Elucidation on the In Vivo Activity of the Bivalent Opioid Peptide MACE2 against Several Types of Chronic Pain.

Biphalin is a bivalent μ/δ opioid receptor agonist showing a promising therapeutic profile with reduced side effects, but as a peptide is limited by poor metabolic stability and blood-brain barrier penetration. To improve these features, we developed the ligand and showed initial in vivo efficacy. To further explore the druggability of this ligand, in this report, we tested metabolic stability in human plasma, receptor engagement by 3 different routes of administration using the tail-flick test, and efficacy in 2 different pathological and chronic pain models.

Anti-Inflammatory and Antinociceptive Properties of the Quercetin-3-Oleate AV2, a Novel FFAR1 Partial Agonist.

Free fatty acid receptor 1 (FFAR1) has emerged as the most targeted isoform of the free fatty acid receptors because of its involvement in the modulation of energy balance and its potential role in the control of inflammatory and pain conditions. Quercetin-3-oleate (AV2), recognized as a new FFAR1 partial agonist, was investigated for its ability to modulate inflammation and nociception. Human immortal neuroblastoma SH and the murine macrophagic RAW 264.

A reverse translational approach reveals the protective roles of Mangifera indica in inflammatory bowel disease.

Inflammatory bowel diseases (IBDs) are chronic intestinal disorders often characterized by a dysregulation of T cells, specifically T helper (Th) 1, 17 and T regulatory (Treg) repertoire. Increasing evidence demonstrates that dietary polyphenols from Mangifera indica L. extract (MIE, commonly known as mango) mitigate intestinal inflammation and splenic Th17/Treg ratio.

New biologic (Ab-IPL-IL-17) for IL-17-mediated diseases: identification of the bioactive sequence (nIL-17) for IL-17A/F function.

Objectives: Interleukin (IL) 17s cytokines are key drivers of inflammation that are functionally dysregulated in several human immune-mediated inflammatory diseases (IMIDs), such as rheumatoid arthritis (RA), psoriasis and inflammatory bowel disease (IBD). Targeting these cytokines has some therapeutic benefits, but issues associated with low therapeutic efficacy and immunogenicity for subgroups of patients or IMIDs reduce their clinical use. Therefore, there is an urgent need to improve the coverage and efficacy of antibodies targeting IL-17A and/or IL-17F and IL-17A/F heterodimer.

Rimonabant-Based Compounds Bearing Hydrophobic Amino Acid Derivatives as Cannabinoid Receptor Subtype 1 Ligands.

In this study, 1-pyrazole-3-carboxylic acids related to the cannabinoid type 1 (CB1) receptor antagonist rimonabant were amidated with valine or -leucine, and the resulting acids were further diversified as methyl esters, amides, and -methyl amides. receptor binding and functional assays demonstrated a wide series of activities related to the CB1 receptors (CB1Rs). Compound showed a high CB1R binding affinity ( = 6.

Food-inspired peptides from spinach Rubisco endowed with antioxidant, antinociceptive and anti-inflammatory properties.

Rubiscolin-6 (amino acid sequence: YPLDLF) is a selective δ-opioid receptor peptide isolated from spinach Rubisco. Its synthetic analogue, peptide YPMDIV is the most potent described so far for its increased opioid activity, thus in this work it was considered as for the design of twelve new analogues . Firstly all the novel compounds have been tested for their antinociceptive and anti-inflammatory capacity and in order to evaluate their ability to maintain or loss the original activity.

Design of Analgesic Trivalent Peptides with Low Withdrawal Symptoms: Probing the Antinociceptive Profile of Novel Linear and Cyclic Peptides as Opioid Pan Ligands.

The discovery of efficacious and safe analgesics with reduced side effects is the foremost challenge in the pain field. In this work, we report the and evaluation of linear and cyclic analogues of biphalin with the aim to complete the series of structural modifications previously applied in the development of opioid peptides incorporating a xylene bridge. Replacement of Tyr by Dmt (2,5-dimethyltyrosine) in the linear biphalin analogue and cyclic analogue resulted in two new compounds (namely, and ) endowed with improved KOR/MOR/DOR binding affinity.

Discovery of κ Opioid Receptor (KOR)-Selective d-Tetrapeptides with Improved Antinociceptive Effect after Peripheral Administration.

Peripherally active tetrapeptides as selective κ opioid receptor (KOR) agonists have been prepared in good overall yields and high purity following solid-phase peptide synthesis via Fmoc protection strategy. Structural modifications at the first and second position of the FF(d-Nle)R-NH () were contemplated with aromatic side chains containing d-amino acids, such as (d)-F-Phe, (d)-F-Phe, (d)-F-Phe, which led to highly selective and efficacious KOR agonists endowed with strong antinociceptive activity following intravenous (i.v.

