The crosstalk between PTEN‐induced kinase 1‐mediated mitophagy and the inflammasome in the pathogenesis of alopecia areata

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Abstract

Alopecia areata (AA) is a T-cell-mediated autoimmune disease that causes chronic, relapsing hair loss; however, its precise pathogenesis remains to be elucidated. Recent studies have provided compelling evidence of crosstalk between inflammasomes and mitophagy—a process that contributes to the removal of damaged mitochondria. Our previous studies showed that the NLR family pyrin domain containing 3 (NLRP3) inflammasome is important for eliciting and progressing inflammation in AA. In this study, we detected mitochondrial DNA damage in AA-affected scalp tissues and IFNγ and poly(I:C) treated outer root sheath (ORS) cells. In addition, IFNγ and poly(I:C) treatment increased mitochondrial reactive oxygen species (ROS) levels in ORS cells. Moreover, we showed that mitophagy induction alleviates IFNγ and poly(I:C)-induced NLRP3 inflammasome activation in ORS cells. Lastly, PTEN-induced kinase 1 (PINK1) knockdown increased NLRP3 inflammasome activation, indicating that PINK1-mediated mitophagy plays a critical role in NLRP3 inflammasome activation in ORS cells. This study supports previous studies showing that oxidative stress disrupts immune privilege status and promotes autoimmunity in AA. The results emphasize the significance of crosstalk between mitophagy and inflammasomes in the pathogenesis of AA. Finally, mitophagy factors regulating mitochondrial dysfunction and inhibiting inflammasome activation could be novel therapeutic targets for AA.

Effect of intramuscular fat content on the sensory characteristics and dynamic flavor attributes of Japanese black cattle beef

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Abstract

The intramuscular fat (IMF) in beef affects its flavor intensity and attributes, which have a significant impact on palatability. We conducted a sensory evaluation by descriptive analysis, Temporal Check-All-That-Apply, and a chemical analysis of 40 ribeye steaks from Japanese Black cattle to determine the relationship among IMF% and sensory characteristics including dynamic flavor attributes. The increased IMF% of Japanese Black cattle beef had intensified sweet and grilled/roasted flavors and reduced off-flavor, whereas excessive IMF% resulted in a decrease in water-soluble precursors of volatile and taste compounds including free amino acid and reducing sugars and weakened the flavor intensities. Beef with IMF% of approximately 40% exhibited strong and long-lasting sweet and grilled/roasted flavors represented by butter- and roasted nut-like, respectively, and a low perception of off-flavors represented by gamey, bloody, and grassy. These flavor attributes may be responsible for its high flavor intensity and overall evaluation score, whereas an IMF% of >55% lowered these scores. The excessive IMF% of beef may induce the less palatable sensory characteristics.

Variation in the supercooling points of laboratory-reared Canadian Dermacentor variabilis (Acari: Ixodidae)

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Canadian Journal of Zoology, Volume 101, Issue 10, Page 930-935, October 2023.
The geographical range of the American dog tick, Dermacentor variabilis (Say, 1821) in Canada is expanding northwards into areas where ticks experience colder temperatures during winter. Understanding the ability of D. variabilis to cope with freezing temperatures is important for determining what limits the distributional range of this species. In this study, the supercooling point (SCP = the sub-zero temperature at which freezing occurs) was measured for 318 laboratory-reared D. variabilis individuals (109 nymphs and 209 adults). These ticks were reared from questing adult ticks collected from an area adjacent to Blackstrap Provincial Park in Saskatchewan, Canada. The results showed that there was no relationship between the SCP and body weight of adult ticks, and no difference in the SCP of female and male ticks. However, the mean SCP of nymphs (−23.6 °C) was significantly lower than that of adults (−21.6 °C). The biological significance of this finding needs to be explored further given that D. variabilis larvae and adults are the primary overwintering stages at northern latitudes.

Short-term effects of camera trap installation on incubation constancy in cranes

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Canadian Journal of Zoology, Volume 101, Issue 10, Page 896-903, October 2023.
Research regarding how birds respond to the installation of cameras at nest sites is limited. We installed cameras at nests of Sandhill Cranes Antigone canadensis (Linnaeus, 1758) and federally endangered Whooping Cranes Grus americana Linnaeus, 1758 in Juneau County, WI, as part of an ongoing study monitoring the reproductive success of Whooping Cranes in WI. The eastern population of Sandhill Cranes has grown, while Whooping Crane population growth has been slow, prompting the need to monitor the reproductive success of cranes on the refuge. We recorded the flight initiation distance during camera installation, the return time after camera installation, as well as measured the distance at which cameras were placed from each nest. We included temperature at camera deployment, age of nest, mode of access, ordinal date, and year in statistical regression models. We found an apparent difference in the observed flight initiation distances between the two species. Sandhill Cranes allowed researchers to approach their nests closer than Whooping Cranes prior to flushing. The post-disturbance return time was influenced by how far away the cameras were placed from the nest and the ambient temperature during camera deploy. Our study may help inform decisions regarding species response to methods and distance when deploying cameras, especially for endangered or disturbance-sensitive species.

