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Global Translational Medicine Angiotensinogen in liver steatosis

substrate adhesion (Figure A1[A]). DEGs in Cluster 2 overlapped DEGs highlighted six DEGs that were present
were related to sterol and secondary alcohol biosynthetic in the top five biological processes, all of which related
processes as well as fatty acid and steroid metabolic to cell division (Figure 4D). These six DEGs represented
processes (Figure A1[B]). DEGs in Cluster 3 were related potential target genes relating to the contribution of AGT
to catabolic processes (Figure A1[C]). Interestingly, in to diet-induced steatosis. Among these genes, Smpd3,
Cluster 4 which was consistent with the progression of liver Mki67, and Top2a demonstrated the highest normalized
steatosis, DEGs were related to inflammation and included read count expression (Figure 4E).
major cytokines and chemokines, such as Ccl2 and Cxcl1
(Figure 2C and D). 3.5. mRNA abundance of target cell division genes
increased concurrently with steatosis in hepAGT +/+
3.3. Hepatocyte-specific AGT deficiency increased mice
the hepatic transcriptome related to metabolic To verify that the abundance of potential target genes was
processes and suppressed cell division processes at increased during feeding of WD in hepAGT +/+ mice,
14 days of WD feeding normalized read count data for each DEG were analyzed
We next investigated the impact of hepAGT-/- on separately. Plk1 displayed a statistically significant increase
WD-induced transcriptomic alterations in liver. H&E in abundance only after 14 days of WD feeding compared
and Oil Red O staining revealed that WD-induced to baseline (0 days of WD). Increased abundances of
liver steatosis becomes discernible after 14 days of WD Smpd3, Dtl, Cdc6, Mki67, and Top2a were detected after 14
feeding (Figure 1B-D). Therefore, to determine molecular and 42 days of feeding WD, which was consistent with the
mechanisms by which hepatocyte-derived AGT contributes initiation and advanced phases of steatosis in hepAGT +/+
to disease initiation, additional bulk RNA sequencing mice (Figure 5).
was performed using livers from hepAGT -/- mice after 4. Discussion
14 days of WD feeding. DEG analyses were conducted by
comparing these newly generated data with the previously In the present study, we performed two bulk RNA
sequenced transcriptomes of hepAGT +/+ mice after sequencing analyses to explore the molecular basis
the same interval of 14 days of WD feeding (Figure 3A). underlying the inhibition of WD-induced liver steatosis
Agt mRNA deletion was verified by reduction of mRNA and protective effects of hepatocyte-specific AGT
reads aligned to exon 2 of Agt in hepAGT -/- mice deletion. We found that genes related to inflammatory
(Figure 3B). Despite the significant reduction, only 128 biological processes were increased consistently with
DEGs were detected between genotypes. Sixty-two DEGs the progression of steatosis. The mRNA abundance of
were upregulated and 66 DEGs were downregulated in several key inflammatory cytokines was maximal at an
hepAGT -/- mice compared to wild-type (Figure 3C). GO advanced stage of steatosis. Surprisingly, despite the
enrichment analysis revealed that genes upregulated in established protective effect against WD-induced steatosis,
hepAGT -/- mice were related to metabolic and biosynthetic hepatocyte-specific AGT deficiency altered a select portion
processes (Figure 3D). Meanwhile, downregulated genes of the liver transcriptome, particularly genes related to
were related to cell division processes (Figure 3E). metabolic and cell division processes, during the initiation
phase of steatosis. By integrating data from the two RNA
3.4. Cell division-related genes elevated by WD sequencing analyses, we identified five molecules related
feeding were suppressed in hepatocyte-specific to cell division: Smpd3, Dtl, Cdc6, Mki67, and Top2a, as
AGT-deficient mice at 14 days of WD key mediators in suppressing WD-induced steatosis in
To define key molecules mediating the attenuation of hepAGT -/- mice.
WD-induced liver steatosis in hepAGT -/- mice, the two In this study, liver steatosis was defined histologically
RNA sequencing data were integrated (Figure 4A). We by the presence of intrahepatocellular lipid droplet
sought to isolate genes that were both increased in association accumulation. Macrovesicular steatosis, a defining feature
with WD-feeding and altered in hepAGT -/- mice at the of metabolic dysfunction-associated fatty liver disease
initiation phase of steatosis. Since Cluster 4 contained (MAFLD), 29-33 was observed after 14 days of WD feeding,
DEGs that were increased in abundance consistent with but not after 5 days, suggesting that 14 days of feeding
continued WD-feeding, DEGs in Cluster 4 were compared represents the initiation phase of pathology. This finding
against all DEGs identified by comparing hepAGT +/+ and is consistent with a previous study reporting hepatic
-/- mice at 14 days of WD-feeding (Figure 4B). Twenty- triglyceride content increased in mice after 14 days
four DEGs were overlapped between the two sequencing of a high-fat diet. In the present study, progressive
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datasets (Figure 4C). GO enrichment analysis within the macrovesicular steatosis was noted after 42 days of WD

Volume 4 Issue 2 (2025) 76 doi: 10.36922/gtm.6027