The effects of a caffeine containing pre-workout supplement on ß2-adrenergic and MAPK signaling during resistance exercise.

AIM: The acute myocellular responses of caffeine supplementation during resistance exercise (RE) have not been investigated. ß2-Adrenergic receptors (ß2AR) may be a target of the stimulatory effects of caffeine and stimulate bioenergetic pathways including protein kinase A (PKA), and mitogen-activated protein kinases (MAPK). PURPOSE: Elucidate the effects of pre-workout supplementation on signaling responses to an acute RE bout. METHODS: In a randomized, counter-balanced, double-blind, placebo-controlled, within-subject crossover study, ten resistance-trained males (mean ± SD; age = 22 ± 2.4 years, height = 175 ± 7 cm, body mass = 84.1 ± 11.8 kg) consumed a caffeine containing multi-ingredient pre-workout supplement (SUPP) or color and flavor matched placebo (PL) 60 min prior to an acute RE bout of barbell back squats. Pre- and post-exercise muscle biopsies were analyzed for the phosphorylation (p-) of ß2AR, PKA, and MAPK (ERK, JNK, p38). Epinephrine was determined prior to supplementation (baseline; BL), after supplementation but prior to RE (PRE), and immediately after RE (POST). RESULTS: Epinephrine increased at PRE in SUPP (mean ± SE: 323 ± 34 vs 457 ± 68 pmol/l; p = 0.028), and was greatest at POST in the SUPP condition compared to PL (5140 ± 852 vs 2862 ± 498 pmol/l; p = 0.006). p-ß2AR and p-MAPK increased post-exercise (p < 0.05) with no differences between conditions (p > 0.05). Pearson correlations indicated there was a relationship between epinephrine and p-ß2AR in PL (r = - 0.810; p = 0.008), and p-ß2AR and ERK in SUPP (r = 0.941; p < 0.001). CONCLUSION: Consumption of a caffeine containing pre-workout supplement improves performance, possibly through increases in pre-exercise catecholamines. However, the acute myocellular signaling responses were largely similar post-exercise.

Dandelion root extracts abolish MAPK pathways to ameliorate experimental mouse ulcerative colitis.

BACKGROUND: Dextran sodium sulfate (DSS)-triggered ulcerative colitis (UC) model in animals provides a valuable platform to preclinically evaluate the outcome of drug candidates for UC. Dandelion root extracts (DRE) have a therapeutic effect on UC. However, the protective mechanism of DRE against UC remains unknown. OBJECTIVES: To discover the targeting pathway involved in DRE-induced protection against UC. MATERIAL AND METHODS: The UC model was developed in C57BL/6 mice by oral administration of DSS. Following DSS exposure, sulfasalazine (SASP), low dose of DRE (DRE-L), moderate dose of DRE (DRE-M), high dose of DRE (DRE-H), and DRE-H plus mitogen-activated protein kinases (MAPK) agonist (DRE-H+MA) were administered to the mice. Colon Mucosal Damage Index (CMDI) and histopathological analysis were used to evaluate the colonic mucosal damage. The cytokine levels were detected using commercial enzyme-linked immunosorbent assay (ELISA) kits. The MAPK pathway activation was determined with western blotting. RESULTS: We found that DRE-H attenuated DSS-triggered colonic mucosal damage. The DSS-induced inflammatory responses and oxidative stress in the bloodstream and colon tissues were dramatically inhibited by DRE-H administration. Also, this plant impaired DSS-provoked phosphorylation levels of extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinases (JNK), p38 mitogen-activated protein kinases (p38), p65, and IκB. More importantly, MAPK agonist, BIM-23A760, removed the protective effect of DRE-H on the bloodstream and colon tissues. CONCLUSIONS: The DRE-H is capable of relieving DSS-induced UC, and its mechanism links to the MAPK pathways.

ACT001 inhibits pituitary tumor growth by inducing autophagic cell death via MEK4/MAPK pathway.

