Review of the innate immune response in acne vulgaris: activation of Toll-like receptor 2 in acne triggers inflammatory cytokine responses

Cath-HG exhibits anti-acne activities via multiple mechanisms

The overgrowth of Propionibacterium acnes and the subsequent inflammation possess critical roles during acne vulgaris development. Cath-HG, an antimicrobial peptide previously characterized for its antimicrobial, anti-inflammatory, human protease-regulating, LPS-binding, and platelet glycoprotein VI (GPVI) inhibitory properties, has not been studied in the context of acne vulgaris. Here, Cath-HG was found to show strong anti-bacterial activities against P. acnes by promoting agglutination of bacteria, inhibition of biofilm formation, and disruption of the bacterial membrane. It also suppressed reactive oxygen species (ROS) and sebum production induced by P. acnes in HaCaT cells and inhibited the enzymatic activity of lipases and hyaluronidase. Moreover, Cath-HG also bound to lipoteichoic acid (LTA) and significantly attenuated the production of inflammatory factors through Toll-like receptor 2 (TLR2) in RAW264.7 macrophages. Consistently, Cath-HG exhibited antimicrobial effects and exerted anti-inflammatory activity by suppressing the activation of the mitogen-activated protein kinase (MAPK) signaling pathway in a P. acnes-induced mouse model. Consequently, Cath-HG could be a promising candidate for treatment of acne vulgaris.

Integrated analysis of microbiome and metabolome reveals signatures in PDAC tumorigenesis and prognosis

Pancreatic cancer, predominantly pancreatic ductal adenocarcinoma (PDAC), is one of the most malignant tumors of the digestive system. Emerging evidence suggests the involvement of the microbiome and metabolic substances in the development of PDAC, yet the results remain contradictory. This study aims to identify the alterations and relationships in intratumoral microbiome and metabolites in PDAC. We collected matched tumor and normal adjacent tissue (NAT) samples from 105 PDAC patients and performed a 6-year follow-up. 2bRAD-M sequencing, untargeted liquid chromatography-tandem mass spectrometry, and untargeted gas chromatography-mass spectrometry were performed. Compared with NATs, microbial α-diversity decreased in PDAC tumors. The relative abundance of Staphylococcus aureus, Cutibacterium acnes, and Cutibacterium granulosum was higher in PDAC tumor after adjusting for confounding factors body mass index and M stage, and the presence of Ralstonia pickettii_B was found associated with a worse overall survival. Metabolomic analysis revealed distinctive differences in composition between PDAC and NAT, with 553 discriminative metabolites identified. Differential metabolites were revealed to originate from the microbiota and showed significant interactions with shifted bacterial species through KO (KEGG Orthology) genes. These findings suggest that the PDAC microenvironment harbors unique microbial-derived enzymatic reactions, potentially influencing the occurrence and development of PDAC by modulating the levels of glycerol-3-phosphate, succinate, carbonate, and beta-alanine.

IMPORTANCE

We conducted a large sample-size pancreatic adenocarcinoma microbiome study using a novel microbiome sequencing method and two metabolomic assays. Two significant outcomes of our analysis are: (i) commensal opportunistic pathogens Staphylococcus aureus, Cutibacterium acnes, and Cutibacterium granulosum were enriched in pancreatic ductal adenocarcinoma (PDAC) tumors compared with normal adjacent tissues, and (ii) worse overall survival was found related to the presence of Ralstonia pickettii_B. Microbial species affect the tumorigenesis, metastasis, and prognosis of PDAC via unique microbe-enzyme-metabolite interaction. Thus, our study highlights the need for further investigation of the potential associations between pancreatic microbiota-derived omics signatures, which may drive the clinical transformation of microbiome-derived strategies toward therapy-targeted bacteria.

Biofilm of Cutibacterium acnes: a target of different active substances

BACKGROUND

Acne vulgaris is a chronic inflammatory dermatosis. Cutibacterium acnes plays a crucial role in the acne pathophysiology. Recent works present evidence of C. acnes growing as a biofilm in cutaneous follicles. This development is currently considered one of the leading causes of C. acnes in vivo persistence and resistance to antimicrobials used to treat acne.

OBJECTIVE

Our objective was to evaluate the effects of various active compounds (clindamycin, erythromycin, doxycycline, and myrtle extract) on eight distinct, well-characterized strains of C. acnes following their growth in biofilm mode.

METHODS/RESULTS

Cutibacterium acnes isolates from phylotypes IA1 and IA2 produce more biofilm than other phylotypes. No antibiotic effect was observed either during the curative test or preventive test. Myrtle extract at 0.01% (w/v) showed significant efficacy on the biofilm for C. acnes strains (curative assays). Furthermore, it appear that myrtle extract and doxycycline together reduce the overall biomass of the biofilm. A significant dose-dependent effect was observed during the preventive test, greater than the one observed under curative conditions, with an important loss of activity of the myrtle extract observed from 0.001% (w/v) concentration onwards. Transmission electron microscopy showed that bacteria treated with myrtle extract grew biofilms much less frequently than untreated bacteria. Additionally, when the quantity of myrtle extract grew, the overall number of bacteria dropped, indicating an additional antibacterial action.

CONCLUSION

These findings support the hypothesis that the different C. acnes phylotypes have various aptitudes in forming biofilms. They also suggest that myrtle extract is a promising alternative as an anti-biofilm and antibacterial agent in fighting diseases caused by planktonic and biofilm C. acnes.

Evaluation of in vitro Skin Permeation of Clascoterone From Clascoterone Topical Cream, 1% (w/w)

Winlevi® (clascoterone) topical cream (1%, w/w) was approved by the U.S. FDA for the treatment of acne vulgaris in patients 12 years of age and older. The active ingredient, clascoterone, is not stable in physiological solutions and can hydrolyze to cortexolone at body temperature. Instability of clascoterone poses a significant challenge in accurately assessing the rate and extent of clascoterone permeation in vitro. Therefore, the purpose of this study was to develop an in vitro skin permeation test (IVPT) method, and a robust analytical method, that can minimize hydrolyzation of clascoterone during the study for quantification of clascoterone. Two IVPT methods, using either vertical diffusion cells or flow-through cells, were developed and compared to evaluate in vitro permeation of clascoterone from Winlevi. A liquid chromatography with tandem mass spectrometry (LC-MS/MS) method was developed to monitor the level of clascoterone and cortexolone in the IVPT samples. The analytical method features a 2-min high-throughput analysis with good linearity, selectivity, and showed a lower limit of quantitation (LLOQ) of 0.5 ng/mL for both clascoterone and cortexolone. The in vitro skin permeation of clascoterone and cortexolone was observed as early as 2 h in both IVPT methods. A substantive amount of clascoterone was found to hydrolyze to cortexolone when using the vertical static diffusion cells with aliquot sampling. Conversely, degradation of clascoterone was significantly minimized when using the flow-through diffusion cells with fractional sampling. The data enhanced our understanding of in vitro permeation of clascoterone following topical application of the Winlevi topical cream, 1% and underscores the importance of IVPT method development and optimization during product development.

Minor Cannabinoids as Inhibitors of Skin Inflammation: Chemical Synthesis and Biological Evaluation

Despite millennia of therapeutic plant use, deliberate exploitation of Cannabis's diverse biomedical potential has only recently gained attention. Bioactivity studies focus mainly on cannabidiol (CBD) and tetrahydrocannabinol (THC) with limited information about the broader cannabinome's "minor phytocannabinoids". In this context, our research targeted the synthesis of minor cannabinoids containing a lateral chain with 3 or 4 carbon atoms, focusing on cannabigerol (CBG) and cannabichromene (CBC) analogues. Using known and innovative strategies, we achieved the synthesis of 11 C3 and C4 analogues, five of which were inhibitors of skin inflammation, with the CBG-C4 ester derivative emerging as the most potent compound.

Exploring Acne Treatments: From Pathophysiological Mechanisms to Emerging Therapies

Acne vulgaris is a common dermatological condition that can present across different ages but predominantly affects adolescents and young adults. Characterized by various lesion types, the pathogenesis of acne is complex, involving genetic, hormonal, microbial, and inflammatory factors. This review comprehensively addresses current and emerging acne management strategies, emphasizing both topical and systemic treatments, procedural therapies, and dietary modifications. Key topical agents include retinoids, benzoyl peroxide, antibiotics, and other specialized compounds. Systemic options like antibiotics, hormonal therapies, and retinoids offer significant therapeutic benefits, particularly for moderate to severe cases. Procedural treatments such as laser devices, photodynamic therapy, chemical peels, and intralesional injections present viable alternatives for reducing acne symptoms and scarring. Emerging therapies focus on novel biologics, bacteriophages, probiotics, and peptides, providing promising future options. This review underscores the importance of personalized approaches to treatment due to the multifaceted nature of acne, highlighting the potential of innovative therapies for improving patient outcomes.

