Inhibition of lipopolysaccharide-induced inflammatory responses by piperine

Effects of dietary piperine supplementation on innate immunity, growth performance, feed utilization and intestinal morphology of olive flounder (Paralichthys olivaceus)

Piperine, the main bioactive component of black pepper (Piper nigrum) or long pepper (Piper longum), has anti-inflammatory, antifungal, and antibacterial properties. This study was carried out to evaluate the supplemental effects of piperine in olive flounder (Paralichthys olivaceus) diets. Six isonitrogenous and isolipidic diets were formulated to contain different levels of piperine at 0.00, 0.25, 0.50, 0.75, 1.00, and 2.00 g/kg (Con, P25, P50, P75, P100, and P200, respectively). Diets were randomly allocated to triplicate groups of fish (initial weight 27.6 ± 0.4 g, 30 fish/tank) and fed three times daily for 8 weeks. Results showed that dietary piperine significantly improved fish growth and feed utilization efficiency. The highest growth, including the highest Igf-1 mRNA expression, was observed in the P50 group, while P50 and P75 groups showed the highest protein efficiency ratio. Compared to the Con group piperine supplemented groups had significantly higher lysozyme activity, immunoglobulin level, and phagocytosis activities. Plasma cholesterol was significantly lower in fish fed P200 diet. Dry matter and protein digestibility were higher in P25, P50, and P75 groups than in Con group. Dietary piperine increased the intestinal villi length and goblet cell counts. In the challenge test against Edwardsiella tarda, all the groups supplemented with piperine showed higher cumulative survival compared to Con group. Therefore, these findings indicate that dietary piperine supplementation can improve growth performance, innate immunity, disease resistance, diet digestibility, and intestinal morphology of olive flounder. The optimum dietary piperine level seems to be approximately 0.5 g/kg for the fish.

A brief overview of SARS-CoV-2 infection and its management strategies: a recent update

The COVID-19 pandemic has become a global health crisis, inflicting substantial morbidity and mortality worldwide. A diverse range of symptoms, including fever, cough, dyspnea, and fatigue, characterizes COVID-19. A cytokine surge can exacerbate the disease's severity. This phenomenon involves an increased immune response, marked by the excessive release of inflammatory cytokines like IL-6, IL-8, TNF-α, and IFNγ, leading to tissue damage and organ dysfunction. Efforts to reduce the cytokine surge and its associated complications have garnered significant attention. Standardized management protocols have incorporated treatment strategies, with corticosteroids, chloroquine, and intravenous immunoglobulin taking the forefront. The recent therapeutic intervention has also assisted in novel strategies like repurposing existing medications and the utilization of in vitro drug screening methods to choose effective molecules against viral infections. Beyond acute management, the significance of comprehensive post-COVID-19 management strategies, like remedial measures including nutritional guidance, multidisciplinary care, and follow-up, has become increasingly evident. As the understanding of COVID-19 pathogenesis deepens, it is becoming increasingly evident that a tailored approach to therapy is imperative. This review focuses on effective treatment measures aimed at mitigating COVID-19 severity and highlights the significance of comprehensive COVID-19 management strategies that show promise in the battle against COVID-19.

Maternal immune activation as an epidemiological risk factor for neurodevelopmental disorders: Considerations of timing, severity, individual differences, and sex in human and rodent studies

Epidemiological evidence suggests that one's risk of being diagnosed with a neurodevelopmental disorder (NDD)-such as autism, ADHD, or schizophrenia-increases significantly if their mother had a viral or bacterial infection during the first or second trimester of pregnancy. Despite this well-known data, little is known about how developing neural systems are perturbed by events such as early-life immune activation. One theory is that the maternal immune response disrupts neural processes important for typical fetal and postnatal development, which can subsequently result in specific and overlapping behavioral phenotypes in offspring, characteristic of NDDs. As such, rodent models of maternal immune activation (MIA) have been useful in elucidating neural mechanisms that may become dysregulated by MIA. This review will start with an up-to-date and in-depth, critical summary of epidemiological data in humans, examining the association between different types of MIA and NDD outcomes in offspring. Thereafter, we will summarize common rodent models of MIA and discuss their relevance to the human epidemiological data. Finally, we will highlight other factors that may interact with or impact MIA and its associated risk for NDDs, and emphasize the importance for researchers to consider these when designing future human and rodent studies. These points to consider include: the sex of the offspring, the developmental timing of the immune challenge, and other factors that may contribute to individual variability in neural and behavioral responses to MIA, such as genetics, parental age, the gut microbiome, prenatal stress, and placental buffering.

Plants' bioactive secondary metabolites in the management of sepsis: Recent findings on their mechanism of action

Sepsis is a severe inflammatory response to systemic infection and is a threatening cause of death in intensive care units. In recent years, a number of studies have been conducted on the protective effect of natural products against sepsis-induced organ injury. However, a comprehensive review of these studies indicating the mechanisms of action of the bioactive compounds is still lacking. In this context, this review aimed to provide an updated analysis of the mechanism of action of plants' secondary metabolites in the management of sepsis. Scopus, Science Direct, Google Scholar, and PubMed were searched from inception to July 2022. A variety of secondary metabolites were found to be effective in sepsis management including allicin, aloin, cepharanthine, chrysin, curcumin, cyanidin, gallic acid, gingerol, ginsenoside, glycyrrhizin, hesperidin, kaempferol, narciclasine, naringenin, naringin, piperine, quercetin, resveratrol, rosmarinic acid, shogaol, silymarin, sulforaphane, thymoquinone, umbelliferone, and zingerone. The protective effects exerted by these compounds can be ascribed to their antioxidant properties as well as induction of endogenous antioxidant mechanisms, and also via the downregulation of inflammatory response and reduction of biochemical and inflammatory markers of sepsis. These findings suggest that these secondary metabolites could be of potential therapeutic value in the management of sepsis, but human studies must be performed to provide strength to their potential clinical relevance in sepsis-related morbidity and mortality reduction.

Protective Effects of Piperine on Ethanol-Induced Gastric Mucosa Injury by Oxidative Stress Inhibition

Piper nigrum Linnaeus is often used as a treatment for chills, stomach diseases, and other ailments. Piperine has many biological functions; however, its mechanism for preventing gastric mucosal damage is still unclear. The objective of this study was to investigate the preventive effects of piperine on ethanol-induced gastric mucosal injury by using GES-1 cells and rats. SOD, CAT, GSH-Px and MDA were effectively regulated in GES-1 cells pre-treated with piperine. Piperine significantly increased SOD, CAT and GSH-Px activities, but decreased the ulcer area, MDA, ROS and MPO levels in the gastric tissues of rats. RT-PCR analysis showed that piperine downregulated the mRNA expression levels of keap1, JNK, ERK and p38, and upregulated the mRNA transcription levels of Nrf2 and HO-1. Western blotting results indicated that piperine could activate the protein expression levels of Nrf2 and HO-1 and inhibit the protein expression levels of keap1, p-JNK, p-ERK and p-p38. In conclusion, piperine suppressed ethanol-induced gastric ulcers in vitro and in vivo via oxidation inhibition and improving gastric-protecting activity by regulating the Nrf2/HO-1 and MAPK signalling pathways.

Piperine Derived from Piper nigrum L. Inhibits LPS-Induced Inflammatory through the MAPK and NF-κB Signalling Pathways in RAW264.7 Cells

Piperine, an important natural product, has a good anti-inflammatory effect. However, few researchers have studied its mechanism in these pathways. The objective of this research was to evaluate the molecular mechanism underlying the anti-inflammatory responses of piperine in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The purification and characterization of piperine from Piper nigrum L. were determined by HPLC, UPLC-Q-TOF-MS and ¹H NMR. Then, the anti-inflammatory activity was evaluated by a reagent test kit, ELISA kits, RT-PCR and Western blot experiments. The results suggested that piperine (90.65 ± 0.46% purity) at a concentration of 10–20 mg/L attenuated the production of NO and ROS, downregulated the protein and mRNA expression levels of TNF-α, IL-1β and IL-6, and upregulated the protein and mRNA transcription levels of IL-10. Meanwhile, the Western blot results indicated that piperine could inhibit the phosphorylation levels of the ERK, JNK, p38 and p65 proteins. Our findings suggest that piperine is a potential anti-inflammatory substance, whose molecular mechanism may be to regulate the key factors of the NF-κB and MAPK signalling pathways.

