Dietary Vitamin C in Human Health

Mechanistic insights into advanced glycation end products production in glucose-lysine model system involved with ascorbic acid

Ascorbic acid (AA), despite being an essential vitamin, is also a potential precursor to form advanced glycation end products (AGEs) in heat-processed foods. The dual action of AA (act as an inhibitor and a precursor concurrently) in AGEs formation in glucose (Glu)-lysine (Lys) model system has been found in our previous study. However, the mechanism underlying the dual role of AA has not been elucidated. This study clarified that AA, when acting as an inhibitor, primarily suppresses AGEs formation via its pH-regulating capacity rather than its reductive (free radical scavenging) potential. When AA serves as a substrate, its reactivity to form AGEs depends on pH condition. We further elucidated the primary pathways of AA-mediated AGEs formation. Methylglyoxal (MGO), generated via 2,3-diketoglucose (2,3-DKG), remains the principal intermediate for CEL formation from AA. Xylosone, a highly reactive carbonyl compound derived from AA, emerges as the major intermediate for CML formation.

Nutritional insights into pulmonary fibrosis: a comprehensive review on the impact of vitamins

Pulmonary fibrosis is a fatal interstitial disease characterized by diffuse alveolitis, abnormal fibroblast proliferation, and extracellular matrix (ECM) accumulation, resulting in structural lung destruction and impaired lung function. Numerous studies have demonstrated that vitamins appear to play a crucial role in regulating inflammatory responses, cell differentiation, redox homeostasis, and collagen synthesis. Beyond their conventional nutritional functions, specific vitamins have recently been found to modulate various biological processes involved in pulmonary fibrosis. This study aims to provide a comprehensive overview of the current understanding regarding the impact of vitamins on pulmonary fibrotic disease.

Association of low vitamin C concentrations and low consumption of fresh fruit and vegetables with cardiovascular disease in type 2 diabetes

PURPOSE

Vitamin C is a fundamental antioxidant with important metabolic actions in several biological processes. Patients with type 2 diabetes (T2D) are exposed to oxidative stress as a consequence of an increased production of reactive oxygen species (ROS). The aims of the present study were to estimate the prevalence of vitamin C deficiency in ambulatory patients with T2D, to study the relationship between vitamin C levels and cardiovascular diseases and to correlate the consumption of fresh fruit and vegetables with vitamin C levels and the presence of cardiovascular diseases.

METHODS

Vitamin C levels, determined by high-performance liquid chromatography (HPLC), and consumption of fresh fruit and vegetables, assessed by a food frequency questionnaire, were measured in 200 outpatients with T2D. All other laboratory variables were measured by standard methods. The association between vitamin C and cardiovascular diseases was assessed by multivariable logistic regression analysis.

RESULTS

Vitamin C deficiency was found in 12.2% of the subjects. Vitamin C levels and consumption of fresh fruit and vegetables were lower in subjects with cardiovascular diseases. Consumption of fresh fruit and vegetables was associated with higher levels of vitamin C. In the multivariable analysis, vitamin C was independently associated with cardiovascular diseases.

CONCLUSION

In conclusion, our study suggests that vitamin C may have an inverse relationship with cardiovascular diseases. Intake of vitamin C from fresh fruit and vegetables could play a protective role.

Association between vitamin C, D, and K intake and inflammatory bowel disease risk: findings from 2009 to 2010 NHANES

BACKGROUND

Micronutrient deficiency is commonly observed in patients with inflammatory bowel disease (IBD), yet the role of certain dietary trace elements in the risk of IBD development remains unclear.

OBJECTIVES

This study aimed to investigate the relationship between vitamin C, D, and K intake and IBD risk.

METHODS

This study included 3,591 participants from the 2009-2010 National Health and Nutrition Examination Survey (NHANES). Multivariable logistic regression were conducted to assess associations between vitamin C, D, and K intake and IBD risk while controlling for multiple confounders. Subgroup analyses were employed to test the robustness of the associations across participants with various characteristics. Additionally, restricted cubic spline (RCS) analysis was conducted to investigate potential nonlinear relationships.

RESULTS

In the fully adjusted model, each 1 mcg increase in vitamin D intake was linked to an approximately 51% decrease in IBD risk (adjusted OR = 0.49, 95% CI: 0.25-0.98, p = 0.045). The benefit appeared stronger in women, individuals without hypertension, and non-smokers. No statistically significant associations were found between vitamin C or vitamin K intake and IBD risk. However, among individuals without diabetes, each 1 mcg increase in vitamin K intake was associated with an approximate 67% reduction in IBD risk (adjusted OR = 0.33, 95% CI: 0.12-0.94, p = 0.039). RCS analysis suggested a linear relationship between dietary micronutrient intake and IBD risk (vitamin D: p for nonlinearity = 0.127, p for overall = 0.015; vitamin C: p for nonlinearity = 0.984, p for overall = 0.937; vitamin K: p for nonlinearity = 0.736, p for overall = 0.434).

CONCLUSION

Increased vitamin D intake may reduce the risk of IBD, with more pronounced benefits in certain subgroups, highlighting the potential of vitamin D supplementation as a novel therapeutic approach for IBD prevention and management. Future well-designed studies should further test the therapeutic effects of vitamin D supplementation and investigate the associations of other dietary trace elements with IBD risk to better inform prevention and treatment approaches.

One-pot synthesis smartphone-assisted test strip based on food-grade Fe-β-Cyclodextrin nanozymes for rapid colorimetric analysis of ascorbic acid in foods and supplements

Accurate on-site analysis of food quality is of great significance for ensuring public health. Among them, ascorbic acid (AA) is an essential micronutrient widely used as an additive in juices and drugs to improve food quality and human health. In this work, we developed food-grade Fe-β-Cyclodextrin(Fe-β-CD) nanozymes based on inexpensive and readily available β-cyclodextrin and iron ions for the detection of AA. Fe-β-CD confirmed excellent peroxidase-like activity and oxidized colorless 3,3',5,5'-tetramethylbenzidine (TMB) to oxide TMB. AA could inhibit the oxidation reaction and cause blue to fade. Based on the above principles, Fe-β-CD nanozymes exhibited a low detection limit (3.4 μM) for detecting AA, with a wide linear range (10-300 μM). This method had been successfully used for the detection of AA in fruits and vitamin C tablets, and the results were consistent with the specified values. More importantly, an integrated smartphone-assisted Fe-β-CD@test strip colorimetric application platform constructed by one-pot method, the test strip also had better stability, and could be combined with smartphones to achieve convenient AA detection without using any instruments, which showed enormous potential for rapid and low-cost colorimetric detection of AA.

Ximenia caffra Sond. the magic wild indigenous plant that offers immense contribution as food and medicine

The wild indigenous African tree, Ximenia caffra Sond also commonly known as 'sour plum' and found in Southern Africa is traditionally used as a source of food and medicine by rural communities. Its fruit has been found to have vitamins, minerals, macronutrients, other important compounds such as phenolics and flavonoids. Other parts of the plant such as the seeds, roots and the leaves are used to treat vast different ailments such as cough, cancer, sexual transmitted disease and so on. Its polyphenols compounds that contribute to its antioxidant, anti-inflammatory, anticancer and antimicrobial activities. The aim of this review is to explore X. caffra, the indigenous fruit that has health benefit of nutraceuticals and medicinal food, therapeutic capabilities in traditional medicine. The words' Ximenia cafrra' were used. The juice of X. caffra fruits comprises several potentially beneficial phytochemicals, minerals, and initial assessment indicate a remarkable antioxidant capacity of the fruit.

Vitamin C: A Comprehensive Review of Its Role in Health, Disease Prevention, and Therapeutic Potential

Since Albert Szent-Györgyi discovered it and it became used in treating scurvy, vitamin C has attracted interest in many studies due to its unique properties. It is an important cofactor in the synthesis of collagen and hormones, and it is involved in immunity, iron absorption, and processes requiring antioxidants. Thus, this review aims to emphasize the importance and usefulness of vitamin C in improving quality of life and preventing various diseases (e.g., chronic diseases, cardiovascular diseases, cancer) but also for its use in treatments against infections, neurodegenerative diseases, and cancer. Although the studies presented provide essential information about the properties of VIC and its beneficial effect on health, some studies contradict these theories. In this respect, further studies on larger samples and over a longer period are needed to demonstrate the therapeutic potential of this nutrient. However, VIC remains a necessary vitamin that should be consumed daily to maintain optimal health and prevent deficiencies that can lead to scurvy and its associated complications.

