Non-pharmacologic strategies for the management of intestinal inflammation.

Inflammatory bowel diseases, irritable bowel syndrome, and mucositis are characterized by intestinal inflammation, but vary according to their pathological mechanisms, severity, location, and etiology. Significant intestinal inflammation that occurs in these diseases induces weight loss, nutritional depletion, and gastrointestinal tract dysfunction. Nutritional support is important in alleviating symptoms and improving patients' quality of life. In this review, we summarize some nutritional components used to manage intestinal disorders. These include fatty acids, probiotics, parabiotics, postbiotics, prebiotics, synbiotics, and low FODMAP (LFD) diets. These components and LFD diets have been studied and clinical trials have been designed to develop new strategies to alleviate intestinal inflammation and improve the quality of life. Clinical trials on their use in intestinal inflammation do not allow firm conclusions to be drawn mainly because of the heterogeneity of the dose used and the study design or their inconclusive results. However, in the majority of cases, the use of omega-3, probiotics, parabiotics, postbiotics, prebiotics, synbiotics, and LFD improve the health.

Ginger and 6-gingerol prevent lipopolysaccharide-induced intestinal barrier damage and liver injury in mice.

BACKGROUND: Inflammation-related diseases present a significant public health problem. Ginger is a flavoring spice and medicinal herb with anti-inflammatory activity. This study investigated the preventive effects of ginger extract (GE) and its main bioactive component, 6-gingerol (6G), on lipopolysaccharide (LPS)-induced intestinal barrier dysfunction and liver injury in mice. RESULTS: GE and 6G were orally administered to mice for seven consecutive days before LPS administration. After 24 h, the mice were sacrificed. GE and 6G were found to significantly reverse LPS-induced inflammation in the mouse ileum by modifying the NF-κB pathway. They also alleviated apoptosis in the ileum by downregulating Bax and cytochrome c gene expression and by inhibiting the caspase-3 pathway. Through the aforementioned mechanisms, GE and 6G restored the intestinal barrier by increasing ZO-1 and claudin-1 protein expressions. Gut-derived LPS induced inflammation and apoptosis in the liver; these effects were markedly reversed through GE and 6G treatment. 6G was the most abundant component in GE, as evidenced through liquid chromatography-mass spectrometry, and accounted for >50% of total gingerols and shogaols in GE. CONCLUSION: The current results support the use of GE and 6G as dietary supplements to protect against gut-derived endotoxemia-associated inflammatory response and disorders. © 2021 Society of Chemical Industry.

Probiotics, Nutrition, and the Small Intestine.

PURPOSE OF REVIEW: Probiotics are promising remedial treatments for symptoms of small intestine (SI) diseases and promoters of overall good health. Probiotics play an important role in supporting a healthy SI microbiome (eubiosis), and in preventing establishment of unhealthy microbiota. SI eubiosis promotes optimal nutrient uptake, and optimal nutritional status maintains a healthy SI, reducing the likelihood of SI diseases. It is important to understand the advantages and limitations of probiotic therapies. RECENT FINDINGS: Microbial dysbiosis decreases the capacity of the small bowel to utilize and absorb dietary compounds. In some studies, probiotic supplements containing lactic acid bacteria and Bifidobacterium have been demonstrated effective in supporting beneficial microbes in the SI while improving barrier integrity and reducing nutrient malabsorption and SI disease-related pathology. Strain-specific probiotic therapy may be a natural and effective approach to restoring SI barrier integrity and eubiosis, resulting in improved nutrient absorption and better health, including reducing the incidence of and severity of SI diseases.

The Effect of Gastric Electrical Stimulation on Small Bowel Motility in Patients With Gastroparesis and Concomitant Pancreatic and Small Bowel Dysfunction: From Animal Model to Human Application.

