Platycodin D Ameliorates Type 2 Diabetes-Induced Myocardial Injury by Activating the AMPK Signaling Pathway.

The current study aimed to assess the effectiveness of pharmacological intervention with Platycodin D (PD), a critically active compound isolated from the roots of Platycodon grandiflorum, in mitigating cardiotoxicity in a murine model of type 2 diabetes-induced cardiac injury and in H9c2 cells in vitro. Following oral administration for 4 weeks, PD (2.5 mg/kg) significantly suppressed the elevation of fasting blood glucose (FBG) levels, improved dyslipidemia, and effectively inhibited the rise of the cardiac injury markers creatine kinase isoenzyme MB (CK-MB) and cardiac troponin T (cTnT). PD treatment could ameliorate energy metabolism disorders induced by impaired glucose uptake by activating AMPK protein expression in the DCM mouse model, thereby promoting the GLUT4 transporter and further activating autophagy-related proteins. Furthermore, in vitro experiments demonstrated that PD exerted a concentration-dependent increase in cell viability while also inhibiting palmitic acid and glucose (HG-PA)-stimulated H9c2 cytotoxicity and activating AMPK protein expression. Notably, the AMPK activator AICAR (1 mM) was observed to upregulate the expression of AMPK in H9c2 cells after high-glucose and -fat exposure. Meanwhile, we used AMPK inhibitor Compound C (20 µM) to investigate the effect of PD activation of AMPK on cells. In addition, the molecular docking approach was employed to dock PD with AMPK, revealing a binding energy of -8.2 kcal/mol and indicating a tight interaction between the components and the target. PD could reduce the expression of autophagy-related protein p62, reduce the accumulation of autophagy products, promote the flow of autophagy, and improve myocardial cell injury. In conclusion, it has been demonstrated that PD effectively inhibits cardiac injury-induced type 2 diabetes in mice and enhances energy metabolism in HG-PA-stimulated H9c2 cells by activating the AMPK signaling pathway. These findings collectively unveil the potential cardioprotective effects of PD via modulation of the AMPK signaling pathway.

Platycodin D facilitates antiviral immunity through inhibiting cytokine storm via targeting K63-linked TRAF6 ubiquitination.

Influenza virus infection is a worldwide challenge that causes heavy burdens on public health. The mortality rate of severe influenza patients is often associated with hyperactive immunological abnormalities characterized by hypercytokinemia. Due to the continuous mutations and the occurrence of drug-resistant influenza virus strains, the development of host-directed immunoregulatory drugs is urgently required. Platycodon grandiflorum is among the top 10 herbs of traditional Chinese medicine used to treat pulmonary diseases. As one of the major terpenoid saponins extracted from Platycodon grandiflorum, Platycodin D (PD) has been reported to play several roles, including anti-inflammation, analgesia, anti-cancer, hepatoprotection, and immunoregulation. However, the therapeutic roles of PD to treat influenza virus infection remains unknown. Here, we show that PD can protect the body weight loss in severely infected influenza mice, alleviate lung damage, and thus improve the survival rate. More specifically, PD protects flu mice via decreasing the immune cell infiltration into lungs and downregulating the overactivated inflammatory response. Western blot and immunofluorescence assays exhibited that PD could inhibit the activation of TAK1/IKK/NF-κB and MAPK pathways. Besides that, CETSA, SPR and immunoprecipitation assays indicated that PD binds with TRAF6 to decrease its K63 ubiquitination after R837 stimulation. Additionally, siRNA interference experiments exhibited that PD could inhibit the secretion of IL-1ß and TNF-α in TRAF6-dependent manner. Altogether, our results suggested that PD is a promising drug candidate for treating influenza. Our study also offered a scientific explanation for the commonly used Platycodon grandiflorum in many anti-epidemic classic formulas. Due to its host-directed regulatory role, PD may serve as an adjuvant therapeutic drug in conjunction with other antiviral drugs to treat the flu.

Platycodin D Ameliorates Cognitive Impairment in Type 2 Diabetes Mellitus Mice via Regulating PI3K/Akt/GSK3ß Signaling Pathway.

