Discovery of (E)-3-(4-chlorophenyl)-N-(5-hydroxypentyl)acrylamide among N-substituted cinnamamide derivatives as a novel cosmetic ingredient for hyperpigmentation.

Hyperpigmentation disorders may result from inappropriate melanin deposition and/or excessive melanin synthesis. They are classified mainly as aesthetic problems, but they can significantly affect human health by decreasing self-esteem. There are available only limited treatment options for hyperpigmentation disorder, among others, cosmetic products applied topically. Depigmenting ingredients were found to be ineffective and characterized by various side effects. As a result, many efforts are made to discover novel, potent, and safe melanogenesis inhibitors for possible use in topical cosmetic depigmenting formulations. Cinnamic acid derivatives constitute a widely tested group for that purpose. This article reports research in the group of N-alkyl cinnamamide derivatives (un)substituted in phenyl ring. Among tested series, (E)-3-(4-chlorophenyl)-N-(5-hydroxypentyl)acrylamide (compound 21) showed the most promising inhibitory properties in mushroom tyrosinase assay (IC50 = 36.98 ± 1.07 µM for monophenolase activity, IC50 = 146.71 ± 16.82 µM for diphenolase activity) and melanin production inhibition in B16F10 mouse melanoma cell line at concentration 6.25 µM resulting probably from decreasing of Tyr, Mitf, Tyrp-1, and Tyrp-2 genes expression. This compound also showed melanin production inhibitory properties in pigmented reconstructed human epidermis when used in 1 % and 2 % solutions in 50 % PEG400. In vitro evaluation of its safety profile showed no cytotoxicity to human keratinocytes HaCaT, human skin fibroblasts BJ, and human primary epidermal melanocytes HEMa, no mutagenicity in the Ames test, no genotoxicity in micronucleus test, no phototoxicity, as well as no skin irritation potential tested in PEG400 solution. This compound was also shown to penetrate across the epidermis to reach the possible site of action. The performed research led to classify (E)-3-(4-chlorophenyl)-N-(5-hydroxypentyl)acrylamide as a novel potential depigmenting cosmetic ingredient.

Development of Novel Alaninamide Derivatives with Anticonvulsant Activity and Favorable Safety Profiles in Animal Models.

In our current study, we developed a focused series of original ((benzyloxy)benzyl)propanamide derivatives that demonstrated potent activity across in vivo mouse seizure models, specifically, maximal electroshock (MES) and 6 Hz (32 mA) seizures. Among these derivatives, compound 5 emerged as a lead molecule, exhibiting robust protection following intraperitoneal (i.p.) injection, as follows: ED50 = 48.0 mg/kg in the MES test, ED50 = 45.2 mg/kg in the 6 Hz (32 mA) test, and ED50 = 201.3 mg/kg in the 6 Hz (44 mA) model. Additionally, compound 5 displayed low potential for inducing motor impairment in the rotarod test (TD50 > 300 mg/kg), indicating a potentially favorable therapeutic window. In vitro toxicity assays further supported its promising safety profile. We also attempted to identify a plausible mechanism of action of compound 5 by applying both binding and functional in vitro studies. Overall, the data obtained for this lead molecule justifies the more comprehensive preclinical development of compound 5 as a candidate for a potentially broad-spectrum and safe anticonvulsant.

Comparative study on ABCB1-dependent efflux of anthracyclines and their metabolites: consequences for cancer resistance.

