A Study on the Anti-NF-κB, Anti-Candida, and Antioxidant Activities of Two Natural Plant Hormones: Gibberellin A4 and A7.

INTRODUCTION: Gibberellins (GA) are terpenoids that serve as important plant hormones by acting as growth and response modulators against injuries and parasitism. In this study, we investigated the in vitro anti-NF-κB, anti-Candida, and antioxidant activity of gibberellin A4 (GA4) and A7 (GA7) compounds, and further determined their toxicity in vivo. METHODS: GA4 and GA7 in vitro toxicity was determined by MTT method, and nontoxic concentrations were then tested to evaluate the GA4 and GA7 anti-NF-κB activity in LPS-activated RAW-luc macrophage cell culture (luminescence assay). GA4 in silico anti-NF-κB activity was evaluated by molecular docking with the software "AutoDock Vina", "MGLTools", "Pymol", and "LigPlot+", based on data obtained from "The Uniprot database", "Protein Data Bank", and "PubChem database". The GA4 and GA7 in vitro anti-Candida effects against Candida albicans (MYA 2876) were determined (MIC and MFC). GA7 was also evaluated regarding the viability of C. albicans preformed biofilm (microplate assay). In vitro antioxidant activity of GA4 and GA7 was evaluated against peroxyl radicals, superoxide anions, hypochlorous acid, and reactive nitrogen species. GA4 and GA7 in vivo toxicity was determined on the invertebrate Galleria mellonella larvae model. RESULTS: Our data show that GA4 at 30 µM is nontoxic and capable of reducing 32% of the NF-κB activation on RAW-luc macrophages in vitro. In vitro results were confirmed via molecular docking assay (in silico), since GA4 presented binding affinity to NF-κB p65 and p50 subunits. GA7 did not present anti-NF-κB effects, but exhibited anti-Candida activity with low MIC (94 mM) and MFC (188 mM) values. GA7 also presented antibiofilm properties at 940 mM concentration. GA4 did not present anti-Candida effects. Moreover, GA4 and GA7 showed antioxidant activity against peroxyl radicals, but did not show scavenging activity against the other tested radicals. Both compounds did not affect the survival of G. mellonella larvae, even at extremely high doses (10 g/Kg). CONCLUSION: Our study provides preclinical evidence indicating that GA4 and GA7 have a favorable low toxicity profile. The study also points to GA4 and GA7 interference with the NF-κB via, anti-Candida activity, and a peroxyl radical scavenger, which we argue are relevant biological effects.

The phytoactive constituents of Eugenia selloi B.D. Jacks (pitangatuba): Toxicity and elucidation of their anti-inflammatory mechanism(s) of action.

We determined the phytochemical composition, anti-inflammatory mechanism of action, ROS/RNS scavenging capacity and systemic toxicity of a purified subfraction (S8) of Eugenia selloi. The composition of S8 was assessed by LC-ESI-QTOF-MS; the anti-inflammatory activity in RAW264.7 macrophages through NF-κB activation and biomarkers by multiplex in THP-1 cells; neutrophil migration, intravital microscopy and ICAM-1 expression in mice; NETs formation and CD11b expression; S8 scavenging capacity of ROS/RNS; toxicity in Galleria mellonella larvae model. Coumaric acid, quercetrin and vanillic acid were identified. S8 decreased NF-κB activation, IL-1ß, IL-6, IL-10, MDC and MCP-1 levels, reduced neutrophil migration and ICAM-1 expression in mice; S8 did not interfere NET formation and CD11b expression, exhibited high antioxidant and showed negligible toxicity. E. selloi proved to be a promising, yet underexplored source of bioactive compounds, which can be useful employed in agribusiness and in the pharmaceutical and food industry to develop new products or human health supplies.

Phenolic profile and potential beneficial effects of underutilized Brazilian native fruits on scavenging of ROS and RNS and anti-inflammatory and antimicrobial properties.