Objectives: The aim of this study was to investigate the ameliorative effect of platycodin D (PD) on cognitive dysfunction in type 2 diabetes mellitus (T2DM) and its potential molecular mechanisms of action in vivo and in vitro. Materials and methods: An animal model of cognitive impairment in T2DM was established using a single intraperitoneal injection of streptozotocin (100 mg/kg) after 8 weeks of feeding a high-fat diet to C57BL/6 mice. In vitro, immunofluorescence staining and Western blot were employed to analyze the effects of PD on glucose-induced neurotoxicity in mouse hippocampal neuronal cells (HT22). Results: PD (2.5 mg/kg) treatment for 4 weeks significantly suppressed the rise in fasting blood glucose in T2DM mice, improved insulin secretion deficiency, and reversed abnormalities in serum triglyceride, cholesterol, low-density lipoprotein, and high-density lipoprotein levels. Meanwhile, PD ameliorated choline dysfunction in T2DM mice and inhibited the production of oxidative stress and apoptosis-related proteins of the caspase family. Notably, PD dose-dependently prevents the loss of mitochondrial membrane potential, promotes phosphorylation of phosphatidylinositol 3 kinase and protein kinase B (Akt) in vitro, activates glycogen synthase kinase 3ß (GSK3ß) expression at the Ser9 site, and inhibits Tau protein hyperphosphorylation. Conclusions: These findings clearly indicated that PD could alleviate the neurological damage caused by T2DM, and the phosphorylation of Akt at Ser473 may be the key to its effect.

Analysis of gut microbiota metabolites of platycodin D and activity verification.

As the main saponin component of Platycodon grandiflorum A.DC, Platycodin D has been reported to have an anti-obesity effect. Due to poor oral absorption, the intestinal microflora usually transforms saponins into potential bioactive substances. In this study, we profiled the metabolic changes of platycodin D by incubating it with intestinal microflora extracted from mice feces subjected to either a standard control diet or a high-fat diet. A UPLC-LTQ-Orbitrap-MS method was used for rapid analysis of the metabolic profile of platycodin D. A total of 10 compounds were identified 9 of which were assessed to be metabolized by intestinal microflora. Dehydroxylation and deglycosylation were the major metabolic process of platycodin D. The metabolic profile of platycodin D biotransformed by intestinal microflora was elucidated based on the metabolite information. Platycodin D and its metabolites had anti-inflammatory effects in LPS-stimulated RAW 264.7 cells. Only platycodin D could alleviate lipid accumulation in FFA-treated HepG2 cells.

Platycodin D2 enhances P21/CyclinA2-mediated senescence of HCC cells by regulating NIX-induced mitophagy.

BACKGROUND: Hepatocellular carcinoma (HCC) cells usually show strong resistance to chemotherapy, which not only reduces the efficacy of chemotherapy but also increases the side effects. Regulation of autophagy plays an important role in tumor treatment. Cell senescence is also an important anti-cancer mechanism, which has become an important target for tumor treatment. Therefore, it is of great clinical significance to find anti-HCC drugs that act through this new mechanism. Platycodin D2 (PD2) is a new saponin compound extracted from the traditional Chinese medicine Platycodon grandiflorum. PURPOSE: Our study aimed to explore the effects of PD2 on HCC and identify the underlying mechanisms. METHODS: First, the CCK8 assay was used to detect the inhibitory effect of PD2 on HCC cells. Then, different pathways of programmed cell death and cell cycle regulators were measured. In addition, we assessed the effects of PD2 on the autophagy and senescence of HCC cells by flow cytometry, immunofluorescence staining, and Western blotting. Finally, we studied the in vivo effect of PD2 on HCC cells by using a mouse tumor-bearing model. RESULTS: Studies have shown that PD2 has a good anti-tumor effect, but the specific molecular mechanism has not been clarified. In this study, we found that PD2 has no obvious toxic effect on normal hepatocytes, but it can significantly inhibit the proliferation of HCC cells, induce mitochondrial dysfunction, enhance autophagy and cell senescence, upregulate NIX and P21, and downregulate CyclinA2. Gene silencing and overexpression indicated that PD2 induced mitophagy in HCC cells through NIX, thereby activating the P21/CyclinA2 pathway and promoting cell senescence. CONCLUSIONS: These results indicate that PD2 induces HCC cell death through autophagy and aging. Our findings provide a new strategy for treating HCC.

Platycodin D induces apoptosis via regulating MAPK pathway and promotes autophagy in colon cancer cell.

