Novel PLGA-encapsulated-nanopiperine promotes synergistic interaction of p53/PARP-1/Hsp90 axis to combat ALX-induced-hyperglycemia.

The present study predicts the molecular targets and druglike properties of the phyto-compound piperine (PIP) by in silico studies including molecular docking simulation, druglikeness prediction and ADME analysis for prospective therapeutic benefits against diabetic complications. PIP was encapsulated in biodegradable polymer poly-lactide-co-glycolide (PLGA) to form nanopiperine (NPIP) and their physico-chemical properties were characterized by AFM and DLS. ∼ 30 nm sized NPIP showed 86.68% encapsulation efficiency and - 6 mV zeta potential, demonstrated great interactive stability and binding with CT-DNA displaying upsurge in molar ellipticity during CD spectroscopy. NPIP lowered glucose levels in peripheral circulation by > 65 mg/dL compared to disease model and improved glucose influx in alloxan-induced in vivo and in vitro diabetes models concerted with 3-folds decrease in ROS production, ROS-induced DNA damage and 27.24% decrease in nuclear condensation. The 25% increase in % cell viability and inhibition in chromosome aberration justified the initiation of p53 and PARP DNA repairing protein expression and maintenance of Hsp90. Thus, the experimental study corroborated well with in silico predictions of modulating the p53/PARP-1/Hsp90 axis, with predicted dock score value of - 8.72, - 8.57, - 8.76 kcal/mol respectively, validated docking-based preventive approaches for unravelling the intricacies of molecular signalling and nano-drug efficacy as therapeutics for diabetics.

Biodegradation of the methylenedioxyphenyl group in piperine and its derivatives: discovery of a novel methylenetransferase in an actinomycete.

IMPORTANCE: Pepper is a spice that has been used worldwide since the Age of Discovery. The substance that is responsible for the spiciness in pepper is piperine, a type of alkaloid. It has never been reported how piperine is degraded by microorganisms. In this study, we discovered a bacterium in the soil that is capable of catabolizing piperine as its sole nitrogen source. Furthermore, we discovered the enzyme involved in piperine metabolism. This enzyme decomposed the methylenedioxyphenyl group, which is the common structure in various plant-derived bioactive compounds such as sesamin, piperonal, safrole, and berberin. By utilizing this enzyme, piperine can be converted into a useful antioxidant compound. The findings about previously unknown metabolic pathways in nature can lead to the discovery of new enzymes and provide methods for the enzymatic synthesis of useful compounds.

Binding behavior and antioxidant study of spice extract piperine with respect to meat myoglobin.

It has been reported in many studies that piperine (PIP) has multiple activity properties, the most prominent of which is antioxidant activity. This work reports the binding behavior and antioxidant activity of the spice extract piperine towards myoglobin (Mb) using spectroscopic and fluorescence spectra analysis, and computational approaches. Antioxidant activity studies have shown that the antioxidant effect of the Mb-PIP complex system depends on the concentration of PIP added. An appropriate concentration of PIP can successfully prevent the release of free iron from Mb. The fluorescence results indicated that the binding of PIP to Mb was via static quenching. After binding to PIP, the α-helix content of Mb decreased by about 5%. Synchronous fluorescence results indicate that PIP is closer to Trp, and MD simulations also demonstrate that PIP enters the hydrophobic cavity of Mb and binds stably. This explains the structural changes in proteins that lead to changes in antioxidant properties. The results of this study provide a reference for the quality control of additives of plant origin in the processing and storage of meat and meat products.

Extraction, Characterization, and Evaluation of the Cytotoxic Activity of Piperine in Its Isolated form and in Combination with Chemotherapeutics against Gastric Cancer.

