High Molecular Weight Hyaluronic Acid Research Articles

Efficacy of single high-molecular-weight versus triple low-molecular-weight hyaluronic acid intra-articular injection among knee osteoarthritis patients

BackgroundTo compare intra-articular (IA) knee injections of a cross-linked high-molecular-weight hyaluronic acid (HMW-HA) with a linear low-molecular weight HA (LMW-HA) in terms of pain and functional improvement among knee osteoarthritis (OA) patients.MethodsIn this single-blinded RCT, the patients were randomly divided into two groups for HA injections. The first group received an HMW-HA (Arthromac) injection, while the other received three weekly LMW-HA (Hyalgan) injections. Pain and function were assessed using the outcome measures including WOMAC, Lequesne and VAS indices, once prior to injection, as well as 2 and 6 months after injections.ResultsA total of 90 patients were included. There was no significant difference in baseline characteristics including age and sex between the two groups. Our analysis showed that total WOMAC, Lequesne and VAS mean scores remarkably improved at both follow-up time-points compared to the baseline measurements (p < 0.001). There was no significant superiority between the two therapeutic protocols according to our outcome measures at any time-point of follow-up. The only except was about the improvement in WOMAC stiffness subscale that was significantly higher in LMW-HA group compared to HMW-HA (p = 0.021). Moreover, no significant difference was observed in minor complications and injection-induced pain scores between the two groups.ConclusionThis study proved that a single HMW-HA injection is as effective as multiple injections of LMW-HA counterparts in periods of 2 and 6 months follow-up.This study protocol was registered in Iranian database of RCTs (IRCT; www.irct.ir) with the trial registration number IRCT20130523013442N24 and registration date 2018-07-13.

Abstract 3961: Influence of hyaluronic acid in tumor microenvironment on glioblastoma (GBM) invasive behavior

Abstract Glioblastoma invasion is mediated by distinct interactions between tumor cells and the extracellular matrix. Engineered biomaterial platforms allow for systemic examination of the influence of the microenvironment HA content on GBM cell activity. In this study, high molecular weight hyaluronic acid (700 kDa) was photopolymerized within three-dimensional (3D) polyethylene-glycol (PEG) hydrogels and patient-derived, primary GBM cell migration in the HA-hydrogels was investigated. Hydrogel polymerization conditions were tuned to achieve orthogonal control of HA content in a series of hydrogels (0.1 - 0.75 wt% HA) with conserved poroelastic properties (i.e. storage moduli and diffusivity). GBM cell migration was strongly influenced by microenvironment HA content. Knockdown of HA-dependent cell surface receptors (CD44 and RHAMM) modulated GBM cell activity. Our results demonstrate that alterations in microenvironment HA content and inhibition of HA-dependent signaling produced distinct molecular and phenotypic differences in GBM migratory behavior. These results demonstrate the differential effect of tumor microenvironment HA content on the invasive phenotype of GBM in a physiologically relevant 3D culture environment. Citation Format: Itay Solomon, Alireza Sohrabi, Stephanie K. Seidlits. Influence of hyaluronic acid in tumor microenvironment on glioblastoma (GBM) invasive behavior [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3961.

Crossing the hurdles of translation—a robust methodology for synthesis, characterization and GMP production of cross‐linked high molecular weight hyaluronic acid particles (cHA)

AbstractHyaluronic acid (HA) is one of the most widely used extracellular matrix substrate in tissue engineering, drug delivery, and other clinical applications, due to its unique physiochemical properties and ubiquitous biological presence. In the past decade, there has been a surge in research paradigms involving HA products to evaluate their commercial feasibility. Numerous papers and reviews have reported procedures for chemical modifications and cross‐linking of HA, but the intricacies of their scale‐up in the production processes are often not discussed. Protected by confidentiality agreements with industry partners, information on these procedures is exclusive and not accessible within an academic setting. Establishing translatable synthetic protocols of HA would address this significant gap in the field and facilitate their use in other applications. The current method details a reproducible and robust method for producing particles that are composed of high molecular weight hyaluronic acid (cHA) and cross‐linked via a 4‐arm polyethylene glycol amine linker using 4‐(4,6‐dimethoxy‐1,3,5‐triazin‐2‐yl)‐4‐methyl‐morpholinium chloride chemistry. A critical analysis of previously reported procedures for their advantages and limitations (reaction parameters, molar equivalents, and reagents used for cross‐linking), forms the basis for this procedure and its subsequent adaptation to good manufacturing practices requirements. As a component of a Class III medical device, the reported cHA is in the form of non‐sized particles.