Platycodin D (PD) is the main component of triterpene saponins found in Platycodi radix. In this study, we observed a decrease in cell viability, an increase in apoptotic bodies, and an increase in the rate of apoptosis. Also, we observed an increase in cleaved PARP and Bax, a decrease in Bcl-2, and p-ERK, and an increase in p-p38 and p-JNK. Furthermore, a change in cell viability and the expression of p-p38, Bax, and Bcl-2 using the p38 inhibitor revealed a decrease in p-p38 and Bax and an increase in Bcl-2 in the inhibitor treatment group. In addition, we observed an increase in vacuole formation through morphological changes and an increase in acidic vesicular organelles (AVOs). We also observed an increase in the expression of beclin 1, LC 3-I, and -II. There was no significant decrease in cell viability in the group treated with 3-MA, but a decrease in cell viability was noted in the group treated with HCQ. HCQ treatment resulted in an increase in Bax and a decrease in Bcl-2. These findings reveal that in HT-29 colon cancer cells, PD induces apoptosis through the MAPK pathway, thereby exerting anticancer effects. Moreover, autophagy caused by PD inhibits apoptosis by protecting the cells.

Platycodin D inhibits diabetic retinopathy via suppressing TLR4/MyD88/NF-κB signaling pathway and activating Nrf2/HO-1 signaling pathway.

Diabetic retinopathy (DR) is one of the most frequently occurring diabetic complications associated with inflammation and oxidative stress. Platycodin D (PLD) is a bio-active saponin that has been reported to exhibit anti-inflammation, anti-oxidative, and antidiabetic activities. Therefore, we speculated the protective effects of PLD on DR in the present study. Our results demonstrated that PLD attenuated high glucose (HG)-induced inflammation, as evidenced by decreased production of TNF-α, IL-1ß, IL-6. The HG-induced oxidative stress was prevented by PLD with decreased ROS production and malondialdehyde (MDA) level, as well as increased activities of superoxide dismutase and glutathione (GSH). In addition, treatment of PLD significantly decreased the apoptotic rate in HG-induced ARPE-19 cells. The HG-caused increases in expression of bax and cleaved capsase-3, as well a decrease in bcl-2 expression were attenuated by PLD. Furthermore, PLD suppressed the activation of TLR4/MyD88/NF-κB and enhanced the activation of Nrf2/HO-1 pathway in HG-induced ARPE-19 cells. Additionally, overexpression of TLR4 attenuated the anti-inflammatory, while knockdown of Nrf2 reversed the anti-oxidative and anti-apoptotic activities of PLD in HG-stimulated ARPE-19 cells. Furthermore, PLD attenuates retinal damage in DR rats. Finally, we demonstrated that PLD weakened the TLR4/MyD88/NF-κB p65 pathway and promoted the Nrf2/HO-1 pathway in vivo. Taken together, these findings indicated that PLD exerted protective effects against DR, which were attributed to the regulation of TLR4/MyD88/NF-κB and Nrf2/HO-1 signaling pathways.

Platycodin D ameliorates ammonia-induced pulmonary fibrosis by repressing TGF-ß1-mediated extracellular matrix remodeling.

Ammonia can induce pulmonary fibrosis in humans and animals. Platycodin D (PLD) possesses various bioactive activities including anti-fibrotic properties. In this study, we aimed to explore the activity and mechanism of PLD in pulmonary fibrosis induced by ammonia. The mouse model of ammonia-induced lung fibrosis was established, and the role of PLD was assessed by H&E and Masson's trichrome staining. The differentially expressed genes (DEGs) were identified by RNA-seq and subjected to GO and KEGG pathway analyses. BEAS-2B cells were treated with NH4 Cl alone or along with PLD. Results showed that PLD attenuated ammonia-induced pulmonary inflammation and fibrosis in vivo. The extracellular matrix (ECM)-receptor interaction pathway was predicted as a prominent pathway underlying the anti-fibrotic function of PLD. In ammonia-induced mouse models and NH4 Cl-treated BEAS-2B cells, PLD could repress the activation of the TGF-ß1 pathway. By incubating lung fibroblast HFL1 cells with the conditioned medium of BEAS-2B cells treated with NH4Cl alone or along with PLD, PLD was confirmed to attenuate NH4 Cl-induced ECM deposition in HFL1 cells. Our findings demonstrate that PLD exerts a protective function in ammonia-induced pulmonary fibrosis by repressing TGF-ß1-mediated ECM remodeling, suggesting the potential therapeutic value of PLD in this disease.

[Platycodin D improves pulmonary fibrosis in mice by down-regulating TRPC6 expression and reducing ROS production in lung fibroblasts].

