In vitro analysis of the effects on wound healing of high- and low-molecular weight chains of hyaluronan and their hybrid H-HA/L-HA complexes

Investigating the impact of added Profhilo mesogel to subcision versus subcision monotherapy in treating acne scars; a single-blinded, split-face randomized trial

BACKGROUND

Acne scar is an inflammatory condition, which commonly occurs in patients with acne vulgaris, especially in adults. Mesogels have been reported effective in improving atrophic acne scars.

AIMS

We investigated the efficacy of adding Profhilo (a hyaluronic acid-based filler) to subcision as a new treatment method.

METHODS

Twelve patients aged 18-45 years with atrophic acne scars on both sides of the face participated in this single-blinded, split-face, randomized controlled trial. Each side of the face was randomly assigned to one of the treatment methods, including subcision alone and subcision + Profhilo. Patients in the Profhilo arm received mesogel (1 cc) in addition to the subcision procedure. Both methods were carried out two times at 1-month intervals. Assessments were done based on the sonographic depth of scars, and two blinded observers examined photographs at baseline and 3 months after the final session and the results were reported based on an exclusively made formula as the total score. The Global Improvement Scale and Visual Analogue Scale (VAS) (for patient satisfaction) were also used.

RESULTS

The VAS score of patient satisfaction was statistically significant in the Profhilo arm, with a mean improvement of 528.08 and 219.06 in the subcision arm (p = 0.02). No significant difference was seen in total acne scar reduction comparing the two methods (29.74 in the Profhilo arm and 22.27 in the subcision arm, p = 0.56). Sonographic depth reduction was also non-significant, with a mean of 29.21 in the Profhilo arm and 28.53 in the subcision arm (p = 0.4). The mean global improvement was reported as four in both arms, and no statistical significance was observed (p = 0.89). The best response to treatment belonged to the rolling subtype in both methods (p = 0.029 for the Profhilo arm and p = 0.001 for the subcision arm).

CONCLUSION

Despite no significant difference between the methods, Profhilo is more effective due to a higher satisfaction rate and better physiologic effects.

Biodegradable piezoelectric skin-wound scaffold

Electrical stimulation (ES) induces wound healing and skin regeneration. Combining ES with the tissue-engineering approach, which relies on biomaterials to construct a replacement tissue graft, could offer a self-stimulated scaffold to heal skin-wounds without using potentially toxic growth factors and exogenous cells. Unfortunately, current ES technologies are either ineffective (external stimulations) or unsafe (implanted electrical devices using toxic batteries). Hence, we propose a novel wound-healing strategy that integrates ES with tissue engineering techniques by utilizing a biodegradable self-charged piezoelectric PLLA (Poly (l-lactic acid)) nanofiber matrix. This unique, safe, and stable piezoelectric scaffold can be activated by an external ultrasound (US) to produce well-controlled surface-charges with different polarities, thus serving multiple functions to suppress bacterial growth (negative surface charge) and promote skin regeneration (positive surface charge) at the same time. We demonstrate that the scaffold activated by low intensity/low frequency US can facilitate the proliferation of fibroblast/epithelial cells, enhance expression of genes (collagen I, III, and fibronectin) typical for the wound healing process, and suppress the growth of S. aureus and P. aeruginosa bacteria in vitro simultaneously. This approach induces rapid skin regeneration in a critical-sized skin wound mouse model in vivo. The piezoelectric PLLA skin scaffold thus assumes the role of a multi-tasking, biodegradable, battery-free electrical stimulator which is important for skin-wound healing and bacterial infection prevention simultaneuosly.

Production of isotopically enriched high molecular weight hyaluronic acid and characterization by solid-state NMR

Hyaluronic acid (HA) is a naturally occurring polysaccharide that is abundant in the extracellular matrix (ECM) of all vertebrate cells. HA-based hydrogels have attracted great interest for biomedical applications due to their high viscoelasticity and biocompatibility. In both ECM and hydrogel applications, high molecular weight (HMW)-HA can absorb a large amount of water to yield matrices with a high level of structural integrity. To understand the molecular underpinnings of structural and functional properties of HA-containing hydrogels, few techniques are available. Nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for such studies, e.g. ¹³C NMR measurements can reveal the structural and dynamical features of (HMW) HA. However, a major obstacle to ¹³C NMR is the low natural abundance of ¹³C, necessitating the generation of HMW-HA that is enriched with ¹³C isotopes. Here we present a convenient method to obtain ¹³C- and ¹⁵N-enriched HMW-HA in good yield from Streptococcus equi subsp. zooepidemicus. The labeled HMW-HA has been characterized by solution and magic angle spinning (MAS) solid-state NMR spectroscopy, as well as other methods. These results will open new ways to study the structure and dynamics of HMW-HA-based hydrogels, and interactions of HMW-HA with proteins and other ECM components, using advanced NMR techniques.

Polysaccharide hydrogel platforms as suitable carriers of liposomes and extracellular vesicles for dermal applications

Lipid-based nanocarriers have been extensively investigated for their application in drug delivery. Particularly, liposomes are now clinically established for treating various diseases such as fungal infections. In contrast, extracellular vesicles (EVs) - small cell-derived nanoparticles involved in cellular communication - have just recently sparked interest as drug carriers but their development is still at the preclinical level. To drive this development further, the methods and technologies exploited in the context of liposome research should be applied in the domain of EVs to facilitate and accelerate their clinical translation. One of the crucial steps for EV-based therapeutics is designing them as proper dosage forms for specific applications. This review offers a comprehensive overview of state-of-the-art polysaccharide-based hydrogel platforms designed for artificial and natural vesicles with application in drug delivery to the skin. We discuss their various physicochemical and biological properties and try to create a sound basis for the optimization of EV-embedded hydrogels as versatile therapeutic avenues.

A fabricated hydrogel of hyaluronic acid/curcumin shows super-activity to heal the bacterial infected wound

High risk of acute morbidities and even mortality from expanding the antibiotics resistant infectious wounds force indefinite efforts for development of high performance wound-healing materials. Herein, we design a procedure to fabricate a hyaluronic acid (HA)-based hydrogel to conjugate curcumin (Gel-H.P.Cur). The highlight of this work is to provide a favorite condition for capturing curcumin while protecting its structure and intensifying its activities because of the synchronization with HA. Accordingly, HA as a major component of dermis with a critical role in establishing skin health, could fortify the wound healing property as well as antibacterial activity of the hydrogel. Gel-H.P.Cur showed antibacterial properties against Pseudomonas aeruginosa (P. aeruginosa), which were examined by bactericidal efficiency, disk diffusion, anti-biofilm, and pyocyanin production assays. The effects of Gel-H.P.Cur on the inhibition of quorum sensing (QS) regulatory genes that contribute to expanding bacteria in the injured place was also significant. In addition, Gel-H.P.Cur showed high potential to heal the cutaneous wounds on the mouse excisional wound model with repairing histopathological damages rapidly and without scar. Taken together, the results strongly support Gel-H.P.Cur as a multipotent biomaterial for medical applications regarding the treatment of chronic, infected, and dehiscent wounds.

Self-esterified hyaluronan hydrogels: Advancements in the production with positive implications in tissue healing

Hyaluronan-(HA) short half-life in vivo limits its benefits in tissue repair. Self-esterified-HA is of great interest because it progressively releases HA, promoting tissue-regeneration longer than the unmodified-polymer. Here, the 1-ethyl-3-(3-diethylaminopropyl)carbodiimide(EDC)-hydroxybenzotriazole(HOBt) carboxyl-activating-system was evaluated for self-esterifying HA in the solid state. The aim was to propose an alternative to the time-consuming, conventional reaction of quaternary-ammonium-salts of HA with hydrophobic activating-systems in organic media, and to the EDC-mediated reaction, limited by by-product formation. Additionally, we aimed to obtain derivatives releasing defined molecular-weight(MW)-HA that would be valuable for tissue renewal. A 250 kDa-HA(powder/sponge) was reacted with increasing EDC/HOBt amounts. HA-modification was investigated through Size-Exclusion-Chromatography-Triple-Detector-Array-analyses, FT-IR/¹H NMR and the products(XHAs) extensively characterized. Compared to conventional protocols, the set procedure is more efficient, avoids side-reactions, allows for an easier processing to diverse clinically-usable 3D-forms, leads to products gradually releasing HA under physiological conditions with the possibility to tune the MW of the biopolymer-released. Finally, the XHAs exhibit sound stability to Bovine-Testicular-Hyaluronidase, hydration/mechanical properties suitable for wound-dressings, with improvements over available matrices, and prompt in vitro wound-regeneration, comparably to linear-HA. To the best of our knowledge, the procedure is the first valid alternative to conventional protocols for HA self-esterification with advances in the process itself and in product performance.

Hybrid high- and low-molecular weight chains of hyaluronan is an effective modality treatment for increasing female sexual satisfaction: An interventional, randomized-control parallel study

Background and Aims

Psychological, behavioral, hormonal, surgical, and psychopharmacologic approaches are the only acknowledged treatments for Female Sexual Dysfunction (FSD). The study is conducted to assess the efficacy of hybrid cooperative complexes of high and low molecular weight hyaluronan (hybrid H-HA/L-HA) in treating females with varying of sexual dysfunction and to assess the female genital self-image scale (FGSIS), female sexual function index (FSFI), and dermatology life quality index (DLQI) before and after treatment.

Methods

Sixty female patients were divided into two groups. The study group enrolled 30 female patients injected with hybrid H-HA/L-HA, while the control group enrolled 30 female patients injected with saline. Patients were recruited from the clinic searching for medical advice. Controls were selected from close associates of the cases who were attending with the patients or healthy escorts of dermatology patients attending the dermatology outpatient clinic. We assessed socio-demographic, clinical evaluation, the (FGSIS), (FSFI), and (DLQI) before and after treatment. The first assessment was conducted at the first visit, and the second assessment was conducted after 1 month of the second injection.

Result

Significant increase in the frequency of sexual intercourse/week in the study group after the first and second injection sessions compared to the controls was observed (p < 0.05). There was statistically significant amelioration in desire, arousal, lubrication, orgasm, satisfaction domains, and total score of the FSFI (p ≤ 0.05). The study demonstrated significant increasing differences in all domains of the FGSIS (p ≤ 0.05). The symptoms and feelings, leisure, personal relationships, and total scores were significantly higher post first and second injection of (hybrid H-HA/L-HA) sessions compared to the controls (p < 0.05).

Conclusion

The (hybrid H-HA/L-HA) injection for rejuvenating the genital area appears to be a safe and effective way to enhance female genital self-image, sexuality, and quality of life with high levels of satisfaction as a minimally invasive method.

Molecular weight-dependent hyaluronic acid permeability and tight junction modulation in human buccal TR146 cell monolayers

The oral route is considered an attractive method for drug delivery, as it avoids the hepatic and intestinal first-pass metabolism processes. Hyaluronic acid (HA) beneficial effects to the human body include anti-aging and wound healing but its effects on oral barrier integrity and mechanical function have not yet been investigated. In this study, we analyzed oral barrier integrity and the paracellular pathway of HA transportation in TR146 cell monolayers during and after permeation and using low molecular weight HA (LMW-HA, <100 kDa) and high molecular weight HA (HMW-HA, >500 kDa). Cytotoxicity assays in TR146 cells revealed that neither LMW-HA or HMW-HA altered cell viability at concentrations <0.5 % during 24 h of treatment. HA-treated TR146 cell monolayers showed enhanced oral barrier integrity and reduced apparent permeability of fluorescein. Moreover, HA significantly increased tight junction (TJ)-related genes expression, including ZO-2, marvelD3, cingulin, claudin-1, claudin-3, and claudin-4 expression. Overall, the results of the present study indicate that HA can permeate across the oral barrier and enhance oral barrier function via the upregulated expression of TJ-related genes.

Efficacy of injecting hybrid cooperative complexes of hyaluronic acid for the treatment of vulvar lichen sclerosus: A preliminary study

BACKGROUND

Lichen sclerosus is a chronic relapsing inflammatory skin disease, which involves most commonly the anogenital region. The gold standard in treatment is ultra-potent topical steroids (clobetasol propionate): it aims at controlling the symptoms, stopping further scarring and distortion, and reducing the risk of cancer.

OBJECTIVES

The aim of this preliminary study is to evaluate the efficacy of injecting Hybrid Cooperative Complexes of Hyaluronic Acid (HCC) for the treatment of vulvar lichen sclerosus (VLS).

METHODS

Twenty female adult patients (range: 21-78 years), aged over 18, with histopathological diagnosis of lichen sclerosus and good general conditions were enrolled. Patients underwent HCC infiltration every month, for 3 times. Patients were evaluated at baseline (T0) and after one (T1) and six months (T2) after treatment. During every visit, each patient was studied clinically and with videothermography. Itching, burning sensation, pain, and dyspareunia were reported by patients at T0, T1, and T2. The effectiveness of the treatment on patients' quality of life and sexual function was evaluated using the Dermatology Life Quality Index (DLQI) and the Female Sexual Function Index (FSFI) at T0 and at T2.

RESULTS

The results of this preliminary study are very promising, in fact, all patients had a significant reduction in most symptoms after 1 and 6 months of HCC treatment. The reduction of patients with itching (p value ≤ 0.001), pain (p value = 0.031), and burning sensation (p = 0.004) at 6 months is significant. The analysis of DLQI scores revealed a significant improvement in patients' quality of life. At baseline, the average score of DLQI (±SD) was 5.89 ± 3.68 while at follow-up it was 3.42 ± 2.36 (p = 0.002).

CONCLUSIONS

Our preliminary study has demonstrated the validity and tolerability of HCC infiltrations in patients with VLS, and the effectiveness of HCC in reducing symptoms and, thus, to improve sexuality and patient quality of life.

Fabrication and in vitro characterization of zinc oxide nanoparticles and hyaluronic acid-containing carboxymethylcellulose gel for wound healing application

Chronic wounds, such as burns and diabetic ulcers, are complex wounds sustained by the skin that require life-long rehabilitation and have the potential to deteriorate and get infected. The number of patients with this ailment has been steadily increasing. This illness demands the use of new dressings with the best capabilities for managing wound healing. This study created an gel with carboxymethylcellulose (CMC), hyaluronic acid (HA), and zinc oxide nanoparticles (ZnO NPs). According to the findings, the manufacturing technique with a 1:4 ratio of HA and CMC gel had the best viscosity. Additionally, varying concentrations of zinc oxide nanoparticles (ZnO NPs) were added to the formula. Variations included 0.05, 0.125, 0.5, 1.0, 3.0, 5.0, and 10% by weight. In order to find the ideal dose and formulation, physical properties, an anti-bacterial test, and a cell migration assay were carried out. The samples with concentration of 0.5, 1.0, 3.0, 5.0 and 10% w/v showed ability to kill gram-positive and gram-negative bacteria. Wound healing experiments showed that cells proliferated for HA/CMC/ZnO gel with a weight-to-volume ratio of 0.05% and 1.0% w/v. In conclusion, according to all (physical and biological) characterization, the HA/CMC/ZnO gel with a weight-to-volume ratio of 1.0% w/v was found to have a considerable standard for wound-healing materials, demonstrating a promising effect against bacteria.

Fabrication of Low-Molecular-Weight Hyaluronic Acid-Carboxymethyl Cellulose Hybrid to Promote Bone Growth in Guided Bone Regeneration Surgery: An Animal Study

Guided bone regeneration surgery is an important dental operation used to regenerate enough bone to successfully heal dental implants. When this technique is performed on maxilla sinuses, hyaluronic acid (HLA) can be used as an auxiliary material to improve the graft material handling properties. Recent studies have indicated that low-molecular hyaluronic acid (L-HLA) provides a better regeneration ability than high-molecular-weight (H-HLA) analogues. The aim of this study was to fabricate an L-HLA-carboxymethyl cellulose (CMC) hybrid to promote bone regeneration while maintaining viscosity. The proliferation effect of fabricated L-HLA was tested using dental pulp stem cells (DPSCs). The mitogen-activated protein kinase (MAPK) pathway was examined using cells cultured with L-HLA combined with extracellular-signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 inhibitors. The bone growth promotion of fabricated L-HLA/CMC hybrids was tested using an animal model. Micro-computer tomography (Micro-CT) and histological images were evaluated quantitatively to compare the differences in the osteogenesis between the H-HLA and L-HLA. Our results show that the fabricated L-HLA can bind to CD44 on the DPSC cell membranes and affect MAPK pathways, resulting in a prompt proliferation rate increase. Micro CT images show that new bone formation in rabbit calvaria defects treated with L-HLA/CMC was almost two times higher than in defects filled with H-HLA/CMC (p < 0.05) at 4 weeks, a trend that remained at 8 weeks and was confirmed by HE-stained images. According to these findings, it is reasonable to conclude that L-HLA provides better bone healing than H-HLA, and that the L-HLA/CMC fabricated in this study is a potential candidate for improving bone healing efficiency when a guided bone regeneration surgery was performed.

Dissolving microneedles for long-term storage and transdermal delivery of extracellular vesicles

Extracellular vesicles (EVs) have shown great potential in disease diagnosis and treatment; however, their clinical applications remain challenging due to their unsatisfactory long-term stability and the lack of effective delivery strategies. In this study, we prepared human adipose stem cell-derived EV (hASC-EV)-loaded hyaluronic acid dissolving microneedles (EV@MN) to investigate the feasibility of EVs for their clinical applications. The biological activities of the EVs in this formulation were maintained for more than six months under mild storage conditions, especially at temperatures lower than 4 °C. Moreover, the EV@MN enabled precise and convenient intradermal delivery for sustained release of EVs in the dermis layer. Therefore, EV@MN significantly improved the biological functions of hASC-EVs on dermal fibroblasts by promoting syntheses of proteins for the extracellular matrix such as collagen and elastin, enhancing fibroblast proliferation, and regulating the phenotype of fibroblast, compared with other administration methods. This research revealed a possible and feasible formulation for the clinical application of EVs.

Treatment of Delayed-onset Inflammatory Reactions to Hyaluronic Acid Filler: An Algorithmic Approach

Hyaluronic acid fillers are one of the most widely used and versatile fillers worldwide. Although traditionally regarded as immunologically inert, many currently available products have been substantially modified to improve longevity and to optimize properties for specific indications. Such modifications, either alone or in combination with other factors (such as the immune status of the patient, immune-triggering events, and bacterial contamination), may lead to the development of late-onset inflammatory nodules in some patients. This article discusses the clinical presentation of late-onset adverse inflammatory reactions to hyaluronic acid injections, describes their likely triggers, and presents the author's treatment algorithm for successful resolution.

A Review of the Clinical Effectiveness and Safety of Hybrid Cooperative Complexes in Intra-articular Viscosupplementation

Viscosupplementation by intra-articular (i.a.) injection of the non-sulfated glycosaminoglycan (GAG) hyaluronic acid (HA) is a conservative therapy widely accepted in clinical practice for the management of osteoarthritis (OA) and joint diseases. The aim of viscosupplementation is to restore the rheological properties of the synovial fluid to relieve joint inflammation and pain and improve joint function through a chondroprotective effect. However, there is a range of hyaluronic acid products for OA that differ in preparation, molecular weight, rheological characteristics and concentration, and different i.a. formulations are more suited to particular patient populations and clinical situations, in part because of anatomical differences between joints. This paper focuses on innovative hybrid cooperative complexes of high and low molecular weight hyaluronic acid (HA-HL) and hyaluronic acid plus sodium chondroitin (HA-SC) that have been developed. Both products are formulated with pharmaceutical-grade, highly purified hyaluronic acid obtained with a multi-step biofermentation process, with properties that make them suitable across a range of degenerative joint diseases. They represent progress in building on the symptomatic and functional benefits of viscosupplementation in joint disease, with the additional beneficial effect of treating the patient with a high concentration of GAGs by a low number of injections. Here, we review the clinical evidence for the efficacy of a hybrid cooperative compound of HA-HL in various degenerative joint diseases, which suggests a synergistic effect of the different molecular weight hyaluronans that together more closely mimic the physiological composition of synovial fluid. Similarly, the evidence shows that HA-SC is safe, effective, and well tolerated in hip OA, with rapid and clinically significant improvements in pain symptoms and functionality. Such innovations in viscosupplementation expand the usefulness of the modality in the management of OA and other joint diseases, complemented by a lack of systemic or local side effects that allow the concurrent use of other drugs if needed.

Potential of Biofermentative Unsulfated Chondroitin and Hyaluronic Acid in Dermal Repair

Chondroitin obtained through biotechnological processes (BC) shares similarities with both chondroitin sulfate (CS), due to the dimeric repetitive unit, and hyaluronic acid (HA), as it is unsulfated. In the framework of this experimental research, formulations containing BC with an average molecular size of about 35 KDa and high molecular weight HA (HHA) were characterized with respect to their rheological behavior, stability to enzymatic hydrolysis and they were evaluated in different skin damage models. The rheological characterization of the HHA/BC formulation revealed a G’ of 92 ± 3 Pa and a G″ of 116 ± 5 Pa and supported an easy injectability even at a concentration of 40 mg/mL. HA/BC preserved the HHA fraction better than HHA alone. BTH was active on BC alone only at high concentration. Assays on scratched keratinocytes (HaCaT) monolayers showed that all the glycosaminoglycan formulations accelerated cell migration, with HA/BC fastening healing 2-fold compared to the control. In addition, in 2D HaCaT cultures, as well as in a 3D skin tissue model HHA/BC efficiently modulated mRNA and protein levels of different types of collagens and elastin remarking a functional tissue physiology. Finally, immortalized human fibroblasts were challenged with TNF-α to obtain an in vitro model of inflammation. Upon HHA/BC addition, secreted IL-6 level was lower and efficient ECM biosynthesis was re-established. Finally, co-cultures of HaCaT and melanocytes were established, showing the ability of HHA/BC to modulate melanin release, suggesting a possible effect of this specific formulation on the reduction of stretch marks. Overall, besides demonstrating the safety of BC, the present study highlights the potential beneficial effect of HHA/BC formulation in different damage dermal models.

IGF-I and Hyaluronic Acid Mitigate the Negative Effect of Irradiation on Human Skin Keratinocytes

Simple Summary

Patients undergoing radiation therapy for the treatment of various types of cancer often experience side effects such as radiation dermatitis. A gold standard treatment is still lacking. The objective of the present study was to find novel therapeutic strategies for the regeneration and repair of damaged skin areas after irradiation. An in vitro 2D and 3D primary keratinocyte model was used to test the effect of insulin-like growth factor I (IGF-I), keratinocyte growth factor (KGF), platelet lysate (PL), hyaluronic acid (HA), and adipose-derived stem cell (ADSC) conditioned medium on the functional abilities (viability, migration) and the gene expression of irradiated keratinocytes. Hyaluronic acid and IGF-I effectively reduced the irradiation damage of primary keratinocytes by stimulating viability and migration and reducing cell apoptosis and necrosis. These findings indicate that the negative effects of irradiation on keratinocytes located in the patient’s skin can be counterbalanced with HA and IGF-I treatment.

Abstract

Ionizing radiation has become an integral part of modern cancer therapy regimens. Various side effects, such as radiation dermatitis, affect patients in acute and chronic forms and decrease therapy compliance significantly. In this study, primary keratinocytes were irradiated in a 2-dimensional (2D) culture as well as on a 3-dimensional (3D) collagen-elastin matrix with doses of 2 and 5 Gy. The effect of different concentrations of IGF-I, KGF, platelet lysate (PL), high and low molecular weight hyaluronic acid (H-HA, L-HA), and adipose-derived stem cell (ADSC) conditioned medium was analyzed in respect to cell viability (WST-8), wound closure (migration), and the gene expression (quantitative real-time PCR) of 2D cultures. The 3D culture was evaluated by WST-8. A mixture of H-HA and L-HA, as well as IGF-I, could significantly stimulate the keratinocyte viability and migration which were severely reduced by irradiation. The MKI67and IL6 gene expression of irradiated keratinocytes was significantly higher after H-HA/L-HA treatment. The stimulating effects of H-HA/L-HA and IGF-I were able to be confirmed in 3D culture. A positive influence on cell viability, migration, and gene expression was achieved after the treatment with H-L-HA and IGF-I. These results open the possibility of a novel therapeutic method for both the prevention and the treatment of radiation dermatitis.

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.

Further structural characterization of ovine forestomach matrix and multi-layered extracellular matrix composites for soft tissue repair

Decellularized extracellular matrix (dECM)-based biomaterials are of great clinical utility in soft tissue repair applications due to their regenerative properties. Multi-layered dECM devices have been developed for clinical indications where additional thickness and biomechanical performance are required. However, traditional approaches to the fabrication of multi-layered dECM devices introduce additional laminating materials or chemical modifications of the dECM that may impair the biological functionality of the material. Using an established dECM biomaterial, ovine forestomach matrix, a novel method for the fabrication of multi-layered dECM constructs has been developed, where layers are bonded via a physical interlocking process without the need for additional bonding materials or detrimental chemical modification of the dECM. The versatility of the interlocking process has been demonstrated by incorporating a layer of hyaluronic acid to create a composite material with additional biological functionality. Interlocked composite devices including hyaluronic acid showed improved in vitro bioactivity and moisture retention properties.

Tumor-Associated Extracellular Matrix: How to Be a Potential Aide to Anti-tumor Immunotherapy?

