Glucosamine (GlcN), also called amino sugar, is a compound derived from the substitution of a hydroxyl group of glucose molecule with an amino group. GlcN finds a wide-range of applications in health food and pharmaceutical industries. In our previous research, a recombinant Escherichia coli-glms-gnal was constructed for the efficient production of GlcN and N-acetylglucosamine (GlcNAc), the latter can be readily deacetylated to GlcN under mild acidic conditions. However, the results indicated that the titer of GlcN and GlcNAc decreased significantly due to the transportation of GlcN and GlcNAc from the culture broth to the inside of cells. To alleviate or block the transportation process, nagE gene (encoding for the GlcNAc-specific transporter) and manX gene (encoding for the mannose transporter) were knocked out with the Red homologous recombination method, and two engineered strains, E. coli-glms-gna1-delta nagE (with nagE gene deletion) and E. coli-glms-gna1-delta nagE-delta manX (with nagE and manX genes deletion), were successfully constructed. The two strains were cultured in a 7-L fermentor for the production of GlcN and GlcNAc. The maximal GlcN concentration of control strain E. coli-glms-gnal reached 4.06 g/L, and the maximal GlcNAc concentration reached 41.46 g/L. The maximal GlcN and GlcNAc concentration of E. coli-glms-gna1-delta nagE reached 4.38 g/L and 71.80 g/L, respectively, which were 1.08-fold and 1.70-fold of those of E. coli-glms-gnal, respectively. The maximal GlcN and GlcNAc concentration of E. coli-glms-gnal-delta nagE-delta manX reached 4.82 g/L and 118.78 g/L, respectively, which were 1.20-fold and 2.86-fold of those of E. coli-glms-gnal, respectively. These results suggested that the deletion of nagE and manX could significantly increase the extracellular accumulation of GlcN and GlcNAc. The results obtained here maybe useful for the microbial GlcN production in an industrial scale.
Acetylglucosamine ; biosynthesis ; genetics ; Escherichia coli ; genetics ; metabolism ; Escherichia coli Proteins ; genetics ; Gene Knockout Techniques ; Glucosamine ; biosynthesis ; genetics ; Repressor Proteins ; genetics

OBJECTIVETo evaluate the transdermal permeability of glucosamine sulfate solution across ex vivo rabbit dermis under ultrasound and optimize the ultrasound conditions.

METHODSThe ultrasound-assisted transdermal permeation of glucosamine sulfate solution across ex vivo rabbit dermis was tested using a simple Franz diffuse. The transdermal permeation volume and rate were calculated by measuring the concentration of glucosamine sulfate in the receptor fluid with ultraviolet spectrophotometry, and the impact of different sound intensities, irradiation time and solution concentration on solution permeation was analyzed.

RESULTSAt the ultrasound intensity of 0.2 W/cm(2), the permeation volume and rate of glucosamine sulfate both reached the maximum; no glucosamine sulfate was detected in the receptor fluid after a 5-min ultrasound irradiation. The permeation volume and rate of glucosamine sulfate increased as the irradiation time prolonged and also with increased glucosamine sulfate concentration. The dorsal and lateral skin thickness (2.0∓0.1 and 1.2∓0.1 mm, respectively) did not significantly affect the transdermal permeation of glucosamine sulfate (P>0.05).

CONCLUSIONUltrasound irradiation at 1.0 MHz for over 5 min allows glucosamine sulfate to permeate rabbit dermis, and the volume and rate of permeation increase with the irradiation time and concentration of the solution and are not affected by variations of the dermal thickness.