OBJECTIVE: To assess the effect of platycodin D (PD) for alleviating pulmonary fibrosis in mice and explore the underlying mechanism. METHODS: C57BL/6J mouse models of pulmonary fibrosis induced by bleomycin injection into the airway were treated with daily intragastric administration of 10 mg/kg PD for 28 days. The changes of pulmonary fibrosis and the expression and distribution of transient receptor potential cation channel subfamily C member 6 (TRPC6) were evaluated with immunohistochemistry, HE staining and Sirius Red staining. Western blotting was used to detect α-SMA expression in the lung tissues of the mice. Primary cultures of mouse lung fibroblasts were pretreated with PD (2.5, 5.0, and 10 µmol/L) or larixyl acetate (LA; 10 µmol/L) before exposure to 10 ng/mL transforming growth factor-ß1 (TGF-ß1), and the changes in cell survival rate, expressions of collagen Ⅰ, α-SMA and TRPC6, reactive oxygen species (ROS) production, mitochondrial membrane potential, and cell proliferation capacity were assessed. Network pharmacology analysis was performed to explore the mechanism by which PD alleviated pulmonary fibrosis. RESULTS: PD treatment significantly alleviated pulmonary fibrosis and reduced α-SMA expression in BLM-induced mouse models (P<0.05). In TGF-ß1-induced primary mouse lung fibroblasts, PD effectively inhibited the cell proliferation, reduced ROS production (P<0.0001), rescued the reduction of mitochondrial membrane potential (P<0.001), and inhibited the expressions of α-SMA and collagen Ⅰ (P<0.05). Network pharmacology analysis suggested that TRPC6 mediated the effect of PD for alleviating pulmonary fibrosis. Immunohistochemistry showed that PD significantly reduced TRPC6 expression in the lung tissues of BLM-induced mice. In primary mouse lung fibroblasts, PD significantly inhibited TGF-ß1-induced TRPC6 expression (P<0.05), and LA treatment obviously lowered the expression levels of TRPC6, α-SMA and collagenⅠ (P<0.05). CONCLUSION: PD alleviated pulmonary fibrosis in mice possibly by down-regulating TRPC6 and reducing ROS production.

Study on the antitussive and expectorant activities and mechanism of platycodin D based on metabolomics method / 药学学报

In this paper, the antitussive and expectorant activity of platycodin D (PD) were studied by constructing a mouse cough induced by concentrated ammonia water and a mouse trachea phenol red excretion model. The mechanism of antitussive and expectorant effect of PD was studied by metabolomics. The animal experiment was approved by the Animal Ethics Committee of Jiangxi University of Chinese Medicine (approval number: JZLLSC-20220739). Then mice were randomly divided into the normal, model, positive drug, PD low-dose, PD medium-dose and PD high-dose group. The antitussive and expectorant effects of PD were evaluated using a cough mouse model induced by concentrated ammonia water and a mouse tracheal phenol red excretion model, respectively. UHPLC-LTQ-Orbitrap-MS was used to identify the metabolites of mouse lung tissue, and multivariate statistical analysis method of orthogonal partial least squares discriminant analysis (OPLS-DA) was used for metabolites profile analysis. The differential metabolites were screened by variable projected importance value (VIP) and t-test results. Pathways for enrichment of differentiated metabolites were analyzed using the MetaboAnalyst platform. The comparative method was applied to analyze the differences in mechanisms of PD, Deapio-platycodin D (DPD) and total platycosides fraction. The results showed that PD at different concentrations could significantly prolong (P < 0.05) the incubation period of cough mice induced by ammonia water, reduce the coughs frequency, and significantly increase (P < 0.05) the amount of phenol red excretion in phenol red excretion model mice. PD could regulate 6 metabolic pathways of phenylalanine, tyrosine and tryptophan biosynthesis, linoleic acid metabolism, phenylalanine metabolism, glycerophospholipid metabolism, and tyrosine metabolism to exert antitussive effect. It could also regulate 8 metabolic pathways of linoleic acid metabolism, glyoxylic acid and dicarboxylic acid metabolism, glycerol phospholipid metabolism, citric acid cycle and arachidonic acid metabolism to exert an expectorant effect. However, only linoleic acid metabolism and glycerophospholipid metabolism could be regulated by the PD, total platycosides fraction and DPD, which may be ascribed to the structural difference of the platycosides and the interaction between platycosides and the intestinal microbiota. Functional analysis showed that these metabolic pathways are closely related to the regulatory mechanisms of anti-inflammatory response, immune function regulation, neurotransmitter release, cell signal transduction, energy metabolism and cell apoptosis. This study shows that PD possesses good antitussive and expectorant activities. In addition, the mechanism difference of PD, total platycosides fraction and DPD imply that the apiose in PD and the interaction between PD and intestinal microbiota could exert an important effect on the antitussive and expectorant mechanism of the platycosides.