Brazilian native fruits (BNF) have aroused interest of researchers and consumers for their great human health benefits. In this study, five BNF (Byrsonima lancifolia, Campomanesia phaea, Jacaratia spinosa, Solanum alternatopinnatum and Acnistus arborescens) were tested for their polyphenolic compounds by LC-ESI-MS/MS, reactive species deactivation (ROO˙, O2˙-, HOCl and NO˙), anti-inflammatory properties in vivo, and in vitro antimicrobial activity - with determination of putative mechanism(s) of action. Eighty-one polyphenols were identified, which exhibited a significant capacity to deactivate both ROS and RNS. C. phaea extract had the highest capacity to scavenge ROO˙ (68.94 µmol TE per g), O2˙- (IC50: 575.36 µg mL-1) and NO˙ (IC50: 16.96 µg mL-1), which may be attributed to the presence of ellagitanins. B. lancifolia decreased neutrophil influx into the peritoneal cavity of mice by 50% as compared to carrageenan and reduced Candida albicans biofilm viability by 3 log10 possibly due to complexation with cell membrane ergosterol. In summary, the BNF presented herein are good sources of bioactive compounds with positive effects on deactivation of biological reactive species, as well as with anti-inflammatory and antimicrobial activities, which can be altogether highly beneficial to human health.

Anti-inflammatory and antioxidant potential, in vivo toxicity, and polyphenolic composition of Eugenia selloi B.D.Jacks. (pitangatuba), a Brazilian native fruit.

Brazilian native fruits are a rich source of polyphenolic compounds that can act as anti-inflammatory and antioxidant agents. Here, we determined the polyphenolic composition, anti-inflammatory mechanism of action, antioxidant activity and systemic toxicity in Galleria mellonella larvae of Eugenia selloi B.D.Jacks. (synonym Eugenia neonitida Sobral) extract (Ese) and its polyphenol-rich fraction (F3) obtained through bioassay-guided fractionation. Phenolic compounds present in Ese and F3 were identified by LC-ESI-QTOF-MS. The anti-inflammatory activity of Ese and F3 was tested in vitro and in vivo through NF-κB activation, cytokine release and neutrophil migration assays. The samples were tested for their effects against reactive species (ROO•, O2•-, HOCl and NO•) and for their toxicity in Galleria mellonella larvae model. The presence of hydroxybenzoic acid, ellagitannins and flavonoids was identified. Ese and F3 reduced NF-κB activation, cytokine release and neutrophil migration, with F3 being three-fold more potent. Overall, F3 exhibited strong antioxidant effects against biologically relevant radicals, and neither Ese nor F3 were toxic to G. mellonella larvae. In conclusion, Ese and F3 revealed the presence of phenolic compounds that decreased the inflammatory parameters evaluated and inhibited reactive oxygen/nitrogen species. E. selloi is a novel source of bioactive compounds that may provide benefits for human health.

Effects of academic stress on the levels of oral volatile sulfur compounds, halitosis-related bacteria and stress biomarkers of healthy female undergraduate students.

To investigate whether academic stress changes the salivary microbiota and its relationship with salivary parameters, evaluating the effects on the production of volatile sulfur compounds (VSCs) in healthy women. Fifty-five women who were enrolled in a four-year Dentistry course were assessed for academic stress by the questionnaire Maslach Burnout Inventory-Student Survey and were then classified into 'Not Stressed' and 'Stressed' groups. Cortisol and alpha-amylase (AA) were measured as physiological stress biomarkers. Oral Chroma™ gas chromatograph was used to measure concentrations of hydrogen sulfide (H2S), methyl mercaptan and dimethyl sulfide. Salivary proteins were evaluated by western blot. Quantitative polymerase chain reaction was used to identify the salivary amounts of halitosis-associated bacteria. The 'Stressed' volunteers showed higher levels of H2S, AA, Fusobacterium nucleatum and total bacteria, compared to the 'Not Stressed' individuals (p < 0.05; Mann-Whitney test). Salivary proteins showed no differences between groups (p > 0.05; Mann-Whitney test). Academic stress was positively correlated with H2S, total bacteria and F. nucleatum counts, while F. nucleatum was positively correlated with AA. H2S showed positive correlations with AA and Solobacterium moorei (p < 0.05; Spearman correlation). Beta-defensin (BD) presented negative correlations with H2S and S. moorei (p < 0.05; Spearman correlation). Academic stress increased salivary F. nucleatum and total bacteria, as well as AA activity. The protein BD showed important correlations with bacteria and VSC. These changes appeared to be accountable for increased H2S production in the stressed women.

