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.

Impact of Brood Cell Cocoons on Metal Accumulation and CYP450 Detoxification Gene Expression in Apis cerana cerana.

Honey bees play a critical role as pollinators. However, their reproduction success and survival face severe threats due to the deterioration of their living environment. Notably, environmental conditions during their preimaginal stage inside brood cells can influence their immune capabilities and overall health after emergence. During the in-cell developmental stage, workers are in close contact with cocoons, which can become a source of stress due to accumulated metals. To investigate this potential threat, experiments were conducted to examine the impact of cocoons in brood cells used to rear different generations on the metal content and detoxification gene expression levels in Apis cerana cerana. Our findings indicated significant differences in the layers, weight, base thickness, and metal contents like Cr, Cd, Pb, Mn, Ni, and As of cocoons in multi-generation brood cells compared to single-generation brood cells. These increases led to significant elevations in metal levels and upregulations of the four CYP450 detoxification genes in both six-day-old larvae and newly emerged workers. In conclusion, this study highlights the negative impact of cocoons in multi-generation brood cells on bee health and provides evidence supporting the development of rational apiculture management strategies for ecosystem stability.

Analysis of comb-gnawing behavior in Apis cerana cerana (Hymenoptera: Apidae).

Apis cerana cerana exhibits a prominent biological trait known as comb gnawing. In this study, gnawed combs from colonies during different seasons were collected, investigating the comb age and locations of gnawing. Patterns of comb gnawing were recorded, and the effects of 2 factors, namely, comb type and season, on the mass of wax residues and the gnawed surface area were measured. The results revealed that A. c. cerana predominantly gnaws combs that have been used for over 6 months, with gnawing concentrated in the brood-rearing area. In the first 3 seasons, significantly higher masses of wax residues and larger gnawed surface areas were found in greater wax moth larvae (GWML)-infested combs compared to newly built and old combs. Also, there were significantly higher masses and areas gnawed by A. c. cerana in old combs compared to newly built combs in all 4 seasons. Compared to other seasons, it exhibited significantly higher masses and areas resulting from comb-gnawing in newly built or old combs in winter. However, there were no significant differences in the masses of wax residues and surface areas gnawed in GWML-infested combs across the first 3 seasons. In conclusion, this study documented the impact of comb type and season on the comb-gnawing behavior of A. c. cerana, contributing to beekeeping management practices and the current understanding of bee biology.

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.

Comb Cell Structure and Morphological Characteristics of the Chinese Honey Bee, Apis cerana cerana (Hymenoptera: Apidae), Under Successive Generations.

This study investigated the changes in comb cell structure and external morphological characteristics of the Chinese honey bee under ten successive generations to determine the optimal time to replace the old combs. Accordingly, ten Chinese honey bee experimental colonies were established, and natural combs were constructed for continuous rearing of workers for 1-10 generations. The brood comb thickness, brood cell structure, birth weight, and morphological characteristics of workers were determined. Pearson correlation analyses between brood comb structure and morphological characteristics of workers were carried out. The results revealed that under ten successive generations, the color of the brood comb deepens from white or light yellow to brown and finally to black. Also, concerning the brood cell shape, the cell base changes from the three-rhomboid structure to the hemisphere, and the cell body changes from the hexagonal prism structure to the cylinder. The brood cell depth increases with an increase in brood comb thickness. The cell volume reduces with the hexagonal cell's decreasing inner circumference side length, and diameter. A smaller cell volume leads to a decrease in the birth weight and body size of the worker, in addition, the Chinese honey bee has gnawed off the comb cells that have been cultivated for eight generations. This study suggests that the combs of Chinese honey bees should be replaced after eight generations to improve colony strength and production performance.

Prediction of Refracturing Effect of Tight Gas Reservoirs Based on Bayesian Inversion Algorithm.

