Seok-Jong Suh

Tanshinone IIA from Salvia miltiorrhiza BUNGE inhibits human aortic smooth muscle cell migration and MMP-9 activity through AKT signaling pathway.

Smooth muscle cell (SMC) migration plays an important role in normal angiogenesis and is relevant to disease‐related vascular remodeling in conditions such as brain arteriovenous malformations, pulmonary hypertension, arteriosclerosis, and restenosis after angioplasty. In this present study, we showed that tanshinone IIA, the major lipid‐soluble pharmacological constituent of Salvia miltiorrhiza BUNGE, inhibits human aortic smooth muscle cell (HASMC) migration and MMP‐9 activity. Tanshinone IIA significantly inhibited IκBα phosphorylation and p65 nuclear translocation through inhibition of AKT phosphorylation. Tanshinone IIA inhibited TNF‐α‐induced ERK and c‐jun phosphorylation, but not other MAPKs such as JNK and p38. Tanshinone IIA also inhibited NF‐κB and AP‐1 DNA‐binding. Moreover, tanshinone IIA inhibited the migration of TNF‐α‐induced HASMCs. Our results provide evidence that tanshinone IIA has multiple effects in the inhibition of HASMC migration and may offer a therapeutic approach to block HASMC migration. J. Cell. Biochem. 104: 15–26, 2008.

Anti-inflammatory activity of bark of Dioscorea batatas DECNE through the inhibition of iNOS and COX-2 expressions in RAW264.7 cells via NF-κB and ERK1/2 inactivation.

We identified a bioactive herbal medicine with anti-inflammatory activity from an ethanol extract derived from the bark of Dioscorea batatas DECNE (BDB) in RAW264.7 cells. We examined the effects of BDB on nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production in LPS-induced RAW264.7 cells. BDB consistently inhibited both NO and PGE(2) production in a dose-dependent manner, with an IC(50) of 87-71 μg/ml, respectively. The reduction of NO and PGE(2) production were accompanied by a reduction in iNOS and COX-2 protein expression, as evaluated by Western blotting. To evaluate the action mode of BDB and its ability to inhibit iNOS and COX-2 protein expression, we assessed the effects of BDB on nuclear factor-κB (NF-κB) DNA-binding activity, NF-κB-dependent reporter gene activity, inhibitory factor-κB (IκB) phosphorylation and degradation, and p65 nuclear translocation. BDB suppressed DNA-binding activity and reporter gene activity as well as translocation of the NF-κB p65 subunit. BDB also down-regulated IκB kinase (IKK), thus inhibiting LPS-induced both phosphorylation and the degradation of IκBα. In addition, BDB also inhibited the LPS-induced activation of ERK1/2.

Propolis induces cell cycle arrest and apoptosis in human leukemic U937 cells through Bcl-2/Bax regulation

We investigated mechanism(s) where propolis induces apoptosis in human leukemic U937 cells. Propolis inhibited the proliferation of U937 cells in a dose-dependent manner by inducing apoptosis and blocking cell cycle progression in the G2/M phase. Western blot analysis showed that propolis increases the expression of p21 and p27 proteins, and decreases the levels of cyclin B1, cyclin A, Cdk2 and Cdc2, thereby contributing to cell cycle arrest. DAPI staining assay revealed typical morphology features of apoptotic cells. Propolis-induced apoptosis was also confirmed by assays with annexin V-FITC, PI-labeling and DNA fragmentation assay. The increase in apoptosis level induced by propolis was associated with down-regulation of Bcl-2 and activation of caspase-3, but not with Bax. These results suggests that propolis-induced apoptosis is related to the selective activation of caspase-3 and induction of Bcl-2/Bax regulation.

Saucerneol F, a new lignan, inhibits iNOS expression via MAPKs, NF-κB and AP-1 inactivation in LPS-induced RAW264.7 cells.

Saucerneol F (SF), a new tetrahydrofuran-type sesquilignan isolated from Saururus chinensis, dose-dependently inhibited nitric oxide (NO) production, with concomitant reduction of inducible nitric oxide synthase (iNOS) protein and mRNA expression in lipopolysaccharide (LPS)-stimulated murine macrophage RAW264.7 cells. To elucidate the molecular mechanism underlying the inhibition of iNOS expression by SF, we assessed the effects of SF on nuclear factor-κB (NF-κB) DNA-binding activity, NF-κB-dependent reporter gene activity, inhibitory factor-κB (IκB) phosphorylation and degradation, and p65 nuclear translocation. Treatment with SF decreased the luciferase activities of NF-κB reporter promoters in a dose-dependent manner and translocation of NF-κB p65. In addition, pretreatment of SF reduced LPS-stimulated activation of mitogen-activated protein kinases (MAPKs) including extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAPK, and c-Jun NH(2)-terminal kinase (JNK). Furthermore, SF attenuated the luciferase activities of AP-1 reporter promoters and the DNA-binding capacity of AP-1. Taken together, the present results indicate that SF attenuates NO production and iNOS expression by blocking LPS-induced activation of NF-κB, MAPKs, and AP-1, suggesting that SF is potentially applicable as an anti-inflammatory drug.