1. ABCB1 (P-glycoprotein, MDR1) is one of the most important transporter involved in cancer multi-drug resistance. It also plays a significant role in cancer resistance against anthracyclines, an anticancer group of drugs, including doxorubicin and daunorubicin. Several intracellular enzymes metabolise anthracyclines to carbonyl-reduced, hydroxy metabolites, which have impaired cytotoxic properties. However, metabolite efflux by ABCB1 transporter is not well characterised, while it may be the mechanism responsible for the metabolites' lack of activity.2. In this study recombinant ABCB1 ATPase transporter assay; anthracyclines accumulation assay in resistant cells overexpressing ABCB1; and molecular modelling were used to investigate anthracyclines: doxorubicin and daunorubicin and their carbonyl-reduced metabolites (doxorubicinol, daunorubicinol) susceptibility for ABCB1-dependent efflux.3. Based on the kinetics parameters of ATPase activity of ABCB1, it was found that daunorubicinol exerted an exceptionally high potential for being effluxed by the ABCB1 transporter. ABCB1 significantly affected the accumulation pattern of studied chemicals in resistant cancer cells. Doxorubicin and daunorubicinol accumulation were influenced by the activity of ABCB1 modulator - valspodar.4. Results indicate that ABCB1 activity affects not only anthracyclines but also their metabolites. Therefore crosstalk between the process of anthracyclines metabolism and metabolite efflux may be the mechanism of impairing anticancer properties of anthracyclines metabolites.

In Silico and In Vitro Assessment of Carbonyl Reductase 1 Inhibition Using ASP9521-A Potent Aldo-Keto Reductase 1C3 Inhibitor with the Potential to Support Anticancer Therapy Using Anthracycline Antibiotics.

Anthracycline antibiotics (ANT) are among the most widely used anticancer drugs. Unfortunately, their use is limited due to the development of drug resistance and cardiotoxicity. ANT metabolism, performed mainly by two enzymes-aldo-keto reductase 1C3 (AKR1C3) and carbonyl reductase 1 (CBR1)-is one of the proposed mechanisms generated by the described effects. In this study, we evaluated the CBR1 inhibitory properties of ASP9521, a compound already known as potent AKR1C3 inhibitor. First, we assessed the possibility of ASP9521 binding to the CBR1 catalytic site using molecular docking and molecular dynamics. The research revealed a potential binding mode of ASP9521. Moderate inhibitory activity against CBR1 was observed in studies with recombinant enzymes. Finally, we examined whether ASP9521 can improve the cytotoxic activity of daunorubicin against human lung carcinoma cell line A549 and assessed the cardioprotective properties of ASP9521 in a rat cardiomyocytes model (H9c2) against doxorubicin- and daunorubicin-induced toxicity. The addition of ASP9521 ameliorated the cytotoxic activity of daunorubicin and protected rat cardiomyocytes from the cytotoxic effect of both applied drugs. Considering the favorable bioavailability and safety profile of ASP9521, the obtained results encourage further research. Inhibition of both AKR1C3 and CBR1 may be a promising method of overcoming ANT resistance and cardiotoxicity.

In silico and in vitro ADME-Tox analysis and in vivo pharmacokinetic study of representative pan-PDE inhibitors from the group of 7,8-disubstituted derivatives of 1,3-dimethyl-7H-purine-2,6-dione.

Phosphodiesterase (PDE) inhibitors represent a wide class of chemically different compounds that have been extensively studied in recent years. Their anti-inflammatory and anti-fibrotic effects are particularly desirable in the treatment of chronic respiratory diseases, including asthma and chronic obstructive pulmonary disease (COPD). Due to diversified expression of individual PDEs within cells and/or tissues as well as PDE signaling compartmentalization, pan-PDE inhibitors (compounds capable of simultaneously blocking various PDE subtypes) are of particular interest. Recently, a large group of 7,8-disubstituted derivatives of 1,3-dimethyl-7H-purine-2,6-dione (theophylline) was designed and synthesized. These compounds were characterized as potent pan-PDE inhibitors and their prominent anti-inflammatory and anti-fibrotic activity in vitro has been proved. Herein, we investigated a general in vitro safety profile and pharmacokinetic characteristics of two leading compounds from this group: a representative compound with N'-benzylidenebutanehydrazide moiety (38) and a representative derivative containing N-phenylbutanamide fragment (145). Both tested pan-PDE inhibitors revealed no cytotoxic, mutagenic, and genotoxic activity in vitro, showed moderate metabolic stability in mouse and human liver microsomes, as well as fell into the low or medium permeation category. Additionally, 38 and 145 revealed a lack of interaction with adenosine receptors, including A1, A2A, and A2B. Pharmacokinetic analysis revealed that both tested 7,8-disubstituted derivatives of 1,3-dimethyl-7H-purine-2,6-dione were effectively absorbed from the peritoneal cavity. Simultaneously, they were extensively distributed to mouse lungs and after intraperitoneal (i.p.) administration were detected in bronchoalveolar lavage fluid. These findings provide evidence that investigated compounds represent a new drug candidates with a favorable in vitro safety profile and satisfactory pharmacokinetic properties after a single i.p. administration. As the next step, further pharmacokinetic studies after multiple i.p. and p.o. doses will be conducted to ensure effective 38 and 145 serum and lung concentrations for a longer period of time. In summary, 7,8-disubstituted derivatives of 1,3-dimethyl-7H-purine-2,6-dione represent a promising compounds worth testing in animal models of chronic respiratory diseases, the etiology of which involves various PDE subtypes.

