Prenatal physical activity and the gut microbiota of pregnant women: results from a preliminary investigation.

PURPOSE: To determine whether physical activity (PA), specifically meeting the recommended 150 minutes of moderate-intensity PA per week, is associated with gut microbiota composition in pregnant women. METHODS: In an ongoing birth cohort study, questions from the Behavioral Risk Factor Surveillance System, which provides data on PA variables, were used to determine whether pregnant women met or exceeded the PA recommendations. To profile the composition of gut bacterial microbiota, 16S rRNA sequencing was performed on stool samples obtained from pregnant women. Differences in alpha diversity metrics (richness, Pielou's evenness, and Shannon's diversity) according to PA were determined using linear regression, whereas beta diversity relationships (Canberra and Bray-Curtis) were assessed using Permutational multivariate analysis of variance (PERMANOVA). Differences in relative taxon abundance were determined using DESeq2. RESULTS: The complete analytical sample included 23 women that were evaluated for both PA and 16S rRNA sequencing data (median age [Q1; Q3] = 30.5 [26.6; 34.0] years; 17.4% Black), and 11 (47.8%) met or exceeded the PA recommendations. Meeting or exceeding the PA recommendations during pregnancy was not associated with gut microbiota richness, evenness, or diversity, but it was related to distinct bacterial composition using both Canberra (p = 0.005) and Bray-Curtis (p = 0.022) distances. Significantly lower abundances of Bacteroidales, Bifidobacteriaceae, Lactobacillaceae, and Streptococcaceae were observed in women who met or exceeded the PA recommendations (all false discovery rates adjusted, p < 0.02). CONCLUSION: Pregnant women who met or exceeded the PA recommendations showed altered gut microbiota composition. This study forms the basis for future studies on the impact of PA on gut microbiota during pregnancy.

Effects of aflatoxin on the immune system: Evidence from human and mammalian animal research.

Shortly after its discovery in 1960, aflatoxin - a group of fungal toxins or mycotoxins produced by the fungi Aspergillus flavus and A. parasiticus in food crops such as maize, peanuts and tree nuts - was found to cause liver cancer in humans and multiple animal species. Hence, regulations on maximum allowable aflatoxin levels in food worldwide have focused on protecting humans from aflatoxin's carcinogenic effects. However, aflatoxin may also have non-carcinogenic health effects (e.g., immunotoxicity) that are particularly relevant today. Our current review highlights the growing evidence that aflatoxin exposure adversely affects immunity. Here, we comprehensively evaluated human and mammalian animal studies that link aflatoxin exposure with adverse effects on the immune system. We organized the review by organism as well as by the effects on adaptive and innate immune functions. There is abundant evidence that aflatoxin exhibits immunotoxicity, and therefore may compromise the ability of both humans and animals to resist infections. However, the reported effects of aflatoxin on certain specific immune biomarkers are inconsistent in the existing literature. The extent of the immunotoxic effects of aflatoxin must be clarified, so that the contribution of such immunotoxicity to the overall burden of aflatoxin-related diseases can be established.

Perinatal risk factors for fecal antibiotic resistance gene patterns in pregnant women and their infants.

