Time-restricted feeding prevents high-fat and high-cholesterol diet-induced obesity but fails to ameliorate atherosclerosis in apolipoprotein E-knockout mice

One of the leading risk factors for atherosclerosis is obesity, which is commonly caused by a nutrient-rich Western-style diet, sedentary behaviors, and shift work. Time-restricted (TR) feeding and intermittent fasting are both known to prevent overweight and adiposity, improve glucose tolerance, and decrease plasma cholesterol in high-fat diet-induced obese mice. Here we examined the overall effects of TR feeding of a Western diet (fat, 40.5 Kcal%; cholesterol, 0.21 g%) using 8-week-old Apoe^−/− mice. Mice were assigned into three groups: (1) an ad libitum (AL) group fed an AL Western diet, (2) a TR group with restricted access to a Western diet (15 h/day, 12:00 to 3:00 Zeitgeber time [ZT]); and (3) an Ex/TR group fed a TR Western diet and subjected to physical exercise at 12:00 ZT. Mice in the AL group gained body weight rapidly during the 14-week observation period. With TR feeding, excessive weight gain, liver adiposity, visceral fat, and brown adipose tissue volume were effectively suppressed. Although TR feeding failed to decrease Oil Red O-stained aortic plaques in Apoe^−/− mice, physical exercise significantly decreased them. Neither TR feeding with exercise nor that without exercise decreased the mean area under the curve of the plasma cholesterol level or the fasting plasma glucose. Collectively, TR feeding of a Western diet prevented the development of obesity but failed to ameliorate atherosclerosis in Apoe^−/− mice.     

Regulation of Polyphosphoinositide Metabolism in Pea Plasma Membranes by Elicitor and Suppressor from a Pea Pathogen, Mycosphaerella pinodes

Effects of the elicitor and the suppressor from a pea pathogen,Mycosphaerella pinodes, on polyphosphoinositide metabolism inpea plasma membranes were examined in vitro. Lipid phosphorylationin the isolated pea plasma membrane was drastically stimulatedby the elicitor, but markedly inhibited by the suppressor. Asimilar inhibitory effect was observed by the treatment withorthovanadate or K-252a that blocked pisatin production inducedby the elicitor. Neomycin, an aminoglycoside antibiotic thatinteracts with the polyphosphoinositide metabolism, also affectedthe lipid phosphorylation in vitro and blocked the elicitor-inducedaccumulation of pisatin in vivo. These results suggest thatrapid changes of polyphosphoinositide metabolism in pea plasmamembranes is one of indispensable processes during the elicitationof defense responses. (Received January 22, 1992; Accepted March 23, 1992)     

Regulation of hepatic glucose metabolism by translocation of glucokinase between the nucleus and the cytoplasm in hepatocytes.

We studied the role of glucokinase translocation between the nucleus and the cytoplasm in hepatocytes. In cultured hepatocytes, both the translocation of glucokinase from the nucleus to the cytoplasm and the rate of glucose phosphorylation were increased when cells were incubated with high concentrations of glucose. The addition of low concentrations of fructose, which is known to stimulate glucose phosphorylation, stimulated both glucokinase translocation and glucose phosphorylation. There was a good correlation between the increase in cytoplasmic glucokinase induced by fructose and that in the glucose phosphorylation rate induced by fructose. Furthermore, we observed a linear relationship between cytoplasmic glucokinase activity and rate of glucose phosphorylation over various glucose concentrations in the absence or presence of fructose. These results indicate that glucose phosphorylation in hepatocytes depended on glucokinase in the cytoplasmic compartment--that is, the increase in the rate of glucose phosphorylation was due to the increase in translocation of glucokinase out of the nucleus. Also, oral administration of glucose, fructose, or glucose plus fructose to 24-h fasted rats induced translocation of glucokinase in the liver. All of these results indicate that hepatic glucose metabolism is regulated by the translocation of glucokinase.     

Preference for consonant music over dissonant music by an infant chimpanzee

It has been shown that humans prefer consonant sounds from the early stages of development. From a comparative psychological perspective, although previous studies have shown that birds and monkeys can discriminate between consonant and dissonant sounds, it remains unclear whether nonhumans have a spontaneous preference for consonant music over dissonant music as humans do. We report here that a five-month-old human-raised chimpanzee (Pan troglodytes) preferred consonant music. The infant chimpanzee consistently preferred to produce, with the aid of our computerized setup, consonant versions of music for a longer duration than dissonant versions. This result suggests that the preference for consonance is not unique to humans. Further, it supports the hypothesis that one major basis of musical appreciation has some evolutionary origins.     

Sex-Specific Posttranslational Regulation of the Gamete Fusogen GCS1 in the Isogamous Volvocine Alga Gonium pectorale

Male and female, generally defined based on differences in gamete size and motility, likely have multiple independent origins, appearing to have evolved from isogamous organisms in various eukaryotic lineages. Recent studies of the gamete fusogen GCS1/HAP2 indicate that this protein is deeply conserved across eukaryotes, and its exclusive and/or functional expression generally resides in males or in male homologues. However, little is known regarding the conserved or primitive molecular traits of males and females within eukaryotes. Here, using morphologically indistinguishable isogametes of the colonial volvocine Gonium pectorale, we demonstrated that GCS1 is differently regulated between the sexes. G. pectorale GCS1 molecules in one sex (homologous to male) are transported from the gamete cytoplasm to the protruded fusion site, whereas those of the other sex (females) are quickly degraded within the cytoplasm upon gamete activation. This molecular trait difference might be conserved across various eukaryotic lineages and may represent male and female prototypes originating from a common eukaryotic ancestor.     

Random integration of SV40 in SV40-transformed, immortalized human fibroblasts

We have studied the relationship between immortalization of SV40-transformed human embryonic fibroblasts and their SV40 integration sites. From several independently transformed cell pools, we have isolated clones which do not harbor unintegrated SV40 DNA. We have analysed whole-cell DNA from these clones, using the Southern blot method. Our results suggest that no specific integration sites in the cellular genome exist which are a prerequisite for the immortalization process. Although some integration sites were found to be predominant in pre-crisis clones, they could not be detected in the post-crisis clones. This suggests that none of these predominating sites is selected for during the crisis period.