Anti-acne and Tolerance Assessment of a Cleanser Containing Salicylic acid, Gluconolactone and Niacinamide

Cao, Yu; Ai, Yunfei; Yu Cao; Yunfei Ai

doi:10.20402/ajbc.2024.0015

Asian J Beauty Cosmetol > Volume 22(3); 2024 > Article

살리실산, 글루코노락톤, 나이아신아마이드를 함유한 클렌저 제품의 여드름 방지 및 내약성 평가

Research Article

Asian J Beauty Cosmetol 2024; 22(3): 383-391.

Published online: September 27, 2024

DOI: https://doi.org/10.20402/ajbc.2024.0015

살리실산, 글루코노락톤, 나이아신아마이드를 함유한 클렌저 제품의 여드름 방지 및 내약성 평가

조우^1,^2,³, 예운비^4,^*

¹상하이 교통대학교 의과대학 신화병원 피부질환 진단 및 치료센터, 상하이, 중국

²상하이 교통대학교 부속 신화병원 피부과, 상하이, 중국

³상하이 교통대학교 의과대학 피부과 연구소, 상하이, 중국

⁴로레알 중국 피부과 및 미용 사업부, 상하이, 중국

Anti-acne and Tolerance Assessment of a Cleanser Containing Salicylic acid, Gluconolactone and Niacinamide

Yu Cao^1,^2,³, Yunfei Ai^4,^*

¹Dermatology Center, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China

²Department of Dermatology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China

³Institute of Dermatology, Shanghai Jiaotong University School of Medicine, Shanghai, China

⁴L'Oréal (China) Co., Ltd., Shanghai, China

针对含有水杨酸、葡萄糖酸内酯和烟酰胺洁面产品的抗痘和耐受性评估

曹宇^1,^2,³, 艾云飞^4,^*

¹上海交通大学医学院附属新华医院皮肤疾病诊治中心，上海，中国

²上海交通大学附属新华医院皮肤科，上海，中国

³上海交通大学医学院皮肤病研究所，上海，中国

⁴欧莱雅中国皮肤科学美容事业部，上海，中国

^*Corresponding author: Yunfei Ai, L'Oréal (China) Co., Ltd., No.1601 Nanjing West Road, Jing'an District, Shanghai 200040, China. Tel.: +86 21 5200 8512 Email: levin.ai@outlook.com

Received March 10, 2024 Revised June 24, 2024 Accepted September 5, 2024

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

요약

목적

여드름은 심리적 고통을 유발하고 삶의 질을 크게 저하시킬 가능성이 있다. 보통 여드름 치료에는 클렌저가 일반적으로 사용되지만, 그 효과를 뒷받침하는 임상적 증거는 여전히 제한적이다. 본 연구는 살리실산, 글루코노락톤, 나이아신아마이드를 함유한 클렌저의 항여드름 효과와 저자극성을 탐구하는 것입니다.

방법

두 그룹의 참가자를 모집하여, 한 그룹은 지성 여드름 피부를 가진 43명으로 구성되었으며, 제품 사용 4주 후 이들의 염증성 병변, 비염증성 병변 및 피지 함량을 측정하였다. 다른 그룹에는 민감성 피부를 가진 39명으로 구성되었으며, 제품 사용 2주 후 객관적인 자극 지표와 주관적인 자극 지표를 평가하였다.

결과

지성 여드름 피부에 레티놀, 나이아신아미드, 세라마이드가 함유된 클렌저를 4주간 사용한 후, 염증성 여드름 병변 수와 비염증성 여드름 병변 수 모두 유의미한 감소하였으며, 피부 피지 함량도 유의미하게 감소하였다. 민감한 피부에 2주 동안 사용한 후, 주관적 및 객관적 자극 매개변수 모두에서 상당한 개선이 관찰되었다.

