Environmental biodiversity, human microbiota, and allergy are interrelated

Abstract

Rapidly declining biodiversity may be a contributing factor to another global megatrend—the rapidly increasing prevalence of allergies and other chronic inflammatory diseases among urban populations worldwide. According to the “biodiversity hypothesis,” reduced contact of people with natural environmental features and biodiversity may adversely affect the human commensal microbiota and its immunomodulatory capacity. Analyzing atopic sensitization (i.e., allergic disposition) in a random sample of adolescents living in a heterogeneous region of 100 × 150 km, we show that environmental biodiversity in the surroundings of the study subjects’ homes influenced the composition of the bacterial classes on their skin. Compared with healthy individuals, atopic individuals had lower environmental biodiversity in the surroundings of their homes and significantly lower generic diversity of gammaproteobacteria on their skin. The functional role of the Gram-negative gammaproteobacteria is supported by in vitro measurements of expression of IL-10, a key anti-inflammatory cytokine in immunologic tolerance, in peripheral blood mononuclear cells. In healthy, but not in atopic, individuals, IL-10 expression was positively correlated with the abundance of the gammaproteobacterial genus Acinetobacter on the skin. These results raise fundamental questions about the consequences of biodiversity loss for both allergic conditions and public health in general.

Mapping cultural ecosystem services: A framework to assess the potential for outdoor recreation across the EU

“…The presented results provide information for planning future improvements in the rate of delivery of the service at different spatial scales. This is particularly important due to restorative health effects of outdoor activity, and the link between health and quality of nature in the surroundings of living places (Hanski et al, 2012;Bowler et al, 2010;Tzoulas et al, 2007;Cole and Hall, 2010; (Sievänen and Neuvonen 2011). The data was collected using a web-based survey supported by mail questionnaire.…”

Urban stress is associated with variation in microbial species composition—but not richness—in Manhattan

“…Globally, soil microbes are also a source of discovery in medicine and biotechnology (Bull, 2004;Challis, 2008), and conservation of microbial biodiversity is increasingly discussed (Colwell, 1997;Cockell and Jones, 2009;Sutherland et al, 2010;Bodelier, 2011). Furthermore, a growing literature suggests that the failure of children to be exposed to a diversity of microbes threatens the health of those children, particularly through its relation to allergic and autoimmune diseases (for example, Rook, 2009;Hanski et al, 2012). The large literature linking microbial diversity and human health tends to assume that the diversity of microbes to which children are exposed in urban environments is less than that in rural environments (for example, Hanski et al, 2012).…”

New therapeutic approaches for airway hyperimmune response are required

“…In a detailed investigation, a confirmation of "biodiversity hypothesis," has been made [6]. In this study it was shown that the atopic individuals had significantly lower generic diversity of gammaproteobacteria on their skin and lower environmental biodiversity of their homes compared with healthy individuals.…”