Anti-inflammatory effects of a topical preparation containing nicotinamide, retinol, and 7-dehydrocholesterol in patients with acne: a gene expression study

Casting New Light on the Retinol and Retinyl Palmitate Functions as Chemical Enhancers for Transdermal/Topical Drug Delivery

Retinol and retinyl palmitate, with excellent whitening and antioxidant activities, are widely used as essential functional ingredients in transdermal preparations and skincare products. Herein, for the first time, the influence and underlying mechanisms of retinol and retinyl palmitate on the skin penetration of caffeine are investigated. It is found that the penetration of caffeine is very significantly enhanced by retinol and retinyl palmitate with 2.83 and 2.57 folds, respectively. Mechanistic studies showed that they can disrupt the lipids of intercellular orderly arrangement and reduce the content of orthorhombic lattices in the skin, making the skin loose and the barrier function decreased. Furthermore, due to the formation of chemical bonds with the skin keratin, they have a strong affinity with the skin, changing the dense secondary structure of keratin with a reduced skin barrier effect. This study provides new evidence for the potential of retinol and retinyl palmitate as novel skin penetration enhancers with high safety that possess great potential for application in the transdermal delivery of pharmaceutical and cosmetic active substances.

Topical retinoids: Novel derivatives, nano lipid-based carriers, and combinations to improve chemical instability and skin irritation

BACKGROUND

Retinoids, defined as synthetic or natural derivatives of vitamin A, have been extensively studied as anti-aging molecules that are widely applied in cosmetics. However, due to their physicochemical property, retinoids are highly unstable and extremely sensitive to light, oxygen, and temperature. Moreover, topical application of retinoids often leads to cutaneous irritation. These instabilities and irritant properties of retinoids limit their application in cosmetic and pharmaceutical products.

AIM

Our study aimed to provide a systematic review to summarize the mechanisms underlying the instability and irritant properties of retinoids, as well as recent developments in addressing these challenges.

METHODS

A comprehensive PubMed search was conducted using the following keywords: retinoids, chemical instability, skin irritation, retinoid derivatives, nano lipid-based carriers, liposomes, penetration-enhancer vesicles, ethosomes, niosomes, nanoemulsions, solid lipid nanoparticles, vitamins, soothing and hydrating agents, antioxidants and metal chelator and retinol combinations. Relevant researches published between 1968 and 2023 and studies related to these reports were reviewed.

RESULTS

The development of new retinoid derivatives, the utilization of new delivery systems like nano lipid-based carriers and the combination with other compounds like vitamins, soothing agents, antioxidants and metal chelator have been explored to improve the stability, bioavailability, and toxicity of the retinoid family.

CONCLUSIONS

Through advancements in formulation techniques, structure modification of retinoid derivatives and development of novel nano lipid-based carriers, the chemical instability and skin irritation of retinoids has been mitigated, ensuring their efficacy and potency over extended periods.

Mechanistic Insights into the Multiple Functions of Niacinamide: Therapeutic Implications and Cosmeceutical Applications in Functional Skincare Products

Niacinamide (or nicotinamide) is a small-molecule hydrosoluble vitamin with essential metabolic functions in mammalian cells. Niacinamide has become a key functional ingredient in diverse skincare products and cosmetics. This vitamin plays a pivotal role in NAD+ synthesis, notably contributing to redox reactions and energy production in cutaneous cells. Via diversified biochemical mechanisms, niacinamide is also known to influence human DNA repair and cellular stress responses. Based on decades of safe use in cosmetics, niacinamide recently gained widespread popularity as an active ingredient which aligns with the "Kligman standards" in skincare. From a therapeutic standpoint, the intrinsic properties of niacinamide may be applied to managing acne vulgaris, melasma, and psoriasis. From a cosmeceutical standpoint, niacinamide has been widely leveraged as a multipurpose antiaging ingredient. Therein, it was shown to significantly reduce cutaneous oxidative stress, inflammation, and pigmentation. Overall, through multimodal mechanisms, niacinamide may be considered to partially prevent and/or reverse several biophysical changes associated with skin aging. The present narrative review provides multifactorial insights into the mechanisms of niacinamide's therapeutic and cosmeceutical functions. The ingredient's evolving role in skincare was critically appraised, with a strong focus on the biochemical mechanisms at play. Finally, novel indications and potential applications of niacinamide in dermal fillers and alternative injectable formulations were prospectively explored.

