Inhibition of 2-AG hydrolysis alleviates posttraumatic headache attributed to mild traumatic brain injury.

BACKGROUND: Posttraumatic headache (PTH) is a common and debilitating symptom following repetitive mild traumatic brain injury (rmTBI), and it mainly resembles a migraine-like phenotype. While modulation of the endocannabinoid system (ECS) is effective in treating TBI and various types of pain including migraine, the role of augmentation of endocannabinoids in treating PTH has not been investigated. METHODS: Repetitive mild TBI was induced in male C57BL/6J mice using the non-invasive close-head impact model of engineered rotational acceleration (CHIMERA). Periorbital allodynia was assessed using von Frey filaments and determined by the "Up-Down" method. Immunofluorescence staining was employed to investigate glial cell activation and calcitonin gene-related peptide (CGRP) expression in the trigeminal ganglion (TG) and trigeminal nucleus caudalis (TNC) of the rmTBI mice. Levels of 2-arachidonoyl glycerol (2-AG), anandamide (AEA), and arachidonic acid (AA) in the TG, medulla (including TNC), and periaqueductal gray (PAG) were measured by mass spectrometry. The therapeutic effect of endocannabinoid modulation on PTH was also assessed. RESULTS: The rmTBI mice exhibited significantly increased cephalic pain hypersensitivity compared to the sham controls. MJN110, a potent and selective inhibitor of the 2-AG hydrolytic enzyme monoacylglycerol lipase (MAGL), dose-dependently attenuated periorbital allodynia in the rmTBI animals. Administration of CGRP at 0.01 mg/kg reinstated periorbital allodynia in the rmTBI animals on days 33 and 45 post-injury but had no effect in the sham and MJN110 treatment groups. Activation of glial cells along with increased production of CGRP in the TG and TNC at 7 and 14 days post-rmTBI were attenuated by MJN110 treatment. The anti-inflammatory and anti-nociceptive effects of MJN110 were partially mediated by cannabinoid receptor activation, and the pain-suppressive effect of MJN110 was completely blocked by co-administration of DO34, an inhibitor of 2-AG synthase. The levels of 2-AG in TG, TNC and PAG were decreased in TBI animals, significantly elevated and further reduced by the selective inhibitors of 2-AG hydrolytic and synthetic enzymes, respectively. CONCLUSION: Enhancing endogenous levels of 2-AG appears to be an effective strategy for the treatment of PTH by attenuating pain initiation and transmission in the trigeminal pathway and facilitating descending pain inhibitory modulation.

Anandamide modulation of monocyte-derived Langerhans cells: implications for immune homeostasis and skin inflammation.

Introduction: The endocannabinoid system (ECS), named after the chemical compounds found in the cannabis plant, is a regulatory network of neurotransmitters, receptors, and enzymes that plays crucial roles in skin health and disease. Endogenous ligands of the ECS, called endocannabinoids, have proven to be important regulators of immune responses. One of the most prevalent endocannabinoids, arachidonoylethanolamide (also known as anandamide), is known for its anti-inflammatory effects. Langerhans cells (LCs) are the sole antigen-presenting cells present in the human epidermis. They serve as the first line of defense against pathogens and are essential for the skin's specific immune responses and play a critical role in maintaining tissue homeostasis; however, little is known about the effect of endocannabinoids on these cells. Our research aimed to provide the connection between monocyte-derived Langerhans cells (moLCs) and the ECS, shedding light on their collaborative roles in immune homeostasis and inflammation. Methods: Human monocytes were differentiated into moLCs using established protocols. Anandamide was applied during the differentiation process to test its effect on the viability, marker expression, and cytokine production of the cells, as well as in short term treatments for intracellular calcium measurement. TLR ligands applied after the differentiation protocol were used to activate moLCs. The impact of anandamide on the functionality of moLCs was further assessed using differential gene expression analysis of bulk RNA-Seq data, moLC-T cell cocultures, while ELISpot was employed to determine polarization of T cells activated in the aforementioned cocultures. Results: Anandamide did not significantly affect the viability of moLCs up to 10 µM. When applied during the differentiation process it had only a negligible effect on CD207 expression, the prototypic marker of LCs; however, there was an observed reduction in CD1a expression by moLCs. Anandamide had no significant effects on the maturation status of moLCs, nor did it affect the maturation induced by TLR3 and TLR7/8 agonists. MoLCs differentiated in the presence of anandamide did however show decreased production of CXCL8, IL-6, IL-10 and IL-12 cytokines induced by TLR3 and TLR7/8 activation. Anandamide-treated moLCs showed an increased capability to activate naïve T cells; however, not to the level seen with combined TLR agonism. RNA sequencing analysis of moLCs differentiated with anandamide showed modest changes compared to control cells but did reveal an inhibitory effect on oxidative phosphorylation specifically in activated moLCs. Anandamide also promoted the polarization of naïve T cells towards a Th1 phenotype. Discussion: Our results show that anandamide has nuanced effects on the differentiation, maturation, cytokine secretion, metabolism and function of activated moLCs. Among these changes the decrease in CD1a expression on moLCs holds promise to selectively dampen inflammation induced by CD1a restricted T cells, which have been implicated as drivers of inflammation in common inflammatory skin conditions such as psoriasis, atopic dermatitis and contact dermatitis.

