Fecal Alpha Research Articles

Increased Intestinal Inflammation and Permeability in Glaucoma.

Evidence suggests that dysbiosis of the gut microbiota plays a pivotal role in the development of glaucoma. This dysbiosis is commonly associated with chronic intestinal inflammation and increased intestinal permeability. However, the understanding of intestinal inflammation and permeability in glaucoma remains insufficient. This study aims to investigate the potential relationship between fecal inflammation and permeability markers and glaucoma. We recruited 114 glaucoma patients and 75healthy controls. Levels of fecal lactoferrin (Lf) and alpha-1 antitrypsin (AAT) were quantified using enzyme linked immunosorbent assay (ELISA) to compare both biomarkers between groups and across different severity grades of glaucoma. Logistic regression analysis was used to assess the association between these fecal biomarkers and glaucoma. The severity of glaucoma was assessed based on the mean deviation (MD) in the visual field. In this study, we observed elevated levels of fecal Lf and AAT in glaucoma patients. The proportion of glaucoma patients with abnormal fecal Lf levels (≥ 7.25µg/g) was significantly higher than that of the controls (p = 0.012). A positive correlation was noted between fecal Lf and AAT (rho = 0.20, p = 0.006). After adjusting for age and sex, multivariable logistic regression analysis indicated that both fecal Lf (OR = 1.11, 95% CI: 1.01-1.21, p = 0.026) and AAT (OR = 1.01, 95% CI: 1.01-1.02, p < 0.001) positively correlated with glaucoma. These biomarkers might reflect glaucoma severity, with significant differences in fecal Lf levels observed between moderate and severe stages, but not in the early stage. Furthermore, increasing levels of fecal AAT correlated with greater severity of glaucomatous injury and a larger vertical cup-to-disc ratio (VCDR) (p < 0.05). This study suggests an increase in intestinal inflammation and permeability in glaucoma, further indicating the importance of the 'gut-retina axis' in the pathogenesis of the disease and potentially offering new therapeutic avenues.

Fecal, duodenal, and tumor microbiota composition of esophageal carcinoma patients, a longitudinal prospective cohort.

The microbiome has been associated with chemotherapy and immune checkpoint inhibitor efficacy. How this pertains to resectable esophageal carcinoma is unknown. Our aim was to identify microbial signatures in resectable esophageal carcinoma associated with response to neoadjuvant chemoradiotherapy with or without an immune checkpoint inhibitor. From 2 prospectively collected esophageal carcinoma cohorts (n = 172 in total) treated with neoadjuvant chemoradiotherapy alone (n = 132) or a combination of neoadjuvant chemoradiotherapy and an immune checkpoint inhibitor (n = 40), fecal samples were available at baseline, during treatment, and presurgery. Additionally, in the immune checkpoint inhibitor-treated patients, tumor and duodenal snap frozen biopsies were collected over time. Fecal, tumor, and duodenal DNA were extracted for 16S ribosomal RNA sequencing. Associations were investigated between microbiome composition pathological complete response and progression-free survival (PFS). There was a statistically significant shift in the microbiota profile of the fecal, tumor, and duodenal microbiota over time. In the total cohort, patients with a pathological complete response had a stable fecal alpha diversity, while the diversity of poor responders decreased during treatment (P = .036). Presurgery, lower alpha diversity (<4.12) was related to worse PFS (log-rank P = .025). Baseline tumor biopsies of patients with short PFS had more Fusobacterium. A low baseline duodenal alpha diversity (<3.96) was associated with worse PFS (log-rank P = .012). Lower intestinal alpha diversity was associated with worse response and survival of esophageal carcinoma patients. In tumor biopsies, Fusobacterium was more abundant in patients with poor PFS. After further mechanistic validation, these findings may aid in response prediction and the design of novel microbiome modulating treatments for esophageal carcinoma patients.

Spirulina (Arthrospira platensis) Improved Nonalcoholic Fatty Liver Disease Characteristics and Microbiota and Did Not Affect Organ Fibrosis Induced by a Fructose-Enriched Diet in Wistar Male Rats.