Method Development for Simultaneously Determining Indomethacin and Nicotinamide in New Combination in Oral Dosage Formulations and Co-Amorphous Systems Using Three UV Spectrophotometric Techniques

This research aims to develop methods for simultaneously determining indomethacin (IND) and nicotinamide (NCT) in binary mixtures, immediate-release capsules, sustained-release capsules, and co-amorphous systems, which were designed in 2021 to improve the solubility, dissolution rate, and stability of the amorphous state of indomethacin. Moreover, this new combination may have also other possible medical benefits. Therefore, there is a need to have simple, sensitive, and precise developed methods for simultaneous quantification analysis of IND/NCT in several different ratios. Three UV-spectrophotometry techniques were deployed: zero-crossing point in the second-order derivative, dual-wavelength in the first-order derivative, and ratio subtraction coupled with spectrum subtraction. The limit of detection and the limit of quantifications (LOD and LOQ) for IND were 0.41 and 1.25, 0.55 and 1.66, and 0.53 and 1.62 μg/mL, respectively, while for NCT were 0.53 and 1.59, 0.38 and 1.14, and 0.36 and 1.08 μg/mL, respectively. All methods were linear at least in the range of 2.5-40.0 μg/mL. All proposed methods were validated according to ICH guidelines and their application on the dosage formulations was carried out. Finally, the proposed methods were compared to a reference method for each IND and NCT, and no significant statistical variance was found.

Investigating material basis and molecular mechanism of Qing Cuo formula in the treatment of acne based on animal experiments, UPLC-LTQ-Orbitrap-MS and network pharmacology

CONTEXT

Qing Cuo Formula (QCF) is a traditional Chinese medicine for treating acne, but its active compounds and molecular mechanisms are unclear.

OBJECTIVE

To investigate the material basis and molecular mechanism of QCF.

MATERIALS AND METHODS

In vivo experiments were conducted on 60 male golden hamsters with damp-heat acne, with a blank group, a spironolactone group and 3 QCF administration groups (given high, medium and low doses) over a 30-day period. Serum androgen and inflammatory cytokine levels were tested by ELISA. In vitro, chemical compositions of QCF were investigated by UPLC-LTQ-Orbitrap-MS. Network pharmacology approaches were used to analyse the protein-protein interaction (PPI) network and QCF active compounds-intersection targets-acne network. GO enrichment and KEGG pathway analysis was conducted subsequently.

RESULTS

Low-dose QCF group (11.4 g/kg/day) showed significantly reduced levels of serum T (4.94 ± 0.36; 5.51 ± 0.36 ng/mL), DHT (6.67 ± 0.61; 8.09 ± 0.59 nmol/L), E2 (209.01 ± 20.92; 237.08 ± 13.94 pg/mL), IL-1α (36.84 ± 3.23; 44.07 ± 4.00 pg/mL) and FFA (128.32 ± 10.94; 148.00 ± 12.12 µmol/L) compared to the blank group (p < 0.05). In vitro experiments identified 75 compounds in QCF decoction, with 27 active compounds absorbed in serum. Network pharmacology identified 6 active components connecting 17 targets. GO enrichment and KEGG pathway analysis indicated that QCF's anti-acne targets mainly regulate extracellular matrix function, inflammatory processes, immune response and endocrine function.

CONCLUSIONS

This study provides evidence of the molecular mechanism and material basis of QCF in treating androgen-related damp-heat acne, paving the way for further research on its potential in treating other conditions related to damp-heat constitution.

Topical application of bacteriocins from Bacillus subtilis promotes Staphylococcus aureus decolonization in acneic skin and improves the clinical appearance of mild-to-moderate acne

Introduction

Patients with mild-to-moderate acne are frequently colonized by Staphylococcus aureus on their skin, which alters microenvironmental skin conditions and exacerbates disease symptoms. Bacteriocins produced by Bacillus subtilis may act as antimicrobial peptides against Gram-positive bacteria.

