G Model
IJP 14380 1–4 International Journal of Pharmaceutics xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
International Journal of Pharmaceutics journal homepage: www.elsevier.com/locate/ijpharm
1 2
Influence of lidocaine hydrochloride and penetration enhancers on the barrier function of human skin
3 Q1
Kazumasa Hirata, Diar Mohammed, Jonathan Hadgraft, Majella E. Lane *
4 Q2
Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1 N 1AX, England, UK
A R T I C L E I N F O
A B S T R A C T
Article history: Received 27 August 2014 Received in revised form 2 October 2014 Accepted 4 October 2014 Available online xxx
Skin penetration enhancers (SPEs) are commonly employed in pharmaceutical and personal care products. These compounds transiently alter the barrier properties of the skin and we have previously investigated the effects of specific SPEs on skin barrier function in vivo. In the present study the effects of incorporation of an active pharmaceutical ingredient (API), lidocaine hydrochloride (LID HCl) in the SPEs previously studied were investigated. Solutions of LID HCl were prepared and applied to the volar forearm of human subjects with occlusion for 24 h. Subsequently, tape stripping and trans epidermal water loss (TEWL) measurements were conducted for treated and control sites. The activities of the desquamatory proteases, kallikrein 5 (KLK 5) and kallikrein 7 (KLK 7) and API content were also measured from the tape strips. The propylene glycol (PG) formulation increased TEWL significantly (p < 0.05) compared with the other SPEs and a mixture of the SPEs. However, only the isopropyl myristate (IPM) solution altered protease activity with a significant observed increase in kallikrein 5 (KLK 5). Incorporation of LID HCl appeared to ameliorate the effects of some of the SPEs on TEWL measurements compared with our previous study. Overall uptake of LID HCl into skin from the various formulations correlated very well with changes in TEWL. The findings should have implications for the choice of SPEs in topical and transdermal formulations, particularly where the skin barrier function of patients is already impaired for example in atopic eczema or psoriasis. ã 2014 Published by Elsevier B.V.
Keywords: Skin penetration enhancers Proteases Trans epidermal water loss Lidocaine hydrochloride
5
1. Introduction
6
Skin penetration enhancers are found in a wide range of pharmaceutical and cosmetic products. Their primary function is to enhance the delivery of actives to and through the skin. They achieve this via transient modulation of skin barrier function by a number of mechanisms; alteration of the solubility of a molecule in the stratum corneum (SC) or enhancement of the diffusion of the molecule through the SC because of perturbation of the lipid pathway, or both (Lane, 2013). We hypothesised that these transient effects should result in changes, at the molecular level, of the SC. Subsequently we reported that propylene glycol (PG) elevates the activity of the desquamatory protease, kallikrein 7 (KLK 7) as well as trans epidermal water loss (TEWL) when applied under occluded conditions for 24 h to the volar forearm of human subjects (Mohammed et al., 2014). In the present work we have extended our previous study to examine the effects of simple formulations of a model active pharmaceutical ingredient (API), lidocaine hydrochloride (LID
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
* Corresponding author. Tel.: +44 207 7535821; fax: +44 870 1659275. E-mail address: [email protected] (M.E. Lane).
HCl), on TEWL and protease activity. This API is used as the base or hydrochloride salt (Fig. 1) in a range of topical formulation Q3 including gels, patches and solutions; the therapeutic applications of the preparations are provision of surface anaesthesia or management of post herpetic neuralgia (PHN). Simple solutions of LID HCl in isopropyl myristate (IPM), PG, propylene glycol laurate (PGL), TranscutolTM (TC) as well as a mixture of the four vehicles were prepared. These solvents were selected as they were investigated in our previous study and they are commonly used in both topical and transdermal preparations. A mixture of the solvents was also selected for evaluation because SPEs may act synergistically (Lane, 2013). As TEWL and drug uptake into skin should also provide insight into the interaction of the formulations with skin these parameters were also examined.
