Tetrandrine Represses Inflammation and Attenuates Osteoarthritis by Selective Inhibition of COX-2

Objective There is a lack of effective and long-term safe drugs for the treatment of osteoarthritis(OA).Tetrandrine(Tet)has been approved and used to treat rheumatoid arthritis for several decades,but its effect on OA has not been investigated.Herein,we explored the effect of Tet on OA and its underlying mechanism.Methods OA was induced using destabilization of the medial meniscus(DMM)in C57BL/6J mice.The animals were randomly divided into sham,DMM,Tet,celecoxib(CXB),and indomethacin(INDO)groups.Each group was given solvent or corresponding drugs by gavage for 7 weeks after convalescence.Pathological staining,OARSI scores,micro-computed tomography and behavior tests were performed to evaluate the effects of Tet.Results Tet remarkably alleviated cartilage injury in the knee joint,limited bone remodeling in the subchondral bone,and delayed progression of OA.Tet also significantly relieved joint pain and maintained function.Further mechanistic studies revealed that Tet lowered inflammatory cytokine levels and selectively suppressed gene and protein expression of cyclooxygenase(COX)-2 but not COX-1(P<0.01).Tet also reduced the production of prostaglandin E2 without damaging the gastric mucosa.Conclusion We found that Tet could selectively inhibit COX-2 gene expression and decrease cytokine levels in mice,thus reducing inflammation and improving OA without obvious gastric adverse events.These results provide a scientific basis for the clinical application of Tet in the treatment of OA.

Progress in studies of tetrandrine against hepatofibrosis

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The Effects of Tetrandrine (TT) and Polyvinylpyridine-N-Oxide (PVNO) on Gene Expression of Type Ⅰand Type ⅢCollagens during Experimental Silicosis

In the screening tests of drugs for silicosis in our laboratory, we found that TT, a type of alkaloid isolated from Stephania tetrandra, could inhibit the development of experimental silicosis of rats and the synthesis of collagen in rat lung. Chest X-rays of silicotic patients treaied with TT for 1-3 years showed obvious changes. The silicotic nodules became smallel and shadows became clearer. PVNO was proved to have anti-silicotic effect on animal and clinically. This presentation reports the effect of them on collagen mRNA.Dot blot results showed that 1 (Ⅰ) and 1 (Ⅲ) mRNA levels increased significantly at 60 and 120 days after the rats were exposed to silica dust. The mRNA levels went down at 1 and 3 months after treated by TT and PVNO. In situ hybridization observation revealed that the silver grains of Type Ⅰand Type Ⅲ collagen were scattered within the fibroblasts in cellular nodules and in thickened interstitium of silicosis tissue. The amounts of mRNA silver grains decreased in the lung tissue treated by TT and PVNO. It was suggested that TT and PVNO may inhibil the gene expression of collagen during silicosis

Pharmacology of tetrandrine and its therapeutic use in digestive diseases

INTRODUCTIONTetrandrine (Tet) is a dibenzylisoquinoline alkaloid isolatedfrom Stephania tetrandra S. Moore, a Chinese herbalmedicine. In the past decade, lots of studies demonstrated that Tet has multiple bioactivities, It is promising to use Tet as an antifibrogenetic in liver or lung fibrosis with or without portal or pulmonary hypertension, as well as an immunomodulating and anticarcinoma drug.

Tetrandrine:A Potent Abrogator of G_2 Checkpoint Function in Tumor Cells and Its Mechanism

