Isorhamnetin Downregulates MMP2 and MMP9 to Inhibit Development of Rheumatoid Arthritis through SRC/ERK/CREB Pathway.

OBJECTIVE: To investigate the effect of isorhamnetin on the pathology of rheumatoid arthritis (RA). METHODS: Tumor necrosis factor (TNF)- α -induced fibroblast-like synoviocytes (FLS) was exposed to additional isorhamnetin (10, 20 and 40 µ mol/L). Overexpression vectors for matrix metalloproteinase-2 (MMP2) or MMP9 or SRC were transfected to explore their roles in isorhamnetin-mediated RA-FLS function. RA-FLS viability, migration, and invasion were evaluated. Moreover, a collagen-induced arthritis (CIA) rat model was established. Rats were randomly divided to sham, CIA, low-, medium-, and high-dosage groups using a random number table (n=5 in each group) and administed with normal saline or additional isorhamnetin [2, 10, and 20 mg/(kg·day)] for 4 weeks, respectively. Arthritis index was calculated and synovial tissue inflammation was determined in CIA rats. The levels of MMP2, MMP9, TNF-α, interleukin-6 (IL-6), and IL-1 ß, as well as the phosphorylation levels of SRC, extracellular regulated kinase (ERK), and cyclic adenosine monophosphate response element-binding (CREB), were detected in RA-FLS and synovial tissue. Molecular docking was also used to analyze the binding of isorhamnetin to SRC. RESULTS: In in vitro studies, isorhamnetin inhibited RA-FLS viability, migration and invasion (P<0.05). Isorhamnetin downregulated the levels of MMP2, MMP9, TNF-α, IL-6, and IL-1 ß in RA-FLS (P<0.05). The overexpression of either MMP2 or MMP9 reversed isorhamnetin-inhibited RA-FLS migration and invasion, as well as the levels of TNF-α, IL-6, and IL-1 ß (P<0.05). Furthermore, isorhamnetin bound to SRC and reduced the phosphorylation of SRC, ERK, and CREB (P<0.05). SRC overexpression reversed the inhibitory effect of isorhamnetin on RA-FLS viability, migration and invasion, as well as the negative regulation of MMP2 and MMP9 (P<0.05). In in vivo studies, isorhamnetin decreased arthritis index scores (P<0.05) and alleviated synovial inflammation. Isorhamnetin reduced the levels of MMP2, MMP9, TNF-α, IL-6, and IL-1 ß, as well as the phosphorylation of SRC, ERK, and CREB in synovial tissue (P<0.05). Notably, the inhibitory effect of isorhamnetin was more pronounced at higher concentrations (P<0.05). CONCLUSION: Isorhamnetin exhibited anti-RA effects through modulating SRC/ERK/CREB and MMP2/MMP9 signaling pathways, suggesting that isorhamnetin may be a potential therapeutic agent for RA.

[Research progress on Rhododendron molle in treatment of rheumatoid arthritis].

Rheumatoid arthritis(RA), as a chronic autoimmune disease, has a high incidence and disability rate, causing significant suffering to patients. Due to its complex pathogenesis, it has not been fully elucidated to date, and its treatment remains a challenging problem in the medical field. Although western medicine treatment options have certain efficacy, they require prolonged use and are expensive. Additionally, they carry risks of multiple infections and adverse reactions like malignancies. The Chinese herbal medicine Rhododendron molle is commonly used in folk medicine for its properties of dispelling wind, removing dampness, calming nerves, and alleviating pain in the treatment of diseases like rheumatic bone diseases. In recent years, modern clinical and pharmacological studies have shown that the diterpenoids in R. molle are effective components, exhibiting immune-regulatory, anti-inflammatory, and analgesic effects. This makes it a promising candidate for treating RA with a broad range of potential applications. However, R. molle has certain toxic properties that hinder its clinical application and lead to the wastage of its resources. This study reviewed recent research progress on the mechanism of R. molle in preventing and treating RA, focusing on its chemical components, anti-inflammatory and analgesic properties and summarized the adverse reactions associated with R. molle, aiming to offer new ideas for finding natural remedies for RA and methods to reduce toxicity while enhancing the effectiveness of R. molle. The study seeks to clarify the safety and efficacy of R. molle and its extracts, providing a theoretical basis for its application prospects and further promoting the development and utilization of R. molle resources.

Comparative transcriptome analysis to reveal key ethylene genes involved in a Lonicera macranthoides mutant.

BACKGROUND: Lonicera macranthoides Hand.-Mazz. is an important medicinal plant. Xianglei-type (XL) L. macranthoides was formed after many years of cultivation by researchers on the basis of the natural mutant. The corolla of L. macranthoides XL remains unexpanded and its flowering period is nearly three times longer than that of wild-type (WT) plants. However, the molecular mechanism behind this desirable trait remains a mystery. OBJECTIVE: To understand the floral phenotype differences between L. macranthoides and L. macranthoides XL at the molecular level. METHODS: Transcriptome analysis was performed on L. macranthoides XL and WT. One DEG was cloned by RT-PCR amplification and selected for qRT-PCR analysis. RESULTS: Transcriptome analysis showed that there were 5603 differentially expressed genes (DEGs) in XL vs. WT. Enrichment analysis of DEGs showed that pathways related to plant hormone signal transduction were significantly enriched. We identified 23 key genes in ethylene biosynthesis and signal transduction pathways. The most abundant were the ethylene biosynthesis DEGs. In addition, the open reading frames (ORFs) of WT and XL ETR2 were successfully cloned and named LM-ETR2 (GenBank: MW334978) and LM-XL-ETR2 (GenBank: MW334978), respectively. qRT-PCR at different flowering stages suggesting that ETR2 acts in the whole stage of flower development of WT and XL. CONCLUSIONS: This study provides new insight into the molecular mechanism that regulates the development of special traits in the flowers of L. macranthoides XL. The plant hormone ethylene plays an important role in flower development and flowering duration prolongation in L. macranthoides. The ethylene synthesis gene could be more responsible for the flower phenotype of XL. The genes identified here can be used for breeding and improvement of other flowering plants after functional verification.

A Study on the Pharmacological Effects and Mechanism of Rhodojaponin III in Rheumatoid Arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory disease with a high rate of disability accompanied by various complications. The pathogenesis of RA is complex with multiple targets and links. This study aims to investigate pharmacological effects and mechanism of Rhodojaponin III in RA. METHODS: The bovine type II collagen-induced arthritis (CIA) rat model and tumor necrosis factor-alpha (TNF-α) induced human umbilical vein endothelial cells (HUVECs) model were constructed. Different concentrations of Rhodojaponin III were utilized for intervention. The progression of CIA was assessed by the arthritis index (AI). Pathological changes in knee joints and synovium were observed. The expressions of angiogenesis-related cytokines were detected. The proliferation, migration, invasion, and angiogenesis of HUVECs were detected. The levels of pro-inflammatory cytokines were determined. The expressions of nuclear factor kappa B-inducing kinase (NIK) pathway-related proteins were analyzed. The binding of Rhodojaponin III to NIK was simulated by molecular docking. RESULTS: Rhodojaponin III suppressed cartilage damage and bone erosion in the knee joints. Rhodojaponin III inhibited expressions of platelet endothelial cell adhesion molecule-1 (CD31) and vascular endothelial cell growth factor (VEGF) to decrease vascular density. Rhodojaponin III suppressed the proliferation, migration, invasion, and angiogenesis of HUVECs, and decreased the levels of interleukin (IL)-6, IL-1ß, and TNF-α. Molecular docking showed that Rhodojaponin III could spontaneously bind to NIK. Rhodojaponin III decreased the expression of NIK, p52, and C-X-C motif chemokine ligand 12 (CXCL12) and the phosphorylation level of IκB kinase-alpha (IKKα) in the synovium of CIA rats and TNF-α-induced HUVECs. NIK overexpression reversed the inhibitory effect of Rhodojaponin III on activation of the NIK/NF-κB pathway, migration, invasion, and angiogenesis of HUVECs, and the secretion of pro-inflammatory cytokines. CONCLUSIONS: Rhodojaponin III affected the angiogenesis and inflammation of CIA rats and TNF-α-induced HUVECs by regulating the NIK/IKKα/CXCL12 pathway. These findings suggest that Rhodojaponin III has potential as a therapeutic agent for RA. Further studies are needed to explore its precise mechanism of action and evaluate its clinical efficacy.

[Studies on volatile oil from Atractylodes macrocephala with different distill methods].

OBJECTIVE: To study on volatice oil from Atractylodes macrosephala Koidz with different distill methods and find the better method. METHODS: GC-MS was used to analyze the chemical constituents of volatice oil from Atractylodes macrocephala Koidz with different distill methods. RESULTS: The extraction rates of volatice oil with steam distillation was 1.01%, the components of the oil were examined by GC-MS, 15 of the 18 were identified. The extraction rates of volatice oil with ultrasonic wave was 1.60%, the components examined, 20 of the 24 were identified. The extraction rates of volatice oil with SFE-CO2 was 2.32%, the components examined, 37 of the 49 were identified. Atractylon was the highest one. There were 12 common components in the identified ones. CONCLUSION: The components of volatice oil from Atractylodes macrocephala Koidz with different distill methods have difference but similarities, it can provide a method for Atractylodes macrocephala Koidz's quality control. The extraction rates is higher and the components are more with the method of SFE-CO2.