Investigation into the Anti-Acne Effects of Castanea sativa Mill Leaf and Its Pure Ellagitannin Castalagin in HaCaT Cells Infected with Cutibacterium acnes

Acne vulgaris is a prevalent skin disorder affecting many young individuals, marked by keratinization, inflammation, seborrhea, and colonization by Cutibacterium acnes (C. acnes). Ellagitannins, known for their antibacterial and anti-inflammatory properties, have not been widely studied for their anti-acne effects. Chestnut (Castanea sativa Mill., C. sativa), a rich ellagitannin source, including castalagin whose acne-related bioactivity was previously unexplored, was investigated in this study. The research assessed the effect of C. sativa leaf extract and castalagin on human keratinocytes (HaCaT) infected with C. acnes, finding that both inhibited IL-8 and IL-6 release at concentrations below 25 μg/mL. The action mechanism was linked to NF-κB inhibition, without AP-1 involvement. Furthermore, the extract displayed anti-biofilm properties and reduced CK-10 expression, indicating a potential role in mitigating inflammation, bacterial colonization, and keratosis. Castalagin's bioactivity mirrored the extract's effects, notably in IL-8 inhibition, NF-κB inhibition, and biofilm formation at low μM levels. Other polyphenols, such as flavonol glycosides identified via LC-MS, might also contribute to the extract's biological activities. This study is the first to explore ellagitannins' potential in treating acne, offering insights for developing chestnut-based anti-acne treatments pending future in vivo studies.

Association of different cell types and inflammation in early acne vulgaris

Acne vulgaris, one of the most common skin diseases, is a chronic cutaneous inflammation of the upper pilosebaceous unit (PSU) with complex pathogenesis. Inflammation plays a central role in the pathogenesis of acne vulgaris. During the inflammatory process, the innate and adaptive immune systems are coordinately activated to induce immune responses. Understanding the infiltration and cytokine secretion of differential cells in acne lesions, especially in the early stages of inflammation, will provide an insight into the pathogenesis of acne. The purpose of this review is to synthesize the association of different cell types with inflammation in early acne vulgaris and provide a comprehensive understanding of skin inflammation and immune responses.

Unraveling the pharmaceutical and clinical relevance of the influence of syringic acid loaded linoleic acid transferosomes on acne

Natural medicines are promising platforms for competent topical treatment modalities benefiting the cosmetic implementation and proffering solutions to the current remedies. Therefore, the objective of this study was to formulate syringic acid (SA), well-known for its multilateral anti-inflammatory, antimicrobial and antioxidant potentials, in newly developed linoleic acid (LA) transferosomes as an anti-acne nano-form remedy. Herein, LA was incorporated in transferosomes owing to its antimicrobial effect and dermal penetrability. Comprehensive appraisal through physicochemical, antioxidant and dermal deposition investigations was conducted. Clinical assessment was also performed in acne patients and compared with the marketed product (Adapalene® gel). The relevant investigations of the optimum formula indicated stable vesicles with a small-sized diameter (147.46 nm), surface charge (-26.86 mV), spherical architecture, reasonable entrapment (76.63%), considerable antioxidant activity (IC50 = 11.1 µg/mL) and remarkable skin deposition (78.72%).More importantly, LA based transferosomes enclosing SA exhibited inflammation lessening in acne sufferers as manifested by greater reduction in the total count of the acne lesions reaching 79.5% in contrast to Adapalene® gel with only 18.7% reduction in acne lesions. Interestingly, no irritation and erythema were reported for the proposed transferosomes. Inclusively, the cosmetic formulation practice could reap benefits of the development of such vesicles.

A Randomized Split-Face Study of Photodynamic Therapy With St. John's Wort and Indole-3-Acetic Acid for the Treatment of Acne

BACKGROUND

St. John's wort (SJW) contains hypericin, a powerful photosensitizer with antimicrobial and anti-inflammatory activities.

OBJECTIVE

To compare the efficacy and safety of SJW-photodynamic therapy (PDT) with that of indole-3-acetic acid (IAA)-PDT for the treatment of acne and investigate the skin rejuvenating effects of SJW-PDT.

MATERIALS AND METHODS

In vitro experiments were conducted to examine the generation of reactive oxygen species and the antimicrobial effects of SJW-PDT. In the prospective, double-blind, split-face, randomized study, 31 patients with facial acne were treated with SJW or IAA with simultaneous illumination of red light and green light.

RESULTS

SJW produces free radicals with visible light irradiation, and the growth of Cutibacterium acnes and Staphylococcus aureus is significantly suppressed. One week after the last treatment, the acne lesion counts were significantly decreased in both groups (56.5% reduction in SJW, p < .001 vs 57.0% in IAA, p < .001). Significant reductions in sebum secretion, erythema index, roughness, and wrinkles were observed in both groups after the treatment. No side effects were observed.

CONCLUSION

SJW-PDT is a simple, safe, and effective treatment option for acne that is also beneficial for skin rejuvenation.

Skin dysbiosis and Cutibacterium acnes biofilm in inflammatory acne lesions of adolescents

Acne vulgaris is a common inflammatory disorder affecting more than 80% of young adolescents. Cutibacterium acnes plays a role in the pathogenesis of acne lesions, although the mechanisms are poorly understood. The study aimed to explore the microbiome at different skin sites in adolescent acne and the role of biofilm production in promoting the growth and persistence of C. acnes isolates. Microbiota analysis showed a significantly lower alpha diversity in inflammatory lesions (LA) than in non-inflammatory (NI) lesions of acne patients and healthy subjects (HS). Differences at the species level were driven by the overabundance of C. acnes on LA than NI and HS. The phylotype IA1 was more represented in the skin of acne patients than in HS. Genes involved in lipids transport and metabolism, as well as potential virulence factors associated with host-tissue colonization, were detected in all IA1 strains independently from the site of isolation. Additionally, the IA1 isolates were more efficient in early adhesion and biomass production than other phylotypes showing a significant increase in antibiotic tolerance. Overall, our data indicate that the site-specific dysbiosis in LA and colonization by virulent and highly tolerant C. acnes phylotypes may contribute to acne development in a part of the population, despite the universal carriage of the microorganism. Moreover, new antimicrobial agents, specifically targeting biofilm-forming C. acnes, may represent potential treatments to modulate the skin microbiota in acne.

Sulforaphene Attenuates Cutibacterium acnes-Induced Inflammation

Acne is a chronic inflammatory disease of the sebaceous gland attached to the hair follicles. Cutibacterium acnes is a major cause of inflammation caused by acne. It is well known that C. acnes secretes a lipolytic enzyme to break down lipids in sebum, and free fatty acids produced at this time accelerate the inflammatory reaction. There are several drugs used to treat acne; however, each one has various side effects. According to previous studies, sulforaphene (SFEN) has several functions associated with lipid metabolism, brain function, and antibacterial and anti-inflammatory activities. In this study, we examined the effects of SFEN on bacterial growth and inflammatory cytokine production induced by C. acnes. The results revealed that SFEN reduced the growth of C. acnes and inhibited proinflammatory cytokines in C. acnes-treated HaCaT keratinocytes through inhibiting NF-κB-related pathways. In addition, SFEN regulated the expression level of IL-1α, a representative pro-inflammatory cytokine expressed in co-cultured HaCaT keratinocytes and THP-1 monocytes induced by C. acnes. In conclusion, SFEN showed antibacterial activity against C. acnes and controlled the inflammatory response on keratinocytes and monocytes. This finding means that SFEN has potential as both a cosmetic material for acne prevention and a pharmaceutical material for acne treatment.

Active compounds in kepok banana peel as anti-inflammatory in acne vulgaris: Review article

Background

Acne vulgaris (AV) is a chronic inflammatory skin condition affecting the pilosebaceous units characterized by recurrent comedones, erythematous papules and pustules. The disease is benign however may produce scarring, erythema, and hyperpigmentation resulting in physical and psychological problems. Conventional therapy may reduce the symptoms of AV nevertheless, has a possibility of resistance, unwanted side effects, and has high cost. Thus, utilizing natural remedies may be a useful.

Methods

The data in this study were collect by search the keyword combinations of medical subject heading (mesh) of "inhibition", "antimicrobial", "banana peel", "acne vulgaris" and "antiinflammation" and relevant reference lists were manually searched in PubMed, EMBRASE and Scopus database. All relevant articles in data base above were included and narratively discussed in this review article.

Objective

To discuss the bioactive potential of banana peel as an inflammatory modulator in acne vulgaris.

Results

Banana peel contains many bioactive compounds, particularly phenolic and non-phenolic antioxidants (ascorbic acid, carotene, and cyanidin) which are pivotal in removing inflammatory products by inhibiting reactive oxygen species (ROS), protecting protease inhibitors from oxidative damage, and preventing fibroblasts degradation. Banana peel also contains anti-inflammatory agents such as trigonelline which inhibits bacterial enzymes and nucleic acid synthesis; isovanillic acid which suppresses TNF-α production; and ferulic acid which inhibits the production of proinflammatory signaling and cytokines.

Conclusion

Banana peel contains many bioactive compounds which demonstrate anti-inflammatory properties through several processes of the inflammatory pathway. However further research is needed to confirm this finding.

