Effects of atopic dermatitis on the morphology and water content of scalp hair

Role and Mechanisms of Phytochemicals in Hair Growth and Health

Hair health is associated with personal distress and psychological well-being. Even though hair loss (alopecia) does not affect humans' biological health, it affects an individual's social well-being. So, treatment for hair problems and improving hair health are obligatory. Several pharmacological and cosmeceutical treatment procedures are available to manage hair loss and promote growth. Several factors associated with hair health include genetics, disease or disorder, drugs, lifestyle, chemical exposure, and unhealthy habits such as smoking, diet, and stress. Synthetic and chemical formulations have side effects, so people are moving towards natural compounds-based remedies for their hair problems. The history of using phytochemicals for hair health has been documented anciently. However, scientific studies on hair loss have accelerated in recent decades. The current review summarizes the type of alopecia, the factor affecting hair health, alopecia treatments, phytochemicals' role in managing hair loss, and the mechanisms of hair growth-stimulating properties of phytochemicals. The literature survey suggested that phytochemicals are potent candidates for developing treatment procedures for different hair problems. Further detailed studies are needed to bring the scientific evidence to market.

Allergic Contact Dermatitis of the Scalp Associated With Scalp Applied Products: A Systematic Review of Topical Allergens

ABSTRACT

Hair products are commonly used to maintain hair health or cosmesis. Products applied to the scalp and hair contain multiple active and inactive ingredients that can potentially cause irritant and/or allergic contact dermatitis. The objectives of this study were to identify and to discuss the most common allergens in scalp and hair applied products causing scalp allergic contact dermatitis (ACD). A PubMed search identified 99 studies, with 3185 patients and 31 categories of scalp products. Hair products reportedly associated with scalp ACD were hair dyes (41%), shampoos (28%), and conditioners (22%). The most commonly reported patch test-positive allergens were p-phenylenediamine (23%), nickel (15%), fragrance mix (13%), balsam of Peru (10%), cocamidopropyl betaine/3-dimethylaminopropylamine (7%), and methylchloroisothiazolinone/methylisothiazolinone (6%). Common symptoms and signs include eczematous lesions, pruritus, and a burning sensation. Medical practitioners should be aware of causative agents to provide appropriate patient education, counseling, and/or treatment.

Role of Scalp Health in Achieving Optimal Hair Growth and Retention

We have conducted a thorough review of the literature to assess the evidence for supporting a cause-and-effect linkage between scalp condition and resultant hair condition. Over 20 epidemiological studies have been published covering a wide range of abnormal scalp conditions in which consequent impacts to the hair have been documented. A treatment study was conducted to demonstrate not only that impaired scalp condition led to impaired hair quality but that the impacts to hair are reversible upon normalization of the scalp condition. A proposed explanation involves the impact of scalp oxidative stress, which is part of the etiology of these scalp conditions as well as normal aging, in interfering with the normal keratinization of the pre-emergent hair cuticle. This perturbed cuticle impedes normal fiber anchorage and emerges more brittle and fragile than normal cuticle leading to accelerated physical degradation, mirroring the effects of chronological aging of the hair fiber. The consequences of the rapid cuticle degradation result in hair that is more vulnerable to mechanical insults and compromised overall quality.

The antimicrobial protein S100A12 identified as a potential autoantigen in a subgroup of atopic dermatitis patients

Background

Atopic dermatitis (AD) is a complex heterogeneous chronic inflammatory skin disease. Specific IgE antibodies against autoantigens have been observed in a subgroup of AD patients, however, little is known about IgG-auto-reactivity in AD. To investigate the presence of autoreactive IgG antibodies, we performed autoantibody profiling of IgG in patients with AD of different severities and in healthy controls (HC).

Methods

First, we performed an untargeted screening in plasma samples from 40 severe AD (sAD) patients and 40 HC towards 1152 protein fragments on planar antigen microarrays. Next, based on the findings and addition of more fragments, a targeted antigen suspension bead array was designed to profile a cohort of 50 sAD patients, 123 patients with moderate AD (mAD), and 84 HC against 148 protein fragments representing 96 unique proteins.

Results

Forty-nine percent of the AD patients showed increased IgG-reactivity to any of the four antigens representing keratin associated protein 17-1 (KRTAP17-1), heat shock protein family A (Hsp70) member 4 (HSPA4), S100 calcium binding proteins A12 (S100A12), and Z (S100Z). The reactivity was more frequent in the sAD patients (66%) than in those with mAD (41%), whereas only present in 25% of the HC. IgG-reactivity to S100A12, a protein including an antimicrobial peptide, was only observed in AD patients (13/173).

Conclusions

Autoantibody profiling of IgG-reactivity using microarray technology revealed an autoantibody-based subgroup in patients with AD. The four identified autoantigens and especially S100A12 could, if characterized further, increase the understanding of different pathogenic mechanisms behind AD and thereby enable better treatment.

