Advancing from immunonutrition to a pharmaconutrition: a gigantic challenge

How Anesthetic, Analgesic and Other Non-Surgical Techniques During Cancer Surgery Might Affect Postoperative Oncologic Outcomes: A Summary of Current State of Evidence

The question of whether anesthetic, analgesic or other perioperative intervention during cancer resection surgery might influence long-term oncologic outcomes has generated much attention over the past 13 years. A wealth of experimental and observational clinical data have been published, but the results of prospective, randomized clinical trials are awaited. The European Union supports a pan-European network of researchers, clinicians and industry partners engaged in this question (COST Action 15204: Euro-Periscope). In this narrative review, members of the Euro-Periscope network briefly summarize the current state of evidence pertaining to the potential effects of the most commonly deployed anesthetic and analgesic techniques and other non-surgical interventions during cancer resection surgery on tumor recurrence or metastasis.

The role of immunonutritional support in cancer treatment: Current evidence

The significant role of the immune system in cancer treatment has given rise to an emerging field of study within oncology, and one that is attracting increasing attention from researchers. Immunotherapy has demonstrated that the immune system is crucial in the fight against cancer. This challenge has led researchers to analyze whether the immune influencing capacity of immunonutrition may aid in improving immune status, modulate the acquired immune response, decrease the treatment toxicity and improve patient outcomes. Immunonutrition, new developed formulas has been demonstrated to improve outcome in surgical patients. This improvement is related to the modulation of the inflammatory response in the peri-operative period. The aim of this review is to analyze current evidence on the benefit of immunonutrition in patients undergoing pro-inflammatory processes in cancer, such as receiving chemotherapy or radiation treatment. With this aim, authors have analyzed the problem studying different aspects: the role of the immune system in cancer treatment, current evidence regarding immunonutrition in perioperative period, current evidence regarding immunonutrition in cancer patients and the relation between immunity and radiotherapy. The conclusions of this review confirm that immunonutrition formulas could modulate inflammatory and immune response in cancer patients. This effect decreases acute toxicity, although the pathways and the measure of this immune response are unclear. Immunonutrition is an emerging field in oncology, and further research is needed.

Prevalence of glutamine deficiency in ICU patients: a cross-sectional analytical study

BACKGROUND

Not only is glutamine deficiency an independent predictor of mortality in intensive care unit (ICU) patients, but glutamine supplementation is also recommended for its proven outcome benefits. However, recent data suggest that early glutamine supplementation in certain patient groups increase mortality. The aim of this study was to investigate plasma glutamine levels of adult ICU patients in the South African setting and to determine relationships between glutamine levels, gender, diagnostic categories and selected inflammatory markers. The data from this study will be used as baseline measurement to support a large scale study that will be undertaken in the South African ICU population.

METHODS

This cross-sectional, analytical study included 60 mixed adult ICU patients within 24 h post ICU admission. Plasma glutamine levels were determined on admission. The relationship between glutamine levels, Interleukin-6 (IL-6) and C-reactive protein (CRP); as well as gender- and diagnosis-related differences in glutamine levels were also investigated. A non-parametric ROC curve was computed to determine the CRP concentration cut-off point above which glutamine becomes deficient.

RESULTS

The median plasma glutamine level (497 μmol/L) was in the normal range; however, 38.3 % (n = 23) of patients had deficient (<420 μmol/L) and 6.7 % (n = 4) had supra-normal glutamine levels (>930 μmol/L). No significant difference could be detected between glutamine levels and gender or diagnosis categories as a group. When only the medical and surgical categories were compared, the median plasma glutamine level of the medical patients were significantly lower than that of the surgical patients (p = 0.042). Glutamine showed inverse associations with CRP levels (r = -0.44, p < 0.05) and IL-6 concentrations (r = -0.23, p = 0.08). A CRP cut-off value of 95.5 mg/L was determined above which glutamine levels became deficient.

CONCLUSIONS

About a third of patients (38 %) were glutamine deficient on admission to ICU, whereas some presented with supra-normal levels. While glutamine levels correlated inversely with inflammatory markers, and a CRP value of above 95.5 mg/L indicated potential glutamine deficiency, the clinical application of this finding needs further investigation.

