Dopaminergic denervation in patients with Parkinson's disease is associated with changes in brain metabolism. Cerebral in-vivo mapping of glucose metabolism has been studied in severe stable parkinsonian monkeys, but data on brain metabolic changes in early stages of dopaminergic depletion of this model is lacking. Here, we report cerebral metabolic changes associated with progressive nigrostriatal lesion in the pre-symptomatic and symptomatic stages of the progressive 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) monkey model of Parkinson's Disease. Monkeys (Macaca fascicularis) received MPTP injections biweekly to induce progressive grades of dopamine depletion. Monkeys were sorted according to motor scale assessments in control, asymptomatic, recovered, mild, and severe parkinsonian groups. Dopaminergic depletion in the striatum and cerebral metabolic patterns across groups were studied in vivo by positron emission tomography (PET) using monoaminergic ([11C]-dihydrotetrabenazine; 11C-DTBZ) and metabolic (2-[18F]-fluoro-2-deoxy-d-glucose; 18F-FDG) radiotracers. 11C-DTBZ-PET analysis showed progressive decrease of binding potential values in the striatum of monkeys throughout MPTP administration and the development of parkinsonian signs. 18F-FDG analysis in asymptomatic and recovered animals showed significant hypometabolism in temporal and parietal areas of the cerebral cortex in association with moderate dopaminergic nigrostriatal depletion. Cortical hypometabolism extended to involve a larger area in mild parkinsonian monkeys, which also exhibited hypermetabolism in the globus pallidum pars interna and cerebellum. In severe parkinsonian monkeys, cortical hypometabolism extended further to lateral-frontal cortices and hypermetabolism also ensued in the thalamus and cerebellum. Unbiased histological quantification of neurons in Brodmann's area 7 in the parietal cortex did not reveal neuron loss in parkinsonian monkeys versus controls. Early dopaminergic nigrostriatal depletion is associated with cortical, mainly temporo-parietal hypometabolism unrelated to neuron loss. These findings, together with recent evidence from Parkinson's Disease patients, suggest that early cortical hypometabolism may be associated and driven by subcortical changes that need to be evaluated appropriately. Altogether, these findings could be relevant when potential disease modifying therapies become available.

The success of cell therapy for the treatment of myocardial infarction depends on finding novel approaches that can substantially implement the engraftment of the transplanted cells. In order to enhance cell engraftment, most studies have focused on the pretreatment of transplantable cells. Here we have considered an alternative approach that involves the preconditioning of infarcted heart tissue to reduce endogenous cell activity and thus provide an advantage to our exogenous cells. This treatment is routinely used in other tissues such as bone marrow and skeletal muscle to improve cell engraftment, but it has never been taken in cardiac tissue. To avoid long-term cardiotoxicity induced by full heart irradiation we developed a rat model of a catheter-based heart irradiation system to locally impact a delimited region of the infarcted cardiac tissue. As proof of concept, we transferred ZsGreen(+) iPSCs in the infarcted heart, due to their ease of use and detection. We found a very significant increase in cell engraftment in preirradiated rats. In this study, we demonstrate for the first time that preconditioning the infarcted cardiac tissue with local irradiation can substantially enhance cell engraftment.

BACKGROUND: Cardiac fibroblasts (CFs) have a central role in the ventricular remodeling process associated with different types of fibrosis. Recent studies have shown that fibroblasts do not respond homogeneously to heart injury. Because of the limited set of bona fide fibroblast markers, a proper characterization of fibroblast population heterogeneity in response to cardiac damage is lacking. The purpose of this study was to define CF heterogeneity during ventricular remodeling and the underlying mechanisms that regulate CF function. METHODS: Collagen1 alpha 1-GFP (green fluorescent protein)-positive CFs were characterized after myocardial infarction (MI) by single-cell and bulk RNA sequencing, assay for transposase-accessible chromatin sequencing, and functional assays. Swine and patient samples were studied using bulk RNA sequencing. RESULTS: We identified and characterized a unique CF subpopulation that emerges after MI in mice. These activated fibroblasts exhibit a clear profibrotic signature, express high levels of Cthrc1 (collagen triple helix repeat containing 1), and localize into the scar. Noncanonical transforming growth factor-beta signaling and different transcription factors including SOX9 are important regulators mediating their response to cardiac injury. Absence of CTHRC1 results in pronounced lethality attributable to ventricular rupture. A population of CFs with a similar transcriptome was identified in a swine model of MI and in heart tissue from patients with MI and dilated cardiomyopathy. CONCLUSIONS: We report CF heterogeneity and their dynamics during the course of MI and redefine the CFs that respond to cardiac injury and participate in myocardial remodeling. Our study identifies CTHRC1 as a novel regulator of the healing scar process and a target for future translational studies.

In the treatment of bone non-unions, an alternative to bone autografts is the use of bone morphogenetic proteins (BMPs), e.g., BMP-2, BMP-7, with powerful osteoinductive and osteogenic properties. In clinical settings, these osteogenic factors are applied using absorbable collagen sponges for local controlled delivery. Major side effects of this strategy are derived from the supraphysiological doses of BMPs needed, which may induce ectopic bone formation, chronic inflammation, and excessive bone resorption. In order to increase the efficiency of the delivered BMPs, we designed cryostructured collagen scaffolds functionalized with hydroxyapatite, mimicking the structure of cortical bone (aligned porosity, anisotropic) or trabecular bone (random distributed porosity, isotropic). We hypothesize that an anisotropic structure would enhance the osteoconductive properties of the scaffolds by increasing the regenerative performance of the provided rhBMP-2. In vitro, both scaffolds presented similar mechanical properties, rhBMP-2 retention and delivery capacity, as well as scaffold degradation time. In vivo, anisotropic scaffolds demonstrated better bone regeneration capabilities in a rat femoral critical-size defect model by increasing the defect bridging. In conclusion, anisotropic cryostructured collagen scaffolds improve bone regeneration by increasing the efficiency of rhBMP-2 mediated bone healing.

