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NAD(P)H: quinone oxidoreductase 1 deficiency conjoint with marginal vitamin C deficiency causes cigarette smoke induced myelodysplastic syndromes.

Das A, Dey N, Ghosh A, Das T, Chatterjee IB - PLoS ONE (2011)

Bottom Line: Apoptosis precedes MDS but disappears later with marked decrease in the p53 protein.However, after the onset of MDS vitamin C becomes ineffective.Our results suggest that human smokers having NQO1 deficiency combined with marginal vitamin C deficiency are likely to be at high risk for developing MDS and that intake of a moderately large dose of vitamin C would prevent MDS.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology and Dr. B. C. Guha Centre for Genetic Engineering and Biotechnology, Calcutta University College of Science, Kolkata, West Bengal, India.

ABSTRACT

Background: The etiology of myelodysplastic syndromes (MDS) is largely unknown. Exposure to cigarette smoke (CS) is reported to be associated with MDS risk. There is inconsistent evidence that deficiency of NAD(P)H-quinone: oxidoreductase 1 (NQO1) increases the risk of MDS. Earlier we had shown that CS induces toxicity only in marginal vitamin C-deficient guinea pigs but not in vitamin C-sufficient ones. We therefore considered that NQO1 deficiency along with marginal vitamin C deficiency might produce MDS in CS-exposed guinea pigs.

Methodology and principal findings: Here we show that CS exposure for 21 days produces MDS in guinea pigs having deficiency of NQO1 (fed 3 mg dicoumarol/day) conjoint with marginal vitamin C deficiency (fed 0.5 mg vitamin C/day). As evidenced by morphology, histology and cytogenetics, MDS produced in the guinea pigs falls in the category of refractory cytopenia with unilineage dysplasia (RCUD): refractory anemia; refractory thrombocytopenia that is associated with ring sideroblasts, micromegakaryocytes, myeloid hyperplasia and aneuploidy. MDS is accompanied by increased CD34(+) cells and oxidative stress as shown by the formation of protein carbonyls and 8-oxodeoxyguanosine. Apoptosis precedes MDS but disappears later with marked decrease in the p53 protein. MDS produced in the guinea pigs are irreversible. MDS and all the aforesaid pathophysiological events do not occur in vitamin C-sufficient guinea pigs. However, after the onset of MDS vitamin C becomes ineffective.

Conclusions and significance: CS exposure causes MDS in guinea pigs having deficiency of NQO1 conjoint with marginal vitamin C deficiency. The syndromes are not produced in singular deficiency of NQO1 or marginal vitamin C deficiency. Our results suggest that human smokers having NQO1 deficiency combined with marginal vitamin C deficiency are likely to be at high risk for developing MDS and that intake of a moderately large dose of vitamin C would prevent MDS.

