Effects of Exercise Training on Glomerular Structure in Fructose-Fed Spontaneously Hypertensive Rats

Abstract

A high-fructose diet (HFD) has been shown to elevate blood pressure (BP) and to decrease insulin sensitivity in rats. Although running exercise can attenuate these phenomena, its effect on target organ protection is not clear. We investigated whether exercise training has renal protective effects in this model. Nine-week-old spontaneously hypertensive rats were allocated to groups that received HFD or a control diet (control group) for 15 weeks. At the age of 10 weeks, fructose-fed rats were allocated to groups that were given vehicle (FRU group), temocapril, an angiotensin converting enzyme inhibitor (TEM group), exercise training (EX group; treadmill running), or temocapril plus exercise training (TEM+EX group). BP was higher in the FRU group than in the control group. Exercise training tended to decrease BP and temocapril treatment decreased BP significantly. Proteinuria was similar in the five groups. Plasma leptin concentration and epididymal fat weight were lower in the EX and TEM+EX groups than in the FRU group. In the soleus muscle of the FRU group, the composite ratio of type I fiber was decreased and that of type IIa fiber was increased compared with those in the control group. Both temocapril and exercise training restored these ratios. The glomerular sclerosis index (GSI) was higher in the FRU group than in the control group. GSI was decreased equally in the TEM, EX, and TEM+EX groups and was positively correlated with plasma leptin concentration. The results suggest that exercise training ameliorates glomerular sclerosis through mechanisms other than a reduction in BP.

Low-Intensity Voluntary Running Lowers Blood Pressure with Simultaneous Improvement in Endothelium-Dependent Vasodilatation and Insulin Sensitivity in Aged Spontaneously Hypertensive Rats

“…It is well known that, in addition to realizing a hypotension effect with reduced renal and skeletal sympathetic activity, exercise helps to improve insulin sensitivity and other risk factors (21,22,(29)(30)(31)(32)(33)(34). However, some studies have shown that exercise did not reduce circulating insulin in genetic hypertensive rats (35,36). The exercise intensity employed in studies demonstrating no improvement in insulin sensitivity was relatively high (mostly 20 m/min for 60 min per day).…”

Antihypertensive Effect of Pleurotus nebrodensis in Spontaneously Hypertensive Rats

“…Further consideration is required to avoid warming or restraining rats. Der-Zen et al reported the use the tail-cuff method, which is commonly used to measure blood pressure in rats (as in this study) in a noninvasive automatic way after warming each animal in a heater for several min [9][10][11] . Single-dose studies using SHR have been conducted for M. aitchisonii, G. lucidum and Lyophyllum decastes 5,12,13) .…”

Curso temporal das alterações autonômicas e metabólicas da hipertensão por sobrecarga de frutose: papel do barorreflexo

“…Animais que são tratados com frutose, independentemente da via de administração, apresentam distúrbios semelhantes aqueles encontrados na SM, como resistência à insulina, aumento dos triglicerídeos e da insulina plasmática e hipertensão (YOSHIDA et al, 2003;BRITO et al, 2008;ARAUJO et al, 2015).…”

“…Chama a atenção, portanto, que as alterações autonômicas (ocorridas a partir da segunda semana) de fato precedem as alterações metabólicas (a partir da sétima semana) que vão caracterizar a síndrome metabólica induzida pela sobrecarga de frutose. Esse resultado está em acordo com outros semelhantes obtidos em camundongos (YOSHIDA et al, 2003). et al, 2010).…”