Parenteral but not enteral omega-3 fatty acids (Omegaven) modulate intestinal regrowth after massive small bowel resection in rats

Effect of Dietary Supplements with ω-3 Fatty Acids, Ascorbic Acid, and Polyphenolic Antioxidant Flavonoid on Gene Expression, Organ Failure, and Mortality in Endotoxemia-Induced Septic Rats

Sepsis syndrome develops through enhanced secretion of pro-inflammatory cytokines and the generation of reactive oxygen species (ROS). Sepsis syndrome is characterized by vascular hyperpermeability, hypotension, multiple organ dysfunction syndrome (MODS), and increased mortality, among others. Endotoxemia-derived sepsis is an important cause of sepsis syndrome. During endotoxemia, circulating endotoxin interacts with endothelial cells (ECs), inducing detrimental effects on endothelium function. The endotoxin induces the conversion of ECs into fibroblasts, which are characterized by a massive change in the endothelial gene-expression pattern. This downregulates the endothelial markers and upregulates fibrotic proteins, mesenchymal transcription factors, and extracellular matrix proteins, producing endothelial fibrosis. Sepsis progression is modulated by the consumption of specific nutrients, including ω-3 fatty acids, ascorbic acid, and polyphenolic antioxidant flavonoids. However, the underlying mechanism is poorly described. The notion that gene expression is modulated during inflammatory conditions by nutrient consumption has been reported. However, it is not known whether nutrient consumption modulates the fibrotic endothelial gene-expression pattern during sepsis as a mechanism to decrease vascular hyperpermeability, hypotension, MODS, and mortality. Therefore, the aim of this study was to investigate the impact of the consumption of dietary ω-3 fatty acids, ascorbic acid, and polyphenolic antioxidant flavonoid supplements on the modulation of fibrotic endothelial gene-expression patterns during sepsis and to determine the effects on sepsis outcomes. Our results indicate that the consumption of supplements based on ω-3 fatty acids and polyphenolic antioxidant flavonoids was effective for improving endotoxemia outcomes through prophylactic ingestion and therapeutic usage. Thus, our findings indicated that specific nutrient consumption improves sepsis outcomes and should be considered in treatment.

Regulation of body weight: Lessons learned from bariatric surgery

BACKGROUND

Bariatric or weight loss surgery is currently the most effective treatment for obesity and metabolic disease. Unlike dieting and pharmacology, its beneficial effects are sustained over decades in most patients, and mortality is among the lowest for major surgery. Because there are not nearly enough surgeons to implement bariatric surgery on a global scale, intensive research efforts have begun to identify its mechanisms of action on a molecular level in order to replace surgery with targeted behavioral or pharmacological treatments. To date, however, there is no consensus as to the critical mechanisms involved.

SCOPE OF REVIEW

The purpose of this non-systematic review is to evaluate the existing evidence for specific molecular and inter-organ signaling pathways that play major roles in bariatric surgery-induced weight loss and metabolic benefits, with a focus on Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG), in both humans and rodents.

MAJOR CONCLUSIONS

Gut-brain communication and its brain targets of food intake control and energy balance regulation are complex and redundant. Although the relatively young science of bariatric surgery has generated a number of hypotheses, no clear and unique mechanism has yet emerged. It seems increasingly likely that the broad physiological and behavioral effects produced by bariatric surgery do not involve a single mechanism, but rather multiple signaling pathways. Besides a need to improve and better validate surgeries in animals, advanced techniques, including inducible, tissue-specific knockout models, and the use of humanized physiological traits will be necessary. State-of-the-art genetically-guided neural identification techniques should be used to more selectively manipulate function-specific pathways.

Management of Short Bowel Syndrome (SBS) and Intestinal Failure

Short bowel syndrome (SBS) is a chronic disease whose natural history requires a changing array of management strategies over time. Chief amongst these is the chronic use of parenteral nutrition (PN) to ensure adequate nutritional intake. With time and appropriate management, approximately half of all SBS patients will successfully regain a functional, baseline level of intrinsic bowel function that will allow for them to achieve PN independence. However, the other half of SBS patients will progress into chronic intestinal failure which warrants a change in therapy to include more aggressive medical and potentially surgical measures. This review examines the evolving treatment strategies involved in the management of SBS as well as intestinal failure.