BACKGROUND/AIMS: Patients with gastroparesis often have biliary/pancreatic and small bowel symptoms but the effects of gastric electrical stimulation on small bowel electrical activity of the mid-gut have not been studied. Animal model aim: Establish gastric and upper small bowel/biliary slow wave activity relationships with electrical stimulation. Human study aim: Demonstrate improvement in symptoms associated with proximal small bowel dysmotility in gastric stimulated patients. MATERIALS AND METHODS: Animal model: In vivo evoked responses of duodenal and Sphincter of Oddi measures recorded during gastric electrical stimulation in a nonsurvival swine model (N = 3). High-resolution electrical slow wave mapping of frequency, amplitude, and their ratio, for duodenal and Sphincter of Oddi electrical activity were recorded. Human study: Patients (N = 8) underwent temporary gastric stimulation with small bowel electrodes. Subjective and objective data was collected before and after temporary gastric stimulation. Symptom scores, gastric emptying times, and mucosal electrograms via low-resolution mapping were recorded. RESULTS: Animal gastric stimulation resulted in some changes in electrical activity parameters, especially with the highest energies delivered but the changes were not statistically significant. Human study revealed improvement in symptom and illness severity scores, and changes in small bowel mucosal slow wave activity. CONCLUSIONS: Gastric electrical stimulation in an animal model seems to show nonsignificant effects small bowel slow wave activity and myoelectric signaling, suggesting the existence of intrinsic neural connections. Human data shows more significance, with possible potential for therapeutic use of electrical stimulation in patients with gastroparesis and pancreato-biliary and small bowel symptoms of the mid-gut. This study was limited by the nonsurvival pig model, small sample size, and open label human study.

N-Acetylcysteine protects against intrauterine growth retardation-induced intestinal injury via restoring redox status and mitochondrial function in neonatal piglets.

PURPOSE: Intrauterine growth retardation (IUGR) is detrimental to the intestinal development of neonates, yet satisfactory treatment strategies remain limited. This study was, therefore, conducted using neonatal piglets as a model to investigate the potential of N-acetylcysteine (NAC) to alleviate intestinal damage caused by IUGR. METHODS: Seven normal birth weight (NBW) and fourteen IUGR neonatal male piglets were selected and then fed a basal milk diet (NBW-CON and IUGR-CON groups) or a basal milk diet supplemented with 1.2 g NAC per kg of diet (IUGR-NAC group) from 7 to 21 days of age (n = 7). Parameters associated with the severity of intestinal injury, villus morphology and ultrastructural structure, redox status, and mitochondrial function were analyzed. RESULTS: Compared with the NBW-CON piglets, the IUGR-CON piglets exhibited decreased villus height and greater numbers of apoptotic cells in jejunum, along with the increases in malondialdehyde and protein carbonyl concentrations and a decreased adenosine triphosphate (ATP) content. Treatment with NAC significantly increased jejunal superoxide dismutase activity, reduced glutathione: oxidized glutathione ratio, and the mRNA abundance of nuclear respiratory factor 2, heme oxygenase 1, and superoxide dismutase 2 in the IUGR-NAC piglets compared with the IUGR-CON piglets. In addition, NAC improved the efficiency of mitochondrial oxidative metabolism and ATP generation, ameliorated mitochondrial swelling, and inhibited the overproduction of mitochondrial superoxide anion in the jejunal mucosa. CONCLUSIONS: Dietary supplementation of NAC shows promise for attenuating the early intestinal injury of young piglets with IUGR, probably through its antioxidant action to restore redox status and mitochondrial function.

Insulin-like growth factor-1 as a nutritional monitoring factor in patients with chronic intestinal failure.

