A randomized, double-blind, placebo-controlled study to evaluate the benefits of a standardized Nigella sativa oil containing 5% thymoquinone in reducing the symptoms of seasonal allergy.

BACKGROUND: Allergic rhinitis (AR) or seasonal allergy characterized by sneezing, nasal congestion, nasal itching, and nasal discharge, triggered by immune reactions to environmental allergens. Present day customers also monitor the personal improvements in the area of Evidence-Based natural medicines/supplements. METHODS: A randomized, double-blind, placebo-controlled study was conducted on 65 participants aged 18 to 60 years having 2 or more allergic symptoms like sneezing, rhinorrhoea, nasal obstruction, and nasal itching for a cumulative period greater than 1 hour per day. The study participants received a capsule of NSO (250 mg) with 2.5 mg piperine (BioPerine) as a bioavailability enhancer or a placebo, twice a day, after food for 15 days. The primary objectives were evaluated by mean change in Total Nasal Symptom Score and the duration of AR symptoms per day from baseline to Day 15. Secondary endpoints were changes in Total Ocular Symptoms Score, AR symptom frequency and severity, serum Immunoglobulin E levels, and Patient Global Impression of Change scale. Adverse events were monitored throughout the study. RESULTS: Sixty-five patients were enrolled and all of them completed the study, N = 33 in NSO and N = 32 in placebo. A significant reduction in Total Nasal Symptom Score and Total Ocular Symptoms Score was observed in the NSO group compared to the placebo, highlighting the potential of NSO in alleviating AR symptoms. The episodes of AR symptoms per day and the frequency of symptoms in 24 hours reduced significantly in 15 days in both groups, but the extent of improvement was significantly higher in NSO compared to placebo. Improvement in Patient Global Impression of Change was also significantly better in NSO compared to the placebo. Serum Immunoglobulin E levels decreased in NSO but were not significantly different from placebo. No clinically significant changes were observed in vital signs, liver and renal function, lipid profile, hematology, fasting blood sugar, or urine analysis at the end of the study. CONCLUSION: The result of the study demonstrates that NSO 250 mg with 2.5 mg piperine is an effective and well-tolerated supplement for the management of AR symptoms.

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.

Piperine attenuates hepatic ischemia/reperfusion injury via suppressing the TLR4 signaling cascade in mice.

Piperine, the major active substance in black pepper, has been shown to have anti-inflammatory and antioxidant effects in several ischemic diseases. However, the role of piperine in hepatic ischemia/reperfusion injury (HIRI) and its underlying mechanisms remain unclear. In this study, the mice were administered piperine (30 mg/kg) intragastric administration before surgery. After 24 h of hepatic ischemia-reperfusion, liver histopathological evaluation, serum transaminase measurements, and TUNEL analysis were performed. The infiltration of inflammatory cells and production of inflammatory mediators in the liver tissue were determined by immunofluorescence and immunohistochemical staining. The protein levels of toll-like receptor 4 (TLR4) and related proteins such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukin-1 receptor-associated kinase 1 (IRAK1), p65, and p38 were detected by western blotting. The results showed that plasma aminotransferase (ALT), aspartate aminotransferase (AST), hepatocyte apoptosis, oxidative stress, and inflammatory cell infiltration significantly increased in HIRI mice. Piperine pretreatment notably repaired liver function, improved the histopathology and apoptosis of liver cells, alleviated oxidative stress injury, and reduced inflammatory cell infiltration. Further analysis showed that piperine attenuated tumor necrosis factor-a (TNF-α) and interleukin 6 (IL-6) production and reduced TLR4 activation and phosphorylation of IRAK1, p38, and NF-κB in HIRI. Piperine has a protective effect against HIRI through the TLR4/IRAK1/NF-κB signaling pathway and may be a safer option for future clinical treatment and prevention of ischemia-related diseases.

