Comparative Effect of Gromwell (Lithospermum erythrorhizon) Extract and Borage Oil on Reversing Epidermal Hyperproliferation in Guinea Pigs

Abstract

To compare the systemic efficacy of borage oil (Borago officinalis: BO) and gromwell (Lithospermum erythrorhizon), two plant species of the Boraginaceae family, epidermal hyperproliferation was induced in guinea pigs by a hydrogenated coconut oil diet for 8 weeks. Subsequently, guinea pigs were fed diets of BO (group HBO), organic extract (group HGO), or water extract (group HGW) of gromwell for 2 weeks. In groups HGO and HGW, proliferation scores and the level of ceramides, the major lipid maintaining epidermal barrier, were similar with those in normal control group BO fed BO diet for 10 weeks. Despite accumulation of 15-hydroxyeicosatrienoic acid (15-HETrE), the potent anti-proliferative metabolite of gamma-linolenic acid (GLA: major polyunsaturated fatty acid in BO), the reversal of epidermal hyperproliferation and the ceramide level of group HBO were less than those of groups HGO and HGW. Taken together, our data demonstrate that gromwell is more effective in reversing epidermal hyperproliferation with a marked increase in ceramides.

Dietary Supplementation of Gamma-Linolenic Acid Improves Skin Parameters in Subjects with Dry Skin and Mild Atopic Dermatitis

“…3 and 4 A: plasma GLA 0.3 , C: plasma DGLA 1.2 , E: plasma AA 6.2 ; the stratifi ed groups Daily GLA intake was 0.06mg in the control group and 200mg in the GLA group. 1 Values are means SD.…”

“…The epidermal barrier is composed of intercellular lipid lamellae with ceramides, cholesterol and fatty acids in the stratum corneum. Any barrier disruption increases transepidermal water loss TEWL and epidermal hyperproliferation, both of which are observed in abnormal skin conditions such as essential fatty acid defi ciency 1,2 .…”

The Effect of Gromwell (Lithospermum erythrorhizon) Extract on the Stratum Corneum Hydration and Ceramides Content in Atopic Dermatitis Patients

“…As for bioactive components, naphthaquinones such as shikonin and its derivatives have been characterized mostly in organic extracts of gromwell 12,46,47 which have antiproliferative activities in various cancer cells with several mechanisms of action, such as inhibition of DNA topoisomerase, induction of apoptosis by caspase-3 activation, and anti-proliferative activity with down-regulation of activated extracellular signal-regulated kinase (ERK) and activation of phosphorylated Jun N-terminal kinase (JNK) [48][49][50][51] . In previous study, both the organic extract and the water extract of gromwell showed anti-proliferative activity, which suggests that well-characterized bioactive components such as napthaquinones or fatty acids might be extracted with water as well as with organic solvents 10 . In this study, to examine the localization and distribution of substances within the SC, skin surface tape stripping with adhesive tape is a widely accepted and used method.…”

“…Depletion of ceramides has been suggested to be an etiological factor for epidermal barrier disruption, the decrease of SC hydration, increased TEWL and epidermal hyperproliferation 10 . We focused on reduced water content rather than TEWL for evaluating the effect of gromwell extract on SC ceramide.…”

“…When the systemic efficacy of gromwell is examined in hyperproliferative epidermis of essential fatty acid (EFA) deficient guinea pigs in our previous study, gromwell supplementation was effective in reversing epidermal hyperproliferation in parallel with a marked increase of ceramides 10 . Although the systemic efficacy of gromwell on skin was reported in a few studies including our previous study 10,11 , most of efficacies of gromwell in skin such as antiproliferative, antimicrobial and anti-inflammatory activities have been reported mostly based on topical application 11,12 and only limited information is available for the systemic efficacy of gromwell on skin. In this study, we investigated whether supplementation of gromwell may improve the epidermal level of hydration and ceramides in patients with AD.…”