Quantitative determination of chondroitin sulfate with various molecular weights in raw materials by pre-column derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate

A simple and reliable HPLC method was developed for quantification of chondroitin sulfate (CS). The procedure is based on precolumn hydrolysis of CS to liberate galactosamine and subsequent derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. Hydrolysis and derivatization conditions were optimized. A linear correlation coefficient of 0.9999 was calculated within the range of 10-1500 μg/mL from the standard curve. The method produces good precision and good accuracy (100.75 % recovery). An advantage over other common methods is its ability to quantify CS of all molecular weights and structures, as evidenced by the determination of CS fractions with narrow molecular weight distributions obtained through depolymerization by different methods, while enzymatic HPLC was proven to be infeasible. Extraction recoveries of CS from monosaccharide mixed samples were > 93 %. The reliability was also validated by a small difference (-1.95 % to 4.12 %) relative to enzymatic HPLC results in analysing representative CS samples of different animal origins and suppliers.

Galactosamine-modified PEG-PLA/TPGS micelles for the oral delivery of curcumin

In this study, galactosamine-modified poly(ethylene glycol)-poly(lactide) (Gal-PEG-PLA) polymers were synthesized and Gal-PEG-PLA/D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) micelles named as GPP micelles were designed to promote the oral absorption of a hydrophobic drug, curcumin (CUR). CUR-loaded Gal-PEG-PLA/TPGS micelles (CUR@GPP micelles) were fabricated using the thin-film dispersion method. CUR@GPP micelles had a size of about 100 nm, a near-neutral zeta potential, drug loading (DL) of 14.6%, and sustained release properties. GPP micelles with high Gal density (GPP3 micelles) were superior in facilitating uptake in epithelial cells and improving intestinal permeation. In situ intestinal absorption studies suggested that the jejunum and ileum were the best absorption segments in the intestinal tract. Additionally, biodistribution results revealed that GPP3 micelles could be remarkably taken up by the jejunum and ileum. Pharmacokinetics revealed that the maximum plasma concentration (C_max) and the area under the plasma concentration-time curve from 0 to 24 h (AUC_0-24) for CUR@GPP3 micelles were both significantly increased, and that the relative bioavailability of CUR@GPP3 micelles to CUR-loaded mPEG-PLA/TPGS micelles (CUR@PP micelles) was 258.8%. Furthermore, CUR-loaded micelles could reduce damage to the liver and intestinal tissues. This study highlights the importance of Gal content in the design of targeting nanocarrier Gal-modified micelles, which have broad prospects for oral delivery of hydrophobic drugs. Therefore, they could serve as a promising candidate for targeted delivery to the liver.

Water-soluble galactosamine derivative of β-cyclodextrin as protective ligand and targeted carrier for delivery of toxic anthracycline drug

β-cyclodextrin modified with an electron-rich aromatic triazole linker and targeting moiety (galactosamine) was synthesized and studied as a carrier for the anticancer drug, doxorubicin (DOX), with the aim of targeting the pathological cells, reducing the cardiotoxic side effects and increasing the binding of the drug to DNA. The β-cyclodextrins modified with galactosamine (βCDGAL) are non-toxic and highly soluble in aqueous medium compared to the native βCD and βCD modified only with aromatic moiety, such as triazole linker. Molecular modelling and NMR study gave a deeper insight into the ligand structure, providing an explanation for its increased solubility, and the drug-ligand interactions. The triazole linker strengthened the drug binding and introduced pH dependence of the complex stability constants for βCDGAL derivative, as confirmed by the voltammetry measurements. Spectroscopic studies have shown that entrapment of the DOX in βCDGAL cavity reduces the stability constant of the DOX:Fe(III) complex responsible for the production of cardiotoxic reactive oxygen species and additionally supports the binding of the drug to the double strand DNA. The MTT assay and confocal microscopy results showed that despite encapsulation of the drug in the cyclodextrin molecule, its cytotoxic effect on the liver cancer cell line (HepG2) is comparable to that of the free, non-protected drug.