결론

살리실산, 글루코노락톤, 나이아신아마이드를 함유한 클렌저는 민감한 피부에도 사용할 수 있을 만큼 순하면서도 여드름 증상을 효과적으로 개선할 수 있다고 사료된다

핵심용어: 클렌저 제품, 여드름, 민감성 피부, 살리실산, 나이아신아마이드

Abstract

Purpose

Acne has potential to cause psychological distress and significantly diminish one's quality of life. Although washing and over-the-counter cleansers are commonly used in the treatment of acne vulgaris, clinical evidence supporting their effectiveness is still limited. The main focus of this research is to explore anti-acne effectiveness and mildness of a cleanser containing salicylic acid, gluconolactone, and niacinamide.

Methods

We recruited two groups of participants. One group consisted of 43 individuals with oily acne-prone skin, and we measured their inflammatory lesions, non-inflammatory lesions, and sebum content after 4 weeks of product usage. The other group included 39 individuals with sensitive skin, and we assessed objective irritation parameters and subjective irritation parameters after 2 weeks’ product usage.

Results

After 4 weeks of using cleanser containing retinol, niacinamide and ceramides on oily acne-prone skin, significant reductions were observed in both inflammatory acne lesions count and non-inflammatory acne lesions count, while there was also a significant decrease in skin sebum content. After two weeks of use on sensitive skin, significant improvements were observed in both subjective and objective irritation parameters.

Conclusion

In summary, a cleanser containing salicylic acid, gluconolactone and niacinamide can effectively improve acne symptoms while being gentle enough for use on sensitive skin.

Keywords: Cleanser, Acne, Sensitive skin, Salicylic acid, Niacinamide

中文摘要

目的

痤疮可能会引起心理压力，并降低患者的生活质量。尽管清洁常被用于治疗寻常痤疮，但支持其有效性的临床证据仍然有限。本研究目的主要是探索含有水杨酸、葡萄糖酸内酯和烟酰胺清洁产品的抗痤疮效果和温和性。

方法

我们招募了两组参与者。一组由43名油性易长痘的志愿者组成，我们在他们使用产品4周后测量了他们的炎症性损伤、非炎症性损伤和皮脂含量。另一组包括39名敏感皮肤的志愿者，我们在他们使用产品2周后评估了客观刺激和主观刺激参数。

结果

在油性易长痘的皮肤上使用含有水杨酸、葡萄糖酸内酯和烟酰胺的清洁产品4周后，观察到炎症性痤疮计数和非炎症性痤疮计数都有显著减少，同时皮肤皮脂含量也有显著下降。在敏感皮肤上使用2周后，无论是主观还是客观刺激参数都有显著改善。

结论

含有水杨酸、葡萄糖酸内酯和烟酰胺的清洁产品可以有效地改善痤疮症状，同时足够温和，适合敏感皮肤使用。

关键词: 清洁产品, 痤疮, 敏感皮肤, 水杨酸, 烟酰胺

Introduction

Acne, a highly prevalent skin condition among adolescents, ranks as the fourth most common motive for doctor visits among individuals aged 11 to 21 in the USA (Ziv et al., 1999). Acne is estimated to impact approximately 9.4% of the global population, with the highest prevalence observed among adolescents (Tan & Bhate, 2015). The burden of disease associated with acne vulgaris has a worldwide distribution and has been consistently increasing in prevalence over time within this specific population.

The fundamental therapeutic approaches in acne management involve regulating sebum secretion, addressing abnormal keratinocyte cornification within hair follicles, and utilizing bactericidal agents (Mohsin et al., 2022). As a result, anti-inflammatory agents, bactericidal agents, and agents that control keratinization have been employed in acne treatment. Salicylic acid (SA) is believed to dissolve intercellular lipids in the outermost layer of the skin (stratum corneum) and break down comedones by dissolving surface lipids between skin cells (Lee & Kim, 2003). Similarly, the mechanism of action of gluconolactone involves promoting exfoliation by reducing the cohesion between corneocytes in the basal layer, thus helping to prevent follicular occlusion (Jarząbek-Perz et al., 2023). Niacinamide can reduce the symptoms of acne by controlling sebum and being anti-inflammatory (Kaymak & Onder, 2008).