The development of cancer immunotherapy, particularly immune checkpoint blockade therapy, has made major breakthroughs in the therapy of cancers. However, less than one-third of the cancer patients obtain significant and long-lasting therapeutic effects by cancer immunotherapy. Over the past few decades, cancer-related inflammations have been gradually more familiar to us. It’s known that chronic inflammation in tumor microenvironment (TME) plays a predominant role in tumor immunosuppression. Tumor-associated extracellular matrix (ECM), as a core member of TME, has been a research hotspot recently. A growing number of studies indicate that tumor-associated ECM is one of the major obstacles to realizing more successful cases of cancer immunotherapy. In this review, we discussed the potential application of tumor-associated ECM in the cancer immunity and its aide potentialities to anti-tumor immunotherapy.

Absorption, distribution, metabolism and excretion of hyaluronic acid during pregnancy: a matter of molecular weight

INTRODUCTION

For many years hyaluronic acid (HA) was mainly used for its hydrating properties. However, new applications have recently arisen, considering the biological properties of HA and its molecular weight. Clinical application of low molecular weight HA (LMW-HA) initially was supported by specific absorption data. The identification of high molecular weight HA (HMW-HA) absorption pathways and the knowledge of its physiological role allowed to evaluate its clinical application. Based on the immunomodulatory properties of HMW-HA and its physiological involvement as signaling molecule, pregnancy represents an interesting context of application.

AREA COVERED

This expert opinion includes in-vitro, in-vivo, ex-vivo and clinical studies on gestational models. It provides an overview of the physiological and the therapeutic role of HMW-HA in pregnancy starting from its metabolism. Indeed, HMW-HA is widely involved in several physiological processes as implantation, immune response, uterine quiescence and cervical remodeling, and therefore is an essential molecule for a successful pregnancy.

EXPERT OPINION

Available evidence suggests that HMW-HA administration can support physiological pregnancy, favoring blastocyst adhesion and development, preventing miscarriage and pre-term birth. For this reason, supplementation in pregnancy should be evaluated.

Estimation of the Effect of Accelerating New Bone Formation of High and Low Molecular Weight Hyaluronic Acid Hybrid: An Animal Study

Osteoconduction is an important consideration for fabricating bio-active materials for bone regeneration. For years, hydroxyapatite and β-calcium triphosphate (β-TCP) have been used to develop bone grafts for treating bone defects. However, this material can be difficult to handle due to filling material sagging. High molecular weight hyaluronic acid (H-HA) can be used as a carrier to address this problem and improve operability. However, the effect of H-HA on bone formation is still controversial. In this study, low molecular weight hyaluronic acid (L-HA) was fabricated using gamma-ray irradiation. The viscoelastic properties and chemical structure of the fabricated hybrids were evaluated by a rheological analysis nuclear magnetic resonance (NMR) spectrum. The L-MH was mixed with H-HA to produce H-HA/L-HA hybrids at ratios of 80:20, 50:50 and 20:80 (w/w). These HA hybrids were then combined with hydroxyapatite and β-TCP to create a novel bone graft composite. For animal study, artificial bone defects were prepared in rabbit femurs. After 12 weeks of healing, the rabbits were scarified, and the healing statuses were observed and evaluated through micro-computer tomography (CT) and tissue histological images. Our viscoelastic analysis showed that an HA hybrid consisting 20% H-HA is sufficient to maintain elasticity; however, the addition of L-HA dramatically decreases the dynamic viscosity of the HA hybrid. Micro-CT images showed that the new bone formations in the rabbit femur defect model treated with 50% and 80% L-HA were 1.47 (p < 0.05) and 2.26 (p < 0.01) times higher than samples filled with HA free bone graft. In addition, a similar tendency was observed in the results of HE staining. These results lead us to suggest that the material with an H-HA/L-HA ratio of 50:50 exhibited acceptable viscosity and significant new bone formation. Thus, it is reasonable to suggest that it may be a potential candidate to serve as a supporting system for improving the operability of granular bone grafts and enhancing new bone formations.

Chondroitin Sulfate in USA Dietary Supplements in Comparison to Pharma Grade Products: Analytical Fingerprint and Potential Anti-Inflammatory Effect on Human Osteoartritic Chondrocytes and Synoviocytes

The biological activity of chondroitin sulfate (CS) and glucosamine (GlcN) food supplements (FS), sold in USA against osteoarthritis, might depend on the effective CS and GlcN contents and on the CS structural characteristics. In this paper three USA FS were compared to two pharmaceutical products (Ph). Analyses performed by HPAE-PAD, by HPCE and by SEC-TDA revealed that the CS and GlcN titers were up to −68.8% lower than the contents declared on the labels and that CS of mixed animal origin and variable molecular weights was present together with undesired keratan sulfate. Simulated gastric and intestinal digestions were performed in vitro to evaluate the real CS amount that may reach the gut as biopolymer. Chondrocytes and synoviocytes primary cells derived from human pathological joints were used to assess: cell viability, modulation of the NF-κB, quantification of cartilage oligomeric matrix protein (COMP-2), hyaluronate synthase enzyme (HAS-1), pentraxin (PTX-3) and the secreted IL-6 and IL-8 to assess inflammation. Of the three FS tested only one (US FS1) enhanced chondrocytes viability, while all of them supported synoviocytes growth. Although US FS1 proved to be less effective than Ph as it reduced NF-kB, it could not down-regulate COMP-2; HAS-1 was up-regulated but with a lower efficacy. Inflammatory cytokines were markedly reduced by Ph while a slight decrease was only found for US-FS1.

Paris saponin H inhibits the proliferation of glioma cells through the A1 and A3 adenosine receptor‑mediated pathway

Paris saponin H (PSH) is a type of steroid saponin derived from Rhizoma Paridis (RP; the rhizome of Paris). In our previous studies, saponins from RP exerted antiglioma activity in vitro. However, the effects of PSH on glioma have not been elucidated. The aim of the present study was to evaluate the effects of PSH on U251 glioblastoma cells and elucidate the possible underlying mechanism. The cells were treated with PSH at various concentrations for 48 h, and the cell viability, invasion, apoptosis and cycle progression were assessed using specific assay kits. The activation of Akt, 44/42‑mitogen‑activated protein kinase (MAPK) and the expression levels of A1 adenosine receptor (ARA1) and ARA3 were assessed by western blotting. The results demonstrated that PSH inhibited cell viability, migration and invasion, and induced apoptosis. Treatment of U251 cells with PSH induced the upregulation of p21 and p27, and the downregulation cyclin D1 and S‑phase kinase associated protein 2 protein expression levels, which induced cell cycle arrest at the G1 phase. The results also demonstrated that PSH inhibited the expression of ARA1, and the agonist of ARA1, 2‑chloro‑N6‑cyclopentyladenosine, reversed the effects of PSH. Hypoxia induced increases in the ARA3, hypoxia‑inducible factor‑1α (HIF‑1α) and vascular endothelial growth factor (VEGF) protein expression levels, which were associated with the activation of the Akt and P44/42 MAPK pathways. Compared with the hypoxia group, PSH inhibited the expression levels of ARA3, HIF‑1α and VEGF, as well as the phosphorylation levels of Akt and 44/42 MAPK, and repressed HIF‑1α transcriptional activity. Furthermore, the results demonstrated that PSH inhibited the expression of HIF‑1α by inhibiting the phosphorylation of Akt and 44/42 MAPK mediated by ARA3. Taken together, these results suggested that PSH reduced U251 cell viability via the inhibition of ARA1 and ARA3 expression, and further inhibited Akt and 44/42 MAPK phosphorylation, induced apoptosis and cell cycle arrest.

Hyaluronic acid electrospinning: Challenges, applications in wound dressings and new perspectives

Hyaluronic acid (HA) has already been consolidated in the literature as an extremely efficient biopolymer for biomedical applications. In addition to its biodegradability, HA also has excellent biological properties. In the nanofiber form, this polymer can mimic biological tissues, mainly the layers of the skin, and therefore has great potential as structures for the construction of wound dressings. Despite the numerous efforts from the scientific community proposing new dressings, this is an area in constant evolution. A dressing that brings together all the properties of an ideal dressing has not been developed yet. Electrospinning is a simple and versatile technique that correctly aligned with the functional properties of HA can produce multifunctional nanofiber structures capable of promoting skin recover quickly. This review discusses (i) key strategies for successful electrospinning of HA, (ii) main challenges and advances found in the electrospinning process, (iii) the bioactive properties of this polymer in the treatment of wounds, as well as (iv) the results obtained in the last decade by the in vitro and in vivo evaluation of the healing properties of these nanosystems.