Investigation of the response of Platycodongrandiflorus (Jacq.) A. DC to salt stress using combined transcriptomics and metabolomics.

BACKGROUND: Platycodon grandiflorus (Jacq.) A. DC is a famous traditional Chinese medicine in China and an authentic medicine in Inner Mongolia. It has been traditionally used as an expectorant in cough and also has anti-inflammatory and other pharmacological effects. As a homologous plant of medicine and food, P. grandiflorus is widely planted in Northeast China. Soil salinity isa limiting factor for its cultivation. In this study, we comprehensively described the physiological characteristics of P. grandiflorus and combined transcriptomics and metabolomics to study the response of roots of P. grandiflorus to salt stress. RESULTS: Overall, 8,988 differentially expressed genes were activated and significantly altered the metabolic processes. In total, 428 differentially abundant metabolites were affected by salt stress. After moderate and severe salt stress, most of the differentially abundant metabolites were enriched in the L-phenylalanine metabolic pathway. Through the comprehensive analysis of the interaction between key genes and metabolites, the main pathways such as lignin compound biosynthesis and triterpene saponin biosynthesis were completed. The relative content of compounds related to lignin biosynthesis, such as caffeic acid, coniferin, and syringing, increased under salt stress, and the related genes such as PAL, C4H, and the key enzyme gene UGT72E2 were activated to adapt to the salt stress. Platycodon saponin is one of the major triterpene saponins in P. grandiflorus, and Platycodin D is its most abundant major bioactive component. Under severe salt stress, Platycodin D level increased by nearly 1.77-fold compared with the control group. Most of the genes involved insynthetic pathway of Platycodin D, such as HMGCR, GGPS, SE, and LUP, were upregulated under salt stress. CONCLUSION: Salt stress led to a decrease in the biomass and affected the activities of antioxidant enzymes and contents of osmotic regulators in the plant. These results provided not only novel insights into the underlying mechanisms of response of P. grandiflorus to salt stress but also a foundation for future studies on the function of genes related to salt tolerance in the triterpenoid saponin biosynthesis pathway.

Optimization of extraction condition for platycodin D from Platycodon grandiflorum root and verification of its biological activity.

Platycosides, major components of Platycodon grandiflorum (PG) extract, have been implicated in a wide range of biological effects. In particular, platycodin D (PD) is a well-known main bioactive compound of Platycosides. Despite the biological significance of PD, optimization of extract condition for PD from PG root has not been well investigated. Here, we established the optimum extraction condition as ethanol concentration of 0%, temperature of 50°C, and extraction time of 11 h to obtain PD-rich P. grandiflorum extract (PGE) by using response surface methodology (RSM) with Box-Behnken design (BBD). The 5.63 mg/g of PD was extracted from the PG root in optimum condition, and this result was close to the predicted PD content. To analyze the biological activity of PGE related to mucin production, we demonstrated the inhibitory effect of PGE on PMA-induced hyperexpression of MUC5AC as well as ERK activation, a signal mediator of MUC5AC expression. Moreover, we showed that PGE had expectorant activity in mice. These results indicated that PGE had sufficient functions as a potential mucoregulator and expectorant for treating diverse airway diseases. Additionally, we confirmed that PGE had antioxidant activity and inhibited LPS-induced proinflammatory cytokines, TNF-α, and IL-6. Taken together, PGE derived from novel optimizing conditions showed various biological effects, suggesting that PGE could be directly applied to the food industry as food material having therapeutic and preventive potential for human airway diseases.

Platycodin D induces neutrophil apoptosis by downregulating PD-L1 expression to inhibit breast cancer pulmonary metastasis.

