Background: Particulate matter (PM), a major component of ambient air pollution, accounts for a substantial burden of diseases and fatality worldwide. Maternal exposure to PM during pregnancy is particularly harmful to children’s health since this is a phase of rapid human growth and development.Method: In this review, we synthesize the scientific evidence on adverse health outcomes in children following prenatal exposure to the smallest toxic components, fine (PM2.5) and ultrafine (PM0.1) PM. We highlight the established and emerging findings from epidemiologic studies and experimental models.Results: Maternal exposure to fine and ultrafine PM directly and indirectly yields numerous adverse birth outcomes and impacts on children’s respiratory systems, immune status, brain development, and cardiometabolic health. The biological mechanisms underlying adverse effects include direct placental translocation of ultrafine particles, placental and systemic maternal oxidative stress and inflammation elicited by both fine and ultrafine PM, epigenetic changes, and potential endocrine effects that influence long-term health.Conclusion: Policies to reduce maternal exposure and health consequences in children should be a high priority. PM2.5levels are regulated, yet it is recognized that minority and low socioeconomic status groups experience disproportionate exposures. Moreover, PM0.1levels are not routinely measured or currently regulated. Consequently, preventive strategies that inform neighborhood/regional planning and clinical/nutritional recommendations are needed to mitigate maternal exposure and ultimately protect children’s health.
Changes in the microbial populations on the skin of animals have traditionally been evaluated using conventional microbiology techniques. The sequencing of bacterial 16S rRNA genes has revealed that the human skin is inhabited by a highly diverse and variable microbiome that had previously not been demonstrated by culture-based methods. The goals of this study were to describe the microbiome inhabiting different areas of the canine skin, and to compare the skin microbiome of healthy and allergic dogs. DNA extracted from superficial skin swabs from healthy (n = 12) and allergic dogs (n = 6) from different regions of haired skin and mucosal surfaces were used for 454-pyrosequencing of the 16S rRNA gene. Principal coordinates analysis revealed clustering for the different skin sites across all dogs, with some mucosal sites and the perianal regions clustering separately from the haired skin sites. The rarefaction analysis revealed high individual variability between samples collected from healthy dogs and between the different skin sites. Higher species richness and microbial diversity were observed in the samples from haired skin when compared to mucosal surfaces or mucocutaneous junctions. In all examined regions, the most abundant phylum and family identified in the different regions of skin and mucosal surfaces were Proteobacteria and Oxalobacteriaceae. The skin of allergic dogs had lower species richness when compared to the healthy dogs. The allergic dogs had lower proportions of the Betaproteobacteria Ralstonia spp. when compared to the healthy dogs. The study demonstrates that the skin of dogs is inhabited by much more rich and diverse microbial communities than previously thought using culture-based methods. Our sequence data reveal high individual variability between samples collected from different patients. Differences in species richness was also seen between healthy and allergic dogs, with allergic dogs having lower species richness when compared to healthy dogs.
1 November 2014 in Journal of Comparative Pathology
The antidiabetic drug metformin exhibits both chemopreventive and chemotherapeutic activity for multiple cancers including pancreatic cancer; however, the underlying mechanism of action of metformin is unclear. A recent study showed that metformin down-regulated specificity protein (Sp) transcription factors (TFs) Sp1, Sp3, and Sp4 in pancreatic cancer cells and tumors, and this was accompanied by down-regulation of several pro-oncogenic Sp-regulated genes. Treatment with metformin or down-regulation of Sp TFs by RNAi also inhibits two major pro-oncogenic pathways in pancreatic cancer cells, namely mammalian target of rapamycin (mTOR) signaling and epidermal growth factor (EGFR)-dependent activation of Ras. Metformin and Sp knockdown by RNAi decreased expression of the insulin-like growth factor-1 receptor (IGF-1R), resulting in inhibition of mTOR signaling. Ras activity was also decreased by metformin and Sp knockdown of EGFR, another Sp-regulated gene. Thus, the antineoplastic activities of metformin in pancreatic cancer are due, in part, to down-regulation of Sp TFs and Sp-regulated IGF-1R and EGFR, which in turn results in inhibition of mTOR and Ras signaling, respectively.
The microbiome is the complex collection of microorganisms, their genes, and their metabolites, colonizing the human and animal mucosal surfaces, digestive tract, and skin. It is now well known that the microbiome interacts with its host, assisting in digestion and detoxification, supporting immunity, protecting against pathogens, and maintaining health. Studies published to date have demonstrated that healthy individuals are often colonized with different microbiomes than those with disease involving various organ systems. This review covers a brief history of the development of the microbiome field, the main objectives of the Human Microbiome Project, and the most common microbiomes inhabiting the human respiratory tract, companion animal digestive tract, and skin in humans and companion animals. The main changes in the microbiomes in patients with pulmonary, gastrointestinal, and cutaneous lesions are described.
Background and Purpose: Approaches to prevent selective and progressive loss of insulin‐producing beta cells in Type 1 diabetes mellitus (T1DM) will help to manage this prevalent and devastating disease. Curcumin (CUR), a natural anti‐inflammatory substance, suppresses diabetes‐associated inflammation and cell death. However, very high doses need to be used because of poor oral bioavailability, making it difficult to translate the anti‐inflammatory actions to clinical situations.Experimental Approach: We have prepared biodegradable nanosystems encapsulating curcumin (nCUR), resulting in at least nine‐fold improvement in oral bioavailability. Here, we tested the ability of nCUR to prevent streptozotocin (STZ)‐induced inflammation and apoptosis in pancreatic islets and beta cells, in rats.Key Results: Non‐fasted rats pretreated with 10 or 50 mg·kg−1 nCUR 6 h prior to STZ challenge had up to 37% reduction in the glucose levels, while plain CUR (50 mg·kg−1) results in 12% reduction. This treatment with nCUR was accompanied by decreased islet or beta cell death, as shown by TUNEL assay and H&E staining. Both CUR and nCUR significantly decreased levels of inflammatory cytokines in pancreatic tissue homogenates that correlated well with minimal histiocytic infiltration. Pre‐treatment with nCUR, but not CUR, decreased 8‐oxo‐2′‐deoxyguanosine, a sensitive biomarker of ROS‐induced DNA damage, in pancreas. In normal rodents, daily dosing for 28 days, with nCUR (25‐100 mg·kg−1) did not cause any deleterious health issues by the carrier.Conclusions and Implications: Together, these data indicate a potentially translatable dose of nCUR that is safe and efficacious in improving beta cell function, which could prevent T1DM.