• The Korean Journal of Physiology and Pharmacology
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• 제13권5호
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• pp.337-341
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• 2009

Signal transducer and activator of transcription 4 (STAT4), a STAT family member, mediates interleukin 12 (IL12) signal transduction. IL12 is known to be related to calorie-restricted status. In the central nervous system, IL12 also enhances the production of nitric oxide (NO), which regulates food intake. In this study, the expression of neuronal NO synthase (Nos1), which is also related to food intake, was investigated in the hypothalamic areas of Stat4 knockout (KO) mice using nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry, a marker for neurons expressing Nos1 enzyme. Western blots were also performed to evaluate Nos1 and Fos expression. Wild-type Balb/c (WT group, n=10 male) and Stat4 KO mice (Stat4 KO group, n=8 male) were used. The body weight and daily food intake in the WT group were $22.4{\pm}0.3$ and 4.4 g per day, while those in the Stat4 KO group were $18.7{\pm}0.4$ and 1.8 g per day, respectively. Stat4 mice had lower body weight and food intake than Balb/c mice. Optical intensities of NADPH-d-positive neurons in the paraventricular nucleus (PVN) and lateral hypothalamic area (LHA) of the Stat4 KO group were significantly higher than those of the WT group. Western blotting analysis revealed that the hypothalamic Nos1 and Fos expression of the Stat4 KO group was up-regulated, compared to that in the WT group. These results suggest that Stat4 may be related to the regulation of food intake and expression of Nosl in the hypothalamus.

• Bulletin of the Korean Chemical Society
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• 제31권1호
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• pp.27-30
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• 2010

A series of thioureas were synthesized as inhibitors of NO production in lipopolysaccharide-activated macrophages. We investigated the effect of lipophilic moiety and N-substituents of the thioureas on the activity. Phenoxazine and carbazole-containing derivatives revealed higher activity than indole-containing thioureas. The appropriate spacer between lipophilic tail and thiourea head and methyl substituent at N3 position of thiourea brought beneficial effect on the inhibition of NO production. Among prepared compounds, phenoxazine-containing derivative 2a was the most potent with $2.32 {\mu}M$ of $IC_{50}$ value. RT-PCR analysis suggested that the prepared thioureas inhibited NO production through the suppression of iNOS mRNA expression.

• 한국식품영양과학회지
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• 제36권5호
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• pp.548-553
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• 2007

저자들은 일반 흰쥐를 1.5% cholesterol과 0.25% cholic acid, 우지 25% 첨가한 식이로 고지혈증을 유발시킨 후 KH-305를 8주간 경구투여하여 혈중 cholesterol과 HDL-C, LDL-C 등을 측정, 지질대사에 미치는 영향을 알아보았다. 또한, 최대해면체 내압과 내피 관련 NOS 발현정도를 측정하여 음경발기 촉진 및 지속에 미치는 영향을 알아보았다. 그 결과 KH-305를 투여한 모든 그룹에서 고지방식이 그룹보다 총 cholesterol 수치와 LDL-C를 낮추었으며 HDL-C의 수치를 높였다. 최대해면체 내압에서는 KH-305 투여 그룹이 고지방식이 그룹보다 최대해면체 내압에 이르는 시간이 짧았고 최대해면체 내압의 수치가 높았으며 이 중 300mg/kg일 경우 가장 효과가 좋았다. 또한, KH-305 모든 투여 그룹은 고지방식이 그룹과 비교해 볼 때 모든 그룹에서 eNOS와 nNOS의 발현이 뚜렷이 증가되었다. 따라서, 혈중 cholesterol을 낮추면서 NOS의 발현을 증가, 최대해면체 내압이 큰 KH-305는 고지혈증으로 유발된 발기부전에 효능이 있는 약물이 될 수 있으리라 사료된다.

