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1.
Ground Water ; 62(5): 761-777, 2024.
Article in English | MEDLINE | ID: mdl-38553951

ABSTRACT

Recharge to and flow within the Columbia River Basalt Group (CRBG) groundwater flow system of northeastern Oregon were characterized using isotopic, gas, and age-tracer samples from wells completed in basalt, springs, and stream base flow. Most groundwater samples were late-Pleistocene to early-Holocene; median age of well samples was 11,100 years. The relation between mean groundwater age and completed well depth across the eastern portion of the study area was similar despite differences in precipitation, topographic position, incision, thickness of the sedimentary overburden, and CRBG geologic unit. However, the lateral continuity in groundwater age was disrupted across large regional fault zones indicating these structures are substantial impediments to groundwater flow from the high-precipitation uplands to adjacent lower-precipitation and lower-elevation portions of the study area. Recharge rates calculated from the age-depth relations were <3 mm/yr and independent of the modern precipitation gradient across the study area. The age-constrained recharge rates to the CRBG groundwater system are considerably smaller than previously published estimates and highlight the uncertainty of prevailing models used to estimate recharge to the CRBG groundwater system across the Columbia Plateau in Oregon and Washington. Age tracer and isotopic evidence indicate recharge to the CRBG groundwater system is an exceedingly slow and localized process.


Subject(s)
Groundwater , Rivers , Water Movements , Oregon , Environmental Monitoring/methods
2.
Pediatr Surg Int ; 40(1): 35, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38216767

ABSTRACT

PURPOSE: Necrotizing enterocolitis (NEC) is a severe intestinal disease primarily affecting premature infants, marked by impaired epithelial regeneration. Breastfed infants are less susceptible to NEC than formula-fed ones, and human milk oligosaccharides (HMO) found in breast milk have prebiotic properties that can protect against NEC. However, it is unclear how HMOs influence intestinal epithelium regeneration in relation to the gut microbiota. METHODS: Broad-spectrum antibiotics were administered to pregnant dams to reduce the microbiota in offspring. NEC was induced through administration of hyperosmolar formula, lipopolysaccharide, and hypoxia from postnatal days (p) 5-9. Intestinal epithelial organoids were derived from p9 mice. HMOs were isolated from human donor breast milk and then solubilized in the formula for each feed or culture media for organoids. RESULTS: HMOs did not alter the microbiota profile in the presence of a normal or reduced microbiota. In the reduced microbiota, HMO treatment decreased NEC intestinal injury, and increased proliferation and stem cell activity. Additionally, in the complete absence of the microbiota, HMOs stimulated intestinal organoid growth. CONCLUSION: This study demonstrates that HMOs promoted intestinal epithelial regeneration independent of the gut microbiota. These findings provide further insight into the various benefits HMOs may have in the protection against NEC.


Subject(s)
Enterocolitis, Necrotizing , Infant, Newborn, Diseases , Microbiota , Infant , Female , Pregnancy , Infant, Newborn , Animals , Humans , Mice , Milk, Human , Enterocolitis, Necrotizing/prevention & control , Intestinal Mucosa , Oligosaccharides/pharmacology , Regeneration
3.
Front Immunol ; 14: 1043680, 2023.
Article in English | MEDLINE | ID: mdl-36969170

ABSTRACT

Zetomipzomib (KZR-616) is a selective inhibitor of the immunoproteasome currently undergoing clinical investigation in autoimmune disorders. Here, we characterized KZR-616 in vitro and in vivo using multiplexed cytokine analysis, lymphocyte activation and differentiation, and differential gene expression analysis. KZR-616 blocked production of >30 pro-inflammatory cytokines in human peripheral blood mononuclear cells (PBMCs), polarization of T helper (Th) cells, and formation of plasmablasts. In the NZB/W F1 mouse model of lupus nephritis (LN), KZR-616 treatment resulted in complete resolution of proteinuria that was maintained at least 8 weeks after the cessation of dosing and was mediated in part by alterations in T and B cell activation, including reduced numbers of short and long-lived plasma cells. Gene expression analysis of human PBMCs and tissues from diseased mice revealed a consistent and broad response focused on inhibition of T, B, and plasma cell function and the Type I interferon pathway and promotion of hematopoietic cell lineages and tissue remodeling. In healthy volunteers, KZR-616 administration resulted in selective inhibition of the immunoproteasome and blockade of cytokine production following ex vivo stimulation. These data support the ongoing development of KZR-616 in autoimmune disorders such as systemic lupus erythematosus (SLE)/LN.


