Read by QxMD icon Read

Induced hibernation

Ana Stancic, Aleksandra Jankovic, Aleksandra Korac, Dusko Cirovic, Vesna Otasevic, Kenneth B Storey, Bato Korac
In the present study we hypothesized that myocardial adaptive phenotype in mammalian hibernation involves rearrangement of mitochondria bioenergetic pathways providing protective pattern in states of reduced metabolism and low temperature. European ground squirrels (Spermophilus citellus) were exposed to low temperature (4 ± 1 °C) and then divided into two groups: (1) animals that fell into torpor (hibernating group) and (2) animals that stayed active and euthermic for 1, 3, 7, 12, or 21 days (cold-exposed group)...
March 5, 2018: Comparative Biochemistry and Physiology. Part B, Biochemistry & Molecular Biology
Sebastiaan D Hemelrijk, Marcel C Dirkes, Marit H N van Velzen, Rick Bezemer, Thomas M van Gulik, Michal Heger
Hydrogen sulfide (H2 S, 80 ppm) gas in an atmosphere of 17.5% oxygen reportedly induces suspended animation in mice; a state analogous to hibernation that entails hypothermia and hypometabolism. However, exogenous H2 S in combination with 17.5% oxygen is able to induce hypoxia, which in itself is a trigger of hypometabolism/hypothermia. Using non-invasive thermographic imaging, we demonstrated that mice exposed to hypoxia (5% oxygen) reduce their body temperature to ambient temperature. In contrast, animals exposed to 80 ppm H2 S under normoxic conditions did not exhibit a reduction in body temperature compared to normoxic controls...
March 1, 2018: Scientific Reports
Zhenghang Zhao, Raymond K Kudej, Hairuo Wen, Nadezhda Fefelova, Lin Yan, Dorothy E Vatner, Stephen F Vatner, Lai-Hua Xie
Hibernating animals show resistance to hypothermia-induced cardiac arrhythmias. However, it is not clear whether and how mammalian hibernators are resistant to ischemia-induced arrhythmias. The goal of this investigation was to determine the susceptibility of woodchucks ( Marmota monax) to arrhythmias and their mechanisms after coronary artery occlusion at the same room temperature in both winter, the time for hibernation, and summer, when they do not hibernate. By monitoring telemetric electrocardiograms, we found significantly higher arrhythmia scores, calculated as the severity of arrhythmias, with incidence of ventricular tachycardia, ventricular fibrillation, and thus sudden cardiac death (SCD) in woodchucks in summer than they had in winter...
February 28, 2018: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
Bernard W Laughlin, Isaac R Bailey, Sarah A Rice, Zeinab Barati, Lori K Bogren, Kelly L Drew
Targeted temperature management is standard of care for cardiac arrest and is in clinical trials for stroke. N6 -cyclohexyladenosine (CHA), an A1 adenosine receptor agonist, inhibits thermogenesis and induces onset of hibernation in hibernating species. Despite promising thermolytic efficacy of CHA, prior work has failed to achieve and maintain a prescribed target core body temperature (Tb ) between 32°C and 34°C for 24 hours. We instrumented Sprague-Dawley rats (n = 19) with indwelling arterial and venous cannulae and a transmitter for monitoring Tb and ECG, then administered CHA via continuous IV infusion or intraperitoneal (IP) injection...
February 26, 2018: Therapeutic Hypothermia and Temperature Management
Yonggang Niu, Wangjie Cao, Yaofeng Zhao, Haotian Zhai, Yao Zhao, Xiaolong Tang, Qiang Chen
The effect of hibernation on oxidative stress and antioxidant defenses was assessed in the frog Nanorana parkeri which inhabits the southern Tibetan Plateau. We compared the indices of oxidative stress (GSSG/GSH), the degree of oxidative damage (content of carbonyl proteins and lipid peroxide products) and the activities of antioxidant enzymes (SOD, CAT, GPx, GST and GR) in liver, brain, heart and muscle of N. parkeri sampled during summer and winter. Obtained results showed that hibernation induced a significant decrease in the levels of GSH in heart, liver, and muscle, while the ratio of GSSG/GSH markedly increased in all tissues except for muscle...
February 14, 2018: Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology
Shin Nakayama, Noriko Taguchi, Makoto Tanaka
The hydrogen sulfide donor sodium hydrogen sulfide (NaHS) is recognized as a neuroprotective agent, which induces a hibernation-like metabolic state and hypothermia. However, it remains unclear whether it is the sulfide itself or the hypothermia induced by the sulfide that mediates treatment outcomes following cardiac arrest (CA) and cardiopulmonary resuscitation (CPR). We therefore tested whether NaHS improved outcomes following CA/CPR in mice maintained at 35.0°C by active warming during recovery. Adult male mice were subjected to 8 minutes CA/CPR and randomly treated intraperitoneally with either implantation of miniosmotic pump with NaHS (50 μmol/kg/day) for 3 days or vehicle 30 minutes after CPR...
