Inhibition Of Nitric Oxide Production Research Articles

Echinacea Polyphenols Inhibit NLRP3-Dependent Pyroptosis, Apoptosis, and Necroptosis via Suppressing NO Production during Lipopolysaccharide-Induced Acute Lung Injury.

PANoptosis is an intricate programmed death pathway that involves the interaction between pyroptosis, apoptosis, and necroptosis. We systematically explored the protective effect of Echinacea polyphenols (EPP) against the lipopolysaccharide (LPS)-induced acute lung injury (ALI) and the underlying mechanisms both in vitro and in vivo. We noted that EPP pretreatment could significantly alleviate LPS-induced lung tissue injury and pulmonary edema. EPP inhibited the PANoptosis by regulating the expression of nucleotide-binding oligomerization domain-like receptor protein 3 inflammasome, gasdermin D, caspase-8, caspase-3, and mixed lineage kinase domain-like protein. Meanwhile, a comparative study of EPP and inducible nitric oxide synthase inhibitor S-methylisothiourea sulfate indicated that EPP may play a preprotective role in inhibiting PANoptosis via reducing the activity of inducible nitric oxide synthase and the production of nitric oxide (NO) during ALI. Our results clearly indicated that PANoptosis existed in LPS-induced ALI, and EPP pretreatment could provide obvious protective effects to LPS-induced ALI by inhibiting PANoptosis, which may be related to NO production.

Guided Analysis of Selected Ethnobotanical Acanthaceous Plants for Anti-Inflammatory Properties

Acanthaceous plants have emerged as important therapeutic plants on a global scale, producing biologically active chemical compounds with larvicidal, antimicrobial, and cytotoxic properties. In traditional Thai medicine, the crude extracts of these plants, including Clinacanthus nutans, Justicia gendarussa, and Rhinacanthus nasutus, have been used to detoxify bug bites and some skin illnesses caused by fungus and viruses. This study argued for investigating acanthaceous plant extracts for alternate advantages such as anti-inflammation. The presence of anti-inflammatory components in extracts was examined using HPLC in order to evaluate their potential. Lupeol, a prospective anti-inflammatory triterpene found in medicinal plants, was employed as a chemical marker. The anti-inflammatory activities of extracts containing the active chemical were studied utilizing protein denaturation and inhibition of nitric oxide production in RAW 264.7 cells stimulated with LPS. Also, the extract of combined active plants was assessed. Lupeol was detected in the tested extracts in quantities ranging from 0.25 to 1.22% w/w. It was found in the highest concentration in the extract of Clinacanthus nutans and in the lowest concentration in the extract of Justicia gendarussa. All extracts of plants containing the active ingredient exhibited anti-inflammatory effects. Their IC50 values ranged between 0.87 and 29.28 mg/mL. The extract made from a combination of plants that contained lupeol demonstrated the most potent anti-inflammatory effect, with a 0.6-fold difference when compared to diclofenac. This research implied that investigating acanthaceous plant extracts containing this active agent might be more beneficial in the design of herbal recipes with anti-inflammatory characteristics.

Rugulopteryx-Derived Spatane, Secospatane, Prenylcubebane and Prenylkelsoane Diterpenoids as Inhibitors of Nitric Oxide Production

This study aimed to evaluate the anti-inflammatory potential of the different classes of diterpenoids produced by algae of the genus Rugulopteryx. First, sixteen diterpenoids (1-16), including spatane, secospatane, prenylcubebane, and prenylkelsoane metabolites, were isolated from the extract of the alga Rugulopteryx okamurae collected at the southwestern Spanish coasts. Eight of the isolated diterpenoids are new compounds whose structures were determined by spectroscopic means: the spatanes okaspatols A-D (1-4); the secospatane rugukamural D (8); the prenylcubebanes okacubols A (13) and B (14); and okamurol A (16), which exhibits an unusual diterpenoid skeleton featuring a kelsoane-type tricyclic nucleus. Second, anti-inflammatory assays were performed on microglial cells Bv.2 and macrophage cells RAW 264.7. Compounds 1, 3, 6, 12, and 16 caused significant inhibition of the NO overproduction induced by LPS in Bv.2 cells, and compounds 3, 5, 12, 14, and 16 significantly decreased levels of NO in LPS-stimulated RAW 264.7 cells. The most active compound was okaspatol C (3), which completely suppressed the effects of LPS stimulation, both in Bv.2 and in RAW 264.7 cells.

