Analytical aspects of pharmaceutical grade chondroitin sulfates

Chondroitin sulfate from heads of corb: Recovery, structural analysis and assessment of anticoagulant activity

In this study, glycosaminoglycans (GAGs) were extracted from corb (Sciaena umbra) heads and thoroughly examined for their structure. Through cellulose acetate electrophoresis, the GAGs were identified as chondroitin sulfate (CS), with a recovery yield of 10.35 %. The CS exhibited notable characteristics including a high sulfate content (12.4 %) and an average molecular weight of 38.32 kDa. Further analysis via 1H NMR spectroscopy and SAX-HPLC revealed that the CS primarily consisted of alternating units predominantly composed of monosulfated disaccharides at positions 6 and 4 of GalNAc (52.6 % and 38.8 %, respectively). The ratio of sulfate groups between positions 4 and 6 of GalNAc (4/6 ratio) was approximately 0.74, resulting in an overall charge density of 0.98. Thermal properties of the CS were assessed using techniques such as differential scanning calorimetry and thermogravimetric analysis. Notably, the CS demonstrated concentration-dependent prolongation of activated partial thromboplastin time (aPTT) and thrombin time (TT) while showing no effect on platelet function. At 200 μg/mL, aPTT and TT coagulation times were 1.4 and 3.7 times faster than the control, respectively. These findings suggest that CS derived from corb heads holds promise as an anticoagulant agent for therapy, although further clinical investigations are necessary to validate its efficacy.

Future proofing of chondroitin sulphate production: Importance of sustainability and quality for the end-applications

Chondroitin sulphates (CSs) are the most well-known glycosaminoglycans (GAGs) found in any living organism, from microorganisms to invertebrates and vertebrates (including humans), and provide several health benefits. The applications of CSs are numerous including tissue engineering, osteoarthritis treatment, antiviral, cosmetics, and skincare applications. The current commercial production of CSs mostly uses animal, bovine, porcine, and avian tissues as well as marine organisms, marine mammals, sharks, and other fish. The production process consists of tissue hydrolysis, protein removal, and purification using various methods. Mostly, these are chemical-dependent and are complex, multi-step processes. There is a developing trend for abandonment of harsh extraction chemicals and their substitution with different green-extraction technologies, however, these are still in their infancy. The quality of CSs is the first and foremost requirement for end-applications and is dependent on the extraction and purification methodologies used. The final products will show different bio-functional properties, depending on their origin and production methodology. This is a comprehensive review of the characteristics, properties, uses, sources, and extraction methods of CSs. This review emphasises the need for extraction and purification processes to be environmentally friendly and gentle, followed by product analysis and quality control to ensure the expected bioactivity of CSs.

Disaccharide compositional analysis of chondroitin sulphate using WAX HILIC-MS with pre-column procainamide labelling; application to the placenta in pre-eclampsia

Chondroitin sulphate (CS) and dermatan sulphate are negatively charged linear heteropolysaccharides. These glycosaminoglycans (GAG) are involved in cellular signalling via binding to growth factors. CS is expressed in a range of tissue and biological fluids and is highly expressed in the placenta. There is evidence that decorin; a CS proteoglycan is significantly decreased in pre-eclampsia and fetal growth restriction. It is considered that GAG chain composition may influence cellular processes that are altered in pre-eclampsia. The goal of the present study was to develop an LC-MS method with precolumn procainamide labelling for the disaccharide compositional analysis of CS. The method was used to investigate whether the disaccharide composition of placenta-extracted CS is altered in pre-eclampsia. The study revealed differential disaccharide compositions of placental chondroitin sulphate between pre-eclampsia and other pregnancy conditions. This suggests that the method may have diagnostic potential for pregnancy disorders. Furthermore, the findings suggest that CS sulphation might play a significant role in maternal labour.

Thermally stabilized chondroitin sulfate-hemoglobin nanoparticles and their interaction with bioactive compounds

The preparation of nanoparticles (NPs) based on hemoglobin (Hb) with a fully biocompatible methodology is presented. The spontaneous formation of electrostatic complexes of Hb with chondroitin sulfate (CS) at pH 4 in the polysaccharide/protein mass ratio regime where charge neutrality is met leads to spherical nanostructures with monomodal hydrodynamic radii distribution in the range of 50-100 nm. The integrity of the electrostatic complexes is disturbed at pH 7 as the net electric charge of Hb is very low. Treating the NPs at mildly elevated temperature stabilizes them against the pH increase taking advantage of Hb's ability of unfolding and self-associating upon thermal treatment. The NPs surface charge is pH-tunable and changes from positive to strongly negative upon pH increase to 7 proving the presence of negative surface patches of Hb and CS segments in their exterior. The α-helix content of Hb does not change significantly by thermal treatment. The NPs are found to bind the bioactive compounds curcumin and β-carotene and are stable in solutions with high salt content. This investigation introduces a straightforward method to formulate Hb in NPs with possibilities in the nanodelivery of nutrients and drugs.

Cryogel Scaffolds for Tissue-Engineering: Advances and Challenges for Effective Bone and Cartilage Regeneration

Critical-sized bone defects and articular cartilage injuries resulting from trauma, osteonecrosis, or age-related degeneration can be often non-healed by physiological repairing mechanisms, thus representing a relevant clinical issue due to a high epidemiological incidence rate. Novel tissue-engineering approaches have been proposed as an alternative to common clinical practices. This cutting-edge technology is based on the combination of three fundamental components, generally referred to as the tissue-engineering triad: autologous or allogenic cells, growth-stimulating factors, and a scaffold. Three-dimensional polymer networks are frequently used as scaffolds to allow cell proliferation and tissue regeneration. In particular, cryogels give promising results for this purpose, thanks to their peculiar properties. Cryogels are indeed characterized by an interconnected porous structure and a typical sponge-like behavior, which facilitate cellular infiltration and ingrowth. Their composition and the fabrication procedure can be appropriately tuned to obtain scaffolds that match the requirements of a specific tissue or organ to be regenerated. These features make cryogels interesting and promising scaffolds for the regeneration of different tissues, including those characterized by very complex mechanical and physical properties, such as bones and joints. In this review, state-of-the-art fabrication and employment of cryogels for supporting effective osteogenic or chondrogenic differentiation to allow for the regeneration of functional tissues is reported. Current progress and challenges for the implementation of this technology in clinical practice are also highlighted.

