New developments in our understanding of acne pathogenesis and treatment

Acne vulgaris, probiotics and the gut-brain-skin axis: from anecdote to translational medicine

Acne vulgaris has long been postulated to feature a gastrointestinal mechanism, dating back 80 years to dermatologists John H. Stokes and Donald M. Pillsbury. They hypothesised that emotional states (e.g. depression and anxiety) could alter normal intestinal microbiota, increase intestinal permeability, and contribute to systemic inflammation. They were also among the first to propose the use of probiotic Lactobacillus acidophilus cultures. In recent years, aspects of this gut-brain-skin theory have been further validated via modern scientific investigations. It is evident that gut microbes and oral probiotics could be linked to the skin, and particularly acne severity, by their ability to influence systemic inflammation, oxidative stress, glycaemic control, tissue lipid content, and even mood. This intricate relationship between gut microbiota and the skin may also be influenced by diet, a current area of intense scrutiny by those who study acne. Here we provide a historical background to the gut-brain-skin theory in acne, followed by a summary of contemporary investigations and clinical implications.

Diet in dermatology: Part I. Atopic dermatitis, acne, and nonmelanoma skin cancer

Patients commonly inquire about dietary modifications as a means to prevent or manage skin disease. Answering these questions is often challenging, given the vast and conflicting evidence that exists on this topic. This 2-part continuing medical education article summarizes the evidence to date to enable physicians to answer patients' questions in an evidence-based manner. Part I includes atopic dermatitis, acne, and nonmelanoma skin cancer. The role of dietary supplementation, dietary exclusion, food allergy, maternal diet, and breastfeeding in the development and/or prevention of atopic dermatitis is summarized. The dermatoendocrinologic mechanism for the effects of glycemic index/glycemic load and milk on acne is described, as well as related clinical evidence for dietary modifications. Finally, evidence and recommendations for restriction or supplementation of dietary factors in the prevention of nonmelanoma skin cancer, including fat, vitamins A, C, D, and E, and selenium, are reported.

Treatment of acne with tea tree oil (melaleuca) products: a review of efficacy, tolerability and potential modes of action

Over-the-counter acne treatments containing tea tree oil from the plant Melaleuca alternifolia are widely available, and evidence indicates that they are a common choice amongst those self-treating their acne. The aims of this review were to collate and evaluate the clinical evidence on the use of tea tree oil products for treating acne, to review safety and tolerability and to discuss the underlying modes of therapeutic action.

The flexible gene pool of Propionibacterium acnes

Propionibacterium acnes is a Gram-positive bacterium that is intimately associated with humans. The nature and consequences of this symbiosis are poorly understood; it might comprise both mutualistic and parasitic properties. Recent advances in distinguishing phylotypes of P. acnes have revealed that certain type I lineages are predominantly associated with acne vulgaris. Genome analyses revealed a highly conserved core genome and the existence of island-like genomic regions and possible mobile genetic elements as part of the flexible gene pool. The analysis of clustered regularly interspaced short palindromic repeats (CRISPR), found exclusively in type II P. acnes, recently revealed the presence of CRISPR spacers that derived from mobile genetic elements. These elements are present in a subset of P. acnes type I lineages. Their significance for type-specific host-interacting properties and their contribution to pathogenicity is currently under investigation.

Ligand-independent epidermal growth factor receptor hyperactivation increases sebaceous gland size and sebum secretion in mice

The epidermal growth factor receptor (EGFR) system is an established regulator of the development and homeostasis of the hair follicle and interfollicular epidermis. Here, we evaluated EGFR actions on the sebaceous glands (SGs) by employing Dsk5 mice, a mutant line in which the EGFR is constitutively activated in a ligand-independent manner. Compared to control littermates, Dsk5 mice showed increased sebum levels and enlarged SGs, which contained a higher number of cells and showed stronger proliferation. c-myc transcript levels were increased in Dsk5 skin, suggesting that c-myc mediates the proliferative stimuli of the EGFR in the SG. Analysis of differentiation markers revealed deregulated expression of Scd1 and Scd3, indicating that sebaceous lipogenesis is affected in Dsk5 mice. In conclusion, our study indicates that the EGFR is an important regulator of presebocyte proliferation, contributing to the final cell number, to the size and to the lipid output of SGs.

