BACKGROUND: Leukocyte telomere length (LTL) shortening, a biomarker of telomere attrition, has been linked to multiple diseases. However, the relationship between LTL and digestive diseases remains uncertain. This study aimed to investigate the association between LTL and the risk of digestive diseases. METHODS: A cohort analysis of over 500,000 participants from the UK Biobank (UKB) between 2006 and 2021 was conducted to estimate the associations of LTL with more than 90 common digestive diseases. LTL was quantified using multiplex quantitative polymerase chain reaction, and cases of each disease were determined according to inpatient and primary care data. Multivariable Cox proportional hazards regression analysis was used to evaluate the associations of LTL with the risk of digestive diseases. Furthermore, such associations were also evaluated after stratification by sex and ethnicity. RESULTS: After a mean follow-up time of 11.8 years, over 20 International Classification of Diseases, 10th Revision ( ICD-10 ) codes were showed to be associated with telomere attrition. LTL shortening is associated with an increased risk of several digestive diseases, including gastroesophageal reflux disease (K21: hazard ratio [HR] = 1.30, 95% confidence interval [95% CI]: 1.19-1.42), esophageal ulcer (K221: HR = 1.81, 95% CI: 1.22-2.71), Barrett's esophagus (K227: HR = 1.58, 95% CI: 1.14-2.17), gastritis (K29: HR = 1.39, 95% CI: 1.26-1.52), duodenal ulcer (K26: HR = 1.55, 95% CI: 1.14-2.12), functional dyspepsia (K30X: HR = 1.36, 95% CI: 1.06-1.69), non-alcoholic fatty liver disease (NAFLD) (K760: HR = 1.39, 95% CI: 1.09-1.78), liver cirrhosis (K74: HR = 4.73, 95% CI: 3.27-6.85), cholangitis (K830: HR = 2.55, 95% CI: 1.30-5.00), and hernia (K43: HR = 1.50, 95% CI: 1.17-1.94; K44: HR = 1.29, 95% CI: 1.17-1.42). The risk of rectal polyps (K621: HR = 0.77, 95% CI: 0.63-0.92) decreased per unit shortening of LTL. CONCLUSIONS This study suggests that LTL shortening is associated with an increased risk of most digestive diseases except for rectal polyps. These findings may provide some clues for understanding the pathogenesis of digestive diseases.
Humans ; Male ; Female ; Middle Aged ; Cohort Studies ; Leukocytes/metabolism* ; Telomere/genetics* ; Proportional Hazards Models ; Adult ; Digestive System Diseases/genetics* ; Aged ; Risk Factors ; Telomere Shortening

OBJECTIVE: To explore the anti-photoaging properties of salvianolic acid B (Sal B). METHODS: The optimal photoaging model of human immortalized keratinocytes (HaCaT cells) were constructed by expose to ultraviolet B (UVB) radiation. The cells were divided into control, model and different concentrations of Sal B groups. Cell viability was measured via cell counting kit-8. Subsequently, the levels of oxidative stress, including reactive oxygen species (ROS), hydroxyproline (Hyp), catalase (CAT), and glutathione peroxidase (GSH-Px) were detected using the relevant kits. Silent information regulator 1 (SIRT1) protein level was detected using Western blot. The binding pattern of Sal B and SIRT1 was determined via molecular docking. RESULTS: Sal B significantly increased the viability of UVB-irradiated HaCaT cells (P<0.05 or P<0.01). Sal B effectively scavenged the accumulation of ROS induced by UVB (P<0.05 or P<0.01). In addition, Sal B modulated oxidative stress by increasing the intracellular concentrations of Hyp and CAT and the activity of GSH-Px (P<0.05 or P<0.01). The Western blot results revealed a substantial increase in SIRT1 protein levels following Sal B administration (P<0.05). Moreover, Sal B exhibited good binding affinity toward SIRT1, with a docking energy of -7.5 kCal/mol. CONCLUSION Sal B could improve the repair of photodamaged cells by alleviating cellular oxidative stress and regulating the expression of SIRT1 protein.
Humans ; Sirtuin 1/metabolism* ; Ultraviolet Rays ; Oxidative Stress/radiation effects* ; Keratinocytes/metabolism* ; Molecular Docking Simulation ; Benzofurans/pharmacology* ; Skin Aging/radiation effects* ; Reactive Oxygen Species/metabolism* ; Cell Survival/radiation effects* ; HaCaT Cells ; Hydroxyproline/metabolism* ; Glutathione Peroxidase/metabolism* ; Catalase/metabolism* ; Depsides

