Description of Druglike Properties of Safranal and Its Chemistry behind Low Oral Exposure

Development of di-arylated 1,2,4-triazole-based derivatives as therapeutic agents against breast cancer: synthesis and biological evaluation

The synthesis, anticancer activity, and metabolic stability of di-arylated 1,2,4-triazole molecules have been reported. Utilizing an efficient programmed arylation technique which starts from commercially available 3-bromo-1H-1,2,4-triazole, a series of therapeutic agents have been synthesized and screened against three human breast cancer cell lines, MDA-MB-231, MCF-7, and ZR-75-1, via an in vitro growth inhibition assay. At 10 μM concentration, 4k, 4m, 4q, and 4t have displayed good anticancer potency in the MCF-7 cell line, among which 4q has shown the best efficacy (IC50 = 4.8 μM). Mechanistic investigations of 4q have indicated the elevation of the pro-apoptotic BAX protein in the malignant cells along with mitochondrial outer membrane permeabilization which are hallmarks of apoptosis. Further metabolic stability studies in diverse liver microsomes have provided insights into the favorable pharmacokinetic properties of 4q in humans, establishing it as a promising lead compound of this series that deserves further investigation.

ADME/PK Insights of Crocetin: A Molecule Having an Unusual Chemical Structure with Druglike Features

Crocetin is a promising phyto-based molecule to treat Alzheimer's disease (AD). The chemical structure of crocetin is incongruent with various standard structural features of CNS drugs. As poor pharmacokinetic behavior is the major hurdle for any candidate to become a drug, we elucidated its druggable characteristics by implementing in silico, in vitro, and in vivo approaches, as limited ADME/PK information is available. Results demonstrate several attributes of crocetin based on rules of drug-likeness, lipophilicity, pKa, P-gp inhibitory activity, plasma stability, RBC partitioning, metabolic stability, CYP inhibitory action, blood-brain barrier (BBB) permeability, oral bioavailability, and pharmacokinetic interaction with marketed anti-Alzheimer's drugs (memantine, donepezil, galantamine, and rivastigmine). However, aqueous solubility, chemical stability, plasma protein binding, and P-gp induction are some concerns associated with this molecule that should be taken into consideration during its further development. Overall results indicate favorable ADME/PK behavior and potential druggable candidature of crocetin.

Cannabidiol-Based Prodrugs: Synthesis and Bioevaluation

Cannabidiol (CBD 1) is a nonpsychotic cannabinoid-based drug approved by the U.S. FDA for treating refractory epilepsy, namely, Lennox-Gastaut and Dravet syndrome. However, its low aqueous solubility and oral bioavailability are compensated by administering high doses, and there is an increased demand for conjugates with improved properties. In this direction, the present work is focused on synthesizing CBD-based prodrugs to address the issue of poor solubility and oral bioavailability. Several CBD-based prodrugs were synthesized and studied in a battery of assays: viz, release kinetic (ex vivo), solubility (in vitro), chemical stability (in vitro), plasma stability (ex vivo), pharmacokinetics (in vivo), and efficacy studies (in vivo). Among the synthesized prodrugs, the morpholinyl CBD-based prodrugs 3a and 3aa showed good release behavior, stability, better solubility, and a plasma profile. Moreover, prodrug candidate 3aa showed better therapeutic efficacy. The present study identifies CBD-based prodrugs with improved physiochemical properties and oral exposure.

Sila-CBD Derivatives as Inhibitors of Heme-Induced NLRP3 Inflammasome: Application in Hemolytic Diseases

Synthesis and biological evaluation of silicon-incorporated phytocannabinoids with improved pharmacological properties toward inflammatory diseases are described. The synthesized sila-analogues 15a, 15b, and 15c displayed potent inhibition of pro-inflammatory cytokines, including IL-1β, TNF-α, and IL-6 at 10 μM. Further, the release of heme during the lysis of red blood cells in hemolytic diseases is one of the major reasons for inflammation associated with the pathophysiology of these diseases. Due to scanty literature related to inhibitors of heme-mediated induction of the NLRP3 inflammasome, we decided to test these compounds against it. Compounds 15a and 15c significantly inhibited the heme-mediated induction of the NLRP3 inflammasome at a concentration of 0.1 μM. Interestingly, the sila-CBD derivatives also showed higher metabolic stability in contrast to their carbon analogues. Anti-NLRP3 inflammasome activity of compounds 15a and 15c were further validated in vivo against heme-mediated peritoneal inflammation. The anti-inflammatory activity of these compounds could be useful in treating diseases such as sickle cell anemia and thalassemia involving the hemolysis-mediated activation of the NLRP3 inflammasome.