Aconicumines A–D, an advanced class of norditerpenoid alkaloids with an unprecedented N,O-diacetal motif from Aconitum taipeicum Hand.-Mazz., exhibit anti-inflammatory properties in vitro

Aconicumines A–D, an advanced class of norditerpenoid alkaloids, and seven known alkaloids, were isolated from Aconitum taipaicum Hand.-Mazz. (Ranunculaceae). The structures of the previously undescribed compounds, including their absolute configurations, were fully elucidated based on spectroscopic and single-crystal X-ray diffraction data analysis. Aconicumines A–D exhibit interesting cage-like structure, characterised by an unprecedented N,O-diacetal moiety (C6–O–C19–N–C17–O–C7) that has not been previously observed in diterpenoid alkaloids. Possible biosynthetic pathways for aconicumines A–D were proposed. Aconitine, hypaconitine, and aconicumine A showed significant inhibition of nitric oxide production in RAW 264.7 macrophages induced by lipopolysaccharide with IC50 values ranging from 4.1 to 19.7 μM compared to positive control (dexamethasone, IC50 = 12.5 μM). Furthermore, the primary structure–activity relationships for aconicumines A–D were also represented.

Inhibition of NO Production in LPS-Stimulated Primary Rat Glial Cells by Gnidilatimonoein and Extract of Daphne mucronata.

In the CNS, glial cells are involved in neuroinflammation and neuropathic pain. The glial cells are activated by a variety of pathological conditions and release pro-inflammatory mediators, including nitric oxide (NO). Overexpression of iNOS (inducible nitric oxide synthase) and extra NO is detrimental to neurophysiology and neuronal viability. This study aimed to examine the effect of Gnidilatimonein isolated from D. mucronata and its leaves extract (as natural phytochemicals) on NO production in the LPS-induced primary glial cells. A preparative HPLC method was used to isolate gnidilatimonoein from leaves ethanolic extract. Various doses of Gnidilatimonoein, the ethanolic extract were applied to primary glial cells inflamed by lipopolysaccharide. A Colorimetric test, an MTT assay, and a RT-PCR analysis were then performed to analyze and compare NO production, cell viability, and iNOS expression. Gnidilatimonoein treatment of pretreated primary glial cells significantly inhibited iNOS expression and decreased NO synthesis. Plant extracts also reduced NO production in inflamed microglial and glial at 0.1-3 mg.mL-1. At these concentrations, none of these compounds exerted a cytotoxic effect, suggesting that their anti-inflammatory effects were not due to the death of cells. This study indicates that D. mucronata and its active compound, Gnidilatimonoein, could have restrained effects on the expression of iNOS on the induced glial cells; however, further investigation is warranted.

Synthesis and Evaluation of DHMEQ Derivatives with Tertiary Hydroxyl Group Instead of Secondary Hydroxyl Group.

Newly synthesized dehydroxymethyl epoxyquinomycin (DHMEQ) derivatives 6-9, which contain a tertiary hydroxyl group instead of the original secondary hydroxyl group, showed improved solubility in alcohol while maintaining their inhibitory activity against nitric oxide (NO) production, which is used as an indicator of nuclear factor-kappa B (NF-κB) inhibitory activity. We also synthesized a derivative 5 having a cyclopropane ring and a tertiary hydroxyl group and examined its inhibitory activity against NO production. Although it reacted with a nucleophile in a flask, it did not inhibit NO production. The change from a secondary hydroxyl group to a tertiary hydroxyl group contributed to improve the solubility of the compounds while retaining NO inhibitory activity, but had no effect on improving the activity of the cyclopropane form. Compounds in which the secondary hydroxyl group of DHMEQ was converted to a tertiary hydroxyl group would be excellent NF-κB inhibitor candidates because their solubility is improved without decreasing NO inhibitory activity.

