Oral bioavailability of chondroitin sulfate (Condrosulf) and its constituents in healthy male volunteers

Bacteroides salyersiae is a potent chondroitin sulfate-degrading species in the human gut microbiota

Chondroitin sulfate (CS) has widely been used as a symptomatic slow-acting drug or a dietary supplement for the treatment and prevention of osteoarthritis. However, CS could not be absorbed after oral intake due to its polyanionic nature and large molecular weight. Gut microbiota has recently been proposed to play a pivotal role in the metabolism of drugs and nutrients. Nonetheless, how CS is degraded by the human gut microbiota has not been fully characterized. In the present study, we demonstrated that each human gut microbiota was characterized with a unique capability for CS degradation. Degradation and fermentation of CS by the human gut microbiota produced significant amounts of unsaturated CS oligosaccharides (CSOSs) and short-chain fatty acids. To uncover which microbes were responsible for CS degradation, we isolated a total of 586 bacterial strains with a potential CS-degrading capability from 23 human fecal samples. Bacteroides salyersiae was a potent species for CS degradation in the human gut microbiota and produced the highest amount of CSOSs as compared to other well-recognized CS-degraders, including Bacteroides finegoldii, Bacteroides thetaiotaomicron, Bacteroides xylanisolvens, and Bacteroides ovatus. Genomic analysis suggested that B. salyersiae was armed with multiple carbohydrate-active enzymes that could potentially degrade CS into CSOSs. By using a spent medium assay, we further demonstrated that the unsaturated tetrasaccharide (udp4) produced by the primary degrader B. salyersiae could serve as a "public goods" molecule for the growth of Bacteroides stercoris, a secondary CS-degrader that was proficient at fermenting CSOSs but not CS. Taken together, our study provides insights into the metabolism of CS by the human gut microbiota, which has promising implications for the development of medical and nutritional therapies for osteoarthritis. Video Abstract.

Orally administered low-molecular weight agaro-oligosaccharides are absorbed into the plasma of healthy humans

Agaro-oligosaccharides (AOSs) are known to have biological activities, such as anti-inflammatory, anti-tumor, and anti-obesity effects. Although existing evidence suggests the presence of AOSs in peripheral tissues after oral administration, whether AOSs permeate into the blood circulation remains unknown. Thus, we hypothesized that AOSs with low-molecular weight can permeate the human gastrointestinal tract. To test this hypothesis, the time course of absorption was examined by analyzing plasma samples before and 1, 2, and 4 h after ingestion. Analysis was performed using liquid chromatography/mass spectrometry after labeling with p-aminobenzoic ethyl ester. Our results showed that the plasma concentration of agarobiose (Abi) was higher than that of agarotetraose (Ate); however, agarohexaose was not detected. Additionally, plasma levels of Abi and Ate were proportional to the dose. These results suggest that permeation efficiency is dependent on the molecular weight and that the systemic absorption of Abi via the gastrointestinal tract is better than that of Ate. These findings will contribute to a better understanding of the bioactivity of orally administered AOSs in peripheral tissues.

Oral supplementation with fish cartilage hydrolysate in an adult population suffering from knee pain and function discomfort: results from an innovative approach combining an exploratory clinical study and an ex vivo clinical investigation

BACKGROUND

Aging is frequently associated with impairments of the musculoskeletal system and many elderly people experience joint discomfort or pain which might reduce their ability to move and consequently alter their quality of life. A beneficial effect of fish cartilage hydrolysate (FCH) on pain and joint function has recently been shown in an ACLT/pMMx osteoarthritis rat model.

METHODS

We therefore performed an exploratory, non-comparative, multi-centric clinical trial including 33 subjects with moderate knee joint discomfort and loss of functionality to investigate the efficacy of FCH on their algo-functional status. We further determined the potential health benefit of FCH in an original clinical ex vivo study investigating the role of FCH human metabolites on primary human chondrocytes.

RESULTS

FCH significantly improved knee pain and function, as assessed by the Knee injury and Osteoarthritis Outcome Score (KOOS). Moreover, FCH significantly reduced pain at rest and while walking, and patient global assessment (PGA), as assessed by the Visual Analogue Scale (VAS), and improved patients' quality of life (SF-36). FCH metabolites decreased the synthesis of catabolic factors (MMP-13) and pro-inflammatory mediators (NO, PGE2) and limited the inhibitory effect of IL-1β on the synthesis of cartilage matrix components (GAG and collagen).

CONCLUSIONS

Thus, these data provide insights on the mode of action of FCH in humans and contribute to explain how FCH may relieve pain and improve joint function in subjects with knee discomfort. Although these preliminary data need to be confirmed in a randomized controlled trial, they strongly support the potential health benefit of such an active ingredient.

TRIAL REGISTRATION

The study was registered on clinicaltrials.gov with the identifier NCT04420091 (09/06/2020).

