Five human ceramidase genes have been identified, including ASAH1, ASAH2, ACER1, ACER2
, and ACER3, and their protein products are classified as the acid (ASAH1), neutral (ASAH2), and alkaline ceramidase (ACER1-3) subtypes according to their pH optimum for their catalytic activity .
Four differentially expressed genes were selected to validate by RT-qPCR, including Acer2, Slc38a2, Ppp1r3c, and Pgam1.
The results of RNA-seq showed that, compared with the WT group, the expressions of Acer2, Slc38a2, Ppp1r3c, and Pgam1 were depressed in LV tissue of the DB group mice.
Alkaline ceramidase 2 (Acer2) is a type of ceramidases, which are key enzymes of the degradation of intracellular ceramide and hydrolyzed ceramide to sphingosine and then further phosphorylated to sphingosine-1-phosphate (S1P) by sphingosine kinase .
The results of this study showed that compared with the mice of the WT group, the mRNA content of Pgam1 and Acer2 in myocardium of the DB group mice decreased significantly.
It is concluded that the effect on improving diastolic function of the left ventricle and promoting the mRNA expression of Pgam1 and Acer2 of Gegen Qinlian decoction may be attributed to berberine, baicalin, liquiritigenin, and liquiritin.
The mRNA expressions of (a) Slc38a2, (b) Ppp1r3c, (c) Acer2, and (d) Pgam1 in each group (n = 4 - 5).
The expression of the following enzymes was investigated: ceramide synthase 2 (CerS2), ceramide synthase 4 (CerS4), fatty acid elongase 1 (ELOVL1), fatty acid elongase 3 (ELOVL3), alkaline ceramidase 2 (ACER2), serine palmitoyltransferase, long chain base subunit 2 (SPTLC2), sphingomyelin phosphodiesterase 1 acid lysosomal (SMPD1), and stearoyl-CoA desaturase (delta-9-desaturase, SCD1).
SCD1 and ACER2 were not significantly changed in the ST groups.