Novel anti-acne actions of nadifloxacin and clindamycin that inhibit the production of sebum, prostaglandin E2 and promatrix metalloproteinase-2 in hamster sebocytes

Ozenoxacin suppresses sebum production by inhibiting mTORC1 activation in differentiated hamster sebocytes

Acne vulgaris is a complex condition involving factors that affect the pilosebaceous unit. A primary manifestation of acne pathology is the development of comedones, often linked to the overproduction of sebum resulting from 5α-dihydrotestosterone (5α-DHT) and insulin activity. Ozenoxacin is a topical quinolone that exhibits potent antibacterial activity against Cutibacterium acnes (C. acnes). It is commonly used to treat acne associated with this bacterium; however, its effect on sebum production within the sebaceous glands remains unclear. In this study, the effects of ozenoxacin on sebum production were examined using insulin- and 5α-DHT-differentiated hamster sebocytes. Ozenoxacin showed a dose-dependent inhibition of lipid droplet formation and triacylglycerol (TG) production, which is a major component of sebum. In addition, it suppressed the expression of diacylglycerol acyltransferase 1, stearoyl-CoA desaturase-1, and perilipin-1 mRNA, all important factors involved in sebum synthesis, in a dose-dependent manner. Moreover, ozenoxacin decreased phosphorylated 40S ribosomal protein S6 levels downstream of the mechanistic/mammalian target of rapamycin complex 1 (mTORC1), without altering the phosphorylation of Akt, an upstream regulator of mTORC1, in both insulin- and 5α-DHT-treated hamster sebocytes. Interestingly, nadifloxacin, but not clindamycin, exhibited a similar suppression of sebum production, albeit with lesser potency compared with ozenoxacin. Furthermore, a topical application of a 2% ozenoxacin-containing lotion to the auricle skin of hamsters did not affect the size of the sebaceous glands or epidermal thickness. Notably, it decreased the amount of TG on the skin surface. The results provide novel insights into the sebum-inhibitory properties of ozenoxacin, indicating its potential efficacy in controlling microbial growth and regulating sebum production for acne management.

Particulate matter increases Cutibacterium acnes-induced inflammation in human epidermal keratinocytes via the TLR4/NF-κB pathway

Recent studies have demonstrated that particulate matter (PM) can induce oxidative stress and inflammatory responses that are related to the development or exacerbation of several inflammatory dermatoses. However, the effect of PM on acne vulgaris has yet to be determined. In this study, we induced acne-like inflammation in HEKn cells with several concentrations of Cutibacterium acnes (C. acnes) and Staphylococcus aureus peptidoglycan (PGN) to investigate whether PM exposure exacerbates acne-like inflammation and elucidate the underlying mechanisms. To confirm whether PM increases the messenger ribonucleic acid (mRNA) and protein levels of proinflammatory cytokines (IL-1α, IL-1β, IL-6, IL-8, and TNF-α) and cyclooxygenase (COX)-2 expression in C. acnes- or PGN-treated HEKn cells, we used quantitative real-time polymerase chain reactions, enzyme-linked immunosorbent assays, and western blot assays. The results demonstrated that C. acnes, PGN, and PM induced the expression of proinflammatory cytokines in a time- and dose-dependent manner at the mRNA and protein levels, respectively. Moreover, PM further increased the expression of proinflammatory cytokines, COX2, TLR4, and the phosphorylation of NF-κB in C. acnes- and PGN-treated HEKn cells. In conclusion, our results suggest that PM may exacerbate acne symptoms by increasing the inflammatory response.

Assoziation hypertropher Post‐Akne‐Narben mit Einzelnukleotid‐Polymorphismus (rs243865) im Matrix‐Metalloproteinase‐2‐ Gen

HINTERGRUND UND ZIEL

Bei Akne wurde eine abweichende Gewebeexpression von Matrix-Metalloproteinasen beobachtet. Ziel unserer Studie war es, die Bedeutung von Polymorphismen einzelner Nukleotide (single nucleotide polymorphisms, SNPs) in MMP-2 (-1306 C/T, rs243865) und TIMP-2 (-418 G/C, rs8179090) bei Akne und Post-Akne-Narben zu untersuchen.

