Effects of cigarette smoking on semen quality, reproductive hormone levels, metabolic profile, zinc and sperm DNA fragmentation in men: results from a population-based study

Abstract

BackgroundCigarette smoking seems to have a negative impact on men’s reproductive health, but our knowledge of its effects on the reproductive function of Russian men is still very limited. The purpose of this study was to evaluate the effect of cigarette smoking on semen quality, including sperm DNA fragmentation, hormonal, zinc and metabolic status in young men from the general multi-ethnic Russian population (n=1,222, median age 23 years) and to find out the ethno-specific effects of smoking by comparing male groups of different ethnicity.MethodsEach participant filled out a standardized questionnaire, provided one blood and semen sample. Semen parameters, serum reproductive hormones, lipids, glucose, uric acid and seminal zinc were analyzed. Participants were classified as smokers (n=450) and non-smokers (n=772), and smokers were stratified into moderate (≤10 cigarettes/day) and heavy (>10 cigarettes/day) smokers.ResultsIn the entire study population, heavy smokers were characterized by a decrease in semen volume, total sperm count, sperm concentration and motility, and an increase in sperm DNA fragmentation and teratozoospermia compared with non-smokers (p<0.05). There was also a reduction in the serum and seminal zinc level as well as an impairment in metabolic health in smokers compared with non-smokers (p<0.05). No significant differences between smokers and non-smokers were found for serum levels of LH, FSH, inhibin B, testosterone and estradiol. In the second part of our study, the most numerous ethnic groups of Slavs (n=654), Buryats (n=191), and Yakuts (n=125) were selected from the entire study population. Among three ethnic groups, the smoking intensity was higher in Slavs than in Buryats or Yakuts suggesting a greater tobacco addiction in Slavs than in Asians. A decrease in semen parameters and seminal zinc levels, and an increase in sperm DNA fragmentation and teratozoospermia was observed only in smoking Slavs (p<0.05); moderate decrease in testosterone and increase in triglyceride levels were revealed in smoking Yakuts (p<0.05), but no significant changes were detected in smoking Buryats.ConclusionWe concluded that cigarette smoking has an ethno-specific effect on male reproductive function, probably due to the different activity of the seminal antioxidant system, which is yet to be elucidated.

Cold exposure impacts DNA methylation patterns in cattle sperm

“…Relation between sperm methylome and fertility has been revealed in human by comparing the methylation profiles between fertile and infertile male sperm ( Laqqan et al, 2017 ; Oluwayiose et al, 2021 ). In human sperm, several external factors like smoking, alcohol, drug, obesity and stress can induce differential methylation of genes that activates post-fertilization and are critical for early embryonic development ( Keyhan et al, 2021 ; Osadchuk et al, 2023 ). Similar to human studies, a comparison between sperm of fertile and subfertile bulls identified several DMRs that overlapped with genes involved in the capacitation of sperm, establishment of pregnancy, maintenance of chromatin structure, development of blastocysts, placental development and nervous system development, suggesting sperm methylation as a biomarker of bull fertility ( Takeda et al, 2021 ; Tanaka et al, 2018 ; Capra et al, 2019 ; Luján et al, 2019 ; Costes et al, 2022 ; Llavanera et al, 2022 ; Stiavnicka et al, 2022 ).…”

Associations between tobacco inhalation and semen parameters in men with primary and secondary infertility: a cross-sectional study

“…The study delineated two primary groups based on smoking behavior: smokers (who were further divided into moderate smokers, consuming 1-10 cigarettes per day ( 11 ), and heavy smokers, consuming more than 10 cigarettes per day ( 12 )) and nonsmokers (nonsmokers included quitters and never-smokers). This classification was pivotal in examining the potential gradations in semen quality across different levels of tobacco exposure among the infertile male population.…”

6. Ảnh Hưởng Thói Quen Sinh Hoạt Tới Tinh Dịch Đồ Và Hormon Sinh Sản Của Nam Giới Khám Tại Phòng Khám Nam Học - Bệnh Viện Phụ Sản Hà Nội

“…Hút thuốc lá và sử dụng đồ uống có cồn đã được chứng minh là những yếu tố nguy cơ có mức độ ảnh hưởng tiêu cực tới sức khỏe toàn cầu [7,8] cũng như ảnh hưởng tới khả năng sinh sản của nam giới [9,10]. Một số nghiên cứu đã chỉ ra những người nghiện thuốc lá nặng có đặc điểm là giảm thể tích tinh dịch, giảm tổng số và nồng độ tinh trùng và giảm khả năng di chuyển của tinh trùng, đồng thời làm tăng sự phân mảnh DNA tinh trùng và quái thai so với những người không hút thuốc [9,10]. Một nghiên cứu phân tích gộp trên 5865 nam giới cũng chỉ ra hút thuốc lá ảnh hưởng toàn diện tới các chỉ số của tinh dịch đồ [11].…”