Objective To assess the ability of tetrandrine （Tet） to enhance the sensitivity to irradiation and its mechanism in cell lines of human breast cancer p53-mutant MCF-7/ADR, p53-wild-type MCF-7 and human colon carcinoma p53-mutant HT-29 as well as in C26 colorectal carcinoma-bearing BALB/c mice. Methods MCF-7/ADR, HT-29 and MCF-7 cells were exposed to irradiation in the absence or presence of tetrandrine. The effect of Tet on the cytotoxicity of X-irradiation in these three cells was determined and the effect of tetrandrine on cell cycle arrest induced by irradiation in its absence or presence was studied by flow cytometry. Moreover, mitotic index measurement determined mitosis of cells to enter mitosis. Western blotting was employed to detect cyclin B1 and Cdc2 proteins in extracts from irradiated or non-irradiated cells of MCF-7/ADR, HT-29 and MCF-7 treated with tetrandrine at various concentrations. Tumor growth delay assay was conducted to determine the radio-sensitization of tetrandrine in vivo. Results Clonogenic assay showed that tetrandrine markedly enhanced the lethal effect of X-rays on p53-mutant MCF-7/ADR and HT-29 cells and the sensitization enhancement ratio （SER） of tetrandrine was 1.51 and 1.63, but its SER was only 1.1 in p53-wt MCF-7 cells. Irradiated p53-mutant MCF-7/ADR and HT-29 cells were only arrested in G2/M phase while MCF-7 cells were arrested in G1 and G2/M phases. Radiation-induced G2 phase arrests were abrogated by tetrandrine in a concentration-dependent manner in MCF-7/ADR and HT-29 cells, whereas redistribution within MCF-7 cell cycle changed slightly. The proportion of cells in M phase increased from 1.3% to 14.7% in MCF-7/ADR cells, and from 1.5% to 13.2% in HT-29 cells, but 2.4% to 7.1% in MCF-7 cells. Furthermore, the levels of cyclin B 1 and Cdc2 expression decreased after X-irradiation in MCF-7/ADR and HT-29 cells, and the mitotic index was also lower. Tet could reverse the decrease and induce the irradiated cells to enter mitosis （M phase）. Endosomatic experiment showed that tetrandrine caused tumor growth delay in irradiated mice. Conclusion Tetrandrine boosts the cell killing activity of irradiation both in vitro and in vivo. Tetrandrine is a potent abrogator for G2 checkpoint control and can sensitize the cells to radiation.

Neuroprotective effects of tetrandrine against vascular dementia

Tetrandrine is one of the major active ingredients in Menispermaceae Stephania tetrandra S.Moore,and has specific therapeutic effects in ischemic cerebrovascular disease.Its use in vascular dementia has not been studied fully.Here,we investigated whether tetrandrine would improve behavioral and cellular impairments in a two-vessel occlusion rat model of chronic vascular dementia.Eight weeks after model establishment,rats were injected intraperitoneally with 10 or 30 mg/kg tetrandrine every other day for 4 weeks.Behavioral assessment in the Morris water maze showed that model rats had longer escape latencies in training trials,and spent less time swimming in the target quadrant in probe trials,than sham-operated rats.However,rats that had received tetrandrine showed shorter escape latencies and longer target quadrant swimming time than untreated model rats.Hematoxylin-eosin and Nissl staining revealed less neuronal necrosis and pathological damage,and more living cells,in the hippocampus of rats treated with tetrandrine than in untreated model rats.Western blot assay showed that interleukin-1β expression,and phosphorylation of the N-methyl-D-aspartate 2B receptor at tyrosine 1472,were lower in model rats that received tetrandrine than in those that did not.The present findings suggest that tetrandrine may be neuroprotective in chronic vascular dementia by reducing interleukin-1β expression,N-methyl-D-aspartate receptor 2B phosphorylation at tyrosine 1472,and neuronal necrosis.

Effects of tetrandrine on gastric mucosa and liver in portal hypertensive rats

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Multilayer Coating of Tetrandrine-loaded PLGA Nanoparticles: Effect of Surface Charges on Cellular Uptake Rate and Drug Release Profile

