Ascorbic Acid Treatment Research Articles

Investigating Drug Interactions And Antibacterial Activity Of Vitamin C On Pathogenic Factors Of Escherichia Coli Clinical Isolates

Today, the phenomenon of multi-drug resistance has become a major cause of concern, and insufficient achievements have been made in the development of new antibiotics for the treatment of bacterial infections. Therefore, there is an unmet need for new auxiliary search. Vitamin C is one such promising supplement. The current study was conducted with the aim of explaining the antibacterial interaction effect of vitamin C in different concentrations (5-20 mg/ml) and drugs effective on Escherichia coli bacteria. In order to collect clinical samples during the months of September to November 2022, clinical samples were collected from 100 patients suspected of urinary tract infection who referred to medical centers. For identification, biochemical tests and gram staining and culture in IMViC and EMB environments were used to see metallic green polish. Then antimicrobial sensitivity test And the effect of antibiotic on biofilm formation, the effect of antibiotic and ascorbic acid on biofilm formation, biofilm inhibition rate was done for the single and combined effects of both antimicrobial substances. Finally, in order to investigate and identify the virulence gene of the isolated strains, DNA extraction was performed by PCR method. 45 samples of urinary infection culture were identified from the total of 100 samples collected, in 45 (45%) of them colonies with metallic polish were observed. 45% were men and 55% were women, and of these, a total of 45 positive E. coli cases were found in women and 17 positive cases were seen in men. Less than one year, teenagers, young and old were divided. 2 cases (2%) were in the age group of less than one year, 3 cases (3%) were teenagers, 63 cases (63%) were young and 32 cases (32%) were in the age group of middle-aged people. In a situation where the ability to form biofilm under vitamin C (ascorbic acid) treatment was not very effective and did not differ much from normal conditions, antibiotic treatment (under MBC gentamicin treatment) was somewhat successful in inhibiting biofilm formation, finally with the combination of antibiotic and Ascorbic acid was completely isolated in many resistant strains, the inability to form biofilm was evident, and this indicated the synergistic effects in the investigated composition. As the results showed, the ability to produce biofilm in the samples that had the target genes in this study was not much different from the other samples. Considering the increasing resistance to some antibiotics and wide changes in the effective spectrum of drugs and preventing the increase of drug-resistant cases, the necessity of conducting drug sensitivity tests seems very necessary. The high prevalence of E. coli antibiotic resistance and the high percentage of resistance genes in patients suffering from infections caused by this bacterium can indicate the excessive use of antibiotics. Finally, the prevalence of antibiotic resistance is a useful marker for investigating resistance genes and can be useful in ecological investigations. Also, with clear inhibitory effects, the selected antibiotic in this study along with ascorbic acid, this vitamin can be used as a supplement in some infections caused by E. coli bacteria.

Exploring transient global transcriptional changes induced by ascorbic acid revealed via atKAS-seq profiling.

Transcription initiates the formation of single-stranded DNA (ssDNA) regions within the genome, delineating transcription bubbles, a highly dynamic genomic process. Kethoxal-assisted single-stranded DNA sequencing (KAS-seq) utilizing N3-kethoxal has emerged as a potent tool for mapping specific guanine positions in ssDNA on a genome-wide scale. However, the original KAS-seq method required the costly Accel-NGS Methyl-seq DNA library kit. This study introduces an optimized iteration of the KAS-seq technique, referred to as adapter-tagged KAS-seq (atKAS-seq), incorporating an adapter tagging strategy. This modification involves integrating sequencing adapters via complementary strand synthesis using random N9 tagging. Additionally, by harnessing the potential of ascorbic acid (ASC), recognized for inducing global epigenetic changes, we employed the atKAS-seq methodology to elucidate critical pathways influenced by short-term, high-dose ASC treatment. Our findings underscore that atKAS-seq enables rapid and precise analyses of transcription dynamics and enhancer activities concurrently. This method offers a streamlined, cost-efficient, and low-input approach, affirming its utility in probing intricate genomic regulatory mechanisms.

