Ascorbic acid, also referred to as vitamin C(Vc), is an important nutrient found in fruits and vegetables that promotes produce quality and human health. Rosa roxburghii is an underutilized natural fruit that contains...Ascorbic acid, also referred to as vitamin C(Vc), is an important nutrient found in fruits and vegetables that promotes produce quality and human health. Rosa roxburghii is an underutilized natural fruit that contains very high levels of Vc. However, the Vc content of R. roxburghii varies considerably during plant development and ripening. To better understand the molecular mechanisms that underlie fluctuations in Vc content of R. roxburghii fruit at different developmental stages, we performed transcriptomic and metabolomic analyses and identified two significant gene networks/modules and 168 transcription factors directly involved in Vc synthesis. Promoter analysis of two core genes involved in Vc synthesis, RrGGP and RrGalUR, revealed the presence of a retroviral long terminal repeat(LTR) insert in the RrGalUR promoter. Using yeast one-hybrid and dual-luciferase assays, we demonstrated that the transcription factors RrHY5H and RrZIP9 bind to the promoter of RrGGP to promote its expression. RrZIP6 and RrWRKY4 bind to the LTR in the RrGalUR promoter to promote its expression. Our results reveal a molecular mechanism that controls Vc synthesis and accumulation in R. roxburghii fruit.展开更多
BACKGROUND High-dose vitamin C treatment(HVCT)can reduce the adverse effect of chemotherapy and enhance the effect of antitumor therapy,which has been considered one of the safest alternative treatments.However,the se...BACKGROUND High-dose vitamin C treatment(HVCT)can reduce the adverse effect of chemotherapy and enhance the effect of antitumor therapy,which has been considered one of the safest alternative treatments.However,the severity of its adverse effects may have been underestimated.The most serious adverse effect is hemolysis,which may result in acute kidney injury or death.Although glucose-6-phosphate dehydrogenase(G6PD)deficiency is considered to be the main cause,the probability and pathological mechanism are not completely understood,leading to a lack of effective and standardized treatment methods.CASE SUMMARY Two patients with colorectal cancer developed hemolytic anemia after using 1 g/kg HVCT.In contrast to previous cases,the lowest hemoglobin level in the two cases was<50 g/L,which was lower than previously reported.This may be because Case 1 had chronic hepatitis B for many years,which caused abnormal liver reserve function,and Case 2 had grade II bone marrow suppression.Both patients improved and were discharged after blood replacement therapy.Our cases had the most severe degree of hemolysis but the best prognosis,suggesting that our treatment may be helpful for rescue of drug-induced hemolysis.This is the first review of the literature on hemolysis caused by HVCT,and we found that all patients with G6PD deficiency developed hemolysis after HVCT.CONCLUSION G6PD deficiency should be considered as a contraindication to HVCT,and it is not recommended for patients with bone marrow suppression,moderate-tosevere anemia,hematopoietic abnormalities,or abnormal liver and kidney function.Early blood purification and steroid therapy may avoid acute kidney injury or death caused by HVCT-related hemolytic anemia.展开更多
Mental disorders seriously affect people’s health and social stability.This Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D...Mental disorders seriously affect people’s health and social stability.This Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D(25(OH)D)levels and mental disorders.The data used for the MR analysis were derived from the summary genome-wide association studies(GWAS)database for VC and 25(OH)D and from the Finn Gen consortium for fourteen mental disorders.Based on the inverse variance weighted(IVW)method,we found a potential causal association between circulating VC and anxiety disorders(IVW:OR=1.139,95%CI:1.023-1.269,P=0.018).However,no causal association was found between VC or 25(OH)D and other mental disorders(P>0.05).In the reverse MR analysis,individuals with Alzheimer’s disease was causally associated with higher concentrations of circulating VC(P=0.012),while individuals with anxiety disorders had a negative association between the concentrations of 25(OH)D(P=0.012).However,the current evidence does not support a causal relationship between VC or 25(OH)D and other mental disorders.In addition,there was no causal association between circulating VC and 25(OH)D(P>0.05).Future studies are needed to confirm these findings and to elucidate the mechanisms of potential causality.展开更多
Time-resolved electron spin resonance has been used to study quenching reactions between the antioxidant Vitamin C （VC） and the triplet excited states of 9,10-phenanthrenequinone （PAQ） in ethylene glycol-water （E...Time-resolved electron spin resonance has been used to study quenching reactions between the antioxidant Vitamin C （VC） and the triplet excited states of 9,10-phenanthrenequinone （PAQ） in ethylene glycol-water （EG-H2O） homogeneous and inhomogeneous reversed micelle solutions. Reversed micelle solutions were used to be the models of physiological environment of biological cell and tissue. In PAQ/EG-H2O homogeneous solution, the excited triplet of PAQ （3PAQ＊） abstracts hydrogen atom from solvent EG. In PAQ/VC/EG-H2O solution, 3pAQ＊ abstracts hydrogen atom not only from solvent EG but also from VC. The quenching rate constant of 3pAQ＊ by VC is close to the diffusion-controlled value of 1.41 × 108 L/（mol.s）. In hexadecyltrimethylammonium bromide （CTAB）/EG-H2O and aerosol OT （AOT）/EG- H2O reversed micelle solutions, 3pAQ＊ and VC react around the water-oil interface of the reversed micelle. Exit of 3pAQ＊ from the lipid phase slows down the quenching reaction. For Triton X-100 （TX-100）/EG-H2O reversed micelle solution, PAQ and VC coexist inside the hydrophilic polyethylene glycol core, and the quenching rate constant of 3pAQ＊ by VC is larger than those in AOT/EG-H2O and CTAB/EG-H2O reversed micelle solutions, even a little larger than that in EG-H2O homogeneous solution. The strong emissive chemically induced dynamic electron polarization of As＇- resulted from the effective TM spin polarization transfer in hydrogen abstraction of 3pAQ＊ from VC.展开更多
基金supported in part by the Priority Academic Program Development of Jiangsu Higher Education Institutions and the State Key Laboratory of Crop Genetics and Germplasm Enhancement (Grant No. ZW201813)supported by the high-performance computing platform at the Bioinformatics Center of Nanjing Agricultural University。
文摘Ascorbic acid, also referred to as vitamin C(Vc), is an important nutrient found in fruits and vegetables that promotes produce quality and human health. Rosa roxburghii is an underutilized natural fruit that contains very high levels of Vc. However, the Vc content of R. roxburghii varies considerably during plant development and ripening. To better understand the molecular mechanisms that underlie fluctuations in Vc content of R. roxburghii fruit at different developmental stages, we performed transcriptomic and metabolomic analyses and identified two significant gene networks/modules and 168 transcription factors directly involved in Vc synthesis. Promoter analysis of two core genes involved in Vc synthesis, RrGGP and RrGalUR, revealed the presence of a retroviral long terminal repeat(LTR) insert in the RrGalUR promoter. Using yeast one-hybrid and dual-luciferase assays, we demonstrated that the transcription factors RrHY5H and RrZIP9 bind to the promoter of RrGGP to promote its expression. RrZIP6 and RrWRKY4 bind to the LTR in the RrGalUR promoter to promote its expression. Our results reveal a molecular mechanism that controls Vc synthesis and accumulation in R. roxburghii fruit.
基金Supported by The National Natural Science Foundation of China,No.82074061The National Key Research and Development Program of China,No.2022YFC2009600.
