Raspberry ketone promotes FNDC5 protein expression via HO-1 upregulation in 3T3-L1 adipocytes.

Obesity is a global health problem and a risk factor for cardiovascular diseases and cancers. Exercise is an effective intervention to combat obesity. Fibronectin type III domain containing protein 5 (FNDC5)/irisin, a myokine, can stimulate the browning of white adipose tissue by increasing uncoupling protein 1 (UCP1) expression, and therefore may represent a link between the beneficial effects of exercise and improvement in metabolic diseases. Thus, upregulating the endogenous expression of FNDC5/irisin by administering medication would be a good approach for treating obesity. Herein, we evaluated the efficacy of raspberry ketone (RK) in inducing FNDC5/irisin expression and the underlying mechanisms. The expression of brown fat-specific proteins (PR domain containing 16 (PRDM16), CD137, and UCP1), heme oxygenase-1 (HO-1), FNDC5, and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) in differentiated 3T3-L1 adipocyte was analyzed by western blotting or immunofluorescence. The level of irisin in the culture medium was also assayed using an enzyme-linked immunosorbent assay kit. Results showed that RK (50 µM) significantly induced the upregulation of FNDC5 protein in differentiated 3T3-L1 adipocytes; however, the irisin level in the culture media was unaffected. Moreover, RK significantly increased the levels of PGC1α, brown adipocyte markers (PRDM16, CD137, and UCP1), and HO-1. Furthermore, the upregulation of PGC1α and FNDC5 and the browning effect induced by RK were significantly reduced by SnPP or FNDC5 siRNA, respectively. In conclusion, RK can induce FNDC5 protein expression via the HO-1 signaling pathway, and this study provides new evidence for the potential use of RK in the treatment of obesity.

YC-1 alleviates bone loss in ovariectomized rats by inhibiting bone resorption and inducing extrinsic apoptosis in osteoclasts.

Osteoporosis is a major health problem in postmenopausal women and the elderly that leads to fractures associated with substantial morbidity and mortality. Current osteoporosis therapies have significant drawbacks, and the risk of fragility fractures has not yet been eliminated. There remains an unmet need for a broader range of therapeutics. Previous studies have shown that YC-1 has important regulatory functions in the cardiovascular and nervous systems. Many of the YC-1 effector molecules in platelets, smooth muscle cells and neurons, such as cGMP and µ-calpain, also have important functions in osteoclasts. In this study, we explored the effects of YC-1 on bone remodeling and determined the potential of YC-1 as a treatment for postmenopausal osteoporosis. Micro-computed tomography of lumbar vertebrae showed that YC-1 significantly improved trabecular bone microarchitecture in ovariectomized rats compared with sham-operated rats. YC-1 also significantly reversed the increases in serum bone resorption and formation in these rats, as measured by enzyme immunoassays for serum CTX-1 and P1NP, respectively. Actin ring and pit formation assays and TRAP staining analysis showed that YC-1 inhibited osteoclast activity and survival. YC-1 induced extrinsic apoptosis in osteoclasts by activating caspase-3 and caspase-8. In osteoclasts, YC-1 stimulated µ-calpain activity and inhibited Src activity. Our findings provide proof-of-concept for YC-1 as a novel antiresorptive treatment strategy for postmenopausal osteoporosis, confirming an important role of nitric oxide/cGMP/protein kinase G signaling in bone.

Genistein suppresses leptin-induced proliferation and migration of vascular smooth muscle cells and neointima formation.

