A standardized extract of Centella asiatica (ECa 233) prevents temporomandibular joint osteoarthritis by modulating the expression of local inflammatory mediators in mice

Abstract Objectives To investigate the effect of a standardized extract of Centella asiatica (ECa 233), which has anti-inflammatory properties, on the local expression of the transient receptor potential vanilloid 1 (TRPV1), the acid-sensing ion channel subunit 3 (ASIC3), and the calcitonin gene-related peptide (CGRP) in the temporomandibular joint (TMJ) structure 21 days after injecting the TMJ with complete Freund's adjuvant (CFA). Methodology A mouse model was induced by analyzing the CFA-injected TMJ on days 7, 14, and 21. We assessed TMJ histology by the osteoarthritis cartilage grade score. Then, we observed the effect of different ECa 233 concentrations (30, 100, and 300 mg/kg) and of 140 mg/kg ibuprofen doses on TRPV1, ASIC3, and CGRP local expression on day 21. Results Osteoarthritis cartilage scores were 1.17±0.37 and 3.83±0.68 on days 14 and 21, respectively, in the CFA group (n=5). On day 21, TRPV1, ASIC3, and CGRP expression significantly increased in the CFA group. In the ibuprofen-treated group, TRPV1 expression significantly decreased, but ASIC3 and CGRP showed no significant difference. All ECa 233 doses reduced TRPV1 expression, but the 100 mg/kg ECa 233 dose significantly decreased ASIC3 expression. Conclusions TRPV1, ASIC3, and CGRP expression increased in mice with TMJ-OA on day 21. All ECa 233 and ibuprofen doses inhibited pathogenesis by modulating the local expression of TRPV1 and ASIC3. Therefore, ECa 233 was more effective than ibuprofen.

Postsynaptic Targeting and Mobility of Membrane Surface-Localized hASIC1a / 神经科学通报·英文版

Acid-sensing ion channels (ASICs), the main H

ASIC1a contributes to the symptom of pain in a rat model of chronic prostatitis / 亚洲男科学杂志(英文版)

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.

Expression of acid-sensing ion channel 1a in the central nervous system of mice with panic-like behavior / 中华行为医学与脑科学杂志

Objective To explore the expression of acid-sensing ion channel 1a ( ASIC1a) in cen-tral nervous system of mice with panic like behavior. Methods 20 male C57BL/6 mice were randomly di-vided into two groups according to their weight( 10 mice in each group):the group experienced rat exposure test of panic-like behavior model ( RET group ) and the control group ( Ctr group ) . A panic-like behavior model was established by rat exposure stimuli. Ten minutes defensive and avoidance behaviors of mice were recorded with a horizontal video camera. The anxiety level of mice was evaluated by elevated plus maze ( EPM) test.Western blot was used to detect the ASIC 1a expression in different brain areas of prefrontal cor-tex,hippocampus and periaqueductal gray (PAG). Results Compared with Ctr group,mice in RET group spent significantly more time in freezing ((5.83±1.92)s) than that of Ctr group ((1.00±0.45)s) (P<0.01),had significantly higher frequency of risk assessment behavior (5.33±0.49) than that of Ctr group (0.60±0.40) (P<0.01),spent significantly less time to contact the wire mesh ((17.83±4.38)s) than that of Ctr group((50.00±6.90)s) (P<0.01),and significantly more time of staying in the protected area((431.00±33.13)s) than that of Ctr group((264.40±40.43)s) (P<0.01).At the same time,RET group showed sig-nificantly lower time percent ((8.28±1.12)％) than Ctr group ((16.81±2.13)％) in opened arm (P<0.05) and significantly higher time percent ((80.08±4.26)％) than Ctr group ((60.91±5.27)％) in the closed arm (P<0.05).Western blot suggested that the expression level of ASIC 1a in the prefrontal cortex (1.32± 0.05) and hippocampus (2.56±0.30) significantly increased than that of Ctr group((0.98±0.07),(1.56± 0.16)( P<0.05),while significantly decreased in the PAG (0.83± 0.02) than that of Ctr group(1.26±0.05) ( P<0.05) . Conclusion Rat exposure stimuli can induce panic-like behavior among mice,which increases the expression of ASIC 1a in the prefrontal cortex and hippocampus,but decreases the level of ASIC 1a in the PAG.

ASIC1a contributes to the symptom of pain in a rat model of chronic prostatitis / 亚洲男科学杂志(英文版)

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.