Ascorbic acid predominantly kills cancer stem cell-like cells in the hepatocellular carcinoma cell line Li-7 and is more effective at low cell density and in small spheroids

The development of therapies that target cancer stem cells (CSCs) is an important challenge in cancer research. The antioxidant system is enhanced in CSCs, which may lead to resistance to existing therapies. Ascorbic acid (AA) has the potential to act as both an antioxidant and a pro-oxidant agent, but its effects on CSCs are a subject of current research. Here, we investigated the effect of AA focusing specifically on CSCs with the hepatocellular carcinoma cell line Li-7. The Li-7 cell line is heterogenous consisting of CD166- and CD166+ cells; CD166- cells include CSC-like cells (CD13+CD166- cells) and CD13−CD166- cells that can revert to CD13+CD166- cells. The addition of AA to the culture medium caused cell death in both cell populations in CD166- cells in a concentration dependent manner. In contrast, AA administration had a limited effect on CD166+ non-CSC cells. The level of reactive oxygen species after AA treatment was elevated only in CD166- cells. The effect of AA only occurred at low cell densities in 2D and 3D cultures. In a mouse tumor model injected with Li-7 cells, intraperitoneal administration of AA failed to prevent tumor formation but appeared to delay tumor growth. Our findings shed light on why AA administration has not become a mainstream treatment for cancer treatment; however, they also show the possibility that AA can be used in therapies to suppress CSCs.

Salmonella control for dried apple cubes

Pathogen contamination in low-moisture foods prepared by drying is a food safety concern. Two thermal treatments were explored in this research as pathogen control measures for apple drying operations: high humidity air heating (HHAH) and ascorbic acid (AA) treatments. Their effectivenesses on Salmonella inactivation were assessed. Apple cubes (6.4 mm) inoculated with a three-strain Salmonella cocktail (S. Enteritidis PT 30, S. Montevideo, and S. Agona 447967) were subjected to HHAH and AA treatments, and then enumerated for the survival of Salmonella. In parallel, uninoculated apple cubes treated with HHAH or AA were dried by hot air at 90 °C for 70 min. The moisture content and color values of the dried apple cubes were measured. The results revealed that HHAH treatment at 70 °C for 16 min, at 90 °C for 9 min, and AA treatment using 3.4% ascorbic solutions at 65 °C for 90 s achieved 6.9 ± 0.4, 6.2 ± 0.2, and 7.9 ± 0.6 log CFU/g reduction, respectively. The moisture content of dried apple cubes was not significantly different, highlighting the potential of these methods for enhancing microbial safety of dried apples. The HHAH treatment resulted in an increased browning effect on dried apple cubes, while the AA treatment reduced the browning of dried apple cubes. This study offers valuable insight into preventive controls for pathogen management in food drying operations.

The effect of nano/microparticles of bee pollen on the shelf life of high-fat cooked sausage during refrigerated storage.

Sausage is susceptible to oxidative changes in lipids and microbial spoilage due to the presence of water, fat, protein, and vitamins. Bee pollen (BP) as a source of potential antioxidants and antibacterial compounds can effectively prevent lipid peroxidation and microbial spoilage in meat products. The aim of the present study was to investigate the antibacterial and antioxidant activities of BP and the effects of nano/microparticles of bee pollen extract (n/m BP) at a concentration of 125 and 250 mg/100 g meat on the oxidative stability and microbial growth of high-fat sausage during 30 days of storage at 4°C. The formation of BP particles in the nano/micro range was confirmed by scanning electron microscopy. High concentrations of total phenolic compounds (28.26 ± 0.10 mg GAE/g BP) with antioxidant activity (EC50 = 5.4 ± 0.07 mg/mL) were detected in BP. Based on the microdilution assay, the minimum inhibitory concentration of n/m BP for all test bacteria was 1000 (μg/mL) and the minimum bactericidal concentration of n/m BP was 2000 (μg/mL) for Staphylococcus aureus and Bacillus cereus and 4000 (μg/mL) for Escherichia coli and Pseudomonas aeruginosa. The n/m BP treatment (250 mg/100 g meat) showed a higher pH value (p < .05) and lower TBARS values (p < .05) than the ascorbic acid treatment (100 mg/100 g meat) and the control during the storage period. The microbial analysis showed that the addition of n/m BP led to a significant decrease (p < .05) in the total bacterial count, coliforms, S. aureus, and fungal population compared to the other samples. The results show that the addition of n/m BP (125 mg/100 g) can improve the texture, taste, and overall acceptability of the sausage compared to the control sample. In conclusion, this study suggests that BP can replace synthetic antioxidants in high-fat sausages at the nano/microparticle level.

