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Oral Cnm-positive Streptococcus Mutans Expressing Collagen Binding Activity is a Risk Factor for Cerebral Microbleeds
Isao Watanabe1,2, Nagato Kuriyama1,3, Fumitaro Miyatani1,2
1Department of Epidemiology for Community health and Medicine, Kyoto Prefectural University of Medicine, Kyoto, 6028566, Japan.
Abstract:
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.
Insights
Oral bacteria Streptococcus mutans expressing collagen-binding protein Cnm are linked to cerebral microbleeds (CMBs), a stroke and dementia risk. This suggests a molecular mechanism connecting oral health to neurological conditions.
Area of Science:
- Neurology
- Microbiology
- Oral Health
Background:
- Cerebral microbleeds (CMBs) are significant risk factors for stroke and dementia.
- The collagen-binding surface protein Cnm from Streptococcus mutans (S. mutans) has been implicated in CMB development.
- The specific relationship between collagen-binding activity of S. mutans, CMB characteristics, and cognitive decline remains unclear.
Purpose of the Study:
- To investigate the association between collagen-binding activity of cnm-positive S. mutans and the presence and nature of CMBs.
- To determine if cnm-positive S. mutans expressing collagen-binding activity correlates with cognitive impairment.
Main Methods:
- Polymerase chain reaction (PCR) was used to detect cnm-positive S. mutans in saliva samples from 279 community residents.
- Collagen-binding activity, CMBs (including location), and cognitive function were evaluated in participants.
- Statistical analyses were performed to assess correlations and risks.
Main Results:
- Cnm-positive S. mutans was detected more frequently in individuals with CMBs (p < 0.01).
- The presence of S. mutans expressing collagen-binding activity significantly increased the risk of CMBs (odds ratio = 14.3).
- Deep CMBs were more prevalent (67%), and cognitive function was reduced in subjects with cnm-positive S. mutans expressing collagen-binding activity.
Conclusions:
- This study supports a role for oral health, specifically S. mutans with collagen-binding activity, in the pathogenesis of CMBs.
- A molecular mechanism linking oral bacteria to stroke and dementia risk is proposed.
- Findings highlight the importance of oral hygiene in maintaining neurological health and preventing cognitive decline.