• Archives of Pharmacal Research
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• 제25권5호
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• pp.697-703
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• 2002

We investigated that the role of nitric oxide (NO) on ischemic rats in brain and heart. Ischemia was induced by both common carotid arteries (CCA) occlusion for 24h following reperfusion. Then tissue samples were removed and measured NOx. In brain, NOx was increased by about 40% vs. normal and it was significantly inhibited by aminoguanidine, selective iNOS inhibitor. This result showed that NOx concentration was increased by iNOS. We investigated the role of $Ca^{2+}$ during ischemia. Nimodipine, L-type calcium channel blocker, didn't inhibit the increases of NOx concentration during ischemia. It suggested that increased NOx was due to calcium-independent NOS. MK-801, which N-methyl-D-aspartate (NMDA) receptor antagonist, didn't significantly prevent the increases of NOx. In heart, ischemia caused NOx decrease and it is inconsistent with NOx increase in brain. Aminoguanidine and nimodipine didnt affect on NOx decrease. But MK-801 more lowered NOx concentration than those of ischemia control group. It seemed that $Ca^{2+}$ influx in heart partially occurred via NMDA receptor and inhibited by NMDA receptor antagonist. The mean arterial pressure (MAP) in ischemic rats after 24h of CCA occlusion was decreased when compared to normal value, whereas the heart rates (HR) was not different between two groups. Aminoguanidine or MK801 had no effect on MAP or HR, but nimodipine reduced MAP. There was no difference the effects of aminoguanidine, nimodipine, or MK-801, on MAP and HR between normal rats and ischemic rats. In summary, ischemic model caused an increase of NOx concentration, suggesting that this may be produced via iNOS, which is calcium independent in brain. However in heart, ischemia decreased NOx concentration and NMDA receptor was partially involved. The basal MAP was decreased in ischemic rats but HR was not different from normal control, suggesting that increased NOx in brain of ischemic rat may result in the hypotension.

• Korean Journal of Acupuncture
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• 제21권1호
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• pp.113-127
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• 2004

Objectives : The usage of acupuncture has gained popularity as an alternative method of treatment for certain chronic pain conditions. However, the efficacy of acupuncture in various diseases has not been fully established and the underlying mechanism is not clearly understood. In the present study, the effect of electroacupuncture (EA) applied to foot samli$(ST_{36})$ on the carrageenan-induced knee arthritic pain was examined. Methods : A common source of persistent pain in humans is the knee arthritis. Knee arthritis was induced by injection of 2 % carrageenan $50\;{\mu}l$ into the knee joint cavity. When rats developed pain behaviors, EA was applied for 30 min. under enflurane anesthesia with repeated train stimuli at the intensity of 10X of muscle twitch threshold. The weight bearing force of the hind limb was measured for an indicator of pain level after each manipulation. Results : The average weight borne by the hind limb during normal gait was 55% of total body weight, which was reduced to less than 10% after knee arthritis. EA improved the weight bearing of the arthritic hind limb significantly for the duration of 4 hr. EA applied to $ST_{36}$ point produced a significant improvement of stepping force of the arthritic foot lasting for at least 4 h. However, $GB_{31}$ point did not produce any significant increase of weight bearing force. The analgesic effect was specific to the acupuncture point since the analgesic effect on the knee arthritis model could not be mimicked by EA applied to a nearby point, $GB_{31}$. The relations between EA-induced analgesia and endogenous nitric oxide(NO) and inducible NO synthase(iNOS)/neuronal NOS was also examined. Results were turned out that both NO production and nNOS/iNOS protein expression which is increased by arthritis were suppressed by EA stimulation applied to $ST_{36}$ point. Conclusions : The data suggest 1) that EA produces a potent analgesic effect on the rat model of chronic knee arthritis pain in a point specific manner and 2) that EA-induced analgesia modulate endogenous NO through the suppression of nNOS/iNOS protein expression.