Prevention of neurotoxicity and cognitive impairment induced by zinc nanoparticles by oral administration of saffron extract

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Abstract

The accumulation of relatively higher dose of zinc oxide nanoparticles in brain was reported to produce neurotoxicity. Indeed, nanoparticles have a high ability to penetrate biological membranes and be uptaken by cells, which may cause cell disorders and physiological dysfunctions. The aim of the current study was to evaluate, whether oral administration of saffron extract, in rats, can protect from neurotoxicity and behavioural disturbances induced by chronic administration of ZnO-NPs. Daily oral administration of ZnO-NPs was performed for 21 consecutive days to induce oxidative stress-like situation. Then after the saffron extract was concomitantly administrated in several rat groups to overcome the nanotoxicological effect induced by ZnO-NPs. In the frontal cortex, the hippocampus and the cerebellum, ZnO-NPs induced a H2O2-oxydative stress-like effect reflected in reduced enzymatic activities of catalase, superoxide dismutase and glutathione S-transferase, and decreased acetylcholinesterase activity. In addition, increased levels of proinflammatory interleukins IL-6 and IL-1-⍺ occurred in the hippocampus, reveal the existence of brain inflammation. The concomitant administration of saffron extract to animals exposed to ZnO-NPs prevented the enhanced anxiety-related to the behaviour in the elevated plus-maze test, the open field test and preserved spatial learning abilities in the Morris water maze. Moreover, animals exposed to ZnO-NPs and saffron showed abnormal activity of several antioxidant enzymes as well as acetylcholinesterase activity, an effect that may underly the preserved anxiety-like behaviour and spatial learning abilities observed in these animals. Saffron extract has a potential beneficial therapeutic effect: antioxidant, anti-inflammatory and neuroprotective agent.

Loss of body weight and lean mass in long‐stay, hospitalized canine patients

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Abstract

A high prevalence of malnutrition occurs in human hospitals and has been associated with detrimental consequences. By comparison, much less is known in hospitalized veterinary patients. The aims of this study were to evaluate the prevalence of malnutrition and body composition changes in long-stay hospitalised patients using an isotopic dilution technique. An additional objective was to compare the changes in composition with commonly used methods measuring body fat and lean mass. The dogs consumed on average 77.5% of their estimated resting energy requirements during their stay. The majority (78.3%) of dogs lost body weight, of which a greater proportion was lean mass (61.8%) than fat mass (FM) (38.2%). There was a moderate correlation between body condition score and percentage FM measured at admission (Kendall's τ = 0.51; p = 0.002), and at discharge (Kendall's τ = 0.55; p = 0.001). However, there was no correlation between muscle condition score and fat-free mass at either admission or discharge (p > 0.1). Duration of stay was positively associated with loss of body weight (p < 0.001), but was not associated with changes in either lean or FM expressed as a percentage of body weight or in absolute terms (p > 0.1), which was presumed to be explained by small sample size and variation. Food intake was not found to a significant factor for lean or FM loss (p > 0.1). These findings indicate that weight loss is common in hospitalized canine patients, which is not explained by simple under-eating. Other factors such as inflammation and inactivity should be evaluated in future studies to determine their role in influencing muscle and FM changes in hospitalized canine patients.

Changes in piglet and litter characteristics across parities in two highly prolific sow hybrids in an outdoor organic herd

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Abstract

High piglet mortality constitutes a welfare challenge in organic pig production. Litter characteristics were investigated from parities 1–5 of two hyper-prolific hybrids with different selection traits in an organic commercial herd (DanBred vs. Topigs Norsvin [TN70]). TN70 sows had more functional teats than DanBred sows, and their offspring had higher birth weights. Several interactions between hybrid and parity were found. The total born increased with higher parity and was more pronounced for DanBred sows. Litter weight at weaning was higher in parities 1–4 for TN70 compared with DanBred, and within DanBred parities 4 and 5 had higher litter weight at weaning than parity 1. The survival rate was higher for TN70 in parities 1 and 2 compared with DanBred, and for both hybrids, the survival rate was higher in parities 1 and 2 compared with parities 4 and 5. The number of weaned piglets was stable across parities 1–4 but lower in parity 5 for both hybrids. Thus, despite a lower number of total born piglets in TN70, TN70 sows weaned the same number of piglets as DanBred, with a lower mortality rate and a heavier litter at weaning.

