Establishment of mouse pancreatic ductal organoids and exploration of its physiological functions / 中华胰腺病杂志

Objective:To establish culture system for mouse pancreatic ductal organoids and investigate the morphology and physiological functions of the organoids.Methods:Pancreatic tissues were taken from C57BL/6 mice (6-8 weeks) and digested by collagenase Ⅳ. The pancreatic ducts were separated and collected and then the pancreatic organoids were cultured in the complete medium after Matrix gel embedding. Morphological evaluation of the organoids was performed after hematoxylin-eosin staining. The expression and localization of markers for organoids were identified by Western Blot and immunofluorescence staining; and the expression and localization of ion channels and antimicrobial peptides of the organoids were detected by agarose gel electrophoresis and immunofluorescence staining.Results:Mouse pancreatic organoids were successfully established, which could be stably passaged for 10 generations. The organoids grew spherically and formed a duct-like structure. The internal cavity corresponded to the lumen of pancreatic duct tissue. The pancreatic organoids stably expressed stem progenitor cell marker gene SOX9 and ductal epithelial cell-specific gene KRT19, which were both localized in the epithelium. The organoids did not express amylase. The organoids maintained stable expression of epithelial ion channels Clcn1, Kcnma1, CFTR, Slc12a5, Slc26a3, Slc26a6 and Scnn1a, low expression of Ano1 and no expression of Clcn3, Kcna1, Kcna2, Kcnd3, Kcnh1, Atp12a, Slc4a4, Slc9a1, Slc12a2 and Slc26a11; and CFTR highly expressed in epithelial cells. The organoids maintained high expression of antimicrobial peptides Reg3a, CRAMP and glycoprotein 2, low expression of Defb1, Defb2, and Defb3 and no expression of Defa1 and Defa4; and both CRAMP and Reg3a were expressed in the epithelial cells and secreted into the lumen of the organoids.Conclusions:Mouse pancreatic organoids are successfully established, which can be stably passaged. The organoids maintain the characteristics of ductal epithelial cells and can be used as an in vitro model to study the physiology of pancreatic ducts.

Advances of ultrasonic neuromodulation based on mechanosensitive channels / 生物工程学报

Mechanosensitive channels (MSCs) are special membrane proteins that can convert mechanical stimulation into electrical or chemical signals. These channels have become potential targets for ultrasonic neuromodulation due to their properties. The good spatial resolution and focusing effect of ultrasound make it theoretically possible to achieve non-invasive whole-brain localization. Therefore, ultrasonic neuromodulation is a promising method for performing physical neuromodulation and treating neurological disorders. To date, only a few ion channels have been reported to be activated by ultrasound, while recent research has identified more channels with mechanosensitive properties. Moreover, the opening process and mechanism of MSCs under ultrasound excitation remain unknown. This review provides an overview on recent research advances and applications in MSCs, including large conductance mechanosensitive channels, transient receptor potential channels, degenerated protein/epithelial sodium channels, two-pore potassium channels, and piezo channels. These findings will facilitate future studies and applications of ultrasonic neuromodulation.

D. Julius y A. Patapoutian. Premios Nobel de Medicina 2021, descubren nuevos canales iónicos que detectan temperatura y estímulos mecánicos / D. Julius y A. Patapoutian. 2021 Nobel Prize Awardees discover new ionic channels that detect temperature and mechanical stimuli

D. Julius was awarded the 2021 Medicine Nobel prize for the discovery of new cationic channels that detect temperatures either over 40 °C (TRPV1) or cold (TRPM8) ranging from 8-15 °C, followed by the latter identification of other channels that sense temperatures within other ranges. On the other hand, A. Patapoutian shared the 2021 Nobel prize for the independent and simultaneous co-discovery of the TRPM8 cationic channel. Furthermore, Patapoutian iden-tified piezo 1 and 2 channels previously referred to as the cell mechanosensors related to the sense of touch and proprioception. These experimental findings indicate that these novel cationic channels localized in nerve endings of the skin, mouth, lips, bronchial tree, the nephron, plus a variety of tissues transduce phy-sical stimuli into electrical activity that reach the brain sensory cortex to process these stimuli and elicit animal behavior.