Deducing solute differential heat capacity from experimental solubilities. An exemplified treatment of ascorbic acid to improve solubility prediction

ContextSolubility prediction based on the general solubility equation (GSE) rests on reliable values for the isobaric heat capacity difference ΔCp,1 of the solid solute. Usually, this value is estimated with either zero or the melting entropy ΔS1(Tm,1) or, in few cases, is extrapolated from data of thermally stable melts of the solute. This causes uncertainties in the prediction. ObjectiveTo improve prediction accuracy a simple regression method is proposed that determines ΔCp,1 from measured solubilities. Materials and methodsPublished experimental solubilities in neat organic solvents at 298 K of a model compound (L-(+)-ascorbic acid (LAA)) have been regressed using the GSE together with the Hansen parameter model for the activity coefficient. Results and discussionRegression yielded ΔCp,1 = 238 J∙mol−1∙K−1 which agrees well with cross-validation results and is consistent with estimates from various group contribution methods. It was found that prediction accuracy improved in the order of increasing ΔCp,1, that is, from 0, via 91 (=ΔS1(Tm,1)) to 238 J∙mol−1∙K−1. It could be shown that mole fraction solubility of LAA can be forecast this way with an accuracy within current inter-laboratory variation. ConclusionThe proposed method shows a general way to improve prediction accuracy of activity coefficient based solubility models by determining ΔCp,1 without resorting to common assumptions. The method is universally applicable and easy to implement.

Successful Treatment, with Chemotherapy and Intravenous Administration of Ascorbic Acid, of a Patient with Peripheral T-Cell Lymphoma, Not Otherwise Specified

Here, we report the case of a 64-year-old man with peripheral T-cell lymphoma, not otherwise specified, who complained of diffuse lymphadenopathy and pancytopenia. This patient received the CHOP regimen followed by the CHP plus brentuximab vedotin regimen, and eventually experienced severe adverse effects, such as leukocytopenia and thrombocytopenia. He was then intravenously administered high doses of ascorbic acid to enhance the effects of chemotherapy drugs and reduce the intensity of the side effects. Positron emission tomography-computed tomography revealed a complete response of the lesions to combination therapy. This case report demonstrated the feasibility, efficacy, and acceptable toxicity of high-dose ascorbic acid in patients undergoing chemotherapy.

Ascorbic acid induces ferroptosis via STAT3/GPX4 signaling in oropharyngeal cancer

Ferroptosis is recognized as a new type of regulated cell death initiated by iron-dependent accumulation of lipid peroxidation. Recent studies have shown that the administration of ascorbic acid (AA) preferentially kills tumor cells by impairing iron metabolism and exerting pro-oxidant effects. Despite mounting evidence indicating the anticancer potential of AA, the underlying molecular mechanisms remain unknown. In this study, we demonstrated that AA decreased cell viability and Ki67 expression, along with its accumulation in the G0/G1 phase in FaDu and SCC-154 cell lines. Furthermore, AA exposure induced morphological changes in mitochondria associated with ferroptosis. AA-induced ferroptosis is accompanied by depletion of glutathione (GSH) and increased levels of ferrous ions (Fe2+), reactive oxygen species (ROS), and malondialdehyde (MDA). However, these ferroptotic effects were ameliorated by deferoxamine and N-acetylcysteine. Network pharmacology results showed that signal transducer and activator of transcription 3 (STAT3) is a key target of AA against oropharyngeal cancer. AA markedly downregulates the relative mRNA expression of STAT3 and glutathione peroxidase 4 (GPX4). Immunoblotting indicated that the protein levels of p-STAT3, STAT3, and GPX4 in FaDu and SCC-154 cells decreased significantly in response to AA treatment. Mechanistically, a chromatin immunoprecipitation assay confirmed that AA exposure reduced STAT3 expression in the GPX4 promoter region. Additionally, AA-induced inhibition of cell growth and ferroptosis was suppressed by STAT3 and GPX4 overexpression, respectively. In summary, AA inhibited oropharyngeal cancer cell growth in vitro by regulating STAT3/GPX4-mediated ferroptosis, which may provide a novel theoretical basis for the clinical treatment of oropharyngeal cancer with AA.

