Hyaluronic acid, known also as hyaluronan, is the most abundant glycosaminoglycan in the extracellular matrix. It is produced by most of the cells in the human body, possibly contributing to various fundamental biological processes. This prompts interest in its therapeutic value. Hyaluronic acid (HA) has been used for various treatments owing to its broad range of properties in medical and dental field specially in periodontology. The review gives an overview on the effects of HA on fibroblasts, bone, wound healing, periodontal regeneration, aphthous ulcer/stomatitis and stem cells. Outcomes of including Hyaluronic acid in non-surgical periodontal therapy, drug delivery system and surgical procedures such as root coverage, papilla regeneration, root conditioning, intrabony defects, guided tissue regeneration are rather optimistic. HA has shown astounding potential in treating periimplantitis. Newer frontiers have to be explored to comprehend the other promising properties of HA. Keyword – Hyaluronic Acid, Periodontology.

Development of bioresponsive extrudable hydrogels for 3D bioprinting is imperative to address the growing demand for scaffold design and efficient and reliable methods of tissue engineering and regenerative medicine. This study proposed genipin-crosslinked gelatin-hyaluronic acid hydrogel bioink with different amounts of gelatin tailored for 3D bioprinting, focusing on high cell density loading and less artificial extra-cellular matrix (ECM) effect, as well as exploring their potential applications in tissue engineering. The bioresponsiveness of these hydrogel scaffolds was successfully evaluated in different physiological conditions. 3D and four-axis printing of complex structures such as shapes of hollow tube, star, pyramid, and four-axis tubular scaffolds prove the hydrogel’s high extrusion ability and post-printing shape fidelity. Cytocompatibility and high cell density 3D bioprinting using this moderately stable hydrogel exhibit high potential for precise cell-delivery modes in tissue engineering as well as regenerative medicine.

This study investigated the potential of electrospun collagen/Hyaluronic Acid nanofibers in biomedicine and skincare. Needleless electrospinning technology employed in the production process resulted in nanofibers with consistent fiber diameters and improved mechanical properties. The composite nanofibers demonstrated impressive tensile strength and elongation capabilities, indicating a favorable interaction between collagen and HA. Cellular assays revealed that the collagen/HA scaffolds facilitated superior cell adhesion and proliferation compared to the control scaffolds, indicating their biocompatibility and potential for tissue engineering. This biomaterial offers an environment-friendly alternative to conventional skincare products by eliminating the need for preservatives and reducing waste. Although the initial costs are high, the long-term benefits of material durability and active ingredient efficacy provide a compelling case for industrial adoption. Our findings suggest that collagen/HA nanofibers have the potential to be next-generation materials for regenerative medicine and skincare, and further research is needed to optimize their production and assess the economic feasibility of skincare and tissue engineering applications.

The aim of this systematic scoping review was to provide scientific evidence on the efficacy and methods of application of hyaluronic acid in the coverage of gingival recessions in terms of recession depth (RD) reduction, clinical attachment level (CAL) gain, probing depth (PD). An electronic search of the literature on the main databases was conducted. Initially, 405 articles were identified. Finally, 4 studies were included after the review process. It was not possible to perform a meta-analysis of the articles selected because of the differences among the surgical treatments and commercial formulations and compositions of hyaluronic acid. Both randomized controlled trials in this research examined Recession Type 1 gingival treated with coronally advanced flap. Recessions were treated with either modified coronally advanced tunnel or laterally closed tunnel combined with subepithelial connective tissue graft and hyaluronic acid (HA) in all case series. The studies analyzed no significant variation was found in PD variable. The results of RD reduction are in accordance with the literature. Modifications of CAL are connected to variations of RD. HA seems to improve the clinical outcomes of the described surgical treatment.

Dental pulp tissue engineering (TE) quests to regenerate dentin/pulp complex by combining a suitable supporting matrix, stem cells, and biochemical stimuli. Such procedures foresee a matrix that can be easily introduced into the root canal system (RCS) and tightly adhere to dentin walls to assure the dentin surface's proper colonization with progenitor cells capable of restoring the dentin/pulp complex. Herein was investigated an injectable self-setting hyaluronic acid-based (HA) hydrogel system, formed by aldehyde-modified (a-HA) with hydrazide-modified (ADH), enriched with platelet lysate (PL), for endodontic regeneration. The hydrogels' working (wT) and setting (sT) times, the adhesion to the dentine walls, the hydrogel's microstructure, and the delivery of human Dental Pulp Cells (DPCs) were studied in vitro. Hydrogels incorporating PL showed a suitable wT and sT and a porous microstructure. The tensile tests showed that the breaking point occurs after 4.13 mm deformation. While in the indentation test after 1.3 mm deformation. Both breaking points occur in the hydrogel extension. The HA/PL hydrogels exhibited supportive properties and promoted cell migration toward dentin surfaces in vitro. Overall, these results support using PL-laden HA injectable hydrogels (HA/PL) as a biomaterial for DPCs encapsulation, thereby displaying great clinical potential towards endodontic regenerative therapies.

