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.

Fatty acid amide hydrolase activity in the dorsal periaqueductal gray attenuates neuropathic pain and associated dysautonomia.

The complexity of neuropathic pain and its associated comorbidities, including dysautonomia, make it difficult to treat. Overlap of anatomical regions and pharmacology of sympathosensory systems in the central nervous system (CNS) provide targets for novel treatment strategies. The dorsal periaqueductal gray (dPAG) is an integral component of both the descending pain modulation system and the acute stress response and is critically involved in both analgesia and the regulation of sympathetic activity. Local manipulation of the endocannabinoid signaling system holds great promise to provide analgesia without excessive adverse effects and also influence autonomic output. Inhibition of fatty acid amide hydrolase (FAAH) increases brain concentrations of the endocannabinoid N-arachidonoylethanolamine (AEA) and reduces pain-related behaviors in neuropathic pain models. Neuropathic hyperalgesia and reduced sympathetic tone are associated with increased FAAH activity in the dPAG, which suggests the hypothesis that inhibition of FAAH in the dPAG will normalize pain sensation and autonomic function in neuropathic pain. To test this hypothesis, the effects of systemic or intra-dPAG FAAH inhibition on hyperalgesia and dysautonomia developed after spared nerve injury (SNI) were assessed in male and female rats. Administration of the FAAH inhibitor PF-3845 into the dPAG reduces hyperalgesia behavior and the decrease in sympathetic tone induced by SNI. Prior administration of the CB1 receptor antagonist AM281, attenuated the antihyperalgesic and sympathetic effects of FAAH inhibition. No sex differences were identified. These data support an integrative role for AEA/CB1 receptor signaling in the dPAG contributing to the regulation of both hyperalgesia behavior and altered sympathetic tone in neuropathic pain.

The Role of the Possible Receptors and Intracellular Pathways in Protective Effect of Exogenous Anandamide in Kindling Model of Epilepsy.

In this research, the involvement of CB1 and TRPV1 receptors in the possible protective effects of anandamide were investigated in the kindling model of epilepsy. The basolateral amygdala of the rat brain was chosen to put stimulating electrodes. Semi-rapid kindling was induced by a repetitive sub-threshold stimulation for 5-9 consecutive days. There were seven groups, six of which were kindled and used for drug testing by intracerebroventricular (i.c.v.) microinjection. (i) Sham, (ii) control group received vehicles, (iii) anandamide (AEA; 100 ng/rat), (iv) capsazepine (TRPV1 antagonist; 100 ng/rat), (v) AM251 (CB1 antagonist; 100 ng/rat), (vi) AM251 + anandamide, and (vii) capsazepine + anandamide. The after-discharge duration, seizure duration, and stage five duration were measured in rats. Moreover, the expressions of the extracellular signal-regulated kinase (ERK) and the cAMP responsive element binding (CREB) proteins in the hippocampus were also studied. The anandamide-treated group showed a significant decrease in seizure scores, while no change was shown in seizure scores in the capsazepine- and AM251-treated groups compared with the control group. Co-administrations of either capsazepine + AEA or AM251 + AEA attenuated the protective effect of AEA against seizure. Furthermore, the group received AEA showed a decrease in the expressions of CREB and p-CREB possibly through the activation of the CB1 and TRPV1 receptors. Activation of CB1 and TRPV1 receptors might be involved in AEA anticonvulsant effect in kindling model of epilepsy. This effect could be due to suppression of CREB phosphorylation in hippocampal neurons.

A critical review on the extraction and pharmacotherapeutic activity of piperine.

Black pepper (Piper nigrum L.) is a climbing perennial plant in the Piperaceae family. Pepper has been known since antiquity for its use both as a medicine and a spice. It is particularly valued for its pungency attributed to its principal constituent - piperine. This review summarizes the information on the biological source of piperine, its extraction and isolation strategies, physicochemical properties, and pharmacological activity - analgesic, immunomodulatory, anti-depressive, anti-diarrheal, hepatoprotective, etc. The effect of piperine on biotransformation of co-administered drugs is also presented in this review, along with the mechanisms involved in its bioavailability-enhancing effect. Its important medicinal uses, including anti-hepatotoxic, anti-diarrheal, anti-depressive, analgesic, and immunomodulatory effects, besides many other traditional uses, are compiled. Based on an exhaustive review of literature, it may be concluded that piperine is a very promising alkaloid found in members of the Piperaceae family.