Electronic supplementary material

The online version of this article (10.1186/s13601-019-0240-4) contains supplementary material, which is available to authorized users.

Scalp Condition Impacts Hair Growth and Retention via Oxidative Stress

Conventionally, the medical focus has been either on hair loss or the condition of the scalp in terms of specific dermatological diseases. Indeed, the proximate structural arrangement of the scalp and hair leads to an interdependent relationship between the two. While protective benefits of the hair to the scalp are obvious, the role of the scalp as an incubatory environment for the preemergent hair fiber has largely been ignored. In fact, there is a wealth of observational data on specific dermatological conditions of the scalp providing evidence for the role of the scalp condition in supporting the production of healthy hair. Oxidative stress, the inability of the body to sufficiently counteract the sources of oxidation, is prevalent in many skin conditions, including normal skin aging. On the scalp, the hair appears to be impacted prior to emergence, and oxidative stress appears to play a role in premature hair loss. The scalp commensal organism, Malassezia, has been recognized to be a source of oxidative damage. Therefore, hair care products, specifically shampoos, with active Malassezia inhibitory agents, such as zinc pyrithione, tend to reduce premature hair loss, besides the known benefits in treating specific dermatologic scalp pathologies, and therefore should represent an integral part of every treatment regimen for hair loss, even in individuals not showing symptoms of scalp pathologies.

A Comment on the Science of Hair Aging

In contrast to the skin, aging of the hair has seemingly only recently found the attention of dermatological meetings, mainly promoted by the cosmetic industry for marketing purposes. In fact, basic scientists interested in the biology of hair growth and pigmentation have for some time already exposed the hair follicle as a highly accessible model with unique opportunities for the study of age-related effects. As a result, the science of hair aging focuses on two main streams of interest: the esthetic problem of aging hair and its management, in terms of age-related effects on hair color, quantity, and quality; and the biological problem of aging hair, in terms of microscopic, biochemical, and molecular changes underlying the aging process. Ultimately, the aim of hair anti-aging is to delay, lessen, or reverse the effects of aging on hair. According to the complex nature of the aging process, the treatment for lifetime scalp and hair health has to be holistic to include the multitude of contributing factors in a polyhedral and patient-specific manner. It comprises both medical treatments and hair cosmetics. Accordingly, the discovery of pharmacological targets and the development of safe and effective drugs for treatment of hair loss indicate strategies of the drug industry for maintenance of hair growth and quantity, while the hair care industry has become capable of delivering active compounds directed toward meeting the consumer demand for maintenance of hair cosmesis and quality. “Where there's life, there's hope” (Ecclesiastes 9:3-5).

Incubatory environment of the scalp impacts pre-emergent hair to affect post-emergent hair cuticle integrity

OBJECTIVES

To determine whether the oxidative stress transmitted to newly grown hair from an unhealthy scalp has physical consequences to the cuticular condition and function.

METHODS

A uniquely designed 24-week clinical study included 8 weeks of pretreatment with a cosmetic shampoo and 16 weeks of treatment with either a potentiated zinc pyrithione (ZPT) antidandruff shampoo or a placebo cosmetic shampoo. This clinical design allowed the growth and acquisition of hair samples under conditions of varying but known scalp health as a result of treating a dandruff/seborrheic dermatitis (D/SD) population. Two complementary methods were used to characterize the integrity of the cuticular surface. Hair surface hydrophobicity was assessed by quantifying water wetting force using a Wilhelmy balance method. Surface structure and porosity were assessed using dynamic vapor sorption (DVS) to gravimetrically quantify water sorption.

RESULTS

Chemical oxidative stress to pre-emergent hair has been shown to have negative consequences to hair surface structure. Compared to a placebo shampoo control, use of a potentiated ZPT shampoo improved scalp health and significantly improved the following attributes associated with healthy hair: hair surface hydrophobicity (surface energy) and cuticular moisture barrier effectiveness (dynamic vapor sorption).

CONCLUSIONS

Pre-emergent hair can be negatively impacted by the oxidative stress that occurs with an unhealthy scalp, possibly due to metabolic activity of resident microbes. Manifestations of the oxidative stress include altered cuticle surface properties that are responsible for its protective function; these effects are similar in type to those observed by bleaching post-emergent hair. These alterations have the potential to make the hair, once emerged from the scalp, more susceptible to the cumulative physical and chemical insults responsible for hair feel and look, fiber integrity, and overall retention.