Macrophages are cells involved in the primary response to debris derived from wear of implanted CoCr alloys. The biocompatibility of wear particles from a high carbon CoCr alloy produced under polarization in physiological hyaluronic acid (HA) solution was evaluated in J774A.1 mouse macrophages cultures. Polarization was applied to mimic the electrical interactions observed in living tissues. Wear tests were performed in a pin-on-disk tribometer integrating an electrochemical cell in phosphate buffer solution (PBS) and in PBS supplemented with 0.3% HA, physiological synovial fluid concentration, used as lubricant solution. Wear particles produced in 0.3% HA solution showed a higher biocompatibility in J774A.1 macrophages in comparison to those elicited by PBS. A considerable improvement in macrophages biocompatibility in the presence of 0.3 % of HA was further observed by the application of polarization at potentials having current densities typical of injured tissues suggesting that polarization produces an effect on the surface of the metallic material that leads to the production of wear particles that are macrophages biocompatible and less cytotoxic. The results showed the convenience to consider electric interactions together with other particles parameters, as are size and composition, to get a better understanding of the biological effects of the wear products.

Osteoarthritis (OA) is a disease that currently has no cure. There are numerous studies showing that carnosine and hyaluronic acid (HA) have a positive pharmacological action during joint inflammation. For this reason, the goal of this research was to discover the protective effect of a new HA+Carnosine formulation (FidHycarn) on the inflammatory response and on the cartilage degradation in in vivo experimental model of OA. This model was induced by a single intra-articular (i.ar.) injection of 25µl normal saline having 1mg of monosodium iodoacetate solution (MIA) in the knee joint. MIA injection caused histological alterations and degradation of cartilage as well as behavioral changes. Oral treatment with FidHycarn ameliorated the macroscopic signs, improved thermal hyperalgesia and weight distribution of hind paw as well as decreased histological and radiographic alterations. The oxidative damage was analyzed by evaluating the levels of nitrotyrosine and inducible nitric oxide synthase (iNOS) that were significantly reduced in FidHycarn rats. Moreover, the levels of pro-inflammatory cytokines and chemokines were also significantly reduced by FidHycarn. However, interestingly, in more cases, the effects of FidHycarn were not statistically different to Naproxen used as positive control. Thus, the new formulation containing Carnosine and HA could represent an interesting therapeutic strategy to combat osteoarthritis.

Background: Hyaluronic acid (HA) is well known in the cosmetic industry for its hydrating properties linked to its interaction with keratin in the stratum corneum. Hair is also mainly composed of keratin, but no evidence of penetration and interaction of HA in hair had yet been established. Herein, we examined, with appropriate methods, this penetration and interaction. Methods: Confocal Raman Spectroscopy was used to track HA penetration in hair fibers. Human hair was UV-irradiated, or not, before washing with a number of different shampoo formulations. Low-molecular weight hyaluronic acid, high-molecular weight HA, and an optimized blend of low- and high-molecular weight HA, were used. The benefits of HA for cosmetic application were then evaluated at the ex vivo level. Results: Raman analysis of non-irradiated samples revealed that the HA blend penetrated the hair cortex 5.9 times more than the placebo and with irradiated samples, a 1.8-fold increase in penetration was observed. Whatever the irradiation status, penetration of this optimal HA blend was significantly greater than that of the other two active substances. Compared to the placebo, the HA blend significantly decreased spontaneous frizzing by 11%, repaired the hair by increasing the elastic modulus and the break force, and increased the water content in the hair shafts. Conclusion: Confocal Raman Spectroscopy can be considered as a powerful, non-invasive technique to investigate the penetration of active ingredients into the hair.

Musculoskeletal disorders are increasingly prevalent worldwide, causing significant socioeconomic burdens and diminished quality of life. Notably, patellar chondropathy (PC) is among the most widespread conditions affecting the joint structures, resulting in profound pain and disability. Hyaluronic acid (HA) and platelet-rich plasma (PRP) have emerged as reliable, effective, and minimally invasive alternatives. Continuous research spanning from laboratory settings to clinical applications demonstrate the numerous advantages of both products. These encompass lubrication, anti-inflammation, and stimulation of cellular behaviors linked to proliferation, differentiation, migration, and the release of essential growth factors. Cumulatively, these benefits support the rejuvenation of bone and cartilaginous tissues, which are otherwise compromised due to the prevailing degenerative and inflammatory responses characteristic of tissue damage. While existing literature delves into the physical, mechanical, and biological facets of these products, as well as their commercial variants and distinct clinical uses, there is limited discussion on their interconnected roles. We explore basic science concepts, product variations, and clinical strategies. This comprehensive examination provides physicians with an alternative insight into the pathophysiology of PC as well as biological mechanisms stimulated by both HA and PRP that contribute to tissue restoration.

