• Archives of Pharmacal Research
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• 제12권4호
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• pp.276-281
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• 1989

Selective inhibition of seven new PDE inhibitors on cyclic nucleotide PDE isozymes was investigated. Three PDE isozymes (PDE I, II and III) of guinea pig left ventricular muscles were used. All tested agents inhibited cyclic AMP hydrolysis by PDE III IN A concentration-dependent manner. Some agents represented more potent and selective inhibitory effect on PDE III than that of imazodan.

• 대한수의학회지
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• 제43권4호
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• pp.615-624
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• 2003

Vascular smooth muscle relaxation is modulated by an increase in cGMP subsequent to nitric oxide (NO) production by endothelial cells. The effects of cAMP and cGMP phosphodiesterase (PDE) inhibitors were investigated in phenylephrine-precontracted rat aorta rings by using the specific inhibitors of PDE I, III, IV and V as relaxing agents (calmodulin-activated PDE inhibitors, IBMX and $W_7$, type I; cAMP-specific PDE inhibitors, milrinone, type IV; Ro 20-1724, type III and cGMP-specific PDE inhibitor, zaprinast, type V). All the PDE inhibitors produced a concentration-dependent relaxation in the ring with intact endothelium (+E). Except for milrinone, all the PDE inhibitors-induced relaxations were inhibited by removal of extracellular $Ca^{2+}$, $N^G$-nitro-L-arginine, $N^G$-nitro-L-arginine methyl ester, methylene blue (MS) or nifedipine. The specific PDE I and PDE IV inhibitors both produced endothelium-independent relaxations which were inhibited by MS in -E rings. However, zaprinast had no effect in -E rings. Except for milrinone, sodium nitroprusside (a NO donor)-induced relaxation was significantly augmented by all PDE inhibitors in +E rings. The results suggest that I) the vasorelaxant properties of IBMX, $W_7$, Ro 20-1724 and zaprinast are dependent on endothelium or on interaction with $Ca^{2+}$ regulation, 2) each PDE is differently distributed in vascular tissues (endothelial and smooth muscle cells), 3) the vasodilations of PDE inhibitors are due to the increase of cAMP and cGMP formation through inhibition of cAMP- and cGMP-PDE and 4) the vasodilation action of milrinone does not involve in endothelial-cyclic nucleotide system.

• Archives of Pharmacal Research
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• 제25권6호
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• pp.873-878
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• 2002

OA-8159, a new Phosphodiesterase (PDE) 5 inhibitor, has exhibited potent erectogenic potential in a penile erection test in rats and anesthetized dogs. In this study, we investigated the mechanism of its erectogenic activity by measuring the activity of OA-8159 against a various PDE isozymes and assessing cGMP and cAMP formation in a rabbit corpus cavernosum in vitro. DA-8159 inhibited the PDE 5 activity in rabbit and human platelets, which the $IC_{50}$ was 5.84$\pm$1.70 nM and 8.25$\pm$2.90 nM, respectively. The $IC_{50}$ of DA-8159 on PDE 1, PDE2, PDE 3 and PDE 6 were 870$\pm$57.4 nM, $101\pm$5 $\mu$M, 52.0$\pm$3.53 $\mu$M and 53.3$\pm$2.47 nM, respectively. This suggests that DA-8159 is a potent, highly selective, competitive inhibitor of PDE 5-catalyzed cGMP hydrolysis. The rates of cGMP hydrolysis catalyzed by human platelets-derived PDE 5 as a function of the cGMP concentration (5~100 nM) and two-fixed DA-8159 concentration (11.3 and 18.8 nM) were investigated in order to characterize the mode of PDE 5 inhibition by DA-8159. DA-8159 increased the apparent 4K_{m}$ value for cGMP hydrolysis but had no effect on the apparent $V_{max}$, indicating a competitive mode of inhibition. DA-8159 increased the cGMP concentrations in the rabbit corpus cavernosum dose dependently. In the presence of sodium nitroprusside (SNP), DA-8159 significantly sti\mulated the accu\mulation of cGMP when compared to the control level. This indicated that the enhancement of a penile erection by DA-8159 involved the relaxation of the cavernosal smooth \muscle by NO-sti\mulated cGMP accu\mulation. In conclusion, DA-8159 is a selective inhibitor of PDE 5-catalyzed cGMP hydrolysis and the enhancement of a penile erection by DA-8159 is mediated by the relaxation of the cavernosal smooth \muscle by the NO-sti\mulated cGMP accu\mulation.

