Central sensitization(CS) is an important factor in inducing neuropathic pain(NPP), and the association between signal transduction protein 1(Epac1) and piezoelectric type mechanosensitive ion channel component 2(Piezo2) is a new and significant pathway for initiating CS. This study whether the central analgesic effect of Maxiong Powder is achieved through the synchronized regulation of the Epac1-Piezo2 signaling pathway in the medial habenular nucleus(MHb) and interpeduncular nucleus(IPN) of the brain. Dynamic in vivo microdialysis, combined with high-performance liquid chromatography-fluorescence detection(HPLC-RFC), behavioral assessments, immunohistochemistry, Western blot, and quantitative reverse transcription PCR, were employed in rats with partial sciatic nerve injury(SNI) to investigate the distribution and expression of Epac1 and Piezo2 proteins and genes in the MHb and IPN regions, and the changes in the extracellular levels of glutamate(Glu), aspartic acid(Asp), and glycine(Gly). Compared with the sham group, rats in the SNI group showed significantly reduced analgesic activity, a significant increase in cold pain sensitivity scores, and elevated Glu levels in the MHb and IPN regions. Additionally, the number of Piezo2-positive cells in these regions, as well as the expression levels of Epac1 and Piezo2 proteins and genes, were significantly increased. Compared with the SNI group, after Maxiong Powder administration, the analgesic activity in rats significantly increased, and cold pain sensitivity scores were significantly reduced. Maxiong Powder also significantly decreased the Glu content in the MHb and IPN regions and the Gly content in the MHb region, while significantly increasing the Asp content in both regions. Furthermore, Maxiong Powder significantly reduced the number of Piezo2-positive cells and lowered the protein and gene expression levels of Epac1 and Piezo2 in both brain regions. The central analgesic effect of Maxiong Powder may be related to its inhibition of Glu and Gly release in the extracellular fluid of the MHb and IPN regions, the increase of Asp levels in these regions, and the regulation of the Epac1-Piezo2 pathway through the reduction of Epac1 and Piezo2 protein and gene expression. These results provide partial scientific evidence for the clinical analgesic efficacy of Maxiong Powder and offer new ideas and approaches for the clinical treatment of NPP.
Animals ; Neuralgia/genetics* ; Rats ; Signal Transduction/drug effects* ; Male ; Rats, Sprague-Dawley ; Guanine Nucleotide Exchange Factors/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Habenula/drug effects* ; Ion Channels/genetics* ; Humans

OBJECTIVES: To explore the therapeutic mechanism of Chaihu Shugan (CHSG) Decoction for improving cognitive impairment in rats with epilepsy induced by lithium chloride and pilocarpine. METHODS: Male SD rat models of cognitive impairment model after epilepsy induced by intraperitoneal injection with lithium chloride and pilocarpine were randomly divided into 5 groups (n=12) for treatment with daily gavage of saline, donepezil (90 mg/kg), or CHSG Decoction at 2.5, 5.0, 10, 20 and 40 g/kg for 4 consecutive weeks, with 10 rats with intraperitoneal injection with saline as the blank control group. Morris water maze test was used to evaluate cognitive and behavioral changes of the rats after treatment. The mRNA and protein expressions of ASIC1, NR1, NR2A and NR2B in the hippocampus of rats were detected using RT-qPCR and Western blotting. RESULTS: Compared with those with saline treatment, the rat models treated with CHSG Decoction at 5 and 10 g/kg showed significantly shortened escape latency and prolonged stay in the target quadrant with increased number of platform crossings in Morris water maze test. CHSG Decoction treatment at the two doses significantly increased ASIC1, NR1, NR2A and NR2B protein expressions in the hippocampus of the rat models, and their mRNA expression levels were all increased significantly after the treatment at the doses above 2.5 g/kg. CONCLUSIONS CHSG Decoction can improve cognitive impairment in rats after epilepsy possibly by regulating the expression and channel activity of NMDAR protein and its subunit protein via upregulating ASIC1 to modulate neuronal excitability and synaptic plasticity in the hippocampus.
Animals ; Hippocampus/drug effects* ; Receptors, N-Methyl-D-Aspartate/metabolism* ; Acid Sensing Ion Channels/metabolism* ; Rats, Sprague-Dawley ; Male ; Rats ; Epilepsy/complications* ; Cognitive Dysfunction/drug therapy* ; Drugs, Chinese Herbal/therapeutic use* ; Up-Regulation ; Maze Learning

