In vivo anticoccidial, antioxidant, and anti-inflammatory activities of avocado fruit, Persea americana (Lauraceae), against Eimeria papillata infection

Apicomplexan parasites, especially Eimeria sp., are the main intestinal murine pathogens, that lead to severe injuries to farm and domestic animals. Many anticoccidial drugs are available for coccidiosis, which, leads to the development of drug-resistant parasites. Recently, natural products are considered as an alternative agent to control coccidiosis. This study was designed to evaluate the anticoccidial activity of the Persea americana fruit extract (PAFE) in male C57BL/6 mice. A total of 35 male mice were divided into seven equal groups (1, 2, 3, 4, 5, 6, and 7). At day 0, all groups except the first group which served as uninfected-untreated control were infected orally with 1 × 10³E. papillata sporulated oocysts. Group 2 served as uninfected-treated control. Group 3 was considered an infected-untreated group. After 60 min of infection, groups 4, 5, and 6 were treated with oral doses of PAFE aqueous methanolic extract (100, 300, and 500 mg/kg of body weight, respectively). Group 7 was treated with amprolium (a reference drug for coccidiosis). PAFE with 500 mg/kg, was the most effective dose, inducing a significant reduction in the output of oocysts in mice feces (by about 85.41%), accompanied by a significant decrease in the number of the developmental parasite stages and a significant elevation of the goblet cells in the jejunal tissues. Upon treatment, a significant change in the oxidative status due to E. papillata infection was observed, where the levels of glutathione (GSH) increased, while, levels of malondialdehyde (MDA) and nitric oxide (NO) were decreased. In addition, the infection significantly upregulated the inflammatory cytokines of interleukin-1β (IL-1β), tumor necrosis factor-alpha (TNF-α), and interferon-γ (IFN-γ). This increase in mRNA expression of IL-1β, TNF-α, and IFN-γ was about 8.3, 10.6, and 4.5-fold, respectively, which significantly downregulated upon treatment. Collectively, P. americana is a promising medicinal plant with anticoccidial, antioxidant, and anti-inflammatory activities and could be used for the treatment of coccidiosis.

PLANT BASED BIOAVAILABILITY ENHANCERS

Many of the synthetic as well as herbal drugs despite of their notable in vitro finding demonstrate insignificant in vivo activity majority of times due to poor bioavailability. As per Biopharmaceutical Classification System (BCS) one of the main concern is low solubility and/or permeation of drugs resulting in reduced absorption and poor bioavailability. To overcome these issues the various strategies have been adopted including use of permeation enhancers which are also known as bioenhancers. Bioenhancers are synthetic or natural compounds that increases the bioavailability of drugs and nutrients such as vitamins, amino acids, minerals, etc. into the systemic circulation and at the site of action for exhibiting improved therapeutic action. By improving bioavailability, bioenhancers can lead to reduction in drug dose, decrease in the treatment period and can circumvent the problem of drug resistance. Numerous studies have reported application of synthetic bioenhancers. On the other hand, owing to the natural origin, plant based bioenhancer can serve as better alternative. Literature review have revealed that the plant-based bioenhancers have been used in with a wide varieties of drugs including antibiotics, antiviral and anti-cancer. These can be categorized based on their sources and the mechanism of activity. This review will provide a systematic and detailed overview of the various plant based bioenhancers and applications.

Berberine-loaded nanostructured lipid carriers mitigate warm hepatic ischemia/reperfusion-induced lesion through modulation of HMGB1/TLR4/NF-κB signaling and autophagy

OBJECTIVE

Berberine (BBR) is a known alkaloid that has verified its protective effects against ischemia/reperfusion (I/RN) lesion in multiple organs but its poor oral bioavailability limited its use. Despite the previous works, its possible impact on the warm hepatic I/RN-induced lesion is not clear. Accordingly, a nanostructured lipid carrier of BBR (NLC BBR) was developed for enhancing its efficiency and to inspect its protective mechanistic against warm hepatic I/RN.

METHODS

NLC BBR formula was evaluated pharmaceutically. Wistar rats were orally pre-treated with either BBR or NLC BBR (100 mg/kg) for 2 weeks followed by hepatic I/RN (30 min/24 h). Biochemical, ELISA, qPCR, western blot, histopathological, and immunohistochemical studies were performed.

