Prolonged remissions of cystic and conglobate acne with 13-cis-retinoic acid

Structure-Activity Relationships and Therapeutic Applications of Retinoids in View of Potential Benefits from Drug Repurposing Process

Vitamin A, an essential micronutrient, is integral to various biological processes crucial for organismal development and maintenance. Dietary sources of vitamin A encompass preformed retinol, retinyl esters, and provitamin A carotenoids. Retinoic acid (RA), a key component, plays pivotal roles in vision, cell proliferation, apoptosis, immune function, and gene regulation. Drug repurposing, an effective strategy for identifying new therapeutic applications for existing drugs, has gained prominence in recent years. This review seeks to provide a comprehensive overview of the current research landscape surrounding retinoids and drug repurposing. The scope of this review encompasses a comprehensive examination of retinoids and their potential for repurposing in various therapeutic contexts. Despite their efficacy in treating dermatological conditions, concerns about toxicity persist, driving the search for safer and more potent retinoids. The molecular mechanisms underlying retinoid activity involve binding to retinoic acid receptors (RARs) and retinoid X receptors (RXRs), leading to transcriptional regulation of target genes. This review seeks to shed light on the possibilities for repurposing retinoids to cover a wider spectrum of therapeutic uses by exploring recent scientific progress. It also aims to offer a more comprehensive understanding of the therapeutic prospects of retinoids and the broader impact of drug repositioning in contemporary medicine.

Early intervention and disease modification in atopic dermatitis-the current state of the field and barriers to progress

Atopic dermatitis (AD) is a highly prevalent chronic inflammatory skin disease representing a major source of global disability burden. Disease-modifying therapies are showing promise in chronic inflammatory disorders such as rheumatoid arthritis and Crohn's disease with method and timing of initial treatment impacting long-term disease outcomes. Whether disease-modifying therapies, specifically those used as an early interventional approach, impacts disease course and comorbidity development in AD is not well-understood. We reviewed the progress in disease modification strategies, emphasizing early intervention approaches in common (or proto-typical) inflammatory diseases. Although more common in other fields, disease modification approaches are becoming increasingly investigated in dermatology, though studies in AD are lacking. Despite significant limitations in ongoing and completed studies, early data are promising and suggest that both the choice and timing of early intervention approach can affect long-term disease course and comorbidity development. To best improve AD patient outcomes, more research is needed to further explore the impact of early disease-modifying therapies. Future studies should focus on identifying the most effective approaches and extend the early results to a more inclusive set of comorbidities and longer-term outcomes.

Acne Transcriptomics: Fundamentals of Acne Pathogenesis and Isotretinoin Treatment

This review on acne transcriptomics allows for deeper insights into the pathogenesis of acne and isotretinoin's mode of action. Puberty-induced insulin-like growth factor 1 (IGF-1), insulin and androgen signaling activate the kinase AKT and mechanistic target of rapamycin complex 1 (mTORC1). A Western diet (hyperglycemic carbohydrates and milk/dairy products) also co-stimulates AKT/mTORC1 signaling. The AKT-mediated phosphorylation of nuclear FoxO1 and FoxO3 results in their extrusion into the cytoplasm, a critical switch which enhances the transactivation of lipogenic and proinflammatory transcription factors, including androgen receptor (AR), sterol regulatory element-binding transcription factor 1 (SREBF1), peroxisome proliferator-activated receptor γ (PPARγ) and signal transducer and activator of transcription 3 (STAT3), but reduces the FoxO1-dependent expression of GATA binding protein 6 (GATA6), the key transcription factor for infundibular keratinocyte homeostasis. The AKT-mediated phosphorylation of the p53-binding protein MDM2 promotes the degradation of p53. In contrast, isotretinoin enhances the expression of p53, FoxO1 and FoxO3 in the sebaceous glands of acne patients. The overexpression of these proapoptotic transcription factors explains isotretinoin's desirable sebum-suppressive effect via the induction of sebocyte apoptosis and the depletion of BLIMP1(+) sebocyte progenitor cells; it also explains its adverse effects, including teratogenicity (neural crest cell apoptosis), a reduced ovarian reserve (granulosa cell apoptosis), the risk of depression (the apoptosis of hypothalamic neurons), VLDL hyperlipidemia, intracranial hypertension and dry skin.

Environmentally friendly stability-indicating HPLC method for the determination of isotretinoin in commercial products and solubility samples

In this study, an environmentally friendly "high-performance liquid chromatography (HPLC)" assay to quantify isotretinoin (ITN) in commercial products and solubility samples is designed and verified. A Nucleodur reverse-phase C18 column was used as the stationary phase to identify ITN. The ecologically friendly mobile phase was composed of ethyl acetate and ethanol (50:50 v/v), and it was delivered at a flow rate of 1.0 mL/min. ITN was measured at 354 nm in wavelength. The current HPLC method had a determination coefficient of 0.9994 and was linear in the 0.2-80 μg/g range. The current protocol for ITN measurement was also rapid (retention time = 2.78 min), accurate (%recoveries = 98.60-101.52), precise (% uncertainties = 0.71-0.98), and sensitive. According to the AGREE methodology, the current procedure received an outstanding greenness profile with an AGREE score of 0.76. By determining ITN in commercial products and solubility samples, the applicability of the current approach was proven. ITN was discovered to be present in 98.43% and 100.84%, respectively, of commercial capsule brands A and B. The ITN's solubility in numerous eco-friendly solvents was successfully measured. Under different stress conditions, the current approach was able to distinguish between its degradation products, demonstrating its stability-indicating characteristics. These findings indicated that ITN in procured capsules and solubility samples might be regularly tested by the suggested approach.

