Glutamine supplementation in cancer patients

Influence of Amino Acids and Exercise on Muscle Protein Turnover, Particularly in Cancer Cachexia

Cancer cachexia is a multifaceted syndrome that impacts individuals with advanced cancer. It causes numerous pathological changes in cancer patients, such as inflammation and metabolic dysfunction, which further diminish their quality of life. Unfortunately, cancer cachexia also increases the risk of mortality in affected individuals, making it an important area of focus for cancer research and treatment. Several potential nutritional therapies are being tested in preclinical and clinical models for their efficacy in improving muscle metabolism in cancer patients. Despite promising results, no special nutritional therapies have yet been validated in clinical practice. Multiple studies provide evidence of the benefits of increasing muscle protein synthesis through an increased intake of amino acids or protein. There is also increasing evidence that exercise can reduce muscle atrophy by modulating protein synthesis. Therefore, the combination of protein intake and exercise may be more effective in improving cancer cachexia. This review provides an overview of the preclinical and clinical approaches for the use of amino acids with and without exercise therapy to improve muscle metabolism in cachexia.

The Role of Perioperative Nutritional Status and Supplementation in Orthopaedic Surgery: A Review of Postoperative Outcomes

» Identification of malnourished and at-risk patients should be a standardized part of the preoperative evaluation process for every patient.» Malnourishment is defined as a disorder of energy, protein, and nutrients based on the presence of insufficient energy intake, weight loss, muscle atrophy, loss of subcutaneous fat, localized or generalized fluid accumulation, or diminished functional status.» Malnutrition has been associated with worse outcomes postoperatively across a variety of orthopaedic procedures because malnourished patients do not have a robust metabolic reserve available for recovery after surgery.» Screening assessment and basic laboratory studies may indicate patients' nutritional risk; however, laboratory values are often not specific for malnutrition, necessitating the use of prognostic screening tools.» Nutrition consultation and perioperative supplementation with amino acids and micronutrients are 2 readily available interventions that orthopaedic surgeons can select for malnourished patients.

Glutamine Supplementation as an Anticancer Strategy: A Potential Therapeutic Alternative to the Convention

Glutamine, a multifaceted nonessential/conditionally essential amino acid integral to cellular metabolism and immune function, holds pivotal importance in the landscape of cancer therapy. This review delves into the intricate dynamics surrounding both glutamine antagonism strategies and glutamine supplementation within the context of cancer treatment, emphasizing the critical role of glutamine metabolism in cancer progression and therapy. Glutamine antagonism, aiming to disrupt tumor growth by targeting critical metabolic pathways, is challenged by the adaptive nature of cancer cells and the complex metabolic microenvironment, potentially compromising its therapeutic efficacy. In contrast, glutamine supplementation supports immune function, improves gut integrity, alleviates treatment-related toxicities, and improves patient well-being. Moreover, recent studies highlighted its contributions to epigenetic regulation within cancer cells and its potential to bolster anti-cancer immune functions. However, glutamine implementation necessitates careful consideration of potential interactions with ongoing treatment regimens and the delicate equilibrium between supporting normal cellular function and promoting tumorigenesis. By critically assessing the implications of both glutamine antagonism strategies and glutamine supplementation, this review aims to offer comprehensive insights into potential therapeutic strategies targeting glutamine metabolism for effective cancer management.

Evaluation of an onco-diet on body composition and inflammatory status of dogs with mammary tumor-Pilot study

A high-protein hypercaloric diet enriched with glutamine and omega-3 polyunsaturated fatty acids was called an onco-diet. The goal was to verify the modulation of the inflammatory response and body composition of female dogs with mammary tumor after mastectomy, during onco-diet consumption, using a randomized, double-blinded, clinical trial. Six bitches (average age of 8.6 years) were allocated into Control Group-diet without glutamine, EPA and DHA supplementation; and six bitches (10.0 years) were allocated into Test-diet enriched with glutamine and omega-3. Serum measurements of TNF-α, IL-6, IL-10, IGF-1, C-reactive protein and determination of body composition were performed at pre- and post-surgical times. Statistical tests were used to compare the nutrient intake and dietary effects on inflammatory variables between the diets. No differences in concentrations of different cytokines (p>0.05) and C-reactive protein (CRP) (p = 0.51) were observed between the groups. The test group had a higher concentration of IGF-1 (p<0.05), higher percentage of muscle mass (p<0.01) and lower body fat (p<0.01), but the difference was present from initial and throughout the study. Onco-diet, enriched with glutamine and omega-3, in the amounts evaluated in this study, was not sufficient to modulate the inflammation and body composition of female dogs with mammary tumors submitted to unilateral mastectomy.

Targeting cancer cachexia: Molecular mechanisms and clinical study

Cancer cachexia is a complex systemic catabolism syndrome characterized by muscle wasting. It affects multiple distant organs and their crosstalk with cancer constitute cancer cachexia environment. During the occurrence and progression of cancer cachexia, interactions of aberrant organs with cancer cells or other organs in a cancer cachexia environment initiate a cascade of stress reactions and destroy multiple organs including the liver, heart, pancreas, intestine, brain, bone, and spleen in metabolism, neural, and immune homeostasis. The role of involved organs turned from inhibiting tumor growth into promoting cancer cachexia in cancer progression. In this review, we depicted the complicated relationship of cancer cachexia with the metabolism, neural, and immune homeostasis imbalance in multiple organs in a cancer cachexia environment and summarized the treatment progress in recent years. And we discussed the molecular mechanism and clinical study of cancer cachexia from the perspective of multiple organs metabolic, neurological, and immunological abnormalities. Updated understanding of cancer cachexia might facilitate the exploration of biomarkers and novel therapeutic targets of cancer cachexia.

Molecular Mechanisms and Current Treatment Options for Cancer Cachexia

Simple Summary

The primary characteristics of cancer cachexia are weakness, weight loss, atrophy, fat reduction, and systemic inflammation. Cachexia is strongly associated with cancers involving the lungs, pancreas, esophagus, stomach, and liver, which account for half of all cancer deaths. TGF-β, MSTN, activin, IGF-1/PI3K/AKT, and JAK-STAT signaling pathways are known to underlie muscle atrophy and cachexia. Anamorelin (appetite stimulation), megestrol acetate, eicosapentaenoic acid, phytocannabinoids, targeting MSTN/activin, and molecules targeting proinflammatory cytokines, such as TNF-α and IL-6, are being tested as treatment options for cancer cachexia.

Abstract

Cancer cachexia is a condition marked by functional, metabolic, and immunological dysfunctions associated with skeletal muscle (SM) atrophy, adipose tissue loss, fat reduction, systemic inflammation, and anorexia. Generally, the condition is caused by a variety of mediators produced by cancer cells and cells in tumor microenvironments. Myostatin and activin signaling, IGF-1/PI3K/AKT signaling, and JAK-STAT signaling are known to play roles in cachexia, and thus, these pathways are considered potential therapeutic targets. This review discusses the current state of knowledge of the molecular mechanisms underlying cachexia and the available therapeutic options and was undertaken to increase understanding of the various factors/pathways/mediators involved and to identify potential treatment options.