Alkaline conditions better extract anti-inflammatory polysaccharides from winemaking by-products.

Winemaking generates large amounts of by-products, a well recognized source of phenolic compounds. However, less attention has been paid to the polysaccharide-rich fraction (PRF) and effects of fractionation techniques on its potential bioactivity. Therefore, PRFs from Syrah and Tempranillo winemaking by-products were extracted under aqueous (neutral pH conditions), acidic and alkaline conditions. PRFs were screened for their monosaccharide composition, uronic acid content, homogeneity and molecular weight. Anti-inflammatory activity of PRFs were evaluated on stimulated RAW 264.7 macrophages. PRF obtained in water and/or under acidic conditions showed heterogeneous profiles. As like as in the others, a heterogeneous and complex profile was detected in extracts procured under alkaline conditions. A high content of uronic acid was found in aqueous extracts, thus indicating the presence of pectin. Pectin and hemicellulose were present in PRFs procured under acidic conditions. Alkaline conditions rendered extracts containing a complex mixture of monosaccharides, mainly xylose. This latter PRF was the only one exhibiting anti-inflammatory potential (at 100 µg/mL) by reducing the release of TNF-α and activation of NF-κB in LPS-activated RAW 264.7 macrophages, with no effect on cell viability. Regardless of the grape variety, PRFs obtained under alkaline conditions were the best option to obtain bioactive polysaccharides with potential application as a source of anti-inflammatory compounds. A complex mixture of polymers may be responsible for the anti-inflammatory effects. Finally, according to results procured by NMR, it is possible to suggest that bioactive fractions are composed of a chain of α-L-Araf-(1 → 3) linked, ß-D-Xylp- (1 → 4), α-D-Glcp-(1 → 4) linked, α-D-GalpA-(1 → 4), α-D-Gal-(1 → 2) forming possible RG I and RG II and xylan chains.

Anti-inflammatory and anti-Candida Effects of Brazilian Organic Propolis, a Promising Source of Bioactive Molecules and Functional Food.

Brazilian organic propolis (BOP) is an unexplored Brazilian propolis that is produced organically and certified according to international legislation. Our results showed that BOP has strong anti-inflammatory effects and acts by reducing nuclear factor κB activation, tumor necrosis factor α release, and neutrophil migration. In addition, BOP6 exhibited antifungal activity on planktonic and biofilm cultures of Candida albicans, Candida glabrata, Candida tropicalis, Candida krusei, and Candida parapsisolis and reduced in vitro yeast cell adhesion to human keratinocytes at sub-inhibitory concentrations. BOP demonstrated significantly low toxicity in Galleria melonella larvae at antifungal doses. Lastly, a chemical analysis revealed the presence of caffeoyltartaric acid, 3,4-dicaffeoylquinic acid, quercetin, and gibberellins A7, A9, and A20, which may be responsible for the biological properties observed. Thus, our data indicate that BOP is a promising source of anti-inflammatory and antifungal molecules that may be used as a functional food.

Comprehensive characterization of bioactive phenols from new Brazilian superfruits by LC-ESI-QTOF-MS, and their ROS and RNS scavenging effects and anti-inflammatory activity.

