Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Sep;4(9):1073-85.
doi: 10.5966/sctm.2015-0023. Epub 2015 Jul 21.

Intracarotid Infusion of Mesenchymal Stem Cells in an Animal Model of Parkinson's Disease, Focusing on Cell Distribution and Neuroprotective and Behavioral Effects

Silvia Cerri  1 , Rosaria Greco  1 , Giovanna Levandis  1 , Cristina Ghezzi  1 , Antonina Stefania Mangione  1 , Marie-Therese Fuzzati-Armentero  1 , Arianna Bonizzi  1 , Maria Antonietta Avanzini  1 , Rita Maccario  1 , Fabio Blandini  2
Affiliations

Intracarotid Infusion of Mesenchymal Stem Cells in an Animal Model of Parkinson's Disease, Focusing on Cell Distribution and Neuroprotective and Behavioral Effects

Silvia Cerri et al. Stem Cells Transl Med. 2015 Sep.

Abstract

Mesenchymal stem cells (MSCs) have been proposed as a potential therapeutic tool for Parkinson's disease (PD) and systemic administration of these cells has been tested in preclinical and clinical studies. However, no information on survival and actual capacity of MSCs to reach the brain has been provided. In this study, we evaluated homing of intraarterially infused rat MSCs (rMSCs) in the brain of rats bearing a 6-hydroxydopamine (6-OHDA)-induced lesion of the nigrostriatal tract, to establish whether the toxin-induced damage is sufficient to grant MSC passage across the blood-brain barrier (BBB) or if a transient BBB disruption is necessary. The rMSC distribution in peripheral organs and the effects of cell infusion on neurodegenerative process and motor deficits were also investigated. rMSCs were infused 14 days after 6-OHDA injection. A hyperosmolar solution of mannitol was used to transiently permeabilize the BBB. Behavioral impairment was assessed by adjusting step test and response to apomorphine. Animals were sacrificed 7 and 28 days after cell infusion. Our work shows that appreciable delivery of rMSCs to the brain of 6-OHDA-lesioned animals can be obtained only after mannitol pretreatment. A notable percentage of infused cells accumulated in peripheral organs. Infusion of rMSCs did not modify the progression of 6-OHDA-induced damage or the motor impairment at the stepping test, but induced progressive normalization of the pathological response (contralateral turning) to apomorphine administration. These findings suggest that many aspects should be further investigated before considering any translation of MSC systemic administration into the clinical setting for PD treatment.

Significance: This study demonstrates that mesenchymal stem cells infused through the carotid artery do not efficiently cross the blood-brain barrier in rats with a Parkinson's disease-like degeneration of nigrostriatal neurons, unless a permeabilizing agent (e.g., mannitol) is used. The infusion did not reduce the neuronal damage and associated motor impairment, but abolished the motor abnormalities these animals typically show when challenged with a dopaminergic agonist. Therefore, although arterially infused mesenchymal stem cells did not show neurorestorative effects in this study's Parkinson's disease model, they appeared to normalize the pathological responsiveness of striatal neurons to dopaminergic stimulation. This capability should be further explored in future studies.

Keywords: Behavioral analyses; Intracarotid infusion; Mannitol; Mesenchymal stem cells; Neuroprotection; Parkinson’s disease.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Experimental design. Fourteen days after stereotaxic injection of 6-OHDA into the striatum, animals had undergone rMSCs or saline/heparin infusion, preceded by transient blood-brain barrier (BBB) disruption procedure. Animals were sacrificed 7 or 28 days after infusion of cells (or saline/heparin). Stepping and apomorphine tests were performed during the entire course of the experiments and the day of the animal sacrifice, respectively. Abbreviations: 6-OHDA, 6-hydroxydopamine; BBB, blood-brain barrier; rMSC, rat mesenchymal stem cell.
Figure 2.
Figure 2.
Effect of mannitol on BBB permeability in the intrastriatal 6-hydroxydopamine rat model. Representative photomicrographs of brain coronal sections showing Evans Blue extravasation in animals (A) W/O and (B) with 25% mannitol pretreatment. The right hemisphere (ipsilateral to intracarotid infusion) was strongly stained by EB dye in the rats receiving mannitol. (C): The administration of mannitol resulted in increased (42%) BBB permeability. Results (mean ± SEM) indicate the percentage of stained volume compared with the total volume of the ipsilateral hemisphere. Abbreviations: BBB, blood-brain barrier; EB, Evans Blue; W/O, without.
Figure 3.
Figure 3.
Effect of rMSC infusion on motor deficits and apomorphine-induced rotational behavior. (A): All 6-OHDA animals exhibited a decline in motor performance after the lesion. The infusion of rMSCs did not improve the motor deficits induced by 6-OHDA injection. Cell infusion per se had no effect on motor performance in sham animals. Results (mean ± SEM) indicate the average number of adjusting steps of the contralateral paw in the “forehand step” direction, carried out by animals during the 6 weeks of behavioral testing. Two-way ANOVA (time) F = 7.754, p < .0001, (treatment) F = 160.0, p < .0001; ∗∗∗, p < .001 Bonferroni post hoc test versus sham/mannitol/rMSCs (weeks 1–6, for both 6-OHDA groups). (B): Lesioned animals that did not receive rMSC transplantation exhibited a remarkable contralateral behavior after apomorphine administration, both 1 and 4 weeks after infusion procedure. Conversely, moderate ipsilateral turning in response to dopaminergic stimulation was observed in the group that received rMSCs 7 days after rMSC administration; no rotational response was observed 28 days post-rMSC infusion. No turning behavior was detected in unlesioned, transplanted animals. Bars represent the mean (± SEM) number of total net rotations (contralateral minus ipsilateral rotations) performed by the animals in 45 minutes. Two-way ANOVA (time) F = 0.9739, p = .3316; (treatment) F = 70.72, p < .0001; Bonferroni post hoc test (7 and 28 days after rMSCs infusion). ∗, p < .05, ∗∗∗, p < .001 versus sham/mannitol/rMSCs; °°°, p < .001 versus 6-OHDA/mannitol. Abbreviations: 6-OHDA, 6-hydroxydopamine; ANOVA, analysis of variance; rMSC, rat mesenchymal stem cell; SHAM, unlesioned.
Figure 4.
Figure 4.
Evaluation of 6-OHDA-induced nigrostriatal neurodegeneration. The intracarotid infusion of rMSCs did not affect the extent of 6-OHDA-induced neurodegeneration both in the short term (7 days) and long term (28 days) after infusion. (A): Representative photomicrographs of brain coronal sections showing striatal TH-positive terminals in both hemispheres. Scale bar: 500 µm. (B): Results (mean ± SEM) indicate the percentage of TH expression in the right striatum (injected with 6-OHDA) compared with the left, unlesioned striatum of rats that received an rMSCs infusion or saline/heparin. (C): Representative photomicrographs of brain coronal sections showing TH-positive cells of the SNc of both hemispheres. Scale bar: 500 µm. (D, E): Stereological counts of dopaminergic neurons in the SNc of rats that received an rMSCs infusion or saline/heparin. The number of dopaminergic neurons in the SNc is indicated (D) as the absolute number of TH-positive cells in the nonlesioned and lesioned hemisphere and (E) as the percentage of surviving neurons in the lesioned SNc compared with the intact SNc. Abbreviations: 6-OHDA, 6-hydroxydopamine; rMSC, rat mesenchymal stem cell; SNc, substantia nigra pars compacta; TH, tyrosine hydroxylase.
