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Measurement of serum hyaluronic acid level during the perioperative period of liver resection for evaluation of functional liver reserve.

BACKGROUND AND AIM: The serum hyaluronic acid (HA) concentrations reflect the degree of hepatic fibrosis and sinusoidal endothelial cell damage. The HA concentrations were examined to evaluate liver damage during the perioperative period of hepatectomy. METHODS: The HA level of serum samples from 79 patients who underwent a hepatectomy was measured, and the results were compared to conventional liver function tests, the degree of fibrosis, liver regeneration and complications. RESULTS: Hyaluronic acid concentrations correlated with the severe fibrosis or histological activity index, and also correlated with liver function tests including transaminase level, platelet counts, prothrombin time activity, indocyanine green retention rate at 15 min (ICG R15), liver activity at 15 min by technetium-99m galactosyl human serum albumin scintigraphy (LHL 15), and portal pressure. The HA level postoperatively correlated with liver function, especially with total bilirubin. Hyaluronic acid levels at day 28 postoperatively correlated with ICG R15 and LHL 15. The hyaluronic acid level before surgery and at day 28 postoperatively correlated with the regeneration of remnant liver in major hepatectomy. The HA levels were significantly higher in patients with hepatic failure or prolonged ascites. CONCLUSION: Our results indicate that the measurement of the HA level is useful for monitoring liver damage or predicting complications associated with liver surgery.

Adult↗

Hyaluronic acid in cutaneous intrinsic aging.

BACKGROUND: In elderly individuals all components of the skin and subcutaneous tissue undergo histologic and ultrastructural changes. The turgidity of the dermis appears decreased, presumably due to altered patterns and levels of glycosaminoglycans (GAGS), especially hyaluronic acid and dermatan sulfate that are the most common. A linear, age-related decrease in the content of GAGS (mainly hyaluronic acid) has been hypothesized in human aged skin. METHODS: We used the cationic dye Alcain Blue to selectively stain hyaluronic acid within the dermis in old and young subjects to compare ultrastructurally its topography and variations with age. RESULTS: We demonstrated a progressive reduction in the number of electron-dense granules of hyaluronic acid and of their filaments until they were completely absent in subjects aged 60. CONCLUSIONS: We propose that the variations of the levels of hyaluronic acid in the dermis in aging could account for some of the most striking alterations of the aged skin, including decreased turgidity, less support for microvessels, wrinkling, and altered elasticity.

Adult↗

Effect of 4-methylumbelliferone on cell-free synthesis of hyaluronic acid.

Human skin fibroblasts were cultured in the presence of 0.5 mM 4-methylumbelliferone for 12 h, and cell-free synthesis of hyaluronic acid was performed using membrane-rich fraction from the cells. The preincubation of the cells with 4-methylumbelliferone reduced hyaluronic acid synthesis to 15% of that of non-preincubated cells, although its chain length was not changed. On the other hand, without preincubation of the cells with 4-methylumbelliferone, hyaluronic acid synthesis was not changed even when 4-methylumbelliferone was added directly to the reaction mixture. These results suggest that 4-methylumbelliferone represses the expression of hyaluronic acid synthase on the cell surface.

Cell Membrane↗

[Effectiveness of intra-articular application of hyaluronic acid on early forms of femoropatellar arthrosis--an experimental study in dogs].

PURPOSE: We investigated the effects of intraarticularly applied hyaluronic acid on the cartilage-integrity with early-forms of retropatellar cartilage degeneration (chondromalacia patellae) in dogs. METHODS: We used the Pond-Nuki model (tenotomy and resection of the anterior cruciate ligament = ACL) in 27 dogs (foxhounds) (3 groups of 9 animals) PILOT STUDY: ACL-tenotomy and resection, no therapy, specimens retrieval after 3, 6, 12 weeks (3 animals each period). VERUM: ACL-tenotomy and resection, hyaluronic acid (start after 3, 6, 12 weeks), 5 injections in 4 weeks, specimens retrieval after 5 weeks following final injection (12, 15, 21 weeks postoperatively, 3 dogs each period). PLACEBO: same procedure as verum, but saline-injections. Specimens were taken from the medial/lateral patellar pole from both, the operated and the normal knee and examined histologically using various staining methods (HE, Azan, Toluidin, Masson-Goldner, Safranin-O). A modified Mankin score was used to grade cartilage degeneration. RESULTS: Our results demonstrate that the Pond-Nuki model is suitable to experimentally induce chondromalacia patellae. There were significantly less degenerative cartilage changes in the knees treated with hyaluronic acid compared to the placebo-group. CONCLUSION: Our results let assume that hyaluronic acid could be indicated i.e. after arthroscopically diagnosed early cartilage-degeneration, the final conclusions concerning the actual mechanisms and therapeutical effectiveness need however further prospective clinical and experimental investigations.