Obesity is a strong risk factor for the development of cardiovascular diseases and is associated with a marked increase in circulating leptin concentration. Leptin is a peptide hormone mainly produced by adipose tissue and is regulated by energy level, hormones and various inflammatory mediators. Genistein is an isoflavone that exhibits diverse health-promoting effects. Here, we investigated whether genistein suppressed the atherogenic effect induced by leptin. The A10 cells were treated with leptin and/or genistein, and then the cell proliferation and migration were analysed. The reactive oxygen species (ROS) and proteins levels were also measured, such as p44/42MAPK, cell cycle-related protein (cyclin D1 and p21) and matrix metalloproteinase-2 (MMP-2). Immunohistochemistry and morphometric analysis were used for the neointima formation in a rat carotid artery injury model. Genistein (5 µM) significantly inhibited both the proliferation and migration of leptin (10 ng/ml)-stimulated A10 cells. In accordance with these finding, genistein decreased the leptin-stimulated ROS production and phosphorylation of the p44/42MAPK signal transduction pathway. Meanwhile, genistein reversed the leptin-induced expression of cyclin D1, and cyclin-dependent kinase inhibitor, p21. Genistein attenuated leptin-induced A10 cell migration by inhibiting MMP-2 activity. Furthermore, the leptin (0.25 mg/kg)-augmented neointima formation in a rat carotid artery injury model was attenuated in the genistein (5 mg/kg body weight)-treated group when compared with the balloon injury plus leptin group. Genistein was capable of suppressing the atherogenic effects of leptin in vitro and in vivo, and may be a promising candidate drug in the clinical setting.

Heat shock protein 70 and AMP-activated protein kinase contribute to 17-DMAG-dependent protection against heat stroke.

Heat shock protein 70 (Hsp70) preconditioning induces thermotolerance, and adenosine monophosphate (AMP)-activated protein kinase (AMPK) plays a role in the process of autophagy. Here, we investigated whether 17-dimethylaminoethylamino-17-demethoxy-geldanamycin (17-DMAG) protected against heat stroke (HS) in rats by up-regulation of Hsp70 and phosphorylated AMPK (pAMPK). To produce HS, male Sprague-Dawley rats were placed in a chamber with an ambient temperature of 42°C. Physiological function (mean arterial pressure, heart rate and core temperature), hepatic and intestinal injury, inflammatory mediators and levels of Hsp70, pAMPK and light chain 3 (LC3B) in hepatic tissue were measured in HS rats or/and rats pre-treated with 17-DMAG. 17-DMAG pre-treatment significantly attenuated hypotension and organ dysfunction induced by HS in rats. The survival time during HS was also prolonged by 17-DMAG treatment. Hsp70 expression was increased, whereas pAMPK levels in the liver were significantly decreased in HS rats. Following pre-treatment with 17-DMAG, Hsp70 protein levels increased further, and pAMPK levels were enhanced. Treatment with an AMPK activator significantly increased the LC3BII/LC3BI ratio as a marker of autophagy in HS rats. Treatment with quercetin significantly suppressed Hsp70 and pAMPK levels and reduced the protective effects of 17-DMAG in HS rats. Both of Hsp70 and AMPK are involved in the 17-DMAG-mediated protection against HS. 17-DMAG may be a promising candidate drug in the clinical setting.

α-Lipoic acid enhances endogenous peroxisome-proliferator-activated receptor-γ to ameliorate experimental autoimmune encephalomyelitis in mice.

ALA (α-lipoic acid) is a natural, endogenous antioxidant that acts as a PPAR-γ (peroxisome-proliferator-activated receptor-γ) agonist to counteract oxidative stress. Thus far, the antioxidative and immunomodulatory effects of ALA on EAE (experimental autoimmune encephalomyelitis) are not well understood. In this study, we found that ALA restricts the infiltration of inflammatory cells into the CNS (central nervous system) in MOG (myelin oligodendrocyte glycoprotein)-EAE mice, thus reducing the disease severity. In addition, we revealed that ALA significantly suppresses the number and percentage of encephalitogenic Th1 and Th17 cells and increases splenic Treg-cells (regulatory T-cells). Strikingly, we further demonstrated that ALA induces endogenous PPAR-γ centrally and peripherally but has no effect on HO-1 (haem oxygenase 1). Together, these data suggest that ALA can up-regulate endogenous systemic and central PPAR-γ and enhance systemic Treg-cells to inhibit the inflammatory response and ameliorate MOG-EAE. In conclusion, our data provide the first evidence that ALA can augment the production of PPAR-γ in vivo and modulate adaptive immunity both centrally and peripherally in EAE and may reveal further antioxidative and immunomodulatory mechanisms for the application of ALA in human MS (multiple sclerosis).

