Telomerase activity in pregnancy complications (Review)

Abstract

Telomeres are specific DNA regions positioned at the ends of chromosomes and composed of functional non-coding repeats. Upon cell division, the telomeres decrease in length by a preordained amount. When the telomeres become critically short, cells lose the ability to divide and enter a specific functioning mode designated as 'cellular senescence'. However, human tissues express an enzyme that deters the shrinking of the telomeres, the telomerase. Due to its ability to maintain telomere length, the telomerase slows down and possibly suspends the aging of the cells. In regard to this, solid evidence demonstrates that female human fertility decreases with increased maternal age and that various adverse factors, including alterations in telomerase activity, can contribute to age-associated infertility in women. The fact that telomerase activity is regulated in a time- and location-dependent manner in both embryo and placental tissues, highlights it potential importance to the successful completion of pregnancy. Since maternal age is a crucial determining factor for the success of in vitro and in vivo fertilization, numerous studies have focused on telomerase activity and its correlation with mammalian fertilization, as well as the following cleavage and pre-implantation developmental processes. Associations between telomerase activity and pregnancy complications have been previously observed. Our aim in this review was to summarize and critically discuss evidence correlating telomerase activity with pregnancy complications.

Gravidity is not associated with telomere length in a biracial cohort of middle-aged women: The Coronary Artery Risk Development in Young Adults (CARDIA) study

“…We used multiple linear regression to test for associations between gravidity and telomere length (adjusted for age and race). Because the groups had different years of education and proportions of women with gestational diabetes and preterm births and all these factors have been associated with telomere length in earlier investigations [ 15 , 16 , 18 ], we performed an ANCOVA to determine whether years of education, preterm birth, or gestational diabetes affected the association of telomere length and gravidity group. A chi-square test was performed to determine whether there was a difference in prevalence of high-risk, short telomere length, defined as the lowest quartile of telomere length (≤ 0.844) between groups.…”

“…We repeated all analyses stratified by race, as race has been shown to influence telomere length in women [ 18 ]. We also tested whether women with gestational diabetes or preterm birth had shorter telomeres than women without these complications in our sample because telomerase activity has been shown to be acutely affected by complications of pregnancy [ 15 ]. Next, we conducted two sensitivity analyses.…”

“…Short telomere length (≤25 th percentile) has been associated with multiple biological and behavioral risk factors for atherosclerotic cardiovascular disease [ 12 – 14 ]; we also hypothesized that women who have had 2–3 pregnancies would be less likely to have short telomere lengths, defined as ≤ 25 th percentile, compared to women with <2 or ≥4 pregnancies. Telomere length and telomerase activity can be acutely altered during pregnancy in certain pregnancy-related conditions [ 15 , 16 ], so we also tested for differences in telomere length in women with and without gestational diabetes and preterm birth.…”

Telomere length and telomerase activity in osteoporosis and osteoarthritis (Review)

“…TL and telomerase activity are strongly associated with human health as they have been linked to several age-related diseases, such as cancer, cardiovascular disease (CAD), diabetes, rheumatoid arthritis and psychiatric disorders (34)(35)(36)(37)(38). Moreover, previous studies have suggested that female human fertility decreases with an increased maternal age and that various adverse factors, including reduced telomerase activity, can contribute to age-associated infertility in women (39,40). Furthermore, Vakonaki et al recently demonstrated the existence of a link between TL and drug abuse, which ultimately results in premature biological aging (41).…”

Telomere reprogramming during fetal life in low socioeconomic mothers

“…The adverse intrauterine environment during pregnancy is caused by factors like psychosocial risk issues, lack of social support, low socioeconomic status, and childhood trauma [19,20]. Association to the telomere and fetal programming and gene expression modifications has also been found linked with pre-eclampsia [21], intrauterine growth restriction (IUGR) [22], oxidative and nitrosative stress, and hypoxia [23,24].…”