Novel Therapeutic Approaches for Mitigating Complications in Short Bowel Syndrome

Short bowel syndrome (SBS) is a particularly serious condition in which the small intestine does not absorb sufficient nutrients for biological needs, resulting in severe illness and potentially death if not treated. Given the important role of the gut in many signaling cascades throughout the body, SBS results in disruption of many pathways and imbalances in various hormones. Due to the inability to meet sufficient nutritional needs, an intravenous form of nutrition, total parental nutrition (TPN), is administered. However, TPN presents difficulties such as severe liver injury and altered signaling secondary to the continued lack of luminal contents. This manuscript aims to summarize relevant studies into the systemic effects of TPN on systems such as the gut-brain, gut-lung, and gut-liver axis, as well as present novel therapeutics currently under use or investigation as mitigation strategies for TPN induced injury.

Comparative study of the safety and efficacy of SMOFlipid vs non SMOFlipid as TPN for liver transplantation

Background

Liver transplantation (LT) is one of the widely recognised and leading treatments for end-stage liver disease. Nutrition impacts its success. Total parenteral nutrition (TPN) is usually prescribed for patients recommended prolonged fasting after LT. The supplement of SMOFlipid (soybean oil, MCT oil, olive oil, and fish oil) is easily metabolised to produce energy, and it possesses anti-inflammatory effects; however, SMOFlipid emulsion use raises concerns regarding coagulopathy after LT. This study investigated the postoperative correlation between SMOFlipid and coagulation in LT.

Materials and methods

The medical records of 54 recipients of living donor LT between January 2012 and June 2015 were retrospectively reviewed. Patients with pretransplant platelet count <40,000/μL and >40,000/μL were assigned to the non-SMOFlipid (n = 23) group and the SMOFlipid (n = 31) group, respectively.

Results

The coagulation and nutrition profile of patients improved significantly after TPN support. No significant difference was observed in the coagulation profile between SMOFlipid and non-SMOFlipid groups. Although the SMOFlipid group exhibited a higher platelet count than the non-SMOFlipid group on day 7 (P < 0.001), no significant differences were observed in the platelet count on 14 and 30 days after TPN support between the 2 groups.

Conclusion

TPN using SMOFlipid after LT is a good strategy for improving nutritional status without increasing the risks of bleeding and coagulation in patients intolerant of early enteral nutrition. Moreover, SMOFlipid use may not cause coagulopathy up to 14 days after LT. Overall, SMOFlipid provides nutritional benefits without increasing the risk of bleeding.

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TPN usually prescribed for nutrition support at early stage after liver transplantation is important.

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SMOFlipid emulsion supplement in TPN improves nutritional status during early post-LT period within 14 days.

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TPN support with SMOFlipid emulsion does not impair coagulation parameters nor increase the risk of thrombocytopenia.

Omegaven Improves Skin Morphometric Indices in Diabetic Rat Model Wound Healing

The global prevalence of diabetes is estimated to be 200 million people, and it is likely to increase to 333 million people by 2025. Different cells, are known to participate in three main phases of wound healing. Omega-3 fatty acids influence cytokines and growth factors which affects the presence of inflammatory cells in wound area as well, but how this event specifically influences the role of fibroblasts, macrophages and angiogenesis in wound healing is not obviously understood. In this experimental study seventy male Wistar rats after induction of diabetes type-one by streptozotocin (STZ) (55 mg/kg) were divided into two groups, Experimental group receiving omegaven intraperitoneally and control group which underwent the injection of mineral oil. Streptozotocin was used for the induction of diabetes type 1. Diabetic male wistar rats were scarified at 1, 3, 5, 7 and 15 days after the excision was made. To estimate orphometric indices, histological sections were provided by stereological methods. It was found that wound area significantly decreased on day 7 in experimental group by omega-3 fatty acids. The number of fibroblasts increased significantly on days 5 and 7 in the experimental group. The number of neovascular significantly decreased on day 7 in the experimental group. This study implied that it seems omegaven is able to improve morphometric indices during wound healing and make healing faster.