Ascorbic Acid Treatments as Effective and Safe Anti-Aging Therapies for Sensitive Skin.

The most common signs of aging skin include a decrease in firmness and density, uneven skin tone, and a tendency to erythema. There is an ever-increasing interest in aesthetic treatments that maintain the skin's favorable appearance. However, such therapies are difficult in the case of sensitive skin, defined as a set of stimuli-triggered symptoms (stinging, erythema, burning, and itching) that would not appear in healthy skin. Sensitive skin is common and affects, to varying degrees, about half of the European population. This study was aimed at evaluating the effects of ascorbic acid-a known antioxidant-applied with sonophoresis and microneedling on the signs of photoaging in reactive and erythematous skin. A significant improvement in skin elasticity was observed after a series of tests. A significant reduction in erythema was observed after both therapies. The greatest reduction was observed on the cheeks after applying vitamin C combined with microneedling. At the same time, the results showed an excellent tolerance of both treatments, which proved them to be safe and effective.

Effect of ascorbic acid treatment on physicochemical and emulsifying properties of highland barley protein

The current study investigated the impact of ascorbic acid (AA) on physicochemical and emulsifying properties of highland barley protein (HBP). Emulsifying and solubility of AA-modified HBP increased compared to its native state. However, excessive AA concentration induced protein reaggregation, leading to a deterioration of these properties. At a concentration of 0.3 % (w/v) AA, the highland barley protein emulsion (HBPE) exhibited the smallest average particle size (0.59 μm), and the protein demonstrated superior emulsification properties. The observed alterations stem from the formation of covalent bonds between HBP and AA through the Maillard reaction. These changes also relate to modifications in the secondary structure, marked by a notable increase of 60.25 % in β-turns, accompanied by reductions of 16.45 % in α-helices and 33.84 % in β-sheets. This was confirmed through analyses of disulfide bond content and FTIR. The outcomes of this study hold promise for enhancing the stability of emulsion formulations based on HBP, achieved by harnessing the complex formation between HBP and AA.

Genome-wide identification of MAPK family in papaya (Carica papaya) and their involvement in fruit postharvest ripening

BackgroundPapaya (Carica papaya) is an economically important fruit cultivated in the tropical and subtropical regions of China. However, the rapid softening rate after postharvest leads to a short shelf-life and considerable economic losses. Accordingly, understanding the mechanisms underlying fruit postharvest softening will be a reasonable way to maintain fruit quality and extend its shelf-life.ResultsMitogen-activated protein kinases (MAPKs) are conserved and play essential roles in response to biotic and abiotic stresses. However, the MAPK family remain poorly studied in papaya. Here, a total of nine putative CpMAPK members were identified within papaya genome, and a comprehensive genome-wide characterization of the CpMAPKs was performed, including evolutionary relationships, conserved domains, gene structures, chromosomal locations, cis-regulatory elements and expression profiles in response to phytohormone and antioxidant organic compound treatments during fruit postharvest ripening. Our findings showed that nearly all CpMAPKs harbored the conserved P-loop, C-loop and activation loop domains. Phylogenetic analysis showed that CpMAPK members could be categorized into four groups (A-D), with the members within the same groups displaying high similarity in protein domains and intron–exon organizations. Moreover, a number of cis-acting elements related to hormone signaling, circadian rhythm, or low-temperature stresses were identified in the promoters of CpMAPKs. Notably, gene expression profiles demonstrated that CpMAPKs exhibited various responses to 2-chloroethylphosphonic acid (ethephon), 1-methylcyclopropene (1-MCP) and the combined ascorbic acid (AsA) and chitosan (CTS) treatments during papaya postharvest ripening. Among them, both CpMAPK9 and CpMAPK20 displayed significant induction in papaya flesh by ethephon treatment, and were pronounced inhibition after AsA and CTS treatments at 16 d compared to those of natural ripening control, suggesting that they potentially involve in fruit postharvest ripening through ethylene signaling pathway or modulating cell wall metabolism.ConclusionThis study will provide some valuable insights into future functional characterization of CpMAPKs, and hold great potential for further understanding the molecular mechanisms underlying papaya fruit postharvest ripening.

Effect of Salinity and ascorbic acid treatments on growth, yield and antioxidant enzymes activity of barley plants

Effect of Salinity and ascorbic acid treatments on growth, yield and antioxidant enzymes activity of barley plants

Ascorbic acid and its transporter SVCT2, affect radial glia cells differentiation in postnatal stages.

Radial glia (RG) cells generate neurons and glial cells that make up the cerebral cortex. Both in rodents and humans, these stem cells remain for a specific time after birth, named late radial glia (lRG). The knowledge of lRG and molecules that may be involved in their differentiation is based on very limited data. We analyzed whether ascorbic acid (AA) and its transporter SVCT2, are involved in lRG cells differentiation. We demonstrated that lRG cells are highly present between the first and fourth postnatal days. Anatomical characterization of lRG cells, revealed that lRG cells maintained their bipolar morphology and stem-like character. When lRG cells were labeled with adenovirus-eGFP at 1 postnatal day, we detected that some cells display an obvious migratory neuronal phenotype, suggesting that lRG cells continue generating neurons postnatally. Moreover, we demonstrated that SVCT2 was apically polarized in lRG cells. In vitro studies using the transgenic mice SVCT2+/- and SVCT2tg (SVCT2-overexpressing mouse), showed that decreased SVCT2 levels led to accelerated differentiation into astrocytes, whereas both AA treatment and elevated SVCT2 expression maintain the lRG cells in an undifferentiated state. In vivo overexpression of SVCT2 in lRG cells generated cells with a rounded morphology that were migratory and positive for proliferation and neuronal markers. We also examined mediators that can be involved in AA/SVCT2-modulated signaling pathways, determining that GSK3-β through AKT, mTORC2, and PDK1 is active in brains with high levels of SVCT2/AA. Our data provide new insights into the role of AA and SVCT2 in late RG cells.

Effect of Ascorbic Acid and Polythylene Plastic Packaging on Browning and Shelf Life of Langsat Fruit (Lansium domesticum)

Langsat (Lansium domesticum) is a tropical fruit classified as a climacteric fruit that can only last 4-6 days after harvesting. Skin colour is easier to brown and black after 4 days of harvesting. This condition does not affect the fruit flesh, but visually, it becomes unappealing. Ascorbic acid and polyethylene plastic packaging could be applied to extend shelf life and slow browning. This study aims to investigate the effect of different concentrations of ascorbic acid treatment and polyethylene plastic (PE) packaging on the browning index and shelf life of lan and to determine the best concentration of ascorbic acid during storage at 15 °C. The treatments used in this study involved immersing langsat fruit in different ascorbic acid concentrations: 1.5%, 2%, and 2.5%, respectively. The langsat fruit was then packaged using polyethylene plastic and stored at 15 °C. The results showed that using ascorbic acid could delay browning by up to 14 days, with the lowest browning index found in langsat fruit immersed in 2.5% ascorbic acid concentration and packaged in polyethylene plastic. Polyethylene plastic packaging and ascorbic acid during storage affected the shelf life of langsat fruit, extending it to 14 days.

Effect of postharvest treatments and storage temperature on the physiological, nutritional, and shelf-life of broccoli (Brassica oleracea) microgreens

