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A study was conducted to evaluate the quantitative relationship between cardiorespiratory fitness (CRF) and all-cause mortality associated with cardiovascular events among healthy men and women. Results indicated that better CRF led to a lesser mortality risk due to coronary heart disease (CHD) as well as cardiovascular disease (CVD).

Medical nutrition therapy and exercise therapy are the cornerstones of treatment for patients with type 2 diabetes; however, there has not been a nationwide study on the actual dietary intake and physical activity status of patients since the 2000s. We aimed to clarify this in Japanese patients with type 2 diabetes using data from the Japan Diabetes Complication and its Prevention prospective (JDCP), a nationwide study launched in 2007. A total of 1992 patients with type 2 diabetes, aged 40–75 years, completed either the Brief-type, self-administered Diet History Questionnaire (1643 patients) or International Physical Activity Questionnaire (1834 patients), and their data were analyzed in this study. Mean daily energy intake for all participants was 1686.8 kcal/day, and the mean proportions of carbohydrate, protein, and fat comprising total energy intake were 60.2, 16.2, and 23.6%, respectively. The patients in this study had similar energy and nutrient intake status to patients in the 1996 Japan Diabetes Complications Study; however, Japanese patients still had higher carbohydrate and lower fat consumption than patients with diabetes in Western countries. The physical activity questionnaire reported that 31.0% of patients did not have exercise habits; this was particularly noticeable in female patients and patients under the age of 65. BMI increased from 22.7 to 24.1 kg/m2 in men and 23.2 to 24.8 kg/m2 in women from 1996 to 2007, respectively. Further research is required to investigate how dietary intake and physical activity associates with the risk of developing complications in type 2 diabetes patients. [ABSTRACT FROM AUTHOR]

Parasympathetic stimulation of the heart, which provides protection from arrhythmias and sudden death, involves activation of the G protein--coupled inward rectifying [K.sup.+] channel GIRK1/4 and results in an acetylcholine-sensitive [K.sup.+] current, [I.sub.KACh]. We describe a unique relationship between lipid homeostasis, the lipid-sensitive transcription factor SREBP-1, regulation of the cardiac parasympathetic response, and the development of ventricular arrhythmia. In embryonic chick atrial myocytes, lipid lowering by culture in lipoprotein-depleted serum increased SREBP-1 levels, GIRK1 expression, and [I.sub.KACh] activation. Regulation of the GIRK1 promoter by SREBP-1 and lipid lowering was dependent on interaction with 2 tandem sterol response elements and an upstream E-box motif. Expression of dominant negative SREBP-1 (DN--SREBP-1) reversed the effect of lipid lowering on [I.sub.KACh] and GIRK1. In SREBP-1 knockout mice, both the response of the heart to parasympathetic stimulation and the expression of GIRK1 were reduced compared with WT. [I.sub.KACh], attenuated in atrial myocytes from SREBP-1 knockout mice, was stimulated by SREBP-1 expression. Following myocardial infarction, SREBP-1 knockout mice were twice as likely as WT mice to develop ventricular tachycardia in response to programmed ventricular stimulation. These results demonstrate a relationship between lipid metabolism and parasympathetic response that may play a role in arrhythmogenesis., Introduction The balance between the response of the heart to sympathetic and parasympathetic stimuli not only determines the rate and force of contraction but also plays a role in regulating [...]

Insulin resistance is often associated with obesity and can precipitate type 2 diabetes. To date, most known approaches that improve insulin resistance must be preceded by the amelioration of obesity and hepatosteatosis. Here, we show that this provision is not mandatory; insulin resistance and hyperglycemia are improved by the modification of hepatic fatty acid composition, even in the presence of persistent obesity and hepatosteatosis. Mice deficient for Elovl6, the gene encoding the elongase that catalyzes the conversion of palmitate to stearate, were generated and shown to become obese and develop hepatosteatosis when fed a high-fat diet or mated to leptin-deficient ob/ob mice. However, they showed marked protection from hyperinsulinemia, hyperglycemia and hyperleptinemia. Amelioration of insulin resistance was associated with restoration of hepatic insulin receptor substrate-2 and suppression of hepatic protein kinase C [epsilon] activity resulting in restoration of Akt phosphorylation. Collectively, these data show that hepatic fatty acid composition is a new determinant for insulin sensitivity that acts independently of cellular energy balance and stress. Inhibition of this elongase could be a new therapeutic approach for ameliorating insulin resistance, diabetes and cardiovascular risks, even in the presence of a continuing state of obesity., Author(s): Takashi Matsuzaka [1, 2]; Hitoshi Shimano (corresponding author) [1, 2]; Naoya Yahagi [2, 3]; Toyonori Kato [1]; Ayaka Atsumi [1]; Takashi Yamamoto [1]; Noriyuki Inoue [1]; Mayumi Ishikawa [1]; [...]

