Gaining insight on mitigation of rubeosis iridis by UPARANT in a mouse model associated with proliferative retinopathy.

Proliferative retinopathies (PR) lead to an increase in neovascularization and inflammation factors, at times culminating in pathologic rubeosis iridis (RI). In mice, uveal puncture combined with injection of hypoxia-conditioned media mimics RI associated with proliferative retinopathies. Here, we investigated the effects of the urokinase plasminogen activator receptor (uPAR) antagonist-UPARANT-on the angiogenic and inflammatory processes that are dysregulated in this model. In addition, the effects of UPARANT were compared with those of anti-vascular endothelial growth factor (VEGF) therapies. Administration of UPARANT promptly decreased iris vasculature, while anti-VEGF effects were slower and less pronounced. Immunoblot and qPCR analysis suggested that UPARANT acts predominantly by reducing the upregulated inflammatory and extracellular matrix degradation responses. UPARANT appears to be more effective in comparison to anti-VEGF in the treatment of RI associated with PR in the murine model, by modulating multiple uPAR-associated signaling pathways. Furthermore, UPARANT effectiveness was maintained when systemically administered, which could open to novel improved therapies for proliferative ocular diseases, particularly those associated with PR. KEY MESSAGES: • Further evidence of UPARANT effectiveness in normalizing pathological iris neovascularization. • Both systemic and local administration of UPARANT reduce iris neovascularization in a model associated with proliferative retinopathies. • In the mouse models of rubeosis iridis associated with proliferative retinopathy, UPARANT displays stronger effects when compared with anti-vascular endothelial growth factor regimen.

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.].

High-performance capillary electrophoresis to determine intact keratan sulfate and hyaluronic acid in animal origin chondroitin sulfate samples and food supplements.

Chondroitin sulfate is extracted from animal cartilaginous tissues and is commercialized as active principle against osteoarthritis. Its biological activity depends on its purity grade and could be altered by the presence of other glycosaminoglycans like keratan sulfate that could be contemporarily extracted from animal tissues or like hyaluronic acid that, instead, is added on purpose in food supplements. Although numerous methods are reported in literature for quality control analyses of chondroitin sulfate, few of them are able to detect other glycosaminoglycans. In this paper, for the first time, a new high-performance CE method was set up to quantify the chondroitin sulfate, the eventual keratan sulfate, and hyaluronic acid as intact chains: five chondroitin sulfate standards and 13 animal origin samples or food supplements from six different suppliers were analyzed. The new method was able to determine keratan sulfate similarly to a previously reported high-performance anion-exchange chromatography method, but in addition it showed the advantage to determine also the hyaluronic acid as never reported before.

Hyaluronan-based hydrogels via ether-crosslinking: Is HA molecular weight an effective means to tune gel performance?

Hyaluronan (HA)-based hydrogels obtained by crosslinking the biopolymer via ether bonds are widely used in clinical practice. There is interest in improving the design of these gels to match specific properties. Here, the possibility to tune HA-hydrogel behavior by adjusting the molecular weight distribution of the biopolymer undergoing crosslinking was investigated. Three HA samples (500, 1100 and 1600 kDa) underwent reaction with 1,4-butandioldiglycidyl-ether(BDDE) under reported conditions and the crosslinked products were characterized for chemical modification extent, swelling, rheological behavior, cohesivity, sensitivity to enzymatic degradation and effect on Human Dermal Fibroblasts (HDF). HA hydrolysis, under the highly alkaline crosslinking conditions, was also studied for the first time. The main achievements are that 1) varying HA chain length affects hydrogel behavior less than expected, due to the de-polymerization occurring alongside crosslinking, that reduces the differences in sample size 2) when differences in chain length persist notwithstanding hydrolysis, lowering HA size is a means to prepare more concentrated formulations, expected to exhibit longer duration and better cohesivity in vivo, while retaining a certain rigidity, preserving biocompatibility and slightly influencing HDF behavior in relation to CollagenI production. The study shed light on aspects concerning BDDE-HA gel manufacturing and contributed to the improvement of their design.

