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Mayumi Ishizuka - One of the best experts on this subject based on the ideXlab platform.
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Uridine Diphosphate-Glucuronosyltransferase (UGT) 2B Subfamily Interspecies Differences in Carnivores.
Toxicological sciences : an official journal of the Society of Toxicology, 2017Co-Authors: Takamitsu Kondo, Yoshinori Ikenaka, Shouta M.m. Nakayama, Yusuke K. Kawai, Hazuki Mizukawa, Yoko Mitani, Kei Nomiyama, Shinsuke Tanabe, Mayumi IshizukaAbstract:UDP-glucuronosyltransferases (UGTs) are among the most important xenobiotic metabolizing enzymes that conjugate a wide range of chemicals. Previous studies showed that Felidae and Pinnipedia species have very low UGT activities toward some phenolic compounds because of the UGT1A6 pseudogene and small numbers of UGT1A isozymes. In addition to the UGT1As, UGT2Bs isozymes also conjugate various endogenous (eg, estrogens, androgens, and bile acids) and exogenous compounds (opioids, non-steroidal anti-inflammatory drugs, and environmental pollutants). However UGT2B activity and genetic background are unknown in carnivore species. Therefore, this study was performed to elucidate the species differences of UGT2Bs. Using typical substrates for UGT2Bs, UGT activity was measured in vitro. In addition, UGT2B genetic features are analyzed in silico. Results of UGT activity measurement indicate marked species differences between dogs and other carnivores (cats, Northern fur seals, Steller sea lions, Harbor seals, and Caspian seals). Dogs have very high Vmax/Km toward estradiol (17-glucuronide), estrone, lorazepam, oxazepam, and temazepam. Conversely, cats and pinniped species (especially Caspian seals and Harbor seals) have very low activities toward these substrates. The results of genetic synteny analysis indicate that Felidae and pinniped species have very small numbers of UGT2B isozymes (one or none) compared with dogs, rodents, and humans. Furthermore, Felidae species have the same nonsense mutation in UGT2B, which suggests that Felidae UGT2B31-like is also a pseudogene in addition to UGT1A6. These findings of lower activity of UGT2B suggest that Felidae and some pinniped species have very low UGT activity toward a wide range of chemicals. These results are important for Felidae and Pinnipedia species that are frequently exposed to drugs and environmental pollutants.
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uridine diphosphate glucuronosyltransferase ugt xenobiotic metabolizing activity and genetic evolution in pinniped species
Toxicological Sciences, 2015Co-Authors: Mayu Kakehi, Yoshinori Ikenaka, Shouta M.m. Nakayama, Yusuke K. Kawai, Hazuki Mizukawa, Kei Nomiyama, Shinsuke Tanabe, Kensuke P Watanabe, Mayumi IshizukaAbstract:There are various interspecies differences in xenobiotic-metabolizing enzymes. It is known that cats show slow glucuronidation of drugs such as acetaminophen and strong side effects due to the UGT1A6 pseudogene. Recently, the UGT1A6 pseudogene was found in the Northern elephant seal and Otariidae was suggested to be UGT1A6-deficient. From the results of measurements of uridine diphosphate-glucuronosyltransferase (UGT) activity using liver microsomes, the Steller sea lion, Northern fur seal, and Caspian seal showed UGT activity toward 1-hydroxypyrene and acetaminophen as low as in cats, which was significantly lower than in rat and dog. Furthermore, UGT1A6 pseudogenes were found in Steller sea lion and Northern fur seal, and all Otariidae species were suggested to have the UGT1A6 pseudogene. The UGT1 family genes appear to have undergone birth-and-death evolution based on a phylogenetic and synteny analysis of the UGT1 family in mammals including Carnivora. UGT1A2-1A5 and UGT1A7-1A10 are paralogous genes to UGT1A1 and UGTA6, respectively, and their numbers were lower in cat, ferret and Pacific walrus than in human, rat, and dog. Felidae and Pinnipedia, which are less exposed to natural xenobiotics such as plant-derived toxins due to their carnivorous diet, have experienced fewer gene duplications of xenobiotic-metabolizing UGT genes, and even possess UGT1A6 pseudogenes. Artificial environmental pollutants and drugs conjugated by UGT are increasing dramatically, and their elimination to the environment can be of great consequence to cat and Pinnipedia species, whose low xenobiotic glucuronidation capacity makes them highly sensitive to these compounds.
Yoshinori Ikenaka - One of the best experts on this subject based on the ideXlab platform.
