The stem and branch extract of Tripterygium wilfordii (Celastraceae) afforded seven new dihydroagarofuran sesquiterpene polyesters [tripterysines A-G (1-7)] and eight known ones (8-15). The chemical structures of these new compounds were established based on combinational analysis of HR-ESI-MS and NMR techniques. The absolute configurations of tripterysines A-C (1-3) and E-G (5-7) were determined by X-ray crystallographic analysis and circular dichroism spectra. All the compounds were screened for their inhibitory effect on inflammation through determining their inhibitory effect on nitric oxide production in LPS-induced RAW 264.7 cells and the secretion of inflammatory cytokines TNF-α and IL-6 in LPS-induced BV2 macrophages. Compound 9 exhibited significant inhibitory activity on NO production with an IC₅₀ value of 8.77 μmol·L^-1. Moreover, compound 7 showed the strongest inhibitory effect with the secretion of IL-6 at 27.36%.
Tripterygium/chemistry* ; Esters/pharmacology* ; Interleukin-6 ; Lipopolysaccharides/pharmacology* ; Plant Leaves/chemistry* ; Anti-Inflammatory Agents/chemistry* ; Nitric Oxide/analysis* ; Sesquiterpenes/chemistry* ; Molecular Structure

The present study aimed to investigate the protective effect of S-propargyl-cysteine (SPRC) on atherosclerosis progression in mice. A mouse model of vulnerable atherosclerotic plaque was created in ApoE^-/- mice by carotid artery tandem stenosis (TS) combined with a Western diet. Macrophotography, lipid profiles, and inflammatory markers were measured to evaluate the antiatherosclerotic effects of SPRC compared to atorvastatin as a control. Histopathological analysis was performed to assess the plaque stability. To explore the protective mechanism of SPRC, human umbilical vein endothelial cells (HUVECs) were cultured in vitro and challenged with oxidized low-density lipoprotein (ox-LDL). Cell viability was determined with a Cell Counting Kit-8 (CCK-8). Endothelial nitric oxide synthase (eNOS) phosphorylation and mRNA expression were detected by Western blot and RT-qPCR respectively. The results showed that the lesion area quantified by en face photographs of the aortic arch and carotid artery was significantly less, plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were reduced, plaque collagen content was increased and matrix metalloproteinase-9 (MMP-9) was decreased in 80 mg/kg per day SPRC-treated mice compared with model mice. These findings support the role of SPRC in plaque stabilization. In vitro studies revealed that 100 μmol/L SPRC increased the cell viability and the phosphorylation level of eNOS after ox-LDL challenge. These results suggest that SPRC delays the progression of atherosclerosis and enhances plaque stability. The protective effect may be at least partially related to the increased phosphorylation of eNOS in endothelial cells.
Animals ; Humans ; Mice ; Atherosclerosis ; Cholesterol/metabolism* ; Cysteine/pharmacology* ; Human Umbilical Vein Endothelial Cells/metabolism* ; Lipoproteins, LDL/pharmacology* ; Nitric Oxide Synthase Type III/metabolism* ; Phosphorylation ; Plaque, Atherosclerotic/pathology*

OBJECTIVES: Endothelium-dependent vasodilation dysfunction is the pathological basis of diabetic macroangiopathy. The utilization and adaptation of endothelial cells to high glucose determine the functional status of endothelial cells. Glycolysis pathway is the major energy source for endothelial cells. Abnormal glycolysis plays an important role in endothelium-dependent vasodilation dysfunction induced by high glucose. Pyruvate kinase isozyme type M2 (PKM2) is one of key enzymes in glycolysis pathway, phosphorylation of PKM2 can reduce the activity of pyruvate kinase and affect the glycolysis process of glucose. TEPP-46 can stabilize PKM2 in its tetramer form, reducing its dimer formation and phosphorylation. Using TEPP-46 as a tool drug to inhibit PKM2 phosphorylation, this study aims to explore the impact and potential mechanism of phosphorylated PKM2 (p-PKM2) on endothelial dependent vasodilation function in high glucose, and to provide a theoretical basis for finding new intervention targets for diabetic macroangiopathy. METHODS: The mice were divided into 3 groups: a wild-type (WT) group (a control group, C57BL/6 mice) and a db/db group (a diabetic group, db/db mice), which were treated with the sodium carboxymethyl cellulose solution (solvent) by gavage once a day, and a TEPP-46 group (a treatment group, db/db mice+TEPP-46), which was gavaged with TEPP-46 (30 mg/kg) and sodium carboxymethyl cellulose solution once a day. After 12 weeks of treatment, the levels of p-PKM2 and PKM2 protein in thoracic aortas, plasma nitric oxide (NO) level and endothelium-dependent vasodilation function of thoracic aortas were detected. High glucose (30 mmol/L) with or without TEPP-46 (10 μmol/L), mannitol incubating human umbilical vein endothelial cells (HUVECs) for 72 hours, respectively. The level of NO in supernatant, the content of NO in cells, and the levels of p-PKM2 and PKM2 protein were detected. Finally, the effect of TEPP-46 on endothelial nitric oxide synthase (eNOS) phosphorylation was detected at the cellular and animal levels. RESULTS: Compared with the control group, the levels of p-PKM2 in thoracic aortas of the diabetic group increased (P<0.05). The responsiveness of thoracic aortas in the diabetic group to acetylcholine (ACh) was 47% lower than that in the control group (P<0.05), and that in TEPP-46 treatment group was 28% higher than that in the diabetic group (P<0.05), while there was no statistically significant difference in the responsiveness of thoracic aortas to sodium nitroprusside (SNP). Compared with the control group, the plasma NO level of mice decreased in the diabetic group, while compared with the diabetic group, the phosphorylation of PKM2 in thoracic aortas decreased and the plasma NO level increased in the TEPP-46 group (both P<0.05). High glucose instead of mannitol induced the increase of PKM2 phosphorylation in HUVECs and reduced the level of NO in supernatant (both P<0.05). HUVECs incubated with TEPP-46 and high glucose reversed the reduction of NO production and secretion induced by high glucose while inhibiting PKM2 phosphorylation (both P<0.05). At the cellular and animal levels, TEPP-46 reversed the decrease of eNOS (ser1177) phosphorylation induced by high glucose (both P<0.05). CONCLUSIONS p-PKM2 may be involved in the process of endothelium-dependent vasodilation dysfunction in Type 2 diabetes by inhibiting p-eNOS (ser1177)/NO pathway.
Animals ; Humans ; Mice ; Carboxymethylcellulose Sodium/pharmacology* ; Diabetes Mellitus, Type 2/metabolism* ; Endothelium, Vascular/metabolism* ; Glucose/metabolism* ; Human Umbilical Vein Endothelial Cells ; Mice, Inbred C57BL ; Nitric Oxide/metabolism* ; Nitric Oxide Synthase Type III/metabolism* ; Phosphorylation ; Pyruvate Kinase/metabolism* ; Vasodilation

OBJECTIVE: To investigate the anti-oxidant and anti-inflammatory effects of ethanol extract of Polygala sibirica L. var megalopha Fr. (EEP) on RAW264.7 mouse macrophages. METHODS: RAW264.7 cells were pretreated with 0-200 µg/mL EEP or vehicle for 2 h prior to exposure to 1 µg/mL lipopolysaccharide (LPS) for 24 h. Nitric oxide (NO) and prostaglandin (PGE₂) production were determined by Griess reagent and enzyme-linked immunosorbent assay (ELISA), respectively. The mRNA levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor α (TNF-α), interleukin-1beta (IL-1β), and IL-6 were determined using reverse transcription polymerase chain reaction (RT-PCR). Western blot assay was used to determine the protein expressions of iNOS, COX-2, phosphorylation of extracellular regulated protein kinases (ERK1/2), c-Jun N-terminal kinase (JNK), inhibitory subunit of nuclear factor Kappa B alpha (Iκ B-α) and p38. Immunofluorescence was used to observe the nuclear expression of nuclear factor-κ B p65 (NF-κ B p65). Additionally, the anti-oxidant potential of EEP was evaluated by reactive oxygen species (ROS) production and the activities of catalase (CAT) and superoxide dismutase (SOD). The 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl (OH), superoxide anion (O₂^-) radical and nitrite scavenging activity were also measured. RESULTS: The total polyphenol and flavonoid contents of EEP were 23.50±2.16 mg gallic acid equivalent/100 g and 43.78±3.81 mg rutin equivalent/100 g. With EEP treatment (100 and 150 µg/mL), there was a notable decrease in NO and PGE₂ production induced by LPS in RAW264.7 cells by downregulation of iNOS and COX-2 mRNA and protein expressions (P<0.01 or P<0.05). Furthermore, with EEP treatment (150 µg/mL), there was a decrease in the mRNA expression levels of TNF-α, IL-1β and IL-6, as well as in the phosphorylation of ERK, JNK and p38 mitogen-activated protein kinase (MAPK, P<0.01 or P<0.05), by blocking the nuclear translocation of NF-κ B p65 in LPS-stimulated cells. In addition, EEP (100 and 150 µg/mL) led to an increase in the anti-oxidant enzymes activity of SOD and CAT, with a concomitant decrease in ROS production (P<0.01 or P<0.05). EEP also indicated the DPPH, OH, O₂^- radical and nitrite scavenging activity. CONCLUSION EEP inhibited inflammatory responses in activated macrophages through blocking MAPK/NF-κ B pathway and protected against oxidative stress.
Animals ; Mice ; Antioxidants/pharmacology* ; Lipopolysaccharides/pharmacology* ; Polygala ; Transcription Factor RelA/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Ethanol/chemistry* ; Interleukin-6/metabolism* ; Anti-Inflammatory Agents/chemistry* ; Reactive Oxygen Species/metabolism* ; Cyclooxygenase 2/metabolism* ; Nitrites/metabolism* ; NF-kappa B/metabolism* ; Nitric Oxide/metabolism* ; Superoxide Dismutase/metabolism* ; RNA, Messenger ; Nitric Oxide Synthase Type II/metabolism*