Inhibition of Bruton tyrosine kinase by acalabrutinib dampens lipopolysaccharide/galactosamine-induced hepatic damage

Bruton tyrosine kinase (BTK) sits at the crossroads of adaptive and innate immunities. Nevertheless, the detailed role of BTK activation in hepatic inflammatory disorders is still elusive to date. Accordingly, we investigated the impact of blocking BTK activation by acalabrutinib (ACB) on lipopolysaccharide/galactosamine (LPS/D-GaIN)-induced deleterious manifestations in the liver. This was achieved by pretreating mice with ACB (6, 12 or 24 mg/kg, oral) 2 h before challenge with LPS/D-GaIN (70 μg/kg and 700 mg/kg, respectively, i.p.) for 6 h. The results showed that ACB (6 and 12 mg/kg) (i) curbed LPS/D-GaIN-induced rise in biochemical (serum ALT, AST and LDH) and histological (necrosis, degeneration and congestion scores) indices of hepatocellular injury; (ii) attenuated LPS/D-GaIN-induced elevation in parameters of hepatocellular apoptosis (cleaved caspase 3) and proliferation (PCNA); and (iii) importantly, mitigated LPS/D-GaIN-induced recruitment and infiltration of the inflammatory cells to the liver evidenced by lowering elevated serum MCP-1 concentration and hepatic F4/80 immunostaining. These effects were linked to ACB dose-dependent inhibition of NF-κB nuclear translocation that subsequently reduced LPS/D-GaIN-mediated release of TNF-α, IL-1β and IL-22 in the blood circulation. However, a dose of 12 mg/kg of ACB elevated the hepatic TNF-α, IL-1β and IL-22 concentrations that arose from a compensatory activation of ERK and JNK. Inhibition of BTK also attenuated LPS/D-GaIN-induced overexpression of CD98, which is another contributor alongside cytokines for monocyte recruitment. Therapeutically, targeting BTK by ACB is an efficient approach for hitting multiple points with one agent that can dampen hepatocellular injury, death, immune cell recruitment and inflammation cascade.

Preparation, Physicochemical Characterization and Anti-Fungal Evaluation of Amphotericin B-Loaded PLGA-PEG-Galactosamine Nanoparticles

Purpose: The present study aimed to formulate PLGA and PLGA-PEG-galactosamine nanoparticles (NPs) loaded with amphotericin B with appropriate physicochemical properties and antifungal activity. PLGA was functionalized with GalN to increase the adhesion and antifungal activity of NPs against Candida albicans.

Methods: The physicochemical properties of NPs were characterized by particle size determination, zeta potential, drug crystallinity, loading efficiency, dissolution studies, differential scanning calorimeter (DSC), X-ray powder diffraction (XRPD), and Fourier transform infrared (FT-IR). Antifungal activity of the NPs at different drug/polymer ratios was examined by determining minimum inhibitory concentrations (MICs).

Results: the FT-IR and ¹ HNMR analysis successfully confirmed the formation of PLGA- PEG-GalN NPs. The PLGA NPs were in the size range of 174.1 ± 3.49 to 238.2±7.59 nm while PLGA-GalN NPs were 255.6 ±4.08 nm in size , respectively. Loading efficiency was in the range of 67%±2.4 to 77%±1.6, and entrapment efficiency in the range of 68.185%±1.9 to 73.05%±0.6. Zeta potential and loading efficiency for PLGA-GalN NPs were –0.456, 71%. The NPs indicated an amorphous status according to XRPD patterns and DSC thermograms. The PLGA-PEG-GalN NPs showed higher fungistatic activity than PLGA NPs.

Conclusion: the results demonstrated that the antifungal activity of PLGA-PEG-GalN NPs was higher than pure amphotericin B and PLGA NPs.

