Nitric Oxide Inhibitory Activity Research Articles

Kamaonensine A-G: Lycaconitine-type C19-diterpenoid alkaloids with anti-inflammatory activities from Delphinium kamaonense Huth

Delphinium kamaonense Huth is a sort of folkloric plant resource which is cultivated and planted with great ornamental and medicinal values. In this work, seven undescribed lycaconitine-type C19-diterpenoid alkaloids, especially a rare skeleton with –CH=N and N-oxide moieties, along with ten known compounds, were isolated from D. kamaonense, of which the structures were determined by various spectroscopic data, combined with calculated electronic circular dichroism (ECD) and single-crystal X-ray diffraction analysis. In vitro nitric oxide inhibitory activities assay of these compounds indicated that lycaconitine-type C19-diterpenoid alkaloids had significant anti-inflammatory inhibitory activities, with kamaonensine E being the most potent (0.9 ± 0.2 μM) stronger than positive (9.0 ± 1.3 μM). In the network pharmacology studies, binding three key targets mitogen-activated protein kinase 8 (MAPK8), mitogen-activated protein kinase 14 (MAPK14), and heat shock protein HSP 90-alpha (HSP90α), the anti-inflammatory mechanism might be related to MAPK signaling pathways. Furthermore, the molecular docking results revealed that the uncommon amides and methylenedioxy groups might be the most two promising pharmacophores for lycaconitine-type C19-diterpenoid alkaloids.

Biological properties of mucus from land snails (Lissachatina fulica) and freshwater snails (Pomacea canaliculata) and histochemical study of mucous cells in their foot.

Mucus derived from many land snails has been extensively utilised in medicine and cosmetics, but some biological activities of the mucus need to be well documented. Nevertheless, most mucus is obtained from land snails, while mucus from freshwater snails has yet to be attended. This study aims to determine and compare mucus's antioxidant and anti-inflammatory activities from the land snail Lissachatina fulica and the freshwater snail Pomacea canaliculata. ABTS, DPPH, reducing power and total antioxidant activity assays were used to evaluate the antioxidant capacity. Inhibition of nitric oxide production in lipopolysaccharide-activated RAW 264.7 cells was performed to determine the anti-inflammatory activity. Additionally, the histochemical analysis of mucous cells in each snail foot was conducted to compare the distribution of mucous cells and types of mucins using periodic acid-Schiff and Alcian blue staining. Mucus from L. fulica and P. canaliculata exhibited antioxidant and anti-inflammatory activities in different parameters. L. fulica mucus has higher total antioxidant (44.71 ±2.11 mg AAE/g) and nitric oxide inhibitory activities (IC50 = 9.67 ±0.31 µg/ml), whereas P. canaliculata mucus has better-reducing power activity (43.63 ±2.47 mg AAE/g) and protein denaturation inhibition (IC50 = 0.60 ±0.03 mg/ml). Histochemically, both species' dorsal and ventral foot regions contained neutral and acid mucins in different quantities. In the dorsal region, the neutral mucins level in L. fulica (16.64 ±3.46%) was significantly higher than that in P. canaliculata (11.19 ±1.50%), while the acid mucins level showed no significant difference between species. Levels of both mucins in the ventral foot region of L. fulica (15.08 ±3.97% and 10.76 ±3.00%, respectively) were significantly higher than those of P. canaliculata (2.25 ±0.48% and 2.71 ±0.56%, respectively). This study revealed scientific evidence of the biological capacity of mucus from L. fulica and P. canaliculata as well as provided helpful information on the region of the foot which produces effective mucus.

Phenolic Constituents of Elsholtzia blanda Benth

Objectives: Elsholtzia blanda Benth. is a Vietnamese medicinal plant, used to treat inflammation, cough, and flu. Therefore, this current study focused on the isolation of the active ingredients from this plant and their NO production inhibitory activity. Methods: E. blanda aerial parts were dried, minced, and ultrasonically extracted with methanol and further separated by various chromatographic methods. The chemical structures of isolates were revealed by nuclear magnetic resonance, high resolution lectrospray ionization mass spectrometry, and circular dichroism spectra. The nitric oxide inhibition effects were evaluated in lipopolysaccharide-activated RAW264.7 cells. Results: Ten phenolic components [1 new (1) and 9 known (2-10)] were isolated and their chemical structures determined. Compound 5 (innovanoside, IC50 = 19.23 ± 1.43 µM) and 6 (maltol- O- β-D-glucopyranoside, IC50 = 21.73 ± 1.27 µM) showed the highest activity, and 2-4 showed moderate inhibition (IC50 = 47.36 ∼ 57.29 µM). The other compounds were inactive with IC50 values >100 µM. Conclusions: One previously undescribed and 9 known phenolic components isolated from E. blanda have been screened for their nitric oxide inhibitory activity. Compounds 2-6 showed moderate to significant inhibition with IC50 values of 19.23∼57.29 µM.

