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Cancer Research Dec 2021The capacity of targeted anticancer agents to exert immunomodulatory effects provides a strong rationale to develop novel agents suitable for combinatorial regimens with...
The capacity of targeted anticancer agents to exert immunomodulatory effects provides a strong rationale to develop novel agents suitable for combinatorial regimens with immunotherapy to improve clinical outcomes. In this study, we developed a dual-targeting PI3K and HDAC inhibitor BEBT-908 that potently inhibits tumor cell growth and potentiates anti-PD1 therapy in mice by inducing immunogenic ferroptosis in cancer cells. Treatment with BEBT-908 promoted ferroptotic cell death of cancer cells by hyperacetylating p53 and facilitating the expression of ferroptotic signaling. Furthermore, BEBT-908 promoted a proinflammatory tumor microenvironment that activated host antitumor immune responses and potentiated immune checkpoint blockade therapy. Mechanistically, BEBT-908-induced ferroptosis led to upregulation of MHC class I and activation of endogenous IFNγ signaling in cancer cells via the STAT1 signaling pathway. The dual PI3K/HDAC inhibitor BEBT-908 is a promising targeted therapeutic agent against multiple cancer types that promotes immunogenic ferroptosis and enhances the efficacy of immunotherapy. SIGNIFICANCE: The dual PI3K/HDAC inhibitor BEBT-908 elicits potent antitumor responses, effectively inducing immunogenic ferroptosis of tumor cells and potentiating cancer immunotherapy.
Topics: Animals; Apoptosis; Cell Proliferation; Colonic Neoplasms; Ferroptosis; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Male; Mice; Mice, Inbred C57BL; Mice, Inbred NOD; Mice, SCID; Phosphoinositide-3 Kinase Inhibitors; Pyrimidines; Tumor Cells, Cultured; Xenograft Model Antitumor Assays
PubMed: 34711611
DOI: 10.1158/0008-5472.CAN-21-1547 -
Advances in Pharmacology (San Diego,... 2019Conventional antidepressants (biogenic amine mechanisms) are not fully efficacious (e.g., symptoms remain after treatment, not all patients respond), produce effects... (Review)
Review
Conventional antidepressants (biogenic amine mechanisms) are not fully efficacious (e.g., symptoms remain after treatment, not all patients respond), produce effects only after weeks of daily dosing, and do not impact all disease symptoms. In contrast, a new class of antidepressants has been emerging since 2006 that has demonstrated rapid onset, large effect size, activity after only a single or few dose applications, and positive impact in treatment refractory patients and against some treatment-resistant symptoms (e.g., anhedonia). Rapid-acting antidepressant drug action has been demonstrated in controlled clinical studies for ketamine, a few other NMDA receptor antagonists, and scopolamine. Less clinical data are currently available for psychedelic drugs such as psilocybin, lysergic acid diethylamide, and ayahuasca. The mechanisms of action of rapid-acting antidepressants are not fully understood. However, a general triggering mechanism appears to involve the potentiation of AMPA receptor function. Although the durability of antidepressant effects of ketamine and scopolamine is limited, psychedelic drugs have been reported to produce effects for many months. The primary impediment to generating a medicine of this type for depressed patients is side effects and the lack of methods to ensure enduring antidepressant effects. Thus, further exploration of drug possibilities continues. Esketamine ((S)-ketamine) was recently FDA approved. Compounds currently in clinical development include the NMDA receptor antagonist (R)-ketamine, the NMDA receptor modulator, GLYX-13 (Rapastinel), and the AMPA receptor potentiator TAK-653. Additional pharmacological classes have produced effects in the preclinical laboratory to suggest their potential as rapid-acting agents. These include mGlu2/3 receptor antagonists, AMPA receptor potentiators, and negative allosteric modulators of GABA(α5) receptors. In all cases, molecules exist that could be used to provide clinical proof of concept testing.