PATIENTEN UND METHODEN

512 Patienten (169 mit Akne ohne Narbenbildung, 319 mit atrophen Aknenarben, 24 mit hypertrophen Aknenarben) und 161 gleichaltrige Kontrollen wurden nach Erhalt der schriftlichen Einwilligungserklärung aus der Ambulanz der Hautklinik in die Studie aufgenommen. Zur Genotypisierung mittels Polymerasekettenreaktion-Restriktionsfragmentlängenpolymorphismus (PCR-RFLP) wurde venöses Blut (5 ml) entnommen. Der Schweregrad von Akne und Akne-bedingter Narbenbildung wurde bestimmt.

ERGEBNISSE

Männer hatten ein deutlich erhöhtes Risiko schwere Akne (p = 0,012), Akne außerhalb des Gesichts (p = 0,047) und Aknenarben außerhalb des Gesichts (p = 0,0001) zu entwickeln. Entzündliche Akne korrelierte positiv mit dem Schweregrad der Narbenbildung (p = 0,001). Die Wahrscheinlichkeit für die Bildung hypertropher Narben war bei Personen mit homozygotem CC-Genotyp von MMP-2 (-1306 C/T) gegenüber Kontrollen nicht verändert (Faktor 1,0; p = 0,05; 95 %-KI: 0,7-1,6), jedoch gegenüber Personen mit Akne ohne Narbenbildung um den Faktor 7,8 (p = 0,047; 95 %-KI: 1,0-59,9) und gegenüber Personen mit atrophen Narben um den Faktor 8,2 (p = 0,041; 95 %-KI: 1,1-59,9) erhöht.

SCHLUSSFOLGERUNGEN

Es wurde eine signifikante Assoziation zwischen der Bildung hypertropher Post-Akne-Narben und dem CC-Genotyp von MMP-2 (-1306 C/T) beobachtet.

Hypertrophic post-acne scarring is associated with a single nucleotide polymorphism (rs243865) in the matrix metalloproteinase-2 gene

BACKGROUND AND OBJECTIVE

Aberrant tissue expression of matrix metalloproteinases has been observed in acne. Our objective was to study the relevance of MMP-2 (-1306 C/T, rs243865) and TIMP-2 (-418 G/C, rs8179090) single nucleotide polymorphisms (SNP) in acne and post-acne scarring.

PATIENTS AND METHODS

512 patients (169 having acne without scarring, 319 having atrophic acne scarring, 24 having hypertrophic acne scarring) and 161 age-matched controls were recruited from the Dermatology Outpatient Department after obtaining informed written consent. Venous blood (5 ml) was collected for genotyping by Polymerase Chain Reaction (PCR)-Restriction Fragment Length Polymorphism (RFLP) method. The severity of acne and acne-scarring were graded.

RESULTS

Males had a significantly increased risk of developing severe acne (P = 0.012), extra-facial acne (P = 0.047) and extra-facial acne scarring (P = 0.0001). The presence of inflammatory acne positively correlated with severity of scarring (P = 0.001). Subjects with a homozygous CC genotype of MMP-2 (-1306 C/T) had 1.0, 7.8 and 8.2 times the odds of developing hypertrophic scarring when compared to controls (P = 0.05, 95 % CI: 0.7-1.6), subjects having acne without scarring (P = 0.047, 95 % CI: 1.0-59.9) and subjects having atrophic scarring, respectively (P = 0.041, 95 % CI: 1.1-59.9).

CONCLUSIONS

A significant association was observed between hypertrophic post-acne scarring and the CC genotype of MMP-2 (-1306 C/T).

Platycodin D May Improve Acne and Prevent Scarring by Downregulating SREBP-1 Expression Via Inhibition of IGF-1R/PI3K/Akt Pathway and Modulating Inflammation with an Increase in Collagen

Background

Although many therapeutic agents have been developed, only a few drugs are known to target multiple pathogenic factors in the treatment of acne.

Objective

The purpose of this study was to identify a new drug candidate, platycodin D, which is a substance extracted from the root of Platycodon grandiflorum.

Methods

Using western blotting and Cell Counting Kit-8 assay, we studied the effects of platycodin D on SEB-1 sebocytes, fibroblasts, and keratinocytes. We investigated its effects in view of lipogenesis, collagen production, anti-inflammatory activity, and dyskeratinization.

Results

In SEB-1 sebocytes, platycodin D showed a sebosuppressive effect by downregulating ERK and insulin- like growth factor-1R/PI3K/Akt/sterol-regulatory element binding protein-1 signaling pathways. In addition, adiponectin, one of the adipokines responsible for sebum production, was decreased in platycodin D-treated SEB-1 sebocytes. In fibroblasts, platycodin D increased collagen production and reduced inflammation by inhibiting nuclear factor kappa B and matrix metalloproteinases. Platycodin D also showed anti-inflammatory effects on keratinocytes. It also suppressed keratin 16 expression induced by lipopolysaccharide. Furthermore, platycodin D showed no cytotoxicity on both SEB-1 sebocytes and fibroblasts.