Investigation of the effects of curcumin and piperine on cyclophosphamide-induced brain injury in rats.

Cyclophosphamide (CP) is an antineoplastic drug widely used in chemotherapy. Curcumin (CUR) and piperine (PP) show a protective effect on neurodegenerative and neurological diseases. This research was designed to measure several biochemical parameters in the brain tissue of CP-applied rats to investigate the impact of combined CUR-PP administration. The study evaluated six groups of eight rats: Group 1 was the control; Groups 2 and 3 were administered 200 or 300 mg/kg CUR-PP via oral gavage; Group 4 received only 200 mg/kg CP on day 1; Groups 5 and 6 received CP + CUR-PP for 7 days. Data from all parameters indicated that CP caused brain damage. Phosphorylated TAU (pTAU), amyloid-beta peptide 1-42 (Aß1-42), glutamate (GLU), and gamma amino butyric acid (GABA) parameters were the same in Groups 4, 5, and 6. On the other hand, 8-hydroxy-2-deoxyguanosine (8-OHdG), nitric oxide (NO), interleukin-6 (IL-6), nuclear factor kappa beta (NF-kß), malondialdehyde (MDA), and tumor necrosis factor-alpha (TNF-α) levels in the CP + CUR-PP groups were lower than those in the CP group (p < 0.05). However, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and reduced glutathione (GSH) parameters were higher in the CP + CUR-PP groups compared to the CP group (p < 0.05). It is thought that the similarity of Groups 5 and 6 with Group 4 in Aß1-42, pTAU, GLU, and GABA parameters hinder the determination of treatment protection however, they might have a therapeutic effect if the applied dose or study duration were changed. This study attempted to evaluate the effects of a CUR-PP combination on CP-induced brain damage in rats by measuring biochemical parameters and performing histopathological examinations. Based on the findings, this CUR-PP combination could be considered an alternative medicine option in cases with conditions similar to those evaluated in this study.

Additive antinociceptive action of intrathecal anandamide reuptake inhibitor and morphine in the management of post-incisional pain in rats.

Spinal opioids have mixed efficacy and their adverse effects force treatment cessation of postoperative pain. Consequently, there is an ongoing search for new therapeutic strategies. Here, we evaluated the analgesic efficacy of intrathecal UCM707, an anandamide reuptake inhibitor, and morphine combination. Firstly, we assessed the effects of morphine (1, 5 and 10 µg), UCM707 (75 µg) and its combination in the hot plate. Then, morphine + UCM707 at sub-effective doses was evaluated in a rat post-incisional pain model. In addition, µ-, CB1r-, CB2r- and TRPV1-antagonists were pre-administered before the combination. Activation of µ-opioid and CB1r, and Cnr1, Cnr2, Oprm1 and TRPV1 expressions were evaluated in the lumbar sacra and periaqueductal grey by [35 S]-GTPγS binding autoradiography and qPCR studies. In the hot plate, morphine (1 µg) and UCM707 (75 µg) induced a more robust analgesic effect than each drug alone. Morphine plus UCM707 did not modify µ-opioid nor CB1 receptor function in the PAG or LS. Cnr1 and TRPV1 expression increased in the lumbar sacra (LS). Morphine plus UCM707 significantly reduced post-incisional pain at 1 and 4 days after surgery. Cnr1, Cnr2 and TRPV1 expressions increased in the LS. Blockade of µ-opioid receptor reduced combination effects on days 1 and 4. CB1r- and CB2r-antagonism reduced morphine + UCM707 effects on days 1 and 4, respectively. CB1r and TRPV1-antagonism improved their antinociceptive effects on day 4. These results revealed a synergistic/additive analgesic effect of UCM707 and morphine combination controlling postincisional pain. CB1r, CB2r and TRPV1 contribute differently as central sensitization occurs.

