Hyaluronans in the treatment of osteoarthritis of the knee: evidence for disease-modifying activity

The recent progress of bone regeneration materials containing EGCG

Epigallocatechin-3-gallate (EGCG) is the most effective active ingredient in tea polyphenols and belongs to the category of catechins. EGCG has excellent antioxidant activity, anti-inflammatory, osteogenesis-promoting, and antibacterial properties, and has been widely studied in orthopedic diseases such as osteoporosis. To reach the lesion site, achieve sustained release, promote osteogenesis, regulate macrophage polarization, and improve the physical properties of materials, EGCG needs to be cross-linked or incorporated in bone regeneration materials. This article reviews the application of bone regeneration materials combined with EGCG, including natural polymer bone regeneration materials, synthetic polymer bone regeneration materials, bioceramic bone regeneration materials, metal bone regeneration materials, hydrogel bone regeneration materials and metal-EGCG networks. In addition, the fabrication methods for the regenerated scaffolds are also elaborated in the text. To sum up, it reveals the excellent development potential of materials containing EGCG and the shortcomings of current research, which will provide important reference for the future exploration of bone regeneration materials containing EGCG.

High-molecular-weight Hyaluronan Administration Inhibits Bone Resorption and Promotes Bone Formation in Young-age Osteoporosis Rats

Osteoporosis poses a significant global health concern, affecting both the elderly and young individuals, including athletes. Despite the development of numerous antiosteoporotic drugs, addressing the unique needs of young osteoporosis patients remains challenging. This study focuses on young rats subjected to ovariectomy (OVX) to explore the impact of high-molecular-weight hyaluronan (HA) on preventing OVX-induced osteoporosis. Twenty-four rats underwent OVX, while 12 underwent sham procedures (sham control group). Among the OVX rats, half received subcutaneous injections of HA (MW: 2700 kDa) at 10 mg/kg/week into their backs (OVX-HA group), whereas the other half received saline injections (0.5 ml/week) at the same site (OVX-saline group). OVX-HA group exhibited significantly higher percentages of osteoclast surface (Oc. S/BS), osteoblast surface per bone surface (Ob. S/BS), and bone volume/tissue volume (BV/TV) compared with OVX-saline group at the same age. The proportions of Ob. S/BS and BV/TV in the OVX-HA group closely resembled those of the sham control group, whereas the proportion of Oc. S/BS in the OVX-HA group was notably higher than that in the sham control group. In summary, the administration of HA significantly mitigated bone resorption and enhanced bone formation, suggesting a crucial role for HA in the treatment of young adult osteoporosis.

Pain Management Strategies in Osteoarthritis

Pain is the major symptom of osteoarthritis (OA) and is an important factor in strategies to manage this disease. However, the current standard of care does not provide satisfactory pain relief for many patients. The pathophysiology of OA is complex, and its presentation as a clinical syndrome is associated with the pathologies of multiple joint tissues. Treatment options are generally classified as pharmacologic, nonpharmacologic, surgical, and complementary and/or alternative, typically used in combination to achieve optimal results. The goals of treatment are the alleviation of symptoms and improvement in functional status. Several studies are exploring various directions for OA pain management, including tissue regeneration techniques, personalized medicine, and targeted drug therapies. The aim of the present narrative review is to extensively describe all the treatments available in the current practice, further describing the most important innovative therapies. Advancements in understanding the molecular and genetic aspects of osteoarthritis may lead to more effective and tailored treatment approaches in the future.

Safety and Efficacy of Hybrid Cooperative Complexes of Sodium Hyaluronate and Sodium Chondroitin for the Treatment of Patients with Symptomatic Knee Osteoarthritis

INTRODUCTION

Knee osteoarthritis (KOA) represents a widespread degenerative disease that causes pain and motor disability. Conservative treatments mainly focus on relieving symptoms, improving joint function, and trying to delay surgery. Safety and efficacy of hybrid cooperative complexes (2.4% sodium hyaluronate and 1.6% sodium chondroitin; HA-SC) for symptomatic KOA were investigated in a single-arm, prospective, pilot study.

METHODS

Patients with a visual analogue scale (VAS) pain score ≥ 4 and Kellgren-Lawrence Grade < 4 received a single intraarticular HA-SC injection. Patients with a VAS score change from baseline ≤ 1 received a second injection at day 30. Device-related adverse events (DR-AEs)/adverse events (AEs) were primary endpoints. Secondary endpoints included Western Ontario and McMaster Universities Osteoarthritis Index LK 3.1 (WOMAC LK 3.1), VAS, patient global assessment of disease status (PtGA), and patient proportion needing a second injection.

RESULTS

Of 83 patients with KOA (Kellgren-Lawrence Grade, 2-3), 34.9% had DR-AEs at day 7. No serious DR-AEs/AEs were reported. A significant (P < 0.0001) reduction over time in VAS pain score plus WOMAC pain, stiffness, physical function limitation, and total scores was reported. Median PtGA scores indicated a 'slight improvement' at most follow-up visits. Only 18.1% of patients required a second injection.

CONCLUSIONS

A single intraarticular HA-SC injection was safe, well-tolerated, and did not lead to major deterioration in terms of reducing knee pain, stiffness, and physical function limitation in patients with symptomatic KOA.

Effects of Diclofenac Etalhyaluronate (SI-613/ONO-5704) on Cartilage Degeneration in Arthritic Rats and Inflammatory Cytokine-Stimulated Human Chondrocytes

OBJECTIVE

Cartilage degeneration is a key feature of osteoarthritis (OA) and rheumatoid arthritis and is thought to negatively impact patients' quality of life. Diclofenac etalhyaluronate (DEH, SI-613/ONO-5704) is a hyaluronic acid (HA) derivative chemically bound to diclofenac (DF) that has been reported to improve OA symptoms; however, its effect on cartilage degeneration remains unknown. In the present study, we investigated the chondroprotective effect of DEH in rats with collagen-induced arthritis and interleukin-1β-stimulated human chondrocytes.

DESIGN

Rats with collagen-induced arthritis were administered DEH and HA intra-articularly, and DF orally. Knee joint swelling, histological scores of articular cartilage, and inflammatory (Il1b) and catabolic (Mmp3 and Mmp13) gene expression in the synovial tissue and cartilage were evaluated. In vitro direct effects of DEH on matrix metalloproteinase (MMP)-3 and MMP-13 expression were examined in interleukin-1β-stimulated human chondrocytes.

RESULTS

In a rat model of collagen-induced arthritis, a single intra-articular dose of DEH inhibited knee joint inflammation and cartilage degeneration. Daily oral administration of DF had similar effects. Conversely, HA administered as a single intra-articular dose had no effect. Only DEH inhibited Mmp3 gene expression in the cartilage, whereas DEH and DF inhibited Mmp3 and Mmp13 mRNA expression in the synovial tissue. In interleukin-1β-stimulated human chondrocytes, DEH and HA inhibited MMP-3 and MMP-13 production, whereas DF had no effect.

CONCLUSIONS

In this study, we demonstrated the chondroprotective effect of DEH in rats with collagen-induced arthritis and in interleukin-1β-stimulated human chondrocytes. Thus, DEH may suppress cartilage degeneration in patients with musculoskeletal diseases, such as OA.

HYBID in osteoarthritis: Potential target for disease progression

HYBID is a new hyaluronan-degrading enzyme and exists in various cells of the human body. Recently, HYBID was found to over-express in the osteoarthritic chondrocytes and fibroblast-like synoviocytes. According to these researches, high level of HYBID is significantly correlated with cartilage degeneration in joints and hyaluronic acid degradation in synovial fluid. In addition, HYBID can affect inflammatory cytokine secretion, cartilage and synovium fibrosis, synovial hyperplasia via multiple signaling pathways, thereby exacerbating osteoarthritis. Based on the existing research of HYBID in osteoarthritis, HYBID can break the metabolic balance of HA in joints through the degradation ability independent of HYALs/CD44 system and furthermore affect cartilage structure and mechanotransduction of chondrocytes. In particular, in addition to HYBID itself being able to trigger some signaling pathways, we believe that low-molecular-weight hyaluronan produced by excess degradation can also stimulate some disease-promoting signaling pathways by replacing high-molecular-weight hyaluronan in joints. The specific role of HYBID in osteoarthritis is gradually revealed, and the discovery of HYBID raises the new way to treat osteoarthritis. In this review, the expression and basic functions of HYBID in joints were summarized, and reveal potential role of HYBID as a key target in treatment for osteoarthritis.

