Differential Action between Schisandrin A and Schisandrin B in Eliciting an Anti-Inflammatory Action: The Depletion of Reduced Glutathione and the Induction of an Antioxidant Response

Evidence of synergistic mechanisms of hepatoprotective botanical herbal preparation of Pueraria montana var. lobata and Schisandra sphenanthera

Background

Pueraria montana var. lobata (Willd.) Maesen & S.M.Almeida ex Sanjappa & Predeep (syn. Pueraria lobata (Willd.) Ohwi) and Schisandra sphenanthera Rehder & E.H. Wilson are traditional edible and medicinal hepatoprotective botanical drugs. Studies have shown that the combination of two botanical drugs enhanced the effects of treating acute liver injury (ALI), but the synergistic effect and its action mechanisms remain unclear. This study aimed to investigate the synergistic effect and its mechanism of the combination of Pueraria montana var. lobata (Willd.) Maesen & S.M.Almeida ex Sanjappa & Predeep (syn. Pueraria lobata (Willd.) Ohwi) (PM) and Schisandra sphenanthera Rehder & E.H. Wilson (SS) in the treatment of ALI.

Methods

High performance liquid chromatography (HPLC) were utilized to conduct the chemical interaction analysis. Then the synergistic effects of botanical hybrid preparation of PM-SS (BHP PM-SS) against ALI were comprehensively evaluated by the CCl4 induced ALI mice model. Afterwards, symptom-oriented network pharmacology, transcriptomics and metabolomics were applied to reveal the underlying mechanism of action. Finally, the key target genes were experimentally by RT-qPCR.

Results

Chemical analysis and pharmacodynamic experiments revealed that BHP PM-SS was superior to the single botanical drug, especially at 2:3 ratio, with a better dissolution rate of active ingredients and synergistic anti-ALI effect. Integrated symptom-oriented network pharmacology combined with transcriptomics and metabolomics analyses showed that the active ingredients of BHP PM-SS could regulate Glutathione metabolism, Pyrimidine metabolism, Arginine biosynthesis and Amino acid sugar and nucleotide sugar metabolism, by acting on the targets of AKT1, TNF, EGFR, JUN, HSP90AA1 and STAT3, which could be responsible for the PI3K-AKT signaling pathway, MAPK signaling pathway and Pathway in cancer to against ALI.

Conclusion

Our study has provided compelling evidence for the synergistic effect and its mechanism of the combination of BHP PM-SS, and has contributed to the development and utilization of BHP PM-SS dietary supplements.

Research progress on the role of macrophages in acne and regulation by natural plant products

Acne vulgaris is one of the most common skin diseases. The current understanding of acne primarily revolves around inflammatory responses, sebum metabolism disorders, aberrant hormone and receptor expression, colonization by Cutibacterium acnes, and abnormal keratinization of follicular sebaceous glands. Although the precise mechanism of action remains incompletely understood, it is plausible that macrophages exert an influence on these pathological features. Macrophages, as a constituent of the human innate immune system, typically manifest distinct phenotypes across various diseases. It has been observed that the polarization of macrophages toward the M1 phenotype plays a pivotal role in the pathogenesis of acne. In recent years, extensive research on acne has revealed an increasing number of natural remedies exhibiting therapeutic efficacy through the modulation of macrophage polarization. This review investigates the role of cutaneous macrophages, elucidates their potential significance in the pathogenesis of acne, a prevalent chronic inflammatory skin disorder, and explores the therapeutic mechanisms of natural plant products targeting macrophages. Despite these insights, the precise role of macrophages in the pathogenesis of acne remains poorly elucidated. Subsequent investigations in this domain will further illuminate the pathogenesis of acne and potentially offer guidance for identifying novel therapeutic targets for this condition.

Selenium, Stroke, and Infection: A Threefold Relationship; Where Do We Stand and Where Do We Go?