Figure 5.
Figure 5.
Whole-body distribution of rMSCs in the intrastriatal 6-OHDA rat model. At the moment of sacrifice, peripheral organs were excised and underwent near-IR imaging to evaluate the distribution of NIR815-positive rMSCs. (A): In the absence of mannitol treatment, no remarkable rMSC signal is detected into the brain of 6-OHDA animals. (B): A speckled NIR815-positive signal (arrowhead) is visible within the brain parenchyma ipsilateral to the ici, in the animal group that underwent transient blood-brain barrier disruption. (C): Negative control (no rMSC infusion). Unlike the brain, lung and spleen of rats receiving rMSCs, with (B) or without (A) mannitol pretreatment, show an intense NIR signal. Images represent the actual size of the organs and are equally representative of both time points chosen (7 and 28 days) after cell infusion. Bright green signal, NIR815. Abbreviations: 6-OHDA, 6-hydroxydopamine; ici, intracarotid infusion; NIR, near-infrared; NIR815, near-infrared 815-nm spectrum; rMSC, rat mesenchymal stem cell.
Figure 6.
Figure 6.
Quantitative analysis of rMSC distribution in the brain of 6-hydroxydopamine rat model. Seven and 28 days after rMSC infusion, tissue sections of the brain were examined under a fluorescent microscope and cells were counted along the entire rostrocaudal axis, in both hemispheres. (A): Mannitol pretreatment significantly enhanced the passage of rMSCs across the blood-brain barrier. Results (mean ± SEM) represent the estimated absolute number of the rMSCs engrafted into the brain. (B, C): In the animals pretreated with mannitol, infused rMSCs spread to both hemispheres, although they preferentially localized in the hemisphere ipsilateral to the intracarotid infusion. This tendency was more evident at 7 days after infusion, and slightly reduced over time. Bar graphs show the distribution of cells within striatum and substantia nigra in both hemispheres; both the estimated absolute number and the percentage of engrafted cells with respect of total cells infused (in brackets) were reported. ∗, p < .05 Kruskal-Wallis test versus W/O mannitol infusion. Abbreviations: 6-OHDA, 6-hydroxydopamine; rMSC, rat mesenchymal stem cell; W/O, without.
Figure 7.
Figure 7.
Central distribution of rat mesenchymal stem cells (rMSCs) in the intrastriatal 6-hydroxydopamine rat model. Tissue sections of the brain were examined under a fluorescent microscope for tracking cell distribution along the entire rostrocaudal axis, in both hemispheres. The figure shows a graphical representation of cell distribution in the animal group pretreated with mannitol, at 7 days after rMSC infusion. Infused rMSCs showed a scattered arrangement in both hemispheres, with a prevailing tendency to localize in the hemisphere ipsilateral to the intracarotid infusion, especially in the forebrain. Red signal, PKH26; bright green signal, NIR815; blue signal, DAPI. Scale bar: 20 µm. Abbreviation: DAPI, 4',6-diamidino-2-phenylindole; NIR815, near-infrared 815-nm spectrum.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Defer GL, Geny C, Ricolfi F, et al. Long-term outcome of unilaterally transplanted parkinsonian patients. I. Clinical approach. Brain. 1996;119:41–50. - PubMed
    1. Freed CR, Breeze RE, Rosenberg NL, et al. Survival of implanted fetal dopamine cells and neurologic improvement 12 to 46 months after transplantation for Parkinson’s disease. N Engl J Med. 1992;327:1549–1555. - PubMed
    1. Lindvall O, Brundin P, Widner H, et al. Grafts of fetal dopamine neurons survive and improve motor function in Parkinson’s disease. Science. 1990;247:574–577. - PubMed
    1. Madrazo I, León V, Torres C, et al. Transplantation of fetal substantia nigra and adrenal medulla to the caudate nucleus in two patients with Parkinson’s disease. N Engl J Med. 1988;318:51. - PubMed
    1. Björklund LM, Sánchez-Pernaute R, Chung S, et al. Embryonic stem cells develop into functional dopaminergic neurons after transplantation in a Parkinson rat model. Proc Natl Acad Sci USA. 2002;99:2344–2349. - PMC - PubMed

Publication types

MeSH terms

LinkOut - more resources