6-Paradol Acts as a Potential Anti-obesity Vanilloid from Grains of Paradise.

SCOPE: Grains of Paradise (GOP), the seeds of Aframomum melegueta, has anti-obesity effects. However, the mechanisms underlying the effects remain unclear. METHODS AND RESULTS: This study sets up to study the anti-obesity impact and homeostatic effects of 6-paradol, a major vanilloid found in GOP, and investigates the physiological outputs and the lipometabolism-related gene in fat and liver in high-fat-induced obese mice with a comparison with structurally similar vanilloids (6-gingerol and 6-shogaol). The vanilloids are synthesized in adequate quantities for performing animal experiments and orally administered to 6-week-old male mice over 2 weeks. This study found that 6-paradol decreased body weight gain and visceral and subcutaneous fats in 2 weeks, whereas 6-gingerol and 6-shogaol have no effect. Additionally, 6-paradol suppresses the hepatic cholesterol and triglyceride and significantly decreases the gene expression related to fatty acid synthesis, lipid transportation, and adipocyte differentiation in both liver and adipose tissue. Moreover, phosphorylation of AMP-activated protein kinase (AMPK) that greatly contributes to lipometabolism is promoted by 6-gingerol but not 6-paradol. CONCLUSION: These results suggest that 6-paradol regulates several obesity-related genes in an AMPK-independent manner. Therefore, it could be the principal active vanilloid in GOP giving it anti-obesity properties with a different mechanism.

Development of synthetic microRNA-214 showing enhanced cytotoxicity and RNase resistance for treatment of canine hemangiosarcoma.

MicroRNA-214 (miR-214), a pivotal tumour-suppressive miRNA, is downregulated in canine hemangiosarcoma (HSA) cells. Although these tumour-suppressive miRNAs are potential therapeutic agents, their clinical efficacy may be limited because of their vulnerability to RNase-rich microenvironments and low in vivo transfection rates. We developed synthetic miR-214s with enhanced cytotoxicity, RNase resistance and quantity of miR-214 in/on cells. These synthetic miR-214s were synthesized by various chemical modifications (such as 4'-aminoethyl-2'-fluoro, 2'-fluoro, 2'-O-methyl, phosphorothioate and oligospermine modifications) of the wild-type mature miR-214 sequences. Transfection of HSA cells with synthetic miR-214 (miR-214 5AE) demonstrated significant growth suppressive effect and induced the strongest apoptotic response. Synthetic miR-214s (miR-214 5AE, miR-214 10AE and miR-214 OS) were much more stable than mature miR-214s in foetal bovine serum. Similar to mature miR-214, 5AE and OS suppressed the expression level of COP1 in HSA cells. The quantity of synthetic miR-214s in/on cells was higher than that of mature miR-214. In conclusion, we developed a clinically applicable, synthetic miR-214 5AE that regulates the COP1 protein expression similar to that mediated by mature miR-214. Additionally, miR-214 5AE confers better cytotoxicity, nuclease resistance and transfection rate than mature miR-214. Thus, miR-214 5AE could potentially be a novel miRNA-based chemotherapeutic agent that could improve the prognosis of HSA. Its in vivo effects on canine HSA need to be examined in future.

Combined treatment with the phenolics (-)-epigallocatechin-3-gallate and ferulic acid improves cognition and reduces Alzheimer-like pathology in mice.