In Vitro Evaluation of Novel Hybrid Cooperative Complexes in a Wound Healing Model: A Step Toward Improved Bioreparation.

The effectiveness of hyaluronic acid (HA), also called as hyaluronan, and its formulations on tissue regeneration and epidermal disease is well-documented. High-molecular-weight hyaluronan (HHA) is an efficient space filler that maintains hydration, serves as a substrate for proteoglycan assembly, and is involved in wound healing. Recently, an innovative hybrid cooperative complex (HCC) of high- and low-molecular-weight hyaluronan was developed that is effective in wound healing and bioremodeling. The HCC proposed here consisted of a new formulation and contained 1.6 ± 0.1 kDa HHA and 250 ± 7 kDa LHA (low molecular weight hyaluronic acid). We investigated the performance of this HCC in a novel in vitro HaCaT (immortalized human keratinocytes)/HDF (human dermal fibroblast) co-culture model to assess its ability to repair skin tissue lesions. Compared to linear HA samples, HCC reduced the biomarkers of inflammation (Transforming Growth Factor-ß (TGF-ß), Tumor Necrosis Factor receptor-α (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8)), and accelerated the healing process. These data were confirmed by the modulation of metalloproteases (MMPs) and elastin, and were compatible with a prospectively reduced risk of scar formation. We also examined the expression of defensin-2, an antimicrobial peptide, in the presence of hyaluronan, showing a higher expression in the HCC-treated samples and suggesting a potential increase in antibacterial and immunomodulatory functions. Based on these in vitro data, the presence of HCC in creams or dressings would be expected to enhance the resolution of inflammation and accelerate the skin wound healing process.

Comparative Analyses of Pharmaceuticals or Food Supplements Containing Chondroitin Sulfate: Are Their Bioactivities Equivalent?

INTRODUCTION: Oral supplementation of chondroitin sulfate (CS) and glucosamine (GlcN), symptomatic slow-acting molecules, is recommended by European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis and Musculoskeletal Diseases (ESCEO) and other European Union (EU) guidelines for the restoration of the articular cartilage surface in patients affected by osteoarthritis (OA). They are commercialized as pharmaceutical grade products and as food supplements in combination with plant extracts hyaluronic acid, methylsulfonylmethane, and other components. Food supplements do not need to undergo the strict regulatory controls of pharmaceutical grade products; thus, composition and contaminants that could be present may not be evidenced before commercialization and these uncertainties may give rise to concerns about the bioactivity of these formulations. METHODS: In this paper 10 different food supplements (FS) from diverse European countries were analyzed in comparison with two pharmaceutical grade products (Ph) using updated analytical approaches and biochemical cell-based assays. The purity, the titer, and the origin of CS in Ph and FS samples were initially assessed in order to successively compare the biological function. Both food supplements and pharmaceutical formulations were tested in vitro, using the same final CS concentration, on primary chondrocytes and synoviocytes in terms of (i) cell viability, (ii) activation of the NF-κB-mediated inflammation pathway, (iii) cartilage oligomeric matrix protein (COMP-2), IL-6, and IL-8 production. RESULTS: All the FS presented a certain insoluble fraction; the CS and the GlcN contents were lower than the declared ones in 9/10 and 8/10 samples, respectively. All FS contained keratan sulfate (KS) at up to 50% of the total glycosaminoglycan amount declared on the label. Primary cells treated with the samples diluted to present the same CS concentration in the medium showed cytotoxicity in 7/10 FS while Ph preserved viability and reduced NF-κB, COMP-2, and secreted inflammatory cytokines. CONCLUSION: Among all samples tested, the pharmaceutical grade products demonstrated effective modulation of biomarkers counteracting the inflammation status and improving viability and the physiological condition of OA human primary chondrocyte and synoviocyte cells. In contrast to that, most FS were cytotoxic at the tested concentrations, and only 3/10 of them showed similarities to Ph sample behavior in vitro. FUNDING: This work was partially supported by PON01_1226 NUTRAFAST, MIUR Ministero dell'Università e della Ricerca Scientifica. Bioteknet financed two short-term grants for graduate technicians. The journal's Rapid Service and Open Access fees were funded by IBSA CH.

