CYBERMED LIFE - ORGANIC  & NATURAL LIVING

Vitamin C

Vitamin C, also known as ascorbic acid and L-ascorbic acid, is a vitamin found in food and used as a dietary supplement. The disease scurvy is prevented and treated with vitamin C-containing foods or dietary supplements. Evidence does not support use in the general population for the prevention of the common cold. There is, however, some evidence that regular use may shorten the length of colds. It is unclear if supplementation affects the risk of cancer, cardiovascular disease, or dementia. It may be taken by mouth or by injection.

Vitamin C is generally well tolerated. Large doses may cause gastrointestinal discomfort, headache, trouble sleeping, and flushing of the skin. Normal doses are safe during pregnancy. The United States Institute of Medicine recommends against taking large doses.

Vitamin C is an essential nutrient involved in the repair of tissue and the enzymatic production of certain neurotransmitters. It is required for the functioning of several enzymes and is important for immune system function. It also functions as an antioxidant. Foods containing vitamin C include citrus fruits, broccoli, Brussels sprouts, raw bell peppers, and strawberries. Prolonged storage or cooking may reduce vitamin C content in foods.

Vitamin C was discovered in 1912, isolated in 1928, and in 1933 was the first vitamin to be chemically produced. It is on the World Health Organization Model List of Essential Medicines, the most effective and safe medicines needed in a health system. Vitamin C is available as a generic medication and over-the-counter drug. In 2015, the wholesale cost in the developing world was less than US$0.01 per tablet. Partly for its discovery, Albert Szent-Györgyi and Walter Norman Haworth were awarded 1937 Nobel Prizes in Physiology and Medicine and Chemistry, respectively.

  • Daily intake of 100 mg ascorbic acid as urinary tract infection prophylactic agent during pregnancy.

    Abstract Title:

    Daily intake of 100 mg ascorbic acid as urinary tract infection prophylactic agent during pregnancy.

    Abstract Source:

    J Ethnopharmacol. 2009 Mar 18;122(2):320-6. Epub 2008 Dec 27. PMID: 17611821

    Abstract Author(s):

    Gonzalo Javier Ochoa-Brust, Alma Rosa Fernández, Gerson Jesús Villanueva-Ruiz, Raymundo Velasco, Benjamín Trujillo-Hernández, Clemente Vásquez

    Article Affiliation:

    Centro Universitario de Investigaciones Biomédicas y Facultad de Enfermería, Universidad de Colima, Colima, México.

    Abstract:

    OBJECTIVE:To evaluate the role a daily intake of 100 mg of ascorbic acid plays in urinary infection prophylaxis during pregnancy.

    METHODS AND MATERIALS:A single-blind clinical trial was carried out on pregnant women randomly assigned to the following treatment groups - Group A: oral treatment with ferrous sulphate (200 mg per day), folic acid (5 mg per day) and ascorbic acid (100 mg per day) for 3 months, and Group B: oral treatment with ferrous sulphate (200 mg per day) and folic acid (5 mg per day) for 3 months. All patients were clinically evaluated, and a urine culture was carried out each month for a period of 3 months. The chi(2) and odds ratio were used to compare effects with and without ascorbic acid, and statistical significance was considered at p<0.05.

    RESULTS:Global frequency of urinary infections was 25%. The presence of urinary infections in Group A (12.7%) was significantly lower than in Group B (29.1%), (p=0.03, OR =0.35, CI 95% =0.13-0.91).

    CONCLUSIONS:Daily intake of 100 mg of ascorbic acid played an important role in the reduction of urinary infections, improving the health level of the gestating women. We recommend additional vitamin C intake for pregnant women in populations which have a high incidence of bacteriuria and urinary infections.

  • Deficiency of vitamin D and vitamin C in the pathogenesis of bronchial asthma. 📎

    Abstract Title:

    Deficiency of vitamin D and vitamin C in the pathogenesis of bronchial asthma.

    Abstract Source:

    Bratisl Lek Listy. 2016 ;117(6):305-7. PMID: 27546360

    Abstract Author(s):

    E Ginter, V Simko

    Article Affiliation:

    E Ginter

    Abstract:

    Epidemiology of bronchial asthma (BA) indicates a marked paradox: rapid rise in the prevalence.Simultaneous decline in mortality is mostly related to improvement in the diagnosis and therapy. In many economically developed countries the BA affects more than 10 per cent of the population, while mortality related to this respiratory disorder is below 1/100,000. Factors favorably influencing mortality of BA include new more effective medications, decline in smoking and also improved nutrition, based on awareness of protective role of vitamins. Vitamin D deficiency has a number of biological effects that are potentially instrumental in the pathogenesis and severity of BA. Increased number of randomized, controlled, interventional studies is showing positive effects of vitamin D supplementation in pediatric and in adult BA. Oxidative stress is potentially an important pathogenic factor in the progression of BA. Vitamin C (ascorbic acid) belongs to the most effective nutritional antioxidants. By counteracting oxidants, reducing generation of reactive oxygen species, vitamin C may inhibit external attacks in the respiratory tract, thus modulating the development of BA (Fig. 2, Ref. 15).

