Supplementation with antioxidant micronutrients and chemotherapy-induced toxicity in cancer patients treated with cisplatin-based chemotherapy: a randomised, double-blind, placebo-controlled study.

Cisplatin-induced toxicities are mainly caused by the formation of free radicals, leading to oxidative organ damage. Plasma concentrations of antioxidants decrease significantly during cisplatin chemotherapy for cancer. Forty-eight cancer patients treated with cisplatin-based chemotherapy were randomised in a double-blind manner to receive either supplementation with vitamin C, vitamin E and selenium dissolved in a beverage or to receive a placebo beverage. Primary outcome measures were the amount of nephrotoxicity and ototoxicity induced by cisplatin. No significant differences were found between the two study groups with respect to these primary outcome measures. However, patients who achieved the highest plasma concentrations of the three antioxidant micronutrients had significantly less loss of high-tone hearing. In addition, significant correlations were found between the reduced/oxidised vitamin C ratio and malondialdehyde (MDA), markers of oxidative stress, and cisplatin-induced ototoxicity and nephrotoxicity. The lack of protection against cisplatin-induced toxicities in patients in the intervention arm may be related to poor compliance and/or inadequate supplementation. Supplementation with a higher dose (intensity) and in combination with other antioxidants should be investigated further.

Cisplatin combination chemotherapy induces a fall in plasma antioxidants of cancer patients.

BACKGROUND: Antioxidants protect the body against cellular oxidative damage and thus some of the adverse effects induced by cisplatin and other cytostatic drugs. PATIENTS AND METHODS: The effect of cisplatin-combination chemotherapy on concentrations of plasma antioxidants was studied in 36 cancer patients, including osteosarcoma and testicular carcinoma patients. RESULTS: Eight to 15 days after the start of each cytostatic drug infusion concentrations of various plasma antioxidants were measured and compared to pretreatment values: vitamin C and E, uric acid and ceruloplasmin levels fell significantly (P < 0.01-0.005) and returned to baseline levels before the start of the next chemotherapy cycle. Levels of the antioxidants bilirubin albumin and the ratio vitamin E/cholesterol + triglycerides measured three weeks after the start of chemotherapy significantly decreased compared to pretreatment levels and remained low thereafter (P < 0.001-0.002). Dietary intake of antioxidants and anthropometric measurements, evaluated in 14 patients did not change during the whole treatment period. CONCLUSIONS: Cisplatin-combination chemotherapy induces a fall in plasma antioxidant levels, that may reflect a failure of the antioxidant defense mechanism against oxidative damage induced by commonly used anticancer drugs. This probably results from consumption of antioxidants caused by chemotherapy induced-oxidative stress as well as renal loss of water-soluble, small molecular weight antioxidants such as uric acid.

[Diabetic gastroparesis: is tube feeding an alternative?]. / Diabetische gastroparese: is sondevoeding een alternatief?

A woman aged 26 with long-standing insulin-dependent diabetes mellitus displayed recurrent periods of nausea, vomiting, abnormal blood sugar levels, weight loss and poor physical condition in spite of a diet and use of propulsive agents. Scintigraphy revealed decelerated gastric evacuation for solid and liquid nutrients. The patient recovered after insertion of a percutaneous endoscopic gastrostomy (PEG) catheter. Diabetic gastroparesis is associated with a vicious circle in which delayed gastric emptying leads to poor glucose regulation with frequent hyperglycaemia, which in its turn adversely affects gastric emptying. Treatment should be aimed at improvement of the gastric motility (for instance by propulsive agents), more accurate glucose regulation and nutritional counselling. If this fails to produce improvement, tube feeding via a permanent nasoduodenal tube or via a PEG catheter constitutes an acceptable alternative for oral nutrition.

Effect of gluten supplementation in healthy siblings of children with celiac disease.

The clinical, functional, and histopathological effects of 18 g additional gluten intake daily for 4 wk was studied in 13 healthy siblings of Spanish children with celiac disease, including two pairs of discordant monozygotic twins. Five of the 13 children were HLA-DR identical to the celiac sibling, 5 shared only one HLA-DR antigen with the celiac sibling, and 3 had completely different HLA-DR antigens than their respective celiac brothers or sisters. Clinical evaluation and functional tests (routine blood, xylose absorption, and fecal fat excretion studies) were performed before, during, and after gluten challenge. A jejunal biopsy specimen was taken at the end of the 4-wk period of gluten supplementation. No clinical abnormalities were found during the period of the study and there was no significant decrease of xylose absorption. Fecal fat excretion studies gave normal results, both before and after gluten challenge. The high gluten diet did not lead to histopathologic abnormalities in any of the jejunal biopsy specimens, which showed a normal range of crypt to villus ratio and surface-cell height. The present results do not support the view that excessive gluten intake is toxic for individuals who are genetically predisposed but do not have overt celiac disease. The findings also suggest that other factors besides HLA-DR antigens and gluten intake are important for expression of the disease.