SciCombinator

Discover the most talked about and latest scientific content & concepts.

Journal: International journal of cosmetic science

169

A novel treatment serum formulated to target multiple pathways in the anti-ageing cascade was tested both in vitro and in clinical settings. In vitro testing was performed to assess the ability to stimulate key proteins and genes fundamental to the anti-ageing cascade. The antioxidant potential of the formulation was studied in a UV-irradiation clinical study. A 12-week, open-label, single-centre study was conducted to determine whether this uniquely formulated topical treatment serum could improve visible signs of facial photodamage. Clinical evaluations showed statistically significant reductions in fine wrinkles and coarse wrinkles and improvements in skin texture, tone and radiance starting at week 4 with continued improvements at weeks 8 and 12. Subject self-assessments confirmed that the beneficial effects of the treatment serum were readily observed by the users. The treatment serum was well tolerated with no treatment-related adverse events reported during the 12-week study. Use of this novel treatment serum produced significant improvements in the visible signs of facial photodamage.

Concepts: Better, Clinical trial, Improve, Statistical significance, Effectiveness, Clinical research, In vitro, Adverse event

31

Globally, billions of individuals wash their hair in water, which acts as an exogenous metal source. Many studies which measure the metal levels found on human hair specifically aim to remove exogenous materials prior to analysis. While this is needed when using hair analysis to probe the impact of the local environment on endogenous metal levels, it’s not relevant for understanding exactly what is on hair as a result of contact with its daily environment. Understanding these levels are important, as the presence of redox active metals, such as copper and iron, can impact fibre health, either due to UV irradiation, or during the hair colouring process. A global hair sampling study of over 300 individuals from nine countries has been performed, and the combined endogenous and exogenous metals analysed. The levels measured vary widely, even within the narrow geography of each hair sampling location. The levels of calcium, magnesium, copper and iron were not correlated, and within each location there are expected to be individuals with high metal levels. Levels increased from hair root to tip for calcium, magnesium and copper, attributed to hair’s contact with the environment showing the impact of exogenous metals in the overall levels on hair. Levels of redox metals were comparable between individuals who coloured or did not colour their hair, although water hardness ions were statistically significantly higher for hair colouring individuals. Individuals who perceived their hair health as poor had higher metal levels on their hair. Controlling metals on hair, either by preventing their binding during environmental contact, or through controlling their ability to cause hair damage, should lead to improved consumer perceived hair health. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Concepts: Iron, Hydrogen, Calcium, Chemical element, Aluminium, Metal, Electrolysis, Smelting

30

Mascara is a mild irritant that causes a range of medical problems. Animal models to predict ocular irritation have, however, been questioned at a number of levels, and there is a continued need to develop in vitro testing methods. We assess changes in an easily quantifiable attribute, ciliated protozoan growth rate, as a sensitive, sub-lethal measure. We provide evidence that two easily cultured protozoa (Paramecium caudatum, Blepharisma japonicum) should be considered as models to assess ocular irritancy (and possibly cosmetics in general) and establish the groundwork for such studies to be applied at a more commercial level. We do this by developing a bioassay for mascara toxicity and indicate the low-cost (after equipment is purchase, on the order of $100s) and the ease of performing such tests (able to be conducted by undergraduate students), as a consideration for their future commercial application. Specifically, we test six, randomly chosen, commercial mascara products against a control (as treatments) and reveal through ANOVA (n = 6, α=0.05) significant differences in the specific growth rate to treatments (for both protozoa): we first examined dose-dependence of responses, revealing that there was a need to conduct preliminary work to determine appropriate levels for sub-lethal responses. We then show that some products resulted in mortality at high concentrations, others decreased growth rate by >50% (compared to the control), while others had no significant effect, compared to the control. Now that we have provided a novel, quick, and inexpensive means to assess mascara, the next step is to validate these ciliate-bioassays by comparison with animal testing and epidemiological studies, which is beyond the scope of this fundamental “proof-of-concept” study. This article is protected by copyright. All rights reserved.

Concepts: Epidemiology, Measurement, In vitro, All rights reserved, Ciliate, Copyright, Paramecium caudatum, Ciliates

