Hyaluronan and Derivatives: An In Vitro Multilevel Assessment of Their Potential in Viscosupplementation

Abstract

In this research work, viscosupplements based on linear, derivatized, crosslinked and complexed HA forms were extensively examined, providing data on the hydrodynamic parameters for the water-soluble-HA-fraction, rheology, sensitivity to enzymatic hydrolysis and capacity to modulate specific biomarkers’ expression in human pathological chondrocytes and synoviocytes. Soluble HA ranged from 0 to 32 mg/mL and from 150 to 1330 kDa MW. The rheological behavior spanned from purely elastic to viscoelastic, suggesting the diversity of the categories that are suitable for restoring specific/different features of the healthy synovial fluid. The rheological parameters were reduced in a diverse manner upon dilution and hyaluronidases action, indicating different durations of the viscosupplementation effect. Bioactivity was found for all the samples, increasing the expression of different matrix markers (e.g., hyaluronan-synthase); however, the hybrid cooperative complexes performed better in most of the experiments. Hybrid cooperative complexes improved COLII mRNA expression (~12-fold increase vs. CTR), proved the most effective at preserving cell phenotype. In addition, in these models, the HA samples reduced inflammation. IL-6 was down-regulated vs. CTR by linear and chemically modified HA, and especially by hybrid complexes. The results represent the first comprehensive panel of data directly comparing the diverse HA forms for intra-articular injections and provide valuable information for tailoring products’ clinical use as well as for designing new, highly performing HA-formulations that can address specific needs.

Highly Concentrated Stabilized Hybrid Complexes of Hyaluronic Acid: Rheological and Biological Assessment of Compatibility with Adipose Tissue and Derived Stromal Cells towards Regenerative Medicine

“…On the other hand, it appears that, at a high concentration (45 mg/mL), the HA hybrid complex showed the properties of a viscous liquid as expected, but the entanglement seems to be superior to that of HCC (32 mg/mL), thus displaying a potentially better mechanical performance and reducing deformation under the influence of external forces. As a matter of fact, HL 90 shows higher G ′ at 1 Hz and lower tan δ than HCC (32 mg/mL); in addition, its curve of tan δ versus frequency (>2.5 Hz) showed lower values than the one recorded for Sinovial HL ® [18,21]. These data suggest a further little step, with this higher concentration of the hybrid complexes, towards the rheological characteristics of low crosslinked soluble gels.…”

“…In the context of adipose regeneration, it is crucial to emphasize the requirement for a suitably viscous or rigid support or scaffold to ensure the retention of injected or implanted cells in a defined location or to facilitate prolonged interaction with resident stem cells, thereby enabling the completion of their intended functions. Regarding this matter, hydroxyapatite-based gels seem to be highly suitable for this purpose due to their widely recognized viscoelastic qualities, but they may induce inflammation through the NLRP3 inflammasome in vitro and in vivo [18]. However, compelling evidence indicates that HA, a key component of these products, does not elicit an immune response and undergoes total in vivo degradation within a span of 6 months [19].…”

Potential of Biofermentative Unsulfated Chondroitin and Hyaluronic Acid in Dermal Repair

“…The mechanical spectrum highlighted viscoelastic properties typical of entangled networks with relative dynamic moduli values indicating a rheological behavior turning from viscous to elastic with increasing frequency, similarly to properties of HHA solutions [16]. It is interesting that, due to the position of G'-G" crossover, the formula behaves similarly to crosslinked products over a rather wide range of frequencies [17,18].…”

“…Measurements were carried out using a Physica MCR301 oscillatory rheometer (Anton Paar, Germany) as previously reported with slight modifications [16,18]. Amplitude sweep and frequency sweep tests were performed at 37 °C, using a CP 50-1 geometry (cone diameter 49.968 mm, cone angle 0.994°, truncation 100μm).…”

Chemical Modification of Hyaluronan and Their Biomedical Applications

“…The simplest usage of HA is in form of solutions in physiological buffers, where different properties are achieved by varying the concentration as well as the molecular weight of HA (Nicholls et al, 2018). Hybrid complexes composed of thermally treated HMW-HA and LMW-HA based on biophysical interactions between hydrogen bonds of HA chains are explored as injectable polymer matrix especially for the treatment of osteoarthritis (Stellavato et al, 2019;La Gatta et al, 2021). Chemical modification strategies targeting the preponderantly present carboxylic acid groups, or primary and secondary hydroxyl groups and, after deamidation, the N-acetyl groups, give rise to HA derivatives with altered biological as well as material properties (Figure 14).…”