Different Mechanisms Of Action Research Articles

Search for new biologically active compounds: in vitro studies of antitumor and antimicrobial activity of dirhodium(II,II) paddlewheel complexes.

Four neutral Rh1-Rh4 complexes of the general formula [Rh2(CH3COO)4L2], where L is an N-alkylimidazole ligand, were synthesized and characterized using various spectroscopic techniques, and in the case of Rh4 the crystal structure was confirmed. Investigation of the interactions of these complexes with HSA by fluorescence spectroscopy revealed that the binding constants Kb are moderately strong (∼104 M-1), and site-marker competition experiments showed that the complexes bind to Heme site III (subdomain IB). Competitive binding studies for CT DNA using EB and HOE showed that the complexes bind to the minor groove, which was also confirmed by viscosity experiments. Molecular docking confirmed the experimental data for HSA and CT DNA. Antimicrobial tests showed that the Rh2-Rh4 complexes exerted a strong inhibitory effect on G+ bacteria B. cereus and G- bacteria V. parahaemolyticus as well as on the yeast C. tropicalis, which showed a higher sensitivity compared to fluconazole. The cytotoxic activity of Rh1-Rh4 complexes tested on three cancer cell lines (HeLa, HCT116 and MDA-MB-231) and on healthy MRC-5 cells showed that all investigated complexes elicited more efficient cytotoxicity on all tested tumor cells than on control cells. Investigation of the mechanism of action revealed that the Rh1-Rh4 complexes inhibit cell proliferation via different mechanisms of action, namely apoptosis (increase in expression of the pro-apoptotic Bax protein and caspase-3 protein in HeLa and HCT116 cells; changes in mitochondrial potential and mitochondrial damage; release of cytochrome c from the mitochondria; cell cycle arrest in G2/M phase in both HeLa and HCT116 cells together with a decrease in the expression of cyclin A and cyclin B) and autophagy (reduction in the expression of the protein p62 in HeLa and HCT116 cells).

A synergistic therapy against influenza virus A/H1N1/PR8 by a HA1 specific neutralizing single-domain VL and an RNA hydrolyzing scFv.

The emergence of anti-influenza drug-resistant strains poses a challenge for influenza therapy due to mutations in the virus's surface protein. Recently, there has been increasing interest in combination therapy consisting of two or more drugs as a potential alternative approach, aiming to enhance therapeutic efficacy. In this study, we investigated a novel synergistic therapy with a vertical effect using a single-domain VL-HA1-specific antibody against H1N1/PR8 and a horizontal effect using an RNA catalytic antibody with broad-spectrum influenza antiviral drug. We isolated a single-domain VL-HA1-specific (NVLH8) antibody binding to the virus particles showing a neutralizing activity against influenza virus A, specifically H1N1/PR8, as determined by the reduction in plaque number and lower viral HA protein expression in vitro. The neutralizing antibody likely prevented the viral entry, specifically at the viral genome-releasing step. Additionally, the 3D8 scFv hydrolyzed viral RNAs in the cytoplasm, including mRNA, vRNA, and cRNA in MDCK cells. The combined treatment of neutralizing antibodies for a vertical effect and 3D8 scFv for a horizontal effect produced a synergistic effect providing a novel approach against viral diseases when compared with a single treatment. Our results indicated that combining treatment, in particular two proteins exhibiting different mechanisms of action increased the antiviral activity against the influenza virus.

A comparative evaluation of efficacy and safety of the combination of piroxicam with tramadol versus pentazocine in post-cesarean pain management

