Development and evaluation of long-circulating nanoparticles loaded with betulinic acid for improved anti-tumor efficacy

Recent advancements of betulinic acid-based drug delivery systems for cancer therapy (2002-2023)

Betulinic acid, a compound classified as a pentacyclic triterpenoid, is found in abundance in a variety of medicinal plants and natural substances. Its broad spectrum of biological and medicinal properties, particularly its potent antitumor activity, has gained significant attention in recent years. The anticancer properties of betulinic acid are governed by mitochondrial signalling pathways and it exhibit selectivity for cancerous tissue, leaving non-cancerous cells and normal tissue unharmed. This characteristic is particularly valuable in chemo-resistant cases. Nevertheless, the medicinal potential of betulinic acid is hindered by its poor water solubility and short half-life, leading to sub-optimal effectiveness. This issue is being tackled by a variety of nano-sized drug delivery systems, such as polymeric nanoparticles, magnetic nanoparticles, polymeric conjugates, nanoemulsions, liposomes, nanosuspensions, carbon nanotubes, and cyclodextrin complexes. This article focuses on recent advances in nanoformulations that are tailored to the delivery of betulinic acid with enhanced effectiveness.

Polyester nanoparticles delivering chemotherapeutics: Learning from the past and looking to the future to enhance their clinical impact in tumor therapy

Polymeric nanoparticles (NPs), specifically those comprised of biodegradable and biocompatible polyesters, have been heralded as a game-changing drug delivery platform. In fact, poly(α-hydroxy acids) such as polylactide (PLA), poly(lactide-co-glycolide) (PLGA), and poly(ε-caprolactone) (PCL) have been heavily researched in the past three decades as the material basis of polymeric NPs for drug delivery applications. As materials, these polymers have found success in resorbable sutures, biodegradable implants, and even monolithic, biodegradable platforms for sustained release of therapeutics (e.g., proteins and small molecules) and diagnostics. Few fields have gained more attention in drug delivery through polymeric NPs than cancer therapy. However, the clinical translational of polymeric nanomedicines for treating solid tumors has not been congruent with the fervor or funding in this particular field of research. Here, we attempt to provide a comprehensive snapshot of polyester NPs in the context of chemotherapeutic delivery. This includes a preliminary exploration of the polymeric nanomedicine in the cancer research space. We examine the various processes for producing polyester NPs, including methods for surface-functionalization, and related challenges. After a detailed overview of the multiple factors involved with the delivery of NPs to solid tumors, the crosstalk between particle design and interactions with biological systems is discussed. Finally, we report state-of-the-art approaches toward effective delivery of NPs to tumors, aiming at identifying new research areas and re-evaluating the reasons why some research avenues have underdelivered. We hope our effort will contribute to a better understanding of the gap to fill and delineate the future research work needed to bring polyester-based NPs closer to clinical application. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Effect of mPEG-PLGA on Drug Crystallinity and Release of Long-Acting Injection Microspheres: In Vitro and In Vivo Perspectives

PURPOSE

Traditional progesterone (PRG) injections require long-term administration, leading to poor patient compliance. The emergence of long-acting injectable microspheres extends the release period to several days or even months. However, these microspheres often face challenges such as burst release and incomplete drug release. This study aims to regulate drug release by altering the crystallinity of the drug during the release process from the microspheres.

METHODS

This research incorporates methoxy poly(ethylene glycol)-b-poly(lactide-co-glycolide) (mPEG-PLGA) into poly(lactide-co-glycolide) (PLGA) microspheres to enhance their hydrophilicity, thus regulating the release rate and drug morphology during release. This modification aims to address the issues of burst and incomplete release in traditional PLGA microspheres. PRG was used as the model drug. PRG/mPEG-PLGA/PLGA microspheres (PmPPMs) were prepared via an emulsification-solvent evaporation method. Scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), and differential scanning calorimetry (DSC) were employed to investigate the presence of PRG in PmPPMs and its physical state changes during release.

RESULTS

The addition of mPEG-PLGA altered the crystallinity of the drug within the microspheres at different release stages. The crystallinity correlated positively with the amount of mPEG-PLGA incorporated; the greater the amount, the faster the drug release from the formulation. The bioavailability and muscular irritation of the long-acting injectable were assessed through pharmacokinetic and muscle irritation studies in Sprague-Dawley (SD) rats. The results indicated that PmPPMs containing mPEG-PLGA achieved low burst release and sustained release over 7 days, with minimal irritation and self-healing within this period. PmPPMs with 5% mPEG-PLGA showed a relative bioavailability (Frel) of 146.88%.

IN CONCLUSION

In summary, adding an appropriate amount of mPEG to PLGA microspheres can alter the drug release process and enhance bioavailability.

d-α-tocopheryl polyethylene glycol 1000 succinate surface scaffold polysarcosine based polymeric nanoparticles of enzalutamide for the treatment of colorectal cancer: In vitro, in vivo characterizations

In this study, Enzalutamide (ENZ) loaded Poly Lactic-co-Glycolic Acid (PLGA) nanoparticles coated with polysarcosine and d-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) were prepared using a three-step modified nanoprecipitation method combined with self-assembly. A three-factor, three-level Box-Behnken design was implemented with Design-Expert® software to evaluate the impact of three independent variables on particle size, zeta potential, and percent entrapment efficiency through a numeric optimization approach. The results were corroborated with ANOVA analysis, regression equations, and response surface plots. Field emission scanning electron microscopy and transmission electron microscope images revealed nanosized, spherical polymeric nanoparticles (NPs) with a size distribution ranging from 178.9 ± 2.3 to 212.8 ± 0.7 nm, a zeta potential of 12.6 ± 0.8 mV, and entrapment efficiency of 71.2 ± 0.7 %. The latter increased with higher polymer concentration. Increased polymer concentration and homogenization speed also enhanced drug entrapment efficiency. In vitro drug release was 85 ± 22.5 %, following the Higuchi model (R2 = 0.98) and Fickian diffusion (n < 0.5). In vitro cytotoxicity assessments, including Mitochondrial Membrane Potential Estimation, Apoptosis analysis, cell cycle analysis, Reactive oxygen species estimation, Wound healing assay, DNA fragmentation assay, and IC50 evaluation with Sulforhodamine B assay, indicated low toxicity and high efficacy of polymeric nanoparticles compared to the drug alone. In vivo studies demonstrated biocompatibility and target specificity. The findings suggest that TPGS surface-scaffolded polysarcosine-based polymer nanoparticles of ENZ could be a promising and safe delivery system with sustained release for colorectal cancer treatment, yielding improved therapeutic outcomes.

Development of curcumin-loaded galactosylated chitosan-coated nanoparticles for targeted delivery of hepatocellular carcinoma

Curcumin (CUR) has good antitumor effects, but its poor aqueous solubility severely limits its clinical application and the systemic nonspecific distribution of the free drug in tumor patients is a key therapeutic challenge. In order to overcome the limitations of free drugs and improve the therapeutic efficacy, we developed novel galactosylated chitosan (GC)-modified nanoparticles (GC@NPs) based on poly (ethylene glycol) methyl ether-block-poly (lactide-co-glycolide) (PEG-PLGA), which can target asialoglycoprotein receptor (ASGPR) expressed on hepatocellular carcinoma cells and have excellent biocompatibility. The results showed that the drug loading (DL) of CUR was approximately 4.56 %. A favorable biosafety profile was maintained up to concentrations of 500 μg/mL. Furthermore, in vitro cellular assays showed that GC@NPs could be efficiently internalized by HepG2 cells via ASGPR-mediated endocytosis and successfully released CUR for chemotherapy. More importantly, in vivo anti-tumor experiments revealed that GC@NPs were able to accumulate effectively within tumor sites through EPR effect and ASGPR-mediated endocytosis, leading to superior inhibition of tumor growth compared to free CUR. Overall, GC@NPs are a promising CUR nanocarrier for enhanced tumor therapy with a good biosafety profile.

