Acute chemotherapy-induced peripheral neuropathy due to oxaliplatin administration without cold stimulation.

PURPOSE: The incidence and time of onset of acute chemotherapy-induced peripheral neuropathy (ACIPN) caused by oxaliplatin remain unclarified. Hence, we investigated the prevalence, onset time, and location of ACIPN symptoms in patients with colorectal cancer (CRC) receiving oxaliplatin without cold stimulation. METHODS: The study cohort comprised patients receiving oxaliplatin for CRC at our hospital between April 2017 and August 2018. Patients were instructed not to touch and/or drink cold things and were monitored for ACIPN symptoms in the hospital for 24 h after chemotherapy. ACIPN symptoms that appeared > 24 h after chemotherapy were recorded at the next visit. Symptom appearance time was defined as the duration from the administration of chemotherapy until the appearance of paresthesia classified as grade 1 using the Common Terminology Criteria for Adverse Events. RESULTS: Forty-five patients received chemotherapy, comprising 23 men and 22 women, aged 67 years (29-88 years). The location of ACIPN was the fingers in 55.6% of cases, pharynx in 26.7%, perioral region in 24.4%, and feet in 6.7%. The average duration from oxaliplatin administration to symptom development was 182 min (range 62-443 min) for the fingers, 291 min (176-432 min) for the pharynx, 311 min (127-494 min) for the perioral region, and 297 min (234-355 min) for the feet. Pharyngeal symptoms were more common in patients older than 65 years than in those younger than 65 years. CONCLUSIONS: The incidence and time of the onset of ACIPN caused by oxaliplatin varies between the body and regions.

A proposal on the first Japanese practical guidance for the return of individual genomic results in research settings.

Large-scale, low-cost genome analysis has become possible with next-generation sequencing technology, which is currently used in research and clinical practice. Many attempts of returning individual genomic results have commenced not only in clinical practice, but also in research settings of several countries. In Japan, the government guidelines include a section on the disclosure of genetic information regarding genome analysis in research. However, no practical guidance for the return of individual genomic results in research settings (ROGRR) currently exists. We propose practical guidance regarding ROGRR in Japan based on extensive research, including a literature review of related previous studies, an examination of the relevant legislation in Japan, and interviews with stakeholders. The guidance we developed consists of "Points to consider" and "Issues for further discussion and consideration." The "Points to consider" were divided into five parts, from preliminary review before discussion of policy, to the actual return and follow-up process, in the order of the assumed ROGRR process. It is anticipated that a situation will arise where numerous research projects will consider ROGRR carefully and realistically in the future, and in the process of drafting such practical guidance, various issues requiring continuous discussion will emerge. The necessities of continuous discussion concerning ROGRR in Japan's context is increasing, particularly in terms of the ethical, legal, and social implications. We believe such discussions and considerations may contribute to creating a new system that will increase availability of personalized medicine and prevention using genetic information, allowing them to become useful to the broader population.

Public attitudes in Japan toward participation in whole genome sequencing studies.

BACKGROUND: Recent innovations in gene analysis technology have allowed for rapid and inexpensive sequencing of entire genomes. Thus, both conducting a study using whole genome sequencing (WGS) in a large population and the clinical application of research findings from such studies are currently feasible. However, to promote WGS studies, understanding and voluntary participation by the general public is needed. Therefore, it is essential to investigate the general public's attitude toward and understanding of WGS studies. The primary goal of our research is to investigate these issues and to discover how they relate to research participation in WGS studies. METHODS: A survey of awareness regarding WGS and studies using WGS was conducted with a sample of 2000 or more participants using a self-administered questionnaire posted on the Internet between February 20 and 21, 2015. Prior to the survey, we briefly explained WGS and WGS study-related issues to the respondents in order to provide them with the minimum knowledge required to answer the questionnaire. We then conducted an analysis, including cross-classification. RESULTS: For the question regarding interest in WGS, 46.6% of participants responded "Yes." 70.7% of all respondents said that they were interested in some kinds of findings that could be obtained from WGS studies. Regarding participation in WGS studies, 29.0% were interested in participating. The demographic factors significantly related to attitudes toward research participation were age, level of education, and employment status. The results also suggest that concerns about WGS have a positive effect on people's willingness to participate. Furthermore, it was shown that for people who were not interested in their gene-related information, concerns about WGS negatively impacted their willingness to participate. However, for people who were interested in their gene-related information, their concerns might not have impacted their willingness to participate. DISCUSSION AND CONCLUSIONS: This research has shown several key factors that affect the willingness of the general public for the participation to the WGS studies. One of the unexpected findings is that concerns toward WGS studies generally have positive effect on the peoples' attitude. It will be interesting to further investigate into the various types of concerns that people in different groups have about WGS.

