Thiadiazine thione derivatives as anti-leishmanial agents: synthesis, biological evaluation, structure activity relationship, ADMET, molecular docking and molecular dynamics simulation studies.

During last decades, 3,5-disubstituted-tetrahydro-2H-thiadiazine-2-thione scaffold remains the center of interest due to their ease of preparation, diverse range substituents at N-3 and N-5 positions, and profound biological activities. In the current study, a series of 3,5-disubstituted-tetrahydro-2H-thiadiazine-2-thiones were synthesized in good to excellent yield, and the structure of the compounds were confirmed by various spectroscopic techniques such as FTIR, 1H-NMR, 13C-NMR and Mass spectrometry, and finally evaluated against Leishmania major. Whereas, all the evaluated compounds (1-33), demonstrate potential leishmanicidal activities with IC50 values in the range of (1.30- 149.98 uM). Among the evaluated compounds such as 3, 4, 6, and 10 exhibited excellent leishmanicidal activities with IC50 values of (2.17 µM), (2.39 µM), (2.00 µM), and (1.39 µM), respectively even better than the standard amphotericin B (IC50 = 0.50) and pentamidine (IC50 = 7.52). In order to investigate binding interaction of the most active compounds, molecular docking study was conducted with Leishmania major. Further molecular dynamic simulation study was also carried out to assess the stability and correct binding of the most active compound 10, within active site of the Leishamania major. Likewise, the physiochemical properties, drug likeness, and ADMET of the most active compounds were investigated, it was found that none of the compounds violate Lipiniski's rule of five, which show that this class of compounds had enough potential to be used as drug candidate in near future.Communicated by Ramaswamy H. Sarma.

Dihydropyrazole Derivatives Act as Potent α-Amylase Inhibitors and Free Radical Scavengers: Synthesis, Bioactivity Evaluation, Structure-Activity Relationship, ADMET, and Molecular Docking Studies.

Dihydropyrazole (1-22) derivatives were synthesized from already synthesized chalcones. The structures of all of the synthesized compounds were confirmed by elemental analysis and various spectroscopic techniques. Furthermore, the synthesized compounds were screened against α amylase as well as investigated for antioxidant activities. The synthesized compounds demonstrate good to excellent antioxidant activities with IC50 values ranging between 30.03 and 913.58 µM. Among the 22 evaluated compounds, 11 compounds exhibit excellent activity relative to the standard ascorbic acid IC50 = 287.30 µM. Interestingly, all of the evaluated compounds show good to excellent α amylase activity with IC50 values lying in the range between 0.5509 and 810.73 µM as compared to the standard acarbose IC50 = 73.12 µM. Among the investigated compounds, five compounds demonstrate better activity compared to the standard. In order to investigate the binding interactions of the evaluated compounds with amylase protein, molecular docking studies were conducted, which show an excellent docking score as compared to the standard. Furthermore, the physiochemical properties, drug likeness, and ADMET were investigated, and it was found that none of the compounds violate Lipiniski's rule of five, which shows that this class of compounds has enough potential to be used as a drug candidate in the near future.

Hyaluronic Acid-Based Nanocarriers for Anticancer Drug Delivery.

Hyaluronic acid (HA), a main component of the extracellular matrix, is widely utilized to deliver anticancer drugs due to its biocompatibility, biodegradability, non-toxicity, non-immunogenicity and numerous modification sites, such as carboxyl and hydroxyl groups. Moreover, HA serves as a natural ligand for tumor-targeted drug delivery systems, as it contains the endocytic HA receptor, CD44, which is overexpressed in many cancer cells. Therefore, HA-based nanocarriers have been developed to improve drug delivery efficiency and distinguish between healthy and cancerous tissues, resulting in reduced residual toxicity and off-target accumulation. This article comprehensively reviews the fabrication of anticancer drug nanocarriers based on HA in the context of prodrugs, organic carrier materials (micelles, liposomes, nanoparticles, microbubbles and hydrogels) and inorganic composite nanocarriers (gold nanoparticles, quantum dots, carbon nanotubes and silicon dioxide). Additionally, the progress achieved in the design and optimization of these nanocarriers and their effects on cancer therapy are discussed. Finally, the review provides a summary of the perspectives, the lessons learned so far and the outlook towards further developments in this field.

