24 results on '"Hidenao Kakehashi"'
Search Results
2. Metabolism of N1-cyclopropylmethanoyl-lysergicaciddiethylamide (1cP-LSD) by human liver microsomes
- Author
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Akari Miyake, Hidenao Kakehashi, Noriaki Shima, Tooru Kamata, Munehiro Katagi, and Hiroshi Nishioka
- Subjects
General Medicine - Published
- 2023
3. Automated simultaneous identification of methamphetamine, precursor compounds to methamphetamine and their metabolites in urine for proof of methamphetamine use
- Author
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Shihoko Nakano-Fujii, Tooru Kamata, Hidenao Kakehashi, Hiroe Kamata, Keiko Sasaki, Shuntaro Matsuta, Noriaki Shima, Akihiro Miki, and Munehiro Katagi
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General Medicine - Published
- 2022
4. Application of probe electrospray ionization mass spectrometry to the analysis of poisons and drugs in adulterated foods and beverages
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Akihiro Miki, Ryutaro Asai, Hiroe Kamata, Munehiro Katagi, Atsushi Nitta, Misato Wada, Keiko Sasaki, Tasuku Murata, Shuntaro Matsuta, Koretsugu Ogata, Tooru Kamata, Shihoko Nakano-Fujii, Akari Ishikawa, Hidenao Kakehashi, Hiroshi Nishioka, Noriaki Shima, and Hitoshi Tsuchihashi
- Subjects
Chromatography ,Chemistry ,Electrospray ionization - Published
- 2021
5. Urinary excretion profiles of etizolam and its main metabolites after a single oral dose
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Misato Wada, Noriaki Shima, Tooru Kamata, Shuntaro Matsuta, Akari Ishikawa, Atsushi Nitta, Ryutaro Asai, Hidenao Kakehashi, Shihoko Fujii, Keiko Sasaki, Hiroe Kamata, and Munehiro Katagi
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Single oral dose ,Urinary excretion ,business.industry ,Medicine ,General Medicine ,Etizolam ,Pharmacology ,business ,medicine.drug - Published
- 2021
6. Development of a new method for cyanide determination using dimethoxytriazinyl (DMT) derivatization
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Tooru Kamata, Misato Wada, Noriaki Shima, Shihoko Nakano, Keiko Sasaki, Hiroe Kamata, Akari Ishikawa, Hiroshi Nishioka, Munehiro Katagi, Atsushi Nitta, Hidenao Kakehashi, Ryutaro Asai, Akihiro Miki, and Shuntaro Matsuta
- Subjects
chemistry.chemical_compound ,Chromatography ,chemistry ,Cyanide ,Gas chromatography–mass spectrometry ,Derivatization - Published
- 2020
7. Discrimination between internal and external uses by analysis of urine and blood from diphenhydramine users
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Akari Ishikawa, Hiroshi Nishioka, Misato Wada, Atsushi Nitta, Shihoko Nakano, Hiroe Kamata, Shuntaro Matsuta, Ryutaro Asai, Tooru Kamata, Akihiro Miki, Noriaki Shima, Munehiro Katagi, Keiko Sasaki, and Hidenao Kakehashi
- Subjects
business.industry ,Anesthesia ,Diphenhydramine ,medicine ,Urine ,business ,medicine.drug - Published
- 2020
8. Development of the Exact Mass Database of Surfactants and Its Forensic Application
- Author
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Shihoko Nakano, Noriaki Shima, Toru Kamata, Hitoshi Tsuchihashi, Akihiro Miki, Hiroshi Nishioka, Keiko Sasaki, Shuntaro Matsuta, Munehiro Katagi, Hidenao Kakehashi, and Hiroe Kamata
- Subjects
Mass ,Information retrieval ,Development (topology) ,Computer science - Published
- 2019
9. Human and rat microsomal metabolites of N-tert-butoxycarbonylmethamphetamine and its urinary metabolites in rat
- Author
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Akihiro Miki, Atsushi Nitta, Ryutaro Asai, Hiroshi Nishioka, Hiroe Kamata, Noriaki Shima, Hidenao Kakehashi, Takahiro Doi, Misato Wada, Tooru Kamata, Shuntaro Matsuta, Keiko Sasaki, Shihoko Fujii, Akari Miyake, Munehiro Katagi, and Hiroshi Hasegawa
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Chromatography ,Chemistry ,Biochemistry (medical) ,Urine ,Metabolism ,Toxicology ,Pathology and Forensic Medicine ,Rats ,Body Fluids ,Methamphetamine ,Excretion ,Hydroxylation ,Metabolic pathway ,chemistry.chemical_compound ,Glucuronides ,Microsome ,Microsomes, Liver ,Ingestion ,Humans ,Animals ,Urinary Tract ,Incubation ,Chromatography, Liquid - Abstract
Purpose N-tert-Butoxycarbonylmethamphetamine (BocMA), a masked derivative of methamphetamine (MA), converts into MA under acidic condition and potentially acts as a precursor to MA following ingestion. To investigate the metabolism and excretion of BocMA, metabolism tests were conducted using human liver microsomes (HLM), rat liver microsomes (RLM) and rat. Methods BocMA metabolites were analyzed after 1000-ng/mL BocMA incubation with microsomes for 3, 8, 13, 20, 30, and 60 min. Rats were administered intraperitoneal injections (20 mg/kg) of BocMA and their urine was collected in intervals for 72 h. Metabolites were detected by liquid chromatography–tandem mass spectrometry with five authentic standards. Results Several metabolites including 4-hydroxy-BocMA, N-tert-butoxycarbonylephedrine and N-tert-butoxycarbonyl-cathinone were detected for HLM and RLM. In the administration test, three glucuronides of hydroxylated metabolites were detected. The total recovery values of BocMA and the metabolites during the first 72 h accounted for only 0.3% of the administered dose. Throughout the microsomal and administration experiments, MAs were not detected. Conclusion Hydroxylation, carbonylation and N-demethylation were proposed as metabolic pathways. However, BocMA and phase I metabolites were hardly detected in urine. This study provides useful information to interpret the possibility of BocMA intake as the cause of MA detection in biological sample.