• Journal of Trauma and Injury
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• 제19권1호
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• pp.14-20
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• 2006

Purpose: Although hypothermia has been used in many clinical situations, such as post cardiopulmonary resuscitation, stroke, traumatic brain injury, septic shock, and hemorrhagic shock, the mechanism by which it works has not been clearly elucidated. We aimed to evaluate the effect of hypothermia on the plasma nitric oxide (NO) concentration, lung iNOS expression, and histologic changes in intestinal ischemia-reperfusion (IR). Method: Male Sprague-Dawley rats were randomly divided into the hypothermia group (HT, n=8, $27{\sim}30^{\circ}C$) and the normothermia group (NT, n=8, $36{\sim}37^{\circ}C$). They underwent 30 min of intestinal ischemia by clamping the superior mesenteric artery, which was followed by 1.5 h of reperfusion. They were then sacrificed. The acute lung injury (ALI) score, the plasma NO concentration, and lung iNOS gene expression were measured. Results: Compared with the HT group, the NT group showed severe infiltrations of inflammatrory cells, alveolar hemorrhages, and interstitial hypertrophies in lung tissues. There were significant differences in the ALI scores between the NT and the HT groups ($8.7{\pm}1.5/HPF$ in NT vs $5.8{\pm}1.2/HPF$ in HT, p=0.008). Although the plasma NO concentration was slightly lower in the HT group, there was no significant difference between the two groups ($0.80{\pm}0.24{\mu}mol/L$ in NT vs $0.75{\pm}0.30{\mu}mol/L$ in HT, p=0.917). Lung iNOS gene expression was stronger in the NT group than in the HT group. The band density of the expression of iNOS in lung tissues was significantly increased in the NT group compared to the HT group ($5.54{\pm}2.75$ in NT vs$0.08{\pm}0.52$ in HT, p=0.002). Conclusions: This study showed that hypothermia in intestinal IR reduces inflammatory responses, ALI scores, and iNOS gene expression in lung tissues. There was no significant effect of hypothermia on the plasma NO concentration.

• Natural Product Sciences
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• 제24권3호
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• pp.171-180
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• 2018

Artemisia capillaris has been widely used as an alternative therapy for treating obesity and atopic dermatitis. It has been used as a hepatoprotactant. It is also used for ameliorating inflammatory reactions. Although there are several investigations on other Artemisia species, there is no systematic study describing the role of A. capillaris MeOH extract, its solvent soluble fractions, or derived anti-inflammatory principal components in regulating inflammatory conditions. Therefore, the objective of this study was to elucidate anti-inflammatory mechanisms of A. capillaris. Results revealed that MeOH extract of A. capillaris could decrease LPS-stimulated NO secretion. Of tested fractions, $CH_2Cl_2$, EtOAc, and n-BuOH strongly inhibited NO release from RAW264.7 cells. Bioactive mediators derived from $CH_2Cl_2$ and n-BuOH fractions elicited potent anti-inflammatory actions and strikingly abrogated LPS-triggered NO accumulation in RAW264.7 cells. Of particular interest, capillin and isoscopoletin possessed the most potent NO suppressive effects. Western blot analysis validated the molecular mechanism of NO inhibition and showed that capillin and isoscopoletin significantly down-regulated iNOS and COX-2 protein expression. Taken together, our results provide the first evidence that MeOH extract, $CH_2Cl_2$, EtOAc, and n-BuOH fractions from A. capillaris and its derived lead candidates can potently suppress inflammatory responses in macrophages by hampering NO release and down-regulating iNOS and COX-2 signaling.

• 대한한의학회지
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• 제24권2호
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• pp.138-147
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• 2003

