Investigation on the Biological Safety and Activity of a Gluconolactone-Based Lotion for Dermocosmetic Application.

(1) Background: Cosmeceuticals are formulas enriched with active ingredients that exert efficacy on different skin molecular targets. (2) Methods: Cell viability and the absence of potential irritant risk were evaluated on keratinocytes (HaCaT), fibroblasts (NHDF), adipocytes (3T3-L1), sebocytes (PCi-SEB_CAU) and reconstructed human epidermis (RHE), respectively. Several treatments were performed to evaluate the ability of the lotion to stimulate the production of collagen and elastin, stimulate the differentiation of keratinocytes and reduce the number of senescent cells following UVB stimulation. In addition, the modulation of genes involved in the production, storage and accumulation of sebum were investigated. (3) Results: The results obtained demonstrated the biosafety of the formula in all cell lines tested. The 24-h treatment with non-cytotoxic concentrations determined an increase in the expression of the collagen (COL1A1), elastin (ELN) and involucrin (IVL) genes, while a reduction of peroxisome proliferator-activated receptor-gamma (PPARγ) gene expression and a reduction of SA-ßgal-positive cells were found. Moreover, the treatment did not interfere with normal steroid 5-alpha reductase (5RDA3) gene expression levels. (4) Conclusions: Data collected demonstrated the biosafety of the lotion, the non-comedogenic property and a multi targets anti-aging effect. In particular, data collected on the booster lotion make it a valid way to counteract the pore dilatation aging related.

Antimicrobial Efficacy Assessment and Rheological Investigation of Two Different Hand Sanitizers Compared with the Standard Reference WHO Formulation 1.

(1) Background: recently, the use of alcohol-based hand sanitizers (ABHSs) has become very frequent, and an evaluation of the stability and effectiveness of their formulations is a critical topic which should be carefully considered. (2) Methods: starting from the characterization of the hand sanitizers object of the study, our interest was focused on their rheological behavior in order to confirm their intrinsic features, but also the stability of each formulation in different conditions of shear and temperature; the second aspect concerns the antimicrobial assessment through a panel of in vitro and in vivo experimental trials. (3) Results: rheological investigation confirmed good stability for the two hand sanitizers in gel formula with respect to the reference in liquid formula; the antimicrobial activity evaluation showed good efficacy of each formulation both in vitro and in vivo. (4) Conclusions: altogether, our overview presents a valid quality control assessment to ensure the stability and efficacy of an alcohol-based hand sanitizer.

Crystal structure of the kringle domain of human receptor tyrosine kinase-like orphan receptor 1 (hROR1).

Receptor tyrosine kinase-like orphan receptors (RORs) are monotopic membrane proteins belonging to the receptor tyrosine kinase (RTK) family. RTKs play a role in the control of most basic cellular processes, including cell proliferation, differentiation, migration and metabolism. New emerging roles for RORs in cancer progression have recently been proposed: RORs have been shown to be overexpressed in various malignancies but not in normal tissues, and moreover an abnormal expression level of RORs on the cellular surface is correlated with high levels of cytotoxicity in primary cancer cells. Monoclonal antibodies against the extracellular part of RTKs might be of importance to prevent tumor cell growth: targeting extracellular kringle domain molecules induces the internalization of RORs and decreases cell toxicity. Here, the recombinant production and crystallization of the isolated KRD of ROR1 and its high-resolution X-ray crystal structure in a P3121 crystal form at 1.4 Šresolution are reported. The crystal structure is compared with previously solved three-dimensional structures of kringle domains of human ROR1 and ROR2, their complexes with antibody fragments and structures of other kringle domains from homologous proteins.

Rheological Investigation as Tool to Assess Physicochemical Stability of a Hyaluronic Acid Dermal Filler Cross-Linked with Polyethylene Glycol Diglycidyl Ether and Containing Calcium Hydroxyapatite, Glycine and L-Proline.

