Immunotoxicological effects of piperine in mice

Piperine and Its Metabolite's Pharmacology in Neurodegenerative and Neurological Diseases

Piperine (PIP) is an active alkaloid of black and long peppers. An increasing amount of evidence is suggesting that PIP and its metabolite's could be a potential therapeutic to intervene different disease conditions including chronic inflammation, cardiac and hepatic diseases, neurodegenerative diseases, and cancer. In addition, the omnipresence of PIP in food and beverages made this compound an important investigational material. It has now become essential to understand PIP pharmacology and toxicology to determine its merits and demerits, especially its effect on the central nervous system (CNS). Although several earlier reports documented that PIP has poor pharmacokinetic properties, such as absorption, bioavailability, and blood-brain barrier permeability. However, its interaction with metabolic enzyme cytochrome P450 superfamily and competitive hydrophobic interaction at Monoamine oxide B (MAO-B) active site have made PIP both a xenobiotics bioenhancer and a potential MAO-B inhibitor. Moreover, recent advancements in pharmaceutical technology have overcome several of PIP's limitations, including bioavailability and blood-brain barrier permeability, even at low doses. Contrarily, the structure activity relationship (SAR) study of PIP suggesting that its several metabolites are reactive and plausibly responsible for acute toxicity or have pharmacological potentiality. Considering the importance of PIP and its metabolites as an emerging drug target, this study aims to combine the current knowledge of PIP pharmacology and biochemistry with neurodegenerative and neurological disease therapy.

Neuroprotective Effects of Black Pepper and Its Bioactive Compounds in Age-Related Neurological Disorders

Age-related neurological disorders (ANDs), including neurodegenerative diseases, are multifactorial disorders whose risk increases with age. The main pathological hallmarks of ANDs include behavioral changes, excessive oxidative stress, progressive functional declines, impaired mitochondrial function, protein misfolding, neuroinflammation, and neuronal cell death. Recently, efforts have been made to overcome ANDs because of their increased age-dependent prevalence. Black pepper, the fruit of Piper nigrum L. in the family Piperaceae, is an important food spice that has long been used in traditional medicine to treat various human diseases. Consumption of black pepper and black pepper-enriched products is associated with numerous health benefits due to its antioxidant, antidiabetic, anti-obesity, antihypertensive, anti-inflammatory, anticancer, hepatoprotective, and neuroprotective properties. This review shows that black pepper's major bioactive neuroprotective compounds, such as piperine, effectively prevent AND symptoms and pathological conditions by modulating cell survival signaling and death. Relevant molecular mechanisms are also discussed. In addition, we highlight how recently developed novel nanodelivery systems are vital for improving the efficacy, solubility, bioavailability, and neuroprotective properties of black pepper (and thus piperine) in different experimental AND models, including clinical trials. This extensive review shows that black pepper and its active ingredients have therapeutic potential for ANDs.

Piperine for treating breast cancer: A review of molecular mechanisms, combination with anticancer drugs, and nanosystems

Piperine (PIP) is an alkaloid found primarily in Piper longum, and this natural compound has been shown to exert effects on proliferation and survival against various types of cancer. In particular, PIP has potent inhibitory effects on breast cancer (BC), the most prevalent type of cancer in women worldwide. PIP targets numerous signaling pathways associated with the therapy of BC cells through the following mechanisms: (a) induction of arrest of the cell cycle and apoptosis; (b) alteration of the signaling protein expression; (c) reduction in transcription factors; and (d) inhibition of tumor growth. BC cells have the ability to resist conventional drugs, so one of the strategies is the combination of PIP with other phytochemicals such as paclitaxel, thymoquinone, hesperidin, bee venom, tamoxifen, mitoxantrone, piperlongumin, and curcumin. Nanotechnology-based drug encapsulation systems are currently used to enhance the release of PIP. This includes polymer nanoparticles, carbon nanotubes, and liposomes. In the present review, the chemistry and bioavailability of PIP, its molecular targets in BC, and nanotechnological strategies are discussed. Future research directions are also discussed to further understand this promising natural product.