The uPAR System as a Potential Therapeutic Target in the Diseased Eye.

Dysregulation of vascular networks is characteristic of eye diseases associated with retinal cell degeneration and visual loss. Visual impairment is also the consequence of photoreceptor degeneration in inherited eye diseases with a major inflammatory component, but without angiogenic profile. Among the pathways with high impact on vascular/degenerative diseases of the eye, a central role is played by a system formed by the ligand urokinase-type plasminogen activator (uPA) and its receptor uPAR. The uPAR system, although extensively investigated in tumors, still remains a key issue in vascular diseases of the eye and even less studied in inherited retinal pathologies such as retinitis pigmantosa (RP). Its spectrum of action has been extended far beyond a classical pro-angiogenic function and has emerged as a central actor in inflammation. Preclinical studies in more prevalent eye diseases characterized by neovascular formation, as in retinopathy of prematurity, wet macular degeneration and rubeosis iridis or vasopermeability excess as in diabetic retinopathy, suggest a critical role of increased uPAR signaling indicating the potentiality of its modulation to counteract neovessel formation and microvascular dysfunction. The additional observation that the uPAR system plays a major role in RP by limiting the inflammatory cascade triggered by rod degeneration rises further questions about its role in the diseased eye.

European chondroitin sulfate and glucosamine food supplements: A systematic quality and quantity assessment compared to pharmaceuticals.

Chondroitin sulfate and glucosamine, commercialized as anti-osteoarthritis food supplements, do not undergo the strict quality controls of pharmaceuticals. In this paper a systematic multi-analytical approach was designed to analyse 25 food supplements from 8 European countries compared to 2 pharmaceuticals by using high performance anion-exchange chromatography with pulsed amperometric detection, size exclusion chromatography with triple detector array, capillary electrophoresis, mono and bi-dimensional NMR. Furthermore the biological activity was assessed on in vitro human synoviocyte and chondrocyte primary cell models. Most of the samples (over 19 out of 25) showed lower condroitin sulfate and glucosamine contents than the declared ones (up to -60.3%) while all of them showed a KS contamination (up to 47.1%). Mixed animal origin chondroitin sulfate and multiple molecular weight species were determined in more than 32% of the samples. Only 1 on 5 biologically screened samples had an effective action in vitro almost comparable to the pharmaceuticals.

Protective effect of piceatannol and bioactive stilbene derivatives against hypoxia-induced toxicity in H9c2 cardiomyocytes and structural elucidation as 5-LOX inhibitors.

Stilbenes with well-known antioxidant and antiradical properties are beneficial in different pathologies including cardiovascular diseases. The present research was performed to investigate the potential protective effect of resveratrol (1) and piceatannol (2), against hypoxia-induced oxidative stress in the H9c2 cardiomyoblast cell line, and the underlying mechanisms. Compounds 1 and 2 significantly inhibited the release of peroxynitrite and thiobarbituric acid levels at na no- or submicromolar concentrations, and this effect was more evident in piceatannol-treated cells, that significantly increased MnSOD protein level in a concentration dependent manner. Furthermore, since piceatannol, which is far less abundant in natural sources, displayed a higher bioactivity than the parent compound, we hereby report on a very fast synthesis and detailed structure-based design of a focused stilbene library. Finally, taking into account that hypoxia-induced ROS accumulation also increases expression and activity of 5-lipoxygenase (5-LOX) with production of leukotrienes, we have disclosed structural key factors crucial for 5-LOX activity. Among the synthesized analogues ( 3-7), compound 7 was the most effective in improving cardiomyocytes viability and in 5-LOX inhibition. In conclusion, modeling and experimental studies provided the basis for further optimization of stilbene analogues as multi-target inhibitors of the inflammatory and oxidative pathway.

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.

Hyaluronic acid and chondroitin sulfate, alone or in combination, efficiently counteract induced bladder cell damage and inflammation.

