Reduced brown adipose tissue thermogenesis during environmental interactions in transgenic rats with ataxin-3-mediated ablation of hypothalamic orexin neurons

Mohammed, Mazher; Ootsuka, Youichirou; Yanagisawa, Masashi; Blessing, W.W.

doi:10.1152/ajpregu.00260.2014

Cited by 28 publications

(33 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our previous studies have shown that the integrated daily-life ultradian patterns are preserved in transgenic rats (Mohammed et al, 2014). The main difference between the rats and this study on mice is that the ultradian episodic increases in body temperature were almost absent in ORX-KO mice but not in the transgenic rats.…”

Section: Orexin-related Genetically Modified Animals For Ultradian Stcontrasting

confidence: 60%

“…Our preliminary data shows that conditional ablation of orexin neurons attenuates the amplitude of ultradian pattern in metabolism in a time dependent manner (Ootsuka et al, 2014).…”

Section: Orexin-related Genetically Modified Animals For Ultradian Stmentioning

confidence: 73%

“…Thus, we employed continuous wavelet analysis (CWT) to assess the intervals between individual ultradian episodes. CWT provides a localised frequency decomposition and therefore is useful for analysing non-stationary signals (Graps, 1995, Torrence andCompo, 1998) including ultradian variation in biological signals (Poon et al, 1997, Leise, 2013, Mohammed et al, 2014. We used CWT analysis to assess ultradian components in behavioural and physiological signals.…”

Section: Signal Analysis Of Physiological Recordsmentioning

confidence: 99%

“…Our group has already studied the ultradian pattern in transgenic rats with ataxinmediated destruction of the hypothalamic orexin/hypocretin neurons (Mohammed et al, 2014). Orexin has an important role in orchestrating multiple behavioural and physiological functions.…”

Section: Introductionmentioning

confidence: 99%

“…This was done by assessing its intervals and temporal pattern as performed in our rat studies. The issue is particularly important because the wide variety of transgenic mice models provide invaluable opportunities for exploring the brain mechanisms responsible for generating and coordinating the ultradian pattern.Our group has already studied the ultradian pattern in transgenic rats with ataxinmediated destruction of the hypothalamic orexin/hypocretin neurons (Mohammed et al, 2014). Orexin has an important role in orchestrating multiple behavioural and physiological functions.…”

mentioning

confidence: 99%

See 4 more Smart Citations

The integrated ultradian organization of behavior and physiology in mice and the contribution of orexin to the ultradian patterning

Kuwaki

Ootsuka

2016

Neuroscience

Self Cite

View full text Add to dashboard Cite

Our series of rat experiments have shown that locomotor activity, arousal level, body and brown adipose tissue temperatures, heart rate and arterial pressure increase episodically in an integrated manner approximately every 100 min (ultradian manner).Although it has been proposed that the integrated ultradian pattern is a fundamental biological rhythm across species, there are no reports of the integrated ultradian pattern in species other than rats. The aim of the present study was to establish a mice model using simultaneous recording of locomotor activity, eating behaviour, body temperature, heart rate and arousal in order to determine whether their behaviour and physiology are organised in an ultradian manner in normal (wild type) mice. We also incorporated the same recording in prepro-orexin knockout mice to reveal the role of orexin in the brain mechanisms underlying ultradian patterning. The orexin system is one of the key conductors required for coordinating autonomic functions and behaviours, and thus may contribute to ultradian patterning. In wild type mice, locomotor activity, arousal level, body temperature and heart rate increased episodically every 93±18 min (n=8) during 24 hours. Eating was integrated into the ultradian pattern, commencing 23±4 min (n=8) after the onset of an EEG ultradian episode. The integrated ultradian pattern in wild type mice is very similar to that observed in rats. In prepro-orexin knockout mice, the ultradian episodic changes in locomotor activity, EEG arousal indices and body temperature were significantly attenuated, but the ultradian patterning was preserved. Our findings support the view that the ultradian pattern is common across species. The present results also suggest that orexin contributes to driving ultradian episodic changes, however, this neuropeptide is not essential for the generation of the ultradian pattern. Keywordsultradian, orexin knockout mice, body temperature, arousal level, hypothalamus 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 4 IntroductionCircadian variation in behavioural and physiological parameters is well established.What is not so well recognized is the integrated fashion in which each parameter varies within each phase of the day/night cycle as the animal alternates between inactive and active states (Richter, 1927, Honma and Hiroshige, 1978, Shimada and Marsh, 1979, Livnat et al., 1984, Stupfel et al., 1985, Alfoldi et al., 1990, Holstein-Rathlou et al., 1995. It is proposed that, in addition to circadian patterning, ultradian (<24 hour) alternation between active interaction with the external environment and rest is a fundamental part of animal life (Aschoff and Gerkema, 1985, Ootsuka et al., 2011, Blessing et al., 2012, 2013, Blessing and Ootsuka, 2016. The ultradian pattern, also referred to as the basic-rest activity ...

