Platycodon Research Articles

Molecular characterization of Fusarium solani causing stem and root rot disease of balloon flower (Platycodon grandiflorus) in Viet Nam

The most significant issue affecting balloon flower (Platycodon grandiflorus) in Vietnam’s mountainous provinces is stem and root rot disease. The purpose of this study was to identify the causal fungus Fusarium solani of balloon flower planted in Lao Cai province. F. solani’s identity was confirmed through DNA sequencing and phylogenetic analyses based on ITS sequences. PDA was the most suitable medium for F. solani growth and development of the three semi-solid media tested (CA, PDA, and CDA). The optimal temperature and pH conditions for its growth ranged from 25-30 °C with a maximum growth rate of 25 °C and pH 5.5-7.0 with a maximum growth rate of 6.5. This is the first report of F. solani causing balloon flower stem and root rot in Vietnam.

Lobetyolin, a Q-marker isolated from Radix Platycodi, exerts protective effects on cisplatin-induced cytotoxicity in HEK293 cells.

This study investigated the protective effect of lobetyolin (LBT), a Q-marker isolated from the roots of Platycodon grandiflorum (Radix Platycodi), against cisplatin-induced cytotoxicity in human embryonic kidney (HEK293) cells. Results showed that LBT at 20μM significantly prevented cisplatin-induced cytotoxicity by improving the viability of HEK293 cells, decreasing levels of MDA, and decreasing GSH content triggered by cisplatin. It also suppressed reactive oxygen species (ROS) levels. Molecular docking analysis revealed a strong binding affinity between LBT and the NF-κB protein, with a docking fraction of -6.5kcal/mol. These results provide compelling evidence suggesting a potential link between the visualization analysis of LBT and its protective mechanism, specifically implicating the NF-κB signaling pathway. LBT also reduced the expression level of tumor necrosis factor-alpha (TNF-α), phosphorylation NF-κB and IκBα in HEK293 cells which were increased by cisplatin exposure, leading to inhibition of inflammation. Furthermore, western blotting showed that LBT antagonized the up-regulation of Bax, cleaved caspase 3, 8, and 9 expression and inhibited the MAPK signaling pathway by down-regulating phosphorylation JNK, ERK, and p38, partially ameliorating cisplatin-induced cytotoxicity in HEK293 cells. Therefore, these results indicate that LBT has potentially protected renal function by inhibiting inflammation and apoptosis.

Qingjin Huatan decoction protects mice against influenza a virus pneumonia via the chemokine signaling pathways

Ethnopharmacological relevanceQingjin Huatan Decoction (QJHTT) consists of 11 herbal medicines: Scutellaria baicalensis Georgi, Gardenia jasminoides J.Ellis, Platycodon grandiflorus (Jacq.) A.DC., Ophiopogon japonicus (Thunb.) Ker Gawl., Morus alba L., Fritillaria thunbergii Miq., Anemarrhena asphodeloides Bunge, Trichosanthes kirilowii Maxim., Citrus reticulata Blanco, Poria cocos (Schw.) Wolf, and Glycyrrhiza uralensis Fisch. As a traditional compound Chinese medicinal formula, QJHTT has been used for more than 400 years in China. Historically, it was used to treat respiratory diseases and had shown beneficial clinical results for diseases related to lung inflammation. Aim of the studyTo investigate the therapeutic effect of QJHTT on influenza A virus (IAV) pneumonia in mice and explore its possible mechanism of action. Materials and methodsThe components in QJHTT were analyzed by UPLC-Q-TOF-MS and some antiviral active components reported in the literature were determined and quantified by HPLC. The protective effects of QJHTT were investigated using lethal and sublethal doses (2 LD50 or 0.8 LD50 viral suspension, separately) of H1N1-infected mice. Mortality and lung lesions in H1N1-infected mice were used to evaluate the efficacy of QJHTT. The potential mechanism of QJHTT in the treatment of viral pneumonia was determined at the gene level by RNA sequencing and validated by qRT-PCR. Following this, the changes in protein levels of JAK2/STAT3 were analyzed since it is a key downstream target of the chemokine signaling pathways. Preliminary elucidation of the mechanism of QJHTT to protect mice against IAV pneumonia through this pathway was conducted. ResultsIn this study, 12 antiviral active constituents including baicalin, geniposide, and mangiferin were identified from QJHTT. In vivo treatment of QJHTT reduced the virus titers of lung tissue significantly and improved the survival rate, lung index, and pulmonary histopathological changes; additionally, a reduction in the serum levels of TNF-α, IL-1β, IL-6, and IFN-γ inflammatory factors in H1N1-infected mice was observed. RNA-seq analysis and qRT-PCR showed that QJHTT primarily reversed the activities CCL2, CCL7, CCR1, and other chemokines and their reception-related genes, suggesting that QJHTT may produce disease-resistant pneumonia by inhibiting the downstream JAK2/STAT3 pathway. Western blot analysis confirmed that QJHTT effectively reduced the protein levels of JAK2, STAT3, and related phosphorylated products in the lung tissue of H1N1-infected mice. ConclusionsOur results indicated that QJHTT alleviated IAV pneumonia in mice by regulating related chemokines and their receptor-related genes in lung tissue, thereby inhibiting JAK2/STAT3 pathway. This could pave way for the design of novel therapeutic strategies to treat viral pneumonia.

