S.-J. Hong

Biotransformation of glycyrrhizin by human intestinal bacteria and its relation to biological activities.

The relationship between the metabolites of glycyrrhizin (18β-glycyrrhetinic acid-3-O-β-d-glucuronopyranosyl-(1→2)-β-d-glucuronide, GL) and their biological activities was investigated. By human intestinal microflora, GL was metabolized to 18β-glycyrrhetinic acid (GA) as a main product and to 18β-glycyrrhetinic acid-3-O-β-d-glucuronide (GAMG) as a minor product. The former reaction was catalyzed byEubacterium L-8 and the latter was byStreptococcus LJ-22. Among GL and its metabolites, GA and GAMG had more potentin vitro anti-platelet aggregation activity than GL. GA also showed the most potent cytotoxicity against tumor cell lines and the potent inhibitory activity on rotavirus infection as well as growth ofHelicobacter pylori. GAMG, the minor metabolite of GL, was the sweetest.

Metabolic Activities of Ginseng and Its Constituents, Ginsenoside Rb 1 and Rg 1 , by Human Intestinal Microflora

To evaluate the difference in expressing pharmacological effects of ginseng by intestinal microflora between Koreans, metabolic activities of ginseng, ginsenoside Rb1 and Rg1 by 100 fecal specimens were measured. The β-glucosidase activity for p-nitrophenyl- β-D-glucopyranoside was 0 to 0.42 μmol/min/mg and its average activity (mean±SD) was 0.10±0.07 μmol/min/mg. The metabolic activities of ginsenosides Rb1 and Rg1 were 0.01 to 0.42 and 0.01 to 0.38 pmol/min/mg, respectively. Their average activities were 0.25±0.08 and 0.15±0.09 pmol/min/mg, respectively. The compound K-forming activities from ginsenoside Rb1 and ginseng extract were 0 to 0.11 and 0 to 0.02 pmol/min/mg, respectively. Their average compound K-forming activities were 0.24±0.09 pmol/min/ mg and 2.14±3.66 fmol/min/mg, respectively. These activities all were not different between males and females, or between ages. Although compound K-forming activity from the aqueous extract of ginseng was low compared to that from ginenoside Rb1, their profiles were similar to those of isolated compounds. Based on these findings, we believe that the intestinal bacterial metabolic activities of ginseng components are variable in individuals and may be used as selection markers for responders to ginseng.

Topiramate stimulates glucose transport through AMP-activated protein kinase-mediated pathway in L6 skeletal muscle cells

The use of topiramate (TPM) in the treatment of binge-eating disorder, bulimia nervosa, and antipsychotic-induced weight gain has recently increased, however, the exact molecular basis for its effects on body weight reduction and improved glucose homeostasis, is yet to be elucidated. Here we investigated the effect and signaling pathway of TPM on glucose uptake in L6 rat skeletal muscle cells, which account for >70% of glucose disposal in the body. Intriguingly, we found that TPM (10 μM) stimulated the rate of glucose uptake up to twofold increase. And TPM-stimulated glucose transport was inhibited with the overexpression of dominant-negative form of AMP-activated protein kinase (AMPK), an important mediator in glucose transport, implicating that AMPK-mediated pathway is involved. The TPM-stimulated glucose transport was blocked by SB203580, a specific inhibitor of AMPK downstream mediator, p38 mitogen-activated protein kinase (MAPK) protein. LY294002, an inhibitor of phosphatidylinositol (PI) 3-kinase, which is another crucial mediator in independent glucose transport pathway, did not inhibit TPM-stimulated glucose transport. We also found that TPM increased the phosphorylation level of AMPK and p38 MAPK, whereas no effect on the activity of PI 3-kinase of TPM, when assessed by PI 3-kinase assay, was observed. These results together suggest that TPM stimulates glucose transport, not via PI 3-kinase mediated, but via AMPK-mediated pathway in skeletal muscle cells, thereby contributing to the body weight regulation and glucose homeostasis.

Soyasaponins Ab and Bb Prevent Scopolamine-Induced Memory Impairment in Mice without the Inhibition of Acetylcholinesterase

Soy (Glycine max, family Leguminosae), which contains isoflavones and saponins as main constituents, is known to exhibit memory-enhancing effects. Therefore, to investigate the role of soyasaponins in memory impairments, we isolated soyasaponins Ab (SA) and Bb (SB) from soybean and measured their protective effects against scopolamine-induced memory impairment in mice. SA and SB significantly prevented scopolamine-induced memory impairment in passive avoidance and Y-maze tasks. Compared to SA, SB rescued memory impairment more potently. Treatment with SB (10 mg/kg, p.o.) protected memory impairment in passive avoidance and Y-maze tasks to 97% (F = 68.10, P < 0.05) and 78% (F = 35.57, P < 0.05) of untreated normal control level, respectively. SA and SB (10 mg/kg) also rescued scopolamine-induced memory impairment in Morris water maze task (F = 14.51, P < 0.05). In addition, soyasaponins preserved brain-derived neurotrophic factor (BNDF) expression (F = 33.69, P < 0.05) and cAMP response element-binding (CREB) protein phosphorylation (F = 91.62, P < 0.05) in the hippocampus of scopolamine-treated mice. However, SA and SB did not inhibit acetylcholinesterase in vitro and ex vivo. On the basis of these findings, we suggest that soybean, particularly soyasaponins, may protect memory impairment by increasing BDNF expression and CREB phosphorylation.

