• Toxicological Research
• /
• v.16 no.1
• /
• pp.89-94
• /
• 2000

Alpha-hydroxy acid(AHA) are used in cosmetic products as a pH adjuster, mild exfoliant and humectant-skin conditioner. Cosmetics containing higher concentration (30%) and lower pH (3.0) of AHA can cause side effects if it is applied without the prescription. For providing information on the safety of AHA and on human risk assessments we studied skin irritation effect of glycolic acid, one of the most commonly used AHA in guinea pigs. The skin irritation by glycolic acid was increased in a dose(10% to 70%), acidity (pH 2.5 to 5.5.) and length of exposure dependent manner (for up to 14 days), respectively. The combination treatment with UVB (0.4 or 3.0 J/$cm^2$) increased glycolic acid-induced skin irritation. Histological examination showed that hyperplasia of non-inflammatory cells in the epidermis of skin treated with high dose of glycolic acid (pH 3.0). There results show that glycolic acid increased skin irritation in a dose, length of exposure and pH dependent manner, respectively, in guinea pig, and the combination with UVB increased glycolic acid-induced skin irritation. The cell proliferation of non-inflammatory cell may be involved in high doses of glycolic acid-induced skin irritation. Long-term application of more than 30% of glycolic acid (pH 3.0) may cause skin irritation.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.31 no.3 s.52
• /
• pp.219-236
• /
• 2005

Glycolic acid, an alpha-hydroxy acid derived from fruit and milk sugars, has been commonly used as a cosmetic ingredient since it was known to have photo-protective, anti-inflammatory effects, and anti-oxidant effect in UV-irradiated skin. However, little has been know about the functional role of glycolic acid on UV-induced skin cell proliferation. It was previously found that glycolic acid inhibited UV-induced skin tumor development in hairless mouse. As a possible mechanism of glycolic acid on the UV-induced skin tumor development, the ability of glycolic acid to inhibit the UVB-induced cell growth and possible mechanisms were investigated. Glycolic acid treatment attenuated the UV-induced cell proliferation and apoptotic cell death in the skin. In vitro study, glycolic acid inhibited the UVB-induced cell growth and apoptotic death through inhibiting caspase-3 activity. These results suggest that glycolic acid may exert the Inhibitory effect on the UVB-induced skin tumor development by regulating cell growth and apoptotic cell death.

• Toxicological Research
• /
• v.17 no.1
• /
• pp.59-63
• /
• 2001

In this study, we compared skin response between Hartley guinea pig and New Zealand white rabbit. New Zealand white rabbit was treated by a glycolic acid (0, 8, 24, 40, 56 mg/$cm^2$) and UVB (0, 0.4, 3.0 J/$cm^2$) for 14 days. Skin irritation by glycolic acid and UVB were increased in dose and time-dependent manners, and the combination treatment of UVB increased glycolic acid-induced skin irritation. Comparison the skin irritation index between guinea pig and rabbit showed that guinea pig was much more sensitive to glycolic acid and UVB. This study indicated that selection of reliable species of animal could be considered in chemical-induced skin irritation study.

• YAKHAK HOEJI
• /
• v.40 no.2
• /
• pp.155-162
• /
• 1996

Hyperkeratinization is a dermatologic disorder, which is due to the increase of corneocyte cohesion force. Glycolic acid, an alpha hydroxy acid(AHA), has been used to breakdown the hyperkeratinization processes. However, it has a problem of skin irritation when applied topically, due to the strong acidity especially in high concentration. A molecular optimization of glycolic acid has been tried to reduce the skin irritation by the way of prodrug formation. Ethyl glycolate was synthesized by the esterification of glycolic acid with ethanol in acidic conditions in the presence of sulfuric acid, and examined under the spectroscopic trials, such as UV, IR, $^1H$-NMR, and GC-MS. The physicochemical and biopharmaceutical properties of the prodrug were also evaluated. Through the toxicological tests of both skin irritation and eye mucous irritation, it has been proved that ethyl glycolate was less irritant than glycolic acid, since the pH value of synthetic prodrug was higher than that of glycolic acid. In the penetration test through nude mouse skin by diffusion cell, ethyl glycolate was continuously hydrolyzed to glycolic acid, which was assayed form the receptor compartment. It was obtained that the penetrated amount of ethyl glycolate was five times higher than that of glycolic acid. These results suggest that ethyl glycolate might be a successful prodrug of glycolic acid to reduce the skin irritation and to increase the skin penetration as well.

• Journal of Biomedical Engineering Research
• /
• v.9 no.1
• /
• pp.37-46
• /
• 1988

Synthetic biodegradable polymers are of great interest for biomedical applications such as surgical sutures and drug delivery systems. The copolymers of ${alpha}-amino$ acids and ${alpha}-hydroxy$ matrices having the required permeability for drugs. Poly (glycine.co-lactic acid) and poly (glycine-co-glycolic acid) have been synthesized by ring-opening polymerization. Morpholine-2, 5-diane, lactide, and glycolid have been used as starting materials for polydepsipeptides. The synthesized monomers and copoylmers have been identified by NMR and FT-lR spectrophotometer. The thermal properties and glass transition temperatures ($T_g$) of the copolymers have been measured by differential scanning calorimetry. The $T_g$ values of poly (glycine-co-lactic acid) and poly (glycine co.glycolic acid) are increased with increasing mole fraction of morpholine-2, 5-dione in the copolymers.

