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PubMed2006

Cutaneous granulomatous reaction to injectable hyaluronic acid gel.

Injectable hyaluronic acid (HA) derivatives are the most used reabsorbable dermal fillers for soft tissue augmentation today and their utilization is considered safe. We report a cutaneous granulomatous reaction that developed in a woman 5 weeks after the first treatment with a nonanimal HA derivative for the correction of facial wrinkling. We describe the clinicopathological findings and course of the cutaneous reaction. The adverse reaction showed clinical and histopathological characteristics comparable to the few previously reported cases. All cutaneous lesions spontaneously disappeared without scars within 3 months. We conclude that even nonanimal injectable HA derivatives can be associated with delayed granulomatous reactions. The patient should be informed of this potential long-term complication.

Adult↗
PubMed1986

Human fibrinogen specifically binds hyaluronic acid.

Fibrin and hyaluronic acid (HA) are macromolecules whose concentrations are elevated at the same time in the extracellular space of damaged tissues. We have investigated whether HA can bind to fibrinogen using solid phase and soluble assays. Purified human fibrinogen specifically bound to HA-Sepharose to a greater extent (greater than 5-fold) than did alpha 1-acid glycoprotein, DNaseI, ovalbumin, haptoglobin, or lysozyme. Fibrinogen did not bind to ethanolamine-Sepharose, a control chromatographic support. Treatment of HA-Sepharose containing bound 125I-fibrinogen with ovine testicular hyaluronidase released 44% of the 125I radioactivity, indicating that fibrinogen was specifically bound to HA. Moreover, 125I-fibrinogen bound to HA-Sepharose could be displaced by free HA but not by either of the monosaccharide components of this polymer, glucuronic acid, or N-acetylglucosamine. Chondroitin sulfate and polygalacturonic acid competed only weakly for bound 125I-fibrinogen. Bound 125I-fibrinogen was also not released by high concentrations of NaCl (up to 4 M), indicating that the interaction is not simply ionic. The apparent affinity of fibrinogen for HA covaried with the molecular weight of the HA. Small HA oligosaccharides (Mr = 3900) were only 50% as effective as larger HA (Mr = 8 X 10(5)) in eluting bound 125I-fibrinogen from HA-Sepharose. The optimal oligosaccharide size for displacement of bound 125I-fibrinogen was greater than or equal to 200 monosaccharides. Additionally, the amount of 125I-fibrinogen bound to HA-Sepharose was directly related to the size of the HA-amine linked to the affinity support. The affinity constant for fibrinogen binding to 125I-HA (approximately 150 monosaccharides) is estimated to be at least 2 X 10(7) M-1. These results demonstrate for the first time a specific, reversible binding between HA and fibrinogen.

Electrophoresis, Polyacrylamide Gel↗
PubMed1976

Inhibition of proteoglycan biosynthesis by hyaluronic acid in chondrocytes in cell culture.

The depression of proteoglycan synthesis in ten-day-old high density chondrocyte cultures was shown to be dependent on both the concentration and time of exposure of the cells to hyaluronic acid. Hyaluronic acid had no effect on the overall protein synthesis by the cultured cells. Using benzyl-beta-D-xyloside an exogenous acceptor, it was shown that glycosaminoglycan biosynthesis by the chondrocytes was not affected by hyaluronic acid. It was concluded that hyaluronic acid was effecting glycosaminoglycan chain initiation, hence proteoglycan biosynthesis, either by specifically depressing the synthesis of the core protein or by repressing the activity of the xylosyltransferase.

Acetates↗
PubMed2001

Glycolic acid treatment increases type I collagen mRNA and hyaluronic acid content of human skin.

BACKGROUND: Chronic solar irradiation results in both morphologic and functional changes in affected skin. alpha-hydroxy acids, such as glycolic acid, have been shown to improve photodamaged skin. OBJECTIVE: To investigate alterations in collagen gene induction and epidermal and dermal hyaluronic acid production as a result of administered glycolic acid. METHODS: In this study we compared collagen gene expression from skin biopsy specimens, and epidermal and dermal hyaluronic acid immunohistochemical staining between glycolic acid-treated and vehicle-treated skin. Forearm skin was treated with 20% glycolic acid lotion or a lotion vehicle control twice a day for 3 months. RESULTS: Epidermal and dermal hyaluronic acid and collagen gene expression were all increased in glycolic acid-treated skin as compared to vehicle-treated controls. CONCLUSION: Our data suggest that epidermal and dermal remodeling of the extracellular matrix results from glycolic acid treatment. Longer treatment intervals may result in collagen deposition as suggested by the measured increase in mRNA.

Aged↗
PubMedDate not supplied

Biotinylated hyaluronic acid: a new tool for probing hyaluronate-receptor interactions.