Cannabidiol Inhibits Inflammation Induced by Cutibacterium acnes-Derived Extracellular Vesicles via Activation of CB2 Receptor in Keratinocytes

Background

Acne is a common inflammatory skin disease, while cannabidiol (CBD) is a representative non-psychoactive phytocannabinoid which has been proved to exert universal anti-inflammatory properties. This study aimed to explore the effect of CBD on acne inflammation induced by Cutibacterium acnes-derived extracellular vesicles (CEVs) in keratinocytes and reveal the underlying mechanisms.

Methods

Normal human epidermal keratinocytes (NHEKs) were stimulated by CEVs in the presence of CBD or vehicle. Interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α levels were examined by RT-PCR and ELISA. The expression of cannabinoid type-2 (CB2) receptor and transient receptor potential vanilloid type-1 (TRPV1) was detected by Western blotting. TNF-α levels in the presence of CB2 receptor antagonist (AM630) or TRPV1 antagonist (Capsazepine) were detected by RT-PCR. The activation of MAPK and NF-κB signaling pathways and the nuclear translocation of NF-κB p65 upon CBD treatment were analyzed by Western blotting and immunofluorescence assay, respectively.

Results

The expression of inflammatory cytokines (IL-6, IL-8 and TNF-α) in CEVs-stimulated NHEKs was suppressed by CBD. CB2 receptor expression was upregulated by CBD, whereas CEVs-promoted TRPV1 expression was downregulated by CBD. AM630 reversed TNF-α levels inhibited by CBD. Capsazepine exerted an inhibitory effect on CEVs-induced inflammation and had synergistic effect with CBD. The phosphorylation of ERK1/2 and NF-κB p65 and nuclear translocation of NF-κB p65 were induced by CEVs but reduced by CBD.

Conclusion

The results indicated that CBD could inhibit inflammation induced by CEVs in NHEKs, which was mediated by activation of CB2 receptor and enhanced by the TRPV1 antagonist, through inactivation of the MAPK and NF-κB signaling pathways. CBD might be a potential novel strategy for acne treatment in the future.

Anti-Inflammatory and Anti-Acne Effects of Hamamelis virginiana Bark in Human Keratinocytes

Cutibacterium acnes (C. acnes) is recognized as one of the main triggers of the cutaneous inflammatory response in acne vulgaris, a chronic skin disorder with a multifactorial origin. Witch hazel (Hamamelis virginiana L.) is a plant widely used for skin inflammatory conditions, with some preliminary anti-inflammatory evidence on the skin, but lacking data on acne conditions. This study aimed to evaluate the effect of a glycolic extract from Hamamelis virginiana bark (HVE) versus C. acnes-induced inflammation in human keratinocytes (HaCaT). Phytochemical investigations of HVE identified hamamelitannin (HT) and proanthocyanidins as the most abundant compounds (respectively, 0.29% and 0.30% w/w_extract). HVE inhibited C. acnes-induced IL-6 release (IC₅₀: 136.90 μg/mL), by partially impairing NF-κB activation; however, no antibacterial or antibiofilm activities were found. In addition, HVE showed greater anti-inflammatory activity when TNF-α was used as a proinflammatory stimulus (IC₅₀ of 38.93 μg/mL for IL-8 release), partially acting by antioxidant mechanisms, as shown for VEGF inhibition. The effects of HVE are primarily based on the proanthocyanidin content, as HT was found inactive on all the parameters tested. These results suggest further investigations of HVE in other inflammatory-based skin diseases.

Explore the Anti-Acne Mechanism of Licorice Flavonoids Based on Metabonomics and Microbiome

Acne vulgaris is one of the most common inflammatory dermatoses in dermatological practice and can affect any gender or ethnic group. Although in previous studies, we had found that licorice flavonoids (LCF) play an anti-acne role by inhibiting PI3K-Akt signaling pathways and mitochondrial activity, the mechanism of LCF regulating skin metabolism, serum metabolism and skin microbes is still unclear. Here, we performed a full spectrum analysis of metabolites in the skin and serum using UHPLC-Triple TOF-MS. The results showed that LCF could treat acne by regulating the metabolic balance of amino acids, lipids and fatty acids in serum and skin. Similarly, we performed Illumina Hiseq sequencing of DNA from the skin microbes using 16S ribosomal DNA identification techniques. The results showed that LCF could treat acne by regulating the skin microbes to interfere with acne and make the microecology close to the normal skin state of rats. In summary, this study confirmed the anti-acne mechanism of LCF, namely by regulating metabolic balance and microbial balance. Therefore, this discovery will provide theoretical guidance for the preparation development and clinical application of the drug.

Micro-Current Stimulation Suppresses Inflammatory Responses in Peptidoglycan-Treated Raw 264.7 Macrophages and Propionibacterium acnes-Induced Skin Inflammation via TLR2/NF-κB Signaling Pathway

Acne is a common inflammatory disorder of the human skin and a multifactorial disease caused by the sebaceous gland and Propionibacterium acnes (P. acnes). This study aimed to evaluate the anti-inflammatory effect of micro-current stimulation (MC) on peptidoglycan (PGN)-treated raw 264.7 macrophages and P. acnes-induced skin inflammation. To specify the intensity with anti-inflammatory effects, nitric oxide (NO) production was compared according to various levels of MC. As the lowest NO production was shown at an intensity of 50 μA, subsequent experiments used this intensity. The changes of expression of the proteins related to TLR2/NF-κB signaling were examined by immunoblotting. Also, immunofluorescence analysis was performed for observing NF-κB p65 localization. All of the expression levels of proteins regarding TLR2/NF-κB signaling were decreased by the application of MC. Moreover, the application of MC to PGN-treated raw 264.7 cells showed a significant decrease in the amount of nuclear p65-protein. In the case of animal models with P. acnes-induced skin inflammation, various pro-inflammatory cytokines and mediators significantly decreased in MC-applied mice. In particular, the concentration of IL-1β in serum decreased, and the area of acne lesions, decreased from the histological analysis. We suggest for the first time that MC can be a novel treatment for acne.

Antimicrobial production by perifollicular dermal preadipocytes is essential to the pathophysiology of acne

Innate immune defense against deep tissue infection by Staphylococcus aureus is orchestrated by fibroblasts that become antimicrobial when triggered to differentiate into adipocytes. However, the role of this process in noninfectious human diseases is unknown. To investigate the potential role of adipogenesis by dermal fibroblasts in acne, a disorder triggered by Cutibacterium acnes, single-cell RNA sequencing was performed on human acne lesions and mouse skin challenged by C. acnes. A transcriptome consistent with adipogenesis was observed within specific fibroblast subsets from human acne and mouse skin lesions infected with C. acnes. Perifollicular dermal preadipocytes in human acne and mouse skin lesions showed colocalization of PREF1, an early marker of adipogenesis, and cathelicidin (Camp), an antimicrobial peptide. This capacity of C. acnes to specifically trigger production of cathelicidin in preadipocytes was dependent on TLR2. Treatment of wild-type mice with retinoic acid (RA) suppressed the capacity of C. acnes to form acne-like lesions, inhibited adipogenesis, and enhanced cathelicidin expression in preadipocytes, but lesions were unresponsive in Camp^-/- mice, despite the anti-adipogenic action of RA. Analysis of inflamed skin of acne patients after retinoid treatment also showed enhanced induction of cathelicidin, a previously unknown beneficial effect of retinoids in difficult-to-treat acne. Overall, these data provide evidence that adipogenic fibroblasts are a critical component of the pathogenesis of acne and represent a potential target for therapy.

The Protective Effects of Cath-MH With Anti-Propionibacterium Acnes and Anti-Inflammation Functions on Acne Vulgaris

Acne vulgaris is a common adolescent skin condition which is mainly caused by Propionibacterium acnes overcolonization and subsequent inflammation. Our previous studies have demonstrated that Cath-MH, an antimicrobial peptide from the skin of the frog Microhyla heymonsivogt, possesses potential antimicrobial, LPS-binding, and anti-septicemic properties. However, its protective effects and potential mechanisms against acne vulgaris are still unclear. In the present study, its anti-P. acnes effects were measured by two-fold broth dilution method, agglutination assay, scanning electron microscopy and confocal laser scanning microscopy experiments. Its treatment potential for acne vulgaris was further evaluated in mice ear inoculated by P. acnes. In addition, the binding ability between Cath-MH and LTA was measured by the Circular Dichroism and antibacterial assay. Moreover, the anti-inflammatory efficiency of Cath-MH was evaluated in LTA- and LPS-induced RAW 264.7 macrophage cells. Cath-MH was found to kill P. acnes with a MIC value of about 1.56 μM by membrane disruption mechanism. It also exhibited agglutination activity against P. acnes. Cath-MH was able to bind LTA as well as LPS, inhibit LTA/LPS-stimulated TLR2/4 expression, and subsequently decreased the inflammatory response in RAW 264.7 cells. As expected, Cath-MH alleviated the formation of edema and the infiltration of inflammatory cells in acne mouse model with concurrent suppression of P. acnes growth and inflammatory cytokines expression in vivo. The potent P. acnes inhibition activity combined with powerful anti-inflammatory effect of Cath-MH indicates its potential as a novel therapeutic option for acne vulgaris.