Gypenoside TN-2 ameliorates scopolamine-induced learning deficit in mice.

ETHNOPHARMACOLOGICAL RELEVANCE Gynostemma pentaphyllum (Thunb.) Makino (GP, family Cucurbitaceae), which contains dammarane saponins as its main constituents, is used in China, Japan, and Korea as a traditional medicine to treat cancer, obesity, arteriosclerosis, asthma and senility. AIM OF THE STUDY To investigate the memory-enhancing effects of GP, Gypenoside TN-2 (TN-2) was isolated by activity-guided fractionation and administered to scopolamine-induced memory-deficient mice. MATERIALS AND METHODS The memory-enhancing effects of TN-2 were evaluated using passive avoidance, Y-maze, and Morris water maze tests, and the protein expressions of brain-derived neurotrophic factor (BDNF), cAMP element binding protein (CREB), and p-CREB were determined by immunoblotting. RESULTS TN-2 inhibited memory and learning deficits in scopolamine treated mice in the passive avoidance test. TN-2 (10, 20, and 40 mg/kg, p.o.) significantly inhibited memory and learning deficits in the passive avoidance test by 40%, 96% and 78%, respectively, and exhibited significant memory-enhancing effects on the Y-maze test and the Morris water maze test. TN-2 also markedly increased BNDF expression and activated the transcription factor CREB in the hippocampi of scopolamine-treated mice. CONCLUSIONS TN-2 may ameliorate memory and learning deficits by activating the CREB-BDNF pathway.

The interleukin-1 family gene polymorphisms in Korean patients with rheumatoid arthritis

Objective: The interleukin (IL)-1 family and its related family members are primary inflammatory cytokines. The aim of this study was to assess the possible association between nine IL-1 family gene polymorphisms and rheumatoid arthritis (RA). Methods: To investigate the genetic association between IL-1 family gene polymorphisms and the risk of RA in a Korean population, 69 single nucleotide polymorphisms (SNPs) of the nine IL-1 family gene regions were selected. A total of 806 subjects (498 controls and 308 RA patients) were included in the study. The genotypes of the selected SNPs in the IL-1 family genes were determined using Illumina Sentrix Array Matrix chips. SNP Stats, Haploview, and SNP Analyzer, and Helixtree programs were used for the analysis of the genetic data. Results: We observed statistically significant associations between the SNPs of IL1F10 and IL1RN among the IL-1 family genes in the RA patients and the control population. When the patients were divided into two groups according to the parameters of disease activity, including C-reactive protein (CRP) level (≥ 0.5 or < 0.5 mg/dL), the erythrocyte sedimentation rate (ESR) (≥ 30 or < 30 mm/h), and parameters of severity, including rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP), and bone erosion (positive or not), we found significant associations between the parameters, including CRP, ESR, and bone erosion, and SNPs of the IL-1 family genes in RA. Conclusion: This study suggests that IL-1 family gene (IL1F10 and IL1RN) polymorphisms may play an important role in the susceptibility to developing RA.

Magnolia officinalis attenuates free fatty acid-induced lipogenesis via AMPK phosphorylation in hepatocytes

ETHNOPHARMACOLOGICAL RELEVANCE Magnolia officinalis (MO) is a traditional Chinese herbal medicine that has been used in clinical practice to treat liver disease. The aim of this study is to examine the effects of MO on the development of nonalcoholic fatty liver in hepatocytes. MATERIALS AND METHODS Human hepatoma-derived HepG2 cells and mouse normal FL83B hepatocytes were exposed to 0.5mM free fatty acids (FFAs; oleate:palmitate, 2:1) for 24h to simulate conditions of nonalcoholic fatty liver in vitro. The cells were treated with a standardized MO extract 1h prior to FFA exposure. RESULTS MO pretreatment attenuated the increases in intracellular lipid accumulation and triglyceride content in FFA-exposed hepatocytes in a dose-dependent manner. MO pretreatment significantly inhibited both sterol regulatory element-binding protein (SREBP)-1c activation and increases in fatty acid translocase, fatty acid synthase, and stearoyl CoA desaturase-1 protein expression in FFA-exposed hepatocytes in a dose-dependent manner. MO pretreatment markedly induced adenosine monophosphate-activated protein kinase (AMPK) phosphorylation in hepatocytes. Compound C, an AMPK inhibitor, blocked the inhibitory effect of MO on the increases in intracellular lipid accumulation and triglyceride content induced by FFAs. In hepatocytes pretreated with compound C, MO failed to inhibit SREBP-1c activation and the increases in fatty acid translocase, fatty acid synthase, and stearoyl-CoA desaturase-1 protein expression induced by FFAs. CONCLUSIONS Our results indicate that MO attenuates triglyceride biosynthesis and accumulation induced by FFAs in hepatocytes, suggesting its pharmacological potential for the prevention of nonalcoholic fatty liver disease. These effects may be mediated by the inhibition of SREBP-1c via AMPK phosphorylation.