文摘BACKGROUND High-dose vitamin C treatment(HVCT)can reduce the adverse effect of chemotherapy and enhance the effect of antitumor therapy,which has been considered one of the safest alternative treatments.However,the severity of its adverse effects may have been underestimated.The most serious adverse effect is hemolysis,which may result in acute kidney injury or death.Although glucose-6-phosphate dehydrogenase(G6PD)deficiency is considered to be the main cause,the probability and pathological mechanism are not completely understood,leading to a lack of effective and standardized treatment methods.CASE SUMMARY Two patients with colorectal cancer developed hemolytic anemia after using 1 g/kg HVCT.In contrast to previous cases,the lowest hemoglobin level in the two cases was<50 g/L,which was lower than previously reported.This may be because Case 1 had chronic hepatitis B for many years,which caused abnormal liver reserve function,and Case 2 had grade II bone marrow suppression.Both patients improved and were discharged after blood replacement therapy.Our cases had the most severe degree of hemolysis but the best prognosis,suggesting that our treatment may be helpful for rescue of drug-induced hemolysis.This is the first review of the literature on hemolysis caused by HVCT,and we found that all patients with G6PD deficiency developed hemolysis after HVCT.CONCLUSION G6PD deficiency should be considered as a contraindication to HVCT,and it is not recommended for patients with bone marrow suppression,moderate-tosevere anemia,hematopoietic abnormalities,or abnormal liver and kidney function.Early blood purification and steroid therapy may avoid acute kidney injury or death caused by HVCT-related hemolytic anemia.
基金funded by the Nactional Natural Science Foundation of China(81872618)。
文摘Mental disorders seriously affect people’s health and social stability.This Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D(25(OH)D)levels and mental disorders.The data used for the MR analysis were derived from the summary genome-wide association studies(GWAS)database for VC and 25(OH)D and from the Finn Gen consortium for fourteen mental disorders.Based on the inverse variance weighted(IVW)method,we found a potential causal association between circulating VC and anxiety disorders(IVW:OR=1.139,95%CI:1.023-1.269,P=0.018).However,no causal association was found between VC or 25(OH)D and other mental disorders(P>0.05).In the reverse MR analysis,individuals with Alzheimer’s disease was causally associated with higher concentrations of circulating VC(P=0.012),while individuals with anxiety disorders had a negative association between the concentrations of 25(OH)D(P=0.012).However,the current evidence does not support a causal relationship between VC or 25(OH)D and other mental disorders.In addition,there was no causal association between circulating VC and 25(OH)D(P>0.05).Future studies are needed to confirm these findings and to elucidate the mechanisms of potential causality.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.20903004） and the Science Foundation of the Education Committee of Anhui Province （No.J2010A145）. We are grateful to professor Li-min Zhang for his help in transient absorptive spectrum measurement.
文摘Time-resolved electron spin resonance has been used to study quenching reactions between the antioxidant Vitamin C （VC） and the triplet excited states of 9,10-phenanthrenequinone （PAQ） in ethylene glycol-water （EG-H2O） homogeneous and inhomogeneous reversed micelle solutions. Reversed micelle solutions were used to be the models of physiological environment of biological cell and tissue. In PAQ/EG-H2O homogeneous solution, the excited triplet of PAQ （3PAQ＊） abstracts hydrogen atom from solvent EG. In PAQ/VC/EG-H2O solution, 3pAQ＊ abstracts hydrogen atom not only from solvent EG but also from VC. The quenching rate constant of 3pAQ＊ by VC is close to the diffusion-controlled value of 1.41 × 108 L/（mol.s）. In hexadecyltrimethylammonium bromide （CTAB）/EG-H2O and aerosol OT （AOT）/EG- H2O reversed micelle solutions, 3pAQ＊ and VC react around the water-oil interface of the reversed micelle. Exit of 3pAQ＊ from the lipid phase slows down the quenching reaction. For Triton X-100 （TX-100）/EG-H2O reversed micelle solution, PAQ and VC coexist inside the hydrophilic polyethylene glycol core, and the quenching rate constant of 3pAQ＊ by VC is larger than those in AOT/EG-H2O and CTAB/EG-H2O reversed micelle solutions, even a little larger than that in EG-H2O homogeneous solution. The strong emissive chemically induced dynamic electron polarization of As＇- resulted from the effective TM spin polarization transfer in hydrogen abstraction of 3pAQ＊ from VC.
