Intragastric infusion of a liquid diet with low-methoxyl pectin alleviates fecal inconsistency and local proinflammatory cytokine expression in lipopolysaccharide-septic rats.

OBJECTIVE: Diarrhea interrupts enteral nutrition management in hospitalized patients with severe illnesses, such as sepsis. Pectin, a water-soluble dietary fiber, has the potential to maintain intestinal function and may reduce inflammatory reactions. The aim of this study was to demonstrate that the addition of low-methoxyl (LM) pectin to a liquid diet suppresses softening of stool texture and reduces tissue inflammatory responses in enteral nutrition management during sepsis. METHODS: A fat-enriched liquid diet with LM pectin (P-EN) or a liquid diet without dietary fiber (FF-EN) was given continuously to rats through a gastric catheter. Lipopolysaccharide (LPS; 10 mg/kg) was injected intraperitoneally 24 h (study 1) and 7 h (study 2) before sacrifice. RESULTS: LPS injection significantly worsened fecal property scores in rats infused with FF-EN compared with the rats given P-EN in study 1. Whereas many myeloperoxidase-positive cells infiltrated the liver, and the hepatic expressions of chemokine genes were markedly elevated 24 h after LPS administration, these findings were clearly alleviated in the LM pectin-containing liquid diet group. In study 2, protein expressions of proinflammatory cytokines, such as small intestinal tumor necrosis factor-α and hepatic interleukin-1ß, and interleukin-6, were significantly downregulated in the P-EN LPS group compared with the FF-EN LPS group. CONCLUSIONS: A liquid diet containing LM pectin allows enteral nutrition management with a low risk for diarrhea and reduces local inflammation under septic conditions.

Methionine supplementation spares body protein by regulating the expression of mTORC1 downstream factors in rats fed a soy protein diet with sufficient sulfur amino acids: a pilot study.

Dietary supplementation with methionine and threonine spares body protein in rats fed a low protein diet, but the effect is not observed for other essential amino acids. Although the requirement for sulfur amino acids is relatively high in rodents, the precise mechanisms underlying protein retention are not fully understood. The aim of this study was to explore whether the activation of mammalian target of rapamycin complex 1 (mTORC1) downstream factors in skeletal muscle by supplementation with threonine and/or methionine contributes to protein retention under sufficient cystine requirement. Male Sprague-Dawley rats were freely fed a 0% protein diet for 2 weeks. These experimental rats were then fed a restricted diet (14.5 g/day) containing 12% soy protein supplemented with both cystine and, methionine and threonine (MT), methionine (M), threonine (T), or neither (NA) (n = 8) for an additional 12 days. Two additional groups were freely fed a diet containing 0% protein or 20% casein as controls (n = 6). Body weight and gastrocnemius muscle weight were higher, and blood urea nitrogen and urinary nitrogen excretion were lower, in the M and MT groups than in the T and NA groups, respectively. p70 S6 kinase 1 abundance was higher, and eukaryotic translation initiation factor 4E-binding protein 1 abundance and mRNA levels were lower, in the skeletal muscles of the M and MT groups. These results suggest that methionine regulates mTORC1 downstream factors in skeletal muscle, leading to spare body protein in rats fed a low protein diet meeting cystine requirements.

How to perform appropriate flushing after lipid emulsion administration using totally implantable venous access devices in long-term total parenteral nutrition and home parenteral nutrition.