Protective effect of Platycodon grandiflorus polysaccharide on apoptosis and mitochondrial damage induced by pseudorabies virus in PK-15 cells.

Previous studies have confirmed that Platycodon grandiflorus polysaccharide (PGPSt) has the effects of regulating immunity and anti-apoptosis, but its effect on mitochondrial damage and apoptosis caused by PRV infection is still unclear. In this research, the effects of PGPSt on the cell viability, mitochondria morphology, mitochondrial membrane potential and apoptosis caused by PRV based on PK-15 cells were respectively examined by CCK-F assay, Mito-Tracker Red CMXRos, JC-1 staining method and Western blot etc. CCK-F test results showed that PGPSt had a protective effect on the decrease of cell viability caused by PRV. The results of morphological observation found that PGPSt can improve mitochondrial morphology damage, mitochondrial swelling and thickening, and cristae fracture. Fluorescence staining test results showed that PGPSt alleviated the decrease of mitochondrial membrane potential and apoptosis in infected cells. The expression of apoptosis-related proteins showed that PGPSt down-regulated the expression of the pro-apoptotic protein Bax and up-regulated the expression of the anti-apoptotic protein Bcl-2 in infected cells. These results indicated that PGPSt protected against PRV-induced PK-15 cell apoptosis by inhibiting mitochondrial damage.

An evaluation of the qualitative superiority of the Mongolian medicinal herb hurdan-tsagaan (Platycodi Radix) from five different geographic origins based on anti-inflammatory effects.

The contents and types of the active compounds in medicinal herbs depend greatly on their extraction methods, sources of origin and the modes of cultivation. Platycodon grandiflorus (Jacq.) A.DC. is an ethnic medicinal herb widely cultivated in China, and its dried root, Platycodi Radix (PR), is an important ingredient in herbal formulae for attenuating lung issues in Mongolian medical practice. However, research evaluating the superiority of PR based on harvesting regions is relatively limited. This study aimed to evaluate the qualitative superiority of PR from different regions based on anti-inflammatory effect. A total of three commercial PR samples were obtained from Anguo, Bozhou and Shangluo, and two wild samples were obtained from Chifeng and Hinggan. PR extract (PRE) was prepared by water distillation, and platycodin D content in the extract was examined by HPLC-UVD. An optimal dose of PRE was administered to BALB/c mice with S. pneumoniae pneumonia, and IL-10 and TNF-α levels in lung tissue were examined by ELISA. HepG2 cells were treated with PRE, and an analysis of differentially expressed gene and functional enrichment was performed using an HTS2 assay. The contents of moisture, total ash, crude extract and platycodin D in the raw roots met the quality control requirements outlined in the Chinese Pharmacopoeia (2020 edition). The platycodin D content in the aqueous extract of the roots in descending order was 24.16% in PRE_Shangluo, 22.91% in PRE_Hinggan, 21.41% in PRE_Bozhou, 17.8% in PRE_Chifeng and 15.92% in PRE_Anguo. Furthermore, administration of PREs at an optimal dose of 2.0g/kg resulted in some anti-inflammatory effect in mice with Streptococcus pneumoniae pneumonia, among which PRE_Shangluo administration exhibited a more obvious anti-inflammatory impact as shown by a significant decrease in the plasma white cell count (p<0.05) and IL-10 level elevation and TNF-α reduction in lung tissue (p<0.05) after treatment. In HepG2 cells treated with 100μg/ml of each PRE, PRE_Hinggan and PRE_Shangluo resulted in significant differential expression of genes such as nuclear factor kappa B subunit 1 (NFKB1) and significant enrichment of pathways involved in the immune system, such as PI3K-Akt, MAPK and NF-kappa B signaling pathways. In this study, based on the anti-inflammatory effect, the quality of PR of Shangluo origin was superior to that of PR from the other four regions.