"Nutraceuticals" are well-tolerated natural dietary compounds with drug-like properties that make them attractive as Alzheimer's disease (AD) therapeutics. Combination therapy for AD has garnered attention following a recent National Institute on Aging mandate, but this approach has not yet been fully validated. In this report, we combined the two most promising nutraceuticals with complementary anti-amyloidogenic properties: the plant-derived phenolics (-)-epigallocatechin-3-gallate (EGCG, an α-secretase activator) and ferulic acid (FA, a ß-secretase modulator). We used transgenic mice expressing mutant human amyloid ß-protein precursor and presenilin 1 (APP/PS1) to model cerebral amyloidosis. At 12 months of age, we orally administered EGCG and/or FA (30 mg/kg each) or vehicle once daily for 3 months. At 15 months, combined EGCG-FA treatment reversed cognitive impairment in most tests of learning and memory, including novel object recognition and maze tasks. Moreover, EGCG- and FA-treated APP/PS1 mice exhibited amelioration of brain parenchymal and cerebral vascular ß-amyloid deposits and decreased abundance of amyloid ß-proteins compared with either EGCG or FA single treatment. Combined treatment elevated nonamyloidogenic soluble APP-α and α-secretase candidate and down-regulated amyloidogenic soluble APP-ß, ß-C-terminal APP fragment, and ß-secretase protein expression, providing evidence for a shift toward nonamyloidogenic APP processing. Additional beneficial co-treatment effects included amelioration of neuroinflammation, oxidative stress, and synaptotoxicity. Our findings offer preclinical evidence that combined treatment with EGCG and FA is a promising AD therapeutic approach.

Superior Efficacy of Lipid Emulsion Infusion Over Serum Alkalinization in Reversing Amitriptyline-Induced Cardiotoxicity in Guinea Pig.

BACKGROUND: Tricyclic antidepressants (TCAs) are a major cause of fatal drug poisoning due to their cardiotoxicity. Alkalinization by sodium bicarbonate (NaHCO3) administration, the first-line therapy for TCA-induced cardiotoxicity, can occasionally yield insufficient efficacy in severe cases. Because most TCAs are highly lipophilic, lipid emulsion may be more effective than alkalinization. However, it remains to be determined whether lipid emulsion is more beneficial than alkalinization in reversing amitriptyline-induced cardiotoxicity. METHODS: Hemodynamic variables were recorded from in vivo guinea pig models and Langendorff-perfused hearts. Whole-cell patch-clamp experiments were conducted on enzymatically isolated ventricular cardiomyocytes to record fast sodium currents (INa). Lipid solutions were prepared using 20% Intralipid. The pH of the alkaline solution was set at 7.55. We assessed the effect of lipid emulsion on reversing amitriptyline-induced cardiotoxicity, in vivo and in vitro, compared to alkalinization. The data were evaluated by Student t test, 1-way repeated-measures analysis of variance, or analysis of covariance (covariate = amitriptyline concentration); we considered data statistically significant when P < .05. RESULTS: In the in vivo model, intervention with lipids significantly reversed the amitriptyline-induced depression of mean arterial pressure and prolongation of QRS duration on electrocardiogram more than alkalinization (mean arterial pressure, mean difference [95% confidence interval]: 19.0 mm Hg [8.5-29.4]; QRS duration, mean difference [95% confidence interval] -12.0 milliseconds [-16.1 to -7.8]). In the Langendorff experiments, perfusion with 1% and 2% lipid solutions demonstrated significant recovery in left ventricular developed pressure (LVdevP), maximum change rate of increase of LVdevP (dP/dtmax) and rate-pressure product compared with alkaline solution (LVdevP [mm Hg], alkaline 57 ± 35, 1% lipid 94 ± 12, 2% lipid 110 ± 14; dP/dtmax [mm Hg/s], alkaline 748 ± 441, 1% lipid 1502 ± 334, 2% lipid 1753 ± 389; rate-pressure product [mm Hg·beats·minute], alkaline 11,214 ± 8272, 1% lipid 19,025 ± 8427, 2% lipid 25,261 ± 4803 with analysis of covariance). Furthermore, lipid solutions (0.5%-4%) resulted in greater recovery of hemodynamic parameters at 3 µM amitriptyline. Amitriptyline inhibited INa in a dose-dependent manner: the half-maximal inhibitory concentration (IC50) was 0.39 µM. The IC50 increased to 0.75 µM in the alkaline solution, 3.2 µM in 1% lipid solution, and 6.1 µM in 2% lipid solution. Furthermore, the lipid solution attenuated the use-dependent block of sodium channels by amitriptyline more than alkaline solution. On 30 consecutive pulses at 1 Hz, the current decreased to 50.1 ± 2.1, 60.3 ± 1.9, and 90.4% ± 1.8% in standard, alkaline, and 1% lipid solution, respectively. Even 0.5% lipid solution showed greater effects than the alkaline solution in all experiments. CONCLUSIONS: Lipid emulsion significantly suppressed amitriptyline-induced INa, inhibition, which was likely related to the marked improvement in hemodynamic status observed in vivo and in isolated perfused hearts. These results suggest the superiority of lipid emulsion as the first-line therapy for TCA-induced cardiotoxicity compared to alkalinization therapy.