NF-κB/AP-1-targeted inhibition of macrophage-mediated inflammatory responses by depigmenting compound AP736 derived from natural 1,3-diphenylpropane skeleton

AP736 was identified as an antimelanogenic drug that can be used for the prevention of melasma, freckles, and dark spots in skin by acting as a suppressor of melanin synthesis and tyrosinase expression. Since macrophage-mediated inflammatory responses are critical for skin health, here we investigated the potential anti-inflammatory activity of AP736. The effects of AP736 on various inflammatory events such as nitric oxide (NO)/prostaglandin (PG) E₂ production, inflammatory gene expression, phagocytic uptake, and morphological changes were examined in RAW264.7 cells. AP736 was found to strongly inhibit the production of both NO and PGE₂ in lipopolysaccharide- (LPS-) treated RAW264.7 cells. In addition, AP736 strongly inhibited both LPS-induced morphological changes and FITC-dextran-induced phagocytic uptake. Furthermore, AP736 also downregulated the expression of multiple inflammatory genes, such as inducible NO synthase (iNOS), cyclooxygenase- (COX-) 2, and interleukin- (IL-) 1β in LPS-treated RAW264.7 cells. Transcription factor analysis, including upstream signalling events, revealed that both NF-κB and AP-1 were targeted by AP736 via inhibition of the IKK/IκBα and IRAK1/TAK1 pathways. Therefore, our results strongly suggest that AP736 is a potential anti-inflammatory drug due to its suppression of NF-κB-IKK/IκBα and AP-1-IRAK1/TAK1 signalling, which may make AP736 useful for the treatment of macrophage-mediated skin inflammation.

Inhibitory effects of bee venom on Propionibacterium acnes-induced inflammatory skin disease in an animal model

Propionibacterium acnes (P. acnes) is a major contributing factor to the inflammatory component of acne. The many prescription medications for acne allow for a large number of potential combination treatments. However, several antibiotics, apart from their antibacterial effects, exert side‑effects, such as the suppression of host inflammatory responses. Purified bee venom (BV) is a natural toxin produced by honeybees (Apis mellifera L.). BV has been widely used as a traditional medicine for various diseases. In the present study, to investigate the therapeutic effects of BV against P. acnes-induced inflammatory skin disease, P. acnes was intradermally injected into the ears of mice. After the injection, BV was applied to the skin surface of the right ear. Histological observation revealed that P. acnes induced a considerable increase in the number of infiltrated inflammatory cells. However, treatment with BV markedly reduced these reactions compared with the P. acnes-injected mice not treated with BV. Moreover, the expression levels of tumor necrosis factor (TNF)-α, and interleukin (IL)-1β were significantly reduced in the BV-treated mice compared with the untreated P. acnes-injected mice. In addition, treatment with BV significantly inhibited Toll-like receptor (TLR)2 and CD14 expression in P. acnes-injected tissue. The binding activity of nuclear factor-κB (NF-κB) and activator protein (AP)-1 was markedly suppressed following treatment with BV. The results from our study, using an animal model, indicate that BV exerts an inhibitory effect on inflammatory skin diseases. In conclusion, our data indicate that BV has potential for use as an anti-acne agent and may be useful in the pharmaceutical and cosmetics industries.

IL-17/Th17 pathway is activated in acne lesions

The mechanisms of inflammation in acne are currently subject of intense investigation. This study focused on the activation of adaptive and innate immunity in clinically early visible inflamed acne lesions and was performed in two independent patient populations. Biopsies were collected from lesional and non-lesional skin of acne patients. Using Affymetrix Genechips, we observed significant elevation of the signature cytokines of the Th17 lineage in acne lesions compared to non-lesional skin. The increased expression of IL-17 was confirmed at the RNA and also protein level with real-time PCR (RT-PCR) and Luminex technology. Cytokines involved in Th17 lineage differentiation (IL-1β, IL-6, TGF-β, IL23p19) were remarkably induced at the RNA level. In addition, proinflammatory cytokines and chemokines (TNF-α, IL-8, CSF2 and CCL20), Th1 markers (IL12p40, CXCR3, T-bet, IFN-γ), T regulatory cell markers (Foxp3, IL-10, TGF-β) and IL-17 related antimicrobial peptides (S100A7, S100A9, lipocalin, hBD2, hBD3, hCAP18) were induced. Importantly, immunohistochemistry revealed significantly increased numbers of IL-17A positive T cells and CD83 dendritic cells in the acne lesions. In summary our results demonstrate the presence of IL-17A positive T cells and the activation of Th17-related cytokines in acne lesions, indicating that the Th17 pathway is activated and may play a pivotal role in the disease process, possibly offering new targets of therapy.

Effects of washing of the face with a mild facial cleanser formulated with sodium laureth carboxylate and alkyl carboxylates on acne in Japanese adult males

BACKGROUND/PURPOSE

Washing the face with a mild cleanser is generally recommended for acne care. Occasionally, the general public has the misconception that acne is exacerbated by cleansers and furthermore it has concerns about inducing skin irritation and xerosis by intensive washing. Recently, we developed a new cleanser based on sodium laureth carboxylate and alkyl carboxylates (AEC/soap) that cleans sebum well without penetrating the stratum corneum.