Porphyromonas gingivalis에 대한 레몬그라스 오일 및 레몬그라스 에탄올 추출물의 항균 활성

Objectives: This study analyzed the antibacterial effects of LGEE and LGEO against P. gingivalis, thus the potential utility was evaluated as the functional materials for oral healthcare. Methods: Nitric oxide (NO) assay and cytotoxicity were analyzed by the Griess reaction and WST-1 assay, respectively. Antibacterial activity against P. gingivalis was evaluated by disk diffusion method and proliferation inhibition assay. Results: LGEO and LGEE significantly inhibited NO production as well as the proliferation of P. gingivalis in a dose dependent manner. Conclusions: LGEO and LGEE inhibited potently NO production and P. gingivalis proliferation, which means they could be used as a numerous lines of functional materials for improving oral health.

New Triterpenoids and Anti-Inflammatory Constituents from Glinus oppositifolius.

Three new triterpenoids-spergulagenin B (1), spergulagenin C (2), and spergulagenin D (3)-were isolated from the aerial part of Glinus oppositifolius, along with 17 known compounds (4-20). The structures of these new compounds were identified by spectroscopic and MS analyses. Compounds 3, 5, 19, and 20 were evaluated for inhibition of nitric oxide production in LPS-stimulated RAW 264.7 cells with IC50 values of 17.03, 18.21, 16.30, and 12.64 μM, respectively. Compounds 3, 5, and 20 exhibited inhibitory effects on LPS-induced nitric oxide production in RAW 264.7 cells with IC50 values of 18.35 ± 1.34, 17.56 ± 1.41, and 14.27 ± 1.29 μM, respectively.

New Isopropyl Chromone and Flavanone Glucoside Compounds from the Leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry and Their Inhibition of Nitric Oxide Production.

A new isopropyl chromone (1) and a new flavanone glucoside (2) together with eleven known compounds (3-13) were isolated from the leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry. Their structures were elucidated as 5,7-dihydroxy-2-isopropyl-6,8-dimethyl-4H-chromen-4-one (1), 5,7-dihydroxyflavanone 7-O-β-D-(6''-O-galloylglucopyranoside) (2), strobopinin (3), demethoxymatteucinol (4), pinocembrin-7-O-β-D-glucopyranoside (5), (2S)-hydroxynaringenin-7-O-β-D-glucopyranoside (6), afzelin (7), quercetin (8), kaplanin (9), endoperoxide G3 (10), grasshopper (11), vomifoliol (12), litseagermacrane (13) by the analysis of HR-ESI-MS, NMR, and CD spectral data. Compounds 1, 2, 5, 6 and 10 inhibited NO production on LPS-activated RAW264.7 cells with IC50 values of 12.28±1.15, 8.52±1.62, 7.68±0.87, 9.67±0.57, and 6.69±0.34 μM, respectively, while the IC50 values of the other compounds ranging from 33.38±0.78 to 86.51±2.98 μM, compared to that of the positive control, NG -monomethyl-L-arginine acetate (L-NMMA) with an IC50 value of 32.50±1.00 μM.

Turmeric Herb Extract-Incorporated Biopolymer Dressings with Beneficial Antibacterial, Antioxidant and Anti-Inflammatory Properties for Wound Healing

Bacterial infection and inflammation caused by excess oxidative stress are serious challenges in chronic wound healing. The aim of this work is to investigate a wound dressing based on natural- and biowaste-derived biopolymers loaded with an herb extract that demonstrates antibacterial, antioxidant, and anti-inflammatory activities without using additional synthetic drugs. Turmeric extract-loaded carboxymethyl cellulose/silk sericin dressings were produced by esterification crosslinking with citric acid followed by freeze-drying to achieve an interconnected porous structure, sufficient mechanical properties, and hydrogel formation in situ in contact with an aqueous solution. The dressings exhibited inhibitory effects on the growth of bacterial strains that were related to the controlled release of the turmeric extract. The dressings provided antioxidant activity as a result of the radical scavenging effect on DPPH, ABTS, and FRAP radicals. To confirm their anti-inflammatory effects, the inhibition of nitric oxide production in activated RAW 264.7 macrophages was investigated. The findings suggested that the dressings could be a potential candidate for wound healing.

Phytochemicals, Cytotoxicity, Inhibitory Effect on Nitric Oxide Production and Alpha-Glucosidase Activity, and DPPH Scavenging Activity of Leaf Extract from Gymnema inodorum (Lour.) Decne

Investigation of phytochemicals, cyto-toxicity, inhibitory effect on nitric oxide (NO) production and α-glucosidase activity, and DPPH scavenging activity of leaf extract from Gymnema inodorum (Lour.) Decne (LEGI) revealed that GC-MS analysis demonstrated the presence of 83 phytochemicals with 5 main compounds i.e. Phytol (18.14 %), n-Hexadecanoic acid (12.45 %), 9,12-Octadecadienoic acid (Z,Z)-(3.92 %), 9,12,15-Octadecatrienoic acid, (Z,Z,Z)-(10.39 %) and Betulin (8.56 %), and 78 trace compounds in LEGI. MTT assay to investigate cytotoxicity showed that LEGI exhibited low cytotoxicity to the RAW 264.7 macrophages with IC50 of 128.77±2.82 µg/mL. Treatment with the LEGI significantly inhibited nitric oxide (NO) production, an inflammatory mediator, in the LPS-stimulated RAW 264.7 cells. At the concentration of 50 mg/mL, LEGI inhibited NO production by 16.73±1.52 % which was less than Diclofenac did (27.07±1.81 %). The α-glucosidase inhibitory activity to determine the antidiabetic activity showed that LEGI exhibited the inhibition on α-glucosidase activity with IC50 of 0.34 mg/mL, which was less potent than Acarbose (IC50 of 0.20 mg/mL). Assay of 2,2-diphenyl-2-picrylhydrazyl- hydrate (DPPH) radical scavenging to examine antioxidant activity revealed that LEGI demonstrated less potent DPPH scavenging activity compared to Butylated hydroxytoluene, BHT with IC50 of 0.43 vs 0.36 mg/mL, respectively. These results indicate that the leaf extract from G. inodorum possesses anti-inflamatory, antidiabetic and antioxidant activities that can be developed and used as natural agents for the tréamatent of diseases related to these activities. HIGHLIGHTS Using GC-MS analysis, there are 83 phytochemicals identified with 5 main compounds i.e. Phytol, n-Hexadecanoic acid, 9,12-Octadecadienoic acid (Z,Z)-, 9,12,15-Octadecatrienoic acid, (Z,Z,Z)- and Betulin, and 78 trace compounds in the ethanol leaf extract from Gymnema inodorum, and Phytol is the most predominant compound The extract can inhibit nitric oxide (NO) production, indicating its anti-inflammatory property The extract displays the inhibitory effect on α-Glucosidase activity, suggesting that the extract can be applied for antidiabetic management The extract possesses antioxidant property as evidenced by scavenging DPPH free radicals The extract shows low cytotoxicity to RAW 264.7 macrophages with IC50 of 128.77±2.82 µg/ml, by MTT assay GRAPHICAL ABSTRACT

Anti-inflammatory Action of BT75, a Novel RARα Agonist, in Cultured Microglia and in an Experimental Mouse Model of Alzheimer's Disease.