Testicular morphometry of rats with Walker 256 tumor supplemented with L-glutamine

Glutamine is often used to treat metabolic changes associated with anorexia-cachexia syndrome in patients with malignant neoplasms. Walker 256 tumor is an excellent model for studying these changes associated with cancer in different organs, including injuries in testicular functions. However, the effects of supplementing glutamine on testicular morphometry in this model have not yet been investigated. Thus, the objective of this study was to evaluate the effect of L-glutamine supplementation on testicular morphometry in rats transplanted with Walker 256 tumor cells. Forty puberty Wistar rats were divided into four groups: control without L-glutamine (C); control supplemented with L-glutamine (CG); inoculated with Walker 256 tumor cells (WT) and inoculated with Walker 256 tumor cells and supplemented with L-glutamine (WTG). The testicles were removed, weighed, fixed in Bouin, and included in paraffin for histomorphometric analysis. Walker 256 tumor caused quantitative changes in the tubular and intertubular compartments and tunica albuginea, with reductions in the percentages of lumen and tunica albuginea, number of Sertoli cells per gram of testis; number of Leydig cells; percentage of blood vessels and connective tissue in intertubule. However, glutamine supplementation prevented part of these changes caused by the tumor, presenting mainly a protective effect on the tunica albuginea and percentage of blood and lymph vessels in the intertubule. These results indicate the potential of L-glutamine was able to recover for testicular dysfunction associated with cancer.

The mediation effect of serum metabolites on the relationship between long-term smoking exposure and esophageal squamous cell carcinoma

BACKGROUND

Long-term smoking exposure will increase the risk of esophageal squamous cell carcinoma (ESCC), whereas the mechanism is still unclear. We conducted a cross-sectional study to explore whether serum metabolites mediate the occurrence of ESCC caused by cigarette smoking.

METHODS

Serum metabolic profiles and lifestyle information of 464 participants were analyzed. Multiple logistic regression was used to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of smoking exposure to ESCC risk. High-dimensional mediation analysis and univariate mediation analysis were performed to screen potential intermediate metabolites of smoking exposure for ESCC.

RESULTS

Ever smoking was associated with a 3.11-fold increase of ESCC risk (OR = 3.11, 95% CI 1.63-6.05), and for each cigarette-years increase in smoking index, ESCC risk increased by 56% (OR = 1.56, 95% CI 1.18-2.13). A total of 5 metabolites were screened as mediators by high-dimensional mediation analysis. In addition, glutamine, histidine, and cholic acid were further proved existing mediation effects according to univariate mediation analysis. And the proportions of mediation of histidine and glutamine were 40.47 and 30.00%, respectively. The mediation effect of cholic acid was 8.98% according to the analysis of smoking index.

CONCLUSIONS

Our findings suggest that cigarette smoking contributed to incident ESCC, which may be mediated by glutamine, histidine and cholic acid.

Oral glutamine inhibits tumor growth of gastric cancer bearing mice by improving immune function and activating apoptosis pathway

Gastric cancer is one of the most common cancers in the world. It has been shown that exogenous glutamine (GLN) can inhibit the growth of tumor in vivo, but the relationship between GLN and gastric cancer has not been studied. The gastric cancer bearing mouse model was constructed and taken GLN orally at the same time, and the results found that oral GLN (1 or 2 g/kg/d) significantly inhibited the growth rate of tumor and reduce the weight of tumor tissues. Immunohistochemistry showed that oral GLN significantly reduced the PCNA index, which further proved that GLN could inhibit the growth of tumor cells. At the same time, TUNEL assay showed that oral GLN significantly enhanced the apoptosis levels of tumor cells. In addition, GLN reduced GSH levels in tumor tissues, but increased the levels of GSH in plasma, improved the T-lymphocyte transformation rate and NK cell activity, significantly inhibited the secretion of TNF-α and promoted the secretion of IL-2, thus regulating the immune function in vivo. Further detection of apoptosis pathway showed that oral GLN significantly enhanced the expression of pro-apoptotic factor Bad and inhibited the expression of Bcl-2. Meanwhile, GLN significantly increased the activities of Caspase-3, Caspase-8, caspase-9 and PARP. GSH activator NAC had a similar effect to GLN, which could improve the immune function and activate apoptosis pathway, while GSH inhibitor BSO significantly blocked the regulation of GLN, destroyed the immune balance and inhibited apoptosis, but IL-2 significantly blocked the anti-apoptotic effect of BSO. Therefore, oral GLN can improve immune function and activate apoptosis pathway through GSH, and then inhibit the growth of tumor in vivo.

Interorgan Metabolism of Amino Acids in Human Health and Disease

Amino acids are integral for human health, influencing an array of physiological processes from gene expression to vasodilation to the immune response. In accordance with this expansive range of unique functions, the tissues of the body engage in a complex interplay of amino acid exchange and metabolism to respond to the organism's dynamic needs for a range of nitrogenous products. Interorgan amino acid metabolism is required for numerous metabolic pathways, including the synthesis of functional amino acids like arginine, glutamate, glutamine, and glycine. This physiological process requires the cooperative handling of amino acids by organs (e.g., the small intestine, skeletal muscle, kidneys, and liver), as well as the complete catabolism of nutritionally essential amino acids such as the BCAAs, with their α-ketoacids shuttled from muscle to liver. These exchanges are made possible by several mechanisms, including organ location, as well as the functional zonation of enzymes and the cell-specific expression of amino acid transporters. The cooperative handling of amino acids between the various organs does not appear to be under the control of any centralized regulation, but is instead influenced by factors such as fluctuations in nutrient availability, hormones, changes associated with development, and altered environmental factors. While the normal function of these pathways is associated with health and homeostasis, affected by physical activity, diet and body composition, dysregulation is observed in numerous disease states, including cardiovascular disease and cancer cachexia, presenting potential avenues for the manipulation of amino acid consumption as part of the therapeutic approach to these conditions in individuals.

Novel Frontiers of Treatment for Advanced Gastric or Gastroesophageal Junction Cancer (GC/GEJC): Will Immunotherapy Be a Future Direction?

Considering the limited progress of chemotherapy and targeted therapy in improving the generally disappointing outcomes of advanced gastric or gastroesophageal junction cancer (GC/GEJC), immunotherapies have been gradually developed and advanced into novel frontiers of treatment for advanced GC/GEJC. Nevertheless, the response to immunotherapy was not always satisfactory, and the emergence of resistance was unavoidable. These factors prompt the development of different combination therapies and predictive and prognostic biomarkers of efficacy to improve the outcomes of patients with advanced GC/GEJC and to overcome drug resistance. This article discusses the advances of immune monotherapy, multiple current and ongoing clinical trials of immune combination therapy, immune-related adverse events, and various biomarkers in GC/GEJC.