KEY FINDINGS

Optimized NLC BBR was prepared with a particle size of 130 ± 8.3 nm. NLC BBR divulged its aptitude to safeguard the hepatic tissues partly due to anti-inflammatory capacity through downsizing the HMGB1/TLR4/NF-κB trajectory with concomitant rebating of TNF-α, iNOS, COX-2, and MPO content. Furthermore, NLC BBR antiapoptotic trait was confirmed by boosting the prosurvival protein (Bcl-2) and cutting down the pro-apoptotic marker (Bax). Moreover, its antioxidant nature was confirmed by TAC uplifting besides MDA subsiding. On the other hand, NLC BBR action embroiled autophagy flux spiking merit exemplified in Beclin-1 and LC3-II enhancement. Finally, NLC BBR administration ascertained its hepatocyte guarding action by recovering the histopathological ailment and diminishing serum transaminases.

CONCLUSION

NLC BBR purveyed reasonable shielding mechanisms and subsided incidents contemporaneous to warm hepatic I/RN lesion in part, by moderating HMGB1/TLR4/NF-κB inflammatory signaling, autophagy, and apoptosis.

A rapid LC-MS/MS method for simultaneous determination of berberine and irbesartan in rat plasma: Application to the drug-drug pharmacokinetic interaction study after oral administration in rats

A sensitive, reproducible, and specific liquid chromatography tandem mass spectrometry method was developed and validated to simultaneously determine the concentration of berberine (BBR) and irbesartan in Sprague-Dawley rat plasma, and applied to study the pharmacokinetic drug-drug interaction (DDI) between BBR and irbesartan in rats. In this method, diphenhydramine was used as the internal standard, and the liquid-liquid extraction method using ethyl acetate as the extraction agent was used for sample preparation. After extraction, the prepared samples were run on an Agilent Welchrom C₁₈ column with the mobile phase consisting of methanol-acetonitrile-water solution with 0.5% formic acid (45:50:5, v/v/v) at a flow rate of 0.8 mL·min^-1 . The analytes BBR, irbesartan, and diphenhydramine (IS) were detected using multiple reactions monitoring mode, with the ion transitions being m/z 336.1 → m/z 320.0, m/z 429.1 → m/z 206.9, and m/z 256.2 → m/z 167.0, respectively. In the rats' plasma, BBR had good linearity in the range of 0.5-100 ng·mL^-1 with the lower limit of quantitation of 0.5 ng·mL^-1 , and the accuracy, intra-day, and inter-day precision were less than 12.33%. Irbesartan had good linearity in the range of 20-1200 ng·mL^-1 with the lower limit of quantification of 20 ng·mL^-1 , and the accuracy, intra-day, and inter-day precision were less than 13.55%. The validated method was verified to meet the determination requirements of biological samples. It was the first time to study the pharmacokinetics of DDI between BBR and irbesartan successfully, which would be necessary and beneficial to explore the clinical safety and efficacy of the combination of BBR and irbesartan in the treatment of diabetic nephropathy.

Drug Bioavailability Enhancing Agents of Natural Origin (Bioenhancers) that Modulate Drug Membrane Permeation and Pre-Systemic Metabolism

Many new chemical entities are discovered with high therapeutic potential, however, many of these compounds exhibit unfavorable pharmacokinetic properties due to poor solubility and/or poor membrane permeation characteristics. The latter is mainly due to the lipid-like barrier imposed by epithelial mucosal layers, which have to be crossed by drug molecules in order to exert a therapeutic effect. Another barrier is the pre-systemic metabolic degradation of drug molecules, mainly by cytochrome P450 enzymes located in the intestinal enterocytes and liver hepatocytes. Although the nasal, buccal and pulmonary routes of administration avoid the first-pass effect, they are still dependent on absorption of drug molecules across the mucosal surfaces to achieve systemic drug delivery. Bioenhancers (drug absorption enhancers of natural origin) have been identified that can increase the quantity of unchanged drug that appears in the systemic blood circulation by means of modulating membrane permeation and/or pre-systemic metabolism. The aim of this paper is to provide an overview of natural bioenhancers and their main mechanisms of action for the nasal, buccal, pulmonary and oral routes of drug administration. Poorly bioavailable drugs such as large, hydrophilic therapeutics are often administered by injections. Bioenhancers may potentially be used to benefit patients by making systemic delivery of these poorly bioavailable drugs possible via alternative routes of administration (i.e., oral, nasal, buccal or pulmonary routes of administration) and may also reduce dosages of small molecular drugs and thereby reduce treatment costs.