Nitric Oxide Inhibitory Activity of Crude Extracts and Extraction Time and Temperature Optimization of Pectin from Cissampelos pareira Leaves

This research studied crude extracts of Cissampelos pareira leaves using fi ve solvents as hexane, dichloromethane, ethyl acetate, methanol, and ethanol for nitric oxide (NO) inhibitory activity and maximize pectin yields from facile green extraction. Five crude hexane, dichloromethane, ethyl acetate, methanol and ethanol extracts were obtained from the leaves of C. pareira at 0.4%, 0.5%, 0.3%, 3%, and 1%, respectively. The hexane, dichloromethane, and ethyl acetate extracts showed the most potent decrease in NO production with half-maximal inhibitory concentration (IC50) values of 49.85±5.07, 56.26±1.49, and 64.55±2.37 (μg/mL), respectively. Concentrations of all crude extracts of C. pareira indicated no cellular toxicity. Pectin was aqueously extracted at 40 to 90 °C for 15 to 120 min and yields and quality were examined. Highest pectin yield (36.12%) was obtained after 60 min at 60 °C, with quality meeting the criteria established by the International Pectin Producers Association (IPPA) and categorized as high methoxyl pectin.

Five New Glycoside Constituents from the Roots of Gentiana crassicaulis Duthie ex Burk.

Three undescribed glycoside constituents, macrophyllosides E-G and a pair of iridoid glycosides genticrasides A/B, together with eleven known glycoside compounds were isolated from the roots of Gentiana crassicaulis Duthie ex Burk. Their structures were identified by means of spectra analysis and data comparison with previous literatures. Interestingly, the glucose moieties in macrophylloside E and F possess free anomeric hydroxy groups. Genticrasides A/B, identified as a pair of iridoid originated lactones, have not been reported from Gentianaceae family up to now. The anti-inflammatory effects of selected compounds were also evaluated through the nitric oxide (NO) production inhibition in lipopolysaccharides (LPS)-induced RAW264.7 macrophage cells. In which, macrophyllosides G and D showed NO inhibitory activities with rates of 76.14±4.02 % and 52.44±8.29 % at 100 μg/mL.

Phytochemical screenings and evaluations of antibacterial and antioxidant activities of methanolic leaf extract of Senna auriculata (L). Roxb

The current study examineed the "Phytochemical contents, antimicrobial and antioxidant activities of the methanolic leaf extract of S. auriculata". Methanol was used to extract a leaf sample from a plant. The phytoconstituents and functional groups in the leaf extract had been investigated using Gas Chromatography-Mass Spectroscopy (GC-MS) and Fourier Transform Infrared (FTIR) analysis. Concurrently, the agar well-plate method was used to assess antimicrobial activity against ten bacterial strains. DPPH (1,1-diphenyl-2-picrylhydrazyl), reducing power activity, phosphomolybdenum activity, hydrogen peroxide activity, and nitric oxide inhibitory activity were employed to assess antioxidant activity. Carbohydrates, protein, tannins, saponins, and terpenoids were found in the phytochemical analysis. The GC-MS study of the leaf extract revealed the presence of 13 major bioactive substances with antimicrobial, free radical scavenging, and anticancer properties. The appearance of distinctive peak values with various functional groups, such as alcohol, alkanes, aromatic, esters, and amines, was indicated by the FTIR result. The leaf extract exhibited a potent antibacterial effect against all pathogens tested. The highest activity against A. hydrophila (15±0.6 mm) was found at a 100 µg/mL concentration. The antioxidant properties of leaf extract increased as concentration was increased. The leaf extract contains 108.13 mg GAE/g and 61.25 mg RE/g of phenolic and flavonoid content, respectively. Finally, the methanolic leaf extract of S. auriculata was found to have powerful antibacterial and antioxidant features and could be a valuable source of natural compounds for creating new medications. Although S. auriculata has been extensively studied for its antibacterial activity against pathogenic organisms, the findings showed that it is also effective against the fish pathogen A. hydrophila. More investigation is required to find and identify the biologically active compounds responsible for the plant’s antibacterial and antioxidant activity.