Evaluation of Two Novel Hydantoin Derivatives Using Reconstructed Human Skin Model EpiskinTM: Perspectives for Application as Potential Sunscreen Agents.

This study aimed to assess two novel 5-arylideneimidazolidine-2,4-dione (hydantoin) derivatives (JH3 and JH10) demonstrating photoprotective activity using the reconstructed human skin model EpiskinTM. The skin permeability, irritation, and phototoxicity of the compounds was evaluated in vitro. Moreover, the in vitro genotoxicity and human metabolism of both compounds was studied. For skin permeation and irritation experiments, the test compounds were incorporated into a formulation. It was shown that JH3 and JH10 display no skin irritation and no phototoxicity. Both compounds did not markedly enhance the frequency of micronuclei in CHO-K1 cells in the micronucleus assay. Preliminary in vitro studies with liver microsomes demonstrated that hydrolysis appears to constitute their important metabolic pathway. EpiskinTM permeability experiments showed that JH3 permeability was lower than or close to currently used UV filters, whereas JH10 had the potential to permeate the skin. Therefore, a restriction of this compound permeability should be obtained by choosing the right vehicle or by optimizing it, which should be addressed in future studies.

Autophagy modulating agents as chemosensitizers for cisplatin therapy in cancer.

Although cisplatin is one of the most common antineoplastic drug, its successful utilisation in cancer treatment is limited by the drug resistance. Multiple attempts have been made to find potential cisplatin chemosensitisers which would overcome cancer cells resistance thus improving antineoplastic efficacy. Autophagy modulation has become an important area of interest regarding the aforementioned topic. Autophagy is a highly conservative cellular self-digestive process implicated in response to multiple environmental stressors. The high basal level of autophagy is a common phenomenon in cisplatin-resistant cancer cells which is thought to grant survival benefit. However current evidence supports the role of autophagy in either promoting or limiting carcinogenesis depending on the context. This encourages the search of substances modulating the process to alleviate cisplatin resistance. Such a strategy encompasses not only simple autophagy inhibition but also harnessing the process to induce autophagy-dependent cell death. In this paper, we briefly describe the mechanism of cisplatin resistance with a special emphasis on autophagy and we give an extensive literature review of potential substances with cisplatin chemosensitising properties related to autophagy modulation.

Synthesis and in vitro evaluation of anti-inflammatory, antioxidant, and anti-fibrotic effects of new 8-aminopurine-2,6-dione-based phosphodiesterase inhibitors as promising anti-asthmatic agents.