Isotretinoin treatment upregulates the expression of p53 in the skin and sebaceous glands of patients with acne vulgaris

The transcriptomic regulation induced by isotretinoin (13-cis retinoic acid) is still a matter of debate as short-term exposures of immortalized sebocytes with isotretinoin produced conflicting results. Based on translational evidence, it has been hypothesized that oral isotretinoin treatment upregulates the expression of the transcription factor p53. Twenty-five patients suffering from acne vulgaris were treated with isotretinoin (0.6 mg/kg body weight) for 6 weeks. Biopsies from back skin were taken before and after isotretinoin treatment for the determination of p53 expression by immunohistochemical staining, quantification of p53 protein concentration by enzyme-linked immunosorbent assay and TP53 gene expression by quantitative reverse transcription real time PCR. Fifteen socio-demographically cross-matched healthy volunteers served as controls. Isotretinoin treatment significantly increased the nuclear expression of p53 in sebaceous glands of treated patients compared to pre-treatment levels and p53 levels of untreated controls. Furthermore, the p53 protein and gene expression significantly increased in the skin after treatment. The magnitude of p53 expression showed an inverse correlation to acne severity score and body mass index. Under clinical conditions, isotretinoin induced the expression of p53, which controls multiple transcription factors involved in the pathogenesis of acne vulgaris including FoxO1, androgen receptor and critical genes involved in the induction of autophagy and apoptosis. Increased p53-FoxO1 signalling enhanced by systemic isotretinoin treatment explains the underlying transcriptomic changes causing sebum suppression but also the adverse effects associated with systemic isotretinoin therapy.

Truncal Acne and Scarring: A Comprehensive Review of Current Medical and Cosmetic Approaches to Treatment and Patient Management

Acne vulgaris is one of the most common skin disorders worldwide. It typically affects skin areas with a high density of sebaceous glands such as the face, upper arms, chest, and/or back. Historically, the majority of research efforts have focused on facial acne vulgaris, even though approximately half of patients with facial lesions demonstrate truncal involvement. Truncal acne vulgaris is challenging to treat and poses a significant psychosocial burden on patients. Despite these characteristics, studies specifically examining truncal acne vulgaris are limited, with treatment guidelines largely derived from facial protocols. Therefore, truncal acne remains an understudied clinical problem. Here, we provide a clinically focused review on the epidemiology, evaluation, and available treatment options for truncal acne vulgaris. In doing so, we highlight knowledge gaps with the goal of spurring further investigation into the management of truncal acne vulgaris.

The Effects of Isotretinoin on The Menstrual Cycle: A Cross-Sectional Study

Menstrual irregularities during isotretinoin therapy, including amenorrhea, can cause a great deal of health-status uncertainty such as the possibility of pregnancy. This study aimed to evaluate the effects of isotretinoin treatment on the menstrual cycle. This cross-sectional study was conducted among females aged between 15−45 years taking isotretinoin for acne. Descriptive statistics were used in the form of frequencies and percentages to represent categorical variables. Pearson’s chi-squared test was performed to assess the relationship between some of the variables with menstrual irregularities. A logistic regression model was performed to assess the risk factors for developing menstrual irregularities during isotretinoin therapy. Of participants with a known regular menstrual cycle, 10.4% were found to have irregularity in their cycle after starting the drug (p < 0.001). Amenorrhea was the most commonly reported menstrual irregularity in isotretinoin-treated females. Our results showed that single females, those who took isotretinoin for 10−12 months and who were concurrently taking hormonal contraceptives all have a statistically significant higher risk of developing menstrual irregularities than others. In conclusion, we found that a statistically significant number of participants with a regular menstrual cycle pre-isotretinoin intake developed irregularity in their cycle after starting the drug. The mechanism of how isotretinoin influences female hormonal imbalances, thereby affecting menstrual irregularities is still poorly understood and needs to be clarified in further clinical studies.

Isotretinoin and neuropsychiatric side effects: Continued vigilance is needed

Background

Isotretinoin (13-cis-retinoic acid, marketed under the names Accutane, Roaccutane, and others) is an effective treatment for acne that has been on the market for over 30 years, although reports of neuropsychiatric side effects continue to be reported. Isotretinoin is an isomer of the active form of Vitamin A, 13-trans-retinoic acid, which has known psychiatric side effects when given in excessive doses, and is part of the family of compounds called retinoids, which have multiple functions in the central nervous system.

Methods

The literature was reviewed in pubmed and psychinfo for research related to isotretinoin and neuropsychiatric side effects including depression, suicidal thoughts, suicide, mania, anxiety, impulsivity, emotional lability, violence, aggression, and psychosis.

Results

Multiple case series have shown that successful treatment of acne with isotretinoin results in improvements in measures of quality of life and self esteem However, studies show individual cases of clinically significant depression and other neuropsychiatric events that, although not common, are persistent in the literature. Since the original cases of depression were reported to the United States Food and Drug Administration, numerous cases have been reported to regulatory agencies in the United Kingdom, France, Ireland, Denmark, Australia, Canada, and other countries, making isotretinoin one of the top five medications in the world associated with depression and other neuropsychiatric side effects. Clinicians are advised to warn patients of the risks of neuropsychiatric side effects with isotretinoin which may arise from the medication itself, and not just as a side effect of acne or youth.

Vitamin A Update: Forms, Sources, Kinetics, Detection, Function, Deficiency, Therapeutic Use and Toxicity

Vitamin A is a group of vital micronutrients widely present in the human diet. Animal-based products are a rich source of the retinyl ester form of the vitamin, while vegetables and fruits contain carotenoids, most of which are provitamin A. Vitamin A plays a key role in the correct functioning of multiple physiological functions. The human organism can metabolize natural forms of vitamin A and provitamin A into biologically active forms (retinol, retinal, retinoic acid), which interact with multiple molecular targets, including nuclear receptors, opsin in the retina and, according to the latest research, also some enzymes. In this review, we aim to provide a complex view on the present knowledge about vitamin A ranging from its sources through its physiological functions to consequences of its deficiency and metabolic fate up to possible pharmacological administration and potential toxicity. Current analytical methods used for its detection in real samples are included as well.

The Effect of Isotretinoin on Oocyte Maturation in Adolescent Female Rats

OBJECTIVE

Isotretinoin is used in acne vulgaris treatment for more than 20 years. Isotretinoin has serious side effects on many organs, but there are no comprehensive studies investigating its possible toxic effects on reproductive organs. Thus, we aimed to investigate the possible toxic effects of isotretinoin administration on oocyte maturation in female rat gonads in this study.

