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Zhou Lan - One of the best experts on this subject based on the ideXlab platform.
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flavonoids extracted from Linaria vulgaris protect against hyperlipidemia and hepatic steatosis induced by western type diet in mice
Archives of Pharmacal Research, 2018Co-Authors: Wenhua Kuang, Xu Zhang, Zhou LanAbstract:Previous studies have shown that flavonoids (Fs) present in Linaria vulgaris inhibit lipid accumulation in vitro. This study was designed to evaluate the effects of Fs extracted from Linaria vulgaris ssp. sinensis (Bebeaux) Hong, on hyperlipidemia and hepatic steatosis induced by a western-type diet in mice. The major constituents of Fs were analyzed by LC–MS analysis. C57BL/6 mice were fed a western-type diet for 8 weeks to induce hyperlipidemia (model group), or fed a western-type diet followed by Fs treatment (90, 30 or 10 mg/kg/day) or atorvastatin treatment (1.0 mg/kg/day), for 8 weeks. It was found that Fs treatment resulted in significant reductions in serum levels of AST, ALT, TC, TG, LDL-C, free fatty acid and hepatic TC, and TG compared to those in model mice with hyperlipidemia (P < 0.05). The mice treated with Fs showed a relatively normal hepatic architecture compared to the hepatic steatosis shown in the model group. Moreover, the expressions of mature forms of sterol regulatory element–binding proteins (nuclear form of srebps, n-SREBPs) and 3-hydroxy-3-methylglutaryl coenzyme reductase (HMGCR) involved in lipid metabolism, were suppressed in the Fs-treated groups. Taken together, these results suggest Fs exert protective effects against hyperlipidemia and hepatic steatosis, which may involve the inhibition of mature SREBPs expressions.
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Flavonoids extracted from Linaria vulgaris protect against hyperlipidemia and hepatic steatosis induced by western-type diet in mice.
Archives of pharmacal research, 2017Co-Authors: Wenhua Kuang, Xu Zhang, Zhou LanAbstract:Previous studies have shown that flavonoids (Fs) present in Linaria vulgaris inhibit lipid accumulation in vitro. This study was designed to evaluate the effects of Fs extracted from Linaria vulgaris ssp. sinensis (Bebeaux) Hong, on hyperlipidemia and hepatic steatosis induced by a western-type diet in mice. The major constituents of Fs were analyzed by LC–MS analysis. C57BL/6 mice were fed a western-type diet for 8 weeks to induce hyperlipidemia (model group), or fed a western-type diet followed by Fs treatment (90, 30 or 10 mg/kg/day) or atorvastatin treatment (1.0 mg/kg/day), for 8 weeks. It was found that Fs treatment resulted in significant reductions in serum levels of AST, ALT, TC, TG, LDL-C, free fatty acid and hepatic TC, and TG compared to those in model mice with hyperlipidemia (P
Wenhua Kuang - One of the best experts on this subject based on the ideXlab platform.
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flavonoids extracted from Linaria vulgaris protect against hyperlipidemia and hepatic steatosis induced by western type diet in mice
Archives of Pharmacal Research, 2018Co-Authors: Wenhua Kuang, Xu Zhang, Zhou LanAbstract:Previous studies have shown that flavonoids (Fs) present in Linaria vulgaris inhibit lipid accumulation in vitro. This study was designed to evaluate the effects of Fs extracted from Linaria vulgaris ssp. sinensis (Bebeaux) Hong, on hyperlipidemia and hepatic steatosis induced by a western-type diet in mice. The major constituents of Fs were analyzed by LC–MS analysis. C57BL/6 mice were fed a western-type diet for 8 weeks to induce hyperlipidemia (model group), or fed a western-type diet followed by Fs treatment (90, 30 or 10 mg/kg/day) or atorvastatin treatment (1.0 mg/kg/day), for 8 weeks. It was found that Fs treatment resulted in significant reductions in serum levels of AST, ALT, TC, TG, LDL-C, free fatty acid and hepatic TC, and TG compared to those in model mice with hyperlipidemia (P < 0.05). The mice treated with Fs showed a relatively normal hepatic architecture compared to the hepatic steatosis shown in the model group. Moreover, the expressions of mature forms of sterol regulatory element–binding proteins (nuclear form of srebps, n-SREBPs) and 3-hydroxy-3-methylglutaryl coenzyme reductase (HMGCR) involved in lipid metabolism, were suppressed in the Fs-treated groups. Taken together, these results suggest Fs exert protective effects against hyperlipidemia and hepatic steatosis, which may involve the inhibition of mature SREBPs expressions.