Therapeutic Potential and Utility of Elacridar with Respect to P-glycoprotein Inhibition: An Insight from the Published In Vitro, Preclinical and Clinical Studies

The occurrence of efflux mechanisms via Permeability-glycoprotein (P-gp) recognized as an important physiological process impedes drug entry or transport across membranes into tissues. In some instances, either low oral bioavailability or lack of brain penetration has been attributed to P-gp mediated efflux activity. Therefore, the objective of development of P-gp inhibitors was to facilitate the attainment of higher drug exposures in tissues. Many third-generation P-gp inhibitors such as elacridar, tariquidar, zosuquidar, etc. have entered clinical development to fulfil the promise. The body of evidence from in vitro and in vivo preclinical and clinical data reviewed in this paper provides the basis for an effective blockade of P-gp efflux mechanism by elacridar. However, clinical translation of the promise has been elusive not just for elacridar but also for other P-gp inhibitors in this class. The review provides introspection and perspectives on the lack of clinical translation of this class of drugs and a broad framework of strategies and considerations in the potential application of elacridar and other P-gp inhibitors in oncology therapeutics.

Herbal Bioenhancers in Veterinary Phytomedicine

Herbal bioenhancers are active phytomolecules that increase the bioavailability, bioefficacy and biological activity of various drugs when coadministered at low concentrations. These valuable compounds reduce the dose, increase the treatment rate, decrease the treatment duration, drug resistance or related adverse reactions which have economical implications in livestock and pet medicine. Eventhough the concept of herbal bioenhancers are known for years through Ayurvedic medicine, the underlying mechanisms remains unclear. The main mechanisms involved are related to drug absorption (effect on solubility, drug efflux and transport proteins, increased permeability in gastrointestinal system) and drug metabolism (inhibition/induction of drug metabolysing enzymes, thermogenic effect). Due to species specific differences in these mechanisms, corresponding data on human and laboratory animal could not be attributed. As multidrug resistance is a major treat to both human and animal health, within "One Health" concept, efficient therapeutical strategies are encouraged by authorities, where focus on herbal supplements as a vast unexploited field remains to be researched within "Bioenhancement Concept." This review brings insight to mechanims involved in bioenhancing effect, examples of herbal extracts and phytoactive compounds and their potential in the veterinary medicine including different classes of drugs such as antibiotics, anticancerous, antiviral, and antituberculosis.

In vitro and ex vivo approach for anti-urolithiatic potential of bioactive fractions of gokhru with simultaneous HPLC analysis of six major metabolites and their exploration in rat plasma

CONTEXT

Tribulus terrestris L. (Zygophyllaceae) fruits have long been used in traditional systems of medicine for the treatment of various urinary diseases including urolithiasis.

OBJECTIVE

To explore the anti-urolithiatic potential of gokhru and to develop an analytical method for quantitative estimation of metabolites for its quality control.

MATERIALS AND METHODS

Aqueous extract of gokhru fruit was prepared through maceration followed by decoction to produce a mother extract, which was further used for polarity-based fractionations. In vitro and ex vivo anti-urolithiatic activity of mother extract and fractions at different concentration (100-1000 μg/mL) were carried out using aggregation assay in synthetic urine and in rat plasma, however, nucleation assay for 30 min was done using confocal microscopy. A simultaneous HPLC method has been developed for quantification of diosgenin, catechin, rutin, gallic acid, tannic acid and quercetin in mother extract and in fractions.

RESULTS

The extraction resulted in 14.5% of w/w mother extract, however, polarity-based fractionation yielded 2.1, 2.6, 1.5, 1.3 and 6.1% w/w of hexane, toluene, dichloromethane (DCM), n-butanol and water fractions, respectively. In vitro and ex vivo studies showed a significant anti-urolithiatic potential of n-butanol fraction. Further, HPLC analysis revealed significantly (p < 0.01) higher content of quercetin (1.95 ± 0.41% w/w), diosgenin (12.75 ± 0.18% w/w) and tannic acid (9.81 ± 0.47% w/w) in n-butanol fraction as compared to others fractions.

DISCUSSION AND CONCLUSION

In vitro and ex vivo studies demonstrated potent anti-urolithiatic activity of n-butanol fraction which can be developed as new phytopharmaceuticals for urolithiasis. HPLC method can be used for quality control and pharmacokinetic studies of gokhru.