METHODS

Thirty-two adolescent female rats (Wistar Albino, 220 ± 35 g) were randomly divided into 4 groups with 8 subjects in each group: group 1, group 2, group 3, and group 4. Different doses of isotretinoin which was dissolved in sesame oil were given to rats by gavage: 7.5 mg/kg/day in group 3 and 15 mg/kg/day in group 4. The rats in group 2 received sesame oil by gavage. To create gavage stress, only gavage was administered to the rats in group 1. The gavages for each group continued once a day and at a certain time for 30 days. To determine the effect of isotretinoin on oocyte maturation, the periodic acid-Schiff reaction was performed for histochemical and histomorphometric evaluation of the zona pellucida, and staining of growth differentiation factor-9 (GDF-9) and bone morphogenetic protein-15 (BMP-15) was performed for immunohistochemical analysis.

RESULTS

When the thickness of the zona pellucida was evaluated, a statistically significant difference was found between group 1 and experimental groups (group 3 and group 4). In the experimental groups, it was determined that the thickness of the zona pellucida was decreased depending on the increase in dose. GDF-9 and BMP-15 expressions in oocytes of primordial and primary follicles decreased significantly in the experimental groups compared to group 1 and group 2. However, the expression of GDF-9 and BMP-15 in oocytes of secondary follicles was not significantly different between group 1 and group 2 and the experimental groups.

CONCLUSIONS

In our study, we showed toxic effect of isotretinoin on oocyte maturation in female rats.

Repurposing Auranofin, an Anti-Rheumatic Gold Compound, to Treat Acne Vulgaris by Targeting the NLRP3 Inflammasome

Activation of the NLRP3 inflammasome is critical for host defense as well as the progression of inflammatory diseases through the production of the proinflammatory cytokine IL-1β, which is cleaved by active caspase-1. It has been reported that overactivation of the NLRP3 inflammasome contributes to the development and pathology of acne vulgaris. Therefore, inhibiting activation of the NLRP3 inflammasome may provide a new therapeutic strategy for acne vulgaris. In this study, we investigated whether auranofin, an anti-rheumatoid arthritis agent, inhibited NLRP3 inflammasome activation, thereby effectively treating acne vulgaris. Auranofin suppressed NLRP3 inflammasome activation induced by Propionibacterium acnes, reducing the production of IL-1β in primary mouse macrophages and human sebocytes. In a P. acnes-induced acne mouse model, injection of P. acnes into the ears of mice induced acne symptoms such as redness, swelling, and neutrophil infiltration. Topical application of auranofin (0.5 or 1%) to mouse ears significantly reduced the inflammatory symptoms of acne vulgaris induced by P. acnes injection. Topical application of auranofin led to the downregulation of the NLRP3 inflammasome activated by P. acnes in mouse ear skin. These results show that auranofin inhibits the NLRP3 inflammasome, the activation of which is associated with acne symptoms. The results further suggest that topical application of auranofin could be a new therapeutic strategy for treating acne vulgaris by targeting the NLRP3 inflammasome.

Isotretinoin in the management of acne vulgaris: practical prescribing

Since it was first approved for use in 1982, isotretinoin has revolutionized the management of acne vulgaris. Despite almost four decades of widespread use, uncertainty still exists regarding the manner in which it is best prescribed. In this review, we provide an update on the pharmacokinetics, mechanism of action, contraindications, interactions, and appropriate dosing schedule of isotretinoin in the treatment of acne. We also discuss the safety of performing concurrent dermatological procedures in patients taking isotretinoin.

A retrospective evaluation of laboratory parameters and hyperuricemia in patients with acne vulgaris under systemic isotretinoin treatment

BACKGROUND

Acne vulgaris is a chronic inflammatory disease affecting the pilosebaceous unit. Systemic isotretinoin (SI) is an effective, synthetic vitamin A derivative in the treatment of resistant acne or nodulocystic acne. This study aimed to investigate uric acid levels and laboratory parameters in patients receiving isotretinoin treatment.

MATERIALS AND METHODS

This study included 114 patients who were under SI treatment of 0.2-0.5 mg/kg/day aged between 17 and 44 years old. We retrospectively evaluated total cholesterol, triglyceride, aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, creatinine, creatinine kinase, uric acid, thrombocyte (Plt), and leucocyte (WBC) levels prior and on the fourth month of the treatment from the patients' records and compared these data statistically.

RESULTS

The AST, creatinine kinase, cholesterol, triglyceride, and thrombocyte levels were significantly different (p<.001, p<.001, p<.001, p<.001, and p=.02, respectively), and no statistically significant differences were noted among the uric acid, creatinine, ALT, and WBC levels in the comparison of the baseline values and values at the fourth month of treatment (p>.05).

CONCLUSIONS

SI treatment of 0.2-0.5 mg/kg/day did not make significant alterations on serum uric acid levels. Besides, all alterations occurred within normal ranges.

Retinoic Acid-Platinum (II) Complex [RT-Pt(II)] Protects Against Rheumatoid Arthritis in Mice via MEK/Nuclear Factor kappa B (NF-κB) Pathway Downregulation

Background

Rheumatoid arthritis (RA) is an inflammatory disorder that is present in approximately 1% of the world’s population. This study was aimed to investigate the effect of retinoic acid-platinum (II) complex [RT-Pt(II)] on rheumatoid arthritis (RA) and to explore the mechanism involved.

Material/Methods

MH7A cell viability was determined by MTT assay and apoptosis was assessed using FACSCalibur flow cytometry. RT-PCR and Western blot assays were used for assessment of mRNA and proteins levels.

Results

Treatment of rheumatoid arthritis with RT-Pt(II) significantly reduced the levels of IL-1β, IL-6, IL-8, MMP-1, and MMP-13 in synovial fluid of mice in a dose-dependent manner. The expression of iNOS and COX-2 mRNA and protein in rheumatoid arthritis rats was also significantly inhibited by treatment with RT-Pt(II). The TNF-α-induced proliferation of MH7A cells was alleviated by RT-Pt(II) treatment in a concentration-dependent manner. Moreover, RT-Pt(II) treatment induced apoptosis and caused arrest of cell cycle in MH7A cells. The activation of MEK/NF-κB pathway was downregulated by RT-Pt(II) treatment in MH7A cells.

