A novel nanosuspension of andrographolide: Preparation, characterization and passive liver target evaluation in rats

Quality by design optimization of formulation variables and process parameters for enhanced transdermal delivery of nanosuspension

This investigation aims to fabricate, characterize, and optimize organogel containing andrographolide nanosuspension to enhance transdermal drug delivery into and across the skin in vitro. We identified the critical material attributes (CMAs) and critical process parameters (CPPs) that impact key characteristics of andrographolide nanosuspension using a systematic quality-by-design approach. We prepared andrographolide nanosuspension using the wet milling technique and evaluated various properties of the formulations. The CMAs were types and concentrations of polymers, types and concentrations of surfactants, drug concentration, and lipid concentration. The CPPs were volume of milling media and milling duration. Mean particle size, polydispersity index, encapsulation efficiency, and drug loading capacity as critical quality attributes were selected in the design for the evaluation and optimization of the formulations. Furthermore, we developed and evaluated organogel formulation to carry andrographolide nanosuspension 0.05% w/w. Drug release and permeation studies were conducted to assess the drug release kinetics and transdermal delivery of andrographolide. We presented the alteration in the average particle size, polydispersity index, encapsulation efficiency, drug-loading capacity, and drug release among various formulations to select the optimal parameters. The permeation study indicated that organogel delivered markedly more drug into the receptor fluid and skin tissue than DMSO gel (n = 3, p < 0.05). This enhancement in transdermal drug delivery was demonstrated by cumulative drug permeation after 24 h, steady-state flux, permeability coefficient, and predicted steady-state plasma concentration. Drug quantity in skin layers, total delivery, delivery efficiency, and topical selectivity were also reported. Conclusively, andrographolide nanosuspension-loaded organogel significantly increased transdermal drug delivery in vitro.

Preparation and characterization of andrographolide nano-cocrystals using hummer acoustic resonance technology

Andrographolide (AG) is a diterpene lactone with significant anti-inflammatory and antitumor activities. However, the poor water solubility limits its clinical application. An andrographolide-salicylic acid (AG-SLA) nano-cocrystal delivery system was rapidly developed using hummer acoustic resonance (HAR) technology in this research. The formulation of the AG-SLA nano-cocrystal suspension and the process parameters for HAR technology were optimized in a high-throughput manner, with SDS-Tween 80 as the optimal composite stabilizer. Nano-cocrystal suspension of AG-SLA with an average particle size of 190 nm were successfully prepared, and then the optimal formulation were tenfold scaled up. Freeze-drying was adopted to solidify the nano-cocrystal and improve its stability. Various analytical techniques were used to characterize the particle size and solid state of the nano-cocrystals. The high-energy input from the HAR instrument induced partial amorphization of the nano-cocrystals, as confirmed by PXRD and DSC analyses. Saturation solubility experiments demonstrated that the solubility in pH 1.2 hydrochloric acid buffer and pH 6.8 phosphate buffer increased by 5.74 times and 6.82 times, respectively, compared to raw AG. In vitro dissolution tests indicated that the cumulative release over 120 min in pH 1.2 hydrochloric acid buffer and pH 6.8 phosphate buffer increased by 1.60 times and 1.88 times, respectively, compared to raw AG.

Acoustic resonance technology and quality by design approach facilitate the development of the robust tetrandrine nano-delivery system

The aim of this study was to develop a sufficiently robust tetrandrine (Tet) nano-delivery system using acoustic resonance (AR) technology and freeze-drying technology. This system can effectively improve the solubility and dissolution properties of Tet, along with high stability and scale-up adaptability. Firstly, 54 stabilizers were screened simultaneously in a high-throughput manner with the help of AR technology to fully explore the optimal prescription space of tetrandrine nanosuspension (Tet-NS). The Plackett-Burman design was used to screen for critical variables severely affecting the quality of Tet-NS. The Box-Behnken design was used to investigate and optimize critical variables to obtain optimal nanosuspensions. The optimal prescription was successfully scaled up by 100 times, which was the initial exploration of its commercial scale production. Solidification studies have shown that formulations with 2.44% fructose as the cryoprotectant have excellent redispersibility. Compared with pure Tet, Tet in Tet-NS showed a significant increase in solubility and dissolution rate in water. Fourier transform infrared (FT-IR) demonstrated that no significant interactions occurred between the drug and excipients in Tet-NS. Powder x-ray diffraction analysis (PXRD) indicated that some of the Tet transformed into amorphous state during the preparation process. In short-term stability study, Tet-NS successfully maintained its physical stability. In summary, under the guidance of the QbD concept, this study rapidly developed Tet-NS using acoustic resonance technology, which can effectively improve the solubility and dissolution properties of Tet. During the development of Tet-NS, AR technology has demonstrated high particle size reduction capability, the ability to process multiple sets of formulations in parallel, and excellent scale-up capability. Meanwhile, the method and concept of this study are not limited to Tet, but also applicable to other poorly water-soluble drugs.