Anti-aging biomaterial sturgeon chondroitin sulfate upregulating anti-oxidant and SIRT-1/c-fos gene expression to reprogram stem cell senescence and prolong longevity

Aging involves tissue and cell potential dysfunction characterized by stem cell senescence and extracellular matrix microenvironment (ECM) alteration. Chondroitin sulfate (CS), found in the ECM of normal cells and tissues, aids in maintaining tissue homeostasis. Here, CS-derived biomaterial (CSDB) from sturgeon is extracted to investigate its antiaging effect in senescence-accelerated mouse prone-8 (SAMP8) mice and elucidate the underlying mechanism of its action. Although CSDB has been widely extracted from different sources and used as a scaffold, hydrogel, or drug carrier for the treatment of various pathological diseases, CSDB has not yet been used as a biomaterial for the amelioration of senescence and aging features. In this study, the extracted sturgeon CSDB showed a low molecular weight and comprised 59% 4-sulfated CS and 23% 6-sulfated CS. In an in vitro study, sturgeon CSDB promoted cell proliferation and reduced oxidative stress to inhibit stem cell senescence. In an ex vivo study, after oral CSDB treatment of SAMP8 mice, the stem cells were extracted to analyze the p16Ink4a and p19Arf gene-related pathways, which were inhibited and then SIRT-1 gene expression was upregulated to reprogram stem cells from a senescence state for retarding aging. In an in vivo study, CSDB also restored the aging-phenotype-related bone mineral density and skin morphology to prolong longevity. Thus, sturgeon CSDB may be useful for prolonging healthy longevity as an anti-aging drug.

Molecular weight and gut microbiota determine the bioavailability of orally administered hyaluronic acid

The ability of hyaluronan as a dietary supplement to increase skin moisture and relieve knee pain has been demonstrated in several clinical studies. To understand the mechanism of action, determining hyaluronan's bioavailability and in vivo fate is crucial. Here, we used ¹³C-hyaluronan combined with LC-MS analysis to compare the absorption and metabolism of oral hyaluronan in germ-free and conventional wild-type mice. The presence of Bacteroides spp. in the gut was crucial for hyaluronan absorption. Specific microorganisms cleave hyaluronan into unsaturated oligosaccharides (<3 kDa) which are partially absorbed through the intestinal wall. The remaining hyaluronan fragments are metabolized into short-chain fatty acids, which are only metabolites available to the host. The poor bioavailability (~0.2 %) of oral hyaluronan indicates that the mechanism of action is the result of the systematic regulatory function of hyaluronan or its metabolites rather than the direct effects of hyaluronan at distal sites of action (skin, joints).

Polysaccharide-Based Nanomedicines Targeting Lung Cancer

A primary illness that accounts for a significant portion of fatalities worldwide is cancer. Among the main malignancies, lung cancer is recognised as the most chronic kind of cancer around the globe. Radiation treatment, surgery, and chemotherapy are some medical procedures used in the traditional care of lung cancer. However, these methods lack selectivity and damage nearby healthy cells. Several polysaccharide-based nanomaterials have been created to transport chemotherapeutics to reduce harmful and adverse side effects and improve response during anti-tumour reactions. To address these drawbacks, a class of naturally occurring polymers called polysaccharides have special physical, chemical, and biological characteristics. They can interact with the immune system to induce a better immunological response. Furthermore, because of the flexibility of their structures, it is possible to create multifunctional nanocomposites with excellent stability and bioavailability for the delivery of medicines to tumour tissues. This study seeks to present new views on the use of polysaccharide-based chemotherapeutics and to highlight current developments in polysaccharide-based nanomedicines for lung cancer.

Benefits of Circulating Human Metabolites from Fish Cartilage Hydrolysate on Primary Human Dermal Fibroblasts, an Ex Vivo Clinical Investigation for Skin Health Applications

Due to its significant exposure to stressful environmental factors, the skin undergoes a high remodeling rate over time, which alters not only its appearance but also its functionality. This alteration of the skin, namely photoaging, is characterized by dryness and a loss of elasticity that mainly originates from the dysregulation of dermal fibroblast activities. In order to overcome such tissue outcome, cosmetic products have evolved toward nutricosmetics, thus promoting beauty from within. Among bio-actives of interest, bio-peptides deriving from plant or animal sources may exert various biological activities beyond their nutritional value. However, studies remain mostly descriptive and the mode of action at the cellular level in clinic remains a concern. In a recent clinical trial, it was showed that supplementation with a fish cartilage hydrolysate (FCH) improved signs of chronological and photoaging-induced skin changes in healthy women. Here, using an original ex vivo clinical approach adapted to nutricosmetic purpose, we further demonstrated that this fish cartilage hydrolysate was absorbed and that the circulating metabolites produced in humans following FCH intake stimulate human dermal fibroblast growth, promote specific hyaluronan production, up-regulate elastin synthesis and inhibit MMP-1 and 3 expression along with the enhancement of TGF-β release. Altogether, these data provide clues on the mechanisms likely contributing to the beneficial impact of FCH on human skin functionality by supporting hydration, elasticity and limiting the expression of catabolic factors involved in photoaging onset.

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.