The absence of interdental papillae leads to the appearance of black triangle. For most patients, the appearance of these triangles is an important reason for concern and affects their social relationships. Multiple reconstruction techniques have been developed with different degrees of success and predictability. The main aim of this study was to evaluate the efficiency of hyaluronic acid (HA) injected into interproximal papillae six months after injection and to perform a systematic review and meta-analysis. After a systematic review, five articles were selected: a clinical randomised controlled trial and four clinical trials. In total, eighty-five patients with a deficiency in upper papillae in the front of the maxilla and jaw were included in the study. The height variable was evaluated (mm) six months after HA injection. In total, one hundred and four interproximal papillae were studied. Three articles showed an important difference in favour of intervention. The total result regarding in the injection of AH was favourable with an approximate average filling of 0.7 mm in the height of the interdental papilla. The injection of HA for the reconstruction of deficient papillae in the region of the upper and lower maxilla was a possible option treatment strategy.

Diseases in articular cartilages have affected millions of people globally. Although the biochemical and cellular composition of articular cartilages is relatively simple, there is the limitation in self-repair ability of cartilage. Therefore, developing the strategies for cartilage repair is very important. Here, we reported a new manufacturing process of water-based polyurethane based photosensitive materials with hyaluronic acid and applied the materials for 3D printed customized cartilage scaffolds. The scaffold has high cytocompatibility and is one that closely mimics the mechanical properties of articular cartilages. It is suitable for culturing human Wharton's jelly mesenchymal stem cells (hWJMSCs) and the cells showed an excellent chondrogenic differentiation capacity. We consider that the 3D printing hybrid scaffolds may have potential in customized tissue engineering and facilitate the development of cartilage tissue engineering.

The ultrasound guided viscosupplementation of the hip joint with hyaluronic acid(HA)is considered a standard procedure among the conservative treatments for hip arthritis.The aim of the study was to evaluate the clinical benefit and the incidence of adverse events of the technique in a obseravtional study at one year follow up. We evaluated a consecutive series of 85 patients with a diagnosis of symptomatic arthritis that performed intra-articular ultrasound-guided hyaluronic acid injections. The scales used for evaluation were modified Harris Hip Score(mHHS),WOMAC (Western Ontario and McMaster University),Hip Outcome Score (HOOS) with subscale Sport (HOOSs), for pain the Visual Analogic Scale (VAS).The patients were classified according to Tonnis’ radiological classification of arthrosis (range 0-3):20 patients(grade 0),32(grade 1),18(grade 2),15(grade 3).At last follow up all the scales increased:mHHS from 59.35 to 82.1,HOOS from 69.45 to 78.53,HOS Sport from 47.4 to 58.11,VAS from 6.09 to 3.97,WOMAC from 33.2 to 31.5 (p<0.05 for all the parameters);13/85 requested arthroplasty. Based on our findings, indication for use of hyaluronic acid is limited to patients with mild to moderate arthritis.Patients in advanced arthritis refusing replacement surgery and asking for this treatment should be informed about the poor results of the technique even in the short term follow up.

Accelerated degradation of collagen membranes (CMs) in diabetic rats is associated with increased infiltration of macrophages and blood vessels. Since pre-implantation immersion of CMs in cross-linked high molecular weight hyaluronic acid (CLHA) delays membrane degradation, we evaluated its effect on the number of macrophages and endothelial cells (ECs) within the CM. Diabetes was induced with streptozotocin in 16 rats, while 16 healthy rats served as control. CM discs were labeled with biotin, soaked in CLHA or PBS and implanted under the scalp. Fourteen days later, CMs were embedded in paraffin and the number of macrophages and ECs within the CMs was determined using antibodies against CD68 and Transglutaminase II, respectively. Diabetes increased the number of macrophages and ECs within the CMs (∼2.5-fold and 4-fold, respectively). Immersion of CMs in CLHA statistically significantly reduced the number of macrophages (p<0.0001) in diabetic rats, but not that of ECs. In the healthy group, CLHA had no significant effect on the number of either cells. Higher residual collagen area and membrane thickness in CLHA-treated CMs in diabetic animals were significantly correlated with reduced number of macrophages but not ECs. Immersion of CM in CLHA inhibits macrophage infiltration and reduces CM degradation in diabetic animals.

Knee osteoarthritis (KOA) is a progressive and multifactorial disease that leads to joint pain, muscle weakness, physical disability, and decreased quality of life. In KOA, hyaluronic acid (HA) quantity and molecular weight (MW) are decreased, leading to joint pain due to increased wear of the knee articular cartilage. Arthrogenic muscle inhibition, which is usually found in patients with KOA, is associated with joint inflammation, pain, and swelling, also causing muscle atrophy, primarily of the anterior thigh muscles, and hindering the rehabilitation process. The aim of our work was to determine if a single HA infiltration could minimize the effects of arthrogenic muscle inhibition in patients with KOA in the short term, using isokinetic dynamometry to evaluate the strength of the knee extensor and flexor muscles of the thigh. Thirty patients with KOA who underwent both clinical and isokinetic assessment, and that received a single injection of HA, were retrospectively included. Our results showed that a single intra-articular injection of HA significantly reduces pain and improves joint function at four weeks, while non-statistically significant improvements were observed for the reference isokinetic parameter (maximum torque) at both 90°/s and 180°/s. Further high-quality studies are necessary to confirm the results of our study.

