scholarly journals Effect of Short- and Long-term Melatonin Treatments on the Reproductive Activity of the Tropical Damselfish Chrysiptera Cyanea

2021 ◽  
Author(s):  
Satoshi Imamura ◽  
Sung-Pyo Hur ◽  
Yuki Takeuchi ◽  
Md. Badruzzaman ◽  
Angka Mahardini ◽  
...  
Keyword(s):  
Reproductive Activity ◽  
Melatonin Treatment ◽  
Hpg Axis ◽  
Transcript Levels ◽  
Hormone Synthesis ◽  
Negative Effect ◽  
Short And Long Term ◽  
The Brain ◽  
Long Photoperiod

Abstract Photoperiod plays a role in controlling the initiation and termination of reproduction in fish. Melatonin is an internal transducer of environmental photoperiod and is involved in regulating reproduction. The present study aimed to examine how melatonin impacts the transcript levels of kisspeptin ( kiss1 and kiss2 ), gonadotropin-releasing hormones ( gnrh1 ), and the β -subunit of gonadotropins ( fshβ and lhβ ) in the brain of the sapphire devil, a tropical damselfish with long photoperiod preference. Feeding mature females with melatonin-containing pellets inhibited increases in the transcript levels of kiss1 , gnrh1 , and lhβ within 3 h. Continuous melatonin treatment for 1 week resulted in oocyte regression and downregulation of kiss2 , gnrh1 , fshβ , and lhβ . When the transcript levels of kiss1 and gnrh1 were measured at 4-h intervals in the brain of sapphire devil, a day–low/night–high fluctuation was observed. The hypothalamic– pituitary–gonadal (HPG) axis may be influenced by melatonin, exerting a negative effect at night because the transcript levels of aralkylamine N -acetyltransferase ( aanat2 ) increased during the scotophase. The expression of aanat2 was higher under short-day than long-day conditions, suggesting that there is a seasonal change in melatonin levels at night. It was concluded that change in photoperiod becomes a proximal factor for controlling the hormone synthesis in the HPG axis through melatonin.

The effect of L-carnitine depletion induced by long-term therapy of mice with meldonium on brain mitochondrial balance

2021 ◽  
Vol 67 (1) ◽  
pp. 74-80
Author(s):  
E.A. Shaforostova ◽  
A.P. Gureev ◽  
I.Yu. Vitkalova ◽  
V.N. Popov
Keyword(s):  
Mitochondrial Biogenesis ◽  
Term Therapy ◽  
Brain Cells ◽  
Oxygen Species ◽  
Mitochondrial Potential ◽  
Metabolic Drug ◽  
Negative Effect ◽  
Long Term Therapy ◽  
The Brain

Meldonium is a metabolic drug used for treatment of coronary heart disease. The effect of the drug lies in its ability to inhibit synthesis and transport of L-carnitine. At the same time, a long-term deficiency of L-carnitine can theoretically negatively affect the activity of the transcription factor Nrf2, which is extremely important for maintaining mitochondrial balance in cells. We have shown that meldonium therapy for 3 months at a dose of 100 mg/kg in mice causes a decrease in the expression of the Nrf2 gene in the brain. A decrease in the Nrf2 level causes suppression of mitochondrial biogenesis, which is manifested in a decrease in the level of mtDNA and the level of Cox1 expression. However, no negative effect of meldonium on the bioenergetics parameters of mitochondria was found, as evidenced by the maintenance of a stable mitochondrial potential and the level of production of reactive oxygen species. Jne mohth after the end of the meldonium therapy, expression of the genes responsible for mitochondrial biogenesis and mitophagy (p62, Pink1, Tfam) was observed and the expression level of genes responsible for mitochondrial fusion returned to control values. These changes may be associated with the normalization of the level of L-carnitine in brain cells.

scholarly journals Rosuvastatin revert memory impairment and anxiogenic-like effect in mice infected with the chronic ME-49 strain of Toxoplasma gondii

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0250079
Author(s):  
Fernanda Ferreira Evangelista ◽  
Willian Costa-Ferreira ◽  
Francini Martini Mantelo ◽  
Lucimara Fátima Beletini ◽  
Amanda Hinobu de Souza ◽  
...  
Keyword(s):  
Toxoplasma Gondii ◽  
Memory Impairment ◽  
Brain Inflammation ◽  
Long Term Memory ◽  
Histopathological Analysis ◽  
Term Memory ◽  
Anxiogenic Effect ◽  
Short And Long Term ◽  
The Brain