The effect of intravenous lipid emulsions and mucosal adaptation following massive bowel resection

AIMS AND OBJECTIVES

Fish oil (FO) lipid emulsion and a new lipid emulsion (SMOF) are important treatments for intestinal failure-associated liver disease. We evaluated the efficacy of FO and SMOF lipid emulsion on intestinal mucosal adaptation using a total parenteral nutrition (TPN)-supported rat model of short bowel syndrome.

MATERIAL & METHODS

Sprague-Dawley rats underwent jugular vein catheterization and 90% small bowel resection and were divided into three groups: TPN with soy bean oil lipid emulsion (SO group), FO lipid emulsion (FO group), or SMOF (SMOF group). On day 13, the rats were euthanized, and the small intestine was harvested. The microscopic morphology and crypt cell proliferation rate (CCPR) were then evaluated.

RESULTS

The villus height of the ileum in the SMOF group was significantly higher than in the SO group. The crypt depth of the intestine in the SMOF group was significantly lower than in the SO group. The CCPRs of the intestine in the FO and SMOF groups were both higher than in the SO group.

CONCLUSIONS

Lipid emulsion affected the bowel morphology, such as the mucosa as well as the intestinal smooth muscle. Further studies are needed to clarify the mechanisms.

Correlation analysis of omega-3 fatty acids and mortality of sepsis and sepsis-induced ARDS in adults: data from previous randomized controlled trials

Objective

This study aimed to investigate the possible effect of omega-3 fatty acids on reducing the mortality of sepsis and sepsis-induced acute respiratory distress syndrome (ARDS) in adults.

Methods

Medline, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI) database, WangFang database, and Chinese BioMedical Literature Database from their inception to March 6, 2017, were searched using systematic review researching methods. Five factors were analyzed to investigate the correlation between omega-3 fatty acids (either parenteral or enteral supplementation) and mortality rate.

Results

Forty randomized controlled trials (RCTs) were initially included, but only 25 of them assessed mortality. Of these RCTs, nine used enteral nutrition (EN) and 16 used parenteral nutrition (PN). The total mortality rate in the omega-3 fatty acid group was lower than that in the control group. However, the odds ratio (OR) value was not significantly different in the EN or PN subgroup. Eighteen RCTs including 1790 patients with similar severity of sepsis and ARDS were also analyzed. The OR value was not significantly different in the EN or PN subgroup. Omega-3 fatty acids did not show positive effect on improving mortality of sepsis-induced ARDS (p = 0.39). But in EN subgroup, omega-3 fatty acids treatment seemed to have some benefits in reducing mortality rate (p = 0.04). In the RCTs including similar baseline patients, partial correlation analysis found that the concentration ratio of n-6 to n-3 fatty acids had positive correlation with reduction of mortality (RM) (γ = 0.60, P = 0.02), whereas the total number of each RCT had negative correlation with RM (γ = − 0.54, P = 0.05).

Conclusions

This review found that omega-3 fatty acid supplementation could reduce the mortality rate of sepsis and sepsis-induced ARDS. However, further investigation based on suitable concentrations and indications is needed to support the findings.

Omega-3 Fish Oil Reduces Mortality Due to Severe Sepsis with Acute Gastrointestinal Injury Grade III

Background:

Sepsis plays an important role in acute gastrointestinal injury (AGI). Our research was designed to determine the effects of omega-3 fish oil (FO) in patients suffering from severe sepsis combined with AGI III, and the ability of FO to modulate immune function.

Methods:

Seventy-eight patients diagnosed with severe sepsis with AGI III and a need for mechanical ventilation were randomized to two groups. In the FO group, 50 g of long chain fatty acid soybean oil (n = 6) and 10 g of FO (n = 3) were administered as total parenteral nutrition (TPN). The control group was treated with 50 g of long chain fatty acid soybean oil without addition of FO to TPN.

