ENVIRONMENT FRIENDLY GREEN CHEMICALS
Transcript
ENVIRONMENT FRIENDLY GREEN CHEMICALS
J. Appl. Cosmetol. 18, 51-63 (April-July 2000) ENVIRONMENT FRIENDLY GREEN CHEMICALS P. Morganti', G. Fabrizi', F.Guarneri' and C. Bruno• l .President/Director, R. & D - Mavì Sud S.r.l., Viale dell'Industria l, 04011 Aprilia (LT), ltaly Dept. of Internal Medicine, Aesthetic Medicine Training School , University of Rome "Tor Vergata", ltaly 2.Dermatological Dpt. Catholic University of Rome 3.R.&D l.S.C.D. 4 Physiology lnstitute, University of Urbino, ltaly Received: June, 1999, Presented at the Persona/ Care lngredients Asia C onference, Tahiland, 8-1 O March 2000. Key words: gelatin, glycine, PCA chitosan, polysaccharides, biomaterials, glycolic acid, skin roughness, skin dryness, skin hydrat ion. Summary Polysaccharides are the ma in source of green biomolecules used as biomaterials in phar macology and cosmeti c de rmato logy. The industriai interest about these molecules is continuously increasing and that's due to the different c haracteristics they proved to have: absence or near-absence of antigenicity, inability to cause a n inflammatory reaction and high ability to enhance stroma l-cell colonization and g lycoprotein sy nthesis when e mployed in ski n tissue repair and high environ men t compatibi lity. T he aim of this study was to evaluate the property of innovative and patented glico-chi tosa n a nd PCA chitosan ge ls to increase ski n hydration and e lasticity, and to evaluate its protective and anti- irritation pote ntia l efficacy. The two-month tria! was a randomi zed doubl e-bli nd-placebo-controlled study carried out on 60 dry ski nned female volunteers, aged 32-43 with a moderate xerosis of grade 5 accordi ng to Dahl. Surface li pids, skin hydrati on and TEWL were detected by the 3C System®(Dermotech, l taly). Sk in e lastic ity and softness were evaluated by the Dermaflex® A (Cortex Technology, De nmark). lrritation potential was detected by SOS Challenge test a nd Pyrexal Erythema test evaluati ng the intensity of ski n redness by Chromameter<» C 200. T he treatment by this green gels induced a significant and progressive improvement in skin hydrati on (fro m +30% to +80%, p<0 .005), skin surface li pids (fro m + I 0% to +60%, p<0 .005) and skin e lastic ity (+ 14%, p<0.005) and a contemporary decrease of TEWL (from -50% to - 70%, p<0.005) and free radicals (-25 %, p<0.005) compared to the baseline values. The most and unexpected property was the high anti- inflammatory acti vity recorded. The improvement, that starts to be evident fro m the first week of treatment, shows how these gels cou ld be conside red as usefu l means to improve skin hydration and elasticity of subjects affected by skin xerosis due to environmental or pathological reasons. No side effects were observed during the study period. Riassunto I polisaccaridi rappresentano la maggiore sorgente di molecole "verdi" utili come biomateri ali di 51 Envlfonment Friendfy Green Chem1cofs uso farmacologico e cosmetico. L'i nteresse industriale nei confronti di queste molecole è in continuo aumento date le loro particolari caratteristiche: assenza quasi totale nel provocare effetti antigenici, o processi infiammatori, capacità elevata di incrementare la colonizzazione delle cellule stromali e la sintesi delle glicoproteine, se utilizzate per la riparazione tissutale, ed alta compatibilità con l'ambiente . Scopo di questo studio è di valutare le proprietà