Neuregulin-1 loaded poly(lactic-co-glycolic acid) (PLGA) microparticles hold great promise for treating acute myocardial infarction, as they have been proved to recover heart function and induce positive heart remodelling in preclinical studies. More recently, the inflammatory response of the heart after acute myocardial infarction (AMI) has been identified as one of the major mechanisms in cardiac tissue remodelling and repair. However, the connection between neuregulin-1 PLGA microparticles and inflammation is still not well characterised. In the present study we assessed this relationship in a mouse AMI model. First, in vitro evidence indicated that neuregulin-1 PLGA microparticles induced a macrophage polarisation toward a regenerative phenotype (CD206+ cells), preventing macrophages from evolving toward the inflammatory phenotype (B7-2+ cells). This correlated with in vivo experiments, where neuregulin-1 PLGA microparticles locally improved the CD206+/B7-2+ ratio. Moreover, neuregulin-1 PLGA microparticles were administered at different time points (15¿min, 24, 72 and 168¿h) after infarction induction without causing secondary inflammatory issues. The time of treatment administration did not alter the inflammatory response. Taken together, these results suggest that neuregulin-1 PLGA microparticles can be administered depending on the therapeutic window of the encapsulated drug and that they enhance the heart's reparative inflammatory response after acute myocardial infarction, helping cardiac tissue repair.

Islet-1 (Isl1) is a transcription factor essential for life expressed in specific cells with different developmental origins. We have generated iPSC lines from fibroblasts of the transgenic Ai6 x Isl1-Cre (Ai6IslCre) mouse. Here we describe the complete characterization of four iPSC lines: ATCi-Ai6IslCre10, ATCi-Ai6IslCre35, ATCi-Ai6IslCre74 and ATCi-Ai6IslCre80.

We generated a rat iPSC line called ATCi-rSD95 from transgenic Sprague-Dawley GFP fetal fibroblasts. Established ATCi-rSD95 cells present a normal karyotype, silencing of the transgenes and express pluripotency-associated markers. Additionally, ATCi-rSD95 cells are able to form teratoma with differentiated cells derived from the three germ-layers that maintain the GFP expression.

We generated ATCi-MF1 induced pluripotent stem (iPS) cell line from Macaca fascicularis adult skin fibroblasts using non-integrative Sendai viruses carrying OCT3/4, KLF4, SOX2 and c-MYC. Once established, ATCi-MF1 cells present a normal karyotype, are Sendai virus-free and express pluripotency associated markers. Microsatellite markers analysis confirmed the origin of the iPS cells from the parental fibroblasts. Pluripotency was tested with the in vivo teratoma formation assay. ATCi-MF1 cell line may be a useful primate iPS cell model to test different experimental conditions where the use of human cells can imply ethical issues, as microinjection of pluripotent stem cells in pre-implantational embryos.

We generated two rat embryonic stem cell (ESC) lines: ATCe-SD7.8 from Sprague-Dawley strain and ATCe-WK1 from Wistar Kyoto strain. Cells were marked with enhanced green fluorescent protein (eGFP) by transduction with a lentiviral vector. Cells present a normal karyotype and express pluripotency-associated markers. Pluripotency was tested in vivo with the teratoma formation assay. Cells maintain eGFP expression upon differentiation to the three-germ layers. These cells can be a useful tool for cell therapy studies and chimera generation as they can be easily tracked by eGFP expression.

The pathological hallmark of Parkinson's disease (PD) is the progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc), and the resulting striatal dopamine deficiency, which are responsible for the classic motor features. Although a diagnosis of PD relies on the clinical effects of dopamine deficiency, this disease is also associated with other neurotransmitter deficits that are recognized as causing various motor and non-motor symptoms. However, the cause of dopaminergic nigral neurodegeneration in PD and the underlying mechanisms remain unknown. While animal models are considered valuable tools with which to investigate dopaminergic cell vulnerability, rodent models usually fail to mimic the neurodegeneration progression that occurs in human PD. To find a convenient rat model for studying the progression of dopaminergic cell degeneration and motor signs, we have developed a progressive rodent model using a repeated daily, intraventricular administration of the neurotoxin 6-hydroxydopamine (6-OHDA) (100 mu g/day) in awakened rats for 1 to 10 consecutive days. The short-(6-day) and long-term (32-day) progression of motor alterations was studied. This model leads to a bilateral and progressive increase in catalepsy (evident from the 3rd infusion in the short-term groups (p < 0.01) and from the 7th infusion in the long-term groups (p < 0.01), which was associated with a progressive nigrostriatal dopaminergic deficit. All together this makes the new model an interesting experimental tool to investigate the mechanisms involved in the progression of dopaminergic neurodegeneration. (C) 2017 Published by Elsevier Ltd on behalf of IBRO.