Furthermore, cleansers aid in the improvement of acne by effectively clearing hair follicle plugs and preventing the obstruction of follicles (Magin et al., 2005). Patients commonly believe that poor hygiene contributes to acne and up to 70% incorporate cleansers as part of their acne treatment regimen (Veraldi et al., 2016). However, evidence for their clinical benefit is not well known. Here the main focus of this research is to explore the anti-acne effectiveness and mildness of a cleanser containing salicylic acid, gluconolactone, and niacinamide.

Materials and Methods

1. Subjects

2. Exclusion and inclusion criteria

1) The former group (for oily acne-prone skin)

The former group’s exclusion criteria were as follows:

-Subjects under acute attack of facial contact dermatitis and sensitive dermatitis;

-Subjects under dermatologist treatment/care;

-Vitamin A or its derivatives treatment within 3 months prior to this visit.

The former group’s inclusion criteria were as follows:

-Chinese female, 18 to 50 years of age;

-Facial acne grade 1-2 (IGA scale);

-Non - inflammatory not less than 10 capsules, inflammatory not less than 5 capsules (no more than 5 mm nodules on face, and assessment area excluding nose);

-Sebumeter value on forehead>100 μg/cm².

2) The latter group (for sensitive skin)

The latter group’s exclusion criteria were as follows:

-Having been diagnosed with known allergies to facial skin care products;

-Breastfeeding, pregnant, or planning to become pregnant during the study according to subject self-report.

The latter group’s inclusion criteria were as follows:

-Chinese male and female, 18 to 45 years of age (including 18 and 45);

-With oily or acne-prone skin;

-Self-percieved sensitive skin.

All subjects were informed and gave their consent before enrollment. The study has been approved by SGS Ethics Committee (No. 2023046).

3. Test substance

The treatment cleanser is the amino acid surfactant-based cleanser that contains 0.45% salicylic acid, 1% gluconolactone, 2% niacinamide and a blend of three essential ceramides i.e., ceramide 1,3,6-II (ceramide EOP, ceramide NP, ceramide AP).

Specifically, the ingredient list for cleanser is as follows:

Aqua/Water, Sodium Lauroyl Sarcosinate, Cocamidopropyl Hydroxysultaine, Glycerin, Niacinamide, Gluconolactone, Sodium Methyl Cocoyl Taurate, PEG-150 Pentaerythrityl Tetrastearate, Ceramide NP, Ceramide AP, Ceramide EOP, Carbomer, Calcium Gluconate, Salicylic Acid, Sodium Benzoate, Sodium Lauroyl Lactylate, Cholesterol, Phenoxyethanol, Disodium EDTA, Tetrasodium EDTA, Hydrolyzed Hyaluronic Acid, Phytosphingosine, Xanthan Gum, Ethylhexylglycerin.

Apply the cleanser 1-2 times per day with warm tap water and a gentle, circular motion for rinsing.

4. Test place and environment

The study was conducted in Shanghai. The tests were carried out in a constant humidity and temperature room (temperature 21±1℃, humidity 50%±5RH%).

5. Clinical assessment (for oily acne-prone skin)

Clinical assessment of acne lesion counts parameters at baseline, weeks 2 and 4 include counting below inflammatory lesions and non-inflammatory lesions. Dermatologists counted and recorded the number of close comedones (whiteheads), open comedones (blackheads), papules, and pustules on the face as Table 1 shows.

At baseline, the subjects who had mild to moderate acne (score 1-2 on IGA scale), non-inflammatory not less than 10 capsules, inflammatory not less than 5 capsules (no more than 5 mm nodules on face) on the global face was enrolled into the study.