The effect of surface charges on the cellular uptake rate and drug release profile of tetrandrine-loaded poly（lactic-co-glycolic acid）（PLGA） nanoparticles（TPNs） was studied. Stabilizer-free nanoprecipitation method was used in this study for the synthesis of TPNs. A typical layer-by-layer approach was applied for multi-coating particles＇ surface with use of poly（styrene sulfonate） sodium salt（PSS） as anionic layer and poly（allylamine hydrochloride）（PAH） as cationic layer. The modified TPNs were characterized by different physicochemical techniques such as Zeta sizer, scanning electron microscopy and transmission electron microscopy. The drug loading efficiency, release profile and cellular uptake rate were evaluated by high performance liquid chromatography and confocal laser scanning microscopy, respectively. The resultant PSS/PAH/PSS/PAH/TPNs（4 layers） exhibited spherical-shaped morphology with the average size of 160.3±5.165 nm and zeta potential of –57.8 m V. The encapsulation efficiency and drug loading efficiency were 57.88% and 1.73%, respectively. Multi-layer coating of polymeric materials with different charges on particles＇ surface could dramatically influence the drug release profile of TPNs（4 layers vs. 3 layers）. In addition, variable layers of surface coating could also greatly affect the cellular uptake rate of TPNs in A549 cells within 8 h. Overall, by coating particles＇ surface with those different charged polymers, precise control of drug release as well as cellular uptake rate can be achieved simultaneously. Thus, this approach provides a new strategy for controllable drug delivery.

Effects of tetrandrine on the changes of free calcium level in neutrophils after smoke inhalation injury in the rabbit

The changes of the cytoplasmic free calcium level in the neutrophils after smoke in-halation injury were observed in rabbits and then the effects of tetrandrine,a calcium antago-nist,on the changes of free calcium level were studied.It was found that the number of neu-trophils increased significantly preceded by a transient decrease in the blood and also increasedin the bronehoalveolar lavage fluid after smoke inhalation.and the level of cytoplasmic free calci-um in the blood neutrophil increased likewise.Administration of tetrandrine resulted in a reduc-tion of the neutrophils number in the lungs and the free calcium level in the blood neutrophils toalleviate the pulmonary injury due to smoke inhalation.It is believed that there is a close rela-tionship between the activation of neutrophils and the pathophysiological changes of the lungs,and tetrandrine can exert its therapeutic effects on the injury by decreasing the free calcium levelin the neutrophils to modulate their functions.

Tetrandrine Ameliorates Cirrhosis and Portal Hypertension by Inhibiting Nitric Oxide in Cirrhotic Rats

To examine the role and effect of nitric oxide synthase type Ⅱ(NOSⅡ) in cirrhotic rats, expression of NOSⅡ mRNA was detected by real time RT-PCR. The enzymatic activity of nitric oxide synthase and the circulating levels of NO, systemic and portal hemodynamics and quantification of cirrhosis were measured. Chinese traditional medicine was used to treat cirrhotic rats and the effect of NO was evaluated. Double-blind method was used in experiment. Our results showed the concentration of NO and the enzymatic activity of NOS increased markedly at all stages of cirrhosis and iNOSmRNA was strongly expressed. Meanwhile, the portal-venous-pressure (PVP) and portal-venous-flow (PVF) were significantly increased. NO, NOS and iNOSmRNA were positively correlated to the degree of hepatic fibrosis. Tetrandrine significantly inhibited NO production and the expression of iNOSmRNA. Our results suggested that increased hepatic expression of NOSⅡ is one of the important factors causing cirrhosis and portal hypertension. Tetrandrine can significantly ameliorate cirrhosis and portal hypertension.

Effects of tetrandrine on experimental pleurisy in rats

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Exploring the key pathways of tetrandrine in the treatment of early silicosis based on bioinformatics and in vitro experiments

Objective:Exploring the key pathways affecting the development of early silicosis based on bioinformatics and in vitro experiments.Method:Collecting differentially expressed genes in silicosis patients through literature mining;Collecting differentially expressed genes in silicon dioxide infusion mice by using a high-throughput gene expression database(GEO);Obtaining disease targets related to silicosis by means of online human Mendelian genetic database(OMIM),GeneCards and comparative toxicgenomics database(CTD);differentially expressed genes and disease targets were subjected to gene ontology(GO)enrichment analysis and Kyoto Encyclopedia of Genes and Genome(KEGG)enrichment analysis via R-package and Metascape platforms,respectively.The Schrödinger and Pymol software were used for molecular docking and modification.Silicon dioxide-stimulated macrophages and epithelial cells were modeled and analyzed by PCR and western blot(WB).Result:2065 differentially expressed genes in silicosis patients,2291 differentially expressed genes in rat infused with silicon dioxide,and 803 targets for silicosis-related diseases were screened out.GO enrichment analysis mainly involves G protein-coupled receptor binding,the regulation of inflammatory response,and participation in immune response.The enrichment analysis of KEGG pathway mainly included ECM-receptor interaction,TNF signaling pathway,and IL-17 signaling pathway.IL-17 signaling pathway was screened out from different genes and disease targets,indicating that IL-17 signaling pathway might be the key pathway for the development of silicosis.Molecular docking results showed that the silicosis drug tetrandrine had good binding effect with the RAF/MEK/ERK pathway in the IL-17 signaling pathway.Cellular experiments showed that tetrandrine reduced the expression of inflammatory factors such as IL-6 and TGF-βin macrophages by regulating the RAF/MEK/ERKpathway,and inhibited the epithelialmesenchymal transition and expression of inflammatory factors in epithelial cells.Conclusion:Tetrandrine regulates the inflammatory response and epithelial-mesenchymal transition(EMT)through the RAF/MEK/ERK pathway and thus affects the early progression of silicosis.

