Intragastric administration of AMG517, a TRPV1 antagonist, enhanced activity-dependent energy metabolism via capsaicin-sensitive sensory nerves in mice

2020 ◽  
Vol 84 (10) ◽  
pp. 2121-2127
Author(s):  
Jun Hai ◽  
Fuminori Kawabata ◽  
Kunitoshi Uchida ◽  
Shotaro Nishimura ◽  
Shoji Tabata
2019 ◽  
Vol 121 (4) ◽  
pp. 1535-1542 ◽  
Author(s):  
Prajwal P. Thakre ◽  
Mark C. Bellingham

The effect of capsaicin on glycinergic synaptic transmission to juvenile rat hypoglossal motor neurons in acute brainstem slices was evaluated in the presence of TTX. Capsaicin caused a robust decrease in miniature IPSC frequency, amplitude, and half-width, showing that this effect is independent of action potential generation. In the presence of capsazepine, a classic TRPV1 antagonist, capsaicin was still able to reduce spontaneous inhibitory postsynaptic current (IPSC) amplitude and frequency. We further investigated whether the effect of capsaicin on glycinergic transmission to hypoglossal motor neurons is pre- or postsynaptic in nature by recording pairs of evoked IPSCs. Interestingly, capsaicin also reduced evoked IPSC amplitude without affecting paired-pulse ratio, indicating a postsynaptic mechanism of action. Significant reduction was also observed in evoked IPSC half-width, rise time, and decay tau. We also show that capsaicin does not have any effect on either transient (It) or sustained (Is) potassium currents. Finally, we also show that the hyperpolarization-activated cationic current (Ih) also remains unchanged after capsaicin application. NEW & NOTEWORTHY Capsaicin reduces the amplitude of quantal and evoked glycinergic inhibitory neurotransmission to brainstem motor neurons without altering activity-dependent transmitter release. This effect of capsaicin is not due to activation of TRPV1 receptors, as it is not blocked by capsazepine, a TRPV1 receptor antagonist. Capsaicin does not alter voltage-dependent potassium current or the hyperpolarization-activated cationic current in brainstem motor neurons.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Helen Gooch ◽  
Xiaoying Cui ◽  
Victor Anggono ◽  
Maciej Trzaskowski ◽  
Men Chee Tan ◽  
...  

Abstract Schizophrenia has been associated with a range of genetic and environmental risk factors. Here we explored a link between two risk factors that converge on a shared neurobiological pathway. Recent genome-wide association studies (GWAS) have identified risk variants in genes that code for L-type voltage-gated calcium channels (L-VGCCs), while epidemiological studies have found an increased risk of schizophrenia in those with neonatal vitamin D deficiency. The active form of vitamin D (1,25(OH)2D) is a secosteroid that rapidly modulates L-VGCCs via non-genomic mechanisms in a range of peripheral tissues, though its non-genomic effects within the brain remain largely unexplored. Here we used calcium imaging, electrophysiology and molecular biology to determine whether 1,25(OH)2D non-genomically modulated L-VGCCs in the developing prefrontal cortex, a region widely implicated in schizophrenia pathophysiology. Wide-field Ca2+ imaging revealed that physiological concentrations of 1,25(OH)2D rapidly enhanced activity-dependent somatic Ca2+ levels in a small subset of neurons in the developing PFC, termed vitamin D-responsive neurons (VDRNs). Somatic nucleated patch recordings revealed a rapid, 1,25(OH)2D-evoked increase in high-voltage-activated (HVA) Ca2+ currents. Enhanced activity-dependent Ca2+ levels were mediated by L-VGCC but not associated with any changes to Cacna1c (L-VGCC pore-forming subunit) mRNA expression. Since L-VGCC activity is critical to healthy neurodevelopment, these data suggest that suboptimal concentrations of 1,25(OH)2D could alter brain maturation through modulation of L-VGCC signalling and as such may provide a parsimonious link between epidemiologic and genetic risk factors for schizophrenia.


Pathologia ◽  
2021 ◽  
Vol 18 (1) ◽  
pp. 26-32
Author(s):  
I. F. Bielenichev ◽  
A. A. Yehorov

