Bat Tissues Research Articles

Detecting SARS-CoV-2 in bats of New Mexico using immunohistochemistry on formalin- fixed, paraffn-embedded tissues

Objectives: The emergence of severe acute respiratory syndrome coronavirus (SARS-CoV-2) and its zoonotic origin have raised critical questions regarding the potential role of local bat populations as reservoirs or intermediates for the transmission of this or related coronaviruses to humans. The goal of this project is to investigate the presence and diversity of coronaviruses in bat species native to the Southwest USA. Broadly, this study has two primary aims: (1) to detect antigens of coronaviruses in tissues of local bat populations via histological methods and (2) to perform a molecular screen of coronaviruses in these bats. Methods: Individuals from five bat species were evaluated: Artibeus jamaicensis, Myotis velifer, Antrozous pallidus, Tadarida brasiliensis, and Eptesicus fuscus. All species were local, wild-caught bats, with the exception of Artibeus jamaicensis, which is from a colony established at New Mexico State University (NMSU). Tissue was sourced from bats collected by TJO at NMSU. Bat tissue was fixed with formalin and samples subsequently taken of lung, kidney, nasal epithelium, and uterus. Tissue was further processed and embedded in paraffn wax. The embedded tissue was sectioned via a rotary microtome at 4 μm thickness and mounted onto slides. Slides were stained with general coronavirus anti-nucleocapsid primary antibody and a hematoxylin counterstain to visualize cellular structures. Slides were cover-slipped with DPX mounting medium and observed via light microscopy. Results: The immunohistochemistry protocol was performed on tissue from each of the five bat species investigated and on human placenta samples known to be positive for SARS-CoV-2. The latter was used as positive controls. Putative positive staining was seen in both human placenta and bat tissues. Interestingly, coronavirus was detected in Artibeus jamaicensis samples, an unexpected finding given its status as a laboratory colony. Verification of this putative finding is ongoing. Further work on our samples will determine the genetic identity of the coronaviruses detected and contribute to developing a molecular screen for more effcient detection of coronavirus antigens in local bat tissue. This work will serve as a springboard for further understanding coronavirus ecology and evolution in bats of the US southwest, and it can be used to further inform both local surveillance efforts and public policy surrounding the interaction between humans and animals in the natural environment and in controlled settings. Conclusions: Putative detection of coronavirus antigens was found in tissues from bat samples from the Southwestern USA. Implications for this work include broadening our understanding of the diversity and abundance of coronaviruses in the US. Burrell College; US National Science Foundation. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Establishment of immortalized Egyptian Rousettus bat cell lines.

The Egyptian Rousettus bat (Rousettus aegyptiacus) is a common fruit bat species that is distributed mainly in Africa and the Middle East. Bats serve as reservoir hosts for numerous pathogens. Human activities, such as hunting bats for food, managing vermin, and causing habitat loss, elevate the likelihood of transmission of bat pathogens to humans and other animals. Consequently, bat cell lines play a crucial role as research materials for investigating viral pathogens. However, the inherent limitation of finite cell division in primary cells necessitates the use of immortalized cells derived from various bat tissues. Herein, we successfully established six fibroblast cell lines derived from an infant bat heart and lungs and an elderly bat heart. Three of the six cell lines, called K4DT cells, were transduced by a combination of cell cycle regulators, mutant cyclin-dependent kinase 4, cyclin D1, and human telomerase reverse transcriptase. The other three cell lines, named SV40 cells, were transfected with simian virus 40 large T antigen. Transgene protein expression was detected in the transduced cells. All three K4DT cell lines and one lung-derived SV40 cell line were virtually immortalized and nearly maintained the normal diploid karyotypes. However, the two other heart-derived SV40 cell lines had aberrant karyotypes and the young bat-derived cell line stopped proliferating at approximately 40 population doublings. These bat cell lines are valuable for studying pathogen genomics and biology.