Long-Circulating Lipid Nanospheres Loaded with Flurbiprofen Axetil for Targeted Rheumatoid Arthritis Treatment

Background

Flurbiprofen axetil (FA) is a non-steroidal anti-inflammatory drug with good analgesic and anti-inflammatory effects. However, it suffers from poor solubility, short circulation time, and off-target binding profile, which significantly limit its clinical application. Here, we loaded FA into stealth lipid microspheres modified with the arginine-glycine-aspartic acid (RGD) peptide (cRGD-FA-SLM), and examined the therapeutic potential of the resulting platform for the treatment of rheumatoid arthritis (RA).

Methods

cRGD-FA-SLM was prepared by high pressure homogenization, and its toxicity and uptake by macrophages were examined using cultures of RAW264.7 cells. Hemolysis and hepatotoxicity tests were performed to assess the safety of the developed platform, while its pharmacokinetics, biodistribution, and therapeutic efficacy were investigated in a collagen-induced arthritis rat model.

Results

cRGD-FA-SLM showed homogeneous spherical morphology and efficient encapsulation of FA. The developed platform was non-toxic to normal macrophages and was selectively internalized by lipopolysaccharide-activated macrophages in vitro, while it distributed mainly to arthritic joints and significantly prolonged FA in circulation in vivo. cRGD-FA-SLM also significantly reduced the expression of prostaglandin E2 and alleviated joint edema and bone erosion, showing prolonged analgesic effects in arthritic rats.

Conclusion

cRGD-FA-SLM shows good inflammation-targeting ability and prolongs drug circulation in vivo, suggesting promise as an anti-inflammatory and analgesic agent for targeted RA treatment.

Impact of the Drug Loading Method on the Drug Distribution and Biological Efficacy of Exosomes

Exosomes are biological nanovesicles that are intrinsically loaded with thousands of biomacromolecules and are principally responsible for cell-to-cell communication. Inspired by the natural payload, they have been extensively investigated as drug delivery vehicles; however, the drug distribution, whether into or onto exosomes, is still debatable. In the present work, we have tried to investigate it systemically by selecting 5-fluorouracil (5-FU) (hydrophilic) and paclitaxel (PAC) (hydrophobic), drugs with very different physicochemical characteristics, for the loading to the exosomes. Exosomes were obtained from bovine milk, and the drugs were loaded using three different methods: incubation, sonication, and triton x-100. The particle size was found to be approximately 100 nm in all the cases; however, the highest drug loading was found in the sonication method. Fluorescence spectrophotometer, EDX analysis, EDX mapping, XPS, and XRD analysis indicated the possible presence of more drugs over the surface in the case of the incubation method. Drugs loaded by the sonication method had more controlled release than simple incubation and triton x-100. The method of drug loading had an insignificant effect on the cytotoxicity while in line with our previous observation, the combination (PAC and 5-FU) exhibited synergism as evidenced by ROS assay, colony formation assay, and mitochondrial membrane potential assay.

Polyethyleneglycol-Betulinic Acid (PEG-BA) Polymer-Drug Conjugate Induces Apoptosis and Antioxidation in a Biological Model of Pancreatic Cancer

Pancreatic cancer (PC) is one of the most aggressive solid malignancies with poor treatment response and low survival rates. Herbal medicines such as betulinic acid (BA) have shown potential in treating various solid tumours, but with limitations that can be circumvented by polymer-drug conjugation. Polyethylene glycol-BA (PEG-BA) polymer-drug conjugate has previously shown selective anticancer activity against PC cells. Here, we elucidate the mechanism of cell death and the cell death pathway, anti-inflammatory and antioxidant activities of PEG-BA. PEG-BA induced apoptotic cell death by arresting MIA-PaCa-2 cells in the Sub-G1 phase of the cell cycle compared with BA and untreated cells (39.50 ± 5.32% > 19.63 ± 4.49% > 4.57 ± 0.82%). NFκB/p65 protein expression was moderately increased by PEG-BA (2.70 vs. 3.09 ± 0.42 ng/mL; p = 0.1521). However, significant (p < 0.05) overexpression of the proapoptotic genes TNF (23.72 ± 1.03) and CASPASE 3 (12,059.98 ± 1.74) compared with untreated cells was notable. The antioxidant potential of PEG-BA was greater (IC50 = 15.59 ± 0.64 µM) compared with ascorbic acid (25.58 ± 0.44 µM) and BA-only (>100 µM) and further confirmed with the improved reduction of hydroperoxide levels compared with BA-only (518.80 ± 25.53 µM vs. 542.43 ± 9.70 µM). In conclusion, PEG-BA activated both the intrinsic and extrinsic pathways of apoptosis and improved antioxidant activities in PC cells, suggesting enhanced anticancer activity upon conjugation.

Tracing the Anti-cancer Mechanism of Pleurotus osteratus by the Integrative Approach of Network Pharmacology and Experimental Studies

The present study identified the probable mechanism behind the anti-cancer activity of the hexane fraction of Pleurotus osteratus (HFPO) using network pharmacology and experimental validation. HFPO myco-metabolites targets and targets related to the cancer were mined from the online web server, and overlapping targets were screened. Out of the 74 overlapping targets, 33 targets were identified in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway of cancer. Furthermore, the main active myco-metabolites and hub targets were identified by network analysis of the compound-targets network and protein-protein interaction (PPI), respectively. Molecular docking results showed good binding affinity of the hub targets with their respective myco-metabolites. HFPO induced in-vitro anti-cancer activity by affecting the PI3K-AKT-mTOR pathway, besides time-dependent cell cytotoxicity and apoptotic cell body formation. Additionally, tumor volume reduction was observed in HFPO-treated Ehrlich ascites carcinoma (EAC) bearing Swiss albino mice. Overall, HFPO induces anti-cancer potential by modulating the PI3K-AKT-mTOR signaling pathway.

Biodegradable PEG-PCL Nanoparticles for Co-delivery of MUC1 Inhibitor and Doxorubicin for the Confinement of Triple-Negative Breast Cancer