Structural analysis and anti-cancer activity of low-molecular-weight chondroitin sulfate from hybrid sturgeon cartilage

Low-molecular-weight chondroitin sulfate (CS) has attracted widespread attention due to its better bioavailability and bioactivity than native CS. In this study, a low-molecular-weight CS (named SCS-F2) was prepared from hybrid sturgeon (Acipenser schrenckii × Huso dauricus) cartilage by enzymatic depolymerization with high in vitro absorption and anti-cancer activity. The structure of SCS-F2 was characterized and the in vivo biodistribution and colorectal cancer prevention effect was investigated. The results revealed that SCS-F2 consisted of 48.84% ΔDi-6S [GlcUAβ1-3GalNAc(6S)], 32.11% ΔDi-4S [GlcUAβ1-3GalNAc(4S)], 16.05% ΔDi-2S,6S [GlcUA(2S)β1-3GalNAc(6S)] and 3.0% ΔDi-0S [GlcUAβ1-3GalNAc]. Animal study showed that the SCS-F2 could be effectively absorbed and delivered to the tumor site and significantly prevented the growth of HT-29 xenograft by inhibiting cell proliferation and inducing apoptosis without showing any negative effect to normal tissues. Therefore, SCS-F2 could be developed as a potential nutraceutical to protect against colorectal cancer.

Drug Screening Implicates Chondroitin Sulfate as a Potential Longevity Pill

Discovering compounds that promote health during aging ("geroprotectors") is key to the retardation of age-related pathologies and the prevention of chronic age-related diseases. In in-silico and model organisms' lifespan screens, chondroitin sulfate has emerged as a geroprotective compound. Chondroitin sulfate is a glycosaminoglycan attached to extracellular matrix proteins and is naturally produced by our body. Oral supplementation of chondroitin sulfate shows a high tolerance in humans, preferable pharmacokinetics, a positive correlation with healthy human longevity, and efficacy in deceleration of age-related diseases in randomized clinical trials. We have recently shown that chondroitin sulfate supplementation increases the lifespan of C. elegans. Thus, chondroitin sulfate holds the potential to become a geroprotective strategy to promote health during human aging. This review discusses the two major potential mechanisms of action, extracellular matrix homeostasis and inhibition of inflammation, that counteract age-related pathologies upon chondroitin sulfate supplementation.

Oral Delivery of Parathyroid Hormone Using a Triple-Padlock Nanocarrier for Osteoporosis via an Enterohepatic Circulation Pathway

Intermittent subcutaneous (S.C.) injection of teriparatide [PTH (1-34)] is one of the effective therapies to cure osteoporosis. However, a long-term repeated administration of teriparatide by S.C. to the patients is highly challenging. Herein, a triple padlock nanocarrier prepared by a taurocholic acid-conjugated chondroitin sulfate A (TCSA) is designed to develop an oral dosage form of recombinant human teriparatide (rhPTH). Oral administration of TCSA/rhPTH to the bilateral ovariectomized (OVX) rats resulted in the recovery of the bone marrow density and healthy serum bone parameters from the severe osteoporotic conditions. Also, it enhanced new bone formation in the osteoporotic tibias. This triple padlock oral delivery platform overcame the current barriers associated with teriparatide administration and exhibited a promising therapeutic effect against osteoporosis.

Topical Application of Peptide-Chondroitin Sulfate Nanoparticles Allows Efficient Photoprotection in Skin

In this article, we describe a method of delivery of chondroitin sulfate to skin as nanoparticles and demonstrate its anti-inflammatory and antioxidant role using UV irradiation as a model condition. These nanoparticles, formed through electrostatic interactions of chondroitin sulfate with a skin-penetrating peptide, were found to be homogenous with positive surface charges and stable at physiological and acidic pH under certain conditions. They were able to enter into the human keratinocyte cell line (HaCaT), artificial skin membrane (mimicking the human skin), and mouse skin tissue unlike free chondroitin sulfate. The preapplication of nanoparticles also exhibited reduced levels of oxidative stress, cyclobutane pyrimidine dimer formation, TNF-α, and so on in UV-B-irradiated HaCaT cells. In an acute UV-B irradiation mouse model, their topical application resulted in reduced epidermal thickness and sunburn cells, unlike in the case of free chondroitin sulfate. Thus, a completely noninvasive method was used to deliver a bio-macromolecule into the skin without using injections or abrasive procedures.

Highly purified chondroitin sulfate: a literature review on clinical efficacy and pharmacoeconomic aspects in osteoarthritis treatment

Osteoarthritis (OA) is the most prevalent musculoskeletal disease and a major cause of negative relevant outcomes, associated with an ever-increasing societal burden. Pharmaceutical-grade chondroitin sulfate (CS) was repeatedly reported to reduce pain and improve function in patients with OA. This article aims to review the evidence for the role of highly purified (hp) CS (Condrosulf^®, IBSA) in the treatment of OA. We collected and reported evidence concerning (1) efficacy of hpCS 800 mg/day in the treatment of OA affecting the knee, hand and hip; (2) efficacy and safety of hpCS 1200 mg/day also in the oral gel formulation; (3) the safety profile of hpCS; (4) the difference of hpCS and pharmaceutical-grade formulations versus food supplements; (5) pharmacoeconomic added value of hpCS. The data support that hpCS is an effective and safe treatment of OA, with its effect already evident at 30 days; in addition, its beneficial action is prolonged, being maintained for at least 3 months after the drug is discontinued. Full safety reports’ analyses confirm that CS is safe to use and has almost no side effects, in particular, it showed better gastrointestinal tolerance if compared with non-steroidal anti-inflammatory drugs (NSAIDs). Moreover, the therapeutic strategy has proved to be cost-effective: treatment with CS reduced the use of NSAIDs and their side effects.