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Flavonoids extracted from Linaria vulgaris protect against hyperlipidemia and hepatic steatosis induced by western-type diet in mice.
Archives of pharmacal research, 2017Co-Authors: Wenhua Kuang, Xu Zhang, Zhou LanAbstract:Previous studies have shown that flavonoids (Fs) present in Linaria vulgaris inhibit lipid accumulation in vitro. This study was designed to evaluate the effects of Fs extracted from Linaria vulgaris ssp. sinensis (Bebeaux) Hong, on hyperlipidemia and hepatic steatosis induced by a western-type diet in mice. The major constituents of Fs were analyzed by LC–MS analysis. C57BL/6 mice were fed a western-type diet for 8 weeks to induce hyperlipidemia (model group), or fed a western-type diet followed by Fs treatment (90, 30 or 10 mg/kg/day) or atorvastatin treatment (1.0 mg/kg/day), for 8 weeks. It was found that Fs treatment resulted in significant reductions in serum levels of AST, ALT, TC, TG, LDL-C, free fatty acid and hepatic TC, and TG compared to those in model mice with hyperlipidemia (P
Daniel A. Newman - One of the best experts on this subject based on the ideXlab platform.
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Interactions among nectar robbing, floral herbivory, and ant protection in Linaria vulgaris
2016Co-Authors: Daniel A. Newman, James D. ThomsonAbstract:herbivory, and ant protection in Linaria vulgaris. / Oikos 110: 497/506. Nectar robbers are often assumed to be plant antagonists; however, empirical data show that the impacts of these animals range from negative to positive depending on the system and ecological conditions. We experimentally evaluated the combined effects of nectar robbing and ant visitation on three indices of reproductive fitness in Linaria vulgaris in the Colorado Rocky Mountains, via indirect effects on flower- and seed-eating beetles (Brachypterolus pulicarius and Gymnaetron antirrhinni). Nectar robbing Bombus occidentalis leave holes in the nectar spurs, effectively creating ‘‘extra-floral nectaries’ ’ that attract ants. In a paired-plant experiment, ants were significantly more abundant on robbed than on unrobbed plants. Manipulation of ant access and nectar robbing showed that ant exclusion increased beetle attack and decreased female fitness. There was a significant ant-by-robbing interaction on flower damage. Patterns in the other two indices were suggestive of ant-by-robbing interactions, but these were not statistically significant. We also found correlations between spider occupancy on some plants and the mean number of ants (marginally negative) or beetles (significantly positive). Although the effect we report in this study may be highly dependent on spatial and temporal distributions of several interacting species, we discuss its potential role in mitigating the costs of floral parasitism, and its importance to the study of nectar robbing in general
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PREDICTING THE EFFECTS OF NECTAR ROBBING ON PLANT REPRODUCTION: IMPLICATIONS OF POLLEN LIMITATION AND PLANT MATING SYSTEM
2014Co-Authors: Laura A. Burkle, Rebecca E. Irwin, Daniel A. NewmanAbstract:The outcome of species interactions is often difficult to predict, depending on the organisms involved and the ecological context. Nectar robbers remove nectar from flowers, often without providing pollination service, and their effects on plant reproduction vary in strength and direction. In two case studies and a meta-analysis, we tested the importance of pollen limitation and plant mating system in predicting the impacts of nectar robbing on female plant reproduction. We predicted that nectar robbing would have the strongest effects on species requiring pollinators to set seed and pollen limited for seed production. Our predictions were partially supported. In the first study, natural nectar robbing was associated with lower seed production in Delphinium nuttallianum, a self-compatible but non-autogamously selfing, pollen-limited perennial, and experimental nectar robbing reduced seed set relative to unrobbed plants. The second study involved Linaria vulgaris, a self-incompatible perennial that is generally not pollen limited. Natural levels of nectar robbing generally had little effect on estimates of female reproduction in L. vulgaris, while experimental nectar robbing reduced seed set per fruit but not percentage of fruit set. A meta-analysis revealed that nectar robbing had strong negative effects on pollen-limited and self-incompatible plants, as predicted. Our results suggest that pollination biology and plant mating system must be considered to understand and predict the ecological outcome of both mutualistic and antagonistic plant–animal interactions. Key words: Bombus occidentalis; Colorado; Delphinium nuttallianum; Linaria vulgaris; meta-analysis; nectar robbing; pollen limitation; self-compatibility
