Regulation of lipid production by acetylcholine signalling in human sebaceous glands

Assessment of current practices and perceived effectiveness of injectable polynucleotide for enlarged facial pores among cosmetic physicians: A survey-based evaluation

BACKGROUND

Polynucleotides stimulate collagen formation and are used clinically to enhance elasticity. In this study, we investigated current practices and perceived effectiveness of polynucleotide injection treatment for enlarged facial pores among cosmetic physicians.

MATERIALS AND METHODS

A survey was developed to investigate clinicians' use and effectiveness of polynucleotides in the treatment of enlarged facial pores. This survey was distributed to clinicians at the Korean Aesthetic Surgery & Laser Society Autumn Symposium.

RESULTS

A total of 407 physicians who used polynucleotides for enlarged facial pores were enrolled in the survey. Polynucleotides were used by 75.7%, 87.7%, and 72.2% of physicians for enlarged facial pores caused by excessive sebum production, reduced elasticity, and acne, respectively. Among those users, 81.4%, 83.8%, and 76.8% in those same categories, respectively, responded that polynucleotides were "very effective" or "effective." Furthermore, most clinicians combined polynucleotides with microneedle radiofrequency as energy-based devices and with botulinum toxin as injection therapy.

CONCLUSION

This study highlights the widespread use and perceived efficacy of polynucleotide injection among cosmetic physicians in the Republic of Korea for enlarged facial pores due to excessive sebum production, reduced elasticity, and acne. Positive feedback from practitioners supports the benefits of using polynucleotides in enlarged facial pore treatment.

Using Neuromodulators to Improve Scar Formation, Keloids, Rosacea, and Antiaging

BACKGROUND

Botulinum toxin A (BoNT-A) treatment has many uses in dermatology. Its mechanism of action and long-term effects for scar formation, rosacea, and antiaging are still being investigated.

OBJECTIVE

To conduct a literature review on BoNT-A to further investigate its use in scar formation, rosacea, and antiaging.

METHODS

A literature review was conducted using PubMed on botulinum toxin treatment for scar formation, rosacea, and antiaging. Studies discussing the toxin mechanism of action and treatment algorithm were included. The authors also provided their personal experience in BoNT-A use for these 3 conditions.

RESULTS

The mechanism of action of Botulinum toxin A in improving scar formation, rosacea, and antiaging is now better understood. While it is effective in the short term, little is still known about how frequently treatment needs to be repeated and if there are any long-term effects.

CONCLUSION

While in vitro studies have supporting evidence on the mechanism of action of BoNT-A on scar formation, rosacea, and antiaging, further studies are needed to identify long-term treatment effects.

Intradermal Botulinum Toxin A on Skin Quality and Facial Rejuvenation: A Systematic Review and Meta-analysis

Background

Botulinum toxin A (BTxA) has gained popularity as a nonsurgical aesthetic treatment for skin rejuvenation. However, previous studies on intradermal BTxA have shown inconsistent results. This systematic review and meta-analysis with trial sequential analysis aimed to assess the efficacy and safety of intradermal BTxA for facial rejuvenation.

Methods

Following PRISMA guidelines, a comprehensive search was conducted in various databases from January 2008 to March 2023. Outcome measures included sebum production, pore size, skin hydration, skin texture, erythema index, facial wrinkles, and facelift. Eligible studies included human-based clinical trials and prospective cohort studies published in English, focusing on healthy populations requiring facial rejuvenation. Two authors independently screened the titles and abstracts, followed by a full-text review to determine study eligibility. Data extraction and quality assessment were performed by two authors using predefined criteria.

Results

Ten studies met the inclusion criteria, including five randomized controlled trials and five prospective cohort studies with 153 participants. Studies revealed positive effects of intradermal BTxA on various outcome measures related to facial rejuvenation. These effects included improvements in sebum production, pore size, erythema index, facial wrinkles, skin texture and elasticity, and overall facelift but not skin hydration. All failed to reach the required information size in the trial sequential analysis.

Conclusions

Findings suggest positive outcomes in multiple attributes of skin quality and facial rejuvenation. However, more high-quality research is needed to establish definitive conclusions. These findings contribute to the evidence base for nonsurgical aesthetic treatments, emphasizing the importance of ongoing research in this field.

The role of botulinum neurotoxin BoNT-A in the management of oily skin and acne vulgaris: A comprehensive review

Oily skin and acne vulgaris are prevalent dermatological conditions with a significant impact on both physical and emotional well-being. Despite numerous available treatments, there is a pressing need for effective, long-term solutions. Botulinum Neurotoxin (BoNT-A) has emerged as a potential therapeutic option. However, existing reviews in this area are often limited. This review aims to comprehensively assess the use of BoNT-A in managing oily skin and acne vulgaris while addressing gaps in previous publications. It integrates the latest research, clinical trials, and case studies to provide an up-to-date analysis of BoNT-A mechanisms of action, efficacy, safety, and long-term outcomes. The review systematically analyzes existing evidence, critically evaluates study strengths and limitations, and explores potential synergies with other treatments. It also examines the safety profile of BoNT-A and its potential long-term effects. This review uncovers promising insights into how BoNT-A affects oily skin and acne vulgaris, including its ability to regulate sebum production, reduce inflammation, and potentially shrink pore size. It provides a comprehensive overview of relevant studies and clinical trials, detailing their methodologies, protocols, measures, and results. Collectively, these studies show significant reductions in sebum production, increased patient satisfaction, and smaller pores following BoNT-A treatment. In conclusion, this review addresses knowledge gaps and provides a comprehensive analysis of BoNT-A as a therapeutic option for oily skin and acne vulgaris. By consolidating evidence and highlighting areas for further investigation, it guides clinicians and researchers toward more effective, personalized treatments for individuals with these dermatological challenges.

Promoting New Approach Methodologies (NAMs) for research on skin color changes in response to environmental stress factors: tobacco and air pollution

Aging is one of the most dynamic biological processes in the human body and is known to carry significant impacts on individuals' self-esteem. Skin pigmentation is a highly heritable trait made possible by complex, strictly controlled cellular and molecular mechanisms. Genetic, environmental and endocrine factors contribute to the modulation of melanin's amount, type and distribution in the skin layers. One of the hallmarks of extrinsic skin aging induced by environmental stress factors is the alteration of the constitutive pigmentation pattern clinically defined as senile lentigines and/or melasma or other pigmentary dyschromias. The complexity of pollutants and tobacco smoke as environmental stress factors warrants a thorough understanding of the mechanisms by which they impact skin pigmentation through repeated and long-term exposure. Pre-clinical and clinical studies demonstrated that pollutants are known to induce reactive oxygen species (ROS) or inflammatory events that lead directly or indirectly to skin hyperpigmentation. Another mechanistic direction is provided by Aryl hydrocarbon Receptors (AhR) which were shown to mediate processes leading to skin hyperpigmentation in response to pollutants by regulation of melanogenic enzymes and transcription factors involved in melanin biosynthesis pathway. In this context, we will discuss a diverse range of New Approach Methodologies (NAMs) capable to provide mechanistic insights of the cellular and molecular pathways involved in the action of environmental stress factors on skin pigmentation and to support the design of raw ingredients and formulations intended to counter their impact and of any subsequently needed clinical studies.

