1
|
Cao L, Miao Y, Liu Y, Huang S, Tian L, Yu M, Huo J, Zhang L, Li X, Chen J. Genotoxic mode of action and threshold exploration of 2-methyl furan under 120-day sub-chronic exposure in male Sprague-Dawley rats. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 273:116125. [PMID: 38394755 DOI: 10.1016/j.ecoenv.2024.116125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/15/2024] [Accepted: 02/18/2024] [Indexed: 02/25/2024]
Abstract
2-Methylfuran (2-MF) is an important member of the furan family generated during food thermal processing. An in-vivo multiple endpoint genotoxicity assessment system was applied to explore the genotoxic mode of action and threshold of 2-MF. Male Sprague-Dawley rats received 2-MF by oral gavage at doses of 0.16, 0.625, 2.5, and 10 mg/kg.bw/day for 120 days. An additional 15 days were granted for recovery. The Pig-a gene mutation frequency of RET and RBC showed significant increases among the 2-MF groups on day 120. After a 15-day recovery period, the Pig-a gene mutation frequency returned to levels similar to those in the vehicle control. The tail intensity (TI) values of peripheral blood cells at a dose of 10 mg/kg.bw/day significantly increased from day 4 and remained at a high level after the recovery period. No statistical difference was found in the micronucleus frequency of peripheral blood between any 2-MF dose group and the corn oil group at any timepoint. 2-MF may not induce the production of micronuclei, but it could cause DNA breakage. It could not be ruled out that 2-MF may accumulate in vivo and cause gene mutations. Hence, DNA, other than the spindle, may be directly targeted. The mode of action of 2-MF may be that it was metabolized by EPHX1 to more DNA-active metabolites, thus leading to oxidative and direct DNA damage. The point of departure (PoD) of 2-MF-induced genotoxicity was derived as 0.506 mg/kg bw/day.
Collapse
Affiliation(s)
- Li Cao
- Department of Nutrition and Food Safety, West China School of Public Health/West China Fourth Hospital, Sichuan Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment, Sichuan University, Chengdu, Sichuan 610041, China
| | - Yeqiu Miao
- Department of Nutrition and Food Safety, West China School of Public Health/West China Fourth Hospital, Sichuan Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment, Sichuan University, Chengdu, Sichuan 610041, China
| | - Yufei Liu
- Department of Nutrition and Food Safety, West China School of Public Health/West China Fourth Hospital, Sichuan Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment, Sichuan University, Chengdu, Sichuan 610041, China
| | - Shuzhen Huang
- Department of Nutrition and Food Safety, West China School of Public Health/West China Fourth Hospital, Sichuan Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment, Sichuan University, Chengdu, Sichuan 610041, China
| | - Luojia Tian
- Department of Nutrition and Food Safety, West China School of Public Health/West China Fourth Hospital, Sichuan Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment, Sichuan University, Chengdu, Sichuan 610041, China
| | - Mengqi Yu
- Department of Nutrition and Food Safety, West China School of Public Health/West China Fourth Hospital, Sichuan Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment, Sichuan University, Chengdu, Sichuan 610041, China
| | - Jiao Huo
- Department of Nutrition and Food Safety, Chongqing Center for Disease Control and Prevention, Chongqing 400042, China
| | - Lishi Zhang
- Department of Nutrition and Food Safety, West China School of Public Health/West China Fourth Hospital, Sichuan Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment, Sichuan University, Chengdu, Sichuan 610041, China
| | - Xiaomeng Li
- Department of Nutrition and Food Safety, West China School of Public Health/West China Fourth Hospital, Sichuan Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment, Sichuan University, Chengdu, Sichuan 610041, China.
| | - Jinyao Chen
- Department of Nutrition and Food Safety, West China School of Public Health/West China Fourth Hospital, Sichuan Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment, Sichuan University, Chengdu, Sichuan 610041, China.
| |
Collapse
|
2
|
Bejarano CA, Díaz JE, Cifuentes-López A, López LV, Jaramillo-Gómez LM, Buendia-Atencio C, Lorett Velásquez VP, Mejía SM, Loaiza AE. Experimental and theoretical study of the mechanism and rate constants of the sequential 5- exo-trig spirocyclization involving vinyl, aryl and N-alkoxyaminyl radicals. Org Biomol Chem 2022; 20:4141-4154. [PMID: 35521783 DOI: 10.1039/d2ob00387b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this research the sequential generation and cyclization of N-alkoxyaminyl radicals to produce 1-azaspiro[4.4]nonane, a prominent scaffold in organic and medicinal chemistry, was studied. Competition experiments in benzene at 80 °C with brominated oxime ethers using Bu3SnH as chain transfer and AIBN as the initiator generated vinyl or aryl radicals which were captured by oxime ethers, allowing approximate 5-exo-trig cyclization constants at 4.6 × 108 s-1 and 9.9 × 108 s-1 respectively to be established. Similar results were obtained by kinetic studies using the transition state theory (TST) from ab initio calculations with density functional theory (DFT) using the M06-2X, B3LYP, mPW1PW91 and TPSSh functionals in combination with the 6-311+G(d, p) basis set. Additionally, it was found that the 5-exo-trig cyclization of the N-alkoxyaminyl radical onto CC double bonds is a reversible process whose constants were determined to be in the range of 6.2 × 100 s-1 and 3.5 × 106 s-1 at 80 °C, depending on the nature of the substituents. The calculation of the radical stabilization energy (RSE) shows that the N-alkoxyaminyl radical is a very stable species and its reactivity in the addition on alkenes is governed by its nucleophilic character and the stability of the carbon-centered radical formed after cyclization. The reduction constant of the N-alkoxyaminyl radical with Bu3SnH in the gas phase at 80 °C was also estimated to be 3.4 × 100 M-1 s-1 through computational calculations. This information facilitates the rational planning of cascades and other methodologies applied to the construction of carbocyclic and aza-heterocyclic compounds.
Collapse
Affiliation(s)
- Carlos A Bejarano
- Departamento de Química, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 11001000, Colombia. .,Departamento de Química, Facultad de Ciencias, Universidad Antonio Nariño, Bogotá 110231, Colombia
| | - John E Díaz
- Departamento de Química, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 11001000, Colombia.
| | | | - Lina V López
- Departamento de Química, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 11001000, Colombia.
| | - Luz M Jaramillo-Gómez
- Departamento de Química, Facultad de Ciencias, Universidad del Valle, Cali 760032, Colombia
| | - Cristian Buendia-Atencio
- Departamento de Química, Facultad de Ciencias, Universidad Antonio Nariño, Bogotá 110231, Colombia
| | | | - Sol M Mejía
- Departamento de Química, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 11001000, Colombia.
| | - Alix E Loaiza
- Departamento de Química, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 11001000, Colombia.
| |
Collapse
|