Iron and aluminum ore mining pollution induce oxidative and tissue damage on fruit-eating bats from the Atlantic Forest

Mining, a vital industry for economic growth, poses significant environmental pollution challenges. Failures in tailings dam containment have caused environmental contamination and raised concerns about preserving the globally significant biodiversity in the Atlantic Forest, which is under severe threat. Fruit-eating bats are key for forest regeneration as essential seed dispersers and pollinators. This study focuses on two keystone species, Artibeus lituratus and Sturnira lilium, exploring the effects of iron ore mining area (FEOA) and aluminum ore mining area (ALOA) on these bats, respectively, and comparing to individuals from a preserved Atlantic Forest fragment (FFA). Bats from FEOA showed higher Aluminum (Al), Calcium (Ca), Iron (Fe) and Barium (Ba) liver accumulation, as well as Ca and Fe muscle accumulation. These animals also showed higher liver and kidney oxidative damage associated with liver fibrosis and kidney inflammation. Brain and muscle also showed oxidative stress. Bats from ALOA showed higher Ca and Ba liver accumulation and Ca, Zinc (Zn), and Ba muscle accumulation, along with higher brain oxidative stress, liver fibrosis, and kidney inflammation. Our findings indicate that iron and aluminum ore mining activities cause adverse effects on bat tissues, posing a potential threat to biodiversity maintenance in the Atlantic Forest.

Virulent Brucella nosferati infecting Desmodus rotundus has emerging potential due to the broad foraging range of its bat host for humans and wild and domestic animals.

Desmodus rotundus, vampire bats, transmit dangerous infections, and brucellosis is a hazardous zoonotic disease, two adversities that coexist in the subtropical and tropical areas of the American continent. Here, we report a 47.89% Brucella infection prevalence in a colony of vampire bats inhabiting the tropical rainforest of Costa Rica. The bacterium induced placentitis and fetal death in bats. Wide-range phenotypic and genotypic characterization placed the Brucella organisms as a new pathogenic species named Brucella nosferati sp. nov., isolated from bat tissues, including the salivary glands, suggesting feeding behavior might favor transmission to their prey. Overall analyses placed B. nosferati as the etiological agent of a reported canine brucellosis case, demonstrating its potential for infecting other hosts. To assess the putative prey hosts, we analyzed the intestinal contents of 14 infected and 23 non-infected bats by proteomics. A total of 54,508 peptides sorted into 7,203 unique peptides corresponding to 1,521 proteins were identified. Twenty-three wildlife and domestic taxa, including humans, were foraged by B. nosferati-infected D. rotundus, suggesting contact of this bacterium with a broad range of hosts. Our approach is appropriate for detecting, in a single study, the prey preferences of vampire bats in a diverse area, demonstrating its suitability for control strategies where vampire bats thrive. IMPORTANCE The discovery that a high proportion of vampire bats in a tropical area is infected with pathogenic Brucella nosferati and that bats forage on humans and many wild and domestic animals is relevant from the perspective of emerging disease prevention. Indeed, bats harboring B. nosferati in their salivary glands may transmit this pathogenic bacterium to other hosts. This potential is not trivial since, besides the demonstrated pathogenicity, this bacterium possesses all the required virulent arsenal of dangerous Brucella organisms, including those that are zoonotic for humans. Our work has settled the basis for future surveillance actions in brucellosis control programs where these infected bats thrive. Moreover, our strategy to identify the foraging range of bats may be adapted for exploring the feeding habits of diverse animals, including arthropod vectors of infectious diseases, and therefore of interest to a broader audience besides experts on Brucella and bats.