AbobotulinumtoxinA improves skin properties and sebum quality in the rhino mouse

Besides neuronal cells, botulinum neurotoxins (BoNTs) can also affect other cell types such as fibroblasts or keratinocytes. These cells play a key role in skin conditions. Maintaining a high-quality sebum secretion is essential to avoid premature aging. This study explored the effect of abobotulinumtoxinA (aboBoNT-A) in the rhino mouse. Briefly, anaesthetized animals were injected via the intra-dermal route (ID; four sites of injection) by either vehicle or 0.1, 0.3 and 1 Unit aboBoNT-A per mouse. A reference group was administered with adapalene gel 0.1% (daily local application) for 15 days. Adapalene is a third-generation retinoid and is used as first-line treatment of moderate acne. The body weight and the thickness of the dorsal skin were measured on days 1, 5, 10 and 15; erythema and scaling were recorded at the same time. On day 15, animals were ethically euthanized and skin samples were collected for histology, ELISA and lipidomic assays. AboBoNT-A administered ID at the doses 0.1 U and 0.3 U per mouse was well tolerated. 1 U aboBoNT-A (per mouse) induced a transient loss of muscle tone associated with a slight body weight loss after which mice recovered a good health status. AboBoNT-A did not show any significant effect on utricles surface area but induced a significant anti-inflammatory effect on dermis at the two highest doses. Moreover, aboBoNT-A showed neither side effects commonly observed with local retinoids, nor hyperplasia or dermis inflammation. No change in skin Interleukin-1alpha (IL-1α) cytokine levels was evidenced with aboBoNT-A, whereas a dose-dependent increase of substance P (SP) concentration in the skin was recorded, suggesting that aboBoNT-A induces neuropeptide accumulation in tissue by inhibiting exocytosis mechanisms. Lipidomic analysis showed that aboBoNT-A significantly increased the sebum concentration of several lipid species, presenting skin protecting properties. Overall, these data suggest that ID aboBoNT-A has skin rejuvenation, anti-inflammatory and moisture-boosting properties.

Exploring the Pathogenesis and Mechanism-Targeted Treatments of Rosacea: Previous Understanding and Updates

Rosacea is a chronic inflammatory skin disease characterized by recurrent erythema, flushing, telangiectasia, papules, pustules, and phymatous changes in the central area of the face. Patients with this condition often experience a significant negative impact on their quality of life, self-esteem, and overall well-being. Despite its prevalence, the pathogenesis of rosacea is not yet fully understood. Recent research advances are reshaping our understanding of the underlying mechanisms of rosacea, and treatment options based on the pathophysiological perspective hold promise to improve patient outcomes and reduce incidence. In this comprehensive review, we investigate the pathogenesis of rosacea in depth, with a focus on emerging and novel mechanisms, and provide an up-to-date overview of therapeutic strategies that target the diverse pathogenic mechanisms of rosacea. Lastly, we discuss potential future research directions aimed at enhancing our understanding of the condition and developing effective treatments.

Unparallel improvement patterns of dynamic wrinkles and skin quality after botulinum toxin type A treatment on the upper face

BACKGROUND

Botulinum toxin type A (BoNT-A) can not only reduce the dynamic wrinkles but also improve the skin quality. This study aims to quantitaively and comprehensively assess the improvement of dynamic wrinkles and skin quality following BoNT-A treatment on the upper face.

METHODS

Patients were recruited to receive BoNT-A treatment of the glabellar, frontal, and lateral periorbital wrinkles. Antera 3D camera was used to evaluate the skin quality and dynamic wrinkle severity. Follow-up visits were at 1 week, 1 month, 3 months, and 6 months after treatment. Different filters were utilized to quantitatively detect the severity of fine wrinkles (FWS), the volume of pores (PV), the roughness of skin texture (STR), and the severity of dynamic wrinkles (DWS).

RESULTS

Twenty-four participants (average 30.5 ± 7.2 years) were recruited. The significant improvement of PV, FWS, and STR in different areas usually maintained from 1 to 6 months after injections but of DWS only existed within 3 months. For each area, the improvement rates of FWS, PV, and STR peaked at 3 months or 6 months after treatment while the maximal improvement of DWS was observed at 1 month posttreatment.

CONCLUSION

After BoNT-A treatment for dynamic wrinkles on the upper face, the skin quality of target regions can also be ameliorated. The improvement of skin quality and dynamic wrinkles presented unparallel patterns. The former is with a slower onset but longer duration while the latter exhibits a more rapid onset but shorter duration.

Inhibition of lipogenesis and sebum secretion for Lotus corniculatus seed extract in vitro and in vivo

BACKGROUND

Botanical ingredients are widely used in hair- and skin-care products. However, few studies have investigated the effectiveness of botanical products on counteracting sebum synthesis and secretion.

OBJECTIVE

To investigate the composition of Lotus corniculatus seed extract (LC) and its potential inhibition of lipogenesis in SZ95 sebocytes and oily human skin.

METHODS

The active components of LC solutions were identified by high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR). The in vitro effects of LC were evaluated using SZ95 cells treated with linoleic acid (LA) and dihydrotestosterone (DHT) and incubated with LCs for 24 h and 72 h. Lipogenesis was assessed by Oil Red O and Nile Red staining of the cells. In vivo effects were assessed on 30 subjects with oily skin who were enrolled in a randomized, blank-controlled trial and were treated with LC solution for 6 h and 4 weeks. The skin sebum contents and area on the forehead and cheeks were evaluated using a Sebumeter SM815 and Sebfix sebutape with Visioscan VC98. In addition, VISIA was used to collect half-face photos for analysis.

RESULTS

A novel active molecule, 5'-o-rhamnosyl uridine, was identified in LC. LC exhibited a dose-dependent inhibitory effect on LA and DHT-induced lipid synthesis. When 5% LC was applied for 3 h, the skin sebum contents and area were significantly reduced compared with the vehicle control, with an obvious reduction after 6 h. Continued use of the serum containing 5% LC for 4 weeks resulted in a significant reduction in the skin sebum contents and area. No adverse reactions were reported during the study.

CONCLUSIONS

Topical application of LC resulted in an immediate and long-lasting reduction of the sebum contents and area of oily human skin by reducing sebaceous lipogenesis through the LA and DHT pathways. This indicates the potential of LC as a new biological treatment for oily skin.

Microbotox injection versus its topical application following microneedling in the treatment of wide facial pores: A split face comparative study

BACKGROUND

Enlarged facial pores and seborrhea are common cosmetic problems. Mesobotox has been proved to be effective safe therapeutic option.

OBJECTIVE

To compare the efficacy and longevity of intradermal mesobotox injection versus its topical application with microneedling for treatment of wide facial pores and seborrhea.

MATERIALS AND METHODS

This split face study was conducted on 20 patients with enlarged facial pores and seborrhea. One side of the face was treated with intradermal injection of botulinum toxin, the other was treated with its topical application following microneedling. Patient evaluation was performed after 1 month then after 4 months.

CONCLUSION

Microbotox can effectively and safely minimize enlarged facial pores with no downtime. Intradermal injection showed more patient satisfaction on the basis of greater efficacy, longevity of treatment than its topical application following microneedling.

Long‐pulsed Nd: YAG laser (1064 nm) versus intralesional botulinum toxin type (A) in acne vulgaris therapy: a split face study

BACKGROUND

Acne can be considered more than a cosmetic concern due to its large impact on patients' quality of life. There are various therapeutic options for inflammatory acne, but inconvenience and undesirable side effects prompted a search for more acceptable treatments. This study aimed to compare the clinical efficacy and safety of long-pulsed Nd: YAG laser 1064 nm versus intralesional botulinum toxin type-A (BTX-A) in inflammatory acne therapy.