Piperine: Chemical, biological and nanotechnological applications

Piperine (PIP) is an alkaloid present in several species of piper, mainly Piper nigrum Linn. and P. longum, among other species. The present article provides a comprehensive review of PIP research in the last years concerning its chemical properties, synthesis, absorption, metabolism, bioavailability and toxicity. The reviewed PIP literature has shown many pharmacological properties, such as antidiabetic, antidiarrheal, antioxidant, antibacterial, and anti-parasitic activity of PIP. However, its low solubility and absorption make its application challenging. This review also includes advances in the development of nanosystems containing PIP, including liposomes, micelles, metal nanoparticles, nanofibers, polymeric nanoparticles, and solid-lipid nanoparticles. Finally, we discuss different in vitro and in vivo studies to evaluate the biological activity of this drug, as well as some methods for the synthesis of nanosystems and their physical characteristics.

Determination and risk characterisation of bio-active piperine in black pepper and selected food containing black pepper consumed in Korea

Piperine is a bio-active compound found in pepper, including Piper nigrum L. and P. longum L. It has a strong, pungent flavour and several pharmacologic benefits. However, the risks of piperine have not yet been characterized. In this study, piperine in black pepper and some selected foods was determined to characterise the risk of exposure to piperine. Piperine in black pepper, curry and noodle was analysed by high-performance liquid chromatography-ultraviolet detection, which was validated through the measurement of performance parameters. The mean concentrations of piperine in black pepper, powdered curry, retorted curry, instant noodle and cup noodle were 4,418, 28, 3.4, 4.3 and 4.2 mg/100 g, respectively. The estimated dietary exposure to piperine was 123.66 μg/kg body weight/day, and the margin of exposure calculated by the no-observed-adverse-effect level of piperine, was 162. The piperine from food does not cause an adverse health effect to the public in Korea.

Comparing the Effect of Piperine and Ilepcimide on the Pharmacokinetics of Curcumin in SD Rats

The poor bioavailability and rapid metabolism of curcumin (CUR) restrict its clinical application. Piperine (PIP), which was extracted from natural compounds, can increase the plasma concentration of curcumin in humanidad. As an artificial synthetic piperine analog, silepcimide (ILE) has significant advantages because of the low price and simple synthesis process. In this study, a simple and rapid HPLC-UV method was developed for determination of the plasma concentration of CUR, PIP,ILE and dihydrocurcumin (DHC, a metabolite of CUR) simultaneously. Meanwhile, the effects of PIP and ILE on the plasma concentration and pharmacokinetics of DHC in SD rats was studied to explore whether ILE could serve as a CUR bioavailability enhancer. The metabolic pathway of CUR was studied by comparing the differences of CUR plasma concentration between intravenous injection and oral administration over the same time period, and reacting with small intestine homogenate without microbes of SD rats. The results of drug-time curve showed that combined administration of ILE and CUR had significant effect on plasma concentrations of DHC. Repeated administration of PIP or ILE could significantly increase the plasma concentration of DHC. Plasma CUR could be detected in the samples of from intravenous injection of CUR rats, whereas, it couldn't be detected in the plasma sample form oral administration rats. CUR incubated with intestinal homogenate without intestinal bacteria could not be transformed into DHC. In conclusion, our results show that ILE can improve the bioavailability of CUR. Additionally, it was inferred that most of the CUR was reduced to DHC by NADPH when it was absorbed from gastrointestinal tract, and our results demonstrated that this pathway might be mediated by gastrointestinal microorganisms.

