Recent work from this laboratory demonstrated potent inhibition of apoptosis in human alveolar epithelial cells (AECs) by the angiotensin-converting enzyme inhibitor captopril [B. D. Uhal, C. Gidea, R. Bargout, A. Bifero, O. Ibarra-Sunga, M. Papp, K. Flynn, and G. Filippatos. Am. J. Physiol. 275 ( Lung Cell. Mol. Physiol. 19): L1013–L1017, 1998]. On this basis, we hypothesized that apoptosis in this cell type might be induced by angiotensin II (ANG II) through its interaction with the ANG II receptor. Purified ANG II induced dose-dependent apoptosis in both the human AEC-derived A549 cell line and in primary type II pneumocytes isolated from adult Wistar rats as detected by nuclear and chromatin morphology, caspase-3 activity, and increased binding of annexin V. Apoptosis also was induced in primary rat AECs by purified angiotensinogen. The nonselective ANG II-receptor antagonist saralasin completely abrogated both ANG II- and angiotensinogen-induced apoptosis at a concentration of 50 μg/ml. With RT-PCR, both cell types expressed the ANG II-receptor subtypes 1 and 2 and angiotensin-converting enzyme (ACE). The nonthiol ACE inhibitor lisinopril blocked apoptosis induced by angiotensinogen, but not apoptosis induced by purified ANG II. These data demonstrate the presence of a functional ANG II-dependent pathway for apoptosis in human and rat AECs and suggest a role for the ANG II receptor and ACE in the induction of AEC apoptosis in vivo.

We report the synthesis and evaluation of 5-halogenated-1,2,3-triazoles as inhibitors of biotin protein ligase from Staphylococcus aureus. The halogenated compounds exhibit significantly improved antibacterial activity over their nonhalogenated counterparts. Importantly, the 5-fluoro-1,2,3-triazole compound 4c displays antibacterial activity against S. aureus ATCC49775 with a minimum inhibitory concentration (MIC) of 8 μg/mL.

To study anorexia in chronic renal failure (CRF) patients, we measured appetite-related hormones in seven CRF patients and four controls. Plasma concentrations and fractional changes from baseline (values from day 1, 0800) are listed as control vs. CRF (means Ϯ SE). Leptin, although higher in CRF (5.6 Ϯ 1.7 and 34 Ϯ 17 ng/ml), was suppressed after fasting; decrements were Ϫ51 Ϯ 9 and Ϫ55 Ϯ 8%. Nocturnal surge present during feeding was abolished upon fasting in both groups. Neuropeptide Y (NPY) was elevated in CRF (72 Ϯ 12 vs. 304 Ϯ 28 pg/ml, P ϭ 0.0002). NPY rhythm, reciprocal to that of leptin, was muted in CRF. Basal cortisol was similar in both groups (17 Ϯ 3 and 17 Ϯ 2 g/dl). In the controls, cortisol peaked in the morning and declined in the evening. CRF showed blunted cortisol suppression. Decrements were Ϫ61 Ϯ 3 and Ϫ20 Ϯ 9% at 1800 on day 1 (P ϭ 0.008) and Ϫ61 Ϯ 8 and Ϫ26 Ϯ 8% at 2000 on day 2 (P ϭ 0.02). Basal ACTH (25 Ϯ 5 and 54 Ϯ 16 pg/ml) as well as diurnal pattern was not statistically different between the groups. Baseline insulin was 6 Ϯ 1 and 20 Ϯ 9 U/ml. During fasting, insulin was suppressed to Ϫ64 Ϯ 10 and Ϫ51 Ϯ 9%, respectively. Upon refeeding, increments were 277 Ϯ 96 and 397 Ϯ 75%. Thus, in our CRF patients, anorexia was not due to excess leptin or deficient NPY. Impaired cortisol suppression should favor eating. Insulin suppression during fasting and secretion after feeding should enhance both eating and anabolism. The constant high NPY suggests increased tonic hypersecretion.hormones; appetite; uremia MALNUTRITION IS PREVALENT in chronic renal failure (CRF) patients, and anorexia is likely an important contributing factor (3). It has been reported that food consumption declines as renal function deteriorates (14). When uremia becomes severe, anorexia is believed to be prevalent and is characterized by food aversion, early satiety, and, sometimes, nausea and vomiting. Despite the prevalence of these symptoms, their pathogenesis has never been explained. We hypothesized that uremia-related anorexia may result from hypothalamic dysfunction. Renal failure patients are known to have a number of hormonal abnormalities due to hypothalamic disturbances; examples include diminished pulsatile gonadotropin and growth hormone secretion, lack of positive feedback effect of estrogen on LH secretion, excessive prolactin production, and delayed puberty (18). Because eating is, by and large, a central nervous system-regulated event (11), we studied some of the appetite-related hormones in response to fasting and refeeding in CRF patients. The results were compared with those obtained from normal subjects. We wondered whether CRF patients may have too much leptin or perhaps their leptin is not suppressed with food deprivation. We considered that these patients might be deficient in neuropeptide Y (NPY), a potent orexigenic peptide that mediates the effect of leptin in the hypothalamus (11). Knowing that cortisol is essential for eating in mammals and that corticotropin-releasing hormone is a potent anorex...

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