• Archives of Pharmacal Research
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• v.22 no.1
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• pp.55-59
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• 1999

Nitric oxide synthesized by inducible nitric oxide synthase (iNOS) has been implicated as a mediator of inflammation in rheumatic and autoimmune diseases. The effects of higenamine, a tetrahydroisoquinoline compound, on induction of NOS by bacterial lipopolysaccaride (LPS) were examined in murine peritoneal macrophages. LPS-induced nitrite/nitrate production was markedly inhibited by higenamine which at 0.01 mM, decreased nitrite/nitrate levels by $48.7{\pm}4.4%$This was comparable to the inhibition of LPS-induced nitrite/nitrate production by tetrandrin ($49.51{\pm}2.02%$). at the same concentration. Northern and Western blot analysis of iNOS expression demonstrated that iNOS expression was significantly attenuated following co-incubation of peritoneal macrophages with LPS (10 $\mu\textrm{g}$/m;; 18hrs) and higenamine (0.001, 0.,01 mM; 18hrs). These results suggest that higenamine can inhibit LPS-induced expression of iNOS mRNA in murine peritoneal macrophages. The clinical implications of these findings remain to be established.

• Journal of Microbiology and Biotechnology
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• v.19 no.5
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• pp.439-446
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• 2009

The biosynthesis study of antibiotics saframycin (SFM) in Streptomyces lavendulae and safracin (SAC) in Pseudomonas fluorescens demonstrated that 3-hydroxy-S-methyl-O-methyltyrosine (3hSmOmTyr), a nonproteinogenic amino acid, is the precursor of the tetrahydroisoquinoline molecular core. In the biosynthetic gene cluster of SAC/SFM, sacD/sfmD encodes a protein with high homology to each other but no sequence similarity to other known enzymes; sacF/sfmM2 and sacG/sfmM3 encode methyltransferases for C-methylation and O-methylation; and sacE/sfinF encodes a small protein with significant sequence similarity to the MbtH-like proteins, which are frequently found in the biosynthetic pathways of non ribosomal peptide antibiotics and siderophores. To address their function, the biosynthetic cassette of 3h5mOmTyr was heterologously expressed in S. coelicolor and P. putida, and an in-frame deletion and complementation in trans were carried out. The results revealed that (i) SfmD catalyzes the hydroxylation of aromatic rings; (ii) sacD/sacF/sacG in the SAC gene cluster and sfmD/sfmM2/sfmM3 in the SFM cluster are sufficient for the biosynthesis of 3h5mOmTyr; and (iii) the mbtH-like gene is not required for the biosynthesis of the 3h5mOmTyr precursor.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.4
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• pp.325-331
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• 2000

Tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$ plays important roles in inflammatory responses. Some of tetrahydroisoquinoline (THI) compounds exhibited to inhibit iNOS expression in animal studies and RAW 264.7 cells, but the action of THI on inflammatory reaction was not fully investigated. In the present study, we examined a limited series of THIs (higenamine, YS-51 and THI-52) on the $TNF-{\alpha}$ mRNA expression in mouse peritoneal macrophages by Northern analysis. When thioglycollate-stimulated peritoneal macrophages were incubated with LPS (100 ng/ml), expression of $TNF-{\alpha}$ mRNA was evident and reached its maximum at 2.5 h, which was reduced concentration-dependently by treatment with THIs. When the $TNF-{\alpha}$ activity of macrophage-conditioned media was measured using a TNF-sensitive L929 fibroblast cell line, CCL 1, all THIs increased the cell viability in a concentration dependent manner. The concentrations of THIs used are not cytotoxic by itself when analysed by MTT. Furthermore, nitrite/nitrate level was significantly reduced by the presence of THIs in cells treated with $LPS+interferon-{\gamma}\;(IFN-{\gamma}).$ It is concluded, thus, that these results strongly indicated that THIs can suppress the $TNF-{\alpha}$ expression and reduce NO, which may be useful for the inflammatory disorders.

• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.143-148
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• 1995

Recently, we reported that GS 389 has vasodilating action without cardiac inotropic action (Chang et al., Can. J. Physiol. Pharmacol. 72, 327-334, 1994). However the mechanism of action of GS 389 has not been thoroughly evaluated. In the present study, we performed functional study of GS 389 in rat trachealis, thoracic aorta, pig coronary artery by isometric tension and in human platelets by aggregation experiments. We also tested if GS 389 influences on $Ca^{2+}$movement and inositol phosphate metabolism. In rat trachealis, GS 389 concentration-dependently relaxed carbachol (0.1 $\mu$M)- and high $K^{+}$(65.4 mM)-induced contraction with p$IC_{50}$/ of 4.43$\pm$ 0.19 and 4.11$\pm$0.12, respectively. In $Ca^{2+}$-free media, GS 389 inhibited carbachol-induced phasic contraction. In rat thoracic aorta, GS 389 inhibited $^{45}$ Ca uptake due to norepinephrine and high $K^{+}$, indicating that GS 389 has direct inhibitory action of $Ca^{2+}$movement. Furthermore, GS 389 competitively inhibited U46619-induced contraction in rat thoracic aorta and pig coronary artery with K, values of 5.23$\pm$0.12 and 5.56$\pm$0.14, respectively, and inhibited U 46619-induced phosphatidylinositide (PI) turnover in rat aorta. GS 389 also concentration-dependently inhibited the human platelet aggregation against U 46619 with p$IC_{50}$/ 5.66$\pm$0.02. These results indicate that GS 389 has thromboxane $A_2$ antagonistic action in vascular and platelets as well as direct action on $Ca^{2+}$ movement, which may account, at least in part, for relaxing action of rat trachealis. trachealis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.772-778
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• 2005

The chloromethyl-2-dihydroxyphosphinyl-6,7-dimethoxy-1,2,3,4-tetrahydro- isoquinoline (CDDT) is a newly synthesized derivative from 1,2,3,4-Tetra- hydroisoquinoline (THIQ). The THIQs include potent cytotoxic agents that display a range of antitumor activities, antimicrobial activity, and other biological properties. In this study, we investigated the effect of CDDT on the cytotoxicity, induction of apoptosis in human promyelocytic leukemia cells (HL-60 cells). CDDT showed a significant cytotoxic activity in HL-60 cells ($IC_{50}$ = approximately $37\;{\mu}g/ml$) at a 24 hr incubation. Treatment of HL-60 cells with CDDT displayed several features of apoptosis, including formation of DNA ladders in agarose gel electrophoresis, morphological changes of HL-60 cells with DAPI stain. Here we observed that CDDT caused activation of caspase-3, caspase-8, and caspase-9. The most efficacious time on the activation of caspases-3 was achieved at 12 hr. Further molecular analysis demonstrated that CDDT led to cleavage of poly(ADP-ribose) polymerase (PARP), increase of hypodiploid (Sub-G1) population in the flow cytometric analysis. In conclusion, these above results indicate that CDDT dramatically suppresses HL-60 cell growth by activation of caspase-3 with caspase-8, -9 activity. These data may support a pivotal mechanism for the use of CDDT in the prevention and treatment of leukemia.

• IMMUNE NETWORK
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• v.11 no.6
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• pp.420-423
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• 2011

Since CKD-712 has been developed as an anti-inflammatory agent, we examined the effect of CKD-712 during TLR4 signaling. Using HEK293 cells expressing TLR4, CKD-712 was pre-treated 1 hr before LPS stimulation. Activation of NF-${\kappa}B$ was assessed by promoter assay. The activation of ERK, JNK, p38, IRF3 and Akt was measured by western blotting. CKD-712 inhibited the NF-${\kappa}B$ signaling triggered by LPS. The activation of ERK, JNK, p38 or IRF3 was not inhibited by CKD-712. On the contrary the activation of these molecules was augmented slightly. The activation of Akt with stimulation of LPS was also enhanced with CKD-712 pre-treatment at lower concentration, but was inhibited at higher concentration. We suggest that during TLR4 signaling CKD-712 inhibits NF-${\kappa}B$ activation. However, CKD-712 augmented the activation of Akt as well as Map kinases. Therefore, we suggest that CKD-712 might have a role as an immunomodulator.