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- 2021
10. Incorporation of Methoxyphenamine into Hair in Early Stage after Intake
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Takako Sato, Ryutaro Asai, Akari Ishikawa, Shihoko Fujii, Hitoshi Tsuchihashi, Shuntaro Matsuta, Misato Wada, Noriaki Shima, Hiroe Kamata, Akihiro Miki, Atsushi Nitta, Hidenao Kakehashi, Keiko Sasaki, Tooru Kamata, Munehiro Katagi, and Hiroshi Nishioka
- Subjects
medicine.medical_specialty ,Health, Toxicology and Mutagenesis ,Urine ,Toxicology ,Analytical Chemistry ,Methamphetamine ,chemistry.chemical_compound ,Black hair ,Dermis ,Oral administration ,Internal medicine ,medicine ,Environmental Chemistry ,Chemical Health and Safety ,integumentary system ,Methoxyphenamine ,Bulb ,Substance Abuse Detection ,Endocrinology ,medicine.anatomical_structure ,Hair root ,chemistry ,medicine.drug ,Chromatography, Liquid ,Hair - Abstract
In order to investigate the incorporation behavior of drugs into hair in early stage (within 24 h) after intake, time-course changes in drug distribution in black hair were carefully analyzed after a single oral administration of methoxyphenamine (MOP), a non-regulated analog of methamphetamine. Single-hair specimens collected by plucking with the roots intact at appropriate intervals post-intake were each divided into 1-mm segments from the proximal end, and MOP in each segment was determined by a validated liquid chromatography–tandem mass spectrometry procedure. At 10 min after intake, MOP was not detected in any of the segments. MOP became detectable 30 min after intake in the hair bulb (0–1-mm segment from the proximal end) and 1 h after intake in the upper dermis zone (1–2-mm to 4–5-mm segments). The amount of MOP in the hair bulb increased rapidly over 3 h after intake and reached a maximum concentration of ∼100–900 pg/1-mm single hair (11–95 ng/mg) around 3–10 h after intake, whereas that in the upper dermis zone increased at a more gradual pace over 24 h and reached a plateau at ∼30–100 pg/1-mm hair (3–11 ng/mg). These differences can be attributed to the different incorporation mechanisms of the drug. Results from this study can further elucidate the drug incorporation mechanism, which is crucial for accurately interpreting results in hair analyses. Our findings also suggest that hair drug analysis with special attention to the hair root can serve as a useful complementary approach to urine- and blood-based testing in the field of forensic toxicology.