BT75, a boron-containing retinoid, is a novel retinoic acid receptor (RAR)α agonist synthesized by our group. Previous studies indicated that activation of retinoic acid (RA) signaling may attenuate progression of Alzheimer's disease (AD). Presently, we aimed to examine the anti-inflammatory effect of BT75 and explore the possible mechanism using cultured cells and an AD mouse model. Pretreatment with BT75 (1-25 µM) suppressed the release of nitric oxide (NO) and IL-1β in the culture medium of mouse microglial SIM-A9 cells activated by LPS. BMS195614, an RARα antagonist, partially blocked the inhibition of NO production by BT75. Moreover, BT75 attenuated phospho-Akt and phospho-NF-κB p65 expression augmented by LPS. In addition, BT75 elevated arginase 1, IL-10, and CD206, and inhibited inducible nitric oxide synthase (iNOS) and IL-6 formation in LPS-treated SIM-A9 cells, suggesting the promotion of M1-M2 microglial phenotypic polarization. C57BL/6 mice were injected intracerebroventricularly (icv) with streptozotocin (STZ) (3mg/kg) to provide an AD-like mouse model. BT75 (5mg/kg) or the vehicle was intraperitoneally (ip) injected to icv-STZ mice once a day for 3 weeks. Immunohistochemical analyses indicated that GFAP-positive cells and rod or amoeboid-like Iba1-positive cells, which increased in the hippocampal fimbria of icv-STZ mice, were reduced by BT75 treatment. Western blot results showed that BT75 decreased levels of neuronal nitric oxide synthase (nNOS), GFAP, and phosphorylated Tau, and increased levels of synaptophysin in the hippocampus of icv-STZ mice. BT75 may attenuate neuroinflammation by affecting the Akt/NF-κB pathway and microglial M1-M2 polarization in LPS-stimulated SIM-A9 cells. BT75 also reduced AD-like pathology including glial activation in the icv-STZ mice. Thus, BT75 may be a promising anti-inflammatory and neuroprotective agent worthy of further AD studies.

A New Lignan (Polonilignan) and Inhibitors of Nitric Oxide Production from Penicillium polonicum, an Endophytic Fungi of Piper nigrum.

Inhibiting nitric oxide (NO) or its production is found to be of therapeutic benefit. To discover natural small molecule inhibitors of NO production, a bioassay- and LC/MS-guided chemical investigation was done on the metabolites of endophytic fungus isolated from fresh Piper nigrum fruits. The isolated pure strain was identified as Penicillium polonicum by 16S rDNA sequence comparison. The culture broth extract of P. polonicum (EEPP) exhibited a significant reduction of NO production (Griess method) in LPS-stimulated RAW 264.7 cells (P<0.0001). To understand the chemical constituents of bioactive EEPP, column chromatography and p-TLC studies were carried out, which yielded eight pure compounds. They were characterised as botryosphaeridione (1), 3-(3,5-di-tert-butyl-4-hydroxy)phenylpropionic acid (2), variabilone (3), 2,4-di-tert-butylphenol (4), indole-3-carboxylic acid (5), tyrosol (6), ethyl ferulate (7) and a new lignan (8) based on the spectral analysis. The structure elucidation of the new lignan, named polonilignan (8), was based on HR-MS, 1 H- & 13 C-NMR, H-H COSY, HSQC and HMBC spectra. Compounds 2, 4, 5 and 6 showed a significant decrease (P<0.0001) in the production of NO in LPS-induced RAW 264.7 cells. Tyrosol (6) and indole-3-carboxylic acid (5) controlled nitrite release with IC50 values of 22.84 and 55.01 μM, respectively. This is the first report of (i) P. polonicum as an endophytic fungus of pepper fruits, (ii) isolation of compounds 1-8 except 6 from P. polonicum culture broth extract and (iii) NO inhibition effect of 2, 4, 5 and 6.

