Role of piperine in CNS diseases: pharmacodynamics, pharmacokinetics and drug interactions

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

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

Potential of piperine for neuroprotection in sepsis-associated encephalopathy

AIMS

Sepsis-associated encephalopathy (SAE) is a common complication that increases mortality and leads to long-term cognitive impairment in sepsis survivors. However, no specific or effective therapy has been identified for this complication. Piperine is an alkaloid known for its anti-inflammatory, antioxidant, and neuroprotective properties, which are important characteristics for treatment of SAE. The objective of this study was to evaluate the neuroprotective effect of piperine on SAE in C57BL/6 mice that underwent cecum ligation and perforation surgery (CLP).

MAIN METHODS

C57BL/6 male mice were randomly assigned to groups that underwent SHAM surgery or CLP. Mice in the CLP group were treated with piperine at doses of 20 or 40 mg/kg for short- (5 days) or long-term (10 days) periods after CLP.

KEY FINDINGS

Our results revealed that untreated septic animals exhibited increased concentrations of IL-6, TNF, VEGF, MMP-9, TBARS, and NLRP3, and decreased levels of BDNF, sulfhydryl groups, and catalase in the short term. Additionally, the levels of carbonylated proteins and degenerated neuronal cells were increased at both time points. Furthermore, short-term and visuospatial memories were impaired. Piperine treatment reduced MMP-9 activity in the short term and decreased the levels of carbonylated proteins and degenerated neuronal cells in the long term. It also lowered IL-6 and TBARS levels at both time points evaluated. Moreover, piperine increased short-term catalase and long-term BDNF factor levels and improved memory at both time points.

SIGNIFICANCE

In conclusion, our data demonstrate that piperine exerts a neuroprotective effect on SAE in animals that have undergone CLP.

Therapeutic considerations of bioactive compounds in Alzheimer's disease and Parkinson's disease: Dissecting the molecular pathways

Leading neurodegenerative diseases Alzheimer's disease (AD) and Parkinson's disease (PD) are characterized by the impairment of memory and motor functions, respectively. Despite several breakthroughs, there exists a lack of disease-modifying treatment strategies for these diseases, as the available drugs provide symptomatic relief and bring along side effects. Bioactive compounds are reported to bear neuroprotective properties with minimal toxicity, however, a detailed elucidation of their modes of neuroprotection is lacking. The review elucidates the neuroprotective mechanism(s) of some of the major phyto-compounds in pre-clinical and clinical studies of AD and PD to understand their potential in combating these diseases. Curcumin, eugenol, resveratrol, baicalein, sesamol and so on have proved efficient in countering the pathological hallmarks of AD and PD. Curcumin, resveratrol, caffeine and so on have reached the clinical phases of these diseases, while aromadendrin, delphinidin, cyanidin and xanthohumol are yet to be extensively explored in pre-clinical phases. The review highlights the need for extensive investigation of these compounds in the clinical stages of these diseases so as to utilize their disease-modifying abilities in the real field of treatment. Moreover, poor pharmacokinetic properties of natural compounds are constraints to their therapeutic yields and this review suggests a plausible contribution of nanotechnology in overcoming these limitations.

Neurotrophic basis to the pathogenesis of depression and phytotherapy

Depression is a major neuropsychiatric disease that considerably impacts individuals’ psychosocial function and life quality. Neurotrophic factors are now connected to the pathogenesis of depression, while the definitive neurotrophic basis remains elusive. Besides, phytotherapy is alternative to conventional antidepressants that may minimize undesirable adverse reactions. Thus, further research into the interaction between neurotrophic factors and depression and phytochemicals that repair neurotrophic factors deficit is highly required. This review highlighted the implication of neurotrophic factors in depression, with a focus on the brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), vascular endothelial growth factor (VEGF), and nerve growth factor (NGF), and detailed the antidepressant activities of various phytochemicals targeting neurotrophic factors. Additionally, we presented future opportunities for novel diagnostic and therapeutic strategies for depression and provided solutions to challenges in this area to accelerate the clinical translation of neurotrophic factors for the treatment of depression.

Piperine Provides Neuroprotection against Kainic Acid-Induced Neurotoxicity via Maintaining NGF Signalling Pathway

The neuroprotective properties of piperine, the major alkaloid extracted from black pepper, have been under investigation, but its mechanism of action in excitotoxicity is still poorly understood. This study aimed to evaluate the protective effects of piperine with a focus on nerve growth factor (NGF) signalling in a kainic acid (KA) rat model of excitotoxicity. Rats were administered intraperitoneally (i.p.) piperine (10 or 50 mg/kg) before KA injection (15 mg/kg, i.p.). Our results show that KA exposure in rats caused seizure behaviour, intrinsic neuronal hyperactivity, glutamate elevation, hippocampal neuronal damage, and cognitive impairment. These KA-induced alterations could be restored to the normal state by piperine treatment. In addition, piperine decreased the expression of the NGF precursor proNGF and NGF-degrading protease matrix metalloproteinase 9, whereas it increased the expression of proNGF processing enzyme matrix metalloproteinase 7, NGF, and NGF-activated receptor TrkA in the hippocampus of KA-treated rats. Furthermore, KA decreased phosphorylation of the protein kinase B (Akt) and glycogen synthase kinase 3β (GSK3β) in the hippocampus, and piperine reversed these changes. Our data suggest that piperine protects hippocampal neurons against KA-induced excitotoxicity by upregulating the NGF/TrkA/Akt/GSK3β signalling pathways.