30

Few studies have tested the efficacy of commercially available cosmetic products for preventing striae gravidarum. Therefore, the objective of this study was to evaluate efficacy on prevention of striae gravidarum by using a specific anti-stretch mark cream containing hydroxyprolisilane-C, rosehip oil, Centella asiatica triterpenes and vitamin E. A randomized, double-blind, placebo-controlled trial was conducted between November 2009 and April 2011. Pregnant women were included and classified in treated group (emollient and moisturizer containing hydroxyprolisilane C, rosehip oil, Centella asiatica triterpenes and vitamin E) and control group (cream without the active ingredients). Overall incidence of stretch marks during pregnancy was 33.3% for the control group and 37.6% in the treated group (n.s.). Severity of previous stretch marks significantly increased in the control group during the study (17.8%, p = 0.001) but not in the treated group (6.3%, ns). In women who developed new stretch marks during the study, there was a significantly greater “difference in severity” (between baseline and maximum severity) in control group vs. treated group (0.47 [0.57] vs. 0.14 [0.60], p = 0.031). In women without previous striae, incidence of these marks was significantly lower for the treated group patients compared to control group (5.6% vs. 35%, p = 0.031, OR: 9.2 [95% CI: 1.0-83.3]). The use of the anti-stretch mark product is proved to be effective in reducing severity of the striae during pregnancy, prevents the appearance of new striae and halts progression of those already present. In women who had no striae at baseline, use of the anti-stretch mark cream was more effective than placebo in preventing new stretch marks. © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Concepts: Pregnancy, Randomized controlled trial, Obstetrics, Placebo, Stretch marks, Centella asiatica

28

An obvious sign of ageing is hair greying, or the loss of pigment production and deposition within the hair shafts. Numerous mechanisms, acting at different levels and follicular locations, contribute to hair greying, ranging from melanocyte stem cells defects to follicular melanocyte death. One key issue that is in common to these processes is oxidative damage. At the hair follicle stem cells niche, oxidative stress, accelerated by B-cell lymphoma 2 gene (BCL-2) depletion, leads to selective apoptosis and diminution of melanocyte stem cells, reducing the repopulation of newly formed anagen follicles. Melanotic bulbar melanocytes express high levels of BCL-2 to enable survival from melanogenesis- and ultraviolet A (UVA)-induced reactive oxygen species (ROS) attacks. With ageing, the bulbar melanocyte expression of anti-oxidant proteins such as BCL-2, and possibly TRP-2, is reduced, and the dedicated enzymatic anti-oxidant defence system throughout the follicle weakens, resulting in enhanced oxidative stress. A marked reduction in catalase expression and activity results in millimolar accumulation of hydrogen peroxide, contributing to bulbar melanocyte malfunction and death. Interestingly, amelanotic melanocytes at the outer root sheath (ORS) are somewhat less affected by these processes and survive for longer time even within the white, ageing hair follicles. Better understanding of the overtime susceptibility of melanocytes to oxidative stress at the different follicular locations might yield clues to possible therapies for the prevention and reversal of hair greying.

Concepts: Oxygen, Redox, Oxidative stress, Oxidative phosphorylation, Reactive oxygen species, Superoxide dismutase, Hydrogen peroxide, Melanin

28

A multicentred study derived from the COLIPA in vitro UVA method was performed to assess the influence of test conditions on UVA protection factor (UVAPF) values in terms of amplitude, reproducibility between laboratories and correlation with in vivo UVA results. Eight products with a range of in vivo UVAPF from three to 29 were used. Two different types of plates, namely high-roughness (5 μm) and low-roughness (2 μm) plates, were used with a different application rate for each (1.3 mg cm(-2) and 0.75 mg cm(-2) respectively). The UVR dose applied to both plate types followed the same principle as the original test (1.2 J. cm(-2)  × UVAPF0). Strong, significant correlations between in vitro and in vivo UVAPF values were observed for both plate types (Pearson correlation > 0.9, P ≤ 0.01). The correlation and slope obtained with the low-roughness plates confirmed the previous results obtained by COLIPA. Across all laboratories, higher UVAPF values were obtained on the high-roughness plates (P < 0.01). Reproducibility of UVAPF values between laboratories was comparable between the two plate roughness values (low roughness, COV = 8%; high roughness, COV = 12%). Considering the in vitro/in vivo comparisons, a regression slope of 0.83 was observed for the low-roughness plates, in comparison with a value of 1.05 for the high-roughness plates. The accuracy of the method was improved, therefore, with the use of the high-roughness plates. With a constraint to recommend the use of only one plate type in the COLIPA UVA in vitro Test, the high-roughness plate was selected on an on-going basis to limit variability of results and to provide better accuracy with in vivo data.