Combating triple-negative breast cancer (TNBC) is still a problem, despite the development of numerous drug delivery approaches. Mucin1 (MUC1), a glycoprotein linked to chemo-resistance and progressive malignancy, is unregulated in TNBC. GO-201, a MUC1 peptide inhibitor that impairs MUC1 activity, promotes necrotic cell death by binding to the MUC1-C unit. The current study deals with the synthesis and development of a novel nano-formulation (DM-PEG-PCL NPs) comprising of polyethylene glycol-polycaprolactone (PEG-PCL) polymer loaded with MUC1 inhibitor and an effective anticancer drug, doxorubicin (DOX). The DOX and MUC1 loaded nanoparticles were fully characterized, and their different physicochemical properties, viz. size, shape, surface charge, entrapment efficiencies, release behavior, etc., were determined. With IC₅₀ values of 5.8 and 2.4 nm on breast cancer cell lines, accordingly, and a combination index (CI) of < 1.0, DM-PEG-PCL NPs displayed enhanced toxicity towards breast cancer cells (MCF-7 and MDA-MB-231) than DOX-PEG-PCL and MUC1i-PEG-PCL nanoparticles. Fluorescence microscopy analysis revealed DOX localization in the nucleus and MUC1 inhibitor in the mitochondria. Further, DM-PEG-PCL NPs treated breast cancer cells showed increased mitochondrial damage with enhancement in caspase-3 expression and reduction in Bcl-2 expression.In vivo evaluation using Ehrlich Ascites Carcinoma bearing mice explicitly stated that DM-PEG-PCL NPs therapy minimized tumor growth relative to control treatment. Further, acute toxicity studies did not reveal any adverse effects on organs and their functions, as no mortalities were observed. The current research reports for the first time the synergistic approach of combination entrapment of a clinical chemotherapeutic (DOX) and an anticancer peptide (MUC1 inhibitor) encased in a diblock PEG-PCL copolymer. Incorporating both DOX and MUC1 inhibitors in PEG-PCL NPs in the designed nanoformulation has provided chances and insights for treating triple-negative breast tumors. Our controlled delivery technology is biodegradable, non-toxic, and anti-multidrug-resistant. In addition, this tailored smart nanoformulation has been particularly effective in the therapy of triple-negative breast cancer.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10924-022-02654-4.

Novel Curcumin Derivative-Decorated Ultralong-Circulating Paclitaxel Nanoparticles: A Novel Delivery System with Superior Anticancer Efficacy and Safety

Purpose

Paclitaxel (PTX) has been widely utilized for the treatment of breast cancer. However, drawbacks, such as poor aqueous solubility, rapid blood clearance and severe toxicity, greatly reduce its efficacy and safety. Herein, a novel self-developed curcumin derivative (CUD) was chosen as the carrier to develop a long-acting PTX nano-delivery system (PTX-Sln@CUD) in order to improve its pharmacokinetic behavior, anti-breast cancer efficacy and safety.

Methods

PTX-Sln@CUD was prepared using solid dispersion and ultrasonic technology. Relevant physical and chemical properties, including stability and release behavior, were characterized. The clearance of PTX-Sln@CUD in vivo was studied by pharmacokinetic experiments. The anti-tumor activity of PTX-Sln@CUD was investigated in vitro and in vivo. Hemolysis experiments, acute toxicity and cumulative toxicity studies were performed in mice to determine the safety of PTX-Sln@CUD.

Results

The average particle size, PDI, Zeta potential, encapsulation efficiency and loading efficiency of the PTX-Sln@CUD were 238.5 ± 4.79 nm, 0.225 ± 0.011, −33.8 ± 1.26 mV, 94.20 ± 0.49% and 10.98 ± 0.31%, respectively. PTX-Sln@CUD was found to be stable at room temperature for half a year. The cumulative release rates of PTX-Sln@CUD at 24, 96 and 168 h were 17.98 ± 2.60, 57.09 ± 2.32 and 72.66 ± 4.16%, respectively, which were adherent to zero-order kinetics. T_1/2, MRT _(0-t) and AUC _(0-t) of the PTX-Sln@CUD group were 4.03-fold (44.293 h), 7.78-fold (38.444 h) and 6.18-fold (14.716 mg/L*h) of the PTX group, respectively. PTX-Sln@CUD group demonstrated stronger anti-breast cancer activity than the PTX group. Importantly, the PTX-Sln@CUD group was safer compared to the PTX group both in vitro and in vivo.

Conclusion

PTX-Sln@CUD was verified as promising therapeutic nanoparticles for breast cancer and provided a novel strategy to solve the problem of low efficacy and poor safety of clinical chemotherapy drugs.

Nanoparticles of naturally occurring PPAR-γ inhibitor betulinic acid ameliorates bone marrow adiposity and pathological bone loss in ovariectomized rats via Wnt/β-catenin pathway

AIMS

Postmenopausal osteoporosis is one of the world's biggest yet unnoticed health issues. After ovariectomy, declined estrogen level significantly contributes to the elevation of bone marrow adiposity and bone loss leading to osteoporosis. Therapeutics to prevent osteoporosis addressing various aspects are now in short supply. In this study we made an approach to synthesize nanoparticles of naturally occurring PPAR-γ inhibitor, betulinic acid (BA/NPs) and tested the same in altered bone metabolisms developed after ovariectomy.

MAIN METHODS

The osteogenic efficacy of BA/NPs was established in human and rat primary osteoblast cells using qRT-PCR and immunoblot analysis. Furthermore, lineage allocations of multipotent bone marrow stromal cells were evaluated. Various aspects of altered bone metabolism after ovariectomy such as bone marrow adiposity and pathological bone loss were evaluated using μCT and histological assessments.

KEY FINDINGS

BA/NPs exert potential osteogenic efficacy by modulating RUNX2 and BMP2. Mechanistically BA/NPs regulate osteoblastogenesis through Wnt/β-catenin signaling. Further, BA/NPs showed the potential to inhibit the differentiation of multipotent BMSCs towards adipogenesis while favouring the osteogenic lineage. In the in vivo study, increased bone marrow adiposity was reduced in ovariectomized rats after BA/NPs treatment as assessed by histology and μCT analysis. Loss of bone mineral density as a hallmark of pathological bone loss was also abrogated by BA/NPs.

SIGNIFICANCE

Our findings imply that BA/NPs could be used further as a viable drug lead to counteract various pathophysiological challenges after menopause.

Preparation of Betulinic Acid Galactosylated Chitosan Nanoparticles and Their Effect on Liver Fibrosis

Aim

Liver fibrosis is mainly characterized by the formation of fibrous scars. Galactosylated chitosan (GC) has gained increasing attention as a liver-targeted drug carrier in recent years. The present study aimed to investigate the availability of betulinic acid-loaded GC nanoparticles (BA-GC-NPs) for liver protection. Covalently-conjugated galactose, recognized by asialoglycoprotein receptors exclusively expressed in hepatocytes, was employed to target the liver.

Materials and Methods

Galactose was coupled to chitosan by chemical covalent binding. BA-GC-NPs were synthesized by wrapping BA into NPs via ion-crosslinking method. The potential advantage of BA-GC-NP as a liver-targeting agent in the treatment of liver fibrosis has been demonstrated in vivo and in vitro.

Results

BA-GC-NPs with diameters <200 nm were manufactured in a virtually spherical core-shell arrangement, and BA was released consistently and continuously for 96 h, as assessed by an in vitro release assay. According to the safety evaluation, BA-GC-NPs demonstrated good biocompatibility at the cellular level and did not generate any inflammatory reaction in mice. Importantly, BA-GC-NPs showed an inherent liver-targeting potential in the uptake behavioral studies in cells and bioimaging tests in vivo. Efficacy tests revealed that administering BA-GC-NPs in a mouse model of liver fibrosis reduced the degree of liver injury in mice.

Conclusion

The findings showed that BA-GC-NPs form a safe and effective anti-hepatic fibrosis medication delivery strategy.

Glycosylated Zein Composite Nanoparticles for Efficient Delivery of Betulinic Acid: Fabrication, Characterization, and In Vitro Release Properties

Betulinic acid (BA) has anti-inflammatory, antioxidative stress, and antitumor activities, but BA bioavailability is low due to its poor water solubility and short half-life. This study aimed to construct a BA delivery system to improve its utilization in vitro. Glycosylated zein (G-zein) was prepared using the wet heating method, and BA-loaded zein composite nanoparticles were prepared using the antisolvent method. Compared to zein, G-zein had the advantages of higher solubility and lower surface hydrophobicity. The encapsulation efficiency of G-zein@BA reached over 80% when the BA concentration was 1 mg/mL. Compared to zein@BA nanoparticles, G-zein@BA was characterized by smaller droplets, higher encapsulation efficiency, and a more stable morphology. The sustained release and solubility of G-zein@BA nanoparticles were also superior to those of zein@BA. Compared with free BA, the dispersions of zein@BA and G-zein@BA nanoparticles in water increased 2.27- and 2.91-fold, respectively. In addition, zein@BA and G-zein@BA nanoparticles markedly inhibited the proliferation of HepG2 cells. This study provides new insights into the structural properties and antitumor activity of BA composite nanoparticles to aid in the development of zein particles as functional materials to deliver bioactive compounds.