The aim of this study was to investigate the effect of rosuvastatin treatment on memory impairment, and anxiogenic-like effects in mice chronically infected with Toxoplasma gondii. For this, Balb/c mice were infected orally with chronic ME-49 strain of Toxoplasma gondii. Oral treatment with rosuvastatin (40mg/kg/day) started on the 51st day post-infection and was performed daily for 21 days. After completion of treatment, anxiety-like effects and locomotion were investigated in the open field (OF) test, whereas novel object recognition (NOR) test was used for evaluation of short- and long-term memory. At the end of the experiments, the brain was collected for Toxoplasma gondii DNA quantification and histopathological analysis. Infection with ME-49 strain decreased the time spent in the center of OF, indicating an anxiogenic effect, without affecting total and peripheral locomotion. Rosuvastatin treatment inhibited the change in the center time. Besides, pharmacological treatment increased total and central locomotion in both non-infected and infected animals. Infection also impaired both short- and long-term memory in the NOR test, and these effects were reverted by rosuvastatin treatment. In addition to effects in behavioral changes, rosuvastatin also reduced parasite load in the brain and attenuated signs of brain inflammation such as perivascular cuffs, inflammatory cell infiltration and tissue damage. These findings indicate for the first time the efficacy of rosuvastatin in treatment of memory impairment and anxiogenic effect evoked by infection with Toxoplasma gondii. These effects might be mediated by reduced cyst load, which in turn decrease inflammation and damage in the brain.

scholarly journals ANALYSIS OF ECONOMIC ON ENVIRONMENTAL DEGRADATION IN INDONESIA

2021 ◽  
pp. 251
Author(s):  
Rahardyan Haris Yuswinarto ◽  
Edy Yusuf Agung Gunanto
Keyword(s):  
Economic Growth ◽  
Population Growth ◽  
Environmental Degradation ◽  
Short Term ◽  
Gas Emissions ◽  
Co2 Gas ◽  
Negative Effect ◽  
Short And Long Term ◽  
Dynamic Time

Environmental degradation occurs is influenced by economic growth and the means of transportation that support it, besides that, the population size also affects the occurrence of environmental degradation. This study aims to determine the effect of economic growth, population growth and total of transportation on environmental degradation in short and long term. This research uses dynamic time series autoregressive distribution lag method. The results showed that the gross domestic product (GDP) variable had a significant positive effect in increasing CO2 gas emissions both in the short and long term. The variable amount of transportation has a positive and insignificant effect on the increase in CO2 gas emissions in the short term and has a negative effect in the long term. Meanwhile, population growth variable has a positive and significant effect in the short term and negative and significant in the long term.

scholarly journals The New Wave of Currency Devaluations in Africa – Will the Devalued Birr Help the Coffee Exports?

2019 ◽  
Vol 12 (4.) ◽  
pp. 101-118
Author(s):  
Szabolcs Pasztor
Keyword(s):  
Developing Countries ◽  
Current Account Deficit ◽  
Balance Of Payments ◽  
New Wave ◽  
Long Run ◽  
Negative Effect ◽  
Short And Long Term ◽  
Coffee Sector ◽  
The Impact

Despite the fact that currency devaluations are likely to have a negative effect on the economy in the long run, Ethiopia devalued its national currency, the birr (ETB), by 15 percent in 2017. They turned to this option in the hope of attracting more investments from abroad, decreasing import bills, improving the current account deficit and giving a boost to the exports of the coffee sector. A couple of months later, the impact seems to be promising because the export has been revived in some areas. However, it has to be stressed that the imported commodities may experience a price increase, there can be a widening balance of payments deficit and rising inflation. The paper aims to shed more light on the short- and long-term impacts of currency devaluations in the developing countries with a special emphasis on Ethiopia. Also, the recent Ethiopian measure is to be analyzed in greater detail highlighting the impacts on export earnings, import bills, the balance of payments, and on the overall competitiveness of the coffee sector.

Short- and Long-Term Changes in Joint Co-Contraction Associated With Motor Learning as Revealed From Surface EMG

2002 ◽  
Vol 88 (2) ◽  
pp. 991-1004 ◽  
Author(s):  
Rieko Osu ◽  
David W. Franklin ◽  
Hiroko Kato ◽  
Hiroaki Gomi ◽  
Kazuhisa Domen ◽  
...  
Keyword(s):  
Surface Emg ◽  
Internal Models ◽  
Series Data ◽  
Time Step ◽  
Cross Correlation Analysis ◽  
Performance Error ◽  
Short And Long Term ◽  
And Performance ◽  
The Brain

In the field of motor control, two hypotheses have been controversial: whether the brain acquires internal models that generate accurate motor commands, or whether the brain avoids this by using the viscoelasticity of musculoskeletal system. Recent observations on relatively low stiffness during trained movements support the existence of internal models. However, no study has revealed the decrease in viscoelasticity associated with learning that would imply improvement of internal models as well as synergy between the two hypothetical mechanisms. Previously observed decreases in electromyogram (EMG) might have other explanations, such as trajectory modifications that reduce joint torques. To circumvent such complications, we required strict trajectory control and examined only successful trials having identical trajectory and torque profiles. Subjects were asked to perform a hand movement in unison with a target moving along a specified and unusual trajectory, with shoulder and elbow in the horizontal plane at the shoulder level. To evaluate joint viscoelasticity during the learning of this movement, we proposed an index of muscle co-contraction around the joint (IMCJ). The IMCJ was defined as the summation of the absolute values of antagonistic muscle torques around the joint and computed from the linear relation between surface EMG and joint torque. The IMCJ during isometric contraction, as well as during movements, was confirmed to correlate well with joint stiffness estimated using the conventional method, i.e., applying mechanical perturbations. Accordingly, the IMCJ during the learning of the movement was computed for each joint of each trial using estimated EMG-torque relationship. At the same time, the performance error for each trial was specified as the root mean square of the distance between the target and hand at each time step over the entire trajectory. The time-series data of IMCJ and performance error were decomposed into long-term components that showed decreases in IMCJ in accordance with learning with little change in the trajectory and short-term interactions between the IMCJ and performance error. A cross-correlation analysis and impulse responses both suggested that higher IMCJs follow poor performances, and lower IMCJs follow good performances within a few successive trials. Our results support the hypothesis that viscoelasticity contributes more when internal models are inaccurate, while internal models contribute more after the completion of learning. It is demonstrated that the CNS regulates viscoelasticity on a short- and long-term basis depending on performance error and finally acquires smooth and accurate movements while maintaining stability during the entire learning process.