The Global Acne Assessment score was assessed at the indicated locations using an IGA scale according to the following numerical definitions as follows:

0=clear skin with no inflammatory or noninflammatory lesions

1=almost clear; rare noninflammatory lesions with no more than one small inflammatory lesion

2=mild severity; some noninflammatory lesions with no more than a few inflammatory lesions (papules/pustules only, no nodular lesions)

3=moderate severity; up to many noninflammatory and may have some inflammatory lesions; but no more than one small nodular lesions

4=severe; up to many noninflammatory and inflammatory lesions; but no more than a few nodular lesions

6. Sebumeter measurements (for oily acne-prone skin)

Sebumeter measurements were performed at baseline, day 1, weeks 1, 2 and 4, every visit before face cleaning. Triplicate Sebumeter measurements were taken on adjacent, nonoverlapping sites on the center of each subject’s forehead. The measurement sites at each time point were the same. The Sebumeter SM 815 (Courage+Khazaka electronic GmbH, Köln, Germany) measures sebum quantity on the skin using a photometric method.

7. Tolerance assessment (for sensitive skin)

The tolerance was examined by a board-certified dermatologist. For subjects with sensitive skin, a dermatological evaluation was performed at baseline and after 14 days of use. Local cutaneous tolerability was evaluated globally on each subject’s face. The following scales and definitions were used for tolerability evaluations:

1) Objective irritation parameters

Erythema: 0=None; 1=Mild; 2=moderate; 3=Severe.

Dryness: 0=None; 1=Mild; 2=Moderate; 3=Severe.

2) Subjective irritation parameters

Burning:0=None; 1=Mild; 2=Moderate; 3=Severe.

Stinging: 0=None;1=Mild; 2=Moderate; 3=Severe.

Itching: 0=None; 1=Mild; 2=Moderate; 3=Severe.

Tightness:0=None; 1=Mild; 2=Moderate; 3=Severe.

Tingling:0=None; 1=Mild; 2=Moderate;3=Severe.

8. Biostatistics and data management

Calculate the changes in each parameter after use by subtracting the post-use measurement from the pre-use measurement. The paired t-test or Wilcoxon signed-rank test was used to test the null hypothesis that the mean change value before use was zero. Statistical analysis was performed using SPSS 28.0 with a significance level of α=0.05 and a two-tailed test.

Results

1. Clinical assessment (for oily acne-prone skin)

1) Open comedones count

Compared with baseline, at week 2, the open comedones count decreased by 1.35 significantly with 56% subjects improved (p<0.05). At week 4, the open comedones count decreased by 4.07 significantly (p<0.05) with 81% subjects improved (Figure 1A). This indicates that a facial cleanser containing salicylic acid, gluconolactone, and niacinamide has a significant effect on improving open comedones.

2) Close comedones count

Compared with baseline, at week 2, the close comedones count decreased by 1.67 significantly with 67% subjects improved (p<0.05). At week 4, the close comedones count decreased by 2.84 significantly (p<0.05) with 74% subjects improved (Figure 1B). This indicates that a facial cleanser containing salicylic acid, gluconolactone, and niacinamide has a significant effect on improving the count of closed comedones.

3) Total non-inflammatory lesions count

Compared with baseline, at week 2, the total noninflammatory lesions count decreased by 3.02 significantly with 79% subjects improved (p<0.05). At week 4, the total noninflammatory lesions count decreased by 6.91 significantly (p<0.05) with 88% subjects improved (Figure 1C). This suggests that a facial cleanser containing salicylic acid, gluconolactone, and niacinamide has a significant effect on improving the count of total non-inflammatory lesions.

4) Papules count

Compared with baseline, at week 2, the papules count decreased by 1.14 significantly with 58% subjects improved (p<0.05). At week 4, the papules count decreased by 1.81 significantly (p<0.05) with 77% subjects improved (Figure 2A). This indicates that a facial cleanser containing salicylic acid, gluconolactone, and niacinamide has a significant effect on improving the count of papules.

