High Concentration Of Hyaluronic Acid Research Articles

P-195 Euploid embryo transfer in a hyaluronic acid-enriched media results in a higher ongoing pregnancy rate than euploid embryo transfer in media not containing hyaluronic acid

Abstract Study question Will using a hyaluronan-rich transfer medium increase the ongoing pregnancy rate and live birth rate when transferring euploid embryos cultivated in a dry incubator? Summary answer Transferring euploid embryos in a media with high concentrations of hyaluronic acid increases the ongoing pregnancy rate compared with media with no hyaluronic acid. What is known already Cochrane Review found that solutions with high concentrations of hyaluronic acid increase the chance of live birth by adding probably 1 additional live birth for every 14 embryos transferred in a high-concentration hyaluronic acid solution for patients aged 27 to 35. A study involving 85 frozen embryo transfer cycles showed a positive effect of high concentrations of hyaluronic acid on the results of transfer of morphologically poor euploid blastocysts. Previous studies were conducted in humidified incubators where hyaluronic acid-rich media was equilibrated without oil overlay. Our clinic uses dry incubators, necessitating oil overlay with all media, including hyaluronic acid-rich media. Study design, size, duration A randomized prospective study involving 255 patients aged 19-44 undergoing a transfer of a single euploid embryo between June 2023 and November 2023. Patients were randomly assigned to the study and control groups. Blastocysts were incubated after thawing for 3 hours either in a hyaluronic acid-enriched medium or in a medium without hyaluronic acid. Participants/materials, setting, methods Embryos underwent PGT-A at the blastocyst stage on either day 5 or day 6, using the EmbryoMap method. Trophectoderm biopsy was performed using the Flicking technique without a laser. 5-7 cells were removed for analysis. Blastocysts were vitrified following biopsy. Hyaluronic acid-enriched media was equilibrated for 16-18 hours in a 5%O2 6%CO2 atmosphere in a well of 4-well culture dish under oil overlay (600 microliters of media and 500 microliters of oil). Main results and the role of chance In this ongoing study, 127 transfers of euploid blastocysts in a hyaluronic acid-rich media resulted in 70 ongoing pregnancies, with a 55.1% ongoing pregnancy rate. In comparison, 128 transfers of euploid blastocysts in a media with no hyaluronic acid resulted in 65 ongoing pregnancies, with a 50.8% ongoing pregnancy rate. The relative improvement in the ongoing pregnancy rate is 8.5%. Our data suggests that using a hyaluronic acid-rich medium for the transfer of euploid blastocysts of good morphology can improve clinical pregnancy rates, although the effect is less dramatic than was shown in a 2023 study by Nakagawa et al. for morphologically poor euploid blastocysts, where more than twofold increase in clinical pregnancy rates was detected. Limitations, reasons for caution Specific media equilibration protocol is required for the incubation and transfer of embryos in a hyaluronan-rich transfer medium for IVF clinics utilizing dry incubators. Further research is required to confirm results and to establish whether transferring embryos in hyaluronic acid-enriched media increases the live birth rate after euploid embryo transfer. Wider implications of the findings Our results show that it is feasible to use a hyaluronic acid-enriched medium in a dry incubator with an oil overlay and that using it according to described protocol could increase the ongoing pregnancy rate after a single euploid blastocyst transfer. Trial registration number not applicable

P-159 The role of Embryo transfer medium containing high concentrations of hyaluronic acid on IVF outcome: A systematic review and meta-analysis

