The changes of nociception and the signal molecules expression in the dorsal root ganglia and the spinal cord after cold water swimming stress in mice.

Several studies have previously reported that exposure to stress provokes behavioral changes, including antinociception, in rodents. In the present study, we studied the effect of acute cold-water (4°C) swimming stress (CWSS) on nociception and the possible changes in several signal molecules in male ICR mice. Here, we show that 3 min of CWSS was sufficient to produce antinociception in tailflick, hot-plate, von-Frey, writhing, and formalin-induced pain models. Significantly, CWSS strongly reduced nociceptive behavior in the first phase, but not in the second phase, of the formalin-induced pain model. We further examined some signal molecules' expressions in the dorsal root ganglia (DRG) and spinal cord to delineate the possible molecular mechanism involved in the antinociceptive effect under CWSS. CWSS reduced p-ERK, p-AMPKα1, p-AMPKα2, p-Tyk2, and p-STAT3 expression both in the spinal cord and DRG. However, the phosphorylation of mTOR was activated after CWSS in the spinal cord and DRG. Moreover, p-JNK and p-CREB activation were significantly increased by CWSS in the spinal cord, whereas CWSS alleviated JNK and CREB phosphorylation levels in DRG. Our results suggest that the antinociception induced by CWSS may be mediated by several molecules, such as ERK, JNK, CREB, AMPKα1, AMPKα2, mTOR, Tyk2, and STAT3 located in the spinal cord and DRG.

Combination of metformin/efavirenz/fluoxetine exhibits profound anticancer activity via a cancer cell-specific ROS amplification.

The possible anticancer activity of combination (M + E + F) of metformin (M), efavirenz (E), and fluoxetine (F) was investigated in normal HDF cells and HCT116 human colon cancer cells. Metformin increased cellular FOXO3a, p-FOXO3a, AMPK, p-AMPK, and MnSOD levels in HDFs but not in HCT116 cells. Cellular ATP level was decreased only in HDFs by metformin. Metformin increased ROS level only in HCT116 cells. Transfection of si-FOXO3a into HCT116 reversed the metformin-induced cellular ROS induction, indicating that FOXO3a/MnSOD is the key regulator for cellular ROS level. Viability readout with M, E, and F alone decreased slightly, but the combination of three drugs dramatically decreased cell survival in HCT116, A549, and SK-Hep-1 cancer cells but not in HDF cells. ROS levels in HCT116 cells were massively increased by M + E + F combination, but not in HDF cells. Cell cycle analysis showed that of M + E + F combination caused cell death only in HCT116 cells. The combination of M + E + F reduced synergistically mitochondrial membrane potential and mitochondrial electron transport chain complex I and III activities in HCT116 cells when compared with individual treatments. Western blot analysis indicated that DNA damage, apoptosis, autophagy, and necroptosis-realated factors increased in M + E + F-treated HCT116 cells. Oral administration with M + E + F combination for 3 weeks caused dramatic reductions in tumor volume and weight in HCT116 xenograft model of nude mice when compared with untreated ones. Our results suggest that M + E + F have profound anticancer activity both in vitro and in vivo via a cancer cell-specific ROS amplification (CASRA) through ROS-induced DNA damage, apoptosis, autophagy, and necroptosis.

The mixture of Agrimonia pilosa Ledeb. and Salvia miltiorrhiza Bunge. extract produces analgesic and anti-inflammatory effects in a collagen-induced arthritis mouse model.

Pain and inflammation typically manifest in patients with arthritis. It is now widely known that Agrimonia pilosa Ledeb (AP) and Salvia miltiorrhiza Bunge (SM) exert anti-inflammatory and antinociceptive effects. We have previously reported that the mixture extract (ME) from AP and SM produces antinociceptive and anti-inflammatory effects in gout arthritis and monoiodoacetate (MIA)-induced arthritis models. In the present study, we assessed the antinociceptive and anti-inflammatory effects on the collagen-induced arthritis (CIA) model. The antinociceptive effects in mice were measured using the von Frey test. ME administered once or for one week (once per day) once, and one-week reduced the pain in a dose-dependent manner (from 50 to 100 mg/kg) in the CIA-induced osteoarthritis (OA) model. ME treatment also reduced tumor necrosis factor (TNF)-α and C-reactive protein (CRP) levels in plasma and ankle tissues. Furthermore, COX-1, COX-2, NF-κB, TNF-α, and IL-6 expressions were attenuated after ME treatment. In most experiments, the antinociceptive and anti-inflammatory effects induced by ME treatment were almost equal to or slightly better than those induced by Perna canaliculus (PC) treatment, which was used as a positive control. Our results suggest that ME possesses antinociceptive and anti-inflammatory effects, indicating its potential as a therapeutic agent for arthritis treatment.