Therapeutic spectrum of piperine for clinical practice: a scoping review

Translation of traditional knowledge of herbs into a viable product for clinical use is still an uphill task. Piperine, a pungent alkaloid molecule derived from Piper nigrum and Piper longum possesses diverse pharmacological effects. Traditionally, pepper is used for arthritis, bronchitis, gastritis, diarrhea, snake bite, menstrual pain, fever, and bacterial infections, etc. The anti-inflammatory, antioxidant and immunomodulatory actions of piperine are the possible mechanisms behind its therapeutic potential. Various in-silico and experimental studies have shown piperine as a possible promising molecule in coronavirus disease (COVID-19), ebola, and dengue due to its immunomodulatory and antiviral activities. The other important clinical applications of piperine are due to its bio enhancing effect on drugs, by modulating, absorption in the gastrointestinal tract, altering activities of transporters like p-glycoprotein substrates, and modulating drug metabolism by altering the expression of cytochrome P450 or UDP-glucuronosyltransferase enzymes. Piperine attracted clinicians in treating patients with arthritis, metabolic syndrome, diabetes, skin infections, gastric and liver disorders. This review focused on systematic, evidence-based insight into the use of piperine in clinical settings and mechanistic details behind its therapeutic actions. Also, highlights a number of clinical trials of piperine at various stages exploring its clinical application in cancer, neurological, respiratory, and viral disease, etc.

COVID-19: General Strategies for Herbal Therapies

The coronavirus disease-2019 (COVID-19) pandemic started in early 2020 with the outbreak of a highly pathogenic human coronavirus. The world is facing a challenge and there is a pressing need for efficient drugs. Plants and natural compounds are a proven rich resource for new drug discovery. Considering the potential of natural products to manage the pandemic, this article was designed to provide an inclusive map of the stages and pathogenetic mechanisms for effective natural products on COVID-19. New drug discovery for the COVID-19 pandemic can encompass both prevention and disease management strategies. Preventive mechanisms that may be considered include boosting the immune response and hand hygiene in the preexposure phase; and blocking of virus binding and entry in the postexposure phase. Potential therapeutic target mechanisms include virus-directed therapies and host-directed therapies. Several medicinal plants and natural products, such as Withania somnifera (L.) Dunal and propolis for prevention; Tanacetum parthenium (L.) for treatment; and Ammoides verticillata (Desf.) Briq and Nigella sativa L. for both prevention and treatment have been found effective and are good targets for future research. The examples of phytochemical compounds that may be effective include aloin and terpenes as anti-septics; isothymol, dithymoquinone, and glycyrrhizin as inhibitors of virus binding and entry; glycyrrhizin, and berberine as replication suppressants; ginsenoside Rg1 and parthenolide as immunomodulators; and eriocitrin, rhoifolin, hesperidin, naringin, rutin, and veronicastroside as anti-complements. Recognizing different mechanisms of fighting against this virus can lead to a more systematic approach in finding natural products and medicinal plants for COVID-19 prevention and treatment.

Synergistic effect of ursolic acid and piperine in CCl4 induced hepatotoxicity

BACKGROUND

Ursolic acid (UA) is a potent plant-based hepatoprotective agent having poor bioavailability, which hampers its therapeutic efficacy. The present study tries to overcome this limitation by combining it with piperine (PIP), a proven bioenhancer and hepatoprotective agent.

METHODS

The type of interaction (synergism, addition, or antagonism) resulting between UA and PIP was analyzed and quantified by isobologram and combination index analysis. The hepatoprotective activity of UA and PIP was evaluated by measuring the level of hepatic marker enzymes. Pharmacokinetic analysis was carried out to ascertain the improvement of bioavailability.

RESULTS

The combinations significantly decrease the enzyme levels, which indicate better hepatoprotective activity compared to single drugs. The relative oral bioavailability of UA was increased about tenfold (from AUC0-t =12.78 ± 2.59 µg/h/ml to 125.15 ± 1.84 µg/h/ml) along with the improvement of plasma concentration and elimination half-life.

CONCLUSIONS

The findings indicated that the combination of PIP and UA is an effective strategy in enhancing the bioavailability and hepatoprotective potential of UA.KEY MESSAGESUrsolic acid in a combination with piperine provides a synergistic hepatoprotective effect in carbon tetrachloride induced liver damage in rats.Piperine improves the pharmacokinetic properties of ursolic acid when given in combination.Piperine improves the relative oral bioavailability of ursolic acid by tenfold when combined together.

Anethum sowa Roxb. ex fleming: A review on traditional uses, phytochemistry, pharmacological and toxicological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Anethum sowa Roxb. ex Fleming (Syn. Peucedanum sowa Roxb. ex Fleming, Family: Apiaceae) is a pharmacologically important as aromatic and medicinal plant. Various parts of this plant are used in traditional medicine systems for carminative, uterine and colic pain, digestion disorder, flatulence in babies, appetite-stimulating agent and used to treat mild flue and cough. The essential oil is used for aromatherapy. It is also used as a spice for food flavouring and culinary preparations in many Asian and European countries.

AIM OF THE REVIEW

This review aims to provide a comprehensive and critical assessment from the reported traditional and pharmaceutical uses and pharmacological activities of the extracts, essential oil and phytoconstituents with emphasis on its therapeutic potential as well as toxicological evaluation of A. sowa.

MATERIALS AND METHODS

Online search engines such as SciFinder®, GoogleScholar®, ResearchGate®, Web of Science®, Scopus®, PubMed and additional data from books, proceedings and local prints were searched using relevant keywords and terminologies related to A. sowa for critical analyses.

RESULTS

The literature studies demonstrated that A. sowa possesses several ethnopharmacological activities, including pharmaceutical prescriptions, traditional applications, and spice in food preparations. The phytochemical investigation conducted on crude extracts has been characterized and identified various classes of compounds, including coumarins, anthraquinone, terpenoids, alkaloid, benzodioxoles, phenolics, polyphenols, phenolic and polyphenols, fatty acids, phthalides and carotenoids. The extracts and compounds from the different parts of A. sowa showed diverse in vitro and in vivo biological activities including antioxidant, antiviral, antibacterial, analgesic and anti-inflammatory, Alzheimer associating neuromodulatory, cytotoxic, anticancer, antidiabetes, insecticidal and larvicidal.

CONCLUSION

A. sowa is a valuable medicinal plant which is especially used in food flavouring and culinary preparations. This review summarized the pertinent information on A. sowa and its traditional and culinary uses, as well as potential pharmacological properties of essential oils, extracts and isolated compounds. The traditional uses of A. sowa are supported by in vitro/vivo pharmacological studies; however, further investigation on A. sowa should be focused on isolation and identification of more active compounds and establish the links between the traditional uses and reported pharmacological activities with active compounds, as well as structure-activity relationship and in vivo mechanistic studies before integrated into the medicine. The toxicological report confirmed its safety. Nonetheless, pharmacokinetic evaluation tests to validate its bioavailability should be encouraged.

Evaluation of piperine against cancer stem cells (CSCs) of hepatocellular carcinoma: Insights into epithelial-mesenchymal transition (EMT)

Cancer stem cells (CSCs) are involved in recurrent hepatocellular carcinoma (HCC), yet there is a lack of effective treatment that targets these CSCs. CD44+ and CD133+ CSCs are markedly expressed in HepG2 cells and were isolated and characterized using fluorescence-activated cell sorting (FACS) analysis. Since piperine is known as an effective molecule against metastasis, we thought to investigate the effect of piperine against CD44+/CD133+ CSCs. Herein, piperine was found to be active against these CSCs. Also, it was found appropriate to respite at the 'subG₀/G₁ and G₀/G₁' phase of the cell cycle analysis, respectively. TGF-β activated epithelial-mesenchymal transition (EMT) has been involved in the invasion and metastasis of HepG2 cells in hepatocellular carcinoma. Therefore, we next investigated the effect of piperine on different biomarkers that remarkably takes part in the process of EMT using flow cytometric analysis. Piperine was found able to repress the epithelial marker (E-cadherin) but was unable to restore the level of Vimentin (mesenchymal marker) and SNAIL (EMT-inducing transcription factor). Therefore, the findings of this study revealed that piperine could be an effective treatment strategy for recurrent hepatocarcinogenesis.