BACKGROUND & AIMS: Nutritional monitoring plays an important role in optimizing nutritional support in patients with chronic intestinal failure (CIF) receiving long-term supplementation. Unlike initial nutritional assessment, however, there are no recommended guidelines for establishing a nutritional monitoring index. This study is to evaluate the suitability of insulin-like growth factor-1 (IGF-1) as a nutritional monitoring factor in CIF patients. METHODS: We retrospectively analyzed the correlation between serum nutritional indicators, including IGF-1 levels, and nutritional assessment, nutritional monitoring, and lean body mass in 197 patients with CIF. RESULTS: The mean age of the 197 enrolled patients was 47.22 ± 18.87 years old and; the mean BMI was 16.83 ± 3.31. The mean NRS-2002 score was 3.49 ± 0.83; and moreover, 76.3% of the patients were malnourished. The median length of hospital stay in hospital (LOS) was 18.5 days. IGF-1 was positively correlated with body mass index, hemoglobin, albumin, pre-albumin, retinol-binding protein (RBP), transferrin, serum creatinine (Scr) and cholesterol (p < 0.05 for all). Testing performed over 3 weeks post-admission showed that significantly different weekly changes were observed only in IGF-1, RBP, and Scr during the period of nutritional support (p < 0.05 for each). Multivariate linear regression analysis showed that IGF-1 and body mass index were independent factors influencing fat-free mass, skeletal muscle mass, and body protein mass (p < 0.05 for each). CONCLUSIONS: IGF-1 is suitable for monitoring short-term changes in the nutritional status in CIF patients. This may be attributed to its shorter half-life, greater sensitivity, and better correlation with lean body mass. ClinicalTrials.gov number, NCT03277014.

Intestinal failure in adults: Recommendations from the ESPEN expert groups.

BACKGROUND & AIMS: Intestinal failure (IF) is defined as "the reduction of gut function below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, such that intravenous supplementation is required to maintain health and/or growth". Functionally, it may be classified as type I acute intestinal failure (AIF), type II prolonged AIF and type III chronic intestinal failure (CIF) The ESPEN Workshop on IF was held in Bologna, Italy, on 15-16 October 2017 and the aims of this document were to highlight the current state of the art and future directions for research in IF. METHODS: This paper represents the opinion of experts in the field, based on current evidence. It is not a formal review, but encompasses the current evidence, with emphasis on epidemiology, classification, diagnosis and management. RESULTS: IF is the rarest form of organ failure and can result from a variety of conditions that affect gastrointestinal anatomy and function adversely. Assessment, diagnosis, and short and long-term management involves a multidisciplinary team with diverse expertise in the field that aims to reduce complications, increase life expectancy and improve quality of life in patients. CONCLUSIONS: Both AIF and CIF are relatively rare conditions and most of the published work presents evidence from small, single-centre studies. Much remains to be investigated to improve the diagnosis and management of IF and future studies should rely on multidisciplinary, multicentre and multinational collaborations that gather data from large cohorts of patients. Emphasis should also be placed on partnership with patients, carers and government agencies in order to improve the quality of research that focuses on patient-centred outcomes that will help to improve both outcomes and quality of life in patients with this devastating condition.

Modulation of Intestinal Immune and Barrier Functions by Vitamin A: Implications for Current Understanding of Malnutrition and Enteric Infections in Children.

The micronutrient vitamin A refers to a group of compounds with pleiotropic effects on human health. These molecules can modulate biological functions, including development, vision, and regulation of the intestinal barrier. The consequences of vitamin A deficiency and supplementation in children from developing countries have been explored for several years. These children live in an environment that is highly contaminated by enteropathogens, which can, in turn, influence vitamin A status. Vitamin A has been described to modulate gene expression, differentiation and function of diverse immune cells; however, the underlying mechanisms are not fully elucidated. This review aims to summarize the most updated advances on elucidating the vitamin A effects targeting intestinal immune and barrier functions, which may help in further understanding the burdens of malnutrition and enteric infections in children. Specifically, by covering both clinical and in vivo/in vitro data, we describe the effects of vitamin A related to gut immune tolerance/homeostasis, intestinal barrier integrity, and responses to enteropathogens in the context of the environmental enteric dysfunction. Some of the gaps in the literature that require further research are also highlighted.

Denosumab Improves Bone Mineral Density in Patients With Intestinal Failure Receiving Home Parenteral Nutrition: Results From a Randomized, Controlled Clinical Trial.

