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Preliminary studies have shown that a lithogenic diet (LG), which contains cholesterol and cholic acid, induces gallstones and hepatic lipid accumulation (HLA), and reduction of blood triglyceride in mice. We hypothesized that an LG induces HLA by diminishing hepatic triglyceride excretion; however, there is no clear understanding of the mechanism of LG-induced HLA. This study aimed to investigate transcript expression related to the synthesis, expenditure, and efflux of hepatic triglyceride, in mice fed an LG for 4 weeks. Results showed lower plasma concentrations of triglyceride in the LG group than in the control group, but no symptoms of hepatic injury were observed. Hepatic mRNA expressions of patatin-like phospholipase domain containing 3 (Pnpla3), microsomal triglyceride transfer protein (Mttp), and acyl-CoA oxidase 1 (Acox1) were also reduced in the LG group. Deoxycholic acid and lithocholic acid promoted intracellular lipid accumulation, reduced triglyceride concentration in media, and suppressed expression of PNPLA3 and MTTP in HepG2 human hepatoma cells. These findings suggest that deoxycholic acid and lithocholic acid promote HLA by inhibiting the expression of PNPLA3, ACOX1, and MTTP that are involved in lipid metabolism.

The lycopene content of tomatoes is important because of its effects on vital physiological functions such as improvement of glucose tolerance and non-alcoholic fatty liver disease. To investigate the influence of the lycopene content of tomatoes on glucose tolerance and hepatic lipid content, homogenates of lycopene-rich (LR) or lycopene-free negative control (NC) tomato varieties were administrated to normal rats for 4 weeks. At the end of the experiment, an oral glucose tolerance test (OGTT) was performed. Rats were fed once and then dissected. According to the OGTT results, plasma glucose levels in the LR group were 10% and 9% lower at 15 min and 30 min, respectively, than those in the NC group, whereas plasma insulin levels did not differ between the groups at either time point. Upon dissection, plasma leptin levels in the LR group were higher than those in the NC group, while plasma adiponectin levels did not differ between groups. With the exception of retinol palmitate, no carotenoids were detected in the liver by HPLC analysis. Hepatic retinol palmitate levels and hepatic triacyl glyceride levels did not differ between the groups. We concluded that in normal rats, a lycopene-rich tomato variety improved glucose tolerance via an increase in plasma leptin levels that enhanced insulin sensitivity but did not affect carotenoid accumulation or lipid metabolism.

High-fructose diets are associated with not only fat accumulation in liver but also blood adipokine levels. Some studies have shown the involvement of humoral factors in the regulation of adipokines. However, the role of the vagus nerve in expression of adipokines is not fully understood. We attempted to investigate the involvement of the hepatic branch of the vagus nerve (HBVN) in the regulation of plasma adipokine levels in rats fed a high-fructose (HFr) diet. Rats underwent hepatic vagotomy (Vx) or sham operation; thereafter, they were fed a control diet (CT) or HFr diet for 6 weeks. At the sixth week, the oral glucose tolerance test (OGTT) was performed. In the sham-operated group, plasma leptin and adiponectin levels were significantly lower in the HFr group than those in the control group. In contrast, in the Vx group, there was no difference in the respective adipokine levels of the two dietary groups. In OGTT, plasma leptin levels were significantly correlated to the area under the curve (AUC) of plasma insulin levels and insulin levels at some points. Further, the ratio of plasma leptin levels to plasma adiponectin levels was correlated with the AUC of plasma insulin levels. However, the plasma adiponectin level itself did not correlate with plasma insulin levels and insulin AUC. Thus, we showed that HBVN played a key role in down-regulating plasma leptin and adiponectin levels in HFr-fed rats.

ATP binding cassette transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), are expressed in skin, but their involvement in transdermal absorption of clinically used drugs remains unknown. Here, we examined their role in transdermal absorption of corticosteroids. Skin and plasma concentrations of dexamethasone after dermal application were reduced in P-gp and BCRP triple-knockout (Mdr1a/1b/Bcrp−/−) mice. The skin concentration in Mdr1a/1b/Bcrp−/− mice was reduced in the dermis, but not in the epidermis, indicating that functional expression of these transporters in skin is compartmentalized. Involvement of these transporters in dermal transport of dexamethasone was also supported by the observation of a higher epidermal concentration in Mdr1a/1b/Bcrp−/− than wild-type mice during intravenous infusion. Transdermal absorption after dermal application of prednisolone, but not methylprednisolone or ethinyl estradiol, was also lower in Mdr1a/1b/Bcrp−/− than in wild-type mice. Transport studies in epithelial cell lines transfected with P-gp or BCRP showed that dexamethasone and prednisolone are substrates of P-gp, but are minimally transported by BCRP. Thus, our findings suggest that P-gp is involved in transdermal absorption of at least some corticosteroids in vivo. P-gp might be available as a target for inhibition in order to deliver topically applied drugs and cosmetics in a manner that minimizes systemic exposure. © 2017 Elsevier B.V., Embargo Period 12 months