Conclusions

In summary, the present study demonstrated that RT-Pt(II) inhibits TNF-α-induced inflammatory response, suppresses cell viability, and induces apoptosis in rheumatoid arthritis synovial cells. Moreover, RT-Pt(II) exhibited its effect through targeting the MEK/NF-κB pathway. Therefore, RT-Pt(II) can be used for the development of treatments for rheumatoid arthritis.

The use of isotretinoin for acne - an update on optimal dosing, surveillance, and adverse effects

INTRODUCTION

Acne is a chronic, inflammatory, and immune mediated disease of pilosebaceous unit, highly prevalent in adolescents. It involves face, trunk, and back; may leave scars and affect quality of life. Early, effective, and safe treatment is the key for disease resolution. Oral isotretinoin is the unique treatment for cure or prolonged remission for moderate and severe acne, preventing psychosocial impact and scars. It inhibits sebaceous glands activity and has anti-inflammatory and immunoregulatory properties.

AREAS COVERED

We performed a comprehensive literature search on PubMed database, up to March 2020, regarding oral isotretinoin for acne treatment. We synthetized data about acne pathogenesis and mechanism of action, efficacy, and safety of isotretinoin.

EXPERT OPINION

This drug is effective, despite common, controllable, and reversible mucocutaneous side effects. Serious adverse events are rare and represent individual reactions. Teratogenicity is the most severe, requiring rigorous control. We believe that no other therapeutic option, even topicals combined to oral antibiotics accomplish same results. Recurrence after treatments other than isotretinoin is the rule, prolonging risk of scars, compromising skin appearance, and causing emotional distress in teenagers. If there is no absolute contraindication, isotretinoin should be the first line treatment for moderate to severe inflammatory acne.

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.

Challenges and Solutions in Oral Isotretinoin in Acne: Reflections on 35 Years of Experience

Acne vulgaris affects more than 80% of adolescents and young adults and forms a substantial proportion of the dermatologist's and general practitioner's caseload. Severity of symptoms varies but may result in facial scarring and psychological repercussions. Oral isotretinoin is highly effective but can only be prescribed by specialists. Side effects are recognized and mostly predictable, ranging from cosmetic effects to teratogenicity. These can affect patients' quality of life and treatment adherence. This article provides a commentary on 4 key areas: the use of oral isotretinoin vs oral antibiotics, including the importance of early recognition of nonresponse to treatment, the psychological effects of acne and isotretinoin treatment, the side effects of isotretinoin therapy, and cosmetic treatment options that can help alleviate predictable side effects. The authors, who have all participated in various international expert groups, draw on relevant literature and their extensive professional experience with oral isotretinoin in the treatment of acne. The aim of this article is to provide an informative and practical approach to managing oral isotretinoin treatment in patients with acne, to help optimize treatment of this skin disease.

Risk of suicide attempt associated with isotretinoin: a nationwide cohort and nested case-time-control study

Background

Isotretinoin is the only effective treatment for severe acne. An isotretinoin-related suicide risk is still debated and under scrutiny by regulatory agencies. Our objectives were: to assess the risk of suicide attempt before, during and after isotretinoin treatment; to detect any potential triggering effect of isotretinoin initiation on suicide attempt.

Methods

We implemented a cohort and nested case-time-control study of subjects treated with oral isotretinoin (course or initiation) aged 10–50 years, using the Nationwide French Health Insurance data (2009–2016). The main outcome was hospitalized suicide attempt. Standardized incidence ratios for hospitalized suicide attempts were calculated before, during and after isotretinoin treatment. The number of isotretinoin initiations was compared in risk and control periods of 2 months using a case-time-control analysis.

Results

In all, 443 814 patients (median age 20.0 years; interquartile range 17.0–27.0 years) were exposed to isotretinoin, amounting to 244 154 person-years, with a marked seasonality for treatment initiation. Compared with the French general population, the occurrence of suicide attempts under isotretinoin treatment was markedly lower, with a standardized incidence ratio of 0.6 [95% confidence interval (CI) = 0.53–0.67]; the same applied, to a lesser extent, before and after isotretinoin treatment. In the case-time-control analysis, among cases of suicide attempt, 108 and 127 isotretinoin initiations were observed in the risk and control periods respectively (i.e. 0–2 months and 2–4 months before the date of suicide attempt). The comparison with the 1199 and 1253 initiations observed among matched controls in the same two periods yielded a case-time-control odds ratio of 0.89 (95% CI = 0.68–1.16). A sensitivity analysis using three-month periods and a complementary analysis adding completed suicides for case definition showed consistent results.

Conclusion

Compared with the general population, a lower risk of suicide attempt was observed among patients exposed to isotretinoin and there was no evidence for a triggering effect of isotretinoin initiation on suicide attempt. A selection of patients at lower risk for suicidal behaviour and appropriate treatment management could explain these findings. Risk management plans should therefore be maintained.

Acne Treatment With Light Absorbing Gold Microparticles and Optical Pulses: An Open-Label European Multi-Centered Study in Moderate to Moderately Severe Acne Vulgaris Patients

BACKGROUND AND OBJECTIVE

Recently, a novel acne treatment based on selective photothermolysis of pilosebaceous units with follicular delivery of inert gold microparticles as an exogenous chromophore and diode laser pulses has been developed. To evaluate the efficacy and safety of a single monotherapy treatment regimen with gold microparticles and diode laser exposure in patients with moderate and moderately severe acne. Further, to evaluate the added benefit of a second treatment regimen combined with pharmaceutical acne treatment in patients with inadequate initial response.

