Acne. An overview of clinical research findings

Extracts from Cephalaria Uralensis (Murray) Roem. & Schult. and Cephalaria Gigantea (Ledeb.) Bobrov as Potential Agents for Treatment of Acne Vulgaris: Chemical Characterization and In Vitro Biological Evaluation

The aim of this study was to compare the chemical composition, as well as antioxidant, anti-inflammatory, antiacne, and cytotoxic activites of various extracts of Cephalaria gigantea and C. uralensis. It is worth underlining that we are the first to characterize the composition and evaluate the biological properties of extracts from Cephalaria gigantea and C. uralensis. Thus, the LC-DAD-MS3 analysis revealed the presence of 41 natural products in studied extracts. The 5-O-caffeoylquinic acid, isoorinetin, and swertiajaponin were the main detected compounds. Among the tested samples, ethanol extract of the aerial parts of C. uralensis (CUE) possessed the most suitable biological properties. It exhibited moderate ability to scavenge free radicals and good capacity to inhibit cyclooxygenase-1, as well as cyclooxygenase-2. Moreover, CUE possessed moderate antibacterial activity against all tested bacterial strains (S. aureus, S. epidermidis, and P. acnes), and importantly, it was non-toxic towards normal skin fibroblasts. Taking into account the value of calculated therapeutic index (>10), it is worth noting that CUE can be subjected to in vivo study. Thus, CUE constitutes a very promising antiacne agent.

Daily Intake of Soft Drinks and Moderate-to-Severe Acne Vulgaris in Chinese Adolescents

OBJECTIVES

To investigate the association of soft drink consumption and the intake of sugar from soft drinks with the prevalence of acne in adolescents.

STUDY DESIGN

This was a university-based epidemiologic investigation that included 8226 students who underwent health examinations and a questionnaire survey inquiring about the intake of soft drinks. Skin diseases were diagnosed by certificated dermatologists during the health examination. Two-level logistic and generalized additive models were used to estimate the associations, and aORs were presented as the effect size.

RESULTS

A total of 8197 student survey responses were analyzed. Frequent intake (≥7 times per week) of carbonated sodas (aOR 1.61, 95% CI 0.96-2.72), sweetened tea drinks (aOR 2.52, 95% CI 1.43-4.43), and fruit-flavored drinks (aOR 1.90, 95% CI 1.18-3.07) was associated with moderate-to-severe acne after adjustments for confounders. The occasional intake of fruit-flavored drinks (1-2 times per week) had a weak protective effect on acne (aOR 0.86, 95% CI 0.74-0.99). The intake of sugar from any soft drinks showed a nonlinear association with acne (P < .01), and sugar intake ≥100 g/d was significantly associated with moderate-to-severe acne (aOR 3.12, 95% CI 1.80-5.41).

CONCLUSIONS

Daily soft drink consumption significantly increases the risk of moderate-to-severe acne in adolescents, especially when the sugar intake from any type of soft drink exceeds 100 g per day.

A Review of Antibiotics in Dermatology

Background:

Since the early 1930s when antibiotics were first introduced, they have revolutionized the way physicians treat infections. Skin conditions from acne to leprosy, which were once shunned by society, are now easily treated with oral antibiotics.

Objective:

Antibiotics are chemicals derived from bacteria and fungi that uniquely have antibacterial action. The most notable example is penicillin, which is derived from a mold. With hundreds of antibiotics available to the practicing physician, improper use of these drugs has become widespread and expensive and has spawned resistant strains. For the dermatologist, antibiotics are vital weapons in the drug armamentarium for treating various skin conditions.

Conclusion:

This review explores the newest and most common oral, parenteral, and topical antibiotics used in dermatology, their indications, adverse effects, dosage, and spectrum of activity. Furthermore, systemic antibacterial prophylaxis and vaccines pertinent to dermatology are discussed. The penicillins, cephalosporins, tetracyclines, macrolides, fluoroquinolones, sulfonamides, aminoglycosides, lincosamides, folate inhibitors, and a new synthetic class of drugs, the oxazolidinones, are reviewed. These antibiotics are used to treat a variety of organisms.