Efficacy and Safety of Sahastara Remedy Extract Capsule in Primary Knee Osteoarthritis: A Randomized Double-Blinded Active-Controlled Trial

Sahastara (SHT) remedy is a Thai traditional medicine described in the Thai National List of Essential Medicine (NLEM) for the relief of muscle pain. The purpose of this study was to investigate the efficacy and safety of SHT remedy extract capsule for treating primary OA. A phase 2, double-blind, randomized, and controlled trial study was used to determine the clinical efficacy and safety of SHT in comparison with diclofenac for the treatment of knee OA. The outcome of reduce pain was measured from VAS, 100 meter time walk, and the WOMAC score of day 14 and day 28 which should reduce significantly when compared with day 0 and should be equal with or better than diclofenac. Blood pressure and blood chemistry values at day 14 and day 28 did not change when compared with day 0. The results found that SHT remedy ethanolic extract capsule can reduce all OA knee scores at day 14 and day 28 significantly when compared with day 0 and also no significant difference with diclofenac (P > 0.05). The SHT also showed safety values on blood pressure and blood chemistry. The SHT was observed that it had no serious side effect. The results of this study are the first report of using the SHT ethanolic extract capsule in the treatment of primary osteoarthritis of the knee. It can be recommended as an anti-inflammatory herbal drug for reducing pain in knee osteoarthritis patients.

Piperine from Black Pepper Decreased the Expression of Intercellular Adhesion Molecule-1 in Macrophages

BACKGROUND

Macrophages are the main players involved in inflammation. Intercellular adhesion molecule-1 (ICAM-1) facilitates macrophage polarization prior to extravasation into inflamed tissue. Piperine, a natural product derived from black pepper, possesses useful biological and pharmacological activities. In the current study, the possible anti-inflammatory effect of piperine on the expression of ICAM-1 on J774.1 murine macrophage cell line was investigated.

METHODS

Lipopolysaccharide (LPS)-stimulated J774.1 cells were cultured in the presence of different concentrations of piperine to examine the changes in ICAM-1 expression by real-time PCR and flow cytometry.

RESULTS

We found that piperine decreased ICAM-1 gene expression level from 2.4 ± 0.25 RFC (relative fold change) in LPS-only treated cells to 0.85 ± 0.525 RFC at 1µg/ml (p<0.05), 0.43 ± 0.27 RFC at 10µg/ml (p<0.01), and 0.26 ± 0.25 RFC at 20µg/ml (p<0.01). In flow cytometry, piperine at all concentrations significantly decreased ICAM-1 surface expressions (P<0.05). The geometric mean fluorescence intensity (g-MFI) in LPS-only treated cells (792 ± 57.3) decreased to 482±70 g-MFI at 20 μg/ml piperine.

CONCLUSION

According to the results of this study, by decreasing the expression of ICAM-1, piperine has been suggested to reduce inflammation and have the potential to provide therapeutic benefits for immune-mediated diseases.

A Review of Malaysian Herbal Plants and Their Active Constituents with Potential Therapeutic Applications in Sepsis

Sepsis refers to organ failure due to uncontrolled body immune responses towards infection. The systemic inflammatory response triggered by pathogen-associated molecular patterns (PAMPs), such as lipopolysaccharide (LPS) from Gram-negative bacteria, is accompanied by the release of various proinflammatory mediators that can lead to organ damage. The progression to septic shock is even more life-threatening due to hypotension. Thus, sepsis is a leading cause of death and morbidity globally. However, current therapies are mainly symptomatic treatment and rely on the use of antibiotics. The lack of a specific treatment demands exploration of new drugs. Malaysian herbal plants have a long history of usage for medicinal purposes. A total of 64 Malaysian plants commonly used in the herbal industry have been published in Malaysian Herbal Monograph 2015 and Globinmed website (http://www.globinmed.com/). An extensive bibliographic search in databases such as PubMed, ScienceDirect, and Scopus revealed that seven of these plants have antisepsis properties, as evidenced by the therapeutic effect of their extracts or isolated compounds against sepsis-associated inflammatory responses or conditions in in vitro or/and in vivo studies. These include Andrographis paniculata, Zingiber officinale, Curcuma longa, Piper nigrum, Syzygium aromaticum, Momordica charantia, and Centella asiatica. Among these, Z. officinale is the most widely studied plant and seems to have the highest potential for future therapeutic applications in sepsis. Although both extracts as well as active constituents from these herbal plants have demonstrated potential antisepsis activity, the activity might be primarily contributed by the active constituent(s) from each of these plants, which are andrographolide (A. paniculata), 6-gingerol and zingerone (Z. officinale), curcumin (C. longa), piperine and pellitorine (P. nigrum), biflorin (S. aromaticum), and asiaticoside, asiatic acid, and madecassoside (C. asiatica). These active constituents have shown great antisepsis effects, and further investigations into their clinical therapeutic potential may be worthwhile.

Immune-Boosting, Antioxidant and Anti-inflammatory Food Supplements Targeting Pathogenesis of COVID-19

The COVID-19 is an acute and contagious disease characterized by pneumonia and ARDS. The disease is caused by SARS-CoV-2, which belongs to the family of Coronaviridae along with MERS-CoV and SARS-CoV-1. The virus has the positive-sense RNA as its genome encoding for ~26 proteins that work together for the virus survival, replication, and spread in the host. The virus gets transmitted through the contact of aerosol droplets from infected persons. The pathogenesis of COVID-19 is highly complex and involves suppression of host antiviral and innate immune response, induction of oxidative stress followed by hyper inflammation described as the "cytokine storm," causing the acute lung injury, tissue fibrosis, and pneumonia. Currently, several vaccines and drugs are being evaluated for their efficacy, safety, and for determination of doses for COVID-19 and this requires considerable time for their validation. Therefore, exploring the repurposing of natural compounds may provide alternatives against COVID-19. Several nutraceuticals have a proven ability of immune-boosting, antiviral, antioxidant, anti-inflammatory effects. These include Zn, vitamin D, vitamin C, curcumin, cinnamaldehyde, probiotics, selenium, lactoferrin, quercetin, etc. Grouping some of these phytonutrients in the right combination in the form of a food supplement may help to boost the immune system, prevent virus spread, preclude the disease progression to severe stage, and further suppress the hyper inflammation providing both prophylactic and therapeutic support against COVID-19.

Streptozotocin-induced diabetic cardiomyopathy in rats: ameliorative effect of PIPERINE via Bcl2, Bax/Bcl2, and caspase-3 pathways