Aim. To establish the effect of the glycine and thiotriazoline (4:1) combination on the parameters of the energy production of the mitochondria of the rat brain under the conditions of simulating an acute cerebrovascular accident. Materials and methods. The experimental part was performed on 90 male Wistar rats weighing 180–200 g. To model acute cerebrovascular accident (ACVA) by ischemic type, a classical model was used, where common carotid arteries had been ligated bilaterally. All animals were divided into 5 experimental groups: the first – intact (sham-operated rats, which during anesthesia had their common carotid arteries separated without ligation); the second – rats with ACVA (control); the third – rats with ACVA, which underwent intragastric administration of glycine at a dose of 200 mg/kg in the form of a tablet mass every day for 4 days; the fourth – rats with stroke, which every day for 4 days underwent intragastric administration of a combination of glycine and thiotriazoline (4:1) in the form of a tablet mass; the fifth – rats with ACVA, which underwent every day intragastric administration of piracetam in the form of a tablet mass at a dose of 500 mg/kg. The sampling of biological material (brain) for research was carried out on the fourth day of the experiment according to the standard method. The mitochondrial fraction was isolated by differential centrifugation in a refrigerated centrifuge. The manifestations of mitochondrial dysfunction, have been spectrophotometrically studied according to the degree of opening of the mitochondrial pore (MP) and mitochondrial transmembrane potential (Ψ). The assessment of the intensity of oxidative stress was determined by the markers of protein oxidative modification – aldehydephenylhydrazone (APH) and ketonedinitrophenylhydrazone (KPH) – spectrophotometrically. The state of energy metabolism was determined by the level of the most significant intermediates – ATP, lactate, succinate and malate. Results. In the group of animals with ACVA modeling, we noted a decrease in the level of ATP in mitochondria by 1.55 times, an increase in lactate content by 1.1 times, a decrease in SDH activity by 3.8 times and a decrease in succinate concentration by 1.1 times relative to the corresponding data of intact groups. Administration of a combination of glycine and thiotriazoline to experimental animals on the fourth day of ACVA modeling led to a 1.9-fold decrease in the opening of the mitochondrial pore and an increase in the charge of the inner mitochondrial membrane by 1.2 times, an increase in ATP in the mitochondrial fraction by 1.1 times, an increase in SDH activity by 3 times, and the activity of NAD-MDH – by 3.7 times, against the background of a decrease in the level of APH by 76.6 % and KPH by 80.7 %, relative to the group of animals with modeling of stroke by ischemic type. Conclusions. Modeling of ACVA leads to the initiation of oxidative stress and the development of an imbalance of energy metabolism intermediates in the brain mitochondria of experimental animals. Administration of a combination of glycine and thiotriazoline leads to a decrease in oxidative damage to mitochondria, increases the production of ATP due to the activation of compensatory mitochondrial-cytosolic shunts, mainly in malate-aspartate and succinate oxidase. In terms of the degree of influence on the indicators of energy metabolism, the combination of glycine and thiotriazoline reliably exceeds the similar actions of glycine and the reference drug - piracetam.


Glia ◽  
2007 ◽  
Vol 55 (12) ◽  
pp. 1251-1262 ◽  
Author(s):  
Luc Pellerin ◽  
Anne-Karine Bouzier-Sore ◽  
Agnès Aubert ◽  
Sébastien Serres ◽  
Michel Merle ◽  
...  

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Qi-da He ◽  
Yuan-peng Huang ◽  
Li-bing Zhu ◽  
Jia-cheng Shen ◽  
Lin-yu Lian ◽  
...  

Acupuncture and moxibustion proved to be very effective in chronic atrophic gastritis (CAG). According to the Chinese traditional medicine theory, chronic diseases have an influence on the function of liver and kidney. However, there is little research to demonstrate this theory. This study is aimed at assessing the1H NMR-based metabolic profiling in liver and kidney of CAG rats and comparing the difference between electroacupuncture and moxibustion treatment. Male SD rats were subjected to CAG modeling by intragastric administration of mixture of 2% sodium salicylate and 30% alcohol coupled with compulsive sporting and irregular fasting for 12 weeks and then treated by electroacupuncture or moxibustion at Liangmen (ST 21) and Zusanli (ST 36) acupoints for 2 weeks. A1H NMR analysis of liver and kidney samples along with histopathological examination and molecular biological assay was employed to assess and compare the therapeutic effects of electroacupuncture and moxibustion. CAG brought characterization of metabolomic signatures in liver and kidney of rats. Both electroacupuncture and moxibustion treatment were found to normalize the CAG-induced changes by restoring energy metabolism, neurotransmitter metabolism, antioxidation metabolism, and other metabolism, while the moxibustion treatment reversed more metabolites related to energy metabolism in liver than electroacupuncture treatment. CAG did have influence on liver and kidney of rats. Both of these treatments had good effects on CAG by reversing the CAG-induced perturbation in liver and kidney. For regulating the energy metabolism in liver, the moxibustion played more important role than electroacupuncture treatment.