scholarly journals Brain imaging and human nutrition: which measures to use in intervention studies?

2013 ◽  
Vol 110 (S1) ◽  
pp. S1-S30 ◽  
Author(s):  
Stéphane V. Sizonenko ◽  
Claudio Babiloni ◽  
Eveline A. de Bruin ◽  
Elizabeth B. Isaacs ◽  
Lena S. Jönsson ◽  
...  
Keyword(s):  
Brain Imaging ◽  
Intervention Studies ◽  
Resonance Spectroscopy ◽  
Nutritional Interventions ◽  
Imaging Technologies ◽  
Short And Long Term ◽  
Imaging Markers ◽  
Nutritional Studies ◽  
The Brain

The present review describes brain imaging technologies that can be used to assess the effects of nutritional interventions in human subjects. Specifically, we summarise the biological relevance of their outcome measures, practical use and feasibility, and recommended use in short- and long-term nutritional studies. The brain imaging technologies described consist of MRI, including diffusion tensor imaging, magnetic resonance spectroscopy and functional MRI, as well as electroencephalography/magnetoencephalography, near-IR spectroscopy, positron emission tomography and single-photon emission computerised tomography. In nutritional interventions and across the lifespan, brain imaging can detect macro- and microstructural, functional, electrophysiological and metabolic changes linked to broader functional outcomes, such as cognition. Imaging markers can be considered as specific for one or several brain processes and as surrogate instrumental endpoints that may provide sensitive measures of short- and long-term effects. For the majority of imaging measures, little information is available regarding their correlation with functional endpoints in healthy subjects; therefore, imaging markers generally cannot replace clinical endpoints that reflect the overall capacity of the brain to behaviourally respond to specific situations and stimuli. The principal added value of brain imaging measures for human nutritional intervention studies is their ability to provide uniquein vivoinformation on the working mechanism of an intervention in hypothesis-driven research. Selection of brain imaging techniques and target markers within a given technique should mainly depend on the hypothesis regarding the mechanism of action of the intervention, level (structural, metabolic or functional) and anticipated timescale of the intervention's effects, target population, availability and costs of the techniques.

Nutritional and environmental effects on reproduction in small ruminants

2004 ◽  
Vol 16 (4) ◽  
pp. 491 ◽  
Author(s):  
G. B. Martin ◽  
J. Rodger ◽  
D. Blache
Keyword(s):  
Small Ruminants ◽  
Cellular Biology ◽  
Cellular Processes ◽  
Physiological Processes ◽  
Reproductive Axis ◽  
Wide Range ◽  
Short And Long Term ◽  
The Impact ◽  
The Brain

Animals live in environments that are both complex and continually changing, so they have to respond to short- and long-term variations in a wide range of factors, such as photoperiod, nutrition and sociosexual signals. Before they were domesticated, animals developed reproductive strategies that coped with these changes and often took advantage of them. The physiological processes that implement these strategies have been modified to some extent during several millennia of controlled breeding, but most persist. Thus, many genotypes still exhibit profound responses to external inputs, such as the induction of ovulation by sociosexual signals and the doubling of litter size by a change in nutrition. The complexity in these responses is now becoming clearer. For example, with sociosexual signals, we now need to consider the stimulatory effects of males on females, of females on males and of females on females. Similarly, the impact of nutrition has been extended beyond the control of puberty and the production of gametes to include phenomena such as ‘fetal programming’, with its potentially profound effects on the life-long performance of the animals. Fortunately, our capacity to research these phenomena has been greatly enhanced by technical improvements in hormone assays, molecular and cellular biology, and real-time ultrasound. This has brought us a better understanding of several of the environmental influences on reproduction, including: the cellular processes within ovarian follicles that mediate the effect of nutrition on ovulation rate; the neuroendocrine pathways through which nutritional inputs affect the brain centres that control appetite and reproduction; and the intracerebral pathways through which sociosexual signals (olfactory and non-olfactory) stimulate the reproductive axis. Importantly, we are now beginning to realise that, as well as considering interactions between environmental inputs and genotype, we need to take into account interactions between the environmental factors themselves, just as the animals do. We still have a long way to go for a complete understanding, but we are nevertheless in a position where we can begin to use this information to develop new management systems for our animals to improve their productivity.

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