Caffeine improves mitochondrial dysfunction in the white matter of neonatal rats with hypoxia-ischemia through deacetylation: a proteomic analysis of lysine acetylation

Aims

White matter damage (WMD) is linked to both cerebral palsy and cognitive deficits in infants born prematurely. The focus of this study was to examine how caffeine influences the acetylation of proteins within the neonatal white matter and to evaluate its effectiveness in treating white matter damage caused by hypoxia-ischemia.

Main methods

We employed a method combining affinity enrichment with advanced liquid chromatography and mass spectrometry to profile acetylation in proteins from the white matter of neonatal rats grouped into control (Sham), hypoxic-ischemic (HI), and caffeine-treated (Caffeine) groups.

Key findings

Our findings included 1,999 sites of lysine acetylation across 1,123 proteins, with quantifiable changes noted in 1,342 sites within 689 proteins. Analysis of these patterns identified recurring sequences adjacent to the acetylation sites, notably YKacN, FkacN, and G * * * GkacS. Investigation into the biological roles of these proteins through Gene Ontology analysis indicated their involvement in a variety of cellular processes, predominantly within mitochondrial locations. Further analysis indicated that the acetylation of tau (Mapt), a protein associated with microtubules, was elevated in the HI condition; however, caffeine treatment appeared to mitigate this over-modification, thus potentially aiding in reducing oxidative stress, inflammation in the nervous system, and improving mitochondrial health. Caffeine inhibited acetylated Mapt through sirtuin 2 (SITR2), promoted Mapt nuclear translocation, and improved mitochondrial dysfunction, which was subsequently weakened by the SIRT2 inhibitor, AK-7.

Significance

Caffeine-induced changes in lysine acetylation may play a key role in improving mitochondrial dysfunction and inhibiting oxidative stress and neuroinflammation.

Assisted reproductive techniques do not impact late neurodevelopmental outcomes of preterm children

Objective

Assisted reproductive technology (ART) increases the rate of preterm births, though few studies have analyzed outcomes for these infants. No data are available on 4-year-old children born prematurely after ART. The objective was to investigate whether ART affect the neurodevelopmental outcomes at 4 years in preterm infants born before 34 weeks of gestational age (GA).

Methods and results

A total of 166 ART and 679 naturally conceived preterm infants born before 34 weeks GA between 2013 and 2015 enrolled in the Loire Infant Follow-up Team were included. Neurodevelopment was assessed at 4 years using the age and stage questionnaire (ASQ) and the need for therapy services. The association between the socio-economic and perinatal characteristics and non-optimal neurodevelopment at 4 years was estimated. After adjustment, the ART preterm group remained significantly associated with a lower risk of having at least two domains in difficulty at ASQ: adjusted odds ratio (aOR) 0.34, 95% confidence interval (CI) (0.13-0.88), p = 0.027. The factors independently associated with non-optimal neurodevelopment at 4 years were male gender, low socio-economic level, and 25-30 weeks of GA at birth. The need for therapy services was similar between groups (p = 0.079). The long-term neurodevelopmental outcomes of preterm children born after ART are very similar, or even better than that of the spontaneously conceived children.

Neurodevelopment at 5 years of age for preterm-born children according to mode of conception: a cohort study

BACKGROUND

Preterm delivery is a risk factor for sub-optimal neurodevelopment. Pregnancies conceived after medically-assisted reproduction - which includes in vitro fertilisation, with or without intracytoplasmic insemination, as well as induction of ovulation followed by intra-uterine insemination or timed intercourse - have a higher risk of preterm delivery. Few studies have evaluated the outcome at more than 2 years of age of such preterm-born children.

OBJECTIVE

To evaluate neurodevelopmental outcome at 5 ½ years of age of children born preterm according to the mode of conception (spontaneous versus medically-assisted reproduction).

STUDY DESIGN

4349 children born between 24 and 34 weeks of gestation who survived to 5 ½ years of age in the 2011 French prospective national cohort study EPIPAGE-2 were included: 814 in the medically-assisted reproduction group (433 by in vitro fertilisation, with or without intracytoplasmic insemination, and 381 by induction of ovulation) and 3535 in the spontaneously conceived group. Neurodevelopmental outcomes studied were sensory (hearing and vision) impairments, cerebral palsy, cognition and developmental coordination disorders. Multivariate analyses were performed with generalised estimating equation models adjusted for gestational age, antenatal steroids and social characteristics. All analyses were performed following multiple imputation. Sensitivity analyses were performed with the populations of singletons and cases with complete data.

