Inhibitory effect of the intravenous anesthetic, ketamine, on rat mesangial cell proliferation

Drug Repurposing: The Mechanisms and Signaling Pathways of Anti-Cancer Effects of Anesthetics

Cancer is one of the leading causes of death worldwide. There are only limited treatment strategies that can be applied to treat cancer, including surgical resection, chemotherapy, and radiotherapy, but these have only limited effectiveness. Developing a new drug for cancer therapy is protracted, costly, and inefficient. Recently, drug repurposing has become a rising research field to provide new meaning for an old drug. By searching a drug repurposing database ReDO_DB, a brief list of anesthetic/sedative drugs, such as haloperidol, ketamine, lidocaine, midazolam, propofol, and valproic acid, are shown to possess anti-cancer properties. Therefore, in the current review, we will provide a general overview of the anti-cancer mechanisms of these anesthetic/sedative drugs and explore the potential underlying signaling pathways and clinical application of these drugs applied individually or in combination with other anti-cancer agents.

Which idea is better with regard to immune response? Opioid anesthesia or opioid free anesthesia

The stress of surgery is characterized by an inflammatory response with immune suppression resulting from many factors, including the type of surgery and the kind of anesthesia, linked with the drugs that are used and the underlying disease of the patient. The trauma of surgery triggers a cascade of reactions involving the immune response and nociception. As strong analgesics, opioids provide the analgesic component of general anesthesia with bi-directional effect on the immune system. Opioids influence almost all aspects of the immune response in regards to leukocytes, macrophages, mast cells, lymphocytes, and NK cells. The suppressive effect of opioids on the immune system is limiting their use, especially in patients with impaired immune response, so the possibility of using multimodal anesthesia without opioids, known as opioid-free anesthesia (OFA), is gaining more and more sympathizers. The idea of OFA is to eliminate opioid analgesia in the treatment of acute pain and to replace it with drugs from other groups that are assumed to have a comparable analgesic effect without affecting the immune system. Here, we present a review on the impact of anesthesia, with and without the use of opioids, on the immune response to surgical stress.

Ketamine exposure during embryogenesis inhibits cellular proliferation in rat fetal cortical neurogenic regions

BACKGROUND

Developmental neurotoxicity of ketamine, an N-methyl-D-aspartate receptor antagonist, must be considered due to its widespread uses for sedation/analgesia/anesthesia in pediatric and obstetric settings. Dose-dependent effects of ketamine on cellular proliferation in the neurogenic regions of rat fetal cortex [ventricular zone (VZ) and subventricular zone (SVZ)] were investigated in this in vivo study.

METHODS

Timed-pregnant Sprague-Dawley rats at embryonic day 17 (E17) were given with different doses of ketamine intraperitoneally (0, 1, 2, 10, 20, 40, and 100 mg/kg). Proliferating cells in the rat fetal brains were labeled by injecting 100 mg/kg of 5-bromo-2'-deoxyuridine (BrdU) intraperitoneally. BrdU-labeled cells were detected by immunostaining methods. The numbers of BrdU-positive cells in VZ and SVZ of rat fetal cortex were employed to quantify proliferation in the developing rat cortex.

RESULTS

Ketamine dose-dependently reduced the number of BrdU-positive cells in VZ (P < 0.001) and SVZ (P < 0.001) of the rat fetal cortex. SVZ showed greater susceptibility to ketamine-induced reduction of proliferation in rat fetal cortex, occurring even at clinically relevant doses (2 mg/kg).

CONCLUSION

These data suggest that exposure to ketamine during embryogenesis can dose-dependently inhibit the cellular proliferation in neurogenic regions of the rat fetal cortex.

Effects of ketamine, s-ketamine, and MK 801 on proliferation, apoptosis, and necrosis in pancreatic cancer cells

Background

Adenocarcinoma of the pancreas is one of the most aggressive cancer diseases affecting the human body. The oncogenic potential of this type of cancer is mainly characterized by its extreme growth rate triggered by the activation of signaling cascades. Modern oncological treatment strategies aim at efficiently modulating specific signaling and transcriptional pathways. Recently, anti-tumoral potential has been proven for several substances that are not primarily used in cancer treatment. In some tumor entities, for example, administration of glutamate antagonists inhibits cell proliferation, cell cycle arrest, and finally cell death.

To attain endogenic proof of NMDA receptor type expression in the pancreatic cancer cell lines PaTu8988t and Panc-1 and to investigate the impact of ketamine, s-ketamine, and the NMDA receptor antagonist MK 801 on proliferation, apoptosis, and necrosis in pancreatic carcinoma.

Methods

Cell proliferation was measured by means of the ELISA BrdU assay, and the apoptosis rate was analyzed by annexin V staining. Immunoblotting were also used.

Results

The NMDA receptor type R2a was expressed in both pancreatic carcinoma cell lines. Furthermore, ketamine, s-ketamine, and MK 801 significantly inhibited proliferation and apoptosis.