OBJECTIVES: To evaluate the inhibitory effect of oridonin against proliferation of pancreatic cancer cells and the mechanism underlying the synergistic effect of low-intensity pulsed ultrasound (LIPUS). METHODS: PANC-1 cells treated with different concentrations of oridonin were examined for changes in cell proliferation using CCK-8 assay and in MDA, GSH and ATP levels using flow cytometry. The protein expressions of GPX4, Nrf2 and HO-1 in the treated cells were detected with Western blotting. The effect of Fer-1, a ferroptosis inhibitor, on proliferation of oridonin-treated cells were assessed, and the effects of oridonin combined with LIPUS on PIEZO1 protein expression was evalauted using Western blotting. A C57BL/6J mouse model bearing pancreatic cancer cell xenograft was established and treated with oridonin, LIPUS, or both, and the histological changes in the tumor tissues and tumor cell proliferation were examined with HE staining and immunohistochemistry for Ki67; the changes in GPX4 expression in the tumor tissues were detected using Western blotting and immunofluorescence staining. RESULTS: In PANC-1 cells, oridonin treatment significantly inhibited cell proliferation, increased intracellular Fe²⁺, ROS, and MDA levels, and decreased GSH and ATP levels. Oridonin also resulted in lowered GPX4 and increased HO-1 and Nrf2 protein expression levels in the cells. The combined treatment with LIPUS signficiantly enhanced the inhibitory effect of oridonin on PANC-1 cell viability in vitro and on xenograft growth in the mouse models, resulting also in more obvious reduction of the intensity of Ki67 staining and GPX4 protein expression and more pronounced increase of PIEZO1 protein expression in the tumor tissues in the mouse models. CONCLUSIONS LIPUS enhances the effect of oridonin to promote ferroptosis of pancreatic cancer cells by activating PIEZO1 through the Nrf2/HO-1/GPX4 pathway.
Ferroptosis/drug effects* ; Animals ; Pancreatic Neoplasms/metabolism* ; NF-E2-Related Factor 2/metabolism* ; Humans ; Cell Line, Tumor ; Mice ; Heme Oxygenase-1/metabolism* ; Diterpenes, Kaurane/pharmacology* ; Cell Proliferation/drug effects* ; Mice, Inbred C57BL ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Ion Channels/metabolism* ; Ultrasonic Waves ; Signal Transduction

This study aims to validate our hypothesis that acid-sensing ion channels (ASICs) may contribute to the symptom of pain in patients with chronic prostatitis (CP). We first established a CP rat model, then isolated the L5-S2 spinal dorsal horn neurons for further studies. ASIC1a was knocked down and its effects on the expression of neurogenic inflammation-related factors in the dorsal horn neurons of rat spinal cord were evaluated. The effect of ASIC1a on the Ca²⁺ ion concentration in the dorsal horn neurons of rat spinal cord was measured by the intracellular calcium ([Ca²⁺]i) intensity. The effect of ASIC1a on the p38/mitogen-activated protein kinase (MAPK) signaling pathway was also determined. ASIC1a was significantly upregulated in the CP rat model as compared with control rats. Acid-induced ASIC1a expression increased [Ca²⁺]i intensity in the dorsal horn neurons of rat spinal cord. ASIC1a also increased the levels of neurogenic inflammation-related factors and p-p38 expression in the acid-treated dorsal horn neurons. Notably, ASIC1a knockdown significantly decreased the expression of pro-inflammatory cytokines. Furthermore, the levels of p-p38 and pro-inflammatory cytokines in acid-treated dorsal horn neurons were significantly decreased in the presence of PcTx-1, BAPTA-AM, or SB203580. Our results showed that ASIC1a may contribute to the symptom of pain in patients with CP, at least partially, by regulating the p38/MAPK signaling pathway.
Acid Sensing Ion Channel Blockers/pharmacology* ; Acid Sensing Ion Channels/genetics* ; Animals ; Calcium/metabolism* ; Chelating Agents/pharmacology* ; Chronic Disease ; Cytokines/metabolism* ; Disease Models, Animal ; Egtazic Acid/pharmacology* ; Gene Knockdown Techniques ; Imidazoles/pharmacology* ; Inflammation/metabolism* ; MAP Kinase Signaling System/genetics* ; Male ; Pain/genetics* ; Peptides/pharmacology* ; Phosphorylation/drug effects* ; Posterior Horn Cells/metabolism* ; Prostatitis/complications* ; Protein Kinase Inhibitors/pharmacology* ; Pyridines/pharmacology* ; Rats ; Spider Venoms/pharmacology* ; Up-Regulation ; p38 Mitogen-Activated Protein Kinases/metabolism*