Hypersensitivity of BRCA2 deficient cells to rosemary extract explained by weak PARP inhibitory activity.

Rosemary extract is used in food additives and traditional medicine and has been observed to contain anti-tumor activity. In this study, rosemary extract is hypothesized to induce synthetic lethality in BRCA2 deficient cells by PARP inhibition. Chinese hamster lung V79 cells and its mutant cell lines, V-C8 (BRCA2 deficient) and V-C8 with BRCA2 gene correction were used. Rosemary extract and its major constituent chemicals were tested for their cytotoxicity by colony formation assay in cells of different BRCA2 status. The latter chemicals were tested for inhibitory effect of poly (ADP-ribose) polymerase (PARP) activity in vitro and in vivo. Rosemary has shown selective cytotoxicity against V-C8 cells (IC50 17 µg/ml) compared to V79 cells (IC50 26 µg/ml). Among tested chemicals, gallic acid and carnosic acid showed selective cytotoxicity to V-C8 cells along with PARP inhibitory effects. Carnosol showed comparative PARP inhibitory effects at 100 µM compared to carnosic acid and gallic acid, but the selective cytotoxicity was not observed. In conclusion, we predict that within rosemary extract two specific constituent components; gallic acid and carnosic acid were the cause for the synthetic lethality.

Methylene blue modulates ß-secretase, reverses cerebral amyloidosis, and improves cognition in transgenic mice.

Amyloid precursor protein (APP) proteolysis is required for production of amyloid-ß (Aß) peptides that comprise ß-amyloid plaques in the brains of patients with Alzheimer disease (AD). Here, we tested whether the experimental agent methylene blue (MB), used for treatment of methemoglobinemia, might improve AD-like pathology and behavioral deficits. We orally administered MB to the aged transgenic PSAPP mouse model of cerebral amyloidosis and evaluated cognitive function and cerebral amyloid pathology. Beginning at 15 months of age, animals were gavaged with MB (3 mg/kg) or vehicle once daily for 3 months. MB treatment significantly prevented transgene-associated behavioral impairment, including hyperactivity, decreased object recognition, and defective spatial working and reference memory, but it did not alter nontransgenic mouse behavior. Moreover, brain parenchymal and cerebral vascular ß-amyloid deposits as well as levels of various Aß species, including oligomers, were mitigated in MB-treated PSAPP mice. These effects occurred with inhibition of amyloidogenic APP proteolysis. Specifically, ß-carboxyl-terminal APP fragment and ß-site APP cleaving enzyme 1 protein expression and activity were attenuated. Additionally, treatment of Chinese hamster ovary cells overexpressing human wild-type APP with MB significantly decreased Aß production and amyloidogenic APP proteolysis. These results underscore the potential for oral MB treatment against AD-related cerebral amyloidosis by modulating the amyloidogenic pathway.

The effect of lipid emulsion on intracellular bupivacaine as a mechanism of lipid resuscitation: an electrophysiological study using voltage-gated proton channels.

