scholarly journals Vitamin C in Plants: From Functions to Biofortification

Antioxidants ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 519 ◽  
Author(s):  
Costantino Paciolla ◽  
Stefania Fortunato ◽  
Nunzio Dipierro ◽  
Annalisa Paradiso ◽  
Silvana De Leonardis ◽  
...  
Keyword(s):  
Vitamin C ◽  
Nutritional Value ◽  
Plant Stress ◽  
Free Radical Scavenger ◽  
Multiple Roles ◽  
Radical Scavenger ◽  
Human Metabolism ◽  
Physiological Processes ◽  
Gene Coding ◽  
Gulonolactone Oxidase

Vitamin C (l-ascorbic acid) is an excellent free radical scavenger, not only for its capability to donate reducing equivalents but also for the relative stability of the derived monodehydroascorbate radical. However, vitamin C is not only an antioxidant, since it is also a cofactor for numerous enzymes involved in plant and human metabolism. In humans, vitamin C takes part in various physiological processes, such as iron absorption, collagen synthesis, immune stimulation, and epigenetic regulation. Due to the functional loss of the gene coding for l-gulonolactone oxidase, humans cannot synthesize vitamin C; thus, they principally utilize plant-based foods for their needs. For this reason, increasing the vitamin C content of crops could have helpful effects on human health. To achieve this objective, exhaustive knowledge of the metabolism and functions of vitamin C in plants is needed. In this review, the multiple roles of vitamin C in plant physiology as well as the regulation of its content, through biosynthetic or recycling pathways, are analyzed. Finally, attention is paid to the strategies that have been used to increase the content of vitamin C in crops, emphasizing not only the improvement of nutritional value of the crops but also the acquisition of plant stress resistance.

scholarly journals Celastrol and Melatonin Modify SIRT1, SIRT6 and SIRT7 Gene Expression and Improve the Response of Human Granulosa-Lutein Cells to Oxidative Stress

Antioxidants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1871
Author(s):  
Rita Martín-Ramírez ◽  
Rebeca González-Fernández ◽  
Jairo Hernández ◽  
Pablo Martín-Vasallo ◽  
Angela Palumbo ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Free Radical ◽  
Cell Survival ◽  
Direct Effect ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Protective Agent ◽  
Physiological Processes

An excess of oxidative stress (OS) may affect several physiological processes fundamental to reproduction. SIRT1, SIRT6 and SIRT7 are involved in protection stress systems caused by OS, and they can be activated by antioxidants such as celastrol or melatonin. In this study, we evaluate SIRT1, SIRT6 and SIRT7 gene expression in cultured human granulosa-lutein (hGL) cells in response to OS inductors (glucose or peroxynitrite) and/or antioxidants. Our results show that celastrol and melatonin improve cell survival in the presence and absence of OS inductors. In addition, melatonin induced SIRT1, SIRT6 and SIRT7 gene expression while celastrol only induced SIRT7 gene expression. This response was not altered by the addition of OS inductors. Our previous data for cultured hGL cells showed a dual role of celastrol as a free radical scavenger and as a protective agent by regulating gene expression. This study shows a direct effect of celastrol on SIRT7 gene expression. Melatonin may protect from OS in a receptor-mediated manner rather than as a scavenger. In conclusion, our results show increased hGL cells survival with melatonin or celastrol treatment under OS conditions, probably through the regulation of nuclear sirtuins’ gene expression.

scholarly journals Melatonin as an Add-On Treatment of COVID-19 Infection: Current Status

Diseases ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 64
Author(s):  
Gregory M. Brown ◽  
Seithikurippu R. Pandi-Perumal ◽  
Harold Pupko ◽  
James L. Kennedy ◽  
Daniel P. Cardinali
Keyword(s):  
Free Radical Scavenger ◽  
Multiple Roles ◽  
Current Status ◽  
Controlled Study ◽  
Radical Scavenger ◽  
Randomized Controlled ◽  
Body Tissues ◽  
Tissue Responses ◽  
Cellular And Humoral Immunity ◽  
G Protein Coupled

This brief review was written to provide a perspective on the flurry of reports suggesting that melatonin can be an important add-on therapy for COVID-19. Despite the passage of more than 60 years since its discovery and much evidence representing the contrary, there has been great reluctance to conceive melatonin as anything other than a hormone. Many other body chemicals are known to have multiple roles. Melatonin was first shown to be a hormone derived from the pineal gland, to be actively synthesized there only at night, and to act on targets directly or via the G-protein-coupled receptors (GPCRs) superfamily. It is of note that over 40 years ago, it was also established that melatonin is present, synthesized locally, and acts within the gastrointestinal tract. A wider distribution was then found, including the retina and multiple body tissues. In addition, melatonin is now known to have non-hormonal actions, acting as a free radical scavenger, an antioxidant, and as modulating immunity, dampening down innate tissue responses to invaders while boosting the production of antibodies against them. These actions make it a potentially excellent weapon against infection by the SARS-CoV-2 virus. Early published results support that thesis. Recently, a randomized controlled study reported that low doses of melatonin significantly improved symptoms in hospitalized COVID-19 patients, leading to more rapid discharge with no side effects, while significantly decreasing levels of CRP, proinflammatory cytokines, and modulating dysregulated genes governing cellular and humoral immunity. It is now critical that these trials be repeated, with dose-response studies conducted and safety proven. Numerous randomized controlled trials are ongoing, which should complete those objectives while also allowing for a more thorough evaluation of the mechanisms of action and possible applications to other severe diseases.

