Abstract: Behavioral disturbances are observed in most patients suffering from diabetes. According to some evidence, pro-inflammatory cytokines have a key role both in diabetes and behavioral disorders, such as anxiety and depression. In this study, the effect of chronic administration of loganin, as a bioflavonoid, was investigated on pro-inflammatory cytokines and depression- and anxiety-like behaviors in streptozotocin-induced diabetes in male Wistar rats. Blood levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were assessed by enzymelinked immunosorbent assay method. Depression- and anxiety-like behaviors were evaluated by forced swimming test (FST), elevated plus maze (EPM), and open field test (OFT), respectively. Body weight was also measured before the interventions and after the experiments in all groups. Our findings show that loganin-treated animals had significantly lower serum concentrations of IL-6 and TNF-α compared with the diabetic group. In the EPM test, loganin treatment significantly increased the percentage of the open arm time and open arm entries. Moreover, loganin treatment significantly decreased the grooming time and restored distance traveled and center crossing in the OFT. However, it decreased immobility time in the FST. Loganin treatment also significantly restored body weight gain and attenuated blood glucose changes in the diabetic rats. These results indicate that loganin possibly alleviates depression- and anxiety-like behaviors associated with diabetes through lowering the blood glucose and pro-inflammatory cytokine levels. More research is required to show the exact mechanism of antidepressant and anxiolytic effects of loganin in diabetes.
Keywords: diabetes, anxiety, depression, loganin, IL-6, TNF-α
Abstract: Prenatal hypoxia–ischemia (HI) is a major cause of mortality and chronic neurological diseases in newborns. HI contributes to the emergence of several neurological disorders such as cognitive and behavioral deficits due to the atypical brain development. This study aimed at assessing the effects of prenatal HI on the spatial memory and aggression of rats during adolescence. Pregnant rats were divided into treatment and control groups. The rats of the treatment groups underwent unilateral ligation of the uterine artery on pregnancy day 7, 12, or 17. The offspring of these rats were tested for spatial memory and aggression when they reached 33 days of age. It has been found that the percentages of alternations in the Y-maze and the number of crossings in the Morris water maze tests of the HI groups were lower than those of the control groups. The total offense and defense aggression scores of the HI groups were higher than those of the control groups. In conclusion, the longer the duration of HI, the more deficits it causes in the spatial memory and aggression of rats during adolescence.
Keywords: hypoxia, ischemia, prenatal, spatial memory, aggression
Abstract: Purpose: This study was performed to investigate the influence of α-adrenoceptor subtypes upon ureteral smooth muscle contractile responses. Methods: Rat ureters were challenged in vitro with noradrenaline (NA), the α1-adrenoceptor agonist phenylephrine (PE), and the α2-adrenoceptor agonist clonidine (CLON). The influences of the agonists on the magnitude and frequency of acetylcholine (ACh)-stimulated phasic contractile responses were recorded. Results: The magnitude of the phasic contractile responses effected by ACh was not significantly influenced by the adrenoceptor agonists, but the frequency of the response was significantly enhanced by all three agonists (p < 0.05). Idazoxan and prazosin abolished the rise in frequency effected by CLON and PE, respectively, whereas both antagonists in combination were required to abolish the increase in frequency effected by NA. Conclusions: It has been demonstrated that α1- and α2-adrenoceptors modulate the contractile function of rat ureteral smooth muscle by increasing the frequency, but not the magnitude, of phasic contractile responses. The enhancement of contractile function by NA is mediated by mechanisms dependent upon both α1- and α2-adrenoceptors.
Keywords: acetylcholine, noradrenaline, adrenoceptors, smooth muscle, ureter
Abstract: Background: Exposure to high altitude in hypobaric hypoxia (HH) is considered to be a physiological oxidative/ nitrosative stress. Quercetin (Que) is an effective antioxidant and free radical scavenger against oxidative/nitrosative stress. Aims: The aim of this study was to investigate the cardioprotective effects of Que in animals exposed to intermittent HH (IHH) and therefore exposed to oxidative/nitrosative stress. Materials and methods: Wistar albino male rats were exposed to short-term (2 days) or long-term (4 weeks; 5 days/week) IHH in a hypobaric chamber (5,500 m, 8 h/day, 380 mmHg, 12% O2, and 88% N2). Half of the animals received natural antioxidant Que (body weight: 30 mg/kg) daily before each IHH exposure and the remaining rats received vehicle (carboxymethylcellulose solution). Control rats were kept under normobaric normoxia (Nx) and treated in a corresponding manner. One day after the last exposure to IHH, we measured the cardiac hypoxia-induced oxidative/nitrosative stress biomarkers: the malondialdehyde (MDA) level and protein carbonyl (PC) content, the activity of some antioxidant enzymes [superoxide dismutase (SOD) and catalase (CAT)], the nitrite plus nitrate (NOx) production, and the inducible nitric oxide synthase (iNOS) protein expression. Results: Heart tissue MDA and PC levels, NOx level, and iNOS expression of IHH-exposed rats had increased, and SOD and CAT activities had decreased compared with those of the Nx-exposed rats (control groups). MDA, CP, NOx, and iNOS levels had decreased in Que-treated IHH-exposed rats compared with IHH-exposed rats (control groups). However, Que administration increased SOD and CAT activities of the heart tissue in the IHH-exposed rats. Conclusion: HH exposure increases oxidative/nitrosative stress in heart tissue and Que is an effective cardioprotective agent, which further supports the oxidative cardiac dysfunction induced by hypoxia.
