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The incidence of cardiovascular diseases, such as high blood pressure, is increasing worldwide, owing to population aging and irregular lifestyle habits. Previous studies have reported the vasorelaxant effects of Prunus yedoensis bark methanol extract. However, various solvent extracts of P. yedoensis bark and their vascular relaxation mechanisms have not been sufficiently studied. We prepared extracts of P. yedoensis bark using various solvents (water, 30% ethanol, and 70% ethanol). P. yedoensis bark 30% ethanol extract (PYB-30E) decreased the expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin in human umbilical vein endothelial cells (HUVECs) activated with 200 ng/mL TNF-α. Additionally, PYB-30E showed vasodilatory effects on isolated rat aortic rings. This was confirmed to be the result of the activation of the NO/cGMP pathway, regulation of non-selective calcium-activated K+ channels, and calcium channel blockade. Additionally, PYB-30E significantly reduced systolic and diastolic blood pressure in spontaneously hypertensive rats (SHR). Taken together, our results indicated that PYB-30E is a candidate functional material with preventive and therapeutic effects against hypertension.

Hypertension is the crucial modifiable risk factor for cardiovascular diseases, and efforts to identify functional foods that are effective for hypertension control are increasing. The nutgall tree (NT, Rhus chinensis Mill.) is used in traditional medicine and food because of its medicinal value. However, the role of NT in hypertension has not been investigated. Therefore, the hypotensive effect of NT leaf ethanol extract (NTE) was investigated in spontaneously hypertensive rats (SHRs). SHRs were allocated to three groups (control, 300, or 1000 mg/kg NTE), and blood pressure was measured before and after oral administration. Systolic and diastolic blood pressure significantly decreased in the NTE 1000 mg/kg group and was the lowest at 2 h after administration (−26.4 ± 10.3, −33.5 ± 9.8%, respectively). Daily NTE administration for five days also resulted in a similar effect. Further, the vasorelaxant effects and related mechanisms were investigated in the aortas of Sprague Dawley rats. NTE showed the dose-dependent blood-vessel-relaxing effect, and its mechanism involves the NO-sGC-cGMP pathway, activation of K+ channels, and reduction in the vasoconstrictive action of angiotensin II. Therefore, our study provides basic data indicating the potential use of NTE as a functional food for high blood pressure.

Natural compounds, known for diverse pharmacological properties, have attracted attention as potential sources for hypertension treatment. Previous studies have revealed the hypotensive effect and vascular relaxation of prunetin, a natural compound derived from Prunus yedoensis. However, the potential blood pressure-lowering and vasorelaxant effects of sakuranetin, another representative compound found in plants belonging to the genus Prunus, have remained unexplored. We aimed to fill this gap by investigating the hypotensive and vasorelaxant effects of sakuranetin in rats. Results indicated that sakuranetin, particularly in the sakuranetin 20 mg/kg group, led to significant reductions in systolic blood pressure (SBP) and diastolic blood pressure (DBP) by −14.53 ± 5.64% and −19.83 ± 6.56% at 4 h after administration. In the sakuranetin 50 mg/kg group, the SBP and DBP decreased by −13.27 ± 6.86% and −16.62 ± 10.01% at 2 h and by −21.61 ± 4.49% and −30.45 ± 5.21% at 4 h after administration. In addition, we identified the vasorelaxant effects of sakuranetin, attributing its mechanisms to the inhibition of calcium influx and the modulation of angiotensin II. Considering its hypotensive and vasorelaxant effects, sakuranetin could potentially serve as an antihypertensive agent. However, further research is required to evaluate the safety and long-term efficacy.