Aim

To investigate whether topical application of bacteriocins from B. subtilis could serve as a potential strategy for promoting S. aureus decolonization from acneic skin.

Material and methods

The research product was a cream formulation containing 1% bacteriocins from B. subtilis. First, we conducted a 60-day pilot study on the effect of topically applied bacteriocins from B. subtilis on the absolute abundance of S. aureus in 12 patients with mild-to-moderate acne. Second, we designed an 8-week, uncontrolled, open-label, multicentre clinical study to investigate whether the topical application of bacteriocins from B. subtilis reduces the number of inflammatory and non-inflammatory lesions, as well as Global Acne Grading Scale (GAGS) scores, in 373 patients with mild-to-moderate acne.

Results

At the microbiological level, quantitative PCR showed a decrease in the absolute abundance of S. aureus in acne areas after topical application of the research product for 60 days (-38%, p < 0.001). In the clinical study, the number of inflammatory and non-inflammatory lesions was found to decrease at 8 weeks by 59% (p < 0.001) and 58% (p < 0.001), respectively, compared with baseline. A 56% decrease was observed for GAGS scores.

Conclusions

Topical bacteriocins from B. subtilis can promote S. aureus decolonization in acneic skin, ultimately improving the clinical appearance of mild-to-moderate acne.

Delivery and diffusion of retinal in dermis and epidermis through the combination of prodrug nanoparticles and detachable dissolvable microneedles

To minimize chemical degradation of retinal, we graft this aldehyde on chitosan chains to make them self-assemble into pro-retinal nanoparticles (PRNs), which we then load into detachable dissolvable microneedles (DDMNs) made of 1:1 (by weight) hyaluronic acid/maltose. The presence of PRNs in the hyaluronic acid-maltose needle matrix also helps improve the microneedles' mechanical strength. Ex vivo administration of PRN-loaded DDMNs on fresh porcine ear skin shows, as observed by stereomicroscopic and confocal fluorescence microscopic analyses of the cross-sectioned tissue pieces, complete deposition followed by dissolution of the needles and diffusion of the PRNs in epidermis and dermis. Rats administered with a single dose of PRN-loaded DDMNs show significantly increased epidermal thickness as compared to rats administered with control DDMNs (no PRN). Both the PRN-loaded DDMNs and the control DDMNs produce no skin irritation in rats.

Effects of Low Temperature on Antioxidant and Heat Shock Protein Expression Profiles and Transcriptomic Responses in Crayfish (Cherax destructor)

Low temperature is a critical factor restricting the growth and survival of aquatic animals, but research on the mechanism of response to low temperature in Cherax destructor is limited. C. destructor is one of the most important freshwater crustaceans with strong adaptability in Australia, and it has been commercialized gradually in recent years. Here, growth indicators, antioxidant parameters, anti-stress gene expression, and transcriptome sequencing were used on crayfish following 8 weeks of low-temperature acclimation. The results showed that weight gain, length gain, and molting rates decreased as the temperature decreased. The activity of antioxidant enzymes decreased, while the content of antioxidant substances and the expression of anti-stress genes increased. Transcriptome sequencing identified 589 differentially expressed genes, 279 of which were upregulated and 310 downregulated. The gene functions and pathways for endocrine disorders, glucose metabolism, antioxidant defense, and immune responses were identified. In conclusion, although low-temperature acclimation inhibited the basal metabolism and immune ability of crayfish, it also increased the antioxidant substance content and anti-stress-gene expression to protect the organism from low-temperature damage. This study provided molecular insights into the study of low-temperature responses of low-temperature-tolerant crustacean species.