Overview of the Anticancer Potential of the "King of Spices" Piper nigrum and Its Main Constituent Piperine

The main limits of current anticancer therapy are relapses, chemoresistance, and toxic effects resulting from its poor selectivity towards cancer cells that severely impair a patient's quality of life. Therefore, the discovery of new anticancer drugs remains an urgent challenge. Natural products represent an excellent opportunity due to their ability to target heterogenous populations of cancer cells and regulate several key pathways involved in cancer development, and their favorable toxicological profile. Piper nigrum is one of the most popular spices in the world, with growing fame as a source of bioactive molecules with pharmacological properties. The present review aims to provide a comprehensive overview of the anticancer potential of Piper nigrum and its major active constituents-not limited to the well-known piperine-whose undeniable anticancer properties have been reported for different cancer cell lines and animal models. Moreover, the chemosensitizing effects of Piper nigrum in association with traditional anticancer drugs are depicted and its toxicological profile is outlined. Despite the promising results, human studies are missing, which are crucial for supporting the efficacy and safety of Piper nigrum and its single components in cancer patients.

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.

Iron and Physical Activity: Bioavailability Enhancers, Properties of Black Pepper (Bioperine®) and Potential Applications

Black pepper (Piper nigrum L.) has been employed in medicine (epilepsy, headaches, and diabetes), where its effects are mainly attributed to a nitrogen alkaloid called piperidine (1-(1-[1,3-benzodioxol-5-yl]-1-oxo-2,4 pentenyl) piperidine). Piperine co-administered with vitamins and minerals has improved its absorption. Therefore, this study aimed to describe the impact of the joint administration of iron (Fe) plus black pepper in physically active healthy individuals. Fe is a micronutrient that aids athletic performance by influencing the physiological functions involved in endurance sports by improving the transport, storage, and utilization of oxygen. Consequently, athletes have risk factors for Fe depletion, Fe deficiency, and eventually, anemia, mainly from mechanical hemolysis, gastrointestinal disturbances, and loss of Fe through excessive sweating. Declines in Fe stores have been reported to negatively alter physical capacities such as aerobic capacity, strength, and skeletal muscle recovery in elite athletes. Thus, there is a need to maintain Fe storage, even if Fe intake meets the recommended daily allowance (RDA), and Fe supplementation may be justified in physically active individuals, in states of Fe deficiency, with or without anemia. Females, in particular, should monitor their Fe hematological profile. The recommended oral Fe supplements are ferrous or ferric salts, sulfate, fumarate, and gluconate. These preparations constitute the first line of treatment; however, the high doses administered have gastrointestinal side effects that reduce tolerance and adherence to treatment. Thus, a strategy to counteract these adverse effects is to improve the bioavailability of Fe. Therefore, piperine may benefit the absorption of Fe through its bioavailability enhancement properties. Three research studies of Fe associated with black pepper have reported improvements in parameters related to the metabolism of Fe, without adverse effects. Although more research is needed, this could represent an advance in oral Fe supplementation for physically active individuals.

Piperine: Old Spice and New Nutraceutical?

BACKGROUND

Many of the activities associated with pepper fruits have been attributed to piperine, the most active compound present in these spices.

OBJECTIVE

This paper aims to provide an overview of the known properties of piperine, i.e. piperine's chemistry, its physiological activity, documented interactions as a bioenhancer and reported data concerning its toxicity, antioxidant properties and anticancer activity.

DISCUSSION

It is known that piperine possesses several properties. In its interaction with other drugs, it can act as a bioavailability enhancer; this effect is also manifested in combination with other nutraceuticals, e.g. with curcumin, i.e. piperine can modify curcumin's antioxidant, anti-inflammatory, antimicrobial and anticancer effects. Piperine displays significant immunomodulating, antioxidant, chemopreventive and anticancer activity; these effects have been shown to be dose-dependent and tissue-specific. However, the main limitation associated with piperine seems to be its low bioavailability, a disadvantage that innovative formulations are overcoming.

