Cold Renal Perfusion During Simulation of Juxtarenal Aortic Aneurysm Repair Reduces Systemic Oxidative Stress and Sigmoid Damage in Rats.

OBJECTIVES: Juxtarenal aortic surgery induces renal ischaemia reperfusion, which contributes to systemic inflammatory tissue injury and remote organ damage. Renal cooling during suprarenal cross clamping has been shown to reduce renal damage. It is hypothesised that renal cooling during suprarenal cross clamping also has systemic effects and could decrease damage to other organs, like the sigmoid colon. METHODS: Open juxtarenal aortic aneurysm repair was simulated in 28 male Wistar rats with suprarenal cross clamping for 45 min, followed by 20 min of infrarenal aortic clamping. Four groups were created: sham, no, warm (37 °C saline), and cold (4 °C saline) renal perfusion during suprarenal cross clamping. Primary outcomes were renal damage and sigmoid damage. To assess renal damage, procedure completion serum creatinine rises were measured. Peri-operative microcirculatory flow ratios were determined in the sigmoid using laser Doppler flux. Semi-quantitative immunofluorescence microscopy was used to measure alterations in systemic inflammation parameters, including reactive oxygen species (ROS) production in circulating leukocytes and leukocyte infiltration in the sigmoid. Sigmoid damage was assessed using digestive enzyme (intestinal fatty acid binding protein - I-FABP) leakage, a marker of intestinal integrity. RESULTS: Suprarenal cross clamping caused deterioration of all systemic parameters. Only cold renal perfusion protected against serum creatinine rise: 0.45 mg/dL without renal perfusion, 0.33 mg/dL, and 0.14 mg/dL (p = .009) with warm and cold perfusion, respectively. Microcirculation in the sigmoid was attenuated with warm (p = .002) and cold renal perfusion (p = .002). A smaller increase of ROS production (p = .034) was seen only after cold perfusion, while leukocyte infiltration in the sigmoid colon decreased after warm (p = .006) and cold perfusion (p = .018). Finally, digestive enzyme leakage increased more without (1.5AU) than with warm (1.3AU; p = .007) and cold renal perfusion (1.2AU; p = .002). CONCLUSIONS: Renal ischaemia/reperfusion injury after suprarenal cross clamping decreased microcirculatory flow, increased systemic ROS production, leukocyte infiltration, and I-FABP leakage in the sigmoid colon. Cold renal perfusion was superior to warm perfusion and reduced renal damage and had beneficial systemic effects, reducing sigmoid damage in this experimental study.

Effects of a Carbohydrate-, Glutamine-, and Antioxidant-Enriched Oral Nutrition Supplement on Major Surgery-Induced Insulin Resistance: A Randomized Pilot Study.

BACKGROUND: Insulin resistance after surgery hampers recovery. Oxidative stress is shown to be involved in the occurrence of postoperative insulin resistance. Preoperative carbohydrate-rich oral nutrition supplements reduce but do not prevent insulin resistance. The aim of the present study was to investigate the effect of a carbohydrate-, glutamine-, and antioxidant-enriched preoperative oral nutrition supplement on postoperative insulin resistance. METHODS: A double-blind randomized controlled pilot study in 18 patients with rectal cancer, who received either the supplement (S) or the placebo (P) 15, 11, and 4 hours preoperatively, was conducted. Insulin sensitivity was studied prior to surgery and on the first postoperative day using a hyperinsulinemic euglycemic 2-step clamp. RESULTS: Hepatic insulin sensitivity (insulin-mediated suppression of glucose production) decreased significantly after surgery in both groups, with no differences between the groups. Peripheral insulin sensitivity (glucose rate of disappearance, Rd) was significantly decreased after surgery in both groups (S: 37.2 [19.1-50.9] vs 20.6 [13.9-27.9]; P: 23.8 [15.7-35.5] vs 15.3 [12.6-19.1] µmol/kg·min) but less pronounced in the supplemented group (P = .04). The percentage decrease in glucose Rd did not differ between the groups. Adipose tissue insulin sensitivity (insulin-mediated suppression of plasma free fatty acids) decreased to the same extent after surgery in both groups. CONCLUSION: Rectal cancer surgery induced profound insulin resistance, affecting glucose and fatty acid metabolism. The preoperative nutrition supplement somewhat attenuated but did not prevent postoperative peripheral insulin resistance.