Abstract Study question Does embryo transfer medium containing high concentrations of hyaluronic acid (HA) increase In Vitro Fertilisation (IVF) success rate? Summary answer Embryo transfer medium containing high concentration of HA has increased the live birth (LBR) and clinical pregnancy rate (CPR) whilst decreasing the miscarriage rate. What is known already The recent Cochrane systematic review reported low to moderate evidence to support the use of high concentration hyaluronic acid (HA) in the treatment group. Previous studies have also shown no effect of high concentration HA on frozen embryo transfer (FET) rate and have identified the supplementation of the transfer media with HA to have no significance on adverse effect rate. Study design, size, duration A literature search was performed on three online databases: Ovid Medline, PsychInfo and Central Cochrane. 1162 citations were retrieved and after screening abstracts and titles 1099 citations were removed and a following 37 removed after screening full texts. This left 26 publications for the review. Bias was assessed for in RCTs using Cochrane collaboration tool of bias and STROBE for observational studies. Meta-analysis was performed using Review manager identifying the risk ratio (RR) and heterogeneity. Participants/materials, setting, methods In the review, 6304 participants in the treatment group and, 5965 in the control group were included. The primary outcomes was LBR and secondary outcomes were CPR; miscarriage rate; multiple pregnancy rate; ectopic pregnancy and congenital abnormalities. A subgroup analysis was performed looking into the outcome based on the stage of embryos transferred, the exposure time to the transfer medium and difference between frozen and fresh embryo transfer. Main results and the role of chance There was a significant increase in LBR (RR: 1.25; 95% CI 1.17 to 1.33) with use of high concentration HA and this positive effect was seen in both cleavage stage and blastocyst transfer cycles. CPR was also higher (RR: 1.16 (95% CI 1.10 to 1.22), while Miscarriage rate was significantly reduced (RR: 0.75; 95% CI 0.66 to 0.85) in the treatment group. Multiple pregnancy rate were higher in the study group (RR: 1.33; 95% CI: 1.16 to 1.53), although one study had a large influence on these results. The ectopic pregnancy rates (RR: 0.62; 95% CI 0.19 to 1.99) and congenital abnormalities (RR: 0.84; 95% CI 0.37 to 1.92) were similar. On subgroup analysis, the higher LBR was seen only for fresh cycles (RR: 1.2; 95% CI 1.1 to 1.3) but were similar for frozen embryo transfer (RR: 0.99; 95% CI 0.8 to 1.24). Further, LBR were higher in both short (10 minutes) and long exposure (>10 minutes) groups (RR: 1.32; 95% CI 1.19 to 1.45 and RR: 1.23; 95% CI 1.14 to 1.33 respectively. Limitations, reasons for caution The high heterogeneity across the studies may increase the risk of bias in the results. Inclusion of observational studies also has an inherent risk of selection bias. The review did not have a restrictive exclusion criterion resulting in inclusion of patients from a large demographic, limiting the specificity of results. Wider implications of the findings The data from this review support the use of embryo transfer medium containing high concentration of HA during fresh IVF cycles but not for frozen cycles. However, a large RCT is warranted particularly for selected groups like women of advanced maternal age and those with recurrent implantation failure. Trial registration number Not applicable

A New Korean Highly Concentrated and Cohesive Hyaluronic Acid Gel: Global Facial Rejuvenation In 97 Brazilian Patients

Hyaluronic acid-based fillers are the most used dermal fillers today. Due to its safety, several types of products are on the market with different rheological properties. Recently a new Korean filler with high hyaluronic acid concentration was launched in Brazil. The rheological properties of this new filler caught our attention and encouraged its use for global facial rejuvenation. We report our clinical experience with these highly concentrated and cohesive hyaluronic acid gels, which have three different presentations according to the degrees of reticulation. All 97 patients had marked improvement sustained for at least six months of follow-up, with excellent patient satisfaction. Any significant side effect was noticed.

An Overview of Soft Tissue Fillers for Cosmetic Dermatology: From Filling to Regenerative Medicine.

Hyaluronic acid (HA)-based injectable filling agents are at the forefront of the current demand for noninvasive dermatological procedures for the correction of age-related soft tissue defects. The present review aims to summarize currently available HA-based products and critically appraise their differences in rheological nature and clinical application. Linear HA (LHA) gels may be supplemented with amino acids, lipoic acid, vitamins, nucleosides, or minerals for synergistic antiaging and antioxidant benefits (polycomponent LHA). HA hydrogels can be generated via chemical or physical crosslinking, which increases their elasticity and decreases viscosity. The performance of crosslinked fillers depends on HA concentration, degree of crosslinking, elastic modulus, cohesivity, and type of crosslinking agent employed. PEG-crosslinked LHA displays improved elasticity and resistance to degradation, and lower swelling rates as compared to BDDE-crosslinked LHA. Physical crosslinking stabilizes HA hydrogels without employing exogenous chemical compounds or altering hyaluronans’ natural molecular structure. Thermally stabilized hybrid cooperative HA complexes (HCC) are a formulation of high- and low-molecular-weight (H-HA and L-HA) hyaluronans, achieving high HA concentration, low viscosity with optimal tissue diffusion, and a duration comparable to weakly cross-linked gel. Our critical analysis evidences the importance of understanding different fillers’ properties to assist physicians in selecting the most appropriate filler for specific uses and for predictable and sustainable results.