Phosphodiesterase (PDE) inhibitors are currently an extensively studied group of compounds that can bring many benefits in the treatment of various inflammatory and fibrotic diseases, including asthma. Herein, we describe a series of novel N'-phenyl- or N'-benzylbutanamide and N'-arylidenebutanehydrazide derivatives of 8-aminopurine-2,6-dione (27-43) and characterized them as prominent pan-PDE inhibitors. Most of the compounds exhibited antioxidant and anti-inflammatory activity in lipopolysaccharide (LPS)-induced murine macrophages RAW264.7. The most active compounds (32-35 and 38) were evaluated in human bronchial epithelial cells (HBECs) derived from asthmatics. To better map the bronchial microenvironment in asthma, HBECs after exposure to selected 8-aminopurine-2,6-dione derivatives were incubated in the presence of two proinflammatory and/or profibrotic factors: transforming growth factor type ß (TGF-ß) and interleukin 13 (IL-13). Compounds 32-35 and 38 significantly reduced both IL-13- and TGF-ß-induced expression of proinflammatory and profibrotic mediators, respectively. Detailed analysis of their inhibition preferences for selected PDEs showed high affinity for isoenzymes important in the pathogenesis of asthma, including PDE1, PDE3, PDE4, PDE7, and PDE8. The presented data confirm that structural modifications within the 7 and 8 positions of the purine-2,6-dione core result in obtaining preferable pan-PDE inhibitors which in turn exert an excellent anti-inflammatory and anti-fibrotic effect in the bronchial epithelial cells derived from asthmatic patients. This dual-acting pan-PDE inhibitors constitute interesting and promising lead structures for further anti-asthmatic agent discovery.

Cinnamic Acid Derivatives as Cardioprotective Agents against Oxidative and Structural Damage Induced by Doxorubicin.

Doxorubicin (DOX) is a widely used anticancer drug. However, its clinical use is severely limited due to drug-induced cumulative cardiotoxicity, which leads to progressive cardiomyocyte dysfunction and heart failure. Enormous efforts have been made to identify potential strategies to alleviate DOX-induced cardiotoxicity; however, to date, no universal and highly effective therapy has been introduced. Here we reported that cinnamic acid (CA) derivatives exert a multitarget protective effect against DOX-induced cardiotoxicity. The experiments were performed on rat cardiomyocytes (H9c2) and human induced-pluripotent-stem-cell-derived cardiomyocytes (hiPSC-CMs) as a well-established model for cardiac toxicity assessment. CA derivatives protected cardiomyocytes by ameliorating DOX-induced oxidative stress and viability reduction. Our data indicated that they attenuated the chemotherapeutic's toxicity by downregulating levels of caspase-3 and -7. Pre-incubation of cardiomyocytes with CA derivatives prevented DOX-induced motility inhibition in a wound-healing assay and limited cytoskeleton rearrangement. Detailed safety analyses-including hepatotoxicity, mutagenic potential, and interaction with the hERG channel-were performed for the most promising compounds. We concluded that CA derivatives show a multidirectional protective effect against DOX-induced cardiotoxicity. The results should encourage further research to elucidate the exact molecular mechanism of the compounds' activity. The lead structure of the analyzed CA derivatives may serve as a starting point for the development of novel therapeutics to support patients undergoing DOX therapy.

Anticonvulsant and analgesic in neuropathic pain activity in a group of new aminoalkanol derivatives.

As part of the presented research, thirteen new aminoalkanol derivatives were designed and obtained by chemical synthesis. In vivo studies (mice, i.p.) showed anticonvulsant activity (MES) of nine compounds, and in the case of one compound (R,S-trans-2-((2-(2,3,5-trimethylphenoxy)ethyl)amino)cyclohexan-1-ol, 4) both anticonvulsant (ED50 MES = 15.67 mg/kg, TD50 rotarod = 78.30 mg.kg, PI = 5.00) and analgesic activity (OXA-induced neuropathic pain, active at 15 mg/kg). For selected active compounds additional in vitro studies have been performed, including receptor studies (5-HT1A), evaluation of antioxidant activity (DPPH assay), metabolism studies as well as safety panel (mutagenicity, safety in relation to the gastrointestinal flora, cytotoxicity towards astrocytes as well as impact on their proliferation and cell cycle).

The Involvement of Xanthone and (E)-Cinnamoyl Chromophores for the Design and Synthesis of Novel Sunscreening Agents.

