Minicapsules encapsulating nanoparticles for targeting, apoptosis induction and treatment of colon cancer

Exploring the potential of pH-sensitive polymers in targeted drug delivery

The pH-sensitive polymers have attained significant attention in the arena of targeted drug delivery (TDD) because of their exceptional capability to respond to alteration in pH in various physiological environments. This attribute aids pH-sensitive polymers to act as smart carriers for therapeutic agents, transporting them precisely to target locations while curtailing the release of drugs in off-targeted sites, thereby diminishing side effects. Many pH-responsive polymers in TDD have revealed promising results, with increased therapeutic efficacy and decreased toxic effects. Several pH-sensitive polymers, including, hydroxy-propyl-methyl cellulose, poly (methacrylic acid) (Eudragit series), poly (acrylic acid), and chitosan, have been broadly studied for their myriad applications in the management of various types of diseases. Additionally, the amalgamation of pH-sensitive polymers with, additive manufacturing techniques like 3D printing, has resulted in the progression of novel drug delivery systems that regulate drug release in a controlled manner. Herein, types of pH-sensitive polymers in TDD are systemically reviewed. We have briefly discussed the nanocarriers employed for the delivery of various pH-sensitive polymers in TDD. Finally, miscellaneous applications of pH-sensitive polymers are discussed thoroughly with special attention to the implication of 3D printing in pH-sensitive polymers.

Impact of Macrophages on the Interaction of Cetuximab-Functionalized Polyelectrolyte Capsules with EGFR-Expressing Cancer Cells

Polyelectrolyte capsules (PCs) are a promising tool for anticancer drug delivery and tumor targeting. Surface functionalization of PCs with antibodies is widely used for providing their specific interactions with cancer cells. The efficiency of PC-based targeted delivery systems can be affected by the cellular heterogeneity of the tumor, particularly by the presence of tumor-associated macrophages. We used human epidermoid carcinoma cells and macrophages derived from human leukemia monocytic cells in either monoculture or coculture to analyze the targeting capacity and internalization efficiency of PCs with a mean size of 1.03 ± 0.11 μm. The PCs were functionalized with the monoclonal antibody cetuximab targeting the human epidermal growth factor receptor (EGFR). We have shown that surface functionalization of the PCs with cetuximab ensures a specific interaction with EGFR-expressing cancer cells and promotes capsule internalization. In monoculture, the macrophages derived from human leukemia monocytic cells have been found to internalize both nonfunctionalized PCs and cetuximab-functionalized PCs (Cet-PCs) more intensely compared to epidermoid carcinoma cells. The internalization of Cet-PCs by cancer cells is mediated by lipid rafts of the cell membrane, whereas the PC internalization by macrophages is only slightly influenced by lipid rafts. Experiments with a coculture of human epidermoid carcinoma cells and macrophages derived from human leukemia monocytic cells have shown that Cet-PCs preferentially interact with cancer cells, which are subsequently attacked by macrophages. These data can be used to further improve the strategy of PC functionalization for targeted delivery, with the cellular heterogeneity of the tumor microenvironment taken into consideration.

Exploring cytotoxicity of cordycepin loaded nanovesicles against (HCT116) colon cancer cells: Optimization and cellular evaluation

Numerous researchers have investigated cordycepin (COR) as an anti-tumor compound. COR has been documented to have cytotoxic effects on several cancer cells. The current work used a Box-Behnken mathematical design to minimize COR's size. The design incorporated COR concentration, phospholipid concentration and sonication time as variables to minimize the vesicles of COR emulsomes (COR-EMLs). To evaluate degree of improvement of COR cytotoxicity against colorectal cancer (HCT116) cells, cell viability, cell cycle analysis and apoptosis have been assessed. In addition, wound scratching and mitochondrial membrane potential were evaluated. Results of Box-Behnken design achieved COR-EMLs sizes in range from 91.54 ± 2.3-343.83 ± 3.7 nm. Moreover, the optimized formula morphology's was evaluated using transmission electron microscope and showed nanospheres in range of 100 nm. COR released from COR-EMLs exceeded 80% after 12 h.The half-maximal inhibitory concentration (IC50) of the refined COR-EML formula was about four times lower than that of COR-raw. The cell cycle study revealed that administration of COR-EML considerably hindered HCT116 cellular propagation in contrast to plain emulsomes (EMLs) and COR-raw with a denser cell compilation in G2/M. Moreover, the optimized formula notably enhanced the proportion of cells in both the initial and late phases of apoptosis. The augmentation of COR cytotoxicity was confirmed by its inhibition of cancer cell wound healing by approximately 40%. The mitochondrial membrane potential was significantly lower than in cells treated with COR-raw and EMLs. Finally, loading COR into the EMLs increased COR's capacity to lower mitochondrial membrane functionality and significantly improved its cytotoxicity.