Results:

At baseline, there were no significant differences between the two groups. The 60-day mortality was lower in the FO group. Multiple factor logistic regression analysis revealed that intra-abdominal pressure (IAP) and abdominal infection were correlated with the FO intervention. The patients with abdominal infection demonstrated a lower mortality rate, fewer CD3 T lymphocytes, and fewer helper/inducer T lymphocytes in the FO group compared with the control group. After 7 days, the Marshall Score was lower in the FO group than in the control group.

Conclusion:

FO has positive effects in terms of improving the long-term prognosis of patients with severe sepsis with AGI III. Patients with a high IAP and abdominal infection might experience greater benefit from FO. This effect might be due, in part, to immunomodulation.

SUMMARY

Fish oil (FO) has positive effects in terms of improving the long-term prognosis of patients with severe sepsis with acute gastrointestinal injury Grade III

Patients with a high intra-abdominal pressure and abdominal infection might experience greater benefit from FO

This effect might be due, in part, to immunomodulation.

Abbreviations used: AGI: Acute gastrointestinal injury; FO: Fish oil; TPN: Total parenteral nutrition; IAP: Intra-abdominal pressure; ICU: Intensive Care Unit; MODS: Multiple organ dysfunction syndrome; TLR4: Toll-like receptor 4; DNR: Do Not Resuscitate; WGAP: Working Group of Abdominal Problem; EN: Enteral nutrition; BP: Low blood pressure; CRI: Catheter-related infection; PBS: Phosphate-buffered saline; ELFA: Enzyme-linked fluorescent assay; SD: Standard deviation; PUFAs: Polyunsaturated fatty acids; EPA: Eicosapentenoic acid; DHA: Docosahexaenoic acid.

Persistence of hepatic fibrosis in pediatric intestinal failure patients treated with intravenous fish oil lipid emulsion

BACKGROUND

Pediatric intestinal failure (PIF) is a life-altering chronic condition with significant morbidity and mortality. Omegaven® therapy has been used to treat children with advanced intestinal failure associated liver disease. Our objective was to determine the evolution of hepatic fibrosis in PIF patients who received Omegaven® and describe their clinical outcome.

METHODS

A retrospective review in PIF patients who received Omegaven® was performed. Patients were included if they had liver biopsies completed before Omegaven® therapy and after resolution of hyperbilirubinemia. Biopsy results were evaluated to determine the degree of fibrosis, inflammation, and cholestasis. Clinical and biochemical data was collected.

RESULTS

Six patients were identified. Assessment of fibrosis at last follow-up demonstrated improvement in 2 patients and progression or stable fibrosis in 4/6. All patients demonstrated reduction in cholestasis and inflammation. One patient received a liver/intestine transplant and a second is listed, both of them with progressive fibrosis. One patient achieved full enteral nutrition, while the rest remain partially parenteral nutrition dependent.

CONCLUSION

Use of Omegaven® is associated with reduced cholestasis and inflammation, but with persistence or worsening of fibrosis in some patients. A subset of patients with progressive fibrosis may develop portal hypertension and progressive liver disease.

Use of a novel docosahexaenoic acid formulation vs control in a neonatal porcine model of short bowel syndrome leads to greater intestinal absorption and higher systemic levels of DHA

