Download full-text


Available from: Richard Beresford Weller, Sep 28, 2015
1 Follower
35 Reads
  • Source
    • "This analysis adds to the limited previous research addressing the relationship between sunlight and vascular health. Higher myocardial infarction, stroke, and adverse vascular risk factor rates have been reported in farther northern latitudes, but it is not clear whether this is due to environmental, social, or other factors [4,29,30]. There is also some evidence of higher myocardial infarction and stroke rates during the winter [1,31] although other research contradicts this [3]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Previous research has suggested that vitamin D and sunlight are related to cardiovascular outcomes, but associations between sunlight and risk factors have not been investigated. We examined whether increased sunlight exposure was related to improved cardiovascular risk factor status. Methods Residential histories merged with satellite, ground monitor, and model reanalysis data were used to determine previous-year sunlight radiation exposure for 17,773 black and white participants aged 45+ from the US. Exploratory and confirmatory analyses were performed by randomly dividing the sample into halves. Logistic regression models were used to examine relationships with cardiovascular risk factors. Results The lowest, compared to the highest quartile of insolation exposure was associated with lower high-density lipoprotein levels in adjusted exploratory (−2.7 mg/dL [95% confidence interval: −4.2, −1.2]) and confirmatory (−1.5 mg/dL [95% confidence interval: −3.0, −0.1]) models. The lowest, compared to the highest quartile of insolation exposure was associated with higher systolic blood pressure levels in unadjusted exploratory and confirmatory, as well as the adjusted exploratory model (2.3 mmHg [95% confidence interval: 0.8, 3.8]), but not the adjusted confirmatory model (1.6 mg/dL [95% confidence interval: −0.5, 3.7]). Conclusions The results of this study suggest that lower long-term sunlight exposure has an association with lower high-density lipoprotein levels. However, all associations were weak, thus it is not known if insolation may affect cardiovascular outcomes through these risk factors.
    BMC Neurology 06/2014; 14(1):133. DOI:10.1186/1471-2377-14-133 · 2.04 Impact Factor
  • Source
    • "Furthermore, it has been suggested that many of the beneficial effects of sunlight, particularly those related to cardiovascular health, are mediated by mechanisms that are independent of vitamin D production. For example, it has been hypothesized that photolabile nitric oxide (NO)-related species or compounds, such as nitrite and nitrosothiols, which are stored in comparably high concentration in the skin, can be mobilized by UVA and delivered to the systemic circulation, exerting coronary vasodilation and antihypertensive effects (see Figure 1) [7,8]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Human skin is exposed to solar ultraviolet radiation comprising UVB (280-315 nm) and UVA (315-400 nm) on a daily basis. Within the last two decades, the molecular and cellular response to UVA/UVB and the possible effects on human health have been investigated extensively. It is generally accepted that the mutagenic and carcinogenic properties of UVB is due to the direct interaction with DNA. On the other hand, by interaction with non-DNA chromophores as endogenous photosensitizers, UVA induces formation of reactive oxygen species (ROS), which play a pivotal role as mediators of UVA-induced injuries in human skin. This review gives a short overview about relevant findings concerning the molecular mechanisms underlying UVA/UVB-induced cell death. Furthermore, we will highlight the potential role of cutaneous antioxidants and photolabile nitric oxide derivates (NODs) in skin physiology. UVA-induced decomposition of the NODs, like nitrite, leads not only to non-enzymatic formation of nitric oxide (NO), but also to toxic reactive nitrogen species (RNS), like peroxynitrite. Whereas under antioxidative conditions the generation of protective amounts of NO is favored, under oxidative conditions, less injurious reactive nitrogen species are generated, which may enhance UVA-induced cell death.
    International Journal of Molecular Sciences 12/2012; 14(1):191-204. DOI:10.3390/ijms14010191 · 2.86 Impact Factor
  • Source
    • "NO2-, for a long time considered biologically inert at low concentrations, is now known, not only to dilate blood vessels in its own right, but also to protect organs against ischemia/reperfusion damage.136 Hemoglobin, myoglobin, xanthine oxidoreductase, cytochrome P-450, and mitochondrial enzymes can all generate NO• from NO2- under hypoxic conditions.135,137 In adults, skin and blood are of comparable weight and volume. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Most of the positive effects of solar radiation are mediated via ultraviolet-B (UVB) induced production of vitamin D in skin. However, several other pathways may exist for the action of ultraviolet (UV) radiation on humans as focused on in this review. One is induction of cosmetic tanning (immediate pigment darkening, persistent pigment darkening and delayed tanning). UVB-induced, delayed tanning (increases melanin in skin after several days), acts as a sunscreen. Several human skin diseases, like psoriasis, vitiligo, atopic dermatitis and localized scleroderma, can be treated with solar radiation (heliotherapy) or artificial UV radiation (phototherapy). UV exposure can suppress the clinical symptoms of multiple sclerosis independently of vitamin D synthesis. Furthermore, UV generates nitric oxide (NO), which may reduce blood pressure and generally improve cardiovascular health. UVA-induced NO may also have antimicrobial effects and furthermore, act as a neurotransmitter. Finally, UV exposure may improve mood through the release of endorphins.
    Dermato-Endocrinology 04/2012; 4(2):109-17. DOI:10.4161/derm.20013
Show more