Composition and Anticoagulant Potential of Chondroitin Sulfate and Dermatan Sulfate from Inedible Parts of Garfish (Belone belone)

Glycosaminoglycans (GAGs) play a crucial role due to their significant biomedical functions. Chondroitin sulfate (CS) and dermatan sulfate (DS), the main representative family of GAGs, were extracted and purified from garfish (Belone belone) by-products, i.e., skin (GSB), bones (GCB), and heads (GHB), and their composition and anticoagulant activity were investigated. CS/DS were purified by ion-exchange chromatography with yields of 8.1% for heads, 3.7% for skin, and 1.4% for bones. Cellulose acetate electrophoresis was also explored for analyzing the extracted CS/DS. Interestingly, GHB, GSB, and GCB possessed sulfate contents of 21 ± 2%, 20 ± 1%, and 20 ± 1.5%, respectively. Physico-chemical analysis showed that there were no significant differences (p > 0.05) between the variances for sulfate, uronic acid, and total sugars in the GAGs extracted from the different parts of fish. Disaccharide analysis by SAX-HPLC showed that the GSB and GCB were predominately composed of ΔDi-4S [ΔUA-GalNAc 6S] (74.78% and 69.22%, respectively) and ΔDi-2,4S [ΔUA2S-GalNAc 4S] (10.92% and 6.55%, respectively). However, the GHB consisted of 25.55% ΔDi-6S [ΔUA-GalNAc 6S] and 6.28% ΔDi-2,6S [ΔUA2S-GalNAc 4S]. Moreover, classical anticoagulation tests were also used to measure their anticoagulant properties in vitro, which included the activated partial thromboplastin time, prothrombin time, and thrombin time. The CS/DS isolated from garfish by-products exhibited potent anticoagulant effects. The purified CS/DS showed exceptional anticoagulant properties according to this research and can be considered as a new agent with anticoagulant properties.

A Review of Chondroitin Sulfate's Preparation, Properties, Functions, and Applications

Chondroitin sulfate (CS) is a natural macromolecule polysaccharide that is extensively distributed in a wide variety of organisms. CS is of great interest to researchers due to its many in vitro and in vivo functions. CS production derives from a diverse number of sources, including but not limited to extraction from various animals or fish, bio-synthesis, and fermentation, and its purity and homogeneity can vary greatly. The structural diversity of CS with respect to sulfation and saccharide content endows this molecule with distinct complexity, allowing for functional modification. These multiple functions contribute to the application of CS in medicines, biomaterials, and functional foods. In this article, we discuss the preparation of CS from different sources, the structure of various forms of CS, and its binding to other relevant molecules. Moreover, for the creation of this article, the functions and applications of CS were reviewed, with an emphasis on drug discovery, hydrogel formation, delivery systems, and food supplements. We conclude that analyzing some perspectives on structural modifications and preparation methods could potentially influence future applications of CS in medical and biomaterial research.

Chondroitin sulfate supplementation improves clinical outcomes in a murine model of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) continues to be a devastating disease in preterm neonates and has a paucity of medical management options. Chondroitin sulfate (CS) is a naturally occurring glycosaminoglycan (GAG) in human breast milk (HM) and has been shown to reduce inflammation. We hypothesized that supplementation with CS in an experimental NEC model would alter microbial diversity, favorably alter the cytokine profile, and (like other sulfur compounds) improve outcomes in experimental NEC via the eNOS pathway. NEC was induced in 5-day-old pups. Six groups were studied (n = 9-15/group): (1) WT breastfed and (2) Formula fed controls, (3) WT NEC, (4) WT NEC + CS, (5) eNOS KO (knockout) NEC, and (6) eNOS KO NEC + CS. Pups were monitored for clinical sickness score and weights. On postnatal day 9, the pups were killed. Stool was collected from rectum and microbiome analysis was done with 16 s rRNA sequencing. Intestinal segments were examined histologically using a well-established injury scoring system and segments were homogenized and analyzed for cytokine profile. Data were analyzed using GraphPad Prism with p < 0.05 considered significant. CS supplementation in formula improved experimental NEC outcomes when compared to NEC alone. CS supplementation resulted in similar improvement in NEC in both the WT and eNOS KO mice. CS supplementation did not result in microbial changes when compared to NEC alone. Our data suggest that although CS supplementation improved outcomes in NEC, this protection is not conferred via the eNOS pathway or alteration of microbial diversity. CS therapy in NEC does improve the intestinal cytokine profile and further experiments will explore the mechanistic role of CS in altering immune pathways in this disease.

Chondroitin Sulfate Supplements for Osteoarthritis: A Critical Review

Over the years, chondroitin sulfate (CS) has been used as a slow-acting drug for the treatment of osteoarthritis, for the reduction of pain and improvement of function, and for its disease-modifying properties by limiting cartilage volume loss and joint space narrowing progression. However, there have been inconsistencies in published trials regarding clinical efficacy, with reports of a lack of significant effects compared to placebo. The therapeutic effects of chondroitin sulfate may depend on many variables, such as the source of origin, purity, and contamination with by-products. Another source of confusion may be related to the fact that CS is commonly combined with glucosamine, which makes it challenging to isolate the specific contribution of chondroitin to the therapeutic outcome. This is aggravated by the fact that CS supplements, used in many countries, are not regulated, and labels wrongly claim high levels of purity. Many of these inferior CS products may have been used in clinical trials, which may have had limited but significant results. This has led to recent recommendations to opt for higher-purity pharmacologic-grade CS for the treatment of OA. This article aims to provide an up-to-date view of the current literature regarding the biological effects and efficacy of CS and discusses the quality of available chondroitin sulfate supplements and the current direction in CS investigation. This review concludes that pharmacologic-grade CS supplements may have clinically significant benefits when properly standardized; however, high-quality evidence from properly designed clinical trials is still needed to draw definitive conclusions about clinical efficacy in osteoarthritis.

Fucosylated heparan sulfate from the midgut gland of Patinopecten yessoensis

The structural and functional relationships of glycosaminoglycans (GAGs) derived from marine organisms have been investigated, suggesting that marine invertebrates, particularly Bivalvia, are abundant sources of highly sulfated or branched GAGs. In this study, we identified a novel fucosylated heparan sulfate (Fuc-HS) from the midgut gland of the Japanese scallop, Patinopecten yessoensis. Scallop HS showed resistance to GAG-degrading enzymes, including chondroitinases and heparinases, and susceptibility to heparinases increased when scallop HS was treated with mild acid hydrolysis, which removes the fucosyl group. Moreover, ¹H NMR detected significant signals near 1.2-1.3 ppm corresponding to the H-6 methyl proton of fucose residues and small H-3 (3.59 ppm) or H-2 (3.39 ppm) signals of glucuronate (GlcA) were detected, suggesting that the fucose moiety is attached to the C-3 position of GlcA in scallop HS. GC-MS detected peaks corresponding to 1, 3, 5-tri-O-acetyl-2, 4-di-O-methyl-_L-fucitol and 1, 4, 5-tri-O-acetyl-2, 3-di-O-methyl-_L-fucitol, suggesting that the fucose moiety is 3-O- or 4-O-sulfated. Furthermore, scallop HS showed anti-coagulant and neurite outgrowth-promoting (NOP) activities. These results suggest that the midgut gland of scallops is a valuable source of Fuc-HS with biological activities.

Structural Characterization and Glycosaminoglycan Impurities Analysis of Chondroitin Sulfate from Chinese Sturgeon

Chinese sturgeon was an endangered cartilaginous fish. The success of artificial breeding has promoted it to a food fish and it is now beginning to provide a new source of cartilage for the extraction of chondroitin sulfate (CS). However, the structural characteristics of sturgeon CS from different tissues remain to be determined in more detail. In this study, CSs from the head, backbone, and fin cartilage of Chinese sturgeon were individually purified and characterized for the first time. The molecular weights, disaccharide compositions, and oligosaccharide sulfation patterns of these CSs are significantly different. Fin CS (SFCS), rich in GlcUAα1-3GalNAc(4S), has the biggest molecular weight (26.5 kDa). In contrast, head CS (SHCS) has a molecular weight of 21.0 kDa and is rich in GlcUAα1-3GalNAc(6S). Most features of backbone CS (SBCS) are between the former two. Other glycosaminoglycan impurities in these three sturgeon-derived CSs were lower than those in other common commercial CSs. All three CSs have no effect on the activity of thrombin or Factor Xa in the presence of antithrombin III. Hence, Chinese sturgeon cartilage is a potential source for the preparation of CSs with different features for food and pharmaceutical applications.

Chondroitin sulfate-based composites: a tour d'horizon of their biomedical applications

Chondroitin sulfate (CS), a natural anionic mucopolysaccharide, belonging to the glycosaminoglycan family, acts as the primary element of the extracellular matrix (ECM) of diverse organisms. It comprises repeating units of disaccharides possessing β-1,3-linked N-acetyl galactosamine (GalNAc), and β-1,4-linked D-glucuronic acid (GlcA), and exhibits antitumor, anti-inflammatory, anti-coagulant, anti-oxidant, and anti-thrombogenic activities. It is a naturally acquired bio-macromolecule with beneficial properties, such as biocompatibility, biodegradability, and immensely low toxicity, making it the center of attention in developing biomaterials for various biomedical applications. The authors have discussed the structure, unique properties, and extraction source of CS in the initial section of this review. Further, the current investigations on applications of CS-based composites in various biomedical fields, focusing on delivering active pharmaceutical compounds, tissue engineering, and wound healing, are discussed critically. In addition, the manuscript throws light on preclinical and clinical studies associated with CS composites. A short section on Chondroitinase ABC has also been canvassed. Finally, this review emphasizes the current challenges and prospects of CS in various biomedical fields.

Natural Compounds Affecting Inflammatory Pathways of Osteoarthritis

Osteoarthritis (OA) is the most common type of arthritis and chronic joint disease, affecting more than 240 million people worldwide. Although there are numerous advances in using drugs in treating OA, the use of natural compounds has aroused much interest among researchers due to their safety margin. Recent discovery shows that natural compounds play an extensive role in the oxidative stress signaling pathway in treating OA. Thus, this review summarizes the commonly used natural compounds for treating OA focusing on the oxidative stress signaling pathway and its downstream mediators. Selected databases—such as Scopus, Web of Science, Nature, and PubMed—were used to search for potentially relevant articles. The search is limited to the last 15 years and the search was completed using the Boolean operator’s guideline using the keywords of natural product AND oxidative stress AND osteoarthritis OR natural extract AND ROS AND degenerative arthritis OR natural plant AND free radicals AND degenerative joint disease. In total, 37 articles were selected for further review. Different downstream mechanisms of oxidative stress involved in the usage of natural compounds for OA treatment and anabolic and catabolic effects of natural compounds that exhibit chondroprotective effects have been discussed with the evidence of in vitro and in vivo trials in this review.

Human milk glycosaminoglycans inhibit cytomegalovirus and respiratory syncytial virus infectivity by impairing cell binding

BACKGROUND

The antiviral role of glycosaminoglycans in human milk (HM-GAGs) has been poorly investigated. They are highly sulfated polysaccharides, which were proposed to act as decoy receptors according to their structure. The aim of this study is to evaluate the antiviral potential and the mechanism of action of total and individual HM-GAGs against three pediatric clinically relevant viruses: respiratory syncytial virus (RSV), cytomegalovirus (HCMV), and rotavirus.

METHODS

HM-GAGs were isolated from HM and a library of individual GAGs, structurally related to HM-GAGs, was prepared. The antiviral activity of HM-GAGs and the impact of thermal treatment were investigated in vitro by specific antiviral assays.

RESULTS

We demonstrated that HM-GAGs are endowed with anti-HCMV and anti-RSV activity and that they act by altering virus attachment to cell. We clarified the contribution of individual HM-GAGs, showing a specific structure-related activity. We did not observe any alteration of HM-GAG antiviral activity after thermal treatment.

CONCLUSIONS

We showed that HM-GAGs contribute to the overall antiviral activity of HM, likely exerting a synergic action with other HM antiviral agents. HM-GAGs can now be added to the list of endogenous factors that may reduce breast-milk-acquired HCMV symptomatic infections and protecting infants from respiratory tract infections by RSV.

IMPACT

HM-GAGs have been poorly investigated for their antiviral action so far. We demonstrated that HM-GAGs are endowed with significant anti-HCMV and anti-RSV activity and that they are able to alter virus binding to the cell. The contribution of individual HM-GAGs is mainly exerted by the FMHep and is not based on a simple charge interaction between the virus and sulfate groups but involves a specific GAG structural configuration. Our results contribute to identifying the multiple factors synergically acting in mediating HM antiviral properties and to clarifying their specific mechanism of action.

Preparation and characterization of chondroitin sulfate from large hybrid sturgeon cartilage by hot-pressure and its effects on acceleration of wound healing

In this paper, a combination of hot-pressure, enzymatic hydrolysis and membrane separation process is used for efficiently and environmentally friendly extraction of chondroitin sulfate (CS) from large hybrid sturgeon cartilage, namely, HPCS. The recovery and yield of CS were 93.68% and 36.47% under the optimized conditions. Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and high-performance liquid chromatography (HPLC) indicated that the HPCS was composed of monosulfated disaccharides in position 6 and 4 of the N-acetyl-D-galactosamine (58.38% and 27.34%, respectively) and nonsulfated disaccharide (14.29%), which was similar to the composition of CS extracted by dilute alkali-enzymatic hydrolysis-chemical precipitation from large hybrid sturgeon cartilage (SCS). The wound healing results indicated that HPCS could promote cell migration and proliferation, alleviate inflammation and facilitate angiogenesis, which results in its excellent wound treatment activity. These results provide theoretical and practical significance for the production and application of chondroitin sulfate.