Evaluation of the Lubricating Effect of Hyaluronic Acid on Contact Lenses Using a Pendulum-Type Friction Tester Under Mimicking Physiological Conditions.

Objective:To evaluate the lubricating effect of hyaluronic acid (HA) on soft contact lenses (SCLs) measured using a pendulum-type friction tester.Methods:We measured the coefficient of friction (CoF) of narafilcon A, delefilcon A, and etafilcon A with polyvinylpyrrolidone (PVP), daily disposable SCL material, using a modified pendulum-type friction tester. Sample SCLs were set on an acrylic plastic half-ball and placed into the polyethylene terephthalate hemisphere cup filled with 0.4 mL of test lubricants that included saline and 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% (wt/vol) HA (molecular weight, 850 kDa). The viscosities of saline and HA were measured using an Ubbelohde viscometer.Results:The CoF of the SCL under a low concentration (0.05%) of HA was the lowest and significantly lower than saline in narafilcon A and delefilcon A (P<0.05, Steel multiple comparison test). Under higher HA concentrations (0.3%, 0.4%, and 0.5%), the CoF was significantly higher than that of saline (P<0.01, Steel' multiple comparison test) in all three SCLs. There were no significant differences of CoF among three SCLs in saline and all concentrations of HA. The HA viscosities increased exponentially with the concentration (Y=1.2829e9.286X).Conclusion:The viscosity of a high concentration of HA may increase the friction of SCLs, which may have a deleterious effect on the ocular surface.

A moisturizing gel with high concentration of hyaluronic acid in niosomes for vaginal dryness and dyspareunia. Interim analysis of a clinical trial

Objective: To evaluate the safety and efficacy of Idracare® -a moisturizing vaginal gel with high concentration of hyaluronic acid in niosomes, prebiotics and Aloe vera- for the treatment of the symptoms associated with vulvovaginal atrophy.

Hyaluronic Acid Concentration in Female Vocal Folds With Reinke's Edema.

The aim of the present study was to investigate hyaluronic acid (HA) concentrations in vocal folds among patients with Reinke's edema. Prospective and experimental study. Single tertiary center. An HA binding protein isolated from bovine nasal cartilage was used to identify and isolate the HA from samples. Plates coated with biotin-conjugated binding protein and streptavidin-europium conjugate were sequentially incubated with 18 Reinke's edema samples and 11 female vocal fold cover samples from cadavers (the superficial layer of the lamina propria; control group). After the release of europium from streptavidin in enhancement solution, final fluorescence was measured in a fluorometer. The mean HA concentration in Reinke's edema vocal folds was significantly higher than that in the control vocal folds (9.2 × 103 vs 0.9 × 103µg/g). Vocal fold covers affected by Reinke's edema present a higher concentration of HA than do vocal fold covers with no edema.

Effect of a single-shot injection of a high-density hyaluronic acid gel in patients with symptomatic primary knee osteoarthritis: results of no-dolor study

Purpose: The main objective of this study (NO-DOLOR study) is to evaluate the evolution of pain in patients with primary knee osteoarthritis (OA), after a single injection of a high-density viscoelastic gel, which contains a high concentration of hyaluronic acid (HA) (Pronolis® HD mono 2.5%: 120 mg HA in 4.8 ml).

A Nano “Immune‐Guide” Recruiting Lymphocytes and Modulating the Ratio of Macrophages from Different Origins to Enhance Cancer Immunotherapy

AbstractArtificially modulating the type, density, and location of immune cells within the tumor microenvironment can suppress tumor growth and efficiently promote current immunotherapy. In this study, a magnetite nanoparticle‐based “immune‐guide” is developed by the functionalization of magnetite nanoparticles with hyaluronic acid (HA). HA, an extracellular matrix component, can target various CD44‐overexpressing tumors and mediate the adhesion and migration of multiple types of immune cells. Thus, HA‐functionalized magnetite nanoparticles (HA‐PDA@Fe3O4) can highly efficiently accumulate in breast cancer and penetrate deep into the tumor parenchyma. Consequently, high intratumoral concentration of HA, serving as a “guidepost,” can directly recruit lymphocytes and elicit more chemokine production through cascading amplification effects, turning the immune “cold” tumor into a “hot” one. More importantly, HA‐PDA@Fe3O4 can effectively remodel the diversity, origin, and activation of tumor‐associated macrophages by recruiting and activating infiltrating macrophages, while simultaneously reducing the M2‐maintained tissue‐resident macrophages. Thus, HA‐PDA@Fe3O4 synergistically improves T cell‐ and macrophage‐based immunotherapies as well as interferes with the formation of premetastatic niches in the lung. By redistributing the localization of HA in tumors by using magnetite nanoparticles, this study provides a unique strategy to modulate the tumor immune microenvironment and potentiate tumor immunotherapies by using biocompatible nanomaterials without any therapeutic drug.

Chemical and mechanical characterization of hyaluronic acid hydrogel cross-linked with polyethylen glycol and its use in dermatology.

Hydrogels based on hyaluronic acid are used to restore volume, hydration, and skin tone, as well as to correct scars, asymmetries or defects of the soft tissue. Hyaluronic acid is often chemically crosslinked with different crosslinking agents in order to improve its mechanical and biological properties. Here we focused on defining the chemical and mechanical characterization of a new hydrogel with specific characteristics: hyaluronic acid polyethylene glycol (PEG)-crosslinked with a high concentration of hyaluronic acid (28 mg/mL), manufactured by MatexLab Spa, via Carlo Urbani 2, ang Via Enrico Fermi, Brindisi, Italy. We made a quantitative and qualitative analysis of the content of sodium hyaluronate in the hydrogel after polymerization and sterilization processes and also evaluated histologically the bio integration of these hydrogels in the cutaneous soft tissues. The results suggest that hyaluronic acid hydrogel PEG-crosslinked have great bio integration, great chemical and mechanical properties, compared with other products available on the market, that are cross-linked with different cross-linking agents. The nontoxicity and nonimmunogenicity of PEG guarantee the lack of allergic and immunological reactions. The PEG-crosslinking technology guarantees a high duration time of the implanted hydrogel because of more resistant physiological degradation.

Hyaluronic Acid-Pluronic®F127-Laden Soft Contact Lenses for Corneal Epithelial Healing: In Vitro and In Vivo Studies.

Hyaluronic acid (HA) is widely used to treat various ocular diseases like dry eye syndrome, keratoconus, and other corneal epithelial injuries. The currently available eye drop solutions need frequent doses affecting the routine life style of patients. In this work, the silicone contact lens was designed to entrap HA and Pluronic®F127 to improve the wettability of the contact lens to treat various ocular diseases. The soaking method (HA-SM) was compared with the direct entrapment (DL-HA-PI) technique. The HA-Pluronic®F127-laden contact lenses (DL-HA-PI) showed acceptable optical transmittance with improved swelling (water content) properties. The in vitro release data showed high burst release with HA-SM contact lenses (12-36h), while DL-HA-PI contact lenses showed prolong release up to 96h. The in vivo release in the rabbit tear fluid showed high HA concentration (tear fluid) with DL-HA-PI contact lenses in comparison to the HA-SM contact lenses. The DL-HA-PI-3 batch with Pluronic®F127 showed more promising results in schirmer strip study in comparison to DL-HA-3 batch (without Pluronic®F127). The presence of Pluronic®F127 with HA showed high potential to improve hydration property of the contact lens. The corneal healing model showed reduction in the ocular inflammatory symptoms with DL-HA-PI-3 batch, thus demonstrating the potential of HA and Pluronic®F127 to be used in various ocular diseases.