Conclusion

Our data demonstrate the clinical feasibility of platycodin D for acne treatment and the prevention of acne scarring by sebosuppressive and anti-inflammatory effects, as well as through an increase in collagen levels.

The ameliorative effect of hemp seed hexane extracts on the Propionibacterium acnes-induced inflammation and lipogenesis in sebocytes

In this study, we investigated the anti-microbial, anti-inflammatory, and anti-lipogenic effects of hemp (Cannabis sativa L.) seed hexane extracts, focusing on the Propionibacterium acnes-triggered inflammation and lipogenesis. Hemp seed hexane extracts (HSHE) showed anti-microbial activity against P. acnes. The expression of iNOS, COX-2, and the subsequent production of nitric oxide and prostaglandin increased after infection of P. acnes in HaCaT cells, however, upon treating with HSHE, their expressions were reduced. P. acnes-induced expressions of IL-1β and IL-8 were also reduced. HSHE exerted anti-inflammatory effects by regulating NF-κB and MAPKs signaling and blunting the translocation of p-NF-κB to the nucleus in P. acnes-stimulated HaCaT cells. Moreover, P. acnes-induced phosphorylation of ERK and JNK, and their downstream targets c-Fos and c-Jun, was also inhibited by HSHE. In addition, the transactivation of AP-1 induced by P. acnes infection was also downregulated by HSHE. Notably, HSHE regulated inflammation and lipid biosynthesis via regulating AMPK and AKT/FoxO1 signaling in IGF-1-induced inflammation and lipogenesis of sebocytes. In addition, HSHE inhibited 5-lipoxygenase level and P. acnes-induced MMP-9 activity, and promoted collagen biosynthesis in vitro. Thus, HSHE could be utilized to treat acne vulgaris, through its anti-microbial, anti-inflammatory, anti-lipogenic, and collagen-promoting properties.

Emerging Therapies for Acne Vulgaris

As we gain a greater understanding of acne pathogenesis, both new agents as well as new uses for established drugs are being considered for the treatment of acne vulgaris. Multiple clinical trials assessing new formulations or combinations of established acne treatments have been conducted, and novel uses of antimicrobials such as modified diallyl disulfide oxide and nitric oxide are being assessed in clinical trials. There are also a multitude of new therapies currently being studied that target the inflammatory cascade of acne pathogenesis, including sebosuppressive and anti-inflammatory phytochemicals, and  small molecule inhibitors targeting sebaceous glands and enzymes, among others. Laser and light therapy is also being modified for the treatment of acne through combination methods with metal nanoshells and vacuum assistance. Probiotics have gained popularity in medicine as greater knowledge of the microbiome and its effects on multiple organ systems is being elucidated. Studies describing the positive effects of certain ammonia-oxidizing bacterial strains in the regulation of the skin's inflammatory response are ongoing. Therapies for acne are constantly evolving and current gold-standard acne therapy may be supplemented with novel treatment modalities in the near future.

The regulation effects of danofloxacin on pig immune stress induced by LPS

Danofloxacin (DAN) is one of the Fluoroquinolone drugs (FQs) that has been widely used in the control and prevention of bacterial infectious disease in animal production. Most of the FQs have an obvious protective effect against lipopolysaccharide (LPS) induced Immune stress. However, the effect of DAN on the host immune system of animals remains unknown. In this study, a fever piglet model was built and a systematic survey of the response of inflammatory genes and mediators to DAN treatment and LPS induction was performed in the pig. The results indicated that the IL-1β, TNF-α, IL-6, NO (nitric oxide), and PGE2 (prostaglandin E2) levels were significantly suppressed in plasma and porcine alveolar macrophage 3D4/2 cells compared with the LPS treatment group. Interestingly, the IL-10 production was further stimulated by DAN treatment in the LPS challenged piglet. Our results suggested that DAN could relieve acute inflammation through inhibiting the activation of inflammatory genes introduced by LPS.

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

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

Fillers for the improvement in acne scars

Acne is a common inflammatory disease. Scarring is an unwanted end point of acne. Both atrophic and hypertrophic scar types occur. Soft-tissue augmentation aims to improve atrophic scars. In this review, we will focus on the use of dermal fillers for acne scar improvement. Therefore, various filler types are characterized, and available data on their use in acne scar improvement are analyzed.