Comparing little brown and big brown bat isotopic niches over the past century in an agriculturally dominated landscape

Abstract Agricultural intensification has caused population declines and reduced species diversity in both arthropods and their predators. Despite conservation and habitat management implications, the effects of land-use change on the trophic relationships between nocturnal arthropod predators and their prey have seldom been described. To assess how arthropodivorous bats may have shifted their diets in response to land-use changes, we compared bulk δ 13C and δ 15N values from little brown and big brown bat museum specimens and carcasses collected in the Upper Midwestern region of the United States from 1898 to 2019. As an exploratory analysis, we also investigated relationships between isotopic values and climate or landcover variables to quantify potential correlations with changes in arthropodivorous bat foraging patterns over time. Overall, we found that isotopic niche overlap of little brown and big brown bats increased from 24% to 45% between historical and contemporary time periods. Our results indicate that the isotopic niches of little brown bats have been largely conserved, whereas the isotopic niches of big brown bats are more flexible and became more similar to little brown bats over time. Further analyses showed that stable isotope values from arthropodivorous bat tissues were also correlated with certain landcover variables such as the prevalence of wetland, forest, and grassland habitats, but not with the prevalence of agricultural land on a local scale. These findings suggest that the foraging patterns of some aerial arthropodivores have shifted in response to the loss of habitat diversity and corresponding changes in prey resources.

The Use of Intrinsic Markers for Studying the Migratory Movements of Bats.

Simple SummaryMigratory bats species are among the most heavily impacted by the erection of wind energy facilities, with many individuals killed at wind turbines each year. Bat carcasses may be collected and used for a variety of biological studies. In this paper, we review the use of intrinsic markers—chemical signatures in bat tissues that can provide information about that animal’s life history—to study bat movements across the landscape. In doing so, we aim to provide our audience with a better understanding of the currently available literature and, more importantly, the areas of this field that need expansion. We emphasize the applications of intrinsic markers that have not been used extensively to study migratory bat species (i.e., trace elements, contaminants, strontium isotopes), and provide a workflow for researchers interested in conducting studies of this type.Mortality of migratory bat species at wind energy facilities is a well-documented phenomenon, and mitigation and management are partially constrained by the current limited knowledge of bat migratory movements. Analyses of biochemical signatures in bat tissues (“intrinsic markers”) can provide information about the migratory origins of individual bats. Many tissue samples for intrinsic marker analysis may be collected from living and dead bats, including carcasses collected at wind energy facilities. In this paper, we review the full suite of available intrinsic marker analysis techniques that may be used to study bat migration, with the goal of summarizing the current literature and highlighting knowledge gaps and opportunities. We discuss applications of the stable isotopes of hydrogen, oxygen, nitrogen, carbon, sulfur; radiogenic strontium isotopes; trace elements and contaminants; and the combination of these markers with each other and with other extrinsic markers. We further discuss the tissue types that may be analyzed for each and provide a synthesis of the generalized workflow required to link bats to origins using intrinsic markers. While stable hydrogen isotope techniques have clearly been the leading approach to infer migratory bat movement patterns across the landscape, here we emphasize a variety of lesser used intrinsic markers (i.e., strontium, trace elements, contaminants) that may address new study areas or answer novel research questions.

Non-invasive sampling of bats reflects their potential as ecological indicators of elemental exposure in a diamond mining area, northern Limpopo Province, South Africa

Bats have been proposed as reliable bioindicators for monitoring bioaccumulation of elements and chemicals in natural and transformed ecosystems. Non-invasive methods are becoming more popular as research moves away from destructive methodologies. We present the first concentrations of 23 elements in Mops condylurus and Tadarida aegyptiaca (Molossidae) fur and blood from an opencast diamond mine and reference area using inductively coupled plasma mass spectrometry (ICP-MS). Concentrations of B, K, Rb and Cd in the bats’ fur were significantly higher in the mining footprint compared to the reference area (P < 0.05). Other elements such as Zn and Hg were significantly higher in the blood of bats from the mining footprint than the reference area (P < 0.05), whereas Mn was significantly higher in the blood of bats from the reference area than from the mining footprint (P < 0.05). Sixteen of the 22 elements above the limit of detection, with the exception of Ba, were significantly higher in the fur samples than in the blood due to elements being incorporated over time into the fur as it grows, whereas blood reveals short-term exposure to elements. Concentrations of most of the elements were reasonably low except Al, Fe and Zn. In general, the element concentrations particularly in the fur samples were comparable with other international studies reporting elemental fur concentrations from anthropogenically impacted and natural areas. Fur and blood have the potential to be viable indicators of environmental toxicity, but research is required on toxic thresholds and physiological and ecological unknowns around element concentrations in bat tissues and organs.

