Objective: To analyze the contribution and interaction of polycyclic aromatic hydrocarbons (PAH)-DNA adducts and changes of telomere length (TL) on missed abortion. Methods: From March to December 2019, patients with missed abortion in the First Hospital of Shanxi Medical University and pregnant women with normal pregnancy but voluntary abortion in the same department during the same period were selected and divided into a case group and a control group. Questionnaire was used to investigate the general situation and the pregnancy situation of the subjects. The abortion villi were collected and the content of PAH-DNA adducts and TL was detected. Logistic regression model was used to analyze the associated factors of missed abortion. R epiR package and Mediation package were used to analyze the effect and relationship between PAH-DNA adducts and TL on missed abortion. Results: The age of the subjects was(29.92±5.69)years old. The M(Q₁,Q₃)of PAH-DNA adducts was 453.75(404.61, 504.72) pg/ml. The M(Q₁,Q₃)of TL was 1.21(0.77, 1.72). The content of PAH-DNA adducts in the case group was higher than that in the control group (Z=-2.10, P=0.036), while the TL was lower than that in the control group (Z=-4.05, P<0.001). Multivariate logistic regression showed that low, medium and high levels of PAH-DNA adducts (OR=3.17,95%CI:1.41-7.14;OR=2.85,95%CI:1.25-6.52;OR=2.46,95%CI:1.07-5.64), and long, medium and short levels of TL (OR=2.50,95%CI:1.11-5.63;OR=3.32,95%CI:1.45-7.56;OR=3.22,95%CI:1.42-7.26) were all risk factors for missed abortion. The medium level of PAH-DNA adducts had a 2.76-fold higher risk of shortened TL than those with the lowest level, and no mediating role of TL was found. The stratified analysis showed that when the TL level was longer (>1.21), the low and high levels of PAH-DNA adducts were associated with missed abortion (all P<0.05); when the TL level was shorter (<1.21), the medium level of PAH-DNA adducts was associated with abortion (P=0.025). At lower levels of PAH-DNA adducts, no effect of TL on missed abortion was observed, while, at higher levels, TL was strongly associated with missed abortion (OR=7.50,95%CI:1.95-28.82;OR=6.04,95%CI:1.54-23.65;OR=9.05,95%CI:2.34-35.04). The interaction analysis found that the AP was 0.72 (95%CI: 0.46-0.99), and the SI was 5.21 (95%CI: 2.30-11.77). Conclusion: The high level of PAH-DNA adducts and shortened TL may increase the risk of missed abortion, and there may be a positive additive interaction between the two factors on missed abortion.
Humans ; Female ; Pregnancy ; Young Adult ; Adult ; DNA Adducts ; Abortion, Missed/chemically induced* ; Polycyclic Aromatic Hydrocarbons ; Abortion, Spontaneous/chemically induced* ; Telomere/chemistry*

As an important telomere binding protein, TPP1 protects the ends of telomeres and maintains the stability and integrity of its structure and function by interacting with other five essential core proteins (POT1, TRF1, TRF2, TIN2, and RAP1) to form a complex called Shelterin. Recently, researchers have discovered that TPP1 participates in protection of telomeres and regulation of telomerase activity. The relationship between TPP1 and tumorigenesis, tumor progression and treatment has also been investigated. This paper reviews the latest findings of TPP1 regarding to its structure, function and interaction with other proteins involved in tumorigenesis.
Chromosomal Instability ; DNA Damage ; Humans ; Neoplasms ; genetics ; Telomere ; Telomere-Binding Proteins ; chemistry ; physiology

