In Vitro Effects of Low Doses of ß-Caryophyllene, Ascorbic Acid and d-Glucosamine on Human Chondrocyte Viability and Inflammation.

ß-caryophyllene (BCP), a plant-derived sesquiterpene, has been reported to have anti-inflammatory and antioxidant effects. The purpose of this study is to evaluate the effects of BCP in combination with ascorbic acid (AA) and d-glucosamine (GlcN) against macrophage-mediated inflammation on in vitro primary human chondrocytes. Changes in cell viability, intracellular ROS generation, gene expression of pro-inflammatory mediators, metalloproteinases (MMPs), collagen type II and aggrecan were analyzed in primary human chondrocytes exposed to the conditioned medium (CM) of activated U937 monocytes and subsequently treated with BCP alone or in combination with AA and GlcN. The CM-induced chondrocyte cytotoxicity was reduced by the presence of low doses of BCP alone or in combination with AA and GlcN. The exposure of cells to CM significantly increased IL-1ß, NF-κB1 and MMP-13 expression, but when BCP was added to the inflamed cells, alone or in combination with AA and GlcN, gene transcription for all these molecules was restored to near baseline values. Moreover, chondrocytes increased the expression of collagen type II and aggrecan when stimulated with AA and GlcN alone or in combination with BCP. This study showed the synergistic anti-inflammatory and antioxidative effects of BCP, AA and GlcN at low doses on human chondrocyte cultures treated with the CM of activated U937 cells. Moreover, the combination of the three molecules was able to promote the expression of collagen type II and aggrecan. All together, these data could suggest that BCP, AA and GlcN exert a chondro-protective action.

Effects of intra-articular hyaluronic acid associated to Chitlac (arty-duo®) in a rat knee osteoarthritis model.

Among conventional osteoarthritis (OA) treatments, intra-articular (i.a) viscosupplementation with hyaluronic acid (HA) is used to restore joint viscoelasticity. However, the rapid clearance and elimination of HA may limit its application. The aim of this study was to verify the improved efficacy of HA within the joint, using a lactose-modified chitosan (chitlac) as a potentially chondroprotective additive. Four weeks after induction of experimental OA by destabilization of the medial meniscus (DMM), 12-week-old Sprague Dawley male rats (n = 30), received once a week, for three weeks, i.a injections of: (i) HA associated to chitlac (ARTY-DUO®), (ii) HA; and (iii) sodium chloride (NaCl). Five animals for each group were euthanized 4 weeks after the first i.a injection, while the remaining five were euthanized 8 weeks after the first i.a injection. The restoration of physiological joint microenvironment was tested by histology, histomorphometry, immunohistochemistry, and microtomography (micro-CT). At 4 and even more at 8 weeks, histological analysis showed a significant decrease in OARSI and Mankin scores, with weaker matrix metalloproteinase (MMP)-3, MMP-13, and Galectin-3 in ARTY-DUO® group versus NaCl and HA groups. A reduction in Galectin-1 and a stronger Collagen II staining was seen in both ARTY-DUO® and HA versus NaCl. A reduction in Kreen-modified score, for synovium inflammation, was observed in the ARTY-DUO® group. Micro-CT measurements did not shown significant differences between the groups. The present results show that i.a ARTY-DUO® injections produce a significant improvement in knee articular cartilage degeneration and synovium inflammation in a rat model of DMM-induced OA. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Collagenase From Vibrio alginolyticus Cultures: Experimental Study and Clinical Perspectives.

Purpose The purpose of this study is to examine the activity of collagenase from cultures of Vibrio alginolyticus as in vitro as in biological samples and to evaluate clinical perspectives of this product about the treatment of fibroproliferative diseases like Dupuytren's contracture. Methods The experimental part of the study has been divided in 2 stages. In the first stage, the collagenase has been produced in laboratory, assessing its purity, verifying the in vitro degradation of collagen by the enzyme and measuring the size of the fragments; in the second part, an experimental injection into samples of fibrous cord typical of Dupuytren's disease has been performed in vitro. For the injection we used only collagenase, or collagenase after having subjected them to 2 types of mechanical stress or a collagenase combined with ethylenediamine tetra-acetic acid. Considering that the human samples have been treated in vitro, our institution does not require a specific informed consent. Results It appeared evident that the collagenase obtained from Vibrio alginolyticus (nonpathogenic bacterium) is highly pure (>98%) and does not contain nonspecific protease. The collagenase from Vibrio alginolyticus therefore has an excellent degradative capacity against the collagen and this activity takes on a dose- and time-dependent behavior. The collagenase from Vibrio alginolyticus does not act negatively on cell survival and collagen peptides obtained may provide a better proliferative stimulus compared to controls. Conclusions The collagenase from Vibrio alginolyticus, given its obvious ability in vitro and biological samples, could be an option in the nonsurgical treatment of Dupuytren's disease. Level of evidence Level III, therapeutic.

