Effects of long-term intake of Antarctic krill oils on artery blood pressure in spontaneously hypertensive rats.

BACKGROUND: In recent years, there has been a noticeable increase in research on krill oil (KO) for its health benefits. However, the action of KO in lowering blood pressure (BP) has not been studied yet. Therefore the aim of this study was to assess the ability of long-term KO supplementation to lower systolic BP (SBP) in spontaneously hypertensive rats (SHRs) and Sprague Dawley (SD) rats. RESULTS: Compared with the blank control (BC) SHRs administered edible soybean oil, the high-dose (500 mg kg-1 body weight (BW)) KO-supplemented SHRs in the 2nd, 3rd, 4th and 5th weeks following oral administration, the mid-dose (100 mg kg-1 BW) KO-supplemented SHRs in the 4th and 5th weeks following oral administration and the low-dose (20 mg kg-1 BW) KO-supplemented SHRs in the 5th week following oral administration showed significantly lower SBP (P < 0.05). However, supplementation of KO had no significant effect on the SBP of healthy SD rats. Meanwhile, 5 weeks of KO administration significantly increased the serum levels of nitric oxide (NO) and total NO synthase of SHRs (P < 0.05). CONCLUSION: KO has an antihypertensive effect in SHRs that is associated with an NO-related mechanism. © 2016 Society of Chemical Industry.

Strength evaluation of transcriptional regulatory elements for transgene expression by adenovirus vector.

In studies of both gene function and gene therapy, transgene expression may be assisted considerably through the use of transcriptional regulatory elements with high activity. In this study, we evaluated the strength of various transcriptional regulatory elements both in vitro (six types of cell line) and in vivo (mouse heart, lung, kidney, spleen, and liver) by adenovirus-mediated gene transfer. In the case of the promoter/enhancer (P/E), the activity of CMV P/E (from the human cytomegalovirus immediate-early 1 gene) and hybrid CA P/E (composed of the CMV enhancer and chicken beta-actin promoter) were investigated, both of which are known to be strong and widely used. While hybrid CA P/E showed a higher transgene expression activity than CMV P/E, the addition of the intron A sequence (the largest intron of CMV) to CMV P/E increased the activity of CMV P/E to the same or higher level than that of hybrid CA P/E. Concerning the polyadenylation signal (P(A)) sequence, one from the bovine growth hormone (BGH) gene was about two times more efficient than that from the Simian virus 40 (SV40) late gene, both in vitro and in vivo. In the context of the CMV P/E containing the intron A sequence, a further increase in transgene expression was obtained by the addition of a SV40 enhancer downstream from the P(A) sequence. The combination of the SV40 P(A) and a SV40 enhancer showed almost comparable activity to BGH P(A). This information would be helpful for the construction of adenovirus vectors for studies regarding both gene function and gene therapy.