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1.
medRxiv ; 2023 Dec 25.
Article in English | MEDLINE | ID: mdl-37961224

ABSTRACT

Intravenous (IV) vitamin C improves organ function and reduces inflammation in sepsis, an inflammatory state like the post-hematopoietic stem cell transplant (SCT) milieu. The safety and efficacy of parenteral vitamin C after allogeneic hematopoietic stem cell transplant (HSCT) were evaluated in a phase I/II trial and clinical outcomes compared with a propensity score - matched historical control. Methods: Patients with advanced hematologic malignancies were enrolled in a phase 2 clinical trial, receiving IV vitamin C, 50mg/kg/d, divided into 3 doses given on days 1-14 after HSCT, followed by 500 mg bid oral from day 15 until 6 months post-SCT. Results: 55 patients received IV vitamin C: these include 10/10 HLA-MRD and MUD (n=48) and 9/10 HLA MUD recipients (n=7). All patients enrolled were deficient in vitamin C at day 0 and had restoration to normal levels for the remainder of the course. Vitamin C recipients had lower non-relapse mortality (11% vs. 25%, p-value = 0.07) and consequently, improved survival compared to historical controls (82% vs 62% p=0.06), with no attributable grade 3 and 4 toxicities to vitamin C. Patients with myeloid malignancies had improved survival (83% vs. 54%, p=0.02) and non-relapse mortality (NRM) (10% vs. 37%, p=0.009), as well as chronic GVHD, with similar relapse rates compared to controls. Conclusions: In patients undergoing allogeneic HSCT the administration of IV vitamin C is safe and reduces non-relapse mortality improving overall survival. Randomized trials are needed to confirm the utility of this easily available and inexpensive therapy.

2.
Res Sq ; 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37986783

ABSTRACT

Intravenous (IV) vitamin C improves organ function and reduces inflammation in sepsis, an inflammatory state like the post-hematopoietic stem cell transplant (HCT) milieu. The safety and efficacy of parenteral vitamin C after allogeneic HCT were evaluated in a phase I/II trial. Clinical outcomes were compared with a propensity score - matched historical control. Methods: Patients with advanced hematologic malignancies received IV vitamin C, 50mg/kg/d, divided into 3 doses given on days 1-14 after HCT, followed by 500 mg bid oral from day 15 until 6 months post-SCT. Results: 55 patients received IV vitamin C. All patients were deficient in vitamin C at day 0. Vitamin C recipients had lower non-relapse mortality (NRM) (p = 0.07) and improved survival compared to historical controls (p=0.06), with no attributable grade 3 and 4 toxicities. Vitamin C recipients had similar relapse rate and acute graft versus host disease (GVHD) (p=0.35), but lower severe chronic GVHD (p=0.35). Patients with myeloid malignancies had improved survival (p=0.02) and NRM (p=0.009), as well as chronic GVHD, with similar relapse rates compared to controls. Conclusions: In patients undergoing allogeneic HCT the administration of IV vitamin C is safe and reduces non-relapse mortality and chronic GVHD improving overall survival.

3.
J Trauma Acute Care Surg ; 85(1S Suppl 2): S57-S67, 2018 07.
Article in English | MEDLINE | ID: mdl-29538225

ABSTRACT

BACKGROUND: Coagulopathy and inflammation induced by hemorrhagic shock and traumatic injury are associated with increased mortality and morbidity. Vitamin C (VitC) is an antioxidant with potential protective effects on the proinflammatory and procoagulant pathways. We hypothesized that high-dose VitC administered as a supplement to fluid resuscitation would attenuate inflammation, coagulation dysfunction, and end-organ tissue damage in a swine model of multiple injuries and hemorrhage. METHODS: Male Sinclair swine (n = 24; mean body weight, 27 kg) were anesthetized, intubated, mechanically ventilated, and instrumented for physiologic monitoring. Following stabilization, swine were subjected to shock/traumatic injury (hypothermia, liver ischemia and reperfusion, comminuted femur fracture, hemorrhagic hypotension), resuscitated with 500 mL of hydroxyethyl starch, and randomized to receive either intravenous normal saline (NS), low-dose VitC (50 mg/kg; LO), or high-dose VitC (200 mg/kg; HI). Hemodynamics, blood chemistry, hematology, and coagulation function (ROTEM) were monitored to 4 hours postresuscitation. Histological and molecular analyses were obtained for liver, kidney, and lung. RESULTS: Compared with VitC animals, NS swine showed significant histological end-organ damage, elevated acute lung injury scores, and increased mRNA expression of tissue proinflammatory mediators (IL-1ß, IL-8, TNFα), plasminogen activation inhibitor-1 and tissue factor. There were no statistically significant differences between treatment groups on mean arterial pressure or univariate measures of coagulation function; however, NS showed impaired multivariate clotting function at 4 hours. CONCLUSION: Although correction of coagulation dysfunction was modest, intravenous high-dose VitC may mitigate the proinflammatory/procoagulant response that contributes to multiple organ failure following acute severe multiple injuries. LEVEL OF EVIDENCE: Prospective randomized controlled blinded trial study, Preclinical (animal-based).