Vitamin C: From Self-Sufficiency to Dietary Dependence in the Framework of Its Biological Functions and Medical Implications

Vitamin C is an organic compound biosynthesized in plants and most vertebrates. Since its discovery, the benefits of vitamin C use in the cure and prevention of various pathologies have been frequently reported, including its anti-oxidant, anti-inflammatory, anticoagulant, and immune modulatory properties. Vitamin C plays an important role in collagen synthesis and subsequent scurvy prevention. It is also required in vivo as a cofactor for enzymes involved in carnitine and catecholamine norepinephrine biosynthesis, peptide amidation, and tyrosine catabolism. Moreover, as an enzymatic cofactor, vitamin C is involved in processes of gene transcription and epigenetic regulation. The absence of the synthesis of L-gulono-1,4-lactone oxidase, a key enzyme in the pathway of vitamin C synthesis, is an inborn metabolism error in some fishes and several bird and mammalian species, including humans and non-human primates; it is caused by various changes in the structure of the original GULO gene, making these affected species dependent on external sources of vitamin C. The evolutionary cause of GULO gene pseudogenization remains controversial, as either dietary supplementation or neutral selection is evoked. An evolutionary improvement in the control of redox homeostasis was also considered, as potentially toxic H2O2 is generated as a byproduct in the vitamin C biosynthesis pathway. The inactivation of the GULO gene and the subsequent reliance on dietary vitamin C may have broader implications for aging and age-related diseases, as one of the most important actions of vitamin C is as an anti-oxidant. Therefore, an important aim for medical professionals regarding human and animal health should be establishing vitamin C homeostasis in species that are unable to synthesize it themselves, preventing pathologies such as cardiovascular diseases, cognitive decline, and even cancer.

The relationship between serum vitamin C levels and high-sensitivity C-reactive protein in children

The relationship between vitamin C nutritional status and inflammation has garnered increasing attention, but studies in younger populations are limited. This study aimed to investigate the association between serum vitamin C and high-sensitivity C-reactive protein (hs-CRP) levels in children and adolescents. A cross-sectional analysis was conducted using data from the National Health and Nutrition Examination Survey (NHANES). The demographic data of 1766 participants aged 6-19 years were analyzed using t-tests and chi-square tests. The relationship between serum vitamin C and hs-CRP levels was analyzed using logistic regression, trend tests, and smooth curve fitting. Subgroup analyses and interaction tests were performed to assess the stability of the relationship across different populations. Our findings indicated a negative correlation between serum vitamin C and hs-CRP levels. In the fully adjusted model, each unit increase in serum vitamin C was associated with a reduction of 0.84 mg/L in hs-CRP levels (β = -0.84, 95% confidence interval [CI]: -1.34, -0.35). The hs-CRP levels in the vitamin C saturating group were 3.04 mg/L lower than those in the deficiency group (β = -3.04, 95% CI: -4.99, -1.08). This correlation was more significant in males, individuals with a family income to poverty ratio of ≤ 1.3, and those with a body mass index of ≥ 30 kg/m2. Serum vitamin C levels were negatively correlated with hs-CRP levels in American children and adolescents aged 6-19 years. Males, individuals from low-income families, and those who are overweight derived greater benefits from higher serum vitamin C concentrations.

Evaluating citrus juice: A comparative study of physicochemical, nutraceutical, antioxidant, and antimicrobial properties of citrus juices from Nepal

Citrus fruit juice is highly beneficial to human health, providing essential nutrients like carbohydrates, vitamins, phytochemicals, and antioxidants. Juices from citrus fruit varieties grown in various regions of Nepal were analyzed for their physicochemical properties, nutraceutical content, antioxidant and antimicrobial properties. The pH of the juices ranged between 2.09 and 3.62, while total soluble solids (TSS) varied from 7° Brix to 12.3 °Brix. Among varieties, C. aurantifolia exhibited the highest titratable acidity at 7.39 g/100 mL. C. limon showed the highest moisture content (94.74 %), C. reticulata had the highest carbohydrate content (14.6 ± 0.4 g/100 mL, n = 3), and C. aurantifolia presented the highest protein content (34.1 ± 0.7 mg/100 mL). C. sinensis recorded the highest flavonoid content (91.4 ± 0.3 mg/100 mL), C. reticulata had the highest phenolic content (65.8 ± 0.6 mg/100 mL), and C. limon exhibited the highest ascorbic acid content (45.1 ± 0.4 mg/100 mL). The methanolic extracts of all citrus fruit juices demonstrated robust antioxidant properties, as determined by DPPH assay. Notably, C. limon and C. aurantifolia juice extracts demonstrated significant antimicrobial activity against a wide range of microbes. This study highlights the variation in nutrient and phytochemicals compositions among different citrus fruit juices, underscoring the nutritional and medicinal benefits of citrus species.

Liposomal delivery enhances absorption of vitamin C into plasma and leukocytes: a double-blind, placebo-controlled, randomized trial

PURPOSE

L-Ascorbic acid (vitamin C) is an essential water-soluble vitamin that plays an important role in various physiological functions, including immune health. The stability of vitamin C in the gastrointestinal tract its bioavailability is limited. This study aimed to investigate if a liposomal form of vitamin C can increase absorption compared to standard vitamin C.

METHODS

In a randomized, double-blind, placebo-controlled, crossover fashion, 19 males and 8 females (n = 27; 36.0 ± 5.1 years, 165.0 ± 6.9 cm, 70.6 ± 7.1 kg) ingested a single-dose of placebo (PLA), 500 mg vitamin C (VIT C), and 500 mg liposomal vitamin C (LV-VIT C, LipoVantage®, Specnova, LLC, Tyson Corner, VA, USA). Venous blood samples were collected 0, 0.5-, 1-, 1.5-, 2-, 3-, 4-, 6-, 8-, 12-, and 24-hours after ingestion and were analyzed for plasma and leukocyte vitamin C concentration.

RESULTS

VIT C and LV-VIT C demonstrated significantly greater Cmax and AUC0 - 24 in plasma and in leukocytes compared to placebo (p < 0.001). Additionally, LV-VIT C had significantly higher Cmax (plasma + 27%, leukocytes + 20%, p < 0.001) and AUC0 - 24 (plasma + 21%, leukocytes + 8%, p < 0.001) values as compared to VIT C.

CONCLUSION

Liposomal formulation of vitamin C increases absorption into plasma and leukocytes.

TRIAL REGISTRATION

Clinical Trials Registry - India (CTRI/2023/04/051789).

Integrated omics analysis reveals the alteration of gut microbiota and fecal metabolites in Cervus elaphus kansuensis

The gut microbiota is the largest and most complex microecosystem in animals. It is influenced by the host's dietary habits and living environment, and its composition and diversity play irreplaceable roles in animal nutrient metabolism, immunity, and adaptation to the environment. Although the gut microbiota of red deer has been studied, the composition and function of the gut microbiota in Gansu red deer (Cervus elaphus kansuensis), an endemic subspecies of red deer in China, has not been reported. In this study, the composition and diversity of the gut microbiome and fecal metabolomics of C. elaphus kansuensis were identified and compared for the first time by using 16S rDNA sequencing, metagenomic sequencing, and LC-MS/MS. There were significant differences in gut microbiota structure and diversity between wild and farmed C. elaphus kansuensis. The 16S rDNA sequencing results showed that the genus UCRD-005 was dominant in both captive red deer (CRD) and wild red deer (WRD). Metagenomic sequencing showed similar results to those of 16S rDNA sequencing for gut microbiota in CRD and WRD at the phylum and genus levels. 16S rDNA and metagenomics sequencing data suggested that Bacteroides and Bacillus might serve as marker genera for CRD and WRD, respectively. Fecal metabolomics results showed that 520 metabolites with significant differences were detected between CRD and WRD and most differential metabolites were involved in lipid metabolism. The results suggested that large differences in gut microbiota composition and fecal metabolites between CRD and WRD, indicating that different dietary habits and living environments over time have led to the development of stable gut microbiome characteristics for CRD and WRD to meet their respective survival and reproduction needs. KEY POINTS: • Environment and food affected the gut microbiota and fecal metabolites in red deer • Genera Bacteroides and Bacillus may play important roles in CRD and WRD, respectively • Flavonoids and ascorbic acid in fecal metabolites may influence health of red deer.

Studies of genetic diversity and genome-wide association for vitamin C content in lettuce (Lactuca sativa L.) using high-throughput SNP arrays

Lettuce (Lactuca sativa L.) is a source of beneficial compounds though they are generally present in low quantities. We used 40K Axiom and 9K Infinium SNP (single nucleotide polymorphism) arrays to (i) explore the genetic variability in 21 varieties and (ii) carry out genome-wide association studies (GWAS) of vitamin C content in21 varieties and a population of 205 plants from the richest variety in vitamin C ('Lechuga del Pirineo'). Structure and phylogenetic analyses showed that the group formed mainly by traditional varieties was the most diverse, whereas the red commercial varieties clustered together and very distinguishably apart from the rest. GWAS consistently detected, in a region of chromosome 2, several SNPs related to dehydroascorbic acid (a form of vitamin C) content using three different methods to assess population structure, subpopulation membership coefficients, multidimensional scaling, and principal component analysis. The latter detected the highest number of SNPs (17) and the most significantly associated, 12 of them showing a high linkage disequilibrium with the lead SNP. Among the 84 genes in the region, some have been reported to be related to vitamin C content or antioxidant status in other crops either directly, like those encoding long non-coding RNA, several F-box proteins, and a pectinesterase/pectinesterase inhibitor, or indirectly, like extensin-1-like protein and endoglucanase 2 genes. The involvement of other genes identified within the region in vitamin C levels needs to be further studied. Understanding the genetic control of such an important quality trait in lettuce becomes very relevant from a breeding perspective.