We reported the discovery of six novel coumarins, toddasirins A-F (1-6), each endowed with modified isoprenyl or geranyl side chains, derived from the roots of Toddalia asiatica. Comprehensive structural elucidation was achieved through multispectroscopic analyses, single-crystal X-ray diffraction experiments, and advanced quantum mechanical electronic circular dichroism (ECD) calculations. Furthermore, the anti-inflammatory activity of these compounds was assessed. Notably, compounds 1-3 and 6 demonstrated notable inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells, with 50% inhibitory concentration (IC₅₀) values of 3.22, 4.78, 8.90, and 4.31 μmol·L^-1, respectively.
Mice ; Animals ; Coumarins/chemistry* ; Rutaceae/chemistry* ; Anti-Inflammatory Agents/pharmacology* ; Plant Extracts/chemistry* ; RAW 264.7 Cells ; Nitric Oxide ; Molecular Structure

Natural products are essential sources of antitumor drugs. One such molecule, β-elemene, is a potent antitumor compound extracted from Curcuma wenyujin. In the present investigation, a series of novel 13,14-disubstituted nitric oxide (NO)-donor β-elemene derivatives were designed, with β-elemene as the foundational compound, and subsequently synthesized to evaluate their therapeutic potential against leukemia. Notably, the derivative labeled as compound 13d demonstrated a potent anti-proliferative activity against the K562 cell line, with a high NO release. In vivo studies indicated that compound 13d could effectively inhibit tumor growth, exhibiting no discernible toxic manifestations. Specifically, a significant tumor growth inhibition rate of 62.9% was observed in the K562 xenograft tumor mouse model. The accumulated data propound the potential therapeutic application of compound 13d in the management of leukemia.
Humans ; Mice ; Animals ; Cell Line, Tumor ; Nitric Oxide Donors/pharmacology* ; Sesquiterpenes/pharmacology* ; Leukemia/drug therapy* ; Biological Assay ; Cell Proliferation

OBJECTIVE: To investigate the influence of electroacupuncture (EA) on ghrelin and the phosphoinositide 3-kinase/protein kinase B/endothelial nitric oxide synthase (PI3K/Akt/eNOS) signaling pathway in spontaneously hypertensive rats (SHRs). METHODS: Eight Wistar-Kyoto rats were used as the healthy blood pressure (BP) control (normal group), and 32 SHRs were randomized into model group, EA group, EA plus ghrelin group (EA + G group), and EA plus PF04628935 group (a potent ghrelin receptor blocker; EA + P group) using a random number table. Rats in the normal group and model group did not receive treatment, but were immobilized for 20 min per day, 5 times a week, for 4 continuous weeks. SHRs in the EA group, EA + G group and EA + P group were immobilized and given EA treatment in 20 min sessions, 5 times per week, for 4 weeks. Additionally, 1 h before EA, SHRs in the EA + G group and EA + P group were intraperitoneally injected with ghrelin or PF04628935, respectively, for 4 weeks. The tail-cuff method was used to measure BP. After the 4-week intervention, the rats were sacrificed by cervical dislocation, and pathological morphology of the abdominal aorta was observed using hematoxylin-eosin (HE) staining. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of ghrelin, nitric oxide (NO), endothelin-1 (ET-1) and thromboxane A2 (TXA2) in the serum. Isolated thoracic aortic ring experiment was performed to evaluate vasorelaxation. Western blot was used to measure the expression of PI3K, Akt, phosphorylated Akt (p-Akt) and eNOS proteins in the abdominal aorta. Further, quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to measure the relative levels of mRNA expression for PI3K, Akt and eNOS in the abdominal aorta. RESULTS: EA significantly reduced the systolic BP (SBP) and diastolic BP (DBP) (P < 0.05). HE staining showed that EA improved the morphology of the vascular endothelium to some extent. Results of ELISA indicated that higher concentrations of ghrelin and NO, and lower concentrations of ET-1 and TXA2 were presented in the EA group (P < 0.05). The isolated thoracic aortic ring experiment demonstrated that the vasodilation capacity of the thoracic aorta increased in the EA group. Results of Western blot and qRT-PCR showed that EA increased the abundance of PI3K, p-Akt/Akt and eNOS proteins, as well as expression levels of PI3K, Akt and eNOS mRNAs (P < 0.05). In the EA + G group, SBP and DBP decreased (P < 0.05), ghrelin concentrations increased (P < 0.05), and the concentrations of ET-1 and TXA2 decreased (P < 0.05), relative to the EA group. In addition, the levels of PI3K and eNOS proteins, the p-Akt/Akt ratio, and the expression of PI3K, Akt and eNOS mRNAs increased significantly in the EA + G group (P < 0.05), while PF04628935 reversed these effects. CONCLUSION EA effectively reduced BP and protected the vascular endothelium, and these effects may be linked to promoting the release of ghrelin and activation of the PI3K/Akt/eNOS signaling pathway.
Animals ; Electroacupuncture ; Ghrelin/pharmacology* ; Nitric Oxide/metabolism* ; Nitric Oxide Synthase Type III/pharmacology* ; Phosphatidylinositol 3-Kinase/pharmacology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/pharmacology* ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY ; Signal Transduction