Background: Acute pain management enhances the overall quality of life for individuals having cesarean sections. Although it is a basic human right, pain treatment following a cesarean section lacks a gold standard. Multimodal analgesia is now recommended to aid recovery and mitigate the adverse effects of strong pain-relieving medications like opioids. Multimodal analgesic therapy, with the goal of obtaining synergistic or additive analgesia with fewer side effects, is by combining lesser amounts of each drug with different mechanisms of action. Aims and Objectives: The objective of the study was to compare the efficacy and safety of the combination of piroxicam with tramadol versus pentazocine in post-cesarean pain management. Materials and Methods: Following cesarean section after skin closure, cases were randomly assigned into two groups of thirty cases each. Group A was administered tramadol 100 mg+piroxicam 20 mg and Group B received pentazocine 30 mg+piroxicam 20 mg by intramuscular injection. Diclofenac 75 mg served as the rescue pain relief medication. The main focus was pain control, evaluated using the Visual Analog Scale (VAS). Secondary outcomes included sedation levels and the duration until additional pain relief was required. The safety profile of the medications was assessed by monitoring adverse drug reactions. Statistical analysis involved methods such as student’s t-test, analysis of variance, and post hoc testing. Results: Both the groups were comparable and statistically significant in VAS, time to rescue analgesia, and mean sedation score. Conclusion: The combination of piroxicam with tramadol versus pentazocine is effective and considered as an acceptable method of pain relief after cesarean delivery.

BeatProfiler: Multimodal In Vitro Analysis of Cardiac Function Enables Machine Learning Classification of Diseases and Drugs.

Goal: Contractile response and calcium handling are central to understanding cardiac function and physiology, yet existing methods of analysis to quantify these metrics are often time-consuming, prone to mistakes, or require specialized equipment/license. We developed BeatProfiler, a suite of cardiac analysis tools designed to quantify contractile function, calcium handling, and force generation for multiple in vitro cardiac models and apply downstream machine learning methods for deep phenotyping and classification. Methods: We first validate BeatProfiler's accuracy, robustness, and speed by benchmarking against existing tools with a fixed dataset. We further confirm its ability to robustly characterize disease and dose-dependent drug response. We then demonstrate that the data acquired by our automatic acquisition pipeline can be further harnessed for machine learning (ML) analysis to phenotype a disease model of restrictive cardiomyopathy and profile cardioactive drug functional response. To accurately classify between these biological signals, we apply feature-based ML and deep learning models (temporal convolutional-bidirectional long short-term memory model or TCN-BiLSTM). Results: Benchmarking against existing tools revealed that BeatProfiler detected and analyzed contraction and calcium signals better than existing tools through improved sensitivity in low signal data, reduction in false positives, and analysis speed increase by 7 to 50-fold. Of signals accurately detected by published methods (PMs), BeatProfiler's extracted features showed high correlations to PMs, confirming that it is reliable and consistent with PMs. The features extracted by BeatProfiler classified restrictive cardiomyopathy cardiomyocytes from isogenic healthy controls with 98% accuracy and identified relax90 as a top distinguishing feature in congruence with previous findings. We also show that our TCN-BiLSTM model was able to classify drug-free control and 4 cardiac drugs with different mechanisms of action at 96% accuracy. We further apply Grad-CAM on our convolution-based models to identify signature regions of perturbations by these drugs in calcium signals. Conclusions: We anticipate that the capabilities of BeatProfiler will help advance in vitro studies in cardiac biology through rapid phenotyping, revealing mechanisms underlying cardiac health and disease, and enabling objective classification of cardiac disease and responses to drugs.

GSH/pH dual responsive chitosan nanoparticles for reprogramming M2 macrophages and overcoming cancer chemoresistance.

The combination of two or more drugs with different mechanisms of action is a promising strategy for circumventing multidrug resistance (MDR). However, the antitumor effect of nanosystems is usually limited due to the simultaneous release of different payloads at a single location rather than at their respective sites of action. Herein, we report a GSH and pH dual responsive nanoplatform encapsulated with doxorubicin (DOX) and resiquimod (R848) (GPNP) for combinatorial chemotherapy against cancer cells with drug resistance. GPNP possesses a core-shell structure wherein the polymer shell detaches in the acidic and sialic acid (SA)-rich environment. This leads to the release of R848 into the tumor microenvironment (TME), thereby reprogramming M2 macrophages into M1 macrophages and exposing the core CS(DOX)-PBA to kill MCF-7/ADR cells. Additionally, the nitric oxide (NO) generated by M1 macrophages can suppress the P-glycoprotein (P-gp) expression to reduce the efflux of chemotherapy drugs, thus playing a combined role in overcoming MDR. In vitro studies have demonstrated the effectiveness of GPNP in reprogramming M2 macrophages and inducing apoptosis in MCF-7/ADR cells, resulting in enhanced antitumor efficacy. This work proposed an effective combination strategy to combat chemoresistance, providing new insights into the development of innovative combinatorial therapies against MDR tumors.