The objective of present investigation was to appraise the effects of piperine on STZ-induced diabetic cardiomyopathy in rats. Diabetes was induced in Sprague-Dawley rats with intraperitoneal STZ injection, and the rats were assigned to seven groups. Electrocardiograph, hemodynamic, various biochemical, molecular, and histological parameters were examined. Treatment with piperine significantly (p < 0.05) restored altered myocardial functions, inhibited cardiac marker, and restored electrocardiogram and hemodynamic alterations. The elevated level of cardiac oxido-nitrosative stress and decreased cardiac Na-K-ATPase concentration, after STZ administration, were significantly (p < 0.05) attenuated by piperine treatment. Piperine also considerably (p < 0.05) increased myocardial mitochondrial enzyme activity. STZ-induced alteration in heart ANP, BNP, cTn-I, Bcl2, Bax/Bcl2, and caspase3 mRNA expression was significantly (p < 0.05) restored by piperine treatment. Piperine administration reduced histopathological aberrations induced by STZ. In conclusion, the present investigation suggests that piperine ameliorates STZ-induced diabetic cardiomyopathy via modulation of caspase-3, Bcl2, Bax/Bcl2 pathways. Abbreviations: ACE: Angiotensin-Converting Enzyme; ANOVA: Analysis of Variance; ANP: Atrial Natriuretic Peptide; APAF: Apoptotic Protease-Activating Factor; ARB: Angiotensin Receptor Blockers; ATP: Adenosine Triphosphate; Bax: Bcl-2-associated X protein; Bcl2: B-cell lymphoma 2; BPM: Beats Per Minute; BNP: brain natriuretic peptide; CAD: Caspase-3-Activated DNase; cDNA: Complementary DNA; CK-MB: Creatine Kinase-MB; CPCSEA: Committee for the Purpose of Control And Supervision of Experiments on Animals; cTn-I: cardiac troponin I; DBP: Diastolic Blood Pressure; DCM: Diabetic Cardiomyopathy; DNA: Deoxyribonucleic Acid; DPX: DisterenePhthalate Xylene; ECG: Electrocardiogram; ETC: Electron Transport Chain; GOD-POD: Glucose Oxidase Peroxidase; GSH: Glutathione; IAEC: Institutional Animal Ethics Committee; IL-6: Interleukin-6; IL-1b: Interleukin-1b; LDH: Lactate Dehydrogenase; LV: Left Ventricle; LVEDP: left ventricular end-diastolic Pressure; MABP: Mean Arterial Blood Pressure; MDA: Malondialdehyde; mRNA: Messenger Ribonucleic Acid; MTT: 3- (4,5-Dimethylthiazol-2-yl)-2,5-DiphenyltetrazoliumBromide; NADH: Nicotinamide Adenine Dinucleotide Phosphate; NADPH: Nicotinamide Adenine Dinucleotide Phosphate Hydrogen; NO: nitric oxide; NP: Natriuretic Peptides; OXPHOS: Oxidative Phosphorylation; p.o.: per os; PCR: Polymerase Chain Reaction; RT-PCR: Reverse Transcriptionpolymerase Chain Reaction; PPAR: Peroxisome Proliferator-Activated Receptor Gamma; RAS: Renin-Angiotensin System; RNA: Ribonucleic Acid; ROS: Reactive Oxygen Species; SBP: Systolic Blood Pressure; SDH: Succinate Dehydrogenase; SEM: Standard Error Means; SOD: superoxide dismutase: STZ: Streptozotocin; TNF: Tumor Necrosis Factor Alpha; TnI: Troponin I.

Percutaneous Microdialysis and Pharmacokinetic Study of Tongluo-Qutong Rubber Plaster in Rats by UPLC-MS/MS

Tongluo-Qutong rubber plaster (TQRP) is a well-known traditional Chinese medicine prescription for the treatment of osteoarthritis and cervical spondylosis. Due to a lack of in vivo permeation data, the active ingredients of TQRP have not been fully elucidated, presenting a huge obstacle to quality evaluation, pharmacokinetic studies, and safety assessment of TQRP for clinical application. In this study, a selective and reproducible ultraperformance liquid chromatography tandem mass spectrometry method was developed and validated for percutaneous microdialysis and pharmacokinetic experiments. In the percutaneous microdialysis study, the mean area under the concentration–time curve (AUC0-24h) of emodin (EMO) and piperine (PIP) were 127.1 and 2603.6 h·ng/mL, respectively. In the pharmacokinetic study, ferulic acid (FA), EMO, and PIP were determined in plasma samples. The mean AUC0-32h values of FA, EMO, and PIP in plasma were 15441.5, 202.0, and 1704.5 h·ng/mL, respectively. The in vivo exposure levels of active ingredients such as FA, EMO, and PIP after dermal administration of TQRP provide insights and data to support identification of its bioactive components and further study of its mechanism of action.

A systematic review on Piper longum L.: Bridging traditional knowledge and pharmacological evidence for future translational research

ETHNOPHARMACOLOGICAL RELEVANCE

Piper longum, commonly referred as 'Pippali', has found its traditional use in India, Malaysia, Singapore and other South Asian countries as an analgesic, carminative, anti-diarrhoeic, immunostimulant, post childbirth to check postpartum hemorrhage and to treat asthma, insomnia, dementia, epilepsy, diabetes, rheumatoid arthritis, asthma, spleen disorder, puerperal fever, leprosy etc. AIM OF THE REVIEW: This review offers essential data focusing on the traditional use, phytochemistry and pharmacological profile of Piper longum thereby identifying research gaps and future opportunities for investigation on this plant.

MATERIALS AND METHODS

This systematic survey was accomplished as per the PRISMA guidelines. The information was collected from books, and electronic search (PubMed, Science Direct, Lilca and Scielo) during 1967-2019.

RESULTS

Many phytochemicals have been identified till date, including alkaloids as its major secondary metabolites (piperine and piperlongumine), essential oil, flavonoids and steroids. These exhibit a wide range of activities including anti-inflammatory, analgesic, anti-oxidant, anti-microbial, anti-cancer, anti-parkinsonian, anti-stress, nootropic, anti-epileptic, anti-hyperglycemic, hepatoprotective, anti-hyperlipidemic, anti-platelet, anti-angiogenic, immunomodulatory, anti-arthritic, anti-ulcer, anti-asthmatic, anthelmintic action, anti-amebic, anti-fungal, mosquito larvicidal and anti-snake venom.

CONCLUSION

Amongst various activities, bioscientific clarification in relation to its ethnopharmacological perspective has been evidenced mainly for anti-amebic, anthelminthic, anti-tumor and anti-diabetic activity. However, despite traditional claims, insufficient scientific validation for the treatment of insomnia, dementia, epilepsy, rheumatoid arthritis, asthma, spleen disorder, puerperal fever and leprosy, necessitate future investigations in this direction. It is also essential and critical to generate toxicological data and pharmacokinetics on human subjects so as to confirm its conceivable bio-active components in the body.

Piperine Alleviates Doxorubicin-Induced Cardiotoxicity via Activating PPAR-γ in Mice

Background

Oxidative stress, inflammation and cardiac apoptosis were closely involved in doxorubicin (DOX)-induced cardiac injury. Piperine has been reported to suppress inflammatory response and pyroptosis in macrophages. However, whether piperine could protect the mice against DOX-related cardiac injury remain unclear. This study aimed to investigate whether piperine inhibited DOX-related cardiac injury in mice.

Methods

To induce DOX-related acute cardiac injury, mice in DOX group were intraperitoneally injected with a single dose of DOX (15 mg/kg). To investigate the protective effects of piperine, mice were orally treated for 3 weeks with piperine (50 mg/kg, 18:00 every day) beginning two weeks before DOX injection.

Results

Piperine treatment significantly alleviated DOX-induced cardiac injury, and improved cardiac function. Piperine also reduced myocardial oxidative stress, inflammation and apoptosis in mice with DOX injection. Piperine also improved cell viability, and reduced oxidative damage and inflammatory factors in cardiomyocytes. We also found that piperine activated peroxisome proliferator-activated receptor-γ (PPAR-γ), and the protective effects of piperine were abolished by the treatment of the PPAR-γ antagonist in vivo and in vitro.

Conclusions

Piperine could suppress DOX-related cardiac injury via activation of PPAR-γ in mice.

The larvicidal activity of natural inspired piperine-based dienehydrazides against Culex pipiens

A series of piperine-based dienehydrazide derivatives were designed and synthesized to be used as insecticides against Culex pipiens. The chemical structure of compound 5n was confirmed by single-crystal x-ray diffraction. Their insecticidal activities of synthesized compounds were tested against third-instar larval of Cx. pipiens at concentrations ranging from 0.1 to 1.2 mg/mL. Among all derivatives, compounds 5a, 5b, 5f, 5g, 5m, 5n, 5o, 5p, and 5u displayed good activities. The final mortality rates at the concentration of 0.75 mg/mL after 48 h treatment, were found to be in the range from 80.00 to 83.33% and with LC₅₀ values ranging from 0.221 to 0.094 mg/mL. These compounds demonstrated higher insecticidal activities than piperine and Deltamethrin (a commercial positive control). Molecular modelling reveals several molecular interactions between synthesized compounds and the substrate binding sits of acetylcholinesterase (AChE) that are predicted to be responsible for its binding and inhibition activity. .