Cancer cachexia and its pathophysiology: links with sarcopenia, anorexia and asthenia

Cancer cachexia is a multifactorial syndrome characterized by a progressive loss of skeletal muscle mass, along with adipose tissue wasting, systemic inflammation and other metabolic abnormalities leading to functional impairment. Cancer cachexia has long been recognized as a direct cause of complications in cancer patients, reducing quality of life and worsening disease outcomes. Some related conditions, like sarcopenia (age-related muscle wasting), anorexia (appetite loss) and asthenia (reduced muscular strength and fatigue), share some key features with cancer cachexia, such as weakness and systemic inflammation. Understanding the interplay and the differences between these conditions is critical to advance basic and translational research in this field, improving the accuracy of diagnosis and contributing to finally achieve effective therapies for affected patients.

Akt activation by insulin treatment attenuates cachexia in Walker-256 tumor-bearing rats

Cancer-bearing often exhibits hypoinsulinemia, insulin (INS) resistance and glutamine depletion associated with cachexia. However, INS and glutamine effects on cachexia metabolic abnormalities, particularly on tumor-affected proteins related to INS resistance, are poorly known. The main purpose of this study was to investigate the effects of INS and glutamine dipeptide (GDP) treatments on phospho-protein kinase B (p-Akt), and phospho-hormone sensitive lipase (p-HSL) in Walker-256 tumor-bearing rats. INS (NPH, 40 UI/kg, subcutaneous), GDP (1.5 g/kg, oral), INS+GDP or vehicle (control rats) were administered for 13 days, once a day, starting at the day of inoculation of tumor cells. The experiments were performed 4 hours after the last treatment to evaluate acute effects of INS and GDP, besides the chronic effects. INS and/or INS+GDP treatments, which markedly increased the insulinemia, increased the p-Akt: total Akt ratio and prevented the increased p-HSL^Ser552 : total HSL ratio in the retroperitoneal fat of tumor-bearing rats, without changing the INS resistance and increased expression of factor tumor necrosis-α (TNF-α) in this tissue. INS and INS+GDP also increased the p-Akt: total Akt ratio, whereas GDP and INS+GDP increased the GLUT4 glucose transporter gene expression, in the gastrocnemius muscle of the tumor-bearing rats. Accordingly, treatments with INS and INS+GDP markedly reduced glycemia, increased retroperitoneal fat and attenuated the body mass loss of tumor-bearing rats. In conclusion, hyperinsulinemia induced by high-dose INS treatments increased Akt phosphorylation and prevented increased p-HSL^Ser552 : total HSL ratio, overlapping INS resistance. These effects are consistent with increased fat mass gain and weight loss (cachexia) attenuation of tumor-bearing rats, evidencing that Akt activation is a potential strategy to prevent loss of fat mass in cancer cachexia.

The Role of Glutamine in the Complex Interaction between Gut Microbiota and Health: A Narrative Review

The scientific literature has demonstrated that glutamine is one of the main beneficial amino acids. It plays an important role in gut microbiota and immunity. This paper provides a critical overview of experimental studies (in vitro, in vivo, and clinical) investigating the efficacy of glutamine and its effect on gut microbiota. As a result of this review, we have summarized that glutamine could affect gut microbiota via different mechanisms including the reduction in the ratio of Firmicutes to Bacteroidetes, with the activation of NF-κB and PI3K-Akt pathways, reducing the intestinal colonization (Eimeria lesions) and bacterial overgrowth or bacterial translocation, increasing the production of secretory immunoglobulin A (SIgA) and immunoglobulin A+ (IgA+) cells in the intestinal lumen, and decreasing asparagine levels. The potential applications of glutamine on gut microbiota include, but are not limited to, the management of obesity, bacterial translocation and community, cytokines profiles, and the management of side effects during post-chemotherapy and constipation periods. Further studies and reviews are needed regarding the effects of glutamine supplementation on other conditions in humans.

Starve Cancer Cells of Glutamine: Break the Spell or Make a Hungry Monster?

Distinct from normal differentiated tissues, cancer cells reprogram nutrient uptake and utilization to accommodate their elevated demands for biosynthesis and energy production. A hallmark of these types of reprogramming is the increased utilization of, and dependency on glutamine, a nonessential amino acid, for cancer cell growth and survival. It is well-accepted that glutamine is a versatile biosynthetic substrate in cancer cells beyond its role as a proteinogenic amino acid. In addition, accumulating evidence suggests that glutamine metabolism is regulated by many factors, including tumor origin, oncogene/tumor suppressor status, epigenetic alternations and tumor microenvironment. However, despite the emerging understanding of why cancer cells depend on glutamine for growth and survival, the contribution of glutamine metabolism to tumor progression under physiological conditions is still under investigation, partially because the level of glutamine in the tumor environment is often found low. Since targeting glutamine acquisition and utilization has been proposed to be a new therapeutic strategy in cancer, it is central to understand how tumor cells respond and adapt to glutamine starvation for optimized therapeutic intervention. In this review, we first summarize the diverse usage of glutamine to support cancer cell growth and survival, and then focus our discussion on the influence of other nutrients on cancer cell adaptation to glutamine starvation as well as its implication in cancer therapy.

Randomized double-blind, placebo-controlled trial evaluating oral glutamine on radiation-induced oral mucositis and dermatitis in head and neck cancer patients

BACKGROUND

Glutamine is the primary fuel for the gastrointestinal epithelium and maintains the mucosal structure. Oncologists frequently encounter oral mucositis, which can cause unplanned breaks in radiotherapy (RT).

OBJECTIVES

The aim of this study was to explore the association between oral glutamine and acute toxicities in patients with head and neck cancer undergoing RT.

METHODS

This was a parallel, double-blind, randomized, placebo-controlled Phase III trial conducted in a university hospital. A central randomization center used computer-generated tables to allocate interventions to 71 patients with stages I-IV head and neck cancers. The patients, care providers, and investigators were blinded to the group assignment. Eligible patients received either oral glutamine (5 g glutamine and 10 g maltodextrin) or placebo (15 g maltodextrin) 3 times daily from 7 d before RT to 14 d after RT. The primary and secondary endpoints were radiation-induced oral mucositis and neck dermatitis, respectively. These were documented in agreement with the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.

RESULTS

The study included 64 patients (placebo n = 33; glutamine n = 31) who completed RT for the completers' analysis. Based on multivariate analysis, glutamine had no significant effect on the severity of oral mucositis (OR: 0.3; 95% CI: 0.05, 1.67; P = 0.169). Only the change in body mass index (BMI) was significant in both multivariate completers (OR: 0.41; 95% CI: 0.20, 0.84; P = 0.015) and per-protocol analysis (OR: 0.40; 95% CI: 0.20, 0.83; P = 0.014). No difference was found in the incidence and severity of neck dermatitis between the two arms.

CONCLUSIONS

The decrease in BMI was strongly related to the severity of oral mucositis in the head and neck cancer patients under RT, but not to the use of glutamine. This trial was registered at clinicaltrials.gov as NCT03015077.