MGAT2 deficiency ameliorates high-fat diet-induced obesity and insulin resistance by inhibiting intestinal fat absorption in mice.

BACKGROUND: Resynthesis of triglycerides in enterocytes of the small intestine plays a critical role in the absorption of dietary fat. Acyl-CoA:monoacylglycerol acyltransferase-2 (MGAT2) is highly expressed in the small intestine and catalyzes the synthesis of diacylglycerol from monoacylglycerol and acyl-CoA. To determine the physiological importance of MGAT2 in metabolic disorders and lipid metabolism in the small intestine, we constructed and analyzed Mgat2-deficient mice. RESULTS: In oral fat tolerance test (OFTT), Mgat2-deficient mice absorbed less fat into the circulation. When maintained on a high-fat diet (HFD), Mgat2-deficient mice were protected from HFD-induced obesity and insulin resistance. Heterozygote (Mgat2+/-) mice had an intermediate phenotype between Mgat2+/+ and Mgat2-/- and were partially protected from metabolic disorders. Despite of a decrease in fat absorption in the Mgat2-deficient mice, lipid levels in the feces and small intestine were comparable among the genotypes. Oxygen consumption was increased in the Mgat2-deficient mice when maintained on an HFD. A prominent upregulation of the genes involved in fatty acid oxidation was observed in the duodenum but not in the liver of the Mgat2-deficient mice. CONCLUSION: These results suggest that MGAT2 has a pivotal role in lipid metabolism in the small intestine, and the inhibition of MGAT2 activity may be a promising strategy for the treatment of obesity-related metabolic disorders.

Estimation of transporters involved in the hepatobiliary transport of TA-0201CA using sandwich-cultured rat hepatocytes from normal and multidrug resistance-associated protein 2-deficient rats.

N-[6-[2-[(5-Bromo-2-pyrimidinyl)oxy]ethoxy]-5-(4-methylphenyl)-4-pyrimidinyl]-4-(2-hydroxy-1,1-dimethylethyl) benzenesulfonamide sodium salt (TA-0201) carboxylic acid form (TA-0201CA) is the primary and pharmacologically active metabolite of TA-0201, which is an orally active nonpeptide antagonist for endothelin receptors. A major elimination route of TA-0201CA in rats was biliary excretion. The aim of this study was to clarify the transporters responsible for the hepatobiliary transport of TA-0201CA by in vivo pharmacokinetic study and in vitro study using sandwich-cultured rat hepatocytes (SCRH) from normal rats [Sprague-Dawley rats (SDR)] and Eisai hyperbilirubinemic rats (EHBR). After intravenous administration, TA-0201CA was extensively excreted into bile with a high biliary clearance in SDR. In contrast, the biliary clearance in EHBR was lower than that in SDR. These results indicated that multidrug resistance-associated protein 2 (Mrp2) was partly involved in the biliary excretion of TA-0201CA. In SCRH, the hepatic uptake of TA-0201CA was significantly decreased by the presence of organic anion-transporting polypeptide (Oatp) substrates/inhibitors and a Na(+)-free condition, which is a driving force of the Na(+)-taurocholate cotransporting polypeptide (Ntcp). The canalicular secretion of TA-0201CA was inhibited by the bile salt export pump (Bsep) inhibitor glibenclamide and by the Mrp2 inhibitor 3-[[3-[2-(7-chloroquinolin-2-yl)vinyl]phenyl]-(2-dimethylcarbamoylethylsulfanyl)methylsulfanyl] propionic acid (MK-571) in SCRH from SDR and EHBR. These results suggested that TA-0201CA was transported into hepatocytes via Oatps and Ntcp and excreted into bile via Mrp2 and Bsep in rats.

