Gender-Dependent Effect of Maternal Methyl-Enriched Diet on the Expression of Genetic Absence Epilepsy and Comorbid Depression in Adult Offspring of WAG/Rij Rats

Maternal Methyl-Enriched Diet Increases DNMT1, HCN1, and TH Gene Expression and Suppresses Absence Seizures and Comorbid Depression in Offspring of WAG/Rij Rats

The reduced expression of the HCN1 ion channel in the somatosensory cortex (SSC) and mesolimbic dopamine deficiency are thought to be associated with the genesis of spike-wave discharges (SWDs) and comorbid depression in the WAG/Rij rat model of absence epilepsy. This study aimed to investigate whether the maternal methyl-enriched diet (MED), which affects DNA methylation, can alter DNMT1, HCN1, and TH gene expression and modify absence seizures and comorbid depression in WAG/Rij offspring. WAG/Rij mothers were fed MED (choline, betaine, folic acid, vitamin B12, L-methionine, zinc) or a control diet for a week before mating, during pregnancy, and for a week after parturition. MED caused sustained suppression of SWDs and symptoms of comorbid depression in the offspring. Disease-modifying effects of MED were associated with increased expression of the DNMT1 and HCN1 genes in the SSC and hippocampus, as well as DNMT1, HCN1, and TH genes in the nucleus accumbens. No changes in gene expression were detected in the hypothalamus. The results indicate that maternal MED can suppress the genetic absence epilepsy and comorbid depression in offspring. Increased expression of the DNMT1, HCN1, and TH genes is suggested to be a molecular mechanism of this beneficial phenotypic effect.

The impact of early-life environment on absence epilepsy and neuropsychiatric comorbidities

This review discusses the long-term effects of early-life environment on epileptogenesis, epilepsy, and neuropsychiatric comorbidities with an emphasis on the absence epilepsy. The WAG/Rij rat strain is a well-validated genetic model of absence epilepsy with mild depression-like (dysthymia) comorbidity. Although pathologic phenotype in WAG/Rij rats is genetically determined, convincing evidence presented in this review suggests that the absence epilepsy and depression-like comorbidity in WAG/Rij rats may be governed by early-life events, such as prenatal drug exposure, early-life stress, neonatal maternal separation, neonatal handling, maternal care, environmental enrichment, neonatal sensory impairments, neonatal tactile stimulation, and maternal diet. The data, as presented here, indicate that some early environmental events can promote and accelerate the development of absence seizures and their neuropsychiatric comorbidities, while others may exert anti-epileptogenic and disease-modifying effects. The early environment can lead to phenotypic alterations in offspring due to epigenetic modifications of gene expression, which may have maladaptive consequences or represent a therapeutic value. Targeting DNA methylation with a maternal methyl-enriched diet during the perinatal period appears to be a new preventive epigenetic anti-absence therapy. A number of caveats related to the maternal methyl-enriched diet and prospects for future research are discussed.

Circulating choline pathway nutrients and depression after ischemic stroke

BACKGROUND AND PURPOSE

Choline pathway nutrients, including choline and betaine, are reported to exert antidepressant effects. However, there is little population-based evidence on the relationships between circulating choline and betaine and poststroke depression (PSD). We aimed to prospectively explore the associations between plasma choline and betaine and depression after ischemic stroke.

METHODS

This study was based on the China Antihypertensive Trial in Acute Ischemic Stroke. A total of 612 participants with plasma choline and betaine concentrations were included in the analysis. The study outcome was depression 3 months after ischemic stroke. Logistic regression models were performed to estimate the relationships between plasma choline and betaine and the risk of PSD. Risk reclassification and calibration of models with choline or betaine were analyzed.

RESULTS

Patients with PSD had lower choline and betaine levels than those without PSD (p < 0.05). Compared with tertile 1, the multivariable-adjusted odds ratios (95% CIs) for tertile 3 of choline and betaine were 0.54 (0.35-0.83) and 0.59 (0.38-0.92), respectively. Per 1 SD increase in choline or betaine was associated with a 25% (95% CI 9%-37%) or an 19% (95% CI 3%-32%) decreased risk of PSD, respectively. Furthermore, the addition of choline or betaine to the established risk factors model improved the risk reclassification for PSD, as shown by an increase in the net reclassification index and integrated discrimination improvement (all p < 0.05).

CONCLUSIONS

Patients with elevated levels of choline and betaine had a lower risk of depression after acute ischemic stroke, suggesting the protective significance of choline pathway nutrients for PSD.