The p38 MAPK Inhibitor SB203580 Blocks Adenosine A1 Receptor-Induced Attenuation of In Vivo Myocardial Stunning

Background Local anesthetic-induced direct neurotoxicity (paresthesia, failure to regain normal sensory and motor function) is a potentially devastating complication of regional anesthesia. Local anesthetics activate the p38 mitogen-activated protein kinase (MAPK) system, which is involved in apoptotic cell death. The authors therefore investigated in vitro (cultured primary sensory neurons) and in vivo (sciatic nerve block model) the potential neuroprotective effect of the p38 MAPK inhibitor SB203580 administered together with a clinical (lidocaine) or investigational (amitriptyline) local anesthetic. Methods Cell survival and mitochondrial depolarization as marker of apoptotic cell death was assessed in rat dorsal root ganglia incubated with lidocaine or amitriptyline either with or without the addition of SB203580. Similarly, in a sciatic nerve block model, the authors assessed wallerian degeneration by light microscopy to detect a potential mitigating effect of MAPK inhibition. Results Lidocaine at 40 mm/approximately 1% and amitriptyline at 100 microm reduce neuron count, but coincubation with the p38 MAPK inhibitor SB203580 at 10 mum significantly reduces cytotoxicity and the number of neurons exhibiting mitochondrial depolarization. Also, wallerian degeneration and demyelination induced by lidocaine (600 mm/approximately 15%) and amitriptyline (10 mm/approximately 0.3%) seem to be mitigated by SB203580. Conclusions The cytotoxic effect of lidocaine and amitriptyline in cultured dorsal root ganglia cells and the nerve degeneration in the rat sciatic nerve model seem, at least in part, to be mediated by apoptosis but seem efficiently blocked by an inhibitor of p38 MAPK, making it conceivable that coinjection might be useful in preventing local anesthetic-induced neurotoxicity.

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Cordycepin Modulate Body Weight by Reducing Prolactin via an Adenosine A1 Receptor

10.20944/preprints201804.0033.v1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Yuan Li ◽

Yan Li ◽

Xueyan Wang ◽

Hongyue Xu ◽

Chao Wang ◽

...

Keyword(s):

Body Weight ◽

Prolactin Secretion ◽

Adenosine A1 Receptor ◽

Gh3 Cells ◽

Serum Prolactin ◽

Prolactin Release ◽

Adenosine A1 ◽

A1 Receptor

Cordycepin is an extract from the insect fungus Cordyceps. militaris, which is a traditional medicine with various biological function. In previous studies, cordycepin had been reported with excellent anti-obesity effect, but the mechanism is unclear. A large quantity of evidences showed that prolactin plays an important part in body weight regulation, hyperprolactinemia can promote appetite and accelerate fat deposition. In this study, we explored the molecular mechanism of the anti-obesity effect of cordycepin by reducing prolactin release via an adenosine A1 receptor. In vivo, obese rats model was induced by high fat diet for 5 weeks, the serum and liver lipids coupling with serum prolactin were reduced by treatment of cordycepin, the results suggested that cordycepin is a potential drug for therapying obesity which could be related with prolactin. In vitro, cordycepin could inhibit prolactin secretion in GH3 cells via upregulating the expression of adenosine A1 receptor, the inhibition effect could be blocked by an antagonist of adenosine receptor A1 DPDPX, prolactin induced the upregulation of lipogenesis genes PRLR, and P-JAK2 in 3T3-L1 cells. Intriguingly, cordycepin would down-regulate the expression of prolactin receptor (PRLR). Thus, we concluded that cordycepin modulate body weight by reducing prolactin release via an adenosine A1 receptor.

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Cordycepin Modulates Body Weight by Reducing Prolactin Via an Adenosine A1 Receptor

Current Pharmaceutical Design ◽

10.2174/1381612824666180820144917 ◽

2018 ◽

Vol 24 (27) ◽

pp. 3240-3249 ◽

Cited By ~ 4

Author(s):

Yuan Li ◽

Yan Li ◽

Xueyan Wang ◽

Hongyue Xu ◽

Chao Wang ◽

...

Keyword(s):

Body Weight ◽

Liver Lipid ◽

Adenosine A1 Receptor ◽

Gh3 Cells ◽

Serum Prolactin ◽

Lipid Levels ◽

Adenosine A1 ◽

A1 Receptor

Background: Cordycepin is an extract from the insect fungus Cordyceps. militaris with various biological function. In previous studies, cordycepin has demonstrated an excellent anti-obesity effect, but the mechanism is unclear. It was also demonstrated that prolactin played an important role in body weight regulation and hyperprolactinemia can promote appetite and accelerate fat deposition. In this study, we explored the molecular mechanism of the anti-obesity effect of cordycepin. Methods: In Vivo, the obese rat model was induced by high fat diet for five weeks, and the serum and liver lipid levels coupled with the serum prolactin levels were reduced following cordycepin treatment (P<0.01). Results: The results suggested that cordycepin is a potential drug that lowers blood and liver lipid levels and reduces body weight related to prolactin. Cordycepin also protects adipocytes from enlargement and hepatocytes from lipotoxicity-induced inflammation. In vitro, cordycepin inhibited prolactin secretion in GH3 cells via upregulating the expression of adenosine A1 receptor, and the inhibition effect was blocked by an antagonist of adenosine receptor A1 DPDPX, demonstrating that cordycepin may work as an adenosine agonist. Additionally, cordycepin inhibited the ERK/AKT/PI3K pathway in GH3 cells. At the same time, cordycepin blocked prolactininduced upregulation of lipogenesis genes PRLR, and phosphorylation of JAK2 in 3T3-L1 cells. In an in vivo study, cordycepin downregulated the expression of prolactin receptor (PRLR) but not the phosphorylation of JAK2. Conclusion: Thus, it was proved that cordycepin modulates body weight by reducing prolactin release via an adenosine A1 receptor.

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