Deoxypodophyllotoxin, flavolignan, from Anthriscus sylvestris Hoffm. inhibits migration and MMP-9 via MAPK pathways in TNF-α-induced HASMC.

The matrix metalloproteinases (MMP-9 and MMP-2) in aortic smooth muscle cells (SMC) play key roles in the pathogenesis atherosclerosis. The SMC migration into the vascular wall via the bloodstream is directly linked with MMP-9 expression. Deoxypodophyllotoxin (DPT), a naturally occurring flavolignan with anti-inflammatory activity, was isolated from Anthriscus sylvestris Hoffm. and has been known inhibit the expression of MMP-9 in tumor necrosis factor-alpha (TNF-alpha) stimulated human aortic smooth muscle cells (HASMC). In this study, DPT was purified and demonstrated to inhibit the MMP-9/2 activities in TNF-alpha-induced HASMC. In addition, MMP-9 expression and migration was strongly inhibited by DPT in TNF-alpha-induced HASMC. To examine whether TNF-alpha-induced MMP-9 expressions are involved with migrations of HASMC, reverse transcription-polymerase chain reaction (RT-PCR) and luciferase-tagged promoter analysis were applied. These experiments revealed that DPT inhibited the mRNA transcription of MMP-9 gene expression. Furthermore, Western blot analysis indicated that the TNF-alpha-induced phosphorylation of extracellular signal regulated kinase 1 and 2 (ERK1/2), p38 and c-Jun N-terminal kinase (JNK) were strongly inhibited by DPT. From these results, it is concluded that DPT has an inhibitory activities on migration and MMP-2/9 activities, and MMP-9 transcription in HASMC.

Pimaric acid from Aralia cordata has an inhibitory effect on TNF-α-induced MMP-9 production and HASMC migration via down-regulated NF-κB and AP-1.

Many studies have indicated that activation of matrix metalloproteinase (MMP)-9 and smooth muscle cell (SMC) migration are involved in neointimal formation and atherosclerosis. In this study, we revealed that pimaric acid (PiMA) purified from Aralia cordata had an inhibitory effect on MMP-9 production and migration of human aortic smooth muscle cells (HASMCs) induced by tumor necrosis factor (TNF)-α. Down-regulated MMP-9 mRNA transcription was detected in PiMA-treated cells using RT-PCR and the luciferase-tagged MMP-9 promoter assay. Results of an electrophoretic mobility shift assay indicated that PiMA-treated HASMCs showed decreased binding activity of nuclear factor (NF)-κB and activator protein-1 transcription factors. A Western-blot analysis using nuclear extract demonstrated that PiMA reduced the levels of NF-κB p65, c-Fos, p-c-Jun, Jun-D, and p-ATF2 proteins in the nucleus. In addition, TNF-α stimulated mitogen activated protein kinase (MAPK) containing extracellular signal regulated kinase 1 and 2, p38, and c-Jun N-terminal kinase was inhibited by PiMA. Using the Transwell system, we found that PiMA inhibited TNF-α stimulated HASMC migration/invasion in a dose-dependent manner. To confirm whether MAPK mediated MMP-9 expression, we used MAPK inhibitors including U0126, SB253580, and SP600125 and found that those inhibitors reduced MMP-9 expression and HASMC migration/invasion. These results suggest that PiMA has potent anti-atherosclerotic activity with inhibitory action on MMP-9 production and cell migration in TNF-α-induced HASMCs.

Saucerneol D, a naturally occurring sesquilignan, inhibits LPS-induced iNOS expression in RAW264.7 cells by blocking NF-κB and MAPK activation

We evaluated the ability of saucerneol D (SD), a tetrahydrofuran-type sesquilignan isolated from Saururus chinensis, to regulate the expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-stimulated murine macrophage-like RAW264.7 cells. SD consistently inhibited nitric oxide (NO) production in a dose-dependent manner, with an IC(50) of 2.62 microM, and also blocked LPS-induced iNOS expression. SD potently suppressed both the reporter gene expression and DNA-binding activity of nuclear factor-kappaB (NF-kappaB). In addition, SD inhibited IkappaB-alpha degradation in a concentration- and time-dependent manner. SD also inhibited LPS-induced activation of various mitogen-activated protein kinases, including extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun NH(2)-terminal kinase (JNK). These findings suggest that SD may inhibit LPS-induced iNOS expression by blocking NF-kappaB and MAPK activation.