(1) Background: Dermal fillers are commonly used in aesthetic practice and their rheological characterization is of much interest today, as well as the stability study of the finished formula against external stimuli of a different nature (biological and physicochemical). Rheological tools have been exploited to characterize the physiochemical behaviour of a hyaluronic acid (HA) based dermal filler subjected to different thermal conditions over time. The collected results provide an index of its rheological stability. (2) Methods: After a preliminary Amplitude sweep test, the Frequency sweep test was performed in order to study the stability of a HA dermal filler cross-linked with Polyethylene Glycol Diglycidyl Ether (PEGDE) and containing Calcium Hydroxyapatite (CaHA), Glycine and L-Proline subjected to different conditions. Also, a shear rate ramp test was performed in order to investigate the filler's flow behavior. (3) Results and Conclusions: G' (elastic modulus), G'' (viscous modulus) and consequentially tan δ (tangent of the phase angle) show a similar trend at different thermal conditions, underlining that the product is not affected by the storage conditions. The viscosity of the dermal filler decreases with an increasing shear rate, so a non-Newtonian shear thinning pseudoplastic behavior was demonstrated in all tested conditions.

Biophysical and Biological Tools to Better Characterize the Stability, Safety and Efficacy of a Cosmeceutical for Acne-Prone Skin.

(1) Background: Acne is a widespread skin disease, especially among adolescents. Following the COVID-19 pandemic and the use of masks, the problem has been affecting a greater number of people, and the attention of the skin care beauty routine cosmetics has been focused on the "Maskne", caused by the sebum excretion rate (SER) that stimulates microbial proliferation. (2) Methods: the present study was focused on the rheological characterization and quality assurance of the preservative system of an anti-acne serum. The biological effectiveness (cytotoxicity-skin and eye irritation-antimicrobial, biofilm eradication and anti-inflammatory activity) was evaluated in a monolayer cell line of keratinocytes (HaCaT) and on 3D models (reconstructed human epidermis, RHE and human reconstructed corneal epithelium, HCE). The Cutibacterium acnes, as the most relevant acne-inducing bacterium, is chosen as a pro-inflammatory stimulus and to evaluate the antimicrobial activity of the serum. (3) Results and Conclusions: Rheology allows to simulate serum behavior at rest, extrusion and application, so the serum could be defined as having a solid-like behavior and being pseudoplastic. The preservative system is in compliance with the criteria of the reference standard. Biological effectiveness evaluation shows non-cytotoxic and irritant behavior with a good antimicrobial and anti-inflammatory activity of the formulation, supporting the effectiveness of the serum for acne-prone skin treatment.

A Practical Approach for the In Vitro Safety and Efficacy Assessment of an Anti-Ageing Cosmetic Cream Enriched with Functional Compounds.

(1) Background: Cosmeceuticals are topical products applied to human skin to prevent skin ageing and maintain a healthy skin appearance. Their effectiveness is closely linked to the compounds present in a final formulation. In this article, we propose a panel of in vitro tests to support the efficacy assessment of an anti-ageing cream enriched with functional compounds. (2) Methods: biocompatibility and the irritant effect were evaluated on reconstructed human epidermis (RHE) and corneal epithelium (HCE) 3D models. After a preliminary MTT assay, normal human dermal fibroblasts (NHDF) and keratinocytes (HaCaT) were used to evaluate the extracellular matrix (ECM) protein synthesis, and interleukin-6 (IL-6) and metalloproteinase-1 (MMP-1) production. (3) Results: data collected showed good biocompatibility and demonstrated the absence of the irritant effect in both 3D models. Therefore, we demonstrated a statistical increase in collagen and elastin productions in NHDF cells. In HaCaT cells, we highlighted an anti-inflammatory effect through a reduction in IL-6 levels in inflammatory stimulated conditions. Moreover, the reduction of MMP-1 production after UV-B radiation was demonstrated, showing significant photo-protection. (4) Conclusion: a multiple in vitro assays approach is proposed for the valid and practical assessment of the anti-ageing protection, anti-inflammatory and biocompatible claims that can be assigned to a cosmetic product containing functional compounds.