P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are xenobiotic transporters which pump out variety types of compounds, but information on their interaction with endogenous substrates in the skin is limited. The purpose of the present study was to clarify possible association of these transporters in dermal accumulation of inflammatory mediators. Dermatitis model was constructed by repeated topical application of oxazolone in wild-type, and P-gp and BCRP gene triple knockout (Mdr1a/1b/Bcrp−/−) mice to observe difference in phenotype. Target metabolome analysis of 583 metabolites was performed using skin and plasma. Dermatitis and scratching behavior in dermatitis model of Mdr1a/1b/Bcrp−/− mice were more severe than wild-type mice, suggesting protective roles of these transporters. This hypothesis was supported by the metabolome analysis which revealed that concentration of histamine and other dermatitis-associated metabolites like urate and serotonin in the dermatitis skin, but not normal skin, of Mdr1a/1b/Bcrp−/− mice was higher than that of wild-type mice. Gene expression of P-gp and BCRP was reduced in oxazolone-treated skin and the skin of patients with atopic dermatitis or psoriasis. These results suggest possible association of these efflux transporters with dermal inflammatory mediators, and such association could be observed in the dermatitis skin.

Flavonoids purportedly have a role in improving lipid metabolism. In our preliminary study, highly concentrated flavonoid metabolites appeared in bile juice in rats, which also contains various lipids. Biliary flavonoid metabolites generally have amphiphilic properties, may influence lipid solubility, and possibly contribute to the improvement of dyslipidemia. However, the influence of biliary flavonoid metabolites on the biliary lipid profile is not well known. Therefore, we hypothesized that the amphiphilic property of biliary flavonoid metabolites alters biliary lipid profiles. To estimate the influence of flavonoids on the biliary lipid profile, we laparotomized rats under anesthesia, intraduodenally injected them with cyanidin-3-glucoside chloride (C3G) or quercetin, and analyzed their biliary metabolite concentrations for 2 hours. Concentrations of C3G and quercetin metabolites peaked at 30 minutes after the injection; those of quercetin were 6 to 10 times higher than those of C3G throughout the sampling period up to 2 hours. Biliary triglyceride (TG) concentrations were higher in the C3G group at 30 and 45 minutes; biliary cholesterol and phospholipid concentrations were lower in the quercetin group at 30 minutes than those in the control group. Hepatic TG content after the 2-hour sampling was lower in the C3G group than in the control group. These results suggest that C3G, but not quercetin, may transiently promote TG excretion into bile, with a reduction in hepatic TG content. This C3G effect may be involved in improvement of TG metabolism.

Transdermal or as also referred to cutaneous or skin microdialysis is a sampling and monitoring technique for testing drug concentrations in the extracellular fluid of the skin, has been developed during the last decades. Its early applications aimed to determine the transdermal drug delivery by pharmacokinetic and/or toxicokinetic characterization of drug penetration through the skin. Being a minimally invasive technique its employment in human volunteers run in parallel with the preclinical animal experiments. With the discovery of topical drug absorption enhancers (both active and passive) it became more and more important to study the dermal absorption of the unbound, pharmacologically active form of certain molecules in vivo in the living tissue. This review gives an overview about iontophoretic drug delivery studies and also on the assessment of dermal drug formulations followed and evaluated by transdermal microdialysis. The new foci of the application of skin microdialysis techniques are the drug transporter interaction studies on the cutaneous barrier and the disease-related biomarker studies in dermatological research. At the final part of this review complementary technologies are presented and compared with transdermal microdialysis. In summary, transdermal microdialysis technique is a traditional in vivo method for investigating the alterations of the biochemical milieu in the skin. It is an important element of the toolbox of preclinical and clinical dermal pharmacokinetic/pharmacodynamic assays. The advancement in dermatopharmacology and pharmaceutical formulation technology, disease biomarker studies and also the development of drug–drug, drug–transporter interaction research open new horizons both for the experimental and clinical applications of this assay.