Overview of Curcumin and Piperine Effects on Glucose Metabolism: The Case of an Insulinoma Patient's Loss of Consciousness.

The hypoglycemic properties of curcumin supplements in therapeutic doses are well-known and may represent a useful tool for the treatment of chronic diseases such as metabolic syndrome, insulin resistance and type 2 diabetes. The poor bioavailability of curcumin can be improved with the concomitant administration of piperine, with no severe adverse effects on glycemia reported so far in the literature. In this article, we further discuss a previously reported case of a helicopter pilot, affected by grade I obesity who, under curcumin and piperine treatment, experienced a transient loss of consciousness (TLOC), during a low-altitude flight. This episode led to a diagnosis of insulinoma, previously asymptomatic. We hypothesized that the combined effects of curcumin and piperine might have caused a severe hypoglycemic episode and subsequent TLOC. Therefore, further studies should be conducted to evaluate the safety of curcumin and piperine supplementation in subjects with impaired glucose metabolism and insulin secretion.

Echinacea purpurea against neuropathic pain: Alkamides versus polyphenols efficacy.

Chemotherapy-induced neuropathy represents the main dose-limiting toxicity of several anticancer drugs, such as oxaliplatin, leading to chronic pain and an impairment of the quality of life. Echinacea purpurea n-hexane extract (EP4 -RE ; rich in alkamides) and butanolic extract (EP4 -RBU ; rich in polyphenols) have been characterized and tested in an in vivo model of oxaliplatin-induced neuropathic pain, addressing the endocannabinoid system with alkamides and counteracting the redox imbalance with polyphenols. Thermal hypersensitivity was evaluated by the Cold Plate test. EP4 -RE showed a dose-dependent anti-hyperalgesic profile. The extract was more effective than its main constituent, dodeca-2 E,4 E,8Z,10 E/Z-tetraenoic acid isobutylamide (18 mg kg-1 , twofold to equimolar EP4 -RE 30 mg kg-1 ), suggesting a synergy with other extract constituents. Administration of cannabinoid type 2 (CB2) receptor-selective antagonist completely blocked the anti-allodynic effect of EP4 -RE , differently from the antagonism of CB1 receptors. EP4 -RBU (30 mg kg-1 ) exhibited anti-neuropathic properties too. The effect was mainly exerted by chicoric acid, which administered alone (123 µg kg-1 , equimolar to EP4 -RBU 30 mg kg-1 ) completely reverted oxaliplatin-induced allodynia. A synergy between different polyphenols in the extract had not been highlighted. Echinacea extracts have therapeutic potential in the treatment of neuropathic pain, through both alkamides CB2-selective activity and polyphenols protective properties.

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.

A zebrafish HCT116 xenograft model to predict anandamide outcomes on colorectal cancer.

Colon cancer is one of the leading causes of death worldwide. In recent years, cannabinoids have been extensively studied for their potential anticancer effects and symptom management. Several in vitro studies reported anandamide's (AEA) ability to block cancer cell proliferation and migration, but evidence from in vivo studies is still lacking. Thus, in this study, the effects of AEA exposure in zebrafish embryos transplanted with HCT116 cells were evaluated. Totally, 48 hpf xenografts were exposed to 10 nM AEA, 10 nM AM251, one of the cannabinoid 1 receptor (CB1) antagonist/inverse agonists, and to AEA + AM251, to verify the specific effect of AEA treatment. AEA efficacy was evaluated by confocal microscopy, which demonstrated that these xenografts presented a smaller tumor size, reduced tumor angiogenesis, and lacked micrometastasis formation. To gain deeper evidence into AEA action, microscopic observations were completed by molecular analyses. RNA seq performed on zebrafish transcriptome reported the downregulation of genes involved in cell proliferation, angiogenesis, and the immune system. Conversely, HCT116 cell transcripts resulted not affected by AEA treatment. In vitro HCT116 culture, in fact, confirmed that AEA exposure did not affect cell proliferation and viability, thus suggesting that the reduced tumor size mainly depends on direct effects on the fish rather than on the transplanted cancer cells. AEA reduced cell proliferation and tumor angiogenesis, as suggested by socs3 and pcnp mRNAs and Vegfc protein levels, and exerted anti-inflammatory activity, as indicated by the reduction of il-11a, mhc1uba, and csf3b mRNA. Of note, are the results obtained in groups exposed to AM251, which presence nullifies AEA's beneficial effects. In conclusion, this study promotes the efficacy of AEA in personalized cancer therapy, as suggested by its ability to drive tumor growth and metastasis, and strongly supports the use of zebrafish xenograft as an emerging model platform for cancer studies.