Evaluation of Phenolic Content, Anti-oxidant and modulation of blood indices of Pavetta crassipes

IntroductionPavetta crassipes is a medicinal plant with various documented biological activities. It has a folkloric use as an anti-viral therapy and pharmacologically documented anti-microbial activity. However, its immune modulatory property has not been explored. The study is designed to evaluate the phytochemical profile as well as the anti-oxidant and immunomodulatory potential of the methanol extract of Pavetta crassipes leaf. Methodology In vitro antioxidants activity was determined by nitric oxide inhibitory assay. phenolic and flavonoid content of the extract was also determined. The immunomodulatory activity was evaluated using cyclophosphamide induced immunomodulation model in mice. Phytochemical evaluation of leaf extract was done using HPLC analyses. Results were expressed as the mean ± SEM, IC50 value for the antioxidant activity was determined, One-way ANOVA was used for differences in mean followed by Dunnett’s test for multiple comparison for the immunomodulatory activity. To test for level of significance, P< 0.05 was considered significant. ResultsThe extract had phenolic and flavonoid contents of 17.6 ±0.1 mg/GAE/g and 8.4 ± 0.3 mg/QE/g respectively. The extract also showed nitric oxide inhibitory antioxidant activity with IC50 of 2.3± 0.4 while gallic and ascorbic acid had IC50 of 1.6 ±0.1 and 8.0 ±0.6 respectively. P. crassipes leaf extract indicated a significant (p<0.05) countering influence to cyclophosphamide induced decrease in total white blood count, differential leucocyte counts and red blood count. HPLC analysis indicated the presence of phenolic compounds such a rutin, quercetin and chlorogenic acid. ConclusionThe phytochemical profile, anti-oxidant and immunomodulatory properties of the methanol extract of P. crassipes leaf as evaluated in this study corroborates and justifies its folkloric use.

Novel pterostilbene derivatives ameliorate heart failure by reducing oxidative stress and inflammation through regulating Nrf2/NF-κB signaling pathway

Pterostilbene is a demethylated resveratrol derivative with attractive anti-inflammatory, anti-tumor and anti-oxidative stress activities. However, the clinical use of pterostilbene is limited by its poor selectivity and druggability. Heart failure is a leading cause of morbidity and mortality worldwide, which is closely related to enhanced oxidative stress and inflammation. There is an urgent need for new effective therapeutic drugs that can reduce oxidative stress and inflammatory responses. Therefore, we designed and synthesized a series of novel pterostilbene chalcone and dihydropyrazole derivatives with antioxidant and anti-inflammatory activities by the molecular hybridization strategy. The preliminary anti-inflammatory activities and structure-activity relationships of these compounds were evaluated by nitric oxide (NO) inhibitory activity in lipopolysaccharide (LPS)-treated RAW264.7 cells, and compound E1 exhibited the most potent anti-inflammatory activities. Furthermore, pretreatment with compound E1 decreased reactive oxygen species (ROS) generation both in RAW264.7 and H9C2 cells by increasing the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), as well as downstream antioxidant enzymes superoxide dismutase 1 (SOD1), catalase (CAT) and glutathione peroxidase 1 (GPX1). In addition, compound E1 also significantly inhibited LPS or doxorubicin (DOX)-induced inflammation in both RAW264.7 and H9C2 cells through reducing the expression of inflammatory cytokines by inhibiting nuclear factor-κB (NF-κB) signaling pathway. Moreover, we found that compound E1 improved DOX-induced heart failure by inhibiting inflammation and oxidative stress in mouse model, which is mediated by the potential of antioxidant and anti-inflammatory activities. In conclusion, this study demonstrated the novel pterostilbene dihydropyrazole derivative E1 was identified as a promising agent for heart failure treatment.

