Introduction
Acute pancreatitis (AP) is an acute inflammatory autodigestive disorder triggered by dysfunction of pancreatic exocrine activity and represents the most common gastrointestinal emergency in clinical practice. Global data indicate an annual incidence rate of 33.74 per 100,000 population and a mortality rate of 1.16 per 100,000. Despite ongoing optimization of therapeutic strategies, current clinical management primarily relies on supportive care and surgery. Hypertriglyceridemia (HTG) is the second leading etiological factor for AP, accounting for 10.36% of cases. Compared to other causes, HTG-associated acute pancreatitis (HTG-AP) exhibits higher recurrence rates and more severe complications (e.g., pancreatic necrosis and renal insufficiency). With the rising prevalence of HTG, the disease burden of HTG-AP is increasing, yet its specific pathogenic mechanisms remain unclear.
Aims & Methods
This study integrated whole-genome sequencing (WGS) and next-generation sequencing (NGS) to screen for shared mutations in the exonic regions of 5 HTG-AP family members. Candidate genes were identified based on MutationTaster classification and CADD scores. A mouse model carrying the PDLIM2 gene rs145349678 mutation was constructed using CRISPR/Cas9 technology, and an HTG-AP animal model was established. Pancreatic and hepatic histopathology (HE staining) and serological markers (TG, lipase, amylase, IL-6) were analyzed to evaluate the impact of the mutation on pancreatitis severity and hepatic lipid deposition.
Results
A clinical HTG-AP family was identified, with all 5 members exhibiting hypertriglyceridemia, including 2 cases of recurrent pancreatitis. WGS revealed 278 mutation sites across 10 chromosomes (involving 23 genes) in the family, and NGS validation narrowed these to 7 candidate loci. The PDLIM2 rs145349678 mutation (NM_001368120.1:exon9:c.C1055T:p.A352V), located within the LIM domain (which mediates protein localization and signaling transduction), was selected as the target due to cross-species conservation. Experimental results demonstrated that HTG-AP mice with the PDLIM2 mutation exhibited significantly aggravated pancreatic pathological damage (edema, hemorrhage, and inflammatory cell infiltration; *P* < 0.05), elevated serological markers (TG: 2.3 ± 0.4 vs. 1.5 ± 0.3 mmol/L; lipase: 520 ± 68 vs. 320 ± 45 U/L; IL-6: 48.2 ± 6.1 vs. 28.5 ± 4.3 pg/mL; *P* < 0.01 for all), and a 2.3-fold increase in hepatic lipid deposition (*P* < 0.001) compared to controls.
Conclusion
The PDLIM2 rs145349678 mutation exacerbates inflammatory responses and hepatic lipid accumulation in HTG-AP by modulating lipid metabolism. This finding provides new insights into the pathogenesis of HTG-AP and potential therapeutic targets.