Gastric cancer is one of the most frequent types of neoplasms worldwide, usually presenting as aggressive and difficult-to-manage tumors. The search for new structures with anticancer potential encompasses a vast research field in which natural products arise as promising alternatives. In this scenario, piperine, an alkaloid of the Piper species, has received attention due to its biological activity, including anticancer attributes. The present work proposes three heating-independent, reliable, low-cost, and selective methods for obtaining piperine from Piper nigrum L. (Black pepper). Electronic (SEM) and optical microscopies, X-ray diffraction, nuclear magnetic resonance spectroscopies (13C and 1H NMR), and optical spectroscopies (UV-Vis, photoluminescence, and FTIR) confirm the obtention of piperine crystals. The MTT assay reveals that the piperine samples exhibit good cytotoxic activity against primary and metastasis models of gastric cancer cell lines from the Brazilian Amazon. The samples showed selective cytotoxicity on the evaluated models, revealing higher effectiveness in cells bearing a higher degree of aggressiveness. Moreover, the investigated piperine crystals demonstrated the ability to act as a good cytotoxicity enhancer when combined with traditional chemotherapeutics (5-FU and GEM), allowing the drugs to achieve the same cytotoxic effect in cells employing lower concentrations. These results establish piperine as a promising molecule for therapy investigations in aggressive gastric cancer, both in its isolated form or as a bioenhancer.

A cell-based electrochemical taste sensor for detection of Hydroxy-α-sanshool.

The Transient Receptor Potential Vanilloid 1 (TRPV1) has been identified as a suitable candidate for a spicy taste (Zanthoxylum plant) sensor. In this study, we investigated the response of TRPV1 expressed on human HepG2 cell membranes following stimulation with Hydroxy-α-sanshool. A three-dimensional (3D) cell-based electrochemical sensor was fabricated by layering cells expressing hTRPV1. l-cysteine/AuNFs electrodes were functionalized on indium tin oxide-coated glass (ITO) to enhance the sensor's selectivity and sensitivity. HepG2 cells were encapsulated in sodium alginate/gelatin hydrogel to create a 3D cell cultivation system, which was immobilized on the l-cysteine/AuNFs/ITO to serve as biorecognition elements. Using differential pulse voltammetry (DPV), the developed biosensor was utilized to detect Hydroxy-α-sanshool, a representative substance in Zanthoxylum bungeanum Maxim. The result obtained from DPV was linear with Hydroxy-α-sanshool concentrations ranging from 0 to 70 µmol/L, with a detection limit of 2.23 µmol/L. This biosensor provides a sensitive and novel macroscopic approach for TRPV1 detection.

Overview of Piperine: Bioactivities, Total Synthesis, Structural Modification, and Structure-Activity Relationships.

Natural products are an invaluable source for the discovery of drug and pesticide candidates. Piperine, a simple and pungent alkaloid, is isolated from several plants of Piperaceae. Piperine and its derivatives displayed a wide range of biological properties, such as antitumor activity, anti-inflammatory activity, antioxidant activity, neuroprotective activity, insecticidal activity, etc. In recent years, lots of works focused on the biological activities, mechanisms of action, total synthesis, and structural modifications of piperine and its derivatives have been conducted. To the best of our knowledge, however, few review articles related to the biological activities, mechanisms of action, total synthesis, and structural modifications of piperine and its derivatives have been reported to date. Therefore, this review summarizes the research advances (from 2014 to 2020) of piperine and its derivatives regarding bioactivity, mechanisms of action, total synthesis, and structural modifications. Meanwhile, the structure-activity relationships of piperine and its derivatives are also discussed.

The potential role of Piper guineense (black pepper) in managing geriatric brain aging: a review.

Brain aging is one of the unavoidable aspects of geriatric life. As one ages, changes such as the shrinking of certain parts (particularly the frontal cortex, which is vital to learning and other complex mental activities) of the brain may occur. Consequently, communications between neurons are less effective, and blood flow to the brain could also decrease. Efforts made at the biological level for repair become inadequate, leading to the accumulation of ß-amyloid peptide in the brain faster than its probable degradation mechanism, resulting in cognitive malfunction. Subsequent clinical usage of drugs in battling related brain-aging ailments has been associated with several undesirable side effects. However, recent research has investigated the potential use of natural compounds from food in combating such occurrences. This review provides information about the use of Piper guineense (black pepper) as a possible agent in managing brain aging because of its implications for practical brain function. P. guineense contains an alkaloid (piperine) reported to be an antioxidant, anti-depressant, and central nervous system stimulant. This alkaloid and other related compounds are neuroprotective agents that reduce lipid oxidation and inhibit tangles in the brain tissues.

Binding mechanism and antioxidant activity of piperine to hemoglobin.