METHODS

A prospective randomized split-face comparative study involved 30 patients with inflammatory acne. Each patient received long-pulsed Nd: YAG 1064 nm laser on one side, and intralesional BTX-A on the other side, monthly until improvement or maximum three sessions. Cases were assessed by acne lesions counting and grading of severity by Investigator's Global Assessment of acne (IGAs) at baseline, each session, and after 3 months follow-up.

RESULTS

A highly statistically significant improvement in lesions count and IGAs for both sides was observed, with statistically non-significant difference between both sides at end of treatment sessions. While, after 3 months follow-up, there was a more significant improvement at laser side.

CONCLUSION

Both long-pulsed Nd: YAG laser 1064 nm and intralesional BTX-A are safe and effective for acne therapy. Nd-YAG laser has a more prolonged efficacy and lower recurrence rate than intralesional BTX-A.

A Double-Blind, Split-Face, Randomized Study on the Effects and Safety of Intradermal Injection of Botulinum Toxin A (Incobotulinum Toxin A) in the Cheek

BACKGROUND

Intradermal injection of botulinum toxin A (BTXA) is used for cosmetic purposes without strong evidence for clinical use, as opposed to intramuscular injection.

OBJECTIVE

To evaluate the efficacy and safety of intradermal injection of incobotulinum toxin A (iBTXA) in the cheeks.

METHODS

We conducted a study with 18 volunteers who received intradermal injection of iBTXA into one cheek and normal saline into the contralateral side as a control. Volunteers visited the clinic at weeks 2, 4, 8, and 12 after injection. At each visit, pores and wrinkles were evaluated by a facial analyzer, sebum secretion by a sebumeter, skin texture by both volunteers and clinicians, and wrinkles of the nasolabial fold were graded with photographic reviews.

RESULTS

There were no significant effects on the wrinkles of the infraorbital area and sebum secretion. However, there were significant improvements in the wrinkles of the nasolabial fold and skin texture on the iBTXA injected side. The effects on the wrinkles of the nasolabial fold lasted 12 weeks, and those on skin texture lasted 8 weeks. Improvement in the pore size was observed only at week 2. No serious adverse events were reported except one volunteer who complained of facial palsy after the injection of 30 units of iBTXA in one cheek. However, injection of 20 units of iBTXA in one cheek was not associated with any adverse events.

CONCLUSION

Intradermal injection of iBTXA, could provide clinical benefits for skin texture and wrinkles overcoming the skin prick effect without obvious side effects.

Botulinum Neurotoxin Type A Directly Affects Sebocytes and Modulates Oleic Acid-Induced Lipogenesis

Excess sebum (seborrhea) results in oily skin and is associated with large pore size and acne. Studies in healthy, seborrheic volunteers have reported that intradermal injection of commercial preparations of botulinum neurotoxin type A (BoNT/A) (onabotulinumtoxinA, abobotulinumtoxinA, and incobotulinumtoxinA) reduced sebum production, and thus, skin oiliness and pore size. The mechanism for these effects has not been fully elucidated; however, several theories involving direct or indirect effects of BoNT/A on neuronal and/or dermal cells (e.g., sebocytes) have been proposed. In the present study, we evaluated the direct effect of native research grade BoNT/A complex, a commercial preparation of BoNT/A (onabotA), and BoNT/A variants on sebocyte lipogenesis using an in vitro sebocyte cell model. We show that picomolar concentrations of BoNT/A (BoNT/A complex: half maximal effective concentration [EC₅₀] = 24 pM; BoNT/A 150 kDa: EC₅₀ = 34 pM) modulate sebocyte lipogenesis and reduce oleic acid-induced sebocyte differentiation, lipogenesis, and holocrine-like secretion. Comparative studies with the binding domain of BoNT/A, which lacks enzymatic activity, show that this effect is independent of the enzymatic activity of BoNT/A and likely occurs via sebocyte cell surface receptors (e.g., fibroblast growth factor receptors). Overall, these results shed light on the potential mechanism of action and rationale for use of BoNT/A for treatment of sebum-related conditions.

Intradermal Botulinum Toxin A Injection for Scalp Sebum Secretion Regulation: A Multicenter, Randomized, Double-Blinded, Placebo-Controlled, Prospective Study in Chinese Subjects

BACKGROUND

Although botulinum toxin type A (BTX-A) injection has been proved to reduce topical sebum secretion, the impact of intradermal BTX-A injection on scalp sebum production has never been reported.

OBJECTIVES

The purpose of this study was to investigate the efficacy and safety of intradermal BTX-A treatment vs intradermal normal saline (NS) injection for scalp sebum secretion regulation.

METHODS

This multicenter, randomized, double-blinded, prospective study recruited patients complaining of oily scalp and/or hair. The patients were randomly allocated to receive either 1 session of intradermal BTX-A or NS injection. The baseline and posttreatment scalp sebum secretion at 24, 48, 72, and 96 hours postshampooing was measured with a Sebumeter SM815 (Cutometer Dual MPA 580, Courage & Khazaka, Cologne, Germany) at 1, 3, 4, and 6 months after treatment. The patients' comments, satisfaction, and adverse events were evaluated and compared.

RESULTS

In total, 25 patients in the BTX-A group and 24 patients in the NS group completed the follow-up. For the treated region, compared with NS, intradermal BTX-A treatment (50-65 U) significantly reduced scalp sebum secretion at 24, 48, and 72 hours postshampooing at the 1- and 3-month follow-up visits (P < 0.05). No significant difference between the 2 groups was observed at 4 and 6 months after the treatment. The patients' satisfaction ratings were significantly higher for the BTX-A treatment (P = 0.000). No serious adverse events occurred.

CONCLUSIONS

Compared with NS, 1 session of intradermal BTX-A injection (50-65 U) effectively and safely reduced scalp sebum secretion and greasiness perception in the treated region at 24 and 48 hours postshampooing for 3 months.

LEVEL OF EVIDENCE: 4

The Effect of Synthetic Acetylhexapeptide-8 (AH8) on Sebaceous Function

OBJECTIVE

This study aims to evaluate the in vitro and clinical effects of topical acetylhexapeptide-8 (AH8) on the appearance of oily skin.

METHODS

In vitro SEB-1 human sebocyte cell lines were exposed to different concentrations of AH8 , then the lipid content of the sebocytes was measured. For the randomized, controlled, split-face clinical study, participants received AH8 10% lotion formulated in Cetaphil Moisturizing Facial Lotion on one side of their face and the control vehicle lotion on the other side of their face. Facial oiliness was assessed by a trained physician using a 3-point grading system, high-resolution digital photographs, and a sebumeter (SM815). Participants also filled out self-assessments of their skin oiliness.

RESULTS

The in vitro experiments showed that sebocyte lipid content significantly decreased after AH8 treatment (p < 0.05 at 0.00005% AH8 , p=0.09 at 0.0005% AH8 , p < 0.05 at 0.005% AH8,and p < 0.001 at 0.025% AH8). In the clinical study, participants trended towards a 10% reduction (p=0.16) in sebum production after AH8 treatment in comparison to the vehicle treatment.

CONCLUSION

AH8 inhibits the accumulation of lipids in sebocytes in vitro without altering cell proliferation or SREBP-1 expression. Topical AH8 trended toward decreased sebum production in human participants. The use of AH8 may serve as a promising agent to reduce sebocyte lipid production and the appearance of oily skin.

Toxicology and pharmacology of botulinum and tetanus neurotoxins: an update

Tetanus and botulinum neurotoxins cause the neuroparalytic syndromes of tetanus and botulism, respectively, by delivering inside different types of neurons, metalloproteases specifically cleaving the SNARE proteins that are essential for the release of neurotransmitters. Research on their mechanism of action is intensively carried out in order to devise improved therapies based on antibodies and chemical drugs. Recently, major results have been obtained with human monoclonal antibodies and with single chain antibodies that have allowed one to neutralize the metalloprotease activity of botulinum neurotoxin type A1 inside neurons. In addition, a method has been devised to induce a rapid molecular evolution of the metalloprotease domain of botulinum neurotoxin followed by selection driven to re-target the metalloprotease activity versus novel targets with respect to the SNARE proteins. At the same time, an intense and wide spectrum clinical research on novel therapeutics based on botulinum neurotoxins is carried out, which are also reviewed here.

The Air Toxin Technique: Introduction and Analysis of Effect using a Photo Imaging System

BACKGROUND

As an alternative to other approaches to facial rejuvenation, the air toxin technique (dermal injection of air with micro-doses of botulinum toxin) is a promising method. We aimed to describe this novel technique and assess the overall safety and efficacy of the air toxin technique in facial rejuvenation.

MATERIALS AND METHODS

A retrospective chart review was performed on cases treated with the air toxin technique. A total of 47 Korean patients underwent a single treatment session. Treatment efficacy was assessed objectively with serial VISIA® (Canfield Scientific, NJ, USA) skin analysis data and subjectively based on the patients' assessment scores at week 12.

RESULTS

A significant improvement in Wrinkle (p < 0.001), UV spot (p < 0.001), and Porphyrin (p = 0.005) were objectively seen at 12-weeks follow-up. Patients noted improvement in the categories Wrinkle (p < 0.01), Redness (p = 0.029), Texture (p < 0.001), Dilated pore (p < 0.001), and Lifting (p < 0.001) at week 12 compared to baseline. No major adverse event was reported.

CONCLUSIONS

Our data show that the Air toxin technique is efficacious in facial rejuvenation as shown by improved skin analysis parameters and patient assessment scores. Notably, there was some discrepancy between the objective and subjective parameters of improvement.

Coronary Heart Disease in Type 2 Diabetes Mellitus: Genetic Factors and Their Mechanisms, Gene-Gene, and Gene-Environment Interactions in the Asian Populations

Asians are more susceptible to type 2 diabetes mellitus (T2D) and its coronary heart disease (CHD) complications than the Western populations, possibly due to genetic factors, higher degrees of obesity, insulin resistance, and endothelial dysfunction that could occur even in healthy individuals. The genetic factors and their mechanisms, along with gene-gene and gene-environment interactions associated with CHD in T2D Asians, are yet to be explored. Therefore, the objectives of this paper were to review the current evidence of genetic factors for CHD, summarize the proposed mechanisms of these genes and how they may associate with CHD risk, and review the gene-gene and gene-environment interactions in T2D Asians with CHD. The genetic factors can be grouped according to their involvement in the energy and lipoprotein metabolism, vascular and endothelial pathology, antioxidation, cell cycle regulation, DNA damage repair, hormonal regulation of glucose metabolism, as well as cytoskeletal function and intracellular transport. Meanwhile, interactions between single nucleotide polymorphisms (SNPs) from different genes, SNPs within a single gene, and genetic interaction with environmental factors including obesity, smoking habit, and hyperlipidemia could modify the gene's effect on the disease risk. Collectively, these factors illustrate the complexities of CHD in T2D, specifically among Asians.

Microdroplet botulinum toxin: A review

Microbotox is the administration of multiple microdroplets of botulinum toxin in intradermal plane. It is increasingly becoming popular owing to its more favorable outcome and better safety profile than the conventional technique. The intention is to treat fine lines and wrinkles without imparting an undesired “frozen face like” appearance. Besides facial rejuvenation, it has found its way into the management of other indications such as rosacea, hyperhidrosis, keloid, and seborrhea. Being a relatively newer method, knowledge about the various dilution methods, desired volume, and correct depth of injection involved in this technique remain scarce. In this article, the authors have highlighted various indications, procedures, adverse effects, and contraindications of microbotox.

Botulinum Neurotoxin Type A in the Treatment of Facial Seborrhea and Acne: Evidence and a Proposed Mechanism

Intradermal injection of botulinum neurotoxin is a frequently performed procedure in aesthetic dermatology to improve facial skin tone, texture, fine wrinkles, and enlarged pores. In practice, botulinum neurotoxin type A is also used to reduce skin oiliness of the face. There is increasing evidence that acetylcholine plays specific roles in sebum production, suggesting that botulinum neurotoxin type A may reduce sebum production by interfering with cholinergic transmission between sebaceous glands and autonomic nerve terminals. Botulinum neurotoxins can also inhibit several pathogenetic components of acne development, suggesting that botulinum neurotoxins can be used as a safe and effective treatment modality for acne and other skin disorders related to overactivity of sebaceous glands. This review aims to explore the current evidence behind the treatment of facial seborrhea and acne with botulinum neurotoxin type A.

The skin microbiome and the gut-skin axis

The microbiome plays a significant role in human health, homeostasis, immune system, and disease pathogenesis. Disrupted communication between the microbiome and host has been extensively studied in gastrointestinal diseases. To a lesser extent, there is emerging research on the skin microbiome and its connection with the gut, referred to as the gut-skin axis and its effects on dermatologic conditions. A basic overview will be provided of the gut and skin microbiome with a focus on the impact of this connection on cutaneous diseases, such as psoriasis, atopic dermatitis, rosacea, acne vulgaris, photoaging, and cutaneous wounds. In addition, we shall discuss nutrition-based approaches mediated through the gut-skin axis and topical treatments that could serve as potential adjunctive management by manipulation of the microbiome. In particular, there is a growing body of research on oral probiotics, prebiotics, and dietary modifications that may help improve symptoms for a variety of dermatologic conditions in select demographic groups.

Utilities of Botulinum Toxins in Dermatology and Cosmetology

Botulinum toxin (BoNT) is a neurotoxin produced by the Clostridium botulinum bacterium with a well-known efficacy and safety profile in the focal idiopathic hyperhidrosis treatment. BoNT comprises seven different neurotoxins; however, only toxins A and B are clinically employed. BoNT is lately practiced in off-label therapies for a variety of skin diseases. Scar prevention, hyperhidrosis, rhytides, eccrine nevus, alopecia, psoriasis, Darier disease, bullous skin disease, pompholyx and Raynaud's phenomenon are some of the novel indications for BoNT in cosmetic and notably non-cosmetic aspects of dermatology. To employ BoNT correctly in clinical practice, we must have a thorough understanding of the functional anatomy of the mimetic muscles. An intensive literature search was conducted to update all dermatology-oriented experiments and clinical trials on the described element of BoNT for this general overview of BoNT use in dermatology. This review aims to analyse the role of BoNT in dermatology and cosmetology.