Molecular and pharmacological aspects of piperine as a potential molecule for disease prevention and management: evidence from clinical trials

BACKGROUND

Piperine is a type of amide alkaloid that exhibits pleiotropic properties like antioxidant, anticancer, anti-inflammatory, antihypertensive, hepatoprotective, neuroprotective and enhancing bioavailability and fertility-related activities. Piperine has the ability to alter gastrointestinal disorders, drug-metabolizing enzymes, and bioavailability of several drugs. The present review explores the available clinical and preclinical data, nanoformulations, extraction process, structure-activity relationships, molecular docking, bioavailability enhancement of phytochemicals and drugs, and brain penetration properties of piperine in the prevention, management, and treatment of various diseases and disorders.

MAIN BODY

Piperine provides therapeutic benefits in patients suffering from diabetes, obesity, arthritis, oral cancer, breast cancer, multiple myeloma, metabolic syndrome, hypertension, Parkinson's disease, Alzheimer's disease, cerebral stroke, cardiovascular diseases, kidney diseases, inflammatory diseases, and rhinopharyngitis. The molecular basis for the pleiotropic activities of piperine is based on its ability to regulate multiple signaling molecules such as cell cycle proteins, anti-apoptotic proteins, P-glycoprotein, cytochrome P450 3A4, multidrug resistance protein 1, breast cancer resistance protein, transient receptor potential vanilloid 1 proinflammatory cytokine, nuclear factor-κB, c-Fos, cAMP response element-binding protein, activation transcription factor-2, peroxisome proliferator-activated receptor-gamma, Human G-quadruplex DNA, Cyclooxygenase-2, Nitric oxide synthases-2, MicroRNA, and coronaviruses. Piperine also regulates multiple signaling pathways such as Akt/mTOR/MMP-9, 5'-AMP-activated protein kinase-activated NLR family pyrin domain containing-3 inflammasome, voltage-gated K+ current, PKCα/ERK1/2, NF-κB/AP-1/MMP-9, Wnt/β-catenin, JNK/P38 MAPK, and gut microbiota.

SHORT CONCLUSION

Based on the current evidence, piperine can be the potential molecule for treatment of disease, and its significance of this molecule in the clinic is discussed.

GRAPHICAL ABSTRACT

A review on the bioavailability, bio-efficacies and novel delivery systems for piperine

As the major naturally occurring alkaloid in pepper with a pungent taste, piperine is known for its beneficial biological functions and therapeutic effects. In this work, the bioavailability and biological activities of piperine were presented and discussed. Novel delivery systems for enhancing the bioavailability of piperine were also reviewed. This study could provide a better understanding of the physiological and biochemical aspects of piperine to be further developed in the food and nutraceutical industries.

Global survey of medicinal plants during lactation and postpartum recovery: Evolutionary perspectives and contemporary health implications

ETHNOPHARMACOLOGICAL RELEVANCE

Cross-cultural comparison of plants used during lactation and the postpartum period offers insight into a largely overlooked area of ethnopharmacological research. Potential roles of phytochemicals in emerging models of interaction among immunity, inflammation, microbiome and nervous system effects on perinatal development have relevance for the life-long health of individuals and of populations in both traditional and contemporary contexts.

AIM OF THE STUDY

Delineate and interpret patterns of traditional and contemporary global use of medicinal plants ingested by mothers during the postpartum period relative to phytochemical activity on immune development and gastrointestinal microbiome of breastfed infants, and on maternal health.

MATERIALS AND METHODS

Published reviews and surveys on galactagogues and postpartum recovery practices plus ethnobotanical studies from around the world were used to identify and rank plants, and ascertain regional use patterns. Scientific literature for 20 most-cited plants based on frequency of publication was assessed for antimicrobial, antioxidant, anti-inflammatory, immunomodulatory, antidepressant, analgesic, galactagogic and safety properties.

RESULTS

From compilation of 4418 use reports related to 1948 species, 105 plant taxa were recorded ≥7 times, with the most frequently cited species, Foeniculum vulgare, Trigonella foenum-graecum, Pimpinella anisum, Euphorbia hirta and Asparagus racemosus, 81, 64, 42, 40 and 38 times, respectively. Species and use vary globally, illustrated by the pattern of aromatic plants of culinary importance versus latex-producing plants utilized in North Africa/Middle East and Sub-Saharan Africa with opposing predominance. For 18/20 of the plants a risk/benefit perspective supports assessment that positive immunomodulation and related potential exceed any safety concerns. Published evidence does not support a lactation-enhancing effect for nearly all the most-cited plants while antidepressant data for the majority of plants are predominately limited to animal studies.