Dual Cross-linked HHA Hydrogel Supplies and Regulates MΦ2 for Synergistic Improvement of Immunocompromise and Impaired Angiogenesis to Enhance Diabetic Chronic Wound Healing.

Immunocompromise and impaired angiogenesis of diabetes lead to chronic inflammation when wounds occur, which is the primary reason for the long-term incurable nature of diabetic chronic wounds. Herein, a high-molecular-weight hyaluronic acid (HHA) hydrogel is developed to supply and regulate M2 phenotype macrophages (MΦ2) for synergistic improvement of immunocompromise and impaired angiogenesis. MΦ2 are seeded on the Cu-HHA/PVA hydrogels prepared by Cu2+ cross-linking of low degree and physical cross-linking (one freeze-thaw cycle and unique lyophilization) to form Cu-HHA/PVA@MΦ2 hydrogels. The Cu-HHA/PVA@MΦ2 hydrogel can directly supply the MΦ2 in the wound site, maintain the consistent phenotype of loaded MΦ2, and transform the M1 phenotype macrophages (MΦ1) in the wound bed to MΦ2 by HHA. Furthermore, Cu2+ could be released from the hydrogels to further stimulate angiogenesis, thus accelerating the wound-healing phase transition from inflammation to proliferation and remodeling. The average wound area after the 0.5Cu-HHA/PVA@MΦ2 (ionic cross-linking degree 0.5%) treatment was much smaller than that of other diabetic groups at day 12 and close to that of the wild nondiabetic control group. Therefore, this facile hydrogel strategy with multiple modulation mechanisms of immunocompromise and angiogenesis may act as a safe and effective treatment strategy for a diabetic chronic wound.

Hyaluronic Acid-Based Bioink Composition Enabling 3D Bioprinting and Improving Quality of Deposited Cartilaginous Extracellular Matrix.

In 3D bioprinting, bioinks with high concentrations of polymeric materials are frequently used to enable fabrication of 3D cell-hydrogel constructs with sufficient stability. However, this is often associated with restricted cell bioactivity and an inhomogeneous distribution of newly produced extracellular matrix (ECM). Therefore, this study investigates bioink compositions based on hyaluronic acid (HA), an attractive material for cartilage regeneration, which allow for reduction of polymer content. Thiolated HA and allyl-modified poly(glycidol) in varying concentrations are UV-crosslinked. To adapt bioinks to poly(ε-caprolactone) (PCL)-supported 3D bioprinting, the gels are further supplemented with 1wt% unmodified high molecular weight HA (hmHA) and chondrogenic differentiation of incorporated human mesenchymal stromal cells is assessed. Strikingly, addition of hmHA to gels with a low polymer content (3wt%) results in distinct increase of construct quality with a homogeneous ECM distribution throughout the constructs, independent of the printing process. Improved ECM distribution in those constructs is associated with increased construct stiffness after chondrogenic differentiation, as compared to higher concentrated constructs (10wt%), which only show pericellular matrix deposition. The study contributes to effective bioink development, demonstrating dual function of a supplement enabling PCL-supported bioprinting and at the same time improving biological properties of the resulting constructs.

Inhibition of HAS2 and hyaluronic acid production by 1,25-Dihydroxyvitamin D3 in breast cancer.

