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PloS One 2023Parkinson's disease (PD) is the fastest-growing neurodegenerative disorder, currently affecting ~7 million people worldwide. PD is clinically and genetically...
Establishing an online resource to facilitate global collaboration and inclusion of underrepresented populations: Experience from the MJFF Global Genetic Parkinson's Disease Project.
Parkinson's disease (PD) is the fastest-growing neurodegenerative disorder, currently affecting ~7 million people worldwide. PD is clinically and genetically heterogeneous, with at least 10% of all cases explained by a monogenic cause or strong genetic risk factor. However, the vast majority of our present data on monogenic PD is based on the investigation of patients of European White ancestry, leaving a large knowledge gap on monogenic PD in underrepresented populations. Gene-targeted therapies are being developed at a fast pace and have started entering clinical trials. In light of these developments, building a global network of centers working on monogenic PD, fostering collaborative research, and establishing a clinical trial-ready cohort is imperative. Based on a systematic review of the English literature on monogenic PD and a successful team science approach, we have built up a network of 59 sites worldwide and have collected information on the availability of data, biomaterials, and facilities. To enable access to this resource and to foster collaboration across centers, as well as between academia and industry, we have developed an interactive map and online tool allowing for a quick overview of available resources, along with an option to filter for specific items of interest. This initiative is currently being merged with the Global Parkinson's Genetics Program (GP2), which will attract additional centers with a focus on underrepresented sites. This growing resource and tool will facilitate collaborative research and impact the development and testing of new therapies for monogenic and potentially for idiopathic PD patients.
Topics: Humans; Parkinson Disease; Palliative Care
PubMed: 37788254
DOI: 10.1371/journal.pone.0292180 -
Neurobiology of Disease Feb 2021Neurodegenerative disorders such as Alzheimer's disease (AD), Lewy body diseases (LBD), and the amyotrophic lateral sclerosis and frontotemporal dementia (ALS-FTD)... (Meta-Analysis)
Meta-Analysis
Neurodegenerative disorders such as Alzheimer's disease (AD), Lewy body diseases (LBD), and the amyotrophic lateral sclerosis and frontotemporal dementia (ALS-FTD) spectrum are defined by the accumulation of specific misfolded protein aggregates. However, the mechanisms by which each proteinopathy leads to neurodegeneration remain elusive. We hypothesized that there is a common "pan-neurodegenerative" gene expression signature driving pathophysiology across these clinically and pathologically diverse proteinopathies. To test this hypothesis, we performed a systematic review of human CNS transcriptomics datasets from AD, LBD, and ALS-FTD patients and age-matched controls in the Gene Expression Omnibus (GEO) and ArrayExpress databases, followed by consistent processing of each dataset, meta-analysis, pathway enrichment, and overlap analyses. After applying pre-specified eligibility criteria and stringent data pre-processing, a total of 2600 samples from 26 AD, 21 LBD, and 13 ALS-FTD datasets were included in the meta-analysis. The pan-neurodegenerative gene signature is characterized by an upregulation of innate immunity, cytoskeleton, and transcription and RNA processing genes, and a downregulation of the mitochondrial electron transport chain. Pathway enrichment analyses also revealed the upregulation of neuroinflammation (including Toll-like receptor, TNF, and NFκB signaling) and phagocytosis, and the downregulation of mitochondrial oxidative phosphorylation, lysosomal acidification, and ubiquitin-proteasome pathways. Our findings suggest that neuroinflammation and a failure in both neuronal energy metabolism and protein degradation systems are consistent features underlying neurodegenerative diseases, despite differences in the extent of neuronal loss and brain regions involved.
