Arene-Arene Coupled Disulfamethazines (or Sulfadiazine)-Phenanthroline-Metal(II) Complexes were Synthesized by In Situ Reactions and Inhibited the Growth and Development of Triple-Negative Breast Cancer through the Synergistic Effect of Antiangiogenesis, Anti-Inflammation, Pro-Apoptosis, and Cuproptosis.

The novel metal(II)-based complexes HA-Cu, HA-Co, and HA-Ni with phenanthroline, sulfamethazine, and aromatic-aromatic coupled disulfamethazines as ligands were synthesized and characterized. HA-Cu, HA-Co, and HA-Ni all showed a broad spectrum of cytotoxicity and antiangiogenesis. HA-Cu was superior to HA-Co and HA-Ni, and even superior to DDP, showing significant inhibitory effect on the growth and development of tripe-negative breast cancer in vivo and in vitro. HA-Cu exhibited observable synergistic effects of antiproliferation, antiangiogenesis, anti-inflammatory, pro-apoptosis, and cuproptosis to effectively inhibited tumor survival and development. The molecular mechanism was confirmed that HA-Cu could downregulate the expression of key proteins in the VEGF/VEGFR2 signaling pathway and the expression of inflammatory cytokines, enhance the advantage of pro-apoptotic protein Bax, and enforce cuproptosis by weakening the expression of FDX1 and enhancing the expression of HSP70. Our research will provide a theoretical and practical reference for the development of metal-sulfamethazine and its derivatives as chemotherapy drugs for cancer treatment.

SNTA1-deficient human cardiomyocytes demonstrate hypertrophic phenotype and calcium handling disorder.

BACKGROUND: α-1-syntrophin (SNTA1), a protein encoded by SNTA1, is highly expressed in human cardiomyocytes. Mutations in SNTA1 are associated with arrhythmia and cardiomyopathy. Previous research on SNTA1 has been based on non-human cardiomyocytes. This study was designed to identify the phenotype of SNTA1-deficiency using human cardiomyocytes. METHODS: SNTA1 was knocked out in the H9 embryonic stem cell line using the CRISPR-Cas9 system. H9SNTA1KO cells were then induced to differentiate into cardiomyocytes using small molecule inhibitors. The phenotypic discrepancies associated with SNTA1-deficient cardiomyocytes were investigated. RESULTS: SNTA1 was truncated at the 149th amino acid position of PH1 domain by a stop codon (TGA) using the CRISPR-Cas9 system. SNTA1-deficiency did not affect the pluripotency of H9SNTA1KO, and they retain their in vitro ability to differentiate into cardiomyocytes. However, H9SNTA1KO derived cardiomyocytes exhibited hypertrophic phenotype, lower cardiac contractility, weak calcium transient intensity, and lower level of calcium in the sarcoplasmic reticulum. Early treatment of SNTA1-deficient cardiomyocytes with ranolazine improved the calcium transient intensity and cardiac contractility. CONCLUSION: SNTA1-deficient cardiomyocytes can be used to research the etiology, pathogenesis, and potential therapies for myocardial diseases. The SNTA1-deficient cardiomyocyte model suggests that the maintenance of cardiac calcium homeostasis is a key target in the treatment of myocardial-related diseases.

Jolkinolide A and Jolkinolide B Inhibit Proliferation of A549 Cells and Activity of Human Umbilical Vein Endothelial Cells.

BACKGROUND Jolkinolide A (JA) and Jolkinolide B (JB) are diterpenoids extracted from the roots of Euphorbia fischeriana Steud and have been shown to have anti-tumor activity. However, their effects on the ability of tumor cells to invade blood vessels and metastasize remain largely unknown. Investigations into the effects of JA and JB on the angiogenesis of tumor tissues may facilitate the identification of new natural drugs with anti-tumor growth and metastasis activities. MATERIAL AND METHODS We used different concentrations of JA and JB (20 µg/ml, 40 µg/ml, 60 µg/ml, 80 µg/ml, and 100 µg/ml) to stimulate A549 cells and then studied the effects on the growth and metastasis of lung cancers. In addition, we used conditional media from A549 cells (A549-CM) stimulated by either JA or JB in different concentrations to culture human umbilical vein endothelial cells (HUVECs). RESULTS We found that both JA and JB significantly inhibited the Akt-STAT3-mTOR signaling pathway and reduced the expression of VEGF in A549 cells, but JB exhibited more significant inhibitory effects than JA. The JB-stimulated A549 cell conditional media had a greater inhibitory effect on the proliferation and migration of HUVECs than did the conditional media of JA-stimulated A549 cells. This effect gradually increased with increasing concentrations of either type of Jolkinolide. CONCLUSIONS Our results suggest that JA and JB inhibited VEGF expression in A549 cells through the inhibition of the Akt-STAT3-mTOR signaling pathway, and directly inhibited the proliferation and migration of HUVECs. These findings are of great significance for the development of new plant-derived chemotherapy agents for the treatment of cancer.

