scholarly journals Antiviral Activities of Compounds Isolated from Pinus densiflora (Pine Tree) against the Influenza A Virus

Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 711
Author(s):  
Thi Kim Quy Ha ◽  
Ba Wool Lee ◽  
Ngoc Hieu Nguyen ◽  
Hyo Moon Cho ◽  
Thamizhiniyan Venkatesan ◽  
...  

Pinus densiflora was screened in an ongoing project to discover anti-influenza candidates from natural products. An extensive phytochemical investigation provided 26 compounds, including two new megastigmane glycosides (1 and 2), 21 diterpenoids (3–23), and three flavonoids (24–26). The chemical structures were elucidated by a series of chemical reactions, including modified Mosher’s analysis and various spectroscopic measurements such as LC/MS and 1D- and 2D-NMR. The anti-influenza A activities of all isolates were screened by cytopathic effect (CPE) inhibition assays and neuraminidase (NA) inhibition assays. Ten candidates were selected, and detailed mechanistic studies were performed by various assays, such as Western blot, immunofluorescence, real-time PCR and flow cytometry. Compound 5 exerted its antiviral activity not by direct neutralizing virion surface proteins, such as HA, but by inhibiting the expression of viral mRNA. In contrast, compound 24 showed NA inhibitory activity in a noncompetitive manner with little effect on viral mRNA expression. Interestingly, both compounds 5 and 24 were shown to inhibit nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression in a dose-dependent manner. Taken together, these results provide not only the chemical profiling of P. densiflora but also anti-influenza A candidates.

2016 ◽  
Vol 54 (2) ◽  
pp. 214 ◽  
Author(s):  
Nguyen Manh Cuong ◽  
Pham Ngoc Khanh ◽  
Ho Viet Duc ◽  
Tran Thu Huong ◽  
Youn-Chui Kim ◽  
...  

Phytochemical investigation of the leaves and stems of Callistemon citrinus (Curtis) Skeels led to the isolation of 12 flavonoid and triterpenoid compounds,  including one new flavonoid, callistine A (1) and six known flavonoids 6,7- dimethyl-5,7-dihydroxy-4’-methoxy flavone (2), astragalin (3), quercetin (4), catechin (5), eucalyptin (6), and 8-demethyleucalyptin (7), along with 5 triterpenoids, 3-β-acetylmorolic acid (8), 3β-hydroxy-urs-11-en-13(28)-olide (9), betulinic acid (10), diospyrolide (11) and ursolic acid (12). Their chemical structures were determined from the spectroscopic evidences counting 1D- and 2D-NMR and HR-MS data. All the isolated compounds were examined for their anti-inflammatory activity against LPS-activated NO production in macrophage RAW264.7 cells. Among them, quercetin (4) and 3β-hydroxy-urs-11-en-13(28)-olide (9) showed potential inhibition activity in nitric oxide (NO)  production in RAW264.7 cells exposed to LPS.


1998 ◽  
Vol 274 (1) ◽  
pp. C245-C252 ◽  
Author(s):  
Junsuke Igarashi ◽  
Masashi Nishida ◽  
Shiro Hoshida ◽  
Nobushige Yamashita ◽  
Hiroaki Kosaka ◽  
...  

The effects of nitric oxide (NO) produced by cardiac inducible NO synthase (iNOS) on myocardial injury after oxidative stress were examined. Interleukin-1β induced cultured rat neonatal cardiac myocytes to express iNOS. After induction of iNOS,l-arginine enhanced NO production in a concentration-dependent manner. Glutathione peroxidase (GPX) activity in myocytes was attenuated by elevated iNOS activity and by an NO donor, S-nitroso- N-acetyl-penicillamine (SNAP). Although NO production by iNOS did not induce myocardial injury, NO augmented release of lactate dehydrogenase from myocyte cultures after addition of H2O2(0.1 mM, 1 h). Inhibition of iNOS with Nω-nitro-l-arginine methyl ester ameliorated the effects of NO-enhancing treatments on myocardial injury and GPX activity. SNAP augmented the myocardial injury induced by H2O2. Inhibition of GPX activity with antisense oligodeoxyribonucleotide for GPX mRNA increased myocardial injury by H2O2. Results suggest that the induction of cardiac iNOS promotes myocardial injury due to oxidative stress via inactivation of the intrinsic antioxidant enzyme, GPX.


Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2631 ◽  
Author(s):  
Zeyuan Wang ◽  
Jianfeng Cai ◽  
Qing Fu ◽  
Lingping Cheng ◽  
Lehao Wu ◽  
...  

Fifteen unreported compounds in Anemarrhena asphodeloides, iriflophene (3), hostaplantagineoside C (7), tuberoside G (8), spicatoside B (9), platycodin D (14), platycoside A (15), platycodin D2 (16), polygalacin D2 (17), platycodin D3 (18), isovitexin (20), vitexin (21), 3,4-dihydroxyallylbenzene-3-O-α-l-rhamnopyranosyl(1→6)-β-d-glucopyranoside (22), iryptophan (24), adenosine (25), α-d-Glucose monoallyl ether (26), together with eleven known compounds (1, 2, 4–6, 10–13, 19 and 23), were isolated from the rhizomes of Anemarrhena asphodeloides. The chemical structures of these compounds were characterized using HRMS and NMR. The anti-inflammatory activities of the compounds were evaluated by investigating their ability to inhibit LPS-induced NO production in N9 microglial cells. Timosaponin BIII (TBIII) and trans-hinokiresinol (t-HL) exhibited significant inhibitory effects on the NO production in a dose-dependent manner with IC50 values of 11.91 and 39.08 μM, respectively. Immunoblotting demonstrated that TBIII and t-HL suppressed NO production by inhibiting the expressions of iNOS in LPS-stimulated N9 microglial cells. Further results revealed that pretreatment of N9 microglial cells with TBIII and t-HL attenuated the LPS-induced expression tumor necrosis factor (TNF)-α and interleukin-6 (IL-6) at mRNAs and protein levels. Moreover, the activation of nuclear factor-κB (NF-κB) and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways were inhibited by TBIII and t-HL, respectively. Our findings indicate that the therapeutic implication of TBIII and t-HL for neurogenerative disease associated with neuroinflammation.


1995 ◽  
Vol 269 (2) ◽  
pp. C519-C523 ◽  
Author(s):  
J. M. Li ◽  
R. A. Fenton ◽  
B. S. Cutler ◽  
J. G. Dobson

Adenosine per se is a potent vasodilator of vascular smooth muscle. Endothelial cells modulate vascular tone via the release of nitric oxide (NO), which also elicits vasodilation. This study was undertaken to determine whether adenosine could directly stimulate endothelial cells to enhance NO production, which could subsequently reduce vascular tone. NO production was evaluated in porcine carotid artery endothelial cells (PCAEC) and human saphenous vein endothelial cells (HSVEC) seeded on multiwell plates, grown to confluence, and treated with adenosine for 1 h. The bathing medium was collected, and the NO production was determined as reflected by the formation of NO2- and NO3-. NO production by PCAEC was significantly increased by adenosine in a dose-dependent manner, whereas there was only an insignificant tendency for an increase by HSVEC. The addition of the NO synthase competitive inhibitor, NG-monomethyl-L-arginine (NMMA), or the adenosine receptor antagonist, theophylline, prevented the increase in NO production by adenosine. The results suggest that adenosine stimulates, by a receptor-mediated mechanism, the production of NO by arterial, but not by venous, endothelial cells.


2001 ◽  
Vol 281 (6) ◽  
pp. C1819-C1824 ◽  
Author(s):  
Yao Song ◽  
Jay L. Zweier ◽  
Yong Xia

Recent studies showed that heat shock protein 90 (HSP90) enhances nitric oxide (NO) synthesis from endothelial and neuronal NO synthase (eNOS and nNOS, respectively). However, these findings were based on indirect NO measurements. Moreover, although our previous studies showed that the action of HSP90 involves increased Ca2+/calmodulin (Ca2+/CaM) binding, quantitative measurements of the effect of HSP90 on CaM binding to nNOS have been lacking. With electron paramagnetic resonance spectroscopy, we directly measured NO signals from purified nNOS. HSP90 augmented NO formation from nNOS in a dose-dependent manner. Tryptophan fluorescence-quenching measurements revealed that HSP90 markedly reduced the K d of CaM to nNOS (0.5 ± 0.1 nM vs. 9.4 ± 1.8 nM in the presence and absence of HSP90, P < 0.01). Ca2+ ionophore triggered strong NO production from nNOS-transfected cells, and this was significantly reduced by the HSP90 inhibitor geldanamycin. Thus these studies provide direct evidence demonstrating that HSP90 enhances nNOS catalytic function in vitro and in intact cells. The effect of HSP90 is mediated by the enhancement of CaM binding to nNOS.


