Inhibitory effect of nitric oxide on the replication of a murine retrovirus in vitro and in vivo.

The aim of the present study was to investigate the effect of hydrogen sulfide (H2S) signaling by nitric oxide (NO) in isolated rat aortas and cultured human umbilical vein endothelial cells (HUVECs). Both administration of H2S and NaHS, as well as endogenous H2S, reduced NO formation, endothelial nitric oxide synthase (eNOS) activity, eNOS transcript abundance, and l-arginine (l-Arg) transport (all P < 0.01). The kinetics analysis of eNOS activity and l-Arg transport showed that H2S reduced Vmax values (all P < 0.01) without modifying Km parameters. Use of selective NOS inhibitors verified that eNOS [vs. inducible NOS (iNOS) and neuronal NOS (nNOS)] was the specific target of H2S regulation. H2S treatment (100 μmol/l) reduced Akt phosphorylation and decreased eNOS phosphorylation at Ser1177. H2S reduced l-Arg uptake by inhibition of a system y+ transporter and decreased the CAT-1 transcript. H2S treatment reduced protein expression of eNOS but not of nNOS and iNOS. Pinacidil (KATP channel opener) exhibited the similar inhibitory effects on the l-Arg/NOS/NO pathway. Glibenclamide (KATP channel inhibitor) partly blocked the inhibitory effect of H2S and pinacidil. An in vivo experiment revealed that H2S downregulated the vascular l-Arg/eNOS/NO pathway after intraperitoneal injection of NaHS (14 μmol/kg) in rats. Taken together, our findings suggest that H2S downregulates the vascular l-Arg/NOS/NO pathway in vitro and in vivo, and the KATP channel could be involved in the regulatory mechanism of H2S.

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Nitric oxide as a putative nonadrenergic noncholinergic inhibitory transmitter in the canine pylorus in vivo

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1992.262.4.g695 ◽

1992 ◽

Vol 262 (4) ◽

pp. G695-G702 ◽

Cited By ~ 8

Author(s):

H. D. Allescher ◽

G. Tougas ◽

P. Vergara ◽

S. Lu ◽

E. E. Daniel

Keyword(s):

Nitric Oxide ◽

Sodium Nitroprusside ◽

Vagal Stimulation ◽

Inhibitory Effect ◽

Field Stimulation ◽

Neural Inhibition ◽

Anesthetized Dogs ◽

Inhibitory Transmitter

Antropyloroduodenal motility was recorded in seven anesthetized dogs to assess the role of nitric oxide and L-arginine metabolites in nonadrenergic noncholinergic (NANC) mediation of pyloric relaxation. Pyloric activity induced by duodenal field stimulation was inhibited by antral field stimulation and electrical vagal stimulation. Intra-arterial NG-L-arginine-methyl-ester (L-NAME) reduced the inhibition from antral or vagal stimulation (P less than 0.05). Intravenous infusion of L-NAME also blocked the inhibitory effect of vagal and antral stimulation but left the tetrodotoxin-insensitive action of intra-arterial vasoactive intestinal peptide (VIP) and sodium nitroprusside unchanged. L-Arginine reversed the effect of L-NAME whereas D-arginine did not. L-NAME enhanced pyloric contractions to intra-arterial acetylcholine. The NANC inhibition of the substance P-stimulated pyloric response in vitro was blocked by L-NAME and reversed by addition of L-arginine. Sodium nitroprusside was effective as a relaxant in vitro but VIP was not. These data suggest that metabolites of L-arginine mediate neural inhibition of canine pyloric motor activity.

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Vasorelaxant-Mediated Antihypertensive Effect of the Leaf Aqueous Extract from Stephania abyssinica (Dillon & A. Rich) Walp (Menispermaceae) in Rat

BioMed Research International ◽

10.1155/2021/4730341 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Chamberlin Fodem ◽

Elvine Pami Nguelefack-Mbuyo ◽

Magloire Kanyou Ndjenda II ◽

Albert Kamanyi ◽

Télesphore Benoit Nguelefack

Keyword(s):