Polyelectrolyte-drug complexes are interesting alternatives to improve unfavourable drugs properties. Vancomycin (VAN) is an antimicrobial used in the treatment of methicillin-resistant Staphylococcus aureus pulmonary infections in patients with cystic fibrosis. It is generally administered intravenously with high incidence of adverse side effects, which could be reduced by intrapulmonary administration. Currently, there are no commercially available inhalable formulations containing VAN. Thus, the present work focuses on the preparation and characterization of an ionic complex between hyaluronic acid (HA) and VAN with potential use as inhalable formulations. Particulate-solid HA-VAN25 complex by spray drying from an aqueous dispersion was obtained. FTIR spectroscopy and thermal analysis confirmed the ionic interaction between HA and VAN, while an amorphous diffraction pattern by X-ray was observed. The powder density, geometric size and morphology showed a suitable aerosolization and aerodynamic performance of the powder, indicating the capability of reaching the deep lung. An in vitro extended-release profile of VAN from the complex was obtained, exceeding 24 hours. Microbiological assays against methicillin-resistant and -sensitive reference strains of Staphylococcus aureus, showed that VAN preserves its antibacterial efficacy. In conclusion, HA-VAN25 exhibited interesting properties for the development of inhalable formulations with potential efficacy and safety advantages over conventional treatment.

Since its first isolation in 1934, hyaluronic acid (HA) has been studied across a variety of research areas. This unbranched glycosaminoglycan consisting of repeating disaccharide units of N-acetyl-D-glucosamine and D-glucuronic acid is almost ubiquitary in humans and in other vertebrates. HA is involved in many key processes -including cell signaling, wound reparation, tissue regeneration, morphogenesis, matrix organization and pathobiology-, and has unique physico-chemical properties -such as biocompatibility, biodegradability, mucoadhesivity, hygroscopicity and viscoelasticity. For these reasons, exogenous HA has been investigated as drug delivery system and treatment in cancer, ophthalmology, arthrology, pneumology, rhinology, urology, aesthetic medicine and cosmetic. To improve and customize its properties and applications, HA can be subjected to chemical modifications: conjugation and crosslinking. The present review gives an overview regarding HA, describing its history, physico-chemical, structural and hydrodynamic properties, and biology –occurrence, biosynthesis (by hyaluronan synthases), degradation (by hyaluronidases and oxidative stress), roles, mechanisms of action and receptors. Furthermore, both conventional and recently emerging methods developed for the industrial production of HA and its chemical derivatization are presented. Finally, the medical, pharmaceutical and cosmetic applications of HA and its derivatives are reviewed, reporting examples of HA-based products which currently are on the market or are undergoing further investigations.

Objectives: To rate the effects of low molecular weight hyaluronic acid (LMWHA) solution and high concentration oxygen (HCO) through a specific medical device (Caress Flow©), compared to topical administration of hyaluronic acid (HA) alone on symptoms of mild and moderate stress and mixed urinary incontinence in women with genitourinary syndrome of menopause (GSM). Methods: A total of 68 postmenopausal women were enrolled (from October 2021 to September 2023). Patients were separated in two groups: one group used therapy with LMWHA solution and HCO combined and the second group used therapy with HA alone. Patient Global Impres-sion of Improvement (PGI-I) as the first outcome was used. As secondary outcomes International Consultation on Incontinence Questionnaire - short form (ICIQ-SF) questionnaire and Internation-al Quality of Life (IQoL) questionnaire were used. Results: Sixty-eight (68) women, 35 (51%) and 33 (49%), were treated with LMWHA solution and HCO combined and HA alone for 10 weeks, respectively. 28 (80%) versus 7 (20%) women reported an improvement (PGI-I score ≤3) of the symptoms in LMWHA solution and HCO com-bined group versus HA alone group. According to the ICIQ-SF, a statistically significant differ-ence was recorded after treatment between the two groups (median, 7 [5-11] vs 10 [8-11]; P = 0.03). According to the IQoL questionnaire, a statistically significantly lower median score was recorded in the LMWHA solution and HCO combined compared with the HA group, before (71 [IQR 55-81] vs 89 [IQR 67-94]; P < 0.01) and after (78 [IQR 65-86] vs 88 [IQR 72-99]; P = 0.04) treatment. Conclusions: LMWHA solution and HCO combined might improve the mild and moderate stress and mixed urinary incontinence in this set of women and that it is superior to HA therapy alone. However, these results need to be confirmed in further studies with a controlled design and a larger population.

Dermal injections of hyaluronic acid gel for aesthetic skin rejuvenation are increasingly popular nowadays. Although these products are classified as medical devices, the regulations on their administration by licensed practitioners are still weak, whereas their manufacturers increasingly highlight and advertise the cellular effects that underpin the efficacy of these injections. In this re-view, we discuss all current knowledge on the mode of action of dermally injected hyaluronic acid and the potential toxicological implications especially from crosslinked gels in conjunction with the current global regulations. We conclude that dermal injections of hyaluronic acid have several therapeutic implications that warrant further research, and that strict regulations must be applied on their manufacture/quality control and the required qualifications of licensed aesthetic injectors.

