Low Magnesium in Conjunction with High Homocysteine and Less Sleep Accelerates Telomere Attrition in Healthy Elderly Australian

Low magnesium in conjunction with high homocysteine increases DNA damage in healthy middle aged Australians

PURPOSE

Magnesium is one of the most common elements in the human body and plays an important role as a cofactor of enzymes required for DNA replication and repair and many other biochemical mechanisms including sensing and regulating one-carbon metabolism deficiencies. Low intake of magnesium can increase the risk of many diseases, in particular, chronic degenerative disorders. However, its role in prevention of DNA damage has not been studied fully in humans so far. Therefore, we tested the hypothesis that magnesium deficiency either on its own or in conjunction with high homocysteine (Hcy) induces DNA damage in vivo in humans.

METHODS

The present study was carried out in 172 healthy middle aged subjects from South Australia. Blood levels of magnesium, Hcy, folate and vitamin B12 were measured. Cytokinesis-Block Micronucleus cytome assay was performed to measure three DNA damage biomarkers: micronuclei (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBuds) in peripheral blood lymphocytes.

RESULTS

Data showed that magnesium and Hcy are significantly inversely correlated with each other (r = - 0.299, p < 0.0001). Furthermore, magnesium is positively correlated both with folate (p = 0.002) and vitamin B12 (p = 0.007). Magnesium is also significantly inversely correlated with MN (p < 0.0001) and NPB (p < 0.0001). Individuals with low magnesium and high Hcy exhibited significantly higher frequency of MN and NPBs compared to those with high magnesium and low Hcy (p < 0.0001). Furthermore, there was an interactive effect between these two factors as well in inducing MN (p = 0.01) and NPB (p = 0.048).

CONCLUSIONS

The results obtained in the present study indicate for the first time that low in vivo levels of magnesium either on its own or in the presence of high Hcy increases DNA damage as evident by higher frequencies of MN and NPBs.

Reduced SIRT1 and SIRT3 and Lower Antioxidant Capacity of Seminal Plasma Is Associated with Shorter Sperm Telomere Length in Oligospermic Men

Infertility affects millions of couples worldwide and has a profound impact not only on their families, but also on communities. Telomere attrition has been associated with infertility, DNA damage and fragmentation. Oxidative stress has been shown to affect sperm DNA integrity and telomere length. Sirtuins such as SIRT1 and SIRT3 are involved in aging and oxidative stress response. The aim of the present study is to determine the role of SIRT1 and SIRT3 in regulating oxidative stress, telomere shortening, and their association with oligospermia. Therefore, we assessed the protein levels of SIRT1 and SIRT3, total antioxidant capacity (TAC), superoxide dismutase (SOD), malondialdehyde (MDA) and catalase activity (CAT) in the seminal plasma of 272 patients with oligospermia and 251 fertile men. We also measured sperm telomere length (STL) and leukocyte telomere length (LTL) using a standard real-time quantitative PCR assay. Sperm chromatin and protamine deficiency were also measured as per standard methods. Our results for oligospermic patients demonstrate significant reductions in semen parameters, shorter STL and LTL, lower levels of SOD, TAC, CAT, SIRT1 and SIRT3 levels, and also significant protamine deficiency and higher levels of MDA and DNA fragmentation. We conclude that a shorter TL in sperms and leukocytes is associated with increased oxidative stress that also accounts for high levels of DNA fragmentation in sperms. Our results support the hypothesis that various sperm parameters in the state of oligospermia are associated with or caused by reduced levels of SIRT1 and SIRT3 proteins.

Association of oxidative balance score with sleep quality: NHANES 2007-2014

BACKGROUND

Oxidative stress is correlated with sleep quality. A common tool for evaluating dietary and lifestyle exposures to oxidative stress is the Oxidative Balance Score (OBS), with higher OBS suggesting more substantial antioxidant exposures. The relationship between OBS and sleep quality is unclear. Investigating the association between OBS and sleep quality was the purpose of this study.

METHODS

To figure out the relationship between OBS and sleep quality, we utilized weighted linear models and weighted logistic regression. Adjusted models were also examined.

RESULTS

6300 participants who took part in the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2014 were recruited. OBS was negatively associated with sleep disorder (OR: 0.97; 95 % CI: 0.94-0.99), and positively associated with sleep duration (MD: 0.02; 95%CI: 0.01-0.03). Within the range of OBS > 24, each unit increase in OBS will result in a 40 % reduction in sleep disorder, and a 26 % increasement in sleep duration after adjustment (all P for trend <0.05). Dietary and lifestyle components were closely related to sleep quality independently. The relationship between OBS and sleep quality was prominent in the female population under 50 years of age. After stratification by education level, this relationship persisted.