A Novel Mitochondrial Targeted Compound Phosundoxin Showing Potent Antifungal Activity against Common Clinical Pathogenic Fungi.

The current increase in resistance to antifungal drugs indicates that there is an urgent need to explore novel antifungal drugs with different mechanisms of action. Phosundoxin is a biphenyl aliphatic amide using a TPP-targeting strategy which targets mitochondria. To provide insights into the antifungal activities of phosundoxin, the antifungal susceptibility testing of phosundoxin was conducted on 158 pathogenic fungi and compared to that of traditional azole drugs. Phosundoxin displayed a broad-spectrum antifungal activity on all the tested yeast-like and filamentous fungi ranging from 2 to 16 mg/L. In particular, azole-resistant clinical isolates of Candida albicans were susceptible to phosundoxin with the same MICs as azole-susceptible C. albicans. Transcriptome analysis on azole-resistant C. albicans identified 554 DEGs after treatment with phosundoxin. By integrating GO and KEGG pathway enrichment analysis, the antifungal activity of phosundoxin was related to impairment of mitochondrial respiratory chain function. Acute oral and percutaneous toxicity of phosundoxin to rats showed that the compound phosundoxin were mild toxicity and LD50 was above 5000 mg/kg body weight in rats. This study demonstrated the potential of phosundoxin as an antifungal agent for the treatment of common fungal infection and contributed to providing insights into the mechanisms of action of phosundoxin against C. albicans.

Screening of anti-inflammatory activity of 4.5-dihydroisoxazol-5-carboxamide (PAR-2 inhibitors) based on formaldehyde oedema model among white lab rats


 Introduction: Rheumatoid arthritis (RА) is an immune-inflammatory disease intrinsic to up to 1.0% of the world’s population. Standard drugs for RA therapy are basic medications, glucocorticoids and non-steroid anti-inflammatory drugs, which often only ease or hinder the course of disease, not curing the patient completely. Also, on the average 20-50 % of patients are unresponsive to treatment, allergic to the prescribed drugs or find them ineffective. That is why medications with a different mechanism of action are being widely researched, some of them being antagonists of proteinase-activated receptors (PAR-2).
 
 
 Materials and Methods: The inflammatory process was reproduced by injecting a 2% solution of neutral formalin in a volume of 0.1 mL under the aponeurosis of the posterior left foot. A total of 84 white rats were used in the experiment. Diclofenac sodium was administered as a reference drug.
 
 
 Results and Discussion: An experiment on researching the impact of 5 samples of derivatives of 4.5-dihydroisoxazol-5-carboxamide on formalin oedema development among rats showed that the compound R001, compared with other substances studied, differs in the late onset of the therapeutic effect when ingested; the restoration of the foot volume to the initial level occurs only after the introduction of R005, R004 and R002. R005 to a greater extent than other compounds prevents the development of edema and has greater therapeutic efficacy than diclofenac sodium both with intragastric administration and subcutaneous injection.
 
 
 Conclusion: All five compounds in question showed anti-inflammatory activity, with the spectrum not so unequivocal both in qualitative and quantitative values.

New Frontiers in Monoclonal Antibodies for Relapsed/Refractory Diffuse Large B-Cell Lymphoma.

