Dual-acting Agents Research Articles

Evaluating the Biocontrol Efficacy and Antioxidant Potential of Phellinus caribaeo-quercicola-A First Report Dual-Action Endophyte From Inula racemosa Hook. F.

Phellinus caribaeo-quercicola is a basidiomycetous fungus, isolated as an endophyte in this study from the healthy and symptomless leaves of Inula racemosa Hook. f., an important medicinal herb growing in Kashmir Himalaya. This study combines morphological, molecular and phylogenetic techniques to identify the fungal endophyte, using the ITS sequence of nrDNA. A detached leaf assay was conducted to assess the pathogenicity of the fungal endophyte suggesting its mutually symbiotic relationship with the host. The authors also investigated the antifungal potential of the isolated endophytic strain to ascertain its use as a biocontrol agent. The study shows that P. caribaeo-quercicola INL3-2 strain exhibits biocontrol activity against four key fungal phytopathogens that cause significant agronomic and economic losses: Aspergillus flavus, Aspergillus niger, Fusarium solani, and Fusarium oxysporum. Notably, P. caribaeo-quercicola INL3-2 strain is highly effective against A. flavus, with an inhibition percentage of 57.63%. In addition, this study investigates the antioxidant activity of P. caribaeo-quercicola INL3-2 strain crude extracts using ethyl acetate and methanol as solvents. The results showed that the methanolic fraction of P. caribaeo-quercicola exhibits potential as an antioxidant agent, with an IC50 value of 171.90 ± 1.15 µg/mL. This investigation is first of its kind and marks the initial report of this fungal basidiomycete, P. caribaeo-quercicola, as an endophyte associated with a medicinal plant. The findings of this study highlight the potential of P. caribaeo-quercicola INL3-2 strain as a dual-action agent with both biocontrol and antioxidant properties consistent with the medicinal properties of Inula racemosa. This endophytic fungus could be a promising source of natural compounds for use in agriculture, medicine, and beyond.

DIPG-68. FLAG-003, A NOVEL, DUAL-ACTION THERAPEUTIC, DEMONSTRATES IN-VITRO ACTIVITY AGAINST DIFFUSE INTRINSIC PONTINE GLIOMA (DIPG)

Abstract BACKGROUND FLAG-003 is a novel, rationally-designed, CNS-penetrant, dual-acting agent that inhibits receptor tyrosine kinase activity and microtubule polymerization. Preclinical studies in glioblastoma (GBM) demonstrated decreased cell viability, reduced tumor volumes, decreased microvessel density, and increased survival. Remarkably, using an orthotopic DIPG model, all mice treated with FLAG-003 at 275 mg/day/orally displayed tumor regression, tumor reduction and increased survival. Given the significant preclinical activity against DIPG, as well as the known heterogeneity of DIPG, we evaluated the efficacy of FLAG-003 in vitro against a panel of DIPG cell lines. METHODS Eight DIPG cell lines hosted at the Center for Patient Derived Models (CPDM) were selected based on genomic and growth characteristics. Cells were plated on 384-well plates; 24 hours after plating, cells were dosed with 1nM to 50uM (12 step log curve) FLAG-003. Three technical replicates were performed per step. Controls consisted of positive kill control Staurosporine, negative growth control of 0.5% DMSO, or no DMSO for baseline growth. ONC201, a small molecule antagonist of DRD2/3 currently in clinical trials for DIPG, was used as a comparator. We also evaluated two GBM patient-derived models. RESULTS FLAG-003 demonstrated efficacy in all DIPG and GBM cell lines tested with IC50 less than 100nM. FLAG-003 was more potent compared to ONC201 in all models evaluated. CONCLUSIONS Single agent FLAG-003 demonstrated activity against a panel of DIPG cell lines. As next steps, we are exploring the efficacy of this drug in orthotopic DIPG PDX models. Continued development of FLAG-003 as a potential therapeutic candidate for DIPG patients is warranted and underway.

