Chronic sun exposure is associated with distinct histone acetylation changes in human skin.
Br J Dermatol. 2017 Nov 18;:
Authors: Ding S, Chen J, Zeng Q, Lu J, Tan L, Guo A, Kang J, Yang S, Xiang Y, Zuo C, Huang J
BACKGROUND: Photoaging is attributed to continuous sunlight or artificial UV exposure and manifests the clinical and histological changes of skin. Epigenetic changes have been found to be involved in the pathogenesis of photoaging. However, the underlying mechanisms are unclear.
OBJECTIVES: To analyse histone modification patterns in sun-exposed and non-exposed skins, and identify the abnormally histone modified-genes related to photoaging.
METHODS: Skin biopsies were collected both from the outer forearm (sun-exposed area) and the buttock (sun-protected area) in 20 healthy middle-aged female volunteers. Global histone H3/H4 acetylation and H3K4/H3K9 methylation statuses were assessed by ELISA. Expression levels of HATs and HDACs were measured by RT-qPCR and western blot. ChIP-chip assay with anti-acetyl-histone H3 antibody in sun-exposed Pool (combining six sun-exposed skin samples) and non-exposed Pool (combining six non-exposed skin samples) was conducted to explore the abnormal histone H3 acetylation genes related to photoaging, then ChIP-qPCR was followed to verify the results of ChIP-chip.
RESULTS: We observed higher global histone H3 acetylation level, increased P300 and decreased HDAC1 and SIRT1 expression in sun-exposed skins, compared with matched non-exposed skins. Further, ChIP-chip assay results showed that 227 genes displayed significant hyperacetylation of histone H3, and 81 genes displayed significant hypoacetylation of histone H3 between the two groups. Histone H3 acetylations levels on the promoters of PDCD5, ITIH5, MMP1 and AHR were positively correlated with the mRNA expression of the corresponding gene.
CONCLUSIONS: Chronic sun exposure induced histone H3 hyperacetylation may play a critical role in the pathogenesis of skin photoaging. This article is protected by copyright. All rights reserved.
PMID: 29150847 [PubMed - as supplied by publisher]
Impact of Multidecadal Climate Variability on United Kingdom Rickets Rates.
Sci Rep. 2017 Nov 17;7(1):15764
Authors: Majeed H, Moore GWK
Children who receive inadequate exposure to sunlight have reduced levels of vitamin D, resulting in rickets, a disease that is characterized by bone deformity, stunted growth, and long term pronounced disability. The United Kingdom rickets incidence rates declined from the early 1960's to mid-1990's, after which there was a dramatic increase. The reason for this change is not well understood. Here we show that an important low frequency mode of climate variability, the Atlantic Multidecadal Oscillation (AMO), with a period of ~60-80 years, has an impact on rickets incidence rates in the United Kingdom through changes in sea level pressure, cloud cover and sunshine duration. This research highlights the important role that multidecadal climate variability can play in human morbidity and suggests that future changes in the AMO may modulate rickets incidence rates throughout the United Kingdom.
PMID: 29150647 [PubMed - in process]
A review of prevalence studies of Autism Spectrum Disorder by latitude and solar irradiance impact.
Med Hypotheses. 2017 Nov;109:19-24
Authors: Syed S, Moore KA, March E
Autism Spectrum Disorder (ASD) is a lifelong disability with no known cause or cure. Among the suggested etiologies, is Cannell's hypothesis of a deficiency in Vitamin D the main natural source of which is Solar Ultraviolet-B (UVB) radiation. The aim in this paper is to build on this hypothesis and explore the relationship of solar irradiance of which UVB is a component, by latitude with the prevalence rates of ASD. Twenty-five reports published between 2011 and 2016 using comparable diagnostic criteria were reviewed. The results suggest a tendency for the prevalence rates of ASD to be lowest in countries near the equator and for this rate to increase as the latitude increases. These findings provide some support not just for the Vitamin D hypothesis, but also for a new proposition that along with UVB radiation, the entire solar radiation spectrum which reaches the earth, may play a role in ASD. While these results are both novel and encouraging in terms of the potential efficacy of exposure to natural sunlight, further research is warranted before results can be considered definitive, and before the implications of the findings can be implemented clinically.
PMID: 29150285 [PubMed - in process]