Publications

@article{Cha2024,

title = {Antipruritic effect of ursolic acid through MRGPRX2/MrgprB2-dependent inhibition of mast cell degranulation and reduced TSLP production},

author = {Jieun Cha and Juhee Ryu and Diwas Rawal and Wook-Joo Lee and Won-Sik Shim},

doi = {10.1016/j.ejphar.2024.176896},

issn = {0014-2999},

year  = {2024},

date = {2024-10-00},

urldate = {2024-10-00},

journal = {European Journal of Pharmacology},

volume = {981},

publisher = {Elsevier BV},

keywords = {Mast cell, MrgprB2, MRGPRX2, TSLP, Ursolic acid},

pubstate = {published},

tppubtype = {article}

}

@article{Adhikari2022,

title = {Caffeic acid phenethyl ester inhibits pseudo-allergic reactions via inhibition of MRGPRX2/MrgprB2-dependent mast cell degranulation},

author = {Nisha Adhikari and Won-Sik Shim},

doi = {10.1007/s12272-022-01405-2},

issn = {1976-3786},

year  = {2022},

date = {2022-09-00},

urldate = {2022-09-00},

journal = {Arch. Pharm. Res.},

volume = {45},

number = {9},

pages = {644--657},

publisher = {Springer Science and Business Media LLC},

abstract = {Mast cells play essential role in allergic reactions through the process called mast cell degranulation. Recent studies have found that a basic secretagogue compound 48/80 (C48/80) induces non-IgE-mediated mast cell degranulation via activation of human Mas-related G protein-coupled receptor X2 (MRGPRX2) and mouse MrgprB2. Although previous studies have revealed that caffeic acid (CA) and its derivatives possess anti-allergic effects via IgE-dependent manner, it is largely elusive whether these compounds have impact on MRGPRX2/MrgprB2 to exert inhibitory effects. Therefore, the present study investigated whether CA as well as its derivatives - rosmarinic acid (RA) and caffeic acid phenethyl ester (CAPE) - has the ability to inhibit the activity of MRGPRX2/MrgprB2 to evoke pseudo-allergic effects. As a result, it was found that CAPE inhibits C48/80-induced activation of MRGPRX2/MrgprB2, but neither CA nor RA showed discernible inhibition. Furthermore, the β-hexosaminidase release assay showed that CAPE inhibits mouse peritoneal mast cell degranulation in both IgE-dependent and MrgprB2-dependent manners. Additionally, mouse paw edema induced by C48/80 was dramatically suppressed by co-treatment of CAPE, suggesting that CAPE possesses a protective effect on C48/80-evoked pseudo-allergic reactions. The pretreatment of CAPE also significantly decreased scratching bouts of mice evoked by C48/80, demonstrating that CAPE also has an anti-pruritic effect. Therefore, these data implicate that CAPE can suppress pseudo-allergic reactions evoked by C48/80 via MrgprB2-dependent manner. Finally, molecular docking analysis showed that CAPE is predicted to bind to human MRGPRX2 in the region where C48/80 also binds, implying that CAPE can be a competitive inhibitor of MRGPRX2. In conclusion, it is found that CAPE has the ability to inhibit MRGPRX2/MrgprB2, leading to the prevention of mast cell degranulation and further to the alleviation of mast cell reactions. These results indicate that CAPE as a CA derivative could be developed as a new protective agent that exerts dual inhibition of mast cell degranulation mediated by IgE and MRGPRX2/MrgprB2.},

keywords = {Allergy, Calcium imaging, Mast cell, MrgprB2, MRGPRX2},

pubstate = {published},

tppubtype = {article}

}

@article{Song2022,

title = {Lithocholic Acid Activates Mas-Related G Protein-Coupled Receptors, Contributing to Itch in Mice},

author = {Myung-Hyun Song and Won-Sik Shim},

doi = {10.4062/biomolther.2021.059},

issn = {2005-4483},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {Biomol Ther (Seoul)},

volume = {30},

number = {1},

pages = {38--47},

publisher = {The Korean Society of Applied Pharmacology},

abstract = {The present study focused on lithocholic acid (LCA), a secondary bile acid that contributes to cholestatic pruritus. Although recent studies have found that LCA acts on MAS-related G protein-coupled receptor family member X4 (MRGPRX4) in humans, it is unclear which subtypes of MRGPRs are activated by LCA in mice since there is no precise ortholog of human MRGPRX4 in the mouse genome. Using calcium imaging, we found that LCA could activate mouse Mrgpra1 when transiently expressed in HEK293T cells. Moreover, LCA similarly activates mouse Mrgprb2. Importantly, LCA-induced responses showed dose-dependent effects through Mrgpra1 and Mrgprb2. Moreover, treatment with QWF (an antagonist of Mrgpra1 and Mrgprb2), YM254890 (Gαq inhibitor), and U73122 (an inhibitor of phospholipase C) significantly suppressed the LCA-induced responses, implying that the LCA-induced responses are indeed mediated by Mrgpra1 and Mrgprb2. Furthermore, LCA activated primary cultures of mouse sensory neurons and peritoneal mast cells, suggesting that Mrgpra1 and Mrgprb2 contribute to LCA-induced pruritus. However, acute injection of LCA did not induce noticeable differences in scratching behavior, implying that the pruritogenic role of LCA may be marginal in non-cholestatic conditions. In summary, the present study identified for the first time that LCA can activate Mrgpra1 and Mrgprb2. The current findings provide further insight into the similarities and differences between human and mouse MRGPR families, paving a way to understand the complex roles of these pruriceptors.},

keywords = {Bile acid, Calcium imaging, Itch, Lithocholic acid, MrgprA1, MrgprB2, MRGPRX4},

pubstate = {published},

tppubtype = {article}

}