Stroke is currently the second most common cause of death worldwide and a major cause of serious long-term morbidity. Selenium is a trace element with pleotropic effects on human health. Selenium deficiency has been associated with a prothrombotic state and poor immune response, particularly during infection. Our aim was to synthesize current evidence on the tripartite interrelationship between selenium levels, stroke, and infection. Although evidence is contradictory, most studies support the association between lower serum selenium levels and stroke risk and outcomes. Conversely, limited evidence on the role of selenium supplementation in stroke indicates a potentially beneficial effect of selenium. Notably, the relationship between stroke risk and selenium levels is bimodal rather than linear, with higher levels of serum selenium linked to disturbances of glucose metabolism and high blood pressure, morbidities which are, in turn, substrates for stroke. Another such substrate is an infection, albeit forming a bidirectional relationship with both stroke and the consequences of impaired selenium metabolism. Perturbed selenium homeostasis leads to impaired immune fitness and antioxidant capacity, which both favor infection and inflammation; specific pathogens may also contend with the host for transcriptional control of the selenoproteome, adding a feed-forward loop to this described process. Broader consequences of infection such as endothelial dysfunction, hypercoagulation, and emergent cardiac dysfunction both provide stroke substrates and further feed-forward feedback to the consequences of deficient selenium metabolism. In this review, we provide a synthesis and interpretation of these outlined complex interrelationships that link selenium, stroke, and infection and attempt to decipher their potential impact on human health and disease. Selenium and the unique properties of its proteome could provide both biomarkers and treatment options in patients with stroke, infection, or both.

The Pathogenesis of HCC Driven by NASH and the Preventive and Therapeutic Effects of Natural Products

Nonalcoholic steatohepatitis (NASH) is a clinical syndrome with pathological changes that are similar to those of alcoholic hepatitis without a history of excessive alcohol consumption. It is a specific form of nonalcoholic fatty liver disease (NAFLD) that is characterized by hepatocyte inflammation based on hepatocellular steatosis. Further exacerbation of NASH can lead to cirrhosis, which may then progress to hepatocellular carcinoma (HCC). There is a lack of specific and effective treatments for NASH and NASH-driven HCC, and the mechanisms of the progression of NASH to HCC are unclear. Therefore, there is a need to understand the pathogenesis and progression of these diseases to identify new therapeutic approaches. Currently, an increasing number of studies are focusing on the utility of natural products in NASH, which is likely to be a promising prospect for NASH. This paper reviews the possible mechanisms of the pathogenesis and progression of NASH and NASH-derived HCC, as well as the potential therapeutic role of natural products in NASH and NASH-derived HCC.

Sishen Pill Maintained Colonic Mucosal Barrier Integrity to Treat Ulcerative Colitis via Rho/ROCK Signaling Pathway

Sishen Pill (SSP) is a classical prescription of traditional Chinese medicine and often used to treat gastrointestinal diseases, including ulcerative colitis (UC). However, its mechanism is still unclear. We aimed to determine the mechanism of SSP in the treatment of UC by investigating if it maintains the integrity of the intestinal mucosal barrier via the Rho A/Rho kinase (ROCK) signaling pathway. Administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) successfully induced chronic UC in rats, while the treatment effect of SSP was evaluated by body weight change, colonic length, colonic weight, colonic weight index, histological injury score, and pathological injury score after colitis rats were treated for 7 days. TNF-α and IL-1β levels were analyzed by ELISA, and the proteins of PI3K/Akt and RhoA/ROCK signaling pathway and junction proteins expression were measured by western blotting assay, and the distribution of Claudin 5 was shown by immunofluorescence. SSP significantly improved the clinical symptoms of colitis in rats and reduced the expression of p-RhoA, ROCK1, PI3K, and Akt in the colon mucosa, while it increased the expression of p-Rac and related proteins (Claudin-5, JAM1, VE-cadherin, and Connexin 43). In addition, SSP increased p-AMPKα and PTEN proteins expression, decreased Notch1 level, and hinted that activation of the PI3K/Akt signaling pathway was inhibited. In conclusion, SSP effectively treated chronic colitis induced by TNBS, which may have been achieved by inhibiting PI3K/Akt signal to suppress activation of the Rho/ROCK signaling pathway to finally maintain the integrity of the intestinal mucosal barrier.

