Preparation and in vitro anticoagulant activities of alginate sulfate and its quaterized derivatives

Huang, Ronghua; Du, Yumin; Yang, Jianhong

doi:10.1016/s0144-8617(02)00258-8

Cited by 107 publications

(57 citation statements)

References 17 publications

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“…42 Lately, Ronghua et al 30 showed that alginate sulfate has anticoagulant properties comparable to heparin. However, the use of alginate sulfate for tissue engineering applications is limited to a few studies.…”

Section: Discussionmentioning

confidence: 99%

Chondrocyte Culture in Three Dimensional Alginate Sulfate Hydrogels Promotes Proliferation While Maintaining Expression of Chondrogenic Markers

Mhanna

Kashyap

Palazzolo

et al. 2014

Tissue Engineering Part A

102

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The loss of expression of chondrogenic markers during monolayer expansion remains a stumbling block for cell-based treatment of cartilage lesions. Here, we introduce sulfated alginate hydrogels as a cartilage biomimetic biomaterial that induces cell proliferation while maintaining the chondrogenic phenotype of encapsulated chondrocytes. Hydroxyl groups of alginate were converted to sulfates by incubation with sulfur trioxidepyridine complex (SO 3 /pyridine), yielding a sulfated material cross-linkable with calcium chloride. Passage 3 bovine chondrocytes were encapsulated in alginate and alginate sulfate hydrogels for up to 35 days. Cell proliferation was five-fold higher in alginate sulfate compared with alginate ( p = 0.038). Blocking beta1 integrins in chondrocytes within alginate sulfate hydrogels significantly inhibited proliferation ( p = 0.002). Sulfated alginate increased the RhoA activity of chondrocytes compared with unmodified alginate, an increase that was blocked by b1 blocking antibodies ( p = 0.017). Expression and synthesis of type II collagen, type I collagen, and proteoglycan was not significantly affected by the encapsulation material evidenced by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. Alginate sulfate constructs showed an opaque appearance in culture, whereas the unmodified alginate samples remained translucent. In conclusion, alginate sulfate provides a three dimensional microenvironment that promotes both chondrocyte proliferation and maintenance of the chondrogenic phenotype and represents an important advance for chondrocyte-based cartilage repair therapies providing a material in which cell expansion can be done in situ.

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Section: Discussionmentioning

confidence: 99%

Chondrocyte Culture in Three Dimensional Alginate Sulfate Hydrogels Promotes Proliferation While Maintaining Expression of Chondrogenic Markers

Mhanna

Kashyap

Palazzolo

et al. 2014

Tissue Engineering Part A

102

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“…In addition, alginates have many biomedical and biotechnological applications. For example, alginates have anticoagulant activity (Ronghua et al 2003). Furthermore, it has been shown that low molecular weight alginates could be useful in the prevention of obesity, hypercholesterolemia, and diabetes (Tze and Tai 1982;Soon-Shiong et al 1994;Kimura et al 1996).…”

Section: Introductionmentioning

confidence: 99%

Extracted and depolymerized alginates from brown algae Sargassum vulgare of Lebanese origin: chemical, rheological, and antioxidant properties

et al. 2015

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International audiencePurified sodium alginate (PS alginate) was isolated from the brown seaweed Sargassum vulgare collected from the Lebanese Mediterranean coast and then depolymerized into homopolymeric polyguluronate (PolyG) and polymannuronate (PolyM) blocks by controlled acid hydrolysis. These fractions of PS alginate issued from S. vulgare were characterized in terms of composition and structure by SEC, elemental analysis, FTIR and 1H and 13C NMR spectroscopy. An alginate with a low content of protein (\textless0.62 %) and a molecular weight of 110 200 g mol-1 was identified as sole polysaccharide. Depolymerized PS alginate fractions, PolyG (32.6 %) and PolyM (22.3 %), were found to have close molecular weights, of 7500 and 6900 g mol-1, respectively. From NMR analysis, values of F G, F M, M/G ratio, F GG, F MM, and F GM (or F MG) blocks were determined and compared with those of alginates from S. vulgare of Brazilian origin and other Sargassum species. Our PS alginate appeared different from the Brazilian S. vulgare alginate, with a lower M/G ratio (0.785 instead of 1.27), a predominance of the G blocks (F G and F GG \textgreater 0.5) instead of the M blocks, and it showed more similarity to the composition of some alginates extracted from other species of Sargassum. High G or M contents (≥80 %) were measured from PolyG and PolyM blocks, respectively. The viscosity of the PS alginate and its fractions PolyG and PolyM was determined. PS alginate from S. vulgare of Lebanese origin showed a Newtonian flow behavior for concentration lower than 0.5 % in 0.1 M NaCl solution, while a shear-thinning pseudoplastic behavior is observed for concentration range between 0.75 and 10 %. Also, storage (G′) and loss (G″) moduli were studied for two concentrations of PS alginate solutions (5 and 10 %). Antioxidant properties of the non-depolymerized and depolymerized alginates were evaluated by determining the scavenging ability of the stable radical DPPH (2,2-diphenyl-1 picrylhydrazyl). Clearly, the results demonstrated differences in radical scavenging efficacy between PolyG and PolyM fractions. The higher hydroxyl radical scavenging activity was observed for the PolyG fractions (~92 % at 2 mg mL-1) and this activity was comparable with those of standard antioxidants. These PolyG fractions could be valuable in foods or pharmaceutical products as alternatives to synthetic antioxidant

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“…Attempts for synthesising of heparin structure analogues have been conducted. Semi-synthetic heparinoids based on chitosan sulfate [5,6] or alginate sulfate [7] have been prepared.…”

Section: Introductionmentioning

confidence: 99%

Copolymers of 2-acryloylamido-2-methylpropanesulfonic acid and acrylic acid with anticoagulant activity

et al. 2003

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Copolymers of 2-acryloylamido-2-methylpropanesulfonic acid (AMPS) and acrylic acid (AA), as well as the corresponding homopolymers PAMPS and PAA, were studied in vitro on human pool plasma for their anticoagulant activity. The values of the haemostatic parameters -prothrombin time, activated partial thromboplastin time and thrombin time -depend on the composition and the concentration of the (co)polymers. Reptilase time remains unchanged on adding the (co)polymers. A broad concentration range from 16 µg/ml to 3 mg/ml was studied. The copolymers possess anticoagulant activity, which is higher at higher content of AMPS units. It was found that, at certain concentrations, the haemostatic parameters of PAMPS are close to that of heparin. PAA has the lowest anticoagulant activity.

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Preparation and in vitro anticoagulant activities of alginate sulfate and its quaterized derivatives

Cited by 107 publications

References 17 publications

Chondrocyte Culture in Three Dimensional Alginate Sulfate Hydrogels Promotes Proliferation While Maintaining Expression of Chondrogenic Markers

Chondrocyte Culture in Three Dimensional Alginate Sulfate Hydrogels Promotes Proliferation While Maintaining Expression of Chondrogenic Markers

Extracted and depolymerized alginates from brown algae Sargassum vulgare of Lebanese origin: chemical, rheological, and antioxidant properties

Copolymers of 2-acryloylamido-2-methylpropanesulfonic acid and acrylic acid with anticoagulant activity

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