innovative quali idratanti ed elasticizzanti cutanei ad attività antinfiammatoria di diversi gel chitosanici trattati con miscele di gelatina-glicina o PCA gelatina. E' stato condotto uno studio a doppio ceco su 60 pazienti volontari di sesso femminile di età tra i 32 ed i 43 a nni con cute particolarmente secca e disidratata di grado 5 secondo la classificazione Dahl. I lipidi di superficie, l'idratazione cutanea e la TEWL sono state controllate utilizzando il 3C System®(Dermotech, Italia) L'elasticità cutanea è stata controllata mediante l'utilizzazione del Dermaflex®A, mentre effetto antii rritante è stato determinato con la metodica dell'SDS e del Pirexal e controllato anche con l'utilizzazione del Chromameter®C200. Il trattamento con questi gel "verdi" ha indotto un incremento statisticamente significativo dell'idratazione cutanea (dal + 30 ali'+ 80%, p<0,005) dei lipidi di superficie (dal+ IO al + 60%, p<0,005), della elasticità cutanea (+ 14% p<0,005) ed una contemporanea diminuzione della TEWL (dal - 50 al - 70%,p<0,005) e dei radicali liberi (-25%, p<0,005) rispetto ai valori iniziali. Il risultato più sorprende nte ed inaspettato è stata l'attività antiinfiammatoria riscontrata dei prodotti controllati. I miglioramenti, evidenti fin dalla prima settimana di trattamento dimostrano come questi gel possano essere utilizzati per migliorare l'idratazione e l 'elasticità della cute di persone affette da xerosi cutanea provocata anche da cause patologiche in atto. Non sono stati osservati effetti secondari di alcun genere dopo il periodo di trattamento. 52 P.Morgont1. G Fobnz1. F.Guornen and e Bruno INTRODUCTION Polysaccha rides a re the main source of green bio-molecules for use as biomaterials in pharmacology and cosmeti c dermatology. ( 1-11 ) The industri ai interest about these molecules is co ntinuously increasing because of the interesting characteristics they proved to have: absence or near-absence of a ntigenicity, inability to cause an inflammatory reaction and high ability to enhance stromal-cell colonization and glycoprotein synthesis, when e mployed in skin tissue repair and hi gh environment compatibility. These cha racteristics have been highlighted partic ul arly in the naturally occurring chitosan and chitosan derivatives (4- 11 ). These green compounds because of the ir biocompatibility with the huma n body have been employed extensive ly in th e developme nt of a nioni c/cationic polysacc haride matrices for mi c roparticulate drug delivery ( 12- 15). They seem also to be immuno-potentiating, considering their simil ariti es with hyaluronic acid through the common N-ace tylglucosamine sugar, and showed to be mucoadhesive. As matter of fact, chitosans previde an attracti ve muco-adhesiveness because of their polycationic comple mentarity to the polyanionic mucins, whic h constitute the key macromolecular component of muc us ( 16, 17). Moreover their topica! application seems also to minimi ze scarring a nd improve skin healing process (1 8-22). The formul ation of this gel is based on the exclusive usage of a new chitosan derivati ve solubilized with g lycolic acid and/or with PCA (pyrrolidon carboxylic acid), and subsequently treated with a patented mixture of gelatin-glycine additi vated with sodium methyl hydroxylglycinate (30). The exclu sive use of raw materials of natural origin, allows to define "green" the gel obtained , also beca use completely and of pro ved eco-co mpatibility. In