Molecules ◽  
2020 ◽  
Vol 25 (20) ◽  
pp. 4762
Author(s):  
Jenny Chun-Ling Kuo ◽  
Li-Jie Zhang ◽  
Hung-Tse Huang ◽  
Chia-Ching Liaw ◽  
Zhi-Hu Lin ◽  
...  

Eleven compounds, including nine known flavonoid glycosides (1–4, 6–8, and 10–11), one isoflavone glycoside (5), and a glansreginic acid (9), were isolated from the 80% ethanol extract of commercial Astragali Complanati Semen (ACS). All chemical structures were determined by spectroscopic analyses, including 1D and 2D NMR. Compounds 2, 4, 5, 6, 9, and 10 were isolated and identified from the title plant for the first time. Biological evaluation revealed that all the isolates showed promising anti-NO production, and 1, 2, 3, and 8 were more potent in antioxidant activity than vitamin E. The major peaks in the UPLC and HPLC profiles identified their chemical structures by comparing their retention time and UV spectra with those of the reference substances. Furthermore, nine of the eleven samples collected from North, Middle, and South regions of Taiwan possessed similar HPLC fingerprints and were identified as Astragali Complanati Semen, whereas the other two samples from southern Taiwan would be the adulterants due to the different fingerprinting patterns. In addition, an HPLC-UV method was employed to determine the content of target compound complanatuside (11) with good linear regression (R2 = 0.9998) for ACS in the Taiwanese market. Of the isolates, flavonol glycosides 1 and 3 were the major peaks in HPLC/UPLC, and showed more potent antioxidant and anti-NO production activities than that of 11, revealing that these compounds can be the available agents for the quality control of ACS.


2007 ◽  
Vol 75 (9) ◽  
pp. 4305-4315 ◽  
Author(s):  
Rupesh Chaturvedi ◽  
Mohammad Asim ◽  
Nuruddeen D. Lewis ◽  
Holly M. Scott Algood ◽  
Timothy L. Cover ◽  
...  

ABSTRACT Helicobacter pylori infection of the stomach causes an active immune response that includes stimulation of inducible nitric oxide (NO) synthase (iNOS) expression. Although NO can kill H. pylori, the bacterium persists indefinitely, suggesting that NO production is inadequate. We determined if the NO derived from iNOS in macrophages was dependent on the availability of its substrate, l-arginine (l-Arg). Production of NO by H. pylori-stimulated RAW 264.7 cells was dependent on the l-Arg concentration in the culture medium, and the 50% effective dose for l-Arg was 220 μM, which is above reported plasma l-Arg levels. While iNOS mRNA induction was l-Arg independent, iNOS protein increased in an l-Arg-dependent manner that did not involve changes in iNOS protein degradation. l-Lysine, an inhibitor of l-Arg uptake, attenuated H. pylori-stimulated iNOS protein expression, translation, NO levels, and killing of H. pylori. While l-Arg starvation suppressed global protein translation, at concentrations of l-Arg at which iNOS protein was only minimally expressed in response to H. pylori, global translation was fully restored and eukaryotic translation initiation factor α was dephosphorylated. H. pylori lacking the gene rocF, which codes for a bacterial arginase, induced higher levels of NO production by increasing iNOS protein levels. When murine gastric macrophages were activated with H. pylori, supraphysiologic levels of l-Arg were required to permit iNOS protein expression and NO production. These findings indicate that l-Arg is rate limiting for iNOS translation and suggest that the levels of l-Arg that occur in vivo do not permit sufficient NO generation by the host to kill H. pylori.


2018 ◽  
Vol 46 (06) ◽  
pp. 1281-1296 ◽  
Author(s):  
Sang Yun Han ◽  
Young-Su Yi ◽  
Seong-Gu Jeong ◽  
Yo Han Hong ◽  
Kang Jun Choi ◽  
...  