BACKGROUND: Lipid resuscitation has become a standard treatment for local anesthetic (LA) systemic toxicity, but its mechanisms remain to be fully elucidated. Although the partitioning effect is one of the proposed mechanisms, it is difficult to evaluate its impact independently from several other mechanisms or to examine the intracellular concentration of a LA, which is primarily responsible for LA systemic toxicity. We recently reported that LAs as weak bases reduced voltage-gated proton currents by increasing intracellular pH, which could be estimated from the reversal potentials of the channels (Vrev). Using this characteristic, we examined the partitioning effect in detail and showed its impact on lipid resuscitation. METHODS: A whole-cell voltage clamp technique was used to record proton channel currents in a rat microglial cell line (GMI-R1). We used Intralipid® 20% as lipid emulsion. The effects of lipid emulsion on the intracellular concentrations of LAs were evaluated by measuring the current amplitude and the Vrev. The intracellular concentrations of LAs were calculated by the Henderson-Hasselbalch equation, using estimated intracellular pH. To confirm the importance of partitioning, we separated lipid by centrifugation. Data are means ± SD unless otherwise stated. RESULTS: Bupivacaine (1 mM) decreased proton currents to 43% ± 10% of the control and shifted the Vrev to positive voltages (from -88.0 ± 4.1 to -76.0 ± 5.5 mV, n = 5 each, P = 0.02). An addition of the lipid emulsion recovered the currents to 79% ± 2% of the control and returned the Vrev toward the control value (to -86.0 ± 7.1 mV, n = 5, P = 0.03). Both recoveries of the current and Vrev in the centrifuged aqueous extract were almost the same as in the 4% lipid solution (-85.6 ± 4.9 mV, n = 5, P = 0.9, 95% confidence interval for difference = -9.3 to 8.6). When 1 mM bupivacaine was applied extracellularly, the intracellular concentration of the charged form of bupivacaine was estimated to reach about 18.1 ± 3.9 mM but decreased to 5.4 ± 1.8 mM by the 4% lipid solution. CONCLUSIONS: Here we quantitatively evaluated for the first time the partitioning effect of lipid emulsion therapy on the intracellular concentration of bupivacaine in real-time settings by analyzing behaviors of voltage-gated proton channels. Our results suggested that lipid emulsion markedly reduced the intracellular concentration of bupivacaine, which was mostly due to the partitioning effect. This could contribute to our understanding of the mechanisms underlying lipid resuscitation, especially the importance of the partitioning effect.

Octyl gallate markedly promotes anti-amyloidogenic processing of APP through estrogen receptor-mediated ADAM10 activation.

Our previous studies showed that the green tea-derived polyphenolic compound (-)-epigallocatechin-3 gallate (EGCG) reduces amyloid-ß (Aß) production in both neuronal and mouse Alzheimer's disease (AD) models in concert with activation of estrogen receptor-α/phosphatidylinositide 3-kinase/protein kinase B (ERα/PI3K/Akt) signaling and anti-amyloidogenic amyloid precursor protein (APP) α-secretase (a disintegrin and metallopeptidase domain-10, ADAM10) processing. Since the gallate moiety in EGCG may correspond to the 7α position of estrogen, thereby facilitating ER binding, we extensively screened the effect of other gallate containing phenolic compounds on APP anti-amyloidogenic processing. Octyl gallate (OG; 10 µM), drastically decreased Aß generation, in concert with increased APP α-proteolysis, in murine neuron-like cells transfected with human wild-type APP or "Swedish" mutant APP. OG markedly increased production of the neuroprotective amino-terminal APP cleavage product, soluble APP-α (sAPPα). In accord with our previous study, these cleavage events were associated with increased ADAM10 maturation and reduced by blockade of ERα/PI3k/Akt signaling. To validate these findings in vivo, we treated Aß-overproducing Tg2576 mice with OG daily for one week by intracerebroventricular injection and found decreased Aß levels associated with increased sAPPα. These data indicate that OG increases anti-amyloidogenic APP α-secretase processing by activation of ERα/PI3k/Akt signaling and ADAM10, suggesting that this compound may be an effective treatment for AD.

Electromagnetic treatment to old Alzheimer's mice reverses ß-amyloid deposition, modifies cerebral blood flow, and provides selected cognitive benefit.