CONCLUSION

It is predicted that an increasing number of studies will focus on piperine, especially those directed towards unraveling its properties at molecular level. The current knowledge about the action of piperine will form a foundation for ways to improve piperine's bioavailability e.g. exploitation of different carrier systems. The therapeutical applications of this compound will be clarified, and piperine will be recognized as an important nutraceutical.

Delivery of Docetaxel to Brain Employing Piperine-Tagged PLGA-Aspartic Acid Polymeric Micelles: Improved Cytotoxic and Pharmacokinetic Profiles

In this study, poly-(lactic-co-glycolic) acid (PLGA) was conjugated with aspartic acid and was characterized by nuclear magnetic resonance and Fourier transform infrared spectroscopy. Docetaxel-loaded polymeric micelles were prepared, and piperine was tagged. The neuroblastoma cytotoxicity studies revealed a substantially higher cytotoxic potential of the developed system to that of plain docetaxel, which was further corroborated by cellular uptake employing confocal laser scanning microscopy. The hemocompatible system was able to enhance the pharmacokinetic profile in terms of 6.5-fold increment in bioavailability followed by a 3.5 times increase in the retention time in comparison with the plain drug. The single-point brain bioavailability of docetaxel was amplified by 3.3-folds, signifying a better uptake and distribution to brain employing these carriers. The findings are unique as the physically adsorbed piperine was released before the DTX, increasing the propensity of curbing the CYP3A4 enzyme, which plays a vital role in the degradation of docetaxel. Meanwhile, piperine might have compromised the P-gp efflux mechanism, which can be ascribed to the enhanced retention of the drug at the target site. The elevated target site concentrations and extended residence by a biocompatible nanocarrier supplemented with co-delivery of piperine inherit immense promises to deliver this BCS class IV drug more safely and effectively.

Th1-Biased Immunomodulation and In Vivo Antitumor Effect of a Novel Piperine Analogue

Natural products have an important role as prototypes in the synthesis of new anticancer drugs. Piperine is an alkaloid amide with antitumor activity and significant toxicity. Then, the N-(p-nitrophenyl)acetamide piperinoate (HE-02) was synthesized, and tested for toxicological and antitumor effects. The toxicity was evaluated in vitro (on RAW 264.7 cells and mice erythrocytes) and in vivo (acute toxicity in mice). The Ehrlich ascites carcinoma model was used to evaluate the antitumor activity of HE-02 (6.25, 12.5 or 25 mg/kg, intraperitoneally, i.p.), as well as toxicity. HE-02 induced only 5.01% of hemolysis, and reduced the viability of RAW 264.7 cells by 49.75% at 1000 µg/mL. LD50 (lethal dose 50%) was estimated at around 2000 mg/kg (i.p.). HE-02 reduced Ehrlich tumor cell viability and peritumoral microvessels density. There was an increase of Th1 helper T lymphocytes cytokine profile levels (IL-1β, TNF-α, IL-12) and a decrease of Th2 cytokine profile (IL-4, IL-10). Moreover, an increase was observed on reactive oxygen species and nitric oxide production. Weak in vivo toxicological effects were recorded. Our data provide evidence that the piperine analogue HE-02 present low toxicity, and its antitumor effect involves modulation of immune system to a cytotoxic Th1 profile.

An integrated strategy for rapid discovery and identification of the sequential piperine metabolites in rats using ultra high-performance liquid chromatography/high resolution mass spectrometery