fact the presence of this preservati ve compound, as methylene glycol, in this c hitosan-based formulation does not provoke liberation of free formaldehyde at skin leve! because of the strong presence of groups NH2 of chitosan. Therefore from two moles of chitosan and one of hydroxylmethyl glycinate and one of water we obtain: RNH-CHr OH + 2 Chit-NH 2 Hydroxymethyl glycine _ . Chit-NH-CHrNH-Chit+ H20 + RNH2 reticulated chitosan + Water+ glycine Where the reacti on goes only versus the formation of reticulated chitosan. Differently it happens rn most of me thylols where it seems to establish an eq uilibrium between the methylol and methylene glycol in solution: AIM The aim of this study was to evaluate the prope rty of an innovati ve glyco-c hitosa n and/or PCA-chitosan gel to increase hydration, e lasticity and antioxidant potential of the skin , to restore the skin lipid content and eventually to decrease inflammati on and skin irritation pote ntial alle viating sy mptoms of dry skin during a 8 weeks treatment course. (+H20) ~ CH 20 lii (-H 0) HO-CH2 - OH methylene glycol (+ RNH2) .. . (- R-NH2) R-NH-CHz-OH +H 20 N-methylol + water 53 Envlfonment Fnendly Green Chem1cots MATHERIALS ANO METHODS EXPERIMENTAL DESIGN MATERIALS PRE - TEST For thi s study was used a g lycochi tosan gel as base (glycolic acid and ch itosan), and/or a PCA chitosa n (pyrrol idon carboxylic acid and chitosan) preserved by a derivative of glyc ine, fundamenta l a minoacid in cuta neous biology. T hese three products, being of natural origi n, could be s urely classified as "green compou nds" (2 1-23) METHOD SUBJECTS IN THE STUDY T he two-month tria! was a random ized doublebl ind-placebo-contro ll ed study carried out fo r 8 weeks on 60 dry skinn ed female volun teers, aged 32-43 wi th a moderate xeros is of g rade 5 according to Dahl (24). Surface lipids, s kin hydratio n and TEWL (25,26) were detected by the 3C System® (Dermotech, Italy). Ski n elastic ity and softness were evaluated by the De rmafl ex® A (Cortex Technology, Denmark). (27) Antiox idant potential was evalua ted by measure me nt of s kin hydroperoxides (28) meanwhil e irritation potenti al and the anti-i nflammato ry activity were investigated both by the SDS challenge tests and the Pyrexal Erythe ma test (29), using a lso the C hromameter®C 200. Before starting the experiment, the erythema tes t was done in a dermatologica! office in order to check if the ge l would perfor m a lso an eventual anti-infla mmato ry act ivity. T h is experime ntation was tested on the volunteers' back of 20 people onl y, a week before starting the study, according to the methods re ported. No vo lunteers used othe r top ica! treatments w ithin the two weeks or syste mic drug of diet s upple ments within the 4 weeks before starting the s tud y. A li the s ubjects gave their writte n informed consent in accordance with the ethics of cosmetics experimentation. The quantity of sodium-hydroxymethyl glycinate was always consta nt for each sample and was prev iously mixed with the chitosan solution. Neither the operator no r the subjects were ab le to ide ntify the ass ig ned product. The gel was applied twi ce daily a li over the face and on both the forearms. The treated a reas were always cleaned w ith the s upplied c leansing emulsion (Mav igen® latte). Fifteen days before starting the study a li other cosmeti cs were d isco ntinued. M easurements were performed at the I " day TEST T he