Ethyl pyruvate reduces acute lung injury via regulation of iNOS and HO-1 expression in endotoxemic rats.

BACKGROUND: Ethyl pyruvate (EP) has been shown to attenuate lipopolysaccharide (LPS)-induced acute lung injury (ALI). Induction of heme oxygenase-1 (HO-1) and suppression of inducible nitric oxide synthase (iNOS) expression provide cytoprotection in lung and vascular injury. The aim of this study is to evaluate whether the beneficial effect of EP on lung inflammation is related to HO-1 induction in a rat model of LPS-induced ALI. MATERIALS AND METHODS: Rats were administered LPS (30 mg/kg) by intravenous infusion for 4 h to induce ALI. EP (20, 40, and 60 mg/kg/4 h i.v. infusion) or vehicle was given 1 h after LPS initiation. RESULTS: EP 40 and 60 mg/kg attenuated plasma levels of TNF-α and IL-6 caused by LPS, and further increased IL-10 levels compared with the LPS group. At 6 h after LPS initiation, iNOS protein expression in lungs and plasma NO metabolite levels were markedly increased, which were reduced by EP 60 mg/kg. LPS caused a significant HO-1 induction, whereas administration of EP 60 mg/kg significantly induced higher HO-1 expression compared with the LPS group. The beneficial effects of EP on cytokines and iNOS expression were reversed by HO-1 inhibitor SnPP. EP significantly suppressed phosphorylated p38 MAPK and increased phosphorylated ERK1/2 protein levels in the lung tissue. The edema and infiltration of neutrophils into lungs was reduced by EP. CONCLUSION: EP reduced LPS-induced ALI, which may be mediated by induction of HO-1. The underlying mechanisms are associated with suppression of p38 MAPK and increase of ERK1/2 signaling pathway activation.

Hyperbaric oxygen suppressed tumor progression through the improvement of tumor hypoxia and induction of tumor apoptosis in A549-cell-transferred lung cancer.

Tumor cells have long been recognized as a relative contraindication to hyperbaric oxygen treatment (HBOT) since HBOT might enhance progressive cancer growth. However, in an oxygen deficit condition, tumor cells are more progressive and can be metastatic. HBOT increasing in oxygen partial pressure may benefit tumor suppression. In this study, we investigated the effects of HBOT on solid tumors, such as lung cancer. Non-small cell human lung carcinoma A549-cell-transferred severe combined immunodeficiency mice (SCID) mice were selected as an in vivo model to detect the potential mechanism of HBOT in lung tumors. HBOT not only improved tumor hypoxia but also suppressed tumor growth in murine xenograft tumor models. Platelet endothelial cell adhesion molecule (PECAM-1/CD31) was significantly increased after HBOT. Immunostaining of cleaved caspase-3 was demonstrated and apoptotic tumor cells with nuclear debris were aggregated starting on the 14th-day after HBOT. In vitro, HBOT suppressed the growth of A549 cells in a time-dependent manner and immediately downregulated the expression of p53 protein after HBOT in A549 cells. Furthermore, HBOT-reduced p53 protein could be rescued by a proteasome degradation inhibitor, but not an autophagy inhibitor in A549 cells. Our results demonstrated that HBOT improved tissue angiogenesis, tumor hypoxia and increased tumor apoptosis to lung cancer cells in murine xenograft tumor models, through modifying the tumor hypoxic microenvironment. HBOT will merit further cancer therapy as an adjuvant treatment for solid tumors, such as lung cancer.

Involvement of the p62/Nrf2/HO-1 pathway in the browning effect of irisin in 3T3-L1 adipocytes.