Piperine Is a Mechanism-Based Inactivator of CYP3A

Piperine (PPR) is the representative alkaloid component of the piper species (family: Piperaceae). Our rapid screening study found PPR caused time-dependent inhibition of cytochrome P450s (CYP) 3A and 2D6, and CYP3A was inactivated the most. Further study demonstrated that PPR is a time-, concentration-, and NADPH-dependent inhibitor of CYP3A, and significant loss (49.5% ± 3.9%) of CYP3A activity was observed after 20minute incubations with 80 μM PPR at 37°C. The values of K _I and k _inact were 30.7 μM and 0.041 minutes^-1, respectively. CYP3A competitive inhibitor ketoconazole showed protective effect against the enzyme inactivation. Superoxide dismutase/catalase and GSH displayed minor protection against the PPR-caused enzyme inactivation. Ferricyanide partially reduced the enzyme inhibition by PPR. Additionally, NADPH-dependent formation of reactive metabolites from PPR were found in human liver microsomal incubation mixtures. An ortho-quinone intermediate was trapped by NAC in microsomal incubations with PPR. DM-PPR, demethylene metabolite of PPR, showed weak enzyme inactivation relative to that caused by PPR. It appears that both carbene and ortho-quinone intermediates were involved in the inactivation of CYP3A caused by PPR. SIGNIFICANCE STATEMENT: CYP3A subfamily members (mainly CYP3A4 and CYP3A5) play a critical role in drug metabolism. Piperine (PPR), a methylenedioxyphenyl derivative combined with an unsaturated ketone, is the major active ingredient of pepper. PPR revealed time-, concentration-, and NADPH-dependent inhibitory effect on CYP3A. Carbene and quinone metabolites were both involved in the observed CYP3A inactivation by PPR. Apparently, the unsaturated ketone moiety did not participate in the enzyme inactivation. The present study sounds an alert of potential risk for food-drug interactions.

Piperine as a neuroprotective functional component in rats with cerebral ischemic injury

Long pepper (Piper longum L.) and black pepper (Piper nigrum L.) plants are commonly used as spices around the world and have also been postulated to have medicinal effects. Piperine, as the major alkaloid of P. nigrum and P. longum, has gained wide attention of the medical community and culinary enthusiasts. This study seeks to determine the effects of piperine on neuronal apoptosis in peri-infarcted cerebral cortices of rats with permanent middle cerebral artery occlusion (pMCAO) injury. Evaluation of the different behavioral components was conducted after pMCAO. 2, 3, 5-Triphenyltetrazolium chloride (TTC) was used to evaluate the area of cortical ischemia. Gross histopathological changes, as well as microscopic neuronal changes, were observed in brain tissue samples. The protein expression of Caspase-3, Caspase-9, Bax, Bcl-2, and Cytochrome C (Cyt-c) was analyzed using western blotting. The findings reveal that rats that received piperine treatment show markedly decreased neurological deficit, less ischemia-induced cellular damage, as well as smaller areas of cerebral infarction, with less severe macro and microcellular cerebral structural changes. Western blotting analysis reveals that piperine administration inhibits Bax, while enhancing Bcl-2 expression. The protein expression of Caspase-3, Caspase-9, and Cyt-c was also found to be significantly inhibited. We conclude that piperine may provide several beneficial neuroprotective effects that warrant further investigation.

Piperine-A Major Principle of Black Pepper: A Review of Its Bioactivity and Studies

Piperine is the main compound present in black pepper, and is the carrier of its specific pungent taste, which is responsible for centuries of human dietary utilization and worldwide popularity as a food ingredient. Along with the application as a food ingredient and food preservative, it is used in traditional medicine for many purposes, which has in most cases been justified by modern scientific studies on its biological effects. It has been confirmed that piperine has many bioactive effects, such as antimicrobial action, as well as many physiological effects that can contribute to general human health, including immunomodulatory, hepatoprotective, antioxidant, antimetastatic, antitumor, and many other activities. Clinical studies demonstrated remarkable antioxidant, antitumor, and drug availability-enhancing characteristics of this compound, together with immunomodulatory potential. All these facts point to the therapeutic potential of piperine and the need to incorporate this compound into general health-enhancing medical formulations, as well as into those that would be used as adjunctive therapy in order to enhance the bioavailability of various (chemo)therapeutic drugs.

Piperine ameliorates the severity of fibrosis via inhibition of TGF‑β/SMAD signaling in a mouse model of chronic pancreatitis

Chronic pancreatitis (CP) is characterized by recurrent pancreatic injury, resulting in inflammation and fibrosis. Currently, there are no drugs for the treatment of pancreatic fibrosis associated with CP. Piperine, a natural alkaloid found in black pepper, has been reported to show anti-inflammatory, anti-oxidative, and antitumor activities. Although piperine exhibits numerous properties in regards to the regulation of diverse diseases, the effects of piperine on CP have not been established. To investigate the effects of piperine on CP in vivo, we induced CP in mice through the repetitive administration of cerulein (50 µg/kg) six times at 1-h intervals, 5 times per week, for a total of 3 weeks. In the pre-treatment groups, piperine (1, 5, or 10 mg/kg) or corn oil were administrated orally at 1 h before the first cerulein injection, once a day, 5 times a week, for a total of 3 weeks. In the post-treatment groups, piperine (10 mg/kg) or corn oil was administered orally at 1 or 2 week after the first cerulein injection. Pancreases were collected for histological analysis. In addition, pancreatic stellate cells (PSCs) were isolated to examine the anti-fibrogenic effects and regulatory mechanisms of piperine. Piperine treatment significantly inhibited histological damage in the pancreas, increased the pancreatic acinar cell survival, reduced collagen deposition and reduced pro-inflammatory cytokines and chemokines. In addition, piperine treatment reduced the expression of fibrotic mediators, such as α-smooth muscle actin (α-SMA), collagen, and fibronectin 1 in the pancreas and PSCs. Moreover, piperine treatment reduced the production of transforming growth factor (TGF)-β in the pancreas and PSCs. Furthermore, piperine treatment inhibited TGF-β-induced pSMAD2/3 activation but not pSMAD1/5 in the PSCs. These findings suggest that piperine treatment ameliorates pancreatic fibrosis by inhibiting TGF-β/SMAD2/3 signaling during CP.

Evaluation of Anti-Inflammatory Properties of Herbal Aqueous Extracts and Their Chemical Characterization

Plant extracts are gaining more attention as therapeutic agents against inflammation. In this study, four different widely used herbals were selected, such as holy basil leaf, sesame seed, long pepper, and cubeb pepper. We have evaluated the anti-inflammatory action of an aqueous extract from these herbs and tested their effects on monocyte-derived macrophages (MDMs). MDMs were pre-treated with these extracts individually for 2 h, followed by lipopolysaccharide (LPS) stimulation for 24 h and pro-inflammatory gene expression was analyzed. Also, we studied the effect of these extracts on the oxidation of low-density lipoprotein (LDL) by enzymatic (Myeloperoxidase) and non-enzymatic (copper) reactions. All extracts attenuated LPS-induced inflammation and also were able to inhibit the oxidation of LDL. These beneficial actions of extracts led us to identify molecules present in the extracts. A liquid chromatography-high resolution mass spectrometric analysis was performed to identify the chemical composition of extracts. Wide range of molecules were identified across all the extracts, short-chain organic acids, phenolic acids and derivatives, piperine and its structural homologues, eugenol, rosmarinic acid, flavonoids and their glucosides, and others. This study opens a door for future studies on non-pharmacological natural therapeutics that will be useful for consumers and producers, as well as industries utilizing bioactive compounds.

Effectiveness of novel herbal dentifrice in control of plaque, gingivitis, and halitosis - Randomized controlled trial

Background and aim

Plaque is a common etiological factor for common oral conditions like gingivitis, periodontitis, dental caries and halitosis. We aimed to evaluate the efficacy of a novel herbal dentifrice in control of plaque, gingivitis, and halitosis in comparison to control dentifrice.