Animals↗

Levels of [3H]glucosamine incorporation into hyaluronic acid by fibroblasts is modulated by culture conditions.

Tissue culture conditions can modulate apparent levels of incorporation of the radiolabeled precursor [3H]glucosamine into hyaluronic acid in cells. A careful study was made on the effects of culture conditions on human skin fibroblasts. A newly described technique to measure hyaluronic acid was utilized based on incorporation of [3H]glucosamine into cetylpyridinium chloride-precipitable hyaluronidase-digestible material. The precipitate was collected on glass fiber filters using a manifold suction apparatus. A six-fold greater level of incorporation occurred in rapidly growing preconfluent than in confluent fibroblasts. Ascorbic acid stimulated incorporation with a maximum at 25 micrograms/ml. The same ascorbic acid optimum was observed for collagen prolylhydroxylation. When beta-hydroxybutyrate was used as an energy source instead of D-glucose, a 3.5-fold increase in levels was observed. All tissue-culture media examined supported comparable levels of incorporation, except for Roswell Park Memorial Institute Media-1640, in which cells had only half the level. Fetal calf serum supported high levels of incorporation in a dose-dependent manner, while newborn calf and calf sera supported much lower levels of incorporation. Under serum-free conditions, lactalbumin hydrolysate was best able to support incorporation of hyaluronic acid. In the search for mechanisms that modulate hyaluronic acid, it is critical to consider the tissue culture conditions under which incorporation of radiolabeled precursors are being examined.

3-Hydroxybutyric Acid↗

Hyaluronic acid production by irradiated human synovial fibroblasts.

Radioactive particles as well as X-irradiation from an external source have been used in the treatment of rheumatoid arthritis, osteoarthritis, and ankylosing spondylitis. In order to clarify effects of ionizing irradiation on synovial cells, radioactive gold (198Au) and yttrium (90Y) were added to fibroblast cultures derived from human synovial membranes. Other cultures were irradiated by a Picker X-ray machine. Fibroblast growth and hyaluronic acid production were measured. Radioactive gold and yttrium particles induced a significant increase of hyaluronic acid synthesis rate (pg/cell/day) and inhibited fibroblast growth. Fibroblasts continued to overproduce hyaluronic acid and to show growth inhibition 3 weeds after irradiation with radioactive gold. Hydrocortisone inhibited hyaluronic acid overproduction induced by radioactive gold. Overproduction of hyaluronic acid induced by the X-ray machine was inhibited by hydrocortisone, actinomycin-D, and cycloheximide. Fibroblasts derived from normal and rheumatoid patients responded similarly to ionizing irradiation.

Fibroblasts↗

An autologous cell hyaluronic acid graft technique for gingival augmentation: a case series.

BACKGROUND: An autologous cell hyaluronic acid graft was used for gingival augmentation in mucogingival surgery. METHODS: Seven sites from 6 patients were used in this study. Five patients (5 sites) needed gingival augmentation prior to prosthetic rehabilitation, and one patient (2 sites) needed augmentation because of pain during daily toothbrushing. Full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), probing depth (PD), and clinical attachment level (CAL) were recorded for the sites at baseline and 3 months after surgery. The amount of keratinized tissue (KT) was measured in the mesial, middle, and distal sites of each involved tooth. A small 2 x 1 x 1 mm portion of gingiva (epithelium and connective tissue) was removed from each patient, placed in a nutritional medium, and sent to the laboratory. The gingival tissue was processed: keratinocytes and fibroblasts were separated and only fibroblasts were cultivated. They were cultured on a scaffold of fully esterified benzyl ester hyaluronic acid (HA) and returned to the periodontal office under sterile conditions. During the gingival augmentation procedure, the periosteum of the selected teeth was exposed, and the membrane containing cultivated fibroblasts was adapted to and positioned on the site. RESULTS: Three months after surgery, an increased amount of gingiva was obtained, and the histological examination revealed a fully keratinized tissue on all the treated sites. CONCLUSION: Tissue engineering technology using an autologous cell hyaluronic acid graft was applied in gingival augmentation procedures and provides an increase of gingiva in a very short time without any discomfort for the patient.

