Chanachai Sae-Lee

Bio: Chanachai Sae-Lee is an academic researcher from Newcastle University. The author has contributed to research in topics: DNA methylation & Epigenetics. The author has an hindex of 4, co-authored 4 publications receiving 52 citations. Previous affiliations of Chanachai Sae-Lee include Mahidol University.

Dietary intervention modifies DNA methylation age assessed by the epigenetic clock

Abstract: Scope: Alterations in DNA methylation patterns are correlated with aging, environmental exposures and disease pathophysiology; the possibility of reverting or preventing these processes through dietary intervention is gaining momentum. In particular, methyl donors that provide S-adenosyl-methionine for one-carbon metabolism and polyphenols such as flavanols that inhibit the activity of DNA methyltransferases (DNMTs) could be key modifiers of epigenetic patterns. Methods and results: We assessed DNA methylation patterns in publicly available Illumina Infinium 450K methylation datasets from intervention studies with either folic acid + vitamin B12 (GSE74548) or monomeric and oligomeric flavanols (MOF) (GSE54690) in 44 and 13 participants, respectively. Global DNA methylation levels increased in unmethylated regions such as CpG islands and shores following folic acid + vitamin B12 supplementation and decreased in highly methylated regions, including shelves and open-seas following intervention with MOF. After supplementation with folic acid + vitamin B12, epigenetic age, estimated by the Horvath ‘epigenetic clock’ model, was reduced in women with the MTHFR 677CC genotype. Conclusions: The effects of supplementation with folic acid + vitamin B12 and MOF on DNA methylation age are dependent upon gender and MTHFR genotype. Additionally, our findings demonstrate the potential for these dietary factors to modulate global DNA methylation profiles.

Psychosocial stress is associated with benign breast disease in young Chinese women: results from Project ELEFANT

Abstract: Psychosocial stress, including bereavement and work-related stress, is associated with the risk of breast cancer. However, it is unknown whether it may also be linked with increased risk of benign breast disease (BBD). Our study leveraged 61,907 women aged 17–55 years old from the Project ELEFANT study. BBD was diagnosed by clinician. Self-reported data on psychosocial stress over a 10-year period was retrospectively collected from questionnaires and categorised by cause (work, social and economic) and severity (none, low and high). Odd ratios (ORs) for the development of BBD were estimated using logistic regression. The model was adjusted for age, BMI, TSH levels, smoking, alcohol consumption, family history, age of menarche, oral contraceptive usage, education and occupation. Within our study, 8% (4,914) of participants were diagnosed with BBD. Work-related stress [OR 1.57, 95% confidence interval (CI) 1.46–1.69] and financial stress (OR 1.34, 95% CI 1.24–1.44) were significantly associated with BBD incidence, with a smaller but still significant association with social stress (OR 1.11, 95% CI 1.01–1.21). The associations remained significant after exclusion of participants with first- and second-degree family history of breast disease. The presence of multiple forms of stress did not synergistically increase risk. The neutrophil–lymphocyte ratio (NLR), a marker of systemic inflammation and prognostic marker for breast cancer, was not associated with BBD. Psychosocial stress, particularly work-related and financial stress, is associated with increased risk of benign breast disease among young Chinese women.

Elevated serum mitochondrial DNA in females and lack of altered platelet mitochondrial methylation in patients with Parkinson´s disease.

Abstract: Purpose: Mitochondrial dysfunction has long been considered in the pathogenesis of Parkinson's disease (PD). This is evident from the presence of mitochondrial DNA deletions in substantia nigra neu...

DNA methylation patterns of LINE-1 and Alu for pre-symptomatic dementia in type 2 diabetes.