Topics: Animals; Antidepressive Agents; Drug Evaluation, Preclinical; Hallucinogens; Humans; Muscarinic Antagonists; Receptors, Muscarinic; Receptors, N-Methyl-D-Aspartate
PubMed: 31378256
DOI: 10.1016/bs.apha.2019.03.002 -
Experimental Brain Research Aug 2020Quadripulse stimulation (QPS) is a newly developed stimulation method to induce neural plasticity in humans. One stimulation burst consisting of four monophasic pulses... (Review)
Review
Quadripulse stimulation (QPS) is a newly developed stimulation method to induce neural plasticity in humans. One stimulation burst consisting of four monophasic pulses is given every 5 s for 30 min. A total of 360 bursts (1440 pulses) are given in one session. Short-interval QPS potentiates the target cortical excitability and long-interval QPS depresses it. QPS at an inter-pulse interval of 5 ms (QPS5) induces long-term potentiation (LTP)-like effects most efficiently and QPS50 induces long-term depression (LTD)-like effects most effectively in the primary motor cortex. In this mini-review, we briefly introduce QPS: (i) principle and cortical plasticity (stimulators and protocols, synaptic plasticity, underlying mechanisms, meta-plasticity, axonal plasticity, and drug effects), (ii) robust and strong neural plasticity induction (variability, influence of phasic muscle contraction, independency of BDNF polymorphism, sensory cortical plasticity, neural plasticity in the contralateral hemisphere, on-line effects on the brain networks, studies of normal brain physiology, and visuomotor sequence learning), (iii) therapeutic applications to neurological and psychiatric disorders (Parkinson's disease, epilepsy, cerebrovascular disease, and major depression), (iv) safety, and (v) future issues. Based on this evidence, we propose that QPS is currently the most powerful and reliable non-invasive brain stimulation method to induce neural plasticity in humans.
Topics: Evoked Potentials, Motor; Humans; Long-Term Potentiation; Motor Cortex; Neuronal Plasticity; Transcranial Magnetic Stimulation
PubMed: 32211927
DOI: 10.1007/s00221-020-05788-w -
PLoS Pathogens Aug 2023Fungal infections are rising, with over 1.5 billion cases and more than 1 million deaths recorded each year. Among these, Candida infections are frequent in at-risk...
Fungal infections are rising, with over 1.5 billion cases and more than 1 million deaths recorded each year. Among these, Candida infections are frequent in at-risk populations and the rapid development of drug resistance and tolerance contributes to their clinical persistence. Few antifungal drugs are available, and their efficacy is declining due to the environmental overuse and the expansion of multidrug-resistant species. One way to prolong their utility is by applying them in combination therapy. Here, we highlight recently described azole potentiators belonging to different categories: natural, repurposed, or novel compounds. We showcase examples of molecules and discuss their identified or proposed mode of action. We also emphasise the challenges in azole potentiator development, compounded by the lack of animal testing, the overreliance on Candida albicans and Candida auris, as well as the limited understanding of compound efficacy.
Topics: Animals; Candida; Candida albicans; Candidiasis; Antifungal Agents; Azoles
PubMed: 37651385
DOI: 10.1371/journal.ppat.1011583 -
Expert Opinion on Biological Therapy Jul 2018Cystic fibrosis (CF) is a multisystem illness caused by abnormalities in the CF transmembrane conductance regulator (CFTR) gene and protein. CFTR is an ion channel... (Review)
Review
INTRODUCTION
Cystic fibrosis (CF) is a multisystem illness caused by abnormalities in the CF transmembrane conductance regulator (CFTR) gene and protein. CFTR is an ion channel regulating transport of chloride, bicarbonate, and water, and influencing sodium resorption. It is inherited as an autosomal recessive disorder, and with about 70,000 CF patients worldwide, it is the most common life shortening disease among persons of European descent. CFTR disease-causing mutations have been organized into six classes. :
AREAS COVERED
Recently, small molecule targeted therapy for specific classes of CFTR abnormalities have included CFTR correctors that decrease protein degradation and CFTR potentiators that increase channel open probability enhancing chloride transport.
