Longitudinal study of tryptophan degradation during and after pregnancy

Tryptophan pathway alterations in the postpartum period and in acute postpartum psychosis and depression

“…Our study confirms the earlier reports of physiological postpartum reductions in tryptophan levels and increased tryptophan metabolism to kynurenine (Abou-Saleh et al, 1999;Handley et al, 1977;Maes et al, 2002;Schrocksnadel et al, 1996;Schrocksnadel et al, 2003). However, our findings do not support the idea of an increased tryptophan metabolism as an etiological mechanism for severe postpartum mood disorders (Kohl et al, 2005;Maes et al, 2002).…”

“…During pregnancy, tryptophan metabolism is altered, with a decrease in total tryptophan and a shift in the proportions of free and bound tryptophan (Badaway, 2014). After pregnancy, both free and bound tryptophan levels gradually return to pre-pregnancy levels (Handley et al, 1977;Schrocksnadel et al, 1996;Schrocksnadel et al, 2003). The downstream tryptophan pathway beyond the degradation to kynurenine has never been investigated in women with severe postpartum mood disorders, but there is evidence for major alterations in severe mood disorders outside the postpartum period (Myint et al, 2007a;Myint et al, 2007b;Ogawa et al, 2014;Savitz et al, 2015a;Savitz et al, 2015b).…”

Immune modulation by mesenchymal stem cells

“…Foremost among the mediators of such effects are IL-10 [92,93], TGF-β [94], HGF [95], PGE 2 [96], and IDO [97]. The tryptophan concentration in maternal circulation falls steadily during pregnancy [98,99]. The fact that human MSCs can be isolated from several fetal tissues, as well as the placenta, amniotic fluid [100], fetal blood [4], and term umbilical cord blood [101] strengthen the theory that MSCs may have a role in fetal acceptance.…”

Sex Differences in the Regulation of Serotonergic Transmission and Behavior in 5-HT Receptor Knockout Mice

“…For example, even though plasma tryptophan concentration decreases progressively during pregnancy and ordinarily recovers normal values after delivery, a reduction of plasma tryptophan levels during the post-partum period has been suggested to contribute to the onset of symptoms of postpartum depression in some women (Handley et al, 1980;Maes et al, 2002;Schrocksnadel et al, 2003). Supporting this hypothesis, normal healthy women experienced a marked decrease in several parameters of mood following tryptophan depletion, whereas men did not (Ellenbogen et al, 1996).…”