Piperine, one of the major bioactive constituents isolated from natural flavorings and medicinal-culinary herbs, possesses various biological activities. In the present study, an integrated strategy based on ultra high-performance liquid chromatography/high resolution mass spectrometry was established to reveal piperine metabolism in rats. First of all, post-acquisition data-mining methods, including high resolution extracted ion chromatograms (HREICs) and multiple mass defect filtering (MMDF), were used to screen piperine metabolite candidates in a full-scan HRMS¹ level. Then, parent ion list-dynamic exclusion coupled with data-dependent data-acquisition method was utilized to acquire MSⁿ datasets. In addition, the established reverse molecular assembly (RMA) approach based on paired diagnostic product ions (pDPIs) coupled with neutral loss fragments (NLFs) was used to ascertain and identify the major-to-trace piperine metabolites efficiently. And then, the calculated ClogP values were utilized to distinguish the positional isomers. As a result, a total of 148 piperine metabolites were detected and characterized tentatively. The results demonstrated that piperine mainly underwent hydrogenation, dehydrogenation, hydroxylation, glucuronide conjugation, sulfate conjugation, ring-cleavage, and their composite reactions. Our results not only provided novel and useful data to better understand the safety, toxicity and efficacy of this potential therapeutic agent, but also indicated that the proposed strategy was reliable for a rapid discovery and identification drug-related constituents in vivo.

Piperine and Its Various Physicochemical and Biological Aspects: A Review

Piper nigrumL. is examined as the king of species worldwide by virtue of its principle piperine. In Ayurveda, since from the ancient times, it is known as “Yogvahi”. It is one of the important alkaloids of Pepper fruits (Family Piperaceae) and has been found to have numerous medicinal properties such as antioxidant, antiplatelet, anti-inflammatory, antihypertensive, hepatoprotective, antithyroid, antitumor, antiasthmatic activity and also have significant role as fertility enhancer. The present review discusses the biosynthetic pathway, extraction process, chemistry and various analytical methods of piperine. It also describes the structural modification of piperine and its various effects on biological system. The utility of piperine as a bioenhancer for certain antibacterial- antibiotics and a potent inhibitor of drug metabolism are also discussed. Thus, review provides knowledgeable erudition on the piperine which paves way for further work.

Antigenotoxic Effect of Piperine in Broiler Chickens Intoxicated with Aflatoxin B1

Piperine is an abundant amide extracted from black pepper seeds which has been shown to have protective effects against cytotoxic and genotoxic carcinogenesis induced by certain chemical carcinogens and aflatoxin B₁ (AFB₁) in vitro. The aim of this work was to study, in vivo, the antigenotoxic potential of feed-added piperine on broiler chickens experimentally intoxicated with AFB₁, using micronucleus and comet assays. The antigenotoxicity assessment of 9-day-old chicks was performed on a total of 60 chickens divided into four groups of 15 broilers each: (C) control, (P) 60 mg·piperine kg-1 feed, (A) 0.5 mg·AFB₁·kg-1 body weight, (daily by oral route), and (P + A) co-treatment with piperine and AFB₁. The experiment was conducted for 26 days. Chicks intoxicated with AFB₁ showed significant genotoxic effects in the first 24 h post intoxication, and the effects remained in the other periods analyzed (48, 72, and 96 h and 26 days of treatment). The DNA damage in peripheral blood cells, the number of erythrocytes with micronuclei, and polychromatic-to-normochromatic erythrocyte ratio were significantly reduced or absent in the piperine/AFB₁ group. No significant differences were observed between the group piperine/AFB₁ and the control and piperine-alone groups. The addition 60 mg·kg-1 of piperine to the diet of the broiler chicks was safe, promoting beneficial effects in poultry health with respect to the toxic effects 0.5 mg·AFB₁·kg-1 body weight.

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.

Piper nigrum and piperine: an update

Black pepper (Piper nigrum L.) is a very widely used spice, known for its pungent constituent piperine. However, in addition to its culinary uses, pepper has important medicinal and preservative properties, and, more recently, piperine has been shown to have fundamental effects on p-glycoprotein and many enzyme systems, leading to biotransformative effects including chemoprevention, detoxification, and enhancement of the absorption and bioavailability of herbal and conventional drugs. Based on modern cell, animal, and human studies, piperine has been found to have immunomodulatory, anti-oxidant, anti-asthmatic, anti-carcinogenic, anti-inflammatory, anti-ulcer, and anti-amoebic properties. In this review, the chemical constituents, biological activities, effects of processing, and future potential of black pepper and piperine have been discussed thoroughly.