BACKGROUND & AIMS: There has been no clear evidence regarding the appropriate method of flushing catheters and totally implantable venous access devices (TIVADs) after lipid emulsion (LE) administration. Therefore, the aim of the study was to identify appropriate methods of flushing to minimize residual LE when using TIVADs to ensure the safety of long-term total parenteral nutrition (TPN) and home parenteral nutrition (HPN). METHODS: A soybean oil LE containing indocyanine green (ICG) was administered from the injection site of the primary infusion set for flowing TPN, and LE dynamics were evaluated by a fluorescence imaging system. TIVADs were connected to the end of the infusion sets. After LE administration, the tubes and chambers were flushed from the injection site using saline at various speeds (20, 40, 60 mL/min), with and without pulsation. The washout effect of TPN solution after LE administration followed by flushing was examined, as was the washout effect of size differences in the infusion sets. RESULTS: When the LE was flushed with 20 mL of saline immediately after administering the LE using a standard infusion set (inner diameter 2.5 mm), the LE still remained in the tubes and chambers under any flushing condition. Flushing the LE from the injection site with 10 mL of saline and then flowing >240 mL of TPN solution were effective for minimizing residual LE inside the tubes and chambers. When using an infusion set with a small inner diameter (1.0 mm), the LE inside the tubes and chambers was almost discharged with ≥20 mL of saline immediately after administering the LE. In all settings, flushing with/without pulsation did not affect LE washout efficacy. CONCLUSIONS: Flushing immediately with saline ≥10 mL and then flowing >240 mL of primary PN solution after soybean oil LE administration using the standard infusion set or flushing with 20 mL saline immediately after administering the soybean oil LE using the infusion set with a small inner diameter are effective for minimizing the residual LE in the catheter and TIVAD, ensuring the safety of long-term TPN and HPN.

Fecal imaging demonstrates that low-methoxyl pectin supplementation normalizes gastro-intestinal transit in mice given a liquid diet.

This study has the following aims: (1) to confirm a methodology for a fecal indocyanine green (ICG) imaging test for measuring gastro-intestinal transit time (GITT); and (2) to compare GITT in mice given a liquid diet in which viscosity increases under acidic conditions to that in mice given stable liquid diets with comparable viscosity or regular chow. To address Aim 1, mice received ICG orally along with intraperitoneal injection of atropine in Study 1, and mice were given ICG orally with concurrent carmine red for Study 2. Fluorescence imaging of feces collected for 8 h thereafter was used to detect the first feces with fluorescence and thereby determine GITT. To address Aim 2, mice were fed ad libitum for 1 week with either liquid diet or regular chow for Study 3, or with liquid diet containing low-methoxyl (LM) pectin or high-methoxyl (HM) pectin, or regular chow for Study 4. GITT was then determined by fecal ICG imaging. Atropine delayed GITT in a dose-dependent manner. The GITT of ICG completely corresponded to that of carmine red (correlation coefficient, 1.00). The first ICG excretion in the loose/some diarrheal feces of mice given a liquid diet was seen at 170 min. Feces of mice given liquid diet were loose with LM pectin and loose/some diarrhea with HM pectin. GITT of mice given liquid diet with HM pectin was significantly delayed (280 min) compared to that of mice given liquid diet with LM pectin (111 min) or regular chow (130 min). Fecal imaging of ICG enables measurements of GITT. LM pectin supplementation in a liquid diet may normalize GITT in mice to that of a normal meal and may be associated with changes in fecal properties.

Fluorescence imaging in vivo visualizes delayed gastric emptying of liquid enteral nutrition containing pectin.

BACKGROUND: Semi-solidification by gelation or increased viscosity could slow the influx of liquid enteral nutrition (EN) into the small intestine. A liquid EN formula containing pectin that gels under acidic conditions such as those found in the stomach has been developed. A new near-infrared fluorescent imaging reagent was used to non-invasively acquire real time images of gastric emptying in a murine model in vivo. We postulated that the EN formula delays gastric emptying and tested this hypothesis using imaging in vivo. METHODS: Male BALB/c mice were given an oral bolus injection of a liquid EN containing the fluorescence reagent GastroSense750 with or without pectin. The EN in the stomach was visualized in vivo at various intervals using a non-invasive live imaging system and fluorescent signals were monitored from the stomach, which was removed at 60 min after EN ingestion. RESULTS: The fluorescence intensity of signals in stomachs in vivo and in resected stomachs was lower and attenuated over time in mice given EN without, than with pectin. CONCLUSIONS: Adding a gelling agent such as pectin delayed the transit of liquid EN from the stomach. Fluorescence imaging can visualize the delayed gastric emptying of EN containing pectin.