Perinatal factors can shape fecal microbiome patterns among pregnant women and their infants. However, there is scarce information about the effect of maternal demographics and perinatal exposures on antibiotic resistance genes (ARG) and mobile genetic element (MGE) patterns in pregnant women and infants. We examined fecal samples from pregnant women during their third trimester of pregnancy (n = 51) and 6-month-old infants (n = 40). Of the 91 participants, 72 represented 36 maternal-infant dyads, 15 were additional pregnant women, and 4 were additional infants. We assessed the effects of demographics, pre-pregnancy BMI, smoking and parity in the pregnancy resistome and the effects of demographics, delivery mode, feeding habits and prenatal antibiotic treatment on the infancy resistome. ARG and MGE richness and abundance were assessed using a SmartChip qPCR-array. Alpha diversity (Shannon and Inverse Simpson index) and beta diversity (Sorensen and Bray-Curtis index) were calculated. The Wilcoxon and the Kruskal non-parametric test were used for comparisons. There is a high variability in shared resistome patterns between pregnant women and their infants. An average of 29% of ARG and 24% of MGE were shared within dyads. Infants had significantly greater abundance and higher diversity of ARG and MGE compared to pregnant women. Pregnancy and infancy samples differed in ARG and MGE gene composition and structure. Composition of the fecal resistome was significantly associated with race in pregnant women, with non-white women having different patterns than white women, and, in infants, with extent of solid food consumption. Our data showed that the pregnancy and infancy resistome had different structure and composition patterns, with maternal race and infant solid food consumption as possible contributors to ARG. By characterizing resistome patterns, our results can inform the mechanism of antibiotic resistome development in pregnant women and their infants.

Compliance to Prenatal Iron and Folic Acid Supplement Use in Relation to Low Birth Weight in Lilongwe, Malawi.

Prenatal iron and folic acid (IFA) supplements are offered free to all pregnant women in Malawi to reduce maternal anemia and improve birth outcomes. We investigated the association between self-reported compliance to IFA intake and risk of low birth weight (LBW). Pregnant women who attended Bwaila Maternity Wing of Lilongwe District Hospital for delivery were recruited (n = 220). We used a questionnaire to collect self-reported information on IFA use and maternal sociodemographic data. Before delivery, blood samples for maternal hemoglobin (Hb) and folate status, and upon delivery, birth weight, and other newborn anthropometrics were measured. We used multivariable logistic regression to determine risk of LBW by prenatal IFA intake. The self-reported number of IFA pills taken during pregnancy was positively associated with Hb, but not serum and RBC folate concentration: <45, 45⁻89 and ≥90 pills taken corresponded with mean (SD) Hb 10.7 (1.6), 11.3 (1.8), and 11.7 (1.6) g/dL, respectively (p = 0.006). The prevalence of LBW was 20.1%, 13.5% and 5.6% for those who reported taking IFA pills <45, 45⁻89, and ≥90 pills, respectively (p = 0.027). Taking >60 IFA pills reduced risk of LBW delivery (OR (95% CI) = 0.15 (0.03⁻0.70), p = 0.033) than taking ≤30 pills. Self-reported compliance to IFA use is valid for assessing prenatal supplement program in Malawi, especially Hb status, and can reduce the rate of LBW.

Boiling and Frying Peanuts Decreases Soluble Peanut (Arachis Hypogaea) Allergens Ara h 1 and Ara h 2 But Does Not Generate Hypoallergenic Peanuts.

Peanut allergy continues to be a problem in most developed countries of the world. We sought a processing method that would alter allergenic peanut proteins, such that allergen recognition by IgE from allergic individuals would be significantly reduced or eliminated. Such a method would render accidental exposures to trace amounts of peanuts safer. A combination of boiling and frying decreased recovery of Ara h 1 and Ara h 2 at their expected MWs. In contrast, treatment with high pressures under varying temperatures had no effect on protein extraction profiles. Antibodies specific for Ara h 1, Ara h 2, and Ara h 6 bound proteins extracted from raw samples but not in boiled/fried samples. However, pre-incubation of serum with boiled/fried extract removed most raw peanut-reactive IgE from solution, including IgE directed to Ara h 1 and 2. Thus, this method of processing is unlikely to generate a peanut product tolerated by peanut allergic patients. Importantly, variability in individual patients' IgE repertoires may mean that some patients' IgE would bind fewer polypeptides in the sequentially processed seed.

Altered Saturated and Monounsaturated Plasma Phospholipid Fatty Acid Profiles in Adult Males with Colon Adenomas.