- Published
- 2020
11. Dehydration-fragmentation mechanism of cathinones and their metabolites in ESI-CID
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Atsushi Nitta, Yoshio Nishiyama, Ryutaro Asai, Hirohisa Nagatani, Hiroe Kamata, Akari Ishikawa, Shuntaro Matsuta, Misato Wada, Munehiro Katagi, Shihoko Nakano, Hidenao Kakehashi, Hisanori Imura, and Noriaki Shima
- Subjects
Reaction mechanism ,Cathinone ,Tertiary amine ,Electrospray ionization ,Metabolite ,medicine.disease ,Medicinal chemistry ,chemistry.chemical_compound ,chemistry ,medicine ,Amine gas treating ,Rearrangement reaction ,Dehydration ,Spectroscopy ,medicine.drug - Abstract
Various cathinone-derived designer drugs (CATs) have recently appeared on the drug market. This study examined the mechanism for the generation of dehydrated ions for CATs during electrospray ionization collision-induced dissociation (ESI-CID). The generation mechanism of dehydrated ions is dependent on the amine classification in the cathinone skeleton, which is used in the identification of CATs. The two hydrogen atoms eliminated during the dehydration of cathinone (primary amine) and methcathinone (secondary amine) were determined, and the reaction mechanism was elucidated through the deuterium labeling experiments. The hydrogen atom bonded to the amine nitrogen was eliminated with the proton added during ESI, in both of the tested compounds. This provided evidence that CATs with tertiary amine structures (such as dimethylcathinone and α-pyrrolidinophenones [α-PPs]) do not undergo dehydration. However, it was shown that the two major tertiary amine metabolites (1-OH and 2″-oxo) of CATs generate dehydrated ions in ESI-CID. The dehydration mechanisms of the metabolites of α-pyrrolidinobutiophenone (α-PBP) belongs to α-PPs were also investigated. Stable-isotope labeling showed the dehydration of the 1-OH metabolite following a simple mechanism where the hydroxy group was eliminated together with the proton added during ESI. In contrast, the dehydration mechanism of the 2″-oxo metabolite involved hydrogen atoms in three or more locations along with the carbonyl group oxygen, indicating that dehydration occurred via multiple mechanisms likely including the rearrangement reaction of hydrogen atoms. These findings presented herein indicate that the dehydrated ions in ESI-CID can be used for the structural identification of CATs.
- Published
- 2020
12. A new method for detection of nitrous oxide using azo coupling reaction
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Hiroshi Nishioka, Ryutaro Asai, Shihoko Nakano, Hidenao Kakehashi, Tooru Kamata, Shuntaro Matsuta, Misato Wada, Akihiro Miki, Noriaki Shima, Munehiro Katagi, and Atsushi Nitta
- Subjects
chemistry.chemical_compound ,Chemistry ,010401 analytical chemistry ,Inorganic chemistry ,Nitrous oxide ,Azo coupling ,010402 general chemistry ,Photochemistry ,01 natural sciences ,0104 chemical sciences - Published
- 2018
13. Effects of lipophilicity and functional groups of synthetic cannabinoids on their blood concentrations and urinary excretion
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Keiko Sasaki, Misato Wada, Shuntaro Matsuta, Atsushi Nitta, Akihiro Miki, Ryutaro Asai, Hiroe Kamata, Hiroshi Nishioka, Munehiro Katagi, Noriaki Shima, Tooru Kamata, Shihoko Nakano, Hidenao Kakehashi, and Akari Ishikawa
- Subjects
Octanol ,Octanols ,Chromatography ,medicine.drug_class ,Cannabinoids ,Water ,Carboxamide ,Urine ,Pathology and Forensic Medicine ,Partition coefficient ,chemistry.chemical_compound ,Pharmacokinetics ,chemistry ,Valine ,Tandem Mass Spectrometry ,Lipophilicity ,Synthetic cannabinoids ,medicine ,Humans ,Law ,medicine.drug ,Chromatography, Liquid - Abstract
The influence of lipophilicity and functional groups of synthetic cannabinoids (SCs) on their blood concentrations and urinary excretion has been studied by analyzing blood and urine specimens sampled from drivers who were involved in a car crashes under the influence of SCs. A total of 58 specimens (26 urine and 31 blood specimens), sampled within 13h of the occurrence, were analyzed by liquid chromatography-tandem mass spectrometry. Fifteen SCs were detected in those specimens; the SCs detected were categorized as follows: Class 1, Naphthoyl/Benzoyl indole (EAM2201 and three other analogs); Class 2, Indole-3-carboxylate/carboxamide containing naphthol/quinol (5F-PB-22 and four other analogs); and Class 3, Indazole-3-carboxamide containing valine/tert-leucine derivative (5F-AMB and five other analogs). The calculated lipophilicity index log P, the octanol/water participation coefficient, of those SCs in Classes 1, 2, and 3 ranged between 5.01-8.14, 5.80-6.74 and 2.29-3.81, respectively. Class 3 SCs were detectable in 12 out of 13 urine specimens, but those in Classes 1 and 2 were not detected in urine. Our analytical results indicated that the boundary line for their detectability in urine lies between log P 4 and 5. The blood concentrations of Class 3 SCs varied widely (0.0036-31ng/ml) depending on their log P, while much smaller variation was observed among those in Class 2 (0.10-5.0ng/ml).
- Published
- 2019
14. Incorporation of zolpidem and methoxyphenamine into white hair strands after single administrations: Influence of hair pigmentation on drug incorporation
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Shuntaro Matsuta, Ryutaro Asai, Shihoko Nakano, Noriaki Shima, Tooru Kamata, Hiroe Kamata, Akihiro Miki, Atsushi Nitta, Hitoshi Tsuchihashi, Akari Ishikawa, Hidenao Kakehashi, Misato Wada, Takako Sato, Munehiro Katagi, and Keiko Sasaki
- Subjects
Drug ,Male ,Narcotics ,medicine.medical_specialty ,Zolpidem ,Time Factors ,media_common.quotation_subject ,01 natural sciences ,Pathology and Forensic Medicine ,Methamphetamine ,03 medical and health sciences ,chemistry.chemical_compound ,Forensic Toxicology ,0302 clinical medicine ,Dermis ,Tandem Mass Spectrometry ,Internal medicine ,otorhinolaryngologic diseases ,medicine ,Humans ,Hypnotics and Sedatives ,030216 legal & forensic medicine ,Hair Color ,media_common ,integumentary system ,Methoxyphenamine ,Chemistry ,010401 analytical chemistry ,Hair analysis ,Middle Aged ,Mass spectrometric ,0104 chemical sciences ,White (mutation) ,Substance Abuse Detection ,Endocrinology ,medicine.anatomical_structure ,Hair root ,sense organs ,Law ,medicine.drug ,Chromatography, Liquid ,Hair - Abstract
In order to investigate the influence of pigmentation on the incorporation of drugs into hair, time-course changes in drug distribution along non-pigmented (white) hairs as well as pigmented (black) hairs plucked from the same subject was observed following single administrations of two basic drugs with different properties, zolpidem and methoxyphenamine. These drugs in 1-mm sections of single hair specimens were each determined by a liquid chromatography–tandem mass spectrometric procedure. During the early stage (12–36 h) after intake, for black hairs, both drugs were detected over the entire area of hair root (4–5 mm in length), in which notable concentration of these drugs in the hair bulb (0–1-mm segment from the bottom of hair root, Region 1) and lower concentrations in the upper dermis zone (1–2-mm to 3–4-mm or to 4–5-mm segments, Region 2) were commonly observed. Meanwhile, for white hairs, high drug concentrations in Region 1 as detected in black hairs were not observed although only small amounts of these drugs were detected over Region 2. Subsequent time-course changes in the concentration of drugs in hair demonstrated that the drugs once incorporated into white hair via Region 2 decreased gradually over the period from 24 h to 35 days after intake, but those of black hairs remained almost unchanged. These findings revealed here suggest that hair pigments have two important roles in the distribution of drugs: (1) incorporation of drugs into hair via Region 1, and (2) retention of already incorporated drugs in the hair tissue. These findings would be useful for discussing individual drug-use history based on hair analysis in the forensic fields.
- Published
- 2019
15. Urinary excretion and metabolism of the α-pyrrolidinophenone designer drug 1-phenyl-2-(pyrrolidin-1-yl)octan-1-one (PV9) in humans
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Keiko Sasaki, Shihoko Nakano, Kei Zaitsu, Hitoshi Tsuchihashi, Munehiro Katagi, Hiroshi Nishioka, Noriaki Shima, Akihiro Miki, Hidenao Kakehashi, Tooru Kamata, Hiroe Kamata, Takako Sato, and Shuntaro Matsuta
- Subjects
chemistry.chemical_classification ,Ketone ,Stereochemistry ,Biochemistry (medical) ,Diastereomer ,Alcohol ,Toxicology ,Tandem mass spectrometry ,Pyrrolidine ,Pathology and Forensic Medicine ,Hydroxylation ,Metabolic pathway ,chemistry.chemical_compound ,chemistry ,Carboxylate - Abstract
1-Phenyl-2-(pyrrolidin-1-yl)octan-1-one (PV9) and 16 metabolites, including diastereomers and conjugates, were identified or tentatively detected in human urine by gas chromatography–mass spectrometry and liquid chromatography–high-resolution tandem mass spectrometry. These urinary metabolites indicated that the metabolic pathways of PV9 include: (1) the reduction of ketone groups to their corresponding alcohols; (2) oxidation of the pyrrolidine ring to the corresponding pyrrolidone; (3) aliphatic oxidation of the terminal carbon atom to the corresponding carboxylate form, possibly through an alcohol intermediate (not detected); and (4) hydroxylation at the penultimate carbon atom to the corresponding alcohols followed by further oxidation to ketones, and combinations of these steps. In addition, results from the quantitative analyses of five phase-I metabolites using newly synthesized authentic standards suggested that the main metabolic pathway includes the aliphatic oxidation of terminal and/or penultimate carbons. Human metabolism of PV9 differed significantly from those of α-pyrrolidinovalerophenone and α-pyrrolidinobutiophenone, suggesting that the main metabolic pathways of α-pyrrolidinophenones significantly change depending on the alkyl chain length of the parent molecule.
- Published
- 2015
16. Dehydration-fragmentation mechanism of cathinones and their metabolites in ESI-CID.
- Author
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Shuntaro Matsuta, Noriaki Shima, Hidenao Kakehashi, Akari Ishikawa, Ryutaro Asai, Atsushi Nitta, Misato Wada, Shihoko Nakano, Hiroe Kamata, Yoshio Nishiyama, Hirohisa Nagatani, Hisanori Imura, and Munehiro Katagi
- Subjects
DEHYDRATION reactions ,HYDROGEN atom ,DESIGNER drugs ,REARRANGEMENTS (Chemistry) ,SECONDARY amines ,CARBONYL group ,TERTIARY amines - Abstract
Various cathinone-derived designer drugs (CATs) have recently appeared on the drug market. This study examined the mechanism for the generation of dehydrated ions for CATs during electrospray ionization collision-induced dissociation (ESI-CID). The generation mechanism of dehydrated ions is dependent on the amine classification in the cathinone skeleton, which is used in the identification of CATs. The two hydrogen atoms eliminated during the dehydration of cathinone (primary amine) and methcathinone (secondary amine) were determined, and the reaction mechanism was elucidated through the deuterium labeling experiments. The hydrogen atom bonded to the amine nitrogen was eliminated with the proton added during ESI, in both of the tested compounds. This provided evidence that CATs with tertiary amine structures (such as dimethylcathinone and α-pyrrolidinophenones [α-PPs]) do not undergo dehydration. However, it was shown that the two major tertiary amine metabolites (1-OH and 2”-oxo) of CATs generate dehydrated ions in ESI-CID. The dehydration mechanisms of the metabolites of α-pyrrolidinobutiophenone (α-PBP) belongs to α-PPs were also investigated. Stable-isotope labeling showed the dehydration of the 1-OH metabolite following a simple mechanism where the hydroxy group was eliminated together with the proton added during ESI. In contrast, the dehydration mechanism of the 2”-oxo metabolite involved hydrogen atoms in three or more locations along with the carbonyl group oxygen, indicating that dehydration occurred via multiple mechanisms likely including the rearrangement reaction of hydrogen atoms. These findings presented herein indicate that the dehydrated ions in ESI-CID can be used for the structural identification of CATs. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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17. Critical contribution of oxidative stress to TNFα-induced necroptosis downstream of RIPK1 activation
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Ko Okumura, Yoshito Kumagai, Hidenao Kakehashi, Ryodai Shindo, and Hiroyasu Nakano
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Programmed cell death ,Indoles ,Cell Survival ,Necroptosis ,Blotting, Western ,Biophysics ,Butylated Hydroxyanisole ,Apoptosis ,Models, Biological ,Biochemistry ,Antioxidants ,Fas ligand ,Inhibitor of Apoptosis Proteins ,Mice ,Necrosis ,RIPK1 ,Animals ,FADD ,Phosphorylation ,Molecular Biology ,Cells, Cultured ,Death domain ,Mice, Knockout ,Dose-Response Relationship, Drug ,biology ,Tumor Necrosis Factor-alpha ,Imidazoles ,Transcription Factor RelA ,Cell Biology ,Fibroblasts ,Embryo, Mammalian ,TRADD ,Cell biology ,Enzyme Activation ,Oxidative Stress ,Receptor-Interacting Protein Serine-Threonine Kinases ,Cancer research ,biology.protein ,Reactive Oxygen Species - Abstract
While apoptosis has been considered to be identical to programmed cell death, necroptosis, which is morphologically related to necrosis, has emerged as a novel type of programmed cell death. Necroptosis depends on two structurally related kinases, receptor-interacting serine-threonine kinase (RIPK)1 and RIPK3. RIPK1 is activated through oligomerization of upstream adaptor molecules such as Fas-associated protein with death domain (FADD) and TNF receptor-associated death domain (TRADD) that are triggered by TNFα or Fas ligand. Activated RIPK1 subsequently interacts with and activates RIPK3, resulting in necroptosis. However, contribution of oxidative stress to execution of necroptosis is still controversial. We found that a selective inhibitor for RIPK1, necrostatin-1 (Nec-1) significantly blocked TNFα-induced cell death and ROS accumulation in NF-κB activation-deficient cells. This suggests that these cells mostly died by necroptosis upon TNFα stimulation. Intriguingly, an antioxidant, butylated hydroxyanisole (BHA) blocked TNFα-induced necroptosis and ROS accumulation in NF-κB activation-deficient cells. However, Nec-1, but not BHA, inhibited TNFα-induced phosphorylation of RIPK1 in these cells, suggesting that ROS play a crucial role in execution of necroptosis downstream of RIPK1 activation. Structural and functional analyses using BHA related compounds revealed that both tert-butyl and hydroxy groups of BHA are crucial for its anti-necroptotic function. Together, these results suggest that TNFα-induced necroptosis is tightly associated with oxidative stress, and oxidative stress is induced downstream of RIPK1 activation.