RESULTS

No differences in cerebral palsy (adjusted odds ratio =1.00, 95% confidence interval 0.67-1.49), neurodevelopmental impairment (adjusted odds ratio=1.09; 95% confidence interval 0.82-1.45), or developmental coordination disorders (adjusted odds ratio=0.75; 95% confidence interval 0.50-1.12) were found between children born following medically-assisted reproduction and children born following spontaneous conception after adjustment for sociodemographic factors. For proportions of children with an intelligence quotient below one and two standard deviations, there were no differences between those born after medically-assisted reproduction or spontaneous pregnancy (respectively, adjusted odds ratio= 0.99 95% confidence interval 0.80-1.23, and adjusted odds ratio=1.14; 95% confidence interval 0.83-1.56). In subgroup analyses, no differences were seen between children born following induction of ovulation nor among those conceived through in vitro fertilisation when compared to children conceived spontaneously. Sensitivity analyses were consistent with the main results.

CONCLUSION

In this cohort of preterm born children, there was no evidence of an impact of the mode of conception on neurodevelopmental outcomes at 5 ½ years of age.

Neurodevelopmental outcomes of preterm infants conceived by assisted reproductive technology

BACKGROUND

There have been concerns about the development of children conceived through assisted reproductive technology. Despite multiple studies investigating the outcomes of assisted conception, data focusing specifically on the neurodevelopmental outcomes of infants conceived through assisted reproductive technology and born preterm are limited.

OBJECTIVE

This study aimed to evaluate and compare the neurodevelopmental outcomes of preterm infants born at <29 weeks' gestation at 18 to 24 months' corrected age who were conceived through assisted reproductive technology and those who were conceived naturally.

STUDY DESIGN

This retrospective cohort study included inborn, nonanomalous infants, born at <29 weeks' gestation between January 1, 2010, and December 31, 2016, who had a neurodevelopmental assessment at 18 to 24 months' corrected age at any of the 10 Canadian Neonatal Follow-Up Network clinics. The primary outcome was neurodevelopmental impairment at 18 to 24 months, defined as the presence of any of the following: cerebral palsy; Bayley-III cognitive, motor, or language composite score of <85; sensorineural or mixed hearing loss; and unilateral or bilateral visual impairment. Secondary outcomes included mortality, composite of mortality or neurodevelopmental impairment, significant neurodevelopmental impairment, and each component of the primary outcome. We compared outcomes between infants conceived through assisted reproductive technology and those conceived naturally, using bivariate and multivariable analyses after adjustment.

RESULTS

Of the 4863 eligible neonates, 651 (13.4%) were conceived using assisted reproductive technology. Maternal age; education level; and rates of diabetes mellitus, receipt of antenatal corticosteroids, and cesarean delivery were higher in the assisted reproduction group than the natural conception group. Neonatal morbidity and death rates were similar except for intraventricular hemorrhage, which was lower in the assisted reproduction group (33% [181 of 546] vs 39% [1284 of 3318]; P=.01). Of the 4176 surviving infants, 3386 (81%) had a follow-up outcome at 18 to 24 months' corrected age. Multivariable logistic regression adjusting for gestational age, antenatal steroids, sex, small for gestational age, multiple gestations, mode of delivery, maternal age, maternal education, pregnancy-induced hypertension, maternal diabetes mellitus, and smoking showed that infants conceived through assisted reproduction was associated with lower odds of neurodevelopmental impairment (adjusted odds ratio, 0.67; 95% confidence interval, 0.52-0.86) and the composite of death or neurodevelopmental impairment (adjusted odds ratio, 0.67; 95% confidence interval, 0.54-0.84). Conception through assisted reproductive technology was associated with decreased odds of a Bayley-III composite cognitive score of <85 (adjusted odds ratio, 0.68; 95% confidence interval, 0.48-0.99) and composite language score of <85 (adjusted odds ratio, 0.67; 95% confidence interval, 0.50-0.88).

CONCLUSION

Compared with natural conception, assisted conception was associated with lower odds of adverse neurodevelopmental outcomes, especially cognitive and language outcomes, at 18 to 24 months' corrected age among preterm infants born at <29 weeks' gestation. Long-term follow-up studies are required to assess the risks of learning disabilities and development of complex visual-spatial and processing skills in these children as they reach school age.