Swelling-activated chloride currents (ICl.swell) are thought to play a role in several physiologic and pathophysiologic processes and thus represent a target for therapeutic approaches. However, the mechanism of ICl.swell regulation remains unclear. In this study, we used the whole-cell patch-clamp technique to examine the role of protein kinase C (PKC) in the regulation of ICl.swell in human atrial myocytes. Atrial myocytes were isolated from the right atrial appendages of patients undergoing coronary artery bypass and enzymatically dissociated. ICl.swell was evoked in hypotonic solution and recorded using the whole-cell patch-clamp technique. The PKC agonist phorbol dibutyrate (PDBu) enhanced ICl.swell in a concentration-dependent manner, which was reversed in isotonic solution and by a chloride current inhibitor, 9-anthracenecarboxylicacid. Furthermore, the PKC inhibitor bis-indolylmaleimide attenuated the effect and 4α-PDBu, an inactive PDBu analog, had no effect on ICl.swell. These results, obtained using the whole-cell patch-clamp technique, demonstrate the ability of PKC to activate ICl,swell in human atrial myocytes. This observation was consistent with a previous study using a single-channel patch-clamp technique, but differed from some findings in other species.
Anthracenes ; pharmacology ; Chloride Channels ; metabolism ; Chlorides ; agonists ; antagonists & inhibitors ; metabolism ; Culture Media ; metabolism ; pharmacology ; Dose-Response Relationship, Drug ; Evoked Potentials ; drug effects ; physiology ; Heart Atria ; cytology ; drug effects ; metabolism ; Humans ; Hypotonic Solutions ; metabolism ; pharmacology ; Indoles ; pharmacology ; Ion Transport ; drug effects ; Maleimides ; pharmacology ; Myocytes, Cardiac ; cytology ; drug effects ; metabolism ; Patch-Clamp Techniques ; Phorbol 12,13-Dibutyrate ; pharmacology ; Primary Cell Culture ; Protein Kinase C ; metabolism

OBJECTIVETo explore whether the inhibitory effect of Genipin on uncoupling protein-2 (UCP-2) in mitochondria is involved in energy metabolism of androgen-independent PC3 prostate cancer cells.

METHODSPC3 prostate cancer cells were cultured and treated with Genipin at the concentrations of 40, 80, and 160 μmol/L for 48 hours. Then the proliferation of the cells was detected by MTT assay, the expression of UCP-2 mRNA determined by RT-PCR, and the content of intracellular pyruvic acid (PA) and the activity of succinate dehydrogenase (SDH) in the mitochondria measured by visible spectrophotometry.

RESULTSWith the increased concentration of Genipin, the proliferative activity of the PC-3 cells, the expression level of UCP-2 mRNA, the content of intracellular PA and the activity of SDH in the cells were all decreased, namely, with the enhanced inhibitory effect of Genipin on UCP-2, a trend of reduction was observed in the proliferation of the cells, intracellular PA content, and SDH activity in the mitochondria.

CONCLUSIONGenipin is involved in the energy metabolism of androgen-independent PC3 prostate cancer cells by reducing the content of intracellular PA and the activity of SDH in the mitochondria, which may be associated with its inhibitory effect on UCP-2.

Cell Line, Tumor ; drug effects ; Energy Metabolism ; Humans ; Ion Channels ; metabolism ; Iridoids ; pharmacology ; Male ; Mitochondria ; metabolism ; Mitochondrial Proteins ; metabolism ; Prostatic Neoplasms ; metabolism ; Pyruvic Acid ; metabolism ; RNA, Messenger ; Succinate Dehydrogenase ; metabolism ; Uncoupling Protein 2

OBJECTIVETo investigate activation of brown adipose tissue (BAT) stimulated by medium-chain triglyceride (MCT).