Non-invasive diagnostic tool for Parkinson's disease by sebum RNA profile with machine learning

Parkinson's disease (PD) is a progressive neurodegenerative disease presenting with motor and non-motor symptoms, including skin disorders (seborrheic dermatitis, bullous pemphigoid, and rosacea), skin pathological changes (decreased nerve endings and alpha-synuclein deposition), and metabolic changes of sebum. Recently, a transcriptome method using RNA in skin surface lipids (SSL-RNAs) which can be obtained non-invasively with an oil-blotting film was reported as a novel analytic method of sebum. Here we report transcriptome analyses using SSL-RNAs and the potential of these expression profiles with machine learning as diagnostic biomarkers for PD in double cohorts (PD [n = 15, 50], controls [n = 15, 50]). Differential expression analysis between the patients with PD and healthy controls identified more than 100 differentially expressed genes in the two cohorts. In each cohort, several genes related to oxidative phosphorylation were upregulated, and gene ontology analysis using differentially expressed genes revealed functional processes associated with PD. Furthermore, machine learning using the expression information obtained from the SSL-RNAs was able to efficiently discriminate patients with PD from healthy controls, with an area under the receiver operating characteristic curve of 0.806. This non-invasive gene expression profile of SSL-RNAs may contribute to early PD diagnosis based on the neurodegeneration background.

Role of botulinum toxin A in improving facial erythema and skin quality

Botulinum toxin A (BTX-A) injections have become the most popular noninvasive cosmetic procedures performed worldwide. With growing interest, investigators continue to uncover an expanding array of aesthetic indications for BTX-A. Botulinum toxin A has been used off-label in the management of masseter hypertrophy for facial slimming, platysmal bands, nasal 'bunny' lines, perioral rhytides, gummy smile and scars, to name a few. Interestingly, the injection of multiple microdroplets of dilute BTX-A into the dermis, sometimes referred to as 'microbotox', has been investigated as a tool for facial rejuvenation. A handful of prospective studies and case series have demonstrated the benefit of BTX-A in the treatment of facial erythema and improving skin texture. The aim of this review is to summarize and appraise currently available data on the role of BTX-A in treating facial erythema and skin quality, with a special focus on potential pathophysiologic mechanisms.

Ferredoxin reductase regulates proliferation, differentiation, cell cycle and lipogenesis but not apoptosis in SZ95 sebocytes

Ferredoxin reductase (FDXR), a mitochondrial membrane-associated flavoprotein, is essential for electron transfer and modulates p53-dependent apoptosis in cancer cells.FDXR may be implicated in epidermal and sebocytic differentiation, but its explicit function in sebocytes remains to be elucidated. In the present study, immunohistochemistry revealed that FDXR expression was increased in sebaceous cells of acne lesions. FDXR, PPARγ, LXRα/β, SREBP1 and Sox9 expression was incremental during sebocyte differentiation. FDXR overexpression induced by Ad-GFP-FDXR infection enhanced differentiation, reactive oxygen species (ROS), lipogenesis and PPARγ expression, and consequnently inhibited proliferation in SZ95 sebocytes. Flow cytometry showed that FDXR overexpression induced significant blockade of G2/M phase but had no effect on sub-G1 (apoptotic) sebocytes. Insulin-like growth factor-1 (IGF-1)-induced FDXR and PPARγ expression and lipogenesis were abolished by pretreatment with PI3K inhibitor LY294002. These results suggest that FDXR overexpression might promote differentiation and lipogenesis via ROS production and suppress proliferation via G2/S blockade in SZ95 sebocytes. IGF-1 could facilitate differentiation and lipogenesis through PI3K/Akt/FDXR pathway. FDXR could serve as a potential marker of advanced sebaceous differentiation, and its overexpression may be involved in the development of acne lesions.

The effectiveness of botulinum toxin type A (BTX-A) in the treatment of facial skin oily seborrhea, enlarged pores, and symptom complex of post-acne

BACKGROUND

This study aimed to examine the effectiveness of botulinum toxin type A (BTX-A) in the treatment of acne.

METHODS

The study was conducted in 2018 on 12 patients, 10 females and two males, aged 35 years on average. The injections with BTX-A were given during 2 weeks into the face skin in a dosage of 0.125-0.250 units.

RESULTS

Skin moisture indexes increased during the therapy by 4% (P ≤ 0.05), and porosity decreased by 7% (P ≤ 0.01). Maximal changes were recorded for the sulci and pigmentation of the skin, namely, its values decreased by 10 and 9%, respectively (P ≤ 0.01). BTX-A is recommended for an application not only in plastic surgeries but also for local correction of acne on the patient's skin.

CONCLUSION

A positive correlation was revealed between the duration of treatment and reduction of skin oiliness (0.87), pigmentation (0.78), skin sulci (0.84), and skin porosity (0.88), and negative correlation was established with increased skin moisture (-0.64). The obtained dependencies apply for the therapy period of up to 2 weeks. Pharmacological properties of BTX-A allow recommending it as a drug used in post-acne therapy.

Therapeutic Use of Botulinum Neurotoxins in Dermatology: Systematic Review

Botulinum toxin is a superfamily of neurotoxins produced by the bacterium Clostridium Botulinum with well-established efficacy and safety profile in focal idiopathic hyperhidrosis. Recently, botulinum toxins have also been used in many other skin diseases, in off label regimen. The objective of this manuscript is to review and analyze the main therapeutic applications of botulinum toxins in skin diseases. A systematic review of the published data was conducted, following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Botulinum toxins present several label and off-label indications of interest for dermatologists. The best-reported evidence concerns focal idiopathic hyperhidrosis, Raynaud phenomenon, suppurative hidradenitis, Hailey–Hailey disease, epidermolysis bullosa simplex Weber–Cockayne type, Darier’s disease, pachyonychia congenita, aquagenic keratoderma, alopecia, psoriasis, notalgia paresthetica, facial erythema and flushing, and oily skin. Further clinical trials are still needed to better understand the real efficacy and safety of these applications and to standardize injection and doses protocols for off label applications.

A Randomized, Double-Blinded Study Evaluating the Safety and Efficacy of AbobotulinumtoxinA Injections for Oily Skin of the Forehead: A Dose-Response Analysis

BACKGROUND

AbobotulinumtoxinA has been investigated for applications beyond facial rhytides, including the treatment of oily skin.

OBJECTIVE

The authors sought to investigate the optimal number of units and the duration of abobotulinumtoxinA for the treatment of oily skin.

MATERIALS AND METHODS

This randomized, double-blinded, placebo-controlled study included 50 male and female subjects that got either 0, 15, 30, or 45 units of abobotulinumtoxinA injected into their forehead. For the 6 months after treatment, subjects were evaluated for the effectiveness of the treatment in decreasing the oiliness of their skin and the duration of this effect.

RESULTS

Subjects in the treatment groups that received either 30 or 45 units of neurotoxin experienced a significant reduction in oily skin. This effect was present for the 6-month duration of the study. No treatment-related adverse events were reported during this study, and both subjects and investigators reported a high level of satisfaction with the treatment.

CONCLUSION

Thirty or 45 units of abobotulinumtoxinA are safe and effective doses in treating oily skin for improved cosmetic appearance.

The Efficacy and Safety of a Variable Square Pulse (VSP) Erbium:YAG Laser for Treatment of Enlarged Pores in Asians

BACKGROUND AND OBJECTIVES

Enlarged pores are one of the most common causes of skin surface irregularities. Existing studies supporting the benefit of lasers and energy-based devices (EBD) for this condition are limited, with a short duration of follow-up period. We aimed to evaluate the efficacy and adverse effects of Er:YAG laser for treatment of enlarged pores in dark-skinned patients.