Diet Modulation Restores Autophagic Flux in Damaged Skeletal Muscle Cells

OBJECTIVES

Autophagy is a physiological and highly regulated mechanism, crucial for cell homeostasis maintenance. Its impairment seems to be involved in the onset of several diseases, including muscular dystrophies, myopathies and sarcopenia. According to few papers, chemotherapeutic drug treatment is able to trigger side effects on skeletal muscle tissue and, among these, a defective autophagic activation, which leads to the persistence of abnormal organelles within cells and, finally, to myofiber degeneration. The aim of this work is to find a strategy, based on diet modulation, to prevent etoposide-induced damage, in a model of in vitro skeletal muscle cells.

METHODS

Glutamine supplementation and nutrient deprivation have been chosen as pre-treatments to counteract etoposide effect, a chemotherapeutic drug known to induce oxidative stress and cell death. Cell response has been evaluated by means of morpho-functional, cytofluorimetric and molecular analyses.

RESULTS

Etoposide treated cells, if compared to control, showed dysfunctional mitochondria presence, ER stress and lysosomal compartment damage, confirmed by molecular investigations.

CONCLUSIONS

Interestingly, both dietary approaches were able to rescue myofiber from etoposide-induced damage. Glutamine supplementation, in particular, seemed to be a good strategy to preserve cell ultrastructure and functionality, by preventing the autophagic impairment and partially restoring the normal lysosomal activity, thus maintaining skeletal muscle homeostasis.

A Pilot Study of Amino Acids in Unresectable Non-Small-Cell Lung Cancer Patients During Chemotherapy: A Randomized Serial N-of-1 Trials Design

The aim of this study was to evaluate the effect of amino acids (AAs) on immune function and inflammation level in patients with NSCLC receiving chemotherapy. We conducted a series of randomized, multiple-crossover, double-blind, placebo-controlled N-of-1 trials comparing AAs with isocaloric glucose in unresectable NSCLC patients and combined the individual results using Bayesian statistical modeling. 25 patients completed two cycles of chemotherapy. The baseline total blood albumin (ALB) level in all patients was 28 ± 3.3 g/l, and the mean total ALB level in patients receiving AAs supplementation and isocaloric glucose was 29.2 ± 2.2 and 28.1 ± 3.7 g/l, respectively (P = 0.028). Patients' baseline C-reactive protein (CRP) level was 4 ± 1.2 mg/l, the mean total CRP level in patients receiving AAs supplementation and isocaloric glucose was 11 ± 2.8 and 13 ± 3.2 mg/l, respectively (P = 0.028). The baseline total blood CD4⁺ T cells level was 36 ± 7.8%. The percentage of CD4⁺ T cells in patients receiving AAs supplementation and isocaloric glucose was 42 ± 6.4 and 33.7 ± 17.3, respectively (P = 0.034). Our preliminary results indicated that AAs improve immune status and suppress inflammation in unresectable NSCLC patients receiving chemotherapy.

Essential roles of mitochondrial and heme function in lung cancer bioenergetics and tumorigenesis

Contrary to Warburg’s hypothesis, mitochondrial oxidative phosphorylation (OXPHOS) contributes significantly to fueling cancer cells. Several recent studies have demonstrated that radiotherapy-resistant and chemotherapy-resistant cancer cells depend on OXPHOS for survival and progression. Several cancers exhibit an increased risk in association with heme intake. Mitochondria are widely known to carry out oxidative phosphorylation. In addition, mitochondria are also involved in heme synthesis. Heme serves as a prosthetic group for several proteins that constitute the complexes of mitochondrial electron transport chain. Therefore, heme plays a pivotal role in OXPHOS and oxygen consumption. Further, lung cancer cells exhibit heme accumulation and require heme for proliferation and invasion in vitro. Abnormalities in mitochondrial biogenesis and mutations are implicated in cancer. This review delves into mitochondrial OXPHOS and lesser explored area of heme metabolism in lung cancer.

Beta-Hydroxy-Beta-Methyl-Butyrate, L-glutamine, and L-arginine Supplementation Improves Radiation-Induce Acute Intestinal Toxicity

We aimed to evaluate effects of β-hydroxy-β-methylbutyrate, L-glutamine, and L-arginine (HMB/GLN/ARG) on radiation-induced acute intestinal toxicity. Forty rats were divided into four groups: group (G) 1 was defined as control group, and G2 was radiation therapy (RT) control group. G3 and G4 were HMB/GLN/ARG control and RT plus HMB/GLN/ARG groups, respectively. HMB/GLN/ARG started from day of RT and continued until the animals were sacrificed 10 days after RT. The extent of surface epithelium smoothing, villous atrophy, lamina propria inflammation, cryptitis, crypt distortion, regenerative atypia, vascular dilatation and congestion, and fibrosis were quantified on histological sections of intestinal mucosa. Statistical analyses were performed using the analysis of variance (ANOVA) test. There were significant differences between study groups regarding extent of surface epithelium smoothing, villous atrophy, lamina propria inflammation, cryptitis and crypt distortion, regenerative atypia, vascular dilatation and congestion, and fibrosis (p values were 0.019 for fibrosis, <.001 for the others). Pair-wise comparisons revealed significant differences regarding surface epithelium smoothing, villous atrophy, lamina propria inflammation, cryptitis, vascular dilatation, and congestion between G2 and G4 (p values were <.001, .033, <.001, .007, and <.001, respectively). Fibrosis score was significantly different only between G1 and G2 (p = .015). Immunohistochemical TGF-β score of G2 was significantly higher than G1 and G3 (p values were .006 and .017, respectively). There was no difference between TGF-β staining scores of G2 and G4. Concomitant use of HMB/GLN/ARG appears to ameliorate radiation-induced acute intestinal toxicity; however, this finding should be clarified with further studies.

Oral Glutamine Ameliorates Chemotherapy-induced Changes of Intestinal Permeability and Does not Interfere with the Antitumor Effect of Chemotherapy in Patients with Breast Cancer: A Prospective Randomized Trial

Aims and Background

Sixty patients with breast cancer were randomly assigned to oral glutamine or placebo pre-neoadju-vant chemotherapy (CEF regimen).

Methods and Study Design

Oral glutamine supplementation was continued for at least 12 days. Patients kept a daily record of diarrhea and stomatitis. The plasma glutamine level, intestinal permeability (lactulose-mannitol test), and tumor size were analyzed. The expression of Ki-67 and PCNA antigens in breast carcinoma was assessed.

Results

The plasma glutamine level was significantly higher in the glutamine group than in the placebo group (420.39 ± 52.39 mmol/L vs 309.76 ± 42.34 mmoi/L, P <0.05). After one cycle of chemotherapy, the lactulose-mannitol ratio was higher in the placebo group than in the glutamine group (0.0630 ± 0.0091 vs 0.0471 ± 0.0094, P <0.05). No differences were observed in the grades of stomatitis and diarrhea, in the changes in tumor size, and in the expression of Ki-67 and PCNA antigens between the two groups.

