e Transcription factor Nrf2 (NF-E2-related factor 2) regulates a broad cytoprotective response to environmental stresses. Keap1 (Kelch-like ECH-associated protein 1) is an adaptor protein for cullin3-based ubiquitin E3 ligase and negatively regulates Nrf2. Whereas the Keap1-Nrf2 system plays important roles in oxidative stress response and metabolism, the roles Nrf2 plays in the prevention of diabetes mellitus remain elusive. Here we show that genetic activation of Nrf2 signaling by Keap1 gene hypomorphic knockdown (Keap1 flox/؊ ) markedly suppresses the onset of diabetes. When Keap1 flox/؊ mice were crossed with diabetic db/db mice, blood glucose levels became lower through improvement of both insulin secretion and insulin resistance. Keap1 flox/؊ also prevented high-calorie-diet-induced diabetes. Oral administration of the Nrf2 inducer CDDO-Im {oleanolic acid 1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl] imidazole} also attenuated diabetes in db/db mice. Nrf2 induction altered antioxidant-, energy consumption-, and gluconeogenesis-related gene expression in metabolic tissues. Thus, the Keap1-Nrf2 system is a critical target for preventing the onset of diabetes mellitus.

We determined the complete nucleotide sequence of the mitochondrial genome of an angiosperm, sugar beet (Beta vulgaris cv TK81-O). The 368 799 bp genome contains 29 protein, five rRNA and 25 tRNA genes, most of which are also shared by the mitochondrial genome of Arabidopsis thaliana, the only other completely sequenced angiosperm mitochondrial genome. However, four genes identified here (namely rps13, trnF-GAA, ccb577 and trnC2-GCA) are missing in Arabidopsis mitochondria. In addition, four genes found in Arabidopsis (ccb228, rpl2, rpl16 and trnY2-GUA) are entirely absent in sugar beet or present only in severely truncated form. Introns, duplicated sequences, additional reading frames and inserted foreign sequences (chloroplast, nuclear and plasmid DNA sequences) contribute significantly to the overall size of the sugar beet mitochondrial genome. Nevertheless, 55.6% of the genome has no obvious features of information. We identified a novel tRNA(Cys) gene (trnC2-GCA) which shows no sequence homology with any tRNA(Cys) genes reported so far in higher plants. Intriguingly, this tRNA gene is actually transcribed into a mature tRNA, whereas the native tRNA(Cys) gene (trnC1-GCA) is most likely a pseudogene.

Urinary neutrophil gelatinase-associated lipocalin (Ngal or lipocalin 2) is a very early and sensitive biomarker of kidney injury. Here we determined the origin and time course of Ngal appearance in several experimental and clinically relevant renal diseases. Urinary Ngal levels were found to be markedly increased in lipoatrophic- and streptozotocin-induced mouse models of diabetic nephropathy. In the latter mice, the angiotensin receptor blocker candesartan dramatically decreased urinary Ngal excretion. The reabsorption of Ngal by the proximal tubule was severely reduced in streptozotocin-induced diabetic mice, but upregulation of its mRNA and protein in the kidney was negligible, compared to those of control mice, suggesting that increased urinary Ngal was mainly due to impaired renal reabsorption. In the mouse model of unilateral ureteral obstruction, Ngal protein synthesis was dramatically increased in the dilated thick ascending limb of Henle and N was found in the urine present in the swollen pelvis of the ligated kidney. Five patients with nephrotic syndrome or interstitial nephritis had markedly elevated urinary Ngal levels at presentation, but these decreased in response to treatment. Our study shows that the urinary Ngal level may be useful for monitoring the status and treatment of diverse renal diseases reflecting defects in glomerular filtration barrier, proximal tubule reabsorption, and distal nephrons.

Abstract. Connective tissue growth factor (CTGF/CCN2) is one of the candidate factors mediating fibrogenic activity of TGF-␤. It was shown previously that the blockade of CTGF by antisense oligonucleotide (ODN) inhibits TGF-␤-induced production of fibronectin and type I collagen in cultured renal fibroblasts. The in vivo contribution of CTGF in renal interstitial fibrosis, however, remains to be clarified. With the use of a hydrodynamics-based gene transfer technique, the effects of CTGF antisense ODN are investigated in rat kidneys with unilateral ureteral obstruction (UUO). FITC-labeled ODN injection via the renal vein showed that the ODN was specifically introduced into the interstitium. At day 7 after UUO, the gene expression of CTGF, fibronectin, fibronectin ED-A, and ␣1(I) collagen in untreated or control ODN-treated obstructed kidneys was prominently upregulated. CTGF antisense ODN treatment, by contrast, markedly attenuated the induction of CTGF, fibronectin, fibronectin ED-A, and ␣1(I) collagen genes, whereas TGF-␤ gene upregulation was not affected. The antisense treatment also reduced interstitial deposition of CTGF, fibronectin ED-A, and type I collagen and the interstitial fibrotic areas. The number of myofibroblasts determined by the expression of ␣-smooth muscle actin was significantly decreased as well. Proliferation of tubular and interstitial cells was not altered with the treatment. These findings indicate that CTGF expression in the interstitium plays a crucial role in the progression of interstitial fibrosis but not in the proliferation of tubular and interstitial cells during UUO.

Abstract. Ghrelin is a novel hormone that possesses growth hormone (GH)-releasing, cardiovascular, and metabolic activities. Ghrelin is a unique acylated polypeptide, and the naked peptide, desacyl ghrelin, does not have the activity. This study examines plasma ghrelin concentrations in 41 patients with mild to severe renal diseases.