Oligodendrocyte lineage cells, including oligodendrocyte precursor cells (OPCs) and oligodendrocytes (OLs), are essential in establishing and maintaining brain circuits. Autophagy is a conserved process that keeps the quality of organelles and proteostasis. The role of autophagy in oligodendrocyte lineage cells remains unclear. The present study shows that autophagy is required to maintain the number of OPCs/OLs and myelin integrity during brain aging. Inactivation of autophagy in oligodendrocyte lineage cells increases the number of OPCs/OLs in the developing brain while exaggerating the loss of OPCs/OLs with brain aging. Inactivation of autophagy in oligodendrocyte lineage cells impairs the turnover of myelin basic protein (MBP). It causes MBP to accumulate in the cytoplasm as multimeric aggregates and fails to be incorporated into integral myelin, which is associated with attenuated endocytic recycling. Inactivation of autophagy in oligodendrocyte lineage cells impairs myelin integrity and causes demyelination. Thus, this study shows autophagy is required to maintain myelin quality during aging by controlling the turnover of myelin components.
Animals ; Autophagy/physiology* ; Oligodendroglia/metabolism* ; Myelin Sheath/physiology* ; Aging/pathology* ; Myelin Basic Protein/metabolism* ; Cell Lineage/physiology* ; Mice ; Oligodendrocyte Precursor Cells ; Mice, Inbred C57BL ; Brain/cytology* ; Cells, Cultured ; Cell Count

Mesenchymal stem cells (MSCs) are an effective therapeutic strategy to delay aging in dogs, they are prone to aging and have poor genetic stability when cultured for a long time in vitro. Therefore, it is of great significance to explore a method to improve the anti-aging ability of MSCs. Previous studies have shown that sirtuin 6 (SIRT6) plays an important role in anti-aging. This study constructed MSCs with overexpressed SIRT6 gene. Through Giemsa staining and senescence-associated β-galactosidase staining, it was found that SIRT6 significantly enhances the anti-aging capacity of MSCs. Transmission electron microscopy imaging and the detection of oxidative stress-related indicators revealed that SIRT6 improves the anti-aging capacity of MSCs by maintaining mitochondrial homeostasis and reducing oxidative stress levels. Transcriptome sequencing analysis revealed that SIRT6 mainly acted on phosphatidylinositol-3-kinase, mitogen-activated protein kinase and other aging and inflammation related pathways. In the establishment and verification of aging models in mice and dogs, it was found that the spatial memory ability of the model mice was significantly increased after intravenous transplantation of SIRT6 overexpression cells, the organ index was also significantly changed, and the anti-oxidative capacity of the dogs and mice blood was improved. The morphology of the spleens and livers in the SIRT6 overexpression cell treatment group could be effectively restored, and the expression levels of aging and inflammation-related proteins were significantly decreased. This study provides a new idea for the study of SIRT6-mediated anti-aging of MSCs.
Animals ; Dogs ; Mesenchymal Stem Cells/metabolism* ; Sirtuins/genetics* ; Aging/physiology* ; Mice ; Oxidative Stress ; Mesenchymal Stem Cell Transplantation

Cellular senescence, an irreversible state of cell cycle arrest characterized by phenotypic changes and a specific secretory profile, plays a dual role in liver health and disease. Under physiological conditions, senescence aids organ repair and regeneration, but its accumulation due to aging or pathological stress significantly contributes to chronic liver diseases, including alcoholic liver disease, metabolic dysfunction-associated steatohepatitis, liver fibrosis, and hepatocellular carcinoma. Senescence is identified by a range of cellular and molecular changes, such as morphological alterations, expression of cell cycle inhibitors, senescence-associated β-galactosidase activity, and nuclear membrane changes. The onset of senescence in organ cells can affect the entire organism, primarily through the senescence-associated secretory phenotype, which has autocrine, paracrine, and endocrine effects on tissue microenvironments. The objective of this review is to offer a contemporary overview of the pathophysiological events involving hepatic senescent cells and to elucidate their role in the onset and progression of liver diseases, particularly through mechanisms like telomere shortening, genomic and mitochondrial DNA damage, and inflammation. Additionally, this review discusses the emerging senolytic therapies aimed at targeting senescent cells to delay or mitigate liver disease progression. The therapeutic potential of these interventions, alongside their safety and effectiveness, highlights the need for further research to refine these approaches and address unresolved problems in the field of hepatic cellular senescence.
Humans ; Cellular Senescence/physiology* ; Liver Diseases ; Animals ; DNA Damage ; Telomere Shortening/physiology*