STUDY DESIGN/MATERIALS AND METHODS

Nineteen subjects (aged 26-47 years) with skin phototypes III (21.1%) and IV (78.9%) and enlarged pores were treated with 4 monthly sessions of Erbium:YAG laser. Objective (ultraviolet light A video camera) and subjective (clinical evaluation by two blinded dermatologists) assessments were obtained at baseline, 1-month after each treatment and at 1, 3, and 6 months after the final treatment.

RESULTS

The weighted mean score of quartile grading scales showed significant improvement in pore size from baseline starting at 1-month after the third treatment and continued until 3 months after the fourth (final) treatment (P < 0.001). However, the improvement dropped significantly at 6 months after the final treatment. Objective measurements of the improvements in skin surface smoothness and wrinkles corresponded with the physician raters' clinical evaluation.

CONCLUSIONS

Erbium:YAG laser is a safe and effective treatment for enlarged pores in dark-skinned individuals. Maintenance treatments are recommended to achieve a longer-lasting outcome. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Effect of Genetic Polymorphisms of Human SLC22A3 in the 5'-flanking Region on OCT3 Expression and Sebum Levels in Human Skin

BACKGROUND

Human organic cation transporter 3 (OCT3,SLC22A3) mediates the uptake of many important endogenous substances and basic drugs, and has been identified as one of the transporters that are highly expressed in human skin. However, the mechanisms responsible for variability in mRNA expression, and the role of SLC22A3 in human skin is not clear.

OBJECTIVE

We examined the effects of the single nucleotide polymorphisms ofSLC22A3 on the variability in SLC22A3 expression and sebum levels in humans.

METHODS

Immunostaining of OCT3 in human skin was performed. We analyzed the association of promoter variants with the SLC22A3 mRNA expression levels in human skins. Luciferase, knockdown, chromatin immunoprecipitation (ChIP), electrophoretic mobility shift assay were employed to investigate transcriptional regulation of SLC22A3 expression. Effects of the identified variant on sebum levels were evaluated in healthy volunteers.

RESULTS

Immunohistochemistry revealed marked expressions of OCT3 in the basal epidermis, sebaceous glands, hair follicles, and sweat glands of human skin. SLC22A3 mRNA levels were significantly lower in skin samples with homozygotes for -1603A/A than in those for -1603 G/G. The analysis of p53 binding to -1603 G > A in the promoter ofSLC22A3 suggested that -1603 G > A down-regulates SLC22A3 gene expression by decreased p53 binding in the vicinity of the -1603 site. In humans, squalene levels in samples from the back at the baseline were significantly lower in homozygotes for -1603A/A than in those for -1603 G/G.

CONCLUSION

These results suggest that the genetic variant contributes to the variability of expression and activities of OCT3 in human skin.

Targeting the α7 nicotinic acetylcholine receptor-A novel road towards the future treatment of skin diseases

Nicotinic acetylcholine receptors (nAChRs) are members of the superfamily of neurotransmitter-gated ion channels. The natural ligand for nAChRs is the endogenous neurotransmitter acetylcholine. Among the nAChRs is the α7nAChR. It is not only expressed by neural tissues but also in the skin. A number of different resident cutaneous cell types including epidermal keratinocytes, sebocytes and dermal fibroblasts express functional α7nAChR. Moreover, cells of the immune system such as lymphocytes, macrophages and monocytes, playing an important role in skin homeostasis, also express α7nAChR. Translational research focusing on the exploitation of the α7nAChR in dermatology has revealed that this neuroendocrine receptor could be promising target for the treatment of inflammatory skin diseases. For example, α7nAChR agonists can counteract transforming growth factor-β1-mediated responses in dermal fibroblasts, key effector cells in scleroderma. In accordance with this α7nAChR, agonists are effective in both inflammation and non-inflammation-driven models of experimentally induced skin fibrosis. Moreover, α7nAChR agonists can modulate expression of proinflammatory cytokines in epidermal keratinocytes that are crucially involved in the pathogenesis of psoriasis and other inflammatory skin diseases. Finally, the capability of α7nAChR agonists to suppress ultraviolet light A/B-induced responses, for example production of proinflammatory cytokines and oxidative stress, the latter crucially involved in dermal photoageing, points to a potential of such agents in the prevention of extrinsic skin ageing. Therefore, emphasis on translational research targeting the α7nAChR in skin may lead to the development of new treatment and prevention modalities against fibrosclerotic skin diseases, psoriasis vulgaris, atopic dermatitis, acne, photodermatoses and extrinsic skin ageing.

Neuroendocrinology and neurobiology of sebaceous glands

The nervous system communicates with peripheral tissues through nerve fibres and the systemic release of hypothalamic and pituitary neurohormones. Communication between the nervous system and the largest human organ, skin, has traditionally received little attention. In particular, the neuro-regulation of sebaceous glands (SGs), a major skin appendage, is rarely considered. Yet, it is clear that the SG is under stringent pituitary control, and forms a fascinating, clinically relevant peripheral target organ in which to study the neuroendocrine and neural regulation of epithelia. Sebum, the major secretory product of the SG, is composed of a complex mixture of lipids resulting from the holocrine secretion of specialised epithelial cells (sebocytes). It is indicative of a role of the neuroendocrine system in SG function that excess circulating levels of growth hormone, thyroxine or prolactin result in increased sebum production (seborrhoea). Conversely, growth hormone deficiency, hypothyroidism, and adrenal insufficiency result in reduced sebum production and dry skin. Furthermore, the androgen sensitivity of SGs appears to be under neuroendocrine control, as hypophysectomy (removal of the pituitary) renders SGs largely insensitive to stimulation by testosterone, which is crucial for maintaining SG homeostasis. However, several neurohormones, such as adrenocorticotropic hormone and α-melanocyte-stimulating hormone, can stimulate sebum production independently of either the testes or the adrenal glands, further underscoring the importance of neuroendocrine control in SG biology. Moreover, sebocytes synthesise several neurohormones and express their receptors, suggestive of the presence of neuro-autocrine mechanisms of sebocyte modulation. Aside from the neuroendocrine system, it is conceivable that secretion of neuropeptides and neurotransmitters from cutaneous nerve endings may also act on sebocytes or their progenitors, given that the skin is richly innervated. However, to date, the neural controls of SG development and function remain poorly investigated and incompletely understood. Botulinum toxin-mediated or facial paresis-associated reduction of human sebum secretion suggests that cutaneous nerve-derived substances modulate lipid and inflammatory cytokine synthesis by sebocytes, possibly implicating the nervous system in acne pathogenesis. Additionally, evidence suggests that cutaneous denervation in mice alters the expression of key regulators of SG homeostasis. In this review, we examine the current evidence regarding neuroendocrine and neurobiological regulation of human SG function in physiology and pathology. We further call attention to this line of research as an instructive model for probing and therapeutically manipulating the mechanistic links between the nervous system and mammalian skin.

The effect of botulinum toxin type A in different dilution on the contraction of fibroblast-In vitro study

BACKGROUND

Botulinum toxin type A (BoNT-A) may directly remodel dermal tissues or induce a loss of normal morphology and cytoplasmic retraction and spread. Intradermal injection was claimed to produce a dermo-lifting effect, including midface lifting by using low concentration with variable dilution.

OBJECTIVE

To understand how intradermal BoNT-A achieves tissue lifting, we examined different type of BoNT-A and their effects on dermal fibroblast contraction.