Piperine (PIP) is the most active main component in pepper. The interaction of small molecules with biomolecules leads to structural and functional changes. In this study, the binding mechanism and antioxidant activity of PIP with hemoglobin (Hb) are presented using spectroscopic and computational methods. Results showed that the redox activity of PIP on Hb showed concentration dependence. Fluorescence and isothermal titration calorimetric experiments showed that the Hb-PIP system had a static quenching mechanism at a single binding site. The addition of PIP caused a slight perturbation to the secondary structure of Hb by structural analysis. The structural stability of the Hb-PIP binding system was demonstrated by molecular dynamics simulations, and molecular docking and thermodynamic constants confirmed that the electrostatic interaction force was dominant in the energy contribution of the system. Research results are conducive to the potential use of PIP in related meat products.

Semi-Synthesis of N-Aryl Amide Analogs of Piperine from Piper nigrum and Evaluation of Their Antitrypanosomal, Antimalarial, and Anti-SARS-CoV-2 Main Protease Activities.

Piper nigrum, or black pepper, produces piperine, an alkaloid that has diverse pharmacological activities. In this study, N-aryl amide piperine analogs were prepared by semi-synthesis involving the saponification of piperine (1) to yield piperic acid (2) followed by esterification to obtain compounds 3, 4, and 5. The compounds were examined for their antitrypanosomal, antimalarial, and anti-SARS-CoV-2 main protease activities. The new 2,5-dimethoxy-substituted phenyl piperamide 5 exhibited the most robust biological activities with no cytotoxicity against mammalian cell lines, Vero and Vero E6, as compared to the other compounds in this series. Its half-maximal inhibitory concentration (IC50) for antitrypanosomal activity against Trypanosoma brucei rhodesiense was 15.46 ± 3.09 µM, and its antimalarial activity against the 3D7 strain of Plasmodium falciparum was 24.55 ± 1.91 µM, which were fourfold and fivefold more potent, respectively, than the activities of piperine. Interestingly, compound 5 inhibited the activity of 3C-like main protease (3CLPro) toward anti-SARS-CoV-2 activity at the IC50 of 106.9 ± 1.2 µM, which was threefold more potent than the activity of rutin. Docking and molecular dynamic simulation indicated that the potential binding of 5 in the 3CLpro active site had the improved binding interaction and stability. Therefore, new aryl amide analogs of piperine 5 should be investigated further as a promising anti-infective agent against human African trypanosomiasis, malaria, and COVID-19.

The effects of drying methods and harvest season on piperine, essential oil composition, and multi-elemental composition of black pepper.

This study aimed to evaluate the piperine content, essential oil composition, and multi-elemental composition of black pepper samples according to different drying methods and harvest season. Differences in essential oil composition and B, Ca, K, Mg, and S were noted according to sampling campaign, indicating secondary metabolism plant alterations. Mechanical drying resulted in essential oil composition changes due to high temperature exposure during processing. Increases in Fe and Cr contents when employing mechanical dryers with direct heating were also observed, due to direct contact with metallic structures and particulate material from the burning process. The As and Pb contents of several samples were higher than the maximum permissible limits, reaching 0.46 and 0.56 mg kg-1, respectively, thus surpassing legislation safety limitations for human consumption.

Evaluation of Piperine as Natural Coformer for Eutectics Preparation of Drugs Used in the Treatment of Cardiovascular Diseases.

Piperine (PIP) was evaluated as a natural coformer in the preparation of multicomponent organic materials for enhancing solubility and dissolution rate of the poorly water-soluble drugs: curcumin (CUR), lovastatin (LOV), and irbesartan (IBS). A screening based on liquid assisted grinding technique was performed using 1:1 drug-PIP molar ratio mixtures, followed by differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) analyses. Three eutectic mixtures (EMs) composed of CUR-PIP, LOV-PIP, and IBS-PIP were obtained. Therefore, binary phase and Tamman's diagrams were constructed for each system to obtain the exact eutectic composition, which was 0.41:0.59, 0.29:0.71, and 0.31:0.69 for CUR-PIP, LOV-PIP, and IBS-PIP, respectively. Further, bulk materials of each system were prepared to characterize them through DSC, PXRD fully, Fourier transform infrared spectroscopy (FT-IR), and solution-state nuclear magnetic resonance (NMR) spectroscopy. In addition, the contact angle, solubility, and dissolution rate of each system were evaluated. The preserved characteristic in the PXRD patterns and FT-IR spectra of the bulk material of each system confirmed the formation of EM mixture without molecular interaction in solid-state. The formation of EM resulted in improved aqueous solubility and dissolution rate associated with the increased wettability observed by the decrease in contact angle. In addition, solution NMR analyses of CUR-PIP, LOV-PIP, and IBS-PIP suggested no significant intermolecular interactions in solution between the components of the EM. Hence, this study concludes that PIP could be an effective coformer to improve the solubility and dissolution rate of CUR, LOV, and IBS.