Local Adjuvant Treatment with Low-Dose CpG-B Offers Durable Protection against Disease Recurrence in Clinical Stage I-II Melanoma: Data from Two Randomized Phase II Trials.

Purpose: Although risk of recurrence after surgical removal of clinical stage I-II melanoma is considerable, there is no adjuvant therapy with proven efficacy. Here, we provide clinical evidence that a local conditioning regimen, aimed at immunologic arming of the tumor-draining lymph nodes, may provide durable protection against disease recurrence (median follow-up, 88.8 months).Experimental Design: In two randomized phase II trials, patients, diagnosed with stage I-II melanoma after excision of the primary tumor, received local injections at the primary tumor excision site within 7 days preceding re-excision and sentinel lymph node (SLN) biopsy of either a saline placebo (n = 22) or low-dose CpG type B (CpG-B) with (n = 9) or without (n = 21) low-dose GM-CSF.Results: CpG-B treatment was shown to be safe, to boost locoregional and systemic immunity, to be associated with lower rates of tumor-involved SLN (10% vs. 36% in controls, P = 0.04), and, at a median follow-up of 88.8 months, to profoundly improve recurrence-free survival (P = 0.008), even for patients with histologically confirmed (i.e., pathologic) stage I-II disease (P = 0.02).Conclusions: Potentially offering durable protection, local low-dose CpG-B administration in early-stage melanoma provides an adjuvant treatment option for a large group of patients currently going untreated despite being at considerable risk for disease recurrence. Once validated in a larger randomized phase III trial, this nontoxic immunopotentiating regimen may prove clinically transformative. Clin Cancer Res; 23(19); 5679-86. ©2017 AACR.

Melanoma Sequentially Suppresses Different DC Subsets in the Sentinel Lymph Node, Affecting Disease Spread and Recurrence.

Melanoma exerts immune-suppressive effects to facilitate tumor progression and metastatic spread. We studied these effects on dendritic cell (DC) and T-cell subsets in 36 melanoma sentinel lymph node (SLN) from 28 stage I-III melanoma patients and determined their clinical significance. Four conventional DC subsets, plasmacytoid DCs, and CD4+, CD8+, and regulatory T cells (Tregs), were analyzed by flow cytometry. We correlated these data to clinical parameters and determined their effect on local and distant melanoma recurrence, with a median follow-up of 75 months. In stage I and II melanoma, increased Breslow thickness (i.e., invasion depth of the primary melanoma) was associated with progressive suppression of skin-derived migratory CD1a+ DC subsets. In contrast, LN-resident DC subsets and T cells were only affected once metastasis to the SLN had occurred. In stage III patients, increased CD4:CD8 ratios in concert with the accumulation of Tregs resulted in decreased CD8:Treg ratios. On follow-up, lower frequencies of migratory DC subsets proved related to local melanoma recurrence, whereas reduced maturation of LN-resident DC subsets was associated with distant recurrence and melanoma-specific survival. In conclusion, melanoma-mediated suppression of migratory DC subsets in the SLN precedes local spread, whereas suppression of LN-resident DC subsets follows regional spread and precedes further melanoma dissemination to distant sites. This study offers a rationale to target migratory as well as LN-resident DC subsets for early immunotherapeutic interventions to prevent melanoma recurrence and spread. Cancer Immunol Res; 5(11); 969-77. ©2017 AACR.

The Mechanisms and Effects of Physical Activity on Breast Cancer.

Breast cancer is the most common cancer in women. An extensive part of this health problem can be prevented by an active lifestyle. Physical activity can reduce the risk of breast cancer, reduce the rate of recurrence, and increase the survival rate of patients with breast cancer. The aim of this review was to summarize our current knowledge regarding the effects of physical activity on breast cancer risk, recurrence, and survival. Furthermore, we investigated 5 possible underlying mechanisms through which physical activity has an influence on breast cancer (ie, a reduction of sex hormones, metabolic hormones, adipokines and oxidative stress, and an improvement of the immune function). In this review, we give a complete overview of this subject.

Enteral Glutamine Administration in Critically Ill Nonseptic Patients Does Not Trigger Arginine Synthesis.