Nitric Oxide ◽

Heart Rate ◽

Methylene Blue ◽

Aqueous Extract ◽

Calcium Release ◽

Inhibitory Effect ◽

Antihypertensive Activity ◽

Phytochemical Analysis

Stephania abyssinica is a medicinal plant used in Cameroon alternative medicine to treat arterial hypertension (AHT). Previous in vitro studies demonstrated the endothelium nitric oxide-independent vasorelaxant property of the aqueous extract from Stephania abyssinica (AESA). But its effect on AHT is unknown. The present study was undertaken to explore other vasorelaxant mechanisms and to determine the antihypertensive effects of AESA in male Wistar rats. Phytochemical analysis of AESA was carried out using the liquid chromatography-mass spectrometry (LC-MS) method. The vasorelaxant effects of AESA (1-1000 μg/mL) were studied on rat isolated thoracic aorta rings, in the absence or presence of indomethacin (10 μM) or methylene blue (10 μM). The inhibitory effect of AESA on phenylephrine (PE, 10 μM) or KCl- (60 mM) induced contraction as well as the intracellular calcium release was also evaluated. The in vivo antihypertensive activity of AESA (43, 86, or 172 mg/kg/day) or captopril (20 mg/kg/day) administered orally was assessed in L-NAME- (40 mg/kg/day) treated rats. Blood pressure and heart rate (HR) were measured at the end of each week while serum or urinary nitric oxide (NO), creatinine, and glomerular filtration rate (GFR) were determined at the end of the 6 weeks of treatment, as well as histological analysis of the heart and the kidney. The LC-MS profiling of AESA identified 9 compounds including 7 alkaloids. AESA produced a concentration-dependent relaxation on contraction induced either by PE and KCl, which was significantly reduced in endothelium-denuded vessels, as well as in vessels pretreated with indomethacin and methylene blue. Moreover, AESA inhibited the intracellular Ca2+ release-induced contraction. In vivo, AESA reduced the AHT, heart rate (HR), and ventricular hypertrophy and increased serum NO, urine creatinine, and GFR. AESA also ameliorated heart and kidney lesions as compared to the L-NAME group. These findings supported the use of AESA as a potential antihypertensive drug.

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A Review ofIn VitroandIn VivoStudies on the Efficacy of Herbal Medicines for Primary Dysmenorrhea

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2014/296860 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 6

Author(s):

Kyoung-Sun Park ◽

Kang-In Park ◽

Deok-Sang Hwang ◽

Jin-Moo Lee ◽

Jun-Bock Jang ◽

...

Keyword(s):

Nitric Oxide ◽

Somatostatin Receptor ◽

Herbal Medicines ◽

Inhibitory Effect ◽

Phospholipid Metabolism ◽

Reproductive Age ◽

Herbal Formula ◽

Primary Dysmenorrhea

Purpose. Primary dysmenorrhea (PD) is a common gynecological complaint among adolescent girls and women of reproductive age. This study aims to review the findings of published articles on thein vitroandin vivoefficacy of herbal medicines for PD.Methods.In vitroandin vivostudies of herbal compounds, individual herbal extracts, or herbal formula decoctions published from their inception to April 2014 were included in this review.Results. A total of 18 studies involving herbal medicines exhibited their inhibitory effect on PD. The majority ofin vitrostudies investigated the inhibition of uterine contractions.In vivostudies suggest that herbal medicines exert a peripheral analgesic effect and a possible anti-inflammatory activity via the inhibition of prostaglandin (PG) synthesis. The mechanisms of herbal medicines for PD are associated with PG level reduction, suppression of cyclooxygenase-2 expression, superoxide dismutase activation and malondialdehyde reduction, nitric oxide, inducible nitric oxide synthase, and nuclear factor-kappa B reduction, stimulation of somatostatin receptor, intracellular Ca2+reduction, and recovery of phospholipid metabolism.Conclusions. Herbal medicines are thought to be promising sources for the development of effective therapeutic agents for PD. Further investigations on the appropriate herbal formula and their constituents are recommended.

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The Inhibitory Effect of Ojeoksan on Early and Advanced Atherosclerosis

Nutrients ◽

10.3390/nu10091256 ◽

2018 ◽

Vol 10 (9) ◽

pp. 1256 ◽

Cited By ~ 2

Author(s):

Byung Han ◽

Chang Seo ◽

Jung Yoon ◽

Hye Kim ◽

You Ahn ◽

...