Diffuse large B-cell lymphoma (DLBCL) is the most common aggressive lymphoma. Approximately 60% of patients are cured with R-CHOP as a frontline treatment, while the remaining patients experience primary refractory or relapsed disease (R/R). The prognosis for R/R DLBCL patients who are neither eligible for autologous stem-cell transplantations nor CAR-T-cell treatment is poor, representing an important unmet need. Monoclonal antibodies (mAbs) have dramatically improved therapeutic options in anti-cancer strategies, offering new opportunities to overcome chemo-refractoriness in this challenging disease, even in cases of primary non-responder DLBCL. Several novel mAbs, characterized by different mechanisms of action and targets, are now available for R/R DLBCL. Unbound mAbs induce an immune response against cancer cells, triggering different mechanisms, including antibody-dependent cellular cytotoxicity (ADCC), activation of antibody-dependent cell-mediated phagocytosis (ADCP) and complement-dependent cytotoxicity (CDC). Antibody-drug conjugates (ADCs) and radioimmunotherapy (RIT), respectively, deliver a cytotoxic payload or a beta-emitter radionuclide to the targeted cells and nearby bystanders. Bispecific T-cell engagers (BiTes) and immune checkpoint inhibitors (ICIs) redirect and enhance the immune response against tumor cells. Here, we review therapeutic strategies based on monoclonal antibodies for R/R DLBCL.

Ascorbic acid in cancer management – time for a second look

Introduction and aim. Over the past decades, the hypotheses that ascorbic acid (AA) can play a role as an anti-neoplastic therapy have generated many conflicting reports. Despite the controversies, mounting evidence has shown that AA has the potential to play a role as an anti-neoplastic agent. Recent studies have unraveled its pharmacokinetics and various mechanism of action on cancer cells. This has spawned different preclinical studies with reports of good activities against various cancers. Material and methods. A review of the literature regarding ascorbic acid in the management of cancer was performed using the PubMed database. The research was limited to abstracts and available full-text articles. Analysis of the literature. Clinical trials have also demonstrated its safety and tolerability across different dosages. AA has been noted as a multitargeting agent that acts as a pro-oxidative cytotoxic agent, anti-cancer epigenetic regulator and immune modulator. AA has also been shown act synergistically with standard chemotherapy regimens in different cancers. Despite its potentials, phase III clinical trials are seriously lacking. The recent phase III VITALITY study shows that AA may play a role as an adjunct targeted therapy for ras-mutated cancers. Therefore, there is need to for more standardized clinical trials to help identify cancer subtypes and AA combination regimens that can show the most benefits. In this review, the pleiotropic mechanism of action of AA was explored as well as various preclinical and clinical studies in cancer therapy. In addition, recommendations were also made for effective strategies towards an AA and standard cancer regimens in treatment as well as future directions. Ascorbic acid has been shown to induce cell death in various cancer types through different mechanisms of action. Several clinical trials and case reports have shown its efficacy in combination chemotherapy, and the pharmacological route of action can be either intravenous or oral. However, it can impair the actions of some drugs when given in combination. Also, dosage should be determined for maximal pharmacologic action. Conclusion. Ascorbic acid has the potential to provide safe and cost-effective antineoplastic treatment option especially in combination therapy. Its potential needs to be further investigated through clinical trials.

Biochemical indicators used in ecological monitoring of surface waters

The work is devoted to the search for promising test systems for ecological monitoring of surface waters by comparing the effectiveness of detecting low concentrations of various types of pesticides in the aquatic environment by traditional morphological and biochemical research methods.
 Allium cepa L. and the hydatophyte plant Elodea canadensis Michx. were used as test objects because it is immersed in the aquatic environment during its entire life cycle and is in the most complete contact with all the toxicants present in the water.
 It was found that the traditionally used test reactions of plants cannot always reflect a potentially dangerous exceedance of the MPC of toxicants in the aquatic environment.
 The possibility of using catalase activity as a sensitive bioassay for the presence of low concentrations of herbicides with different mechanisms of action in the water environment was investigated.
 Correlation analysis has been conducted, and Pearson's coefficients have been calculated to quantify the relationship between the concentration of herbicides present in water and the degree of manifestation of test reactions by the research objects.
 The highest level of correlation between the increase in the concentration of herbicides in water and the test reactions of elodea was demonstrated by biochemical indicators, and the higher significance of the correlation was observed at 4-day exposure of plants in the presence of the herbicide.