The role of oxidative damage in poor scalp health: ramifications to causality and associated hair growth

The oxidative stress element of unhealthy scalp leads to compromised pre-emergent hair formation and poorly formed hair as it grows. Only cosmetic solutions can minimize the impact of unhealthy hair and to achieve healthy looking and feeling hair, the scalp health must be normalized first. The objectives of this research were to both investigate whether oxidative stress was a relevant aetiological element in scalp dandruff and seborrhoeic dermatitis and whether scalp condition affects the quality of hair that grows from it. Further, this research was designed to determine whether an effective anti-dandruff shampoo would repair and protect the scalp and pre-emergent hair from oxidative stress. This study demonstrated that oxidative stress is an aetiological element relevant to the dandruff condition and that a potentiated ZPT shampoo effectively improves scalp condition, including a reduction in oxidative stress. The compromised hair condition associated with dandruff is concomitantly improved when the scalp condition is improved. It appears that there is a direct link between hair quality and scalp health.

Effects of scalp dermatitis on chemical property of hair keratin

The effects of scalp dermatitis (seborrheic dermatitis (SD), psoriasis, and atopic dermatitis (AD)) on chemical properties of hair keratin were investigated by Fourier transform infrared (FT-IR) spectroscopy. Hairs were collected from lesional regions affected by SD, psoriasis, and AD and non-lesional regions separately. The hairs with SD were taken from patients with ages of 16-80 years. The ages of patients with psoriasis ranged from 8 to 67 years, and all patients exhibited moderate disease. Hairs with AD were taken from the patients with ages of 24-45 years and the average SCORing atopic dermatitis (SCORAD) was 48.75. Hairs from 20 normal adults were collected as a control. The FT-IR absorbance bands were analyzed by the Gaussian model to obtain the center frequency, half width, height, and area of each band. The height and area of all bands in the spectra were normalized to the amide I centered at 1652 cm(-1) to quantitatively analyze the chemical composition of keratin. The spectra of hair with scalp dermatitis were different with that of control, the amide A components centered at 3278 cm(-1) were smaller than those of the control. The psoriasis hair showed a large difference in the IR absorbance band between lesional and non-lesional hairs indicating good agreement with the morphological changes. The hairs with diseases did not show differences in the content of cystine, which was centered at 1054 cm(-1), from the control. The chemical properties of keratin were not significantly different between the hairs affected by SD, psoriasis, and AD. However, the changes induced by scalp dermatitis were different with weathering. Therefore, FT-IR analysis could be used to screen differences between the physiological and pathological conditions of scalp hair.

A honey trap for the treatment of acne: manipulating the follicular microenvironment to control Propionibacterium acnes

Today, as 40 years ago, we still rely on a limited number of antibiotics and benzoyl peroxide to treat inflammatory acne. An alternative way of suppressing the growth of Propionibacterium acnes is to target the environment in which it thrives. We conjecture that P. acnes colonises a relatively “extreme” habitat especially in relation to the availability of water and possibly related factors such as ionic strength and osmolarity. We hypothesise that the limiting “nutrient” within pilosebaceous follicles is water since native sebum as secreted by the sebaceous gland contains none. An aqueous component must be available within colonised follicles, and water may be a major factor determining which follicles can sustain microbial populations. One way of preventing microbial growth is to reduce the water activity (a_w) of this component with a biocompatible solute of very high water solubility. For the method to work effectively, the solute must be small, easily diffusible, and minimally soluble in sebaceous lipids. Xylose and sucrose, which fulfil these criteria, are nonfermentable by P. acnes and have been used to reduce water activity and hence bacterial colonisation of wounds. A new follicularly targeted topical treatment for acne based on this approach should be well tolerated and highly effective.

Efficacy of a new tonic containing urea, lactate, polidocanol, and glycyrrhiza inflata root extract in the treatment of a dry, itchy, and subclinically inflamed scalp

BACKGROUND/AIMS

Dry, itchy and inflamed scalp conditions are common and often associated with diseases such as atopic dermatitis or psoriasis. To improve these symptoms, we investigated the efficacy of a new tonic containing the active ingredients urea, lactate, polidocanol, and Glycyrrhiza inflata root extract, containing licochalcone A.

STUDY DESIGN/METHODS

30 subjects with dry and itchy scalp conditions underwent a randomized half-head study for 4 weeks, applying the leave-on tonic three times a week on one side of the scalp. Tonic effects on skin hydration, itching, lipids, microinflammation, and substantivity of tonic compounds were determined using corneometry, middle-infrared spectroscopy, direct analysis in real-time mass spectrometry, and enzyme-linked immunosorbent assay. Volunteers performed a self-assessment; changes in scalp condition were documented by in vivo microscopy.

RESULTS

After tonic treatment, scalp moisture was significantly increased, whereas scalp itching and tautness were significantly reduced. Results also demonstrated a high substantivity of urea and lactate on the scalp, an increase in triglyceride, and a decrease in free fatty acid levels. The amount of total lipids was unchanged. Analyses of scalp wash-ups verified a significant reduction in important pro-inflammatory markers.

CONCLUSION

Due to the actives urea, lactate, polidocanol, and the anti-inflammatory licochalcone A, the new scalp tonic exhibited excellent performance in alleviating scalp dryness, itching, microinflammation, and in normalizing disturbances of scalp lipids.