AIM: Low bone mineral density (BMD) is commonly reported in patients receiving home parenteral nutrition (HPN). Oral and intravenous calcium, vitamin D, and bisphosphonates have been used to treat BMD but with low efficiency due to their limited absorption and patient compliance. Denosumab is a new drug that helps prevent osteoclast development and activation and led to decreased bone resorption in some studies. The aim of this study was to assess its value in HPN patients. METHODS: Between November 2011 and March 2013, 49 patients receiving HPN (29 women, 20 men, mean age 55.3 years) who met the eligibility criteria were randomly assigned to a denosumab or control group. Regional dual-energy x-ray absorptiometry of the spine and hip was performed before therapy and after 12 months. BMD, T score, and z score were assessed. RESULTS: Fifteen patients received 2 doses of therapy and were fully reassessed after 1 year. At baseline and after 12 months, the absorptiometry revealed T scores of -3.439 standard deviations (SD) vs -2.33 SD at lumbar segment 2 (L2) and -2.957 SD vs -2.067 SD at lumbar segment 3 (L3), z scores of -2.24 SD vs -1.36 SD at L2 and -1.995 vs -1.067 SD at L3, and BMD of 0.801 vs 0.946 at L2 and 0.857 vs 0.979 at L3, respectively. Two serious outcomes were reported, without any correlation to the intervention. Two patients were weaned off HPN and hence discontinued. One patient experienced sciatica, resulting in discontinuation of the intervention. CONCLUSIONS: This study showed that denosumab may be a valuable treatment option for improving BMD in HPN patients.

Predictors of failure of fish-oil therapy for intestinal failure-associated liver disease in children.

BACKGROUND: Parenteral fish-oil (FO) therapy is a safe and effective treatment for intestinal failure-associated liver disease (IFALD). Patients whose cholestasis does not resolve with FO may progress to end-stage liver disease. OBJECTIVE: We sought to identify factors associated with the failure of FO therapy in treating IFALD to guide prognostication and referral guidelines. DESIGN: Prospectively collected data for patients treated with FO at Boston Children's Hospital from 2004 to 2014 were retrospectively reviewed. Resolution of cholestasis was defined as sustained direct bilirubin (DB) <2 mg/dL, and treatment failure as liver transplantation or death while DB was >2 mg/dL as of July 2015. Demographics, laboratory values, and medical history at FO therapy initiation were compared between patients who achieved resolution of cholestasis and those who failed therapy. RESULTS: Among 182 patients treated with FO, 86% achieved resolution of cholestasis and 14% failed therapy. Patients who failed therapy had median (IQR) lower birth weight [1020 g (737, 1776 g) compared with 1608 g (815, 2438 g); P = 0.03] and were older at FO initiation [20.4 wk (9.9, 38.6 wk) compared with 11.7 wk (7.3, 21.4 wk); P = 0.02] than patients whose cholestasis resolved. Patients who failed therapy had more advanced liver disease at therapy initiation than patients whose cholestasis resolved, as evidenced by lower median (IQR) γ-glutamyltransferase [54 U/L (41, 103 U/L) compared with 112 U/L (76, 168 U/L); P < 0.001], higher DB [10.4 mg/dL (7.5, 14.1 mg/dL) compared with 4.4 mg/dL (3.1, 6.6 mg/dL); P < 0.001], and a higher pediatric end-stage liver disease (PELD) score [22 (14, 25) compared with 12 (7, 15); P < 0.001]. A PELD score of ≥15, history of gastrointestinal bleeding, age at FO initiation ≥16 wk, presence of nongastrointestinal comorbidities, and mechanical ventilation at FO initiation were independent predictors of treatment failure. CONCLUSIONS: Most infants with IFALD responded to FO therapy with resolution of cholestasis, and liver transplantation was rarely required. Early FO initiation once biochemical cholestasis is detected in parenteral nutrition-dependent patients is recommended. This trial was registered at clinicaltrials.gov as NCT00910104.

[Clinical effect on infantile food accumulation treated with centripetal tuina therapy at spleen meridian site of different location].