Experimental procedure

We conducted a randomized controlled, single center, double-blinded parallel arm clinical trial. Participants were randomly distributed with commercially available herbal dentifrice or control dentifrice. Assessments of plaque, gingivitis, halitosis, unstimulated saliva pH were done at baseline and at one month by a trained and calibrated periodontist. All the participants were given new toothbrushes one week before the start of the study. They were asked to brush with the designated dentifrices for 2–4 min, twice daily for one month.

Results and conclusion

A total of 79 participants were recruited for this study, out of which 75 participants completed the follow-up. Inter-group comparisons of all the variables at baseline showed no significant differences in the mean plaque index, gingival index, halitosis and pH between test and control groups respectively. Intra-group comparisons showed a significant decrease in mean plaque, gingival and halitosis at follow-up than at baseline in both test and control groups. No significant differences between test and control groups were seen in the mean plaque index (P = 0.792), gingival index (P = 0.292), halitosis (P = 0.266), pH (P = 0.742) at follow-up after adjusting the respective baseline scores. The novel herbal dentifrice could be a suitable alternative for the control of plaque, gingivitis, and halitosis.

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Significant decrease in clinical indices at follow-up than baseline in both groups.

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Significant increase in salivary pH at follow-up than baseline in both groups.

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No significant differences were seen clinical indices between test and control.

Phytochemical and pharmacological attributes of piperine: A bioactive ingredient of black pepper

Plants are vital for the wellbeing of humankind in a variety of ways. Some plant extracts contain antimicrobial properties that can treat different pathogens. Most of the world's population relies on medicinal plants and natural products for their primary health care needs. Therefore, there is a growing interest in natural products, medicinal plants, and traditional medicine along with a desire to design and develop novel plant-based pharmaceuticals. These plant-based pharmaceuticals may address the concerns of reduced efficacy of synthetic antibiotics due to the emergence of drug-resistant pathogens. In this regard, some plant extracts from black pepper (Piper nigrum) with antimicrobial properties, including piperine, have the potential to be used as natural dietary supplements together with modern therapeutic approaches. This review highlights possible applications of piperine as the active compound in the fields of rational drug design and discovery, pharmaceutical chemistry, and biomedicine. We discuss different extraction methods and pharmacological effects of the analyzed substance to pave the way for further research strategies and perspectives towards the development of novel herbal products for better healthcare solutions.

Piperine ameliorated lupus nephritis by targeting AMPK-mediated activation of NLRP3 inflammasome

BACKGROUND

Lupus nephritis (LN) is a leading cause of mortality. The activation of NLRP3 inflammasome contributed to LN development and thus became a therapeutic target. Here we assessed the therapeutic potential of piperine, a bioactive compound known to target NLRP3 inflammasome, on LN development both in vivo and in vitro.

METHODS

LN was induced in BALB/c mice via intraperitoneal injection of pristane. Upon treatment with increasing doses of piperine, we assessed renal lesions, measured serum levels of pro-inflammatory cytokines, and examined expressions of key components of NLRP3 inflammasome in kidney. To explore the molecular mechanisms, we treated the proximal tubular epithelial HK-2 cells with lipopolysaccharide (LPS) and ATP, and examined the effects of piperine on pyroptosis and the activation of NLRP3 inflammasome. Furthermore, we assessed the significance of AMPK signaling in piperine functions in HK-2 cells.

RESULTS

In pristane-injected mice, piperine significantly ameliorated LN development in a dose-dependent manner, which was associated with the inhibition of NLRP3 inflammasome and the reduction of serum IL-1β, but not of IL-18 level. In HK-2 cells, piperine potently inhibited pyroptosis and the activation of NLRP3 inflammasome in response to LPS + ATP. The effects of piperine were mediated by blocking AMPK activation, and the AMPK agonist metformin bypassed the activities of piperine, and resumed pyroptosis as well as the activation on NLRP3 inflammasome.

CONCLUSIONS

By targeting AMPK, piperine significantly suppressed the activation of NLRP3 inflammasome, inhibited the release of pro-inflammatory cytokines, blocked the pyroptosis of tubular epithelial cells, and thus suppressed the development of LN.

Black pepper and its bioactive constituent piperine: promising therapeutic strategies for oral lichen planus

Oral lichen planus (OLP) is a common T cell-mediated chronic inflammatory disease with malignant potential and unclear etiology. The present study suggests that antigen-specific mechanisms in which dentritic cells, T lymphocytes and NF-κB signaling pathway play critical roles, are involved in the pathogenesis of OLP. Additionally, it has been indicated that altered expression of cyclooxygenase 2 (COX-2) and imbalanced oxidant-antioxidant status as well as psychological issue may act as promoters to the development of OLP. Therapies for OLP are primarily aimed to control symptoms and a specific cure is not yet available. Black pepper and its principle bioactive compound piperine have been reported to possess remarkable pharmacological activities. Not only has piperine been evidenced to exhibit repressive effects on the maturation of dentritic cells, the proliferation, activation and function of T lymphocytes as well as the NF-κB signaling pathway, but also to suppress the overproduction of COX-2 and weaken the oxidative stress. Furthermore, piperine might be a possible agent for alleviating psychological disorders and preventing carcinogenesis. Given all these into consideration, piperine may be a novel and effective therapeutic strategy for OLP.

Characterization of piperine metabolites in rats by ultra-high-performance liquid chromatography with electrospray ionization quadruple time-of-flight tandem mass spectrometry

RATIONALE

Piperine is a major constituent of Piper nigrum L. and is a naturally bioactive alkaloid. Structural changes in piperine have been shown to result in different biological effects. The present study aims to investigate piperine metabolites in rat plasma, bile, urine, and feces after oral administration.

METHODS

The metabolic pathway of piperine in vivo was investigated using ultra-high-performance liquid chromatography (UHLPC) combined with electrospray ionization quadruple time-of-flight tandem mass spectrometry (QTOF-MS). Piperine metabolites were found and identified by fragmentation patterns and accurate mass measurements.

RESULTS

The 12 metabolites detected and identified were divided into three groups: methylenedioxycyclic ring-opening metabolites (M01-M08), methylenedioxycyclic ring-oxidizing metabolites (M09-M11), and piperidine ring-cleavage metabolites (M12). Seven piperine metabolites, including M02, M03, M04, M05, M09, M10 and M11, were reported for the first time in the literature.

CONCLUSIONS

Results showed that the principal metabolism pathways of piperine in rat were reduction and demethylation after ring-opening, and that UHPLC/QTOF-MS can serve as an important analytical platform to gather the piperine metabolism profile. Copyright © 2017 John Wiley & Sons, Ltd.

The anti-allergic and anti-inflammatory effects of Benjakul extract (a Thai traditional medicine), its constituent plants and its some pure constituents using in vitro experiments

Benjakul (BJK), a Thai traditional medicine preparation, has long been used for balanced health, controlled abnormal of element in the body, carminative, and relief of flatulence. It is composed of five plants: Piper interruptum Opiz., Piper longum L., Piper sarmentosum Roxb., Plumbago indica L., and Zingiber officinale Roscoe. The ethanolic extracts of BJK, its five individual plants, and pure constituents of BJK were investigated for their anti-allergic activity using immunoglobulin E (IgE)-sensitized β-hexosaminidase in the rat basophilic leukemia-2H3 (RBL-2H3) cells and anti-inflammatory activity using lipopolysaccharide (LPS)-induced nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α) in the murine macrophage (RAW 264.7) cells. The ethanolic extracts of BJK showed anti-allergic activity (IC₅₀=12.69μg/ml) and exhibited potent NO inhibitory effect (IC₅₀=16.60μg/ml), but inactive on TNF-α release. Moreover, 6-shogaol and plumbagin, two pure compounds from BJK, showed higher anti-allergic activity than the ethanolic BJK extract with IC₅₀ values of 0.28 and 4.03μg/ml, respectively. These compounds were significantly higher than chlorpheniramine (CPM), standard drug, with IC₅₀ value of 17.98μg/ml. Determination of the anti-inflammatory activity by measuring the inhibition of NO production presented that plumbagin and 6-shogaol exhibited higher than crude BJK extract with IC₅₀ values of 0.002 and 0.92μg/ml, respectively. In particular, plumbagin also showed higher anti-inflammatory than prednisolone, positive control, with IC₅₀ value of 0.59μg/ml. 6-Shogaol also showed inhibitory effect on TNF-α release (IC₅₀=9.16μg/ml). These preliminary results may provide some scientific support for the use of BJK for the anti-allergic treatment and inflammatory disorders through the inhibition of NO production.