Microgreens are categorized in the class of ‘super foods’ due to their high content of phytochemical and bioactive compounds. Rapid senescence and short life span are the restrictive parameters for the industrial production and marketing of these immature greens. Hence, there is a need to improve the production and storage conditions of microgreens to magnify postharvest quality, life span, and safety of microgreens, thereby emerging markets. To prolong their shelf life, effect of different postharvest treatments (MAP (modified Atmospheric Packaging) and GRAS chemical treatments) and storage temperature on physiological, nutritional and shelf life of broccoli (Brassica oleracea) microgreens studied. The effect of ascorbic acid + citric acid (0.25 % w/v each) along with MAP conditions (15 % CO2 + 5 % O2 + balanced N2) stored at 5 °C was used for post-harvest quality evaluation of broccoli microgreens. Microgreens treated with an organic acid in high CO2 conditions retained significantly (p < 0.05) higher bioactive compounds in terms of total phenols (1247.68 mg GAE/100 g FW), flavonoids (56.9 mg QE/100 g FW), and chlorophyll (42.12 mg/100 g FW) with better antioxidant activity (44.78 % inhibition). In addition, MAP conditions in the package significantly (p < 0.05) suppressed the weight loss that helped to retain better firmness. The combined effect of organic acids and MAP conditions significantly (p < 0.05) reduced the microbial load with better color quality and higher overall acceptability. The results indicate that post-harvest treatment of ascorbic acid + citric acid along with MAP conditions could be the practical approach to enhance the shelf life of microgreens up to 12 days while maintaining the nutritional quality, to provide avenues for better marketability and commercial gains.

The Role of Apoptosis and Oxidative Stress in a Cell Spheroid Model of Calcific Aortic Valve Disease.

Calcific aortic valve disease (CAVD) is the most common heart valve disease among aging populations. There are two reported pathways of CAVD: osteogenic and dystrophic, the latter being more prevalent. Current two-dimensional (2D) in vitro CAVD models have shed light on the disease but lack three-dimensional (3D) cell-ECM interactions, and current 3D models require osteogenic media to induce calcification. The goal of this work is to develop a 3D dystrophic calcification model. We hypothesize that, as with 2D cell-based CAVD models, programmed cell death (apoptosis) is integral to calcification. We model the cell aggregation observed in CAVD by creating porcine valvular interstitial cell spheroids in agarose microwells. Upon culture in complete growth media (DMEM with serum), calcium nodules form in the spheroids within a few days. Inhibiting apoptosis with Z-VAD significantly reduced calcification, indicating that the calcification observed in this model is dystrophic rather than osteogenic. To determine the relative roles of oxidative stress and extracellular matrix (ECM) production in the induction of apoptosis and subsequent calcification, the media was supplemented with antioxidants with differing effects on ECM formation (ascorbic acid (AA), Trolox, or Methionine). All three antioxidants significantly reduced calcification as measured by Von Kossa staining, with the percentages of calcification per area of AA, Trolox, Methionine, and the non-antioxidant-treated control on day 7 equaling 0.17%, 2.5%, 6.0%, and 7.7%, respectively. As ZVAD and AA almost entirely inhibit calcification, apoptosis does not appear to be caused by a lack of diffusion of oxygen and metabolites within the small spheroids. Further, the observation that AA treatment reduces calcification significantly more than the other antioxidants indicates that the ECM stimulatory effect of AA plays a role inhibiting apoptosis and calcification in the spheroids. We conclude that, in this 3D in vitro model, both oxidative stress and ECM production play crucial roles in dystrophic calcification and may be viable therapeutic targets for preventing CAVD.

Genome wide and comprehensive analysis of the cytochrome P450 (CYPs) gene family in Pyrus bretschneideri: Expression patterns during Sporidiobolus pararoseus Y16 enhanced with ascorbic acid (VC) treatment

Cytochrome P450s (CYPs) constitute the largest group of enzymes in plants and are involved in a variety of processes related to growth and protection. However, the CYP gene superfamily in pear (Pyrus bretschneideri) and their characteristics is unclear. Through a comprehensive genome-wide analysis, this article identified a total of 74 CYP genes in the P. bretschneideri genome, which were categorized into fourteen families. Motif analysis reveals that most of the ten motifs predicted were with the p450 conserved domain. The majority of the CYP genes have exon arrangements. Furthermore, promoter analysis unveiled a multitude of cis-acting elements associated with diverse responsiveness including hormones, light responsive, anoxic specific inducibility and anaerobic induction. Analysis of the transcriptome data reveal that about 80% of the pear CYPs genes were upregulated and they were positively correlated with the antioxidant's parameters such as total flavonoids and total phenol content as well as ABTS and DPPH radicals. RT-qPCR analysis confirmed that the CYP genes could be regulated in pear. Collectively, our results reveal comprehensive insights into the CYP superfamily in pear and make a valuable contribution to the ongoing process of functional validation.