Brazilian native fruits (BNF) remain unexplored and underutilized resources with a high potential to improve human health and wellness. In our study, five new BNF (Eugenia stipitata, Sageretia elegans, Byrsonima arthropoda, Spondias mombin andRubus rosaefolius)were evaluated for their phenolic composition by LC-ESI-QTOF-MS; and for their ROS and RNS scavenging effects (ROO, O2-, NO, HOCl); in vivo anti-inflammatory activity (neutrophil migration); and in vivo acute toxicity in Galleria mellonella. Eighty-six phenolic compounds were identified, including hydroxybenzoic acids, hydroxycinnamic acids, flavonoids, anthocyanins and ellagitannins, several of which had never been reported in BNF. The BNF exhibited high antioxidant effects against biologically relevant radicals, and treated animals showed decreased neutrophil influx and NF-kB activation. Thus, these BNF are good sources of antioxidant and anti-inflammatory molecules that can be beneficial for human health as functional foods. Based on their bioactivity, they can be considered as new Brazilian superfruits.

Stress-related salivary proteins affect the production of volatile sulfur compounds by oral bacteria.

OBJECTIVE: To determine whether stress-related substances and sex hormones influence the growth and in vitro production of volatile sulfur compounds (VSCs) by Solobacterium moorei and Fusobacterium nucleatum. MATERIALS AND METHODS: Bacteria growth and VSCs production were evaluated in the presence of alpha-amylase, beta-defensin-2, mucin, estradiol, and progesterone. Growth was evaluated by colony counting, and the production of the VSCs hydrogen sulfide (H2 S) and methyl mercaptan (CH3 SH) was measured using the Oral Chroma™ instrument. RESULTS: Mucin induced the production of H2 S by both bacteria, but had a slight inhibitory effect on CH3 SH production by F. nucleatum. It also increased the viability of F. nucleatum. Alpha-amylase increased H2 S production by S. moorei and CH3 SH production by F. nucleatum, but had no effect on H2 S production by F. nucleatum. No substance altered the viability of S. moorei. No effects of beta-defensin-2, estradiol, or progesterone were observed. CONCLUSION: The salivary stress-related proteins mucin and alpha-amylase altered VSCs production by F. nucleatum and S. moorei, favoring H2 S production. These findings are a step toward understanding the relation between stress and increased amounts of H2 S.

Bioprospection of Eugenia brasiliensis, a Brazilian native fruit, as a source of anti-inflammatory and antibiofilm compounds.

The anti-inflammatory and antibiofilm activities as well as toxicity and chemical profile of Eugenia brasiliensis pulp extract (EBE), were evaluated. EBE chemical profile and phenolic content were determined by LC-MS/MS. EBE was tested for its in vitro and in vivo anti-inflammatory activity, including TNF-α release, NF-кB activation, neutrophil migration and paw edema. The MIC/MBC and antibiofilm activities were tested against methicillin sensitive and resistant Staphylococcus aureus, Escherichia coli, Pseudomona aeruginosa, Streptococcus mutans, and Lactobacillus acidophilus. EBE acute toxicity was evaluated in Galleria mellonella and RAW 264.7 macrophage. EBE total phenolic content was 389.88 ±â€¯3.48 mg GAE/g with identified polyphenols. EBE decreased TNF-α release in vivo and in vitro, NF-кB activation, neutrophil influx into peritoneal cavity, and it showed maximal inhibition of paw edema after 2 h. MIC of EBE ranged from 62.5-500 µg/mL while MBC values were >500 µg/mL, with a decrease in L. acidophilus biofilm formation. EBE showed negligible toxicity in larvae and macrophage cells. Our findings open new perspectives concerning EBE application as source of anti-inflammatory and antibiofilm molecules as a functional food, pharmaceutical lead or agribusiness commodity.

Isoflavonoids from Brazilian red propolis down-regulate the expression of cancer-related target proteins: A pharmacogenomic analysis.