Additive Interactions between Betulinic Acid and Two Taxanes in In Vitro Tests against Four Human Malignant Melanoma Cell Lines

The incidence of melanoma is steadily increasing worldwide. Melanoma is the most lethal skin cancer, and new therapeutic methods are being sought. Our research aimed to investigate the cytotoxic and antiproliferative effects of betulinic acid in vitro, used alone and in combination with taxanes (paclitaxel, docetaxel) in four melanoma cell lines. Isobolographic analysis allowed us to assess the interactions between these compounds. Betulinic acid had no cytotoxic effect on normal human keratinocyte HaCaT cells; the amount of LDH released by them was significantly lower compared to melanoma cell lines. The present study shows that betulinic acid significantly inhibits the growth of melanoma cell lines in vitro. The IC50 values of betulinic acid ranged from 2.21 µM to 15.94 µM against the four melanoma lines. Co-treatment of betulinic acid with paclitaxel or docetaxel generated desirable drug–drug interactions, such as an additive and additive with a tendency to synergy interactions.

Development, Characterization, and Investigation of In Vivo Targeted Delivery Efficacy of Luteolin-Loaded, Eudragit S100-Coated mPEG-PLGA Nanoparticles

Luteolin (Lu) is a kind of flavonoid that has been proved to treat non-alcoholic fatty liver disease by alleviating intestinal microbiota disorder. In this study, luteolin was coated with methoxy poly(ethylene glycol)-poly(dl-lactide-co-glycolic acid) (mPEG-PLGA) using an emulsion solvent evaporation method, and the optimum preparation process was determined by a single-factor experiment combined with response surface methodology (RSM). Methacrylic acid-methyl methacrylate (1:2) copolymer (Eudragit S100) was then used to coat the surface of Lu/mPEG-PLGA nanoparticles. The physical parameters of Eudragit S100-coated Lu/mPEG-PLGA nanoparticles (Lu-NPs), such as appearance, particle size, potential, particle size distribution and drug release, and stability in vitro, were evaluated. In addition, its cytotoxicity in vitro, pharmacokinetics, tissue distribution, and toxicity in vivo were also studied. The results showed that the prepared Lu-NPs had uniform particle size distribution, high encapsulation efficiency, and good stability. Normal colonic epithelial cells showed good tolerance to Lu-NPs. After oral administration, the blood concentration of luteolin peaked at 8 h, and the main tissue distribution was within the colon, confirming its colon-targeted profile. Safety assessments also indicated that no significant changes were observed in main organs after administration of Lu-NPs. The use of Eudragit S100-coated Lu/mPEG-PLGA nanoparticles is a new strategy for colon-targeted delivery of luteolin that encourages luteolin to fulfill its role in the colon.

Functionalized Liposome and Albumin-Based Systems as Carriers for Poorly Water-Soluble Anticancer Drugs: An Updated Review

Cancer is one of the leading causes of death worldwide. In the available treatments, chemotherapy is one of the most used, but has several associated problems, namely the high toxicity to normal cells and the resistance acquired by cancer cells to the therapeutic agents. The scientific community has been battling against this disease, developing new strategies and new potential chemotherapeutic agents. However, new drugs often exhibit poor solubility in water, which led researchers to develop functionalized nanosystems to carry and, specifically deliver, the drugs to cancer cells, targeting overexpressed receptors, proteins, and organelles. Thus, this review is focused on the recent developments of functionalized nanosystems used to carry poorly water-soluble drugs, with special emphasis on liposomes and albumin-based nanosystems, two major classes of organic nanocarriers with formulations already approved by the U.S. Food and Drug Administration (FDA) for cancer therapeutics.

Bioactivity of betulinic acid nanoemulsions on skin carcinogenesis in transgenic mice K14E6

Alternative therapies for cancer treatment have been developed using bioactive compounds such as betulinic acid (BA). The objective of this study was to investigate the bioactivity of BA in its free form and compare it with its nano-encapsulated form under a skin carcinogenesis protocol in a genetically modified murine model. K14E6 and FVB mice were divided into four groups to be treated with free BA and with betulinic acid nanoemulsion (BANE). Lecithin enriched with medium chain fatty acids (MCFAs) was employed as an emulsifier to prepare the nanoemulsions with a mean droplet size of 40 nm. Skin tumors were induced by exposure to DMBA and TPA directly to the transgenic mice. Tumor development was completely inhibited by BANE and by 70% with free BA. This was validated by histological sections and the gene expression of the Cdk4 and Casp8 genes.

Natural Biocidal Compounds of Plant Origin as Biodegradable Materials Modifiers

The article presents a literature review of the plant origin natural compounds with biocidal properties. These compounds could be used as modifiers of biodegradable materials. Modification of polymer material is one of the basic steps in its manufacturing process. Biodegradable materials play a key role in the current development of materials engineering. Natural modifiers are non-toxic, environmentally friendly, and renewable. The substances contained in natural modifiers exhibit biocidal properties against bacteria and/or fungi. The article discusses polyphenols, selected phenols, naphthoquinones, triterpenoids, and phytoncides that are natural antibiotics. Due to the increasing demand for biodegradable materials and the protection of the natural environment against the negative effects of toxic substances, it is crucial to replace synthetic modifiers with plant ones. This work mentions industries where materials containing natural modifying additives could find potential applications. Moreover, the probable examples of the final products are presented. Additionally, the article points out the current world's pandemic state and the use of materials with biocidal properties considering the epidemiological conditions.

Natural Products for the Management of Castration-Resistant Prostate Cancer: Special Focus on Nanoparticles Based Studies

Prostate cancer is the most common type of cancer among men and the second most frequent cause of cancer-related mortality around the world. The progression of advanced prostate cancer to castration-resistant prostate cancer (CRPC) plays a major role in disease-associated morbidity and mortality, posing a significant therapeutic challenge. Resistance has been associated with the activation of androgen receptors via several mechanisms, including alternative dehydroepiandrosterone biosynthetic pathways, other androgen receptor activator molecules, oncogenes, and carcinogenic signaling pathways. Tumor microenvironment plays a critical role not only in the cancer progression but also in the drug resistance. Numerous natural products have shown major potential against particular or multiple resistance pathways as shown by in vitro and in vivo studies. However, their efficacy in clinical trials has been undermined by their unfavorable pharmacological properties (hydrophobic molecules, instability, low pharmacokinetic profile, poor water solubility, and high excretion rate). Nanoparticle formulations can provide a way out of the stalemate, employing targeted drug delivery, improved pharmacokinetic drug profile, and transportation of diagnostic and therapeutic agents via otherwise impermeable biological barriers. This review compiles the available evidence regarding the use of natural products for the management of CRPC with a focus on nanoparticle formulations. PubMed and Google Scholar search engines were used for preclinical studies, while ClinicalTrials.gov and PubMed were searched for clinical studies. The results of our study suggest the efficacy of natural compounds such as curcumin, resveratrol, apigenin, quercetin, fisetin, luteolin, kaempferol, genistein, berberine, ursolic acid, eugenol, gingerol, and ellagic acid against several mechanisms leading to castration resistance in preclinical studies, but fail to set the disease under control in clinical studies. Nanoparticle formulations of curcumin and quercetin seem to increase their potential in clinical settings. Using nanoparticles based on betulinic acid, capsaicin, sintokamide A, niphatenones A and B, as well as atraric acid seems promising but needs to be verified with preclinical and clinical studies.