METHODS

Normal human dermal fibroblasts were treated with onabotulinumtoxin (ONA), abobotulinumtoxin (ABO), prabotulinumtoxinA (PRABO), incobotulinumtoxinA (INCO), and letibotulinumtoxin A (LETI) in dilutions used in real-world practice. Fifty fibroblasts per dilution were photographed and measured the length to demonstrate their contraction every 2 hours from baseline (0 hours) to 12 hours post-treatment.

RESULTS

ONA did not significantly decrease fibroblast lengths, at any timepoint or dilution. At 1:7 dilution ratios, ABO decreased fibroblast lengths after 2 hours and significantly after 10-12 hours. At 1:7, 1:8, 1:9, and 1:10 dilution, PRABO decreased length, and most rapidly at 1:7 and 1:8. At 1:6, 1:8, 1:9, and 1:10 dilution, INCO decreased lengths almost immediately. At 1:6 dilution, INCO decreased lengths almost immediately. At 1:7 dilution, INCO decreased lengths after 2-4 hours, while at 1:8, 1:9, and 1:10 dilution, INCO decreased lenghts nearly imediately. LETI decreased lengths at all dilutions except 1:9, with near-immediate effects at 1:6, 1:7, 1:8, and 1:10. At 1:4 dilution, LETI decreased lengths from 1 hour.

CONCLUSIONS

Different commercial preparations of BoNT-A toxins cause different fibroblast contractions in vitro. Product selection and dilution used may affect the clinical outcome of intradermal injection of BoNT-A for face lifting.

Alterations in IL-4, IL-10 and IFN-γ levels synergistically decrease lipid content and protein expression of FAS and mature SREBP-1 in human sebocytes

When anti-acne alternatives from dietary and plant sources are ingested, systemic alterations of interleukin (IL)-4, IL-10, IL-12 and interferon (IFN)-γ, individually or simultaneously, are induced at a 0.1-10.0-fold (×) range of normal physiological concentrations (1×). However, little is known about the effects of these cytokines on excess sebum, a pathophysiological factor of acne development. In this study, human sebocytes were treated with 0.1-10.0× of IL-4, IL-10, IL-12 and IFN-γ for 3 or 5 days to elucidate the effects on lipid content. Treatment with individual cytokines decreased the lipid content at specific concentrations rather than in a concentration-dependent manner. Specifically, 5.0× of IL-4, 5.0× of IFN-γ (5.0IFN), and 0.5×, 5.0× and 10.0× of IL-10 for 3 days, and 0.5× of IL-4 (0.5IL4) for 5 days decreased lipid content to 87.6-93.0% of the control. Treatment with other concentrations of IL-4, IL-10 and IFN-γ, and 0.1-10.0× of IL-12 did not alter lipid content. Combined treatment with 0.5IL4, 5.0IFN and 0.5× of IL-10 for 3 or 5 days decreased the lipid content more than each individual treatment. However, this effect was more evident after 3 days, in parallel with decreased levels of triglycerides, cholesterol esters and free fatty acids, the major lipid compositions of sebocytes, and decreased protein expression of fatty acid synthase (FAS) and mature sterol response element-binding protein-1 (SREBP-1), the lipogenesis-related factors, without altered cell proliferation. We demonstrated that suppressed IL-4 and IL-10 with enhanced IFN-γ synergistically decreased lipid content and protein expression of FAS and mature SREBP-1 in human sebocytes.

Efficacy and possible mechanisms of botulinum toxin treatment of oily skin

BACKGROUND

Oily skin is one of the most common dermatological complaints. Oily skin may be accompanied by enlarged pores, acne, and seborrheic dermatitis. Moreover, oily skin has negative effects on self-perception. Most therapeutic approaches used to treat oily skin have had varying degrees of efficacy and include topical treatments, such as photodynamic therapy and lasers. However, certain of these therapies for oily skin may lead to severe side effects. With the expanding use and high safety profile of botulinum toxin type A (BoNT-A), its use in the treatment of oily skin has caused significant concerns; moreover, relevant reports have gradually accumulated to address the efficacy of BoNT-A and explore its mechanisms of action.

AIMS

The objective of this article was to review the efficacy and possible treatment mechanisms of BoNT-A on oily skin.

METHODS

A retrospective review of the published data was conducted.

RESULTS

Most studies have suggested that the intradermal injection of BoNT-A decreased sebum production and pore size. Furthermore, this treatment attained high patient satisfaction without significant side effects. BoNT-A effectively decreased sebum production and excretion, which was in keeping with previous studies, possibly via its blockade of cholinergic signaling and its neuromodulatory effects.

CONCLUSIONS

Intradermal BoNT-A injection may represent a promising new treatment for oily skin and other relevant dermatological problems, such as enlarged pores, acne, and seborrheic dermatitis. Further study is still needed to determine the specific mechanisms of BoNT-A and the optimal injection techniques and doses for oily skin and other relevant cosmetic concerns.

Emerging Therapies for Acne Vulgaris

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

Differentiation Model Establishment and Differentiation-Related Protein Screening in Primary Cultured Human Sebocytes

Sebocyte differentiation is a continuous process, but its potential molecular mechanism remains unclear. We aimed to establish a novel sebocyte differentiation model using human primary sebocytes and to identify the expression profiles of differentiation-associated proteins. Primary human sebocytes were cultured on Sebomed medium supplemented with 2% serum for 7 days. Flow cytometry showed that S phase cells were decreased time-dependently, while G1 and subG1 (apoptosis) phase cells increased under serum starvation. Transmission electron microscopy and Oil Red O staining revealed a gradual increase of intracellular lipid accumulation. Expression of proliferation marker was diminished, while expression of differentiation, apoptosis, and lipogenic markers elevated gradually during 7-day culture. iTRAQ analysis identified 3582 expressed proteins in this differentiation model. Compared with day 0, number of differentially expressed proteins was 132, 54, 321, and 96 at days 1, 3, 5, and 7, respectively. Two overexpressed proteins (S100 calcium binding protein P and ferredoxin reductase) and 2 downexpressed proteins (adenosine deaminase and keratin 10) were further confirmed by Western blot and immunohistochemistry.

The non-neuronal and nonmuscular effects of botulinum toxin: an opportunity for a deadly molecule to treat disease in the skin and beyond

There is growing evidence that botulinum neurotoxins (BoNTs) exhibit biological effects on various human cell types with a host of associated clinical implications. This review aims to provide an update on the non-neuronal and nonmuscular effects of botulinum toxin. We critically analysed recent reports on the structure and function of cellular signalling systems subserving biological effects of BoNTs. The BoNT receptors and intracellular targets are not unique for neurotransmission. They have been found in both neuronal and non-neuronal cells, but there are differences in how BoNT binds to, and acts on, neuronal vs. non-neuronal cells. The non-neuronal cells that express one or more BoNT/A-binding proteins, and/or cleavage target synaptosomal-associated protein 25, include: epidermal keratinocytes; mesenchymal stem cells from subcutaneous adipose; nasal mucosal cells; urothelial cells; intestinal, prostate and alveolar epithelial cells; breast cell lines; neutrophils; and macrophages. Serotype BoNT/A can also elicit specific biological effects in dermal fibroblasts, sebocytes and vascular endothelial cells. Nontraditional applications of BoNT have been reported for the treatment of the following dermatological conditions: hyperhidrosis, Hailey-Hailey disease, Darier disease, inversed psoriasis, aquagenic palmoplantar keratoderma, pachyonychia congenita, multiple eccrine hydrocystomas, eccrine angiomatous hamartoma, eccrine sweat gland naevi, congenital eccrine naevus, Raynaud phenomenon and cutaneous leiomyomas. Experimental studies have demonstrated the ability of BoNT/A to protect skin flaps, facilitate wound healing, decrease thickness of hypertrophic scars, produce an anti-ageing effect, improve a mouse model of psoriasiform dermatitis, and have also revealed extracutaneous effects of BoNT arising from its anti-inflammatory and anticancer properties. BoNTs have a much wider range of applications than originally understood, and the individual cellular responses to the cholinergic impacts of BoNTs could provide fertile ground for future studies.

