Early enteral nutrition improves intestinal immune barrier in a rat model of severe acute pancreatitis

Octanoic acid-rich enteral nutrition attenuated hypercatabolism through the acylated ghrelin-POMC pathway in endotoxemic rats

OBJECTIVES

Metabolic disorders and no response to intravenous nutrition because of sepsis have been urgent problems for clinical nutrition support. Enteral nutrition (EN) has been an important clinical therapeutic measure in septic patients; however, simple EN has not demonstrated good performance. This study aimed to investigate the effects of different concentrations of octanoic acid (OA)-rich EN on hypercatabolism in endotoxemic rats and test whether OA-rich EN could attenuate hypercatabolism through the acylated ghrelin-proopiomelanocortin (POMC) pathway.

METHODS

Rats were randomly divided into six groups: sham, lipopolysaccharide (LPS), LPS + EN and LPS + EN + OA (0.25, 0.5, and 1 g/kg, respectively) groups to investigate the effects of different concentrations of OA-rich EN on hypercatabolism in endotoxemic rats. The rats were then randomly divided into four groups: sham, LPS, LPS + OA, and LPS + OA + Go-CoA-Tat, to test whether OA-rich EN attenuated hypercatabolism through the acylated ghrelin-POMC pathway. Rats received nutrition support via a gastric tube for 3 d (100 kcal/kg daily). Insulin resistance, muscle protein synthesis and atrophy, inflammatory cytokines, ghrelin in circulation and hypothalamus, ghrelin O-acyltransferase (GOAT), and the adenosine 5'-monophosphate-activated protein kinase (AMPK)-autophagy-POMC pathway were measured.

RESULTS

Compared with simple EN, OA-rich EN promoted the acylation of ghrelin in a dose-dependent manner and attenuated POMC-mediated hypercatabolism in endotoxemic rats. Inhibition of GOAT activity decreased the level of acylated ghrelin and aggravated POMC-mediated hypercatabolism conferred by OA-rich EN.

CONCLUSIONS

OA-rich EN could increase the level of acylated ghrelin and attenuate hypercatabolism through the acylated ghrelin-POMC pathway compared with simple EN in endotoxemic rats.

Comparison of the effects of different calorie amounts of enteral nutrition in hypercatabolism associated with ghrelin-POMC in endotoxemic rats

Background

Hypercatabolism often occurs in critically ill patients, and it increases infection rates and mortality in these patients. Enteral nutrition (EN) is commonly used in case of hypercatabolism. However, the effect of amount of calories in EN on hypercatabolism remains unexplored.

Objective

Here, we compared the effect of low-calorie, medium-calorie and high-calorie EN on hypercatabolism in the acute phase of endotoxemia, which is associated with gastrointestinal hormones and hypothalamic neuropeptide proopiomelanocortin (POMC).

Methods

Overall 84 adult male Sprague–Dawley rats were used for research. A set of rats were divided into 5 groups, Control (NS) and lipopolysaccharide (LPS) groups were fed a standard chow diet; LPS + L (LPS + 40 kcal/kg/day EN), LPS + M (LPS + 80 kcal/kg/day EN) and LPS + H (LPS + 120 kcal/kg/day EN) groups received EN through a gastric tube for 3 days. Another set of rats were used for parallel control experiment and divided into 5 groups: NS + F (saline + fasting) and LPS + F (LPS + fasting) groups were given no food, NS + L (saline + 40 kcal/kg/day EN), NS + M (saline + 80 kcal/kg/day EN) and NS + H (saline + 120 kcal/kg/day EN) groups received EN through a gastric tube for 3 days. Hypercatabolism was evaluated by assessing skeletal muscle protein synthesis and atrophy, insulin resistance, and corticosterone levels. Moreover, serum inflammatory factors, gastrointestinal hormones, hypothalamic ghrelin, growth hormone secretagogue receptor-1α, hypothalamic neuropeptide, and intestinal injury indicators were detected.