METHODS

We designed a controlled clinical trial conducted on adult Japanese males with moderate or less acne. Twenty subjects washed their faces with AEC/soap base cleanser twice a day for 4 weeks. Assessment of the efficacy was conducted prior to the start of the study, and at the end of weeks 2 and 4.

RESULTS

Significant improvement of the acne was observed within 2 weeks, and acne lesions were not detectable in 25% of the subjects at week 4. Sebum secretion levels on the skin significantly increased on the forehead, but significantly decreased on the cheek which correlated with the improvement. No complaints of dryness or irritation occurred during the study.

CONCLUSION

Washing the face twice a day with facial cleanser based on AEC/soap is an effective care for moderate or less grade facial acne.

[Acne vulgaris]

Acne vulgaris is worldwide the most common skin disease. Acne is an inflammatory disorder in whose emergence androgens, PPAR ligands, the IGF-1 signaling pathway, regulating neuropeptides and environmental factors are probably involved. These factors interrupt the natural cycling process in the sebaceous gland follicle and support the transition of microcomedones to comedones and inflammatory lesions. Proinflammatory lipids and cytokines are mediators for the development of acne lesions. Bacterial antigens can potentate the inflammatory phenomena. Acne is predominantly treated with combination therapy. Selecting a treatment regimen depends on the exact classification of acne type and severity. The development of scars is the main criterion for the choice of systemic therapy. Retinoids for mild comedonal acne and the combination of retinoids with antibiotics and/or benzoyl peroxide for mild to moderate papulopustular acne are the drugs of first choice for topical treatment. The use of topical antibiotics is not recommended any more because of the development of resistant bacterial strains. Systemic antibiotics, in combination with topical retinoids and/or benzoyl peroxide, for moderate papular/nodular acne and isotretinoin for severe nodular/conglobate acne are the columns of systemic acne treatment. Systemic anti-androgens are used in women against moderate papulopustular acne. Due to advances in the understanding of the underlying inflammatory mechanisms in recent years the development of new therapeutic agents with good efficacy and better side effect profile should be expected in the future.

Cannabidiol exerts sebostatic and antiinflammatory effects on human sebocytes

The endocannabinoid system (ECS) regulates multiple physiological processes, including cutaneous cell growth and differentiation. Here, we explored the effects of the major nonpsychotropic phytocannabinoid of Cannabis sativa, (-)-cannabidiol (CBD), on human sebaceous gland function and determined that CBD behaves as a highly effective sebostatic agent. Administration of CBD to cultured human sebocytes and human skin organ culture inhibited the lipogenic actions of various compounds, including arachidonic acid and a combination of linoleic acid and testosterone, and suppressed sebocyte proliferation via the activation of transient receptor potential vanilloid-4 (TRPV4) ion channels. Activation of TRPV4 interfered with the prolipogenic ERK1/2 MAPK pathway and resulted in the downregulation of nuclear receptor interacting protein-1 (NRIP1), which influences glucose and lipid metabolism, thereby inhibiting sebocyte lipogenesis. CBD also exerted complex antiinflammatory actions that were coupled to A2a adenosine receptor-dependent upregulation of tribbles homolog 3 (TRIB3) and inhibition of the NF-κB signaling. Collectively, our findings suggest that, due to the combined lipostatic, antiproliferative, and antiinflammatory effects, CBD has potential as a promising therapeutic agent for the treatment of acne vulgaris.

New perspectives on antiacne plant drugs: contribution to modern therapeutics

Acne is a common but serious skin disease, which affects approximately 80% adolescents and young adults in 11-30 age group. 42.5% of men and 50.9% of women continue to suffer from this disease into their twenties. Bacterial resistance is now at the alarming stage due to the irrational use of antibiotics. Hence, search for new lead molecule/bioactive and rational delivery of the existing drug (for better therapeutic effect) to the site of action is the need of the hour. Plants and plant-derived products have been an integral part of health care system since time immemorial. Therefore, plants that are currently used for the treatment of acne and those with a high potential are summarized in the present review. Most active plant extracts, namely, P. granatum, M. alba, A. anomala, and M. aquifolium exhibit minimum inhibitory concentration (MIC) in the range of 4-50 µg/mL against P. acnes, while aromatic oils of C. obovoides, C. natsudaidai, C. japonica, and C. nardus possess MICs 0.005-0.6 μL/mL and phytomolecules such as rhodomyrtone, pulsaquinone, hydropulsaquinone, honokiol, magnolol, xanthohumol lupulones, chebulagic acid and rhinacanthin-C show MIC in the range of 0.5-12.5 μg/mL. Novel drug delivery strategies of important plant leads in the treatment of acne have also been discussed.

