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Nishio, N.

Publications and source records attributed to Nishio, N..

4 recordsLinked to original sources

A high fat containing chicken egg-only diet suppresses fatty liver induced by a lipid-rich methionine and choline deficient diet.

Nonalcoholic fatty liver disease (NAFLD) is a simple hepatic steatosis, which may proceed to nonalcoholic steatohepatitis (NASH) in the presence of steatosis and inflammation with hepatocyte injury. Obesity induced by a high-fat diet or high monosaccharide diet is considered a risk factor for NAFLD. A popular mouse model of NAFLD is a high-fat diet consisting of 60% energy from fat. A modified methionine and choline deficient (MCD) diet containing 60% energy from fat (CDAHFD) is a quick induction model for NAFLD. Chicken eggs also contain 60% energy from fat with very low carbohydrate. Here we compared liver pathologies in mice fed either a CDAHFD or egg-only diet. We found that a CDAHFD induced NAFLD within only two weeks.Ballooning of hepatocytes with an of immune cell appearance in the liver and high serum ALT and AST indicated that the mice fed CDAHFD developed NAFLD, which could proceed to NASH. However, mice fed an egg-only diet did not develop NAFLD even after 7 weeks. These mice showed normal liver histology with normal ALT and AST. The mice fed an egg-only diet showed high blood ketone bodies and normal blood glucose. Furthermore we found that the mice fed a combination CDAHFD /egg diet or mice fed an egg-only diet after two weeks of CDAHFD diet showed almost normal ALT and AST with reduced levels of fat bodies in the liver. These results indicate that an egg-only diet strongly inhibits high fat and carbohydrates induced NAFLD.Competing Interest StatementThe authors have declared no competing interest.View Full Text

pathology↗

Are mice born normally with an egg-only diet?

Chicken eggs (egg) contain high amounts of important proteins and fat with a very low amount of carbohydrates, and also contain all vitamins and minerals needed for the chick to develop. We mated 8-week-old mice consuming an egg-only diet, and examined whether mice got pregnant and mice gave birth. Then we continued to raise newborn mice only consuming an egg-only diet compared to normal chew diet. We found that the rate of pregnancy of the mice consuming an egg-only diet was not different from that of the mice consuming normal chew diet. Further, we found that the number of pupus born from the mother consuming only eggs was not different from that of the mother consuming normal chew diet. However, the newborn mice from the mother fed only eggs did not grow healthy when they consume egg-only diet. Only few mice were alive at one month after birth. Then we change the diet just before or just after birth from egg only diet to normal chew diet and we found that both group grew healthy more than one month. These results indicate that mice are born healthy only with egg only diet.

developmental biology↗

Reciprocal connectivity between secondary auditory cortical field and amygdala in mice

Recent studies have examined the feedback pathway from the amygdala to the auditory cortex in conjunction with the feedforward pathway from the auditory cortex to the amygdala. However, these connections have not been fully characterized. Here, to visualize the comprehensive connectivity between the auditory cortex and amygdala, we injected cholera toxin subunit b (CTB), a bidirectional tracer, into multiple subfields in the mouse auditory cortex after identifying the location of these subfields using flavoprotein fluorescence imaging. After injecting CTB into the secondary auditory field (A2), we found densely innervated CTB-positive axon terminals that were mainly located in the lateral amygdala (La), and slight innervations in other divisions such as the basal amygdala. Moreover, we found a large number of retrogradely-stained CTB-positive neurons in La after injecting CTB into A2. When injecting CTB into the primary auditory cortex (A1), a small number of CTB-positive neurons and axons were visualized in the amygdala. Finally, we found a near complete absence of connections between the other auditory cortical fields and the amygdala. These data suggest that reciprocal connections between A2 and La are main conduits for communication between the auditory cortex and amygdala in mice.

neuroscience↗

Thalamocortical Projectional Divergence Leads to Complexity in Functional Organizations in Mouse Auditory Cortex

Frequency-related topological projections from the ventral division of the medial geniculate body (MGv) relay the tonotopic organization found in primary auditory cortex (A1). However, relaying circuits of the functional organization to higher-order, secondary auditory field (A2) have not been identified so far. Here, using tracing, we found that A2 receives dense topological projections from MGv in mice, and that tonotopy was established in A2 even when primary fields including A1 were removed. These indicate that thalamic inputs to A2 are sufficient for generating its tonotopy. Moreover, neuronal responses in the thalamocortical recipient layer of A2 showed wider bandwidth and greater heterogeneity of the best frequency distribution than those of A1, which was attributed to larger divergence of thalamocortical projections from MGv to A2 than those from MGv to A1. The current study identifies that the functional organization in the auditory cortex can be determined by the structure of thalamocortical input.\n\nSignificant StatementAlthough peripheral input patterns to the primary auditory cortex (A1) of the brain are well understood, how tonal information is relayed to higher-order regions such as the secondary auditory field (A2) remains unclear. This work revealed a new source of auditory information to A2; the tonal map in mouse A2 is primarily produced by orderly projections from the primary auditory thalamus. We also found that the complex behaviour and organization of neurons in A2 is generated by divergent projections from the primary thalamus that converge on neurons in A2. Our findings indicate that thalamocortical projections constitute a major factor that determines the regional properties and functional organization of mouse A2.

neuroscience↗