Hyaluronic acid (HA) is a linear polysaccharide composed of repeating disaccharide units of D-glucuronic acid (GlcUA) and N-acetyl-D-glucosamine (GlcNAc). Hyaluronate plays an important role in many biological processes as mediated by its interactions with a number of HA-binding proteins (the "hyaladherins") and with the cell surface HA-receptor, CD44. Studies of hyaluronate-hyaladherin interactions would be greatly facilitated by the availability of molecular probes derived from HA. We recently reported a convenient chemical modification of hyaluronate that introduces multiple pendant amine functionalities onto the HA carboxylate residues. We now report the preparation of biotinylated hyaluronic acid (molecular weight = 1.2 x 10(6) Da) as a probe for histochemical and immunochemical characterization of HA-binding proteins. Approximately one-third of the available HA glucuronate residues could be readily biotinylated in high molecular weight HA.

Biotin↗
PubMed1987

Hyaluronic acid degradation by ascorbic acid and influence of iron.

The effects of ascorbic acid, iron and ADP on hyaluronic acid, a compound present in inflamed joints, were investigated in an in vitro system. Ascorbic acid induces degradation of hyaluronic acid which increased in the presence of FeCl3 and which is additionally stimulated by ADP chelated ferric ions. The hyaluronic acid degrading reactions induced by the Fe-III/ADP/ascorbic acid system were inhibited by catalase and formate to various extents whereas the presence of superoxide dismutase did not exert any inhibitory effect. Desferrioxamine, a specific iron chelator, completely inhibited hyaluronic acid depolymerisation by ascorbic acid as well as in combination with FeCl3 or FeCl3/ADP, respectively. We suggest that the ultimate hyaluronic acid degrading species is OH, generated via the Fe-III/ADP catalysed Haber Weiss reaction. There is also an indication for the involvement of perferryl or/and ferryl species in the degradation process.

Adenosine Diphosphate↗
PubMed2000

Complementary characterization of a hyaluronic acid splitting enzyme from Streptococcus agalactiae.

A hyaluronic acid splitting enzyme of Streptococcus agalactiae was characterized by splitting mechanism, Michaelis-constant and inhibition type for sulfated hyaluronic acid: The enzyme splits hyaluronic acid as a hyaluronate lyase [EC 4.2.2.1]. The Km = 8 x 10(-4) mg ml-1 was determined with the influence of substrate inhibition constant Kiu = 2 x 10(-6) mg ml-1. Sulfated hyaluronic acid inhibits the enzyme in a partially non-competitive way. The inhibition constant is Ki = 5.47 x 10(-4) mg ml-1. The GBS-hyaluronate lyase cleaves hyaluronic acid as an endoglycosidase. The work is related with the intention to establish a hyaluronate lyase of microbial origin as a therapeutical enzyme replacing bovine hyaluronidase.

Animals↗
PubMed1983

Hyaluronic acid double helix.

The hyaluronic acid double helix, contrary to an earlier visualization, probably incorporates extensively hydrogen-bonded chains and is pinned together by carboxyl-carboxylate hydrogen bonds and water bridges. Transient interactions between stiffened chain segments provided by the formation of double-helical loops could give rise to the characteristic viscoelastic properties of hyaluronic acid solutions.

Carbohydrate Conformation↗
PubMedDate not supplied

Modulation of airspace enlargement in elastase-induced emphysema by intratracheal instillment of hyaluronidase and hyaluronic acid.

The study examined how lung hyaluronic acid content influences airspace enlargement in elastase-induced emphysema. To determine the effect of a decrease in hyaluronic acid, hamsters received a single intratracheal instillment of hyaluronidase 24 h prior to administration of pancreatic elastase by the same route. One week later, these animals showed significantly greater airspace enlargement than controls sequentially instilled with saline and elastase (128 vs. 100 microns; p < .05). Conversely, intratracheal administration of hyaluronic acid immediately after elastase instillment resulted in a marked decrease in airspace enlargement at 1 week compared to controls receiving elastase followed by saline (82 vs. 122 microns; p = .005). Since hyaluronic acid has no elastase inhibitory capacity, its effect may involve extracellular matrix interactions not directly related to elastic fiber breakdown. This concept is supported by the finding that animals treated with hyaluronidase and elastase showed no greater loss of lung elastin than that observed in the saline/elastase control group, despite demonstrating a marked increase in airspace enlargement. Further work is needed to determine how hyaluronic acid influences airspace enlargement and to evaluate the potential use of this substance as a treatment for emphysema.

Animals↗
PubMedDate not supplied

Efficient synthesis of an aldehyde functionalized hyaluronic acid and its application in the preparation of hyaluronan-lipid conjugates.

An efficient method to synthesize hyaluronan oligosaccharide lipid conjugates is described. This strategy is based on the introduction of a double bond in the glucuronic acid of the hyaluronic acid (HA), by the biodegradation of HA with hyaluronate lyase, followed by the generation of a free aldehyde group at the nonreducing end of hyaluronic acid via ozonolysis and the subsequent reduction of the generated ozonide. The resulting aldehyde-functionalized HA is then coupled to dipalmitoyl phosphatidylethanolamine (DPPE) using reductive amination chemistry. This methodology can be extended to link molecules such as biotin, polymers, or proteins to HA for numerous applications in drug delivery and in the creation of biocompatible materials for tissue repair and engineering.