Infants with short bowel syndrome (SBS) are at high risk for malabsorption, malnutrition, and failure to thrive. The objective of this study was to evaluate in a porcine model of SBS, the systemic absorption of a novel enteral Docosahexaenoic acid (DHA) formulation that forms micelles independent of bile salts (DHA-ALT®). We hypothesized that enteral delivery of DHA-ALT® would result in higher blood levels of DHA compared to a control DHA preparation due to improved intestinal absorption. SBS was induced in term piglets through a 75% mid-jejunoileal resection and the piglets randomized to either DHA-ALT® or control DHA formulation (N=5 per group) for 4 postoperative days. The median±IQR difference in final vs starting weight was 696±425 g in the DHA-ALT® group compared to 132±278 g in the controls (P=.08). Within 12 hours, median±IQR DHA and eicosapentaenoic acid plasma levels (mol%) were significantly higher in the DHA-ALT® vs control group (4.1±0.3 vs 2.5±0.5, P=.009; 0.7±0.3 vs 0.2±0.005, P=.009, respectively). There were lower fecal losses of DHA and greater ileal tissue incorporation with DHA-ALT® vs the control. Morphometric analyses demonstrated an increase in proximal jejunum and distal ileum villus height in the DHA-ALT® group compared to controls (P=.01). In a neonatal porcine model of SBS, enteral administration of a novel DHA preparation that forms micelles independent of bile salts resulted in increased fatty acid absorption, increased ileal tissue incorporation, and increased systemic levels of DHA.

Nutritional strategies to enhance adaptation in intestinal failure

PURPOSE OF REVIEW

This article summarizes the current and potential future nutritional approaches to stimulate adaptation in intestinal failure. Adaptation in this context usually refers to intestinal adaptation but also involves changes in whole body physiology as well as in eating/drinking behavior.

RECENT FINDINGS

Adaptation largely depends on residual functional anatomy. Luminal exposure to complex nutrients is the most important trigger for intestinal adaptation. Enteral fat as well as enteral or parenteral short chain fatty acids have a specific stimulatory effect. Zinc and vitamin A status need to be optimized for adaptation to proceed and be maintained. In the context of maintaining sodium and water homeostasis, flushing the remnant intestine because of uncontrolled thirst/drinking must be avoided. Complications of nutritional care such as malnutrition, intestinal failure-associated liver disease, and recurrent line sepsis also need optimal management.

SUMMARY

Stimulation by luminal nutrients as well as prophylaxis against and treatment of (nutritional) complications are the cornerstones of adaptation to the short bowel situation. Based on ample data from animal studies but only limited evidence in humans specific nutritional stimulators need to be studied more rigorously. As long as such data are missing they can be tried on an individual basis.

Animal models of gastrointestinal and liver diseases. Animal models of infant short bowel syndrome: translational relevance and challenges

Intestinal failure (IF), due to short bowel syndrome (SBS), results from surgical resection of a major portion of the intestine, leading to reduced nutrient absorption and need for parenteral nutrition (PN). The incidence is highest in infants and relates to preterm birth, necrotizing enterocolitis, atresia, gastroschisis, volvulus, and aganglionosis. Patient outcomes have improved, but there is a need to develop new therapies for SBS and to understand intestinal adaptation after different diseases, resection types, and nutritional and pharmacological interventions. Animal studies are needed to carefully evaluate the cellular mechanisms, safety, and translational relevance of new procedures. Distal intestinal resection, without a functioning colon, results in the most severe complications and adaptation may depend on the age at resection (preterm, term, young, adult). Clinically relevant therapies have recently been suggested from studies in preterm and term PN-dependent SBS piglets, with or without a functional colon. Studies in rats and mice have specifically addressed the fundamental physiological processes underlying adaptation at the cellular level, such as regulation of mucosal proliferation, apoptosis, transport, and digestive enzyme expression, and easily allow exogenous or genetic manipulation of growth factors and their receptors (e.g., glucagon-like peptide 2, growth hormone, insulin-like growth factor 1, epidermal growth factor, keratinocyte growth factor). The greater size of rats, and especially young pigs, is an advantage for testing surgical procedures and nutritional interventions (e.g., PN, milk diets, long-/short-chain lipids, pre- and probiotics). Conversely, newborn pigs (preterm or term) and weanling rats provide better insights into the developmental aspects of treatment for SBS in infants owing to their immature intestines. The review shows that a balance among practical, economical, experimental, and ethical constraints will determine the choice of SBS model for each clinical or basic research question.

Short bowel syndrome in infants: the critical role of luminal nutrients in a management program

Short bowel syndrome develops when the remnant mass of functioning enterocytes following massive resections cannot support growth or maintain fluid–electrolyte balance and requires parenteral nutrition. Resection itself stimulates the intestine’s inherent ability to adapt morphologically and functionally. The capacity to change is very much related to the high turnover rate of enterocytes and is mediated by several signals; these signals are mediated in large part by enteral nutrition. Early initiation of enteral feeding, close clinical monitoring, and ongoing assessment of intestinal adaptation are key to the prevention of irreversible intestinal failure. The length of the functional small bowel remnant is the most important variable affecting outcome. The major objective of intestinal rehabilitation programs is to achieve early oral nutritional autonomy while maintaining normal growth and nutrition status and minimizing total parenteral nutrition related comorbidities such as chronic progressive liver disease. Remarkable progress has been made in terms of survivability and quality of life, especially in the context of coordinated multidisciplinary programs, but much work remains to be done.

Citrulline levels following proximal versus distal small bowel resection

PURPOSE

Citrulline, a nonprotein amino acid synthesized by enterocytes, is a biomarker of bowel length and the capacity to wean from parenteral nutrition. However, the potentially variant effect of jejunal versus ileal excision on plasma citrulline concentration [CIT] has not been studied. This investigation compared serial serum [CIT] and mucosal adaptive potential after proximal versus distal small bowel resection.

METHODS

Enterally fed Sprague-Dawley rats underwent sham operation or 50% small bowel resection, either proximal (PR) or distal (DR). [CIT] was measured at operation and weekly for 8 weeks. At necropsy, histologic features reflecting bowel adaptation were evaluated.

RESULTS

By weeks 6-7, [CIT] in both resection groups significantly decreased from baseline (P<0.05) and was significantly lower than the concentration in sham animals (P<0.05). There was no difference in [CIT] between PR and DR at any point. Villus height and crypt density were higher in the PR than in the DR group (P≤0.02).

CONCLUSION

[CIT] effectively differentiates animals undergoing major bowel resection from those with preserved intestinal length. The region of intestinal resection was not a determinant of [CIT]. The remaining bowel in the PR group demonstrated greater adaptive potential histologically. [CIT] is a robust biomarker for intestinal length, irrespective of location of small intestine lost.

Attenuating effects of omega-3 fatty acids (Omegaven) on irradiation-induced intestinal injury in mice

Gastrointestinal injury is a major cause of death following exposure to high levels of irradiation, and no effective treatments are currently available. In this study, we examined the effect of omega-3 fatty acids (Omegaven) on intestinal injury of BALB/c mice induced by irradiation. Intravenously administered 3 days prior to irradiation for 7 consecutive days, Omegaven was shown to improve survival, intestinal morphology including villous height, crypt height and mucosal thickness and the intestinal proliferation compared with saline control. Omegaven also normalized the levels of circulating tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), attenuated the increase of diamino oxidase (DAO) activity and malondialdehyde (MDA) level and recovered the decrease of superoxide dismutase (SOD) activity. Meanwhile, Omegaven attenuated the myelosuppression caused by irradiation. In conclusion, our results suggest that Omegaven enhanced the survival of irradiated mice and minimized the effects of radiation on gastrointestinal injury.

Intestinal mucosal atrophy and adaptation

Mucosal adaptation is an essential process in gut homeostasis. The intestinal mucosa adapts to a range of pathological conditions including starvation, short-gut syndrome, obesity, and bariatric surgery. Broadly, these adaptive functions can be grouped into proliferation and differentiation. These are influenced by diverse interactions with hormonal, immune, dietary, nervous, and mechanical stimuli. It seems likely that clinical outcomes can be improved by manipulating the physiology of adaptation. This review will summarize current understanding of the basic science surrounding adaptation, delineate the wide range of potential targets for therapeutic intervention, and discuss how these might be incorporated into an overall treatment plan. Deeper insight into the physiologic basis of adaptation will identify further targets for intervention to improve clinical outcomes.