Study on galactosylated sodium alginate for enhancing HepG2 Cells adhesion and 3D printability.

Sodium alginate is a polyanionic natural polysaccharide polymer widely used in tissue engineering. However, the lack of binding domains for interaction with cells limits its application in regenerative medicine. This study designed a kind of galactosylated sodium alginate (G-SA) material with improved galactose grafting rate by EDC/NHS activation of carboxyl groups in MES buffer and subsequently cross-linking by Ca2+ aims to enhance the adherence behavior of HepG2 cells on alginate substrate. The synthesized G-SA was characterized by Fourier transform infrared spectra and nuclear magnetic resonance spectroscopy. G-SA exhibited good biocompatibility and significantly enhanced the adhesion behavior of HepG2 cells on its surface. Furthermore, we demonstrated that the effect of G-SA concentration in enhancing cell adhesion was diminished at higher than 2% w/v. Finally, the suitability of G-SA material is investigated for 3D printing, demonstrating that HepG2 cells could maintain high viability and excellent printability in the interior of the gel. In addition, cells could multiply and grow into cell spheroids with an average size of 200 µm in G-SA scaffolds. These results indicated that galactosylated sodium alginate material could be used as a 3D culture system that could be effective for engineering liver cancer models.

A manganese-phenolic network platform amplifying STING activation to potentiate MRI guided cancer chemo-/chemodynamic/immune therapy.

Low immune infiltration severely hinders the efficacy of cancer immunotherapy. Here, we developed a manganese-phenolic network platform (TMPD) to boost antitumor immunity via a stimulator of interferon gene (STING)-amplified activation cascade. TMPD is based on doxorubicin (DOX)-loaded PEG-PLGA nanoparticles and further coated with manganese (Mn2+)-tannic acid (TA) networks. Mechanistically, DOX-based chemotherapy and Mn2+-mediated chemodynamic therapy effectively promoted immunogenic cell death (ICD), characterized by abundant damage-associated molecular pattern (DAMP) exposure, which subsequently enhanced dendritic cells' (DCs) presentation of antigens. DOX-elicited DNA damage simultaneously caused cytoplasmic leakage of intracellular double-stranded DNA (dsDNA) as the STING signal initiator, while Mn2+ mediated significant upregulation in the expression of a STING pathway-related protein thereby amplifying the STING signal. Systemic intravenous administration of TMPD remarkably promoted DC maturation and CD8+ T cell infiltration, thus eliciting strong antitumor effects. Meanwhile, the released Mn2+ could serve as a contrast agent for tumor-specific T1-weighted magnetic resonance imaging (MRI). Moreover, TMPD combined with immune checkpoint blockade (ICB) immunotherapy significantly inhibited tumor growth and lung metastasis. Collectively, these findings indicate that TMPD has great potential in activating robust innate and adaptive immunity for MRI guided cancer chemo-/chemodynamic/immune therapy.

Three-Dimensional Bioprinting of Decellularized Extracellular Matrix-Based Bioinks for Tissue Engineering.

Three-dimensional (3D) bioprinting is one of the most promising additive manufacturing technologies for fabricating various biomimetic architectures of tissues and organs. In this context, the bioink, a critical element for biofabrication, is a mixture of biomaterials and living cells used in 3D printing to create cell-laden structures. Recently, decellularized extracellular matrix (dECM)-based bioinks derived from natural tissues have garnered enormous attention from researchers due to their unique and complex biochemical properties. This review initially presents the details of the natural ECM and its role in cell growth and metabolism. Further, we briefly emphasize the commonly used decellularization treatment procedures and subsequent evaluations for the quality control of the dECM. In addition, we summarize some of the common bioink preparation strategies, the 3D bioprinting approaches, and the applicability of 3D-printed dECM bioinks to tissue engineering. Finally, we present some of the challenges in this field and the prospects for future development.

Role of supercritical carbon dioxide (scCO2) in fabrication of inorganic-based materials: a green and unique route.