Galactosamine reduces sandfly gut protease activity through TOR downregulation and increases Lutzomyia susceptibility to Leishmania

In sandflies, males and females feed on carbohydrates but females must get a blood meal for egg maturation. Using artificial blood meals, this study aimed to understand how galactosamine interferes with sandfly digestive physiology. We also used galactosamine to manipulate the digestive physiology of Lutzomyia longipalpis to investigate its influence on sandfly digestion and Leishmania development within their insect vectors. Galactosamine was capable to reduce Lu. longipalpis trypsinolytic activity in a dose-dependent manner. This effect was specific to galactosamine as other similar sugars were not able to affect sandfly trypsin production. An excess of amino acids supplemented with the blood meal and 15 mM galactosamine was able to abrogate the reduction of the trypsinolytic activity caused by galactosamine, suggesting this phenomenon may be related to an impairment of amino acid detection by sandfly enterocytes. The TOR inhibitor rapamycin reduces trypsin activity in the L. longipalpis midgut. Galactosamine reduces the phosphorylation of the TOR pathway repressor 4EBP, downregulating TOR activity in the gut of L. longipalpis. Galactosamine reduces sandfly oviposition, causes an impact on sandfly longevity and specifically reduces sandfly gut proteases whereas increasing α-glycosidase activity. The administration of 15 and 30 mM galactosamine increased the number of promastigote forms of Le. mexicana and Le. infantum in galactosamine-treated L. longipalpis. Our results showed that galactosamine influences amino acid sensing, reduces sandfly gut protease activity through TOR downregulation, and benefits Leishmania growth within the Lu. longipalpis gut.

Correlation between synthesis of α2-macroglobulin as acute phase protein and degree of hepatopathy in rats

The degree of hepatopathy affecting the synthesis of α₂-macroglobulin (α2M) as an acute phase protein in rats was investigated. Hepatopathy was induced in Sprague-Dawley rats by intravenous administration of galactosamine at a dose of 30 mg/kg for 7 days. Inflammation was induced by intramuscular injection of turpentine oil at a dose of 2 mL/kg. Blood was collected before turpentine oil injection and at 24, 48, 72 and 96 h after injection. Serum concentrations of α2M were measured by enzyme-linked immunosorbent assay. Mean values of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in rats administered galactosamine were significantly higher than in controls. Mean values of body weight and total protein were significantly lower than in controls. Serum concentrations of α2M in the galactosamine group were significantly lower than in controls. Kinetic parameters, area under the concentration-time curve (AUC^0-96) and maximum serum concentration (Cmax), were significantly lower than in controls. The cut-off value for detecting the effects on synthesis of α2M in liver was 46.9 mgˑh/mL. Seven rats (77.8%) were assessed for decreases in the synthesis of α2M due to hepatopathy. Two rats showed no influence on the synthesis of α2M, despite administration of galactosamine. AST and ALT in these two rats were ≤ 285 and ≤ 174 U/L, respectively. In conclusion, synthesis of α2M in rats is evidently suppressed in the severe stages of hepatopathy.

Assessment of animal experimental models of toxic liver injury in the context of their potential application as preclinical models for cell therapy

Preclinical animal models allow to study development and progression of several diseases, including liver disorders. These studies, for ethical reasons and medical limits, are impossible to carry out in human patients. At the same time, such experimental models constitute an important source of knowledge on pathomechanisms for drug- and virus-induced hepatotoxicity, both acute and chronic. Carbon tetrachloride, D-Galactosamine, and retrorsine are xenobiotics that can be used in immunocompetent animal models of hepatotoxicity, where chemical-intoxicated livers present histological features representative of human viruses-related infection. A prolonged derangement into liver architecture and functions commonly lead to cirrhosis, eventually resulting in hepatocellular carcinoma. In human, orthotopic liver transplantation commonly resolve most the problems related to cirrhosis. However, the shortage of donors does not allow all the patients in the waiting list to receive an organ on time. A promising alternative treatment for acute and chronic liver disease has been advised in liver cell transplantation, but the limited availability of hepatocytes for clinical approaches, in addition to the immunosuppressant regiment required to sustain cellular long-term engraftment have been encouraging the use of alternative cell sources. A recent effective source of stem cells have been recently identified in the human amnion membrane. Human amnion epithelial cells (hAEC) have been preclinically tested and proven sufficient to rescue immunocompetent rodents lethally intoxicated with drugs. The adoption of therapeutic procedures based on hAEC transplant in immunocompetent recipients affected by liver diseases, as well as patients with immune-related disorders, may constitute a successful new alternative therapy in regenerative medicine.