Aldehydes↗
PubMed1985

Effects of adjuvants to local anaesthetics on their duration. III. Experimental studies of hyaluronic acid.

The effects of addition of hyaluronic acid (sodium hyaluronate, Healon) to different local anaesthetics of the amide type on the duration of sensory or motor blocks following various regional anaesthetic procedures were studied in animal experiments. In the rat infra-orbital nerve block model, the addition of 0.1-0.5% hyaluronic acid (HA) to 2% prilocaine increased the duration of sensory block of varying degrees in a dose-dependent way by up to 500% of values obtained with plain prilocaine. The duration of degree 5 blocks produced by 0.5% etidocaine and 0.5% bupivacaine was also significantly prolonged when 0.4% HA was included to 206% and 282% of control, respectively, while blocks induced by 2% lidocaine were prolonged to 123% of control. The duration of motor block following spinal anaesthesia in the mouse was prolonged in a dose-dependent way when HA was added to prilocaine, bupivacaine and etidocaine. For solutions containing 0.4% HA, prolongations to 254%, 166% and 134% of control, respectively, were obtained. A concomitant increase of latency to onset of block and failure rate occurred with increasing concentrations of HA. The duration of corneal anaesthesia in the rabbit increased by 57% and 44% when 0.3% HA was added to prilocaine and bupivacaine, respectively. The duration of infiltration anaesthesia was not affected by the addition of HA to the local anaesthetic solutions. Addition of HA had no effect on the onset, depth and duration of prilocaine-induced block of the nervous transmission in vitro. The duration of infra-orbital nerve block and spinal anaesthesia shows a significant relation to the relative viscosity of the local anaesthetic solution.

Anesthetics, Local↗
PubMed1996

Blood-interaction performance of differently sulphated hyaluronic acids.

Seven differently sulphated hyaluronic acid derivatives, having a general formula HyalSx where x can be 1, 2, 2.5, 3, 3.5, 3.8, 4, were synthetized. Coagulation tests i.e. whole blood clotting time and thrombin time were performed on these compounds and significant prolongations were observed from HyalS2.5 up to HyalS4. All that means the heparin like activity increases by increasing the sulphation degree of hyaluronic acid. The interaction of each of them with thrombin and FXa was studied in order to understand the mechanism of coagulation inactivation and the role of the sulphate position in the disaccharide unit to favour the protease inhibiting reaction. The bioactivity of HyalSx in terms of FXa and thrombin inactivation increases increasing with sulphation degree but the FXa inactivation seems to be mediated by ATIII, while the aspecific electrostatic interaction seems to play an important role in the inactivation of thrombin. Also the interaction with human serum albumin was studied by ATR/FT-IR technique and no changes of protein conformation was observed, as occurs in the case of heparin.

Adsorption↗
PubMed1994

Biodegradation of hyaluronic acid derivatives by hyaluronidase.

Hyaluronic acid (salt) (HA) has been chemically modified as a biomaterial for medical applications such as controlled drug release matrices, nerve guides and wound dressings. A series of HA derivatives, which include different ester types and different degrees of esterification, have been used to investigate the stability of these materials in testicular hyaluronidase. Gel permeation chromatography and capillary viscometer have been employed to determine the size of the molecules, the former used for the water insoluble derivatives that dissolve in dimethyl sulphoxide, the latter for the water soluble samples. The preliminary experimental results indicated that the molecular weight of fully esterified hyaluronic acid (both ethyl and benzyl esters) did not decrease after treatment in the enzyme for 7 and 14 days while the water soluble partially esterified HA were degraded by the enzyme producing a sharp reduction of viscosity within minutes. These observations tend to suggest that the carboxylic groups in the beta-glucoronic acid unit are the activation centre of this enzyme and the total blockage of these groups can restrict the cleavage of beta (1-->4) glycoside bonds by this enzyme.

Biocompatible Materials↗
PubMed1991

Specific high performance liquid chromatographic determination of the molecular weight and concentration of hyaluronic acid in complex mixtures by labelled hyaluronate binding proteins.

A simple High performance liquid chromatographic (HPLC) method for the specific determination of the molecular weight and concentration of hyaluronic acid (HA) in complex mixtures has been developed. Hyaluronate-binding proteins isolated from bovine cartilage labelled by 125I or fluoresceinisothiocyanate were used as specific markers. The specific binding affinities of the markers were compared and were found to have association constants of 1.6 x 10(7) M-1 and 1.2 x 10(7) M-1 respectively. The HA levels and molecular weight distributions can be easily determined in the range 10-500 ng/mL in complex mixtures by the use of markers, molecular sieving HPLC columns and appropriate detectors. It has been demonstrated clearly that the method is useful for the highly specific determination of the parameters in complex biological samples such as serum and synovial fluids and is recommended for clinical applications.

Animals↗