23
2. Materials and methods
37
2.1. Materials
38
LID HCl, IPM and PG were purchased from Sigma–Aldrich, UK. PGL and TC were a kind gift from Gattefossé (St. Priest, France). Solutions of LID HCl were prepared at 5% w/v in PG, PGL and TC. LID HCl was used at its saturated solubility in IPM and in the IPM:PG:
39
http://dx.doi.org/10.1016/j.ijpharm.2014.10.012 0378-5173/ ã 2014 Published by Elsevier B.V.
Please cite this article in press as: Hirata, K., et al., Influence of lidocaine hydrochloride and penetration enhancers on the barrier function of human skin. Int J Pharmaceut (2014), http://dx.doi.org/10.1016/j.ijpharm.2014.10.012
24 25 26 27 28 29 30 31 32 33 34 35 36
40 41 42
G Model
IJP 14380 1–4 2 43 44 45 46 47 48 Q4 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77
K. Hirata et al. / International Journal of Pharmaceutics xxx (2014) xxx–xxx
PGL:TC mixture as the respective saturated solubility values were MIX TC > PGL IPM. However, these values do not necessarily indicate the extent to which the drug is actually therapeutically available in the skin as tape stripping cannot distinguish between crystallised drug or drug in solution. Using human skin mounted in Franz cells Trottet et al. (2004) had earlier noted that once PG is exhausted from formulations drug no longer permeates through the skin. More recently we have also shown that once PG permeation ceases, oxybutynin no longer permeates in human skin, likely because of drug crystallisation in the skin (Santos et al., 2010). When the values of LID HCl uptake into skin, normalised to protein content, are plotted against the relative changes in TEWL following application of the correlations an excellent linear correlation is obtained (Fig. 6).
224
4. Conclusions
241
The present work examines the effects of simple solutions of LID HCl in commonly used SPEs on the biophysical and molecular properties of skin and expands on our previous study which focussed on the SPEs themselves. PG formulations with LID HCl were found to alter TEWL compared with the other formulations but not to the same extent as PG alone. Only IPM formulations altered protease activity resulting in increased KLK 5 activity. There are reports of elevated KLK 5 and KLK 7 activity in diseased skin and our previous work confirmed increased KLK 7 activity following exposure to PG alone. However, this is the first report of elevated KLK 5 activity following application of a simple topical formulation. An excellent correlation was obtained for drug uptake in skin and changes in TEWL values. Taken together with our previous study the results reported here should have implications for the selection of SPEs used in the formulation of topical preparations for patients or consumers with impaired skin barrier function. However, it is important to note the small sample size studied here and further work with larger numbers of subjects should provide further insight into the clinical significance of the observations reported.
242
Acknowledgement
262
Dr Kazumasa Hirata wishes to acknowledge Maruho Ltd. Q5 (Japan) for the award of Ph D funding.
263
References
265
Aps, C., Reynolds, F., 1976. The effect of concentration on vasoactivity of bupivacaine and lignocaine. Br. J. Anaesth. 48, 1171–1174. Bouwstra, J.A., Perschier, L.J.C., Brussee, J., Boddk, H.E., 1989. Effect on N-alkylazacycloheptan-2-ones including azone on the thermal behaviour of human SC. Int. J. Pharm. 52, 47–54. Bouwstra, J.A., de Vries, M.A., Gooris, G.S., Bras, W., Brussee, J., Ponec, M., 1991. Thermodynamic and structural aspects of the skin barrier. J. Controlled Release 15, 209–220. Bouwstra, J.A., Gooris, G.S., Salomons-de Vries, M.A., van der Spek, J.A., Bras, W., 1992. Structure of human SC as a function of temperature and hydration: a wide-angle X-ray diffraction study. Int. J. Pharm. 84, 205–216. Brinkmann, I., Müller-Goymann, C.C., 2003. Role of isopropyl myristate: isopropyl alcohol and a combination of both in hydrocortisone permeation across human stratum corneum. Skin Pharmacol. Appl. Skin Physiol. 16, 393–404. Gioia, F., Celleno, L., 2002. The dynamics of transepidermal water loss (TEWL) from hydrated skin. Skin Res. Technol. 8, 178–186. Goodman, M., Barry, B.W., 1989. Lipid-protein-partitioning (LPP) theory of skin enhancer activity: finite dose technique. Int. J. Pharm. 57, 29–40. Lane, M.E., 2013. Skin penetration enhancers. Int. J. Pharm. 447, 12–21. Leopold, C.S., Lippold, B.C., 1995. An attempt to clarify the mechanism of the penetration enhancing effects of lipophilic vehicles with differential scanning calorimetry (DSC). J. Pharm. Pharmacol. 47, 276–281.