Enhancing Topical Pharmacotherapy for Acne and Rosacea: Vehicle Choices and Outcomes

The choice of vehicle is an important consideration in the treatment of acne and rosacea. Agents used to treat these common conditions may be limited by multiple factors, including poor stability during storage, limited residence time in the skin and follicular unit, and high potential for skin irritation. Novel drug delivery systems have been developed to address these problems, including microencapsulation, liposomal encapsulation, and the use of a variety of nanocarriers. New vehicle technologies for acne and rosacea treatments have appeared over the past 20 years and have somewhat improved stability, tolerability, and possibly efficacy. One of the latest vehicle technologies in acne and rosacea to enhance efficacy, stability, and tolerability is microencapsulation of benzoyl peroxide and tretinoin, which resulted in significant efficacy and good tolerability in patients with each of these two diseases. Other new vehicle technologies include a polymeric form of tretinoin and a microsphere product that combines tretinoin plus clindamycin. It is likely that there will be more reports of clinical success as experience with the rapidly evolving delivery technologies increases. This review summarizes drug delivery systems that have been developed with the aim of improving outcomes for patients being treated for either acne or rosacea. It also focuses, where possible, on formulations that have been evaluated in clinical studies.

Development and validation of derivative UV spectroscopic method for simultaneous estimation of nicotinamide and tretinoin in their binary mixtures and pharmaceutical preparations

An accurate, precise, sensitive, and simple spectroscopic method was developed and validated for simultaneous quantification analysis of tretinoin (TRT) and nicotinamide (NCT) with a ratio of 1:40 (TRT: NCT) in a synthetic mixture from dermal pharmaceutical preparations (solution and cream). Wavelengths were chosen in the first and second-order derivatives which are valid for the determination of NCT with the existence of TRT and excipients of the tested pharmaceutical preparations. Wavelength 253 nm was picked for the first-order derivative. Wavelengths 245 and 269 nm were picked for the second derivative. All previous wavelengths were zero-crossing points for TRT and its pharmaceutical preparations. Zero-order spectroscopy was used to determine TRT at the wavelength 348 nm, where no interference with NCT or any substance in the previous pharmaceutical preparation. The linearity range was studied and found to be 20–120 μg/mL and 0.5–5.0 μg/mL for NCT and TRT respectively. The correlation coefficient was 0.9995–0.9999 for NCT and 0.9998–0.9999 for TRT. The limit of detection (LOD) and the limit of quantification (LOQ) of NCT were 1.510 μg/mL and 4.590 μg/mL respectively at the wavelength 269 nm of the second-order derivative.

Nicotinamide Prevents Apolipoprotein B-Containing Lipoprotein Oxidation, Inflammation and Atherosclerosis in Apolipoprotein E-Deficient Mice

The potential of nicotinamide (NAM) to prevent atherosclerosis has not yet been examined. This study investigated the effect of NAM supplementation on the development of atherosclerosis in a mouse model of the disease. The development of aortic atherosclerosis was significantly reduced (NAM low dose: 45%; NAM high dose: 55%) in NAM-treated, apolipoprotein (Apo)E-deficient mice challenged with a Western diet for 4 weeks. NAM administration significantly increased (1.8-fold) the plasma concentration of proatherogenic ApoB-containing lipoproteins in NAM high-dose (HD)-treated mice compared with untreated mice. However, isolated ApoB-containing lipoproteins from NAM HD mice were less prone to oxidation than those of untreated mice. This result was consistent with the decreased (1.5-fold) concentration of oxidized low-density lipoproteins in this group. Immunohistochemical staining of aortas from NAM-treated mice showed significantly increased levels of IL-10 (NAM low-dose (LD): 1.3-fold; NAM HD: 1.2-fold), concomitant with a significant decrease in the relative expression of TNFα (NAM LD: −44%; NAM HD: −57%). An improved anti-inflammatory pattern was reproduced in macrophages cultured in the presence of NAM. Thus, dietary NAM supplementation in ApoE-deficient mice prevented the development of atherosclerosis and improved protection against ApoB-containing lipoprotein oxidation and aortic inflammation.

