Long COVID-19 gastrointestinal related disorders and traditional Chinese medicine: A network target-based approach

The significant number of individuals impacted by the pandemic makes prolonged symptoms after COVID-19 a matter of considerable concern. These are numerous and affect multiple organ systems. According to the World Health Organization (WHO), prolonged gastrointestinal issues are a crucial part of post-COVID-19 syndrome. The resulting disruption of homeostasis underscores the need for a therapeutic approach based on compounds that can simultaneously affect more than one target/node. The present review aimed to check for nutraceuticals possessing multiple molecular mechanisms helpful in relieving Long COVID-19-specific gastrointestinal symptoms. Specific plants used in Keywords Chinese Medicine (TCM) expected to be included in the WHO Global Medical Compendium were selected based on the following criteria: (1) they are widely used in the Western world as natural remedies and complementary medicine adjuvants; (2) their import and trade are regulated by specific laws that ensure quality and safety (3) have the potential to be beneficial in alleviating intestinal issues associated with Long COVID-19. Searches were performed in PubMed, Elsevier, Google Scholar, Scopus, Science Direct, and ResearchGate up to 2023. Cinnamomum cassia, Glycyrrhiza uralensis, Magnolia officinalis, Poria cocos, Salvia miltiorrhiza, Scutellaria baicalensis, and Zingiber officinalis were identified as the most promising for their potential impact on inflammation and oxidative stress. Based on the molecular mechanisms of the phytocomplexes and isolated compounds of the considered plants, their clinical use may lead to benefits in gastrointestinal diseases associated with Long COVID-19, thanks to a multiorgan and multitarget approach.

Further Quinolizidine Derivatives as Antiarrhythmic Agents- 3

Fourteen quinolizidine derivatives, structurally related to the alkaloids lupinine and cytisine and previously studied for other pharmacological purposes, were presently tested for antiarrhythmic, and other cardiovascular effects on isolated guinea pig heart tissues in comparison to well-established reference drugs. According to their structures, the tested compounds are assembled into three subsets: (a) N-(quinolizidinyl-alkyl)-benzamides; (b) 2-(benzotriazol-2-yl)methyl-1-(quinolizidinyl)alkyl-benzimidazoles; (c) N-substituted cytisines. All compounds but two displayed antiarrhythmic activity that was potent for compounds 4, 1, 6, and 5 (in ascending order). The last compound (N-(3,4,5-trimethoxybenzoyl)aminohomolupinane) was outstanding, exhibiting a nanomolar potency (EC50 = 0.017 µM) for the increase in the threshold of ac-arrhythmia. The tested compounds shared strong negative inotropic activity; however, this does not compromise the value of their antiarrhythmic action. On the other hand, only moderate or modest negative chronotropic and vasorelaxant activities were commonly observed. Compound 5, which has high antiarrhythmic potency, a favorable cardiovascular profile, and is devoid of antihypertensive activity in spontaneously hypertensive rats, represents a lead worthy of further investigation.

hERG stereoselective modulation by mexiletine-derived ureas: Molecular docking study, synthesis, and biological evaluation

Long QT syndrome (LQTS) is a disorder of cardiac electrophysiology resulting in life-threatening arrhythmias; nowadays, only a few drugs are available for the management of LQTS. Focusing our attention on LQT2, one of the most common subtypes of LQTS caused by mutations in the human ether-à-go-go-related gene (hERG), in the present work, the stereoselectivity of the recently discovered mexiletine-derived urea 8 was investigated on the hERG potassium channel. According to preliminary in silico predictions, in vitro studies revealed a stereoselective behavior, with the meso form showing the greatest hERG opening activity. In addition, functional studies on guinea pig isolated left atria, aorta, and ileum demonstrated that 8 does not present any cardiac or intestinal liability in our ex vivo studies. Due to its overall profile, (R,S)-8 paves the way for the design and development of a new series of compounds potentially useful in the treatment of both congenital and drug-induced forms of LQTS.

Magnolia officinalis L. bark extract and respiratory diseases: From traditional Chinese medicine to western medicine via network target

The understanding of the use of Magnolia officinalis L. (Magnoliaceae) as a possible dietary supplement for supporting the treatment of airway pathologies might be of clinical interest. Two commercially available bark extracts (M. officinalis extract [MOE]) were characterized by quantitation in honokiol and magnolol content by means of high-performance liquid chromatography with UV detection. MOE effects, as well as those of the reference compounds per se, on some targets connected to airway pathologies (antibacterial- and lung and trachea relaxing- activities) were investigated. Results showed that MOE possessed interesting antibacterial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Streptococcus pneumoniae. This was accompanied by a spasmolytic and antispasmodic activity, possibly owing to its ability to concurrently modulate different targets such as H₁ -, β₂ - and muscarinic receptors and l-type calcium channels involved in bronchodilation. All these effects were directly related to the MOE content in honokiol and magnolol. In conclusion, the properties of MOE highlighted here strongly encourage its application as dietary supplement in the treatment of airway diseases.

A potential host and virus targeting tool against COVID-19: Chemical characterization, antiviral, cytoprotective, antioxidant, respiratory smooth muscle relaxant effects of Paulownia tomentosa Steud

COronaVIrus Disease 2019 (COVID-19) is a newly emerging infectious disease that spread across the world, caused by the novel coronavirus Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2). Despite the advancements in science that led to the creation of the vaccine, there is still an urgent need for new antiviral drugs effective against SARS-CoV-2. This study aimed to investigate the antiviral effect of Paulownia tomentosa Steud extract against SARS-CoV-2 and to evaluate its antioxidant properties, including respiratory smooth muscle relaxant effects. Our results showed that P. tomentosa extract can inhibit viral replication by directly interacting with both the 3-chymotrypsin-like protease and spike protein. In addition, the phyto complex does not reduce lung epithelial cell viability and exerts a protective action in those cells damaged by tert-butyl hydroperoxide , a toxic agent able to alter cells' functions via increased oxidative stress. These data suggest the potential role of P. tomentosa extract in COVID-19 treatment, since this extract is able to act both as an antiviral and a cytoprotective agent in vitro.

