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Query: UMLS:C0028754 (obesity)
 124,988 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study was undertaken to examine the appropriateness of the obese overfed rat and the obese Zucker rat as animal models for evaluating drug disposition changes in human obesity. It was found that 11 of 12 characteristics that control or influence drug clearance and volume of drug distribution in obese humans were qualitatively reproduced in the obese overfed rat. In contrast, existing literature shows that the obese Zucker rat resembles the obese human in only five of 12 characteristics, with meaningful discrepancies in fat-free mass, creatinine clearance, and thyroid function. Perhaps of greatest significance were changes in hepatic cytochrome P-450, which increased in proportion to total body mass in the obese overfed rat but remain unchanged in the Zucker rat. Although P-450 status in human obesity is unknown, the overfed rat model provides an opportunity for examining increased oxidative drug elimination that appears as an established feature of human obesity. In conclusion, the obese overfed rat appears to be superior to the obese Zucker rat as an animal model for evaluating the pharmacological consequences of human obesity, particularly those in which reproducing drug pharmacokinetics is an important consideration.
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PMID:Pharmacokinetic characteristics of the obese overfed rat. 270 95

The SHR/N corpulent (cp) rat is a genetically obese rat that develops hyperglycemia, hyperinsulinemia, and proteinuria. This study was designed to evaluate the effects of high carbohydrate (CHO) intake on renal function and structure in this animal model and to determine whether the renal effects are related to the type of CHO ingested. Two groups of 5-wk-old obese male SHR/N-cp rats and lean male littermates were fed diets containing 54% CHO in the form of sucrose or starch. After 12 wk, renal function parameters, including creatinine clearance, urinary glucose excretion, and urinary protein excretion, were measured. Renal morphology was evaluated by semiquantitative light and electron microscopy. On either diet, obese rats had significantly higher urinary glucose and protein excretions than their lean littermates. Mean creatinine clearance (ml/min) in obese rats did not differ significantly from values observed in lean rats. When corrected for body weight, creatinine clearance (ml.min-1.kg-1) tended to be lower in obese than in lean rats, but the difference was significant (P less than .02) only for obese and lean sucrose-fed animals. Obese rats fed sucrose compared with their obese counterparts fed starch had higher body weight (+8%, P less than .05), glucose excretion (+63%, P less than .02), and protein excretion (+242%, P less than .005). In obese rats, protein excretion correlated with glucose excretion (r = .71, P less than .01). Glomerular lesions consisting of mesangial expansion and intercapillary nodules were found in obese but not in lean rats. Moreover, obese rats fed sucrose had a significantly greater number of involved glomeruli than obese rats fed starch.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of carbohydrate intake on kidney function and structure in SHR/N-cp rats. A new model of NIDDM. 272 22

Twenty-four type 1 and type 2 diabetic patients with obesity and overt nephropathy were studied for 12 months after hypocaloric diet change from 1870 to 1410 kcal/day (without changes of protein:carbohydrate ratio). Several parameters were evaluated: arterial blood pressure, blood glucose, fructosamine, HbA1c, proteinuria, albuminuria, glomerular filtration rate (GFR), creatinine clearance, triglycerides, HDL and total cholesterol. A significant reduction of body weight (body mass index from 33 +/- 1.6 to 26 +/- 1.8 kg/m2, P less than 0.001), concomitantly with a decrease of blood pressure levels (P less than 0.002) was demonstrated at the end of the study. Triglyceride (P less than 0.002), HDL (P less than 0.002), HDL (P less than 0.05) and total cholesterol (P less than 0.01) levels were reduced after diet-therapy, while a mild improvement of glycometabolic profile was observed in the same period. A marked decrease of proteinuria (from 1280 +/- 511 to 623 +/- 307 mg/24 h, P less than 0.01) and albuminuria (from 723 +/- 388 to 492 +/- 170 micrograms/min, P less than 0.01), and an improvement of GFR (from 66 +/- 13 to 81 +/- 11 ml/min/1.73 m2, P less than 0.01) and creatinine clearance (from 79 +/- 14 to 91 +/- 13 ml/min, P less than 0.01) was demonstrated after 12 months of diet-treatment. Our data suggest that body weight reduction by hypocaloric diet may delay the progression of clinical nephropathy in obese diabetic patients.
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PMID:Effects of diet-therapy on urinary protein excretion albuminuria and renal haemodynamic function in obese diabetic patients with overt nephropathy. 274 32