Identification of antioxidant activity of two new aromatic ring butyrolactone derivatives from Dictamnus dasycarpus Turcz.

The present study carried out a phytochemical investigation on the root barks of Dictamnus dasycarpus Turcz, leading to the isolation and characterization of two new aromatic ring butyrolactone derivatives, dasycarpusphenol acid A (1) and dasycarpusphenol acid B (2). Their structures were elucidated by using spectroscopic techniques and HR-FAB-MS. Compounds 1 and 2 exhibited antioxidant activity, with their IC50 values being 28.95 and 41.76 mg·mL-1, respectively.

TOX3 protein expression is correlated with pathological characteristics in breast cancer.

TOX3 is a newly identified gene that has been observed to correlate with breast cancer by genome-wide association studies (GWAS) in recent years. In addition, it has been noted that single-nucleotide polymorphisms (SNPs) in the TOX3 gene have a strong correlation with estrogen receptor (ER)-positive tumors. However, the role of TOX3 in breast carcinoma development is still unclear. There are limited studies on the subject of TOX3 mRNA expression in breast tumors and little information on the variation of TOX3 protein expression in relation to the clinical pathological features in breast cancer and healthy tissues. In this study, we characterize the protein expression of TOX3 in breast tumors with respect to various clinical and pathological characteristics and explore the correlation between TOX3 protein expression and ER-positive tumors. A breast cancer tissue microarray containing 267 human breast tumors and 25 healthy controls, breast cancer cell lines (ZR-75-1, MDA-MB-231, MCF-7 and Bcap-37) with positive or negative ER expression, tumor tissues and matched controls were used to analyze the protein expression levels of TOX3 by immunohistochemistry, western blot analysis and quantitative polymerase chain reaction. Among the 267 breast tumor specimens, ER expression was detected in 66 tumor tissues. The expression levels of TOX3 increased in breast carcinoma tissue compared with controls, and were higher in advanced carcinoma (T3 and T4), lymph node metastases tissues (N2) and stage III tissues. Furthermore, TOX3 protein expression was more intense in ER-positive tumors, but did not demonstrate a statistical significance. However, it was significantly increased in ER-positive breast cancer cell lines (ZR-75-1, MCF-7 and Bcap-37) compared with the MDA-MB-231 cell line, which had ER-negative expression. Our findings provide support to the hypothesis that TOX3 has a strong correlation with the development of breast cancer. The current study is likely to assist in investigating the mechanisms involved in breast cancer development.

[Effect of lupeol on migration and invasion of human breast cancer MDA-MB-231 cells and its mechanism].

In this study, we examined the inhibitory effects of lupeol, an extract of Euphorbia fischerana Steud, on human breast cancer MDA-MB-231 cells migration and invasion. Lupeol was found to inhibit the invasion of MDA-MB-231 in the cell adhesion assay, transwell test and wound healing assay. The expression of cyclooxygenase-2 (COX-2), matrix metalloproteinase-2 (MMP-2), -9 (MMP-9) and nuclear transcription factor-kappa B (NF-κB) p65 in breast cancer following treatment with different concentrations of lupeol was analyzed with Western blot. Lupeol inhibited the migration and invasion of MDA-MB-231 cells in a dose- dependent manner in vitro (P < 0.05). The expression of COX-2, MMP-2, MMP-9 and NF-κB p65 levels was significantly down-regulated. These observations suggest that lupeol can inhibit the abilities of invasion of MDA-MB-231 cells by inhibiting the protein expression of COX-2, MMP-2 and MMP-9. Its mechanism may be related to inhibition of the nuclear NF-κB signal pathway.

[Effect of Resveratrol on Isoproterenol Induced Cardiomyocyte Apoptosis Rats].