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.

Enzymatic Synthesis of Glycans and Glycoconjugates

Glycoconjugates have great potential to improve human health in a multitude of different ways and fields. Prominent examples are human milk oligosaccharides and glycosaminoglycans. The typical choice for the production of homogeneous glycoconjugates is enzymatic synthesis. Through the availability of expression and purification protocols, recombinant Leloir glycosyltransferases are widely applied as catalysts for the synthesis of a wide range of glycoconjugates. Extensive utilization of these enzymes also depends on the availability of activated sugars as building blocks. Multi-enzyme cascades have proven a versatile technique to synthesize and in situ regenerate nucleotide sugar.In this chapter, the functions and mechanisms of Leloir glycosyltransferases are revisited, and the advantage of prokaryotic sources and production systems is discussed. Moreover, in vivo and in vitro pathways for the synthesis of nucleotide sugar are reviewed. In the second part, recent and prominent examples of the application of Leloir glycosyltransferase are given, i.e., the synthesis of glycosaminoglycans, glycoconjugate vaccines, and human milk oligosaccharides as well as the re-glycosylation of biopharmaceuticals, and the status of automated glycan assembly is revisited.

Lentinan Inhibits AGE-Induced Inflammation and the Expression of Matrix-Degrading Enzymes in Human Chondrocytes

Background

Chondrocyte-mediated inflammation is an important pathological component of osteoarthritis (OA) development. There are currently no therapies that completely reverse the development of OA. Lentinan, a type of polysaccharide derived from Lentinus edodes, has been demonstrated to possess significant anti-viral, anti-cancer, and anti-inflammatory effects, and has been recently used in the treatment of several inflammatory diseases. However, little research has focused on the pharmacological effect of lentinan in human OA.

Materials and Methods

We evaluated the anti-inflammatory and anti-ROS effects of lentinan in SW1353 chondrocytes treated with AGEs using real-time polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and the nitro oxide-specific stain DAF-FM DA. The regulatory effects of lentinan on NF-κB and MAPK p38 signaling were investigated via promoter assay and Western blot analysis.

Results

We found that lentinan inhibits the production of pro-inflammatory cytokines, including IL-1β, TNF-α, IL-8 and the secretion of PGE₂ and NO, by reducing the expression of COX-2 and iNOS in AGE-challenged chondrocytes. Lentinan also reduces AGE-induced increased expression of matrix metalloproteinases-1, −3, and −13 (MMP-1, MMP-3, MMP-13). Furthermore, lentinan has a similar effect on a disintegrin and metalloproteinase with thrombospondin motifs-4 and −5 (ADAMTS-4, ADAMTS-5). Mechanistically, lentinan reduces the activation of NF-κB.

Conclusion

Our findings indicate that lentinan shows a protective effect against AGE-induced inflammatory response in chondrocytes. These findings suggest that lentinan is a promising agent for the treatment of OA that could be used as a dietary supplement for patients with OA.

Integral Roles of Specific Proteoglycans in Hair Growth and Hair Loss: Mechanisms behind the Bioactivity of Proteoglycan Replacement Therapy with Nourkrin® with Marilex® in Pattern Hair Loss and Telogen Effluvium

Follicular proteoglycans are key players with structural, functional, and regulatory roles in the growth and cycling behaviour of the hair follicles. The expression pattern of specific proteoglycans is strongly correlated with follicular phase transitions, which further affirms their functional involvement. Research shows that bioactive proteoglycans, e.g., versican and decorin, can actively trigger follicular phase shift by their anagen-inducing, anagen-maintaining, and immunoregulatory properties. This emerging insight has led to the recognition of “dysregulated proteoglycan metabolism” as a plausible causal or mediating pathology in hair growth disorders in both men and women. In support of this, declined expression of proteoglycans has been reported in cases of anagen shortening and follicular miniaturisation. To facilitate scientific communication, we propose designating this pathology “follicular hypoglycania (FHG),” which results from an impaired ability of follicular cells to replenish and maintain a minimum relative concentration of key proteoglycans during anagen. Lasting FHG may advance to structural decay, called proteoglycan follicular atrophy (PFA). This process is suggested to be an integral pathogenetic factor in pattern hair loss (PHL) and telogen effluvium (TE). To address FHG and PFA, a proteoglycan replacement therapy (PRT) program using oral administration of a marine-derived extract (Nourkrin® with Marilex®, produced by Pharma Medico Aps, Aarhus, Denmark) containing specific proteoglycans has been developed. In clinical studies, this treatment significantly reduced hair fall, promoted hair growth, and improved quality of life in patients with male- and female-pattern hair loss. Accordingly, PRT (using Nourkrin® with Marilex®) can be recommended as an add-on treatment or monotherapy in patients with PHL and TE.