Irisin has gained attention because of its potential applications in the treatment of metabolic diseases. Accumulating evidence indicates that irisin attenuates obesity via the browning of white adipose tissue; however, the underlying mechanisms are unclear. Here, we evaluated the effects of irisin on adipocyte browning and the underlying mechanisms. The western blotting and immunofluorescence analyses demonstrated that irisin significantly induced the up-regulation of brown fat-specific proteins (PGC1α, PRDM16, and UCP-1) and HO-1 in 3T3-L1 adipocytes. Moreover, irisin significantly increased the levels of cytosolic p62 and nuclear Nrf2. These effects of irisin in the adipocytes were attenuated by treatment with SnPP or p62 siRNA. In addition, the browning effect of irisin was observed in BAT-WT-1 cells. These findings suggest that irisin induced browning effect via the p62/Nrf2/HO-1 signalling pathway and that it may be a potential candidate for preventing or treating obesity.

Adenosine modulates cardiovascular functions through activation of extracellular signal-regulated kinases 1 and 2 and endothelial nitric oxide synthase in the nucleus tractus solitarii of rats.

BACKGROUND: The nucleus tractus solitarius (NTS) is the primary integrative center for baroreflex. Adenosine has been shown to play an important modulatory role in blood pressure control in the NTS. Our previous results demonstrated that adenosine decreases blood pressure, heart rate, and renal sympathetic nerve activity and modulates baroreflex responses in the NTS. We also demonstrated that a nitric oxide synthase (NOS) inhibitor may block the cardiovascular effects of adenosine in the NTS, which suggests interaction between the adenosine receptor and NOS. However, the signaling mechanisms of adenosine that induce nitric oxide release in the NTS remain uncertain. The aim of the present study was to investigate the possible signal pathways involved in the cardiovascular regulation of adenosine in the NTS. METHODS AND RESULTS: Adenosine was microinjected into the NTS of urethane-anesthetized male Sprague-Dawley rats. Blood pressure and heart rate decreased significantly after microinjection. The cardiovascular effects of adenosine were attenuated by prior administration of the mitogen-activated protein kinase/extracellular signal-regulated kinase inhibitor PD98059 (6 nmol/60 nL) or an endothelial NOS-selective inhibitor, L-NIO (6 nmol/60 nL); however, the neuronal NOS-specific inhibitor vinyl-L-NIO (600 pmol/60 nL) did not attenuate the cardiovascular effects of adenosine. Western blot and immunohistochemistry studies demonstrated that adenosine induced extracellular signal-regulated kinases 1 and 2 and endothelial NOS phosphorylation in the NTS. Pretreatment with PD98059 diminished the endothelial NOS phosphorylation evoked by adenosine. CONCLUSIONS: These results represent a novel finding that extracellular signal-regulated kinases 1 and 2 is involved in cardiovascular regulation in the NTS. They also indicate that the cardiovascular modulatory effects of adenosine in the NTS are accomplished by activation of mitogen-activated protein kinase/extracellular signal-regulated kinases 1 and 2 and then endothelial NOS.

17-DMAG, an Hsp90 inhibitor, ameliorates ovariectomy-induced obesity in rats.

AIMS: Obesity is not only associated with metabolic diseases but is also a symptom of menopause in women. To date, there are no effective drugs for the management of obesity, and it is important to find new agents with fewer side effects, for the treatment of obesity. This study aimed to determine the anti-obesity effect of 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG), a heat shock protein 90 (Hsp90) inhibitor, and its underlying mechanism in rats with ovariectomy-induced obesity. MAIN METHODS: Ovariectomy (Ovx) rats were treated with 17-DMAG (1 mg kg-1, intraperitoneally) for eight weeks from one week after surgery. The body weight, food intake, locomotor activity, adipogenic- and autophagy-related protein expression in white adipose tissue (WAT) and plasma triglyceride (TG) levels were measured in sham and Ovx rats. KEY FINDINGS: Compared with sham rats, Ovx rats showed increased weight gain, food intake, WAT mass, TG levels, adipogenic protein expression, and decreased locomotor activity. Furthermore, autophagy-related proteins and Foxo3a of WAT were significantly increased in Ovx rats. However, with the exclusion of increased food intake, the changes induced by Ovx were all reversed in 17-DMAG-treated Ovx rats. In addition, the expression of Hsp70 and phosphorylation of Akt increased in 17-DMAG-treated Ovx rats. SIGNIFICANCE: These results suggest that 17-DMAG significantly ameliorated obesity induced by Ovx, and this phenomenon is accompanied by the downregulation of adipogenic-related and autophagy-related proteins as well as the upregulation of Akt-phosphorylation and Hsp70 expression. Therefore, 17-DMAG may be a potential agent for preventing or treating obesity in postmenopausal women.