The role of two ATP binding cassette transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), in transdermal absorption of a typical common substrate was examined in vivo. Skin and plasma concentrations of rhodamine123 (Rho123) after dermal application were reduced in P-gp knockout (mdr1a/1b⁻/⁻) mice and were below the detection limit in P-gp and BCRP triple-knockout (mdr1a/1b/bcrp⁻/⁻) mice. Lower epidermal-to-hypodermal permeation of Rho123 in mdr1a/1b/bcrp⁻/⁻ mouse skin compared to the wild-type mouse skin was confirmed in an Ussing-type chamber experiment. The reduction in skin concentration after dermal application in mdr1a/1b/bcrp⁻/⁻ mice was greater in the dermis than in the epidermis, suggesting functional expressions of these transporters in two distinct skin compartments. Coadministration of the inhibitor itraconazole reduced the skin and plasma concentrations of Rho123 in the wild-type mice, but not in mdr1a/1b/bcrp⁻/⁻ mice, and a marked decrease of Rho123 concentration was seen in the dermis, demonstrating that the functional activities of these transporters can be modulated in vivo. On the other hand, the distribution of Rho123 after intravenous infusion was higher in mdr1a/1b/bcrp⁻/⁻ mice than in the wild-type mice. This supports the occurrence of vectorial transport from the skin into systemic circulation, and is consistent with the immunohistochemical localization of P-gp and BCRP in mouse dermal endothelial cells. BCRP was immunohistochemically identified in human epidermis and dermal endothelial cells. Thus, our findings show that ABC transporters in different compartments of the skin contribute to transdermal absorption of a typical substrate in vivo and can be modulated by a specific inhibitor. These findings have implications for transdermal drug delivery.

To clarify the functional properties of potato pulp (PP), a waste product resulting from extraction of starch from potatoes, we examined the effects of PP on cholesterol metabolism and cecal conditions in rats. Plasma total cholesterol (T-Chol) levels were lower in rats fed a PP-supplemented diet for four weeks than in those fed a control diet. Cecal pH was lowered due to an increase in the levels of cecal total short-chain fatty acids, especially butyrate, in the PP group compared to the control group. Furthermore, animals fed with the PP-supplemented diet showed increased cecal ratios of Lactobacillus and Clostridia and decreased cecal ratios of Bacteroides and Gammaproteobacteria with slightly negative and positive correlations with plasma T-Chol levels, respectively. In conclusion, ingestion of PP for four weeks is likely to improve both cecal conditions and cholesterol metabolism, suggesting that PP has prebiotic effects.

To investigate whether yam improves glucose metabolism, yam-containing diets were given to Wistar rats. In a short-term experiment, fasted-rats were given 1.0 g of a control and 20% yam-containing diets. At 60 min after start of the feeding, glucose level in the yam diet group was lower or tended to be lower than that in the control diet. Insulin levels at 30 min and 60 min were significantly lower than those in the control group. In a long-term experiment, a normal diet (N) or 25% high fat diets with (Y) or without 15% yam powder (HF) were given to rats for 4 weeks. At 4 weeks, in an oral glucose tolerance test, the area under the curve (AUC) of plasma glucose level was higher in the HF group than that in the N group, whereas those in the Y groups did not differ from that in the N group. Glycosylated hemoglobin levels had similar tendency to the AUCs. Plasma leptin levels in the Y groups were significantly higher than that in the N group. In conclusion, yam may contribute to improvement of glucose metabolism. Additionally, we speculated that leptin level is possibly involved in the insulin-response to yam diets.

We examined the effects of white wheat bread powder (BP) and white wheat bread powder containing sugar beet fiber (BBP) on serum cholesterol. The total cholesterol (-11%, -16%), HDL-cholesterol (-12%, -11%), non-HDL-cholesterol (-9%, -18%) and triacylglycerol (-44%, -58%) concentrations in the BP and BBP groups, respectively, were significantly different from those in the control group. The fecal excretion of neutral sterols in the BP and BBP groups and of acidic sterols in the BBP group was significantly higher than that in the control group. The hepatic cholesterol 7alpha-hydroxylase (CYP7A1) mRNA level in the BP and BBP groups was significantly higher than that in the control group. The cecal total short-chain fatty acid concentrations in the BBP group were significantly higher than those in the control group. These results indicate that the observed changes in serum lipid levels in the BP and BBP groups were due to the increased fecal lipid and CYP7A1 mRNA levels.

