The Relationship Between Leukocyte Mitochondrial DNA Copy Number and Telomere Length in Community-Dwelling Elderly Women.

The Relationship between Leukocyte Mitochondrial DNA Copy Number and Telomere Length in Community-Dwelling Elderly Women.

PLoS One. 2013; 8(6): e67227
Kim JH, Kim HK, Ko JH, Bang H, Lee DC

Both telomere length and mitochondrial function are accepted as reflective indices of aging. Recent studies have shown that telomere dysfunction may influence impaired mitochondrial biogenesis and function. However, there has been no study regarding the possible association between telomere and mitochondrial function in humans. Therefore, the purpose of the study was to identify any relationships between mitochondrial and telomere function.The present study included 129 community-dwelling, elderly women. The leukocyte mitochondrial DNA copy number and telomere length were measured using a quantitative real-time polymerase chain reaction method. Anthropometric measurement, biochemical blood testing, a depression screening questionnaire using a 15-question geriatric depression scale (GDS-15), and a cognitive function test using the Korean version of the mini mental state examination (K-MMSE) were performed.Leukocyte mtDNA copy number was positively associated with telomere length (r=0.39, p=<0.0001) and K-MMSE score (r=0.06, p=0.02). Additionally, leukocyte mtDNA copy number was negatively correlated with GDS-15 score (r=-0.17, p=0.04). Age (r=-0.15, p=0.09), waist circumference (r=-0.16, p=0.07), and serum ferritin level (r=-0.13, p=0.07) tended to be inversely correlated with leukocyte mtDNA copy number. With a stepwise multiple regression analysis, telomere length was found to be an independent factor associated with leukocyte mtDNA copy number after adjustment for confounding variables including age, body mass index, waist circumference, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, hs-CRP, serum ferritin, HOMA-IR, K-MMSE, GDS-15, hypertension, diabetes, dyslipidemia, currently smoking, alcohol drinking, and regular exercise.This study showed that leukocyte mtDNA copy number was positively correlated with leukocyte telomere length in community-dwelling elderly women. Our findings suggest that telomere function may influence mitochondrial function in humans. HubMed – depression

 

Structural modeling and in silico analysis of human superoxide dismutase 2.

PLoS One. 2013; 8(6): e65558
de Carvalho MD, De Mesquita JF

Aging in the world population has increased every year. Superoxide dismutase 2 (Mn-SOD or SOD2) protects against oxidative stress, a main factor influencing cellular longevity. Polymorphisms in SOD2 have been associated with the development of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s disease, as well as psychiatric disorders, such as schizophrenia, depression and bipolar disorder. In this study, all of the described natural variants (S10I, A16V, E66V, G76R, I82T and R156W) of SOD2 were subjected to in silico analysis using eight different algorithms: SNPeffect, PolyPhen-2, PhD-SNP, PMUT, SIFT, SNAP, SNPs&GO and nsSNPAnalyzer. This analysis revealed disparate results for a few of the algorithms. The results showed that, from at least one algorithm, each amino acid substitution appears to harmfully affect the protein. Structural theoretical models were created for variants through comparative modelling performed using the MHOLline server (which includes MODELLER and PROCHECK) and ab initio modelling, using the I-Tasser server. The predicted models were evaluated using TM-align, and the results show that the models were constructed with high accuracy. The RMSD values of the modelled mutants indicated likely pathogenicity for all missense mutations. Structural phylogenetic analysis using ConSurf revealed that human SOD2 is highly conserved. As a result, a human-curated database was generated that enables biologists and clinicians to explore SOD2 nsSNPs, including predictions of their effects and visualisation of the alignment of both the wild-type and mutant structures. The database is freely available at http://bioinfogroup.com/database and will be regularly updated. HubMed – depression

 

Epidemiology of major depressive disorder in mainland china: a systematic review.

PLoS One. 2013; 8(6): e65356
Gu L, Xie J, Long J, Chen Q, Chen Q, Pan R, Yan Y, Wu G, Liang B, Tan J, Xie X, Wei B, Su L

Major depressive disorder (MDD) is one of the important causes of disease burden in the general population. Given the experiencing rapid economic and social changes since the early 1990s and the internationally recognized diagnostic criteria and interview instruments across the surveys during 2001-2010 in china, the epidemiological studies on MDD got varied results. We performed this meta-analysis to investigate current, 12-month and lifetime prevalence rates of MDD in mainland China.PubMed, Embase, Chinese Biological Medical Literature database (CBM), Chinese National Knowledge Infrastructure database (CNKI), and the Chinese Wanfang and Chongqing VIP database were searched for associated studies. We estimated the overall prevalence of MDD using meta-analysis.Seventeen eligible studies were included. Our study showed that the overall estimation of current, 12-month and lifetime prevalence of MDD was 1.6, 2.3, 3.3%, respectively. The current prevalence was 2.0 and 1.7% in rural and urban areas, respectively; between female and male, it was 2.1 and 1.3%, respectively. In addition, the current prevalence of MDD diagnosed with SCID (Structured Clinical Interview for DSM-IV) was 1.8% and that diagnosed with CIDI (Composite International Diagnostic Interview) was 1.1%. In conclusion, our study revealed a relatively high prevalence rate in the lifetime prevalence of MDD. For current prevalence, MDD diagnosed with SCID had a higher prevalence rate than with CIDI; males showed a lower rate than females, rural residents seemed to have a greater risk of MDD than urban residents. HubMed – depression

 

Decay of Impact after Self-Management Education for People with Chronic Illnesses: Changes in Anxiety and Depression over One Year.

PLoS One. 2013; 8(6): e65316
Park MJ, Green J, Ishikawa H, Yamazaki Y, Kitagawa A, Ono M, Yasukata F, Kiuchi T

In people with chronic illnesses, self-management education can reduce anxiety and depression. Those benefits, however, decay over time. Efforts have been made to prevent or minimize that “decay of impact”, but they have not been based on information about the decay’s characteristics, and they have failed. Here we show how the decay’s basic characteristics (prevalence, timing, and magnitude) can be quantified. Regarding anxiety and depression, we also report the prevalence, timing, and magnitude of the decay.Adults with various chronic conditions participated in a self-management educational program (n?=?369). Data were collected with the Hospital Anxiety and Depression Scale four times over one year. Using within-person effect sizes, we defined decay of impact as a decline of ?0.5 standard deviations after improvement by at least the same amount. We also interpret the results using previously-set criteria for non-cases, possible cases, and probable cases.Prevalence: On anxiety, decay occurred in 19% of the participants (70/369), and on depression it occurred in 24% (90/369). Timing: In about one third of those with decay, it began 3 months after the baseline measurement (6 weeks after the educational program ended). Magnitude: The median magnitudes of decay on anxiety and on depression were both 4 points, which was about 1 standard deviation. Early in the follow-up year, many participants with decay moved into less severe clinical categories (e.g., becoming non-cases). Later, many of them moved into more severe categories (e.g., becoming probable cases).Decay of impact can be identified and quantified from within-person effect sizes. This decay occurs in about one fifth or more of this program’s participants. It can start soon after the program ends, and it is large enough to be clinically important. These findings can be used to plan interventions aimed at preventing or minimizing the decay of impact. HubMed – depression