Glutamine supplementation in specific groups of critically ill patients results in favourable clinical outcome. Enhancement of citrulline and arginine synthesis by glutamine could serve as a potential mechanism. However, while receiving optimal enteral nutrition, uptake and enteral metabolism of glutamine in critically ill patients remain unknown. Therefore we investigated the effect of a therapeutically relevant dose of L-glutamine on synthesis of L-citrulline and subsequent L-arginine in this group. Ten versus ten critically ill patients receiving full enteral nutrition, or isocaloric isonitrogenous enteral nutrition including 0.5 g/kg L-alanyl-L-glutamine, were studied using stable isotopes. A cross-over design using intravenous and enteral tracers enabled splanchnic extraction (SE) calculations. Endogenous rate of appearance and SE of glutamine citrulline and arginine was not different (SE controls versus alanyl-glutamine: glutamine 48 and 48%, citrulline 33 versus 45%, and arginine 45 versus 42%). Turnover from glutamine to citrulline and arginine was not higher in glutamine-administered patients. In critically ill nonseptic patients receiving adequate nutrition and a relevant dose of glutamine there was no extra citrulline or arginine synthesis and glutamine SE was not increased. This suggests that for arginine synthesis enhancement there is no need for an additional dose of glutamine when this population is adequately fed. This trial is registered with NTR2285.

Perioperative glutamine supplementation restores disturbed renal arginine synthesis after open aortic surgery: a randomized controlled clinical trial.

Postoperative renal failure is a common complication after open repair of an abdominal aortic aneurysm. The amino acid arginine is formed in the kidneys from its precursor citrulline, and citrulline is formed from glutamine in the intestines. Arginine enhances the function of the immune and cardiovascular systems, which is important for recovery after surgery. We hypothesized that renal arginine production is diminished after ischemia-reperfusion injury caused by clamping of the aorta during open abdominal aortic surgery and that parenteral glutamine supplementation might compensate for this impaired arginine synthesis. This open-label clinical trial randomized patients who underwent clamping of the aorta during open abdominal aortic surgery to receive a perioperative supplement of intravenous alanyl-glutamine (0.5 g·kg(-1)·day(-1); group A, n = 5) or no supplement (group B, n = 5). One day after surgery, stable isotopes and tracer methods were used to analyze the metabolism and conversion of glutamine, citrulline, and arginine. Whole body plasma flux of glutamine, citrulline, and arginine was significantly higher in group A than in group B (glutamine: 391 ± 34 vs. 258 ± 19 µmol·kg(-1)·h(-1), citrulline: 5.7 ± 0.4 vs. 2.8 ± 0.4 µmol·kg(-1)·h(-1), and arginine: 50 ± 4 vs. 26 ± 2 µmol·kg(-1)·h(-1), P < 0.01), as was the synthesis of citrulline from glutamine (4.8 ± 0.7 vs. 1.6 ± 0.3 µmol·kg(-1)·h(-1)), citrulline from arginine (2.3 ± 0.3 vs. 0.96 ± 0.1 µmol·kg(-1)·h(-1)), and arginine from glutamine (7.7 ± 0.4 vs. 2.8 ± 0.2 µmol·kg(-1)·h(-1)), respectively (P < 0.001 for all). In conclusion, the production of citrulline and arginine is severely reduced after clamping during aortic surgery. This study shows that an intravenous supplement of glutamine increases the production of citrulline and arginine and compensates for the inhibitory effect of ischemia-reperfusion injury.

Local delivery of CpG-B and GM-CSF induces concerted activation of effector and regulatory T cells in the human melanoma sentinel lymph node.

Impaired immune effector functions in the melanoma sentinel lymph node (SLN) may allow for early metastatic events. In an effort to determine the optimal way to strengthen immune defenses, 28 clinical stage I-II melanoma patients were randomized in a 3-arm Phase II study to receive, prior to excision and sampling of the SLN, i.d. injections of saline or low-dose CpG-B (CpG), alone or combined with GM-CSF (GM), around the melanoma excision site. We previously described the combined administration of these DC-targeting agents to result in activation and recruitment of potentially cross-presenting BDCA3(+) DCs to the SLN. In this report we describe the effects on effector and regulatory T and NK cell subsets. Local low-dose CpG administration resulted in lower CD4/CD8 ratios, Th1 skewing, increased frequencies of melanoma-specific CD8(+) T cells and possible recruitment of effector NK cells, irrespective of GM co-administration. These immune-potentiating effects were counterbalanced by increased IL-10 production by T cells and significantly higher levels of FoxP3 and CTLA4 in regulatory T cells (Tregs) with correspondingly higher suppressive activity in the SLN. Notably, CpG ± GM-administered patients showed significantly lower numbers of SLN metastases (saline: 4/9, CpG + GM: 1/9, CpG: 0/10, p = 0.04). These findings indicate that i.d. delivery of low-dose CpG ± GM potentially arms the SLN of early-stage melanoma patients against metastatic spread, but that antitumor efficacy may be further boosted by counteracting the collateral activation of Tregs.