Background/Aims: Feeding rats potato resistant starch improves large bowel health; however, there is little information on the physiological effects of preprocessed starch like potato flakes in animal experiments. The present study was designed to investigate the effects of the consumption of various colored potato (white, red and purple) flakes on cecal fermentation and fecal bile acid excretions in rats. Methods: The control group was fed a basal diet (BD) containing α-cornstarch for 4 weeks. The potato flake-treated groups were fed one of the following diets containing a mixture of 299.5 g/kg α-cornstarch plus 250 g/kg Hokkai kogane flakes (HK, white), Hokkai No. 91 flakes (H91, red) or Hokkai No. 92 flakes (H92, purple). Results: There were no significant differences in the body weight, food intake and cecum weight among the groups. Cecal pH values in the HK, H91 and H92 groups were significantly lower than that in the BD group, and matter excretion in the H91 group was significantly higher than in the BD and HK groups. Cecal short-chain fatty acid (SCFA) concentrations in the HK, H91 and H92 groups were significantly higher than in the BD group, and the molar ratio of butyrate to total SCFA in the HK, H91 and H92 groups was greatly increased compared with the BD group. Rats fed the HK, H91 and H92 potato flake diets presented significantly higher counts of total anaerobes in the cecum than rats fed the BD. The cecal Lactobacillus count in the H91 group was significantly increased compared to the BD group and the Bifidobacterium count was similar for all groups. Fecal total bile acid excretion in the H92 flake group and secondary bile acid excretions in the H91 and H92 groups were significantly greater than those in the other groups and in the BD and HK groups, respectively. Conclusion: The results indicate that potato flakes act like resistant starch and raise bowel SCFA, probably through anaerobic bacterial activities and fermentation of residual starch. These actions are helpful for the improvement of the colonic environment.

The protective effects of red potato extract (RPE) as to liver damage were determined in D-galactosamine (GalN)-intoxicated rats. Increases in serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase activities, all of which were induced by GalN injection, decreased in RPE administered rats, suggesting that RPE acts as a functional food showing anti-hepatotoxicity.

We investigated the hepatoprotective effect of purple potato extract (PPE) against D-galactosamine (GalN)-induced liver injury in rats. PPE (400 mg) was administered once daily for 8 d, and then GalN (250 mg/kg of body weight) was injected at 22 h before the rats were killed. Serum tumor necrosis factor alpha (TNF-alpha), lactate dehydrogenase (LDH), alanine aminotransferase (ALT), and asparate aminotranferase (AST) levels increased significantly after injection of GalN, but PPE inhibited GalN-induced alterations in serum TNF-alpha, LDH, ALT, and AST levels. Hepatic lipid peroxide and glutathione levels in the control + GalN group were higher and lower respectively than those in the control group, and those in the PPE + GalN group did not differ from that in the control group. The lipid peroxide level in hepatic microsomes treated with 2,2'-azobis (2-amidinopropane) dihydrochloride in the PPE group was significantly lower than that in the control group. This suggests that PPE has hepatoprotective effects against GalN-induced hepatotoxicity via inhibition lipid peroxidation and/or inflammation in rats.

application/pdf, In our previous study, we demonstrated that retrograded starch, a kind of resistant starch, of beans reduced serum lipid levels in rats. In this study, we examined whether retrograded starch in potato pulps could reduce serum lipid concentrations. Rats were given diets containing 15 g of retrograded starch in potato pulps from the Benimaru potato (BM) or Hokkaikogane potato (HK) in a 100 g diet for 4 wk. At the 4th week, the total cholesterol level in the serum in the BM group and serum triglyceride (TG) level in the HK group were significantly lower than those in the control group. In the BM group, the contents of fecal bile acids were significantly higher than those in the control group. On the other hand, in the HK group, the hepatic mRNA level of fatty acid synthase (FAS) was significantly lower than that in the control group. The FAS mRNA level correlated with the mRNA level of sterol regulatory element-binding protein-1c (SREBP-1c), a regulator of expression of FAS, positively. These results suggested that BM pulp promoted the excretion of bile acids, which resulted in a low concentration of serum cholesterol. On the other hand, HK pulp inhibited the synthesis of fatty acids at the mRNA levels of FAS and SREBP-1c, which might lead to a reduction of the serum TG level., 日本ビタミン学会、日本栄養・食糧学会共同編集

In acute hepatic injury tests, an adzuki bean extract decreased D-galactosamine (GalN)-induced alterations in the serum alanine aminotransferase and aspartate aminotranferase activities to about 37% and 25%, respectively, although there were no significant differences in these activities between the GalN-treated group with the adzuki bean extract and the GalN-treated group without the adzuki bean extract. Furthermore, the hepatic glutathione peroxidase, glutathione reductase, and Mn- and Cu,Zn-superoxide dismutase mRNA levels in the GalN-treated group with the adzuki bean extract were higher than those in the control group and GalN-treated group without the adzuki bean extract.