Analysis of efficiency of application of media with hyaluronic acid in cryoprotocols

According to the World Health Organization, about 2 million new couples experience infertility annually, and their number is growing. An effective way to overcome infertility is assisted reproductive technology (ART). Cryopreservation will rationally solve the issue of preservation and further use of embryos: to delay pregnancy for some time considering womans desire and to prevent ovarian hyperstimulation syndrome. Embryo freezing allows to reduce the rate of repeated ovarian stimulation and perform preimplantation genetic diagnosis. Over the past decades, various cryotransfer options have been proposed to increase ART treatment efficacy, including the use of a culture medium with a high concentration of hyaluronic acid, but there are conflicting data on the use of such a medium in ART programs.&#x0D; Aim. Evaluation of thawed embryo transfers efficacy using the hyaluronic acid-containing culture medium. To achieve the goal, the following tasks were set: to evaluate clinical and medical history data of patients with tubal infertility in cryoprotocols, to analyze the previous cycle of in vitro fertilization and embryological stage, to evaluate the effectiveness of the culture medium with a high content of hyaluronic acid.&#x0D; Materials and methods. A detailed description of the patient sample, inclusion and exclusion criteria, embryological stage, embryo grading, devitrified embryo transfer technique. The article includes 3 tables which present the groups general clinical characteristics, the embryological stage, the rate of pregnancy, depending on the cultivation day.&#x0D; Results. The authors established that in patients with a history of pelvic surgery and sexually transmitted infections, it is advisable to use the culture medium with a high content of hyaluronic acid to transfer the thawed embryo. It was shown that pregnancy rate is 1.5 times higher when transferring devitrified embryos on the 5th day of development with the use of hyaluronic acid-containing culture medium.&#x0D; The conclusion about the pregnancy rate in obese patients is not indisputable, which requires further study. The authors also provide practical recommendations on the use of the culture medium with hyaluronic acid in cryoprotocols.&#x0D; Conclusion. The study allows to optimize the devitrified embryo transfer in patients with tubal infertility using a culture medium with a high content of hyaluronan. This work has undoubted scientific and practical significance.

Histological and Quantitative Appraisal of the Intradermal and Subcutaneous Distribution of the Hyaluronic Acid Injected into the Nasolabial Fold.

Histological analysis of hyaluronic acid (HA) applied in the nasolabial fold (NLF) studied gel distribution into the dermis and subcutaneous fat, correlating density of NLF tissues, with cohesivity, concentration and degradation of HA. Ten patients received two injection points on each NLF. They were intradermal near the nasal ala and subcutaneous near the oral commissure. Injection points received 0.1ml of 24mg/ml HA cross-linked by BDDE 2.0ppm through a bolus technique injection without retrograde backflow. Biopsies were taken 72h and 9months after application to histological analysis. Dermis density fragmented the gel into small nodules, spreading it into the reticular dermis. Seventy-two hours after application, average diameter of the small nodules was 0.30mm and at month nine 0.05mm. Softness of the subcutaneous fat and high concentration of HA created a single and compact nodule. Seventy-two hours after application, average of nodule diameters was 1.05mm and at month nine 0.49mm. HA biodegradation occurred on the external surface of the gel. The single nodule offered small contact surface to enzymes, slowing gel degradation. The sum average of the diameters of the small nodules offered a large contact surface to enzymes, accelerating gel degradation. Permanence of the HA into the tissues depended on the relationship between the gel distribution and its degradation. Due to the small contact surface of the single nodule to enzymes, permanence of the HA into the subcutaneous fat was more extended than into the dermis. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Sensitivity of Hyaluronic Acid Fillers to Hyaluronidase: An in vitro Analysis

Objective: The purpose of this study was to provide qualitative information on the in vitro dissolution of hyaluronic acid (HA) fillers upon exposure to hyaluronidase and to determine whether in vitro sensitivity of fillers relates to clinical findings in patients treated with hyaluronidase to manage complications of HA filler placement. Methods: The authors undertook an in vitro study to evaluate how 6 types of HA fillers respond to hyaluronidase exposure. The findings were compared to outcomes in 3 clinical cases in which hyaluronidase was given to manage adverse outcomes of HA injection. Results: The fillers responded differently to the same dose of hyaluronidase. Fillers with a higher concentration of HA or a greater degree of crosslinking generally were more resistant to enzymatic dissolution. Clinical findings were consistent with in vitro results. Conclusion: The sensitivities of HA fillers to hyaluronidase in vitro were consistent with clinical findings.