Effects of tetrandrine on phenotypic modulation of vascular smooth muscle cells and expression of p38 MAPK as well as MKP-1 after intimal injury of rabbit carotid arteries

Objective： To study the effects of tetrandrine （Tet） on phenotypic modulation of vascular smooth muscle cells （VSMCs） and expression of p38 mitogen-activated protein kinase （p38MAPK） as well as mitogen-activated protein kinase phosphatase-1 （MKP-1） after vascular intimal injury. Methods： HE staining was used to analyze vascular morphology of sham-injured group, injured group and Tet-treated group at day 28. lmmunohistochemistry, Western blot and RT-PCR were respectively used to detect the expression change of smooth muscle a-actin （SMa-actin）, proliferation cell nuclear antigen （PCNA）, p38MAPK and MKP-1 of injured group and Tet group at days 7, 14 and 28 after balloon injury. Results： ① All layers of vascular wall in sham-injured group were intact at day 28. The neointimal area was significantly increased and the lumen area notably decreased in injured group at day 28. The neointimal proliferation in Tet treated group was less than that in injured group, and the lumen area of Tet group was significantly increased than that of injured group at day 28. ②Compared with the injured group, the expression of SMa-actin, PCNA, p38MAPK and MKP-1 of vascular wall in Tet group was no difference, and the neointimal proliferation condition was also basically as same as injured group at day 7 after injury. The expression of PCNA and p38MAKP in Tet group was obviously lower than that in injured group, and the expression of MKP-1 in Tet group was obviously higher than that in injured group at days 14 and 28 after injury. The expression of SMa-actin in Tet group was slightly higher than that in injured group at days 14 and 28 after injury. Conclusions： Tet could reduce neointimal proliferation by inhibiting VSMCs phenotypic modulation and p38MAPK signaling transduction pathway as well as its down regulation.

Changes of Apoptosis in Rats of Acute Ischemic Renal Injury under Treatment of Tetrandrine

ObjectiveTo elucidate the effect of tetrandrine on acute ischemic renal injury and its relation with apoptosis. MethodsA model for bilateral post ischemic renal injury in rats was developed by clamping renal pedicles for 45 min. Renal tissular DNA fragmentation analysis and renal tissular HE staining were used. Also quantitative analysis of apoptosis in injured renal tubular epithelium was carried out by using TdT mediated dUTP nick and labeling (TUNEL). ResultsApoptosis of renal tubular epithelium increased in acute ischemic renal injury. Tetrandrine could remarkably decrease the level of apoptosis in injured renal tubule while protecting renal tissue against the ischemic injuries. ConclusionTetrandrine could adjust the level of apoptosis in renal tubular epithelium and alleviate renal tissular injury.