Results

Low-calorie EN effectively increased serum and hypothalamic ghrelin possibly due to slight intestinal barrier damage, thereby decreasing hypothalamic POMC expression; consequently, it alleviated rat insulin resistance, reduced blood cortisol levels and muscle atrophy, and improved the survival rate of rats in the acute phase of endotoxemia. Interestingly, with an increase in calories in enteral nutrition, the aforementioned effects did not increase.

Conclusions

Low-calorie EN could effectively increase gastrointestinal hormone ghrelin by reducing intestinal damage and suppressing POMC expression to ameliorate hypercatabolism when compared with medium-calorie and high-calorie EN. Therefore Low-calorie EN may be preferred for providing EN in the acute stage of endotoxemia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-022-00663-7.

SIRT3-mediated mitochondrial autophagy in refeeding syndrome-related myocardial injury in sepsis rats

Background

Myocardial injury induced by refeeding syndrome (RFS) is one of the important causes of deterioration in critically ill patients. Sirtuin-3 (SIRT3) has been shown to regulate mitochondrial autophagy in myocardial ischemia/reperfusion injury; however, the role of mitochondrial autophagy on RFS-related myocardial injury in patients in critical condition has not been reported on.

Methods

Thirty Sprague-Dawley (SD) rats were divided into 3 groups (n=10 each group): the control group; the standard calorie refeeding (SCR) group; and the low calorie refeeding (LCR) group. The rats were weighed every third or four days from day 1 to day 14. On day 14, all rats were anesthetized and received an echocardiography test. Blood and bronchoalveolar lavage fluid (BALF) were collected and tested for arterial oxygen pressure (PaO2), phosphorus (P), and calcium (Ca), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and cardiac troponin 1 (cTnI), myeloperoxidase (MPO), tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6. The histopathological change of hearts and lungs were evaluated, and lung injury score was calculated. Mitochondrial autophagy related proteins (including Beclin1, LC3, mitofusin-2, Mfn2, PINK1, Parkin, and SIRT3) were analyzed using a Western blot. To evaluate the effect of SIRT3, 20 rats were divided into 2 groups (n=10 each group): The adeno-associated virus 9 (AAV9-Nc) group; and the AAV9-SIRT3 overexpression (AAV9-SIRT3) group. The protocols for rats were the same as the SCR group since day 22 after injection of AAV9. The protein expressions of PINK1, Parkin, and SIRT3 were compared between the AAV9-Nc group and AAV9-SIRT3 group.

Results

SCR caused significant decline in cardiac contractility and increased inflammatory cell infiltration in myocardial tissue. Meanwhile, Beclin1, LC3, PINK1, Parkin, and SIRT3 levels decreased, while Mfn2 showed no significant change. Furthermore, significant positive correlations were also found between SIRT3 and P, PINK1, and Parkin, and significant negative correlations were found between SIRT3 and CK-MB, LDH, and cTnI. Overexpression of SIRT3 activated the PINK1/Parkin mediated mitochondrial autophagy.

Conclusions

SIRT3 has an essential role in RFS-related myocardial injury during LPS induced chronic sepsis in rats, probably via regulating mitochondrial autophagy.

Luzhou-Feier powder reduces inflammatory response and improves intestinal immune barrier in rats with severe acute pancreatitis

As we know, nutritional support plays a key role in the treatment of severe acute pancreatitis (SAP). Since total parenteral nutrition (TPN) was discovered, the mortality of SAP had been greatly reduced. But researchers recently demonstrated that the prognosis of SAP could be improved by early enteral nutrition (EEN), which has been a priority for nutritional support in patients with SAP. However, implementation of total enteral nutrition is often challenging in the early stage of SAP. If the enteral nutrition is overused, the burden on the gastrointestinal tract will be aggravated. Under such circumstances, the combination of enteral and parenteral nutrition for nutritional support of SAP patients would be a better choice. Therefore, in this study, we compared the efficacy of two enteral nutrition agents: traditional nutritional supplement named Luzhou-Feier powder (LZ-FP) and enteral nutritional suspension (TPF) combined with parenteral nutrition to total parenteral nutrition (TPN) in the treatment of SAP rats. Our analysis revealed that the combination of enteral nutrition and parenteral nutrition was more effective than TPN in SAP. And LZ-FP met the requirements for enteral nutrition of SAP supporting its clinical application in SAP. PRACTICAL APPLICATIONS: Luzhou-Feier powder (LZ-FP) is a traditional Chinese nutritional supplement that was originally developed as a nutritional supplement for infants and is currently used for nutritional support in patients with chronic and consumptive diseases. Our research investigated the effect and its possible mechanisms of LZ-FP as early trophic enteral nutrition in SAP rats and compared it with TPF and TPN which have been used clinically. We found that LZ-FP helped to reduce inflammatory response and improve the intestinal immune barrier of SAP. The curative effect of LZ-FP was comparable to that of TPF. And this effect may be achieved by inducing the secretion of gut hormones. Our research indicates that LZ-FP should be considered as an enteral nutrition preparation for SAP.