• 생명과학회지
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• 제26권12호
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• pp.1355-1359
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• 2016

인간 중간엽 줄기세포(hMSCs)는 신경세포(neuron-like cells)를 포함한 다양한 세포로 분화할 수 있는 능력을 지닌 성체 줄기세포(adult stem cells)이다. 본 연구에서는 인간의 골수유래-중간엽 줄기세포(bone marrow-mesenchymal stem cells; hBM-MSCs)를 이용한 신경분화에서 신경세포 표지자(neuronal marker)인 NF-M, Tuj-1 뿐만 아니라 성상세포 표지자(glial marker)인 GFAP의 발현 역시 의미 있게 증가함을 real-time PCR, Western blot, and immunocytochemical staining법을 통하여 관찰하였다. 이를 개선하기 위하여, 신경분화에 중요한 신호전달자(signal intermediator)인 PDE4를 억제한 후 신경분화를 유도하였다. PDE4 억제자인 rolipram 혹은 resveratrol를 각각 처리하여 신경분화한 줄기세포(Roli- or RSV-dMSCs)에서 NF-M, Tuj-1의 발현이 증가하였고 반면, GFAP의 발현은 감소함을 real-time PCR, Western blot, and immunocytochemical staining법을 통하여 관찰하였다. 본 연구를 통하여, PDE4를 조절하며 줄기세포의 신경분화를 개선할 수 있음을 보였다.

• 생약학회지
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• 제45권3호
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• pp.268-274
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• 2014

The aim of this study is to explore the potent phosphodiesterase 4 and 7 inhibitor from various herbal medicines for atopy treatment. In this study, 51 kinds of each herbal medicine, which were extracted with ethanol, was carried out the screening of PDE 4 and 7 inhibition using enzyme inhibitory assay. Of these, 8 species of herbal medicines, Rubus coreanus, Duchesnea chrysantha, Alisma orientale, Rehmannia glutinosa, Angelica dahurica, Thuja orientalis, Astragalus membranaceus and Perilla frutescens were screened as potential inhibitor against PDE 4 and 7. Among 8 species, Duchesnea chrysantha showed poteinial anti-atopic effect on DNCB-induced atopic model. Duchesnea chrysantha extract decreased serum IgE and histamine release significantly.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 춘계학술발표회
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• pp.81-81
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• 2018

The present study was investigated on in vitro anti-obesity effect of 4-hydroxybenzyl alcohol from Cudrania tricuspidata. We isolated various compounds from Cudrania tricuspidata. Among these compounds, anti-obesity effects of 4-hydroxybenzyl alcohol was examined by lipase activity assay, cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase type IV (PDE4) activity assay, and citrate synthase activity assay. 4-hydroxybenzyl alcohol and Cudrania tricuspidata extracts inhibited the enzymatic activities of lipase, PDE4, and citrate synthase. Lipase is known to mediate the hydrolysis of triacylglycerol in adipose tissue and cholesterol esters in other tissue or cells. Also, PDE4 hydrolyses cAMP, a crucial secondary messenger for in metabolic pathways including glucose and lipid metabolism, lipolysis, and thermogenic function. 4-hydroxybenzyl alcohol and Cudrania tricuspidata extracts induced the inhibitory effect against each enzymatic activity on several specific substrates as observed by detection at 405 or 412 nm. These findings might be attributable to the inhibition of adipogenesis, and partial prevention of obesity. In conclusion, these results show that 4-hydroxybenzyl alcohol and Cudrania tricuspidata may be a critical candidate as a natural anti-obesity source.

• Archives of Pharmacal Research
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• 제23권4호
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• pp.332-337
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• 2000

This study describes the synthesis, in vitro evaluation and molecular modeling study of novel compounds for the inhibition of TNF-$\alpha$production, Among these compounds, 2-[3-(cyclopentyloxy)-4-methoxyphenyl]-1-isoindolinone (9) was selected as a lead compound and its pyridine derivative 10 was more potent in activity and safer than rolipram.

• 대한한방내과학회지
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• 제37권4호
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• pp.591-600
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• 2016

Objective: This study aimed to examine the relaxation effects and underlying mechanisms of Cynomorii herba (CH) extract in isolated rabbit corpus cavernous tissues.Methods: We experimented with CH extract (0.01-3.0 mg/mL). Nω-nitro-L-arginine (L-NNA) was experimented before the CH extract to contracted strips induced by phenylephrine (PE, 1 μM)and compared with nonexperimented. In addition, we experimented with calcium chloride (Ca²⁺, 1 mM) after pretreatment of the CH extract in Ca²⁺-free Krebs-Ringer solution to contracted strips induced by PE. The cell viability and nitric oxide (NO) concentration of human umbilical vein endothelial cells (HUVECs) were measured by an methylthiazol-2-yl-2, 5-diphenyl tetrazoliumbromide (MTT) assay and Griess reagent system. The ratio of smooth muscles to collagen fibers, in addition to eNOS- and PDE-5-positive reactions, was examined by histochemical and immunohistochemical staining.Results: The CH extract significantly induced the relaxation of the cavernous strips, and the pretreatment with L-NNA inhibited CH extract-induced relaxation. The L-NNA pretreatment reduced the increased contraction induced by the addition of Ca²⁺in Ca²⁺-free solution. Furthermore, the NO concentration of the HUVECs increased. When the CH extract was applied to the corpus cavernosum of the penis (CCP) of Sprague Dawley rats, the ratio of smooth muscles to collagen fibers by PE and the formation of eNOS around the helicine artery increased. However, the CH extract treatment decreased PDE-5 positive reactions.Conclusions: These results show that the relaxation effects induced by the CH extract are associated with the suppression of the influx of extracellular Ca²⁺ via the production of NO and eNOS and inhibition of PDE-5.