Taurine Concentrations Decrease in Critically Ill Patients With Shock Given Enteral Nutrition.

BACKGROUND: Nutrition studies in the intensive care unit (ICU) have shown that adequate enteral nutrition (EN) support has clinical benefits. However, the course of amino acid concentrations in plasma has never been investigated in patients admitted with shock receiving EN. We hypothesized that plasma concentrations, when deficit, increase during EN and that persistent deficiency is associated with poor outcome. METHODS: In 33 septic or cardiogenic shock patients receiving EN, plasma amino acid concentrations were measured during 5 days. Changes in amino acid concentrations, correlations with clinical outcome variables, and regression analyses were studied. RESULTS: On ICU admission, several plasma concentrations were deficient. Plasma concentrations of almost all amino acids increased. In contrast, taurine decreased by >50%, from 47.6 µmol/L on admission to 20.0 µmol/L at day 1, and remained low at day 5. Taurine (admission) correlated with time on mechanical ventilation (R = -0.42, P = .015). Taurine decrease within 24 hours correlated with Acute Physiology and Chronic Health Evaluation II predicted mortality (R = 0.43, P = .017) and Sequential Organ Failure Assessment score (R = 0.36, P = .05). Regression analyses confirmed correlations. CONCLUSIONS: Several amino acids were deficient in plasma on ICU admission but increased during EN. Taurine concentrations declined and were associated with longer periods of mechanical ventilation and ICU support. Fast taurine decline correlated with severity of organ failure. These findings support the role of taurine during ischemia, reperfusion, and inflammation. Taurine may be an essential candidate to enrich nutrition support for critically ill patients, although more research is required.

Surgical Excision with Adjuvant Irradiation for Treatment of Keloid Scars: A Systematic Review.

BACKGROUND: Excision followed by adjuvant irradiation is considered safe and most efficacious for treatment of keloid scars. Recently, different authors published successful treatment protocols and recommended the following: (1) the use of high-dose-rate brachytherapy instead of low-dose-rate brachytherapy or external radiation; (2) a short-time interval between operation and irradiation; (3) single fraction instead of multifraction irradiation; and (4) a minimum of 12- to 24-month follow-up post treatment. METHODS: This study evaluates the above recommendations with a systematic review of the English-language literature, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. Both PubMed and EMBASE were searched. Studies were graded according to the American Society of Plastic Surgeons Rating Levels of Evidence. RESULTS: Thirty-three studies were selected. Six studies were graded as level of evidence type II studies and 27 as type III. High-dose-rate brachytherapy showed lower recurrence rates compared with low-dose-rate brachytherapy and external radiation. A short-time (<7 hours) interval between scar excision and irradiation results in a lower recurrence rate compared with long-time intervals (>24 hours). Single-fraction irradiation showed promising results in terms of recurrence rate and patient convenience. Finally, scar recurrences were seen between 2 and 36 months, with a mean of 15 months. CONCLUSIONS: Based on this systematic review of the literature, the evidence confirms the recommendations stated by authors in the recent years. However, due to the lack of high-quality randomized studies, the quality of this evidence is limited. More randomized studies will generate stronger recommendations.

Nutrition before and during Surgery and the Inflammatory Response of the Heart: A Randomized Controlled Trial.

Major surgery induces a long fasting time and provokes an inflammatory response which increases the risk of infections. Nutrition given before and during surgery can avoid fasting and has been shown to increase the arginine/asymmetric dimetlhylarginine ratio, a marker of nitric oxide availability, in cardiac tissue and increased concentrations of branched chain amino acids in blood plasma. However, the effect of this new nutritional strategy on organ inflammatory response is unknown. Therefore, we studied the effect of nutrition before and during cardiac surgery on myocardial inflammatory response. In this trial, 32 patients were randomised between enteral, parenteral, and no nutrition supplementation (control) from 2 days before, during, up to 2 days after coronary artery bypass grafting. Both solutions included proteins or amino acids, glucose, vitamins, and minerals. Myocardial atrial tissue was sampled before and after revascularization and was analysed immunohistochemically, subdivided into cardiomyocytic, fatty, and fibrotic areas. Inflammatory cells, especially leukocytes, were present in cardiac tissue in all study groups. No significant differences were found in the myocardial inflammatory response between the enteral, parenteral, and control groups. In conclusion, nutrition given before and during surgery neither stimulates nor diminishes the myocardial inflammatory response in patients undergoing coronary artery bypass grafting. The trial was registered in Netherlands Trial Register (NTR): NTR2183.