Effects of haloperidol and risperidone on cerebrohemodynamics in drug-naive schizophrenic patients.

BACKGROUND: Use of antipsychotics may be associated with cerebrovascular adverse events in psychotic patients. In this study, the effects of haloperidol and risperidone on the cerebral hemodynamics and the possible relationships between antipsychotics and cerebrovascular risks tendency were evaluated by Transcranial Doppler ultrasonography (TCD). METHODS: Twenty drug-nai ve schizophrenic patients and 20 normal control subjects were included. The patients were divided into haloperidol- and risperidone-treated groups and received treatment for 8 weeks double-blindly. The subjects' cerebral blood flow mean velocities (MV) and pulsatility index (PI) were measured weekly by TCD. The Positive and Negative Syndrome Scale for schizophrenia (PANSS) was used to assess the patients' psychopathological symptoms. RESULTS: Increased MV and decreased PI were found significantly in drug-nai ve schizophrenic patients than normal subjects before treatment (p<0.01). The decreased PI could be normalized after 8 weeks of antipsychotic treatment, while the increased MV could not. Treatment with haloperidol could significantly increase the PI than the treatment with risperidone (p<0.01) throughout the treatment course. The PANSS scores of both groups were significantly improved (p<0.05) at the endpoints of treatment. CONCLUSIONS: Our findings indicate that haloperidol may affect the cerebral hemodynamics in drug-naive schizophrenics more prominently than that of risperidone via TCD monitoring.

BK-induced COX-2 expression via PKC-delta-dependent activation of p42/p44 MAPK and NF-kappaB in astrocytes.

Bradykinin (BK) is an inflammatory mediator, elevated levels in the region of several brain injury and inflammatory diseases. It has been shown to induce cyclooxygenase-2 (COX-2) expression implicating in inflammatory responses in various cell types. However, the signaling mechanisms underlying BK-induced COX-2 expression in astrocytes remain unclear. First, RT-PCR and Western blotting analysis showed that BK induced the expression of COX-2 mRNA and protein, which was inhibited by B(2) BK receptor antagonist Hoe140, suggesting the involvement of B(2) BK receptors. BK-induced COX-2 expression and translocation of PKC-delta from cytosol to membrane fraction were inhibited by rottlerin, suggesting that PKC-delta might be involved in these responses. This hypothesis was further supported by the transfection with a dominant negative plasmid of PKC-delta significantly blocked BK-induced COX-2 expression. BK-stimulated p42/p44 MAPK phosphorylation, COX-2 mRNA expression, and prostaglandin E(2) (PGE(2)) release were attenuated by PD98059, indicating the involvement of MEK/p42/p44 MAPK in this pathway. Accordingly, BK-stimulated phosphorylation of p42/p44 MAPK was attenuated by rottlerin, indicating that PKC-delta might be an upstream component of p42/p44 MAPK. Moreover, BK-induced COX-2 expression might be mediated through the translocation of NF-kappaB into nucleus which was blocked by helenalin, rottlerin and PD98059, implying the involvement of NF-kappaB. These results suggest that in RBA-1 cells, BK-induced COX-2 expression and PGE(2) release was sequentially mediated through PKC-delta-dependent activation of p42/p44 MAPK and NF-kappaB. Understanding the regulation of COX-2 expression and PGE(2) release induced by BK in astrocytes might provide a new therapeutic strategy of brain injury and inflammatory diseases.

Anti-inflammatory effects of LK-3, on LPS-induced sepsis in rats.

