Geniposide, a potential therapeutical candidate for acute pancreatitis, inhibited trypsinogen-activated CBS degradation and remodeled transsulfuration metabolic flux

Acute pancreatitis (AP) is a potentially fatal condition with no targeted treatment options currently available. The premature activation of trypsinogen within acinar cells constitutes one of the pivotal early pathological events in AP, contributing to oxidative stress and inflammation. Disruption of the transsulfuration pathway also plays an important role in the development of AP. However, the interplay between these factors remains unclear. Here, we found that geniposide (GE), isolated from Gardenia jasminoides J. Ellis, ameliorated pancreatic acinar cell injury while exhibiting profound antioxidant activity both in vitro and in vivo. Then, we observed disrupted cysteine and methionine metabolism, manifested as reduced metabolic flux for cysteine and glutathione synthesis as well as increased toxic hydrogen sulfide in injured pancreatic acinar cells, all of which could be restored by GE treatment. Moreover, we revealed that cystathionine β-synthase (CBS), the rate-limiting enzyme of the transsulfuration pathway, undergoes cleavage by trypsin in injured pancreatic acinar cells and is responsible for the aforementioned metabolic reprogramming. Notably, GE stabilized the full-length CBS from cleavage primarily by suppressing trypsinogen activation and reducing the post-translational modification of truncated CBS forms, rather than through the direct, weak, and allosteric interactions. Our study is the first to highlight that early trypsin activation influences the proteolysis of metabolic enzymes, thereby affecting metabolic reprogramming and exacerbating the severity of AP. Additionally, we provide GE as a natural product candidate for preventing disease progression.