Intralesional Cryotherapy for the Treatment of Keloid Scars: Evaluating Effectiveness.

BACKGROUND: Intralesional (IL) cryotherapy is a novel treatment technique for keloid scars, in which the scar is frozen from inside. Over the past decade, several studies have been published with varying outcomes. A critical analysis of the current literature is, therefore, warranted to determine whether IL cryotherapy is an alternative to established keloid scar treatments. METHODS: A comprehensive review was performed, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. PubMed and EMBASE were searched from inception. Studies and level of recommendation were graded according to the American Society of Plastic Surgeons criteria. RESULTS: Eight studies meeting the inclusion criteria were selected. The average scar volume decrease ranged from 51% to 63%, but no complete scar eradication was achieved on average. Scar recurrence ranged from 0% to 24%. Hypopigmentation posttreatment was seen mostly in Fitzpatrick 4-6 skin type patients. Finally, complaints of pain and pruritus decreased significantly in most studies. CONCLUSIONS: IL cryotherapy for the treatment of keloid scars shows favorable results in terms of volume reduction and alleviated complaints of pain and pruritus. However, no complete scar eradication is established, and recurrences are seen. Also, persistent hypopigmentation proved a problem in Fitzpatrick 4-6 skin type patients. Summarized, the evidence proved limited and inconsistent resulting in an American Society of Plastic Surgeons grade C recommendation for this type of treatment of keloid scars.

Jejunal Casein Feeding Is Followed by More Rapid Protein Digestion and Amino Acid Absorption When Compared with Gastric Feeding in Healthy Young Men.

BACKGROUND: Dietary protein is required to attenuate the loss of muscle mass and to support recovery during a period of hospitalization. Jejunal feeding is preferred over gastric feeding in patients who are intolerant of gastric feeding. However, the impact of gastric vs. jejunal feeding on postprandial dietary protein digestion and absorption kinetics in vivo in humans remains largely unexplored. OBJECTIVE: We compared the impact of gastric vs. jejunal feeding on subsequent dietary protein digestion and amino acid (AA) absorption in vivo in healthy young men. METHODS: In a randomized crossover study design, 11 healthy young men (aged 21 ± 2 y) were administered 25 g specifically produced intrinsically l-[1-(13)C]phenylalanine-labeled intact casein via a nasogastric and a nasojejunal tube placed ~30 cm distal to the ligament of Treitz. Protein was provided in a 240-mL solution administered over a 65-min period in both feeding regimens. Blood samples were collected during the 7-h postprandial period to assess the increase in plasma AA concentrations and dietary protein-derived plasma l-[1-(13)C]phenylalanine enrichment. RESULTS: Jejunal feeding compared with gastric feeding resulted in higher peak plasma phenylalanine, leucine, total essential AA (EAA), and total AA concentrations (all P < 0.05). This was attributed to a more rapid release of dietary protein-derived AAs into the circulation, as evidenced by a higher peak plasma l-[1-(13)C]phenylalanine enrichment concentration (2.9 ± 0.2 vs. 2.2 ± 0.2 mole percent excess; P < 0.05). The total postprandial plasma AA incremental area under the curve and time to peak did not differ after jejunal vs. gastric feeding. Plasma insulin concentrations increased to a greater extent after jejunal feeding when compared with gastric feeding (275 ± 38 vs. 178 ± 38 pmol/L; P < 0.05). CONCLUSIONS: Jejunal feeding of intact casein is followed by more rapid protein digestion and AA absorption when compared with gastric feeding in healthy young men. The greater postprandial increase in circulating EAA concentrations may allow a more robust increase in muscle protein synthesis rate after jejunal vs. gastric casein feeding. This trial was registered at trialregister.nl as NTR2801.