Anti-Inflammatory Effects of Aptamin C in Pulmonary Fibrosis Induced by Bleomycin

Background/Objectives: Vitamin C is a well-known antioxidant with antiviral, anticancer, and anti-inflammatory properties. However, its therapeutic applications are limited by rapid oxidation due to heat and light sensitivity. Aptamin C, which employs aptamers to bind vitamin C, has demonstrated enhanced stability and efficacy. This study investigates the potential of Aptamin C to inhibit the progression of pulmonary fibrosis, a prominent inflammatory lung disease with no effective treatment. Methods: Mice bearing bleomycin-induced pulmonary fibrosis were administered vitamin C or Aptamin C, and their weight changes and survival rates were monitored. Inflammatory cell infiltration was assessed in the bronchoalveolar lavage fluid (BALF), and the degree of alveolar fibrosis was measured by H&E and Masson's trichrome staining. To elucidate the mechanism of action of Aptamin C, Western blot analysis was performed in HaCaT and lung tissues from bleomycin-induced pulmonary fibrosis mice. Results: The Aptamin C-treated group showed a notably higher survival rate at 50%, whereas all subjects in the vitamin C-treated group died. Histological examination of lung tissue showed that inflammation was significantly suppressed in the Aptamin C-supplemented group compared to the vitamin C-supplemented group, with a 10% greater reduction in cell infiltrations, along with noticeably less tissue damage. Additionally, it was observed that Aptamin C increased SVCT-1 expression in the HaCaT cells and the lung tissues. Conclusions: Taken together, Aptamin C not only increases the stability of vitamin C but also induces an increase in SVCT-1 expression, facilitating greater vitamin C absorption into cells and tissues, thereby inhibiting the progression of symptoms and associated inflammatory responses in pulmonary fibrosis.

The Role of Early Child Nutrition in Pulmonary Hypertension-A Narrative Review

Pulmonary hypertension is a complex condition that has distinct characteristics in pediatric populations. This review explores the important role of early childhood nutrition in the growth, progression, and management of pediatric pulmonary hypertension. Nutritional deficiencies, including those of vitamins C, D, and iron, are closely linked to worse outcomes in children with this disease, emphasizing the importance of early intervention to prevent malnutrition and promote growth. Emerging research revealed that promising nutrients like resveratrol, along with modulation of the gut and respiratory microbiomes, may offer therapeutic advances for managing pulmonary hypertension. However, the current literature is limited by a lack of pediatric-specific studies, with much of the data extrapolated from adult populations and animal models, especially rats. This review highlights the need for targeted research to develop effective nutritional interventions aimed at improving outcomes for pediatric patients.

From Orchard to Wellness: Unveiling the Health Effects of Sweet Cherry Nutrients

This review paper explores the multifaceted relationship between sweet cherry nutrients and human health, aiming to uncover the comprehensive impact of these bioactive compounds from orchard to wellness. Furthermore, it highlights how advanced crop techniques can be pivotal in optimizing these beneficial compounds. Synthesizing existing literature, the paper examines the diverse bioactive nutrients in sweet cherries, including antioxidants, polyphenols, vitamins, and minerals, and elucidating their mechanisms of action and potential health benefits. From antioxidant properties to anti-inflammatory effects, the paper elucidates how these nutrients may mitigate chronic diseases such as cardiovascular disorders, diabetes, and neurodegenerative conditions. Additionally, it explores their role in promoting gastrointestinal health, enhancing exercise recovery, and modulating sleep patterns. The review discusses emerging research on the potential anti-cancer properties of sweet cherry compounds, highlighting their promising role in cancer prevention and treatment. Furthermore, it delves into the impact of sweet cherry consumption on metabolic health, weight management, and skin health. By providing a comprehensive overview of the current understanding of sweet cherry nutrients and their health effects, this paper offers valuable insights for researchers, healthcare professionals, and consumers interested in utilizing nature's bounty for holistic wellness.

Overview of Phytochemical Composition of Brassica oleraceae var. capitata Cultivars

The Brassicaceae family includes a wide range of horticultural crops of economic and traditional importance, consumed either fresh, cooked, or fermented. Cabbage (Brassica oleraceae var. capitata) is one of the most important crops of the family. The present review analyzes the most important phytochemicals present in cabbage, focusing on variation of phytochemical composition between cultivars of B. oleraceae var. capitata f. alba, B. oleraceae var. capitata f. rubra, B. oleraceae var. capitata f. acuta, and B. oleraceae var. capitata f. sabauda. Cabbage form and cultivars significantly affect phytochemical compositions. B. oleraceae var. capitata f. rubra cultivars are generally great sources of phenolic compounds, especially anthocyanins, whereas B. oleraceae var. capitata f. alba cultivars display the highest concentration of glucosinolates; nevertheless, their levels are also dependent on the specific cultivar. B. oleraceae var. capitata f. acuta cultivars may be considered advantageous due to their high glucosinolate content and consistent phytochemical composition. Recognizing the benefits of specific cultivars can be valuable for consumers seeking a healthier lifestyle, as well as for scientists aiming to enhance cultivars through breeding programs or use plants' extracts to produce high quality pigments and dietary supplements.

Vitamin C in the Management of Thyroid Cancer: A Highway to New Treatment?

Thyroid cancer (TC) is the most common endocrine malignancy, with an increased global incidence in recent decades, despite a substantially unchanged survival. While TC has an excellent overall prognosis, some types of TC are associated with worse patient outcomes, depending on the genetic setting. Furthermore, oxidative stress is related to more aggressive features of TC. Vitamin C, an essential nutrient provided with food or as a dietary supplement, is a well-known antioxidant and a scavenger of reactive oxygen species; however, at high doses, it can induce pro-oxidant effects, acting through multiple biological mechanisms that play a crucial role in killing cancer cells. Although experimental data and, less consistently, clinical studies, suggest the possibility of antineoplastic effects of vitamin C at pharmacological doses, the antitumor efficacy of this nutrient in TC remains at least partly unexplored. Therefore, this review discusses the current state of knowledge on the role of vitamin C, alone or in combination with other conventional therapies, in the management of TC, the mechanisms underlying this association, and the perspectives that may emerge in TC treatment strategies, and, also, in light of the development of novel functional foods useful to this extent, by implementing novel sensory analysis strategies.

Association between dietary vitamin C intake and gout among American adults

Introduction

Gout is a common type of inflammatory arthritis. Vitamin C is a potent antioxidant that neutralizes reactive oxygen species. However, the association between dietary vitamin C levels and gout remains unclear. This study evaluated the relationship between dietary vitamin C intake and gout.

Methods

Cross-sectional data from individuals aged > 20 years who participated in the National Health and Nutrition Examination Survey between 2013 and 2018 were collected. Details on gout, dietary vitamin C intake, and several other essential variables were recorded.

Results

There were 12589 participants, 5% (652/12589) of whom experienced gout. Compared with individuals with lower vitamin C consumption in the Q1 group (≤19.9 mg/day), the adjusted odds ratio(OR)values for dietary vitamin C intake and gout in the Q2 group (19.9-49.7 mg/day), Q3 group (49.7-110.375 mg/day), and Q4 group (≥110.375 mg/day) were 0.87 (95% confidence interval (CI): 0.69-1.1, P = 0.237), 0.81 (95% CI: 0.64-1.02, P = 0.076), and 0.77 (95% CI: 0.6-0.99, P= 0.042), respectively. Accordingly, the association between dietary vitamin C intake and gout exhibited an L-shaped curve (nonlinear, P = 0.245) in a restricted cubic spline. Subgroup analysis revealed significant interactions between vitamin C levels and gout according to sex (P < 0.05). When we used data on dietary vitamin C from the second survey, we observed a similar inverse association between vitamin C intake and gout. The vitamin C was also negatively associated with hyperuricemia (OR, 0.94; 95% CI, 0.9-0.98, P=0.005). Compared with Q1, the adjusted OR values for dietary vitamin C and hyperuricemia in Q2, Q3, and Q4 were 0.77 (95% CI: 0.69-0.86, P = 0.65), 0.81 (95% CI: 0.72-0.91, P = 0.014), and 0.72 (95% CI: 0.64-0.81, P < 0.001), respectively. No association was observed between vitamin C supplementation and gout.

