52, 199-210 (July/August 2001)
A double-blind evaluation of the activity of
an anti-cellulite product containing retinol, caffeine, and
ruscogenine by a combination of several non-invasive methods
CHRISTIANE BERTIN, HELENE ZUNINO, JEAN-CHRISTOPHE PITTET,
PATRICK BEAU, PASCAL PINEAU, MARC MASSONNEAU, CAROLINE ROBERT,
and JOHN HOPKINS, Johnson & Johnson Consumer France, 1 rue Camille
Desmoulins, 92787 Issy les Moulineaux (C.B., H.Z., C.R., J.H.),
Spincontrol, 7 rue Dabilly, 37000 Tours (J.-C.P., P.B.), and
IoˆDP, 36 rue du Chemin Vert, 75011 Paris (P.P., M.M.), France.
Accepted for publication April 15, 2001.
Synopsis
A double-blind, randomized, placebo-controlled study was
conducted with 46 healthy female volunteers in order to test
an anti-cellulite product containing retinol, caffeine and ruscogenine.
An evaluation of different parameters related to cellulite appearance,
i.e., the skin macrorelief, the dermal and hypodermal structures,
the skin mechanical characteristics, and the cutaneous flowmetry
was assessed using several non-invasive methods. This combination
of different evaluation methods resulted in the demonstration
of significant activity of the anti-cellulite product versus
baseline and showed its superiority versus the placebo in skin
macrorelief (decrease of the "orange peel" effect) and an increase
in cutaneous microcirculation. By using a combination of methods,
it was possible to detail the activity of an anti-cellulite
product and to show superiority of the product in comparison
with the placebo.
52, 211-224 (July/August 2001)
Differential scanning calorimetry studies of
sebum models
MONICA R. MOTWANI, LINDA D. RHEIN, and JOEL L. ZATZ, Rutgers-The
State University of New Jersey, College of Pharmacy, 160 Frelinghuysen
Road, Piscataway, NJ 08854 (M.R.M., J.L.Z.), and SmithKline
Beecham Consumer Healthcare, 1500 Littleton Road, Parsippany,
NJ 07054 (L.D.R.). Accepted for publication April 15, 2001.
Synopsis
Human sebum is a mixture of triglycerides, fatty acids,
wax esters, squalene, cholesterol, and cholesterol esters. P.
acnes, a bacterium that is normally found on the skin, hydrolyzes
certain triglycerides to fatty acids, thereby changing the sebum
composition. The objective of this study was to examine the
physical state of a model sebum and the effect of variations
in its composition on its physical properties including (a)
the carbon chain length of the components, (b) the ratio of
unsaturated to saturated components, and (c) the ratio of triglycerides
to fatty acids. A model sebum mixture was prepared based on
a composition reported in the literature and evaluated by differential
scanning calorimetry (DSC). Since cholesterol and cholesterol
esters contribute insignificantly to sebum composition, they
were not included. Squalene was kept constant (13%), while the
concentration of the rest of the components was varied. Variations
of sebum were prepared by dissolving all components in a 3:1
chloroform-methanol mixture for uniformity. Subsequently the
solvent was evaporated at room temperature. The samples were
then analyzed using DSC. Four distinct endotherms (namely, Mp-1,
Mp-2, Mp-3, and Mp-4) were observed between -50°C and 100°C.
Mp-1 and Mp-2 occurred below 0°C and were contributed by unsaturated
components. Mp-3 and Mp-4, which represent the saturated components,
occurred above 30°C. Thus, at normal skin temperature (skin
surface temperature is 32°C), sebum contains both a solid and
a liquid phase. All the transition temperatures increased with
an increase in carbon chain length for the same ratio of unsaturation
to saturation. A replacement of unsaturated components with
corresponding saturated components led to a decrease in the
transition temperatures for the former (Mp-1 and Mp-2) and an
increase in the transition temperatures for the latter (Mp-3
and Mp-4). Replacement of triglycerides with corresponding fatty
acids (mimicking the action of anaerobic bacteria) caused an
increase in Mp-2 and a decrease in Mp-4. In all cases, the final
melting temperature (Mp-4) was greater than the temperature
of the human skin surface (32°C); thus components contributing
to these endotherms are still solids at skin temperature. All
variations in the sebum model led to mixtures of solids and
liquids at skin temperature. Considering a reduction in Mp-3
and/or Mp-4 to represent sebum "fluidization," it was achieved
by a decrease in carbon chain length, an increase in unsaturation,
or a substitution of triglycerides by corresponding fatty acids.
