Sample sizes included 7 MitoPark/control pairs for in situ hybridization and enzyme histochemistry, 20 pairs for immunohistochemistry, 18 mice (9 littermate pairs) for TH cell counts, and 9 animals for aggregate counts and size measurements.
Limitations
- The paper states that the mechanism whereby respiratory chain deficiency leads to inclusion formation needs to be elucidated, that there was no evidence of α-synuclein in the inclusions, and that there is no absolute link between respiratory chain dysfunction and oxidative stress.
- The text makes evident that this is a mouse model rather than human PD, that the inclusions differ from human Lewy bodies in α-synuclein content, and that the h116–131 antibody reacted with an unknown inclusion component.
- The paper does not include a formal limitations section; additional limitations evident from the text include reliance on a single conditional knockout model and unresolved specificity of one α-synuclein antibody.
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25 Own result · 11 Own interpretation · 8 Not checked yet · 1 Own method · 1 No basis given
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In the paper
“In situ hybridizations detected much reduced expression of the mtDNA-encoded COX subunit I mRNA in DA neurons of substantia nigra (SN) and the ventral tegmental area (VTA) in MitoPark mice at the age of 6 weeks (Fig. 1E).”
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In the paper
“accompanied by formation of intraneuronal inclusions and dopamine nerve cell death.”
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In the paper
“We also found a marked reduction of COX enzyme activity by histochemical analyses of midbrain DA neurons of 20-week-old MitoPark mice (Fig. 1D).”
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In the paper
“There was no increased embryonic or neonatal lethality in MitoPark mice.”
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In the paper
“However, five additional antibodies (see Methods) directed against α-synuclein were not immunoreactive with the inclusions although they gave rise to expected α-synuclein-like immunoreactivity in nonaffected neurons.”
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In the paper
“accompanied by formation of intraneuronal inclusions and dopamine nerve cell death.”
- Also stated in: § Results · plain
“a majority of them contained small cytoplasmic aggregates (Fig. 4A–D).”
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In the paper
“We found many examples where a mitochondrial marker protein, the nucleus-encoded α-subunit of mitochondrial ATP synthase, partially overlapped with, was juxtaposed to, or even surrounded the inclusions (Fig. 4 E and F).”
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In the paper
“Decreased locomotion and reduced exploratory behavior first became apparent at age ≈14–15 weeks.”
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“The absence of a functional α-synuclein gene had no obvious impact on the phenotype in MitoPark mice (data not shown).”
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In the paper
“Confocal and electron microscopy show that the inclusions contain both mitochondrial protein and membrane components.”
- Also stated in: § Results · hedged
“We found many examples where a mitochondrial marker protein, the nucleus-encoded α-subunit of mitochondrial ATP synthase, partially overlapped with, was juxtaposed to, or even surrounded the inclusions (Fig. 4 E and F).”
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In the paper
“We performed behavioral tests to obtain quantitative measurements of the clinically obvious motor impairment in MitoPark mice and found progressive decline of both locomotion (Fig. 2A–C) and rearing (Fig. 2D) in MitoPark mice from the age of 14 weeks.”
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“However, the DA neurons did not appear normal at this clinically presymptomatic stage, as a majority of them contained small cytoplasmic aggregates (Fig. 4A–D).”
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“Ultrathin sections from the midbrain of MitoPark and control mice at age 11 weeks were examined by electron microscopy. In MitoPark mice only, we observed large, clearly delineated and partially electron-dense bodies often located in dendritic structures close to neuronal somata (Fig. 5).”
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“an identical L-DOPA dose elicited a more pronounced and longer lasting locomotion response in younger in comparison with older MitoPark mice (Fig. 2 E and F).”
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“and MitoPark mice had to be killed at ≈45 weeks of age because of poor general condition.”
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In the paper
“A polyclonal antibody raised against a peptide of human α-synuclein (h116–131), was strongly immunoreactive with the intraneuronal inclusions.”