February 12, 2018: Therapeutic Hypothermia and Temperature Management
Denis Abramochkin, Vladislav Kuzmin
The striking seasonal difference in sensitivity of frog cardiac muscle to acetylcholine or stimulation of parasympathetic nervous fibers has been noted almost a century ago, although its electrophysiological basis has never been revealed. The present study compares the effects of the muscarinic agonist carbamylcholine chloride (CCh 10-8-10-5 M) on electrical activity in isolated atrial and ventricular preparations from dormant frogs (Rana temporaria) caught in January (winter-acclimatized, WA) and from active frogs caught in July (summer-acclimatized, SA)...
February 10, 2018: Journal of Comparative Physiology. B, Biochemical, Systemic, and Environmental Physiology
Selma Bouchekioua, Sung-Pyo Hur, Yuki Takeuchi, Young-Don Lee, Akihiro Takemura
Most wrasses are protogynous species that swim to feed, reproduce during the daytime, and bury themselves under the sandy bottom at night. In temperate and subtropical wrasses, low temperature influences emergence from the sandy bottom in the morning, and induces a hibernation-like state in winter. We cloned and characterized the prohormone complementary DNAs (cDNAs) of arginine vasotocin (AVT) and isotocin (IT) in a temperate wrasse (Halichoeres tenuispinis) and examined the effects of day/night and temperature on their expression in the diencephalon, because these neurohypophysial peptides are related to the sex behavior of wrasses...
February 5, 2018: Fish Physiology and Biochemistry
Claudia A F Wascher, Kurt Kotrschal, Walter Arnold
Animals adaptively regulate their metabolic rate and hence energy expenditure over the annual cycle to cope with energetic challenges. We studied energy management in greylag geese. In all geese, profound seasonal changes of heart rate (fH) and body temperature (Tb) showed peaks in summer and troughs during winter, and also daily modulation of fH and Tb. Daily mean fH was on average 22% lower at the winter trough than at the summer peak, whereas daily mean Tb at the winter trough was only about 1 °C below the summer peak...
February 1, 2018: Scientific Reports
Mervyn Singer
An exaggerated, dysregulated host response to insults such as infection (i.e. sepsis), trauma and ischaemia-reperfusion injury can result in multiple organ dysfunction and death. While the focus of research in this area has largely centred on inflammation and immunity, a crucial missing link is the precise identification of mechanisms at the organ level that cause this physiological-biochemical failure. Any hypothesis must reconcile this functional organ failure with minimal signs of cell death, availability of oxygen, and (often) minimal early local inflammatory cell infiltrate...
December 28, 2017: Critical Care: the Official Journal of the Critical Care Forum
Jonathan M Palmer, Kevin P Drees, Jeffrey T Foster, Daniel L Lindner
Bat white-nose syndrome (WNS), caused by the fungal pathogen Pseudogymnoascus destructans, has decimated North American hibernating bats since its emergence in 2006. Here, we utilize comparative genomics to examine the evolutionary history of this pathogen in comparison to six closely related nonpathogenic species. P. destructans displays a large reduction in carbohydrate-utilizing enzymes (CAZymes) and in the predicted secretome (~50%), and an increase in lineage-specific genes. The pathogen has lost a key enzyme, UVE1, in the alternate excision repair (AER) pathway, which is known to contribute to repair of DNA lesions induced by ultraviolet (UV) light...
January 2, 2018: Nature Communications
Andrea Wolf, Elizabeth R Lusczek, Gregory J Beilman
Hemorrhagic shock is the leading cause of preventable death after trauma. Hibernation-based treatment approaches have been of increasing interest for various biomedical applications. Due to apparent similarities in tissue perfusion and metabolic activity between severe blood loss and the hibernating state, hibernation-based approaches have also emerged for the treatment of hemorrhagic shock. Research has shown that hibernators are protected from shock-induced injury and inflammation. Utilizing the adaptive mechanisms that prevent injury in these animals may help alleviate the detrimental effects of hemorrhagic shock in non-hibernating species...
December 27, 2017: Shock
Maximiliano Giraud-Billoud, Alfredo Castro-Vazquez, Alejandra D Campoy-Diaz, Pablo M Giuffrida, Israel A Vega
Pomacea canaliculata may serve as a model organism for comparative studies of oxidative damage and antioxidant defenses in active, hibernating and arousing snails. Oxidative damage (as TBARS), free radical scavenging capacity (as ABTS+ oxidation), uric acid (UA) and glutathione (GSH) concentrations, activities of superoxide dismutase (SOD) and catalase (CAT), and the protein expression levels of heat shock proteins (Hsp70, Hsc70, Hsp90) were studied in digestive gland, kidney and foot. Tissue TBARS of hibernating snails (45days) was higher than active snails...