Hyaluronic Acid in Rheumatology

Hyaluronic acid (HA), also known as hyaluronan, is an anionic glycosaminoglycan widely distributed throughout various tissues of the human body. It stands out from other glycosaminoglycans as it lacks sulfation and can attain considerable size: the average human synovial HA molecule weighs about 7 million Dalton (Da), equivalent to roughly 20,000 disaccharide monomers; although some sources report a lower range of 3-4 million Da. In recent years, HA has garnered significant attention in the field of rheumatology due to its involvement in joint lubrication, cartilage maintenance, and modulation of inflammatory and/or immune responses. This review aims to provide a comprehensive overview of HA's involvement in rheumatology, covering its physiology, pharmacology, therapeutic applications, and potential future directions for enhancing patient outcomes. Nevertheless, the use of HA therapy in rheumatology remains controversial with conflicting evidence regarding its efficacy and safety. In conclusion, HA represents a promising therapeutic option to improve joint function and alleviate inflammation and pain.

A single centre, open label, pilot study evaluating the effect of intra-articular hyaluronic acid injection on pain and functionality when injected into the ankle (tibio-talar and sub-talar) joint in patients with haemophilic arthropathy

AIMS

Ankle arthropathy commonly affects persons with haemophilia (PWH). Joint damage causes loss of movement, pain and reduced function. Current treatments are limited. Viscosupplementation has been used to treat other patient groups with joint damage. Viscosupplements serve to augment or act as a substitute for synovial fluid and may ameliorate the effects of cartilage loss by cushioning joints and reducing pain. This study evaluated intra-articular Ostenil Plus™ (HA) for ankle arthropathy in PWH. Reduction in pain was the primary outcome.

METHODS

A single centre open label pilot study. PWH and significant ankle arthropathy, according to MRI scores, were recruited. Participants received intra-articular HA injections at baseline and 6 months. Follow up assessments were completed three-monthly for 1 year. Pain was assessed by the Visual Analogue Scale (VAS). Participant perceptions of overall changes to pain, function and quality of life were sought.

RESULTS

Twenty-four participants were recruited, three withdrew. Twenty-six joints were injected. Twenty participants had severe haemophilia. Mean age 35 years. Participants reported significant reduction in pain over the study. VAS baseline: 5.62; 6 month 3.92; 12-month 3.42, P < .0001. Joint function improved together with ankle HJHS. No change was seen for EQ-5D-5L. Sixteen participants reported reductions in ankle pain and stiffness and greater confidence in undertaking physical activities. No significant adverse reactions were reported.

CONCLUSION

Ostenil Plus™ treatment improves pain, function and patient perception of functional ability in PWH and ankle arthropathy. This study supports the use of HA as a safe treatment in PWH.

Efficacy of a Novel Intra-Articular Administration of Platelet-Rich Plasma One-Week Prior to Hyaluronic Acid versus Platelet-Rich Plasma Alone in Knee Osteoarthritis: A Prospective, Randomized, Double-Blind, Controlled Trial

Recent studies have suggested that the combined injection of platelet-rich plasma (PRP) and hyaluronic acid (HA) may have additive benefits for knee osteoarthritis over PRP alone, but there is insufficient evidence to support this combined injection. Moreover, the simultaneous injection of PRP and HA may offset the combined effect. Hence, the aim of this prospective, randomized, double-blind study was to assess their combined efficacy with a novel injection protocol. Forty-six study subjects with unilateral knee osteoarthritis were randomized to receive either a single-dose injection of HA (intervention group) or normal saline (control group) 1 week after a single-dose injection of leukocyte-poor PRP. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and static balance and the risk of falls measured by Biodex Balance System were, respectively, the primary and secondary outcome measures. Evaluations were performed at baseline, 1 month, 3 months, 6 months, and 12 months post-injection. The intervention group exhibited significant declines in WOMAC pain, stiffness, and total scores, as well as static balance, compared to the control group (p < 0.05). These randomized double-blind control trials, with novel protocol of intra-articular injection of PRP 1-week prior to HA, provide greater symptom relief and improve static balance compared to PRP alone in patients with knee osteoarthritis.

Management of osteoarthritis: From drug molecules to nano/micromedicines

With the change in lifestyle and aging of the population, osteoarthritis (OA) is emerging as a major medical burden globally. OA is a chronic inflammatory and degenerative disease initially manifesting with joint pain and eventually leading to permanent disability. To date, there are no drugs available for the definitive treatment of osteoarthritis and most therapies have been palliative in nature by alleviating symptoms rather than curing the disease. This coupled with the vague understanding of the early symptoms and methods of diagnosis so that the disease continues as a global problem and calls for concerted research efforts. A cascade of events regulates the onset and progression of osteoarthritis starting with the production of proinflammatory cytokines, including interleukin (IL)‐1β, IL‐6, tumor necrosis factor (TNF)‐α; catabolic enzymes, such as matrix metalloproteinases (MMPs)‐1, ‐3, and ‐13, culminating into cartilage breakdown, loss of lubrication, pain, and inability to load the joint. Although intra‐articular injections of small and macromolecules are often prescribed to alleviate symptoms, low residence times within the synovial cavity severely impair their efficacy. This review will briefly describe the factors dictating the onset and progression of the disease, present the current clinically approved methods for its treatment and diagnosis, and finally elaborate on the main challenges and opportunities for the application of nano/micromedicines in the treatment of osteoarthritis. Thus, future treatment regimens will benefit from simultaneous consideration of the mechanobiological, the inflammatory, and tissue degradation aspects of the disease.

This article is categorized under:

Nanotechnology Approaches to Biology > Nanoscale Systems in Biology

Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement

Marine Polysaccharides in Tailor- Made Drug Delivery

Abstract:

Marine sources have attracted much interest as an emerging source of biomaterials in drug delivery applications. Amongst all other marine biopolymers, polysaccharides have been the mostly investigated class of biomaterials. The low cytotoxic behavior, in combination with the newly explored health benefits of marine polysaccharides has made it one of the prime research areas in the pharmaceutical and biomedical fields. In this review, we focused on all available marine polysaccharides, including their classification based on biological sources. The applications of several marine polysaccharides in recent years for tissue-specific novel drug delivery including gastrointestinal, brain tissue, transdermal, ocular, liver, and lung have also been discussed here. The abundant availability in nature, cost-effective extraction, and purification process along with a favorable biodegradable profile will encourage researchers to continue investigating marine polysaccharides for exploring newer applications in targeting specific delivery of therapeutics.

Safety and synovial inflammatory response after intra-articular injection of botulinum toxin type A in healthy horses

Botulinum toxin type A (BoNT-A) is a promising alternative for patients suffering from chronic joint pain. The aim of this study was to investigate whether a single injection of BoNT-A would produce adverse effects on clinical parameters and synovial parameters as well as lameness. One randomly selected radiocarpal joint was treated with 50 U of BoNT-A in eight horses, and the contralateral joint received saline solution. All horses received injections at day 0 and were re-evaluated twice daily for seven days for heart rate (HR), respiratory rate (RR), rectal temperature (RT), mucous membrane color, capillary refill time, intestinal motility, appetite, water intake, defecation, urination, and attitude. At these same time points, joint pain and circumference were assessed. Objective lameness evaluations were performed once daily for seven days and synovial fluid samples were collected at baseline, post-injection hour (PIH) 24 and PIH 168 and evaluated for synovial fluid parameters. HR and RT remained clinically unaltered, despite oscillations over time (p=0.001). The remaining clinical parameters were unaltered by treatment or time (p>0.05). Joint pain was not elicited by flexion and palpation in both limbs as well as carpal circumference was not altered (p=0.88). Lameness was observed only on saline limbs. Cellular parameters evaluated in synovial fluid samples from both carpi had significantly increased from baseline to PIH 24, decreasing at PIH 168 (p<0.05). It was concluded that the injection of 50 U BoNT-A is suggested to be a safe therapy for intra-articular use in horses and must be verified by further investigation.