Predicting new indications of compounds with a network pharmacology approach: Liuwei Dihuang Wan as a case study

With the ever increasing cost and time required for drug development, new strategies for drug development are highly demanded, whereas repurposing old drugs has attracted much attention in drug discovery. In this paper, we introduce a new network pharmacology approach, namely PINA, to predict potential novel indications of old drugs based on the molecular networks affected by drugs and associated with diseases. Benchmark results on FDA approved drugs have shown the superiority of PINA over traditional computational approaches in identifying new indications of old drugs. We further extend PINA to predict the novel indications of Traditional Chinese Medicines (TCMs) with Liuwei Dihuang Wan (LDW) as a case study. The predicted indications, including immune system disorders and tumor, are validated by expert knowledge and evidences from literature, demonstrating the effectiveness of our proposed computational approach.

[Very high frequency ultrasound: New therapeutic method in aesthetic medicine and dermatology]

Very high frequency ultrasound (VHF-US) is new therapy method with a broad application spectrum in dermatology and aesthetic medicine. In this method, ultrasound waves with frequencies over 10 MHz, which were for a long time only used in ultrasound diagnostics, are applied for therapeutic purposes. Such US waves demonstrate specific biophysical efficiencies which warrant their application for the treatment of the skin efflorescences, chronic wounds and hypertrophic scars as well as in anti-aging and skin improvement procedures in aesthetic medicine. VHF-US can be applied not only for stand-alone treatments, but also as a supportive pre- and posttreatment method in combination with laser, radiofrequency currents, injection lipolysis, etc. as well as in aesthetic plastic surgery.

A comparative study of MMP-1, MMP-2, and TNF-α expression in different acne vulgaris lesions

Many inflammatory mediators and cytokines play important roles in the pathogenesis of acne vulgaris (AV). Information about the roles of these factors in the pathogenesis of the disease is limited. The purpose of this study was to evaluate levels of matrix metalloproteinase-1 (MMP-1), MMP-2, and tumor necrosis factor-α (TNF-α) in AV lesions. We selected 80 patients who presented at our dermatology department with AV. Their lesions included papules, pustules, nodules, and comedones. Each specimen was evaluated by histopathology with hematoxylin and eosin staining, and subsequently by immunohistochemical analysis for MMP-1, MMP-2, and TNF-α antibodies. A statistically significant difference between lesion groups emerged for MMP-1 (P = 0.012) and TNF-α (P = 0.029) scores. The MMP-1 score was highest in nodules and lowest in comedones. The TNF-α score was also highest in nodules but lowest in papules. We conclude that different levels of MMP expression can contribute to the development of different types of acne lesion and that the amount of TNF-α released may contribute to lesion development. Further studies of novel treatment modalities might evaluate the different clinical types of AV.

The role of topical dermocosmetics in acne vulgaris

Acne is a common chronic inflammatory disease and treatment modalities based on acne severity are well established. The role of dermocosmetics in dermatology, and in particular acne, is becoming more important as more research elucidates the mechanisms of action of products in the pathogenesis of acne. Dermocosmetics have the potential to be used as monotherapy or in combination with medical treatment. Therefore, it has become important for dermatologists to understand dermocosmetics to effectively and appropriately advise patients on their use. The objective of this review was to provide new insights into the role of traditional and novel ingredients in dermocosmetics for the treatment of acne, based on the authors' objective assessment of the published literature. The type of products discussed include: those which have a sebostatic effect, such as topical antioxidants and niacinamide; agents targeting abnormal keratinization, such as salicylic acid, lipo-hydroxy acid, alpha-hydroxy acids, retinol-based products and linoleic acid; agents targeting Propionibacterium acnes, such as lauric acid; and anti-inflammatory agents such as nicotinamide, alpha-linolenic acid and zinc salts. Despite the scientific advances in understanding these cosmetic ingredients, there still remains a lack of rigorous controlled studies in this area.

Formulation of tretinoin-loaded topical proniosomes for treatment of acne: in-vitro characterization, skin irritation test and comparative clinical study

Tretinoin (TRT) is a widely used retinoid for the topical treatment of acne, photo-aged skin, psoriasis and skin cancer which makes it a good candidate for topical formulation. Yet side effects, like redness, swelling, peeling, blistering and, erythema, in addition to its high lipophilicity make this challenging. Therefore, the aim of this study was the development of TRT-loaded proniosomes to improve the drug efficacy and to increase user acceptability and compliance by reducing its side effects. Nine formulae were prepared according to 3(2) factorial design and were evaluated for their morphology, vesicle size, entrapment efficiency (EE %), and% of drug released after 5 h. Hydrogel of the candidate formula, N8G (proniosomes prepared with 0.025% TRT, and Span60: cholesterol molar ratio of 3:1 and incorporated in 1% carbopol gel) was developed and evaluated for skin irritation test and clinical study in acne patients compared to marketed product. Candidate formula showed higher efficacy and very low irritation potential when compared to marketed product in human volunteers.