Effect of regional arterial infusion combined with early enteral nutrition on severe acute pancreatitis

Objective

To measure the therapeutic effects of regional arterial infusion (RAI) in combination with early enteral nutrition (EEN) in patients with severe acute pancreatitis (SAP).

Methods

A prospective randomized controlled study enrolled patients with SAP. They were randomly divided into a conventional treatment group that served as the control and a combination therapy group that received RAI combined with EEN. The Acute Physiology, Age, Chronic Health Evaluation II (APACHE II) scores, the levels of serum biochemical indices, functional recovery, the incidence of complications and total effectiveness rate were evaluated.

Results

A total of 100 patients were enrolled in the study. The APACHE II scores and the concentrations of blood glucose, serum amylase, white blood cell count, C-reactive protein, tumour necrosis factor-α, interleukin (IL)-6, IL-10 and IL-17 were significantly decreased, while albumin and serum calcium and total effectiveness rate in the combination therapy group were significantly higher than in the conventional treatment group. The combination therapy group had a significantly reduced time to abdominal pain relief, time of first defaecation, hospital stay and incidence of complications compared with the conventional treatment group.

Conclusion

The combination of RAI and EEN improved clinical biochemical indices, reduced the incidence of complications and promoted early recovery in patients with SAP.

Changes of plasma acetylcholine and inflammatory markers in critically ill patients during early enteral nutrition: A prospective observational study

BACKGROUND

Acetylcholine (Ach) is the key anti-inflammatory transmitter in the cholinergic anti-inflammatory pathway. In this study, critically ill patients treated with early enteral nutrition (EEN) were observed to explore whether EEN affected Ach levels and inflammation.

METHODS

One hundred thirteen patients were included in this prospective observational study. All patients were provided the early enteral nutrition protocol 24-48 h after admission to the intensive care unit (ICU). Blood samples were collected, and the plasma levels of Ach, cholecystokinin (CCK), and inflammatory markers (tumour necrosis factor alpha (TNF-α), interleukin 1beta (IL1-β), and IL6) were measured on Days 0, 1, 3, 5, and 7. Nutritional intervention data were recorded within one week, including the number of patients receiving nutrition, the number of days nutrition was provided, the caloric intake and protein intake, feeding intolerance and prokinetic drug administration. Other collected data included the sequential organ failure assessment score (SOFA score), the Acute Physiology and Chronic Health Evaluation (APACHE) II score, the use of mechanical ventilation (the number of patients and the duration), use of vasoactive drugs and the number of renal replacement treatments (RRT) received by each patient during their ICU stay. The primary outcome was 28-day mortality. Additionally, we analysed the correlation between plasma Ach levels and inflammation, as well as the correlation between plasma Ach and CCK levels. Moreover, a multivariate regression analysis was performed to examine the independent effects of different variables on 28-day mortality and Ach levels.

