Unraveling brain aging through the lens of oral microbiota

The oral cavity is a complex physiological community encompassing a wide range of microorganisms.Dysbiosis of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative diseases.Recent studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention strategies.In this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and neurodegeneration.We also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

Research on Performance Optimization of Spark Distributed Computing Platform

Spark,a distributed computing platform,has rapidly developed in the field of big data.Its in-memory computing feature reduces disk read overhead and shortens data processing time,making it have broad application prospects in large-scale computing applications such as machine learning and image processing.However,the performance of the Spark platform still needs to be improved.When a large number of tasks are processed simultaneously,Spark’s cache replacementmechanismcannot identify high-value data partitions,resulting inmemory resources not being fully utilized and affecting the performance of the Spark platform.To address the problem that Spark’s default cache replacement algorithm cannot accurately evaluate high-value data partitions,firstly the weight influence factors of data partitions are modeled and evaluated.Then,based on this weighted model,a cache replacement algorithm based on dynamic weighted data value is proposed,which takes into account hit rate and data difference.Better integration and usage strategies are implemented based on LRU(LeastRecentlyUsed).Theweight update algorithm updates the weight value when the data partition information changes,accurately measuring the importance of the partition in the current job;the cache removal algorithm clears partitions without useful values in the cache to releasememory resources;the weight replacement algorithm combines partition weights and partition information to replace RDD partitions when memory remaining space is insufficient.Finally,by setting up a Spark cluster environment,the algorithm proposed in this paper is experimentally verified.Experiments have shown that this algorithmcan effectively improve cache hit rate,enhance the performance of the platform,and reduce job execution time by 7.61%compared to existing improved algorithms.

Pancreas-specific Pten deficiency causes partial resistance to diabetes and elevated hepatic AKT signaling

PTEN, a negative regulator of the phosphatidylinositol-3-kinase/AKT pathway, is an important modulator of insulin signaling. To determine the metabolic function of pancreatic Pten, we generated pancreas-specific Pten knockout （PPKO） mice. PPKO mice had enlarged pancreas and elevated proliferation of acinar cells. They also exhibited hypoglycemia, hypoinsulinemia, and altered amino metabolism. Notably, PPKO mice showed delayed onset of streptozotocin （STZ）-induced diabetes and sex-biased resistance to high-fat-diet （HFD）-induced diabetes. To investigate the mechanism for the resistance to HFD-induced hyperglycemia in PPKO mice, we evaluated AKT phosphorylation in major insulin-responsive tissues： the liver, muscle, and fat. We found that Pten loss in the pancreas causes the elevation of AKT signaling in the liver. The phosphorylation of AKT and its downstream substrate GSK3β was increased in the liver of PPKO mice, while PTEN level was decreased without detectable excision of Pten allele in the liver of PPKO mice. Proteomics analysis revealed dramatically decreased level of 78-kDa glucose-regulated protein （GRP78） in the liver of PPKO mice, which may also contribute to the lower blood glucose level of PPKO mice fed with HFD. Together, our findings reveal a novel response in the liver to pancreatic defect in metabolic regulation, adding a new dimension to understanding diabetes resistance.

催化层掺杂共价有机框架材料提升高温聚电解质膜燃料电池性能

基于磷酸掺杂聚苯并咪唑(PBI)高温聚电解质膜燃料电池(HT-PEMFC)具有环境耐受性好、水热管理简单等优点,被认为是未来PEMFC的发展方向。而减少其运行过程中磷酸电解质的流失是维持HT-PEMFC性能稳定性的关键因素。在本工作中,我们提出在电极催化层中引入一种席夫碱型(SNW-1)共价有机框架(COF)材料的策略来减少膜电极(MEA)中的磷酸流失,从而增强HT-PEMFC的耐久性。由于该COF材料中大量与磷酸分子匹配的微孔和特定的官能团结构,使其不仅拥有优越的磷酸保留能力,而且具有良好的质子传导能力,因此该HT-PEMFC在电池加速老化测试中展现出很好的稳定性。此外,发现在催化层中引入5%–10%的COF材料,可有效提高电极电化学活性面积并降低电池的欧姆内阻和电荷转移电阻,从而可进一步提高HT-PEMFC放电性能。在150℃、氢/空和常压操作条件下,工作电压0.6 V时催化层中添加10%COF材料的电池电流密度达到0.361 A·cm^(−2),较常规电池性能提升30%左右。该工作说明在催化层中掺杂适量COF材料有希望成为提升HT-PEMFC性能和耐久性的一种有效策略。