Topics: Alzheimer Disease; Amyotrophic Lateral Sclerosis; Brain; Energy Metabolism; Frontotemporal Dementia; Humans; Inflammation; Inflammation Mediators; Lewy Body Disease; Neurodegenerative Diseases; Proteostasis; Transcriptome
PubMed: 33347974
DOI: 10.1016/j.nbd.2020.105225 -
MSystems Dec 2020The spread of carbapenem- and polymyxin-resistant poses a significant threat to public health, challenging clinicians worldwide with limited therapeutic options. This... (Review)
Review
The spread of carbapenem- and polymyxin-resistant poses a significant threat to public health, challenging clinicians worldwide with limited therapeutic options. This review describes the current coding and noncoding genetic and transcriptional mechanisms mediating carbapenem and polymyxin resistance, respectively. A systematic review of all studies published in PubMed database between 2015 to October 2020 was performed. Journal articles evaluating carbapenem and polymyxin resistance mechanisms, respectively, were included. The search identified 171 journal articles for inclusion. Different New Delhi metallo-β-lactamase (NDM) carbapenemase variants had different transcriptional and affinity responses to different carbapenems. Mutations within the carbapenemase (KPC) mobile transposon, Tn, affect its promoter activity and expression levels, increasing carbapenem resistance. Insertion of IS in increased imipenemase expression 53-fold. porin downregulation (mediated by and mutations), small RNA hyperexpression, efflux upregulation (mediated by , , , , , , etc.), and mutations in - mediated clinical carbapenem resistance when coupled with β-lactamase activity in a species-specific manner but not when acting without β-lactamases. Mutations in , , , and affect phosphorylation of lipid A of the lipopolysaccharide through the ( or ) cluster, leading to polymyxin resistance; inactivation also affected capsule structure. Mobile and induced , efflux hyperexpression and porin downregulation, and Ecr transmembrane protein also conferred polymyxin resistance and heteroresistance. Carbapenem and polymyxin resistance is thus mediated by a diverse range of genetic and transcriptional mechanisms that are easily activated in an inducing environment. The molecular understanding of these emerging mechanisms can aid in developing new therapeutics for multidrug-resistant isolates.
PubMed: 33323413
DOI: 10.1128/mSystems.00783-20 -
Alzheimer's Research & Therapy Apr 2024Measurement of beta-amyloid (Aβ) and phosphorylated tau (p-tau) levels offers the potential for early detection of neurocognitive impairment. Still, the probability of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Measurement of beta-amyloid (Aβ) and phosphorylated tau (p-tau) levels offers the potential for early detection of neurocognitive impairment. Still, the probability of developing a clinical syndrome in the presence of these protein changes (A+ and T+) remains unclear. By performing a systematic review and meta-analysis, we investigated the risk of mild cognitive impairment (MCI) or dementia in the non-demented population with A+ and A- alone and in combination with T+ and T- as confirmed by PET or cerebrospinal fluid examination.
METHODS
A systematic search of prospective and retrospective studies investigating the association of Aβ and p-tau with cognitive decline was performed in three databases (MEDLINE via PubMed, EMBASE, and CENTRAL) on January 9, 2024. The risk of bias was assessed using the Cochrane QUIPS tool. Odds ratios (OR) and Hazard Ratios (HR) were pooled using a random-effects model. The effect of neurodegeneration was not studied due to its non-specific nature.
RESULTS
A total of 18,162 records were found, and at the end of the selection process, data from 36 cohorts were pooled (n= 7,793). Compared to the unexposed group, the odds ratio (OR) for conversion to dementia in A+ MCI patients was 5.18 [95% CI 3.93; 6.81]. In A+ CU subjects, the OR for conversion to MCI or dementia was 5.79 [95% CI 2.88; 11.64]. Cerebrospinal fluid Aβ42 or Aβ42/40 analysis and amyloid PET imaging showed consistent results. The OR for conversion in A+T+ MCI subjects (11.60 [95% CI 7.96; 16.91]) was significantly higher than in A+T- subjects (2.73 [95% CI 1.65; 4.52]). The OR for A-T+ MCI subjects was non-significant (1.47 [95% CI 0.55; 3.92]). CU subjects with A+T+ status had a significantly higher OR for conversion (13.46 [95% CI 3.69; 49.11]) than A+T- subjects (2.04 [95% CI 0.70; 5.97]). Meta-regression showed that the ORs for Aβ exposure decreased with age in MCI. (beta = -0.04 [95% CI -0.03 to -0.083]).
CONCLUSIONS
Identifying Aβ-positive individuals, irrespective of the measurement technique employed (CSF or PET), enables the detection of the most at-risk population before disease onset, or at least at a mild stage. The inclusion of tau status in addition to Aβ, especially in A+T+ cases, further refines the risk assessment. Notably, the higher odds ratio associated with Aβ decreases with age.
TRIAL REGISTRATION
The study was registered in PROSPERO (ID: CRD42021288100).
