Diet, Overfeeding, and Moderate Dietary Restriction in Control Sprague-Dawley Rats: II. Effects on Age-Related Proliferative and Degenerative Lesions

AbstractTaurine, a sulfur-containing amino acid, occurs at high concentrations in the skin, and plays a role in maintaining the homeostasis of the skin. We investigated the effects of aging on the content and localization of taurine in the skin of mice and rats. Taurine was extracted from the skin samples of hairless mice and Sprague Dawley rats, and the taurine content of the skin was determined by high-performance liquid chromatography (HPLC). The results of the investigation revealed that the taurine content in both the dermis and epidermis of hairless mice declined significantly with age. Similar age-related decline in the skin taurine content was also observed in rats. In contrast, the taurine content in the sole remained unchanged with age. An immunohistochemical analysis also revealed a decreased skin taurine content in aged animals compared with younger animals, although no significant differences in the localization of taurine were observed between the two age groups. Supplementation of the drinking water of aged mice with 3% (w/v) taurine for 4 weeks increased the taurine content of the epidermis, but not the dermis. The present study showed for the first time that the taurine content of the skin decreased with age in mice and rats, which may be related to the impairment of the skin homeostasis observed with aging. The decreased taurine content of the epidermis in aged animals was able to be rescued by taurine supplementation.

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Effects of TRPC6 Inactivation on Glomerulosclerosis and Renal Fibrosis in Aging Rats

Cells ◽

10.3390/cells10040856 ◽

2021 ◽

Vol 10 (4) ◽

pp. 856

Author(s):

Eun Young Kim ◽

Stuart E. Dryer

Keyword(s):

Renal Function ◽

Protective Effect ◽

Renal Fibrosis ◽

Transient Receptor Potential ◽

Smooth Muscle Actin ◽

Receptor Potential ◽

Sprague Dawley ◽

Age Related ◽

Sprague Dawley Rats ◽

Transient Receptor

Canonical transient receptor potential 6 (TRPC6) channels have been implicated in familial and acquired forms of focal and segmental glomerulosclerosis (FSGS) in patients and animal models, as well as in renal fibrosis following ureteral obstruction in mice. Aging also evokes declines in renal function owing to effects on almost every renal compartment in humans and rodents. Here, we have examined the role of TRPC6 in driving inflammation and fibrosis during aging in Sprague-Dawley rats. This was assessed in rats with non-functional TRPC6 channels owing to CRISPR-Cas9 deletion of a portion of the ankyrin repeat domain required for the assembly of functional TRPC6 channels (Trpc6del/del rats). Wild-type littermates (Trpc6wt/wt rats) were used as controls. Animals were evaluated at 2 months and 12 months of age. There was no sign of kidney disease at 2 months of age, regardless of genotype. However, by 12 months of age, all rats examined showed declines in renal function associated with albuminuria, azotemia and increased urine excretion of β2–microglobulin, a marker for proximal tubule pathology. These changes were equally severe in Trpc6wt/wt and Trpc6del/del rats. We also observed age-related increases in renal cortical expression of markers of fibrosis (α-smooth muscle actin and vimentin) and inflammation (NLRP3 and pro-IL−1β), and there was no detectable protective effect of TRPC6 inactivation. Tubulointerstitial fibrosis assessed from histology also appeared equally severe in Trpc6wt/wt and Trpc6del/del rats. By contrast, glomerular pathology, blindly scored from histological sections, suggested a significant protective effect of TRPC6 inactivation, but only within the glomerular compartment.

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Exercise training attenuates diet-induced reduction in metabolic rate

Journal of Applied Physiology ◽

10.1152/jappl.1990.68.6.2612 ◽

1990 ◽

Vol 68 (6) ◽

pp. 2612-2617 ◽

Cited By ~ 12

Author(s):

D. L. Ballor ◽

L. J. Tommerup ◽

D. P. Thomas ◽

D. B. Smith ◽

R. E. Keesey

Keyword(s):

