scholarly journals Interaction of Neuromelanin with Xenobiotics and Consequences for Neurodegeneration; Promising Experimental Models

Antioxidants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 824
Author(s):  
Andrea Capucciati ◽  
Fabio A. Zucca ◽  
Enrico Monzani ◽  
Luigi Zecca ◽  
Luigi Casella ◽  
...  

Neuromelanin (NM) accumulates in catecholamine long-lived brain neurons that are lost in neurodegenerative diseases. NM is a complex substance made of melanic, peptide and lipid components. NM formation is a natural protective process since toxic endogenous metabolites are removed during its formation and as it binds excess metals and xenobiotics. However, disturbances of NM synthesis and function could be toxic. Here, we review recent knowledge on NM formation, toxic mechanisms involving NM, go over NM binding substances and suggest experimental models that can help identifying xenobiotic modulators of NM formation or function. Given the high likelihood of a central NM role in age-related human neurodegenerative diseases such as Parkinson’s and Alzheimer’s, resembling such diseases using animal models that do not form NM to a high degree, e.g., mice or rats, may not be optimal. Rather, use of animal models (i.e., sheep and goats) that better resemble human brain aging in terms of NM formation, as well as using human NM forming stem cellbased in vitro (e.g., mid-brain organoids) models can be more suitable. Toxicants could also be identified during chemical synthesis of NM in the test tube.

Biomedicines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1635
Author(s):  
Chuan-Chuan Chao ◽  
Po-Wen Shen ◽  
Tsai-Yu Tzeng ◽  
Hsing-Jien Kung ◽  
Ting-Fen Tsai ◽  
...  

With an increased life expectancy among humans, aging has recently emerged as a major focus in biomedical research. The lack of in vitro aging models—especially for neurological disorders, where access to human brain tissues is limited—has hampered the progress in studies on human brain aging and various age-associated neurodegenerative diseases at the cellular and molecular level. In this review, we provide an overview of age-related changes in the transcriptome, in signaling pathways, and in relation to epigenetic factors that occur in senescent neurons. Moreover, we explore the current cell models used to study neuronal aging in vitro, including immortalized cell lines, primary neuronal culture, neurons directly converted from fibroblasts (Fib-iNs), and iPSC-derived neurons (iPSC-iNs); we also discuss the advantages and limitations of these models. In addition, the key phenotypes associated with cellular senescence that have been observed by these models are compared. Finally, we focus on the potential of combining human iPSC-iNs with genome editing technology in order to further our understanding of brain aging and neurodegenerative diseases, and discuss the future directions and challenges in the field.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 207
Author(s):  
Diane L. Ritchie ◽  
Marcelo A. Barria

The accumulation and propagation in the brain of misfolded proteins is a pathological hallmark shared by many neurodegenerative diseases such as Alzheimer’s disease (Aβ and tau), Parkinson’s disease (α-synuclein), and prion disease (prion protein). Currently, there is no epidemiological evidence to suggest that neurodegenerative disorders are infectious, apart from prion diseases. However, there is an increasing body of evidence from experimental models to suggest that other pathogenic proteins such as Aβ and tau can propagate in vivo and in vitro in a prion-like mechanism, inducing the formation of misfolded protein aggregates such as amyloid plaques and neurofibrillary tangles. Such similarities have raised concerns that misfolded proteins, other than the prion protein, could potentially transmit from person-to-person as rare events after lengthy incubation periods. Such concerns have been heightened following a number of recent reports of the possible inadvertent transmission of Aβ pathology via medical and surgical procedures. This review will provide a historical perspective on the unique transmissible nature of prion diseases, examining their impact on public health and the ongoing concerns raised by this rare group of disorders. Additionally, this review will provide an insight into current evidence supporting the potential transmissibility of other pathogenic proteins associated with more common neurodegenerative disorders and the potential implications for public health.


Biomolecules ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 173 ◽  
Author(s):  
Wassim Fhayli ◽  
Quentin Boëté ◽  
Nadjib Kihal ◽  
Valérie Cenizo ◽  
Pascal Sommer ◽  
...  

Elastic fibers (90% elastin, 10% fibrillin-rich microfibrils) are synthesized only in early life and adolescence mainly by the vascular smooth muscle cells through the cross-linking of its soluble precursor, tropoelastin. Elastic fibers endow the large elastic arteries with resilience and elasticity. Normal vascular aging is associated with arterial remodeling and stiffening, especially due to the end of production and degradation of elastic fibers, leading to altered cardiovascular function. Several pharmacological treatments stimulate the production of elastin and elastic fibers. In particular, dill extract (DE) has been demonstrated to stimulate elastin production in vitro in dermal equivalent models and in skin fibroblasts to increase lysyl oxidase–like-1 (LOXL-1) gene expression, an enzyme contributing to tropoelastin crosslinking and elastin formation. Here, we have investigated the effects of a chronic treatment (three months) of aged male mice with DE (5% or 10% v/v, in drinking water) on the structure and function of the ascending aorta. DE treatment, especially at 10%, of aged mice protected pre-existing elastic lamellae, reactivated tropoelastin and LOXL-1 expressions, induced elastic fiber neo-synthesis, and decreased the stiffness of the aging aortic wall, probably explaining the reversal of the age-related cardiac hypertrophy also observed following the treatment. DE could thus be considered as an anti-aging product for the cardiovascular system.


