Since the discovery of NMDA receptor (NMDAR) dependent long-term potentiation (LTP) in the hippocampus, many studies have demonstrated that NMDAR dependent LTP exists throughout central synapses, ...including those involved in sensory transmission and perception. NMDAR LTP has been reported in spinal cord dorsal horn synapses, anterior cingulate cortex and insular cortex. Behavioral, genetic and pharmacological studies show that inhibiting or reducing NMDAR LTP produced analgesic effects in animal models of chronic pain. Investigation of signalling mechanisms for NMDAR LTP may provide novel targets for future treatment of chronic pain.
Gasdermin E (GSDME) has an important role in inducing secondary necrosis/pyroptosis. Upon apoptotic stimulation, it can be cleaved by activated caspase-3 to generate its N-terminal fragment ...(GSDME-NT), which executes pyroptosis by perforating the plasma membrane. GSDME is expressed in many human lung cancers including A549 cells. Paclitaxel and cisplatin are two representative chemotherapeutic agents for lung cancers, which induce apoptosis via different action mechanisms. However, it remains unclear whether they can induce GSDME-mediated secondary necrosis/pyroptosis in lung A549 cancer cells. Here we showed that both paclitaxel and cisplatin evidently induced apoptosis in A549 cells as revealed by the activation of multiple apoptotic markers. Notably, some of the dying cells displayed characteristic morphology of secondary necrosis/pyroptosis, by blowing large bubbles from the cellular membrane accompanied by caspase-3 activation and GSDME-NT generation. But the ability of cisplatin to induce this phenomenon was much stronger than that of paclitaxel. Consistent with this, cisplatin triggered much higher activation of caspase-3 and generation of GSDME-NT than paclitaxel, suggesting that the levels of secondary necrosis/pyroptosis correlated with the levels of active caspase-3 and GSDME-NT. Supporting this, caspase-3 specific inhibitor (Ac-DEVD-CHO) suppressed cisplatin-induced GSDME-NT generation and concurrently reduced the secondary necrosis/pyroptosis. Besides, GSDME knockdown significantly inhibited cisplatin- but not paclitaxel-induced secondary necrosis/pyroptosis. These results indicated that cisplatin induced higher levels of secondary necrosis/pyroptosis in A549 cells than paclitaxel, suggesting that cisplatin may provide additional advantages in the treatment of lung cancers with high levels of GSDME expression.
Chronic pain is a major health problem and the effective treatment for chronic pain is still lacking. The recent crisis created by the overuse of opioids for pain treatment has clearly shown the need ...for non-addictive novel pain medicine. Conventional pain medicines usually inhibit peripheral nociceptive transmission and reduce central transmission, especially pain-related excitatory transmission. For example, both opioids and gabapentin produce analgesic effects by inhibiting the release of excitatory transmitters and reducing neuronal excitability. Here, we will review recent studies of central synaptic plasticity contributing to central sensitization in chronic pain. Neuronal selective adenylyl cyclase subtype 1 (AC1) is proposed to be a key intracellular protein that causes both presynaptic and postsynaptic forms of long-term potentiation (LTP). Inhibiting the activity of AC1 by selective inhibitor NB001 blocks behavioral sensitization and injury-related anxiety in animal models of chronic pain. We propose that inhibiting injury-related LTPs will provide new mechanisms for designing novel medicines for the treatment of chronic pain and its related emotional disorders.
Ulcerative colitis (UC) is the most common inflammatory bowel disease (IBD); it is incurable, and the treatment is expensive. Trans-anethole (TA), the main component of fennel, exhibits various ...biological activities. An increasing number of studies have demonstrated the efficacy of herbal active ingredients in the treatment of UC. This study aimed to investigate the effect and mechanism of TA in UC. In this study, we have experimented on mice with dextran sulfate sodium salt (DSS)-induced UC. The TA group was gavaged with 62.5 mg/kg TA by gavage once daily on days 8–14. To observe the effect of TA on the colon tissue, various investigations were performed, including western blot and immunohistochemistry for intestinal barrier protein expression, TUNEL staining for apoptosis, western blot, and ELISA for inflammation level, flow cytometry for Th17/Treg, LC–MS for blood bile acid content, GC–MS for blood fatty acid content, and 16s RNA for intestinal contents. TA alleviated weight loss in mice with UC; increased colon length; alleviated intestinal mucosal damage; upregulated claudin-1, occludin, and ZO-1 protein expression levels; reduced inflammatory factors in the colon and serum; and alleviated apoptosis. TA reduced fatty acid and bile acid levels by inhibiting colony abundance and reducing Th17/Treg cell differentiation in the colon. We found that TA alleviates DSS-induced UC by remodeling the intestinal flora to regulate immunity and bile acid metabolism.
