Sabrina Sommatis

Hyaluronic acid (HA) fillers represent the most frequently performed minimally invasive procedures for facial rejuvenation, yet their overall safety profile is critically influenced by the cross-linking technology employed. Polyethylene glycol diglycidyl ether (PEGDE) has recently been introduced as an alternative to 1,4-butanediol diglycidyl ether (BDDE). The present prospective observational study was undertaken to evaluate the safety of a PEGDE-crosslinked HA filler for the correction of severe nasolabial folds. A total of 60 patients received bilateral injections of 1 mL per side and were monitored over a six-month period. Safety assessment included systematic documentation of adverse events and non-invasive biophysical and imaging techniques, specifically corneometry, sebumetry, and high-frequency ultrasound (HFUS). The treatment was well tolerated: 15% of patients reported only mild and transient adverse events, such as pain, swelling, bruising, or discomfort, while no serious adverse events, vascular compromise, or ocular complications were observed. Corneometry demonstrated a statistically significant increase in cutaneous hydration, sebumetry confirmed stability of sebaceous activity, and HFUS documented correct placement, homogeneous distribution, and progressive integration of the filler without nodules or granulomatous reactions. These findings support the favorable short-term safety and local tolerance of PEGDE-crosslinked HA fillers in the treatment of severe nasolabial folds.

Recently, thanks to the greater discovery of the mechanisms of facial aging, an alternative to invasive plastic surgery has found space with less invasive aesthetic procedures, also based on an increasingly pressing request. We are specifically referring to dermal filler injection into or under the skin which leads to immediate rejuvenation and aesthetic improvements. In this study, we wanted to analyze the results obtained through the use of NEAUVIA Organic Stimulate, particularly with regard to its effectiveness, which is a cross-linked polymeric hydrogel, containing stabilized sodium hyaluronate 26 mg/mL and calcium hydroxyapatite (1%), glycine and L-proline in buffer pyrogen-free water, in its main indication, namely, the temporary correction of congenital and acquired deficiencies of the soft tissues of the face by intradermal injection. Initially, 70 patients were enrolled, but 10 did not complete the study due to non-observance of the investigation rules, so they were excluded from the protocol. The collected data demonstrate an efficient mechanical effect of the pegylated polymeric acid matrix enriched with low concertation of calcium hydroxyapatite and in accordance with other evidence in vitro and in vivo, and the mechanical support of the interstitial connective space improves the homestays of the anatomical layer rebalancing the physiological activity of the dermis cells.

Hyaluronic acid is one of the most important ingredients in dermal fillers, where it is often cross-linked to gain more favorable rheological properties and to improve the implant duration. Poly(ethylene glycol) diglycidyl ether (PEGDE) has been recently introduced as a crosslinker because of its very similar chemical reactivity with the most-used crosslinker BDDE, while giving special rheological properties. Monitoring the amount of the crosslinker residues in the final device is always necessary, but in the case of PEGDE, no methods are available in literature. Here, we present an HPLC-QTOF method, validated according to the guidelines of the International Council on Harmonization, which enables the efficient routine examination of the PEGDE content in HA hydrogels.

(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-βgal-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.

(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.

(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.

(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.

(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.

(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.

Physiological ageing due to the passing of time and prolonged exposure to harmful sun rays generate wrinkles and reduce skin elasticity. These visible and clinical signs can be prevented or reversed by known strategies, such as the daily use of cosmetic products with antioxidant combinations or retinoids. A new dermocosmetic formulation enriched with a complex of retinoids, called RETINOIDS SERUM, was investigated through in vitro assays using human skin cells. The experiments were carried out to assess the anti-ageing activity in normal human dermal fibroblasts (NHDF) and epidermal keratinocytes (HaCaT). After the preliminary MTT assay, the proliferation together with the synthesis of collagen and elastin fibers was performed on NHDF cells after 24 h treatment with the two non-cytotoxic concentrations. Using UVB-irradiated HaCaT cells, the measurement of matrix metalloproteinase-1 (MMP-1) levels was also investigated. In vitro studies show that the dermocosmetic product improves collagen and elastin synthesis and the renewal of dermal fibroblasts. Moreover, a reduction in the MMP-1 secretion was also highlighted in UVB-irradiated HaCaT cells. These results suggest that the cosmetic formulation containing functional compounds such as retinoids can be useful to prevent the natural sign of ageing.