266 267 268 269 270 271 272 273 274
Please cite this article in press as: Hirata, K., et al., Influence of lidocaine hydrochloride and penetration enhancers on the barrier function of human skin. Int J Pharmaceut (2014), http://dx.doi.org/10.1016/j.ijpharm.2014.10.012
225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240
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275 276 277 278 279 280 281 282 283 284 285 286
G Model
IJP 14380 1–4 4 287 288 289 290 291 292 293 294 295 296 297 298
K. Hirata et al. / International Journal of Pharmaceutics xxx (2014) xxx–xxx
Mohammed, D., Matts, P.J., Hadgraft, J., Lane, M.E., 2011a. Depth profiling of stratum corneum biophysical and molecular properties. Br. J. Dermatol. 164, 957–965. Mohammed, D., Matts, P.J., Hadgraft, J., Lane, M.E., 2011b. Influence of aqueous cream BP on corneocyte size, maturity, skin protease activity, protein content and transepidermal water loss. Br. J. Dermatol. 164, 1304–1310. Mohammed, D., Hirata, K., Hadgraft, J., Lane, M.E., 2014. Influence of skin penetration enhancers on skin barrier function and skin protease activity. Eur. J. Pharm. Sci. 51, 118–122. Muizzuddin, N., Hellemans, L., Van Overloop, L., Corstjens, H., Declercq, L., Maes, D., 2010. Structural and functional differences in barrier properties of African American, Caucasian and East Asian skin. J. Dermatol. Sci. 59, 123–128. Santos, P., Watkinson, A.C., Hadgraft, J., Lane, M.E., 2010. Oxybutynin permeation in skin: the influence of drug and solvent activity. Int. J. Pharm. 384, 67–72.
Trottet, L., Merly, C., Mirza, M., Hadgraft, J., Davis, A.F., 2004. Effect of finite doses of propylene glycol on enhancement of in vitro percutaneous permeation of loperamide hydrochloride. Int. J. Pharm. 274, 213–219. Voegeli, R., Heiland, J., Doppler, S., Rawlings, A.V., Schreier, T., 2007. Efficient and simple quantification of SC proteins on tape strippings by infrared densitometry. Skin Res. Technol. 13, 242–251. Voegeli, R., Rawlings, A.V., Breternitz, M., Doppler, S., Schreier, T., Fluhr, J.W., 2009. Increased stratum corneum serine protease activity in acute eczematous atopic skin. Br. J. Dermatol. 161, 70–77. Waton, J., Boulanger, A., Trechot, P.H., Schmutz, J.L., Barbaud, A., 2004. Contact urticaria from EMLA cream. Contact Dermatitis 51, 284–287. Willatts, D.G., Reynolds, F., 1985. Comparison of the vasoactivity of amide and ester local anaesthetics. An intradermal study. Br. J. Anaesth. 57, 1006–1011.
