Anti-Inflammatory Derivatives with Dual Mechanism of Action from the Metabolomic Screening of Poincianella pluviosa

Susceptibility of Staphylococcus aureus to Anti-Inflammatory Drugs with a Focus on the Combinatory Effect of Celecoxib with Oxacillin In Vitro

Musculoskeletal infections (MIs) are among the most difficult-to-treat staphylococcal diseases due to antibiotic resistance. This has encouraged the development of innovative strategies, such as combination therapy, to combat MI. The aim of this study was to investigate the in vitro antistaphylococcal activity of anti-inflammatory drugs and the combined antimicrobial effect of celecoxib and oxacillin. The minimum inhibitory concentrations (MICs) of 17 anti-inflammatory drugs against standard strains and clinical isolates of S. aureus, including methicillin-resistant strains (MRSAs), were determined using the broth microdilution method. The fractional inhibitory concentration indices (FICIs) were evaluated using checkerboard assays. Celecoxib produced the most potent antistaphylococcal effect against all tested strains (MICs ranging from 32 to 64 mg/L), followed by that of diacerein against MRSA3 and MRSA ATCC 33592 (MIC 64 mg/L). Several synergistic effects were observed against the tested S. aureus strains, including MRSA (FICI ranging from 0.087 to 0.471). The strongest synergistic interaction (FICI 0.087) was against MRSA ATCC 33592 at a celecoxib concentration of 2 mg/L, with a 19-fold oxacillin MIC reduction (from 512 to 26.888 mg/L). This is the first report on the combined antistaphylococcal effect of celecoxib and oxacillin. These findings suggest celecoxib and its combination with oxacillin as perspective agents for research focused on the development of novel therapies for MI caused by S. aureus. This study further indicates that celecoxib could resensitize certain MRSA strains, in some cases, to be susceptible to β-lactams (e.g., oxacillin) that were not previously tested. It is essential to mention that the in vitro concentrations of anti-inflammatory drugs are higher than those typically obtained in patients. Therefore, an alternative option for its administration could be the use of a drug delivery system for the controlled slow release from an implant at the infection site.

Phytochemical investigation of Nigrospora zimmermanii isolated from Poincianella pluviosa (Sibipiruna): metabolites characterisation and screening for anti-inflammatory activity

Endophytic fungi residing symbiotically in plant tissues are promising sources of bioactive natural products. This study explored the anti-inflammatory potential of an endophytic fungus isolated from the Brazilian medicinal plant Poincianella pluviosa (Sibipiruna). The extract from the endophyte FPD13 exhibited potential ex vivo anti-inflammatory effects by inhibiting prostaglandin E2 (PGE2) release by 75.22%. Phytochemical analysis using High-Performance Liquid Chromatography (HPLC), Nuclear Magnetic Resonance (NMR), and Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS) enabled the isolation and identification of three compounds, including the macrolide Nigrosporolide, the phenyl-propanol Tyrosol, and the terpene Decarestrictine A. Morphological characteristics and Internal Transcribed Spacers region (ITS) sequencing classified fungus FPD13 as Nigrospora zimmermanii. The results reveal the anti-inflammatory potential and chemical diversity of P. pluviosa endophytes, warranting further investigation into the bioactivity and structure elucidation of their bioactive metabolites.

Protective effect of Lizhong Pill on nonsteroidal anti-inflammatory drug-induced gastric mucosal injury in rats: Possible involvement of TNF and IL-17 signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional Chinese medicine formula Lizhong Pill (LZP) and its herbal constituents are frequently utilized in Asian (China, Saudi Arabia, India, Japan, etc.) and some European (Russia, Sweden, UK, etc.) nations to treat various gastrointestinal ailments.

AIM OF THE STUDY

This study aimed to investigate the protective impact and potential mechanism of LZP against indomethacin (IND)-induced gastric mucosal injury in rats.