Harnessing the mitochondrial integrity for neuroprotection: Therapeutic role of piperine against experimental ischemic stroke.

Ischemic stroke (IS) is a rapidly increasing global burden and is associated with severe neurological decline and mortality. There is urgent requirement of the efforts, aimed to identify therapeutic strategies that are effective in clinic to promote significant recovery from IS. Studies have shown that mitochondria mediated neuroprotection can be a competent target against ischemic damage. Therefore, we examined whether mitochondrial impairment is regulated by Piperine (PIP), an alkaloid of Piper Longum, which has neuroprotective activity against ischemic brain injury. In this study, transient middle cerebral artery occlusion (tMCAO) surgery was performed on male Wistar rats for 90 min followed by 22.5 h of reperfusion for mimicking the IS condition. This study consisted of three groups: sham, tMCAO and tMCAO + PIP (10 mg/kg b.wt., p.o/day for 15 days), and studied for behavioral tests, infarct volume, brain pathological changes, mitochondrial dysfunction, inflammation alongwith cell survival status. PIP pre-treatment showed reduction in neurological alterations and infarct volume. In addition, PIP pre-treatment suppressed the mitochondrial dysfunction and might have anti-apoptotic potential by preventing Cytochrome c (Cyt c) release from mitochondria to cytoplasm and caspase 3 activation. It also regulates pro-apoptotic, Bax and anti-apoptotic, Bcl-2 proteins accompanied by glial fibrillary acidic protein (GFAP) positive cells in cortex region. Quantitative Reverse transcription-polymerase chain reaction (qRT-PCR) results also showed that PIP reduced the expression of pro-inflammatory protein, interleukin-1 ß (IL-1ß) and enhanced cell survival by restoring the activity of brain derived neurotrophic factor (BDNF) and its transcription protein, cAMP response element binding protein (CREB). Taken together, PIP reduced the mitochondrial dysfunction, neurological impairment, and enhanced neuronal survival. In conclusion, our findings reinforce PIP as an effective neuroprotective agent and provide important evidence about its role as a potential target to serve as a promising therapy for treatment of IS.

Inhibition of α-glucosidase and α-amylase by herbal compounds for the treatment of type 2 diabetes: A validation of in silico reverse docking with in vitro enzyme assays.

BACKGROUND: α-Amylase and α-glucosidase are important therapeutic targets for the management of type 2 diabetes mellitus. The inhibition of these enzymes decreases postprandial hyperglycemia. In the present study, compounds found in commercially available herbs and spices were tested for their ability to inhibit α-amylase and α-glucosidase. These compounds were acetyleugenol, apigenin, cinnamic acid, eriodictyol, myrcene, piperine, and rosmarinic acid. METHODS: The enzyme inhibitory nature of the compounds was evaluated using in silico docking analysis with Maestro software and was further confirmed by in vitro α-amylase and α-glucosidase biochemical assays. RESULTS: The relationships between the in silico and in vitro results were well correlated; a more negative docking score was associated with a higher in vitro inhibitory activity. There was no significant (P > .05) difference between the inhibition constant (Ki ) value of acarbose, a widely prescribed α-glucosidase and α-amylase inhibitor, and those of apigenin, eriodictyol, and piperine. For α-amylase, there was no significant (P > .05) difference between the Ki value of acarbose and those of apigenin, cinnamic acid, and rosmarinic acid. The effect of the herbal compounds on cell viability was assessed with the sulforhodamine B (SRB) assay in C2C12 and HepG2 cells. Acetyleugenol, cinnamic acid, myrcene, piperine, and rosmarinic acid had similar (P > .05) IC50 values to acarbose. CONCLUSIONS: Several of the herbal compounds studied could regulate postprandial hyperglycemia. Using herbal plants has several advantages including low cost, natural origin, and easy cultivation. These compounds can easily be consumed as teas or as herbs and spices to flavor food.