Corosolic acid and its structural analogs: A systematic review of their biological activities and underlying mechanism of action

BACKGROUND

The corosolic acid (CA), also known as plant insulin, is a pentacyclic triterpenoid extracted from plants such as Lagerstroemia speciosa. It has been shown to have anti-diabetic, anti-inflammatory and anti-tumor effects. Its structural analogs ursolic acid (UA), oleanolic acid (OA), maslinic acid (MA), asiatic acid (AA) and betulinic acid (BA) display similar individual pharmacological activities to those of CA. However, there is no systematic review documenting pharmacological activities of CA and its structural analogues. This study aims to fill this gap in literature.

PURPOSE

This systematic review aims to summarize the medical applications of CA and its analogues.

METHODS

A systematic review summarizes and compares the extraction techniques, pharmacokinetic parameters, and pharmacological effects of CA and its structural analogs. Hypoglycemic effect is one of the key inclusion criteria for searching Web of Science, PubMed, Embase and Cochrane databases up to October 2020 without language restrictions. 'corosolic acid', 'ursolic acid', 'oleanolic acid', 'maslinic acid', 'asiatic acid', 'betulinic acid', 'extraction', 'pharmacokinetic', 'pharmacological' were used to extract relevant literature. The PRISMA guidelines were followed.

RESULTS

At the end of the searching process, 140 articles were selected for the systematic review. Information of CA and five of its structural analogs including UA, OA, MA, AA and BA were included in this review. CA and its structural analogs are pentacyclic triterpenes extracted from plants and they have low solubilities in water due to their rigid scaffold and hydrophobic properties. The introduction of water-soluble groups such as sugar or amino groups could increase the solubility of CA and its structural analogs. Their biological activities and underlying mechanism of action are reviewed and compared.

CONCLUSION

CA and its structural analogs UA, OA, MA, AA and BA are demonstrated to show activities in lowering blood sugar, anti-inflammation and anti-tumor. Their oral absorption and bioavailability can be improved through structural modification and formulation design. CA and its structural analogs are promising natural product-based lead compounds for further development and mechanistic studies.

Size, shape, charge and "stealthy" surface: Carrier properties affect the drug circulation time in vivo

The present review sets out to discuss recent developments of the effects and mechanisms of carrier properties on their circulation time. For most drugs, sufficient in vivo circulation time is the basis of high bioavailability. Drug carrier plays an irreplaceable role in helping drug avoid being quickly recognized and cleared by mononuclear phagocyte system, to give drug enough time to arrive at targeted organ and tissue to play its therapeutic effect. The physical and chemical properties of drug carriers, such as size, shape, surface charge and surface modification, would affect their in vivo circulation time, metabolic behavior and biodistribution. The final circulation time of carriers is determined by the balance between macrophage recognitions, blood vessel penetration and urine excretion. Therefore, when designing the drug delivery system, we should pay much attention to the properties of drug carriers to get enough in vivo circulation time to arrive at target site eventually. This article mainly reviews the effect of carrier size, size, surface charge and surface properties on its circulation time in vivo, and discusses the mechanism of these properties affecting circulation time. This review has reference significance for the research of long-circulation drug delivery system.

Enhancement of the Antioxidant and Skin Permeation Properties of Betulin and Its Derivatives

This study investigated the antioxidant activity DPPH, ABTS, and Folin-Ciocalteu methods of betulin (compound 1) and its derivatives (compounds 2-11). Skin permeability and accumulation associated with compounds 1 and 8 were also examined. Identification of the obtained products (compound 2-11) and betulin isolated from plant material was based on the analysis of 1H- NMR and 13C-NMR spectra. The partition coefficient was calculated to determine the lipophilicity of all compounds. In the next stage, the penetration through pig skin and its accumulation in the skin were evaluated of ethanol vehicles containing compound 8 (at a concentration of 0.226 mmol/dm3), which was characterized by the highest antioxidant activity. For comparison, penetration studies of betulin itself were also carried out. Poor solubility and the bioavailability of pure compounds are major constraints in combination therapy. However, we observed that the ethanol vehicle was an enhancer of skin permeation for both the initial betulin and compound 8. The betulin 8 derivative showed increased permeability through biological membranes compared to the parent betulin. The paper presents the transformation of polycyclic compounds to produce novel derivatives with marked antioxidant activities and as valuable intermediates for the pharmaceutical industry. Moreover, the compounds contained in the vehicles, due to their mechanism of action, can have a beneficial effect on the balance between oxidants and antioxidants in the body, minimizing the effects of oxidative stress. The results of this work may contribute to knowledge regarding vehicles with antioxidant potential. The use of vehicles for this type of research is therefore justified.

Strategies for the design of nanoparticles: starting with long-circulating nanoparticles, from lab to clinic

Short half-life is one of the main causes of drug attrition in clinical development, which also leads to the failure of many leading compounds and hits to become drug candidates. Nowadays, nanomaterials have been applied to drug development to address this problem. In fact, the clinical application of nanoparticles (NPs) is severely limited due to their rapid elimination by the reticuloendothelial system (RES) in vivo. In this paper, we aim to summarize representative strategies on prolonging the circulation time for bridging the gap between excellent pharmaceutics and proper half-life and encourage clinical translation.

Prospects of Delivering Natural Compounds by Polymer-Drug Conjugates in Cancer Therapeutics

Synthetic chemotherapeutics have played a crucial role in minimizing mostly palliative symptoms associated with cancer; however, they have also created other problems such as system toxicity due to a lack of specificity. This has led to the development of polymer-drug conjugates amongst other novel drug delivery systems. Most of the formulations designed using delivery systems consist of synthetic drugs and face issues such as drug resistance, which has already rendered drugs such as antibiotics ineffective. This is further exacerbated by toxicity due to long term use. Given these problems and the fact that conjugation of synthetic compounds to polymers has been relatively slow with no formulation on the market after a decade of extensive studies, the focus has shifted to using this platform with medicinal plant extracts to improve solubility, specificity and increase drug release of medicinal and herbal bioactives. In recent years, various plant extracts such as flavonoids, tannins and terpenoids have been studied extensively using this approach. The success of formulations developed using novel drug-delivery systems is highly dependent on the tumour microenvironment especially on the enhanced permeability and retention effect. As a result, the compromised lymphatic network and 'leaky' vasculature exhibited by tumour cells act as a guiding principle in the delivering of these formulations. This review focuses on the state of the polymer-drug conjugates and their exploration with natural compounds, the progress and difficulties thus far, and future directions concerning cancer treatment.