Bradykinin promotes murine melanoma cell migration and invasion through endogenous production of superoxide and nitric oxide

Spatial confinement and temporal regulation of signaling by nitric oxide (NO) and reactive oxygen species (ROS) occurs in cancer cells. Signaling mediated by NO and ROS was investigated in two sub clones of the murine melanoma B16F10-Nex2 cell line, Nex10C and Nex8H treated or not with bradykinin (BK). The sub clone Nex10C, similar to primary site cells, has a low capacity for colonizing the lungs, whereas the sub clone Nex8H, similar to metastatic cells, corresponds to a highly invasive melanoma. BK-treated Nex10C cells exhibited a transient increase in NO and an inhibition in basal O2− levels. Inhibition of endogenous NO production by l-NAME resulted in detectable levels of O2−. l-NAME promoted Rac1 activation and enhanced Rac1–PI3K association. l-NAME in the absence of BK resulted in Nex10C cell migration and invasion, suggesting that NO is a negative regulator of O2− mediated cell migration and cell invasion. BK-treated Nex8H cells sustained endogenous NO production through the activation of NOS3. NO activated Rac1 and promoted Rac1–PI3K association. NO stimulated cell migration and cell invasion through a signaling axis involving Ras, Rac1 and PI3K. In conclusion, a role for O2− and NO as positive regulators of Rac1–PI3K signaling associated with cell migration and cell invasion is proposed respectively for Nex10C and Nex8H murine melanoma cells.

Phytochemical Characterization and In Vitro Anti-Inflammatory Evaluation in RAW 264.7 Cells of Jatropha cordata Bark Extracts.

The inflammatory process, although beneficial, can produce tissue damage and systemic damage when uncontrolled. Effective therapeutic alternatives with little or no side effects are of great therapeutic interest. This study aimed to determine the phytochemical composition of bark extracts from J. cordata, an endemic plant from México, and evaluate their in vitro anti-inflammatory activity. Hexane, ethyl acetate, and methanol extracts were characterized by qualitative phytochemical tests, and their bioactive groups were identified by 1H NMR and gas chromatography coupled to mass spectrometry (GC-MS). The extract's anti-inflammatory activity was evaluated as nitric oxide (NO) production and their cytotoxicity by an MTS cell proliferation assay in lipopolysaccharide (LPS)-activated RAW 264.7 cells at concentrations of 1-100 μg/mL. The hexane extract contained fatty acids, fatty esters, phytosterols, alkanes, vitamin E, and terpenoids; the ethyl acetate extract showed fatty acids, fatty esters, aromatic aldehyde, phytosterols, vitamin E, and terpenoids, while the methanolic extract showed fatty esters, fatty acid, aromatics aldehydes, and alcohol. The ethyl acetate extract showed the highest inhibition of NO production, followed by the methanolic extract and the hexane extract, without affecting the viability of RAW 264.7 macrophage cells. The results suggest that J. cordata extracts are a potential source of bioactive compounds with anti-inflammatory potential.

Phytochemical Compositions, Nutritional Contents, Cytotoxicity and Anti-Inflammatory Activity of Different Extracts from Spirogyra neglecta (Hassall) Kützing

