Am J Physiol Gastrointest Liver Physiol
January 2024
Concentrated animal feeding operations (CAFOs) are responsible for the production of global greenhouse gases and harmful environmental pollutants including hydrogen sulfide, ammonia, and particulate matter. Swine farmers are frequently exposed to organic dust that is proinflammatory in the lung and are thus at greater risk of developing pneumonia, asthma, and other respiratory conditions. In addition to respiratory disease, air pollutants are directly associated with altered gastrointestinal (GI) physiology and the development of GI diseases, thereby highlighting the gut-lung axis in disease progression.
View Article and Find Full Text PDFMacrophages intimately interact with intestinal epithelial cells, but the consequences of defective macrophage-epithelial cell interactions for protection against enteric pathogens are poorly understood. Here, we show that in mice with a deletion in protein tyrosine phosphatase nonreceptor type 2 (PTPN2) in macrophages, infection with Citrobacter rodentium, a model of enteropathogenic and enterohemorrhagic E. coli infection in humans, promoted a strong type 1/IL-22-driven immune response, culminating in accelerated disease but also faster clearance of the pathogen.
View Article and Find Full Text PDFSystemic inflammation is associated with chronic disease and is purported to be a main pathogenic mechanism underlying metabolic conditions. Microbes harbored in the host gastrointestinal tract release signaling byproducts from their cell wall, such as lipopolysaccharides (LPS), which can act locally and, after crossing the gut barrier and entering circulation, also systemically. Defined as metabolic endotoxemia, elevated concentrations of LPS in circulation are associated with metabolic conditions and chronic disease.
View Article and Find Full Text PDFAims: To characterize neuroinflammatory and gut dysbiosis signatures that accompany exaggerated exercise fatigue and cognitive/mood deficits in a mouse model of Gulf War Illness (GWI).
Methods: Adult male C57Bl/6N mice were exposed for 28 d (5 d/wk) to pyridostigmine bromide (P.O.
The epithelial barrier forms the interface between luminal microbes and the host immune system and is the first site of exposure to many of the environmental factors that trigger disease activity in chronic inflammatory bowel disease (IBD). Disruption of the epithelial barrier, in the form of increased intestinal permeability, is a feature of IBD and other inflammatory diseases, including celiac disease and type 1 diabetes. Variants in genes that regulate or belong to the JAK-STAT signaling pathway are associated with IBD risk.
View Article and Find Full Text PDFMacrophages are a heterogeneous population of innate immune cells that are often divided into two major subsets: classically activated, typically pro-inflammatory (M1) macrophages that mediate host defense, and alternatively activated, tolerance-inducing (M2) macrophages that exert homeostatic and tissue-regenerative functions. Disturbed macrophage function/differentiation results either in inadequate, excessive immune activation or in a failure to induce efficient protective immune responses against pathogens. Loss-of-function variants in protein tyrosine phosphatase non-receptor type 2 (PTPN2) are associated with chronic inflammatory disorders, but the effect of macrophage-intrinsic PTPN2 loss is still poorly understood.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
April 2021
As countries continue to industrialize, major cities experience diminished air quality, whereas rural populations also experience poor air quality from sources such as agricultural operations. These exposures to environmental pollution from both rural and populated/industrialized sources have adverse effects on human health. Although respiratory diseases (e.
View Article and Find Full Text PDFBackground: A main mechanism of action proposed for oral probiotic supplementation is immunomodulation, which is expected to impart health benefits in the host by influencing circulating immune and inflammatory factors. To date, the effectiveness of probiotic supplementation for immunomodulation in healthy adults without disease has not been evaluated in a systematic review.
Objective: The objective of this systematic review was to evaluate the effect of probiotic supplementation on circulating immune and inflammatory markers of healthy adults compared to placebo.
Comp Biochem Physiol B Biochem Mol Biol
November 2019
Urbanization influences food quality and availability for many wild species, but our knowledge of the consequences urbanization has on the nutritional physiology of these animals is currently limited. To fill this gap, we captured House Sparrows (Passer domesticus) from rural and urban environments and hypothesized that increased access to human refuse in urban areas may significantly alter the gut microbiome and nutritional physiology of Sparrows. While there were no significant differences in circulating triglycerides or free glycerol concentrations between populations, urban birds had significantly greater blood glucose concentrations, which suggests greater circulating glucagon concentrations, accessibility to carbohydrates, and/or higher rates of gluconeogenesis in an urban setting.
View Article and Find Full Text PDFThe prevalence of metabolic syndrome (MetSyn) has risen 35% since 2012 and over two-thirds of Americans exhibit features characterizing this condition (obesity, dyslipidemia, hyperglycemia, insulin resistance and/or endothelial dysfunction). The aim of this study was to evaluate the effects of a novel dietary supplemental organic mineral complex (OMC) on these risk factors in a rodent model of MetSyn. Six-week old male Sprague-Dawley rats were fed either standard chow or a high-fat diet (HFD) composed of 60% kcal from fat for 10 weeks.
View Article and Find Full Text PDFEnergy-dense foods can alter gut microbial diversity. However, the physiological effects of diet-induced microbial changes on the development of nonalcoholic fatty liver disease (NAFLD) remain debatable. We hypothesized that high-fat intake for 6 weeks would promote intestinal dysbiosis by increasing gram-positive bacteria, inducing the intestinal production of proinflammatory cytokines and subsequent hepatic lipid infiltration in young male rats.
View Article and Find Full Text PDFNeuropsychol Dev Cogn B Aging Neuropsychol Cogn
March 2018
The present study investigated whether cognitively healthy older adults who are carriers of the ε4 allele of apolipoprotein E, the most prevalent genetic risk factor for late-onset Alzheimer's disease, benefit from self-referential processing and emotional processing to the same degree as noncarriers of this gene. Participants encoded emotional and nonemotional narratives using a baseline-orienting task, semantic elaboration, or imagination-based self-referential processing and then completed a recognition memory test. Both groups of older adults showed enhanced recognition memory for narrative information following self-referential processing relative to semantic elaboration, and the magnitude of this memory effect was not affected by ε4 status.
View Article and Find Full Text PDF