Oxytocin is a well-known neurohypophysial hormone that plays an important role in behavioral anxiety and nociception. Two major forms of long-term potentiation, presynaptic LTP (pre-LTP) and ...postsynaptic LTP (post-LTP), have been characterized in the anterior cingulate cortex (ACC). Both pre-LTP and post-LTP contribute to chronic-pain-related anxiety and behavioral sensitization. The roles of oxytocin in the ACC have not been studied. Here, we find that microinjections of oxytocin into the ACC attenuate nociceptive responses and anxiety-like behavioral responses in animals with neuropathic pain. Application of oxytocin selectively blocks the maintenance of pre-LTP but not post-LTP. In addition, oxytocin enhances inhibitory transmission and excites ACC interneurons. Similar results are obtained by using selective optical stimulation of oxytocin-containing projecting terminals in the ACC in animals with neuropathic pain. Our results demonstrate that oxytocin acts on central synapses and reduces chronic-pain-induced anxiety by reducing pre-LTP.
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•Oxytocin microinjected into ACC attenuates injury-related pain and anxiety responses•Oxytocin blocks the maintenance of pre-LTP, but not post-LTP•Oxytocin depolarizes the interneurons and decreases the ratio of E/I transmission•Activation of PVN-ACC pathway blocks pre-LTP and has analgesic and anxiolytic effects
Li et al. report that microinjection of oxytocin into the ACC attenuates nerve-injury-induced nociceptive and anxiety behavioral responses. They show that oxytocin blocks the maintenance of pre-LTP and potentiates inhibitory transmission. Optical activation of endogenous oxytocin release in the ACC blocks pre-LTP and produces analgesic and anxiolytic effects.
The burden of kidney, bladder, and prostate cancers has changed in recent decades. This study aims to investigate the global and regional burden of, and attributable risk factors for genitourinary ...cancers during the past 30 years.
We extracted data of kidney, bladder, and prostate cancers from the Global Burden of Disease 2019 database, including incidence, mortality, disability-adjusted life-years (DALYs), and attributable risk factors from 1990 to 2019. Estimated annual percentage changes (EAPC) were calculated to assess the changes in age-standardized incidence rate, age-standardized mortality rate (ASMR), and age-standardized DALYs rate (ASDR). The associations between cancers burden and socio-demographic index (SDI) were also analyzed.
Compared with 1990, the global incident cases in 2019 were higher by 154.78%, 123.34%, and 169.11% for kidney, bladder, and prostate cancers, respectively. During the 30-year study period, there was a downward trend in ASMR and ASDR for bladder cancer (EAPC = - 0.68 and - 0.83, respectively) and prostate cancer (EAPC = - 0.75 and - 0.71, respectively), but an upward trend for kidney cancer (EAPC = 0.35 and 0.12, respectively). Regions and countries with higher SDI had higher incidence, mortality, and DALYs for all three types of cancers. The burden of bladder and prostate cancers was mainly distributed among older men, whereas the burden of kidney cancer increased among middle-aged men. Smoking related mortality and DALYs decreased, but high body mass index (BMI) and high fasting plasma glucose (FPG) related mortality and DALYs increased among kidney, bladder, and prostate cancers during the study period.
Kidney, bladder, and prostate cancers remain major global public health challenges, but with distinct trend for different disease entity across different regions and socioeconomic status. More proactive intervention strategies, at both the administrative and academic levels, based on the dynamic changes, are needed.
HOX (X=Cl, Br, I, and At) can engage in either a H‐bond (HB) or halogen bond (XB) with a base‐like HCN, NH3, and imidazole. Although the former is energetically preferred for X=Cl and Br, it is the ...XB that is more stable for At, with I showing little preference. MgY2 forms a Mg‐bond with the O atom of HOX, which grows stronger in the order X=Cl<Br<I<At and Y=F<Cl<Br. When all three molecules are combined, both the Mg and the H/X bonds are cooperatively strengthened to a large degree. Rather than causing a reversal in the HB/XB competition, the Mg‐bond acts primarily to amplify the natural preference within the dimer. The Mg‐bond induces a certain degree of transfer from O to N of the bridging atom in the H/X bond. Comparison is also made with the effects of a Be‐bond.
The H/X files: The function of HOX as simultaneous electron donor and acceptor in MgY2⋅⋅⋅HOX⋅⋅⋅base results in positive cooperativity and a surprising strengthening of both bonds. The relative stabilities of the HB and XB in the dimers are amplified within the context of the triads. The addition of the MgB causes at least a partial migration of the bridging H/X within the respective HB/XB. In some cases, this motion is large enough that it can be characterized as a proton or halogen transfer.
Cortical areas including the anterior cingulate cortex (ACC) play critical roles in different types of chronic pain. Most of previous studies focus on the sensory inputs from somatic areas, and less ...information about plastic changes in the cortex for visceral pain. In this study, chronic visceral pain animal model was established by injection with zymosan into the colon of adult male C57/BL6 mice. Whole cell patch‐clamp recording, behavioral tests, western blot, and Cannulation and ACC microinjection were employed to explore the role of adenylyl cyclase 1 (AC1) in the ACC of C57/BL6 and AC1 knock out mice. Integrative approaches were used to investigate possible changes of neuronal AC1 in the ACC after the injury. We found that AC1, a key enzyme for pain‐related cortical plasticity, was significantly increased in the ACC in an animal model of irritable bowel syndrome. Inhibiting AC1 activity by a selective AC1 inhibitor NB001 significantly reduced the up‐regulation of AC1 protein in the ACC. Furthermore, we found that AC1 is required for NMDA GluN2B receptor up‐regulation and increases of NMDA receptor‐mediated currents. These results suggest that AC1 may form a positive regulation in the cortex during chronic visceral pain. Our findings demonstrate that the up‐regulation of AC1 protein in the cortex may underlie the pathology of chronic visceral pain; and inhibiting AC1 activity may be beneficial for the treatment of visceral pain.