Spirogyra neglecta (Hassall) Kützing is an edible freshwater macroalga. It is available and consumed as local food in Thailand, especially in the northern and northeastern parts. To ascertain its good benefit for health and safe for consumption, this study was, therefore carried out to determine the phytochemical compositions, nutritional contents, cytotoxicity, and anti-inflammatory activity of the different extracts from S. neglecta. The extracts were prepared by using different solvents, such as propylene glycol, methanol, and ethanol solutions. GC-MS analysis revealed the presence of 30, 39 and 36 phytochemical compounds in propylene glycol, methanol, and ethanol extracts, respectively. Phytol, which has been reported to have anti-inflammatory activity, was one of the predominant compositions in the extracts. The extracts contained high nutritional contents of protein, lipid, fiber, ash, moisture, and carbohydrate up to 21.68 ± 4.52, 3.53 ± 0.23, 14.77 ± 0.89, 10.73 ± 0.47, 9.79 ± 0.11 and 47.36 ± 3.89 %, respectively. The highest total protein was found in propylene glycol extract. The highest total lipid was in ethanol extract. Meanwhile, the highest fiber, ash and total carbohydrate were in methanol extract. In addition, all the extracts possess relatively low cytotoxicity, with IC50 values greater than 1,000 µg/mL. The extracts 1,000 µg/mL exhibited anti-inflammatory activity via inhibition Nitric oxide (NO) production by 29.87 ± 1.56 to 55.17 ± 1.91 %. The propylene glycol extracts from S. neglecta showed the highest inhibitory activity on NO production compared to others. The overall results indicating the propylene glycol is the solvent that produces the best extraction performance. The extracts from S. neglecta exhibit anti-inflammatory activity by inhibiting NO production. The phytochemical compositions are partly responsible for anti-inflammatory activity of the extracts. The high nutritional contents complement relatively low toxic. Thus, S. neglecta can be used as benefit natural sources for food products, supplements, and medicinal plants. HIGHLIGHTS Using GC-MS analysis, there are 30, 39 and 36 phytochemical compounds in propylene glycol, methanol and ethanol extracts from Spirogyra neglecta, respectively The extracts from neglecta possess high nutritional contents of protein, lipid, fiber, ash, moisture, and carbohydrate The extracts from neglecta show relatively low toxic to the RAW 246.7 cells with LC50 &gt;1,000 µg/mL, by MTT assay The extracts from neglecta exhibit anti-inflammatory activity by inhibition of NO production. The propylene glycol extract displays the highest activity compared to others The anti-inflammatory activity of the extracts is partially from Phytol GRAPHICAL ABSTRACT

Comparative study of potent anti-amoebic and anti-inflammatory activities of different extracts from Sida rhombifolia (L)

Background: Sida rhombifolia (L) is a medicinal plant from tropical regions belonging to the Malvaceae family and the plantea kingdom. It is known for its multiple pharmacological properties. The aim of this work was to evaluate the anti-amoebic, and anti-inflammatory potential of Sida rhombifolia aqueous and ethanolic leaf and stem extracts harvested in two localities of Cameroon (Yaoundé and Massangam in the Centre and West regions, respectively). Methods: The anti-amoebic activity was evaluated on a polyxenic culture of Entamoeba histolytica. A primary macrophage culture activated by Saccharomyces cereviseae (SC) was used to evaluate anti-inflammatory potential of the plant extracts. Macrophages were treated with different concentrations (1; 10; 100 and 500 μg/mL) of the extracts for the inhibition of nitric oxide (NO) production and 5-lipoxygenase activity. Methods: The anti-amoebic activity was evaluated on a polyxenic culture of Entamoeba histolytica. A primary macrophage culture activated by Saccharomyces cereviseae (SC) was used to evaluate the anti-inflammatory potential of the plant extracts. Macrophages were treated with different concentrations (1; 10; 100 and 500 μg/mL) of the extracts for the inhibition of nitric oxide (NO) production and 5-lipoxygenase activity. Results: No significant difference was found between the anti-amoebic activity of the ethanolic extract of Yaoundé (Centre region, IC50 = 7.71 μg/mL) and that of ethanolic leaf extract from Massagam (West region IC50 = 7.77 μg/mL) after 72 hours. Among the extracts, ethanolic leaf extracts exhibited the highest anti-amoebic activity after 72 hours of treatment. Metronidazole showed better activity (IC50 = 5.96 µg/mL) in the same periods of time. Phenolic compounds and flavonoid contents were higher in Yaoundé (Centre region) ethanolic leaf extract, proving that these extracts can prevent certain damages linked to a state of oxidative stress. The ethanolic extracts of the leaves significantly inhibited NO production and 5-lipoxygenase activity in macrophages (IC50 of 3.85 µg/mL; 3.99 µg/mL and 36.64 µg/mL; 73.22 µg/mL respectively). Conclusion: This preliminary study shows that the ethanolic extract of S. rhombifolia possesses better anti-amoebic properties and can act at the level of the intestinal mucosa in order to fight against the damage linked to the dysfunction of the inflammatory cells.