  • Deoxycholic acid at neutral and acid pH, is genotoxic to oesophageal cells through the induction of ROS: The potential role of anti-oxidants in Barrett's oesophagus. 📎

    Abstract Title:

    Deoxycholic acid at neutral and acid pH, is genotoxic to oesophageal cells through the induction of ROS: The potential role of anti-oxidants in Barrett's oesophagus.

    Abstract Source:

    Carcinogenesis. 2007 Jan;28(1):136-42. Epub 2006 Aug 11. PMID: 16905748

    Abstract Author(s):

    Gareth J S Jenkins, Francis R D'Souza, Sinan H Suzen, Zak S Eltahir, Sally A James, James M Parry, Paul A Griffiths, John N Baxter

    Abstract:

    Bile acids are often refluxed into the lower oesophagus and are candidate carcinogens in the development of oesophageal adenocarcinoma. We show here that the secondary bile acid, deoxycholic acid (DCA), is the only one of the commonly refluxed bile acids tested here, to show genotoxicity, in terms of chromosome damage and mutation induction in the human p53 gene. This genotoxicity was apparent at both neutral and acidic pH, whilst there was a considerable increase in bile-induced toxicity at acidic pH. The higher levels of cell death and low cell survival rates at acidic pH may imply that acid bile exposure is toxic rather than carcinogenic, as dead cells do not seed cancer development. We also show that DCA (at neutral and acid pH) induced the release of reactive oxygen species (ROS) within the cytoplasm of exposed cells. We further demonstrate that the genotoxicity of DCA is ROS mediated, as micronucleus induction was significantly reduced when cells were treated with DCA + the anti-oxidant vitamin C.In conclusion, we show that DCA, is an effective genotoxin at both neutral and acidic pH. As bile acids like DCA can induce DNA damage at neutral pH, suppressing the acidity of the refluxate will not completely remove its carcinogenic potential. The genotoxicity of DCA is however, ROS dependent, hence anti-oxidant supplementation, in addition to acid suppression may block DCA driven carcinogenesis in Barrett's patients.

  • Depletion of ascorbic acid impairs NK cell activity against ovarian cancer in a mouse model.

    Abstract Title:

    Depletion of ascorbic acid impairs NK cell activity against ovarian cancer in a mouse model.

    Abstract Source:

    Immunobiology. 2012 Jan 2. Epub 2012 Jan 2. PMID: 22306178

    Abstract Author(s):

    Jee-Eun Kim, Hang-Sun Cho, Hoon-Shik Yang, Da-Jung Jung, Seung-Woo Hong, Chien-Fu Hung, Wang Jae Lee, Daejin Kim

    Article Affiliation:

    Department of Anatomy, Chung-Ang University, College of Medicine, Seoul, Republic of Korea; Department of Anatomy, Seoul National University, College of Medicine, Seoul, Republic of Korea.

    Abstract:

    Ascorbic acid (Vitamin C) administration has been used to prevent infectious diseases in public or as a therapeutic agent by the physicians in treatment of several diseases. Ascorbic acid is also involved in immune cell functions and immune responses, although the mechanisms by which it exerts effects on immune cells against cancer cells are not fully understood at the normal plasma level. In this study, we used the mice lacking l-gulono-γ-lactone oxidase (Gulo), the enzyme required for the biosynthesis of ascorbic acid, to characterize the effects of ascorbic acid on NK cell cytotoxicity against ovarian cancer cells, MOSECs (murine ovarian surface epithelial cells). Gulo(-/-) mice depleted of ascorbic acid survived for a shorter time than the normal control or Gulo(-/-) mice supplemented with ascorbic acid after tumor challenge regardless of treatment with IL-2. CD69 and NKG2D expression was clearly reduced in NK cells isolated from mice depleted of ascorbic acid as compared to that in the normal control and the mice supplemented with ascorbic acid. We also observed that IFN-γ secretion by NK cells isolated from Gulo(-/-) mice depleted of ascorbic acid was decreased after NK cells were co-cultured with MOSECs. Furthermore, the mRNA expression of perforin and granzyme B genes was also significantly decreased in NK cells isolated from mice depleted of ascorbic acid. Taken together, our results suggest that ascorbic acid at the normal plasma concentration has an essential role in maintaining the NK cytotoxicity against cancer cells.

  • Depletion of L-ascorbic acid alternating with its supplementation in the treatment of patients with acute myeloid leukemia or myelodysplastic syndromes.

    Abstract Title:

    Depletion of L-ascorbic acid alternating with its supplementation in the treatment of patients with acute myeloid leukemia or myelodysplastic syndromes.