Schisandrin B regulates macrophage polarization and alleviates liver fibrosis via activation of PPARγ

Background

Schisandrin B (Sch B), the main ingredient of Schisandra chinensis, displays many bioactivities. This study aimed to identify the drug target of Sch B against liver fibrosis and describe the related molecular mechanisms.

Methods

The effects of Sch B on liver fibrosis and macrophage polarization was investigated in vivo and in vitro. Furthermore, we analyzed the regulatory effect of Sch B on peroxisome proliferator-activated receptor gamma (PPARγ).

Results

Our data showed that Sch B dramatically alleviated liver inflammation and fibrosis and inhibited macrophage activation via PPARγ. Sch B binds with PPARγ by molecular docking. Immunofluorescence double staining showed that PPARγ was mainly expressed in macrophages rather than hepatic stellate cells (HSCs) in liver fibrosis. Importantly, Sch B strongly inhibited macrophage polarization in fibrotic livers compared with the model group. Further, the results revealed that Sch B efficiently inhibited macrophage polarization and also decreased the levels of inflammatory cytokines in vitro. Knockdown of PPARγ by small interfering RNA (siRNA) inhibited the effect of Sch B on macrophage polarization. Mechanistically, Sch B regulated macrophage polarization through inhibition of the nuclear factor (NF)-κB signaling pathway via PPARγ both in vivo and in vitro.

Conclusions

These results suggested that Sch B alleviated carbon tetrachloride (CCl₄)-induced liver inflammation and fibrosis by inhibiting macrophage polarization via targeting PPARγ.

An Integrative Pharmacology Based Analysis of Refined Liuweiwuling Against Liver Injury: A Novel Component Combination and Hepaprotective Mechanism

Liver disease is a major cause of illness and death worldwide. In China, liver diseases, primarily alcoholic and nonalcoholic fatty liver disease, and viral hepatitis, affect approximately 300 million people, resulting in a major impact on the global burden of liver diseases. The use of Liuweiwuling (LWWL), a traditional Chinese medicine formula, approved by the Chinese Food and Drug Administration for decreasing aminotransferase levels induced by different liver diseases. Our previous study indicated a part of the material basis and mechanisms of LWWL in the treatment of hepatic fibrosis. However, knowledge of the materials and molecular mechanisms of LWWL in the treatment of liver diseases remains limited. Using pharmacokinetic and network pharmacology methods, this study demonstrated that the active components of LWWL were involved in the treatment mechanism against liver diseases and exerted anti-apoptosis and anti-inflammatory effects. Furthermore, esculetin, luteolin, schisandrin A and schisandrin B may play an important role by exerting anti-inflammatory and hepatoprotective effects in vitro. Esculeti and luteolin dose-dependently inhibited H₂O₂-induced cell apoptosis, and luteolin also inhibited the NF-κB signaling pathway in bone marrow-derived macrophages. schisandrin A and B inhibited the release of ROS in acetaminophen (APAP)-induced acute liver injury in vitro. Moreover, LWWL active ingredients protect against APAP-induced acute liver injury in mice. The four active ingredients may inhibit oxidative stress or inflammation to exert hepatoprotective effect. In conclusion, our results showed that the novel component combination of LWWL can protect against APAP-induced acute liver injury by inhibiting cell apoptosis and exerting anti-inflammatory effects.

Pathogenesis of NASH and Promising Natural Products

Nonalcoholic steatohepatitis (NASH) is a common clinical condition that can lead to advanced liver diseases. The mechanism of the diaease progression, which is lacking effective therapy, remains obsure. Therefore, there is a need to understand the pathogenic mechanisms responsible for disease development and progression in order to develop innovative therapies. To accomplish this goal, experimental animal models that recapitulate the human disease are necessary. Currently, an increasing number of studies have focused on natural constituents from medicinal plants which have been emerged as a new hope for NASH. This review summarized the pathogenesis of NASH, animal models commonly used, and the promising targets for therapeutics. We also reviewed the natural constituents as potential NASH therapeutic agents.

