Carr Anitra C, Vlasiuk Emma, Zawari Masuma, Meijer Natalie, Lauren Carolyn, MacPherson Sean, Williman Jonathan, Chambers Stephen T
Nutrition in Medicine Research Group, Department of Pathology and Biomedical Science, University of Otago, Christchurch 8011, New Zealand.
Department of Haematology, Christchurch Hospital, Christchurch 8011, New Zealand.
Antioxidants (Basel). 2022 Sep 29;11(10):1949. doi: 10.3390/antiox11101949.
Chemotherapy-related side effects are common in patients undergoing myeloablative chemotherapy and haematopoietic stem cell transplantation. Some, such as oral mucositis, are believed to be due to enhanced oxidative stress and inflammation. Vitamin C, a potent antioxidant with anti-inflammatory properties, becomes severely depleted following myeloablative chemotherapy. The aim of our study was to assess the feasibility and efficacy of oral vitamin C supplementation to restore and maintain adequate vitamin C concentrations in patients undergoing myeloablative chemotherapy and stem cell transplantation. We carried out a pilot randomized controlled trial in 20 patients with myeloma and lymphoma. Placebo or vitamin C tablets (1 g twice daily) were initiated one week prior to transplantation and continued for 4 weeks post-transplantation. Blood samples were collected weekly for analysis of plasma vitamin C concentrations using high-performance liquid chromatography. The patients' symptoms and quality of life parameters were monitored using the World Health Organization oral toxicity scale and the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ). Pre-supplementation with oral vitamin C doubled vitamin C concentrations relative to placebo by day 0 (median 61 vs. 31 µmol/L), with 60% of those in the vitamin C group achieving concentrations ≥ 50 µmol/L, compared with only 10% in the placebo group. Following chemotherapy and transplantation, significance between the vitamin C and placebo groups was lost by day 7, with only 30% of the patients in the vitamin C group having plasma concentrations ≥ 50 µmol/L. This was partly due to intolerance of the oral intervention due to nausea/vomiting and diarrhoea (40% of the participants in each group). Oral mucositis was also observed in 40% of the participants at day 7 or 14. Overall, our study showed that whilst short-term oral vitamin C pre-supplementation was able to restore adequate vitamin C status by day 0, ongoing supplementation could not maintain adequate vitamin C concentrations following chemotherapy and transplantation. Thus, intravenous vitamin C should be trialled as this bypasses the gastrointestinal system, negating intolerance issues and improving bioavailability of the vitamin.
化疗相关的副作用在接受清髓性化疗和造血干细胞移植的患者中很常见。其中一些副作用，如口腔黏膜炎，被认为是由于氧化应激和炎症增强所致。维生素C是一种具有抗炎特性的强效抗氧化剂，在清髓性化疗后会严重缺乏。我们研究的目的是评估口服补充维生素C以恢复和维持接受清髓性化疗和干细胞移植患者体内维生素C充足浓度的可行性和疗效。我们对20例骨髓瘤和淋巴瘤患者进行了一项初步随机对照试验。在移植前一周开始服用安慰剂或维生素C片（每日两次，每次1克），并在移植后持续服用4周。每周采集血样，使用高效液相色谱法分析血浆维生素C浓度。使用世界卫生组织口腔毒性量表和欧洲癌症研究与治疗组织生活质量问卷（EORTC QLQ）监测患者的症状和生活质量参数。在第0天，口服维生素C预补充使维生素C浓度相对于安慰剂增加了一倍（中位数分别为61 vs. 31 μmol/L），维生素C组中有60%的患者达到≥50 μmol/L的浓度，而安慰剂组中只有10%。化疗和移植后，到第7天维生素C组和安慰剂组之间的差异消失，维生素C组中只有30%的患者血浆浓度≥50 μmol/L。这部分是由于恶心/呕吐和腹泻导致对口服干预不耐受（每组40%的参与者）。在第7天或第14天，40%的参与者也出现了口腔黏膜炎。总体而言，我们的研究表明，虽然短期口服维生素C预补充能够在第0天恢复充足的维生素C状态，但化疗和移植后持续补充无法维持充足的维生素C浓度。因此，应尝试静脉注射维生素C，因为这绕过了胃肠道系统，消除了不耐受问题并提高了维生素的生物利用度。