Conclusion

The population-based data indicate that dietary vitamin C intake is inversely associated with gout. These findings support the potential role of vitamin C in preventing gout.

Vitamin C deficiency after kidney transplantation: a cohort and cross-sectional study of the TransplantLines biobank

PURPOSE

Vitamin C deficiency is associated with excess mortality in kidney transplant recipients (KTR). We aim to evaluate plasma vitamin C status at different post-transplantation moments and assess the main characteristics associated with vitamin C deficiency in KTR.

METHODS

Plasma vitamin C was assessed in 598 KTR at 3-, 6-, 12-, 24-, and 60-months post-transplantation, 374 late KTR with a functioning graft ≥ 1 year, and 395 potential donors. Vitamin C deficiency was defined as plasma vitamin C ≤ 28 µmol/L. Diet was assessed by a 177-item food frequency questionnaire. Data on vitamin C-containing supplements use were extracted from patient records and verified with the patients.

RESULTS

Vitamin C deficiency ranged from 46% (6-months post-transplantation) to 30% (≥ 1 year post-transplantation). At all time points, KTR had lower plasma vitamin C than potential donors (30-41 µmol/L vs 58 µmol/L). In cross-sectional analyses of the 953 KTR at their first visit ≥ 12 months after transplantation (55 ± 14 years, 62% male, eGFR 55 ± 19 mL/min/1.73 m2), the characteristics with the strongest association with vitamin C deficiency were diabetes and smoking (OR 2.67 [95% CI 1.84-3.87] and OR 1.84 [95% CI 1.16-2.91], respectively). Dietary vitamin C intake and vitamin C supplementation were associated with lower odds (OR per 100 mg/day 0.38, 95% CI 0.24-0.61 and OR 0.21, 95% CI 0.09-0.44, respectively).

CONCLUSION

Vitamin C deficiency is frequent among KTR regardless of the time after transplantation, especially among those with diabetes and active smokers. The prevalence of vitamin C deficiency was lower among KTR with higher vitamin C intake, both dietary and supplemented. Further research is warranted to assess whether correcting this modifiable risk factor could improve survival in KTR.

Relationship between serum vitamin C and serum uric acid in people with different BMIs: results from the NHANES 2017-2018 and Mendelian randomization study

Objective

To examine the association of overweight/obesity and serum vitamin C (serum VC) with serum uric acid (SUA) and to assess causality using Mendelian randomization (MR).

Methods

4,772 participants from the National Health and Nutrition Examination Survey (NHANES), 2017-2018 were included in this study. Multivariate linear regression, variance inflation factor and quantile regression were used to analyze the relationships between overweight/obesity and serum VC and SUA levels. Secondly, Mendelian randomization (MR) was utilized to mitigate bias and prevent reverse causality in the observational study. Genetic variants associated with obesity (N = 13,848), vitamin C levels (N = 64,979) and serum uric acid levels (N = 343,836) were sourced from the most extensive genome-wide association studies (GWAS). The primary analytical method employed was inverse variance weighted (IVW).

Results

Based on the observational study, BMI was positively associated with SUA (β = 0.06, 95% CI: 0.05 to 0.07, p < 0.001) and serum VC was negatively associated with SUA (β = -0.14, 95% CI: -0.23 to -0.04, p = 0.005). In individuals with overweight/obesity (BMI > =25), the negative effects of serum VC on SUA enhanced with increasing serum VC. High serum VC level (Q4 level, above 1.19 mg/dL) reduced SUA (β = -0.30, 95% CI: -0.47 to -0.14, p < 0.001) in individuals with overweight/obesity compared to low serum VC level (Q1 level, below 0.54 mg/dL). IVW-MR analysis revealed a significant association between SUA levels and genetically elevated levels of VC (β = -0.03, 95% CI: -0.06 to -0.00, p = 0.029) and obesity (β = 0.06, 95% CI: 0.04 to 0.07, p < 0.001).

Conclusion

Cross-sectional observational analysis revealed that BMI exhibited a positive correlation with SUA levels and that serum VC was negatively correlated with SUA levels; moreover, moderate serum VC can reduce SUA, especially in individuals with overweight/obesity. There was evidence indicating a causal effect of VC and obesity on SUA. It highlights the importance of VC in the management of SUA levels, particularly in overweight/obese individuals. The findings might be helpful for the management of high SUA levels.

Exosomes isolated from citrus lemon: a promising candidate for the treatment of Alzheimer's disease

Aim: To investigate the efficacy of exosome-like nanovesicles from citrus lemon (EXO-CLs) in combating oxidative stress associated with Alzheimer's disease.Materials & methods: EXO-CLs were isolated through differential ultracentrifugation, characterized for particle size and evaluated for antioxidant activity.Results: EXO-CLs exhibited a mean size of 93.77 ± 12.31 nm, demonstrated permeability across the blood-brain barrier (BBB) and displayed antioxidant activity comparable to ascorbic acid. Additionally, they were found to be non-toxic, with over 80% cell viability observed in SH-SY5Y cells.Conclusion: The study proposes that EXO-CLs could serve as an effective treatment for neurodegenerative diseases. This suggests a promising approach for targeted interventions in brain-related disorders, owing to the antioxidant properties and BBB permeability exhibited by EXO-CLs.

Alternative pathways leading to ascorbate biosynthesis in plants: lessons from the last 25 years

l-Ascorbic acid (AsA) is an antioxidant with important roles in plant stress physiology, growth, and development. AsA also plays an essential role in human health, preventing scurvy. Humans do not synthesize AsA, which needs to be supplied via a diet rich in fresh produce. Research efforts have provided progress in the elucidation of a complex metabolic network with at least four routes leading to AsA formation in plants. In this review, three alternative pathways, namely the d-galacturonate, the l-gulose, and the myo-inositol pathways, are presented with the supporting evidence of their operation in multiple plant species. We critically discuss feeding studies using precursors and their conversion to AsA in plant organs, and research where the expression of key genes encoding enzymes involved in the alternative pathways showed >100% AsA content increase in the transgenics and in many cases accompanied by enhanced tolerance to multiple stresses. We propose that the alternative pathways are vital in AsA production in response to stressful conditions and to compensate in cases where the flux through the d-mannose/l-galactose pathway is reduced. The genes and enzymes that have been characterized so far in these alternative pathways represent important tools that are being used to develop more climate-tolerant crops.

An Isotonic Drink Containing Pacific Cod (Gadus macrocephalus) Processing Waste Collagen Hydrolysate for Bone and Cartilage Health

Malnutrition is one of the major factors of bone and cartilage disorders. Pacific cod (Gadus macrocephalus) processing waste is a cheap and highly promising source of bioactive substances, including collagen-derived peptides and amino acids, for bone and cartilage structure stabilization. The addition of these substances to a functional drink is one of the ways to achieve their fast intestinal absorption. Collagen hydrolysate was obtained via enzymatic hydrolysis, ultrafiltration, freeze-drying, and grinding to powder. The lyophilized hydrolysate was a light gray powder with high protein content (>90%), including collagen (about 85% of total protein) and a complete set of essential and non-essential amino acids. The hydrolysate had no observed adverse effect on human mesenchymal stem cell morphology, viability, or proliferation. The hydrolysate was applicable as a protein food supply or a structure-forming food component due to the presence of collagen fiber fragments. An isotonic fitness drink (osmolality 298.1 ± 2.1 mOsm/L) containing hydrolysate and vitamin C as a cofactor in collagen biosynthesis was prepared. The addition of the hydrolysate did not adversely affect its organoleptic parameters. The production of such functional foods and drinks is one of the beneficial ways of fish processing waste utilization.

Dietary intake of polish organic and conventional fruit growers and their life partners - a pilot study

Diet is one of the elements that contribute to health and quality of life. There are significant discrepancies between the diets of people living in different regions, with different beliefs, or with different approaches to sustainability and ecology. There is a lack of research on dietary intake among organic and conventional fruit growers. The aim of our study was to examine the diets of orchardists and their immediate life partners in terms of meeting energy requirements, nutrient intake and fulfillment of dietary recommendations in this group. Fifty-three participants (28 in the organic group and 25 in the conventional group) took part in the study. Dietary data were obtained using the 3-day dietary record. Body mass and height were measured and BMI was calculated. Physical activity was estimated using a questionnaire method. The study group was aged 44 ± 8 years, with a body weight of 84 ± 16 kg and a height of 172 ± 9 cm. The mean BMI was 28 ± 4 kg/m2. Mean energy intake with diet was 2170 ± 606 kcal/day with needs of 3002 (1991-5144) kcal/day. A significant proportion of the study group did not fulfill their calcium and vitamin D requirements. In addition, a significant proportion of the conventional fruit growers did not cover their needs for potassium, magnesium and vitamins: E, C, and folate. Both groups had too high an intake of cholesterol and saturated fatty acids, and too low an intake of polyunsaturated fatty acids. In conclusion, the orchardists' diets mostly provided adequate amounts of nutrients, with inadequate intakes of calcium, vitamin D, cholesterol, and fatty acids. The diets of organic fruit growers were significantly richer in selected nutrients.