Nasal microenvironments and interspecific interactions influence nasal microbiota complexity and S. aureus carriage

The indigenous microbiota of the nasal cavity plays important roles in human health and disease. Patterns of spatial variation in microbiota composition may help explain Staphylococcus aureus colonization and reveal interspecies and species-host interactions. To assess the biogeography of the nasal microbiota, we sampled healthy subjects, representing both S. aureus carriers and noncarriers at three nasal sites (anterior naris, middle meatus, and sphenoethmoidal recess). Phylogenetic compositional and sparse linear discriminant analyses revealed communities that differed according to site epithelium type and S. aureus culture-based carriage status. Corynebacterium accolens and C. pseudodiphtheriticum were identified as the most important microbial community determinants of S. aureus carriage, and competitive interactions were only evident at sites with ciliated pseudostratified columnar epithelium. In vitro cocultivation experiments provided supporting evidence of interactions among these species. These results highlight spatial variation in nasal microbial communities and differences in community composition between S. aureus carriers and noncarriers.

A Consensus on Acne Management Focused on Specific Patient Features

Background:

Most treatment guidelines for acne are based on clinical severity. Our objective was to expand that approach to one that also comprised individualized patient features: a case-based approach.

Methods:

An expert panel of Canadian dermatologists was established to develop demographic and clinical features considered to be particularly important in acne treatment selection. A nominal group consensus process was used for inclusion of features and corresponding appropriate treatments.

Results:

Consensus was achieved on the following statements: follicular epithelial dysfunction contributes to acne pathogenesis; inflammation from underlying disease(s) or prior treatment may impact further patient management; management focusing on specific patient features and on addressing psychosocial factors, including impact on quality of life, may improve treatment adherence and outcomes; and case-based scenarios are a practical approach to illustrate the effect of these factors. To address the latter, eight case profiles were developed.

Conclusions:

Management of acne should be based on multifactorial considerations beyond clinically determined acne severity and should include patient-reported impact, gender, skin sensitivity (including preexisting dermatoses), and phototype.

Risks of testosterone replacement therapy in men

Testosterone replacement therapy (TRT) is a widely used treatment for men with symptomatic hypogonadism. The benefits seen with TRT, such as increased libido and energy level, beneficial effects on bone density, strength and muscle as well as cardioprotective effects, have been well-documented. TRT is contraindicated in men with untreated prostate and breast cancer. Men on TRT should be monitored for side-effects such as polycythemia, peripheral edema, cardiac and hepatic dysfunction.

Challenges and promises in modeling dermatologic disorders with bioengineered skin

The tremendous cost of drug development is often attributed to the long time interval between identifying lead compounds in preclinical studies to assessing clinical efficacy in randomized clinical trials. Many candidate molecules show promise in cell culture or animal models, only to fail in late stage in human investigations. There is a need for novel technologies that allow investigators to quickly and reliably predict drug safety and efficacy. The advent of microtechnology has made it possible to integrate multiple microphysiologic organ systems into a single microfabricated chip. This review focuses on three-dimensional engineered skin, which has enjoyed a long history of uses both in clinical treatments of refractory ulcers and as a laboratory model. We discuss current biological and engineering challenges in construction of a robust bioengineered skin and provide a blueprint for its potential utility to model dermatologic disorders such as psoriasis or cutaneous drug reactions.

Isotretinoin therapy changes the expression of antimicrobial peptides in acne vulgaris

In acne vulgaris, antimicrobial peptides (AMPs) could play a dual role; i.e., protective by acting against Propionibacterium acnes, pro-inflammatory by acting as signalling molecules. The cutaneous expression of 15 different AMPs was investigated in acne patients; furthermore, the impact of isotretinoin therapy on AMP expression was analysed in skin biopsies from 13 patients with acne vulgaris taken before, during and after a 6-month treatment cycle with isotretinoin using quantitative real-time polymerase chain reaction. Cutaneous expression of the AMPs cathelicidin, human β-defensin-2 (HBD-2), lactoferrin, lysozyme, psoriasin (S100A7), koebnerisin (S100A15), and RNase 7 was upregulated in untreated acne vulgaris, whereas α-defensin-1 (HNP-1) was downregulated compared to controls. While relative expression levels of cathelicidin, HBD-2, lactoferrin, psoriasin (S100A7), and koebnerisin (S100A15) decreased during isotretinoin treatment, only those of cathelicidin and koebnerisin returned to normal after 6 months of isotretinoin therapy. The increased expression of lysozyme and RNase 7 remained unaffected by isotretinoin treatment. The levels of granulysin, RANTES (CCL5), perforin, CXCL9, substance P, chromogranin B, and dermcidin were not regulated in untreated acne patients and isotretinoin had no effect on these AMPs. In conclusion, the expression of various AMPs is altered in acne vulgaris. Isotretinoin therapy normalizes the cutaneous production of distinct AMPs while the expression of others is still increased in healing acne. Considering the antimicrobial and pro-inflammatory role of AMPs, these molecules could serve as specific targets for acne therapy and maintenance of clinical remission.