OBJECTIVE: To investigate the effect of biflavonoid 4'-O-methylochnaflavone (MF) on palmitic acid-induced endothelial dysfunction in rat cavernous endothelial cells (RCECs). METHODS: The isolated RCECs were commercially available and randomly divided into four groups: normal+BSA group (NC group), palmitic acid (PA) group, MF group, and icariside Ⅱ (ICA Ⅱ) group. The protein expression levels of protein kinase B (PKB/AKT) and endothelial nitric oxide synthase (eNOS) in each group were evaluated via Western blotting. The differences in the intracellular nitric oxide of RCECs treated by MF or ICA Ⅱ were detected by DAF-FM DA that served as a nitric oxide fluorescent probe. Effects of MF and ICA Ⅱ on cell proliferation of PA-stimulated RCECs were determined via CCK-8 assay. RESULTS: The content of nitric oxide in RCECs was significantly increased after the treatment of MF and ICA Ⅱ in comparison with the NC group (P < 0.05). Moreover, compared with ICA Ⅱ group, MF demonstrated a more obvious effect in promoting nitric oxide production (P < 0.05). Compared with the NC group, the expression levels of eNOS and AKT in the PA group were significantly decreased, indicating that a model for simulating the high-fat environment in vitro was successfully constructed (P < 0.05). Meanwhile, the intervention of MF and ICA Ⅱ could effectively increase the expression of eNOS and AKT, suggesting that MF and ICA Ⅱ could promote the recovery of endothelial dysfunction caused by high levels of free fatty acids (P < 0.05). The results of CCK-8 assays showed that PA could significantly reduce the proli-feration ability of RCECs (P < 0.05). Furthermore, the decreased cell viability induced by PA was significantly elevated by treatment with ICA Ⅱ and MF (P < 0.05). CONCLUSION In RCECs, MF and ICA Ⅱ could effectively increase the content of nitric oxide. The down-regulation of the expression of proteins associated with the AKT/eNOS pathway after PA treatment revealed that this pathway was involved in the development of endothelial dysfunction, which could be effectively reversed by MF and ICA Ⅱ. In addition, the cell proliferation ability was significantly decreased following PA treatment, but MF and ICA Ⅱ could restore the above changes. Overall, biflavonoid MF has an obvious repairing effect on PA-stimulated endothelial dysfunction.
Animals ; Biflavonoids/pharmacology* ; Cells, Cultured ; Endothelial Cells/metabolism* ; Nitric Oxide/pharmacology* ; Nitric Oxide Synthase Type III/pharmacology* ; Palmitic Acid/pharmacology* ; Phosphorylation ; Proto-Oncogene Proteins c-akt/metabolism* ; Rats ; Signal Transduction ; Sincalide/pharmacology*