Magnolia kobus Extract Inhibits Periodontitis-Inducing Mediators in Porphyromonas gingivalis Lipopolysaccharide-Activated RAW 264.7 Cells.

Periodontitis, a disease caused by inflammation of oral bacteria, contributes to the loss of alveolar bone and destruction of connective tissues. Porphyromonas gingivalis, a Gram-negative bacterium, is known to possess important pathogenic factors for periodontal disease. In this study, we investigated the anti-periodontitis effects of Magnolia kobus extract (MKE) and magnolin as a component of Magnolia kobus (MK) in murine macrophage RAW 264.7 cells stimulated with Porphyromonas gingivalis lipopolysaccharide (LPS). Effects of MKE and magnolin on the mechanism of RAW 264.7 cellular inflammation were determined by analyzing nitric oxide (NO) production and Western blot protein expression (n = 3). MKE/magnolin inhibited NO production without affecting cell survival. MKE/magnolin treatment inhibited LPS-induced pro-inflammatory cytokines, expression levels of matrix metalloproteinases (MMPs such as MMP-1, 3, 8, 9, and 13), and protein levels of inflammatory mediators (such as TNF-α, IL-1β, and mPGES-1). MKE/magnolin also suppressed NF-κB activation by inhibiting the TLR4 signaling pathway. These findings suggest that MKE has a therapeutic effect on inflammatory periodontal disease caused by oral bacterium P. gingivalis and that magnolin is a major functional component in the anti-inflammatory effect of MKE.

Anti-inflammatory kaurane diterpenoids of Erythroxylum bezerrae

Five unusual kaurane diterpenes, designated as bezerraditerpenes A-E (1–5), along with six known ones (6–11), were isolated from the hexane extract of the stems of Erythroxylum bezerrae. Their structures were elucidated based on the interpretation of the NMR spectroscopy, mass spectrometry, and X-ray diffraction analysis. The anti-inflammatory potential of the diterpenes 1–11 was screened through cellular viability and lipopolysaccharide (LPS)-induced nitric oxide (NO) production on murine macrophage-like cells RAW 264.7. Diterpene 6 (cauren-6β-ol) showed potent cytotoxicity and increased ability to inhibit NO production. Diterpenes 1 (bezerraditerpene A), 2 (bezerraditerpene B), and 8 (ent-kaur-16-ene-3β,15β-diol) exhibited the same significant anti-inflammatory activity with NO CI50 inhibition (3.21–3.76 μM) without cytotoxicity, in addition to decreasing the levels of pro-inflammatory cytokines TNF-α and IL-6 in LPS-induced RAW264.7 cells.

Microwave‐Assisted Multicomponent Synthesis of New 6‐Arylated 5‐Hydroxy‐benzo[a]phenazine Derivatives and Their Potential Anti‐inflammatory Activity

AbstractA convenient two step “one‐pot” four‐component synthetic approach was developed for the synthesis of new 6‐arylated 5‐hydroxy‐benzo[a]phenazine derivatives using 2‐hydroxy‐1,4‐naphthoquinone, a variety of aromatic aldehydes, benzene‐1,2‐diamine, and tetronic acid. In all cases, the synthesis proceededviathree key steps including condensation, Michael addition, and tautomerization. The structure of synthesized compounds was elucidated by spectral data. The inhibitory effect of newly synthesized compounds on nitric oxide (NO) production in lipopolysaccharide (LPS)‐ stimulated murine macrophage RAW 264.7 cells was assessed. All products exhibited the highly potential NO production inhibition activity with the IC50values in the range of 3.68–12.14 μM, indicating the critical role of these compounds in the development of potential anti‐inflammation agents.