BACKGROUND: Altered lipid metabolism and plasma fatty acid (FA) levels are associated with colorectal cancer. Obesity and elevated waist circumference (WC) increase the likelihood of developing precancerous colon adenomas. METHODS: Venous blood was collected from 126 males, ages 48 to 65 years, who received routine colonoscopies. Plasma phospholipid (PPL) FAs were isolated, derivatized, and then analyzed using gas chromatography. ORs and 95% confidence intervals were determined using polytomous logistic regression after adjusting for confounding factors [i.e., age, smoking, WC, and body mass index (BMI)]. RESULTS: PPL palmitic acid (PA) was inversely correlated with the presence of colon adenomas (P = 0.01). For each unit increase in palmitoleic acid (OR, 3.75; P = 0.04) or elaidic acid (OR, 2.92; P = 0.04), an individual was more likely to have adenomas relative to no colon polyps. Higher enzyme activity estimates (EAE) of stearoyl-CoA desaturase-1 (SCD-1; P = 0.02) and elongation of very long chain fatty acids protein-6 (ELOVL-6; P = 0.03) were associated with an individual being approximately 1.5 times more likely to have an adenoma compared with no polyps. CONCLUSIONS: PPL FAs and EAEs, which have previously been associated with colorectal cancer, are significantly different in those with adenomas when compared with those without polyps. PPL PA, elaidic acid, and SCD-1 and ELOVL-6 EAEs are associated with adenomas independent of BMI and WC. IMPACT: PPL PA, elaidic acid, and SCD-1 and ELOVL-6 EAEs are associated with adenomas even after adjusting for obesity-related risk factors and may function as novel biomarkers of early colorectal cancer risk.

Association of serum cytokines with colorectal polyp number and type in adult males.

Chronic inflammation contributes to colorectal carcinogenesis. To determine whether serum cytokines are associated with colon polyps, 126 asymptomatic men (48-65 years) were recruited during colonoscopy. Serum cytokine concentrations were measured. Odds ratios were determined using polytomous logistic regression for polyp number and type. Men with serum monocyte chemotactic protein-3 (MCP-3) or soluble interleukin-4 receptor (sIL-4R) concentrations in the highest tertile were 0.2 times less likely to have three or more polyps relative to no polyps. For each increase in serum MCP-3 or sIL-4R tertile a man was about 0.4 times less likely to have three or more polyps than to have no polyps. Men with serum concentrations of interferon-α2 (IFN-α2) or interleukin (IL)-7 in the highest tertile were three times more likely to have an adenoma than no polyps. Those with serum IL-8 concentrations in the highest tertile were four times more likely to have an adenoma than no polyps. For each increase in serum IFN-α2, IL-7, or IL-8 tertile an individual was 1.8 times more likely to have an adenoma than to have no polyps. Serum concentrations of MCP-3, sIL-4R, IFN-α2, IL-7, and IL-8 may indicate which men are more likely to have colorectal polyps.

High levels of fish oil enhance neutrophil development and activation and influence colon mucus barrier function in a genetically susceptible mouse model.

Dietary fatty acids influence immunologic homeostasis, but their effect on initiation of colitis, an immune-mediated disease, is not well established. Previously, our laboratory demonstrated that high doses of dietary fish oil (FO) increased colon inflammation and dysplasia in a model of infection-induced colitis. In the current study, we assessed the effects of high-dose dietary FO, 6% by weight, on colon inflammation, neutrophil recruitment and function, and mucus layer integrity in a genetically susceptible, colitis-prone mouse model in the absence of infection. FO-fed SMAD3(-/-) mice had increased colon inflammation evidenced by increased numbers of systemic and local neutrophils and increased neutrophil chemoattractant and inflammatory cytokine gene expression in the colon. Mucus layer thickness in the cecum and goblet cell numbers in the cecum and colon in FO-fed mice were reduced compared to control. FO consumption affected colitis in male and female mice differently. Compared to female control mice, neutrophils from FO-fed female mice had reduced reactive oxygen species (ROS) upon ex vivo stimulation with phorbol myristate acetate while FO-fed male mice produced increased ROS compared to control-fed male mice. In summary, dietary FO impaired mucus layer integrity and was associated with colon inflammation characterized by increased neutrophil numbers and altered neutrophil function. High-dose FO may have detrimental effects in populations genetically susceptible for inflammatory bowel disease and these effects may differ between males and females.