1994 ◽  
Vol 22 (3) ◽  
pp. 165-170
Author(s):  
T Hirano

When rats were given a supramaximal dose of caerulein (infused intravenously at 5 μg/kg.h for 4 h) they developed acute pancreatitis characterized by significantly raised amylase levels in the blood. In this model of acute pancreatitis, reduced gastric adenylate energy charge levels were observed, and the leakage of the lysosomal enzyme, cathepsin B, from gastric lysosomes and of the mitochondrial enzyme, malate dehydrogenase, from gastric mitochondria were both significantly accelerated compared with the control group. The intragastric administration of the anti-ulcer agent, teprenone, at a dose of 5 mg/kg (twice before caerulein infusion) significantly inhibited this gastric damage accompanying acute pancreatitis. These results suggest that gastric subcellular organelle fragility may play an important role in the pathogenesis of impaired gastric energy metabolism accompanying acute pancreatitis, and indicate the possible usefulness of teprenone in preventing this gastric damage.


1980 ◽  
Vol 34 (1) ◽  
pp. 213-215 ◽  
Author(s):  
Marina Mata ◽  
David J. Fink ◽  
Harold Gainer ◽  
Carolyn B. Smith ◽  
Leslie Davidsen ◽  
...  

Author(s):  
Ainiwaer Talifu ◽  
Rapkat Samat ◽  
Yilifanjinag Kuerban ◽  
Mamatali Kader ◽  
Dilnur Tursun

Objective: To investigate the effects of five Uygur medicine maturants on the related factors of liver energy metabolism in rats. Methods: After 30 days of preparation and intragastric administration, the weight changes of rats were observed. Enzyme-linked immunosorbent assay (ELISA) was used to detect Na[Formula: see text] K[Formula: see text] ATPase, Ca2[Formula: see text] Mg2[Formula: see text] ATPase and succinate dehydrogenase (SDH) activities; hepatic glycogen (HG) and muscle glycogen (MG) content, plasma triiodothyronine (T3), tetraiodothyronine (T4), and thyrotropin (TSH) content were detected. Results: The Kan (blood) quality regulator reduced the weight of rats, the Sapra regulator increased the weight of rats, the Savda maturant group, and the Balham maturant group increased the Na[Formula: see text] K[Formula: see text] ATPase, Ca2[Formula: see text] Mg2[Formula: see text] ATP, SDH activity, HG, MG, T3, T4, and TSH content of rats significantly, while the other groups had no significant effect on the energy metabolism-related factors. Conclusion: Five kinds of Uygur medicine maturants have effects on the related factors of energy metabolism in the liver of normal rats, and their elevation of serum thyroxine level is related, among which the effects of the Savda maturant group and the Balham maturant group are more significant.


eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Andrea Trevisiol ◽  
Aiman S Saab ◽  
Ulrike Winkler ◽  
Grit Marx ◽  
Hiromi Imamura ◽  
...  

In several neurodegenerative diseases and myelin disorders, the degeneration profiles of myelinated axons are compatible with underlying energy deficits. However, it is presently impossible to measure selectively axonal ATP levels in the electrically active nervous system. We combined transgenic expression of an ATP-sensor in neurons of mice with confocal FRET imaging and electrophysiological recordings of acutely isolated optic nerves. This allowed us to monitor dynamic changes and activity-dependent axonal ATP homeostasis at the cellular level and in real time. We find that changes in ATP levels correlate well with compound action potentials. However, this correlation is disrupted when metabolism of lactate is inhibited, suggesting that axonal glycolysis products are not sufficient to maintain mitochondrial energy metabolism of electrically active axons. The combined monitoring of cellular ATP and electrical activity is a novel tool to study neuronal and glial energy metabolism in normal physiology and in models of neurodegenerative disorders.


2021 ◽  
Author(s):  
Yiming Bai ◽  
Takashi Suzuki

Activity-dependent synaptic plasticity is crucial for responses to the environment. Although the plasticity mechanisms of presynaptic photoreceptor neurons in the Drosophila visual system have been well studied, postsynaptic modifications remain elusive. In addition, further studies on the adaption of the visual system to different light experiences at a circuitry scale are required. Using the modified transcriptional reporter of intracellular Ca2+ method, we describe a way to visualize circuitry changes according to different light experiences. We found enhanced postsynaptic neuronal activity responses in lamina monopolar neuron L2 after prolonged light treatment. Although L1 also has connections with photoreceptors, there were no enhanced activity responses in L1. We also report in this study that activity-dependent transcriptional downregulation of inhibitory histamine receptors (HRs) occurs in postsynaptic neuron L2, but not in L1, during continuous light conditions. We expressed exogenous HR proteins in L2 neurons and found that it attenuated the enhanced activity response caused by constant light exposure. These findings, together with the fact that histamine is the main inhibitory neurotransmitter released by photoreceptors in the Drosophila visual system, confirmed our hypothesis that the activity-dependent transcriptional downregulation of HRs is responsible for the constant light exposure-induced circuitry response changes in L2. The results successfully demonstrated the selective circuit change after synaptic remodeling evoked by long-term activation and provided in vivo evidence of circuitry plasticity upon long-term environmental stimulation.


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