Schisandrin B Inhibits Osteoclastogenesis and Protects Against Ovariectomy-Induced Bone Loss

Osteoporosis is a systemic skeletal disease which is highly prevalent worldwide and considered to be associated with excessive bone resorption mediated by osteoclast. Osteoclast differentiation is featured by the activation of inflammation-related pathways and the generation of reactive oxygen species. Schisandrin B is a bioactive compound with strong antiinflammation and antioxidative properties, we thus speculated that Schisandrin B might serve as a potential candidate for osteoporosis. In the present study, we found that the formation and` function of osteoclasts were dramatically suppressed by Schisandrin B. And consistent with the in vitro results, treatment with Schisandrin B attenuated ovariectomy-induced bone loss in mice. Moreover, Schisandrin B notably inhibited the activation of mitogen activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways and scavenged ROS by activating nuclear factor E2 p45-related factor 2 (Nrf2) signaling. In conclusion, our study indicates that Schisandrin B is an effective approach to treat osteoporosis and other osteoclast-related diseases.

Evidence of anti-inflammatory activity of Schizandrin A in animal models of acute inflammation

Schisandrin A (Sch A) is a lignin extracted from the fruit of Schisandra chinensis, which has potential anti-inflammatory properties and is used for treating various inflammatory diseases. In this study, we aimed to evaluate the anti-inflammatory effects of Sch A and the underlying mechanisms in animal models of acute inflammation. First, the anti-inflammatory effects of Sch A were evaluated preliminarily in an animal model of xylene-induced ear edema. Sch A pretreatment significantly decreased the degree of edema and inhibited telangiectasia in the ear. Second, a mouse model of paw edema was used to investigate the anti-inflammatory effects and mechanisms of Sch A. Pretreatment with Sch A significantly inhibited carrageenan-induced paw edema in mice. Hematoxylin-eosin (HE) staining of paw tissues demonstrated that Sch A inhibited the infiltration of inflammatory cells in the mouse model of paw edema. Enzyme-linked immunosorbent assay (ELISA) results indicated that the levels of inflammatory factors decreased. The western blot and immunohistochemical assay results revealed that the toll-like receptor 4/nuclear factor kappa-B (TLR4/NF-κB) pathway could play a role in the anti-inflammatory functions of Sch A. The findings demonstrated that Sch A exerts anti-inflammatory effects and may provide possible strategies for the treatment of inflammatory diseases.

Schisandrin A protects intestinal epithelial cells from deoxynivalenol-induced cytotoxicity, oxidative damage and inflammation

Extensive research has revealed the association of continued oxidative stress with chronic inflammation, which could subsequently affect many different chronic diseases. The mycotoxin deoxynivalenol (DON) frequently contaminates cereals crops worldwide, and are a public health concern since DON ingestion may result in persistent intestinal inflammation. There has also been considerable attention over the potential of DON to provoke oxidative stress. In this study, the cytoprotective effect of Schisandrin A (Sch A), one of the most abundant active dibenzocyclooctadiene lignans in the fruit of Schisandra chinensis (Turcz.) Baill (also known as Chinese magnolia-vine), was investigated in HT-29 cells against DON-induced cytotoxicity, oxidative stress and inflammation. Sch A appeared to protect against DON-induced cytotoxicity in HT-29 cells, and significantly lessened the DON-stimulated intracellular reactive oxygen species and nitrogen oxidative species production. Furthermore, Sch A lowered DON-induced catalase, superoxide dismutase and glutathione peroxidase antioxidant enzyme activities but maintains glutathione S transferase activity and glutathione levels. Mechanistic studies suggest that Sch A reduced DON-induced oxidative stress by down-regulating heme oxygenase-1 expression via nuclear factor (erythroid-derived 2)-like 2 signalling pathway. In addition, Sch A decreased the DON-induced cyclooxygenase-2 expression and prostaglandin E2 production and pro-inflammatory cytokine interleukin 8 expression and secretion. This may be mediated by preventing DON-induced translocation of nuclear factor-κB, as well as activation of mitogen-activated protein kinases pathways. In the light of these findings, we concluded that Sch A exerted a cytoprotective role in DON-induced toxicity in vitro, and it would be valuable to examine in vivo effects.