OBJECTIVE -Thiazolidinediones (TZDs), a class of insulin-sensitizing agents used clinically to treat type 2 diabetes, are also antiatherogenic. This study was designed to elucidate the relationship between the antiatherogenic and antidiabetic effects of pioglitazone, a TZD, in type 2 diabetic patients. RESEARCH DESIGN AND METHODS -A total of 136Japanese type 2 diabetic patients were included and divided into two groups: the pioglitazone-treated group (30 mg daily for 3 months) (n ϭ 70) and the untreated control group (n ϭ 66). The changes in glycolipid metabolism as well as plasma high-sensitivity C-reactive protein (CRP), leptin, adiponectin, and pulse wave velocity (PWV) were monitored to analyze the relationship between the antiatherogenic and antidiabetic effects of pioglitazone.RESULTS -The pioglitazone treatment significantly reduced hyperglycemia, hyperinsulinemia, and HbA 1c levels and increased plasma adiponectin concentrations relative to the control group (P Ͻ 0.01). It also significantly decreased CRP and PWV (P Ͻ 0.01). The antiatherogenic effect was observed in both the nonresponders showing Ͻ1% of reduction in HbA 1c (n ϭ 30) and responders showing Ͼ1% of reduction (n ϭ 40). ANCOVA revealed that treatment with pioglitazone was associated with a low CRP and PWV, independent of the changes in parameters related to glucose metabolism.CONCLUSIONS -This study represents the first demonstration of the antiatherogenic effect of pioglitazone in both nonresponders and responders with respect to its antidiabetic effect and suggests that pioglitazone can exert its antiatherogenic effect independently of its antidiabetic effect. Diabetes Care 26:2493-2499, 2003T ype 2 diabetes contributes to the risk of developing atherosclerotic diseases such as coronary heart disease and stroke and coronary restenosis after angioplasty or stenting (1-4). Therefore, it is of clinical importance to evaluate and treat cardiovascular complications in type 2 diabetic patients beyond glycemic control.Peroxisome proliferator-activated receptor-␥ (PPAR-␥) is a member of the nuclear receptor superfamily that, when activated by insulin sensitizers of the thiazolidinedione (TZD) class, including troglitazone, pioglitazone, and rosiglitazone, regulates a host of target genes (5,6). In humans with and animal models of insulin resistance and type 2 diabetes, TZDs can improve hyperglycemia and hyperinsulinemia and are currently used to manage type 2 diabetes (7). PPAR-␥ occurs abundantly in adipocytes where it regulates adipocyte differentiation (8), but it is also expressed in all major cell types participating in vascular injury, namely, endothelial cells, vascular smooth muscle cells (VSMCs), and macrophages (9,10). PPAR-␥ regulates the recruitment of monocytes to endothelial cells (11), modulates the inflammatory response in monocytes/macrophages and VSMCs (12-14), and inhibits macrophage foam cell formation and VSMCs proliferation and migration (13)(14)(15). In experimental models of atherosclerosis, ligandactivated PPAR-␥ prevents t...

Ghrelin is a novel growth hormone-releasing peptide with a unique acylated structure. Here we reveal that preproghrelin gene is expressed in the mouse kidney and glomerulus. We also show by reverse-phase high performance liquid chromatography coupled with radioimmunoassay that the mouse kidney does produce ghrelin. The ghrelin immunoreactivity in the mouse kidney is 6.79 þ 0.48 fmol/mg (n = 5), which is much more abundant than that in the mouse plasma of 0.339 þ 0.029 fmol/W Wl (n = 6). Furthermore, prepro-ghrelin gene is expressed in cultured rat mesangial cells, fibroblast-like NRK-49F cells and mouse podocytes, but not in rat epithelial cell-like NRK-52E cells. Ghrelin receptor gene is also expressed in the rat kidney. These findings demonstrate that the kidney, glomerulus and renal cells express prepro-ghrelin gene and ghrelin is produced locally in the kidney, and suggest the endocrine and/or paracrine roles of ghrelin in the kidney. ß

Synthetic a-human atrial natriuretic polypeptide was infused in patients with congestive heart failure (CHF) (New York Heart Association class III or IV) and in those without CHF. The infusion of atrial natriuretic polypeptide (ANP) at a rate of 0. 1 gg/kg/min significantly decreased pulmonary capillary wedge pressure and increased stroke volume index in all of the patients with CHF, whereas it decreased pulmonary capillary wedge pressure but caused no significant change in stroke volume index in the patients without CHF. Concomitant significant reductions in total systemic resistance were observed in both groups of patients. The ANP infusion significantly increased the urine volume, the excretion of sodium, and endogenous creatinine clearance in the patients without CHF. In the patients with CHF, it also showed a tendency to increase all these variables, but the urine volume did not correlate with the reduction in pulmonary capillary wedge pressure. The ANP infusion also decreased plasma aldosterone concentrations in these patients, although no significant difference was observed in the decrement of the plasma aldosterone concentration in the patients with and those without CHF. These findings indicate that the ANP infusion improves left ventricular function in patients with CHF, and suggest that this improvement results mainly from the vasodilating activity of ANP.Circulation 76, No. 1, 115-124, 1987. AFTER THE EPOCHAL discovery of the potent diuretic, natriuretic, and vasorelaxant activities in an extract from rat atria by de Bold et al. ,' multiple forms of natriuretic polypeptides with high and low molecular weights have been isolated fromn rat and human atria and implicated in the control of blood pressure, water, and electrolyte balance.2-1 Accumulating evidence indicates that a-atrial natriuretic polypeptide (a-ANP)