Response-to-injury Hypothesis

1. Accumulation of lipoproteins

(Mainly LDL and its oxidized forms) in the vessel wall. Low-density lipoprotein molecules (LDL) becoming oxidized (Idl-ox) by free radicals, particularly oxygen free (ROS). When oxidized LDL comes in contact with an artery wall, a series of reactions occur to repair the damage to the artery wall caused by oxidized LDL. Cholesterol can move in the bloodstream of reactions occur to repair the only by being transported by lipoproteins.

2. Monocyte adhesion to the endothelium

Followed by migration into the intima and transformation into macrophages and foam cells. The body's immune system responds to the damage to the artery wall caused by oxidized LDL by sending specialized white blood cells (macrophages and T-lymphocytes) to absorb the oxidized-LDL forming specialized foam cells. Unfortunately, these white blood cells are not able to process the oxidized-LDL, and ultimately grow then rupture, depositing a greater amount of oxidized cholesterol into the artery wall. This triggers more white blood cells, continuing the cycle.

3. SMC proliferations and ECM production

Eventually, the artery becomes inflamed. The cholesterol plaque causes the smooth muscle cells to enlarge and form a hard cover over the affected area. This hard cover is what causes a narrowing of the artery, reduces the blood flow and increases blood pressure.


Atherosclerosis develops gradually, typically begins in early adolescence, and is usually found in most major arteries. There are usually no atherosclerosis symptoms until an artery is so narrowed or clogged that it can't supply adequate blood to your organs and tissues. Sometimes a blood clot completely obstructs blood flow, or even breaks apart and causes blood clots that can trigger a heart attack or stroke.

Atherosclerosis symptoms depend on which arteries are affected. For example:

  • Atherosclerosis in heart arteries, have symptoms similar to those of a heart attack, such as chest pain (angina).
  • Atherosclerosis in the arteries leading to brain, have symptoms such as sudden numbness or weakness in your arms or legs, difficulty speaking or slurred speech, or drooping muscles in your face.
  • Atherosclerosis in the arteries in arms and legs, produces decreased blood flow is called peripheral artery occlusive disease (PAOD).have symptoms such as leg pain when walking.
  • Sometimes atherosclerosis causes erectile dysfunction in men.


The complications of atherosclerosis depend on the location of the blocked arteries. For example:

  • Coronary artery disease. When atherosclerosis narrows the arteries close to your heart, you may develop coronary artery disease, which can cause chest pain (angina) or a heart attack.
  • Carotid artery disease. When atherosclerosis narrows the arteries close to your brain, you may develop carotid artery disease, which can cause a transient ischemic attack (TIA) or stroke.

Lifestyle and home remedies

Lifestyle changes can help prevent or slow the progression of atherosclerosis.

  • Stop smoking.
  • Exercise most days of the week.
  • Eat healthy foods.
  • Manage stress.
  • Manage the condition of high cholesterol, high blood pressure, diabetes or other chronic disease.