Combination of TRP channel dietary agonists induces energy expending and glucose utilizing phenotype in HFD-fed mice.

Bioactive dietary constituents activating Transient receptor potential (TRP) channels have emerged as promising candidates for the prevention of metabolic disorders. The present study is an attempt to evaluate anti-obesity potential of a dietary TRP-based tri-agonist, combination of sub-effective doses of capsaicin (TRPV1 agonist), menthol (TRPM8 agonist), and cinnamaldehyde (TRPA1 agonist) in high-fat diet (HFD)-fed mice. Male C57BL/6 J mice divided into three groups (n = 8), were fed on normal pellet diet (NPD), or high-fat diet (HFD) (60% energy by fat) and HFD + CB (combination of capsaicin 0.4 mg/Kg, menthol 20 mg/Kg, and cinnamaldehyde 2 mg/Kg; p.o) for 12 weeks. Effects on HFD-induced weight gain, biochemical, histological and genomic changes in the WAT, BAT, liver and hypothalamus tissues were studied. Administration of tri-agonist prevented HFD-induced increase in weight gain, improved altered morphometric parameters, glucose homeostasis, and adipose tissue hypertrophy. Tri-agonist supplementation was found to induce browning of white adipose tissue and promote brown adipose tissue activation. Enhanced glucose utilization and prevention of lipid accumulation and insulin resistance in the liver was observed in mice supplemented with a tri-agonist. The present work provides evidence that the new approach based on combination of sub-effective doses of TRP channel agonists (TRI-AGONIST) can be employed to develop concept-based functional food for therapeutic and preventive strategies against HFD-associated pathological complications.

Trans-2-hexenal downregulates several pathogenicity genes of Pseudogymnoascus destructans, the causative agent of white-nose syndrome in bats.

White-nose syndrome is an emergent wildlife disease that has killed millions of North American bats. It is caused by Pseudogymnoascus destructans, a cold-loving, invasive fungal pathogen that grows on bat tissues and disrupts normal hibernation patterns. Previous work identified trans-2-hexenal as a fungistatic volatile compound that potentially could be used as a fumigant against P. destructans in bat hibernacula. To determine the physiological responses of the fungus to trans-2-hexenal exposure, we characterized the P. destructans transcriptome in the presence and absence of trans-2-hexenal. Specifically, we analyzed the effects of sublethal concentrations (5 μmol/L, 10 μmol/L, and 20 μmol/L) of gas-phase trans-2-hexenal of the fungus grown in liquid culture. Among the three treatments, a total of 407 unique differentially expressed genes (DEGs) were identified, of which 74 were commonly affected across all three treatments, with 44 upregulated and 30 downregulated. Downregulated DEGs included several probable virulence genes including those coding for a high-affinity iron permease, a superoxide dismutase, and two protein-degrading enzymes. There was an accompanying upregulation of an ion homeostasis gene, as well as several genes involved in transcription, translation, and other essential cellular processes. These data provide insights into the mechanisms of action of trans-2-hexenal as an anti-fungal fumigant that is active at cold temperatures and will guide future studies on the molecular mechanisms by which six carbon volatiles inhibit growth of P. destructans and other pathogenic fungi.

The Serological Cross-Detection of Bat-Borne Hantaviruses: A Valid Strategy or Taking Chances?