Objectives : In this study, we investigated the mechanism by which Chelidonium majus (CM) regulates nitric oxide (NO) production. Methods : Using mouse peritoneal macrophages, the mechanism by which CM regulates NO or tumor necrosis $factor-{\alpha}(TNF-{\alpha})$ production was examined. NO release was measured by the Griess method. $TNF-{\alpha}$ production was measured by the ELISA method. The protein extracts were prepared and samples were analyzed for the inducible NOS(iNOS) expression and nuclear factor kappa $B(NF-{\kappa}B)$ activation by Western blotting. Results : When CM was used in combination with recombinant $interferon-{\gamma}{\;}(rIFN-{\gamma})$, there was a marked cooperative induction of NO production. CM had an effect on NO production by itself. The expression of the iNOS gene was increased in $rIFN-{\gamma}$ plus CM-stimulated peritoneal macrophages and almost completely inhibited by pre-treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of $NF-{\kappa}B$. The $NF-{\kappa}B$ activation was increased in rIFN-{\gamma} plus CM-induced peritoneal macrophages. The increased production of NO from $rIFN-{\gamma}$ plus CM-stimulated peritoneal rnacrophages was decreased by the treatment with $N^{G}-monomethyl-{_L}-arginine{\;}(N^{G}MMA){\;}N^{\alpha}-Tosyl-Phe$ chloromethyl ketone (TPCK) , and was almost completely inhibited by pre-treatment with PDTC. Furthermore, treatment with CM alone or rIFN-{\gamma} plus CM in peritoneal macrophages caused a significant increase in $TNF-{\alpha}$ production. PDTC decreased CM-induced $TNF-{\alpha}$ production significantly. After CM treatment in HT-29 or AGS cells, cell viability decreased. Conclusions : These findings demonstrate that CM increases the production of NO and $TNF-{\alpha}{\;}by{\;}rIFN-{\gamma}-primed$ macrophages and suggest that NF-B plays a critical role in mediating these effects of CM.

• Natural Product Sciences
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• 제23권3호
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• pp.162-168
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• 2017

Cordyceps bassiana has long been used as an oriental medicine and reported to possess diverse biological activities. The fruiting bodies of Cordyceps bassiana was extracted with ethanol and then further fractionated with n-hexane, ethyl acetate, n-butanol and water. The butanol fraction from Cordyceps bassiana (CBBF) exhibited the most effective in anti-inflammatory activity in RAW 264.7 macrophages and the roles of CBBF on the anti-inflammation cascade in LPS-stimulated RAW 264.7 cells were studied. To investigate the mechanism by which CBBF inhibits NO, iNOS and COX-2, the activation of $I{\kappa}B$ and MAPKs in LPS-activated macrophage were examined. Our present results demonstrated that CBBF inhibits NO production and iNOS expression in LPS-stimulated RAW 264.7 macrophage cells, and these effects were mediated through the inhibition of $I{\kappa}B-{\alpha}$, JNK and p38 phosphorylation. Also, CBBF suppressed activation of MAPKs including p38 and SAPK/JNK. Furthermore, CBBF significantly suppressed LPS-induced intracellular ROS generation. Its inhibition on iNOS expression, together with its antioxidant activity, may support its anti-inflammatory activity. Thus Cordyceps bassiana can be used as a useful medicinal food or drug for further studies.

• Korean Journal of Acupuncture
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• 제23권3호
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• pp.55-71
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• 2006

Objectives : The present study was investigated the effect and pathway of heterotopic electroacupuncture (EA) on pain induced by formalin in rats. Methods : Acupoints in the right forepaws, $HT_7$ and $PC_7$, were stimulated with 3 mA, 2 ms, and 10 Hz before subcutaneously formalin injection (5%, $50{\mu}l$) to the left hind paw. Moreover, it was investigated whether the dorsolateral funiculus (DLF), as known to the descending inhibition, mediates analgesia of the heterotopic EA, and an administration of naltrexone blocks the effect of EA. Results : In the immunohistochemistry of cFos-like protein (cFL), there were inhibitory effects of EA on the increased expression of cFL in the lumbar spinal dorsal horn neurons following formalin injection. Especially, EA inhibited the expression of cFL on the superficial laminae than that on the deep laminae at 1 hr after, but that on the deep laminae than that on the superficial laminae at 2 hr after. Also, EA suppressed the increased expression of nitric oxide (NO) and neuronal nitric oxide synthase (nNOS) in the lumbosacral spinal cord after formalin injection, but not Sham-EA. Suppressed expressions of cFL, NO and nNOS in the spinal cord were eliminated after transection of the ipsilateral DLF at $T_{10}{\sim}T_{11}$ levels. However, pretreatment of naltrexone could not prevent the suppressive expressions of cFL, NO and nNOS at the spinal cord. Conclusions : These results suggest that the analgesia of heterotopic EA may be modulated through the DLF constituting the descending inhibition.