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Peroxisome proliferator-activated receptor α (PPARα), a ligand-activated nuclear receptor critical for systemic lipid homeostasis, has been shown closely related to cardiac remodeling. However, the roles of cardiomyocyte PPARα in pressure overload-induced cardiac remodeling remains unclear because of lacking a cardiomyocyte-specific Ppara-deficient (Ppara(ΔCM)) mouse model. This study aimed to determine the specific role of cardiomyocyte PPARα in transverse aortic constriction (TAC)-induced cardiac remodeling using an inducible Ppara(ΔCM) mouse model. Ppara(ΔCM) and Ppara(fl/fl) mice were randomly subjected to sham or TAC for 2 weeks. Cardiomyocyte PPARα deficiency accelerated TAC-induced cardiac hypertrophy and fibrosis. Transcriptome analysis showed that genes related to fatty acid metabolism were dramatically downregulated, but genes critical for glycolysis were markedly upregulated in Ppara(ΔCM) hearts. Moreover, the hypertrophy-related genes, including genes involved in extracellular matrix (ECM) remodeling, cell adhesion, and cell migration, were upregulated in hypertrophic Ppara(ΔCM) hearts. Western blot analyses demonstrated an increased HIF1α protein level in hypertrophic Ppara(ΔCM) hearts. PET/CT analyses showed an enhanced glucose uptake in hypertrophic Ppara(ΔCM) hearts. Bioenergetic analyses further revealed that both basal and maximal oxygen consumption rates and ATP production were significantly increased in hypertrophic Ppara(fl/fl) hearts; however, these increases were markedly blunted in Ppara(ΔCM) hearts. In contrast, hypertrophic Ppara(ΔCM) hearts exhibited enhanced extracellular acidification rate (ECAR) capacity, as reflected by increased basal ECAR and glycolysis but decreased glycolytic reserve. These results suggest that cardiomyocyte PPARα is crucial for the homeostasis of both energy metabolism and ECM during TAC-induced cardiac remodeling, thus providing new insights into potential therapeutics of cardiac remodeling-related diseases.

Tamoxifen (TMX) is an antiestrogen drug that is used in the treatment and prevention of all stages of estrogen-dependent breast cancer. Adverse effects of TMX include hepatotoxicity. In this study, we investigated the therapeutic effects of osthole, isolated from medicinal plants especially Fructus Cnidii, on TMX-induced acute liver injury in mice. Mice were injected with osthole (100 mg/kg, ip) or vehicle, followed by TMX (90 mg/kg, ip) 24 h later. We showed that a single injection of TMX-induced liver injury and oxidative stress. Pretreatment with osthole attenuated TMX-induced liver injury evidenced by dose-dependent reduction of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities. Pretreatment with osthole also blunted TMX-induced oxidative stress, evidenced by significant increase of reduced glutathione (GSH) as well as reduction of malondialdehyde (MDA) and hydrogen peroxide (H(2)O(2)). Consistently, osthole significantly enhanced the expressions of antioxidant genes (GPX1, SOD2, GCL-c, and G6pdh), but suppressed those of pro-oxidant genes (NOX2 and ACOX). Furthermore, osthole inhibited the production of inflammatory cytokines, reduced the metabolic activation of TMX, and promoted its clearance. We further revealed that osthole elevated hepatic cAMP and cGMP levels, but inhibition of PKA or PKG failed to abolish the hepatoprotective effect of osthole. Meanwhile, prominent phosphorylation of p38 was observed in liver in response to TMX, which was significantly inhibited by osthole. Pretreatment with SB203580, a p38 inhibitor, significantly attenuated TMX-induced increase of ALT and AST activities, reduced oxidative stress, and reversed the alterations of gene expression caused by TMX. Moreover, pretreatment with L-buthionine sulfoximine (BSO), an inhibitor of GSH synthesis, partly reversed the effect of osthole on TMX-induced liver injury. Consistently, pretreatment with N-acetyl-L-cysteine (NAC) significantly attenuated TMX-induced increase in ALT and AST activities. Notably, both BSO and NAC had no detectable effect on the phosphorylation levels of p38. Collectively, our results suggest that osthole prevents TMX hepatotoxicity by suppressing p38 activation and subsequently reducing TMX-induced oxidative damage.