The efficacy of intra-articular injections in the treatment of knee osteoarthritis: A network meta-analysis of randomized controlled trials

PURPOSE

Osteoarthritis (OA) is a debilitating joint disease characterized by progressive loss of articular cartilage. Intra-articular injections are a mainstay of nonoperative treatment, however, there is controversy as to the optimal injectable for these patients. The purpose of the current study is to perform a network meta-analysis of the randomized control trials in the literature to ascertain whether there is a superior injectable nonoperative treatment for knee OA.

METHODS

The literature search was conducted based on the PRISMA guidelines. Randomized control trials (RCTs) evaluating intra-articular injectables in osteoarthritic knees were included. Data was extracted and Visual Analogue Scale (VAS) scores and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores, where available were analyzed at 1, 3, 6 and 12 months. Clinical outcomes were compared using a frequentist approach to network meta-analysis, with statistical analysis performed using R. The treatment options were ranked using the P-Score.

RESULTS

Seventy-nine RCTs with 8761 patients were included in this review. Intra-articular injectables evaluated included autologous conditioned serum (ACS), bone marrow aspirate concentrate (BMAC), botulinum toxin, corticosteroids (CS), hyaluronic acid (HA), mesenchymal stem cells (MSC), ozone, saline placebo, platelet-rich plasma (PRP), plasma rich in growth factor (PRGF), and stromal vascular fraction (SVF). At 4-6 weeks and 3 months of follow-up, the treatment with the highest P-Score for WOMAC score was high molecular weight (HMW) HA + CS [P-Score = 0.9500 and 8503, respectively]. At 6-months follow-up, the treatment with the highest P-Score for WOMAC score was PRP [P-Score = 0.7676]. At all post-injection time points, the treatment with the highest P-Score for VAS score [P-Score Range = 0.8631-9927] and Womac score at 12 Months [P-Score = 0.9044] was SVF.

CONCLUSIONS

The current evidence shows that SVF injections result in the greatest improvement in pain and functional outcomes in patients with knee OA at up to 1 year of follow-up.

Drug delivery carriers with therapeutic functions

Design of micro- or nanocarriers for drug delivery has primarily been focused on properties such as hydrophobicity, biodegradability, size, shape, surface charge, and toxicity, so that they can achieve optimal delivery with respect to drug loading, release kinetics, biodistribution, cellular uptake, and biocompatibility. Incorporation of stimulus-sensitive moieties into the carriers would lead to "smart" delivery systems. A further evolution would be to endow the carrier with a therapeutic function such that it no longer serves as a mere passive entity to release the drug at the target tissue but can be viewed as a therapeutic agent in itself. In this review, we will discuss recent and ongoing efforts over the past decade to design therapeutic drug carriers that confer a biological benefit, including ROS scavenging or generating, pro- or anti-inflammatory, and immuno-evasive properties, to enhance the overall therapeutic efficacy of the delivery systems.

Hyaluronan as a Prominent Biomolecule with Numerous Applications in Medicine

Hyaluronan (HA) is a natural glycosaminoglycan present in many tissues of all vertebrates. HA has various biological functions, which are dependent on its molar mass. High-molar-mass HA has anti-angiogenic, immunosuppressive and anti-inflammatory properties, while low-molar-mass HA has opposite effects. HA has also antioxidative properties, however on the other hand it can be readily degraded by reactive oxygen species. For many years it has been used in treatment of osteoarthritis, cosmetics and in ophthalmology. In the last years there has been a growing interest of HA to also be applied in other fields of medicine such as skin wound healing, tissue engineering, dentistry and gene delivery. In this review we summarize information on modes of HA administration, properties and effects of HA in various fields of medicine including recent progress in the investigation of HA.

Safety and efficacy of single CHAP Hyaluronan injection versus three injections of linear Hyaluronan in pain relief for knee osteoarthritis: a prospective, 52-week follow-up, randomized, evaluator-blinded study

Background

The hyaluronic acid (HA) injections are widely used in knee osteoarthritis (OA) patients. We conducted the study comparing the efficacy and safety of single injection of Crosslinked Hyaluronic Acid Platform Hyaluronan (CHAP-HA) with 3-injection of linear hyaluronan in knee OA patients.

Methods

This was a randomized two-arms, evaluator-blinded, controlled, single-center study. Participants with knee OA received single CHAP-HA or three-injection of linear-HA. The 140 patients aged 35–85 years with radiographically confirmed knee OA were enrolled. At week 4, 12, 26, 39, and 52, visual analog scale (VAS) pain score, Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index, timed up and go (TUG) and subject’s adverse events (AE) of these 2 groups were recorded. Primary outcome of the differences of VAS pain score at week 26 between groups was analyzed with analysis of covariance (ANCOVA). At week 52, those who met the inclusion criteria could receive a CHAP-HA injection and being followed-up for the adverse events for 4 weeks.

Results

The trial was conducted from September 2015 to April 2017. A total 140 subjects were available for analysis (71 in the CHAP-HA group and 69 in the linear-HA group). At 26th week, there were significant more improvements in VAS pain scores in CHAP-HA compared with linear-HA. Both CHAP-HA and linear-HA showed significant improvements in the VAS pain score at week 26 compared with the baseline, and the occurrence of adverse events during the study period showed no between-group difference. In subjects with KL = 2, both groups showed significant improvements in VAS pain scores within 26 weeks. In patients with KL = 3, only CHAP-HA group showed significant improvement in VAS pain from 4 to 39 weeks. No unexpected or severe AEs were reported.

Conclusions

A single injection of CHAP-HA may be safe and more effective for 26 weeks in patients with knee OA by comparing to linear-HA; moreover, the pain relief effect of CHAP-HA may remain until 52 weeks. For patients with more severe OA, CHAP-HA was demonstrated to be more preferable to relieve OA pain. Furthermore, repeat treatment of CHAP-HA or using CHAP-HA after a three-injection HA was proved to be safe.

Trial registration

ClinicalTrials.gov: NCT03643588. Date: August 23, 2018 (retrospectively registered).

Level of Evidence: Therapeutic Level I.

Clinical effectiveness and safety of intra-articular injection of HYALGO in the management of knee osteoarthritis symptoms: A multicenter prospective study

BACKGROUND

The reduced concentration of hyaluronic acid in the synovial fluid, leading to impairment of joint function and painful symptomatology during knee osteoarthritis (OA), can be restored by using injectable formulations of hyaluronic acid (HA) and chondroitin sulfate (CS), variable for relative composition, HA/CS molecular modifications, and injection protocols. The present study aims to assess the safety and performance of the intra-articular (IA) viscosupplementing agent HYALGO, a formulation combining 40 mg/mL HA (>1700 kDa) and 40 mg/mL CS, in the treatment of patients suffering from knee OA.

METHODS

74 patients affected by knee lesions classified as grade II and III according to Kellgren and Lawrence classification were prospectively recruited and treated with three HYALGO injections (2 mL) given one week apart. Visual analogue scale (VAS) pain changes were monitored at each injection and over-time at 6, 14, and 26 weeks of follow-up. Secondary endpoints were: Western Ontario McMaster University Osteoarthritis index (WOMAC), Patient's Global Assessment (PGA) score, Clinical Observer Global Assessment (COGA) score, Outcome Measures in Rheumatology Committee (OMERACT) and Osteoarthritis Research Society International (OARSI) responders rates. Patients were also assessed for changes in their ultrasound joint scores according to the criteria of the OMERACT US Task Force Group.

