Peterson Kristine M, O'Shea Marianne, Stam Wiro, Mohede Inge C M, Patrie James T, Hayden Frederick G
Department of Internal Medicine, University of Virginia, Charlottesville, VA, USA.
Antivir Ther. 2009;14(1):33-43.
Because studies suggest that the dietary supplement conjugated linoleic acid (CLA) has immunomodulatory activities that might benefit common colds, we performed two studies of CLA effects in experimental human rhinovirus (HRV) infection.
The first study explored whether CLA supplementation (Safflorin; Loders Croklaan, BV, Wormerveer, the Netherlands) altered the virological or clinical course of experimental HRV infection, and the second explored whether CLA affected the frequency and severity of HRV cold-associated sore throat and cough. The trials were randomized, double-blinded and placebo-controlled. In total, 50 healthy volunteers aged 18-45 years and susceptible to HRV type-39 (serum neutralizing antibody titre < or = 1:2) participated in study 1 and 80 similar volunteers susceptible to Hank's HRV participated in study 2. Participants ingested CLA 2 g/day or placebo for 4 weeks before and 4 days following intranasal HRV inoculation. The primary endpoint for study 1 was the frequency of colds and for study 2 was the symptom severity scores for sore throat and cough.
In study 1, 10/24 (42%) placebo compared with 7/21 (33%) CLA participants developed colds (P = 0.53). CLA was associated with significant reductions in mean scores for cough (0 CLA versus 0.9 placebo) and sore throat (0.8 CLA versus 2.9 placebo). In study 2, clinical colds developed in 19/33 (58%) placebo and 27/43 (63%) CLA participants. Symptom scores for cough (0.9 CLA versus 1.0 placebo) and sore throat (2.6 CLA versus 3.2 placebo) were not significantly different. Similarly no differences in nasal viral titres or serological responses were found.
CLA dietary supplementation had no consistent effects on the virological or clinical course of experimental HRV colds. A larger study would be required to detect more subtle effects of CLA on HRV cold-associated symptoms.
由于研究表明膳食补充剂共轭亚油酸（CLA）具有免疫调节活性，可能对普通感冒有益，我们进行了两项关于CLA对实验性人鼻病毒（HRV）感染影响的研究。
第一项研究探讨补充CLA（Safflorin；荷兰沃默弗尔的洛德斯·克罗克兰公司）是否会改变实验性HRV感染的病毒学或临床病程，第二项研究探讨CLA是否会影响HRV感冒相关喉咙痛和咳嗽的频率及严重程度。试验为随机、双盲和安慰剂对照。共有50名年龄在18至45岁、易感染39型HRV（血清中和抗体滴度≤1:2）的健康志愿者参与研究1，80名类似的易感染汉克HRV的志愿者参与研究2。参与者在经鼻接种HRV前4周和接种后4天每天摄入2克CLA或安慰剂。研究1的主要终点是感冒频率，研究2的主要终点是喉咙痛和咳嗽的症状严重程度评分。
在研究1中，安慰剂组24人中有10人（42%）患感冒，而CLA组21人中有7人（33%）患感冒（P = 0.53）。CLA与咳嗽平均评分（CLA组为0，安慰剂组为0.9）和喉咙痛平均评分（CLA组为0.8，安慰剂组为2.9）的显著降低相关。在研究2中，安慰剂组33人中有19人（58%）出现临床感冒，CLA组43人中有27人（63%）出现临床感冒。咳嗽（CLA组为0.9，安慰剂组为1.0）和喉咙痛（CLA组为2.6，安慰剂组为3.2）的症状评分无显著差异。同样，在鼻腔病毒滴度或血清学反应方面也未发现差异。
膳食补充CLA对实验性HRV感冒的病毒学或临床病程没有一致的影响。需要进行更大规模的研究来检测CLA对HRV感冒相关症状的更细微影响。
