Oral Cnm-positive Streptococcus Mutans Expressing Collagen Binding Activity is a Risk Factor for Cerebral Microbleeds and Cognitive Impairment

• Published in: Scientific reports Vol. 6; no. 1; p. 38561
• Main Authors: Watanabe, Isao, Kuriyama, Nagato, Miyatani, Fumitaro, Nomura, Ryota, Naka, Shuhei, Nakano, Kazuhiko, Ihara, Masafumi, Iwai, Komei, Matsui, Daisuke, Ozaki, Etsuko, Koyama, Teruhide, Nishigaki, Masaru, Yamamoto, Toshiro, Tamura, Aiko, Mizuno, Toshiki, Akazawa, Kentaro, Takada, Akihiro, Takeda, Kazuo, Yamada, Kei, Nakagawa, Masanori, Tanaka, Tokutaro, Kanamura, Narisato, Friedland, Robert P., Watanabe, Yoshiyuki
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09.12.2016; Nature Publishing Group
• Subjects: 692/499; 692/617; Cognitive ability; Collagen; Dementia; Dementia disorders; Humanities and Social Sciences; multidisciplinary; Polymerase chain reaction; Risk factors; Saliva; Science; Streptococcus; Streptococcus infections; Stroke
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep38561

Cerebral microbleeds (CMBs) are an important risk factor for stroke and dementia. We have shown that the collagen binding surface Cnm protein expressed on cnm -positive Streptococcus mutans is involved in the development of CMBs. However, whether the collagen binding activity of cnm -positive S. mutans is related to the nature of the CMBs or to cognitive impairment is unclear. Two-hundred seventy nine community residents (70.0 years) were examined for the presence or absence of cnm -positive S. mutans in the saliva by PCR and collagen binding activity, CMBs, and cognitive function were evaluated. Cnm-positive S. mutans was detected more often among subjects with CMBs (p < 0.01) than those without. The risk of CMBs was significantly higher (odds ratio = 14.3) in the group with S. mutans expressing collagen binding activity, as compared to the group without that finding. Deep CMBs were more frequent (67%) and cognitive function was lower among subjects with cnm -positive S. mutans expressing collagen binding activity. This work supports the role of oral health in stroke and dementia and proposes a molecular mechanism for the interaction.