1,25-Dihydroxyvitamin D3 (1,25D3) induces growth arrest and apoptosis in breast cancer cells in vivo and in vitro, however the exact mechanisms are unclear. Although the vitamin D receptor (VDR), a ligand dependent transcription factor, is required for growth regulation by vitamin D, the specific target genes that trigger these effects are unknown. Genomic profiling of murine mammary tumor cells with differential VDR expression identified 35 transcripts that were altered by the 1,25D3-VDR complex including Hyaluronan Synthase-2 (Has2). Here we confirmed that 1,25D3 reduces both HAS2 gene expression and hyaluronic acid (HA) synthesis in multiple models of breast cancer. Furthermore, we show that the growth inhibitory effects of 1,25D3 are partially reversed in the presence of high molecular weight HA. HAS2 expression and HA production are elevated in immortalized human mammary epithelial cells induced to undergo epithelial-mesenchymal transition (EMT) through stable expression of TGFβ, SNAIL or TWIST and in those expressing oncogenic H-RASV12, indicating that deregulation of HA production may be an early and frequent event in breast tumorigenesis. 1,25D3 also reduces HA secretion and acts additively with an HA synthesis inhibitor to slow growth of cells expressing TGFβ, SNAIL and TWIST. Analysis of mammary gland and tumors from Vdr knockout mice suggest that loss of VDR is associated with enhanced HAS2 expression and HA production in vivo. These data define a novel role for 1,25D3 and the VDR in control of HA synthesis in epithelial tissues that likely contributes to its anti-cancer actions.

Corrigendum to "Novel Hybrid Gels Made of High and Low Molecular Weight Hyaluronic Acid Induce Proliferation and Reduce Inflammation in an Osteoarthritis In Vitro Model Based on Human Synoviocytes and Chondrocytes".

[This corrects the article DOI: 10.1155/2019/4328219.].

Why Chain Length of Hyaluronan in Eye Drops Matters.

The chain length of hyaluronan (HA) determines its physical as well as its physiological properties. Results of clinical research on HA eye drops are not comparable without this parameter. In this article methods for the assessment of the average molecular weight of HA in eye drops and a terminology for molecular weight ranges are proposed. The classification of HA eye drops according to their zero shear viscosity and viscosity at 1000 s−1 shear rate is presented. Based on the gradient of mucin MUC5AC concentration within the mucoaqueous layer of the tear film a hypothesis on the consequences of this gradient on the rheological properties of the tear film is provided. The mucoadhesive properties of HA and their dependence on chain length are explained. The ability of HA to bind to receptors on the ocular epithelial cells, and in particular the potential consequences of the interaction between HA and the receptor HARE, responsible for HA endocytosis by corneal epithelial cells is discussed. The physiological function of HA in the framework of ocular surface homeostasis and wound healing are outlined, and the influence of the chain length of HA on the clinical performance of HA eye drops is illustrated. The use of very high molecular weight HA (hylan A) eye drops as drug vehicle for the next generation of ophthalmic drugs with minimized side effects is proposed and its advantages elucidated. Consequences of the diagnosis and treatment of ocular surface disease are discussed.

The Role of an IL-10/Hyaluronan Axis in Dermal Wound Healing.

Scar formation is the typical endpoint of postnatal dermal wound healing, which affects more than 100 million individuals annually. Not only do scars cause a functional burden by reducing the biomechanical strength of skin at the site of injury, but they also significantly increase healthcare costs and impose psychosocial challenges. Though the mechanisms that dictate how dermal wounds heal are still not completely understood, they are regulated by extracellular matrix (ECM) remodeling, neovascularization, and inflammatory responses. The cytokine interleukin (IL)-10 has emerged as a key mediator of the pro- to anti-inflammatory transition that counters collagen deposition in scarring. In parallel, the high molecular weight (HMW) glycosaminoglycan hyaluronan (HA) is present in the ECM and acts in concert with IL-10 to block pro-inflammatory signals and attenuate fibrotic responses. Notably, high concentrations of both IL-10 and HMW HA are produced in early gestational fetal skin, which heals scarlessly. Since fibroblasts are responsible for collagen deposition, it is critical to determine how the concerted actions of IL-10 and HA drive their function to potentially control fibrogenesis. Beyond their independent actions, an auto-regulatory IL-10/HA axis may exist to modulate the magnitude of CD4+ effector T lymphocyte activation and enhance T regulatory cell function in order to reduce scarring. This review underscores the pathophysiological impact of the IL-10/HA axis as a multifaceted molecular mechanism to direct primary cell responders and regulators toward either regenerative dermal tissue repair or scarring.