Bats are hosts of a range of viruses, and their great diversity and unique characteristics that distinguish them from all other mammals have been related to the maintenance, evolution, and dissemination of these pathogens. Recently, very divergent hantaviruses have been discovered in distinct species of bats worldwide, but their association with human disease remains unclear. Considering the low success rates of detecting hantavirus RNA in bat tissues and that to date no hantaviruses have been isolated from bat samples, immunodiagnostic tools could be very helpful to understand pathogenesis, epidemiology, and geographic range of bat-borne hantaviruses. In this sense, we aimed to identify in silico immunogenic B-cell epitopes present on bat-borne hantaviruses nucleoprotein (NP) and verify if they are conserved among them and other selected members of Mammantavirinae, using a combination of (the three most used) different prediction algorithms, ELLIPRO, Discotope 2.0, and PEPITO server. To support our data, we in silico modeled 3D structures of NPs from representative members of bat-borne hantaviruses, using comparative and ab initio methods due to the absence of crystallographic structures of studied proteins or similar models in the Protein Data Bank. Our analysis demonstrated the antigenic complexity of the bat-borne hantaviruses group, showing a low sequence conservation of epitopes among members of its own group and a minor conservation degree in comparison to Orthohantavirus, with a recognized importance to public health. Our data suggest that the use of recombinant rodent-borne hantavirus NPs to cross-detect antibodies against bat- or shrew-borne viruses could underestimate the real impact of this virus in nature.

No evidence of SARS-CoV-2 infection in Rousettus aegyptiacus bat in Egypt

ABSTRACT Bats are considered ideal reservoirs for zoonotic viruses with emerging capabilities over the past two decades and spotted evidence points out that they may play a role as a reservoir host for SARS-CoV-2. To investigate the possible role of bats as part of SARS-CoV-2 anthropozoonotic spill-over infections in Egypt, a total of 800 samples obtained from 200 Egyptian fruit bats (Rousettus aegyptiacus) were tested for SARS-CoV-2 using quantitative RT-PCR assay (RT-qPCR). RT-qPCR analysis of RNA extracted from bat tissues showed no positive results for SARS-CoV-2 nucleic acid. These findings suggest that during the study period, the Rousettus aegyptiacus bat was not a reservoir or amplifying host for SARS-CoV-2 infection in Egypt. The lack of SARS-CoV-2 nucleic acid in Egyptian fruit bats is thought to make a significant contribution to SARS-CoV-2 epidemiology.

Interferon Regulatory Factors IRF1 and IRF7 Directly Regulate Gene Expression in Bats in Response to Viral Infection

Bat cells and tissue have elevated basal expression levels of antiviral genes commonly associated with interferon alpha (IFNα) signaling. Here, we show Interferon Regulatory Factor 1 (IRF1), 3, and 7 levels are elevated in most bat tissues and that, basally, IRFs contribute to the expression of type I IFN ligands and high expression of interferon regulated genes (IRGs). CRISPR knockout (KO) of IRF 1/3/7 in cells reveals distinct subsets of genes affected by each IRF in an IFN-ligand signaling-dependent and largely independent manner. As the master regulators of innate immunity, the IRFs control the kinetics and maintenance of the IRG response and play essential roles in response to influenza A virus (IAV), herpes simplex virus 1 (HSV-1), Melaka virus/Pteropine orthoreovirus 3 Melaka (PRV3M), and Middle East respiratory syndrome-related coronavirus (MERS-CoV) infection. With its differential expression in bats compared to that in humans, this highlights a critical role for basal IRF expression in viral responses and potentially immune cell development in bats with relevance for IRF function in human biology.

Test for Borrelia spp. in bats in an urban area in the South of Brazil.

We investigated the occurrence of relapsing fever (RF) causing Borrelia genus spirochetes in synanthropic bats from the municipality of Maringá, Paraná, South of Brazil. Tissue samples from the wings of bats were collected monthly from April 2013 to February 2014 and extracted DNA was used to evaluate the presence of RF causing Borrelia spp. All bat tissues tested negative for RF causing Borrelia spp. Borrelia spp. do not occur in chiropterans from Maringá.

