Amelioration of melittin on adjuvant-induced rheumatoid arthritis: Integrated transcriptome and metabolome.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disease lacking a definitive cure. Although conventional treatments such as dexamethasone and methotrexate are prevalent, their usage is constrained by potential adverse effects. Melittin (MLT) has emerged as a promising natural anti-rheumatic drug; however, studies focusing on the role of MLT in modulating the expression and metabolism of RA-related genes are scarce. METHOD: Arthritis was induced in rats using Complete Freund's Adjuvant (CFA), followed by MLT injections for treatment. Post-treatment, the inflammatory status of each group was assessed, and the mechanistic underpinnings of MLT's ameliorative effects on RA were elucidated through transcriptomic and metabolomic analyses. Additionally, this study conducted qRT-PCR validation of key therapeutic genes and characterized the molecular docking interactions of MLT with key receptor proteins (TNF-α and IL-1ß) using the AutoDock Vina software. RESULT: MLT significantly diminished redness and swelling in affected joints, ameliorated inflammatory cell infiltration, and mitigated joint damage. Integration of transcriptomic and metabolomic data revealed that MLT predominantly regulated the transcription levels of pathways and genes related to cytokines and immune responses, and the metabolic biomarkers of Sphingomyelin, fatty acid, and flavonoid. qRT-PCR confirmed MLT's downregulation of inflammation-related genes such as Il6, Jak2, Stat3, and Ptx3. Molecular docking simulations demonstrated the stable binding of MLT to TNF-α and IL-1ß. CONCLUSION: MLT demonstrated significant efficacy in alleviating RA. This study provides a comprehensive summary of MLT's impact on gene expression and metabolic processes associated with RA.

Melittin promotes dexamethasone in the treatment of adjuvant rheumatoid arthritis in rats.

Background: Rheumatoid arthritis (RA) is an erosive-destructive inflammation of the joints, and the chronic, long-term stiffness and deformation induced by RA are some of the symptoms of arthritis that are difficult to treat. Dexamethasone (DEX) and melittin (MLT) are two interesting anti-inflammatory substances, both of which possess anti-inflammatory effects exerted through the suppression of the immune system. The purpose of this study was to explore the role of MLT in the treatment of RA by DEX as well as to clarify the influence of MLT on the efficacy and side effects of DEX. Method: The rats were injected with Complete Freund's Adjuvant (CFA) to induce arthritis, followed by treatment with different doses of DEX and/or MLT. The relevant indexes of paw inflammation were determined, and the appetite, growth status, arthritis status, cytokine levels, and organ coefficient of the rats were evaluated. In addition, the paraffin sections of the joint tissues were prepared to analyze the pathological changes. Result: DEX exhibited side effects, notably hindering feed intake and growth, and inducing immune organ lesions in the rats. MLT significantly reduced the side effects of DEX and promoted its efficacy. DEX in combination with MLT demonstrated a synergistic efficacy in RA treatment, showing advantages in detumescence reduction, pro-inflammatory cytokine inhibition, and joint internal pathological improvement. Conclusion: Thus, MLT promoted the efficacy of DEX in adjuvant RA treatment in rats, offering an approach to reduce the use dosage and side effects of DEX.

Exploring potential network pharmacology-and molecular docking-based mechanism of melittin in treating rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is a type of difficult-to-cure arthralgia with a worldwide prevalence. It severely affects people's living standards. For a long time, bee venom has been used to treat RA and has shown good results. Melittin is the main active component of bee venom used for RA treatment, but the molecular mechanism of melittin in RA treatments remains unclear. METHODS: Potential melittin and RA targets were obtained from relevant databases, and common targets of melittin and RA were screened. The STRING database was used to build the PPI network and screen the core targets after visualization. The core targets were enriched by Gene Ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway. Finally, the binding of melittin to target proteins was evaluated through simulated molecular docking, which verified the reliability of the prediction results of network pharmacology. RESULTS: In total, 138 melittin targets and 5795 RA targets were obtained from relevant databases, and 90 common targets were obtained through intersection. Eighteen core targets, such as STAT3, AKT1, tumor necrosis factor, and JUN, were screened out. Enrichment analysis results suggested that melittin plays an anti-RA role mainly through tumor necrosis factor, interleukin-17, toll-like receptors, and advanced glycation end products-RAGE signaling pathways, and pathogenic bacterial infection. Molecular docking results suggested that melittin has good docking activity with core target proteins. CONCLUSION: RA treatment with melittin is the result of a multi-target and multi-pathway interaction. This study offers a theoretical basis and scientific evidence for further exploring melittin in RA therapy.

Co-expression of Erns and E2 genes of classical swine fever virus by replication-defective recombinant adenovirus completely protects pigs against virulent challenge with classical swine fever virus.

The objective of this study was to construct a recombinant adenovirus for future CSFV vaccines used in the pig industry for the reduction of losses involved in CSF outbreaks. The Erns and E2 genes of classical swine fever virus (CSFV), which encode the two main protective glycoproteins from the "Shimen" strain of CSFV, were combined and inserted into the replication-defective human adenovirus type-5 and named the rAd-Erns-E2. Nine pigs were randomly assigned to three treatment groups (three pigs in each group) including the rAd-Erns-E2, hAd-CMV control and DMEM control. Intramuscular vaccination with 2×10(6) TCID(50) of the rAd-Erns-E2 was administered two times with an interval of 21 days. At 42 days post inoculation, pigs in all groups were challenged with a lethal dose of 1×10(3) TCID(50) CSFV "Shimen" strain. Observation of clinical signs was made and the existence of CSFV RNA was detected. Animals in the hAd-CMV and DMEM groups showed severe clinical CSF symptoms and were euthanized from 7 to 10 days after the challenge. However, no adverse clinical CSF signs were observed in vaccinated pigs after the administration of rAd-Erns-E2 and even after CSFV challenge. Neither CSFV RNA nor pathological changes were detected in the tissues of interest of the above vaccinated pigs. These results implied that the recombination adenovirus carrying the Erns-E2 genes could be used to prevent swine from classical swine fever.