Effects of schisandrin on transcriptional factors in lipopolysaccharide-pretreated macrophages

A comprehensive review on Schisandrin and its pharmacological features

Schisandrin stands as one of the primary active compounds within the widely used traditional medicinal plant Schisandra chinensis (Turcz.) Baill. This compound exhibits sedative, hypnotic, anti-aging, antioxidant, and immunomodulatory properties, showcasing its effectiveness across various liver diseases while maintaining a favorable safety profile. However, the bioavailability of schisandrin is largely affected by hepatic and intestinal first-pass metabolism, which limits the clinical efficacy of schisandrin. In this paper, we review the various pharmacological effects and related mechanisms of schisandrin, in order to provide reference for subsequent drug research and promote its medicinal value.

Schisandrin protects against ulcerative colitis by inhibiting the SGK1/NLRP3 signaling pathway and reshaping gut microbiota in mice

BACKGROUND

According to the Chinese Pharmacopoeia, the fruit of Schisandra chinensis (Turcz.) Baill. (SC) is an important traditional Chinese medicine that can be used to treat diarrhea. Despite the increasing research on the anti-inflammatory and anti-oxidant aspects of SC, the studies on the anti-ulcerative colitis of Schisandrin (SCH), the main constituent of SC, are relatively few.

METHODS

The mice used in the study were randomly distributed into 6 groups: control, model, 5-ASA, and SCH (20, 40, 80 mg/kg/d). The mice in the model group were administered 3% (w/v) dextran sulfate sodium (DSS) through drinking water for 7 days, and the various parameters of disease activity index (DAI) such as body weight loss, stool consistency, and gross blood were measured. ELISA was used to detect inflammatory factors, and bioinformatics combined with transcriptome analysis was done to screen and verify relevant targets. 16S rDNA high-throughput sequencing was used to analyze the composition of the gut microbiota(GM), while mass spectrometry was done to analyze the changes in the content of bile acids (BAs) in the intestine.

RESULTS

Mice treated with SCH experienced significant weight gain, effectively alleviating the severity of colitis, and decreasing the levels of inflammatory factors such as TNF-α, IL-1β, IL-18, IL-6, and other related proteins (NLRP3, Caspase-1, SGK1) in UC mice. Furthermore, the analysis of GM and BAs in mice revealed that SCH increased the relative abundance of Lactobacilli spp, reduced the relative abundance of Bacteroides, and promoted the conversion of primary BAs to secondary BAs. These effects contributed to a significant improvement in the DSS-induced GM imbalance and the maintenance of intestinal homeostasis.

CONCLUSION

It seems that there is a close relationship between the SCH mechanism and the regulation of SGK1/NLRP3 pathway and the restoration of GM balance. Therefore, it can be concluded that SCH could be a potential drug for the treatment of UC.

Anti-arthritic effects of Schisandra chinensis extract in monosodium iodoacetate-induced osteoarthritis rats

The present study aimed to investigate the therapeutic effects of Schisandra chinensis (SC) extract on clinical symptoms of osteoarthritis and the modulating effect on the mechanisms associated with the progression of osteoarthritis in a rat model of monosodium iodoacetate (MIA)-induced osteoarthritis. Osteoarthritis-induced rats were randomized into four groups: MIA injection control (MC), MIA injection with celecoxib (PC), MIA injection with SC extract 100 mg/kg (SC100), and MIA injection with SC extract 200 mg/kg (SC200). Another healthy group received a saline injection as a negative control (NC). During the treatment, weight-bearing measurements were performed once a week for 4 weeks. Histopathological and biochemical analyses of the joints, blood, and chondrocyte tissue were performed following the completion of treatment. Compared with MC rats, SC rats demonstrated significantly alleviated pain behavior, bone erosion, and cartilage degradation. SC reduced serum levels of matrix metalloproteinases and pro-inflammatory cytokines. SC treatment also reversed the levels of biomarkers such as Collagen II and ADAMTS4 in the cartilage tissue. Moreover, SC administration inhibited the phosphorylation levels of nuclear factor kappa B (NF-κB) and NF-κB Inhibitor alpha. This study demonstrates that SC ameliorated osteoarthritis at in vivo level. Our results suggest that SC might be a potential therapeutic agent for osteoarthritis.