Spirulina (Arthrospira platensis) is reported to play a role in improving nonalcoholic fatty liver disease (NAFLD) and intestinal microbiota (IM). To study spirulina's effects in the improvement of NAFLD characteristics, IM, and pancreatic-renal lesions induced by a fructose-enriched diet, 40 Wistar healthy male rats, weighing 200-250 g, were randomly divided into four groups of 10, and each rat per group was assigned a diet of equal quantities (20 g/day) for 18 weeks. The first control group (CT) was fed a standardized diet, the second group received a 40% fructose-enriched diet (HFr), and the third (HFr-S5) and fourth groups (HFr-S10) were assigned the same diet composition as the second group but enriched with 5% and 10% spirulina, respectively. At week 18, the HFr-S10 group maintained its level of serum triglycerides and had the lowest liver fat between the groups. At the phylae and family level, and for the same period, the HFr-S10 group had the lowest increase in the Firmicutes/Bacteroidetes ratio and the Ruminococcaceae and the highest fecal alpha diversity compared to all other groups (p < 0.05). These findings suggest that at a 10% concentration, spirulina could be used in nutritional intervention to improve IM, fatty liver, metabolic, and inflammatory parameters associated with NAFLD.

296 Effects of dietary antimicrobials on the ruminant gastrointestinal tract microbiome

Abstract Monensin, tylosin, and chlortetracycline (CTC) are antimicrobials frequently employed in high grain feedlot cattle diets to inhibit liver abscesses and enhance growth. However, increased public concerns regarding antibiotic resistance have created a pressing need to develop alternative strategies. A more mechanistic understanding of how antimicrobial drugs effect the microbiome in the ruminant gastrointestinal tract (GIT) may help develop effective alternatives. Therefore, the objective of this study was to determine changes in the GIT microbiome of grain-fed feedlot steers after antimicrobial drug administration. Thirty individually housed Angus x Simmental steers [body weight (BW) = 355 ± 16.8 kg] previously fed a 56% forage diet were immediately transitioned to a 93% concentrate diet and assigned to one of three treatments (10 steers/treatment): 1) control, without antibiotics, 2) 75 mg of tylosin and 200 mg of monensin per animal per day (TYLMON), and 3) 70 mg of CTC per animal per day. Fecal samples were collected on d 0, 7, 14, 28, 56, 112, and at slaughter and digesta were obtained from the rumen, jejunum, and cecum at slaughter. DNA was extracted from samples, amplified via 16S PCR, and sequenced. Jejunal samples had the least alpha diversity compared with ruminal, cecal, or fecal samples (P &amp;lt; 0.001). There were no differences in measures of alpha diversity in the ruminal, jejunal, or cecal digesta at slaughter (P ≥ 0.10). However, overall measures of alpha diversity (Shannon entropy, observed features) in feces were greater in CTC-fed steers (P ≤ 0.009) as well as in TYLMON-fed steers (P ≤ 0.04) compared with control steers. Measures of alpha diversity for all treatments decreased in feces from d 0 to 7, then increased from d 7 to slaughter (time effect, (P ≤ 0.001). There were no differences in fecal alpha diversity between treatment groups on d 0 (P ≥ 0.50), but by d 28 both TYLMON and CTC treated steers had greater fecal alpha diversity compared with the control steers (P ≤ 0.05). With regard to differential abundance, Phascolarctobacterium and Prevotellaceae UCG-003 were more abundant in feces of control steers relative to antimicrobial treated steers (P &amp;lt; 0.05). Bifidobacterium, Dorea, CAG-56, and Erysipelotrichaceae UCG-003, were the 4 genera found to be in the greatest abundance in the feces of TYLMON-fed relative to control steers (P &amp;lt; 0.05). Akkermansia, Succinivibrio, and Turicbacter were the 3 genera found to be in the greatest abundance in the feces of CTC-fed compared with control steers (P &amp;lt; 0.05). Taken together, these data suggest that differences in the microbiome associated with dietary antimicrobial treatment occur to a greater extent in the lower sections of the GIT, and that these changes in the microbiome occur after 28 d of feeding.

Noninvasive Markers of Inflammation and Protein Loss Augment Diagnosis of Pediatric Celiac Disease.