• Biomolecules & Therapeutics
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• 제28권4호
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• pp.328-336
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• 2020

Diabetes mellitus affects the colonic motility developing gastrointestinal symptoms, such as constipation. The aim of the study was to examine the role of intracellular signaling pathways contributing to colonic dysmotility in diabetes mellitus. To generate diabetes mellitus, the rats were injected by a single high dose of streptozotocin (65 mg/kg) intraperitoneally. The proximal colons from both normal and diabetic rats were contracted by applying an electrical field stimulation with pulse voltage of 40 V in amplitude and pulse duration of 1 ms at frequencies of 1, 2, 4, and 6 Hz. The muscle strips from both normal rats and rats with diabetes mellitus were pretreated with different antagonists and inhibitors. Rats with diabetes mellitus had lower motility than the control group. There were significant differences in the percentage of inhibition of contraction between normal rats and rats with diabetes mellitus after the incubation of tetrodotoxin (neuronal blocker), atropine (muscarinic receptor antagonist), prazosin (α₁ adrenergic receptor antagonist), DPCPX (adenosine A1 receptor antagonist), verapamil (L-type Ca²⁺ channel blocker), U73122 (PLC inhibitor), ML-9 (MLCK inhibitor), udenafil (PDE₅ inhibitor), and methylene blue (guanylate cyclase inhibitor). The protein expression of p-MLC and PDE₅ were decreased in the diabetic group compared to the normal group. These results showed that the reduced colonic contractility resulted from the impaired neuronal conduction and decreased muscarinic receptor sensitivity, which resulted in decreased phosphorylation of MLC via MLCK, and cGMP activity through PDE₅.

• 한국식품영양과학회지
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• 제38권12호
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• pp.1724-1731
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• 2009

마카, 홍삼, 남가새 추출물을 일정한 무게 비율로 혼합하여 발효시켜 얻어진 식물추출복합발효물(MP119)이 성기능에 미치는 영향을 조사하였다. ACE(angiotensin converting enzyme)과 PDE(phosphodiesterase)에 대한 저해효과를 통해 혈액순환부진 개선 및 cGMP 농도에 의한 발기능 개선에 미치는 효과를 측정하였다. MP119의 ACE 저해효과를 측정한 결과 $IC_{50}$값이 241.3${\pm}$35.5 ppm, PDE 저해효과를 측정한 결과 $IC_{50}$값이 372.2${\pm}$33.8 ppm으로 나타나 혈관확장으로 인한 혈류량 증가 및 cGMP농도 증가에 영향을 줄 수 있을 것으로 예상된다. MP119는 마우스 정소세포인 TM3 cell에 유의성 있는 독성이 나타나지 않았으며, TM3 cell에 농도별로 처리했을 때 세포배양액으로부터 대조군과 비교하여 최대 20.11% 증가한 testosterone 농도를 확인하였다. 또한 HUVEC에 농도별로 처리했을 때 NO생산량이 MP119 처리 농도가 증가할수록 유의성 있게 증가하였다. 웅성마우스에 MP119를 7일간 경구투여 후 생식장기의 무게와 정자수를 측정하고, MP119를 경구투여한 후 염화카드뮴을 투여하여 생식장기의 무게와 정자수를 측정하였다. 또한 실험쥐로부터 혈청을 분리하여 혈청 내 testosterone과 cGMP를 측정하였다. 그 결과 MP119의 투여를 통해 생식장기의 무게 변화 없이 정자수 증가에 도움을 준다는 것을 확인하였으며, 더불어 혈청 내 testosterone 및 cGMP의 농도 역시 증가하였다. MP119를 투여한 후 염화카드뮴을 투여한 실험군에서 역시 정자수 및 혈청 내 testosterone, cGMP 농도 증가를 나타내었으므로 결과적으로 MP119가 염화카드뮴의 독성예방 및 치료에 효과적임을 확인하였다.