Impact of dibenzocyclooctadiene lignans from Schisandra chinensis on the redox status and activation of human innate immune system cells

Redox signaling has been established as an essential component of inflammatory responses, and redox active compounds are of interest as potential immunomodulatory agents. Dibenzocyclooctadiene lignans isolated from Schisandra chinensis, a medicinal plant with widespread use in oriental medicine, have been implicated to possess immunomodulatory properties but their effects on the human innate immune system cells have not been described. In this contribution, data are presented on the impact of schisandrin, schisandrin B and schisandrin C on human monocytic cell redox status, as well as their impact on dendritic cell maturation and T cell activation capacity and cytokine production. In THP-1 cells, levels of intracellular reactive oxygen species (ROS) were elevated after 1 h exposure to schisandrin. Schisandrin B and schisandrin C decreased cellular glutathione pools, which is a phenotype previously reported to promote anti-inflammatory functions. Treatment of human primary monocytes with the lignans during their maturation to dendritic cells did not have any effect on the appearance of surface markers HLA-DR and CD86 but schisandrin B and schisandrin C suppressed the secretion of cytokines interleukin (IL)-6, IL-10 and IL-12 by the mature dendritic cells. Dendritic cells maturated in presence of schisandrin C were further cocultured with naïve CD4+ T cells, resulting in reduced IL-12 production. In THP-1 cells, schisandrin B and schisandrin C reduced the IL-6 and IL-12 production triggered by E. coli lipopolysaccharide and IL-12 production induced by an infection with Chlamydia pneumoniae. In conclusion, the studied lignans act as immunomodulatory agents by altering the cytokine secretion, but do not interfere with dendritic cell maturation. And the observed effects may be associated with the ability of the lignans to alter cellular redox status.

Natural products for chronic cough: Text mining the East Asian historical literature for future therapeutics

Chronic cough is a significant health burden. Patients experience variable benefits from over the counter and prescribed products, but there is an unmet need to provide more effective treatments. Natural products have been used to treat cough and some plant compounds such as pseudoephedrine from ephedra and codeine from opium poppy have been developed into drugs. Text mining historical literature may offer new insight for future therapeutic development. We identified natural products used in the East Asian historical literature to treat chronic cough. Evaluation of the historical literature revealed 331 natural products used to treat chronic cough. Products included plants, minerals and animal substances. These natural products were found in 75 different books published between AD 363 and 1911. Of the 331 products, the 10 most frequently and continually used products were examined, taking into consideration findings from contemporary experimental studies. The natural products identified are promising and offer new directions in therapeutic development for treating chronic cough.

Gomisin A inhibits lipopolysaccharide-induced inflammatory responses in N9 microglia via blocking the NF-κB/MAPKs pathway

Gomisin A, one of the major dibenzocyclooctadiene lignans isolated from Schisandra chinensis Baill., has proved to possess a variety of pharmacological effects. The aim of the present study was to investigate the anti-inflammatory and neuroprotective effects of gomisin A as well as its potential molecular mechanisms. It was found that gomisin A not only inhibited the production of NO and PGE2 in a concentration-dependent manner but also suppressed the expressions of iNOS and COX-2 in LPS-stimulated N9 microglia without observable cytotoxicity. Gomisin A was also able to attenuate the mRNA expression and the production of pro-inflammatory factors TNF-α, IL-1β and IL-6. Moreover, LPS induced reactive oxygen species (ROS) production, NADPH oxidase activation, and gp91phox expression, which were markedly inhibited by gomisin A in microglia. Furthermore, the data showed that gomisin A significantly down-regulated the TLR4 protein expression, and inhibited nuclear transcription factor (NF)-κB and mitogen-activated protein kinases (MAPKs) signaling pathways. Additionally, gomisin A alleviated the cell death of SH-SY5Y neuroblastoma, rat primary cortical and hippocampal neurons induced by the conditioned-media from activated microglia. In summary, gomisin A may exert neuroprotective effects by attenuating the microglia-mediated neuroinflammatory response via inhibiting the TLR4-mediated NF-κB and MAPKs signaling pathways.