Flavonoids as dual-action agents for anticancer and anti-tooth caries: a molecular docking and dynamics simulation on MMP2 inhibition

Objective: Cancer pathogenesis is linked to matrix metalloproteinase-2 (MMP2). Numerous studies have indicated an elevated expression of MMP2 in the tissue microenvironment of different cancers, including breast, oral, prostate, ovarian, colorectal, bladder, lung, and hepatocellular carcinoma. The significant role of MMP2 in the degradation of organic compounds in dentin, causing dental caries, has been indicated by accumulating evidence. This study explored the possibility of using flavonoids as natural compounds capable of inhibiting MMP2 to meet the need for new and potent MMP2 inhibitors. Methods: The AutoDock software evaluated the binding energies between selected flavonoids and the MMP2 catalytic domain and ranked the ligands based on their inhibition constant (Ki) values and Gibbs free binding energy scores. The Discovery Studio Visualizer tool demonstrated how the highest-ranked flavonoids interact with the MMP2. Molecular dynamics was conducted for the most potent MMP2 inhibitor in a 100 ns computer simulation. Results: Kaempferol 3-rutinoside-7-sophoroside demonstrated an inhibitory effect against MMP2 with a Ki value and ΔGbinding score of 209.92 fM and −17.30 kcal/mol, respectively. This flavonoid was able to restrict MMP2 activity within a femtomolar range. This study identified eight flavonoids with Ki values in the picomolar range. According to the study, the docked pose of kaempferol 3-rutinoside-7-sophoroside within the MMP2 catalytic domain reached stability after a simulation of ~60 nanoseconds. Conclusion: Inhibition of MMP2 by flavonoids, notably kaempferol derivatives, might be an effective therapeutic strategy for cancer treatment.

Pyrazoles have a multifaceted anti-inflammatory effect targeting prostaglandin E2, cyclooxygenases and leukocytes’ oxidative burst

Elevated levels of prostaglandin E2 have been implicated in the pathophysiology of various diseases. Anti-inflammatory drugs that act through the inhibition of cyclooxygenase enzymatic activity, thereby leading to the suppression of prostaglandin E2, are often associated with several side effects due to their non-specific inhibition of cyclooxygenase enzymes. Consequently, the targeted suppression of prostaglandin E2 production with innovative molecules and/or mechanisms emerges as a compelling therapeutic strategy for the treatment of inflammatory-related diseases. Therefore, in this study, a systematic analysis of 28 pyrazole derivatives was conducted to explore their potential mechanisms for reducing prostaglandin E2 levels. In this context, the evaluation of these derivatives extended to examining their capacity to reduce prostaglandin E2in vitro in human whole blood, inhibit cyclooxygenase-1 and cyclooxygenase-2 enzymes, modulate cyclooxygenase-2 expression, and suppress oxidative burst in human leukocytes. The results enabled the establishment of significant structure-activity relationships, elucidating key determinants for their activities. In particular, the 4-styryl group on the pyrazole moiety and the presence of chloro substitutions were identified as key determinants. Pyrazole 8 demonstrated the capacity to reduce prostaglandin E2 levels by downregulating cyclooxygenase-2 expression, and pyrazole-1,2,3-triazole 18 emerged as a dual-acting agent, inhibiting human leukocytes' oxidative burst and cyclooxygenase-2 activity. Furthermore, pyrazole 26 demonstrated effective reduction of prostaglandin E2 levels through selective cyclooxygenase-1 inhibition. These results underscore the multifaceted anti-inflammatory potential of pyrazoles, providing new insights into the substitutions and structural frameworks that are beneficial for the studied activity.

Allergic Conjunctivitis: Review of Current Types, Treatments, and Trends.

Allergic conjunctivitis is an allergen-induced immune response secondary to the binding of immunoglobulin-E (IgE) to sensitized mast cells. Approximately 40% of North Americans and 20% of the world's population are impacted by some form of allergy and it continues to increase in prevalence, especially among children. Specified IgE antibodies can be found in almost all cases of exposure to seasonal or perennial allergens. Activation and degranulation of mast cells lead to increased tear levels of histamine, tryptase, leukotrienes, cytokines, and prostaglandins. The release of these factors initiates the recruitment of inflammatory cells in the conjunctival mucosa, which causes the late-phase reaction. Signs and symptoms of ocular allergies include itching, tearing, chemosis, and hyperemia, which can lead to decreased productivity and poor quality of life. Many treatment options are available to improve symptoms, including, mast cell stabilizers, antihistamines, dual-acting agents, steroids, nonsteroidal anti-inflammatory drugs (NSAIDS), and other off-label treatment modalities. This review article provides an overview of different types of allergic conjunctivitis, its pathology and immunology, and recommended methods of treatment.