Uncommon Scurvy Manifestation: Solitary Skin Lesion in an Alcoholic Case

Scurvy, characterized by vitamin C deficiency, typically manifests with various symptoms, most commonly skin lesions. However, the presentation of a solitary skin lesion is considered atypical. An elderly patient with a history of heavy alcohol consumption presented with a small skin lesion that developed rapidly into a solitary open wound without any preceding trauma. Laboratory analysis revealed severe vitamin C deficiency (<5 μmol/L). The patient showed significant improvement following high-dose vitamin C replacement therapy. This case underscores the potential for scurvy to present with a solitary lower body wound devoid of typical symptoms. It highlights the importance of prompt consideration of vitamin C replacement therapy, particularly in high-risk groups such as alcoholics, by healthcare providers.

Vitamin C Inhibited Pulmonary Metastasis through Activating Nrf2/HO-1 Pathway

As an important nutritional component, vitamin C (Vc) shows good antitumor activity in a variety of cancer, but there are few studies in pulmonary metastasis. In order to verify its anticancer and antimetastatic effect, the study sets up H22 pulmonary metastasis mouse model. The results show that intraperitoneal injection of Vc inhibits pulmonary metastasis through up-regulating the expression of Nrf2, HO-1, cleaved caspases 3 and 9, and causing DNA damage and apoptosis which is similar to the pro-oxidant effect of Vc in p53 null cells (H1299 cells). Meanwhile, oral administration of Vc up-regulates the expression of p53, directly activates Nrf2/HO-1 pathway, increases expression of cleaved caspases 3 and 9, and ultimately inhibits pulmonary metastasis, which is the same as the antioxidant result of Vc in p53 wild-type cells. In addition, Vc inhibits the proliferation and migration of lung cancer cells in a concentration-dependent manner and has little cytotoxic effects on normal cells. Notably, the experiment further illustrates that besides intravenous Vc, oral Vc significantly inhibits the pulmonary metastasis in mice. All in all, these findings provide new clues for Vc-treated pulmonary metastasis in clinical research.

Serum vitamin C status of people in New South Wales: retrospective analysis of findings at a public referral hospital

OBJECTIVES

To examine the relationship between vitamin C status and demographic factors in New South Wales on the basis of serum vitamin C test results undertaken at the central pathology laboratory in Sydney, and to assess associations with age, gender, social disadvantage, and geographic remoteness.

DESIGN, SETTING

Retrospective observational study; analysis of vitamin C test results undertaken at the Royal Prince Alfred Hospital, 1 January 2017 - 31 December 2021.

MAIN OUTCOME MEASURES

Vitamin C status (normal, serum concentration ≥ 40 μmol/L; hypovitaminosis C, 12-39 μmol/L; significant deficiency, < 12 μmol/L); associations of vitamin C status with year of testing, age, gender, socio-economic status (Index of Relative Socio-Economic Advantage and Disadvantage quintile), and geographic remoteness (Australian Statistical Geography Standard); rate of hypovitaminosis C or significant deficiency test results (relative to findings of normal levels; per 100 000 estimated resident population) by Statistical Area 3.

RESULTS

Of 17 507 vitamin C tests undertaken during 2017-2021, 4573 were excluded (multiple tests for individuals); of 12 934 included results, 6654 were for women (51.5%), 9402 for people living in major cities (73.5%), and 81 for people in remote or very remote areas (0.6%). In multivariable multinomial regression analyses, significant deficiency (relative to normal test results) was more likely for men than women (adjusted odds ratio [aOR], 1.39; 95% confidence interval [CI], 1.27-1.52); the likelihood of hypovitaminosis C (IRSAD quintile 1 v 5, aOR, 1.35; 95% CI, 1.19-1.53) or significant deficiency (aOR, 2.07; 95% CI, 1.79-2.40) generally increased with postcode-level socio-economic disadvantage. Several of the population areas with the highest low vitamin C rates were areas of greatest disadvantage in NSW.

CONCLUSIONS

The prevalence of vitamin C deficiency among older people and people living in areas of socio-economic disadvantage indicates that population assessment of vitamin C levels would be appropriate.

Vitamin C intake and colorectal cancer survival according to KRAS and BRAF mutation: a prospective study in two US cohorts

BACKGROUND

The associations of vitamin C intake with colorectal cancer (CRC) survival according to tumour KRAS or BRAF mutation status remain unclear.

METHODS

We used the inverse probability weighted multivariable Cox proportional hazards regression model to calculate the hazard ratio (HR) of mortality, and spline analysis to evaluate the dose-response relationship in the Nurses' Health Study and Health Professionals Follow-up Study. We also assessed SLC2A1 mRNA expression according to KRAS or BRAF mutation in the TCGA database.

RESULTS

During an average of 12.0 years of follow-up, we documented 2,096 CRC cases, of which 703 cases had KRAS and BRAF mutation data. The association between total vitamin C intake and CRC-specific mortality suggestively differed according to KRAS or BRAF mutation status (Pinteraction = 0.04), with the multivariable HR (95% CI) per 400 mg/day increase in vitamin C intake for CRC-specific mortality of 1.07 (0.87-1.32, Ptrend = 0.52) in cases with both wild type and 0.74 (0.55-1.00, Ptrend < 0.05) in cases with either KRAS or BRAF mutant type. TCGA analysis showed a higher mRNA SLC2A1 expression in KRAS or BRAF-mutated tumours than in wild-type tumours (P = 0.02).

CONCLUSION

Our findings support the laboratory evidence for a potential benefit of vitamin C for CRC patients with KRAS or BRAF mutated tumours.

Scurvy: old disease, new lessons

Scurvy, the condition associated with severe vitamin C deficiency, is believed to be one of the oldest diseases in human history. It was particularly prevalent during the Age of Sail, when long sea voyages without access to fresh food resulted in an epidemic which claimed millions of lives; however, scurvy has existed across time and geography, occurring whenever and wherever diets are devoid of vitamin C. Young children, specifically, were affected by the emergence of 'infantile scurvy' in the 19th century owing to the use of heated milk and manufactured infant foods of poor nutritional quality. Scurvy continues to occur in at-risk groups. In children and youths, it is primarily observed in the context of autism spectrum disorder and feeding problems such as a limited food repertoire and high-frequency single food intake. Diagnosis may be delayed and invasive testing undertaken owing to clinicians' lack of familiarity with the disease, or the mistaken assumption that it is exclusively a disease of the past. The aetiology, clinical manifestations and treatment of scurvy are described. Its long history and current epidemiology are also reviewed, demonstrating that scurvy is very much a disease of the present. It is suggested that future efforts should focus on (i) anticipatory guidance and early nutritional intervention, informed by an understanding of scurvy's epidemiology, with the aim of preventing the disease in those at risk, and (ii) prompt recognition and treatment to minimise morbidity and healthcare costs.Abbreviations: ASD: autism spectrum disorder.

Vitamin C fortification: need and recent trends in encapsulation technologies

The multifaceted role of vitamin C in human health intrudes several biochemical functions that are but not limited to antioxidant activity, homoeostasis, amino acid synthesis, collagen synthesis, osteogenesis, neurotransmitter production and several yet to be explored functions. In absence of an innate biosynthetic pathway, humans are obligated to attain vitamin C from dietary sources to maintain its optimal serum level (28 μmol/L). However, a significant amount of naturally occurring vitamin C may deteriorate due to food processing, storage and distribution before reaching to the human gastrointestinal tract, thus limiting or mitigating its disease combating activity. Literature acknowledges the growing prevalence of vitamin C deficiency across the globe irrespective of geographic, economic and population variations. Several tools have been tested to address vitamin C deficiency, which are primarily diet diversification, biofortification, supplementation and food fortification. These strategies inherit their own advantages and limitations. Opportunely, nanotechnology promises an array of delivery systems providing encapsulation, protection and delivery of susceptible compounds against environmental factors. Lack of clear understanding of the suitability of the delivery system for vitamin C encapsulation and fortification; growing prevalence of its deficiency, it is a need of the hour to develop and design vitamin C fortified food ensuring homogeneous distribution, improved stability and enhanced bioavailability. This article is intended to review the importance of vitamin C in human health, its recommended daily allowance, its dietary sources, factors donating to its stability and degradation. The emphasis also given to review the strategies adopted to address vitamin c deficiency, delivery systems adopted for vitamin C encapsulation and fortification.

