Olivia G. Camp M.S. , Anuradha P. Goud Ph.D. , Pravin T. Goud M.D., Ph.D. , David Bai B.S. , Awoniyi Awonuga M.D. , Husam M. Abu-Soud Ph.D.
{"title":"随着年龄的增长,卵母细胞质量的下降与小鼠卵母细胞中一氧化氮合酶辅助因子、四氢生物蝶呤和锌的缺乏有关","authors":"Olivia G. Camp M.S. , Anuradha P. Goud Ph.D. , Pravin T. Goud M.D., Ph.D. , David Bai B.S. , Awoniyi Awonuga M.D. , Husam M. Abu-Soud Ph.D.","doi":"10.1016/j.xfss.2023.02.002","DOIUrl":null,"url":null,"abstract":"<div><h3>Objective</h3><p>To study the implications of decreased zinc and tetrahydrobiopterin (H<sub>4</sub>B) associated with chronological aging on oocyte quality using a mouse model. H<sub>4</sub><span>B and zinc are essential cofactors for nitric oxide synthase<span><span> (NOS), because they aid in electron transfer and dimeric stability, and their bioavailability is crucial in regulating NOS coupling. We have previously shown that sufficient levels of </span>nitric oxide (NO) are essential for maintaining oocyte quality and activation, and NO levels decrease in the oocyte as a function of age. Thus, it is plausible that zinc and H</span></span><sub>4</sub><span>B may decrease as a function of age, resulting in NOS dysfunction with subsequent depletion of NO. Additionally, increased production of reactive oxygen species from the monomeric form can further disrupt oocyte quality and NO bioavailability.</span></p></div><div><h3>Design</h3><p>Experimental laboratory study.</p></div><div><h3>Setting</h3><p>Laboratory.</p></div><div><h3>Animals</h3><p>B6D2F1 mice.</p></div><div><h3>Intervention(s)</h3><p>Sibling oocytes were retrieved from super-ovulated B6D2F1 mice from 3 age groups: 8–14 weeks (young breeders [YBs]), 48–52 weeks (retired breeders [RBs]), and 80–84 weeks (old animals [OAs]).</p></div><div><h3>Main Outcome Measure(s)</h3><p><span><span>Oocytes were scored for ooplasmic/spindle microtubule (MT) morphology, chromosomal alignment, and cortical granule (CG) intactness using </span>immunofluorescence<span> and confocal microscopy with 3 dimension image reconstruction and subjected to an high-performance liquid chromatography assay to measure the concentrations of H</span></span><sub>4</sub><span>B and its metabolites, as well as the zinc measurement using atomic absorption spectrophotometry.</span></p></div><div><h3>Result(s)</h3><p>Oocyte scoring showed a reduction in “good” quality oocyte percentage as age increases, with YB having the highest percentage of quality oocytes followed by RB and OA. The high-performance liquid chromatography analysis showed a significant progressive decrease in total H<sub>4</sub><span>B in RB and OA (0.00098 picogram (pg)/oocyte and 0.00069 pg/oocyte, respectively) compared with YB (0.00125 pg/oocyte). Atomic absorbance spectrophotometry revealed a significant progressive decrease in zinc concentration in RB and OA compared with YB (8.45 pg/oocyte and 5.82 pg/oocyte vs. 10.05 pg/oocyte, respectively).</span></p></div><div><h3>Conclusion(s)</h3><p>Age-related diminution in oocyte quality is paralleled by a decline in the levels of H<sub>4</sub><span>B and zinc. The resultant deficiency in the oocytes can lead to the inability of NOS to maintain dimerization. Consequent uncoupling of NOS generates superoxide instead of NO, which participates in a multitude of reactions contributing to oxidative stress. Therefore, dysfunction of NOS secondary to zinc and H</span><sub>4</sub>B loss is a major mechanism involved in reactive oxygen species generation and oocyte quality deterioration related to the chronological age.</p></div>","PeriodicalId":73012,"journal":{"name":"F&S science","volume":"4 2","pages":"Pages 114-120"},"PeriodicalIF":0.0000,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Diminishing oocyte quality with advancing age is associated with deficiency of nitric oxide synthase cofactors, tetrahydrobiopterin, and zinc, in mouse oocytes\",\"authors\":\"Olivia G. Camp M.S. , Anuradha P. Goud Ph.D. , Pravin T. Goud M.D., Ph.D. , David Bai B.S. , Awoniyi Awonuga M.D. , Husam M. Abu-Soud Ph.D.\",\"doi\":\"10.1016/j.xfss.2023.02.002\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><h3>Objective</h3><p>To study the implications of decreased zinc and tetrahydrobiopterin (H<sub>4</sub>B) associated with chronological aging on oocyte quality using a mouse model. H<sub>4</sub><span>B and zinc are essential cofactors for nitric oxide synthase<span><span> (NOS), because they aid in electron transfer and dimeric stability, and their bioavailability is crucial in regulating NOS coupling. We have previously shown that sufficient levels of </span>nitric oxide (NO) are essential for maintaining oocyte quality and activation, and NO levels decrease in the oocyte as a function of age. Thus, it is plausible that zinc and H</span></span><sub>4</sub><span>B may decrease as a function of age, resulting in NOS dysfunction with subsequent depletion of NO. Additionally, increased production of reactive oxygen species from the monomeric form can further disrupt oocyte quality and NO bioavailability.</span></p></div><div><h3>Design</h3><p>Experimental laboratory study.</p></div><div><h3>Setting</h3><p>Laboratory.</p></div><div><h3>Animals</h3><p>B6D2F1 mice.