A critical review on the extraction and pharmacotherapeutic activity of piperine.

Black pepper (Piper nigrum L.) is a climbing perennial plant in the Piperaceae family. Pepper has been known since antiquity for its use both as a medicine and a spice. It is particularly valued for its pungency attributed to its principal constituent - piperine. This review summarizes the information on the biological source of piperine, its extraction and isolation strategies, physicochemical properties, and pharmacological activity - analgesic, immunomodulatory, anti-depressive, anti-diarrheal, hepatoprotective, etc. The effect of piperine on biotransformation of co-administered drugs is also presented in this review, along with the mechanisms involved in its bioavailability-enhancing effect. Its important medicinal uses, including anti-hepatotoxic, anti-diarrheal, anti-depressive, analgesic, and immunomodulatory effects, besides many other traditional uses, are compiled. Based on an exhaustive review of literature, it may be concluded that piperine is a very promising alkaloid found in members of the Piperaceae family.

Rapid estimation of piperine in black pepper: Exploration of Raman spectroscopy.

INTRODUCTION: The major chemical marker of black pepper (Piper nigrum L) is piperine and its estimation is extremely important for quality assessment of black pepper. The methods for piperine quantification, to date, are laboratory based and use high end instruments like chromatographs, which require tedious sample processing and cause sample destruction. OBJECTIVES: In this article, we present a simple, rapid and green analytical method based on Raman spectroscopy for the quantitative assessment of piperine. MATERIAL AND METHODS: To assess the potential of the technique, we report the complete vibrational characterisation of the piperine with density functional theory (DFT) calculations. RESULTS: The theoretical peaks were obtained at 1097 cm-1 , 1388 cm-1 , 1528 cm-1 , 1578 cm-1 , and at 1627 cm-1 , and this result was verified in a Raman spectrometer followed by a preliminary experiment. Twenty black pepper samples were analysed using high-performance liquid chromatography (HPLC) and used as reference data for Raman analysis. The Raman shift spectra were analysed using partial least squares (PLS) and good prediction accuracy with correlation coefficient of prediction (Rp2 ) = 0.93, root mean square error of prediction (RMSEP) = 0.13 and residual prediction deviation (RPD) = 3.9 obtained. CONCLUSIONS: The results demonstrate the efficacy of the Raman technique for the estimation of piperine in the dry fruit of Piper nigrum.

Natural inspired piperine-based ureas and amides as novel antitumor agents towards breast cancer.

In this work, the natural piperine moiety was utilised to develop two sets of piperine-based amides (5a-i) and ureas (8a-y) as potential anticancer agents. The anticancer action was assessed against triple negative breast cancer (TNBC) MDA-MB-231, ovarian A2780CP and hepatocellular HepG2 cancer cell lines. In particular, 8q stood out as the most potent anti-proliferative analogue against TNBC MDA-MB-231 cells with IC50 equals 18.7 µM, which is better than that of piperine (IC50 = 47.8 µM) and 5-FU (IC50 = 38.5 µM). Furthermore, 8q was investigated for its possible mechanism of action in MDA-MB-231 cells via Annexin V-FITC apoptosis assay and cell cycle analysis. Moreover, an in-silico analysis has proposed VEGFR-2 as a probable enzymatic target for piperine-based derivatives, and then has explored the binding interactions within VEGFR-2 active site (PDB:4ASD). Finally, an in vitro VEGFR-2 inhibition assay was performed to validate the in silico findings, where 8q showed good VEGFR-2 inhibitory activity with IC50 = 231 nM.