A comprehensive review on pharmacotherapeutics of herbal bioenhancers

In India, Ayurveda has made a major contribution to the drug discovery process with new means of identifying active compounds. Recent advancement in bioavailability enhancement of drugs by compounds of herbal origin has produced a revolutionary shift in the way of therapeutics. Thus, bibliographic investigation was carried out by analyzing classical text books and peer-reviewed papers, consulting worldwide-accepted scientific databases from last 30 years. Herbal bioenhancers have been shown to enhance bioavailability and bioefficacy of different classes of drugs, such as antibiotics, antituberculosis, antiviral, antifungal, and anticancerous drugs at low doses. They have also improved oral absorption of nutraceuticals like vitamins, minerals, amino acids, and certain herbal compounds. Their mechanism of action is mainly through absorption process, drug metabolism, and action on drug target. This paper clearly indicates that scientific researchers and pharmaceutical industries have to give emphasis on experimental studies to find out novel active principles from such a vast array of unexploited plants having a role as a bioavailability and bioefficacy enhancer. Also, the mechanisms of action by which bioenhancer compounds exert bioenhancing effects remain to be explored.

Alkaloids isolated from natural herbs as the anticancer agents

Alkaloids are important chemical compounds that serve as a rich reservoir for drug discovery. Several alkaloids isolated from natural herbs exhibit antiproliferation and antimetastasis effects on various types of cancers both in vitro and in vivo. Alkaloids, such as camptothecin and vinblastine, have already been successfully developed into anticancer drugs. This paper focuses on the naturally derived alkaloids with prospective anticancer properties, such as berberine, evodiamine, matrine, piperine, sanguinarine, and tetrandrine, and summarizes the mechanisms of action of these compounds. Based on the information in the literature that is summarized in this paper, the use of alkaloids as anticancer agents is very promising, but more research and clinical trials are necessary before final recommendations on specific alkaloids can be made.

Oral administration of piperine for the control of aflatoxin intoxication in rats

Aflatoxins are mycotoxins that have important toxic effects on human and animal health, even if consumed at low doses. The oral administration of piperine (1.12 mg/kg) during 23 days in rats seemingly interfered with the toxicity of aflatoxins, decreasing hepatic injuries and the leukocyte depletion in experimentally intoxicated animals.

Anti-inflammatory and antiarthritic effects of piperine in human interleukin 1beta-stimulated fibroblast-like synoviocytes and in rat arthritis models

Introduction

The objective of this study was to determine the anti-inflammatory, nociceptive, and antiarthritic effects of piperine, the active phenolic component in black pepper extract.

Methods

The in vitro anti-inflammatory activity of piperine was tested on interleukin 1β (IL1β)-stimulated fibroblast-like synoviocytes derived form patients with rheumatoid arthritis. The levels of IL6, matrix metalloproteinase (MMPs), cyclo-oxygenase 2 (COX-2), and prostaglandin E2 (PGE₂) were investigated by ELISA and RT-PCR analysis. The analgesic and antiarthritic activities of piperine were investigated on rat models of carrageenan-induced acute paw pain and arthritis. The former were evaluated with a paw pressure test, and the latter by measuring the squeaking score, paw volume, and weight distribution ratio. Piperine was administrated orally to rats at 20 and 100 mg/kg/day for 8 days.

Results

Piperine inhibited the expression of IL6 and MMP13 and reduced the production of PGE₂ in a dose dependant manner at concentrations of 10 to 100 μg/ml. In particular, the production of PGE₂ was significantly inhibited even at 10 μg/ml of piperine. Piperine inhibited the migration of activator protein 1 (AP-1), but not nuclear factor (NF)κB, into the nucleus in IL1β-treated synoviocytes. In rats, piperine significantly reduced nociceptive and arthritic symptoms at days 8 and 4, respectively. Histological staining showed that piperine significantly reduced the inflammatory area in the ankle joints.

