Inflammation is more persistent in type 1 diabetic mice.

Area of Science:

• Immunology
• Microbiology
• Endocrinology

Background:

• The impact of diabetes on the host's immune response to bacterial pathogens remains incompletely understood.
• Previous research has yielded conflicting results regarding whether diabetes enhances or diminishes the inflammatory response.

Purpose of the Study:

• To investigate how diabetes mellitus influences the acute and sustained inflammatory response to bacterial inoculation.
• To determine if diabetes alters bacteria-host interactions by modulating chemokine and cytokine expression.

Main Methods:

• Streptozotocin-induced diabetes model in mice inoculated with P. gingivalis.
• Assessment of inflammatory infiltrate and mRNA expression of key chemokines (MIP-2, MCP-1) and TNF-alpha.
• Comparison between diabetic and normoglycemic control groups, including db/db type 2 diabetic mice.

Main Results:

• Diabetic mice showed significantly higher inflammatory infiltrate at day 3 post-inoculation compared to controls.
• Chemokine mRNA levels (MIP-2, MCP-1) remained elevated in diabetic mice by day 3, unlike in normoglycemic mice.
• Both streptozotocin-induced and db/db diabetic mice exhibited prolonged TNF-alpha expression.

Conclusions:

• Diabetes mellitus significantly alters the host's inflammatory response to bacterial challenge.
• The diabetic state is characterized by a prolonged and heightened inflammatory infiltrate and chemokine expression.
• These findings suggest that diabetes impairs the resolution of inflammation, potentially affecting bacteria-host interactions.