Knee Osteoarthritis (KOA), the most common knee degenerative disease, involve a slow destructive process, leading to disability and ultimately total knee replacement. The progression of KOA is related to the loss of rheological properties of the synovial fluid (SF), due to slow immunological, inflammatory and enzymatic processes that cleave the hyaluronic acid (HA) and decrease the concentration of specific proteins. Since no effective treatments have been found to halt the progression of KOA, injection of HA-based viscoelastic gels combined with physiotherapy (PT) is an alternative to symptomatic therapies. In order to evaluate the effect of viscosupplementation and PT on the SF characteristics, the SF aspirated from the KOA was spectrophotometrically and rheological analyzed, comparing the receiving groups of HA Kombihylan® and groups that received Kombihylan® and complex PT. In patients treated with PT, SF extracted 6 weeks after viscosupplementation had a superior elastic moduli (G') and viscous moduli (G") profile behavior, having a homogeneous distribution of proteins and polysaccharides in the SF, stimulating stronger interactions. In the absence of PT the G' and G" profiles are non-uniform, suggesting an unorganized supplemented SF with some clustering phenomena, proteins aggregation and a low level of entanglement between HA and macromolecular components in the SF.

Background: Knee osteoarthritis (OA) significantly affects quality of life and imposes economic burdens due to its prevalence and the disability it causes. The efficacy of current treatments is limited to alleviate the symptoms and not for regenerative purposes. This study aims to evaluate the efficacy and safety of combining hyaluronic acid (HA), human umbilical cord mesenchymal stem cells (hUC-MSCs), and synthetic human growth hormone (somatotropin) in the treatment of knee OA, assessing pain relief, functional improvement, and cartilage regeneration. Methods: A four-arm, double-blind randomized trial was conducted with 51 knees from 28 subjects, aged ≥ 50 with primary knee OA. Treatments involved are HA alone, HA with hUC-MSCs, HA with somatotropin, and a combination of all three. Efficacy was measured through the International Knee Documentation Committee (IKDC) score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and visual analog score (VAS) along with MRI T2 mapping of cartilage were taken on pre-implantation, 6th and 12th month. Results: All treatment arms showed improvement in VAS and WOMAC scores over 12 months, suggesting some pain relief and functional improvement. However, MRI T2 mapping showed no significant cartilage regeneration across the groups. Conclusion: While combined use of HA, hUC-MSCs, and somatotropin improved symptoms of knee OA, it did not enhance cartilage regeneration significantly. The study highlights the potential of these combinations for symptom management but underscores the need for further research to optimize these therapies for regenerative outcomes.

Hydrogels have gained significant attention as vehicles for transdermal delivery systems. These polymeric-structured substances have been implemented in pharmaceutical and cosmetic applications. Many factors are employed in their preparation. Light, pH, temperature and specific molecules ligands are commonly used in the production of hydrogels. The Transdermal delivery system (TDD) is a widely used route, used to deliver actives/drugs via the skin. Hydrogels as a TDD have been shown to be efficient in enhancing the efficacy in delivering the actives and drugs. The aim of this review is to discuss the hydrogels application in both dermatological therapeutic and cosmetic applications, covering the types, and properties of hydrogel polymer networks. Furthermore, this review presents one of the most extensively used polymers (Hyaluronic acid HA) in this field and discusses the properties, preparation methods and applications of HA hydrogel patches as a delivery system, including methods of loading the actives and the releasing of these actives from them.

Biphasic bone substitutes (BBS) are nowadays established biomaterials. Through their constant development even natural components like hyaluronic acid (HY) are added to improve both their handling and also their regenerative properties. However, low knowledge exists regarding the consequences of the HY addition for their biocompatibility and the inflammatory tissue reactions. Thus, the present study was conducted aiming to analyze the influence of two different amounts of high molecular weight HY (HMWHY) combined with a BBS on the in vitro biocompatibility and the in vivo tissue reaction. Established in vitro procedures using L929 cells were used for cytocompatibility analyses under the test conditions of DIN EN:ISO 10993-5. For the in vivo study part, calvarial defects were created in 20 Wistar rats and subsequently filled with the BBS and the BBS combined with two different HMWHY amounts, i.e., BBS+HY(L) and BBS+HY(H). As controls empty defects were used. Established histological, immunohistochemical and histomorphometrical methods were applied to analyze the tissue reactions to the three different materials, including the induction of pro- and anti-inflammatory macrophages and multinucleated giant cells (BMGCs). The in vitro results showed that none of the materials or compositions caused biological damages to the L929 cells and can considered to be non-toxic. The in vivo results showed that only the addition of high doses of HY to a biphasic bone substitute significantly decreases the occurrence of proinflammatory macrophages (* p < 0.05) comparable to the numbers found in the control group, while no significant differences within the three study groups for M2-macrophages nor BMGCs were detected. In conclusion, the addition of different amounts of HMWHY does not seem to affect the inflammation response to the BBS while improving the material handling properties.

