Potential ; Bale out

Transient receptor potential (TRP) channels, a large family of receptor channel proteins, initially attracted researchers in the pain field as key molecules in nociception, but later they became known as more general transducer molecules for various physical stresses. In this review, I will discuss their roles in thermal and mechanical sensation, and then consider their contribution to physiological pain.
Humans ; Nociception ; Proteins ; Sensation ; Transducers ; Transient Receptor Potential Channels

Humans ; Hypertension ; metabolism ; pathology ; Transient Receptor Potential Channels ; metabolism ; physiology

PURPOSE: Lipophilic cations including tetraphenylphosphonium (TPP) salts penetrate the hydrophobic barriers of the plasma and mitochondrial membranes, resulting in accumulation in mitochondria in response to the negative inner transmembrane potentials. The development of radiolabeled phosphonium cations as a noninvasive imaging agent may serve as a new molecular "voltage sensor" probe to investigate the role of mitochondria in the pathophysiology and diagnosis of cancer. MATERIALS AND METHODS: We have synthesized a reference compound (4-fluorophenyl)triphenylphosphonium (TPP) and a labeled compound [18F]TPP via two step nucleophilic substitution of no-carrier-added [18F]fluoride with the precursor, 4-iodophenyltrimethylammonium iodide, in the presence of Kryptofix-2.2.2 and K2CO3. RESULT: The reference compound (4-fluorophenyl)triphenylphosphonium (TPP) was synthesized in 60% yield. The radiolabeled compound [18F]TPP was synthesized in 10~15% yield. The radiochemical purity of the [18F]TPP was 95.57+/-0.51% (n=11). CONCLUSION: [18F]TPP was successfully synthesized that might have a potential to be utilized as a novel myocardial or cancer imaging agent for PET. However, it is required to improve the radiochemical yield to apply [18F]TPP in preclinical or clinical researches.
Cations ; Diagnosis ; Membrane Potential, Mitochondrial ; Membrane Potentials ; Mitochondria ; Mitochondrial Membranes ; Plasma ; Salts

Nanosecond pulsed electric field ablation has been widely applied in clinical cancer treatment, while its molecular mechanism is still unclear. Researchers have revealed that nanosecond pulsed electric field generates nanopores in plasma membrane, leading to a rapid influx of Ca²⁺; it has specific effect on intracellular organelle membranes, resulting in endoplasmic reticulum injuries and mitochondrial membrane potential changes. In addition, it may also change cellular morphology through damage of cytoskeleton. This article reviews the recent research advances on the molecular mechanism of cell membrane and organelle changes induced by nanosecond pulsed electric field ablation.
Ablation Techniques ; Calcium ; Cell Membrane ; physiology ; Cytoskeleton ; Electricity ; Endoplasmic Reticulum ; Humans ; Membrane Potential, Mitochondrial ; Neoplasms ; therapy

Fucodiphlorethol G (6'-[2,4-dihydroxy-6-(2,4,6-trihydroxyphenoxy)phenoxy]biphenyl-2,2',4,4',6-pentol) is a compound purified from Ecklonia cava, a brown alga that is widely distributed offshore of Jeju Island. This study investigated the protective effects of fucodiphlorethol G against oxidative damage-mediated apoptosis induced by ultraviolet B (UVB) irradiation. Fucodiphlorethol G attenuated the generation of 2, 2-diphenyl-1-picrylhydrazyl radicals and intracellular reactive oxygen species in response to UVB irradiation. Fucodiphlorethol G suppressed the inhibition of human keratinocyte growth by UVB irradiation. Additionally, the wavelength of light absorbed by fucodiphlorethol G was close to the UVB spectrum. Fucodiphlorethol G reduced UVB radiation-induced 8-isoprostane generation and DNA fragmentation in human keratinocytes. Moreover, fucodiphlorethol G reduced UVB radiation-induced loss of mitochondrial membrane potential, generation of apoptotic cells, and active caspase-9 expression. Taken together, fucodiphlorethol G protected human keratinocytes against UVB radiation-induced cell damage and apoptosis by absorbing UVB radiation and scavenging reactive oxygen species.
Apoptosis ; Caspase 9 ; DNA Fragmentation ; Humans ; Keratinocytes ; Membrane Potential, Mitochondrial ; Oxidative Stress* ; Reactive Oxygen Species

Ceramide induces cell death in a dose- and time-dependent manner in neuroblastoma SK-N-SH cells. To investigate the mechanism of SK-N-SH cell death by C2-ceramide, morphological features and Hoechst 33258 staining were analyzed. In these morphlogic study the cell death by ceramide showed typical apoptotic features, nuclear condensation, fragmentation, and membrane blebbing. Ceramide-induced apoptosis was accompanied by nuclear accumulation of p53. Inhibition of p53 expression with p53 antisense oligonucleotides inhibited apoptosis evoked by ceramide. Also, ceramide induced mitochondrial event, collapse of mitochondrial membrane potential (delta psi m) and interestingly, inhibition of p53 attenuated collapse of mitochondrial membrane potential, suggests that ceramide induces mitochondrial dysfunction through upregulation of p53 expression. These results suggest that ceramide-induced apoptosis is dependent upon increase in cellular p53 levels which play a critical role in the regulation of apoptotic cell death and p53 modulates mitochondrial function such as mitochondrial membrane potential level.
Apoptosis ; Bisbenzimidazole ; Blister ; Cell Death* ; Membrane Potential, Mitochondrial ; Membranes ; Neuroblastoma ; Neurons* ; Oligonucleotides, Antisense ; Up-Regulation

OBJECTIVETo investigate the protective effect of ulinastatin against the activation of tourniquet-induced platelet mitochondria apoptotic signaling.