Effects of Combination of Curcumin and Piperine Supplementation on Glycemic Profile in Patients with Prediabetes and Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis.

Objective: This study aimed to evaluate the effects of the combination of curcumin and piperine supplementation on Fasting Plasma Glucose (FPG), Homeostatic Model of Insulin Resistance (HOMA-IR), and Body Mass Index (BMI) in patients with prediabetes and type 2 Diabetes Mellitus (T2DM). This review was done to identify potential herbal remedies that may help improve glycemic parameters, leading to better health outcomes in combination with current antidiabetic treatment. Methodology: This systematic review was based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). It was conducted in 2023 with sources and databases from MEDLINE, EBSCO-Host, ScienceDirect and ProQuest. This paper included randomized-controlled trials exploring the effects of the combination of curcumin and piperine on patients with prediabetes and T2DM. Systematic reviews, observational studies, case reports, case series, conference abstracts, book sections, commentaries/editorials, non-human studies and articles with unavailable full-text and written in non-English language, were excluded. The key terms for the literature search were "curcumin," "piperine," "prediabetes" and "Type 2 Diabetes Mellitus." We use Cochrane Risk of Bias (RoB) 2 for quality assessment of the included studies and Review Manager (RevMan) 5.4 to do the meta-analysis. Results: A total of three studies were included in this systematic review. Two studies from Neta et al., and Cicero et al., showed no significant difference in HOMA-IR, BMI and FPG levels between the curcumin, piperine and placebo groups. One study from Panahi et al. demonstrated a significant difference in BMI levels between the curcumin and piperine and placebo groups (p <0.01). The meta-analysis showed that FPG levels, HOMA-IR and BMI improved among patients with diabetes given in curcumin and piperine with reported mean differences (MD) of = -7.61, 95% CI [-15.26, 0.03], p = 0.05, MD = -0.36, 95% CI [-0.77 to 0.05], p = 0.09, and MD = -0.41, 95% CI [-0.85 to 0.03], p = 0.07, respectively). Conclusions: The supplementation of curcumin and piperine showed a numerical reduction in FPG, HOMA-IR and BMI, but were not statistically significant. Further research is needed as there is a paucity of studies included in the review.

Development of piperine nanoparticles stabilized by OSA modified starch through wet-media milling technique with enhanced anti-adipogenic effect in 3T3-L1 adipocytes.

Piperine (PIP) has been known for its pharmacological activities with low water solubility and poor dissolution, which limits its nutritional application. The purpose of this research was to enhance PIP stability, dispersibility and biological activity by preparing PIP nanoparticles using the wet-media milling approach combined with nanosuspension solidification methods of spray/freeze drying. Octenyl succinic anhydride (OSA)-modified waxy maize starch was applied as the stabilizer to suppress aggregation of PIP nanoparticles. The particle size, redispersibility, storage stability and in vitro release behavior of PIP nanoparticles were measured. The regulating effect on adipocyte differentiation was evaluated using 3T3-L1 cell model. Results showed that PIP nanoparticles had a reduced particle size of 60 ± 1 nm, increased release rate in the simulated gastric (SGF) and intestinal fluids (SIF) and enhanced inhibition effect on adipogenesis in 3T3-L1 cells compared with free PIP, indicating that PIP-loaded nanoparticles with improved stability and anti-adipogenic property were developed successfully by combining wet-media milling and drying methods.