Modulation of corticosterone and changes of signal molecules in the HPA axis after cold water swimming stress.

In the present study, we examined the effect of cold-water swimming stress (CWSS) on plasma corticosterone levels. Mice were exposed to stress in 4°C for 3 mins. Plasma corticosterone (CORT) level was measured at 0, 15, and 30 min after stress stimulation. The plasma CORT level was gradually increased up to 30 min. Then we further examined the changes of several signaling molecules expression levels, such as p-ERK, p-JNK, p-P38, p-AMPKα1, p-AMPKα2, and p-mTOR, in the HPA axis. We observed that those signaling molecules were altered after stress in the HPA axis. p-ERK, p-JNK, p-P38, and p-mTOR proteins expression were reduced by CWSS in the HPA axis. However, the phosphorylation of AMPKα1 and AMPKα2 were activated after CWSS in the HPA axis. Our results suggest that the upregulation of plasma CORT level induced by CWSS may be modulated by the those signaling molecules.

Metformin-induced ROS upregulation as amplified by apigenin causes profound anticancer activity while sparing normal cells.

Metformin increased cellular ROS levels in AsPC-1 pancreatic cancer cells, with minimal effect in HDF, human primary dermal fibroblasts. Metformin reduced cellular ATP levels in HDF, but not in AsPC-1 cells. Metformin increased AMPK, p-AMPK (Thr172), FOXO3a, p-FOXO3a (Ser413), and MnSOD levels in HDF, but not in AsPC-1 cells. p-AMPK and p-FOXO3a also translocated from the cytosol to the nucleus by metformin in HDF, but not in AsPC-1 cells. Transfection of si-FOXO3a in HDF increased ROS levels, while wt-FOXO3a-transfected AsPC-1 cells decreased ROS levels. Metformin combined with apigenin increased ROS levels dramatically and decreased cell viability in various cancer cells including AsPC-1 cells, with each drug used singly having a minimal effect. Metformin/apigenin combination synergistically decreased mitochondrial membrane potential in AsPC-1 cells but to a lesser extent in HDF cells. Metformin/apigenin combination in AsPC-1 cells increased DNA damage-, apoptosis-, autophagy- and necroptosis-related factors, but not in HDF cells. Oral administration with metformin/apigenin caused dramatic blocks tumor size in AsPC-1-xenografted nude mice. Our results suggest that metformin in cancer cells differentially regulates cellular ROS levels via AMPK-FOXO3a-MnSOD pathway and combination of metformin/apigenin exerts anticancer activity through DNA damage-induced apoptosis, autophagy and necroptosis by cancer cell-specific ROS amplification.

The Anti-Inflammatory and the Antinociceptive Effects of Mixed Agrimonia pilosa Ledeb. and Salvia miltiorrhiza Bunge Extract.

Arthritis is a common condition that causes pain and inflammation in a joint. Previously, we reported that the mixture extract (ME) from Agrimonia pilosa Ledeb. (AP) and Salvia miltiorrhiza Bunge (SM) could ameliorate gout arthritis. In the present study, we aimed to investigate the potential anti-inflammatory and antinociceptive effects of ME and characterize the mechanism. We compared the anti-inflammatory and antinociceptive effects of a positive control, Perna canaliculus powder (PC). The results showed that one-off and one-week treatment of ME reduced the pain threshold in a dose-dependent manner (from 10 to 100 mg/kg) in the mono-iodoacetate (MIA)-induced osteoarthritis (OA) model. ME also reduced the plasma TNF-α, IL-6, and CRP levels. In LPS-stimulated RAW 264.7 cells, ME inhibited the release of NO, PGE2, LTB4, and IL-6, increased the phosphorylation of PPAR-γ protein, and downregulated TNF-α and MAPKs proteins expression in a concentration-dependent (from 1 to 100 µg/mL) manner. Furthermore, ME ameliorated the progression of ear edema in mice. In most of the experiments, ME-induced effects were almost equal to, or were higher than, PC-induced effects. Conclusions: The data presented here suggest that ME shows anti-inflammatory and antinociceptive activities, indicating ME may be a potential therapeutic for arthritis treatment.

The modulatory role of ß­amyloid in the regulation of nociception in mice.