Balloon Flower Root-Derived Extracellular Vesicles: In Vitro Assessment of Anti-Inflammatory, Proliferative, and Antioxidant Effects for Chronic Wound Healing.

Excessive reactive oxygen species (ROS) in wound lesions can lead to oxidative stress and failure of normal wound healing processes, eventually resulting in chronic skin wounds. A multitude of researchers have investigated various natural products with physiological activities, including antioxidant effects, for healing chronic skin wounds. Balloon flower root (BFR), which contains bioactive components such as platycodins, is known for its anti-inflammatory and antioxidant effects. In this study, we isolated BFR-derived extracellular vesicles (BFR-EVs) that possess anti-inflammatory, proliferative, and antioxidant activities via a combination of polyethylene glycol-based precipitation and ultracentrifugation. Our objective was to investigate the potential of BFR-EVs in treating chronic wounds caused by ROS. Despite efficient intracellular delivery, BFR-EVs showed no significant cytotoxicity. In addition, BFR-EVs inhibited the expression of pro-inflammatory cytokine genes in lipopolysaccharide-stimulated RAW 264.7 cells. Furthermore, water-soluble tetrazolium salt-8 assay showed that BFR-EVs had a proliferation-promoting effect on human dermal fibroblasts (HDFs). Scratch closure and transwell migration assays indicated that BFR-EVs could promote the migration of HDFs. When the antioxidant effect of BFR-EVs was evaluated through 2',7'-dichlorodihydrofluorescein diacetate staining and quantitative real-time polymerase chain reaction, the results revealed that BFR-EVs significantly suppressed ROS generation and oxidative stress induced by H2O2 and ultraviolet irradiation. Our findings suggest that BFR-EVs hold the potential as a natural candidate for healing chronic skin wounds.

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 relevanceThe 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 studyThis 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 methodsModel 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. ResultsIn 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-1β, 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. ConclusionsThese data suggested that PD has the potential to prevent and treat DN and is a promising natural nephroprotective agent.

Platycodin D stimulates AMPK activity to inhibit the neurodegeneration caused by reactive oxygen species-induced inflammation and apoptosis.

Alzheimer's disease (AD) was considered to be a neurodegenerative disease that caused cognitive impairment. Reactive Oxidative stress (ROS) was considered to be one of a major cause of the onset and progression of AD. Platycodin D (PD), a representative saponin from Platycodon grandiflorum, has conspicuous antioxidant activity. However, whether PD could protect nerve cell against oxidative injury remains unknown. This study investigated the regulatory effects of PD on neurodegeneration caused by ROS. To determine whether PD could play its own antioxidant role in neuronal protection. First, PD(2.5, 5mg/kg) ameliorated the memory impairment induced by AlCl3 (100mg/kg) combined with D-galactose (D-Gal) (200mg/kg) in mice, using the radial arm maze (RAM) test, and neuronal apoptosis in the hippocampus was evaluated by hematoxylin and eosin staining (HE). Next, the effects of PD (0.5, 1, and 2μM) on okadaic-acid (OA) (40nM) -induced apoptosis and inflammation of HT22cells were investigated. Mitochondrial ROS production was measured by fluorescence staining. The potential signaling pathways were identified through Gene Ontology enrichment analysis. The role of PD in regulating AMP-activated protein kinase (AMPK) was assessed using siRNA silencing of genes and an ROS inhibitor. In vivo, PD improved memory in mice, and recovered the morphological changes of brain tissue and nissl bodies. In vitro experiment, PD increased cell viability (p<0.01; p<0.05;p<0.001), decreased apoptosis (p<0.01), reduced excessive ROS and MDA, rised SOD and CAT content(p<0.01; p<0.05). Morover, it can block the inflammatory response caused by ROS. Be important, PD strengthen antioxidant ability by elevating AMPK activation both in vivo and in vitro. Furthermore, molecular docking suggested a good likelihood of PD-AMPK binding. AMPK activity is vital for the neuroprotective effect of PD, suggesting that PD may be a potential pharmaceutical agent to treat ROS-induced neurodegeneration.