Curcumin induces peripheral antinociception by opioidergic and cannabinoidergic mechanism: Pharmacological evidence.

BACKGROUND: Curcumin is one of the compounds present in plants of the genus Curcuma sp., being very used not only as condiment but also with medicinal purposes. As an analgesic, papers highlight the efficacy of curcumin in the treatment of various types of pain. AIMS: In this study we evaluated the peripheral antinociceptive effect of curcumin and by which mechanisms this effect is induced. MAIN METHODS: The mice paw pressure test was used on animals which had increased pain sensitivity by intraplantar injection of carrageenan. All the drugs were administered in the right hind paw. KEY FINDINGS: Curcumin was administered to the right hind paw animals induced antinociceptive effect. Non -selective antagonist of opioid receptors naloxone reverted the antinociceptive effect induced by curcumin. Selective antagonists for µ, δ and κ opioid receptors clocinnamox, naltrindole and nor- binaltorphimine, respectively, reverted the antinociceptive effect induced by curcumin. Bestatin, enkephalinases inhibitor that degrade peptides opioids, did not change the nociceptive response. Selective antagonists for CB1 and CB2 cannabinoid receptors, AM251 and AM630, respectively, reversed the antinociceptive effect induced by curcumin. The MAFP inhibitor of the enzyme FAAH which breaks down anandamide, JZL184, enzyme inhibitor MAGL which breaks down the 2-AG, as well as the VDM11 anandamide reuptake inhibitor potentiated the antinociceptive effect of curcumin. SIGNIFICANCE: These results suggest that curcumin possibly peripheral antinociception induced by opioid and cannabinoid systems activation and possibly for endocannabinoids and opioids release.

Piperine mitigates behavioral impairments and provides neuroprotection against 3-nitropropinoic acid-induced Huntington disease-like symptoms.

Background: Piperine (PIP) is a powerful anti-oxidant and anti-inflammatory alkaloid which has been widely used in the treatment of various pathological conditions. However, few studies have clearly discussed the protective effects and potential mechanism of PIP in different neurological diseases. The aim of this study was to investigate the neuroprotective effect of PIP against 3-nitropropioninc acid (3-NP) induced neurobehavioral, biochemical and histopathological alterations in animals.Methods: Adult male Wistar rats were randomly divided into three groups. Group 1, the vehicle administered control group, received normal saline (p.o.). Group 2 received 3-NP (20 mg/kg.b.wt., i.p.) for 4 consecutive days. Group 3 received PIP (10 mg/kg.b.wt., p.o.) twice daily for a period of 4 days, 30 min before and 6 h after the 3-NP injection. Upon termination of treatment schedule, behavioral experiments were performed to access the behavioral outcomes. The brain striatal tissue was used for the estimation of monoamine oxidase activity and serotonin level. In addition, astrocytes activation was observed by GFAP immunostaining.Results: Our results showed that 3-NP induced behavioral impairments are attenuated by PIP co-treatment. Next, the extent of neuronal loss and astrocytes activation was reduced in the striatal brain region in PIP treated rats. Finally, it was observed that PIP alleviated the behavioral, biochemical, immunohistochemical and histological alterations.Conclusion: The results of the current study reveal the neuroprotective competency of PIP against Huntington disease like symptoms in rats.

Protective actions of vitamin D, anandamide and melatonin during vascular inflammation: Epigenetic mechanisms involved.