Activation of estrogen receptor alpha induces beiging of adipocytes

ObjectivesBrown adipose tissue (BAT) and BAT-like adipose tissues, referred to as ‘beige’ adipose tissues uncouple respiration from ATP synthesis via uncoupling protein one (UCP-1). There is a sexual dimorphism with respect to beige and BAT tissues; pre-menopausal women have more BAT and are more sensitive to BAT activation than men or postmenopausal women. We hypothesized selective activation of adipose tissue estrogen receptor alpha (ERα) induces beiging of WAT through induction of lipolysis mediated by adipose tissue triglyceride lipase (ATGL). Methods3T3-L1 and primary adipocytes were treated with the selective ERα agonist pyrazole triol (PPT), and selection deletion of ERα (using siRNA) was used to determine if selective ERα activation, or inhibition, influences the adipose tissue expression of genes associated with beiging. In a second series of experiments, ERα was selectively added back to adipose tissue of mice lacking total body ERα (ERKO) to determine if add back of ERα changed the morphology of adipose tissue to resemble beige tissues. Additionally, WT and ERKO mice were exposed to cold and FDG labeled glucose uptake was measured to determine the ability of cold to induce UCP-1 in ERKO mice. To begin to mechanistically probe how activation of ERα facilitates beiging, we tested the influence of PPT to activate the lipolytic pathway through ATGL. Finally, since ERα exerts its effects both at the genomic and non-genomic level depending on its cellular location, we determined in vivo if beiging occurs in mice expressing ERα only at the plasma membrane (MOER mice) or only at nucleus (NOER mice). ResultsSelective ERα activation by PPT increased markers of beiging in vitro in 3T3-L1 and primary adipocytes, whereas, knockdown of ERα with siRNA reduced the ability of PPT to induce beiging in vitro. ERα add back to the adipose tissue of ERKO mice resulted in multilocular adipose tissue resembling a beige phenotype. Following cold exposure, FDG labeled glucose in BAT tissues of ERKO mice was reduced when compared to weight-matched controls. Glycerol release and ATGL expression were increased after PPT treatment, while pre-treatment with the ATGL inhibitor prevented PPT's ability to increase UCP-1 expression. Finally, MOER mice were more sensitive to beiging of adipose tissues when compared to NOER mice. ConclusionOur results demonstrate for the first time that selective-activation of ERα in adipocytes increases markers of beiging and this is likely through induction of AMPK and ATGL-mediated lipolysis providing FFAs as a fuel to activate UCP-1.

Phenotype profiling of white-nose syndrome pathogen Pseudogymnoascus destructans and closely-related Pseudogymnoascus pannorum reveals metabolic differences underlying fungal lifestyles.

Background:Pseudogymnoascusdestructans, a psychrophile, causes bat white-nose syndrome (WNS). Pseudogymnoascus pannorum, a closely related fungus, causes human and canine diseases rarely. Both pathogens were reported from the same mines and caves in the United States, but only P. destructans caused WNS. Earlier genome comparisons revealed that P. pannorum contained more deduced proteins with ascribed enzymatic functions than P. destructans. Methods: We performed metabolic profiling with Biolog PM microarray plates to confirm in silico gene predictions. Results:P. pannorum utilized 78 of 190 carbon sources (41%), and 41 of 91 nitrogen compounds (43%) tested. P. destructans used 23 carbon compounds (12%) and 23 nitrogen compounds (24%). P. destructans exhibited more robust growth on the phosphorous compounds and nutrient supplements (83% and 15%, respectively) compared to P. pannorum (27% and 1%, respectively.). P. pannorum exhibited higher tolerance to osmolytes, pH extremes, and a variety of chemical compounds than P. destructans. Conclusions: An abundance of carbohydrate degradation pathways combined with robust stress tolerance provided clues for the soil distribution of P. pannorum. The limited metabolic profile of P. destructanswas compatible with in silico predictions of far fewer proteins and enzymes. P. destructans ability to catabolize diverse phosphorous and nutrient supplements might be critical in the colonization and invasion of bat tissues. The present study of 1,047 different metabolic activities provides a framework for future gene-function investigations of the unique biology of the psychrophilic fungi.