Association of the -2510A/G chemokine (C-C motif) ligand 2 polymorphism with knee osteoarthritis in a Korean population.

Objective: To investigate the possible association between polymorphisms [the −2510A/G promoter polymorphism (rs1024611) and the Cys35Cys coding polymorphism (rs4586) in exon 2] of the chemokine (C–C motif) ligand 2 (CCL2) gene and knee osteoarthritis (OA) in a Korean population. Methods: DNA was obtained from 153 Korean primary knee OA patients and 270 healthy controls. CCL2 genomic variants (−2510A/G and Cys35Cys polymorphisms) were detected by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). In additional, the effect of −2510A/G on CCL2 transcription was examined, using a luciferase reporter gene construct transfected into HMC‐1 cells. Results: The −2510A/G promoter polymorphism was associated with OA [genotype frequency, p = 0.041; allele frequency, p = 0.017, odds ratio (OR) = 1.45, 95% confidence interval (CI) = 1.07–1.96]. Significant association was observed between the G carrier of the −2510A/G promoter polymorphism and primary knee OA patients (p = 0.021, OR = 2.25, 95% CI = 1.12–4.52). The G carrier of the −2510A/G promoter polymorphism was also associated with both clinically subtyped OA patients (OA patients with functionally poor index and radiographically severe OA patients). However, no significant difference was found in the Cys35Cys polymorphism. Haplotype frequency analysis revealed a significant difference (χ2 = 8.98, p = 0.030). The CCL2 serum level of subjects with the G carrier (290.0±87.5 pg/mL) of the −2510A/G promoter polymorphism was statistically higher than that of subjects with the non‐G carrier (161.5±48.3 pg/mL). The luciferase activity was significantly greater from interleukin (IL)‐1β‐induced cells transfected with constructs containing G at position −2510. Conclusions: The G carrier of the −2510A/G promoter polymorphism was found to be associated with primary knee OA, and could be a susceptibility factor in the development of primary knee OA in the Korean population.

HS-23, Lonicera japonica extract, attenuates septic injury by suppressing toll-like receptor 4 signaling.

ETHNOPHARMACOLOGICAL RELEVANCE Lonicera japonica Thunberg is a traditional herbal medicine widely used in East Asia as an anti-bacterial, anti-inflammatory, and antiviral agent. This study was designed to investigate the effects of HS-23, ethanol extract of the dried flower buds of Lonicera japonica, in experimental models of sepsis and elucidate the mechanisms of action of HS-23. MATERIALS AND METHODS Male ICR mice were intravenously administered HS-23 (20 and 40 mg/kg) for 0 (immediately) and 24 h after cecal ligation and puncture (CLP) for survival tests, and HS-23 (40 mg/kg) immediately after CLP for biochemical assays. RESULTS HS-23 improved sepsis-induced mortality, enhanced bacterial clearance, and attenuated multiple organ failure. The mechanisms of action of HS-23 included attenuation of increased toll-like receptor (TLR)4 protein and mRNA expression. HS-23 suppressed sepsis-induced increases in protein expression of myeloid differentiation primary response protein 88, p38 and c-Jun N-terminal kinase in both liver and lung, as well as TIR-domain-containing adapter-inducing interferon-β and interferon regulatory transcription factor 3 protein expression in liver. CONCLUSION The results of this study revealed that HS-23 attenuated sepsis through suppression of TLR signaling pathways. Therefore, our findings suggest that HS-23 might be useful as a potential therapeutic agent for treatment of sepsis.

Identifying fibromyalgia subgroups using cluster analysis: Relationships with clinical variables

Patients with fibromyalgia (FM) exhibit significant clinical heterogeneity, in terms of physical, social and psychological functions, as well as therapeutic responses. Here, we examined FM patients in terms of pain, physical, social and psychological variables to identify clinical subgroups that may be predictive of treatment patterns.