Our previous studies confirm that exogenous reduced nicotinamide adenine dinucleotide phosphate (NADPH) exerts a neuroprotective effect in animal models of ischemic stroke, and its primary mechanism is related to anti-oxidative stress and improved energy metabolism. However, it is unknown whether nicotinamide adenine dinucleotide (NADH) also plays a neuroprotective role and whether NADPH is superior to NADH against ischemic stroke? In this study we compared the efficacy of NADH, NADPH, and edaravone in ameliorating brain injury and metabolic stress in ischemic stroke. Transient middle cerebral artery occlusion/reperfusion (t-MCAO/R) mouse model and in vitro oxygen glucose deprivation/reoxygenation (OGD/R) model were established. The mice were intravenously administered the optimal dose of NADPH (7.5 mg/kg), NADH (22.5 mg/kg), or edaravone (3 mg/kg) immediately after reperfusion. We showed that the overall efficacy of NADPH in ameliorating ischemic injury was superior to NADH and edaravone. NADPH had a longer therapeutic time window (within 5 h) after reperfusion than NADH and edaravone (within 2 h) for ischemic stroke. In addition, NADPH and edaravone were better in alleviating the brain atrophy, while NADH and NADPH were better in increasing the long-term survival rate. NADPH showed stronger antioxidant effects than NADH and edaravone; but NADH was the best in terms of maintaining energy metabolism. Taken together, this study demonstrates that NADPH exerts better neuroprotective effects against ischemic stroke than NADH and edaravone.

Acetaminophen (APAP) overdose leads to severe hepatotoxicity. Osthole, a natural coumarin found in traditional Chinese medicinal herbs, has therapeutic potential in the treatment of various diseases. In this study, we investigated the effects of osthole against APAP-induced hepatotoxicity in mice. Mice were administered osthole (100 mg·kg-1·d-1, ip) for 3 d, then on the fourth day APAP (300 mg/kg, ip) was co-administered with osthole. The mice were euthanized post-APAP, their serum and livers were collected for analysis. Pretreatment with osthole significantly attenuated APAP-induced hepatocyte necrosis and the increases in ALT and AST activities. Compared with the mice treated with APAP alone, osthole pretreatment significantly reduced serum MDA levels and hepatic H2O2 levels, and improved liver GSH levels and the GSSG-to-GSH ratio. Meanwhile, osthole pretreatment markedly alleviated the APAP-induced up-regulation of inflammatory cytokines in the livers, and inhibited the expression of hepatic cytochrome P450 enzymes, but it increased the expression of hepatic UDP-glucuronosyltransferases (UGTs) and sulfotransferases (SULTs). Furthermore, osthole pretreatment reversed APAP-induced reduction of hepatic cAMP levels, but pretreatment with H89, a potent selective PKA inhibitor, failed to abolish the beneficial effect of osthole, whereas pretreatment with L-buthionine sulfoximine, a GSH synthesis inhibitor, abrogated the protective effects of osthole on APAP-induced liver injury, and abolished osthole-caused alterations in APAP-metabolizing enzymes. In cultured murine primary hepatocytes and Raw264.7 cells, however, osthole (40 μmol/L) did not alleviate APAP-induced cell death, but it significantly suppressed APAP-caused elevation of inflammatory cytokines. Collectively, we have demonstrated that osthole exerts a preventive effect against APAP-induced hepatotoxicity by inhibiting the metabolic activation of APAP and enhancing its clearance through an antioxidation mechanism.

To investigate the effects of piperlongumine (PL), an anticancer alkaloid from long pepper plants, on the primary myeloid leukemia cells from patients and the mechanisms of action.Human BM samples were obtained from 9 patients with acute or chronic myeloid leukemias and 2 patients with myelodysplastic syndrome (MDS). Bone marrow mononuclear cells (BMMNCs) were isolated and cultured. Cell viability was determined using MTT assay, and apoptosis was examined with PI staining or flow cytometry. ROS levels in the cells were determined using DCFH-DA staining and flow cytometry. Expression of apoptotic and autophagic signaling proteins was analyzed using Western blotting.PL inhibited the viability of BMMNCs from the patients with myeloid leukemias (with IC50 less than 20 μmol/L), but not that of BMMNCs from a patient with MDS. Furthermore, PL (10 and 20 μmol/L) induced apoptosis of BMMNCs from the patients with myeloid leukemias in a dose-dependent manner. PL markedly increased ROS levels in BMMNCs from the patients with myeloid leukemias, whereas pretreatment with the antioxidant N-acetyl-L-cysteine abolished PL-induced ROS accumulation and effectively reduced PL-induced cytotoxicity. Moreover, PL markedly increased the expression of the apoptotic proteins (Bax, Bcl-2 and caspase-3) and autophagic proteins (Beclin-1 and LC3B), and phosphorylation of p38 and JNK in BMMNCs from the patients with myeloid leukemias, whereas pretreatment with the specific p38 inhibitor SB203580 or the specific JNK inhibitor SP600125 partially reversed PL-induced ROS production, apoptotic/autophagic signaling activation and cytotoxicity.Piperlongumine induces apoptotic and autophagic death of the primary myeloid leukemia cells from patients via activation of ROS-p38/JNK pathways.