Background and Objectives: Mucilaginous substances from plant extracts are known to be able to support the lubricating effect of hyaluronic acid (HA) in dry eye disease (DED). In this pilot study, the combined lubricating effect of HA and mallow extract (Malva sylvestris L.) in patients with DED was assessed. Materials and Methods: 20 patients at 5 ophthalmological practices in Italy were treated with eye drops, containing HA and mallow extract on the one hand, and with eye drops containing HA only, on the other hand, in a two-period crossover design. As primary endpoints, the tear film breakup time (TBUT), the reduction of lissamine green staining of the ocular surface (Oxford Scheme, OS), and the safety and efficacy assessment by the ophthalmologists were evaluated. As secondary variables, the patient symptom score, the ocular surface index (OSDI), and the satisfaction, preference and efficacy judgement by the patients were evaluated. All data were analysed descriptively in addition to an exploratory analysis of the target variables. Results: Both products were well tolerated. There were no statistically significant differences, with regard to the TBUT, OS and OSDI, between both treatments. Anyway, the efficacy and safety assessments by the ophthalmologists and the patients showed results in favour of the combined product. Conclusion: The addition of mallow extract to HA containing eye drops enhances the treatment of DED at least with respect to subjective measurements. Further assessments will have to be done to prove and explain this observation in terms of measurable parameters, e.g. markers for inflammatory cytokines.

A face serum composed of a combination of biologically active compounds was evaluated for safety and efficacy in vitro, in a repeat insult patch test and in a human clinical efficacy trial. The serum inhibited tyrosinase activity modestly, decreased collagenase activity and exhibited notable free radical scavenging activity in vitro. It is gentle to the skin, as the serum did not irritate the skin or produce symptoms of allergic contact dermatitis in the 55 healthy adults that participated in the repeat insult patch test. In the efficacy trial, daily application of the face serum for 30 days significantly increased skin hydration, with all 35 volunteers experiencing improvement. Substantial improvements in skin elasticity, roughness (fine lines and wrinkles), and brightness also occurred during the trial. Dermatological examination also revealed a trend for reduced comedone count with use of the serum. Self-assessment responses revealed that all volunteers experienced improvements in multiple skin quality parameters and that participant perceptions are consistent with the results of the instrumental analyses. These findings indicated that the measured improvements in skin quality are not only statistically significant but are also clinically relevant as they were great enough for users of the face serum to feel and recognize.

The objective of this study was to compare single-needle arthrocentesis with the conventional two-needle arthrocentesis, as well as, additional intracapsular injection of hyaluronic acid or platelet rich fibrin. 96 patients with established osteoarthritis (OA) (n= 48) or with internal de-arrangement (DD) (n= 48) were assigned for single-needle arthrocentesis with distension of the joint or conventional two-needle arthrocentesis with or without intracapsular injection of the medication (hyaluronic acid- HA or platelet-rich plasma- PRP) performed every month in the period of 6 months. The maximum mouth opening and pain as measured by the visual analog scale (VAS) were compared. Each group exhibited significant improvement: decrease of pain and in-creased mouth opening. Single- puncture technique provided similar pain reduction as two needle approach but provided significantly better results in maximum mouth opening. Reduction of pain was similar when comparing between the OA and DD cohorts, however patients with disc dis-placement reached significantly better mouth opening than OA. Intracapsular application of medication contributed to significant decrease of pain in both HA and PRP groups, with plate-let-rich fibrin being significantly superior in terms of mouth opening increase over HA.

BackgroundAdvanced radiological stage of knee osteoarthritis (OA) and obesity are predictive of poorer and shorter response to viscosupplementation, but very few is known regarding the impact of other factors such as sport practice, comorbidities or anatomical features of OA. ObjectivesTo investigate the patient’s and OA characteristics associated with the duration of effectiveness (DE) of viscosupplementation in patients with knee OA.MethodsCross-sectional single center trial in patients with knee OA treated with intra-articular (IA) hyaluronic acid (HA) injection(s) within the previous 3 years. The investigator collected demographic and radiographic data (Kellgren grade, involved knee compartments), dosing regimen (single or repeat injections), presence and volume of joint effusion, previous or concomitant IA corticosteroid injection, number of previous viscosupplémentations and the comorbidities. The patient completed a questionnaire including the self-assessment of DE (number of weeks during which viscosupplementation was effective on symptoms), the activity level (sedentary, active, athletic), the level of sport activity (light, moderate or intensive). Predictors of DE were studied in univariate and multivariate analyses ResultsOne hundred five patients (149 knees) were analyzed (62% women, mean age 66.1 ± 13.2 years, mean BMI 27.5 ± 7.5 kg/m²). The mean DE was 48.2 + 24.8 weeks. In a bivariate analysis, the predictors of a shorter with DE were BMI >27.5kg/m2, more than 3 previous viscosupplémentations, Kellgren grade 4, sedentary patients, and more than 1 affected compartment. In the multivariate analysis, 4 independent factors remained associated with a shorter DE: BMI >27.5 kg/m2, knee multi-compartment damage, number of viscosupplements >3, sedentary lifestyle. A statistically significant association between a longer DE and treated arterial hypertension was found suggesting a beneficial effect of certain antihypertensive drugs. ConclusionThe study confirms the harmful influence of an increased BMI, It also shows that viscosupplementation is more effective in unicompartmental OA. Other points worth highlighting are the reduction in the duration of efficacy with repeated cycles of injections and the benefit of a regular physical activity.