Conclusions

Prophylactic oral glutamine could ameliorate the neoadjuvant chemotherapy-induced increase in intestinal permeability, but had no significant positive clinical effect on stomatitis and diarrhea and did not interfere with the antitumor effect of chemotherapy.

Modulating Metabolism to Improve Cancer-Induced Muscle Wasting

Muscle wasting is one of the main features of cancer cachexia, a multifactorial syndrome frequently occurring in oncologic patients. The onset of cachexia is associated with reduced tolerance and response to antineoplastic treatments, eventually leading to clinical conditions that are not compatible with survival. Among the mechanisms underlying cachexia, protein and energy dysmetabolism play a major role. In this regard, several potential treatments have been proposed, mainly on the basis of promising results obtained in preclinical models. However, at present, no treatment yet reached validation to be used in the clinical practice, although several drugs are currently tested in clinical trials for their ability to improve muscle metabolism in cancer patients. Along this line, the results obtained in both experimental and clinical studies clearly show that cachexia can be effectively approached by a multidirectional strategy targeting nutrition, inflammation, catabolism, and inactivity at the same time. In the present study, approaches aimed to modulate muscle metabolism in cachexia will be reviewed.

Insulin, not glutamine dipeptide, reduces lipases expression and prevents fat wasting and weight loss in Walker 256 tumor-bearing rats

Cachexia is the main cause of mortality in advanced cancer patients. We investigated the effects of insulin (INS) and glutamine dipeptide (GDP), isolated or associated, on cachexia and metabolic changes induced by Walker 256 tumor in rats. INS (NPH, 40 UI/kg, sc) or GDP (1.5g/kg, oral gavage) was once-daily administered during 11 days after tumor cell inoculation. GDP, INS or INS+GDP treatments did not influence the tumor growth. However, INS and INS+GDP prevented retroperitoneal fat wasting and body weight loss of tumor-bearing rats. In consistency, INS and INS+GDP prevented the increased expression of triacylglycerol lipase (ATGL) and hormone sensitive lipase (HSL), without changing the expression of tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) in the retroperitoneal adipose tissue of tumor-bearing rats. INS and INS+GDP also prevented anorexia and hyperlactatemia of tumor-bearing rats. However, INS and INS+GDP accentuated the loss of muscle mass (gastrocnemius, soleus and long digital extensor) without affecting the myostatin expression in the gastrocnemius muscle and blood corticosterone. GDP treatment did not promote beneficial effects. It can be concluded that treatment with INS (INS or INS+GDP), not with GDP, prevented fat wasting and weight loss in tumor-bearing rats without reducing tumor growth. These effects might be attributed to the reduction of lipases expression (ATGL and LHS) and increased food intake. The results show the physiological function of INS in the suppression of lipolysis induced by cachexia mediators in tumor-bearing rats.

Lifestyle-Related Factors in the Self-Management of Chemotherapy-Induced Peripheral Neuropathy in Colorectal Cancer: A Systematic Review

Background. Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect of chemotherapy treatment in colorectal cancer (CRC), negatively affecting the daily functioning and quality of life of CRC patients. Currently, there are no established treatments to prevent or reduce CIPN. The purpose of this systematic review was to identify lifestyle-related factors that can aid in preventing or reducing CIPN, as such factors may promote self-management options for CRC patients suffering from CIPN. Methods. A literature search was conducted through PubMed, Embase, and Google Scholar. Original research articles investigating oxaliplatin-related CIPN in CRC were eligible for inclusion. Results. In total, 22 articles were included, which suggested that dietary supplements, such as antioxidants and herbal extracts, as well as physical exercise and complementary therapies, such as acupuncture, may have beneficial effects on preventing or reducing CIPN symptoms. However, many of the reviewed articles presented various limitations, including small sample sizes and heterogeneity in study design and measurements of CIPN. Conclusions. No strong conclusions can be drawn regarding the role of lifestyle-related factors in the management of CIPN in CRC patients. Certain dietary supplements and physical exercise may be beneficial for the management of CIPN, but further research is warranted.

Nutrition Modulation of Cachexia/Proteolysis

Cachexia represents progressive wasting of muscle and adipose tissue and is associated with increased morbidity and mortality. Although anorexia usually accompanies cachexia, cachexia rarely responds to increased food intake alone. Our knowledge of the underlying mechanisms responsible for cachexia remains incomplete. However, most states of cachexia are associated with underlying inflammatory processes and/or cancer. These processes activate protein degradation and lipolytic pathways, resulting in tissue loss. In this article, we briefly review the pathophysiology of cachexia and discuss the role of specific nutrient supplements for the treatment of cachexia. The branched chain amino acid leucine, the leucine metabolite beta-hydroxy-beta-methylbutyrate, arginine, glutamine, omega-3 long chain fatty acids, conjugated linoleic acid, and polyphenols have demonstrated some efficacy in animal and/or human studies. Optimal treatment for cachexia is likely aimed at maximizing muscle and adipose synthesis while minimizing degradation.

Outpatient Transfusion Practice and Factors Leading to Inpatient Transfusion in a Pediatric Hematology/Oncology Program

Oral mucositis continues to be a common and debilitating side effect of the conditioning regimens that use high-dose chemotherapy with or without radiation for pediatric bone marrow transplantation. Limited interventions have demonstrated success in preventing or treating it. Administration of glutamine, which is a nitrogen-rich amino acid found in the body, has emerged as a possible method of preventing oral mucositis in patients undergoing bone marrow transplantation. Numerous studies have looked at the effects of oral glutamine supplementation during bone marrow transplant. The purpose of this article is to describe glutamine and how it functions, review the literature regarding the use of oral glutamine in the prevention of oral mucositis in bone marrow transplantion, discuss the administration concerns related to the pediatric setting, and stress the importance of the nurse's role at the bedside. Nurses working in pediatric bone marrow transplant play a key role in the assessment of oral mucositis, administration of oral glutamine, and education of the patient and family.

The impact of glutamine supplementation on the symptoms of ataxia-telangiectasia: a preclinical assessment

BACKGROUND

Our previous studies of Alzheimer's disease (AD) suggested that glutamine broadly improves cellular readiness to respond to stress and acts as a neuroprotectant both in vitro and in AD mouse models. We now expand our studies to a second neurodegenerative disease, ataxia-telangiectasia (A-T). Unlike AD, where clinically significant cognitive decline does not typically occur before age 65, A-T symptoms appear in early childhood and are caused exclusively by mutations in the ATM (A-T mutated) gene.

RESULTS

Genetically ATM-deficient mice and wild type littermates were maintained with or without 4 % glutamine in their drinking water for several weeks. In ATM mutants, glutamine supplementation restored serum glutamine and glucose levels and reduced body weight loss. Lost neurophysiological function assessed through the magnitude of hippocampal long term potentiation was significantly restored. Glutamine supplemented mice also showed reduced thymus pathology and, remarkably, a full one-third extension of lifespan. In vitro assays revealed that ATM-deficient cells are more sensitive to glutamine deprivation, while supra-molar glutamine (8 mM) partially rescued the reduction of BDNF expression and HDAC4 nuclear translocation of genetically mutant Atm(-/-) neurons. Analysis of microarray data suggested that glutamine metabolism is significantly altered in human A-T brains as well.