Mode of action characterization for adverse effect of propranolol in Daphnia magna based on behavior and physiology monitoring and metabolite profiling

Studies are underway to gather information about the mode of action (MOA) of emerging pollutants that could guide practical environmental decision making. Previously, we showed that propranolol, an active pharmaceutical ingredient, had adverse effects on Daphnia magna that were similar to its pharmaceutical action. In order to characterize the mode of action of propranolol in D. magna, which is suspected to be organ-specific pharmaceutical action or baseline toxicity, we performed time-series monitoring of behavior along with heart rate measurements and nuclear magnetic resonance (NMR) based metabolite profiling. Principle component analysis (PCA) and hierarchical clustering were used to categorize the mode of action of propranolol among 5 chemicals with different modes of action. The findings showed that the mode of action of propranolol in D. magna is organ-specific and vastly different from those of narcotics, even though metabolite regulation is similar between narcotic and non-narcotic candidates. The method applied in this study seems applicable to rapid characterization of the MOA of other cardiovascular pharmaceutical ingredients.

Botulinum Toxin in the Field of Dermatology: Novel Indications

Since its approval by the US Food and Drug Administration in 2002 for glabellar wrinkles, botulinum toxin (BTX) has been widely used to correct facial wrinkles. As a result, many consider BTX synonymous with cosmetic dermatology. Recent studies indicate that BTX elicits biological effects on various skin cell types via the modulation of neurotransmitter release, and it seems that BTX has a wider zone of dermatologic influence than originally understood. Clinicians and researchers are now beginning to explore the potential of BTX beyond the amelioration of facial lines and encouraging results are seen with BTX in a variety of skin conditions. In this paper, we review novel dermatological indications of BTX which includes (but not limited to) scar prevention, facial flushing, post-herpetic neuralgia and itch. These areas show great promise, but there is definite need for larger, double-blinded, randomized control trials against established treatments before BTX becomes a clinical reality.

Preventive, Cumulative Effects of Botulinum Toxin Type A in Facial Aesthetics

BACKGROUND

Botulinum toxin Type A (BoNTA) is the gold standard for the treatment of dynamic rhytides in the face. Recently, clinical observation suggests that individuals who receive regular injections of BoNTA experience ongoing wrinkle reduction and improvements in overall skin quality not observed in those treated sporadically.

OBJECTIVE

To review scientific evidence of qualitative changes in the skin and the possibility of indirect or direct effects on fibroblasts affecting fibroblast activity, including collagen production, after repeated treatment with BoNTA.

MATERIALS AND METHODS

We examined the literature for supporting evidence of the effect of repeated treatment cycles on wrinkle reduction and skin quality; histological changes in collagen structure; alterations in biomechanical features of the skin; and potential fibroblastic response.

RESULTS

Apparent cumulative improvement on wrinkle reduction and additional skin quality attributes with regular BoNTA treatments suggests an ongoing process of dermal repair. Clinical observation suggests that BoNTA injections stimulate collagen production and lead to a reorganization of the collagen network within the extracellular matrix, which in turn may produce improvements in features associated with more youthful skin. Moreover, evidence suggests that BoNTA may have a direct or indirect effect on fibroblast activity.

CONCLUSION

Clinical observation of progressive wrinkle reduction and qualitative improvements in a number of skin attributes that accumulate with more frequent injections of BoNTA suggest an ongoing process of repair leading to prolonged and cumulative effects.

New Uses of AbobotulinumtoxinA in Aesthetics

BotulinumtoxinA (BoNT-A) is now widely established for the main approved indication of reducing glabellar lines, and is also widely used off-label to improve the appearance of wrinkles and lines in other parts of the face. The number of aesthetic procedures continues to increase as the patient population becomes more diverse, in particular with increasing numbers of people of color and men. Further developments in treatment may continue to expand the audience for BoNT-A by making procedures more comfortable and by delivering a more natural, less static appearance. These may be achieved through use of combinations of BoNT-A with other aesthetic procedures, tailoring the dose of toxin to the patient's muscle mass or by using novel injection and application techniques. Beyond amelioration of facial lines, encouraging results have been seen with the use of BoNT-A to improve the appearance of hypertrophic and keloid scars and even to prevent them. Studies have been conducted with scars in various parts of the body and further research is ongoing. Dermatological and other medical uses for BoNT-A are also active areas of research. Injections of BoNT-A have been shown to reduce signs and symptoms of acne, rosacea, and psoriasis, to reduce neuromuscular pain, and to bring about significant improvements in a number of rare diseases that are caused or exacerbated by hyperhidrosis. This paper reviews these new uses for BoNT-A, looking at the rationale for their use and discussing the results of published case studies and clinical trials. These areas have shown great promise to date, but more and larger clinical studies will be required before these treatments become a clinical reality. To this end details are also provided of clinical trials currently listed in the main clinical trials database to highlight research areas of particular interest.

Hyaluronic Acid Decreases Lipid Synthesis in Sebaceous Glands

Hyaluronic acid (HA) is the major glycosaminoglycan in the extracellular matrix and has been implicated in several functions in skin cells. However, evidence is lacking regarding the HA signaling in sebaceous glands, and its potential role needs to be clarified. We investigated the role of HA in lipid production in sebaceous glands in an experimental study of human sebocytes followed by a clinical study. We first examined the effects of HA on sebaceous glands in hamsters and intradermal injection of HA into hamster auricles decreased both the size of sebaceous glands and the level of lipid production. We demonstrated that human skin sebaceous glands in vivo and sebocytes in vitro express CD44 (HA binding receptor) and that HA downregulates lipid synthesis in a dose-dependent manner. To evaluate the clinical relevance of HA in human skin, 20 oily participants were included in a double-blind, placebo-controlled, split-face study, and the HA-treated side showed a significant decrease in sebum production. The results of this study indicate that HA plays a functional role in human sebaceous gland biology and HA signaling is an effective candidate in the management of disorders in which sebum production is increased.

Adiponectin Signaling Regulates Lipid Production in Human Sebocytes

Adiponectin plays important roles in metabolic function, inflammation and multiple biological activities in various tissues. However, evidence for adiponectin signaling in sebaceous glands is lacking, and its role remains to be clarified. This study investigated the role of adiponectin in lipid production in sebaceous glands in an experimental study of human sebocytes. We demonstrated that human sebaceous glands in vivo and sebocytes in vitro express adiponectin receptor and that adiponectin increased cell proliferation. Moreover, based on a lipogenesis study using Oil Red O, Nile red staining and thin layer chromatography, adiponectin strongly upregulated lipid production in sebocytes. In three-dimensional culture of sebocytes, lipid synthesis was markedly enhanced in sebocytes treated with adiponectin. This study suggested that adiponectin plays a significant role in human sebaceous gland biology. Adiponectin signaling is a promising target in the clinical management of barrier disorders in which sebum production is decreased, such as in atopic dermatitis and aged skin.