Subject(s)
Leukocytes, Mononuclear , Lupus Nephritis , Humans , Animals , Mice , Leukocytes, Mononuclear/metabolism , Cytokines/metabolism , Immunity
4.
Cardiovasc Res ; 119(4): 1030-1045, 2023 05 02.
Article in English | MEDLINE | ID: mdl-36464772

ABSTRACT

AIMS: The loss of vascular wall cells in allotransplanted arteries is the initial event leading to transplant arteriosclerosis (TA) and ensuing loss of allograft function. Pharmacological agents able to prevent TA are currently lacking. We previously showed that selective inhibition of the immunoproteasome prevented the chronic rejection of renal allografts. However, the role and mechanisms of selective inhibition of a single immunoproteasome subunit to prevent immune-mediated vascular allograft rejection and TA is not clear. METHODS AND RESULTS: The effect and potential mechanism of combined or individual inhibition of peptidolytically active immunoproteasome LMP7 (ß5i) and LMP2 (ß1i) subunits on immune rejection-mediated TA was investigated using the epoxyketone inhibitor ONX 0914, and the recently developed LMP7-selective inhibitor KZR-329 and LMP2-selective inhibitor KZR-504 in a rat aorta transplantation model. We find that co-inhibition of LMP7 and LMP2 in allogeneic recipients significantly suppressed T-cell activation and function by expressing inhibitory surface markers and then activating inhibitory signals. Moreover, co-inhibition of LMP7 and LMP2 substantially reduced the number of immunoglobulin G-secreting cells and plasma cells and production of alloantibodies through activating the unfolded protein response and incapacitating the survival niche of plasma cells in the bone marrow. Consequentially, the accumulation of inflammatory cytokines, complement, and antibodies is reduced and the apoptosis of vascular wall cells decreased in aortic allografts via LMP7 and LMP2 co-inhibition with ONX 0914 treatment or combined KZR-329 and KZR-504 treatment. However, neither individual inhibition of LMP7 by KZR-329 nor individual inhibition of LMP2 by KZR-504 showed suppression of immune rejection and TA. CONCLUSIONS: We define a critical role of LMP7 and LMP2 in TA and strongly propose co-inhibition of both immunoproteasome subunits as promising therapeutic approach to suppress TA and allograft rejection.


Subject(s)
Arteriosclerosis , Kidney , Rats , Animals , Kidney/metabolism , Cytokines/metabolism , Graft Rejection/prevention & control
5.
Front Cell Infect Microbiol ; 12: 883163, 2022.
Article in English | MEDLINE | ID: mdl-35774405

ABSTRACT

Compositional analysis of the intestinal microbiome in pre-schoolers is understudied. Effects of probiotics on the gut microbiota were evaluated in children under 4-years-old presenting to an emergency department with acute gastroenteritis. Included were 70 study participants (n=32 placebo, n=38 probiotics) with stool specimens at baseline (day 0), day 5, and after a washout period (day 28). Microbiota composition and deduced functions were profiled using 16S ribosomal RNA sequencing and predictive metagenomics, respectively. Probiotics were detected at day 5 of administration but otherwise had no discernable effects, whereas detection of bacterial infection (P<0.001) and participant age (P<0.001) had the largest effects on microbiota composition, microbial diversity, and deduced bacterial functions. Participants under 1 year had lower bacterial diversity than older aged pre-schoolers; compositional changes of individual bacterial taxa were associated with maturation of the gut microbiota. Advances in age were associated with differences in gut microbiota composition and deduced microbial functions, which have the potential to impact health later in life. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT01853124.


Subject(s)
Gastroenteritis , Gastrointestinal Microbiome , Microbiota , Probiotics , Child , Child, Preschool , Feces/microbiology , Gastroenteritis/drug therapy , Humans , Intestines , Probiotics/therapeutic use , RNA, Ribosomal, 16S/genetics
6.
J Stud Alcohol Drugs ; 83(3): 439-449, 2022 05.
Article in English | MEDLINE | ID: mdl-35590185

ABSTRACT

OBJECTIVE: Previous research suggests that exposure to alcohol primes (i.e., stimuli associated with alcohol) affects drinkers' perceptions and behaviors. The present study investigated the effects of an environmental alcohol prime (being in a simulated bar setting) and a safe sex message prime (a public health safe sex message) on sexually active alcohol drinkers. METHOD: Participants (n = 80) were assigned to one of four conditions according to priming allocation and engaged in a simulated video chat with a potential partner. They reported their sex-related self-perceptions and perceptions of a potential partner upon procedural completion. RESULTS: The alcohol-related environmental prime led participants to rate their potential partner as being significantly less inhibited and more sexual. The safe sex message significantly reduced reported sex-related self-perceptions and perceptions of their partners' disinhibition. There was a significant effect of primes on participants' perceptions of their partner's friendliness--participants exposed to either or both prime(s) perceived their partner as being friendlier than participants exposed to no prime. CONCLUSIONS: Results suggest that environmental alcohol primes may strengthen sexually active drinkers' perceptions of a potential partner's disinhibition and sexuality even before alcohol consumption begins, and that a safe sex message may moderate these effects. The presence of safe sex messages in alcohol-related environments may positively influence sexual risk decision making among sexually active drinkers.