A randomized controlled study for the treatment of acne vulgaris using high-intensity 414 nm solid state diode arrays

The treatment of acne vulgaris poses a challenge to the dermatologist, and the disease causes emotional anxiety for the patient. The treatment of acne vulgaris may be well-suited to home-use applications, where sufferers may be too embarrassed to seek medical treatment. This randomized controlled study is designed to quantify the effectiveness of using a blue light device in a therapy combined with proprietary creams, in the investigation of a self-treatment regimen. A total of 41 adults with mild-to-moderate facial inflammatory acne were recruited. The subjects were randomly assigned to combination blue light therapy (n = 26) or control (n = 15). Photography was used for qualitative assessment of lesion counts, at weeks 1, 2, 4, 8, and 12. All subjects in the treatment cohort achieved a reduction in their inflammatory lesion counts after 12 weeks. The mean inflammatory lesion counts reduced by 50.02% in the treatment cohort, and increased by 2.45% in the control cohort. The reduction in inflammatory lesions was typically observable at week-3, and maximal between weeks 8 and 12. The treatment is free of pain and side-effects. The blue light device offers a valuable alternative to antibiotics and potentially irritating topical treatments. Blue light phototherapy, using a narrow-band LED light source, appears to be a safe and effective additional therapy for mild to moderate acne.

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.

The protective effects of melittin on Propionibacterium acnes-induced inflammatory responses in vitro and in vivo

Melittin is the main component in the venom of the honey bee (Apis mellifera). It has multiple effects including antibacterial, antiviral, and anti-inflammatory activities in various cell types. However, the anti-inflammatory mechanisms of melittin have not been elucidated in Propionibactierium acnes (P. acnes)-induced keratinocyte or inflammatory skin disease animal models. In this study, we examined the effects of melittin on the production of inflammatory cytokines in heat-killed P. acnes-induced HaCaT cells. Heat-killed P. acnes-treated keratinocytes increased the expression of pro-inflammatory cytokines and Toll-like receptor 2. However, melittin treatment significantly suppressed the expression of these cytokines through regulation of the NF-κB and MAPK signaling pathways. Subsequently, the living P. acnes (1 × 10(7) CFU) were intradermally injected into the ear of mice. Living P. acnes-injected ears showed cutaneous erythema, swelling, and granulomatous response at 24 hours after injection. However, melittin-treated ears showed markedly reduced swelling and granulomatous responses compared with ears injected with only living P. acnes. These results demonstrate the feasibility of applying melittin for the prevention of inflammatory skin diseases induced by P. acnes.

The clinical impact and cost-effectiveness of essential oils and aromatherapy for the treatment of acne vulgaris: a protocol for a randomized controlled trial

BACKGROUND

Acne is a prevalent, chronic, and sometimes severe skin disorder affecting an estimated 85% of adolescents and 50% of adults older than age 20 years. The psychosocial implications of acne can be considerable, often continuing long after physical symptoms resolve. Although effective acne medications are available, most exhibit adverse-effect profiles that can leave the patient with few effective treatment options. Emerging evidence indicates that plant-derived essential oils may be a biologically plausible treatment for acne, although high-quality evidence of effectiveness and safety is lacking.

OBJECTIVE

To examine the clinical effectiveness and cost-effectiveness of essential oils and aromatherapy for the treatment of acne.

DESIGN

This randomized, wait-list controlled trial will have three parallel groups; 192 participants with acne vulgaris, aged 16-45 years, will be recruited primarily through eight Technical and Further Education campuses across Adelaide, South Australia. Participants will be randomly assigned to standard essential oil blend, customized aromatherapy treatment, or wait-list control. Changes in the physical and psychosocial symptoms of acne will be assessed at baseline and 6 and 12 weeks by using the Leeds Acne Grading System, Assessment of Quality of Life-8 Dimension instrument, and Acne-Specific Quality of Life instrument. Costs of treatment will be measured on the basis of resource inputs and unit costs and will be limited to acne treatment. The clinical effectiveness and cost-effectiveness will be compared between each intervention and against usual care, using standard health economic techniques.

CONCLUSIONS

The provision of high-quality evidence of the effectiveness of essential oils and aromatherapy in the treatment of acne may help consumers make better-informed choices about acne management. Insights gained from this research will also contribute to the academic field of complementary medicine, specifically aromatherapy, for which the evidence base is extremely limited.

Acne: prevalence and relationship with dietary habits in Eskisehir, Turkey

BACKGROUND

Acne vulgaris is a common disease affecting adolescents. There is not comprehensive data on acne prevalence in the Central Anatolia Region in particular. Etiology of acne is not clarified yet. Acne might be related to environmental factors. There is increasing evidence supporting acne and diet relationship.