Subject(s)
Ascorbic Acid , Blood Coagulation Disorders , Inflammation , Multiple Trauma , Animals , Male , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/therapeutic use , Anticoagulants/administration & dosage , Anticoagulants/therapeutic use , Ascorbic Acid/administration & dosage , Ascorbic Acid/therapeutic use , Blood Coagulation Disorders/drug therapy , Blood Coagulation Disorders/etiology , Disease Models, Animal , Inflammation/drug therapy , Inflammation/etiology , Multiple Trauma/complications , Multiple Trauma/therapy , Random Allocation , Resuscitation/methods , Shock, Hemorrhagic/etiology , Shock, Hemorrhagic/therapy , Swine
4.
Antioxidants (Basel) ; 6(3)2017 Jul 12.
Article in English | MEDLINE | ID: mdl-28704937

ABSTRACT

Stored red blood cells (RBCs) undergo oxidative stress that induces deleterious metabolic, structural, biochemical, and molecular changes collectively referred to as "storage lesions". We hypothesized that vitamin C (VitC, reduced or oxidized) would reduce red cell storage lesions, thus prolonging their storage duration. Whole-blood-derived, leuko-reduced, SAGM (saline-adenine-glucose-mannitol)-preserved RBC concentrates were equally divided into four pediatric storage bags and the following additions made: (1) saline (saline); (2) 0.3 mmol/L reduced VitC (Lo VitC); (3) 3 mmol/L reduced VitC (Hi VitC); or (4) 0.3 mmol/L oxidized VitC (dehydroascorbic acid, DHA) as final concentrations. Biochemical and rheological parameters were serially assessed at baseline (prior to supplementation) and Days 7, 21, 42, and 56 for RBC VitC concentration, pH, osmotic fragility by mechanical fragility index, and percent hemolysis, LDH release, glutathione depletion, RBC membrane integrity by scanning electron microscopy, and Western blot for ß-spectrin. VitC exposure (reduced and oxidized) significantly increased RBC antioxidant status with varying dynamics and produced trends in reduction in osmotic fragility and increases in membrane integrity. CONCLUSION: VitC partially protects RBC from oxidative changes during storage. Combining VitC with other antioxidants has the potential to improve long-term storage of RBC.