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In the paper
“which, in turn, leads to a parkinsonism phenotype with adult onset of slowly progressive impairment of motor function accompanied by formation of intraneuronal inclusions and dopamine nerve cell death.”
- Also stated in: § Results · plain
“Decreased locomotion and reduced exploratory behavior first became apparent at age ≈14–15 weeks.”
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“We performed neurochemical studies, which confirmed that the DA nerve cell loss resulted in a corresponding loss of DA in different parts of the nigrostriatal system of 20-week-old MitoPark mice (Fig. 3 J and K).”
boosteddirect- Asserted: passes — The authors put it forward as true.
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In the paper
“Inclusions were not found in non-DA neurons.”
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“These experiments demonstrate that respiratory chain dysfunction in DA neurons may be of pathophysiological importance in PD.”
- Also stated in: § Abstract · hedged
“Our findings thus provide experimental support for the hypothesis that acquired respiratory chain dysfunction may be of pathophysiological importance in PD.”
hedgedconditional- Asserted: passes — The authors put it forward as true.
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- Rests on an assumption: Clinical studies have not established whether respiratory chain deficiency is a primary abnormality leading to inclusion formation and DA neuron death, or whether generalized metabolic abnormalities within degenerating DA neurons cause secondary damage to mitochondria.
- Also stated in: § Abstract · hedged
In the paper
“Mitochondrial dysfunction is implicated in the pathophysiology of Parkinson′s disease (PD), a common age-associated neurodegenerative disease characterized by intraneuronal inclusions (Lewy bodies) and progressive degeneration of the nigrostriatal dopamine (DA) system.”
- Also stated in: § Abstract · hedged
“mitochondrial dysfunction has also been implicated in common forms of age-associated neurodegenerative diseases (2).”
What the sources say
- Not checked yetcites [2] Dauer W, Przedborski S. Neuron. 2003;39:889–909. doi: 10.1016/s0896-6273(03)00568-3. [DOI] [PubMed] [Google Scholar] source
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In the paper
“These data strongly suggest that dysfunctional mitochondria have a direct role in the formation of the intracytoplasmic inclusions.”
- Also stated in: § Discussion · boosted
“We present evidence that dysfunctional mitochondria directly participate in inclusion formation.”
boosteddirect- Asserted: passes — The authors put it forward as true.
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In the paper
“These findings show that there is a severe reduction of mtDNA expression, which, in turn, causes a severe respiratory chain deficiency in midbrain DA neurons of MitoPark mice.”
boosteddirect- Asserted: passes — The authors put it forward as true.
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In the paper
“It should therefore be emphasized that a possible mitochondrial etiology for PD does not automatically mean that reactive oxygen species and oxidative stress are of major importance.”
hedged- Asserted: passes — The authors put it forward as true.
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In the paper
“Gene expression studies in a mouse model with progressive cardiomyopathy, induced by tissue-specific Tfam knockout causing mtDNA depletion, has demonstrated a strong induction of LON-protease expression (14).”
What the sources say
- Not checked yetcites [14] Hansson A, Hance N, Dufour E, Rantanen A, Hultenby K, Clayton DA, Wibom R, Larsson NG. Proc Natl Acad Sci USA. 2004;101:3136–3141. doi: 10.1073/pnas.0308710100. [DOI] [PMC free article] [PubMed] [Google Scholar] source
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None of the sources cited for this claim have been checked yet.
In the paper
“We have studied a variety of mouse models with decreased mtDNA expression (10, 12–18) and such mice have increased cell death with little or no increase of oxidative stress (18, 30).”
What the sources say
- Not checked yetcites [10] Trifunovic A, Wredenberg A, Falkenberg M, Spelbrink JN, Rovio AT, Bruder CE, Bohlooly Y-M, Gidlöf S, Oldfors A, Wibom R, et al. Nature. 2004;429:417–423. doi: 10.1038/nature02517. [DOI] [PubMed] [Google Scholar] source
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plaincorrelational- Asserted: passes — The authors put it forward as true.