MATERIALS AND METHODS

Patients with moderate and moderately severe facial acne were recruited in this open-label, pilot study. A single treatment regimen consisted of three weekly facial treatments with topically applied gold microparticles and diode laser pulses. Outcome measures were the proportion of patients with ≥40% improvement in number of acne lesions (weighted lesion count [WLC]) at 12 weeks (single treatment regimen, primary outcome measure), 24, and 36 weeks from baseline (two treatment regimens), safety, and patient satisfaction.

RESULTS

A total of 28 patients were enrolled in the study (18 males, 10 females, 19 patients with moderate acne severity, 9 with moderately severe, mean age: 19.8 years). Twenty-five patients underwent analysis for outcome measures. After a single monotherapy treatment regimen, 76% patients (19/25) achieved ≥40% reduction in WLC (mean WLC reduction: 63%; SD: 13%). Of the patients undergoing two treatment regimens (n = 9 patients), 56% experienced a reduction in acne lesion burden (WLC) ≥40% at 24 weeks and 89% 36 weeks post-baseline. Mean pain score was 4.0 (SD: 1.3), and transient erythema and perifollicular edema were commonly noted after treatment. Most patients (81%) were either "satisfied" or "very satisfied" with the treatment.

CONCLUSION

Acne therapy based on selective photothermolysis with gold microparticles shows promise and may be used in treatment of moderate to moderately severe acne. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

p53: key conductor of all anti-acne therapies

This review based on translational research predicts that the transcription factor p53 is the key effector of all anti-acne therapies. All-trans retinoic acid (ATRA) and isotretinoin (13-cis retinoic acid) enhance p53 expression. Tetracyclines and macrolides via inhibiting p450 enzymes attenuate ATRA degradation, thereby increase p53. Benzoyl peroxide and hydrogen peroxide elicit oxidative stress, which upregulates p53. Azelaic acid leads to mitochondrial damage associated with increased release of reactive oxygen species inducing p53. p53 inhibits the expression of androgen receptor and IGF-1 receptor, and induces the expression of IGF binding protein 3. p53 induces FoxO1, FoxO3, p21 and sestrin 1, sestrin 2, and tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), the key inducer of isotretinoin-mediated sebocyte apoptosis explaining isotretinoin's sebum-suppressive effect. Anti-androgens attenuate the expression of miRNA-125b, a key negative regulator of p53. It can thus be concluded that all anti-acne therapies have a common mode of action, i.e., upregulation of the guardian of the genome p53. Immortalized p53-inactivated sebocyte cultures are unfortunate models for studying acne pathogenesis and treatment.

Network pharmacology-based approach of novel traditional Chinese medicine formula for treatment of acute skin inflammation in silico

Matrix metalloproteinase-9 (MMP-9) appears to play an important role in acute skin inflammation. Subantimicrobial dose of tetracycline has been demonstrated to inhibit the activity of MMP-9 protein. However, long-term use tetracycline will induce side effect. The catalytic site of MMP-9 is located at zinc-binding amino acids, His401, His405 and His411. We attempted to search novel medicine formula as MMP-9 inhibitors from traditional Chinese medicine (TCM) database by using in silico studies. We utilized high-throughput virtual screening to find which natural compounds could bind to the zinc-binding site. The quantitative structure-activity relationship (QSAR) models, which constructed by scaffold of MMP-9 inhibitors and its activities, were employed to predict the bio-activity of the natural compounds for MMP-9. The results showed that Celacinnine, Lobelanidine and Celallocinnine were qualified to interact with zinc-binding site and displayed well predictive activity. We found that celallocinnine was the best TCM compound for zinc binging sites of MMP-9 because the stable interactions were observed under dynamic condition. In addition, Celacinnine and Lobelanidine could interact with MMP-9 related protein that identified by drug-target interaction network analysis. Thus, we suggested the herbs Hypericum patulum, Sedum acre, and Tripterygium wilfordii that containing Celallocinnine, Celacinnine and Lobelanidine might be a novel medicine formula to avoid the side effect of tetracycline and increase the efficacy of treatment.

The age-old problem of acne

Acne vulgaris is one of the top three most commonly encountered dermatological problems worldwide in both primary and secondary care. Acne diagnosis and treatment date back to ancient Greek and Egyptian times. This article explores acne through the ages and discusses past theories on etiology and treatment with particular focus on the discovery of retinoids and their impact on women's health.

Pharmacological targeting of allergen-specific T lymphocytes

Allergic disorders are the result of a complex pathophysiology, involving major cellular lineages and a multitude of humoral factors of the innate and adaptive immune system, and have the tendency to involve multiple organs. Consequently, even standard pharmacological treatment of allergies is rarely specific but usually targets more than one pathway/cellular system at a time. Accordingly, many of the classic anti-allergic drugs have a critical impact also on T helper cells, which are pivotal not only during the sensitization but also the maintenance phase of allergic diseases. Recent years have seen a dramatic increase of novel drugs with the potency to interfere, more or less specifically, with T lymphocyte function, which might, possibly together with classic anti-allergic drugs, help harnessing one of the central cellular players in allergic responses. A major theme in the years to come will be a thoughtful combination of previously established with recently developed treatment modalities.

Ex vivo all-trans retinoic acid modulates NO production and regulates IL-6 effect during rheumatoid arthritis: a study in Algerian patients

Rheumatoid arthritis (RA) is a chronic autoimmune disease. The pathophysiology of RA implicates several mediators such as nitric oxide (NO) and cytokines such as interleukin-6 (IL-6), which is deeply involved in the main characteristics of RA. Furthermore, all-trans retinoic acid (ATRA) is an active vitamin A derivative well-known to have diverse immunomodulatory actions. In our study, we investigated first, the ex vivo immunomodulatory potential of ATRA on NO pathway by peripheral blood mononuclear cells (PBMCs) from Algerian RA patients. Then, we assessed the possible regulatory effect of ATRA on NO production induced by IL-6. PBMCs isolated from active and inactive RA patients and healthy controls were cultured with different concentrations of IL-6 or/with ATRA. NO production was assessed using the Griess method. Inducible nitric oxide synthase expression and NF-κB activity were analyzed by immunofluorescence test. Our results revealed a high NO production during active RA. We noticed that while IL-6 induced a high NO production and iNOS expression, ATRA downregulated both. ATRA also inhibited nuclear NF-κB translocation. Interestingly, it seems that NO production mediated by IL-6 on PBMCs of RA patients is downregulated by ATRA. Taken together, our results highlight the immunomodulatory effect of ATRA on NO pathway in RA patients and its possible role in regulating IL-6-mediated NO production. All these findings suggest its potential therapeutic role during RA.

