Ethyl 3,4-dihydroxybenzoate

[Steroids and aromatic derivatives from Euphorbia micractina].[Pubmed:27141676]

Zhongguo Zhong Yao Za Zhi. 2015 Dec;40(23):4639-44.

From an ethanol extract of Euphorbia micractina roots, seven steroids fifteen aromatic derivatives were isolated by a combination of various chromatographic techniques, including column chromatography over macroporous resin, silica gel, and Sephadex LH-20 and reversed-phase HPLC. Their structures were elucidated by spectroscopic data analysis as stigamast-5-ene-3beta, 7alpha-diol(1), stigamast-5-ene-3beta,7beta-diol(2), stigmast-5-en-3beta-ol-7-one(3), stigmast-4-en-6beta-ol-3-one(4), stigmast-1, 4-dien-3-one(5), stigmast-3,6-dione(6), beta-sitosterol(7), scopoletin(8), aesculetin(9), 6-hydroxy-5,7-dimethoxycoumarin(10), quercetin(11), 3,3', 4'-tri-O-methylellagic acid(12), p-hydroxyphenylethyl anisate(13), m-hydroxyphenylethyl alcohol(14), (E)-cinnamic acid(15), (E)-ferulic acid(16), 3,4-dihydroxybenzoic acid(17), vanillic acid(18), p-hydroxybenzoic acid(19), Ethyl 3,4-dihydroxybenzoate (20), ethyl gallate(21), and methyl gallate(22). These compounds were obtained from this plant for the first time.

Preconditioning with ethyl 3,4-dihydroxybenzoate augments aerobic respiration in rat skeletal muscle.[Pubmed:27800513]

Hypoxia (Auckl). 2016 May 13;4:109-120.

Muscle respiratory capacity decides the amount of exertion one's skeletal muscle can undergo, and endurance exercise is believed to increase it. There are also certain preconditioning methods by which muscle respiratory and exercise performance can be enhanced. In this study, preconditioning with Ethyl 3,4-dihydroxybenzoate (EDHB), a prolyl hydroxylase domain enzyme inhibitor, has been investigated to determine its effect on aerobic metabolism and bioenergetics in skeletal muscle, thus facilitating boost in physical performance in a rat model. We observed that EDHB supplementation increases aerobic metabolism via upregulation of HIF-mediated GLUT1 and GLUT4, thus enhancing glucose uptake in muscles. There was also a twofold rise in the activity of enzymes of tricarboxylic acid (TCA) cycle and glycolysis, ie, hexokinase and phosphofructokinase. There was an increase in citrate synthase and succinate dehydrogenase activity, resulting in the rise in the levels of ATP due to enhanced Krebs cycle activity as substantiated by enhanced acetyl-CoA levels in EDHB-treated rats as compared to control group. Increased lactate dehydrogenase activity, reduced expression of monocarboxylate transporter 1, and increase in monocarboxylate transporter 4 suggest transport of lactate from muscle to blood. There was a concomitant decrease in plasma lactate, which might be due to enhanced transport of lactate from blood to the liver. This was further supported by the rise in liver pyruvate levels and liver glycogen levels in EDHB-supplemented rats as compared to control rats. These results suggest that EDHB supplementation leads to improved physical performance due to the escalation of aerobic respiration quotient, ie, enhanced muscle respiratory capacity.

MicroRNA-17-5p mediates hypoxia-induced autophagy and inhibits apoptosis by targeting signal transducer and activator of transcription 3 in vascular smooth muscle cells.[Pubmed:28450922]

Exp Ther Med. 2017 Mar;13(3):935-941.

The aim of the present study was to investigate hypoxia-induced apoptosis and autophagy in vascular smooth muscle cells (VSMCs) and the underlying molecular mechanisms of microRNA (miR)-17-5p responses in an anaerobic environment. The results revealed that miR-17-5p expression was significantly upregulated in VSMCs subjected to hypoxic conditions (P<0.05) and lower miR-17-5p levels were observed in Ethyl 3,4-dihydroxybenzoate-treated and hypoxia inducible factor-1 loss-of-function cells. Additionally, it was demonstrated that miR-17-5p is associated with hypoxia-induced autophagy, which was confirmed by upregulating the light chain 3-II/LC3-I ratio and downregulating nucleoporin p62. Cell apoptosis was inhibited in response to hypoxia, and levels of pro-apoptotic proteins B-cell lymphoma 2-associated X protein and p-caspase were markedly decreased when VSMCs were subjected to hypoxic conditions. Furthermore, expression of signal transducer and activator of transcription 3 (STAT3) decreased when cells were transfected with overexpressing miR-17-5p and subjected to hypoxic conditions, and the combination of miR-17-5p loss-of-function and hypoxia induced greater upregulation in the protein expression of STAT3 compared with a single treatment for hypoxia in VSMCs. In conclusion, miR-17-5p may be a novel hypoxia-responsive miR and hypoxia may induce protective autophagy and anti-apoptosis in VSMCs by targeting STAT3.