The purpose of this case series was to evaluate the presence of low Energy Availability (EA) and its impact on components of Relative Energy Deficiency in Sport (RED-S) in a population of female collegiate runners. Seven female NCAA Division I athletes (age: 22.3 ± 1.
View Article and Find Full Text PDFGenome-wide association studies have identified common genetic variants impacting human diseases; however, there are indications that the functional consequences of genetic polymorphisms can be distinct depending on cell type-specific contexts, which produce divergent phenotypic outcomes. Thus, the functional impact of genetic variation and the underlying mechanisms of disease risk are modified by cell type-specific effects of genotype on pathological phenotypes. In this study, we extend these concepts to interrogate the interdependence of cell type- and stimulation-specific programs influenced by the core autophagy gene and its T300A coding polymorphism identified by genome-wide association studies as linked with increased risk of Crohn's disease.
View Article and Find Full Text PDFObjectives: Limited research has examined the effects of fenugreek ( L.) supplementation to improve healthy younger men's aging male symptoms. The study objective was to examine whether a fenugreek seed extract would improve healthy men's aging male symptoms, health-related quality of life (HRQoL), grip strength, and anxiety.
View Article and Find Full Text PDFThe clear role of autophagy in human inflammatory diseases such as Crohn disease was first identified by genome-wide association studies and subsequently dissected in multiple mechanistic studies. ATG16L1 has been particularly well studied in knockout and hypomorph settings as well as models recapitulating the Crohn disease-associated T300A polymorphism. Interestingly, ATG16L1 has a single homolog, ATG16L2, which is independently implicated in diseases, including Crohn disease and systemic lupus erythematosus.
View Article and Find Full Text PDFInflammatory bowel disease (IBD) is driven by dysfunction between host genetics, the microbiota, and immune system. Knowledge gaps remain regarding how IBD genetic risk loci drive gut microbiota changes. The Crohn's disease risk allele T300A results in abnormal Paneth cells due to decreased selective autophagy, increased cytokine release, and decreased intracellular bacterial clearance.
View Article and Find Full Text PDFIdentifying immunodominant T cell epitopes remains a significant challenge in the context of infectious disease, autoimmunity, and immuno-oncology. To address the challenge of antigen discovery, we developed a quantitative proteomic approach that enabled unbiased identification of major histocompatibility complex class II (MHCII)-associated peptide epitopes and biochemical features of antigenicity. On the basis of these data, we trained a deep neural network model for genome-scale predictions of immunodominant MHCII-restricted epitopes.
View Article and Find Full Text PDFserovar Typhimurium (. Typhimurium) is a major cause of acute gastroenteritis in humans. During infection, reactive oxygen species (ROS), generated from NADPH oxidase (a multisubunit enzyme complex), are required for pathogen killing upon phagocytosis and for regulating pro-inflammatory signaling in phagocytic cells.
View Article and Find Full Text PDFIntegrin signalling triggers cytoskeletal rearrangements, including endocytosis and exocytosis of integrins and other membrane proteins. In addition to recycling integrins, this trafficking can also regulate intracellular signalling pathways. Here we describe a role for αv integrins in regulating Toll-like receptor (TLR) signalling by modulating intracellular trafficking.
View Article and Find Full Text PDFCARD9 is a central component of anti-fungal innate immune signaling via C-type lectin receptors, and several immune-related disorders are associated with CARD9 alterations. Here, we used a rare CARD9 variant that confers protection against inflammatory bowel disease as an entry point to investigating CARD9 regulation. We showed that the protective variant of CARD9, which is C-terminally truncated, acted in a dominant-negative manner for CARD9-mediated cytokine production, indicating an important role for the C terminus in CARD9 signaling.
View Article and Find Full Text PDFStudies of human genetics and pathophysiology have implicated the regulation of autophagy in inflammation, neurodegeneration, infection, and autoimmunity. These findings have motivated the use of small-molecule probes to study how modulation of autophagy affects disease-associated phenotypes. Here, we describe the discovery of the small-molecule probe BRD5631 that is derived from diversity-oriented synthesis and enhances autophagy through an mTOR-independent pathway.
View Article and Find Full Text PDFThe balance between Th17 and T regulatory (Treg) cells critically modulates immune homeostasis, with an inadequate Treg response contributing to inflammatory disease. Using an unbiased chemical biology approach, we identified a novel role for the dual specificity tyrosine-phosphorylation-regulated kinase DYRK1A in regulating this balance. Inhibition of DYRK1A enhances Treg differentiation and impairs Th17 differentiation without affecting known pathways of Treg/Th17 differentiation.