Potential of Schisandra chinensis (Turcz.) Baill. in Human Health and Nutrition: A Review of Current Knowledge and Therapeutic Perspectives

Schisandra chinensis (Turcz.) Baill. (SCE) is a plant with high potential for beneficial health effects, confirmed by molecular studies. Its constituents exert anti-cancer effects through the induction of cell cycle arrest and apoptosis, as well as inhibition of invasion and metastasis in cancer cell lines and experimental animals. SCE displays antimicrobial effects against several pathogenic strains. It has anti-diabetic potential, supported by hypoglycemic activity. A diet rich in SCE improves pancreatic functions, stimulates insulin secretion, and reduces complications in diabetic animals. SCE prevents lipid accumulation and differentiation of preadipocytes, indicating its anti-obesity potential. SCE exerts a protective effect against skin photoaging, osteoarthritis, sarcopenia, senescence, and mitochondrial dysfunction, and improves physical endurance and cognitive/behavioural functions, which can be linked with its general anti-aging potency. In food technology, SCE is applied as a preservative, and as an additive to increase the flavour, taste, and nutritional value of food. In summary, SCE displays a variety of beneficial health effects, with no side effects. Further research is needed to determine the molecular mechanisms of SCE action. First, the constituents responsible for its beneficial effects should be isolated and identified, and recommended as preventative nutritional additives, or considered as therapeutics.

Schisandrin A Inhibits the IL-1β-Induced Inflammation and Cartilage Degradation via Suppression of MAPK and NF-κB Signal Pathways in Rat Chondrocytes

Osteoarthritis (OA) is a common joint disease in the elderly population. Its development has been reported to be associated with cartilage degradation and inflammatory responses. Schisandrin A, a bioactive lignin in Schisandra sphenanthera, has shown its anti-inflammatory potential in various inflammation diseases. However, the effects of Schisandrin A on OA remain to explore. In this study, rat chondrocytes were treated with IL-1β (10 ng/ml) with or without different concentrations of Schisandrin A for 24 h. Cell viability was evaluated by CCK-8 assay. Production of nitric oxide (NO) and prostaglandin E2 (PGE2) was measured by the Griess reaction and ELISA. The MAPK/NF-κB-related signaling molecules expression and the protein production of inducible nitric oxide synthase (iNOS), cyclooxygenase (Cox)-2, MMPs (MMP1, MMP3, MMP13), ADAMTS5, Collagen II, aggrecan, and Sox9 were detected by Western blot. Protein expression of Collagen II, aggrecan, and p65 nuclear translocation was evaluated by immunofluorescence. In vivo, intra-articular injection of 50 μM Schisandrin A or equal volume of vehicle was performed on rat OA models. Severity of cartilage damage was evaluated by HE and Safranin-O-Fast green staining. Our results revealed that Schisandrin A could suppress the IL-1β-induced production of NO and PGE2 in rat chondrocytes. Consistent with these findings, the upregulation of iNOS and Cox2 could also been decreased by Schisandrin A. Additionally, Schisandrin A could inhibit IL-1β-induced cartilage matrix catabolic enzymes including MMPs and ADAMTS5. Moreover, the IL-1β-induced downregulation of Collagen II, aggrecan, and Sox9 could be ameliorated by Schisandrin A. Mechanistically, Schisandrin A functioned by suppressing MAPK and NF-κB signal pathways. In vivo, Schisandrin A prevented cartilage damage in rat OA model. In conclusion, this study elucidates that Schisandrin A inhibits the IL-1β-induced inflammation and cartilage degradation via suppression of MAPK and NF-κB signal pathways, indicating its potential role in OA therapy.