Insights into the mechanism of Cymbopogan martinii essential oil in topical therapy of acne vulgaris

Aim: The present study investigated the essential oil of Cymbopogan martinii (palmarosa oil; PRO) as a potential topical therapy in acne vulgaris. Materials & methods: GC-MS profiling and biocompatibility studies of PRO were undertaken. The antimicrobial potential was assessed against Cutibacterium acnes. anti-inflammatory, antityrosinase activity and lipid peroxidation were also evaluated. Results: Geraniol was identified as the major phytoconstituent, and the oil was found to be safe for topical application. The minimum inhibitory concentration and minimum bactericidal concentration values were noted as 16 μl/ml. PRO reduced the cytokine levels of TNF-α, IL-12 and IL-8 and inhibited tyrosinase. A low concentration of the oil (up to 0.5 μl/ml) produced malondialdehyde levels equivalent to that of untreated cells. Conclusion: PRO may prove useful as a natural topical agent in the management of acne.

What the Pediatric and Adolescent Gynecology Clinician Needs to Know about Acne

Acne vulgaris is a common skin condition encountered in specialties outside of dermatology, including obstetrics and gynecology. The pathophysiology of acne is complex and includes disruption of the cutaneous microbiome, abnormal keratinization, inflammation, and hormonal influences. Various topical and systemic treatment modalities target each component of acne pathophysiology. Clinically, acne can be broken down into noninflammatory, inflammatory, or mixed subtypes. The age of the patient at presentation and signs and symptoms of hormonal imbalance might prompt workup for underlying disorders. The severity as well as type of acne dictates the type of treatment.

The Clinical Relevance of the Microbiome in Hidradenitis Suppurativa: A Systematic Review

Hidradenitis suppurativa is a chronic disease of the pilosebaceous unit. The name of the condition is a testament to the presumed relationship between the disease and the microbiome. The pathophysiology of hidradenitis suppurativa is, however, complex and believed to be the product of a multifactorial interplay between the interfollicular epithelium, pilosebaceous unit, microbiome, as well as genetic and environmental factors. In this review we assimilate the existing literature regarding the role played by the human microbiome in HS in various contexts of the disease, including the pathophysiologic, therapeutic, and potentially, diagnostic as well prognostic. In conclusion, the role played by the microbiome in HS is extensive and relevant and can have bench-to-bedside applications.

Surface-Modified Multifunctional Thymol-Loaded Biodegradable Nanoparticles for Topical Acne Treatment

The present work is focused on the development of novel surface-functionalized poly(lactic-co-glycolic acid) nanoparticles loaded with thymol (TH-NPs) for topical administration enhancing thymol anti-inflammatory, antioxidant and wound healing activities against acne. TH-NPs were prepared by solvent evaporation method using different surface functionalization strategies and obtaining suitable physicochemical parameters and a good short-term stability at 4 °C. Moreover, TH-NPs skin penetration and antioxidant activity were assessed in ex vivo pig skin models. Skin penetration of TH-NPs followed the follicular route, independently of the surface charge and they were able to enhance antioxidant capacity. Furthermore, antimicrobial activity against Cutibacterium acnes was evaluated in vitro by the suspension test showing improved antibacterial performance. Using human keratinocyte cells (HaCat), cytotoxicity, cellular uptake, antioxidant, anti-inflammatory and wound healing activities were studied. TH-NPs were non-toxic and efficiently internalized inside the cells. In addition, TH-NPs displayed significant anti-inflammatory, antioxidant and wound healing activities, which were highly influenced by TH-NPs surface modifications. Moreover, a synergic activity between TH-NPs and their surface functionalization was demonstrated. To conclude, surface-modified TH-NPs had proven to be suitable to be used as anti-inflammatory, antioxidant and wound healing agents, constituting a promising therapy for treating acne infection and associated inflammation.

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.

Novel mechanisms of microbial crosstalk with skin innate immunity

Skin is an organ with a dynamic ecosystem that harbours pathogenic and commensal microbes, which constantly communicate amongst each other and with the host immune system. Evolutionarily, skin and its microbiota have evolved to remain in homeostasis. However, frequently this homeostatic relationship is disturbed by a variety of factors such as environmental stress, diet, genetic mutations, and the microbiome itself. Commensal microbes also play a major role in the maintenance of microbial homeostasis. In addition to their ability to limit pathogens, many skin commensals such as Staphylococcus epidermidis and Cutibacterium acnes have recently been implicated in disease pathogenesis either by directly modulating the host immune components or by supporting the expansion of other pathogenic microbes. Likewise, opportunistic skin pathogens such as Staphylococcus aureus and Staphylococcus lugdunensis are able to breach the skin and cause disease. Though much has been established about the microbiota's function in skin immunity, we are in a time where newer mechanistic insights rapidly redefine our understanding of the host/microbial interface in the skin. In this review, we provide a concise summary of recent advances in our understanding of the interplay between host defense strategies and the skin microbiota.

Updated Treatment for Acne: Targeted Therapy Based on Pathogenesis

Previous approaches to acne management have focused on the four main factors implicated in acne, namely, androgen-mediated sebogenesis (considered integral to acne), hyperkeratinization, colonization with Cutibacterium acnes, and inflammation related to both innate and adaptive mechanisms. Recent advances have facilitated potential novel approaches to acne management, as the pathophysiology and the immunological aspects related to acne and wound healing have evolved. Particular targets that have been shown to be closely involved in acne pathophysiology and wound healing include interleukin (IL)-1β, IL-17, IL-23, and tumor necrosis factor alpha (TNFα). Biological antibodies targeting IL-1β, IL-17, IL-23, and TNFα could provide novel approaches for treating severe acne and related disorders. Acne is primarily a disease associated with sebogenesis. Monosaturated free acids are important components. Insulin growth factor 1 (IGF-1) promotes the proliferation and differentiation of sebocytes and IL-1β. Research into the microbiome may also provide insights into potential future therapeutic options for acne. Scars, both atrophic and hypertrophic, are common sequelae to acne. Risk factors associated with the development of acne scars include genetic, systemic, local, and lifestyle factors. Pro-inflammatory cytokines have been shown to play a crucial role in the development of acne-induced hypertrophic scars. Treatment for extensive inflammatory keloid scarring is limited. Surgery and postoperative radiotherapy are two possible options. Transforming growth factor-β (TGFβ), IL-6, matrix metalloproteinase (MMP), IGF-1, and B cells are found in keloid or hypertrophic scar tissues. Biological antibodies targeting these cytokines may be a potential strategy for the prevention and treatment of this type of scar in the future. Future treatment for acne should embrace approaches that target the main etiological factors of acne. In particular, specific emphasis on aggressive treatment in the acute inflammatory phase to reduce the likelihood of scarring and other clinical sequelae, such as pigmentary changes would be highly desirable. Treatment for established acne-induced sequelae should also be considered.

Electricity-producing Staphylococcus epidermidis counteracts Cutibacterium acnes

Staphylococcus epidermidis (S. epidermidis) ATCC 12228 was incubated with 2% polyethylene glycol (PEG)-8 Laurate to yield electricity which was measured by a voltage difference between electrodes. Production of electron was validated by a Ferrozine assay. The anti-Cutibacterium acnes (C. acnes) activity of electrogenic S. epidermidis was assessed in vitro and in vivo. The voltage change (~ 4.4 mV) reached a peak 60 min after pipetting S. epidermidis plus 2% PEG-8 Laurate onto anodes. The electricity produced by S. epidermidis caused significant growth attenuation and cell lysis of C. acnes. Intradermal injection of C. acnes and S. epidermidis plus PEG-8 Laurate into the mouse ear considerably suppressed the growth of C. acnes. This suppressive effect was noticeably reversed when cyclophilin A of S. epidermidis was inhibited, indicating the essential role of cyclophilin A in electricity production of S. epidermidis against C. acnes. In summary, we demonstrate for the first time that skin S. epidermidis, in the presence of PEG-8 Laurate, can mediate cyclophilin A to elicit an electrical current that has anti-C. acnes effects. Electricity generated by S. epidermidis may confer immediate innate immunity in acne lesions to rein in the overgrowth of C. acnes at the onset of acne vulgaris.

Features of the immune status in patients with chronic and complicated pyodermas: choice of a therapeutic correction method

Introduction: To compare the features of the immune status in patients with chronic and complicated pyoderma in the course of complex pharmacotherapy using immunomodulators based on transfer factors and glucosaminylmuramyldipeptide.

Materials and methods: A clinical examination of 107 patients with pyoderma, divided into three groups, was carried out. All individuals underwent immunological examination before and after etiopathogenetic treatment. The patients of the first group were additionally treated with a drug containing signaling immunoactive molecules (transfer factor) as an immunomodulator; the patients of the second group received glucosaminylmuramyldipeptide; and the patients of the third group received standard antibacterial therapy.