Phase II Study Assessing Safety and Preliminary Efficacy of High Dose Intravenous Ascorbic Acid in Patients with TET2 Mutant Clonal Cytopenias

Background: Clonal cytopenia(s) of undetermined significance ( CCUS) is defined as persistent cytopenias arising in the context of myeloid neoplasm ( MN)-associated somatic mutations ( MT) in hematopoietic stem cells. Patients ( PTs) with TET2MT CCUS have a high probability of progression to MN. To date, no FDA-approved therapies exist for CCUS, and PTs often have similar cytopenias/transfusion needs as those with myelodysplastic syndromes ( MDS). TET2 is an ascorbic acid (AA)-dependent dioxygenase that catalyzes the conversion of 5-methylcytosine ( 5mC) to 5-hydroxymethylcytosine ( 5hmC), providing rationale to study high-dose IV (HI)-AA in TET2MT CCUS. Here we report the final results of this pilot trial. Methods: This is an investigator-initiated, single-institutional, phase II trial assessing the safety and efficacy of HI-AA in PTs with TET2MT CCUS (NCT03418038). PTs≥ 18 years with ≥1 TET2MT with or without additional somatic MTs, without prior treatment, and with any of the following laboratory criteria: (1) hemoglobin ( Hb) ≤10g/dL, (2) absolute neutrophil count ( ANC) ≤1(10^9/L), (3) platelet count ( PLT)≤100 (10^9/L) were eligible. HI-AA (1g/kg, maximum 100g) was given 3 times weekly for 12 weeks. The primary endpoint was hematologic response rates determined by MDS IWG 2018 criteria at week 20. (Platzbecker Blood 2018) and reported as hematologic improvement ( HI)- erythropoietic ( HI-E), platelets ( HI-P), neutrophils ( HI-N). Secondary endpoints include safety and adverse events ( AEs), graded by NCI-CTCAE v4.03. Correlative studies include changes in TET2MT variant allele fraction ( VAF), in vitro colony formation and differentiation, global and sequence-specific DNA methylation/hydroxymethylation, and quantitative 5hmC estimated by IHC in bone marrow biopsy specimens. Results: Ten patients were enrolled, with a median age of 71.4 (range: 65, 79) years, 8 (80%) males. The median number of mutations was 3, with 9 (90%) having co-mutations. All PTs but one [-Y] had normal karyotype. Baseline Hb levels were normal in all but one who was red blood transfusion dependent. Five (50%) PTs were thrombocytopenic, and 5 (50%) PTs had ANC&amp;lt;1 (10^9/L). ( Table). HI-AA was well tolerated with the most common AEs being infusion-related polyuria (40%) and polydipsia (40%, 3 Grade 1, 1 Grade 2). One (10%) PT had constipation and headaches (both Grade 1), and 1 (10%) experienced dyspepsia. No treatment-related Grade 3 or 4 AEs' or deaths were reported. The median follow-up duration was 16.8 months (range: 9.4, 24.1). Overall, no PTs met the criteria for HI. There were no significant differences with regards to median Hb, PLT, and ANC values at baseline, week 20, and 1-year (median Hb: 13.3, 12.5, and 12.7 g/dL, p=0.93; PLT: 97 vs. 120 vs. 92.5X10^9/L, p&amp;gt;0.99, and ANC: 0.9 vs. 1.2 vs. 1.3X10^9/L, p=0.99). By CTCAE grading criteria for cytopenias, 3 (30%) PTs had an improvement in severity of cytopenias, while 2 had worsening. One (10%) PT had an improvement in PLT (baseline vs. week 20: 62 vs 192X10^9/L) but was morphologically deemed to meet criteria for CMML-1 at week 20. Four (40%) PTs met criteria for disease progression (PT_4, 7,8,10); CMML-1- 2 and MDS-2. The median time to progression was 5 months (95% CI: 4.9, unreached). Two PTs had mutational clonal evolution, with 1 (PT_8) acquiring a RUNX1 (VAF: 20%) and 1 (PT_9) acquiring 2 CBL mutations (both VAF:4%) at one-year follow-up. There were no significant differences regarding the clinical characteristics or the TET2 variants between PTs who had stable disease vs. progression. There were no significant differences in TET2 VAF at baseline, week 20, and 1-year (median: 39% vs. 43% vs. 42%, p=0.54). We profiled changes in 5-mC and 5-hmC (Ilumina EpicArray) in PTs pre- and post-IV AA treatment and did not observe global changes. However, we were able to highlight site-specific changes in differentially methylated regions, largely resulting in hypomethylation at enhancer sites and affecting actively transcribed states in PTs with an improvement in cytopenia(s) severity by CTACE criteria ( Figure). Conclusion: We report the final safety and efficacy analysis of HI-AA in PTs with TET2 MT CCUS. The trial data suggest that HI-AA is safe and well tolerated. Although there were no significant responses by IWG MDS criteria, alleviation in severity of cytopenias in a subset of PTs (n=3) along with correlative epigenetic changes in enhancer regions, needs further exploration.

