GASTROENTEROLOGY：益生菌摄入或可影响大脑活性

　　美国一项研究表明，在健康女性中，益生菌发酵的乳制品（FMPP）摄入（为期4星期）可影响控制情感和感觉中枢处理的脑区活性。论文发表于《胃肠病学》（Gastroenterology. 2013；144：1394-1401）。

　　此项研究将无消化道或精神症状的健康女性随机给予为期4周的FMPP（12例）、非发酵乳制品（11例，对照）摄入或无干预（13例），FMPP含有的益生菌包括口服双歧杆菌、嗜热链球菌、保加利亚乳酸杆菌和乳酸乳球菌亚种。受试者在干预前后接受功能MRI检查，以测定情绪面孔注意力的脑反应性和静息脑活动。

　　结果显示，FMPP摄入与分布式功能网络任务相关性反应降低具有相关性（P =0 .004）；上述功能网络包括情感、内脏感觉和躯体感觉皮质。静息大脑的内在活性改变提示，FMPP摄入与中脑连接性改变相关；其可解释所观察到的任务期活性差异。

Consumption of Fermented Milk Product With Probiotic Modulates Brain Activity

Background & Aims

Changes in gut microbiota have been reported to alter signaling mechanisms, emotional behavior, and visceral nociceptive reflexes in rodents. However, alteration of the intestinal microbiota with antibiotics or probiotics has not been shown to produce these changes in humans. We investigated whether consumption of a fermented milk product with probiotic (FMPP) for 4 weeks by healthy women altered brain intrinsic connectivity or responses to emotional attention tasks.

Methods

Healthy women with no gastrointestinal or psychiatric symptoms were randomly assigned to groups given FMPP (n = 12), a nonfermented milk product (n = 11, controls), or no intervention (n = 13) twice daily for 4 weeks. The FMPP contained Bifidobacterium animalis subsp Lactis, Streptococcus thermophiles, Lactobacillus bulgaricus, and Lactococcus lactis subsp Lactis. Participants underwent functional magnetic resonance imaging before and after the intervention to measure brain response to an emotional faces attention task and resting brain activity. Multivariate and region of interest analyses were performed.

Results

FMPP intake was associated with reduced task-related response of a distributed functional network (49% cross-block covariance; P = .004) containing affective, viscerosensory, and somatosensory cortices. Alterations in intrinsic activity of resting brain indicated that ingestion of FMPP was associated with changes in midbrain connectivity, which could explain the observed differences in activity during the task.

Conclusions

Four-week intake of an FMPP by healthy women affected activity of brain regions that control central processing of emotion and sensation.