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Assessment of apoptosis by TUNEL assay, flow cytometry and cell signaling in bone marrow cells of guinea pigs.(Panel A) TUNEL assay of bone marrow cells. The rows were stained with fluorescein labeled dUTP and 4, 6-diamidino-2-phenylindole (DAPI), respectively; green fluorescence indicates TUNEL positive cells (magnification 200×). (Panel B) Quantitative evaluation of TUNEL positive cells; bars (means ± SD, n = 6) over the respective columns represent TUNEL positive cells, * significantly different (p<0.05) with respect to 0 day, ** significantly different (p<0.05) from 14 days treatment. (Panel C) Flow cytometry analyses of bone marrow cells using Annexin V-FITC fluorescence (Y-axis) vs PI (X-axis); quadrants: lower left, viable cells; upper left, apoptotic cells; upper right, late apoptotic and lower right, necrotic cells. (Panel D) p53 status in the bone marrow cells at different time. (Panel E) and (Panel F) Immunoblots of p-p53 (phospho-p53), Bax, Bcl-2, caspase 3 (C3), cleaved caspase 3 (CC3). (Panel G) and (Panel H) Immunoblots of TNF-α, caspase 8 (C8) and cleaved caspase 8 (CC8). Vit C means vitamin C.
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pone-0020590-g003: Assessment of apoptosis by TUNEL assay, flow cytometry and cell signaling in bone marrow cells of guinea pigs.(Panel A) TUNEL assay of bone marrow cells. The rows were stained with fluorescein labeled dUTP and 4, 6-diamidino-2-phenylindole (DAPI), respectively; green fluorescence indicates TUNEL positive cells (magnification 200×). (Panel B) Quantitative evaluation of TUNEL positive cells; bars (means ± SD, n = 6) over the respective columns represent TUNEL positive cells, * significantly different (p<0.05) with respect to 0 day, ** significantly different (p<0.05) from 14 days treatment. (Panel C) Flow cytometry analyses of bone marrow cells using Annexin V-FITC fluorescence (Y-axis) vs PI (X-axis); quadrants: lower left, viable cells; upper left, apoptotic cells; upper right, late apoptotic and lower right, necrotic cells. (Panel D) p53 status in the bone marrow cells at different time. (Panel E) and (Panel F) Immunoblots of p-p53 (phospho-p53), Bax, Bcl-2, caspase 3 (C3), cleaved caspase 3 (CC3). (Panel G) and (Panel H) Immunoblots of TNF-α, caspase 8 (C8) and cleaved caspase 8 (CC8). Vit C means vitamin C.

Mentions: Figure 3, A and B show that in the guinea pigs fed 0.5 mg vitamin C and 3 mg DC/day, there is progressive increase in the number of TUNEL positive cells in the bone marrow after exposure to CS for 7 and 14 days. However, after continuation of CS exposure for 21 days, the TUNEL positive cells have disappeared, which is accompanied by occurrence of MDS. The TUNEL positive cells are also absent when the DC-treated CS-exposed guinea pigs are fed 15 mg vitamin C/day. Since 15 mg vitamin C prevents MDS (Figure 2), the results would indicate that a moderately high dose of vitamin C prevents apoptosis and MDS.


NAD(P)H: quinone oxidoreductase 1 deficiency conjoint with marginal vitamin C deficiency causes cigarette smoke induced myelodysplastic syndromes.

Das A, Dey N, Ghosh A, Das T, Chatterjee IB - PLoS ONE (2011)

Assessment of apoptosis by TUNEL assay, flow cytometry and cell signaling in bone marrow cells of guinea pigs.(Panel A) TUNEL assay of bone marrow cells. The rows were stained with fluorescein labeled dUTP and 4, 6-diamidino-2-phenylindole (DAPI), respectively; green fluorescence indicates TUNEL positive cells (magnification 200×). (Panel B) Quantitative evaluation of TUNEL positive cells; bars (means ± SD, n = 6) over the respective columns represent TUNEL positive cells, * significantly different (p<0.05) with respect to 0 day, ** significantly different (p<0.05) from 14 days treatment. (Panel C) Flow cytometry analyses of bone marrow cells using Annexin V-FITC fluorescence (Y-axis) vs PI (X-axis); quadrants: lower left, viable cells; upper left, apoptotic cells; upper right, late apoptotic and lower right, necrotic cells. (Panel D) p53 status in the bone marrow cells at different time. (Panel E) and (Panel F) Immunoblots of p-p53 (phospho-p53), Bax, Bcl-2, caspase 3 (C3), cleaved caspase 3 (CC3). (Panel G) and (Panel H) Immunoblots of TNF-α, caspase 8 (C8) and cleaved caspase 8 (CC8). Vit C means vitamin C.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3105086&req=5

