agxАндрология и генитальная хирургияAndrology and Genital Surgery2070-97812412-890210.17650/2070-9781-2017-18-1-48-61agx-224Research ArticleОРИГИНАЛЬНЫЕ СТАТЬИORIGINAL REPORTНАРУШЕНИЕ КОНДЕНСАЦИИ ХРОМАТИНА СПЕРМАТОЗОИДОВ И ФРАГМЕНТАЦИЯ ДНК СПЕРМАТОЗОИДОВ: ЕСТЬ ЛИ КОРРЕЛЯЦИЯ?ABNORMAL CHROMATIN CONDENSATION IN SPERMATOZOA AND DNA FRAGMENTATION IN SPERMATOZOA: IS THERE A CORRELATION?БрагинаЕ. Е.BraginaE. E.

Контакты: Елизавета Ефимовна Брагина bragor@mail.ru 

119992 Москва, Ленинские горы, 1, стр. 40

bragor@mail.ruАрифулинЕ. А.ArifulinE. A.ЛазареваЕ. М.LazarevaE. M.ЛелековаМ. А.LelekovaM. A.КоломиецО. Л.KolomietsO. L.ЧоговадзеА. Г.ChogovadzeA. G.СорокинаТ. М.SorokinaT. M.КурилоЛ. Ф.KuriloL. F.ПоляковВ. Ю.PolyakovV. Yu.Научно-исследовательский институт физико-химической биологии им. А.Н. Белозерского ФГБОУ ВПО «Московский государственный университет им. М.В. Ломоносова»; ФГБНУ «Медико-генетический научный центр»РоссияA.N. Belozersky Research Institute of Physico-Chemical Biology, Lomonosov Moscow State University; Research Center of Medical GeneticsRussian FederationНаучно-исследовательский институт физико-химической биологии им. А.Н. Белозерского ФГБОУ ВПО «Московский государственный университет им. М.В. Ломоносова»РоссияA.N. Belozersky Research Institute of Physico-Chemical Biology, Lomonosov Moscow State UniversityRussian FederationБиологический факультет ФГБОУ ВПО «Московский государственный университет им. М.В. Ломоносова»РоссияBiological Faculty, Lomonosov Moscow State UniversityRussian FederationООО «ЦГРМ ИСКЧ», Банк репродуктивных клеток и тканей «Репробанк»РоссияRegenerative and Genetic Medical Center of the Human Stem Cell Institute, reproductive cell and tissue bank “Reprobank”Russian FederationФГБУН «Институт общей генетики им. Н.И. Вавилова» РАНРоссияVavilov Institute of General Genetics, Russian Academy of SciencesRussian FederationФГБНУ «Медико-генетический научный центр»РоссияResearch Center of Medical GeneticsRussian Federation2017020520171814861Copyright © Брагина Е.Е., Арифулин Е.А., Лазарева Е.М., Лелекова М.А., Коломиец О.Л., Чоговадзе А.Г., Сорокина Т.М., Курило Л.Ф., Поляков В.Ю., 20172017Брагина Е.Е., Арифулин Е.А., Лазарева Е.М., Лелекова М.А., Коломиец О.Л., Чоговадзе А.Г., Сорокина Т.М., Курило Л.Ф., Поляков В.Ю.Bragina E.E., Arifulin E.A., Lazareva E.M., Lelekova M.A., Kolomiets O.L., Chogovadze A.G., Sorokina T.M., Kurilo L.F., Polyakov V.Y.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://agx.elpub.ru/jour/article/view/224Введение

Введение. В последнее десятилетие появилось понимание двоякой природы повреждения генетического аппарата сперматозоидов: нарушение конденсации хроматина («незрелый» хроматин, НХ), связанное с нарушенной протаминизацией и приводящее к нарушению эпигенетической регуляции раннего эмбриогенеза, и нарушение целостности ДНК сперматозоидов – фрагментация ДНК (ФДС).

Цель исследования – изучение корреляции между нарушением конденсации хроматина сперматозоидов и ФДС.

Материалы и методы

Материалы и методы. Проводили исследование сперматозоидов 54 фертильных мужчин (1-я группа, контрольная), 46 пациентов с первичным бесплодием (2-я группа) и 111 пациентов, в анамнезе жен которых имели место аномалии беременности либо неудачи применения вспомогательных репродуктивных технологий (ВРТ) – остановка развития эмбриона (3-я группа). Наличие НХ выявляли методом количественного электронно-микроскопического исследования, ФДС – методом TUNEL. Исследование НХ и ФДС в одном и том же сперматозоиде проводили методом корреляционной микроскопии (TUNEL с последующим ультраструктурным изучением маркированных клеток).

