Mild oxidative stress is beneficial for sperm telomere length maintenance

Increasing evidence from research on telomerase suggests that in addition to its catalytic telomere repeat synthesis activity, telomerase may have other biologically important functions. The canonical roles of telomerase are at the telomere ends where they elongate telomeres and maintain genomic stability and cellular lifespan. The catalytic protein component Telomerase Reverse Transcriptase (TERT) is preferentially expressed at high levels in cancer cells despite the existence of an alternative mechanism for telomere maintenance (alternative lengthening of telomeres or ALT). TERT is also expressed at higher levels than necessary for maintaining functional telomere length, suggesting other possible adaptive functions. Emerging non-canonical roles of TERT include regulation of non-telomeric DNA damage responses, promotion of cell growth and proliferation, acceleration of cell cycle kinetics, and control of mitochondrial integrity following oxidative stress. Non-canonical activities of TERT primarily show cellular protective effects, and nuclear TERT has been shown to protect against cell death following double-stranded DNA damage, independent of its role in telomere length maintenance. TERT has been suggested to act as a chromatin modulator and participate in the transcriptional regulation of gene expression. TERT has also been reported to regulate transcript levels through an RNA-dependent RNA Polymerase (RdRP) activity and produce siRNAs in a Dicer-dependent manner. At the mitochondria, TERT is suggested to protect against oxidative stress-induced mtDNA damage and promote mitochondrial integrity. These extra-telomeric functions of TERT may be advantageous in the context of increased proliferation and metabolic stress often found in rapidly-dividing cancer cells. Understanding the spectrum of non-canonical functions of telomerase may have important implications for the rational design of anti-cancer chemotherapeutic drugs.

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Telomere Length and Oxidative Stress and Its Relation with Metabolic Syndrome Components in the Aging

Biology ◽

10.3390/biology10040253 ◽

2021 ◽

Vol 10 (4) ◽

pp. 253

Author(s):

Graciela Gavia-García ◽

Juana Rosado-Pérez ◽

Taide Laurita Arista-Ugalde ◽

Itzen Aguiñiga-Sánchez ◽

Edelmiro Santiago-Osorio ◽

...

Keyword(s):

Oxidative Stress ◽

Metabolic Syndrome ◽

Telomere Length ◽

Scientific Evidence ◽

Telomeric Dna ◽

Biochemical Alterations ◽

The Metabolic Syndrome ◽

Age Related ◽

And Function

A great amount of scientific evidence supports that Oxidative Stress (OxS) can contribute to telomeric attrition and also plays an important role in the development of certain age-related diseases, among them the metabolic syndrome (MetS), which is characterised by clinical and biochemical alterations such as obesity, dyslipidaemia, arterial hypertension, hyperglycaemia, and insulin resistance, all of which are considered as risk factors for type 2 diabetes mellitus (T2DM) and cardiovascular diseases, which are associated in turn with an increase of OxS. In this sense, we review scientific evidence that supports the association between OxS with telomere length (TL) dynamics and the relationship with MetS components in aging. It was analysed whether each MetS component affects the telomere length separately or if they all affect it together. Likewise, this review provides a summary of the structure and function of telomeres and telomerase, the mechanisms of telomeric DNA repair, how telomere length may influence the fate of cells or be linked to inflammation and the development of age-related diseases, and finally, how the lifestyles can affect telomere length.