Hyaluronic acid induces activation of the κ-opioid receptor.

INTRODUCTION: Nociceptive pain is one of the most common types of pain that originates from an injury involving nociceptors. Approximately 60% of the knee joint innervations are classified as nociceptive. The specific biological mechanism underlying the regulation of nociceptors is relevant for the treatment of symptoms affecting the knee joint. Intra-articular administration of exogenous hyaluronic acid (HA) in patients with osteoarthritis (OA) appears to be particularly effective in reducing pain and improving patient function. METHODS: We performed an in vitro study conducted in CHO cells that expressed a panel of opioid receptors and in primary rat dorsal root ganglion (DRG) neurons to determine if HA induces the activation of opioid peptide receptors (OPr) using both aequorin and the fluorescent dye Fura-2/AM. RESULTS: Selective agonists and antagonists for each OPr expressed on CHO cells were used to test the efficacy of our in vitro model followed by stimulation with HA. The results showed that HA induces stimulatory effects on the κ receptor (KOP). These effects of HA were also confirmed in rat DRG neurons, which express endogenously the OPr. CONCLUSIONS: HA activates the KOP receptor in a concentration dependent manner, with a pEC(50) value of 7.57.

Preliminary report of in vitro reconstruction of a vascularized tendonlike structure: a novel application for adipose-derived stem cells.

INTRODUCTION: A greater supply of tendinous tissue can be obtained through tissue engineering technology with increasing application of adult stem cells. It is well known that adipose-derived stem cells (ADSCs), found in abundance in adipose tissue, have the same differentiating capacity as mesenchymal stem cells yet have the advantage of being easily isolated. In the present study, we combined the great facility of ADSCs to differentiate with the application of an external mechanical stimulus to successfully create an in vitro reconstructed tendonlike structure with a microcapillary network. MATERIALS AND METHODS: Hyalonect meshes (Fidia Advanced Biopolymers, Abano Terme, Padova, Italy) were used as scaffold. Human ADSCs were seeded onto the biomaterials, and the cell/scaffold constructs were cultured under mechanical stress for up to 15 days. Human tenocytes were used in the same conditions as control. Performance was assessed by histology, immunochemistry, ultrastructure, and biomolecular analysis. RESULTS: Adipose-derived stem cells seeded onto Hyalonect adhered and differentiated along the entire surface of the biomaterial and began to infiltrate within its structure. Subsequently, endothelial cells migrated, forming a capillary in the new extracellular matrix. CONCLUSIONS: This technique allowed for the creation of a vascularized tendon equivalent that could easily be detached from the bioreactor, thus facilitating its implant at the lesion site. These results highlight the biologic performance of biodegradable hyaluronic acid-based (HYAFF-11) scaffolds, which were shown to be suitable for deposition of the autologous extracellular matrix critical for ADSCs differentiation.

Hyaluronic acid three-dimensional scaffold for surgical revision of retracting scars: a human experimental study.

An observational study was carried out at the Plastic and Reconstructive Surgery Unit of the University of Pavia - Salvatore Maugeri Research and Care Institute, Pavia, Italy, to assess the clinical and histological long-term outcomes of autologous skin grafting of fresh surgical wounds following previous repair with a hyaluronic acid three-dimensional scaffold (Hyalomatrix®). Eleven fresh wounds from surgical release of retracted scars were enrolled in this study. A stable skin-like tissue cover was observed in all of the treated wounds in an average 1 month's time; at the end of this study, after an average of 12 months' time, all of the reconstructed areas were pliable and stable, although an average retraction rate of 51·62% was showed. Histological observation and immunohistochemical analysis displayed integration of the graft within the surrounding tissues. A regenerated dermis with an extracellular matrix rich in type I collagen and elastic fibres and with reduced type III collagen rate was observed. The epidermis and dermoepidermal junction featured a normal appearance with well-structured dermal papillae, too. Although the histological features would suggest regeneration of a skin-like tissue, with a good dermis and no signs of scarring, the clinical problem of secondary contracture is still unsolved.