LIMITATION

This research was cross-sectional design, and it was not possible to deduce causality.

CONCLUSION

Diet and lifestyle might influence sleep quality by modulating oxidative balance. Antioxidant diets and lifestyles were important in reducing sleep problems and our study also provided new ideas for improving sleep quality.

Mendelian randomization and colocalization analyses reveal an association between short sleep duration or morning chronotype and altered leukocyte telomere length

Observational studies suggest certain sleep traits are associated with telomere length, but the causal nature of these associations is unclear. The study aimed to determine the causal associations between 11 sleep-related traits and leukocyte telomere length (LTL) through two-sample Mendelian randomization and colocalization analyses using the summary statistics from large-scale genome-wide association studies. Univariable Mendelian randomization indicates that genetically determined short sleep is associated with decreased LTL, while morning chronotype is associated with increased LTL. Multivariable Mendelian randomization further supports the findings and colocalization analysis identifies shared common genetic variants for these two associations. No genetic evidence is observed for associations between other sleep-related traits and LTL. Sensitivity MR methods, reverse MR and re-running MR after removing potential pleiotropic genetic variants enhance the robustness of the results. These findings indicate that prioritizing morning chronotype and avoiding short sleep is beneficial for attenuating telomere attrition. Consequently, addressing sleep duration and chronotype could serve as practical intervention strategies.

The Relationship between Telomere Length and Nucleoplasmic Bridges and Severity of Disease in Prostate Cancer Patients

Telomeres are repetitive nucleotide (TTAGGG) sequences that stabilize the chromosome ends and play an important role in the prevention of cancer initiation and progression. Nucleoplasmic bridges (NPBs) are formed when chromatids remain joined together during mitotic anaphase either due to mis-repair of DNA breaks or due to chromatid end fusion as a result of telomere loss or telomere dysfunction. We tested the hypotheses that (i) telomere length (TL) is shorter in prostate cancer (PC) patients relative to healthy age-matched individuals, (ii) TL differs in different stages of PC and (iii) shorter TL is significantly correlated with NPBs formation in PC cases. TL was measured in whole blood by well-established quantitative PCR method and the frequency of NPBs was measured in lymphocytes using cytokinesis-block micronucleus cytome (CBMNcyt) assay. Our results indicate that TL is shorter and NPBs are increased in PC patients relative to age-matched healthy controls. Furthermore, TL was significantly shorter (p = 0.03) in patients with a Gleason score more than 7 and there was also a significant trend of decreasing TL across all three stages (p trend = 0.01; Gleason score <7, 7 and >7). Furthermore, TL was significantly inversely correlated with NPB frequency in PC patients (r = -0.316; p = 0.001) but not in controls (r = 0.163; p = 0.06) and their relationships became stronger with higher Gleason scores. More studies are required that can confirm our observations and explore mechanistic differences in the role of telomeres in NPB formation in PC cases relative to non-cancer cases.

Hypomagnesemia Is Associated with Excessive Daytime Sleepiness, but Not Insomnia, in Older Adults

The aim of this study was to investigate associations between serum magnesium levels with insomnia and excessive daytime sleepiness (EDS) in older adults. A total of 938 older outpatients were included in the study. Hypomagnesemia was defined as serum magnesium concentration below <1.6 mg/dL. Patients were divided into two groups: hypomagnesemia and normomagnesia (1.6-2.6 mg/dL). The Epworth Sleepiness Scale was implemented and scores of ≥11 points were categorized as EDS. The Insomnia Severity Index was implemented and scores of ≥8 indicated insomnia. The mean age was 81.1 ± 7.6 years. While the presence of EDS, hypertension, diabetes mellitus, and coronary artery disease were more common in the hypomagnesemia group than the normomagnesia group, Parkinson's disease was less common (p < 0.05). Hemoglobin and HDL cholesterol were lower, whereas HbA1c, triglyceride, and number of drugs used were higher in the hypomagnesemia group compared to the normomagnesia group (p < 0.05). In both univariate analysis and multivariate analysis adjusted for gender, age and all confounders, there were significant associations between hypomagnesemia and EDS [odds ratio (OR):1.7; 95% confidence interval (CI): 1.6-2.6, and OR: 1.9; 95%CI: 1.2-3.3, respectively (p < 0.05)]. There was no significant relationship between hypomagnesemia and insomnia (p > 0.05). The present study identified an association between hypomagnesemia and EDS in older adults. Therefore, it may be prudent to consider hypomagnesemia when evaluating older adults with EDS and vice versa.