Keywords: cardioprotection, intermittent hypobaric hypoxia, quercetin, oxidative/nitrosative stress, natural antioxidants
Abstract: Autophagy is a lysosome degradation pathway through which damaged organelles and macromolecules are degraded within the cell. A decrease in activity of the autophagic process has been linked to several age-associated pathologies, including triglyceride accumulation, mitochondrial dysfunction, muscle degeneration, and cardiac malfunction. Here, we examined the differences in the autophagic response using autophagy-inducer rapamycin (Rapa) in peripheral blood mononuclear cells (PBMCs) from young (21.8 ± 1.9 years) and old (64.0 ± 3.7 years) individuals. Furthermore, we tested the interplay between the heat shock response and autophagy systems. Our results showed a significant increase in LC3-II protein expression in response to Rapa treatment in young but not in old individuals. This was associated with a decreased response in MAP1LC3B mRNA levels, but not SQSTM1/p62. Furthermore, HSPA1A mRNA was upregulated only in young individuals, despite no differences in HSP70 protein expression. The combined findings suggest a suppressed autophagic response following Rapa treatment in older individuals.
Keywords: autophagy, aging, HSP, PBMC, rapamycin
Abstract: Aims: Right- and left-side-dominant individuals reveal target-matching asymmetries between joints of the dominant and non-dominant upper limbs. However, it is unclear if such asymmetries are also present in lower limb’s joints. We hypothesized that right-side-dominant participants perform knee joint target-matching tasks more accurately with their non-dominant leg compared to left-side-dominant participants. Methods: Participants performed position sense tasks using each leg by moving each limb separately and passively on an isokinetic dynamometer. Results: Sidedominance affected (p < 0.05) knee joint absolute position errors only in the non-dominant leg but not in the dominant leg: right-side-dominant participants produced less absolute position errors (2.82° ± 0.72°) with the non-dominant leg compared to left-side-dominant young participants (3.54° ± 0.33°). Conclusions: In conclusion, right-side-dominant participants tend to perform a target-matching task more accurately with the non-dominant leg compared to left-side-dominant participants. Our results extend the literature by showing that right-hemisphere specialization under proprioceptive target-matching tasks may be not evident at the lower limb joints.
Keywords: handedness, laterality, position sense, knee joint, dynamometer
Abstract: Several Hungarian and foreign researchers have already studied the cardiorespiratory parameters of elite handball players. There are only a few studies though, which would separately review the changes in the functions of different organ systems. The aim of this study is to investigate the effect of an intervention (physical activity) on the cardiorespiratory system. In this study, 16 elite female handball players participated, whose body compositions were measured and took two vita maxima tests. During the analysis, each cardiorespiratory parameter was monitored for every 20 s. Between the two examinations, 6 weeks passed and an intervention took place. There was a significant decrease in relative body fat and a significant increase in relative muscle mass. Remarkable positive changes occurred in the values of ventilation, oxygen pulse, and in both absolute and relative aerobic capacities as well. The mean values of the team developed as expected, but the individual changes in body composition and cardiorespiratory parameters are just as important. First, we chose four players, who had the most outstanding changes. Second, we analyzed such parameters, which were expected to show adequate results in terms of the apparatus(es) functioning.
Keywords: cardiovascular and respiratory parameters, maximal workload, intervention, handball players, aerobic capacity
Abstract: Low-intensity resistance exercise with blood-flow restriction (BFR) promotes similar adaptations to high-intensity resistance exercise (HI-RE). Interestingly, BFR has been demonstrated to be effective for a wide range of occlusion pressures. However, the occlusion pressure magnitude may alter the psychophysiological stress related to BFR as measured by rating of perceived exertion scale (RPE) and rating of pain. We aimed to compare the RPE and pain levels across different magnitudes of occlusion pressures, promoting new knowledge regarding occlusion pressure on stress related to BFR. All BFR protocols ranging between 40% and 80% of total arterial occlusion (BFR40, BFR50, BFR60, BFR70, and BFR80) were compared to HI-RE in 12 participants using a randomized and crossover design 72 h apart. BFR protocols and HI-RE were performed with 30% and 80% of one-repetition maximum (1RM) test value, respectively. RPE and pain levels were measured before exercise and immediately after each set. BFR protocols (i.e., BFR40 and BFR50) presented overall lower RPE response compared to higher-pressure BFR (i.e., BFR70 and BFR80) and HI-RE conditions. For pain levels, low-pressure BFRs (i.e., BFR40 and BFR50), and HI-RE showed lower values than high-pressure BFR protocols (i.e., BFR60, BFR70, and BFR80). In conclusion, low-pressure BFR protocols promote lower RPE and pain compared to high-pressure BFR protocols (between 60% and 80% of occlusion pressure), when total training volume (TTV) is equalized. In addition, HI-RE promotes similar levels of pain, but higher RPE than low-pressure BFR, probably due to the higher TTV.
Keywords: resistance training, blood-flow restriction, psychophysiological stress, rating of perceived exertion, pain