1.
The role of adjuvant probiotics to attenuate intestinal inflammatory responses due to cancer treatments.
Thomsen, M, Clarke, S, Vitetta, L
Beneficial microbes. 2018;(6):899-916
Abstract
Chemotherapy and radiotherapy treatment regimens for gastrointestinal, peritoneal and pelvic tumours can disrupt the intestinal microbiome and intestinal epithelia. Such disturbances can provoke symptoms such as diarrhoea, nausea and vomiting. Chemotherapy and radiotherapy induced gastrointestinal toxicity aggravating intestinal microbiome dysbiosis is postulated to adversely alter the intestinal microbiome, with a consequent induced pro-inflammatory effect that disrupts the intestinal microbiome-epithelia-mucosal immunity axis. Although not widely recognised, the intestinal mucosa is the largest and most densely and dynamically populated immune-environment. Cancer treatment adverse effects that affect intestinal and mucosal cells inadvertently target and disrupt resident intestinal macrophages, the cells that marshal immune activity in the intestinal mucosa by shaping pro-inflammatory and anti-inflammatory activities to control and eradicate infectious insults and maintain local homeostasis. Pathobionts (bacteria capable of pathogenic pro-inflammatory activity) and noxious environmental and bacterial antigens use the intestinal epithelia and gap junctions as a point of entry into the systemic circulation. This translocation movement promotes toxic sequelae that obstruct intestinal macrophage functions resulting in uncontrolled local and systemic pro-inflammatory activity, loss of phagocytic function and loss of expression of tight junction proteins. Probiotic bacteria as an adjunctive treatment shows efficacy in ameliorating enteropathies such as mucositis/diarrhoea resulting from chemotherapy or radiotherapy regimens. As such we posit that an important benefit that warrants a further focused research effort is the administration of adjuvant probiotics to help reduce the incidence of febrile neutropenia.
2.
Efficacy of glutamine in the prevention of acute radiation enteritis: a randomized controlled trial.
Vidal-Casariego, A, Calleja-Fernández, A, de Urbina-González, JJ, Cano-Rodríguez, I, Cordido, F, Ballesteros-Pomar, MD
JPEN. Journal of parenteral and enteral nutrition. 2014;(2):205-13
Abstract
BACKGROUND Acute radiation enteritis is a common adverse effect related to radiotherapy (RT). Glutamine is an immune modulator and antioxidant amino acid that can exert a protective role in patients receiving abdominal or pelvic radiation. The aim of this study was to test if glutamine prevents radiation enteritis during RT. MATERIALS AND METHODS Double-blind, randomized, controlled trial including 69 patients who needed RT because of pelvic or abdominal malignancies and received glutamine (30 g/d) or placebo (casein, 30 g/d). Enteritis was evaluated according to the Radiation Therapy Oncology Group scale, intestinal inflammation using fecal calprotectin, and gut integrity with citrulline. The incidence of enteritis was analyzed by Kaplan-Meier curves, and the hazard ratio (HR) was calculated using Cox regression. RESULTS Patients were predominantly male (65.2%), with an average (SD) age of 66.6 (9.9) years, with urologic (44.9%), rectal (24.6%), or gynecological cancer (23.1%). More patients developed enteritis with glutamine than with the placebo (55.9% vs 22.0%; P = .002), with an HR OF 1.59 (95% confidence interval, 0.624.05). There were no differences in final calprotectin levels (glutamine, 57.9 [85.8] mg/kg vs placebo, 54.0 [57.7] mg/kg; p = .182) or the number of patients with values 50 mg/kg (glutamine, 58.1% vs placebo, 54.6%; p = .777). Final citrulline levels were similar between groups (glutamine, 26.31 [10.29] mmol/l vs placebo, 27.69 [12.31] mmol/l; p = .639), without differences in the number of patients with 20 mmol/l (glutamine, 24.1% vs placebo, 25.0%; P = .938). Citrulline concentration was reduced during rt with placebo but remained unchanged with glutamine. CONCLUSION Glutamine does not prevent the development of enteritis during RT.