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Updated: Dec 9, 2025
Author Spotlight: Investigating the Potential of Chinese Herbal Medicinal Active Dioscin in Treating IgA Nephropathy
Published on: October 13, 2023
Intravenous administration of Streptococcus mutans induces IgA nephropathy-like lesions
Shuhei Naka1, Kaoruko Wato2, Taro Misaki3,4
1Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Okayama, Japan.
Background:
IgA nephropathy (IgAN) is one of the most frequently occurring types of chronic glomerulonephritis. Previous analyses have revealed that a major pathogen of dental caries, Streptococcus mutans [which expresses collagen-binding protein (Cnm) on its surface], is involved in the pathogenesis of IgAN.
Methods:
Cnm-positive S. mutans isolated from a patient with IgAN was intravenously administered to specific pathogen-free Sprague-Dawley rats to evaluate their kidney conditions.
Results:
The urinary protein level of the S. mutans group reached a plateau at 30 days, with increased numbers of mesangial cells and an increased mesangial matrix. The numbers of rats with IgA-positive and/or C3-positive glomeruli were significantly greater in the S. mutans group than in the control group at 45 days (P < 0.05). Electron microscopy analyses revealed electron-dense depositions in the mesangial area among rats in the S. mutans group. There were significantly more CD68-positive cells (macrophages) in the glomeruli of the S. mutans group than in the glomeruli of the control group during the late phase (P < 0.05), similar to the findings in patients with IgAN.
Conclusion:
Our results suggested that intravenous administration of Cnm-positive S. mutans caused transient induction of IgAN-like lesions in rats.