The nutritional composition and digestion of plants foraged by red deer(Cervus elaphus xanthopygus) in northeast China

We studied species of plants foraged by red deer in the Muling forest region of northeastern China during January 2014 and 2015. We focused on nutritional composition, energy content, and the digestibility of these plants. Crude protein content varied by plant species.Average crude protein content was 7.5 ± 1.7% of dry matter, ranging from 4.5 to 10.3%. Crude lipid content did not vary by species and averaged 7 ± 1.5%(range5.4–9.8%). Non-fiber carbohydrate(NFC) and neutral detergent fiber(NDF) content varied broadly with average values being 20.1 ± 4.8%(range 13.5–28.8%) and64.7 ± 5.9%(range 53.5–71.8%), respectively. Energy content ranged from 16.7 to 19.7 k J/g. Average dry matter digestibility(DMD) was 46.1 ± 4.8%, with a range from38.7 to 54.6%. Only three plants, Saussurea manshurica,Aralia elata and Equisetum hyemale exhibited DMD [ 50%. NFC content explained most of the variation in energy content(r = 0.451). In contrast, energy content was inversely related to NDF(r =-0.443). There was no correlation between crude protein, crude lipid, and energy content(r= 0.004, r=-0.190). S. manshurica,A. elata and E. hyemale had higher NFC and lower NDF content. Thus, these species offered the greatest nutritional value for wintering red deer in the study area. Along with high CP and NFC content, Taxus cuspidate also had high lignin content, and was thus, considered a good forage species for red deer.

Research review on the main chemical constituents and pharmacological properties of Piper flaviflorum

Piper flaviflorum(P.flaviflorum),belonging to the Piper genus of Piperaceae family,is widely distributed in south-central Yunnan.As a traditional medicine,P.flaviflorum has been used by the Dai people to treat dysmenorrhea and tinea.Phytochemical investigations of P.flaviflorum have resulted in the isolation of alkaloids,essential oils,glycosides and organic acid.Studies have shown that chemical constituents of P.flaviflorum have various pharmacological activities including anti-inflammatory,antifungal and anti-tumor effects.This paper reviewed the chemical constituents and pharmacological activities of P.flaviflorum to provide practical and useful information for further research and development of this plant.

A single-nucleus transcriptomic atlas of primate liver aging uncovers the pro-senescence role of SREBP2 in hepatocytes

Aging increases the risk ofliver diseases and systemic susceptibility to aging-related diseases.However,cell type-specific changes and the underlying mechanism of liver aging in higher vertebrates remain incompletely characterized.Here,we constructed the first single-nucleus transcriptomic landscape of primate liver aging,in which we resolved cell type-specific gene expression fluctuation in hepatocytes across three liver zonations and detected aberrant cell-cell interactions between hepatocytes and niche cells.Upon in-depth dissection of this rich dataset,we identifed impaired lipid metabolism and upregulation of chronic inflammation-related genes prominently associated with declined liver functions during aging.In particular,hyperactivated sterol regulatory element-binding protein(SREBP)signaling was a hallmark of the aged liver,and consequently,forced activation of SREBP2 in human primary hepatocytes recapitulated in vivo aging phenotypes,manifesting as impaired detoxification and accelerated cellular senescence.This study expands our knowledge of primate liver aging and informs the development of diagnostics and therapeutic interventions for liver aging and associated diseases.

CRL2^(APPBP2)-mediated TSPYL2 degradation counteracts human mesenchymal stem cell senescence

Cullin-RING E3 ubiquitin ligases(CRLs),the largest family of multi-subunit E3 ubiquitin ligases in eukaryotic cells,represent core cellular machinery for executing protein degradation and maintaining proteostasis.Here,we asked what roles Cullin proteins play in human mesenchymal stem cell(hMSC)homeostasis and senescence.To this end,we conducted a comparative aging phenotype analysis by individually knocking down Cullin members in three senescence models:replicative senescent hMSCs,Hutchinson-Gilford Progeria Syndrome hMSCs,and Werner syndrome hMSCs.Among all family members,we found that CUL2 deficiency rendered hMSCs the most susceptible to senescence.To investigate CUL2-specific underlying mechanisms,we then applied CRISPR/Cas9-mediated gene editing technology to generate CUL2-deficient human embryonic stem cells(hESCs).When we differentiated these into h MSCs,we found that CUL2 deletion markedly accelerates hMSC senescence.Importantly,we identified that CUL2 targets and promotes ubiquitin proteasome-mediated degradation of TSPYL2(a known negative regulator of proliferation)through the substrate receptor protein APPBP2,which in turn downregulates one of the canonical aging marker-P21^(waf1/cip1),and thereby delays senescence.Our work provides important insights into how CRL2^(APPBP2)-mediated TSPYL2 degradation counteracts hMSC senescence,providing a molecular basis for directing intervention strategies against aging and aging-related diseases.