Excessive UV exposure contributes to several pathological conditions like skin burns, erythema, premature skin aging, photodermatoses, immunosuppression, and skin carcinogenesis. Effective protection from UV radiation may be achieved with the use of sunscreens containing UV filters. Currently used UV filters are characterized by some limitations including systemic absorption, endocrine disruption, skin allergy induction, and cytotoxicity. In the research centers all over the world new molecules are developed to improve the safety, photostability, solubility, and absorption profile of new derivatives. In our study, we designed and synthesized seventeen novel molecules by combining in the structures two chromophores: xanthone and (E)-cinnamoyl moiety. The ultraviolet spectroscopic properties of the tested compounds were confirmed in chloroform solutions. They acted as UVB or UVA/UVB absorbers. The most promising compound 9 (6-methoxy-9-oxo-9H-xanthen-2-yl)methyl (E)-3-(2,4-dimethoxyphenyl)acrylate) absorbed UV radiation in the range 290-369 nm. Its photoprotective activity and functional photostability were further evaluated after wet milling and incorporation in the cream base. This tested formulation with compound 9 possessed very beneficial UV protection parameters (SPFin vitro of 19.69 ± 0.46 and UVA PF of 12.64 ± 0.32) which were similar as broad-spectrum UV filter tris-biphenyl triazine. Additionally, compound 9 was characterized by high values of critical wavelength (381 nm) and UVA/UVB ratio (0.830) thus it was a good candidate for broad-spectrum UV filter and it might protect skin against UVA-induced photoaging. Compound 9 were also shown to be photostable, non-cytotoxic at concentrations up to 50 µM when tested on five cell lines, and non-mutagenic in Ames test. It also possessed no estrogenic activity, according to the results of MCF-7 breast cancer model. Additionally, its favorable lipophilicity (miLogP = 5.62) does not predispose it to penetrate across the skin after topical application.

S(+)-(2E)-N-(2-Hydroxypropyl)-3-Phenylprop-2-Enamide (KM-568): A Novel Cinnamamide Derivative with Anticonvulsant Activity in Animal Models of Seizures and Epilepsy.

Epilepsy is one of the most frequent neurological disorders affecting about 1% of the world's human population. Despite availability of multiple treatment options including antiseizure drugs, it is estimated that about 30% of seizures still remain resistant to pharmacotherapy. Searching for new antiseizure and antiepileptic agents constitutes an important issue within modern medicinal chemistry. Cinnamamide derivatives were identified in preclinical as well as clinical studies as important drug candidates for the treatment of epilepsy. The cinnamamide derivative presented here: S(+)-(2E)-N-(2-hydroxypropyl)-3-phenylprop-2-enamide (S(+)-N-(2-hydroxypropyl)cinnamamide, compound KM-568) showed anticonvulsant activity in several models of epilepsy and seizures in mice and rats. It was active in a genetic animal model of epilepsy (Frings audiogenic seizure-susceptible mouse model, ED50 = 13.21 mg/kg, i.p.), acute seizures induced electrically (maximal electroshock test ED50 = 44.46 mg/kg mice i.p., ED50 = 86.6 mg/kg mice p.o., ED50 = 27.58 mg/kg rats i.p., ED50 = 30.81 mg/kg rats p.o., 6-Hz psychomotor seizure model 32 mA ED50 = 71.55 mg/kg mice i.p., 44 mA ED50 = 114.4 mg/kg mice i.p.), chronic seizures induced electrically (corneal kindled mouse model ED50 = 79.17 mg/kg i.p., hippocampal kindled rat model ED50 = 24.21 mg/kg i.p., lamotrigine-resistant amygdala kindled seizure model in rats ED50 = 58.59 mg/kg i.p.), acute seizures induced chemically (subcutaneous metrazol seizure threshold test ED50 = 104.29 mg/kg mice i.p., ED50 = 107.27 mg/kg mice p.o., ED50 = 41.72 mg/kg rats i.p., seizures induced by picrotoxin in mice ED50 = 94.11 mg/kg i.p.) and the pilocarpine-induced status epilepticus model in rats (ED50 = 279.45 mg/kg i.p., ED97 = 498.2 mg/kg i.p.). The chemical structure of the compound including configuration of the chiral center was confirmed by NMR spectroscopy, LC/MS spectroscopy, elemental analysis, and crystallography. Compound KM-568 was identified as a moderately stable derivative in an in vitro mouse liver microsome system. According to the Ames microplate format mutagenicity assay performed, KM-568 was not a base substitution or frameshift mutagen. Cytotoxicity evaluation in two cell lines (HepG2 and H9c2) proved the safety of the compound in concentrations up to 100 µM. Based on the results of anticonvulsant activity and safety profile, S(+)-(2E)-N-(2-hydroxypropyl)-3-phenylprop-2-enamide could be proposed as a new lead compound for further preclinical studies on novel treatment options for epilepsy.

