Acute effect of high-intensity interval training exercise on redox status in the ovaries of rats fed a high-fat diet.

This study demonstrates the effect of a single high-intensity interval training (HIIT) session on the redox status of rat ovaries with excess adiposity. Forty Wistar female rats (mean (±s.e.m.) weight 94.40 ± 13.40 g) were divided into two groups and fed either a standard diet (SD) or a high-fat diet (HFD) for 62 days. At the end of this period, the rats were subjected to a single HIIT session and were killed 24 h after exercise. Both groups subjected to exercise (SDex and HFDex) generated a significantly higher antioxidant environment by presenting a higher thiol content, which represents a lower oxidation rate of GSH than their respective controls (SD and HFD). The percentage of morphologically normal primary follicles decreased, whereas that of antral follicles increased, in the SDex group. In addition, the HFD group had a higher percentage of degenerated antral follicles than the SD and SDex groups. Cells immunoreactive for α-smooth muscle actin were seen in the cortical stroma and thecal layer enclosing late secondary and tertiary follicles in all groups. Moreover, heme oxygenase and cytochrome P450 family 19 subfamily A member 1 (Cyp19A1) labelling was seen in all antral follicles. Progesterone concentrations were significantly higher in the HFDex than SDex group. In conclusion, this study indicates that a single session of HIIT may result in an improvement in ovary redox status because of metabolic muscle activity by inducing physiological adaptation after exercise in a paracrine manner.

Neuroprotector Effect of Daily 8-Minutes of High-Intensity Interval Training in Rat Aß1-42 Alzheimer Disease Model.

BACKGROUND: Alzheimer's disease (AD) is the most common and irreversible neurodegenerative disorder, and amyloid peptide plays a central role in its pathogenesis. Physical training contributes as a beneficial adaptation to AD. However, these effects may be underestimated because much of the literature used fixed training prescription variables (intensity and volume) throughout the protocol. Moreover, researchers poorly understand whether chronic high-intensity interval training (HIIT) exerts similar effects on the brain tissue of individuals with AD. OBJECTIVE: This study evaluated the effect of 8 minutes of HIIT with incremental overload in an AD model. METHODS: Forty male Wistar rats were divided into four groups: an untrained Sham group, Sham trained group, Aß1-42 (Alzheimer's) untrained group, and Aß1-42 (Alzheimer's) trained group (n=10 rats per group). Animals underwent stereotactic surgery and received a hippocampal injection of Aß1-42 or a saline solution. Seven days after surgery, two weeks of treadmill adaptation followed by a maximal running test (MRT) was performed. Then, animals were subjected to eight weeks of HIIT. Rats were sacrificed 24 h after the behavioral tests (open field and Morris water maze), hippocampal tissue was extracted to analyze the redox balance and BDNF/TrkB pathway, and neuritic plaques (NP) were detected by evaluating silver impregnation. RESULTS: The AD trained group presented a physical capacity amelioration every two weeks and locomotor, learning, and memory improvements (p<0.05). These effects were accompanied by increased CAT and SOD levels, followed by decreased lipid peroxidation (p<0.05). Furthermore, increased activation of the BDNF/TrkB (p<0.05) pathway and decreased NP was observed. CONCLUSION: Based on these results, MRT was essential for an excellent chronic training protocol prescription and overload adjustment. Therefore, 8 minutes of HIIT daily for 8 weeks may reduce behavioral deficits by promoting a positive redox balance and increased activity of the BDNF/TrkB pathway that may contribute to NP attenuation.

Endothelium-dependent vasorelaxant effects of the essential oil from aerial parts of Alpinia zerumbet and its main constituent 1,8-cineole in rats.

Vasorelaxant effects of essential oil of Alpinia zerumbet (EOAZ) and its main constituent, 1,8-cineole (CIN) were studied. In rat isolated aorta preparations with intact endothelium, EOAZ (0.01-3000 microg/ml) induced significant but incomplete relaxation of the phenylephrine-induced contraction, an effect that was abolished by removal of vascular endothelium. However, at the same concentrations (0.01-3000 microg/ml corresponding to 0.0000647-19.5 mM), CIN induced a complete vasorelaxant effects (IC(50)=663.2+/-63.8 microg/ml) that were significantly reduced in endothelium-denuded rings (IC(50)=1620.6+/-35.7 microg/ml). Neither EOAZ nor CIN affected the basal tonus of isolated aorta. Vasorelaxant effects of both EOAZ and CIN remained unaffected by the addition of tetraethylamonium chloride (500 microM) or indomethacin (10 microM) into the bath, but were significantly reduced by N(G)-nitro-L-arginine methyl ester (100 microM). It is concluded that EOAZ induces a potent vasorelaxant effect that could not be fully attributed to the actions of the main constituent CIN, and appears totally dependent on the integrity of a functional vascular endothelium. The data is novel and corroborate the popular use of A. zerumbet for the treatment of hypertension.

Effects of 1,8-cineole on electrophysiological parameters of neurons of the rat superior cervical ganglion.

1. 1,8-Cineole is a non-toxic small terpenoid oxide believed to have medicinal properties in folk medicine. It has been shown to have various pharmacological effects, including blockade of the compound action potential (AP). In the present study, using intracellular recording techniques, we investigated the effects of 1,8-cineole on the electrophysiological parameters of neurons of the superior cervical ganglion (SCG) in rats. 2. 1,8-Cineole (0.1-6 mmol/L) showed reversible and concentration-dependent effects on various electrophysiological parameters. At 3 and 6 mmol/L, but not at 0.1 and 1 mmol/L, 1,8-cineole significantly diminished the input resistance (R(i)) and altered the resting potential (E(m)) to more positive values. At 6 mmol/L, 1,8-cineole completely blocked all APs within 2.7 +/- 0.6 min (n = 12). In neurons exposed to 3 and 1 mmol/L 1,8-cineole, the effects regarding excitability varied from complete AP blockade to minor inhibition of AP parameters. The depolarization of E(m) and the decrease in R(i) induced by 6 mmol/L 1,8-cineole were unaltered by 200 micromol/L niflumic acid, a well known blocker of Ca(2+)-activated Cl(-) currents. 3. Significant correlations (Pearson correlation test) were found between changes in E(m) and decreases in AP amplitude (r = -0.893; P < 0.00282) and maximum ascendant inclination (r = -0.799; P < 0.0173), but not for maximum descendant inclination (r = 0.598; P < 0.117). Application of current to restore the transmembrane potential equal to control E(m) values in the presence of 6 mmol/L 1,8-cineole resulted in the partial recovery of AP. 4. The present study shows that 1,8-cineole effectively blocks the excitability of SCG neurons, probably through various mechanisms, one of which acts indirectly via depolarization of the neuronal cytoplasmatic membrane.