Benefits of structured and free monoacylglycerols to deliver eicosapentaenoic (EPA) in a model of lipid malabsorption

In the present study, we used a preclinical model of induced lipolytic enzyme insufficiency, and hypothesized that the use of monoacylglycerols (MAG) will enhance their bioavailability and delivery to the tissues. Experimental diets containing 20% lipids were fed to rats for 21 days with or without Orlistat. The control diet of fish oil (FO), a source of EPA and DHA, was tested against: structured (A) vanillin acetal of sn-2 MAG (Vanil + O) and (B) diacetyl derivative of sn-2 MAG (Acetyl + O) and (C) free MAG (MAG + O). FA profiles with an emphasis on EPA and DHA levels were determined in plasma, red blood cells (RBC), liver, spleen, brain and retina. We observed significant reduction of lipid absorption when rats co-consumed Orlistat. As expected, the FO groups with and without Orlistat showed the biggest difference. The Vanil + O, Acetyl + O and MAG + O groups, demonstrated higher levels of EPA (5.5 ± 1.9, 4.6 ± 1.6 and 5.6 ± 0.6, respectively) in RBC compared with FO + O diets (3.3 ± 0.2, 2.6 ± 0.2). Levels of EPA incorporation, in plasma, were similar to those obtained for RBC, and similar trends were observed for the collected tissues and even with DHA levels. These observations with two MAG derivatives providing the fatty acid esterified in the sn-2 position, show that these molecules are efficient vehicles of EPA in malabsorption conditions which is in line with our hypothesis. Free MAG, characterized as having exclusively sn-1(3) isomers of EPA, demonstrated better absorption efficiencies and accretion to tissues when compared to structured MAG. The study demonstrated that structured and free MAG can be used efficiently as an enteral vehicle to supply bioactive fatty acids such as EPA and DHA in lipid malabsorption where diminished lipolytic activity is the underlying cause.

Effects of ω-3 fish oil lipid emulsion combined with parenteral nutrition on patients undergoing liver transplantation

BACKGROUND

The effect of parenteral nutrition (PN) support supplemented with ω-3 fatty acids was investigated in a randomized, controlled clinical trial at the Affiliated Drum Tower Hospital, Medical School of Nanjing University.

MATERIALS AND METHODS

Ninety-eight patients with the diagnosis of end-stage liver disease or hepatic cellular carcinoma were admitted for orthotopic liver transplantation at the Affiliated Drum Tower Hospital. The patients were randomly divided into 3 groups: diet group (n = 32), PN group (n = 33), and polyunsaturated fatty acid (PUFA) group (n = 33). Patients in the PN and PUFA groups received isocaloric and isonitrogenous PN for 7 days after surgery. Venous heparin blood samples were obtained for assay on days 2 and 9 after surgery. A pathological test was performed after reperfusion of the donor liver and on day 9.

RESULTS

Alanine aminotransferase levels were improved significantly by PUFA treatment compared with traditional PN support (P < .05). Compared with the results on day 9 in the PN group, a significant difference was seen in the extent of increase of the prognostic nutrition index and prealbumin in the PUFA group. The pathological results also showed that ω-3 fatty acid supplementation reduced hepatic cell injury. PUFA therapy also decreased the incidence of infectious morbidities and shortened the posttransplant hospital stay significantly.

CONCLUSION

Posttransplant PN support can greatly improve metabolism of protein and nutrition states of patients. ω-3 fatty acid-supplemented PN significantly reduces injury of the transplanted liver, decreases the incidence of infectious morbidities, and shortens posttransplant hospital stay.

Effect of alpha-naphthylisothiocyanate-induced liver injury on intestinal adaptation in a rat model of short bowel syndrome

BACKGROUND/PURPOSE

Progressive hyperbilirubinemia and end-stage liver failure are among the most serious complications of short bowel syndrome (SBS), representing the principle cause of death in a majority of fatal cases. In the current study, we examined the effects of alpha-naphthylisothiocyanate (ANIT)-induced liver injury on intestinal adaptation in a rat model of SBS.