OBJECTIVE: To observe the effect and mechanism of resveratrol (Res) on isoprotere- nol (ISO) induced cardiomyocyte apoptosis rats. METHODS: Primary cultured neonatal cardiomyocyte ap- optosis rat model was established using ISO. Apoptosis cells were then randomly divided into 4 groups, i. e., the normal control group (non-serum DMEM culture fluid) , the model group (non-serum DMEM culture fluid + ISO 1 µmol/L for 48 h) , the Res + ISO group (ISO 1 µmol/L + Res 50 µmoI/L for 48 h) , the Res control group. (non-serum DMEM culture fluid + Res 50 l_mol/L). The apoptosis rate was measured by Hochest33258 staining. Ultrastructural changes of cardiomyocyte were observed by electron microscope. Leakage of lactate dehydrogenase (LDH) in the culture fluid was measured. Protein expressions of BcI-2 and Bax were detected using Western blot. Results The count of cardiomyocytes were reduced and the nucleus shape was irregular. The apoptosis bodies were visible and the apoptosis rate was increased in the model group. The cell membrane was complete with clear nuclear membrane in the Res + ISO group and the Res control group. Nuclear chromatin was concentrated and cell injured degree was attenuated in the Res +ISO group and the Res control group. Compared with the normal control group, the apoptosis rate and LDH leakage increased, the protein expression of Bcl-2 was down-regulated, and the expression of Bax was up-regulated in the model group (P <0. 05, P <0. 01). Compared with the model group, the apoptosis rate and LDH leakage decreased, the protein expression of Bcl-2 was up-regulated, and the expression of Bax was down-regulated in the Res + ISO group and the Res control group (P <0. 05). CONCLUSION: Res could obviously attenuate ISO induced cardiomyocyte apoptosis, and its mechanism might be associated with reversing protein expressions of Bcl-2 and Bax.

[Effect of ethyl gallate on invasion abilities and its mechanism of breast cancer MDA-MB-231 cells].

This study is to investigate the effect of ethyl gallate on invasion capabilities and its mechanism of breast cancer MDA-MB-231 cells. Using cell adhesion and transwell assay, separately, the effects of ethyl gallate on the invasion of MDA-MB-231 cells were measured. The Akt-NF-κB signal pathway protein expressions were analyzed with Western blot. Also, the mRNA levels of MMP-9 and MMP-2 were analyzed by RT-PCR. Ethyl gallate inhibited the abilities of motility, adhesion and invasion of breast cancer MDA-MB-231 cells in vitro (P<0.05), inhibited the mRNA levels of MMP-9, MMP-2, phosphorylation of AKt and protein expression of NF-κB. It is concluded that ethyl gallate can inhibit the abilities of invasion of breast cancer in vitro by inhibiting the mRNA levels of MMP-9/MMP-2, phosphorylation of Akt and protein expression of NF-κB.

12-Deoxyphorbol 13-palmitate inhibit VEGF-induced angiogenesis via suppression of VEGFR-2-signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: 12-Deoxyphorbol 13-palmitate (G) is one toxic compound isolated from Euphorbia fischeriana, an Asian spice used for cancer treatment as a folk remedy. However, whether 12-deoxyphorbol 13-palmitate affects angiogenesis remains unclear. AIM OF THE STUDY: To explore the in vitro and in vivo antiangiogenic effects of 12-deoxyphorbol 13-palmitate and its underlying mechanisms. MATERIALS AND METHODS: We explored antigenic functions in human umbilical vein endothelial cells (HUVEC) by 12-deoxyphorbol 13-palmitate, including proliferation, migration and metastasis through matrigel plug assay, chorioallantoic membrane assay, in vitro migration assay, tube formation assay, motility assay. Antibody chip was applied to screen differentially expressed proteins modulated by 12-deoxyphorbol 13-palmitate, and was further confirmed by RT-PCR and western blot analysis. Tumor xenograft mice were applied to investigate whether 12-deoxyphorbol 13-palmitate could inhibit microvessel density in vivo. RESULTS: 12-Deoxyphorbol 13-palmitate inhibited vascular endothelial growth factor (VEGF)-induced angiogenic processes in vitro, such as proliferation, in vitro migration, and tube formation of HUVEC. In chorioallantoic membrane assay, 12-deoxyphorbol 13-palmitate significantly inhibited neovessel formation. Antibody chip technology demonstrated decreased expression of TIMP-1, TIMP-2, VEGF, basic fibroblast growth factor (bFGF), matrix metalloproteinases (MMP)-2, VEGFR-2 and VEGFR-3 proteins in HUVEC after 24h. In addition, 12-deoyphorbol 13-palmitate inhibited the in vivo growth of MCF-7 cells in grafted mouse model. Immunohistochemistry staining showed decreased microvessel density (CD31) and attenuated VEGFR-2 signaling pathways by 12-deoxyphorbol 13-palmitate. CONCLUSION: 12-Deoxyphorbol 13-palmitate may be utilized to target active angiogenesis through VEGF/VEGFR2 signal pathway for cancer.