show abstract

Section: Orexin-related Genetically Modified Animals For Ultradian Stcontrasting

confidence: 60%

“…Our preliminary data shows that conditional ablation of orexin neurons attenuates the amplitude of ultradian pattern in metabolism in a time dependent manner (Ootsuka et al, 2014).…”

Section: Orexin-related Genetically Modified Animals For Ultradian Stmentioning

confidence: 73%

Section: Signal Analysis Of Physiological Recordsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

The integrated ultradian organization of behavior and physiology in mice and the contribution of orexin to the ultradian patterning

Kuwaki

Ootsuka

2016

Neuroscience

Self Cite

View full text Add to dashboard Cite

show abstract

Orexin-A promotes Glu uptake by OX1R/PKCα/ERK1/2/GLT-1 pathway in astrocytes and protects co-cultured astrocytes and neurons against apoptosis in anoxia/hypoglycemic injury in vitro

Shu¹,

Zhang²,

Ma³

et al. 2016

Mol Cell Biochem

View full text Add to dashboard Cite

Orexin-A, which is an endogenous neuropeptide, is reported to have a protective role in ischemic stroke. High-concentration glutamic acid (Glu) induced by hypoxia injury in ischemic stroke can be inhibited by glial glutamate transporter GLT-1 which is only expressed in astroglia cells. A previous study reported that Orexin-A may regulate GLT-1 expression. However, the role of orexin-A in the regulation of GLT-1 in ischemic stroke still remains unclear. In this study, we aimed to investigate the effect and the underlying mechanism of orexin-A on Glu uptake in astrocytes in vitro and this effect on protecting the neurons from anoxia/hypoglycemic injury. The expression of GLT-1 significantly increased in the astrocytes with orexin-A treatment under anoxia/hypoglycemic conditions, promoting the uptake of Glu and inhibiting the apoptosis of co-cultured cells of astrocytes and neurons. However, these effects were significantly weakened by treatment with orexin-A receptor 1 (OX1R) antagonist. Orexin-A significantly up-regulated the expressions of PKCα and ERK1/2 under anoxia/hypoglycemic conditions in astrocytes, whereas the OX1R antagonist markedly reversed the effect. Furthermore, PKCα or ERK1/2 inhibitor significantly constrained the GLT-1 expression in astrocytes and facilitated the apoptosis of co-cultured cells, and GLT-1 overexpression could reverse those effects of PKCα or ERK1/2 inhibitor. Taken together, orexin-A promoted the GLT-1 expression via OX1R/PKCα/ERK1/2 pathway in astrocytes and protected co-cultured cells against anoxia/hypoglycemic injury.

show abstract

Cellular Thermometry Considerations for Probing Biochemical Pathways

Rajagopal

Sinha

2021

Cell Biochem Biophys

View full text Add to dashboard Cite

Temperature is a fundamental thermodynamic property that can serve as a probe of biochemical reactions. Extracellular thermometry has previously been used to probe cancer metabolism and thermoregulation, with measured temperature changes of ~1-2 K in tissues, consistent with theoretical predictions. In contrast, previous intracellular thermometry studies remain disputed due to reports of >1 K intracellular temperature rises over 5 min or more that are inconsistent with theory. Thus, the origins of such anomalous temperature rises remain unclear. An improved quantitative understanding of intracellular thermometry is necessary to provide a clearer perspective for future measurements. Here, we develop a generalizable framework for modeling cellular heat diffusion over a range of subcellular-to-tissue length scales. Our model shows that local intracellular temperature changes reach measurable limits (> 0.1 K) only when exogenously stimulated. On the other hand, extracellular temperatures can be measurable (> 0.1 K) in tissues even from endogenous biochemical pathways. Using these insights, we provide a comprehensive approach to choosing an appropriate cellular thermometry technique by analyzing thermogenic reactions of different heat rates and time constants across length scales ranging from sub-cellular to tissues. Our work provides clarity on cellular heat diffusion modeling and on the required thermometry approach for probing thermogenic biochemical pathways.

show abstract

Reduced brown adipose tissue thermogenesis during environmental interactions in transgenic rats with ataxin-3-mediated ablation of hypothalamic orexin neurons

Cited by 28 publications

References 67 publications

The integrated ultradian organization of behavior and physiology in mice and the contribution of orexin to the ultradian patterning

The integrated ultradian organization of behavior and physiology in mice and the contribution of orexin to the ultradian patterning

Orexin-A promotes Glu uptake by OX1R/PKCα/ERK1/2/GLT-1 pathway in astrocytes and protects co-cultured astrocytes and neurons against apoptosis in anoxia/hypoglycemic injury in vitro

Cellular Thermometry Considerations for Probing Biochemical Pathways

Contact Info

Product

Resources

About