Pinoresinol diglucoside ameliorates H/R-induced injury of cardiomyocytes by regulating miR-142-3p and HIF1AN

This study is aimed to investigate the effect of pinoresinol diglucoside (PDG) in ameliorating myocardial ischemia-reperfusion injury (MIRI). Hypoxia/reperfusion (H/R)-induced H9c2 cardiomyocytes were used to establish an in-vitro ischemia-reperfusion injury model of cardiomyocytes. Cells were treated with 1 μmol/L of PDG. Reactive oxygen species (ROS) level was detected by a 2',7'-dichlorofluorescein-diacetate assay. The release of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) was examined by enzyme-linked immunosorbent assay. The viability and apoptosis of H9c2 cells were probed by MTT assay and flow cytometry. Besides this, Western blot and quantitative real-time PCR were used to detect microRNA-142-3p (miR-142-3p) and hypoxia-inducible factor 1 subunit alpha inhibitor (HIF1AN) expression levels. The binding sequence between miR-142-3p and HIF1AN 3'-untranslated region was validated by a dual-luciferase reporter gene assay. PDG treatment significantly reduced the level of ROS, LDH, and CK-MB, promoted viability, and inhibited the apoptosis of H9c2 cells. PDG treatment promoted miR-142-3p expression and inhibited HIF1AN expression in H9c2 cells. MiR-142-3p overexpression enhanced the effects of PDG on ROS, LDH, CK-MB levels, cell viability, and apoptosis in H9c2 cardiomyocytes, while overexpression of HIF1AN reversed the above effects. PDG ameliorates H/R-induced injury of cardiomyocytes by regulating miR-142-3p and HIF1AN.

Pinoresinol diglucoside alleviates ischemia/reperfusion-induced brain injury by modulating neuroinflammation and oxidative stress

Brain ischemia/reperfusion (I/R) injury is a common pathological process after ischemic stroke. Pinoresinol diglucoside (PDG) has antioxidation and anti-inflammation activities. However, whether PDG ameliorates brain I/R injury is still unclear. In this study, middle cerebral artery occlusion (MCAO) model was established with male C57BL/6 mice, and the mice were treated with 5 and 10 mg/kg PDG via intravenous injection, respectively. The neurological deficit, infarct volume, and brain water content were then evaluated. HE staining and Nissl staining were used to analyze neuron injury. Besides, enzyme-linked immunosorbent assay and colorimetry assay were used to examine the level of inflammatory markers and oxidative stress markers, and Western blot was used to detect the expressions of p-p65, Nrf2, and HO-1. It was revealed that PDG could significantly alleviate the MCAO-induced neurological dysfunction of the mice and reduce the infarct volume, brain water content, and neuron injury. PDG treatment decreased the levels of TNF-α, IL-1β, IL-6, NO, ROS, and MDA, and significantly increased the activities of SOD, GSH, and GSH-Px in the brain tissue of the mice. Additionally, PDG could repress the activation of p65 and promote Nrf2 and HO-1 expressions. In conclusion, PDG exerts anti-inflammatory and antioxidation effects via regulating the NF-κB pathway and Nrf2/HO-1 pathway, thereby reducing the I/R-induced brain injury of mice.

Comparison of Pinoresinol and its Diglucoside on their ADME Properties and Vasorelaxant Effects on Phenylephrine-Induced Model

Pinoresinol (PINL) and pinoresinol diglucoside (PDG), two natural lignans found in Eucommia ulmoides Oliv. (Duzhong), have several pharmacological activities. However, there is no report available on their absorption, distribution, metabolism, and elimination (ADME) properties. Given the possible wide spectrum of their application in therapeutic areas, this area should be investigated. This work studied the in vitro ADME properties of PDG and PINL, including their kinetic solubility, permeability across monolayer cells (PAMPA), protein binding, and metabolic stabilities in liver microsomes. The in vivo pharmacokinetic study and in vitro vasorelaxant effects on isolated phenylephrine-induced aortic rings of PINL and PDG were also investigated. It was found that both of their kinetic solubility in PBS (pH 7.4) was greater than 100 μM, indicating that they are both soluble compounds. The permeability investigations (P_eff) by PAMPA indicated that PINL had higher permeability than PDG (p < 0.05). Both components represented moderate plasma protein binding activities (average binding rate in human plasma: PINL 89.03%, PDG 45.21%) and low metabolic rate (t_1/2 in human liver microsome: PINL 1509.5 min, PDG 1004.8 min). Furthermore, the results of pharmacokinetic studies indicated that PINL might be eliminated less quickly than PDG from the rat plasma, and its cumulative urinary excretion was much lower than that of PDG. The phenylephrine-induced aortic rings demonstrated concentration-dependent vasorelaxation in PDG, PINL, or their combination group. The vasorelaxant effects of PINL were more obvious than those of PDG, whereas the vasorelaxant effect of the combinations was significantly better than that of the single component (p < 0.05). The similarity or difference between PINL and its diglucoside in these pharmaceutical aspects may offer valuable insights into the further exploration of lignans and might contribute to relevant studies involving natural products with similar molecular structure and their glucosides.

XP-8 in different media and the characterisation and product profiles of the cultivation in mung bean

BACKGROUND

Phomopsis sp. XP-8 is an endophytic fungus with the ability to produce pinoresinol diglucoside (PDG) in vitro and thus has potential application in biosynthesis of PDG independent of plants. In order to enhance the production of PDG, 18 different natural materials were tested in solid-state cultivation of Phomopsis sp. XP-8.

RESULTS

Most of the tested natural materials promoted the production of PDG. A supplement derived from mung beans produced the highest PDG yield and better fungal growth than the other materials. Also, pinoresinol monoglucoside, pinoresinol and other substrates (phenylalanine, p-coumaric acid, cinnamic acid, caffeic acid, and ferulic acid) were obtained after fermentation on mung beans. Furthermore, PDG production was much higher when mung beans were incorporated into solid state agar versus a liquid medium. The highest pinoresinol diglucoside production (72.1 mg kg(-1) in fresh culture) was obtained in 9 days using a solid state culture of Phomopsis sp. XP-8 on a mung bean grain medium containing 100 g kg(-1) glucose. Mung bean water-soluble polysaccharide was identified as a major promoter of PDG production by Phomopsis sp. XP-8.

CONCLUSION

Mung bean, especially its water-soluble polysaccharide fraction, was an efficient natural material to promote PDG production by Phomopsis sp. XP-8. © 2015 Society of Chemical Industry.