Preparation of 6-carboxyl chitin and its effects on cell proliferation in vitro

This study concerns the performance evaluation of 6-carboxyl chitin for its wound healing application. 6-Carboxyl chitins were prepared by the oxidation of chitin at C-6 with NaClO/TEMPO/NaBr after α-chitin was pretreated in NaOH/urea solution. The products with different molecular weights were obtained by changing reaction conditions. They all were completely oxidized at C-6 and N-acetylated at C-2 according to FT-IR and NMR results. 6-Carboxyl chitins could stimulate significantly the proliferation of human skin fibroblasts (HSF) and human keratinocytes (HaCaT), and the bioactivities were concentration and Mws dependent. Within the scope of the study, 10-40 kDa of Mws and 10-100 μg/mL of concentrations were most suitable for the HSF proliferation, but the proliferation of HaCaT increased with decreasing the concentration and Mw. In addition, 6-carboxyl chitins could also induce macrophages and fibroblasts to secrete growth factors. Therefore, 6-carboxyl chitins could be expected to be an active ingredient for wound healing.

Effect of hyaluronic acid on paracrine signaling of osteoblasts from mesenchymal stromal cells: potential impact on bone regeneration

OBJECTIVES

This study evaluated hyaluronic acids (HA) with different molecular weights as potential matrices for tissue-engineered bone grafting and their possible influence on the paracrine mechanisms of adipose-derived mesenchymal stromal cells.

MATERIAL AND METHODS

Murine adipose mesenchymal stromal cells (mASCs) on the fourth passage were seeded in 96-well plates, osteoinduced for 27 days and exposed for 3 days to low (HA-LW) and high/low molecular weight (HA-HLW) at previously defined concentrations. Cytokines IGF-1, VEGF, FGF-2, and BMP-2 were evaluated by quantification in the supernatant.

RESULTS

Greater expression of growth factors was observed in groups with HA-HLW compared to HA-LW. Results indicated that differentiated cells secreted fewer cytokines, namely VEGF, FGF, and BMP-2 than undifferentiated mASCs (p < 0.05). IGF-1 showed its greatest expression in the mASC HA-LW group (p < 0.05).

CONCLUSIONS

The application of HA-HLW as cell matrix in tissue engineering did not compromise mASC paracrine effect. Also, the association of HA-HLW matrix and mASCs resulted in greater expression of osteogenic growth factors. Longer periods of cell differentiation seemed to negatively affect their capacity for local paracrine stimulation.

CLINICAL RELEVANCE

The use of HA-HLW as matrix for undifferentiated ASCs can be positive for bone regeneration, favoring its application as cell matrix in bone grafting procedures.

The Leaf Extract of Coccinia grandis (L.) Voigt Accelerated In Vitro Wound Healing by Reducing Oxidative Stress Injury

The impairment in the regulation of the physiological process in the inflammatory phase of wound healing results in oxidative stress damage, which increases the severity and extends the healing time. In this study, we aimed to evaluate the radical scavenging properties of Coccinia leaf extract and its ability to ameliorate a migration process in vitro. Coccinia is a medicinal plant that was used in ancient times for relieving insect bite itching and swelling. However, the role of Coccinia leaf extract as an antioxidant related to the process of wound healing has never been studied. In this study, we demonstrated that the leaf extract possessed antioxidant properties that acted as a proton donor to neutralize reactive oxygen species with the IC₅₀ value of 4.85 mg/mL of the extract. It could chelate iron with the IC₅₀ value of 21.39 mg/mL of the extract. The leaf extract protected the human fibroblasts and keratinocytes from hydrogen peroxide-induced oxidative stress by increasing cell survival rate by more than 20% in all test doses. The protective property was dose-dependently correlated with the decrease in reactive oxygen species formation. In addition, the leaf extract enhanced the cell migration rate of fibroblasts and keratinocytes up to 23% compared with vehicle control. The results suggested that Coccinia leaf extract may be a potential herb for increasing the wound healing process with its antioxidant capacity and can be used as an herbal ingredient for the utilization of skincare products.

Effect of Glycosaminoglycan Replacement on Markers of Interstitial Cystitis In Vitro

Aims: To examine the effect of three commercial intravesical formulations of glycosaminoglycan on in vitro inflammatory models of IC/BPS to better understand there effect on specific markers of disease.

Methods: Human urothelial cells (HTB-4) were cultured under four conditions in the presence or absence of commercial GAG formulations. Cells were cultured under a basal condition or pre-treated with protamine sulfate (100 ng/ml) (damages the endogenous glycosaminoglycan layer), hydrogen peroxide (1%) (a metabolic stressor) or TNFα (10 ng/ml) (creating an inflammatory environment). Each of these four culture conditions was then treated with one of three GAG formulations, CystistatⓇ, iAluRilⓇ and HyacystⓇ. Assays were then performed to examine the effect of the exogenous GAGs on cell viability, cell migration, sGAG production, cytokine and gene expression.

Results: All GAG formulations were well tolerated by the HTB-4 cells and supported cell growth and migration. iAluRilⓇ was most effective at stimulating endogenous sGAG production under all conditions, increasing sGAGs by up to 15-fold. All GAG formulations significantly reduced the production of the pro-inflammatory cytokine IL-8 under basal conditions, while no GAG treatment suppressed cytokine production under any other condition. Only Cystistat^Ⓡ had a significant effect on HA receptor expression, significantly increasing ICAM-1 expression at 3 h that returned to basal levels at 24 h. No GAG treatment significantly changed the expression of GAG synthesis enzymes (CSGALNACT1, CSGALNACT2) or markers of tissue remodeling (MMP2, TIMP1) and pain (COX-1/PTGS-1, NGF).

Conclusions: The data presented in this study reveal that commercial intravesical formulation support cell viability and migration. In addition, the commercial GAG formulations have a mild anti-inflammatory effect in the in vitro model of interstitial cystitis/bladder pain syndrome.

Combined autologous platelet-rich plasma with microneedling versus microneedling with non-cross-linked hyaluronic acid in the treatment of atrophic acne scars: Split-face study

Acne scarring causes cosmetic discomfort, depression, low self-esteem and reduced quality of life. Microneedling is an established treatment for scars. A multimodality approach to scar treatment is usually necessary to achieve the best cosmetic results. The objective of this study was to evaluate the efficacy and safety of platelet rich plasma (PRP) combined with microneedling in comparison with microneedling with non-cross-linked hyaluronic acid for the treatment of atrophic acne scars. Forty-one patients of 20-40 years of age with atrophic acne scars were included. Microneedling was performed on both halves of the face. Topical application of PRP was given on right half of the face, while the left half of the face was treated with topical application of non-cross-linked hyaluronic acid. Four treatment sessions were given at an interval of 1 month consecutively. Goodman's Qualitative scale and the quartile grading scale are used for the final evaluation of results. There was a statistically significant improvement in acne scars after treatment among the studied group. Right and left halves showed 85.4% and 82.9% improvement, So the difference of the improvement between the two modalities is statistically insignificant P > 0.05 We conclude that microneedling has efficacy in the management of atrophic acne scars. It can be combined with either PRP or noncross-linked hyaluronic acid to enhance the final clinical outcomes in comparison with microneedling alone. The difference between the two modalities is insignificant.

Dose- and time-dependent effects of hyaluronidase on structural cells and the extracellular matrix of the skin

Introduction

Hyaluronic acid (hyaluronan; HA) is an essential component of the extracellular matrix (ECM) of the skin. The HA-degrading enzyme hyaluronidase (HYAL) is critically involved in the HA-metabolism. Yet, only little information is available regarding the skin’s HA–HYAL interactions on the molecular and cellular levels.

Objective

To analyze the dose- and time-dependent molecular and cellular effects of HYAL on structural cells and the HA-metabolism in the skin.

Materials and methods

Chip-based, genome-wide expression analyses (Affymetrix® GeneChip PrimeView™ Human Gene Expression Array), quantitative real-time PCR analyses, enzyme-linked immunosorbent assay (ELISA), immunohistochemistry (DAB), and in vitro wound healing assays were performed to assess dose-dependent and time-kinetic effects of HA and HYAL (bovine hyaluronidase, Hylase “Dessau”) on normal human dermal fibroblasts (NHDF), primary human keratinocytes in vitro and human skin samples ex vivo.

Results

Genome-wide expression analyses revealed an upregulation of HA synthases (HAS) up to 1.8-fold change in HA- and HYAL-treated NHDF. HA and HYAL significantly accelerated wound closure in an in vitro model for cutaneous wound healing. HYAL induced HAS1 and HAS2 mRNA gene expression in NHDF. Interestingly, low concentrations of HYAL (0.015 U/ml) resulted in a significantly higher induction of HAS compared to moderate (0.15 and 1.5 U/ml) and high concentrations (15 U/ml) of HYAL. This observation corresponded to increased concentrations of HA measured by ELISA in conditioned supernatants of HYAL-treated NHDF with the highest concentrations observed for 0.015 U/ml of HYAL. Finally, immunohistochemical analysis of human skin samples incubated with HYAL for up to 48 h ex vivo demonstrated that low concentrations of HYAL (0.015 U/ml) led to a pronounced accumulation of HA, whereas high concentrations of HYAL (15 U/ml) reduced dermal HA-levels.