    Abstract Source:

    Eur J Haematol. 2009 Mar 5. PMID: 19284416

    Abstract Author(s):

    Chan H Park, Bruce F Kimler, Seong Yoon Yi, Se Hoon Park, Kihyun Kim, Chul Won Jung, Sun Hee Kim, Eun Ryung Lee, Miyong Rha, Seonwoo Kim, Mary H Park, Sook J Lee, Hye K Park, Mark H Lee, Sung Soo Yoon, Yoo Hong Min, Bong Seog Kim, Jeong-A Kim, Won Seog Kim

    Abstract:

    Purpose: L-ascorbic acid (LAA) modifies the in vitro growth of leukemic cells from approximately 50% of patients with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS). To test the hypothesis that depletion of LAA, alternating with supplementation to prevent scurvy, would provide therapeutic benefit, a single-arm pilot trial was conducted (ClinicalTrials.gov identifier: NCT00329498). Experimental results: During depletion phase, patients with refractory AML or MDS were placed on a diet deficient in LAA; during supplementation phase, patients received daily intravenous administration of LAA. An in vitro assay was performed pre-therapy for LAA sensitivity of leukemic cells from individual patients. Results: Of 18 patients enrolled, 8 of 16 evaluable patients demonstrated a clinical response. Responses were obtained during depletion (4 patients) as well as during supplementation (5 patients) but at a pharmacologic plasma level achievable only with intravenous administration. Of nine patients for whom the in vitro assay indicated their leukemic cells were sensitive to LAA, seven exhibited a clinical response; compared to none of six patients that were insensitive to LAA. Conclusions: The clinical benefit, along with a conspicuous absence of significant adverse events, suggests that further testing of LAA depletion alternating with pharmacologic dose intravenous supplementation in patients with these and other malignancies is warranted.

  • Diagnosis and treatment of rosacea. 📎

    Abstract Title:

    Diagnosis and treatment of rosacea.

    Abstract Source:

    J Am Board Fam Pract. 2002 May-Jun;15(3):214-7. PMID: 12038728

    Abstract Author(s):

    Aaron F Cohen, Jeffrey D Tiemstra

    Abstract:

    BACKGROUND: Rosacea is a common skin disorder affecting middle-aged and older adults. Many patients mistakenly assume that early rosacea is normally aging skin and are not aware that effective treatments exist to prevent progression to permanent disfiguring skin changes. METHODS: The medical literature was reviewed on the pathophysiology, diagnosis, and treatment of rosacea. MEDLINE was searched using the key search terms "rosacea," "rhinophyma," "metronidazole," "Helicobacter pylori," and "facial redness." RESULTS AND CONCLUSIONS: Rosacea is easily diagnosed by physician observation, and physicians should initiate discussion of rosacea treatment with patients. Effective treatment of rosacea includes avoidance of triggers, topical and oral antibiotic therapy, both topical and oral retinoid therapy, topical vitamin C therapy, and cosmetic surgery.

  • Dietary carotenoids, vitamins C and E, and risk of cataract in women: a prospective study. 📎

    Abstract Title:

    Dietary carotenoids, vitamins C and E, and risk of cataract in women: a prospective study.

    Abstract Source:

    Arch Ophthalmol. 2008 Jan;126(1):102-9. PMID: 18195226

    Abstract Author(s):

    William G Christen, Simin Liu, Robert J Glynn, J Michael Gaziano, Julie E Buring

    Abstract:

    OBJECTIVE: To examine in prospective data the relation between dietary intake of carotenoids and vitamins C and E and the risk of cataract in women. DESIGN: Dietary intake was assessed at baseline in 39,876 female health professionals by using a detailed food frequency questionnaire. A total of 35,551 women provided detailed information on antioxidant nutrient intake from food and supplements and were free of a diagnosis of cataract. The main outcome measure was cataract, defined as an incident, age-related lens opacity responsible for a reduction in best-corrected visual acuity in the worse eye to 20/30 or worse based on self-report confirmed by medical record review. RESULTS: A total of 2031 cases of incident cataract were confirmed during a mean of 10 years of follow-up. Comparing women in the extreme quintiles, the multivariate relative risk of cataract was 0.82 (95% confidence interval, 0.71-0.95; test for trend, P = .04) for lutein/zeaxanthin and 0.86 (95% confidence interval, 0.74-1.00; test for trend, P = .03) for vitamin E from food and supplements. CONCLUSION: In these prospective observational data from a large cohort of female health professionals, higher dietary intakes of lutein/zeaxanthin and vitamin E from food and supplements were associated with significantly decreased risks of cataract.

  • Dietary Intake of Antioxidant Vitamins and Carotenoids and Risk of Developing Active Tuberculosis in a Prospective Population-based Cohort.

    Abstract Title:

    Dietary Intake of Antioxidant Vitamins and Carotenoids and Risk of Developing Active Tuberculosis in a Prospective Population-based Cohort.

    Abstract Source:

    Am J Epidemiol. 2017 May 18. Epub 2017 May 18. PMID: 28520939

    Abstract Author(s):

    Avril Z Soh, Cynthia B E Chee, Yee-Tang Wang, Jian-Min Yuan, Woon-Puay Koh

    Article Affiliation:

    Avril Z Soh

    Abstract:

    Antioxidants may protect against oxidative stress, which is associated with tuberculosis disease. However, direct evidence for the protective association between dietary antioxidants and tuberculosis incidence in humans has been lacking. The relation between intake of antioxidant vitamins (A, C, D, E) and individual carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein) and tuberculosis incidence was examined in the Singapore Chinese Health Study, a prospective cohort of 63,257 adults 45-74 years old enrolled during 1993-1998. Baseline intake of these antioxidants was estimated using a validated semi-quantitative food-frequency questionnaire including use of dietary supplements. After an average of 16.9 years follow-up, 1,186 incident active tuberculosis cases were identified among cohort participants. Compared to the lowest quartile, reduced active tuberculosis risk was observed for the highest quartile of vitamin A (hazard ratio = 0.71, 95% confidence interval: 0.59-0.85; P-trend < 0.01) and β-carotene (hazard ratio = 0.76, 95% confidence interval: 0.63-0.91; P-trend < 0.01), regardless of smoking status. Lower tuberculosis risk was seen for vitamin C among current smokers only. Other vitamins and carotenoids were not associated with tuberculosis risk. These results suggest vitamin C may reduce tuberculosis risk among current smokers by ameliorating oxidative stress, while vitamin A and β-carotene may have additional anti-mycobacterial properties.

  • Dietary intake of selected micronutrients and the risk of pancreatic cancer: an Italian case-control study📎

    Abstract Title:

    Dietary intake of selected micronutrients and the risk of pancreatic cancer: an Italian case-control study.

    Abstract Source:

    Ann Oncol. 2010 Jun 7. Epub 2010 Jun 7. PMID: 20530201

    Abstract Author(s):

    F Bravi, J Polesel, C Bosetti, R Talamini, E Negri, L Dal Maso, D Serraino, C La Vecchia

    Article Affiliation:

    Department of Epidemiology, Mario Negri Institute for Pharmacological Research, Milan.

    Abstract:

    Objective: Several studies have shown an inverse relation between vegetable and fruit intake and pancreatic cancer, but no specific beneficial component of such foods has been consistently identified. We considered the role of 15 selected vitamins and carotenoids and 6 minerals on pancreatic cancer risk in an Italian case-control study. METHODS: Subjects were 326 patients with incident pancreatic cancer and 652 controls, admitted to the same hospitals as cases for acute conditions. Micronutrient computation was based on a validated and reproducible food-frequency questionnaire. We estimated the odds ratios (OR) and confidence intervals (CI) using conditional logistic regression models, adjusted for various confounding factors and for energy intake, according to the residual model. RESULTS: Comparing the highest to the lowest quintile of intake, the OR were 0.60 (95% CI 0.36-0.98) for vitamin E, 0.44 (95% CI 0.27-0.73) for vitamin C, 0.56 (95% CI 0.34-0.93) for folate, and 0.57 (95% CI 0.35-0.92) for potassium. No significant inverse associations were observed for alpha-carotene (OR = 0.69, 95% CI 0.43-1.12), beta-carotene (OR = 0.64, 95% CI 0.39-1.06), and beta-cryptoxanthin (OR = 0.66, 95% CI 0.39-1.09). No relation was found for other micronutrients considered. CONCLUSION: Our findings support a favorable role of vitamins E and C, selected carotenoids, and folate on pancreatic carcinogenesis.

  • Dietary supplement use and risk of neoplastic progression in esophageal adenocarcinoma: a prospective study. 📎

    Abstract Title:

    Dietary supplement use and risk of neoplastic progression in esophageal adenocarcinoma: a prospective study.

    Abstract Source:

    Nutr Cancer. 2008;60(1):39-48. PMID: 18444134

    Abstract Author(s):

    Linda M Dong, Alan R Kristal, Ulrike Peters, Jeannette M Schenk, Carissa A Sanchez, Peter S Rabinovitch, Patricia L Blount, Robert D Odze, Kamran Ayub, Brian J Reid, Thomas L Vaughan

    Article Affiliation:

    Cancer Prevention Program, Fred Hutchinson Cancer Research Center, and Department of Epidemiology, University of Washington, Seattle, WA 98109, USA.

    Abstract:

    The incidence of esophageal adenocarcinoma (EA) and its precursor condition, Barrett's esophagus, has risen rapidly in the United States for reasons that are not fully understood. Therefore, we evaluated the association between use of supplemental vitamins and minerals and risk of neoplastic progression of Barrett's esophagus and EA. The Seattle Barrett's Esophagus Program is a prospective study based on 339 men and women with histologically confirmed Barrett's esophagus. Participants underwent baseline and periodic follow-up exams, which included endoscopy and self-administered questionnaires on diet, supplement use, and lifestyle characteristics. Use of multivitamins and 4 individual supplements was calculated using time-weighted averages of reported use over the observational period. Cox proportional-hazards models were used to calculate hazard ratios (HR) for each endpoint: EA, tetraploidy, and aneuploidy. During a mean follow-up of 5 yr, there were 37 cases of EA, 42 cases of tetraploidy, and 34 cases of aneuploidy. After controlling for multiple covariates including diet, nonsteroidal anti-inflammatory drug use, obesity, and smoking, participants who took 1 or more multivitamin pills/day had a significantly decreased risk of tetraploidy [HR = 0.19; 95% confidence interval (CI) = 0.08-0.47) and EA (HR = 0.38; 95% CI = 0.15-0.99] compared to those not taking multivitamins. Significant inverse associations were also observed between risk of EA and supplemental vitamin C (>or = 250 mg vs. none: HR = 0.25; 95% CI = 0.11-0.58) and vitamin E (>or = 180 mg vs. none: HR = 0.25; 95% CI = 0.10-0.60). In this cohort study, use of multivitamins and single antioxidant supplements was associated with a significantly reduced risk of EA and markers of neoplastic progression among individuals with Barrett's esophagus.

