208 JOURNAL OF COSMETIC SCIENCE Though the initial viscosity of the cream containing polymer 2 (6400 centipoises) was greater than that of the marketed preparation (6000 centipoises), the overall release pattern of the drug from the cream containing polymer 2 was similar. However, there are similar findings in earlier published literature (15), which has indicated that a gel formulation (containing Carbopol 940 or emulsion base) with higher viscosity showed a better release profile than one with lower viscosity. CONCLUSION On the basis of the release parameters and storage stability, it seems that the cream prepared by using polymer 2 shows a good release pattern and storage stability and that it can be used successfully as hydrophilic cream base. REFERENCES (1) P. Balakrishnan, S.S. Sangole and B. B. Gogte, Pa/nt/nd/a, 44, 37 (1994). (2) B. N. Mundhe, S. P. Morey, and B. B. Gogte, Paint/ndi•, 44, 77 (1993). (3) G. Melin, Antiwrinkle beauty cream composition, Fr. Demande FR 2,693,371, Chem. Abs., 120, (1994). (4) D. S. Sheorey and A. K. Dorle, J. Microencapsulation, 11, 11 (1994). (5) Y. V. Pathak, R. L. Nikore, and A. K. Dorle, Int. J. Pharm. 24, 351 (1985). (6) Y. V. Pathak, and A. K. Dorle, IndianJ. Pharm. Sci., 48, 16 (1986). (7) P.Y. Klyuev, A.Y. Klyuev, I.V. Antonovich, A.K. Strakh, and O.A. Novikov, U.S.S.R. SU 1810368 A1, April 23, 1993. (8) S. Icli, F. Uysal, Turk. J. Chem., 16, 307-314 (1992). (9) C. W. Chien, J. Am. Chem. Soc., 62, 4762 (1960). (10) Y. V. Pathak, R. L. Nikore, and A. K. Dorle, Int. J. Pharm., 24, 351 (1985). (11) Nakagava et aL, U.S. Patent, 5,478,567, December 26, 1995. (12) Oda et al., U.S. Patent, 5,725,874, March 10, 1998. (13) N.H. Sahu, P.M. Mandaogade, A.M. Deshmukh, and A. K. Dorle, Biodegradation studies of rosin- glycerol ester derivative, J. Bioactive Compatible Polymers, 14, 344-360 (1999). (14) Y. W. Chien and P. R. Keshary, Drug. Dev. Ind. Pharm., 10, 883 (1984). (15) S. P. Patvardhan, K. S. Joshi, R. V. S. V. Vadlamudi, and S. G. Deshpande, Development and in vitro evaluation of diclofenac hydroxyethyl pyrrolidine formulations containing penetration enhancers, In- dianJ. Pharm. Sci., 61, 7-11 (1999).

j. Cosmet. sci., 53, 209-218 (July/August 2002) An in vitro, ex Lit, o, and in L, iL, O demonstration of the lipolytic effect of slimming liposomes' An unexpected ot-adrenergic antagonism L. THOLON, G. NELIAT, C. CHESNE, D. SABOUREAU, E. PERRIER, and J.-E. BRANKA, Co/etica, 32 rue Saint Jean de Dieu, 69007 Lyon (L.T., E.P., J.-E.B.), Cerep, Le Bois /'Ev•que, 86660 Celles L'Evescau/t (G.N., J.-E.B.), Biopredic, 14-18 rue Jean Pecker, 35000 Rennes (C.C.), and Decs, 1 rue du Golf Parc' Innolin, 33 700 Mdrignac (D.S.), France. Accepted for publication March 15, 2002. Synopsis Most of the slimming products already developed for cosmetic applications did not result from strategies that integrate whole lipolysis-regulating mechanisms. We thus focused our attention on a more complete integration of these mechanisms and we developed slimming liposomes (SLC) containing two micro- circulation activators, i.e., esculoside and Centella asiatica extracts, one phosphodiesterase inhibitor, i.e., caffeine, and one fatty acid-lB oxidation activator, i.e., L-carnitine. The validity of our approach was assessed through (a) in vitro tests demonstrating that SLC induced a dramatic increase in the cyclic adenosine monophosphate (cAMP) content in human adipocytes, with a subsequent rise in the nonesterified fatty acids (NEFA) content of human adipocyte incubation medium, and (b) in vivo studies showing that SLC could provide an actual potent slimming effect on human volunteers. Moreover, we give here, through binding experiments, the unambiguous demonstration that SLC is able to antagonize the %-adrenergic receptor that is known to reduce intracellular AMPc content and, subse- quently, to down-regulate lipolysis. This %-adrenergic antagonism has never been reported for any com- ponent of SLC, and this work is the first demonstration of the o•2-adrenergic antagonism of such a combination of active liposome compounds. INTRODUCTION In order to develop potent slimming products we have to (a) enhance the external skin grain (smoothness) and (b) produce a lipolytic effect on human adipocytes acting through main mechanisms regulating lipolysis. Address all correspondence to G. Neliat. 209