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Interactions among nectar robbing, floral herbivory, and ant protection in Linaria vulgaris
Oikos, 2005Co-Authors: Daniel A. Newman, James D. ThomsonAbstract:Nectar robbers are often assumed to be plant antagonists; however, empirical data show that the impacts of these animals range from negative to positive depending on the system and ecological conditions. We experimentally evaluated the combined effects of nectar robbing and ant visitation on three indices of reproductive fitness in Linaria vulgaris in the Colorado Rocky Mountains, via indirect effects on flower- and seed-eating beetles (Brachypterolus pulicarius and Gymnaetron antirrhinni). Nectar robbing Bombus occidentalis leave holes in the nectar spurs, effectively creating “extra-floral nectaries” that attract ants. In a paired-plant experiment, ants were significantly more abundant on robbed than on unrobbed plants. Manipulation of ant access and nectar robbing showed that ant exclusion increased beetle attack and decreased female fitness. There was a significant ant-by-robbing interaction on flower damage. Patterns in the other two indices were suggestive of ant-by-robbing interactions, but these were not statistically significant. We also found correlations between spider occupancy on some plants and the mean number of ants (marginally negative) or beetles (significantly positive). Although the effect we report in this study may be highly dependent on spatial and temporal distributions of several interacting species, we discuss its potential role in mitigating the costs of floral parasitism, and its importance to the study of nectar robbing in general.
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Effects of nectar robbing on nectar dynamics and bumblebee foraging strategies in Linaria vulgaris (Scrophulariaceae)
Oikos, 2005Co-Authors: Daniel A. Newman, James D. ThomsonAbstract:Differences in morphology among bumblebee species sharing a nectar resource may lead to variation in foraging behaviour and efficiency. Less efficient bumblebees might opportunistically switch foraging strategies from legitimate visitation to secondary robbing when hole-biting primary robbers are present. We observed various aspects of pollination and nectar robbing ecology of Linaria vulgaris in the Colorado Rocky Mountains, with emphasis on the role of bumblebee proboscis length. Bees can extract nectar from a nectar spur legitimately, by entering the front of the flower, or illegitimately, by biting or reusing holes in the spur. Although L. vulgaris flowers are apparently adapted for pollination by long-tongued bees, short-tongued bees visited them legitimately for trace amounts of nectar but switched to secondary robbing in the presence of primary robbers. Longer-tongued bees removed more nectar in less time than did shorter-tongued bees, and were less likely to switch to secondary robbing even when ∼100% of flowers had been pierced. As the proportion of robbed flowers in the population increased, the relative number of legitimate visits decreased while the relative number of robbing visits increased. Robbing decreased nectar standing crop and increased the proportion of empty flowers per inflorescence. Despite these potentially detrimental effects of robbers, differences in inflorescence use among robbers and pollinators, and the placement of holes made by primary robbers, may mitigate negative effects of nectar robbing in L. vulgaris. We discuss some of the reasons that L. vulgaris pollination ecology and growth form might temper the potentially negative effect of nectar robbing.
James D. Thomson - One of the best experts on this subject based on the ideXlab platform.