Anti-inflammatory effect of Ulmus davidiana Planch (Ulmaceae) on collagen-induced inflammation in rats

Ulmus davidiana Planch (Ulmaceae) extract (UD) has long been known to have anti-inflammatory and anticancer activities. UD has been also known to have protective effects on damaged tissue, inflammation and bone among other functions. Effects of UD on inflammatory and immune responses and its mechanisms in collagen-induced inflammation (CII) rat were studied. Hind paw volumes of rats were measured by volume meter; lymphocyte proliferation, interleukin (IL)-1, IL-2, tumor necrosis factor (TNF)-α level was determined by 3-(4,5-2dimethylthiazal-2yl)2,5-diphenyltetrazoliumbromide assay. Antibodies to collagen type II (BC-II) were determined by enzyme-linked immunosorbent assay. There was a marked secondary inflammatory response in CII model, which accompanied with the decrease of body weight and the weight of immune organs simultaneously. The administration of UD (20, 80, 150mg/kg, intragastrically×10 days) inhibited the inflammatory response and restored body weight and the weight of immune organs of CII rats. Lymphocyte proliferation and IL-2 production of CII rats increases, together with IL-1 and TNF-α in peritoneal macrophages and synoviocytes. The administration of UD (20, 80, 150mg/kg, 10 days) reduced above changes significantly. UD had no effect on the concentration of antibodies to BC-II. From the results, it was concluded that UD possesses anti-inflammatory and immunoregulatory activities and has a therapeutic effect on CII rats.

Citreorosein, a naturally occurring anthraquinone derivative isolated from Polygoni cuspidati radix, attenuates cyclooxygenase-2-dependent prostaglandin D2 generation by blocking Akt and JNK pathways in mouse bone marrow-derived mast cells.

In this study, we examined the effects of citreorosein (CIT), an anthraquinone component of Polygoni cuspidati radix (P. cuspidati, Polygonaceae), on cyclooxygenase (COX)-2 dependent prostaglandin (PG)D2 generation in mast cells, central effector cells of allergy and other inflammatory diseases. CIT strongly inhibited COX-2-dependent PGD2 generation in a concentration-dependent manner in mouse bone marrow-derived mast cells (BMMCs) stimulated with stem cell factor (SCF)/IL-10/LPS. In an effort to identify the mechanisms underlying the inhibition of COX-2-dependent PGD2 generation by CIT, we examined the effects of this compound on MAP kinases, Akt and NF-κB signaling pathways, which are essential for COX-2 induction. CIT inhibited nuclear translocation of the nuclear factor (NF)-κB p65 subunit and its cognate DNA-binding activity, which correlated with its inhibitory effects on the phosphorylation of Akt and IKK and subsequent phosphorylation and degradation of IκB. Furthermore, CIT significantly attenuated the DNA binding of activator protein (AP)-1 that regulates COX-2 expression through the reduction of the phosphorylation of c-Jun. Moreover, inhibition of PGD2 generation by CIT was accompanied by a decrease in phosphorylation of cytosolic phospholipase A2α. Taken together, the present study suggests that CIT represents a potential therapeutic approach for the treatment of inflammatory diseases.

Pharmacological characterization of orally active cholinesterase inhibitory activity of Prunus persica L. Batsch in rats

Prunus persica L. Batsch water extract (PPE) is a potent acetylcholinesterase (AChE) inhibitor screened for the treatment of Alzheimers disease. The effects of oral administration of the PPE were examined with comparison of those of selective butyrylcholinesterase inhibitors of 9-amino-1,2,3,4-tetrahydroacridine hydrochloride (tacrine) and tetraidopropylpyrophosphoramide (iso-OMPA) and a selective AChE inhibitor, donepezil, on the cholinesterase activity in the brain and plasma of rats. After the sequential solvent fractionation of the methanol extract of P. persica L. Batsch, the highest inhibitory fraction was that of chloroform (75%). The concentration that was required for 50% enzyme inhibition (IC50 value) was 5.6 μg/mL. for the chloroform fraction. Oral administration of PPE or tacrine caused a dose-dependent inhibition of brain and plasma cholinesterase activities. The ID50 values of these compounds for brain cholinesterase activity were 2.7 g/kg and 8.9 mg/kg, respectively. On the other hand, the ID50 values for plasma cholinesterase activity were 18.6 g/kg and 27.5 mg/kg, respectively. Thus, the ratios of the ID50 (plasma<brain) were 6.0 and 3.1, respectively. These results suggest that orally administered PPE satisfactorily penetrates into the brain and inhibits cholinesterase there and that PPE is a potent inhibitor of brain cholinesterase in comparison with plasma cholinesterase in vivo.