High-throughput preparation, scale up and solidification of andrographolide nanosuspension using hummer acoustic resonance technology

The aim of this study was to rapidly develop a sufficiently robust andrographolide nanosuspension (AG-NS) system using hummer acoustic resonance (HAR) technology. The system can effectively improve the dissolution properties of AG, while having high stability and scale-up adaptability. The formulation of AG-NS was optimized in a high-throughput manner using HAR technology and the preparation process was optimized stepwise. Optimal AG-NS with Z-Ave = 223.99 ± 3.16 nm, PDI=0.095 ± 0.007 and zeta potential = -33.20 ± 0.58 mV was successfully prepared with Polyvinylpyrrolidone K30 and Sodium dodecyl sulfate. The optimal prescription was successfully scaled up 100 and 150 times using HAR technology, which was the initial exploration of its commercial scale production. AG-NS was solidified using freeze drying and fluid bed technology, respectively. The optimal AG-NS and its solidified products were exhaustively characterized using various analytical techniques. The high energy input of HAR technology and drying process converted part of the drug into the amorphous state. The in-vitro drug dissolution studies demonstrated relatively higher drug dissolution for AG-NS and its solidified products compared to controls at both the dissolution media (pH 1.2 buffer and pH 6.8 buffer). AG-NS and its solidified products successfully maintained their physical stability in short-term stability and accelerated stability experiments, respectively.

Nanosuspensions technology as a master key for nature products drug delivery and In vivo fate

The drug nanosuspensions is a universal formulation approach for improved drug delivery of hydrophobic drugs and one the most promising approaches for increasing the biopharmaceutical performance of poorly water-soluble drug substances, especially for nature products. This review aimed to summarize the nanosuspensions preparation approaches and the main technological difficulties encountered in nanosuspensions development, such as guidelines for stabilizers screening, in vivo fate of the intravenously administrated nanosuspensions, and how to realize the intravenously target delivery was reviewed. Furthermore, challenges of nanosuspensions for the nature products delivery also was discussed and commented. Therefore, it hoped to provide reference and assistance for the nanosuspensions production, stabilizers usage, and predictability of in vivo fate and controllability of targeting delivery of the nature products nanosuspensions.

The role of Andrographolide in the prevention and treatment of liver diseases

BACKGROUND

The presence or absence of damage to the liver organ is crucial to a person's health. Nutritional disorders, alcohol consumption, and drug abuse are the main causes of liver disease. Liver transplantation is the last irrevocable option for liver disease and has become a serious economic burden worldwide. Andrographolide (AP) is one of the main active ingredients of Herba Andrographitis. It has several biological activities and has been reported to have protective and therapeutic effects against liver diseases. Earlier literature has been written on AP's role in treating inflammation and other diseases, and there has not been a systematic review on liver diseases. This review is dedicated to sorting out the research results of AP against liver diseases. Pharmacokinetics, toxicity, and nanotechnology to improve bioavailability are discussed. Finally, an outlook and assessment of its future are provided.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. PubMed and web of Science databases were used to search all relevant literature on AP for liver disease up to 2022.

RESULTS

Studies have shown that AP plays an important role in different liver disease phenotypes, mainly through anti-inflammatory and antioxidant activities. AP regulates HO-1 and inhibits hepatitis virus replication. It affects the NF-κB pathway, downregulates inflammatory factors such as IL-1β, IL-6, and TNF-α, and reduces liver damage. In preventing liver fibrosis, AP inhibits angiogenesis and activation of hepatic stellate cells and reduces oxidative stress involved in the Nrf2 and TGF-β1/Smad pathways. In addition, AP impedes the development of liver cancer by promoting apoptosis and autonomous phagocytosis in a cell-dependent way. Interestingly, miRNAs are involved in the therapeutic process of liver cancer and hepatic fibrosis. The poor solubility of AP limits the development of dosage forms. Therefore, the advent of nanoformulations has improved bioavailability. Although the effect of AP is dose- and time-dependent, the magnitude of its toxicity is not negligible. Some clinical trials have shown that AP has mild side effects.