Conclusion

HYAL is a bioactive enzyme that exerts multiple effects on the HA-metabolism as well as on the structural cells of the skin. Our results indicate that HYAL promotes wound healing and exerts a dose-dependent induction of HA-synthesis in structural cells of the skin. Herein, interestingly the most significant induction of HAS and HA were observed for the lowest concentration of HYAL.

Q-switched Nd-YAG laser alone and in combination with innovative hyaluronic acid gels improve keratinocytes wound healing in vitro

During the last years, several attempts have been accomplished to improve the wound healing. Device application aimed at enhancing skin ability to reconstruct its damaged sites through a proper dermal regenerative process. In particular, Q-switched Nd-YAG laser (Medlite C6 laser, Conbio, USA) applied with a fluence of 8 J/cm², a pulse width of 5 ns, and a spot size of 4 mm exerts a photo-mechanical action that improve skin repair. Besides, hyaluronan hybrid cooperative complexes (HCC) widely exploited in dermoesthetic applications proved specific actions on keratinocytes and fibroblasts monolayer repair. We evaluated this specific laser treatment in vitro on a wound healing model based on human keratinocytes (HaCaT) alone and in combination with HCC. In addition, we evaluated key biomarkers of dermal repair. Scratched HaCaT monolayers were treated with laser and successively with HA-based formulations (HHA and HCC). For each treatment and the control samples, at least 3 different wells were analyzed. Wound closure was quantified, measuring five view filed for each well at increasing incubation time, exploiting time lapse videomicroscopy and image analysis, permitting to compare the different healing rate of treatments respect to control. By real-time PCR and western blotting, we evaluated biomarkers of wound regeneration, such as integrins, aquaporin three (AQP3), and proinflammatory cytokines. The ANOVA test was used to assess statistical significance of the results obtained. Laser-treated cells achieved wound closure in about 37 h, faster than the control, while when coupled to HCC, the complete reparation was obtained in 24 h. Integrin αV was upregulated by treatments, with in particular about four-fold increase respect to the control when HCC + laser was used. In addition, integrin β3 was upregulated by all treatments especially with the combination of laser and HCC proved more efficient than others (~ 14-folds). A slighter but significant increase of AQP3 gene expression of 61% was found for laser treatment while the latter combined with HCC determined an upregulation of 72%. By coupling laser treatment and HCC, further healing improvement and consistent biomarker modulation was observed. Our results may support clinical implementation of new dermatology protocols conjugating laser treatments with topical or injective HA formulations as a valid tool in treatments to repair scars or other skin defects.

An in vitro study to assess the effect of hyaluronan-based gels on muscle-derived cells: Highlighting a new perspective in regenerative medicine

Hyaluronan (HA) is a nonsulfated glycosaminoglycan that has been widely used for biomedical applications. Here, we have analyzed the effect of HA on the rescue of primary cells under stress as well as its potential to recover muscle atrophy and validated the developed model in vitro using primary muscle cells derived from rats. The potentials of different HAs were elucidated through comparative analyses using pharmaceutical grade a) high (HHA) and b) low molecular weight (LHA) hyaluronans, c) hybrid cooperative complexes (HCC) of HA in three experimental set-ups. The cells were characterized based on the expression of myogenin, a muscle-specific biomarker, and the proliferation was analyzed using Time-Lapse Video Microscopy (TLVM). Cell viability in response to H₂O₂ challenge was evaluated by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, and the expression of the superoxide dismutase enzyme (SOD-2) was assessed by western blotting. Additionally, in order to establish an in vitro model of atrophy, muscle cells were treated with tumor necrosis factor-alpha (TNF-α), along with hyaluronans. The expression of Atrogin, MuRF-1, nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-kB), and Forkhead-box-(Fox)-O-3 (FoxO3a) was evaluated by western blotting to elucidate the molecular mechanism of atrophy. The results showed that HCC and HHA increased cell proliferation by 1.15 and 2.3 folds in comparison to un-treated cells (control), respectively. Moreover, both pre- and post-treatments of HAs restored the cell viability, and the SOD-2 expression was found to be reduced by 1.5 fold in HA-treated cells as compared to the stressed condition. Specifically in atrophic stressed cells, HCC revealed a noteworthy beneficial effect on the myogenic biomarkers indicating that it could be used as a promising platform for tissue regeneration with specific attention to muscle cell protection against stressful agents.

Short-Term Effect of a New Oral Sodium Hyaluronate Formulation on Knee Osteoarthritis: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial

Objective: the aim of this pilot study was to test the short-term effect of oral supplementation with a sodium hyaluronate with a large spectrum of molecular weights (FS-HA^®) on the symptoms and functionality of knee osteoarthritis (OA). Methods: 60 subjects affected by clinical and/or radiological diagnosis of symptomatic knee OA were consecutively enrolled in a randomized, double blind, placebo-controlled, clinical trial. At randomization visit, at day 28 (visit 2), and day 56 (visit 3), the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), the Lequesne Functional Index (LFI) and the Visual Analogue Scale (VAS) for pain (VAS-p) were administered to the enrolled patients. Then, patients were asked how many times they used rescue medications (non-steroidal antinflammatory drugs–NSAIDs and/or anti-pain drugs) during the previous 4 weeks. Finally, the range of knee joint motion (ROM) was also instrumentally measured. Results: In FS-HA^® treated subjects, VAS-p, pain and total WOMAC score, LFI and ROM significantly improved compared to the baseline values (p < 0.05). At 60 days, the VAS-p and the pain WOMAC score were significantly lower after FS-HA^® treatment when compared with placebo as well (p < 0.05). The FS-HA^® treated subjects significantly reduced the weekly use of NSAIDs and/or antipain drugs when compared to the placebo-treated ones (p < 0.05). Conclusion: the oral supplementation with a FS-HA^® characterized by a large spectrum of molecular weight was associated with a short-term improvement in symptomatology and functionality of osteoarthritis-affected knees, and associated with a reduction in the use of NSAIDS and anti-pain drugs.

Safety Assessment of High- and Low-Molecular-Weight Hyaluronans (Profhilo®) as Derived from Worldwide Postmarketing Data

Background

At present, dermal fillers based on hyaluronic acid (HA) represent the most popular intervention of dermoesthetic medicine for the treatment of skin aging. Recent studies have shown that the combination of HA chains of different lengths and molecular weights improves tissue repair and regeneration through a synergistic mechanism. Profhilo® is a product available that has been on the market since 2015 and is based on stable, hybrid, and cooperative complexes (HyCoCos) produced by means of NAHYCO® Hybrid Technology, which is an innovative thermal process that rules out the use of any chemical reagents. The result is a filler with high biocompatibility and low viscosity that favors optimal diffusion at the tissue level to obtain the target bioremodeling of the facial contour. The objective of this review is to provide data from the overall postmarketing experience after 3 years of use and more than 40,000 patients treated with the medical device.

Methods

All spontaneous postmarketing adverse event (AE) reports received from physicians and healthcare professionals worldwide between February 9, 2015, and February 8, 2018, associated with the use of the studied medical device and sent to the IBSA global safety database were analyzed.

Results

In total, 12 adverse event reports were logged in the global database, and none were considered serious. Early-onset injection site reactions, i.e., swelling, edema, redness, ecchymosis, and erythema, were the most frequently observed. Late-onset local reactions (e.g., swelling, nodules) followed. The genesis of these reactions was considered, both by the reporting physician and IBSA, as being local reactions of hypersensitivity and/or due to inappropriate injection techniques. In no case was the product held liable for direct damage. All events resolved without any complications according to the treatment guidelines. Two late-onset reactions were collected.

Conclusions

Although underreporting of minor events cannot be ruled out, the overall number of reports is very low, thereby supporting the high tolerability and safety of the product. After 3 years of postmarketing experience, the safety profile of the studied medical device is favorable and consistent with the product information.