Circulating tissue transglutaminase immunoglobulin A concentration is a sensitive and specific indicator of celiac disease, but discrepancies between serologic and histologic findings occur. We hypothesized that fecal markers of inflammation and protein loss would be greater in patients with untreated celiac disease than in healthy controls. Our study aims to evaluate multiple fecal and plasma markers in celiac disease and correlate these findings with serologic and histologic findings as noninvasive means of evaluating disease activity. Participants with positive celiac serologies and controls with negative celiac serologies were prospectively enrolled before upper endoscopy. Blood, stool, and duodenal biopsies were collected. Concentrations of fecal lipocalin-2, calprotectin, and alpha-1-antitrypsin and plasma lipocalin-2 were determined. Biopsies underwent modified Marsh scoring. Significance was tested between cases and controls, modified Marsh score and tissue transglutaminase immunoglobulin A concentration. Lipocalin-2 was significantly elevated in the stool ( P = 0.006) but not the plasma of participants with positive celiac serologies. There was no significant difference in fecal calprotectin or alpha-1 antitrypsin between participants with positive celiac serologies and controls. Fecal alpha-1 antitrypsin >100 mg/dL was specific, but not sensitive for biopsy-proven celiac disease. Lipocalin-2 is elevated in the stool but not the plasma of patients with celiac disease suggesting a role of local inflammatory response. Calprotectin was not a useful marker in the diagnosis of celiac disease. While random fecal alpha-1 antitrypsin was not significantly elevated in cases compared with controls, an elevation of greater than 100 mg/dL was 90% specific for biopsy-proven celiac disease.

The Effect of Dietary Protein Concentration on the Fecal Microbiome and Serum Concentrations of Gut-Derived Uremic Toxins in Healthy Adult Cats.

The purpose of this study was to evaluate the effect of feeding healthy adult cats with foods containing variable protein concentrations on the fecal microbiome and serum concentrations of the gut-derived uremic toxins indoxyl sulfate, p-cresol sulfate (pCS), and trimethylamine-n-oxide. Twenty healthy young adult cats were randomized into two groups and fed either a low-protein diet (LPD; 7.4 g/100 kcal ME) or a high-protein diet (HPD; 11.0 g/100 kcal ME) for a 12-week period. Serum uremic toxin concentrations were measured via liquid chromatography tandem mass spectrometry, and the fecal microbiome was characterized using shallow sequence shotgun metagenomics. Cats that consumed the HPD had higher pCS concentrations at 8 weeks (p = 0.028) when compared to baseline. After 12 weeks, cats fed the HPD had higher fecal alpha diversity indices at both the taxonomic and functional levels and lower fecal Bifidobacterium relative abundance compared to those cats fed the LPD. In conclusion, a change in diet and dietary protein concentration shifted the fecal microbial community and microbial function. Feeding cats a high amount of protein increased serum concentrations of the uremic toxin pCS; however, the effect was short-lived.

Exudative enteropathy in neonates: A case report

The term exudative gastroenteropathy is used to describe an entity characterized by excessive loss of plasma proteins in the gastrointestinal tract. This digestive exudation can be caused either by an obstacle to intestinal lymphatic drainage or by an alteration of the epithelial barrier. The clinical picture is often associated with chronic diarrhea and an edematous syndrome. Lymphedema, infectious complications secondary to lymphopenia or hypogammaglobulinemia, and thromboembolic complications may also be observed. Diagnosis is based on the measurement of fecal alpha-1 antitrypsin clearance. Sometimes primary in the context of Waldmann disease (primary intestinal lymphangiectasis) but more often secondary. It requires an endoscopic and morphological workup to confirm the origin of the protein leak, to evaluate its extent and cause. In addition to etiological treatment, management is based on a hyperprotein and hypolipid diet with medium-chain triglyceride supplementation. We report the case of an exudative enteropathy in a newborn.

Double-blinded placebo-controlled clinical trial of prophylactic omeprazole in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion.

