Agitation plays an important role in the hyaluronic acid (HA) fermentation process. However, views about the effect of agitation on HA production remain controversial. We investigated the effect of agitation on cell growth and HA synthesis during HA fermentation process by using Computational Fluid Dynamics (CFD) technology. The results showed that the biomass and HA yield changed a little with the increase of impeller speed, but the HA molecular weight firstly increased and then decreased. The results of phase agitation control strategy demonstrated that the influence of agitation on the HA molecular weight mainly exhibited at the stage of HA synthesis. Moreover, the CFD simulation results indicated that when impeller speed increased, the mixing time reduced while the shear rate increased significantly. The removal of anchor could moderate the contradiction between the mixing time and shear rate, and finally the HA molecular weight increased by 23.9%. The results of this work could provide guidelines for optimizing the HA fermentation, as well as the bioreactor design and scaling up.
Bioreactors ; Fermentation ; Hyaluronic Acid ; biosynthesis ; chemistry ; Hydrodynamics ; Numerical Analysis, Computer-Assisted ; Shear Strength ; Streptococcus equi ; growth & development ; metabolism

Hyaluronic acid (HA) is an important biomaterial as the extracellular matrix in human body. We produced HA by fermentation of Streptococcus iniae (Strep.). Production of HA by Strep. was evaluated and further improved by strain mutation by ultraviolet. One strain with higher HA yield and lower content of protein was obtained. Its HA yield increased from (82.3±3.3) mg/L to (120±10.6) mg/L, and protein decreased from (0.178±0.011) mg/L to (0.032±0.017) mg/L. The molecular weight (MW) of HA yield from Strep. is about 3.0×10⁵ Da. Using the method of freezing and thawing, HA aqueous solution was transferred into hydrogel. This HA hydrogel, casted on sterilized non-woven fabric, was applied to repair rabbit skin with full-thickness defect. The preliminary results of the animal tests displayed that HA hydrogel obviously reduced the inflammation around the wound and promoted the skin regeneration comparing with the control tests.
Animals ; Biocompatible Materials ; Fermentation ; Hyaluronic Acid ; biosynthesis ; Hydrogels ; Molecular Weight ; Rabbits ; Regeneration ; Skin ; drug effects ; growth & development ; Streptococcus iniae ; metabolism ; Wound Healing

The effects of suppression of CD44 by CD44-specific antisense oligonucleotide on attachment of human trabecular meshwork cells to hyaluronic acid (HA) were observed and the possible relationship between CD44 and primary open-angle glaucoma (POAG) investigated. CD44-specific antisense oligonucleotide was delivered with cationic lipid to cultured human trabecular meshwork cells. The expression of CD44 suppressed by CD44-specific antisense oligonucleotide was detected by RT-PCR and Western blotting. The effect of CD44 suppression by specific antisense oligonucleotide on attachment of trabecular meshwork cells to HA was measured by MTT assay. Results showed that expression of CD44 was suppressed by CD44-specific antisense oligonucleotide. Antisense oligonucleotide also suppressed the adhesion of human trabecular meshwork cells to HA in a concentration dependent manner. It was concluded that attachment of human trabecular meshwork cells to HA was decreased when CD44 was suppressed by specific antisense oligonucleotide. CD44 might play a role in pathogenesis of POAG by affecting the adhesion of trabecular meshwork cells to HA.
Cell Adhesion ; Cells, Cultured ; Glaucoma, Open-Angle ; metabolism ; pathology ; Humans ; Hyaluronan Receptors ; biosynthesis ; genetics ; Hyaluronic Acid ; metabolism ; Oligonucleotides, Antisense ; pharmacology ; Trabecular Meshwork ; cytology

OBJECTIVETo investigate the differential expression of the hyaluronic acid synthase (HAS) family in human bladder transitional cell carcinoma (BTCC) and its potential clinical significance.

METHODSThe relative quantitative detection of the expression of HAS isoforms (HASs) was performed in 78 human BTCC tissues (mRNA & protein) and 12 normal human bladder mucosa (protein) by real-time RT-PCR and Western blot, and the results were statistically analyzed according to the clinical data.

