Post-Inflammatory Hyperpigmentation (PIH) is a common pigmentary disorder in patients with pigmented skin. Histological and clinical exams have been used for the diagnosis of PIH and to determine the correct treatment. However, Reflectance Confocal Microscopy (RCM) has the potential to replace these methods since it is a noninvasive advanced technique and has a higher diagnostic accuracy than dermatoscopy. The aim of this study was to characterize PIH and correlate the main aspects observed by RCM with the macroscopic characteristics of acne-related PIH. Thus, 12 subjects with previously diagnosed acne and PIH were selected for the study. PIH was evaluated by RCM. The brightness of the basal cell layer, the dermal-epidermal junction (DEJ) thickness, and the depth of dermal papillae were quantified and the morphological and structural features of the DEJ were analyzed. The results showed an increase of epidermal pigmentation, a reduction of DEJ thickness, and no change in epidermal thickness. Melanophages were observed in the papillary dermis, as well as changes in the size and shape of dermal papillae. Finally, the study describes the characteristics of PIH and can help dermatologists to diagnose PIH with an innovative method that reduces the stress associated with a histological biopsy.

Vitamin D supplementation is important to prevent and treat hypovitaminosis that is a worldwide public health issue. Most types of supplementation are by oral route or fortification foods. The alternative route must be investigated, as transdermal route, for people with fat malabsorption or other diseases that impair the absorption of vitamin D. This study focused on verifying the feasibleness of vitamin D skin retention and permeation with the presence of chemical penetration enhancers (soybean lecithin, isopropyl palmitate, propylene glycol, ethoxydiglycol, and cereal alcohol) at different pharmaceutical forms (gel and cream) through a human skin. The integrity of skin was evaluated by transepidermal water loss (TEWL) during the skin retention and permeation test. The combination of chemical penetration enhancers presented in cream did not compromise the skin, different from the gel that association of cereal alcohol and propylene glycol compromised the skin in 24 h. Gel formulation showed vitamin D detection at stratum corneum in 4 h and at epidermis and dermis in 24 h. Vitamin D demonstrated an affinity with the vehicle in the cream formulation and was detected at the skin surface. No active was found at receptor fluid for both formulations. In conclusion, the vitamin D did not indicate feasibleness for transdermal use probably due to its physical-chemical characteristics such as high lipophilicity since it was not permeated through a human skin. Nevertheless, the transdermal route should be continuously investigated with less lipophilic derivates of vitamin D and with different combination of penetration enhancers.

Development of cosmetic formulations based on natural ingredients presents a challenge in order to instability and sensory limitations of raw ingredients. Organogel which is a cold emulsifier and offers refined sensory properties, physical-chemical characteristics and stability could be solved this limitation. The aim of this study is to develop cosmetic formulations by cold process containing natural ingredients and assess through design of experiment (DOE) the influencing factors on the physical-mechanical and sensory properties of these formulations. Physico-mechanical and sensory properties of cosmetic formulations containing natural ingredients obtained by cold process were evaluated. The DOE was performed for the texture analyses. In addition, the influence of natural actives substances in the developed formulations was assessed. The different concentrations of polymers, organogel and active substances influenced the texture profile of the formulations, being the concentration of organogel the most influential factor. The formulation containing sunflower oil, a polymer from a natural source and the highest concentration of organogel influenced the firmness, consistency, cohesiveness and viscosity. The work of shear decreased in the formulation added of the polymer and increased when the formulation was supplemented with active substances. The sensory analysis showed that the formulation based on 5% of organogel, sunflower oil and polymer it was preference for the selected formulation. In conclusion, the application of DOE for the rational development of cosmetic formulations based on natural ingredients led to formulations with physico-mechanical and sensory properties suitable for the application on the skin.

Collagen and its peptides are natural ingredients used in food supplements and nutricosmetics with the claim of providing benefits for skin health and beauty. In this context, the aim of the present study was to evaluate the clinical efficacy of oral supplementation with hydrolyzed fish cartilage for the improvement of chronological and photoaging-induced skin changes. A total of 46 healthy females aged 45 to 59 years were enrolled and divided into two groups: G1—placebo and G2—oral treatment with hydrolyzed fish cartilage. Measurements of skin wrinkles, dermis echogenicity and thickness, and morphological and structural characteristics of the skin were performed in the nasolabial region of the face before and after a 90-day period of treatment using high-resolution imaging, ultrasound, and reflectance confocal microscopy image analyses. A significant reduction in wrinkles and an increase of dermis echogenicity were observed after a 90-day period of treatment with hydrolyzed fish cartilage compared to the placebo and baseline values. In addition, reflectance confocal microscopy (RCM) image analysis showed improved collagen morphology and reduced elastosis after treatment with hydrolyzed fish cartilage. The present study showed the clinical benefits for the skin obtained with oral supplementation with a low dose of collagen peptides from hydrolyzed fish cartilage.

Significant advances have been achieved during the past decade concerning the metabolism of polyphenol compounds in vitro, but scarce data has been presented about what really happens in vivo. Many studies on polyphenols to date have focused on the bioactivity of one specific molecule in aglycone form, often at supraphysiological doses, whereas foods contain complex, often poorly characterized mixtures with multiple additive or interfering activities. Whereas most studies up to the middle-late 1990s measured total aglycones in plasma and urine, after chemical or enzymatic deconjugation, or both, several recent works now report the polyphenol conjugate composition of plasma, urine, feces and/or tissues, after the administration of pure polyphenols or polyphenol-rich matrices. HPLC methods with electrochemical, mass spectrometric and fluorescence detection have adequate sensitivity. LC/UV-Vis methods have also been widely reported, but they are much less sensitive. Compared with electro-chemical and fluorescence detection, MS can quantify analytes without chromatographic separation, which leads to high throughput, presenting itself as the best choice to date. Regarding the experimental model to monitor the bioavailability of phenolic compounds, most published studies are based on human and animal models, with the majority using rodents, primates and recently the nematode Caenorhabditis elegans. This review focuses on the fundamentals of pharmacokinetic methods from the last 15 years and how the results are evaluated and validated. The types of analytical methods, animal models and biological matrices were used to better elucidate pharmacokinetics of polyphenols.