We investigated the cholesterol-lowering effect of a potato ethanol residue (PER). The plasma cholesterol levels excluding high-density lipoprotein cholesterol were lower in the rats given a PER-containing diet for 6 weeks than in the control group, whereas the fecal cholesterol levels were higher. These results suggest that PER partially reduced plasma cholesterol levels via excretion of cholesterol into the feces.

Regulators for pancreatic amylase were examined. Rats were fed ad libitum a 20% amino acid (AA) mixture diet (Con), a 60% AA diet (HA), a branched-chain amino acid (BCAA)-rich diet (BC), or a diet supplemented with AA other than BCAA (OA) for 7 d, or fed the Con, HA, BC diets or diets supplemented with individual BCAA. Activity and mRNA levels of pancreatic amylase in the BC and HA groups were lower than those in the Con and OA groups. Leucine and isoleucine contributed to these effects of the BC diet. The mRNA levels correlated with individual pancreatic BCAA concentrations but not with plasma insulin level. In conclusion, dietary BCAA, especially leucine and isoleucine, may reduce amylase mRNA and activity in rats.

In some tissues, amino acids (AA) stimulate translation initiation via interactions between eukaryote initiation factor (elF) 4E-binding protein 1 (4E-BP1), elF4E and elF4G. Dietary AA have been shown to induce pancreatic proteases independently of cholecystokinin in rats, the mechanism of which has not yet been clarified. In the present study, we examined the mechanism in rats for protease induction by dietary AA and determined the involvement of translation initiation. Male Wistar/ST rats were fed a 20 or 60% casein or AA mixture diet for 7 d and were intravenously injected with [ 35 S] methionine (Met) 30 min before killing on d 7 (expt. 1). In expt. 2, rats were fed a 20 or 60% AA diet for 7 d and after food deprivation and refeeding with the respective diet on d 7 were killed at 0, 1 or 3 h. We measured mRNA and [ 35 S] Met incorporation into chymotrypsinogen, phosphorylation status of 4E-BP1 and the association of elF4E with 4E-BP1 or elF4G. In expt. 1, chymotrypsin activity and synthesis were higher in both of the 60% diet groups than in the 20% diet groups, but the mRNA level and 4E-BP1 status did not differ. In expt. 2, chymotrypsin activity increased in the 60% AA diet group in a time-dependent manner. The translation initiation activity via the mTOR pathway indicated an increase similar to chymotrypsin activity. There were no differences in chymotrypsin mRNA level at any point. These results indicate that dietary AA induce chymotrypsin synthesis by promoting translation, and transient activation of translation initiation via mTOR may be associated with this induction.

The authors recently developed a primate thromboembolic stroke model. To characterize the primate model, the authors determined serial changes in cerebral blood flow (CBF) and the relation between CBF and cerebral metabolic rate of glucose (CMRglc) using high-resolution positron emission tomography. Thromboembolic stroke was produced in male cynomolgus monkeys (n = 4). Acute obstruction of the left middle cerebral artery was achieved by injecting an autologous blood clot into the left internal carotid artery. Cerebral blood flow was measured with [15O]H2O before and 1, 2, 4, 6, and 24 hours after embolization. CMRglc was measured with 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG) 24 hours after embolization. Lesion size and location 24 hours after embolization was determined by the 2,3,5-triphenyltetrazolium chloride (TTC) staining method. The results are summarized as follows: (1) 1 hour after embolization, CBF in the temporal cortex and the basal ganglia decreased to < 40% of the contralateral values. In these regions, regarded as an ischemic core, CBF decreased further with time and CMRglc at 24 hours also decreased. Infarcted lesions as indicated by being unstained with TTC were consistently observed in these regions. (2) In the parietal cortex and several regions surrounding the ischemic core, CBF was >40% of the contralateral values 1 hour after embolization and recovered gradually with time (ischemic penumbra). In these regions, CMRglc at 24 hours increased compared with that in the contralateral regions, indicating an uncoupling of CBF and CMRglc. No obvious TTC-unstained lesions were detected in these regions. The authors demonstrated a gradual recovery of reduced CBF, an elevated CMRglc and a CBF-CMRglc uncoupling in the penumbra regions of the primate model. Positron emission tomography investigations using this model will provide better understanding of the pathophysiology of thromboembolic stroke in humans.