RESULTSAll the BTCC tissues expressed three HAS isoform mRNA and protein, but to a different extent, as for mRNA, HAS3 > HAS2 > HAS1 (P < 0.001), with a significant difference in HAS1/HAS2, HAS1/HAS3 and HAS2/HAS3 (P = 0.003, < 0.001, 0.006, respectively). Among the proteins, the HAS2 expression was the highest, with a significant difference in HAS1/HAS2, and HAS2/HAS3 (P = 0.004, 0.001, respectively), but not in HAS1/HAS3. The elevation of HAS1 mRNA and protein expression was significantly related with the tumor malignancy, tumor initial onset/recurrence, T1/T2 and T1/T3-4 stags, and tumor grading (P = 0.02, < 0.001, 0.038, < 0.001; 0.025, 0.031, 0.023, 0.002; respectively). The HAS2 mRNA expression was significantly related with tumor size (diameter ≤ 3.0 cm/> 3.0 cm), tumor number (single or multiple), tumor initial onset/recurrence, T-staging, and histopathological differentiation (low grade/high grade) (P = 0.012, 0.004, < 0.001, < 0.001, < 0.001, respectively), but its protein expression was not significantly different in all subgroups except with the tumor size (mass diameter > 3.0 cm/≤ 3.0 cm). However, HAS3 mRNA and protein expression had no significant difference among all the subgroups. In normal human bladder mucosa, no HAS expressions were detected.

CONCLUSIONSThe abnormally high expression of the HASs further indicate the reliability of hyaluronan as a urinary marker for human BTCC. Compared with HAS1 and HAS3, HAS2 as a marker may have more usefulness in studies on human BTCC carcinogenesis or development. The high expression of HAS1 protein seems to play a more important role in the BTCC tumorigenesis, and may indicate a poor prognosis of the BTCC patients.

Biomarkers, Tumor ; Blotting, Western ; Carcinoma, Transitional Cell ; genetics ; metabolism ; Glucuronosyltransferase ; metabolism ; Humans ; Hyaluronan Synthases ; Hyaluronic Acid ; metabolism ; Neoplasm Recurrence, Local ; RNA, Messenger ; biosynthesis ; Reproducibility of Results ; Urinary Bladder Neoplasms ; genetics ; metabolism

Streptococcus zooepidemicus (SZ) is an aerotolerant bacteria and its ability to survive under reactive oxidant challenge raises the question of the existence of a defense system. Thus growth, hyaluronic acid (HA) and hydrogen peroxide (H2O2) production by SZ in the presence of increasing concentration of Mn2+ were studied. The results suggested that the tested strain supported growth and HA production in cultures treated with 1 and 10 mM of Mn2+ regardless of H2O2 presence in the medium. This showed that SZ have acquired elaborate defense mechanisms to scavenge oxygen toxicity and thus protect cells from direct and indirect effect of this radical. In contrast, cells treated with 25 mM Mn2+ were sensitive, in which, the HA production was reduced considerably. Thus showing that the oxygen scavenger systems of the cells may be fully saturated at this concentration.
Dose-Response Relationship, Drug ; Free Radical Scavengers/*metabolism ; Hyaluronic Acid/*biosynthesis ; Hydrogen Peroxide/*metabolism ; Magnesium/*pharmacology ; Reactive Oxygen Species/*metabolism ; Streptococcus equi/*drug effects ; Streptococcus equi/metabolism ; Superoxide Dismutase/physiology

Various kinds of glycosaminoglycans (GAGs) and proteoglycans (PGs) have been known to be involved in structural and space-filling functions, as well as many physiological regulations in skin. To investigate ultraviolet (UV) radiation-mediated regulation of GAGs and PGs in cultured human dermal fibroblasts, transcriptional changes of many types of PGs and GAG chain-synthesizing enzymes at 18 hr after 75 mJ/cm2 of UV irradiation were examined using quantitative real-time polymerase chain reaction methods. Hyaluronic acid synthase (HAS)-1, -2, and -3 and hyaluronidase-2 mRNA expressions were significantly increased by UV irradiation. Expressions of lumican, fibromodulin, osteoglycin, syndecan-2, perlecan, agrin, versican, decorin, and biglycan were significantly decreased by UV irradiation, while syndecan-1 was increased. Expressions of GAG chain-synthesizing glycosyltransferases, xylosyltransferase-1, beta1,3-glucuronyltransferase-1, beta1,4-galactosyltransferase-2, -4, exostosin-1, chondroitin polymerizing factor, and chondroitin sulfate synthase-3 were significantly reduced, whereas those of beta1,3-galactosyltransferase-6, beta1,4-galactosyltransferase-3, -7, beta-1,3-N-acetylglucosaminyltran sferase-2, and -7 were increased by UV irradiation. Heparanase-1 mRNA expression was increased, but that of heparanase-2 was reduced by UV irradiation. Time-course investigation of representative genes showed consistent results. In conclusion, UV irradiation may increase hyaluronic acid production through HAS induction, and decrease other GAG productions through downregulation of PG core proteins and GAG chain-synthesizing glycosyltransferases in cultured human dermal fibroblasts.
Cell Line ; Fibroblasts/metabolism/radiation effects ; Gene Expression Regulation/radiation effects ; Glucuronosyltransferase/genetics/radiation effects ; Glycosaminoglycans/*biosynthesis/chemistry ; Glycosyltransferases/genetics/*metabolism ; Humans ; Hyaluronic Acid/biosynthesis ; Hyaluronoglucosaminidase/genetics/radiation effects ; Polymerase Chain Reaction ; Proteoglycans/*biosynthesis/genetics/radiation effects ; RNA, Messenger/analysis/genetics ; Skin/*metabolism/radiation effects ; Transcription, Genetic/radiation effects ; *Ultraviolet Rays