CONCLUSIONS

AP, as an effective natural product, has a good effect on the liver disease through multiple pathways and targets. However, the dose reaches a certain level, leading to its toxicity and side effects. For better clinical application of AP, high-quality clinical and toxic intervention mechanisms are needed to validate current studies. In addition, modulation of miRNA-mediated hepatocellular carcinoma and liver fibrosis and synergistic action with drugs may be the future focus of AP. In conclusion, AP can be regarded as an important candidate for treating different liver diseases in the future.

Pharmacokinetics and Anti-Diabetic Studies of Gliclazide Nanosuspension

Gliclazide (GCZ), an antidiabetic medication, has poor solubility and limited oral bioavailability due to substantial first-pass metabolism. Thus, the purpose of the current study was to optimize and formulate a GCZ nanosuspension (NS) employing the antisolvent precipitation technique. A three-factor, three-level Box–Behnken design (BBD) was used to examine the impact of the primary formulation factors (drug concentration, stabilizer, and surfactant %) on particle size. The optimized NS contains 29.6 mg/mL drug, 0.739% lecithin, and 0.216% sodium dodecyl sulfate (SDS). Under scanning microscopy, the topography of NS revealed spherical particles. Furthermore, NS had a much better saturation solubility than the pure material, which resulted in a rapid dissolving rate, which was attributed to the amorphous structure and smaller particle size of the NS particles. Studies on intestinal permeability using the in vitro noneverted intestinal sac gut method (duodenum, jejunum, and ileum) and single-pass intestinal permeability (SPIP) techniques showed that the effective permeability was also increased by more than 3 fold. In the pharmacokinetic study, the C_max and AUC_0–t values of NS were approximately 3.35- and 1.9-fold higher than those of the raw medication and marketed formulation (MF). When compared to plain drug and commercial formulations, the antidiabetic efficacy of NS demonstrated that it had a significant impact on lowering glucose levels.

Andrographolide: A review of its pharmacology, pharmacokinetics, toxicity and clinical trials and pharmaceutical researches

Andrographis paniculata (Burm. f.) Wall. ex Nees, a renowned herb medicine in China, is broadly utilized in traditional Chinese medicine (TCM) for the treatment of cold and fever, sore throat, sore tongue, snake bite with its excellent functions of clearing heat and toxin, cooling blood and detumescence from times immemorial. Modern pharmacological research corroborates that andrographolide, the major ingredient in this traditional herb, is the fundamental material basis for its efficacy. As the main component of Andrographis paniculata (Burm. f.) Wall. ex Nees, andrographolide reveals numerous therapeutic actions, such as antiinflammatory, antioxidant, anticancer, antimicrobial, antihyperglycemic and so on. However, there are scarcely systematic summaries on the specific mechanism of disease treatment and pharmacokinetics. Moreover, it is also found that it possesses easily ignored security issues in clinical application, such as nephrotoxicity and reproductive toxicity. Thereby it should be kept a lookout over in clinical. Besides, the relationship between the efficacy and security issues of andrographolide should be investigated and evaluated scientifically. In this review, special emphasis is given to andrographolide, a multifunctional natural terpenoids, including its pharmacology, pharmacokinetics, toxicity and pharmaceutical researches. A brief overview of its clinical trials is also presented. This review intends to systematically and comprehensively summarize the current researches of andrographolide, which is of great significance for the development of andrographolide clinical products. Noteworthy, those un-cracked issues such as specific pharmacological mechanisms, security issues, as well as the bottleneck in clinical transformation, which detailed exploration and excavation are still not to be ignored before achieving integration into clinical practice. In addition, given that current extensive clinical data do not have sufficient rigor and documented details, more high-quality investigations in this field are needed to validate the efficacy and/or safety of many herbal products.

Nanoemulsomes for Enhanced Oral Bioavailability of the Anticancer Phytochemical Andrographolide: Characterization and Pharmacokinetics

Andrographolide (AG) is an antitumor phytochemical that acts against non-Hodgkin's lymphoma. However, AG shows low oral bioavailability due to extensive first-pass metabolism and P-glycoprotein efflux. Novel biocompatible lipoprotein-simulating nanosystems, emulsomes (EMLs), have gained significant attention due to their composition of natural components, in addition to being lymphotropic. Loading AG on EMLs is believed to mitigate the disadvantage of AG and enhance its lymphatic transport. This study developed a chylomicron-simulating system (EMLs) as a novel tool to overcome the AG oral delivery obstacles. Optimized EML-AG had a promising vesicular size of 281.62 ± 1.73 nm, a zeta potential of - 22.73 ± 0.06 mV, and a high entrapment efficiency of 96.55% ± 0.25%, which favors lymphatic targeting. In vivo pharmacokinetic studies of EML-AG showed significant enhancement (> sixfold increase) in the rate and extent of AG absorption compared with free AG. However, intraperitoneal injection of a cycloheximide inhibitor caused a significant decrease in AG absorption (~ 52%), confirming the lymphatic targeting potential of EMLs. Therefore, EMLs can be a promising novel nanoplatform for circumventing AG oral delivery obstacles and provide targeted delivery to the lymphatic system at a lower dose with fewer side effects.