(1) Background:A BMI &gt; 25 is the most decisive, albeit modifiable,risk factors for knee osteoarthritis (OA). This study aimed at assessing the efficacy of intra-articular injections of hybrid hyaluronic acid (HA) complexes (Synovial® H-L)for the treatment of kneeOA in overweight patientsin terms ofdisease severity, cardiocirculatory capacity, and quality of life. (2) Materials: In this single-site, open-label, prospective trial, 37 patients with symptomatic knee OA were assessed at baseline and 3 months after ultrasound-guided intra-articular injection of hybrid HA complexes (Synovial® H-L). (3) Results: Primary variables displaying a statistically significant improvement after treatment were pain (NRS), disease severity (WOMAC), and cardiopulmonary capacity a(6-Minute Walk Test). Among secondary variables, quality of life (SF-12) improved significantly, as did analgesic intake for pain control. No statistically significant difference was observed in body fat and muscle mass percentage measured by bioelectrical impedance analysis. (4) Conclusions:Intra-articular hybrid HA injections are significantly effective in improving OA-related disease severity, cardiopulmonary function, and analgesic intake. This supports the role of hybrid HA viscosupplementation as a non-pharmacological treatment to relieve pain, reduce disability and improve quality of life, and limit the risk of polypharmacy in overweight patients with knee OA.

Idiopathic pulmonary fibrosis (IPF) is one of the most common forms of interstitial lung disease characterized by progressive parenchymal fibrosis and respiratory failure. In a model of bleomycin-induced pulmonary fibrosis, the antifibrotic and anti-inflammatory activity of Longidaza (bovhyaluronidase azoxymer), which contains a conjugate of the hyaluronidase enzyme with a high molecular weight synthetic carrier azoxymer bromide, was investigated. Experiments were conducted in male C57BL/6 mice. Longidaza was administered at different doses by intranasal and intramuscular routes. Histology, hematology and enzyme-linked immunosorbent assay were used in the study. The use of Longidaza reduced pulmonary fibrosis as evidenced by an improvement in histopathologic damage to the lungs, a decrease in the area of connective tissue and the levels of profibrotic factors (TGF-β1, hydroxyproline, collagen I) in lung tissue. In addition, Longidaza inhibited the inflammatory response in pulmonary fibrosis, decreased the levels of IL-6, TNF-α, hyaluronic acid in lung tissue and the recruitment of inflammatory cells into lung tissue. The highest therapeutic efficacy was observed with the use of Longidaza at doses of 120 and 1200 U/kg intramuscularly, which was superior to that of the reference drug pirfenidone axunio. The data presented in this study suggest that Longidaza is a new and promising drug for the treatment of IPF that warrants further investigation in patients with fibrotic interstitial lung disease.

In osteoarthritis (OA), oxidative stress plays a crucial role in maintaining and sustaining cartilage degradation. Current OA management requires a combination of pharmaceutical and non-pharmacological strategies, including intraarticular injections of hyaluronic acid (HA). However, several lines of evidence reported that HA oxidation by reactive oxygen species (ROS) is linked with HA cleavage and fragmentation, resulting in reduced HA viscosity. Resolvin D1 (RvD1) is a lipid mediator that is biosynthesized from omega-3 polyunsaturated fatty acids and is a good candidate with the potential to regulate of panoply of biological processes, including tissue repair, inflammation, oxidative stress, and cell death in OA. Herein, newly designed, and synthesized imidazolium RvD1 analogues were introduced to compare their potential antioxidant properties with commercially available RvD1. Their antioxidant capacities were investigated by several in vitro chemical assays including Oxygen Radical Absorbance Capacity, 2,2-Diphenyl-1-picrylhydrazyl Radical Scavenging, Ferric Ion Reducing Antioxidant Power, Hydroxyl Radical Scavenging, and HA Fragmentation Assay. All results proved that imidazolium RvD1 analogues showed excellent antioxidant performance compared to RvD1 due to their structural modifications. Interestingly, they scavenged the formed reactive oxygen species (ROS) and protected HA from degradation, as verified by agarose gel electrophoresis and gel permission chromatography. A computational study using Gaussian 09 with DFT calculations and B3LYP/6-31 G (d, p) basis set was also employed to study the relationship between the antioxidant properties and chemical structures as well as calculation of the molecular structures, frontier orbital energy, molecular electrostatic potential, and bond length. The results showed that the antioxidant activity of our analogues was higher than that of RvD1. In conclusion, the findings suggest that imidazolium RvD1 analogues can be good candidates as antioxidant molecules for the treatment of oxidative stress-related diseases like OA. Therefore, they can prolong the longevity of HA in the knee and thus may improve the mobility of the articulation.