Impact of Disease States on the Oral Pharmacokinetics of EIDD-1931 (an Active Form of Molnupiravir) in Rats for Implication in the Dose Adjustment

The pharmacokinetic alteration of an antimicrobial medication leading to sub-therapeutic plasma level can aid in the emergence of resistance, a global threat nowadays. In this context, molnupiravir (prodrug of EIDD-1931) is the most efficacious orally against corona virus disease (COVID-19). In addition to drug-drug interaction, the pharmacokinetics of a drug can significantly vary during any disease state, leading to disease-drug interaction. However, no information is available for such a recently approved drug. Therefore, we aimed to explore the oral pharmacokinetics of EIDD-1931 in seven chemically induced disease states individually compared to the normal state using various rat models. Induction of any disease situation was confirmed by the disease specific study(s) prior to pharmacokinetic investigations. Compared to the normal state, substantially lowered plasma exposure (0.47- and 0.63-fold) with notably enhanced clearance (2.00- and 1.56-fold) of EIDD-1931 was observed in rats of ethanol-induced gastric injury and carbon tetrachloride-induced liver injury states. Conversely, paclitaxel-induced neuropathic pain and cisplatin-induced kidney injury states exhibited opposite outcomes on oral exposure (1.43- and 1.50-fold) and clearance (0.69- and 0.65-fold) of EIDD-1931. Although the highest plasma concentration (2.26-fold) markedly augmented in the doxorubicin-induced cardiac injury state, streptozocin-induced diabetes and lipopolysaccharide-induced lung injury state did not substantially influence the pharmacokinetics of EIDD-1931. Exploring the possible phenomenon behind the reduced or boosted plasma exposure of EIDD-1931, results suggest the need for dose adjustment in respective diseased conditions in order to achieve desired efficacy during oral therapy of EIDD-1931.

Design, Synthesis, and Pharmacological Evaluation of Embelin-Aryl/alkyl Amine Hybrids as Orally Bioavailable Blood-Brain Barrier Permeable Multitargeted Agents with Therapeutic Potential in Alzheimer's Disease: Discovery of SB-1448

The complex and multifaceted nature of Alzheimer's disease has brought about a pressing demand to develop ligands targeting multiple pathways to combat its outrageous prevalence. Embelin is a major secondary metabolite of Embelia ribes Burm f., one of the oldest herbs in Indian traditional medicine. It is a micromolar inhibitor of cholinesterases (ChEs) and β-site amyloid precursor protein cleaving enzyme 1 (BACE-1) with poor absorption, distribution, metabolism, and excretion (ADME) properties. Herein, we synthesize a series of embelin-aryl/alkyl amine hybrids to improve its physicochemical properties and therapeutic potency against targeted enzymes. The most active derivative, 9j (SB-1448), inhibits human acetylcholinesterase (hAChE), human butyrylcholinesterase (hBChE), and human BACE-1 (hBACE-1) with IC₅₀ values of 0.15, 1.6, and 0.6 μM, respectively. It inhibits both ChEs noncompetitively with k_i values of 0.21 and 1.3 μM, respectively. It is orally bioavailable, crosses blood-brain barrier (BBB), inhibits Aβ self-aggregation, possesses good ADME properties, and protects neuronal cells from scopolamine-induced cell death. The oral administration of 9j at 30 mg/kg attenuates the scopolamine-induced cognitive impairments in C57BL/6J mice.

Multitargeted C9-substituted ester and ether derivatives of berberrubine for Alzheimer's disease: Design, synthesis, biological evaluation, metabolic stability, and pharmacokinetics

Berberrubine is a naturally occurring isoquinoline alkaloid and a bioactive metabolite of berberine. Berberine exhibits a wide range of pharmacological activities, including cholinesterase inhibition. The cholinesterase inhibitors provide symptomatic treatment for Alzheimer's disease; however, multitarget-directed ligands have the potential as disease-modifying therapeutics. Herein, we prepared a series of C9-substituted berberrubine derivatives intending to discover dual cholinesterase and beta-site amyloid-precursor protein cleaving enzyme 1 (BACE-1) inhibitors. Most synthesized derivatives possessed balanced dual inhibition (AChE and BChE) activity in the submicromolar range and a moderate inhibition against BACE-1. Two most active ester derivatives, 12a and 11d, display inhibition of AChE, BChE, and BACE-1. The 3-methoxybenzoyl ester derivative, 12a, inhibits electric eel acetylcholinesterase (EeAChE), equine serum butyrylcholinesterase (eqBChE), and human hBACE-1 with IC₅₀ values of 0.5, 4.3, and 11.9 μM, respectively and excellent BBB permeability (P_e  = 8 × 10^-6  cm/s). The ester derivative 12a is metabolically unstable; however, its ether analog 13 is stable in HLM and exhibits inhibition of AChE, BChE, and BACE-1 with IC₅₀ values of 0.44, 3.8, and 17.9 μM, respectively. The ether analog also inhibits self-aggregation of Aβ and crosses BBB (P_e  = 7.3 × 10^-6  cm/s). Administration of 13 at 5 mg/kg (iv) in Wistar rats showed excellent plasma exposure with AUC_0-∞ of 28,834 ng min/ml. In conclusion, the multitargeted berberrubine ether derivative 13 is CNS permeable and has good ADME properties.