Near infrared readouts offer sensitive and rapid assessments of intestinal permeability and disease severity in inflammatory bowel disease models

Intestinal permeability and neutrophil activity are closely linked to inflammatory bowel disease (IBD) pathophysiology. Here we discuss two techniques for assessing permeability and neutrophil activity in mouse IBD models using near infrared (NIR) detection. To address the limitation of visible light readouts-namely high background-IRDye 800CW was used to enable rapid, non-terminal measurements of intestinal permeability. The increased sensitivity of NIR readouts for colon permeability is shown using dextran sulfate sodium (DSS) and anti-CD40 murine colitis models in response to interleukin-22 immunoglobulin Fc (IL22Fc) fusion protein and anti-p40 monoclonal antibody treatments, respectively. In addition to enhanced permeability, elevated levels of neutrophil elastase (NE) have been reported in inflamed colonic mucosal tissue. Activatable NIR fluorescent probes have been extensively used for disease activity evaluation in oncologic animal models, and we demonstrate their translatability using a NE-activatable reagent to evaluate inflammation in DSS mice. Confocal laser endomicroscopy (CLE) and tissue imaging allow visualization of spatial NE activity throughout diseased colon as well as changes in disease severity from IL22Fc treatment. Our findings with the 800CW dye and the NE probe highlight the ease of their implementation in preclinical IBD research.

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.

A hyaluronic acid- and chondroitin sulfate-based medical device improves gastritis pain, discomfort, and endoscopic features

Gastritis is an inflammation of the gastric mucosa. In this study, we investigated the efficacy of a medical device, Esoxx®, based on hyaluronic acid and chondroitin sulfate on gastritis-related upper abdominal pain/discomfort and endoscopic features. Fifty patients, affected by gastritis, were randomised to receive the medical device or placebo. The primary endpoint was the medical device efficacy on upper abdominal pain/discomfort associated with gastritis and measured by Visual Analogue Scale (VAS). The secondary endpoints were the efficacy of the medical device on gastritis-related mucosal erosions, blood oozing, and hyperemia (redness)/edema, as assessed by endoscopy, and the patients’ rating of their compliance with the treatments. A significant reduction in VAS pain was observed in the treatment group after a 5-week treatment, if compared with placebo (p < 0.001). In summary, administration of a medical device, based on hyaluronic acid and chondroitin sulfate, improves gastritis-related upper abdominal pain/discomfort and decreases mucosal erosions, blood oozing, and hyperemia (redness)/edema at 5-week follow-up in patients affected by gastritis.

Oral Bioavailability and Pharmacokinetics of Nonanimal Chondroitin Sulfate and Its Constituents in Healthy Male Volunteers

The pharmacokinetic profile of a new 800-mg tablet of nonanimal chondroitin sulfate (CS) (Mythocondro®, 800-mg tablets, Gnosis S.p.A., Italy) was investigated vs an animal CS in healthy volunteers for a total period of 48 hours. After a single 2400-mg dose of the test and the reference formulation, total CS, the compositional disaccharides (ΔDi6S, ΔDi4S and ΔDi0S), and the overall charge density were quantified in plasma. The safety and tolerability profile after a single dose of this new nonanimal CS tablets was excellent. After baseline-corrected concentrations, an overall greater plasma concentration was observed after 24 hours of ∼44% and after 48 hours of ∼45% from administration of nonanimal when compared to animal-derived CS. Moreover, nonanimal CS increases the specific sulfation in the 6-position of N-acetyl-galactosamine in human plasma CS and, as a consequence, the overall charge density, reaching double values (0.91), after 48 hours compared to bovine CS and to endogenous CS. In conclusion, nonanimal CS, possessing a lower molecular weight than an animal-derived sample, produces a greater CS concentration for a more prolonged period of time in plasma and an increase in charge density and specific 6-sulfation of endogenous plasma CS.

Oral Administration and Detection of a Near-Infrared Molecular Imaging Agent in an Orthotopic Mouse Model for Breast Cancer Screening

Molecular imaging is advantageous for screening diseases such as breast cancer by providing precise spatial information on disease-associated biomarkers, something neither blood tests nor anatomical imaging can achieve. However, the high cost and risks of ionizing radiation for several molecular imaging modalities have prevented a feasible and scalable approach for screening. Clinical studies have demonstrated the ability to detect breast tumors using nonspecific probes such as indocyanine green, but the lack of molecular information and required intravenous contrast agent does not provide a significant benefit over current noninvasive imaging techniques. Here we demonstrate that negatively charged sulfate groups, commonly used to improve solubility of near-infrared fluorophores, enable sufficient oral absorption and targeting of fluorescent molecular imaging agents for completely noninvasive detection of diseased tissue such as breast cancer. These functional groups improve the pharmacokinetic properties of affinity ligands to achieve targeting efficiencies compatible with clinical imaging devices using safe, nonionizing radiation (near-infrared light). Together, this enables development of a “disease screening pill” capable of oral absorption and systemic availability, target binding, background clearance, and imaging at clinically relevant depths for breast cancer screening. This approach should be adaptable to other molecular targets and diseases for use as a new class of screening agents.