Conclusions

These results suggest that piperine has anti-inflammatory, antinociceptive, and antiarthritic effects in an arthritis animal model. Thus, piperine should be further studied with regard to use either as a pharmaceutical or as a dietary supplement for the treatment of arthritis.

Safety evaluation of Trikatu, a generic Ayurvedic medicine in Charles Foster rats

Chemical characterization and acute and sub-acute toxicity study of Trikatu, a generic herbal formulation of Indian system of medicine, was carried out in Charles Foster (CF) rats for safety profiling. In acute toxicity experiment, Trikatu at 2,000 mg/kg body weight once orally was well tolerated by the experimental animals (both male and female) and no changes were observed in mortality, morbidity, gross pathology, gain in weight, vital organ weight, hematological (total white blood cells (WBC) and red blood cells (RBC) count), biochemical parameters such as serum creatinine, serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), serum lipid profile and tissue biochemical parameters such as reduced glutathione and malonaldehyde content as oxidative stress markers. In sub-acute experiment, Trikatu was administered at 5, 50 and 300 mg/kg body weight once daily for 28 days in female CF rats, and non-significant changes were found in most of the parameters studied such as acute experiment except significant increase in low density lipoprotein (LDL) cholesterol level at 50 and 300 mg/kg body weight, decrease in high density lipoprotein (HDL) cholesterol level at 300 mg/kg body weight, increase in SGPT activity at 50 mg/kg body weight and decrease in WBC count at 300 mg/kg body weight on 28(th) day post treatment.

In vitro and in vivo antitumor effect of 5-FU combined with piplartine and piperine

It has been reported that piplartine and piperine, alkaloid/amide compounds from Piper species, show antitumor activities. In the present paper, the effects of the combination of 5-fluorouracil (5-FU) with piplartine or piperine was determined using in vitro and in vivo experimental models. Hematological and biochemical analyses, as well as histopathological and morphological analyses of the tumor and the organs, including liver, spleen and kidney, were performed in order to evaluate the toxicological aspects associated with different treatments. The incubation of tumor cell lines with 5-FU in the presence of piplartine or piperine produced an increase in growth inhibition, as observed by lower IC50 values for 5-FU. These effects were also observed in vivo, where the combination with piplartine but not piperine with 5-FU led to a higher tumor growth inhibition. The results indicated that either piplartine- or 5-FU-treated animals showed a low inhibition rate when they were used individually at low doses of 28.67% and 47.71%, respectively, but when they were combined at the same dose, the inhibition rate increased significantly to 68.04%. The histopathological analysis showed that the livers and the kidneys of treated animals were only slightly and reversibly affected. Neither the enzymatic activity of transaminases nor the urea levels were significantly modified when compared with the control group. Hematological analysis showed leukopenia after 5-FU treatment, which was reversed by the combined use of piplartine and piperine. These findings indicate that piplartine may enhance the therapeutic effectiveness of chemotherapeutic drugs, and moreover, this combination could improve immunocompetence hampered by 5-FU.

Black pepper and its pungent principle-piperine: a review of diverse physiological effects