Inhibitory Actions of Tetrandrine on Tumor Necrosis Factor α-Induced NF-κB Activation in Neovascularization of Cultured Choroidal Explants

Tetrandrine (1 μM), a bis-benzylisoquinoline alkaloid isolated from Stephania tetrandra S Moore, signifi-cantly decreased tumor necrosis factor alpha (TNFα;10 ng/ml)-induced increase in the number of micro vessels that budded from cultured rat choroidal explants. Tetrandrine also decreased the TNFα-induced in-crease in the number of cells composing the microvessels. Ammonium pyrrolidine dithiocarbamate (APDC;0.1-0.3 μM), an inhibitor of nuclear factor-κB (NF-κB), decreased the TNFα-induced increase in the number of microvessels in a concentration-dependent manner. TNFα increased the phosphorylation and degradation of inhibitor of NF-κB (IκBα), as well as increasing the DNA-binding activity of NF-κB in choroidal explants. TNF? induced an increase of vascular endothelial growth factor (VEGF)-A mRNA, but not VEGF-C mRNA or VEGF-D mRNA. TNFα-induced angiogenic action was inhibited by treatment of VEGF-A antibody in cultured choroidal capillaries. Tetrandrine inhibited the TNFα-induced increases of phosphorylation and degradation of IκBα, and reduced the TNFα-induced increase of DNA-binding activity of NF-κB in chor-oidal explants. In conclusion, tetrandrine inhibits TNFα-induced activation of NF-κB in the choroidal capil-laries via inhibition of TNFα-induced phosphorylation of IκBα.

Effects of Tetrandrine and Fructose-1,6-diphosphate on the anti-anoxia in mice and in-tracellular free Ca^(2+) level of synaptosomes in rat brain

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Quantitative Proteomic Analysis of Bromotetrandrine and Tetrandrine in K562 Cell Line Using ^(18)O-labeling Method

Objective To compare quantitative proteomic analysis of bromotetrandrine (W198) which was a Class I new antitumor drug in China and tetrandrine (Tet) in K562 cell line using 18O-labeling method. Methods To illustrate its mechanism, a shotgun quantitative proteomic strategy employing 2D LC-MS-MS and trypsin catalyzed 18O-labeling quantification was carried out in this study. Compared to normal chronic leukemia cell line K562 and K562 induced by Tet, the proteomic changes of K562 induced by W198 were investigated. In order to validate the quantitation by the 18O-labeling, the analysis was done on an equivalent sample composed of the same amount of labeled and unlabeled proteins from normally cultured cells to act as a reference to the comparative sample. Results A threshold of ± 2-fold change for deciding whether a protein concentration was changed was settled for the following experiments. Comparing the 105 identified soluble proteins’ expression levels of the apoptosis starting up K562 cells after W198 induction with the normally cultured cells, 16 proteins were found with significantly altered expression levels after W198 treatment. Eight proteins were up-expressed including HMGB2, peroxiredoxin-2, and eIF4A-I, etc. Eight proteins were down-expressed including TCP-1, GRP94, GST-π, and SFGHs, etc. Compared to K562 induced by Tet, eight proteins of K562 were found with significantly altered expression levels after W198 treatment. Five proteins were up-expressed including HSP 90-β and 40S ribosomal protein S15a, etc. Three proteins were down-expressed including phosphoglycerate kinase 1, isoform 5 of interleukin enhancer-binding factor 3, etc. Conclusion The 18O-labeling MS-MS-based method is ideal as a discovery tool, but it is not suitable for validation using a large number of samples. Other more effective methods, such as Western blotting should be used for further validation of candidate cancer proteins discovered from 18O-labeling samples. In total, 105 soluble proteins were discovered, and 16 proteins were found with significantly altered expression levels after W198 treatment. These repressed or activated proteins are the potential drug targets of W198, which may provide novel targets for future development of biomarkers for cancer therapy.

Effect of prenatal tetrandrine therapy on pulmonary vascular structural remodeling in the nitrofen-induced CDH rat model