The detection of sperm DNA damage, as an important supplement to semen routine examination strategies, has been applied in some clinical andrology laboratories. What factors may lead to sperm DNA damage remains one of the concerns among many andrologists. Present studies show a variety of factors of sperm DNA damage, including age, environmental pollutants such as organophosphorus and organochloride pesticides, plasticizer, heavy metals such as lead, carcinogens such as polycyclic aromatic hydrocarbons (c-PAHs) and zearalenone (ZEA), male reproductive system diseases or systemic diseases such as varicocele, infection, tumor, spermatogenesis and maturation dysfunction, spinal cord injury and endocrine disorders, seasons and temperature, lifestyle, abstinence time, semen refrigeration, semen handling in vitro, and certain medications. Among them, spermatogenesis and sperm maturation dysfunction may be the most secretive factors, which are involved in the molecular mechanisms of sperm chromatin packaging and restructuring, such as the transformation of histone to protamine, single nucleotide polymorphism of genes, and the role of telomere, which may be one of the hotspots in the future studies of sperm DNA damage. Relevant researches in the future are expected to focus on the prevention of sperm DNA damage and clarification of its specific pathogenic mechanisms so as to provide some evidence for its treatment.
Age Factors ; Chromatin ; chemistry ; DNA Damage ; Environmental Pollutants ; toxicity ; Humans ; Male ; Protamines ; Semen ; drug effects ; Specimen Handling ; Spermatogenesis ; Spermatozoa ; drug effects ; Telomere ; physiology ; Varicocele ; complications

Telomere assumes intra-molecular G-quadruplex that is a significant drug target for inhibiting telomerase maintenance of telomeres in cancer. Metal cations have been recognized as playing important roles in stabilizing G-quadruplex, but their binding processes to human telomeric G-quadruplex remain uncharacterized. To investigate the detailed binding procedures, molecular dynamics simulations were conducted on the hybrid [3 + 1] form-one human telomeric intra-molecular G-quadruplex. We show here that the binding of a potassium ion to a G-tetrad core is mediated by two alternative pathways. Principal component analysis illustrated the dominant concerted motions of G-quadruplex occurred at the loop domains. MM-PBSA calculations revealed that binding was energetically favorable and driven by the electrostatic interactions. The lower binding site was found more constructive favorable for binding. Our data provide useful information on a potassium-mediated stable structure of human telomeric intra-molecular G-quadruplex, implicating in ion disorder associated conformational changes and targeted drug design.
Binding Sites ; G-Quadruplexes ; Humans ; Molecular Dynamics Simulation ; Movement ; Potassium ; metabolism ; Principal Component Analysis ; Substrate Specificity ; Telomere ; chemistry ; metabolism ; Thermodynamics

OBJECTIVETo observe the effect of Angelica sinensis polysaccharides (ASP) on the length of telomere, the activity of telomerase and the expression of P53 protein in mice hematopoietic stem cells (HSCs), and explore ASP's potential mechanism for regulating HSC aging.

METHODC57BL/6J mice were randomly divided into the normal group, the aging group and the intervention group. The aging group was radiated with X ray to establish the mice aging HSC model. The intervention group was orally administered with ASP during X-ray irradiation, while the normal group was orally administered with NS. Their HSCs were isolated by immunomagnetic beads. Cell cycles analysis and senescence-associated beta-galactosidase (SA-beta-Gal) staining were used to detect changes in aging HSCs. The expression of P53 was determined by western blot analysis. The length of telomere and the vitality of telomerase were analyzed by southern blot and TRAP-PCR, respectively.

RESULTCompared with the normal group, X-ray irradiation could significantly increase the cell ratio of in HSC G1 stage, rate of SA-beta-Gal positive cells and expression of P53 protein, and reduce the length of telomere and the vitality of telomerase. Compared with the aging group, ASP could significantly inhibit the cell ratio of in HSC G1 stage and the increase in the number of SA-beta-Gal positive cells, down-regulate the expression of P53 protein, and increase the length of telomere and the vitality of telomerase in HSCs.

CONCLUSIONASP could antagonize X-ray-induced aging of HSCs, which may be related to the increase in the length of telomere and the activity of telomerase, as well as the down-regulation of the expression of P53 protein.

Angelica sinensis ; chemistry ; Animals ; Cell Cycle ; drug effects ; physiology ; Cellular Senescence ; drug effects ; physiology ; Female ; Hematopoietic Stem Cells ; cytology ; drug effects ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Plant Extracts ; chemistry ; pharmacology ; Plants, Medicinal ; chemistry ; Polysaccharides ; isolation & purification ; pharmacology ; Telomerase ; biosynthesis ; metabolism ; Telomere ; drug effects ; metabolism ; Tumor Suppressor Protein p53 ; biosynthesis ; metabolism

