Synthesis and anti-inflammatory activity evaluation of NO-releasing furoxan/1,2,4-triazole hybrid derivatives

Redesigning Ibuprofen for Improved Oral Delivery and Reduced Side Effects

Ibuprofen (IBP) is one of the most widely used nonsteroidal anti-inflammatory drugs (NSAIDs). Being well-known for its efficacy, long history of use, and reduced adverse events compared to other NSAIDs, IBP is authorized as an analgesic and antipyretic drug. IBP's mechanism of action consists of inhibiting cyclooxygenases, which are crucial oxidoreductases in prostaglandin synthesis and generation of inflammation and pain. However, despite being effective and relatively safe, IBP can still induce a dose-dependent toxicity which manifests mainly in the gastrointestinal system as ulcerations and altered mucosal blood flow and cytotoxicity characterized by mitochondrial dysfunction and increased membrane permeability in enterocytes and hepatocytes. Therefore, ongoing research is performed to improve the IBP's activity and treatment outcome, and one way to achieve such improvements is through reducing IBP's toxicity by designing less harmful but still effective novel IBP conjugates. The aim of this review is to summarize the latest achievements with IBP conjugation techniques that created such valuable IBP formulations less toxic than but as effective as the parent drug.

The anti-inflammatory effects of saponins from natural herbs

Inflammation is a protective mechanism that also starts the healing process. However, inflammatory reaction may cause severe tissue damage. The increased influx of phagocytic leukocytes may produce excessive amount of reactive oxygen species, which leads to additional cell injury. Inflammatory response activates the leukocytes and thus induces tissue damage and prolongs inflammation. The inflammation-induced activation of the complement system may also contribute to cell injury. Non-steroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids are chief agents for treating inflammation associated with the diseases. However, the unwanted side effects of NSAIDs (e.g., gastrointestinal disturbances, skin reactions, adverse renal effects, cardiovascular side effects) and glucocorticoids (e.g., suppression of immune system, Cushing's syndrome, osteoporosis, hyperglycemia) limit their use in patients. Natural herbs are important sources of anti-inflammatory drugs. The ingredients extracted from natural herbs display anti-inflammatory effects to work through multiple pathways with lower risk of adverse reaction. At present, the main anti-inflammatory natural agents include saponins, flavonoids, alkaloids, polysaccharides, and so on. The present article will review the anti-inflammatory effects of saponins including escin, ginsenosides, glycyrrhizin, astragaloside, Panax notoginseng saponins, saikosaponin, platycodin, timosaponin, ophiopogonin D, dioscin, senegenin.

Design, synthesis, and evaluation of carboxylic acid-substituted celecoxib isosteres as potential anti-inflammatory agents

A library comprising twenty-four isosteric derivatives of celecoxib substituted with carboxylic acid (labeled as 5a-5x), was synthesized and characterized through 1H NMR, 13C NMR, HRMS, and elemental analysis. Molecular docking studies revealed that all compounds successfully docked into the binding pocket of COX-2, and the introduction of carboxyl group enhances the interaction between the derivatives and COX-2. The compounds were further evaluated for cell toxicity, and in vitro anti-inflammatory activity. Notably, compound 5l exhibited significant inhibition of both COX-2 and NO release in vitro in comparison to the standard compound, displaying the highest selectivity towards the COX-2 enzyme (SI = 295.9) in comparison to celecoxib (SI = 261.3). 5l also exhibited the most potent anti-inflammatory activity and safety (ulcer index = 5.2) in vivo comparable to celecoxib at the same concentration. Through the molecular modeling and dynamics analysis, it was observed that compound 5l effectively stabilized within the active binding site of COX-2 through strong hydrogen bond interactions, and through the ADMET studies investigated the physiochemical properties and drug-likeliness behavior of compound 5l. In conclusion, compound 5l demonstrated to be a potential selective COX-2 anti-inflammatory candidate with reduced gastrointestinal risks.

Synthesis and Biological Evaluation of Isoaurone Derivatives as Anti-inflammatory Agents

Twenty-eight isoaurone derivatives with 1,2,4-triazole moieties were synthesized using a fragment-based design strategy, and their anti-inflammatory activity was investigated. The anti-inflammatory effect of the most active derivative, 14e (41.82 %), was dose-dependent and higher than the values for celecoxib (31.82 %). Compound 14e was almost non-toxic and inhibited different concentrations of nitric oxide (NO). The western blotting results demonstrated that cyclooxygenase-2 (COX-2) expression was elevated when the macrophages were exclusively treated with LPS. However, compound 14e effectively suppressed the LPS-induced COX-2 upregulation. Subsequent investigation revealed that 14e is a promising compound capable of inhibiting the downstream signaling of COX-2. With the above interesting biological profile, molecular 14e could be a promising lead to develop novel anti-inflammatory agents.