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Association of Metabolically Healthy and Unhealthy Obesity Phenotypes with Oxidative Stress Parameters and Telomere Length in Healthy Young Adult Men. Analysis of the MAGNETIC Study

Antioxidants ◽

10.3390/antiox10010093 ◽

2021 ◽

Vol 10 (1) ◽

pp. 93

Author(s):

Mateusz Lejawa ◽

Kamila Osadnik ◽

Tadeusz Osadnik ◽

Natalia Pawlas

Keyword(s):

Oxidative Stress ◽

Telomere Length ◽

Quantitative Polymerase Chain Reaction ◽

Oxidative Stress Markers ◽

Metabolic Disturbances ◽

Total Oxidation ◽

Stress Markers ◽

Metabolic Dysregulation ◽

Total Antioxidant ◽

Metabolically Healthy

Obesity is a significant factor related to metabolic disturbances that can lead to metabolic syndrome (MetS). Metabolic dysregulation causes oxidative stress, which affects telomere structure. The current study aimed to evaluate the relationships between telomere length, oxidative stress and the metabolically healthy and unhealthy phenotypes in healthy young men. Ninety-eight participants were included in the study (49 healthy slim and 49 obese patients). Study participants were divided into three subgroups according to body mass index and metabolic health. Selected oxidative stress markers were measured in serum. Relative telomere length (rTL) was measured using quantitative polymerase chain reaction. The analysis showed associations between laboratory markers, oxidative stress markers and rTL in metabolically healthy and unhealthy participants. Total oxidation status (TOS), total antioxidant capacity (TAC) and rTL were significantly connected with metabolically unhealthy obesity. TAC was associated with metabolically healthy obesity. Telomeres shorten in patients with metabolic dysregulation related to oxidative stress and obesity linked to MetS. Further studies among young metabolically healthy and unhealthy individuals are needed to determine the pathways related to metabolic disturbances that cause oxidative stress that leads to MetS.

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Telomere Shortening and Psychiatric Disorders: A Systematic Review

Cells ◽

10.3390/cells10061423 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1423

Author(s):

Pedro A. Pousa ◽

Raquel M. Souza ◽

Paulo Henrique M. Melo ◽

Bernardo H. M. Correa ◽

Tamires S. C. Mendonça ◽

...

Keyword(s):

Oxidative Stress ◽

Psychological Distress ◽

Mental Disorders ◽

Psychiatric Disorders ◽

Telomere Length ◽

Traumatic Stress ◽

Molecular Mechanisms ◽

Cochrane Library ◽

Telomere Shortening ◽

Anxiety Depression

Telomeres are aging biomarkers, as they shorten while cells undergo mitosis. The aim of this study was to evaluate whether psychiatric disorders marked by psychological distress lead to alterations to telomere length (TL), corroborating the hypothesis that mental disorders might have a deeper impact on our physiology and aging than it was previously thought. A systematic search of the literature using MeSH descriptors of psychological distress (“Traumatic Stress Disorder” or “Anxiety Disorder” or “depression”) and telomere length (“cellular senescence”, “oxidative stress” and “telomere”) was conducted on PubMed, Cochrane Library and ScienceDirect databases. A total of 56 studies (113,699 patients) measured the TL from individuals diagnosed with anxiety, depression and posttraumatic disorders and compared them with those from healthy subjects. Overall, TL negatively associates with distress-related mental disorders. The possible underlying molecular mechanisms that underly psychiatric diseases to telomere shortening include oxidative stress, inflammation and mitochondrial dysfunction linking. It is still unclear whether psychological distress is either a cause or a consequence of telomere shortening.

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Harsh conditions during early development influence telomere length in an altricial passerine: Links with oxidative stress and corticosteroids

Journal of Evolutionary Biology ◽

10.1111/jeb.13396 ◽

2018 ◽

Vol 32 (1) ◽

pp. 111-125 ◽

Cited By ~ 9

Author(s):

Diego Gil ◽

Sergio Alfonso-Iñiguez ◽

Lorenzo Pérez-Rodríguez ◽

Jaime Muriel ◽

Raquel Monclús

Keyword(s):

Oxidative Stress ◽

Telomere Length ◽

Early Development ◽

Harsh Conditions

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Oxidative Stress, Telomere Shortening, and Apoptosis Associated to Sarcopenia and Frailty in Patients with Multimorbidity

Journal of Clinical Medicine ◽

10.3390/jcm9082669 ◽

2020 ◽

Vol 9 (8) ◽

pp. 2669 ◽

Cited By ~ 2

Author(s):

Máximo Bernabeu-Wittel ◽

Raquel Gómez-Díaz ◽

Álvaro González-Molina ◽

Sofía Vidal-Serrano ◽

Jesús Díez-Manglano ◽

...