METHODS

Male rats were divided into four groups: Sham rats underwent bowel transection (n = 8), Sham liver-injury rats underwent bowel transection and IP injection of ANIT (100 mg/kg, n = 8), SBS rats underwent a 75% bowel resection, and SBS-ANIT rats underwent bowel resection and liver injury similar to group sham-ANIT (n = 8). Fourteen days after intervention, liver biopsies and intestinal samples were obtained and evaluated for liver damage and measures of intestinal adaptation. Real time PCR and Western blotting were used to determine the level of bax and bcl-2 mRNA and protein, and p-ERK protein levels. Statistical analysis was performed using the one-way ANOVA test, with p < 0.05 considered statistically significant.

RESULTS

All ANIT-treated animals exhibited histological evidence of liver damage that was associated with the expansion of atypical ductal proliferation near the periportal areas, intense neutrophil infiltration in the liver, increased mitotic activity, Kupfer cells hyperplasia and fatty liver degeneration. ANIT-induced liver damage in bowel resected animals was associated with a significant decrease in all parameters of intestinal adaptation including bowel and mucosal weight in jejunum (twofold decrease) and ileum (twofold decrease), mucosal DNA in jejunum (fourfold decrease), mucosal protein in jejunum (threefold decrease) and ileum (threefold decrease), villus height in jejunum (38%) and ileum (34%), and crypt depth in jejunum (24%) and ileum (30%) compared to SBS animals. Both Sham-ANIT and SBS-ANIT rats demonstrated decreased enterocyte proliferation rates that were accompanied by decreased p-ERK protein levels. Lower apoptotic rates in jejunum (40%) and ileum (52%) in SBS-ANIT rats (vs. SBS) coincided with decreased bax mRNA and protein levels.

CONCLUSIONS

In a rat model of SBS, ANIT-induced liver injury was associated with decreased enterocyte proliferation and inhibited intestinal adaptation.

Parenteral omega-3 fatty acids (Omegaven) modulate intestinal recovery after intestinal ischemia-reperfusion in a rat model

BACKGROUND/PURPOSE

Fatty acids from fish oil (omega-3 polyunsaturated fatty acids, 3PUFAs) are emerging as powerful yet safe disease-modifying nutrients and are protective in severe critical care conditions including ischemia-reperfusion (IR) injury. The purpose of the present study was to examine the effects of 3PUFAs on intestinal structural changes, enterocyte proliferation, and apoptosis after intestinal IR in a rat.

METHODS

Male rats were divided into three experimental groups: sham rats underwent laparotomy, IR rats underwent occlusion of both superior mesenteric artery and portal vein for 30 minutes followed by 48 hours of reperfusion, and 3PUFA-treated IR (IR-3PUFA) rats underwent IR and were treated with Omegaven (Fresenius Kabi, Bad Homburg, Germany) given intraperitoneally at a dose of 1 mL twice a day. Intestinal structural changes (Park injury score, overall bowel and mucosal weight, mucosal DNA and protein, villus height and crypt depth, cell proliferation, and apoptosis) were determined 48 hours after IR. Real-time polymerase chain reaction (PCR) was used to determine the level of bax and bcl-2 messenger RNA.

RESULTS

A significant decrease in bowel and mucosal weight was observed in the ileum of untreated IR rats compared with sham animals. Forty-eight hours after IR, cell apoptosis remained increased in the jejunum and ileum, which coincided with increased bax/bcl-2 ratio. Cell proliferation was increased 48 hours after IR, suggesting tissue repair. Treatment with Omegaven resulted in a significant increase in bowel and mucosal weight in the jejunum and ileum, villus height in the jejunum and ileum, and crypt depth in the jejunum compared with untreated IR animals. IR-3PUFA rats also demonstrated a significantly lower Park injury score in the jejunum and ileum as well as a lower apoptotic index in the ileum compared with untreated IR animals.

CONCLUSIONS

Parenteral Omegaven administration decreases the intestinal mucosal injury and inhibits enterocyte apoptosis after intestinal IR in a rat.