To examine the effects of prenatal tetrandrine (Tet) therapy on pulmonary arterial structural remodeling in nitrofen-induced congenital diaphragmatic hernia (CDH) Methods CDH was induced in fetal rats by maternal administration of 100*!mg nitrofen by gavage on day 9 5 of gestation (term, day 22) Control animals received olive oil (OO) Tet (24*!mg/kg per day) or normal saline (NS) was given by gavage every day from 16 to 20 days of gestation, and fetuses were delivered by caesarean section on day 21 5 Lung sections from 3 fetuses in each group were studied The number of vessels were calculated, the external diameter (ED), medial wall thickness (MT), percent of medial wall thickness, and wall structure were evaluated by image analysis software Results In the pre-acinar arteries, CDH-NS pups had a significantly increased %MT compared with the OO-NS group ( P <0 05), while CDH-Tet animals had a reduced %MT compared with the CDH-NS rats ( P <0 05) Similar results were seen in the intra-acinar level Significant differences were observed between CDH-NS animals and OO-NS controls in the percentage of muscularized intra-acinar blood vessels ( P <0 001) Tet-treated CDH pups had a reduced percentage of muscularized intra-acinar arteries compared with CDH-NS animals Conclusions Medial hypertrophy is present in both the pre-acinar and intra-acinar arteries in the nitrofen-induced CDH rat model Tet treatment inhibits medial hypertrophy and reduces the percentage of muscularized intra-acinar vessels Prenatal Tet therapy may be efficacious in reducing the risk of PH in human newborns with CDH

Anti-proliferative and apoptotic effects of S1,a tetrandrine derivative,in human gastric cancer BGC-823 cells

The aim of the study was to investigate the anti-proliferation and apoptosis-inducing effects of S1, a novel tetrandrine derivative, in human gastric cancer BGC-823 cells and explore the possible mechanism of action. The anti-proliferative activity was determined by MTT assay; the induction of cell cycle arrest and apoptosis were detected by flow cytometry. Quantitative real time RT-PCR and Western blotting were used to evaluate the m RNA and protein expression levels in mitochondrial pathway. S1 significantly reduced cell viability and induced a G2/M phase arrest and apoptosis in dose- and time-dependent manner. Further studies showed that S1 increased m RNA and protein expression of Bax and the Bax/Bcl-2 ratio. Moreover, S1 decreased the protein expression of procaspase-9 and procaspase-3, suggesting that the induction of apoptosis may be related to the alteration of the ratio of Bax/Bcl-2 and the activation of caspases. These findings suggested that S1 merits further investigation as a novel therapeutic agent for the treatment of human gastric cancer.

Tetrandrine citrate eliminates imatinib-resistant chronic myeloid leukemia cells in vitro and in vivo by inhibiting Bcr-Abl/β-catenin axis

Objective:To evaluate the effects of tetrandrine citrate, a novel tetrandrine salt with high water solubility, on the growth of imatinib (IM)-resistant chronic myeloid leukemia (CML) in vitro and in vivo, and reveal action molecular mechanisms. Methods:Cell viability in vitro was measured using methyl thiazolyl tetrazolium (MTT) assay. CML cell growth in vivo was assessed using a xenograft model in nude mice. Bcr-Abl and β-catenin protein levels were determined using Western blotting. Bcr-Abl messenger RNA (mRNA) was measured by reverse transcription polymerase chain reaction (RT-PCR). Flow cytometry (FCM) was used to determine cell cycle status. Results:Tetrandrine citrate inhibited the growth of IM-resistant K562 cells, primary leukemia cells, and primitive CD34 + leukemia cells, and their inhibition concentration that inhibited 50% of target cells (IC 50 ) ranged from 1.20 to 2.97 μg/ml. In contrast, tetrandrine citrate did not affect normal blood cells under the same conditions, and IC 50 values were about 10.12-13.11 μg/ml. Oral administration of tetrandrine citrate caused complete regression of IM-resistant K562 xeno-grafts in nude mice without overt toxicity. Western blot results revealed that treatment of IM-resistant K562 cells with tetrandrine citrate resulted in a significant decrease of both p210 Bcr-Abl and β-catenin proteins, but IM did not affect the Bcr-Abl protein levels. Proteasome inhibitor, MG132, did not prevent tetrandrine-mediated decrease of the p210 Bcr-Abl protein. RT-PCR results showed that tetrandrine treatment caused a decrease of Bcr-Abl mRNA. FCM analysis indicated that tetrandrine induced gap 1 (G 1 ) arrest in CML cells. Conclusions:Tetrandrine citrate is a novel orally active tetrandrine salt with potent anti-tumor activity against IM-resistant K562 cells and CML cells. Tetrandrine citrate-induced growth inhibition of leukemia cells may be involved in the depletion of p210 Bcr-Abl mRNA and β-catenin protein.