Emerging nanotechnology-based therapeutics to combat multidrug-resistant cancer

Cancer often develops multidrug resistance (MDR) when cancer cells become resistant to numerous structurally and functionally different chemotherapeutic agents. MDR is considered one of the principal reasons for the failure of many forms of clinical chemotherapy. Several factors are involved in the development of MDR including increased expression of efflux transporters, the tumor microenvironment, changes in molecular targets and the activity of cancer stem cells. Recently, researchers have designed and developed a number of small molecule inhibitors and derivatives of natural compounds to overcome various mechanisms of clinical MDR. Unfortunately, most of the chemosensitizing approaches have failed in clinical trials due to non-specific interactions and adverse side effects at pharmacologically effective concentrations. Nanomedicine approaches provide an efficient drug delivery platform to overcome the limitations of conventional chemotherapy and improve therapeutic effectiveness. Multifunctional nanomaterials have been found to facilitate drug delivery by improving bioavailability and pharmacokinetics, enhancing the therapeutic efficacy of chemotherapeutic drugs to overcome MDR. In this review article, we discuss the major factors contributing to MDR and the limitations of existing chemotherapy- and nanocarrier-based drug delivery systems to overcome clinical MDR mechanisms. We critically review recent nanotechnology-based approaches to combat tumor heterogeneity, drug efflux mechanisms, DNA repair and apoptotic machineries to overcome clinical MDR. Recent successful therapies of this nature include liposomal nanoformulations, cRGDY-PEG-Cy5.5-Carbon dots and Cds/ZnS core–shell quantum dots that have been employed for the effective treatment of various cancer sub-types including small cell lung, head and neck and breast cancers.

Structure-function relationships in polymeric multilayer capsules designed for cancer drug delivery

The targeted delivery of cancer drugs to tumor-specific molecular targets represents a major challenge in modern personalized cancer medicine. Engineering of micron and submicron polymeric multilayer capsules allows the obtaining of multifunctional theranostic systems serving as controllable stimulus-responsive tools with a high clinical potential to be used in cancer therapy and detection. The functionalities of such theranostic systems are determined by the design and structural properties of the capsules. This review (1) describes the current issues in designing cancer cell-targeting polymeric multilayer capsules, (2) analyzes the effects of the interactions of the capsules with the cellular and molecular constituents of biological fluids, and (3) presents the key structural parameters determining the effectiveness of capsule targeting. The influence of the morphological and physicochemical parameters and the origin of the structural components and surface ligands on the functional activity of polymeric multilayer capsules at the molecular, cellular, and whole-body levels are summarized. The basic structural and functional principles determining the future trends of theranostic capsule development are established and discussed.

Nicotinamide and ascorbic acid nanoparticles against the hepatic insult induced in rats by high fat high fructose diet: A comparative study

AIMS

Non-alcoholic fatty liver disease (NAFLD) caused by consumption of high levels of fat and sugars (HFHS) in diet is considered one of the most dangerous medical complications among children and adolescents. Nicotinamide is among the promising candidates in ameliorating HFHS diet-induced NAFLD, but its use is limited by the possibility of prompting hepatotoxicity in high doses. Ascorbic acid is another promising candidate, however its use as a hepatoprotective agent is limited by its chemical instability. Therefore, the aim of the study was to overcome their delivery limitations and enhance their hepatoprotective activity by loading into nanoparticles.