Subject(s)
Safe Sex , Sexual Partners , Alcohol Drinking/epidemiology , Ethanol , Humans , Sexual Behavior
7.
Nutrients ; 14(5)2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35267989

ABSTRACT

BACKGROUND: Human milk oligosaccharides are complex, non-digestible carbohydrates that directly interact with intestinal epithelial cells to alter barrier function and host inflammation. Oligosaccharide composition varies widely between individual mothers, but it is unclear if this inter-individual variation has any impact on intestinal epithelial barrier function and gut inflammation. METHODS: Human milk oligosaccharides were extracted from the mature human milk of four individual donors. Using an in vitro model of intestinal injury, the effects of the oligosaccharides on the intestinal epithelial barrier and select innate and adaptive immune functions were assessed. RESULTS: Individual oligosaccharide compositions shared comparable effects on increasing transepithelial electrical resistance and reducing the macromolecular permeability of polarized (Caco-2Bbe1) monolayers but exerted distinct effects on the localization of the intercellular tight junction protein zona occludins-1 in response to injury induced by a human enteric bacterial pathogen Escherichia coli, serotype O157:H7. Immunoblots showed the differential effects of oligosaccharide compositions in reducing host chemokine interleukin 8 expression and inhibiting of p38 MAP kinase activation. CONCLUSIONS: These results provide evidence of both shared and distinct effects on the host intestinal epithelial function that are attributable to inter-individual differences in the composition of human milk oligosaccharides.


Subject(s)
Intestinal Mucosa , Milk, Human , Humans , Inflammation/metabolism , Intestinal Mucosa/metabolism , Oligosaccharides/pharmacology , Pilot Projects
8.
Pediatr Res ; 91(1): 101-106, 2022 01.
Article in English | MEDLINE | ID: mdl-34561550

ABSTRACT

BACKGROUND: Stem cell therapy has been proven to rescue intestinal injury and stimulate intestinal regeneration in necrotizing enterocolitis (NEC). Specifically, stem cells derived from amniotic fluid (AFSCs) and mesenchymal stem cells (MSCs) derived from bone marrow have shown promising results in the treatment of experimental NEC. This study aims to examine the effects of AFSCs and MSCs on the prevention of intestinal injury during experimental NEC. METHODS: Supernatants from AFSC and MSC cultures were collected to perform proteomic analysis. Prior to NEC induction, mice received intraperitoneal injections of phosphate-buffered saline (PBS), 2 × 106 AFSCs, or 2 × 106 MSCs. RESULTS: We found that AFSCs grew faster than MSCs. Proteomic analysis indicated that AFSCs are primarily involved in cell development and growth, while MSCs are involved in immune regulation. Administering AFSCs before NEC induction decreased NEC severity and mucosal inflammation. Intestinal proliferation and endogenous stem cell activation were increased after AFSC administration. However, administering MSCs before NEC induction had no beneficial effects. CONCLUSIONS: This study demonstrated that AFSCs and MSCs have different protein release profiles. AFSCs can potentially be used as a preventative strategy for neonates at risk of NEC, while MSCs cannot be used. IMPACT: AFSCs and MSCs have distinct protein secretory profiles, and AFSCs are primarily involved in cell development and growth, while MSCs are involved in immune regulation. AFSCs are unique in transiently enhancing healthy intestinal epithelial cell growth, which offers protection against the development of experimental NEC. The prevention of NEC via the administration of AFSCs should be evaluated in infants at great risk of developing NEC or in infants with early signs of NEC.


Subject(s)
Amniotic Fluid/cytology , Stem Cell Transplantation , Animals , Enterocolitis, Necrotizing , Humans , Infant, Newborn , Mice
9.
Mol Nutr Food Res ; 66(4): e2100893, 2022 02.
Article in English | MEDLINE | ID: mdl-34921749