Absorbable Implants↗

Suppression of lens stalk cell apoptosis by hyaluronic acid leads to faulty separation of the lens vesicle.

How the lens vesicle separates normally from the surface ectoderm has not been adequately explained. Apoptosis is an important mechanism that induces tissue development and morphogenesis by physiological cell death during normal development, and hyaluronic acid has been shown to regulate the apoptotic process in various tissues. To elucidate the normal and abnormal processes of lens vesicle separation, we investigated the distribution of apoptotic cells and hyaluronic acid in normal and abnormal lens vesicle development. The offspring from pregnant C57BL/6NJcl mice were removed by laparotomy on days 9, 10, 11, 12, 13, 14, 15, 16 or 18 of gestation. Tissue blocks of the eyes were fixed in 4% paraformaldehyde solution and embedded in paraffin wax. Serial sections of the eye were cut, and sections containing normal lens tissues and spontaneously occurring faulty separation of the lens vesicle were chosen for subsequent procedures. These sections were stained either with TUNEL method for detection of apoptosis or with biotinylated hyaluronic acid binding protein (HABP) for hyaluronic acid. Then TUNEL-positive and HABP-positive reactions in the lens tissues were examined by light microscopy. In normal eye development, the lens stalk connecting the surface ectoderm with the lens vesicle was observed from day 11 through day 12 of gestation, and the lens stalk completely disappeared on day 13 of gestation in this strain. In normally regressive lens stalk, several TUNEL-positive cells were identified, and no positive staining for HABP was seen. However, in spontaneously occurring persistent lens stalk tissues on days 14, 15, 16 and 18 of gestation, no TUNEL-positive cells were detectable, and evident HABP-positive reactions were seen. In eyes on day 12 of gestation with possibly presumed faulty separation of the lens vesicle, no TUNEL-positive cells were detectable and evident HABP-positive reactions were seen in the lens stalk areas. The results indicated that cell death by apoptosis is anatomically closely associated with, appears to be essential for normal regression of the lens stalk, and its failure to occur leads to faulty separation of the lens vesicle. In addition, excessive hyaluronic acid in the lens stalk area may be a possible cause of the lack of apoptosis, inducing its faulty separation.

Animals↗

Effects of hyaluronic acid on peripheral nerve scarring and regeneration in rats.

The purpose of this experimental study was to investigate the effects of topical applications of hyaluronic acid on peripheral nerve scarring and regeneration in an adult rat model. After the right sciatic nerves of 48 rats were transected and immediately repaired, nerves were randomly divided into two groups. Nerves to which were applied hyaluronic acid comprised the experimental group, and nerves to which were applied saline comprised the control group. Perineural scarring was evaluated at 4 and 12 weeks macroscopically and histologically. Nerves treated with hyaluronic acid demonstrated significant reduction in perineural scar thickness (P < 0.05, Student's t-test). Histomorphologic nerve analysis, electrophysiologic studies, muscle mass evaluation, and serial functional walking-track analysis were performed for evaluation of peripheral nerve regeneration at 12 weeks. The results showed better conduction velocities, increased axon-fiber diameter, and faster functional recovery in hyaluronic acid-treated nerves (P < 0.05, Student's t-test). In conclusion, hyaluronic acid appears to be effective in preventing perineural scar formation, resulting in enhancement of peripheral nerve regeneration.

Administration, Topical↗

Adhesion molecules on intermediate TCR cells. II. Hepatoprotective effects of hyaluronic acid on acute liver injury.