Biocompatibility evaluation of ionic- and photo-crosslinked methacrylated gellan gum hydrogels: in vitro and in vivo study.

In this study, the stability and biocompatibility of methacrylated gellan gum hydrogels, obtained either by ionic- (iGG-MA) or photo-crosslinking (phGG-MA), were evaluated in vitro and in vivo. Size exclusion chromatography analysis of the methacrylated gellan gum (GG-MA) powder revealed that molecular weight is lower as compared to the non-modified material, i.e., low acyl gellan gum. The water uptake and swelling of iGG-MA and phGG-MA hydrogels were investigated in phosphate-buffered saline solution (pH 7.4). The biocompatibility of the hydrogels was firstly evaluated by producing cell-laden hydrogels. The in vitro cells encapsulation study showed that lung fibroblast cells (L929 cells) and human intervertebral disc (hIVD) cells are viable when cultured within both hydrogels, up to 21 days of culturing. The iGG-MA and phGG-MA hydrogels were also subcutaneously implanted in Lewis rats for 10 and 18 days. Tissue response to the hydrogels implantation was determined by histological analysis (haematoxylin-eosin staining). A thin fibrous capsule was observed around the implanted hydrogels. No necrosis, calcification, and acute inflammatory reaction were observed. The results presented in this study demonstrate that iGG-MA and phGG-MA hydrogels are stable in vitro and in vivo, support L929 and hIVD cells' encapsulation and viability, and were found to be well-tolerated and non-toxic in vivo.

In vitro response of osteoarthritic chondrocytes and fibroblast-like synoviocytes to a 500-730 kDa hyaluronan amide derivative.

The aim of this study was to compare the effects of native hyaluronan (HA) with that of its hexadecylamide derivative (HYADD) on proliferation of fibroblast-like synoviocytes (FLS) and chondrocytes. The production of inflammatory and anti-inflammatory cytokines was also analyzed in FLS cultures. The proliferation of osteoarthritis (OA) chondrocytes was enhanced when cells were treated with 0.5-1.5 mg mL(-1) of HA or HYADD®4-G. This effect was completely suppressed by the anti-CD44 antibody. At 0.5 to 1 mg mL(-1) , HA and HYADD®4-G did not influence the proliferation of normal or pathological FLS; however, at the higher concentration (1.5 mg mL(-1) ), HYADD®4-G did significantly inhibit cell proliferation. As to effects on inflammation, a significant increase in the expression of the IL-10 gene was observed when FLS were pretreated with tumor necrosis factor alpha and then cultured in the presence of 0.5 mg mL(-1) HYADD® 4-G or HA. The effects of HA derivatives on FLS proliferation and production of anti-inflammatory cytokines indicate that they may be of therapeutic benefit in OA. The longer residence time in the joint cavity, the increased viscoelasticity, and the anti-inflammatory potential of HYADD®4-G make it a better candidate than native HA for OA therapy.

ALMS1-deficient fibroblasts over-express extra-cellular matrix components, display cell cycle delay and are resistant to apoptosis.