As a key technology for tight gas stimulation, refracturing plays an important role in tight gas development. In the production process of tight gas wells, the reservoir or fracturing process may cause the hydraulic fractures to gradually fail and the production to continuously decrease. In order to restore the productivity of a single well, it is necessary to refract the well to reopen the failed fractures or fracturing. Reasonable refracturing timing and optimization of refract fracture parameters are important guarantees to ensure the benefits of refracturing in tight gas wells, and relevant research on it can provide theoretical and technical guidance for field construction design. Based on the inverse problem of the dynamic prediction model of tight gas well productivity, this paper proposes an inversion method of formation and fracture parameters before refracturing based on Bayesian inversion algorithm. Finally, based on the geology and development data of the fractured wells in the Sulige gas field, the field application of refracting well selection, determination of refracting reasonable timing, and prediction of refracting effect is carried out. The actual production data are compared, and it is shown that this method can provide theoretical guidance for high-efficiency production-increasing construction on-site.

Characterization and Developmental Expression Patterns of Four Hexamerin Genes in the Bumble Bee, Bombus terrestris (Hymenoptera: Apidae).

Hexamerins are members of the hemocyanin superfamily and play essential roles in providing amino acids and energy for the nonfeeding stages of insects. In this study, we cloned and analyzed the expression patterns of four hexamerin genes (hex 70a, hex 70b, hex 70c, and hex 110) at different worker development stages and queen diapause statuses in the bumble bee, Bombus terrestris. The results of this study showed that hex 110 has the longest open reading frame (ORF; 3,297 bp) compared to the ORFs of hex 70a (2,034 bp), hex 70b (2,067 bp), and hex 70c (2,055 bp). The putative translation product of Hex 70a, Hex 70b, Hex70c, and Hex 110 has 677, 688, 684, and 1,098aa with predicted molecular mass of 81.13, 79.69, 81.58, and 119 kDa. In the development stages of workers, the expression levels of hex 70a, hex 70b, and hex 70c increased gradually from the larval stage and exhibited high expression levels at the pink eyed and brown eyed pupae stage, whereas hex 110 exhibited the highest expression level at the larval period. Four hexamerin genes were highly expressed at the prediapause status of queen (P < 0.05), and compared to the eclosion queen, the lowest upregulation was 3.7-fold, and the highest upregulation was 1,742-fold. The expression levels of hex 70b, hex 70c, and hex 110 at diapause were significantly higher than those at postdiapause (P < 0.05). In conclusion, hexamerins may play important roles in queen diapause and metamorphosis of larval and pupal stages.

IRP30 promotes worker egg-laying in bumblebee, Bombus terrestris (Hymenoptera: Apidae).

Bumblebees are important pollinators that have evolved between solitary and advanced eusocial insects. Compared with advanced honeybees, workers of social bumblebee species are prone to laying eggs during the competition phase, which leads to the end of the colony. Therefore, worker reproductive behavior has become a popular research topic for exploring various biological phenomena. Here, we demonstrate a novel reproduction-related function of an immune response protein-encoding gene (Immune Responsive Protein 30, IRP30) in Bombus terrestris by employing RNA interference (RNAi) and a transgenic Drosophila melanogaster system. The results show that worker egg-laying was significantly affected by IRP30 expression levels (P < 0.01). Compared with those in the dsGFP-treated groups, the first egg-laying time was delayed by 3.7 d and the egg number was decreased by 41% in the dsIRP30-treated group. In addition, the average size of the largest oocyte and the relative mRNA expression levels of Vg (vitellogenin) were significantly reduced in the dsIRP30-treated group (P < 0.05). Cellular localization by immunofluorescence demonstrated that IRP30 has important functions in the germ cells of workers' ovarioles. Overexpression of IRP30 was confirmed to increase the reproductive capability of the transgenic D. melanogaster. In conclusion, IRP30 regulates worker egg-laying by affecting the expression of Vg, the size of the ovary and the formation of the oocyte. These findings provide essential information for understanding the mechanisms underlying worker reproductive regulation.