Comparative Physicochemical Analysis among 1,4-Butanediol Diglycidyl Ether Cross-Linked Hyaluronic Acid Dermal Fillers.

(1) Background: Injectable hyaluronic acid (HA) dermal fillers are used in several chirurgical practices and in aesthetic medicine. HA filler stability can be enhanced through different cross-linking technologies; one of the most frequently cross-linker used is 1,4-butanediol diglycidyl ether (BDDE), also present in the HA-BDDE dermal filler family of the company Matex Lab S.p.A. (Brindisi, Italy). Our overview is focused on their characterization, drawing a correlation between matrix structure, rheological and physicochemical properties related to their cross-linking technologies. (2) Methods: Four different injectable HA hydrogels were characterized through optical microscopic examination and rheological behavior investigation. (3) Results: The cross-linked HA dermal fillers showed a fibrous "spiderweb-like" matrix structure and an elastic and solid-like profile. (4) Conclusions: The comparative analysis represents a preliminary characterization of these injectable medical devices in order to identify their best field of application.

Physico-Chemical Characterization and In Vitro Biological Evaluation of a Bionic Hydrogel Based on Hyaluronic Acid and l-Lysine for Medical Applications.

Hyaluronic acid (HA) is an endogenous polysaccharide, whose hydrogels have been used in medical applications for decades. Here, we present a technology platform for stabilizing HA with a biocrosslinker, the amino acid L-lysine, to manufacture bionic hydrogels for regenerative medicine. We synthetized bionic hydrogels with tailored composition with respect to HA concentration and degree of stabilization depending on the envisaged medical use. The structure of the hydrogels was assessed by microscopy and rheology, and the resorption behavior through enzymatic degradation with hyaluronidase. The biological compatibility was evaluated in vitro with human dermal fibroblast cell lines. HA bionic hydrogels stabilized with lysine show a 3D network structure, with a rheological profile that mimics biological matrixes, as a harmless biodegradable substrate for cell proliferation and regeneration and a promising candidate for wound healing and other medical applications.

The Anti-Ageing and Whitening Potential of a Cosmetic Serum Containing 3-O-ethyl-l-ascorbic Acid.

Skin ageing has many manifestations such as wrinkles, dryness, hyperpigmentation, and uneven skin tone. Extrinsic and intrinsic factors, especially solar ultraviolet light (UVB), contribute to skin ageing; its main features are brown spots, alterations in melanin pigmentation, and a decrease in collagen and hyaluronic acid linked to oxidative stress. Several studies showed that topical products containing ingredients with antioxidant activity can reduce oxidative damage; to provide a maximum anti-ageing effect to the skin, topical products can combine various ingredients. C-SHOT SERUM contains a combination of two molecules with a proven anti-ageing activity: a high percentage (30%) of a more stable vitamin C derivative, 3-O-ethyl-l-ascorbic acid, and lactic acid (1%). The product showed a high biocompatibility, assessed through an MTT assay on keratinocytes and on Reconstructed Human Epidermis (RHE, SkinEthic); the anti-ageing activity was demonstrated on human dermal fibroblasts and keratinocytes by a statistically significant increase in collagen production and a reduction of a UVB-induced DNA damage marker (γ-H2AX histone), indicating DNA protection. Moreover, a depigmenting activity, shown by a highly significant decrease in melanin content on treated Reconstructed Human Pigmented Epidermis (RHPE), was assessed. According to the data of our study, the tested product contrasts the effect of skin ageing and irregular pigmentation due to the physiological decline of the skin.

Toward Physicochemical and Rheological Characterization of Different Injectable Hyaluronic Acid Dermal Fillers Cross-Linked with Polyethylene Glycol Diglycidyl Ether.