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Uridine Diphosphate-Glucuronosyltransferase (UGT) 2B Subfamily Interspecies Differences in Carnivores.
Toxicological sciences : an official journal of the Society of Toxicology, 2017Co-Authors: Takamitsu Kondo, Yoshinori Ikenaka, Shouta M.m. Nakayama, Yusuke K. Kawai, Hazuki Mizukawa, Yoko Mitani, Kei Nomiyama, Shinsuke Tanabe, Mayumi IshizukaAbstract:UDP-glucuronosyltransferases (UGTs) are among the most important xenobiotic metabolizing enzymes that conjugate a wide range of chemicals. Previous studies showed that Felidae and Pinnipedia species have very low UGT activities toward some phenolic compounds because of the UGT1A6 pseudogene and small numbers of UGT1A isozymes. In addition to the UGT1As, UGT2Bs isozymes also conjugate various endogenous (eg, estrogens, androgens, and bile acids) and exogenous compounds (opioids, non-steroidal anti-inflammatory drugs, and environmental pollutants). However UGT2B activity and genetic background are unknown in carnivore species. Therefore, this study was performed to elucidate the species differences of UGT2Bs. Using typical substrates for UGT2Bs, UGT activity was measured in vitro. In addition, UGT2B genetic features are analyzed in silico. Results of UGT activity measurement indicate marked species differences between dogs and other carnivores (cats, Northern fur seals, Steller sea lions, Harbor seals, and Caspian seals). Dogs have very high Vmax/Km toward estradiol (17-glucuronide), estrone, lorazepam, oxazepam, and temazepam. Conversely, cats and pinniped species (especially Caspian seals and Harbor seals) have very low activities toward these substrates. The results of genetic synteny analysis indicate that Felidae and pinniped species have very small numbers of UGT2B isozymes (one or none) compared with dogs, rodents, and humans. Furthermore, Felidae species have the same nonsense mutation in UGT2B, which suggests that Felidae UGT2B31-like is also a pseudogene in addition to UGT1A6. These findings of lower activity of UGT2B suggest that Felidae and some pinniped species have very low UGT activity toward a wide range of chemicals. These results are important for Felidae and Pinnipedia species that are frequently exposed to drugs and environmental pollutants.
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uridine diphosphate glucuronosyltransferase ugt xenobiotic metabolizing activity and genetic evolution in pinniped species
Toxicological Sciences, 2015Co-Authors: Mayu Kakehi, Yoshinori Ikenaka, Shouta M.m. Nakayama, Yusuke K. Kawai, Hazuki Mizukawa, Kei Nomiyama, Shinsuke Tanabe, Kensuke P Watanabe, Mayumi IshizukaAbstract:There are various interspecies differences in xenobiotic-metabolizing enzymes. It is known that cats show slow glucuronidation of drugs such as acetaminophen and strong side effects due to the UGT1A6 pseudogene. Recently, the UGT1A6 pseudogene was found in the Northern elephant seal and Otariidae was suggested to be UGT1A6-deficient. From the results of measurements of uridine diphosphate-glucuronosyltransferase (UGT) activity using liver microsomes, the Steller sea lion, Northern fur seal, and Caspian seal showed UGT activity toward 1-hydroxypyrene and acetaminophen as low as in cats, which was significantly lower than in rat and dog. Furthermore, UGT1A6 pseudogenes were found in Steller sea lion and Northern fur seal, and all Otariidae species were suggested to have the UGT1A6 pseudogene. The UGT1 family genes appear to have undergone birth-and-death evolution based on a phylogenetic and synteny analysis of the UGT1 family in mammals including Carnivora. UGT1A2-1A5 and UGT1A7-1A10 are paralogous genes to UGT1A1 and UGTA6, respectively, and their numbers were lower in cat, ferret and Pacific walrus than in human, rat, and dog. Felidae and Pinnipedia, which are less exposed to natural xenobiotics such as plant-derived toxins due to their carnivorous diet, have experienced fewer gene duplications of xenobiotic-metabolizing UGT genes, and even possess UGT1A6 pseudogenes. Artificial environmental pollutants and drugs conjugated by UGT are increasing dramatically, and their elimination to the environment can be of great consequence to cat and Pinnipedia species, whose low xenobiotic glucuronidation capacity makes them highly sensitive to these compounds.
Anjali Goswami - One of the best experts on this subject based on the ideXlab platform.