Jolkinolide B induces apoptosis in MCF-7 cells through inhibition of the PI3K/Akt/mTOR signaling pathway.

The aim of this study was to explore the molecular mechanisms of jolkinolide B (JB), which is extracted from the root of Euphorbia fischeriana Steud. In this study, we found that JB, a diterpenoid from the traditional Chinese medicinal herb, strongly inhibited the PI3K/Akt/mTOR signaling pathway. Furthermore, we evaluated the effects of JB on the proliferation and apoptosis of MCF-7 human breast cancer cells. Our results showed significant induction of apoptosis in MCF-7 cells incubated with JB. The viability of the MCF-7 cells was assessed by MTT assay. Flow cytometry was used to detect apoptosis and cell cycle analysis. Transmission electron microscopy (TEM) analysis was used to observe cell morphology. MCF-7 cells were subcutaneously inoculated into nude mice to study the in vivo antitumor effects of JB. The growth of MCF-7 cells was inhibited and arrested in the S phase by JB. The data showed significantly decreased tumor volume and weight in nude mice inoculated with MCF-7 cells. In addition, treatment with JB was able to induce downregulation of cyclinD1, cyclinE, mTOR, p-PI3K and p-Akt, and upregulation of PTEN and p-eIF4E. Collectively, JB-induced apoptosis of MCF-7 cells occurs through the PI3K/Akt/mTOR signaling pathway. Furthermore, the PI3K/Akt signaling cascade plays a role in the induction of apoptosis in JB-treated cells. These observations suggest that JB may have therapeutic applications in the treatment of cancer.

12-Deoxyphorbol 13-palmitate mediated cell growth inhibition, G2-M cell cycle arrest and apoptosis in BGC823 cells.

The highly toxic monomer 12-deoxyphorbol 13-palmitate (G) was extracted from the roots of Euphorbia fischeriana. Our experimental data confirmed studies showing that 12-deoxyphorbol 13-palmitate had certain antitumor activities. The MTT method, soft agar experiments, and nude mouse tumor experiments proved that 12-deoxyphorbol 13-palmitate inhibited the growth of BGC823 cells. We found that the drug could induce cell cycle arrest at the G2-M checkpoint in BGC823 cells. The compound also induced apoptosis as assayed by Annexin-V-FITC/PI dual labeling, AO/EB dyeing, and caspase-3 and caspase-9 activity. The reduction in expression of cyclin B1 protein and the increased activity of reactive oxygen species were observed in BGC823 cells treated with 12-deoxyphorbol 13-palmitate for 24 h. In addition, we found down-regulation of cdc2/cyclin B, cyclin A and p-chk1 in tumor cells. There was also up-regulation of Bax, p53, p21, and IκB-α and down-regulation of Bcl-2 and NF-κB by WB. Our studies may define a novel mechanism by which 12-deoxyphorbol 13-palmitate inhibits tumor cell growth and induces apoptosis. The results of our current studies provided strong experimental evidence for the use of 12-deoxyphorbol 13-palmitate as a potential preventive and/or therapeutic agent in cancer.

Hydroxysafflor yellow A attenuates carbon tetrachloride-induced hepatic fibrosis in rats by inhibiting ERK5 signaling.