Proangiogenic Effect of Affinin and an Ethanolic Extract from Heliopsis longipes Roots: Ex Vivo and In Vivo Evidence.

Angiogenesis, the formation of new blood vessels, underlies tissue development and repair. Some medicinal plant-derived compounds can modulate the angiogenic response. Heliopsis longipes, a Mexican medicinal plant, is widely used because of its effects on pain and inflammation. The main bioactive phytochemicals from H. longipes roots are alkamides, where affinin is the most abundant. Scientific studies show various medical effects of organic extracts of H. longipes roots and affinin that share some molecular pathways with the angiogenesis process, with the vasodilation mechanism of action being the most recent. This study investigates whether pure affinin and the ethanolic extract from Heliopsis longipes roots (HLEE) promote angiogenesis. Using the aortic ring rat assay (ex vivo method) and the direct in vivo angiogenesis assay, where angioreactors were implanted in CD1 female mice, showed that affinin and the HLEE increased vascular growth in a dose-dependent manner in both bioassays. This is the first study showing the proangiogenic effect of H. longipes. Further studies should focus on the mechanism of action and its possible therapeutic use in diseases characterized by insufficient angiogenesis.

Piperine analogs arrest c-myc gene leading to downregulation of transcription for targeting cancer.

G-quadruplex (G4) structures are considered a promising therapeutic target in cancer. Since Ayurveda, Piperine has been known for its medicinal properties. Piperine shows anticancer properties by stabilizing the G4 motif present upstream of the c-myc gene. This gene belongs to a group of proto-oncogenes, and its aberrant transcription drives tumorigenesis. The transcriptional regulation of the c-myc gene is an interesting approach for anticancer drug design. The present study employed a chemical similarity approach to identify Piperine similar compounds and analyzed their interaction with cancer-associated G-quadruplex motifs. Among all Piperine analogs, PIP-2 exhibited strong selectivity, specificity, and affinity towards c-myc G4 DNA as elaborated through biophysical studies such as fluorescence emission, isothermal calorimetry, and circular dichroism. Moreover, our biophysical observations are supported by molecular dynamics analysis and cellular-based studies. Our study showed that PIP-2 showed higher toxicity against the A549 lung cancer cell line but lower toxicity towards normal HEK 293 cells, indicating increased efficacy of the drug at the cellular level. Biological evaluation assays such as TFP reporter assay, quantitative real-time PCR (qRT- PCR), and western blotting suggest that the Piperine analog-2 (PIP-2) stabilizes the G-quadruplex motif located at the promoter site of c-myc oncogene and downregulates its expression. In conclusion, Piperine analog PIP-2 may be used as anticancer therapeutics as it affects the c-myc oncogene expression via G-quadruplex mediated mechanism.

New Pyridone-Based Derivatives as Cannabinoid Receptor Type 2 Agonists.

The activation of the human cannabinoid receptor type II (CB2R) is known to mediate analgesic and anti-inflammatory processes without the central adverse effects related to cannabinoid receptor type I (CB1R). In this work we describe the synthesis and evaluation of a novel series of N-aryl-2-pyridone-3-carboxamide derivatives tested as human cannabinoid receptor type II (CB2R) agonists. Different cycloalkanes linked to the N-aryl pyridone by an amide group displayed CB2R agonist activity as determined by intracellular [cAMP] levels. The most promising compound 8d exhibited a non-toxic profile and similar potency (EC50 = 112 nM) to endogenous agonists Anandamide (AEA) and 2-Arachidonoylglycerol (2-AG) providing new information for the development of small molecules activating CB2R. Molecular docking studies showed a binding pose consistent with two structurally different agonists WIN-55212-2 and AM12033 and suggested structural requirements on the pyridone substituents that can satisfy the orthosteric pocket and induce an agonist response. Our results provide additional evidence to support the 2-pyridone ring as a suitable scaffold for the design of CB2R agonists and represent a starting point for further optimization and development of novel compounds for the treatment of pain and inflammation.

Fatty ethanolamide of Bertholletia excelsa triglycerides (Brazil nuts): anti-inflammatory action and acute toxicity evaluation in Zebrafish (Danio rerio).