Proton pump inhibitors are administered prophylactically in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion (TL-IVDE). However, their efficacy in decreasing gastrointestinal (GI) complications is unknown. Omeprazole does not decrease the frequency of GI complications compared to placebo in dogs treated surgically for acute TL-IVDE. Thirty-seven client-owned dogs undergoing hemilaminectomy for acute TL-IVDE. Randomized double-blinded placebo-controlled prospective clinical trial. Dogs received PO placebo or omeprazole at 1mg/kg q12h for 5 days during hospitalization. Development of GI signs (e.g., diarrhea, vomiting, regurgitation, hematochezia, melena) was recorded daily. Clinicopathologic testing performed during hospitalization and at 2 and 4-week re-evaluations included: fecal occult blood, PCV, blood urea nitrogen/creatinine ratio, fecal calprotectin, canine pancreatic lipase immunoreactivity and fecal alpha-1 proteinase inhibitor concentrations. Omeprazole and placebo groups were compared using chi-squared or Fisher's exact tests. Gastrointestinal signs developed in 10/20 (50%) dogs in the omeprazole group and in 7/17 (41%) dogs in the placebo group (P= .59). Diarrhea was common (8/20 omeprazole, 5/17 placebo), hematochezia was rare (1/20 omeprazole, 1/17 placebo); melena was not observed. Clinicopathologic evidence suggestive of bleeding was present in 9/20 dogs treated with omeprazole and in 11/17 dogs that received placebo (P= .23). Fecal occult blood positivity was more common in dogs with GI signs (P= .03). Canine pancreatic lipase immunoreactivity was higher during hospitalization compared to re-evaluations (P= .01). Short-term, prophylactic omeprazole treatment did not decrease clinically detectable GI complications in dogs with acute TL-IVDE.

Adequacy of Iodine Status and Associations with Gut Health: A Prospective Cohort Study among Infants in 8 Low- and Middle-Income Countries

BackgroundEnvironmental enteric dysfunction increases the likelihood of micronutrient deficiencies among infants, but few studies have assessed the potential impact of gut health on urinary iodine concentration (UIC) among this vulnerable group. ObjectivesWe describe the trends of iodine status among infants from 6 to 24 mo old and examine the associations between intestinal permeability, inflammation, and UIC from 6 to 15 mo of age. MethodsData from 1557 children enrolled in this birth cohort study conducted in 8 sites were included in these analyses. UIC was measured at 6, 15, and 24 mo of age by using the Sandell-Kolthoff technique. Gut inflammation and permeability were assessed using the concentrations of fecal neopterin (NEO), myeloperoxidase (MPO) and alpha-1–antitrypsin (AAT), and lactulose–mannitol ratio (LM). A multinomial regression analysis was used to assess the classified UIC (deficiency or excess). Linear mixed regression was used to test the effect of interactions among biomarkers on logUIC. ResultsAll studied populations had adequate (≥100 μg/L) to excess (≥371 μg/L) median UIC at 6 mo. Between 6 and 24 mo, 5 sites displayed a significant decline in the infant’s median UIC. However, median UIC remained within the optimal range. An increase of NEO and MPO concentrations by +1 unit in ln scale reduced the risk of low UIC by 0.87 (95% CI: 0.78–0.97) and 0.86 (95% CI: 0.77–0.95), respectively. AAT moderated the association between NEO and UIC (P < 0.0001). The shape of this association appears to be asymmetric and in a reverse J-shape, with a higher UIC observed at both lower NEO and AAT concentrations. ConclusionsExcess UIC was frequent at 6 mo and tended to normalize at 24 mo. Aspects of gut inflammation and increased permeability appear to reduce the prevalence of low UIC in children aged 6 to 15 mo. Programs addressing iodine-related health should consider the role of gut permeability in vulnerable individuals.

Effect of dietary β-glucan on intestinal microbial diversity and Salmonella vaccine immunogenicity and efficacy in pigs