Ethanolamine plasmalogens derived from whale brain stimulate both follicle‐stimulating hormone and luteinizing hormone secretion by bovine gonadotrophs

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Abstract

Ethanolamine plasmalogens (EPls) are the only known ligands of a novel receptor, G protein-coupled receptor 61, and bovine brain EPls stimulate follicle-stimulating hormone (FSH) but not luteinizing hormone (LH), secreted by bovine gonadotrophs. We hypothesized that the brain EPls of whales (Balaenoptera edeni), another Cetartiodactyla with at least twice the lifespan of bovines, could stimulate FSH secretion by gonadotrophs. To test this hypothesis, bovine gonadotrophs (from approximately 2-year-old Japanese Black heifers) were cultured for 3.5 days and treated with increasing concentrations of brain EP1s from whales (approximately 22 years old). FSH and LH secretion was stimulated by all tested concentrations of whale EPls (p < 0.05). To clarify the important differences between bovine and whale EPls, we utilized two-dimensional liquid chromatography–mass spectrometry, which revealed 35 peaks. Among them, we observed significant differences between 12 EPl molecular species. Additionally, we identified differentially expressed genes for enzymes involved in EPl synthesis or degradation in the hypothalamus of young heifers and old cows (approximately 10 years old) as compared to whales (approximately 28 years old) via deep sequencing of the transcriptome. We conclude that whale brains contain unique EPls that stimulate both FSH and LH secretion by bovine gonadotrophs.

The capacity of ante‐mortem inspection of pigs at the abattoir to predict post‐mortem findings and associated financial implications: A study at batch level

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Abstract

This study aimed to investigate the associations between severe ear, tail, and skin lesions, hernias, bursitis, and rectal prolapses and meat inspection finding in slaughter pigs, including carcass weight and financial implications associated with carcass condemnations at batch level. Data were collected from 13,296 pigs from 116 batches from a single abattoir. Spearman's correlation coefficients were calculated to analyze the degree of association between the prevalence of welfare issues and condemnation findings. The association between batch-level results of carcass weight, batch size, and the prevalence of welfare issues was analyzed using generalized linear mixed models. The prevalence of tail lesions was significantly associated with both entire (r = 0.224; p = 0.0432) and partial (r = 0.276; p = 0.0120) carcass condemnation. Batches with pigs affected by more than one welfare issue were 9.9 kg lighter than those without welfare issues (p < 0.05), which was equivalent to a potential loss of €11.28 per pig. Our findings indicate that ante-mortem inspection could be useful to predict post-mortem findings at batch level and that welfare issues in pigs represent a financial loss to producers, as they are paid on a per kg basis and have tight margins.

Effects of bat white-nose syndrome on hibernation and swarming aggregations of bats in Ontario

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Canadian Journal of Zoology, Volume 101, Issue 10, Page 886-895, October 2023.
Emerging infectious diseases can have substantial impacts on wildlife health, but also provide an opportunity to understand how populations respond to novel selective pressures. White-nose syndrome (WNS) has decimated some populations of bats in eastern North America, but impacts vary among species. We counted bats in 11 hibernacula in Ontario, Canada, before and after WNS arrived, and compared the relative abundance of 5 bat species captured pre-WNS (1966–1968 and 2007–2009) and post-WNS (2017–2019) during swarming at one of these hibernacula. Counts of hibernating bats declined by 87%–100% after WNS arrived. However, we observed a recent, gradual increase in bat counts in the two largest, monitored hibernacula. During swarming, little brown bat (Myotis lucifugus (Le Conte, 1831)) was the most frequently captured bat in all sampling periods. Capture frequency of northern long-eared bat (Myotis septentrionalis (Trouessart, 1897)) declined precipitously after WNS arrived, while eastern small-footed bat (Myotis leibii (Audubon and Bachman, 1842) represented a higher proportion of bat captures in 2017–2019 compared to other sampling periods. Our data suggest potential adaptation of some bat populations to WNS, but also highlight the importance of protecting bats and their habitat during the active season to facilitate population recovery.