Single-nucleus transcriptomics uncovers a geroprotective role of YAP in primate gingival aging

Aging has a profound impact on the gingiva and significantly increases its susceptibility to periodontitis,a worldwide prevalent inflammatory disease.However,a systematic characterization and comprehensive understanding of the regulatory mechanism underlying gingival aging is still lacking.Here,we systematically dissected the phenotypic characteristics of gingiva during aging in primates and constructed the first single-nucleus transcriptomic landscape of gingival aging,by which a panel of cell type-specific signatures were elucidated.Epithelial cells were identified as the most affected cell types by aging in the gingiva.Further analyses pinpointed the crucial role of YAP in epithelial self-renew and homeostasis,which declined during aging in epithelial cells,especially in basal cells.The decline of YAP activity during aging was confrmed in the human gingival tissues,and downregulation of YAP in human primary gingival keratinocytes recapitulated the major phenotypic defects observed in the aged primate gingiva while overexpression of YAP showed rejuvenation effects.Our work provides an in-depth understanding of gingival aging and serves as a rich resource for developing novel strategies to combat aging-associated gingival diseases,with the ultimate goal of advancing periodontal health and promoting healthy aging.

DNA methylation clocks for estimating biological age in Chinese cohorts

Epigenetic clocks are accurate predictors of human chronological age based on the analysis of DNA methylation(DNAm)at specific CpG sites.However,a systematic comparison between DNA methylation data and other omics datasets has not yet been performed.Moreover,available DNAm age predictors are based on datasets with limited ethnic representation.To address these knowledge gaps,we generated and analyzed DNA methylation datasets from two independent Chinese cohorts,revealing age-related DNAm changes.Additionally,a DNA methylation aging clock(iCAS-DNAmAge)and a group of DNAm-based multi-modal clocks for Chinese individuals were developed,with most of them demonstrating strong predictive capabilities for chronological age.The clocks were further employed to predict factors influencing aging rates.The DNAm aging clock,derived from multi-modal aging features(compositeAge-DNAmAge),exhibited a close association with multi-omics changes,lifestyles,and disease status,underscoring its robust potential for precise biological age assessment.Our findings offer novel insights into the regulatory mechanism of age-related DNAm changes and extend the application of the DNAm clock for measuring biological age and aging pace,providing the basis for evaluating aging intervention strategies.

Aging hallmarks of the primate ovary revealed by spatiotemporal transcriptomics

The ovary is indispensable for female reproduction,and its age-dependent functional decline is the primary cause of infertility.However,the molecular basis of ovarian aging in higher vertebrates remains poorly understood.Herein,we apply spatiotemporal transcriptomics to benchmark architecture organization as well as cellular and molecular determinants in young primate ovaries and compare these to aged primate ovaries.From a global view,somatic cells within the non-follicle region undergo more pronounced transcriptional fluctuation relative to those in the follicle region,likely constituting a hostile microenvironment that facilitates ovarian aging.Further,we uncovered that inflammation,the senescent-associated secretory phenotype,senescence,and fibrosis are the likely primary contributors to ovarian aging(PCOA).Of note,we identified spatial co-localization between a PCOA-featured spot and an unappreciated MT2(Metallothionein 2)highly expressing spot(MT2^(high))characterized by high levels of inflammation,potentially serving as an aging hotspot in the primate ovary.Moreover,with advanced age,a subpopulation of MT2^(high)accumulates,likely disseminating and amplifying the senescent signal outward.Our study establishes the first primate spatiotemporal transcriptomic atlas,advancing our understanding of mechanistic determinants underpinning primate ovarian aging and unraveling potential biomarkers and therapeutic targets for aging and age-associated human ovarian disorders.