s ubjects were randomly divided into six g roups of I O people each and received respectively: I GEL A glyco-chi tosan neutralized with gelati n-glycine at pH 4.8 Il GEL B glyco-chitosan neutralized with glycine/sodium glycinate at pH 4.8 111 GEL e glyco-chitosan neutralized with gelatin at pH 4.8 IV GEL o PCA-chitosan neutralized with gelatin-glycine at pH 4.8 V GEL E PCA-chitosan neutralized with glycine/sodi um-glycinate al pH 4.8 VI GEL F PCA-chitosan neutralized with gelatin at pH 4.8 54 P.Morganti, G. Fabrizi, F.Guarnen and C. Bruno (baseline) and at days 10'', 20,30,40,50,60'h (end of trea tment), and day 90'h always in the morning be tween 8 and l l a.m. 3C SYSTEM METHODOLOGV Quantitative mea sure ments of skin hydra tion , s urface lipids and TEWL were performed accordi ng to C a rdill o a nd Morga nti met hod (25 ) before the l st day (base line) a nd a fte r d ays I 0 ,2 0 ,30 ,40,50,60 (e nd of treatm e nt) and 90 days of treatment, a lways in the morning from 8 and 11 a.m. on skin cleaned the night before. This co mputeri zed methodology collects up to I O/ 15 measure me nts o ver 25 second sampling period and records the mean va lues, automatically sta ndardi z in g the e nvironme nta l conditions (RH = 50% t = 22°C). To alleviate the possibil ity of the patient phys iologic state, the othe r maj or factor-influe nc ing rate of wate r loss, it was asked to rest in the testing room for 30 minutes before measure me nts. Possible site -to-site variation was e li minated by rando m selection of treated sites. Skin hydration was assessed by measuri ng tota! capacitance of the horny layer and the values are ex pressed in 3C arbitrary units; skin !ipids, o b serv ed by a s p ec ia l fro s te d p la st ic fo il (l cm 2), are measured photo metrically and expressed as µ g/cm 2 ; TEWL was measured by a s pecia l 3C probe. It c ons ists of a cylindr ical o pen c hamber measuring syste m, d ia meter 14 mm., height I O mm. and two sensor units, conta ining a thin capacitance film transducer placed at 3 and 7 mm. distance from the skin. T EWL is calculated digitally as g/m 2 h. The instrume nt probe was a lways he ld pe rpendi cular to the skin surface a nd allowed to equ ilibrate for 20 sec. Ali the obtained results are expre ssed a s mea n values of the measurements performed on fou r different right or le ft skin sites (cheek, forehead, chin and nose). The obtained results are reported on fig. 1,2 and 3. SKIN HYORATION AFTER A lWO MONTH TOPICAL TREATMENTWITH GLYCO.CHITOSAN OR PCA·CHITOSAN GEL NEUTRALIZEO WITH OIFFERENT AMNOACIO MXTURE n =60 t =22 •c RH =50% • STA RTlNG :POINT 90 80 ·- w (/) 70 et w ir u 60 z 50 ~ 40 ~ o et o ir >z 30 :i: se (/) 20 1o ~ OAYS 20 30 ....._GEL e e -;.11-G E l A ( G lyco -C h ilo sa n w i h G el atin -G ly cfn n) _._G EL FIG. 1 10 (Glyco. C h lto s;, n wi1h Gela tin ) (G lyc o- C hilosan w lhGlyctne) 40 50 60 90 ~GE l F ( PC A-C h lto sa n w lth G elatl n ) GE LE (P CA-C h ito sanw it hGly ck1 e) -:>-GEL O (PCA -Ch ito san w ithGel a1i n-G ly cin e) All p vaJues are highly significant(p < 0.005) as baseline vaJues and as to groups 238 55 Envlfonment Friendly Green Chemrcols SUPERFICIAL SKIN LIPIDS AFTER A TWO MONTH TOPICAL TREA TMENTWITH GLYCO· CHITOSAN OR PCA·CHITOSAN GEL NEUTRALIZED WITH DIFFERENT AMNOACID M XTURE =60 n =22·c t RH =50% • STARTING :POINT 60 50 w (I) 40 <( w o:: (.) 