Alström Syndrome (ALMS) is a rare genetic disorder (483 living cases), characterized by many clinical manifestations, including blindness, obesity, type 2 diabetes and cardiomyopathy. ALMS is caused by mutations in the ALMS1 gene, encoding for a large protein with implicated roles in ciliary function, cellular quiescence and intracellular transport. Patients with ALMS have extensive fibrosis in nearly all tissues resulting in a progressive organ failure which is often the ultimate cause of death. To focus on the role of ALMS1 mutations in the generation and maintenance of this pathological fibrosis, we performed gene expression analysis, ultrastructural characterization and functional assays in 4 dermal fibroblast cultures from ALMS patients. Using a genome-wide gene expression analysis we found alterations in genes belonging to specific categories (cell cycle, extracellular matrix (ECM) and fibrosis, cellular architecture/motility and apoptosis). ALMS fibroblasts display cytoskeleton abnormalities and migration impairment, up-regulate the expression and production of collagens and despite the increase in the cell cycle length are more resistant to apoptosis. Therefore ALMS1-deficient fibroblasts showed a constitutively activated myofibroblast phenotype even if they do not derive from a fibrotic lesion. Our results support a genetic basis for the fibrosis observed in ALMS and show that both an excessive ECM production and a failure to eliminate myofibroblasts are key mechanisms. Furthermore, our findings suggest new roles for ALMS1 in both intra- and extra-cellular events which are essential not only for the normal cellular function but also for cell-cell and ECM-cell interactions.

Temporary coverage of a forehead defect following tumor resection with a hyaluronic acid biological dressing: a case report.

 Coverage of large skin defects, especially following tumor resection and in patients who are not good candidates for procedures requiring general anesthesia, may require a staged procedure. The use of dermal substitutes to cover the defect until autologous grafting can be performed has been described. Hyaluronic acid biological dressings (HABD) also have been used for the temporary coverage of partial- to full-thickness posttraumatic or postsurgical wounds. An 82-year-old man with cardiopathy presented with an 8 cm x 4 cm ulcerated squamous cell carcinoma on his forehead. Following surgical removal under local anesthesia, the 12 cm x 8 cm defect was covered with HABD, which was removed immediately before the scheduled surgical closure (21 days later). At that time, well-vascularized granulation tissue completely covered the bone and an autologous skin graft was applied. Punch biopsy results obtained 4 weeks after surgery showed dressing remnants in the dermis and confirmed the graft was totally integrated with the surrounding tissues; there was no evidence of hypertrophy or excessive scarring. In this patient, the staged procedure provided an excellent alternative to a complex surgical procedure. Use of the biological dressing required only a weekly wound and dressing assessment and the cosmetic result was good without evidence of a recurrence at the 2-year follow-up. Studies to ascertain the efficacy and effectiveness of this dressing for the temporary coverage of soft tissue defects are needed.

Hyaluronic acid biodegradable material for reconstruction of vascular wall: a preliminary study in rats.

The objective of this preliminary study was to develop a reabsorbable vascular patch that did not require in vitro cell or biochemical preconditioning for vascular wall repair. Patches were composed only of hyaluronic acid (HA). Twenty male Wistar rats weighing 250-350 g were used. The abdominal aorta was exposed and isolated. A rectangular breach (1 mm × 5 mm) was made on vessel wall and arterial defect was repaired with HA made patch. Performance was assessed at 1, 2, 4, 8, and 16 weeks after surgery by histology and immunohistochemistry. Extracellular matrix components were evaluated by molecular biological methods. After 16 weeks, the biomaterial was almost completely degraded and replaced by a neoartery wall composed of endothelial cells, smooth muscle cells, collagen, and elastin fibers organized in layers. In conclusion, HA patches provide a provisional three-dimensional support to interact with cells for the control of their function, guiding the spatially and temporally multicellular processes of artery regeneration.

Neural potential of adipose stem cells.

In the last few years, adipose tissue, which has been largely ignored by anatomists and physicians for centuries, has found new brightness thanks to the stem cells contained within. These adipose derived stem cells (ADSC) have the same characteristics of the mesenchymal stem cells (MSC) residing in bone marrow. They have the same cell surface markers and are capable of differentiating into the same cell types, including osteoblasts, chondrocytes, myoblasts, adipocytes, and neuron-like cells. Adipose tissue is ubiquitous and uniquely expandable. Most patients possess excess fat that can be harvested, making adipose tissue the ideal large-scale source for research on clinical applications. In this review focused on the neural potential of adipose-derived stem cells. Current strategies for their isolation, differentiation, and in vitro characterization, as well as their latest in vivo applications for neurological disorders or injury repair, were discussed.

Nanoscale particle therapies for wounds and ulcers.