RESULTS

Pain reduction was statistically significant starting from the first IA injection. Mean pain reduction from baseline to week 26 was -90.6%. At 26 weeks, WOMAC Pain was reduced by -62.7%, WOMAC Stiffness by -47.2%, WOMAC Physical Function by -54.1%; Total WOMAC by -53.8%. The VAS PGA change from baseline was -48.0 [mm] and VAS COGA -41.0 [mm]. Responders at week 26 were 78.4%. Ultrasound parameters (joint effusion, synovial thickness, and popliteal cysts) improved or remained stable from baseline to week 6.

CONCLUSIONS

Three injections of HYALGO were safe and effective to manage symptomatic knee OA, with a beneficial effect that increased progressively over time, peaking 6 months after injection.

The role of viscosupplementation in patellar chondropathy

Patellar chondropathy has a high incidence in the general population, being more common in patients younger than 50 years, female and recreational athletes, and overweight and obese patients. The most common complaints are pain, limited mobility, crepitus, difficulty climbing and descending stairs, and joint instability, usually showing unsatisfactory results with anti-inflammatory, physiotherapy, rehabilitation, and many other conservative treatment methods. The presumed hyaluronic acid (HA) disease-modifying activity may include effects on cartilage degradation, endogenous HA synthesis, synoviocyte and chondrocyte function, and other cellular inflammatory processes. Currently, HA is widely used as a safe and effective conservative treatment for osteoarthritis in the knee and other joints. HA improves the physiological environment in an osteoarthritic joint and the shock absorption and lubrication properties of the osteoarthritic synovial fluid, thus restoring the protective viscoelasticity of the synovial HA, reducing the pain, and improving the mobility. The complete mechanism of HA in the joint is not fully understood, but a wide range of actions in the joint is recognized. Its anti-inflammatory, analgesic, and chondroprotective action is related to the modulation of the intra- and extracellular inflammation cascade. HA has been shown to be safe and effective in the treatment of pain related to patellar chondropathy.

Immunomodulatory biomaterials and their application in therapies for chronic inflammation-related diseases

The degree of tissue injuries such as the level of scarring or organ dysfunction, and the immune response against them primarily determine the outcome and speed of healing process. The successful regeneration of functional tissues requires proper modulation of inflammation-producing immune cells and bioactive factors existing in the damaged microenvironment. In the tissue repair and regeneration processes, different types of biomaterials are implanted either alone or by combined with other bioactive factors, which will interact with the immune systems including immune cells, cytokines and chemokines etc. to achieve different results highly depending on this interplay. In this review article, the influences of different types of biomaterials such as nanoparticles, hydrogels and scaffolds on the immune cells and the modification of immune-responsive factors such as reactive oxygen species (ROS), cytokines, chemokines, enzymes, and metalloproteinases in tissue microenvironment are summarized. In addition, the recent advances of immune-responsive biomaterials in therapy of inflammation-associated diseases such as myocardial infarction, spinal cord injury, osteoarthritis, inflammatory bowel disease and diabetic ulcer are discussed.

Efficacy and safety of viscosupplementation with hyaluronic acid for hip osteoarthritis: results from a cross-sectional study with a minimum follow-up of 4 years

Background and aim of the work:

Osteoarthritis is the most common cause of disability in elderly. Hip osteoarthritis is the second most frequent form affecting a large joint and the social and economic impact on society of its related disability is expected to increase. The purpose of this study was to verify the efficacy and safety of ultrasound-guided viscosupplementation with high weight hyaluronic acid in hip osteoarthritis.

Methods:

183 patients with painful hip OA (Kellgren-Lawrence 1-2-3) were treated from January 2014 to December 2016 with viscosupplementation. Patients were evaluated before injection (T0) and after 1,2,3,4 (T1-T2-T3-T4) years through the VAS scale and Harris Hip Score (HHS). Patients who underwent to subsequent injections were followed and assessed. Subjects who underwent prosthesis were analyzed for a minimum of 6 months in order to detect any early postoperative complication.

Results:

The mean improvement of HHS and VAS between T0 and T1 was statistically significant. Patients who underwent subsequent injections showed a higher improvement even if statistical significance was not observed. Results showed that patients with grade 2 of osteoarthritis had the higher change in the scores. No adverse effects were registered. No early complications were reported in those patients who needed prosthesis.

Discussion and Conclusions:

Results observed confirm that ultrasound-guided viscosupplementation with high weight hyaluronic acid could be a possibility in the treatment of hip osteoarthritis, especially in patients with Kellgren-Lawrence grade 2 of disease. Subsequent injections are not characterized by similar positive effects. Outcomes of prosthetic surgery are not influenced by viscosupplementation.

Single-Dose Intra-Articular Administration of a Hybrid Cooperative Complex of Sodium Hyaluronate and Sodium Chondroitin in the Treatment of Symptomatic Hip Osteoarthritis: A Single-Arm, Open-Label, Pilot Study

Introduction

Intra-articular (i.a.) hyaluronic acid is an accepted conservative therapy for knee osteoarthritis (OA). This study evaluated the safety and efficacy of a single i.a. injection of an innovative formulation of sodium hyaluronate 2.4% plus sodium chondroitin non-sulphated 1.6% of biotechnological origin (HA-SC) for the treatment of patients with radiographically confirmed symptomatic hip OA and moderate-to-severe pain.

Methods

In this prospective, multicenter, open-label, pilot study, HA-SC was administered using a standard ultrasound-guided procedure. Adverse events, global/local evaluation of tolerability, and use of rescue analgesics were recorded. Efficacy endpoints included visual analogue scale (VAS) measurement of hip pain, changes in Lequesne’s algofunctional Index, and assessment of global status.

Results

Treatment was well tolerated; adverse device events of moderate-to-severe intensity, most commonly, injection site pain/localized arthralgia occurred in 20.8% of subjects. Global evaluation of tolerability was rated as excellent or good (75.0%), fair (16.7%), and poor (8.3%) by subjects and 77.1, 14.6, and 8.3%, respectively, by investigators. There was a rapid and significant decrease in hip pain after a single injection; VAS pain score decreased from a mean of 67.5 mm at baseline to 29.3 mm by day 7, with the effects sustained during 6 months of follow-up (P < 0.0001). There were significant improvements in Lequesne’s Index for hip OA total scores at all time points during follow-up (P < 0.0001). The majority of subjects reported ‘Very much improved’ or ‘Slightly improved’ global improvement at any time point. Use of rescue paracetamol was generally low.

Conclusions

A single i.a. injection of an innovative HA-SC formulation was well tolerated, safe, and effective in the treatment of symptomatic hip OA.

Hyaluronic Acid Loaded with Cerium Oxide Nanoparticles as Antioxidant in Hydrogen Peroxide Induced Chondrocytes Injury: An In Vitro Osteoarthritis Model

Osteoarthritis (OA) is the most common joint disease type and is accompanied by varying degrees of functional limitation. Both hyaluronic acid (HA) joint injections and pain relievers are efficient treatments for early-stage osteoarthritis. However, for the decomposition by hyaluronidase and free radicals in the knee joint, HA injection treatment has limited effect time. The cerium oxide nanoparticles (CeO₂) is a long time free radical scavenger. CeO₂ combined with HA expected, may extend the HA decomposition time and have a positive effect on osteoarthritis therapy. In this study, CeO₂ was successfully synthesized using the hydrothermal method with a particle size of about 120 nm, which possessed excellent dispersibility in the culture medium. The in vitro OA model was established by cell treated with H₂O₂ for 30 min. Our study found that the inhibition of chondrocyte proliferation dose-dependently increased with H₂O₂ concentration but was significantly decreased by supplementation of cerium oxide nanoparticles. COL2a1 and ACAN gene expression in chondrocytes was significantly decreased after H₂O₂ treatment; however, the tendency was changed after cerium oxide nanoparticles treatment, which suggested that damaged chondrocytes were protected against oxidative stress. These findings suggest that cerium oxide nanoparticles are potential therapeutic applications in the early stage of OA.

