The tomato saponin, esculeoside A.

Area of Science:

• Natural Product Chemistry
• Pharmacology
• Nutritional Science

Background:

• Esculeoside A (2) is a spirosolane steroidal glycoside found in tomatoes (Solanum lycopersicum).
• Its content varies across tomato types and processing stages.
• Tomatine (1) is a precursor to esculeoside A (2) in ripe tomatoes.

Purpose of the Study:

• To investigate the content variability of esculeoside A (2) in different tomato varieties and products.
• To explore the metabolic fate of esculeoside A (2) and its derivatives in humans and animal models.
• To evaluate the potential cardiovascular effects of esculeoside A (2) and its aglycone, esculeogenin A (3).

Main Methods:

• Analysis of esculeoside A (2) content in various tomato samples.
• Metabolic studies involving human volunteers consuming tomatoes.
• In vitro studies on macrophage cholesterol ester accumulation.
• In vivo studies using apoE-deficient mice to assess lipid profiles and atherosclerosis.

Main Results:

• Esculeoside A (2) is formed from tomatine (1) during tomato ripening and converted to other glycosides in overripe fruit.
• Human consumption of tomatoes led to the excretion of androstane derivatives.
• Esculeogenin A (3) inhibited cholesterol ester accumulation in macrophages by affecting ACAT.
• Oral esculeoside A (2) administration in mice reduced serum cholesterol, triglycerides, and LDL-cholesterol, and lessened atherosclerotic lesions.

Conclusions:

• Esculeoside A (2) and its derivatives exhibit significant cholesterol-lowering and anti-atherosclerotic properties.
• Tomato consumption influences human lipid metabolism.
• Esculeoside A (2) demonstrates potential as a therapeutic agent for cardiovascular disease prevention.