L-Ascorbyl-2-phosphate attenuates NF-κB signaling in SZ95 sebocytes without affecting IL-6 and IL-8 secretion

Acne is the most common inflammatory skin disease. Interleukin-1 (IL-1) is at the beginning of the cytokine signaling cascade and may be involved in the pathogenesis of this disorder. It activates redox-sensitive transcription factors, which induce IL-6 and IL-8 expression. Interestingly, l-ascorbyl-2-phosphate (APS) was shown to have beneficial effects in patients with acne vulgaris. The mechanism of action of this agent remains unknown. Here, we investigated if APS attenuates IL-1β- or TNF-α-mediated IL-6 and IL-8 expression in SZ95 sebocytes, whereas TNF-α was used as control. We also explored NF-κB activation which is known to orchestrate IL-1β- and TNF-α-mediated cytokine expression in many cell types. Both IL-1β and TNF-α increased IL-6 and IL-8 mRNA expression in SZ95 sebocytes. However, only IL-1β induced IL-6 and IL-8 secretion. IL-1β but not TNF-α activated NF-κB canonical signaling as demonstrated by Iκ-Bα phosphorylation and degradation as well as by nuclear accumulation of NF-κB/p65. Concomitant treatment of SZ95 sebocytes with APS attenuated the effect of IL-1β and TNF-α on IL-6 and IL-8 gene expression as well as on IL-1β-mediated NF-κB signaling. In contrast, APS failed to reduce IL-1β-mediated IL-6 and IL-8 secretion, presumably by maintained IL-1β-mediated p38 activation, which is known to control IL-8 secretion. Our findings shed light into the impact of IL-1β on the inflammatory cytokine response and its molecular mechanisms in human sebocytes. Our data further suggest that the beneficial effect of APS in acne patients involves attenuation of NF-κB signaling but not reduction of IL-6 or IL-8 secretion.

Propionibacterium acnes: an update on its role in the pathogenesis of acne

In recent years, significant progress has been made in the understanding of the pathophysiological mechanisms of acne and the role of Propionibacterium acnes. With this review, the authors aim to provide an update on the current understanding of the role of P. acnes in the development of acne lesions and analysing the potential implications for future treatments. A total of 188 articles published between January 1980 and March 2013 were searched using key words such as acne, P. acnes, microbiology, Corynebacterium acnes, acne vulgaris, pathogenesis, antibiotic, vaccination and a combination of those key words. From those articles, 77 were analysed in depth. Recent data confirm that P. acnes has a strong proinflammatory activity and targets molecules involved in the innate cutaneous immunity, keratinocytes and sebaceous glands of the pilosebaceous follicle and leads to the development of comedones. Furthermore, the profile of its different strains may differ between healthy subjects and acne patients. The better understanding of the role of P. acnes may allow for new perspectives in the treatment of acne. Novel therapies should target molecules implicated in the activation of innate immunity, including toll-like receptors, protease-activated receptors and topical antimicrobial peptides; the latter may be an alternative to topical antibiotics and thus a solution for limiting bacterial resistance induced by topical macrolides. Vaccines may also be promising. However, the most appropriate candidate remains to be selected.

Bioactive lipid mediators in skin inflammation and immunity

The skin is the primary barrier from the outside environment, protecting the host from injury, infectious pathogens, water loss and solar ultraviolet radiation. In this role, it is supported by a highly organized system comprising elements of innate and adaptive immunity, responsive to inflammatory stimuli. The cutaneous immune system is regulated by mediators such as cytokines and bioactive lipids that can initiate rapid immune responses with controlled inflammation, followed by efficient resolution. However, when immune responses are inadequate or mounted against non-infectious agents, these mediators contribute to skin pathologies involving unresolved or chronic inflammation. Skin is characterized by active lipid metabolism and fatty acids play crucial roles both in terms of structural integrity and functionality, in particular when transformed to bioactive mediators. Eicosanoids, endocannabinoids and sphingolipids are such key bioactive lipids, intimately involved in skin biology, inflammation and immunity. We discuss their origins, role and influence over various cells of the epidermis, dermis and cutaneous immune system and examine their function in examples of inflammatory skin conditions. We focus on psoriasis, atopic and contact dermatitis, acne vulgaris, wound healing and photodermatology that demonstrate dysregulation of bioactive lipid metabolism and examine ways of using this insight to inform novel therapeutics.