Dextromethorphan (DM), an antitussive agent, has been shown to have anti-inflammatory and immunomodulatory effects in vitro. Thus, the aim of this study was to evaluate the effects of LK-3, an analog of DM, on sepsis induced by intravenous (i.v.) administration of lipopolysaccharide (LPS; 10 mg/ kg) in anesthetized Wistar rats. Results demonstrated that post-treatment with LK-3 (4 mg/kg, i.v.) significantly attenuated the deleterious hemodynamic changes (e.g., hypotension and bradycardia) in rats treated with LPS. Meanwhile, LK-3 (4 mg/kg) significantly inhibited the elevation of plasma tumor necrosis factor-alpha, as well as values of glutamate-oxalacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT) caused by LPS. The induction of inducible NO synthase and the overproduction of NO and superoxide anions by LPS were also reduced by post-treatment of LK-3. Moreover, infiltration of neutrophils into the lungs and liver of rats 8 h after treatment with LPS was also reduced by post-treatment with LK-3. In conclusion, the beneficial effects of LK-3 on LPS-induced sepsis resulted from its anti-inflammatory and antioxidant effects.

Protective effect of baicalein against endotoxic shock in rats in vivo and in vitro.

Dried roots of Scutellaria baicalensis Georgi (Huang qin) are widely used in traditional Chinese medicine. Baicalein is a major bioactive flavonoid component of H. qin that shows a wide range of biological activities, including antioxidant and anti-inflammatory actions. We evaluated therapeutic effects and possible mechanisms of action of baicalein on circulatory failure and vascular dysfunction during sepsis induced by lipopolysaccharide (LPS; 10 mg/kg, i.v.) in anesthetized rats. Treatment of the rats with baicalein (20 mg/kg, i.v.) significantly attenuated the deleterious hemodynamic changes of hypotension and tachycardia caused by LPS and significantly inhibited the elevation of plasma tumor necrosis factor alpha (TNF-alpha). Baicalein also decreased levels of inducible nitric oxide synthase (iNOS) and the overproduction of NO and superoxide anions caused by LPS. It also increased the survival rate of ICR mice (25-30 g) challenged by LPS (60 mg/kg). Moreover, infiltration of neutrophils into the liver and lungs of rats 6h after treatment with LPS was also reduced by baicalein. To investigate the mechanism of action of baicalein on sepsis, RAW 264.7 cells were used as a model. Baicalein inhibited iNOS protein production, and suppressed LPS-induced degradation of IkappaBalpha, the formation of a nuclear factor kappa B (NF-kappaB)-DNA complex and NF-kappaB-dependent reporter gene expression. Thus, the therapeutic effects of baicalein were associated with reductions in TNF-alpha and superoxide anion levels during sepsis. The inhibitory effects of baicalein on iNOS production may be mediated by inhibition of the activation of NF-kappaB. Baicalein may thus prove a potential agent against endotoxemia.

The involvement of AMP-activated protein kinases in the anti-inflammatory effect of nicotine in vivo and in vitro.

AMP-activated protein kinase (AMPK) is the downstream component of a kinase cascade that plays a pivotal role in energy homeostasis. AMPK has recently emerged as an attractive and novel target for inflammatory disorders. Thus, the aim of this study was to assess the role of AMPKalpha in the anti-inflammatory effect of nicotine in carrageenan-induced rat paw edema model and to evaluate the mechanism of nicotine-induced AMPKalpha phosphorylation in RAW 264.7 cells. The results indicate that nicotine alleviated paw edema and the activation of AMPKalpha involved in the anti-inflammatory effect of nicotine in vivo. In addition, nicotine was able to activate AMPKalpha phosphorylation in macrophages and this effect was mediated through nicotinic acetylcholine receptors. Furthermore, nicotine significantly induced the phosphorylation of Akt and the Ca(2+)/calmodulin-dependent protein kinase kinase (CaMKK) protein expression in macrophages. Wortmannin, a specific inhibitor of phosphotidylinositol 3-kinase (PI3K), suppressed nicotine-induced Akt and AMPKalpha phosphorylation. STO-609, a CaMKK inhibitor, not only inhibited the activation of AMPKalpha but also suppressed the phosphorylation of Akt induced by nicotine. In conclusion, both of CaMKK and PI3K/Akt pathways are involved in the nicotine-induced AMPKalpha phosphorylation in macrophages, and the interaction of CaMKK and Akt may exist. AMPKalpha is a novel and critical component of anti-inflammatory effect of nicotine.

