The emerging principles for acne biogenesis: A dermatological problem of puberty

Development and characterization of a Vaccinium vitis-idaea liposomal gel for the treatment of atopic dermatitis

OBJECTIVE

In this study, a liposomal gel with anti-inflammatory, antibacterial, and antioxidant effects and improving atopic dermatitis (AD) was prepared using Vaccinium vitis-idaea polyphenol as the main active ingredient, which is safe, effective, of stable quality and has anti-inflammatory and antimicrobial effects.

METHODS

The polyphenol extract from Vaccinium vitis-idaea was obtained through ultrasonic extraction and subsequently purified using macroporous resin. A liposome gel incorporating this extract was formulated using poloxamer 188 and poloxamer 407 as the base materials. The gel's physical characteristics, including appearance, vesicle size, and zeta potential, were systematically characterized. Furthermore, its anti-inflammatory, antioxidant, anti-aging, and anti-AD effects were assessed through both ex vivo and in vivo studies.

RESULTS

After process optimization, the yield of Vaccinium vitis-idaea polyphenol was 4.33%; the encapsulation rate of Vaccinium vitis-idaea liposome was 90.45%. The liposome gel prepared by the optimal process had a zeta potential of -33.67 mV, a particle size of 119 nm, a PDI of 0.147, and showed good stability under the conditions of 60 °C, 75% relative humidity, and light intensity of 4500 ± 500 Lux. The results of in vitro studies showed that Vaccinium vitis-idaea polyphenols have antibacterial and antioxidant effects, and the results of in vivo studies showed that the Vaccinium vitis-idaea liposome gel is safe for skin application, effectively reduces dandruff and erythema, reduces the degree of keratinization, reduces the degree of congestion and inflammatory infiltration of local tissues as well as increasing the content of collagen fibers in skin tissues, promotes the restoration of the structural integrity of the skin, and by reducing the inflammatory factors TNF-α, IL-4. By reducing the expression level of inflammatory factors TNF-α, IL-4, IL-13, and MDA, increasing the expression level of SOD, and reducing the diversity of bacterial flora in AD tissues, it can play the role of anti-inflammatory, anti-bacterial, and antioxidant effects and improve the symptoms of AD.

CONCLUSION

The present study demonstrated that the prepared Vaccinium vitis-idaea liposome gel had an ameliorating effect on AD.

Macrophages in acne vulgaris: mediating phagocytosis, inflammation, scar formation, and therapeutic implications

Macrophages serve as a pivotal nexus in the pathogenesis of acne vulgaris, orchestrating both the elimination of Cutibacterium acnes (C. acnes) and lipid metabolic regulation while also possessing the capacity to exacerbate inflammation and induce cutaneous scarring. Additionally, recent investigations underscore the therapeutic potential inherent in macrophage modulation and challenge current anti-inflammatory strategies for acne vulgaris. This review distills contemporary advances, specifically examining the dual roles of macrophages, underlying regulatory frameworks, and emergent therapeutic avenues. Such nuanced insights hold the promise of guiding future explorations into the molecular etiology of acne and the development of more efficacious treatment modalities.

Scientometric analysis of trends in global research on acne treatment

Acne or acne vulgaris is the most common chronic inflammatory disease of the sebaceous follicles.

Objectives

The present study aims to identify the main lines of research in the field of acne treatment using reproducible scientometric methods. In this article, we reviewed the following research trends: facial acne, different antibiotics, retinoids, anti-inflammatory drugs, epidermal growth factor receptor inhibitors therapy, and associated diseases.

Methods

The analysis of publications from the PubMed collection was carried out from 1871 to 2022. All data were analyzed using Microsoft Excel. The evolution of the terminological portrait of the disease is shown.

Results

Trends in the use of various groups of antibiotics, retinoids, anti-inflammatory drugs, and photodynamic therapy for acne treatment have been found. There is a growing interest in clindamycin and doxycycline (polynomial and exponential growth, respectively). The effects of isotretinoin are also being studied more frequently (active linear growth). The publication of studies on spironolactone is increasing (linear growth). There is also a steady interest in the use of epidermal growth factor receptor inhibitors in the recent years. There is active research on acne and polycystic ovary syndrome (exponential growth).