Industrial application of fish cartilaginous tissues

Cartilage is primarily composed of proteoglycans and collagen. Bioactive compounds derived from animal cartilage, such as chondroitin sulfate and type II collagen, have multiple bioactivities and are incorporated in popular health products. The aging population and increases in degenerative and chronic diseases will stimulate the rapid growth of market demand for cartilage products. Commercial production of bioactive compounds primarily involves the cartilages of mammals and poultry. However, these traditional sources are associated zoonosis concerns; thus, cartilage products from the by-products of fish processing has gained increasing attention because of their high level of safety and other activities. In this review, we summarize the current state of research into fish-derived cartilage products and their application, and discuss future trends and tasks to encourage further expansion and exploitation. At present, shark cartilage is the primary source of marine cartilage. However, the number of shark catches is decreasing worldwide, owing to overfishing. This review considers the potential alternative fish cartilage sources for industrialization. Three keys, the sustainable production of fish, new fish-processing model, and market demand, have been discussed for the future realization of efficient fish cartilage use. The industrialization of fish-derived cartilage products is beneficial for achieving sustainable development of local economies and society.

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Bioactive compounds derived from fish cartilage are popular as health products.

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Type II collagen and chondroitin sulfate are the major cartilage bioactive compounds.

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Cartilaginous fishes, sturgeons, and salmonids are potential fish cartilage sources.

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Keys for industrialization are fish production, processing model, and market demands.

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Industrialization of fish cartilage products accords with sustainable development.

Preparation of trypsin-based nanoparticles, colloidal properties and ability to bind bioactive compounds

Nanoparticles (NPs) based on the proteolytic enzyme trypsin (TRY) were prepared by a biocompatible methodology. TRY co-assembled with the anionic polysaccharide chondroitin sulfate (CS) in complexes with well-defined distributions of radii in the range of 100-200 nm by electrostatic complexation at acidic conditions. At pH 7 the complexes were unstable and lost their monomodal size distribution which is potentially related to TRY's weak positive net surface charge and a large negative charge patch that forms at neutral pH. Thermal treatment at conditions which were not expected to interfere with TRY's proteolytic activity was used to stabilize the complexes into NPs that resisted disintegration at pH 7 taking advantage of the ability of the TRY globules to thermally aggregate. The secondary conformation of TRY within the NPs was found fairly unperturbed even after thermal treatment which is crucial for its physiological function. The CS-TRY NPs could bind and encapsulate the bioactive substances curcumin (CUR) and β-carotene (β-C) owing to TRY's hydrophobic domains. The CS-TRY NPs may be considered as a platform for the immobilized active enzyme and multifunctional NPs for hydrophobic bioactive compounds.

Comprehensive analysis of chondroitin sulfate and aggrecan in the head cartilage of bony fishes: Identification of proteoglycans in the head cartilage of sturgeon

Cartilage in the head of sturgeon or salmon has been gaining attention as a rich source of functional chondroitin sulfate (CS) or proteoglycans. Although the cartilage was found in the heads of other bony fishes, the structure of CS and its core protein, especially aggrecan, was not fully investigated. In this study, comprehensive analysis of CS and aggrecan in the head cartilage of 10 bony fishes including sturgeon and salmon was performed. The 4-O-sulfation to 6-O-sulfation ratio (4S/6S ratio; S: sulfate residue) of CS in Perciformes was ≧1.0, while the 4S/6S ratios of CS from sturgeons and salmon were less than 0.5. Dot blotting and proteomic analysis revealed that aggrecan was a major core protein in head cartilage of all bony fishes. These results suggest that the head cartilage of bony fishes is a promising source for the preparation of CS or proteoglycans as a health food ingredient.

Chondroitin sulfate in therapy osteoarthritis chronic pain patients according to actual clinical recommendations

Of undoubted interest is the search for new drugs comparable in effectiveness to nonsteroidal anti-inflammatory drugs (NSAIDs), but with a safer application profile. NSAIDs are characterized by a good analgesic effect due to the modulation of prostaglandin metabolism by inhibition of cyclooxygenase-2. One of the promising directions of pharmacotherapy of degenerative-dystrophic joint lesions is the use of symptom-modifying drugs of delayed action, which include chondroitin sulfate (CS). CS has antiresorptive activity, anti-inflammatory and anti-inflamaging effects. In addition to the direct effect on pain syndrome severity, he also have a modulating level effect of systemic inflammation of cartilage tissue. According to experts of international and Russian societies, pharmaceutical prescription-quality CS is a basic part of the treatment of osteoarthritis. One of the advantages of CS over NSAIDs is the preservation of the effect for 24 months after the treatment. Against the background of the use of CS, it is possible to reduce the dose or completely cancel NSAIDs, which helps to reduce the frequency of adverse events associated with their intake. CS has a favorable safety profile, which is important for elderly patients and those with comorbid diseases (cardioprotective effects). CS drugs can be administered per orally, intramuscularly, intra-articularly and in combination with different administration methods. Several clinical trials of CS (Chondrogard), including randomized, were conducted in Russia. The Russia Health Ministry approved the appointment of parenteral CS in clinical guidelines: Chronic pain in elderly and senile patients (2020), Falls in elderly and senile patients(2020), "Knee osteoarthritis" (2021), "Hip osteoarthritis" (2021).

Substrate specificity of Chondroitinase ABC I based on analyses of biochemical reactions and crystal structures in complex with disaccharides

Chondroitinase ABC I (cABC-I) is the enzyme which cleaves the β-1,4 glycosidic linkage of chondroitin sulfate (CS) by β-elimination. To elucidate more accurately the substrate specificity of cABC-I, we evaluated the kinetic parameters of cABC-I and its reactivity with CS isomers displaying less structural heterogeneity as substrates, e.g., approximately 90 percent of disaccharide units in Chondroitin sulfate A (CSA) or Chondroitin sulfate C (CSC) is D-glucuronic acid and 4-O-sulfated N-acetyl galactosamine (GalNAc) (A-unit) or D-glucuronic acid and 6-O-sulfated GalNAc (C-unit), respectively. cABC-I showed the highest reactivity to CSA and CSC among all CS isomers, and the k_cat/K_m of cABC-I was higher for CSA than for CSC. Next, we determined the crystal structures of cABC-I in complex with CS disaccharides, and analyzed the crystallographic data in combination with molecular docking data. Arg500 interacts with 4-O-sulfated and 6-O-sulfated GalNAc residues. The distance between Arg500 and the 4-O-sulfate group was 0.8 Å shorter than that between Arg500 and the 6-O-sulfated group. Moreover, it is likely that the 6-O-sulfated group is electrostatically repulsed by the nearby Asp490. Thus, we demonstrated that cABC-I has the highest affinity for the CSA richest in 4-O-sulfated GalNAc residues among all CS isomers. Recently, cABC-I was used to treat lumbar disc herniation. The results provide useful information to understand the mechanism of the pharmacological action of cABC-I.