'Small is beautiful' - this should be the slogan of nanoscientists. Indeed, working with particles less than 100 nm in size, nanotechnology is on the verge of providing a host of new materials and approaches, revolutionizing applied medicine. The obvious potential of nanotechnology has attracted considerable investment from governments and industry hoping to drive its economic development. Several areas of medical care already benefit from the advantages that nanotechnology provides and its application in wound healing will be reviewed in this article.

A combining method to enhance the in vitro differentiation of hepatic precursor cells.

The ideal bioartificial liver should be designed to reproduce as nearly as possible in vitro the habitat that hepatic cells find in vivo. In the present work, we investigated the in vitro perfusion condition with a view to improving the hepatic differentiation of pluripotent human liver stem cells (HLSCs) from adult liver. Tissue engineering strategies based on the cocultivation of HLSCs with hepatic stellate cells (ITO) and with several combinations of medium were applied to improve viability and differentiation. A mathematical model estimated the best flow rate for perfused cultures lasting up to 7 days. Morphological and functional assays were performed. Morphological analyses confirmed that a flow of perfusion medium (assured by the bioreactor system) enabled the in vitro organization of the cells into liver clusters even in the deeper levels of the sponge. Our results showed that, when cocultured with ITO using stem cell medium, HLSCs synthesized a large amount of albumin and the MTT test confirmed an improvement in cell proliferation. In conclusion, this study shows that our in vitro cell conditions promote the formation of clusters of HLSCs and enhance the functional differentiation into a mature hepatic population.

Neural potential of a stem cell population in the adipose and cutaneous tissues.

OBJECTIVE: A significant amount of recent interest has been focused on the possibility that adult human stem cells are a realistic therapeutic alternative to embryonic stem cells. Multipotent stem cells that have characteristics reminiscent of embryonic neural crest stem cells have been isolated from several postnatal tissues, including skin, gut, dental pulp and the heart, and are potentially useful for research and therapeutic purposes. However, their neurogenic potential, including their ability to produce electrophysiologically active neurons, is largely unexplored. In the present work, we investigated this issue with regard to skin-derived precursors (SKPs) and adipose-derived stem cells (ADSc) METHODS: Adult stem cells isolated from skin and from adipose tissue derived from the same adult donor were treated with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Neurospheres obtained were first expanded and evaluated in term of proliferative ability, and then their neuronal differentiation potential was analysed. RESULTS: Adipose- and skin-derived neurospheres grew in suspension as spheres in the presence of the mitogens FGF2 and EGF. With this protocols, the spheres have been able to proliferate and to originate Schwann and glial-like cells. DISCUSSION: In summary, we have demonstrated in this work that multipotent adult precursor cell can be isolated and expanded from two accessible adult tissue sources: skin and adipose tissue. The work described in this paper provides the framework for our attempts to use SKPs or ADSc as autologous adult stem cell population for cell replacement and discovery research.

Hyaluronan-based scaffold for in vivo regeneration of the rat vena cava: Preliminary results in an animal model.

The aim of this study was to develop a prosthetic graft that could perform as a small-diameter vascular conduit for vein regeneration. The difficulty of obtaining significant long-term patency and good wall mechanical strength in vivo has been a significant obstacle in achieving small-diameter vein prostheses. Fifteen Male Wistar rats weighing 250-350 g were used. Tubular structures of hyaluronan (HYAFF-11 tubules, 2 mm diameter, and 1.5 cm length) were implanted in the vena cava of rats as temporary absorbable guides to promote regeneration of veins. Performance was assessed at 30, 60, and 90 days after surgery by histology (hematoxylin-eosin and Weighert solution) and immunohistochemistry (antibodies to von Willebrand factor and to Myosin Light-Chain Kinase). These experiments resulted in two novel findings: (1) sequential regeneration of vascular components led to complete vein wall regeneration 30 days after surgery; (2) the biomaterial used created the ideal environment for the delicate regeneration process during the critical initial phases, yet its biodegradability allowed for complete degradation of the construct 4 months after implantation, at which time, a new vein remained to connect the vein stumps. This work demonstrates the complete vena cava regeneration inside the hyaluronic acid-based prosthesis, opening new perspective of microsurgical applications, like replantation of the upper limb, elongation of vascular pedicle of free flaps, cardiovascular surgery, and pediatric microvascular surgery.

