ABSTRACT
ObjectiveTo compare the differences in resistance and structure of skin between acupoints and non-acupoints， and to study the difference in skin permeability characteristics of Corydalis Rhizoma total alkaloid patches （CTTP） after administration at Shenque acupoint and non-acupoint， so as to provide experimental support for its clinical acupoint application to prevent and treat chronic pain. MethodTaking corydaline （CD）， tetrahydropalmatine （THP） and corydalis L （CDL） as evaluation indexes， and the quantitative analysis was carried out by high performance liquid chromatography （HPLC）. The mobile phase was methanol-0.04 mol·L-1 phosphoric acid aqueous solution （70∶30， pH 6.0 adjusted with triethylamine）， the detection wavelength was 281 nm. In vitro transdermal test in Franz diffusion cell and in vivo transdermal test were used to study the skin permeability characteristics of CTTP through Shenque acupoint and non-acupoint administration. At the same time， the skin resistance between Shenque acupoint and non-acupoint was measured before and after the administration， and the distribution of the drug in each layer of the skin was compared by freezing sectioning， and visual verification was performed with fluorescence inverted microscope. ResultAfter 24 h of administration， the results of in vivo and in vitro experiments showed that the cumulative permeation and retention of CD， THP and CDL at Shenque acupoint skin were higher than those at non-acupoint skin （P<0.05， P<0.01）， the skin resistance of Shenque acupoint was lower than that of non-acupoint at all time points. The fluorescence microscopic observation results showed that the drug content of each layer of the skin was all Shenque acupoint>non-acupoint， indicating that the skin of Shenque acupoint had better effect on drug penetration and storage than non-acupoint. ConclusionThe 24 h cumulative permeation and retention of CTTP in Shenque acupoint skin are higher than those in non-acupoint skin， and the mechanism may be related to the thin skin， low electrical resistance and large number of hair follicle bodies at Shenque acupoint.
ABSTRACT
ObjectiveTo compare the differences in resistance and structure of skin between acupoints and non-acupoints， and to study the difference in skin permeability characteristics of Corydalis Rhizoma total alkaloid patches （CTTP） after administration at Shenque acupoint and non-acupoint， so as to provide experimental support for its clinical acupoint application to prevent and treat chronic pain. MethodTaking corydaline （CD）， tetrahydropalmatine （THP） and corydalis L （CDL） as evaluation indexes， and the quantitative analysis was carried out by high performance liquid chromatography （HPLC）. The mobile phase was methanol-0.04 mol·L-1 phosphoric acid aqueous solution （70∶30， pH 6.0 adjusted with triethylamine）， the detection wavelength was 281 nm. In vitro transdermal test in Franz diffusion cell and in vivo transdermal test were used to study the skin permeability characteristics of CTTP through Shenque acupoint and non-acupoint administration. At the same time， the skin resistance between Shenque acupoint and non-acupoint was measured before and after the administration， and the distribution of the drug in each layer of the skin was compared by freezing sectioning， and visual verification was performed with fluorescence inverted microscope. ResultAfter 24 h of administration， the results of in vivo and in vitro experiments showed that the cumulative permeation and retention of CD， THP and CDL at Shenque acupoint skin were higher than those at non-acupoint skin （P<0.05， P<0.01）， the skin resistance of Shenque acupoint was lower than that of non-acupoint at all time points. The fluorescence microscopic observation results showed that the drug content of each layer of the skin was all Shenque acupoint>non-acupoint， indicating that the skin of Shenque acupoint had better effect on drug penetration and storage than non-acupoint. ConclusionThe 24 h cumulative permeation and retention of CTTP in Shenque acupoint skin are higher than those in non-acupoint skin， and the mechanism may be related to the thin skin， low electrical resistance and large number of hair follicle bodies at Shenque acupoint.
ABSTRACT
Objective: To prepare the hydrogels using Bletilla striata polysaccharides (BSP) as groundmass and evaluate its properties. Methods: BSP were successfully extracted and characterized by Fourier Transform Infrared Spectrometer, thermogravimetric analysis, differential thermal analysis, and X-ray diffraction. The BSP was incorporated with Carbopol 940 to prepare hydrogels. Rheological behavior of the gels was investigated by rotational rheometer, skin permeation properties and bioactivities of BSP gels were evaluated by trans-epidermal water loss (TEWL) and blood coagulation examinations respectively using mice as model animals. Results: The BSP was pure with complete structure. The BSP gels showed the better viscoelasticity and physical strength from carbopol gel. The gels showed better skin permeation enhancement and hemostatic activity. Conclusion: This work demonstrates the skin permeation enhancement and plasma coagulation effects of BSP hydrogels, which show great potential in transdermal drug delivery system and wound dressing.