Hyaluronan promotes the regeneration of vascular smooth muscle with potent contractile function in rapidly biodegradable vascular grafts

The regeneration of smooth muscle with physiological functions has been a key challenge in vascular tissue engineering. Hyaluronan (HA), as a major component of the extracellular matrix, plays a vital role in regulating tissue injury and repair. In this study, a biomimetic vascular graft was prepared by co-electrospinning of synthetic degradable polymers and native ECM components including collagen type-I as well as low and high molecular weight HA (LMW HA and HMW HA). Upon implantation in the rat abdominal aorta, the grafts exhibited sustained HA release that effectively enhanced the regeneration of vascular smooth muscle. Besides, LMW HA loaded vascular grafts demonstrated rapid endothelialization compared to the other groups. More importantly, HA-loaded poly(L-lactide-co-caprolactone) grafts demonstrated an optimal vascular media layer accompanied by well-organized elastin fibers after long-term implantation (6 months), and they maintained potent physiological function up to 1/3 that of the native artery. In contrast, inadequate smooth muscle regeneration was observed in poly(ε-caprolactone) grafts due to slow degradation restricting the regeneration. The mechanism was further investigated and explained by the HA-induced migration of smooth muscle cell (SMC) via CD44-mediated signaling. Besides, low molecular weight HA can promote the migration of vascular progenitor cells that further differentiate into SMCs. These results highlight the importance of HA in the regeneration of functional vascular smooth muscle, and provide a new insight into the fabrication of tissue engineering vascular grafts (TEVGs) via combining rapidly degradable polymers and bioactive ECM components that hold great translational potential.

Mechanisms Mediating High-Molecular-Weight Hyaluronan-Induced Antihyperalgesia.

We evaluated the mechanism by which high-molecular-weight hyaluronan (HMWH) attenuates nociceptor sensitization, in the setting of inflammation. HMWH attenuated mechanical hyperalgesia induced by the inflammatory mediator prostaglandin E2 (PGE2) in male and female rats. Intrathecal administration of an oligodeoxynucleotide antisense (AS-ODN) to mRNA for cluster of differentiation 44 (CD44), the cognate hyaluronan receptor, and intradermal administration of A5G27, a CD44 receptor antagonist, both attenuated antihyperalgesia induced by HMWH. In male rats, HMWH also signals via Toll-like receptor 4 (TLR4), and AS-ODN for TLR4 mRNA administered intrathecally, attenuated HMWH-induced antihyperalgesia. Since HMWH signaling is dependent on CD44 clustering in lipid rafts, we pretreated animals with methyl-β-cyclodextrin (MβCD), which disrupts lipid rafts. MβCD markedly attenuated HMWH-induced antihyperalgesia. Inhibitors for components of intracellular signaling pathways activated by CD44, including phospholipase C and phosphoinositide 3-kinase (PI3K), also attenuated HMWH-induced antihyperalgesia. Furthermore, in vitro application of HMWH attenuated PGE2-induced sensitization of tetrodotoxin-resistant sodium current, in small-diameter dorsal root ganglion neurons, an effect that was attenuated by a PI3K inhibitor. Our results indicate a central role of CD44 signaling in HMWH-induced antihyperalgesia and suggest novel therapeutic targets, downstream of CD44, for the treatment of pain generated by nociceptor sensitization.SIGNIFICANCE STATEMENT High-molecular-weight-hyaluronan (HMWH) is used to treat osteoarthritis and other pain syndromes. In this study we demonstrate that attenuation of inflammatory hyperalgesia by HMWH is mediated by its action at cluster of differentiation 44 (CD44) and activation of its downstream signaling pathways, including RhoGTPases (RhoA and Rac1), phospholipases (phospholipases Cε and Cγ1), and phosphoinositide 3-kinase, in nociceptors. These findings contribute to our understanding of the antihyperalgesic effect of HMWH and support the hypothesis that CD44 and its downstream signaling pathways represent novel therapeutic targets for the treatment of inflammatory pain.

Addition of High Molecular Weight Hyaluronic Acid to Fibroblast-Like Stromal Cells Modulates Endogenous Hyaluronic Acid Metabolism and Enhances Proteolytic Processing and Secretion of Versican.