Research progress on familial episodic pain syndrome / 中华神经科杂志

Familial episodic pain syndrome is characterized by ion channel gene mutation in dorsal root ganglion neurons, and there can be neuropathic pain in different parts. However, the lack of awareness of familial episodic pain syndrome, along with the absence of uniform diagnostic and treatment standards, may lead to frequent missed diagnosis and misdiagnosis. This article will review the concepts, classification, pathogenesis, clinical features, diagnosis and treatment of familial episodic pain syndrome, aimed at deepening the understanding of the diseases as well as facilitating early diagnosis and treatment.

Dahuang zhechong pills regulate ASICla/VEGF pathway and alleviate hepatic fibrosis / 中国药理学通报

Aim To examine the therapeutic effects of DHZCP on carbon tetrachloride(CCl4)-induced chemical hepatic fibrosis model in rats and the mechanism of acid-sensitive ion channels 1a(ASIC1a)and vascular endothelial growth factor(VEGF)-related mechanisms.Methods The rats were injected intraperitoneally with CCl4 vegetable oil mixture to establish hepatic fibrosis model,and randomly divided into six groups:control group,hepatic fibrosis model group,DHZCP low dose group,DHZCP medium dose group,DHZCP high dose group and colchicine(Col)positive control group.HE staining was used to observe the pathological changes of hepatic structures in each group,Masson staining to view the production of collagen fibers in each group,and immunohistochemistry,Western blot,q-PCR to investigate the expression level of ASIC1a,CaMKKβ,VEGF,α-SMA,Collagen-I proteins.Results In model group,serum ALT and AST levels were obviously up-regulated,liver tissue structure was severely damaged,and ASIC1a,CaMKKβ,VEGF,α-SMA,Collagen-I gene and protein expression levels were significantly elevated.Compared with model group,each treatment group of DHZCP could markedly alleviate the pathological changes of liver fibrosis caused by CCl4,significantly reduce the serum ALT and AST levels,and dose-dependently down-regulate the gene and protein expression levels of ASIC1a,CaMKKβ,VEGF,α-SMA,Collagen-I,etc.Conclusions DHZCP ameliorates hepatic fibrosis in rats,and its mechanism of action may be associated with the regulation of ASIC1a/VEGF.

Comparative venomic profiles of three spiders of the genus Phoneutria

Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.(AU)

Comparative venomic profiles of three spiders of the genus Phoneutria

Abstract Background: Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.

Targeted ion channel therapy for acute ischemic stroke and cerebral edema / 国际脑血管病杂志

Cerebral edema and its caused elevated intracranial pressure are one of the main causes of death in patients with acute ischemic stroke. The main pathogeneses of brain edema include cytotoxic edema, ionic edema, and angiogenic edema. At present, the treatment strategies used to control brain edema and reduce intracranial pressure are mainly osmotic drugs and hemicraniectomy decompression, which are symptomatic treatments to reduce intracranial pressure. In recent years, it has been proposed to inhibit the ion channel in the formation of brain edema as a therapeutic target, which provides a new direction for the treatment of brain edema.

Locus Coeruleus Acid-Sensing Ion Channels Modulate Sleep–Wakefulness and State Transition from NREM to REM Sleep in the Rat / 神经科学通报·英文版

The locus coeruleus (LC) is one of the essential chemoregulatory and sleep–wake (S–W) modulating centers in the brain. LC neurons remain highly active during wakefulness, and some implicitly become silent during rapid eye movement (REM) sleep. LC neurons are also involved in CO

Research progress of transient receptor potential ion channels and psoriasis / 中国临床药理学与治疗学

The occurrence of psoriasis mainly involves abnormal cellular immune system and the abnormal proliferation and differentiation of keratinocytes. Recent studies have found that transient receptor potential (TRP) ion channels are related to the etiology of psoriasis and play an important role in the pathophysiological process of psoriasis. Using inhibitors or activators of partial TRP channels can improve or alleviate the symptoms of psoriasis, suggesting that partial TRP channels may be new targets for psoriasis treatment. This article mainly reviews the relationship between TRP channels and etiology of psoriasis, and the research advancement of TRP channels as treatment targets for psoriasis.