A Turn-on Fluorescence Sensor for Heparin Detection Based on a Release of Taiwan Cobra Cardiotoxin from a DNA Aptamer or Adenosine-Based Molecular Beacon

This study presents two sensitive fluorescent assays for sensing heparin on the basis of the electrostatic interaction between heparin and Naja naja atra cardiotoxin 3 (CTX3). Owing to CTX3-induced folded structure of an adenosine-based molecular beacon (MB) or a DNA aptamer against CTX3, a reduction in the fluorescent signal of the aptamer or MB 5'-end labeled with carboxyfluorescein (FAM) and 3'-end labeled with 4-([4-(dimethylamino)phenyl]azo)-benzoic acid (DABCYL) was observed upon the addition of CTX3. The presence of heparin and formation of the CTX3-heparin complex caused CTX3 detachment from the MB or aptamer, and restoration of FAM fluorescence of the 5'-FAM-and-3'-DABCYL-labeled MB and aptamer was subsequently noted. Moreover, the detection of heparin with these CTX3-aptamer and CTX3-MB sensors showed high sensitivity and selectivity toward heparin over chondroitin sulfate and hyaluronic acid regardless of the presence of plasma. The limit of detection for heparin in plasma was determined to be 16 ng/mL and 15 ng/mL, respectively, at a signal-to-noise ratio of 3. This study validates the practical utility of the CTX3-aptamer and CTX3-MB systems for determining the concentration of heparin in a biological matrix.

Access to Highly Purified Chondroitin Sulfate for Appropriate Treatment of Osteoarthritis: A Review

Current pharmacological therapies for osteoarthritis are symptom-focused and aimed at controlling pain. However, currently approved symptom-modifying agents do not restore the structure and function of damaged joints. Symptomatic slow-acting drugs in osteoarthritis (SySADOAs), including the sulfated glycosaminoglycan, chondroitin sulfate, have shown promising beneficial effects on the pain and other symptoms of osteoarthritis, and some may also have a positive effect on cartilage, slowing the progression of joint deterioration in osteoarthritis. A highly-purified, standardized, pharmaceutical-grade preparation of chondroitin sulfate has shown activity in osteoarthritis and has become one of the most prescribed SySADOAs. However, in many countries, formulations of chondroitin sulfate of various sources and purity are available as food supplements or nutraceuticals. As the effects of chondroitin sulfate could vary according to the characteristics of the chondroitin sulfate employed, including source, purity, or structural organization, clinical data from well-designed studies of pharmaceutical-grade chondroitin sulfate should not be extrapolated to support clinical efficacy claims of food supplements; nor should results from trials of chondroitin sulfate-containing food supplements be used to draw conclusions about the efficacy of pharmaceutical-grade chondroitin sulfate. This article reviews the evidence for the role of highly-purified pharmaceutical-grade chondroitin sulfate in the treatment of osteoarthritis and examines the efficacy and safety concerns of other formulations of chondroitin sulfate. Highly-purified pharmaceutical-grade chondroitin sulfate has mild-to-moderate efficacy in the treatment of symptomatic osteoarthritis, with clinically meaningful efficacy.

Improved anticoagulant effect of fucosylated chondroitin sulfate orally administered as gastroresistant tablets

Fucosylated chondroitin sulfate (FucCS) is a potent anticoagulant polysaccharide extracted from sea cucumber. Its anticoagulant activity is attributed to the presence of unique branches of sulfated fucose. Although this glycosaminoglycan exerts an antithrombotic effect following oral administration, high doses are necessary to achieve the maximum effect. The diminished activity of FucCS following oral administration is likely due to its degradation in the gastrointestinal tract and its limited ability to cross the intestinal cell membranes. The latter aspect is particularly difficult to overcome. However, gastroresistant tablet formulation may help limit the degradation of FucCS in the gastrointestinal tract. In the present work, we found that the oral administration of FucCS as gastroresistant tablets produces a more potent and prolonged anticoagulant effect compared with its administration as an aqueous solution, with no significant changes in the bleeding tendency or arterial blood pressure. Experiments using animal models of arterial thrombosis initiated by endothelial injury demonstrated that FucCS delivered as gastro-protective tablets produced a potent antithrombotic effect, whereas its aqueous solution was ineffective. However, there was no significant difference between the effects of FucCS delivered as gastroresistant tablets or as aqueous solution in a venous thrombosis model, likely due to the high dose of thromboplastin used. New oral anticoagulants tested in these experimental models for comparison showed significantly increased bleeding tendencies. Our study provides a framework for developing effective oral anticoagulants based on sulfated polysaccharides from marine organisms. The present results suggest that FucCS is a promising oral anticoagulant.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Absorption of Orally Administered Hyaluronan

Hyaluronan (HA) has been utilized as a supplement. However, the absorption of orally administrated HA remains controversial. The degradation and absorption of HA in the intestine were investigated in this study. HA excretion into the feces, degradation in the intestinal tract, absorption through the large intestine, and translocation to the blood and skin were examined. HA administered orally was not detected in rat feces. HA was degraded by cecal content, but not by artificial gastric juice and intestinal juice. Oligosaccharide HA passed through excised large intestine sacs. Furthermore, disaccharides, tetrasaccharides, and polysaccharides HA were distributed to the skin of rats following oral administration of high molecular weight HA (300 kDa). The results of the study suggest that orally administered HA is degraded to oligosaccharides by intestinal bacteria, and oligosaccharide HA is absorbed in the large intestine and is subsequently distributed throughout the tissues, including the skin.