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Impact of the terrestrial-aquatic transition on disparity and rates of evolution in the carnivoran skull
BMC Evolutionary Biology, 2015Co-Authors: Katrina E Jones, Jeroen B Smaers, Anjali GoswamiAbstract:Background Which factors influence the distribution patterns of morphological diversity among clades? The adaptive radiation model predicts that a clade entering new ecological niche will experience high rates of evolution early in its history, followed by a gradual slowing. Here we measure disparity and rates of evolution in Carnivora, specifically focusing on the terrestrial-aquatic transition in Pinnipedia. We analyze fissiped (mostly terrestrial, arboreal, and semi-arboreal, but also including the semi-aquatic otter) and pinniped (secondarily aquatic) carnivorans as a case study of an extreme ecological transition. We used 3D geometric morphometrics to quantify cranial shape in 151 carnivoran specimens (64 fissiped, 87 pinniped) and five exceptionally-preserved fossil pinnipeds, including the stem-pinniped Enaliarctos emlongi . Range-based and variance-based disparity measures were compared between pinnipeds and fissipeds. To distinguish between evolutionary modes, a Brownian motion model was compared to selective regime shifts associated with the terrestrial-aquatic transition and at the base of Pinnipedia. Further, evolutionary patterns were estimated on individual branches using both Ornstein-Uhlenbeck and Independent Evolution models, to examine the origin of pinniped diversity. Results Pinnipeds exhibit greater cranial disparity than fissipeds, even though they are less taxonomically diverse and, as a clade nested within fissipeds, phylogenetically younger. Despite this, there is no increase in the rate of morphological evolution at the base of Pinnipedia, as would be predicted by an adaptive radiation model, and a Brownian motion model of evolution is supported. Instead basal pinnipeds populated new areas of morphospace via low to moderate rates of evolution in new directions, followed by later bursts within the crown-group, potentially associated with ecological diversification within the marine realm. Conclusion The transition to an aquatic habitat in carnivorans resulted in a shift in cranial morphology without an increase in rate in the stem lineage, contra to the adaptive radiation model. Instead these data suggest a release from evolutionary constraint model, followed by aquatic diversifications within crown families.
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Impact of the terrestrial-aquatic transition on disparity and rates of evolution in the carnivoran skull.
BMC evolutionary biology, 2015Co-Authors: Katrina E Jones, Jeroen B Smaers, Anjali GoswamiAbstract:Which factors influence the distribution patterns of morphological diversity among clades? The adaptive radiation model predicts that a clade entering new ecological niche will experience high rates of evolution early in its history, followed by a gradual slowing. Here we measure disparity and rates of evolution in Carnivora, specifically focusing on the terrestrial-aquatic transition in Pinnipedia. We analyze fissiped (mostly terrestrial, arboreal, and semi-arboreal, but also including the semi-aquatic otter) and pinniped (secondarily aquatic) carnivorans as a case study of an extreme ecological transition. We used 3D geometric morphometrics to quantify cranial shape in 151 carnivoran specimens (64 fissiped, 87 pinniped) and five exceptionally-preserved fossil pinnipeds, including the stem-pinniped Enaliarctos emlongi. Range-based and variance-based disparity measures were compared between pinnipeds and fissipeds. To distinguish between evolutionary modes, a Brownian motion model was compared to selective regime shifts associated with the terrestrial-aquatic transition and at the base of Pinnipedia. Further, evolutionary patterns were estimated on individual branches using both Ornstein-Uhlenbeck and Independent Evolution models, to examine the origin of pinniped diversity. Pinnipeds exhibit greater cranial disparity than fissipeds, even though they are less taxonomically diverse and, as a clade nested within fissipeds, phylogenetically younger. Despite this, there is no increase in the rate of morphological evolution at the base of Pinnipedia, as would be predicted by an adaptive radiation model, and a Brownian motion model of evolution is supported. Instead basal pinnipeds populated new areas of morphospace via low to moderate rates of evolution in new directions, followed by later bursts within the crown-group, potentially associated with ecological diversification within the marine realm. The transition to an aquatic habitat in carnivorans resulted in a shift in cranial morphology without an increase in rate in the stem lineage, contra to the adaptive radiation model. Instead these data suggest a release from evolutionary constraint model, followed by aquatic diversifications within crown families.
Mayu Kakehi - One of the best experts on this subject based on the ideXlab platform.