Hypertension is one of the most common chronic diseases, and its prevalence is increasing worldwide. Lindera glauca (Siebold & Zucc.) Blume, known as grayblue spicebush (GS), has been used as food and for medicinal purposes; however, studies about its hypotensive or vasorelaxant effects are lacking. Therefore, the hypotensive effect of an ethanolic extract of the GS branch (GSE) was investigated in 15-week-old spontaneously hypertensive rats (SHRs) using the tail cuff method. The GSE administration group (1000 mg/kg SHR body weight) showed a decrease in their systolic and diastolic blood pressure measured 4 h after its administration. In addition, we investigated its vasorelaxant effect using the thoracic aorta dissected from Sprague-Dawley rats. The GSE (0.5, 1, 2, 5, 10, and 20 μg/mL) showed an endothelium-dependent vasorelaxant effect, and its mechanisms were found to be relevant to the inward rectifier, voltage-dependent, and non-selective K+ channels. Moreover, the GSE (20 μg/mL) showed an inhibitory effect on aortic rings constricted with angiotensin II. Considering its hypotensive and vasorelaxant effects, GSE has potential as a functional food to help treat and prevent high blood pressure. However, further studies on the identification of the active components of GSE and safety evaluations of its use are needed.

Inotodiol, an oxysterol found only in Chaga mushroom, has received attention from the pharmaceutical industry due to its strong antioxidant and anti-allergic activities. However, the production of inotodiol is still challenging, and its fundamental properties have yet to be investigated. This study aims to develop an efficient method to produce high-purity inotodiol from Chaga mushroom. Then, pure inotodiol was used to assess its physicochemical properties and biological activities. By optimizing the solvent used for extraction and purification, a new method to produce inotodiol was developed with high purity (>97%) and purification yield (33.6%). Inotodiol exhibited a melting point (192.06 °C) much higher than lanosterol and cholesterol. However, the solubility of inotodiol in organic solvents was notably lower than those of the other two sterols. The difference in the hydroxyl group at C-22 of inotodiol has shown the distinctive physicochemical properties of inotodiol compared with cholesterol and lanosterol. Based on those findings, a nonionic surfactant-based delivery system for inotodiol was developed to improve its bioavailability. The inotodiol microemulsion prepared with 1–2% Tween-80 exhibited homogenous droplets with an acceptable diameter (354 to 217 nm) and encapsulation efficiency (85.6–86.9%). The pharmacokinetic analysis of inotodiol microemulsion in oral administration of 4.5 mg/kg exhibited AUC0–24h = 341.81 (ng·h/mL), and Cmax = 88.05 (ng/mL). Notably, when the dose increased from 4.5 to 8.0 mg/kg, the bioavailability of inotodiol decreased from 41.32% to 33.28%. In a mouse model of sepsis, the serum level of interleukin-6 significantly decreased, and the rectal temperature of mice was recovered in the inotodiol emulsion group, indicating that inotodiol microemulsion is an effective oral delivery method. These results could provide valuable information for applying inotodiol in functional food, cosmetic, and pharmaceutical industries.

Detecting objects in synthetic aperture radar (SAR) imagery has received much attention in recent years since SAR can operate in all-weather and day-and-night conditions. Due to the prosperity and development of convolutional neural networks (CNNs), many previous methodologies have been proposed for SAR object detection. In spite of the advance, existing detection networks still have limitations in boosting detection performance because of inherently noisy characteristics in SAR imagery; hence, separate preprocessing step such as denoising (despeckling) is required before utilizing the SAR images for deep learning. However, inappropriate denoising techniques might cause detailed information loss and even proper denoising methods does not always guarantee performance improvement. In this paper, we therefore propose a novel object detection framework that combines unsupervised denoising network into traditional two-stage detection network and leverages a strategy for fusing region proposals extracted from both raw SAR image and synthetically denoised SAR image. Extensive experiments validate the effectiveness of our framework on our own object detection datasets constructed with remote sensing images from TerraSAR-X and COSMO-SkyMed satellites. Extensive experiments validate the effectiveness of our framework on our own object detection datasets constructed with remote sensing images from TerraSAR-X and COSMO-SkyMed satellites. The proposed framework shows better performances when we compared the model with using only noisy SAR images and only denoised SAR images after despeckling under multiple backbone networks.