Ruthenium-Cathepsin Inhibitor Conjugates for Green Light-Activated Photodynamic Therapy and Photochemotherapy.

Dysregulated cathepsin activity is linked to various human diseases including metabolic disorders, autoimmune conditions, and cancer. Given the overexpression of cathepsin in the tumor microenvironment, cathepsin inhibitors are promising pharmacological agents and drug delivery vehicles for cancer treatment. In this study, we describe the synthesis and photochemical and biological assessment of a dual-action agent based on ruthenium that is conjugated with a cathepsin inhibitor, designed for both photodynamic therapy (PDT) and photochemotherapy (PCT). The ruthenium-cathepsin inhibitor conjugate was synthesized through an oxime click reaction, combining a pan-cathepsin inhibitor based on E64d with the Ru(II) PCT/PDT fragment [Ru(dqpy)(dppn)], where dqpy = 2,6-di(quinoline-2-yl)pyridine and dppn = benzo[i]dipyrido[3,2-a:2',3'-c]phenazine. Photochemical investigations validated the conjugate's ability to release a triazole-containing cathepsin inhibitor for PCT and to generate singlet oxygen for PDT upon exposure to green light. Inhibition studies demonstrated the conjugate's potent and irreversible inactivation of purified and intracellular cysteine cathepsins. Two Ru(II) PCT/PDT agents based on the [Ru(dqpy)(dppn)] moiety were evaluated for photoinduced cytotoxicity in 4T1 murine triple-negative breast cancer cells, L929 fibroblasts, and M0, M1, and M2 macrophages. The cathepsin inhibitor conjugate displayed notable selectivity for inducing cell death under irradiation compared to dark conditions, mitigating toxicity in the dark observed with the triazole control complex [Ru(dqpy)(dppn)(MeTz)]2+ (MeTz = 1-methyl-1H-1,2,4-triazole). Notably, our lead complex is among a limited number of dual PCT/PDT agents activated with green light.

A dual-acting aldose reductase inhibitor impedes oxidative and carbonyl stress in tissues of fructose- and streptozotocin-induced rats: comparison with antioxidant stobadine

Inhibiting aldose reductase (ALR2, AR) as well as maintaining a concomitant antioxidant (AO) activity via dual-acting agents may be a rational approach to prevent cellular glucotoxicity and at least delay the progression of diabetes mellitus (DM). This study was aimed at evaluating the dual-acting AR inhibitor (ARI) cemtirestat (CMTI) on tissue oxidative stress (OS) and carbonyl stress (CS) biomarkers in rats exposed to fructose alone (F) or fructose plus streptozotocin (D; type-2 diabetic). D and F rats were either untreated or treated daily with low- or high-dose CMTI, ARI drug epalrestat (EPA) or antioxidant stobadine (STB) for 14 weeks. Malondialdehyde (MDA), glutathione S-transferase (GST), nitric oxide synthase (NOS), and catalase (CAT) were increased in the sciatic nerve of F and D. These increases were attenuated by low doses of CMTI and STB in D, but exacerbated by low-dose EPA and high-dose CMTI in F. STB and CMTI and to a lesser extent EPA improved MDA, protein-carbonyl, GST and CAT in the hearts and lungs of F and D. CMTI and STB were more effective than EPA in improving the increased MDA and protein-carbonyl levels in the kidneys of F and especially D. CMTI ameliorated renal GST inhibition in D. In the lungs, hearts, and kidneys of F and D, the GSH to GSSG ratio decreased and caspase-3 activity increased, but partially resolved with treatments. In conclusion, CMTI with ARI/AO activity may be advantageous in overcoming OS, CS, and their undesirable consequences, with low dose efficacy and limited toxicity, compared to ARI or antioxidant alone.