Результаты

Результаты. Содержание сперматозоидов с НХ статистически достоверно отличалось от контрольной в 3-й группе (29,26 ± 13,49 против 22,43 ± 9,54; p = 0,006). Содержание НХ во 2-й группе выше, чем в 1-й, но разница статистически недостоверна (p = 0,061). Достоверные различия по содержанию сперматозоидов с остаточной цитоплазмой на головке отмечены между группой фертильных мужчин и 2-й и 3-й группами (p = 0,0001 и p = 0,0006 соответственно) и на шейке (p = 0,0002 и p = 0,0003 соответственно). Содержание сперматозоидов с ФДС статистически достоверно отличалось от контрольной во 2-й группе (21,40 ± 11,88 против 13,70 ± 7,00, p = 0,03) и не отличалось в 3-й группе. Очень слабая корреляция между содержанием сперматозоидов с ФДС и сперматозоидов с НХ отмечена во всех 3 группах (r = 0,18, r = 0,33 и r = 0,01 соответственно). Методом корреляционной электронной микроскопии исследовано 46 сперматозоидов, из них 23 с НХ и 23 – с конденсированным хроматином. В 11 из 23 сперматозоидов с НХ выявлена ФДС. В сперматозоидах с конденсированным хроматином ФДС определена в 6 сперматозоидах.

Заключение

Заключение. ФДС и нарушение конденсации хроматина – в высокой степени независимые параметры, которые должны учитываться при выяснении генезиса бесплодия. НХ чаще обнаруживается в сперматозоидах пациентов, у жен которых в анамнезе – нарушение эмбриогенеза. ФДС чаще выявляется при первичном бесплодии.

Introduction

Introduction. In the last decade, an understanding of the two-fold nature of genetic apparatus damage in spermatozoa has emerged: abnormal chromatin condensation (“immature” chromatin, ICH) related to defective protaminization and leading to altered epigenetic regulation of the early embryogenesis, and disruption of DNA integrity, i. e. DNA fragmentation (DFS).

Objective

Objective. Study of the correlation between abnormal chromatin condensation in spermatozoa and DFS.

Materials and methods

Materials and methods. The study included spermatozoa of 54 fertile males (1st group, control), 46 patients with primary infertility (2nd group), and 111 patients whose wives had a history of pregnancy abnormalities or failures of the assisted reproductive technology (ART), i. e. arrested embryonic development (3rd group). Presence of ICH was identified by quantitative electron microscopy, presence of DFS by TUNEL. Study of ICH and DFS in the same spermatozoon was conducted using correlation microscopy (TUNEL with subsequent ultrastructural analysis of the labeled cells).

Results

Results. The number of ICH spermatozoa significantly differed in the 3rd group from the control group (29.26 ± 13.49 vs. 22.43 ± 9.54; p = 0.006). The number of ICH spermatozoa in the 2nd group was higher than in the control group, but the difference wasn’t statistically significant (p = 0.061). A significant difference in the number of spermatozoa with residual cytoplasm on the head was observed between the fertile group and 2nd and 3rd groups (p = 0.0001 and p = 0.0006, respectively) and on the neck (p = 0.0002 and p = 0.0003, respectively). Number of DFS spermatozoa in the second group significantly differed from the control (21.40 ± 11.88 vs. 13.70 ± 7.00, p = 0.03), but this difference wasn’t observed for the 3rd group. A very weak correlation between the number of DFS and ICH spermatozoa was observed in all three groups (r = 0.18, r = 0.33, and r = 0.01, respectively). Forty-six (46) spermatozoa were studied using correlation microscopy, among them 23 were DFS and 23 were ICH. In 11 of 23 HDS spermatozoa DFS was observed. In spermatozoa with condensed chromatin, DFS was identified in 6 spermatozoa.

Conclusion

Conclusion. DFS and abnormal chromatin condensation are highly independent parameters, which should be considered during identification of the cause of infertility. ICH is more frequent in spermatozoa of patients whose wives have a history of embryogenesis abnormalities. DNS is more frequent in primary infertility.

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The authors declare that there are no conflicts of interest present.