Effects of antipsychotics on cognitive performance in drug-naive schizophrenic patients.

It has been reported that antipsychotics may improve cognitive function in the treatment of schizophrenia. The present study examined the effect of haloperidol and risperidone on cognitive performance in schizophrenic patients. 95 healthy subjects and 68 schizophrenic patients were recruited for comparison of cognitive function. As 20 of the 68 schizophrenic patients were drug-naive, they were randomly divided into two groups and double-blinded for treatment with either haloperidol or risperidone for an 8-week period. Each subject received Wisconsin Card Sorting Test (WCST) and Maze paradigms for cognitive function performance. For schizophrenic patients, the Positive and Negative Syndrome Scale (PANSS) was used for evaluation of clinical symptoms. Results demonstrated that in both WCST and Maze paradigms the 68 schizophrenic patients had worse cognitive performance compared with healthy subjects. Of the 20 drug-naive schizophrenic patients from the 68 in-patients, both haloperidol and risperidone improved the clinical symptoms. Maze tasks performance was improved progressively after haloperidol and risperidone treatment, although improvement was greatest with risperidone. Both haloperidol and risperidone had no evident effect on WCST performance. Our findings suggest that Maze paradigms may be an ideal tool for evaluation of pharmacological treatment effects on cognitive function in schizophrenic patients. Furthermore, risperidone may have more treatment benefits than haloperidol on cognitive performance in drug-naive schizophrenic patients.

Heme oxygenase-1 mediates anti-adipogenesis effect of raspberry ketone in 3T3-L1 cells.

BACKGROUND: Obesity is caused by excessive accumulation of body fat and is closely related to complex metabolic diseases. Raspberry ketone (RK), a major aromatic compound in red raspberry, was recently reported to possess anti-obesity effects. However, its mechanisms are unclear. AIM: Adipogenesis plays a critical role in obesity and, therefore, this study aimed to investigate the effect and mechanisms of action of RK on adipogenesis in 3T3-L1 preadipocytes. MATERIALS AND METHODS: 3T3-L1 preadipocytes were differentiated in medium containing insulin, dexamethasone, and 1-methyl-3-isobutylxanthine. Adipocyte lipid contents were determined using oil-red O staining while adipogenic transcription factor and lipogenic protein expressions were determined using western blotting. RESULTS: RK (300-400µM) strongly inhibited lipid accumulation during 3T3-L1 preadipocyte differentiation into adipocytes. RK reduced the CCAAT/enhancer-binding protein-α (C/EBP-α), peroxisome proliferation-activated receptor-γ (PPAR-γ), fatty acid synthase (FAS), and fatty acid-binding protein 4 (FABP4) expressions and increased heme oxygenase-1 (HO-1), Wnt10b, and ß-catenin expressions in 3T3-L1 adipocytes. Additionally, RK inhibited lipid accumulation, and adipogenic transcription factor and lipogenic protein expressions were all decreased by inhibiting HO-1 or ß-catenin using tin protoporphyrin (SnPP) or ß-catenin short-interfering RNA (siRNA), respectively. Furthermore, Wnt10b and ß-catenin expressions were negatively regulation by SnPP. CONCLUSION: RK may exert anti-adipogenic effects through modulation of the HO-1/Wnt/beta-catenin signaling pathway.

Heme oxygenase-1 contributes to the cytoprotection of alpha-lipoic acid via activation of p44/42 mitogen-activated protein kinase in vascular smooth muscle cells.