Dietary bovine lactoferrin increases intestinal cell proliferation in neonatal piglets.

Lactoferrin is a bioactive milk protein that stimulates cell proliferation in vitro; however, limited in vivo evidence exists to allow lactoferrin to be incorporated into infant formula. Herein, the effect of dietary bovine lactoferrin (bLF) on neonatal intestinal growth and maturation was investigated guided by the hypothesis that bLF would increase cellular proliferation leading to functional differences in neonatal piglets. Colostrum-deprived piglets were fed formula containing 0.4 [control (Ctrl)], 1.0 (LF1), or 3.6 (LF3) g bLF/L for the first 7 or 14 d of life. To provide passive immunity, sow serum was provided orally during the first 36 h of life. Intestinal cell proliferation, histomorphology, mucosal DNA concentration, enzyme activity, gene expression, and fecal bLF content were measured. Intestinal enzyme activity, DNA concentration, and villus length were unaffected by bLF. However, crypt proliferation was 60% greater in LF1- and LF3-fed piglets than in Ctrl piglets, and crypt depth and area were 20% greater in LF3-fed piglets than in Ctrl piglets. Crypt cells from LF3-fed piglets had 3-fold higher ß-catenin mRNA expression than did crypt cells from Ctrl piglets. Last, feces of piglets fed bLF contained intact bLF, suggesting that some bLF was resistant to digestion and could potentially affect intestinal proliferation through direct interaction with intestinal epithelial cells. This study is the first to our knowledge to show that dietary bLF stimulates crypt cell proliferation in vivo. The increased ß-catenin expression indicates that Wnt signaling may in part mediate the stimulatory effect of bLF on intestinal cell proliferation.

Association of insulin-related serum factors with colorectal polyp number and type in adult males.

BACKGROUND: Dysregulated insulin signaling is thought to contribute to cancer risk. METHODS: To determine if insulin-related serum factors are associated with colon polyps, 126 asymptomatic men (48-65 years) were recruited at colonoscopy. Blood was collected. Odds ratios were determined using polytomous logistic regression for polyp number and type. RESULTS: Males with serum C-peptide concentration >3.3 ng/mL were 3.8 times more likely to have an adenoma relative to no polyp than those with C-peptide ≤1.8 ng/mL. As C-peptide tertile increased, an individual was 2 times more likely to have an adenoma (P = 0.01) than no polyp. There were no associations between insulin-like growth factor or its binding proteins with polyp number or type. Males with soluble receptor for advanced glycation end products (sRAGE) concentration >120.4 pg/mL were 0.25 times less likely to have ≥3 polyps relative to no polyps compared with males with sRAGE ≤94.5 pg/mL. For each increase in sRAGE tertile, a man was 0.5 times less likely to have ≥3 polyps than no polyps (P = 0.03). Compared with males with a serum vascular endothelial growth factor (VEGF) concentration ≤104.7 pg/mL, males with a serum VEGF concentration >184.2 pg/mL were 3.4 times more likely to have ≥3 polyps relative to no polyps. As the VEGF tertile increased, a man was 1.9 times more likely to have ≥3 polyps than no polyps (P = 0.049). CONCLUSIONS: Serum concentrations of C-peptide, sRAGE, and VEGF may indicate which men could benefit most from colonoscopy. IMPACT: Identification of biomarkers could reduce medical costs through the elimination of colonoscopies on low-risk individuals.

Cross-sectional analysis of obesity and serum analytes in males identifies sRAGE as a novel biomarker inversely associated with diverticulosis.

