Unraveling pathological mechanisms in neurological disorders: the impact of cell-based and organoid models

Systemic inflammation in Aβ1-40-induced Alzheimer's disease model: New translational opportunities

Alzheimer disease (AD) is the most frequent cause of dementia, and the most common neurodegenerative disease, which is characterized by memory impairment, neuronal death, and synaptic loss in the hippocampus. Sporadic late-onset AD, which accounts for over 95 % of disease cases, is a multifactorial pathology with complex etiology and pathogenesis. Nowadays, neuroinflammation is considered the third most important component of AD pathogenesis in addition to amyloid peptide generation and deposition. Neuroinflammation is associated with the impairment of blood-brain barrier and leakage of inflammatory mediators into the periphery with developing systemic inflammatory responses. Systemic inflammation is currently considered one of the therapeutic targets for AD treatment, that necessitates in-depth study of this phenomenon in appropriate non-transgenic animal models. This study was aimed to explore systemic inflammatory manifestations in rats with Aβ1-40-induced AD. The impairment of spatial memory and cognitive flexibility in Aβ1-40-lesioned rats was accompanied by pronounced systemic inflammation, which was confirmed by commonly accepted biomarkers: increased hematological indices of systemic inflammation (NLR, dNLR, LMR, PLR and SII), signs of anemia of inflammation or chronic diseases, and pro-inflammatory polarized activation of circulating phagocytes. In addition, markers of systemic inflammation strongly correlated with disorders of remote cognitive flexibility in Aβ1-40-lesioned rats. These results indicate, that Aβ1-40-induced AD model permits the investigation of specific element of the disease - systemic inflammation in addition to well reproduced neuroinflammation and impairment of spatial memory and cognitive flexibility. It increases translational value of this well-known model.

Bibliometric analysis of cerebral organoids and diseases in the last 10 years

Cerebral organoids have emerged as a powerful tool for mirroring the brain developmental processes and replicating its unique physiology. This bibliometric analysis aims to delineate the burgeoning trends in the application of cerebral organoids in disease research and offer insights for future investigations. We screened all relevant literature from the Web of Science on cerebral organoids in disease research during the period 2013-2022 and analyzed the research trends in the field using VOSviewer, CiteSpace, and Scimago Graphica software. According to the search strategy, 592 articles were screened out. The United States of America (USA) was the most productive, followed by China and Germany. The top nine institutions in terms of the number of publications include Canada and the United States, with the University of California, San Diego (USA), having the highest number of publications. The International Journal of Molecular Sciences was the most productive journal. Knoblich, Juergen A., and Lancaster, Madeline A. published the highest number of articles. Keyword cluster analysis showed that current research trends focused more on induced pluripotent stem cells to construct organoid models of cerebral diseases and the exploration of their mechanisms and therapeutic modalities. This study provides a comprehensive summary and analysis of global research trends in the field of cerebral organoids in diseases. In the past decade, the number of high-quality papers in this field has increased significantly, and cerebral organoids provide hope for simulating nervous system diseases (such as Alzheimer's disease).

Selecting the Best Animal Model of Parkinson's Disease for Your Research Purpose: Insight from in vivo PET Imaging Studies

Parkinson's disease (PD) is a debilitating neurodegenerative multisystem disorder leading to motor and non-motor symptoms in millions of individuals. Despite intense research, there is still no cure, and early disease biomarkers are lacking. Animal models of PD have been inspired by basic elements of its pathogenesis, such as dopamine dysfunction, alpha-synuclein accumulation, neuroinflammation and disruption of protein degradation, and these have been crucial for a deeper understanding of the mechanisms of pathology, the identification of biomarkers, and evaluation of novel therapies. Imaging biomarkers are non-invasive tools to assess disease progression and response to therapies; their discovery and validation have been an active field of translational research. Here, we highlight different considerations of animal models of PD that can be applied to future research, in terms of their suitability to answer different research questions. We provide the reader with important considerations of the best choice of model to use based on the disease features of each model, including issues related to different species. In addition, positron emission tomography studies conducted in PD animal models in the last 5 years are presented. With a variety of different species, interventions and genetic information, the choice of the most appropriate model to answer research questions can be daunting, especially since no single model recapitulates all aspects of this complex disorder. Appropriate animal models in conjunction with in vivo molecular imaging tools, if selected properly, can be a powerful combination for the assessment of novel therapies and developing tools for early diagnosis.

The Role of Neurotrophin Signaling in Age-Related Cognitive Decline and Cognitive Diseases

Neurotrophins are a family of secreted proteins expressed in the peripheral nervous system and the central nervous system that support neuronal survival, synaptic plasticity, and neurogenesis. Brain-derived neurotrophic factor (BDNF) and its high affinity receptor TrkB are highly expressed in the cortical and hippocampal areas and play an essential role in learning and memory. The decline of cognitive function with aging is a major risk factor for cognitive diseases such as Alzheimer’s disease. Therefore, an alteration of BDNF/TrkB signaling with aging and/or pathological conditions has been indicated as a potential mechanism of cognitive decline. In this review, we summarize the cellular function of neurotrophin signaling and review the current evidence indicating a pathological role of neurotrophin signaling, especially of BDNF/TrkB signaling, in the cognitive decline in aging and age-related cognitive diseases. We also review the therapeutic approach for cognitive decline by the upregulation of the endogenous BDNF/TrkB-system.