Interactions between selected bile salts and Triton X-100 or sodium lauryl ether sulfate

Decellularized extracellular matrix-based bioengineered 3D breast cancer scaffolds for personalized therapy and drug screening

Breast cancer (BC) is the second deadliest cancer after lung cancer. Similar to all cancers, it is also driven by a 3D microenvironment. The extracellular matrix (ECM) is an essential component of the 3D tumor micro-environment, wherein it functions as a scaffold for cells and provides metabolic support. BC is characterized by alterations in the ECM. Various studies have attempted to mimic BC-specific ECMs using artificial materials, such as Matrigel. Nevertheless, research has proven that naturally derived decellularized extracellular matrices (dECMs) are superior in providing the essential in vivo-like cues needed to mimic a cancer-like environment. Developing in vitro 3-D BC models is not straightforward and requires extensive analysis of the data established by researchers. For the benefit of researchers, in this review, we have tried to highlight all developmental studies that have been conducted by various scientists so far. The analysis of the conclusions drawn from these studies is also discussed. The advantages and drawbacks of the decellularization methods employed for generating BC scaffolds will be covered, and the review will shed light on how dECM scaffolds help develop a BC environment. The later stages of the article will also focus on immunogenicity issues arising from decellularization and the origin of the tissue. Finally, this review will also discuss the biofabrication of matrices, which is the core part of the bioengineering process.

Self-assembly of bile salts and their mixed aggregates as building blocks for smart aggregates

The present communication offers a comprehensive overview of the self-assembly of bile salts emphasizing their mixed smart aggregates with a variety of amphiphiles. Using an updated literature survey, we have explored the dissimilar interactions of bile salts with different types of surfactants, phospholipids, ionic liquids, drugs, and a variety of natural and synthetic polymers. While assembling this review, special attention was also provided to the potency of bile salts to alter the size/shape of aggregates formed by several amphiphiles to use these aggregates for solubility improvement of medicinally important compounds, active pharmaceutical ingredients, and also to develop their smart delivery vehicles. A fundamental understanding of bile salt mixed aggregates will enable the development of new strategies for improving the bioavailability of drugs solubilized in newly developed potential hosts and to formulate smart aggregates of desired morphology for specific targeted applications. It enriches our existing knowledge of the distinct interactions exerted in mixed systems of bile salts with variety of amphiphiles. By virtue of this, researchers can get innovative ideas to construct novel nanoaggregates from bile salts by incorporating various amphiphiles that serve as a building block for smart aggregates for their numerous industrial applications.

Interaction of TX-100 and Antidepressant Imipramine Hydrochloride Drug Mixture: Surface Tension, 1H NMR, and FT-IR Investigation

Interfacial interaction amongst the antidepressant drug-imipramine hydrochloride (IMP) and pharmaceutical excipient (triton X-100 (TX-100-nonionic surfactant)) mixed system of five various ratios in dissimilar media (H₂O/50 mmol·kg⁻¹ NaCl/250 mmol·kg⁻¹ urea) was investigated through the surface tension method. In addition, in the aqueous solution, the ¹H-NMR, as well as FT-IR studies of the studied pure and mixed system were also explored and deliberated thoroughly. In NaCl media, properties of pure/mixed interfacial surfaces enhanced as compared with the aqueous system, and consequently the synergism/attractive interaction among constituents (IMP and TX-100) grew, whereas in urea (U) media a reverse effect was detected. Surface excess concentration (Γ_max), composition of surfactant at mixed monolayer (X1σ), activity coefficient (f₁^σ (TX-100) and f₂^σ (IMP)), etc. were determined and discussed thoroughly. At mixed interfacial surfaces interaction, parameter (β^σ) reveals the attractive/synergism among the components. The Gibbs energy of adsorption (ΔGadso) value attained was negative throughout all employed media viewing the spontaneity of the adsorption process. The ¹H NMR spectroscopy was also employed to examine the molecular interaction of IMP and TX-100 in an aqueous system. FT-IR method as well illustrated the interaction amongst the component. The findings of the current study proposed that TX-100 surfactant could act as an efficient drug delivery vehicle for an antidepressant drug. Gels can be used as drug dosage forms due to recent improvements in the design of surfactant systems. Release mechanism of drugs from surfactant/polymer gels is dependent upon the microstructures of the gels and the state of the drugs within the system.

Improvements in the Oral Absorption and Anticancer Efficacy of an Oxaliplatin-Loaded Solid Formulation: Pharmacokinetic Properties in Rats and Nonhuman Primates and the Effects of Oral Metronomic Dosing on Colorectal Cancer

Objective

The anticancer efficacy of orally administered chemotherapeutics is often constrained by low intestinal membrane permeability and oral bioavailability. In this context, we designed a solid oral formulation of oxaliplatin (OP), a third-generation cisplatin analog, to improve oral bioavailability and investigate its application in metronomic chemotherapy.