The Arginine/ADMA Ratio Is Related to the Prevention of Atherosclerotic Plaques in Hypercholesterolemic Rabbits When Giving a Combined Therapy with Atorvastatine and Arginine.

UNLABELLED: Supplementation with arginine in combination with atorvastatin is more efficient in reducing the size of an atherosclerotic plaque than treatment with a statin or arginine alone in homozygous Watanabe heritable hyperlipidemic (WHHL) rabbits. We evaluated the mechanism behind this feature by exploring the role of the arginine/asymmetric dimethylarginine (ADMA) ratio, which is the substrate and inhibitor of nitric oxide synthase (NOS) and thereby nitric oxide (NO), respectively. METHODS: Rabbits were fed either an arginine diet (group A, n = 9), standard rabbit chow plus atorvastatin (group S, n = 8), standard rabbit chow plus an arginine diet with atorvastatin (group SA, n = 8) or standard rabbit chow (group C, n = 9) as control. Blood was sampled and the aorta was harvested for topographic and histological analysis. Plasma levels of arginine, ADMA, cholesterol and nitric oxide were determined and the arginine/ADMA ratio was calculated. RESULTS: The decrease in ADMA levels over time was significantly correlated to fewer aortic lesions in the distal aorta and total aorta. The arginine/ADMA ratio was correlated to cholesterol levels and decrease in cholesterol levels over time in the SA group. A lower arginine/ADMA ratio was significantly correlated to lower NO levels in the S and C group. DISCUSSION: A balance between arginine and ADMA is an important indicator in the prevention of the development of atherosclerotic plaques.

Effect of oral taurine on morbidity and mortality in elderly hip fracture patients: a randomized trial.

Hip fracture patients represent a large part of the elderly surgical population and face severe postoperative morbidity and excessive mortality compared to adult surgical hip fracture patients. Low antioxidant status and taurine deficiency is common in the elderly, and may negatively affect postoperative outcome. We hypothesized that taurine, an antioxidant, could improve clinical outcome in the elderly hip fracture patient. A double blind randomized, placebo controlled, clinical trial was conducted on elderly hip fracture patients. Supplementation started after admission and before surgery up to the sixth postoperative day. Markers of oxidative status were measured during hospitalization, and postoperative outcome was monitored for one year after surgery. Taurine supplementation did not improve in-hospital morbidity, medical comorbidities during the first year, or mortality during the first year. Taurine supplementation lowered postoperative oxidative stress, as shown by lower urinary 8-hydroxy-2-deoxyguanosine levels (Generalized estimating equations (GEE) analysis average difference over time; regression coefficient (Beta): -0.54; 95% CI: -1.08--0.01; p = 0.04), blunted plasma malondialdehyde response (Beta: 1.58; 95% CI: 0.00-3.15; p = 0.05) and a trend towards lower lactate to pyruvate ratio (Beta: -1.10; 95% CI: -2.33-0.12; p = 0.08). We concluded that peri-operative taurine supplementation attenuated postoperative oxidative stress in elderly hip fracture patients, but did not improve postoperative morbidity and mortality.

Adaptations of Arginine's Intestinal-Renal Axis in Cachectic Tumor-Bearing Rats.

Malignancies induce disposal of arginine, an important substrate for the immune system. To sustain immune function, the tumor-bearing host accelerates arginine's intestinal-renal axis by glutamine mobilization from skeletal muscle and this may promote cachexia. Glutamine supplementation stimulates argi-nine production in healthy subjects. Arginine's intestinal-renal axis and the effect of glutamine supplementation in cancer cach-exia have not been investigated. This study evaluated the long-term adaptations of the interorgan pathway for arginine production following the onset of cachexia and the metabolic effect of glutamine supplementation in the cachectic state. Fischer-344 rats were randomly divided into a tumor-bearing group (n = 12), control group (n = 7) and tumor-bearing group receiving a glutamine-enriched diet (n = 9). Amino acid fluxes and net fractional extractions across intestine, kidneys, and liver were studied. Compared to controls, the portal-drained viscera of tumor-bearing rats took up significantly more glutamine and released significantly less citrulline. Renal metabolism was unchanged in the cachectic tumor-bearing rats compared with controls. Glutamine supplementation had no effects on intestinal and renal adaptations. In conclusion, in the cachectic state, an increase in intestinal glutamine uptake is not accompanied by an increase in renal arginine production. The adaptations found in the cachectic, tumor-bearing rat do not depend on glutamine availability.