Mineral Content and Volatile Profiling of Prunus avium L. (Sweet Cherry) By-Products from Fundão Region (Portugal)

Large amounts of Prunus avium L. by-products result from sweet cherry production and processing. This work aimed to evaluate the mineral content and volatile profiling of the cherry stems, leaves, and flowers of the Saco cultivar collected from the Fundão region (Portugal). A total of 18 minerals were determined by ICP-MS, namely 8 essential and 10 non-essential elements. Phosphorus (P) was the most abundant mineral, while lithium (Li) was detected in trace amounts. Three different preparations were used in this work to determine volatiles: hydroethanolic extracts, crude extracts, and aqueous infusions. A total of 117 volatile compounds were identified using HS-SPME/GC-MS, distributed among different chemical classes: 31 aldehydes, 14 alcohols, 16 ketones, 30 esters, 4 acids, 4 monoterpenes, 3 norisoprenoids, 4 hydrocarbons, 7 heterocyclics, 1 lactone, 1 phenol, and 2 phenylpropenes. Benzaldehyde, 4-methyl-benzaldehyde, hexanal, lilac aldehyde, and 6-methyl-5-hepten-2-one were the major volatile compounds. Differences in the types of volatiles and their respective amounts in the different extracts were found. This is the first study that describes the mineral and volatile composition of Portuguese sweet cherry by-products, demonstrating that they could have great potential as nutraceutical ingredients and natural flavoring agents to be used in the pharmaceutical, cosmetic, and food industries.

Pharmacokinetic Assessment of Rottlerin from Mallotus philippensis Using a Highly Sensitive Liquid Chromatography-Tandem Mass Spectrometry-Based Bioanalytical Method

Rottlerin is a key bioactive phytoconstituent present in the pericarp of Mallotus philippensis. It shows promising multifaceted pharmacological actions against cancer. However, there is hardly any report for the quantification of rottlerin in the biological matrix and on its pharmacokinetic behavior. Therefore, we aimed in the present study to assess selective in vitro ADME properties and in vivo pharmacokinetics of isolated and characterized rottlerin using a newly developed and validated liquid chromatography-tandem mass spectrometry-based highly sensitive bioanalytical method. The method was found to be simple (mobile phase and analytical column), sensitive (1.9 ng/mL), and rapid (run time of 2.5 min). All the validation parameters were within the acceptable criteria of the United States Food and Drug Administration's bioanalytical method validation guideline. The method was found to be very useful to assess lipophilicity, plasma stability, metabolic stability, plasma protein binding of rottlerin, as well as its oral and intravenous pharmacokinetics in mice. Rottlerin showed a number of drug-like pharmacokinetic properties (in vitro). Moreover, it displayed an excellent half-life (>2 h) and oral bioavailability (>35%) as compared to other members of natural phenolics. The present study is the first-time report of in vitro ADME properties and in vivo preclinical pharmacokinetics of rottlerin. The generated information is very much useful for its further development as a phytotherapeutics toward cancer therapy.

Antiarthritic activity of OA-DHZ; a gastroprotective NF-κB/MAPK/COX inhibitor

Arthritis, a primary autoimmune disorder having a global incidence of 2.03% person/year, is presently being treated by many commercially available drugs that treat symptomatically or improve the disease's clinical state; however, all the therapies pose varying amount of side effects. Therefore, it has become a fundamental need to search for therapeutics that offer better efficacy and safety profile, and the natural or nature-derived products are known for their outstanding performance in this arena. OA-DHZ, known to possess anti-inflammatory and analgesic properties, when explored for its efficacy against arthritis in adjuvant-induced arthritis (AIA) model, was found to inhibit paw edema by 34% and TNF-α, IL-6, and IL-1β by 67%, 39%, and 45% respectively when compared to diseased control. It was also able to reduce the inflamed spleen size by 45% and successfully normalized biochemical and hematological changes that followed arthritis. In vitro studies revealed that the underlying mechanism for inhibiting arthritis progression might be due to NF-κB /MAPK pathway modulation. OA-DHZ also showed selective inhibition of COX-2 in vitro while showing gastroprotective effects when evaluated for ulcerogenic and antiulcer potential in vivo. In contrast to the results obtained from in vivo experimentation, there is a disparity in the pharmacokinetic profile of OA-DHZ, where it showed low oral exposure and high clearance rate. OA-DHZ being antiarthritic acting via NF-κB /MAPK/ COX inhibition while showing gastroprotective effects, can be a suitable candidate to be in the drug pipeline and further exploration.