Innate immunity gene expression changes in critically ill patients with sepsis and disease-related malnutrition

The aim of this study was an attempt to determine whether the expression of genes involved in innate antibacterial response (TL R2, NOD 1, TRAF6, HMGB 1 and Hsp70) in peripheral blood leukocytes in critically ill patients, may undergo significant changes depending on the severity of the infection and the degree of malnutrition. The study was performed in a group of 128 patients with infections treated in the intensive care and surgical ward. In 103/80.5% of patients, infections had a severe course (sepsis, severe sepsis, septic shock, mechanical ventilation of the lungs). Clinical monitoring included diagnosis of severe infection (according to the criteria of the ACC P/SCC M), assessment of severity of the patient condition and risk of death (APACHE II and SAPS II), nutritional assessment (NRS 2002 and SGA scales) and the observation of the early results of treatment. Gene expression at the mRNA level was analyzed by real-time PCR. The results of the present study indicate that in critically ill patients treated in the IC U there are significant disturbances in the expression of genes associated with innate antimicrobial immunity, which may have a significant impact on the clinical outcome. The expression of these genes varies depending on the severity of the patient condition, severity of infection and nutritional status. Expression disorders of genes belonging to innate antimicrobial immunity should be diagnosed as early as possible, monitored during the treatment and taken into account during early therapeutic treatment (including early nutrition to support the functions of immune cells).

Interaction of dietary fatty acids with tumour necrosis factor family cytokines during colon inflammation and cancer

Intestinal homeostasis is precisely regulated by a number of endogenous regulatory molecules but significantly influenced by dietary compounds. Malfunction of this system may result in chronic inflammation and cancer. Dietary essential n-3 polyunsaturated fatty acids (PUFAs) and short-chain fatty acid butyrate produced from fibre display anti-inflammatory and anticancer activities. Both compounds were shown to modulate the production and activities of TNF family cytokines. Cytokines from the TNF family (TNF- α, TRAIL, and FasL) have potent inflammatory activities and can also regulate apoptosis, which plays an important role in cancer development. The results of our own research showed enhancement of apoptosis in colon cancer cells by a combination of either docosahexaenoic acid (DHA) or butyrate with TNF family cytokines, especially by promotion of the mitochondrial apoptotic pathway and modulation of NF κ B activity. This review is focused mainly on the interaction of dietary PUFAs and butyrate with these cytokines during colon inflammation and cancer development. We summarised recent knowledge about the cellular and molecular mechanisms involved in such effects and outcomes for intestinal cell behaviour and pathologies. Finally, the possible application for the prevention and therapy of colon inflammation and cancer is also outlined.

The clinical role of glutamine supplementation in patients with multiple trauma: a narrative review

Glutamine is considered an essential amino acid during stress and critical illness. Parenteral glutamine supplementation in critically ill patients has been shown to improve survival rate and minimise infectious complications, costs and hospital length-of-stay. However, glutamine supplementation in patients receiving enteral nutrition and the best method of administration are still controversial. The purpose of this article is to provide a narrative review of the current evidence and trials of enteral and parenteral glutamine supplementation in multiple trauma patients. A search in PubMed and EMBASE was conducted and relevant papers that investigated the effect of enteral or parenteral glutamine supplementation in patients with multiple trauma were reviewed. Although recent nutritional guidelines recommend that glutamine supplementation should be considered in these patients, further well-designed trials are required to provide a confirmed conclusion. Due to the inconclusive results of enteral glutamine supplementation trials in patients receiving enteral nutrition, future trials should focus on intravenous glutamine supplementation in patients requiring enteral nutrition and on major clinical outcome measures (e.g. mortality rate, infectious complications).

Effect of parenteral selenium supplementation in critically ill patients: a systematic review and meta-analysis

BACKGROUND

It is currently unclear whether parenteral selenium supplementation should be recommended in the management of critically ill patients. Here we conducted a systematic review and meta-analysis to assess the efficacy of parenteral selenium supplementation on clinical outcomes.