Hyaluronan benzyl ester as a scaffold for tissue engineering.

Tissue engineering is a multidisciplinary field focused on in vitro reconstruction of mammalian tissues. In order to allow a similar three-dimensional organization of in vitro cultured cells, biocompatible scaffolds are needed. This need has provided immense momentum for research on "smart scaffolds" for use in cell culture. One of the most promising materials for tissue engineering and regenerative medicine is a hyaluronan derivative: a benzyl ester of hyaluronan (HYAFF). HYAFF can be processed to obtain several types of devices such as tubes, membranes, non-woven fabrics, gauzes, and sponges. All these scaffolds are highly biocompatible. In the human body they do not elicit any adverse reactions and are resorbed by the host tissues. Human hepatocytes, dermal fibroblasts and keratinocytes, chondrocytes, Schwann cells, bone marrow derived mesenchymal stem cells and adipose tissue derived mesenchymal stem cells have been successfully cultured in these meshes. The same scaffolds, in tube meshes, has been applied for vascular tissue engineering that has emerged as a promising technology for the design of an ideal, responsive, living conduit with properties similar to that of native tissue.

Isolation method for a stem cell population with neural potential from skin and adipose tissue.

OBJECTIVE: In recent years, research on stem cells has been focused on the development of personalized cell-based therapies. Owing to their homing properties, adult human stem cells are a promising source of autologous cells to be used as therapeutic vehicles. Multiple potential sources for clinically useful stem and progenitor cells have been identified, including autologous and allogenic embryonic, fetal and adult somatic cells from neural, adipose and mesenchymal tissue. In the present report, we describe a simple protocol to obtain an enriched culture of adult stem cells organized in neurospheres from two post-natal tissues: skin and adipose tissue. METHODS: Adult stem cells isolated from skin and adipose tissue derived from the same adult donor were amplified under varying conditions related to the coating of the chamber slide and the presence of serum and/or growth factors, such as with EGF and FGF2. Neurospheres were then expanded and evaluated in terms of proliferation and gene expression. RESULTS: Adipose and skin derived neurospheres were comparable in size, quantity of cells and genes expressed. Cells from both types of tissue grew optimally without slide coating, in the presence of serum and with the combined addition of FGF2 and EGF. DISCUSSION: We describe a method for isolating and improving a population of multipotent adult precursor cells from the two most accessible adult tissue sources: skin and adipose tissue. This autologous adult stem cell population could be used for cell replacement or cell therapies.

Characteristics of repair tissue in second-look and third-look biopsies from patients treated with engineered cartilage: relationship to symptomatology and time after implantation.

INTRODUCTION: The present study established characteristics of tissue regrowth in patients suffering knee lesions treated with grafts of autologous chondrocytes grown on three-dimensional hyaluronic acid biomaterials. METHODS: This multicentred study involved a second-look arthroscopy/biopsy, 5 to 33 months post implant (n = 63). Seven patients allowed a third-look biopsy, three of which were performed 18 months post implant. Characteristics of tissues were histologically and histochemically evaluated. The remaining bone stubs were evaluated for cartilage/bone integration. For data analysis, biopsies were further divided into those obtained from postoperative symptomatic patients (n = 41) or from asymptomatic patients (n = 22). RESULTS: The percentage of hyaline regenerated tissues was significantly greater in biopsies obtained after, versus within, 18 months of implantation. Differences were also observed between symptomatic and asymptomatic patients: reparative tissues taken from symptomatic patients 18 months after grafting were mainly fibrocartilage or mixed (hyaline-fibrocartilage) tissue, while tissues taken from asymptomatic patients were hyaline cartilage in 83% of biopsies. In a small group of asymptomatic patients (n = 3), second-look and third-look biopsies taken 18 months after surgery confirmed maturation of the newly formed tissue over time. Cartilage maturation occurred from the inner regions of the graft, in contact with subchondral bone, towards the periphery of the implant. CONCLUSIONS: The study indicates that, in asymptomatic patients after chondrocyte implantation, regenerated tissue undergoes a process of maturation that in the majority of cases takes longer than 18 months for completion and leads to hyaline tissue and not fibrous cartilage. Persistence of symptoms might reflect the presence of a nonhyaline cartilage repair tissue.