HMG coenzyme A reductase inhibitors work to __________ __________ and __________ __________ by blocking a key enzyme.

HMG coenzyme A reductase inhibitors, commonly known as statins, primarily focus on cholesterol management within the body. By inhibiting the enzyme HMG-CoA reductase, these drugs effectively lower low-density lipoproteins (LDL), which are often referred to as "bad cholesterol." A decrease in LDL levels reduces the risk of atherosclerosis and cardiovascular diseases, which is a primary therapeutic goal of statin therapy.

Additionally, while statins are not primarily aimed at raising high-density lipoproteins (HDL) or "good cholesterol," there is evidence to suggest that they can contribute somewhat positively to HDL levels as a secondary effect. However, the main action of these medications is undeniably the reduction of LDL, making this the correct choice for the question concerning the mechanism of HMG-CoA reductase inhibitors.

This understanding is crucial in pharmacology and patient care, as it establishes the foundational benefits of statin therapy in lipid management and cardiovascular risk reduction.