Tannins-Based Extracts: Effects on Gut Chicken Spontaneous Contractility

The impossibility of using drugs for the health of farm animals leads to the search for alternative strategies with two purposes: to maintain animal health and safeguard human health. In this perspective, tannins have shown great promises. These phytocomplexes obtained from natural matrices with multiple health properties may be used as a feed supplement in chicken farms. In this work, we studied two tannin-based extracts (from Castanea sativa Mill. wood and from Schinopsis balansae Engl. Quebracho Colorado hardwood) with different chemical compositions on the spontaneous contractility on the isolated intestinal tissues of healthy chicken. The results showed that the chemical composition of the two phytocomplexes influenced the spontaneous intestinal contractility in different ways by regulating the tone and consequent progression of the food bolus. The chemical analysis of the two extracts revealed that Castanea sativa Mill. wood mainly contains hydrolysable tannins, while Schinopsis balansae Engl. hardwood mainly contains condensed tannins. The two phytocomplexes showed different effects towards gastrointestinal smooth muscle contractility, with Castanea sativa Mill. wood providing a better activity profile than Schinopsis balansae Engl. hardwood.

Nutraceuticals, a Bridge Between Past and Future: Focus on Mushrooms Biological Activities and Myco-Chemistry

BACKGROUND

Mushrooms are consumed worldwide due to their high nutritional and nutraceutical values. In addition to the presence of various vitamins, low-fat, and proteins, they are also an important source of trace elements, dietary fibers, and bioactive compounds. Their potential therapeutic properties are due to their multiple biological effects, such as antimicrobial, antiviral, antioxidant, anticancer, immune-modulating, cardioprotective, and antidiabetic properties. The global market of mushroom farming is anticipated to witness remarkable progress for its potential application in health products, profitable production and a rising demand for the healthy foods across the globe. The Asia Pacific marketplace seems to represent the major market of mushrooms, due to the higher per capita consumption of culinary and medical purposes.

OBJECTIVE

Mushrooms have generally low calories, low levels of cholesterol, fats, gluten and sodium. Several biological effects of mushroom are due to the presence of phenolic components, polysaccharides, terpenoids, terphenyl-related compounds, and many other lower molecular weight molecules. This review aims at describing the chemical characterization of several mushrooms species and their biological effects.

CONCLUSION

The current review describes different secondary metabolites found in several mushrooms and mushrooms extracts, and the molecular mechanisms underlying the biological activities. Also the antimicrobial activities of mushrooms, mushrooms extracts and isolated compounds from mushrooms were described. The description of these activities, related to the presence of specific classes of secondary metabolites and isolated compounds, may lead to the identification of mycomplexes and mushrooms compounds that may be further studied for their potential application in nutraceutical products.

Microwave-Assisted Extraction of Bioactive Compounds from Lentil Wastes: Antioxidant Activity Evaluation and Metabolomic Characterization

The recovery of industrial by-products is part of the zero-waste circular economy. Lentil seed coats are generally considered to be a waste by-product. However, this low-value by-product is rich in bioactive compounds and may be considered an eco-friendly source of health-promoting phytochemicals. For the first time, a sustainable microwave-assisted extraction technique was applied, and a solvent screening was carried out to enhance the bioactive compound content and the antioxidant activity of green and red lentil hull extracts. With respect to green lentil hull extracts that were obtained with different solvents, the aqueous extract of the red lentil seed coats showed the highest total phenolic and total flavonoid content (TPC = 28.3 ± 0.1 mg GAE/g dry weight, TFC = 1.89 ± 0.01 mg CE/100 mg dry weight, respectively), as well as the highest antioxidant activity, both in terms of the free radical scavenging activity (ABTS, 39.06 ± 0.73 mg TE/g dry weight; DPPH, IC50 = 0.39 μg/mL) and the protection of the neuroblastoma cell line (SH-SY5Y, IC50 = 10.1 ± 0.6 μg/mL), the latter of which has never been investigated so far. Furthermore, a metabolite discovery analysis was for the first time performed on the aqueous extracts of both cultivars using an HPLC separation which was coupled with an Orbitrap-based high-Resolution Mass Spectrometry technique.

Polyphenols from Olive-Mill Wastewater and Biological Activity: Focus on Irritable Bowel Syndrome

Waste represents a cost for companies, in particular for agro-food companies, which can become a resource as a secondary material. In this work, we examine three products of olive-oil waste water, named MOMAST® (Plus30, PW25, and HY100). Based on the chemical composition, obtained with different methods, we hypothesized a possible application as food supplements in irritable bowel syndrome (IBS). We therefore studied MOMASTs on some targets linked to this pathology: antioxidant action and spontaneous and induced intestinal contractility of the ileum and colon. Plus30, which showed a more promising biological of activity also for its oleuropein content, was characterized by an interesting action against some microorganisms. The results highlighted the ability of Plus30 to modulate spontaneous and induced contractility, to exert a good antioxidant action, and to significantly act on various microorganisms. These effects are synergistic in the presence of antibiotics. In conclusion, we can confirm that Plus30 could be a great candidate as a food supplement in patients with IBS.

Olea europea L. Leaves and Hibiscus sabdariffa L. Petals Extracts: Herbal Mix from Cardiovascular Network Target to Gut Motility Dysfunction Application

It is well known that diet and nutrition play a critical role in the etiopathogenesis of many disorders. On the other hand, nutrients or bioactive compounds can specifically target and control various aspects of the mechanism underlying the pathology itself, and, in this context, diseases related to intestinal motility disorders stand out. The Herbal Mix (HM) consisting of Olea europea L. leaf (OEE) and Hibiscus sabdariffa L. (HSE) extracts (13:2) has been proven to be a promising nutraceutical option for many diseases, but its potential in inflammatory-driven gastrointestinal disorders is still unexplored. In this study, HM effects on guinea-pig ileum and colon contractility (induced or spontaneous) and on human iNOS activity, as well as on human colorectal adenocarcinoma Caco-2 cells, were studied. Results showed that the HM can control the ileum and colon contractility without blocking the progression of the food bolus, can selectively inhibit iNOS and possesses a strong pro-apoptotic activity towards Caco-2 cells. In conclusion, the present results suggest that, in some diseases, such as those related to motility disorders, an appropriate nutritional approach can be accompanied by a correct use of nutraceuticals that could help not only in ameliorating the symptoms but also in preventing more severe, cancer-related conditions.