ABSTRACT

SCOPE: Necrotizing enterocolitis (NEC) is a devastating gastrointestinal emergency affecting preterm infants. Breastmilk protects against NEC, partly due to human milk oligosaccharides (HMOs). HMO compositions are highly diverse, and it is unclear if anti-NEC properties are specific to carbohydrate motifs. Here, this study compares intestinal epithelial transcriptomes of five synthetic HMOs (sHMOs) and examines structure-function relationships of HMOs on intestinal signaling. METHODS AND RESULTS: This study interrogates the transcriptome of Caco-2Bbe1 cells in response to five synthetic HMOs (sHMOs) using RNA sequencing: 2'-fucosyllactose (2'-FL), 3-fucosyllactose (3FL), 6'-siallyllactose (6'-SL), lacto-N-tetraose (LNT), lacto-N-neotetraose (LNnT). Protection against intestinal barrier dysfunction and inflammation occurred in an HMO-dependent manner. Each sHMO exerts a unique set of host transcriptome changes and modulated unique signaling pathways. There is clustering between HMOs bearing similar side chains, with little overlap in gene regulation which is shared by all sHMOs. Interestingly, most sHMOs protect pups against NEC, exerting divergent mechanisms on intestinal cell morphology and inflammation. CONCLUSIONS: These results demonstrate that while structurally distinct HMOs impact intestinal physiology, their mechanisms of action differ. This finding establishes the first structure-function relationship of HMOs in the context of intestinal cell signaling responses and offers a functional framework by which to screen and design HMO-like compounds.


Subject(s)
Enterocolitis, Necrotizing , Milk, Human , Animals , Caco-2 Cells , Disease Models, Animal , Enterocolitis, Necrotizing/prevention & control , Humans , Infant , Infant, Newborn , Infant, Premature , Mice , Milk, Human/chemistry , Oligosaccharides/chemistry , Structure-Activity Relationship , Transcriptome
10.
Water Resour Res ; 57(7)2021 Jul 01.
Article in English | MEDLINE | ID: mdl-34349298

ABSTRACT

Rising global temperatures are expected to decrease the precipitation amount that falls as snow, causing greater risk of water scarcity, groundwater overdraft, and fire in areas that rely on mountain snowpack for their water supply. Streamflow in large river basins varies with the amount, timing, and type of precipitation, evapotranspiration, and drainage properties of watersheds; however, these controls vary in time and space making it difficult to identify the areas contributing most to flow and when. In this study, we separate the evaporative influences from source values of water isotopes from the Snake River Basin in the western United States (US) to relate source area to flow dynamics. We developed isoscapes (δ2H and δ18O) for the basin and found that isotopic composition of surface water in small watersheds is primarily controlled by longitude, latitude, and elevation. To examine temporal variability in source contributions to flow, we present a six-year record of Snake River water isotopes from King Hill, Idaho after removing evaporative influences. During periods of low flow, source water values were isotopically lighter indicating a larger contribution to flow from surface waters in the highest elevation, eastern portion of the basin. River evaporation increases were evident during summer likely reflecting climate, changing water availability, and management strategies within the basin. Our findings present a potential tool for identifying critical portions of basins contributing to river flow as climate fluctuations alter flow dynamics. This tool can be applied in other continental-interior basins where evaporation may obscure source water isotopic signatures.

11.
Am J Clin Nutr ; 113(4): 905-914, 2021 04 06.
Article in English | MEDLINE | ID: mdl-34269370

ABSTRACT

BACKGROUND: We previously conducted the Probiotic Regimen for Outpatient Gastroenteritis Utility of Treatment (PROGUT) study, which identified no improvements in children with acute gastroenteritis (AGE) administered a probiotic. However, the aforementioned study did not evaluate immunomodulatory benefits. OBJECTIVES: The object of this study was to determine if stool secretory immunoglobulin A (sIgA) concentrations in children with AGE increase more among participants administered a Lactobacillus rhamnosus/helveticus probiotic compared with those administered placebo. METHODS: This a priori planned multicenter, randomized, double-blinded, placebo-controlled ancillary study enrolled children presenting for emergency care who received a 5-d probiotic or placebo course. Participants submitted stool specimens on days 0, 5, and 28. The primary endpoint was the change in stool sIgA concentrations on day 5 compared with baseline. RESULTS: A total of 133 (n = 66 probiotic, 67 placebo) of 886 PROGUT participants (15.0%) provided all 3 specimens. Median stool sIgA concentrations did not differ between the probiotic and placebo groups at any of the study time points: day 0 median (IQR): 1999 (768, 4071) compared with 2198 (702, 5278) (P = 0.27, Cohen's d = 0.17); day 5: 2505 (1111, 5310) compared with 3207 (982, 7080) (P = 0.19, Cohen's d = 0.16); and day 28: 1377 (697, 2248) compared with 1779 (660, 3977) (P = 0.27, Cohen's d = 0.19), respectively. When comparing measured sIgA concentrations between days 0 and 5, we found no treatment allocation effects [ß: -0.24 (-0.65, 0.18); P = 0.26] or interaction between treatment and specimen collection day [ß: -0.003 (-0.09, 0.09); P = 0.95]. Although stool sIgA decreased between day 5 and day 28 within both groups (P < 0.001), there were no differences between the probiotic and placebo groups in the median changes in sIgA concentrations when comparing day 0 to day 5 median (IQR) [500 (-1135, 2362) compared with 362 (-1122, 4256); P = 0.77, Cohen's d = 0.075] and day 5 to day 28 [-1035 (-3130, 499) compared with -1260 (-4437, 843); P = 0.70, Cohen's d = 0.067], respectively. CONCLUSIONS: We found no effect of an L. rhamnosus/helveticus probiotic, relative to placebo, on stool IgA concentrations. This trial was registered at clinicaltrials.gov as NCT01853124.


Subject(s)
Feces/microbiology , Gastroenteritis/therapy , Immunoglobulin A, Secretory , Immunomodulation , Lacticaseibacillus rhamnosus/immunology , Lactobacillus helveticus/immunology , Probiotics/therapeutic use , Acute Disease/therapy , Emergency Medical Services , Female , Gastroenteritis/microbiology , Humans , Infant , Male
12.
Drug Metab Dispos ; 49(9): 810-821, 2021 09.
Article in English | MEDLINE | ID: mdl-34234005

ABSTRACT

KZR-616 is an irreversible tripeptide epoxyketone-based selective inhibitor of the human immunoproteasome. Inhibition of the immunoproteasome results in anti-inflammatory activity in vitro and based on promising therapeutic activity in animal models of rheumatoid arthritis and systemic lupus erythematosus KZR-616 is being developed for potential treatment of multiple autoimmune and inflammatory diseases. The presence of a ketoepoxide pharmacophore presents unique challenges in the study of drug metabolism during lead optimization and clinical candidate profiling. This study presents a thorough and systematic in vitro and cell-based enzymatic metabolism and kinetic investigation to identify the major enzymes involved in the metabolism and elimination of KZR-616. Upon exposure to liver microsomes in the absence of NADPH, KZR-616 and its analogs were converted to their inactive diol derivatives with varying degrees of stability. Diol formation was also shown to be the major metabolite in pharmacokinetic studies in monkeys and correlated with in vitro stability results for individual compounds. Further study in intact hepatocytes revealed that KZR-616 metabolism was sensitive to an inhibitor of microsomal epoxide hydrolase (mEH) but not inhibitors of cytochrome P450 (P450) or soluble epoxide hydrolase (sEH). Primary human hepatocytes were determined to be the most robust source of mEH activity for study in vitro. These findings also suggest that the exposure of KZR-616 in vivo is unlikely to be affected by coadministration of inhibitors or inducers of P450 and sEH. SIGNIFICANCE STATEMENT: This work presents a thorough and systematic investigation of metabolism and kinetics of KZR-616 and related analogs in in vitro and cell-based enzymatic systems. Information gained could be useful in assessing novel covalent proteasome inhibitors during lead compound optimization. These studies also demonstrate a robust source in vitro test system that correlated with in vivo pharmacokinetics for KZR-616 and two additional tripeptide epoxyketones.


Subject(s)
Cysteine Endopeptidases/immunology , Cytochrome P-450 Enzyme System/metabolism , Epoxide Hydrolases/metabolism , Morpholines/pharmacology , Proteasome Endopeptidase Complex/immunology , Proteins/immunology , Animals , Autoimmune Diseases/drug therapy , Cells, Cultured , Cysteine Endopeptidases/metabolism , Epoxide Hydrolases/immunology , Hepatocytes/metabolism , Humans , Inactivation, Metabolic , Inflammation/drug therapy , Macaca fascicularis , Proteasome Inhibitors/pharmacology
13.
Mol Nutr Food Res ; 64(21): e2000519, 2020 11.
Article in English | MEDLINE | ID: mdl-32926533

ABSTRACT

SCOPE: Necrotizing enterocolitis (NEC) is a devastating gastrointestinal emergency and currently the leading cause of mortality in preterm infants. Recent studies show that human milk oligosaccharides (HMOs) reduce the frequency and incidence of NEC; however, the molecular mechanisms for their protection are largely unexplored. METHODS AND RESULTS: To address this gap, a genome-wide profiling of the intestinal epithelial transcriptome in response to HMOs using RNA-sequencing is performed. It is found that HMOs alter the host transcriptome in 225 unique target genes pertaining to cell proliferation and differentiation, including upregulation of stem cell differentiation marker HMGCS2. To validate these results, differentiation in Caco-2Bbe1 (Caco-2) intestinal cells is verified by Alcian Blue staining and transepithelial electrical resistance (TER) recordings. Furthermore, an in vivo model of NEC is also employed whereby neonatal pups are gavage fed HMOs. Interestingly, HMOs-fed pups show enhanced cell MUC2 differentiation and HMGCS2 expression. CONCLUSIONS: These findings demonstrate HMOs protect against NEC in part by altering the differentiation of the crypt-villus axis. In addition, this study suggests that pooled HMOs directly induce a series of biological processes, which provide mechanistic insights to how HMOs protect the host intestine.


Subject(s)
Enterocolitis, Necrotizing/pathology , Enterocolitis, Necrotizing/prevention & control , Milk, Human/chemistry , Oligosaccharides/pharmacology , Animals , Caco-2 Cells , Cell Cycle/drug effects , Cell Cycle/genetics , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Dogs , Enterocolitis, Necrotizing/genetics , Female , Gene Expression Profiling , Humans , Hydroxymethylglutaryl-CoA Synthase/metabolism , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism , Madin Darby Canine Kidney Cells , Male , Mice, Inbred C57BL , Peroxisome Proliferator-Activated Receptors/metabolism , Signal Transduction/drug effects , Signal Transduction/genetics , TOR Serine-Threonine Kinases/metabolism
14.
Cell Death Dis ; 11(9): 750, 2020 09 14.
Article in English | MEDLINE | ID: mdl-32929076

ABSTRACT

Necrotizing enterocolitis (NEC) is a devastating intestinal disease primarily affecting preterm neonates and causing high morbidity, high mortality, and huge costs for the family and society. The treatment and the outcome of the disease have not changed in recent decades. Emerging evidence has shown that stimulating the Wnt/ß-catenin pathway and enhancing intestinal regeneration are beneficial in experimental NEC, and that they could potentially be used as a novel treatment. Amniotic fluid stem cells (AFSC) and AFSC-derived extracellular vesicles (EV) can be used to improve intestinal injury in experimental NEC. However, the mechanisms by which they affect the Wnt/ß-catenin pathway and intestinal regeneration are unknown. In our current study, we demonstrated that AFSC and EV attenuate NEC intestinal injury by activating the Wnt signaling pathway. AFSC and EV stimulate intestinal recovery from NEC by increasing cellular proliferation, reducing inflammation and ultimately regenerating a normal intestinal epithelium. EV administration has a rescuing effect on intestinal injury when given during NEC induction; however, it failed to prevent injury when given prior to NEC induction. AFSC-derived EV administration is thus a potential emergent novel treatment strategy for NEC.


Subject(s)
Enterocolitis, Necrotizing/genetics , Extracellular Vesicles/metabolism , Intestines/injuries , Wnt Signaling Pathway/genetics , Animals , Disease Models, Animal , Humans , Mice , Rats
15.
Front Nutr ; 7: 83, 2020.
Article in English | MEDLINE | ID: mdl-32582756

ABSTRACT

Purpose: Inflammatory bowel disease (IBD) refers to a spectrum of autoimmune diseases, which result in chronic intestinal inflammation. Previous findings suggest a role for diet, nutrition and dysbiosis of the gut microbiota in both the development and progression of the condition. Vitamin B12 is a key cofactor of methionine synthase and is produced solely by microbes. Previous work links increased levels of homocysteine, a substrate of methionine synthase, MetH, to IBD indicating a potential role for vitamin B12 deficiency in intestinal injury and inflammation. This study assessed the role of vitamin B12 in shaping the gut microbiota and determining responses to intestinal injury using a reproducible murine model of colitis. Methods: The effects of vitamin B12 supplementation and deficiency were assessed in vivo; 3-week-old post-weanling C57Bl/6 mice were divided into three dietary treatment groups: (1) sufficient vitamin B12 (50 mg/Kg), (2) deficient vitamin B12 (0 mg/Kg) and (3) supplemented vitamin B12 (200 mg/Kg) for a period of 4 weeks. Intestinal injury was induced with 2% dextran sodium sulphate (DSS) via drinking water for 5 days. The impact of varying levels of dietary vitamin B12 on gut microbiota composition was assessed using 16S rRNA gene sequencing from fecal samples collected at day 0 and day 28 of the dietary intervention, and 7 days following induction of colitis on day 38, when blood and colonic tissues were also collected. Results: No significant alterations were found in the gut microbiota composition of disease-free animals in response to dietary interventions. By contrast, after DSS-induced colitis, >30 genera were significantly altered in vitamin B12 deficient mice. Altered B12 levels produced no significant effect on composite disease-activity scores; however, administration of a B12 deficient diet resulted in reduced DSS-induced epithelial tissue damage. Conclusions: Vitamin B12 supplementation does not alter the gut microbiota composition under healthy conditions, but does contribute to differential microbial responses and intestinal dysbiosis following the induction of experimental colitis.