Black pepper (Piper nigrum) is one of the most widely used among spices. It is valued for its distinct biting quality attributed to the alkaloid, piperine. Black pepper is used not only in human dietaries but also for a variety of other purposes such as medicinal, as a preservative, and in perfumery. Many physiological effects of black pepper, its extracts, or its major active principle, piperine, have been reported in recent decades. Dietary piperine, by favorably stimulating the digestive enzymes of pancreas, enhances the digestive capacity and significantly reduces the gastrointestinal food transit time. Piperine has been demonstrated in in vitro studies to protect against oxidative damage by inhibiting or quenching free radicals and reactive oxygen species. Black pepper or piperine treatment has also been evidenced to lower lipid peroxidation in vivo and beneficially influence cellular thiol status, antioxidant molecules and antioxidant enzymes in a number of experimental situations of oxidative stress. The most far-reaching attribute of piperine has been its inhibitory influence on enzymatic drug biotransforming reactions in the liver. It strongly inhibits hepatic and intestinal aryl hydrocarbon hydroxylase and UDP-glucuronyl transferase. Piperine has been documented to enhance the bioavailability of a number of therapeutic drugs as well as phytochemicals by this very property. Piperine's bioavailability enhancing property is also partly attributed to increased absorption as a result of its effect on the ultrastructure of intestinal brush border. Although initially there were a few controversial reports regarding its safety as a food additive, such evidence has been questionable, and later studies have established the safety of black pepper or its active principle, piperine, in several animal studies. Piperine, while it is non-genotoxic, has in fact been found to possess anti-mutagenic and anti-tumor influences.

In vivo growth-inhibition of Sarcoma 180 by piplartine and piperine, two alkaloid amides from Piper

Piplartine {5,6-dihydro-1-[1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)pyridinone} and piperine {1-5-(1,3)-benzodioxol-5-yl)-1-oxo-2,4-pentadienyl]piperidine} are alkaloid amides isolated from Piper. Both have been reported to show cytotoxic activity towards several tumor cell lines. In the present study, the in vivo antitumor activity of these compounds was evaluated in 60 female Swiss mice (N = 10 per group) transplanted with Sarcoma 180. Histopathological and morphological analyses of the tumor and the organs, including liver, spleen, and kidney, were performed in order to evaluate the toxicological aspects of the treatment with these amides. Administration of piplartine or piperine (50 or 100 mg kg(-1) day(-1) intraperitoneally for 7 days starting 1 day after inoculation) inhibited solid tumor development in mice transplanted with Sarcoma 180 cells. The inhibition rates were 28.7 and 52.3% for piplartine and 55.1 and 56.8% for piperine, after 7 days of treatment, at the lower and higher doses, respectively. The antitumor activity of piplartine was related to inhibition of the tumor proliferation rate, as observed by reduction of Ki67 staining, a nuclear antigen associated with G1, S, G2, and M cell cycle phases, in tumors from treated animals. However, piperine did not inhibit cell proliferation as observed in Ki67 immunohistochemical analysis. Histopathological analysis of liver and kidney showed that both organs were reversibly affected by piplartine and piperine treatment, but in a different way. Piperine was more toxic to the liver, leading to ballooning degeneration of hepatocytes, accompanied by microvesicular steatosis in some areas, than piplartine which, in turn, was more toxic to the kidney, leading to discrete hydropic changes of the proximal tubular and glomerular epithelium and tubular hemorrhage in treated animals.

Brahmi rasayana improves learning and memory in mice

Cure of cognitive disorders such as amnesia, attention deficit and Alzheimer's disease is still a nightmare in the field of medicine. Nootropic agents such as piracetam, aniracetam and choline esterase inhibitors like Donepezil^® are being used to improve memory, mood and behavior, but the resulting side effects associated with these agents have made their use limited. The present study was undertaken to assess the potential of Brahmi rasayana (BR) as a memory enhancer. BR (100 and 200 mg kg⁻¹ p.o.) was administered for eight successive days to both young and aged mice. Elevated plus maze and passive-avoidance paradigm were employed to evaluate learning and memory parameters. Scopolamine (0.4 mg kg⁻¹ i.p.) was used to induce amnesia in mice. The effect of BR on whole brain AChE activity was also assessed. Piracetam (200 mg kg⁻¹ i.p.) was used as a standard nootropic agent. BR significantly improved learning and memory in young mice and reversed the amnesia induced by both scopolamine (0.4 mg kg⁻¹ i.p.) and natural aging. BR significantly decreased whole brain acetyl cholinesterase activity. BR might prove to be a useful memory restorative agent in the treatment of dementia seen in elderly.