Methods

An ion-pairing complex of OP with a permeation enhancer, N^α-deoxycholyl-l-lysyl-methylester (DLM), was successfully prepared and then mixed with dispersing agents (including poloxamer 188 and Labrasol) to form the solid, amorphous oral formulation OP/DLM (OP/DLM-SF; hereafter, ODSF).

Results

The optimized powder formulation was sized in the nanoscale range (133±1.47 nm). The effective permeability of OP increased by 12.4-fold after ionic complex formation with DLM and was further increased by 24.0-fold after incorporation into ODSF. ODSF exhibited respective increases of 128% and 1010% in apparent permeability across a Caco-2 monolayer, compared to OP/DLM and OP. Furthermore, inhibition of bile acid transporters by actinomycin D and caveola-mediated uptake by brefeldin in Caco-2 cell monolayers reduced the apparent permeability values of ODSF by 58.4% and 51.1%, respectively, suggesting predominant roles for bile acid transporters and caveola-mediated transport in intestinal absorption of ODSF. In addition, macropinocytosis and paracellular and transcellular passive transport significantly influenced the intestinal permeation of ODSF. The oral bioavailabilities of ODSF in rats and monkeys were 68.2% and 277% higher, respectively, than the oral bioavailability of free OP. In vivo analyses of anticancer efficacy in CT26 and HCT116 cell-bearing mice treated with ODSF demonstrated significant suppression of tumor growth, with respective maximal tumor volume reductions of 7.77-fold and 4.07-fold, compared to controls.

Conclusion

ODSF exhibits therapeutic potential, constituting an effective delivery system that increases oral bioavailability, with applications to metronomic chemotherapy.

Study of Structure of Water Droplets of Nonionic Polyoxyethylene (4) Lauryl Ether Reverse Micelles in the Presence of Sodium Cholate

The microenvironment of water droplets of nonionic polyoxyethylene (4) lauryl ether reverse micelles was investigated with infrared and ultraviolet-visible spectroscopy, also by viscosity and dynamic light scattering measurements in the presence of biological surfactant sodium cholate as additive. Influence of concentrations of polyoxyethylene (4) lauryl ether and sodium cholate on the microstructure of mixed reverse micelles was studied. Influence of sodium cholate as additive on the ratio of free, bound and trapped water fractions was studied via deconvolution of the O-H stretching vibrational absorption spectra in the region of 3 000–3 800 cm−1 into three subpeaks with a Monte Carlo method. Several characteristic parameters of reverse microemulsions were calculated on the basis of measurements of their kinematic viscosity. A different influence of concentration of sodium cholate on the binding constant and association degree of optical probes (o-nitroaniline and methyl orange respectively) to ethylene oxide groups of nonionic surfactant was observed. It was found that the bound water fraction, the binding constants and association degrees, the relative density of water pockets, etc. change their values passing through an extremum under the influence of sodium cholate.

Effect of Maltodextrin and Temperature on Micellar Behavior of Bile Salts in Aqueous Medium: Conductometric and Spectrofluorimetric Studies

Conductivity and fluorescence probe techniques have been employed to study the micellar behavior of bile salts i.e. sodium cholate (1–20 mmol⋅kg−1) and sodium deoxycholate (0.5–10.0 mmol⋅kg−1) in aqueous solutions of maltodextrin (0.0, 0.5, 1.1, and 1.6 mmol⋅kg−1) at different temperatures. The influence of maltodextrin on the micellization behavior of bile salts has been determined in terms of critical micelle concentration (CMC) values obtained from conductivity measurement. The variation in CMC values has been discussed by considering the alteration in the hydrophobic environment of maltodextrin-sodium cholate/sodium deoxycholate complex imparted by the carbohydrate molecules. In order to substantiate the CMC values determined from conductivity method, the fluorescence probe study of aqueous sodium cholate and sodium deoxycholate solutions in presence of fluorescent, pyrene has also been carried. The CMC values obtained from both techniques are in full agreement with each other. Moreover, application of charged pseudo-phase separation model has been made to discuss the thermodynamics of the system.

