Surfactant protein D is proatherogenic in mice

Area of Science:

• Cardiovascular Biology
• Immunology
• Lipid Metabolism

Background:

• Surfactant protein D (SP-D) is an innate immune molecule involved in pathogen clearance and inflammation.
• SP-D influences lipid homeostasis, with pulmonary phospholipid accumulation noted in SP-D-deficient mice.
• Atherosclerosis involves inflammation and lipid deposition, suggesting a potential role for SP-D.

Purpose of the Study:

• To investigate the role of SP-D in the development of atherosclerosis.
• To determine if SP-D influences lipid metabolism and inflammatory processes relevant to atherogenesis.

Main Methods:

• Comparison of atherosclerotic lesion areas in SP-D-deficient (Spd-/-) mice and wild-type mice on an atherogenic diet.
• Analysis of plasma lipid profiles (HDL-C, total cholesterol, LDL-C) and TNF-alpha levels.
• Treatment of Spd-/- mice with a recombinant human SP-D fragment.

Main Results:

• Spd-/- mice exhibited significantly smaller atherosclerotic lesion areas (5.6-fold reduction) in aortic roots.
• Spd-/- mice showed elevated HDL cholesterol and reduced plasma TNF-alpha.
• Recombinant SP-D treatment decreased HDL-C, total cholesterol, and LDL-C in Spd-/- mice.

Conclusions:

• SP-D is proatherogenic in this mouse model.
• SP-D deficiency confers protection against atherosclerosis, likely due to improved lipid metabolism and altered inflammatory responses.
• SP-D's role in lipid homeostasis and inflammation impacts its contribution to atherosclerosis.