Energy Expenditure ◽

Exercise Training ◽

Dietary Restriction ◽

Food Restriction ◽

Whole Body ◽

Daily Energy Expenditure ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

Daily Energy ◽

Whole Body Metabolism

The combined influence of exercise training and dietary restriction on daily energy expenditure was evaluated by exposing 48 male Sprague-Dawley rats to one of three food intake conditions [ad libitum (AL), moderately restricted (MR), or severely restricted (SR)] and to one of two exercise conditions [treadmill exercised (E) or cage confined (CC)]. After 10 wk of exercise and dietary restriction, the MR-CC and MR-E rats weighed 84 and 86%, respectively, of AL-CC, whereas the SR-CC and SR-E rats weighed 66 and 68% of AL-CC. Dietary restriction and subsequent weight loss produced significant reductions in both total and resting daily energy expenditure. Exercise partially reversed this effect, but the extent of this reversal diminished as the severity of dietary restriction was increased. These results raise the distinct possibility that inconsistencies in the current literature concerning the effects of exercise on whole body metabolism during periods of dietary restriction might be reconciled by an appreciation and an understanding of the influence that duration of exercise training and severity of food restriction have on this measure.

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The Process and Development Mechanism of Age-related Fibrosis in the Pancreatic Islets of Sprague-Dawley Rats: Immunohistochemical Detection of Myofibroblasts and Suppression Effect by Estrogen Treatment

Journal of Toxicologic Pathology ◽

10.1293/tox.26.1 ◽

2013 ◽

Vol 26 (1) ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Masako Imaoka ◽

Toshimasa Jindo ◽

Wataru Takasaki

Keyword(s):

Pancreatic Islets ◽

Estrogen Treatment ◽

Immunohistochemical Detection ◽

Sprague Dawley ◽

Suppression Effect ◽

Age Related ◽

Sprague Dawley Rats ◽

Development Mechanism

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Effect of the AIN-93M Purified Diet and Dietary Restriction on Survival in Sprague-Dawley Rats: Implications for Chronic Studies

Journal of Nutrition ◽

10.1093/jn/132.1.101 ◽

2002 ◽

Vol 132 (1) ◽

pp. 101-107 ◽

Cited By ~ 29

Author(s):

Peter H. Duffy ◽

Sherry M. Lewis ◽

Martha A. Mayhugh ◽

Andy McCracken ◽

Brett T. Thorn ◽

...

Keyword(s):

Dietary Restriction ◽

Sprague Dawley ◽

Sprague Dawley Rats

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Evidences Suggesting that Distinct Immunological and Cellular Responses to Light Damage Distinguishes Juvenile and Adult Rat Retinas

International Journal of Molecular Sciences ◽

10.3390/ijms20112744 ◽

2019 ◽

Vol 20 (11) ◽

pp. 2744

Author(s):

Anna Polosa ◽

Shasha Lv ◽

Wassila Ait Igrine ◽

Laura-Alexie Chevrolat ◽

Hyba Bessaklia ◽

...

Keyword(s):

Immune System ◽

Light Exposure ◽

Age Related Macular Degeneration ◽

Light Damage ◽

Sprague Dawley ◽

Adult Rat ◽

Age Related ◽

Degenerative Disorders ◽

Sprague Dawley Rats ◽

Dose Dependent

To unravel the mechanisms behind the higher resistance to light damage of juvenile (JR) versus adult (AR) rats, Sprague Dawley rats were exposed to a bright luminous environment of 10, 000 lux. The light-induced retinopathy (LIR) was assessed with histology, electroretinography and immunohistochemistry (IHC). In JR, 2 days of exposure induced the typical LIR, while >3 days added little LIR. IHC revealed a subtle migration of microglia (Iba1 marker) from the inner to the outer retina after 3 days of exposure in JR contrasting with the stronger reaction seen after 1 day in AR. Similarly, in JR, the Müller cells expressed less intense GFAP, CNTF and FGF2 staining compared to AR. Our results suggest that in JR the degree of retinal damage is not proportional to the duration of light exposure (i.e., dose-independent retinopathy), contrasting with the dose-dependent LIR reported in AR. The immature immune system in JR may explain the delayed and/or weaker inflammatory response compared to AR, a finding that would also point to the devastating contribution of the immune system in generating the LIR phenotype, a claim also advanced to explain the pathophysiology of other retinal degenerative disorders such as Age-related Macular Degeneration, Diabetic Retinopathy and Retinitis Pigmentosa.

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