Adenovirus-mediated gene transfer and lipoprotein-mediated protein delivery of plasma PAF-AH ameliorates proteinuria in rat model of glomerulosclerosis.

Oxidative stress has been proposed to play a crucial role in glomerulosclerosis, although its in vivo demonstration has proved taxing given the difficulty of inducing gene expression in specific renal cells. In this study, we examined whether the liver-directed expression of plasma platelet-activating factor acetylhydrolase (PAF-AH) would affect the glomerular pathophysiology in Imai rats, an animal model for glomerulosclerosis. Adenovirus-mediated liver-directed gene delivery of human PAF-AH resulted in a significant increase in plasma PAF-AH activity, which was detected almost exclusively on HDL. Histological examination of rats overexpressing PAF-AH showed not only the deposition of PAF-AH in mesangial cells, but also a reduction in hydroxynonenal and matrix protein content in the glomeruli. In situ hybridization analysis was negative for human PAF-AH mRNA in the kidney, while injection of HDL abundant in PAF-AH resulted in the deposition of PAF-AH in mesangial cells. Urine protein levels did not increase in rats overexpressing PAF-AH, while those of control rats increased significantly with age. This study provides direct evidence of the in vivo role of an enzyme that degrades lipid peroxides during the progression of glomerulosclerosis. Adenovirus-mediated extrarenal gene expression and lipoprotein-mediated glomeruli-targeted protein delivery promise to be a novel therapeutic approach to glomerulosclerosis.

Fluvastatin ameliorates the hyperhomocysteinemia-induced endothelial dysfunction: the antioxidative properties of fluvastatin.

BACKGROUND: Hyperhomocysteinemia induces vascular endothelial dysfunction, contributing to a predisposition to the onset and/or progression of atherosclerosis. The major mechanism suggested for the adverse effect of homocysteine on vascular function seems to involve oxidative stress. Thus, we hypothesized that the administration of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor fluvastatin, which is experimentally demonstrated to have antioxidative properties as one of its pleiotropic effects, is a useful strategy for eliminating the detrimental events induced by hyperhomocysteinemia. METHODS AND RESULTS: In diet-induced hyperhomocysteinemic rats, we estimated oxidative stress and assessed endothelium-dependent vasodilatation. Hyperhomocysteinemia induced significant increases in urinary 8-isoprostaglandin F2alpha-III excretion and vascular superoxide generation, and impaired endothelium-dependent vasodilatation. Additional oral administration of the antioxidant fluvastatin or vitamin E, which normalized increased oxidative stress induced by hyperhomocysteinemia, ameliorated endothelial dysfunction. CONCLUSIONS: Hyperhomocysteinemia, even mild to moderate, induces endothelial dysfunction through its oxidative effect. The antioxidant fluvastatin was able to cancel out the oxidative stress induced by hyperhomocysteinemia and ameliorate endothelial dysfunction. Clinical use of fluvastatin might be a potent strategy for eliminating the detrimental events induced by hyperhomocysteinemia as well as hyperlipidemia. In addition to lowering homocysteine by means of folate supplementation, administration of the antioxidants is expected to be a potentially effective anti-homocysteine therapy.

Preservation of endothelial function by the HMG-CoA reductase inhibitor fluvastatin through its lipid-lowering independent antioxidant properties in atherosclerotic rabbits.

