Epidemiology

Anusruti Neu GrDr. Ankita Anusruti - Epidemiology M.Sc.
Netzwerk AlternsfoRschung

Bergheimer Straße 20
69115 Heidelberg

Phone: +49 (0)6221 54 8143
anusruti(at)nar.uni-heidelberg.de

Fellow: Dr. Ben Schöttker, PhD

 

The risk and preventive factors for high serum levels of biomarkers of oxidative stress with a focus on obesity and type 2 diabetes

Summary of PhD thesis

The free radical theory of ageing, postulating that reactive oxygen species lead to accelerated aging, has drawn much attention since proposed by Denham Harman in 1956. Any imbalance between reactive oxygen species and antioxidants at a cellular level triggers oxidative stress, which may disrupt normal cell function due to damage to lipids, proteins, and DNA and hence, may impact negatively to cell senescence. Oxidative stress has an impact on periodontitis and both are correlated with modifiable lifestyle risk factors and metabolic diseases such as diabetes. A better management of periodontitis and oxidative stress could have an impact on healthy ageing.

In the first project, I elaborated on the relationships between weight measures and biomarkers for oxidative stress using an observational study. Derivatives of reactive oxygen metabolites and total thiol levels were measured in 1,734 participants of a population-based cohort study of older adults at two time points 3 years apart. Derivatives of reactive oxygen metabolites is a marker of lipid peroxidation while total thiol level is a marker of the antioxidant defense capacity. The longitudinal associations of BMI, waist-hip-ratio, and waist circumference with Derivatives of reactive oxygen metabolites and total thiol levels were assessed with multivariable-adjusted generalized linear models. The evaluation revealed that Derivatives of reactive oxygen metabolites levels were not significantly associated with any of the weight measures, i.e., were independent of the study participant’s weight. On the contrary, total thiol levels showed statistically significant, inversely linear associations with all weight measures meaning that a healthy body weight seems to be highly relevant for the anti-oxidative defense capacity of human beings. However, clinical trials are needed to corroborate if weight loss in obese individuals can effectively increase total thiol levels.

In the second project, I investigated potential factors associated with serum derivatives of reactive oxygen metabolites levels of type 2 diabetes mellitus (T2D patients by conducting cross-sectional and longitudinal analyses in two large cohorts and further strengthening these results by performing a meta-analysis. Serum derivatives of reactive oxygen metabolites concentrations were measured in a total of 2,146 type 2 diabetes mellitus patients from two independent cohort studies from Germany at baseline and again once more 3-4 years later. The relevant determinants of derivatives of reactive oxygen metabolites levels were identified with a backward selection algorithm.

In the meta-analysis of the cross-sectional analysis, the female sex, low education, obesity, smoking, high total cholesterol, C-reactive protein levels > 3 mg/L, HbA1c ≥ 7%, no diabetes medication, heart failure, and a history of myocardial infarction or cancer were statistically significantly associated with increased derivatives of reactive oxygen metabolites levels in type 2 diabetes mellitus patients. The meta-analysis of the longitudinal analysis revealed that an older age, the female sex, obesity, smoking, physical inactivity, high alcohol consumption, ≥ 5 years since diabetes diagnosis, and C-reactive protein levels between 3 and 10 mg/L were statistically significantly associated with derivatives of reactive oxygen metabolites levels measured 3-4 years later. This comprehensive analysis confirmed that several modifiable risk factors are being associated with oxidative stress in type 2 diabetes mellitus patients within an observational study design.

In summary, modifying lifestyle factors such as obesity, smoking, physical inactivity, and high alcohol consumption are likely to prevent high oxidative stress and decrease the severity of periodontitis in type 2 diabetes mellitus patients and other older adults. This could have a positive impact on healthy aging.

 

Publications

  • Anusruti A, Jansen EHJM, Gào X, Xuan X, Brenner H, Schöttker B. Longitudinal associations of body mass index, waist circumference and waist to hip ratio with biomarkers of oxidative stress in older adults: Results of a large cohort study. Obesity Facts. 2020;13(1):66-76.
  • Anusruti A, Xuan Y, Gào X, Jansen EHJM, Laetsch DC, Brenner H, Schöttker B. Factors associated with high oxidative stress in patients with type 2 diabetes: a meta-analysis of two cohort studies. BMJ Open Diabetes Res Care. 2020 Feb;8(1):e000933. doi: 10.1136/bmjdrc-2019-000933.

 

Vita

09/2016 - 08/2019   Member of Junior Research Group of Ben Schöttker, Network Ageing Research (NAR), Heidelberg University
09/2016 - 08/2019   PhD student, Division of Clinical Epidemiology and Ageing Research, German Cancer Research Center, Heidelberg
09/2015 - 08/2016     Masters of Epidemiology, Maastricht University, Maastricht, Netherlands
09/2013 - 09/2014   Master of Science in International Health, Institute of Public Health, Heidelberg University, Heidelberg, Germany
2005 - 2010   Bachelors of Dental Surgery (BDS), NTR University of Health Sciences, Andhra Pradesh, India
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Latest Revision: 2021-09-21
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