EXPERT OPINION
Although there are many novel medications in preclinical and clinical testing, there is need for safe and effective CFTR modulating drugs and immunomodulatory medications to decrease the abundant neutrophilic inflammation response in the airway without unwanted adverse effects. Thymosin alpha 1 treatment of airway cells isolated from phe508del CF patients and from CF knockout mice, decreased inflammation, increased CFTR maturation, and facilitated translocation of CFTR protein to the plasma membrane increasing channel activity. If similar results are seen in humans with CF, thymosin alpha 1 has the unique potential to be a single molecule therapy for treating CF airway disease.
Topics: Animals; Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator; Drug Discovery; Health Services Needs and Demand; Humans; Inflammation; Mice; Mice, Knockout; Mutation; Thymalfasin
PubMed: 30063865
DOI: 10.1080/14712598.2018.1484101 -
Nature Communications Aug 2023γ-Aminobutyric acid type A (GABA) receptors mediate fast inhibitory signaling in the brain and are targets of numerous drugs and endogenous neurosteroids. A subset of...
γ-Aminobutyric acid type A (GABA) receptors mediate fast inhibitory signaling in the brain and are targets of numerous drugs and endogenous neurosteroids. A subset of neurosteroids are GABA receptor positive allosteric modulators; one of these, allopregnanolone, is the only drug approved specifically for treating postpartum depression. There is a consensus emerging from structural, physiological and photolabeling studies as to where positive modulators bind, but how they potentiate GABA activation remains unclear. Other neurosteroids are negative modulators of GABA receptors, but their binding sites remain debated. Here we present structures of a synaptic GABA receptor bound to allopregnanolone and two inhibitory sulfated neurosteroids. Allopregnanolone binds at the receptor-bilayer interface, in the consensus potentiator site. In contrast, inhibitory neurosteroids bind in the pore. MD simulations and electrophysiology support a mechanism by which allopregnanolone potentiates channel activity and suggest the dominant mechanism for sulfated neurosteroid inhibition is through pore block.
Topics: Female; Humans; Neurosteroids; Pregnanolone; Receptors, GABA-A; Binding Sites; Sulfates; gamma-Aminobutyric Acid
PubMed: 37607940
DOI: 10.1038/s41467-023-40800-1 -
Acta Pharmaceutica Sinica. B Aug 2023Vincristine, a widely used chemotherapeutic agent for treating different cancer, often induces severe peripheral neuropathic pain. A common symptom of...
Vincristine, a widely used chemotherapeutic agent for treating different cancer, often induces severe peripheral neuropathic pain. A common symptom of vincristine-induced peripheral neuropathic pain is mechanical allodynia and hyperalgesia. However, mechanisms underlying vincristine-induced mechanical allodynia and hyperalgesia are not well understood. In the present study, we show with behavioral assessment in rats that vincristine induces mechanical allodynia and hyperalgesia in a PIEZO2 channel-dependent manner since gene knockdown or pharmacological inhibition of PIEZO2 channels alleviates vincristine-induced mechanical hypersensitivity. Electrophysiological results show that vincristine potentiates PIEZO2 rapidly adapting (RA) mechanically-activated (MA) currents in rat dorsal root ganglion (DRG) neurons. We have found that vincristine-induced potentiation of PIEZO2 MA currents is due to the enhancement of static plasma membrane tension (SPMT) of these cells following vincristine treatment. Reducing SPMT of DRG neurons by cytochalasin D (CD), a disruptor of the actin filament, abolishes vincristine-induced potentiation of PIEZO2 MA currents, and suppresses vincristine-induced mechanical hypersensitivity in rats. Collectively, enhancing SPMT and subsequently potentiating PIEZO2 MA currents in primary afferent neurons may be an underlying mechanism responsible for vincristine-induced mechanical allodynia and hyperalgesia in rats. Targeting to inhibit PIEZO2 channels may be an effective analgesic method to attenuate vincristine-induced mechanical hypersensitivity.