New 5-methyl-4-hydroxycoumarin polyketide derivatives from Gerbera delavayi with anti-inflammatory activity

Five new 5-methyl-4-hydroxycoumarin polyketide derivatives (MPDs), delavayicoumarins A-E (1–5), were isolated from the whole plants of Gerbera delavayi. Among them, compounds 1–3 are the common monoterpene polyketide coumarins (MPCs), while 4 is a modified MPC with both the lactone ring contracted to a five-membered furan ring and a carboxyl at C-3, and 5 is a pair of unusual phenylpropanoid polyketide coumarin enantiomers (5a and 5b), featuring a phenylpropanoid unit at C-3. The planar structures were elucidated by spectroscopic methods and biosynthetic arguments, and the absolute configurations of 1–3, 5a and 5b were confirmed by calculated electronic circular dichroism (ECD) experiment. Furthermore, compounds 1–3, (+)-5 and (−)-5 were tested for the nitric oxide (NO) inhibitory activity by using lipopolysaccharide (LPS)-induced RAW 264.7 cells in vitro. The results showed that compounds 1–3, (+)-5 and (−)-5 remarkably inhibited NO production at the concentration of 10.0 μM, exhibiting that they have significant anti-inflammatory activity.

Labdane-type diterpenoids and sesquiterpenes from Curcuma aromatica and their nitric oxide inhibitory activity in lipopolysaccharide-stimulated RAW264.7 macrophages

One new labdane-type diterpenoid, 3β,15-dihydroxylabda-8(17),12E-dien-16,15-olide (1) named curcumatin and twelve known compounds, coronarin D (2), isocoronarin D (3), (E)-labda-8(17),12-diene-15,16-dial (4), zerumin A (5), (E)-labda-8(17),12-dien-15,16-dioic acid (6), furanodiene (7), linderazulene (8), zedoarol (9), zedoarondiol (10), germacrone-1,10-epoxide (11), germacrone-4,5-epoxide (12), and zingiberenol (13) were isolated from the ethanol extract of the roots of Curcuma aromatica Salisb. Their structures were elucidated by 1D-, 2D-NMR spectroscopic analysis, HR-ESI-MS, and comparing with the NMR data reported in the literature. Compounds 2, 5, and 13 significantly inhibited the nitric oxide production effect in LPS-stimulated RAW 264.7 macrophages with IC50 values of 8.8 ± 1.7, 4.0 ± 0.9, and 6.2 ± 0.4 µM, respectively.

Potent nitric oxide inhibitory sesquiterpenoids from the rhizome of Curcuma aromatica Salisb.

One new sesquiterpenoid, curcaromatin (1), together with twenty-one known compounds 2–22, were isolated from the rhizomes of Curcuma aromatica Salisb. (Zingiberaceae). Their structures were established by extensive spectroscopic (1D and 2D NMR and HR-MS) analysis. Most of the isolated compounds were investigated for nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW264.7 cells. (−)-Xanthorrhizol (3) displayed the strongest NO inhibitory activity with an IC50 value of 4.3 μM, which was 3.7-fold more active than the reference compound, aminoguanidine (IC50 15.9 μM). The selectivity index (SI > 28.1) of compound 3 was almost 3-fold higher than that of aminoguanidine.

Chemical constituents isolated from Hosta ensata and their anti-inflammatory activities

A new phenol derivative, hostaphenol A (1), along with 16 known ones (2–17) were isolated from an ethanolic extract of the whole plants of Hosta ensata F. Maek. Their structures were elucidated by HRMS and NMR data as well as comparison with those reported in literature. The report of the first cyclopeptide and compounds 5, 6, 8, 10, 12–15, and 17 in the Asparagaceae family. Compound 2, as well as compounds 3, 4, 7, 9, 11, and 16 were reported for the first time from the Hosta genus and this plant, respectively. All compounds significantly reduced nitric oxide (NO) production at a concentration of 40 μM with no toxicity in RAW 264.7 cells stimulated by lipopolysaccharide. Among them, compounds 2–5 (40 μM) exerted obvious NO inhibitory activities, and their inhibition rate was exceeded 50%.

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.

Separation and identification of terpene-conjugated curcuminoids based on LC-MS/MS and their in vitro anti-inflammatory activities.