Limitations

Only articles in English were selected. The most frequent terms were considered.

Conclusions

The dynamics of publication activity in the field of acne was considered. The aim of the current scientometric study was to analyze the global trends in acne treatments. The trend analysis made it possible to identify the most explored areas of research, as well as indicate those areas in dermatology in which interest is declining.

Recent advances in understanding inflammatory acne: Deciphering the relationship between Cutibacterium acnes and Th17 inflammatory pathway

Acne vulgaris is a common chronic inflammatory skin disease of the pilosebaceous units. Four factors contribute to acne: hyperseborrhea and dysseborrhea, follicular hyperkeratinisation, skin microbiome dysbiosis and local immuno-inflammation. Recent key studies have highlighted a better understanding of the important role of Cutibacterium acnes (C. acnes) in the development of acne. Three major findings in the last decade include: (1) the ability of C. acnes to self-organize in a biofilm associated with a more virulent activity, (2) the loss of the C. acnes phylotype diversity and (3) the central role of the Th17 pathway in acne inflammation. Indeed, there is a close link between C. acnes and the activation of the Th17 immuno-inflammatory pathway at the initiation of acne development. These mechanisms are directly linked to the loss of C. acnes phylotype diversity during acne, with a predominance of the pro-pathogenic phylotype IA1. This specifically contributes to the induction of the Th17-mediated immuno-inflammatory response involving skin cells, such as keratinocytes, monocytes and sebocytes. These advancements have led to new insights into the underlying mechanisms which can be harnessed to develop novel treatments and diagnostic biomarkers. A major disadvantage of traditional treatment with topical antibiotics is that they induce cutaneous dysbiosis and antimicrobial resistance. Thus, future treatments would no longer aim to 'kill' C. acnes, but to maintain the skin microbiota balance allowing for tissue homeostasis, specifically, the restoration of C. acnes phylotype diversity. Here, we provide an overview of some of the key processes involved in the pathogenesis of acne, with a focus on the prominent role of C. acnes and the Th17-inflammatory pathways involved.

Carbopol-olive oil-based bigel drug delivery system of doxycycline hyclate for the treatment of acne

OBJECTIVE

The objective of this study was to prepare and evaluate the doxycycline hyclate containing bigel for the effective treatment of acne.

METHODS

Bigels are biphasic systems formed by water-based hydrogels and oil-based organogel. Carbopol 940 was used to prepare the hydrogel phase, whereas Span-60 and olive oil for the oleogel phase.

RESULTS

The microstructure of bigel confirmed the oil in water type emulsion formation. The average droplet size of formulations was found 15-50 µm, and a bell-shaped droplet distribution curve, rheological, or viscosity studies suggested that the consistency and stability of bigel decrease with high organogel concentration. Three formulations (F1, F2, and F3) of the different ratios of hydrogel:oleogel (60:40, 70:30, and 80:20) were prepared in which F1 was less stable compared to F2 and F3. The drug content of F2 and F3 was respectively 79.94 and 71.33%. Formulation F2 was found more effective as compared to F3 based on in vitro drug release studies. Bigel also showed better results during in vivo studies at the rabbit ear model, which reduce acne diameter up to 1.10 mm from 4.9 mm while gel reduced it up to 1.20 mm.

Knockdown of H19 Inhibits the Pathogenesis of Acne Vulgaris by Targeting the miR-196a/TLR2/NF-κB Axis