Hibiscus Flower and Olive Leaf Extracts Activate Apoptosis in SH-SY5Y Cells

Compounds of natural origin may constitute an interesting tool for the treatment of neuroblastoma, the most prevalent extracranial solid tumor in children. PRES is a commercially available food supplement, composed of a 13:2 (w/w) extracts mix of Olea europaea L. leaves (OE) and Hibiscus sabdariffa L. flowers (HS). Its potential towards neuroblastoma is still unexplored and was thus investigated in human neuroblastoma SH-SY5Y cells. PRES decreased the viability of cells in a concentration-dependent fashion (24 h IC₅₀ 247.2 ± 31.8 µg/mL). Cytotoxicity was accompanied by an increase in early and late apoptotic cells (AV-PI assay) and sub G0/G1 cells (cell cycle analysis), ROS formation, reduction in mitochondrial membrane potential, and caspases activities. The ROS scavenger N-acetyl-L-cysteine reverted the cytotoxic effects of PRES, suggesting a key role played by ROS in PRES-mediated SH-SY5Y cell death. Finally, the effects of OE and HS extracts were singularly tested and compared to those of the corresponding mixture. OE- or HS-mediated cytotoxicity was always significantly lower than that caused by PRES, suggesting a synergic effect. In conclusion, the present findings highlight the potential of PRES for the treatment of neuroblastoma and offers the basis for a further characterization of the mechanisms underlying its effects.

SARS-CoV-2: lessons from both the history of medicine and from the biological behavior of other well-known viruses

SARS-CoV-2 is the etiological agent of the current pandemic worldwide and its associated disease COVID-19. In this review, we have analyzed SARS-CoV-2 characteristics and those ones of other well-known RNA viruses viz. HIV, HCV and Influenza viruses, collecting their historical data, clinical manifestations and pathogenetic mechanisms. The aim of the work is obtaining useful insights and lessons for a better understanding of SARS-CoV-2. These pathogens present a distinct mode of transmission, as SARS-CoV-2 and Influenza viruses are airborne, whereas HIV and HCV are bloodborne. However, these viruses exhibit some potential similar clinical manifestations and pathogenetic mechanisms and their understanding may contribute to establishing preventive measures and new therapies against SARS-CoV-2.

Paradoxical relationship between proton pump inhibitors and COVID-19: A systematic review and meta-analysis

BACKGROUND

The proton pump inhibitors (PPIs), used to reduce gastric acid secretion, represent one of the most widely used pharmaceutical classes in the world. Their consumption as a risk factor for the evolution of severe forms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been investigated as well as the mortality of these patients. These risks also appear to be linked to the duration and the dosage. On the other hand, several studies have emerged with regard to the protective or therapeutic effects of these drugs. More and more evidence underlines the immunomodulatory and anti-fibrotic role of PPIs. In addition, their ability to alkalize the contents of endosomes and lysosomes serves as an obstacle to the entry of the virus into the host cells.

AIM

To identify studies on the relationship between the intake of PPIs and coronavirus disease 2019 (COVID-19) in patients affected by SARS-CoV-2 infection, with the main objective of evaluating the outcomes related to severity and mortality.

METHODS

A literature review was performed in November 2020. The MEDLINE/PubMed, Cochrane Library, EMBASE and Google Scholar databases were searched for all relevant articles published in English on this topic. The search terms were identified by means of controlled vocabularies, such as the National Library of Medicine's MESH (Medical Subject Headings) and keywords. The MESH terms and keywords used were as follows: "COVID-19", "proton pump inhibitors", "PPIs", "SARS-CoV-2", "outcomes", "severity" and "mortality". The inclusion criteria regarding the studies considered in our analysis were: meta-analysis, case-control, hospital-based case-control, population-based case-control, retrospective studies, online survey, as well as cohort-studies, while articles not published as full reports, such as conference abstracts, case reports and editorials were excluded. We tried to summarize and pool all the data if available.

RESULTS

A total of 9 studies were found that described the use of PPIs, of which only 5 clearly reported the severity and mortality data in SARS-CoV-2 patients. Our pooled incidence analysis of severe events did not differ between patients with and without PPIs (odds ratio 1.65, 95% confidence interval: 0.62-4.35) (P = 0.314), or for mortality (odds ratio 1.77, 95% confidence interval: 0.62-5.03) (P = 0.286).

CONCLUSION

Detailed and larger case studies are needed to accurately understand the role of PPIs in this viral infection.

Olive Tree in Circular Economy as a Source of Secondary Metabolites Active for Human and Animal Health Beyond Oxidative Stress and Inflammation

Extra-virgin olive oil (EVOO) contains many bioactive compounds with multiple biological activities that make it one of the most important functional foods. Both the constituents of the lipid fraction and that of the unsaponifiable fraction show a clear action in reducing oxidative stress by acting on various body components, at concentrations established by the European Food Safety Authority's claims. In addition to the main product obtained by the mechanical pressing of the fruit, i.e., the EVOO, the residual by-products of the process also contain significant amounts of antioxidant molecules, thus potentially making the Olea europea L. an excellent example of the circular economy. In fact, the olive mill wastewaters, the leaves, the pomace, and the pits discharged from the EVOO production process are partially recycled in the nutraceutical and cosmeceutical fields also because of their antioxidant effect. This work presents an overview of the biological activities of these by-products, as shown by in vitro and in vivo assays, and also from clinical trials, as well as their main formulations currently available on the market.

Modifications at C(5) of 2-(2-Pyrrolidinyl)-Substituted 1,4-Benzodioxane Elicit Potent α4β2 Nicotinic Acetylcholine Receptor Partial Agonism with High Selectivity over the α3β4 Subtype

A series of diastereomeric 2-(2-pyrrolidinyl)-1,4-benzodioxanes bearing a small, hydrogen-bonding substituent at the 7-, 6-, or 5-position of benzodioxane have been studied for α4β2 and α3β4 nicotinic acetylcholine receptor affinity and activity. Analogous to C(5)H replacement with N and to a much greater extent than decoration at C(7), substitution at benzodioxane C(5) confers very high α4β2/α3β4 selectivity to the α4β2 partial agonism. Docking into the two receptor structures recently determined by cryo-electron microscopy and site-directed mutagenesis at the minus β2 side converge in indicating that the limited accommodation capacity of the β2 pocket, compared to that of the β4 pocket, makes substitution at C(5) rather than at more projecting C(7) position determinant for this pursued subtype selectivity.