Piperine, a Pungent Alkaloid from Black Pepper, Inhibits B Lymphocyte Activation and Effector Functions

Piperine has several well-documented anti-inflammatory properties; however, little is known regarding its effect on humoral immunity. In this study, we describe the immunosuppressive effect of piperine on B lymphocytes, which are integral to the humoral immune response. Mouse B cells were cultured in the absence or presence of non-cytotoxic concentrations (25, 50, and 100 μM) of piperine during T-dependent or T-independent stimulation. Piperine inhibited B cell proliferation by causing G0/G1 phase cell cycle arrest in association with reduced expression of cyclin D2 and D3. The inhibitory effect of piperine was not mediated through transient receptor potential vanilloid-1 ion channel (TRPV1) because piperine also inhibited the proliferation of B cells from TRPV1-deficient mice. Expression of class II major histocompatibility complex molecules and costimulatory CD40 and CD86 on B lymphocytes was reduced in the presence of piperine, as was B cell-mediated antigen presentation to syngeneic T cells. In addition, piperine inhibited B cell synthesis of interleukin (IL)-6 and IL-10 cytokines, as well as IgM, IgG2b, and IgG3 immunoglobulins. The inhibitory effect of piperine on B lymphocyte activation and effector function warrants further investigation for possible application in the treatment of pathologies related to inappropriate humoral immune responses. Copyright © 2017 John Wiley & Sons, Ltd.

Black garlic: A critical review of its production, bioactivity, and application

Black garlic is obtained from fresh garlic (Allium sativum L.) that has been fermented for a period of time at a controlled high temperature (60–90°C) under controlled high humidity (80–90%). When compared with fresh garlic, black garlic does not release a strong offensive flavor owing to the reduced content of allicin. Enhanced bioactivity of black garlic compared with that of fresh garlic is attributed to its changes in physicochemical properties. Studies concerning the fundamental findings of black garlic, such as its production, bioactivity, and applications, have thus been conducted. Several types of black garlic products are also available in the market with a fair selling volume. In this article, we summarize the current knowledge of changes in the components, bioactivity, production, and applications of black garlic, as well as the proposed future prospects on their possible applications as a functional food product.

Piperine Suppresses Pyroptosis and Interleukin-1β Release upon ATP Triggering and Bacterial Infection

Piperine is a phytochemical present in black pepper (Piper nigrum Linn) and other related herbs, possessing a wide array of pharmacological activities including anti-inflammatory effects. Previously, we demonstrated that piperine has therapeutic effects on bacterial sepsis in mice, but the underlying mechanism has not been fully elucidated. In this study, we aimed to investigate the influences of piperine on pyroptosis in murine macrophages. The results showed that piperine dose-dependently inhibited ATP-induced pyroptosis, thereby suppressing interleukin-1β (IL-1β) or high mobility group box-1 protein (HMGB1) release in LPS-primed bone marrow-derived macrophages and J774A.1 cells. Accompanying this, ATP-induced AMP-activated protein kinase (AMPK) activation was greatly suppressed by piperine, whereas AMPK agonist metformin counteracted piperine’s inhibitory effects on pyroptosis. Moreover, piperine administration greatly reduced both peritoneal and serum IL-1β levels in the mouse model intraperitoneally infected with Escherichia coli, suggestive of suppressing systemic inflammation and pyroptosis. Our data indicated that piperine could protect macrophages from pyroptosis and reduced IL-1β and HMGB1 release by suppressing ATP-induced AMPK activation, suggesting that piperine may become a potential therapeutic agent against bacterial sepsis.

Anti-Inflammatory Effects of Liriope platyphylla in LPS-Stimulated Macrophages and Endotoxemic Mice

In the present study, the anti-inflammatory and antisepticemic activities of a water extract of Liriope platyphylla (LP) were investigated. We first estimated the scavenging activity of DPPH and the hydroxyl radical and total phenolic contents of LP. Results indicated that LP, a rich source of phenolic compounds, showed a remarkable radical scavenging capacity. A MTT assay showed that LP treatment did not affect the toxicity against the RAW 264.7 macrophage cells, up to the concentration of 500[Formula: see text][Formula: see text]g/mL. Treatment of LP significantly attenuated the production of inflammatory mediators, such as nitric oxide (NO), interleukin-6 (IL-6), tumor-necrosis factor (TNF)-[Formula: see text] and prostaglandin (PG)E2 in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages cells. Moreover, LP contributed to the down-regulation of inducible NO synthase (iNOS) and TNF-[Formula: see text] mRNA expression, as well as cyclooxygenase-2 (COX-2) protein expression. A western blotting assay further showed that LP inhibited activation of mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-[Formula: see text]B. In an animal experiment using an LPS-induced septicemia model in C57BL/6 mice, oral administration of LP (40[Formula: see text]mg/kg body weight) markedly reduced the level of TNF-[Formula: see text] and IL-6 in serum and protected against LPS-induced lethal shock in mice. Taken together, the results of treatments of LP on inhibited LPS-induced inflammatory responses in both in vitro and in vivo models and indicate it may be a promising neutraceutical or medicinal agent to prevent or cure inflammation-related disease.

Piperine metabolically regulates peritoneal resident macrophages to potentiate their functions against bacterial infection

Pepper, a daily-used seasoning for promoting appetite, is widely used in folk medicine for treating gastrointestinal diseases. Piperine is the major alkaloid in pepper and possesses a wide range of pharmacological activities. However, the mechanism for linking metabolic and medicinal activities of piperine remains unknown. Here we report that piperine robustly boosts mTORC1 activity by recruiting more system L1 amino acid transporter (SLC7A5/SLC3A2) to the cell membrane, thus promoting amino acid metabolism. Piperine-induced increase of mTORC1 activity in resident peritoneal macrophages (pMΦs) is correlated with enhanced production of IL-6 and TNF-α upon LPS stimulation. Such an enhancement of cytokine production could be abrogated by inhibitors of the mTOR signaling pathway, indicating mTOR's action in this process. Moreover, piperine treatment protected resident pMΦs from bacterium-induced apoptosis and disappearance, and increased their bacterial phagocytic ability. Consequently, piperine administration conferred mice resistance against bacterial infection and even sepsis. Our data highlight that piperine has the capacity to metabolically reprogram peritoneal resident macrophages to fortify their innate functions against bacterial infection.

Optimization of the fermentation process of Cordyceps sobolifera Se-CEPS and its anti-tumor activity in vivo

Background

Cordyceps sobolifera (C. sobolifera) isolated from cicadae was used as the starting fungus to produce selenium-enriched C. sobolifera extracellular polysaccharide (Se-CEPS). An orthogonal experimental design based on a single-factor experiment was used to optimize the C. sobolifera fermentation conditions, including the potato juice, peptone, and KH₂PO₄ concentrations. Ultraviolet (UV) and infrared (IR) analyses of CEPS and Se-CEPS were conducted, as well as an in vivo anti-tumor analysis.

Results

Under optimal conditions (i.e., 40 potato juice, 0.4 KH₂PO₄, and 0.5 % peptone), the fermentation yield of Se-CEPS was 5.64 g/L. UV and IR spectra showed that Se-CEPS contained a characteristic absorption peak of a selenite Se = O double bond, demonstrating the successful preparation of Se-CEPS. Activity tests showed that Se-CEPS improved the immune organ index, serum cytokine content, and CD8⁺ and CD4⁺ T lymphocyte ratio in colon cancer CT26 tumor-bearing mice, thereby inhibiting tumor growth. When combined with 5-FU, Se-CEPS reduced the toxicity and enhanced the function of 5-FU.