ABSTRACT
BACKGROUND: The major function of the skin is to prevent loss of water and electrolytes and transepidermal penetration of harmful materials. The stratum corneum is known to play a major role in the skin barrier function. Tape stripping (TS) with adhesive cellophane tape is one of the best method of removing the stratum corneum on the skin surface, and has been used in studies of the skin barrier function when investigating material distribution in the stratum corneum and transepidermal absorption of drugs. OBJECTIVE: This study was performed to evaluate the skin barrier function according to removal of the stratum corneum by TS. METHOD: Six vitiligo patients who had undergone autologous suction blister grafting were tested. Transepidermal water loss (TEWL) was measured on the normal skin of the buttocks in each patient after every fifth TS, plus on the skin where the entire epidermis had been removed by autologous suction blister grafting. We compared these two values and also examined morphological change of the stratum corneum after TS, by both light and electron microscope. RESULTS: The TEWL value slightly increased when TS was carried out up to 30 times, but greatly increased to 20g/m2h of TEWL when TS was done 30-40 times. Thereafter, no increase in TEWL was observed when TS was carried out up to 100 times. The pattern of TEWL according to numbers of TS approximately plotted a sigmoid curve. On average, there was about 88% impairment to the skin permeability barrier function after TS. When the TEWL increased to more than 70g/m2h over baseline TEWL, the stratum corneum was almost removed, as revealed by light and transmission electron microscope. CONCLUSION: The stratum corneum acts as a major skin barrier, and the mid to lower portion of the entire stratum corneum appears to play a significant role in the skin permeability barrier function.
Subject(s)
Humans , Absorption , Adhesives , Blister , Buttocks , Cellophane , Colon, Sigmoid , Electrolytes , Epidermis , Permeability , Skin , Suction , Transplants , VitiligoABSTRACT
BACKGROUND: The stratum corneum(SC) inhibits t,ransepidermal water loss and makes a permeability barrier against foreign materials, so strategies to overcome relative impermeability of the SC is very important in transdermal drug delivery. This includes occlusion, hydration, chemical permeation enhancers, iontophoresis and sonophoresis, Oleic acid, which is one of the cis-unsaturated fatty acid and chemical permeation enhancers, increases the permeability of the lipophilic molecules and polar miolecules through the SC. By spectrometry, calorimetry and the flux technique, the hypothesis that oleic acid does exist as a liquid within the SC lipids and enhances the transport of polar molecules across the SC by the formation of permeable interfacial defects within the SC lipid bilayers was suggested. Also, repeated application of oleic acid induces epidermal proliferation, hyperkeratosis and sebaceous gland hyperplasia', However the exact pathomechanism was not reported. OBJECTIVE: We carried out some research to observe the mechanism by which oleic acid in creases transdermal drug delivery and the effect to the skin permeability barrier and epidermis by repeated application. METHODS: In the repeated treatment group, hairless mice(6 to 8 weeks) were treated with oleic acid once a day for 7 days unilaterally, and in the single treatment group, only one time, Transepidermal water loss(TEWL) was checked at 24hour after 1, 3 and 7 days of treatment and at, 1 hour, 6 hours, 24 hours, 72 hours after single treatment. Biopsies were taken from treated and controlateral(control) sides immediately after the TEWL checks at each time for light microscopic(H & E stain) and electron microscopic studies. RESULTS: In the repeated treatment group, TEWL was increased by day and epidermal proliferation and hyperkeratosis were also increased. In the single treatment group, TEWL was highly increased in the treated site at 1 hour after treatment and decreased with time. By electronmicroscope, we observed dilated lacunae, intrcellular lipid structural abnormalities and loss of normal calcium gradient. CONCLUSION: The possible domains of the epidermis interacting with oleic acid as a penetration enhancer are the lacunae and liipid bilayer by EM. The suggested pathomechanism of the epidermal changes, epidermal proliferation and hyperkeratosis was increased DNA synthesis of epidermal cells by the loss of epidermal calcium gradient in chronic barrier impairment.