Taurine Enhances the Protective Actions of Fish Oil Against D-Galactosamine-Induced Metabolic Changes and Hepatic Lipid Accumulation and Injury in the Rat

This study has evaluated the effects of a supplementation with taurine (TAU) on the actions of fish oil (FO) against the hypoglycemia, hypoproteinemia, and hepatic accumulation of lipids and liver damage caused by D-galactosamine (GAL) in the rat. To this end, male Sprague-Dawley rats (200-225 g), in groups of 6, were orally treated with physiological saline (2.5 mL, control group), FO (60 mg/kg), TAU (2.4 mmol/kg) or FO-TAU for three consecutive days and before a single oral dose of GAL (400 mg/kg) given on day 3. In parallel, rats receiving only GAL on day 3 or N-acetylcysteine (NAC, 2.4 mmol/kg) for 3 days before GAL served as controls. On day 4 blood samples were collected by cardiac puncture and used to either measure glucose (GLC) or to obtain plasma fractions. Immediately thereafter, the livers were excised, made into a homogenate in phosphate buffered saline pH 7.4, and centrifuged to obtain clear supernatant. Plasma samples were assayed for their total protein (TP), triglycerides (TG), cholesterol (CHOL), phospholipids (PLP), free fatty acids (FFA) and total bilirubin (TB) and direct bilirubin (DB) contents, and for the activities of alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP). The liver homogenates were used to measure TG, CHOL, PLP and total lipids (TL) contents. Without exceptions, GAL was found to markedly affect (p < 0.001) all of the experimental parameters examined, with increases occurring in all instances except for the values of the plasma GLC, TP and PLP which were decreased. A pretreatment with either FO or TAU led to significant attenuation of the effects of GAL and which, in most cases, were of similar magnitude. On the other hand, a combined pretreatment with FO plus TAU usually resulted in a greater protection than with either agent alone (p ≤ 0.05). NAC, serving as a reference treatment, was, in most instances, equipotent with FO alone and. in addition, was the only agent that significantly attenuated the increases in both liver weight and liver weight to body weight ratio caused by GAL.

Protective Effects of the Third Generation Vasodilatory Βeta - Blocker Nebivolol against D-Galactosamine - Induced Hepatorenal Syndrome in Rats

BACKGROUND:

Renal dysfunction is very common in patients with advanced liver cirrhosis and portal hypertension. The development of renal failure in the absence of clinical, anatomical or pathological causes renal of failure is termed hepatorenal syndrome (HRS).

AIM:

The present study was constructed to investigate the possible protective effects of nebivolol (Nebi) against D-galactosamine (Gal)-induced HRS in rats.

MATERIAL AND METHODS:

Rats were treated with Nebi for ten successive days. On the 8th day of the experiment, they received a single dose of Gal. Serum levels of Cr, BUN, Na+ and K+ as well as AST, ALT, total bilirubin (TB), NH3 and endothelin-1 (ET-1) were determined following Gal administration. Moreover, renal and liver contents of MDA, GSH, F2-isoprostanes (F2-IPs), tumor necrosis factor-alpha (TNF-α), nuclear factor kappa-B (NF-κB), total nitric oxide (NO), in addition to activities of caspase-3 (Cas-3), heme oxygenase-1 (HO-1), inducible and endothelial NO synthase (iNOS and eNOS) enzymes were also assessed. Finally, histopathological examination was performed.

RESULTS:

Nebi attenuated Gal-induced renal and hepatic dysfunction. It also decreased the Gal-induced oxidative stress and inflammatory recruitment.