Recent evidence suggests that the beneficial effects of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors on entothelial function and cardiovascular ischemic events may be attributed not only to their lipid-lowering effects but also to cholesterol-lowering independent (direct) effects on the atherosclerotic vessel wall. This study was designed to test the hypothesis that fluvastatin (Flu) preserves the endothelial function by its cholesterol-lowering independent actions. Rabbits were fed a 0.5% high-cholesterol (HC) diet for 12 weeks (progression phase) and then fed the HC diet either containing or not containing Flu 2 mg/kg/day for an additional 8 weeks (treatment phase). Rabbits fed a normal diet were used as controls. Plasma total and low-density lipoprotein cholesterol concentrations did not differ during the treatment phase: Endothelium-dependent/NO-mediated relaxation (acetylcholine and A23187) was impaired in the HC diet group, whereas it was preserved in the HC plus Flu treatment group. The endothelium-independent relaxation (sodium nitroprusside) was similar between the three groups. Interestingly, aortic oxidative stress (lipid peroxides and isoprostane F(2alpha)-III contents) and NADPH oxidase component (p22phox and gp91phox) mRNA expression were increased in the HC group but not in the HC plus Flu group. The A23187-induced nitric oxide production from the aorta was increased in both HC and HC plus Flu groups. There was no significant difference in tissue endothelial-type nitric oxide synthase mRNA expression. Plaque area and intimal thickening of the aorta were significantly lowered in the HC plus Flu group. Flu treatment preserved the endothelial function associated with the decrease in markers of oxidative stress in this experiment. These beneficial endothelial effects of Flu are likely to occur independently of plasma lipid concentrations and to be mediated by its antioxidant action.

Glucuronidation of etoposide in human liver microsomes is specifically catalyzed by UDP-glucuronosyltransferase 1A1.

A metabolite formed by incubation of human liver microsomes, etoposide, and UDP-glucuronic acid was identified as etoposide glucuronide by liquid chromatography-tandem mass spectrometry analysis. According to the derivatization with trimethylsilylimidazole (Tri-Sil-Z), it was confirmed that the glucuronic acid is linked to an alcoholic hydroxyl group of etoposide and not to a phenolic group. Among nine recombinant human UGT isoforms (UGT1A1, UGT1A3, UGT1A4, UGT1A6, UGT1A8, UGT1A9. UGT1A10, UGT2B7, and UGT2B15), only UGT1A1 exhibited the catalytic activity of etoposide glucuronidation. The enzyme kinetics in pooled human liver microsomes and recombinant UGT1A1 microsomes showed a typical Michaelis-Menten plot. The kinetic parameters of etoposide glucuronidation were K(m) = 439.6 +/- 70.7 microM and V(max) = 255.6 +/- 19.2 pmol/min/mg of protein in human liver microsomes and K(m) = 503.2 +/- 110.2 microM and V(max) = was 266.5 +/- 28.6 pmol/min/mg of protein in recombinant UGT1A1. The etoposide glucuronidation in pooled human liver microsomes was inhibited by bilirubin (IC(50) = 31.7 microM) and estradiol (IC(50) = 34 microM) as typical substrates for UGT1A1. The inhibitory effects of 4-nitrophenol (IC(50) = 121.0 microM) as a typical substrate for UGT1A6 and UGT1A9, imipramine (IC(50) = 393.8 microM) as a typical substrate for UGT1A3 and UGT1A4, and morphine (IC(50) = 109.3 microM) as a typical substrate for UGT2B7 were relatively weak. The interindividual difference in etoposide glucuronidation in 13 human liver microsomes was 78.5-fold (1.4-109.9 pmol/min/mg of protein). The etoposide glucuronidation in 10 to 13 human liver microsomes was significantly correlated with beta-estradiol-3-glucuronidation (r = 0.841, p < 0.01), bilirubin glucuronidation (r = 0.935, p < 0.01), and the immunoquantified UGT1A1 protein content (r = 0.800, p < 0.01). These results demonstrate that etoposide glucuronidation in human liver microsomes is specifically catalyzed by UGT1A1.

Fluvastatin increases LDL particle size and reduces oxidative stress in patients with hyperlipidemia.

The effects of fluvastatin on levels of urinary 8-iso-prostaglandin F2alpha (iPF2alphaIII), a marker of oxidative stress, and low-density lipoprotein (LDL) particle size in serum were investigated in patients with hypercholesterolemia. After 6 months of fluvastatin therapy, levels of urinary iPF2alphaIII decreased from 1720.1 +/- 392.0 to 539.6 +/- 75.5 pg/mg (p < 0.01), and LDL particle size increased from 24.3 +/- 0.3 to 26.5 +/- 0.2 nm (p < 0.001). These changes from the treatment of fluvastatin were not correlated with those of the serum LDL cholesterol (LDL-C) levels. The results imply that fluvastatin, with its unique antioxidant property among statins, reduces oxidative stress and increases LDL particle size simultaneously in hyperlipidemic patients.