METHODS30 Male C57BL/6J obese mice induced by fed high fat diet (HFD) were divided into 2 groups, and fed another HFD with 2% MCT or long-chain triglyceride (LCT) respectively for 12 weeks. Body weight, blood biochemical variables, interscapular brown fat tissue (IBAT) mass, expressions of mRNA and protein of beta 3-adrenergic receptors (β3-AR), uncoupling protein-1 (UCP1), hormone sensitive lipase (HSL), protein kinase A (PKA), and adipose triglyceride lipase (ATGL) in IBAT were measured.

RESULTSSignificant decrease in body weight and body fat mass was observed in MCT group as compared with LCT group (P<0.05) after 12 weeks. Greater increases in IBAT mass was observed in MCT group than in LCT group (P<0.05). Blood TG, TC, LDL-C in MCT group were decreased significantly, meanwhile blood HDL-C, ratio of HDL-C/LDL-C and norepinephrine were increased markedly. Expressions of mRNA and protein of β3-AR, UCP1, PKA, HSL, ATGL in BAT were greater in MCT group than in LCT group (P<0.05).

CONCLUSIONOur results suggest that MCT stimulated the activation of BAT, possible via norepinephrine pathway, which might partially contribute to reduction of the body fat mass in obese mice fed high fat diet.

Adipose Tissue, Brown ; drug effects ; Adiposity ; drug effects ; Animals ; Dietary Fats ; administration & dosage ; pharmacology ; Ion Channels ; genetics ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mitochondrial Proteins ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Triglycerides ; chemistry ; pharmacology ; Uncoupling Protein 1 ; Weight Loss

Chlorogenic acid (5-caffeoylquinic acid, CGA) is a phenolic compound that is found ubiquitously in plants, fruits and vegetables and is formed via the esterification of caffeic acid and quinic acid. In addition to its notable biological functions against cardiovascular diseases, type-2 diabetes and inflammatory conditions, CGA was recently hypothesized to be an alternative for the treatment of neurological diseases such as Alzheimer's disease and neuropathic pain disorders. However, its mechanism of action is unclear. Voltage-gated potassium channel (Kv) is a crucial factor in the electro-physiological processes of sensory neurons. Kv has also been identified as a potential therapeutic target for inflammation and neuropathic pain disorders. In this study, we analysed the effects of CGA on the two main subtypes of Kv in trigeminal ganglion neurons, namely, the IK,A and IK,V channels. Trigeminal ganglion (TRG) neurons were acutely disassociated from the rat TRG, and two different doses of CGA (0.2 and 1 mmol⋅L(-1)) were applied to the cells. Whole-cell patch-clamp recordings were performed to observe alterations in the activation and inactivation properties of the IK,A and IK,V channels. The results demonstrated that 0.2 mmol⋅L(-1) CGA decreased the peak current density of IK,A. Both 0.2 mmol⋅L(-1) and 1 mmol⋅L(-1) CGA also caused a significant reduction in the activation and inactivation thresholds of IK,A and IK,V. CGA exhibited a strong effect on the activation and inactivation velocities of IK,A and IK,V. These findings provide novel evidence explaining the biological effects of CGA, especially regarding its neurological effects.
Analgesics ; pharmacology ; Animals ; Animals, Newborn ; Cell Culture Techniques ; Chlorogenic Acid ; administration & dosage ; pharmacology ; Ion Channel Gating ; drug effects ; Membrane Potentials ; drug effects ; Neurons ; drug effects ; Neurotransmitter Agents ; administration & dosage ; pharmacology ; Patch-Clamp Techniques ; Potassium Channels, Voltage-Gated ; drug effects ; Rats ; Rats, Sprague-Dawley ; Trigeminal Ganglion ; drug effects