16.
Mol Nutr Food Res ; 64(6): e1900873, 2020 03.
Article in English | MEDLINE | ID: mdl-31945799

ABSTRACT

SCOPE: Marine-derived n-3 PUFAs may ameliorate inflammation associated with inflammatory bowel diseases. Plant-derived n-3 PUFAs are thought to be inferior owing to shorter chain lengths. The aim of this study is to compare the impact of plant- and fish-derived PUFAs on murine colitis. METHODS AND RESULTS: C57BL/6 mice are fed high fat (36% kcal) diets with either 2.5% w/w sunflower oil (SO), flaxseed oil (FSO), ahiflower oil (AO), or fish oil (FO). After 4 weeks, mice are orogastrically challenged with Citrobacter rodentium (108 CFU) or sham gavaged. Fecal shedding is assayed at 2, 7, 10, and 14 days post infection (PI), and fecal microbiota at 14 days PI. Colonic inflammation and lipid mediators are measured. Supplementation regulates intestinal inflammation with crypt lengths being 66, 73, and 62 ±17 µm shorter (compared to SO) for FSO, AO, and FO respectively, p < 0.01. FSO blunts pathogen shedding at the peak of infection and FSO and AO both enhance fecal microbial diversity. FO attenuates levels of lipoxin and leukotriene B4 while plant oils increase pro-resolving mediator concentrations including D, E, and T-series resolvins. CONCLUSION: Plant and fish n-3 PUFAs attenuate colitis-induced inflammation while exhibiting characteristic pro-resolving lipid mediator metabolomes. Plant oils additionally promote microbial diversity.


Subject(s)
Citrobacter rodentium/pathogenicity , Colitis/diet therapy , Fatty Acids, Omega-3/pharmacology , Fish Oils/pharmacology , Plant Oils/pharmacology , Animals , Bacterial Shedding/drug effects , Colitis/microbiology , Colitis/pathology , Colon/drug effects , Colon/metabolism , Dietary Supplements , Enterobacteriaceae Infections/diet therapy , Inflammation Mediators/metabolism , Linseed Oil/chemistry , Linseed Oil/pharmacology , Liver/drug effects , Liver/metabolism , Male , Mice, Inbred C57BL , Sunflower Oil/pharmacology
17.
Subst Use Misuse ; 55(2): 209-217, 2020.
Article in English | MEDLINE | ID: mdl-31847657

ABSTRACT

Background: The relationship between psychopathic personality and problematic alcohol consumption could be important for understanding risk and potential interventions. This existing work on psychopathy and alcohol abuse is typically conducted in criminal and hospitalized populations and little attention has been paid to investigating the general populations' psychopathic personality and problematic consumption of alcohol. The psychopathy-focused Triarchic Psychopathy Measure (TriPM) and the more general Reinforcement Sensitivity Theory of personality (RST) focus on individual differences related to low self-control and sensation seeking, and could relate to problematic alcohol consumption in non-forensic samples. The current study brings together RST and psychopathic personality traits to predict alcohol use disorders. We hypothesize that impulsivity and anxiety predict problematic alcohol consumption and related risk appraisal. Methods: We analyzed data from a sample of 349 general population participants who had completed measures of the TriPM, RST, alcohol use disorders (AUDIT), and their perceived negative outcomes of high risk behavior with the Cognitive Appraisal of Risky Events (CARE) measure. Results: We find some evidence that TriPM's disinhibition and RST's anxious personality traits relate to AUDIT scores. We find limited evidence that personality traits predict the negative appraisal of risky events, but alcohol use was related to increased perceptions of the negative outcomes of alcohol consumption. Conclusions: Overall this study shows that individual differences do relate to problematic alcohol consumption but not the appraisal of risks related to alcohol consumption. This has implications for the structuring of intervention for those at-risk of problematic consumption of alcohol.


Subject(s)
Alcohol Drinking/psychology , Alcoholism/psychology , Inhibition, Psychological , Personality , Psychological Theory , Adolescent , Adult , Aged , Alcoholism/complications , Female , Humans , Male , Middle Aged , Personality Inventory , Young Adult
18.
Cell Death Dis ; 10(10): 743, 2019 10 03.
Article in English | MEDLINE | ID: mdl-31582728

ABSTRACT

Necrotizing enterocolitis (NEC) is a devastating neonatal disease characterized by acute intestinal injury. Intestinal stem cell (ISC) renewal is required for gut regeneration in response to acute injury. The Wnt/ß-catenin pathway is essential for intestinal renewal and ISC maintenance. We found that ISC expression, Wnt activity and intestinal regeneration were all decreased in both mice with experimental NEC and in infants with acute active NEC. Moreover, intestinal organoids derived from NEC-injured intestine of both mice and humans failed to maintain proliferation and presented more differentiation. Administration of Wnt7b reversed these changes and promoted growth of intestinal organoids. Additionally, administration of exogenous Wnt7b rescued intestinal injury, restored ISC, and reestablished intestinal epithelial homeostasis in mice with NEC. Our findings demonstrate that during NEC, Wnt/ß-catenin signaling is decreased, ISC activity is impaired, and intestinal regeneration is defective. Administration of Wnt resulted in the maintenance of intestinal epithelial homeostasis and avoidance of NEC intestinal injury.