Abstract: The identification of early markers of dementia is important for higher-risk populations such as those with type 2 diabetes (T2D). Retrotransposons, including long interspersed nuclear element 1 (LINE-1) and Alu, comprise ~40% of the human genome. Although dysregulation of these retrotransposons can induce aberrant gene regulation and genomic instability, their role in the development of pre-symptomatic dementia (PSD) among T2D patients is unknown. Here, we examined locus-specific changes in LINE-1 and Alu methylation in PSD and the potential to offset these changes via supplementation with folate and vitamin B12. We interrogated DNA methylation patterns corresponding to 22,352 probes for LINE-1 and Alu elements using publicly-available Illumina Infinium 450K methylation datasets from i) an 18-month prospective study in 28 T2D patients (GSE62003) and ii) an intervention study in which 44 individuals were supplemented with folic acid (400 μg/day) and vitamin B12 (500 μg/day) over two years (GSE74548). We identified 714 differentially methylated positions (DMP) mapping to retrotransposons in T2D patients who developed PSD in comparison to those who did not (PFDR < 0.05), comprised of 2.4% (228 probes) of all LINE-1 probes and 3.8% (486 probes) of all Alu probes. These loci were enriched in genes with functions related to Alzheimer's disease and cognitive decline, including GNB5, GNG7 and PKN3 (p < 0.05). In older individuals supplemented with folate/vitamin B12, 85 (11.9%) PSD retrotransposon loci showed significant changes in methylation (p < 0.05): participants with the MTHFR CC genotype predominantly showed hypermethylation at these loci, while hypomethylation was observed more frequently in those with the TT genotype. In T2D patients, LINE-1 and Alu elements are differentially methylated in PSD in a locus-specific manner and may offer clinical utility in monitoring risk of dementia. Further work is required to examine the potential for dietary supplementation in lowering the risk of PSD.

Novel Zinc-Related Differentially Methylated Regions in Leukocytes of Women With and Without Obesity

Abstract: Introduction Nutriepigenetic markers are predictive responses associated with changes in “surrounding” environmental conditions of humans, which may influence metabolic diseases. Although rich in calories, Western diets could be linked with the deficiency of micronutrients, resulting in the downstream of epigenetic and metabolic effects and consequently in obesity. Zinc (Zn) is an essential nutrient associated with distinct biological roles in human health. Despite the importance of Zn in metabolic processes, little is known about the relationship between Zn and epigenetic. Thus, the present study aimed to identify the epigenetic variables associated with Zn daily ingestion (ZnDI) and serum Zinc (ZnS) levels in women with and without obesity. Materials and Methods This is a case-control, non-randomized, single-center study conducted with 21 women allocated into two groups: control group (CG), composed of 11 women without obesity, and study group (SG), composed of 10 women with obesity. Anthropometric measurements, ZnDI, and ZnS levels were evaluated. Also, leukocyte DNA was extracted for DNA methylation analysis using 450 k Illumina BeadChips. The epigenetic clock was calculated by Horvath method. The chip analysis methylation pipeline (ChAMP) package selected the differentially methylated regions (DMRs). Results The SG had lower ZnS levels than the CG. Moreover, in SG, the ZnS levels were negatively associated with the epigenetic age acceleration. The DMR analysis revealed 37 DMRs associated with ZnDI and ZnS levels. The DMR of PM20D1 gene was commonly associated with ZnDI and ZnS levels and was hypomethylated in the SG. Conclusion Our findings provide new information on Zn's modulation of DNA methylation patterns and bring new perspectives for understanding the nutriepigenetic mechanisms in obesity.

The ageing epigenome and its rejuvenation.

Abstract: Ageing is characterized by the functional decline of tissues and organs and the increased risk of ageing-associated disorders. Several 'rejuvenating' interventions have been proposed to delay ageing and the onset of age-associated decline and disease to extend healthspan and lifespan. These interventions include metabolic manipulation, partial reprogramming, heterochronic parabiosis, pharmaceutical administration and senescent cell ablation. As the ageing process is associated with altered epigenetic mechanisms of gene regulation, such as DNA methylation, histone modification and chromatin remodelling, and non-coding RNAs, the manipulation of these mechanisms is central to the effectiveness of age-delaying interventions. This Review discusses the epigenetic changes that occur during ageing and the rapidly increasing knowledge of how these epigenetic mechanisms have an effect on healthspan and lifespan extension, and outlines questions to guide future research on interventions to rejuvenate the epigenome and delay ageing processes.