Administration, Cutaneous ; Animals ; Dermis ; diagnostic imaging ; drug effects ; Glucosamine ; metabolism ; In Vitro Techniques ; Permeability ; Rabbits ; Skin Absorption ; Ultrasonics ; Ultrasonography

BACKGROUND: Glucosamine hydrochloride (GlcN·HCl) has been shown to inhibit cell growth and matrix synthesis, but not with N-acetyl-glucosamine (GlcNAc) supplementation. This effect might be related to an inhibition of critical growth factors (GF), or to a different metabolization of the two glucosamine derivatives. The aim of the present study was to evaluate the synergy between GlcN·HCl, GlcNAc, and GF on proliferation and cartilage matrix synthesis. METHOD: Bovine chondrocytes were cultivated in monolayers for 48 h and in three-dimensional (3D) chitosan scaffolds for 30 days in perfusion bioreactors. Serum-free (SF) medium was supplemented with either growth factors (GF) TGF-β (5 ng mL₋₁) and IGF-I (10 ng mL₋₁), GlcN·HCl or GlcNAc at 1mM each or both. Six groups were compared according to medium supplementation: (a) SF control; (b) SF + GlcN·HCl; (c) SF + GlcNAc; (d) SF + GF; (e) SF + GF + GlcN·HCl; and (f) SF + GF + GlcNAc. Cell proliferation, proteoglycan, collagen I (COL1), and collagen II (COL2) synthesis were evaluated. RESULTS: The two glucosamines showed opposite effects in monolayer culture: GlcN·HCl significantly reduced proliferation and GlcNAc significantly augmented cellular metabolism. In the 30 days 3D culture, the GlcN·HCl added to GF stimulated cell proliferation more than when compared to GF only, but the proteoglycan synthesis was smaller than GF. However, GlcNAc added to GF improved the cell proliferation and proteoglycan synthesis more than when compared to GF and GF/GlcN·HCl. The synthesis of COL1 and COL2 was observed in all groups containing GF. CONCLUSION: GlcN·HCl and GlcNAc increased cell growth and stimulated COL2 synthesis in long-time 3D culture. However, only GlcNAc added to GF improved proteoglycan synthesis.
Bioreactors ; Cartilage ; Cell Proliferation ; Chitosan ; Chondrocytes* ; Collagen ; Glucosamine* ; Insulin-Like Growth Factor I ; Intercellular Signaling Peptides and Proteins ; Metabolism ; Methods ; Perfusion ; Proteoglycans

The purpose of study was to explore the possible functions of Bcl-xL in the glucosamine sulfate-induced apoptosis of chronic myeloid leukemia K562 cells. Light microscopy and Wright-Giemsa staining were used to investigate the morphologic evidences for apoptosis of K562 cells induced by glucosamine sulfate (GS); immunofluorescence was used to observe the translocation of cathepsin D and cytochrome C during the apoptosis; Western blot was performed to detect the expression of Bcl-xL, Bid, Bax in K562 cells treated by GS. The results showed that many vacuoles were observed in the cytoplasma of the K562 cells treated by GS; fluorescent signals of cathepsin D and cytochrome were fransformed from granules to disperse form by using immunofluorescence; the expression of Bcl-xL was found down-regulated in K562 cells treated by GS, but not in the cells pre-treated with pepstatin A; the significant changes were not detected in expression of Bax and Bid protein before or after apoptosis. It is concluded that Bcl-xL protein may mediate relationship between cathepsin D and mitochondia pathway, Cathepsin D may play an important role in the GS inducing apoptosis of K562 cells through downregulation of Bcl-xL expression.
Apoptosis ; drug effects ; physiology ; BH3 Interacting Domain Death Agonist Protein ; metabolism ; Blotting, Western ; Cathepsin D ; metabolism ; Cytochromes c ; metabolism ; Fluorescent Antibody Technique ; Glucosamine ; pharmacology ; Humans ; K562 Cells ; bcl-2-Associated X Protein ; metabolism ; bcl-X Protein ; metabolism ; physiology