Phenotype profiling of white-nose syndrome pathogen Pseudogymnoascus destructans and closely-related Pseudogymnoascus pannorum reveals metabolic differences underlying fungal lifestyles

Background: Pseudogymnoascus destructans, a psychrophile, causes bat white-nose syndrome (WNS). Pseudogymnoascus pannorum, a closely related fungus, causes human and canine diseases rarely. Both pathogens were reported from the same mines and caves in the United States, but only P. destructans caused WNS. Earlier genome comparisons revealed that P. pannorum contained more deduced proteins with ascribed enzymatic functions than P. destructans. Methods: We performed metabolic profiling with Biolog PM microarray plates to confirm in silico gene predictions. Results: P. pannorum utilized 78 of 190 carbon sources (41%), and 41 of 91 nitrogen compounds (43%) tested. P. destructans used 23 carbon compounds (12%) and 23 nitrogen compounds (24%). P. destructans exhibited more robust growth on the phosphorous compounds and nutrient supplements (83% and 15%, respectively) compared to P. pannorum (27% and 1%, respectively.). P. pannorum exhibited higher tolerance to osmolytes, pH extremes, and a variety of chemical compounds than P. destructans. Conclusions: An abundance of carbohydrate degradation pathways combined with robust stress tolerance provided clues for the soil distribution of P. pannorum. The limited metabolic profile of P. destructans was compatible with in silico predictions of far fewer proteins and enzymes. P. destructans ability to catabolize diverse phosphorous and nutrient supplements might be critical in the colonization and invasion of bat tissues. The present study of 1,047 different metabolic activities provides a framework for future gene-function investigations of the unique biology of the psychrophilic fungi.

Comparative studies on the effects of high-fat diet, endurance training and obesity on Ucp1 expression in male C57BL/6 mice

BackgroundObesity triggers a variety of severe conditions, therefore deteriorates metabolism rate of adipose tissues and muscles. Uncoupling proteins which are highly stimulated by fatty acids are potential targets for anti-obesity agents through breaking the electron gradient in the mitochondrial matrix and creating imbalances in the electron transport chain, thereby increasing the amount of substrate used to produce energy. Therefore, the aim of present study is assessment of exercise and high fat diet on expression level of Ucp1 subcutaneous white and brown adipose tissues (scWAT & BAT) respectively. MethodsTo perform experiments, 48 male C57BL/6 mice were divided to two major groups and fed with high fat diet (HFD) or low fat diet (LFD) during a period of 12 weeks. After the first intervention, each groups was divided into four groups randomly as (HF-EX), (HF-SED), (LF-EX), (LF-SED) [EX: exercise; SED: sedentary] in form of treadmill running for 45 min/day, 5 days/week during 8 weeks. One day after the last practice session, mice were sacrificed and Ucp1 expression was assessed on scWAT & BAT. ResultsData indicated a down-regulation in scWAT Ucp1 in obese mice similar to what observed for the expression of Pgc1α. Both, BAT Ucp1 and Pgc1α mRNA decreased significantly in response to obesity and physical activity. Moreover, exercise caused significant decrease in scWAT mitochondrial proteins contradictory to BAT. ConclusionTaken together, exercise exerted controversial effects compared with HFD and obesity on expression of Ucp1 and Pgc1α in scWAT dissimilar to BAT tissues, concluding that obesity may cause a resistance to exercise in terms of metabolic demands for scWAT tissue.

Phenotype profiling of white-nose syndrome pathogen Pseudogymnoascus destructans and closely-related Pseudogymnoascus pannorum reveals metabolic differences underlying fungal lifestyles.