To clarify the effects of spreading depression (SD) on cerebral circulation and metabolism, we elicited a single or repetitive episode of SD and evaluated CBF and CMRglc three-dimensionally in normal cats (n=4, in each group) using a high-resolution positron emission tomography (PET) scanner. SD was evoked by applying KCl to the left occipital cortex. We then monitored DC potential changes with tungsten electrodes inserted into the left temporal cortex. CBF was measured twice before and three times (immediately, 30-60 min, and 60-120 min) following KCl application using [15O]H(2)O, and CMRglc was determined using 2-[18F]fluoro-2-deoxy-D-glucose immediately following the last CBF measurement. The following results were obtained: (1) a single episode of SD produced a temporary CBF increase, followed by a long-lasting hypoperfusion in the cortex, with no significant changes to CBF observed in the subcortex; (2) no significant CMRglc changes were observed in either cortical or subcortical regions following a single episode of SD; (3) a flow-metabolism uncoupling was observed in the cortical regions concurrently with persistent hypoperfusion; (4) repetitive SD produced significant CBF changes in the cortex; and (5) the cortical CMRglc increased as a result of repeated episodes of SD, with no significant changes observed in the subcortex. Thus, we succeeded in determining three-dimensionally the effects of single and repetitive SD on CBF and CMRglc in cats using a high-resolution PET scanner. The present study provides the first direct evidence of CBF-CMRglc uncoupling occurring concurrently with persistent hypoperfusion following SD.

Octanoate is taken up into the brain and is converted in astrocytes to glutamine through the TCA cycle after beta-oxidation. We speculate that [1-11C]octanoate may be used as a tracer for astroglial functions and/or fatty acid metabolism in the brain and may be useful for studying cerebral ischemia. In the present study we investigated brain distribution of [1-11C]octanoate and compared it with cerebral blood flow (CBF) by using rat and canine models of middle cerebral artery (MCA) occlusion and a high resolution PET. In rats brain distribution of [15O]H2O measured 1-2 h and 5-6 h after insult was compared with that of [1-11C]octanoate measured 3-4 h after insult. Radioactivity ratios of lesioned to normal hemispheres determined with [15O]H2O were lower than those determined with [1-11C]octanoate. These results were confirmed by a study on a canine model of MCA-occlusion. Twenty-four hours after insult, CBF decreased in the MCA-territory of the occluded hemisphere, whereas normal or higher accumulation of [1-11C]octanoate was observed in the ischemic regions. The uptake of [1-11C]octanoate-derived radioactivity therefore increased relative to CBF in the ischemic regions, indicating that [1-11C]octanoate provides functional information different from CBF. In conclusion, we found that [1-11C]octanoate is a potential radiopharmaceutical for studying the pathophysiology of cerebral ischemia.

We have established a convenient synthesis process for the synthesis of [18F]haloperidol using a single-step 18F - for - Cl exchange reaction and a new elution system for the preparative high performance liquid chromatography (HPLC) using C18 bonded vinylalcohol copolymer gel (ODP) and a basic eluent. We successfully applied the product to cat-PET study and got clear images of the striatum, showing the usefulness of this synthesis.

To examine the reliability of quantitative positron emission tomography studies in the rat (Rat–PET), we assessed the influence of radioactivity accumulated in the Harderian glands on PET CMRglc determination. We measured CMRglc by PET and ex vivo dissection methods by using 2-[18F]fluoro-2-deoxy-D-glucose in rats with and without focal brain ischemia. The CMRglc values obtained by PET, after correcting with recovery coefficients, were higher than those measured by the ex vivo method at rostral slices, and reduction of the CMRglc in the ischemic brain was not demonstrated by PET in the frontal cortex. The radioactivity accumulated in the Harderian glands prevents the quantitative determination of CMRglc using Rat–PET.

To evaluate the ability of [1-11C]octanoate as a PET tracer for imaging the brain, we examined its distribution in the brain and surrounding tissues in rats and cats with PET. In rats, owing to the accumulated radioactivity in the harderian glands, clear brain images were not obtained at rostral levels. In cats, the brain was imaged clearly at every level of the coronal brain slices, suggesting the potential of [1-11C]octanoate for imaging the brain.