Unwinding the potentials of vitamin C in COVID-19 and other diseases: An updated review

Background: The discovery of vitamin C (ascorbic acid) is related to the ancient history of persistent research on the origins of the haemorrhagic disease scurvy. Vitamin C is an important nutrient that aids in a variety of biological and physiological processes. Scientists have been researching the function of vitamin C in the prevention and ailment of sepsis and pneumonia for decades. This has created a potential platform for applying these results to individuals suffering from severe coronavirus infection (COVID-19). Vitamin C's ability to activate and enhance the immune system makes it a promising treatment in the present COVID-19 pandemic. Vitamin C also aids in the activation of vitamin B, the production of certain neurotransmitters, and the transformation of cholesterol into bile acids. Hence, vitamin C is used for the treatment of many diseases. Aim: This review highlights the Vitamin C investigations that are performed by various researchers on patients with COVID 19 infection, the clinical studies and their observations. The authors have additionally updated information on the significance of vitamin C insufficiency, as well as its relevance and involvement in diseases such as cancer, wound healing, iron deficiency anaemia, atherosclerosis and neurodegenerative disorders. Here, we discuss them with the references. Methods: The method used in order to perform literature search was done using SciFinder, PubMed and ScienceDirect. Results: There is a potential role of vitamin C in various diseases including neurodegenerative disorders, COVID-19 and other diseases and the results are highlighted in the review with the help of clinical and preclinical data. Conclusion: More research on vitamin C and the undergoing clinical trials might prove a potential role of vitamin C in protecting the population from current COVID-19 pandemic.

Effect of Antioxidant Supplementation on NET Formation Induced by LPS In Vitro; the Roles of Vitamins E and C, Glutathione, and N-acetyl Cysteine

Neutrophil extracellular traps (NETs) require reactive oxygen species (ROS) to eliminate pathogens by inducing oxidative stress. However, this process can also cause tissue damage to the host. Neutrophils contain high concentrations of vitamin C (1.5 mM) compared to the bloodstream (0.1 mM), and this antioxidant can interact with vitamin E and glutathione (GSH) inside the cell to maintain the redox balance. Previous studies have investigated the effect of vitamins E or C and N-acetyl cysteine (NAC) on NET formation, but the interactions of these molecules in neutrophils remain unknown. In this study, we investigated the effect of antioxidants alone and two combinations on NET formation and oxidative stress. Neutrophils were pre-loaded with GSH + NAC or vitamin E + vitamin C + GSH + NAC (termed ALL), and LPS-induced NET formation was assessed using fluorometry and immunofluorescence. Antioxidant effects were evaluated by measuring the total antioxidant capacity (TAC), GSH/GSSG ratio, ROS production, nitrite + nitrate levels, and lipid peroxidation. Our results showed that even low doses of antioxidants are capable of decreasing NETs. Furthermore, the combinations augmented TAC and GSH/GSSG ratio and decreased ROS, nitrites + nitrates, and malondialdehyde (MDA) levels in supplemented neutrophils in vitro.

Investigation of Chemical Constituents and Antioxidant Activity of Biologically Active Plant-Derived Natural Products

The aim of this publication is to present rapid screening methods (visual/colorimetric) that will enable quick identification of the presence of biologically active compounds in aqueous solutions. For this reason, 26 plant extracts obtained by ultrasound-assisted extraction were analysed for the content of these compounds. Higher plants, used as a raw material for extraction, are common in Europe and are easily available. The article proposes a comparison of various protocols for the identification of various compounds, e.g., phenolic compounds (phenols, tannins, anthocyanins, coumarins, flavones, flavonoids), vitamin C, quinones, quinines, resins, glycosides, sugars. Initial characterisation of the composition of plant extracts using fast and inexpensive methods allows you to avoid the use of time-consuming analyses with the use of advanced research equipment. In addition, the antioxidant activity of plant extracts using spectrophotometric methods (DPPH, ABTS, FRAP assay) and quantitative analysis of plant hormones such as abscisic acid, benzoic acid, gibberellic acid, indole acetic acid, jasmonic acid, salicylic acid, zeatin, zeatin riboside, and isipentenyl adenine was performed. The obtained results prove that the applied visual methods show different sensitivity in detecting the sought chemical compounds. Therefore, it is necessary to confirm the presence or absence of bioactive substances and their concentration using modern analytical methods.

Regulation of gut microbiota by vitamin C, vitamin E and β-carotene

Vitamin C (VC), vitamin E (VE) and β-carotene (βC) are representative dietary antioxidants, which exist in daily diet and can increase the antioxidant capacity of body fluids, cells and tissues. The health benefits of vitamins like VC, VE and βC are widely demonstrated. Given that the strong associations between the gut microbiota and host health or a range of diseases has been extensively reported, it is important to explore the modulatory effects of known vitamins on the gut microbiota. Herein, this article reviews the effects of VC, VE and βC on the gut microbiota. Totally, 19 studies were included, of which eight were related to VC, nine to VE, and six to βC. Overall, VC, VE and βC can provide health benefits to the host by modulating the composition and metabolic activity of the gut microbiota, improving intestinal barrier function and maintaining the normal function of the immune system. Two perspectives are proposed for future studies: i) roles of known antioxidant activity of vitamins in regulating the gut microbiota and its molecular mechanism need to be further studied; ii) causal relationships between the regulatory effects of vitamins on gut microbiota and host health still remains to be further verified.

Atrazine Toxicity: The Possible Role of Natural Products for Effective Treatment

There are various herbicides which were used in the agriculture industry. Atrazine (ATZ) is a chlorinated triazine herbicide that consists of a ring structure, known as the triazine ring, along with a chlorine atom and five nitrogen atoms. ATZ is a water-soluble herbicide, which makes it capable of easily infiltrating into majority of the aquatic ecosystems. There are reports of toxic effects of ATZ on different systems of the body but, unfortunately, majority of these scientific reports were documented in animals. The herbicide was reported to enter the body through various routes. The toxicity of the herbicide can cause deleterious effects on the respiratory, reproductive, endocrine, central nervous system, gastrointestinal, and urinary systems of the human body. Alarmingly, few studies in industrial workers showed ATZ exposure leading to cancer. We embarked on the present review to discuss the mechanism of action of ATZ toxicity for which there is no specific antidote or drug. Evidence-based published literature on the effective use of natural products such as lycopene, curcumin, Panax ginseng, Spirulina platensis, Fucoidans, vitamin C, soyabeans, quercetin, L-carnitine, Telfairia occidentalis, vitamin E, Garcinia kola, melatonin, selenium, Isatis indigotica, polyphenols, Acacia nilotica, and Zingiber officinale were discussed in detail. In the absence of any particular allopathic drug, the present review may open the doors for future drug design involving the natural products and their active compounds.

Cellular Red-Ox system in health and disease: The latest update

Cells are continually exposed to reactive oxygen species (ROS) generated during cellular metabolism. Apoptosis, necrosis, and autophagy are biological processes involving a feedback cycle that causes ROS molecules to induce oxidative stress. To adapt to ROS exposure, living cells develop various defense mechanisms to neutralize and use ROS as a signaling molecule. The cellular redox networks combine signaling pathways that regulate cell metabolism, energy, cell survival, and cell death. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) are essential antioxidant enzymes that are required for scavenging ROS in various cell compartments and response to stressful situations. Among the non-enzymatic defenses, vitamin C, glutathione (GSH), polyphenols, carotenoids, vitamin E, etc., are also essential. This review article describes how ROS are produced as byproducts of oxidation/reduction (redox) processes and how the antioxidants defense system is directly or indirectly engaged in scavenging ROS. In addition, we used computational methods to determine the comparative profile of binding energies of several antioxidants with antioxidant enzymes. The computational analysis demonstrates that antioxidants with a high affinity for antioxidant enzymes regulate their structures.

Association of serum water-soluble vitamin exposures with the risk of metabolic syndrome: results from NHANES 2003-2006

Introduction

Existing evidence suggests an association between certain vitamins and metabolic syndrome (MetS), but few epidemiological studies have focused on the effects of multivitamin co-exposure on MetS. This study aims to investigate the associations of the individual or multiple water-soluble vitamins (i.e., vitamin C (VC), vitamin B9 (VB9), and vitamin B12 (VB12)) with co-exposure to MetS, as well as the dose-response relationships among them.

Methods

A cross-sectional study was conducted by employing the National Health and Examination Surveys (NHANESs) 2003-2006. Multivariate-adjusted logistic regression models were used to explore the association between individual serum water-soluble vitamins and the risk of MetS and its components, including waist circumference, triglyceride, high-density lipoprotein, blood pressure, and fasting plasma glucose. Restricted cubic splines were performed to explore the dose-response relationships among them. The quantile g-computation method was adopted to explore the associations of multiple water-soluble vitamins co-exposure with MetS risk and MetS components.