1,3-Cyclohexadien-1-Als: Synthesis, Reactivity and Bioactivities

In synthetic organic chemistry, there are very useful basic compounds known as building blocks. One of the main reactions wherein they are applied for the synthesis of complex molecules is the Diels-Alder cycloaddition. This reaction is between a diene and a dienophile. Among the most important dienes are the cyclic dienes, as they facilitate the reaction. This review considers the synthesis and reactivity of one of these dienes with special characteristics-it is cyclic and has an electron withdrawing group. This building block has been used for the synthesis of biologically active compounds and is present in natural compounds with interesting properties.

Potential Herb-Drug Interactions in the Management of Age-Related Cognitive Dysfunction

Late-life mild cognitive impairment and dementia represent a significant burden on healthcare systems and a unique challenge to medicine due to the currently limited treatment options. Plant phytochemicals have been considered in alternative, or complementary, prevention and treatment strategies. Herbals are consumed as such, or as food supplements, whose consumption has recently increased. However, these products are not exempt from adverse effects and pharmacological interactions, presenting a special risk in aged, polymedicated individuals. Understanding pharmacokinetic and pharmacodynamic interactions is warranted to avoid undesirable adverse drug reactions, which may result in unwanted side-effects or therapeutic failure. The present study reviews the potential interactions between selected bioactive compounds (170) used by seniors for cognitive enhancement and representative drugs of 10 pharmacotherapeutic classes commonly prescribed to the middle-aged adults, often multimorbid and polymedicated, to anticipate and prevent risks arising from their co-administration. A literature review was conducted to identify mutual targets affected (inhibition/induction/substrate), the frequency of which was taken as a measure of potential interaction. Although a limited number of drugs were studied, from this work, interaction with other drugs affecting the same targets may be anticipated and prevented, constituting a valuable tool for healthcare professionals in clinical practice.

Safranal protects against ischemia-induced PC12 cell injury through inhibiting oxidative stress and apoptosis

Safranal, isolated from saffron (Crocus sativus L.), is known to possesses neuroprotective effects. In this study, the neuroprotective potential of safranal against PC12 cell injury triggered by ischemia/reperfusion was investigated. PC12 cells were pretreated with safranal at concentration ranges of 10-160 μM for 2 h and then deprived from oxygen-glucose-serum for 6 h, followed by reoxygenation for 24 h (OGD condition). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), 2,7-dichlorofluorescin diacetate (DCF-DA), and comet assays were used to measure the extent of cellular viability, reactive oxygen substances (ROS), and DNA damage, respectively. Also, propidium iodide (PI) flow cytometry assay and western blotting of bax, bcl-2, and cleaved caspase-3 were performed for assessment of apoptosis. OGD exposure reduced the cell viability and increased intracellular ROS production, oxidative DNA damage, and apoptosis, in comparison with untreated control cells. Pretreatment with safranal (40 and 160 μM) significantly attenuated OGD-induced PC12 cell death, oxidative damage, and apoptosis. Furthermore, safranal markedly reduced the overexpression of bax/bcl-2 ratio and active caspase-3 following OGD (p < 0.05). The present findings indicated that safranal protects against OGD-induced neurotoxicity via modulating of oxidative and apoptotic responses.Graphical abstract The schematic representation of the mode of action of safranal against PC12 cells death induced by oxygen-glucose-serum deprivation and reoxygenation (OGD-R).

TMPE Derived from Saffron Natural Monoterpene as Cytotoxic and Multidrug Resistance Reversing Agent in Colon Cancer Cells

Terpenes constitute one of the largest groups of natural products. They exhibit a wide range of biological activities including antioxidant, anticancer, and drug resistance modulating properties. Saffron extract and its terpene constituents have been demonstrated to be cytotoxic against various types of cancer cells, including breast, liver, lung, pancreatic, and colorectal cancer. In the present work, we have studied anticancer properties of TMPE, a newly synthesized monoterpene derivative of β-cyclocitral—the main volatile produced by the stigmas of unripe crocuses. TMPE presented selective cytotoxic activity to doxorubicin-resistant colon cancer cells and was identified to be an effective MDR modulator in doxorubicin-resistant cancer cells. Synergy between this derivative and doxorubicin was observed. Most probably, TMPE inhibited transport activity of ABCB1 protein without affecting its expression level. Analysis of TMPE physicochemical parameters suggested it was not likely to be transported by ABCB1. Molecular modeling showed TMPE being more reactive molecule than the parental compound—β-cyclocitral. Analysis of electrostatic potential maps of both compounds prompted us to hypothesize that reduced reactivity as well as susceptibility to electrophilic attack were related to the lower general toxicity of β-cyclocitral. All of the above pointed to TMPE as an interesting candidate molecule for MDR reversal in cancer cells.