• Natural Product Sciences
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• v.18 no.2
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• pp.116-120
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• 2012

Pancreatic lipase digests dietary fats by hydrolysis, which is a key enzyme for lipid absorption. Therefore, reduction of fat absorption by the inhibition of pancreatic lipase is suggested to be a therapeutic strategy for obesity. We previously reported coumarins and secoiridoids of Fraxinus rhynchophylla as inhibitory constituents on adipocyte differentiation. Further investigation on F. rhynchophylla led to the isolation of lignan derivatives such as lignans (1 - 10), sesquilignans (11 - 14) and coumarinolignans (15 - 17). Among them, coumarinolignans and sesquilignans were first reported from Fraxinus species. Among the constituents isolated, sesquilignans showed the significant inhibition on pancreatic lipase, whereas lignans and coumarinolignans exerted weak effects.

• Biomolecules & Therapeutics
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• v.20 no.6
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• pp.526-531
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• 2012

During our on-going studies to identify bioactive compounds in medicinal herbs, we found that saucerneol F (SF), a naturally occurring sesquilignan isolated from Saururus chinensis (S. chinensis), showed in vitro anti-inflammatory activity. In this study, we examined the effects of SF on the generation of 5-lipoxygenase (5-LO) dependent leukotriene $C_4$ ($LTC_4$), cyclooxygenase-2 (COX-2) dependent prostaglandin $D_2$ ($PGD_2$), and on phospholipase $C{\gamma}1$ ($PLC{\gamma}1$)-mediated degranulation in SCF-induced mouse bone marrow-derived mast cells (BMMCs). SF inhibited eicosanoid ($PGD_2$ and $LTC_4$) generation and degranulation dose-dependently. To identify the molecular mechanisms underlying the inhibition of eicosanoid generation and degranulation by SF, we examined the effects of SF on the phosphorylation of $PLC{\gamma}1$, intracellular $Ca^{2+}$ influx, the translocation of cytosolic phospholipase $A_2$ ($cPLA_2$) and 5-LO, and on the phosphorylation of MAP kinases (MAPKs). SF was found to reduce intracellular $Ca^{2+}$ influx by inhibiting $PLC{\gamma}1$ phosphorylation and suppressing the nuclear translocations of $cPLA_2$ and 5-LO via the phosphorylations of MAPKs, including extracellular signal-regulated protein kinase-1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38. Taken together, these results suggest that SF may be useful for regulating mast cell-mediated inflammatory responses by inhibiting degranulation and eicosanoid generation.