Please cite this article in press as: Hirata, K., et al., Influence of lidocaine hydrochloride and penetration enhancers on the barrier function of human skin. Int J Pharmaceut (2014), http://dx.doi.org/10.1016/j.ijpharm.2014.10.012
299 300 301 302 303 304 305 306 307 308 309 310 311
IJP 14380 1–4 International Journal of Pharmaceutics xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
International Journal of Pharmaceutics journal homepage: www.elsevier.com/locate/ijpharm
1 2
Influence of lidocaine hydrochloride and penetration enhancers on the barrier function of human skin
3 Q1
Kazumasa Hirata, Diar Mohammed, Jonathan Hadgraft, Majella E. Lane *
4 Q2
Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1 N 1AX, England, UK
A R T I C L E I N F O
A B S T R A C T
Article history: Received 27 August 2014 Received in revised form 2 October 2014 Accepted 4 October 2014 Available online xxx
Skin penetration enhancers (SPEs) are commonly employed in pharmaceutical and personal care products. These compounds transiently alter the barrier properties of the skin and we have previously investigated the effects of specific SPEs on skin barrier function in vivo. In the present study the effects of incorporation of an active pharmaceutical ingredient (API), lidocaine hydrochloride (LID HCl) in the SPEs previously studied were investigated. Solutions of LID HCl were prepared and applied to the volar forearm of human subjects with occlusion for 24 h. Subsequently, tape stripping and trans epidermal water loss (TEWL) measurements were conducted for treated and control sites. The activities of the desquamatory proteases, kallikrein 5 (KLK 5) and kallikrein 7 (KLK 7) and API content were also measured from the tape strips. The propylene glycol (PG) formulation increased TEWL significantly (p < 0.05) compared with the other SPEs and a mixture of the SPEs. However, only the isopropyl myristate (IPM) solution altered protease activity with a significant observed increase in kallikrein 5 (KLK 5). Incorporation of LID HCl appeared to ameliorate the effects of some of the SPEs on TEWL measurements compared with our previous study. Overall uptake of LID HCl into skin from the various formulations correlated very well with changes in TEWL. The findings should have implications for the choice of SPEs in topical and transdermal formulations, particularly where the skin barrier function of patients is already impaired for example in atopic eczema or psoriasis. ã 2014 Published by Elsevier B.V.
Keywords: Skin penetration enhancers Proteases Trans epidermal water loss Lidocaine hydrochloride
5
1. Introduction
6
Skin penetration enhancers are found in a wide range of pharmaceutical and cosmetic products. Their primary function is to enhance the delivery of actives to and through the skin. They achieve this via transient modulation of skin barrier function by a number of mechanisms; alteration of the solubility of a molecule in the stratum corneum (SC) or enhancement of the diffusion of the molecule through the SC because of perturbation of the lipid pathway, or both (Lane, 2013). We hypothesised that these transient effects should result in changes, at the molecular level, of the SC. Subsequently we reported that propylene glycol (PG) elevates the activity of the desquamatory protease, kallikrein 7 (KLK 7) as well as trans epidermal water loss (TEWL) when applied under occluded conditions for 24 h to the volar forearm of human subjects (Mohammed et al., 2014). In the present work we have extended our previous study to examine the effects of simple formulations of a model active pharmaceutical ingredient (API), lidocaine hydrochloride (LID
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
* Corresponding author. Tel.: +44 207 7535821; fax: +44 870 1659275. E-mail address: [email protected] (M.E. Lane).
HCl), on TEWL and protease activity. This API is used as the base or hydrochloride salt (Fig. 1) in a range of topical formulation Q3 including gels, patches and solutions; the therapeutic applications of the preparations are provision of surface anaesthesia or management of post herpetic neuralgia (PHN). Simple solutions of LID HCl in isopropyl myristate (IPM), PG, propylene glycol laurate (PGL), TranscutolTM (TC) as well as a mixture of the four vehicles were prepared. These solvents were selected as they were investigated in our previous study and they are commonly used in both topical and transdermal preparations. A mixture of the solvents was also selected for evaluation because SPEs may act synergistically (Lane, 2013). As TEWL and drug uptake into skin should also provide insight into the interaction of the formulations with skin these parameters were also examined.