Preparation, pungency and bioactivity transduction of piperine from black pepper (Piper nigrum L.): A comprehensive review.

Piperine, derived from black pepper (Piper nigrum L.), is responsible for the pungent sensation. The diverse bioactivities of piperine underscores its promising potential as a functional food ingredient. This review presents a comprehensive overview of the research progress in extraction, synthesis, pungency transduction mechanism and bioactivities of piperine. Piperine can be extracted through various methods, such as traditional, modern, and innovative extraction techniques. Its synthesis mainly included both chemical and biosynthetic approaches. It exhibits a diverse range of bioactivities, including anticancer, anticonvulsant, antidepressant, anti-inflammatory, antioxidant, immunomodulatory, anti-obesity, neuroprotective, antidiabetic, hepatoprotective, and cardiovascular protective activities. Piperine can bind to TRPV1 receptor to elicit pungent sensation. Overall, the present review can provide a theoretical reference for advancing the potential application of piperine in the field of food science.

Piperine-coated zinc oxide nanoparticles target biofilms and induce oral cancer apoptosis via BCl-2/BAX/P53 pathway.

BACKGROUND: Dental pathogens play a crucial role in oral health issues, including tooth decay, gum disease, and oral infections, and recent research suggests a link between these pathogens and oral cancer initiation and progression. Innovative therapeutic approaches are needed due to antibiotic resistance concerns and treatment limitations. METHODS: We synthesized and analyzed piperine-coated zinc oxide nanoparticles (ZnO-PIP NPs) using UV spectroscopy, SEM, XRD, FTIR, and EDAX. Antioxidant and antimicrobial effectiveness were evaluated through DPPH, ABTS, and MIC assays, while the anticancer properties were assessed on KB oral squamous carcinoma cells. RESULTS: ZnO-PIP NPs exhibited significant antioxidant activity and a MIC of 50 µg/mL against dental pathogens, indicating strong antimicrobial properties. Interaction analysis revealed high binding affinity with dental pathogens. ZnO-PIP NPs showed dose-dependent anticancer activity on KB cells, upregulating apoptotic genes BCL2, BAX, and P53. CONCLUSIONS: This approach offers a multifaceted solution to combatting both oral infections and cancer, showcasing their potential for significant advancement in oral healthcare. It is essential to acknowledge potential limitations and challenges associated with the use of ZnO NPs in clinical applications. These may include concerns regarding nanoparticle toxicity, biocompatibility, and long-term safety. Further research and rigorous testing are warranted to address these issues and ensure the safe and effective translation of ZnO-PIP NPs into clinical practice.

Molecular Aspects of Piperine in Signaling Pathways Associated with Inflammation in Head and Neck Cancer.

Piperine, an active plant alkaloid from black pepper (Piper nigrum), has several pharmacological effects, namely antioxidant, anti-inflammatory and immunomodulatory effects, which involve inhibiting molecular events associated with various stages of cancer development. The aim of this study was to investigate the molecular mechanisms of action of piperine in relation to its potential anticancer effect on head and neck cancer cells. Parameters related to neoplastic potential and cytokine, protein and gene expression were investigated in head and neck cancer cell lines (HEp-2 and SCC-25) treated with piperine. The results of the tests indicated that piperine modified morphology and inhibited viability and the formation of cell colonies. Piperine promoted genotoxicity by triggering apoptosis and cell cycle arrest in the G2/M and S phases. A decrease in cell migration was also observed, and there was decreased expression of MMP2/9 genes. Piperine also reduced the expression of inflammatory molecules (PTGS2 and PTGER4), regulated the secretion of cytokines (IFN-γ and IL-8) and modulated the expression of ERK and p38. These results suggest that piperine exerts anticancer effects on tumor cells by regulating signaling pathways associated with head and neck cancer.

Discovery of piperine derivatives as inhibitors of human dihydroorotate dehydrogenase to induce ferroptosis in cancer cells.