Interstitial cystitis and/or bladder pain syndrome (IC/BPS) are characterized by discomfort, abdominal pain, and pelvic pain, and they are often associated with chronic diseases. Pathological conditions related to IC/BPS can occur due to a defect in the integrity of the bladder lining. This defect has been ascribed to damage to the glycosaminoglycan (GAG) layer of the urinary epithelium. In addition, the incipient cascade of inflammation events might prompt extracellular matrix degradation. Several medical devices based on GAG instillation were proposed to re-establish epithelial integrity by GAGs binding to proteoglycans or interacting with structural urothelium. However, to date, only in vitro studies have investigated the GAG, hyaluronic acid (HA). In the present study, TNFα treatment was used to mimic IC/BPS-induced damage in bladder cells in an in vitro model. Highly purified fermentative HA and pharmaceutical grade bovine chondroitin sulfate (CSb), alone or in combination, were evaluated for the ability to counteract bladder cell damage. We evaluated NF-κB with western blots, and we analyzed interleukin 6 and 8 expression at the transcriptional and protein levels with quantitative RT-PCR, western blotting, and ELISA. We also evaluated the expression of an antibacterial peptide, human ß-defensin-2. We confirmed our results in a 3D bladder epithelium model. Our results demonstrated that inflammatory status was reduced in the presence of HA, CSb, and the combination of both (HA/CSb 1.6%/2% w/v). This result suggested that these GAGs might be suitable for treating IC/BPS. All the assayed biomarkers showed that HA/CSb treatment modulated cells towards a more physiological status. Finally, we compared two commercial products suggested for the IC/BPS treatments and found that the product with more Ca++, showed enhanced anti-inflammatory activity and provided superior mucoadhesivity.

UPARANT is an effective antiangiogenic agent in a mouse model of rubeosis iridis.

Puncture-induced iris neovascularization (rubeosis iridis; RI) in mice is associated with upregulation of extracellular matrix (ECM) degradation and inflammatory factors. The anti-angiogenic and anti-inflammatory efficacy of UPARANT in reducing RI was determined by noninvasive, in vivo iris vascular densitometry, and confirmed in vitro by quantitative vascular-specific immunostaining. Intravitreal administration of UPARANT successfully and rapidly reduced RI to non-induced control levels. Molecular analysis revealed that UPARANT inhibits formyl peptide receptors through a predominantly anti-inflammatory response, accompanied with a significant reduction in ECM degradation and inflammation markers. Similar results were observed with UPARANT administered systemically by subcutaneous injection. These data suggest that the tetrapeptide UPARANT is an effective anti-angiogenic agent for the treatment of RI, both by local and systemic administrations. The effectiveness of UPARANT in reducing RI in a model independent of the canonical vascular endothelial growth factor (VEGF) proposes an alternative for patients that do not respond to anti-VEGF treatments, which could improve treatment in proliferative ocular diseases. KEY MESSAGES: UPARANT is effective in the treatment of rubeosis iridis, both by local and systemic administrations. UPARANT can reduce VEGF-independent neovascularization.

The urokinase-type plasminogen activator system as drug target in retinitis pigmentosa: New pre-clinical evidence in the rd10 mouse model.

Retinitis pigmentosa (RP) is characterized by progressive loss of vision due to photoreceptor degeneration leading to secondary inflammation. The urokinase-type plasminogen activator (uPA) system contributes to retinal inflammation, but its role in RP is unknown. In the rd10 mouse model of RP, we addressed this question with the use of the peptide UPARANT designed to interact with the uPA system. UPARANT was systemically administered from post-natal day (PD) 10 to PD30 when its efficacy in RP rescue was investigated using electroretinographic recordings, Western blot and immunocytochemistry. Temporal profile of protein expression in the uPA system was also investigated. UPARANT reduced both Müller cell gliosis and up-regulated levels of inflammatory markers and exerted major anti-apoptotic effects without influencing the autophagy cascade. Rescue from retinal cell degeneration was accompanied by improved retinal function. No scotopic phototransduction was rescued in the UPARANT-treated animals as determined by the kinetic analysis of rod-mediated a-waves and confirmed by rod photoreceptor markers. In contrast, the cone photopic b-wave was recovered and its rescue was confirmed in the whole mounts using cone arrestin antibody. Investigation of the uPA system regulation over RP progression revealed extremely low levels of uPA and its receptor uPAR both of which were recovered by HIF-1α stabilization indicating that HIF-1 regulates the expression of the uPA/uPAR gene in the retina. Ameliorative effects of UPARANT were likely to occur through an inhibitory action on up-regulated activity of the αvß3 integrin/Rac1 pathway that was suggested as a novel target for the development of therapeutic approaches against RP.