A Local Differential Privacy Trajectory Protection Method Based on Temporal and Spatial Restrictions for Staying Detection

The widespread availability of GPS has opened up a whole new market that provides a plethora of location-based services.Location-based social networks have become very popular as they provide end users like us with several such services utilizing GPS through our devices.However,when users utilize these services,they inevitably expose personal information such as their ID and sensitive location to the servers.Due to untrustworthy servers and malicious attackers with colossal background knowledge,users'personal information is at risk on these servers.Unfortunately,many privacy-preserving solutions for protecting trajectories have significantly decreased utility after deployment.We have come up with a new trajectory privacy protection solution that contraposes the area of interest for users.Firstly,Staying Points Detection Method based on Temporal-Spatial Restrictions(SPDM-TSR)is an interest area mining method based on temporal-spatial restrictions,which can clearly distinguish between staying and moving points.Additionally,our privacy protection mechanism focuses on the user's areas of interest rather than the entire trajectory.Furthermore,our proposed mechanism does not rely on third-party service providers and the attackers'background knowledge settings.We test our models on real datasets,and the results indicate that our proposed algorithm can provide a high standard privacy guarantee as well as data availability.

Human ESC-derived vascular cells promote vascular regeneration in a HIF-1α dependent manner

Hypoxia-inducible factor(HIF-1α),a core transcription factor responding to changes in cellular oxygen levels,is closely associated with a wide range of physiological and pathological conditions.However,its differential impacts on vascular cell types and molecular programs modulating human vascular homeostasis and regeneration remain largely elusive.Here,we applied CRISPR/Cas9-mediated gene editing of human embryonic stem cells and directed differentiation to generate HIF-ia-deficient human vascular cells including vascular endothelial cells,vascular smooth muscle cells,and mesenchymal stem cells(MsCs),as a platform for discovering cell type-specific hypox-ia-induced response mechanisms.Through comparative molecular profiling across cell types under normoxic and hypoxic conditions,we provide insight into the indispensable role of HIF-1αin the promotion of ischemic vascular regeneration.We found human MSCs to be the vascular cell type most susceptible to HIF-1a deficiency,and that transcriptional inactivation of ANKZF1,an effector of HIF-1a,impaired pro-angiogenic processes.Altogether,our findings deepen the understanding of HIF-ia in human angiogenesis and support further explorations of novel therapeutic strategies of vascular regeneration against ischemic damage.

Identification of FOXO1 as a geroprotector in human synovium through single-nucleus transcriptomic profiling

The synovium,a thin layer of tissue that is adjacent to the joints and secretes synovial fluid,undergoes changes in aging that contribute to intense shoulder pain and other joint diseases.However,the mechanism underlying human synovial aging remains poorly characterized.Here,we generated a comprehensive transcriptomic profile of synovial cells present in the subacromial synovium from young and aged individuals.By delineating aging-related transcriptomic changes across different cell types and their associated regulatory networks,we identified two subsets of mesenchymal stromal cells(MSCs)in human synovium,which are lining and sublining MSCs,and found that angiogenesis and fibrosis-associated genes were upregulated whereas genes associated with cell adhesion and cartilage development were downregulated in aged MSCs.Moreover,the specific cell-cell communications in aged synovium mirrors that of aging-related inflammation and tissue remodeling,including vascular hyperplasia and tissue fibrosis.In particular,we identified forkhead box O1(FOXO1)as one of the major regulons for aging differentially expressed genes(DEGs)in synovial MSCs,and validated its downregulation in both lining and sublining MSC populations of the aged synovium.In human FOXO1-depleted MSCs derived from human embryonic stem cells,we recapitulated the senescent phenotype observed in the subacromial synovium of aged donors.These data indicate an important role of FOXO1 in the regulation of human synovial aging.Overall,our study improves our understanding of synovial aging during joint degeneration,thereby informing the development of novel intervention strategies aimed at rejuvenating the aged joint.

Degeneration Directory:a multi-omics web resource for degenerative diseases

Background of database.Organ degeneration refers to the gradual decline in organ function and structure deterioration that occurs during aging,which represents the greatest risk factor for various degenerative diseases,including cardiovascular diseases,neurodegenerative diseases,and osteoarthritis,etc.(Aging Biomarker et al.,2023;Becker et al.,2018;Cai et al.,2022).

MAVS Antagonizes Human Stem Cell Senescence as a Mitochondrial Stabilizer

Mitochondrial dysfunction is a hallmark feature of cellular senescence and organ aging.Here,we asked whether the mitochondrial antiviral signaling protein(MAVS),which is essential for driving antiviral response,also regulates human stem cell senescence.To answer this question,we used CRISPR/Cas9-mediated gene editing and directed differentiation techniques to generate various MAVS-knockout human stem cell models.We found that human mesenchymal stem cells(hMSCs)were sensitive to MAVS deficiency,as manifested by accelerated senescence phenotypes.We uncovered that the role of MAVS in maintaining mitochondrial structural integrity and functional homeostasis depends on its interaction with the guanosine triphosphatase optic atrophy type 1(OPA1).Depletion of MAVS or OPA1 led to the dysfunction of mitochondria and cellular senescence,whereas replenishment of MAVS or OPA1 in MAVS-knockout hMSCs alleviated mitochondrial defects and premature senescence phenotypes.Taken together,our data underscore an uncanonical role of MAVS in safeguarding mitochondrial homeostasis and antagonizing human stem cell senescence.