CONCLUSION:

Results demonstrated both nephroprotective and hepatoprotective effects of Nebi against HRS and suggested a role of its antioxidant, anti-inflammatory, anti-apoptotic and NO-releasing properties.

Macrophage autophagy limits acute toxic liver injury in mice through down regulation of interleukin-1β

BACKGROUND & AIMS

Overactivation of the innate immune response underlies many forms of liver injury including that caused by hepatotoxins. Recent studies have demonstrated that macrophage autophagy regulates innate immunity and resultant tissue inflammation. Although hepatocyte autophagy has been shown to modulate hepatic injury, little is known about the role of autophagy in hepatic macrophages during the inflammatory response to acute toxic liver injury. Our aim therefore was to determine whether macrophage autophagy functions to down regulate hepatic inflammation.

METHODS

Mice with a LysM-CRE-mediated macrophage knockout of the autophagy gene ATG5 were examined for their response to toxin-induced liver injury from D-galactosamine/lipopolysaccharide (GalN/LPS).

RESULTS

Knockout mice had increased liver injury from GalN/LPS as determined by significant increases in serum alanine aminotransferase, histological evidence of liver injury, positive terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate nick end-labeling, caspase activation and mortality as compared to littermate controls. Levels of proinflammatory tumor necrosis factor and interleukin (IL)-6 hepatic mRNA and serum protein were unchanged, but serum IL-1β was significantly increased in knockout mice. The increase in serum IL-1β was secondary to elevated hepatic caspase 1 activation and inflammasome-mediated cleavage of pro-IL-1β to its active form. Cultured hepatic macrophages from GalN/LPS-treated knockout mice had similarly increased IL-1β production. Dysregulation of IL-1β was the mechanism of increased liver injury as an IL-1 receptor antagonist prevented injury in knockout mice in concert with decreased neutrophil activation.

CONCLUSIONS

Macrophage autophagy functions to limit acute toxin-induced liver injury and death by inhibiting the generation of inflammasome-dependent IL-1β.

Broccoli sprout extract induces detoxification-related gene expression and attenuates acute liver injury

AIM: To investigate the effects of broccoli sprout extract (BSEx) on liver gene expression and acute liver injury in the rat.

METHODS: First, the effects of BSEx on liver gene expression were examined. Male rats were divided into two groups. The Control group was fed the AIN-76 diet, and the BSEx group was fed the AIN-76 diet containing BSEx. After a 10-d feeding period, rats were sacrificed and their livers were used for DNA microarray and real-time reverse transcription-polymerase chain reaction (RT-PCR) analyses. Next, the effects of BSEx on acute liver injury were examined. In experiments using acute liver injury models, 1000 mg/kg acetaminophen (APAP) or 350 mg/kg D-galactosamine (D-GalN) was used to induce injury. These male rats were divided into four groups: Control, BSEx, Inducer (APAP or D-GalN), and Inducer+BSEx. The feeding regimens were identical for the two analyses. Twenty-four hours following APAP administration via p.o. or D-GalN administration via i.p., rats were sacrificed to determine serum aspartate transaminase (AST) and alanine transaminase (ALT) levels, hepatic glutathione (GSH) and thiobarbituric acid-reactive substances accumulation and glutathione-S-transferase (GST) activity.