Lilium bulbs have long been used as Chinese traditional medicines to alleviate the symptoms of various human inflammatory diseases. However, mechanisms of Lilium bulb-mediated anti-inflammatory activity and the bioactive components in Lilium bulbs remain unknown. In the present study, the anti-inflammatory activity of Lilium bulbs and the underlying mechanism of action were investigated in macrophages using Lilium bulb ethanol extracts (Lb-EE). In a dose-dependent manner, Lb-EE inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and bone marrow-derived macrophages (BMDMs) without causing significant cytotoxicity. Lb-EE also down-regulated mRNA expression of inflammatory genes in LPS-stimulated RAW264.7 cells, which included inducuble nitric oxide synthase (iNOS), cyclooxygenase-2 (COX2), and tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]). Furthermore, Lb-EE markedly restored LPS-induced morphological changes in RAW264.7 cells to a normal morphology. HPLC analysis identified quercetin, luteolin, and kaempferol as bioactive components contained in Lb-EE. Mechanistic studies in LPS-stimulated RAW264.7 cells revealed that Lb-EE suppressed MyD88- and TRIF-induced NF-[Formula: see text]B transcriptional activation and the nuclear translocation of NF-[Formula: see text]B transcription factors. Moreover, Lb-EE inhibited IKK[Formula: see text]/[Formula: see text]-induced activation of the NF-[Formula: see text]B signaling pathway and IKK inhibition significantly reduced NO production in LPS-stimulated RAW264.7 cells. Taken together, these results suggest that Lb-EE plays an anti-inflammatory role by targeting IKK[Formula: see text]/[Formula: see text]-mediated activation of the NF-[Formula: see text]B signaling pathway during macrophage-mediated inflammatory responses.


2017 ◽  
Vol 12 (1) ◽  
pp. 1934578X1701200
Author(s):  
Phan Van Kiem ◽  
Le Canh Viet Cuong ◽  
Do Thi Trang ◽  
Nguyen Xuan Nhiem ◽  
Hoang Le Tuan Anh ◽  
...  

Using various chromatographic methods, two new alkaloids, antidesoic acids A (1) and B (2) along with fourteen known compounds (3-16) were isolated from the leaves of Antidesma ghaesembilla Gaertn. Their chemical structures were elucidated by physical and chemical methods. All the isolated compounds were evaluated for their inhibitory activity on LPS-stimulated nitric oxide (NO) production in BV2 cells and RAW 264.7 macrophages. Bisflavone 8 significantly inhibited LPS-stimulated NO production in BV2 cells and RAW 264.7 macrophages with IC50 values of 5.4 and 8.0 μM, respectively. Compounds 1–3, 7, 10, 12, 14, and 16 showed moderate inhibitory activities with IC50 values ranging from 11.7 to 77.4 μM.


2019 ◽  
Vol 12 (564) ◽  
pp. eaar5514 ◽  
Author(s):  
Mariko Takahashi ◽  
Kumi Izawa ◽  
Makoto Urai ◽  
Yoshinori Yamanishi ◽  
Akie Maehara ◽  
...  

Zymosan is a glucan that is a component of the yeast cell wall. Here, we determined the mechanisms underlying the zymosan-induced accumulation of neutrophils in mice. Loss of the receptor CD300b reduced the number of neutrophils recruited to dorsal air pouches in response to zymosan, but not in response to lipopolysaccharide (LPS), a bacterial membrane component recognized by Toll-like receptor 4 (TLR4). An inhibitor of nitric oxide (NO) synthesis reduced the number of neutrophils in the zymosan-treated air pouches of wild-type mice to an amount comparable to that inCD300b−/−mice. Treatment with clodronate liposomes decreased the number of NO-producing, CD300b+inflammatory dendritic cells (DCs) in wild-type mice, thus decreasing NO production and neutrophil recruitment. Similarly, CD300b deficiency decreased the NO-dependent recruitment of neutrophils to zymosan-treated joint cavities, thus ameliorating subsequent arthritis. We identified phytosphingosine, a lipid component of zymosan, as a potential ligand of CD300b. Phytosphingosine stimulated NO production in inflammatory DCs and promoted neutrophil recruitment in a CD300b-dependent manner. Together, these results suggest that the phytosphingosine-CD300b interaction promotes zymosan-dependent neutrophil accumulation by inducing NO production by inflammatory DCs and that CD300b may contribute to antifungal immunity.


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