Vestitol and neovestitol are bioactive isoflavonoids isolated from Brazilian red propolis, a unique Apis melifera type of propolis botanically originated from Dalbergia ecastophyllum. Although these molecules have relevant biological effects, including anticancer and immunomodulatory activities, their mechanism(s) of action and the affected pathways remain largely unknown. Here, we carried out a pharmacogenomic analysis to investigate the effects of vestitol and neovestitol on the whole-genome expression in human tumor cells, particularly cancer-related target proteins. HeLa cells were exposed to the compounds at IC20 and genomic information of treated cells was analyzed using the Illumina transcriptome system and GeneGo MetaCore software. Our results showed that vestitol (IC20  = 214.7 µM) reduced the expression of genes enrolled with the alpha tubulin (fold -3.7), tubulin in microtubules (fold -3.7), and histone h3 (fold = -3.03), and that treatment with neovestitol (IC20  = 102.91 µM) downregulated prostaglandin E synthase gene (fold = -3.12), which are considered ideal targets for anticancer therapy. These data open avenues for the study of vestitol and neovestitol as potential promising candidates for anticancer therapy. Toxicological, non-clinical, and clinical validation of the findings presented herein is needed.

The use of Brazilian propolis for discovery and development of novel anti-inflammatory drugs.

Anti-Inflammatory drugs have been routinely used in the management of acute and chronic inflammatory conditions. Nevertheless, their undesirable side and adverse effects have encouraged the development of more selective, tolerable and efficacious drugs able to modulate the inflammatory process through distinct mechanisms than those of drugs currently available in the market, for instance, inhibition of leukocyte recruitment (chemotaxis, rolling, adhesion and transmigration). Natural products, including Brazilian propolis, have been considered a rich source of anti-inflammatory molecules due to a very complex phytochemical diversity. Brazil has at least thirteen distinct types of propolis and many bioactive compounds have been isolated therefrom, such as apigenin, artepillin C, vestitol, neovestitol, among others. These molecules were proven to play a significant immunomodulatory role through (i) inhibition of inflammatory cytokines (e.g. TNF-α) and chemokines (CXCL1/KC and CXCL2/MIP2); (ii) inhibition of IκBα, ERK1/2, JNK and p38MAPK phosphorylation; (iii) inhibition of NF-κB activation; and (iv) inhibition of neutrophil adhesion and transmigration (ICAM-1, VCAM-1 and E-selectin expression). In this review, we shed light on the new advances in the research of compounds isolated from Brazilian propolis from Apis mellifera bees as potentially novel anti-inflammatory drugs. The compilation of data and insights presented herein may open further avenues for the pharmacological management of oral and systemic inflammatory conditions. Further research should focus on clinical and acute/chronic toxicological validation of the most promising compounds described in this review.

Changes in salivary microbiota increase volatile sulfur compounds production in healthy male subjects with academic-related chronic stress.

OBJECTIVE: To investigate the associations among salivary bacteria, oral emanations of volatile sulfur compounds, and academic-related chronic stress in healthy male subjects. MATERIALS AND METHODS: Seventy-eight healthy male undergraduate dental students were classified as stressed or not by evaluation of burnout, a syndrome attributed to academic-related chronic stress. This evaluation was carried out using the Maslach Burnout Inventory-Student Survey questionnaire. Oral emanations of hydrogen sulfide, methyl mercaptan, and dimethyl sulfide were measured using an Oral Chroma™ portable gas chromatograph. The amounts in saliva of total bacteria and seven bacteria associated with halitosis were quantified by qPCR. The in vitro production of H2S by S. moorei and/or F. nucleatum was also measured with the Oral Chroma™ instrument. RESULTS: The stressed students group showed increased oral emanations of hydrogen sulfide and dimethyl sulfide, together with higher salivary Solobacterium moorei levels (p < 0.05, Mann Whitney test). There were moderate positive correlations between the following pairs of variables: Fusobacterium nucleatum and S. moorei; F. nucleatum and hydrogen sulfide; Tannerella forsythia and F. nucleatum; T. forsythia and S. moorei. These correlations only occurred for the stressed group (p < 0.05, Spearman correlation). The in vitro experiment demonstrated that S. moorei increased H2S production by F. nucleatum (p < 0.05, ANOVA and Tukey's test). CONCLUSION: The increased amount of S. moorei in saliva, and its coexistence with F. nucleatum and T. forsythia, seemed to be responsible for increased oral hydrogen sulfide in the healthy male stressed subjects.