Battling colorectal cancer via s-triazine-based MMP-10/13 inhibitors armed with electrophilic warheads for concomitant ferroptosis induction; the first-in-class dual-acting agents

There is an increasing interest in halting CRC by combining ferroptosis with other forms of tumor cell death. However, ferroptosis induction is seldom studied in tandem with inhibiting MMPs. A combination that is expected to enhance the therapeutic outcome based on mechanistic ferroptosis studies highlighting the interplay with MMPs, especially MMP-13 associated with CRC metastasis and poor prognosis. Herein, we report new hybrid triazines capable of simultaneous MMP-10/13 inhibition and ferroptosis induction bridging the gap between their anticancer potentials. The MMP-10/13 inhibitory component of the scaffold was based on the non-hydroxamate model inhibitors. s-Triazine was rationalized as the core inspired by altretamine, an FDA-approved ferroptosis inducer. The ferroptosis pharmacophores were then installed as Michael acceptors via triazole-based spacers. The electrophilic reactivity was tuned by incorporating cyano and/or substituted phenyl groups influencing their electronic and steric properties and enriching the SAR study. Initial screening revealed the outstanding cytotoxicity profiles of the nitrophenyl-tethered chalcone 5e and the cyanoacrylohydrazides bearing p-fluorophenyl 9b and p-bromophenyl 9d appendages. 9b and 9d surpassed NNGH against MMP-10 and −13, especially 9d (IC50 = 0.16 μM). Ferroptosis studies proved that 9d depleted GSH in HCT-116 cells by a relative fold decrement of 0.81 with modest direct GPX4 inhibition, thus inducing lipid peroxidation, the hallmark of ferroptosis, by 1.32 relative fold increment. Docking presumed that 9d could bind to the MMP-10 S1′ pocket and active site His221, extend through the MMP-13 hydrophobic pocket, and interact covalently with the GPX4 catalytic selenocysteine. 9d complexed with ferrous oxide nanoparticles was 7.5 folds more cytotoxic than its free precursor against HCT-116 cells. The complex-induced intracellular iron overload, depleted GSH with a relative fold decrement of 0.12, consequently triggering lipid peroxidation and ferroptosis by a 3.94 relative fold increment. Collectively, 9d could be a lead for tuning MMPs selectivity and ferroptosis induction potential to maximize the benefit of such a combination.

Novel application potential of cinaciguat in the treatment of mixed hyperlipidemia through targeting PTL/NPC1L1 and alleviating intestinal microbiota dysbiosis and metabolic disorders

Mixed hyperlipidemia, characterized by high levels of triglycerides and cholesterol, is a key risk factor leading to atherosclerosis and other cardiovascular diseases. Existing clinical drugs usually only work on a single indicator, decreasing either triglyceride or cholesterol levels. Developing dual-acting agents that reduce both triglycerides and cholesterol remains a great challenge. Pancreatic triglyceride lipase (PTL) and Niemann–Pick C1-like 1 (NPC1L1) have been identified as crucial proteins in the transport of triglycerides and cholesterol. Here, cinaciguat, a known agent used in the treatment of acute decompensated heart failure, was identified as a potent dual inhibitor targeting PTL and NPC1L1. We presented in vitro evidence from surface plasmon resonance analysis that cinaciguat interacted with PTL and NPC1L1. Furthermore, cinaciguat exhibited potent PTL-inhibition activity. Fluorescence-labeled cholesterol uptake analysis and confocal imaging showed that cinaciguat effectively inhibited cholesterol uptake. In vivo evaluation showed that cinaciguat significantly reduced the plasma levels of triglycerides and cholesterol, and effectively alleviated high-fat diet–induced intestinal microbiota dysbiosis and metabolic disorders. These results collectively suggest that cinaciguat has the potential to be further developed for the therapy of mixed hyperlipidemia.