OBJECTIVES

The aim of the study was to determine the acne prevalence in adolescents in the city of Eskisehir, located in the Central Anatolia, Turkey in addition to evaluate factors affecting acne and its relationship with dietary habits.

METHODS

A cross-sectional study was conducted on 2300 participants aged 13-18 years. The participants were asked to complete a questionnaire form consisting information about acne and a questionnaire form consisting information about dietary habits (The Adolescent Food Habits Checklist). In addition an objective evaluation of acne was determined.

RESULTS

The mean age of students with acne was 15.10±1.53. The current acne prevalence was 60.7%. Although 21% of the participants had severe acne (grade 3-4) and 25% developed sequelaes, only 11.5% of all participants consulted a doctor. The participants without acne had healthier dietary habits than participants with acne (P<0.05). Frequent fat intake (OR=1.39, 95% CI: 1.06-1.82), frequent sugar intake (OR=1.30, 95% CI: 1.05-1.60), frequent eating sausages, burgers (OR=1.24, 95% CI: 1.03-1.48), frequent eating pastries, cakes (OR=1.20, 95% CI: 1.01-1.43) were associated with increased risk for acne.

CONCLUSIONS

Acne prevalence is high among adolescents in Eskisehir but the rate of consulting doctor is low. Increasing public awareness is critical for convincing adolescents to seek medical help earlier. Acne was related with dietary habits. Fat, sugar and fast food consumption is found to be positively correlated with acne prevalence.

Anti-inflammatory effects of active constituents extracted from Chinese medicinal herbs against Propionibacterium acnes

Interleukin-8 (IL-8) and tumour necrosis factor-alpha (TNF-α) from keratinocyte play important roles in initiating the inflammatory process of acne. They are used as major elements to evaluate the anti-inflammatory activity of drugs. In this study, various active constituents extracted from Chinese medicinal herbs were tested for their anti-inflammatory effects against P. acnes using ELISA. Among the constituents, matrine, baicalin, ursolic acid, sodium danshensu, magnolol, honokiol, hesperidin and andrographolide significantly reduced IL-8 and TNF-α by human HaCaT keratinocyte cells pretreated with heat-killed P. acnes. Excepting hesperidin, these active constituents presented dose-dependent inhibitory effects. Our studies showed that all of them exhibited low cytotoxicity at 5 µg mL⁻¹ in tested cell lines, and even at 50 µg mL⁻¹, in the cases of matrine, baicalin, ursolic acid and sodium danshensu. Based on the obtained results, it can be suggested that these active constituents are potential acne-mitigating candidates for cosmetic applications.

Effect of insulin-like growth factor-1 deficiency or administration on the occurrence of acne

BACKGROUND

The role of growth hormone, insulin, and insulin-like growth factor-1 (IGF-1) in the development of acne is incompletely understood.

OBJECTIVE

To study the effect of the absence of IGF-1 and its pharmacologic replacement on the occurrence of acne vulgaris.

PATIENTS AND METHODS

Laron syndrome (LS) is characterized by congenital IGF-1 deficiency. The study group consisted of 21 patients with classical LS, who underwent puberty: 13 (8 male, 5 female) untreated and under regular follow-up until age 20?48 years; and 8 (2 male, 6 female) treated with IGF-1 (70-200 μg/kg/day), including 6 adults (2 male, treated at age 14.5-29 years and 4 female, treated at age 30-37 years) and 2 adolescents (2 female, treated at age 3.5-16 years). The medical files were reviewed for occurrence of acne and the corresponding sex hormone levels, and the findings were compared between the treated and untreated patients.

RESULTS

Puberty was delayed in all untreated patients. Only one patient had slight acne at age 22 years, when he reached full puberty. Among the 2 IGF-1 treated male patients, none acquired acne. Among the 6 treated female patients, 3 had signs of hyperandrogenism (oligo-amenorrhea) and acne during IGF-1 over-dosage. On reduction of the IGF-1 dose (to 50 μg/kg/day) or cessation of treatment, the acne disappeared in all 3 patients.

CONCLUSION

This study demonstrates for the first time that serum IGF-1 deficiency prevents the occurrence of acne. The findings suggest that an interaction between IGF-1 and androgens is necessary for the development of acne.