5.
World J Crit Care Med ; 6(1): 37-47, 2017 Feb 04.
Article in English | MEDLINE | ID: mdl-28224106

ABSTRACT

AIM: To examine the effect of high doses of vitamin C (VitC) on ex vivo human platelets (PLTs). METHODS: Platelet concentrates collected for therapeutic or prophylactic transfusions were exposed to: (1) normal saline (control); (2) 0.3 mmol/L VitC (Lo VitC); or (3) 3 mmol/L VitC (Hi VitC, final concentrations) and stored appropriately. The VitC additive was preservative-free buffered ascorbic acid in water, pH 5.5 to 7.0, adjusted with sodium bicarbonate and sodium hydroxide. The doses of VitC used here correspond to plasma VitC levels reported in recently completed clinical trials. Prior to supplementation, a baseline sample was collected for analysis. PLTs were sampled again on days 2, 5 and 8 and assayed for changes in PLT function by: Thromboelastography (TEG), for changes in viscoelastic properties; aggregometry, for PLT aggregation and adenosine triphosphate (ATP) secretion in response to collagen or adenosine diphosphate (ADP); and flow cytometry, for changes in expression of CD-31, CD41a, CD62p and CD63. In addition, PLT intracellular VitC content was measured using a fluorimetric assay for ascorbic acid and PLT poor plasma was used for plasma coagulation tests [prothrombin time (PT), partial thrombplastin time (PTT), functional fibrinogen] and Lipidomics analysis (UPLC ESI-MS/MS). RESULTS: VitC supplementation significantly increased PLTs intracellular ascorbic acid levels from 1.2 mmol/L at baseline to 3.2 mmol/L (Lo VitC) and 15.7 mmol/L (Hi VitC, P < 0.05). VitC supplementation did not significantly change PT and PTT values, or functional fibrinogen levels over the 8 d exposure period (P > 0.05). PLT function assayed by TEG, aggregometry and flow cytometry was not significantly altered by Lo or Hi VitC for up to 5 d. However, PLTs exposed to 3 mmol/L VitC for 8 d demonstrated significantly increased R and K times by TEG and a decrease in the α-angle (P < 0.05). There was also a fall of 20 mm in maximum amplitude associated with the Hi VitC compared to both baseline and day 8 saline controls. Platelet aggregation studies, showed uniform declines in collagen and ADP-induced platelet aggregations over the 8-d study period in all three groups (P > 0.05). Collagen and ADP-induced ATP secretion was also not different between the three groups (P > 0.05). Finally, VitC at the higher dose (3 mmol/L) also induced the release of several eicosanoids including thromboxane B2 and prostaglandin E2, as well as products of arachidonic acid metabolism via the lipoxygenases pathway such as 11-/12-/15-hydroxyicosatetraenoic acid (P < 0.05). CONCLUSION: Alterations in PLT function by exposure to 3 mmol/L VitC for 8 d suggest that caution should be exerted with prolonged use of intravenous high dose VitC.

6.
World J Crit Care Med ; 6(1): 85-90, 2017 Feb 04.
Article in English | MEDLINE | ID: mdl-28224112

ABSTRACT

We report a case of virus-induced acute respiratory distress syndrome (ARDS) treated with parenteral vitamin C in a patient testing positive for enterovirus/rhinovirus on viral screening. This report outlines the first use of high dose intravenous vitamin C as an interventional therapy for ARDS, resulting from enterovirus/rhinovirus respiratory infection. From very significant preclinical research performed at Virginia Commonwealth University with vitamin C and with the very positive results of a previously performed phase I safety trial infusing high dose vitamin C intravenously into patients with severe sepsis, we reasoned that infusing identical dosing to a patient with ARDS from viral infection would be therapeutic. We report here the case of a 20-year-old, previously healthy, female who contracted respiratory enterovirus/rhinovirus infection that led to acute lung injury and rapidly to ARDS. She contracted the infection in central Italy while on an 8-d spring break from college. During a return flight to the United States, she developed increasing dyspnea and hypoxemia that rapidly developed into acute lung injury that led to ARDS. When support with mechanical ventilation failed, extracorporeal membrane oxygenation (ECMO) was initiated. Twelve hours following ECMO initiation, high dose intravenous vitamin C was begun. The patient's recovery was rapid. ECMO and mechanical ventilation were discontinued by day-7 and the patient recovered with no long-term ARDS sequelae. Infusing high dose intravenous vitamin C into this patient with virus-induced ARDS was associated with rapid resolution of lung injury with no evidence of post-ARDS fibroproliferative sequelae. Intravenous vitamin C as a treatment for ARDS may open a new era of therapy for ARDS from many causes.

7.
Int Wound J ; 13(4): 572-84, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26290474

ABSTRACT

Vitamin C (VitC) or ascorbic acid (AscA), a cofactor for collagen synthesis and a primary antioxidant, is rapidly consumed post-wounding. Parenteral VitC administration suppresses pro-inflammatory responses while promoting anti-inflammatory and pro-resolution effects in human/murine sepsis. We hypothesised that VitC could promote wound healing by altering the inflammatory, proliferative and remodelling phases of wound healing. Mice unable to synthesise VitC (Gulo(-/-) ) were used in this study. VitC was provided in the water (sufficient), withheld from another group (deficient) and supplemented by daily intra-peritoneal infusion (200 mg/kg, deficient + AscA) in a third group. Full thickness excisional wounds (6 mm) were created and tissue collected on days 7 and 14 for histology, quantitative polymerase chain reaction (qPCR) and Western blotting. Human neonatal dermal fibroblasts (HnDFs) were used to assess effects of In conclusion, VitC favorably on proliferation. Histological analysis showed improved wound matrix deposition and organisation in sufficient and deficient +AscA mice. Wounds from VitC sufficient and deficient + AscA mice had reduced expression of pro-inflammatory mediators and higher expression of wound healing mediators. Supplementation of HnDF with AscA induced the expression of self-renewal genes and promoted fibroblast proliferation. VitC favourably impacts the spatiotemporal expression of transcripts associated with early resolution of inflammation and tissue remodelling.