Chaga Mushroom Extract as a Dual-Action Agent against Microbial and Cancerous Cells: An In Vitro Study

Chaga Mushroom Extract as a Dual-Action Agent against Microbial and Cancerous Cells: An In Vitro Study

Switching from Aromatase Inhibitors to Dual Targeting Flavonoid-Based Compounds for Breast Cancer Treatment

Despite the significant outcomes attained by scientific research, breast cancer (BC) still represents the second leading cause of death in women. Estrogen receptor-positive (ER+) BC accounts for the majority of diagnosed BCs, highlighting the disruption of estrogenic signalling as target for first-line treatment. This goal is presently pursued by inhibiting aromatase (AR) enzyme or by modulating Estrogen Receptor (ER) α. An appealing strategy for fighting BC and reducing side effects and resistance issues may lie in the design of multifunctional compounds able to simultaneously target AR and ER. In this paper, previously reported flavonoid-related potent AR inhibitors were suitably modified with the aim of also targeting ERα. As a result, homoisoflavone derivatives 3b and 4a emerged as well-balanced submicromolar dual acting compounds. An extensive computational study was then performed to gain insights into the interactions the best compounds established with the two targets. This study highlighted the feasibility of switching from single-target compounds to balanced dual-acting agents, confirming that a multi-target approach may represent a valid therapeutic option to counteract ER+ BC. The homoisoflavone core emerged as a valuable natural-inspired scaffold for the design of multifunctional compounds.

Practice patterns and opinions in the treatment of allergic eye disease: A survey among Indian ophthalmologists.

Management of allergic eye disease is seldom straightforward and often challenging. We conducted an online survey to elicit opinions on the preferred practice pattern in the treatment of allergic eye disease. An online survey questionnaire was sent to all practicing ophthalmologists using social media platforms. The respondents were asked about their clinical experience and preferred treatment in various scenarios such as mild-moderate vernal keratoconjunctivitis (VKC), chronic VKC, refractory VKC, steroid responders, giant papillae, and shield ulcer. Respondents were asked about the newer molecule (alcaftadine) and reservations regarding systemic immuno-suppressants and ordering allergy tests in their practice. Ninety - one participants responded to the survey. About 57.1% of ophthalmologists reported coming across more than 10 cases per week in their practice. The most common age group was 5-10 years (61.1%), but adult onset VKC was also reported at 41.6% (1-2 per month), 37.1% (3-5 per month), and 13.5% (more than 10 per month). The disease is perennially present (36.7%), and a mixed form has been reported by 47.8% of ophthalmologists. Dual-acting agents were preferred by 40% in mild-moderate clinical variants. Topical steroids in slow tapering dosage were preferred by 86.7% in their prescription. Tacrolimus 0.03% was preferred by 65.9% and given for at least 3 months of continuous usage by 47.6% of ophthalmologists. High-dose topical steroids were preferred for giant papillae (67.8%) and Shields ulcers (68.3%) in our survey. Supratarsal steroid injection was preferred by 50% in treating refractory VKC in our survey. Allergic eye disease is a common yet annoying disease. The signs and symptoms can vary from subtle, innocuous forms to devastating variants affecting vision and day-to-day work. This survey aims to elicit responses from clinicians spreading across different geographical areas and compares responses based on experience in practice.

Dual Action of Beauveria bassiana (Hypocreales; Cordycipitaceae) Endophytic Stains as Biocontrol Agents against Sucking Pests and Plant Growth Biostimulants on Melon and Strawberry Field Plants.

Entomopathogenic fungi (EPF) can colonize plant tissues and serve crops not only as biopesticides but also as biostimulants that promote plant growth and trigger defense mechanisms. In this context, field trials were conducted evaluating two commercial strains of the entomopathogen Beauveria bassiana (Hypocreales: Cordycipitaceae), GHA (Botanigard) and PPRI 5339 (Velifer® ES) and a wild strain (AP0101) isolated from Achaia, Greece. The three strains were investigated in the field for their endophytic effects on melon Cucumis melo (Cucurbitales: Cucurbitaceae) and strawberry Fragaria sp. (Rosales: Rosaceae) plants and in particular for their ability to colonize plant tissues, control infestations of sucking insects Aphis gossypii (Hemiptera: Aphididae), Chaetosiphon fragaefolii (Hemiptera: Aphididae) and Frankliniella occidentalis (Thysanoptera: Thripidae), and improve plant growth parameters (plant height, number of flowers and fruits). All experimental fungal strains successfully colonized both plants. A significant decrease in the aphid and thrip populations was observed in the treated plants compared to the untreated control. As for plant growth, the number of flowers and fruits was significantly increased in plants treated with B. bassiana strains AP0101 and PPRI 5339. Our results clearly indicate that fungal endophytes can efficiently act as dual action agents demonstrating both insecticidal and growth-promoting effects.