Acute Oral Toxicity Evaluation of Andrographolide Self-Nanoemulsifying Drug Delivery System (SNEDDS) Formulation

Context:

Andrographolide (AND) is an active compound of well-known medicinal plant Andrographis paniculata. It has been widely published for various activities. AND is difficult to develop into dosage form due to its poor solubility and bioavailability. This problem could be solved by using self-nanoemulsifying drug delivery system (SNEDDS) for its formulation. However, the increase of bioavailability might result in potential toxicity as a large amount of drug is absorbed.

Aims:

The aim of this study is to evaluate the acute potential toxicity using Organization for Economic Cooperation and Development (OECD) test: 401 methods.

Subjects and Methods:

The OECD 401 method employs groups of animals treated by a single dose or repeated dose (<24 h) of the drug with three variances of doses. In this study, thirty male Wistar rats were divided into five groups which consisted two groups of control and three groups of AND SNEDDS formulation (500, 700, and 900 mg/kg body weight [BW], respectively). Intensive observation of toxicity symptom was performed during the first 30 minutes followed by periodic observation for 14 days. Posttermination, histopathological examination of the liver and kidney was conducted to confirm the toxicity symptoms. To determine the level of toxicity, the lethal dose 50 (LD₅₀) value was calculated at the end of the study.

Results:

The result showed that all groups presented similar toxicological symptoms such as salivation, lethargy, and cornea reflex. However, based on histopathological examination, there were abnormalities, but still in an early stage. The toxicological symptom that emerged seems related to the SNEDDS formulation with lipophilic properties. Furthermore, the value of LD₅₀ was 832.6 mg/kg BW (po).

Conclusions:

The AND SNEDDS formulation was slightly toxic in male Wistar rats po.

Anticancer potential of andrographolide from Andrographis paniculata (Burm.f.) Nees and its mechanisms of action

ETHNOPHARMACOLOGICAL RELEVANCE

Synthetic drugs used for cancer treatment have side effects that may be immunosupressive, can cause liver, kidney and cardiac toxicity, and infertility and ovarian failure, among others. Thus, herbal drugs could be used in the cancer treatment as an adjuvant therapy. Andrographis paniculata (Burm.f.) Nees (AP) is one of the traditional herbs used in different alternative medicinal systems such as Ayurveda, Unani, Chinese, Malayi, Siddha, etc. for the treatment of various disorders and diseases including cancer.

AIM OF THE STUDY

The aim of writing this review is to highlight the medicinal importance of AP and its main phytoconstituent andrographolide (AG). The main emphasis was given on the anticancer activity of AG, its proposed mechanisms of action, novel approaches used to improve its biopharmaceutical properties with the perspective of evidence-based research, and its development as an adjuvant therapy for cancer treatment in future.

MATERIALS AND METHODS

Literature survey was conducted and research papers were retrieved from different databases such as Pubmed, Google Scholar, ACS, Wiley online library, ScienceDirect, Springer, and Scopus during 1970-2020. Research articles, review articles, and short communications, etc. were used for this purpose. The papers were selected on the basis of exclusion and inclusion criteria.

RESULTS

Different anticancer mechanisms of AG have been reportedly proven such as cell cycle arrest, apoptosis, NF-κβ inhibition, antiangiogenesis, cytokine inhibition, etc. whereas its pharmacokinetic properties showed its highly protein bound nature, Cyt P400 (CYP) inhibition, low aqueous solubility, poor oral bioavailability, etc. Different novel formulations of AG have been investigated to increase its bioavailability for better efficacy.

CONCLUSION

This review can provide knowledge about the potential applicability of AP or AG as an adjuvant therapy in cancer treatment. Further research is needed before making any conclusion about the efficacy in humans as an adjuvant therapy in cancer.

Simvastatin nanosuspensions prepared using a combination of pH-sensitive and timed-release approaches for potential treatment of colorectal cancer

A dual pH- and time-dependent polymeric coated capsule was developed to achieve the site specificity of simvastatin (SIM) release in the colon. To improve the SIM solubility, soluplus-based nanosuspension of the drug were prepared by applying the anti-solvent crystallization technique; this was then followed by lyophilization. Particle size, polydispersity index, and saturation solubility were evaluated. The optimized nanosuspension was combined with SLS and freeze-dried before filling into hard gelatin capsules. Drug release characteristics of the coated capsules were studied in HCl 0.1 N, the phosphate buffers 6.8 and 7.4, and the simulated colonic fluid (pH 6.8). The in-vitro cytotoxic effects of SIM nanoparticles against HT29 cells were then evaluated using the MTT assay. The prepared nanoparticles were spherical with a mean size of 261.66 nm, the zeta potential of -18.20 and the dissolution efficiency of 59.71%. X-ray diffraction and differential scanning calorimetry studies showed that the nanosizing technique transformed the crystalline drug into the more soluble amorphous form. The coated capsules had no release in the gastric media, providing the specific delivery of SIM in the colon. The cytotoxic effect of the SIM nanoparticles was significantly increased, as compared to the free SIM. The findings, therefore, showed that the coated capsules using the two polymers of ethyl cellulose and Eudragit S100 could be suitable for the colon target delivery of SIM.

Current Trends on Repurposing and Pharmacological Enhancement of Andrographolide

Andrographolide, the main bioactive component separated from Andrographis paniculata in 1951, has been scrutinized with a modern drug discovery approach for anti-inflammatory properties since 1984. Identification of new uses of existing drugs can be facilitated by searching for evidence linking them to known or yet undiscovered drug targets and human disease states to develop new therapeutic indications.Furthermore, a wide spectrum of biological properties of andrographolide such as anticancer, antibacterial, antiviral, hepatoprotective, antioxidant, anti-malarial, anti-atherosclerosis are also reported. However, poor water solubility and instability limit its clinical application. It becomes crucial to enhance its pharmacological function and find a new treatment option for more diseases. Therefore, this article reviews the major recent developments in andrographolide, including repurposing applications in different diseases and underlying mechanisms, particularly focusing on pharmacological enhancement of andrographolide such as derivatives, chemical modifications with potent biological activity and drug delivery. The repurposing and pharmacological enhancement of andrographolide would not only have exciting therapeutic potential to different diseases to facilitate drug marketing, but also decrease the economic burden on healthcare worldwide.

Investigation of Formulation and Process Parameters of Wet Media Milling to Develop Etodolac Nanosuspensions

PURPOSE

Etodolac (ETD) is one of the non-steroidal anti-inflammatory drugs which has low aqueous solubility issues. The objective of this study was to develop ETD nanosuspensions to improve its poor aqueous solubility properties while investigating formulation and process parameters of wet media milling method via design of experiment (DoE) approach.

METHODS

The critical formulation parameters (CFP) were selected as ETD amount, stabilizer type and ratio as well as critical process parameters (CPP) which were bead size, milling time and milling speed. The two-factorial-2³ and The Box-Benkhen Designs were generated to evaluate CFP and CPP, respectively. Particle size (PS), polydispersity index (PDI) and zeta potential (ZP) were analyzed as dependent variables. Characterization, physical stability and solubility studies were performed.

RESULTS

Optimum nanosuspensions stabilized by PVP K30 and Poloxamer 188 showed 188.5 ± 1.6 and 279.3 ± 6.1 nm of PS, 0.161 ± 0.049 and 0.345 ± 0.007 PDI, 14.8 ± 0.3 and 16.5 ± 0.4 mV of ZP values, respectively. The thermal properties of ETD did not change after milling and lyophilization process regarding to DSC analysis. Also, the crystalline state of ETD was preserved. The morphology of particle was smooth and spherical on SEM. The dry-nanosuspensions stayed physically stable for six months at room temperature. The solubility of nanosuspensions increased up to 13.0-fold in comparison with micronized ETD.

CONCLUSIONS

In conclusion, it is found that the poor solubility issue of ETD can be solved by nanosuspension. DoE approach provided benefits such as reducing number of experiments, saving time and improving final product quality by using wet media milling.

Fabrication of Ibrutinib Nanosuspension by Quality by Design Approach: Intended for Enhanced Oral Bioavailability and Diminished Fast Fed Variability

Present study was aimed to increase the oral bioavailability and reduce the fast fed variability of Ibrutinib by developing nanosuspension by simple precipitation-ultrasonication method. A three factor, three level, box-behnken design was used for formulation optimization using pluronic F-127 as stabilizer. Size and polydispersity index of the developed formulations were in the range of 278.6 to 453.2 nm and 0.055 to 0.198, respectively. Field emission scanning electron microscope (FESEM) revealed discrete units of nanoparticles. Further, differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) studies confirmed the transformation of crystal drug to amorphous. The amorphous nature was retained after 6-month storage at room temperature. Size reduction to nano range and polymorphic transformation (crystalline to amorphous) increased the solubility of nanosuspension (21.44-fold higher as compared to plain drug). In vivo studies of plain drug suspension displayed a significant pharmacokinetic variation between fasting and fed conditions. The formulation had shown increased C_max (3.21- and 3.53-fold), AUC_0-t (5.21- and 5.83-fold) in fasting and fed states compared to that of values obtained for plain drug in fasting state (C_max 48.59 ± 3.30 ng/mL and AUC_0-t 137.20 ± 35.47 ng.h/mL). Significant difference was not observed in the pharmacokinetics of nanosuspension in fasting and fed states. The formulation had improved solubility in the intestinal pH, which might be the driving force behind the decreased precipitation and increased absorption at intestinal region. Optimistic results demonstrated nanosuspension as a promising approach for increasing the solubility, extent of absorption and diminishing the fast fed variability.

FSE-Ag complex NS: preparation and evaluation of antibacterial activity

Silver (Ag) complexes of drugs and their nanosystems have great potential as antibacterials. Recently, an Ag complex of furosemide (Ag-FSE) has shown to be a promising antimicrobial. However, poor solubility of Ag-FSE could hamper its introduction into clinics. Therefore, the authors developed a nanosuspension of Ag-FSE (Ag-FSE_NS) for its solubility and antibacterial activity enhancement. The aim of this study was to introduce a novel nanoantibiotic with enhanced antibacterial efficacy. Ag-FSE_NS was prepared by precipitation-ultrasonication technique. Size, polydispersity index (PI) and zeta potential (ZP) of prepared Ag-FSE_NS were measured by dynamic light scattering, whereas surface morphology was determined using scanning electron microscopy (SEM). In vitro antibacterial activity was evaluated against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa using broth microdilution method. Size, PI and ZP of optimised Ag-FSE_NS1 were 191.2 ± 19.34 nm, 0.465 ± 0.059 and -55.7 ± 8.18 mV, respectively. SEM revealed that Ag-FSE_NS1 particles were rod or needle-like with smooth surfaces. Saturation solubility of Ag-FSE in NS increased eight-fold than pure Ag-FSE. Ag-FSE_NS1 exhibited two-fold and eight-fold enhancements in activity against E. coli and S. aureus, respectively. The results obtained showed that developed Ag-FSE_NS1 holds a promise as a topical antibacterial.

Intranasal Zotepine Nanosuspension: intended for improved brain distribution in rats

BACKGROUND

Zotepine (ZTP), an antipsychotic drug is well tolerated and particularly effective for treating negative symptoms of psychosis. But is limited by low oral bioavailability caused by substantial first pass metabolism and thereby less amount of drug reaches the brain due to blood brain barrier (BBB).

OBJECTIVES

Since ZTP displays dose dependent side effects, purpose of the contemporary study is to develop zotepine loaded nanosuspension (ZTP-NS) for increased brain targeting in rats at lower doses.

METHODS

ZTP-NS is prepared by two techniques viz., sonoprecipitation (SP) and combination technique (high pressure homogenization preceded by precipitation) by employing various stabilizers. Optimized ZTP-NS was characterized for particle size, solid state, morphology and solubility. In vitro drug release of ZTP and formulations was conducted using Franz diffusion cell. Stability study was performed at different temperature conditions. Pharmacokinetic study was performed in Wistar rats to determine the bioavailability and brain distribution of ZTP after intra-nasal (IN) and intravenous (IV) administration. Histopathology of brain was done after repeated administration of IN ZTP dispersion and NS up to 14 days.

RESULTS

The optimized ZTP-NS formulated with Pluronic F-127 (0.3%w/v), Hydroxypropyl methyl cellulose E15 (0.3%w/v) and soya lecithin (0.4%w/v) showed particle size of 519.26 ± 10.44 nm & 330.2 ± 12.90 nm and zeta potential of -21.7 ± 1.39 mV and - 18.26 ± 1.64 mV with sonoprecipitation and combination technique respectively. In vitro drug release was high (81.79 ± 3.23%) for ZTP-NS prepared by combination technique. Intranasal NS resulted in high brain concentrations of 8.6 fold (sonoprecipitation) and 10.79-fold hike in AUC_0-24h in contrast to intravenous ZTP solution. Histopathology results reveal no significant changes in brain microscopic images.

CONCLUSION

ZTP-NS was successfully developed, characterized and found that nanosuspension is a favorable approach for intranasal delivery of zotepine. Graphical abstract Graphical abstract representing zotepine drawbacks, nanosuspension preparation, characterization and pharmacokinetic study in rats.

Development of daidzein nanosuspensions: Preparation, characterization, in vitro evaluation, and pharmacokinetic analysis

The purpose of this investigation was to improve the solubility and oral bioavailability of daidzein via preparing nanosuspensions (NS) with steric stabilizers, electrostatic stabilizers, or a combination of both. Based on particle size and zeta potential, daidzein NS stabilized by HP-β-CD, soy lecithin, HP-β-CD + soy lecithin, TPGS, TPGS + SBE-β-CD, SDS, or HPMC E5 + SDS were generated and characterized by scanning electron microscopy, powder X-ray diffraction, and Fourier transform-infrared spectroscopy. In addition, the stability, cytotoxicity, solubility, dissolution, and pharmacokinetics of NS were evaluated. The resulting daidzein NS were physically stable and biocompatible and presented as regular shapes with homogenous particle sizes of 360-600 nm and decreased crystallinity. Due to the increased solubility and dissolution rate, the oral bioavailability of daidzein NS in rats was 1.63-2.19 times greater than that of crude daidzein. In particular, among the investigated seven daidzein NS formulations, daidzein NS prepared with the costabilizers HPMC E5 + SDS is an optimal formulation for increased daidzein bioavailability. The present study proposes that the combined usage of steric and electrostatic stabilizers is a promising strategy for improving the bioavailability of water-insoluble flavonoid compounds by an NS approach.

A polymeric micelle with an endosomal pH-sensitivity for intracellular delivery and enhanced antitumor efficacy of hydroxycamptothecin

Amphiphilic poly(ethylene glycol)-imino-poly(benzyl-l-aspartate) (PIPA) and poly(ethylene glycol)-poly(benzyl-l-aspartate) (PPA) block copolymers were synthesized as pH-responsive and pH-nonresponsive copolymers, respectively. Polymer micelles were fabricated by the film dispersion method, and hydroxycamptothecin (HCPT) was physically encapsulated into the micelles. The average diameter of the HCPT-loaded PIPA micelles (PIPAH micelles) was approximately 230 nm, which was slightly smaller than that of the HCPT-loaded PPA micelles (PPAH micelles, approximately 260 nm). The drug-loading content and encapsulation efficiency of the PIPAH micelles (3.33% and 68.89%, respectively) were slightly higher than those of the PPAH micelles (2.90% and 59.68%, respectively). The PIPAH micelles exhibited better colloid stability, storage stability, and plasma stability than the PPAH micelles. Drug release from the PIPAH micelles with imino groups was pH dependent, and more than 75% or 65% of the loaded HCPT was released within 24 h in weakly acidic media (pH 5.0 or 6.0, respectively). An in vitro cell assay demonstrated that the pH-sensitive micelles exhibited potent suppression of cancer cell proliferation and little cytotoxicity on normal cells. Additionally, these micelles could be efficiently internalized by the tumor cells through macropinocytosis- and caveolin-mediated endocytotic pathways. HCPT-loaded micelles had longer circulation time than the HCPT solution in a pharmacokinetic study. In vivo antitumor experiments indicate that the PIPAH micelles had better antitumor efficacy than the pH-insensitive PPAH micelles and the HCPT solution. Therefore, the pH-responsive PIPAH micelles have great potential for high-efficiency delivery of HCPT. STATEMENT OF SIGNIFICANCE: In this study, a new type of pH-responsive amphiphilic copolymer, poly(ethylene glycol)-imino-poly(benzyl-l-aspartate) (PIPA) block copolymer, was synthesized. This copolymer had then self-assembled to form nanomicelles for tumor intracellular delivery of hydroxycamptothecin (HCPT) for the first time. In in vitro test, the PIPAH micelles exhibited adequate stability and pH-dependent drug release. To one's excitement, the PIPAH micelles exhibited better antitumor efficacy and biosafety than the pH-insensitive micelles (PPAH) and the HCPT solution in in vitro and in vivo antitumor experiments. Therefore, the pH-responsive micelles in this study have significant potential to be used for high-performance delivery of HCPT and potentially for the targeted delivery of other cancer therapeutic agents. The polymer designed in this study can be used as a carrier of poorly soluble drugs or other active ingredients.

Study on Formulation, in vivo Exposure, and Passive Targeting of Intravenous Itraconazole Nanosuspensions

The pharmacokinetic profile of a drug can be different when delivered as a nanosuspension compared with a true solution, which may in turn affect the therapeutic effect of the drug. The goal of this study was to prepare itraconazole nanosuspensions (ITZ-Nanos) stabilized by an amphipathic polymer, polyethylene glycol-poly (benzyl aspartic acid ester) (PEG-PBLA), by the precipitation-homogenization, and study the pharmacokinetic profile of the ITZ-Nanos. The particle size and morphology of nanosuspensions were determined by Zetasizer and field emission scanning electron microscope (SEM), respectively. The dissolution profile was evaluated using a paddle method according to Chinese Pharmacopoeia 2015. The level of ITZ in plasma and tissues was measured by a HPLC method. The optimized ITZ-Nanos had an average particle size of 268.1 ± 6.5 nm and the particles were in a rectangular form. The dissolution profile of ITZ-Nanos was similar to that of commercial ITZ injections, with nearly 90% ITZ released in the first 5 min. The ITZ-Nanos displayed different pharmacokinetic properties compared with the commercial ITZ injections, including a decreased initial drug concentration, increased plasma half-life and mean residence time (MRT), and increased concentration in the liver, lung, and spleen. The ITZ-Nanos can change the in vivo distribution of ITZ and result in passive targeting to the organs with mononuclear phagocyte systems (MPS).

Overview of pharmacological activities of Andrographis paniculata and its major compound andrographolide

Andrographis paniculata (A. paniculata) is a medicinal plant traditionally used as anti-inflammation and anti-bacteria herb. Andrographolide, the major active component of A. paniculata, exhibits diverse pharmacological activities, including anti-inflammation, anti-cancer, anti-obesity, anti-diabetes, and other activities. In this article, we comprehensively review the therapeutic potential of A. paniculata and andrographolide focusing on the mechanisms of action and clinical application. We systemically discuss the structure-activity relationship of andrographolide and derivatives. Despite the various pharmacological activities and formula of A. paniculata and andrographolide, we propose further development of more structural derivatives of andrographolide with reduced toxicity and increased therapeutic efficacy is still needed for the clinical application of this ancient mighty herb and its major component.

A novel albumin wrapped nanosuspension of meloxicam to improve inflammation-targeting effects

Background

The objective of this study was to develop a more bio-available and safe nanosuspension of meloxicam (MX), which could dramatically improve inflammation targeting.

Methods and results

MX-loaded bovine serum albumin (BSA) nanosuspensions were prepared using acid–base neutralization in aqueous solution and the prepared nanosuspensions were characterized. The results obtained showed that the prepared nanosuspensions had a narrow size distribution with a mean particle size of 78.67±0.22 nm, a polydispersity index of 0.133±0.01, and a zeta potential of −11.87±0.91 mV. The prepared MX nanosuspensions were spherically wrapped by BSA with a smooth surface as shown by transmission electron microscopy. Stability studies showed that the nanosuspensions were physically stable at 4°C with a shelf life of at least 6 months. In the in vitro dissolution test, the MX-loaded BSA nanosuspension (MX-BSA-NS) exhibited sustained release. In addition, an in vivo pharmacokinetic study in rats following intravenous injection showed that the half-life (t_1/2), mean residence time (MRT), and area under the concentration–time curve (AUC_0–∞) of MX-BSA-NS was increased by 169.83%, 150.13%, and 148.80%, respectively, in comparison with MX conventional solution (MX solution). Furthermore, results from inflammation targeting studies showed that the concentration of MX increased significantly in inflamed tissues but was reduced in normal tissues compared with the MX solution group after injection of MX-BSA-NS.

Conclusion

The prepared MX-BSA-NS significantly increased the inflammation-targeting properties and bioavailability of MX, suggesting its potential as a promising formulation for the targeted drug delivery of MX in future clinical applications.

Comparative studies on amphotericin B nanosuspensions prepared by a high pressure homogenization method and an antisolvent precipitation method

Amphotericin B (AmB) is a widely used polyene antifungal agent; however, its poor solubility limits its clinical application. In this study, AmB nanosuspensions were prepared by a high pressure homogenization method (AmB-HPH) and an antisolvent precipitation method (AmB-AP) to improve the drug solubility. To reveal the distinct influences of these two different preparation methods, systematic comparisons of particle size, crystalline state, wettability, in vitro dissolution and in vivo pharmacokinetics on the properties of AmB-HPH and AmB-AP were performed. The results indicated that AmB-AP was in an amorphous state, exhibiting higher saturation solubility and dissolution rate than those of AmB-HPH in the crystalline state. However, the relative bioavailability of AmB-HPH was higher than that of AmB-AP in vivo, which was likely attributed to its better stability. In conclusion, both AmB-HPH and AmB-AP can enhance the solubility and bioavailability of AmB, but the stability of the nanosuspension prepared by the anti-solvent precipitation method should be carefully considered.