RESUMEN
AIM To explore the protective effect and mechanism of dihydromyricetin (DHM) on atherosclerosis (AS) in ApoE-/-mice induced by high fat diet (HFD).METHODS Thirty healthy 6-week-old male ApoE-/-mice were randomly divided into model group,DHM group [50 mg/(kg · d)] and Atorvastatin group [5 mg/(kg · d),i.g.],and another 10 male C57BL/6J mice were taken for control group.The mice in the control and model group were administered with 0.5％ CMC-Na solution,while the other two groups were given DHM and atorvastatin suspension (0.2 mL/10 g).All mice went on with a 10-week HFD diet (0.3％ cholesterol,20％ fat),after which the orbit blood was procured for serum isolation and subsequent determination of levels of SOD,GSH-Px,CAT and MDA by the biochemical analyzer and test of lipid accumulation in the aotic root by oil red O.The detection of macrophages accumulation and Caspase-3 expression level in the aortic root were achieved by immunofluorescence,and the macrophages apoptosis by TUNEL assay.RESULTS Significant post-treatment reduction in levels of TG,TC,and remarkable amelioration of LDL-C and plaque area in the aortic root were observed in DHM group when compared with model group.Meanwhile,DHM contributed to marked decrease of MDA level and improvement in activities of CAT,GSH-Px and SOD,the obvious macrophages accumulation prevention in atherosclerotic plaque.Additionally,its significant inhibition on macrophage apoptosis in aortic root was verified by the TUNEL assay.CONCLUSION DHM reduces the lipid accumulation in HFD-induced ApoE-/-mice,mechanically a resultant of its inhibition on macrophage apoptosis.
RESUMEN
The focus of this study is to investigate if microcrustaceans undergo diel horizontal migration (DHM) in a tropical shallow lake on a yearly basis and analyse the adaptive value regarding predation. Abundance of invertebrate predators, chaoborid larvae and water mites, and microcrustaceans (cladocerans and copepods) were evaluated on a monthly basis in three stations located on a transect during the day and at night. Both invertebrate predators were predominantly pelagic. Cladocerans did not undergo significant DHM, distributing indistinctly onshore and offshore or being mostly pelagic. Nauplii, copepodites of two copepod species and adults of Tropocyclops prasinus meridionalis Kiefer were mostly distributed offshore, and did not perform DHM. The limnological features (temperature, dissolved oxygen, pH, and conductivity) were suitable for the organisms in both zones of the lake. Algal food concentration was a little lower in the littoral than in the limnetic zone during the day, but it seems to be suitable for the organisms. However, as the algae quality was not evaluated, it is not possible to be conclusive concerning its influence. The results indicated that DHM was not performed by the microcrustaceans and is not, therefore, a strategy for decreasing predation by both invertebrates, Chaoborus brasiliensis Theobald and Krendowskia sp., on a yearly basis in this shallow lake.
O foco deste estudo é verificar se microcrustáceos apresentam migração horizontal diária (MHD) em um lago raso tropical, durante um ano, e o valor adaptativo com relação à predação. A abundância de predadores invertebrados, larvas de caoborídeos e ácaros aquáticos, e de cladóceros e copépodos foi avaliada mensalmente em três estações de coleta localizadas em um transecto, de dia e à noite. Ambos os predadores invertebrados foram predominantemente pelágicos. Os cladóceros não realizaram MHD, distribuindo-se indistintamente nas zonas litorânea e pelágica, ou foram mais abundantes na zona limnética. Os náuplios e copepoditos de duas espécies de copépodos e os adultos de Tropocyclops prasinus meridionalis Kiefer ocuparam principalmente a zona limnética, não migrando horizontalmente. As características limnológicas (temperatura, oxigênio dissolvido, pH e condutividade) foram adequadas nas duas zonas do lago. A concentração de alga foi um pouco menor no litoral do que na zona limnética durante o dia e parece ser adequada para os organismos; contudo, como a qualidade das algas não foi avaliada, não é possível ser conclusivo sobre sua influência. Os resultados indicaram que os microcrustáceos não realizaram MHD, a qual não constitui, portanto, uma estratégia para diminuir a predação dos dois invertebrados, Chaoborus brasiliensis Theobald e Krendowskia sp., em uma base anual, neste lago raso.