The fate of medications evaluated for ischemic stroke pharmacotherapy over the period 1995-2015

Stroke is a brain damage caused by a loss of blood supply to a portion of the brain, which requires prompt and effective treatment. The current pharmacotherapy for ischemic stroke primarily relies on thrombolysis using recombinant tissue plasminogen activators (rt-PAs) to breakdown blood clots. Neuroprotective agents that inhibit excitatory neurotransmitters are also used to treat ischemic stroke but have failed to translate into clinical benefits. This poses a major challenge in biomedical research to understand what causes the progressive brain cell death after stroke and how to develop an effective pharmacotherapy for stroke. This brief review analyzes the fate of about 430 potentially useful stroke medications over the period 1995-2015 and describes in detail those that successfully reached the market. Hopefully, the information from this analysis will shed light on how future stroke research can improve stroke drug discovery.

Expression of Pain Receptors by Arthritis Treatment in Collagen Induced Murine Model of Rheumatoid Arthritis

OBJECTIVE: Rheumatoid arthritis, the most common form of arthritis, is typically characterized by induced inflammatory pain in joints. Recent studies have reported on the expression of pain receptors such as transient receptor potential vanilloid 1 (TRPV1) and acid sensing ion channel 3 (ASIC3), which are related to pain induction and regulation. This study was conducted to investigate the expression of TRPV1 and ASIC3 in response to the analgesic effect of an arthritis treatment in a collagen-induced arthritis (CIA). METHODS: Mice were divided into 3 groups: Control, CIA, and CIA with arthritis treatment. Mice received intraperitoneal injection with 10 mg/kg infliximab and 10 mg/kg meloxicam five times per week for 3 weeks. Mechanical hyperalgesia, histologic examination of the feet, serum levels of inflammatory cytokine such as interleukin-6 (IL-6), and interleukin-17 (IL-17), TRPV1 and ASIC3 expression were investigated. RESULTS: The serum levels of IL-6 and IL-17 were lower in the treatment group (73.77+/-10.11 pg/mL and 26.75+/-7.17 pg/mL, respectively) compared to the CIA group (p<0.001). Histological analysis showed decreased synovial cell proliferation, leukocyte infiltration, and cartilage destruction in the treatment group compared with the CIA group. The CIA group that underwent arthritis treatment showed a significantly increased withdrawal threshold of mechanical nociception on the hind paw and increased expression of TRPV1 and ASIC3 compared to the CIA group. CONCLUSION: Arthritis treatment resulted in an anti-inflammatory and analgesic effect through upregulation of the activity of TRPV1 and ASIC3 in CIA mice.

Survival analysis of ASIC3 -/-and TRPV1 -/-mice / 中国比较医学杂志

Objective To analyze the survival curves of ASIC3 -/-and TRPV1 -/-mice, and provide a reference for further breeding of these strains of mice.Methods Forty-four ASIC3 -/-mice and sixty-one TRPV1 -/-mice were included in this study.The survival of the mice was observed in normal feeding for 500 days, survival curves were drawn, and their survival was analyzed.Results With the passing of time, the survival probability was decreased in ASIC3 -/-mice and TRPV1 -/-mice.The survival probability of TRPV1 -/-mice was significantly better than that of ASIC3 -/-mice (P =0.004, P <0.01).No significant difference was observed between the males and females of the same strain. Conclusions The survival probability of TRPV1 -/-mice is better than that of ASIC3 -/-mice.There is no significant gender difference in the two strains of mice.

Neuroprotective effect of sophocarpine against transient focal cerebral ischemia via down-regulation of the acid-sensing ion channel 1 in rats / 国际脑血管病杂志