An olive-derived elenolic acid stimulates hormone release from L-cells and exerts potent beneficial metabolic effects in obese diabetic mice.

Insulin resistance and progressive decline in functional β-cell mass are two key factors for developing type 2 diabetes (T2D), which is largely driven by overweight and obesity, a significant obstacle for effective metabolic control in many patients with T2D. Thus, agents that simultaneously ameliorate obesity and act on multiple pathophysiological components could be more effective for treating T2D. Here, we report that elenolic acid (EA), a phytochemical, is such a dual-action agent. we show that EA dose-dependently stimulates GLP-1 secretion in mouse clonal L-cells and isolated mouse ileum crypts. In addition, EA induces L-cells to secrete peptide YY (PYY). EA induces a rapid increase in intracellular [Ca2+]i and the production of inositol trisphosphate in L-cells, indicating that EA activates phospholipase C (PLC)-mediated signaling. Consistently, inhibition of (PLC) or Gαq ablates EA-stimulated increase of [Ca2+]i and GLP-1 secretion. In vivo, a single dose of EA acutely stimulates GLP-1 and PYY secretion in mice, accompanied with an improved glucose tolerance and insulin levels. Oral administration of EA at a dose of 50 mg/kg/day for 2 weeks normalized the fasting blood glucose and restored glucose tolerance in high-fat diet-induced obese (DIO) mice to levels that were comparable to chow-fed mice. In addition, EA suppresses appetite, reduces food intake, promotes weight loss, and reverses perturbated metabolic variables in obese mice. These results suggest that EA could be a dual-action agent as an alternative or adjuvant treatment for both T2D and obesity.

Pharmacological treatment of osteoporosis: 2022 update

Background: Osteoporosis is a skeletal disorder characterized by compromised bone strength resulting in a predisposition to fracture. Osteoporosis-related fractures can lead to pain, disability, and increased healthcare costs. We aimed to explore the guidelines and criteria for selecting medications for osteoporosis.Current Concepts: Osteoporosis medications can be classified mainly as antiresorptive drugs and osteogenesis promoters. The former includes selective estrogen receptor modulators, bisphosphonates, and receptor activators of nuclear factor kappa-B ligand inhibitors, e.g., denosumab. The latter includes human parathyroid hormone, e.g., teriparatide, and the dual-action agent, romosozumab. Selective estrogen receptor modulators (raloxifene or bazedoxifene) can be considered suitable for younger postmenopausal women with low spine bone mineral density. It also can be used for patients with low glomerular filtration rates due to low excretion in urine and patients who need dental care. Bisphosphonate has a residual effect on bone; therefore, osteonecrosis of the jaw and atypical fractures should be considered as side effects for its long-term use. Presently, denosumab is the most potent antiresorptive agent, but its favorable skeletal effects can be reversed quickly after its cessation. Therefore, subsequent antiresorptive treatment is mandatory. Romosozumab is a dual-action agent that simultaneously stimulates bone formation and inhibits bone resorption. It also needs a subsequent antiresorptive treatment.Discussion and Conclusion: Tailored treatment is needed in a patient with osteoporosis. Even in the case of the same bone density, the risk of fracture and the fracture sites differ depending on age. After setting an achievable goal of bone density within a suitable period, the appropriate medication should be selected.

Nature-Inspired O-Benzyl Oxime-Based Derivatives as New Dual-Acting Agents Targeting Aldose Reductase and Oxidative Stress.

