Sodium Ferulate Inhibits Rat Cardiomyocyte Hypertrophy Induced by Angiotensin II Through Enhancement of Endothelial Nitric Oxide Synthase/Nitric Oxide/Cyclic Guanosine Monophosphate Signaling Pathway.

ABSTRACT: Sodium ferulate (SF) is the sodium salt of ferulic acid, which is one of the effective components of Angelica sinensis and Lignsticum chuanxiong , and plays an important role in protecting the cardiovascular system. In this study, myocardial hypertrophy was induced by angiotensin II 0.1 µmol/L in neonatal Sprague-Dawley rat ventricular myocytes. Nine groups were designed, that is, normal, normal administration, model, L-arginine (L-arg 1000 µmol/L), SF (50, 100, 200 µmol/L) group, and N G -nitro-L-arg-methyl ester 1500 µmol/L combined with SF 200 µmol/L or L-arg 1000 µmol/L group, respectively. Cardiomyocyte hypertrophy was confirmed by observing histological changes and measurements of cell diameter, protein content and atrial natriuretic factor, and ß-myosin heavy chain levels of the cells. Notably, SF could inhibit significantly myocardial hypertrophy of neonatal rat cardiomyocytes in a concentration-dependent manner without producing cytotoxicity, and the levels of nitric oxide, NO synthase (NOS), endothelial NOS, and cyclic guanosine monophosphate were increased, but the level of cyclic adenosine monophosphate was decreased in cardiomyocytes. Simultaneously, levels of protein kinase C beta, Raf-1, and extracellular regulated protein kinase 1/2 (ERK1/2) were downregulated, whereas levels of mitogen-activated protein kinase phosphatase-1 were significantly upregulated. All the beneficial effects of SF were blunted by N G -nitro-L-arg-methyl ester. Overall, these findings reveal that SF can inhibit angiotensin II-induced myocardial hypertrophy of neonatal rat cardiomyocytes, which is closely related to activation of endothelial NOS/NO/cyclic guanosine monophosphate, and inhibition of protein kinase C and mitogen-activated protein kinase signaling pathways.

Effects of Sodium Ferulate on Cardiac Hypertrophy Are via the CaSR-Mediated Signaling Pathway.

As a common complication of many cardiovascular diseases, cardiac hypertrophy is characterized by increased cardiac cell volume, reorganization of the cytoskeleton, and the reactivation of fetal genes such as cardiac natriuretic peptide and ß-myosin heavy chain. Cardiac hypertrophy is a distinguishing feature of some cardiovascular diseases. Our previous study showed that sodium ferulate (SF) alleviates myocardial hypertrophy induced by coarctation of the abdominal aorta, and these protective effects may be related to the inhibition of protein kinase C (PKC) and mitogen-activated protein kinase (MAPK) signaling pathways. This study investigated the inhibitory effect and mechanism of SF on myocardial hypertrophy in spontaneously hypertensive rats (SHRs). The effects of SF on cardiac hypertrophy were evaluated using echocardiographic measurement, pathological analysis, and detection of atrial natriuretic peptide (ANP) and ß-myosin heavy chain (ß-MHC) expression. To investigate the mechanisms underlying the anti-hypertrophic effects of SF, the calcium-sensing receptor (CaSR), calcineurin (CaN), nuclear factor of activated T cells 3 (NFAT3), zinc finger transcription factor 4 (GATA4), protein kinase C beta (PKC-ß), Raf-1, extracellular signal-regulated kinase 1/2 (ERK 1/2), and mitogen-activated protein kinase phosphatase-1 (MKP-1) were detected by molecular biology techniques. Treatment with SF ameliorated myocardial hypertrophy in 26-week-old SHRs. In addition, it downregulated the levels of ANP, ß-MHC, CaSR, CaN, NFAT3, phosphorylated GATA4 (p-GATA4), PKC-ß, Raf-1, and p-ERK 1/2; and upregulated the levels of p-NFAT3 and MKP-1. These results suggest that the effects of SF on cardiac hypertrophy are related to regulation of the CaSR-mediated signaling pathway.

Comparative Immunohistochemistry of Placental Corticotropin-Releasing Hormone and the Transcription Factor RelB-NFκB2 Between Humans and Nonhuman Primates.

The transcription factor RelB-NFκB2, activated by the noncanonical NFκB pathway, positively regulates corticotropin-releasing hormone (CRH) and prostaglandin production in the term human placenta and may play an important role in the timing of human parturition. Here we explored whether RelB-NFκB2 signaling plays a role in parturition in nonhuman anthropoid primates. We performed immunohistochemical staining to assess the correlation between CRH and nuclear activity of RelB-NFκB2 heterodimers in term placentas from humans, 3 catarrhine primate species, and a single platyrrhine primate species. Consistent with our previous studies, the human placenta showed cytoplasmic staining for CRH and nuclear staining for RelB-NFκB2. Similar staining patterns were noted in the 3 catarrhine primates (chimpanzee, baboon, and rhesus macaque). The platyrrhine (marmoset) placentas stained positively for CRH and RelB but not for NFκB2. Catarrhine (but not platyrrhine) nonhuman primate term placentas demonstrate the same CRH staining and nuclear localization patterns of RelB and NFκB2 as does human placenta. These results suggest that catarrhine primates, particularly rhesus macaques, may serve as useful animal models to study the biologic significance of the noncanonical NFκB pathway in human pregnancy.

Fas signaling in thyroid carcinomas is diverted from apoptosis to proliferation.

PURPOSE: The death receptor Fas is present in thyroid carcinomas, yet fails to trigger apoptosis. Interestingly, Fas has been reported to be actually overexpressed in papillary thyroid carcinomas, suggesting that it may confer a survival advantage. EXPERIMENTAL DESIGN: We investigated the expression and activation status of Fas pathway mediators in thyroid carcinoma cell lines and tumor specimens. RESULTS: All cell lines tested express Fas-associated death domain, procaspase-8, procaspase-9, and procaspase-3; resistance to Fas-mediated apoptosis could not be attributed to lack of any of these apoptosis mediators. Moreover, Fas death domain mutations were not found in our study. The proteasome inhibitors MG132 and PS-341 (bortezomib, Velcade), which lead to accumulation of the nuclear factor kappaB (NF-kappaB) inhibitor IkappaB, did not sensitize SW579 cells to Fas-mediated apoptosis, suggesting that resistance to Fas-mediated apoptosis is not due to proteasome or NF-kappaB activity. Cross-linking of Fas in vitro induced recruitment of Fas-associated death domain-like interleukin-1beta-converting enzyme inhibitory protein (FLIP) instead of procaspase-8. Inhibition of FLIP expression with a FLIP antisense oligonucleotide resulted in significant sensitization to Fas-mediated apoptosis. Fas cross-linking promoted BrdUrd incorporation; activated the mitogen-activated protein kinase/extracellular signal-regulated kinase kinase/extracellular signal-regulated kinase, NF-kappaB, and activator protein-1 pathways in thyroid carcinoma cells in vitro; and protected cells from tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis. We also found that good prognosis papillary thyroid carcinoma specimens exhibited higher immunoreactivity for cleaved (activated) caspase-8 than poor prognosis tumors. CONCLUSIONS: In thyroid carcinomas, the proteolytic cleavage and activation of caspase-8 depends on the balance between expression levels for procaspase-8 and FLIP and correlates with favorable clinical prognosis. Fas may actually stimulate proliferation and confer a survival advantage to thyroid cancer cells.