During breast cancer development, programmed cell death 1 ligand 1 (PD-L1) overexpression in neutrophils leads to delayed apoptosis and promotes neutrophil hyperproliferation in the lung to form a premetastatic niche, which is beneficial for pulmonary metastasis. Platycodin D (PlaD), a triterpenoid saponin with known anti-inflammatory and antitumor effects, has been reported to downregulate PD-L1 expression. This study aimed to investigate the inhibitory effect of PlaD on neutrophil PD-L1 in 4 T1 tumor-bearing mice and the potential mechanism of breast cancer pulmonary metastasis. In this study, the orthotopic 4 T1 murine mammary carcinoma model was administered 10 and 20 mg/kg PlaD by gavage. PlaD reduced the excess neutrophils and decreased their high migratory capacity in bone marrow, peripheral blood and lung tissue in the premetastatic period, thereby effectively inhibiting tumor growth and pulmonary metastasis. Moreover, PlaD inhibited the phosphatidylinositol-3-kinase (PI3K)/Akt pathway by decreasing the expression of PD-L1 in neutrophils and promoted neutrophil apoptosis. In vitro, PlaD treatment decreased the viability and inhibited migration of neutrophil-like dHL-60 in a dose-dependent manner. Similarly, PlaD inhibited the increase in PD-L1 induced by IFN-γ stimulation and subsequently induced apoptosis in dHL-60 cells. In conclusion, the administration of PlaD inhibited the PI3K/Akt signaling pathway by reducing the expression of PD-L1 in neutrophils. PlaD promoted neutrophil apoptosis, thereby inhibiting the establishment of a premetastatic niche and ultimately blocking the development of pulmonary metastasis.

Platycodin D inhibits glioblastoma cell proliferation, migration, and invasion by regulating DEPDC1B-mediated epithelial-to-mesenchymal transition.

BACKGROUND: Platycodin D (PD) is a potent bioactive constituent in the medicinal herb Platycodon grandiflorum. It has shown anticancer properties, particularly against glioblastoma (GB) and other human malignancies. DEPDC1B (DEP domain-containing protein 1B) is an oncogene associated with epithelial-mesenchymal transition (EMT). It is highly expressed in GB and correlated with tumor grade and patient prognosis. In this study, we investigated whether the antiglioma effect of PD was associated with downregulation of DEPDC1B. METHODS: Gene expression and clinical data were obtained from the China Glioma Genome Atlas and The Cancer Genome Atlas databases for glioma samples. In vitro experiments were conducted using Cell Counting Kit-8 and Transwell assays to assess the impact of PD on the proliferation, migration, and invasion of GB cells. mRNA and protein expression was evaluated using real-time polymerase chain reaction and western blotting, respectively. RESULTS: PD exerted inhibitory effects on the proliferation and motility of GB cells. PD downregulated DEPDC1B protein as well as several markers associated with EMT, namely N-cadherin, vimentin, and Snail. The suppressive effects of PD were enhanced when DEPDC1B was knocked down in GB cells, while overexpression of DEPDC1B in cells reversed the inhibitory effects of PD. CONCLUSION: PD exerts an antiglioma effect by regulating DEPDC1B-mediated EMT.

A safety study on ultra­high or moderate static magnetic fields combined with platycodin D against lung cancer.

Due to the serious side effects of chemotherapy drugs against lung cancer, and the antitumor properties and high safety of magnetic fields, the present study combined moderate or ultra-high intensity statics magnetic fields (SMFs) with platycodin D (PD) to explore the antitumor efficiency and biosafety. The antitumor effects of PD with or without moderate and ultra-high SMFs on A549 cells bearing mice were compared. Mouse body weight, food/water intake, hematology routine, blood biochemistry, tumor weight and tissues hematoxylin and eosin (H&E) staining were examined. Behavior was measured using the elevated plus maze, open field and vital signs tests. The combined targets of PD and SMFs were detected using RNA-sequencing (RNA-seq). The results showed that the antitumor effect of 22 Tesla (T) SMF group was 3.6-fold higher compared with that of the 2 mg/kg PD group (tumor growth inhibition=10.08%), while the antitumor effect of 150 mT SMF was only 1.56-fold higher compared with that of PD. Although PD reduced the food intake, there was no significant difference in body weight, water intake or food consumption among PD and SMF groups. Behavioral results indicated that PD ameliorated dysphoria in mice, but SMFs reduced this effect. However, no significant abnormalities were found in routine blood, blood biochemistry test, H&E staining or organ index, except renal index which was reduced by PD with or without SMFs. RNA-sequencing (RNA-seq) demonstrated that SMFs and PD synergistically targeted the expression of genes associated with tumor growth, inflammation and neurological disease. The present study showed the antitumor efficacy and biosafety of moderate or ultra-high SMF combined with PD, which exhibited only few side effects in the treatment of lung cancer, thus supporting further research for the clinical application of magnetic fields.