Bioassay-Guided Isolation of Nigracin, Responsible for the Tissue Repair Properties of Drypetes Klainei Stem Bark

Drypetes klainei Pierre ex Pax is used in Cameroon by Baka people in the wound healing process and for the treatment of burns. In a previous paper we demonstrated the ability of both water (WE) and defatted methanol (DME) extracts to accelerate scratch wound closure in fibroblast cultures, thus validating the traditional use of D. klainey stem bark in the treatment of skin lesions. In this work we carried out a bioassay-guided fractionation of the most active DME, which exhibited in vitro efficacy in accelerating wound healing process, in order to isolate and identify the compound/s responsible for the assessed biological activity. HPLC was used for the metabolite profiling of DME and fractions (analytical) and for the isolation of the bioactive compound (semi-preparative). MS analyses and NMR spectroscopy were used for identifying the isolated compound. The abilities of treatments in accelerating wound healing were studied on murine fibroblasts in terms of cell viability and cell migration (scratch wound-healing assay). The results obtained allowed to unambiguously identify the isolated bioactive compound as nigracin, a known phenolic glycoside firstly isolated and characterized from bark and leaves of Populus nigra in 1967. However, this is the first time that nigracin is identified in the Drypetes genus and that a wound healing activity is demonstrated for this molecule. Specifically, we demonstrated that nigracin significantly stimulates fibroblast growth and improves cell motility and wound closure of fibroblast monolayer in a dose-dependent manner, without any toxicity at the concentrations tested, and is still active at very low doses. This makes the molecule particularly attractive as a possible candidate for developing new therapeutic options for wound care.

Molecular Mechanisms at the Basis of Pharmaceutical Grade Triticum vulgare Extract Efficacy in Prompting Keratinocytes Healing

BACKGROUND

It has been shown that many plant- or microbial-derived oligos and polysaccharides may prompt tissue repair. Among the different extracts that have been studied, the aqueous one of Triticum vulgare (TVE) that was obtained from a whole germinated plant has been proven to have different biological properties that are useful in the process of wound healing. Nevertheless, with the long tradition of its use in pharmaceutical cream and ointments, especially in Italy, a new protocol was recently proposed (and patented) to improve the extraction process.

METHODS

In a simplified in vitro model, human keratinocyte monolayers were scratched and used to run time lapse experiments by using time lapse video microscopy (TLVM) to quantify reparation rate while considering a dose-response effect. Contemporarily, the molecular mechanisms that are involved in tissue repair were studied. In fact, key biomarkers that are involved in remodeling, such as MMP-2 and MMP-9, and in matrix structure assembly, such as collagen I, elastin, integrin αV and aquaporin 3, were evaluated with gene expression analyses (RT-PCR) and protein quantification in western blotting.

RESULTS

All TVE doses tested on the HaCat-supported cell proliferation. TVE also prompted cell migration in respect to the control, correctly modulating the timing of metalloproteases expression toward a consistent and well-assessed matrix remodeling. Furthermore, TVE treatments upregulated and positively modulated the expression of the analyzed biomarkers, thus resulting in a better remodeling of dermal tissue during healing.

CONCLUSIONS

The in vitro results on the beneficial effects of TVE on tissue elasticity and regeneration may support a better understanding of the action mechanism of TVE as active principles in pharmaceutical preparation in wound treatment.

The Effects of a Novel Series of KTTKS Analogues on Cytotoxicity and Proteolytic Activity

KTTKS is a matrikine that originates from the proteolytic hydrolysis of collagen. This peptide stimulates ECM production and types I and III collagen expression in vitro. A more stable form of KTTKS is pal-KTTKS, known as Matrixyl^® or palmitoyl pentapeptide-3. A series of novel pentapeptides, analogues of KTTKS with the general formula X-KTTKS-OH(NH₂), where X = acetyl, lipoyl, palmitoyl residues, was designed and synthesized. Their effect on amidolytic activity of urokinase, thrombin, trypsin, plasmin, t-PA, and kallikrein were tested. Cytotoxic tests on fibroblasts, as well as collagen and DNA biosynthesis tests for selected peptides, were also carried out. The test results showed that the most active plasmin inhibitors were palmitoyl peptides, whether in acid or amide form. No biological effects of lysine modification to arginine in the synthesized peptides were found. None of the synthesized peptides was not cytotoxic on fibroblasts, and three of them showed cell growth. These three compounds showed no concentration-activity relationship in the collagen and DNA biosynthesis assays.

Hybrid complexes of high and low molecular weight hyaluronan delay in vitro replicative senescence of mesenchymal stromal cells: a pilot study for future therapeutic application

Mesenchymal stem cells, a subpopulation of mesenchymal stromal cells (MSCs), are present in the stroma of several tissues. MSC in vitro cultivation for clinical treatments may greatly affect MSC properties. A primary handicap is replicative senescence that impairs MSC functions. Hyaluronan (HA) is present in the extracellular matrix that composes the stem cell niche environment and is under investigation as a key factor for in vitro stem cell growth. We evaluated the effect on MSC cultivation of HA hybrid cooperative complexes (HCC) that are obtained from high (H) and low (L) weight molecules (NAHYCO™). We compared this HCC with H-HA and L-HA. We investigated the effects of these HAs on proliferation, cell cycle, apoptosis, senescence, and differentiation following the addition of the polymer solutions in the culture media at concentrations that did not drastically modify the medium viscosity. Interestingly, 0,16% HCC significantly delayed the senescence compared with the controls. This occurred without alteration of the cell cycle, cytotoxicity, or apoptosis. HCCs also promoted adipogenic and chondrogenic differentiation. Our finding could suggest a potential functional role of HCC above the updated scientific reports of its effects and pave the way to optimization of MSC cultivation for therapeutic application.

Gamma-Irradiation-Prepared Low Molecular Weight Hyaluronic Acid Promotes Skin Wound Healing

In this study, we prepared low-molecular-weight hyaluronic acid (LMWHA) powder by γ-irradiation. The chemical and physical properties of γ-irradiated LMWHA and the in vitro cellular growth experiments with γ-irradiated LMWHA were analyzed. Then, hyaluronic acid exposed to 20 kGy of γ-irradiation was used to fabricate a carboxymethyl cellulose (CMC)/LMWHA fabric for wound dressing. Our results showed that γ-irradiated LMWHA demonstrated a significant alteration in carbon-oxygen double bonding and can be detected using nuclear magnetic resonance and ultraviolet (UV)-visible (Vis) spectra. The γ-irradiated LMWHA exhibited strain rate-dependent Newton/non-Newton fluid biphasic viscosity. The viability of L929 skin fibroblasts improved upon co-culture with γ-irradiated LMWHA. In the in vivo animal experiments, skin wounds covered with dressings prepared by γ-irradiation revealed acceleration of wound healing after two days of healing. The results suggest that γ-irradiated LMWHA could be a potential source for the promotion of skin wound healing.

Characterization of burn wound healing gel prepared from human amniotic membrane and Aloe vera extract

Background

Skin burn wound is a notable medical burden worldwide. Rapid and effective treatment of burnt skin is vital to fasten wound closure and healing properly. Amniotic graft and Aloe vera are widely used as wound managing biomaterials. Sophisticated processing, high cost, availability, and the requirement of medics for transplantation limit the application of amnion grafts. We aim to prepare a novel gel from amnion combined with the Aloe vera extract for burn wound healing which overcome the limitations of graft.

Methods

Two percent human amniotic membrane (AM), Aloe vera (AV) and AM+AV gels were prepared. In vitro cytotoxicity, biocompatibility, cell attachment, proliferation, wound healing scratch assays were performed in presence of the distinct gels. After skin irritation study, second-degree burns were induced on dorsal region of Wistar rats; and gels were applied to observe the healing potential in vivo. Besides, macroscopical measurement of wound contraction and re-epithelialization; gel treated skin was histologically investigated by Hematoxylin and eosin (H&E) staining. Finally, quantitative assessment of angiogenesis, inflammation, and epithelialization was done.

Results

The gels were tested to be non-cytotoxic to nauplii and compatible with human blood and skin cells. Media containing 500 μg/mL AM+AV gel were observed to promote HaCaT and HFF1 cells attachment and proliferation. In vitro scratch assay demonstrated that AM+AV significantly accelerated wound closure through migration of HaCaT cells. No erythema and edema were observed in skin irritation experiments confirming the applicability of the gels. AV and AM+AV groups showed significantly accelerated wound closure through re-epithelialization and wound contraction with P < 0.01. Macroscopically, AM and AM+AV treated wound recovery rates were 87 and 90% respectively with P < 0.05. Histology analysis revealed significant epitheliazation and angiogenesis in AM+AV treated rats compared to control (P < 0.05). AM+AV treated wounds had thicker regenerated epidermis, increased number of blood vessels, and greater number of proliferating keratinocytes within the epidermis.

Conclusion

We demonstrated that a gel consisting of a combination of amnion and Aloe vera extract has high efficacy as a burn wound healing product. Amniotic membrane combined with the carrier Aloe vera in gel format is easy to produce and to apply.