Alternatives to antibiotics to improve animal performance, limit the negative impact of infectious disease, and/or reduce colonization with foodborne pathogens is a major focus of animal agricultural research. β-glucans, a generally-recognized-as-safe (GRAS) product derived from various sources, are used in swine and can serve as both a prebiotic and/or stimulant of the immune system given the expression of β-glucan receptors on immune cells. When supplied in the diet of nursery pigs, it is unclear how dietary additives, particularly those known to modulate immune status, impact immunogenicity and efficacy of mucosal-delivered vaccines. Salmonellosis is one of the most common bacterial foodborne infections in the United States, and consumption of contaminated pork is a major source of human infection. Reduction of foodborne Salmonella in pigs via vaccination is one strategy to reduce contamination risk and subsequently reduce human disease. We examined the ability of dietary β-glucan to modulate fecal microbial diversity, and immunogenicity and efficacy of a mucosally-delivered, live-attenuated Salmonella vaccine during the nursery period. While dietaryβ-glucan did modulate fecal alpha diversity, it did not alter the induction of peripheral Salmonella-specific IFN-γ secreting Tcells or Salmonella-specific IgA in oral fluids. In addition, vaccination reduced Salmonella enterica serovar Typhimurium fecal shedding and tissue colonization. Overall, addition of β-glucan to the nursery diet of pigs impacted the microbiota but did not alter mucosal vaccine immunogenicity and efficacy.

S2782 Successful Medical Management of a Patient With Severe Hypoalbuminemia due to Ulcerative Colitis

Introduction: Severe hypoalbuminemia (< 1gm/dL) is a rare complication of ulcerative colitis and may be both debilitating and refractory to therapy. Literature reports indicate that colectomy is curative and imply that it is the treatment of choice. We successfully treated such a patient medically. Case Description/Methods: This 40-year-old female was diagnosed with proctosigmoiditis in 2017, initially treated with oral mesalamine, then lost to care from 2018 through 2021. She presented in November 2021 with a disease flare and was shown to have pan-colitis. She was started on corticosteroids and began therapy with infliximab with initial symptomatic improvement. However, diarrhea continued, she developed increased symptoms plus anasarca during the steroid taper and was admitted. Serum albumin was 0.5 mg/dL. Inflammatory markers were elevated: C-reactive protein 103.8 mg/L and fecal calprotectin 1,126 ug/g. After infection was ruled out, colonoscopy was performed and showed extensive pseudopolyposis. Non-intestinal causes of protein loss were ruled out. Fecal alpha-1 antitrypsin levels were elevated before but not after an infliximab infusion (0.850 vs 0.110 mg/g, respectively). Despite receiving 10 mg/kg of infliximab every 6 weeks, her trough levels were undetectable and low levels of antibodies were detected. Intravenous albumin and diuretics provided some relief, but serum albumin concentration plateaued around 2.5 gm/dL. Mesalamine then was added to the regimen and the patient improved rapidly, with complete cessation of diarrhea, a rise in serum albumin concentration to 3.5 g/dL over 4 weeks, and clearance of the patient’s edema. Discussion: Severe hypoalbuminemia as a result of ulcerative colitis has previously been described and may lead to treatment failure and colectomy, even during treatment with biologic agents. Some cases are not due to intestinal protein losses such as in co-existing Menetriere’s disease or nephrotic syndrome. Elevated clearance rates of the biologic agents lead to subtherapeutic serum levels and antibody formation, promoting treatment failure. This case suggests that there may a role for adjunctive 5-ASA therapy. As part of the medications’ anti-inflammatory effects, they decrease enteric loss of infliximab and elevate its serum levels.

Discrete role for maternal stress and gut microbes in shaping maternal and offspring immunity

Psychosocial stress is prevalent during pregnancy, and is associated with immune dysfunction, both for the mother and the child. The gut microbiome has been implicated as a potential mechanism by which stress during pregnancy can impact both maternal and offspring immune function; however, the complex interplay between the gut microbiome and the immune system is not well-understood. Here, we leverage a model of antimicrobial-mediated gut microbiome reduction, in combination with a well-established model of maternal restraint stress, to investigate the independent effects of and interaction between maternal stress and the gut microbiome in shaping maternal and offspring immunity. First, we confirmed that the antimicrobial treatment reduced maternal gut bacterial load and altered fecal alpha and beta diversity, with a reduction in commensal microbes and an increase in the relative abundance of rare taxa. Prenatal stress also disrupted the gut microbiome, according to measures of both alpha and beta diversity. Furthermore, prenatal stress and antimicrobials independently induced systemic and gastrointestinal immune suppression in the dam with a concomitant increase in circulating corticosterone. While stress increased neutrophils in the maternal circulation, lymphoid cells and monocytes were not impacted by either stress or antimicrobial treatment. Although the fetal immune compartment was largely spared, stress increased circulating neutrophils and CD8 T cells, and antibiotics increased neutrophils and reduced T cells in the adult offspring. Altogether, these data indicate similar, but discrete, roles for maternal stress and gut microbes in influencing maternal and offspring immune function.