Propionibacterium acnes activates the IGF-1/IGF-1R system in the epidermis and induces keratinocyte proliferation

Propionibacterium acnes has a major role in the development of acne lesions. IGF-1 stimulates the proliferation of keratinocytes via an activation of the IGF-1 receptor (IGF-1R). Zinc has been proven to work efficiently against inflammatory acne and to modulate the IGF-1 system. Our objectives were to study the modulation of IGF-1 and IGF-1R expression by P. acnes extracts and to determine their modulation by zinc gluconate. In vivo, we analyzed biopsies of acne lesions and healthy skin, and in vitro we used skin explants incubated with two P. acnes extracts--membrane fraction (MF) and cytosolic proteins--with or without zinc. IGF-1 and IGF-1R expression was evaluated using immunohistochemistry, and the IGF-1 production in supernatants was measured by ELISA. Then, IGF-1 and IGF-1R mRNA levels were analyzed using quantitative PCR on normal human epidermal keratinocytes (NHEKs). IGF-1 and IGF-1R were overexpressed in acne lesions. MF increased IGF-1 and IGF-1R expression in the epidermis of explants and was associated with an overexpression of both Ki-67 and filaggrin. Zinc had the effect of downregulating IGF-1 and IGF-1R levels. These observations were confirmed at the mRNA level for IGF-1R in NHEKs. These results demonstrate that P. acnes can induce the formation of comedones by stimulating the IGF/IGF-1R system. Moreover, zinc downregulates this pathway.

Physicians underutilize topical retinoids in the management of acne vulgaris: analysis of U.S. National Practice Data

BACKGROUND

Topical retinoids are effective in the treatment of acne, yet no current guidelines existed in the literature until recently recommending their use as an integral part of mild to moderate acne treatment.

OBJECTIVE

To assess whether underutilization of topical retinoids occurs in clinical practice.

DESIGN

Weighted data on representative office visits with acne vulgaris diagnoses were analyzed using the National Ambulatory Medical Care Survey (NAMCS), from 1990 to 1999.

RESULTS

Of the 54.2 million acne vulgaris visits, retinoids were prescribed at 35.3% visits. Dermatologists prescribed significantly more retinoids than non-dermatologists (39.4%' versus 23%). Dermatology visit was a significant predictor of topical retinoid prescription (RR: 2.27,95% CI: 1.63-3.17). Data suggest that prescribing retinoids for acne has been increasing over the past decade, primarily among dermatologists.

CONCLUSION

There is a major difference between suggested treatment guidelines for acne and actual practice in the community. There is distinct under-utilization of topical retinoids for treatment of acne vulgaris by dermatologists and non-dermatologists.

Antimicrobial activity of enterocins from Enterococcus faecalis SL-5 against Propionibacterium acnes, the causative agent in acne vulgaris, and its therapeutic effect

A lactic acid bacterial strain was isolated from human fecal specimen and identified as Enterococcus faecalis SL-5. The isolated strain showed antimicrobial activity against Gram-positive pathogens assayed, especially the highest activity against Propionibacterium acnes. The antimicrobial substance was purified and verified as a bacteriocin (named ESL5) of E. faecalis SL-5 by activity-staining using P. acnes as an indicator. N-terminal sequence of ESL5 was determined (MGAIAKLVAK) and sequence analysis revealed that it is almost identical to the some of enterocins including L50A/B of E. faecium L50 and MR10A/B of E. faecalis MRR 10-3. From the sequencing data of L50A/B structural genes, the nucleotide sequence showed 100% identity with that of the MR10A/B structural genes, implying that ESL5 is an equivalent of enterocin MR10. Meanwhile, we also tested the therapeutic effect of anti-P. acnes activity in patients with mild to moderate acne because of its pathogenic role to acne vulgaris. For this purpose, a concentrated powder of CBT SL-5 was prepared using cell-free culture supernatant (CFCS) of E. faecalis SL-5 and included in a lotion for application in the patients. The study showed that CBT SL-5 lotion significantly reduced the inflammatory lesions like pustules compared to the placebo lotion. Therefore our results indicate that the anti-P. acnes activity produced by E. faecalis SL-5 has potential role to the treatment of acne as an alternative to topical antibiotics.