Cytotoxicity of fagaramide derivative and canthin-6-one from Zanthoxylum (Rutaceae) species against multidrug resistant leukemia cells.

In our continuous search for cytotoxic compounds from the genus Zanthoxylum, chromatographic separation of the MeOH/CH2Cl2 (1:1) extract of Z. chalybeum yielded one new alkamide; 4-(isoprenyloxy)-3-methoxy-3,4-deoxymethylenedioxyfagaramide (1) and a known one; fagaramide (2). Similarly, from the MeOH/CH2Cl2 (1:1) extract of the stem bark of Z. parachanthum four known compounds; canthin-6-one (3), dihydrochelerythrine (4), lupeol (5) and sesamin (6) were isolated. Characterization of the structures of these compounds was achieved using spectroscopic techniques (NMR and MS). Using resazurin reduction assay 1, 3 and 6 displayed moderate cytotoxicity with IC50 values below 50 µM against the drug sensitive CCRF-CEM and multidrug-resistant CEM/ADR5000 leukemia cell lines. It is interesting to note that 3 was more active than the standard drug, doxorubicin against CEM/ADR5000 leukemia cells. Compounds 3 and 6 showed good selectivity on leukemia cells than normal cells. In future studies 3 should be tested against a panel of drug resistant human cells.

Piperine: A review of its biological effects.

Medicinal plants have been used for years as a source of food, spices, and, in traditional medicine, as a remedy to numerous diseases. Piper nigrum, belonging to the family Piperaceae is one of the most widely used spices all over the world. It has a distinct sharp flavor attributed to the presence of the phytochemical, piperine. Apart from its use as a spice, P. nigrum is frequently used for medicinal, preservation, and perfumery purposes. Black pepper contains 2-7.4% of piperine, varying in content is associated with the pepper plant. Piperine displays numerous pharmacological effects such as antiproliferative, antitumor, antiangiogenesis, antioxidant, antidiabetic, anti-obesity, cardioprotective, antimicrobial, antiaging, and immunomodulatory effects in various in vitro and in vivo experimental trials. Furthermore, piperine has also been documented for its hepatoprotective, anti-allergic, anti-inflammatory, and neuroprotective properties. This review highlights and discusses the medicinal and health-promoting effects of piperine, along with possible mechanisms of its action in health promotion and disease prevention. In addition, the present review summarizes the recent literature related to piperine as a therapeutic agent against several diseases.

Propitious Profile of Peppery Piperine.