Castanea sativa Mill. bark extract cardiovascular effects in a rat model of high-fat diet

Ellagitannins may have a beneficial impact in cardiovascular diseases. The aim of the study was to evaluate the effect of high-fat diet (HFD) and the efficacy of Castanea sativa Mill. bark extract (ENC) on cardiac and vascular parameters. Rats were fed with regular diet, (RD, n = 15), HFD (n = 15), RD + ENC (20 mg/kg/day by gavage, n = 15), and HFD + ENC (same dose, n = 15) and the effects on body weight, biochemical serum parameters, and inflammatory cytokines determined. Cardiac functional parameters and aorta contractility were also assessed on isolated atria and aorta. Results showed that ENC reduced weight gain and serum lipids induced by HFD. In in vitro assays, HFD decreased the contraction force of left atrium, increased right atrium chronotropy, and decreased aorta K⁺ -induced contraction; ENC induced transient positive inotropic and negative chronotropic effects on isolated atria from RD and HFD rats and a spasmolytic effect on aorta. In ex vivo experiments, ENC reverted inotropic and chronotropic changes induced by HFD and enhanced Nifedipine effect more on aorta than on heart. In conclusion, ENC restores metabolic dysfunction and cardiac cholinergic muscarinic receptor function, and exerts spasmolytic effect on aorta in HFD rats, highlighting its potential as nutraceutical tool in obesity.

Activity of Antioxidants from Crocus sativus L. Petals: Potential Preventive Effects towards Cardiovascular System

The petals of the saffron crocus (Crocus sativus L.) are considered a waste material in saffron production, but may be a sustainable source of natural biologically active substances of nutraceutical interest. The aim of this work was to study the cardiovascular effects of kaempferol and crocin extracted from saffron petals. The antiarrhythmic, inotropic, and chronotropic effects of saffron petal extract (SPE), kaempferol, and crocin were evaluated through in vitro biological assays. The antioxidant activity of kaempferol and crocin was investigated through the 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) assay using rat cardiomyoblast cell line H9c2. The MTT assay was applied to assess the effects of kaempferol and crocin on cell viability. SPE showed weak negative inotropic and chronotropic intrinsic activities but a significant intrinsic activity on smooth muscle with a potency on the ileum greater than on the aorta: EC₅₀ = 0.66 mg/mL versus EC₅₀ = 1.45 mg/mL. Kaempferol and crocin showed a selective negative inotropic activity. In addition, kaempferol decreased the contraction induced by KCl (80 mM) in guinea pig aortic and ileal strips, while crocin had no effect. Furthermore, following oxidative stress, both crocin and kaempferol decreased intracellular ROS formation and increased cell viability in a concentration-dependent manner. The results indicate that SPE, a by-product of saffron cultivation, may represent a good source of phytochemicals with a potential application in the prevention of cardiovascular diseases.

Synthesis and Evaluation of Voltage-Gated Sodium Channel Blocking Pyrroline Derivatives Endowed with Both Antiarrhythmic and Antioxidant Activities

Under the hypothesis that cardioprotective agents might benefit from synergism between antiarrhythmic activity and antioxidant properties, a small series of mexiletine analogues were coupled with the 2,2,5,5-tetramethylpyrroline moiety, known for its antioxidant effect, in order to obtain dual-acting drugs potentially useful in the protection of the heart against post-ischemic reperfusion injury. The pyrroline derivatives reported herein were found to be more potent as antiarrhythmic agents than mexiletine and displayed antioxidant activity. The most interesting tetramethylpyrroline congener, a tert-butyl-substituted analogue, was at least 100 times more active as an antiarrhythmic than mexiletine.

Thymus vulgaris L. Essential Oil Solid Formulation: Chemical Profile and Spasmolytic and Antimicrobial Effects

A new Thymus vulgaris L. solid essential oil (SEO) formulation composed of liquid EO linked to solid excipients has been chemically analysed and evaluated for its intestinal spasmolytic and antispastic effects in ex vivo ileum and colon of guinea pig and compared with liquid EO and excipients. Liquid EO and solid linked EO were analysed by original capillary electrochromatography coupled to diode array detection (CEC-DAD) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) methodologies. The main bioactive constituents are thymol and carvacrol, with minor constituents for a total of 12 selected analysed compounds. Liquid EO was the most effective in decreasing basal contractility in ileum and colon; excipients addiction permitted normal contractility pattern in solid linked EO SEO. In ileum and colon, the Thymus vulgaris L. solid formulation exerted the relaxant activity on K⁺-depolarized intestinal smooth muscle as well as liquid EO. The solid essential oil exhibits antimicrobial activity against different strains (Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa, Escherichia coli, Salmonella Thyphimurium, Candida albicans) similarly to liquid oil, with activity against pathogen, but not commensal strains (Bifidobacterium Breve, Lactobacillus Fermentum) in intestinal homeostasis. Therefore, Thymus vulgaris L. solid essential oil formulation can be proposed as a possible spasmolytic and antispastic tool in medicine.

Antihypertensive phytocomplexes of proven efficacy and well-established use: Mode of action and individual characterization of the active constituents

Hypertension has become the leading risk factor for worldwide cardiovascular diseases. Conventional pharmacological treatment, after both dietary and lifestyle changes, is generally proposed. In this review, we present the antihypertensive properties of phytocomplexes from thirteen plants, long ago widely employed in ethnomedicines and, in recent years, increasingly evaluated for their activity in vitro and in vivo, also in humans, in comparison with synthetic drugs acting on the same systems. Here, we focus on the demonstrated or proposed mechanisms of action of such phytocomplexes and of their constituents proven to exert cardiovascular effects. Almost seventy phytochemicals are described and scientifically sound pertinent literature, published up to now, is summarized. The review emphasizes the therapeutic potential of these natural substances in the treatment of the 'high normal blood pressure' or 'stage 1 hypertension', so-named according to the most recent European and U.S. guidelines, and as a supplementation in more advanced stages of hypertension, however needing further validation by clinical trial intensification.

Impact of phytosterols on liver and distal colon metabolome in experimental murine colitis model: an explorative study

Phytosterols are known to reduce plasma cholesterol levels and thereby reduce cardiovascular risk. Studies conducted on human and animal models have demonstrated that these compounds have also anti-inflammatory effects. Recently, an experimental colitis model (dextran sulphate sodium-induced) has shown that pre-treatment with phytosterols decreases infiltration of inflammatory cells and accelerates mucosal healing. This study aims to understand the mechanism underlying the colitis by analysing the end-products of the metabolism in distal colon and liver excised from the same mice used in the previous work. In particular, an unsupervised gas chromatography-mass spectrometry (GC-MS) and NMR based metabolomics approach was employed to identify the metabolic pathways perturbed by the dextran sodium sulphate (DSS) insult (i.e. Krebs cycle, carbohydrate, amino acids, and nucleotide metabolism). Interestingly, phytosterols were able to restore the homeostatic equilibrium of the hepatic and colonic metabolome.