Dexamethasone and granulocyte colony-stimulating factor alter the representation of cellular patterns and neurotisation of regenerative neuroma

Aim. To evaluate the changes in the total cellularity (Nuc) of the rat sciatic nerve regenerative neuroma (RegN) and its representation of CD90, CD44, CD146, and CD133 positive cells, as well as its neurotization under the conditions of dexamethasone (Dex) and granulocyte colony-stimulating factor (GCSF). Materials and methods. After injections of dexamethasone and granulocyte colony-stimulating factor in the regenerative neuroma of 168 male Wistar rats, CD90, CD44, CD146 and CD133 positive cells were detected immunohistochemically in the regenerative neuroma. Its total cellularity and neurotization were determined and statistical processing of the obtained data was performed. Results. It was found that dexamethasone and granulocyte colony-stimulating factor change the representation of cellular patterns and neurotization of regenerative neuroma. Conclusions. The amount of neurotization of the regeneration neuroma directly depends on the specific amount of Schwann cells in its composition. Dex and GCSF, despite different mechanisms of action, lead to an increase in the content of neuroleumocytes in RegN.

Therapeutic potential of mangiferin in cancer: Unveiling regulatory pathways, mechanisms of action, and bioavailability enhancements - An updated review.

Mangiferin (MGF) is a phenolic compound, which is a major source of MGF is the mango tree. MGF possesses some antioxidant, anti-inflammatory, and cytoprotective properties, enabling it to play its role against various diseases such as diabetes, obesity, lung injuries, and cancer. The word "Cancer" depicts an uncontrolled and abnormal growth of cells. This review paper reveals MGF's therapeutic, curative and protective potential impact against lung, liver, ovarian, prostate, breast, stomach, and oral cancers. MGF is used in various types of research in the form of powder, liquid extract, intramuscular, intravenous, nanoparticles coated with gold, in the form of a solution, or in combination with other drugs to evaluate synergistic effects. Many studies showed that MGF is safe to use but has less bioavailability in the body and 0.111 mg/mL solubility in water. However, certain studies indicated that its bioavailability and retention time increased when taken in the form of nanoparticles and in combination with other drugs. MGF also increases the sensitivity of other drugs (i.e., cisplatin) resistant to tumors. MGF has different mechanisms of action for different cancers. It mainly targets enzymes, interleukins, tumor growth factors, signaling pathways, apoptotic proteins, and genes to inhibit the growth of tumors, volume, angiogenesis, cellular functionality, further progression, and movement to other areas of the body. Moreover, MGF increases apoptosis and body weight with no or fewer side effects on normal cells. MGF unveiled a novel gate toward the treatment of cancer. Further research and human trials are needed in this regard.

Co-assembly of polymeric conjugates sensitizes neoadjuvant chemotherapy of triple-negative breast cancer with reduced systemic toxicity

Rational design of polymeric conjugates could greatly potentiate the combination therapy of solid tumors. In this study, we designed and prepared two polymeric conjugates (HT-DTX and PEG-YC-1), whereas the drugs were attached to the PEG via a linker sensitive to cathepsin B, over-expressed in TNBC. Stable nanostructures were formed by these two polymer prodrug conjugates co-assembly (PPCC). The stimuli-responsiveness of PPCC was confirmed, and the size shrinkage under tumor microenvironment would facilitate the penetration of PPCC into tumor tissue. In vitro experiments revealed the molecular mechanism for the synergistic effect of the combination of DTX and YC-1. Moreover, the systemic side effects were significantly diminished since the biodistribution of PPCC was improved after i.v. administration in vivo. In this context, the co-assembled nano-structural approach could be employed for delivering therapeutic drugs with different mechanisms of action to exert a synergistic anti-tumor effect against solid tumors, including triple-negative breast cancer. Statement of significance•Co-assembly of polymeric prodrug conjugates could form stable and homogeneous nanostructures, improving cellular uptake by cancer cells and in vivo tumor penetration and retention.•Co-delivery of neoadjuvant therapeutic drug (DTX) and HIF-1α inhibitor (YC-1) synergizes the anti-tumor effect by affecting HIF-1α expression and G2/M phase arrest.•Polymer prodrug conjugates co-assembly (PPCC) could reverse tumor resistance to neoadjuvant therapy, retard tumor progression, and prevent lung metastasis with reduced systemic toxicity in a murine triple-negative breast cancer model.