Conclusions

In this study, we showed the expression of the NMDA receptor type R2a in pancreatic cancer cells. The NMDA antagonists ketamine, s-ketamine, and MK 801 inhibited cell proliferation and cell death. Further clinical studies are warranted to identify the impact of these agents on the treatment of cancer patients.

The effects of intravenous anesthetics on mouse embryonic fibroblast viability and proliferation

PURPOSE

The aim of this study is to evaluate the cytotoxic and antiproliferating effects of intravenous anesthetics on an mouse fibroblast in vitro cell culture system.

METHODS

The cells were exposed to the usual clinical plasma concentration of intravenous anesthetics, i.e., midazolam (0.15 μg/ml), propofol (2 μg/ml), remifentanil (2 μg/ml), thiopental (10 μg/ml), for 4, 8, or 24 h. Cell proliferation (n = 6 for each) under intravenous anesthetics was analyzed using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Cytotoxicity (n = 6 for each) of intravenous anesthetics was investigated using a LIVE/DEAD viability assay kit.

RESULTS

Intravenous anesthetic exposure time did not affect the proliferation rate of mouse fibroblasts. The cytotoxicity of intravenous anesthetics did not differ in accordance with exposure time.

CONCLUSION

Our results showed that intravenous anesthetics may not affect mouse fibroblast proliferation and viability.

A forskolin derivative, colforsin daropate hydrochloride, inhibits rat mesangial cell mitogenesis via the cyclic AMP pathway

A forskolin derivative, colforsin daropate hydrochloride (CDH), has been introduced as an inotropic agent that acts directly on adenylate cyclase to increase intracellular cyclic AMP (cAMP) levels and ventricular contractility, resulting in positive inotropic activity. We investigated the effects of CDH on rat mesangial cell (MC) proliferation. CDH (10(-7)-10(-5) mol/l) inhibited [(3)H]thymidine incorporation into cultured rat MCs in a concentration-dependent manner. CDH (10(-7)-10(-5) mol/l) also decreased cell numbers in a similar manner, and stimulated cAMP accumulation in MCs in a concentration-dependent manner. A protein kinase A inhibitor, H-89, abolished the inhibitory effects of CDH on MC mitogenesis. These findings suggest that CDH would inhibit the proliferation of rat MCs via the cAMP pathway.

Effects of the intravenously administered anaesthetics ketamine, propofol, and thiamylal on the cortical renal blood flow in rats

Intravenous anaesthetics such as ketamine, propofol, and thiamylal are widely used, although the direct effects of these anaesthetics on the renal blood flow (RBF) have not been well elucidated. In this study, we examined the effects of bolus and continuous administrations of ketamine, propofol, and thiamylal on cortical RBF and the effects of noradrenaline (NA) on RBF under continuous administration of these anaesthetics. We used laser Doppler flowmetry to measure the effects of bolus injection and continuous infusion of ketamine, propofol, and thiamylal on cortical RBF in male Wistar rats. We also examined the effects of the anaesthetics on mean arterial blood pressure (MAP) and heart rate (HR). Bolus injections of ketamine, propofol, or thiamylal (1-8 mg/kg each, n = 10) at clinically relevant concentrations did not affect MAP, HR, or RBF. Continuous administration of ketamine, propofol, or thiamylal (1-8 mg/kg/h each, n = 10) did not affect MAP, HR or RBF. Exogenous NA (2 microg/kg) caused an increase in MAP and a decrease in RBF and HR. In experiments with continuous infusions of propofol or thiamylal (1-8 mg/kg/h each, n = 10), similar results were observed without infusion of any anaesthetics. However, bolus injection of NA did not result in a decrease in RBF during continuous ketamine infusion (98.8 +/- 6.7% of control, n = 6, p < 0.05), while ketamine did not affect the NA-induced increase in MAP. In conclusion, bolus and continuous administrations of ketamine, propofol, and thiamylal did not affect the RBF. From our present findings, ketamine would be useful for maintaining the RBF.

Inhibitory effects of nicorandil on rat mesangial cell proliferation via the protein kinase G pathway

We investigated the effects of nicorandil, which is a hybrid between a nitrate and an ATP-sensitive potassium channel (K(ATP)) opener, on cultured rat mesangial cell proliferation. Nicorandil (1 microM to 1 mM inhibited [(3)H]thymidine incorporation into rat mesangial cells in a concentration-dependent manner. Nicorandil (1 microM to 1 mM) also inhibited the number of cells. Nicorandil increased cyclic guanosine 3',5'-cyclic monophosphate accumulation in mesangial cells. A protein kinase G inhibitor, KT5823, partially eliminated the inhibition of mesangial cell proliferation by nicorandil. Methylene blue, a guanylate cyclase inhibitor, blocked the inhibitory effect of nicorandil on mesangial cell proliferation. We also examined the effects of K(ATP) mediators. Cromakalim, a K(ATP) activator, and glibenclamide, a K(ATP) inhibitor, had little effect on the proliferation of mesangial cells. These results suggest that the inhibitory effects of nicorandil on mesangial cell proliferation are mediated via the protein kinase G pathway.