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In the paper
“In addition, our results provide experimental support for the hypothesis that reduced mtDNA expression may be an etiological event in PD.”
hedgedconditional- Asserted: passes — The authors put it forward as true.
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- Rests on an assumption: Clinical studies have not established whether respiratory chain deficiency is a primary abnormality leading to inclusion formation and DA neuron death, or whether generalized metabolic abnormalities within degenerating DA neurons cause secondary damage to mitochondria.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“and the MitoPark mice may therefore provide a platform to study key pathophysiological events in PD.”
hedgedconditional- Asserted: passes — The authors put it forward as true.
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In the paper
“However, there is no absolute link between respiratory chain dysfunction and oxidative stress.”
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In the paper
“Reduced mtDNA expression leads to an excess of nucleus-encoded respiratory chain subunits that must be degraded by the mitochondrial proteolytic system.”
plaindirect- Asserted: passes — The authors put it forward as true.
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- Probably not a substantial claim. 6
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In the paper
“Unexpectedly, the inclusions also remained, and were immunoreactive with the h116–131 antibody in the MitoPark mice lacking a functional α-synuclein gene (data not shown).”
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“Quantification of numbers of tyrosine hydroxylase (TH)-expressing midbrain neurons revealed a slow progressive cell loss, which was more marked and had an earlier onset in SN, which predominantly innervates dorsal striatum, in comparison with VTA, which predominantly innervates ventral striatum and cortical areas (Fig. 3 E–I).”
plaincorrelational- Asserted: passes — The authors put it forward as true.
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In the paper
“Loss of DA innervation was first observed in dorsolateral striatum at age 12 weeks and this loss progressed to involve most of the dorsal and ventral striatum as the MitoPark mice became older (Fig. 3A–D).”
plaincorrelational- Asserted: passes — The authors put it forward as true.
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In the paper
“The inclusions were present in most midbrain DA neurons (Fig. 4C) and their mean size increased as neurodegeneration progressed (Fig. 4D).”
plaindirect- Asserted: passes — The authors put it forward as true.
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In the paper
“Some of these bodies had an amorphous content and a diffuse lining, whereas others displayed tubular formations and were surrounded by distinct double layer membranes (Fig. 5 B and C).”
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“In 6-week-old MitoPark mice, there was no observable DA cell loss (Fig. 3F) despite the presence of severely reduced mtDNA expression (Fig. 1E) in midbrain DA neurons.”
plain- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Thus α-synuclein was neither needed for the PD phenotype nor the development of DA neuron inclusions in our mice.”
plain- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
- Rests on an assumption: α-synuclein is commonly found in Lewy bodies in human PD.
In the paper
“Available data show that Lewy bodies can have a variety of morphological shapes (25), and it has been suggested that their morphology evolves with time (25).”
What the sources say
- Not checked yetcites [25] Shults CW. Proc Natl Acad Sci USA. 2006;103:1661–1668. doi: 10.1073/pnas.0509567103. [DOI] [PMC free article] [PubMed] [Google Scholar]
hedgedconditional- Asserted: passes — The authors put it forward as true.
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Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“The morphology of Lewy bodies has mainly been studied in brain tissue obtained from end-stage PD patients, and it is therefore not well established how these aggregates appear at early disease stages.”
plain- Asserted: passes — The authors put it forward as true.
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- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
In the paper
“We used in situ hybridizations (Fig. 1B) and mating to reporter mice (23), which activate the expression of β-galactosidase in cre-expressing cells (Fig. 1C), to establish that DAT-cre mice express cre mRNA and enzymatically active cre-recombinase protein in DA neurons of the midbrain.”
What the sources say
- Not checked yetcites [23] Soriano P. Nat Genet. 1999;21:70–71. doi: 10.1038/5007. [DOI] [PubMed] [Google Scholar]
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This differential degeneration is also characteristic of PD in man.”
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: fails — The paper may give no reason why it holds.
Probably not a substantial claim. The paper may give no reason why it holds.