Consensus-Based Acne Classification System and Treatment Algorithm for Spain

Acne is a chronic inflammatory disease whose psychosocial effects can greatly impair quality of life. Various scales are used to classify the severity of acne, and several treatment algorithms are currently applied: no consensus on a common scale or treatment guidelines has been reached. A group of Spanish experts therefore met to identify a scale the majority could accept as the most appropriate for classifying severity and treating accordingly. The group chose the following classifications: comedonal acne, mild or moderate papulopustular acne, severe papulopustular acne, moderate nodular acne, and nodular-cystic acne (or acne tending to leave scars). Consensus was reached on first- and second-choice treatments for each type and on maintenance treatment. The experts also issued specific recommendations on antibiotic use (starting with mild or moderate papulopustular acne), always in combination with retinoids and/or benzoyl peroxide. The use of isotretinoin (starting at severe papulopustular or moderate nodular acne) was also covered.

Does exposure to isotretinoin increase the risk for the development of inflammatory bowel disease? A meta-analysis

BACKGROUND

Isotretinoin is a treatment option for severe nodulocystic acne. However, its use has inconsistently been associated with the development of inflammatory bowel disease (IBD). This meta-analysis aims to elucidate the association between isotretinoin exposure and the risk for IBD.

METHODS

A comprehensive search of PubMed/MEDLINE, CINAHL, the Cochrane database, and Google Scholar was performed (July 2015). All studies on the development of IBD in patients with or without prior exposure to isotretinoin, along with control participants, were included. Meta-analysis was carried out using the Mantel-Haenszel random effect model to assess the risk for IBD in the context of prior isotretinoin exposure.

RESULTS

In a pooled analysis of six research studies, there was no increased risk of developing IBD in patients exposed to isotretinoin compared with patients not exposed to isotretinoin [odds ratio (OR) 1.08, 95% confidence interval (CI) 0.82, 1.42, P=0.59]. Furthermore, there was no increased risk of developing Crohn's disease (OR 0.98, 95% CI 0.62, 1.55, P=0.93, I(2)=62%) or ulcerative colitis (OR 1.14, 95% CI 0.79, 1.63, P=0.49, I(2)=44%) in patients exposed to isotretinoin compared with those not exposed to the medication.

CONCLUSION

Isotretinoin exposure is not associated with an increased risk of developing both ulcerative colitis and Crohn's disease.

A randomized comparative trial of two low-dose oral isotretinoin regimens in moderate to severe acne vulgaris

Background:

Oral isotretinoin is highly effective in all forms and grades of acne, even in lower dosages (<0.5 mg/kg/day). There is a paucity of comparative data on the various low-dose regimens of oral isotretinoin in the Indian literature.

Objectives:

To assess and compare the efficacy and tolerability of two low-dose oral isotretinoin treatment regimens (20 mg daily and 20 mg alternate days) in moderate to severe acne vulgaris.

Materials and Methods:

A total of 240 patients with moderate to severe acne vulgaris were selected and randomized into two groups and treated with a fixed dose of 20 mg of isotretinoin (Group A - daily and Group B - alternate days) for 24 weeks and followed up for 12 weeks post therapy.

Results:

A total of 234 patients completed the study. At the end of therapy, decrease in the total acne loads up to 98.99% (Group A) and 97.69% (Group B) was achieved from the baseline (P < 0.01), excellent response was observed in 98.3% (Group A) and 93.96% (Group B) patients (P = 0.166). In the severe acne, Group A performed significantly better than Group B until the end of 36 weeks. While in the moderate acne, significant difference in the response between both groups was observed only up to 12 weeks. No serious side effect was observed.

Conclusion:

Both isotretinoin regimens were well tolerated and found to be an effective treatment for moderate to severe acne vulgaris. However, in moderate acne 20 mg alternate day regimen may be preferred. A 20 mg daily regimen is a better choice for severe acne in terms of response.

Limitation:

Small sample size and short follow-up period.

Medicinal Plants for the Treatment of Acne Vulgaris: A Review of Recent Evidences

Context:

Acne vulgaris affects about 85% of teenagers and may continue to adulthood. There are about two million visits to physicians per year for teenagers and the direct cost of acne treatment in the US exceeds $1 billion per year.

Evidence Acquisition:

A wide variety of treatment regimens exist for acne vulgaris including benzoil peroxide, retinoids, isotretinoids, keratolytic soaps, alpha hydroxy acids, azelaic acid, salicilic acid as well as hormonal, anti-androgen or antiseborrheic treatments. However, none of these methods is free of side effects and their exact role in therapy is not clear. In this paper apart from presenting the possible causes of acne vulgaris and its available drugs, recently published papers about medicinal plants used in the treatment of acne vulgaris were reviewed.

Results:

Consumption of alternative and complementary medicine, including medicinal plants, is increasing and is common amongst patients affected by acne and infectious skin diseases. Medicinal plants have a long history of use and have been shown to possess low side effects. These plants are a reliable source for preparation of new drugs.

Conclusions:

Many plants seem to have inhibitory effects on the growth of bacteria, fungi and viruses in vitro. However, there are a few clinical evidences about the effectiveness and safety of these plants in the treatment of acne and other skin infections.

