Association of Parental Age and the Type of Down Syndrome on the Territory of Bosnia and Herzegovina

The role of the mitochondrial trans-sulfuration in cerebro-cardio renal dysfunction during trisomy down syndrome

One in 700 children is born with the down syndrome (DS). In DS, there is an extra copy of X chromosome 21 (trisomy). Interestingly, the chromosome 21 also contains an extra copy of the cystathionine beta synthase (CBS) gene. The CBS activity is known to contribute in mitochondrial sulfur metabolism via trans-sulfuration pathway. We hypothesize that due to an extra copy of the CBS gene there is hyper trans-sulfuration in DS. We believe that understanding the mechanism of hyper trans-sulfuration during DS will be important in improving the quality of DS patients and towards developing new treatment strategies. We know that folic acid "1-carbon" metabolism (FOCM) cycle transfers the "1-carbon" methyl group to DNA (H3K4) via conversion of s-adenosyl methionine (SAM) to s-adenosyl homocysteine (SAH) by DNMTs (the gene writers). The demethylation reaction is carried out by ten-eleven translocation methylcytosine dioxygenases (TETs; the gene erasers) through epigenetics thus turning the genes off/on and opening the chromatin by altering the acetylation/HDAC ratio. The S-adenosyl homocysteine hydrolase (SAHH) hydrolyzes SAH to homocysteine (Hcy) and adenosine. The Hcy is converted to cystathionine, cysteine and hydrogen sulfide (H2S) via CBS/cystathioneγ lyase (CSE)/3-mercaptopyruvate sulfurtransferase (3MST) pathways. Adenosine by deaminase is converted to inosine and then to uric acid. All these molecules remain high in DS patients. H2S is a potent inhibitor of mitochondrial complexes I-IV, and regulated by UCP1. Therefore, decreased UCP1 levels and ATP production can ensue in DS subjects. Interestingly, children born with DS show elevated levels of CBS/CSE/3MST/Superoxide dismutase (SOD)/cystathionine/cysteine/H2S. We opine that increased levels of epigenetic gene writers (DNMTs) and decreased in gene erasers (TETs) activity cause folic acid exhaustion, leading to an increase in trans-sulphuration by CBS/CSE/3MST/SOD pathways. Thus, it is important to determine whether SIRT3 (inhibitor of HDAC3) can decrease the trans-sulfuration activity in DS patients. Since there is an increase in H3K4 and HDAC3 via epigenetics in DS, we propose that sirtuin-3 (Sirt3) may decrease H3K4 and HDAC3 and hence may be able to decrease the trans-sulfuration in DS. It would be worth to determine whether the lactobacillus, a folic acid producing probiotic, mitigates hyper-trans-sulphuration pathway in DS subjects. Further, as we know that in DS patients the folic acid is exhausted due to increase in CBS, Hcy and re-methylation. In this context, we suggest that folic acid producing probiotics such as lactobacillus might be able to improve re-methylation process and hence may help decrease the trans-sulfuration pathway in the DS patients.

[Risk factors in the origin of Down syndrome]

Down syndrome (DS) is the most common autosomal aneuploidy and the leading cause of intellectual disability of genetic origin worldwide. It is identified as a syndrome in which the variability of its clinical manifestations and the severity of its phenotype have a multifactorial origin. Worldwide prevalence ranges between 1 per 700 live births and several factors that may be involved in the origin of DS have been proposed. Our objective was to describe updates regarding risk factors in the cytogenetic origin or cause of DS. We conducted a narrative review study in which a literature search was carried out from January to June 2022 in databases such as PubMed, EBSCO, Medigraphic, ClinicalKey, and meta-search engines such as Elsevier and Evidence Alerts. Only articles published in the last 10 years in English and Spanish were included. The search terms used were: Down syndrome, risk factors, prevention. Although DS is a very common chromosomal pathology worldwide, there is no single risk factor at the origin of meiotic or mitotic nondisjunction of chromosome 21, but rather each of the associated risk factors contributes to a greater or lesser degree to a cytogenetic predisposition in the etiology of trisomy 21. During the review it was identified that the main established risk factor associated with DS is still advanced maternal age (≥ 35 years).