BACKGROUND: Piperine is a key bioactive alkaloid found in plants of piperaceae family. The compound possesses various medicinal and pharmacological activities (cholesterol-lowering, anti-cancer, Alzheimer's disease etc.). Owing to its various target receptors (TRPV1, P-gp, CYP3A4 etc.) and several mechanisms, piperine has been studied as bio-enhancer for other drugs and its role has been evidenced in the literature. When administered with other drugs, it increases the absorption of other drugs, thereby reducing the dose and dose-related toxic potential. There are various mechanisms of piperine as a bio-enhancer and the common ones are i) prevention of efflux of drug molecules out of the cells; ii) decreased metabolism of drugs, thereby prolonging the halflife of drugs resulting in reduced urinary excretion. The detailed mechanism indicating the bio-enhancing role of piperine along with various target receptors has not been comprehensively summarised to date. METHODS: Literature related to the molecular, enzymatic and receptor targets of piperine were studied, and database was collected using various search engines such as j-gate, google scholar, scihub, pubmed, sciencedirect, etc. The literature related to therapeutic activities of piperine and its bio-enhancer role for other drugs has been thoroughly studied and compiled in brief. RESULTS: A detailed summary of piperine targets, along with related mechanisms, has been stated. A brief therapeutic profile of piperine alone has been produced with supporting literature. Piperine role as a potential bio-enhancer for other drugs has been summarized. CONCLUSION: Piperine is a fascinating molecule of natural origin with several modes of its action, not only possesses its own therapeutic activity but also enhances the therapeutic efficacy of other synthetic and natural drug molecules. Combination dosage forms of various API incorporating piperine as a bio-enhancer can be a potential area of thrust for upcoming drug design and development.

Protective mechanisms of piperine against acetaminophen-induced hepatotoxicity may be mediated through TGFBRAP1.

OBJECTIVE: To investigate the possible protective mechanisms of piperine against acetaminophen (APAP)-induced hepatotoxicity in mice. MATERIALS AND METHODS: Mice were given APAP (650 mg/kg i.p. once) with or without pretreatment with piperine (50 mg/kg/day orally for 3 days). RESULTS: APAP caused liver toxicity as indicated by increased serum alanine aminotransferase and liver microscopic pathology, decreased hepatic superoxide dismutase and glutathione reductase activities, without affecting nuclear factor erythroid 2-related factor 2 (Nrf2) expression. APAP administration induced inflammation and apoptosis manifested as increased NF-κB p65 and dysregulation of caspase 3/Bcl2 expression, respectively. In addition, APAP increased the expression of transforming growth factor-ß receptor-associated binding protein 1 (TGFBRAP1). On the other hand, pretreatment with piperine improved liver function and structure, reserved hepatic antioxidative defense, and attenuated inflammatory and apoptotic markers. Interestingly, piperine administration enhanced hepatic TGFBRAP1 expression compared to APAP alone. CONCLUSIONS: The hepatoprotective effects of piperine against APAP are mediated via its antioxidant, anti-inflammatory, and anti-apoptotic effects, in addition to regulation of TGFBRAP1.

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.

Hydroxy-α-sanshool Possesses Protective Potentials on H2O2-Stimulated PC12 Cells by Suppression of Oxidative Stress-Induced Apoptosis through Regulation of PI3K/Akt Signal Pathway.

Zanthoxylum bungeanum pericarp is a commonly used herbal medicine in China with effects of anti-inflammatory and analgesic, improving learning and memory ability, while hydroxy-α-sanshool (HAS) is the most important active ingredient of Z. bungeanum pericarps. The purpose of this study was to investigate the neuroprotective effect of HAS and its related possible mechanisms using a H2O2-stimulated PC12 cell model. CCK-8 assay results showed that HAS had a significant protective effect on H2O2-stimulated PC12 cells without obvious cytotoxicity on normal PC12 cells. Flow cytometry and fluorescence microscope (DAPI staining and DCFH-DA staining) indicated that HAS could reduce the H2O2-induced apoptosis in PC12 cells via reduction of intracellular ROS and increase of mitochondrial membrane potential (MMP). Subsequently, results of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) determination suggested that HAS could increase the enzyme activities of SOD, CAT, and GSH-Px whereas it could decrease the MDA contents in H2O2-stimulated PC12 cells. Furthermore, the western blotting assays showed that HAS could upregulate the expressions of p-PI3k, Akt, p-Akt, and Bcl-2, while it could downregulate the expressions of cleaved caspase-3 and Bax in H2O2-stimulated PC12 cells. Collectively, it could be concluded according to our results that HAS possesses protective potentials on H2O2-stimulated PC12 cells through suppression of oxidative stress-induced apoptosis via regulation of PI3K/Akt signal pathway.