Umbilical cord-derived Wharton\u2019s jelly for regenerative medicine applications

BackgroundThe last decade has seen an explosion in the interest in using biologics for regenerative medicine applications, including umbilical cord-derived Wharton’s Jelly. There is insufficient literature assessing the amount of growth factors, cytokines, hyaluronic acid, and extracellular vesicles including exosomes in these products. The present study reports the development of a novel Wharton’s jelly formulation and evaluates the presence of growth factors, cytokines, hyaluronic acid, and extracellular vesicles including exosomes.MethodsHuman umbilical cords were obtained from consenting caesarian section donors. The Wharton’s jelly was then isolated from the procured umbilical cord and formulated into an injectable form. Randomly selected samples from different batches were analyzed for sterility testing and to quantify the presence of growth factors, cytokines, hyaluronic acid, and extracellular vesicles.ResultsAll samples passed the sterility test. Growth factors including IGFBP 1, 2, 3, 4, and 6, TGF-α, and PDGF-AA were detected. Several immunomodulatory cytokines, such as RANTES, IL-6R, and IL-16, were also detected. Pro-inflammatory cytokines MCSFR, MIP-1a; anti-inflammatory cytokines TNF-RI, TNF-RII, and IL-1RA; and homeostatic cytokines TIMP-1 and TIMP-2 were observed. Cytokines associated with wound healing, ICAM-1, G-CSF, GDF-15, and regenerative properties, GH, were also expressed. High concentrations of hyaluronic acid were observed. Particles in the extracellular vesicle size range were also detected and were enclosed by the membrane, indicative of true extracellular vesicles.ConclusionThere are numerous growth factors, cytokines, hyaluronic acid, and extracellular vesicles present in the Wharton’s jelly formulation analyzed. The amount of these factors in Wharton’s jelly is higher compared with other biologics and may play a role in reducing inflammation and pain and augment healing of musculoskeletal injuries.

The interaction between hyaluronidase and hyaluronic acid gel fillers - a review of the literature and comparative analysis

Hyaluronic acid (HA) is the most common component of aesthetic fillers. Many formulations exist, each exhibiting properties that are manifestations of individual molecular modifications. The enzyme hyaluronidase degrades hyaluronic acid and can therefore be injected into soft tissue to reduce suboptimally placed HA fillers or to reverse local ischemic complications. The clinically available varieties of hyaluronidase may be derived from crude animal extracts or genetically engineered from recombinant human DNA. Different HA fillers are not uniformly dissolved by a single source hyaluronidase, and hyaluronidase from different sources may have varying efficacy in the degradation of HA. Previous studies of subsets of HA fillers and hyaluronidases have provided limited and often conflicting data regarding these differences, and a more comprehensive scientific study is needed. In this review, the authors describe commonly available formulations of HA and hyaluronidase and review all studies of HA-hyaluronidase interaction available via a PubMed and Google Scholar search from 2005 to present, exploring trends in the data. Factors determined to confer increased resistance to degradation included higher concentration of HA, higher crosslinking density, and status as monophasic versus biphasic. Fillers of the Juvéderm family were generally found to be more resistant to degradation than members of the Restylane family. Results are less consistent for Belotero Balance. No variety of hyaluronidase was consistently superior at dissolving any variety of HA filler. More research is needed to clarify these clinically relevant relationships.

In situ observation of lubricant film formation in THR considering real conformity: The effect of model synovial fluid composition

Abstract The present paper explores the effect of synovial fluid composition on lubricant film formation in hip replacements. The measurements were realized utilizing pendulum hip joint simulator, while the film thickness was evaluated using optical interferometry. Contact couples consisted of metal and ceramic femoral heads articulating with glass acetabular cups. As the test lubricants, various model fluids were employed. Initially, static tests, aimed on the effect of material and load on adsorption, were conducted. It was found that adsorbed film thickness increases independently of the head material. Consequently, swinging flexion-extension experiments were realized, revealing that the film formation is substantially affected by composition of model fluid. The thickest film was observed when higher concentration of hyaluronic acid and phospholipids was applied.