A double blind placebo controlled study was carried out in 40 subjects newly referred for treatment for obesity to determine the effects of the new thermogenic beta adrenoceptor agonist BRL 26830A. The subjects were randomised to receive either BRL 26830A, 200 mg daily for two weeks then 400 mg daily, or placebo for 18 weeks, and all were instructed to follow a 3.35 MJ diet that was low in fat and high in fibre. Weight loss was 15.4 (SD 6.6) kg in subjects given BRL 26830A compared with 10.0 (5.9) kg in those given placebo (p = 0.02). The relative weight loss was 0.93 (0.39%) a week with BRL 26830A and 0.61 (0.38)% with placebo (p = 0.02). Urinary excretion of nitrogen was similar in both groups, whereas measurements of skinfold thickness indicated a 4.1 kg difference in the amount of fat lost, suggesting that weight loss with BRL 26830A was mainly from adipose and not lean tissue. BRL 26830A had no effect on resting pulse rate or pressor effects on either diastolic or systolic blood pressure. No significant differences were found between the two groups in serum cholesterol concentration, percentage of high density lipoprotein cholesterol, plasma concentrations of glucose and insulin, the ratio of glucose to insulin, serum concentrations of triiodothyronine and thyroxine, and creatinine clearance. Short term administration of BRL 26830A to six subjects who had taken the drug for 18 weeks showed that the expenditure of energy increased by 11.6% during the second hour after administration, which suggests that BRL 26830A may enhance weight loss thermogenically. BRL 26830A may be a useful drug in the treatment of obesity.
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PMID:Weight loss in obese subjects on a restricted diet given BRL 26830A, a new atypical beta adrenoceptor agonist. 289 68

Obese humans suffer from excessive organ dysfunction, altered drug pharmacokinetics and may be at increased risk of various drug toxicities. A recent report shows that gentamicin nephrotoxicity in critically ill patients is more frequent and more severe than usual in individuals who are substantially overweight. The present study utilizes an overfed rat model to examine the influence of obesity on the nephrotoxic potential of gentamicin. After 52 weeks on an energy-dense diet, obese animals outweighed pellet controls by more than 80% (913 +/- 86 vs. 507 +/- 52 g; X +/- S.D., n = 7). When animals were treated twice daily for 6 days with 30 mg/kg of gentamicin i.p. based on total body mass, obese rats sustained more cortical necrosis than control (median score 3+ vs. 0), higher serum creatinine (4.36 +/- 2.72 vs. 0.71 +/- 0.17) and greater creatinine adjusted N-acetyl hexosaminidase excretion. The impact of obesity on intrinsic susceptibility to gentamicin nephrotoxicity was assessed by dosing animals for 5 days to ideal body mass plus 40% of excess body mass, the current clinical practice for achieving normal gentamicin concentrations in obese patients. Obese rats again sustained more frequent and severe cortical necrosis (2+ vs. 0) and excreted more N-acetyl hexosaminidase than control animals. Urine pH averaged 1.7 U below normal in obese animals, but restoration to normal values by 2 weeks on the pellet diet did not diminish the toxicity increase. Results from the overfed rat closely resemble the recent clinical observation that obese patients sustain more frequent and severe kidney damage from aminoglycoside antibiotics.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Obesity as a risk factor in drug-induced organ injury. IV. Increased gentamicin nephrotoxicity in the obese overfed rat. 291 69

This study was undertaken to evaluate the effect of obesity on the postmenopausal bone mass. Bone mineral density, measured by dual photon absorptiometry of the lumbar spine, serum osteocalcin (OC), fasting urinary calcium to creatinine (Ca:Cr), serum estradiol (E2) dehydroepiandrosterone (DHA) and testosterone (T) were measured in 176 women aged 45-71 years. Women were divided into four groups according to their menopausal status and their weight: 49 perimenopausal, 28 obese perimenopausal, 49 obese postmenopausal. Within each population (perimenopausal and postmenopausal), mean age was the same, only weight was significantly different (p less than 0.0001). For the two groups of postmenopausal women mean interval since menopause (YSM) was the same (5.8 +/- 3 and 5.4 +/- 5 yr). Comparison between groups revealed a significant effect of menopausal status and obesity on BMD and bone turnover. As compared to perimenopausal women, BMD was lower, OC and Ca: Cr higher only in nonobese-postmenopausal women. E2, T, DHA did not differ between the two groups of postmenopausal women. The results of this study suggest that even moderate obesity can play a protective role on postmenopausal bone loss.
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PMID:Obesity and postmenopausal bone loss: the influence of obesity on vertebral density and bone turnover in postmenopausal women. 296 34