Hyaluronan-based hydrogels as dermal fillers: The biophysical properties that translate into a "volumetric" effect.

Biophysical and biochemical data on hyaluronan (HA)-based dermal fillers strongly support their optimal use and design to meet specific requisites. Here, four commercially available (in Europe) HA "volumetric" fillers, among the most used in the clinical practice, have been characterized in vitro. Analyses revealed the highest amounts of water-soluble HA reported so far and provided hydrodynamic data for these soluble polymeric fractions. Volumetric gels exhibit a wide range of rigidity with most of them showing G' values around 200-300Pa. They greatly differ in cohesivity. 1mL of gel hydrates up to 2.4-3.2mL. The products completely solubilize due to Bovine Testicular Hyaluronidase (BTH)'s action, thus predicting in vivo complete resorption. For the first time, filler degradation due to reactive oxygen species (ROS) was studied by rheological measurements and a rank in stability was established. Studies using Human Dermal Fibroblasts (HDF) indicated a positive biological response to the HA networks. Further, gel capacity to prompt collagen I, elastin and aquaporin3 synthesis was demonstrated, thus suggesting a positive effect on skin elasticity and hydration, besides the physical volumetric action. The findings are the first wide assessment of features for the volumetric class of HA-fillers and include first data on their resistance to degradation by ROS and biological effects on HDF. The study represents a valuable contribution to the understanding of HA-fillers, useful to optimize their use and manufacture.

Inhibiting the urokinase-type plasminogen activator receptor system recovers STZ-induced diabetic nephropathy.

The urokinase-type plasminogen activator (uPA) receptor (uPAR) participates to the mechanisms causing renal damage in response to hyperglycaemia. The main function of uPAR in podocytes (as well as soluble uPAR -(s)uPAR- from circulation) is to regulate podocyte function through αvß3 integrin/Rac-1. We addressed the question of whether blocking the uPAR pathway with the small peptide UPARANT, which inhibits uPAR binding to the formyl peptide receptors (FPRs) can improve kidney lesions in a rat model of streptozotocin (STZ)-induced diabetes. The concentration of systemically administered UPARANT was measured in the plasma, in kidney and liver extracts and UPARANT effects on dysregulated uPAR pathway, αvß3 integrin/Rac-1 activity, renal fibrosis and kidney morphology were determined. UPARANT was found to revert STZ-induced up-regulation of uPA levels and activity, while uPAR on podocytes and (s)uPAR were unaffected. In glomeruli, UPARANT inhibited FPR2 expression suggesting that the drug may act downstream uPAR, and recovered the increased activity of the αvß3 integrin/Rac-1 pathway indicating a major role of uPAR in regulating podocyte function. At the functional level, UPARANT was shown to ameliorate: (a) the standard renal parameters, (b) the vascular permeability, (c) the renal inflammation, (d) the renal fibrosis including dysregulated plasminogen-plasmin system, extracellular matrix accumulation and glomerular fibrotic areas and (e) morphological alterations of the glomerulus including diseased filtration barrier. These results provide the first demonstration that blocking the uPAR pathway can improve diabetic kidney lesion in the STZ model, thus suggesting the uPA/uPAR system as a promising target for the development of novel uPAR-targeting approaches.

In Vitro Evaluation of Hybrid Cooperative Complexes of Hyaluronic Acid as a Potential New Ophthalmic Treatment.