Antimicrobial and anti-inflammatory activities of endophytic fungi Talaromyces wortmannii extracts against acne-inducing bacteria

Acne vulgaris is the most common skin disease, causing significant psychosocial problems such as anxiety and depression similar to a chronic illness for those afflicted. Currently, obtainable agents for acne treatment have limited use. Thus, development of novel agents to treat this disease is a high medical need. The anaerobic bacterium Propionibacterium acnes has been implicated in the inflammatory phase of acne vulgaris by activating pro-inflammatory mediators such as the interleukin-8 (IL-8) via the NF-κB and MAPK pathways. Talaromyces wortmannii is an endophytic fungus, which is known to produce high bioactive natural compounds. We hypothesize that compound C but also the crude extract from T. wortmannii may possess both antibacterial activity especially against P. acnes and also anti-inflammatory properties by inhibiting TNF-α-induced ICAM-1 expression and P. acnes-induced IL-8 release. Treatment of keratinocytes (HaCaT) with P. acnes significantly increased NF-κB and activator protein-1 (AP-1) activation, as well as IL-8 release. Compound C inhibited P. acnes-mediated activation of NF-κB and AP-1 by inhibiting IκB degradation and the phosphorylation of ERK and JNK MAP kinases, and IL-8 release in a dose-dependent manner. Based on these results, compound C has effective antimicrobial activity against P. acnes and anti-inflammatory activity, and we suggest that this substance or the crude extract are alternative treatments for antibiotic/anti-inflammatory therapy for acne vulgaris.

Novel pharmacological approaches for the treatment of acne vulgaris

INTRODUCTION

Acne vulgaris is the most common skin disease worldwide; yet, current treatment options, although effective, are associated with unwanted side effects, chronicity, relapses and recurrences. The adequate control of the four pathogenic mechanisms, involved in the appearance of acne lesions, is paramount to treatment success.

AREAS COVERED

The authors discuss and evaluate the pathogenic pathways related to the mechanisms of action of novel molecules, which are currently under investigation for the treatment of acne vulgaris. The manuscript is based on comprehensive searches made through PubMed, GoogleScholar and ClinicalTrial.gov, using different combination of key words, which include acne vulgaris, pathogenesis, treatment, sebogenesis and Propionibacterium acnes.

EXPERT OPINION

In the near future, more effective treatments with fewer side effects are expected. The use of topical antiandrogens, acetylcholine inhibitors and PPAR modulators seem to be promising options for controlling sebum production. Retinoic acid metabolism-blocking agents and IL-1α inhibitors have the potential to become legitimate alternative options to retinoid therapy in the management of infundibular dyskeratosis. Indeed, the authors believe that there will likely be a decline in the use of antibiotics for controlling P. acnes colonization and targeting the inflammation cascade.

Propionibacterium acnes activates the NLRP3 inflammasome in human sebocytes

Propionibacterium acne and sebaceous glands are considered to have an important role in the development of acne. Although information regarding the activation of innate immunity by P. acnes in the sebaceous gland is limited, different P. acnes phylotypes and a higher prevalence of follicular P. acnes macrocolonies/biofilms in sebaceous follicles of skin biopsies from acne compared with control skin and occasionally single P. acnes clusters in single sebaceous glands have been detected. In this study, we investigated whether P. acnes activates the inflammasome in human sebaceous glands in vivo and in vitro. We found that IL-1β expression was upregulated in sebaceous glands of acne lesions. After stimulation of human sebocytes with P. acnes, the activation of caspase-1 and secretion of IL-1β were enhanced significantly. Moreover, knocking down the expression of NLRP3 abolished P. acnes-induced IL-1β production in sebocytes. The activation of the NLRP3 inflammasome by P. acnes was dependent on protease activity and reactive oxygen species generation. Finally, we found that NALP3-deficient mice display an impaired inflammatory response to P. acnes. These results suggest that human sebocytes are important immunocompetent cells that induce the NLRP3 inflammasome, and that P. acnes-induced IL-1β activation in sebaceous glands may have a role in combating skin infections and in acne pathogenesis.

Not all acne is acne vulgaris

BACKGROUND

Acne is the most common skin disease in adolescence, with a prevalence of nearly 100%. About 60% of affected adolescents have mild acne for which they use non-prescription preparations without consulting a physician. The remaining 40% constitute the population of acne patients seen in medical practice. The course of acne can be either acute or chronic; its manifestations can appear in waves, sometimes with dramatically severe inflammation leading rapidly to scarring. Acne often has adverse emotional consequences. Its treatment is markedly better than in the past because of new pharmacological and physicochemical approaches and because evidence-based guidelines are now available.

METHOD

This article is based on a selective review of the literature and also incorporates the authors' own clinical and scientific experience.