Results

A total of 8983 subjects were involved in the study, of whom 1443 were diagnosed with MetS. The MetS groups had a higher proportion of participants with age ≥60 years, BMI ≥30 kg/m², and insufficient physical activity. Compared with the lowest quartile, the third (OR=0.67, 95% CI: 0.48, 0.94) and highest quartiles (OR=0.52, 95%CI: 0.35, 0.76) of VC were associated with lower MetS risk. Restricted cubic splines showed negative dose-response relationships among VC, VB9 and VB12, and MetS. Regarding MetS components, higher VC quartiles were associated with lower waist circumference, triglyceride, blood pressure, and fasting plasma glucose, while higher VC and VB9 quartiles were associated with higher high-density lipoprotein (HDL). Co-exposure to VC, VB9, and VB12 was significantly inversely associated with MetS, with ORs (95% CI) of 0.81 (0.74, 0.89) and 0.84 (0.78, 0.90) in the conditional and marginal structural models, respectively. Furthermore, we found that VC, VB9, and VB12 co-exposure were negatively associated with waist circumference and blood pressure, while VC, VB9, and VB12 co-exposure were positively associated with HDL.

Conclusion

This study revealed negative associations of VC, VB9, and VB12 with MetS, while the high water-soluble vitamin co-exposure was associated with a lower MetS risk.

Association of Oral or Intravenous Vitamin C Supplementation with Mortality: A Systematic Review and Meta-Analysis

Mortality is the most clinically serious outcome, and its prevention remains a constant struggle. This study was to assess whether intravenous or oral vitamin C (Vit-C) therapy is related to reduced mortality in adults. Data from Medline, Embase, and the Cochrane Central Register databases were acquired from their inception to 26 October 2022. All randomized controlled trials (RCTs) involving intravenous or oral Vit-C against a placebo or no therapy for mortality were selected. The primary outcome was all-cause mortality. Secondary outcomes were sepsis, COVID-19, cardiac surgery, noncardiac surgery, cancer, and other mortalities. Forty-four trials with 26540 participants were selected. Although a substantial statistical difference was observed in all-cause mortality between the control and the Vit-C-supplemented groups (p = 0.009, RR 0.87, 95% CI 0.78 to 0.97, I2 = 36%), the result was not validated by sequential trial analysis. In the subgroup analysis, mortality was markedly reduced in Vit-C trials with the sepsis patients (p = 0.005, RR 0.74, 95% CI 0.59 to 0.91, I2 = 47%), and this result was confirmed by trial sequential analysis. In addition, a substantial statistical difference was revealed in COVID-19 patient mortality between the Vit-C monotherapy and the control groups (p = 0.03, RR 0.84, 95% CI 0.72 to 0.98, I2 = 0%). However, the trial sequential analysis suggested the need for more trials to confirm its efficacy. Overall, Vit-C monotherapy does decrease the risk of death by sepsis by 26%. To confirm Vit-C is associated with reduced COVID-19 mortality, additional clinical random control trials are required.

Mechanisms of Mitochondrial Oxidative Stress in Brain Injury: From Pathophysiology to Therapeutics

Mitochondrial oxidative stress has been implicated in various forms of brain injury, both traumatic and non-traumatic. Due to its oxidative demand, the brain is intimately dependent on its mitochondrial functioning. However, there remains appreciable heterogeneity in the development of these injuries regarding ROS and their effect on the sequelae. These include traumatic insults such as TBIs and intracranial hemorrhaging secondary to this. In a different vein, such injuries may be attributed to other etiologies such as infection, neoplasm, or spontaneous hemorrhage (strokes, aneurysms). Clinically, the manner of treatment may also be adjusted in relation to each injury and its unique progression in the context of ROS. In the current review, then, the authors highlight the role of mitochondrial ROS in various forms of brain injury, emphasizing both the collective and unique elements of each form. Lastly, these narratives are met with the current therapeutic landscape and the role of emerging therapies in treating reactive oxygen species in brain injuries.

Impact of intravenous vitamin C as a monotherapy on mortality risk in critically ill patients: A meta-analysis of randomized controlled trials with trial sequential analysis

BACKGROUND

This meta-analysis aimed at investigating the pooled evidence regarding the effects of intravenous vitamin C (IVVC) on mortality rate in critically ill patients.

METHODS

Databases including Medline, Embase, and Cochrane Library were searched from inception to October, 2022 to identify RCTs. The primary outcome was the risk of overall mortality. Subgroup analyses were performed based on IVVC dosage (i.e., cut-off value: 100 mg/kg/day or 10000 mg/day). Trial sequential analysis (TSA) was used to examine the robustness of evidence.

RESULTS

A total of 12 trials including 1,712 patients were analyzed. Although meta-analysis demonstrated a lower risk of mortality in patients with IVVC treatment compared to those without [risk ratio (RR): 0.76, 95% CI: 0.6 to 0.97, p = 0.02, I 2 = 36%, 1,711 patients), TSA suggested the need for more studies for verification. Moreover, subgroup analyses revealed a reduced mortality risk associated with a low IVVC dosage (RR = 0.72, p = 0.03, 546 patients), while no beneficial effect was noted with high IVVC dosage (RR = 0.74, p = 0.13, I 2 = 60%, 1,165 patients). The durations of vasopressor [mean difference (MD): -37.75 h, 404 patients) and mechanical ventilation (MD: -47.29 h, 388 patients) use were shorter in the IVVC group than those in the controls, while there was no significant difference in other prognostic outcomes (e.g., length of stay in intensive care unit/hospital) between the two groups.

CONCLUSION

Although intravenous vitamin C as a monotherapy reduced pooled mortality, durations of vasopressor use and mechanical ventilation, further research is required to support our findings and to identify the optimal dosage of vitamin C in the critical care setting.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42022371090.

East-Greenland traditional nutrition: a reanalysis of the Høygaard et al. nutritional data (1936-1937)

Greenlandic traditional nutrition was unique in the arctic environment. The aim of the present study was to reanalyse the Høygaard et al. data, focusing on two micronutrients object of discussion, i.e. Ca and vitamin C. Høygaard et al. left Copenhagen in August 1936 and stayed in East-Greenland until August 1937. The members of the expedition recorded nutritional intake whilst residing in families. However, the nutritional intake was analysed on a household level. In total, thirty-five adults and fourty-one children participated. Median total energy expenditure in kcal per d was estimated at 2978 and 2627 for male and female adults, respectively, and 1997 for children and adolescents. Median (IQR) energy consumption in kcal per d was 3881 (1568) for male and 2910 (882) for female adults. This was 2442 (857) and 2023 (1122) for male and female children and adolescents. Median (IQR) Ca intake in mg.d^-1 was 555 (1110) for male and 484 (883) for female adults. This was 458 (747) and 358 (838) for male and female children and adolescents. Median (IQR) vitamin C intake in mg.d^-1 was 79 (77) for male and 59 (56) for female adults. This was 44 (47) and 60 (52) for male and female children and adolescents. In this study, the importance of traditional foods in reaching an acceptable energy balance was emphasised, together with the confirmation of a low Ca intake in East-Greenland traditional dietary pattern, and the important role of algae consumption in Inuit traditional dietary pattern to avoid scurvy.

Recent Advances on Main Active Ingredients, Pharmacological Activities of Rosa roxbughii and Its Development and Utilization

Rosa roxburghii tratt (R. roxburghii) is an important plant resource that is widely distributed in the southwest of China and favored by consumers due to its high nutritional value and healthy functions. Meanwhile, it is a traditional edible and medicinal plant in China. With the deepening research of R. roxburghii, more and more bioactive components and its health care and medicinal value have been discovered and developed in recent years. This review summarizes and discusses the recent advances on main active ingredients such as vitamin, protein, amino acid, superoxide dismutase, polysaccharide, polyphenol, flavonoid, triterpenoid and mineral, and pharmacological activities including antioxidant activity, immunomodulatory activity, anti-tumor activity, glucose and lipid metabolism regulation, anti-radiation effect, detoxification effect, and viscera protection of R. roxbughii, as well as its development and utilization. The research status and existing problems of R. roxburghii development and quality control are also briefly introduced. This review ends with some suggestions on the perspectives and directions for future research and potential applications of R. roxbughii.

Comparative neuroprotective effects of Cerebrolysin, dexamethasone, and ascorbic acid on sciatic nerve injury model: Behavioral and histopathological study

Background

The majority of the suggested experimental modalities for peripheral nerve injury (PNI) result in varying degrees of recovery in animal models; however, there are not many reliable clinical pharmacological treatment models available. To alleviate PNI complications, research on approaches to accelerate peripheral nerve regeneration is encouraged. Cerebrolysin, dexamethasone, and ascorbic acid (vitamin C) drug models were selected in our study because of their reported curative effects of different mechanisms of action.

Methodology

A total of 40 adult male albino rats were used in this study. Sciatic nerve crush injury was induced in 32 rats, which were divided equally into four groups (model, Cerebrolysin, dexamethasone, and vitamin C groups) and compared to the sham group (n = 8). The sciatic nerve sensory and motor function regeneration after crushing together with gastrocnemius muscle histopathological changes were evaluated by the sciatic function index, the hot plate test, gastrocnemius muscle mass ratio, and immune expression of S100 and apoptosis cascade (BAX, BCL2, and BAX/BCL2 ratio).