Schisandra Chinensis Lignans Suppresses the Production of Inflammatory Mediators Regulated by NF-κB, AP-1, and IRF3 in Lipopolysaccharide-Stimulated RAW264.7 Cells

Schisandra Fructus (SF) is a traditional Chinese herb used in the treatment of inflammatory disorders like hepatitis. One of the main anti-inflammatory components of SF is the lignans. However, the underlying anti-inflammatory mechanism of Schisandra Chinensis lignans (SCL) remains unclear. This study aims to investigate the effects of SCL on inflammatory mediators in lipopolysaccharide-stimulated RAW264.7 cells and explore the underlying mechanism. The production of nitric oxide (NO) was determined by Griess reaction. ELISA was used to determine cytokine levels and chemokines secretion. To estimate protein levels and enzyme activities, we employed Western blotting. Nuclear localization of NF-κB, AP-1, and IRF3 was detected using immunofluorescence analyses. The results showed that SCL significantly reduced the release of inflammatory mediators, including NO and PGE2, which may be related to down-regulation of iNOS and COX-2 expression. The production of cytokines and chemokines was suppressed by SCL treatment. SCL also decreased the phosphorylation of IKKα/β, IκB-α, Akt, TBK1, ERK, p38, JNK, NF-κB (p65), AP-1 (c-Jun), and IRF3 in RAW264.7 macrophages activated with LPS. The nuclear protein levels and nuclear translocation of AP-1, NF-κB and IRF3 were suppressed by SCL. These results indicated that SCL suppressed the IKKα/β/NF-κB, MAPKs/AP-1 and TBK1/IRF3 signaling pathways in LPS-stimulated RAW264.7 macrophages.

Schisandrin A prevents oxidative stress-induced DNA damage and apoptosis by attenuating ROS generation in C2C12 cells

The generation of excessive reactive oxygen species (ROS) by oxidative stress has various deleterious effects on cellular constituents. Therefore, the discovery of natural products that can inhibit the production of ROS may be effective in suppressing the onset and treatment of oxidative stress-mediated diseases. Despite the antioxidant efficacy studies on various substances in the genus Schisandra used as traditional medicine, research on the efficacy of schisandrin A, a class of active lignans, remains insufficient. This study was conducted to evaluate the protective effect of schisandrin A on DNA damage and apoptosis induced by hydrogen peroxide (H₂O₂) in C2C12 cells. Results showed that schisandrin A effectively attenuated H₂O₂-induced cytotoxicity and DNA damage, which was related to the blockage of ROS accumulation. Schisandrin A also prevented the decrease in ATP content by H₂O₂ and restored the H₂O₂-induced activation of AMP-activated protein kinase. In addition, schisandrin A prevented the release of H₂O₂-induced cytochrome c into the cytoplasm presumably by inhibiting the loss of mitochondrial membrane potential and the changes in the Bcl-2 family protein expression by H₂O₂. Furthermore, the blocking of H₂O₂-induced apoptosis by schisandrin A was associated with the inhibition of poly (ADP-ribose) polymerase degradation by the inactivation of caspase-3. These results suggest that schisandrin A maintains energy metabolism through the preservation of mitochondrial function while eliminating ROS generated by H₂O₂ in C2C12 cells. Therefore, our data indicate that schisandrin A may have a beneficial effect on the prevention and treatment of diseases associated with apoptosis induced by oxidative stress.

Comparative Effects of Schisandrin A, B, and C on Acne-Related Inflammation

Inflammatory responses induced by Propionibacterium acnes are a major etiological factor in the pathogenesis of acne vulgaris. Schisandrin A, schisandrin B, and schisandrin C are the representative lignans of Schisandra chinensis (Turcz.) Baill. extract. Although anti-inflammatory effects of the lignans have been shown, their effects on acne-related inflammation caused by P. acnes have not been investigated and compared. We pretreated THP-1 human monocytic cells with 5, 10, and 20 μM schisandrin A, B, and C, and stimulated the cells with P. acnes. Schisandrin B and C inhibited the release of inflammatory cytokines at a concentration of 5 μM, while schisandrin A required a concentration of 10 μM to exert the effects. All of the schisandrins decreased the levels of toll-like receptor 2, and schisandrin B and C reduced the intracellular mRNA expression of the receptor gene. We also studied the influence of schisandrins on the MAPK signaling pathway. Schisandrin A suppressed the P. acnes-induced activation of JNK, while exerting only a weak effect on ERK and p38. Schisandrin B exerted a strong effect on p38, a lesser effect on ERK, and almost no effect on JNK. Schisandrin C inhibited the phosphorylation of all three proteins, especially ERK. Furthermore, the three lignans also prevented the nuclear translocation of NF-κB. These results contribute to our understanding of the mechanisms underlying the effects of the three lignans on P. acnes-induced inflammation and suggest that schisandrins might be developed as pharmacological agents for acne therapy.

Identification of active components in Yixinshu Capsule with protective effects against myocardial dysfunction on human induced pluripotent stem cell-derived cardiomyocytes by an integrative approach

Traditional Chinese medicine (TCM) preparations have significant effects on some refractory diseases; however, these compositions are complex and their mechanisms are unknown. Identification of the active components in these preparations is essential. The mortality rate for heart failure (HF) has been increasing in recent years, and myocardial dysfunction (MD) has been proved to be the pathological basis of HF. Yixinshu Capsule (YXSC) is a multi-component oral drug with therapeutic effects on HF. However, the key active components are still unclear. In this study, YXSC intestinal absorption liquid (IAL) was used and 62 compounds were identified by an analytical chemistry approach. Then, a compound - target - function network was established with a bioinformatics analysis tool. Finally, a cell model of MD on human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs) was used to verify the therapeutic effects of the active components of YXSC. Schisandrin A (Sch A) and schisandrin B (Sch B) were demonstrated to be the active components of YXSC by attenuating endothelin-1 (ET-1)-induced contraction dysfunction, brain natriuretic peptide (BNP) content elevation, and the morphological changes of hiPS-CMs. For the first time, our data illustrate the potent protective effects of Sch A and Sch B on ET-1-induced dysfunctional hiPS-CMs and revealed their effective targets and pathways. The integrative approach used in our study was applied to identify active components in TCM preparations and excavate the possible mechanisms.

Schisandrin A suppresses lipopolysaccharide-induced inflammation and oxidative stress in RAW 264.7 macrophages by suppressing the NF-κB, MAPKs and PI3K/Akt pathways and activating Nrf2/HO-1 signaling

Schisandrin A is a bioactive lignan occurring in the fruits of plants of the Schisandra genus that have traditionally been used in Korea for treating various inflammatory diseases. Although the anti-inflammatory and antioxidant effects of lignan analogues similar to schisandrin A have been reported, the underlying molecular mechanisms have remained elusive. In the present study, schisandrin A significantly suppressed the lipopolysaccharide (LPS)-induced production of the key pro-inflammatory mediators nitric oxide (NO) and prostaglandin E2 by suppressing the expression of inducible NO synthase and cyclooxygenase-2 at the mRNA and protein levels in RAW 264.7 macrophages. Furthermore, schisandrin A was demonstrated to reduce the LPS-induced secretion of pro-inflammatory cytokines, including tumor necrosis factor-α and interleukin-1β; this was accompanied by a simultaneous decrease in the respective mRNA and protein levels in the macrophages. In addition, the LPS- induced translocation of nuclear factor-κB (NF-κB), as well as activation of mitogen-activated protein kinases (MAPKs) and phosphatidylinositol‑3 kinase (PI3K)/Akt pathways were inhibited by schisandrin A. Furthermore, schisandrin A significantly diminished the LPS-stimulated accumulation of intracellular reactive oxygen species, and effectively enhanced the expression of NF erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). These results suggested that schisandrin A has a protective effect against LPS-induced inflammatory and oxidative responses in RAW 264.7 cells by inhibiting the NF-κB, MAPK and PI3K/Akt pathways; these effects are mediated, at least in part, by the activation of the Nrf2/HO-1 pathway. Based on these results, it is concluded that schisandrin A may have therapeutic potential for treating inflammatory and oxidative disorders caused by over-activation of macrophages.