Diverticulosis can lead to diverticulitis, a colon condition involving inflammation and other complications. Diverticulosis can result from biological, behavioral, or genetic causes. However, the etiology of diverticulosis is unknown. Although diet is associated with diverticulosis, recent studies suggest other factors influence risk. We sought to identify anthropometric or serum markers that were associated with the presence of diverticulosis. To determine these associations, 126 asymptomatic men (48-65 yr) were recruited at the time of preventative screening colonoscopy. Anthropometric measures were taken, and blood was collected for serum protein analysis. Data were analyzed by logistic regression and factor analysis. Obese individuals (BMI >30) were 7.8 (CI: 2.3-26.3) times more likely than normal weight (BMI <25) individuals to have diverticulosis. The relationship was similar for waist circumference. Individuals with a waist circumference >45 inches were 8.1 (CI: 2.8-23.8) times more likely to have diverticulosis than those with a waist circumference <38 inches. Leptin was also positively associated with diverticulosis (OR = 5.5, CI: 2.0-14.7). Both low molecular weight adiponectin (LMW, OR = 0.50; CI: 0.3-0.8) and the soluble receptor for advanced glycation end products (sRAGE, OR = 0.4, CI: 0.3-0.7) were inversely related to the presence of diverticulosis. sRAGE levels were not correlated with leptin or C-peptide concentrations. The pattern of high BMI, waist circumference, leptin and C-peptide increased the odds of diverticulosis while the pattern of high levels of sRAGE and LMW adiponectin decreased the odds of diverticulosis. Associations between diverticulosis and anthropometric or serum markers may elucidate the origins of diverticulosis and may enable physicians to identify individuals at risk for diverticulitis.

Dietary bovine lactoferrin alters mucosal and systemic immune cell responses in neonatal piglets.

Lactoferrin (LF) is a multifunctional immune protein found at high concentrations in human milk. Herein, the effect of dietary bovine LF (bLF) on mucosal and systemic immune development was investigated. Colostrum-deprived piglets were fed formula containing 130 [control (Ctrl)], 367 (LF1), or 1300 (LF3) mg of bLF/(kg body weight · d). To provide passive immunity, sow serum was provided orally during the first 36 h of life. Blood, spleen, mesenteric lymph node (MLN), and ascending colon (Asc) contents were collected on day 7 (n = 10-14/group) and day 14 (n = 10-12/group). Immune cell populations were quantified by flow cytometry and immunoglobulins (Igs) were measured by ELISA. Additionally, immune cells were isolated from spleen and MLNs (n = 7/group) on day 7 and stimulated ex vivo with phytohemagglutinin or lipopolysaccharide (LPS) ± LF for 72 h. Secreted cytokine concentrations were quantified by multiplex assay. Lymphocyte populations [cluster determinant (CD)4, CD8, and natural killer cells] developed normally and were unaffected by dietary bLF. LF3 piglets tended to have 1.4 to 2 times more serum IgG than Ctrl piglets (P = 0.07) or LF1 piglets (P = 0.03), but IgA in Asc contents was unaffected by bLF. Asc IgA was 4 times higher on day 14 than day 7. Spleen cells from LF3 piglets produced 2 times more interleukin (IL)-10 and tumor necrosis factor (TNF)-α ex vivo than those from Ctrl or LF1 piglets. MLN cells from LF1 and LF3 piglets produced 40% more IL-10 and tended to produce 40% more IL-6 (P = 0.05) than those from Ctrl piglets. However, ex vivo bLF did not affect the cytokine response of spleen or MLN cells to LPS. In summary, dietary bLF alters the capacity of MLN and spleen immune cells to respond to stimulation, supporting a role for LF in the initiation of protective immune responses in these immunologically challenged neonates.

Adipokines and obesity are associated with colorectal polyps in adult males: a cross-sectional study.