  • Dietary supplementation with resveratrol reduces plaque pathology in a transgenic model of Alzheimer's disease. 📎

    Abstract Title:

    Dietary supplementation with resveratrol reduces plaque pathology in a transgenic model of Alzheimer's disease.

    Abstract Source:

    Br J Pharmacol. 2010 Dec 30. Epub 2010 Dec 30. PMID: 19041676

    Abstract Author(s):

    Saravanan S Karuppagounder, John T Pinto, Hui Xu, Huan-Lian Chen, M Flint Beal, Gary E Gibson

    Article Affiliation:

    Department of Neurology and Neurosciences, Weill Medical College of Cornell University, Burke Medical Research Institute, 785 Mamaroneck Ave., White Plains, NY 10605, United States.

    Abstract:

    Resveratrol, a polyphenol found in red wine, peanuts, soy beans, and pomegranates, possesses a wide range of biological effects. Since resveratrol's properties seem ideal for treating neurodegenerative diseases, its ability to diminish amyloid plaques was tested. Mice were fed clinically feasible dosages of resveratrol for forty-five days. Neither resveratrol nor its conjugated metabolites were detectable in brain. Nevertheless, resveratrol diminished plaque formation in a region specific manner. The largest reductions in the percent area occupied by plaques were observed in medial cortex (-48%), striatum (-89%) and hypothalamus (-90%). The changes occurred without detectable activation of SIRT-1 or alterations in APP processing. However, brain glutathione declined 21% and brain cysteine increased 54%. The increased cysteine and decreased glutathione may be linked to the diminished plaque formation. This study supports the concept that onset of neurodegenerative disease may be delayed or mitigated with use of dietary chemo-preventive agents that protect against beta-amyloid plaque formation and oxidative stress.

  • Dietary vitamin C and bone mineral density in postmenopausal women in Washington State, USA. 📎

    Abstract Title:

    Dietary vitamin C and bone mineral density in postmenopausal women in Washington State, USA.

    Abstract Source:

    J Epidemiol Community Health. 1997 Oct ;51(5):479-85. PMID: 9425455

    Abstract Author(s):

    S G Leveille, A Z LaCroix, T D Koepsell, S A Beresford, G Van Belle, D M Buchner

    Article Affiliation:

    Center for Health Studies, Group Health Cooperative of Puget Sound, Seattle, Washington, USA.

    Abstract:

    STUDY OBJECTIVE:To examine the relationship between dietary vitamin C and hip bone mineral density (BMD) in postmenopausal women.

    DESIGN:This was a cross sectional study using retrospective diet and vitamin supplement data.

    SETTING:The Seattle area of Washington State.

    PARTICIPANTS:Screenees for a clinical trial of a drug to prevent osteoporotic fractures; 1892 women aged 55-80 years who had hip bone densitometry and osteoporosis risk factor information.

    MAIN RESULTS:Mean energy adjusted dietary intake of vitamin C was 113 mg/day; including supplement use, mean intake was 407 mg/day. There were no differences in BMD according to diet-only vitamin C intake or combined dietary and supplemental vitamin C intake. Longer duration of vitamin C supplement use was associated with higher BMD in women who had not used oestrogen replacement therapy (trend p = 0.02) and among women aged 55-64 years (trend p = 0.01). Women aged 55-64 years who used vitamin C supplements for>or = 10 years had a higher BMD than non-users aged 55-64 years (multivariate adjusted mean BMD 0.699 (0.017) g/cm2 versus 0.655 (0.007) g/cm2, p = 0.02). Benefits were not evident in older age groups or in women who had used oestrogen in the past. Frequent intake of foods rich in vitamin C was not associated with BMD.

    CONCLUSION:There was no evidence that vitamin C from the diet was associated with BMD, although long term use of vitamin C supplements was associated with a higher BMD in the early postmenopausal years and among never users of oestrogen.

  • Dietary vitamin C intake protects against COPD: the Korea National Health and Nutrition Examination Survey in 2012. 📎

    Abstract Title:

    Dietary vitamin C intake protects against COPD: the Korea National Health and Nutrition Examination Survey in 2012.

    Abstract Source:

    Int J Chron Obstruct Pulmon Dis. 2016 ;11:2721-2728. Epub 2016 Oct 31. PMID: 27843308

    Abstract Author(s):

    Hye Jung Park, Min Kwang Byun, Hyung Jung Kim, Jae Yeol Kim, Yu-Il Kim, Kwang-Ha Yoo, Eun Mi Chun, Ji Ye Jung, Sang Haak Lee, Chul Min Ahn

    Article Affiliation:

    Hye Jung Park

    Abstract:

    BACKGROUND:Vitamin C, as an antioxidant, has recently been suggested to provide protection against COPD; however, only few national cohort studies have investigated these effects. We aimed to confirm the protective effects of vitamin C against COPD in Korean patients.