CONCLUSION

Glutamine is a powerful part of an organism's internal environment. Changes in its concentrations can have a huge impact on the function of all organ systems, especially the brain. Glutamine supplementation thus bears consideration as a therapeutic strategy for the treatment of human A-T and perhaps other neurodegenerative diseases.

The effects of oral glutamine on clinical and survival outcomes of non-small cell lung cancer patients treated with chemoradiotherapy

PURPOSE

To assess the efficacy of oral glutamine (Gln) supplementation on clinical and survival outcomes of patients with locally advanced non-small cell lung cancer (LA-NSCLC).

MATERIALS/METHODS

Between 2010 and 2014, 122 stage III NSCLC patients were retrospectively analyzed. All patients received curative intent chemoradiotherapy (CRT). Prophylactic oral Gln powder was applied at a dose of 10 g tid. Effect of oral Gln supplementation in the prevention of severe (≥grade 2-3) acute radiation-induced esophagitis (ARE) and weight loss, and their relation with overall survival (OS) and disease-free survival (DFS) was measured.

RESULTS

Median follow-up was 13.14 months (range; 1.97-55.36). Fifty-six (46%) patients had received oral Gln. Severe ARE was significantly lower in Gln-supplemented group (30% vs 70%; p = 0.002). Gln-free patients demonstrated a higher weight loss (p = 0.0001). In multivariate analysis hemoglobin (hb) level (<12 g/dL; p = 0.01) and nodal stage (N3; p = 0.01) were poor prognostic factors that affect OS; Weight loss (p = 0.06) and Gln-free (p = 0.05) reached nearly significant levels that poorly affect OS. Similarly, nodal stage (N3, p = 0.014) and Gln-free (p = 0.035) were poor prognostic factors that affect DFS. Weight loss (≥2%, p = 0.06) and hb level (<12 g/dL, p = 0.07) reached borderline significance that poorly affect DFS. Nodal stage (N3) was the only poor prognostic factor that affect OS and DFS in univariate analysis (p = 0.01, p = 0.009; respectively).

CONCLUSION

Oral Gln supplementation significantly reduces grade 2-3 esophagitis and weight loss and also no negative impact on tumor control and survival outcomes in patients with LA-NSCLC.

Walker 256 tumor-bearing rats demonstrate altered interstitial cells of Cajal. Effects on ICC in the Walker 256 tumor model

BACKGROUND

Cachexia is a significant problem in patients with cancer. The effect of cancer on interstitial cells of Cajal (ICC) and neurons of the gastrointestinal tract have not been studied previously. Although supplementation with L-glutamine 2% may have beneficial effects in cancer-related cachexia, and be protective of ICC in models of oxidative stress such as diabetes, its effects on ICC in cancer have also not been studied.

METHODS

Twenty-eight male Wistar rats were divided into four groups: control (C), control supplemented with L-glutamine (CG), Walker 256 tumor (WT), and Walker 256 tumor supplemented with L-glutamine (WTG). Rats were implanted with tumor cells or injected with saline in the right flank. After 14 days, the jejunal tissues were collected and processed for immunohistochemical techniques including whole mounts and cryosections and Western blot analysis.

KEY RESULTS

Tumor-bearing rats demonstrate reduced numbers of Myenteric ICC and deep muscular plexus ICC and yet increased Ano1 protein expression and enhanced ICC networks. In addition, there is more nNOS protein expressed in tumor-bearing rats compared to controls. L-glutamine treatment had a variety of effects on ICC that may be related to the disease state and the interaction of ICC and nNOS neurons. Regardless, L-glutamine reduced the size of tumors and also tumor-induced cachexia that was not due to altered food intake.

CONCLUSIONS & INFERENCES

There are significant effects on ICC in the Walker 256 tumor model. Although supplementation with L-glutamine has differential and complex effects of ICC, it reduces tumor size and tumor-associated cachexia, which supports its beneficial therapeutic role in cancer.

Effect of glutamine enriched nutrition support on surgical patients with gastrointestinal tumor: a meta-analysis of randomized controlled trials

Background:

Associations between glutamine (Gln) enriched nutrition support and surgical patients with gastrointestinal (GI) tumor remain controversy. The purpose of this meta-analysis was to assess the effect of Gln enriched nutrition support on surgical patients with GI tumor in term of relevant biochemical indices, immune indices, and clinical outcomes.

Methods:

Six databases were systematically searched to find eligible randomized controlled trials (RCTs) from 1966 to May 2014. When estimated the analysis indexes, the relative risk (RR) was used as the effect size of the categorical variable, while the weighted mean difference (MD) was used as the effect size of a continuous variable. Meta-analysis was conducted with Rev Man 5.2.

Results:

Thirteen RCTs, involving 1034 patients, were included in the meta-analysis. The analysis showed that Gln enriched nutrition support was more effective in increasing serum albumin (MD: 0.10; 95% confidence interval [CI]: 0.02–0.18; P < 0.05), serum prealbumin (MD: 1.98; 95% CI: 1.40–2.55; P < 0.05) and serum transferring (MD: 0.35; 95% CI: 0.12–0.57; P < 0.05), concentration of IgG (MD: 1.26; 95% CI: 0.90–1.63; P < 0.05), IgM (MD: 0.18; 95% CI: 0.11–0.25; P < 0.05), IgA (MD: 0.22; 95% CI: 0.10–0.33; P < 0.05), CD3⁺ (MD: 3.71; 95% CI: 2.57–4.85; P < 0.05) and CD4/CD8 ratio (MD: 0.27; 95% CI: 0.12–0.42; P < 0.05). Meanwhile, it was more significant in decreasing the incidence of infectious complications (RR: 0.67; 95% CI: 0.50–0.90; P < 0.05) and shortening the length of hospital stay (MD: −1.72; 95% CI: −3.31–−0.13; P < 0.05).

Conclusions:

Glutamine enriched nutrition support was superior in improving immune function, reducing the incidence of infectious complications and shortening the length of hospital stay, playing an important role in the rehabilitation of surgical GI cancer patients.

The role of glutamine supplementation in thoracic and upper aerodigestive malignancies

In cancer patients, marked glutamine (gln) depletion develops over time. Host tissues (epithelial cells and lymphocytes) that depend upon adequate stores of gln for optimal functioning can be negatively influenced. In addition, radiation and/or chemotherapy cause normal tissues damage that might be enhanced by this depletion effect. The present review evaluates in vivo clinical data about the potential beneficial role of gln administration in the prevention of host tissue toxicity, in a patient group with thoracic and upper aerodigestive malignancies (T&UAM) during cancer treatment. Publications were identified in a systematic review of MEDLINE Database from the last 2 decades (1994-2014) using key search terms and through manual searches. Overall, 13 clinical studies (9 oral/4 parenteral) evaluated the safety and tolerance of gln supply, showing a beneficial effect in the grade, duration of mucositis and esophagitis, decreased gut permeability, and weight loss. Only 1 Phase 1 clinical trial had negative results because the chemo-radiotherapy combined treatment was not feasible. The use of oral gln may especially have an important role in the prevention of acute radiation toxicities, the weight loss and the need for analgesics in patients with T&UAM, especially if the treatment plan includes combined modality therapy with chemo-radiation.