Subject(s)
Enterocolitis, Necrotizing/physiopathology , Intestines/physiopathology , Regeneration/physiology , Wnt Signaling Pathway , Animals , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Enterocolitis, Necrotizing/genetics , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Gene Expression Regulation/drug effects , Humans , Intestines/drug effects , Intestines/pathology , Mice, Inbred C57BL , Models, Biological , Organoids/drug effects , Organoids/metabolism , Proto-Oncogene Proteins/administration & dosage , Proto-Oncogene Proteins/pharmacology , Regeneration/drug effects , Stem Cells/drug effects , Stem Cells/metabolism , Survival Analysis , Wnt Proteins/administration & dosage , Wnt Proteins/pharmacology , Wnt Signaling Pathway/drug effects , Wnt Signaling Pathway/genetics
19.
Mol Nutr Food Res ; 63(3): e1800658, 2019 02.
Article in English | MEDLINE | ID: mdl-30407734

ABSTRACT

SCOPE: Necrotizing enterocolitis (NEC) is a leading cause of morbidity and death in preterm infants, occurring more often in formula-fed than breastfed infants. Studies in both rats and humans show that human milk oligosaccharides (HMOs) lower the incidence of NEC, but the mechanism underlying such protection is currently unclear. METHODS AND RESULTS: By extracting HMOs from pooled human breastmilk, the impact of HMOs on the intestinal mucin levels in a murine model of NEC are investigated. To confirm the results, the findings are validated by exposing human intestinal epithelial cells and intestinal organoids to HMOs and evaluated for mucin expression. HMO-gavage to pups increases Muc2 levels and decreases intestinal permeability to macromolecular dextran. HMO-treated cells have increased Muc2 expression, decreased bacterial attachment and dextran permeability during challenge by enteric pathogens. To identify the mediators involved in HMO induction of mucins, it is demonstrated that HMOs directly induce the expression of chaperone proteins including protein disulfide isomerase (PDI). Suppression of PDI activity removes the protective effects of HMOs on barrier function in vitro as well as NEC protection in vivo. CONCLUSIONS: Taken together, the results provide insights to the possible mechanisms by which HMOs protect the neonatal intestine through upregulation of mucins.


Subject(s)
Enterocolitis, Necrotizing/prevention & control , Milk, Human/chemistry , Mucin-2/genetics , Oligosaccharides/pharmacology , Animals , Animals, Newborn , Caco-2 Cells , Endoplasmic Reticulum Stress/drug effects , Enterocolitis, Necrotizing/metabolism , Goblet Cells/drug effects , Humans , Intestinal Mucosa/drug effects , Mice , Mice, Inbred C57BL , Mucin-2/analysis , Protein Disulfide-Isomerases/physiology
20.
J Med Chem ; 61(24): 11127-11143, 2018 12 27.
Article in English | MEDLINE | ID: mdl-30380863

ABSTRACT

Selective immunoproteasome inhibition is a promising approach for treating autoimmune disorders, but optimal proteolytic active site subunit inhibition profiles remain unknown. We reveal here our design of peptide epoxyketone-based selective low molecular mass polypeptide-7 (LMP7) and multicatalytic endopeptidase complex subunit-1 (MECL-1) subunit inhibitors. Utilizing these and our previously disclosed low molecular mass polypeptide-2 (LMP2) inhibitor, we demonstrate a requirement of dual LMP7/LMP2 or LMP7/MECL-1 subunit inhibition profiles for potent cytokine expression inhibition and in vivo efficacy in an inflammatory disease model. These and additional findings toward optimized solubility led the design and selection of KZR-616 disclosed here and presently in clinical trials for treatment of rheumatic disease.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Arthritis, Rheumatoid/drug therapy , Morpholines/pharmacology , Proteasome Inhibitors/pharmacology , Administration, Intravenous , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Arthritis, Experimental/drug therapy , Cell Line, Tumor , Cysteine Endopeptidases/metabolism , Cytokines/metabolism , Drug Design , Female , Humans , Mice, Inbred BALB C , Morpholines/chemistry , Morpholines/pharmacokinetics , Oligopeptides/pharmacology , Proteasome Endopeptidase Complex/immunology , Proteasome Endopeptidase Complex/metabolism , Proteasome Inhibitors/chemistry , Proteasome Inhibitors/pharmacokinetics , Structure-Activity Relationship
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