Integrating network pharmacology and transcriptomics to study the potential mechanism of Jingzhi Niuhuang Jiedu tablet in rats with accumulation of heat in the lungs and stomach

ETHNOPHARMACOLOGICAL RELEVANCE

Accumulation of heat in the lungs and stomach (AHLS) is an important syndrome within the realm of traditional Chinese medicine (TCM). It is the fundamental reason behind numerous illnesses, including mouth ulcers, dermatological conditions, acne, and pharyngitis. Jingzhi Niuhuang Jiedu tablet (JN) serves as the representative prescription for treatment of AHLS clinically. However, the effective components and mechanism of JN's impact on AHLS remain unexplored.

AIM OF THE STUDY

The objective of this research was to analyze the effective components of JN and investigate the therapeutic effect and potential mechanism of JN on AHLS.

MATERIALS AND METHODS

The effective compounds of JN extract were analyzed and identified using UHPLC-Q-Exactive/HRMS. Utilizing network pharmacology to investigate JN's multi-target, multi-pathway process in treating AHLS. Subsequently, anti-inflammatory activities of JN extract were evaluated in the RAW264.7 cells stimulated by lipopolysaccharide (LPS). In addition, a rat AHLS model induced by LPS and dried ginger was established. Pathological changes in rat lung and stomach tissues observed by HE staining and Masson's trichrome staining. Additionally, the expression of TNF-α, IL-6, and IL-1β in bronchoalveolar lavage fluid (BALF) was identified through the ELISA assay. For a deeper understanding of how JN might affect AHLS, transcriptomics was utilized to examine differential genes and their underlying mechanisms. Concurrently, techniques like quantitative polymerase chain reaction (q-PCR), immunofluorescence, and western blotting (WB) were employed to confirm various mRNA and protein expression, including Il17ra, Il17re, IL-17A, IL-1β, IL-6, PPARγ, PGC1-α and UCP1.

RESULTS

We identified 178 potential effective components in the JN extract. Network pharmacology analysis showed that the 144 components in JN act on 200 key targets for the treatment of AHLS by suppressing inflammation, regulating energy metabolism, and gastric function. In addition, JN suppressed the LPS-stimulated generation of NO, TNF-α, IL-1β, and IL-6 in RAW264.7 cells. And JN treatment effectively alleviated lung and stomach injury and reduced inflammation in rats. Analysis of RNA-seq from lung tissues revealed JN's substantial control over crucial genes in the IL-17 signaling pathway, including Il1b and Il17ra. Likewise, RNA sequencing of stomach tissues revealed that JN markedly decreased crucial genes in the Thermogenesis pathway, including Ppargc1a and Ppara. Additional experimental findings confirmed that treatment with JN significantly reduced the expression levels of mRNA (Il17ra, Il17re, Il1b, Ppargc1a and Ucp1), and the expression levels of protein (IL-17A, IL-1β, IL-6, PPARγ, PGC1-α and UCP1).

CONCLUSION

This study not only analyzes the effective components of JN but also reveals that JN could effectively ameliorate AHLS by inhibiting IL-17 signaling pathway and Thermogenesis pathway, which provides evidence for subsequent clinical studies and drug development.

In vitro and In vivo Activity of a New N-Oxide Derivative for Acne Vulgaris Treatment

INTRODUCTION

Furoxan and benzofuroxan are compounds containing an N-oxide function, known for their diverse pharmacological properties, including antimicrobial and antiinflammatory effects. This study aimed to investigate these activities using an in-house library of N-oxide compounds.