Results and discussion: Prior to the beginning of pathogenetic therapy, the patients were found to lack non-specific mechanisms of antimicrobial protection; there was a decrease in the activity and intensity of phagocytosis: phagocytic index and phagocytic number of neutrophils by 1.2 and 1.3 times; the production of proinflammatory cytokines IL-6 increased by 2.3 times, IL-8 –by 2.1 times, and TNFa – by 2.4 times. The study of immunological parameters after the inclusion of immunomodulators into the therapy revealed an increase in the phagocytic activity of neutrophils, and the indicators of the NST test were close to the control ones. The production of proinflammatory cytokines in the blood serum was restored to the level of the healthy individuals. Normalization of the number of CD4+-, CD8+-, CD19+-cells was observed in 86.0 ± 3% of the patients. At the same time, against the background of the use of glucosaminylmuramyldipeptide, a more intensive recovery of all links of anti-infectious immunity was recorded in comparison with the group where transfer factor molecules were used.

Conclusion: A drug based on glucosaminylmuramyldipeptide can be recommended as the drug of choice in non-specific immunocorrection for complex pharmacotherapy of pyoderma accompanied by secondary immune insufficiency, in comparison with a drug containing transfer factors.

Treatment challenges in adult female acne and future directions

Introduction: Acne is a chronic, inflammatory, and immune-mediated disease of the pilosebaceous unit, highly prevalent in adolescents. However, an increasing number of adults over 25 years old with facial acne, particularly women, have been observed. It is considered a different disease when compared to acne vulgaris. Face is the mainly involved area with inflammatory lesions and more sensitive skin, pointing out the need of a holistic approach.Areas covered: We performed a comprehensive literature search on PubMed database, up to January 2021, regarding adult female acne. We synthesized data about pathogenesis; differences compared to acne vulgaris; and treatment, with focus in the management challenges and perspectives.Expert opinion: It is essential to value the negative impact on quality of life of adult female acne, independently of severity. The disease has prolonged evolution, and patient might be resilient once the improvement, regardless of the treatment option, will just be noticeable after 3 months. Aggravating factors should be clearly discussed, such as the need of changing many habits, especially lesions manipulation. The therapeutic regimen includes make-up and tailored skin care (considering proneness to sensitivity), while anti-acne drugs should be chosen in accordance with desire to be pregnant, presence of pregnancy or breastfeeding.

Gene variants associated with acne vulgaris presentation and severity: a systematic review and meta-analysis

BACKGROUND

Multiple factors have been attributed to acne vulgaris predisposition and individual variations in the severity of skin symptoms, and genetics stood out as one of the major factors.

METHODS

We performed a systematic review on the genes and their variants that have been investigated for association with acne presentation and severity. A random-effect meta-analysis using the allele model (minor allele vs. major allele) was also conducted to provide an overall estimation of risk effects of frequently reported gene variants. This included a subset data of 982 acne cases and 846 controls extracted from our existing GWAS database on various allergic and skin diseases among Singapore Chinese.

RESULTS

Systematic review of 51 articles covering Asians and Caucasians found 60 genes/loci and their 100 variants implicated in acne; majority of them were in the intron, coding region/missense, and promoter regions. The commonly studied candidate genes/gene families include tumor necrosis factor (TNF), and the interleukin (IL) and cytochrome P450 (CYP) gene families. Our meta-analysis showed that most of the analyzed gene variants exhibited insignificant pooled odds ratio (pOR) and significant heterogeneity between studies. Nevertheless, we found that TNF rs1800629 A allele carriers and CYP17A1 rs743572 T allele carriers had significantly reduced mild acne risk [pOR: 0.60; 95% Confidence Interval (CI): 0.33-0.86] and severe acne risk (pOR: 0.59; 95% CI: 0.40-0.79), respectively, across populations. Overall, FST (follistatin) rs629725 A allele poses a significantly modest increased risk for acne presentation (pOR: 1.19, 95% CI: 1.14, 1.23), but neither TIMP2 (TIMP metallopeptidase inhibitor 2) rs8179090 nor CYP1A1 rs4646903 (pOR: 0.96, 95% CI: 0.80-1.12; pOR: 0.95, 95% CI: 0.83, 1.08), respectively. We discovered 15 novel SNPs in the 3' UTR region of the Toll-like Receptor 4 gene (TLR4) associated with acne presentation.

CONCLUSIONS

This systematic review and meta-analysis suggest that genes influencing inflammatory responses, specifically TNF, and genes influencing the function and activity of sebaceous glands, specifically CYP17A1 and FST, have potential risk variants for acne presentation and severity across populations. Understanding the genetic susceptibility factors and biological pathways involved in the pathogenesis of acne will help us to gain insights into developing effective acne treatments.

Vitamin D status and efficacy of vitamin D supplementation in acne patients: A systematic review and meta-analysis

BACKGROUND

Acne vulgaris, a chronic inflammatory dermatosis, affects approximately 85% of adolescents and young adults.The level of vitamin D in acne patients and the effect on acne patients of a vitamin D supplementation have previously been documented; however, it remains to be disputed whether vitamin D deficiency is normal in acne patients.

AIMS

This paper explores the relationship between vitamin D and acne levels and the advantageous implications of vitamin D supplements on acne.

METHODS

From every database start date until December 2020, we checked the PubMed, EMBASE, MEDLINE and the Cochrane libraries. Case-controls or randomized controlled trial reporting on the serum 25(OH)D level and the efficacy of vitamin D supplement to acne patients were included.

RESULTS

The serum 25(OH)D levels in acne patients is lower (standardized mean difference = -7.66 ng/ml; 95% confidence interval (CI) = -10.92 to -4.40). Articles also revealed the prospect of a therapeutic breakthrough through the supplementing of vitamin D for acne patients.

CONCLUSION

Our research offers a new guide in the field of acne prevention and health care.

Involvement of Pattern Recognition Receptors in the Direct Influence of Bacterial Components and Standard Antiacne Compounds on Human Sebaceous Gland Cells

INTRODUCTION

Pattern recognition receptors are involved in innate and adaptive immunity by detecting microbial components. Bacteria have been accused to play a role in inflammatory acne. We investigated the potential involvement of Toll-like receptor (TLR)2, TLR4, TLR6, and CD14 in the direct influence of bacterial components and standard antiacne compounds on human sebocytes.

METHODS

mRNA and protein expression of TLR2, TLR4, TLR6, and CD14 in SZ95 sebocytes was evaluated by real-time qRT-PCR and immunocytochemistry. The effects of lipopolysaccharides (LPS) and lipoteichoic acid on TLR2, TLR4, and CD14 expression and of cytokine/chemokine secretion by 13-cis-retinoic acid, all-trans-retinoic acid, retinol, and hydrocortisone at the mRNA and protein levels were assessed by real-time qRT-PCR and ELISA and verified by cocultivation with neutralizing antibodies.

RESULTS

The constitutive expression of TLR2, TLR4, and CD14 in SZ95 sebocytes was augmented by exposure to LPS. Hydrocortisone induced TLR2, but markedly reduced TLR4 expression. 13-cis-retinoic acid and all-trans-retinoic acid regulated IL-6 release. LPS enhanced and hydrocortisone reduced cytokine and chemokine release. Anti-TLR4 and anti-CD14 mAb blocked LPS-induced IL-8 and IL-6 release.

CONCLUSIONS

Microbial components use pattern recognition receptors to directly activate sebocytes to express a wide range of proinflammatory molecules and especially IL-8 and IL-6 in a TLR4- and CD14-specific manner. Retinoids, but mostly corticosteroids, also use this pathway to exhibit anti-inflammatory effects.

Anti-acne vulgaris effects of chlorogenic acid by anti-inflammatory activity and lipogenesis inhibition

Chlorogenic acid (CGA) exhibits substantial biological function in antioxidant, antibacterial, anti-lipogenesis and anti-inflammatory activities. Increased sebum production and inflammation are considered important for the development of acne. However, the therapeutic effects of CGA on acne vulgaris remain unexplored. In this study, to assess the effects and underlying mechanisms of CGA on acne, a model of skin inflammation in ears of ICR mouse induced by living Propionibacterium acnes was used. 24 hours after 1.0 × 107 CFU, P. acnes were intradermally injected into the ears of the ICR mouse. 1, 5 and 10 mg of CGA mixed with vaseline were applied to the surface of the skin every 12 hours for 3 days. Then, skin inflammation in the ears was assessed and the change of SREBP1 and TNF-α expression was analysed after CGA treatment. The mechanisms of CGA in anti-inflammatory activity and lipogenesis were also studied in primary sebocytes and HaCaT cells. We found that CGA treatment effectively rescued ear swelling, redness and erythema skin in ears of ICR mouse induced by P. acnes and significantly downregulated the expression of inflammatory cytokines by reducing the activity of the NF-κB signalling pathway. Furthermore, CGA could inhibit lipogenesis at the protein secretion and transcription level by decreasing the AKT/mTOR/SREBP signalling pathway. Our findings suggest that CGA could become a potential alternative drug for the treatment of acne vulgaris.