Marine origin materials on biomaterials and advanced therapies to cartilage tissue engineering and regenerative medicine

The body's self-repair capacity is limited, including injuries on articular cartilage zones. Over the past few decades, tissue engineering and regenerative medicine (TERM) has focused its studies on the development of natural biomaterials for clinical applications aiming to overcome this self-therapeutic bottleneck. This review focuses on the development of these biomaterials using compounds and materials from marine sources that are able to be produced in a sustainable way, as an alternative to mammal sources (e.g., collagens) and benefiting from their biological properties, such as biocompatibility, low antigenicity, biodegradability, among others. The structure and composition of the new biomaterials require mimicking the native extracellular matrix (ECM) of articular cartilage tissue. To design an ideal temporary tissue-scaffold, it needs to provide a suitable environment for cell growth (cell attachment, proliferation, and differentiation), towards the regeneration of the damaged tissues. Overall, the purpose of this review is to summarize various marine sources to be used in the development of different tissue-scaffolds with the capability to sustain cells envisaging cartilage tissue engineering, analysing the systems displaying more promising performance, while pointing out current limitations and steps to be given in the near future.

Characterization of chondroitin sulfates isolated from large hybrid sturgeon cartilage and their gastroprotective activity against ethanol-induced gastric ulcers

Sturgeon cartilage, which is rich in chondroitin sulfate (CS), is usually discarded during sturgeon utilization. In this paper, CS was isolated from large hybrid sturgeon skull and backbone and named SCS and BCS, respectively. Their structures were investigated via Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and high performance liquid chromatography (HPLC). The average molecular weights of SCS and BCS were ~ 30-44 kDa. Disaccharide analysis indicated that SCS and BCS had similar chemical structures and were composed of ΔUA-[1 → 3]-GalNAc (ΔDi0S, 14.71%, 16.04%), ΔUA-[1 → 3]-GalNAc-4 s (ΔDi4S, 32.01%, 37.78%) and ΔUA-[1 → 3]-GalNAc-6 s (ΔDi6S, 53.27%, 46.18%). The gastroprotective effect of SCS and BCS were studied using a rat model of ethanol-induced gastric ulcers. Both SCS and BCS had apparent gastroprotective activity and their ulcer inhibition rate reached ~ 35%-45%, which was similar to that of omeprazole (~41%). These results provide useful strategies for the high-value utilization of sturgeon cartilage.

Locomotive syndrome: from paradigms to clinical reality

Locomotive syndrome is an unsatisfactory condition of patients over 60 years of age who need or may require outside help in the near future due to functional deterioration of the musculoskeletal system, including pathology of bone tissue, joints, muscles and nervous tissue. In real clinical practice, one often has to deal with the following manifestations of locomotive syndrome: osteoarthritis, sarcopenia, balance disorders, chronic musculoskeletal pain. Today, there is a clear understanding that drug therapy should be long-term, include comprehensive support for muscle tissue, balance training, and mandatory cognitive-behavioral therapy. Maximum safety of long-term drug therapy can be ensured by the use of vital micronutrients, which include highly purified forms of chondroitin sulfate and glucosamine sulfate, which have a wide range of anti-inflammatory and regenerative effects.

[Chondroitin sulfate role in the complex rehabilitation of elderly people with chronic pain syndrome]

The article presents the data of the latest domestic and foreign original studies, the results of a number of meta-analyses, conclusions of randomized clinical trials (RCTs), and other scientific studies that prove the effectiveness and necessity of mandatory inclusion in the treatment of chronic pain syndrome of the stage of non-invasive non-pharmacological therapy. One of the promising areas of pharmacotherapy for degenerative-dystrophic joint lesions is the use of chondroprotectors (CP), in particular chondroitin sulfate (CS). According to new Clinical Recommendations of Ministry Health (MH) of the Russian Federation (RF) «Chronic pain in patients of elderly and senile age» (2020), according to which the purpose of CS is recommended for patients older than 60 years with joint pain and contraindications to non-steroidal anti-inflammatory drugs (NSAIDs) or senile asthenia for the purpose of pain relief and the prevention of exacerbations of pain. A high level of reliability and persuasiveness of the recommendations was noted (1A) of CS use. Most of the CS is available in the form of forms for oral use, the bioavailability of which, according to clinical studies, is 13-38% due to the destruction of the CS molecules in the gastrointestinal tract. Intramuscular (i/m) administration of the drug can increase the bioavailability of CS, which can not only increase the effectiveness of therapy, but also lead to a more rapid development of the symptomatic effect. In Russia available parenteral forms of CS (Chondroguard) pharmaceutical quality, efficacy has been proven in randomized clinical trial (RCT) MH RF. To relieve pain in the joints, it is recommended to use parenteral forms of CS (Chondroguard) at a dose of 100-200 mg per day, every other day, the total duration of the course of treatment is 25-30 injections.

Research and Application of Chondroitin Sulfate/Dermatan Sulfate-Degrading Enzymes

Chondroitin sulfate (CS) and dermatan sulfate (DS) are widely distributed on the cell surface and in the extracellular matrix in the form of proteoglycan, where they participate in various biological processes. The diverse functions of CS/DS can be mainly attributed to their high structural variability. However, their structural complexity creates a big challenge for structural and functional studies of CS/DS. CS/DS-degrading enzymes with different specific activities are irreplaceable tools that could be used to solve this problem. Depending on the site of action, CS/DS-degrading enzymes can be classified as glycosidic bond-cleaving enzymes and sulfatases from animals and microorganisms. As discussed in this review, a few of the identified enzymes, particularly those from bacteria, have wildly applied to the basic studies and applications of CS/DS, such as disaccharide composition analysis, the preparation of bioactive oligosaccharides, oligosaccharide sequencing, and potential medical application, but these do not fulfill all of the needs in terms of the structural complexity of CS/DS.

A new look at back pain treatment in light of the latest ESCEO guidelines

Chronic pain (CP) is still one of the urgent problems of modern medicine. The paper provides a review of the main pharmacotherapeutic approaches from the standpoint of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO) guidelines. When preparing this material, the authors have analyzed the publications available in the resources: PubMed, EMBASE, Cochrane, and еLIBRARY. The paper presents the main pathogenetic mechanisms of pain syndrome development in osteoarthritis (OA), including synovial inflammation and associated immune disorders. It considers the types of development of pain syndrome and the main prognostic outcomes according the mechanism of pain, providing a rationale for the use of nonsteroidal anti-inflammatory drugs (NSAIDs) and/or chondroprotectors (CPs). In accordance with the ESCEO guidelines, it is noted that when starting OA therapy, CPs should be considered as the first step (in their long-term prescription and pharmaceutical quality), then NSAIDs should be added (topically), then (if ineffective) orally, by excluding patients with hip OA. It is known that the intramuscular administration of CPs (chondroitin sulfate (CS) in particular) can increase their bioavailability. The use of glucosamine sulfate (GS) is recommended for patients over 60 years of age. According to the recommendations of the 2019 ESCEO experts, CS and GS should be used as a disease-modifying OA drug from the first step and at all subsequent stages.

