Food Restriction Prevents Advanced Glycation End Product Accumulation and Retards Kidney Aging in Lean Rats

Abstract.Tissue content of advanced glycation end products (AGE) increases with age and contributes to the changes in structure and function of the renal and cardiovascular systems. The effect of chronic food restriction on this AGE accumulation was investigated in lean WAG/Rij rats. A 30% food restriction performed from 10 to 30 mo in female rats reduced their mean body weight from 240 ± 7 to 160 ± 12 g, but did not modify their survival. AGE collagen content increased from 14.3 ± 5.5 to 104.7 ± 13.0 arbitrary units per microgram (AU/μg) of hydroxyproline (OHPro) in kidney between 10 and 30 mo, and from 9.7 ± 1.2 to 310.6 ± 34.6 AU/μg OHPro in the abdominal aorta. Food restriction reduced AGE accumulation to 21.4 ± 3.3 and 74.6 ± 16.5 AU/μg OHPro in kidney and aorta of 30-mo-old animals. Similar results were found for collagen prepared from isolated glomeruli (7.8 ± 1.2, 81.2 ± 16.1, and 10.3 ± 4.3 AU/μg OHPro in 10-mo, 30-mo, and restricted 30-mo-old rats). Reduction of intrarenal and arterial AGE accumulation by food restriction was confirmed by immunostaining in optical microscopy. Age-related changes in arterial and kidney structures as polyuria and proteinuria were mainly prevented by food restriction. These data indicate that chronic food restriction reduces the accumulation of AGE and preserves the structure and function of the renal and cardiovascular systems in learn rats, although it did not affect survival of the animals between 10 and 30 mo.

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Food restriction prevents age-related polyuria by vasopressin-dependent recruitment of aquaporin-2

AJP Renal Physiology ◽

10.1152/ajprenal.0139.2001 ◽

2001 ◽

Vol 281 (6) ◽

pp. F1123-F1131 ◽

Cited By ~ 31

Author(s):

S. Combet ◽

L. Teillet ◽

G. Geelen ◽

B. Pitrat ◽

R. Gobin ◽

...

Keyword(s):

Food Restriction ◽

Marked Decrease ◽

Collecting Duct ◽

Apical Region ◽

Principal Cells ◽

Aquaporin 2 ◽

Age Related ◽

Old Rats ◽

Ad Libitum ◽

Chronic Food Restriction

First published August 8, 2001; 10.1152/ajprenal.00139.2001.—The mechanisms underlying the prevention of age-related polyuria by chronic food restriction were investigated in female WAG/Rij rats. The decreased osmolality of renal papilla observed in senescent rats was not corrected by food restriction. A reduced urea content in the inner medulla of senescent rats, fed ad libitum or food-restricted, was suggested by the marked decrease in expression of UT-A1 and UT-B1 urea transporters. Aquaporin-2 (AQP2) downregulation in the inner medulla of senescent rats was partially prevented by food restriction. Both AQP2 and the phosphorylated form of AQP2 (p-AQP2), the presence of which was diffuse within the cytoplasm of collecting duct principal cells in normally fed senescent rats, were preferentially targeted at the apical region of the cells in food-restricted senescent animals. Plasma vasopressin (AVP) was similar in 10- and 30-mo-old rats fed ad libitum, but was doubled in food-restricted 30-mo-old rats. This study indicates that 1) kidney aging is associated with a marked decrease in AQP2, UT-A1, and UT-B1 expression in the inner medulla and a reduced papillary osmolality; and 2) the prevention of age-related polyuria by chronic food restriction occurs through an improved recruitment of AQP2 and p-AQP2 to the apical membrane in inner medulla principal cells, permitted by increased plasma AVP concentration.

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Advanced glycation end products and vascular structure and function

Current Hypertension Reports ◽

10.1007/s11906-006-0025-8 ◽

2006 ◽

Vol 8 (6) ◽

pp. 472-478 ◽

Cited By ~ 20

Author(s):

Georgia Soldatos ◽

Mark Emmanuel Cooper

Keyword(s):

Advanced Glycation End Products ◽

Structure And Function ◽

Vascular Structure ◽

Advanced Glycation ◽

Glycation End Products ◽

End Products ◽

And Function

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Effects of trenbolone acetate and testosterone on growth and on plasma concentrations of corticosterone and ACTH in rats

Journal of Endocrinology ◽

10.1677/joe.0.1260461 ◽

1990 ◽

Vol 126 (3) ◽

pp. 461-466 ◽

Cited By ~ 8

Author(s):

M. N. Sillence ◽

R. G. Rodway

Keyword(s):