The liver is a major organ wherein extrathymic T cells and NK cells exist in mice. Due to their unique properties, i.e., extrathymic T cells are TCR (or CD3)-intermediate+ IL-2R beta+ (herein termed intermediate TCR cells) and NK cells are TCR(-)IL-2R beta+, they are easily distinguished from the other lymphocyte subsets by using mAbs in conjunction with immunofluorescence tests. They were recently found to express a higher level of CD44 antigen, which is a ligand for hyaluronic acid, than that of another T cell subset (i.e., thymus-derived T cells or bright TCR cells). Since an intravenous administration of hyaluronic acid was also found to reduce the number of intermediate TCR cells and NK cells in the liver, we examined whether hyaluronic acid had a hepatoprotective effect on acute liver injury. Such injury was induced by LPS injection in mice pretreated with Propionibacterium acnes 1 week earlier. When a single dose of hyaluronic acid was given to these mice 12 hr before LPS injection, a prominent hepatoprotective effect was observed in terms of decreases of mortality (up to 50%), lymphocyte infiltration of the liver, serum transaminase levels, and tissue damage. At this time, liver mononuclear cells isolated from the treated mice showed decreased levels of cytokine production such as TNF and IL-1. These results reveal that intermediate TCR cells and NK cells in the liver actually adhere the sinusoid walls by means of an interaction of CD44 molecules and hyaluronic acid even in the case of acute liver injury. It suggests a possible therapeutic effect of the administration of hyaluronic acid in acute liver injury by eliminating the effector cells and cytokine-producing cells from the liver.

Adjuvants, Immunologic↗

Mesothelial cell-associated hyaluronic acid promotes adhesion of endometrial cells to mesothelium.

OBJECTIVE: To evaluate the role of hyaluronic acid in the attachment of endometrial cells to mesothelium. DESIGN: In vitro study of adhesion of endometrial stromal and epithelial cells to mesothelial cells. SETTING: University medical center. PATIENT(S): Reproductive-age women without endometriosis undergoing surgery for benign conditions. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The effect of hyaluronidase treatment of mesothelial cells or endometrial cells on adhesion of (51)Cr labeled endometrial stromal and epithelial cells to monolayers of mesothelium was evaluated. The expression of CD44, the hyaluronate receptor, was evaluated by western blot. RESULT(S): Hyaluronidase pretreatment of mesothelial cells decreased the binding of endometrial stromal and epithelial cells to mesothelium by 39% (P< .02) and 31% (P< .03), respectively. There was no effect on endometrial cell binding to mesothelial cells or to collagen IV when the endometrial cells were pretreated with hyaluronidase. CD44 expression by endometrial stromal and epithelial cells was demonstrated by western blot. CONCLUSIONS: This study demonstrates that mesothelial cell-associated hyaluronic acid is involved in attachment of endometrial stromal and endometrial epithelial cells to the mesothelium. We hypothesize that binding of hyaluronic acid by endometrial cells is involved in the pathogenesis of the early endometriotic lesion.

Cell Adhesion↗

Effect of oxygen-derived free radicals on hyaluronic acid.

To investigate possible mechanisms of hyaluronic acid depolymerization, superoxide anion and other secondary oxygen-derived free radicals were generated in vitro and allowed to act upon a hyaluronate substrate. Superoxide, generated either enzymatically with xanthine oxidase or by stimulation of polymorphonuclear leukocytes, reduced the viscosity of hyaluronate solutions dramatically while the chromatographic profiles of the glycosaminoglycan shifted toward lower molecular weights. Superoxide-treated hyaluronate also became susceptible to further degradation by beta-N-acetylglucosaminidase A. Experiments with scavengers of various toxic oxygen-derived free radicals clearly implicated these reactants as mediators of hyaluronate depolymerization. Generation of superoxide by leukocytes in vivo may account for the loss of synovial fluid viscosity that accompanies inflammatory joint disease.

Copper↗

Network formation of low molecular weight hyaluronic acid derivatives.

The oscillatory and steady shear rheological properties of the benzyl esters of hyaluronic acid (HA), partially esterified (Hyaff 11p50), at low molecular weight (150 kDa) were evaluated and compared to the properties of HA at the same molecular weight. At concentrations up to 40 mg cm(-3) both Hyaff 11p50 solutions and HA solutions, behaved as viscous fluids. At higher concentrations, HA ester solutions exhibited an elastic response typical of weak gels, whereas HA exhibited a viscous behaviour. A solid-like response was also observed by lowering the temperature. These results indicate that hyaluronic acid ester solutions can form a weak gel network. The rheological properties of HA derivatives changed significantly compared to HA solutions. The improved elasticity and residence times of these solutions expand the possible applications of hyaluronic acid in the biomedical field.