OBJECTIVES: To observe the effects of Yougui pill (Traditional Chinese Medicine) on the related factors of Wnt signal pathway of rats with knee osteoarthritis (KOA), and explore its protective mechanism. METHODS: Sixty SPF SD rats were randomly divided into the sham-operative group, model group, glucosamine sulfate group, high-dose, middle-dose, low-dose of Yougui pill treated group (=10). KOA model was established by modified Hulth method for six weeks. The rats in the high, middle and low-dose of Yougui pill group were treated with Yougui pills at the doses of 20,10 and 5 g/kg respectively by gastrogavage once a day for 8 weeks, while equal volume of normal saline was given to those in the sham and model control group and an equal volume of glucosamine sulfate (1.7 g/kg·d) was given to those in glucosamine sulfate group for 8 weeks. The knee joint was removed after the last dose of drug. The pathological changes of cartilaginous tissues were observed under a microscope. The mRNA levels of Dickkopf homolog 1(DKK1), Wnt induced secreted protein 1(WISP1), Wnt1, low density lipoprotein receptor related protein 5(LRP5) and beta -catenin in rats cartilaginous tissues were analyzed by using RT-PCR method, and the protein contents of DKK1, WISP1, Wnt1, LRP5 and beta-catenin in cartilaginous tissues were detected by Western blot. RESULTS: Compared with the sham group, the articular cartilage was severely damaged, the Mankin score was increased significantly (<0. 05), the mRNA and protein expression levels of DKK1 in cartilaginous tissue were markedly decreased(<0.05), while those of WISP, Wnt1, LRP5 and beta-catenin were increased significantly in model group(<0.05). Compared with model group, the articular cartilage lesions was light (<0.05), the Mankin Score was decreased significantly(<0.05), and the mRNA and protein levels of DKK1 in cartilaginous tissue were increased(<0.05), while those of WISP, Wnt1, LRP5 and beta-catenin were decreased in Yougui pill high-dose group and glucosamine sulfate group (<0.05). CONCLUSIONS Yougui pill has protective effects on the KOA by inhibiting the expressions of WISP, Wnt1, LRP5, beta-catenin and increasing the expression of DKK1 cytokine in the Wnt signaling pathway.
Animals ; CCN Intercellular Signaling Proteins ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Glucosamine ; pharmacology ; Intercellular Signaling Peptides and Proteins ; metabolism ; Osteoarthritis, Knee ; drug therapy ; Proto-Oncogene Proteins ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Wnt Signaling Pathway ; Wnt1 Protein ; metabolism ; beta Catenin ; metabolism

OBJECTIVE: To examine the expression of MMP-3 and TIMP-1 in the synovial fluid in knee joints with osteoarthritis before and after being treated with hyaluronic acid(HA), glucosamine sulfate(GS) and arthroscopic de bridment(AD), and to explore the therapeutic mechanism. METHODS: Sixty patients (64 knees) with osteoarthritis(OA) were randomly divided into HA group AD group and GS+AD group. Some patients from the HA group and the GS+HA group were selected, and served as HA' group and GS+HA' group. The expression of MMP-3 and TIMP-1 in the synovial fluid was measured by enzyme-linked immunosorbent assay (ELISA) before and after 4 week and 6 month therapy. RESULTS: The level of MMP-3 and the ratio of MMP-3/TIMP-1 in the synovial fluid decreased after being treated for 4 weeks, and the effect on MMP-3 and MMP-3/TIMP-1 lasted for 6 months in the HA group and the GS+HA groups. The levels of TIMP-1 increased significantly after being treated for 4 weeks only in the GS+HA group. The level of MMP-3 and the ratio of MMP-3/TIMP-1 in the synovial fluid decreased, but the level of TIMP-1 increased after being treated for 4 weeks, and the effect on MMP-3 and MMP-3/TIMP-1 lasted for 6 months. The level of MMP-3 and the ratio of MMP-3/TIMP-1 in the synovial fluid increased after being treated for 6 months compared with those for 4 weeks. The level of TIMP-1 increased in the GS group more than that in the HA group after being treated for 4 weeks. The level of TIMP-1 increased in the AD group more than that in the HA' group and the GS+HA' group after being treated for 4 weeks. CONCLUSION (1) HA, GS and AD all can decrease the level of of MMP-3 and the ratio of MMP-3/TIMP-1 in the synovial fluid in knee joints with OA. (2) The level of TIMP-1 in the synovial fluid has no difference before and after being treated with HA. The AD group and GS group can increase the level of TIMP-1, which indicates that the AD group or GS group might produce better therapeutic effect. (3) The level of TIMP-1 increased in the AD group is more than that in the HA' group and the GS+HA' group after being treated for 4 weeks, which indicates that the AD group might get better therapeutic effect than the other 2 groups. (4) One of the most important mechanisms of HA, GS and AD in treating OA might be attributed to the expression of MMPs and TIMPs in knee joints with OA.
Aged ; Debridement ; methods ; Female ; Glucosamine ; therapeutic use ; Humans ; Hyaluronic Acid ; therapeutic use ; Male ; Matrix Metalloproteinase 3 ; metabolism ; Middle Aged ; Osteoarthritis, Knee ; metabolism ; therapy ; Synovial Membrane ; metabolism ; Tissue Inhibitor of Metalloproteinase-1 ; metabolism