Subject(s)
Wound Healing , Animals , Antioxidants , Ascorbic Acid , Fibroblasts , Humans , Inflammation , Mice
8.
Crit Care ; 19: 418, 2015 Nov 27.
Article in English | MEDLINE | ID: mdl-26612352

ABSTRACT

Severe systemic inflammatory response to infection results in severe sepsis and septic shock, which are the leading causes of death in critically ill patients. Septic shock is characterised by refractory hypotension and is typically managed by fluid resuscitation and administration of catecholamine vasopressors such as norepinephrine. Vasopressin can also be administered to raise mean arterial pressure or decrease the norepinephrine dose. Endogenous norepinephrine and vasopressin are synthesised by the copper-containing enzymes dopamine ß-hydroxylase and peptidylglycine α-amidating monooxygenase, respectively. Both of these enzymes require ascorbate as a cofactor for optimal activity. Patients with severe sepsis present with hypovitaminosis C, and pre-clinical and clinical studies have indicated that administration of high-dose ascorbate decreases the levels of pro-inflammatory biomarkers, attenuates organ dysfunction and improves haemodynamic parameters. It is conceivable that administration of ascorbate to septic patients with hypovitaminosis C could improve endogenous vasopressor synthesis and thus ameliorate the requirement for exogenously administered vasopressors. Ascorbate-dependent vasopressor synthesis represents a currently underexplored biochemical mechanism by which ascorbate could act as an adjuvant therapy for severe sepsis and septic shock.


Subject(s)
Arginine Vasopressin/therapeutic use , Ascorbic Acid/therapeutic use , Norepinephrine/biosynthesis , Sepsis/drug therapy , Shock, Septic/drug therapy , Vasopressins/biosynthesis , Ascorbic Acid/administration & dosage , Hemodynamics , Humans , Norepinephrine/therapeutic use , Vasoconstrictor Agents/therapeutic use , Vasopressins/therapeutic use
9.
J Food Prot ; 77(12): 2181-8, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25474070

ABSTRACT

We propose a methodological framework for managing mycotoxin risks in the food processing industry. Mycotoxin contamination is a well-known threat to public health that has economic significance for the food processing industry; it is imperative to address mycotoxin risks holistically, at all points in the procurement, processing, and distribution pipeline, by tracking the relevant data, adopting best practices, and providing suitable adaptive controls. The proposed framework includes (i) an information and data repository, (ii) a collaborative infrastructure with analysis and simulation tools, (iii) standardized testing and acceptance sampling procedures, and (iv) processes that link the risk assessments and testing results to the sourcing, production, and product release steps. The implementation of suitable acceptance sampling protocols for mycotoxin testing is considered in some detail.


Subject(s)
Food Contamination/analysis , Food Contamination/prevention & control , Mycotoxins/analysis , Food Industry , Food Microbiology , Public Health , Risk Assessment
10.
Mediators Inflamm ; 2014: 173403, 2014.
Article in English | MEDLINE | ID: mdl-25294953

ABSTRACT

INTRODUCTION: Macrophage reprogramming is vital for resolution of acute inflammation. Parenteral vitamin C (VitC) attenuates proinflammatory states in murine and human sepsis. However information about the mechanism by which VitC regulates resolution of inflammation is limited. METHODS: To examine whether physiological levels of VitC modulate resolution of inflammation, we used transgenic mice lacking L-gulono-γ-lactone oxidase. VitC sufficient/deficient mice were subjected to a thioglycollate-elicited peritonitis model of sterile inflammation. Some VitC deficient mice received daily parenteral VitC (200 mg/kg) for 3 or 5 days following thioglycollate infusion. Peritoneal macrophages harvested on day 3 or day 5 were examined for intracellular VitC levels, pro- and anti-inflammatory protein and lipid mediators, mitochondrial function, and response to lipopolysaccharide (LPS). The THP-1 cell line was used to determine the modulatory activities of VitC in activated human macrophages. RESULTS: VitC deficiency significantly delayed resolution of inflammation and generated an exaggerated proinflammatory response to in vitro LPS stimulation. VitC sufficiency and in vivo VitC supplementation restored macrophage phenotype and function in VitC deficient mice. VitC loading of THP-1 macrophages attenuated LPS-induced proinflammatory responses. CONCLUSION: VitC sufficiency favorably modulates macrophage function. In vivo or in vitro VitC supplementation restores macrophage phenotype and function leading to timely resolution of inflammation.