METHODS/PRINCIPAL FINDINGS

Randomized trials investigating parenteral selenium supplementation administered in addition to standard of care to critically ill patients were included. CENTRAL, Medline, EMBASE, the Science Citation Index, and CINAHL were searched with complementary manual searches. The primary outcome was all-cause mortality. Trials published in any language were included. Two authors independently extracted data and assessed trial quality. A third author was consulted to resolve disagreements and for quality assurance. Twelve trials were included and meta-analysis was performed on nine trials that recruited critically ill septic patients. These comprised 965 participants in total. Of these, 148 patients (30.7%) in the treatment groups, and 180 patients (37.3%) in control groups died. Parenteral selenium treatment significantly reduced all-cause mortality in critically ill patients with sepsis (relative risk [RR] 0.83, 95% CI 0.70-0.99, p = 0.04, I(2) = 0%). Subgroup analyses demonstrated that the administration schedule employing longer duration (RR 0.77, 95% CI 0.63-0.94, p = 0.01, I(2) = 0%), loading boluses (RR 0.73, 95% CI 0.58-0.94, p = 0.01, I(2) = 0%) or high-dose selenium treatment (RR 0.77, 95% CI 0.61-0.99, p = 0.04, I(2) = 0%) might be associated with a lower mortality risk. There was no evidence of adverse events.

CONCLUSIONS/SIGNIFICANCE

Parenteral selenium supplementation reduces risk of mortality among critically ill patients with sepsis. Owing to the varied methodological quality of the studies, future high-quality randomized trials that directly focus on the effect of adequate-duration of parenteral selenium supplementation for severe septic patients are needed to confirm our results. Clinicians should consider these findings when treating this high-risk population.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2011; CRD42011001768.

Docosahexaenoic fatty acid (DHA) in the regulation of colon cell growth and cell death: a review

BACKGROUND

Experimental, epidemiological and clinical data substantiate the beneficial role of n-3 polyunsaturated fatty acids (PUFAs) in preventing inflammation and cancer of the colon. This review covers the unsaturated docosahexaenoic fatty acid (DHA), describes some of its important cellular and molecular mechanisms, its interaction with another dietary lipid, butyrate and with endogenous apoptotic regulators of the tumour necrosis factor (TNF) family. We also discuss the clinical impact of this knowledge and the use of these lipids in colon cancer prevention and treatment.

RESULTS

From the literature, DHA has been shown to suppress the growth, induce apoptosis in colon cancer cells in vitro and decrease the incidence and growth of experimental tumours in vivo. Based on these data and our own experimental results, we describe and discuss the possible mechanisms of DHA anticancer effects at various levels of cell organization. We show that DHA can sensitize colon cancer cells to other chemotherapeutic/chemopreventive agents and affect the action of physiological apoptotic regulators of the TNF family.

CONCLUSION

Use of n-3 PUFAs could be a relatively non-toxic form of supportive therapy for improving colon cancer treatment and slowing down or preventing its recurrence. However, it is necessary to use them with caution, based on solid scientific evidence of their mechanisms of action from the molecular to the cellular and organism levels.

Antioxidants and micronutrient supplementation in trauma patients

PURPOSE OF REVIEW

This study reviews important nutrients responsible for oxidant-antioxidant balance in trauma patients requiring admission to the ICU and rationale for repletion of antioxidants using pharmaconutrition.

RECENT FINDINGS

Oxidative stress is an underlying cause of critical illness due to oxidant-antioxidant imbalance. Multiple nutrients important to oxidative balance have been studied, yet much variety exists among the dosing, timing, and route of administration. Conflict also exists regarding the benefits of particular single nutrients and the effects of combination therapy. Anticipated results of the Reducing Deaths due to Oxidative Stress trial hope to provide further insight to the use of antioxidants in critically ill patients.

SUMMARY

The goal of this review, though not exhaustive, serves to highlight recent significant studies regarding antioxidant use in the ICU setting while calling for sufficiently powered randomized, controlled trials to elucidate appropriate guidelines for antioxidant administration in regards to ideal dosing, route of administration, timing of administration, duration of therapy, and the role of single versus combination supplementation.

