scholarly journals Effects of different dark chocolate diets on memory functions and brain corticosterone levels in rats under chronic stress

2020 ◽  
Vol 24 (3) ◽  
pp. 185-196
Author(s):  
Elham Kalantarzadeh ◽  
◽  
Maryam Radahmadi ◽  
Parham Reisi ◽  
◽  
...  

Introduction: Stress influences cognitive behavior adversely, whereas dark chocolate exhibits positive effects on memory processes. This study investigated the effects of different dark chocolate diets on various aspects of brain functions in rats under chronic stress Methods: Thirty-five rats were randomly allocated into five groups: control, stress, stress with different (compulsory, optional and restricted) dark chocolate diets. Latency, dark stay (DS) time and the number of entrance to the dark compartment were respectively evaluated as memory, memory consolidation and locomotor activity by passive avoidance test. Results: There were significant differences between initial latency and latency after 1 day in all groups. In the stress-compulsory and restricted dark chocolate diet groups, latency after 1 day increased significantly. Moreover, the DS time was not significantly higher in the stressed group than the control group. The DS time and number of entrance to dark compartment decreased significantly in the stress-compulsory dark chocolate diet group compared to the stressed group. Furthermore, the number of entrance to dark compartment was significantly higher for the stress- optional dark chocolate diet compared to those with the compulsory diet. Additionally, serum and hippocampal corticosterone levels, except in the frontal cortex, were significantly lower only in the stress-compulsory dark chocolate diet group compared to the stressed group. Conclusion: Different dark chocolate diets had various effects on brain functions under chronic stress. Respectively, the compulsory and optional dark chocolate diets had the best and least effects on brain function improvement. Only the compulsory dark chocolate diet could improve brain functions such as memory, memory consolidation and locomotor activity.

Author(s):  
Megha Gokul ◽  
Nayanatara Arun Kumar ◽  
Rekha Durgadas Kini ◽  
Vandana Blossom ◽  
Bhagyalakshmi Kodavanji ◽  
...  

Abstract Background In recent years, increased stress in human life has a dual effect on brain and body physiology. Chronic stress takes a toll on physiology as well as on quality of life, ultimately leading to affective disorders. Rodent models are indispensable tools for studying the etiology and progress of depression. C-reactive protein has been proposed as a novel inflammatory marker. Methods Rats were divided into control and experimental stress groups (n = 6 each). The experimental group consisted of rats that were exposed to a set of chronic unpredictable stressors for 15 days. At the end of the 15th day, the animals were anesthetized, and blood samples were collected through cardiac puncture. Then the blood samples were analyzed for selected biochemical and oxidative stress parameters. Results Serum glutamic oxaloacetic transaminase (p < 0.0001), serum glutamic pyruvic transaminase (p < 0.001), serum malondialdehyde (p < 0.0001), total antioxidant level (p < 0.0001), and serum cortisol (p < 0.0001) were significantly increased in the stressed group when compared with the control group. C-reactive protein significantly (p < 0.0001) increased in the stressed group when compared with the control group. Conclusion Our results demonstrate that chronic unpredictable stress ameliorated depression-like behavior, which might have caused the dysregulation of the hypothalamic-pituitary-adrenal axis, causing the imbalance in the biochemical and oxidative parameters increasing the inflammatory markers. The inflammation-induced model of the chronic unpredictable stress model of comorbid depression might provide a variety of new targets for antidepressant therapies.


2018 ◽  
Author(s):  
Benjamin Thürer ◽  
Sarah Gedemer ◽  
Anne Focke ◽  
Thorsten Stein

AbstractPositive effects of variable practice conditions on subsequent motor memory consolidation and generalization are widely accepted and described as the contextual interference effect (CIE). However, the general benefits of CIE are low and these benefits might even depend on decreased retest performances in the blocked-practicing control group, caused by retroactive inhibition. The aim of this study was to investigate if CIE represents a true learning phenomenon or possibly reflects confounding effects of retroactive inhibition. We tested 48 healthy human participants adapting their reaching movements to three different force field magnitudes. Subjects practiced the force fields in either a Blocked (B), Random (R), or Constant (C) schedule. In addition, subjects of the Blocked group performed either a retest schedule that did (Blocked-Matched; BM) or did not (Blocked-Unmatched; BU) control for retroactive inhibition. Results showed that retroactive inhibition did not affect the results of the BU group much and that the Random group showed a better consolidation performance compared to both Blocked groups. However, compared to the Constant group, the Random group showed only slight benefits in its memory consolidation of the mean performance across all force field magnitudes and no benefits in absolute performance values. This indicates that CIE reflects a true motor learning phenomenon, which is independent of retroactive inhibition. However, random practice is not always beneficial over constant practice.


2020 ◽  
Vol 63 (4) ◽  
pp. 1018-1032
Author(s):  
Chia-Hsin Wu ◽  
Roger W. Chan

Purpose Semi-occluded vocal tract (SOVT) exercises with tubes or straws have been widely used for a variety of voice disorders. Yet, the effects of longer periods of SOVT exercises (lasting for weeks) on the aging voice are not well understood. This study investigated the effects of a 6-week straw phonation in water (SPW) exercise program. Method Thirty-seven elderly subjects with self-perceived voice problems were assigned into two groups: (a) SPW exercises with six weekly sessions and home practice (experimental group) and (b) vocal hygiene education (control group). Before and after intervention (2 weeks after the completion of the exercise program), acoustic analysis, auditory–perceptual evaluation, and self-assessment of vocal impairment were conducted. Results Analysis of covariance revealed significant differences between the two groups in smoothed cepstral peak prominence measures, harmonics-to-noise ratio, the auditory–perceptual parameter of breathiness, and Voice Handicap Index-10 scores postintervention. No significant differences between the two groups were found for other measures. Conclusions Our results supported the positive effects of SOVT exercises for the aging voice, with a 6-week SPW exercise program being a clinical option. Future studies should involve long-term follow-up and additional outcome measures to better understand the efficacy of SOVT exercises, particularly SPW exercises, for the aging voice.


2020 ◽  
Vol 23 (5) ◽  
pp. 402-410 ◽  
Author(s):  
Lin-Zi Li ◽  
Shan-Shan Lei ◽  
Bo Li ◽  
Fu-Chen Zhou ◽  
Ye-Hui Chen ◽  
...  

Aim and Objective: The Dendrobium officinalis flower (DOF) is popular in China due to common belief in its anti-aging properties and positive effects on “nourish yin”. However, there have been relatively few confirmatory pharmacological experiments conducted to date. The aim of this work was to evaluate whether DOF has beneficial effects on learning and memory in senescent rats, and, if so, to determine its potential mechanism of effect. Materials and Methods: SD rats were administrated orally DOF at a dose of 1.38, or 0.46 g/kg once a day for 8 weeks. Two other groups included a healthy untreated control group and a senescent control group. During the 7th week, a Morris water maze test was performed to assess learning and memory. At the end of the experiment, serum and brain samples were collected to measure concentrations of antioxidant enzymes, including malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GSH-Px) in serum, and the neurotransmitters, including γ-aminobutyric acid (γ-GABA), Glutamic (Glu), and monoamine oxidase B (MAO-B) in the brain. Histopathology of the hippocampus was assessed using hematoxylin-eosin (H&E) staining. Results: The results suggested that treatment with DOF improved learning as measured by escape latency, total distance, and target quadrant time, and also increased levels of γ-GABA in the brain. In addition, DOF decreased the levels of MDA, Glu, and MAO-B, and improved SOD and GSHPx. Histopathological analysis showed that DOF also significantly reduced structural lesions and neurodegeneration in the hippocampus relative to untreated senescent rats. Conclusion: DOF alleviated brain aging and improved the spatial learning abilities in senescent rats, potentially by attenuating oxidative stress and thus reducing hippocampal damage and balancing the release of neurotransmitters.