ß-amyloid is an important factor in the pathophysiology of Alzheimer's disease. This study investigates ß-amyloid's role in the regulation of nociception in mice. Pretreated once, 2 weeks prior to testing with ß-amyloid, male ICR mice were examined on various nociceptive tests. Pretreatment with ß-amyloid reversed the nociceptive effects induced by intraperitoneally administered acetic acid (writhing response) and intraplantar injection of 5% formalin into the hind paw. ß-amyloid pretreatment also elevated the threshold for nociception in the mechanical von Frey test. Additionally, p-CREB and p-ERK levels in the spinal cord and the adrenal gland increased after formalin injection. Pretreatment with ß-amyloid attenuated formalin­induced overexpression of p-CREB and p-ERK in the spinal cord and the adrenal gland. Our results suggest that chemical and mechanical nociception appear to be altered in ß-amyloid-treated animals. Furthermore, the reduction of nociception by ß-amyloid in the formalin pain model appears to be mediated, at least in part, by the suppression of p-CREB and p-ERK level in the spinal cord and the adrenal gland.

Antinociceptive effect of chrysin in diabetic neuropathy and formalin-induced pain models.

Chrysin, a natural flavonoid, is the main ingredient of many medicinal plants, which shows potent pharmacological properties. In the present study, the antinociceptive effects of chrysin were examined in ICR mice. Chrysin orally administered at the doses of from 10 to 100 mg/kg exerted the reductions of formalin-induced pain behaviors observed during the second phase in the formalin test in a dose-dependent manner. In addition, the antinociceptive effect of chrysin was further characterized in streptozotocin-induced diabetic neuropathy model. Oral administration chrysin caused reversals of decreased pain threshold observed in diabetic-induced peripheral neuropathy model. Intraperitoneally (i.p.) pretreatment with naloxone (a classic opioid receptor antagonist), but not yohimbine (an antagonist of α2-adrenergic receptors) or methysergide (an antagonist of serotonergic receptors), effectively reversed chrysin-induced antinociceptive effect in the formalin test. Moreover, chrysin caused a reduction of formalin-induced up-regulated spinal p-CREB level, which was also reversed by i.t. pretreated naloxone. Finally, chrysin also suppressed the increase of the spinal p-CREB level induced by diabetic neuropathy. Our results suggest that chrysin shows an antinociceptive property in formalin-induced pain and diabetic neuropathy models. In addition, spinal opioid receptors and CREB protein appear to mediate chrysin-induced antinociception in the formalin-induced pain model.

Brain Proteomic Profiling in Intractable Epilepsy Caused by TSC1 Truncating Mutations: A Small Sample Study.

Tuberous sclerosis complex (TSC) is a genetic disease characterized by seizures, mental deficiency, and abnormalities of the skin, brain, kidney, heart, and lungs. TSC is inherited in an autosomal dominant manner and is caused by variations in either the TSC1 or TSC2 gene. TSC-related epilepsy (TRE) is the most prevalent and challenging clinical feature of TSC, and more than half of the patients have refractory epilepsy. In clinical practice, we found several patients of intractable epilepsy caused by TSC1 truncating mutations. To study the changes of protein expression in the brain, three cases of diseased brain tissue with TSC1 truncating mutation resected in intractable epilepsy operations and three cases of control brain tissue resected in craniocerebral trauma operations were collected to perform protein spectrum detection, and then the data-independent acquisition (DIA) workflow was used to analyze differentially expressed proteins. As a result, there were 55 up- and 55 down-regulated proteins found in the damaged brain tissue with TSC1 mutation compared to the control. Further bioinformatics analysis revealed that the differentially expressed proteins were mainly concentrated in the synaptic membrane between the patients with TSC and the control. Additionally, TSC1 truncating mutations may affect the pathway of amino acid metabolism. Our study provides a new idea to explore the brain damage mechanism caused by TSC1 mutations.

The Molecular Signatures of Acute-immobilization-induced Antinociception and Chronic-immobilization-induced Antinociceptive Tolerance.

In the present study, the productions of antinociception induced by acute and chronic immobilization stress were compared in several animal pain models. In the acute immobilization stress model (up to 1 hr immobilization), the antinociception was produced in writhing, tail-flick, and formalin- induced pain models. In chronic immobilization stress experiment, the mouse was enforced into immobilization for 1 hr/day for 3, 7, or 14 days, then analgesic tests were performed. The antinociceptive effect was gradually reduced after 3, 7 and 14 days of immobilization stress. To delineate the molecular mechanism involved in the antinociceptive tolerance development in the chronic stress model, the expressions of some signal molecules in dorsal root ganglia (DRG), spinal cord, hippocampus, and the hypothalamus were observed in acute and chronic immobilization models. The COX-2 in DRG, p-JNK, p-AMPKα1, and p-mTOR in the spinal cord, p-P38 in the hippocampus, and p-AMPKα1 in the hypothalamus were elevated in acute immobilization stress, but were reduced gradually after 3, 7 and 14 days of immobilization stress. Our results suggest that the chronic immobilization stress causes development of tolerance to the antinociception induced by acute immobilization stress. In addition, the COX-2 in DRG, p-JNK, p-AMPKα1, and p-mTOR in the spinal cord, p-P38 in the hippocampus, and p-AMPKα1 in the hypothalamus may play important roles in the regulation of antinociception induced by acute immobilization stress and the tolerance development induced by chronic immobilization stress.