- Published
- 2013
18. Reactive Sulfur Species-Mediated Activation of the Keap1-Nrf2 Pathway by 1,2-Naphthoquinone through Sulfenic Acids Formation under Oxidative Stress
- Author
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Takaaki Akaike, Hidenao Kakehashi, Yoshito Kumagai, Isao Ishii, Tomoaki Ida, Motohiro Nishida, Yumi Abiko, Takashi Miura, Yasuhiro Shinkai, and Tomohiro Sawa
- Subjects
NF-E2-Related Factor 2 ,Sulfur metabolism ,chemistry.chemical_element ,Disproportionation ,Naphthols ,Toxicology ,Photochemistry ,medicine.disease_cause ,Sulfenic Acids ,chemistry.chemical_compound ,Cell Line, Tumor ,medicine ,Humans ,Cysteine ,Sulfhydryl Compounds ,chemistry.chemical_classification ,Reactive oxygen species ,Kelch-Like ECH-Associated Protein 1 ,Intracellular Signaling Peptides and Proteins ,General Medicine ,Glutathione ,Sulfur ,Oxidative Stress ,chemistry ,Electrophile ,Sulfenic acid ,Oxidative stress ,Naphthoquinones ,Signal Transduction - Abstract
Sulfhydration by a hydrogen sulfide anion and electrophile thiolation by reactive sulfur species (RSS) such as persulfides/polysulfides (e.g., R-S-SH/R-S-Sn-H(R)) are unique reactions in electrophilic signaling. Using 1,2-dihydroxynaphthalene-4-thioacetate (1,2-NQH2-SAc) as a precursor to 1,2-dihydroxynaphthalene-4-thiol (1,2-NQH2-SH) and a generator of reactive oxygen species (ROS), we demonstrate that protein thiols can be modified by a reactive sulfenic acid to form disulfide adducts that undergo rapid cleavage in the presence of glutathione (GSH). As expected, 1,2-NQH2-SAc is rapidly hydrolyzed and partially oxidized to yield 1,2-NQ-SH, resulting in a redox cycling reaction that produces ROS through a chemical disproportionation reaction. The sulfenic acid forms of 1,2-NQ-SH and 1,2-NQH2-SH were detected by derivatization experiments with dimedone. 1,2-NQH2-SOH modified Keap1 at Cys171 to produce a Keap1-S-S-1,2-NQH2 adduct. Subsequent exposure of A431 cells to 1,2-NQ or 1,2-NQH2-SAc caused an extensive chemical modification of cellular proteins in both cases. Protein adduction by 1,2-NQ through a thio ether (C-S-C) bond slowly declined through a GSH-dependent S-transarylation reaction, whereas that originating from 1,2-NQH2-SAc through a disulfide (C-S-S-C) bond was rapidly restored to the free protein thiol in the cells. Under these conditions, 1,2-NQH2-SAc activated Nrf2 and upregulated its target genes, which were enhanced by pretreatment with buthionine sulfoximine (BSO), to deplete cellular GSH. Pretreatment of catalase conjugated with poly(ethylene glycol) suppressed Nrf2 activation by 1,2-NQH2-SAc. These results suggest that RSS-mediated reversible electrophilic signaling takes place through sulfenic acids formation under oxidative stress.
- Published
- 2015
19. Metabolism of the designer drug α-pyrrolidinobutiophenone (α-PBP) in humans: identification and quantification of the phase I metabolites in urine
- Author
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Takako Sato, Shuntaro Matsuta, Munehiro Katagi, Kei Zaitsu, Hidenao Kakehashi, Akihiro Miki, Hitoshi Tsuchihashi, Hiroe Kamata, Noriaki Shima, Shihoko Nakano, Keiko Sasaki, Tooru Kamata, Koichi Suzuki, and Hiroshi Nishioka
- Subjects
chemistry.chemical_classification ,Propiophenones ,Chromatography ,Ketone ,Pyrrolidines ,medicine.drug_class ,Diastereomer ,Pyrrolidine ,Gas Chromatography-Mass Spectrometry ,Pathology and Forensic Medicine ,Designer Drugs ,Designer drug ,chemistry.chemical_compound ,Metabolic pathway ,chemistry ,Tandem Mass Spectrometry ,medicine ,Humans ,Gas chromatography–mass spectrometry ,Glucuronide ,Law ,Drug metabolism ,Chromatography, Liquid - Abstract
Urinary phase I metabolites of α-pyrrolidinobutiophenone (α-PBP) in humans were investigated by analyzing urine specimens obtained from drug abusers. Unequivocal identification and accurate quantification of major metabolites were realized using gas chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry with newly synthesized authentic standards. Two major phase I metabolic pathways were revealed: (1) reduction of the ketone group to 1-phenyl-2-(pyrrolidin-1-yl)butan-1-ol (OH-α-PBP, diastereomers) partly followed by conjugation to its glucuronide and (2) oxidation at the 2″-position of the pyrrolidine ring to α-(2″-oxo-pyrrolidino)butiophenone (2″-oxo-α-PBP) via the putative intermediate α-(2″-hydroxypyrrolidino)butiophenone (2″-OH-α-PBP). Of the phase I metabolites retaining the structural characteristics of the parent drug, OH-α-PBP was the most abundant in all specimens examined. Comparison of the phase I metabolism of α-PBP and α-pyrrolidinovalerophenone (α-PVP) suggested a relationship between the aliphatic side chain length and the metabolic pathways in α-pyrrolidinophenones: the shorter aliphatic side chain (1) led to more extensive metabolism via reduction of the ketone group than via the oxidation at the 2″-position of the pyrrolidine ring and (2) influenced the isomeric ratio of a pair of diastereomers.