Inhibition of human dihydroorotate dehydrogenase (hDHODH) represents a promising strategy for suppressing the proliferation of cancer cells. To identify novel and potent hDHODH inhibitors, a total of 28 piperine derivatives were designed and synthesized. Their cytotoxicities against three human cancer cell lines (NCI-H226, HCT-116, and MDA-MB-231) and hDHODH inhibitory activities were also evaluated. Among them, compound H19, exhibited the strongest inhibitory activities (NCI-H226 IC50 = 0.95 µM, hDHODH IC50 = 0.21 µM). Further pharmacological investigations revealed that H19 exerted anticancer effects by inducing ferroptosis in NCI-H226 cells, with its cytotoxicity being reversed by ferroptosis inhibitors. This was supported by the intracellular growth or decline of ferroptosis markers, including lipid peroxidation, Fe2+, GSH, and 4-HNE. Overall, H19 emerges as a promising hDHODH inhibitor with potential anticancer properties warranting development.

In vitro modulation the Notch pathway by piperine: A therapeutic strategy for docetaxel-resistant and non-resistant prostate cancer.

Docetaxel (DTX) resistance poses a significant challenge in the treatment of prostate cancer (PCa), often leading to chemotherapy failure. This study investigates the ability of piperine, a compound derived from black pepper, to enhance the sensitivity of PCa cells to DTX and elucidates its underlying mechanism. We established a DTX-resistant PCa cell line, DU145/DTX, to conduct our experiments. Through a series of assays, including MTT for cell viability, flow cytometry for apoptosis, Transwell for cell migration and invasion, and western blot for protein expression analysis, we assessed the effects of piperine on these cellular functions and on the Notch signaling pathway components. Our results demonstrated that we successfully established the DTX-resistant PCa cell line DU145/DTX. Piperine effectively decreased the viability of both DU145 and its DTX-resistant counterpart, DU145/DTX, in a concentration and time-dependent manner when used alone and in combination with DTX. Notably, piperine also induced apoptosis and reduced the migration and invasion capabilities of these cells. At the molecular level, piperine down-regulated the Notch pathway by inhibiting Notch1 and Jagged1 signaling, as well as reducing the expression of downstream effectors Hey1 and hes family bHLH transcription factor 1. The study concludes that piperine's ability to modulate the Notch signaling pathway and induce apoptosis highlights its potential as a complementary treatment for DTX-resistant PCa, paving the way for the use of traditional Chinese medicinal compounds in modern oncology treatment strategies.

Piperine enhances contractile force in slow- and fast-twitch muscle.

Piperine has been shown to bind to myosin and shift the distribution of conformational states of myosin molecules from the super-relaxed state to the disordered relaxed state. However, little is known about the implications for muscle force production and potential underlying mechanisms. Muscle contractility experiments were performed using isolated muscles and single fibres from rats and mice. The dose-response effect of piperine on muscle force was assessed at several stimulation frequencies. The potentiation of muscle force was also tested in muscles fatigued by eccentric contractions. Potential mechanisms of force potentiation were assessed by measuring Ca2+ levels during stimulation in enzymatically dissociated muscle fibres, while myofibrillar Ca2+ sensitivity was assessed in chemically skinned muscle fibres. Piperine caused a dose-dependent increase in low-frequency force with no effect on high-frequency force in both slow- and fast-twitch muscle, with similar relative increases in twitch force, rate of force development and relaxation rate. The potentiating effect of piperine on low-frequency force was reversible, and piperine partially recovered low-frequency force in fatigued muscle. Piperine had no effect on myoplasmic free [Ca2+] levels in mouse muscle fibres, whereas piperine substantially augmented the force response to submaximal levels of [Ca2+] in rat MyHCII fibres and MyHCI fibres along with a minor increase in maximum Ca2+-activated force. Piperine enhances low-frequency force production in both fast- and slow-twitch muscle. The effects are reversible and can counteract muscle fatigue. The primary underlying mechanism appears to be an increase in Ca2+ sensitivity. KEY POINTS: Piperine is a plant alkaloid derived from black pepper. It is known to bind to skeletal muscle myosin and enhance resting ATP turnover but its effects on contractility are not well known. We showed for the first time a piperine-induced force potentiation that was pronounced during low-frequency electrical stimulation of isolated muscles. The effect of piperine was observed in both slow and fast muscle types, was reversible, and could counteract the force decrements observed after fatiguing muscle contractions. Piperine treatment caused an increase in myofibrillar Ca2+ sensitivity in chemically skinned muscle fibres, while we observed no effect on intracellular Ca2+ concentrations during electrical stimulation in enzymatically dissociated muscle fibres.