    PATIENTS AND METHODS:We analyzed the data of 3,283 adults aged≥40 years (representing 23,541,704 subjects) who underwent pulmonary function tests and responded to questionnaires on smoking history and vitamin C intake, with stratification variables and sampling weight designated by the Korea 2012 National Health and Nutrition Examination Survey.

    RESULTS:Among all the subjects, 512 (representing 3,459,679 subjects; 15.6%) were diagnosed as having COPD based on pulmonary function test results. Male gender, old age, residence in suburban/rural regions, low household income, low educational level, an occupation in agriculture or fisheries, and heavy smoking were significantly associated with COPD. Low intake of nutrients, including potassium, vitamin A, carotene, retinol, and vitamin C, was significantly associated with COPD. The prevalence of COPD in heavy smokers with the lowest quartile (Q1,<48.50 mg; 63.0%) and low-middle quartile (Q2, 48.50-84.38 mg; 56.4%) of vitamin C intake was significantly higher than that in subjects with the high-middle quartile (Q3, 84.38-141.63 mg; 29.5%) and highest quartile (Q4,>141.63 mg; 32.6%) of vitamin C intake (P=0.015). In multivariate analysis, male gender, old age, heavy smoking, and a low intake of vitamin C were significant independent risk factors for COPD. A significant reduction of 76.7% in COPD risk was observed with a Q3 vitamin C intake compared to Q1 vitamin C intake (odds ratio, 0.233; 95% confidence interval, 0.094-0.576) in heavy smokers.

    CONCLUSION:This large-scale national study suggests that dietary vitamin C provides protection against COPD, independent of smoking history, in the general Korean population.

  • Dietary Vitamin C Intake Reduces the Risk of Type 2 Diabetes in Chinese Adults: HOMA-IR and T-AOC as Potential Mediators. 📎

    Abstract Title:

    Dietary Vitamin C Intake Reduces the Risk of Type 2 Diabetes in Chinese Adults: HOMA-IR and T-AOC as Potential Mediators.

    Abstract Source:

    PLoS One. 2016;11(9):e0163571. Epub 2016 Sep 29. PMID: 27685994

    Abstract Author(s):

    Chunling Zhou, Lixin Na, Ruiqi Shan, Yu Cheng, Ying Li, Xiaoyan Wu, Changhao Sun

    Article Affiliation:

    Chunling Zhou

    Abstract:

    Despite growing interest in the protective role that dietary antioxidant vitamins may have in the development of type 2 diabetes (T2D), little epidemiological evidence is available in non-Western populations especially about the possible mediators underlying in this role. The present study aimed to investigate the association of vitamin C and vitamin E intakes with T2D risk in Chinese adults and examine the potential mediators. 178 incident T2D cases among 3483 participants in the Harbin People Health Study (HPHS), and 522 newly diagnosed T2D among 7595 participants in the Harbin Cohort Study on Diet, Nutrition and Chronic Non-communicable Diseases (HDNNCDS) were studied. In the multivariable-adjusted logistics regression model, the relative risks (RRs) were 1.00, 0.75, and 0.76 (Ptrend = 0.003) across tertiles of vitamin C intake in the HDNNCDS, and this association was validated in the HPHS with RRs of 1.00, 0.47, and 0.46 (Ptrend = 0.002). The RRs were 1.00, 0.72, and 0.76 (Ptrend = 0.039) when T2D diagnosed by haemoglobin A1c in the HDNNCDS. The mediation analysis discovered that insulin resistance (indicated by homeostasis model assessment) and oxidative stress (indicated by plasma total antioxidative capacity) partly mediated this association. But no association was evident between vitamin E intake and T2D. In conclusion, our research adds further support to the role of vitamin C intake in reducing the development of T2D in the broader population studied. The results also suggested that this association was partly mediated by inhibiting or ameliorating oxidative stress and insulin resistance.

  • Does nutritional status affect benzene induced toxicity and/or leukemia?

    Abstract Title:

    Does nutritional status affect benzene induced toxicity and/or leukemia?

    Abstract Source:

    Med Hypotheses. 1980 May;6(5):535-44. PMID: 7412643

    Abstract Author(s):

    E J Calabrese

    Abstract:

    Despite similar levels and duration of benzene exposure, toxicological responses of workers are highly variable. Given a similar degree of exposure, why do some workers remain apparently unaffected, while others develop alterations of the hemopoietic system? It is hypothesized that inadequate nutritional status of possibly several nutrients including iron, selenium, methionine and ascorbic acid may enhance susceptibility to adverse effects caused by benzene.

  • Doxorubicin induced nitrosative stress is mitigated by Vitamin C via the modulation of nitric oxide synthases. 📎

    Abstract Title:

    Doxorubicin induced nitrosative stress is mitigated by Vitamin C via the modulation of nitric oxide synthases.