Structural definition of terrestrial chondroitin sulfate of various origin and repeatability of the production process

We report results on the structure, physicochemical characteristics and purity of chondroitin sulfate (CS) samples derived from three largely available and common biological sources such as bovine and porcine trachea and chicken keel bones with the aim to define their structural signatures. Many lots of CS produced by a manufacturer at industrial scale were characterized with a view to assess the reproducibility of the process as not controlled extractive procedures may produce final products with variable structure and biological contaminants as well as not constant clinical efficacy and safety. By using standardized source animal tissues and manufacturing procedure, highly pure CS (∼92 %) products with constant structure and characteristics were obtained. Bovine CS showed a lower molecular weight (MWw of ∼21,500 Da) than porcine (MWw of ∼26,000 Da) and chicken (MWw of ∼35,900 Da) products with a CV% of ∼2.0-7.5 and a polydispersity variability of 0.7-2.7 %. The ratio between the sulfate groups main located in position 4 and 6 of N-acetyl-galactosamine (4/6 ratio) was ∼1.70 for bovine CS versus a value of 3.60 for porcine and ∼2.70 for chicken samples with a overall charge density of 0.92-0.93 and a CV% of 2.1-2.5. The final products also showed the presence of a very low and constant content of other co-purified bio(macro)molecules (hyaluronic acid, keratan sulfate, dermatan sulfate, heparan sulfate, nucleic acids and proteins), calcium and sodium, and the absence of versican. Finally, a high reproducibility of molecular weight values, disaccharide composition, specific optical rotation and particle dimension was observed. The observed parameters are structural signatures useful to specifically identify the origin of CS and obtained by a standardized and highly reproducible manufacturing process. The compositional profile determined from this study provides a measure of the norm and range of variation in CS samples of terrestrial origin produced under standardized production protocol to which future pharmaceutical/nutraceutical final products can be compared. Moreover, the physicochemical properties including molecular weight, disaccharide composition, presence of natural contaminants and particle dimension were characterized to provide the basis of CS of high quality for application as pharmaceutical/nutraceutical active agents.

Short- and Long-Term Effectiveness of Supplementation with Non-Animal Chondroitin Sulphate on Inflammation, Oxidative Stress and Functional Status in Obese Subjects with Moderate Knee Osteoarthritis before and after Physical Stress: A Randomized, Double-Blind, Placebo-Controlled Trial

It has recently been demonstrated that chronic supplementation with nonanimal chondroitin sulfate (nonanimal CS) in overweight subjects with knee osteoarthritis (OA) improves the function, pain and inflammation, but there are no studies of its effectiveness in an acute setting. In 48 obese subjects with moderate knee OA, we investigated the effectiveness of nonanimal CS supplementation for eight weeks on the inflammation, functional status, oxidative stress, cartilage catabolism markers, metabolic profile and body composition, by Dual-Energy X-ray Absorptiometry (DXA) at the baseline, after 15 days and at the end of the eight-week study. To evaluate the acute effectiveness on inflammation, 15-min cycle training sessions were done 15 days after the start of the study and at the end. C-reactive protein (CRP) was assayed in blood samples collected before and after the two cycling exercises. The 48 obese subjects (M and F, 20–50 years, body mass index (BMI) 30–35 kg/m²) were randomly assigned to an experimental group (N = 24, 600-mg tablet of nonanimal CS/day) or the control group (N = 24, placebo). The between-groups analysis of covariance showed a significant effect on the Western Ontario and McMaster Universities Arthritis index (WOMAC) scale (p = 0.000) and CRP (p = 0.022). For intra-group differences, the result was significant in the CS group for BMI, WOMAC, CRP, total cholesterol and Homeostasis Model Assessment (HOMA). In these obese adults with OA, nonanimal CS improved the inflammation, knee function, metabolic profile and body composition.

Fourier-transformed infrared spectroscopy, physicochemical and biochemical properties of chondroitin sulfate and glucosamine as supporting information on quality control of raw materials

Background

Chondroitin sulfate (CS) and glucosamine (GLcN) are recommended for the restoration of the articular cartilage surface in patients affected by osteoarthritis. They are commercialized as pharmaceutical-grade products and as food supplements, and there are reports that they do not undergo the strict quality controls of pharmaceuticals. Herein, we evaluated the physicochemical parameters of two raw materials (CS and GlcN) obtained from two distinct suppliers in Brazil and compare the obtained data with the product specification provided by the manufacturer. Also, the homogeneity and purity grade of samples were analyzed by FT-IR spectroscopy.

Results

The organoleptic properties and solubility of CS and GlcN samples obtained from pharmacy analyses and the supplier’s specifications are in accordance with the standards required by the Brazilian Health Regulatory Agency (ANVISA). However, the intraclass correlation coefficient (ICC) and Bland Altman analysis of pH and the density values of samples are statistically different between the suppliers. In addition, FT-IR analyses indicated that there is non-homogeneity in the CS and GlcN samples tested, showing that both manufacturers distribute the drugs in different concentrations, although both declare the same concentration in the product technical specifications.

Conclusion

In summary, our study demonstrated that physicochemical parameters are insufficient to ensure product quality, and it is necessary to implement a more efficient protocol to ensure the quality of the final product.

Graphical abstract

Molecular Changes in Dengue Envelope Protein Domain III upon Interaction with Glycosaminoglycans

Dengue fever is a rapidly emerging vector-borne viral disease with a growing global burden of approximately 390 million new infections per annum. The Dengue virus (DENV) is a flavivirus spread by female mosquitos of the aedes genus, but the mechanism of viral endocytosis is poorly understood at a molecular level, preventing the development of effective transmission blocking vaccines (TBVs). Recently, glycosaminoglycans (GAGs) have been identified as playing a role during initial viral attachment through interaction with the third domain of the viral envelope protein (EDIII). Here, we report a systematic study investigating the effect of a range of biologically relevant GAGs on the structure and oligomeric state of recombinantly generated EDIII. We provide novel in situ biophysical evidence that heparin and chondroitin sulphate C induce conformational changes in EDIII at the secondary structure level. Furthermore, we report the ability of chondroitin sulphate C to bind EDIII and induce higher-order dynamic molecular changes at the tertiary and quaternary structure levels which are dependent on pH, GAG species, and the GAG sulphation state. Lastly, we conducted ab initio modelling of Small Angle Neutron Scattering (SANS) data to visualise the induced oligomeric state of EDIII caused by interaction with chondroitin sulphate C, which may aid in TBV development.

Current Research Landscape of Marine-Derived Anti-Atherosclerotic Substances

Atherosclerosis is a chronic disease characterized by lipid accumulation and chronic inflammation of the arterial wall, which is the pathological basis for coronary heart disease, cerebrovascular disease and thromboembolic disease. Currently, there is a lack of low-cost therapeutic agents that effectively slow the progression of atherosclerosis. Therefore, the development of new drugs is urgently needed. The research and development of marine-derived drugs have gained increasing interest from researchers across the world. Many marine organisms provide a rich material basis for the development of atherosclerotic drugs. This review focuses on the latest technological advances in the structures and mechanisms of action of marine-derived anti-atherosclerotic substances and the challenges of the application of these substances including marine polysaccharides, proteins and peptides, polyunsaturated fatty acids and small molecule compounds. Here, we describe the theoretical basis of marine biological resources in the treatment of atherosclerosis.