RESULTS: Microarray and real-time RT-PCR analyses revealed that BSEx upregulated the expression of genes related to detoxification and glutathione synthesis in normal rat liver. The levels of AST (70.91 ± 15.74 IU/mL vs 5614.41 ± 1997.83 IU/mL, P < 0.05) and ALT (11.78 ± 2.08 IU/mL vs 1297.71 ± 447.33 IU/mL, P < 0.05) were significantly suppressed in the APAP + BSEx group compared with the APAP group. The level of GSH (2.61 ± 0.75 nmol/g tissue vs 1.66 ± 0.59 nmol/g tissue, P < 0.05) and liver GST activity (93.19 ± 16.55 U/g tissue vs 51.90 ± 16.85 U/g tissue, P < 0.05) were significantly increased in the APAP + BSEx group compared with the APAP group. AST (4820.05 ± 3094.93 IU/mL vs 12465.63 ± 3223.97 IU/mL, P < 0.05) and ALT (1808.95 ± 1014.04 IU/mL vs 3936.46 ± 777.52 IU/mL, P < 0.05) levels were significantly suppressed in the D-GalN + BSEx group compared with the D-GalN group, but the levels of AST and ALT in the D-GalN + BSEx group were higher than those in the APAP + BSEx group. The level of GST activity was significantly increased in the D-GalN + BSEx group compared with the D-GalN group (98.04 ± 15.75 U/g tissue vs 53.15 ± 8.14 U/g tissue, P < 0.05).

CONCLUSION: We demonstrated that BSEx protected the liver from various types of xenobiotic substances through induction of detoxification enzymes and glutathione synthesis.

Lycopene stabilizes lipoprotein levels during D-galactosamine/lipopolysaccharide induced hepatitis in experimental rats

OBJECTIVE

To investigate the effect of lycopene on lipoprotein metabolism during D-galactosamine/lipopolysaccharide (D-Gal/LPS) induced hepatitis in experimental rats.

METHODS

The efficacy of lycopene was validated during D-Gal/LPS induced hepatitis by analyzing the activity of lipid metabolizing enzymes such as lipoprotein lipase (LPL), lecithin-cholesterol acyl transferase (LCAT) and hepatic triglyceride lipase (HTGL). Lipo protein analyses were done by the estimation of very low density lipoprotein cholesterol (VLDL), low density lipoprotein cholesterol (LDL) and high density lipoprotein cholesterol (HDL).

RESULTS

The toxic insult of D-galactosamine/lipopolysaccharide (D-Gal/LPS) in experimental group of animals reduces the normal values of lipid metabolizing enzymes due to liver injury. The significant drop in the levels of HDL and concomitant increase in the values of VLDL and LDL were observed. The pretreatment of lycopene restore these altered values to near normal level in experimental group of animals.

CONCLUSIONS

In the light of results, it can be concluded that administration lycopene stabilizes the lipoprotein levels by regulating the lipid metabolizing enzymes through its antioxidant defense and helps to maintain the normal lipid metabolism during toxic injury in liver.

The presence of a galactosamine substituent on the arabinogalactan of Mycobacterium tuberculosis abrogates full maturation of human peripheral blood monocyte-derived dendritic cells and increases secretion of IL-10

Slow-growing and pathogenic Mycobacterium spp. are characterized by the presence of galactosamine (GalN) that modifies the interior branched arabinosyl residues of the arabinogalactan (AG) that is a major heteropolysaccharide cell wall component. The availability of null mutants of the polyprenyl-phospho-N-acetylgalactosaminyl synthase (Rv3631, PpgS) and the (N-acetyl-) galactosaminyl transferase (Rv3779) of Mycobacterium tuberculosis (Mtb) has provided a means to elucidate the role of the GalN substituent of AG in terms of host-pathogen interactions. Comparisons of treating human peripheral blood monocyte-derived dendritic cells (hPMC-DCs) with wild-type, Rv3631 and Rv3779 mutant strains of Mtb revealed increased expression of DC maturation markers, decreased affinity for a soluble DC-SIGN probe, reduced IL-10 secretion and increased TLR-2-mediated NF-κB activation among GalN-deficient Mtb strains compared to GalN-producing strains. Analysis of surface expression of a panel of defined or putative DC-SIGN ligands on both WT strains or either Rv3631 or Rv3779 mutant did not show significant differences suggesting that the role of the GalN substituent of AG may be to modulate access of the bacilli to immunologically-relevant receptor domains on DCs or contribute to higher ordered pathogen associated molecular pattern (PAMP)/pattern recognition receptor (PRR) interactions rather than the GalN-AG components having a direct immunological effect per se.