Involvement of multiple UDP-glucuronosyltransferase 1A isoforms in glucuronidation of 5-(4'-hydroxyphenyl)-5-phenylhydantoin in human liver microsomes.

In humans, orally administered phenytoin, 5,5-diphenylhydantoin, is mainly excreted as 5-(4'-hydroxyphenyl)-5-phenylhydantoin (4'-HPPH) O-glucuronide. Phenytoin is oxidized to 4'-HPPH by CYP2C9 and to a minor extent by CYP2C19, and then 4'-HPPH is metabolized to 4'-HPPH O-glucuronide by UDP-glucuronosyltransferase (UGT). In the present study, 4'-HPPH O-glucuronidation in human liver microsomes was investigated. The metabolite formed by incubation with human liver microsomes, 4'-HPPH, and UDP-glucuronic acid was identified as 4'-HPPH O-glucuronide by liquid chromatography-tandem mass spectrometry analysis. The 4'-HPPH O-glucuronosyltransferase activity in human liver microsomes was not saturated at concentrations up to 500 microM of 4'-HPPH. Any commercially available recombinant human UGTs (UGT1A1, UGT1A3, UGT1A4, UGT1A6, UGT1A9, UGT2B7, and UGT2B15) expressed in baculovirus-infected insect cells did not show detectable 4'-HPPH O-glucuronide. The 4'-HPPH O-glucuronidation in pooled human liver microsomes was inhibited by beta-estradiol as a typical substrate for UGT1A1 (IC(50) = 21.1 microM) and imipramine as a typical substrate for UGT1A4 (IC(50) = 57.7 microM). The inhibitory effects of propofol as a specific substrate for UGT1A9 (IC(50) = 167.1 microM) and emodin as a substrate for UGT1A8 and UGT1A10 (IC(50) = 287.6 microM) were not prominent. The interindividual difference in the 4'-HPPH O-glucuronidation in 14 human liver microsomes was 28.5-fold (0.023-0.656 nmol/min/mg of protein). The 4'-HPPH O-glucuronosyltransferase activity in 11 human liver microsomes was significantly (r = 0.609, P < 0.05) correlated with the 4-nitrophenol glucuronosyltransferase activity, which is catalyzed by UGT1A6 and UGT1A9. These results suggest that multiple UGT1As such as UGT1A1, UGT1A4, UGT1A6, and UGT1A9 are involved in 4'-HPPH O-glucuronidation in human liver microsomes, although the percentage contribution of each UGT1A could not be estimated. Large interindividual differences in the glucuronidation of 4'-HPPH might be responsible for the nonlinearity of the phenytoin plasma concentration or adverse reactions in humans.

Imipramine N-glucuronidation in human liver microsomes: biphasic kinetics and characterization of UDP-glucuronosyltransferase isoforms.

A method for the direct determination of imipramine N-glucuronidation in human liver microsomes by high-performance liquid chromatography with UV detection was developed. Imipramine was incubated with human liver microsomes and UDP-glucuronic acid. The Eadie-Hofstee plots of imipramine N-glucuronidation in human liver microsomes were biphasic. For the high-affinity component, the K(m) was 97.2 +/- 39.4 microM and the V(max) was 0.29 +/- 0.03 nmol/min/mg of protein. For the low-affinity component, the K(m) was 0.70 +/- 0.29 mM and the V(max) was 0.90 +/- 0.28 nmol/min/mg of protein. The imipramine N-glucuronosyltransferase activities were not detectable in two samples of human jejunum microsomes. Among recombinant UDP-glucuronosyltransferases (UGTs) in baculovirus-infected insect cells (Supersomes or Bacurosomes) or human B-lymphoblastoid cells tested in the present study (UGT1A1, UGT1A3, UGT1A4, UGT1A6, UGT1A7, UGT1A8, UGT1A9, UGT1A10, UGT2B7, and UGT2B15), only UGT1A4 showed imipramine N-glucuronosyltransferase activity. The activity in UGT1A4 Supersomes was higher than that in recombinant UGT1A4 expressed in human B-lymphoblastoid cells at all imipramine concentration tested. The kinetics of imipramine N-glucuronidation in UGT1A4 Supersomes did not fit the Michaelis-Menten plot, showing a K(m) of >1 mM. In contrast, in UGT1A4 expressed in human B-lymphoblastoid cells, K(m) was 0.71 +/- 0.36 mM and the V(max) was 0.11 +/- 0.03 nmol/min/mg of protein. Interindividual differences in the imipramine N-glucuronidation in liver microsomes from 14 humans were at most 2.5-fold. The imipramine N-glucuronosyltransferase activities in 11 human liver microsomes were significantly (r = 0.817, P < 0.005) correlated with the glucuronosyltransferase activities of trifluoperazine, a typical substrate of UGT1A4. This is the first report of the biphasic kinetics of imipramine N-glucuronide in human liver microsomes.