Characterisation of cryptic plasmid pPG01 from Propionibacterium granulosum, the first plasmid to be isolated from a member of the cutaneous propionibacteria

A cryptic plasmid, pPG01 (3539bp), was isolated from Propionibacterium granulosum and sequenced. Analysis of open reading frames (ORFs) predicted pPG01 to encode three proteins. The largest protein (447 amino acids) showed homology to the FtsK/SpoIIIE family of proteins involved in chromosome partitioning during cell division and conjugal transfer of DNA. A second protein of 433 amino acids showed homology to plasmid replication proteins that mediate replication by the rolling circle mechanism. A third protein of 124 amino acids had no predicted function. All three ORFs were expressed as shown by reverse transcription-PCR analysis. Putative double- and single-stranded origins of replication were identified. Rolling circle replication of pPG01 was confirmed by the detection of single-stranded DNA intermediates. The first characterisation of a plasmid from the cutaneous propionibacteria may lead to development of a vector system to enable the genetic manipulation of this important group of organisms.

Genome sequence and analysis of a Propionibacterium acnes bacteriophage

Cutaneous propionibacteria are important commensals of human skin and are implicated in a wide range of opportunistic infections. Propionibacterium acnes is also associated with inflammatory acne vulgaris. Bacteriophage PA6 is the first phage of P. acnes to be sequenced and demonstrates a high degree of similarity to many mycobacteriophages both morphologically and genetically. PA6 possesses an icosahedreal head and long noncontractile tail characteristic of the Siphoviridae. The overall genome organization of PA6 resembled that of the temperate mycobacteriophages, although the genome was much smaller, 29,739 bp (48 predicted genes), compared to, for example, 50,550 bp (86 predicted genes) for the Bxb1 genome. PA6 infected only P. acnes and produced clear plaques with turbid centers, but it lacked any obvious genes for lysogeny. The host range of PA6 was restricted to P. acnes, but the phage was able to infect and lyse all P. acnes isolates tested. Sequencing of the PA6 genome makes an important contribution to the study of phage evolution and propionibacterial genetics.

420 nm intense continuous light therapy for acne

BACKGROUND

Topical antibiotics, isotretinoin or systemic antibiotics are usually used for acne therapy. However, isotretinoin cannot be used during pregnancy because it can cause significant birth defects while systemic antibiotics can have adverse side effects such as gastrointestinal irritation, photosensitivity and tetracycline sensitivity. Describe here is a high-intensity, narrow-band, blue light (ClearLight) system, and its therapeutic clinical effect is investigated on acne using cutaneous measurements, bacterial observations and ultrastructural changes.

MATERIALS AND METHODS

A total of 28 adult healthy volunteers with facial acne (mean age 28.1 years, range 16-56 years) were recruited for this study. They were treated with a total of eight serial biweekly 15-minute treatment sessions. Clinical counts of acne, as well as moisture, sebum and pH measurements were taken between each session. Nine of the 28 patients were followed for 2-3 months after the last treatment. Detection of bacteria in acne pustules was analyzed by culture and by polymerase chain reaction (PCR). Ultrastructural changes were examined in eight patients after four sessions of the light therapy.

RESULTS

All patients completed the study. Overall, there was a 64.7% improvement in acne lesions. There were no bacterial changes before or after the therapy, although damaged Propionibacterium acnes were observed at the ultrastructural level.

CONCLUSIONS

ClearLight performed eight times over 4 weeks can be useful in the treatment of acne. Further investigation will be needed to elucidate the mechanism of action of ClearLight.

Acne: inflammation

The inflammatory stage of acne vulgaris is usually of greatest concern to the patient. A number of morphologically different inflammatory lesions may form that can be painful and unsightly. In 30% of patients, such lesions lead to scarring(1). Inflammatory acne and acne scarring can have significant psychological effects on the patient, including depression, anxiety, and poor self-image(2). Although inflammatory acne has been well characterized clinically, the mechanisms by which inflammatory lesions arise are still poorly understood. The human skin commensal bacterium, Propionibacterium acnes, has long been associated with inflammatory acne. This organism has been implicated over and above all of the other cutaneous microflora in contributing to the inflammatory response characteristic of acne. However, its precise role in the disease and its interaction with the human immune system remain to be elucidated.