• Proceedings of the SCSK Conference
• /
• 2003.09b
• /
• pp.519-523
• /
• 2003

Alpha hydroxy acid (AHA) includes a group of organic acids found in natural foods such as sugarcane (glycolic acid), milk (lactic acid), apples (malic acid) and oranges (citric acid). Earlier studies demonstrated the effect of AHAs on the skin by diminishing the adhesiveness of the corneal layer and increasing the viable epidermal thickness. Recent data suggest that AHAs have some effects on the dermal component of skin and even affect the aging process of the skin. A previous study revealed increased collagen production by treatment with glycolic acid among AHAs in vitro. However, the mechanism of the regulation of collagen production by glycolic acid was unclear. In present study, we tried to demonstrate the effect of glycolic acid on human dermal fibroblasts and to unveil the mechanism of regulation of collagen production by glycolic acid in human dermal fibroblasts: proliferation of fibroblasts and collagen synthesis and degradation by collagenases in fibroblasts. Our results suggested that glycolic acid had no effect on proliferation and cytotoxicity of adult human dermal fibroblasts. However, glycolic acid not only induced the increase of the collagen synthesis in human dermal fibroblasts at lower concentration than 0.1 % but also inhibited MMP-2 activity of human dermal fibroblast in the range between 0.01 and 0.4% and MMP-9 activity of human dermal fibroblast in the range between 0.06 and 0.09%. In summary, our results suggest that glycolic acid may increase wrinkle reduction partially by both increase in collagen synthesis and decrease in collagen degradation.

• Polymer(Korea)
• /
• v.26 no.3
• /
• pp.300-306
• /
• 2002

To study the effect of polymer compositions on the cell adhesion, copolymers of 3-(S)-[(dodecyloxycarbonyl) methyl]-1,4-dioxane-2,5-dione (DMD) and L-lactide were made, where DMD was synthesized form L-malic acid (L-MA) and glycolic acid. Furthermore, the copolymerization of DMD and L-lactide was performed using tin(II) octanoate as a catalyst. As a result of fixing RGD on the copolymer films, the cell adhesive peptide was fixable on the surface of the film. It was found out that the amount of fixation of RGD also increases by the increase in the amount of MA unit introduction. Since it is gradually decomposed over a long period and neither remains nor accumulation occurs, glycolic acid-$\beta$-dodecylmalate -lactic acid (D-PGML) is greatly expected as a potential biomaterial with improved slow degradability.

• Proceedings of the Korean Fiber Society Conference
• /
• 2000.04a
• /
• pp.241-244
• /
• 2000

• Polymer(Korea)
• /
• v.31 no.3
• /
• pp.228-232
• /
• 2007

This purpose of this study is to enhance the hydrolysis of poly (butylene succinate-co-L-lactate) (PBSL) and poly [(R) -3-hydroxybutylate] (PHB), to develop materials with advanced medical absorbability and environmental suitability. The first method involves increasing the bioabsorbability of poly (glycolic acid) (PGA) in the core of the fibrous complex, while the second method involves making a complex fiber containing PBSL and PHB in the outer layer for improving environmental degradability Improvement in the hydrolysis of PBSL and PHB due to glycolic acid occurs by hydrolytic behavior of PGA. The drawing supporting the resulting PBSL/PGA fiber was executed at $65^{\circ}C$, where the orientation is well arranged in crystal form. Obtaining a PHB/PGA complex fiber in the proper crystal orientation at $50^{\circ}C$ was not possible since the arranged crystal orientation was only identified in drawings from temperatures above $50^{\circ}C$. Also, it is necessary to execute a smooth surface to achieve an on-line drawing since unevenness occurs in the fibrous surface from an in-line drawing.

• Polymer(Korea)
• /
• v.31 no.3
• /
• pp.233-238
• /
• 2007

The purpose of the study is to apply composites of poly (glycolic acid) (PGA) with [poly(R) 3-hydroxybutyrate] (P3HB) or poly (butylenes succinate- co-L-lactate) (PBSL) as medical resorbable composite materials with the complement of hydrolysis rate of each component. As a result, it was confirmed that the PBSL/PGA and P3HB/PGA composite fiber were hydrolyzed in phosphate buffer solution. Also, it has been revealed that the degradation of PBSL/PGA are accelerated due to PGA producing glycolic acid which can act as a catalyst. In addition, the hydrolysis of PBSL/PGA was found to be accelerated by the presence of lipase PS. When the PBSL/PGA composite fiber was placed in the air, not much hydrolysis has proceeded. Also, it was confirmed that the P3HB/PGA composite fiber maintained proper tensile strength in the air. Therefore, these complex fibers can be adapted to use as environmentally suitable, medically absorbable composite materials.