Multimodal Omics Approaches to Aging and Age‑Related Diseases

Aging is associated with a progressive decline in physiological capacities and an increased risk of aging-associated disorders.An increasing body of experimental evidence shows that aging is a complex biological process coordinately regulated by multiple factors at diferent molecular layers.Thus,it is difcult to delineate the overall systematic aging changes based on single-layer data.Instead,multimodal omics approaches,in which data are acquired and analyzed using complementary omics technologies,such as genomics,transcriptomics,and epigenomics,are needed for gaining insights into the precise molecular regulatory mechanisms that trigger aging.In recent years,multimodal omics sequencing technologies that can reveal complex regulatory networks and specifc phenotypic changes have been developed and widely applied to decode aging and age-related diseases.This review summarizes the classifcation and progress of multimodal omics approaches,as well as the rapidly growing number of articles reporting on their application in the feld of aging research,and outlines new developments in the clinical treatment of age-related diseases based on omics technologies.

Chemical screen identifies a geroprotective role of quercetin in premature aging

Aging increases the risk of various diseases. The main goal of aging research is to find therapies that attenuate aging and alleviate aging-related diseases. In this study, we screened a natural product library for geroprotective compounds using Werner syndrome (WS) human mesenchymal stem cells (hMSCs), a premature aging model that we recently established. Ten candidate compounds were identified and quercetin was investigated in detail due to its leading effects. Mechanistic studies revealed that quercetin alleviated senescence via the enhancement of cell proliferation and restoration of heterochromatin architecture in WS hMSCs. RNA-sequencing analysis revealed the transcriptional commonalities and differences in the geroprotective effects by quercetin and Vitamin C. Besides WS hMSCs, quercetin also attenuated cellular senescence in Hutchinson-Gilford progeria syndrome (HGPS) and physiological-aging hMSCs. Taken together, our study identifies quercetin as a geroprotective agent against accelerated and natural aging in hMSCs, providing a potential therapeutic intervention for treating age-associated disorders.

SIRT7 antagonizes human stem cell aging as a heterochromatin stabilizer

SIRT7,a sirtuin family member implicated in aging and disease,is a regulator of metabolism and stress responses.It remains elusive how human somatic stem cell populations might be impacted by SIRT7.Here,we found that SIRT7 expression declines during human mesenchymal stem cell(hMSC)aging and that SIRT7 deficiency accelerates senescence.Mechanistically,SIRT7 forms a complex with nuclear lamina proteins and heterochromatin proteins,thus maintaining the repressive state of heterochromatin at nuclear periphery.Accordingly,deficiency of SIRT7 results in loss of heterochromatin,derepression of the LINE1 retrotransposon(LINE1),and activation of innate immune signaling via the cGAS-STING pathway.These agingassociated cellular defects were reversed by overexpression of heterochromatin proteins or treatment with a LINE1 targeted reverse-transcriptase inhibitor.Together,these findings highlight how SIRT7 safeguards chromatin architecture to control innate immune regulation and ensure geroprotection during stem cell aging.

Differential stem cell aging kinetics in Hutchinson-Gilford progeria syndrome and Werner syndrome

progeria syndrome （HGPS） and Wemer syndrome （WS） are two of the best characterized human progeroid syndromes. HGPS is caused by a point mutation in lamin A （LMNA） gene, resulting in the production of a truncated protein product-progerin. WS is caused by mutations in 14/RN gem）, encoding a loss-of-function RecQ DNA helicase. Here, by gene editing we created isogenic human embryonic stem cells （ESCs） with heterozygous （G608G/＋） or homozygous （G608G/G608G） LMNA mutation and biallelic WRN knockout, for modeling HGPS and WS pathogenesis, respectively. While ESCs and endothelial cells （ECs） did not present any features of premature senescence, HGPS- and WS-mesenchymal stem cells （MSCs） showed aging-associated phenotypes with different kinetics. WS-MSCs had early-onset mild premature aging phenotypes while HGPS-MSCs exhibited iate-onset acute premature aging characterisitcs. Taken together, our study compares and contrasts the distinct pathologies underpinning the two premature aging disorders, and provides reliable stem-cell based models to identify new therapeutic strategies for pathological and physiological aging.