Keyword(s):

Nitric Oxide ◽

Vascular Dysfunction ◽

Umbilical Vein ◽

Vascular Inflammation ◽

Inhibitory Effect ◽

Western Diet ◽

No Production ◽

Necrosis Factor Alpha

Atherosclerosis is closely related to vascular dysfunction and hypertension. Ojeoksan (OJS), originally recorded in an ancient Korean medicinal book named “Donguibogam”, is a well-known, blended herbal formula. This study was carried out to investigate the beneficial effects of OJS on atherosclerosis in vitro and in vivo. Western-diet-fed apolipoprotein-E gene-deficient mice (ApoE −/−) were used for this study for 16 weeks, and their vascular dysfunction and inflammation were analyzed. OJS-treated ApoE −/− mice showed lowered blood pressure and glucose levels. The levels of metabolic parameters with hyperlipidemia attenuated following OJS administration. Hematoxylin and eosin (H&E) staining revealed that treatment with OJS reduced atherosclerotic lesions. OJS also suppressed the expression of adhesion molecules and matrix metalloproteinases (MMPs) compared to Western-diet-fed ApoE −/− mice and tumor necrosis factor-alpha (TNF-α)-stimulated human umbilical vein endothelial cells (HUVECs). Expression levels of MicroRNAs (miRNA)-10a, -126 3p were increased in OJS-fed ApoE −/− mice. OJS significantly increased the phosphorylation of endothelial nitric oxide synthase (eNOS) and protein kinase B (Akt), which are involved in nitric oxide (NO) production. OJS also regulated eNOS coupling by increasing the expression of endothelial GTP Cyclohydrolase-1 (GTPCH). Taken together, OJS has a protective effect on vascular inflammation via eNOS coupling-mediated NO production and might be a potential therapeutic agent for both early and advanced atherosclerosis.

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Ptgs2 activation by endotoxin mediates the decrease in Igf1, but not in Igfbp3, gene expression in the liver

Journal of Endocrinology ◽

10.1677/joe-08-0205 ◽

2008 ◽

Vol 198 (2) ◽

pp. 385-394 ◽

Cited By ~ 4

Author(s):

A I Martín ◽

M López-Menduiña ◽

E Castillero ◽

M Granado ◽

M A Villanúa ◽

...

Keyword(s):

Gene Expression ◽

Nitric Oxide ◽

Direct Action ◽

Primary Cultures ◽

Inhibitory Effect ◽

Liver Cells ◽

Male Wistar Rats ◽

Igf Binding

The aim of this work was to analyse the role of cyclooxygenase-2 (Ptgs2) in endotoxin-induced decrease in Igf1 and Igf binding protein-3 (Igfbp3). For this purpose, male Wistar rats were injected with lipolysaccharide (LPS) and/or the Ptgs2 inhibitor meloxicam. LPS induced a significant decrease (P<0.01) in serum concentrations of Igf1 and Igfbp3 and their mRNAs in the liver. Meloxicam administration prevented the inhibitory effect of LPS injection on serum Igf1 and its liver mRNA. By contrast, meloxicam administration was unable to modify the inhibitory effect of LPS on Igfbp3. LPS injection also induced a decrease in GH receptor (Ghr) mRNA in the liver, and meloxicam attenuated this effect. In order to elucidate a direct action of the Ptgs2 inhibitor on the liver cells, the effect of LPS and/or meloxicam was studied in primary cultures of hepatocytes with non-parenchymal cells. LPS decreased Igf1 and Ghr but not Igfbp3 gene expression in liver cells in culture. Meloxicam administration attenuated the inhibitory effect of LPS on Igf1 mRNA, whereas it did not modify the decrease in Ghr mRNA after LPS. The effect of meloxicam on the LPS response does not seem to be mediated by changes in nitric oxide or tumour necrosis factor (Tnf) production, since meloxicam did not modify the stimulatory effect of LPS on nitric oxide or Tnfα gene expression both in vivo and in vitro. All these data suggest that LPS-induced Ptgs2 activation decreases Igf1 gene expression in liver cells.

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The Effect of Barbituric Acid Derivatives on Platelet Function in Vitro and in Vivo

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649080 ◽

1973 ◽

Vol 30 (02) ◽

pp. 315-326

Author(s):

J. Heinz Joist ◽

Jean-Pierre Cazenave ◽

J. Fraser Mustard

Keyword(s):

Platelet Aggregation ◽

Platelet Function ◽

Barbituric Acid ◽

Platelet Rich Plasma ◽

Inhibitory Effect ◽

Primary Response ◽

Sodium Pentobarbital ◽

Barbituric Acid Derivatives

SummarySodium pentobarbital (SPB) and three other barbituric acid derivatives were found to inhibit platelet function in vitro. SPB had no effect on the primary response to ADP of platelets in platelet-rich plasma (PRP) or washed platelets but inhibited secondary aggregation induced by ADP in human PRP. The drug inhibited both phases of aggregation induced by epinephrine. SPB suppressed aggregation and the release reaction induced by collagen or low concentrations of thrombin, and platelet adherence to collagen-coated glass tubes. The inhibition by SPB of platelet aggregation was readily reversible and isotopically labeled SPB did not become firmly bound to platelets. No inhibitory effect on platelet aggregation induced by ADP, collagen, or thrombin could be detected in PRP obtained from rabbits after induction of SPB-anesthesia.