Greater oxidative stress in healthy young men compared with premenopausal women.

Coronary risk factors, including age, hypertension, diabetes mellitus, hyperlipidemia, and smoking, are associated with enhanced oxidative stress, which is implicated as a potential mechanism for atherogenesis and atherosclerotic cardiovascular diseases. Male sex is one of the well-known cardiovascular risk factors. We tested the hypothesis that oxidative stress is greater in men than in women. Plasma thiobarbituric acid-reactive substances (TBARS) and urinary 8-isoprostaglandin F2alpha (8-iso-PGF2alpha) were measured in 52 young men and 51 age-matched women. The subjects were healthy, were not smokers, and were not taking any medications or vitamins. Age, blood pressure, plasma cholesterol, and glucose did not differ between the groups. Baseline TBARS (2.32 +/- 0.11 [men] versus 1.87 +/- 0.09 [women] nmol/mL, P<0.01) and 8-iso-PGF2alpha (292 +/- 56 [men] versus 164 +/- 25 [women] pg/mg creatinine, P<0.05) were higher in men than in women. Supplementation of antioxidant vitamins for 4 weeks in men produced a significant reduction in TBARS and 8-iso-PGF2alpha by 34% (P<0.01) and 48% (P<0.05), respectively. Plasma superoxide dismutase, catalase, and vitamin E levels were comparable between the groups. Enhanced oxidative stress in men may provide a biochemical link between male sex and atherosclerotic diseases related to oxidative stress.

Angiotensin II and catecholamines increase plasma levels of 8-epi-prostaglandin F(2alpha) with different pressor dependencies in rats.

We investigated the extent of oxidative stress evoked in the hypertensive rat by measuring plasma levels of 8-epi-prostaglandin F(2alpha) (8-epi-PGF(2alpha)), a marker of in vivo oxidative stress. Administration of angiotensin (Ang) II and norepinephrine at doses of 0.7 and 2.8 mg. kg(-1). d(-1), respectively, resulted in similar significant elevations in plasma levels of 8-epi-PGF(2alpha). A 7-day infusion of Ang II at a nonpressor dose, but not norepinephrine at a nonpressor dose, also increased plasma levels of 8-epi-PGF(2alpha). The norepinephrine-induced increase in 8-epi-PGF(2alpha) levels could be completely normalized by 3 different classes of antihypertensive drugs: prazosin, an alpha-adrenergic receptor blocker; hydralazine, a nonspecific vasodilator; and losartan, a specific angiotensin type 1 (AT(1)) receptor antagonist. This finding suggests that the norepinephrine-induced increase is a pressor-dependent event. In contrast, among these antihypertensive drugs, only losartan was effective in inhibiting the Ang II-induced increase in plasma 8-epi-PGF(2alpha), suggesting that Ang II increases plasma levels of 8-epi-PGF(2alpha) in both a pressor-independent and an AT(1) receptor-dependent manner. In summary, continuous infusion of both Ang II and norepinephrine potently increases plasma levels of 8-epi-PGF(2alpha) and thus in vivo oxidative stress. Ang II and norepinephrine seem to induce this increase in 8-epi-PGF(2alpha) via mechanisms with different pressor dependencies.