• Biomolecules & Therapeutics
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• v.5 no.3
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• pp.239-245
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• 1997

Trimetoquinol (TMQ) and its analogs are known to have thromboxane $A_2$ antagonistic action. We also reported that GS389, chemically similar to TMQ, has competitive antagonistic action in rat aorta and human platelets. In the present study, we investigated the pharmacological characteristics of GS283 and GS 386, analogs of GS389, using vascular smooth muscle, human platelets and rat brain homogenates. In isolated pig coronary artery (PCA), both of GS283 and GS386 relaxed U46619-contracted rings in concentration dependent manner. Pretreatment with several concentrations of GS283 and GS386 shifted the dose-response curves to the right, and reduced of maximum contration dose-dependently. Furthermore, GS283 and GS386 strongly inhibited $Ca^{2+}$ -induced contraction in the PCA. In human platelets, U46619- and A23187-induced platelet aggregation was inhibited by GS283 and GS386, concentration-dependently. Anti-platelet aggregation was related to the compound\`s ability to inhibit ATP release at each stimulation. In rat brain homogenates, receptor-binding assay resulted that both GS283 and GS386 have a relative affinity to $\alpha$-adrenergic receptor. Taken together. we concluded that the mechamism of action of GS283 and GS86 is not related with in TXA$_2$ receptor but concerned with calcium antagonistic action and a-blocking action.n.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.5
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• pp.273-280
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• 2004

Nitric oxide (NO) has been suggested to act as a mediator of cytokine-induced effects of turn over of bone. Activation of the inducible nitric oxide synthase (iNOS) by inflammation has been related with apoptotic cell death in osteoblast. YS 49, a synthetic isoquinoline alkaloid, inhibits NO production in macrophages activated with cytokines. In the present study, we investigated the molecular mechanism of YS 49 to inhibit iNOS expression in ROS 17/2.8 cells, which were activated with combined treatment of inflammatory cytokines $(TNF-{\alpha},\;IFN-{\gamma})$ and lipopolysaccharide (LPS). Results indicated that YS 49 concentration-dependently reduced iNOS mRNA and protein expression, as evidenced by Northern and Western blot analysis, respectively. The underlying mechanism by which YS 49 suppressed iNOS expression was not to affect iNOS mRNA stability but to inhibit activation and translocation of $NF-_kB$ by preventing the degradation of its inhibitory protein $I_kB_{\alpha}$. As expected, YS 49 prevented NO-induced apoptotic cell death by sodium nitroprusside. Taken together, it is concluded that YS 49 inhibits iNOS expression by interfering with degradation of phosphorylated inhibitory $_kB_{\alpha}\;(p-I_kB_{\alpha})$. These actions may be beneficial for the treatment of inflammation of the joint, such as rheumatoid arthritis.

• The Korean Journal of Pharmacology
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• v.22 no.2
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• pp.96-104
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• 1986

Higenamine, dl-1-( 4-hydroxybenzyl)-6, 7-dihydroxy-1 ,2, 3 ,4-tetrahydroisoquinoline has been synthesized and evaluated for hemodynamic actions using rabbits under pentobarbital anesthesia. Concentration-related fall of mean blood pressure was observed, where diastolic blood presure was significantly lowered at 10 ug/kg/min or above (p<.05), while the systolic blood pressure was slightly increased or unaffected, thereby, causing increment of pulse pressure. No significant change was occured in heart rate, however, carotid artery blood flow was significantly (p<.05) increased. These actions were inhibited with pretreatment of 0.3 mg/kg of propranolol, beta-adrenoceptor antagonist, 5 minutes before infusion of higenamine indicating that higenamine compete with propranolol for the so-called beta adrenergic receptor. As comparison, the same procedure was applied to isoproterenol as well, where typical antagonism of propranolol against isoproterenol was shown. From these findings the vasodilating and diastolic blood pressure lowing effects could be explained in terms of cardiac beta stimulating action, however, dopamine receptor activation could not be excluded because no significant changes observed in chronotropism.