Preferential enrichment with the saturated species will lead
to enrichment of solids versus liquids in the sebum, presumably
making it difficult for the liquid phase to dissolve the solids.
It seems plausible that perturbation of the balance of solid
and liquid components of sebum, such as by P. acnes action,
may lead to blockage of the follicle. Future research will investigate
strategies to dissolve and/or liquify the solid phase of sebum.
52, 225-236 (July/August 2001)
Effect of formulation on the delivery and metabolism
of a-tocopheryl acetate
MEERA RANGARAJAN and JOEL L. ZATZ, Schering Plough Research
Institute, Kenilworth, NJ 07033-0530 (M.R.), and Rutgers-The
State University of New Jersey, Department of Pharmaceutics,
College of Pharmacy, 160 Frelinghuysen Road, Piscataway, NJ
08854-8020 (J.R.Z.). Accepted for publication April 15, 2001.
Data contained in this paper were presented at the Annual Scientific
Seminar of the Society of Cosmetic Chemists, Toronto, Ontario,
May 11-12, 2000.
Synopsis
The effect of delivery system on the permeation and metabolism
of a-tocopheryl acetate (a-TAc) was studied in micro-Yucatan
pig skin, which closely resembles human skin. Various a-tocopheryl
acetate formulations, including a simple isopropyl myristate
(IPM) solution, an o/w emulsion, microemulsions, which differed
in their oily phase content, and alcoholic and hydroalcoholic
gels were made. A suitable HPLC method was developed and validated
to separate and quantify a-TAc and a-tocopherol (a-T). Dulbecco's
modified phosphate-buffered saline with 3% bovine serum albumin
(DMPBS-BSA 3%) served as the receptor media to ensure tissue
viability and to maintain skin conditions. Finite doses (5 µl)
of the formulations were applied to viable pig skin using a
statistically approved randomized complete block design. Data
were analyzed using Tukey's studentized range test, and interday
variability was estimated using an F-test. About 70% of the
active was recovered from the wash, representing the amount
adhering to the surface of the skin. a-TAc underwent metabolism
in pig skin to the active antioxidant, a-T. The identity of
the HPLC peaks were confirmed by spiking studies using known
standards. The extent of metabolism was found to be formulation-dependent.
No a-T was, however, detected in the stratum corneum. A higher
extent of metabolism was obtained for the IPM solution, a microemulsion
containing IPM as the oily phase, and the hydroalcoholic gel,
when calculated based on the percent of total a-TAc permeated
in the viable skin. Metabolism occurred in pig skin to the extent
of 15-20% in terms of the total amount of a-TAc permeated in
the viable skin and stratum corneum. Thus the topical delivery
and metabolism of a-TAc were found to be dependent on formulation.
52, 237-250 (July/August 2001)
Development of a device to measure human hair
luster
YUTAKA TANGO and KOICHI SHIMMOTO, KOSE´ Corporation, Research
& Development Division, Fundamental Research Laboratory, 1-18-4
Azusawa, Itabashi-ku, Tokyo 174-0051, Japan. Accepted for publication
April 15, 2001.
Synopsis
Evaluating human hair luster is important in developing
effective hair care products. Many methods of measuring human
hair luster have been proposed, but most have major disadvantages:
some require cutting the subject's hair, some utilize bulky
equipment, and some take much time. A device that does not impose
excessive burden on the subject and hair, but can easily and
conveniently measure human hair luster, has not yet been developed.
Overcoming the disadvantages of the traditional method, our
new device can measure luster accurately without cutting the
hair. Neither the subject's hairstyle nor its color influences
the measurements. The device is small, and the time required
for measurement is only 0.2 sec. The hair of 84 subjects was
evaluated using this device, and there was a high correlation
between the sensory score and the measurements obtained.
52, 251-253 (July/August 2001)
Abstracts Journal of the Society of Cosmetic Chemists
Japan Vol. 34, No. 3, 2000*
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