Protein Expression Level of Skin Wrinkle-Related Factors in Hairless Mice Fed Hyaluronic Acid.

The aim of this study was to evaluate the wrinkle improving effect of hyaluronic acid intakes. Wrinkles were induced by exposing the skin of hairless mice to ultraviolet B (UVB) irradiation for 14 weeks. Hyaluronic acid was administered to the mice for 14 weeks including 4 weeks before experiments. Skin tissue was assayed by enzyme-linked immunosorbent assay to determine protein expression of wrinkle-related markers. The group supplemented with high concentrations of hyaluronic acid appeared significantly better than control group for collagen, matrix metalloproteinase 1, interleukin (IL)-1β, and IL-6 assay. Transforming growth factor-β1 (TGF-β1) and hyaluronic acid synthase 2 (HAS-2) were not shown to be significantly different. In conclusion, hyaluronic acid administration regulated expression levels of proteins associated with skin integrity, and improved the wrinkle level in skin subjected to UVB irradiation.

Mixtures of hyaluronic acid and liposomes for drug delivery: Phase behavior, microstructure and mobility of liposomes

Hyaluronic acid liposomal gels have previously demonstrated in vivo their great potential for drug delivery. Elucidating their phase behavior and structure would provide a better understanding of their use properties. This work evaluates the microstructure and the phase behavior of mixtures of hyaluronic acid (HA) and liposomes and their impact on the vesicle mobility. HA concentration and surface properties of liposomes (positively or negatively charged, neutral, with a polyethylene glycol corona) are varied while the liposome concentration remains constant. Below the entanglement concentration of HA (0.4%), the mixtures exhibit a depletion phase separation except for positively charged liposomes that interact with anionic HA through attractive electrostatic interactions. At high HA concentration, no macroscopic phase separation is observed, except a slight syneresis with cationic liposomes. The microstructure shows aggregates of liposomes homogeneously distributed into a HA network except for PEGylated liposomes, which seem to form bicontinuous interpenetrating networks. The diffusion of liposomes is controlled by HA concentration and their surface properties. Finally, PEGylated liposomes display the highest mobility at high HA concentration (2.28%) both macro- and microscopically. The microstructure of HA-liposomes mixtures and the diffusion of liposomes are key parameters that must be taken into account for drug delivery.

Synovial fluid pretreatment with hyaluronidase facilitates isolation of CD44+ extracellular vesicles

Extracellular vesicles (EVs) in synovial fluid (SF) are gaining increased recognition as important factors in joint homeostasis, joint regeneration, and as biomarkers of joint disease. A limited number of studies have investigated EVs in SF samples of patients with joint disease, but knowledge on the role of EVs in healthy joints is lacking. In addition, no standardized protocol is available for isolation of EVs from SF. Based on the high viscosity of SF caused by high concentrations of hyaluronic acid (HA) – a prominent extracellular matrix component – it was hypothesized that EV recovery could be optimized by pretreatment with hyaluronidase (HYase). Therefore, the efficiency of EV isolation from healthy equine SF samples was tested by performing sequential ultracentrifugation steps (10,000g, 100,000g and 200,000g) in the presence or absence of HYase. Quantitative EV analysis using high-resolution flow cytometry showed an efficient recovery of EVs after 100,000g ultracentrifugation, with an increased yield of CD44+ EVs when SF samples were pretreated with HYase. Morphological analysis of SF-derived EVs with cryo-transmission-electron microscopy did not indicate damage by high-speed ultracentrifugation and revealed that most EVs are spherical with a diameter of 20–200 nm. Further protein characterization by Western blotting revealed that healthy SF-derived EVs contain CD9, Annexin-1, and CD90/Thy1.1. Taken together, these data suggest that EV isolation protocols for body fluids that contain relatively high amounts of HA, such as SF, could benefit from treatment of the fluid with HYase prior to ultracentrifugation. This method facilitates recovery and detection of CD44+ EVs within the HA-rich extracellular matrix. Furthermore, based on the findings presented here, it is recommended to sediment SF-derived EVs with at least 100,000g for optimal EV recovery.