METHOD

Twenty compounds were tested against both Gram-positive and Gram-negative bacteria, including Cutibacterium acnes (C. acnes), a microorganism implicated in the development of acne vulgaris. One compound, (E)-4-(3-((2-(3-hydroxybenzoyl)hydrazone)methyl)phenoxy)-3- (phenylsulfonyl)-1,2,5-oxadiazol-2-N-oxide (compound 15), exhibited selective antimicrobial activity against C. acnes, with a Minimum Inhibitory Concentration (MIC) value of 2 μg/mL. Indirect measurement of Nitric Oxide (NO) release showed that compound 15 and isosorbide dinitrate, when treated with L-cysteine, produced nitrite levels of 20.1% and 9.95%, respectively. Using a NO scavenger (PTIO) in combination with compound 15 in a culture of C. acnes resulted in reduced antimicrobial activity, indicating that NO release is part of its mechanism of action. Cytotoxicity assessments using murine macrophages showed cellular viability above 70% at concentrations up to 0.78 μg/mL.

RESULTS

Measurements of Interleukin-1 beta (IL1-β) and Tumor Necrosis Factor-alpha (TNF-α) indicated that compound 15 did not reduce the levels of these pro-inflammatory cytokines. Sustained NO production by inducible Nitric Oxide Synthase (iNOS) in macrophages or neutrophils has been found to be involved in the inflammatory process in acne vulgaris and lead to toxicity in surrounding tissues. Nitrite levels in the supernatant of murine macrophages were found to be decreased at a concentration of 0.78 μg/mL of compound 15, indicating an anti-inflammatory effect. In vivo studies were conducted using Balb/c nude mice inoculated subcutaneously with C. acnes. Cream and gel formulations of compound 15 were applied to treat the animals, along with commercially available anti-acne drugs, for 14 days. Animals treated with a cream base containing 5% of compound 15 exhibited less acanthosis with mild inflammatory infiltration compared to other groups, highlighting its anti-inflammatory properties.

CONCLUSION

Similar results were observed in the benzoyl peroxide group, demonstrating that compound 15 presented comparable anti-inflammatory activity to the FDA-approved drug. These promising results suggest that compound 15 has a dual mechanism of action, with selective antimicrobial activity against C. acnes and notable anti-inflammatory properties, making it a potential prototype for developing new treatments for acne vulgaris.

Search for New Compounds with Anti-Inflammatory Activity Among 1,2,4-Triazole Derivatives

Compounds containing the 1,2,4-triazole moiety in their structure exhibit broad biological activities. Many of these compounds demonstrate anti-inflammatory activity in vitro through various mechanisms, such as inhibiting COX-1/COX-2 and LOX, modulating pro-inflammatory cytokine levels, or having effects on other specific enzymes. Some also display activities in vivo. In many publications, the activities of new 1,2,4-triazole-based compounds exceed those of the reference drugs, suggesting their promising potential as new therapeutic agents. This review of active 1,2,4-triazole derivatives with anti-inflammatory activity is based on literature published from 2015-2024.

Synthesis, physicochemical characterization, and investigation of anti-inflammatory activity of water-soluble PEGylated 1,2,4-Triazoles

A series of water-soluble PEGylated 1,2,4-triazoles 5-8 were successfully synthesized from methyl 5-(chloromethyl)-1-aryl-1H-1,2,4-triazole-3-carboxylates 1. All of the water-soluble PEGylated 1,2,4-triazoles were characterized by FT-IR and 1H NMR spectroscopy. The solubility, in vitro plasma stability, and anti-inflammatory activity were also determined and compared to original methyl 5-(halomethyl)-1-aryl-1H-1,2,4-triazole-3-carboxylates. For SAR study, all PEGylated 1,2,4-triazoles 5-8 performed potential anti-inflammatory activity on LPS-induced RAW 264.7 cells (IC50 = 3.42-7.81 μM). Moreover, the western blot result showed PEGylated 1,2,4-triazole 7d performed 5.43 and 2.37 folds inhibitory activity over iNOS and COX-2 expressions. On the other hand, the cell viability study revealed PEGylated 1,2,4-triazoles 7 and 8 with PEG molecular weight more than 600 presented better cell safety (cell viability > 95 %). Through the solubility and in vitro plasma stability studies, PEGylated 1,2,4-triazoles 7a-d exhibited higher hydrophilicity and prolonged 2.01 folds of half-life in compound 7d. Furthermore, the in vivo anti-inflammatory and gastric safety results indicated PEGylated 1,2,4-triazole 7d more effectively decreased the inflammatory response in edema and COX-2 expression and exhibited higher gastric safety than Indomethacin. Following the in vitro and in vivo study results, PEGylated 1,2,4-triazole 7d possessed favorable solubility, plasma stability features, safety, and significant anti-inflammatory activity to become the potential water-soluble anti-inflammatory candidate.