OBJECTIVE: To compare the difference in the clinical efficacy on infantile food accumulation treated with centripetal tuina therapy at spleen meridian site of different location. METHODS: Sixty cases of infantile food accumulation were randomized into a palmar thumb surface group and a radial margin group, 30 cases in each one. In the palmar thumb surface group, the spleen meridian was stimulated with the pushing technique centripetally on the palmar side of the thumb. In the radial margin group, the spleen meridian was stimulated with the pushing, technique centripetally along the radial margin of the thumb. The traditional tuina techniques, such as tuisanguan, yun neibagua were combined in the two groups. The treatment was given once a day, 6 times a week, 12 treatments as one session. After the 1 session of treatment, the main symptom scores before and after treatment were compared in the patients of the two groups, the improvements in the accompanied symptoms were observed, such as appetite, defecation and tongue coating; and the efficacy was evaluated in the two groups. RESULTS: The total effective rates were 93.3% (28/30) and 90.0% (27/30) in the palmar thumb surface group and the radial margin group respectively and the difference was not significant statistically in comparison of the two groups (P > 0.05). After treatment, the main symptom score was improved significantly in the two groups, indicating the significant difference as compared with that before treatment (both P < 0.05). The improvement in foul breathing in the palmar thumb surface group was better than that in the radial margin group (P < 0.05). CONCLUSION: Between the two kinds of pushing techniques at spleen meridian site, pushing on the palmar surface of the thumb and pushing along the radial margin, there is no difference in the total efficacy on infantile food accumulation. Regarding the improvement in foul breathing, the effect in the palmar thumb surface group is better than that in the radial margin group.

Management of acute intestinal failure: A position paper from the European Society for Clinical Nutrition and Metabolism (ESPEN) Special Interest Group.

Intestinal failure (IF) is the consequence of a reduction of gut function below the minimum necessary for the absorption of nutrients from the gastrointestinal tract. Types I and II comprise acute intestinal failure (AIF). Although its prevalence is relatively low, type II AIF is serious and requires specialist multidisciplinary care, often for prolonged periods before its resolution. The key aspects are: sepsis control, fluid and electrolyte resuscitation, optimization of nutritional status, wound care, appropriate surgery and active rehabilitation. The ESPEN Acute Intestinal Failure Special Interest Group (AIF SIG) has devised this position paper to provide a state-of-the-art overview of the management of type II AIF and to point out areas for future research.

Lipid emulsions in the treatment and prevention of parenteral nutrition-associated liver disease in infants and children.

Long-term parenteral nutrition (PN) carries the risk of progressive liver disease in infants with intestinal failure. Although PN-associated liver disease (PNALD) is multifactorial in etiology, components of soybean oil lipid emulsions have been implicated in the disease's pathogenesis. Historically, infants with PNALD who were unable to wean from PN to full enteral feeding developed cirrhosis and end-stage liver disease, which require liver transplantation to survive. Over the past 2 decades, novel strategies for the management of parenteral lipids have improved morbidity and mortality from PNALD in infants with intestinal failure. Current strategies for the treatment of PNALD include restricting the dose of parenteral soybean oil lipid emulsion and/or replacing the soybean oil with a parenteral fish-oil lipid emulsion or emulsions of mixed-lipid sources. The purpose of this report is to review published data that evaluate these strategies in parenteral lipid management for the treatment and prevention of PNALD.

Environmental enteric dysfunction: an overview.

BACKGROUND: Environmental enteric dysfunction (EED) refers to an incompletely defined syndrome of inflammation, reduced absorptive capacity, and reduced barrier function in the small intestine. It is widespread among children and adults in low- and middle-income countries. Understanding of EED and its possible consequences for health is currently limited. OBJECTIVE: A narrative review of the current understanding of EED: epidemiology, pathogenesis, therapies, and relevance to child health. METHODS: Searches for key papers and ongoing trials were conducted using PUBMED 1966-June 2014; ClinicalTrials.gov; the WHO Clinical Trials Registry; the Cochrane Library; hand searches of the references of retrieved literature; discussions with experts; and personal experience from the field. RESULTS: EED is established during infancy and is associated with poor sanitation, certain gut infections, and micronutrient deficiencies. Helicobacter pylori infection, small intestinal bacterial overgrowth (SIBO), abnormal gut microbiota, undernutrition, and toxins may all play a role. EED is usually asymptomatic, but it is important due to its association with stunting. Diagnosis is frequently by the dual sugar absorption test, although other biomarkers are emerging. EED may partly explain the reduced efficacy of oral vaccines in low- and middle-income countries and the increased risk of serious infection seen in children with undernutrition. CONCLUSIONS: Despite its potentially significant impacts, it is currently unclear exactly what causes EED and how it can be treated or prevented. Ongoing trials involve nutritional supplements, water and sanitation interventions, and immunomodulators. Further research is needed to better understand this condition, which is of likely crucial importance for child health and development in low- and middle-income settings.