Plastic Bronchitis and Protein-Losing Enteropathy in the Fontan Patient: Evolving Understanding and Emerging Therapies.

Plastic bronchitis (PB) and protein-losing enteropathy (PLE) are rare but potentially devastating complications of the Fontan circulation. PB occurs in ∼4% of Fontan patients, typically presents within 2 to 3 years of Fontan completion with chronic cough, wheezing, fever, or acute asphyxiation, and is characterised by proteinaceous airway casts that are expectorated or found on bronchoscopy. PLE develops in 4% to 13% of patients, usually within 5 to 10 years post Fontan, and manifests with edema, ascites, hypoalbuminemia, lymphopenia, hypogammaglobulinemia, and elevated fecal alpha-1 antitrypsin 1. These disorders have similar pathophysiology involving disruption of the lymphatic system resulting from elevated central venous pressure combined with elevated lymphatic production and inflammation, resulting in lymphatic drainage into low-pressure circuits such as the airways (PB) and duodenum (PLE). Our understanding of these disorders has greatly improved over the past decade as a result of advances in imaging of the lymphatic system through magnetic resonance lymphangiography and early success with lymphatic interventions including lymphatic embolisation, thoracic duct embolisation, and percutaneous thoracic duct decompression. Both PB and PLE require a multidisciplinary approach that addresses and optimises residual hemodynamic lesions through catheter-based intervention, lowers central venous pressure through medical therapy, minimises symptoms, and targets abnormal lymphatic perfusion when symptoms persist. This review summarises the pathophysiology of these disorders and the current evidence base regarding management, proposes treatment algorithms, and identifies future research opportunities. Key considerations regarding the development of a lymphatic intervention program are also highlighted.

Resuscitation of very preterm infants with 30% vs. 50% oxygen: a randomized controlled trial

Background Preterm infants are susceptible to the damaging effects of hyperoxia which may lead to bronchopulmonary dysplasia (BPD) and intestinal damage. Hyperoxia also affects intestinal microbiota. The optimal initial FiO2 for the resuscitation of premature infants is unknown.&#x0D; Objective To determine the effect of different initial oxygen concentrations on BPD, oxidative stress markers, damage to the gastrointestinal mucosa, and the intestinal microbiome.&#x0D; Methods We conducted an unblinded, randomized controlled clinical trial in premature infants requiring supplemental oxygen in the first minutes of life. Infants started at an FiO2 of either 30% (low) or 50% (moderate), which was adjusted to achieve target oxygen saturations (SpO2) of 88-92% by 10 minutes of life using pulse oximetry. The primary outcome was incidence of BPD. Secondary outcomes included markers of oxidative stress [oxidized glutathione (GSH)/reduced glutathione (GSSG) ratio and malondialdehyde (MDA)], intestinal integrity indicated by fecal alpha-1 antitrypsin (AAT), and intestinal microbiota on fecal examination.&#x0D; Results Eighty-four infants were recruited. There was no significant difference in rates of BPD between the 30% FiO2 and 50% FiO2 groups (42.8% vs. 40.5%, respectively). Nor were there significant differences in GSH/GSSG ratios, MDA concentrations, fecal AAT levels, or changes in facultative anaerobic and anaerobic microbiota between groups.&#x0D; Conclusion In premature infants resuscitated using low vs. moderate initial FiO2 levels, we find no significant differences in BPD incidence, markers of oxidative stress, intestinal mucosa integrity, or intestinal microbiota.