Retinoids and rexinoids in cancer prevention: from laboratory to clinic

Early in the age of modern medicine the consequences of vitamin A deficiency drew attention to the fundamental link between retinoid-dependent homeostatic regulation and malignant hyperproliferative diseases. The term "retinoid" includes a handful of endogenous and a large group of synthetic derivatives of vitamin A. These multifunctional lipid-soluble compounds directly regulate target genes of specific biological functions and critical signaling pathways to orchestrate complex functions from vision to development, metabolism, and inflammation. Many of the retinoid activities on the cellular level have been well characterized and translated to the regulation of processes like differentiation and cell death, which play critical roles in the outcome of malignant transformation of tissues. In fact, retinoid-based differentiation therapy of acute promyelocytic leukemia was one of the first successful examples of molecularly targeted treatment strategies. The selectivity, high receptor binding affinity and the ability of retinoids to directly modulate gene expression programs present a distinct pharmacological opportunity for cancer treatment and prevention. However, to fully exploit their potential, the adverse effects of retinoids must be averted. In this review we provide an overview of the biology of retinoid (activated by nuclear retinoic acid receptors [RARs]) and rexinoid (engaged by nuclear retinoid X receptors [RXRs]) action concluded from a long line of preclinical studies, in relation to normal and transformed states of cells. We will also discuss the past and current uses of retinoids in the treatment of malignancies, the potential of rexinoids in the cancer prevention setting, both as single agents and in combinations.

Evaluation of Evidence for Acne Remission With Oral Isotretinoin Cumulative Dosing of 120-150 mg/kg

Background:

Oral isotretinoin (ISO) is the standard of care for severe inflammatory acne and a threshold dose of 120-150 mg/kg is widely regarded as increasing remission potential.

Objective:

Our objective was to evaluate the evidence underlying ISO dosing of 120-150 mg/kg in acne remission.

Methods:

A systematic literature search was performed using keywords “acne,” “isotretinoin,” “efficacy,” “dosing,” “relapse,” and “remission.”

Results:

Definitions for acne clearance, relapse/remission, and treatment endpoint vary widely across studies. Only 2 studies explicitly evaluated the cumulative dose of 120-150 mg/kg for induction of acne remission—both low grade.

Conclusion:

The threshold dose of 120-150 mg/kg for oral ISO is based on past parameters of treatment duration and prior studies used vague or inconsistent definitions of clearance and remission. Optimal cumulative doses of ISO required to induce remission appears to vary with severity.

Acne Treatment Based on Selective Photothermolysis of Sebaceous Follicles with Topically Delivered Light-Absorbing Gold Microparticles

The pathophysiology of acne vulgaris depends on active sebaceous glands, implying that selective destruction of sebaceous glands could be an effective treatment. We hypothesized that light-absorbing microparticles could be delivered into sebaceous glands, enabling local injury by optical pulses. A suspension of topically applied gold-coated silica microparticles exhibiting plasmon resonance with strong absorption at 800 nm was delivered into human pre-auricular and swine sebaceous glands in vivo, using mechanical vibration. After exposure to 10-50 J cm(-2), 30 milliseconds, 800 nm diode laser pulses, microscopy revealed preferential thermal injury to sebaceous follicles and glands, consistent with predictions from a computational model. Inflammation was mild; gold particles were not retained in swine skin 1 month after treatment, and uptake in other organs was negligible. Two independent prospective randomized controlled clinical trials were performed for treatment of moderate-to-severe facial acne, using unblinded and blinded assessments of disease severity. Each trial showed clinically and statistically significant improvement of inflammatory acne following three treatments given 1-2 weeks apart. In Trial 2, inflammatory lesions were significantly reduced at 12 weeks (P=0.015) and 16 weeks (P=0.04) compared with sham treatments. Optical microparticles enable selective photothermolysis of sebaceous glands. This appears to be a well-tolerated, effective treatment for acne vulgaris.

Retinoid receptors in bone and their role in bone remodeling

Vitamin A (retinol) is a necessary and important constituent of the body which is provided by food intake of retinyl esters and carotenoids. Vitamin A is known best for being important for vision, but in addition to the eye, vitamin A is necessary in numerous other organs in the body, including the skeleton. Vitamin A is converted to an active compound, all-trans-retinoic acid (ATRA), which is responsible for most of its biological actions. ATRA binds to intracellular nuclear receptors called retinoic acid receptors (RARα, RARβ, RARγ). RARs and closely related retinoid X receptors (RXRα, RXRβ, RXRγ) form heterodimers which bind to DNA and function as ligand-activated transcription factors. It has been known for many years that hypervitaminosis A promotes skeleton fragility by increasing osteoclast formation and decreasing cortical bone mass. Some epidemiological studies have suggested that increased intake of vitamin A and increased serum levels of retinoids may decrease bone mineral density and increase fracture rate, but the literature on this is not conclusive. The current review summarizes how vitamin A is taken up by the intestine, metabolized, stored in the liver, and processed to ATRA. ATRA's effects on formation and activity of osteoclasts and osteoblasts are outlined, and a summary of clinical data pertaining to vitamin A and bone is presented.

In vivo long-term effects of retinoic acid exposure in utero on induced tumours in adult mouse skin

BACKGROUND

Retinoic acid (RA) and its analogues (retinoids) are promising agents in skin cancer prevention following either topical application or oral administration. However, long-term in vivo effects of RA on chemically induced hyperplastic epidermal foci in adult mouse skin have also been described, casting some doubt with regard to its chemopreventive activity.

HYPOTHESIS/OBJECTIVES

To characterize chemically induced skin tumours and to investigate the in vivo long-term action and preventive effect of RA on adult mouse skin carcinogenesis.

ANIMALS

Fifty-six adult Naval Medical Research Institute mice, exposed (n = 28) or not exposed (n = 28) to RA in utero.

METHODS

Mice were treated with a standard two-stage skin carcinogenesis protocol, which included an initiating application of 7,12-dimethylbenz(a)anthracene followed by promotion with 12-O-tetradecanoylphorbol 13-acetate.

RESULTS

Retinoic acid administered to pregnant mice showed a long-term inhibitory action on cell differentiation and development of chemically induced tumours on the adult skin of their offspring, as well as a stimulatory effect on cell proliferation and expression of an early marker of malignant progression (keratin 13).

CONCLUSIONS AND CLINICAL IMPORTANCE

The results suggest that RA exposure in utero confers long-lasting effects on adult mouse skin carcinogenesis. These include chemopreventive activity (reduced number of tumours), as well as enhancement of squamous papilloma progression, which appears to be due to enhanced keratinocyte proliferation and suppression of epidermal maturation. The clinical significance of these findings is not known for other routes of RA administration at this time.