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Inhibition of Human and Animal Platelet Adhesiveness to Glass Bead Columns by Adenosine, Dipyridamole, Chlorpromazine and Acetylsalicylic Acid

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648055 ◽

1976 ◽

Vol 36 (02) ◽

pp. 401-410 ◽

Cited By ~ 6

Author(s):

Buichi Fujttani ◽

Toshimichi Tsuboi ◽

Kazuko Takeno ◽

Kouichi Yoshida ◽

Masanao Shimizu

Keyword(s):

Guinea Pig ◽

Acetylsalicylic Acid ◽

Guinea Pigs ◽

Glass Bead ◽

Animal Species ◽

Inhibitory Effect ◽

Rabbit Platelet ◽

Platelet Adhesiveness

SummaryThe differences among human, rabbit and guinea-pig platelet adhesiveness as for inhibitions by adenosine, dipyridamole, chlorpromazine and acetylsalicylic acid are described, and the influence of measurement conditions on platelet adhesiveness is also reported. Platelet adhesiveness of human and animal species decreased with an increase of heparin concentrations and an increase of flow rate of blood passing through a glass bead column. Human and rabbit platelet adhesiveness was inhibited in vitro by adenosine, dipyridamole and chlorpromazine, but not by acetylsalicylic acid. On the other hand, guinea-pig platelet adhesiveness was inhibited by the four drugs including acetylsalicylic acid. In in vivo study, adenosine, dipyridamole and chlorpromazine inhibited platelet adhesiveness in rabbits and guinea-pigs. Acetylsalicylic acid showed the inhibitory effect in guinea-pigs, but not in rabbits.

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Phenolic Acids Exert Anticholinesterase and Cognition-Improving Effects

Current Alzheimer Research ◽

10.2174/1567205014666171128102557 ◽

2018 ◽

Vol 15 (6) ◽

pp. 531-543 ◽

Cited By ~ 4

Author(s):

Dominik Szwajgier ◽

Ewa Baranowska-Wojcik ◽

Kamila Borowiec

Keyword(s):

Phenolic Acids ◽

Ex Vivo ◽

Amyloid Β ◽

Inhibitory Effect ◽

In Vivo Studies ◽

Amyloid Β Peptide ◽

Beneficial Effects ◽

Aβ Fibrils

Numerous authors have provided evidence regarding the beneficial effects of phenolic acids and their derivatives against Alzheimer's disease (AD). In this review, the role of phenolic acids as inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) is discussed, including the structure-activity relationship. In addition, the inhibitory effect of phenolic acids on the formation of amyloid β-peptide (Aβ) fibrils is presented. We also cover the in vitro, ex vivo, and in vivo studies concerning the prevention and treatment of the cognitive enhancement.

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Stage-dependent effect of deferoxamine on growth of Plasmodium falciparum in vitro

Blood ◽

10.1182/blood.v76.6.1250.1250 ◽

1990 ◽

Vol 76 (6) ◽

pp. 1250-1255 ◽

Cited By ~ 36

Author(s):

S Whitehead ◽

TE Peto

Keyword(s):

Plasmodium Falciparum ◽

Growth Inhibition ◽

Antimalarial Activity ◽

Clinical Malaria ◽

Inhibitory Effect ◽

Parasite Development ◽

And Control ◽

Speed Of Onset

Abstract Deferoxamine (DF) has antimalarial activity that can be demonstrated in vitro and in vivo. This study is designed to examine the speed of onset and stage dependency of growth inhibition by DF and to determine whether its antimalarial activity is cytostatic or cytocidal. Growth inhibition was assessed by suppression of hypoxanthine incorporation and differences in morphologic appearance between treated and control parasites. Using synchronized in vitro cultures of Plasmodium falciparum, growth inhibition by DF was detected within a single parasite cycle. Ring and nonpigmented trophozoite stages were sensitive to the inhibitory effect of DF but cytostatic antimalarial activity was suggested by evidence of parasite recovery in later cycles. However, profound growth inhibition, with no evidence of subsequent recovery, occurred when pigmented trophozoites and early schizonts were exposed to DF. At this stage in parasite development, the activity of DF was cytocidal and furthermore, the critical period of exposure may be as short as 6 hours. These observations suggest that iron chelators may have a role in the treatment of clinical malaria.

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