Acne and diet

Forbidden foods? "The first law of dietetics seems to be: If it tastes good, it's bad for you" (Isaac Asimov, Russian-born biochemist and science fiction writer). This was essentially the Magna Carta for dermatologists of the 1950s: anything coveted by the teenage palate was suspect for morning after acne. Today, half a century later, although the slant has shifted away for this line of thinking in our dermatologic textbooks, several articles on the beliefs and perceptions of acne patients showed that nothing much has changed and that they expect us to give them detailed instructions of what "acne-related" foods they should avoid. In one such study(1), diet was the third most frequently implicated factor (after hormones and genetics) as the cause of the disease, with 32% of the respondents selecting diet as the main cause, and 44% thinking that foods aggravate acne. In another study that analyzed knowledge about causes of acne among English teenagers, 11% of the responders blamed greasy food as the main cause of the disease(2), whereas in another study found that 41% of final-year medical students of the University of Melbourne chose diet as an important factor of acne exacerbation on a final examination.(3)

Oral contraceptives as anti-androgenic treatment of acne

Although acne is seldom associated with high serum levels of androgens, it has been shown that female acne patients have definite increases in ovarian and adrenal androgen levels when compared to appropriate controls. As shown in several pilot and in multiple open and comparative studies, oral contraceptives (OCs) are effective in causing a significant regression of mild to moderate acne. These results have been confirmed by multicentre randomized trials where low-dose OCs did not cause side effects different from those of the placebo-controlled group. The beneficial effect of OCs is related to a decrease in ovarian and adrenal androgen precursors; to an increase in sex hormone-binding globulin (SHBG), which limits free testosterone; and to a decrease in 3a-androstenediol glucuronide conjugate, the catabolite of dihydrotestosterone (DHT) formed in peripheral tissues. The estrogen-progestin combination containing cyproterone acetate (CPA) is particularly effective in treating acne, since this progestin also has a direct peripheral anti-androgenic action in blocking the androgen receptor. Only two open studies and one randomized study on small numbers of patients have reported some efficacy of spironolactone used alone or in combination with an OC in the treatment of acne. The new non-steroidal anti-androgens flutamide and finasteride are being evaluated for the treatment of hirsutism. Oral antibiotics are prescribed to patients with inflammatory lesions, where they are effective in decreasing the activity of microbes, the activity of microbial enzymes, and leukocyte chemotaxis. Concomitant intake of an OC and an antibiotic usually prescribed for acne does not impair the contraceptive efficacy of the OC. A second effective contraceptive method should be used whenever there would be decreased absorption or efficacy of the OC (digestive problems, breakthrough bleeding), lack of compliance and use of a type or dose of antibiotic different from that usually prescribed for acne.Overall, the various approaches for the treatment of acne depend on the needs of the patient and on the therapeutic objectives. Low-dose OCs are effective in improving acne and have side effects similar to placebo. They can be used alone or in combination with other anti-acne agents. The physician prescribing an OC as an anti-androgen intervention should take into account the multiple factors involved in acne and be familiar with current non-hormonal agents for treating mild to moderate acne. Individuals presenting with moderate to severe acne, or not responding to an estrogen-progestin combination, should be referred to a dermatologist.

A review of antibiotics in dermatology

BACKGROUND

Since the early 1930s when antibiotics were first introduced, they have revolutionized the way physicians treat infections. Skin conditions from acne to leprosy, which were once shunned by society, are now easily treated with oral antibiotics.

OBJECTIVE

Antibiotics are chemicals derived from bacteria and fungi that uniquely have antibacterial action. The most notable example is penicillin, which is derived from a mold. With hundreds of antibiotics available to the practicing physician, improper use of these drugs has become widespread and expensive and has spawned resistant strains. For the dermatologist, antibiotics are vital weapons in the drug armamentarium for treating various skin conditions.

CONCLUSION

This review explores the newest and most common oral, parenteral, and topical antibiotics used in dermatology, their indications, adverse effects, dosage, and spectrum of activity. Furthermore, systemic antibacterial prophylaxis and vaccines pertinent to dermatology are discussed. The penicillins, cephalosporins, tetracyclines, macrolides, fluoroquinolones, sulfonamides, aminoglycosides, lincosamides, folate inhibitors, and a new synthetic class of drugs, the oxazolidinones, are reviewed. These antibiotics are used to treat a variety of organisms.

Safety issues in isotretinoin therapy

Isotretinoin (Accutane, Roche Laboratories Inc, Nutley, NJ) is an important drug, not only for the treatment of severe acne, but also for other diagnoses and in chemoprevention settings. Because the use of isotretinoin is increasing, it is important for physicians to be aware of the adverse events, toxicities, and management issues related to its use. The most important issue is that of congenital defects, which has resulted in new pregnancy prevention policies and programs implemented by the manufacturer. A relatively new concern is that of depression associated with isotretinoin use, also resulting in new policies placed by the manufacturer and the FDA. The most common adverse effects observed during treatment are mucocutaneous and ocular in nature, but laboratory abnormalities and effects in the nervous, musculoskeletal, gastrointestinal, pulmonary, hematologic, and other systems are also described. Additionally, potential drug interactions, follow-up, and toxicity prevention measures are discussed.

