Overfeeding and overweight rapidly reprogram inflammatory signaling

Area of Science:

• Metabolic and Inflammatory Signaling
• Microbiome Research
• Nutritional Science

Background:

• Overweight and obesity are linked to increased mortality risk.
• Early inflammatory changes from obesogenic diets are not well understood.
• Existing research often uses long-term high-fat diet models.

Purpose of the Study:

• To investigate inflammatory signaling changes after short-term overfeeding.
• To characterize a mouse model of overweight induced by a 7-day Western diet.
• To compare short-term and long-term Western diet effects.

Main Methods:

• Developed a mouse model using a 7-day Western diet (high saturated fat, sucrose).
• Compared with standard low-fat diet and a 22-week Western diet.
• Analyzed weight gain, metabolic markers, liver health, microbiome diversity, and immune cell signaling.

Main Results:

• Short-term Western diet caused 6% weight gain; long-term caused 92% weight gain.
• Both diets increased cholesterol, triglycerides, insulin, and leptin.
• Short-term diet induced comparable inflammation (TLR4 expression, cytokine levels) to the long-term diet.

Conclusions:

• One week of a Western diet is sufficient to induce inflammation characteristic of chronic obesity.
• Early dietary interventions are crucial for managing inflammatory disorders.
• Diet significantly impacts preclinical models and clinical health outcomes.