Polygalacin D inhibits the growth of hepatocellular carcinoma cells through BNIP3L-mediated mitophagy and endogenous apoptosis pathways.

Platycodon grandiflorum (Jacq.) A. DC. is a famous medicinal plant commonly used in East Asia. Triterpene saponins isolated from P. grandiflorum are the main biologically active compounds, among which polygalacin D (PGD) has been reported to be an anti-tumor agent. However, its anti-tumor mechanism against hepatocellular carcinoma is unknown. This study aimed to explore the inhibitory effect of PGD in hepatocellular carcinoma cells and related mechanisms of action. We found that PGD exerted significant inhibitory effect on hepatocellular carcinoma cells through apoptosis and autophagy. Analysis of the expression of apoptosis-related proteins and autophagy-related proteins revealed that this phenomenon was attributed to the mitochondrial apoptosis and mitophagy pathways. Subsequently, using specific inhibitors, we found that apoptosis and autophagy had mutually reinforcing effects. In addition, further analysis of autophagy showed that PGD induced mitophagy by increasing BCL2 interacting protein 3 like (BNIP3L) levels.In vivo experiments demonstrated that PGD significantly inhibited tumor growth and increased the levels of apoptosis and autophagy in tumors. Overall, our findings showed that PGD induced cell death of hepatocellular carcinoma cells primarily through mitochondrial apoptosis and mitophagy pathways. Therefore, PGD can be used as an apoptosis and autophagy agonist in the research and development of antitumor agents.

Platycodin D induces proliferation inhibition and mitochondrial apoptosis in diffuse large B-cell lymphoma

Patients with diffuse large B-cell lymphoma (DLBCL) have unsatisfactory outcomes, especially when relapse occurs after initial chemotherapy. Platycodin D (PD), a triterpenoid saponin isolated from the root of Platycodon grandiflorum (Jacq.) A. DC., has demonstrated potent anticancer activities. However, information regarding the effect of PD on malignant lymphoma remains unavailable. In the present study, we showed that PD dose dependently inhibited the viability of a serial of established DLBCL cell lines representing different molecular subtypes, and their sensitivities to PD were comparable. Mitochondrial dysfunction and subsequent intrinsic apoptosis were induced by PD, as indicated by the loss of mitochondrial membrane potential (MMP) and the increase in the percentage of Annexin Ⅴ-positive cells. Mechanistically, PD treatment downregulated the expression levels of antiapoptotic proteins including MCL-1, BCL-2, and BCL-XL, whereas the expression level of proapoptotic protein BAK was upregulated, followed by the cleavage of the DNA repair enzyme PARP. Moreover, PD synergistically enhanced the cytotoxicity of BCL-2 inhibitor venetoclax. In a SUDHL-4-derived xenograft mouse model, the PD administration significantly constrained the tumor growth without obvious side effects. Therefore, our results provide new insights into the role of PD in lymphoma therapy.