Potent Antiglioblastoma Agents by Hybridizing the Onium-Alkyloxy-Stilbene Based Structures of an α7-nAChR, α9-nAChR Antagonist and of a Pro-Oxidant Mitocan

Adenocarcinoma and glioblastoma cell lines express α7- and α9α10-containing nicotinic acetylcholine receptors (nAChRs), whose activation promotes tumor cell growth. On these cells, the triethylammoniumethyl ether of 4-stilbenol MG624, a known selective antagonist of α7 and α9α10 nAChRs, has antiproliferative activity. The structural analogy of MG624 with the mitocan RDM-4'BTPI, triphenylphosphoniumbutyl ether of pterostilbene, suggested us that molecular hybridization among their three substructures (stilbenoxy residue, alkylene linker, and terminal onium) and elongation of the alkylene linker might result in novel antitumor agents with higher potency and selectivity. We found that lengthening the ethylene bridge in the triethylammonium derivatives results in more potent and selective toxicity toward adenocarcinoma and glioblastoma cells, which was paralleled by increased α7 and α9α10 nAChR antagonism and improved ability of reducing mitochondrial ATP production. Elongation of the alkylene linker was advantageous also for the triphenylphosphonium derivatives resulting in a generalized enhancement of antitumor activity, associated with increased mitotoxicity.

Ayurvedic preparation of Zingiber officinale Roscoe: effects on cardiac and on smooth muscle parameters

The rhizome of the Zingiber officinale Roscoe, a biennial herb growing in South Asia, is commonly known as ginger. Ginger is used in clinical disorders, such as constipation, dyspepsia, diarrhoea, nausea and vomiting and its use is also recommended by the traditional medicine for cardiopathy, high blood pressure, palpitations and as a vasodilator to improve the circulation. The decoction of ginger rhizome is widely used in Ayurvedic medicine. In this papery by high-performance liquid chromatography, we have seen that its main phytomarkers were 6-gingerol, 8-gingerol and 6-shogaol and we report the effects of the decoction of ginger rhizome on cardiovascular parameters and on vascular and intestinal smooth muscle. In our experimental models, the decoction of ginger shows weak negative inotropic and chronotropic intrinsic activities but a significant intrinsic activity on smooth muscle with a potency on ileum is greater than on aorta: EC50 = 0.66 mg/mL versus EC50 = 1.45 mg/mL.

Apoptotic-induced Effects of Castanea sativa Bark Extract in Human SH-SY5Y Neuroblastoma Cells

Castanea sativa Mill. wood extract (ENC) has health-promoting qualities such as antibacterial, antiviral, antispasmodic, cardio- and neuroprotective-activities. Its potential towards cancer cells of the central nervous system, however, is still unexplored. This study investigates the apoptotic-enhancing effect of ENC in human neuroblastoma SH-SY5Y cell line. This extract irreversibly decreased cell viability with IC50 of 142.8±20.2, 109.3±16.6 and 82.5±8.6 μg/mL for 24h, 48 and 72h of treatment, respectively. This was accompanied by cell shrinkage and tendency to round-up. A concentration-dependent increase in sub G0/G1 cells as well as a rise in cells with nuclear fragmentation and chromatin condensation, both typical of apoptosis, was also observed. In conclusion, the present findings provide initial data on the potential of ENC for neuroblastoma treatment and offer the rationale for further studies aimed at elucidating the full mechanism(s) underlying its effects.

In vitro activity of Spirulina platensis water extract against different Candida species isolated from vulvo-vaginal candidiasis cases

The high incidence of vulvo-vaginal candidiasis, combined with the growing problems about azole resistance and toxicity of antifungal drugs, highlights the need for the development of new effective strategies for the treatment of this condition. In this context, natural compounds represent promising alternatives. The cyanobacterium Spirulina platensis, a blue-green alga, exhibits antimicrobial activities against several microorganisms. Nevertheless, only few data about the antifungal properties of Spirulina platensis are available and its potential toxic effects have not been largely investigated. The aim of this study was to evaluate the in vitro activity of a fully-characterized water extract of Spirulina platensis against 22 strains of Candida spp. Prior to considering its potential topical use, we both investigated whether the extract exerted target activities on guinea pig uterine smooth muscle, and the impact of Spirulina platensis on the dominant microorganisms of the vaginal microbiota (i.e., lactobacilli), in order to exclude possible adverse events. By means of a broth microdilution assay, we found that the microalga extract possesses good antifungal properties (MIC: 0.125-0.5 mg/ml), against all the Candida species with a fungicidal activity. At the concentrations active against candida, Spirulina platensis did not modify the spontaneous basic waves pattern of uterine myometrium as underlined by the absence of aberrant contractions, and did not affect the main health-promoting bacteria of the vaginal ecosystem. Finally, we evaluated the selectivity index of our extract by testing its cytotoxicity on three different cell lines and it showed values ranging between 2 and 16. Further in vivo studies are needed, in particular to evaluate the use of control-release formulations in order to maintain Spirulina platensis concentrations at anti-Candida active doses but below the toxic levels found in the present work.

Hibiscus Sabdariffa L. Flowers and Olea Europea L. Leaves Extract-Based Formulation for Hypertension Care: In Vitro Efficacy and Toxicological Profile

Olea europaea L. leaves extract (Oe) and Hybiscus sabdariffa L. flowers extract (Hs) have calcium antagonistic properties. Aim of this work was to study the cardiovascular effects of Pres Phytum(®), a nutraceutical formulation containing a mixture of the two extracts and the excipients, and investigate its possible off-target effects, using in vitro biological assays on guinea pig isolated organs. Cardiovascular effects were assessed using guinea pig atria and aorta. The effects of Pres Phytum on spontaneous gastrointestinal, urinary, and respiratory tracts smooth muscle contractility were evaluated. Pres Phytum exerted a vasorelaxant effect (IC50 = 2.38 mg/mL) and a negative chronotropic effect (IC50 = 1.04 mg/mL) at concentrations lower than those producing smooth muscle spontaneous contractility alterations in the other organs. Compared to Pres Phytum, the mixture did not exert negative inotropic activity, while it maintained a negative chronotropic efficacy (IC50 = 1.04 mg/mL). These experimental data suggest a possible nutraceutical use of this food supplement for the management of preclinical hypertension.