Hepatic stellate cells (HSCs) undergo activation during the development of liver fibrosis. Transcription factor myocyte enhancer factor (MEF2) 2C plays a key role in this process. In the present study, we investigated the effect of hydroxysafflor yellow A (HSYA) on hepatic fibrosis and further investigated potential mechanisms in vivo. Sprague-Dawley rats were administered with CCl(4) together with or without HYSA for 12 weeks. The effect of HYSA on hepatic fibrosis was evaluated using hematoxylin-eosin and Van Gieson staining. Messenger RNA expression was quantified by real-time polymerase chain reaction, and protein was quantified by Western blot or immunohistochemistry. Our results revealed that CCl(4) treatment induced micronodular hepatic fibrosis with a pronounced deposition of collagen fibers. Treatment with HYSA resulted in a significant decrease in fibrosis, protein expression of α-SMA, and MEF-2C gene expression. This was accompanied by a decreased expression of Tß-RI, Tß-RII, MEKK3, MEK5, and phosphorylation of ERk5. HYSA alone had no effect on the measured parameters. Our findings demonstrate that HSYA protected, at least in part, the rat liver from CCl(4)-caused fibrogenesis through inhibition of hepatic stellate cell (HSC) activation, attenuation of transforming growth factor beta (TGF-ß) signaling. HSYA may become a novel and promising agent for the inhibition of hepatic fibrosis.

REDD1 expression in placenta during human gestation.

The aim of the study was to detect the regulated in development and DNA responses (REDD1) in human placentas throughout different gestational ages (GAs) and to correlate REDD1 with preeclampsia (PE). In experiments, REDD1 messenger RNA and protein expression levels throughout the gestation were determined using immunohistochemistry, quantitative reverse transcriptase polymerase chain reaction, and Western blot. Furthermore, REDD1 protein levels in placenta were also compared between normal outcome pregnancies (n = 20, GA >37 weeks) and PE pregnancies (n = 29), which includes early onset PE; n = 15, GA: 24-33 weeks) and late onset PE (n = 14, GA: 34-39 weeks) by Western blot. As a result, REDD1 protein was predominantly observed in the cytoplasm of trophoblasts. Moreover, higher levels of REDD1 were found not only at earlier gestational stage but also in the PE groups (P < .05). In conclusion, REDD1 may play an important role in maintaining the normal function of placenta during various stages of gestation and predicted that the increase in REDD1 is related to the pathogenesis of PE.

Hydroxysafflor yellow A induces apoptosis in activated hepatic stellate cells through ERK1/2 pathway in vitro.

A key feature in the molecular pathogenesis of liver fibrosis requires maintenance of the activated hepatic stellate cells (HSCs) phenotype by inhibition of apoptosis. The induction of apoptosis in activated HSCs has been proposed as an antifibrotic treatment strategy. This study aims at evaluating the effect of hydroxysafflor yellow A (HSYA) on apoptosis of culture-activated HSCs and further elucidating the underlying mechanisms. Primary HSCs were isolated from rats. The analysis of the cell cycle be performed by flow cytometry, detection of apoptosis by Annexin V-FITC/ PI staining, and the results were confirmed by DNA fragmentation, and cleavage of caspase-3 and poly (ADP-ribose) polymerase (PARP). Real-time polymerase chain reaction and Western blotting were used to analyze the expression of genes. Our results revealed that HSYA significantly induced apoptosis in a dose- and time-dependent manner. HSYA suppresses the activation of ERK1/2 and ERK1/2-regulated gene expression, including Bcl-2, Cytochrome c, caspase-9, and caspase-3, leading to the enhancement of apoptosis. Pharmacological blockade of ERK1/2 kinase abrogation this action of HSYA. Our data provide a molecular basis for the anti-hepatic fibrosis activity of HSYA.

Two new compounds from Dictamnus dasycarpus.

Two new compounds, one new pyrrolidine alkaloid and one new eudesmane-type sesquiterpene derivative, named, respectively, as dictamnaindiol and dictamnadiol, were isolated from the EtOAc soluble fraction of the ethanolic extract from the root barks of Dictamnus dasycarpus. Their structures were elucidated as (3α,4ß)-3-(6-ethoxy-6-(4-hydroxyphenyl)methyl)-4-(4-hydroxyphenyl)-1-methyl-pyrrolidin-2-one (1) and (1R, 4S, 7S, 10R)-1,11-dihydroxyl-4,14-epoxy-5(6)-eudesmene (2) on the basis of their spectral and chemical analysis.

Three new compounds from Dictamnus dasycarpus.