Antiproliferation of berberine is mediated by epigenetic modification of constitutive androstane receptor (CAR) metabolic pathway in hepatoma cells

Constitutive androstane receptor (CAR) regulates hepatic xenobiotic and energy metabolism, as well as promotes cell growth and hepatocarcinogenesis. Berberine is an ancient multipotent alkaloid drug which derived from Coptis chinensis plants. Here we report that berberine is able to be cellular uptake and accessible to chromatin in human hepatoma HepG2 cells. Berberine induces more apoptosis, cell cycle arrest, but less ROS production in CAR overexpressed mCAR-HepG2 cells. Moreover, berberine inhibits expressions of CAR and its target genes CYP2B6 and CYP3A4. Furthermore, berberine enhances DNA methylation level in whole genome but reduces that in promoter regions CpG sites of CYP2B6 and CYP3A4 genes under the presence of CAR condition. These results indicated that the antiproliferation of berberine might be mediated by the unique epigenetic modifying mechanism of CAR metabolic pathway, suggesting that berberine is a promising candidate in anticancer adjuvant chemotherapy, due to its distinct pharmacological properties in clinic.

Review of Scientific Evidence of Medicinal Convoy Plants in Traditional Persian Medicine

One concept used in traditional Persian medicine (TPM) for multidrug therapy is that of the convoy drug (Mobadregh). According to TPM texts, convoy drugs are substances (or drugs), which facilitate the access of drugs or foods to the whole body or to specific organs. This study reviewed some convoy drugs presented in TPM, their biological effects, and their probable interactions with main drugs, considering the increased absorption through inhibition of P-glycoprotein (P-gp) efflux function, bioavailability-enhancing effects, and decreased metabolism of the main drug using electronic databases including PubMed, Scopus, ScienceDirect, and Google Scholar in November and December, 2013. Recent studies have proven the beneficial effects of Crocus sativus L. (saffron) and camphor on the heart and brain, the cerebral therapeutic effects of Asarum europaeum (hazelwort), the hepatoprotective effects of Cichorium intybus (chicory), and Apium graveolens (celery) seeds, and the diuretic effects of Cinnamomum zeylanicum (cinnamon), and Cucumis melo (melon) seeds. The effects of vinegar in targeting the liver and brain have also been demonstrated. An evaluation of the results demonstrated that the suggested convoy drugs, including Piper nigrum (black pepper), Piper longum (long pepper), red wine, Camellia sinensis (tea), hazelwort, Mentha longifolia (pennyroyal), Anethum graveolens (dill), Foeniculum vulgare (fennel), cinnamon, and Sassafras albidum (sassafras) can increase the bioavailability of coadministered drugs by inhibition of P-gp or cytochrome P450s (CYP450s) or both of them. This evidence could be a good basis for the use of these agents as convoys in TPM.

A mechanistic investigation of the bioavailability enhancing potential of lysergol, a novel bioenhancer, using curcumin

Lysergol (LYZ), a novel bioenhancer, has shown potential to enhance the bioavailability of curcumin.

Sample preparation for liquid chromatographic analysis of phytochemicals in biological fluids

INTRODUCTION

Natural products have been used traditionally for the treatment and prevention of diseases for thousands of years and are nowadays consumed as dietary supplements and herbal medicine. To ensure the safe and effective use of these herbal products, information about bioavailability of active compounds in plasma or target tissues should be provided via validated analytical methods combined with appropriate sampling methods.

OBJECTIVE

To provide comprehensive and abridged information about sample preparation methods for the quantification of phytochemicals in biological samples using liquid chromatography analysis.

METHODS

Sample pre-treatment procedures used in analytical methods for in vivo pharmacokinetic studies of natural compounds or herbal medicines were reviewed. These were categorised according to the biological matrices (plasma, bile, urine, faeces and tissues) and sample clean-up processes (protein precipitation, liquid-liquid extraction and solid-phase extraction).

RESULTS

Although various kinds of sample pre-treatment methods have been developed, liquid-liquid extraction is still widely used and solid-phase extraction is becoming increasingly popular because of its efficiency for extensive clean up of complex matrix samples. However, protein precipitation is still favoured due to its simplicity.

CONCLUSION

Sample treatment for phytochemical analysis in biological fluids is an indispensable and critical step to obtain high quality results. This step could dominate the overall analytical process because both the duration of the process as well as the reliability of the data depend in large part on its efficiency. Thus, special attention should be given to the choice of a proper sample treatment method that targets analytes and their biomatrix.

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.