Conclusion

The result of these experiments indicated that orthogonal experimental design is a promising method for the optimization of Se-CEPS production, and the Se-CEPS from C. sobolifera can improve the anti-tumor capacity of mice.

Electronic supplementary material

The online version of this article (doi:10.1186/s13036-016-0029-0) contains supplementary material, which is available to authorized users.

Piperine from black pepper inhibits activation-induced proliferation and effector function of T lymphocytes

Piperine is a major alkaloid component of black pepper (Piper nigrum Linn), which is a widely consumed spice. Here, we investigated the effect of piperine on mouse T lymphocyte activation. Piperine inhibited polyclonal and antigen-specific T lymphocyte proliferation without affecting cell viability. Piperine also suppressed T lymphocyte entry into the S and G2 /M phases of the cell cycle, and decreased expression of G1 -associated cyclin D3, CDK4, and CDK6. In addition, piperine inhibited CD25 expression, synthesis of interferon-γ, interleukin (IL)-2, IL-4, and IL-17A, and the generation of cytotoxic effector cells. The inhibitory effect of piperine on T lymphocytes was associated with hypophosphorylation of Akt, extracellular signal-regulated kinase, and inhibitor of κBα, but not ZAP-70. The ability of piperine to inhibit several key signaling pathways involved in T lymphocyte activation and the acquisition of effector function suggests that piperine might be useful in the management of T lymphocyte-mediated autoimmune and chronic inflammatory disorders.

Piperine impairs the migration and T cell-activating function of dendritic cells

Piperine, a major alkaloid found in the fruits of black and long pepper plants, has anti-inflammatory properties; however, piperine's effect on dendritic cell (DC) migration and T cell-activating function has not been investigated. Bone marrow-derived mouse DCs that were matured in the presence of 100 μM piperine showed reduced in vitro migration in response to CCL21, as well as reduced in vivo migration to lymph nodes. In addition, piperine-treated DCs had reduced CCR7 expression and elevated CCR5 expression, as well as reduced expression of CD40 and class II major histocompatibility complex molecules and decreased nuclear accumulation of RelB. DC production of interleukin (IL)-6, tumor necrosis factor α, and monocyte chemoattractant protein-1 in response to lipopolysaccharide stimulation was also reduced following piperine treatment. Exposure to piperine during maturation therefore caused DCs to retain an immature phenotype, which was associated with a reduced capacity to promote T cell activation since co-culture of ovalbumin (OVA323-339)-specific T cells with OVA323-339-pulsed DCs that were previously matured in the presence of piperine showed reduced interferon-γ and IL-2 expression. OVA323-339-specific T cell proliferation was also reduced in vivo in the presence of piperine-treated DCs. Inhibition of DC migration and function by piperine may therefore be a useful strategy to down-regulate potentially harmful DC-driven T cell responses to self-antigens and transplantation antigens.

Neuroprotective effects of piperine on the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinson's disease mouse model

Parkinson's disease (PD) is second only to Alzheimer's disease as the most common and debilitating age-associated neurodegenerative disorder. Currently, no therapy has been shown to unequivocally retard or arrest the progression of the disease. The aim of the present study was to investigate the protective effect of piperine on the 1-methyl-4-phenyl-1,2,3,6‑tetrahydropyridine (MPTP)-induced Parkinson's mouse model. For MPTP treatment, the animals received repeated intraperitoneal injections (i.p.) of MPTP (30 mg/kg) solution for 7 days. Piperine (10 mg/kg) was administered orally for 15 days including 8 days of pretreatment. Motor behavior analysis was conducted with the rotarod test. The Morris water maze (MWM) was used to assess the cognitive learning ability of the mice. A histological examination was subsequently conducted. The results ddemonstrate that piperine treatment attenuated MPTP-induced deficits in motor coordination and cognitive functioning. Piperine also prevented MPTP-induced decreases in the number of tyrosine hydroxylase-positive cells in the substantia nigra. Additionally, piperine reduced the number of activated microglia, expression of cytokine IL-1β, and oxidative stress following MPTP treatment. An anti-apoptotic property of piperine was identified by maintaining the balance of Bcl-2/Bax. In conclusion, the results show that piperine exerts a protective effect on dopaminergic neurons via antioxidant, anti-apoptotic, and anti-inflammatory mechanisms in an MPTP-induced mouse model of PD. Thus, piperine is a potential therapeutic treatment for PD.

Discovery of Some Piperine-Based Phenylsulfonylhydrazone Derivatives as Potent Botanically Narcotic Agents

By structural modification of piperine, some piperine-based phenylsulfonylhydrazone derivatives exhibited an unprecedented and potent narcotic activity against the oriental armyworm, Mythimna separata (Walker). The ND50 values of compounds 6c and 6e against the third-instar larvae of M. separata, which were more potent than those of wilfortrine and wilforgine, were 0.0074 μmol (after 3.5 h), and 0.0075 μmol (after 7 h) per larvae, respectively. By transmission electron microscope, it demonstrated that mitochondria were vacuolated and swollen in the ganglion cell of M. separata after treatment with 6c. More importantly, 6c selectively displayed the inhibition activity on acetylcholine esterase (AchE) of M. separata. This work paved the way for further studying the insecticidal mechanism of 6c as a new and promising botanical narcotic agent.

LC-HRMS determination of piperine on rat dried blood spots: A pharmacokinetic study

A liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was developed and validated for the determination of piperine (PPR) on dried blood spots (DBS). DBS samples were prepared by spiking the whole blood with analyte to produce 30 µL of blood spots on specimen collection cards. Chromatographic separation was achieved on an Atlantis dC₁₈ column using acetonitrile and water (0.1% formic acid) (85:15, v/v) as mobile phase in an isocratic mode of elution at a flow rate of 0.75 mL/min. MS detection was carried out in electrospray positive ion mode for the target ions and monitored at m/z 286.1465 for PPR and 272.1303 for the internal standard (IS). The developed method exhibited a linear dynamic range over 0.01-2000 ng/mL for PPR on DBS. The overall extraction recovery of PPR from DBS was 92.5%. Influence of hematocrit and spot volume on DBS was also evaluated and found to be well within the acceptable limits. The method was successfully applied to pharmacokinetic studies of PPR in rats.

Piperine inhibit inflammation, alveolar bone loss and collagen fibers breakdown in a rat periodontitis model

BACKGROUND AND OBJECTIVE

Piperine exhibits anti-inflammatory activity, and has a long history of medicinal use. The objective of this study was to investigate the protective effects of piperine on inflammation, alveolar bone and collagen fibers in experimental periodontitis. We evaluated the related expression of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, matrix metalloproteinase (MMP)-8 and MMP-13 to enhance insight into these effects.

MATERIAL AND METHODS

Thirty-two Wistar rats were divided into four groups of eight animals each: control group, periodontitis group, periodontitis plus 50 mg/kg piperine group and periodontitis plus 100 mg/kg piperine group. Histopathologic changes were detected by hematoxylin and eosin staining. Alveolar bone loss and trabecula microstructures were evaluated by micro-computed tomography. Changes in collagen fibers were assessed by picrosirius red staining. Western blot analysis was conducted to determine the levels of IL-1β, TNF-α, MMP-8 and MMP-13.

RESULTS

Piperine clearly inhibited alveolar bone loss and reformed trabecula microstructures in a dose-dependent manner. Histological staining showed that piperine significantly reduced the infiltration of inflammation in soft tissues. Both doses of piperine limited the fractions of degraded areas in collagen fibers. Piperine (100 mg/kg) significantly downregulated the expressions of IL-1β, MMP-8 and MMP-13 in periodontitis, but not that of TNF-α.

CONCLUSION

Piperine displays significantly protective effects on inflammation, alveolar bone loss, bone microstructures and collagen fiber degradation in experimental periodontitis. The effects may be ascribed to its inhibitory activity on the expressions of IL-1β, MMP-8 and MMP-13.