5) Pustules count

Compared with baseline, at week 2, the pustules count decreased by 0.81 significantly with 49% subjects improved (p<0.05). At week 4, the pustules count decreased by 0.47 non-significantly with 47% subjects improved (Figure 2B).

6) Total inflammatory lesions count

Compared with baseline, at week 2, the total inflammatory lesions count decreased by 1.95 significantly with 74% subjects improved (p<0.05). At week 4, the total inflammatory lesions count decreased by 2.28 significantly (p<0.05) with 77% subjects improved (Figure 2C). This suggests that a facial cleanser containing salicylic acid, gluconolactone, and niacinamide has a significant effect on improving the count of total inflammatory lesions.

2. Skin sebum (for oily acne-prone skin)

Compared with baseline, at week 2, the skin sebum decreased by 12.51% significantly with 98% subjects improved (p<0.05). At week 4, the skin sebum decreased by 27.08% significantly (p<0.05) with 100% subjects improved (Figure 3). This indicates that a facial cleanser containing salicylic acid, gluconolactone, and niacinamide has a significant inhibitory effect on skin sebum.

3. Tolerance assessment (for sensitive skin)

Comparing with D 0, at D 14, the clinical score of erythema decreased by 0.46 significantly (p<0.05), the clinical score of dryness/scaling decreased by 0.44 significantly (p<0.05), the clinical score of peeling decreased by 0.05 non-significantly, the clinical score of burning sensation decreased by 0.44 significantly (p<0.05), the clinical score of stinging decreased by 0.21 significantly (p<0.05), the clinical score of itching decreased by 0.51 significantly (p<0.05), the clinical score of tightness decreased by 0.59 significantly (p<0.05), and the clinical score of tingling decreased by 0.18 significantly (p<0.05, Table 2).This suggests that a facial cleanser containing salicylic acid, gluconolactone, and niacinamide significantly improves most subjective and objective irritation parameters.

Discussion

Acne is a multifactorial condition influenced by various factors. It often involves excessive sebum production and enlargement of the sebaceous glands, leading to the formation of microcomedones due to the accumulation of keratin within the follicular walls. Topical application of active ingredients, such as salicylic acid, in the treatment of acne has been widely reported (Akhavan & Bershad, 2003). Nevertheless, the connection between facial cleansing and acne has not been definitively established. Recent studies have indicated that active ingredients, such as salicylic acid, in cleanser formulations can effectively penetrate the skin and exert their effects (Davies, 2015). Our research findings indicate that a cleanser formulated with salicylic acid, gluconolactone, ceramide, and niacinamide can successfully reduce the occurrence of acne lesions and regulate sebum production (Figure 4). Salicylic acid not only lyses comedones through the dissolution of intercellular surface lipids but also inhibits Propionibacterium acnes, the bacteria associated with acne (Blaskovich et al., 2019). Similarly, gluconolactone works by reducing the cohesion between corneocytes in the basal layer, promoting exfoliation and preventing follicular occlusion. In addition, gluconolactone is milder and has fewer side effects compared to benzoyl peroxide (Hunt & Barnetson, 1992). Niacinamide is capable of regulating sebum production and exhibits anti-inflammatory properties (Draelos et al., 2006).

Over the past decade, an increasing volume of research has emphasized the role of inflammation in all stages of acne, including the subclinical phase preceding comedone formation (Tanghetti, 2013). In addition to that, acne is also associated with compromised skin barrier (Schachner et al., 2023). Therefore, a cleanser targeted for acne should be gentle and preferably contain soothing ingredients. Previous studies have shown that using amino acid-based cleansers can effectively reduce acne lesion counts (Isoda et al., 2015; Stringer et al., 2018). Similarly, our study reveals a notable decrease in various irritation parameters following the use of the products on sensitive skin, indicating its potential for mitigating skin irritation and exhibiting anti-inflammatory properties. This may be because the cleanser primarily consists of aminoacid surfactants, making it gentler than regular soap-based cleansers (Ananthapadmanabhan, 2019). In addition, the product contains ceramides and previously in vitro studies have indicated that ceramides possess reparative properties for the skin barrier and can reduce the expression of inflammatory enzymes and cytokines, leading to anti-inflammatory effects (Song et al., 2017). Recent research has specifically emphasized the lower levels of ceramides observed in acne-prone skin, highlighting the potential significance of ceramides in the context of acne (Pappas et al., 2018).