Impacts of particle size on the cytotoxicity, cellular internalization, pharmacokinetics and biodistribution of betulinic acid nanosuspensions in combined chemotherapy

To evaluate the effect of particle size on the cellular internalization, tissue distribution, and bioavailability of betulinic acid nanosuspensions (BA/NSs) and further investigate the combined effect of BA/NSs and Taxol® on breast cancer, BA/NSs with different particle sizes (160 nm, 400 nm, and 700 nm) were prepared by an efficient universal green technology. The use of BA/NS (160 nm) was more likely to increase the BA release rate and enhance bioavailability compared with the use of larger size particles. BA/NSs were internalized by 4T1 cells in different ways, including clathrin-mediated endocytosis, caveolae-mediated endocytosis, and macropinocytosis. For the 4T1 orthotopic tumor model, BA/NS (160 nm) showed a tendency to accumulate at a higher level in tumor tissue. Moreover, combination therapy with BA/NSs and Taxol® showed remarkable potential to enhance antitumor activity in vitro and in vivo. The cytotoxicity and apoptotic ability of the different preparations decreased in the following order: BA/NS (160 nm) + Taxol®, BA/NS (400 nm) + Taxol®, and BA/NS (700 nm) + Taxol®. The tumor inhibition rates of BA/NSs (160 nm, 400 nm, and 700 nm) combined with Taxol® were 2.35-, 1.74- and 1.12-fold higher than that of free BA, respectively. The combined chemotherapy showed good safety, indicating that it had the effect of enhancing treatment and reducing toxicity.

Synthesis of Gelatin-Based Dual-Targeted Nanoparticles of Betulinic Acid for Antitumor Therapy

Betulinic acid (BA) is a natural antitumor agent and has biological activity against multiple human tumor cell lines with low cytotoxicity to normal cells, while the high hydrophobicity and the short half-life of this compound limit its clinical application. Here, gelatin-based dual-targeted nanoparticles of BA are promising to solve this problem. Hydrophobic BA is loaded in cyclodextrin to increase its solubility and prolong the circulation time in vivo. The nanoscale drug delivery systems can further enhance the bioavailability and the antitumor effect of BA and are passively targeted to the tumor tissue sites by enhanced permeability and retention effect. The RGD sequence of gelatin specifically recognizes tumor cells and brings agents into tumor cells. The nanoparticles were characterized by transmission electron microscopy, Fourier transform infrared, nuclear magnetic resonance, etc. In addition, we observed antitumor activity of the nanoparticles using both cell-based assays and mouse xenograft tumors, which proved that betulinic acid/gelatin-γ-cyclodextrin nanoparticles had a better tumor inhibition effect than betulinic acid/γ-cyclodextrin inclusion compound.

Betulinic Acid and Brosimine B Hybrid Derivatives as Potential Agents against Female Cancers

Background:

Cancer is a multifactorial disease, representing one of the leading causes of death worldwide. On a global estimate, breast cancer is the most frequently occurring cancer in women and cervical cancer, the fourth most common. Both types of cancer remain the major cause of cancer-related mortality in developing countries. A strategy for rational drug design is hybridization, which aims to bring together in one molecule, two or more pharmacophores in order to reach several biological targets.

Objective:

The objective of this work was to develop new hybrids based on natural pharmacophores: Betulinic acid (1) and brosimine b (2), active in female cancer cell lines.

Methods:

The coupling reactions were carried out by Steglich esterification. Different compounds were designed for the complete and simplified structural hybridization of molecules. The anticancer activities of the compounds were evaluated in human cervical adenocarcinoma (HeLa), human cervical metastatic epidermoid carcinoma (ME-180), and human breast adenocarcinoma (MCF-7) cell lines.

Results:

Hybrid 3 presented higher potency (IC50 = 9.2 ± 0.5μM) and SI (43.5) selectively in MCF-7 cells (in relation to Vero cells) with its cytotoxic effect occurring via apoptosis. In addition, compound 6 showed activity in MCF-7 and HeLa cells with intermediate potency, but with high efficacy, acting via apoptosis as well.

Conclusion:

In this context, we showed that the combination of two complex structures generated the development of hybrids with differing inhibitory profiles and apoptotic modes of action, thus representing potential alternatives in female cancer treatment.

A Comparative Investigation of the Ability of Various Aptamer-Functionalized Drug Nanocarriers to Induce Selective Apoptosis in Neoplastic Hepatocytes: In Vitro and In Vivo Outcome

Aptamers offer a significant promise to target various cancers including hepatocellular carcinoma (HCC), for their high affinity and ability to reach the target site(s), non-immunogenicity, and low cost. The targeting ability to neoplastic hepatocytes by the aptamer, TLS 9a with phosphorothioate backbone modification (designated as L5), has not been explored yet. Hence, we investigated the comparative potential of L5 with some other previously reported liver cancer cell-specific aptamers, conjugated on the surface of drug-nanocarriers. Various in vitro studies such as cytotoxicity, in vitro cellular uptake, cell cycle analysis, and investigations related to apoptosis were performed. In vivo studies carried out here include macroscopic and microscopic hepatic alterations in chemically induced hepatocarcinogenesis in rats, upon experimental treatments. The outcome of the investigations revealed that L5-functionalized drug-nanocarrier (PTX-NPL5) had the highest apoptotic potential compared with the other aptamer-conjugated experimental formulations. Further, its maximum internalization by neoplastic hepatocytes and minimum internalization by normal hepatocytes indicate that it had the potential to preferentially target the neoplastic hepatocytes. Data of in vivo studies revealed that PTX-NPL5 reduced tumor incidences and tumor progress. Superior potency of PTX-NPL5 may be due to the maximum affinity of L5 towards neoplastic hepatocytes resulting in maximum permeation of drug-nanocarrier in them. An effective site-specific targeting of neoplastic hepatocytes can be achieved by L5 for preferential delivery of therapeutics. Further, investigations are needed to identify the target protein(s) on neoplastic hepatocytes responsible for ligand-receptor interaction of L5.

Aptamer-Functionalized Drug Nanocarrier Improves Hepatocellular Carcinoma toward Normal by Targeting Neoplastic Hepatocytes

Site-specific delivery of chemotherapeutics specifically to neoplastic hepatocytes without affecting normal hepatocytes should be a focus for potential therapeutic management of hepatocellular carcinoma (HCC). The aptamer TLS 9a with phosphorothioate backbone modifications (L5) has not been explored so far for preferential delivery of therapeutics in neoplastic hepatocytes to induce apoptosis. Thus, the objective of the present investigation was to compare the therapeutic potential of L5-functionalized drug nanocarrier (PTX-NPL5) with those of the other experimental drug nanocarriers functionalized by previously reported HCC cell-targeting aptamers and non-aptamer ligands, such as galactosamine and apotransferrin. A myriad of well-defined investigations such as cell cycle analysis, TUNEL (terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate nick end labeling) assay, and studies related to apoptosis, histopathology, and immunoblotting substantiated that PTX-NPL5 had the highest potency among the different ligand-attached experimental formulations in inducing selective apoptosis in neoplastic hepatocytes via a mitochondrial-dependent apoptotic pathway. PTX-NPL5 did not produce any notable toxic effects in healthy hepatocytes, thus unveiling a new and a safer option in targeted therapy for HCC. Molecular modeling study identified two cell-surface biomarker proteins (tumor-associated glycoprotein 72 [TAG-72] and heat shock protein 70 [HSP70]) responsible for ligand-receptor interaction of L5 and preferential internalization of PTX-NPL5 via clathrin-mediated endocytosis in neoplastic hepatocytes. The potential of PTX-NPL5 has provided enough impetus for its rapid translation from the pre-clinical to clinical domain to establish itself as a targeted therapeutic to significantly prolong survival in HCC.

Enhancing Betulinic Acid Dissolution Rate and Improving Antitumor Activity via Nanosuspension Constructed by Anti-Solvent Technique

Purpose

The aim of this study was to prepare and evaluate betulinic acid nanosuspension (BA-NS) for new drug delivery to enhance its solubility and in vitro anti-tumor activity.