METHOD44 patients with unilateral lower limb operation and tourniquet application were randomly divided into normal saline group and ulinastatin group, and were treated with normal saline and ulinastatin respectively. 12 patents with unilateral lower limb operation but without tourniquet application were enrolled in control group. Lipid hydroperoxide (LPO) in serum was detected by LPO assay kit, the content of ATP was examined by fluorescein-luciferase assay kit; the change of mitochondrial membrane potential (Δ ψm) was detected by JC-1 mitochondrial membrane potential kit; the content of cytoplasmic cytochrome C was examined by Cytochrome C ELISA kit; Caspase-3 activity was detected by Caspase-3 fluorometric assay kit.

RESULTSAs compared with control group, the patients in normal saline group exhibited significant platelet mitochondrial dysfunction which characterized by low ATP level and low mitochondrial membrane potential (Δ ψm) (P < 0.05). Tourniquet application resulted in the activation of the mitochondria apoptotic signaling in platelet, displaying increase in the serum LPO level, release of mitochondrial cytochrome C into the cytoplasm, and activation of caspase-3 (P < 0.05). These alterations above-mentioned were obviously improved by ulinastatin treatment (P < 0.05).

CONCLUSIONTourniquet induces platelet mitochondrial dysfunction and mitochondria-dependent apoptotic signaling activation, which can be improved by ulinastatin treatment.

Apoptosis ; Blood Platelets ; Caspase 3 ; Cytochromes c ; Glycoproteins ; Humans ; Membrane Potential, Mitochondrial ; Mitochondria ; Signal Transduction ; Tourniquets

Excessive use of alcohol is a serious problem in our society and induces various, severe alcohol related diseases. The cytotoxicities of ethanol are still largely unknown. We studied the molecular mechanisms of EtOH-induced SK-N-SH neuronal cell death and protective effects of baicalein and gramineus against EtOH-induced cytotoxicities. In our results, the cell death by EtOH showed morphologic features of apoptosis like as membrane blebbing, nuclear condensation and fragmentation. Furthermore, pretreated baicalein attenuated EtOH-induced neuronal cell death effectively. EtOH increased expression levels of p53 and both p53 antisense oligonucleotide and Pifithrin protected the cell death against EtOH. Also, EtOH induced mitochondrial event, collapse of mitochondrial membrane potential ( delta psi m ) and caspase cascade as a downstream of mitochondria. Interestingly, baicalein decreased expression levels of p53 and inhibited collapse of mitochondrial membrane potential. These results suggest that baicalein reduces mitochondrial dysfunction induced by EtOH through down-regulation of p53 expression levels. Also, baicalein attenuated activation of caspase, which was triggered by mitochondrial malfunction. But gramineus didn't have any protective effect. These results imply that baicalein significantly protects EtOH-induced neuronal cell death through regulating p53, mitochondrial dysfunction and caspase activation.
Apoptosis ; Blister ; Cell Death* ; Down-Regulation ; Ethanol ; Membrane Potential, Mitochondrial ; Membranes ; Mitochondria ; Neurons* ; Signal Transduction*

Excessive use of alcohol is a serious problem in our society and induces various, severe alcohol related diseases. The cytotoxicities of ethanol are still largely unknown. We studied the molecular mechanisms of EtOH-induced SK-N-SH neuronal cell death and protective effects of baicalein and gramineus against EtOH-induced cytotoxicities. In our results, the cell death by EtOH showed morphologic features of apoptosis like as membrane blebbing, nuclear condensation and fragmentation. Furthermore, pretreated baicalein attenuated EtOH-induced neuronal cell death effectively. EtOH increased expression levels of p53 and both p53 antisense oligonucleotide and Pifithrin protected the cell death against EtOH. Also, EtOH induced mitochondrial event, collapse of mitochondrial membrane potential ( delta psi m ) and caspase cascade as a downstream of mitochondria. Interestingly, baicalein decreased expression levels of p53 and inhibited collapse of mitochondrial membrane potential. These results suggest that baicalein reduces mitochondrial dysfunction induced by EtOH through down-regulation of p53 expression levels. Also, baicalein attenuated activation of caspase, which was triggered by mitochondrial malfunction. But gramineus didn't have any protective effect. These results imply that baicalein significantly protects EtOH-induced neuronal cell death through regulating p53, mitochondrial dysfunction and caspase activation.
Apoptosis ; Blister ; Cell Death* ; Down-Regulation ; Ethanol ; Membrane Potential, Mitochondrial ; Membranes ; Mitochondria ; Neurons* ; Signal Transduction*