Uncommon Structures of Oppositely Charged Hyaluronan/Surfactant Assemblies under Physiological Conditions

Self-assembled aggregates formed by semidilute polyanion hyaluronan (hyaluronic acid, HA) and an oppositely charged surfactant tetradecyltrimethylammonium bromide (TTAB) in an aqueous phosphate-buffered saline (PBS) solution have been studied via light scattering (LS), small-angle neutron scattering (SANS), and cryogenic transmission electron microscopy (cryo-TEM). The addition of 0-20 mM TTAB to a 27.7 mM (monomer, 1 wt %) HA solution (597 kDa) in PBS buffer leads to soluble complexes until phase separation occurs near charge equilibrium (>20 mM TTAB). While the viscosity remains rather constant, already small amounts of added TTAB lead to the formation of large globular superstructures, which are built in a hierarchical fashion from a locally threadlike structural arrangement of TTA micelles along the stiff HA chains, within the little changed HA network. These globular domains have radii of 60-100 nm and contain 500-700 TTA micelles, which means that they are very "fluffy" and composed of about 99% water. They do not grow in size or number upon further TTAB addition, but, instead, the additional TTA micelles form further threadlike complexes outside of the big globular domains. Such a type of polyelectrolyte-surfactant complexes (PESCs) has not been described before and has to be attributed to the particular properties of HA, which are high stiffness and relatively weak interactions with oppositely charged micelles due to having the charged carboxylic group close to the polysaccharide backbone. These findings demonstrate that the HA network structure in solution basically remains unaffected by complexation with an oppositely charged surfactant, explaining the unchanged rheological behavior and the formation of a unique PESC local "coacervate" structure within the HA hydrogel network.

The use of cellular matrix in symptomatic knee osteoarthritis

Knee osteoarthritis is a degenerative "wear and tear" disorder affecting mainly population over 50 years old. It can also present in younger people, especially after an injury or as a part of other diseases. While many therapeutic options exist for knee osteoarthritis, none of them has the potential to cure this condition. Cellular Matrix represents a combination of natural non-crosslinked hyaluronic acid (HA), thixotropic cell separation gel, and sodium citrate anticoagulant solution. A combination of Cellular Matrix with autologous platelet-rich plasma (A-PRP) is a novel therapeutic approach to the management of knee osteoarthritis. It is assumed that the active components HA and PRP have a synergistic effect contributing to a better therapeutic outcome in patients with knee osteoarthritis. Physiotherapy could provide an additional benefit. This is a retrospective pilot study assessing the potential benefit of Cellular Matrix and A-PRP combined with physiotherapy in the management of chronic knee osteoarthritis. Twenty-five patients were enrolled in the study and injected with three doses of Cellular Matrix combined with A-PRP with a time span of 2 weeks between each injection. All patients received standardized physiotherapy. The results showed that 68% of patients achieved more than 50% improvement in pain, stiffness, and function of the knee joints. There were no adverse reactions. This retrospective pilot study confirmed the positive effect of PRP and HA combination in the management of mild and moderate knee osteoarthritis. These preliminary results need to be verified in randomized control trials.

[Hyaluronate acid for treatment of chondromalacia patellae: a 52-week follow-up study]

OBJECTIVE

To assess the therapeutic effect of hyaluronate acid (HA) injection through the subpatellar route for treatment of chondromalacia patellae (CP).

METHODS

Eighty-eight patients with the diagnosis of CP were enrolled in this prospective study, including 38 with early CP (CP group) and 50 with advanced CP (patellofemoral arthritis group) diagnosed based on image presentations. All the patients received intra-articular HA injections through a subpatellar route once a week for 5 consecutive weeks. The primary outcome measures included WOMAC index scores and Lequesne scores before and at 4, 12, 26 and 52 weeks after the injections. The secondary outcome measures included the 30-m walking time and stair ascending and descending time (one floor) before and at 1, 2, 3, and 4 weeks after the injections.

RESULTS

In both groups the patients showed significantly decreased WOMAC scores and Lequesne scores at 4, 12, 26 and 52 weeks after HA injections as compared with the baseline scores (all P < 0.01). No significant difference was found between the two groups in WOMAC scores and Lequesne scores at 4 or 12 weeks after the injections (both P>0.05). The WOMAC scores and Lequesne scores at 26 and 52 weeks after the injections were significantly higher in patellofemoral arthritis group than in CP group (both P < 0.05). In both groups, the 30-m walking time and the stair ascending and descending time decreased significantly at 1, 2, 3, and 4 weeks after HA injections (all P < 0.05) without significant differences between the two groups (all P>0.05).

CONCLUSIONS

HA injection through the subpatellar route is effective for treatment of CP. HA injection produces better long-term efficacy for treatment of early CP than for advanced CP where patellofemoral arthritis occurs.

Hyaluronan synthase 2 (HAS2) overexpression diminishes the procatabolic activity of chondrocytes by a mechanism independent of extracellular hyaluronan

Osteoarthritis (OA) is a progressive degenerative disease of the joints caused in part by a change in the phenotype of resident chondrocytes within affected joints. This altered phenotype, often termed proinflammatory or procatabolic, features enhanced production of endoproteinases and matrix metallo-proteinases (MMPs) as well as secretion of endogenous inflammatory mediators. Degradation and reduced retention of the proteoglycan aggrecan is an early event in OA. Enhanced turnover of hyaluronan (HA) is closely associated with changes in aggrecan. Here, to determine whether experimentally increased HA production promotes aggrecan retention and generates a positive feedback response, we overexpressed HA synthase-2 (HAS2) in chondrocytes via an inducible adenovirus construct (HA synthase-2 viral overexpression; HAS2-OE). HAS2-OE incrementally increased high-molecular-mass HA >100-fold within the cell-associated and growth medium pools. More importantly, our results indicated that the HAS2-OE expression system inhibits MMP3, MMP13, and other markers of the procatabolic phenotype (such as TNF-stimulated gene 6 protein (TSG6)) and also enhances aggrecan retention. These markers were inhibited in OA-associated chondrocytes and in chondrocytes activated by interleukin-1β (IL1β), but also chondrocytes activated by lipopolysaccharide (LPS), tumor necrosis factor α (TNFα), or HA oligosaccharides. However, the enhanced extracellular HA resulting from HAS2-OE did not reduce the procatabolic phenotype of neighboring nontransduced chondrocytes as we had expected. Rather, HA-mediated inhibition of the phenotype occurred only in transduced cells. In addition, high HA biosynthesis rates, especially in transduced procatabolic chondrocytes, resulted in marked changes in chondrocyte dependence on glycolysis versus oxidative phosphorylation for their metabolic energy needs.

Hyaluronic Acid: Molecular Mechanisms and Therapeutic Trajectory

Hyaluronic acid (also known as hyaluronan or hyaluronate) is naturally found in many tissues and fluids, but more abundantly in articular cartilage and synovial fluid (SF). Hyaluronic acid (HA) content varies widely in different joints and species. HA is a non-sulfated, naturally occurring non-protein glycosaminoglycan (GAG), with distinct physico-chemical properties, produced by synoviocytes, fibroblasts, and chondrocytes. HA has an important role in the biomechanics of normal SF, where it is partially responsible for lubrication and viscoelasticity of the SF. The concentration of HA and its molecular weight (MW) decline as osteoarthritis (OA) progresses with aging. For that reason, HA has been used for more than four decades in the treatment of OA in dogs, horses and humans. HA produces anti-arthritic effects via multiple mechanisms involving receptors, enzymes and other metabolic pathways. HA is also used in the treatment of ophthalmic, dermal, burns, wound repair, and other health conditions. The MW of HA appears to play a critical role in the formulation of the products used in the treatment of diseases. This review provides a mechanism-based rationale for the use of HA in some disease conditions with special reference to OA.

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.