We have examined the effect of exogenous linear chain high molecular weight hyaluronic acid (HMW HA) on endogenously synthesized hyaluronic acid (HA) and associated binding proteins in primary cultures of fibroblast-like stromal cells that were obtained by collagenase digestion of the murine peripatellar fat pad. The cultures were expanded in DMEM that was supplemented with fetal bovine serum and basic fibroblast growth factor (bFGF) then exposed to macrophage-colony-stimulating factor (MCSF) to induce macrophage properties, before activation of inflammatory pathways using E. coli lipopolysaccharide (LPS). Under all culture conditions, a significant amount of endogenously synthesized HA localized in LAMP1-positive lysosomal vesicles. However, this intracellular pool was depleted after the addition of exogenous HMW HA and was accompanied by enhanced proteolytic processing and secretion of de novo synthesized versican, much of which was associated with endosomal compartments. No changes were detected in synthesis, secretion, or proteolytic processing of aggrecan or lubricin (PRG4). The addition of HMW HA also modulated a range of LPS-affected genes in the TLR signaling and phagocytosis pathways, as well as endogenous HA metabolism genes, such as Has1, Hyal1, Hyal2, and Tmem2. However, there was no evidence for association of endogenous or exogenous HMW HA with cell surface CD44, TLR2 or TLR4 protein, suggesting that its physiochemical effects on pericelluar pH and/or ionic strength might be the primary modulators of signal transduction and vesicular trafficking by this cell type. We discuss the implications of these findings in terms of a potential in vivo effect of therapeutically applied HMW HA on the modification of osteoarthritis-related joint pathologies, such as pro-inflammatory and degradative responses of multipotent mesenchymal cells residing in the synovial membrane, the underlying adipose tissue, and the articular cartilage surface.

A novel approach for knee osteoarthritis using high molecular weight hyaluronic acid conjugated to plasma fibrinogen – interim findings of a double-blind clinical study

ObjectiveOsteoarthritis (OA) is a widespread degenerative joint disease leading to progressive loss of function and pain. Available treatments do not provide long-term relief or improvement. This study aimed to assess the safety and efficacy of a novel intra articular supplement, made of high molecular-weight hyaluronic acid (HA) uniquely conjugated to either purified (RegenoGel) or autologous plasma-derived fibrinogen (RegenoGel-OSP), as a long-term treatment for knee OA. MethodsSixty-seven consecutive participants (mean age 67.26 ± 7 years) with symptomatic OA were randomly assigned to receive intraarticular injections of either RegenoGel, RegenoGel-OSP or saline solution (placebo). The active treatment groups received a second, repeat injection of the corresponding treatment at the 3-month evaluation, at which time, the placebo group was divided into two subgroups, one receiving RegenoGel and the other receiving RegenoGel-OSP. The OA symptoms were assessed by VAS, WOMAC, and IKDC questionnaires at baseline and at 1, 3, 4, and 6 months following the first injection. OA-related quality of life was evaluated by the SF-12 survey. ResultsOur preliminary data suggests that both fibrin-HA formulations have positive effects on OA symptoms for all assessed parameters with the most prominent trend for reduction in OA-associated pain. Pooled data analysis of RegenoGel and RegenoGel-OSP shows significantly improved VAS scores compared to placebo at three months after the first injection, and sustained for another three months after the second injection. Both RegenoGel, RegenoGel-OSP had an excellent safety profile. ConclusionsInterim analysis results indicate that RegenoGel and RegenoGel-OSP are safe and are potentially effective for at least six months in alleviating pain and symptoms of knee OA.

Hyaluronan and halogen-induced airway hyperresponsiveness and lung injury.

Chlorine (Cl2 ) and bromine (Br2 ) are produced in large quantities throughout the world and used in the industry and the sanitation of water. These halogens can pose a significant threat to public health when released into the atmosphere during transportation and industrial accidents, or as acts of terrorism. In this review, we discuss the evidence showing that the activity of Cl2 and Br2 , and of products formed by their interaction with biomolecules, fragment high-molecular-weight hyaluronan (HMW-HA), a key component of the interstitial space and present in epithelial cells, to form proinflammatory, low-molecular-weight hyaluronan fragments that increase intracellular calcium (Ca2+ ) and activate RAS homolog family member A (RhoA) in airway smooth muscle and epithelial and microvascular cells. These changes result in airway hyperresponsiveness (AHR) to methacholine and increase epithelial and microvascular permeability. The increase in intracellular Ca2+ is the result of the activation of the calcium-sensing receptor by Cl2 , Br2 , and their by-products. Posthalogen administration of a commercially available form of HMW-HA to mice and to airway cells in vitro reverses the increase of Ca2+ and the activation of RhoA, and restores AHR to near-normal levels of airway function. These data have established the potential of HMW-HA to be a countermeasure against Cl2 and Br2 toxicity.