Is glutamine deficiency the link between inflammation, malnutrition, and fatigue in cancer patients?

PURPOSE

Evaluation of potential associations between plasma glutamine levels and the incidence of cancer related fatigue, physical performance, poor nutritional status, and inflammation in patients with solid tumors.

STUDY DESIGN

Mono-center cross-sectional study recruiting 100 (34 women) consecutive patients (September 2009-March 2011; ≥18 y) with solid tumors and causal tumor therapy.

METHODOLOGY

Fasting venous blood was harvested for routine clinical chemistry, amino acid (HPLC) and inflammation marker analyses. Clinical assessments included global, physical, affective and cognitive fatigue (questionnaire) and Karnofsky performance status. Nutritional status was evaluated using bioelectrical impedance analysis, the Prognostic Inflammatory and Nutritional Index and plasma protein levels. Regression analyses were performed to correlate continuous variables with plasma glutamine (95% confidence intervals).

RESULTS

Nutritional status was impaired in 19% of the patients. Average plasma glutamine concentration (574.0 ± 189.6 μmol/L) was within normal range but decreased with impaired physical function. Plasma glutamine was linked to the ratio extracellular to body cell mass (p < 0.044), CRP (p < 0.001), physical (p = 0.014), affective (p = 0.041), and global fatigue (p = 0.030). Markers of inflammation increased with low physical performance.

CONCLUSIONS

The data support our working hypothesis that in cancer patients systemic inflammation maintains a catabolic situation leading to malnutrition symptoms and glutamine deprivation, the latter being associated with cancer related fatigue.

Parenteral glutamine supplementation has no effect on chemotherapy-induced toxicity in children with non-Hodgkin lymphoma

PURPOSE

Protecting patients from the acute and/or chronic toxicity of antineoplastic therapy has become a major concern of oncology centers around the world. Glutamine has been used as a multisystemic protective agent to minimize the side effects arising from the treatment of childhood cancers. In this study, the effect of intravenous glutamine supplementation was investigated in children receiving chemotherapy for non-Hodgkin lymphoma.

METHODS

Twelve children, of 48 to 120 months of age, and who had non-Hodgkin lymphoma were enrolled in the study. Thirty chemotherapy courses were given in combination with glutamine, and 31 chemotherapy courses were given without glutamine. Glutamine was given intravenously for 7 days, at a dose of 0.4 g/kg/d. Patients were evaluated in each course with regard to gastrointestinal, mucosal, and hematological toxicities.

RESULTS

There were no significant differences in the hematological parameters between the 2 groups. The requirements for red blood cells and platelets during the chemotherapy courses were similar in both groups (P=0.64 and 0.40, respectively). Patients supplemented with glutamine developed mucositis in 21 of 30 courses (70%) and patients without glutamine supplements developed mucositis in 23 of 31 courses (74%). The mean duration of mucositis and the mean mucositis score in each course were similar between the 2 groups. In addition, gastrointestinal system and hepatic toxicity did not differ between groups. The mean duration of febrile neutropenia and the length of hospitalization were also similar in both groups (P=0.09 and 0.13, respectively).

CONCLUSIONS

Parenteral glutamine supplementation has no effect on mucositis, fever and febrile neutropenia, length of hospitalization, red blood cell, and platelet requirements, and hematological, gastrointestinal, and hepatic toxicities in children receiving severe chemotherapy.

Amelioration of radiation-induced acute inflammation and mucosal atrophy by beta-hydroxy-beta-methylbutyrate, L-glutamıne, and L-argınıne: results of an experimental study

PURPOSE

We aimed to evaluate the effects of β-hydroxy-β-methylbutyrate, L-glutamine, and L-arginine (HMB/Glu/Arg) on radiation-induced acute inflammation and mucosal atrophy in the oral mucosa.

METHODS

Twenty-eight rats were divided into four groups. group (G) 1 was defined as control group, and G2 was the radiation therapy (RT) group. G3 and G4 were HMB/Glu/Arg control and 17 Gy RT plus HMB/Glu/Arg groups, respectively. A single dose of 17 Gy RT was given to the head and neck area, and the active supplement consisting of 5.2 g of HMB, 29.6 g arginine, and 29.6 g of glutamine which was equivalent to 60 kg adult dose was calculated for each rat and administrated orally. HMB/Glu/Arg started from the day of RT and continued until the animals were sacrificed 7 days after the RT. The extent of acute inflammation and mucosal atrophy for each rat was quantified with image analysis of histological sections of the oral mucosa.

RESULTS

There were significant differences in terms of epithelial thickness, subepithelial edema, inflammation, and congestion between all groups (p values were <0.001, 0.003, <0.001, and 0.001 for each parameter, respectively). Using HMB/Glu/Arg alone led to hypertrophic changes in the epithelial layer. Moreover, when used with RT, HMB/Glu/Arg reversed radiation-induced epithelial atrophy (p, 0.006) and decreased radiation-induced inflammation at a significant level (p, 0.007).

CONCLUSION

Concomitant use of HMB/Glu/Arg appears to ameliorate the radiation-induced acute inflammation and mucosal atrophy which represent the early phase of acute oral mucositis; however, this finding should be clarified with further clinical studies.

Light aerobic physical exercise in combination with leucine and/or glutamine-rich diet can improve the body composition and muscle protein metabolism in young tumor-bearing rats

Nutritional supplementation with some amino acids may influence host's responses and also certain mechanism involved in tumor progression. It is known that exercise influences body weight and muscle composition. Previous findings from our group have shown that leucine has beneficial effects on protein composition in cachectic rat model as the Walker 256 tumor. The main purpose of this study was to analyze the effects of light exercise and leucine and/or glutamine-rich diet in body composition and skeletal muscle protein synthesis and degradation in young tumor-bearing rats. Walker tumor-bearing rats were subjected to light aerobic exercise (swimming 30 min/day) and fed a leucine-rich (3%) and/or glutamine-rich (4%) diet for 10 days and compared to healthy young rats. The carcasses were analyzed as total water and fat body content and lean body mass. The gastrocnemious muscles were isolated and used for determination of total protein synthesis and degradation. The chemical body composition changed with tumor growth, increasing body water and reducing body fat content and total body nitrogen. After tumor growth, the muscle protein metabolism was impaired, showing that the muscle protein synthesis was also reduced and the protein degradation process was increased in the gastrocnemius muscle of exercised rats. Although short-term exercise (10 days) alone did not produce beneficial effects that would reduce tumor damage, host protein metabolism was improved when exercise was combined with a leucine-rich diet. Only total carcass nitrogen and protein were recovered by a glutamine-rich diet. Exercise, in combination with an amino acid-rich diet, in particular, leucine, had effects beyond reducing tumoral weight such as improving protein turnover and carcass nitrogen content in the tumor-bearing host.