23
2. Materials and methods
37
2.1. Materials
38
LID HCl, IPM and PG were purchased from Sigma–Aldrich, UK. PGL and TC were a kind gift from Gattefossé (St. Priest, France). Solutions of LID HCl were prepared at 5% w/v in PG, PGL and TC. LID HCl was used at its saturated solubility in IPM and in the IPM:PG:
39
http://dx.doi.org/10.1016/j.ijpharm.2014.10.012 0378-5173/ ã 2014 Published by Elsevier B.V.
Please cite this article in press as: Hirata, K., et al., Influence of lidocaine hydrochloride and penetration enhancers on the barrier function of human skin. Int J Pharmaceut (2014), http://dx.doi.org/10.1016/j.ijpharm.2014.10.012
24 25 26 27 28 29 30 31 32 33 34 35 36
40 41 42
G Model
IJP 14380 1–4 2 43 44 45 46 47 48 Q4 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77
K. Hirata et al. / International Journal of Pharmaceutics xxx (2014) xxx–xxx
PGL:TC mixture as the respective saturated solubility values were MIX TC > PGL IPM. However, these values do not necessarily indicate the extent to which the drug is actually therapeutically available in the skin as tape stripping cannot distinguish between crystallised drug or drug in solution. Using human skin mounted in Franz cells Trottet et al. (2004) had earlier noted that once PG is exhausted from formulations drug no longer permeates through the skin. More recently we have also shown that once PG permeation ceases, oxybutynin no longer permeates in human skin, likely because of drug crystallisation in the skin (Santos et al., 2010). When the values of LID HCl uptake into skin, normalised to protein content, are plotted against the relative changes in TEWL following application of the correlations an excellent linear correlation is obtained (Fig. 6).
224
4. Conclusions
241
The present work examines the effects of simple solutions of LID HCl in commonly used SPEs on the biophysical and molecular properties of skin and expands on our previous study which focussed on the SPEs themselves. PG formulations with LID HCl were found to alter TEWL compared with the other formulations but not to the same extent as PG alone. Only IPM formulations altered protease activity resulting in increased KLK 5 activity. There are reports of elevated KLK 5 and KLK 7 activity in diseased skin and our previous work confirmed increased KLK 7 activity following exposure to PG alone. However, this is the first report of elevated KLK 5 activity following application of a simple topical formulation. An excellent correlation was obtained for drug uptake in skin and changes in TEWL values. Taken together with our previous study the results reported here should have implications for the selection of SPEs used in the formulation of topical preparations for patients or consumers with impaired skin barrier function. However, it is important to note the small sample size studied here and further work with larger numbers of subjects should provide further insight into the clinical significance of the observations reported.
242
Acknowledgement
262
Dr Kazumasa Hirata wishes to acknowledge Maruho Ltd. Q5 (Japan) for the award of Ph D funding.
263
References
265
Aps, C., Reynolds, F., 1976. The effect of concentration on vasoactivity of bupivacaine and lignocaine. Br. J. Anaesth. 48, 1171–1174. Bouwstra, J.A., Perschier, L.J.C., Brussee, J., Boddk, H.E., 1989. Effect on N-alkylazacycloheptan-2-ones including azone on the thermal behaviour of human SC. Int. J. Pharm. 52, 47–54. Bouwstra, J.A., de Vries, M.A., Gooris, G.S., Bras, W., Brussee, J., Ponec, M., 1991. Thermodynamic and structural aspects of the skin barrier. J. Controlled Release 15, 209–220. Bouwstra, J.A., Gooris, G.S., Salomons-de Vries, M.A., van der Spek, J.A., Bras, W., 1992. Structure of human SC as a function of temperature and hydration: a wide-angle X-ray diffraction study. Int. J. Pharm. 84, 205–216. Brinkmann, I., Müller-Goymann, C.C., 2003. Role of isopropyl myristate: isopropyl alcohol and a combination of both in hydrocortisone permeation across human stratum corneum. Skin Pharmacol. Appl. Skin Physiol. 16, 393–404. Gioia, F., Celleno, L., 2002. The dynamics of transepidermal water loss (TEWL) from hydrated skin. Skin Res. Technol. 8, 178–186. Goodman, M., Barry, B.W., 1989. Lipid-protein-partitioning (LPP) theory of skin enhancer activity: finite dose technique. Int. J. Pharm. 57, 29–40. Lane, M.E., 2013. Skin penetration enhancers. Int. J. Pharm. 447, 12–21. Leopold, C.S., Lippold, B.C., 1995. An attempt to clarify the mechanism of the penetration enhancing effects of lipophilic vehicles with differential scanning calorimetry (DSC). J. Pharm. Pharmacol. 47, 276–281.