Conception, Pregnancy, and Lactation Despite Chronic Intestinal Failure Requiring Home Parenteral Nutrition.

BACKGROUND: Short-term parenteral nutrition is commonly accepted to be safe in pregnancy, but knowledge about the management of pregnancy during long-term home parenteral nutrition (HPN) is sparse. METHODS AND RESULTS: A systematic literature review revealed that the published experience is limited to 15 pregnancies with parenteral nutrition from preconception to delivery and beyond. Maternal morbidity was surprisingly low, and fetal outcome was good; however, micronutrient deficiencies may have contributed to fetal anomalies. Herein, we additionally report the case of a 26-year-old Caucasian woman with long-term HPN dependence secondary to short bowel syndrome caused by recurrent thromboembolic mesenteric infarctions who delivered a healthy fetus at 37 weeks of gestation. Individual macronutrient support and adequate micronutrient supplementation ensured normal maternal weight gain and fetal development. Based on the individual maternal risk of recurrent thrombosis, anticoagulant treatment was carefully titrated throughout pregnancy. Furthermore, loss of abdominal domain with a rigid maternal abdominal wall secondary to short bowel syndrome and multiple laparotomies resulted in food intolerance during the third trimester. Still, with multidisciplinary efforts, both mother and the breast-fed infant were in good health at 12 months after delivery. CONCLUSIONS: Taking the reported literature into consideration, we conclude that under the premise of optimal medical care, the risk:benefit ratio for pregnancy of HPN-dependent women seems to be justifiable. To minimize the risks, we recommend preconception counseling and early referral to a tertiary center offering both a high-risk pregnancy unit and a nutrition service. In particular, maternal micronutrient levels should be monitored.

Comparison of liver function with two new/mixed intravenous lipid emulsions in children with intestinal failure.

BACKGROUND/OBJECTIVE: The high incidence of liver disease associated with intravenous soybean lipid has led to development and use of alternative intravenous lipid emulsions (ILEs). The aim of this study was to compare two new/mixed ILEs: a medium-chain triglyceride (MCT) combined with soybean (i.e., Lipofundin) and a combination of both these lipids with additional olive and fish oils (SMOF). SUBJECTS/METHODS: Neonates/premature infants newly starting parenteral nutrition (PN) treatment and children with abnormal liver function tests, alanine transferase (ALT), alkaline phosphatase (ALP), γ-glutamyl transferase (γ-GT) 1.5x upper limit of normal and/or total bilirubin >50 µmol/l for >2 weeks on treatment with PN containing pure soybean ILE (Intralipid 20%; Fresenius Kabi), were started on/changed to either SMOF or Lipofundin. RESULTS of biochemistry and clinical outcome were compared on commencing and discontinuing treatment according to the new ILE used. RESULTS: One hundred and twenty-seven children aged 0-16 (median 0.6) years were included. Fifity-six were given Lipofundin and 71 SMOF. Fifty-three of 127 started PN for the first time and 74 had had previous treatment with Intralipid. During treatment, ALT and ALP levels fell significantly (P<0.008 on SMOF; P<0.05 on Lipofundin), with additional significant reduction in γ-GT with SMOF. Hyperbilirubinaemia incidence decreased from 34% on starting to 24% on discontinuing treatment (P⩽0.05). Infection rate/1000 catheter days, full blood count, serum triglyceride and cholesterol levels were similar with both ILEs. CONCLUSION: Addition of MCT to soybean ILE was associated with improved liver function. There was an even greater improvement when olive and fish oils were also added with higher incidence of resolution of abnormal liver function tests and reduced inflammation.