BACKGROUND/AIMS: The prevalence of peptic ulcer disease has not decreased mainly due to an increase in the use of NSAIDs. This study was conducted in order to determine whether a chronic NSAID-induced gastric inflammation model could be established by repeated administration of NSAID. METHODS: Indomethacin (10 mg/kg) was administered once per week for six weeks in 8- and 26-week rats and animals were sacrificed every week after administration. Gross ulcer index, histologic damage index, myeloperoxidase (MPO) activity, and mucus (glucosamine) levels were measured. Small bowel damage was also evaluated. RESULTS: Gross gastric damage index showed a peak level at three weeks and then decreased slowly in the 26-week indomethacin group. Gastric mucosal glucosamine level increased in both the 8-week (p=0.038) and 26-week groups (p=0.007). In addition, gastric mucosal MPO level decreased in the 8-week group (p=0.018) but did not show a decrease in the 26-week group. Small bowel damage began to occur at three weeks during the schedule and eight of 36 rats (22.2%) died due to perforation or peritonitis of the small bowel in the 8- and 26-week indomethacin groups, respectively. CONCLUSIONS: Due to gastric adaptation and small bowel damage, repeated administration of NSAID to experimental animals may not be an adequate method for establishment of the chronic gastric inflammation model.
Animals ; Anti-Inflammatory Agents, Non-Steroidal/*toxicity ; Disease Models, Animal ; Gastric Mucosa/*drug effects/enzymology/pathology ; Glucosamine/metabolism ; Indomethacin/*toxicity ; Intestine, Small/*drug effects/pathology ; Male ; Peroxidase/metabolism ; Rats ; Rats, Sprague-Dawley ; Time Factors

BACKGROUND/AIMS: The prevalence of peptic ulcer disease has not decreased mainly due to an increase in the use of NSAIDs. This study was conducted in order to determine whether a chronic NSAID-induced gastric inflammation model could be established by repeated administration of NSAID. METHODS: Indomethacin (10 mg/kg) was administered once per week for six weeks in 8- and 26-week rats and animals were sacrificed every week after administration. Gross ulcer index, histologic damage index, myeloperoxidase (MPO) activity, and mucus (glucosamine) levels were measured. Small bowel damage was also evaluated. RESULTS: Gross gastric damage index showed a peak level at three weeks and then decreased slowly in the 26-week indomethacin group. Gastric mucosal glucosamine level increased in both the 8-week (p=0.038) and 26-week groups (p=0.007). In addition, gastric mucosal MPO level decreased in the 8-week group (p=0.018) but did not show a decrease in the 26-week group. Small bowel damage began to occur at three weeks during the schedule and eight of 36 rats (22.2%) died due to perforation or peritonitis of the small bowel in the 8- and 26-week indomethacin groups, respectively. CONCLUSIONS: Due to gastric adaptation and small bowel damage, repeated administration of NSAID to experimental animals may not be an adequate method for establishment of the chronic gastric inflammation model.
Animals ; Anti-Inflammatory Agents, Non-Steroidal/*toxicity ; Disease Models, Animal ; Gastric Mucosa/*drug effects/enzymology/pathology ; Glucosamine/metabolism ; Indomethacin/*toxicity ; Intestine, Small/*drug effects/pathology ; Male ; Peroxidase/metabolism ; Rats ; Rats, Sprague-Dawley ; Time Factors