High-molecular weight hyaluronan attenuates tubulointerstitial scarring in kidney injury.

Renal fibrosis features exaggerated inflammation, extracellular matrix (ECM) deposition, and peritubular capillary loss. We previously showed that IL-10 stimulates high-molecular weight hyaluronan (HMW-HA) expression by fibroblasts, and we hypothesize that HMW-HA attenuates renal fibrosis by reducing inflammation and ECM remodeling. We studied the effects of IL-10 overexpression on HA production and scarring in mouse models of unilateral ureteral obstruction (UUO) and ischemia/reperfusion (I/R) to investigate whether IL-10 antifibrotic effects are HA dependent. C57BL/6J mice were fed with the HA synthesis inhibitor, 4-methylumbelliferone (4-MU), before UUO. We observed that in vivo injury increased intratubular spaces, ECM deposition, and HA expression at day 7 and onward. IL-10 overexpression reduced renal fibrosis in both models, promoted HMW-HA synthesis and stability in UUO, and regulated cell proliferation in I/R. 4-MU inhibited IL-10-driven antifibrotic effects, indicating that HMW-HA is necessary for cytokine-mediated reduction of fibrosis. We also found that IL-10 induces in vitro HMW-HA production by renal fibroblasts via STAT3-dependent upregulation of HA synthase 2. We propose that IL-10-induced HMW-HA synthesis plays cytoprotective and antifibrotic roles in kidney injury, thereby revealing an effective strategy to attenuate renal fibrosis in obstructive and ischemic pathologies.

Hyaluronic acid induction on breast cancer stem cells unfolds subtype specific variations in stemness and epithelial-to-mesenchymal transition

The reoccurrence of breast cancer is a major concern due to presence of cancer stem cells (CSCs). Considering the key role of hyaluronic acid (HA) in modulating the inflammation and cellular migration in cancer, the response of high molecular weight (HMW) and low molecular weight (LMW) HA towards various subtypes of breast cancer and breast cancer stem cells remain elusive. The aim of this study is to determine the effect of exogenous HMW-HA and LMW-HA on stemness of CSCs and epithelial-to-mesenchymal transition which may help in designing HA based therapeutic strategies. LMW-HA induces EMT in MCF-7 more prominently as compared to MDA-MB-231. However, HMW-HA did not show significant changes in the expression of EMT genes. Surprisingly, both HMW-HA and LMW-HA have shown to decrease the expression of EpCAM in MCF-7 cells and decrease the expression of CD44 in MDAMB-231 cells. HA has maintained the native stem cells phenotype of bCSCs isolated from MCF-7 only. The bCSCs isolated form MDAMB-231 showed a decrease in CD44. Luminal subtype has shown to follow Wnt/β-catenin whereas in the basal subtype localization of CD44 from surface to cytosol was observed in response to HA. Our study has demonstrated that bCSCs in luminal and basal cells follow differential intracellular signaling mechanisms in response to HA. This study could significantly influence the therapeutics involving HA in breast cancer.

Improvement of mechanical properties of orodispersible hyaluronic acid film by carboxymethyl cellulose addition.

Orodispersible films (ODF) were prepared with mixtures of hyaluronic acid (HA) and carboxymethyl cellulose (CMC), and the effect of CMC addition on the disintegration and mechanical properties of the composite films were examined. Low molecular weight HA (10kDa) appeared more acceptable for ODF than high molecular weight HA (800kDa) because of its rapid disintegration in the oral cavity. The composite films appeared similar to pullulan film with excellent transparency and surface smoothness. The disintegration time as well as mechanical properties of the films such as tensile strength and elongation at break were increased by the addition of CMC. Overall, the CMC addition, up to 35%, improved the mechanical properties of low molecular weight HA film within a proper range of disintegration time for ODF.