Few studies have investigated physiologic and cognitive effects of "long-term" electromagnetic field (EMF) exposure in humans or animals. Our recent studies have provided initial insight into the long-term impact of adulthood EMF exposure (GSM, pulsed/modulated, 918 MHz, 0.25-1.05 W/kg) by showing 6+ months of daily EMF treatment protects against or reverses cognitive impairment in Alzheimer's transgenic (Tg) mice, while even having cognitive benefit to normal mice. Mechanistically, EMF-induced cognitive benefits involve suppression of brain ß-amyloid (Aß) aggregation/deposition in Tg mice and brain mitochondrial enhancement in both Tg and normal mice. The present study extends this work by showing that daily EMF treatment given to very old (21-27 month) Tg mice over a 2-month period reverses their very advanced brain Aß aggregation/deposition. These very old Tg mice and their normal littermates together showed an increase in general memory function in the Y-maze task, although not in more complex tasks. Measurement of both body and brain temperature at intervals during the 2-month EMF treatment, as well as in a separate group of Tg mice during a 12-day treatment period, revealed no appreciable increases in brain temperature (and no/slight increases in body temperature) during EMF "ON" periods. Thus, the neuropathologic/cognitive benefits of EMF treatment occur without brain hyperthermia. Finally, regional cerebral blood flow in cerebral cortex was determined to be reduced in both Tg and normal mice after 2 months of EMF treatment, most probably through cerebrovascular constriction induced by freed/disaggregated Aß (Tg mice) and slight body hyperthermia during "ON" periods. These results demonstrate that long-term EMF treatment can provide general cognitive benefit to very old Alzheimer's Tg mice and normal mice, as well as reversal of advanced Aß neuropathology in Tg mice without brain heating. Results further underscore the potential for EMF treatment against AD.

Electromagnetic field treatment protects against and reverses cognitive impairment in Alzheimer's disease mice.

Despite numerous studies, there is no definitive evidence that high-frequency electromagnetic field (EMF) exposure is a risk to human health. To the contrary, this report presents the first evidence that long-term EMF exposure directly associated with cell phone use (918 MHz; 0.25 w/kg) provides cognitive benefits. Both cognitive-protective and cognitive-enhancing effects of EMF exposure were discovered for both normal mice and transgenic mice destined to develop Alzheimer's-like cognitive impairment. The cognitive interference task utilized in this study was designed from, and measure-for-measure analogous to, a human cognitive interference task. In Alzheimer's disease mice, long-term EMF exposure reduced brain amyloid-beta (Abeta) deposition through Abeta anti-aggregation actions and increased brain temperature during exposure periods. Several inter-related mechanisms of EMF action are proposed, including increased Abeta clearance from the brains of Alzheimer's disease mice, increased neuronal activity, and increased cerebral blood flow. Although caution should be taken in extrapolating these mouse studies to humans, we conclude that EMF exposure may represent a non-invasive, non-pharmacologic therapeutic against Alzheimer's disease and an effective memory-enhancing approach in general.

Protection against cognitive deficits and markers of neurodegeneration by long-term oral administration of melatonin in a transgenic model of Alzheimer disease.

The neurohormone melatonin has been reported to exert anti-beta-amyloid aggregation, antioxidant, and anti-inflammatory actions in various in vitro and animal models. To comprehensively determine the potential for long-term melatonin treatment to protect Alzheimer's transgenic mice against cognitive impairment and development of beta-amyloid (Abeta) neuropathology, we administered melatonin (100 mg/L drinking water) to APP + PS1 double transgenic (Tg) mice from 2-2.5 months of age to their killing at age 7.5 months. A comprehensive behavioral battery administered during the final 6 weeks of treatment revealed that Tg mice given melatonin were protected from cognitive impairment in a variety of tasks of working memory, spatial reference learning/memory, and basic mnemonic function; Tg control mice remained impaired in all of these cognitive tasks/domains. Immunoreactive Abeta deposition was significantly reduced in hippocampus (43%) and entorhinal cortex (37%) of melatonin-treated Tg mice. Although soluble and oligomeric forms of Abeta1-40 and 1-42 were unchanged in the hippocampus and cortex of the same melatonin-treated Tg mice, their plasma Abeta levels were elevated. These Abeta results, together with our concurrent demonstration that melatonin suppresses Abeta aggregation in brain homogenates, are consistent with a melatonin-facilitated removal of Abeta from the brain. Inflammatory cytokines such as tumor necrosis factor (TNF)-alpha were decreased in hippocampus (but not plasma) of Tg+ melatonin mice. Finally, the cortical mRNA expression of three antioxidant enzymes (SOD-1, glutathione peroxidase, and catalase) was significantly reduced to non-Tg levels by long-term melatonin treatment in Tg mice. Thus, melatonin's cognitive benefits could involve its anti-Abeta aggregation, anti-inflammatory, and/or antioxidant properties. Our findings provide support for long-term melatonin therapy as a primary or complementary strategy for abating the progression of Alzheimer disease.