Dose-Response Relationship, Drug↗

Cell adhesion molecules and hyaluronic acid as markers of inflammation, fibrosis and response to antiviral therapy in chronic hepatitis C patients.

OBJECTIVE: Cell adhesion molecules (intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1)) and hyaluronic acid, markers of inflammation and fibrosis were monitored in hepatitis C patients to determine whether changes in plasma levels, during antiviral treatment, can predict long-term response to therapy. METHODS: In 55 patients with chronic hepatitis C virus (HCV), 33 treated with interferon (IFN) and 22 treated with IFN + ribavirin, sera was collected prior to treatment, at 3 + 6 months of therapy and 6 months post-treatment. Levels of ICAM-1, VCAM-1 and hyaluronic acid were correlated with alanine aminotransferase levels, HCV-RNA-polymerase chain reaction status and histological fibrosis scoring. RESULTS: A decrease in ICAM-1 levels at 3 and 6 months of therapy, compared with pretreatment levels, was observed in responders to IFN + ribavirin therapy but this decrease in ICAM-1 levels was not evident following cessation of treatment. Hyaluronic acid levels, in both treatment groups, did not differ significantly between responders and non-responders. Hyaluronic acid levels did correlate, significantly, with degree of fibrosis whereas VCAM-1 levels were marginally increased only in patients with moderate (grade III) fibrosis. CONCLUSIONS: Monitoring of VCAM-1 and hyaluronic acid, during antiviral therapy, does not differentiate between responders and non-responders. A decrease in ICAM-1 levels during IFN + ribavirin treatment is associated with response to therapy, and its efficacy in predicting long-term response should be further substantiated.

Adult↗

Non-animal stabilized hyaluronic acid: a new formulation for the treatment of osteoarthritis.

Hyaluronic acid (HA) is a major component of human synovial fluid, providing the rheologic properties (elasticity and viscosity) that enable the synovial fluid to perform lubricating and shock-absorbing functions within the healthy joint. Over the last 2 decades, HA preparations have become established in intra-articular therapy of osteoarthritis (OA), particularly OA of the knee. Existing HA preparations, both cross-linked and non-cross-linked, are all administered by courses of multiple injections, and all have been associated with variable success rates. The clinical profile of an HA preparation is inextricably linked to the product's physicochemical properties. For example, the molecular structure of the HA affects the intra-articular residence time, which should in turn influence the duration of action post-injection. Non-animal stabilized hyaluronic acid (NASHA) is a new-generation HA preparation, produced wholly from non-animal sources. NASHA is stabilized using a carefully controlled cross-linking process, which increases the intra-articular residence time from hours to weeks. This facilitates single-injection treatment for OA without affecting the biocompatibility of HA. This review evaluates the properties of NASHA, including the available clinical data, in the context of previously developed HA preparations.

Adjuvants, Immunologic↗

Effects of hyaluronic acid on the development of 1- and 2-cell porcine embryos to the blastocyst stage in vitro.

The purpose of this study was to evaluate the ability of hyaluronic acid to improve the development of 1- and 2-cell porcine embryos to the blastocyst stage in a simple medium. In Experiment 1, we confirmed the ability of Whitten's medium supplemented with 15 mg/ml BSA to support the development of porcine embryos to the blastocyst stage under our experimental conditions. Embryos collected from oviducts were cultured at 38.5 degrees C in an atmosphere of 5% CO(2) in humidified air up to 6 d. After 2 d of culture, 82 and 78% of embryos reached the 4-cell stage or beyond in TCM199 supplemented with 10% fetal calf serum (FCS) and in Whitten's medium with BSA, respectively. However, no embryo developed to the morula stage in TCM199 after 6 d of culture. On the other hand, 26 and 15% of embryos developed to the morula and the blastocyst stage in Whitten's medium, respectively. In Experiment 2, we determined whether supplementation of hyaluronic acid in Whitten's medium would improve the development of porcine embryos to the blastocyst stage. After 6 d of culture, development of the embryos to the blastocyst stage was best supported in Whitten's medium with 4 mg/ml BSA and 0.5 mg/ml hyaluronic acid (70%). The proportion of degenerated embryos was lower in the presence than in the absence of hyaluronic acid. These results indicate that the supplementation of Whitten's medium with hyaluronic acid improves the development of 1- and 2-cell porcine embryos to the blastocyst stage.

Journal Article↗