A Study on Chemical Characterization and Biological Abilities of Extracts Obtained by Different Techniques.

In the quest for novel therapeutic agents from plants, the choice of extraction solvent and technique plays a key role. In this study, the possible differences in the phytochemical profile and bioactivity (antioxidant and enzyme inhibitory activity) of the leaves and stem bark extracted using water, ethyl acetate and methanol, and different techniques, namely infusion, maceration and Soxhlet extraction, were investigated. Data collected showed that methanol extracts of both leaves (48.

Synthesis, Biological Activity and Molecular Docking of Chimeric Peptides Targeting Opioid and NOP Receptors.

Recently, mixed opioid/NOP agonists came to the spotlight for their favorable functional profiles and promising outcomes in clinical trials as novel analgesics. This study reports on two novel chimeric peptides incorporating the fragment Tyr-c[D-Lys-Phe-Phe]Asp-NH (), a cyclic peptide with high affinity for µ and κ opioid receptors (or MOP and KOP, respectively), conjugated with the peptide Ac-RYYRIK-NH, a known ligand of the nociceptin/orphanin FQ receptor (NOP), yielding RP-170-RYYRIK-NH () and RP-170-Gly-RYYRIK-NH (). In vitro, the chimeric gained affinity for KOP, hence becoming a dual KOP/MOP agonist, while behaved as a mixed MOP/NOP agonist with low nM affinity.

A Comparative Study on Phytochemical Fingerprint of Two Diverse Tondino del Tavo and Cannellino Bio Extracts.

Common bean () represents one of the most famous foods with antiobesity activity showing a significant efficacy against fat accumulation, insulin resistance and dyslipidaemia. In this work, two Italian varieties of common bean, i.e.

Food-Specific IgG4 Antibody-Guided Exclusion Diet Improves Conditions of Patients with Chronic Pain.

Introduction: Chronic pain is related to gastrointestinal (GI) functions because food components affect inflammation and pain through their action on the GI immune and/or neural system and because many analgesics interact with the gut to alter its structure and function. Immunoglobulin G4 (IgG4) are food-specific antibodies resulting from exposure of the gut immune system to nutrients. High IgG4 levels have been found to be associated with inflammation.

New Insights on Formyl Peptide Receptor Type 2 Involvement in Nociceptive Processes in the Spinal Cord.

Formyl peptide receptor type 2 (FPR2/ALX) belongs to the formyl peptide receptors (FPRs) family clustered on chromosome 19 and encodes a family of three Class A of G protein-coupled receptors (GPCRs). A short N-terminal region, an NPXXY motif in transmembrane (TM) region 7 and an E/DRY motif that bridges TM3 and TM6 stabilizing inactive receptor conformations characterize this class of receptors. In recognizing pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), FPRs play a crucial role in innate immune responses.

Calceolarioside A, a Phenylpropanoid Glycoside from spp., Displays Antinociceptive and Anti-Inflammatory Properties.

Phenylpropanoid glycosides are a class of natural substances of plant origin with interesting biological activities and pharmacological properties. This study reports the antinociceptive and anti-inflammatory effects of calceolarioside A, a phenylpropanoid glycoside previously isolated from various Calceolaria species. In models of acute nociception induced by thermal stimuli, such as the hot plate and tail flick test, calceolarioside administered at doses of 1, 5, and 10 μg in the left cerebral ventricles did not modify the behavioral response of mice.

Phenolic Analysis and In Vitro Biological Activity of Red Wine, Pomace and Grape Seeds Oil Derived from L. cv. Montepulciano d'Abruzzo.

Grape pomace is commonly considered a waste product of monovarietal red wine production. Methods: HPLC-DAD analysis was performed to determine the polyphenol and flavonoid contents of all the extracts obtained from Montepulciano d'Abruzzo red wine and grape skins whereas, GC-MS was applied to the determination of fatty acid composition in grape seeds oil. Biological characterization involves antioxidant and antimicrobial assays for all the extracts and seeds oil; Their ability to inhibit α-glucosidase, α-amylase, α-tyrosinase, and ChE enzymes was also detected, together with anti-inflammatory activity on wine, grape skin extracts, and seeds oil by lipoxygenase (5-LOX) and LPS-stimulated macrophage release assays.

In Silico Identification of Tripeptides as Lead Compounds for the Design of KOR Ligands.

The kappa opioid receptor (KOR) represents an attractive target for the development of drugs as potential antidepressants, anxiolytics and analgesics. A robust computational approach may guarantee a reduction in costs in the initial stages of drug discovery, novelty and accurate results. In this work, a virtual screening workflow of a library consisting of ~6 million molecules was set up, with the aim to find potential lead compounds that could manifest activity on the KOR.