A Novel, Pan-PDE Inhibitor Exerts Anti-Fibrotic Effects in Human Lung Fibroblasts via Inhibition of TGF-ß Signaling and Activation of cAMP/PKA Signaling.

Phosphodiesterase (PDE) inhibitors are currently a widespread and extensively studied group of anti-inflammatory and anti-fibrotic compounds which may find use in the treatment of numerous lung diseases, including asthma and chronic obstructive pulmonary disease. Several PDE inhibitors are currently in clinical development, and some of them, e.g., roflumilast, are already recommended for clinical use. Due to numerous reports indicating that elevated intracellular cAMP levels may contribute to the alleviation of inflammation and airway fibrosis, new and effective PDE inhibitors are constantly being sought. Recently, a group of 7,8-disubstituted purine-2,6-dione derivatives, representing a novel and prominent pan-PDE inhibitors has been synthesized. Some of them were reported to modulate transient receptor potential ankyrin 1 (TRPA1) ion channels as well. In this study, we investigated the effect of selected derivatives (832-a pan-PDE inhibitor, 869-a TRPA1 modulator, and 145-a pan-PDE inhibitor and a weak TRPA1 modulator) on cellular responses related to airway remodeling using MRC-5 human lung fibroblasts. Compound 145 exerted the most considerable effect in limiting fibroblast to myofibroblasts transition (FMT) as well as proliferation, migration, and contraction. The effect of this compound appeared to depend mainly on its strong PDE inhibitory properties, and not on its effects on TRPA1 modulation. The strong anti-remodeling effects of 145 required activation of the cAMP/protein kinase A (PKA)/cAMP response element-binding protein (CREB) pathway leading to inhibition of transforming growth factor type ß1 (TGF-ß1) and Smad-dependent signaling in MRC-5 cells. These data suggest that the TGF-ß pathway is a major target for PDE inhibitors leading to inhibitory effects on cell responses involved in airway remodeling. These potent, pan-PDE inhibitors from the group of 7,8-disubstituted purine-2,6-dione derivatives, thus represent promising anti-remodeling drug candidates for further research.

Aclarubicin: contemporary insights into its mechanism of action, toxicity, pharmacokinetics, and clinical standing.

Aclarubicin (aclacinomycin A) is one of the anthracycline antineoplastic antibiotics with a multifaceted mechanism of antitumor activity. As a second-generation drug, it offers several advantages compared to standard anthracycline drugs such as doxorubicin or daunorubicin, which could position it as a potential blockbuster drug in antitumor therapy. Key mechanisms of action for aclarubicin include the inhibition of both types of topoisomerases, suppression of tumor invasion processes, generation of reactive oxygen species, inhibition of chymotrypsin-like activity, influence on cisplatin degradation, and inhibition of angiogenesis. Therefore, aclarubicin appears to be an ideal candidate for antitumor therapy. However, despite initial interest in its clinical applications, only a limited number of high-quality trials have been conducted thus far. Aclarubicin has primarily been evaluated as an induction therapy in acute myeloid and lymphoblastic leukemia. Studies have indicated that aclarubicin may hold significant promise for combination therapies with other anticancer drugs, although further research is needed to confirm its potential. This paper provides an in-depth exploration of aclarubicin's diverse mechanisms of action, its pharmacokinetics, potential toxicity, and the clinical trials in which it has been investigated.

Improving Activity of New Arylurea Agents against Multidrug-Resistant and Biofilm-Producing Staphylococcus epidermidis.