KEY FINDINGS

In the present study, upon incorporating nicotinamide or ascorbic acid in chitosan nanoparticles, they ameliorated the insulin-resistant status induced in rats by a high-fat-high-fructose (HFHF) diet. Both formulae decreased serum level of ALT and AST, as well as liver tissue total cholesterol, triglycerides and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels. They also decreased oxidative and nitrosative stresses along with a significant increase in the hepatocellular energy. The biochemical findings were further confirmed by histopathological examination. Finally from the obtained data it could be concluded that chitosan nicotinamide nanoparticles at a dose level (10 mg/kg, p.o.) demonstrated beneficial pharmacological effect with safer toxicity profile than chitosan ascorbic acid nanoparticles.

SIGNIFICANCE

Nicotinamide chitosan nanoparticles could be recommended as daily supplement in the recovery from NAFLD.

Chitosan-Based Microparticles Enhance Ellagic Acid's Colon Targeting and Proapoptotic Activity

This study aimed at improving the targeting and cytotoxic effect of ellagic acid (EA) on colon cancer cells. EA was encapsulated in chitosan (CHIT) polymers then coated by eudragit S100 (ES100) microparticles. The release of EA double-coated microparticles (MPs) was tested at simulative pH values. Maximum release was observed at 24 h and pH 7.4. The cytotoxicity of EA MPs on HCT 116 colon cancer cells was synergistically improved as compared with raw EA. Cell-cycle analysis by flow cytometry suggested enhanced G2-M phase colon cancer cell accumulation. In addition, a significantly higher cell fraction was observed in the pre-G phase, which highlighted the enhancement of the proapoptotic activity of EA formulated in the double-coat mixture. Annexin-V staining was used for substantiation of the observed cell-death-inducing activity. Cell fractions were significantly increased in early, late, and total cell death. This was backed by high elevation in cellular content of caspase 3. Effectiveness of the double-coated EA to target colonic tissues was confirmed using real-time iohexol dye X-ray radiography. In conclusion, CHIT loaded with EA and coated with ES100 formula exhibits improved colon targeting as well as enhanced cytotoxic and proapoptotic activity against HCT 116 colon cancer when compared with the administration of raw EA.

Optimized Ellagic Acid-Ca Pectinate Floating Beads for Gastroprotection against Indomethacin-Induced Gastric Injury in Rats

A peptic ulcer is an alimentary tract injury that leads to a mucosal defect reaching the submucosa. This work aimed to optimize and maximize ellagic acid (EA) loading in Ca pectinate floating beads to maximize the release for 24 h. Three factors were selected: Ca pectinate concentration (X1, 1–3 w/v %), EA concentration (X2, 1–3 w/v %) and the dropping time (X3, 10–30 min). The factorial design proposed eight formulations. The optimized EA–Ca pectinate formulation was evaluated for the gastric ulcer index and the oxidative stress parameter determination of gastric mucosa. The results indicated that the optimum EA–Ca pectinate formula significantly improved the gastric ulcer index in comparison with raw EA. The protective effect of the optimized EA–Ca pectinate formula was further indicated by the histopathological features of the stomach. The results of the study indicate that an EA formulation in the form of Ca pectinate beads would be effective for protection against gastric ulcers because of Nonsteroidal anti-inflammatory drugs (NSAID) administration.

Nanoparticles in Colorectal Cancer Therapy: Latest In Vivo Assays, Clinical Trials, and Patents

Colorectal cancer (CRC) is the third most common cancer worldwide. Its poor response to current treatment options in advanced stages and the need for efficient diagnosis in early stages call for the development of new therapeutic and diagnostic strategies. Some of them are based on the use of nanometric materials as carriers and releasers of therapeutic agents and fluorescent molecules, or even on the utilization of magnetic materials that provide very interesting properties. These nanoformulations present several advantages compared with the free molecular cargo, including increased drug solubility, bioavailability, stability, and tumor specificity. Moreover, tumor multidrug resistance has been decreased in some cases, leading to improved treatment effectiveness by reducing drug dose and potential side effects. Here, we present an updated overview of the latest advances in clinical research, in vivo studies, and patents regarding the application of nanoformulations in the treatment of CRC. Based on the information gathered, a wide variety of nanomaterials are being investigated in clinical research, even in advanced phases, i.e., close to reaching the market. In sum, these novel materials can offer remarkable advantages with respect to current therapies, which could be complemented or even replaced by these nanosystems in the near future.