Terpene-conjugated curcuminoids are conjugates of curcuminoids and bisabolanes in the rhizomes of Curcuma longa L. The fragmentation pathways of known three terpene-conjugated curcuminoids (bisabolocurcumin-ether, bisabocurcumin and demethoxybisabolocurcumin ether) and curcumin, demethoxycurcumin and bisdemethoxycurcumin were investigated using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry in negative mode to rapidly search and discover similar unknown compounds of the acetone fraction of turmeric. Subsequently, compounds 1-3 were founded in the acetone fraction based on molecular weight and above fragmentation pathways (the characteristic fragment ions, the most and second most abundant fragment ions produced in MS2 spectra). Terpecurcumin X (1) and terpecurcumin Y (3) were further separated by LC-MS/MS guided isolation technique to verify their structures by nuclear magnetic resonance, electrospray ionization high-resolution mass spectroscopy, ultraviolet and visible spectra and infrared spectra. Interestingly, 1 and 3 were new compounds. The results indicate the feasibility and significant advantages of LC-MS/MS for the rapid discovery and analysis of new constituents in traditional Chinese medicine. In vitro, Terpene-conjugated curcuminoids had better nitric oxide inhibitory activity than the other seven curcuminoids (demethoxycurcumin, bisdemethoxycurcumin, curdione, curcumenone, bisacurone, curcumenol, and germacron). This article is protected by copyright. All rights reserved.

Phytochemical Profiles, Antioxidant and Nitric Oxide Inhibitory Activities of Cajanus cajan Seeds at Different Ripening Stages

Phytochemical Profiles, Antioxidant and Nitric Oxide Inhibitory Activities of Cajanus cajan Seeds at Different Ripening Stages

Anti-inflammatory Quinoline Alkaloids from the Roots of Waltheria indica

Sixteen new quinoline alkaloids (1a-7, 8a, 9, 10, 13-15, 17, and 21) and 10 known analogs (8b, 11, 12, 16, 18-20, and 22-24), along with three known cyclopeptide alkaloids (25-27), were isolated from the roots of Waltheria indica. The structures of the new compounds were elucidated by detailed NMR and circular dichroism with computational support and mass spectrometry data interpretation. Anti-inflammatory potential of isolates was evaluated based on inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production and tumor necrosis factor-alpha (TNF-α)-induced nuclear factor kappa B (NF-κB) activity with cell culture models. In the absence of cell growth inhibition, compounds 6, 8a, 9-11, 13, 21, and 24 reduced TNF-α-induced NF-κB activity with IC50 values ranging from 7.1 to 12.1 μM, comparable to the positive control (BAY 11-7082, IC50 = 9.7 μM). Compounds 6, 8a, 8b, and 11 showed significant NO-inhibitory activity with IC50 values ranging from 11.0 to 12.8 μM, being more active than the positive control (l-NMMA, IC50 = 22.7 μM). Structure-activity relationships indicated that NO inhibitory activity was significantly affected by C-8 substitution. Inhibition of LPS-induced nitric oxide synthase (iNOS) by 8b [(5S)-waltherione M, IC50 11.7 ± 0.8 μM] correlated with inhibition of iNOS mRNA expression. The biological potential of W. indica metabolites supports the traditional use of this plant for the treatment of inflammatory-related disorders.

Polyoxypregnane Glycosides from Root of Marsdenia tenacissima and Inhibited Nitric Oxide Levels in LPS Stimulated RAW 264.7 Cells.

Six new polyoxypregnane glycosides, marstenacisside F1-F3 (1-3), G1-G2 (4-5) and H1 (6), as well as 3-O-β-D-glucopyranosyl-(1→4)-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α,12β-di-O-benzoyl-tenacigenin B (7), were isolated from the roots of Marsdenia tenacissima. Their structures were established by an extensive interpretation of their 1D and 2D NMR and HRESIMS data. Compounds 1-7 were tenacigenin B derivatives with an oligosaccharide chain at C-3. This was the first time that compound 7 had been isolated from the title plant and its 1H and 13C NMR data were reported. Compounds 4 and 5 were the first examples of C21 steroid glycoside bearing unique β-glucopyranosyl-(1→4)-β-glucopyranose sugar moiety. All the isolated compounds were evaluated for anti-inflammatory activity by inhibiting nitric oxide (NO) production in the lipopolysaccharide-induced RAW 264.7 cells. The results showed that marstenacisside F1 and F2 exhibited significant NO inhibitory activity with an inhibition rate of 48.19 ± 4.14% and 70.33 ± 5.39%, respectively, at 40 μM, approximately equal to the positive control (L-NMMA, 68.03 ± 0.72%).

