Viral regulation of aquaporin 4, connexin 43, microcephalin and nucleolin

Abstract

The current study investigated whether human influenza viral infection in midpregnancy leads to alterations in proteins involved in brain development. Human influenza viral infection was administered to E9 pregnant Balb/c mice. Brains of control and virally exposed littermates were subjected to microarray analysis, SDS-PAGE and western blotting at three postnatal stages. Microarray analysis of virally-exposed mouse brains showed significant, two-fold change in expression of multiple genes in both neocortex and cerebellum when compared to sham-infected controls. Levels of mRNA and protein levels of four selected genes were examined in brains of exposed mice. Nucleolin mRNA was significantly decreased in day 0 and day 35 neocortex and significantly increased in day 35 cerebellum. Protein levels were significantly upregulated at days 35 and 56 in neocortex and at day 56 in cerebellum. Connexin 43 protein levels were significantly decreased at day 56 in neocortex. Aquaporin 4 mRNA was significantly decreased in day 0 neocortex. Aquaporin 4 protein levels decreased in neocortex significantly at day 35. Finally, microcephalin mRNA was significantly decreased in day 56 neocortex and protein levels were significantly decreased at 56 cerebellum. These data suggest that influenza viral infection in midpregnancy in mice leads to long term changes in brain markers for enhanced ribosome genesis (nucleolin), increased production of immature neurons (microcephalin), and abnormal glial-neuronal communication (connexin 43 and aquaporin 4).

The effects of prenatal H1N1 infection at E16 on FMRP, glutamate, GABA, and reelin signaling systems in developing murine cerebellum

“…Cerebella were identified and dissected as previously described (Fatemi et al, 2008a,b,c, 2009a,b, 2012a) using coronal images from a stereotaxic mouse brain atlas (Franklin and Paxinos, 1997). The following coordinates were used: starting at −1.40 mm to −3.68 mm from interaural line and from −5.20 mm to −7.48 mm from bregma.…”

“…Brain tissue was prepared and SDS-PAGE and western blotting was carried out as previously described (Fatemi et al, 2008a,b,c, 2009a,b, 2011b). The blots were incubated overnight at 4°C with the primary antibodies listed in Table 1.…”

“…An important environmental risk factor for the development of brain dysfunctions relevant to these neurodevelopmental disorders is maternal infection during critical stages of pregnancy (Boksa, 2003; Brown, 2006; Brown and Susser, 2002; Fatemi, 2008; Fatemi et al, 2002a; Patterson, 2007). Our laboratory has demonstrated that infection of pregnant mice with a mouse-adapted human influenza virus [A/NWS/33 (H1N1)] on embryonic days 7 (E7), E9, E16, and E18 results in abnormal expression of brain genes, altered brain structure, neurochemical changes, and behavioral deficits in the offspring of exposed mice (Fatemi et al, 1999, 2002a, 2005a, 2008a,b,c, 2009a,b, 2012a; Shi et al, 2003; Winter et al, 2008). These results show concordance with some of the brain biochemical, structural, and behavioral indices observed in subjects with schizophrenia or autism (Fatemi, 2005a; Meyer et al, 2009, 2011; Palmen et al, 2004).…”

The Neurodevelopmental Hypothesis of Schizophrenia, Revisited

“…Aquaporin 4 is localized to astrocytes and ependymal cells in brain and is involved with water transport. 76,77 Aquaporin 4 protein expression is significantly decreased at postnatal day 35 in neocortex in BALB/c mice following infection at E9 78 possibly resulting in altered cell morphology. Similarly, chronic actin depolymerization may alter gene expression in schizophrenia (S.H.…”

Pre-clinical models of neurodevelopmental disorders: focus on the cerebellum

“…Fatemi laboratory has pioneered a mouse model of prenatal influenza infection following intranasal administration of live virus to pregnant mice at different time points across pregnancy (Meyer et al, 2009; Kneeland and Fatemi, 2013). In addition to a number of brain and behavioral abnormalities observed in offspring exposed in utero to influenza infection, Fatemi's group found maldevelopment of the cerebellum and significantly altered expression of several genes associated with schizophrenia or ASD (Sema3a, Trfr2 and Vldlr) and involved in abnormal glial-neuronal communication and neuron migration (connexin 43 and aquaporin 4) and myelination (Fatemi et al, 2008a,b; Fatemi et al, 2009). …”