</p></div><div><h3>Intervention(s)</h3><p>Sibling oocytes were retrieved from super-ovulated B6D2F1 mice from 3 age groups: 8–14 weeks (young breeders [YBs]), 48–52 weeks (retired breeders [RBs]), and 80–84 weeks (old animals [OAs]).</p></div><div><h3>Main Outcome Measure(s)</h3><p><span><span>Oocytes were scored for ooplasmic/spindle microtubule (MT) morphology, chromosomal alignment, and cortical granule (CG) intactness using </span>immunofluorescence<span> and confocal microscopy with 3 dimension image reconstruction and subjected to an high-performance liquid chromatography assay to measure the concentrations of H</span></span><sub>4</sub><span>B and its metabolites, as well as the zinc measurement using atomic absorption spectrophotometry.</span></p></div><div><h3>Result(s)</h3><p>Oocyte scoring showed a reduction in “good” quality oocyte percentage as age increases, with YB having the highest percentage of quality oocytes followed by RB and OA. The high-performance liquid chromatography analysis showed a significant progressive decrease in total H<sub>4</sub><span>B in RB and OA (0.00098 picogram (pg)/oocyte and 0.00069 pg/oocyte, respectively) compared with YB (0.00125 pg/oocyte). Atomic absorbance spectrophotometry revealed a significant progressive decrease in zinc concentration in RB and OA compared with YB (8.45 pg/oocyte and 5.82 pg/oocyte vs. 10.05 pg/oocyte, respectively).</span></p></div><div><h3>Conclusion(s)</h3><p>Age-related diminution in oocyte quality is paralleled by a decline in the levels of H<sub>4</sub><span>B and zinc. The resultant deficiency in the oocytes can lead to the inability of NOS to maintain dimerization. Consequent uncoupling of NOS generates superoxide instead of NO, which participates in a multitude of reactions contributing to oxidative stress. Therefore, dysfunction of NOS secondary to zinc and H</span><sub>4</sub>B loss is a major mechanism involved in reactive oxygen species generation and oocyte quality deterioration related to the chronological age.</p></div>\",\"PeriodicalId\":73012,\"journal\":{\"name\":\"F&S science\",\"volume\":\"4 2\",\"pages\":\"Pages 114-120\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2023-05-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"F&S science\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S2666335X23000101\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"F&S science","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2666335X23000101","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Diminishing oocyte quality with advancing age is associated with deficiency of nitric oxide synthase cofactors, tetrahydrobiopterin, and zinc, in mouse oocytes
Objective
To study the implications of decreased zinc and tetrahydrobiopterin (H4B) associated with chronological aging on oocyte quality using a mouse model. H4B and zinc are essential cofactors for nitric oxide synthase (NOS), because they aid in electron transfer and dimeric stability, and their bioavailability is crucial in regulating NOS coupling. We have previously shown that sufficient levels of nitric oxide (NO) are essential for maintaining oocyte quality and activation, and NO levels decrease in the oocyte as a function of age. Thus, it is plausible that zinc and H4B may decrease as a function of age, resulting in NOS dysfunction with subsequent depletion of NO. Additionally, increased production of reactive oxygen species from the monomeric form can further disrupt oocyte quality and NO bioavailability.
Design
Experimental laboratory study.
Setting
Laboratory.
Animals
B6D2F1 mice.
Intervention(s)
Sibling oocytes were retrieved from super-ovulated B6D2F1 mice from 3 age groups: 8–14 weeks (young breeders [YBs]), 48–52 weeks (retired breeders [RBs]), and 80–84 weeks (old animals [OAs]).
Main Outcome Measure(s)
Oocytes were scored for ooplasmic/spindle microtubule (MT) morphology, chromosomal alignment, and cortical granule (CG) intactness using immunofluorescence and confocal microscopy with 3 dimension image reconstruction and subjected to an high-performance liquid chromatography assay to measure the concentrations of H4B and its metabolites, as well as the zinc measurement using atomic absorption spectrophotometry.
Result(s)
Oocyte scoring showed a reduction in “good” quality oocyte percentage as age increases, with YB having the highest percentage of quality oocytes followed by RB and OA. The high-performance liquid chromatography analysis showed a significant progressive decrease in total H4B in RB and OA (0.00098 picogram (pg)/oocyte and 0.00069 pg/oocyte, respectively) compared with YB (0.00125 pg/oocyte). Atomic absorbance spectrophotometry revealed a significant progressive decrease in zinc concentration in RB and OA compared with YB (8.45 pg/oocyte and 5.82 pg/oocyte vs. 10.05 pg/oocyte, respectively).
Conclusion(s)
Age-related diminution in oocyte quality is paralleled by a decline in the levels of H4B and zinc. The resultant deficiency in the oocytes can lead to the inability of NOS to maintain dimerization. Consequent uncoupling of NOS generates superoxide instead of NO, which participates in a multitude of reactions contributing to oxidative stress. Therefore, dysfunction of NOS secondary to zinc and H4B loss is a major mechanism involved in reactive oxygen species generation and oocyte quality deterioration related to the chronological age.