Osthole, a natural coumarin found in traditional Chinese medicinal plants, has shown multiple biological activities. In the present study, we investigated the preventive effects of osthole on inflammatory bowel disease (IBD). Colitis was induced in mice by infusing TNBS into the colonic lumen. Before TNBS treatment, the mice received osthole (100 mg·kg-1·d-1, ip) for 3 d. Pretreatment with osthole significantly ameliorated the clinical scores, colon length shortening, colonic histopathological changes and the expression of inflammatory mediators in TNBS-induced colitis. Pretreatment with osthole elevated serum cAMP levels; but treatment with the PKA inhibitor H89 (10 mg·kg-1·d-1, ip) did not abolish the beneficial effects of osthole on TNBS-induced colitis. In mouse peritoneal macrophages, pretreatment with osthole (50 μmol/L) significantly attenuated the LPS-induced elevation of cytokines at the mRNA level; inhibition of PKA completely reversed the inhibitory effects of osthole on IL-1β, IL-6, COX2, and MCP-1 but not on TNFα. In Raw264.7 cells, the p38 inhibitor SB203580 markedly suppressed LPS-induced upregulation of the cytokines, whereas the PKA inhibitors H89 or KT5720 did not abolish the inhibitory effects of SB203580. Moreover, in LPS-stimulated mouse peritoneal macrophages, SB203580 strongly inhibited the restored expression of IL-1β, IL-6, COX2, and MCP-1, which was achieved by abolishing the suppressive effects of osthole with the PKA inhibitors. Western blot analysis showed that osthole significantly suppressed the phosphorylation of p38, which was induced by TNBS in mice or by LPS in Raw264.7 cells. Inhibition of PKA partially reversed the suppressive effects of osthole on p38 phosphorylation in LPS-stimulated cells. Collectively, our results suggest that osthole is effective in the prevention of TNBS-induced colitis by reducing the expression of inflammatory mediators and attenuating p38 phosphorylation via both cAMP/PKA-dependent and independent pathways, among which the cAMP/PKA-independent pathway plays a major role.

To prepare a redispersible, dry emulsion (DE) and investigate whether it can improve intestinal stability and oral absorptive efficiency of the poorly water-soluble lovastatin (Lov).Phosal 53 MCT, Tween 80, and starch sodium octenyl succinate were employed as the oil phase, emulsifying agent, and matrix material, respectively. The redispersible, DE of Lov (Lov-DE) was prepared by spray drying the submicron emulsion of Lov. The characteristics of DE and the in vitro drug release were studied. The protective effects on the metabolism of Lov- DE and reference formulations, including the Lov suspension and the hydroxypropyl-beta-cyclodextrin (CD) complex were investigated in microsomes and the gut wall of male Sprague-Dawley (SD) rats. The bioavailability in SD rats was evaluated simultaneously.Lov-DE in distilled water was reconstituted compared with the submicron emulsion of Lov before spray drying, and remained almost unchanged after 3 months' storage at room temperature. Compared with the Lov suspension, the in vitro Lov dissolution of both the redispersible, DE and CD complex increased obviously. Compared with control formulations, the metabolism studies carried out in vitro and in vivo confirmed that the redispersible, DE presented remarkable protective effects as indicated by the decreased metabolism rate of Lov. Lov-DE showed a 1.83-fold and 1.44-fold higher the area under the curve(AUC0-8 h)of Lov compared with that of the Lov suspension and CD complex in SD rats, respectively.Lov-DE reduced the metabolism of Lov in the small intestine and improved its oral absorption in SD rats.

To examine expression of transforming growth factor-beta 1 (TGF-beta 1) and TGF beta receptor II (T beta R-II) and steroidogenic acute regulatory protein (StAR) in the corpus luteum (CL) of pregnant monkeys at various stages and to study possible effect of IFN-gamma on their production.In situ hybridization and immunohistochemistry were applied to detect mRNA and protein.The expression of StAR, TGF-beta 1, and T beta R-II in the pregnant monkey CL was progressively decreased from d 15 to d 35 of gestation. IFN-gamma down-regulated the expression of TGF-beta 1, T beta R-II, as well as StAR.TGF-beta 1 may play an important role in the CL formation and functional maintaining; IFN-gamma down-regulates the expression of TGF-beta 1, T beta R-II, and StAR.