Apob, short for apolipoprotein B, is a crucial protein in the biosynthesis and metabolism of triglyceride-rich lipoproteins (TRLs), including very-low-density lipoprotein (VLDL) and chylomicron. These lipoproteins are closely related to atherosclerotic cardiovascular disease, highlighting the significance of Apob in cardiovascular health [1]. Zebrafish, with conserved lipid metabolism proteins and a human-like lipoprotein profile, serve as a valuable research model for studying Apob-containing lipoprotein metabolism. Any disruption in lipoprotein formation, often related to Apob, leads to visible phenotypes such as cytoplasmic lipid droplet accumulation and opaque yolk, enabling in-vivo exploration of the lipoprotein pathway [2].

Although no findings from KO/CKO mouse models are presented in the given references, studies have shown that Apob measurement may outperform low-density lipoprotein cholesterol level measurement in predicting atherosclerotic cardiovascular disease risk, yet its routine clinical adoption is hindered by lack of consistent guidance on interpretation and application [4]. In addition, Apob and CCL17 were identified as mediators in the protective effect of SGLT2 inhibition against myocardial infarction through proteome-wide mendelian randomization [3]. Also, plasma ApoB/AI ratio is a potential indicator for intracranial vulnerable atherosclerosis characterized by positive remodeling, especially in the posterior circulation [5].

In summary, Apob plays a vital role in lipoprotein metabolism and is associated with various cardiovascular and cerebrovascular conditions. Although direct evidence from KO/CKO mouse models is lacking in the provided references, research in zebrafish and human-based studies has revealed its significance in disease-related processes, which could potentially guide future research and clinical practice in these disease areas.