Analytical tools and evaluation strategies for nanostructured lipid carrier-based topical delivery systems

INTRODUCTION

The inception of nanostructured lipid carriers (NLCs) proved to be a revolutionary step toward the treatment of dermatological disorders. To uncover its true potential, it is imperative that the system be characterized and evaluated comprehensively.

AREAS COVERED

The present review has been written to furnish an in-depth account of analytical tools and evaluation procedures under one roof. Besides discussing the challenges of topical delivery and benefits of NLCs, the paper elaborates on their physicochemical characterization. Further, in vitro evaluation of NLCs for dermatological benefits, followed by their evaluation in a hydrogel/cream base is covered. Lastly, disease-specific evaluation of NLC-based formulations is presented.

EXPERT OPINION

The research endeavors for NLCs have largely focused on the fabrication of NLCs for different bioactives. However, scientific efforts should be aimed toward the lesser explored realm of NLCs, i.e. exploitation of analytical techniques, such as Parelectric spectroscopy, Electron Spin Resonance, and Nuclear Magnetic Resonance spectroscopy. NLCs have been proven for their potential to foster the therapeutic modalities applicable to cutaneous disorders. More attention needs to be devoted to their evaluation for disease-specific parameters. The futuristic steps must involve clinical studies, to lay the path for their commercialization.

Recent advances in understanding and managing acne

Multidisciplinary investigations into the pathogenesis of acne have significantly progressed over the past three years. Studies of the etiology of acne from the perspectives, for example, of sebaceous gland biology, sebum, genetics, keratinization, differentiation, hair cycles, immunology, bacteriology, and wound healing have elucidated its pathogenesis. This has led to the development of new therapies and paved the way for advanced studies that will enable the further evolution of acne treatment.

Role of KLF2: New insight in inflammatory acne pathogenesis

BACKGROUND

Acne is an inflammatory skin condition of pilosebaceous unit. Its pathogenesis is multifactorial with a central role of inflammatory and pro-inflammatory cytokines mediators. Downregulated Kruppel-like factor 2 (KLF2) leads to rapid secretion of many cytokines that are involved in acne pathogenesis.

AIMS

This study aimed at evaluating the level of KLF2 mRNA, clarifying its role in acne pathogenesis and its relation to acne lesion type, degree of severity, and outcome.

PATIENTS AND METHODS

The level of KLF2 mRNA was measured in 100 patients with acne and 50 age- and sex-matched healthy controls by using quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

The value of KLF2 mRNA was lower in acne patients than control group (P < .001), being lowest in inflammatory acne group (grades III, IV, and V) than noninflammatory acne group (grades I and II) and highest in the control group (P < .001). KLF2 mRNA was decreased significantly with increased acne severity grade (P < .001). KLF2 mRNA was lower in cases healed by scars than those healed by postinflammatory hyperpigmentation.

CONCLUSIONS

Decreased serum level of KLF2 is not only a claimed for AV pathogenesis but also a predictor for degree of acne severity and outcome.

In Vitro and Randomized, Double-Blind, Placebo-Controlled Trial to Determine the Efficacy and Safety of Nine Antiacne Medicinal Plants

The present in vitro and randomized, double‐blind, placebo‐controlled trial aims to determine the efficacy and safety of nine Mediterranean antiacne medicinal plants. The antimicrobial, antisebum, and anti-inflammatory activities of the plant extracts were evaluated in cells from the immortalized human keratinocytes (HaCaT) and human monocytic cell line (THP-1) as well as in a double-blind, randomized, and placebo‐controlled trial. Most of the extracts showed no significant cytotoxic effects on HaCaT cells up to 250 μg/ml. Inula helenium (IH) and Saponaria officinalis (SO) inhibited sebum production at 90 μg/ml and 30 μg/ml, respectively. The inhibition effect of SO on the growth of Cutibacterium acnes was 1.2 times higher than that of chloramphenicol. IH and SO extracts significantly inhibited the lipopolysaccharide- (LPS-) induced IL-6 and TNF-α production in THP-1 cells reaching the control levels of untreated cells at a concentration of 250 μg/ml. SO, IH, and Solanum nigrum (SN) extracts inhibited the nitric oxide (NO) production in a dose-dependent manner. Based on these results, an antiacne herbal cream (AHC) was prepared from different portions of extracts from SO, IH, and SN, and its efficacy was evaluated in a double-blind, randomized, and controlled efficacy study with 41 acne patients, ages 18–24, who were asked to apply AHC (n = 27) or a placebo (n = 14) two to three times daily for six weeks. Results obtained indicate that the AHC has unique synergistic effects that halt sebum production, combined with highly antiseptic and anti-inflammatory activity, in which 54.95% (t = 19.37 P < 0.001) of acne inflammatory and noninflammatory lesions disappeared after two weeks, 85.3%, after five weeks (t = 14.19 P < 0.001), and 91.4%, at the end of the sixth week of application (t = 5.7 P < 0.001). In conclusion, SO, IH, and SN as single extracts and in combination as AHC showed significant antimicrobial, antisebum, and anti-inflammatory activities in vitro and in a double-blind, randomized, and controlled antiacne efficacy. Therefore, AHC represents an interesting alternative treatment for acne.

Inhibitory and anti-inflammatory effects of two antimicrobial peptides moronecidin and temporin-1Dra against Propionibacterium acnes in vitro and in vivo

Proliferation of Propionibacterium acnes (P. acnes) is one of the main pathogenetic mechanisms of acne. Antimicrobial peptides with low-drug resistance and nonresidual are potential anti-acne agents. In this study, two antimicrobial peptides named temporin-1Dra and moronecidin were synthesized and tested their antimicrobial activity against P. acnes in vitro and in vivo. These two peptides inhibited the growth of Escherichia coli, Staphylococcus aureus, Candida albicans, and P. acnes. The minimal inhibitory concentrations (MICs) of temporin-1Dra and moronecidin to P. acnes were 30 and 10 μM, respectively. Both peptides exhibited strong resistance to heat and pH, but no obvious cytotoxicity to HaCaT cells. They also displayed persistent antimicrobial activities in the microbial challenge test. In the P. acnes-induced inflammation mouse model, moronecidin significantly decreased the ear swelling thickness in a concentration-dependent manner. At the 14th day after injection, 20 μg/day moronecidin reduced the ear swelling thickness to 46.15 ± 5.23% compared with the normal cream group. Tissue staining showed that moronecidin effectively reduced abscess and thickness of the dermis layer. Our results indicate that the antimicrobial peptide moronecidin could be developed as a potential natural anti-acne agent in the cosmetics or pharmaceutical industries.

Esc-1GN shows therapeutic potentials for acne vulgaris and inflammatory pain

The inflammatory response plays important roles in acne vulgaris and pain pathogenesis. In previous study, Esc-1GN with anti-inflammatory, antimicrobial, and lipopolysacchride (LPS) binding activity was identified from the skin of the frog Hylarana guentheri. Here, we report its therapeutic potentials for acne vulgaris and inflammatory pain. Esc-1GN destroyed the cell membrane of Propionibacteria acnes in the membrane permeability assays. In addition, bacterial agglutination test suggested that Esc-1GN triggered the agglutination of P. acnes, which was affected by LPS and Ca²⁺ . Meanwhile, in vivo anti-P. acnes and anti-inflammatory effects of Esc-1GN were confirmed by reducing the counts of P. acnes in mice ear, relieving P. acnes-induced mice ear swelling, decreasing mRNA expression and the production of pro-inflammatory cytokines, and attenuating the infiltration of inflammatory cells. Moreover, Esc-1GN also displayed antinociceptive effect in mice induced by acetic acid and formalin. Therefore, Esc-1GN is a promising candidate drug for treatment of acne vulgaris and inflammatory pain.

Inhibitory effect of the antimicrobial peptide BLP-7 against Propionibacterium acnes and its anti-inflammatory effect on acne vulgaris

Propionibacterium acnes (P. acnes) is a Gram-positive commensal bacterium, which is involved in the pathogenesis and inflammation of acne vulgaris. An antimicrobial peptide named bombinin-like peptide 7 (BLP-7), which was determined from Bombina orientalis, has been shown to possess certain antibacterial activity. This study was carried out with synthesized BLP-7 on the basis of the antimicrobial and anti-inflammatory activities against P. acnes in vitro and in vivo. The minimal inhibitory concentration (MIC) of BLP-7 against P. acnes is 5 μM. And BLP-7 exhibits strong resistance to heat, pH and salt concentration, but no significant cytotoxicity to normal human epidermal keratinocytes (NHEKs). Using the co-culture of P. acnes and NHEKs, this study demonstrated that BLP-7 significantly reduced the production of interleukin (IL)-8 and granulocyte-macrophage colony stimulating factor (GM-CSF), as well as the expression of these two pro-inflammatory cytokines at the transcriptional level. In a separate study, using the rat ear edema model, BLP-7 significantly suppressed P. acnes-induced skin inflammation, reducing the ear thickness by 54.21% of the negative control group. These results suggest that due to its anti-P. acnes and anti-inflammatory activities, BLP-7 could be used as a potential anti-acne agent.