The electrophysiological remodeling of atrial myocytes of type 1 diabetic mice and effects of AGE / 中国药理学通报

Aim To explore type 1 diabetes mice and the advance glycation end products (AGE) involved in electrical remodeling of atrial myocytes. Methods The diabetic mouse model was induced by intraperitoneal injection of STZ; action potential duration, and the current density of I

Pain-related toxins in scorpion and spider venoms: a face to face with ion channels

Pain is a common symptom induced during envenomation by spiders and scorpions. Toxins isolated from their venom have become essential tools for studying the functioning and physiopathological role of ion channels, as they modulate their activity. In particular, toxins that induce pain relief effects can serve as a molecular basis for the development of future analgesics in humans. This review provides a summary of the different scorpion and spider toxins that directly interact with pain-related ion channels, with inhibitory or stimulatory effects. Some of these toxins were shown to affect pain modalities in different animal models providing information on the role played by these channels in the pain process. The close interaction of certain gating-modifier toxins with membrane phospholipids close to ion channels is examined along with molecular approaches to improve selectivity, affinity or bioavailability in vivo for therapeutic purposes.(AU)

Pain-related toxins in scorpion and spider venoms: a face to face with ion channels

Abstract Pain is a common symptom induced during envenomation by spiders and scorpions. Toxins isolated from their venom have become essential tools for studying the functioning and physiopathological role of ion channels, as they modulate their activity. In particular, toxins that induce pain relief effects can serve as a molecular basis for the development of future analgesics in humans. This review provides a summary of the different scorpion and spider toxins that directly interact with pain-related ion channels, with inhibitory or stimulatory effects. Some of these toxins were shown to affect pain modalities in different animal models providing information on the role played by these channels in the pain process. The close interaction of certain gating-modifier toxins with membrane phospholipids close to ion channels is examined along with molecular approaches to improve selectivity, affinity or bioavailability in vivo for therapeutic purposes.

Neuronas participantes en la modalidad sensorial del dolor bucofacial de la periferia hasta el encéfalo / Neurons involved in the sensory modality of orofacial pain from periphery to encephalon

Introducción: El dolor proveniente de cabeza y cuello se vincula a la vía trigeminal, y participan tres neuronas: neurona de primer orden ubicada en ganglio trigeminal; neurona de segundo orden, en el subnúcleo caudal del nervio trigémino; y la neurona de tercer orden que parte de la zona medial del complejo ventrobasal de tálamo y termina en la corteza cerebral. Objetivo: Interpretar que el daño tisular, mediante impulsos nerviosos es transmitido por una cadena de neuronas hasta el encéfalo. Contenido: Las neuronas de primer orden, sus cuerpos neuronales se encuentran ubicados en el ganglio espinal del trigémino, en hueso temporal. En el subnúcleo caudal, se ubican las neuronas de segundo orden que reciben estímulos nociceptivos y de temperatura de la cara y la boca; sus axones se cruzan en la extensión de este subnúcleo, y ascienden contralateralmente, y establecen sinapsis en el tálamo con neuronas de tercer orden. En el encéfalo no hay un único "centro del dolor", las neuronas de tercer orden, terminan en diferentes áreas de la corteza cerebral que se reconocen como "matriz del dolor". Consideraciones finales: Tres conjuntos de neuronas conforman la vía nociceptiva trigeminal, la primera ubicada en el ganglio trigeminal fuera del sistema nervioso central y los otros dos conjuntos neuronales conforman núcleos dentro del mismo(AU)

