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Recent Developments in Therapies and Strategies Against COVID-19
Published in Hanadi Talal Ahmedah, Muhammad Riaz, Sagheer Ahmed, Marius Alexandru Moga, The Covid-19 Pandemic, 2023
Misbah Hameed, M. Zia-Ul-Haq, Marius Moga
Ascorbic acid is one of the essential nutrients that plays many significant roles. Vitamin C in the form of ascorbate is very important as it performs various physiological functions. It serves as an enzyme substrate, a cofactor, and an electron donor. It performs various functions which include the synthesis of carnitine, collagen, neurotransmitters, and catabolism of tyrosine and the metabolism of microsome. It has the ability to neutralize free radicals, function as a potent antioxidant and assist to reverse cellular damage [64]. Ascorbic acid can be effective antiviral as well especially against influenza viruses. It is suggested that vitamin C enhances the maturation of T lymphocytes which are required against viral infections. It also inhibits free radicals’ production and cytokines remodulation needed for systemic inflammatory syndrome.
Nutrition: Diet Therapy and Nutritional Supplements
Published in Paloma Tejero, Hernán Pinto, Aesthetic Treatments for the Oncology Patient, 2020
Vitamin C is a water-soluble vitamin, also known as ascorbic acid. It is stored in the body for only a short time and is eliminated in small amounts through the urine. It is an essential nutrient that in normal physiological concentrations has oxidation-reduction (redox) functions.
Nutritional Disorders/Alternative Medicine
Published in Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss, Understanding Medical Terms, 2020
Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss
Ascorbic acid (C) deficiency results in impaired synthesis of collagen, the major protein of the white fibers of connective tissue, bone, and cartilage. Symptoms include joint pain, anemia, delayed wound healing, and increased risk of infection. The severe form of deficiency is scurvy with hemorrhages in the skin, gum inflammation with loosening of the teeth, muscle weakness, and joint pain. The disorder is no longer common in the general population. It is seen in areas of urban poverty, during the first year of life when infant formulas are not supplemented with vitamin C, and occasionally in middle age to elderly males because of poor diet. Symptoms of deficiency occur after discontinuation of large doses of vitamin C; therefore, dosages should be tapered.
A novel homozygous loss-of-function variant in SOD1 causing progressive spastic tetraplegia and axial hypotonia
Published in Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration, 2023
Arman Çakar, Emre Pekbilir, Serdar Ceylaner, Hacer Durmuş, Esra Battaloğlu, Umut Şahin, Yeşim Parman
Real-time PCR analyses employing a primer pair that targets exon 3 through exon 5 of the SOD1 transcript indicated a total loss of SOD1 mRNA expression in the index patient, and heterozygous family members displayed a nearly 60% reduction in SOD1 mRNA levels when compared with a wild-type control (Figure 2(A,B)). Furthermore, Western blot analyses confirmed the lack of SOD1 protein production in the patient (Figure 3(A)). As expected, the erythrocyte SOD enzymatic activity was nearly abolished (Figure 3(B)). The heterozygous family members displayed significantly reduced SOD1 protein expression, as well as enzymatic activity (by about 40%) when compared with the wild-type control (Figure 3(A,B)). Given these findings, ascorbic acid was initiated for its antioxidant effect.
Ascorbic acid-2 glucoside mitigates intestinal damage during pelvic radiotherapy in a rat bladder tumor model
Published in International Journal of Radiation Biology, 2022
Yasutoshi Ito, Tetsuo Yamamoto, Kosuke Miyai, Junya Take, Harry Scherthan, Anna Rommel, Stefan Eder, Konrad Steinestel, Alexis Rump, Matthias Port, Nariyoshi Shinomiya, Manabu Kinoshita
As ascorbic acid is water-soluble, it is easily and safely excreted into the urine after excessive intake and shows a low systemic toxicity, even at high doses. However, ascorbic acid is relatively unstable and easily oxidized in water leading to a rapid loss of antioxidant properties and chemical degradation. The ascorbic acid 2-glucoside (AA2G) is a conjugate consisting of one molecule of glucose linked at the C2-hydroxyl group of ascorbic acid, with the ascorbic acid in AA2G being stabilized by glucose (Chandrasekharan et al. 2009; Nakamura and Oku 2009). When the AA2G is administered orally to individuals, it is rapidly hydrolyzed into ascorbic acid and glucose by α-glucosidase that abundantly exists in the cell membranes of the GI epithelia (Chandrasekharan et al. 2009; Nakamura and Oku 2009). Thus, AA2G is a pro-drug preserving the stability of ascorbic acid and releasing the same antioxidative activity as ascorbic acid in the body.
Protective effects of ascorbic acid and calcitriol combination on airway remodelling in ovalbumin-induced chronic asthma
Published in Pharmaceutical Biology, 2020
Farzaneh Kianian, Seyed Morteza Karimian, Mehri Kadkhodaee, Nasrin Takzaree, Behjat Seifi, Hamid Reza Sadeghipour
Ascorbic acid is a water-soluble vitamin that contributes to antioxidant activity by scavenging ROS and reactive nitrogen species resulting in the prevention of oxidative damage to important biological macromolecules such as DNA, lipids and proteins (Smirnoff 2018; Kianian et al. 2019a). In addition to antioxidative effects, ascorbic acid is also known to modulate immune responses (Carr and Maggini 2017). However, two independent studies have reported some side effects associated with ascorbic acid in other organs including nausea, diarrhea and nephropathy (Sestili 1983; Lin et al. 2019). According to beneficial properties of ascorbic acid, it might be a good candidate to prevent airway remodelling during asthma. In this study, administration of ascorbic acid in effective dose significantly decreased levels of IL-13 and IgE compared to the asthma group. Similar to our results, a couple of studies have shown that administration of ascorbic acid modulates T cell proliferation and cytokine secretion and reduces IgE (Noh et al. 2005; Maeng et al. 2009). Moreover, in the current study, ascorbic acid administration in effective dose was able to decrease goblet cell hyperplasia and subepithelial fibrosis. The protective effects of ascorbic acid have been summarized in Figure 8.