The gut-liver axis.

PURPOSE OF REVIEW: The liver adaptively responds to extra-intestinal and intestinal inflammation. In recent years, the role of the autonomic nervous system, intestinal failure and gut microbiota has been investigated in the development of hepatic, intestinal and extra-intestinal disease. RECENT FINDINGS: The autonomic nervous system can be stimulated via enteral fat leading to cholecystokinin release, stimulating receptors in the gut and in the brain. This promotes bowel integrity, dampening the inflammatory response to food antigens. Consensus exists that intravenously administered long-chain fatty acids can cause liver damage but randomized-controlled trials are lacking. Disruption of the enterohepatic circulation of bile salts can give rise to cholestasis and nonalcoholic fatty liver disease, which may progress to fibrosis and cirrhosis. Reduced intestinal availability of bile salts reduces stimulation of the farnesoid X receptor. This may induce hepatic bile salt overload and associated hepatotoxicity through reduced action of intestinal fibroblast growth factor 19. Evidence is put forward to suggest that the intestinal microbiota is associated with liver abnormalities. SUMMARY: Enteral lipids reduce inflammation and liver damage during stress or systemic inflammation, whereas parenteral lipid is associated with liver damage. Maintaining the enterohepatic circulation of bile salts limits hepatic cholestasis through an farnesoid X receptor feedback pathway. Changes in gut microbiota composition may induce liver disease.

Fish oil emulsions in the management of intestinal failure-associated liver disease.

The role of parenteral lipid emulsions in the treatment of intestinal failure-associated liver disease (IFALD) is both topical and controversial. There is strong evidence supporting plant-based (soy, olive) lipid emulsions as a key cause for IFALD, especially in neonates. As a result, alternate lipid formulations, most notably fish oil emulsions (FOE) have come into widespread use despite somewhat limited clinical data on their overall benefit and potential long-term consequences. This review examines putative mechanisms of action of FOE in reversing cholestasis associated with IFALD, and critically reviews published clinical studies of the use of FOE in pediatric patients with IFALD. From these works, it appears the mechanism of action of FOE is most likely related to the reduction of serum phytosterols associated with plant-based lipid emulsions rather than a specific positive benefit of the fish oils themselves. Although the use of FOE seems to correlate with a reduction in cholestasis, their actual individual benefit is not established, and data on long-term outcomes and safety are not yet available.

Syndecan 1 plays a novel role in enteral glutamine's gut-protective effects of the postischemic gut.

Syndecan 1 is the predominant heparan sulfate proteoglycan found on the surface of epithelial cells and, like glutamine, is essential in maintaining the intestinal epithelial barrier. We therefore hypothesized that loss of epithelial syndecan 1 would abrogate the gut-protective effects of enteral glutamine. Both an in vitro and in vivo model of gut ischemia-reperfusion (IR) was utilized. In vitro, intestinal epithelial cells underwent hypoxia-reoxygenation to mimic gut IR with 2 mM (physiologic) or 10 mM glutamine supplementation. Permeability, caspase activity, cell growth, and cell surface and shed syndecan 1 were assessed. In vivo, wild-type and syndecan 1 knockout (KO) mice received ± enteral glutamine followed by gut IR. Intestinal injury was assessed by fluorescent dye clearance and histopathology, permeability as mucosal-to-serosal clearance ex vivo in everted sacs, and inflammation by myeloperoxidase (MPO) activity. In an in vitro model of gut IR, glutamine supplementation reduced epithelial cell permeability and apoptosis and enhanced cell growth. Shed syndecan 1 was reduced by glutamine without an increase in syndecan 1 mRNA. In vivo, intestinal permeability, inflammation, and injury were increased after gut IR in wild-type mice and further increased in syndecan 1 KO mice. Glutamine's attenuation of IR-induced intestinal hyperpermeability, inflammation, and injury was abolished in syndecan 1 KO mice. These results suggest that syndecan 1 plays a novel role in the protective effects of enteral glutamine in the postischemic gut.