Cardiotrophin-1 (CT-1) activates a distinct form of cardiac muscle cell hypertrophy in which the sarcomeric units are assembled in series. The aim of the study was to determine the expression pattern of sarcomeric contractile protein α-actin, specialized cytoskeletal protein α-actinin and mitochondrial uncoupling protein-2 (UCP2) in myocardial remodeling induced by chronic exposure to CT-1. Kunming mice were intraperitoneally injected with carboxy-terminal polypeptide (CP) of CT-1 (CT-1-CP, 500 μg·kg(-1)· day(-1)) for 1, 2, 3 and 4 week (s), respectively (4 groups obtained according to the injection time, n=10 each, with 5 males and 5 females in each group). Those injected with physiological saline for 4 weeks served as controls (n=10, with 5 males and 5 females). The heart tissues of mice were harvested at 1, 2, 3 or 4 week (s). Immunohistochemistry (IHC) and Western blotting (WB) were used to detect the distribution and expression of sarcomeric α-actin, α-actinin and mitochondrial UCP2 in myocardial tissues. IHC showed that α-actin was mainly distributed around the nuclei of cardiomyocytes, α-actinin concentrated around the striae and UCP2 scattered rather evenly in the plasma. The expression of α-actin was slightly greater than that of α-actinin and UCP2 in the control group (IHC: χ(2)=6.125; WB: F=0.249, P>0.05) and it gradually decreased after exposure to CT-1-CP. There was no significant difference in the expression of α-actin between the control group and the CT-1-CP-treated groups (χ (2)=7.386, P>0.05). But Western blotting revealed significant difference in the expression of α-actin between the control group and the 4-week CT-1-CP-treated group (F=2.912; q=4.203, P<0.05). Moreover, it was found that the expression of α-actinin increased stepwise with the exposure time in CT-1-CP-treated groups and differed significantly between CT-1-CP-treated groups and the control group (ICH: χ (2)=21.977; WB: F=50.388; P<0.01). The expression of UCP2 was initially increased (WB: control group vs. 1- or 2-week group, q values: 5.603 and 9.995, respectively, P<0.01) and then decreased (WB: control group vs. 3-week group, q=4.742, P<0.01; control group vs. 4-week group, q=0.558, P>0.05). It was suggested that long-term exposure to CT-1-CP could lead to the alteration in the expression of sarcomeric α-actin, α-actinin and mitochondrial UCP2. The different expressions of sarcomeric structure proteins and mitochondrial UCP2 may be involved in myocardial remodeling.
Actinin ; biosynthesis ; Actins ; biosynthesis ; Animals ; Cardiomegaly ; chemically induced ; metabolism ; pathology ; Cytokines ; adverse effects ; pharmacology ; Female ; Gene Expression Regulation ; drug effects ; Ion Channels ; biosynthesis ; Male ; Mice ; Mitochondrial Proteins ; biosynthesis ; Myocardium ; metabolism ; pathology ; Sarcomeres ; metabolism ; pathology ; Uncoupling Protein 2

FXYD6, FXYD domain containing ion transport regulator 6, has been reported to affect the activity of Na(+)/K(+)-ATPase and be associated with mental diseases. Here, we demonstrate that FXYD6 is up-regulated in hepatocellular carcinoma (HCC) and enhances the migration and proliferation of HCC cells. Up-regulation of FXYD6 not only positively correlates with the increase of Na(+)/K(+)-ATPase but also coordinates with the activation of its downstream Src-ERK signaling pathway. More importantly, blocking FXYD6 by its functional antibody significantly inhibits the growth potential of the xenografted HCC tumors in mice, indicating that FXYD6 represents a potential therapeutic target toward HCC. Altogether, our results establish a critical role of FXYD6 in HCC progression and suggest that the therapy targeting FXYD6 can benefit the clinical treatment toward HCC patients.
Animals ; Antibodies, Monoclonal ; pharmacology ; Antineoplastic Agents ; pharmacology ; Carcinoma, Hepatocellular ; drug therapy ; metabolism ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Female ; HEK293 Cells ; Humans ; Ion Channels ; antagonists & inhibitors ; metabolism ; Liver Neoplasms ; drug therapy ; metabolism ; Mice, Inbred BALB C ; Mice, Nude ; Sodium-Potassium-Exchanging ATPase ; metabolism ; Tumor Burden ; drug effects ; Xenograft Model Antitumor Assays