The establishment of the gut microbiota in 1-year-aged infants: from birth to family food

PurposeWith the aim of characterizing the gastrointestinal (GI) microbiota and contextually determine how different prenatal, perinatal, and postnatal factors affected its composition in early childhood, infants were enrolled in a longitudinal-prospective study named “A.MA.MI.” (Alimentazione MAmma e bambino nei primi MIlle giorni; NCT04122612, October 2019).MethodsForty-five fecal samples were collected at 12 months of infants’ age, identified as the 3rd follow-up (T3). The evaluated variables were pre-gestational weight and weight gain during pregnancy, delivery mode, feeding, timing of weaning, and presence/absence of older siblings. Fecal alpha and beta-diversities were analyzed. Noteworthy, to determine the impact of the influencing factors, multivariate analyses were conducted.ResultsAt T3, all prenatal and perinatal variables did not result to be significant whereas, among the postnatal variables, type of milk-feeding and weaning showed the greatest contribution in shaping the microbiota. Although aged 1 year, infants exclusively breastfed until 6 months were mainly colonized by Lactobacillaceae and Enterobacteriaceae. Differently, Bacteroidaceae characterized the microbiota of infants that were never breastfed in an exclusive way. Moreover, although an early introduction of solid foods determined higher values of Faith’s PD, high abundances of Ruminococcaceae and Faecalibacterium mainly associated with infants weaned after the 4th month of age.ConclusionThe microbial colonization during the first year of life is likely affected by a simultaneous effect of multiple variables playing a significant role at different times. Therefore, these data contribute to add evidence concerning the complex multifactorial interaction between GI microbiota and various stimuli affecting infants during the early stages of life.

Gut microbiome and metabolome in a non-human primate model of chronic excessive alcohol drinking

A relationship between the gut microbiome and alcohol use disorder has been suggested. Excessive alcohol use produces changes in the fecal microbiome and metabolome in both rodents and humans. Yet, these changes can be observed only in a subgroup of the studied populations, and reversal does not always occur after abstinence. We aimed to analyze fecal microbial composition and function in a translationally relevant baboon model of chronic heavy drinking that also meets binge criteria (drinking too much, too fast, and too often), i.e., alcohol ~1 g/kg and blood alcohol levels (BALs) ≥ 0.08 g/dL in a 2-hour period, daily, for years. We compared three groups of male baboons (Papio anubis): L = Long-term alcohol drinking group (12.1 years); S = Short-term alcohol drinking group (2.7 years); and C = Control group, drinking a non-alcoholic reinforcer (Tang®) (8.2 years). Fecal collection took place during 3 days of Drinking (D), followed by a short period (3 days) of Abstinence (A). Fecal microbial alpha- and beta-diversity were significantly lower in L vs. S and C (p’s < 0.05). Members of the commensal families Lachnospiraceae and Prevotellaceae showed a relative decrease, whereas the opportunistic pathogen Streptococcus genus showed a relative increase in L vs. S and C (p’s < 0.05). Microbiota-related metabolites of aromatic amino acids, tricarboxylic acid cycle, and pentose increased in L vs. S and C (FDR-corrected p < 0.01), with the latter two suggesting high energy metabolism and enhanced glycolysis in the gut lumen in response to alcohol. Consistent with the long-term alcohol exposure, mucosal damage and oxidative stress markers (N-acetylated amino acids, 2-hydroxybutyrate, and metabolites of the methionine cycle) increased in L vs. S and C (FDR-corrected p < 0.01). Overall, S showed few differences vs. C, possibly due to the long-term, chronic alcohol exposure needed to alter the normal gut microbiota. In the three groups, the fecal microbiome barely differed between conditions D and A, whereas the metabolome shifted in the transition from condition D to A. In conclusion, changes in the fecal microbiome and metabolome occur after significant long-term excessive drinking and are only partially affected by acute forced abstinence from alcohol. These results provide novel information on the relationship between the fecal microbiome and metabolome in a controlled experimental setting and using a unique non-human primate model of chronic excessive alcohol drinking.