2018 ◽  
Author(s):  
Franziska Lautenbach

BACKGROUND Dealing with stress is of central importance. Lately, smartphone applications (apps) are deployed in stress interventions as they offer maximal flexibility for users. First results of experimental studies show that anti-stress apps effect subjective perception of stress positively (Ly et al., 2014). However, current literature lacks studies on physiological stress reactions (e.g., cortisol), although they are of special interest to health issues. OBJECTIVE Therefore, the aim of this study was to investigate the effectiveness of an anti-stress app in chronic and acute stress reduction on a physiological (cortisol) and psychological level (subjective perception of stress) in comparison to a face-to-face and a control group in a pre-post design, for the first time. METHODS Sixty-two participants took part in the pretesting procedure (drop-out of 53 %). Based on age, gender, physical activity and subjectively perceived acute stress due to the Trier Social Stress Test for groups (TSST-G; von Dawans et al., 2011) as well as based on subjectively chronic stress assessed during the pretest, participants were parallelized in three groups (anti-stress-app: n = 10, face-to-face: n = 11, control group: n = 9). RESULTS After six weeks of the cognitive-based resource-oriented intervention, participants were exposed to the TSST-G for post testing. Results did not show a change of cortisol secretion or cognitive appraisal of the acute stressor. Further, no changes were detected in the chronic physiological stress reaction. CONCLUSIONS Possible causes are discussed extensively. CLINICALTRIAL no


2020 ◽  
Vol 10 (12) ◽  
pp. 350
Author(s):  
Ana María Díez-Pascual ◽  
María Pilar García García Díaz

The use of information and communication technologies (ICTs) has become a fundamental tool in all areas of today’s society, including higher education. Lessons cannot be envisaged without the use of tools such as computers, tablets or mobile devices. Many lecturers use audience response systems (ARS) to keep their classes engaged. ARS software allows teachers to interact with students via polls, text responses, or multiple-choice questions displayed via their mobile devices. A new example of the use of this type of devices in education is gamification, a technique that uses a set of activities with ludic character as a learning methodology in order to facilitate the acquisition of knowledge and competences. One of the most used gamification tools is Kahoot!, a free learning application based on a mixture of game and creativity, which encourages attention and participation of students through questions and answers formulated by the teacher and designed in a way that students respond via their mobile phones. This paper examines the use of Kahoot! in a subject belonging to the chemistry area. In order to assess the benefits of this tool, it was tested in a group of students to review the knowledge and skills acquired during the theoretical lessons prior to the exams, and the academic results were compared with those of a control group of students who did not use the tool. The results demonstrate that the use of Kahoot! led to an improvement in the teaching–learning process of the students and a noteworthy rise in their marks, and that its positive effects rise with increasing the frequency of use of this didactic tool.


2021 ◽  
pp. 009164712110115
Author(s):  
Charissa H. W. Wong ◽  
Li Neng Lee ◽  
Alberto Pérez Pereiro

Short-term Christian overseas volunteer trips, also known as short-term mission trips (STMs), have become increasingly prevalent (Howell & Dorr, 2007). However, research on these programs has been limited. This quasi-experimental study adds to the literature by quantitatively measuring the effects of an STM from Singapore to Thailand. STM recipients’ ( n = 44) self-esteem and readiness for self-directed learning (RSDL) were compared across timepoints – pre-test, post-test, follow-up – and with a control group ( n = 50). It was hypothesized that recipients would experience an increase in self-esteem and RSDL such that their scores would be higher than the control group post-STM. Results provide partial support for the hypotheses; while improvements among recipients were either not significant (for self-esteem) or not long-lasting (for RSDL), recipients had higher scores than the control group post-STM. This suggests that STMs have some, albeit limited, positive effects. Recommendations for promoting greater and longer-lasting effects are offered.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Huiyun Wang ◽  
Chengcheng Li ◽  
Meng Peng ◽  
Lei Wang ◽  
Di Zhao ◽  
...  

Abstractβ-Conglycinin (β-CG), an anti-nutritional factor, is a major allergen in soybeans to induce intestinal dysfunction and diarrhea in neonatal animals, including piglets and human infants. This study with a piglet model determined the effects of N-acetylcysteine (NAC) on intestinal function and autophagy in response to β-CG challenge. Twenty-four 12-day-old piglets (3.44 ± 0.28 kg), which had been weaned at 7 days of age and adapted for 5 days after weaning, were randomly allocated to the control, β-CG, and β-CG + NAC groups. Piglets in the control group were fed a liquid diet containing 10% casein, whereas those in the β-CG and β-CG + NAC groups were fed the basal liquid diets containing 9.5% casein and 0.5% β-CG for 2 days. Thereafter, pigs in the β-CG + NAC group were orally administrated with 50 mg (kg BW)−1 NAC for 3 days, while pigs in the other two groups were orally administrated with the same volume of sterile saline. NAC numerically reduced diarrhea incidence (− 46.2%) and the concentrations of hydrogen peroxide and malondialdehyde, but increased claudin-1 and intestinal fatty-acid binding protein (iFABP) protein abundances and activities of catalase and glutathione peroxidase in the jejunum of β-CG-challenged piglets. Although β-CG challenge decreased the villus height, villus height/crypt depth ratio, and mRNA levels of claudin-1 and occludin, no significant differences were observed in these indices between the control and β-CG + NAC groups, suggesting the positive effects of NAC supplementation on intestinal mucosal barrier function. Moreover, NAC increased the concentrations of citrulline and D-xylose in the plasma, as well as the expression of genes for aquaporin (AQP) 3, AQP4, peptide transporter 1 (PepT1), sodium/glucose co-transporter-1 (SGLT-1), potassium inwardly-rectifying channel, subfamily J, member 13 (KCNJ13), and solute carrier family 1 member 1 (SLC1A1) in the jejunum, demonstrating that NAC augmented intestinal metabolic activity and absorptive function. Remarkably, NAC decreased Atg5 protein abundance and the LC3II/LC3I ratio (an indicator of autophagy) in the jejunum of β-CG-challenged piglets. Taken together, NAC supplementation improved intestinal function and attenuated intestinal autophagy in β-CG-challenged piglets.


Author(s):  
Niklas Sörlén ◽  
Andreas Hult ◽  
Peter Nordström ◽  
Anna Nordström ◽  
Jonas Johansson

Abstract Background We aimed to determine the effectiveness of 4 weeks of balance exercise compared with no intervention on objectively measured postural sway. Methods This was a single-center parallel randomized controlled, open label, trial. A six-sided dice was used for allocation at a 1:1-ratio between exercise and control. The trial was performed at a university hospital clinic in Sweden and recruited community-dwelling older adults with documented postural instability. The intervention consisted of progressively challenging balance exercise three times per week, during 4 weeks, with follow-up at week five. Main outcome measures were objective postural sway length during eyes open and eyes closed conditions. Results Sixty-five participants aged 70 years (balance exercise n = 32; no intervention n = 33) were randomized. 14 participants were excluded from analysis because of early dropout before follow-up at week five, leaving 51 (n = 22; n = 29) participants for analysis. No significant differences were detected between the groups in any of the postural sway outcomes. Within-group analyses showed significant improvements in hand grip strength for the intervention group, while Timed Up & Go improvements were comparable between groups but only statistically significant in the control group. Conclusions Performing balance exercise over a four-week intervention period did not acutely improve postural sway in balance-deficient older adults. The lower limit in duration and frequency to achieve positive effects remains unclear. Trial registration Clinical trials NCT03227666, July 24, 2017, retrospectively registered.


Author(s):  
José Antonio Mingorance ◽  
Pedro Montoya ◽  
José García Vivas Miranda ◽  
Inmaculada Riquelme

Whole body vibration has been proven to improve the health status of patients with fibromyalgia, providing an activation of the neuromuscular spindles, which are responsible for muscle contraction. The present study aimed to compare the effectiveness of two types of whole body vibrating platforms (vertical and rotational) during a 12-week training program. Sixty fibromyalgia patients (90% were women) were randomly assigned to one of the following groups: group A (n = 20), who performed the vibration training with a vertical platform; group B (n = 20), who did rotational platform training; or a control group C (n = 20), who did not do any training. Sensitivity measures (pressure pain and vibration thresholds), quality of life (Quality of Life Index), motor function tasks (Berg Scale, six-minute walking test, isometric back muscle strength), and static and dynamic balance (Romberg test and gait analysis) were assessed before, immediately after, and three months after the therapy program. Although both types of vibration appeared to have beneficial effects with respect to the control group, the training was more effective with the rotational than with vertical platform in some parameters, such as vibration thresholds (p < 0.001), motor function tasks (p < 0.001), mediolateral sway (p < 0.001), and gait speed (p < 0.05). Nevertheless, improvements disappeared in the follow-up in both types of vibration. Our study points out greater benefits with the use of rotational rather than vertical whole body vibration. The use of the rotational modality is recommended in the standard therapy program for patients with fibromyalgia. Due to the fact that the positive effects of both types of vibration disappeared during the follow-up, continuous or intermittent use is recommended.


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