30 ~ (I) o ii: 20 :::i z i: (I) 10 '*' DAYS 10 20 30 40 50 60 90 ~GEL F (PC A- C hltosa n wi1h Go l atln ) ~ G EL C (Glyco. C h l1o sa n wll h Ge latin ) G El E (PC A -Chltosa n w tth G ly cin e) -.fr-G EL B (G lyco- C ll itosa n w lh G ly cìn e) - """*"""G E L A (G l yco -C lt ito sa n w l:h G ehHin .e; lycln e) - 0 - G El O (P C A -C hilo sa n w it h G efatin..G lyck1 e) All p values are highly significant (p < 0.005) as baseline values and as to group_ s FIG. 2 TEWL after repeated SOS application on the forearm skin pre-treated with Glyco- Chitosan or PCA-Chitosan neutralized with a different aminoacid mixture. eomoanson between s1tes untreated 100 n =60 t =22 ·e RH =50% 90 80 70 .- 60 50 ns 40 ~ ~ n<:> 30 20 10 o - - GEL A (GlycoChitos an \'Jith Gelatm- Glycine 56 - ns A I Untreated SDStreated 1Control 2 Contro! FIG. 3 - ,--A---, - rt__ GEL D (PCA- GELB Chitos an (Glycowith Gelatin- Chitosan Glycine) with Glycine) - - - >--- - ~ ~ - - GEL E (PCA· GEL C GEL F (PCAG lycoChitosan Chito san \•Jith Chitosan with Ge latin) Gl>fcine) with Gelatin) All p values are hlghly significant (p < 0.005) as baseline PMorgant1. G FabrlZI. F.Guarnen and C Bruno SOS CHALLENGE TEST moved after 4 hours and reapplied to the same sites for two consecutive days for 4 hours each. After l hour and 24 hours of remava! of the last set of patches, the skin reaction was graded and evaluated by TEWL and Chromameter® measurements. The intensity of the irritation was assessed by visual scoring chromametry and TEWL measurements 5 hours a nd 24 hours after application of the patches. Thi s test is generally assessed to evaluate protective and anti-irritation potential efficacy of the studied products. Thereafter, one occlusive patch with 20% sodium dodecyl sulfate (S DS) solution were applied in a randomized way to left or right forearm of each subject for 3 days and different hours before and after 8 weeks of twice da ily treatme nt with the different kind of gels used. Two SDS treated and untreated sites were left as contro I. There was no further application of the studi ed gels after removal of the last patch. Patches were app lied to the pre-marked fo rearm areas, re- ( O = no-erythema; 0.5 = equivocai reaction; l = slig ht erythema; 2 = mod e rate, uniform erythema; 3 = intense; 4 = fiery redness with edema.) The obtained results are repo1ted on fig. 3 and 4. Chrornarneter® values a* ofthe forearrn skin after repeated SOS applications. Differences to baseline value of sites treated with Glyco-Chitosan or PCA-Chitosan gels 7 [a*] .../T~~~~~~-n_ e~ ut~ra ~l~ a~ ed :::....:..: w~ ff~ h~d~fffi~e~re~n~t=a~n1=m~o=ac~1=a~n~11='xt~u~re~.~~~~~~~ n 60 t 22 •e RH 50% = = = ns 6,5 ns 5,5 ns SOStretted control GELA(Glyco - GELO(PCA- GELB(Glyco- GELE(PCA- GELCGlyco- GELF(PCA - Chit o un with Chito san wilh Chitosan with Chito sa n wit h Chitos a n with C hitos•n with Gclatin -Glyclne Gcla t in- Glycinc) Glycine) Gelatin) Geletin) G lycinc) A and Dare highly significant vs Band E or e and F (p < 0.005) and as contrai FIG. 4 57 EnVlfonmenf Fflendly Green Chem1cots SKIN ELASTICITY SKIN HYDROPEROXIDES Skin e levatio n (elastic ity) was evaluated e lectronically (according to G .Gniadeck and Serup 27) by measu ring electric capacitance between skin surface and the electrode placed on the top of the s uction chamber o n the left or right forearm s of the treated vol unteers (s uc ti on 300 mbar, suction period 20 s, number of cycles 5). Measure me nts were performed o n I " day (base1ine) and at 10 ",20,30,40,50,60 days (end of treat111e nt) and at 90 