Piperine Enhances Antimalarial Activity of Methyl Gallate and Palmatine Combination.

PURPOSE: Artemisinin combination therapies, the first-line antimalarials in Nigeria, have reportedly suffered multiple failures in malaria treatment, hence the search for novel combination of other compounds. Methyl gallate and palmatine have been reported to exhibit antiplasmodial activities but the antimalarial activity of their combination has not been evaluated. Therefore, the evaluation of the combination of methyl gallate and palmatine for antimalarial activity in vitro and in vivo in the presence of piperine was carried out. MATERIALS AND METHODS: The inhibitory potential of methyl gallate and palmatine combination on ß-hematin (hemozoin) formation was studied in vitro. Also, the antimalarial activity of methyl gallate and palmatine combination with/without a bioenhancer (piperine) was evaluated in Plasmodium berghei NK65-infected mice. RESULTS: Methyl gallate and palmatine in the ratio 3:2 acted synergistically in vitro and had the highest inhibitory effect (IC50 = 0.73 µg/mL) on ß-hematin (hemozoin) formation. The 3:2 combination of methyl gallate and palmatine exhibited no antimalarial activity in vivo in the absence of piperine but caused reduction in parasitemia that exceeded 40% in the presence of piperine at the dose of 25 mg/kg body weight on days 6 and 8 post-inoculation in mice. CONCLUSION: The 3:2 combination of methyl gallate and palmatine in the presence of piperine exhibited antimalarial activity in vivo, possibly by synergistic inhibition of hemozoin formation which may cause accumulation of haem within the food vacuole of Plasmodium spp. and its death.

Comparative Pharmacokinetics of Curcuminoids from Water-Dispersible Turmeric Extract Against a Curcuminoids-Piperine Combination: An Open-Label, Randomized, Balanced, 2-Treatment, 2-Sequence, 2-Period Crossover Study.

Objective: Curcuminoids, the major component of which is curcumin, are natural polyphenolic compounds from the rhizome of Curcuma longa Linn. and possess extensive biopharmacological properties that are limited in humans due to poor bioavailability. Currently, most commercial bioavailable turmeric extracts use synthetic excipients or the addition of piperine to enhance bioavailability, and are needed in multiple daily doses to achieve clinical efficacy. This study was conducted to compare the bioavailability of a natural, water-dispersible turmeric extract containing 60% natural curcuminoids, the test product, WDTE60N (1 × 250 mg per day), with the reference product, turmeric extract capsules (500 mg curcuminoids and 5 mg piperine, CPC; 3 × 500 mg per day). Methods: Sixteen healthy adult male subjects fasted overnight for 10 hours and then were dosed with either one capsule of the test product WDTE60N or three capsules of reference product CPC orally (One capsule administered at every 6 hours interval i.e. at 0.00 hrs, 6.00 hrs and at 12.00 hrs) in each study period. Blood sampling before and after dosing was carried out at defined time points at -12.00, -02.00, 00.00 (within 10 minutes prior to dosing) hours in morning before dosing and post-dose (First dose) at 00.50, 01.00, 02.00, 03.00, 04.00, 05.00, 06.50, 07.00, 08.00, 09.00, 10.00, 11.00, 12.50, 13.00, 14.00, 16.00, 18.00, 20.00 and 24.00 hours in each period. Plasma concentration of curcuminoids was determined using a validated liquid chromatography with tandem mass spectrometry bioanalytical method. Results: The Cmax (GLSM) for the test product WDTE60N was observed to be 74.56 ng/mL; and same for the reference CPC was 22.75 ng/mL. AUC0-t (GLSM) for test WDTE60N was 419.00 h∙ng/mL; and for reference CPC it was 359.86 h∙ng/mL for total curcuminoids. Conclusion: The test formulation WDTE60N showed improved relative absorption and equivalent exposure at a 10-fold-lower dose of actives than the reference formulation CPC.

