Maternal depression negatively affects the neurodevelopment of offspring, but its pharmacological treatment during gestation remains controversial. This study reports the consequences of maternal depression and/or prenatal antidepressant treatment with mirtazapine on offspring early neurodevelopment via an animal model of maternal depression induced by pregestational chronic unpredictable stress (CUS). Offspring from four groups were studied: nonstressed vehicle-treated dams, nonstressed mirtazapine-treated dams, stressed vehicle-treated dams, and stressed mirtazapine-treated dams. The hippocampal excitability of offspring was examined in primary hippocampal cultures established on the first postnatal day, reflecting mostly prenatal development, and in hippocampal slices prepared on postnatal days 11–13, reflecting an early postnatal development. The pregestational CUS modeling of maternal depression moderately suppressed offspring hippocampal excitability in primary cultures but facilitated it in slices. Mirtazapine administered to CUS-exposed dams partly rectified the changes observed in primary cultures of pups from untreated dams and, more prominently, in slices. Mirtazapine itself negatively affected the hippocampal excitability of nonstressed dam offspring in primary culture, and this effect was diminished in slices. Since altered hippocampal neurotransmission might be responsible, at least in part, for the neuropsychopathologies frequently observed in the offspring of depressed mothers, and mirtazapine was able to partly relieve such changes, this treatment may be also beneficial during the prenatal and perinatal periods.

Elevated plasma homocysteine (Hcy) levels lead to hyperhomocysteinemia, a condition associated with various neurological disorders affecting multiple brain regions, including the hippocampus. In this study, we investigated the effects of exposing cultured rat hippocampal neurons to Hcy concentrations corresponding to mild, moderate, and severe hyperhomocysteinemia. A short 24-hour exposure had minimal effects, whereas prolonged exposure up to 14 days moderately enhanced hippocampal excitability without altering the gene expression of voltage-dependent calcium, sodium, or potassium channels or intracellular calcium levels. These findings suggest that Hcy-induced changes in neuronal excitability may contribute to neuropathologies associated with hyperhomocysteinemia.

Homocysteine is a non-proteinogenic amino acid formed during the metabolism of methionine to cysteine and plays a critical role in maintaining cellular homeostasis. Although multiple enzymatic pathways tightly regulate homocysteine levels, their dysfunction can lead to elevated circulating homocysteine, which is recognized as a risk factor for various cardiovascular and neurological disorders. While most evidence linking homocysteine to specific pathologies comes from observational studies, emerging data suggest that dysregulation of ion channels may be an important underlying mechanism. In this review, we summarize the effects of homocysteine on the expression and function of key ion channel families including calcium, sodium, and potassium channels, and discuss their potential pathophysiological implications.

Maternal depression negatively affects the neurodevelopment of offspring, but its pharmacological treatment during gestation remains controversial. This study reports the consequences of maternal depression and/or prenatal antidepressant treatment with mirtazapine on offspring early neurodevelopment via an animal model of maternal depression induced by pregestational chronic unpredictable stress (CUS). Offspring from four groups were studied: nonstressed vehicle-treated dams, nonstressed mirtazapine-treated dams, stressed vehicle-treated dams, and stressed mirtazapine-treated dams. The hippocampal excitability of offspring was examined in primary hippocampal cultures established on the first postnatal day, reflecting mostly prenatal development, and in hippocampal slices prepared on postnatal days 11-13 reflecting an early postnatal development. Pregestational CUS modeling of maternal depression moderately suppressed offspring hippocampal excitability in primary cultures but facilitated it in slices. Mirtazapine administered to CUS-exposed dams partly rectified the changes observed in primary cultures of pups from untreated dams and, more prominently, in slices. Mirtazapine itself negatively affected the hippocampal excitability of nonstressed dam offspring in primary culture, and this effect was diminished in slices. Since altered hippocampal neurotransmission might be responsible, at least in part, for the neuropsychopathologies frequently observed in the offspring of depressed mothers, and mirtazapine was able partly relieve such changes, this treatment may be also beneficial during the prenatal and perinatal periods.