22 research outputs found
KENYAN PURPLE TEA ANTHOCYANINS ABILITY TO CROSS THE BLOOD BRAIN BARRIER REINFORCING BRAIN ANTIOXIDANT CAPACITY IN MICE
Studies on antioxidants as neuroprotective agents have been hampered by
the impermeability of the blood brain barrier (BBB) to many compounds.
However, previous studies have shown that a group of tea ( Camellia
sinensis ) flavonoids, the catechins, are brain permeable and
neuroprotective. Despite this remarkable observation, there exists no
data on the bioavailability and pharmacological benefits of tea
anthocyanins (ACNs) in the brain tissue. This study investigated the
ability of Kenyan purple tea ACNs to cross the BBB and boost the brain
antioxidant capacity. Mice were orally administered with purified and
characterised Kenyan purple tea ACNs or a combination of Kenyan purple
tea ACN\u2019s and coenzyme-Q10, at a dose of 200 mg kg-1 body weight
in an experiment that lasted for 15 days. Twenty four hours post the
last dosage of antioxidants, CO2 was used to euthenise the mice. Then
the brain was excised and used for various biochemical analyses. Kenyan
purple tea ACNs significantly (P<0.05) raised brain Glutathione
(GSH) levels, implying a boost in brain antioxidant capacity. Notably,
ACN metabolites were detected in brain tissue of ACN fed mice. This is
the first demonstration that Kenyan purple tea ACNs can cross the BBB,
reinforcing the brain\u2019s antioxidant capacity. Hence, there is
need to study ACNs as suitable candidates for dietary supplements that
could support antioxidant capacity in the brain and have potential to
provide neuroprotection in neurodegenerative conditions.Les \ue9tudes sur les antioxydants comme agents neuroprotecteurs ont
\ue9t\ue9 handicap\ue9es par l\u2019imperm\ue9abilit\ue9 de
la barri\ue8re de sang du cerveau (BBB) \ue0 plusieurs produits.
Par ailleurs, les \ue9tudes ant\ue9rieurs ont montr\ue9
qu\u2019un groupe de flavono\uefdes du th\ue9 ( Camellia sinensis
) , les cat\ue9chines, permettent la perm\ue9abilit\ue9 du
cerveau et prot\ue8gent les nerfs. Malgr\ue9 cette observation
importante, il n\u2019ya pas de donn\ue9es sur la
biodisponibilit\ue9 et les vertus pharmacologiques des anthocyanines
du th\ue9 (ACNs) dans le tissue du cerveau. Cette \ue9tude a
\ue9valu\ue9 l\u2019aptitude des anthocyanines du th\ue9 pourpre
du Kenya de traverser le BBB et am\ue9liorer la capacit\ue9
antioxydante du cerveau. Des rats \ue9taient oralement
administr\ue9s des anthocianines du th\ue9 pourpre purifi\ue9s et
caract\ue9ris\ue9s ou une combinaison des ACNs avec le
coenzyme-Q10, \ue0 une dose de 200 mg kg-1 de poids vif dans un essai
d\u2019une dur\ue9e de 15 jours. Vingt quatre heures apr\ue8s le
dernier dosage d\u2019antioxydants, le CO2 \ue9tait utilis\ue9
pour euthanasier les rats. Ensuite, le cerveau \ue9tait excis\ue9
et soumis \ue0 diverses analyses biochimiques. Les ACNs ont
augment\ue9 significativement (P<0.05) les niveaux du Glutathione
(GSH) du cerveau,,ce qui implique une am\ue9lioration de la
capacit\ue9 antioxydante du cerveau. Remarquablement, les
m\ue9tabolites ACN \ue9taient d\ue9tect\ue9s dans le tissu des
rats nourris aux ACNs. Ceci est la premi\ue8re d\ue9monstration que
les anthocyanines (ACNs) du th\ue9 pourpre Kenyan peuvent franchir la
barri\ue8re h\ue9mato-enc\ue9phalique (BHE), renfor\ue7ant
ainsi la capacit\ue9 antioxydante du cerveau. Ainsi, le besoin
s\u2019impose de les \ue9tudier comme des candidats appropri\ue9s
pour les aliments de suppl\ue9ment qui pourraient renforcer la
capacit\ue9 antioxydante dans le cerveau et avoir le potentiel
d\u2019offrir la neuroprotection dans les conditions
neurod\ue9g\ue9n\ue9ratrices
Revealing hidden species distribution with pheromones: the case of Synanthedon vespiformis (Lepidoptera: Sesiidae) in Sweden
Synanthedon vespiformis L. (Lepidoptera: Sesiidae) is considered a rare insect in Sweden, discovered in 1860, with only a few observations recorded until a sex pheromone attractant became available recently. This study details a national survey conducted using pheromones as a sampling method for this species. Through pheromone trapping we captured 439 specimens in Southern Sweden at 77 sites, almost tripling the number of previously reported records for this species. The results suggest that S. vespiformis is truly a rare species with a genuinely scattered distribution, but can be locally abundant. Habitat analyses were conducted in order to test the relationship between habitat quality and the number of individuals caught. In Sweden, S. vespiformis is thought to be associated with oak hosts, but our attempts to predict its occurrence by the abundance of oaks yielded no significant relationships. We therefore suggest that sampling bias and limited knowledge on distribution may have led to the assumption that this species is primarily reliant on oaks in the northern part of its range, whereas it may in fact be polyphagous, similar to S. vespiformis found as an agricultural pest in Central and Southern Europe. We conclude that pheromones can massively enhance sampling potential for this and other rare lepidopteran species. Large-scale pheromone-based surveys provide a snapshot of true presences and absences across a considerable part of a species national distribution range, and thus for the first time provide a viable means of systematically assessing changes in distribution over time with high spatiotemporal resolution