Concepts: Scientific method, In vivo, Psychometrics, Calculus, In vitro, Correlation and dependence, Pearson product-moment correlation coefficient

28

This article is an introduction and general discussion regarding the use of Fisher-Tropsch wax in petroleum jelly applications. Traditionally, petroleum jelly is prepared from a blend of microwax, paraffin wax and mineral oil that are all derived from crude oil. Sasol Wax has successfully prepared a petroleum jelly based on predominantly to fully synthetic Fisher-Tropsch wax. Sasol Wax was awarded a patent P53898ZP00-29 November 11 for a predominantly to fully synthetic petroleum jelly based on Fisher-Tropsch wax blends. The benefits of Fisher-Tropsch wax discussed in this article include the absence of aromatic compounds and polycyclic aromatic compounds in Fisher-Tropsch wax as well as the sustainable production that is possible with Fisher-Tropsch wax, as opposed to paraffin wax that may be affected by the closure of group I Base Oil plants. This article will be the first in a series of articles from the same authors, and follow-up articles will include solid-state nuclear magnetic resonance and crystallization studies to determine the influence of predominantly synthetic waxes on petroleum jelly network structures compared with more traditional mineral oil-derived petroleum jellies, final product performance and stability of synthetic petroleum jelly used in, for example, personal care lotions or creams. The influence of oxygenated compounds and product safety and rheological properties (including primary skin feel upon application and secondary skin feel after application) of synthetic petroleum jellies compared with traditional mineral oil-derived petroleum jellies are discussed.

Concepts: Petroleum, Polycyclic aromatic hydrocarbon, Hydrocarbon, Paraffin, Wax, Alkane, Beeswax, Mineral oil

28

Dandruff is a common complaint and is suffered by as much as half of the population at some time post puberty. The condition is characterized by the presence of flakes on the scalp and in the hair, and is often accompanied by itch. The most common treatment for dandruff is the use of shampoo formulations that contain fungistatic agents such as zinc pyrithione (ZPT) and octopirox. Whilst most antidandruff shampoos are effective in resolving the symptoms of dandruff these shampoos can often result in hair condition that is less than acceptable to consumers which can lead to a tendency for them to revert to use of a non-antidandruff shampoo. This can result in a rapid return of dandruff symptoms. The aim of this investigation was to study the impact of using a combination of antidandruff actives and silicones on the resolution of dandruff and to deliver superior sensory properties to the hair. We have demonstrated that shampoo containing the dual active system of ZPT/Climbazole deposits both active agents onto a model skin surface (VitroSkin) and reduces Malassezia furfur regrowth in vitro. Clinical evaluation of the dual active shampoo demonstrated superior efficacy and retained superiority during a regression phase where all subjects reverted to using a non-antidandruff shampoo. We have also demonstrated that it is possible to deposit silicone materials from antidandruff shampoo uniformly over both virgin and damaged hair fibres that results in smoother hair fibres (as evidenced by reduced dry friction). This combination of antidandruff agents and conditioning silicones delivered from a shampoo provides subjects with superior antidandruff efficacy and desired end sensory benefits ensuring compliance and longer term dandruff removal.

Concepts: Hair care, Silicone, Ketoconazole, Malassezia, Hair conditioner, Shampoo, Dandruff, Zinc pyrithione

27

Malassezia species are frequently associated with dandruff and seborrhoeic dermatitis. The study was conducted to evaluate antifungal activities of the extracts obtained from the roots of Asparagus racemosus Willd against Malassezia furfur and M. globosa. A. racemosus roots were successively extracted with the series of solvents i.e. hexane, ethanol and water and also a saponin enriched fraction was prepared. The amounts of saponin (equivalent to shatavarin IV) in the extracts were determined by ELISA. The extracts were tested for antifungal activity by disc diffusion and broth microdilution methods. By disc diffusion, only the ethanolic and saponin enriched extracts demonstrated antifungal activity against M. furfur and M. globosa at the concentration of 1 mg/disc while the extracts with other solvents were ineffective. Multiple concentrations using the broth microdilution method against M. furfur and M. globosa yielded minimum inhibitory concentrations (MICs) of 25 mg mL(-1) for the ethanolic extract but much higher potency for the saponin enriched extract: MICs to 0.20 and 0.40 mg mL(-1) for M. furfur and M. globosa, respectively. These extracts showed no antagonist effect with the antifungal agents, ketoconazole and zinc pyrithione. Since A. racemosus is also anti-inflammatory agent, it has the potential use as an active ingredient in an anti-dandruff formulation. This article is protected by copyright. All rights reserved.

Concepts: Ethanol, Antifungal drug, Copyright, Ketoconazole, Malassezia, Seborrhoeic dermatitis, Dandruff, Zinc pyrithione

27

Skin compartments traditionally targeted by cosmetic actives - epidermis and dermis - are anchored and nourished by the underlying hypodermis, which therefore should be a key target for skin-rejuvenating formulations. However, given the difficulty to reach even the superficial layers of the skin, and to its “unglamorous” fatty composition, the regenerative potential of hypodermis remains largely untapped. Therefore, this study was to investigate the capacity of a cosmetic material to trigger a regenerative response in dermis and epidermis through a selective action on hypodermis. Furthermore, it aimed to establish the effect of such cosmetic material in transbuccal hypodermal delivery form, on the hypodermal precursor cells - the preadipocytes.

Concepts: Nutrition, Fat, Skin, Dermis, Epidermis, Subcutaneous tissue, Subcutis