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Interactions among nectar robbing, floral herbivory, and ant protection in Linaria vulgaris
2016Co-Authors: Daniel A. Newman, James D. ThomsonAbstract:herbivory, and ant protection in Linaria vulgaris. / Oikos 110: 497/506. Nectar robbers are often assumed to be plant antagonists; however, empirical data show that the impacts of these animals range from negative to positive depending on the system and ecological conditions. We experimentally evaluated the combined effects of nectar robbing and ant visitation on three indices of reproductive fitness in Linaria vulgaris in the Colorado Rocky Mountains, via indirect effects on flower- and seed-eating beetles (Brachypterolus pulicarius and Gymnaetron antirrhinni). Nectar robbing Bombus occidentalis leave holes in the nectar spurs, effectively creating ‘‘extra-floral nectaries’ ’ that attract ants. In a paired-plant experiment, ants were significantly more abundant on robbed than on unrobbed plants. Manipulation of ant access and nectar robbing showed that ant exclusion increased beetle attack and decreased female fitness. There was a significant ant-by-robbing interaction on flower damage. Patterns in the other two indices were suggestive of ant-by-robbing interactions, but these were not statistically significant. We also found correlations between spider occupancy on some plants and the mean number of ants (marginally negative) or beetles (significantly positive). Although the effect we report in this study may be highly dependent on spatial and temporal distributions of several interacting species, we discuss its potential role in mitigating the costs of floral parasitism, and its importance to the study of nectar robbing in general
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Interactions among nectar robbing, floral herbivory, and ant protection in Linaria vulgaris
Oikos, 2005Co-Authors: Daniel A. Newman, James D. ThomsonAbstract:Nectar robbers are often assumed to be plant antagonists; however, empirical data show that the impacts of these animals range from negative to positive depending on the system and ecological conditions. We experimentally evaluated the combined effects of nectar robbing and ant visitation on three indices of reproductive fitness in Linaria vulgaris in the Colorado Rocky Mountains, via indirect effects on flower- and seed-eating beetles (Brachypterolus pulicarius and Gymnaetron antirrhinni). Nectar robbing Bombus occidentalis leave holes in the nectar spurs, effectively creating “extra-floral nectaries” that attract ants. In a paired-plant experiment, ants were significantly more abundant on robbed than on unrobbed plants. Manipulation of ant access and nectar robbing showed that ant exclusion increased beetle attack and decreased female fitness. There was a significant ant-by-robbing interaction on flower damage. Patterns in the other two indices were suggestive of ant-by-robbing interactions, but these were not statistically significant. We also found correlations between spider occupancy on some plants and the mean number of ants (marginally negative) or beetles (significantly positive). Although the effect we report in this study may be highly dependent on spatial and temporal distributions of several interacting species, we discuss its potential role in mitigating the costs of floral parasitism, and its importance to the study of nectar robbing in general.
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Effects of nectar robbing on nectar dynamics and bumblebee foraging strategies in Linaria vulgaris (Scrophulariaceae)
Oikos, 2005Co-Authors: Daniel A. Newman, James D. ThomsonAbstract:Differences in morphology among bumblebee species sharing a nectar resource may lead to variation in foraging behaviour and efficiency. Less efficient bumblebees might opportunistically switch foraging strategies from legitimate visitation to secondary robbing when hole-biting primary robbers are present. We observed various aspects of pollination and nectar robbing ecology of Linaria vulgaris in the Colorado Rocky Mountains, with emphasis on the role of bumblebee proboscis length. Bees can extract nectar from a nectar spur legitimately, by entering the front of the flower, or illegitimately, by biting or reusing holes in the spur. Although L. vulgaris flowers are apparently adapted for pollination by long-tongued bees, short-tongued bees visited them legitimately for trace amounts of nectar but switched to secondary robbing in the presence of primary robbers. Longer-tongued bees removed more nectar in less time than did shorter-tongued bees, and were less likely to switch to secondary robbing even when ∼100% of flowers had been pierced. As the proportion of robbed flowers in the population increased, the relative number of legitimate visits decreased while the relative number of robbing visits increased. Robbing decreased nectar standing crop and increased the proportion of empty flowers per inflorescence. Despite these potentially detrimental effects of robbers, differences in inflorescence use among robbers and pollinators, and the placement of holes made by primary robbers, may mitigate negative effects of nectar robbing in L. vulgaris. We discuss some of the reasons that L. vulgaris pollination ecology and growth form might temper the potentially negative effect of nectar robbing.
Rosa M. Seabra - One of the best experts on this subject based on the ideXlab platform.
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Assessing the antioxidative properties and chemical composition of Linaria vulgaris infusion.
Natural product research, 2008Co-Authors: Vendula Vrchovská, Jiřina Spilková, Patrícia Valentão, Carla Sousa, Paula B. Andrade, Rosa M. SeabraAbstract:The ability of Linaria vulgaris (Scrophulariaceae) infusion to act as a scavenger of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, reactive oxygen species (superoxide radical, hydroxyl radical, hypochlorous acid (HOCl)) and nitric oxide was investigated. The obtained data indicate that the infusion has a good scavenging activity against superoxide radical and is a very potent nitric oxide and DPPH scavenger. In hydroxyl radical assay a pro-oxidant capacity was noticed, especially for concentrations higher than 31.25 µg mL−1. No effect was found against HOCl. A phytochemical study of this extract was also performed. The HPLC/UV analysis allowed the identification and quantification of eight organic acids (oxalic, aconitic, citric, ketoglutaric, ascorbic, malic, shikimic and fumaric acids). The phenolic composition of the lyophilised infusion was also determined by HPLC/DAD and four compounds were quantified, but, despite its high content, only linarin was managed to be identified.