In the paper
“It has recently been demonstrated that midbrain DA neurons of PD patients and elderly humans contain high levels of somatic mtDNA mutations, which may impair respiratory chain function.”
- Also stated in: § Abstract · boosted
“Analysis of mtDNA mutation levels in DA neurons with normal COX activity has demonstrated very high levels of mtDNA with deletions in both PD patients and aged controls and there was a linear increase of the mutation load with increasing age (7).”
What the sources say
- Not checked yetcites [7] Bender A, Krishnan KJ, Morris CM, Taylor GA, Reeve AK, Perry RH, Jaros E, Hersheson JS, Betts J, Klopstock T, et al. Nat Genet. 2006;38:515–517. doi: 10.1038/ng1769. [DOI] [PubMed] [Google Scholar] source
boostedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Also stated in: § Abstract · boosted
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We demonstrate that respiratory chain deficiency in DA neurons in mice leads to characteristic manifestations of parkinsonism, including slowly progressive neuronal degeneration, typical behavioral disturbances, and the formation of intraneuronal inclusions.”
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“In vitro studies have shown that α-synuclein can interact directly with lipids found in membranes (26, 27) and with proteins of the mitochondrial respiratory chain (28, 29).”
What the sources say
- Not checked yetcites [26] Cole NB, Murphy DD, Grider T, Rueter S, Brasaemle D, Nussbaum RL. J Biol Chem. 2002;277:6344–6352. doi: 10.1074/jbc.M108414200. [DOI] [PubMed] [Google Scholar]
- Not checked yetcites [27] Ellis CE, Murphy EJ, Mitchell DC, Golovko MY, Scaglia F, Barcelo-Coblijn GC, Nussbaum RL. Mol Cell Biol. 2005;25:10190–10201. doi: 10.1128/MCB.25.22.10190-10201.2005. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Not checked yetcites [28] Hashimoto M, Takeda A, Hsu LJ, Takenouchi T, Masliah E. J Biol Chem. 1999;274:28849–28852. doi: 10.1074/jbc.274.41.28849. [DOI] [PubMed] [Google Scholar]
- Not checked yetcites [29] Elkon H, Don J, Melamed E, Ziv I, Shirvan A, Offen D. J Mol Neurosci. 2002;18:229–238. doi: 10.1385/JMN:18:3:229. [DOI] [PubMed] [Google Scholar]
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“TH-immunoreactive DA nerve cell body profiles were counted on coded slides at representative levels of SN and VTA, respectively, using two to five sections per animal and a total of 18 mice (nine littermate pairs, each consisting of one MitoPark and one control).”
plainn = 18- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
In the paper
“The mitochondrial network has an elaborate system for protein degradation involving membrane bound AAA-proteases and LON protease in the matrix (31).”
What the sources say
- Not checked yetcites [31] Rugarli EI, Langer T. Trends Mol Med. 2006;12:262–269. doi: 10.1016/j.molmed.2006.04.002. [DOI] [PubMed] [Google Scholar]
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
The paper relies on this without support.
Clinical studies have not established whether respiratory chain deficiency is a primary abnormality leading to inclusion formation and DA neuron death, or whether generalized metabolic abnormalities within degenerating DA neurons cause secondary damage to mitochondria.
“However, clinical studies have not established whether the respiratory chain deficiency is a primary abnormality leading to inclusion formation and DA neuron death, or whether generalized metabolic abnormalities within the degenerating DA neurons cause secondary damage to mitochondria.”
The paper relies on this without support.
α-synuclein is commonly found in Lewy bodies in human PD.
“However, we did not find evidence of α-synuclein in these inclusions, although α-synuclein is commonly found in Lewy bodies in human PD.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the citing paper
“For all the targeted cell types, TFAM depletion leads to mtDNA depletion (not reported for midbrain DA neurons), mitochondrial transcript depletion (not reported for midbrain DA neurons) and respiratory chain deficiency, suggesting that TFAM is essential for mtDNA maintenance in vivo”
From Role of the mitochondrial DNA replication machinery in mitochondrial DNA mutagenesis, aging and age-related diseases (2017) · cites this paper as Ekstrand et al., 2007
In the citing paper
“TFAM deletion in mouse pyramidal neurons causes mitochondrial late-onset neurodegeneration (MILON) (Sorensen et al., 2001) whereas deletion in mouse midbrain DA neurons leads to PD (Ekstrand et al., 2007).”