pone-0020590-g003: Assessment of apoptosis by TUNEL assay, flow cytometry and cell signaling in bone marrow cells of guinea pigs.(Panel A) TUNEL assay of bone marrow cells. The rows were stained with fluorescein labeled dUTP and 4, 6-diamidino-2-phenylindole (DAPI), respectively; green fluorescence indicates TUNEL positive cells (magnification 200×). (Panel B) Quantitative evaluation of TUNEL positive cells; bars (means ± SD, n = 6) over the respective columns represent TUNEL positive cells, * significantly different (p<0.05) with respect to 0 day, ** significantly different (p<0.05) from 14 days treatment. (Panel C) Flow cytometry analyses of bone marrow cells using Annexin V-FITC fluorescence (Y-axis) vs PI (X-axis); quadrants: lower left, viable cells; upper left, apoptotic cells; upper right, late apoptotic and lower right, necrotic cells. (Panel D) p53 status in the bone marrow cells at different time. (Panel E) and (Panel F) Immunoblots of p-p53 (phospho-p53), Bax, Bcl-2, caspase 3 (C3), cleaved caspase 3 (CC3). (Panel G) and (Panel H) Immunoblots of TNF-α, caspase 8 (C8) and cleaved caspase 8 (CC8). Vit C means vitamin C.
Mentions: Figure 3, A and B show that in the guinea pigs fed 0.5 mg vitamin C and 3 mg DC/day, there is progressive increase in the number of TUNEL positive cells in the bone marrow after exposure to CS for 7 and 14 days. However, after continuation of CS exposure for 21 days, the TUNEL positive cells have disappeared, which is accompanied by occurrence of MDS. The TUNEL positive cells are also absent when the DC-treated CS-exposed guinea pigs are fed 15 mg vitamin C/day. Since 15 mg vitamin C prevents MDS (Figure 2), the results would indicate that a moderately high dose of vitamin C prevents apoptosis and MDS.

Bottom Line: Apoptosis precedes MDS but disappears later with marked decrease in the p53 protein.However, after the onset of MDS vitamin C becomes ineffective.Our results suggest that human smokers having NQO1 deficiency combined with marginal vitamin C deficiency are likely to be at high risk for developing MDS and that intake of a moderately large dose of vitamin C would prevent MDS.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology and Dr. B. C. Guha Centre for Genetic Engineering and Biotechnology, Calcutta University College of Science, Kolkata, West Bengal, India.

ABSTRACT

Background: The etiology of myelodysplastic syndromes (MDS) is largely unknown. Exposure to cigarette smoke (CS) is reported to be associated with MDS risk. There is inconsistent evidence that deficiency of NAD(P)H-quinone: oxidoreductase 1 (NQO1) increases the risk of MDS. Earlier we had shown that CS induces toxicity only in marginal vitamin C-deficient guinea pigs but not in vitamin C-sufficient ones. We therefore considered that NQO1 deficiency along with marginal vitamin C deficiency might produce MDS in CS-exposed guinea pigs.

Methodology and principal findings: Here we show that CS exposure for 21 days produces MDS in guinea pigs having deficiency of NQO1 (fed 3 mg dicoumarol/day) conjoint with marginal vitamin C deficiency (fed 0.5 mg vitamin C/day). As evidenced by morphology, histology and cytogenetics, MDS produced in the guinea pigs falls in the category of refractory cytopenia with unilineage dysplasia (RCUD): refractory anemia; refractory thrombocytopenia that is associated with ring sideroblasts, micromegakaryocytes, myeloid hyperplasia and aneuploidy. MDS is accompanied by increased CD34(+) cells and oxidative stress as shown by the formation of protein carbonyls and 8-oxodeoxyguanosine. Apoptosis precedes MDS but disappears later with marked decrease in the p53 protein. MDS produced in the guinea pigs are irreversible. MDS and all the aforesaid pathophysiological events do not occur in vitamin C-sufficient guinea pigs. However, after the onset of MDS vitamin C becomes ineffective.

Conclusions and significance: CS exposure causes MDS in guinea pigs having deficiency of NQO1 conjoint with marginal vitamin C deficiency. The syndromes are not produced in singular deficiency of NQO1 or marginal vitamin C deficiency. Our results suggest that human smokers having NQO1 deficiency combined with marginal vitamin C deficiency are likely to be at high risk for developing MDS and that intake of a moderately large dose of vitamin C would prevent MDS.

Show MeSH
Related in: MedlinePlus