In vitro activity of a partially purified and characterized bark extract of Castanea sativa Mill. (ENC®) against Chlamydia spp

Castanea sativa Mill (ENC®), containing tannins against 33 Chlamydia strains, was compared to SMAP-29 with inhibitory effect against C. trachomatis and C. pneumoniae. The ENC® activity against Chlamydia spp. was evaluated determining the lowest concentration to achieve more than half reduction of intact chlamydial inclusions versus controls. ENC® reduced all Chlamydia strains tested at 1 µg/mL, while SMAP-29 induced reductions of C. trachomatis and C. pneumoniae infectivity at 10 µg/mL. A great reduction of C. trachomatis, C. pneumoniae, and C. abortus infectivity was achieved with a 10 µg/mL ENC® concentration, whereas their infectivity was almost inhibited at 100 µg/mL ENC® concentration.

Castanea sativa Mill. Bark Extract Protects U-373 MG Cells and Rat Brain Slices Against Ischemia and Reperfusion Injury

Ischemic brain injury is one of the most important causes of death worldwide. The use of one-drug-multi-target agents based on natural compounds is a promising therapeutic option for cerebral ischemia due to their pleiotropic properties. This study assessed the neuroprotective properties of Castanea sativa Mill. bark extract (ENC) in human astrocytoma U-373 MG cells subjected to oxygen-glucose deprivation and reperfusion and rat cortical slices subjected to ischemia-like conditions or treated with glutamate or hydrogen peroxide. Neuroprotective effects were determined by assessing cells or slices viability (MTT assay), ROS formation (DCFH-DA assay), apoptosis (sub G0/G1 peak), nuclear fragmentation and chromatin condensation (DAPI staining) as well as changes in lysosomes and mitochondria morphology (Acridine Orange and Rhodamine123 staining, respectively). ENC treatment before injury on U-373 MG cells (5-50 μg/ml) and cortical slices (50-100 μg/ml) provided neuroprotection, while lower or higher concentrations (100 μg/ml U-373 MG cells, 200 μg/ml brain slices) were ineffective. ENC addition during reperfusion or after the injury was not found to be effective. The results suggest that ENC might hold potential as preventive neuroprotective agent, and indicate the importance of further studies exploring its mechanism of action. J. Cell. Biochem. 118: 839-850, 2017. © 2016 Wiley Periodicals, Inc.

Understanding Oxadiazolothiazinone Biological Properties: Negative Inotropic Activity versus Cytochrome P450-Mediated Metabolism

We present a series of oxadiazolothiazinones, selective inotropic agents on isolated cardiac tissues, devoid of chronotropy and vasorelaxant activity. Functional and binding data for the precursor of the series (compound 1) let us hypothesize LTCC blocking activity and the existence of a recognition site specific for this scaffold. We synthesized and tested 22 new derivatives: introducing a para-methoxyphenyl at C-8 led to compound 12 (EC50 = 0.022 μM), twice as potent as its para-bromo analogue (1). For 10 analogues, we extended the characterization of the biological properties by including the assessment of metabolic stability in human liver microsomes and cytochrome P450 inhibition potential. We observed that the methoxy group led to active compounds with low metabolic stability and high CYP inhibition, whereas the protective effect of bromine resulted in enhanced metabolic stability and reduced CYP inhibition. Thus, we identified two para-bromo benzothiazino-analogues as candidates for further studies.

Neuroprotective Effects of Castanea sativa Mill. Bark Extract in Human Neuroblastoma Cells Subjected to Oxidative Stress

One of the major features of neurodegenerative disease is the selective vulnerability of different neuronal populations that are affected in a progressive and often stereotyped manner. Despite the susceptible neuronal population varies between diseases, oxidative stress is implicated as the major pathogenic process in all of them. Natural Extract of Castanea sativa Mill. bark (ENC), recently characterized in its phenolic composition, acts as antioxidant and cardioprotective agent. Its neuroprotettive properties, however, have never been investigated. The aim of this study was to assess neuroprotection of ENC in in vitro models of oxidative-stress-mediate injury. Human neuroblastoma SH-SY5Y cells treated with glutamate (50 mM for 24 h) or hydrogen peroxide (25 μM for 1 h followed by 24 with medium) were used. The results showed that the addition of ENC (1-50 μg/ml) to cell medium before the neuronal damage provided neuroprotection in both experimental models used, while its addition after the injury was ineffective. In conclusion, the present results suggest that ENC could be a valuable support as dietary supplement, combining beneficial preventive neuroprotettive effects with a high antioxidant activity.

Chemistry and Pharmacology of a Series of Unichiral Analogues of 2-(2-Pyrrolidinyl)-1,4-benzodioxane, Prolinol Phenyl Ether, and Prolinol 3-Pyridyl Ether Designed as α4β2-Nicotinic Acetylcholine Receptor Agonists

Some unichiral analogues of 2R,2'S-2-(1'-methyl-2'-pyrrolidinyl)-7-hydroxy-1,4-benzodioxane, a potent and selective α4β2-nAChR partial agonist, were designed by opening dioxane and replacing hydroxyl carbon with nitrogen. The resulting 3-pyridyl and m-hydroxyphenyl ethers have high α4β2 affinity and good subtype selectivity, which get lost if OH is removed from phenyl or the position of pyridine nitrogen is changed. High α4β2 affinity and selectivity are also attained by meta hydroxylating the 3-pyridyl and the phenyl ethers of (S)-N-methylprolinol and the phenyl ether of (S)-2-azetidinemethanol, known α4β2 agonists, although the interaction mode of the aryloxymethylene substructure cannot be assimilated to that of benzodioxane. Indeed, the α4β2 and α3β4 functional tests well differentiate behaviors that the binding tests homologize: both the 3-hydroxyphenyl and the 5-hydroxy-3-pyridyl ether of N-methylprolinol are α4β2 full agonists, but only the latter is highly α4β2/α3β4 selective, while potent and selective partial α4β2 agonism characterizes the hydroxybenzodioxane derivative and its two opened semirigid analogues.