RESULTS

The overall 28-day mortality was 28.3% (32/113). Eighty-two patients tolerated enteral nutrition. Compared with Day 0 15.6 (2.8) nmol/l, the plasma Ach level was significantly increased on Day 3 18.6 (6.7) nmol/l, Day 5 19.3 (6.2) nmol/l and Day 7 19.7 (4.3) nmol/l (p < .001). Compared with Day 0176.2 (50.4) pg/ml, the plasma TNF-α level was significantly decreased on Day 3144.0 (77.4) pg/ml, Day 5127.3 (51.8) pg/ml and Day 7111.4 (42.5) pg/ml (p < .05). Compared with Day 0, the plasma IL1-β level was significantly decreased on Day 7 (p < .05). The plasma IL6 level was significantly decreased on Day 5 and Day 7 (p < .05) compared with Day 0. Compared with Day 0, the plasma CCK level was significantly increased on Day 3, 5 and 7 (p < .001). The correlation analysis revealed negative correlations between Ach levels and inflammation (p < .001), and a positive correlation between CCK and Ach levels (r = 0.775, p < .001). A comparison of patients who did or did not tolerate EEN revealed significant differences in the plasma levels of Ach, TNF-α, IL6 and CCK (p < .05). Significant differences in plasma levels of Ach, TNF-α, IL1-β, IL6 and CCK were observed between 28-day survivors and non-survivors (p < .05). The multivariate logistic regression analysis identified vasopressor support, RRT, the administration of EEN, SOFA score, APACHE II score at ICU admission and plasma Ach levels as independent determinants of 28-day mortality. Additionally, the multivariate linear regression analysis identified EEN, plasma lactate, mechanical ventilation, the SOFA score and plasma CCK levels as independent determinants of plasma Ach levels.

CONCLUSIONS

The administration of EEN to critically ill patients contributed to the increased plasma Ach levels and decreased inflammatory markers. The effect of EEN on Ach levels is partially attributed to the increase in CCK levels. Elevated plasma Ach levels indicate a better prognosis. Clinical trials identifier: NCT03612206.

Exploring metabolic biomarkers and regulation pathways of acute pancreatitis using ultra-performance liquid chromatography combined with a mass spectrometry-based metabolomics strategy

Acute pancreatitis (AP), as a common kind of pancreas-based inflammatory disease, is accompanied by a serious and abnormal metabolism. However, the specific metabolic process of AP is still unclear. Novel and effective drugs against acute pancreatitis are urgently required. To explore the metabolic biomarkers and regulation pathways of acute pancreatitis, ultra-performance liquid chromatography (UPLC) combined with a mass spectrometry (MS)-based metabolomics strategy was used. Sixteen male adult Sprague-Dawley rats were divided into two groups: a sham operation group (SO) and an AP model group. The AP animal model was induced via the retrograde ductal infusion of 3.5% sodium taurocholate, and rats in the SO group were infused with 0.9% saline. After serum sample collection and sacrifice, a metabolomics strategy based on UPLC-MS was used to detect serum metabolites and metabolic pathways by comparing the SO and AP model groups through full-scan analysis. A total of 19 metabolites were detected in the serum for highlighting the differences between the two groups: l-arabitol, citric acid, isocitric acid, l-phenylalanine, l-tyrosine, dihydroxyacetone, l-valine, succinic acid, 3-hydroxybutyric acid, uric acid, acetylglycine, palmitic amide, homocysteine, d-glutamine, l-arginine, arachidonic acid, N-acetylserotonin, (R)-3-hydroxy-hexadecanoic acid, and d-mannose. Six crucial metabolic pathways, phenylalanine, tyrosine and tryptophan biosynthesis, arachidonic acid metabolism, glyoxylate and dicarboxylate metabolism and the citrate cycle, were involved; these have potential to become novel targets for the treatment of AP. The ingenuity pathway analysis (IPA) platform is used to gain insights into the metabolic targets in the system, referring to development disorders, cell-to-cell signaling and interactions, cellular assembly and organization, cell compromise, cell growth and proliferation, carbohydrate metabolism and others. It is suggested that UPLC-MS-based metabolomics is capable of accurately depicting the pathological mechanisms of acute pancreatitis, which can drive new drug development.

Acute pancreatitis (AP), as a common kind of pancreas-based inflammatory disease, is accompanied by a serious and abnormal metabolism.