CONCLUSIONS

Within a biocultural context traditional postpartum plant use serves adaptive functions for the mother-infant dyad and contributes phytochemicals absent in most contemporary diets and patterns of ingestion, with potential impacts on allergic, inflammatory and other conditions. Polyphenolics and other phytochemicals are widely immunologically active, present in breast milk and predominately non-toxic. Systematic analysis of phytochemicals in human milk, infant lumen and plasma, and immunomodulatory studies that differentiate maternal ingestion during lactation from pregnancy, are needed. Potential herb-drug interaction and other adverse effects should remain central to obstetric advising, but unless a plant is specifically shown as harmful, considering potential contributions to health of individuals and populations, blanket advisories against postpartum herbal use during lactation appear empirically unwarranted.

Piperine-Coated Gold Nanoparticles Alleviate Paraquat-Induced Neurotoxicity in Drosophila melanogaster

Parkinson's disease (PD) is the most common progressive neurodegenerative disease known to impart bradykinesia leading to diverse metabolic complications. Currently, scarcity of effective drug candidates against this long-term devastating disorder poses a big therapeutic challenge. Here, we have synthesized biocompatible, polycrystalline, and uniform piperine-coated gold nanoparticles (AuNPs^piperine) to specifically target paraquat-induced metabolic complications both in Drosophila melanogaster and SH-SY5Y cells. Our experimental evidence clearly revealed that AuNPs^piperine can effectively reverse paraquat-induced lethal effects in both in vitro and in vivo model systems of PD. AuNPs^piperine were found to suppress oxidative stress and mitochondrial dysfunction, leading to inhibition of apoptotic cell death in paraquat-treated flies. AuNPs^piperine were also found to protect SH-SY5Y cells against paraquat-induced toxicity at the cellular level preferably by maintaining mitochondrial membrane potential. Both experimental and computational data point to the possible influence of AuNPs^piperine in regulating the homeostasis of parkin and p53 which may turn out to be the key factors in reducing PD symptoms. The findings of this work may facilitate the development of piperine-based nanoformulations against PD.

Piperine Attenuates TBI-Induced Seizures via Inhibiting Cytokine-Activated Reactive Astrogliosis

Peppers have been used in clinics for a long time and its major component, piperine (PPR), has been proven to be effective in the treatment of seizures. The purpose of this study was to investigate the effects of piperine on early seizures in mice after a traumatic brain injury (TBI) and to explore the mechanism of the drug against the development on TBI. Specific-pathogen-free-grade mice were randomly divided into six dietary groups for a week: control group, TBI group, three piperine groups (low PPR group with 10 mg/kg PPR, medium PPR group with 20 mg/kg PPR, and high PPR group with 40 mg/kg PPR), and a positive control group (200 mg/kg valproate). Except for the control group, all the other groups used Feeney free weight falling method to establish the TBI of closed brain injury in mice, and the corresponding drugs were continuously injected intraperitoneally for 7 days after the brain injury. The results from behavior and electroencephalogram showed that piperine attenuated the subthreshold dose of pentylenetetrazole-induced seizures compared with the TBI group. The western blot results showed that the expression levels of inflammatory factors tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were reduced by piperine. The immunostaining results showed that the brain-derived neurotrophic factor (BDNF) was also reduced by piperine. In addition, positive cell counts of astrocytic fibrillary acidic protein (GFAP) in immuno-fluorescence showed that they were also reduced. Our data show that piperine treatment can reduce the degree of cerebral edema, down-regulate TNF-α, IL-1β, and BDNF, decrease the reactivity of GFAP in the hippocampus, and inhibit TBI-induced seizures.

Natural product piperine alleviates experimental allergic encephalomyelitis in mice by targeting dihydroorotate dehydrogenase

Multiple sclerosis (MS) is the most popular chronic and debilitating inflammatory disease of the central nervous system (CNS) that remains incurable. Dihydroorotate dehydrogenase (DHODH) is critical to the activity of T lymphocytes and represents a potential therapeutic target for MS. Here we identify piperine, a bioactive constituent of black pepper, as a potent inhibitor of DHODH with an IC₅₀ value of 0.88 μM. Isothermal titration calorimetry and thermofluor assay demonstrate the directly interaction between piperine and DHODH. The co-complex crystal structure of DHODH and piperine at 1.98 Å resolution further reveal that Tyr356 residue of DHODH is crucial for piperine binding. Importantly, we show that piperine can inhibit T cell overactivation in a DHODH-dependent manner in concanavalin A-triggered T-cell assay and mixed lymphocyte reaction assay. Finally, piperine exhibits strong preventive and therapeutic effect in the MOG-induced experimental allergic encephalomyelitis (EAE), a useful model for studying potential treatments for MS, by restricting inflammatory cells infiltration into the CNS and preventing myelin destruction and blood-brain barrier (BBB) disruption. Taken together, these findings highlight DHODH as a therapeutic target for autoimmune disease of the nervous system, and demonstrate a novel role for piperine in the treatment of MS.