Piperine protects LPS-induced mastitis by inhibiting inflammatory response.

Mastitis, inflammation in the breast, affects breastfeedingwomenin the postpartumperiod. In the present study, we investigated the protective effects of piperine against mastitis using a mouse mastitis model. LPS-induced mastitis was established by injecting LPS into the canals of the mammary gland. Piperine was given intraperitoneally 1 h before and 12 h after LPS treatment. The results showed that the LPS-induced mammary histopathological changes and MPO activity were attenuated by piperine. LPS-induced inflammatory cytokines TNF-α andIL-1ß were also inhibited by piperine. Furthermore, LPS-induced NF-κB activation was suppressed by the treatment with piperine. In addition, we found piperine dose-dependently increased the expression of PPARγ. All of these results suggested that piperine had protective effects against LPS-induced mastitis and that the mechanism may be mediated through the activation of PPARγ.

EGFR Targeted Paclitaxel and Piperine Co-loaded Liposomes for the Treatment of Triple Negative Breast Cancer.

Triple-negative breast (TNBC) cancer that is upregulated with epidermal growth factor receptor (EGFR), and devoid of both the hormonal receptors and epidermal growth factor receptor 2 (HER 2), has led to a concept of treating TNBC with EGFR-targeted therapeutics. The combination of paclitaxel (PTX) and piperine (PIP) may improve the bioavailability of paclitaxel for cancer therapy. TPGS (vit E-PEG 1000-succinate)-coated liposomes were prepared with PTX alone or in combination with PIP, and either with (targeted) or without (non-targeted) cetuximab (CTX) conjugation. The Bradford assay indicated that 75% of CTX has been conjugated on the liposomes. The size and percent encapsulation of PTX&PIP co-loaded liposomes were found to be in the range of 204 to 218 nm and 31-73%, respectively. The drug release rate was found to be higher at pH 5.5 in comparison with release at pH 6.4 and pH 7.4. Cellular uptake and toxicity studies on MDA-MB-231 cells showed that PTX&PIP co-loaded targeted liposomes have demonstrated superior uptake and cytotoxicity than their non-targeted counterparts. The IC50 values of both of the liposomal formulations were found to be significantly higher than PTX control. Indeed, combining PIP with PTX control has improved the cytotoxicity of PTX control, which proved the synergistic anticancer effect of PIP. Lyophilized liposomes showed an excellent stability profile with the size range between 189 and 210 nm. Plasma stability study revealed a slight increase in the particle size due to the adsorption of plasma proteins on the surface of liposomes. The long-term stability study also indicated that liposomes were stable at 4°C.

Piperine Ameliorates Trimellitic Anhydride-Induced Atopic Dermatitis-Like Symptoms by Suppressing Th2-Mediated Immune Responses via Inhibition of STAT6 Phosphorylation.

Atopic dermatitis (AD) is a common inflammatory skin disease predominately related to Type 2 helper T (Th2) immune responses. In this study, we investigated whether piperine is able to improve AD symptoms using a trimellitic anhydride (TMA)-induced AD-like mouse model. Topical treatment with piperine reduced ear swelling (ear thickness and epidermal thickness) induced by TMA exposure. Furthermore, piperine inhibited pro-inflammatory cytokines such as TNF-α and IL-1ß in mouse ears, compared with the TMA-induced AD group. In measuring allergic immune responses in draining lymph nodes (dLNs), we found that IL-4 secretion, GATA3 mRNA level, and STAT6 phosphorylation were suppressed by piperine treatment. In an ex vivo study, piperine also inhibited the phosphorylation of STAT6 on the CD4+ T cells isolated from splenocytes of BALB/c mice, and piperine suppressed IL-4-induced CCL26 mRNA expression and STAT6 phosphorylation in human keratinocytes resulting in the inhibition of infiltration of CCR3+ cells into inflammatory lesions. These results demonstrate that piperine could ameliorate AD symptoms through suppression of Th2-mediated immune responses, including the STAT6/GATA3/IL-4 signaling pathway. Therefore, we suggest that piperine is an excellent candidate as an inhibitor of STAT6 and may help to improve AD symptoms.