Effects of resveratrol and oxyresveratrol on hippocampal cell death induced by kainic acid.

In the present study, we have examined the possible neuroprotective effects of resveratrol and oxyresveratrol against kainic-acid (KA)-induced hippocampal neuronal cell death. Either resveratrol or oxyresvertrol was orally administered 30 min prior to intracerebroventricular (i.c.v.) administration with KA (0.05 µg). Oral pretreatment with oxyresveratrol (50 mg/kg) significantly protected KA-induced hippocampal CA3 neuronal cell death. However, the same dose (50 mg/kg) or a higher dose (100 mg/kg) pretreatment with resveratrol did not affect KA-induced hippocampal neuronal cell death. Furthermore, the i.c.v. pretreatment with 30 µg of oxyresveratrol or resveratrol did not show the protective effect against KA-induced hippocampal neuronal cell death. In the immunohistochemical analysis, FoxO3a and pFoxO3a expressions in the hippocampal CA3 region were significantly increased 30 min after KA administration. Oral pretreatment with oxyresveratrol (50 mg/kg) significantly reduced KA-induced Forkhead homeobox type O3a (FoxO3a) and pFoxO3a expression in CA3 region of the hippocampus, suggesting that oxyresveratrol may exert a neuroprotective effect against KA-induced hippocampal neuronal cell death by reducing the levels of FoxO3a and pFoxO3a protein expression in the hippocampal CA3 region. Furthermore, it is suggested that the neuroprotective effect of orally administered oxyresveratrol against KA-induced neurotoxicity might be possibly mediated by some metabolites rather than direct action of oxyresveratrol on the central nervous system.

Antinociceptive effect of N-(9,13b-dihydro-1H-dibenzo[c, f]imidazo[1,5-a]azepin-3-yl)-2-hydroxybenzamide on different pain models in mice

Abstract N-(9,13b-dihydro-1H-dibenzo[c,f]imidazo[1,5-a]azepin-3-yl)-2-hydroxybenzamide (DDIAHB) is a new drug developed through molecular modelling and rational drug design by the molecular association of epinastine and salicylic acid. The present study was designed to assess the possible antinociceptive effects of DDIAHB on different pain models in male ICR mice. DDIAHB exerted the reductions of writhing numbers and pain behavior observed during the second phase in the formalin test in a dose-dependent manner. Moreover, DDIAHB increased the latency in the hot-plate test in a dose-dependent manner. Furthermore, intragastric administration DDIAHB caused reversals of decreased pain threshold observed in both streptozotocin-induced diabetic neuropathy and vincristine-induced peripheral neuropathy models. Additionally, intragastric pretreatment with DDIAHB also caused reversal of decreased pain threshold observed in monosodium urate-induced pain model. We also characterized the possible signaling molecular mechanism of the antinociceptive effect-induced by DDIAHB in the formalin model. DDIAHB caused reductions of spinal iNOS, p-STAT3, p-ERK and p-P38 levels induced by formalin injection. Our results suggest that DDIAHB shows an antinociceptive property in various pain models. Moreover, the antinociceptive effect of DDIAHB appear to be mediated by the reductions of the expression of iNOS, p-STAT3, p-ERK and p-P38 levels in the spinal cord in the formalin-induced pain model.

Hemodynamic effect of apelin in a canine model of acute pulmonary thromboembolism.

The peptide apelin is expressed in the pulmonary vasculature and is involved in the pathogenesis of many cardiovascular diseases. It has a biphasic role in the regulation of vasomotor tone related to the vascular endothelium. In this study, we induced acute pulmonary embolism (APE) in dogs with autologous blood clots to assess the effect of apelin on pulmonary and systemic circulation in the acute phase of APE. The expression of apelin mRNA was found to be upregulated in the lung tissue in the early several hours after APE induction and decreased at 24 h. The expression of apelin protein in the pulmonary arteries did not change within 24 h after APE, but significantly increased in the bronchial epithelial cells as early as 1h and decreased at 24 h. In normal anesthetized dogs, intravenous bolus administration of apelin significantly reduced the mean arterial pressure (MAP), but did not significantly affect the mean pulmonary arterial pressure (MPAP). In the dogs with APE, apelin decreased MPAP, whereas its impact on MAP was not significantly different from that in the control group. Taken together, the level of endogenous apelin did not change significantly in the pulmonary arterial wall, whereas its expression in the bronchial epithelium was upregulated in the early stage of APE. The effect of exogenous apelin on vasomotor tone was complicated: it resulted in differential changes in the pulmonary and systemic arterial pressures under different physiological and pathological conditions.