Platycodin D induces apoptotic cell death through PI3K/AKT and MAPK/ERK pathways and synergizes with venetoclax in acute myeloid leukemia.

Acute myeloid leukemia (AML) is a highly heterogeneous and rapidly progressive hematopoietic neoplasm characterized by frequent relapses and variable prognoses. The development of new treatment options, therefore, is of crucial importance. Platycodin D (PD) is a triterpenoid saponin, extracted from the roots of the traditional Chinese herbal medicine Platycodon grandiflorum (Jacq.) A. DC., which has been reported to exhibit therapeutic potential against a broad range of cancers. Although the effects of PD on AML remain unclear, in the present study, we observed a concentration-dependent reduction in the viability of multiple human AML cell lines in response to treatment with PD. In addition to triggering mitochondria-dependent apoptosis via the upregulation of BAK and BIM, treatment with PD also induced cell cycle arrest at the G0/G1 phase. Western blot analyses revealed marked suppression of the phosphorylation of protein kinase B (AKT), glycogen synthase kinase-3ß, ribosomal protein S6, and extracellular signal-regulated kinase (ERK) by PD, in turn implying the participation of the phosphoinositide 3-kinase (PI3K)/AKT and mitogen-activated protein kinase (MAPK)/ERK pathways. Pre-incubation with LY294002, MK2206, AR-A014418, or U0126 was consistently found to significantly aggravate PD-induced inhibition of viability. Additionally, PD combined with the B-cell lymphoma 2 (BCL2) inhibitor venetoclax elicited synergistically enhanced cytotoxic effects. The anti-leukemic activity of PD was further validated using primary samples from de novo AML patients. Given the results of the present study, PD may be a potent therapeutic candidate for the treatment of AML.

Platycodin D represses ß-catenin to suppress metastasis of cetuximab-treated KRAS wild-type colorectal cancer cells.

Cetuximab, an epidermal growth factor receptor (EGFR) inhibitor, is extensively used for clinical therapy in KRAS wild-type colorectal cancer (CRC) patients. However, some patients still cannot get benefit from the therapy, because metastasis and resistance occur frequently after cetuximab treatment. New adjunctive therapy is urgently needed to suppress metastasis of cetuximab-treated CRC cells. In this study, we used two KRAS wild-type CRC cells, HT29 and CaCo2, to investigate whether platycodin D, a triterpenoid saponin isolated from Chinese medicinal herb Platycodon grandifloras, is able to suppress the metastasis of cetuximab-treated CRC. Label-free quantitative proteomics analyses showed that platycodin D but not cetuximab significantly inhibited expression of ß-catenin in both CRC cells, and suggested that platycodin D counteracted the inhibition effect of cetuximab on cell adherence and functioned in repressing cell migration and invasion. Western blot results showed that single platycodin D treatment or combined platycodin D and cetuximab enhanced inhibition effects on expressions of key genes in Wnt/ß-catenin signaling pathway, including ß-catenin, c-Myc, Cyclin D1 and MMP-7, compared to single cetuximab treatment. Scratch wound-healing and transwell assays showed that platycodin D combined with cetuximab suppressed migration and invasion of CRC cells, respectively. Pulmonary metastasis model of HT29 and CaCo2 in nu/nu nude mice consistently showed that combined treatment using platycodin D and cetuximab inhibited metastasis significantly in vivo. Our findings provide a potential strategy to inhibit CRC metastasis during cetuximab therapy by addition of platycodin D.

Platycodin D relieves rheumatoid arthritis by promoting apoptosis of mitochondria to inhibit activation of hedgehog pathway.

Rheumatoid arthritis (RA) displays very similar characteristics to those of tumor cells, platycodin D (PD) is a triterpenoid saponin abundant in Platycodon grandiflorum (PG), plays an important role in the inhibition of tumor growth. Our previous experiments confirmed that PD inhibited MH7A cell proliferation and migration, but it's possible mechanism remain unclear. This study aimed to reveal the mechanism of PD on RA, based on network pharmacology analysis. Rat of CIA was treated with the different doses PD. The arthritis score and paw volume were evaluated, ankle imaging changes were observed via myosseous ultrasound, all rats were anaesthetized by intraperitoneal injection of 25% urethane (1 mL/100 g), and ankle histopathology was observed using hematoxylin and eosin (HE) staining. Cell (MH7A) Counting Kit 8 (CCK8) was used to measure cell activity, and JC-1 assay kit and flow cytometry were employed to examine the cell mitochondrial membrane potential and apoptosis. The expression levels of Sonic hedgehog (Shh) signaling pathway-related proteins were observed by Western blotting. Cell inflammation levels of tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6 being determined via enzyme-linked immunoassay ELISA and q-PCR. In total, the saponin PD significantly improves joint synovium inflammation and apoptosis in CIA rats. The activity of administered MH7A was significantly inhibited, the mitochondrial membrane potential decreased, the expression level of the Shh signaling pathway-related protein SuFu increased, the expression levels of SHh and Gli decreased, and cell serum levels of TNF-a and IL-6 decreased significantly. Therefore, PD exhibits therapeutic potential for synovial hyperplasia in RA.