Anti-inflammatory effect and metabolic mechanism of BS012, a mixture of Asarum sieboldii, Platycodon grandiflorum, and Cinnamomum cassia extracts, on atopic dermatitis in vivo and in vitro

BackgroundAtopic dermatitis (AD) is a chronic, relapsing skin disease accompanied by itchy and dry skin. AD is caused by complex interactions between innate and adaptive immune response. AD treatment include glucocorticoids and immunosuppressants. However, long-term treatment can have serious side effects. Thus, an effective AD treatment with fewer side effects is required. Natural materials, including herbal medicines, have potential applications. PurposeThis study evaluated the in vivo and in vitro therapeutic effects of BS012, a mixture of Asarum sieboldii, Platycodon grandiflorum, and Cinnamomum cassia extracts, on AD and investigated the underlying metabolic mechanisms. MethodsThe anti-inflammatory effects of BS012 were assessed using a mouse model of AD induced by 1‑chloro-2,4-dinitrobenzene (DNCB) and in tumor necrosis factor-alpha/interferon-gamma (TNF-α/IFN-γ) stimulated normal human epidermal keratinocytes (NHEKs). In DNCB-induced mice, total dermatitis score, histopathological analysis, and immune cell factors were assessed to evaluate the anti-atopic activity. In TNF-α/IFN-γ-stimulated NHEKs, pro-inflammatory cytokines, chemokines, and related signaling pathways were investigated. Serum and intracellular metabolomics were performed to identify the metabolic mechanism underlying the therapeutic effects of BS012 treatment. ResultsIn DNCB-induced mice, BS012 showed potent anti-atopic activity, including reducing AD-like skin lesions and inhibiting the expression of Th2 cytokines and thymic stromal lymphopoietin. In TNF-α/IFN-γ-stimulated keratinocytes, BS012 dose-dependently inhibited the expression of pro-inflammatory cytokines and chemokines by blocking nuclear factor-kappa B and signal transducer and activator of transcription signaling pathways. Serum metabolic profiles of mice revealed significant changes in lipid metabolism related to inflammation in AD. Intracellular metabolome analysis revealed that BS012 treatment affected the metabolism associated with inflammation, skin barrier function, and lipid organization of the stratum corneum. ConclusionBS012 exerts anti-atopic activity by reducing the Th2-specific inflammatory response and improving skin barrier function in AD in vivo and in vitro. These effects are mainly related to the inhibition of inflammation and recovery of metabolic imbalance in lipid organization. BS012, a novel combination with strong activity in suppressing the Th2-immune response, could be a potential alternative for AD treatment. Furthermore, the metabolic mechanism in vivo and in vitro using a metabolomics approach will provide crucial information for the development of natural products for AD treatment.

Ameliorative Effects of Flavonoids from Platycodon grandiflorus Aerial Parts on Alloxan-Induced Pancreatic Islet Damage in Zebrafish

Platycodon grandiflorus (balloon flower), used as a food reserve as well as in traditional herbal medicine, is known for its multiple beneficial effects. In particular, this plant is widely used as a vegetable in Republic of Korea. We examined the ameliorative effects of P. grandiflorus on alloxan-induced pancreatic islet damage in zebrafish. The aerial part treatment led to a significant recovery in pancreatic islet size and glucose uptake. The efficacy of the aerial part was more potent than that of the root. Eight flavonoids (1-8) were isolated from the aerial part. Structures of two new flavone glycosides, designated dorajiside I (1) and II (2), were elucidated to be luteolin 7-O-α-L-rhamno-pyranosyl (1 → 2)-(6-O-acetyl)-β-D-glucopyranoside and apigenin 7-O-α-L-rhamnopyranosyl (1 → 2)-(6-O-acetyl)-β-D-glucopyranoside, respectively, by spectroscopic analysis. Compounds 1, 3, 4 and 6-8 yielded the recovery of injured pancreatic islets in zebrafish. Among them, compound 7 blocked KATP channels in pancreatic β-cells. Furthermore, compounds 3, 4, 6 and 7 showed significant changes with respect to the mRNA expression of GCK, GCKR, GLIS3 and CDKN2B compared to alloxan-induced zebrafish. In conclusion, the aerial part of P. grandiflorus and its constituents conferred a regenerative effect on injured pancreatic islets.

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.