MATERIAL AND METHODS

Using a biochemical kit, we investigated the levels of superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) in rat serum, as well as pepsin in rat stomach tissue, using an IND-induced rat model of gastric mucosal injury. Various imaging tools, including HE staining, scanning electron microscopy (SEM), and transmission electron microscopy (TEM), were used to examine the gastric mucosa's surface morphology and ultrastructure. Furthermore, molecular docking was employed to predict the binding capacity of the primary bioactive components of LZP to the critical molecular protein targets in the IL-17 and TNF signaling pathways. At the same time, immunofluorescence was used to determine the protein expressions of CASP3, VCAM1, MAPK15, MMP3, IL-17RA, and TNFR1.

RESULTS

The present study demonstrates that LZP (3.75 and 7.50 g/kg) significantly reduces the gastric mucosal injury index induced by IND. This effect is evidenced by the improved morphology, surface, and structure of the gastric mucosa, as determined by HE, SEM, and TEM findings. Additionally, 3.75 and 7.50 g/kg LZP intervention significantly increased SOD and CAT contents and inhibited pepsin and GST activities. Molecular docking analysis revealed that the small molecular components of LZP can bind spontaneously to crucial proteins involved in the IL-17 and TNF signaling pathways, including MAPK15, MMP3, VCAM1, and CASP3. The immunofluorescence findings proved that LZP (3.75 and 7.50 g/kg) can inhibit the protein expressions of MAPK15, MMP3, VCAM1, CASP3, IL-17RA, and TNFR1.

CONCLUSIONS

Our investigation findings demonstrate that LZP can potentially ameliorate IND-induced damage to the gastric mucosa by inhibiting IL-17 and TNF signaling pathways. These results offer encouraging support for using alternative medicine to manage drug-induced gastric mucosal injury.

Ex vivo inhibition of PGE2 formation in human blood by four bicyclico [3.2.1] octane neolignans isolated from Aniba firmula bark, two with unusual structural pattern

The phytochemical investigation of the stem bark crude extract of Aniba firmula (Lauraceae) led to the isolation of undescribed bicyclic [3.2.1] octane neolignans, 1 and 2, characterized by unusual bicyclic patterns and two other known bicyclic neolignans 3 and 4. Anti-inflammatory bicyclic [3.2.1] octane neolignans metabolites were previously reported in the literature, and the A. firmula stands out in the Lauraceae family as a source of potentially bioactive compounds. Thus, herein the anti-inflammatory potential of four isolated compounds from A. firmula was accessed via an ex vivo anti-inflammatory model that included plasmatic quantification of the prostaglandin E2 (PGE2) inflammatory mediator. Compounds 2 and 3 exhibited significant anti-inflammatory activity by inhibiting the production of PGE2 in plasma samples, thus by interference with the cyclooxygenase (COX) inflammatory pathway. Therefore, these findings demonstrate that the bicyclic octane neolignan classes [3.2.1] can present anti-inflammatory potential.

Potential anti-inflammatory biomarkers from Myrtaceae essential oils revealed by untargeted metabolomics

Many species from Myrtaceae have traditionally been used in traditional medicine as anti-inflammatory, antimicrobial, antidiarrheal, antioxidant and antirheumatic, besides in blood cholesterol reduction. In the present work, the anti-inflammatory activity of essential oils from eighteen Myrtaceae spp. were evaluated according to their ex-vivo anti-inflammatory activity in human blood, and the corresponding biomarkers were determined using untargeted metabolomics data and multivariate data analysis. From these studied species, six displayed anti-inflammatory activity with percentage rates of inhibition of PGE2 release above 70%. Caryophyllene oxide (1), humulene epoxide II (2), β-selinene (3), α-amorphene (4), α-selinene (5), germacrene A (6), β-bisabolene (7), α-muurolene (8), α-humulene (9), β-gurjunene (10), myrcene (11), β-elemene (12), α-cadinol (13), α-copaene (14), E-nerolidol (15) and ledol (16) were annotated as potential anti-inflammatory biomarkers. The results obtained in this study point to essential oils from species of the Myrtaceae family as a rich source of anti-inflammatory agents.