Hepatoprotective effect of nitric oxide in experimental model of acute hepatic failure

AIM: To evaluate the effect of nitric oxide (NO) on the development and degree of liver failure in an animal model of acute hepatic failure (AHF).

METHODS: An experimental rat model of galactosamine-induced AHF was used. An inhibitor of NO synthase, nitroarginine methyl ester, or an NO donor, arginine, were administered at various doses prior to or after the induction of AHF.

RESULTS: All tested groups developed AHF. Following inhibition of the endogenous NO pathway, most liver parameters improved, regardless of the inhibitor dose before the induction of liver damage, and depending on the inhibitor dose after liver damage. Prophylactic administration of the inhibitor was more effective in improving liver function parameters than administration of the inhibitor after liver damage. An attempt to activate the endogenous NO pathway prior to the induction of liver damage did not change the observed liver function parameters. Stimulation of the endogenous NO pathway after liver damage, regardless of the NO donor dose used, improved most liver function parameters.

CONCLUSION: The endogenous NO pathway plays an important role in the development of experimental galactosamine-induced AHF.

Determination of galactosamine impurities in heparin sodium using fluorescent labeling and conventional high-performance liquid chromatography

Heparin is a sulfated glycosaminoglycan (GAG), which contains N-acetylated or N-sulfated glucosamine (GlcN). Heparin, which is generally obtained from the healthy porcine intestines, is widely used as an anticoagulant during dialysis and treatments of thrombosis such as disseminated intravascular coagulation. Dermatan sulfate (DS) and chondroitin sulfate (CS), which are galactosamine (GalN)-containing GAGs, are major process-related impurities of heparin products. The varying DS and CS contents between heparin products can be responsible for the different anticoagulant activities of heparin. Therefore, a test to determine the concentrations of GalN-containing GAG is essential to ensure the quality and safety of heparin products. In this study, we developed a method for determination of relative content of GalN from GalN-containing GAG in heparin active pharmaceutical ingredients (APIs). The method validation and collaborative study with heparin manufacturers and suppliers showed that our method has enough specificity, sensitivity, linearity, repeatability, reproducibility, and recovery as the limiting test for GalN from GalN-containing GAGs. We believe that our method will be useful for ensuring quality, efficacy, and safety of pharmaceutical heparins. On July 30, 2010, the GalN limiting test based on our method was adopted in the heparin sodium monograph in the Japanese Pharmacopoeia.

Comparison of protective effects of compound ammonium glycyrrhetate and magnesium isoglycyrrhizinate on D-galactosamine- and carbon tetrachloride-injured human hepatocytes

AIM: To compare the protective effects of compound ammonium glycyrrhetate (CAG) and magnesium isoglycyrrhizinate (MI) on D-galactosamine (D-GalN)- and carbon tetrachloride (CCl₄)-injured human hepatocytes (L-02).

METHODS: After L-02 cells were treated with CAG and MI, respectively, they were incubated with CCl4 or D-GalN to induce cell injury. Cell growth was observed under an inverted microscope. The activity of aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) and the content of glutathione (GSH) in culture supernatants were determined.

RESULTS: At a concentration of 1 g/L, both CAG and MI could improve the survival rate of cells, significantly inhibit D-GalN- and CCl₄-induced release of AST and LDH and intracellular GSH depletion, and increase D-GalN- and CCl₄-induced decrease in mitochondrial membrane potential. Both of the CAG and MI can inhibit D-GalN and CCl₄-induced release of AST and LDH and intracellular GSH depletion (CCl₄: 7.59 ± 1.27, 5.23 ± 0.70 vs 3.33 ± 0.40; D-GalN: 7.93 ± 0.36, 5.40 ± 0.52vs 3.77 ± 0.45, P < 0.01 or 0.05).

CONCLUSION: At a concentration of 1 g/L, both CAG and MI can exert protective effects on D-GalN and CCl4-injured human hepatocytes perhaps via a mechanism that is associated with improving intracellular GSH depletion. CAG is superior to MI in protecting injured L-02 hepatocytes.