Maternal n-3 Polyunsaturated Fatty Acid Enriched Diet Commands Fatty Acid Composition in Postnatal Brain and Protects from Neonatal Arterial Focal Stroke

Abstract

The fetus is strongly dependent on nutrients from the mother, including polyunsaturated fatty acids (PUFA). In adult animals, n-3 PUFA ameliorates stroke-mediated brain injury, but the modulatory effects of different PUFA content in maternal diet on focal arterial stroke in neonates are unknown. This study explored effects of maternal n-3 or n-6 enriched PUFA diets on neonatal stroke outcomes. Pregnant mice were assigned three isocaloric diets until offspring reached postnatal day (P) 10–13: standard, long-chain n-3 PUFA (n-3) or n-6 PUFA (n-6) enriched. Fatty acid profiles in plasma and brain of mothers and pups were determined by gas chromatography–mass spectrometry and cytokines/chemokines by multiplex protein analysis. Transient middle cerebral artery occlusion (tMCAO) was induced in P9-10 pups and cytokine and chemokine accumulation, caspase-3 and calpain-dependent spectrin cleavage and brain infarct volume were analyzed. The n-3 diet uniquely altered brain lipid profile in naïve pups. In contrast, cytokine and chemokine levels did not differ between n-3 and n-6 diet in naïve pups. tMCAO triggered accumulation of inflammatory cytokines and caspase-3-dependent and -independent cell death in ischemic-reperfused regions in pups regardless of diet, but magnitude of neuroinflammation and caspase-3 activation were attenuated in pups on n-3 diet, leading to protection against neonatal stroke. In conclusion, maternal/postnatal n-3 enriched diet markedly rearranges neonatal brain lipid composition and modulates the response to ischemia. While standard diet is sufficient to maintain low levels of inflammatory cytokines and chemokines under physiological conditions, n-3 PUFA enriched diet, but not standard diet, attenuates increases of inflammatory cytokines and chemokines in ischemic-reperfused regions and protects from neonatal stroke. Graphic Abstract

Maternal n-3 enriched diet reprograms neurovascular transcriptome and blunts inflammation in neonate

“…4A, lower panel). As we have previously reported, most brain cytokines and chemokines levels were lower in n-3 and n-6 diet pups at P10 (24 h) compared to standard diet (Chumak et al, 2022).…”

“…Breeding cages were randomly assigned to one of the experimental isocaloric diets (AIN-93G, BioServ): standard (Stand, BioServ #S7628), n-3 long chain (LC)-PUFA enriched (n-3, BioServ #S7630; soybean oil replaced with Menhaden Fish oil) or n-6 LC-PUFA supplemented (n-6, BioServ #S7629; based on corn oil). The detailed composition of the diets is presented in our previous publication (Chumak et al, 2022). The day of birth was defined as postnatal day (P) 0.…”

“…Cytokine/chemokine levels were measured using Bio-Plex Pro Mouse Cytokine Standard 31-Plex kit (Cat# 12,009,159, BioRad) on a Bio-Plex 200 analyser as per the manufacturer's guidelines. The baseline cytokine data has previously been published (Chumak et al, 2022).…”

“…Modulatory effects of n-3 PUFAs on immune function of various immune cells such as macrophages or microglia have been studied (Gutierrez, Svahn, & Johansson, 2019). We previously demonstrated that diet enriched in n-3 PUFA transforms brain lipid composition in the offspring and protects the neonatal brain from stroke, in part by blunting injurious immune responses (Chumak et al, 2022). However, how PUFAs affect the functions of brain endothelial cells in response to an inflammatory stimulus in the neonatal period is unknown.…”

Immune-Neurovascular Interactions in Experimental Perinatal and Childhood Arterial Ischemic Stroke

“…110 We showed that n3-PUFA enriched diet during gestation and postnatal period markedly changes lipid composition in brains of neonatal mice under physiological conditions and, interestingly, while it does not affect brain cytokine/chemokine levels under physiological conditions, n3-PUFA enriched diet mutes neuroinflammation and protects neonatal brain from stroke. 111 While the beneficial effects of lipid composition in protecting from acute injury in PAIS model are clear, the relative interplay of immune cells with dietary modifications during development and injury is not well understood.…”