266 267 268 269 270 271 272 273 274
Please cite this article in press as: Hirata, K., et al., Influence of lidocaine hydrochloride and penetration enhancers on the barrier function of human skin. Int J Pharmaceut (2014), http://dx.doi.org/10.1016/j.ijpharm.2014.10.012
225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240
243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261
264
275 276 277 278 279 280 281 282 283 284 285 286
G Model
IJP 14380 1–4 4 287 288 289 290 291 292 293 294 295 296 297 298
K. Hirata et al. / International Journal of Pharmaceutics xxx (2014) xxx–xxx
Mohammed, D., Matts, P.J., Hadgraft, J., Lane, M.E., 2011a. Depth profiling of stratum corneum biophysical and molecular properties. Br. J. Dermatol. 164, 957–965. Mohammed, D., Matts, P.J., Hadgraft, J., Lane, M.E., 2011b. Influence of aqueous cream BP on corneocyte size, maturity, skin protease activity, protein content and transepidermal water loss. Br. J. Dermatol. 164, 1304–1310. Mohammed, D., Hirata, K., Hadgraft, J., Lane, M.E., 2014. Influence of skin penetration enhancers on skin barrier function and skin protease activity. Eur. J. Pharm. Sci. 51, 118–122. Muizzuddin, N., Hellemans, L., Van Overloop, L., Corstjens, H., Declercq, L., Maes, D., 2010. Structural and functional differences in barrier properties of African American, Caucasian and East Asian skin. J. Dermatol. Sci. 59, 123–128. Santos, P., Watkinson, A.C., Hadgraft, J., Lane, M.E., 2010. Oxybutynin permeation in skin: the influence of drug and solvent activity. Int. J. Pharm. 384, 67–72.
Trottet, L., Merly, C., Mirza, M., Hadgraft, J., Davis, A.F., 2004. Effect of finite doses of propylene glycol on enhancement of in vitro percutaneous permeation of loperamide hydrochloride. Int. J. Pharm. 274, 213–219. Voegeli, R., Heiland, J., Doppler, S., Rawlings, A.V., Schreier, T., 2007. Efficient and simple quantification of SC proteins on tape strippings by infrared densitometry. Skin Res. Technol. 13, 242–251. Voegeli, R., Rawlings, A.V., Breternitz, M., Doppler, S., Schreier, T., Fluhr, J.W., 2009. Increased stratum corneum serine protease activity in acute eczematous atopic skin. Br. J. Dermatol. 161, 70–77. Waton, J., Boulanger, A., Trechot, P.H., Schmutz, J.L., Barbaud, A., 2004. Contact urticaria from EMLA cream. Contact Dermatitis 51, 284–287. Willatts, D.G., Reynolds, F., 1985. Comparison of the vasoactivity of amide and ester local anaesthetics. An intradermal study. Br. J. Anaesth. 57, 1006–1011.
Please cite this article in press as: Hirata, K., et al., Influence of lidocaine hydrochloride and penetration enhancers on the barrier function of human skin. Int J Pharmaceut (2014), http://dx.doi.org/10.1016/j.ijpharm.2014.10.012
299 300 301 302 303 304 305 306 307 308 309 310 311