RESULTS

Acne vulgaris of grade I or II in an adolescent is generally not hard to treat. In contrast, the more severe grades III and IV and conglobate acne often present a therapeutic challenge, as they are associated with varying constellations of acute lesions, scarring, inflammation, and emotional disturbances. These conditions often require systemic treatment with tetracyclines, which are especially useful because of their para-antibiotic antiinflammatory effect. Severe cases must be treated with isotretinoin. Women can benefit from anti-androgenic contraceptive drugs. Retinoids or azelaic acid are used in maintenance therapy to suppress the formation of microcomedones, the precursor stage of acne lesions.

CONCLUSION

A variety of effective treatments for acne are available, depending on the severity of the condition.

New insights into acne pathogenesis: propionibacterium acnes activates the inflammasome

The precise contribution of the commensal bacterium Propionibacterium acnes (P. acnes) in the inflammatory response associated with acne vulgaris remains controversial. In this issue Qin et al. show that P. acnes induces robust IL-1β secretion in monocytic cells by triggering the activation of the NLRP3 inflammasome. In vivo, the encounter of P. acnes and macrophages in the peri-follicular dermis could locally result in the release of substantial amounts of IL-1β and therefore exacerbate inflammation. Such findings suggest that molecules targeting IL-1β and/or the NLRP3 inflammasome may constitute new treatment possibilities for acne vulgaris.

Acne vulgaris

Acne vulgaris is a chronic inflammatory disease of the pilosebaceous unit and it is observed equally in both sexes and nearly all races. It generally begins at puberty, but the healing period is variable. There is no known etiological factor, except genetic tendency. Androgens play a very limited role in some female patients. The effects of cosmetics, foods and drinks are also discussible and too limited. There are four factors in acne pathogenesis: Increase of the sebum excretionKeratinization of infrainfundibulumBacterial colonization of the follicleInflammation It is mainly observed on the face and back, shoulders and chest. Initial lesions are comedons. Papules, pustules and cysts of severe types follow it. The most important factor in treatment is a very good patient-physician communication. Topical or systemic treatment or both can be used depending on the severity of acne. Benzoyl peroxyde, azelaic acid, AHA's antibiotics, retinoic acid and derivatives are the topical choices. For systemic treatment antibiotics are the most commonly used medicines, but isotretinoine has a very spesific place with the possibility of permanent healing. All kind of treatments need approximately six months for a good result.

Effect of antihistamine as an adjuvant treatment of isotretinoin in acne: a randomized, controlled comparative study

BACKGROUND

Isotretinoin has been frequently used for acne therapy. However, it has limitation in acceptance because of its adverse effects. Although antihistamine recently revealed to decrease the lipogenesis, evidence is lacking regarding the clinical relevance of antihistamine in the treatment of acne.

OBJECTIVES

To evaluate the clinical efficacy and tolerability of antihistamine as an adjuvant treatment of isotretinoin.

METHODS

Forty patients with moderate acne were included in this randomized, controlled comparative study. Twenty patients were treated with isotretinoin and 20 patients were treated with additional antihistamine, desloratadine. Assessment was made at baseline, after 2, 4, 8 and 12 weeks of treatment.

RESULTS

At week 12, compared with isotretinoin only group, isotretinoin with additional antihistamine group showed more statistically significant decrease in acne lesion counts (non-inflammatory lesions: 44.8% vs. 17.8%; inflammatory lesions: 55.8% vs. 22.9%; total lesions: 45.6% vs. 18.7%; all P < 0.05). Significant decrease was also observed in the score of global acne grading system and the measured value of sebum and erythema. Moreover, acne flare during the treatment occurred less frequently and adverse events of isotretinoin were more tolerable in additional antihistamine group.

CONCLUSIONS

This results provide early evidence that antihistamine has a synergic effect with minimizing the side-effect of isotretinoin, and may be used as an adjuvant treatment of moderate acne.

Acne in patients with skin of color: practical management

Acne vulgaris is a prevalent and non-discriminatory condition affecting individuals of all races and ethnicities. As people with skin of color make up a rapidly expanding segment of the US population, dermatologic care must evolve accordingly to address their distinct concerns. Patients with skin of color with acne can be particularly challenging, given their potential for cosmetically disturbing complications, including post-inflammatory hyperpigmentation and keloid development. A variety of treatments have been shown to be effective in preventing or treating these complications. Topical retinoids are considered first-line therapy for acne in patients of color; topical alternatives include azelaic acid, dapsone, and antimicrobials. Hydroquinone may be used in combating post-inflammatory hyperpigmentation, specifically. For more severe acne, oral agents, including oral antibiotics or isotretinoin, may be used. Most recently, various lasers and phototherapies have been suggested for their safety and efficacy in patients with skin of color with acne. Ultimately, recognizing the clinical and histologic differences, as well as the variations in treatment regimens for darker skin types will allow for better care and patient satisfaction.

