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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">akusherstvo</journal-id><journal-title-group><journal-title xml:lang="en">Obstetrics, Gynecology and Reproduction</journal-title><trans-title-group xml:lang="ru"><trans-title>Акушерство, Гинекология и Репродукция</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2313-7347</issn><issn pub-type="epub">2500-3194</issn><publisher><publisher-name>IRBIS LLC</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.17749/2313-7347/ob.gyn.rep.2024.517</article-id><article-id custom-type="elpub" pub-id-type="custom">akusherstvo-2227</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ОRIGINAL ARTICLES</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject></subj-group></article-categories><title-group><article-title>Effect of synthetic and reduced folic acid on methionine metabolism parameters in various experimental models with Wistar rats</article-title><trans-title-group xml:lang="ru"><trans-title>Влияние синтетической и восстановленной формы фолиевой кислоты на показатели метионинового обмена в эксперименте на различных моделях крыс линии Wistar</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0007-4567-7831</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Сазонова</surname><given-names>А. П.</given-names></name><name name-style="western" xml:lang="en"><surname>Sazonova</surname><given-names>A. P.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Сазонова Анастасия Павловна</p><p>99034 Санкт-Петербург, Менделеевская линия, д. 3</p><p>Scopus Author ID: 58729079700. WoS ResearcherID: KIL-6249-2024</p></bio><bio xml:lang="en"><p>Anastasiia P. Sazonova, MD</p><p>Scopus Author ID: 58729079700. WoS ResearcherID: KIL-6249-2024</p></bio><email xlink:type="simple">nastenka.sazonova.97@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-1951-8312</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Милютина</surname><given-names>Ю. П.</given-names></name><name name-style="western" xml:lang="en"><surname>Milyutina</surname><given-names>Yu. P.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Милютина Юлия Павловна, к.б.н.</p><p>99034 Санкт-Петербург, Менделеевская линия, д. 3</p><p>Scopus Author ID: 24824836300. WoS ResearcherID: ААЕ-6182-2019</p></bio><bio xml:lang="en"><p>Yuliya P. Milyutina, MD, PhD in Biology</p><p>Scopus Author ID: 24824836300. WoS ResearcherID: ААЕ-6182-2019</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-6542-5953</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Беспалова</surname><given-names>О. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Bespalova</surname><given-names>O. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Беспалова Олеся Николаевна, д.м.н.</p><p>99034 Санкт-Петербург, Менделеевская линия, д. 3</p><p>Scopus Author ID: 57189999252. WoS ResearcherID: D-3880-2018</p></bio><bio xml:lang="en"><p>Olesya N. Bespalova, MD</p><p>Scopus Author ID: 57189999252. WoS ResearcherID: D-3880-2018</p><p> </p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-4116-0222</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Пачулия</surname><given-names>О. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Pachuliia</surname><given-names>O. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Пачулия Ольга Владимировна, к.м.н.</p><p>99034 Санкт-Петербург, Менделеевская линия, д. 3</p><p>Scopus Author ID: 57299197900. WoS ResearcherID: Q-7819-2018</p></bio><bio xml:lang="en"><p>Olga V. Pachuliia, MD, PhD</p><p>Scopus Author ID: 57299197900. WoS ResearcherID: Q-7819-2018</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-0576-9690</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Залозняя</surname><given-names>И. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Zalozniaia</surname><given-names>I. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Залозняя Ирина Владимировна</p><p>99034 Санкт-Петербург, Менделеевская линия, д. 3</p><p>Scopus Author ID: 56510246800. WoS ResearcherID: ABB-7622-2020</p></bio><bio xml:lang="en"><p>Irina V. Zalozniaia, MD</p><p>Scopus Author ID: 56510246800. WoS ResearcherID: ABB-7622-2020</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-0365-8532</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кореневский</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Korenevsky</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кореневский Андрей Валентинович, д.б.н.</p><p>99034 Санкт-Петербург, Менделеевская линия, д. 3</p><p>Scopus Author ID: 6037015200. WoS ResearcherID: K-3444-2013</p></bio><bio xml:lang="en"><p>Andrew V. Korenevsky, MD, Dr Sci Biol</p><p>Scopus Author ID: 6037015200. WoS ResearcherID: K-3444-2013</p></bio><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГБНУ «Научно-исследовательский институт акушерства, гинекологии и репродуктологии имени Д.О. Отта»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Ott Research Institute of Obstetrics, Gynecology and Reproductology</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2024</year></pub-date><pub-date pub-type="epub"><day>04</day><month>11</month><year>2024</year></pub-date><volume>18</volume><issue>5</issue><elocation-id>658–666</elocation-id><permissions><copyright-statement>Copyright &amp;#x00A9; Sazonova A.P., Milyutina Y.P., Bespalova O.N., Pachuliia O.V., Zalozniaia I.V., Korenevsky A.V., 2024</copyright-statement><copyright-year>2024</copyright-year><copyright-holder xml:lang="ru">Сазонова А.П., Милютина Ю.П., Беспалова О.Н., Пачулия О.В., Залозняя И.В., Кореневский А.В.</copyright-holder><copyright-holder xml:lang="en">Sazonova A.P., Milyutina Y.P., Bespalova O.N., Pachuliia O.V., Zalozniaia I.V., Korenevsky A.V.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.gynecology.su/jour/article/view/2227">https://www.gynecology.su/jour/article/view/2227</self-uri><abstract><sec><title>Introduction</title><p>Introduction. Currently, folic acid preparations are administered during preconception period in an empirical manner. Along with synthetic folic acid, there also exists its reduced counterpart 5-methyltetrahydrofolate (5-MTHF). Manufacturers of the latter claim that 5-MTHF overcomes metabolic defects due to c.665C&gt;T gene polymorphism in the methylenetetrahydrofolate reductase (MTHFR), and therefore it is superior to synthetic folic acid (pteroylmonoglutamic acid, PGA). However, no large-scale studies to confirm this hypothesis have been conducted yet.</p></sec><sec><title>Aim</title><p>Aim: to assess an effect of various folic acid preparations on methionine metabolism in experimental models with Wistar rats.</p></sec><sec><title>Materials and Methods</title><p>Materials and Methods. A chronic hyperhomocysteinemia (HHC) was induced in sexually mature female Wistar rats by daily methionine supplementation. After HHC development, experimental animals were administered PGA or 5-MTHF. Some animals without HHC also received folic acid supplements or water. Blood samples were collected at 3 time points (1, 2 weeks and 1.5 months after folate preparation administration) to quantitate level of homocysteine (HC), plasma folic acid and red blood cell count.</p></sec><sec><title>Results</title><p>Results. It was verified that HHC developed in mature Wistar rats after methionine supplementation, with HC level being significantly higher (p &lt; 0.05) than in control group. Use of folic acid supplements during HHC caused by methionine load did not result in lower HC level. In experimental animals administered PGA or 5-MTHF, blood serum folic acid level and red blood cell count did not change upon longer drug administration. No advantage for 5-MTHF vs. synthetic folic acid on HC levels and erythrocyte folate accumulation was observed. Instead of the expected decline in HC level in HHC models related to the examined folate preparations, the opposite effect was obtained. In case of pre-existing non-folate-dependent chronic HHC, HC level increased from time point 1 to time point 3.