Dissolving microneedle with high molecular weight hyaluronic acid to improve skin wrinkles, dermal density and elasticity.

Dissolving microneedle patches have been extensively studied in the field of cosmetics comparison with topical cosmetics focusing on the delivery of active ingredients. Nevertheless, the skin improvement effect of hyaluronic acid, which is mainly used as a backbone material for dissolving microneedle, was not analyzed. In this study, adenosine encapsulated high and low molecular weight hyaluronic acid dissolving microneedle patch (Ad-HMN and Ad-LMN) were evaluated with respect to skin wrinkling, dermal density, elasticity, and safety in a clinical test on the crow's feet area. Clinical efficacy and safety tests were performed for 12weeks on twenty three female subjects with wrinkles around their eyes. The Ad-HMN and Ad-LMN patch were applied once every 3days, in the evening, for 8weeks to the designated crow's feet area. Skin wrinkling, dermal density, and elasticity were measured by using PRIMOS® premium, Dermascan® C, Cutometer® MPA580, and Corneometer® CM 825, respectively. Both Ad-HMN and Ad-LMN groups showed statistically significant efficacy for almost all parameters. The Ad-HMN patch had better effect on the mean depth of biggest wrinkles, maximum depth of biggest wrinkles, dermal density, and skin elasticity than the Ad-LMN patch. No adverse effects were observed in either group during the test period. In the clinical efficacy test of four skin-improvement parameters, the Ad-HMN patch showed the better effect than the Ad-LMN patch with the similar adenosine dose.

Hyaluronic acid binding to CD44S is indiscriminate of molecular weight

The ubiquitous presence of hyaluronic acid (HA) in the extracellular matrix (ECM) of both healthy and diseased tissues underscores its importance in human physiology. Previous studies suggest that HA can be used as a probe to qualitatively monitor cell surface levels of CD44 and other important HA receptors; however, these studies use mixtures of HA at various molecular weights. Using fluorescently labeled HA, we evaluated the apparent differences of low (25 kilodalton) and high (700 kilodalton) molecular weight HA interacting with breast cancer cell lines of varying levels of CD44. Our results confirm that CD44 expression and the apparent level of HA interaction correlates with molecular weight. Importantly, we show that HA only binds a small fraction of the major CD44 isoform, CD44S, on cell surfaces and that CD44S interactions account for <50% of the total HA bound to cell surfaces. Although increased fluorescence level correlates with higher molecular weight of HA, this appears to be an artifact of chain length and not a result of multivalent binding between HA and CD44S. Accordingly, we verify that HA binding characteristics of cell surfaces is similar to previous artificial membrane models which proposed that HA anchors to CD44S and forms a non-binding corona of HA that extends beyond the surface.

The Effects of High Molecular Weight Hyaluronic Acid Eye Drop Application in Environmental Dry Eye Stress Model Mice.

Hyaluronic acid (HA) ophthalmic solution is widely used in dry eye treatment worldwide. However, there are no reports comparing the dry eye treatment effects of high molecular weight HA with low molecular weight HA. Sixty eight-week-old C57BL/6 mice were assigned to the following 6 groups and exposed to environmental dry eye stress (EDES) that mimics office work environment: (1) 0.1% low molecular weight HA (LMWHA) eye drops, (2) 0.3% LMWHA eye drops, (3) 3% diquafosol sodium (DQ) eye drops, (4) 0.15% high molecular weight HA (HMWHA) eye drops, (5) no treatment with exposure to EDES (EDES+/Treatment−), and (6) no treatment without exposure to EDES (EDES−/Treatment−). After EDES, the HMWHA group had significantly longer break-up time (BUT) than the 0.1%, 0.3% LMWHA groups and the DQ group. After EDES, the HMWHA group had significantly lower lissamine green staining scores than the LMWHA and DQ groups. Subepithelial presumed dendritic cell density in the HMWHA group was significantly lower than the EDES+/Treatment− group. After EDES exposure, Conjunctival Muc5AC mRNA expression in the HMWHA group was significantly higher than the 0.1 and 0.3% LMWHA groups. Ophthalmic HMWHA solution may have a better dry eye treatment effect than LMWHA or DQ solution, owing to its anti-inflammatory effect.