Antiproliferative potential of piperine and curcumin in drug-resistant human leukemia cancer cells are mediated via autophagy and apoptosis induction, S-phase cell cycle arrest and inhibition of cell invasion and migration.

PURPOSE: Leukemia causes annually a significant number of deaths. The main objective of this study was to investigate the anticancer properties of piperine and curcumin against HL60 leukemia cells and to elucidate the underlying mechanism. METHODS: Antiproliferative effects were assessed by WST-1 cell viability assay. Cell apoptotic effects were studied by DAPI staining assay. Annexin V/propidium iodide (PI) assay was used to assess apoptosis. Electron microscopy was used for detection of autophagy and flow cytometry for cell cycle analysis, while transwell migration assay was used to study the effects on cell migration and invasion. Protein expression was estimated by western blot. RESULTS: The results showed that both piperine and curcumin inhibited significantly the growth of the HL60 cells and exhibited an IC50 of 25 and 30 µM respectively. Further, it was observed that the anticancer effects of piperine and curcumin were due to the induction of mitochondrial-mediated apoptosis which was also associated with enhancement of the Bax expression. Transmission electron microscopy also showed that both curcumin and piperine induced autophagy in the HL-60 leukemia cells. Flow cytometry showed that piperine and curcumin also caused arrest of the HL-60 cells at the S-phase of the cell cycle. Finally wound healing and transwell assays showed that piperine and curcumin suppressed the migration and invasive potential of the HL60 cells. CONCLUSIONS: The present study reveals that piperine and curcumin exhibit significant antitumor activity in human leukemia HL60 cells via multiple mechanisms and may prove promising in the development of systemic therapy for leukemia.

Effects of curcuminoids on inflammatory status in patients with non-alcoholic fatty liver disease: A randomized controlled trial.

BACKGROUND: Nonalcoholic fatty liver diseases (NAFLD) is a highly prevalent disease that is closely associated with several cardiometabolic complications. The potential anti-inflammatory role of curcuminoids that have already been reported to reduce hepatic steatosis, in patients with NAFLD was explored in this study. METHODS: This double-blind, randomized placebo-controlled trial was conducted for a period of 8 weeks in patients with NAFLD. Subjects (n = 55) were randomly allocated to receive either curcuminoids or placebo. The curcuminoids group received one capsule containing 500 mg curcuminoids (plus 5 mg piperine to increase intestinal absorption) per day for 8 weeks and the control group received matched placebo capsules for the same period. Liver ultrasonography was performed to assess the severity of hepatic steatosis at baseline and the study end. Serum levels of cytokines including interleukin-1α, interleukin-1ß, interleukin-2, interleukin-4, interleukin-6, interleukin-8, interleukin-10, tumor necrosis factor-α, monocyte chemoattractant protein-1, interferon γ, vascular endothelial growth factor and epidermal growth factor were measured before and after the intervention. RESULTS: The two groups were comparable in demographic features at baseline. The results showed that supplementation with curcuminoids could decrease weight compared to the placebo group (p = 0.016) in patients with NAFLD. Curcuminoids supplementation improved the severity of NAFLD according to the ultrasound results (p = 0.002). Moreover, serum concentrations of TNF-α (p = 0.024), MCP-1 (p = 0.008) and EGF (p = 0.0001) were improved by curcuminoids in NAFLD patients. CONCLUSIONS: The results of our study showed that curcumin supplementation can improve serum levels of inflammatory cytokines in subjects with NAFLD and this might be at least partly responsible for the anti-steatotic effects of curcuminoids.