The future of critical care nutrition therapy

At present, we are in a "revival" period in clinical nutrition in critical care, especially in the area of "pharmaconutrition." Adequate nutrition may hinge not only on how many calories are provided but also on the ability to provide key pharmacologically acting nutrients. Traditionally, nutrition has been viewed as vital for metabolism, growth, and repair. But, it is now known that some nutrients, when given in therapeutic doses, appear to serve as pharmacologic agents to improve clinically relevant outcomes. Thus, larger therapeutic doses of specific nutrients may be required to replace acute deficiencies brought on by specific injury or disease states. Recent data also imply that the number of calories and protein delivered early in the intensive care unit (ICU) stay has a significant effect on outcome in at-risk patients. It is thought that the future of ICU nutrition will involve administering early nutrition preferentially via the enteral route. Supplementation by parenteral route may be used in at-risk patients when adequate enteral calories cannot be provided. Specific pharmaconutrients can also be administered as separate components, much like a drug is given. Large multicenter trials are planned or are underway to test these hypotheses. The use of basic clinical pharmacology, molecular biology, and clinical research principles in the study of nutritional therapy will lead to answers on how to administer the right nutrients, in the right amounts, at the right time to critically ill patients.

Glutamine: precursor or nitrogen donor for citrulline synthesis?

Although glutamine is considered the main precursor for citrulline synthesis, the current literature does not differentiate between the contribution of glutamine carbon skeleton vs. nonspecific nitrogen (i.e., ammonia) and carbon derived from glutamine oxidation. To elucidate the role of glutamine and nonspecific nitrogen in the synthesis of citrulline, l-[2-(15)N]- and l-[5-(15)N]glutamine and (15)N-ammonium acetate were infused intragastrically in mice. The amino group of glutamine labeled the three nitrogen groups of citrulline almost equally. The amido group and ammonium acetate labeled the ureido and amino groups of citrulline, but not the delta-nitrogen. D(5)-glutamine also infused in this arm of the study, which traces the carbon skeleton of glutamine, was utilized poorly, accounting for only 0.2-0.4% of the circulating citrulline. Dietary glutamine nitrogen (both N groups) incorporation was 25-fold higher than the incorporation of its carbon skeleton into citrulline. To investigate the relative contributions of the carbon skeleton and nonspecific carbon of glutamine, arginine, and proline to citrulline synthesis, U-(13)C(n) tracers of these amino acids were infused intragastrically. Dietary arginine was the main precursor for citrulline synthesis, accounting for approximately 40% of the circulating citrulline. Proline contribution was minor (3.4%), and glutamine was negligible (0.4%). However, the glutamine tracer resulted in a higher enrichment in the ureido group, indicating incorporation of nonspecific carbon from glutamine oxidation into carbamylphosphate used for citrulline synthesis. In conclusion, dietary glutamine is a poor carbon skeleton precursor for the synthesis of citrulline, although it contributes both nonspecific nitrogen and carbon to citrulline synthesis.

Combined infusion of glutamine and arginine: does it make sense?

PURPOSE OF REVIEW

Glutamine and arginine are conditionally essential amino acids because depletion occurs in stressed conditions. Intravenous glutamine supplementation reduces morbidity and mortality in critically ill patients fed parenterally. In surgical patients, arginine-enriched diets have beneficial effects, but the use of supplemental arginine in critically ill patients should be avoided in most cases.

RECENT FINDINGS

In addition to its role as a fuel, glutamine regulates gut barrier function, immuno-inflammatory response and antioxidant status. Arginine metabolism leads to nitric oxide and/or polyamines and thus modulates the immuno-inflammatory response and wound healing. Glutamine and arginine metabolism are closely related, and therefore may give additive or antagonist effects on several pathways. The effects of combined arginine and glutamine are still poorly documented. Combined administration of arginine and glutamine resulted in additive or synergistic effects on gut barrier function and inflammatory response but arginine reduced glutamine protection against oxidative stress. Preliminary data indicate that the combination may be beneficial during intestinal inflammation, whereas data in surgical or critically ill patients are still lacking.

SUMMARY

Mostly speculative effects of combined infusion of arginine and glutamine are discussed. Future studies are needed in specific pathophysiological conditions to assess whether this combination is beneficial or detrimental.