Cadmium (Cd) is a common heavy metal in the environment. Cd²⁺ may penetrate the blood-brain barrier and produce neurotoxicity, thus inducing various neurodegenerative diseases. Celastrol is an effective component of Tripterygium wilfordii Hook. F., which has many pharmacological effects such as anti-cancer and anti-inflammatory. Here we explored the effect of celastrol on the corresponding neurotoxicity induced by Cd²⁺. Cell proliferation test, cell membrane integrity test, and cell morphology were observed to analyze the effect of Cd²⁺ on the viability of HMC3. The neurotoxicity of Cd²⁺ and the effect of celastrol on the corresponding neurotoxicity induced by Cd²⁺ were analyzed by nitric oxide (NO) test, lipid peroxidation (MDA) test, and Western blotting. When the concentration of Cd²⁺ reached 40 μmol/L, the inhibition rate of HMC3 cell proliferation was (57.17±8.23)% (P < 0.01, n=5), compared with the control group. The cell activity continued to reduce when the Cd²⁺ concentration further increased. When the concentration of Cd²⁺ was higher than 40 μmol/L, the cell membrane of HMC3 was significantly damaged, and the damage was dose-dependent. Upon increasing the Cd²⁺ concentration, the cell morphology began to change and the adhesion also became worse. Cd²⁺ significantly increased the amount of NO released by HMC3 cells, while celastrol effectively inhibited the NO release of HMC3 cells induced by Cd²⁺. Cd²⁺ greatly increased the release of MDA in HMC3 cells, and the level of MDA decreased rapidly upon the addition of 10^-7 mol/L celastrol. Cd²⁺ increased the expression of p-PI3K protein, and the levels of p-PI3K protein and p-AKT protein were inhibited by the addition of celastrol (10^‒7 mol/L, 10^‒6 mol/L), thus preventing cell apoptosis. In conclusion, celastrol inhibits Cd²⁺ induced microglial cytotoxicity and plays a neuroprotective role.
Anti-Inflammatory Agents/pharmacology* ; Apoptosis ; Cadmium/toxicity* ; Nitric Oxide/pharmacology* ; Pentacyclic Triterpenes ; Phosphatidylinositol 3-Kinases ; Proto-Oncogene Proteins c-akt/metabolism* ; Triterpenes/pharmacology*

Carthamus tinctorius is proved potent in treating ischemic stroke. Flavonoids, such as safflower yellow, hydroxysafflor yellow A(HSYA), nicotiflorin, safflower yellow B, and kaempferol-3-O-rutinoside, are the main substance basis of C. tinctorius in the treatment of ischemic stroke, and HSYA is the research hotspot. Current studies have shown that C. tinctorius can prevent and treat ischemic stroke by reducing inflammation, oxidative stress, and endoplasmic reticulum stress, inhibiting neuronal apoptosis and platelet aggregation, as well as increasing blood flow. C. tinctorius can regulate the pathways including nuclear factor(NF)-κB, mitogen-activated protein kinase(MAPK), signal transducer and activator of transcription protein 3(STAT3), and NF-κB/NLR family pyrin domain containing 3(NLRP3), and inhibit the activation of cyclooxygenase-2(COX-2)/prostaglandin D2/D prostanoid receptor pathway to alleviate the inflammatory development during ischemic stroke. Additionally, C. tinctorius can relieve oxidative stress injury by inhibiting oxidation and nitrification, regulating free radicals, and mediating nitric oxide(NO)/inducible nitric oxide synthase(iNOS) signals. Furthermore, mediating the activation of Janus kinase 2(JAK2)/STAT3/suppressor of cytokine signaling 3(SOCS3) signaling pathway and phosphoinositide 3-kinase(PI3 K)/protein kinase B(Akt)/glycogen synthase kinase-3β(GSK3β) signaling pathway and regulating the release of matrix metalloproteinase(MMP) inhibitor/MMP are main ways that C. tinctorius inhibits neuronal apoptosis. In addition, C. tinctorius exerts the therapeutic effect on ischemic stroke by regulating autophagy and endoplasmic reticulum stress. The present study reviewed the molecular mechanisms of C. tinctorius in the treatment of ischemic stroke to provide references for the clinical application of C. tinctorius.
Carthamus tinctorius/chemistry* ; Chalcone/therapeutic use* ; Cyclooxygenase 2/metabolism* ; Cytokines/metabolism* ; Flavonoids/therapeutic use* ; Glycogen Synthase Kinase 3 beta/metabolism* ; Humans ; Ischemic Stroke/drug therapy* ; Janus Kinase 2/metabolism* ; Mitogen-Activated Protein Kinases/metabolism* ; NF-kappa B/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Nitric Oxide/metabolism* ; Nitric Oxide Synthase Type II/metabolism* ; Phosphatidylinositol 3-Kinase/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Prostaglandin D2 ; Proto-Oncogene Proteins c-akt/metabolism* ; Quinones/pharmacology*