Multidrug-resistant (MDR) strains of Staphylococcus epidermidis (S. epidermidis), prevalent in hospital environments, contribute to increased morbidity and mortality, especially among newborns, posing a critical concern for neonatal sepsis. In response to the pressing demand for novel antibacterial therapies, we present findings from synthetic chemistry and structure-activity relationship studies focused on arylsulfonamide/arylurea derivatives of aryloxy[1-(thien-2-yl)propyl]piperidines. Through bioisosteric replacement of the sulfonamide fragment with a urea moiety, compound 25 was identified, demonstrating potent bacteriostatic activity against clinical multidrug-resistant S. epidermidis strains (MIC50 and MIC90 = 1.6 and 3.125 µg/mL). Importantly, it showed activity against linezolid-resistant strains and exhibited selectivity over mammalian cells. Compound 25 displayed antibiofilm-forming properties against clinical S. epidermidis strains and demonstrated the capacity to eliminate existing biofilm layers. Additionally, it induced complete depolarization of the bacterial membrane in clinical S. epidermidis strains. In light of these findings, targeting bacterial cell membranes with compound 25 emerges as a promising strategy in the fight against multidrug-resistant S. epidermidis strains.

5-HT6 receptor neutral antagonists protect astrocytes: A lesson from 2-phenylpyrrole derivatives.

The serotonin type 6 receptor (5-HT6R) displays a strong constitutive activity, suggesting it participates largely in the physiological and pathological processes controlled by the receptor. The active states of 5-HT6R engage particular signal transduction pathways that lead to different biological responses. In this study, we present the development of 5-HT6R neutral antagonists at Gs signaling built upon the 2-phenylpyrrole scaffold. Using molecular dynamics simulations, we outline the relationship between the exposure of the basic center of the molecules and their ability to target the agonist-activated state of the receptor. Our study identifies compound 30 as a potent and selective neutral antagonist at 5-HT6R-operated Gs signaling. Furthermore, we demonstrate the cytoprotective effects of 30 and structurally diverse 5-HT6R neutral antagonists at Gs signaling in C8-D1A cells and human astrocytes exposed to rotenone. This effect is not observed for 5-HT6R agonists or inverse agonists. In light of these findings, we propose compound 30 as a valuable molecular probe to study the biological effects associated with the agonist-activated state of 5-HT6R and provide insight into the glioprotective properties of 5-HT6R neutral antagonists at Gs signaling.

Antidepressant pharmaceuticals in aquatic systems, individual-level ecotoxicological effects: growth, survival and behavior.

The growing consumption of antidepressant pharmaceuticals has resulted in their widespread occurrence in the environment, particularly in waterways with a typical concentration range from ng L-1 to µg L-1. An increasing number of studies have confirmed the ecotoxic potency of antidepressants, not only at high concentrations but also at environmentally relevant levels. The present review covers literature from the last decade on the individual-level ecotoxicological effects of the most commonly used antidepressants, including their impact on behavior, growth, and survival. We focus on the relationship between antidepressants physico-chemical properties and dynamics in the environment. Furthermore, we discuss the advantages of considering behavioral changes as sensitive endpoints in ecotoxicology, as well as some current methodological shortcomings in the field, including low standardization, reproducibility and context-dependency.

In silico and in vitro evaluation of a safety profile of a cosmetic ingredient: 4-methoxychalcone (4-MC).

Chalcone is an important scaffold within medicinal and cosmetic chemistry. The structure enables multiple modifications which may result in obtaining compounds with desirable bioactivity. One of the chalcone derivatives, 4-methoxychalcone is a known cosmetic ingredient indexed in Cosing database as an antioxidant, bleaching, and skin conditioning substance. We investigated its in silico and in vitro safety profile. In silico study using Derek Nexus showed its potential of skin sensitisation, equivocal nature of chromosome damage in vitro in mammals, but also no mutagenic properties. In vitro research proved its activity as melanogenesis inhibitor in B16F10 cell line at the doses 12.5-3.125 µM. Evaluations performed in various cell lines showed that the cytotoxic doses were 50-25 µM. Tests in Episkin™ proved its ability to penetrate across epidermis and enabled classification of 2% formulation in PEG as non-irritant. In micronucleus tests it showed no genotoxicity. Studies in Cunninghamella echinulata model proved that 4-methoxychalcone was metabolised to less lipophilic products. 4-methoxychalcone showed phototoxic potential, its EC50(+UV) = 3.57 µg/mL, PIF = 10.19 and MPE = 0.428 were comparable to chlorpromazine. Moreover, 4-methoxychalcone showed ecotoxic potential in Microtox® assay with EC50(5 min) = 0.0047 mg/L and EC50(15 min) = 0.0033 mg/L. Although active doses were lower than toxic ones, some potential safety risks were noticed. Especially, due to the phototoxicity potential of 4-methoxychalcone, its use as depigmenting agent should involve avoidance of sunlight and use of appropriate photoprotection.

