scholarly journals Ultraviolet Irradiation of Skin Alters the Faecal Microbiome Independently of Vitamin D in Mice

Nutrients ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 1069 ◽  
Author(s):  
Simon Ghaly ◽  
Nadeem Kaakoush ◽  
Frances Lloyd ◽  
Lavinia Gordon ◽  
Cynthia Forest ◽  
...  

Reduced sunlight exposure has been associated with an increased incidence of Crohn’s disease and ulcerative colitis. The effect of ultraviolet radiation (UVR) on the faecal microbiome and susceptibility to colitis has not been explored. C57Bl/6 female mice were fed three different vitamin D-containing diets for 24 days before half of the mice in each group were UV-irradiated (1 kJ/m2) for each of four days, followed by twice-weekly irradiation of shaved dorsal skin for 35 days. Faecal DNA was extracted and high-throughput sequencing of the 16S RNA gene performed. UV irradiation of skin was associated with a significant change in the beta-diversity of faeces compared to nonirradiated mice, independently of vitamin D. Specifically, members of phylum Firmicutes, including Coprococcus, were enriched, whereas members of phylum Bacteroidetes, such as Bacteroidales, were depleted. Expression of colonic CYP27B1 increased by four-fold and IL1β decreased by five-fold, suggesting a UVR-induced anti-inflammatory effect. UV-irradiated mice, however, were not protected against colitis induced by dextran sodium sulfate (DSS), although distinct faecal microbiome differences were documented post-DSS between UV-irradiated and nonirradiated mice. Thus, skin exposure to UVR alters the faecal microbiome, and further investigations to explore the implications of this in health and disease are warranted.

2013 ◽  
Vol 39 (5) ◽  
pp. 458-484 ◽  
Author(s):  
G. C. DeLuca ◽  
S. M. Kimball ◽  
J. Kolasinski ◽  
S. V. Ramagopalan ◽  
G. C. Ebers

2021 ◽  
Vol 12 ◽  
Author(s):  
Harini Narayanam ◽  
Suresh V. Chinni ◽  
Sumitha Samuggam

The role of micronutrients in health and disease has increased the curiosity and interest among researchers. The prime focus of this review is the significance of trace elements- calcium, vitamin D, selenium and zinc with cardiovascular health. WHO identified cardiovascular diseases (CVD) as the leading cause of deaths globally. Identifying the risk factors that could be modified and creating new treatment strategies remains to be the main concern for CVD prevention. The data that showed the relationship between trace elements and various ways in which they may contribute to cardiovascular health and disease from clinical trials and observational studies were collected from databases such as PubMed and Embase. Based on these collected data, it shows that either high or low circulating serum levels can be associated with the development of cardiovascular diseases. Micronutrients through diet contribute to improved cardiac health. However, due to our current lifestyle, there is a huge dependency on dietary supplements. Based on the observational studies, it is evident that supplements cause sudden increase in the circulating levels of the nutrients and result in cardiovascular damage. Thus, it is advisable to restrict the use of supplements, owing to the potent risks it may cause. In order to understand the exact mechanism between micronutrients and cardiac health, more clinical studies are required.


Botany ◽  
2021 ◽  
Author(s):  
Samir Djouadi ◽  
Amina Bouherama ◽  
Fatiha AID ◽  
Saïd Amrani

La présente étude porte sur la nature des rhizobia associés aux légumineuses du genre Hippocrepis L. qui compte une dizaine d’espèces en Algérie et pour laquelle très peu de travaux ont été jusqu’ici consacrés. Les résultats de nos investigations qui ont portés sur 26 plants représentant 8 espèces de ce genre et provenant de 17 localités du nord et du sud du pays révèlent que tous les plants étaient nodulés et fixateurs d’azote, ce qui indique que les 8 espèces identifiées sont capables d’établir une symbiose efficiente avec les rhizobia présents dans les sols qui les supportent. Le séquençage du gène de l’ARN 16S des 26 souches de rhizobia isolées et authentifiées par des tests de nodulation au laboratoire, permet de les assigner à 16 espèces de rhizobia réparties sur 5 genres : Ensifer, Mesorhizobium, Bradyrhizobium, Rhizobium et Neorhizobium avec une prédominance des représentants des genres Ensifer et Mesorhizobium. Les résultats de cette étude qui est la première dédiée spécifiquement au genre Hippocrepis indiquent que la symbiose à rhizobia et la capacité d’utiliser, par ce biais, l’azote atmosphérique sont communes chez les représentants de ce genre en Algérie, ils révèlent aussi la grande diversité des rhizobia qui sont associés à ce genre. Abstract: The present study focuses on the nature of the rhizobia associated with legumes of the genus Hippocrepis L. which counts about ten species in Algeria and for which very little work has been performed so far. The results of our investigations, which focused on 26 plants representing 8 species of this genus and coming from 17 localities in the north and south of the country, show that all plants were nodulated and nitrogen-fixing, which indicates that the species identified are capable of establishing an efficient symbiosis with the rhizobia present in the soils that support them. The sequencing of the 16S RNA gene of the 26 strains of rhizobia isolated and authenticated by nodulation tests in the laboratory, allows their assignation to16 species of rhizobia spread over 5 genera: Ensifer, Mesorhizobium, Bradyrhizobium, Rhizobium and Neorhizobium with a predominance of representatives of the genera Ensifer and Mesorhizobium. The results of this study, which is the first dedicated to the genus Hippocrepis, show that the rhizobial symbiosis and its ability to use atmospheric nitrogen are common among representatives of the genus Hippocrepis in Algeria and reveal a great diversity of associated rhizobia


