Coumarins from the Stem Barks of Fraxinus rhynchophylla Inhibit Adipocyte Differentiation. A Novel Candidate for Weight Loss Supplement?

A recent study by Shin et al. (Shin. 2010) identified another potential weight loss drug: The Coumarins from the stem barks of Fraxinus rhynchophylla inhibited adipocyte differentiation and thus the basic mechanism of irreversible fat gain.

Figure 1: Effects of Coumarins from F. rhynchophylla on Adipocyte Differentiation
in 3T3-L1 Cells on days 1-6 (Shin. 2010)

As figure 1 shows, Esculetin a Coumarin from Fraxinus rhynchophylla is highly effective in inhibiting early adipocyte differentiation (day 1). With regard to the underlying mechanism of action, the scientists speculate:

Esculetin (1) significantly blocked induction of PPARg expression in differentiated adipocytes, as measured by Western blot analysis (Fig. 4). In addition, esculetin (1) significantly inhibited adipocyte differentiation induced by troglitazone, a PPARg agonist (Fig. 5). These results suggest that esculetin (1) inhibited adipogenic differentiation, in part, via inhibition of PPARg -dependent pathway.

If the results can be reproduced in vivo, supplementing with Fraxinus rhynchophylla bark may prove a preventive measure against adiposity. If, however, you are already fat and dieting, inhibition of adipocyte differentiation won't be your major concern, anyway.