Results

Significant improvement of the behavioral status and histopathological assessment scores occurred after the use of Cerebrolysin (as a neurotrophic factor), dexamethasone (as an anti-inflammatory), and vitamin C (as an antioxidant). Despite these seemingly concomitant, robust behavioral and pathological changes, vitamin C appeared to have the best results among the three main outcome measures. There was a positive correlation between motor and sensory improvement and also between behavioral and histopathological changes, boosting the effectiveness, and implication of the sciatic function index as a mirror for changes occurring on the tissue level.

Conclusion

Vitamin C is a promising therapeutic in the treatment of PNI. The sciatic function index (SFI) test is a reliable accurate method for assessing sciatic nerve integrity after both partial disruption and regrowth.

Electrochemical Nanosensors for Sensitization of Sweat Metabolites: From Concept Mapping to Personalized Health Monitoring

Sweat contains a broad range of important biomarkers, which may be beneficial for acquiring non-invasive biochemical information on human health status. Therefore, highly selective and sensitive electrochemical nanosensors for the non-invasive detection of sweat metabolites have turned into a flourishing contender in the frontier of disease diagnosis. A large surface area, excellent electrocatalytic behavior and conductive properties make nanomaterials promising sensor materials for target-specific detection. Carbon-based nanomaterials (e.g., CNT, carbon quantum dots, and graphene), noble metals (e.g., Au and Pt), and metal oxide nanomaterials (e.g., ZnO, MnO2, and NiO) are widely used for modifying the working electrodes of electrochemical sensors, which may then be further functionalized with requisite enzymes for targeted detection. In the present review, recent developments (2018-2022) of electrochemical nanosensors by both enzymatic as well as non-enzymatic sensors for the effectual detection of sweat metabolites (e.g., glucose, ascorbic acid, lactate, urea/uric acid, ethanol and drug metabolites) have been comprehensively reviewed. Along with this, electrochemical sensing principles, including potentiometry, amperometry, CV, DPV, SWV and EIS have been briefly presented in the present review for a conceptual understanding of the sensing mechanisms. The detection thresholds (in the range of mM-nM), sensitivities, linear dynamic ranges and sensing modalities have also been properly addressed for a systematic understanding of the judicious design of more effective sensors. One step ahead, in the present review, current trends of flexible wearable electrochemical sensors in the form of eyeglasses, tattoos, gloves, patches, headbands, wrist bands, etc., have also been briefly summarized, which are beneficial for on-body in situ measurement of the targeted sweat metabolites. On-body monitoring of sweat metabolites via wireless data transmission has also been addressed. Finally, the gaps in the ongoing research endeavors, unmet challenges, outlooks and future prospects have also been discussed for the development of advanced non-invasive self-health-care-monitoring devices in the near future.

Vitamin C Modes of Action in Calcium-Involved Signaling in the Brain

Vitamin C (ascorbic acid) is well known for its potent antioxidant properties, as it can neutralize ROS and free radicals, thereby protecting cellular elements from oxidative stress. It predominantly exists as an ascorbate anion and after oxidation to dehydroascorbic acid and further breakdown, is removed from the cells. In nervous tissue, a progressive decrease in vitamin C level or its prolonged deficiency have been associated with an increased risk of disturbances in neurotransmission, leading to dysregulation in brain function. Therefore, understanding the regulatory function of vitamin C in antioxidant defence and identification of its molecular targets deserves more attention. One of the key signalling ions is calcium and a transient rise in its concentration is crucial for all neuronal processes. Extracellular Ca²⁺ influx (through specific ion channels) or Ca²⁺ release from intracellular stores (endoplasmic reticulum, mitochondria) are precisely controlled. Ca²⁺ regulates the functioning of the CNS, including growth, development, myelin formation, synthesis of catecholamines, modulation of neurotransmission and antioxidant protection. A growing body of evidence indicates a unique role for vitamin C in these processes. In this short review, we focus on vitamin C in the regulation of calcium-involved pathways under physiological and stress conditions in the brain.

Dietary advice for patients with bowel-related conditions and malabsorption

PURPOSE

To explain the pathophysiology of kidney stone formation and appropriate dietary recommendations in inflammatory bowel diseases (IBD) such as ulcerative colitis (UC) and Crohn's disease (CD) and after bariatric surgery, focusing on the current literature.

METHODS

A narrative review methodology was performed. A literature search was conducted using PubMed, MEDLINE, and Google Scholar. Studies on the relationship between IBD or bariatric surgery and the risk of kidney stone formation were included.

RESULTS

Dietary composition has a critical role in urinary stone formation. Nutritional factors such as fluid intake, dietary protein, carbohydrates, oxalate, and calcium contribute to the risk of stone formation. Bowel-related malabsorptive conditions (IBD, after bariatric surgery, etc.) are associated with an increased risk of kidney stone formation due to metabolic and physiological changes such as hyperoxaluria, hypocitraturia, and decreased fluid intake or absorption. While the risk is lower in restrictive bariatric surgeries, the risk of kidney stone formation increases, especially after malabsorptive procedures. Dietary recommendations for these patients could profit alleviate urinary changes and reduce the risk of kidney stones.

CONCLUSION

Bowel-related malabsorptive conditions such as IBD and bariatric surgery are associated with an increased risk of kidney stones. Appropriate dietary recommendations can improve urinary metabolic changes and reduce kidney stone formation and the possibility of stone-related surgery.

Tracking the Biostimulatory Effect of Fractions from a Commercial Plant Protein Hydrolysate in Greenhouse-Grown Lettuce

Protein hydrolysate biostimulants are environmentally friendly options for the reduction of nitrogen input, but their plant growth-promoting mechanisms are still not completely unveiled. Here, to put the “signaling peptide theory” to the test, a greenhouse experiment was undertaken using low (1 mM) and optimal (8 mM) NO3-treated butterhead lettuce and three molecular fractions (PH1 (>10 kDa), PH2 (1−10 kDa) and PH3 (<10 kDa) fractions), in addition to the whole product Vegamin®: PH, in a randomized block design. PH1 and PH3 significantly increased fresh yield (+8%) under optimal (lighter leaves), but not under low (darker leaves) NO3 conditions. Total ascorbic acid, lutein and β-carotene increased with PH3, and disinapoylgentobiose and kaempferol-3-hydroxyferuloyl-sophorosie-7-glucoside content increased with PH (whole/fractions) treatments, particularly under low NO3 conditions. The complete hydrolysate and analyzed peptide fractions have differential biostimulatory effects, enhancing the growth and nutritional quality of lettuce.

ACE-Vitamin Index and Risk of Glaucoma: The SUN Project

BACKGROUND

Previous studies regarding antioxidant consumption and glaucoma have shown contradictory results. The aim of this study was to analyze the combined effect of the consumption of three vitamins (A, C and E) on the incidence of glaucoma in the SUN Project.

METHODS

For this study, 18,669 participants were included. The mean follow-up was 11.5 years. An index including vitamins A, C and E (ACE-Vitamin Index) was calculated. Vitamin intake was extracted from participants' dietary data and vitamin supplements, if taken. Information on glaucoma incidence was collected by previously validated self-reported questionnaires. The association between glaucoma and vitamin intake was assessed by repeated-measures Cox regression using multi-adjusted hazard ratios.

RESULTS

A total of 251 (1.3%) cases of glaucoma were detected. Participants with a higher ACE-Vitamin Index presented a reduced risk of glaucoma compared to participants with lower consumption (adjusted HR = 0.73; 95% CI, (0.55-0.98)). When each vitamin was analyzed individually, none of them had a significant protective effect. The protective effect of the ACE-Vitamin Index was higher in men and older participants (≥55 year).

CONCLUSIONS

The consumption of vitamins A, C and E considered separately do not seem to exert a protective effect against glaucoma, but when these vitamins are considered together, they are associated with a lower risk of glaucoma.

Insect Models in Nutrition Research

Insects are the most diverse organisms on earth, accounting for ~80% of all animals. They are valuable as model organisms, particularly in the context of genetics, development, behavior, neurobiology and evolutionary biology. Compared to other laboratory animals, insects are advantageous because they are inexpensive to house and breed in large numbers, making them suitable for high-throughput testing. They also have a short life cycle, facilitating the analysis of generational effects, and they fulfil the 3R principle (replacement, reduction and refinement). Many insect genomes have now been sequenced, highlighting their genetic and physiological similarities with humans. These factors also make insects favorable as whole-animal high-throughput models in nutritional research. In this review, we discuss the impact of insect models in nutritional science, focusing on studies investigating the role of nutrition in metabolic diseases and aging/longevity. We also consider food toxicology and the use of insects to study the gut microbiome. The benefits of insects as models to study the relationship between nutrition and biological markers of fitness and longevity can be exploited to improve human health.