Accumulation of hyaluronic acid in stromal cells modulates osteoclast formation by regulation of receptor activator of nuclear factor kappa-B ligand expression

Hyaluronic acid (HA) has a pivotal role in bone and cartilage metabolism. In this study, we investigated the effect and underlying mechanisms of HA accumulation on the expression of receptor activator of nuclear factor kappa-B ligand (RANKL) induced by 1α,25(OH)₂D₃ and dexamethasone in stromal cells, which support osteoclastogenesis. Degradation of HA by hyaluronidase (HA'ase) treatment enhanced the expression of RANKL in ST2 cells stimulated with 1α,25(OH)₂D₃ and dexamethasone. Down-regulation of hyaluronan synthase 2 (HAS2) expression by siRNA also stimulated RANKL expression induced by 1α,25(OH)₂D₃ and dexamethasone. Results from a cell co-culture system with bone marrow cell showed that 1α,25(OH)₂D₃ and dexamethasone-induced RANKL expression in HA'ase treated- and HAS2 siRNA transfected-ST2 cells was down-regulated by treatment of cells with high molecular weight HA. In contrast, transforming growth factor-β1 (TGF-β1), which stimulates HAS2 expression and HA synthesis, down-regulated RANKL expression induced by 1α,25(OH)₂D₃ and dexamethasone. Interestingly, knockdown of has2 gene enhanced the expression of vitamin D receptor (VDR) and phosphorylation of signal transducers and activator of transcription 3 (STAT3) in ST2 cells stimulated by 1α,25(OH)₂D₃ and dexamethasone. These results indicate that accumulation of HA in bone marrow cells may affect RANKL-mediated osteoclast-supporting activity via regulation of VDR and STAT3 signaling pathways.

Determination of two fluoroquinolones and their combinations with hyaluronan effect in in vitro canine cartilage explants

Background

Previous studies reported the effect of enrofloxacin (Enro) and marbofloxacin (Mar) on cell death and alteration of the key genes involved in catabolic and anabolic processes and demonstrated the beneficial effects of hyaluronan (HA) combined with fluoroquinolones (FQs) on primary canine chondrocytes. This study further determines the effects of these treatments on canine cartilage explants in both normal and interleukin-1 beta (IL-1β)-stimulated conditions.

Methods

We examined sulfate glycosaminoglycan (s-GAG) release, uronic acid (UA) content, and safranin-O staining, as well as the expression patterns of inflammatory, extracellular matrix (ECM) component and enzymes.

Results

Enro treatment alone effectively stimulated proteoglycan anabolism by increasing UA content and glycosaminoglycans (GAGs) in normal and pre-IL-1β-stimulated explant, whereas Mar showed opposite results. The combination of HA and FQs increased s-GAG release and UA content in normal explants in addition to effective down-regulated expression of MMP3. HA reduced the adverse effects of Mar by enhancing UA and GAG contents in both normal and pre-IL-1β-explants. Moreover, HA effectively induced HAS1and ACANup-regulation and reduced MMP9, TNF, PTGS2,and NFKB1 expression for a long term.

Discussion

Our results suggest the direct effects of Enro and Mar may selectively stimulate the conditioned explants to express MMP-codinggenes and promote gene expression involved in matrix production, pro-inflammatory cytokines, and cell degradation in different directions. HA successfully reduced the adverse effects of FQs by enhancing s-GAG and UA contents and down-regulated expression of MMPs.

Stribeck Curve Analysis of Temporomandibular Joint Condylar Cartilage and Disc

Temporomandibular joint (TMJ) diseases such as osteoarthritis and disc displacement have no permanent treatment options, but lubrication therapies, used in other joints, could be an effective alternative. However, the healthy TMJ contains fibrocartilage, not hyaline cartilage as is found in other joints. As such, the effect of lubrication therapies in the TMJ is unknown. Additionally, only a few studies have characterized the friction coefficient of the healthy TMJ. Like other cartilaginous tissues, the TMJ condyles and discs are subject to changes in friction coefficient due to fluid pressurization. In addition, the friction coefficient of the TMJ is affected by the sliding direction and anatomic location. However, these previous findings have not been able to identify how all 3 of these parameters (anatomic location, sliding direction, and fluid pressurization) influence changes in friction coefficient. This study used Stribeck curves to identify differences in the friction coefficients of TMJ condyles and discs based on anatomic location, sliding direction, and amount of fluid pressurization (friction mode). Friction coefficients were measured using a cartilage on glass tribometer. Both TMJ condyle and disc friction coefficients were well described by Stribeck curves. These curves changed based on anatomic location, but very few differences in friction coefficients were observed based on sliding direction. TMJ condyles had similar boundary mode and elastoviscous mode friction coefficients to the TMJ disc, and both were lower than hyaline cartilage in other joints. The observed differences here indicate that the surface characteristics of each anatomic region cause differences in friction coefficients.

Investigational drugs for the treatment of osteoarthritis, an update on recent developments

INTRODUCTION

Osteoarthritis (OA) is the leading cause of pain, loss of function, and disability among elderly, with the knee the most affected joint. It is a heterogeneous condition characterized by complex and multifactorial etiologies which contribute to the broad variation in symptoms presentation and treatment responses that OA patients present. This poses a challenge for the development of effective treatment on OA.

AREAS COVERED

This review will discuss recent development of agents for the treatment of OA, updating our previous narrative review published in 2015. They include drugs for controlling local and systemic inflammation, regulating articular cartilage, targeting subchondral bone, and relieving pain.

EXPERT OPINION

Although new OA drugs such as monoclonal antibodies have shown marked effects and favorable tolerance, current treatment options for OA remain limited. The authors believe there is no miracle drug that can be used for all OA patients'; treatment and disease stage is crucial for the effectiveness of drugs. Therefore, early diagnosis, phenotyping OA patients and precise therapy would expedite the development of investigational drugs targeting at symptoms and disease progression of OA.

Notochordal cell matrix as a bioactive lubricant for the osteoarthritic joint

Notochordal cell derived matrix (NCM) can induce regenerative effects on nucleus pulposus cells and may exert such effects on chondrocytes as well. Furthermore, when dissolved at low concentrations, NCM forms a viscous fluid with potential lubricating properties. Therefore, this study tests the feasibility of the use of NCM as a regenerative lubricant for the osteoarthritic joint. Chondrocyte-seeded alginate beads were cultured in base medium (BM), BM with NCM (NCM), or BM with TGF-β1 (TGF), as well as BM and NCM treated with IL-1β. NCM increased GAG deposition and cell proliferation (stronger than TGF), and GAG/DNA ratio and hydroxyproline content (similar to TGF). These effects were maintained in the presence of IL-1β. Moreover, NCM mitigated expression of IL-1β-induced IL-6, IL-8, ADAMTS-5 and MMP-13. Reciprocating sliding friction tests of cartilage on glass were performed to test NCM's lubricating properties relative to hyaluronic acid (HA), and showed a dose-dependent reduction in coefficient of friction with NCM, similar to HA. NCM has anabolic and anti-inflammatory effects on chondrocytes, as well as lubricating properties. Therefore, intra-articular NCM injection may have potential as a treatment to minimize pain while restoring the affected cartilage tissue in the osteoarthritic joint.

Glycosaminoglycans from fish swim bladder: isolation, structural characterization and bioactive potential

The swim bladder of fish is an internal gas-filled organ that allows fish to control their buoyancy and swimming depth. Fish maws (the dried swim bladders of fish) have been used over many centuries as traditional medicines, tonics and a luxurious gourmet food in China and Southeast Asia. Little is known about the structural information of polysaccharides comprising this important functional material of fish tissue. In the present study, the total glycosaminoglycan (GAG) from fish maw was characterized. Two GAGs were identified, chondroitin sulfate (CS, having a molecular weight of 18-40 kDa) and heparan sulfate (HS), corresponding to 95% and 5% of the total GAG, respectively. Chondroitinase digestion showed that the major CS GAG was composed of ΔUA-1 → 3-GalNAc4S (59.7%), ΔUA-1 → 3-GalNAc4,6S (36.5%), ΔUA-1 → 3-GalNAc6S (2.2%) and ΔUA-1 → 3-GalNAc (1.6%) disaccharide units. ¹H-NMR analysis and degradation with specific chondroitinases, both CS-type A/C and CS-type B were present in a ratio of 1.4:1. Analysis using surface plasmon resonance showed that fibroblast growth factor (FGF)-2 bound to the CS fraction (K_D = 136 nM). These results suggest that this CS may be involved in FGF-signal pathway, mediating tissue repair, regeneration and wound healing. The CS, as the major GAG in fish maw, may have potential pharmacological activity in accelerating wound healing.