PubMed: 37655331
DOI: 10.1016/j.apsb.2023.05.010 -
Current Opinion in Neurobiology Jun 2017It is well documented that sleep contributes to memory consolidation and it is also accepted that long-term synaptic plasticity plays a critical role in memory... (Review)
Review
It is well documented that sleep contributes to memory consolidation and it is also accepted that long-term synaptic plasticity plays a critical role in memory formation. The mechanisms of this sleep-dependent memory formation are unclear. Two main hypotheses are proposed. According to the first one, synapses are potentiated during wake; and during sleep they are scaled back to become available for the learning tasks in the next day. The other hypothesis is that sleep slow oscillations potentiate synapses that were depressed due to persistent activities during the previous day and that potentiation provides physiological basis for memory consolidation. The objective of this review is to group information on whether cortical synapses are up-scaled or down-scaled during sleep. We conclude that the majority of cortical synapses are up-regulated by sleep slow oscillation.
Topics: Humans; Memory; Neuronal Plasticity; Sleep; Synapses
PubMed: 28453998
DOI: 10.1016/j.conb.2017.03.019 -
BioRxiv : the Preprint Server For... Mar 2024The cystic fibrosis transmembrane conductance regulator (CFTR) is a crucial ion channel whose loss of function leads to cystic fibrosis, while its hyperactivation leads...
The cystic fibrosis transmembrane conductance regulator (CFTR) is a crucial ion channel whose loss of function leads to cystic fibrosis, while its hyperactivation leads to secretory diarrhea. Small molecules that improve CFTR folding (correctors) or function (potentiators) are clinically available. However, the only potentiator, ivacaftor, has suboptimal pharmacokinetics and inhibitors have yet to be clinically developed. Here we combine molecular docking, electrophysiology, cryo-EM, and medicinal chemistry to identify novel CFTR modulators. We docked ~155 million molecules into the potentiator site on CFTR, synthesized 53 test ligands, and used structure-based optimization to identify candidate modulators. This approach uncovered novel mid-nanomolar potentiators as well as inhibitors that bind to the same allosteric site. These molecules represent potential leads for the development of more effective drugs for cystic fibrosis and secretory diarrhea, demonstrating the feasibility of large-scale docking for ion channel drug discovery.
PubMed: 37745391
DOI: 10.1101/2023.09.09.557002 -
Cell Reports Oct 2023The amygdala, cholinergic basal forebrain, and higher-order auditory cortex (HO-AC) regulate brain-wide plasticity underlying auditory threat learning. Here, we perform...
The amygdala, cholinergic basal forebrain, and higher-order auditory cortex (HO-AC) regulate brain-wide plasticity underlying auditory threat learning. Here, we perform multi-regional extracellular recordings and optical measurements of acetylcholine (ACh) release to characterize the development of discriminative plasticity within and between these brain regions as mice acquire and recall auditory threat memories. Spiking responses are potentiated for sounds paired with shock (CS+) in the lateral amygdala (LA) and optogenetically identified corticoamygdalar projection neurons, although not in neighboring HO-AC units. Spike- or optogenetically triggered local field potentials reveal enhanced corticofugal-but not corticopetal-functional coupling between HO-AC and LA during threat memory recall that is correlated with pupil-indexed memory strength. We also note robust sound-evoked ACh release that rapidly potentiates for the CS+ in LA but habituates across sessions in HO-AC. These findings highlight a distributed and cooperative plasticity in LA inputs as mice learn to reappraise neutral stimuli as possible threats.
Topics: Mice; Animals; Acoustic Stimulation; Learning; Basolateral Nuclear Complex; Amygdala; Acetylcholine; Cholinergic Agents
PubMed: 37742187
DOI: 10.1016/j.celrep.2023.113167