Keyword(s):

Oxidative Stress ◽

Telomere Length ◽

Prospective Observational Study ◽

Oxygen Species ◽

Oxidative Stress Markers ◽

Blood Leukocytes ◽

Telomere Shortening ◽

Blood Samples ◽

Stress Markers ◽

Total Antioxidant

Background: The presence of oxidative stress, telomere shortening, and apoptosis in polypathological patients (PP) with sarcopenia and frailty remains unknown. Methods: Multicentric prospective observational study in order to assess oxidative stress markers (catalase, glutathione reductase (GR), total antioxidant capacity to reactive oxygen species (TAC-ROS), and superoxide dismutase (SOD)), absolute telomere length (aTL), and apoptosis (DNA fragmentation) in peripheral blood samples of a hospital-based population of PP. Associations of these biomarkers to sarcopenia, frailty, functional status, and 12-month mortality were analyzed. Results: Of the 444 recruited patients, 97 (21.8%), 278 (62.6%), and 80 (18%) were sarcopenic, frail, or both, respectively. Oxidative stress markers (lower TAC-ROS and higher SOD) were significantly enhanced and aTL significantly shortened in patients with sarcopenia, frailty or both syndromes. No evidence of apoptosis was detected in blood leukocytes of any of the patients. Both oxidative stress markers (GR, p = 0.04) and telomere shortening (p = 0.001) were associated to death risk and to less survival days. Conclusions: Oxidative stress markers and telomere length were enhanced and shortened, respectively, in blood samples of polypathological patients with sarcopenia and/or frailty. Both were associated to decreased survival. They could be useful in the clinical practice to assess vulnerable populations with multimorbidity and of potential interest as therapeutic targets.

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The association of male infertility with telomere length: A case control study

Indian Journal of Clinical Anatomy and Physiology ◽

10.18231/j.ijcap.2021.070 ◽

2021 ◽

Vol 8 (4) ◽

pp. 325-332

Author(s):

Kate Deepali Rajesh ◽

Puranam Vatsalaswamy ◽

Manvikar Purshotam Rao

Keyword(s):

Male Infertility ◽

Telomere Length ◽

Real Time ◽

Real Time Pcr ◽

Case Control Study ◽

Case Control ◽

Control Group ◽

Significant Difference ◽

Control Study ◽

Sperm Telomere Length

To study the relevance of sperm telomere length and infertility in men. : Our case-control study included twenty-five males in couple with sub-fertility/infertility (test group) and twenty five healthy males (control group) with proven paternity in the age group 25 to 35 years. The Absolute Sperm Telomere length (aSTL) was measured by real-time PCR. We investigated whether any significant difference in the aSTL value existed between the groups and analysed the relationship between aSTL and other sperm parameters.The mean (SE) aSTL recorded in the infertile cases was significantly shorter than for the control group being 140.60 (6.66) Kb/genome and 239.63 (12.32) Kb/genome respectively (p <0.001) A weak correlation was eminent between aSTL kb/genome and the total sperm count mil/ml (rho= 0.04, p - 0.86), progressive sperm motility (rho= - 0.02, p=0.934) and sperm viability (rho= - 0.07 p=0.741) in the infertile group. The measurement of aSTL by real-time PCR is a simple and rapid method that offers further paramount information with respective to the quality of sperm. It is befitted for epidemiological studies, hence opening new perspectives in the evaluation of male infertility. Limitations - Our study was confined to men aged between 25 and 35 years. Further comparative studies are needed to explore the significance of STL and infertility in older males. Additional studies will help illumine the significance of aSTL as a prognostic biomarker in assisted reproduction.

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