- Published
- 2014
20. Glutathione-mediated reversibility of covalent modification of ubiquitin carboxyl-terminal hydrolase L1 by 1,2-naphthoquinone through Cys152, but not Lys4
- Author
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Toshiyuki Kaji, Yasuhiro Shinkai, Yoshito Kumagai, Takashi Toyama, Aki Yazawa, and Hidenao Kakehashi
- Subjects
Blotting, Western ,Dehydrogenase ,Toxicology ,chemistry.chemical_compound ,Ubiquitin ,Cell Line, Tumor ,Hydrolase ,Humans ,Buthionine sulfoximine ,Electrophoresis, Gel, Two-Dimensional ,Cysteine ,Glyceraldehyde 3-phosphate dehydrogenase ,chemistry.chemical_classification ,biology ,Lysine ,Ubiquitination ,General Medicine ,Glutathione ,Recombinant Proteins ,Enzyme ,chemistry ,Biochemistry ,Covalent bond ,biology.protein ,Ubiquitin Thiolesterase ,Naphthoquinones - Abstract
Covalent modification of cellular proteins by electrophiles affects electrophilic signal transduction and the dysfunction of enzymes that is involved in cytotoxicity. We have recently found a unique reaction which restores glyceraldehyde-3-phosphate dehydrogenase (GAPDH) that has been modified by 1,2-naphthoquinone (1,2-NQ) through a glutathione (GSH)-dependent S-transarylation reaction. We report here that ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) undergoes the same reaction. Exposure of human neuroblastoma SH-SY5Y cells to 1,2-NQ after pretreatment with buthionine sulfoximine (BSO) to deplete GSH resulted in an enhancement of covalent modification of UCH-L1 by 1,2-NQ. With recombinant human UCH-L1, we demonstrated that UCH-L1 underwent arylation by 1,2-NQ through Cys152 and Lys4, thereby decreasing its catalytic activity. Addition of GSH to an incubation mixture of 1,2-NQ-UCH-L1 adduct partially restored this decline in enzyme activity which was accompanied by decreased covalent attachment of 1,2-NQ, together with production of 1,2-NQ-GSH adduct. UCH-L1 in which Lys4 was mutated exhibited a lower level of covalent modification and enzyme inhibition, but completely recovered after addition of GSH. Taken together, these results suggest that Cys152 modification in UCH-L1 by 1,2-NQ is reversible via GSH-mediated S-transarylation reaction whereas Lys4 modification by 1,2-NQ is irreversible by GSH. Because UCH-L1 dysfunction has been associated with neurodegeneration, the electrophilic modification of Lys rather than Cys in UCH-L1 may be implicated in such neurodegenerative diseases.
- Published
- 2013
21. GSH-mediated S-transarylation of a quinone glyceraldehyde-3-phosphate dehydrogenase conjugate
- Author
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Yuko Egara, Takashi Miura, Arthur K. Cho, Yasuhiro Shinkai, Yoshito Kumagai, Hidenao Kakehashi, and Reiko Hirose
- Subjects
Protein Denaturation ,Dehydrogenase ,Toxicology ,Cell Line ,chemistry.chemical_compound ,stomatognathic system ,Escherichia coli ,Humans ,Buthionine sulfoximine ,Sulfhydryl Compounds ,Cloning, Molecular ,Buthionine Sulfoximine ,Glyceraldehyde 3-phosphate dehydrogenase ,A549 cell ,biology ,Cell-Free System ,Chemistry ,Glyceraldehyde-3-Phosphate Dehydrogenases ,Epithelial Cells ,General Medicine ,Glutathione ,Recombinant Proteins ,Quinone ,Biochemistry ,Covalent bond ,Mutation ,biology.protein ,Transformation, Bacterial ,Glycolysis ,Oxidation-Reduction ,Protein Processing, Post-Translational ,Conjugate ,Naphthoquinones ,Plasmids - Abstract
Many cellular proteins with reactive thiols form covalent bonds with electrophiles, thereby modifying their structures and activities. Here, we describe the recovery of a glycolytic protein, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), from such an electrophilic attack by 1,2-napthoquinone (1,2-NQ). GAPDH readily formed a covalent bond with 1,2-NQ through Cys152 at a low concentration (0.2 μM) in a cell-free system, but when human epithelial A549 cells were exposed to this quinone at 20 μM, only minimal binding was observed although extensive binding to numerous other cellular proteins occurred. Depletion of cellular glutathione (GSH) with buthionine sulfoximine (BSO) resulted in some covalent modification of cellular GAPDH by 1,2-NQ and a significant reduction of GAPDH activity in the cells. Incubation of native, but not boiled, human GAPDH that had been modified by 1,2-NQ with GSH resulted in a concentration-dependent removal of 1,2-NQ from the GAPDH conjugate, accompanied by partial recovery of lost catalytic activity and formation of a 1,2-NQ-GSH adduct (1,2-NQ-SG). While GAPDH is recognized as a multifunctional protein, our results show that GAPDH also has a unique ability to recover from electrophilic modification by 1,2-NQ through a GSH-dependent S-transarylation reaction.