Phytochemical investigation of the ethyl acetate extracts from root barks of Dictamnus dasycarpus led to the isolation of three new compounds, named as dasycarpusenester A (1), dasycarpusester B (2), dasycarpusacid (3). Their structures were elucidated as (2S)-4-(2,2-dimethyl-5-oxotetrahydrofuran-3-yl)-2-hydroxypent-3-enoic acid methyl ester (1), (2R)-4-(2,2-dimethyl-5-oxotetrahydrofuran-3-yl)-2-hydroxypent-3-anoic acid methyl ester (2), and (2S)-4-(2,2-dimethyl-5-oxotetrahydrofuran-3-yl)-2-hydroxypent-3-anoic acid (3), respectively, on the basis of modern spectroscopic methods and chemical analysis.

Phytochemicals and bioactivities of Anemone raddeana Regel: a review.

Anemone raddeana, usually called as'"Toujian Liang" in China, is an Anemone herb belonging to the Ranunculaceae family. Until now there are in total 67 of chemical components identified including triterpenoids, steroids, lactones, fats and oils, saccharide and alkaloids. A broad spectrum of pharmacological activity of A. raddeana compounds have been reported, such as antitumor, antimicrobial, anti-inflammatory, sedative and analgesic activites, as well as anti-convulsant and anti-histamine effects. In view of this, we initiated this short review to present the phytochemical and pharmacological profile of A. raddeana to support future studies in this discipline.

Beta-asarone attenuates beta-amyloid-induced apoptosis through the inhibition of the activation of apoptosis signal-regulating kinase 1 in SH-SY5Y cells.

Beta-amyloid (Abeta) toxicity has been postulated to initiate synaptic loss and subsequent neuronal degeneration seen in Alzheimer's disease (AD). We previously demonstrated that beta-asarone improves cognitive function by suppressing neuronal apoptosis in vivo. In this study, we assessed the neuroprotective effects of beta-asarone against the toxicity of Abeta in relation to the mitochondria-mediated cell death process, and to elucidated the role of the ASK1/MKK7/JNK and mitochondrial pathways in beta-asarone-induced neuroprotection in SH-SY5Y cells. Our results show that beta-asarone afforded protection against Abeta-induced toxicity by inhibiting apoptosis in SH-SY5Y cells. This result was also confirmed by caspase-9 and caspase-3 activity assays. Expression of p-ASK1, p-MKK7, p-JNK, Bax, Bad, and cytochrome c release decreased after pretreatment with beta-asarone in SH-SY5Y cells exposed to A1-42. Interestingly, these effects of beta-asarone against Abeta1-42 insult were enhanced by ASK1 siRNA. These findings suggest that beta-asarone prevents Abeta1-42-induced neurotoxicity through attenuating neuronal apoptosis, and might be a potential preventive or therapeutic agent for AD.

Downregulation of the ornithine decarboxylase/polyamine system inhibits angiotensin-induced hypertrophy of cardiomyocytes through the NO/cGMP-dependent protein kinase type-I pathway.

BACKGROUND: Polyamines and nitric oxide (NO) have been involved in the pathogenesis of cardiac hypertrophy. NO can regulate cardiac ion channels by direct actions on G-proteins and adenyl cyclase. The present study was undertaken to elucidate the molecular mechanism of interactions with polyamines and NO in cardiac hypertrophy. METHODS: Cardiaomyocyte hypertrophy was induced by angiotensinII (AngII). Hypertrophy was estimated by cell-surface area, atrial natriuretic peptide (ANP) mRNA expression, and the immunofluorescence of phalloidin. Pretreatment with alpha-difluoromethylornithine (DFMO) was done to deplete putrescine; KT5823 pretreatment was carried out to block the nitric oxide/cGMP-dependent protein kinase type-I (NO/PKG-I) pathway. Expressions of endothelial nitric oxide synthase (eNOS), PKG-I, c-fos and c-myc were analyzed by western blotting and immunofluorescence. The intracellular concentration of free calcium ([Ca2+](i)) was determined by confocal laser scanning microscopy. RESULTS: Hypertrophy of cardiomyocytes was induced by AngII, this caused an increase in putrescine, spermidine and total polyamine pool in association with a decreased level of NO. Expressions of eNOS and PKG-I were down-regulated, [Ca2+](i) was increased, and expressions of c-Fos and c-Myc upregulated. DFMO reversed these changes induced by AngII. CONCLUSIONS: Downregulation of polyamines inhibits cardiomyocyte hypertrophy, which is closely related to [Ca2+](i) and the NO/PKG-I pathway.