Our study has several limitations, and one aspect that could be improved is increasing the sample size to enhance the statistical power of the findings. Furthermore, the present study did not assess more skin physiological parameters, including skin hydration, transepidermal water loss (TEWL), and changes in skin substance metabolism. In future research, integrating non-invasive skin instruments and skin metabolomics would be valuable for investigating the modifications associated with cleanser application.

Conclusion

The main focus of this study is to investigate the anti-acne effectiveness and gentleness of a cleanser containing salicylic acid, gluconolactone, and niacinamide. The results indicate that after 4 weeks of using the cleanser on oily, acne-prone skin, notable decreases were observed in both the count of inflammatory acne lesions and non-inflammatory acne lesions, along with a significant reduction in skin sebum content. When used for two weeks on sensitive skin, significant improvements were noted in both subjective and objective irritation parameters. In conclusion, a cleanser incorporating salicylic acid, gluconolactone, and niacinamide can effectively ameliorate acne symptoms while remaining suitable for use on sensitive skin.

NOTES

Author's contribution

Y.C.: Main author, responsible for clinical evaluation and consultation.

Y.A.: The initiator and sponsor of the research; responsible for the development of research proposal, etc.

Author details

Yu CAO (Researcher), Dermatology Center, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, No.1665 Kongjiang Road, Shanghai 200092, China; Yunfei Ai (CeraVe China Medical Manager), L'Oréal (China) Co., Ltd., No.1601 Nanjing West Road, Jing'an District, Shanghai 200040, China.

Figure 1.

Effect of cleanser on non-inflammatory lesions count.

(A) Open comedones count; (B) Close comedones count; (C) Total non-inflammatory lesions count. The data were expressed as M±SD and the significant differences were analyzed by the paired t-test or Wilcoxon signed-rank test method. M±SD, mean±standard deviation.^*means p<0.05.

Figure 2.

Effect of cleanser on inflammatory lesions count.

(A) Papules count; (B)Pustules count; (C) Total inflammatory lesions count. The data were expressed as M±SD and the significant differences were analyzed by the paired t-test or Wilcoxon signed-rank test method. M±SD, mean±standard deviation.^*means p<0.05.

Figure 3.

Effect of cleanser on skin sebum.

The data were expressed as M±SD and the significant differences were analyzed by the paired t-test or Wilcoxon signed-rank test method. M±SD, mean±standard deviation.^*means p<0.05.

Figure 4.

Photographs of a representative acne subject.

Table 1.

Different type counts of acne lesions

Type	Description
Close comedones (whiteheads)	Closed comedones with a size of a needle tip to needlehead, white in color, and not easily expressible with a non-prominent opening.
Open comedones (blackheads)	Visible enlarged pores with a plug that is parallel to or slightly elevated above the skin surface, presenting as black or brown open comedones.
Papules	Localized, palpable, superficial elevations with a palpable, solid lesion.
Pustules	Inflammatory skin lesion with redness at the base and topped with pus-filled.

Table 2.

Results of tolerance assessment

Parameter	Mean		Change value	Significant p value
Parameter	D 0	D 14	D 14	D 14
Erythema	0.79	0.33	-0.46	<0.05
Dryness/scaling	0.69	0.26	-0.44	<0.05
Peeling	0.15	0.10	-0.05	0.750
Burning sensation	0.46	0.03	-0.44	<0.05
Stinging	0.21	0	-0.21	<0.05
Itching	0.51	0	-0.51	<0.05
Tightness	0.74	0.15	-0.59	<0.05
Tingling	0.18	0	-0.18	<0.05

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