Genetic variations within the vitamin C transporter genes to predict outcome in metastatic colorectal cancer patients treated with first-line FOLFIRI and bevacizumab: Data from FIRE-3 trial.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 11507-11507
Author(s):  
Martin D. Berger ◽  
Sebastian Stintzing ◽  
Dongyun Yang ◽  
Shu Cao ◽  
Yuji Miyamoto ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Vitamin C ◽  
Metastatic Colorectal Cancer ◽  
Direct Sequencing ◽  
Negative Control ◽  
Free Radical Scavenger ◽  
Phase Iii ◽  
Radical Scavenger ◽  
First Line ◽  
Transporter Proteins

11507 Background: Vitamin C is involved in many critical metabolic processes. Beside its major role as an antioxidant and free radical scavenger vitamin C exerts a regulatory influence on angiogenesis. Additionally, epidemiologic studies show an association between vitamin C levels and incidence of cancer.We therefore hypothesize that variations in genes encoding for vitamin C transporter proteins may predict outcome in patients (pts) with metastatic colorectal cancer (mCRC) treated with FOLFIRI and bevacizumab (bev). Methods: Theimpact of 3 functional SNPs within the SVCT1, SVCT2 and Glut1 genes on outcome was evaluated in 292 pts with mCRC treated with first-line FOLFIRI/bev in the randomized phase III FIRE-3 trial. 294 pts receiving FOLFIRI and cetuximab (cet) (FIRE-3) served as a negative control. Genomic DNA was extracted from formalin fixed paraffin embedded tissue and SNPs were analyzed by PCR-based direct sequencing. Results: Baseline characteristics in the FOLFIRI/bev arm were as follows: female/male 99/193; median age = 65y andmedian PFS/OS = 10.1/24.2 months (mts). The SVCT1 rs11242462 SNP showed significant association with PFS. T allele carriers had a longer median PFS compared to those with a C/C genotype (10.7 vs 9.7 mts) in both univariate (HR 0.77, p = 0.046) and multivariate analysis (HR 0.73, p = 0.028). The effect on outcome was most significant among KRAS mutant pts. Here, T allele carriers showed a markedly prolonged PFS and OS compared to pts with a C/C genotype (12.5 vs 7.0 mts, HR 0.50, p = 0.018 and 32.8 vs 14.7 mts, HR 0.45, p = 0.009). These associations remained significant in multivariate analyses (p = 0.009 and p = 0.021, respectively). However, the favorable impact on outcome was not observed among T allele carriers treated with FOLFIRI/cet. Conclusions: Our results provide the first evidence that the SVCT1 polymorphism rs11242462 might serve as a predictive marker in pts with mCRC treated with FOLFIRI/bev in the first-line setting. Targeting vitamin C transporter proteins might be a promising approach to further improve treatment options against mCRC and to overcome resistance to anti-angiogenic therapy.

scholarly journals Melatonin in Medicinal and Food Plants: Occurrence, Bioavailability, and Health Potential for Humans

Cells ◽  
2019 ◽  
Vol 8 (7) ◽  
pp. 681 ◽  
Author(s):  
Bahare Salehi ◽  
Farukh Sharopov ◽  
Patrick Fokou ◽  
Agnieszka Kobylinska ◽  
Lilian Jonge ◽  
...  
Keyword(s):  
Cellular Tissue ◽  
Free Radical Scavenger ◽  
Food Plants ◽  
Radical Scavenger ◽  
Human Diet ◽  
Physiological Processes ◽  
Other Substances ◽  
Living Organisms ◽  
Antioxidant Effects ◽  
Generative Organs

Melatonin is a widespread molecule among living organisms involved in multiple biological, hormonal, and physiological processes at cellular, tissue, and organic levels. It is well-known for its ability to cross the blood–brain barrier, and renowned antioxidant effects, acting as a free radical scavenger, up-regulating antioxidant enzymes, reducing mitochondrial electron leakage, and interfering with proinflammatory signaling pathways. Detected in various medicinal and food plants, its concentration is widely variable. Plant generative organs (e.g., flowers, fruits), and especially seeds, have been proposed as having the highest melatonin concentrations, markedly higher than those found in vertebrate tissues. In addition, seeds are also rich in other substances (lipids, sugars, and proteins), constituting the energetic reserve for a potentially growing seedling and beneficial for the human diet. Thus, given that dietary melatonin is absorbed in the gastrointestinal tract and transported into the bloodstream, the ingestion of medicinal and plant foods by mammals as a source of melatonin may be conceived as a key step in serum melatonin modulation and, consequently, health promotion.

scholarly journals Iron induced genotoxicity: attenuation by vitamin C and its optimization