BACKGROUND: Obesity increases the risk of colon cancer. It is also known that most colorectal cancers develop from adenomatous polyps. However, the effects of obesity and adipokines on colonic polyp formation are unknown. METHODS: To determine if BMI, waist circumference or adipokines are associated with colon polyps in males, 126 asymptomatic men (48-65 yr) were recruited at time of colonoscopy, and anthropometric measures as well as blood were collected. Odds ratios were determined using polytomous logistic regression for polyp number (0 or ≥3) and polyp type (no polyp, hyperplastic polyp, tubular adenoma). RESULTS: 41% of the men in our study were obese (BMI ≥30). The odds of an obese individual having ≥3 polyps was 6.5 (CI: 1.3-33.0) times greater than those of a lean (BMI<25) individual. Additionally, relative to lean individuals, obese individuals were 7.8 (CI: 2.0-30.8) times more likely to have a tubular adenoma than no polyp. As BMI category increased, participants were 2.9 (CI: 1.5-5.4) times more likely to have a tubular adenoma than no polyps. Serum leptin, IP-10 and TNF-α were significantly associated with tubular adenoma presence. Serum leptin and IP-10 were significantly associated with increased likelihood of ≥3 polyps, and TNF-α showed a trend (p = 0.09). CONCLUSIONS: Obese men are more likely to have at least three polyps and adenomas. This cross-sectional study provides evidence that colonoscopy should be recommended for obese, white males.

Effect of walnut (Juglans regia) polyphenolic compounds on ovalbumin-specific IgE induction in female BALB/c mice.

English walnuts are implicated in severe, IgE-mediated food allergy in humans. We sought to determine if polyphenolic compounds extracted from the edible nut could promote IgE production to a coadministered allergen. BALB/c mice were sensitized to ovalbumin (OVA) with or without alum (AL) or polyphenolic-enriched extract via intraperitoneal injection. Serum was analyzed for total IgE and OVA-specific IgE, IgG(1,) and IgG(2a/2b). Coadministration of walnut polyphenolic-enriched extract with antigen and AL increased serum concentrations of antigen-specific IgE and IgG(1). When AL was excluded from the injections, polyphenolic extract tended to enhance OVA-specific IgE and IgG(1) over levels induced by OVA alone, but the increase did not reach significance. Serum IgG(2a/2b) levels were similar between mice receiving OVA/AL and OVA/AL with polyphenolics. Thus, walnut polyphenolic extract enhanced the Th2-skewing effect of an aluminum hydroxide adjuvant. This indicates that walnut polyphenolic compounds may play a role in allergic sensitization of genetically predisposed individuals.

Endoplasmic reticulum-associated degradation-induced dissociation of class II invariant chain complexes containing a glycosylation-deficient form of p41.

The quality control system in the secretory pathway can identify and eliminate misfolded proteins through endoplasmic reticulum-associated degradation (ERAD). ERAD is thought to occur by retrotranslocation through the Sec61 complex into the cytosol and degradation by the proteasome. However, the extent of disassembly of oligomeric proteins and unfolding of polypeptide chains that is required for retrotranslocation is not fully understood. In this report we used a glycosylation mutant of the p41 isoform of invariant chain (Ii) to evaluate the ability of ERAD to discriminate between correctly folded and misfolded subunits in an oligomeric complex. We show that loss of glycosylation at position 239 of p41 does not detectably affect Ii trimerization or association with class II but does result in a defect in endoplasmic reticulum export of Ii that ultimately leads to its degradation via the ERAD pathway. Although class II associated with the mutated form of p41 is initially retained in the endoplasmic reticulum, it is subsequently released and traffics through the Golgi to the plasma membrane. ERAD-mediated degradation of the mutant p41 is dependent on mannose trimming and inhibition of mannosidase I stabilizes Ii. Interestingly, inhibition of mannosidase I also results in prolonged association between the mutant Ii and class II, indicating that complex disassembly and release of class II is linked to mannosidase-dependent ERAD targeting of the misfolded Ii. These results suggest that the ERAD machinery can induce subunit disassembly, specifically targeting misfolded subunits to degradation and sparing properly folded subunits for reassembly and/or export.