Serum immunoreactive parathyroid hormone (PTH) is increased in obese as compared with nonobese subjects and declines with weight loss. To determine whether alteration of the vitamin D-endocrine system occurs in obesity and whether ensuing secondary hyperparathyroidism is associated with a reduction in urinary calcium, a study was performed in 12 obese white individuals, five men and seven women, and 14 nonobese white subjects, eight men and six women, ranging in age from 20 to 35 yr. Body weight averaged 106 +/- 6 kg in the obese and 68 +/- 2 kg in the nonobese subjects (P less than 0.01). Each of them were hospitalized on a metabolic ward and were given a constant daily diet containing 400 mg of calcium and 900 mg of phosphorus. Whereas mean serum calcium, serum ionized calcium, and serum phosphorus were the same in the two groups, mean serum immunoreactive PTH (518 +/- 48 vs. 243 +/- 33 pg/ml, P less than 0.001), mean serum 1,25-dihydroxyvitamin D [1,25(OH)2D] (37 +/- 2 vs. 29 +/- 2, P less than 0.01), and mean serum Gla protein (33 +/- 2 vs. 24 +/- 2 ng/ml, P less than 0.02) were significantly higher, and mean serum 25-hydroxyvitamin D (25-OHD) (8 +/- 1 vs. 20 +/- 2 ng/ml, P less than 0.001) was significantly lower in the obese than in the nonobese men and women. Mean urinary phosphorus was the same in the two groups, whereas mean urinary calcium (115 +/- 10 vs. 166 +/- 13 mg/d, P less than 0.01) was significantly lower, and mean urinary cyclic AMP (3.18 +/- 0.43 vs. 1.84 +/- 0.25 nM/dl GF, P less than 0.01) and creatinine clearance (216 +/- 13 vs. 173 +/- 6 liter/d, P less than 0.01) were significantly higher in the obese than in the nonobese individuals. There was a significant positive correlation between percentage of ideal body weight and urinary cyclic AMP (r = 0.524, P less than 0.01) and between percentage of ideal body weight and serum immunoreactive PTH (r = 0.717, P less than 0.01) in the two groups. The results provide evidence that alteration of the vitamin D-endocrine system in obese subjects is characterized by secondary hyperparathyroidism which is associated with enhanced renal tubular reabsorption of calcium and increased circulating 1,25(OH)2D. The reduction of serum 25-OHD in them is attributed to feedback inhibition of hepatic synthesis of the precursor by the increased serum 1,25(OH)2D.
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PMID:Evidence for alteration of the vitamin D-endocrine system in obese subjects. 299 40

The relation between hypertension and diabetic nephropathy is complex. Nephropathy is probably involved in the elevated blood pressure found in diabetic patients. In maturity onset diabetes, patients may also have hypertension which is associated with obesity or essential hypertension. It has been suggested that in both types of diabetes, hypertension enhances the development of diabetic nephropathy. Moreover, an aggressive antihypertensive treatment seems able to reduce rate of decline in kidney function in insulin-dependent diabetic patients with patent nephropathy. In this work, creatinine clearance and microalbuminuria in 20 diabetic patients (mostly with maturity-onset-diabetes) with known moderate and effectively treated hypertension were therefore measured and the results were compared with those for 18 normotensive diabetic patients and 22 controls. Duration of diabetes was from one to 26 years (mean: 11 years) and duration of hypertension was from one to 35 years (mean: 10 years). Patients and controls had normal serum creatinine and proteinuria below 0.1 g/l. Microalbuminuria was measured by immunonephelometric assay using specific antiserum (sensitivity = 1.5 mg/l; intra and interassay coefficients: 6.5% and 8% respectively). The highest value was observed in hypertensive diabetic patients with retinopathy (group 1). But hypertensive patients without retinopathy (group 2) and normotensive patients also had significantly increased microalbuminuria. In group 1, microalbuminuria was significantly higher than in group 2. The creatinine clearance was reduced in groups 1 and 2 versus normotensive diabetics, but hypertensive patients were older.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Microalbuminuria in diabetics with moderate hypertension]. 309 93

In this study, we investigated the usefulness of the determination of evening urinary free corticoids/creatinine in samples collected from 20.00 to 24.00 h as a screening test in Cushing's syndrome. In controls (N = 61) the ratio values ranged from 1.1 to 9.4 mumol/mol, whereas in patients with Cushing's syndrome (N = 20), they ranged from 27.5 to 855.5 mumol/mol. However, in 28% of patients with major obesity (greater than 50% overweight) and no hypercortisolism, the ratio values were between 9.4 to 27.8 mumol/mol. A short (10 days) hypocaloric diet induced a decrease in the values in 75% of these patients; the normal range was reached in 50% of them. In addition, the evening urinary free corticoids/creatinine was slightly abnormal in 8 out of 10 patients with incidentally discovered 'silent' adrenal adenomas, whereas it was normal in all 6 with other adrenal masses. In conclusion, evening urinary free corticoids/creatinine is easy to obtain and it reaches a higher sensitivity (100%) and specificity (97%) than the 24 h urinary free corticoids. In the case of borderline values, the presence of overweight should be taken into account.
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PMID:Evening urinary free corticoids: a screening test in Cushing's syndrome and incidentally discovered adrenal tumours. 318 14

A 65-year-old woman of normal weight, hospitalized because of pleuritis, was found to have chronic renal failure (creatinine clearance 20 ml/min). Renal biopsy (light and electron-microscopy) revealed nodular glomerulosclerosis (Kimmerstiel-Wilson disease), described as a diabetes-specific renal change. Fundoscopy discovered bilateral proliferative retinopathy as seen in diabetes. But oral and intravenous glucose tolerance tests were normal, excluding a manifest diabetic metabolic disorder. No other cause of the glomerulosclerosis (such as amyloidosis or multiple myeloma) was found. The patient had been overweight for a time when younger, reversed by dieting. It is suggested that the "diabetic" changes in the kidneys and eyes without diabetes could be the result of a transitory disorder of glucose tolerance during the period of obesity.
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PMID:["Diabetic" proliferative retinopathy and nodular glomerulosclerosis without diabetes mellitus]. 319 24


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