Acne vulgaris (AV) is a chronic inflammatory disease of the pilosebaceous unit, and Propionibacterium acnes (P. acnes) has been implicated in acne inflammation. Numerous studies have shown that non-coding RNAs play important roles in regulating the pathophysiological processes of acne. In addition, the first imprinted long non-coding RNA (lncRNA) identified, H19, plays a critical role in inflammatory disease. However, the expression and role of H19 in AV remain unclear. In this study, we investigated the effects of H19 in keratinocytes and explored the regulatory mechanisms underlying these effects. H19 was upregulated in keratinocytes treated with P. acnes in a concentration-dependent manner. The phosphorylated forms of the nuclear factor (NF)-κB-related proteins IκBα (p-IκBα) and p65 (p-P65) were significantly upregulated after P. acnes treatment. Additionally, secretion of the proinflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8 was upregulated in a concentration-dependent manner. Knockdown of H19 inhibited the expression of p-IκBα and p-P65 as well as the secretion of TNF-α, IL-6, and IL-8 in keratinocytes treated with P. acnes. Moreover, H19 was found to exert its proinflammatory effects by activating NF-κB. H19, which was localized mainly in the cytoplasm of keratinocytes, facilitated Toll-like receptor 2 (TLR2) expression by acting as a miR-196a sponge. H19 thus promoted the activation of NF-κB and the secretion of inflammatory cytokines through the miR-196a/TLR2 axis. These findings provide novel insight into the pathogenesis of AV.

Evaluation of the changes in sebum, moisturization and elasticity in acne vulgaris patients receiving systemic isotretinoin treatment

AIM

The aim of this study was to determine the change in facial skin sebum, hydration and elasticity of acne vulgaris patients after being treated with systemic isotretinoin.

METHOD

Patients who were diagnosed with acne vulgaris and who received systemic isotretinoin treatment for 6 months in Cerrahpaşa Medical Faculty Department of Dermatology between June 2012 and May 2017 were included in this study. The sebum, hydration and elasticity of the skin were measured non-invasively with a device called "Soft Plus Skin Analyses System" before treatment and 6 months after treatment. The relationship between the pre-treatment and post-treatment values were evaluated statistically. 35 adult patients (20 female, 15 male) who were diagnosed with acne vulgaris and who received systemic isotretinoin treatment for 6 months.

RESULTS

The pre-treatment sebum value for both sexes ranged between 5 and 100 and the mean value was calculated as 75.8 ± 28.0. The post-treatment sebum values ranged between 1 and 98 and the mean value was calculated as 48.4 ± 31.8. The difference between the pre-treatment and post-treatment values was statistically significant, p < 0.001. The decline in sebum value after treatment was 36%. The pre-treatment hydration values ranged between 9 and 77.5 and the mean was 34.6 ± 14.6. The post treatment hydration values ranged between 4.8 and 100 and the mean was calculated as 62.4 ± 28.6. The difference between the pre-treatment and post-treatment hydration values were statistically significant, p < 0.001. The post-treatment increase in hydration was 79%. The pre-treatment skin elasticity ranged between 28 and 50; the mean was 40.4 ± 5.5. The post-treatment elasticity values ranged between 20 and 50; and the mean was 37.5 ± 8.2. However, the difference was not statistically significant (p = 0.1).

CONCLUSION

With this study, it was concluded that, systemic isotretion leads to a 36% decline in skin sebum values and a 79% increase in the skin hydration. However, the change in skin elasticity was not statistically significant. Furthermore, the changes in sebum and skin hydration did not lead to a change in skin elasticity.

Rhodomyrtone as a New Natural Antibiotic Isolated from Rhodomyrtus tomentosa Leaf Extract: A Clinical Application in the Management of Acne Vulgaris

Rhodomyrtone, a plant-derived principal compound isolated from Rhodomyrtus tomentosa (Myrtaceae) leaf extract, was assessed as a potential natural alternative for the treatment of acne vulgaris. The clinical efficacy of a 1% liposomal encapsulated rhodomyrtone serum was compared with a marketed 1% clindamycin gel. In a randomized and double-blind controlled clinical trial, 60 volunteers with mild to moderate acne severity were assigned to two groups: rhodomyrtone serum and clindamycin gel. The volunteers were instructed to apply the samples to acne lesions on their faces twice daily. A significant reduction in the total numbers of acne lesions was demonstrated in both treatment groups between week 2 and 8 (p < 0.05). Significant differences in acne numbers compared with the baseline were evidenced at week 2 onwards (p < 0.05). At the end of the clinical trial, the total inflamed acne counts in the 1% rhodomyrtone serum group were significantly reduced by 36.36%, comparable to 34.70% in the clindamycin-treated group (p < 0.05). Furthermore, a commercial prototype was developed, and a clinical assessment of 45 volunteers was performed. After application of the commercial prototype for 1 week, 68.89% and 28.89% of volunteers demonstrated complete and improved inflammatory acne, respectively. All of the subjects presented no signs of irritation or side effects during the treatment. Most of the volunteers (71.11%) indicated that they were very satisfied. Rhodomyrtone serum was demonstrated to be effective and safe for the treatment of inflammatory acne lesions.