Glucosamine and chondroitin for the treatment of osteoarthritis

The prevalence of primary or idiopathic osteoarthritis (OA) of knee and hip joints has substantially increased in general population during the last decades. Analgesics and non-steroidal anti-inflammatory drugs are currently extensively used as non-surgical treatment options. However, they act as symptomatic treatments, not offering a cure of OA and they are accused for an increased risk of adverse events. Glucosamine (GL) and chondroitin (CH) are nutritional supplements that have recently gained widespread use as treatment options for OA. They potentially or theoretically act as chondroprotectors or/and as “disease-modifying OA drugs” offering not only symptomatic relief but also alteration of the natural history of OA. However, although many studies have showed a significant treatment effect, accompanied with remarkable safety, there is still controversy regarding their relative effectiveness compared with placebo or other treatments. The scope of this review is to present and critically evaluate the current evidence-based information regarding the administration of GL and CH for the treatment of knee or hip OA. Our focus is to investigate the clinical efficacy and safety after the use of these supplements. An effect of GL and CH on both clinical and radiological findings has been shown. However, only a few high-quality level I trials exist in the literature, especially on the assessment of radiological progression of OA. The effect sizes are generally small and probably not clinically relevant. Even the validity of these results is limited by the high risk of bias introduced in the studies. Both GL and CH seem to be safe with no serious adverse events reported. There is currently no convincing information for the efficacy of GL and CH on OA.

Design of chondroitin sulfate-based polyelectrolyte nanoplexes: Formation of nanocarriers with chitosan and a case study of salmon calcitonin

The aim of this work was to examine the formation and properties of chondroitin sulfate (CHON)-based nanoparticles (NPs), namely CHON/chitosan (CHIT), CHON/CHIT/calcitonin (sCT) and CHON/sCT. Both, positively and negatively charged CHON/CHIT NPs have been successfully obtained with properties that were dependent on the polymer mixing ratio, polymer concentration and molecular weight of CHIT. sCT was successfully loaded into CHON/CHIT NPs with efficiency close to 100% and notably high loading (up to 33%). A new type of NPs composed of CHON and sCT (a binary system) has been successfully developed. CHON/sCT NPs offer the advantage of a very high drug loading up to 73%. The particle size of CHON-based NPs increased in PBS, acetate buffer and in HCl solution compared to that in water, but most of them remained in the nano-range even after 24h. The media and composition of the nanocarriers were found to affect the release of sCT.

Preclinical evaluation of (99m)Tc labeled chondroitin sulfate for monitoring of cartilage degeneration in osteoarthritis

PURPOSE

In previous in-vitro and ex-vivo studies we proved the specific uptake of (99m)Tc radiolabeled chondroitin sulfate (CS) in human articular cartilage. As a logical next step for the clinical use for imaging osteoarthritis we investigated in-vivo uptake of (99m)TcCS in dogs.

PROCEDURES

The radiolabeling of CS Condrosulf (IBSA, Lugano, Switzerland) was performed using 25mg of CS and 20-40MBq/kg body weight of (99m)Tc by means of the tin method. In-vivo uptake of (99m)TcCS was evaluated in dogs (n=12, castrated males, 4-9years, with 15-51kg body weight). 6 healthy dogs served as controls and 6 with clinical and radiological signs of osteoarthritis in the carpal, elbow, and tarsal joint were examined. The tracer was i.v. injected into the external cephalic vein. The uptake was monitored after 2, 4, 6 and 24h in healthy and osteoarthritic dogs using a planar gamma camera by regional planar or whole body ventral and dorsal acquisition. For whole body scintigraphy animals were under general anesthesia, for planar under sedation only.

RESULTS

In healthy control dogs we did not detect any specific uptake of (99m)TcCS in the cartilage. In contrast, in the diseased dogs suffering from osteoarthritis a significant, specific, persistent uptake between 4 and 6h in tarsal, carpal and cubital joints was documented. Median target (joint) to background (mid antebrachium) ratio (T/B) in the OA joints after 4, 6, and 24h was significantly higher than in healthy controls. Target to background ratio using soft tissue as a background (T/S) a similar significantly higher than in healthy controls. In all osteoarthritic joints we found a significant positive correlation (r=0.8, n=20) between grade of disease (I-III) and T/B. When matching radiographic (X ray) changes in osteoarthritic joints (grade II and III) we found also a maximal uptake of (99m)TcCS at the specific anatomical site of highest cartilage degeneration. None of the dogs experienced any side effects.

CONCLUSION

These results suggest that (99m)TcCS might become a promising diagnostic tool for imaging osteoarthritis. More extensive and detailed examinations are required, however, before extending this methodology for application in humans.

Metabolic fate of milk glycosaminoglycans in breastfed and formula fed newborns

In this study, the content, structure and residual percentages of glycosaminoglycans (GAGs) in the feces of seven breastfed newborns after ingesting a known amount of milk were studied. A comparison was made with five newborns fed with formula milk. Characterization of GAGs from milk and feces samples was performed according to previous methodology. Compared to the ingested GAGs present in milk, residual feces GAGs of breastfed newborns were <0.4 %, contrary to formula milk fed children, where the residues were ~4 %. As a consequence, >99 % of human milk GAGs are utilized as opposed to ~96 % of formula milk. Hyaluronic acid utilization was found to be fairly similar contrary to chondroitin sulfate/dermatan sulfate and heparan sulfate, which were found to be ~10-18 times lower in formula milk fed children. Our new results further demonstrate that the elevated content of human milk GAGs passes undigested through the entire digestive system of newborns, possibly protecting the infant from infections. In the distal gastrointestinal tract, these complex macromolecules are catabolized by a cohort of bacterial enzymes and constituent monosaccharides/oligosaccharides utilized for further metabolic purposes potentially useful for bacteria metabolism or internalized by intestinal cells. Thanks to their elevated structural heterogeneity, milk GAGs are used differently depending on their distinct primary structure. Finally, a different utilization and availability was observed for human milk GAGs compared to formula milk due to their various composition and structural heterogeneity.