Selective MOR activity of DAPEA and Endomorphin-2 analogues containing a (R)-γ-Freidinger lactam in position two.

The use of α-amino-γ lactam of Freidinger (Agl) may serve as an impressive method to increase the biological stability of peptides and an appropriate tool to elucidate their structure-activity relationships. The endomorphin-2 (EM-2) and [D-Ala, des-Leu] enkephalin amide (DAPEA) are two linear opioid tetrapeptides agonists of MOR and MOR/DOR respectively. Herein, we investigated the influence of the incorporation of (R/S)-Agl in position 2 and 3 on the biological profile of the aforementioned products in vitro and in vivo.

Ammonium Glycyrrhizinate Prevents Apoptosis and Mitochondrial Dysfunction Induced by High Glucose in SH-SY5Y Cell Line and Counteracts Neuropathic Pain in Streptozotocin-Induced Diabetic Mice.

Glycyrrhiza glabra, commonly known as liquorice, contains several bioactive compounds such as flavonoids, sterols, triterpene, and saponins; among which, glycyrrhizic acid, an oleanane-type saponin, is the most abundant component in liquorice root. Diabetic peripheral neuropathy is one of the major complications of diabetes mellitus, leading to painful condition as neuropathic pain. The pathogenetic mechanism of diabetic peripheral neuropathy is very complex, and its understanding could lead to a more suitable therapeutic strategy.

Feeding Your Himalayan Expedition: Nutritional Signatures and Body Composition Adaptations of Trekkers and Porters.

High-altitude exposure leads to many physiological challenges, such as weight loss and dehydration. However, little attention has been posed to the role of nutrition and ethnic differences. Aiming to fulfill this gap, five Italian trekkers and seven Nepalese porters, all males, recorded their diet in diaries during a Himalayan expedition (19 days), and the average daily intake of micro and macro-nutrients were calculated.

L. (Saffron) in Alzheimer's Disease Treatment: Bioactive Effects on Cognitive Impairment.

Crocus sativus L. (saffron) appears to own neuroprotective effects on cognitive impairment in patients with Alzheimer's disease (AD). The purpose of this work is to review evidence and mechanisms of saffron-induced therapeutic outcomes and measureable cognitive benefits in AD.

New insights on the arylpiperazinylalkyl pyridazinone ET1 as potent antinociceptive and anti-inflammatory agent.

Pyridazine derivatives, such as arylpiperazinylalkyl pyridazinones, display antinociceptive effects to thermal and chemical stimuli. Here, we extended our previous knowledge on the pharmacological profile of 4-amino-6-methyl-2-(3-(4-(4-methylcyclohexa-1,3-dien-1-yl)piperazin-1-yl)propyl)-5-vinylpyridazin-3(2H)-one, here referred as ET1, paving the way for the comprehension of its complete mechanism of action. To this aim, we have evaluated the mouse behavioural responses in several animal models of pain, the effect of ET1 in the murine model of zymosan-induced paw oedema and air-pouch, assessing the cytokines and the cellular phenotype and finally, an in vitro radioligand binding study was performed on a panel of 30 different receptors.

Viscum album L. homogenizer-assisted and ultrasound-assisted extracts as potential sources of bioactive compounds.

Viscum album L. (Mistletoe) is one of the most famous plants in many countries utilized for several purposes. The current study aimed to describe chemical profiles and biological activities of homogenizer-assisted extract (HAE) and ultrasound-assisted extract (UAE)) of V.

Exploring the Nutraceutical Potential of Dried Pepper L. on Market from Altino in Abruzzo Region.

Sweet pepper is a typical type of from Abruzzo region, recognized as a traditional and local product, traditionally cultivated in the town of Altino (Abruzzo region, Italy). The aim of this study is to compare the sweet type of peppers from Altino with the hot pepper cultivated in the same area, in order to delineate their different phytochemical and biological profiles in vitro and in vivo. In this study, we elucidated their phytochemical composition, fatty acids composition and phenolic/flavonoid contents in extracts.

Discovery of Kynurenines Containing Oligopeptides as Potent Opioid Receptor Agonists.

Kynurenine (kyn) and kynurenic acid (kyna) are well-defined metabolites of tryptophan catabolism collectively known as "kynurenines", which exert regulatory functions in host-microbiome signaling, immune cell response, and neuronal excitability. Kynurenine containing peptides endowed with opioid receptor activity have been isolated from natural organisms; thus, in this work, novel opioid peptide analogs incorporating L-kynurenine (L-kyn) and kynurenic acid (kyna) in place of native amino acids have been designed and synthesized with the aim to investigate the biological effect of these modifications. The kyna-containing peptide () binds selectively the m-opioid receptor with a Ki = 1.