BACKGROUNDGreat efforts have been made to search for the angiogenic inhibitors in avascular tissues. Several proteins isolated from cartilage have been proved to have anti-angiogenic or anti-tumour effects. Because cartilage contains a great amount of hyaluronic acid (HA) oligosaccharides and abundant HA binding proteins (HABP), therefore, we speculated that HABP might be one of the factors regulating vascularization in cartilage or anti-angiogenesis in tumours. The purpose of this research was to evaluate the effects of hyaluronan binding protein on inhibiting tumour growth both in vivo and vitro.

METHODSA unique protein termed human brain hyaluronan (HA) binding protein (b-HABP) was cloned from human brain cDNA library. MDA-435 human breast cancer cell line was chosen as a transfectant. The in vitro underlying mechanisms were investigated by determining the possibilities of MDA-435/b-HABP colony formation on soft agar, the effects of the transfectant on the proliferation of endothelial cells and the expression levels of caspase 3 and FasL from MDA-435/b-HABP. The in vivo study included tumour growth on the chorioallantoic membrane (CAM) of chicken embryos and nude mice.

RESULTSColony formation assay revealed that the colonies formed by MDA-435/b-HABP were greatly reduced compared to mock transfectants. The conditioned media from MDA-435/b-HABP inhibited the growth of endothelial cells in culture. Caspase 3 and FasL expressions were induced by MDA-435/b-HABP. The size of tumours of MDA-435/b-HABP in both CAM and nude mice was much smaller than that of MDA-435 alone.

CONCLUSIONSHuman brain hyaluronan binding protein (b-HABP) may represent a new kind of naturally existing anti-tumour substance. This brain-derived glycoprotein may block tumour growth by inducing apoptosis of cancer cells or by decreasing angiogenesis in tumour tissue via inhibiting proliferation of endothelial cells.

Animals ; Brain Chemistry ; Cartilage ; physiology ; Caspase 3 ; Caspases ; biosynthesis ; Cell Line, Tumor ; Chick Embryo ; Cloning, Molecular ; Endothelial Cells ; cytology ; Fas Ligand Protein ; Humans ; Hyaluronan Receptors ; genetics ; physiology ; Hyaluronic Acid ; metabolism ; Membrane Glycoproteins ; biosynthesis ; Mice ; Neoplasms, Experimental ; therapy ; Neovascularization, Pathologic ; prevention & control ; Transfection

OBJECTIVETo observe the influence of intra-articular injection of sodium hyaluronate (HA) on the mRNA expressions of matrix metalloproteinase-1,-3 (MMP-1,-3) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in cartilage and synovium of traumatic osteoarthritis (OA).

METHODSSixteen white rabbits underwent unilateral anterior cruciate ligament transection (ACLT) were divided into 2 groups randomly 5 weeks after transection. The experimental group rabbits received 0.3 ml of 1% HA by intra-articular injection once a week. Animals in the control group were treated under the same conditions using physiological saline. Ten weeks following surgery, cartilage and synovium were harvested. The mRNA expressions of MMP-1, MMP-3 and TIMP-1 were analyzed using reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSIn synovium, the mRNA expression of MMP-3 was suppressed in the HA injection group. HA treatment had no effect on the MMP-3 expression in cartilage. No significant difference of MMP-1 and TIMP-1 expressions in cartilage and synovium was found between the HA injection group and the control group.

CONCLUSIONSOne of the mechanisms of the therapeutic effect of HA may be the inhibition of expression of MMP-3 in synovium during early stage of traumatic OA.

Animals ; Anterior Cruciate Ligament ; drug effects ; metabolism ; Cartilage, Articular ; metabolism ; Hyaluronic Acid ; pharmacology ; Matrix Metalloproteinase 3 ; biosynthesis ; drug effects ; genetics ; Osteoarthritis, Knee ; metabolism ; pathology ; RNA, Messenger ; genetics ; Rabbits ; Reverse Transcriptase Polymerase Chain Reaction ; Synovial Membrane ; metabolism ; Tissue Inhibitor of Metalloproteinase-1 ; biosynthesis ; drug effects ; genetics