Tissue expression of IL-17A and FOXP3 in acne vulgaris patients

BACKGROUND/OBJECTIVES

CD4⁺  T helper (Th) cells through its pro-inflammatory cell type, interleukin-17 (IL-17)-generating cells and its anti-inflammatory category forkhead box P3-positive (FOXP3⁺ ) regulatory T (Treg) cells, play a vital role in the immune balance in inflammatory disorders. Therefore, assessment of both IL-17 and FOXP3 in acne vulgaris (AV), a chronic inflammatory disease of the pilosebaceous unit, could be of value in understanding AV pathogenesis. This study aimed to investigate the immunohistochemical expression of IL-17A and FOXP3 in acne vulgaris lesions versus normal skin.

METHODS

Forty-five AV patients and 25 controls were included in this case-control study. Biopsies from participants were analyzed for IL-17A and FOXP3 immunohistochemical profiles using IL-17A and FOXP3 polyclonal antibodies.

RESULTS

Compared to controls, AV patients exhibited a significant increase of IL-17A percent of expression in epidermis (P ≤ .001), in lymphocytes in papillary dermis (P ≤ .001), and in perifollicular lymphocytic inflammatory infiltrate in AV lesions. Also, there was a significant elevation in FOXP3 percent of expression in epidermis (P = .049) and in lymphocytes in papillary dermis (P ≤ .027) in acne patients than control. A significant positive correlation between IL-17A expression in papillary lymphocytes and in epidermal keratinocyte was observed (r = .537, P = .001). In acne vulgaris patients, the associations between IL-17A and FOXP3 expressions could not reach level of significance.

CONCLUSIONS

There was an up-regulation of IL-17A and FOXP3 in acne vulgaris development, but with independent roles. Moreover, targeting of IL-17A and FOXP3 may open the door for development of new therapeutic agents in acne vulgaris treatment.

Topical azelaic acid, salicylic acid, nicotinamide, sulphur, zinc and fruit acid (alpha-hydroxy acid) for acne

BACKGROUND

Acne is an inflammatory disorder with a high global burden. It is common in adolescents and primarily affects sebaceous gland-rich areas. The clinical benefit of the topical acne treatments azelaic acid, salicylic acid, nicotinamide, sulphur, zinc, and alpha-hydroxy acid is unclear.

OBJECTIVES

To assess the effects of topical treatments (azelaic acid, salicylic acid, nicotinamide, zinc, alpha-hydroxy acid, and sulphur) for acne.

SEARCH METHODS

We searched the following databases up to May 2019: the Cochrane Skin Group Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trials registers.

SELECTION CRITERIA

Clinical randomised controlled trials of the six topical treatments compared with other topical treatments, placebo, or no treatment in people with acne.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Key outcomes included participants' global self-assessment of acne improvement (PGA), withdrawal for any reason, minor adverse events (assessed as total number of participants who experienced at least one minor adverse event), and quality of life.

MAIN RESULTS

We included 49 trials (3880 reported participants) set in clinics, hospitals, research centres, and university settings in Europe, Asia, and the USA. The vast majority of participants had mild to moderate acne, were aged between 12 to 30 years (range: 10 to 45 years), and were female. Treatment lasted over eight weeks in 59% of the studies. Study duration ranged from three months to three years. We assessed 26 studies as being at high risk of bias in at least one domain, but most domains were at low or unclear risk of bias. We grouped outcome assessment into short-term (less than or equal to 4 weeks), medium-term (from 5 to 8 weeks), and long-term treatment (more than 8 weeks). The following results were measured at the end of treatment, which was mainly long-term for the PGA outcome and mixed length (medium-term mainly) for minor adverse events. Azelaic acid In terms of treatment response (PGA), azelaic acid is probably less effective than benzoyl peroxide (risk ratio (RR) 0.82, 95% confidence interval (CI) 0.72 to 0.95; 1 study, 351 participants), but there is probably little or no difference when comparing azelaic acid to tretinoin (RR 0.94, 95% CI 0.78 to 1.14; 1 study, 289 participants) (both moderate-quality evidence). There may be little or no difference in PGA when comparing azelaic acid to clindamycin (RR 1.13, 95% CI 0.92 to 1.38; 1 study, 229 participants; low-quality evidence), but we are uncertain whether there is a difference between azelaic acid and adapalene (1 study, 55 participants; very low-quality evidence). Low-quality evidence indicates there may be no differences in rates of withdrawal for any reason when comparing azelaic acid with benzoyl peroxide (RR 0.88, 95% CI 0.60 to 1.29; 1 study, 351 participants), clindamycin (RR 1.30, 95% CI 0.48 to 3.56; 2 studies, 329 participants), or tretinoin (RR 0.66, 95% CI 0.29 to 1.47; 2 studies, 309 participants), but we are uncertain whether there is a difference between azelaic acid and adapalene (1 study, 55 participants; very low-quality evidence). In terms of total minor adverse events, we are uncertain if there is a difference between azelaic acid compared to adapalene (1 study; 55 participants) or benzoyl peroxide (1 study, 30 participants) (both very low-quality evidence). There may be no difference when comparing azelaic acid to clindamycin (RR 1.50, 95% CI 0.67 to 3.35; 1 study, 100 participants; low-quality evidence). Total minor adverse events were not reported in the comparison of azelaic acid versus tretinoin, but individual application site reactions were reported, such as scaling. Salicylic acid For PGA, there may be little or no difference between salicylic acid and tretinoin (RR 1.00, 95% CI 0.92 to 1.09; 1 study, 46 participants; low-quality evidence); we are not certain whether there is a difference between salicylic acid and pyruvic acid (1 study, 86 participants; very low-quality evidence); and PGA was not measured in the comparison of salicylic acid versus benzoyl peroxide. There may be no difference between groups in withdrawals when comparing salicylic acid and pyruvic acid (RR 0.89, 95% CI 0.53 to 1.50; 1 study, 86 participants); when salicylic acid was compared to tretinoin, neither group had withdrawals (both based on low-quality evidence (2 studies, 74 participants)). We are uncertain whether there is a difference in withdrawals between salicylic acid and benzoyl peroxide (1 study, 41 participants; very low-quality evidence). For total minor adverse events, we are uncertain if there is any difference between salicylic acid and benzoyl peroxide (1 study, 41 participants) or tretinoin (2 studies, 74 participants) (both very low-quality evidence). This outcome was not reported for salicylic acid versus pyruvic acid, but individual application site reactions were reported, such as scaling and redness. Nicotinamide Four studies evaluated nicotinamide against clindamycin or erythromycin, but none measured PGA. Low-quality evidence showed there may be no difference in withdrawals between nicotinamide and clindamycin (RR 1.12, 95% CI 0.49 to 2.60; 3 studies, 216 participants) or erythromycin (RR 1.40, 95% CI 0.46 to 4.22; 1 study, 158 participants), or in total minor adverse events between nicotinamide and clindamycin (RR 1.20, 95% CI 0.73 to 1.99; 3 studies, 216 participants; low-quality evidence). Total minor adverse events were not reported in the nicotinamide versus erythromycin comparison. Alpha-hydroxy (fruit) acid There may be no difference in PGA when comparing glycolic acid peel to salicylic-mandelic acid peel (RR 1.06, 95% CI 0.88 to 1.26; 1 study, 40 participants; low-quality evidence), and we are uncertain if there is a difference in total minor adverse events due to very low-quality evidence (1 study, 44 participants). Neither group had withdrawals (2 studies, 84 participants; low-quality evidence).

AUTHORS' CONCLUSIONS

Compared to benzoyl peroxide, azelaic acid probably leads to a worse treatment response, measured using PGA. When compared to tretinoin, azelaic acid probably makes little or no difference to treatment response. For other comparisons and outcomes the quality of evidence was low or very low. Risk of bias and imprecision limit our confidence in the evidence. We encourage the comparison of more methodologically robust head-to-head trials against commonly used active drugs.

Evaluation of 25-hydroxy vitamin D levels and disease severity in patients with acne vulgaris

Acne vulgaris is a multifactorial skin disorder. Many etiological factors are speculated to contribute to the pathogenesis of acne, one of these is vitamin D deficiency. Previous studies reported contradictory results about serum 25 hydroxy vitamin D (25-OH vitamin D) levels, its association with acne, some claimed that acne lesion might improve with vitamin D supplementation. We aimed to assess serum 25-OH vitamin D levels in acne patients, identify their relation with disease severity in a larger study group. The study included 134 acne patients, 129 controls. Acne disease severity was identified with Global Acne Grading Scale (GAGS) scores. Serum 25-OH vitamin D levels were measured in all groups. Serum 25-OH vitamin D levels were significantly lower in acne patients than in controls (P < .001). The prevalence of vitamin D deficiency was significantly higher in acne group than in control group (77.6% vs 63.9%; P = .041). There was a negative-strong statistically significant correlation detected between serum 25-OH vitamin D levels and GAGS scores in patient group (P < .001; r = -.910). According to these results, we claim that evaluating serum 25-OH vitamin D levels in acne patients, vitamin D supplementation as a treatment option may be a consideration for further studies.