View Article and Find Full Text PDFDeveloping a quantitative view of how biological pathways are regulated in response to environmental factors is central for understanding of disease phenotypes. We present a computational framework, named Multivariate Inference of Pathway Activity (MIPA), which quantifies degree of activity induced in a biological pathway by computing five distinct measures from transcriptomic profiles of its member genes. Statistical significance of inferred activity is examined using multiple independent self-contained tests followed by a competitive analysis.
View Article and Find Full Text PDFA coding polymorphism (Thr300Ala) in the essential autophagy gene, autophagy related 16-like 1 (ATG16L1), confers increased risk for the development of Crohn disease, although the mechanisms by which single disease-associated polymorphisms contribute to pathogenesis have been difficult to dissect given that environmental factors likely influence disease initiation in these patients. Here we introduce a knock-in mouse model expressing the Atg16L1 T300A variant. Consistent with the human polymorphism, T300A knock-in mice do not develop spontaneous intestinal inflammation, but exhibit morphological defects in Paneth and goblet cells.
View Article and Find Full Text PDFPatients with chronic granulomatous disease (CGD) have a mutated NADPH complex resulting in defective production of reactive oxygen species; these patients can develop severe colitis and are highly susceptible to invasive fungal infection. In NADPH oxidase-deficient mice, autophagy is defective but inflammasome activation is present despite lack of reactive oxygen species production. However, whether these processes are mutually regulated in CGD and whether defective autophagy is clinically relevant in patients with CGD is unknown.
View Article and Find Full Text PDFBackground & Aims: Intestinal epithelial cells aid in mucosal defense by providing a physical barrier against entry of pathogenic bacteria and secreting antimicrobial peptides (AMPs). Autophagy is an important component of immune homeostasis. However, little is known about its role in specific cell types during bacterial infection in vivo.
View Article and Find Full Text PDFBackground & Aims: Caspase recruitment domain 9 (CARD9) is an adaptor protein that integrates signals downstream of pattern recognition receptors. CARD9 has been associated with autoinflammatory disorders, and loss-of-function mutations have been associated with chronic mucocutaneous candidiasis, but the role of CARD9 in intestinal inflammation is unknown. We characterized the role of Card9 in mucosal immune responses to intestinal epithelial injury and infection.
View Article and Find Full Text PDFAutophagy is a conserved homeostatic process in which cytoplasmic contents are degraded and recycled. Two ubiquitin-like conjugation pathways are required for the generation of autophagosomes, and ATG5 is necessary for both of these processes. Studies of mice deficient in ATG5 reveal a key role for autophagy in T lymphocyte function, as well as in B cell development and B-1a B cell maintenance.
View Article and Find Full Text PDFNADPH oxidase is a multisubunit complex that assembles during phagocytosis to generate reactive oxygen species. Several components of this complex have been implicated in chronic granulomatous disease and Crohn's disease, highlighting the importance of reactive oxygen species in regulating host immune response. In this study, we use genetically deficient mice to elucidate how p40(phox), one subunit of the NADPH oxidase complex, functions during intestinal inflammation.
View Article and Find Full Text PDFEBV is associated with systemic lupus erythematosus (SLE), but how it might contribute to the etiology is not clear. Since EBV-encoded latent membrane protein 2A (LMP2A) interferes with normal B cell differentiation and function, we sought to determine its effect on B cell tolerance. Mice transgenic for both LMP2A and the Ig transgene 2-12H specific for the ribonucleoprotein Smith (Sm), a target of the immune system in SLE, develop a spontaneous anti-Sm response.
View Article and Find Full Text PDFMurine autoreactive anti-Smith (Sm) B cells are negatively regulated by anergy and developmental arrest, but are also positively selected into the marginal zone (MZ) and B-1 B-cell populations. Despite positive selection, anti-Sm production occurs only in autoimmune-prone mice. To investigate autoreactive B-cell activation, an anti-Sm transgene was combined with the lpr mutation, a mutation of the proapoptotic gene Fas (Fas(lpr)), on both autoimmune (MRL) and nonautoimmune backgrounds.
View Article and Find Full Text PDFAb-secreting plasma cells (PCs) are the effectors of humoral immunity. In this study, we describe regulation of autoreactive B cells specific for the ribonucleoprotein Smith (Sm) at an early pre-PC stage. These cells are defined by the expression of the PC marker CD138 and normal levels of CD19 and B220.
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