Hyaluronic acid vs corticosteroids in symptomatic knee osteoarthritis: a mini-review of the literature

Introduction

Although intra-articular injections of hyaluronic acid (HA) are common non-operative measures used in clinical practice in the management of symptomatic osteoarthritis, there is a great controversy on their efficacy and safety compared to corticosteroids (CSs).

Efficacy

Conflicting results have been reported in clinical trials and meta-analysis due to methodological differences in study design, along with collection, analysis, and interpretation of data. Even if some studies reported small or no differences of HA compared with CSs (or inferred that HA is not more effective than saline as a placebo), in general CSs have shown to be superior in the short term (especially on pain control), while better results have been reported with HA at subsequent evaluations, but with only a moderate effect after 26 weeks.

Safety

Mild or moderate adverse events have generally been reported after HA injections, the most common being injection site pain. HA is generally considered safe compared to CSs or saline. Furthermore, HA has shown to be safe also after a previous course of injections.

Conclusions

Conflicting results have been reported on the efficacy and safety of HA. Guidelines are controversial and in most of the cases "uncertain" recommendations are provided due to inconclusive evidence in literature. However, HA does not seem to have significantly higher side effects when compared to saline or CSs injections, and provides better medium-term control of symptoms in patients with mild to moderate knee osteoarthritis.

Intra-articular hyaluronic acid injection in treating knee osteoarthritis: assessing risk of bias in systematic reviews with ROBIS tool

OBJECTIVES

Intra-articular injection of hyaluronic acid (HA) is a common, yet controversial therapeutic option in treating knee osteoarthritis (OA). The purpose of the present study was to assess the risk of bias (RoB) of systematic reviews (SRs) and to summarize available evidence of HA in treating knee OA.

METHODS

A systematic search of SRs published through to December 2016 was conducted using the MEDLINE, EMBASE and Cochrane Library. The RoB of included SRs was assessed by ROBIS tool. In addition, the methodological quality of primary studies in SRs with low RoB was evaluated according to the Cochrane Handbook. The evidence quality of each primary outcome of SRs with low RoB was determined by the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system.

RESULTS

Thirty-one SRs were eligible for inclusion. According to the ROBIS tool, there were 13 SRs with low RoB, 16 with high RoB and two with unclear RoB. The methodological quality of a total of 135 primary studies was evaluated and summarized. Forty-two outcomes from these 13 SRs were classified into the four following quality levels based on the GRADE approach: three outcomes with high quality, eight with moderate quality, 12 with low quality and 19 with very low quality.

CONCLUSIONS

This study evaluated RoB in SRs for managing knee OA with HA and assessed the evidence quality of each primary outcome in SRs with low RoB. These results can help users of SRs to improve the process of SR assessment in developing overviews or guidelines, leading to more reliable recommendations for improvements in treating knee OA. Registration: PROSPERO ((http://www.crd.york.ac.uk/PROSPERO) [CRD42017057384].

Enhanced Biosynthesis of Hyaluronic Acid Using Engineered Corynebacterium glutamicum Via Metabolic Pathway Regulation

Hyaluronic acid (HA) is a polysaccharide used in many industries such as medicine, surgery, cosmetics, and food. To avoid potential pathogenicity caused by its native producer, Streptococcus, efforts have been made to create a recombinant host for HA production. In this work, a GRAS (generally recognized as safe) strain, Corynebacterium glutamicum, is engineered for enhanced biosynthesis of HA via metabolic pathway regulation. Five enzymes (HasA-HasE) involved in the HA biosynthetic pathway are highlighted, and eight diverse operon combinations, including HasA, HasAB, HasAC, HasAD, HasAE, HasABC, HasABD, and HasABE, are compared. HasAB and HasABC are found to be optimal for HA biosynthesis in C. glutamicum. To meet the energy demand for HA synthesis, the metabolic pathway that produces lactate is blocked by knocking out the lactate dehydrogenase (LDH) gene using single crossover homologous recombination. Engineered C. glutamicum/Δldh-AB is superior and had a significantly higher HA titer than C. glutamicum/Δldh-ABC. Batch and fed-batch cultures of C. glutamicum/Δldh-AB are performed in a 5-L fermenter. Using glucose feeding, the maximum HA titer reached 21.6 g L^-1 , more than threefolds of that of the wild-type Streptococcus. This work provides an efficient, safe, and novel recombinant HA producer, C. glutamicum/Δldh-AB, via metabolic pathway regulation.

Efficacy of intra-articular hyaluronic acid injections in hip osteoarthritis: a meta-analysis of randomized controlled trials

There is less credible evidence of using of intra-articular injections of hyaluronic acid (HA) to treat hip osteoarthritis (OA). This study is to determine the therapeutic effects and risk of adverse events of HA administration for hip OA. The MEDLINE, Cochrane of Systematic Reviews, Cochrane Clinical Trial Register and EMBASE, were searched for articles published. Eligible studies were limited to trials of HA with a randomized design. A total of six studies were included in this the meta-analysis. The pooled effect size of improved pain scores from pretreatment was –0.72 (95%CI; –1.06 to –0.39; P < 0.05). The standardized mean difference (SMD) of improved Lequesne's index and McMaster Universities Osteoarthritis Index (WOMAC) was –0.74 (95%CI, –1.42 to –0.51; P < 0.05) and –7.75 (95%CI, –14.28 to –1.21; P < 0.05), respectively. The pooled effect size of improved pain scores compared HA with different controls was 0.03 (95%CI; –0.20 to 0.26; P < 0.05). The SMD of improved Lequesne's index and WOMAC was –0.24 (95%CI, –0.50 to 0.02; P > 0.05) and –0.13 (95%CI, 0.64 to 0.37; P > 0.05). There were no significant differences between HA and control group in adverse events (RR: 0.94; 95%CI, 0.41 to 2.20; P > 0.05). Intra-articular HA in hip OA can significantly reduce pain and improve functional recovery when compared with the condition before treatment. However, there seems no significant difference between HA and saline or other treatments. Currently, available evidence indicated that intra-articular HA in hip OA would not be increased risk of adverse events.

Long-term clinical benefit and cost-effectiveness of an 8-week multimodal knee osteoarthritis management program incorporating intra-articular sodium hyaluronate (Hyalgan®) injections

Background

Given the poor long-term effectiveness of focused nonsurgical knee osteoarthritis (OA) treatments, alternative therapies are needed for patients who have unsuccessfully exhausted nonsurgical options.

Methods

A telephone interview was conducted in patients who participated in a single 8-week multimodal knee OA treatment program (mean follow-up: 3.7 years, range: 2.7–4.9 years). The program consisted of five intra-articular knee injections of sodium hyaluronate (Hyalgan^®), with each injection given 1 week apart, structured physical therapy, knee bracing, and patient education. Clinical outcomes included knee pain severity, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) subscores, current medication use, and history of total knee arthroplasty. Base-case, subgroup, and sensitivity analyses were conducted to determine the incremental cost-effectiveness ratio (ICER) of the treatment program with comparisons made to historical literature controls undergoing usual care.

