Euphorbia factor L3 ameliorates rheumatoid arthritis by suppressing the inflammatory response by targeting Rac family small GTPase 1

Anti-Inflammatory and Cytotoxic Compounds Isolated from Plants of Euphorbia Genus

Euphorbia is a large genus of the Euphorbiaceae family. Around 250 species of the Euphorbia genus have been studied chemically and pharmacologically; different compounds have been isolated from these species, especially diterpenes and triterpenes. Several reports show that several species have anti-inflammatory activity, which can be attributed to the presence of diterpenes, such as abietanes, ingenanes, and lathyranes. In addition, it was found that some diterpenes isolated from different Euphorbia species have anti-cancer activity. In this review, we included compounds isolated from species of the Euphorbia genus with anti-inflammatory or cytotoxic effects published from 2018 to September 2023. The databases used for this review were Science Direct, Scopus, PubMed, Springer, and Google Scholar, using the keywords Euphorbia with anti-inflammatory or cytotoxic activity. In this review, 68 studies were collected and analyzed regarding the anti-inflammatory and anti-cancer activities of 264 compounds obtained from 36 species of the Euphorbia genus. The compounds included in this review are terpenes (95%), of which 68% are diterpenes, especially of the types ingenanes, abietanes, and triterpenes (approximately 15%).

Exploring the causal association of rheumatoid arthritis with atrial fibrillation: a Mendelian randomization study

BACKGROUND

It has been proved that rheumatoid arthritis (RA) patients have high incidence of atrial fibrillation (AF). Nevertheless, whether they have causal relevance is uncertain. This study aimed to explore and verify the authenticity of causal relationship between RA and AF using Mendelian randomization (MR).

METHODS

The genome-wide association study (GWAS) summary data from Biobank Japan Project (BBJ) (RA, 4199 cases and 208,254 controls) were regarded as exposure data and the GWAS data from European Bio-informatics Institute database (EBI) (AF, 15,979 cases and 102,776 controls) as outcome data. The causal effect was appraised by the inverse variance weighted (IVW) method, MR-Egger regression, and weighted median estimator. MR-robust adjusted profile score (MR-RAPS) method was delivered to examine the robustness of causal relationship and MR Pleiotropy Residual Sum and Outlier (MR-PRESSO) method to control horizontal (directional) pleiotropy.

RESULTS

The results indicated that RA increased the risk of AF (IVW, the odds ratio (OR) = 1.060; 95% confidence interval (CI), 1.028 to 1.092; p = 1.411 × 10-4; weighted median, OR = 1.046, 95% CI, 1.002 to 1.093, p = 0.047). The MR analysis also showed this causal effect through all four IVW methods with various statistical algorithms. Both MR-RAPS and MR-PRESSO supported the causality of RA and AF. Also, the MR-PRESSO result indicated the absence of apparent pleiotropy.

CONCLUSION

There is a causal association between RA and AF. RA patients are genetically more vulnerable to AF. This study may contribute to further exploring early clinical prevention and fundamental mechanism of AF in patients with RA. Key Points • We provided some genetic evidence for the causal link between rheumatoid arthritis (RA) and atrial fibrillation (AF) with multiple Mendelian randomization (MR) methods. • RA patients were genetically more vulnerable to AF. • This study partly shed light on latent fundamental mechanisms underlying RA-induced AF and inspired future studies on RA-AF relationship.

Anti-inflammatory effects of naringenin 8-sulphonate from Parinari excelsa Sabine stem bark and its semi-synthetic derivatives

The inflammatory response is a vital mechanism for repairing damage induced by aberrant health states or external insults; however, persistent activation can be linked to numerous chronic diseases. The nuclear factor kappa β (NF-κB) inflammatory pathway and its associated mediators have emerged as critical targets for therapeutic interventions aimed at modulating inflammation, necessitating ongoing drug development. Previous studies have reported the inhibitory effect of a hydroethanol extract derived from Parinari excelsa Sabine (Chrysobalanaceae) on tumour necrosis factor-alpha (TNF-α), but the phytoconstituents and mechanisms of action remained elusive. The primary objective of this study was to elucidate the phytochemical composition of P. excelsa stem bark and its role in the mechanisms underpinning its biological activity. Two compounds were detected via HPLC-DAD-ESI(Ion Trap)-MS2 analysis. The predominant compound was isolated and identified as naringenin-8-sulphonate (1), while the identity of the second compound (compound 2) could not be determined. Both compound 1 and the extract were assessed for anti-inflammatory properties using a cell-based inflammation model, in which THP-1-derived macrophages were stimulated with LPS to examine the treatments' effects on various stages of the NF-κB pathway. Compound 1, whose biological activity is reported here for the first time, demonstrated inhibition of NF-κB activity, reduction in interleukin 6 (IL-6), TNF-α, and interleukin 1 beta (IL-1β) production, as well as a decrease in p65 nuclear translocation in THP-1 cells, thus highlighting the potential role of sulphur substituents in the activity of naringenin (3). To explore the influence of sulphation on the anti-inflammatory properties of naringenin derivatives, we synthesized naringenin-4'-O-sulphate (4) and naringenin-7-O-sulphate (5) and evaluated their anti-inflammatory effects. Naringenin derivatives 4 and 5 did not display potent anti-inflammatory activities; however, compound 4 reduced IL-1β production, and compound 5 diminished p65 translocation, with both exhibiting the capacity to inhibit TNF-α and IL-6 production. Collectively, the findings demonstrated that the P. excelsa extract was more efficacious than all tested compounds, while providing insights into the role of sulphation in the anti-inflammatory activity of naringenin derivatives.

Rac1 as a Target to Treat Dysfunctions and Cancer of the Bladder

Bladder pathologies, very common in the aged population, have a considerable negative impact on quality of life. Novel targets are needed to design drugs and combinations to treat diseases such as overactive bladder and bladder cancers. A promising new target is the ubiquitous Rho GTPase Rac1, frequently dysregulated and overexpressed in bladder pathologies. We have analyzed the roles of Rac1 in different bladder pathologies, including bacterial infections, diabetes-induced bladder dysfunctions and bladder cancers. The contribution of the Rac1 protein to tumorigenesis, tumor progression, epithelial-mesenchymal transition of bladder cancer cells and their metastasis has been analyzed. Small molecules selectively targeting Rac1 have been discovered or designed, and two of them—NSC23766 and EHT 1864—have revealed activities against bladder cancer. Their mode of interaction with Rac1, at the GTP binding site or the guanine nucleotide exchange factors (GEF) interaction site, is discussed. Our analysis underlines the possibility of targeting Rac1 with small molecules with the objective to combat bladder dysfunctions and to reduce lower urinary tract symptoms. Finally, the interest of a Rac1 inhibitor to treat advanced chemoresistance prostate cancer, while reducing the risk of associated bladder dysfunction, is discussed. There is hope for a better management of bladder pathologies via Rac1-targeted approaches.