Topics: Humans; Prospective Studies; Retrospective Studies; Amyloidogenic Proteins; Cognitive Dysfunction; Dementia
PubMed: 38610055
DOI: 10.1186/s13195-024-01455-2 -
Cancers May 2020Several immunotherapy agents are the standard of care of many solid malignancies. Nevertheless, the majority of patients do not benefit from the currently available... (Review)
Review
Several immunotherapy agents are the standard of care of many solid malignancies. Nevertheless, the majority of patients do not benefit from the currently available immunotherapies. It is therefore of paramount importance to identify the prognostic and predictive factors of tumor response/resistance and to design effective therapeutic strategies to overcome primary resistance and improve the efficacy of immunotherapy. The aim of this review is to underline the influence of the tumor and host metabolism on the antitumor immune response and to discuss possible strategies to improve the efficacy of available treatments by targeting the specific metabolic pathways in tumors or immune cells and by modifying patients' nutritional statuses. A systematic search of the Medline and EMBASE databases was carried out to identify scientific papers published until February 2020, which reported original research articles on the influence of tumor or host metabolism on antitumor immune response. The literature data showed the key role of glycolysis and mitochondrial oxidative phosphorylation, arginine, tryptophan, glutamine, lipid metabolism and microbiome on immune cell function. Moreover, specific nutritional behaviors, such as a low dietary intake of vitamin C, low glycemic index and alpha-linolenic acid, eicosapentenoic acid, docosahexaenoic acid, ornithine ketoglutarate, tryptophan and probiotic supplementation were associated with the potential clinical benefits from the currently available immunotherapies.
PubMed: 32375310
DOI: 10.3390/cancers12051153 -
The Journal of Prevention of... 2024In patients with Alzheimer's disease pathophysiological changes of the brain that initiate the onset of Alzheimer's disease include accumulation of amyloid-β plaques... (Review)
Review
In patients with Alzheimer's disease pathophysiological changes of the brain that initiate the onset of Alzheimer's disease include accumulation of amyloid-β plaques and phosphorylation of tau-tangles. A rather recently considered risk factor for the onset of Alzheimer's disease is poor oral health. The aim of this systematic review of the literature was to assess the potential association(s) of oral health as a risk factor for the onset of Alzheimer's disease. After a systematic search of Pubmed, Embase and Web of Science. A total of 1962 studies were assessed, of which 17 studies demonstrated possible associations between oral health diseases and Alzheimer's disease. 4 theories could be distinguished that describe the possible links between oral health and the development or onset of Alzheimer's disease; 1) role of pathogens, 2) role of inflammatory mediators, 3) role of APOE alleles and 4) role of Aβ peptide. The main common denominator of all the theories is the neuroinflammation due to poor oral health. Yet, there is insufficient evidence to prove a link due to the diversity of the designs used and the quality of the study design of the included studies. Therefore, further research is needed to find causal links between oral health and neuroinflammation that possibly can lead to the onset of Alzheimer's disease with the future intention to prevent cognitive decline by better dental care.
Topics: Humans; Alzheimer Disease; Amyloid beta-Peptides; Neuroinflammatory Diseases; Oral Health; Risk Factors
PubMed: 38230738
DOI: 10.14283/jpad.2023.82 -
Cancers Aug 2020Fas-associated death domain (FADD) upregulation, i.e., gene amplification, protein phosphorylation and/or overexpression, has shown promising prognostic implications in... (Review)
Review
Fas-associated death domain (FADD) upregulation, i.e., gene amplification, protein phosphorylation and/or overexpression, has shown promising prognostic implications in head and neck squamous cell carcinoma (HNSCC). This systematic review and meta-analysis aims to evaluate the clinicopathological and prognostic significance of FADD upregulation in HNSCC. We searched studies published before February 2020 through PubMed, Embase, Web of Science, Scopus and Google Scholar. We evaluated the quality of the studies included using the QUIPS tool. The impact of FADD upregulation on survival and clinicopathological variables was meta-analysed. We explored heterogeneity and their sources, conducted sensitivity analyses and investigated small-study effects. Thirteen studies (1,923 patients) met inclusion criteria. FADD immunohistochemical overexpression was statistically associated with worse overall survival (hazard ratio [HR] = 1.52, 95% confidence intervals [CI] = 1.28-1.81, < 0.001), disease-specific survival (HR = 2.52, 95% CI = 1.61-3.96, < 0.001), disease-free survival (HR = 1.67, 95% CI=1.29-2.15, < 0.001), higher clinical stage (odds ratio [OR] = 1.72, 95% CI = 1.17-2.51, = 0.005) and a large magnitude of effect with N+ status (OR = 2.36, 95% CI = 1.85-3.00, < 0.001). FADD phosphorylation in ser-194 demonstrated no prognostic value, while no conclusive results can be drawn for FADD gene amplification. In conclusion, our findings indicate that immunohistochemical assessment of FADD overexpression could be incorporated into the prognostic evaluation of HNSCC.