Screening and verification of antiviral compounds against HSV-1 using a method based on a plaque inhibition assay

BackgroundHerpes simplex virus type 1 (HSV-1) infection is a common viral disease that mainly causes oral lesions, but can also cause genital lesions in some instances. Current treatments with nucleoside analogs are limited by the emergence of drug resistance. Therefore, novel anti-HSV-1 drugs are urgently needed.MethodsIn this study, we screened a library of 2080 compounds for anti-HSV-1 activity using a plaque formation assay. We selected 11 potential inhibitors of HSV-1 and further evaluated their antiviral effects by plaque reduction assay and real-time polymerase chain reaction (qPCR).ResultsFive compounds, namely ginsenoside Rd, brassinolide, rosamultin, 3’-hydroxy puerarin, and clinafloxacin HCl, showed potent anti-HSV-1 activity and completely suppressed plaque formation at a concentration of 10 µM. Among them, clinafloxacin HCl, a fluoroquinolone antibiotic, exhibited a high selectivity index for HSV-1.ConclusionsOur findings suggest that these five compounds have potential antiviral properties against HSV-1 and may have different mechanisms of action. Further studies are warranted to elucidate the antiviral mechanisms of these compounds and to explore their therapeutic potential for HSV-1 infection.

Comparison of the efficacy of anti-diabetic medications as add-on to metformin in type 2 diabetes mellitus from a real-world database

BackgroundMetformin is recommended as a first-line drug in the guidelines of the treatment for type 2 diabetes mellitus. However, high-quality evidence from clinical trials directly comparing the degree of hypoglycemic effect of combination therapy of metformin and a hypoglycemic agent with a different mechanism of action with that of monotherapy of a hypoglycemic drug is lacking. We aimed to examine whether combination therapy of hypoglycemic agents with metformin showed antagonism, addition, or synergism compared to monotherapy with hypoglycemic agents other than metformin regarding hemoglobin A1c levels.MethodsThis retrospective cohort study used a medical information database in Japan. Non-insulin anti-hyperglycemic agents with different mechanisms of action were classified into eight drug classes. A monotherapy cohort and a combination therapy added to the metformin cohort were defined. The change in hemoglobin A1c levels was evaluated to compare the treatment effect between the cohorts.ResultsA total of 13,359 patients with type 2 diabetes mellitus in the monotherapy cohort and 1,064 in the metformin combination therapy cohort were identified. A comparison of the change from baseline HbA1c level by drug class between the two cohorts showed a similar trend. Among those treated with dipeptidyl peptidase-4 inhibitor and sodium-glucose co-transporter-2 inhibitor, no clinically significant difference was observed between the two cohorts (0.00% and -0.07% for unadjusted, 0.15% and -0.03% for propensity score matching-adjusted, and 0.09% and -0.01% for inverse probability treatment weighting-adjusted analysis).ConclusionsAccording to the results of this study, the effect of dipeptidyl peptidase-4 inhibitor or sodium-glucose co-transporter-2 inhibitor added to metformin seems to be additive with respect to the reduction in hemoglobin A1c.

Small-molecule targeting AMPA-mediated excitotoxicity has therapeutic effects in mouse models for multiple sclerosis.

While most research and treatments for multiple sclerosis (MS) focus on autoimmune reactions causing demyelination, it is possible that neurodegeneration precedes the autoimmune response. Hence, glutamate receptor antagonists preventing excitotoxicity showed promise in MS animal models, though blocking glutamate signaling prevents critical neuronal functions. This study reports the discovery of a small molecule that prevents AMPA-mediated excitotoxicity by targeting an allosteric binding site. A machine learning approach was used to screen for small molecules targeting the AMPA receptor GluA2 subunit. The lead candidate has potent effects in restoring neurological function and myelination while reducing the immune response in experimental autoimmune encephalitis and cuprizone MS mouse models without affecting basal neurotransmission or learning and memory. These findings facilitate development of a treatment for MS with a different mechanism of action than current immune modulatory drugs and avoids important off-target effects of glutamate receptor antagonists. This class of MS therapeutics could be useful as an alternative or complementary treatment to existing therapies.