Weight Gain ◽

Growth Response ◽

Plasma Concentrations ◽

Female Rats ◽

Male Rats ◽

Adrenal Weight ◽

Trenbolone Acetate ◽

Male And Female Rats ◽

Age Related ◽

Old Rats

ABSTRACT The effects of trenbolone acetate (TBA) on growth and on plasma concentrations of corticosterone were examined in male and female rats. At 5 weeks of age, rats were injected with TBA (0·8 mg/kg) dissolved in peanut oil, or with oil alone, daily for 10 days. In female rats, TBA caused an increase in weight gain (20–38%), a reduction in adrenal weight (19%) and a reduction in plasma concentrations of corticosterone (55%). In contrast, TBA-treated male rats showed no significant increase in weight gain, no significant change in adrenal weight and no reduction in plasma concentrations of corticosterone. The mechanism by which adrenal activity was suppressed in TBA-treated female rats was examined and the response compared with that to testosterone. Female rats (8 weeks old) were injected daily either with oil vehicle, TBA (0·8 mg/kg) or testosterone propionate (0·8 mg/kg). Testosterone increased weight gain (24%), but the growth response to TBA treatment was significantly greater (97%). A reduction in plasma concentrations of corticosterone (45%) was again observed in response to TBA. However, testosterone increased plasma concentrations of corticosterone (52%) above those of control values. Neither androgen affected plasma concentrations of ACTH. Finally, the effects of TBA were examined in 6-week-old female rats, to characterize further the apparent age-related increase in responsiveness. The growth response of 6-week-old rats (60–74%) was intermediate between that seen in 5- and 8-week-old animals. It is concluded that part of the anabolic activity of TBA may be related to a reduction in circulating concentrations of corticosterone. The effect of TBA on corticosterone concentrations differs from that of the natural androgen, testosterone, and does not appear to be mediated by a reduction in plasma concentrations of ACTH. Journal of Endocrinology (1990) 126, 461–466

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Effects of Glucocorticoids on Age-Related Impairments of Hippocampal Structure and Function in Mice

Cellular and Molecular Neurobiology ◽

10.1007/s10571-007-9180-y ◽

2007 ◽

Vol 28 (2) ◽

pp. 277-291 ◽

Cited By ~ 22

Author(s):

Wen-Bin He ◽

Jun-Long Zhang ◽

Jin-Feng Hu ◽

Yun Zhang ◽

Takeo Machida ◽

...

Keyword(s):

Structure And Function ◽

Age Related ◽

And Function ◽

Hippocampal Structure

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Hyperhomocysteinemia disrupts retinal pigment epithelial structure and function with features of age-related macular degeneration

Oncotarget ◽

10.18632/oncotarget.7384 ◽

2016 ◽

Vol 7 (8) ◽

pp. 8532-8545 ◽

Cited By ~ 16

Author(s):

Ahmed S. Ibrahim ◽

Suchreet Mander ◽

Khaled A. Hussein ◽

Nehal M. Elsherbiny ◽

Sylvia B. Smith ◽

...

Keyword(s):

Macular Degeneration ◽

Retinal Pigment Epithelial ◽

Retinal Pigment ◽

Structure And Function ◽

Age Related Macular Degeneration ◽

Pigment Epithelial ◽

Age Related ◽

Epithelial Structure ◽

And Function

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Are skeletally mature female rats a suitable model to study osteoporosis?

Arquivos Brasileiros de Endocrinologia & Metabologia ◽

10.1590/s0004-27302012000400007 ◽

2012 ◽

Vol 56 (4) ◽

pp. 259-264 ◽

Cited By ~ 4

Author(s):

Claudia Cardoso Netto ◽

Vivian Cristine Correia Vieira ◽

Lizanka Paola Figueiredo Marinheiro ◽

Sherry Agellon ◽

Hope Weiler ◽

...

Keyword(s):

Bone Metabolism ◽

Type I Collagen ◽

Biomechanical Properties ◽

Mature Female ◽

Female Rats ◽

Suitable Model ◽

Type I ◽

Age Related ◽

Female Wistar Rats ◽

Old Rats

OBJECTIVE: To analyze if female Wistar rats at 56 weeks of age are a suitable model to study osteoporosis. MATERIALS AND METHODS: Female rats with 6 and 36 weeks of age (n = 8 per group) were kept over a 20-week period and fed a diet for mature rodents complete in terms of Ca, phosphorous, and vitamin D. Excised femurs were measured for bone mass using dual-energy x-ray absorptiometry, morphometry, and biomechanical properties. The following serum mar-kers of bone metabolism were analyzed: parathyroid hormone (PTH), osteocalcin (OC), osteoprotegerin (OPG), receptor activator of nuclear factor Κappa B ligand (RANKL), C-terminal peptides of type I collagen (CTX-I), total calcium, and alkaline phosphatase (ALP) activity. RESULTS: Rats at 56 weeks of age showed important bone metabolism differences when compared with the younger group, such as, highest diaphysis energy to failure, lowest levels of OC, CTX-I, and ALP, and elevated PTH, even with adequate dietary Ca. CONCLUSION: Rats at 26-week-old rats may be too young to study age-related bone loss, whereas the 56-week-old rats may be good models to represent the early stages of age-related changes in bone metabolism.

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