Recent studies have shown that the occurrence and development of common liver diseases, including non-alcoholic fatty liver disease, cirrhosis, and liver cancer, are related to liver aging(LA). Therefore, to explore the effect and mechanism of Dahuang Zhechong Pills(DHZCP), a traditional classic prescription in improving LA with multiple targets, the present study randomly divided 24 rats into a normal group, a model group, a DHZCP group, and a vitamin E(VE) group, with six rats in each group. The LA model was induced by continuous intraperitoneal injection of D-galactose(D-gal) in rats. For the LA model rats, the general situation was evaluated by aging phenotype and body weight(BW). LA was assessed by the pathological characteristics of hepatocyte senescence, hepatic function indexes, the staining characteristics of phosphorylated histone family 2A variant(γ-H2AX), and the expression levels of cell cycle arrest proteins(P21, P53, P16) and senescence-associated secretory phenotype(SASP) in the liver. The activation of the reactive oxygen species(ROS)-mediated phosphatidylinositol-3 kinase(PI3K)/protein kinase B(Akt)/forkhead box protein O4(FoxO4) signaling pathway was estimated by hepatic ROS expression feature and the protein expression levels of the key signaling molecules in the PI3K/Akt/FoxO4 signaling pathway. The results showed that after the treatment with DHZCP or VE for 12 weeks, for the DHZCP and VE groups, the characterized aging phenotype, BW, pathological characteristics of hepatocyte senescence, hepatic function indexes, relative expression of ROS in the liver, protein expression levels of key signaling molecules including p-PI3K, p-Akt, and FoxO4 in the liver, staining characteristics of γ-H2AX, and the protein expression levels of P16, P21, P53, interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α) in the liver were improved, and the effects of DHZCP and VE were similar. Based on the D-gal-induced LA model in rats, this study demonstrates that DHZCP can ameliorate LA with multiple targets in vivo, and its effects and mechanism are related to regulating the activation of the ROS-mediated PI3K/Akt/FoxO4 signaling pathway in the liver. These findings are expected to provide new pharmacological evidence for the treatment of DHZCP in aging-related liver diseases.
Animals ; Rats ; Proto-Oncogene Proteins c-akt/genetics* ; Phosphatidylinositol 3-Kinases/genetics* ; Reactive Oxygen Species ; Tumor Suppressor Protein p53/genetics* ; Signal Transduction ; Liver ; Aging ; Cell Cycle Proteins ; Interleukin-6

Chronological aging is the leading risk factor for human diseases, while aging at the cellular level, namely cellular senescence, is the fundamental driving force of organismal aging. The impact of cellular senescence on various life processes, including normal physiology, organismal aging and the progress of various age-related pathologies, has been largely ignored for a long time. However, with recent advancement in relevant fields, cellular senescence has become the core of aging biology and geriatric medicine. Although senescent cells play important roles in physiological processes including tissue repair, wound healing, and embryonic development, they can also contribute to tissue dysfunction, organ degeneration and various pathological conditions during adulthood. Senescent cells exert paracrine effects on neighboring cells in tissue microenvironments by developing a senescence-associated secretory phenotype, thus maintaining long-term and active intercellular communications that ultimately results in multiple pathophysiological effects. This is regarded as one of the most important discoveries in life science of this century. Notably, selective elimination of senescent cells through inducing their apoptosis or specifically inhibiting the senescence-associated secretory phenotype has shown remarkable potential in preclinical and clinical interventions of aging and age-related diseases. This reinforces the belief that senescent cells are the key drug target to alleviate various aging syndromes. However, senescent cells exhibit heterogeneity in terms of form, function and tissue distribution, and even differ among species, which presents a challenge for the translation of significant research achievements to clinical practice in future. This article reviews and discusses the characteristics of senescent cells, current targeting strategies and future trends, providing useful and valuable references for the rapidly blooming aging biology and geriatric medicine.
Humans ; Adult ; Aged ; Cellular Senescence/genetics* ; Aging ; Apoptosis ; Cell Communication ; Wound Healing/physiology*