Incidence of Down Syndrome by maternal age in Chinese population

Objective: This study aims to estimate the maternal age-related risk of Down syndrome in an Asian population.

Methods: We performed a retrospective data analysis including a total of 206,295 pregnant women who presented for second-trimester maternal serum screening for Down syndrome at Hubei Maternal and Child Health Hospital for the years 2008–2017. Cases were assigned to three groups: ≤26 years of age, 27–33 years of age, and ≥34 years of age. The incidence of Down Syndrome was calculated for each age group. The differences between groups were tested using the chi-square (χ2) test.

Results: The incidence of Down syndrome in women ≤26 years of age, 27–33 years of age, and ≥34 years of age was 0.67‰, 0.29‰, and 2.07‰ respectively. Statistically significant difference was found between the three age groups (χ2 = 79.748, p < 0.05).

Conclusion: Down syndrome rate was significantly higher in women ≥34 years of age. Younger women (≤26 years of age) had a significantly higher risk for Down’s syndrome, compared to women aged 27–33.

Association of Comorbid with Developmental Quotient in Down Syndrome Children

BACKGROUND: Down syndrome (DS) is the most common genetic disorder in children. Children with DS tend to have various comorbid due to developmental abnormalities of chromosome 21, such as congenital heart defects, hearing loss, otitis media, eye disorders, obstructive sleep apnea, thyroid hormone disorders, gastrointestinal atresia, hip joint dislocation, leukemia, and Hirschsprung’s disease. Moreover, they also show cognitive impairments in concentration, communication, memory, and the ability to carry out tasks. Caput Scale/Clinical Adaptive Test/Clinical Linguistic and Auditory Milestone Scale (CAT-CLAMS) is one of the developmental assessment instruments to screen for cognitive disorders. AIM: Hereby, we aimed to find the association of comorbid with developmental quotient in DS children. Data were obtained from medical record with sample age 0–18 years and suffering from DS. METHODS: This was observational analytic study with cross-sectional approach, conducted in DS children age 0–18 years who were treated in Sanglah Hospital in 2018. Characteristic data and comorbid were obtained from medical record, meanwhile, development status was assessed using Caput Scale/CAT-CLAMS. Chi-square was applied to determine the association between comorbidities and development quotient (DQ) in DS children. RESULTS: A total of 32 children with DS were treated in Sanglah Hospital during 2018 with median age was 2 years old and dominated by female patient (71.9%). Several comorbidities were found such as endocrine disorders in 27 children (84.3%), congenital heart disease (CHD) in 16 children (50%), and other comorbid including microcephaly, congenital cataract, palatoschizis, gastrointestinal defects, and congenital talipes equinovarus in 13 children (40.4%). The most common endocrine disorders was congenital hypothyroidism (81.25%), while the most common CHD was patent ductus arteriosus (25%). Bivariate Chi-square analysis showed significant association between comorbid and DQ (PR = 1.4 [95% CI 0.95–1.97], p = 0.03). CONCLUSION: We found an association between comorbidities and DQ in DS children.

Case report : Actinomyces naeslundii complicating preterm labour in a trisomy-21 pregnancy

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Actinomyces naeslundii causing preterm birth.

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Inappropriate antibiotics usage postpartum.

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Treatment of intrapartum Actinomyces naeslundii to prevent preterm birth.

Preterm birth is a global concern with considerable morbidity and mortality. Intrapartum infection is a known cause of preterm birth and Actinomyces infection is one of the infections contributing to preterm birth. We report a case of preterm birth of a trisomy-21 neonate to a mother with positive Actinomyces naeslundii from an intra-operative placental swab sample and discussed the relationship of this bacteria and preterm delivery, and the role of postpartum antibiotics use in this case.