Aqueous extract of Platycodon grandiflorus attenuates lipopolysaccharide-induced apoptosis and inflammatory cell infiltration in mouse lungs by inhibiting PI3K/Akt signaling

BackgroundAcute lung injury (ALI), an acute inflammatory lung disease, can cause a rapid inflammatory response in clinic, which endangers the patient's life. The components of platycodon grandiflorum, such as platycodins have a wide range of pharmacological activities such as expectorant, anti-apoptotic, anti-inflammatory, anti-tumor and anti-oxidant properties, and can be used for improving human immunity. Previous studies have shown that aqueous extract of platycodon grandiflorum (PAE) has a certain protective effect on ALI, but the main pharmacodynamic components and the mechanism of action are not clear.MethodsThe anti-inflammatory properties of PAE were studied using the lipopolysaccharide (LPS)-induced ALI animal model. Hematoxylin and eosin stains were used to assess the degree of acute lung damage. Changes in RNA levels of pro-inflammatory cytokines in the lungs were measured using quantitative RT-qPCR. The potential molecular mechanism of PAE preventing ALI was predicted by lipidomics and network pharmacology. To examine the anti-apoptotic effects of PAE, TdT-mediated dUTP nick-end labelling (TUNEL) was employed to determine apoptosis-related variables. The amounts of critical pathway proteins and apoptosis-related proteins were measured using Western blotting.ResultsTwenty-six chemical components from the PAE were identified, and their related pathways were obtained by the network pharmacology. Combined with the analysis of network pharmacology and literature, it was found that the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) signaling pathway is related to ALI. The results of lipidomics show that PAE alleviates ALI via regulating lung lipids especially phosphatidylinositol (PI). Finally, the methods of molecular biology were used to verify the mechanism of PAE. It can be found that PAE attenuates the inflammatory response to ALI by inhibiting apoptosis through PI3K/Akt signaling pathway.ConclusionThe study revealed that the PAE attenuates lipopolysaccharide-induced apoptosis and inflammatory cell infiltration in mouse lungs by inhibiting PI3K/Akt signaling. Furthermore, our findings provide a novel strategy for the application of PAE as a potential agent for preventing patients with ALI.

Platycodon grandiflorus polysaccharide regulates colonic immunity through mesenteric lymphatic circulation to attenuate ulcerative colitis.

Platycodon grandiflorus polysaccharide (PGP) is one of the main components of P. grandiflorus, but the mechanism of its anti-inflammatory effect has not been fully elucidated. The aim of this study was to evaluate the therapeutic effect of PGP on mice with dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) and explore the underlying mechanisms. The results showed that PGP treatment inhibited the weight loss of DSS-induced UC mice, increased colon length, and reduced DAI, spleen index, and pathological damage within the colon. PGP also reduced the levels of pro-inflammatory cytokines and inhibited the enhancement of oxidative stress and MPO activity. Meanwhile, PGP restored the levels of Th1, Th2, Th17, and Treg cell-related cytokines and transcription factors in the colon to regulate colonic immunity. Further studies revealed that PGP regulated the balance of colonic immune cells through mesenteric lymphatic circulation. Taken together, PGP exerts anti-inflammatory and anti-oxidant effect and regulates colonic immunity to attenuate DSS-induced UC through mesenteric lymphatic circulation.

Chromosome-Scale Genome Assembly and Triterpenoid Saponin Biosynthesis in Korean Bellflower (Platycodon grandiflorum)

Platycodon grandiflorum belongs to the Campanulaceae family and is an important medicinal and food plant in East Asia. However, on the whole, the genome evolution of P. grandiflorum and the molecular basis of its major biochemical pathways are poorly understood. We reported a chromosome-scale genome assembly of P. grandiflorum based on a hybrid method using Oxford Nanopore Technologies, Illumina sequences, and high-throughput chromosome conformation capture (Hi-C) analysis. The assembled genome was finalized as 574 Mb, containing 41,355 protein-coding genes, and the genome completeness was assessed as 97.6% using a Benchmarking Universal Single-Copy Orthologs analysis. The P. grandiflorum genome comprises nine pseudo-chromosomes with 56.9% repeat sequences, and the transcriptome analysis revealed an expansion of the 14 beta-amylin genes related to triterpenoid saponin biosynthesis. Our findings provide an understanding of P. grandiflorum genome evolution and enable genomic-assisted breeding for the mass production of important components such as triterpenoid saponins.

