Nobiletin represses change in the levels of blood coagulation markers in the LPS-induced rat DIC model
FUNCTIONAL FOODS IN HEALTH AND DISEASE
Authors: Takada, Kimihiko; Takano, Mayuko; Kunii, Aiko; Harayama, Kei; Miyazaki, Yoshiko; Masuda, Yutaka
Abstract
Background: Nobiletin is contained in Shiikuwasa fruit, a popular citrus fruit from Okinawa Prefecture in Japan. Nobiletin reportedly acts as a strong antioxidant, an anti-inflammatory agent, and an anti-cancer agent, and it suppresses the expression of TF which triggers blood coagulation. However, in vivo verification of in vitro reports is necessary. This study used a rat model of LPSinduced microthrombosis based on the in vivo studies as previously reported. Sustained intravenous injection of LPS changed all blood coagulation indicators in the direction of thrombus formation. The aim of this study was to determine if intake of nobiletin could suppress DIC-like symptoms. Methods: Experimental SD rats were fully anesthetized and fixed to an operating table. Either LPS alone or nobiletin (50 mg/kg) plus LPS was given to rats to investigate the repressive effects of nobiletin on the expression of blood coagulation factors. Results: After 4 h of LPS infusion (12.5 mg/kg/h, i.v.), PLT counts and Fbg levels in rat plasma decreased by 80% and 74%, respectively. PT and APTT were extended by 180% and 256%, respectively. TF activity and PAI-1 antigen levels were remarkably increased (54- and 86-fold, respectively vs. control). Pretreatment on nobiletin (50 mg/kg, p.o.) reduced or suppressed fluctuations in blood coagulation indices caused by LPS. TF activity was repressed almost completely by nobiletin pretreatment. After 4 h, PAI-1 antigen levels in nobiletin-treated animals were repressed 82.6% compared to LPS-treated rats. Nobiletin repressed LPS-induced changes in TF and PAI-1 more effectively than other parameters. Further, nobiletin repressed fibrin thrombi formation in the renal glomeruli induced by LPS treatment. Conclusions: Nobiletin was found to reduce LPS-induced DIC-like symptoms in rats. In the fluctuations of blood indices related to the coagulation cascade, nobiletin suppressed the LPS-induced expression of PAI-1 and TF more effectively than other indices. The binding sites of transcription factors that are activated by LPS-induced signals reside in the promoter areas of TF and PAI-1 gene sequences. Thus, the suppression of TF and PAI-1 expression by nobiletin appears similar to mechanisms previously evaluated during in vitro experiments. Importantly, nobiletin repressed fibrin deposition in the renal glomeruli induced by LPS treatment and improved overall health. Nobiletin may function as an anti-thrombogenic agent when ingested daily.
Distributed transverse-force sensing along a single-mode fiber using polarization-analyzing OFDR
OPTICS EXPRESS
Authors: Feng, Ting; Zhou, Junnan; Shang, Yanling; Chen, Xiaojun; Yao, X. Steve
Abstract
We report what we believe to be the first demonstration of a direct distributed transverse-force (TF) sensing along a single-mode fiber (SMF) using a self-built polarization-analyzing optical frequency-domain reflectometry (PA-OFDR). The transverse line-force (TLF) distribution along a SMF can be directly obtained from the absolute measurement of birefringence induced by the TF via photo-elastic effect at different locations along the fiber, without the need of complicated force-to-strain conversion. We show that our system is capable of sensing a weight of merely 0.68 g but yet has a large dynamic range of over 44 dB. In particular, we obtained a maximum detectable TLF of 16.8 N/mm, a minimum detectable TLF of 6.61 x10(-4) N/mm, a TLF measurement uncertainty of <2.432%, a TF sensing spatial resolution of 3.7 mm and a TF sensing distance of 103.5 m. We also experimentally investigated the influence of different fiber coatings on the TF sensing and found that the polyimide coating is a better choice due to its high TF measurement sensitivity and response speed, although it induces relatively high residual birefringence in the SMF to limit the minimum detectable TLF. Our work is an important step forward for practical distributed TF sensing and shall prove useful for engineers and scientists to implement the PA-OFDR technology for distributed TF sensing with low cost SMFs. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement