Improved oral bioavailability of capsaicin via liposomal nanoformulation: preparation, in vitro drug release and pharmacokinetics in rats

In situ encapsulation of capsaicinoids in MIL-88A as a food-grade nanopreservative for meat safety

The biocompatible MIL-88A metal-organic framework (MOF), synthesized from food-grade fumaric acid and ferric chloride, was introduced for the efficient one-step in situ encapsulation of capsaicinoids as a nanopreservative. The resulting MIL-88A@Caps nanoparticles can load 61.43 mg/g of capsaicinoids, surpassing conventional MOF-based encapsulation. The potent MIL-88A@Caps nanoformulations synergize the intrinsic antimicrobial properties of MIL-88A and capsaicinoids. At the same concentration (0.5 mg/mL), MIL-88A@Caps was highly effective against S. aureus and Salmonella, with inhibition rates of 94.90 ± 0.58% and 94.30 ± 1.24%, respectively, compared to MIL-88A (62.28 ± 5.04% and 70.46 ± 1.96%) and capsaicinoids (63.68 ± 1.25% and 49.53 ± 1.22%), respectively. Model precooked-chicken preservation experiments revealed that MIL-88A@Caps significantly delayed spoilage parameters compared to untreated samples, with more favorable viable counts (8.08 lgCFU/g), pH value (6.60 ± 0.02), TVB-N value (8.59 ± 0.21 mg/100 g), and color changes on day 9. Our findings yield a green nanopreservative for meat safety.

Enhanced oral bioavailability and in vitro evaluation of cannabidiol camel milk-derived exosome formulation in resistant MDA-MB-231 and MDA-MB-468 breast cancer cells

The potential of camel milk-derived exosomes (CMDE) to enhance the bioavailability of Cannabidiol (CBD) was investigated. CBD-CMDE formulation was prepared using an established procedure and its particle size was 138.4 ± 4.37 nm, and CBD entrapment efficiency of 56.56 ± 4.26 %. In-vitro release studies showed release of 78.27 ± 5.37 % and 46.42 ± 4.75 % CBD from CMDE and control CBD formulation respectively in pH 6.8 at 24 hr. The apparent permeability (Papp) of CBD-CMDE was found to be enhanced by 3.95-fold with Papp of 22.9*10-6 ± 0.34 cm/sec as compared to control CBD formulation with Papp of 5.8*10-6 ± 0.65 cm/sec in MDCK cells. CBD-CMDE was found to be more potent than CBD in 2D cytotoxicity assay with IC50 values of 3.6 ± 0.54 µM, 3.88 ± 0.54 µM and 7.53 ± 0.59 µM, 7.53 ± 0.59 µM against Doxorubicin (DOX) resistant MDA-MB-231 and Rapamycin (RM) resistant MDA-MB-468 breast cancer cells respectively. Moreover, 3D spheroids assay results demonstrated CBD-CMDE with IC50 values of 14 ± 0.85 µM, 15 ± 0.07 µM as compared to CBD alone with IC50 values of 25 ± 0.93 µM, 34.7 ± 0.08 µM in MDA-MB-231 DOX RT cells and MDA-MB-468 RM RT cells respectively. In-vivo PK studies showed enhanced bioavailability of CBD from CBD-exosomes with AUC(0-24h) of 1350.56 ± 187.50 h.ng/mL as compared to CBD control formulation with AUC(0-24h) of 351.95 ± 39.10 h.ng/mL with a single oral dose of 12 mg/kg. The data indicate that CMDE significantly improved the oral bioavailability of CBD. Overall, CMDE can be used to enhance the oral absorption of poorly bioavailable APIs.

The pulmonary protective potential of vanillic acid-loaded TPGS-liposomes: modulation of miR-217/MAPK/NF-κb signalling pathway

The aim is to investigate the possible pulmonary protective effect of vanillic acid (VA) in liposome-TPGS nanoparticles, to overcome VA's poor bioavailability. VA was successfully extracted. Liposomes were prepared using thin film hydration. Central composite design was adopted for optimisation of liposomes to get the maximum entrapment efficiency (EE%) and the minimum mean diameter, where the liposomes were further modified with TPGS, and tested for PDI, zeta-potential, and in-vitro drug release. In-vivo study on mice with LPS-acute pulmonary toxicity was tested. TPGS-modified VA-liposomes showed EE% of 69.35 ± 1.23%, PS of 201.7 ± 3.23 nm, PDI of 0.19 ± 0.02, and zeta-potential of -32.2 ± 0.32 mv. A sustained drug release of the TPGS-modified VA-liposomes was observed compared to standard VA, and a pulmonary-protective effect through decreasing miR-217 expression with subsequent anti-inflammatory effect through suppression of MAPK and PI3K/NF-κB pathways was also demonstrated in the current study. TPGS-modified VA-liposomes showed an enhanced bioavailability and a sustained drug release with promising pulmonary protective effects against acute pulmonary injury diseases.

Development of Pegylated Nano-Phytosome Formulation with Oleuropein and Rutin to Compare Anti-Colonic Cancer Activity with Olea Europaea Leaves Extract

Olive leaf extract is a valuable source of phenolic compounds; primarily, oleuropein (major component) and rutin. This natural olive leaf extract has potential use as a therapeutic agent for cancer treatment. However, its clinical application is hindered by poor pharmacokinetics and low stability. To overcome these limitations, this study aimed to enhance the anticancer activity and stability of oleuropein and rutin by loading them into PEGylated Nano-phytosomes. The developed PEGylated Nano-phytosomes exhibited favorable characteristics in terms of size, charge, and stability. Notably, the anticolonic cancer activity of the Pegylated Nano-phytosomes loaded with oleuropein (IC50=0.14 μM) and rutin (IC50=0.44 μM) surpassed that of pure oleuropein and rutin alone. This outcome highlights the advantageous impact of Nano-phytosomes to augment the anticancer potential of oleuropein and rutin. These results present a promising pathway for the future development of oleuropein and rutin Nano-phytosomes as effective options for passive tumor-targeted therapy, given their improved stability and efficacy.

Advancement in Solubilization Approaches: A Step towards Bioavailability Enhancement of Poorly Soluble Drugs

A drug's aqueous solubility is defined as the ability to dissolve in a particular solvent, and it is currently a major hurdle in bringing new drug molecules to the market. According to some estimates, up to 40% of commercialized products and 70-90% of drug candidates in the development stage are poorly soluble, which results in low bioavailability, diminished therapeutic effects, and dosage escalation. Because of this, solubility must be taken into consideration when developing and fabricating pharmaceutical products. To date, a number of approaches have been investigated to address the problem of poor solubility. This review article attempts to summarize several conventional methods utilized to increase the solubility of poorly soluble drugs. These methods include the principles of physical and chemical approaches such as particle size reduction, solid dispersion, supercritical fluid technology, cryogenic technology, inclusion complex formation techniques, and floating granules. It includes structural modification (i.e., prodrug, salt formation, co-crystallization, use of co-solvents, hydrotrophy, polymorphs, amorphous solid dispersions, and pH variation). Various nanotechnological approaches such as liposomes, nanoparticles, dendrimers, micelles, metal organic frameworks, nanogels, nanoemulsions, nanosuspension, carbon nanotubes, and so forth have also been widely investigated for solubility enhancement. All these approaches have brought forward the enhancement of the bioavailability of orally administered drugs by improving the solubility of poorly water-soluble drugs. However, the solubility issues have not been completely resolved, owing to several challenges associated with current approaches, such as reproducibility in large scale production. Considering that there is no universal approach for solving solubility issues, more research is needed to simplify the existing technologies, which could increase the number of commercially available products employing these techniques.

Encapsulation of resveratrol within size-controlled nanoliposomes: Impact on solubility, stability, cellular permeability, and oral bioavailability

This study examined the influence of the nanoliposomes (LPs) particle size on the solubility, antioxidant stability, in vitro release profile, Caco-2 cellular transport activity, cellular antioxidant activity, and in vivo oral bioavailability of resveratrol (RSV). LPs with sizes of 300, 150, and 75 nm were prepared using the thin-lipid film hydration method, followed by ultrasonication for 0, 2, and 10 min, respectively. Formulating small LPs (< 100 nm) was effective to enhance the solubility, in vitro release profile, cellular permeability, and cellular antioxidant activity of RSV. A similar pattern was observed for in vivo oral bioavailability. However, the size reduction of RSV-loaded LPs did not promote the antioxidant stability of RSV, owing to their large surface area used to interact with harsh environments. This study provides the better understanding of the appropriate particle size range of LPs to improve their in vitro and in vivo performances of RSV as an effective carrier for oral administration.

Microfluidic Generation of Near-Infrared Photothermal Vitexin/ICG Liposome with Amplified Photodynamic Therapy

Glioma, in which a malignant tumor cell occurs in neural mesenchymal cells, has a rapid progression and poor prognosis, which is still far from desirable in clinical treatments. We developed a lab-on-a-chip (LOC) device for the rapid and efficient preparation of vitexin/indocyanine green (ICG) liposomes. Vitexin could be released from liposome to kill cancer cell, which can potentially improve the glioma therapeutic effect and reduce the treatment time through synergistic photodynamic/photothermal therapies (PDT/PTT). The vitexin/ICG liposome was fabricated via LOC and its physicochemical property and release in vitro were evaluated. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method and live/dead staining were used to examine the enhanced antitumor effect of vitexin/ICG liposome in cooperation with PDT/PTT, while the related mechanism was explored by flow cytometry and western blot. The results were as follows: (1) The prepared vitexin/ICG liposome was smaller in size, homogenous in particle size distribution with significant low polydispersity index (PDI), and enhanced cumulative release in vitro. (2) We found that the formulated liposome presented strong cancer cell inhibition and suppression of its migration in a dose-dependent manner. (3) Further mechanistic studies showed that liposome combined with near-infrared irradiation could significantly upregulate levels of B cell lymphoma 2-associated X (Bax) protein and decrease B cell lymphoma 2 (Bcl-2) at protein levels. The vitexin/ICG liposomes prepared based on a simple LOC platform can effectively enhance the solubility of insoluble drugs, and the combined effect of PTT/PDT can effectively increase their antitumor effect, which provides a simple and valid method for the clinical translation of liposomes.

A Sojourn on Liposomal Delivery System: Recent Advances and Future Prospects

Liposomes are unique novel drug delivery carriers that favor the effective transportation of pharmaceuticals. These vesicles acquire one or more phospholipid bilayer membranes, and an inner aqueous core can carry both aqueous and lipid drugs. While hydrophilic molecules can be confined in the aqueous core, hydrophobic molecules are injected into the bilayer membrane. Liposomes have many benefits as a drug delivery method, including biocompatibility, the capacity to carry large drug payloads, and a variety of physicochemical and biological parameters that can be altered to influence their biological characteristics. In addition, being a size of 10-100 nm range can have numerous additional benefits, including enhanced pharmacokinetics, clever escape from the reticuloendothelial system, greater in vivo stability, longer and site-specific administration, and increased internalization in tumor tissue (enhanced permeability and retention impact). The current review focuses on the structural composition of liposomes, formulation technologies, and suitable case studies for optimizing biopharmaceutical performance. Moreover, clinical trials and marketed formulations of liposomes have been also stated in the prior art.

Digestion behaviour of capsaicinoid-loaded emulsion gels and bioaccessibility of capsaicinoids: Effect of emulsifier type

In this study, the effect of emulsifier type, i.e. whey protein versus Tween 80, on the digestion behaviour of emulsion gels containing capsaicinoids (CAPs) was examined. The results indicate that the CAP-loaded Tween 80 emulsion gel was emptied out significantly faster during gastric digestion than the CAP-loaded whey protein emulsion gel. The Tween-80-coated oil droplets appeared to be in a flocculated state in the emulsion gel, had no interactions with the protein matrix and were easily released from the protein matrix during gastric digestion. The whey-protein-coated oil droplets showed strong interactions with the protein matrix, and the presence of thick protein layer around the oil droplets protected their liberation during gastric digestion. During intestinal digestion, the CAP-loaded Tween 80 emulsion gel had a lower extent of lipolysis than the CAP-loaded whey protein emulsion gel, probably because the interfacial layer formed by Tween 80 was resistance to displacement by bile salts, and/or because Tween 80 formed interfacial complexes with bile salts/lipolytic enzymes. Because of the softer structure of the CAP-loaded Tween 80 emulsion gel, the gel particles were broken down much faster and the oil droplets were liberated from the protein matrix more readily than for the CAP-loaded whey protein emulsion gel during intestinal digestion; this promoted the release of CAP molecules from the gel. In addition, the Tween 80 molecules displaced from the interface would participate in the formation of mixed micelles and would help to solubilize the released CAP molecules, leading to improved bioaccessibility of CAP. Information obtained from this study could be useful in designing functional foods for the delivery of lipophilic bioactive compounds.

Preparation, in vitro and in vivo evaluation of pinocembrin-loaded TPGS modified liposomes with enhanced bioavailability and antihyperglycemic activity

PURPOSE

To prepare polyethylene glycol succinate-vitamin E modified pinocembrin (PCB)-loaded liposomes (PCBT-liposomes) and evaluate PCBT-liposomal pharmacokinetics and antihyperglycemic activity.

SIGNIFICANCE

The novel PCBT-liposomes demonstrated a promising application prospect as a nano drug carrier for future research.

METHODS

Thin film dispersion was used to prepare PCBT-liposomes. We measured a series of characterization, followed by in vitro cumulative release, in vivo pharmacokinetic study, and antihyperglycemic activity evaluation.

RESULTS

PCBT-liposomes displayed spherical and bilayered nanoparticles with mean particle size (roughly 92 nm), negative zeta potential (about -26.650 mV), high drug encapsulation efficiency (87.32 ± 1.34%) and good storage (at 4 or 25 °C) stability during 48 h after hydration. The cumulative release rate of PCBT-liposomes was markedly higher than free PCB in four different pH media. In vivo investigation showed that PCBT-liposomes could obviously improve oral bioavailability of PCB by 1.96 times, whereas the C_max, MRT_0-t, and T_1/2 of PCBT-liposomes were roughly 1.700 ± 0.139 µg·mL^-1, 12.695 ± 1.647 h, and 14.244 h, respectively. In terms of biochemical analysis, aspartate amino-transferase (AST), alanine amino-transferase (ALT), interleukin-1 (IL-1), and tumor necrosis factor-α (TNF-α) concentrations in serum of diabetic mice were respectively decreased 28.28%, 17.23%, 17.77%, and 8.08% after PCBT-liposomal treatment.

CONCLUSION

These results show PCBT-liposomal preparation as an excellent nano-carrier which has the potential to improve water solubility, bioavailability, and antihyperglycemic activity of PCB, amid broadening the application of PCB in the clinical settings.

Acyclic cucurbit[n]urils-based supramolecular encapsulation for enhancing the protective effect of capsaicin on gastric mucosa and reducing irritation

Capsaicin (CAP) is an alkaloid isolated from pepper fruit, which possesses various pharmacological activities including antioxidant, anti-inflammatory, antibacterial and gastric mucosa protection. However, its inherent poor aqueous solubility and strong irritation impede the further clinical application. In our study, acyclic cucurbit[n]urils (ACBs, M1, M2 and M3) were rationally utilized to prepare a series of CAP inclusion complexes to improve the bioavailability and reduce stimulation. Their properties and inclusion behaviors were further investigated by multiple characterization methods, the data indicated that the inclusion complexes of ACBs/CAP were formed by a stoichiometric ratio of 2:1 with strong binding interaction. After complexation, the solubility of CAP was significantly increased by 12,076 times and its antioxidant activity also increased. Moreover, the anti-inflammatory activity and the ability to prevent gastric mucosal injury were both significantly improved, and the inhibition rate of nitric oxide (NO) and interleukin-1β (IL-1β) has been effectively improved while cytotoxicity against human normal hepatocytes cell (LO2), human lung fibroblasts cell (HLF) and the human gastric mucosal cell (GES-1) was greatly attenuated. Confocal laser scanning microscope (CLSM) images indicated that the complexes could be efficiently internalized by GES-1 cells and primarily located in cytoplasm. In vivo model of mouse, our complexes exhibited excellent biosafety. In summary, our study may provide a promising new strategy for the further clinical application of CAP.

One-Step Encapsulation of Capsaicin into Chitosan-Oleic Acid Complex Particles: Evaluation of Encapsulation Ability and Stability

Capsaicin (CAP) demonstrates a potential for application in the food and pharmaceutical industries owing to its various attractive health benefits, including anti-cancer, anti-inflammatory, and antioxidant activities. However, the application of CAP is often limited by its low solubility in water, low bioavailability, and strong pungency. In this study, a simple one-step method for the stable encapsulation and dispersion of CAP in aqueous media was developed using polyelectrolyte complex particles formed by chitosan (CHI) and oleic acid (OA). Homogeneous particles with mean diameters below 1 μm were successfully prepared via spontaneous molecular complexation by mixing an aqueous solution of CHI with an ethanolic solution of OA and CAP. CAP was incorporated into the hydrophobic domains of the CHI-OA complex particles through hydrophobic interactions between the alkyl chains of OA and CAP. The factors affecting CAP encapsulation were investigated, and a maximum encapsulation yield of approximately 100% was obtained. The CHI-OA-CAP complex particles could be stored for more than 3 months at room temperature (22-26 °C) without resulting in macroscopic phase separation or degradation of CAP. We believe that our findings provide a useful alternative encapsulation technique for CAP and contribute to expanding its practical application.

Bioactive Loaded Novel Nano-Formulations for Targeted Drug Delivery and Their Therapeutic Potential

Plant-based medicines have received a lot of attention in recent years. Such medicines have been employed to treat medical conditions since ancient times, and in those times only the observed symptoms were used to determine dose accuracy, dose efficacy, and therapy. Rather than novel formulations, the current research work on plant-based medicines has mostly concentrated on medicinal active phytoconstituents. In the past recent decades, however, researchers have made significant progress in developing "new drug delivery systems" (NDDS) to enhance therapeutic efficacy and reduce unwanted effects of bioactive compounds. Nanocapsules, polymer micelles, liposomes, nanogels, phytosomes, nano-emulsions, transferosomes, microspheres, ethosomes, injectable hydrogels, polymeric nanoparticles, dendrimers, and other innovative therapeutic formulations have all been created using bioactive compounds and plant extracts. The novel formulations can improve solubility, therapeutic efficacy, bioavailability, stability, tissue distribution, protection from physical and chemical damage, and prolonged and targeted administration, to name a few. The current study summarizes existing research and the development of new formulations, with a focus on herbal bioactive components.

Emerging trends in nano-bioactive-mediated mitochondria-targeted therapeutic stratagems using polysaccharides, proteins and lipidic carriers

The emergence of new lifestyle disorders and pharmaco-resistant variants of diseases has necessitated the search for effective therapeutic moieties and approaches that could overcome the limitations in the existing treatment modalities. In this context, bioactives such as flavonoids, polyphenols, tannins, terpenoids and alkaloids have demonstrated promise in therapy owing to their ability to scavenge free radicals and modulate the mitochondrial function as well as regulate metabolic pathways. However, their clinical applicability is low owing to their poor bioavailability and aqueous solubility. The encapsulation of bioactives in nanodimensional particles has overcome these limitations to a large extent while simultaneously conferring additional advantages of improved circulation time, enhanced cell uptake and target specific release. A wide range of nanocarriers derived from biopolymers such as polysaccharides, lipids and proteins, have been explored for encapsulation of different bioactives and have reported significant improvement of the bioavailability and therapeutic efficacy of the encapsulated cargo. However, incorporation of cell-specific and mitochondria-specific elements on the nanocarriers has been relatively less explored. This review summarizes some of the recent attempts to treat different disorders using bioactives encapsulated in biopolymer nanostructures and few instances of mitochondria-specific delivery.

Vesicular IFN-γ as a cooperative attacker to enhance anti-cancer effect of 5-fluorouracil via thymidine phosphorylase upregulation and tumor microenvironment normalization

On the basis of immuno-modulating effect and upregulating the activity of thymidine phosphorylase (TP), interferon-γ (IFN-γ) as a cooperative attacker was explored to enhance the anticancer activity of 5-fluorouracil (5-FU). We designed and prepared a self-assembled nano-vesicular system IFN-γ-EDP formulated by amphiphilic poly((polyethylene glycol)(dodecylphosphoethanolamine)phosphazene) (EDP) to entrap IFN-γ in the hydrophilic cavity. The IFN-γ-EDP vesicles allowed IFN-γ to accumulate at the tumor site and be taken up by tumor cells, resulting in significantly upregulated expression level of TP, distinct inhibition of cell growth, more cellular apoptosis and more serious cell cycle arrest when administrated combined with 5-FU. Moreover, IFN-γ-EDP could normalize the tumor microenvironment by enhancing the CD4⁺ and CD8⁺ T cell populations, promoting the IL-12 secretion and suppressing the IL-10 secretion in tumor. As a consequence, the combination therapy of IFN-γ-EDP with 5-FU achieved remarkably enhanced tumor inhibition rate of 56.9% against CT26 colorectal cancer.

Improved intestinal absorption and oral bioavailability of astaxanthin using poly (ethylene glycol)-graft-chitosan nanoparticles: preparation, in vitro evaluation, and pharmacokinetics in rats

BACKGROUND

Astaxanthin (ASTA) is a kind of food-derived active ingredient (FDAI) with antioxidant and antidiabetic functions. It is nontoxic but its poor solubility and low bioavailability hinder its application in the food industry. In this study, a novel carrier, polyethylene glycol-grafted chitosan (PEG-g-CS) was applied to enhance the bioavailability of astaxanthin. It encapsulated astaxanthin completely by solvent evaporation to manufacture astaxanthin using poly (ethylene glycol)-graft-chitosan nanoparticles (ASTA-PEG-g-CS) nanoparticles to improve absorption.

RESULTS

The ASTA-PEG-g-CS nanoparticles were spherical, with a particle size below 200 nm and a ζ potential of about -26 mV. Polyethylene glycol-grafted chitosan can encapsulate astaxanthin well, and the encapsulated astaxanthin was released rapidly - in 15 min in an in vitro release study. In a rat single-pass intestinal perfusion study, a low concentration of ASTA-PEG-g-CS nanoparticle (0.2 μg mL^-1 ) was better absorbed in the intestine. In particular, the jejunum could absorb most astaxanthin without a change in the concentration. An in vivo release study also demonstrated that ASTA-PEG-g-CS nanoparticles enhanced oral bioavailability significantly.

CONCLUSION

This novel carrier, PEG-g-CS, provided a simple way to encapsulate food, which improved the bioavailability of hydrophobic ingredients. © 2021 Society of Chemical Industry.

Recent advances in nanoplatforms for the treatment of neuropathic pain

STUDY DESIGN

Narrative review.

OBJECTIVES

The objective was to summarize the literature on nanoplatforms in spinal cord injury (SCI) and describe their effect in facilitating experiments for SCI. Currently, the primary clinical treatment for neuropathic pain (NP) is drug therapy, but these traditional drugs have many disadvantages, such as high dose, rapid clearance from the circulatory system, off-target side effects, and cytotoxicity. Moreover, the treatment for NP is complicated by the existence of blood-brain barrier. In recent years, nanomedicine has been receiving increased attention; this novel modality could help deliver drugs to treat NP via nanoplatforms, making it a promising alternative therapy. The use of nanoplatforms can enhance pharmaceutic effectiveness by either avoiding rapid clearance from the blood or ensuring adequate concentration in the lesion.

METHODS

A literature review was conducted, with a focus on nanoplatforms that have been described in the experimental studies of neuropathic pain.

RESULTS

We provide a brief description of the roles of liposomes, polymeric nanoparticles, metal nanoparticles, micelles, and dendrimers in the treatment of NP and discuss the prospective development of the nanoplatform system for NP.

CONCLUSION

The emergence of various nanoplatform drug delivery systems can provide an advantageous resource tool for real-time diagnosis and effective treatment of SCI-related NP.

Medicinal plants used against hepatic disorders in Bangladesh: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Liver disease is a major cause of illness and death worldwide which accounts for approximately 2 million deaths per year worldwide, 1 million due to complications of cirrhosis and 1 million due to viral hepatitis and hepatocellular carcinoma. That's why it is seeking the researchers' attention to find out the effective treatment strategies. Phytochemicals from natural resources are the main leads for the development of noble hepatoprotective drugs. The majority of the natural sources whose active compounds are currently employed actually have an ethnomedical use. Ethnopharmacological research is essential for the development of these bioactive compounds. These studies not only provide scientific evidence on medicinal plants utilized for particular therapeutic purposes, but they also ensure cultural heritage preservation. Plenty of experimental studies have been well-documented that the ethnomedicinal plants are of therapeutics' interest for the advanced pharmacological intervention in terms of hepatic disorders.

AIM OF THE STUDY

This study summarizes the processes of hepatotoxicity induced by various toxins and explores identified hepatoprotective plants and their phytoconstituents, which can guide the extraction of novel phytochemical constituents from plants to treat liver injury. This review aimed to summarize the hepatoprotective activity of Bangladeshi medicinal plants where the bioactive compounds may be leads for the drug discovery in future.

MATERIALS AND METHODS

Literature searches in electronic databases, such as Web of Science, Science Direct, SpringerLink, PubMed, Google Scholar, Semantic Scholar, Scopus, BanglaJOL, and so on, were performed using the keywords 'Bangladesh', 'ethnomedicinal plants', 'Hepatoprotective agents' as for primary searches, and secondary search terms were used as follows, either alone or in combination: traditional medicine, medicinal plants, folk medicine, liver, hepatitis, therapeutic uses, and anti-inflammatory. Besides, several books, including the book entitled "Medicinal plants of Bangladesh: chemical constituents and uses" authored by Abdul Ghani, were carefully considered, which contained pharmacological properties and phytoconstituents of many medicinal plants growing and traditionally available in Bangladesh. Among them, the most promising plant species with their latest therapeutic effects against hepatic disorders were deeply considered in this review.

RESULTS

The results of this study revealed that in most cases, therapy using plant extracts stabilized altered hepatic biochemical markers induced by hepatotoxins. Initially, we investigated 32 plant species for hepatoprotective activity, however after extensive literature searching; we observed that 20 plants offer good pharmacological evidence of hepatoprotective function. Consequently, most bioactive compounds derived from the herbs including berberine, thymoquinone, andrographolide, ursolic acid, luteolin, naringenin, genistein, quercetin, troxerutin, morin, epigallocatechin-3-gallate, chlorogenic acid, emodin, curcumin, resveratrol, capsaicin, ellagic acid, etc. are appeared to be effective against hepatic disorders.

CONCLUSIONS

Flavonoids, phenolic acids, monoterpenoids, diterpenoids, triterpenoids, alkaloids, chromenes, capsaicinoids, curcuminoids, and anthraquinones are among the phytoconstituents were appraised to have hepatoprotective activities. All the actions displayed by these ethnomedicinal plants could make them serve as leads in the formulation of drugs with higher efficacy to treat hepatic disorders.

Preparation, Characterization, and Anticancer Effects of Capsaicin-Loaded Nanoliposomes

BACKGROUND

Medicinal plants have proven their value as a source of molecules with therapeutic potential, and recent studies have shown that capsaicin has profound anticancer effects in several types of human cancers. However, its clinical use is handicapped due to its poor pharmacokinetics. This study aims to enhance capsaicin's pharmacokinetic properties by loading the molecule into nanoliposomes model and testing its anticancer activity.

METHODS

Nanoliposomes were prepared using the thin-film method, and characteristics were examined followed by qualitative and quantitative analyses of encapsulation efficiency and drug loading using HPLC at different lipid/capsaicin ratios. Cell viability assay (MTT) was used to determine IC50.

RESULTS

Capsaicin-loaded nanoliposomes showed optimum characteristics of morphology, particle size, zeta potential, and stability. In vitro anticancer activity of capsaicin and capsaicin-loaded nanoliposomes were compared against MCF7, MDA-MB-231, K562, PANC1, and A375 cell lines. Capsaicin-loaded nanoliposomes showed significant improvement in anticancer activity against cancers cell lines studied (p < 0.001), with increased selectivity against cancer cells compared to capsaicin.

CONCLUSION

The encapsulated capsaicin nanoliposomes produced an improvement in pharmacokinetics properties, enhancing the anticancer activity and selectivity compared with capsaicin. This model seems to offer a potential for developing capsaicin formulations for the prevention and treatment of cancer.

Applications of capsaicin in food industry: functionality, utilization and stabilization

As a bioactive component in Capsicum species, capsaicin is a compound of hot chili peppers which is known as the main substance responsible for the spiciness of these fruits. Besides its taste and physiological effects, it exhibits good antioxidant activity in food matrix and antimicrobial activity against foodborne pathogens and viruses. Considering its low stability and bioaccessibility, and also regarding its irritation, the entrapment methods of capsaicin are fully developed. To compensate the limitations of capsaicin, various encapsulation methods have been used so far, including coacervation, emulsion, spray chilling, and liposomal delivery. Capsaicin has been widely used as a flavoring and preservative agent in food formulations and even as an active compound in packaging film and functional foods. This review provides an overview of the techno-functional properties, stabilization procedures, and burgeoning usages of capsaicin in the latest studies of the food sector. So, it may introduce new windows for the application of this compound.

In vitro dissolution considerations associated with nano drug delivery systems

Nano drug delivery systems (NDDS) offer promising solution for the translation of future nanomedicines. As bioavailability and therapeutic outcomes can be improved by altering the drug release from these NDDS, it becomes essential to thoroughly understand their drug release kinetics. Moreover, U.S. Food and Drug Administration requires critical evaluation of potential safety, efficacy, and public health impacts of nanomaterials. Spiraling up market share of NDDS has also stimulated the pharmaceutical industry to develop their cost-effective generic versions after the expiry of patent and associated exclusivity. However, unlike the conventional dosage forms, the in vivo disposition of NDDS is highly intricate and different from their in vitro behavior. Significant challenges exist in the establishment of in vitro-in vivo correlation (IVIVC) due to incomplete understanding of nanoparticles' in vivo biofate and its impact on in vitro experimental protocols. A rational design of dissolution may serve as quality and quantity control tool and help develop a meaningful IVIVC for favorable economic implications. Clinically relevant drug product specifications (critical quality attributes) can be identified by establishing a link between in vitro performance and in vivo exposure. In vitro dissolution may also play a pivotal role to understand the dissolution-mediated clearance and safety of NDDS. Prevalent in vitro dissolution methods for NDDS and their limitations are discussed in this review, among which USP 4 is gaining more interest recently. Researchers are working diligently to develop biorelevant in vitro release assays to ensure optimal therapeutic performance of generic versions of these NDDS. This article focuses on these studies and presents important considerations for the future development of clinically relevant in vitro release methods. This article is categorized under: Toxicology and Regulatory Issues in Nanomedicine > Regulatory and Policy Issues in Nanomedicine.

Carboxymethyl chitosan coated medium-chain fatty acid nanoliposomes: structure, composition, stability and in vitro release investigation

Medium-chain fatty acids (MCFAs) have been proven as an easy energy source and active ingredient to prevent obesity and other metabolic disorders. However, the inherent hydrophobic nature of MCFAs causes poor aqueous solubility and dissolution in the gastrointestinal (GI) tract, thus limiting their applications in aqueous foods. To address these issues, a nutraceutical carrier system was developed by coating nanoliposomes with carboxymethyl chitosan (CMCS) through a series of well-designed processes, including thin-film hydration, dynamic high pressure microfluidization (DHPM) and surface modification. Electron microscopy investigation reveals an obvious morphology evolution from the uncoated nanoliposomes (UC-LPs) to the final CMCS coated nanoliposomes (CMCS-LPs). Together with the FTIR results, it confirms the successful coating of CMCS. More importantly, the resultant CMCS-LPs have a more negatively charged surface with a ζ-potential value of around -18.5 mV, which helps to increase the stability by avoiding severe particle aggregation. Owing to the above benefits, the encapsulated MCFAs can be safely retained in a long storage period of 90 days at 4 °C and the new carrier system also exhibits a more sustained release of MCFAs in the GI fluid.

Improved oral bioavailability, cellular uptake, and cytotoxic activity of zingerone via nano-micelles drug delivery system

Herein, a nano-micelle drug delivery system was developed to orally improved zingerone's bioavailability and its antitumor effect. Indeed, zingerone-loaded d-α-tocopheryl polyethylene glycol succinate micelles (ZTMs) were effectively prepared, characterised and assessed. The ZTMs had diameter, polydispersity index, and zeta potential of 50.62 ± 0.25 nm, 0.168 ± 0.006, and -28.07 ± 0.33 mV, respectively, coupled with a high entrapment efficiency (m/m, %) were 94.71 ± 2.02. The release rate of ZTMs in three media was significantly greater than that of free zingerone. Intriguingly, results obtained from pharmacokinetic studies showed that the oral bioavailability of the ZTMs was enhanced by 5.10 times in comparison with the free zingerone. Further, the half inhibitory concentration (IC50) of ZTMs and free zingerone was 7.56 μg/ml and 14.30 μg/ml, respectively, on HepG2 cells. Hence, ZTMs may be used as a potential approach to enrich the solubility, bioavailability, and concomitant anti-proliferative effect of zingerone in vitro.

Bioavailability of a Capsaicin Lipid Multi-particulate Formulation in Rats

Background and Objective

Because of the stomach-burning sensation it induces, capsaicin has been used at relatively low doses as a nutritional supplement, which has limited its bioavailability. The objective of this study was to investigate the serum bioavailability of capsaicin supplementation with or without a lipid multi-particulate (LMP) formulation.

Methods

Thirty-five rats were divided into five groups and administered capsaicin at either 0.2 or 1 mg/kg with or without the LMP formulation. Capsaicin bioavailability was assessed based on the area under the concentation–time curve (AUC), the time to peak concentration (T_max), and the peak serum concentration (C_max).

Results

For each formulation, the capsaicin C_max was reached at 90 min and decreased thereafter. Serum capsaicin concentrations were greater in rats administered the higher dose of capsaicin (1 mg/kg) in the LMP formulation at all measurement times (P  ≤ 0.05). The AUC showed a significant increase, about 20%, when capsaicin was administered in the LMP formulation at the high dose (P  = 0.002). The T_max for oral capsaicin was similar whether or not administration was via the LMP formulation (P  = 0.163). However, the C_max of capsaicin increased in a dose-dependent manner (P  < 0.05). Although the LMP formulation of the high dose of capsaicin resulted in a numerically higher C_max, it was not statistically significantly higher (P  = 0.068).

Conclusions

The present work demonstrated that administration of capsaicin via the LMP formulation significantly impacted the pharmacokinetic parameters and the serum bioavailability of orally administered 1 mg/kg capsaicin in rats. The bioavailability of capsaicin in humans may also be increased by using the LMP formulation.

Loading of capsaicin-in-cyclodextrin inclusion complexes into PEGylated liposomes and the inhibitory effect on IL-8 production by MDA-MB-231 and A549 cancer cell lines

Capsaicin (CAP) is an active component in Capsicum annuum L. known to have anti inflammatory and anticancer activity. CAP is highly lipophilic and suffers low bioavailability. Therefore, developing delivery systems that enhance solubility and bioavailability can provide more promising therapeutic applications for CAP. In the current work, CAP was complexed with β-cyclodextrin (βCD) to form capsaicin-in-β-cyclodextrin (CAP-in-βCD) inclusion complexes. Then, the CAP-in-βCD inclusion complexes were characterized and loaded into PEGylated liposomes using the thin-film hydration extrusion method. The size, charge, and polydispersity index (PDI) of the PEGylated liposomes were characterized. The levels of IL-8 production were quantified after treatment using array beads. The results of this work showed that the successful formation of inclusion complexes at 1:5 M ratio of CAP to βCD respectively. PEGylated liposomes loaded with βCD/CAP inclusion complexes (CAP-in-βCD-in-liposomes) have a hydrodynamic diameter of (181 ± 36) nm, zeta potential of (-2.63 ± 4.00) mV, encapsulation efficiency (EE) of (38.65 ± 3.70)%, drug loading (DL) of (1.65 ± 0.16)%, and a stable release profile. Both free CAP and liposomal CAP showed a significant reduction in the IL-8 production by the MDA-MB-231 and A549 cancer cell lines after treatment. In conclusion, a liposomal-based drug delivery system for CAP was achieved.

Meloxicam emulgels for topical management of rheumatism: Formulation development, in vitro and in vivo characterization

Purpose

The study designed, formulated and evaluated meloxicam emulgels as a potential alternative topical treatment option for rheumatism.

Methods

A 3² factorial design was employed to formulate nine preliminary meloxicam emulgels (Formulations F1 - F9). The influences of carbopol-934 and menthol as gelling agent and drug release enhancer, respectively, were correlated with four pharmaceutical properties of the formulated emulgels namely viscosity, spreadability, and cumulative drug release at one hour and at eight hours. Using the generated data and applying the Design Expert® modelling software, two optimized meloxicam emulgels (Formulations F10 and F11) were designed, formulated and evaluated. In vivo anti-inflammatory efficacy was conducted using carrageenan-induced rat paw oedema method. Drug release kinetics was modelled using DDSolver® dissolution software.

Results

All formulations were homogenous with no observable grittiness or phase separation. The optimized Formulations F10 and F11 had pH 6.5 and 6.4, viscosity of 23656 and 24524 mPa.s, spreadability of 9.9 and 9.5 cm, and drug content of 90.4% and 92.9%, respectively, all within optimal values. The cumulative percentage of drug released was 21.0% and 22.9% after one hour and 50.1% and 55.8% after eight hours for Formulations F10 and F11, respectively. Drug release kinetics exhibited Fickian diffusion best described by Korsmeyer-Peppas model. Paw volume inhibition by Formulation F11 at two and three hours after carrageenan injection was statistically significant (p < 0.05).

Conclusion

The optimized meloxicam emulgels had high pharmaceutical quality and were pharmacologically active. Further optimization could potentially provide a safe and efficacious alternative treatment option for rheumatism.

Naringenin Nano-Delivery Systems and Their Therapeutic Applications

Naringenin (NRG) is a polyphenolic phytochemical belonging to the class of flavanones and is widely distributed in citrus fruits and some other fruits such as bergamot, tomatoes, cocoa, and cherries. NRG presents several interesting pharmacological properties, such as anti-cancer, anti-oxidant, and anti-inflammatory activities. However, the therapeutic potential of NRG is hampered due to its hydrophobic nature, which leads to poor bioavailability. Here, we review a wide range of nanocarriers that have been used as delivery systems for NRG, including polymeric nanoparticles, micelles, liposomes, solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), nanosuspensions, and nanoemulsions. These nanomedicine formulations of NRG have been applied as a potential treatment for several diseases, using a wide range of in vitro, ex vivo, and in vivo models and different routes of administration. From this review, it can be concluded that NRG is a potential therapeutic option for the treatment of various diseases such as cancer, neurological disorders, liver diseases, ocular disorders, inflammatory diseases, skin diseases, and diabetes when formulated in the appropriate nanocarriers.

Effect of capsaicin on the protozoan parasite Trypanosoma cruzi

Trypanosoma cruzi is the causative agent of Chagas disease. There are only two approved treatments, both of them unsuitable for the chronic phase, therefore the development of new drugs is a priority. Trypanosoma cruzi arginine kinase (TcAK) is a promising drug target since it is absent in humans and it is involved in cellular stress responses. In a previous study, possible TcAK inhibitors were identified through computer simulations resulting the best compounds capsaicin and cyanidin derivatives. Here, we evaluate the effect of capsaicin on TcAK activity and its trypanocidal effect. Although capsaicin produced a weak enzyme inhibition, it had a strong trypanocidal effect on epimastigotes and trypomastigotes (IC50 = 6.26 µM and 0.26 µM, respectively) being 20-fold more active on trypomastigotes than mammalian cells. Capsaicin was also active on the intracellular cycle reducing by half the burst of trypomastigotes at approximately 2 µM. Considering the difference between the concentrations at which parasite death and TcAK inhibition occur, other possible targets were predicted. Capsaicin is a selective trypanocidal agent active in nanomolar concentrations, with an IC50 57-fold lower than benznidazole, the drug currently used for treating Chagas disease.

Capsaicin Loaded Solid SNEDDS for Enhanced Bioavailability and Anticancer Activity: In-Vitro, In-Silico, and In-Vivo Characterization

In this investigation, the fabrication of capsaicin loaded self nano emulsifying drug delivery system (SNEDDS) was attempted to improve the effectiveness of capsaicin through the oral route. A pseudo-ternary phase diagram was constructed at different km values (1:1, 2:1, & 3:1). Nine liquid formulations (L-CAP-1 to L-CAP-9) were prepared at km = 3, evaluated & converted to solid free-flowing granules using neusilin® US2. L-CAP-3 comprising of 15% isopropyl myristate, 33.75% Labrafil, & 11.25% ethanol exhibited higher % transmittance (98.90 ± 1.24%) & lower self-emulsification time (18.19 ± 0.46 s). FT-IR spectra showed no incompatibility whereas virtual analysis confirmed hydrogen bond interaction between amino hydrogen in the capsaicin & oxygen of the neusilin. DSC & XRD study revealed the amorphization & molecular dispersion of capsaicin in S-SNEDDS. TEM analysis confirmed the nano-sized spherical globules. Within 15 min, L-SNEDDS, S-SNEDDS, & pure capsaicin showed 87.36 ± 3.25%, 85.19 ± 4.87%, & 16.61 ± 3.64% drug release respectively. S-CAP-3 significantly (P < 0.001) inhibited the proliferation of HT-29 colorectal cancer cells than capsaicin. Apoptosis assay involving Annexin V/PI staining for S-CAP-3 treated cells demonstrated a significant (P < 0.001) apoptotic rate. Remarkably, 3.6 fold increase in bioavailability was observed after oral administration of capsaicin-SNEDDS than plain capsaicin.

Engineered Site-specific Vesicular Systems for Colonic Delivery: Trends and Implications

Steering drug-loaded, site-specific, coated lipid vesicles to the target receptor sites have the potential of plummeting adverse effects and improving the pharmacological response in diverse pathologies of the large bowel, especially the colon. Colonic delivery via oral route has its own challenges, often governed by several glitches such as drug degradation or absorption in the upper GIT, instability of proteins/peptides due to high molecular weight, and peptidase activity in the stomach. Consequently, colon-specific coated liposomal systems (CSLS) offer a potential alternate for not only site-specificity, but protection from proteolytic activity, and prolonged residence time for greater systemic bioavailability. On the other hand, liposomal delivery via the oral route is also cumbersome owing to several barriers such as instability in GIT, difficulty in crossing membranes, and issues related to production at the pilot scale. New advancements in the field of CSLS have successfully improved the stability and permeability of liposomes for oral delivery via modulating the compositions of lipid bilayers, adding polymers or ligands. Despite this ostensible propitiousness, no commercial oral CSLS has advanced from bench to bedside for targeted delivery to the colon as yet. Nevertheless, CSLS has quite fascinated the manufacturers owing to its potential industrial viability, simplistic and low-cost design. Hence, this review aims to decipher the convolutions involved in the engineering process of industrially viable CSLS for colonic delivery.

Combinatorial Library of Cyclic Benzylidene Acetal-Containing pH-Responsive Lipidoid Nanoparticles for Intracellular mRNA Delivery

Lipidoid nanoparticles have been demonstrated to be effective for intracellular delivery of small molecule drugs, proteins, and nucleic acids. Stimuli-responsive lipidoid nanoparticles are able to further improve delivery efficacy and reduce carrier-induced toxicity. Our group previously developed reduction and photoresponsive combinatorial libraries of lipidoid nanoparticles for small molecule and biologics delivery. Herein, we describe the synthesis, characterization, and intracellular mRNA delivery application of a new library of pH-responsive lipidoid nanoparticles. The acid-degradable cyclic benzylidene acetal-containing cationic lipidoids (R-O16CBA) were synthesized through a multistep reaction and characterized by NMR and MS. The acid-triggered degradation of lipidoids was studied using NMR, MS, DLS, and TEM. The results revealed that the R-O16CBA lipidoid can be completely degraded at pH 5. The R-O16CBA lipidoid nanoparticles were then fabricated with different formulations of DOPE and cholesterol and tested in vitro for intracellular mRNA delivery.

Pharmacokinetics and Metabolism of Liposome-Encapsulated 2,4,6-Trihydroxygeranylacetophenone in Rats Using High-Resolution Orbitrap Liquid Chromatography Mass Spectrometry

2,4,6-trihydroxy-3-geranylacetophenone (tHGA) is a bioactive compound that shows excellent anti-inflammatory properties. However, its pharmacokinetics and metabolism have yet to be evaluated. In this study, a sensitive LC-HRMS method was developed and validated to quantify tHGA in rat plasma. The method showed good linearity (0.5–80 ng/mL). The accuracy and precision were within 10%. Pharmacokinetic investigations were performed on three groups of six rats. The first two groups were given oral administrations of unformulated and liposome-encapsulated tHGA, respectively, while the third group received intraperitoneal administration of liposome-encapsulated tHGA. The maximum concentration (C_max), the time required to reach C_max (t_max), elimination half-life (t_1/2) and area under curve (AUC_0–24) values for intraperitoneal administration were 54.6 ng/mL, 1.5 h, 6.7 h, and 193.9 ng/mL·h, respectively. For the oral administration of unformulated and formulated tHGA, C_max values were 5.4 and 14.5 ng/mL, t_max values were 0.25 h for both, t_1/2 values were 6.9 and 6.6 h, and AUC_0–24 values were 17.6 and 40.7 ng/mL·h, respectively. The liposomal formulation improved the relative oral bioavailability of tHGA from 9.1% to 21.0% which was a 2.3-fold increment. Further, a total of 12 metabolites were detected and structurally characterized. The metabolites were mainly products of oxidation and glucuronide conjugation.

The Effect of Natural Antioxidants in the Development of Metabolic Syndrome: Focus on Bergamot Polyphenolic Fraction

Metabolic syndrome (MetS) represents a set of clinical findings that include visceral adiposity, insulin-resistance, high triglycerides (TG), low high-density lipoprotein cholesterol (HDL-C) levels and hypertension, which is linked to an increased risk of developing type 2 diabetes mellitus (T2DM) and atherosclerotic cardiovascular disease (ASCVD). The pathogenesis of MetS involves both genetic and acquired factors triggering oxidative stress, cellular dysfunction and systemic inflammation process mainly responsible for the pathophysiological mechanism. In recent years, MetS has gained importance due to the exponential increase in obesity worldwide. However, at present, it remains underdiagnosed and undertreated. The present review will summarize the pathogenesis of MetS and the existing pharmacological therapies currently used and focus attention on the beneficial effects of natural compounds to reduce the risk and progression of MetS. In this regard, emerging evidence suggests a potential protective role of bergamot extracts, in particular bergamot flavonoids, in the management of different features of MetS, due to their pleiotropic anti-oxidative, anti-inflammatory and lipid-lowering effects.

Fabrication of capsaicin emulsions: improving the stability of the system and relieving the irritation to the gastrointestinal tract of rats

BACKGROUND

Capsaicin, as a major pungent ingredient of peppers, has many health benefits. However, the strong irritation effect of capsaicin inhibits its application in the food industry. Emulsions can be an effective approach to alleviate the irritation.

RESULTS

In this study, we used tocopheryl polyethylene glycol 1000 succinate (TPGS) as an emulsifier to prepare capsaicin emulsions through high-pressure homogenization. Capsaicin emulsions with a particle size of about 100 nm, -36.4 mV zeta potential, and 91.9% encapsulation efficiency were prepared successfully and showed better environmental stability and higher antioxidant activity. Emulsions reduced the cumulative release of capsaicin and had no toxic effect on buffalo rat liver (BRL-3A) cells. Moreover, the gastrointestinal injury model of rats showed that emulsions reduced the strong irritation of capsaicin.

CONCLUSION

This work provides a theoretical basis for the application of irritant ingredients in food industry. © 2019 Society of Chemical Industry.

Capsaicin—the major bioactive ingredient of chili peppers: bio-efficacy and delivery systems

The mechanisms of bio-efficacy of capsaicin and delivery systems with enhanced bioavailability were reviewed.

The Molecular Effects of Sulforaphane and Capsaicin on Metabolism upon Androgen and Tip60 Activation of Androgen Receptor

Androgen receptor (AR) stimulators, such as androgen and Tip60, play a pivotal role in prostatic carcinogenesis as androgen receptor signaling is critical for the growth and transformation of the prostate gland. Moreover, androgen and Tip60 promotes HIF-1α activation, involved in metabolic reprogramming by increasing glycolysis, a hallmark in cancer initiation and development. In this study we evaluated the effect of androgen and Tip60 stimulus in AR pathway activation and HIF-1α stabilization, in terms of proliferation and cell metabolism in androgen-sensitive LNCaP cells. The protective role of the bioactive compounds sulforaphane and capsaicin against the effect of these stimuli leading to pro-carcinogenic features was also addressed. Sulforaphane and capsaicin decreased nuclear AR, prostate specific antigen and Bcl-XL levels, and cell proliferation induced by androgen and Tip60 in LNCaP cells. These bioactive compounds prevented the increase in glycolysis, hexokinase and pyruvate kinase activity, and reduced HIF-1α stabilization induced by androgen and Tip60 in LNCaP cells. The protective role of sulforaphane and capsaicin on prostate cancer may rely on mechanisms involving the inhibition of Tip60, AR and HIF-1α effects.

Curcumin diethyl disuccinate, a prodrug of curcumin, enhances anti-proliferative effect of curcumin against HepG2 cells via apoptosis induction

Curcumin (Cur) has been reported to have anti-hepatocellular carcinoma activity but its poor oral bioavailability limits its further development as a chemotherapeutic agent. We synthesized previously a succinate ester prodrug of Cur, curcumin diethyl disuccinate (CurDD) with better chemical stability in a buffer solution pH 7.4. Here, we further investigated and compared the cellular transport and anti-proliferative activity against HepG2 cells of CurDD and Cur. Transport of CurDD across the Caco-2 monolayers provided a significantly higher amount of the bioavailable fraction (BF) of Cur with better cytotoxicity against HepG2 cells compared to that of Cur (p < 0.05). Flow cytometric analysis showed that the BF of CurDD shifted the cell fate to early and late apoptosis to a higher extent than that of Cur. The Western blot analysis revealed that CurDD increased Bax protein expression, downregulated Bcl-2 protein, activated caspase-3 and -9 and increased LC3-II protein level in HepG2 cells. Flow cytometric and immunoblotting results suggest that CurDD can induce HepG2 cell death via an apoptotic pathway. We suggest that CurDD can overcome the limitations of Cur in terms of cellular transport with a potential for further extensive in vitro and in vivo studies of anti-hepatocellular carcinoma effects.

A Novel Micron-Size Particulate Formulation of Felodipine with Improved Release and Enhanced Oral Bioavailability Fabricated by Coaxial Electrospray

The antihypertensive drug felodipine (FD) is a typical biopharmaceutics classification system (BCS) II drug; thus, improving the dissolution rate of FD is very important to enhance its bioavailability. Besides, according to the in situ "close loop" perfusion assay, we found that the jejunum is the main absorptive site, then the duodenum and ileum. Consequently, a novel micron-size particulate of FD in a core-shell structure was fabricated by a coaxial electrospray technique; within the drug delivery system, Hypromellose K4M (HPMC K4M) was selected as a sheath material to prolong the retention time in the upper GI tract, while povidone K30 (PVP K30) was mixed with FD in the inner layer. The dissolution study in three different media (0.02% Tween-80 solution; phosphate buffer containing 0.02% Tween-80, pH 6.8; and HCl solution containing 0.02% Tween-80, pH 1.2) demonstrated that FD-loaded coaxial electrospray particles (F-COES) could greatly improve the dissolution of FD. Furthermore, in vivo pharmacokinetics revealed that F-COES emerged no changes in the half-life but significantly prolonged the t_max and increased the oral bioavailability. Collectively, this work supplies a promising drug release system that will improve the dissolution and enhance the bioavailability simultaneously for those poorly water-soluble drugs mainly absorbed in the upper GI tract.