Vascular inflammation is one of the main activating stimuli of cardiovascular disease and its uncontrolled development may worsen the progression and prognosis of these pathologies. Therefore, the search for new therapeutic options to treat this condition is undoubtedly needed. In this regard, it may be better to repurpose endogenous anti-inflammatory compounds already known, in addition to synthesizing new compounds for therapeutic purposes. It is well known that vitamin D, anandamide, and melatonin are promising endogenous substances with powerful and wide-spread anti-inflammatory properties. Currently, the epigenetic mechanisms underlying these effects are often unknown. This review summarizes the potential epigenetic mechanisms by which vitamin D, anandamide, and melatonin attenuate vascular inflammation. This information could contribute to the improvement in the therapeutic management of multiple pathologies associated with blood vessel inflammation, through the pharmacological manipulation of new target sites that until now have not been addressed.

Endocannabinoid Anandamide Attenuates Acute Respiratory Distress Syndrome through Modulation of Microbiome in the Gut-Lung Axis.

Acute respiratory distress syndrome (ARDS) is a serious lung condition characterized by severe hypoxemia leading to limitations of oxygen needed for lung function. In this study, we investigated the effect of anandamide (AEA), an endogenous cannabinoid, on Staphylococcal enterotoxin B (SEB)-mediated ARDS in female mice. Single-cell RNA sequencing data showed that the lung epithelial cells from AEA-treated mice showed increased levels of antimicrobial peptides (AMPs) and tight junction proteins. MiSeq sequencing data on 16S RNA and LEfSe analysis demonstrated that SEB caused significant alterations in the microbiota, with increases in pathogenic bacteria in both the lungs and the gut, while treatment with AEA reversed this effect and induced beneficial bacteria. AEA treatment suppressed inflammation both in the lungs as well as gut-associated mesenteric lymph nodes (MLNs). AEA triggered several bacterial species that produced increased levels of short-chain fatty acids (SCFAs), including butyrate. Furthermore, administration of butyrate alone could attenuate SEB-mediated ARDS. Taken together, our data indicate that AEA treatment attenuates SEB-mediated ARDS by suppressing inflammation and preventing dysbiosis, both in the lungs and the gut, through the induction of AMPs, tight junction proteins, and SCFAs that stabilize the gut-lung microbial axis driving immune homeostasis.

Piperine Improves Experimental Autoimmune Encephalomyelitis (EAE) in Lewis Rats Through its Neuroprotective, Anti-inflammatory, and Antioxidant Effects.

Inflammation, demyelination, glial activation, and oxidative damage are the most pathological hallmarks of multiple sclerosis (MS). Piperine, a main bioactive alkaloid of black pepper, possesses antioxidant, anti-inflammatory, and neuroprotective properties whose therapeutic potential has been less studied in the experimental autoimmune encephalomyelitis (EAE) models. In this study, the efficiency of piperine on progression of EAE model and myelin repair mechanisms was investigated. EAE was induced in female Lewis rats and piperine and its vehicle were daily administrated intraperitoneally from day 8 to 29 post immunization. We found that piperine alleviated neurological deficits and EAE disease progression. Luxol fast blue and H&E staining and immunostaining of lumbar spinal cord cross sections confirmed that piperine significantly reduced the extent of demyelination, inflammation, immune cell infiltration, microglia, and astrocyte activation. Gene expression analysis in lumbar spinal cord showed that piperine treatment decreased the level of pro-inflammatory cytokines (TNF-α, IL-1ß) and iNOS and enhanced IL-10, Nrf2, HO-1, and MBP expressions. Piperine supplementation also enhanced the total antioxidant capacity (FRAP) and reduced the level of oxidative stress marker (MDA) in the CNS of EAE rats. Finally, we found that piperine has anti-apoptotic and neuroprotective effect in EAE through reducing caspase-3 (apoptosis marker) and enhancing BDNF and NeuN expressing cells. This study strongly indicates that piperine has a beneficial effect on the EAE progression and could be considered as a potential therapeutic target for MS treatment. Upcoming clinical trials will provide a deeper understanding of piperine's role for the treatment of the MS.

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.

Development and validation of a rapid high-performance thin-layer chromatographic method for quantification of gallic acid, cinnamic acid, piperine, eugenol, and glycyrrhizin in Divya-Swasari-Vati, an ayurvedic medicine for respiratory ailments.