Saponin Fraction CIL1 from Lysimachia ciliata L. Enhances the Effect of a Targeted Toxin on Cancer Cells.

Saponins are plant metabolites that possess multidirectional biological activities, among these is antitumor potential. The mechanisms of anticancer activity of saponins are very complex and depend on various factors, including the chemical structure of saponins and the type of cell they target. The ability of saponins to enhance the efficacy of various chemotherapeutics has opened new perspectives for using them in combined anticancer chemotherapy. Co-administration of saponins with targeted toxins makes it possible to reduce the dose of the toxin and thus limit the side effects of overall therapy by mediating endosomal escape. Our study indicates that the saponin fraction CIL1 of Lysimachia ciliata L. can improve the efficacy of the EGFR-targeted toxin dianthin (DE). We investigated the effect of cotreatment with CIL1 + DE on cell viability in a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, on proliferation in a crystal violet assay (CV) and on pro-apoptotic activity using Annexin V/7 Actinomycin D (7-AAD) staining and luminescence detection of caspase levels. Cotreatment with CIL1 + DE enhanced the target cell-specific cytotoxicity, as well as the antiproliferative and proapoptotic properties. We found a 2200-fold increase in both the cytotoxic and antiproliferative efficacy of CIL1 + DE against HER14-targeted cells, while the effect on control NIH3T3 off-target cells was less profound (6.9- or 5.4-fold, respectively). Furthermore, we demonstrated that the CIL1 saponin fraction has a satisfactory in vitro safety profile with a lack of cytotoxic and mutagenic potential.

Inhaled pan-phosphodiesterase inhibitors ameliorate ovalbumin-induced airway inflammation and remodeling in murine model of allergic asthma.

Asthma is a heterogeneous, chronic respiratory disease characterized by airway inflammation and remodeling. Phosphodiesterase (PDE) inhibitors represent one of the intensively studied groups of potential anti-asthmatic agents due to their affecting both airway inflammation and remodeling. However, the effect of inhaled pan-PDE inhibitors on allergen induced asthma has not been reported to date. In this study we investigated the impact of two, representative strong pan-PDE inhibitors from the group of 7,8-disubstituted derivatives of 1,3-dimethyl-3,7-dihydro-1H-purine-2,6-dione: compound 38 and 145, on airway inflammation and remodeling in murine model of ovalbumin (OVA)-challenged allergic asthma. Female Balb/c mice were sensitized and challenged with OVA, 38 and 145 were administrated by inhalation, before each OVA challenge. The inhaled pan-PDE inhibitors markedly reduced the OVA-induced airway inflammatory cell infiltration, eosinophil recruitment, Th2 cytokine level in bronchoalveolar lavage fluid, as well as both, total and OVA-specific IgE levels in plasma. In addition, inhaled 38 and 145 decreased many typical features of airway remodeling, including goblet cell metaplasia, mucus hypersecretion, collagen overproduction and deposition, as well as Tgfb1, VEGF, and α-SMA expression in airways of allergen challenged mice. We also demonstrated that both 38 and 145 alleviate airway inflammation and remodelling by inhibition of the TGF-ß/Smad signaling pathway activated in OVA-challenged mice. Taken together, these results suggest that the investigated pan-PDE inhibitors administered by inhalation are dual acting agents targeting both airway inflammation and remodeling in OVA-challenged allergic asthma and may represent promising, anti-asthmatic drug candidates.