ABSTRACT
Betulinic acid (BA) exerts protective effects on organs in septic animals. However, whether BA can improve cardiac function in sepsis and the underlying mechanism remain unclear. Here, male Sprague-Dawley rats were pretreated with BA (25 mg/ kg/ d, i. g.) for 5 days and then intraperitoneally injected with lipopolysaccharide (LPS, 10 mg/ kg). The rats were anesthetized to determine transthoracic echocardiography using a high-resolution imaging system for small animals after they were treated with LPS for 6 h. Histopathologic alterations were examined by HE staining. Myocardial injury markers (cTnI and CK-MB) and inflammatory factors (TNF-α, IL-1β and IL-6) in the serum were measured by the enzyme-linked immunosorbent assay. Autophagy-related proteins (p62 and LC3 Ⅱ) and AKT-modulated autophagy pathways in the myocardium were determined by Western blotting. Pretreatment with BA markedly improved left ventricular ejection fraction (EF) and fraction shortening (FS) (P<0. 05), improved myocardial histomorphology, and significantly inhibited cTnI, CK-MB, TNF-α, IL-1β and IL-6 (P<0. 05) in the septic rat serum. BA markedly decreased p62 (P<0. 01), increased LC3 Ⅱ (P< 0. 001), and significantly down-regulated p-AKT (Thr308), p-AMPKα (Ser485/ 491), p-mTOR (Ser2448) and p-S6K (Thr389) (P<0. 05), while markedly up-regulated p-AMPKα (Thr172) and pULK1 (Ser317) (P<0. 01) in septic rat hearts. The findings indicate that BA can attenuate sepsis-induced myocardial dysfunctions associated with down-regulating autophagy inhibiting pathways mediated by AKT/ mTOR and AKT/ AMPK pathways.
ABSTRACT
Water lily is an important ornamental flower plant which is capable of viviparous plantlet development. But no study has been reported on the molecular basis of viviparity in water lily. Hence, we performed a comparative transcriptome study between viviparous water lily Nymphaea micrantha and a nonviviparous species Nymphaea colorata at four developmental stages. The higher expression of highly conserved AUX/IAA, ARF, GH3, and SAUR gene families in N. micrantha compared to N. colorata is predicted to have a major impact on the development and evolution of viviparity in water lily. Likewise, differential regulation of hormone signaling, brassinosteroid, photosynthesis, and energy-related pathways in the two species provide clues of their involvement in viviparity phenomenon. This study revealed the complex mechanism of viviparity trait in water lily. The transcriptomic signatures identified are important basis for future breeding and research of viviparity in water lily and other plant species.