Using an expression cloning strategy, we have identified TFE3, a basic helix-loop-helix protein, as a transactivator of metabolic genes that are regulated through an E-box in their promoters. Adenovirus-mediated expression of TFE3 in hepatocytes in culture and in vivo strongly activated expression of IRS-2 and Akt and enhanced phosphorylation of insulin-signaling kinases such as Akt, glycogen synthase kinase 3[beta] and p70S6 kinase. TFE3 also induced hexokinase II (HK2) and insulin-induced gene 1 (INSIG1). These changes led to metabolic consequences, such as activation of glycogen and protein synthesis, but not lipogenesis, in liver. Collectively, plasma glucose levels were markedly reduced both in normal mice and in different mouse models of diabetes, including streptozotocin-treated, db/db and KK mice. Promoter analyses showed that IRS2, HK2 and INSIG1 are direct targets of TFE3. Activation of insulin signals in both insulin depletion and resistance suggests that TFE3 could be a therapeutic target for diabetes., Author(s): Yoshimi Nakagawa [1, 2]; Hitoshi Shimano (corresponding author) [1, 2]; Tomohiro Yoshikawa [1]; Tomohiro Ide [1]; Mariko Tamura [1]; Mika Furusawa [1]; Takashi Yamamoto [1]; Noriyuki Inoue [1]; Takashi [...]

In this study, using GK diabetic rats, we compared the effects of three insulin sensitizers on lipid oxidation and the aortic relaxation response. Eight-week-old rats were treated for 4 wk with either troglitazone or pioglitazone, both of which are thiazolidinediones, or with metformin. Despite the fact that only troglitazone has a similarity in structure to [alpha]-tocopherol, a potent antioxidant, the level of thiobarbituric acid-reactive substance was lower, and the lag time of the conjugated dienes was longer, in the blood samples from the rats in both troglitazone- and pioglitazone-treated groups. In contrast, another insulin sensitizer, metformin, failed to inhibit the oxidation of blood samples. The aortic vasorelaxation response was increased in both troglitazone- and metformin-treated groups compared with the untreated group. These findings suggest that thiazolidinediones have a beneficial effect on lipid oxidation irrespective of the drug's structural similarity to [alpha]-tocopherol. It is also suggested that the thiazolidinediones and metformin improve vascular function in diabetes. These effects may play a role in the prevention of atherosclerosis in diabetic patients. diabetes mellitus; low-density lipoprotein; endothelium; Goto-Kakizaki rats

A synthetase is a lipogenic enzyme controlled by SREBP-1 and energy status. Am J Physiol Endocrinol Metab 282: E222-E230, 2002; 10.1152/ajpendo.00189.2001.--DNA microarray analysis on upregulated genes in the livers from transgenic mice overexpressing nuclear sterol regulatory element-binding protein (SREBP)-1a, identified an espressed sequence tag (EST) encoding a part of murine cytosolic acetylcoenzyme A synthetase (ACAS). Northern blot analysis of the livers from transgenic mice demonstrated that this gene was highly induced by SREBP-1a, SREBP-1c, and SREBP-2. DNA sequencing of the 5' flanking region of the murine ACAS gene identified a sterol regulatory element with an adjacent Sp1 site. This region was shown to be responsible for SREBP binding and activation of the ACAS gene by gel shift and luciferase reporter gene assays. Hepatic and adipose tissue ACAS mRNA levels in normal mice were suppressed at fasting and markedly induced by refeeding, and this dietary regulation was nearly abolished in SREBP-1 knockout mice, suggesting that the nutritional regulation of the ACAS gene is controlled by SREBP-1. The ACAS gene was downregulated in streptozotocin-induced diabetic mice and was restored after insulin replacement, suggesting that diabetic status and insulin also regulate this gene. When acetate was administered, hepatic ACAS mRNA was negatively regulated. These data on dietary regulation and SREBP-1 control of ACAS gene expression demonstrate that ACAS is a novel hepatic lipogenic enzyme, providing further evidence that SREBP-1 and insulin control the supply of acetyl-CoA directly from cellular acetate for lipogenesis. However, its high conservation among different species and the wide range of its tissue distribution suggest that this enzyme might also play an important role in basic cellular energy metabolism. lipogenic enzyme; acetate; diabetes; insulin; transcription