- Published
- 2011
22. Reactive Sulfur Species-MediatedActivation of theKeap1–Nrf2 Pathway by 1,2-Naphthoquinone through Sulfenic AcidsFormation under Oxidative Stress.
- Author
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Yasuhiro Shinkai, Yumi Abiko, Tomoaki Ida, Takashi Miura, Hidenao Kakehashi, Isao Ishii, Motohiro Nishida, Tomohiro Sawa, Takaaki Akaike, and Yoshito Kumagai
- Published
- 2015
- Full Text
- View/download PDF
23. GSH-Mediated S-Transarylation of a Quinone Glyceraldehyde-3- Phosphate Dehydrogenase Conjugate.
- Author
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Takashi Miura, Hidenao Kakehashi, Yasuhiro Shinkai, Yuko Egara, Reiko Hirose, Cho, Arthur K, and Yoshito Kumagai
- Subjects
- *
GLYCERALDEHYDEPHOSPHATE dehydrogenase , *THIOLS , *COVALENT bonds , *ELECTROPHILES , *GLUTATHIONE , *PROTEIN binding - Abstract
Many cellular proteins with reactive thiols form covalent bonds with electrophiles, thereby modifying their structures and activities. Here, we describe the recovery of a glycolytic protein, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), from such an electrophilic attack by 1,2-napthoqui-none (1,2-NQ). GAPDH readily formed a covalent bond with 1,2-NQ through Cysl52 at a low concentration (0.2 µM) in a cell-free system, but when human epithelial A549 cells were exposed to this quinone at 20 µM, only minimal binding was observed although extensive bfoding to numerous other cellular proteins occurred. Depletion of cellular glutathione (GSH) with butbionine sulfoximine (BSO) resulted in some covalent modification of cellular GAPDH by 1,2-NQ and a significant reduction of GAPDH activity in the cells. Incubation of native, but not boiled, human GAPDH that had been modified by 1,2-NQ with GSH resulted in a concentration-dependent removal of 1,2-NQ from the GAPDH conjugate, accompanied by partial recovery of lost catalytic activity and formation of a 1,2-NQ;GSH adduct (1,2-NQSG). While GAPDH is recognized as a multifunctional protein, our results show that GAPDH also has a unique ability to recover from electrophilic modification by 1,2-NQthrough a GSH-dependent S-transarylation reaction. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
24. Metabolism of the designer drug α-pyrrolidinobutiophenone (α-PBP) in humans: Identification and quantification of the phase I metabolites in urine.
- Author
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Shuntaro Matsuta, Noriaki Shima, Hiroe Kamata, Hidenao Kakehashi, Shihoko Nakano, Keiko Sasaki, Tooru Kamata, Hiroshi Nishioka, Akihiro Miki, Munehiro Katagi, Kei Zaitsu, Takako Sato, Hitoshi Tsuchihashi, and Koichi Suzuki
- Subjects
- *
DESIGNER drugs , *STIMULANTS , *DRUG metabolism , *URINALYSIS , *GAS chromatography/Mass spectrometry (GC-MS) , *KETONES - Abstract
Urinary phase I metabolites of α-pyrrolidinobutiophenone (α-PBP) in humans were investigated by analyzing urine specimens obtained from drug abusers. Unequivocal identification and accurate quantification of major metabolites were realized using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry with newly synthesized authentic standards. Two major phase I metabolic pathways were revealed: (1) reduction of the ketone group to 1-phenyl-2-(pyrrolidin-1-yl)butan-1-ol (OH-α-PBP, diastereomers) partly followed by conjugation to its glucuronide and (2) oxidation at the 200-position of the pyrrolidine ring to α-(200-oxo-pyrrolidino)butiophenone (200-oxo-α-PBP) via the putative intermediate α-(200-hydroxypyrrolidino)butiophenone (200-OH-α-PBP). Of the phase I metabolites retaining the structural characteristics of the parent drug, OH-α-PBP was the most abundant in all specimens examined. Comparison of the phase I metabolism of α-PBP and α-pyrrolidinovalerophenone (α-PVP) suggested a relationship between the aliphatic side chain length and the metabolic pathways in apyrrolidinophenones: the shorter aliphatic side chain (1) led to more extensive metabolism via reduction of the ketone group than via the oxidation at the 200-position of the pyrrolidine ring and (2) influenced the isomeric ratio of a pair of diastereomers. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
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