Introduction: Pain from the head and neck is linked to the trigeminal pathway and three neurons participate: a first-order neuron located in the trigeminal ganglion, a second-order neuron from the subnucleus caudalis of the trigeminal nerve, and a third-order neuron which starts from the medial area of the ventrobasal thalamus complex and ends in the cerebral cortex. Objective: Describe the way in which a chain of neurons transmit tissue damage to the encephalon by means of nerve impulses. Content: In first-order neurons, their neuronal bodies are located in the trigeminal spinal ganglion, in temporal bone. In the subnucleus caudalis, second-order neurons are found which receive nociceptive and temperature stimuli from the face and mouth. Their axons cross over the extension of this subnucleus, ascend contralaterally and establish synapses with third-order neurons in the thalamus. In the encephalon there is not a single "pain center": third-order neurons end in different areas of the cerebral cortex recognized as the "pain matrix". Final considerations: Three sets of neurons make up the trigeminal nociceptive pathway. The first one is located in the trigeminal ganglion outside the central nervous system whereas the other two form nuclei within it(AU)

El periodo refractario de las células excitables: ¿inconsistencias de un dogma? / The refractory period of excitable cells: Inconsistencies of a dogma?

Resumen Introducción. Los canales activados por voltaje para Na+ y para K+ presentan compuertas de activación e inactivación, las cuales se abren y se cierran dependiendo de la intensidad de la corriente eléctrica que fluye por la membrana cuando está respondiendo a un estímulo. Durante este breve momento, la membrana entra en un periodo de refractariedad que la hace insensible a otros estímulos. Objetivo. Demostrar que los periodos refractarios absoluto y relativo se presentan a medida que se va desarrollando el potencial de acción y no después de que se ha completado, mediante un análisis teórico basado en el funcionamiento eléctrico normal de los canales activados por voltaje para Na+ y K+. Cuestionamientos. En diversos textos y artículos de fisiología, las definiciones de los periodos refractarios absoluto y relativo son confusas y erróneas, puesto que no tienen en cuenta el funcionamiento normal de los canales activados por voltaje. Además, la ubicación que dan a dichos periodos con respecto al potencial de acción es desfasada y su tiempo de duración es incierto. Conclusión. Los periodos refractarios absoluto y relativo se presentan durante el desarrollo del potencial de acción y no después de que ha sido completado.

Abstract Introduction: Voltage-gated Na+ and K+ channels have activation and inactivation gates that open and close depending on the intensity of the electric current flowing through the membrane when it is responding to a stimulus. During this brief moment, the membrane enters a refractory period that makes it insensitive to other stimuli. Objective: To prove that absolute and relative refractory periods occur as the action potential develops rather than after it has been completed, by means of a theoretical analysis based on the normal electrical functioning of voltage-gated Na+ and K+ channels. Questioning: Several texts and articles on physiology provide confusing and misleading definitions of absolute and relative refractory periods, since they don't consider the normal functioning of voltage-gated channels. Furthermore, the location they give to these periods in relation to the action potential is out-of-time and their duration remains uncertain. Conclusion: Absolute and relative refractory periods occur as the action potential develops rather than after it has been completed.

Progress in Research on Mechanosensitive Ion Channel Piezo1/2 in Digestive System Diseases / 胃肠病学

Piezo proteins, including Piezo1, Piezo2, are non-selective mechanosensitive ion channels. They have similar biophysical characteristics, which can transform mechanical signals into biological electric signals. Studies have shown that Piezo proteins play important roles in mechanical-relevant physiological functions and pathophysiological changes of a variety of organs, including gastrointestinal tract. This article reviewed the relationship between Piezo1/2 proteins and digestive system diseases, and discussed the roles of Piezo1/2 under mechanical stress in the development of digestive system diseases, so as to provide a novel target in the study of pathogenesis and treatment of relevant digestive system diseases.