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uridine diphosphate glucuronosyltransferase ugt xenobiotic metabolizing activity and genetic evolution in pinniped species
Toxicological Sciences, 2015Co-Authors: Mayu Kakehi, Yoshinori Ikenaka, Shouta M.m. Nakayama, Yusuke K. Kawai, Hazuki Mizukawa, Kei Nomiyama, Shinsuke Tanabe, Kensuke P Watanabe, Mayumi IshizukaAbstract:There are various interspecies differences in xenobiotic-metabolizing enzymes. It is known that cats show slow glucuronidation of drugs such as acetaminophen and strong side effects due to the UGT1A6 pseudogene. Recently, the UGT1A6 pseudogene was found in the Northern elephant seal and Otariidae was suggested to be UGT1A6-deficient. From the results of measurements of uridine diphosphate-glucuronosyltransferase (UGT) activity using liver microsomes, the Steller sea lion, Northern fur seal, and Caspian seal showed UGT activity toward 1-hydroxypyrene and acetaminophen as low as in cats, which was significantly lower than in rat and dog. Furthermore, UGT1A6 pseudogenes were found in Steller sea lion and Northern fur seal, and all Otariidae species were suggested to have the UGT1A6 pseudogene. The UGT1 family genes appear to have undergone birth-and-death evolution based on a phylogenetic and synteny analysis of the UGT1 family in mammals including Carnivora. UGT1A2-1A5 and UGT1A7-1A10 are paralogous genes to UGT1A1 and UGTA6, respectively, and their numbers were lower in cat, ferret and Pacific walrus than in human, rat, and dog. Felidae and Pinnipedia, which are less exposed to natural xenobiotics such as plant-derived toxins due to their carnivorous diet, have experienced fewer gene duplications of xenobiotic-metabolizing UGT genes, and even possess UGT1A6 pseudogenes. Artificial environmental pollutants and drugs conjugated by UGT are increasing dramatically, and their elimination to the environment can be of great consequence to cat and Pinnipedia species, whose low xenobiotic glucuronidation capacity makes them highly sensitive to these compounds.
Annalisa Berta - One of the best experts on this subject based on the ideXlab platform.
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The evolution of feeding strategies in phocid seals (Pinnipedia, Phocidae)
2019Co-Authors: Sarah S. Kienle, Annalisa BertaAbstract:Adaptations for feeding underwater were crucial to the success of pinnipeds (seals, sea lions, and walruses) in their transition from terrestrial to aquatic habitats. Extant phocids (true seals) use multiple feeding strategies—biting, filter, and suction feeding—to capture and consume prey, and each strategy is associated with cranial, mandibular, and dental adaptations. However, little is known about feeding strategies in stem pinnipeds. The objectives of this study were to investigate feeding strategies used by some extinct pinnipeds based on cranial and mandibular morphologies and use this framework to examine the evolution of phocid feeding strategies. Three-dimensional cranial and mandibular landmark data were collected from 249 extant and fossil pinnipeds. Principal component analysis and canonical variate analysis were performed to describe the major axes of variation and compare overlap of fossil and extant taxa in morphospace. Stem pinnipeds had morphologies associated with biting and filter feeding. Several fossil taxa were most similar to extant biters, suggesting that biting was a common and important feeding strategy for early phocids. One fossil taxon, Homiphoca capensis, was potentially a filter feeder, because it consistently overlapped with extant filter feeders in cranial morphospace. No fossil taxa had morphological adaptations for suction feeding, indicating that suction feeding is a more derived strategy in phocids. Extant phocids and their ancestors have cranial and mandibular adaptations for multiple feeding strategies, which allowed these animals to move into diverse aquatic niches and likely contributed to their successful transition from terrestrial to aquatic ecosystems.
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the evolution of feeding strategies in phocid seals Pinnipedia phocidae
Journal of Vertebrate Paleontology, 2018Co-Authors: Sarah S. Kienle, Annalisa BertaAbstract:ABSTRACTAdaptations for feeding underwater were crucial to the success of pinnipeds (seals, sea lions, and walruses) in their transition from terrestrial to aquatic habitats. Extant phocids (true s...
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The evolution of feeding strategies in phocid seals (Pinnipedia, Phocidae)
Journal of Vertebrate Paleontology, 2018Co-Authors: Sarah S. Kienle, Annalisa BertaAbstract:Adaptations for feeding underwater were crucial to the success of pinnipeds (seals, sea lions, and walruses) in their transition from terrestrial to aquatic habitats. Extant phocids (true seals) us...