Diet and depression: exploring the biological mechanisms of action

Abstract: The field of nutritional psychiatry has generated observational and efficacy data supporting a role for healthy dietary patterns in depression onset and symptom management. To guide future clinical trials and targeted dietary therapies, this review provides an overview of what is currently known regarding underlying mechanisms of action by which diet may influence mental and brain health. The mechanisms of action associating diet with health outcomes are complex, multifaceted, interacting, and not restricted to any one biological pathway. Numerous pathways were identified through which diet could plausibly affect mental health. These include modulation of pathways involved in inflammation, oxidative stress, epigenetics, mitochondrial dysfunction, the gut microbiota, tryptophan-kynurenine metabolism, the HPA axis, neurogenesis and BDNF, epigenetics, and obesity. However, the nascent nature of the nutritional psychiatry field to date means that the existing literature identified in this review is largely comprised of preclinical animal studies. To fully identify and elucidate complex mechanisms of action, intervention studies that assess markers related to these pathways within clinically diagnosed human populations are needed.

Potential reversal of epigenetic age using a diet and lifestyle intervention: a pilot randomized clinical trial.

Abstract: Manipulations to slow biological aging and extend healthspan are of interest given the societal and healthcare costs of our aging population. Herein we report on a randomized controlled clinical trial conducted among 43 healthy adult males between the ages of 50-72. The 8-week treatment program included diet, sleep, exercise and relaxation guidance, and supplemental probiotics and phytonutrients. The control group received no intervention. Genome-wide DNA methylation analysis was conducted on saliva samples using the Illumina Methylation Epic Array and DNAmAge was calculated using the online Horvath DNAmAge clock (2013). The diet and lifestyle treatment was associated with a 3.23 years decrease in DNAmAge compared with controls (p=0.018). DNAmAge of those in the treatment group decreased by an average 1.96 years by the end of the program compared to the same individuals at the beginning with a strong trend towards significance (p=0.066). Changes in blood biomarkers were significant for mean serum 5-methyltetrahydrofolate (+15%, p=0.004) and mean triglycerides (-25%, p=0.009). To our knowledge, this is the first randomized controlled study to suggest that specific diet and lifestyle interventions may reverse Horvath DNAmAge (2013) epigenetic aging in healthy adult males. Larger-scale and longer duration clinical trials are needed to confirm these findings, as well as investigation in other human populations.

One-year Mediterranean diet promotes epigenetic rejuvenation with country- and sex-specific effects: a pilot study from the NU-AGE project

Abstract: Mediterranean diet has been proposed to promote healthy aging, but its effects on aging biomarkers have been poorly investigated. We evaluated the impact of a 1-year Mediterranean-like diet in a pilot study including 120 elderly healthy subjects from the NU-AGE study (60 Italians, 60 Poles) by measuring the changes in their epigenetic age, assessed by Horvath’s clock. We observed a trend towards epigenetic rejuvenation of participants after nutritional intervention. The effect was statistically significant in the group of Polish females and in subjects who were epigenetically older at baseline. A genome-wide association study of epigenetic age changes after the intervention did not return significant (adjusted p value < 0.05) loci. However, we identified small-effect alleles (nominal p value < 10–4), mapping in genes enriched in pathways related to energy metabolism, regulation of cell cycle, and of immune functions. Together, these findings suggest that Mediterranean diet can promote epigenetic rejuvenation but with country-, sex-, and individual-specific effects, thus highlighting the need for a personalized approach to nutritional interventions.

Mitochondrial DNA Methylation and Human Diseases

Abstract: Epigenetic modifications of the nuclear genome, including DNA methylation, histone modifications and non-coding RNA post-transcriptional regulation, are increasingly being involved in the pathogenesis of several human diseases. Recent evidence suggests that also epigenetic modifications of the mitochondrial genome could contribute to the etiology of human diseases. In particular, altered methylation and hydroxymethylation levels of mitochondrial DNA (mtDNA) have been found in animal models and in human tissues from patients affected by cancer, obesity, diabetes and cardiovascular and neurodegenerative diseases. Moreover, environmental factors, as well as nuclear DNA genetic variants, have been found to impair mtDNA methylation patterns. Some authors failed to find DNA methylation marks in the mitochondrial genome, suggesting that it is unlikely that this epigenetic modification plays any role in the control of the mitochondrial function. On the other hand, several other studies successfully identified the presence of mtDNA methylation, particularly in the mitochondrial displacement loop (D-loop) region, relating it to changes in both mtDNA gene transcription and mitochondrial replication. Overall, investigations performed until now suggest that methylation and hydroxymethylation marks are present in the mtDNA genome, albeit at lower levels compared to those detectable in nuclear DNA, potentially contributing to the mitochondria impairment underlying several human diseases.