Synthesis and L-type calcium channel blocking activity of new chiral oxadiazolothiazinones

Oxadiazolo[3,4-c][1,4]thiazin-3-ones are cardiovascular agents that block L-type calcium channels. Previous data of cardiac and vasorelaxant activity on guinea-pig for several derivatives indicated the two positions ortho to the thiazine's sulphur as crucial for modulating the activity; but these positions are likely susceptible to metabolic biotransformations, as indicated by in silico predictions. We designed new derivatives, and obtained three negative inotropic agents with EC50 in the low nanomolar range, more potent than all the precursors published so far. In particular, benzocondensation at the thiazine ring led to 3a (EC50 = 0.013 μM) and 3b (EC50 = 0.006 μM). Besides negative inotropy, we also observed relaxant activity on nonvascular muscle in the micromolar range. We resolved the new derivatives by chiral chromatography, and determined their absolute configuration by comparing experimental and calculated chiroptical properties (VCD, ECD and ORD): they hold the same absolute configuration-optical rotation relationship, (S)-(+)/(R)-(-). Both cardiac and nonvascular activity are majorly or mostly retained in the R-form for all the compounds, but for the nonvascular activity we observed a strong stereoselectivity for 3a, with the R-form in the nanomolar range (IC50 = 0.020 μM) and 259-fold more potent than the S-one.

Playing with opening and closing of heterocycles: using the cusmano-ruccia reaction to develop a novel class of oxadiazolothiazinones, active as calcium channel modulators and P-glycoprotein inhibitors

As a result of the ring-into-ring conversion of nitrosoimidazole derivatives, we obtained a molecular scaffold that, when properly decorated, is able to decrease inotropy by blocking L-type calcium channels. Previously, we used this scaffold to develop a quantitative structure-activity relationship (QSAR) model, and we used the most potent oxadiazolothiazinone as a template for ligand-based virtual screening. Here, we enlarge the diversity of chemical decorations, present the synthesis and in vitro data for 11 new derivatives, and develop a new 3D-QSAR model with recent in silico techniques. We observed a key role played by the oxadiazolone moiety: given the presence of positively charged calcium ions in the transmembrane channel protein, we hypothesize the formation of a ternary complex between the oxadiazolothiazinone, the Ca2+ ion and the protein. We have supported this hypothesis by means of pharmacophore generation and through the docking of the pharmacophore into a homology model of the protein. We also studied with docking experiments the interaction with a homology model of P-glycoprotein, which is inhibited by this series of molecules, and provided further evidence toward the relevance of this scaffold in biological interactions.

Antiinflammatory effect of phytosterols in experimental murine colitis model: prevention, induction, remission study

Phytosterols, besides hypocholesterolemic effect, present anti-inflammatory properties. Little information is available about their efficacy in Inflammatory Bowel Disease (IBD). Therefore, we have evaluated the effect of a mixture of phytosterols on prevention/induction/remission in a murine experimental model of colitis. Phytosterols were administered x os before, during and after colitis induction with Dextran Sodium Sulfate (DSS) in mice. Disease Activity Index (DAI), colon length, histopathology score, 18F-FDG microPET, oxidative stress in the intestinal tissue (ileum and colon) and gallbladder ileum and colon spontaneous and carbachol (CCh) induced motility, plasma lipids and plasma, liver and biliary bile acids (BA) were evaluated. A similar longitudinal study was performed in a DSS colitis control group. Mice treated with DSS developed severe colitis as shown by DAI, colon length, histopathology score, 18F-FDG microPET, oxidative stress. Both spontaneous and induced ileal and colonic motility were severely disturbed. The same was observed with gallbladder. DSS colitis resulted in an increase in plasma cholesterol, and a modification of the BA pattern. Phytosterols feeding did not prevent colitis onset but significantly reduced the severity of the disease and improved clinical and histological remission. It had strong antioxidant effects, almost restored colon, ileal and gallbladder motility. Plasmatic levels of cholesterol were also reduced. DSS induced a modification in the BA pattern consistent with an increase in the intestinal BA deconjugating bacteria, prevented by phytosterols. Phytosterols seem a potential nutraceutical tool for gastrointestinal inflammatory diseases, combining metabolic systematic and local anti-inflammatory effects.

Castanea sativa Mill. extract contracts gallbladder and relaxes sphincter of Oddi in guinea pig: a natural approach to biliary tract motility disorders

Impaired gallbladder motility is a contributing factor to gallstone formation. Since many drugs delaying intestinal motility inhibit gallbladder emptying, the aim of the present study was to evaluate the effect on gallbladder and sphincter of Oddi motility of a Natural Chestnut Wood Extract (NEC) that reduces intestinal motility. In order to evaluate the effect of the extract in normal- and high-risk gallstone conditions, the investigation was performed using tissues from animals fed normal and lithogenic diet. Fifty guinea pigs were administered either control or lithogenic diet. The spontaneous motility of the gallbladder and sphincter of Oddi were recorded on isolated gallbladder tissues; thereafter, the effect of NEC on motility was tested and compared with carbachol (CCh), potassium chloride (KCl), noradrenaline (NA), and A71623. Compared to controls, the lithogenic diet induced an irregular and disordered motor pattern in both the gallbladder and sphincter of Oddi. NEC increased gallbladder and decreased sphincter of Oddi spontaneous motility independently of cholinergic, adrenergic, and CCK-1 receptor-mediated pathways both in controls and in lithogenic diet-fed animals, although the effect was lower in the latter group. The effect was reversible and mediated by calcium channels. The natural extract of chestnut increasing gallbladder contraction and inducing the relaxation of the sphincter of Oddi can be of benefit in pathological conditions associated with increased transit time at risk of gallstones.

Curcuma longa L. as a therapeutic agent in intestinal motility disorders. 2: Safety profile in mouse

BACKGROUND

Curcuma extract exerts a myorelaxant effect on the mouse intestine. In view of a possible use of curcuma extract in motor functional disorders of the gastrointestinal tract, a safety profile study has been carried out in the mouse.

METHODS

Thirty mice were used to study the in vitro effect of curcuma on gallbladder, bladder, aorta and trachea smooth muscular layers and hearth inotropic and chronotropic activity. The myorelaxant effect on the intestine was also thoroughly investigated. Moreover, curcuma extract (200 mg/Kg/day) was orally administered to twenty mice over 28 days and serum liver and lipids parameters were evaluated. Serum, bile and liver bile acids qualitative and quantitative composition was were also studied.