Comparative effects of schisandrin A, B, and C on Propionibacterium acnes-induced, NLRP3 inflammasome activation-mediated IL-1β secretion and pyroptosis

Propionibacterium acnes, a common pathogen associated with acne, is also responsible for various surgical infections. Schisandrin A, schisandrin B and schisandrin C, the representative lignans of Schisandra chinensis (Turcz.) Baill. extract, inhibit P. acnes-induced inflammation. However, their effects on P. acnes-induced IL-1β secretion and pyroptosis mediated by NLRP3 inflammasome activation remain unknown. In this study, we compared the effects of schisandrin A, B, and C (Sch A, B, and C) on IL-1β secretion and pyroptosis in P. acnes-infected THP-1 cells. As NLRP3 plays important roles in P. acnes-mediated inflammation and pyroptosis, we also investigated the effects of Schs on P. acnes-induced NLRP3 inflammasome activation by measuring the levels of NLRP3, active caspase-1, and mature IL-1β, and activity of caspase-1. Our results showed that Sch A, B, and C suppressed P. acnes-induced pyroptosis. Further, the three lignans significantly suppressed NLRP3 inflammasome activation, with the following potency: Sch C > Sch B > Sch A. Three lignans also inhibited the production of mitochondrial ROS and ATP release. Additionally, Sch B and C almost completely prevented the efflux of K^+., whereas Sch A had a relatively weak effect. Collectively, our novel findings showed that Sch A, B, and C effectively suppressed IL-1β secretion and pyroptosis by inhibiting NLRP3 inflammasome activation in P. acnes-infected THP-1 cells. Thus, Schs may be promising agents for the treatment of P. acnes-related infections.

Attenuation of cyclosporine A induced nephrotoxicity by schisandrin B through suppression of oxidative stress, apoptosis and autophagy

Cyclosporine A (CsA) is a potent immunosuppressive agent whose clinical usage is limited by nephrotoxicity. Schisandrin B (SchB), isolated from the fruit of Schisandra chinensis, is a natural compound with multiple pharmacological activities that has been shown to attenuate organ injury caused by CsA. Hence, the primary objective of the current study was to evaluate whether SchB has a cytoprotective effect on CsA-induced nephrotoxicity in human proximal tubular epithelial cell line (HK-2). This study demonstrated that pre-incubation of HK-2 cells with 2.5-10.0μM SchB ameliorated CsA induced cytotoxicity caused by oxidative stress as evidenced by reduced levels of intracellular reactive oxygen species (ROS) and LDH release along with increased levels of mitochondrial membrane potential (ΔΨm) and glutathione (GSH). Also, it was demonstrated that nuclear factor erythroid 2-related factor 2 (Nrf2) activation was involved in modulating cellular oxidative stress, where SchB promoted Nrf2 translocation into the nucleus and downstream target gene expression of heme oxygenase-1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO1) and Glutamate-cysteine ligase modifier subunit (GCLM). Additionally, SchB was found to enhance cell survival via reducing apoptosis rate as well as recover the CsA induced blockade of autophagic flux. Collectively, these findings demonstrated that SchB mediated alleviation of CsA induced nephrotoxicity by preventing the accumulation of ROS by way of suppressing oxidative stress, apoptosis and autophagy.

Schisandrin B: A Double-Edged Sword in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a spectrum of liver lesions ranging from hepatic steatosis, nonalcoholic steatohepatitis, hepatic cirrhosis, and hepatocellular carcinoma. The high global prevalence of NAFLD has underlined the important public health implications of this disease. The pathogenesis of NAFLD involves the abnormal accumulation of free fatty acids, oxidative stress, endoplasmic reticulum (ER) stress, and a proinflammatory state in the liver. Schisandrin B (Sch B), an active dibenzooctadiene lignan isolated from the fruit of Schisandra chinensis (a traditional Chinese herb), was found to possess antihyperlipidemic, antioxidant, anti-ER stress, and anti-inflammatory activities in cultured hepatocytes in vitro and in rodent livers in vivo. Whereas a long-term, low dose regimen of Sch B induces an antihyperlipidemic response in obese mice fed a high fat diet, a single bolus high dose of Sch B increases serum/hepatic lipid levels in mice. This differential action of Sch B is likely related to a dose/time-dependent biphasic response on lipid metabolism in mice. The hepatoprotection afforded by Sch B against oxidative stress, ER stress, and inflammation has been widely reported. The ensemble of results suggests that Sch B may offer potential as a therapeutic agent for NAFLD. The optimal dose and duration of Sch B treatment need to be established in order to ensure maximal efficacy and safety when used in humans.