Methods

BA-NS was formulated by an anti-solvent precipitation method using the Box-Behnken design (BBD). Particle size (PS) and Zeta potential were measured by laser particle size analysis. The drug solid state after freeze drying was characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD) and Fourier transform infrared spectroscopy (FTIR) after freeze drying. The saturation solubility and dissolution rate were determined by solubility assay and in vitro dissolution studies, respectively. The in vitro cytotoxicity assay was performed using 3-(4,5-dimethylthiazole)-2,5-diphenltetraazolium bromide (MTT) method.

Results

The PS was 129.7±12.2 nm having a Zeta potential of −28.1±4.5 mV and the polydispersity index (PDI) was 0.231±0.013, which confirmed that the nanosuspension was in the stable amorphous state. A series of characterization experiments demonstrated that nanoparticles retained original effective structure and existed as spherical or near-spherical nanoparticles in the nanosuspension, but the drug transferred from the crystal state to the amorphous state. The form of lyophilized BA-NS was very successful in enhancing the dissolution rate in PH-dependent way. The cytotoxicity assay revealed that BA-NS could significantly enhance the in vitro anti-proliferation against tumor cells compared to the BA suspension (BA-S).

Conclusion

The BA-NS can remarkably improve solubility and in vitro antitumor activity, which seems very promising for the treatment of cancers in practical application.

In vivo antitumour properties of tribenzyltin carboxylates in a 4T1 murine metastatic mammary tumour model: Enhanced efficacy by PLGA nanoparticles

This study reports the in vivo performance of two tribenzyltin carboxylate complexes, tri(4-fluorobenzyl)tin[(N,N-diisopropylcarbamothioyl)sulfanyl]acetate (C1) and tribenzyltin isonicotinate (C9), in their native form as well as in a poly(lactic-co-glycolic acid) (PLGA)-based nanoformulation, to assess their potential to be translated into clinically useful agents. In a 4T1 murine metastatic mammary tumour model, single intravenous administration of C1 (2.7 mg/kg) and C9 (2.1 mg/kg; 2.1 mg/kg C9 is equivalent to 2.7 mg/kg C1) induced greater tumour growth delay than cisplatin and doxorubicin at equivalent doses, while a double-dose regimen demonstrated a much greater tumour growth delay than the single-dose treated groups. To improve the efficacy of the complexes in vivo, C1 and C9 were further integrated into PLGA nanoparticles to yield nanosized PLGA-C1 (183.7 ± 0.8 nm) and PLGA-C9 (163.2 ± 1.2 nm), respectively. Single intravenous administration of PLGA-C1 (2.7 mg C1 equivalent/kg) and PLGA-C9 (2.1 mg C9 equivalent/kg) induced greater tumour growth delay (33% reduction in the area under curve compared to that of free C1 and C9). Multiple-dose administration of PLGA-C1 (5.4 mg C1 equivalent/kg) and PLGA-C9 (4.2 mg C9 equivalent/kg) induced tumour growth suppression at the end of the study (21.7 and 34.6% reduction relative to the size on day 1 for the double-dose regimen; 73.5 and 79.0% reduction relative to the size on day 1 for the triple-dose regimen, respectively). Such tumour growth suppression was not observed in mice receiving multiple-dose regimens of free C1 and C9. Histopathological analysis revealed that metastasis to the lung and liver was inhibited in mice receiving PLGA-C1 and PLGA-C9. The current study has demonstrated the improved in vivo antitumour efficacies of C1 and C9 compared with conventional chemotherapy drugs and the enhancement of the efficacies of these agents via a robust PLGA-based nanoformulation and multiple-drug administration approach.

Comparative analysis between four model nanoformulations of amphotericin B-chitosan, amphotericin B-dendrimer, betulinic acid-chitosan and betulinic acid-dendrimer for treatment of Leishmania major: real-time PCR assay plus

Background

Amphotericin B (Amp) and Betulinic acid (BA) as antileishmanial agents have negligible water solubility and high toxicity. To solve these problems, for the first time, chitosan nanoparticles and Anionic Linear Globular Dendrimer (D) were synthesized for the treatment of Leishmania major (L. major).

Method

Chitosan and dendrimer nanoparticles were synthesized, and Amp and BA were loaded into the nanoparticles. The particles were then characterized using various methods and their efficacy was evaluated in vitro and in vivo environments (parasite burden was confirmed using pathological studies and real-time PCR methods).

Result

The results of docking showed that Amp and BA can be loaded into chitosan and dendrimer nanoparticles. The results of physically drug loading efficiency for AK (Amphotericin B-chitosan), BK (Betulinic acid-chitosan), AD (Amphotericin B-Dendrimer) and BD (Betulinic acid- Dendrimer) were 90, 93, 84 and 96 percent, respectively. The characterization results indicated that the drugs were loaded into nanoparticles physically. Moreover, the increased solubility rate for AD=478, BD=790, AK=80 and BK=300 folds. Furthermore, the results of the drug delivery system showed the slow controlled drug release pattern with cellular uptake of more than 90%. The treatment results showed a 100 percent decrease of toxicity for the all nanodrugs was observed in vivo and in vitro environments. Moreover, AK10 and BK20 mg/kg reduced parasite burden by 83 percent (P<0.001), while AD50 and BD40 mg/kg reduced it to a lesser extent compared to glucantime.

Conclusion

All the synthesized nanodrugs were completely succeeded by 100% to recovery the L. major induced pathological effects in the infected footpad. Also, the results of present study were confirmed with real-time PCR and the results showed that AK and BK were succeeded in a large extent to the treatment of L. major infection (P<0.001), therefore AK and BK could be considered as proper alternatives of choices drugs.

Betulinic acid, derived from the desert lavender Hyptis emoryi, attenuates paclitaxel-, HIV-, and nerve injury-associated peripheral sensory neuropathy via block of N- and T-type calcium channels

The Federal Pain Research Strategy recommended development of nonopioid analgesics as a top priority in its strategic plan to address the significant public health crisis and individual burden of chronic pain faced by >100 million Americans. Motivated by this challenge, a natural product extracts library was screened and identified a plant extract that targets activity of voltage-gated calcium channels. This profile is of interest as a potential treatment for neuropathic pain. The active extract derived from the desert lavender plant native to southwestern United States, when subjected to bioassay-guided fractionation, afforded 3 compounds identified as pentacyclic triterpenoids, betulinic acid (BA), oleanolic acid, and ursolic acid. Betulinic acid inhibited depolarization-evoked calcium influx in dorsal root ganglion (DRG) neurons predominantly through targeting low-voltage-gated (Cav3 or T-type) and CaV2.2 (N-type) calcium channels. Voltage-clamp electrophysiology experiments revealed a reduction of Ca, but not Na, currents in sensory neurons after BA exposure. Betulinic acid inhibited spontaneous excitatory postsynaptic currents and depolarization-evoked release of calcitonin gene-related peptide from lumbar spinal cord slices. Notably, BA did not engage human mu, delta, or kappa opioid receptors. Intrathecal administration of BA reversed mechanical allodynia in rat models of chemotherapy-induced peripheral neuropathy and HIV-associated peripheral sensory neuropathy as well as a mouse model of partial sciatic nerve ligation without effects on locomotion. The broad-spectrum biological and medicinal properties reported, including anti-HIV and anticancer activities of BA and its derivatives, position this plant-derived small molecule natural product as a potential nonopioid therapy for management of chronic pain.