A Novel Splice Variant of HYAL-4 Drives Malignant Transformation and Predicts Outcome in Patients with Bladder Cancer

PURPOSE

Poor prognosis of patients with muscle-invasive bladder cancer that often metastasizes drives the need for discovery of molecular determinants of bladder cancer progression. Chondroitin sulfate proteoglycans, including CD44, regulate cancer progression; however, the identity of a chondroitinase (Chase) that cleaves chondroitin sulfate from proteoglycans is unknown. HYAL-4 is an understudied gene suspected to encode a Chase, with no known biological function. We evaluated HYAL-4 expression and its role in bladder cancer.

EXPERIMENTAL DESIGN

In clinical specimens, HYAL-4 wild-type (Wt) and V1 expression was evaluated by RT-qPCR, IHC, and/or immunoblotting; a novel assay measured Chase activity. Wt and V1 were stably expressed or silenced in normal urothelial and three bladder cancer cell lines. Transfectants were analyzed for stem cell phenotype, invasive signature and tumorigenesis, and metastasis in four xenograft models, including orthotopic bladder.

RESULTS

HYAL-4 expression, specifically a novel splice variant (V1), was elevated in bladder tumors; Wt expression was barely detectable. V1 encoded a truncated 349 amino acid protein that was secreted. In bladder cancer tissues, V1 levels associated with metastasis and cancer-specific survival with high efficacy and encoded Chase activity. V1 cleaved chondroitin-6-sulfate from CD44, increasing CD44 secretion. V1 induced stem cell phenotype, motility/invasion, and an invasive signature. CD44 knockdown abrogated these phenotypes. V1-expressing urothelial cells developed angiogenic, muscle-invasive tumors. V1-expressing bladder cancer cells formed tumors at low density and formed metastatic bladder tumors when implanted orthotopically.

CONCLUSIONS

Our study discovered the first naturally-occurring eukaryotic/human Chase and connected it to disease pathology, specifically cancer. V1-Chase is a driver of malignant bladder cancer and potential predictor of outcome in patients with bladder cancer.

Hyaluronic acid and Chondroitin sulfate from marine and terrestrial sources: Extraction and purification methods

Hyaluronic acid (HA) and chondroitin sulfate (CS) are valuable bioactive polysaccharides that have been highly used in biomedical and pharmaceutical applications. Extensive research was done to ensure their efficient extraction from marine and terrestrial by-products at a high yield and purity, using specific techniques to isolate and purify them. In general, the cartilage is the most common source for CS, while the vitreous humor is main used source of HA. The developed methods were based in general on tissue hydrolysis, removal of proteins and purification of the target biopolymers. They differ in the extraction conditions, enzymes and/or solvents used and the purification technique. This leads to specific purity, molecular weight and sulfation pattern of the isolated HA and CS. This review focuses on the analysis and comparison of different extraction and purification methods developed to isolate these valuable biopolymers from marine and terrestrial animal by-products.

Glycosaminoglycans from Co-Products of «Scyliorhinus canicula»: Extraction and Purification in Reference to the European Pharmacopoeia Requirement

Background

Glycosaminoglycans (GAGs), including hyaluronic acid (HA), dermatan sulfate (DS) and chondroitin sulfate (CS) are essential components of the bone and cartilage tissues. CS isolated from the cartilage tissue of various animals has found application in pharmaceuticals, cosmetics and food industries. In the first part of the present work, three methods were used and compared to extract and purify glycosaminoglycans (GAGs) from the cartilage powder of a local cartilaginous marine species «Scyliorhinus canicula». One of these GAGs, chondroitin sulfate (CS), will be exploited for the development of an anti-osteoarthritis generic at the request of a collaborative pharmaceutical industry. Thus this active ingredient must meet the requirements and tests described by the European Pharmacopoeia (Ph. Eur.). These tests are treated in the second part of this work.

Results

Among the three methods that have been applied in the present work, in order to optimize the best process for GAGs preparation, enzymatic hydrolysis with papain followed by deproteinisation using trichloroacetic acid (TCA) was found the best one. The separation of the extracted GAGs using agarose gel electrophoresis, and the identification of bands by Fourier Transform Infrared (FT-IR) Spectroscopy, revealed that the cartilage GAGs of « Scyliorhinus canicula» are exclusively chondroitin sulfate (CS) and dermatane sulfate (DS), with proportions of 12.889 and 87.111% respectively, and that CS is of type C. The extraction technique with papain provides a product with GAGs content of around 90%. The TCA deproteinisation yielded the lowest level of protein (2.8%) in the extracted GAGs, less than 3%, which is the standard required by the European Pharmacopoeia (Ph. Eur.).Cetylpyridinium chloride (CPC) assay suggests that the titration technique, although is introduced by the Ph. Eur. for the determination of CS content, is not an accurate method, and that the values obtained by the optimized and validated HPLC method, described in this work, are more exact.

Conclusion

The extracted and purified active ingredient is perfectly conform to the tests described by the Ph. Eur. The results suggest that the co-product of Scyliorhinus canicula would be a perfect source of molecules of pharmacological interest, obtained by a simple and non-agressive process.

Thermodynamic profiles of the interactions of suramin, chondroitin sulfate, and pentosan polysulfate with the inhibitory domain of TIMP-3

Extracellular levels of soluble TIMP-3 are low, reflecting its binding by extracellular matrix (ECM) components including sulfated glycosaminoglycans (SGAGs) and endocytosis via low density lipoprotein receptor-related protein 1. Since TIMP-3 inhibits ECM degradation, the ability of SGAGs to elevate extracellular TIMP-3 is significant for osteoarthritis treatment. Previous studies of such interactions have utilized immobilized TIMP-3 or ligands. Here, we report the thermodynamics of the interactions of the sGAG-binding N-domain of TIMP-3 with chondroitin sulfate, pentosan polysulfate, and suramin in solution using isothermal titration calorimetry. All three interactions are driven by a favorable negative enthalpy change combined with an unfavorable decrease in entropy. The heat capacity changes (ΔC_p ) for all of the interactions are zero, indicating an insignificant contribution from hydrophobic interactions.