    Abstract Source:

    Am J Physiol Cell Physiol. 2017 Jan 18:ajpcell.00356.2016. Epub 2017 Jan 18. PMID: 28100487

    Abstract Author(s):

    Gauri Akolkar, Ashim K Bagchi, Prathapan Ayyappan, Davinder S Jassal, Pawan K Singal

    Article Affiliation:

    Gauri Akolkar

    Abstract:

    An increase in oxidative stress is suggested to be the main cause in Doxorubicin (Dox) -induced cardiotoxicity. However, there is now evidence that activation of inducible nitric oxide synthase (iNOS) and nitrosative stress are also involved. The role of Vitamin C (Vit C) in the regulation of nitric oxide synthase (NOS) and reduction of nitrosative stress in Dox-induced cardiotoxicity is unknown. The present study investigated the effects of Vit C in the mitigation of Dox-induced changes in the levels of nitric oxide (NO), NOS activity, protein expression of NOS isoforms and nitrosative stress as well as cytokines TNFα and IL-10 in isolated cardiomyocytes. Cardiomyocytes isolated from adult Sprague Dawley rats were segregated into four groups: i) control; ii) Vit C (25 µM); iii) Dox (10 µM); and iv) Vit C + Dox. Dox caused significant increase in the generation of superoxide radical (O2(-)), peroxynitrite andNO and these effects of Dox were blunted by Vit C. Dox increased the expression of iNOS and altered protein expression as well as activation of endothelial NOS (eNOS). These changes were prevented by Vit C. Dox-induced increase in the ratio of monomeric/dimeric eNOS, promoting the production of O2(-), which was prevented by Vit C by increasing the stability of dimeric form of eNOS. Vit C protected against Dox-induced increase in TNFα as well as a reduction in IL-10. These results suggest that Vit C provides cardioprotection by reducing oxidative/nitrosative stress and inflammation via a modulation of Dox-induced increase in the NO levels and NOS activity.

  • Dual Role of Vitamin C on the Neuroinflammation Mediated Neurodegeneration and Memory Impairments in Colchicine Induced Rat Model of Alzheimer Disease.

    Abstract Title:

    Dual Role of Vitamin C on the Neuroinflammation Mediated Neurodegeneration and Memory Impairments in Colchicine Induced Rat Model of Alzheimer Disease.

    Abstract Source:

    J Mol Neurosci. 2016 Sep 24. Epub 2016 Sep 24. PMID: 27665568

    Abstract Author(s):

    Susmita Sil, Tusharkanti Ghosh, Pritha Gupta, Rupsa Ghosh, Syed N Kabir, Avishek Roy

    Article Affiliation:

    Susmita Sil

    Abstract:

    The neurodegeneration in colchicine induced AD rats (cAD) is mediated by cox-2 linked neuroinflammation. The importance of ROS in the inflammatory process in cAD has not been identified, which may be deciphered by blocking oxidative stress in this model by a well-known anti-oxidant vitamin C. Therefore, the present study was designed to investigate the role of vitamin C on colchicine induced oxidative stress linked neuroinflammation mediated neurodegeneration and memory impairments along with peripheral immune responses in cAD. The impairments of working and reference memory were associated with neuroinflammation and neurodegeneration in the hippocampus of cAD. Administration of vitamin C (200 and 400 mg/kg BW) in cAD resulted in recovery of memory impairments, with prevention of neurodegeneration and neuroinflammation in the hippocampus. The neuroinflammation in the hippocampus also influenced the peripheral immune responses and inflammation in the serum of cAD and all of these parameters werealso recovered at 200 and 400 mg dose of vitamin C. However, cAD treated with 600 mg dose did not recover but resulted in increase of memory impairments, neurodegeneration and neuroinflammation in hippocampus along with alteration of peripheral immune responses in comparison to cAD of the presentstudy. Therefore, the present study showed that ROS played an important role in the colchicine induced neuroinflammation linked neurodegeneration and memory impairments along with alteration of peripheral immune responses. It also appears from the results that vitamin C at lower doses showed anti-oxidant effect and at higher dose resulted in pro-oxidant effects in cAD.

  • Echinacea purpurea along with zinc, selenium and vitamin C to alleviate exacerbations of chronic obstructive pulmonary disease: results from a randomized controlled trial.

    Abstract Title:

    Echinacea purpurea along with zinc, selenium and vitamin C to alleviate exacerbations of chronic obstructive pulmonary disease: results from a randomized controlled trial.

    Abstract Source:

    J Clin Pharm Ther. 2010 Nov 10. Epub 2010 Nov 10. PMID: 21062330

    Abstract Author(s):

    F Isbaniah, W H Wiyono, F Yunus, A Setiawati, U Totzke, M A Verbruggen

    Article Affiliation:

    Department of Pulmonology and Respiratory Medicine, Faculty of Medicine, University of Indonesia, Persahabatan Hospital, Jakarta, Indonesia Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Indonesia, Persahabatan Hospital, Jakarta, Indonesia Totzke Scientific, Chancy/Geneva, Switzerland Frutarom Switzerland Ltd, Wädenswil, Switzerland.

    Abstract:

    What is known and objective:  Upper respiratory tract infections (URTI) frequently cause exacerbations of chronic-obstructive pulmonary disease (COPD). Stimulation of the innate immune system may provide an early defence against such infections. The objective of this study was to determine whether Echinacea purpurea (EP) along with micronutrients may alleviate COPD exacerbations caused by acute URTI. Methods:  This was a double-blind, randomized, placebo-controlled trial in COPD patients with acute URTI. Patients were given ciprofloxacin for 7 days and additionally one tablet per day of EP, of EP along with zinc, selenium and ascorbic acid (EP+), or of placebo until day 14. Serum levels of TNF α and interleukins 1β, 6 and 10 were measured before and after treatment. Until week 4 post-end of treatment, all patients had to daily report on COPD symptoms in diaries. Results and Discussion:  In total, 108 mostly male patients with a mean age of 65·8 years (40-81 years) were enrolled. Patients of the three treatment arms did not vary significantly in baseline characteristics. EP+, but not EP resulted in significantly less severe and shorter exacerbation episodes following URTI as compared with placebo suggesting a synergistic effect of Echinacea and micronutrients. Large variations in biomarkers in-between and within groups were unrelated to treatment. Study medication was safe and well tolerated with overall 15 adverse events one of which was serious. Among those, sleeping disorders were mostfrequent and likely related to the underlying disease. What is new and Conclusion:  The combination of EP, zinc, selenium and vitamin C may alleviate exacerbation symptoms caused by URTI in COPD. Further studies are warranted to investigate the interactions among Echinacea, zinc, selenium and vitamin C.

  • Effect and proposed mechanism of vitamin C modulating amino acid regulation of autophagic proteolysis.

    Abstract Title:

    Effect and proposed mechanism of vitamin C modulating amino acid regulation of autophagic proteolysis.

    Abstract Source:

    Biochimie. 2017 Aug 10. Epub 2017 Aug 10. PMID: 28804003

    Abstract Author(s):

    Md Razaul Karim, Motoni Kadowaki

    Article Affiliation:

    Md Razaul Karim

    Abstract:

    Autophagy is an intracellular bulk degradation process, induced under nutrient starvation. Failure of autophagy has been recognized as a contributor to aging and multiple age related neurodegenerative diseases. Improving autophagy is a beneficial anti-aging strategy, however very few physiological regulators have been identified. Here, we demonstrate that vitamin C is a nutritional stimulator of autophagy. Supplementation of fresh hepatocytes with vitamin C increased autophagic proteolysis significantly in the presence of amino acids in a dose- and time-dependent manner, although no effect was observed in the absence of amino acids. In addition, inhibitor studies with 3-methyladenine, chloroquine, leupeptin andβ-lactone confirmed that vitamin C is active through the lysosomal autophagy and not the proteasome pathway. Furthermore, the autophagy marker LC3 protein was significantly increased by vitamin C, suggesting its possible site of action is at the formation step. Both the reduced (ascorbic acid, AsA)and oxidized form (dehydroascorbic acid, DHA) of vitamin C exhibited equal enhancing effect, indicating that the effect does not depend on the anti-oxidation functionality of vitamin C. To understand the mechanism, we established that the effective dose (50 μM) was 15× lower than the intracellular content suggesting these would be only a minor influx from the extracellular pool. Moreover, transporter inhibitor studies in an AsA deficient ODS model rat revealed more accurately that the enhancing effect on autophagic proteolysis still existed, even though the intracellular influx of AsA wasblocked. Taken together, these results provide evidence that vitamin C can potentially act through extracellular signaling.

  • Effect of a novel dietary supplement on skin aging in post-menopausal women.

    Abstract Title:

    Effect of a novel dietary supplement on skin aging in post-menopausal women.

    Abstract Source:

    Eur J Clin Nutr. 2006 Oct;60(10):1201-6. Epub 2006 May 3. PMID: 16670692

    Abstract Author(s):

    G R Lange Skovgaard, A S Jensen, M L Sigler

    Abstract:

    OBJECTIVE: The aim of the present study was to quantify the effects on skin in post-menopausal women of a novel dietary supplement (Imedeen Prime Renewal) that contained soy extract, fish protein polysaccharides, extracts from white tea, grape seed and tomato, vitamins C and E as well as zinc and chamomile extract. DESIGN: The study was a 6-month double blind, placebo controlled, randomized study on healthy post-menopausal females. SETTING: The study was performed at a commercial Contract Research Organisation (TJ Stephens & Associates Inc., TX, USA). INTERVENTIONS: Two tablets of Imedeen Prime Renewal or placebo were given twice daily for 6 months. SUBJECTS: Thirty-eight (active group) and 42 (placebo group) subjects completed the study out of 100. RESULTS: Clinical grading showed that the active group had a significantly greater improvement (P < 0.05) compared to placebo for the face after 6 months treatment for: forehead, periocular and perioral wrinkles, mottled pigmentation, laxity, sagging, under eye dark circles and overall apperance; skin on the décolletage after 2, 3 and 6 months treatment and skin on the hand after 3 and 6 months treatment. Photo evaluation showed that the active group had a significantly greater improvement (P < 0.05) on the face after 3 and 6 months for several parameters. Ultrasound measurements showed that the active group had a significantly greater improvement (P < 0.0001) for density measurements after 6 months treatment. CONCLUSION: In summary, this novel dietary supplement, Imedeen Prime Renewal, provides improved condition, structure and firmness of the skin in post-menopausal women after 6 months.

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