PubMed: 32847023
DOI: 10.3390/cancers12092393 -
Oncotarget Aug 2017Oxidative stress results from an imbalance of the reactive oxygen species/reactive nitrogen species (ROS/RNS) production and the oxidants defense system. Extensive... (Review)
Review
Oxidative stress results from an imbalance of the reactive oxygen species/reactive nitrogen species (ROS/RNS) production and the oxidants defense system. Extensive research during the last decades has revealed that oxidative stress can mediate cancer initiation and development by leading not only to molecular damage but also to a disruption of reduction-oxidation (redox) signaling. In order to provide a global overview of the redox signaling pathways, which play a role in cancer formation, we conducted a systematic literature search in PubMed and ISI Web of Science and identified 185 relevant reviews published in the last 10 years. The 20 most frequently described pathways were selected to be presented in this systematic review and could be categorized into 3 groups: Intracellular ROS/RNS generating organelles and enzymes, signal transduction cascades kinases/phosphatases and transcription factors. Intracellular ROS/RNS generation organelles are mitochondria, endoplasmic reticulum and peroxisomes. Enzymes, including NOX, COX, LOX and NOS, are the most prominent enzymes generating ROS/RNS. ROS/RNS act as redox messengers of transmembrane receptors and trigger the activation or inhibition of signal transduction kinases/phosphatases, such as the family members of protein tyrosine kinases and protein tyrosine phosphatases. Furthermore, these reactions activate downstream signaling pathways including protein kinase of the MAPK cascade, PI3K and PKC. The kinases and phosphatases regulate the phosphorylation status of transcription factors including APE1/Ref-1, HIF-1α, AP-1, Nrf2, NF-κB, p53, FOXO, STAT, and β-catenin. Finally, we briefly discuss cancer prevention and treatment opportunities, which address redox pathways and further research needs.
PubMed: 28881698
DOI: 10.18632/oncotarget.17128 -
Journal of Alzheimer's Disease : JAD 2023The negative effects of periodontitis on systemic diseases, including diabetes, cardiovascular diseases, and Alzheimer's disease (AD), have been widely described.
BACKGROUND
The negative effects of periodontitis on systemic diseases, including diabetes, cardiovascular diseases, and Alzheimer's disease (AD), have been widely described.
OBJECTIVE
This systematic review aimed to gather the current understanding of the pathophysiological mechanisms linking periodontitis to AD.
METHODS
An electronic systematic search of the PubMed/MEDLINE, Scopus, and Embase databases was performed using the following PECO question: How can periodontitis or periodontal bacteria influence Alzheimer's disease features?". Only preclinical studies exploring the biological links between periodontitis and AD pathology were included. This study was registered at the International Prospective Register of Systematic Reviews (PROSPERO), and the Syrcle and Camarades protocols were used to assess the risk of bias.
RESULTS
After a systematic screening of titles and abstracts (n = 3,307), thirty-six titles were selected for abstract reading, of which 13 were excluded (k = 1), resulting in the inclusion of 23 articles. Oral or systemic exposure to periodontopathogens or their byproducts is responsible for both in situ brain manifestations and systemic effects. Significant elevated rates of cytokines and amyloid peptides (Aβ) and derivate products were found in both serum and brain. Additionally, in infected animals, hyperphosphorylation of tau protein, hippocampal microgliosis, and neuronal death were observed. Exposure to periodontal infection negatively impairs cognitive behavior, leading to memory decline.
CONCLUSIONS
Systemic inflammation and brain metastatic infections induced by periodontal pathogens contribute to neuroinflammation, amyloidosis, and tau phosphorylation, leading to brain damage and subsequent cognitive impairment.
Topics: Animals; Alzheimer Disease; Systematic Reviews as Topic; Periodontitis; Inflammation; Cognitive Dysfunction
PubMed: 37927257
DOI: 10.3233/JAD-230478 -
Mitochondrion Jul 2021Metabolic reprogramming and mitochondrial dysfunction are central elements in a broad variety of physiological and pathological processes. While cell culture established... (Review)
Review
Metabolic reprogramming and mitochondrial dysfunction are central elements in a broad variety of physiological and pathological processes. While cell culture established itself as a versatile technique for the elaboration of physiology and disease, studying metabolism using standard cell culture protocols is profoundly interfered by the Crabtree effect. This phenomenon refers to the adaptation of cultured cells to a glycolytic phenotype, away from oxidative phosphorylation in glucose-containing medium, and questions the applicability of cell culture in certain fields of research. In this systematic review we aim to provide a comprehensive overview and critical appraisal of strategies reported to circumvent the Crabtree effect.
Topics: Cell Culture Techniques; Culture Media; Glucose; Glycolysis; Humans; Mitochondria; Mitochondrial Dynamics; Oxidative Phosphorylation
PubMed: 33812964
DOI: 10.1016/j.mito.2021.03.014