Divya-Swasari-Vati is a calcium containing polyherbal ayurvedic medicine prescribed for the lung-related ailments observed in the current pandemic of Severe Acute Respiratory Syndrome Coronavirus 2 infections. The formulation is a unique quintessential blend of nine herbs cited in Ayurvedic texts for chronic cough and lung infection. Analytical standardization of herbal medicines is the pressing need of the hour to ascertain the quality compliance. This persuaded us to develop a simple, rapid, and selective high-performance thin-layer chromatographic method for Divya-Swasari-Vati quality standardization. The developed method was validated for the quantification of marker components, gallic acid, cinnamic acid, piperine, eugenol and glycyrrhizin, against reference standards in five different batches of Divya-Swasari-Vati. The analytes were identified by visualization at 254 nm, and by matching their retention factor with authentic standards. The developed method was validated as per the guidelines recommended by the International Council for Harmonization for parameters like, linearity, limit of detection, limit of quantification, accuracy, and precision. Therefore, the developed novel high-performance thin-layer chromatographic process could be employed for rapid standardization of Divya-Swasari-Vati and other related herbal formulation, which would aid in quality manufacturing and product development.

The rise and fall of anandamide: processes that control synthesis, degradation, and storage.

Anandamide is an endocannabinoid derived from arachidonic acid-containing membrane lipids and has numerous biological functions. Its effects are primarily mediated by the cannabinoid receptors CB1 and CB2, and the vanilloid TRPV1 receptor. Anandamide is known to be involved in sleeping and eating patterns as well as pleasure enhancement and pain relief. This manuscript provides a review of anandamide synthesis, degradation, and storage and hence the homeostasis of the anandamide signaling system.

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.

Effectiveness of the piperine-supplemented Curcuma longa L. in metabolic control of patients with type 2 diabetes: a randomised double-blind placebo-controlled clinical trial.

There is robust evidence of using Curcuma longa L. in reducing metabolic levels in people with diabetes. This study analysed the effectiveness of Curcuma longa L. in the metabolic control of patients with type 2 diabetes in Brazil. A randomised double-blind placebo-controlled clinical trial was conducted with 71 participants divided into a Curcuma longa L. group (500 mg/day with piperine 5 mg) and a placebo group, for 120 days. Anthropometric, clinical and biochemical variables were evaluated at baseline, 60 and 120 days after the beginning of the intervention. Paired and independent Student's t-test and chi-square test were used for statistical analysis. The curcuma group presented a significantly decreased glycaemia (p=.013), glycated haemoglobin (p=.015), HOMA index (p=.037) and triglycerides (TGs) (p=.002). The use of piperine-added Curcuma longa L. was effective in the glycaemic and TG control of patients with type 2 diabetes.

Curcumin and Piperine Combination for the Treatment of Patients with Non-alcoholic Fatty Liver Disease: A Double-Blind Randomized Placebo-Controlled Trial.

BACKGROUND: Experimental and clinical studies have revealed that curcumin may be an effective therapy for non-alcoholic fatty liver disease (NAFLD). Hence, the aim of this study was to assess the effect of curcumin plus piperine administration on NAFLD. METHODS: Adults 18-65 years-old diagnosed with NAFLD by liver sonography were randomly allocated to curcumin (500 mg/day) or placebo groups for 2 months. All participants received both dietary and exercise advice. Anthropometric and biochemical measurements as well as hepatic ultrasound were performed at baseline and final conditions. RESULTS: Seventy-nine participants were recruited and randomly allocated into the curcumin (n = 39) or placebo (n = 40) groups. There were no significant differences between placebo and curcumin groups for demographic and clinical characteristics and NAFLD grade at baseline. After the treatment period, the curcumin group exhibited lower alkaline phosphatase (-16.2 ± 22.8 versus -6.0 ± 22.5 mg/dL, p = 0.04) concentrations and severity of NAFLD compared with the placebo group (p = 0.04). CONCLUSION: Results of this clinical trial suggest that short-term treatment with curcumin plus piperine administration improves NAFLD severity.

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.

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.