Alzheimer's disease (AD) is the most common cause of age-related dementia. The neuropathological hallmarks of AD include extracellular deposition of amyloid-beta peptides and neurofibrillary tangles that lead to intracellular hyperphosphorylated tau in the brain. Soluble amyloid-beta oligomers are the primary pathogenic factor leading to cognitive impairment in AD. Neural stem cells (NSCs) are able to self-renew and give rise to multiple neural cell lineages in both developing and adult central nervous systems. To explore the relationship between AD-related pathology and the behaviors of NSCs that enable neuroregeneration, a number of studies have used animal and in vitro models to investigate the role of amyloid-beta on NSCs derived from various brain regions at different developmental stages. However, the Abeta effects on NSCs remain poorly understood because of conflicting results. To investigate the effects of amyloid-beta oligomers on human NSCs, we established amyloid precursor protein Swedish mutant-expressing cells and identified cell-derived amyloid-beta oligomers in the culture media. Human NSCs were isolated from an aborted fetal telencephalon at 13 weeks of gestation and expanded in culture as neurospheres. Human NSCs exposure to cell-derived amyloid-beta oligomers decreased dividing potential resulting from senescence through telomere attrition, impaired neurogenesis and promoted gliogenesis, and attenuated mobility. These amyloid-beta oligomers modulated the proliferation, differentiation and migration patterns of human NSCs via a glycogen synthase kinase-3beta-mediated signaling pathway. These findings contribute to the development of human NSC-based therapy for AD by elucidating the effects of Abeta oligomers on human NSCs.
Amyloid beta-Peptides/*pharmacology ; Animals ; Apoptosis ; Cell Aging ; Cell Movement ; Cell Proliferation ; Culture Media, Conditioned/chemistry/pharmacology ; Fetus/cytology ; Glycogen Synthase Kinase 3/*metabolism ; HEK293 Cells ; Humans ; Mice ; Mice, Inbred C57BL ; Neural Stem Cells/*drug effects/metabolism/physiology ; Signal Transduction ; Telomere Shortening

Estrogen is implicated as playing an important role in aging and tumorigenesis of estrogen responsive tissues; however the mechanisms underlying the mitogenic actions of estrogen are not fully understood. Here we report that estrogen deficiency in mice caused by targeted disruption of the aromatase gene results in a significant inhibition of telomerase maintenance of telomeres in mouse ovaries in a tissue-specific manner. The inhibition entails a significant shortening of telomeres and compromised proliferation in the follicular granulosa cell compartment of ovary. Gene expression analysis showed decreased levels of proto-oncogene c-Myc and the telomerase catalytic subunit, telomerase reverse transcriptase (TERT), in response to estrogen deficiency. Estrogen replacement therapy led to increases in TERT gene expression, telomerase activity, telomere length and ovarian tissue growth, thereby reinstating ovary development to normal in four weeks. Our data demonstrate for the first time that telomere maintenance is the primary mechanism mediating the mitogenic effect of estrogen on ovarian granulosa cell proliferation by upregulating the genes of c-Myc and TERT in vivo. Estrogen deficiency or over-activity may cause ovarian tissue aging or tumorigenesis, respectively, through estrogen regulation of telomere remodeling.
46, XX Disorders of Sex Development ; drug therapy ; genetics ; metabolism ; Aging ; genetics ; metabolism ; Animals ; Aromatase ; deficiency ; genetics ; metabolism ; Cell Proliferation ; drug effects ; Estrogen Replacement Therapy ; Estrogens ; deficiency ; pharmacology ; Female ; Gene Expression ; Genes, myc ; genetics ; Granulosa Cells ; drug effects ; metabolism ; pathology ; Gynecomastia ; drug therapy ; genetics ; metabolism ; Humans ; Infertility, Male ; drug therapy ; genetics ; metabolism ; Metabolism, Inborn Errors ; drug therapy ; genetics ; metabolism ; Mice ; Mice, Knockout ; Telomerase ; genetics ; metabolism ; Telomere ; chemistry ; metabolism ; pathology