Betulin and its derivatives as novel compounds with different pharmacological effects

Betulin (B) and Betulinic acid (BA) are natural pentacyclic lupane-structure triterpenoids which possess a wide range of pharmacological activities. Recent evidence indicates that B and BA have several properties useful for the treatment of metabolic disorders, infectious diseases, cardiovascular disorders, and neurological disorders. In the current review, we discuss B and BA structures and derivatives and then comprehensively explain their pharmacological effects in relation to various diseases. We also explain antiviral, antibacterial and anti-cancer effects of B and BA. Finally, we discuss the delivery methods, in which these compounds most effectively target different systems.

Gemcitabine and betulinic acid co-encapsulated PLGA-PEG polymer nanoparticles for improved efficacy of cancer chemotherapy

The present study demonstrated the development of gemcitabine and betulinic acid co-encapsulated PLGA-PEG polymer nanoparticles for enhancing the chemotherapeutic response. This combinatorial PLGA-PEG nanoparticle was formulated using double emulsion and had size <200 nm. The developed nanoparticles were characterized using dynamic light scattering and transmission electron microscopy for their size and shape, respectively. The in vitro release of the drugs from combinatorial nanoparticles was predominantly followed by Fickian diffusion phenomenon. Study on hemocompatibilty approved the administration of this combinatorial nanoparticle for animal study. In vitro cytotoxicity study on Panc1 cells using MTT assay, reactive oxygen species production and cellular apoptotic assay demonstrated that combinatorial nanoparticle was more cytotoxic compared to native drugs solution. Furthermore, the combinatorial nanoparticle suppressed tumor growth more efficiently in Ehrlich (solid) tumor model than the native gemcitabine and betulinic acid at the same concentrations. These findings indicated that PLGA-PEG nanoparticle might be used to co-deliver multiple chemotherapeutic drugs with different properties for enhancing antitumor efficacy.

Biotin-Modified Polylactic- co-Glycolic Acid Nanoparticles with Improved Antiproliferative Activity of 15,16-Dihydrotanshinone I in Human Cervical Cancer Cells

15,16-Dihydrotanshinone I (DI), a natural compound isolated from a traditional Asian functional food Salvia Miltiorrhiza Bunge, is known for its anticancer activity. However, poor solubility of DI limits its desirable anticancer application. Herein, polylactic- co-glycolic acid (PLGA) was functionalized with polyethylene glycol (PEG) and biotin to form copolymers PEG-PLGA (PPA) and biotin-PEG-PLGA (BPA). DI was encapsulated in copolymers PPA and BPA to obtain DI-PPA-NPs (NPs = nanoparticles) and DI-BPA-NPs, respectively. The particle size and its distribution, encapsulation efficiency, and in vitro releasing capacity of DI-BPA-NPs were characterized by biophysical methods. MTT assay was used to evaluate the antiproliferative activity of free DI, DI-PPA-NPs, and DI-BPA-NPs in human cervical cancer Hela cells. DI-BPA-NPs showed the highest cytotoxicity on Hela cells with an IC₅₀ value of 4.55 ± 0.631 μM, while it was 8.20 ± 0.849 and 6.14 ± 0.312 μM for DI and DI-PPA-NPs in 72 h, respectively. The superior antiproliferative activity was supported by the fact that DI-BPA-NPs could be preferentially internalized by Hela cells, owing to their specific interaction between biotin and overexpressed biotin receptors. In addition, DI-BPA-NPs effectively inhibited Hela cell proliferation by inducing G2/M phase cycle arrest and decreasing the intracellular reactive oxygen species (ROS) level by 31.50 ± 2.29% in 5 min. In summary, DI-BPA-NPs shows improved antiproliferative activity against human cervical cancer as comparing with free DI, demonstrating its application potential in cancer therapy.

Novel Nanosized Chitosan-Betulinic Acid Against Resistant Leishmania Major and First Clinical Observation of such parasite in Kidney

Regarding the antiparasitic effects of Betulinic acid (B) against Leishmaniasis, it was loaded into nanochitosan (K) for the first time in order to improve its therapeutic effects and decrease its side effects for the treatment of Leishmania major-infected Balb/c mice. Improvement the therapeutic efficacy of Bas an anti-leishmania agent through increasing the effective dose was achieved by using a novel solvent and phase separation method for K synthesis. The synthesized K with the size of 102 nm and Betulinic acid-nanochitosan (BK) with the size of 124 nm and drug loading efficiency of 93%, cellular uptake of 97.5% with the slow drug release pattern was prepared. To increase the therapeutic dose, a modified 10% acetic acid solvent was used. The in vitro and in vivo results showed that the nanodrug of BK was non toxic by 100% and BK20 mg/kg could completely performed the wound healing and inhibit the parasite in a large extent (P ˂ 0.001) compared to other groups. Therefore, BK could be considered as an alternative regimen for treatment of L. major.

Tanshinol borneol ester on nanostructured lipid carriers has longer brain and systemic effector retention and better antioxidant activity in vivo

Background

Tanshinol borneol ester (DBZ) is a hybrid of danshensu (DSS) and borneol and has anti-ischemic activity in animals. However, its low water solubility and short half-life limit its clinical application.

Methods

We prepared polyethylene glycol (PEG)-modified and DBZ-loaded nanostructured lipid carriers (DBZ-PEG-NLC) and DBZ-NLC, and examined their physical characteristics, such as particle size, zeta potential, entrapment efficiency and drug loading. The in vitro stability and pharmacokinetics in rats as well as antioxidant activity of DBZ-PEG-NLC and DBZ-NLC in a C57BL/6 mouse model of ischemia/reperfusion-related brain injury were investigated. The levels of DBZ and its hydrolyzed DSS in rat plasma and brain microdialysates were determined by liquid chromatography-mass spectroscopy/mass spectroscopy analysis.

Results

We found that the mean particle size and entrapment efficacy of DBZ-PEG-NLC were similar to that of DBZ-NLC. The DBZ-PEG-NLC, like DBZ-NLC, released DBZ in a biphasic manner with initially burst release and then prolonged slow release in vitro. Intravenous injection of DBZ-PEG-NLC resulted in significantly higher levels and longer retention periods of DBZ and DSS in plasma and the brains than DBZ-NLC and DBZ in rats. Finally, treatment with DBZ-PEG-NLC achieved a better antioxidant activity than DBZ or DBZ-NLC in mouse model of ischemia/reperfusion by reducing the levels of brain malondialdehyde, but increasing the levels of brain superoxide dismutase and glutathione.

Conclusion

DBZ-PEG-NLC is a preferable option to deliver DBZ for sustainable release of DSS and borneol in vivo, and may serve as a promising drug for effective therapy of ischemic cardiovascular and cerebrovascular diseases.

Therapeutic applications of betulinic acid nanoformulations

Betulinic acid (BA), a naturally occurring plant-derived pentacyclic triterpenoid, has gained attention in recent years owing to its broad-spectrum biological and medicinal properties. Despite the pharmacological activity of BA, it has been associated with some drawbacks, such as poor aqueous solubility and short half-life in vivo, which limit therapeutic application. To solve these problems, much work in recent years has focused on enhancing BA's aqueous solubility, half-life, and efficacy by using nanoscale drug delivery systems. Several different kinds of nanoscale delivery systems-including polymeric nanoparticles, magnetic nanoparticles, liposomes, polymeric conjugates, nanoemulsions, cyclodextrin complexes, and carbon nanotubes-have been developed for the delivery of BA. Here, we focus on the recent developments of novel nanoformulations used to deliver BA in order to improve its efficacy.