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Gut microbial-derived phenylacetylglutamine accelerates host cellular senescence
Gut microbiota plays a crucial role in the host health in the aging process. However, the mechanisms for how gut microbiota triggers cellular senescence and the consequent impact on human aging remain enigmatic. Here we show that phenylacetylglutamine (PAGln), a metabolite linked to gut microbiota, drives host cellular senescence. Our findings indicate that the gut microbiota alters with age, which leads to increased production of phenylacetic acid (PAA) and its downstream metabolite PAGln in...
Effect of healthy lifestyle score trajectory on all-cause mortality in the late middle-aged and older population: Finding from 17-year retrospective cohort study
CONCLUSION: The findings of this study underscore the necessity of policies and institutional measures grounded in community networks to mitigate the risk of all-cause mortality among vulnerable groups with persistently poor HLST.
Host-microbe multiomic profiling identifies distinct COVID-19 immune dysregulation in solid organ transplant recipients
Coronavirus disease 2019 (COVID-19) poses significant risks for solid organ transplant recipients, who have atypical but poorly characterized immune responses to infection. We aim to understand the host immunologic and microbial features of COVID-19 in transplant recipients by leveraging a prospective multicenter cohort of 86 transplant recipients age- and sex-matched with 172 non-transplant controls. We find that transplant recipients have higher nasal SARS-CoV-2 viral abundance and impaired...
Identifying novel response markers for spinal muscular atrophy revealed by targeted proteomics following gene therapy
Spinal muscular atrophy (SMA) is a progressive disease that affects motor neurons, with symptoms usually starting in infancy or early childhood. Recent breakthroughs in treatments targeting SMA have improved both lifespan and quality of life for infants and children with the disease. Given the impact of these treatments, it is essential to develop methods for managing treatment-induced changes in disease characteristics. Zolgensma® is the first effective and approved gene therapy for SMA caused...
Amyloid-related imaging abnormalities: manifestations, metrics and mechanisms
Three monoclonal antibodies directed against specific forms of the amyloid-β (Aβ) peptide have been granted accelerated or traditional approval by the FDA as treatments for Alzheimer disease, representing the first step towards bringing disease-modifying treatments for this disease into clinical practice. Here, we review the detection, underlying pathophysiological mechanisms and clinical implications of amyloid-related imaging abnormalities (ARIA), the most impactful adverse effect of anti-Aβ...
Chromatin conformation, gene transcription, and nucleosome remodeling as an emergent system
In single cells, variably sized nanoscale chromatin structures are observed, but it is unknown whether these form a cohesive framework that regulates RNA transcription. Here, we demonstrate that the human genome is an emergent, self-assembling, reinforcement learning system. Conformationally defined heterogeneous, nanoscopic packing domains form by the interplay of transcription, nucleosome remodeling, and loop extrusion. We show that packing domains are not topologically associated domains....
Molecular basis for the stepwise and faithful maturation of the 20<em>S</em> proteasome
The proteasome degrades most superfluous and damaged proteins, and its decline is associated with many diseases. As the proteolytic unit, the 20S proteasome is assembled from 28 subunits assisted by chaperones PAC1/2/3/4 and POMP; then, it undergoes the maturation process, in which the proteolytic sites are activated and the assembly chaperones are cleared. However, mechanisms governing the maturation remain elusive. Here, we captured endogenous maturation intermediates of human 20S proteasome,...
Genesis and regulation of C-terminal cyclic imides from protein damage
C-Terminal cyclic imides are posttranslational modifications that can arise from spontaneous intramolecular cleavage of asparagine or glutamine residues resulting in a form of irreversible protein damage. These protein damage events are recognized and removed by the E3 ligase substrate adapter cereblon (CRBN), indicating that these aging-related modifications may require cellular quality control mechanisms to prevent deleterious effects. However, the factors that determine protein or peptide...
Social Connections, Leukocyte Telomere Length, and All-Cause Mortality in Older Adults From Costa Rica: The Costa Rican Longevity and Healthy Aging Study (CRELES)
OBJECTIVES: To examine the association of social connections with blood leukocyte telomere length (LTL) and all-cause mortality in older Costa Ricans.
Salidroside Improves Oocyte Competence of Reproductively Old Mice by Enhancing Mitophagy
The decline of oocyte quality with advanced maternal age has a detrimental effect on female fertility. However, there is limited knowledge of therapeutic options and their mechanisms to improve oocyte quality in reproductively older women. In this study, we demonstrated that supplementation of salidroside improves the oocyte quality of reproductively old mice. Salidroside improved the maturation, fertilization, and developmental competence of oocytes from reproductively old mice by maintaining...
Cellular Senescence Contributes to the Dysfunction of Tight Junctions in Submandibular Glands of Aging Mice
The current mechanism by which aging reduces salivary secretion is unknown. This study investigates the mechanism of aging-related submandibular (SMG) dysfunction and evaluates the therapeutic potential of dental pulp stem cell-derived exosomes (DPSC-exos). We found that the stimulated salivary flow rate was significantly reduced in naturally aging and D-galactose-induced aging mice (D-gal mice) compared to control mice. Acinar atrophy and periductal fibrosis in SMGs and parotid glands (PGs)...