Anterior cingulate cortex (ACC) plays critical roles in different types of chronic pain. Calcium‐stimulated, neuronal selective adenylyl cyclase subtype 1 (AC1) is critical for injury‐triggered cortical plasticity and chronic pain. We demonstrate that AC1 protein was up‐regulated in the ACC for a long‐period of time in a mouse model of chronic visceral pain. AC1 activity is required for the up‐regulation of AC1 protein, suggesting that AC1 may form a positive feedback in the cortex during chronic visceral pain. This is the first time to demonstrate that AC1 protein can undergo long‐term increases in central neurons after peripheral injuries.
Previous studies have demonstrated that brain-derived neurotrophic factor (BDNF) is one of the diffusible messengers for enhancing synaptic transmission in the hippocampus. Less information is ...available about the possible roles of BDNF in the anterior cingulate cortex (ACC). In the present study, we used 64-electrode array field recording system to investigate the effect of BDNF on ACC excitatory transmission. We found that BDNF enhanced synaptic responses in a dose-dependent manner in the ACC in C57/BL6 mice. The enhancement was long-lasting, and persisted for at least 3 h. In addition to the enhancement, BDNF also recruited inactive synaptic responses in the ACC. Bath application of the tropomyosin receptor kinase B (TrkB) receptor antagonist K252a blocked BDNF-induced enhancement. L-type voltage-gated calcium channels (L-VGCC), metabotropic glutamate receptors (mGluRs), but not NMDA receptors were required for BDNF-produced enhancement. Moreover, calcium-stimulated adenylyl cyclase subtype 1 (AC1) but not AC8 was essential for the enhancement. A selective AC1 inhibitor NB001 completely blocked the enhancement. Furthermore, BDNF-produced enhancement occluded theta burst stimulation (TBS) induced long-term potentiation (LTP), suggesting that they may share similar signaling mechanisms. Finally, the expression of BDNF-induced enhancement depends on postsynaptic incorporation of calcium-permeable AMPA receptors (CP-AMPARs) and protein kinase Mζ (PKMζ). Our results demonstrate that cortical BDNF may contribute to synaptic potentiation in the ACC.
Human brain microvascular endothelial cells (HBMVECs) and microglia play critical roles in regulating cerebral homeostasis during ischemic stroke. However, the role of HBMVECs‐derived exosomes in ...microglia polarization after stroke remains unknown. We isolated exosomes (Exos) from oxygen glucose deprivation (OGD)‐exposed HBMVECs, before added them into microglia. Microglia polarization markers were tested using RT‐qPCR or flow cytometry. Inflammatory cytokines were measured with ELISA. Endothelial cell damage was assessed by cell viability, apoptosis, apoptosis‐related proteins, oxidative stress, and angiogenic activity using CCK‐8, flow cytometry, western blot, ELISA, and endothelial tube formation assay, respectively. We also established middle cerebral artery occlusion (MCAO) mice model to examine the function of circ_0000495 on stroke in vivo. Our study found that HBMVECs‐Exos reduced M2 markers (IL‐10, CD163, and CD206), increased M1 markers (TNF‐α, IL‐1β, and IL‐12), CD86‐positive cells, and inflammatory cytokines (TNF‐α and IL‐1β), indicating the promotion of microglial M1‐polarization. Microglial M1‐polarization induced by HBMVECs‐Exos reduced viability and promoted apoptosis and oxidative stress, revealing the aggravation of endothelial cell damage. However, circ_0000495 silencing inhibited HBMVECs‐Exos‐induced alterations. Mechanistically, circ_0000495 adsorbed miR‐579‐3p to upregulate toll‐like receptor 4 (TLR4) in microglia; miR‐579‐3p suppressed HBMVECs‐Exos‐induced alterations via declining TLR4; furthermore, Yin Yang 1 (YY1) transcriptionally activated circ_0000495 in HBMVECs. Importantly, circ_0000495 aggravated ischemic brain injury in vivo via activating TLR4/nuclear factor‐κB (NF‐κB) pathway. Collectively, OGD‐treated HBMVECs‐Exos transmitted circ_0000495 to regulate miR‐579‐3p/TLR4/NF‐κB axis in microglia, thereby facilitating microglial M1‐polarization and endothelial cell damage.
In OGD‐subjected BMVECs, the upregulated YY1 transcriptionally activated circ_0000495, then circ_0000495 was transported by exosomes to microglial cells. In microglial cells, circ_0000495 targeted miR‐579‐3p to upregulate TLR4, leading to M1 microglial polarization, which in turn promoted apoptosis and inhibited angiogenesis of BMVECs.
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