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1.
Circulation ; 145(6): 448-464, 2022 02 08.
Article in English | MEDLINE | ID: mdl-35034472

ABSTRACT

BACKGROUND: The nuclear receptor Rev-erbα/ß, a key component of the circadian clock, emerges as a drug target for heart diseases, but the function of cardiac Rev-erb has not been studied in vivo. Circadian disruption is implicated in heart diseases, but it is unknown whether cardiac molecular clock dysfunction is associated with the progression of any naturally occurring human heart diseases. Obesity paradox refers to the seemingly protective role of obesity for heart failure, but the mechanism is unclear. METHODS: We generated mouse lines with cardiac-specific Rev-erbα/ß knockout (KO), characterized cardiac phenotype, conducted multi-omics (RNA-sequencing, chromatin immunoprecipitation sequencing, proteomics, and metabolomics) analyses, and performed dietary and pharmacological rescue experiments to assess the time-of-the-day effects. We compared the temporal pattern of cardiac clock gene expression with the cardiac dilation severity in failing human hearts. RESULTS: KO mice display progressive dilated cardiomyopathy and lethal heart failure. Inducible ablation of Rev-erbα/ß in adult hearts causes similar phenotypes. Impaired fatty acid oxidation in the KO myocardium, in particular, in the light cycle, precedes contractile dysfunctions with a reciprocal overreliance on carbohydrate utilization, in particular, in the dark cycle. Increasing dietary lipid or sugar supply in the dark cycle does not affect cardiac dysfunctions in KO mice. However, obesity coupled with systemic insulin resistance paradoxically ameliorates cardiac dysfunctions in KO mice, associated with rescued expression of lipid oxidation genes only in the light cycle in phase with increased fatty acid availability from adipose lipolysis. Inhibition of glycolysis in the light cycle and lipid oxidation in the dark cycle, but not vice versa, ameliorate cardiac dysfunctions in KO mice. Altered temporal patterns of cardiac Rev-erb gene expression correlate with the cardiac dilation severity in human hearts with dilated cardiomyopathy. CONCLUSIONS: The study delineates temporal coordination between clock-mediated anticipation and nutrient-induced response in myocardial metabolism at multi-omics levels. The obesity paradox is attributable to increased cardiac lipid supply from adipose lipolysis in the fasting cycle due to systemic insulin resistance and adiposity. Cardiac molecular chronotypes may be involved in human dilated cardiomyopathy. Myocardial bioenergetics downstream of Rev-erb may be a chronotherapy target in treating heart failure and dilated cardiomyopathy.


Subject(s)
Circadian Rhythm/physiology , Myocardium/pathology , Obesity/physiopathology , Animals , Circadian Clocks , Heart Diseases , Humans , Mice , Mice, Knockout
2.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 1991-3, 2005.
Article in English | MEDLINE | ID: mdl-17282614

ABSTRACT

We could get valuable information about various diseases by analyzing urine of patients. For the diabetics, it has been very important to know the glucose concentration in their urine. Until now, there have been many methods to estimate the concentration but they were invasive and annoyed patients. The Low-Resolution Raman Spectroscopy (LRRS) could be an alternative method to be non-invasive and unconscious for patients who want to check the amount of their urine components. LRRS is not expensive and smaller than laboratory Raman spectroscope. And we want to attach it to the common toilet bowl. For the reason, we got the spectrum of diluted urine and predicted the glucose concentration. In addition, we tried to find very small amount of glucose. LRRS was adequate for measuring Raman signal of diluted urine and could find very small amount of glucose. This system will realize the observation of one's health condition every day without awareness.

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