Melanoma is a malignant, highly metastatic neoplasm showing increasing morbidity and mortality. Tumor invasion and angiogenesis are based on remodeling of the extracellular matrix (ECM). Selective inhibition of functional components of cell-ECM interaction, such as hyaluronic acid (HA), matrix metalloproteinases (MMPs), and integrins, may inhibit tumor progression and enhance the efficacy of combination treatment with checkpoint inhibitors (ICBs), chemotherapy, or immunotherapy. In this review, we have combined the results of different approaches targeting extracellular matrix elements in melanoma in preclinical and clinical studies. The identified limitations of many approaches, including side effects, low selectivity and toxicity, indicate the need for further studies to optimize therapy. Nevertheless, significant progress in expanding our understanding of tumor biology and the development of targeted therapies holds great promise for the early approaches developed several decades ago to inhibit metastasis through ECM targeting.

Platelet and fibrin-rich orthobiologic products, such as autologous platelet concentrates, have been extensively studied and appreciated for their beneficial effects in multiple conditions. PRP and its derivatives, including PRF, have demonstrated encouraging outcomes in clinical and laboratory settings, particularly in the treatment of musculoskeletal disorders such as OA. Although PRP and PRF have distinct characteristics, they share similar properties. The relative abundance of platelets, peripheral blood cells and molecular components in these orthobiologic products stimulate numerous biological pathways. These include inflammatory modulation, augmented neovascularization, and delivery of pro-anabolic stimuli that regulate cell recruitment, proliferation, and differentiation. Furthermore, the fibrinolytic system, which is sometimes overlooked, plays a crucial role in musculoskeletal regenerative medicine by regulating proteolytic activity and promoting the recruitment of inflammatory cells and MSCs in areas of tissue regeneration, such as bone, cartilage, and muscle. PRP acts as a potent signaling agent; however, it diffuses easily, while the fibrin from PRF offers a durable scaffolding effect that promotes cell activity. The combination of fibrin with hyaluronic acid, another well-studied orthobiologic product, has been shown to improve its scaffolding properties, leading to more robust fibrin polymerization. This supports cell survival, attachment, migration, and proliferation. Therefore, the administration of the "power mix" containing HA and autologous PRP + PRF may prove to be a safe and cost-effective approach in regenerative medicine.

Hyaluronic acid, in the form of a gel or viscoelastic colloidal solution, is currently used for viscosupplementation of joints affected by osteoarthritis, but its effectiveness is under debate in relation to newer alternatives. Based on meta-analytical arguments, the present article reinforces the opinion that there are still no decisive arguments for its complete replacement, but for its use adapted to the peculiarities of the disease manifestation and of the patients. A “broad” comparison is first made with almost all alternatives studied in the last decade, and then a meta-regression study is performed to compare and predict the effect size induced by viscosupplementation and platelet-rich plasma therapies. If they are computerized, the developed models can represent tools for clinicians in determining the appropriateness of the option or not for viscosupplementation, in a manner adapted to the pain felt by the patients, to their age, or to other clinical circumstances. The models were generated using the latest algorithms for meta-analysis and meta-regression implemented in the R language and assembled in different R packages. All primary data and necessary R scripts are provided in accordance with the philosophy of reproducible research. Finally, HA-based products, currently under circumspection, are still clinically useful.

Crustacean hyaluronidases are 1 poorly understood both in terms of their enzymatic properties and in terms of their structural features. In this work, we have shown that the hepatopancreas homogenate of the red king crab has a hyaluronidase activity that is an order of magnitude higher than its commercial counterpart. Zymography revealed the hyaluronidase activity of the protein roughly from40 to 50 kDa relative to the molecular marker used in electrophoresis. Analysis of the hepatopancreas transcriptome revealed a hyaluronidase sequence with an expected molecular weight of 42.5 kDa. It turned out that the reaction of cleavage of hyaluronate in the presence of a homogenate proceeds by the mechanism of b-elimination, which is well known for bacterial hyaluronidases. Thus, a new hyaluronidase of higher eukaryotes was found and described, which is not integrated into the modern classification of hyaluronidases.

This study focused on hydrolysis of cosmetic fillers hyaluronic acid (HA) and kinetics of the HA hydrolysis using the homogenate of the red king crab hepatopancreas. Turbidimetric analysis of the reaction mixture revealed a bell-shaped time dependence of aggregation formation. It was shown that the obtained homogenate has the similar activity to the commercially available hyaluronidase. The atomic force microscopy (AFM) examination found that the HA fillers were represented by spherical-like structures. These structures were destroyed under the action of the homogenate of the red king crab hepatopancreas. NMR of the reaction mixture showed that HA degradation lasts for some days, but a maximum rate of the reaction is detected in the first hours of incubation. The preparation with hyaluronidase activity obtained from the red king crab hepatopancreas could be used as potentially safe product for treating filler complications.