Platycodin D suppresses proliferation, migration, and invasion of human glioblastoma cells through regulation of Skp2

BackgroundPlatycodin D (PD) is a major bioactive component of Platycodon grandiflorum, a medicinal herb that is widely used in China, and is effective against various human cancers, including glioblastoma multiforme (GBM). S phase kinase-related protein 2 (Skp2) is oncogenic and overexpressed in various human tumors. It is highly expressed in GBM and its expression is correlated with tumor growth, drug resistance and poor prognosis. In this study, we investigated whether inhibition of glioma progression by PD is mediated by decreasing expression of Skp2. MethodsCell Counting Kit-8 (CCK-8) and Transwell assays were used to determine the effects of PD on GBM cell proliferation, migration, and invasion in vitro. mRNA and protein expression were determined by real time polymerase chain reaction (RT-PCR) and western blotting, respectively. The U87 xenograft model was used to verify the anti-glioma effect of PD in vivo. Expression levels of Skp2 protein were analyzed by immunofluorescence staining. ResultsPD suppressed proliferation and motility of GBM cells in vitro. The expression of Skp2 in U87 and U251 cells was significantly reduced by PD. PD mainly decreased the cytoplasmic expression of Skp2 in glioma cells. Skp2 protein expression was downregulated by PD, resulting in upregulation of its downstream targets, p21and p27. The inhibitory effect of PD was enhanced by Skp2 knockdown in GBM cells and reversed in cells with Skp2 overexpression. ConclusionPD suppresses glioma development by regulation of Skp2 in GBM cells.

Genome-wide identification and expression profiling analysis of the trihelix gene family and response of PgGT1 under abiotic stresses in Platycodon grandiflorus

The trihelix gene family plays an important role in plant growth and abiotic stress responses. Through the analysis of genomic and transcriptome data, 35 trihelix family members were identified for the first time in Platycodon grandiflorus; they were classified into five subfamilies: GT-1, GT-2, SH4, GTγ, and SIP1. The gene structure, conserved motifs and evolutionary relationships were analyzed. Prediction of physicochemical properties of the 35 trihelix proteins founded, the number of amino acid molecules is between 93 and 960, theoretical isoelectric point is between 4.24 and 9.94, molecular weight is between 9829.77 and 107435.38, 4 proteins among them were stable, and all GRAVY is negative. The full-length cDNA sequence of the PgGT1 gene of the GT-1 subfamily was cloned by PCR. It is a 1165 bp ORF encoding a 387 amino acid protein, with a molecular weight of 43.54 kDa. The predicted subcellular localization of the protein in the nucleus was experimentally verified. After being treated with NaCl, PEG6000, MeJA, ABA, IAA, SA, and ethephon, the expression of PgGT1 gene showed an up-regulated trend except for the roots treated with NaCl and ABA. This study laid a bioinformatics foundation for the research of trihelix gene family and the cultivation of excellent germplasm of P. grandiflorus.

MALDI Imaging Assisted Discovery of a Di-O-glycosyltransferase from Platycodon grandiflorum Root.

A matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) assisted genome mining strategy was developed for the discovery of glycosyltransferase (GT) from the root of Platycodon grandiflorum. A di-O-glycosyltransferase PgGT1 was discovered and characterized that is capable of catalyzing platycoside E (PE) synthesis through the attachment of two β-1,6-linked glucosyl residues sequentially to the glucosyl residue at the C3 position of platycodin D (PD). Although UDP-glucose is the preferred sugar donor for PgGT1, it could also utilize UDP-xylose and UDP-N-acetylglucosamine as weak donors. Residues S273, E274, and H350 played important roles in stabilizing the glucose donor and positioning the glucose in the optimal orientation for the glycosylation reaction. This study clarified two key steps involved in the biosynthetic pathway of PE and could greatly contribute to improving its industrial biotransformation.