Purification, compositional analysis, and anticoagulant capacity of chondroitin sulfate/dermatan sulfate from bone of corb (Sciaena umbra)

Chondroitin sulfate/dermatan sulfate (CS/DS) were isolated and purified for the first time from the bone of corb (Sciaena umbra) (CBG) and their chemical composition and anticoagulant activity were assessed. Infrared spectrum and agarose-gel electrophoresis for extracted CS/DS were also investigated. The results showed that the purified CS/DS obtained at a yield of 10% contains about 31.28% sulfate and an average molecular mass of 23.35 kDa. Disaccharide analysis indicated that CBG was composed of monosulfated disaccharides in positions 6 and 4 of the N-acetylgalactosamine (8.6% and 40.0%, respectively) and disulfated disaccharides in different percentages. The charge density was 1.4 and the ratio of 4:6 sulfated residues was equal to 4.64. Chondroitinase AC showed that the purified CS/DS contained mainly 74% CS and 26% DS. Moreover, the new CS/DS extracted from bone of corb showed a strong anticoagulant effect through activated partial thrombosis time (aPTT), thrombin time (TT) and prothrombin time (PT). In fact, CBG prolonged significantly (p < 0.05), aPTT and PT about 2.62 and 1.26 fold, respectively, greater than that of the negative control at a concentration of 1000 μg/mL. However, TT assay of CBG was prolonged 3.53 fold compared with the control at 100 μg/mL. The purified CS/DS displayed a promising anticoagulant potential, which may be used as a novel and soothing drug.

Investigation of glycosaminoglycan mimetic scaffolds for neurite growth

Spinal cord injury can lead to severe dysfunction as a result of limited nerve regeneration that is due to an inhibitory environment created at the site of injury. Neural tissue engineering using materials that closely mimic the extracellular matrix (ECM) during neural development could enhance neural regeneration. Glycosaminoglycans (GAGs), which are sulfated polysaccharides, have been shown to modulate axonal outgrowth in neural tissue depending upon the position and degree of sulfation. Cellulose sulfate (CelS), which is a GAG mimetic, was evaluated for its use in promoting neurite extension. Aligned fibrous scaffolds containing gelatin blended with 0.25% partially sulfated cellulose sulfate (pCelS), having sulfate predominantly at the 6-carbon position of the glucose monomer unit, and fully sulfated cellulose sulfate (fCelS), which is sulfated at the 2-, 3-, and 6-carbon positions of the glucose monomer unit, were fabricated using the electrospinning method. Comparisons were made with scaffolds containing native GAGs, chondroitin sulfate-A (CS-A) and chondroitin sulfate-C (CS-C), which were obtained from commercial sources. CS-A and CS-C are present in neural tissue ECM. The degree of sulfation and position of sulfate groups was determined using elemental analysis, Fourier-transform infrared spectroscopy (FTIR), Raman microspectroscopy, and ¹³C nuclear magnetic resonance (NMR). In vitro studies examined both nerve growth factor (NGF) binding on scaffolds and neurite extension by dorsal root ganglion (DRG) neurons. NGF binding was highest on scaffolds containing pCelS and fCelS. Neurite extension was greatest for scaffolds containing fCelS followed by pCelS, with the lowest outgrowth on the CS-A containing scaffolds, suggesting that the degree and position of sulfation of CelS was permissible for neurite outgrowth. This study demonstrated that cellulose sulfate, as a GAG mimetic, could be used for future neural tissue regeneration application. STATEMENT OF SIGNFICANCE: Scaffolds that closely mimic the native extracellular matrix (ECM) during development may be a promising approach to enhance neural regeneration. Here, we reported a glycosaminoglycan (GAG) mimetic derived from cellulose that promotes neurite extension over native GAGs, chondroitin sulfate-A (CS-A) and chondroitin sulfate-C (CS-C), which are present in neural ECM. Depending upon the degree and position of sulfation, the GAG mimetic can impact nerve growth factor binding and permissive neurite outgrowth.

Chondroitin Sulfate Safety and Quality

The industrial production of chondroitin sulfate (CS) uses animal tissue sources as raw material derived from different terrestrial or marine species of animals. CS possesses a heterogeneous structure and physical-chemical profile in different species and tissues, responsible for the various and more specialized functions of these macromolecules. Moreover, mixes of different animal tissues and sources are possible, producing a CS final product having varied characteristics and not well identified profile, influencing oral absorption and activity. Finally, different extraction and purification processes may introduce further modifications of the CS structural characteristics and properties and may lead to extracts having a variable grade of purity, limited biological effects, presence of contaminants causing problems of safety and reproducibility along with not surely identified origin. These aspects pose a serious problem for the final consumers of the pharmaceutical or nutraceutical products mainly related to the traceability of CS and to the declaration of the real origin of the active ingredient and its content. In this review, specific, sensitive and validated analytical quality controls such as electrophoresis, eHPLC (enzymatic HPLC) and HPSEC (high-performance size-exclusion chromatography) able to assure CS quality and origin are illustrated and discussed.

Chondroitin Sulfate-Degrading Enzymes as Tools for the Development of New Pharmaceuticals

Chondroitin sulfates are linear anionic sulfated polysaccharides found in biological tissues, mainly within the extracellular matrix, which are degraded and altered by specific lyases depending on specific time points. These polysaccharides have recently acquired relevance in the pharmaceutical industry due to their interesting therapeutic applications. As a consequence, chondroitin sulfate (CS) lyases have been widely investigated as tools for the development of new pharmaceuticals based on these polysaccharides. This review focuses on the major breakthrough represented by chondroitin sulfate-degrading enzymes and their structures and mechanisms of function in addition to their major applications.

Liquefaction of chicken sternal cartilage by steam explosion to isolate chondroitin sulfate

Chondroitin sulfate (CS), together with peptide, was isolated from the liquid fraction of chicken sternal cartilage subjected to steam explosion (SE) by membrane separation. Cartilage was liquefied via the SE conditions, including various pressures (1.0-1.6 MPa) and times (60-140 s). The extraction procedure was optimized as follows: the amount of papain added, 0.11%; enzymolysis time, 10.5 h; and enzymolysis temperature, 56.5 °C, under which the highest recovery and total yield of CS were 92.15% and 18.55% at 1.4 MPa for120 s, and the counterparts of peptides were 87.35% (1.0 MPa, 140 s) and 63.07% (1.6 MPa, 140 s). The average molecular weight of CS samples ranged from 30 to 35 kDa. CS sample was confirmed using agarose-gel electrophoresis, and the structure was analysed Fourier transform infrared spectroscopy, chromatography and nuclear magnetic resonance. Taken together, SE can be an eco-friendly pretreatment method to liquefy cartilage for CS isolation.

Chicken leg bone as a source of chondroitin sulfate

In this work, chondroitin sulfate (CS) was extracted from chicken leg bone soup using the heat-resin static adsorption extraction (HSAE) method. The HSAE method was optimized as follows: resin dosage, 10%; adsorption time, 4.3 h; eluent concentration, 2 M; eluent time, 1.3 h, under which the yield of CS1 from the bone soup reached 0.14% and the recovery rate was 67.35%. CS2, as reference, was obtained from the ends of chicken leg bone using enzymatic method. CS1 and CS2, together with other glycosaminoglycans, were confirmed using agarose-gel electrophoresis. The average molecular weight of CS1 and CS2 was 35.81 kDa and 37.18 kDa, respectively. The structures of CS1 and CS2 were compared using Fourier-transform infrared spectroscopy and high-performance liquid chromatography, and no significant difference was observed. Overall, the HSAE method was proposed to be a promising approach for the coproduction of CS and bone soup.