The endocannabinoid anandamide activates pro-resolving pathways in human primary macrophages by engaging both CB2 and GPR18 receptors.

Resolution of inflammation is the cellular and molecular process that protects from widespread and uncontrolled inflammation and restores tissue function in the aftermath of acute immune events. This process is orchestrated by specialized pro-resolving mediators (SPM), a class of bioactive lipids able to reduce immune activation and promote removal of tissue debris and apoptotic cells by macrophages. Although SPMs are the lipid class that has been best studied for its role in facilitating the resolution of self-limited inflammation, a number of other lipid signals, including endocannabinoids, also exert protective immunomodulatory effects on immune cells, including macrophages. These observations suggest that endocannabinoids may also display pro-resolving actions. Interestingly, the endocannabinoid anandamide (AEA) is not only known to bind canonical type 1 and type 2 cannabinoid receptors (CB1 and CB2) but also to engage SPM-binding receptors such as GPR18. This suggests that AEA may also contribute to the governing of resolution processes. In order to interrogate this hypothesis, we investigated the ability of AEA to induce pro-resolving responses by classically-activated primary human monocyte-derived macrophages (MoDM). We found that AEA, at nanomolar concentration, enhances efferocytosis in MoDMs in a CB2- and GPR18-dependent manner. Using lipid mediator profiling, we also observed that AEA modulates SPM profiles in these cells, including levels of resolvin (Rv)D1, RvD6, maresin (MaR)2, and RvE1 in a CB2-dependent manner. AEA treatment also modulated the gene expression of SPM enzymes involved in both the formation and further metabolism of SPM such as 5-lipoxygenase and 15-Prostaglandin dehydrogenase. Our findings show, for the first time, a direct effect of AEA on the regulation of pro-resolving pathways in human macrophages. They also provide new insights into the complex interactions between different lipid pathways in activation of pro-resolving responses contributing to the reestablishment of homeostasis in the aftermath of acute inflammation.

Curcumin, Piperine and Taurine Combination Enhances the Efficacy of Transarterial Chemoembolization Therapy in patients with Intermediate Stage Hepatocellular Carcinoma: A Pilot Study.

INTRODUCTION: Diagnosis of the majority of hepatocellular carcinoma (HCC) patients occurs at intermediate to advanced stages, with a few curative therapeutic options being available. It is therefore strongly urgent to discover additional adjuvant therapy for this lethal malignancy. This study aimed to assess the effectiveness of curcumin (C), piperine (P) and taurine (T) combination as adjuvant agents on serum levels of IFN-γ, immunophenotypic and molecular characterization of mononuclear leukocytes (MNLs) in HCC patients treated with Transarterial chemoembolization (TACE). PATIENTS AND METHODS: Serum and MNLs were collected from 20 TACE-treated HCC patients before (baseline-control samples) and after treatment with 5 g curcumin capsules , 10 mg piperine and 0.5 mg taurine taken daily for three consecutive months. Immunophenotypic and molecular characterization of MNLs were determined by flow cytometry and quantitative real time PCR, respectively. In addition, serum IFN-γ level was quantified by ELISA. RESULTS: After receiving treatment with CPT combination, there was a highly significant increase in IFN- γ levels in the sera of patients when compared to basal line control samples. Additionally, the group receiving combined therapy demonstrated a downregulation in the expression levels of PD-1, in MNLs as compared to controls. MNLs' immunophenotyping revealed a significant decline in CD4+CD25+cells (regulatory T lymphocytes). Furthermore, clinicopathological characteristics revealed a highly significant impact of CPT combination on aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and alpha feto protein (AFP) levels. CONCLUSION: This study introduces a promising adjuvant CPT combined treatment as natural agents to enhance the management of HCC patients who are candidates to TACE treatment.

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.

Combination of 308-nm excimer laser and piperine promotes melanocyte proliferation, migration, and melanin content production via the miR-328/SFRP1 axis.