The future paradigm of HMA + VEN or targeted inhibitor approaches: sequencing or triplet combinations in AML therapy.

The routine use of next-generation sequencing methods has underscored the genetic and clonal heterogeneity of acute myeloid leukemia (AML), subsequently ushering in an era of precision medicine-based targeted therapies exemplified by the small-molecule inhibitors of FLT3, IDH1/IDH2, and BCL2. This advent of targeted drugs in AML has broadened the spectrum of antileukemic therapies, and the approval of venetoclax in combination with a hypomethylating agent has been a welcome addition to our AML patients unable to tolerate intensive chemotherapy. Mounting evidence demonstrates that molecularly targeted agents combined with epigenetic therapies exhibit synergistic augmented leukemic cell kill compared to single-agent therapy. With such great power comes greater responsibility in determining the appropriate frontline AML treatment regimen in a molecularly defined subset and identifying safe and effective combination therapies with different mechanisms of action to outmaneuver primary and secondary resistance mechanisms in AML.

A shared mechanism for TNP-ATP recognition by members of the P2X receptor family

P2X receptors (P2X1–7) are non-selective cation channels involved in many physiological activities such as synaptic transmission, immunological modulation, and cardiovascular function. These receptors share a conserved mechanism to sense extracellular ATP. TNP-ATP is an ATP derivative acting as a nonselective competitive P2X antagonist. Understanding how it occupies the orthosteric site in the absence of agonism may help reveal the key allostery during P2X gating. However, TNP-ATP/P2X complexes (TNP-ATP/human P2X3 (hP2X3) and TNP-ATP/chicken P2X7 (ckP2X7)) with distinct conformations and different mechanisms of action have been proposed. Whether these represent species and subtype variations or experimental differences remains unclear. Here, we show that a common mechanism of TNP-ATP recognition exists for the P2X family members by combining enhanced conformation sampling, engineered disulfide bond analysis, and covalent occupancy. In this model, the polar triphosphate moiety of TNP-ATP interacts with the orthosteric site, while its TNP-moiety is deeply embedded in the head and dorsal fin (DF) interface, creating a restrictive allostery in these two domains that results in a partly enlarged yet ion-impermeable pore. Similar results were obtained from multiple P2X subtypes of different species, including ckP2X7, hP2X3, rat P2X2 (rP2X2), and human P2X1 (hP2X1). Thus, TNP-ATP uses a common mechanism for P2X recognition and modulation by restricting the movements of the head and DF domains which are essential for P2X activation. This knowledge is applicable to the development of new P2X inhibitors.

Noncanonical-NF-κB activation and DDX3 inhibition reduces the HIV-1 reservoir by elimination of latently infected cells ex-vivo.

HIV-1 continues to be a major global health challenge. Current HIV-1 treatments are effective but need lifelong adherence. An HIV-1 cure should eliminate the latent viral reservoir that persists in people living with HIV-1. Different methods have been investigated that focus on reactivation and subsequent elimination of the HIV-1 reservoir, and it is becoming clear that a combination of compounds with different mechanisms of actions might be more effective. Here, we target two host factors, inhibitor of apoptosis proteins that control apoptosis and the DEAD-box helicase DDX3, facilitating HIV mRNA transport/translation. We show that targeting of these host factors with SMAC mimetics and DDX3 inhibitors induce reversal of viral latency and eliminate HIV-1-infected cells in vitro and ex vivo.

Intranasal combo: fixed-dose combination of mometasone furoate and olopatadine hydrochloride in therapeutic strategies for rhinosinusitis.

A novel strategy for the treatment of allergic rhinitis results from the innovative combination of antihistamine and intranasal corticosteroid drugs. By combining two preparations with different mechanism of action, this novel approach facilitates quick and effective controls of all upper respiratory tract allergy symptoms. The article presents the results of a study of olopatadine hydrochloride and mometasone furoate fixed-dose combination (GSP301) administered intranasally from a spray formulation, with an attempt at positioning the treatment within the ARIA and EPOS guidelines.