ADAM10 activation is required for green tea (-)-epigallocatechin-3-gallate-induced alpha-secretase cleavage of amyloid precursor protein.

Recently, we have shown that green tea polyphenol (-)-epigallocatechin-3-gallate (EGCG) exerts a beneficial role on reducing brain Abeta levels, resulting in mitigation of cerebral amyloidosis in a mouse model of Alzheimer disease. EGCG seems to accomplish this by modulating amyloid precursor protein (APP) processing, resulting in enhanced cleavage of the alpha-COOH-terminal fragment (alpha-CTF) of APP and corresponding elevation of the NH(2)-terminal APP product, soluble APP-alpha (sAPP-alpha). These beneficial effects were associated with increased alpha-secretase cleavage activity, but no significant alteration in beta-or gamma-secretase activities. To gain insight into the molecular mechanism whereby EGCG modulates APP processing, we evaluated the involvement of three candidate alpha-secretase enzymes, a-disintegrin and metalloprotease (ADAM) 9, 10, or 17, in EGCG-induced non-amyloidogenic APP metabolism. Results show that EGCG treatment of N2a cells stably transfected with "Swedish" mutant human APP (SweAPP N2a cells) leads to markedly elevated active ( approximately 60 kDa mature form) ADAM10 protein. Elevation of active ADAM10 correlates with increased alpha-CTF cleavage, and elevated sAPP-alpha. To specifically test the contribution of ADAM10 to non-amyloidogenic APP metabolism, small interfering RNA knockdown of ADAM9, -10, or -17 mRNA was employed. Results show that ADAM10 (but not ADAM9 or -17) is critical for EGCG-mediated alpha-secretase cleavage activity. In summary, ADAM10 activation is necessary for EGCG promotion of non-amyloidogenic (alpha-secretase cleavage) APP processing. Thus, ADAM10 represents an important pharmacotherapeutic target for the treatment of cerebral amyloidosis in Alzheimer disease.

Green tea epigallocatechin-3-gallate (EGCG) modulates amyloid precursor protein cleavage and reduces cerebral amyloidosis in Alzheimer transgenic mice.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder pathologically characterized by deposition of beta-amyloid (Abeta) peptides as senile plaques in the brain. Recent studies suggest that green tea flavonoids may be used for the prevention and treatment of a variety of neurodegenerative diseases. Here, we report that (-)-epigallocatechin-3-gallate (EGCG), the main polyphenolic constituent of green tea, reduces Abeta generation in both murine neuron-like cells (N2a) transfected with the human "Swedish" mutant amyloid precursor protein (APP) and in primary neurons derived from Swedish mutant APP-overexpressing mice (Tg APPsw line 2576). In concert with these observations, we find that EGCG markedly promotes cleavage of the alpha-C-terminal fragment of APP and elevates the N-terminal APP cleavage product, soluble APP-alpha. These cleavage events are associated with elevated alpha-secretase activity and enhanced hydrolysis of tumor necrosis factor alpha-converting enzyme, a primary candidate alpha-secretase. As a validation of these findings in vivo, we treated Tg APPsw transgenic mice overproducing Abeta with EGCG and found decreased Abeta levels and plaques associated with promotion of the nonamyloidogenic alpha-secretase proteolytic pathway. These data raise the possibility that EGCG dietary supplementation may provide effective prophylaxis for AD.