日本研究人员日前报告说，一种变异链球菌会使脑出血的风险增高约3倍。这一发现将有助于开发预防和治疗脑出血的药物。
链球菌
日本大阪大学等机构的研究人员在新一期英国《自然—通讯》杂志上报告说，生活在口腔中的变异链球菌会导致蛀牙，60%至70%的日本人都携带这种细菌。研究人员还发现，约有8%的日本人携带一种含胶原蛋白的特殊变异链球菌。但在脑出血患者中，约有30%的人携带这种变异链球菌。由此推算，携带这种变异链球菌的人，其脑出血发病风险比其他人高出约3倍。
在动物实验中，研究人员用一种特殊设备破坏实验鼠的脑血管使其出血，并从人类脑出血患者唾液中采集这种变异链球菌投放到这些实验鼠的血管中。结果发现，投放变异链球菌的实验鼠的脑血管出血量比对照组实验鼠多五六倍。研究人员发现，这种变异链球菌的胶原蛋白会富集到血管破损处，妨碍血管修复，从而导致出血增加。
研究人员说，健康人携带此类变异链球菌并无太大问题，但对于高血压患者、吸烟者等血管较脆弱的人群，就容易引发脑出血。研究人员提醒这些“脆弱”人群更加注意养成健康生活习惯，警惕脑出血的发生。
相关英文论文摘要：
The collagen-binding protein of Streptococcus mutans is involved in haemorrhagic stroke
Although several risk factors for stroke have been identified, one-third remain unexplained. Here we show that infection with Streptococcus mutans expressing collagen-binding protein (CBP) is a potential risk factor for haemorrhagic stroke. Infection with serotype k S. mutans, but not a standard strain, aggravates cerebral haemorrhage in mice. Serotype k S. mutans accumulates in the damaged, but not the contralateral hemisphere, indicating an interaction of bacteria with injured blood vessels. The most important factor for high-virulence is expression of CBP, which is a common property of most serotype k strains. The detection frequency of CBP-expressing S. mutans in haemorrhagic stroke patients is significantly higher than in control subjects. Strains isolated from haemorrhagic stroke patients aggravate haemorrhage in a mouse model, indicating that they are haemorrhagic stroke-associated. Administration of recombinant CBP causes aggravation of haemorrhage. Our data suggest that CBP of S. mutans is directly involved in haemorrhagic stroke.
英文论文全文阅读：https://www.biodiscover.com/news/microbiology/library/1289.html