Safety and efficacy of low-dose isotretinoin in the treatment of moderate to severe acne vulgaris

Background:

Isotretinoin is indicated for moderate to severe cases of acne which are unresponsive to conventional therapy. The classical recommended dose is 0.5 to 1.0 mg/kg/day. As the side effects are dose related, low-dose isotretinoin therapy for acne is an attractive option; however, but little data exists on the safety and efficacy of this strategy.

Materials and Methods:

In this prospective, non-comparative study, 50 participants, both male and female, having moderate to severe acne vulgaris were enrolled and treated with isotretinoin at a dose of 20 mg/day (approximately 0.3-0.4 mg/kg/day), for a period of 3 months. Participants were evaluated by means of clinical and laboratory investigations before starting isotretinoin. Investigations were repeated at the end of the first and third months following completion of treatment, and participants were followed up for 6 months to look for any relapse.

Results:

At the end of the treatment, very good results were observed in 90% of participants. Cheilitis was the most common among the side effects observed and was seen in 98% of the participants. One participant developed vitiligo as a side effect, which is a new finding, and has not reported in literature before. Elevated serum lipid levels were observed in 6% of the participants, and relapse occurred in 4% of the participants over a 6 month follow up period.

Conclusion:

Three months of treatment with low-dose isotretinoin (20 mg/day) was found to be effective in the treatment of moderate to severe acne vulgaris, with a low incidence of serious side effects. This dose also was more economical than the higher doses.

Isotretinoin updates

Acne vulgaris is a chronic inflammatory disease of pilosebaceous follicles commonly affecting adolescents and young adults. This disease has a profound psychological impact on affected individuals and treatment has been shown to significantly improve both self-esteem and quality of life. Isotretinoin is an effective medication used primarily in severe cystic acne patients. Over the past 30 years, this medication has revolutionized the treatment of acne. However, despite its popularity there are numerous side effects associated with its use. Most of its side effects are predictable and dose dependent, which has led to the development of variable dose regimens. Unfortunately, rare but significant side effects (e.g., depression, inflammatory bowel disease) do occur and necessitate careful monitoring to improve clinical outcomes and minimize potential adverse events.

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.

Vitamin a metabolism, action, and role in skeletal homeostasis

Vitamin A (retinol) is ingested as either retinyl esters or carotenoids and metabolized to active compounds such as 11-cis-retinal, which is important for vision, and all-trans-retinoic acid, which is the primary mediator of biological actions of vitamin A. All-trans-retinoic acid binds to retinoic acid receptors (RARs), which heterodimerize with retinoid X receptors. RAR-retinoid X receptor heterodimers function as transcription factors, binding RAR-responsive elements in promoters of different genes. Numerous cellular functions, including bone cell functions, are mediated by vitamin A; however, it has long been recognized that increased levels of vitamin A can have deleterious effects on bone, resulting in increased skeletal fragility. Bone mass is dependent on the balance between bone resorption and bone formation. A decrease in bone mass may be caused by either an excess of resorption or decreased bone formation. Early studies indicated that the primary skeletal effect of vitamin A was to increase bone resorption, but later studies have shown that vitamin A can not only stimulate the formation of bone-resorbing osteoclasts but also inhibit their formation. Effects of vitamin A on bone formation have not been studied in as great a detail and are not as well characterized as effects on bone resorption. Several epidemiological studies have shown an association between vitamin A, decreased bone mass, and osteoporotic fractures, but the data are not conclusive because other studies have found no associations, and some studies have suggested that vitamin A primarily promotes skeletal health. In this presentation, we have summarized how vitamin A is absorbed and metabolized and how it functions intracellularly. Vitamin A deficiency and excess are introduced, and detailed descriptions of clinical and preclinical studies of the effects of vitamin A on the skeleton are presented.

Systemic treatment of severe forms of acne: experience of using Isotretinoin in the Russian Federation

The article presents the results of a large-scale Russian program of the follow-up and treatment of acne patients with Isotretinoin (Roaccutane). The analysis of the results included information about 1,349 acne patients. In 71% of patients, the therapy was initiated at the dose of 0.5-1.0 mg/kg of the body weight. The average duration of treatment was 21.5±0.16 weeks while the average course dose was 119.9±0.8 mg/kg of the body weight. As many as 96% of patients achieved a positive result; women demonstrated a higher improvement rate than men. On the whole, Roaccutane was well-tolerated while adverse effects included dry lips (43.4%), dry skin in different areas (12.45%), retinoid dermatitis (6.45%), epistaxis (2.45%), conjunctivitis (1.41%) and hoarseness (0.22%). The Russian experience of using Roaccutane confirmed high efficacy of the systemic therapy for severe forms of acne.

Isotretinoin oil-based capsule formulation optimization

The purpose of this study was to develop and optimize an isotretinoin oil-based capsule with specific dissolution pattern. A three-factor-constrained mixture design was used to prepare the systemic model formulations. The independent factors were the components of oil-based capsule including beeswax (X₁), hydrogenated coconut oil (X₂), and soybean oil (X₃). The drug release percentages at 10, 30, 60, and 90 min were selected as responses. The effect of formulation factors including that on responses was inspected by using response surface methodology (RSM). Multiple-response optimization was performed to search for the appropriate formulation with specific release pattern. It was found that the interaction effect of these formulation factors (X₁X₂, X₁X₃, and X₂X₃) showed more potential influence than that of the main factors (X₁, X₂, and X₃). An optimal predicted formulation with Y_10 min, Y_30 min, Y_60 min, and Y_90 min release values of 12.3%, 36.7%, 73.6%, and 92.7% at X₁, X₂, and X₃ of 5.75, 15.37, and 78.88, respectively, was developed. The new formulation was prepared and performed by the dissolution test. The similarity factor f₂ was 54.8, indicating that the dissolution pattern of the new optimized formulation showed equivalence to the predicted profile.