Evaluation of the biocompatibility and stability of allogeneic tissue-engineered cartilage in humanized mice

Articular cartilage (AC) has poor capacities of regeneration and lesions often lead to osteoarthritis. Current AC reconstruction implies autologous chondrocyte implantation which requires tissue sampling and grafting. An alternative approach would be to use scaffolds containing off-the-shelf allogeneic human articular chondrocytes (HACs). To investigate tolerance of allogeneic HACs by the human immune system, we developed a humanized mouse model implanted with allogeneic cartilage constructs generated in vitro. A prerequisite of the study was to identify a scaffold that would not provoke inflammatory reaction in host. Therefore, we first compared the response of hu-mice to two biomaterials used in regenerative medicine, collagen sponge and agarose hydrogel. Four weeks after implantation in hu-mice, acellular collagen sponges, but not acellular agarose hydrogels, showed positive staining for CD3 (T lymphocytes) and CD68 (macrophages), suggesting that collagen scaffold elicits weak inflammatory reaction. These data led us to deepen our evaluation of the biocompatibility of allogeneic tissue-engineered cartilage by using agarose as scaffold. Agarose hydrogels were combined with allogeneic HACs to reconstruct cartilage in vitro. Particular attention was paid to HLA-A2 compatibility between HACs to be grafted and immune human cells of hu-mice: HLA-A2+ or HLA-A2- HACs agarose hydrogels were cultured in the presence of a chondrogenic cocktail and implanted in HLA-A2+ hu-mice. After four weeks implantation and regardless of the HLA-A2 phenotype, chondrocytes were well-differentiated and produced cartilage matrix in agarose. In addition, no sign of T-cell or macrophage infiltration was seen in the cartilaginous constructs and no significant increase in subpopulations of T lymphocytes and monocytes was detected in peripheral blood and spleen. We show for the first time that humanized mouse represents a useful model to investigate human immune responsiveness to tissue-engineered cartilage and our data together indicate that allogeneic cartilage constructs can be suitable for cartilage engineering.

Dissecting the Dual Nature of Hyaluronan in the Tumor Microenvironment

Hyaluronan (HA) is a glycosaminoglycan with a simple structure but diverse and often opposing functions. The biological activities of this polysaccharide depend on its molecular weight and the identity of interacting receptors. HA is initially synthesized as high molecular-weight (HMW) polymers, which maintain homeostasis and restrain cell proliferation and migration in normal tissues. These HMW-HA functions are mediated by constitutively expressed receptors including CD44, LYVE-1, and STABILIN2. During normal processes such as tissue remodeling and wound healing, HMW-HA is fragmented into low molecular weight polymers (LMW-HA) by hyaluronidases and free radicals, which promote inflammation, immune cell recruitment and the epithelial cell migration. These functions are mediated by RHAMM and TLR2,4, which coordinate signaling with CD44 and other HA receptors. Tumor cells hijack the normally tightly regulated HA production/fragmentation associated with wound repair/remodeling, and these HA functions participate in driving and maintaining malignant progression. However, elevated HMW-HA production in the absence of fragmentation is linked to cancer resistance. The controlled production of HA polymer sizes and their functions are predicted to be key to dissecting the role of microenvironment in permitting or restraining the oncogenic potential of tissues. This review focuses on the dual nature of HA in cancer initiation vs. resistance, and the therapeutic potential of HA for chemo-prevention and as a target for cancer management.

Dual-plane hyaluronic acid treatment for atrophic acne scars

BACKGROUND

Acne is a common condition that affects up to 80% of all adolescents. Scarring may affect some 95% as a function of severity and delay before treatment. The pathogenesis includes enzymatic degradation of collagen fibers and subcutaneous fat.

OBJECTIVE

This study aimed to treat atrophic acne scars using the Dual-Plane injection of Hyaluronic Acid.

METHODS

A total of 12 patients with moderate-to-severe atrophic acne scars were treated with a novel NAHYCO™ based Hyaluronic Acid filler, using a dual-plane technique for two treatment sessions at a 4-week interval. Results were objectively assessed by two blinded Dermatologists and subjectively evaluated by the patients themselves.

RESULTS

A total of 8 out of the 12 patients reported moderate improvement, two indicated marked improvement and two rated minimal improvement. Dermatologists' mean global evaluation score was 2.5 ± 0.43.

LIMITATIONS

The small sample size and regional nature of a single-center study. Nevertheless, both the expert dermatologists' and the patients' evaluations of standardized high-resolution medical photographs were consistent, suggesting that this inherent bias was negligible.

CONCLUSION

The treatment led to impressive improvement in the depth of the scars, suggesting that this technique can result in safe and rapid amelioration of atrophic acne scars in only two sessions.

Synergic effect of plasma exeresis and non-cross-linked low and high molecular weight hyaluronic acid to improve neck skin laxities

BACKGROUND

Many therapeutic options are today available for neck aging, but little evidence exists about the efficacy of combining such procedures. Nonsurgical treatment of neck laxities and wrinkles is often preferred by patients, and combined strategies are nowadays emerging as the standard of care. Both plasma exeresis and hyaluronic acid (HA) injection are two emerging techniques in this setting.

AIMS

To investigate the synergic effect of plasma exeresis and non-cross-linked HA injection, in stabilized hybrid complex of low and high molecular weight, in terms of both tolerability (assessed using VAS scale of pain) and improvement of neck skin laxities, according to the GAIS score assigned by patients and clinicians.

PATIENTS/METHODS

Ten consecutive patients with signs of neck skin laxities (≥ type 3 according to the Glogau wrinkle scale) aged between 35 and 65 years were enrolled in our study. Two treatment sessions were performed. During the first session, both plasma exeresis and HA injection were performed. Patients were re-evauated after 30 days, and HA injection in the wrinkles of the neck was repeated. After 30 days from the second treatment session, a follow-up visit was performed to assess global efficacy of the two-step combined treatment and to monitor eventual long-term side effects.

RESULTS

A GAIS score of 1 or 2 was present in 90% of the treated cases, according to both patients and clinicians. Mean VAS value for pain was 2.4/10. Minor side effects such as erythema and/or edema were transient and completely resolved. No major adverse events were observed.

CONCLUSIONS

We strongly encourage the combined treatment with plasma exeresis and non-cross-linked HA injection for its promising remodeling effects in the field of neck rejuvenation.

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

High molecular weight hyaluronan (H-HA) has a pivotal role in the maintenance of normal functions of synovial fluid and structure of the articular joint, but it has been shown that its concentration is reduced in patients affected by degenerative cartilage diseases, such as osteoarthritis (OA). The aim of this study was to investigate the anti-inflammatory effects and properties of hybrid cooperative complexes based on high and low molecular weight hyaluronan (HCC) compared to H-HA on human primary cells derived by pathological joints. In addition, the rheological behavior of HCC was evaluated in order to define their potential as viscosupplement gel in degenerated joints. The experiments were performed using an in vitro model of OA based on human chondrocytes and synoviocytes isolated from degenerated joints of patients hospitalized for surgical replacement. In order to assess the anti-inflammatory effects of HCC, we evaluated NF-kB, COMP-2, IL-6, and IL-8 as specific markers at the transcriptional and/or protein level. Moreover, the proliferative properties of HCC were assessed using time lapse video microscopy. We showed that chondrocytes and synoviocytes clearly presented an altered cytokine profile compatible with a severe ongoing inflammation status. H-HA and, above all, HCC significantly reduced levels of the specific biomarkers evaluated and improved cartilage healing. The rheological profile indicated HCC suitability for intra-articular injection in joint diseases. HCC viscoelastic properties and the protective/anti-inflammatory effect on human chondrocytes and synoviocytes suggest the novel HCC-based gels as a valid support for OA management.

Protective effect of extractive and biotechnological chondroitin in insulin amyloid and advanced glycation end product-induced toxicity

Glycosaminoglycans are extracellular matrix components related to several biological functions and diseases. Chondroitin sulfate is a sulphated glycosaminoglycan synthesized as part of proteoglycan molecules. They are frequently associated with amyloid deposits and possess an active role in amyloid fibril formation. Recently, a neuroprotective effect of extracellular matrix components against amyloid toxicity and oxidative stress has been reported. Advanced glycation end products (AGEs), the end products of the glycation reaction, have been linked to amyloid-based neurodegenerative disease as associated with oxidative stress and inflammation. In this study we have analyzed the effect of chondroitin sulfate isolated from different species, in comparison with a new biotechnological unsulfated chondroitin, in the amyloid aggregation process of insulin, as well as the ability to prevent the formation of AGEs and related toxicity. The results have showed a determining role of chondroitin sulfate groups in modulating insulin amyloid aggregation. In addition, both sulfated and unsulfated chondroitins have shown protective properties against amyloid and AGEs-induced toxicity. These data are very relevant as a protective effect of these glycosaminoglycans in the AGE-induced toxicity was never observed before. Moreover, considering the issues related to the purity and safety of chondroitin from natural sources, this study suggests a new potential application for the biotechnological chondroitin.