A metabolomics-based analysis of the metabolic pathways associated with the regulation of branched-chain amino acids in rats fed a high-fructose diet

Previous studies have shown that the elevated levels of circulating branched-chain amino acids (BCAAs) are associated with the development of insulin resistance and its complications, including obesity, type 2 diabetes, cardiovascular disease and some cancers. However, animal models that can mimic the metabolic state of chronically elevated BCAAs in humans are rare. Therefore, the aim of this study was to establish the above animal model and analyse the metabolic changes associated with high BCAA levels. Sixteen 8-week-old Sprague-Dawley (SD) rats were randomly divided into two groups and given either a high fructose diet or a normal diet. BCAA levels as well as blood glucose and lipid levels were measured at different time points of feeding. The mRNA expression levels of two key enzymes of BCAA catabolism, ACAD (acyl-CoA dehydrogenase) and BCKDH (branched-chain α-keto acid dehydrogenase), were measured by qPCR, and the protein expression levels of these two enzymes were analysed by immunohistochemistry. Finally, the metabolite expression differences between the two groups were analysed by Q300 metabolomics technology. Our study confirms that defects in the catabolic pathways of BCAAs lead to increased levels of circulating BCAAs, resulting in disorders of glucose and lipid metabolism characterized by insulin resistance by affecting metabolic pathways associated with amino acids and bile acids.

Control of fungal spoilage in strawberries using crude plant extracts against the fungus Botrytis cinerea

The study evaluated the conservation of strawberries treated with crude plant extracts (barbatimão, sibipiruna, guarana, and catuaba) against fungal deterioration and physicochemical characteristics. MIC of 0.125; 0.0156; 0.25 and 0.0312 g/mL were found for barbatimão, sibipiruna, guaraná and catuaba, respectively, against B. cinerea. Treated samples showed no fungal deterioration during 11 days. Analyzes of weight loss, soluble solids, titratable acidity, and pH variation were performed. Sibipiruna showed lower values ​​of mass loss, and the greatest occurred for the catuaba extract. Barbatimão did not change soluble solids and stood out with catuaba in the color parameters L and a*. Small changes in pH were observed with time. Soluble solids maintained values ​​between 6.47 oBrix and 9.90 oBrix for catuaba and sibipiruna extracts at zero and six days. Principal component analysis did not show a strong correlation between the variables. The extracts become alternatives for strawberry conservation, increasing conservation and maintaining physicochemical characteristics.

Natural Products Drug Discovery: On Silica or In-Silico?

Natural products have been the most important source for drug development throughout the human history. Over time, the formulation of drugs has evolved from crude drugs to refined chemicals. In modern drug discovery, conventional natural products lead-finding usually uses a top-down approach, namely bio-guided fractionation. In this approach, the crude extracts are separated by chromatography and resulting fractions are tested for activity. Subsequently, active fractions are further refined until a single active compound is obtained. However, this is a painstakingly slow and expensive process. Among the alternatives that have been developed to improve this situation, metabolomics has proved to yield interesting results having been applied successfully to drug discovery in the last two decades. The metabolomics-based approach in lead-finding comprises two steps: (1) in-depth chemical profiling of target samples, e.g. plant extracts, and bioactivity assessment, (2) correlation of the chemical and biological data by chemometrics. In the first step of this approach, the target samples are chemically profiled in an untargeted manner to detect as many compounds as possible. So far, NMR spectroscopy, LC-MS, GC-MS, and MS/MS spectrometry are the most common profiling tools. The profile data are correlated with the biological activity with the help of various chemometric methods such as multivariate data analysis. This in-silico analysis has a high potential to replace or complement conventional on-silica bioassay-guided fractionation as it will greatly reduce the number of bioassays, and thus time and costs. Moreover, it may reveal synergistic mechanisms, when present, something for which the classical top-down approach is clearly not suited. This chapter aims to give an overview of successful approaches based on the application of chemical profiling with chemometrics in natural products drug discovery.