Objective To investigate the neuroprotective effect of sophocarpine against transient focal cerebral ischemia via down-regulation of the acid-sensing ion channel 1(ASICl) in rats.Methods Twenty-five SD rats were randomly allocated into sham operation,cerebral ischemia/reperfusion,and 5,10,and 20 mg/kg sophocarpine pretreatment groups (n=5 in each group).A rat focal ischemia model was induced by the intraluminal suture method.Five,10 and 20 mg/kg sophocarpine were injected intraperitoneally for pretreatrnent.2,3,5-triphenyltetrazolium chloride staining was used to detect cerebral infarct volume.TUNEL staining was used to detect apoptosis.Immunohistochemistry and Western blot were used to detect the expression of ASIC1 and ASIC2.Results The infarct volume after ischemia-reperfusion was(181.21±9.21)mm3,while the 5,10,and 20 mg/kg sophocarpine pretreatment groups were(150.12±6.19),(52.31±4.20),and(32.18±3.82)mm3,respectively;the neurological function scores in the cerebral ischemia/reperfusion group was(3.62±0.36),while the 5,10,and 20 mg/kg sophocarpine pretreatment grows were(3.15±0.36),(1.92±0.18),and(1.85±0.21),respectively;The surviving neurons only accounted for(31.2±2.8)% of the total cell number in the cerebral ischemia-reperfusion group,while they accounted for(51.2±3.7)%,(76.5±2.1)%,and(77.1±4.1)% in the 5,10,and 20 mg/kg sophocarpine pretreatnmat groups.Compared with the cerebral ischemia/reperfusion group,the cerebral infarct volume was decreased significantly in the sophocarpine pretreatrnent groups(all P<0.01),the neurological function scores were decreased significantly(all P<0.01),and the number of apoptotic cells was decreased significantly (all P<0.01).Immunohistochemistry showed that the number of ASIC-1 positive cells in the sham operation,cerebral ischemia-reperfusion,and 5,10,and 20 mg/kg sophocarpine pretreatment groups were(162.5±8.3),(165.1±5.3),(138.3±7.2),(82.1±6.3),and(69.2±5.5)/mm respectively;Western blot showed that the ASIC1 protein expression was decreased sigaificantly in the 10 and 20 mg/ky sophocarpine pretreatment groups (P<0.01),while there WaS no significant difference in the ASIC2 protein expression.Condusions Sophocarpine may play a neuroprotective role for cerebral ischemia-reperfusion injury in rats via down-regulating the expression of ASIC1 protein.

El plomo inhibe la corriente activada por protones (ASIC) en las neuronas de los ganglios dorsales / Lead inhibits proton gated currents (ASIC) in dorsal root ganglion neurons

Antecedentes. Los canales iónicos ASIC (del inglés Acid Sensing Ion Channel) son canales iónicos activados por reducciones transitorias en el pH extracelular. Pese a no conocerse con exactitud su mecanismo, la activación ocurre por medio de la unión de protones al dominio extracelular del canal y es modulada por iones calcio y zinc. Objetivo. El hecho de que los cationes divalentes modifiquen el funcionamiento del canal nos llevó a preguntar si el plomo, otro catión divalente, sería capaz de alterar el funcionamiento de los ASIC. Métodos y resultados. Mediante el uso de la técnica de fijación de voltaje en configuración de célula completa en las neuronas de los ganglios de la raíz dorsal de la rata, encontramos que el plomo inhibe la corriente ASIC en forma dependiente de la concentración. Conclusiones. Estos resultados contribuyen a definir los mecanismos de activación de los canales ASIC y a explicar algunos de los mecanismos tóxicos del plomo en el organismo.

BACKGROUND: Acid sensing ion channels (ASIC) are ionic channels activated by transient pH reductions in the ext raceilularenvi ronment. Although the activation mechanism is not fully elucidated, it is clear that the channel is activated by proton binding to its extraceilular domain, a process that is modulated by calcium and zinc. OBJECTIVE: The fact that divalent cations are able to modify ASIC operation, lead us to consider if lead, anotherdivalent cation and widely distributed neurotoxicant, is also capable to affect ASIC function. METHODS: For this purpose, we recordedASiC currents in rat dorsal root ganglion neurons using the whole cell patch-clamp technique. RESULTS: The results indicated that lead inhibits ASIC currents in a concentration -dependent fashion. CONCLUSIONS: These results contribute to the understanding of the activation mechanism of ASIC and to explain some of the toxic mechanisms of lead in the organism.

Biological Characteristics of Acid Sensing Ion Channels (ASICs) and Their Modulations / 生物化学与生物物理进展

ASICs are H+-gated novel cation ion channels, which belong to the epithelial sodium channels (NaC/DEG) superfamily. As recent studies focus, ASICs are expected to be pharmacological targets on protecting the neuron from ischemia and damage, improving the ability of memory and study, curing epilepsy and analgesia. It is not until the most recentness that the subunits of ASICs have been cloned. Now, researchers have paid more attention to the distribution, expression, function and modulation of ASICs in the organism.