Human breast cancer decellularized scaffolds promote epithelial-to-mesenchymal transitions and stemness of breast cancer cells in vitro

Breast cancer, with unsatisfactory survival rates, is the leading cause of cancer-related death in women worldwide. Recent advances in the genetic basis of breast cancer have benefitted the development of gene-based medicines and therapies. Tissue engineering technologies, including tissue decellularizations and reconstructions, are potential therapeutic alternatives for cancer research and tissue regeneration. In our study, human breast cancer biopsies were decellularized by a detergent technique, with sodium lauryl ether sulfate (SLES) solution, for the first time. And the decellularization process was optimized to maximally maintain tissue microarchitectures and extracellular matrix (ECM) components with minimal DNA compounds preserved. Histology analysis and DNA quantification results confirmed the decellularization effect with maximal genetic compounds removal. Quantification, immunofluorescence, and histology analyses demonstrated better preservation of ECM components in 0.5% SLES-treated scaffolds. Scaffolds seeded with MCF-7 cells demonstrated the process of cell recellularization in vitro, with increased cell migration, proliferation, and epithelial-to-mesenchymal transition (EMT) process. When treated with 5-fluorouracil, the expressions of stem cell markers, including Oct4, Sox2, and CD49F, were maximally maintained in the recellularized scaffold with decreased apoptosis rates compared with monolayer cells. These results showed that the decellularized breast scaffold model with SLES treatments would help to simulate the pathogenesis of breast cancer in vitro. And we hope that this model could further accelerate the development of effective therapies for breast cancer and benefit drug screenings.

Pluronic®-bile salt mixed micelles

The present study was aimed to examine the interaction of two bile salts viz. sodium cholate (NaC) and sodium deoxycholate (NaDC) with three ethylene polyoxide-polypropylene polyoxide (PEO-PPO-PEO) triblock copolymers with similar PPO but varying PEO micelles with a focus on the effect of pH on mixed micelles. Mixed micelles of moderately hydrophobic Pluronic^® P123 were examined in the presence of two bile salts and compared with those from very hydrophobic L121 and very hydrophilic F127. Both the bile salts increase the cloud point (CP) of copolymer solution and decreased apparent micelle hydrodynamic diameter (D_h). SANS study revealed that P123 forms small spherical micelles showing a decrease in size on progressive addition of bile salts. The negatively charged mixed micelles contained fewer P123 molecules but progressively rich in bile salt. NaDC being more hydrophobic displays more pronounced effect than NaC. Interestingly, NaC shows micellar growth in acidic media which has been attributed to the formation of bile acids by protonation of carboxylate ion and subsequent solubilization. In contrast, NaDC showed phase separation at higher concentration. Nuclear Overhauser effect spectroscopy (NOESY) experiments provided information on interaction and location of bile salts in micelles. Results are discussed in terms of hydrophobicity of bile salts and Pluronics^® and the site of bile salt in polymer micelles. Proposed molecular interactions are useful to understand more about bile salts which play important role in physiological processes.

Solubilization and Interaction Studies of Bile Salts with Surfactants and Drugs: a Review

In this review, bile salt, bile salt-surfactant, and bile salt-drug interactions and their solubilization studies are mainly focused. Usefulness of bile salts in digestion, absorption, and excretion of various compounds and their rare properties in ordering the shape and size of the micelles owing to the presence of hydrophobic and hydrophilic faces are taken into consideration while compiling this review. Bile salts as potential bio-surfactants to solubilize drugs of interest are also highlighted. This review will give an insight into the selection of drugs in different applications as their properties get modified by interaction with bile salts, thus influencing their solution behavior which, in turn, modifies the phase-forming behavior, microemulsion, and clouding phenomenon, besides solubilization. Finally, their future perspectives are taken into consideration to assess their possible uses as bio-surfactants without side effects to human beings.

Microstructural micellar transition in bile salt–ionic liquid mixed systems in water: a DLS and SANS study

Bile salt assisted morphological changes of ionic liquid micelles.

Bile salt assisted morphological changes of cationic gemini surfactant (12-4-12) micelles

pH and concentration dependent growth of gemini surfactant (12-4-12) micelles in the presence of bile salts.

Non-alcoholic fatty liver disease, diet and gut microbiota

Non-alcoholic fatty liver disease (NAFLD) is a severe liver disease that is increasing in prevalence with the worldwide epidemic of obesity and its related insulin-resistance state. Evidence for the role of the gut microbiota in energy storage and the subsequent development of obesity and some of its related diseases is now well established. More recently, a new role of gut microbiota has emerged in NAFLD. The gut microbiota is involved in gut permeability, low-grade inflammation and immune balance, it modulates dietary choline metabolism, regulates bile acid metabolism and produces endogenous ethanol. All of these factors are molecular mechanisms by which the microbiota can induce NAFLD or its progression toward overt non-alcoholic steatohepatitis. Modification of the gut microbiota composition and/or its biochemical capacity by specific dietary or pharmacological interventions may advantageously affect host metabolism. Large-scale intervention trials, investigating the potential benefit of prebiotics and probiotics in improving cardiometabolic health in high-risk populations, are fervently awaited.