Platycodin D inhibits HFD/STZ-induced diabetic nephropathy via inflammatory and apoptotic signaling pathways in C57BL/6 mice.

ETHNOPHARMACOLOGICAL RELEVANCE: The dried root of Platycodon grandiflorum (Jacq.) A.DC. (PG) is a traditional herb used in Asian countries and is widely used in formulas for the treatment of diabetes. Platycodin D (PD) is one of the most important components of PG. AIM OF THE STUDY: This study aimed to investigate the improvement effects and regulatory mechanisms of PD on kidney injury in a high-fat diet (HFD) combined with streptozotocin (STZ)-induced diabetic nephropathy (DN). MATERIALS AND METHODS: Model mice were treated with oral gavage of the PD (2.5, 5 mg/kg) for 8 weeks. Determination of serum lipid and renal function-related indexes creatinine (CRE), and blood urea nitrogen (BUN) levels in mice, and histopathological section analysis of kidney. Molecular docking and molecular dynamics were utilized to study the binding ability of PD to target NF-κB and apoptosis signaling pathway-related proteins. Moreover, Western blot was used to test the expressions of NF-κB and apoptosis-related proteins. Vitro experiments were performed to validate the related mechanisms using RAW264.7 cells and HK2 cells cultured by high glucose. RESULTS: In vivo experiments, the administration of PD (2.5 and 5.0 mg/kg) reduced fasting blood glucose (FBG) and homeostasis model assessment of insulin resistance (HOMA-IR) levels in DN mice, while lipid levels and renal function were significantly improved. Furthermore, PD significantly inhibited the development of DN in the model mice by regulating NF-κB and apoptotic signaling pathways, reduced the abnormal elevation of serum inflammatory factors TNF-α and IL-1ß, and repaired renal cell apoptosis. In vitro experiments, NF-κB inhibitor ammonium pyrrolidine dithiocarbamate (PDTC) was used to confirm that PD can alleviate high glucose-induced inflammation in RAW264.7 cells and inhibit the release of inflammatory factors. And in HK2 cell experiments, it was verified that PD can inhibit ROS generation, reduce the loss of JC-1 and suppress HK2 cell injury by regulating NF-κB and apoptotic pathways. CONCLUSIONS: These data suggested that PD has the potential to prevent and treat DN and is a promising natural nephroprotective agent.

The pharmacology and mechanisms of platycodin D, an active triterpenoid saponin from Platycodon grandiflorus.

Chinese doctors widely prescribed Platycodon grandiflorus A. DC. (PG) to treat lung carbuncles in ancient China. Modern clinical experiences have demonstrated that PG plays a crucial role in treating chronic pharyngitis, plum pneumonia, pneumoconiosis, acute and chronic laryngitis, and so forth. Additionally, PG is a food with a long history in China, Japan, and Korea. Furthermore, Platycodin D (PLD), an oleanane-type triterpenoid saponin, is one of the active substances in PG. PLD has been revealed to have anti-inflammatory, anti-viral, anti-oxidation, anti-obesity, anticoagulant, spermicidal, anti-tumor etc., activities. And the mechanism of the effects draws lots of attention, with various signaling pathways involved in these processes. Additionally, research on PLD's pharmacokinetics and extraction processes is under study. The bioavailability of PLD could be improved by being prescribed with Glycyrrhiza uralensis Fisch. or by creating a new dosage form. PLD has been recently considered to have the potential to be a solubilizer or an immunologic adjuvant. Meanwhile, PLD was discovered to have hemolytic activity correlated. PLD has broad application prospects and reveals practical pharmacological activities in pre-clinical research. The authors believe that these activities of PLD contribute to the efficacy of PG. What is apparent is that the clinical translation of PLD still has a long way to go. With the help of modern technology, the scope of clinical applications of PLD is probable to be expanded from traditional applications to new fields.