2014 ◽  
Vol 7 (3) ◽  
pp. 154-158 ◽  
Author(s):  
Nuzhat Parveen ◽  
Shoeb Ahmad ◽  
G.G. Hammad A. Shadab
Keyword(s):  
Dna Damage ◽  
Free Radical ◽  
Vitamin C ◽  
Free Radical Scavenger ◽  
Iron Sulfate ◽  
Radical Scavenger ◽  
Optimum Level ◽  
Acute Administration ◽  
Oxygen Species ◽  
Indirect Action

ABSTRACT Vitamin C (VC) is a well-known antioxidant and strong free radical scavenger. Its antioxidant activity is useful for protection of cellular macromolecules, particularly DNA, from oxidative damage induced by different agents. This study was undertaken to evaluate the optimum level of VC in attenuating the chromosome aberrations (CAs) and DNA damage after iron sulfate (FeSO4) acute administration in Wistar rats. The results exhibited that the increase of CAs and DNA damage induced by FeSO4, 200 mg Fe/kg, could be reduced significantly by VC pretreatment at the dose of 500 mg/kg (p<0.001), but not in the 100 mg/kg group. The findings provide evidence that VC at the dose of 500 mg/kg exerted a possible protective effect against FeSO4 induced CAs and DNA damage. The possible mechanisms of VC may be attributed to its property as a free radical scavenger or to its indirect action in reducing the level of reactive oxygen species (ROS).

Melatonin reduces high levels of lipid peroxidation induced by potassium iodate in porcine thyroid

2019 ◽  
pp. 1-7 ◽  
Author(s):  
Paulina Iwan ◽  
Jan Stepniak ◽  
Malgorzata Karbownik-Lewinska
Keyword(s):  
Lipid Peroxidation ◽  
Oxidative Damage ◽  
Membrane Lipids ◽  
Chemical Properties ◽  
Iodine Concentration ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Protective Effects ◽  
Potassium Iodate ◽  
Hormone Synthesis

Abstract. Iodine is essential for thyroid hormone synthesis. Under normal iodine supply, calculated physiological iodine concentration in the thyroid is approx. 9 mM. Either potassium iodide (KI) or potassium iodate (KIO3) are used in iodine prophylaxis. KI is confirmed as absolutely safe. KIO3 possesses chemical properties suggesting its potential toxicity. Melatonin (N-acetyl-5-methoxytryptamine) is an effective antioxidant and free radical scavenger. Study aims: to evaluate potential protective effects of melatonin against oxidative damage to membrane lipids (lipid peroxidation, LPO) induced by KI or KIO3 in porcine thyroid. Homogenates of twenty four (24) thyroids were incubated in presence of either KI or KIO3 without/with melatonin (5 mM). As melatonin was not effective against KI-induced LPO, in the next step only KIO3 was used. Homogenates were incubated in presence of KIO3 (200; 100; 50; 25; 20; 15; 10; 7.5; 5.0; 2.5; 1.25 mM) without/with melatonin or 17ß-estradiol. Five experiments were performed with different concentrations of melatonin (5.0; 2.5; 1.25; 1.0; 0.625 mM) and one with 17ß-estradiol (1.0 mM). Malondialdehyde + 4-hydroxyalkenals (MDA + 4-HDA) concentration (LPO index) was measured spectrophotometrically. KIO3 increased LPO with the strongest damaging effect (MDA + 4-HDA level: ≈1.28 nmol/mg protein, p < 0.05) revealed at concentrations of around 15 mM, thus corresponding to physiological iodine concentrations in the thyroid. Melatonin reduced LPO (MDA + 4-HDA levels: from ≈0.97 to ≈0,76 and from ≈0,64 to ≈0,49 nmol/mg protein, p < 0.05) induced by KIO3 at concentrations of 10 mM or 7.5 mM. Conclusion: Melatonin can reduce very strong oxidative damage to membrane lipids caused by KIO3 used in doses resulting in physiological iodine concentrations in the thyroid.

OPTIMASI KONDISI EKSTRAKSI SENYAWA AKTIF ANTIOKSIDAN DARI BIJI ANGGUR

2019 ◽  
Vol 3 (2) ◽  
pp. 35
Author(s):  
Kartini Kartini ◽  
Azminah Azminah
Keyword(s):  
Free Radical ◽  
Optimum Condition ◽  
Active Compound ◽  
Grape Seed ◽  
Free Radical Scavenger ◽  
Water Bath ◽  
Radical Scavenger ◽  
Optimum Conditions ◽  
Ethanolic Solution ◽  
Reduced Pressure

In order to prepare standardized extract, optimization of extraction conditions of grape seed has been done. These conditions are type of menstrum (50, 70 and 96% of ethanolic solution), length of extraction (1, 2 and 4 hours) also method of evaporation (reduced pressure and opened air). Activity on free radical scavenger used as parameters to determine optimum conditions. Based on EC50 (concentration which scavenge 50% amount of free radical) can be concluded that optimum condition for extracting antioxidant active compound from grape seed are 70% ethanolic solution as menstrum, length of extraction 1 hour and evaporation on opened air use water bath.

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