Background:Pseudogymnoascusdestructans, a psychrophile, causes bat white-nose syndrome (WNS). Pseudogymnoascus pannorum, a closely related fungus, causes human and canine diseases rarely. Both pathogens were reported from the same mines and caves in the United States, but only P. destructans caused WNS. Earlier genome comparisons revealed that P. pannorum contained more deduced proteins with ascribed enzymatic functions than P. destructans. Methods: We performed metabolic profiling with Biolog PM microarray plates to confirm in silico gene predictions. Results:P. pannorum utilized 78 of 190 carbon sources (41%), and 41 of 91 nitrogen sources (43%) tested. P. destructans used 23 carbon compounds (12%) and 23 nitrogen compounds (24%). P. destructans exhibited more robust growth on the phosphorous sources and nutrient supplements (83% and 15%, respectively) compared to P. pannorum (27% and 1%, respectively.). P. pannorum exhibited higher tolerance to osmolytes, pH extremes, and a variety of chemical compounds than P. destructans. Conclusions: An abundance of carbohydrate degradation pathways combined with robust stress tolerance provided clues for the soil distribution of P. pannorum. The limited metabolic profile of P. destructans validated in silico predictions of far fewer proteins and enzymes. P. destructans ability to catabolize diverse phosphorous and nutrient supplements might be critical in the colonization and invasion of bat tissues. The present study of 1,047 different metabolic activities provides a framework for future gene-function investigations of the unique biology of the psychrophilic fungi.

Variation in Bat Guano Bacterial Community Composition With Depth.

Bats are known to be reservoirs for a variety of mammalian pathogens, including viruses, fungi, and bacteria. Many of the studies examining the microbial community inhabiting bats have investigated bacterial taxa found within specific bat tissues and isolated bat guano pellets, but relatively few studies have explored bacterial diversity within bat guano piles. In large bat caves, bat guano can accumulate over time, creating piles several meters deep and forming complex interactions with coprophagous organisms in a habitat with low light and oxygen. As the guano decays, the nutrient composition changes, but the bacterial communities deep within the pile have not been characterized. Here, we assess the bacterial communities across varying depths within the guano pile using both culture-independent and culture-dependent methods. We found that although similar taxa are found throughout the guano pile, the relative abundances of taxa within the pile shift, allowing certain taxa to dominate the bacterial community at varying depths. We also identified potential bacterial functions being performed within the bat guano as various depths within the pile and found little variation in terms of the dominant predicted functions, suggesting that although the relative abundances of bacterial taxa are changing, the functions being performed are similar. Additionally, we cultured 15 different bacterial species, including 2 not present in our culture-independent analysis, and discuss the pathogenicity potential of these taxa. This study represents the first characterization of the bacterial community from the extreme environment within a bat guano pile and demonstrates the potential for bat caves as resources for identifying new bacterial species.

DDT poisoning of big brown bats, Eptesicus fuscus, in Hamilton, Montana

Dichlorodiphenyltrichloroethane (DDT) is an insecticidal organochlorine pesticide with; known potential for neurotoxic effects in wildlife. The United States Environmental Protection Agency (US EPA) registration for this pesticide has been cancelled and there are currently no federally active products that contain this ingredient in the U.S. We present a case of a colony of big brown bats (E. Fuscus) found dead in the attic roost of an administrative building; in the city of Hamilton, Montana from unknown cause. DDT and its metabolites; dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) were detected in bat tissues by gas chromatography/mass spectrometry (GC-MS) and quantified by gas chromatography tandem quadrupole mass spectrometry (GC-MS/MS). Concentrations of 4081 ppm DDT and 890 ppm DDE wet weight were found in the brain of one bat and are the highest reported concentrations in such a mortality event to date. This case emphasizes the importance of testing wildlife mortalities against a comprehensive panel of toxicologic agents including persistent organic pollutants in the absence of other more common disease threats.