December 19, 2017: Comparative Biochemistry and Physiology. Part B, Biochemistry & Molecular Biology
Bryan E Luu, Sanoji Wijenayake, Jing Zhang, Shannon N Tessier, Julian F Quintero-Galvis, Juan Diego Gaitán-Espitia, Roberto F Nespolo, Kenneth B Storey
The South American marsupial, monito del monte (Dromiciops gliroides) uses both daily torpor and multi-day hibernation to survive in its southern Chile native environment. The present study leverages multiplex technology to assess the contributions of key stress-inducible cell cycle regulators and heat shock proteins to hibernation in liver, heart, and brain of monito del monte in a comparison of control versus 4day hibernating conditions. The data indicate that MDM2, a stress-responsive ubiquitin ligase, plays a crucial role in marsupial hibernation since all three tissues showed statistically significant increases in MDM2 levels during torpor (1...
December 14, 2017: Comparative Biochemistry and Physiology. Part B, Biochemistry & Molecular Biology
Shinnosuke Kon, Tae Sato, Daisuke Endo, Tomoe Takahashi, Akio Takaku, Yuni Nakauchi, Fubito Toyama, Victor B Meyer-Rochow, Eriko Takayama-Watanabe, Akihiko Watanabe
Sperm storage is supposed to influence sperm quality, although the details remain unclear. In the present study, we found that sperm stored in a sperm storage site, the vas deferens of Cynops pyrrhogaster, spontaneously undergo acrosome reaction following incubation in Steinberg's salt solution (ST). Percentages of acrosome-reacted sperm increased time-dependently to about 60% in 24 hr. The concentration of cyclic adenosine monophosphate (cAMP) was elevated after incubating sperm in ST, while dibutylyl cAMP induced an acrosome reaction...
December 2017: Molecular Reproduction and Development
Michael J Sheriff, Rudy Boonstra, Rupert Palme, C Loren Buck, Brian M Barnes
The Earth's climate is changing at an unprecedented rate and, as ecologists, we are challenged with the difficult task of predicting how individuals and populations will respond to climate-induced changes to local and global ecosystems. Although we are beginning to understand some of the responses to changing seasonality, the physiological mechanisms that may drive these responses remain unknown. Using long-term data comparing two nearby populations (<20 km apart) of free-living arctic ground squirrels in northern Alaska, we have previously shown that the timing of spring snowmelt greatly influences their phenology of hibernation and reproduction in a population and site-specific manner...
2017: Conservation Physiology
Koen D W Hendriks, Eleonora Lupi, Maarten C Hardenberg, Femke Hoogstra-Berends, Leo E Deelman, Robert H Henning
Hibernators show superior resistance to ischemia and hypothermia, also outside the hibernation season. Therefore, hibernation is a promising strategy to decrease cellular damage in a variety of fields, such as organ transplantation. Here, we explored the role of mitochondria herein, by comparing epithelial cell lines from a hibernator (hamster kidney cells, HaK) and a non-hibernator (human embryonic kidney cells, HEK293) during cold preservation at 4 °C and rewarming. Cell survival (Neutral Red), ATP and MDA levels, mitochondrial membrane potential (MMP), mitochondrial morphology (using fluorescent probes) and metabolism (seahorse XF) were assessed...
November 14, 2017: Scientific Reports
Matteo Cerri
While human hibernation would provide many advantages for medical applications and space exploration, the intrinsic risks of the procedure itself, as well as those involved if the procedure were to be misused, need to be assessed. Moreover, the distinctive brain state that is present during a hibernation-like state raises questions regarding the state of consciousness of the subject. Since, in animal studies, the cortical activity of this state differs from that of sleep, coma, or even general anesthesia, and resembles a sort of "slowed wakefulness", it is uncertain whether residual consciousness may still be present...
November 7, 2017: Journal of Integrative Neuroscience
Juergen Pauluhn
This paper reviews the results from past regulatory and mechanistic inhalation studies in rats with the type II pyrethroid Cyfluthrin. Apart from many chemical irritants, Cyfluthrin was shown to be a neuroexcitatory agent without any inherent tissue-destructive or irritant property. Thus, any Cyfluthrin-induced neuroexcitatory afferent sensory stimulus from peripheral nociceptors in the upper respiratory tract is likely to be perceived as a transient stimulus triggering annoyance and/or avoidance by both rats and humans...
January 5, 2018: Toxicology Letters
Clair Hartmann, Benedikt Nussbaum, Enrico Calzia, Peter Radermacher, Martin Wepler
The role of nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2S) as poisonous gases is well-established. However, they are not only endogenously produced but also, at low concentrations, exert beneficial effects, such as anti-inflammation, and cytoprotection. This knowledge initiated the ongoing debate, as to whether these molecules, also referred to as "gaseous mediators" or "gasotransmitters," could serve as novel therapeutic agents. In this context, it is noteworthy, that all gasotransmitters specifically target the mitochondria, and that this interaction may modulate mitochondrial bioenergetics, thereby subsequently affecting metabolic function...
2017: Frontiers in Physiology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"