Fatty amides (N-alkylamides) are bioactive lipids that are widely distributed in microorganisms, animals, and plants. The low yield in the extraction process of spilantol, a fatty amide, which is mainly related to its diverse biological effects, compromises its application on a large scale. Thus, this study proposes an alternative method to synthesise fatty amides from Bertholletia excelsa (AGBe) oil, with a chemical structure similar to that of spilantol. Carrageenan-induced abdominal oedema in vivo models were used in zebrafish (Danio rerio). In in vivo studies, oral AGBe produced no signs of toxicity. In the histopathological study, AGBe did not cause significant changes in the main metabolising organs (liver, kidneys, and intestines). All doses of AGBe (100 mg/kg, 500 mg/kg, and 750 mg/kg) were effective in reducing oedema by 65%, 69%, and 95%, respectively, producing a dose-response effect compared to the control group, and spilantol-inhibited oedema by 48%. In the in silico study, with the use of molecular docking, it was observed that among the AGBe, the molecules 18:1, ω-7-ethanolamine, and 18:1, ω-9-ethanolamine stood out, with 21 interactions for COX-2 and 20 interactions for PLA2, respectively, surpassing the spilantol standard with 15 interactions for COX-2 and PLA2. The anti-inflammatory action hypothesis was confirmed in the in silico study, demonstrating the involvement of AGBe in the process of inhibiting the enzymes COX-2 and PLA2. Therefore, based on all the results obtained and the fact that until the dose of 1000 mg/kg was administered orally in zebrafish, it was not possible to determine the LD50; it can be said that AGBe is effective and safe for anti-inflammatory activity.

Prediction of essential binding domains for the endocannabinoid N-arachidonoylethanolamine (AEA) in the brain cannabinoid CB1 receptor.

Δ9-tetrahydrocannabinol (Δ9-THC), the main active ingredient of Cannabis sativa (marijuana), interacts with the human brain cannabinoid (CB1) receptor and mimics pharmacological effects of endocannabinoids (eCBs) like N-arachidonylethanolamide (AEA). Due to its flexible nature of AEA structure with more than 15 rotatable bonds, establishing its binding mode to the CB1 receptor is elusive. The aim of the present study was to explore possible binding conformations of AEA within the binding pocket of the CB1 receptor confirmed in the recently available X-ray crystal structures of the CB1 receptor and predict essential AEA binding domains. We performed long time molecular dynamics (MD) simulations of plausible AEA docking poses until its receptor binding interactions became optimally established. Our simulation results revealed that AEA favors to bind to the hydrophobic channel (HC) of the CB1 receptor, suggesting that HC holds essential significance in AEA binding to the CB1 receptor. Our results also suggest that the Helix 2 (H2)/H3 region of the CB1 receptor is an AEA binding subsite privileged over the H7 region.

Formulation of Piperine-Chitosan-Coated Liposomes: Characterization and In Vitro Cytotoxic Evaluation.

The present research work is designed to prepare and evaluate piperine liposomes and piperine-chitosan-coated liposomes for oral delivery. Piperine (PPN) is a water-insoluble bioactive compound used for different diseases. The prepared formulations were evaluated for physicochemical study, mucoadhesive study, permeation study and in vitro cytotoxic study using the MCF7 breast cancer cell line. Piperine-loaded liposomes (PLF) were prepared by the thin-film evaporation method. The selected liposomes were coated with chitosan (PLFC) by electrostatic deposition to enhance the mucoadhesive property and in vitro therapeutic efficacy. Based on the findings of the study, the prepared PPN liposomes (PLF3) and chitosan coated PPN liposomes (PLF3C1) showed a nanometric size range of 165.7 ± 7.4 to 243.4 ± 7.5, a narrow polydispersity index (>0.3) and zeta potential (-7.1 to 29.8 mV). The average encapsulation efficiency was found to be between 60 and 80% for all prepared formulations. The drug release and permeation study profile showed biphasic release behavior and enhanced PPN permeation. The in vitro antioxidant study results showed a comparable antioxidant activity with pure PPN. The anticancer study depicted that the cell viability assay of tested PLF3C2 has significantly (p < 0.001)) reduced the IC50 when compared with pure PPN. The study revealed that oral chitosan-coated liposomes are a promising delivery system for the PPN and can increase the therapeutic efficacy against the breast cancer cell line.