Lamin B1 (LMNB1) is highly expressed in liver cancer tissues, and its influence and mechanism on the proliferation of hepatocellular carcinoma cells were explored by knocking down the expression of the protein. In liver cancer cells, siRNAs were used to knock down LMNB1. Knockdown effects were detected by Western blotting. Changes in telomerase activity were detected by telomeric repeat amplification protocol assay (TRAP) experiments. Telomere length changes were detected by quantitative real-time polymerase chain reaction (qPCR). CCK8, cloning formation, transwell and wound healing were performed to detect changes in its growth, invasion and migration capabilities. The lentiviral system was used to construct HepG2 cells that steadily knocked down LMNB1. Then the changes of telomere length and telomerase activity were detected, and the cell aging status was detected by SA-β-gal senescence staining. The effects of tumorigenesis were detected by nude mouse subcutaneous tumorigenesis experiments, subsequent histification staining of tumors, SA-β-gal senescence staining, fluorescence in situ hybridization (FISH) for telomere analysis and other experiments. Finally, the method of biogenesis analysis was used to find the expression of LMNB1 in clinical liver cancer tissues, and its relationship with clinical stages and patient survival. Knockdown of LMNB1 in HepG2 and Hep3B cells significantly reduced telomerase activity, cell proliferation, migration and invasion abilities. Experiments in cells and tumor formation in nude mice had demonstrated that stable knockdown of LMNB1 reduced telomerase activity, shortened telomere length, senesced cells, reduced cell tumorigenicity and KI-67 expression. Bioinformatics analysis showed that LMNB1 was highly expressed in liver cancer tissues and correlated with tumor stage and patient survival. In conclusion, LMNB1 is overexpressed in liver cancer cells, and it is expected to become an indicator for evaluating the clinical prognosis of liver cancer patients and a target for precise treatment.
Animals ; Mice ; Telomerase/metabolism* ; Carcinoma, Hepatocellular/genetics* ; Liver Neoplasms/genetics* ; Telomere Shortening ; In Situ Hybridization, Fluorescence ; Mice, Nude ; Telomere/pathology* ; Carcinogenesis

Cell aging is an extremely complex process, which is characterized by mitochondrial structural dysfunction, telomere shortening, inflammatory microenvironment, protein homeostasis imbalance, epigenetic changes, abnormal DNA damage and repair, etc. Aging is usually accompanied by structural and functional damage of tissues and organs which further induces the occurrence and development of aging-related diseases. Aging includes physiological aging caused by increased age and pathological aging induced by a variety of factors. Noteworthy, as a target organ directly contacting with the outside air, lung is more prone to various stimuli, causing pathological premature aging which is lung aging. Studies have found that there is a certain proportion of senescent cells in the lungs of most chronic respiratory diseases. However, the underlying mechanism by which these senescent cells induce lung senescence and their role in chronic respiratory diseases is still obscure. This paper focuses on the causes and classification of lung aging, the internal mechanism of lung aging involved in chronic respiratory diseases, and the application of anti-aging treatments in chronic respiratory diseases. We hope to provide new research ideas and theoretical basis for the clinical prevention and treatment in chronic respiratory diseases.
Aging/pathology* ; Cellular Senescence ; Humans ; Lung/pathology* ; Lung Diseases/pathology* ; Respiration Disorders/pathology* ; Telomere ; Telomere Shortening

Aging of craniofacial skeleton significantly impairs the repair and regeneration of trauma-induced bony defects, and complicates dental treatment outcomes. Age-related alveolar bone loss could be attributed to decreased progenitor pool through senescence, imbalance in bone metabolism and bone-fat ratio. Mesenchymal stem cells isolated from oral bones (OMSCs) have distinct lineage propensities and characteristics compared to MSCs from long bones, and are more suited for craniofacial regeneration. However, the effect of epigenetic modifications regulating OMSC differentiation and senescence in aging has not yet been investigated. In this study, we found that the histone demethylase KDM4B plays an essential role in regulating the osteogenesis of OMSCs and oral bone aging. Loss of KDM4B in OMSCs leads to inhibition of osteogenesis. Moreover, KDM4B loss promoted adipogenesis and OMSC senescence which further impairs bone-fat balance in the mandible. Together, our data suggest that KDM4B may underpin the molecular mechanisms of OMSC fate determination and alveolar bone homeostasis in skeletal aging, and present as a promising therapeutic target for addressing craniofacial skeletal defects associated with age-related deteriorations.
Aging ; Cell Differentiation ; Facial Bones/physiology* ; Humans ; Jumonji Domain-Containing Histone Demethylases/genetics* ; Mesenchymal Stem Cells/cytology* ; Osteogenesis ; Osteoporosis