Acne vulgaris: role of the immune system

Acne vulgaris is a worldwide condition that has a complex pathophysiology. The knowledge of this pathology is clear in its four classic principles based on the pilosebaceous unit; there exists hyperkeratinization of its duct, increase of sebum production, anaerobic bacterias, and inflammatory response. However, new findings have explained the relationship that occurs inside the acne lesion. The immune system has a key role since it is stimulated by the other participants involved, such as phylotypes of Propionibacterium acnes (P. acnes), antimicrobial peptides (AMPs), sebaceous glands (SGs), matrix metalloproteinases (MMPs), and other immune system pathways.

Nonprescription acne vulgaris treatments: Their role in our treatment armamentarium-An international panel discussion

BACKGROUND

Acne vulgaris (acne), a common inflammatory skin disorder, has its peak incidence between 14 and 19 years of age, with girls frequently developing acne earlier than boys. Over recent years, persistent acne is becoming more prevalent in adult women.

OBJECTIVES

This review and panel discussion addresses challenges in acne management, particularly in adult women. The role which nonprescription acne treatment can play is explored when used as monotherapy or as an adjunctive treatment for acne of all severity.

METHODS

The best available evidence on nonprescription acne treatment was coupled with the opinion of an international expert panel of dermatologists to adopt statements and recommendations discussed in this review.

RESULTS

All severity of acne has a significant burden on patients. Addressing environmental factors that are important for the individual with acne may help to educate, prevent, effectively manage, and maintain acne, as per the panel. They agreed that the adult female acne population has unique needs because of their aging skin and social environment. Nonprescription acne treatment products may help to balance the efficacy and tolerability of prescription acne treatment. Currently, there are no specific guidelines for how to use nonprescription acne treatment products in these patients.

CONCLUSION

The panel agreed that guidelines including nonprescription acne treatment either as monotherapy for mild acne or in combination with prescription treatments for more severe acne would address a significant unmet need.

The role of the skin microbiota in acne pathophysiology

BACKGROUND

The role of skin microbiota in acne remains to be fully elucidated. Initial culture-based investigations were hampered by growth rate and selective media bias. Even with less biased genomic methods, sampling, lysis and methodology, the task of describing acne pathophysiology remains challenging. Acne occurs in sites dominated by Cutibacterium acnes (formerly Propionibacterium acnes) and Malassezia species, both of which can function either as commensal or pathogen.

OBJECTIVES

This article aims to review the current state of the art of the microbiome and acne.

METHODS

The literature regarding the microbiome and acne was reviewed.

RESULTS

It remains unclear whether there is a quantitative difference in microbial community distribution, making it challenging to understand any community shift from commensal to pathogenic nature. It is plausible that acne involves (i) change in the distribution of species/strains, (ii) stable distribution with pathogenic alteration in response to internal (intermicrobe) or external stimuli (host physiology or environmental) or (iii) a combination of these factors.

CONCLUSIONS

Understanding physiological changes in bacterial species and strains will be required to define their specific roles, and identify any potential intervention points, in acne pathogenesis and treatment. It will also be necessary to determine whether any fungal species are involved, and establish whether they play a significant role. Further investigation using robust, modern analytic tools in longitudinal studies with a large number of participants, may make it possible to determine whether the microbiota plays a causal role, is primarily involved in exacerbation, or is merely a bystander. It is likely that the final outcome will show that acne is the result of complex microbe-microbe and community-host interplay.