ACT001, derived from traditional herbal medicine, is a novel compound with effective anticancer activity in clinical trials. However, little is known regarding its role in pituitary adenomas. Here, we demonstrated that ACT001 suppressed cell proliferation and induced cell death of pituitary tumor cells in vitro and in vivo. ACT001 was also effective in suppressing the growth of different subtypes of human pituitary adenomas. The cytotoxic mechanism ACT001 employed was mainly related to autophagic cell death (ACD), indicated by autophagosome formation and LC3-II accumulation. In addition, ACT001-mediated inhibitory effect decreased when either ATG7 was downregulated or cells were cotreated with autophagy inhibitor 3-methyladenine (3-MA). RNA-seq analysis showed that mitogen-activated protein kinase (MAPK) pathway was a putative target of ACT001. Specifically, ACT001 treatment promoted the phosphorylation of JNK and P38 by binding to mitogen-activated protein kinase kinase 4 (MEK4). Our study indicated that ACT001-induced ACD of pituitary tumor cells via activating JNK and P38 phosphorylation by binding with MEK4, and it might be a novel and effective anticancer drug for pituitary adenomas.

Hepatoprotective effect of Sophora moorcroftiana (Benth.) Benth.Ex baker seeds in vivo and in vitro.

The leguminosae of Sophora moorcroftiana (Benth.) Benth.ex Baker is a drought-resistant endemic Sophora shrub species from the Qinghai-Tibet Plateau, and its seeds have hepatoprotective effects. To study the effect of S. moorcroftiana seeds on liver injury and the molecular mechanism underlying the beneficial effects, liquid chromatography-mass spectrometry was used to detect the main active components in the ethanol extract of S. moorcroftiana seeds (SM). Male mice were divided into six groups (n = 8): normal control (NC), CCl4, SM (50, 100, 200 mg/kg), and dimethyl diphenyl bicarboxylate (150 mg/kg) groups. Mice were treated as indicated (once/day, orally) for 14 days, and CCl4 (2 mL/kg) was administered intraperitoneally. The serum and liver of mice were used for biochemical assays. To explore the underlying mechanism, HepG2 cells were treated with SM, stimulated with tert-butyl hydroperoxide (t-BHP, 50 µM), and analyzed by Western blotting. The major active compounds of SM were alkaloids including 22 compounds. Serum alanine transaminase (ALT), aspartate transaminase (AST), and alkaline phosphatase (ALP) decreased in the SM (200 mg/kg) group. SM can activate the expression of pregnane X receptor (PXR) and downstream molecules cytochrome P4503A11 enzyme (CYP3A11), UDP glucuronosyltransferase 1 family polypeptide A 1 (UGT1A1), and inhibit the multidrug resistance protein 2 (MRP2). In addition, SM improved cell viability in t-BHP-induced HepG2 cells (64% to 83%) and decreased the activation of the mitogen-activated protein kinase (MAPK) pathway. The main compounds in SM were alkaloids. SM showed hepatoprotective effects possibly mediated by the suppression of oxidative stress through the MAPK pathway.

Eupatilin, a major flavonoid of Artemisia, attenuates aortic smooth muscle cell proliferation and migration by inhibiting PI3K, MKK3/6, and MKK4 activities.

Eupatilin, a major flavonoid of plants in the genus Artemisia, has been shown to exhibit anti-inflammatory, anti-oxidative, and anti-tumor effects. However, the potential anti-atherogenic effects of eupatilin and any underlying mechanisms have not been investigated. In the present study, we sought to determine the effects of eupatilin on phenotypes induced by the growth factor PDGF-BB in human aortic smooth muscle cells. Here we show that aortic sprouting as well as PDGF-BB-induced proliferation and migration of human aortic smooth muscle cells were significantly inhibited by eupatilin. We found that eupatilin inhibited PI3K activity, causing a direct effect on phosphorylation of the downstream kinases Akt and p70S6K. In parallel, eupatilin also inhibited the phosphorylation of MKK3/6-p38 MAPK and the MKK4-JNK pathway. Moreover we found that eupatilin exhibited stronger inhibition effects on PDGF-BB-induced proliferation and migration of human aortic smooth muscle cells than PI3K, p38 MAPK, and JNK pathway inhibitors. Taken together, our results indicate that eupatilin is a potent anti-atherogenic agent that inhibits PDGF-BB-induced proliferation and migration in HASMCs as well as aortic sprouting, which is likely mediated through the attenuation of PI3K, MKK3/6, and MKK4 activation.