Subject(s)
Ascorbic Acid/metabolism , Ascorbic Acid/therapeutic use , Inflammation/drug therapy , Animals , Blotting, Western , Cell Line , Humans , Inflammation/chemically induced , Inflammation/metabolism , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/metabolism , Mice , Mice, Knockout , Mice, Transgenic , Microscopy, Fluorescence , Peritonitis/chemically induced , Peritonitis/drug therapy , Peritonitis/metabolism , Real-Time Polymerase Chain Reaction , Thioglycolates/toxicity
11.
Am J Physiol Lung Cell Mol Physiol ; 303(1): L20-32, 2012 Jul 01.
Article in English | MEDLINE | ID: mdl-22523283

ABSTRACT

Bacterial infections of the lungs and abdomen are among the most common causes of sepsis. Abdominal peritonitis often results in acute lung injury (ALI). Recent reports demonstrate a potential benefit of parenteral vitamin C [ascorbic acid (AscA)] in the pathogenesis of sepsis. Therefore we examined the mechanisms of vitamin C supplementation in the setting of abdominal peritonitis-mediated ALI. We hypothesized that vitamin C supplementation would protect lungs by restoring alveolar epithelial barrier integrity and preventing sepsis-associated coagulopathy. Male C57BL/6 mice were intraperitoneally injected with a fecal stem solution to induce abdominal peritonitis (FIP) 30 min prior to receiving either AscA (200 mg/kg) or dehydroascorbic acid (200 mg/kg). Variables examined included survival, extent of ALI, pulmonary inflammatory markers (myeloperoxidase, chemokines), bronchoalveolar epithelial permeability, alveolar fluid clearance, epithelial ion channel, and pump expression (aquaporin 5, cystic fibrosis transmembrane conductance regulator, epithelial sodium channel, and Na(+)-K(+)-ATPase), tight junction protein expression (claudins, occludins, zona occludens), cytoskeletal rearrangements (F-actin polymerization), and coagulation parameters (thromboelastography, pro- and anticoagulants, fibrinolysis mediators) of septic blood. FIP-mediated ALI was characterized by compromised lung epithelial permeability, reduced alveolar fluid clearance, pulmonary inflammation and neutrophil sequestration, coagulation abnormalities, and increased mortality. Parenteral vitamin C infusion protected mice from the deleterious consequences of sepsis by multiple mechanisms, including attenuation of the proinflammatory response, enhancement of epithelial barrier function, increasing alveolar fluid clearance, and prevention of sepsis-associated coagulation abnormalities. Parenteral vitamin C may potentially have a role in the management of sepsis and ALI associated with sepsis.


Subject(s)
Acute Lung Injury/drug therapy , Ascorbic Acid/pharmacology , Sepsis/drug therapy , Abdomen/microbiology , Abdomen/pathology , Acute Lung Injury/metabolism , Acute Lung Injury/microbiology , Acute Lung Injury/physiopathology , Animals , Biomarkers/blood , Blood Coagulation/drug effects , Bronchoalveolar Lavage/methods , Cell Line , Cytoskeletal Proteins/metabolism , Humans , Inflammation/blood , Inflammation/metabolism , Inflammation/physiopathology , Ion Channels/metabolism , Ion Transport/drug effects , Lung/drug effects , Lung/metabolism , Lung/physiopathology , Male , Mice , Mice, Inbred C57BL , Neutrophils/drug effects , Neutrophils/metabolism , Neutrophils/physiology , Peritonitis/drug therapy , Peritonitis/metabolism , Peritonitis/microbiology , Peritonitis/physiopathology , Permeability/drug effects , Pulmonary Alveoli/drug effects , Pulmonary Alveoli/metabolism , Pulmonary Alveoli/physiopathology , Respiratory Mucosa/drug effects , Respiratory Mucosa/metabolism , Respiratory Mucosa/physiopathology , Sepsis/blood , Sepsis/metabolism , Sepsis/physiopathology , Sodium-Potassium-Exchanging ATPase/metabolism
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