days a lways in the morning between 8 and 11 a.111. The obtained res ults are re ported on Fig.5 Free radicals were evaluated according to Pugliese (28). A g lass cyl in der 111eas uring 51111. in diameter was placed on the skin and held snug ly, extracting the lipids by two different aliquots of 51111. portion of acetone. The lipid residue, dried under nitrogen st ream , was e111ul sifi ecl with sod iu m dodecyl sul fate, acetic acicl and thioba rbituric ac id. Th e supernatant extracted , read a t 531 n111 by a spectrophotometer, gave the concentration o f lipi d peroxides as MBA prec ursors. Meas ure ments were performed on I q day (baseli ne) and at 20,40,60 1" day (end of treat111e nt) and at 90 day always in the mo rning between 8 and 11 a. m. The obtai ned resu lts are reported on Fig.6 1 1 " 1 " 1 " SKIN ELASTICITY AFTER A TWO MONTH TOPICAL TREAlMENTWITH GLYCO-CHITOSAN OR PCA-CHITOSAN GEL NEUTRALIZEO WITH OIFFERENT AMNOACIO MXTURE n =60 t =22 •e RH =50% w (/) ci: 10 w a: u ~ >I- u ~ (/) ci: ..J w .,e OAYS 10 20 30 4--GEL C (Glyco - Chltosan vllth Gclalln ) _._GEI. B (Gtyco . Chltosan w i h G ty c lnc) ......... G EL A (Cilyco .Chilosa n w lh G elafn..G lyclne) FIG. 5 58 40 ~ GEL 50 60 F (P C A. Ch ilo sa n with G elatln) G E L E (P C A - Chlto sa n wilh G lycin e) - .:-G EL O (P C A .ChltosanwilhGelatin-Glyc"1e) Ali p values are highly significant (p < 0.005) as basellne values and as to groups 90 P.Morgonti, G Fobriz1, F.Guomen o n d C. Bruno ACETONE EXTRACTED LIPID PEROXIDE FROM FOREARM SKIN OF XEROTIC PEOPLE AFTER A TWO MONlH TOPICAL TREATMENTWITH GLYCO-CHITOSAN OR PCA-CHITOSAN GEL NEUTRALIZED WITH DIFFERENT AMNOACID MXTURE MDA mm/100 mglliquid 0.9 n =60 t =22 •e RH =50% 1"~~~~~~~~~~~~-=-'----=..:.._..::..::.:.:_~~~~~~~~~~~ Il 20 40 GO 90 DAYS ~GE L e (G lyco -C h ito sa n w ith G ela tin ) _._GEL e (Glyco - C hitosan wilh G ly clne) -+- G E L A (G l yco - C hi1osan with Gelatin -G lycin c) FIG. 6 - e -GE L f ( P C A -Chitosa n withGelatin) GEL D (PC A - C ll l1on n w lt h Ge l atin .G ly c inc) ~ G EL E PCA-Chitosan wlth G~clne) Ali p values are highly significant (p < 0.005) as baseline values and as to groups ERYTHEMA TEST This inflammation is obtained injecting intracutaneously O. I ml. Pyrexal (lipo-polysaccharide from sa lmo nella abortus equii)) into dorsal skin of the vo luntee r s ubjects, accordi ng to H e ilmeyer and Hiemejer (29) These bac terial pyrogens induce an inflammation. The morpholog ic sig ns take the form of a sharply defined erythema whose surface area is me as ured over time. Simultaneous application of an anti-inflammatory c re am inhibits its spread. By thi s injection 8 vials were induced in each s ubject. These were then topicall y treated in randomized s uccession with 0.2 ml. of the 6 different preparations and covered with transparent film. One of these areas re mained untreated to serve as a contro] and another was treated by 0.2 ml. of betamethasone va lerate O. I o/o and covered also with transparent fi lm. fn this way the erytherna is visible at ali times and can be measured through the film. The exte nt of the erythema was determined 6,8, 10 and 12 hours after application, the maxim um (a) and minimum (b) diameter be ing mea sured and the s urface area calcul ated by the elliptic formu la: p-axbxp 4 The efficacy was classified by determining the sum of the erythema surface areas from the 4th to the l 2th hour. 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