Gerontology ◽  
2016 ◽  
Vol 63 (2) ◽  
pp. 103-117 ◽  
Author(s):  
Cia-Hin Lau ◽  
Yousin Suh

The recent advent of genome and epigenome editing technologies has provided a new paradigm in which the landscape of the human genome and epigenome can be precisely manipulated in their native context. Genome and epigenome editing technologies can be applied to many aspects of aging research and offer the potential to develop novel therapeutics against age-related diseases. Here, we discuss the latest technological advances in the CRISPR-based genome and epigenome editing toolbox, and provide insight into how these synthetic biology tools could facilitate aging research by establishing in vitro cell and in vivo animal models to dissect genetic and epigenetic mechanisms underlying aging and age-related diseases. We discuss recent developments in the field with the aims to precisely modulate gene expression and dynamic epigenetic landscapes in a spatial and temporal manner in cellular and animal models, by complementing the CRISPR-based editing capability with conditional genetic manipulation tools including chemically inducible expression systems, optogenetics, logic gate genetic circuits, tissue-specific promoters, and the serotype-specific adeno-associated virus. We also discuss how the combined use of genome and epigenome editing tools permits investigators to uncover novel molecular pathways involved in the pathophysiology and etiology conferred by risk variants associated with aging and aging-related disease. A better understanding of the genetic and epigenetic regulatory mechanisms underlying human aging and age-related disease will significantly contribute to the developments of new therapeutic interventions for extending health span and life span, ultimately improving the quality of life in the elderly populations.


2021 ◽  
Author(s):  
Keya Li ◽  
Guiying Shi ◽  
Xuepei Lei ◽  
Yiying Huang ◽  
Xinyue Li ◽  
...  

Abstract Background and ObjectivesAdipose-tissue derived stem cells (ADSCs) autologous transplantation have been a promising strategy for aging-related disorder. But the relationship between ADSCs senescence and organismal aging were still no consistent conclusions. Toward this end, we analyzed the senescence properties of ADSCs from different age donors to furthermore understand the differences of cells between young and senile donors and verify the influence of organismal aging on the proliferation and function of ADSCs in vitro, providing the theoretical basis for the clinical application of autologous ADSCs transplantation.Methods and ResultsWe detected the characteristics, function, gene expression, apoptosis, cell cycle, SA-β-gal staining, and transcription features of ADSCs from 1-month mice and 20-month mice. ADSCs from old donors had some senescence-associated changes with less ability to proliferation than ADSCs from 1-month mice. Differentiation ability, cell surface markers, and SA-β-Gal staining did not differ across donor age, while cells exhibit a more remarkable age-related changes through continuous passages. According to the results of transcriptome analysis, the CCL7-CCL2-CCR2 axis and Hippo signaling pathway would be considered as its possible mechanisms. ConclusionsOur study reveals that ADSCs from old donors have some age-related alterations. The CCL7-CCL2-CCR2 which lies behind this change would be a potential target for gene therapy to reduce harmful effects of ADSCs from old donors. To make autologous transplantation work better, we would recommend that ADSCs should be cryopreserved in youth with minimum number of passages.


Author(s):  
Valeria Chiono

Since its adhesion to Centro3R, Politecnico di Torino has approached 3R teaching through a new Master course, entitled “New advances in alternative preclinical trials”. This is a multidisciplinary optional course for Master students in Biomedical Engineering, with the contribution of different teachers, who are experts on different aspects of preclinical testing of biomedical devices: European Standards for preclinical experimentation; preclinical animal models; protection of animal welfare in the European legislation; the role of statistics on the application of the 3R principle; preclinical experimental models in vitro; in silico models. This contribution describes the subjects faced by the course and their importance in the context of the 3R Principle.


2020 ◽  
Vol 21 (13) ◽  
pp. 4627
Author(s):  
Olivia Rastoin ◽  
Gilles Pagès ◽  
Maeva Dufies

Neovascular age-related macular degeneration (vAMD), characterized by the neo-vascularization of the retro-foveolar choroid, leads to blindness within few years. This disease depends on angiogenesis mediated by the vascular endothelial growth factor A (VEGF) and to inflammation. The only available treatments consist of monthly intravitreal injections of antibodies directed against VEGF or VEGF/VEGFB/PlGF decoy receptors. Despite their relative efficacy, these drugs only delay progression to blindness and 30% of the patients are insensitive to these treatments. Hence, new therapeutic strategies are urgently needed. Experimental models of vAMD are essential to screen different innovative therapeutics. The currently used in vitro and in vivo models in ophthalmic translational research and their relevance are discussed in this review.


