Differential expression of GLP1R, PCSK9, and SGLT2 in human aortic versus mitral valve tissues: exploratory findings in calcific aortic valve disease.

BACKGROUND

Calcific aortic valve disease (CAVD) is a common valvular heart disorder for which effective pharmacological treatments remain lacking. This study aimed to compare the expression and potential pathophysiological relevance of glucagon-like peptide-1 receptor (GLP1R), proprotein convertase subtilisin/kexin type 9 (PCSK9), and sodium-glucose cotransporter 2 (SGLT2) in human aortic valve (AV) and mitral valve (MV) tissues from patients undergoing valve replacement surgery.

METHODS

Surgically resected AV (n = 10) and MV (n = 13) tissue specimens were collected between March 2020 and December 2022. Target protein expression was assessed via immunohistochemistry (IHC), and valvular calcification was confirmed by Von Kossa staining. Subgroup analyses were performed within calcified vs. non-calcified AV tissues and within a bicuspid aortic valve (BAV) subset (n = 3 per group).

RESULTS

GLP1R, PCSK9, and SGLT2 expression levels were significantly elevated in AV tissues compared to MV tissues (all P < 0.001). Within calcified AV specimens, expression trends were higher than in non-calcified AV tissues, though these differences did not reach statistical difference (all P > 0.05). In the exploratory BAV subgroup (n = 3 per group), expression of all three targets was higher in calcified vs. non-calcified tissues (all P < 0.05).

CONCLUSION

These findings reflect differential expression between anatomically distinct valve types and do not establish CAVD-specific upregulation.