What is the role of antimicrobial peptides (AMP) in acne vulgaris?

Acne vulgaris is the most common disorder of the pilosebaceous unit leading to inflamed skin characterized by the formation of comedones, papules, pustules and scarring. There is increasing evidence that the abundance of Propionibacterium acnes (P. acnes) in the inflamed acne lesions triggers inflammation. Therefore, in addition to treatment with retinoids, the use of antimicrobial agents has been established as a treatment option for acne. This indicates that antimicrobial mechanisms to control the growth of P. acnes may have an important influence on the severity of inflammatory acne. One import antimicrobial innate defense system comprises the production of antimicrobial peptides (AMP), small molecules with a broad spectrum of antimicrobial activity as well as immunomodulatory properties. Although the role of AMP in acne is still emerging, there is increasing evidence that AMP may be of importance in acne. The aim of this viewpoint is to provide some hypotheses about the potential function of AMP in the pathogenesis of acne and to discuss potential AMP-based therapies for the treatment of acne.

Immunotherapy for acne vulgaris: current status and future directions

There is a high unmet clinical need for new and better treatments in acne vulgaris. Propionibacterium acnes has a strong proinflammatory activity and targets molecules involved in the innate cutaneous immunity, keratinocytes and sebaceous glands of the pilosebaceous follicle. The role of P. acnes in acne confers legitimacy on the possible benefits of immunization-based approaches, which may represent a solution for limiting the development of antibiotic-resistant P. acnes. Various immunization-based approaches have been developed over the last decades, including killed pathogen-based vaccines, vaccination against cell wall-anchored sialidase, monoclonal antibodies to the Christie, Atkins, Munch-Peterson factor of P. acnes, anti-Toll-like receptors vaccines and natural antimicrobial peptides. This review summarizes the current evidence and explores the challenges to making this a realistic treatment option for the future.

Current and future evidence-based acne treatment: a review

INTRODUCTION

Current acne treatment guidelines, as well as, treatment efficacy, safety, tolerability and patient preferences must all be considered in determining appropriate treatment regimes. Literature can assist physicians' evidence-based recommendations according to these factors.

AREAS COVERED

To determine the current and future direction of pharmacotherapy for treatment of acne, a PubMed search was conducted to identify all clinical trials involving the treatment of acne from 2009 to 2012. A total of 65 publications met inclusion criteria and were reviewed. Literature was heavily focused on the efficacy and tolerability of topical combination therapies and supported their use compared with monotherapy. A few studies on topical antiandrogens and antioxidants showed an alternative approach to targeting acne. Studies on oral monotherapy provided some evidence for the use of pulsed azithromycin for acne in adolescents. Literature also supports the use of low-dose isotretinoin for moderate acne, which was comparable in efficacy to high-dose regimes and better tolerated.

EXPERT OPINION

Combination acne therapy, whether it be combination topical therapy or combination oral and topical therapy, is well supported by recent studies. Given the multifactorial pathogenesis of acne and the hurdles of adherence to treatment, we anticipate greater development of and reliance on combination acne products in the future.

A double-blind, randomized, vehicle-controlled efficacy assessment study of a skin care formulation for improvement of mild to moderately severe acne

BACKGROUND

Inflammation, increased sebum production and P. acnes colonization are key factors in acne pathogenesis. Cosmetic formulations based on a combination of active compounds with in vitro proven anti-inflammatory, sebum regulating and P. acnes reducing properties may therefore contribute to improve the clinical signs and associated burden of disease.

OBJECTIVE

To provide in vivo proof-of-concept, we performed a 9-week, double-blind, randomized, vehicle-controlled study to assess the stand-alone efficacy of a skin care formulation containing licochalcone A, l-carnitine and 1,2-decanediol in volunteers with mild to moderately severe acne (10-25 inflammatory lesions) involving the face.

MATERIALS AND METHODS

After enrolment followed by a 1-week standardization of the cleansing procedure, 60 volunteers aged 14-40 years (40 women and 20 men, mean age 22.4 years) were randomized into two groups of 30 volunteers each, to apply either the active formulation or the vehicle twice daily on the face for 8 weeks. Reduction in the lesion count, P. acnes and sebum levels, stratum corneum hydration, Dermatology Life Quality Index (DLQI) and skin tolerability, assessed after 4 and 8 weeks were defined as outcomes.

RESULTS

Compared to baseline, the active formulation group showed at the end of the study a reduction in the mean total lesions count and papular lesions, significant reduction in the pustules (P < 0.05) and sebum levels (P < 0.01), marked reduction in P. acnes and improvement of DLQI. No significant changes in the respective parameters were found in the vehicle group. At the end of the study, greater reduction in the total lesion count, papules and pustules, P. acnes colonization, sebum production and more pronounced improvement of life quality in the active formulation group compared to the vehicle were found.