From Role of the mitochondrial DNA replication machinery in mitochondrial DNA mutagenesis, aging and age-related diseases (2017) · cites this paper as Ekstrand et al., 2007
In the citing paper
“Alternative and more successful approaches to developing mouse models of mitochondrial disease involve manipulating the nuclear genes that regulate mtDNA maintenance and replication, such as TFAM [176][177][178][179][180][181][182], POLG ('Mutator' model) [183], and PEO1 (Twinkle; 'Deletor' model) [184].”
From Mitochondrial DNA mutations and human disease (2010) · cites this paper as [177]
Citations
Cites
Dauer, W., & Przedborski, S. (2003) · Neuron · doi:10.1016/s0896-6273(03)00568-3 · Cited by 5,469
Generalized lacZ expression with the ROSA26 Cre reporter strain
Soriano, P. (1999) · Nature Genetics · doi:10.1038/5007 · Cited by 5,237
Premature ageing in mice expressing defective mitochondrial DNA polymerase
Trifunovic, A., Wredenberg, A., Falkenberg, M., Spelbrink, J. N., Rovio, A. T., Bruder, C. E., Bohlooly-Y, M., Gidlöf, S., Oldfors, A., Wibom, R., et al. (2004) · Nature · doi:10.1038/nature02517 · Cited by 2,734
Self-citationDrosophila pink1 is required for mitochondrial function and interacts genetically with parkin
Clark, I. E., Dodson, M. W., Jiang, C., Cao, J. H., Huh, J. R., Seol, J. H., Yoo, S. J., Hay, B. A., & Guo, M. (2006) · Nature · doi:10.1038/nature04779 · Cited by 1,788
Mitochondrial dysfunction in Drosophila PINK1 mutants is complemented by parkin
Park, J., Lee, S. B., Lee, S., Kim, Y., Song, S., Kim, S., Bae, E., Kim, J., Shong, M., Kim, J.-M., et al. (2006) · Nature · doi:10.1038/nature04788 · Cited by 1,705
Mitochondrial transcription factor A is necessary for mtDNA maintance and embryogenesis in mice
Larsson, N.-G., Wang, J., Wilhelmsson, H., Oldfors, A., Rustin, P., Lewandoski, M., Barsh, G. S., & Clayton, D. A. (1998) · Nature Genetics · doi:10.1038/ng0398-231 · Cited by 1,594
Self-citationBender, A., Krishnan, K. J., Morris, C. M., Taylor, G. A., Reeve, A. K., Perry, R. H., Jaros, E., Hersheson, J. S., Betts, J., Klopstock, T., et al. (2006) · Nature Genetics · doi:10.1038/ng1769 · Cited by 1,570
Mitochondrial transcription factor A regulates mtDNA copy number in mammals
Ekstrand, M. I. (2004) · Human Molecular Genetics · doi:10.1093/hmg/ddh109 · Cited by 919
Self-citationVolkow, N. D., Wang, G.-J., Fowler, J. S., Gatley, S. J., Logan, J., Ding, Y.-S., Hitzemann, R., & Pappas, N. (1998) · American Journal of Psychiatry · doi:10.1176/ajp.155.10.1325 · Cited by 885
Cabin, D. E., Shimazu, K., Murphy, D., Cole, N. B., Gottschalk, W., McIlwain, K. L., Orrison, B., Chen, A., Ellis, C. E., Paylor, R., et al. (2002) · The Journal of Neuroscience · doi:10.1523/jneurosci.22-20-08797.2002 · Cited by 865
Research works printed but not linked: 1
- H Andersson, J Luthman, E Lindqvist, L Olson Neurotoxicology 16, 201–210 (1995).