Degradation of chondroitin sulfate by the gut microbiota of Chinese individuals

Oral preparations of chondroitin sulfate (CS) have long been used as anti-osteoarthritis (anti-OA) drugs. However, little is known about the degradation of CS by human gut microbiota. In the present study, degradation profiles of CSA (the main constituent of CS drugs) by the human gut microbiota from six healthy subjects were investigated. Each individual's microbiota had differing degradation activities, but ΔUA-GalNAc4S was the end product in all cases. To elucidate the mechanisms underlying this phenomenon, different CSA-degrading bacteria were isolated from each individual's microbiota and tested for CSA degradation. In addition to Bacteroides thetaiotaomicron J1, Bacteroides thetaiotaomicron 82 and Bacteroides ovatus E3, a new CSA-degrading bacterium, Clostridium hathewayi R4, was isolated and characterized. Interestingly, at least two different CSA-degrading species were identified from each individual's gut microbiota. Predictably, these functional bacteria also had differing degradation rates, but still generated the same end product, ΔUA-GalNAc4S. In addition, the human fecal isolates produced different degradation profiles for CSC, CSD, and CSE, suggesting that CS could be readily metabolized to varying extents by diverse microbial consortiums, which may help to explain the poor bioavailability and unequal efficacy of CS among individuals in OA treatment.

Discrepancies in composition and biological effects of different formulations of chondroitin sulfate

Osteoarthritis is a common, progressive joint disease, and treatments generally aim for symptomatic improvement. However, SYmptomatic Slow-Acting Drugs in Osteoarthritis (SYSADOAs) not only reduce joint pain, but slow structural disease progression. One such agent is chondroitin sulfate—a complex, heterogeneous polysaccharide. It is extracted from various animal cartilages, thus has a wide range of molecular weights and different amounts and patterns of sulfation. Chondroitin sulfate has an excellent safety profile, and although various meta-analyses have concluded that it has a beneficial effect on symptoms and structure, others have concluded little or no benefit. This may be due, at least partly, to variations in the quality of the chondroitin sulfate used for a particular study. Chondroitin sulfate is available as pharmaceutical- and nutraceutical-grade products, and the latter have great variations in preparation, composition, purity and effects. Moreover, some products contain a negligible amount of chondroitin sulfate and among samples with reasonable amounts, in vitro testing showed widely varying effects. Of importance, although some showed anti-inflammatory effects, others demonstrated weak effects, and some instances were even pro-inflammatory. This could be related to contaminants, which depend on the origin, production and purification process. It is therefore vitally important that only pharmaceutical-grade chondroitin sulfate be used for treating osteoarthritis patients.

Nutraceuticals in the management of osteoarthritis : a critical review

Osteoarthritis (OA) is a chronic, highly prevalent and disabling disease that is expected to increase in prevalence secondary to longer life expectancy and a disproportionately aging population. Treatment of OA is only marginally effective and has been focused primarily on symptom control using weight loss, physical therapy, nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, intra-articular steroids or viscosupplementation, topical NSAIDs and analgesics, diacerein (an oral interleukin-1β inhibitor) and finally joint replacement surgery. The use of nutraceuticals in the treatment of OA is common, and scientific studies examining the effects of nutraceuticals on the pathogenesis and treatment of OA are increasing. This review examines the efficacy and safety of select nutraceuticals for the treatment of OA. The reviewed nutraceuticals include glucosamine, chondroitin, collagen hydrolysates (CHs) and avocado-soybean unsaponifiables (ASUs). There have been several clinical trials examining the efficacy of these products and the results demonstrate significant heterogeneity. Significant improvements in pain, function and structural outcomes have been shown for some of the treatment arms or subgroups of patients, but the effects are not consistent across the studies. Glucosamine, chondroitin and the two in combination have been the most extensively studied. Significant improvement in pain and functional indices and a decrease in the loss of joint space width were demonstrated in some but not all studies. CHs showed significant improvement in pain and functional indices for several subgroups of patients, but these findings were not pervasive amongst the treatment arms. ASU has demonstrated positive results with respect to decreased NSAID use in several studies and functional and pain end points in most of the reviewed studies; however, in the two studies examining structural end points, the results were mixed. The safety of these nutraceuticals has been demonstrated across all of the reviewed trials, and there were no significant issues with tolerance. Given the good safety profile of nutraceuticals, the marginal efficacy of conventional treatments, the high prevalence and rate of disability from OA and the possible benefit of nutraceuticals to patients with OA, use of nutraceuticals in select patients is appropriate. An overall recommendation to use nutraceuticals in the treatment of all patients with OA is not strongly supported by the available data. Future studies should focus on standardization of symptomatic and structural outcome measures, be of longer duration and pay careful attention to the content of the investigational product.