Metabolites ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 371 ◽  
Author(s):  
Emma A. Hurst ◽  
Natalie Z. Homer ◽  
Richard J. Mellanby

The demand for vitamin D analysis in veterinary species is increasing with the growing knowledge of the extra-skeletal role vitamin D plays in health and disease. The circulating 25-hydroxyvitamin-D (25(OH)D) metabolite is used to assess vitamin D status, and the benefits of analysing other metabolites in the complex vitamin D pathway are being discovered in humans. Profiling of the vitamin D pathway by liquid chromatography tandem mass spectrometry (LC-MS/MS) facilitates simultaneous analysis of multiple metabolites in a single sample and over wide dynamic ranges, and this method is now considered the gold-standard for quantifying vitamin D metabolites. However, very few studies report using LC-MS/MS for the analysis of vitamin D metabolites in veterinary species. Given the complexity of the vitamin D pathway and the similarities in the roles of vitamin D in health and disease between humans and companion animals, there is a clear need to establish a comprehensive, reliable method for veterinary analysis that is comparable to that used in human clinical practice. In this review, we highlight the differences in vitamin D metabolism between veterinary species and the benefits of measuring vitamin D metabolites beyond 25(OH)D. Finally, we discuss the analytical challenges in profiling vitamin D in veterinary species with a focus on LC-MS/MS methods.


2020 ◽  
Vol 3 (Supplement_1) ◽  
pp. 15-16
Author(s):  
E S Bosman ◽  
A Y Albert ◽  
J P Dutz ◽  
B Vallance

Abstract Background The recent worldwide rise in idiopathic immune and inflammatory diseases such as multiple sclerosis and inflammatory bowel diseases has been linked to Western society-based changes in lifestyle and environment. These include decreased exposure to sunlight/UVB light and subsequent impairment in the production of vitamin D, as well as dysbiotic changes in the makeup of the gut microbiome. Despite their association, it is unclear if there are any direct links between UVB light and the gut microbiome. Aims In this study we investigated whether exposing the skin to Narrow Band Ultraviolet B (NB-UVB) light to increase serum vitamin D levels would also modulate the makeup of the human intestinal microbiota. Methods The effects of NB-UVB light were studied in a clinical pilot study using a healthy human female cohort (n=21). Participants were divided into those that took vitamin D supplements throughout the winter prior to the start of the study (VDS+) and those who did not (VDS-). Results After three full-body NB-UVB light exposures within the same week, the serum 25(OH)D levels of participants increased on average 7.3 nmol/L. The serum response was negatively correlated to the starting 25-hydroxy vitamin D (25(OH)D) serum concentration. Fecal microbiota composition analysis using 16S rRNA sequencing showed that exposure to NB-UVB significantly increased alpha and beta diversity in the VDS- group whereas there were no changes in the VDS+ group. Bacteria from several families were enriched in the VDS- group after the UVB exposures according to a Linear Discriminant Analysis (LDA) prediction, including Lachnospiracheae, Rikenellaceae, Desulfobacteraceae, Clostridiales vadinBB60 group, Clostridia Family XIII, Coriobacteriaceae, Marinifilaceae, and Ruminococcus. The serum 25(OH)D concentrations showed a positive correlation with the relative abundance of the Lachnospiraceae, specifically members of the Lachnopsira and Fusicatenibacter genera. Conclusions This is the first study to show that humans with low 25(OH)D serum levels display overt changes in their intestinal microbiome in response to NB-UVB skin exposure and increases in 25(OH)D levels, suggesting the existence of a novel skin-gut axis that could be used to promote intestinal homeostasis and health. Funding Agencies NRCBC Childrens Hospital Research Institute


2020 ◽  
Vol 31 (9) ◽  
pp. 2026-2042 ◽  
Author(s):  
Sandra Rayego-Mateos ◽  
Jose Luis Morgado-Pascual ◽  
José Manuel Valdivielso ◽  
Ana Belén Sanz ◽  
Enrique Bosch-Panadero ◽  
...  

BackgroundCKD leads to vitamin D deficiency. Treatment with vitamin D receptor agonists (VDRAs) may have nephroprotective and anti-inflammatory actions, but their mechanisms of action are poorly understood.MethodsModulation of the noncanonical NF-κB2 pathway and its component TNF receptor–associated factor 3 (TRAF3) by the VDRA paricalcitol was studied in PBMCs from patients with ESKD, cytokine-stimulated cells, and preclinical kidney injury models.ResultsIn PBMCs isolated from patients with ESKD, TRAF3 protein levels were lower than in healthy controls. This finding was associated with evidence of noncanonical NF-κB2 activation and a proinflammatory state. However, PBMCs from patients with ESKD treated with paricalcitol did not exhibit these features. Experiments in cultured cells confirmed the link between TRAF3 and NF-κB2/inflammation. Decreased TRAF3 ubiquitination in K48-linked chains and cIAP1-TRAF3 interaction mediated the mechanisms of paricalcitol action.TRAF3 overexpression by CRISPR/Cas9 technology mimicked VDRA’s effects. In a preclinical model of kidney injury, paricalcitol inhibited renal NF-κB2 activation and decreased renal inflammation. In VDR knockout mice with renal injury, paricalcitol prevented TRAF3 downregulation and NF-κB2–dependent gene upregulation, suggesting a VDR-independent anti-inflammatory effect of paricalcitol.ConclusionsThese data suggest the anti-inflammatory actions of paricalcitol depend on TRAF3 modulation and subsequent inhibition of the noncanonical NF-κB2 pathway, identifying a novel mechanism for VDRA’s effects. Circulating TRAF3 levels could be a biomarker of renal damage associated with the inflammatory state.


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