Effect of vitamin D treatments on plasma metabolism and immune parameters of healthy dairy cows.
Arch Anim Nutr. 2018 Mar 21;:1-16
Authors: Yue Y, Hymøller L, Jensen SK, Lauridsen C
The objective of this study was to investigate the possible beneficial effect of vitamin D repletion on certain immune parameters of vitamin D insufficient dairy cows. Twenty dairy cows in late lactation were treated daily with vitamin D in five different ways: sunlight exposure (SUN), D2 supplementation combined with sunlight exposure (D2SUN), D2 supplementation (D2), D3 supplementation (D3), and D2 and D3 supplementation combined (D2D3). The cows had very low vitamin D levels at d 0 because of the vitamin D deprivation before the study. After 1 month of vitamin D repletion, all cows had plasma 25(OH)D levels within the normal range. Total 25(OH)D concentration was significantly higher in SUN, D2SUN and D2D3 than D2 or D3 at the end of the study. However, milk yield, as well as protein and fat content of the milk, was not influenced by vitamin D treatments. There was no difference obtained in the measured immune parameters: Leucocyte populations, somatic cell count, immunoglobulin concentrations in plasma and milk, and antigen-stimulated cytokine productions did not change in response to vitamin D repletion or difference in vitamin D sources, and no relations to plasma 25(OH)D levels were identified. Despite the fact that plasma 25(OH)D increased from a very low level to normal range, the present study did not show any effect of vitamin D repletion on the tested immune parameters of healthy dairy cows. Therefore, in this study, it was concluded that repletion to physiologically normal plasma 25-hydroxyvitamin D levels of vitamin D-depleted healthy dairy cows had no influence on immune parameters.
PMID: 29561174 [PubMed - as supplied by publisher]
[Skin diseases associated with environmental factors].
Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz. 2017 Jun;60(6):605-617
Authors: Mahler V
BACKGROUND: Multiple environmental exposures may derange the regulatory and repair mechanisms of the skin and lead to dermatological disease.
OBJECTIVES: Provide an overview of non-allergic skin diseases associated with environmental factors.
MATERIALS AND METHODS: Review of current scientific evidence for associations of non-allergic skin diseases with environmental exposures: irritation, chemicals, infection, UV-radiation, temperature.
RESULTS: Predisposition (constitution e. g. for atopic dermatitis, psoriasis and filaggrin gene mutations) and exposure (environment) are crucial for disease development or maintenance of health in an individual. Specific chemical and contagious agents lead to characteristic skin diseases (e. g. halogen acne) which under certain conditions may be recognized as occupational disease. The most frequent cause for irritant contact dermatitis is water (wet work). Natural optical radiation of different wavelength may cause light-induced inflammatory skin diseases. Phototoxic reactions due to psoralens, furocoumarins and drugs are frequent. The polymorphous light eruption is not an exogenous delayed type allergy, but seems to be a reaction against a UV-induced neoantigen of the skin. UVB exhibits direct mutagenic effects on DNA. Sun exposure and defective DNA-repair mechanisms are risk factors for skin tumors. Heat/cold exposure under specific conditions also triggers skin diseases (primary: congelations, frostbite, heat burn, scalding, chronic-inducible urticaria; secondary: deterioration of preexisting inflammatory diseases (e. g. systemic sclerosis)).
CONCLUSIONS: To keep the skin healthy, an early identification and elimination of harmful environmental factors and treatment of early disease stages is necessary. This requires strategies of environmental prevention and behavioral prevention, as well as global action (e. g. with regard to increasing incidence of skin cancer).
PMID: 28516256 [PubMed - indexed for MEDLINE]
The oxidative stress in the liver of Carassius auratus exposed to acesulfame and its UV irradiance products.
Sci Total Environ. 2016 Nov 15;571:755-62
Authors: Ren Y, Geng J, Li F, Ren H, Ding L, Xu K
Acesulfame (ACE) is listed as an emerging contaminant due to its environmental persistence and wide occurrence in the environment. ACE can be degraded partially in the regular UV disinfection process but the eco-toxicity of its irradiation products remains unclear. This study focused on the possible oxidative status change in the liver of Carassius auratus exposed to ACE and its irradiation products. The UV degradation of ACE follows pseudo-first-order kinetics, and eight irradiation products were identified. Fish were exposed 7days to 0.1 and 10mg/L ACE (ACE group) and ACE after UV irradiance (ACE-UV group). The oxidative stress in fish liver exposed to ACE group had no distinct change. However, in the ACE-UV group, the quantity of OH was induced by 17.96-55% and the MDA content increased by 16.28-68.28% compared to control. Time-effect exposure in the ACE-UV group showed that in the first 3days the quantity of OH reached its peak, causing severe inhibition of SOD and continuous inducement of GPx. GSH helped scavenge OH and decreased below control after 3days. An increased toxicity of ACE after UV irradiance was observed and its transfer after into aquatic environment needs to be recognized as an environmental risk.
PMID: 27443459 [PubMed - indexed for MEDLINE]