Cited by
Sorted by citations
Poewe, W., Seppi, K., Tanner, C. M., Halliday, G. M., Brundin, P., Volkmann, J., Schrag, A.-E., & Lang, A. E. (2017) · Nature Reviews Disease Primers · doi:10.1038/nrdp.2017.13 · Cited by 5,415
PINK1 Is Selectively Stabilized on Impaired Mitochondria to Activate Parkin
Narendra, D. P., Jin, S. M., Tanaka, A., Suen, D.-F., Gautier, C. A., Shen, J., Cookson, M. R., & Youle, R. J. (2010) · PLoS Biology · doi:10.1371/journal.pbio.1000298 · Cited by 2,944
The gut microbiota–brain axis in behaviour and brain disorders
Morais, L. H., Schreiber, H. L., & Mazmanian, S. K. (2021) · Nature Reviews Microbiology · doi:10.1038/s41579-020-00460-0 · Cited by 2,149
Mitophagy and Quality Control Mechanisms in Mitochondrial Maintenance
Pickles, S., Vigié, P., & Youle, R. J. (2018) · Current Biology · doi:10.1016/j.cub.2018.01.004 · Cited by 2,081
Autophagy, mitochondria and oxidative stress: cross-talk and redox signalling.
Lee, J., Giordano, S., & Zhang, J. (2012) · Biochemical Journal · doi:10.1042/bj20111451 · Cited by 1,438
Metadata
- Authors
- Ekstrand, M. I., Terzioglu, M., Galter, D., Zhu, S., Hofstetter, C., Lindqvist, E., Thams, S., Bergstrand, A., Hansson, F. S., Trifunovic, A., Hoffer, B., Cullheim, S., Mohammed, A. H., Olson, L., & Larsson, N.-G.
- Affiliations
- Karolinska University Hospital (SE)
- Department of Laboratory Medicine and
- Karolinska Institutet (SE)
- National Institutes of Health (US)
- Corresponding author
- Larsson, Nils-Göran
- ORCID
- Venue
- Proceedings of the National Academy of Sciences
- Publisher
- National Academy of Sciences
- Published
- 2007-01-23
- Volume
- 104
- Issue
- 4
- Pages
- 1325-1330
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- PMC
- PMC1783140
- OpenAlex
- W2055557007
- Semantic Scholar
- eae41525f2f96b0fa42114d58d84dc3353e90137
- Cited by
- 605
- References
- 33
- Citations by year
- 2026: 20 · 2025: 25 · 2024: 35 · 2023: 32 · 2022: 25 · 2021: 33 · 2020: 40 · 2019: 34 · 2018: 38 · 2017: 28 · 2016: 19 · 2015: 32 · 2014: 31 · 2013: 32 · 2012: 29
- FWCI
- 23.38
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Proceedings of the National Academy of Sciences (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Michael J. Fox Foundation for Parkinson's Research
- Karolinska Institutet
- Vetenskapsrådet
- Swedish Brain Power
- National Institutes of Health
- U.S. Public Health Service
- Parkinsonfonden
- Topics
- Health Sciences › Medicine › Clinical Neurology › Parkinson's Disease Mechanisms and Treatments
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Mitochondrial Function and Pathology
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Nuclear Receptors and Signaling
- Keywords
- Parkinson's disease, mitochondrial dysfunction, respiratory chain deficiency, dopaminergic neurons, midbrain, Lewy bodies, TFAM, mitochondrial DNA mutations, conditional knockout mice, parkinsonism, motor impairment, intraneuronal inclusions
- MeSH terms
- Animals, Base Sequence, Dopamine, Electron Transport, Immunohistochemistry, Microscopy, Electron, Neurons, DNA Probes, In Situ Hybridization, Parkinsonian Disorders, Mice
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
A language model drew the claims from the paper on 2026-10-10, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).
A second model labelled each claim on 2026-10-10 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
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