Abstract 12850: Ascorbic Acid Promotes Ventricular Myosin Light Chain-2 Protein Expression and Maturation of Human Induced Pluripotent Stem Cells Derived Cardiomyocytes

Introduction: The potentially unlimited number of cardiomyocyte (CMs) derived from human induced pluripotent stem cells (hiPSCs) facilitates high throughput applications like cell transplantation, disease modelling, and cardiotoxicity testing during drug development. Despite promising progress in these areas, a major disadvantage that limits the use of hiPSC derived CMs (hiPSC-CMs) is their immaturity. Hypothesis: Ascorbic acid (AA) can promote ventricular myosin light chain-2 (MLC-2v) expression and maturation of hiPSC-CMs. Methods: Three hiPSC lines (PCBC-hiPSC, DP3-hiPSCs, and MLC2v-mEGFP-hiPSC) were differentiated into CMs (PCBC-CMs, DP3-CMs,a nd MLC2v-CMs, respectively) with or without retinoic acid (RA). hiPSC-CMs were either maintained up to day 30 of contraction (D30C), or D60C, or purified using lactate acid and used for experiments. Purified hiPSC-CMs were cultured in basal maturation medium (BMM) or BMM supplemented with AA for 14 days. The AA treated and non-treated hiPSC-CMs were characterized for sarcomeric proteins (MLC2v, TNNI3, and MYH7), ion channel proteins (Kir2.1, Nav1.5, Cav1.2, SERCA2a, and RyR), mitochondrial membrane potential, metabolomics, and action potential. Bobcat339, a selective and potent inhibitor of DNA demethylation, was used to determine whether AA promoted hiPSC-CM maturation through modulating DNA demethylation. Results: AA significantly increased MLC2v expression in PCBC-CMs, DP3-CMs, MLC2v-CMs, and RA induced atrial-like PCBC-CMs. AA treatment significantly increased mitochondrial mass, membrane potential, and amino acid and fatty acid metabolism in PCBC-CMs. Patch clamp studies showed that AA treatment induced PCBC-CMs and DP3-CMs adaptation to a ventricular-like phenotype. Bobcat339 inhibited MLC2v protein expression in AA treated PCBC-CMs and DP3-CMs. DNA demethylation inhibition was also associated with reduced TET1 and TET2 protein expressions and reduced accumulation of the oxidative product, 5 hmC, in both PCBC-CMs and DP3-CMs, in the presence of AA. Conclusions: Ascorbic acid promoted MLC2v protein expression and maturation of hiPSC-CMs. The effect of AA on hiPSC-CM was attenuated with inhibition of TET1/TET2 mediated DNA demethylation.

Investigation of the Antimicrobial, Physico-Chemical, Sensory Qualities of Ascorbic Acid and Effect on the Shelf-Life of Hot Smoked Mackerel (Scomber scombrus)

ABSTRACT The effectiveness of ascorbic acid in improving the quality and shelf life of processed (smoked) mackerel fillets was investigated. The fish were divided into four ascorbic acid (AA) treatment groups and smoked for 18 hours at a temperature between 120°C and 150°C. After 28 days, the fish were tested for proximate, biochemical, microbiological, and sensory status. Based on the tests conducted, fish treated with 15 mg L−1 AA showed better nutrient composition, biochemical, and sensory qualities, while Enterobacteriaceae spp counts declined with higher AA concentrations. The study revealed that AA improved mackerel fish and extended their shelf life.