Efficacy comparisons of enteral nutrition and parenteral nutrition in patients with severe acute pancreatitis: a meta-analysis from randomized controlled trials

We conducted a comprehensive analysis to evaluate the treatment efficacy and safety of enteral nutrition (EN) and parenteral nutrition (PN) in severe acute pancreatitis (SAP) patients, and to provide a basis for their evidence based application in a clinical setting. We conducted a systematic online search of the PubMed, Web of Science, Wanfang, and China National Knowledge Infrastructure databases, from their inception to November 2017. Studies were subjected to further screening if they met the inclusion/exclusion criteria. Eleven studies were subjected to qualitative and quantitative synthesis; these included a total of 562 patients (281 for EN and 281 for PN). No significant heterogeneity across studies was found. The results indicated that EN can significantly decrease the mortality rate (relative risk [RR] = 0.43, 95% confidence interval [CI]: 0.23–0.78, P=0.006), and lowers the risk of infection and complications (RR = 0.53, 95% CI: 0.39–0.71, P=0.000) more so than does PN. The EN group had a similar risk of multiple organ failure (MOF) compared with the PN group (RR = 0.63, 95% CI: 0.39–1.02, P=0.059). The use of EN was also found to significantly reduce mean hospitalization time (mean difference = −2.93, 95% CI: −4.52–1.34, P=0.000). No publication bias was found. Our meta-analysis suggested that EN, but not PN, significantly reduced the risk of mortality, infection, and complications for patients with SAP. EN support also decreased the rate of MOF and surgical intervention. EN is recommended as an initial treatment option for patients with SAP.

The optimal timing of enteral nutrition and its effect on the prognosis of acute pancreatitis: A propensity score matched cohort study

BACKGROUND

Early enteral nutrition (EN) can improve the prognosis of acute pancreatitis (AP), but the optimal initiation time is unknown. In this study, the optimal time of early EN was analyzed to disclose the application of early EN in AP.

METHODS

Data of 104 patients with AP were prospectively collected. With secondary infection (infected pancreatic necrosis and extrapancreatic infection) as the primary outcome variable, receiver operating characteristic (ROC) curve was used to calculate the optimal cut-off time of early EN. Propensity score matching was used to adjust for covariates. Secondary outcomes include acute gastrointestinal injury (AGI) grades, serum albumin level, and EN-related complications.

RESULTS

The ROC curve analysis showed that the third day after hospital admission was the best cut-off time of early EN (with the area under the curve of 0.744). After PS matching, the proportion of secondary infection in the early EN group was significantly lower than the late EN group (8.6% vs. 36.5%, P < 0.05). Regression analysis showed that early EN was a protective factor against secondary infection (OR 0.161, 95%CI 0.036-0.718, P < 0.05). The AGI grades and serum albumin levels were better improved in the early EN group (AGI F = 4.468, P < 0.05; serum albumin F = 3.794, P < 0.05).The proportion of EN-related abdominal distension in the early EN group was significantly lower (8.8% vs. 38.5%, P < 0.05).

CONCLUSIONS

Early EN initiated within three days could reduce the risk of secondary infection and improve the nutritional status of patients with acute pancreatitis, with a better tolerance.

Sham Feeding with Chewing Gum in Early Stage of Acute Pancreatitis: A Randomized Clinical Trial

Background

The correlation between sham feeding and acute pancreatitis (AP) has only been examined in limited studies. We aimed to investigate the efficacy and safety of sham feeding in the early stage of AP.

Material/Methods

A randomized controlled clinical trial was performed. Equal groups of AP patients were recruited. Patients in the sham feeding group received chewing gum 4 times a day after admission. All patients in the trial received standard treatment consistent with the guidelines for AP. The primary outcomes were mortality, length of stay (LOS), and medical expenses. Secondary outcomes were the incidence of complications and other adverse events, return of gastrointestinal function, the details of enteral nutrition and intra-abdominal pressure.

Results

From May 2014 to December 2015, a total of 204 patients were recruited. The LOS and hospital costs in the sham feeding group were reduced, although mortality was equivalent between groups. The return of gastrointestinal function occurred earlier in the sham feeding group, with no complications related to gum chewing.

Conclusions

Sham feeding with chewing gum is safe and efficacious in the early stage of AP.