Nutritional effect of oral supplement enriched in beta-hydroxy-beta-methylbutyrate, glutamine and arginine on resting metabolic rate after laparoscopic gastric bypass

BACKGROUND

Weight regain that begins 12-18 months after laparoscopic gastric bypass has been attributed to changes in resting metabolic rate (RMR), which is largely determined by lean body mass (LBM). An oral supplement containing beta-hydroxy-beta-methylbutyrate, glutamine, and arginine (HMB/Glu/Arg) has helped to restore LBM in cachexia due to cancer and in critically ill trauma patients. The objective of this study was to evaluate the effect of oral HMB/Glu/Arg on LBM and RMR following laparoscopic gastric bypass (LGB).

METHODS

Patients who underwent LGB were randomized to receive 24 g of HMB/Glu/Arg dissolved in water twice daily for 8 weeks or to receive no supplement. Weight loss, LBM, and RMR were assessed preoperatively, 2 and 8 weeks postoperatively. LBM was determined by dual emission x-ray absorptiometry (DXA) and RMR was measured by indirect calorimetry.

RESULTS

Thirty patients were enrolled: 80% white; 20% African American; 96.7% women; mean age 46.9±8.4 years; mean weight 113.4±11.6 kg; and mean body mass index (BMI) 43.3±4.1 kg/m2. The experimental and control groups included 14 and 16 patients, respectively, and there was no difference in baseline demographics and characteristics between the two groups. At 8 weeks, weight, BMI, LBM, and RMR significantly decreased by 15.7±2.5 kg, 6.0±1.0 kg/m2, 7.8±4.0 kg, and 290.6±234.9 kcal/day, respectively (P<0.0001 for each variable). However, when comparing these changes between the two groups, no statistical significance was observed.

CONCLUSIONS

There is a significant decrease in weight, BMI, LBM, and RMR in all subjects after LGB, and these changes were not affected by the use of HMB/Glu/Arg. Potential preservation of LBM as a result of HMB/Glu/Arg requires further investigation. However, its consumption (78 calories per serving) did not adversely affect weight loss in the experimental group.

L-Glutamine Use in the Treatment and Prevention of Mucositis and Cachexia: A Naturopathic Perspective

L-Glutamine (L-GLN) is considered a nonessential amino acid that has a variety of applications in naturopathic medicine. It has been postulated that in the critically ill patient, GLN becomes an essential amino acid for recovery, restoration, and repair at a cellular level. Mucositis is an intestinal mucosal damage of the gastrointestinal tract—mouth, throat, stomach, intestines, rectum, and anus—that is caused directly by chemotherapies and radiotherapies. Cancer cachexia is a significant biochemical event, which is characterized by weight loss, fatigue, and indicative of depletion of skeletal muscle GLN—a hypercatabolic state. There has been some question as to the use of GLN in this patient population because of its role as a preferred energy source not only for enterocytes and lymphocytes but for malignant cells as well.This article will address the questions of safety, efficacy, dosing, and toxicity of GLN used as an integrative therapeutic in ongoing integrative cancer treatment.

Clinical trial: prophylactic intravenous alanyl-glutamine reduces the severity of gastrointestinal toxicity induced by chemotherapy--a randomized crossover study

BACKGROUND

Glutamine has been shown in numerous studies to reduce intestinal permeability which can be increased by chemotherapy. However, there have been few reports that conduct on its clinical effect on gastrointestinal toxicity.

AIM

To examine whether prophylactic intravenous alanyl-glutamine dipeptide can ameliorate clinical manifestations of gastrointestinal toxicity induced by chemotherapy.

METHODS

Forty-four patients with gastric or colorectal cancer developing WHO side-effect grading system of grade 2 or higher were randomized to either control group (n = 22) or Gln group (n = 22) during next cycle of chemotherapy. Patients were crossed over to the alternate treatment during chemotherapy cycle 2. In the control group, the patients received the same chemotherapy regimens as screening cycle and in the Gln group, the patients received chemotherapy and alanyl-glutamine. Prophylactic intravenous 20 g of alanyl-glutamine dipeptide was given for 5 days.

RESULTS

Compared with the control group, the plasma glutamine level in the Gln group was significantly higher and the plasma endotoxin level was significantly lower. The scores of nausea/vomiting and diarrhoea decreased significantly.

CONCLUSION

Prophylactic intravenous alanyl-glutamine is effective in preventing intestinal permeability disruption induced by chemotherapy and clinical manifestations of gastrointestinal toxicity.

Effect of glutamine on gut glutathione fractional release in the implanted tumor model

Cancer and its treatments cause a marked depletion of glutamine (GLN). However, dietary GLN can restore this loss and improve the outcomes of the treatments. The reasons behind this need to be investigated. GLN is suggested to involve in glutathione (GSH) synthesis. Fast-growing tumors alter gut GLN metabolism, but the effect of tumor growth on gut GSH release remains unknown. We hypothesized that gut GSH release would decrease in the tumor-bearing host and this downregulation would be antagonized by supplemental GLN. Female Fisher-344 rats were randomized to the groups: GLN + TUMOR, Freamine (FA) + TUMOR, GLN + SHAM, and FA + SHAM. The rats were implanted with MTF-7 mammary tumors as tumor-bearing groups, whereas the rats were sham operated as control groups. The rats were pair fed chow, gavaged with 1 g/kg/day GLN or an isonitrogenous FA. Tumor growth, blood and gut mucosa GLN, glutamate, and/or GSH were measured. The gut extractions, defined as the difference of concentrations across the gut, were calculated. Supplemental GLN enhanced the gut GLN uptake and GSH release with tumor growth and significantly increased blood and gut mucosa GLN and/or GSH concentrations. Our results demonstrate the important antioxidant role of GLN and thus may have significant implications in nutritional immune modulation in cancer patients.

The role of oral glutamine in pediatric bone marrow transplant

Oral mucositis continues to be a common and debilitating side effect of the conditioning regimens that use high-dose chemotherapy with or without radiation for pediatric bone marrow transplantation. Limited interventions have demonstrated success in preventing or treating it. Administration of glutamine, which is a nitrogen-rich amino acid found in the body, has emerged as a possible method of preventing oral mucositis in patients undergoing bone marrow transplantation. Numerous studies have looked at the effects of oral glutamine supplementation during bone marrow transplant. The purpose of this article is to describe glutamine and how it functions, review the literature regarding the use of oral glutamine in the prevention of oral mucositis in bone marrow transplantion, discuss the administration concerns related to the pediatric setting, and stress the importance of the nurse's role at the bedside. Nurses working in pediatric bone marrow transplant play a key role in the assessment of oral mucositis, administration of oral glutamine, and education of the patient and family.