PURPOSE: The purpose of this in vitro study was to assess the potential benefits of eye drops based on hybrid cooperative complexes (HCCs) obtained from high and low molecular weight hyaluronic acid (HA). METHODS: Rheological measurements were performed to adjust the HCC concentration toward optimal resistance to drainage from the ocular surface. The viscosity and mucoadhesion profiles of the optimized preparation were derived. Primary porcine corneal epithelial cells were used for biological studies. Cells were exposed to dehydration after being pretreated with the HCC solution, and protection from desiccation was evaluated using cell viability assays. Time-lapse experiments were carried out to evaluate the ability of the HCC preparation to promote corneal wound healing. The characterization studies were performed in comparison with a control HA solution representative of commercial HA-based products. RESULTS: The HCC formulation is able to deliver twice the amount of biopolymer compared with conventional products while avoiding discomfort due to excessive viscosity. The viscosity and mucoadhesion profiles allowed the authors to predict the longer in vivo retention and, therefore, an improved HCC formulation bioavailability. The new preparation also proved superior in protecting porcine corneal epithelial cells from desiccation and in hastening corneal cell wound repair in vitro. CONCLUSIONS: The results suggest that the developed formulation may be a promising topical ophthalmic medical treatment.

Innovative Biocatalysts as Tools to Detect and Inactivate Nerve Agents.

Pesticides and warfare nerve agents are frequently organophosphates (OPs) or related compounds. Their acute toxicity highlighted more than ever the need to explore applicable strategies for the sensing, decontamination and/or detoxification of these compounds. Herein, we report the use of two different thermostable enzyme families capable to detect and inactivate OPs. In particular, mutants of carboxylesterase-2 from Alicyclobacillus acidocaldarius and of phosphotriesterase-like lactonases from Sulfolobus solfataricus and Sulfolobus acidocaldarius, have been selected and assembled in an optimized format for the development of an electrochemical biosensor and a decontamination formulation, respectively. The features of the developed tools have been tested in an ad-hoc fabricated chamber, to mimic an alarming situation of exposure to a nerve agent. Choosing ethyl-paraoxon as nerve agent simulant, a limit of detection (LOD) of 0.4 nM, after 5 s of exposure time was obtained. Furthermore, an optimized enzymatic formulation was used for a fast and efficient environmental detoxification (>99%) of the nebulized nerve agent simulants in the air and on surfaces. Crucial, large-scale experiments have been possible thanks to production of grams amounts of pure (>90%) enzymes.

Positive Effects against UV-A Induced Damage and Oxidative Stress on an In Vitro Cell Model Using a Hyaluronic Acid Based Formulation Containing Amino Acids, Vitamins, and Minerals.

Ultraviolet (UV) radiations are responsible for skin photoaging inducing alteration of the molecular and cellular pathways resulting in dryness and reduction of skin elasticity. In this study, we investigated, in vitro, the antiaging and antioxidant effects of hyaluronan formulations based hydrogel. Skinkò E, an intradermic formulation composed of hyaluronic acid (HA), minerals, amino acids, and vitamins, was compared with the sole HA of the same size. For this purpose, HaCaT cells were subjected to UV-A radiations and H2O2 exposure and then treated with growth medium (CTR) combined with M-HA or Skinkò E to evaluate their protective ability against stressful conditions. Cells reparation was evaluated using a scratch in vitro model and Time-Lapse Video Microscopy. A significant protective effect for Skinkò E was shown with respect to M-HA. In addition, Skinkò E increased cell reparation. Therefore, NF-kB, SOD-2, and HO-1 were significantly reduced at the transcriptional and protein level. Interestingly, γ-H2AX and protein damage assay confirmed the protection by hyaluronans tested against oxidative stress. G6pdΔ ES cell line, highly susceptible to oxidative stress, was used as a further cellular model to assess the antioxidant effect of Skinkò E. Western blotting analyses showed that the treatment with this new formulation exerts marked antioxidant action in cells exposed to UV-A and H2O2. Thus, the protective and reparative properties of Skinkò E make it an interesting tool to treat skin aging.

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.