Glucosamine, a naturally occurring amino monosaccharide, has been reported to play a role in the regulation of apoptosis more than half century. However the effect of glucosamine on tumor cells and the involved molecular mechanisms have not been thoroughly investigated. Glucosamine enters the hexosamine biosynthetic pathway (HBP) downstream of the rate-limiting step catalyzed by the GFAT (glutamine:fluctose-6-phosphate amidotransferase), providing UDP-GlcNAc substrates for O-linked beta-N-acetylglucosamine (O-GlcNAc) protein modification. Considering that O-GlcNAc modification of proteasome subunits inhibits its activity, we examined whether glucosamine induces growth inhibition via affecting proteasomal activity. In the present study, we found glucosamine inhibited proteasomal activity and the proliferation of ALVA41 prostate cancer cells. The inhibition of proteasomal activity results in the accumulation of ubiquitinated proteins, followed by induction of apoptosis. In addition, we demonstrated that glucosamine downregulated proteasome activator PA28gamma and overexpression of PA28gamma rescued the proteasomal activity and growth inhibition mediated by glucosamine. We further demonstrated that inhibition of O-GlcNAc abrogated PA28gamma suppression induced by glucosamine. These findings suggest that glucosamine may inhibit growth of ALVA41 cancer cells through downregulation of PA28gamma and inhibition of proteasomal activity via O-GlcNAc modification.
Acetylglucosamine/chemistry/metabolism ; Alloxan/pharmacology ; Apoptosis/*drug effects ; Autoantigens/genetics/*metabolism ; Cell Line, Tumor ; Cell Proliferation/*drug effects ; Gene Expression Regulation, Neoplastic ; Glucosamine/*pharmacology ; Humans ; Male ; Phosphorylation ; Prostatic Neoplasms/*enzymology ; Proteasome Endopeptidase Complex/*antagonists & inhibitors/genetics/metabolism ; RNA, Small Interfering/genetics ; Ubiquitinated Proteins/metabolism

The growth inhibitory effects of D-glucosamine hydrochloride (GlcNH(2).HCl), D-glucosamine (GlcNH(2)) and N-acetyl glucosamine (NAG) on human hepatoma SMMC-7721 cells in vitro were investigated. The results showed that GlcNH(2).HCl and GlcNH(2) resulted in a concentration-dependent reduction in hepatoma cell growth as measured by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. This effect was accompanied by a marked increase in the proportion of S cells as analyzed by flow cytometry. In addition, human hepatoma SMMC-7721 cells treated with GlcNH(2).HCl resulted in the induction of apoptosis as assayed qualitatively by agarose gel electrophoresis. NAG could not inhibit the proliferation of SMMC-7721 cells. GlcNH(2).HCl exhibited antitumor activity against Sarcoma 180 in Kunming mice at dosage of 125-500 mg/kg, dose of 250 mg/kg being the best. GlcNH(2).HCl at dose of 250 mg/kg could enhance significantly the thymus index, and spleen index and could promote T lymphocyte proliferation induced by ConA. The antitumor effect of GlcNH(2).HCl is probably host-mediated and cytocidal.
Animals ; Antineoplastic Agents ; therapeutic use ; Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; DNA ; metabolism ; DNA Fragmentation ; drug effects ; Glucosamine ; analogs & derivatives ; therapeutic use ; Humans ; Liver Neoplasms ; drug therapy ; pathology ; Male ; Mice ; Sarcoma 180 ; drug therapy