Interaction of Cutibacterium acnes with human bone marrow derived mesenchymal stem cells: a step toward understanding bone implant- associated infection development

Crosstalk between mesenchymal stem cells (MSCs) and bacteria plays an important role in regulating the regenerative capacities of MSCs, fighting infections, modulating immune responses and maintaining tissue homeostasis. Commensal Cutibacterium acnes (C. acnes) bacterium becomes an opportunistic pathogen causing implant-associated infections. Herein, we examined MSCs/C. acnes interaction and analysed the subsequent bacteria and MSCs behaviours following infection. Human bone marrow derived MSCs were infected by two clinical and one laboratory C. acnes strains. Following 3h of interaction, all bacterial strains were able to invade MSCs. Viable intracellular bacteria acquired virulence factors by increasing biofilm formation and/or by affecting macrophage phagocytosis. Although the direct and indirect (through neutrophil stimulation) antibacterial effects of the MSCs secretome were not enhanced following C. acnes infection, ELISA analysis revealed that C. acnes clinical strains are able to license MSCs to become immunosuppressive cell-like by increasing the secretion of IL-6, IL-8, PGE-2, VEGF, TGF-β and HGF. Overall, these results showed a direct impact of C. acnes on bone marrow derived MSCs, providing new insights into the development of C. acnes during implant-associated infections. STATEMENT OF SIGNIFICANCE: The originality of this work relies on the study of relationship between human bone marrow derived mesenchymal stem cells (MSCs) phenotype and C. acnes clinical strains virulence following cell infection. Our major results showed that C. acnes are able to invade MSCs, inducing a transition of commensal to an opportunistic pathogen behaviour. Although the direct and indirect antibacterial effects were not enhanced following C. acnes infection, secretome analysis revealed that C. acnes clinical strains were able to license MSCs to become immunosuppressive and anti-fibrotic cell-like. These results showed a direct impact of C. acnes on bone marrow derived MSCs, providing new insights into the development of C. acnes during associated implant infections.

Anti-inflammatory effects of ozenoxacin, a topical quinolone antimicrobial agent

Ozenoxacin is a topical quinolone showing potent antimicrobial activities against Gram-negative and Gram-positive bacteria and is widely used for the treatment of inflammatory acne. However, the anti-inflammatory activities of ozenoxacin have not been examined so far. In the present study, we investigated the in vitro and in vivo anti-inflammatory effects of ozenoxacin. The production of interleukin (IL)-6 and IL-8 by human epidermal keratinocytes stimulated by heat-killed Cutibacterium acnes was significantly inhibited by ozenoxacin at concentrations from 1 to 30 μg ml⁻¹. Likewise, the production of IL-6, IL-8, and tumor necrosis factor alpha by stimulated THP-1 cells, a human monocyte cell line, was inhibited by ozenoxacin at concentrations from 1 to 30 μg ml⁻¹. The production of IL-1β by THP-1 was also inhibited by ozenoxacin at the concentration of 30 μg ml⁻¹. Phosphorylation of the mitogen-activated protein kinases and degradation of IκB-α, an inhibitory factor of NF-κB in keratinocytes and THP-1 cells, was increased by stimulation with heat-killed C. acnes. Of these activated intracellular pathways, the p38 phosphorylation pathway was remarkably reduced by ozenoxacin in both keratinocytes and THP-1 cells. In addition, the application of 2% ozenoxacin suppressed the increase in the ear thickness of rats induced by an intracutaneous injection of heat-killed C. acnes. These findings suggest that ozenoxacin possesses an anti-inflammatory activity, which may contribute to its therapeutic effects on inflammatory acne.

Integrated targeted serum metabolomic profile and its association with gender, age, disease severity, and pattern identification in acne

Background

Westernized diet and nutritional metabolism are important in acne pathogenesis, especially in adult patients. However, clinical and basic data are lacking. Pattern identification (PI) is a tool that results in a diagnostic conclusion based on a cluster of concurrent symptoms and signs in traditional medicine. Acne can be classified by PI. However, whether the metabolomic profile differs according to the PI of acne is unknown. Metabolomic data would help clarify the pathogenesis of acne.

Methods

We conducted a cross-sectional study involving 40 healthy controls and 60 subjects with acne. We evaluated androgens, serum lipids, essential amino acids, nonessential amino acids, other amino acids, and pro-inflammatory cytokines of all subjects and compared the metabolomic profiles between acne subjects and healthy controls, and in subgroups according to gender, age, severity, and PI.

Results

Dehydroepiandrosterone sulfate and serum fatty acids were significantly higher in female subjects, adolescents, and those with disharmony of the thoroughfare and conception vessels. The total essential and nonessential amino acids were significantly lower in the overall, female, adult, severe, and phlegm-stasis group. The latter group exhibited elevated serum levels of interleukin-1β and -6.

Conclusions

This is the first study to investigate serum lipids, amino acids, and cytokines in subjects with acne. We analyzed the differences between metabolomic profiles to determine the diagnostic value of PI. Prospective studies with more patients are needed to confirm the characteristics of each PI and lipidomic data will enrich knowledge concerning lipid mechanism.

Menopausal Acne - Challenges And Solutions

Although acne is a disease predominant in adolescence, it is being increasingly observed in adult life, including the menopausal period. The etiology of menopausal acne is multifactorial, with hormonal imbalance being the major culprit. There is a relative increase of androgens in the menopausal female that leads to clinical hyperandrogenism manifesting as acne, hirsutism and androgenetic alopecia. Other endocrine disorders including thyroid abnormalities, hyperprolactinemia and insulin resistance also play a role. Genetics, stress, dietary changes, lack of sleep and exercise and other lifestyle changes are implicated as trigger factors. Most menopausal women with isolated few acne lesions have normoandrogenic serum levels and do not require extensive investigations. However, baseline investigations including total testosterone are useful. Patients must also be evaluated for associated comorbidities such as obesity, diabetes, hypertension and dyslipidemia. A detailed history can help to exclude polycystic ovarian syndrome, late-onset congenital adrenal hyperplasia or medications as a cause of acne. The evaluation of menopausal acne and the approach to treatment depend on the severity of acne and associated features. In patients with mild acne without virilization, prolonged topical therapy is the mainstay of treatment. Though combined oral contraceptives are effective, they are relatively contraindicated in the postmenopausal period. Spironolactone is the first choice of therapy in the subset of patients that require oral anti-androgen therapy. Procedural treatment can be useful as it can also help in the treatment of associated acne scars and concomitant skin aging. It is also important to focus on lifestyle changes such as reducing stress, controlling obesity, having a healthy diet, exercise and proper skin care routine to reduce acne. The focus of this article is on the clinical presentation and management challenges of menopausal acne, which represents a special subtype of acne.

A Real-Life, International, Observational Study Demonstrating The Efficacy Of A Cosmetic Emulsion In The Supportive Care Of Mild-To-Moderate Facial Acne

Purpose

Cosmetic emulsions are increasingly being used as supportive care products to alleviate the severe side effects and improve the clinical outcomes associated with conventional acne treatments. The objectives of this study were to determine, in a real-life setting, the global effectiveness of an emulsion with antiseborrheic, keratolytic and anti-Propionibacterium acnes activities as an adjunct to anti-acne therapy, and to evaluate the effect of the product on acne severity, noninflammatory and inflammatory lesions, hyperseborrhea, skin irritation and patient quality of life (QoL). Tolerance of the product was also assessed.

Patients and methods

This international observational study involved 3960 patients aged 12 years and over with mild-to-moderate acne. The conventional acne prescriptions for these patients were either initiated at inclusion or were reviewed. Reviewed prescriptions may have been left unchanged, switched, or an addition made to ongoing treatment. At inclusion, participants were instructed to apply the cosmetic product daily for 2–3 months in combination with their medical acne treatment.

Results

After 2 to 3 months of use, the combined therapy resulted in moderate-to-large improvements in acne in over 75% of the patients whose acne prescriptions were left unchanged (n=859). The combination treatment led to an improvement in acne severity (−38.3% change in the mean investigator’s global assessment score; p<0.0001) and QoL (−38.3% change in the mean Cardiff acne disability index score; p<0.0001), and reduced noninflammatory and superficial inflammatory lesions (−35.3% and −47.0%, respectively; p<0.0001), hyperseborrhoea (−40.6%; p<0.0001) and skin irritation (−37.2%; p<0.0001). Tolerance was very good.

Conclusion

Use of the cosmetic emulsion combined with conventional acne therapy significantly improved clinical outcomes and patient QoL, and was very well tolerated. The combined therapy may have improved patient satisfaction, leading to improved patient adherence and higher rates of therapeutic success.