(1) Background: Injectable hyaluronic acid (HA) dermal fillers are used to restore volume, hydration and skin tone in aesthetic medicine. HA fillers differ from each other due to their cross-linking technologies, with the aim to increase mechanical and biological activities. One of the most recent and promising cross-linkers is polyethylene glycol diglycidyl ether (PEGDE), used by the company Matex Lab S.p.A., (Brindisi, Italy) to create the HA dermal filler PEGDE family. Over the last few years, several studies have been performed to investigate the biocompatibility and biodegradability of these formulations, but little information is available regarding their matrix structure, rheological and physicochemical properties related to their cross-linking technologies, the HA content or the degree of cross-linking. (2) Methods: Seven different injectable HA hydrogels were subjected to optical microscopic examination, cohesivity evaluation and rheological characterization in order to investigate their behavior. (3) Results: The analyzed cross-linked dermal fillers showed a fibrous "spiderweb-like" matrix structure, with each medical device presenting different and peculiar rheological features. Except for HA non cross-linked hydrogel 18 mg/mL, all showed an elastic and cohesive profile. (4) Conclusions: The comparative analysis with other literature works makes a preliminary characterization of these injectable medical devices possible.

In Vitro Evaluation of the Effect of a Not Cross-Linked Hyaluronic Acid Hydrogel on Human Keratinocytes for Mesotherapy.

The multicomponent preparations for mesotherapy are based on the principle that skin and hair aging can be prevented by supplying the fundamental substrates for correct cellular functioning, such as nucleotides, vitamins, amino acids, and biomolecules including hyaluronic acid (HA) that promote skin hydration and several biological activities. The study provides evidence for the application of HYDRO DELUXE BIO (Matex Lab S.p.A), a biocompatible hydrogel containing not cross-linked HA, for the treatment of the scalp's skin by mesotherapy. Using an in vitro model of immortalized human keratinocytes, we studied markers involved in hair aging prevention and growth, such as inflammatory markers, angiogenesis, and oxidative damage. HYDRO DELUXE BIO showed high biocompatibility and the ability to significantly reduce the expression of the inflammation marker interleukin (IL)-8 in Tumor Necrosis Factor (TNF)-stimulated cells. Then, we evaluated angiogenesis, a pivotal event during hair growth, measuring the Vascular Endothelial Growth Factor (VEGF) expression that resulted to be significantly increased in treated cells, suggesting a pro-angiogenetic capability. A protective activity against the oxidative stress agent was showed, increasing the survival rate in treated cells. Concluding, HYDRO DELUXE BIO is suitable for treatment by mesotherapy of the scalp's skin as it modulates the expression levels of markers involved in the biorevitalization of the hair follicle.

Biological Efficacy Evaluation of a Non-Cross-Linked Hyaluronic Acid Dermal Filler for Biomedical Application in Inflammatory Scalp Conditions.

(1) Background: The dysbiosis of some cutaneous commensal microorganisms is the trigger factor for the activation of the inflammatory cascade by keratinocytes in many skin disorders. Mesotherapy is an innovative technique for many scalp disorders, with the function of restoring the physiology of the skin. (2) Methods: the antimicrobial, antibiofilm and anti-inflammatory activity of the non-cross-linked HA formulation (Hydro Deluxe, Matex Lab S.p.a., Brindisi, Italy) was investigated against the most common microorganisms of the scalp (Staphyloccoccus epidermis, Staphyloccoccus aureus, Cutibacterium acnes and Malassezia furfur). Anti-inflammatory activity was evaluated on an internal 3D model of Reconstructed Human Epidermis (RHE) inserts infected with the strains as pro-inflammatory stimulus. (3) Results and Conclusions: the data collected showed a good antimicrobial and antibiofilm activity against all selected strains. The HA-based formulation did not show cytotoxicity on RHE, either alone or in presence of the infectious stimulus. The analysis of the expression of Interleukin (IL)-8 levels showed an excellent ability to reduce this pro-inflammatory marker. Overall, the efficacy assessment of the formulation supported its potential effectiveness in mesotherapy for the treatment of scalp disorders.