Data from: Stay at home aphids: comparative spatial and seasonal metapopulation structure and dynamics of two specialist tansy aphid species studied using microsatellite markers
Two tansy-feeding aphids – Macrosiphoniella tanacetaria (MA) and Metopeurum fuscoviride (ME) – were studied at a small spatial scale in and around Jena (< 80 km2) using polymorphic microsatellite markers. Both species were found in ~ 60% of sites formerly known to harbour the aphids, although generally when they did occur, they occurred singly (MA ~ 50%; ME ~60%) and rarely together on the same plant at the same time (~10%) and then usually only in the early part of the growing season. This difference may be due to quasi-apparent competition effects elicited to ants farming ME aphids, and preferentially actively eliminating or disturbing MA aphids. In terms of population genetics, both aphids showed extreme genetic heterogeneity within a metapopulation structure, ME more than MA, i.e. higher FST values, ~ 0.4 vs. 0.15, respectively, and limited levels of interpopulation gene flow. Subpopulations often deviated from Hardy-Weinberg equilibrium and showed linkage disequilibria, as expected in animals with extended parthenogenetic reproduction, and had positive FIS values for most large samples, suggesting inbreeding, and possibly philopatry, certainly in ME. Hierarchical analysis (allele range and number per locus, analysis of molecular variance and FST) strongly suggested that the plant rather than site governs the level of genetic variation. Bayesian clustering analysis revealed that both species had heterogeneous historical genetic patterning, with K (number of subgroups) ranging from 3-7. Evidence is also provided from isolation by distance (IBD) and private allele analyses, that in MA, the presence of winged autumn males, absent in ME where males are wingless, influences comparative population genetic structuring, such that ME subpopulations are comparatively more inbred and genetically differentiated than MA subpopulations. Lastly, additional spatial arrangement (ALLELES-IN-SPACE) analysis showed that in both species, certain subpopulations were genetically isolated from the remainder, probably due to geographical barriers, including intervening buildings and woods. As such, the biology of these tansy aphids living in semi-natural habitats is very different from many pest aphid species examined within agro-ecosystems and infesting ephemeral crops, since the former seem much more reluctant to fly and hence show contrastingly much higher levels of interpopulation divergence, even at small spatial scales as here investigated. Indeed, the number of genotypic clusters found for tansy aphids found using Bayesian approaches is similar to that for the major pest the peach-potato aphid, Myzus persicae, globally
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Common Cerambycid Pheromone Components as Attractants for Longhorn Beetles (Cerambycidae) Breeding in Ephemeral Oak Substrates in Northern Europe
Longhorn beetles are ecologically important insects in forest ecosystems as decomposers of woody substrates, microhabitat engineers, and as components of forest food webs. These species can be greatly affected both positively and negatively by modern forestry management practices, and should be monitored accordingly. Through headspace sampling, coupled gas chromatography-electroantennography, gas chromatography-mass spectrometry, and field bioassays, we identified two compounds, 2-methyl-1-butanol and 3-hydroxy-2-hexanone, that constitute aggregation-sex pheromone attractants of three cerambycid species which breed primarily in different types of fresh, recently dead oak wood in Northern Europe: Pyrrhidium sanguineum (L.), Phymatodes alni ssp. alni (L.), and Phymatodes testaceus (L.) (Cerambycinae: Callidiini). Analyses of headspace volatiles collected from live insects indicated that the male-produced aggregation-sex pheromone of P. sanguineum is a 1-15:100 blend of (R)-2-methyl-1-butanol and (R)-3-hydroxy-2-hexanone, whereas the corresponding ratios for P. alni were 70-110:100. In field bioassays, adult P. sanguineum and P. alni were significantly attracted to multiple blends with varying ratios of the two compounds. When tested individually, the compounds were minimally attractive. In contrast, adult P. testaceus exhibited nonspecific attraction to both of the individual compounds and to different blends, despite the hydroxyketone not being part of its pheromone, which consists of (R)-2-methyl-1-butanol alone. Overall, our results suggest that a blend of 50:100 of racemic 2-methyl-1-butanol and 3-hydroxy-2-hexanone is appropriate for parallel, cost-efficient pheromone-based monitoring of all three species. In particular, these species could serve as useful indicators of how modern forestry practices affect a whole guild of saproxylic insects that require ephemeral deadwood substrates for successful breeding
Tansy aphid data - Hugh D. Loxdale,FLS, 2007
Tansy aphid data - Hugh D. Loxdale,FLS, 200
Tansy aphid collecting sites, Jena - May 2007 (09.12.08)
Tansy aphid collecting sites, Jena - May 2007 (09.12.08