Heat shock proteins and inflammatory acne vulgaris: molecular cloning, overexpression and purification of a propionibacterium acnes GroEL and DnaK homologue

Propionibacterium acnes is associated with inflammatory acne. The genes encoding two putative mediators of inflammation, the heat shock proteins GroEL and DnaK, were cloned from this organism and sequenced. groEL and dnaK encode proteins of 56.8 and 66.4 kDa, respectively, which show a high degree of homology (>75% similarity) to the GroEL and DnaK proteins of mycobacteria and streptomycetes. The promoter regions of both genes contain inverted repeat sequences believed to be involved in the transcriptional regulation of heat shock genes. Recombinant P. acnes GroEL and DnaK were overexpressed in Escherichia coli with C-terminal histidine tags. The recombinant proteins were purified from E. coli by metal affinity chromatography. These proteins will now be used in immunological investigations to determine their role in inflammatory acne.

Effect of low-dose oral contraceptives on androgenic markers and acne

Oral contraceptives (OC) suppress excess androgen production; however, different progestins in combination with low-dose estrogens produce divergent effects on sex hormone-binding globulin (SHBG) and testosterone that may influence clinical outcomes. This multicenter, open-label, randomized study compared biochemical androgen profiles and clinical outcomes associated with two OC containing the same amounts of ethinyl estradiol (EE, 20 micrograms) but different progestins, levonorgestrel (LNG, 100 micrograms), and norethindrone acetate (NETA, 1000 micrograms). Fifty-eight healthy women (18-28 years old) received three cycles of treatment with LNG/EE (n = 30) or NETA/EE (n = 28). The results showed that LNG reduced androgen levels in three compartments--adrenal, ovarian, and peripheral. NETA reduced only adrenal and peripheral androgens. Despite a 2.2-fold greater relative increase in SHBG with NETA than LNG, bioavailable testosterone (T) was reduced by the same amount with LNG and NETA. Both treatments improved acne and were well tolerated. Low-dose OC (EE, 20 micrograms) are effective in reducing circulating androgens and acne lesions without causing weight gain. Although LNG and NETA affected secondary markers differently, both OC formulations produced an equivalent decrease in bioavailable.

Novel retinoids with receptor selectivity and functional selectivity

Retinoids mediate a number of physiological pathways through their effects on cellular growth and differentiation. Upon binding to retinoic acid receptors (RARs) and retinoid X receptors (RXRs), retinoids regulate cellular processes by directly modulating the expression of responsive genes. The wide-ranging effects of retinoid action are attributable to two main factors-the ubiquitous distribution of several subtypes and isoforms of RARs and RXRs, and the ability of these receptors to regulate numerous genes upon ligand activation. The broad range of effects mediated by retinoids means not only that they have many potential therapeutic applications but also that non-selective retinoids are associated with a high incidence of adverse effects. The design of retinoids that are receptor-selective and function-selective is a strategy that is proving successful in developing novel retinoids that offer not only good efficacy but also good tolerability. Tazarotene, a receptor-selective retinoid indicated for the topical treatment of psoriasis, is at the forefront of this new generation of retinoids. In the near future, other receptor-selective retinoids may prove useful for the treatment of other dermatological diseases, cancer, and diabetes.

Future trends: a new generation of retinoids

The existence of several different types of retinoid receptors, response elements, and cofactors means that retinoid physiology is mediated by multiple discrete pathways and is highly complex. As a result, non-selective retinoids have a multitude of physiologic effects and are usually associated with toxicity problems that limit their therapeutic usefulness. In contrast, because receptor-selective retinoids have a more focused and targeted action, they are likely to have a better therapeutic index. Tazarotene is the first of a new generation of receptor-selective retinoids. Its actions are targeted on 2 retinoic acid receptors (RARs), RAR-beta and RAR-gamma. Current retinoid research is leading to the development not only of many more novel receptor-selective retinoids but also of novel types of function-selective retinoids such as RAR inverse agonists and RAR antagonists. These retinoids are expected to be of clinical benefit not only in dermatology but also in oncology, diabetes, and diseases associated with the human papilloma virus.