2019 ◽  
Vol 316 (2) ◽  
pp. E319-E332 ◽  
Author(s):  
Mercedes Clemente-Postigo ◽  
Wilfredo Oliva-Olivera ◽  
Leticia Coin-Aragüez ◽  
Bruno Ramos-Molina ◽  
Rosa María Giraldez-Perez ◽  
...  

Impaired adipose tissue (AT) lipid handling and inflammation is associated with obesity-related metabolic diseases. Circulating lipopolysaccharides (LPSs) from gut microbiota (metabolic endotoxemia), proposed as a triggering factor for the low-grade inflammation in obesity, might also be responsible for AT dysfunction. Nevertheless, this hypothesis has not been explored in human obesity. To analyze the relationship between metabolic endotoxemia and AT markers for lipogenesis, lipid handling, and inflammation in human obesity, 33 patients with obesity scheduled for surgery were recruited and classified according to their LPS levels. Visceral and subcutaneous AT gene and protein expression were analyzed and adipocyte and AT in vitro assays performed. Subjects with obesity with a high degree of metabolic endotoxemia had lower expression of key genes for AT function and lipogenesis ( SREBP1, FABP4, FASN, and LEP) but higher expression of inflammatory genes in visceral and subcutaneous AT than subjects with low LPS levels. In vitro experiments corroborated that LPS are responsible for adipocyte and AT inflammation and downregulation of PPARG, SCD, FABP4, and LEP expression and LEP secretion. Thus, metabolic endotoxemia influences AT physiology in human obesity by decreasing the expression of factors involved in AT lipid handling and function as well as by increasing inflammation.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3596-3596
Author(s):  
Lilach Lifshitz ◽  
Galit Tabak ◽  
Max Gassman ◽  
Moshe Mittelman ◽  
Drorit Neumann

Abstract Abstract 3596 Poster Board III-533 The immunomodulatory effects of erythropoietin (EPO) on the cellular and humoral compartments of the immune system were originally described by our group in multiple myeloma patients and have been further elucidated in murine experimental models (Mittelman, 2001; Katz 2005; 2007; Prutchi-Sagiv, 2006). However, the mechanisms of action by which EPO affects lymphocyte number and function are still unknown, particularly since lymphocytes do not carry EPO receptors (EPO-R). We thus set to unravel mechanisms underlying the anti-neoplastic immunomodulatory action of EPO. These studies led us to the novel discovery that dendritic cells (DCs) express EPO-R, and that EPO enhances their survival and function (Prutchi-Sagiv, 2008; Lifshitz, 2009). Here we focus on macrophages as an additional EPO target, since in analogy to DCs, macrophages are also antigen presenting cells, and serve as key effectors of the innate immune response. Using murine models, we first explored the in-vivo effects of EPO using recombinant human EPO (rHuEPO, EPREXR, JC)-injected mice, as well as transgenic mice over-expressing human EPO (termed tg6). EPO treatment was associated with an increased splenic macrophage population, detected by F4/80 expression, and an increased number of macrophages expressing CD11b, CD80 and MHC class II. We further explored the effect of in-vivo EPO administration in an inflammatory model exploiting thioglygollate injection to induce recruitment of peritoneal inflammatory macrophages. The inflammatory macrophages obtained from both EPO injected and from tg6 mice displayed increased expression of F4/80, CD11b, CD80 and MHC class II and augmented phagocytic activity, as compared to the control counterparts. These results are supported by in-vitro studies in bone marrow derived macrophages (BMDMs). We show that BMDMs express EPO-R mRNA, as detected by RT-PCR. In-vitro stimulation of the BMDMs with rHuEPO activated multiple signaling pathways including STAT1, STAT5, MAPK, AKT and NFkB indicating macrophage activation via surface EPO-R. EPO treatment of the BMDMs up-regulated their surface expression of CD11b, F4/80 and CD80, as well as enhanced their phagocytic activity. EPO treatment of LPS-stimulated BMDMs augmented IL-12 secretion, and decreased IL-10 secretion. In conclusion our results show that macrophages are direct targets of EPO and that EPO treatment enhances their pro-inflammatory activity and function. These findings point to the multifunctional role of EPO and may advance its clinical applications as an anti-neoplastic immunomodulator. Disclosures: Mittelman: BioGAL- Start up (inactive): Equity Ownership, Patents & Royalties. Off Label Use: Non erythroid effects: immune, anti-cancer (all under investigation).


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