RESULTS

In the intestine, curcuma extract appeared as a not competitive inhibitor through cholinergic, histaminergic and serotoninergic receptors and showed spasmolytic effect on K(+) induced contraction at the level of L type calcium channels. No side effect was observed on bladder, aorta, trachea and heart when we used a dose that is effective on the intestine. An increase in gallbladder tone and contraction was observed. Serum liver and lipids parameters were normal, while a slight increase in serum and liver bile acids concentration and a decrease in bile were observed.

CONCLUSIONS

Although these data are consistent with the safety of curcuma extract as far as its effect on the smooth muscular layers of different organs and on the heart, the mild cholestatic effect observed in absence of alteration of liver function tests must be further evaluated and the effective dose with minimal side effects considered.

6-methoxy-7-benzofuranoxy and 6-methoxy-7-indolyloxy analogues of 2-[2-(2,6-Dimethoxyphenoxy)ethyl]aminomethyl-1,4-benzodioxane (WB4101):1 discovery of a potent and selective α1D-adrenoceptor antagonist

Previous results have shown that replacement of one of the two o-methoxy groups at the phenoxy residue of the potent, but not subtype-selective, α1-AR antagonist (S)-WB4101 [(S)-1] by phenyl, or by ortho,meta-fused cyclohexane, or especially by ortho,meta-fused benzene preferentially elicits α1D-AR antagonist affinity. Such observations inspired the design of four new analogues of 1 bearing, in lieu of the 2,6-dimethoxyphenoxy residue, a 6-methoxy-substituted 7-benzofuranoxy or 7-indolyloxy group or, alternatively, their corresponding 2,3-dihydro form. Of these new compounds, which maintain, rigidified, the characteristic ortho heterodisubstituted phenoxy substructure of 1, the S enantiomer of the dihydrobenzofuranoxy derivative exhibited the highest α1D-AR antagonist affinity (pA2 9.58) with significant α1D/α1A and α1D/α1B selectivity. In addition, compared both to α1D-AR antagonists structurally related to 1 and to the well-known α1D-AR antagonist BMY7378, this derivative had modest 5-HT1A affinity and neutral α1-AR antagonist behavior.

Ligand based approach to L-type calcium channel by imidazo[2,1-b]thiazole-1,4-dihydropyridines: from heart activity to brain affinity

The synthesis, characterization, and functional in vitro assay in cardiac and smooth muscle (vascular and nonvascular) of a series of 4-imidazo[2,1-b]thiazole-1,4-dihydropyridines are reported. To define the calcium blocker nature of the imidazo[2,1-b]thiazole-1,4-DHPs and their selectivity on Cav1.2 and Cav1.3 isoforms, we performed binding studies on guinea pig atrial and ventricular membranes on intact cells expressing the cloned Cav1.2a subunit and on rat brain cortex. To get major insights into the reasons for the affinity for Cav1.2 and/or Cav1.3, molecular modeling studies were also undertaken. Some physicochemical and pharmacokinetic properties of selected compounds were calculated and compared. All the biological data collected and reported herein allowed us to rationalize the structure-activity relationship of the 4-imidazo[2,1-b]thiazole-1,4-DHPs and to identify which of these enhanced the activity at the central level.

Affinity and activity profiling of unichiral 8-substituted 1,4-benzodioxane analogues of WB4101 reveals a potent and selective α1B-adrenoceptor antagonist

Unichiral 8-substituted analogues of 2-[(2-(2,6-dimethoxyphenoxy)ethyl)aminomethyl]-1,4-benzodioxane (WB4101) were synthesized and tested for binding affinity at cloned human α(1a)-, α(1b)-and α(1d)-adrenoreceptor (α(1a)-, α(1b)-and α(1d)-AR) and at native rat 5-HT(1A) receptor and for antagonist affinity at α(1A)-, α(1B)-and α(1D)-AR and at α(2A/D)-AR. Among the selected 8-substituents, namely fluorine, chlorine, methoxyl and hydroxyl, only the last caused significant decrease of α(1) binding affinity in comparison with the lead compound. Functional tests on the S isomers confirmed the detrimental effect of OH positioned in proximity to benzodioxane O(1). For the other three substituents (F, Cl, OMe), the α(1A) and the α(1D) antagonist affinities were generally lower than the α(1a) and α(1d) binding affinities, but not the α(1B) antagonist affinity, which was similar and sensibly higher compared to α(1b) binding affinity in the case of F and OMe respectively. This trend confers significant α(1B)-AR selectivity, in particular, to the 8-methoxy analogue of (S)-WB4101, a new potent (pA(2) 9.58) α(1B)-AR antagonist. The S enantiomers of all the tested compounds were proved to act as α(1)-AR inverse agonists in a vascular model.

Absolute configuration and biological profile of two thiazinooxadiazol-3-ones with L-type calcium channel activity: a study of the structural effects

In the framework of our interest in racemic thiazinooxadiazol-3-ones we determined the absolute configuration and the biological activity as L-type calcium channel blockers of two compounds that differ in the length of the acetal chain, which could affect the pharmacological profile. We observed an interesting inversion of the stereoselectivity, with the activity residing on the R-form for a short chain compound (n = 1) and on the S-form for a long chain one (n = 12). The length of the linear acetal chain appears to be able to invert the stereoselectivity of such a class of compounds, and in silico simulations suggested that this different behaviour might be explained by different hydrophilic and hydrophobic interactions with the binding site.

Cystic fibrosis: a new target for 4-Imidazo[2,1-b]thiazole-1,4-dihydropyridines

The pharmacology of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel has attracted significant interest in recent years with the aim to search for rational new therapies for diseases caused by CFTR malfunction. Mutations that abolish the function of CFTR cause the life-threatening genetic disease cystic fibrosis (CF). The most common cause of CF is the deletion of phenylalanine 508 (ΔF508) in the CFTR chloride channel. Felodipine, nifedipine, and other antihypertensive 1,4-dihydropyridines (1,4-DHPs) that block L-type Ca(2+) channels are also effective potentiators of CFTR gating, able to correct the defective activity of ΔF508 and other CFTR mutants ( Mol. Pharmacol. 2005 , 68 , 1736 ). For this purpose, we evaluated the ability of the previously and newly synthesized 4-imidazo[2,1-b]thiazoles-1,4-dihydropyridines without vascular activity and inotropic and/or chronotropic cardiac effects ( J. Med. Chem. 2008 , 51 , 1592 ) to enhance the activity of ΔF508-CFTR. Our studies indicate compounds 17, 18, 20, 21, 38, and 39 as 1,4-DHPs with an interesting profile of activity.