Distal 15q trisomy or tetrasomy is associated with a characteristic phenotype that includes mild to moderate intellectual disability, abnormal behavior, speech impairment, overgrowth, hyperlaxity, long face, prominent nose, puffy cheeks, pointed chin, small ears, and hand anomalies (mainly arachno- and camptodactyly). We present the case of a 13-yr-old girl with the main clinical features of 15q overgrowth syndrome and a 46,XX,dup(15)(q24q26.3)[117]/46,XX[3].ish dup(15)(q24q26.3) (SNPRN+,PML+,subtel++,tel++) de novo karyotype. The findings in this case are consistent with those in the previous distal 15q trisomy cases that presented with overgrowth and mental retardation. Further, the rearranged chromosome had a double set of directly oriented telomeric and subtelomeric sequences.
Adolescent ; *Chromosome Aberrations ; *Chromosomes, Human, Pair 15 ; Female ; Growth Disorders/diagnosis/*genetics ; Humans ; In Situ Hybridization, Fluorescence ; Mental Retardation/diagnosis/*genetics ; Syndrome ; Telomere/*chemistry

This study was aimed to explore the prognostic significance of telomere length in patients with chronic lymphocytic leukemia (CLL) and to analyze relation of telomere length with Binet stage, IgVH mutation status, CD38, ZAP-70 expression as well as other clinical features. 35 CLL patients who contained 80% or more tumor cells in the peripheral blood or bone marrow samples were selected as objects studied, while 13 healthy donors were served as normal controls. The telomere relative length was detected by using a real-time fluorescent quantitative polymerase chain reaction method (qPCR); the expression of CD38 and ZAP-70 protein were detected by flow cytometry, the IgVH mutation was detected by multiplex PCR. The results showed that the mean telomere relative length in CLL patients and normal controls were 0.384 and 0.443 respectively, but the difference between them was not significant (p > 0.05). The telomere length was significantly correlated with Binet stages and IgVH mutation status. Patients in Binet stage B and C showed significantly shorter telomeres than those in Binet stage A (p = 0.001). Mean telomere relative lengths in patients without IgVH mutation were shorter than those in patients with IgVH mutation (p = 0.015). No relation of telomere length with sex, age, ZAP-70 protein and CD38 were found (p > 0.05). It is concluded that telomere length may have a prognostic significance for CLL patients. Combining telomere length and IgVH mutation status may achieve a better prognostic subclassification for CLL patients.
ADP-ribosyl Cyclase 1 ; metabolism ; Adult ; Aged ; Aged, 80 and over ; Case-Control Studies ; Female ; Humans ; Leukemia, Lymphocytic, Chronic, B-Cell ; genetics ; metabolism ; Male ; Middle Aged ; Mutation ; Prognosis ; Telomere ; chemistry ; genetics ; metabolism ; ZAP-70 Protein-Tyrosine Kinase ; metabolism

OBJECTIVETo study the effects of Cynomorium songaricum polysaccharide (CSP) on telomere length in blood and brain tissues of aged mice in order to provide some evidence for CSP's development and applying in the clinical uses.

METHODKunming mice were intraperitoneal injected D-galactose (500 mg x kg(-1) x d(-1)) to make the aging models, and different dosages of CSP (20, 40, 80 mg x kg(-1)) were given by gavage for 56 days. The average length of telomere was determined by real-time fluorescence quantitative PCR.

RESULTThe relative T/S ratio of the group high and middle dosages of CSP in blood were 1.64 +/- 0.36 and 1.33 +/0.28, respectively, and higher than that of the group of senescence 1.01 +/- 0.13 (P < 0.01). Values of the group of high, middle, and low dosages of CSP in brain tissues were 3.34 +/- 0.58, 2.30 +/- 0. 75 and 1.55 +/- 0.58, respectively, and significantly higher than that of the group of senescence 1.04 +/- 0.33 (P < 0.01).

CONCLUSIONCSP can exert the anti-aging effects by increase telomere length f senescence mice.

Aging ; drug effects ; Animals ; Animals, Newborn ; Brain ; drug effects ; pathology ; Cellular Senescence ; drug effects ; Cynomorium ; chemistry ; Disease Models, Animal ; Drugs, Chinese Herbal ; therapeutic use ; Galactose ; pharmacology ; Humans ; In Situ Hybridization, Fluorescence ; Mice ; Polysaccharides ; pharmacology ; therapeutic use ; Telomere ; drug effects ; physiology