We examined the effects of different types of buckwheat sprouts on the plasma cholesterol concentration, fecal steroid excretion and hepatic mRNA expression related to cholesterol metabolism in rats. Rats were fed a cholesterol-free diet with 5 g of Kitawasesoba common buckwheat sprout powder (KS)/100 g, 5 g of Hokkai T no. 8 tartary buckwheat sprout powder (HS-8)/100 g or 5 g of Hokkai T no. 9 tartary buckwheat sprout powder (HS-9)/100 g of diet for 4 wk. Control rats were fed a diet with alpha-cornstarch instead of sprout powder for 4 wk. There were no significant differences in food intake, body weight, liver weight or cecal contents among the groups. Plasma total cholesterol concentrations in the HS-8 and HS-9 groups were significantly lower than in the control group, whereas there was no significant difference between the KS and control groups. Fecal bile acid excretion and cecal short-chain fatty acid concentrations in the KS, HS-8 and HS-9 groups were significantly greater than in the control group. Furthermore, fecal matter excretion in the KS, HS-8 and HS-9 groups tended to be increased compared to the control group, with that in the HS-8 group being significantly higher than in the control group. Hepatic cholesterol 7alpha-hydroxylase mRNA expression in the KS, HS-8 and HS-9 groups and hepatic HMG-CoA reductase mRNA expression in the HS-9 group were significantly higher than in the control group. The results suggest that tartary buckwheat sprout powder has a serum cholesterol-lowering function by enhancing fecal bile acid excretion through increased fecal matter excretion or the upregulation of hepatic cholesterol 7alpha-hydroxylase mRNA expression in rats.

application/pdf, Excessive consumption of alcoholic beverages is a serious cause of liver disease worldwide. The meta-bolism of ethanol generates reactive oxygen species, which play a significant role in the deterioration of alcoholic liver disease (ALD). Antioxidant phytochemicals, such as polyphenols, regulate the expression of ALD-associated proteins and peptides, namely, catalase, superoxide dismutase, glutathione, glutathione peroxidase, and glutathione reductase. These plant antioxidants have electrophilic activity and may induce antioxidant enzymes via the Kelchlike ECH-associated protein 1-NF-E2-related factor-2 pathway and antioxidant responsive elements. Furthermore, these antioxidants are reported to alleviate cell injury caused by oxidants or inflammatory cytokines. These phenomena are likely induced via the regulation of mitogen-activating protein kinase (MAPK) pathways by plant antioxidants, similar to preconditioning in ischemia-reperfusion models. Although the relationship between plant antioxidants and ALD has not been adequately investigated, plant antioxidants may be preventive for ALD because of their electrophilic and regulatory activities in the MAPK pathway.

application/pdf, We examined the physiological importance of bovine dietary proteins in rats fed diets prepared from bovine Achilles’tendons and arteries. Rats were fed for 4 weeks, with 20% casein diet (CON), in comparison with two diets containing 15% casein and 5% of either bovine Achilles’ tendons (AC) or arteries (AR) protein preparations. The serum total cholesterol concentration and non-HDL cholesterol level in the AR fed group were significantly lower (P

Poly(adenosine diphosphate-ribose) synthetase (PARS) is a nuclear enzyme that is activated by deoxyribonucleic acid (DNA) strand breaks and participates in DNA repair. Excessive PARS activation, however, leads to cell death due to depletion of adenosine triphosphate (ATP). To evaluate whether it is possible to detect excessive activation of PARS with positron emission tomography (PET), we examined the pharmacokinetics of 3,4-dihydro-5-[ 11 C]methoxy-1(2H)-isoquinolinone ([ 11 C]MIQO), a potent poly(ADP-ribose) synthetase inhibitor, in the brain of rats and monkeys. Although the uptake of [ 11 C]MIQO in the brain of normal rats was low, [ 11 C]MIQO was rapidly incorporated into and then quickly washed out from the brain. The uptake of the radiotracer in the brain of normal monkeys was also low; however, [ 11 C]MIQO gave a distribution image that differed from that of cerebral blood flow obtained by [ 15 O]water-PET. No localization of [ 11 C]MIQO in the brain of normal monkeys was observed. Low accumulation of some radioactivity was also observed in muscles surrounding the brain of monkeys, but did not seem to interfere with measurement of [ 11 C]MIQO uptake in the brain with PET. Thus, detection of [ 11 C]MIQO uptake with PET may be useful for detecting PARS activity in ischemic injury.