Nutrition As a Predictor of Microbiome Injury in Allo-HCT

Nutrition As a Predictor of Microbiome Injury in Allo-HCT

Weak Precipitin Ring from A Fecal Specimen with Markedly Elevated Alpha-1 Antitrypsin Level Measured by Radial Immunodiffusion

Abstract Radial immunodiffusion (RID) is a classic methodology for antigen quantification that relies on the development of a distinct precipitin ring from precipitated antigen-antibody complex. As the precipitin ring grows, the precipitate at the inner edge of the ring constantly dissolves due to excess antigen flooding from the point of application, while new precipitate forms at the leading edge of the ring. RID plates with anti-human alpha-1-antitrypsin are prepared in our lab to measure fecal alpha-1 antitrypsin (A1AT) to aid in the diagnosis and monitoring of Protein Losing Enteropathy (PLE). The procedure has routinely produced precipitin rings with small radii and distinct edges after incubating at room temperature for 48 hours. Unexpectedly, a fecal specimen from a patient produced an extremely weak and large precipitin ring that could have been easily overlooked. Dilution studies confirmed a highly elevated A1AT level of 67 mg/g dry stool. The very weak and large precipitin ring was reproduced with a spiked specimen with similar A1AT concentration and kept expanding for several days until a distinct ring was formed eventually. Our data highlights a rare example of high-dose hook effect in RID and calls for meticulous attention and caution when reading and interpreting gel-based immunoassays with unexpected markedly elevated results to avoid additional confirmatory testing. In these cases, we recommend repeat testing with diluted specimens.

88 Effects of Saccharomyces cerevisiae fermentation product on microbiota populations of dogs subjected to travel stress

Abstract Previously, a Saccharomyces cerevisiae fermentation product (SCFP) positively altered fecal microbiota, fecal metabolites, and function of circulating immune cells in adult dogs. The objective of this study was to determine the fecal characteristics, microbiota, and metabolites of dogs subjected to travel stress. All procedures were approved by the Four Rivers Kennel IACUC prior to experimentation. Thirty-six adult dogs (mean age: 7.1 y; mean BCS: 4.9) were used. Dogs were randomly assigned to control or SCFP-supplemented (250 mg/day) diets and fed for a few months prior to a travel stress challenge. Fresh fecal samples were collected for the measurement of fecal characteristics, microbiota, and metabolites before and after travel stress. Fecal microbiota data were evaluated using QIIME2. All other data were analyzed using the Mixed Models procedure of SAS, with P &amp;lt; 0.05 considered statistically significant. There were no differences between treatments on fecal characteristics, metabolites, and bacterial alpha and beta diversity measures. However, fecal Turicibacter increased in dogs fed SCFP (0.8% to 1.2%, P = 0.03), but decreased in dogs fed control (1.2% to 0.7%, P = 0.03). Fecal Prevotella (5% to 7%, P = 0.004), Oscillospira (0.07% to 0.1%, P = 0.004) and Sutterella (3% to 4%, P = 0.01) increased after travel stress in dogs fed control. In contrast, fecal Clostridium (11% to 15%, P = 0.01), Faecalibacterium (6% to 8%, P = 0.003), and Allobaculum (1% to 2%, P = 0.02) increased and fecal Phascolarctobacterium (1.4% to 1.1%, P = 0.001) decreased after travel stress in dogs fed SCFP. Our data demonstrate that both travel stress and SCFP alter fecal microbiota in dogs.

Gastrointestinal protein loss in children with portal hypertension.

Portal hypertension increases pressure in lymphatic ducts, which may lead to gastrointestinal(GI) protein loss. Reports have shown that adults with portal hypertension had resolution of protein-losing enteropathy after transplantation; but studies in children are very limited. We therefore aimed to evaluate GI protein loss in children with portal hypertension and defined changes after liver transplantation. Children aged 3months to 18years with portal hypertension and the age-matched healthy controls were enrolled during August 2018 to September 2019. Random fecal alpha-1 antitrypsin measurements were obtained at the initial visit, 3months later, 1week before, and 3months after liver transplantation (if applicable). One or more positive test (> 0.795mg/dL) was interpreted as a positive result. We enrolled 76 children (n = 38 in each group) with a median age of 15.5months (interquartile range [IQR], 11.2-41.7), female 51%, and 92% with biliary atresia in the portal hypertension group. We noted GI protein loss in 4/38 children (10.5%) with portal hypertension, while none in the controls (p = 0.11). We found no significant differences on the markers of severity of liver disease and serum albumin between patients with vs. the ones without GI protein loss (p > 0.05). After liver transplantation, 2/4 patients with GI protein loss had undetectable loss. We found that, in a small group of children, 10.5% with portal hypertension had notable GI protein loss without significant relationships with the severity of liver disease.