OBJECTIVE: Both piperine and a 308-nm excimer laser have significant curative effects on vitiligo. This study mainly explored the molecular mechanism of a 308-nm excimer combined with piperine in regulating melanocyte proliferation. METHODS: Epidermal melanocytes were cultured in piperine solution, and the cells were irradiated by an XTRAC excimer laser treatment system at 308-nm output monochromatic light. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were for detecting the expression levels of genes or proteins. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and Transwell method was for assessing cell viability and migration capacity. The content of melanin was also detected. RESULTS: The combination of the 308-nm excimer laser and piperine enhanced the cell proliferation, migration, and melanin production of melanocytes and upregulated the level of miR-328, and restraint of miR-328 reversed the influence of the 308-nm excimer laser and piperine. Secreted frizzled-related protein 1 (SFRP1) is a direct target gene of miR-328, and miR-328 can inhibit the expression of SFRP1 and elevate the protein level of the Wnt/ß-catenin signaling pathway. CONCLUSION: The 308-nm excimer laser combined with piperine may be more efficient than piperine alone in the remedy of vitiligo, and the miR-328/SFRP1 and Wnt/ß-catenin pathways are participated in the proliferation, migration, and melanin synthesis of melanocytes.

Formulation and evaluation of dissolving microneedle for transdermal delivery of piperine: the effect of polymers concentration.

This research aims to develop the formulation of Dissolving Microneedle Piperine (DMNs PIP) and evaluate the effect of polymer concentration on characterisation and permeation testing results in ex vivo. DMNs PIP were prepared from varying concentrations of piperine (PIP) (10, 15, and 20% w/w) and polymers of polyvinyl alcohol (PVA): Polyvinyl pyrrolidone (30:60 and 60:25), respectively. Then the morphological evaluation of the formula was carried out, followed by mechanical strength testing. Furthermore, the density, LOD, and weight percentage of piperine in the dried microneedle were calculated and the determination of volume, needle weight and piperine weight and analysed. Ex vivo testing, X-Ray Diffraction, FTIR and hemolysis tests were carried out. PIP with PVA and PVP (F1) polymers produced DMN with mechanical strength (8.35 ± 0.11%) and good penetration ability. In vitro tests showed that the F1 polymer mixture gave good penetration (95.02 ± 1.42 µg/cm2), significantly higher than the F2, F3, F4, and F5 polymer mixtures. The DMNs PIP characterisation results through XRD analysis showed a distinctive peak in the 20-30 region, indicating the presence of crystals. The FTIR study showed that the characteristics of piperine found in DMNs PIP indicated that piperine did not undergo interactions with polymers. The results of the ex vivo study through DMNs PIP hemolytic testing showed no hemolysis occurred, with the hemolysis index below the 5% threshold reported in the literature. These findings indicate that DMNs PIP is non-toxic and safe to use as alternative for treating inflammation.

Piperine improves the health span of Drosophila melanogaster with age- and sex-specific effect.

Piperine, a dietary phytochemical isolated from the Piper species, has been used as a natural medicine for pain, flu, and fever in ancient China and India. Although the health benefits of piperine have been widely studied, research on its effect on aging is limited. This study aimed to determine whether piperine has the potential to mitigate aging-related changes in the fruit fly (Drosophila melanogaster), which is an excellent model organism for studies on aging. The experiments were conducted using the newly eclosed or 30-day-old D. melanogaster wild-type strain Cantonized-white. Piperine was dissolved in 99% ethanol and added to the sucrose-yeast medium at a final concentration of 10, 35, 70, or 100 µM. The study examined the effects of piperine supplementation on the lifespan of D. melanogaster and other physiological functions, such as fecundity, feeding, lipid content, and resistance to environmental stress. Log-rank tests, Shapiro-Wilk test, F-test, t-test, or Wilcoxon rank sum test were used to analyze the data. Piperine failed to change the lifespan and body weight, but increased the fecundity and decreased the feeding rate in one-week-old flies. However, when piperine was fed to 30-day-old flies, it increased the lifespan of male flies and the fecundity and feeding rate of female flies. These results indicate that piperine can improve the health of aged flies. The findings suggest that piperine has age-dependent and sex-specific anti-aging effects in fruit flies.