Si Miao San Attenuates Inflammation and Oxidative Stress in Rats with CIA via the Modulation of the Nrf2/ARE/PTEN Pathway

Analgesic and anti-inflammatory effects of galangin: a potential pathway to inhibit transient receptor potential vanilloid 1 receptor activation

Background

Galangin, commonly employed in traditional Chinese medicine for its diverse medicinal properties, exhibits potential in treating inflammatory pain. Nevertheless, its mechanism of action remains unclear.

Methods

Mice were randomly divided into 4 groups for 7 days: a normal control group, a galangin-treated (25 and 50 mg/kg), and a positive control celecoxib (20 mg/kg). Analgesic and anti-inflammatory effects were evaluated using a hot plate test, acetic acid-induced writhing test, acetic acid-induced vascular permeability test, formalininduced paw licking test, and carrageenan-induced paw swelling test. The interplay between galangin, transient receptor potential vanilloid 1 (TRPV1), NF-κB, COX-2, and TNF-α proteins was evaluated via molecular docking. COX- 2, PGE2, IL-1β, IL-6, and TNF-α levels in serum were measured using ELISA after capsaicin administration (200 nmol/L). TRPV1 expression in the dorsal root ganglion was analyzed by Western blot. The quantities of substance P (SP) and calcitonin gene-related peptide (CGRP) were assessed using qPCR.

Results

Galangin reduced hot plate-induced licking latency, acetic acid-induced contortions, carrageenantriggered foot inflammation, and capillary permeability in mice. It exhibited favorable affinity towards TRPV1, NF- κB, COX-2, and TNF-α, resulting in decreased levels of COX-2, PGE2, IL-1β, IL-6, and TNF-α in serum following capsaicin stimulation. Galangin effectively suppressed the upregulation of TRPV1 protein and associated receptor neuropeptides CGRP and SP mRNA, while concurrently inhibiting the expression of NF-κB, TNF-α, COX-2, and PGE2 mRNA.

Conclusions

Galangin exerts its anti-inflammatory pain effects by inhibiting TRPV1 activation and regulating COX-2, NF-κB/TNF-α expression, providing evidence for the use of galangin in the management of inflammatory pain.

Si Miao San relieves hyperuricemia by regulating intestinal flora

This study seeks to investigate the therapeutic effects of Si Miao San (SMS) on hyperuricemia and its underlying mechanisms, particularly focusing on the role of intestinal flora. The key components of SMS were identified using high-performance liquid chromatography (HPLC). To establish a rat model of hyperuricemia, an intraperitoneal injection of potassium oxonate was performed, followed by oral administration of various concentrations of SMS. The study evaluated the status of hyperuricemia, renal pathology, xanthine oxidase (XO) activity, and intestinal flora. Utilizing HPLC, we identified five active components of SMS. Following SMS intervention, there was a significant reduction in serum levels of uric acid (UA), blood urea nitrogen, and creatinine, accompanied by an increase in urine UA levels in rats with hyperuricemia. Distinct pathological injuries were evident in the renal tissues of hyperuricemic rats, and these were partially alleviated following SMS intervention. Moreover, SMS exhibited a dose-dependent reduction in XO activity both in the serum and hepatic tissues. Notably, SMS contributed to an enhancement in the diversity of intestinal flora in hyperuricemic rats. The intervention of SMS resulted in a reduction in the abundance of certain bacterial species, including Parabacteroides johnsonii, Corynebacterium urealyticum, and Burkholderiales bacterium. This suggests that SMS may exert anti-hyperuricemia effects, potentially by modulating the composition of intestinal flora.

NFIC attenuates rheumatoid arthritis-induced inflammatory response in mice by regulating PTEN/SENP8 transcription

OBJECTIVE

To explore whether nuclear factor I C (NFIC) alleviated inflammatory response of synovial fibroblasts (SFs) caused by rheumatoid arthritis (RA) by regulating transcription levels of phosphatase and tension homolog deleted on chromosome 10 (PTEN) and sentrin-specific protease 8 (SENP8).

METHODS

NFIC, PTEN, and SENP8 levels in RASFs and normal SFs (NSFs) were measured by qRT-PCR and western blotting. The levels of Bax, Bcl-2, MMP-3, and MMP-13, as well as the content of superoxide dismutase (SOD) and malondialdehyde (MDA) were determined in RASFs and NSFs using western blotting and ELISA. The binding of NFIC to promoter sequences of PTEN and SENP8 was predicted and verified. A mouse model of collagen-induced arthritis (CIA) was established and evaluated according to the degree of joint swelling and arthritis index.

RESULTS

NFIC, PTEN, and SENP8 were downregulated in RASFs. RASFs had increased viability and MDA levels as well as decreased cell apoptosis and SOD content. NFIC was demonstrated to modulate the transcription of PTEN and SENP8 as their transcription factor. NFIC ameliorated the inflammatory response induced by RA in vivo by promoting the transcription of PTEN and SENP8.

CONCLUSION

NFIC acted as a transcription factor to facilitate the transcription of PTEN and SENP8, thereby inducing apoptosis of RASFs and effectively attenuating inflammatory response in CIA mice.

Antioxidant glutathione inhibits inflammation in synovial fibroblasts via PTEN/PI3K/AKT pathway: An in vitro study

Objectives

In this study, we aimed to investigate whether glutathione (GSH) could decrease the secretion of reactive oxygen species (ROS), reduce inflammation, and modulate the phosphatase and tensin homolog deleted on chromosome 10/phosphatidylinositol 3-kinase/AKT (PTEN/PI3K/AKT) in synovial fibroblasts (SFs).

Patients and methods

A total of 30 DBA/1J female mice were used in this study. The release of ROS in MH7A cells was examined using a ROS assay kit. The effects of GSH on the messenger ribonucleic acid (mRNA) expression and protein levels of inflammatory cytokines were determined via reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA) in mouse SFs and MH7A cells, respectively. The PTEN/PI3K/AKT pathway was investigated via Western blotting. The effects of buthionine-sulfoximine (BSO), as an inhibitor of GSH, on these molecules were examined.

Results

The ROS were decreased after GSH treatment, and the mRNA levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-6, matrix metalloproteinase (MMP)-1, MMP-3, were also significantly inhibited after GSH stimulation. However, the IL-10 levels were enhanced, and GSH increased the expression of PTEN. The GSH suppressed the activation of phosphorylated (p)-PI3K and p-AKT. The supplementation of the BSO restored the activation of PI3K/AKT pathway with a high production of ROS. The levels of TNF-α, IL-1β and IL-6 were also elevated, when the BSO was added.

Conclusion

These findings suggest that GSH can act as an inflammatory suppressor by downregulating the PTEN/PI3K/AKT pathway in MH7A cells. These data indicated a novel function of GSH for improving the inflammation of RA SFs and may help to alleviate the pathological process of RA.

Deferoxamine Reduces Inflammation and Osteoclastogenesis in Avulsed Teeth

Replacement and inflammatory resorption are serious complications associated with the delayed replantation of avulsed teeth. In this study, we aimed to assess whether deferoxamine (DFO) can suppress inflammation and osteoclastogenesis in vitro and attenuate inflammation and bone resorption in a replanted rat tooth model. Cell viability and inflammation were evaluated in RAW264.7 cells. Osteoclastogenesis was confirmed by tartrate-resistant acid phosphatase staining, reactive oxygen species (ROS) measurement, and quantitative reverse transcriptase–polymerase chain reaction in teeth exposed to different concentrations of DFO. In vivo, molars of 31 six-week-old male Sprague–Dawley rats were extracted and stored in saline (n = 10) or DFO solution (n = 21) before replantation. Micro-computed tomography (micro-CT) imaging and histological analysis were performed to evaluate inflammation and root and alveolar bone resorption. DFO downregulated the genes related to inflammation and osteoclastogenesis. DFO also reduced ROS production and regulated specific pathways. Furthermore, the results of the micro-CT and histological analyses provided evidence of the decrease in inflammation and hard tissue resorption in the DFO group. Overall, these results suggest that DFO reduces inflammation and osteoclastogenesis in a tooth replantation model, and thus, it has to be further investigated as a root surface treatment option for an avulsed tooth.

[The low expression of long non-coding RNA Linc00638 contributes to rheumatoid arthritis progression by regulating inflammation and oxidative stress]

OBJECTIVE

To investigate the expression of long non-coding RNA (lncRNA) Linc00638 in rheumatoid arthritis (RA) and its regulatory role in inflammation and oxidative stress of synovial fibroblasts in RA patients (RA-FLS).

METHODS

Peripheral blood mononuclear cells (PBMCs) were collected from 20 healthy individuals and 35 RA patients for detecting the expression of Linc00638 using RT-qPCR to analyze the correlation of Linc00638 expression with the clinical indicators of RA patients. A Linc00638 overexpression plasmid and siRNA targeting Linc00638 were transfected into RA-FLS, and the changes in cell viability was observed using CCK8 assay; the changes in the expression levels of interleukin-4 (IL-4), IL-6, reactive oxygen species (ROS) and superoxide dismutase (SOD) in the supernatant were detected using ELISA.

RESULTS

Compared with the healthy control subjects, RA patients had significantly increased ESR, CRP, RF, anti-CCP, IgA, and C4 levels (P < 0.05) and significantly decreased Linc00638 expression in the PBMCs (P < 0.01). The area under the receiver-operating characteristic (ROC) curve of Linc00638 was 91.86% with the best cut-off value of 0.74 for diagnosis of RA. Spearman correlation analysis showed that Linc00638 expression level was negatively correlated with age, course of disease, DAS28, ESR, CRP, RF and anti-CCP, and positively correlated with IL-4 and SOD levels (P < 0.05). Association rule analysis showed that a decreased Linc00638 expression was strongly correlated with an increase of age (>60 years), a longer disease course (>10 years), elevated levels of ESR, RF and anti-CCP, and decreased levels of IL-4 and SOD. In RA-FLS, overexpression of Linc00638 significantly inhibited while Linc00638 interference obviously enhanced the cell viability. Over-expression of Linc00638 also significantly increased the levels of IL-4 and SOD (P < 0.05) and decreased the expressions of IL-6 and ROS (P < 0.05), while interference of Linc00638 produced the opposite effects in the cells (P < 0.05).

CONCLUSION

RA patients have low expression levels of Linc00638, which may participate in disease progression by regulating inflammation and oxidative stress.