</p></sec><sec><title>Conclusion</title><p>Conclusion. Chronic non-folate-dependent HHC, induced by chronic oral methionine was self-limiting in experimental models; additional folate supplementation resulted in sharply increased plasma HC level. Experimental models with Wistar rats showed that no further accumulation of folic acid occurs upon its optimal levels in plasma and red blood cells. The study revealed no advantages for 5-MTHF over synthetic folic acid in lowering blood plasma HC level and folic acid accumulation in erythrocytes.</p></sec></abstract><trans-abstract xml:lang="ru"><sec><title>Введение</title><p>Введение. В настоящее время назначение препаратов фолиевой кислоты в прегравидарном периоде является эмпирическим. Наряду с синтетической фолиевой кислотой существует восстановленная форма фолиевой кислоты – 5-метилтетрагидрофолат (англ. 5-methyltetrahydrofolate, 5-MTHF). Производители данной формы заявляют, что 5-MTHF преодолевает метаболические дефекты, вызванные полиморфизмом в гене метилентетрагидрофолатредуктазы (англ. methylenetetrahydrofolate reductase, MTHFR) c.665C&gt;T, в связи с чем его применение имеет преимущества перед синтетической фолиевой кислотой (птероилмоноглутаминовая кислота, ПГА). Однако крупных исследований, подтверждающих данную гипотезу, не проводилось.</p></sec><sec><title>Цель</title><p>Цель: оценить влияние различных препаратов фолиевой кислоты на показатели метионинового обмена в экспериментальных моделях крыс линии Wistar.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. Половозрелым самкам крыс линии Wistar было создано состояние хронической гипергомоцистеинемии (ГГЦ) с помощью ежедневной метиониновой нагрузки. После развития состояния ГГЦ экспериментальным животным вводили ПГА либо 5-MTHF. Часть животных без ГГЦ также получала препараты фолиевой кислоты или воду. В 3 этапа (через 1, 2 нед и 1,5 мес от добавления фолатов) был выполнен отбор проб крови с измерением уровня гомоцистеина (ГЦ), концентрации фолиевой кислоты в плазме и в эритроцитах.</p></sec><sec><title>Результаты</title><p>Результаты. При метиониновой нагрузке у половозрелых крыс наблюдалось развитие ГГЦ, при котором уровень ГЦ был значимо выше (p &lt; 0,05) по сравнению со значениями в контрольной группе. Добавление препаратов фолиевой кислоты на фоне ГГЦ, вызванной метиониновой нагрузкой, не привело к снижению концентрации ГЦ. У экспериментальных животных, которым вводили ПГА или 5-MTHF, концентрация фолиевой кислоты в сыворотке крови и эритроцитах не изменялась с увеличением срока введения препаратов. Не установлено преимуществ 5-MTHF перед синтетической фолиевой кислотой в отношении уровня ГЦ и накопления фолиевой кислоты в эритроцитах. Вместо ожидаемого снижения уровня ГЦ у ГГЦ моделей под действием исследуемых фолатов получен противоположный эффект. При уже имеющейся нефолатзависимой хронической ГГЦ уровень ГЦ нарастал от 1-го к 3-му этапу.</p></sec><sec><title>Заключение</title><p>Заключение. Хроническая нефолатзависимая ГГЦ, вызванная с помощью постоянного перорального введения метионина, купировалась у экспериментальных моделей самостоятельно, при этом дополнительное добавление фолатов способствовало росту ГЦ в плазме крови. На экспериментальных моделях крыс с нормальным уровнем фолиевой кислоты в эритроцитах было показано, что добавление в рацион препаратов фолиевой кислоты не приводит к ее дальнейшему накоплению. Исследование не показало преимуществ 5-МТГФ перед синтетической фолиевой кислотой в отношении снижения уровня ГЦ в плазме крови и накопления фолиевой кислоты в эритроцитах.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>синтетическая фолиевая кислота</kwd><kwd>5-метилтетрагидрофолат</kwd><kwd>5-MTHF</kwd><kwd>экспериментальная модель</kwd><kwd>фолатный цикл</kwd><kwd>гипергомоцистеинемия</kwd><kwd>ГГЦ</kwd></kwd-group><kwd-group xml:lang="en"><kwd>synthetic folic acid</kwd><kwd>5-methyltetrahydrofolate</kwd><kwd>5-MTHF</kwd><kwd>experimental model</kwd><kwd>folate cycle</kwd><kwd>hyperhomocysteinemia</kwd><kwd>HHC</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Seremak-Mrozikiewicz A. Metafolin – alternative for folate deficiency supplementation in pregnant women. 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