Alpha-lipoic acid (ALA) is a natural antioxidant that scavenges reactive oxygen species (ROS) and regenerates or recycles endogenous antioxidants. ALA has recently been reported to protect against oxidative injury in various disease processes. The aim of this study was to investigate whether the antioxidant effect of ALA is mediated by the induction of heme oxygenase (HO)-1 in rat aortic smooth muscle cells (A10 cells). ALA significantly induced HO-1 expression accompanied by an increase in HO activity in A10 cells. Pretreatment with ALA increased the resistance of A10 cells to hydrogen-peroxide-induced oxidant stress. This protection of ALA was abrogated in the presence of the HO inhibitor zinc protoporphyrin IX. ALA significantly increased ROS, and this effect was blocked by N-acetyl-cysteine, which also inhibited ALA-induced activation of p44/42 mitogen-activated protein kinase (MAPK) and AP-1, HO-1 expression, and HO activity. These results suggest that ALA induces HO-1 expression through the production of ROS and subsequent activation of the p44/42 MAPK pathway and AP-1 in vascular smooth muscle cells. This study demonstrated that ALA increases the expression of HO-1, a critical cytoprotective molecule, and identified a novel pleiotropic effect of ALA on cardiovascular protection.

Estrogen therapy replenishes vascular tetrahydrobiopterin and reduces oxidative stress in ovariectomized rats.

OBJECTIVE: We investigated whether the effect of estrogen therapy on vascular endothelial function is mediated through increasing the bioavailability of tetrahydrobiopterin (BH4) and associated antioxidant capacity in ovariectomized (Ovx) rats. DESIGN: Aortas of sham-operated, Ovx, and Ovx plus estrogen therapy (Ovx + ET) female Sprague-Dawley rats were used to measure vascular reactivity. Plasma levels of nitric oxide (NO) metabolites, total antioxidant capacity, aortic superoxide anion (O2.), and BH4 contents were determined. RESULTS: Vascular reactivity, assessed on isolated aortic segments, indicated that phenylephrine-induced contraction in the Ovx group was significantly greater than that in the sham and Ovx + ET groups. The vasodilator responses to acetylcholine (10 to 10 M) and L-arginine (L-Arg; 10 M) in the sham and Ovx + ET groups were significantly greater than those in the Ovx group. Pretreatment with BH4 (10 M) enhanced the vasodilator responses to L-Arg in the Ovx group compared with the untreated Ovx group. An inhibitor of BH4 synthesis, 2,4-diamino-6-hydroxypyrimidine (2 mM), significantly attenuated the vasodilator response to L-Arg in the sham and Ovx + ET groups. In addition, Ovx significantly increased O2. production in aortic tissues and decreased plasma NO metabolites levels, whereas ET significantly prevented these effects. Pretreatment with BH4 also significantly decreased aortic O2. production in the Ovx group; both plasma total antioxidant capacity and aortic BH4 contents in the Ovx group decreased significantly compared with those in the sham group, which were also improved by ET. There were no significant differences in the protein expression of endothelial NO synthase in aortas in these groups. CONCLUSIONS: ET increases the availability of vascular BH4 to attenuate O2. production and restores total antioxidant capacity, leading to improved NO-mediated vasodilation in Ovx rats.

Study of hepatotoxicity of naltrexone in the treatment of alcoholism.

Since a black box warning was issued by the Food and Drug Administration regarding the use of the opiate antagonist naltrexone (NTX), many clinicians have been concerned about current labeling of the potential hepatotoxicity risk of NTX in the treatment of opiate dependence and alcoholism. Despite many reports that demonstrated that the use of NTX did not cause elevation of liver enzymes, controversy concerning whether NTX is hepatotoxic continues. The current study monitored 74 alcoholic patients who received 25mg of NTX daily in the first week and then 50mg of NTX daily for the rest of the 12-week period. After the 12-week treatment, levels of the hepatic enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST) did not show any elevation, except in one subject, and the results strongly support that NTX did not induce abnormalities in liver function tests or elevate the liver enzymes. Instead, a statistical significance of decreasing levels of ALT and AST in the liver was shown throughout the study. These findings provide further support that NTX is not hepatotoxic at the recommended daily dose and may be beneficial for patients with elevated liver enzymes.