Results

A total of 218 patients (54%) provided long-term follow-up data. Knee pain severity decreased 60% and WOMAC subscores decreased 33%–42% compared to baseline (all p<0.001). Total knee arthroplasty was performed in 22.8% (81/356) of knees during followup. The treatment program was highly cost-effective compared to usual care with a base-case ICER of $6,000 per quality-adjusted life year (QALY). Results of subgroup analyses, one-way deterministic sensitivity analyses, and second-order probabilistic sensitivity analyses resulted in ICERs ranging from $3,996 to $10,493 per QALY. The percentage of simulations with an ICER below willingness-to-pay limits was 97.2%, 98.9%, and 99.4% for the $50,000, $100,000, and $150,000 per QALY thresholds, respectively.

Conclusion

Participation in a single 8-week knee OA treatment program, which included one cycle of five intra-articular knee injections of sodium hyaluronate given at weekly intervals, is highly cost-effective and provides clinically meaningful reductions in patient symptoms that are maintained over 3.7 years mean follow-up.

Role of tumor microenvironment in tumorigenesis

Tumorigenesis is a complex and dynamic process, consisting of three stages: initiation, progression, and metastasis. Tumors are encircled by extracellular matrix (ECM) and stromal cells, and the physiological state of the tumor microenvironment (TME) is closely connected to every step of tumorigenesis. Evidence suggests that the vital components of the TME are fibroblasts and myofibroblasts, neuroendocrine cells, adipose cells, immune and inflammatory cells, the blood and lymphatic vascular networks, and ECM. This manuscript, based on the current studies of the TME, offers a more comprehensive overview of the primary functions of each component of the TME in cancer initiation, progression, and invasion. The manuscript also includes primary therapeutic targeting markers for each player, which may be helpful in treating tumors.

High molecular weight hyaluronic acid regulates MMP13 expression in chondrocytes via DUSP10/MKP5

To determine the effect of high molecular weight hyaluronic acid (HA) on matrix metalloproteinase 13 (MMP13) expression induced by tumor necrosis factor α (TNF-α) in chondrocytes. Human chondrocytic C28/I2 cells were incubated with TNF-α and HA. In some experiments, the cells were pre-incubated with a CD44 function-blocking monoclonal antibody (CD44 mAb) prior to addition of TNF-α and HA. The expression of MMP13 was determined by real-time reverse-transcription polymerase chain reaction (RT-PCR) and an enzyme linked immunosorbent assay, while the phosphorylation of signaling molecules was measured by western blot analysis. The transcriptional activity of activator protein 1 (AP-1) was analyzed by a reporter assay. To further clarify the molecular mechanisms of HA in MMP13 regulation, the expression level of dual-specificity protein phosphatase 10 (DUSP10)/mitogen-activated protein kinases phosphatase 5 (MKP5) in HA-treated chondrocytes was assessed by real-time RT-PCR, western blotting, and immunofluorescence microscopy. HA decreased MMP13 mRNA and protein expression induced by TNF-α. Blockage of HA-CD44 binding by CD44 mAb suppressed HA-mediated inhibition of MMP13. HA inhibited transient phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-jun NH₂ -terminal kinase (JNK) induced by TNF-α. Reporter assay findings also revealed that pre-treatment with HA inhibited the transcriptional activity of AP-1 mediated by TNF-α. Moreover, HA induced the expression of DUSP10/MKP5, a negative regulator of p38 MAPK and JNK pathways. These results indicate that HA-CD44 interactions downregulate TNF-α-induced MMP13 expression via regulation of DUSP10/MKP5, suggesting that HA plays an important role as a regulatory factor in cartilage degradation. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:331-339, 2017.

Avoidance of Total Knee Arthroplasty in Early Osteoarthritis of the Knee with Intra-Articular Implantation of Autologous Activated Peripheral Blood Stem Cells versus Hyaluronic Acid: A Randomized Controlled Trial with Differential Effects of Growth Factor Addition

In this randomized controlled trial, in early osteoarthritis (OA) that failed conservative intervention, the need for total knee arthroplasty (TKA) and WOMAC scores were evaluated, following a combination of arthroscopic microdrilling mesenchymal cell stimulation (MCS) and repeated intra-articular (IA) autologous activated peripheral blood stem cells (AAPBSCs) with growth factor addition (GFA) and hyaluronic acid (HA) versus IA-HA alone. Leukapheresis-harvested AAPBSCs were administered as three weekly IA injections combined with HA and GFA (platelet-rich plasma [PRP] and granulocyte colony-stimulating factor [hG-CSF]) and MCS in group 1 and in group 2 but without hG-CSF while group 3 received IA-HA alone. Each group of 20 patients was evaluated at baseline and at 1, 6, and, 12 months. At 12 months, all patients in the AAPBSC groups were surgical intervention free compared to three patients needing TKA in group 3 (p < 0.033). Total WOMAC scores showed statistically significant improvements at 6 and 12 months for the AAPBSC groups versus controls. There were no notable adverse events. We have shown avoidance of TKA in the AAPBSC groups at 12 months and potent, early, and sustained symptom alleviation through GFA versus HA alone. Differential effects of hG-CSF were noted with an earlier onset of symptom alleviation throughout.

No Effects of Early Viscosupplementation After Arthroscopic Partial Meniscectomy: A Randomized Controlled Trial

BACKGROUND

The management of the postoperative period after knee arthroscopic surgery may be challenging because surgical trauma deeply alters the joint microenvironment, causing the release of several catabolic molecules and proinflammatory factors that might slow down functional recovery. The possibility of using hyaluronic acid (HA) to promote postoperative pain relief and expedite functional improvement seems attractive, considering its biological properties.

PURPOSE

The aim of the present double-blind randomized controlled trial was to evaluate the effects, in terms of pain control and functional recovery, provided by a single HA injection performed at the end of arthroscopic meniscectomy.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 90 patients, 18 to 55 years old, were included according to the following criteria: (1) chronic, symptomatic meniscal tears requiring partial resection; (2) a healthy contralateral knee; (3) no previous surgery on the index knee; and (4) no other concurrent articular lesions requiring surgical treatment (eg, cartilage or ligament injuries). Patients were randomized into 2 treatment groups: one underwent meniscectomy alone, whereas the other also received an injection of 3 mL HA at the end of the procedure. All patients were evaluated at baseline and then at 15, 30, 60, and 180 days using the following tools: International Knee Documentation Committee (IKDC) subjective, Knee injury and Osteoarthritis Outcome Score (KOOS), visual analog scale (VAS) for pain, VAS for general health status, and Tegner scores. The transpatellar circumference and active and passive ranges of motion were also recorded during the follow-up evaluations.

RESULTS

No major adverse events were reported using HA postoperatively. A statistically significant increase in all the clinical scores was reported in both treatment groups, but no significant intergroup difference was documented at any follow-up evaluation. No difference was observed also in the objective measurements. The mean time to return to full sports activity was not different between groups, and a comparable satisfaction rate was recorded in both treatment groups.

CONCLUSION

Early postoperative viscosupplementation did not provide significant clinical benefits after arthroscopic meniscectomy. Despite the lack of major adverse events, the administration of a single HA injection at the end of the surgical procedure is not a successful strategy to provide either faster functional recovery or symptomatic improvement after meniscectomy.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02629380.

Hyaluronic acid in the management of osteoarthritis: injection therapies innovations

Osteoarthritis (OA) is a chronic degenerative joint disease characterized by pain and progressive functional limitation. Viscosupplementation with intra-articular (IA) hyaluronic acid (HA) could be a treatment option in OA, however recommendations made in different international guidelines for the non-surgical management of OA are not always concordant with regard to the role of IA injection therapies. Results from a recent Italian Consensus Conference underline how IA-HA to treat OA represents a widely used therapy in Italy. Specifically high molecular weight HA, cross-linked HA, and mobile reticulum HA are considered very useful to treat the OA joints from a great number of expert in Italy. These kinds of HA could reduce the NSAIDs intake, furthermore high-molecular weight and mobile reticulum HA are considered to be able to delay or avoid a joint prosthetic implant. This mini review highlights the results obtained from the Italian Consensus Conference "Appropriateness of clinical and organizational criteria for intra-articular injection therapies in osteoarthritis" and give further indication about innovation in IA-HA therapies.