Polymorphisms in the promoters of MMP-2 and TIMP-2 genes in patients with acne vulgaris

Acne, a chronic inflammatory skin disease, can be seen at any age but it most often occurs in adolescents and young people. Several factors, including increased sebum production, abnormal cornification of the pilosebaceous units, proliferation of Propionibacterium acne, and extracellular matrix (ECM) remodeling, are thought to be associated with the pathogenesis of the acne. The remodeling of the ECM is regulated by a balance between matrix metalloproteinases (MMPs) and their inhibitors called tissue inhibitors of metalloproteinases (TIMPs). The current study investigated the potential association between MMP-2 (-1306 C/T) and TIMP-2 (-418 G/C) polymorphisms and the risk for acne in a Turkish population. The study was conducted with 85 subjects who presented to the Dermatology Department of Duzce University Hospital. DNA was isolated from 2 ml of peripheral blood taken from each subject, and their genotypes were analyzed with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The CC, CT, and TT genotypes for MMP-2 (-1306 C/T) polymorphism were similar between the patient and control group (24 [55.8%], 17 [39.5%], and 2 [4.7%], respectively, vs. 21 [50%], 18 [42.9%], and 3 [7.1%], respectively). However, the distribution of the GG, GC, and CC genotypes for TIMP-2 (-418 G/C) polymorphism were different between the patient and control group (30 [69.8%], 9 [14.8%] and 4 [9.3%], respectively, vs. 26 [61.9%], 14 [33.3%], and 2 [4.8%], respectively). The results demonstrated that the TIMP-2 (-418 CC) genotype was nearly two times more common in the patient group compared to the control group (p=0.686, OR=1.45). It may be possible that the TIMP-2 (-418 CC) genotype increases the tendency to develop acne vulgaris by disrupting the balance between MMPs and TIMPs. Further investigations are needed to clarify more precisely the relationship between acne and MMP-TIMP genes.

Sirtuins in dermatology: applications for future research and therapeutics

Sirtuins are a family of seven proteins in humans (SIRT1-SIRT7) that are involved in multiple cellular processes relevant to dermatology. The role of sirtuins in other organ systems is established. However, the importance of these proteins in dermatology is less defined. Recently, sirtuins gained international attention because of their role as "longevity proteins" that may extend and enhance human life. Sirtuins function in the cell via histone deacetylase and/or adenosine diphosphate ribosyltransferase enzymatic activity that target histone and non-histone substrates, including transcription regulators, tumor suppressors, structural proteins, DNA repair proteins, cell signaling proteins, transport proteins, and enzymes. Sirtuins are involved in cellular pathways related to skin structure and function, including aging, ultraviolet-induced photoaging, inflammation, epigenetics, cancer, and a variety of cellular functions including cell cycle, DNA repair and proliferation. This review highlights sirtuin-related cellular pathways, therapeutics and pharmacological targets in atopic dermatitis, bullous dermatoses, collagen vascular disorders, psoriasis, systemic lupus erythematosus, hypertrophic and keloid scars, cutaneous infections, and non-melanoma and melanoma skin cancer. Also discussed is the role of sirtuins in the following genodermatoses: ataxia telangiectasia, Cowden's syndrome, dyskeratosis congenita, Rubenstein-Taybi, Werner syndrome, and xeroderma pigmentosum. The pathophysiology of these inherited diseases is not well understood, and sirtuin-related processes represent potential therapeutic targets for diseases lacking suitable alternative treatments. The goal of this review is to bring attention to the dermatology community, physicians, and scientists, the importance of sirtuins in dermatology and provide a foundation and impetus for future discussion, research and pharmacologic discovery.