Anti-Inflammatory Markers of Hops Cultivars (Humulus lupulus L.) Evaluated by Untargeted Metabolomics Strategy

Hops (Humulus lupulus L.) are edible flowers commonly used to add flavour and aroma to beer, besides they have rich chemical diversity and medicinal potential. In this work, an ex vivo anti-inflammatory assay via the LPS-induced signalling pathway and metabolomics approaches were performed to evaluate the ability of hops to inhibit the production of prostaglandin E2 (PGE2) inflammatory mediator and analyze which metabolites produced by the nine different hop cultivars are potential anti-inflammatory markers. Columbus, Chinook and Hallertau Mittelfrüh hop cultivars yielded extracts with PGE2 release inhibition rates of 86.7, 92.5 and 73.5 %, respectively. According to the multivariate statistical analysis, the majority of the metabolites correlated with the activity were prenylated phloroglucinol and phenolic homologs. These results suggest promissory anti-inflammatory hop metabolites.

Antifungal Combination of Ethyl Acetate Extract of Poincianella pluviosa (DC.) L. P. Queiros Stem Bark With Amphotericin B in Cryptococcus neoformans

Cryptococcus neoformans is the leading cause of cryptococcosis, an invasive and potentially fatal infectious disease. Therapeutic failures are due to the increase in antifungal resistance, the adverse effects of drugs, and the unavailability of therapeutic regimens in low-income countries, which limit the treatment of cryptococcosis, increasing the morbidity and mortality associated with these infections. Thus, new antifungal drugs and innovative strategies for the cryptococcosis treatment are urgently needed. The aim of the present study was to evaluate the effect of ethyl acetate fraction (EAF) of Poincianella pluviosa stem bark on planktonic and biofilm mode of growth of C. neoformans. Furthermore, the interaction between the EAF and amphotericin B (AmB) was evaluated in vitro and in Galleria mellonella infection model. Minimal inhibitory concentrations (MICs) of EAF ranged from 125.0 to >1,000.0 μg/ml and >1,000.0 μg/ml for planktonic and sessile cells, respectively. The combination between EAF and AmB exhibited a synergistic fungicidal activity toward C. neoformans, with a fractional inhibitory concentration index (FICI) ranging from 0.03 to 0.06 and 0.08 to 0.28 for planktonic and sessile cells, respectively. Microscopy analyses of planktonic C. neoformans cells treated with EAF, alone or combined with AmB, revealed morphological and ultrastructural alterations, including loss of integrity of the cell wall and cell membrane detachment, suggesting leakage of intracellular content, reduction of capsule size, and presence of vacuoles. Moreover, EAF alone or combined with AmB prolonged the survival rate of C. neoformans-infected G. mellonella larvae. These findings indicate that P. pluviosa may be an important source of new compounds that can be used as a fungus-specific adjuvant for the treatment of cryptococcosis.

Integrated multiplatform-based metabonomics and network analysis to explore the mechanism of Polygonum cuspidatum on hyperlipidemia

Hyperlipidemia is a major risk factor and pathological basis for cardiovascular diseases. Polygonum cuspidatum (HZ), a famous traditional Chinese medicine, is frequently used to treat hyperlipidemia. However, little is known about its underlying mechanism. Herein, an integrated approach combining multiplatform-based metabonomics and network analysis was adopted to elucidate the ameliorative mechanism of HZ on hyperlipidemia. The global metabolomic characters of HZ on hyperlipidemia were investigated by GC-MS and LC-MS based metabonomics. Significant metabonomic alterations were observed in hyperlipidemic group, which could be restored by HZ supplementation. Furthermore, the drug-ingredients-target-metabolic pathway network was constructed, and the result indicated that HZ exhibited hypolipidemic efficacy through resveratrol, polydatin, torachrysone-8-O-β-D-(6'-oxayl)-glucoside, physciondiglucoside, (+)-catechin, β-sitosterol, quercetin, luteolin and physovenine acting on phospholipase A2, unspecific monooxygenase, arachidonate 15-lipoxygenase, aromatic-L-amino-acid decarboxylase, alcohol dehydrogenase and triacylglycerol lipase. In conclusion, this study explored potential mechanism of HZ on hyperlipidemia with the aid of the integrated approach combining multiplatform-based metabonomics and network analysis, which might provide a theoretical basis for the clinical application of HZ.