Octanoate is taken up by the brain and converted in astrocytes to glutamine through the TCA cycle after beta-oxidation. Consequently, [1-11C]octanoate might serve as a useful positron emission tomography (PET) probe for studying cerebral oxidative metabolism and/or astroglial functions. The present study attempted to evaluate the utility of using [1-11C]octanoate as a PET tracer for imaging and evaluating the pathophysiology of ischemic stroke. We used a canine model of thromboembolic stroke. Five male beagle dogs were implanted with an indwelling catheter in the left internal carotid artery. A single autologous blood clot was injected into the left internal carotid artery through the catheter. The brain distribution of [1-11C]octanoate and cerebral blood flow (CBF) were determined 24 h after insult using a high resolution PET scanner. Post mortem brain regions unstained with 2,3,5-triphenyltetrazolium chloride (TTC) were defined as infarcts. In the region of an infarct, accumulation of [1-11C]octanoate decreased concurrently with CBF reduction. In contrast, normal accumulation of [1-11C]octanoate was observed in ischemic but vital regions, suggesting that an increased accumulation of [1-11C]octanoate relative to CBF takes place in these regions. In conclusion, [1-11C]octanoate accumulated in ischemic but vital regions, indicating that [1-11C]octanoate is a potentially useful PET tracer for imaging and evaluating the pathophysiology of ischemic stroke.

To evaluate the potential of [1- 11 C]-3-(R,S)-methyloctanoate (BMOA), [1- 11 C]-2-octynoate, and [1- 11 C]-2-decynoate as PET tracers for studying particular steps in fatty acid β-oxidation, we examined the pharmacokinetics of these compounds in rats and a cat. In rats given these compounds, high levels of radioactivity accumulated in the heart, liver, and kidneys, suggesting their potential as tracers for studying β-oxidation in these tissues. These organs were clearly visible with PET in a cat given BMOA, indicating the utility of BMOA for imaging these organs.

The uptake of octanoate in rat brain and its metabolism were investigated by means of intravenously injecting [1-11C] or [1-14C]octanoate as a tracer. The radioactivity in the cerebrum was increased by an injection of [1-11C]octanoate, and reached its peak level (0.33% ID/g) in about 2 to 5 min, and then decreased slowly. The cerebrum-to-blood ratio of the radioactivity increased with time over a period of 30 min. At 30 sec, [ 1-11C]octanoate that remained unchanged in the cerebrum accounted for only 8% of the total radioactivity, in spite of there being about 90% in the blood. By means of an injection of [ 1-14C]octanoate, more than 70% of the total radioactivity in the cerebrum was found to be attributable to radiolabeled glutamate and glutamine at each time point measured between 30 sec and 30 min. The results show that [1-11C]octanoate enters rat brain easily and is trapped in the cerebrum, probably in the form of glutamate and glutamine, and the usefulness of [ 1-11C] octanoate as a radiopharmaceutical for studying brain fatty acid metabolism by positron emission tomography is therefore suggested.

As part of our recent search for new semisynthetic analogs of maytansinoids having a better therapeutic ratio than maytansine, we synthesized 3-epimaytansinoids (VIIIa-c) starting from ansamitocin P-3, a fermentation product of Nocardia sp., via maytansinol (I). A key intermediate, 3-epimaytansinol (VI), was synthesized by oxidation of I with pyridinium chlorochromate to 3-maytansinone (IV), followed by stereoselective reduction with NaBH4. Esterification of VI with appropriate carboxylic acids gave the corresponding 3-epimaytansinoids (VIIIa-c) in high yields. These compounds did not show the biological activity characteristic of natural maytansinoids to any appreciable degree.

Several semisynthetic maytansinoids that differ in the structure of the acyl group at the C3 position were prepared by acylation of maytansinol (3) using appropriate carboxylic acids or their active derivatives, and the effects of the compounds on the growth of Tetrahymena pyriformis and the survival of tumor-bearing mice were determined. Among these analogs, the C3 esters having a straight chain aliphatic acyl (11, 12), cycloalkanecarbonyl (18-20) or phenylacetyl group (22), and those having a 2-(N-acetyl-N-methyl) aminohexanoyl (7) or (2-(N-acetyl-N-methyl) aminophenylpropionyl group (8), strongly inhibited the growth of T. pyriformis and exhibited potent activity against B16 melanoma in mice. The potencies were similar to those of maytansine and ansamitocin P-3. The most striking result was the finding that the phenylglycinate (31) was superior to maytansine in terms of its broader effective dose range against ip B16 melanoma and P388 leukemia in mice ; however, higher doses of the phenylglycinate were required.