CONCLUSIONS

Our results provide evidence for improved outcomes in result of the application of the active formulation compared to the vehicle from both physician's and patient's perspective.

Acne as a chronic systemic disease

Acne is the most common skin disorder. In the majority of cases, acne is a disease that changes its skin distribution and severity over time; moreover, it can be a physically (scar development) and psychologically damaging condition that lasts for years. According to its clinical characteristics, it can be defined as a chronic disease according to the World Health Organization criteria. Acne is also a cardinal component of many systemic diseases or syndromes, such as congenital adrenal hyperplasia, seborrhea-acne-hirsutism-androgenetic alopecia syndrome, polycystic ovarian syndrome, hyperandrogenism-insulin resistance-acanthosis nigricans syndrome, Apert syndrome, synovitis-acne-pustulosis-hyperostosis-osteitis syndrome, and pyogenic arthritis-pyoderma gangrenosum-acne syndrome. Recent studies on the Ache hunter gatherers of Paraguay detected the lack of acne in association with markedly lower rates of obesity, diabetes mellitus, hyperlipidemia, and cardiovascular diseases, a finding that indicates either a nutritional or a genetic background of this impressive concomitance.

In vitro evaluation of the efficacy of chicken egg yolk antibodies (IgY) generated against Propionibacterium acnes

Acne vulgaris driven by multiple factors appears in almost two-third of the population. Increased resistance of the bacterium to antibiotics and cost-effective treatments have made us resort to alternative therapy.

OBJECTIVE

A novel method of targeting acne-causing bacterium Propionibacterium acnes with polyclonal chicken egg yolk antibodies was studied.

METHODS

Anti-Propionibacterium acnes antibodies were generated in white leghorn chickens by immunizing with antigen. The antibodies extracted from the egg yolk by polyethylene glycol method were subjected to the analysis. The antibody binding activity was evaluated by indirect ELISA. Further, inhibition efficiency of the antibodies was tested by growth inhibition assay, and biofilm inhibition was assessed by adherence test.

RESULTS

Titration of antibodies determined by ELISA was found to 0.323 after the first booster dose. The qualitative test for the determination of the binding activity revealed significant reduction in the colonies.

CONCLUSION

The results suggest that the egg yolk antibodies obtained from white leghorn chickens after immunization with the antigen may present as an alternative treatment option.

IL-1β drives inflammatory responses to propionibacterium acnes in vitro and in vivo

Acne vulgaris is potentially a severe skin disease associated with colonization of the pilo-sebaceous unit by the commensal bacterium Propionibacterium acnes and inflammation. P. acnes is considered to contribute to inflammation in acne, but the pathways involved are unclear. Here we reveal a mechanism that regulates inflammatory responses to P. acnes. We show that IL-1β mRNA and the active processed form of IL-1β are abundant in inflammatory acne lesions. Moreover, we identify P. acnes as a trigger of monocyte-macrophage NLRP3-inflammasome activation, IL-1β processing and secretion that is dependent on phagocytosis, lysosomal destabilization, reactive oxygen species, and cellular K+ efflux. In mice, inflammation induced by P. acnes is critically dependent on IL-1β and the NLRP3 inflammasome of myeloid cells. These findings show that the commensal P. acnes-by activating the inflammasome-can trigger an innate immune response in the skin, thus establishing the NLRP3-inflammasome and IL-1β as possible therapeutic targets in acne.

Evaluation of the Quantitative and Qualitative Alterations in the Fatty Acid Contents of the Sebum of Patients with Inflammatory Acne during Treatment with Systemic Lymecycline and/or Oral Fatty Acid Supplementation

Background. Acne is a dermatosis that involves an altered sebum pattern. Objectives. (1) To evaluate if a treatment based on antibiotics (lymecycline) can alter fatty acids contents of the sebum of patients with acne; (2) to evaluate if oral supplementation of fatty acids can interfere with fatty acids contents of the sebum of patients with acne; (3) to evaluate if there is any interaction in fatty acids contents of the sebum of patients with acne when they use both antibiotics and oral supplementation of fatty acids. Methods. Forty-five male volunteers with inflammatory acne vulgaris were treated with 300 mg of lymecycline per day, with 540 mg of γ-linolenic acid, 1,200 mg of linoleic acid, and 510 mg of oleic acid per day, or with both regimens for 90 days. Every 30 days, a sample of sebum from the forehead was collected for fatty acids' chromatographic analysis. Results. Twelve fatty acids studied exhibited some kind of pattern changes during the study: C12:0, C14:0, C15:0, C16:1, C18:0, C18:1n9c+C18:1n9t, C18:2n6t, C18:3n6, C18:3n3, C20:1, C22:0, and C24:0. Conclusions. The daily administration of lymecycline and/or specific fatty acids may slightly influence some fatty acids levels present in the sebum of patients with inflammatory acne vulgaris.