Confirmation of ethnopharmacological anti-inflammatory properties of Ocotea odorifera and determination of its main active compounds

ETHNOPHARMACOLOGICAL RELEVANCE

Ocotea odorifera (Vell.) Rohwer has been used in traditional medicine in the south of Brazil for the treatment of inflammatory-related conditions, such as rheumatism. However, there is not any scientific evidence for popular use.

AIMS OF THE STUDY

To investigate the O. odorifera anti-inflammatory potential and identification of the main active compounds through metabolomic approaches.

MATERIALS AND METHODS

In order to in vivo evaluate the inhibition of the main inflammatory pathways, the leaf decoction, leaf extract, its fractions and the essential oils from leaves and branches were submitted to the ear oedema and the neutrophils recruitment assays. The samples were chemically investigated by UHPLC-HRMS or GC-MS. The multivariate statistical analysis (PLS-DA) was used to determine the substances correlated with the anti-inflammatory properties.

RESULTS

The in vivo studies indicated a promissory anti-inflammatory effect on both oedema and neutrophil recruitment for some samples including the decoction; hydroethanolic, ethyl acetate, and chloroform fractions; and the essential oils. According to the PLS-DA, the S-(+)-reticuline was evidenced as one of the three compounds of the plant most correlated with both anti-inflammatory mechanisms. Thus, S-(+)-reticuline was isolated and the anti-inflammatory activity was confirmed. Moreover, for the first time, the dual inhibition of oedema and neutrophil recruitment was uncovered and reported. Another compound positively correlated with the anti-inflammatory activity is likely to be a new compound since zero hit on the comprehensive mass database were encountered. The compounds found in the essential oils also showed significant anti-inflammatory activity, and thus indeed the plant has different classes of active substances.

CONCLUSIONS

The decoction of O. odorifera and different fractions from its ethanolic extract demonstrated anti-inflammatory activity through dual inhibition of oedema and neutrophil recruitment. Thus, corroborating the popular medicinal use of the decoction of leaves from O. odorifera as an anti-inflammatory medicine. Besides, reticuline, one of the main active compounds, was isolated and proved to display the dual mechanism of action, indicating the O. odorifera as a promising source of active compounds for the treatment of inflammatory conditions.

Potential Therapeutic Anti-Inflammatory and Immunomodulatory Effects of Dihydroflavones, Flavones, and Flavonols

Systemic inflammation, circulating immune cell activation, and endothelial cell damage play a critical role in vascular pathogenesis. Flavonoids have shown anti-inflammatory effects. In this study, we investigated the effects of different flavonoids on the production of pro-inflammatory interleukin (IL) 1β, 6, and 8, and tumor necrosis factor α (TNF-α), in peripheral blood cells. Methods: We studied the whole blood from 36 healthy donors. Lipopolysaccharide (LPS)-stimulated (0.5 μg/mL) whole-blood aliquots were incubated in the presence or absence of different concentrations of quercetin, rutin, naringenin, naringin, diosmetin, and diosmin for 6 h. Cultures were centrifuged and the supernatant was collected in order to measure IL-1β, TNF-α, IL-6, and IL-8 production using specific immunoassay techniques. This production was significantly inhibited by quercetin, naringenin, naringin, and diosmetin, but in no case by rutin or diosmin. Flavonoids exert different effects, maybe due to the differences between aglycons and glucosides present in their chemical structures. However, these studies suggest that quercetin, naringenin, naringin, and diosmetin could have a potential therapeutic effect in the inflammatory process of cardiovascular disease.