Research advances of mechanically sensitive ion channel Piezo1 in cardiovascular diseases / 中国临床药理学与治疗学

Mechanically sensitive ion channels play an important role in the cells' perception of external pressure and the growth of tissues and organs, and participate in the regulation of various cell functions. Among them, Piezo1 is a non-selective mechanically sensitive ion channel, which mainly exists in endothelial cells and vascular smooth muscle cells. The regulation of vascular function affects the progression of cardiovascular diseases such as atherosclerosis and hypertension. This article mainly reviews the role of Piezo1 in cardiovascular diseases, and provides new directions for the clinical intervention research of cardiovascular diseases.

Acid-sensing ion channels differentially affect ictal-like and non-ictal-like epileptic activities of mouse hippocampal pyramidal neurons in acidotic extracellular pH / 南方医科大学学报

OBJECTIVE@#To investigate the effects of acid-sensing ion channels (ASICs) on electrophysiological epileptic activities of mouse hippocampal pyramidal neurons in the extracellular acidotic condition.@*METHODS@#We investigated effects of extracellular acidosis on epileptic activities induced by elevated extracellular K concentration or the application of an antagonist of GABA receptors in perfusate of mouse hippocampal slices under field potential recordings. We also tested the effects of extracellular acidosis on neuronal excitability under field potential recording and evaluated the changes in epileptic activities of the neurons in response to pharmacological inhibition of ASICs using a specific inhibitor of ASICs.@*RESULTS@#Extracellular acidosis significantly suppressed epileptic activities of the hippocampal neurons by converting ictal-like epileptic activities to non-ictal-like epileptic activities in both high [K ]o and disinhibition models, and also suppressed the intrinsic excitability of the neurons. ASICs inhibitor did not antagonize the inhibitory effect of extracellular acidosis on ictal epileptic activities and intrinsic neuronal excitability, but exacerbated non-ictal epileptic activities of the neurons in extracellular acidotic condition in both high [K]o and disinhibition models.@*CONCLUSIONS@#ASICs can differentially modulate ictal-like and non-ictallike epileptic activities via its direct actions on excitatory neurons.

Advances on GABAergic interneurons in autism spectrum disorders / 浙江大学学报·医学版

More and more evidences support that the abnormality of GABAergic interneurons is associated with autism spectrum disorders (ASD), epilepsy, schizophrenia and other neurodevelopmental disorders. In recent years, numerous drugs have been developed to regulate ion channels and receptors in GABAergic interneurons, including sodium channels and N-methyl-D-aspartate (NMDA) receptors. The activators of Na channel can enhance the action potential of GABAergic interneurons by reducing the inactivation of Na channel. NMDA receptor, as a potential therapeutic target of ASD, can restore the NMDA function of GABAergic interneurons, which would be used to treat behavioral defects. In addition, there are many ion channels and receptors on GABAergic interneurons related to ASD. This article reviews GABAergic interneurons in the pathogenesis of ASD and the related interventions.

Research progress of ion channels relating to cerebral ischemic diseases and prevention and treatment with traditional Chinese medicine / 中国中药杂志

Cerebral ischemia is a series of clinical symptoms and signs of cerebral ischemia, hypoxia and neuronal damage caused by cerebral artery stenosis or occlusion due to atherosclerosis or thrombosis, which seriously affects human health and quality of life. Cerebral ischemia involves the cascade reaction of the "neurovascular unit" system, and finally affects the normal physiological function of nerve cells and produces a series of pathological changes. And the changes in the structure and function of various ion channels in the cell membrane play an important role during this process. This article illustrates the changes in the ion channel associated with ce-rebral ischemic diseases, such as the potassium ion channels, sodium ion channels, calcium channels and other relevant channels, like AQP, TRPM2, TRPM7, TRPV4, ASICs, Cl~- channel, and explores the intervention effect of traditional Chinese medicine in prevention and treatment of cerebral ischemic diseases from the perspective of ion channels, in order to provide references for potential targets involving in drug development for the future prevention and treatment of cerebral ischemic diseases.