Aldose reductase (ALR2) is the enzyme in charge of developing cellular toxicity caused by diabetic hyperglycemia, which in turn leads to the generation of reactive oxygen species triggering oxidative stress. Therefore, inhibiting ALR2 while pursuing a concomitant anti-oxidant activity through dual-acting agents is now recognized as the gold standard treatment for preventing or at least delaying the progression of diabetic complications. Herein we describe a novel series of (E)-benzaldehyde O-benzyl oximes 6a–e, 7a–e, 8a–e, and 9–11 as ALR2 inhibitors endowed with anti-oxidant properties. Inspired by the natural products, the synthesized derivatives are characterized by a different polyhydroxy substitution pattern on their benzaldehyde fragment, which proved crucial for both the enzyme inhibitory activity and the anti-oxidant capacity. Derivatives (E)-2,3,4-trihydroxybenzaldehyde O-(3-methoxybenzyl) oxime (7b) and (E)-2,3,4-trihydroxybenzaldehyde O-(4-methoxybenzyl) oxime (8b) turned out to be the most effective dual-acting products, proving to combine the best ALR2 inhibitory properties with significant anti-oxidant efficacy.

Lessons from a Single Amino Acid Substitution: Anticancer and Antibacterial Properties of Two Phospholipase A2-Derived Peptides.

The membrane-active nature of phospholipase A2-derived peptides makes them potential candidates for antineoplastic and antibacterial therapies. Two short 13-mer C-terminal fragments taken from snake venom Lys49-PLA2 toxins (p-AppK and p-Acl), differing by a leucine/phenylalanine substitution, were synthesized and their bioactivity was evaluated. Their capacity to interfere with the survival of Gram-positive and Gram-negative bacteria as well as with solid and liquid tumors was assessed in vitro. Toxicity to red blood cells was investigated via in silico and in vitro techniques. The mode of action was mainly studied by molecular dynamics simulations and membrane permeabilization assays. Briefly, both peptides have dual activity, i.e., they act against both bacteria, including multidrug-resistant strains and tumor cells. All tested bacteria were susceptible to both peptides, Pseudomonas aeruginosa being the most affected. RAMOS, K562, NB4, and CEM cells were the main leukemic targets of the peptides. In general, p-Acl showed more significant activity, suggesting that phenylalanine confers advantages to the antibacterial and antitumor mechanism, particularly for osteosarcoma lines (HOS and MG63). Peptide-based treatment increased the uptake of a DNA-intercalating dye by bacteria, suggesting membrane damage. Indeed, p-AppK and p-Acl did not disrupt erythrocyte membranes, in agreement with in silico predictions. The latter revealed that the peptides deform the membrane and increase its permeability by facilitating solvent penetration. This phenomenon is expected to catalyze the permeation of solutes that otherwise could not cross the hydrophobic membrane core. In conclusion, the present study highlights the role of a single amino acid substitution present in natural sequences towards the development of dual-action agents. In other words, dissecting and fine-tuning biomembrane remodeling proteins, such as snake venom phospholipase A2 isoforms, is again demonstrated as a valuable source of therapeutic peptides.

Transcription factors specificity protein and nuclear receptor 4A1 in pancreatic cancer.

Specificity protein (Sp) transcription factors (TFs) Sp1, Sp3 and Sp4, and the orphan nuclear receptor 4A1 (NR4A1) are highly expressed in pancreatic tumors and Sp1 is a negative prognostic factor for pancreatic cancer patient survival. Results of knockdown and overexpression of Sp1, Sp3 and Sp4 in pancreatic and other cancer lines show that these TFs are individually pro-oncogenic factors and loss of one Sp TF is not compensated by other members. NR4A1 is also a pro-oncogenic factor and both NR4A1 and Sp TFs exhibit similar functions in pancreatic cancer cells and regulate cell growth, survival, migration and invasion. There is also evidence that Sp TFs and NR4A1 regulate some of the same genes including survivin, epidermal growth factor receptor, PAX3-FOXO1, α5- and α6-integrins, β1-, β3- and β4-integrins; this is due to NR4A1 acting as a cofactor and mediating NR4A1/Sp1/4-regulated gene expression through GC-rich gene promoter sites. Several studies show that drugs targeting Sp downregulation or NR4A1 antagonists are highly effective inhibitors of Sp/NR4A1-regulated pathways and genes in pancreatic and other cancer cells, and the triterpenoid celastrol is a novel dual-acting agent that targets both Sp TFs and NR4A1.