Hyperxylones A and B, two polycyclic polyprenylated acylphloroglucinols with a benzoyl substituted bicyclo[3.2.1]octane core from Hypericum beanii

Two new polycyclic polyprenylated acylphloroglucinols (PPAPs) possessing a rare benzoyl substituted bicyclo[3.2.1]octane core, hyperxylones A (1) and B (2), along with three new dearomatized isoprenylated acylphloroglucinols (DIAPs), hyperxylones C − E (3–5), were isolated from the roots of Hypericum beanii. The structures of 1–5 were determined by high-resolution electrospray ionization mass spectroscopy (HRESIMS) and 1D/2D nuclear magnetic resonance (NMR) spectroscopic analyses, gauge-independent atomic orbital (GIAO) NMR calculations, and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 were biomimetically semi-synthesized starting from 5 and 4, respectively, enabling the correct stereochemical assignment of 5 and 4. Moreover, compounds 1 and 2 showed anti-nonalcoholic steatohepatitis (NASH) activity by inhibiting lipid deposition in L02 cells; compounds 3 and 5 exhibited nitric oxide (NO) inhibitory activity in lipopolysaccharides (LPS)-induced RAW264.7 cells.

Novel tryptanthrin derivatives with benzenesulfonamide substituents: Design, synthesis, and anti-inflammatory evaluation

Herein, two series of tryptanthrin derivatives with benzenesulfonamide substituents were designed and synthesized to discover novel anti-inflammatory agents. The anti-inflammatory activities of all derivatives were screened by evaluating their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells. Among them, compound 8j exhibited the best NO inhibitory activity (IC50 = 1.25 ± 0.21 μM), with no obvious toxicity. Further evaluation showed that 8j could also significantly reduce the levels of pro-inflammatory cytokines interleukin-1β (IL-1β, IC50 = 8.48 ± 0.23 μM) and tumor necrosis factor-α (TNF-α, IC50 = 11.53 ± 0.35 μM) and downregulate the LPS-induced expression of iNOS and COX-2. Reverse docking of 8j suggested p38α as the molecular target, which is a well-known crucial player in the p38 MAPK signaling pathway that controls the transcription of pro-inflammatory mediators. Cellular thermal shift assay showed that 8j efficiently stabilized p38α in LPS-treated RAW264.7 cells. Western blot showed that inflammatory response was inhibited by 8j through inhibiting the phosphorylation of p38α and MK2 in the p38 MAPK signaling pathway. Finally, In vivo studies showed that 8j could significantly ameliorate the degree of foot swelling and knee joint pathology in adjuvant-induced arthritis (AIA) rats and reduce levels of TNF-α and IL-1β in serum, achieving the effect of protecting synovial tissue and ameliorating arthritis. These findings suggested that 8j may be a promising compound for further development of anti-inflammatory agents.

Spirulina platensis Suppressed iNOS and Proinflammatory Cytokines in Lipopolysaccharide-Induced BV2 Microglia.

The disease burden of neurodegenerative diseases is on the rise due to the aging population, and neuroinflammation is one of the underlying causes. Spirulina platensis is a well-known superfood with numerous reported bioactivities. However, the effect of S. platensis Universiti Malaya Algae Culture Collection 159 (UMACC 159) (a strain isolated from Israel) on proinflammatory mediators and cytokines remains unknown. In this study, we aimed to determine the anti-neuroinflammatory activity of S. platensis extracts and identify the potential bioactive compounds. S. platensis extracts (hexane, ethyl acetate, ethanol, and aqueous) were screened for phytochemical content and antioxidant activity. Ethanol extract was studied for its effect on proinflammatory mediators and cytokines in lipopolysaccharide (LPS)-induced BV2 microglia. The potential bioactive compounds were identified using liquid chromatography-mass spectrometric (LC-MS) analysis. Ethanol extract had the highest flavonoid content and antioxidant and nitric oxide (NO) inhibitory activity. Ethanol extract completely inhibited the production of NO via the downregulation of inducible NO synthase (iNOS) and significantly reduced the production of tumor necrosis factor (TNF)-α and interleukin (IL)-6. Emmotin A, palmitic amide, and 1-monopalmitin, which might play an important role in cell signaling, have been identified. In conclusion, S. platensis ethanol extract inhibited neuroinflammation through the downregulation of NO, TNF-α and IL-6. This preliminary study provided insight into compound(s) isolation, which could contribute to the development of precision nutrition for disease management.