Vortioxetine as a new frontier in the treatment of chronic neuropathic pain: a review and update

Chronic neuropathic pain (CNP) is a disabling medical condition that impairs the health-related quality-of-life of affected patients. A high prevalence of anxiety, depression, sleep disturbance and cognitive impairment has frequently been reported in association with CNP, making the management of this disease complex and often multidisciplinary. Dual-acting agents such as selective serotonin and noradrenalin reuptake inhibitors (SNRIs) are considered particularly useful in the modulation of pain and in treatment of the mood disorders frequently associated with CNP. Recent evidence suggests that the top-down inhibitory control of pain involves the engagement and enhancement of descending endogenous opioidergic, cannabinoid and serotonergic systems, with the effect of serotonin being particularly related to the receptor subtypes that are preferentially activated; indeed serotonin induces analgesia via activation of 5-HT7 receptors and hyperalgesia via activation of 5-HT3 receptors. Vortioxetine (VO) is a novel multimodal serotonergic antidepressant with a unique mechanism of action. It has been demonstrated recently in experimental and clinical studies to have efficacy on pain hypersensitivity and on mood disorders. This drug inhibits the serotonin transporter with a high affinity, antagonises the 5-HT3, 5-HT1D and 5HT7 serotonin receptors, and activates the 5-HT1A and 5-HT1B receptors. In clinical studies, VO has proved effective at a dose of 10–20 mg/daily in short- and long-term treatment of patients with chronic orofacial pain, demonstrating a higher rate of clinical response and remission, a better acceptability, safety rate and tolerability, and a lower latency of action compared with other antidepressants. In the light of these recent findings, VO may be considered as a new pharmacological treatment also in relation to various types of CNP, particularly in elderly patients with concomitant mood disorders and cognitive impairment. The purpose of this review is to provide an up-to-date overview of the pharmacology and clinical applications of VO and to highlight its potential therapeutic properties and advantages in the management of CNP.

Novel Sulfonamide-Based Analogs of Metformin Exert Promising Anti-Coagulant Effects without Compromising Glucose-Lowering Activity.

Metformin, one of the most frequently prescribed oral anti-diabetic drugs, is characterized by multidirectional activity, including lipid lowering, cardio-protective and anti-inflammatory properties. This study presents synthesis and stability studies of 10 novel sulfonamide-based derivatives of metformin with alkyl substituents in the aromatic ring. The potential of the synthesized compounds as glucose-lowering agents and their effects on selected parameters of plasma and vascular hemostasis were examined. Compounds with two or three methyl groups in the aromatic ring (6, 7, 9, 10) significantly increased glucose uptake in human umbilical vein endothelial cells (HUVECs), e.g., 15.8 µmol/L for comp. 6 at 0.3 µmol/mL versus 11.4 ± 0.7 µmol/L for control. Basic coagulation studies showed that all examined compounds inhibit intrinsic coagulation pathway and the process of fibrin polymerization stronger than the parent drug, metformin, which give evidence of their greater anti-coagulant properties. Importantly, synthesized compounds decrease the activity of factor X, a first member of common coagulation pathway, while metformin does not affect coagulation factor X (FX) activity. A multiparametric clot formation and lysis test (CL-test) revealed that the examined compounds significantly prolong the onset of clot formation; however, they do not affect the overall potential of clot formation and fibrinolysis. Erythrotoxicity studies confirmed that none of the synthesized compounds exert an adverse effect on erythrocyte integrity, do not contribute to the massive hemolysis and do not interact strongly with the erythrocyte membrane. In summary, chemical modification of metformin scaffold into benzenesulfonamides containing alkyl substituents leads to the formation of potential dual-action agents with comparable glucose-lowering properties and stronger anti-coagulant activity than the parent drug, metformin.