In recent times, the supercritical carbon dioxide (scCO2) process has attracted increasing attention in fabricating diverse materials due to the attractive features of environmentally benign nature and economically promising character. Owing to these unique characteristics and high-penetrability, as well as diffusivity conditions of scCO2, this high-pressure technology, with mild operation conditions, cost-effective, and non-toxic, among others, is often applied to fabricate various organic and inorganic-based materials, resulting in the unique crystal architectures (amorphous, crystalline, and heterojunction), tunable architectures (nanoparticles, nanosheets, and aerogels) for diverse applications. In this review, we give an emphasis on the fabrication of various inorganic-based materials, highlighting the recent research on the driving factors for improving the quality of fabrication in scCO2, procedures for production and dispersion in scCO2, as well as common indicators utilized to assess quality and processing ability of materials. Next, we highlight the effects of specific properties of scCO2 towards synthesizing the highly functional inorganic-based nanomaterials. Finally, we summarize this compilation with interesting perspectives, aiming to arouse a more comprehensive utilization of scCO2 to broaden the horizon in exploring the green/eco-friendly processing of such versatile inorganic-based materials. Together, we firmly believe that this compilation endeavors to disclose the latent capability and universal prevalence of scCO2 in the synthesis and processing of inorganic-based materials.

Fabrication of Supercritical Antisolvent (SAS) Process-Assisted Fisetin-Encapsulated Poly (Vinyl Pyrrolidone) (PVP) Nanocomposites for Improved Anticancer Therapy.

Due to its hydrophobicity, fisetin (FIS) often suffers from several limitations in terms of its applicability during the fabrication of pharmaceutical formulations. To overcome this intrinsic limitation of hydrophobicity, we demonstrate here the generation of poly (vinyl pyrrolidone) (PVP)-encapsulated FIS nanoparticles (FIS-PVP NPs) utilizing a supercritical antisolvent (SAS) method to enhance its aqueous solubility and substantial therapeutic effects. In this context, the effects of various processing and formulation parameters, including the solvent/antisolvent ratio, drug/polymer (FIS/PVP) mass ratio, and solution flow rate, on the eventual particle size as well as on distribution were investigated using a 23 factorial experimental design. Notably, the FIS/PVP mass ratio significantly affected the morphological attributes of the resultant particles. Initially, the designed constructs were characterized systematically using various techniques (e.g., chemical functionalities were examined with Fourier-transform infrared (FTIR) spectroscopy, and physical states were examined with X-ray diffraction analysis (XRD) and differential scanning calorimetry (DSC) techniques). In addition, drug release as well as cytotoxicity evaluations in vitro indicated that the nanosized polymer-coated particles showed augmented performance efficiency compared to the free drug, which was attributable to the improvement in the dissolution rate of the FIS-PVP NPs due to their small size, facilitating a higher surface area over the raw form of FIS. Our findings show that the designed SAS process-assisted nanoconstructs with augmented bioavailability, have great potential for applications in pharmaceutics.

Supercritical Fluid-Assisted Fabrication of Manganese (III) Oxide Hollow Nanozymes Mediated by Polymer Nanoreactors for Efficient Glucose Sensing Characteristics.

Despite their inherent efficacy in significantly accelerating the rate of chemical reactions in biological processes, the applicability of natural enzymes is often hindered because of their intrinsic limitations such as high sensitivity, poor operational stability, and relatively high cost for purification as well as preparation. Thus, the fabrication of catalytically active nanomaterials as artificial enzymes (nanozymes) has become a newly burgeoning area of research in bionic chemistry, aiming in designing functional nanomaterials that mimic various inherent properties of natural enzymes. To address these issues, we present the supercritical fluid (SCF)-assisted fabrication of discrete, monodisperse, and uniform-sized manganese (III) oxide (Mn2O3)-based hollow containers as high-efficiency nanozymes for glucose sensing characteristics. Initially, the core-shell nanoreactors based on polyvinylpyrrolidone (PVP)-encapsulated manganese (III) acetylacetonate (Mn(acac)3) as precursors are fabricated using the SCF technology and subsequent calcination resulted in the Mn2O3 hollow nanoparticles (MHNs). This eco-friendly approach has resulted in the PVP-coated Mn(acac)3 nanoreactors with an average diameter of 220 nm and subsequent calcined hollow products are about one-fifth to that of the precursor. Such MHNs conveniently catalyzed 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H2O2) as a prominent peroxidase mimic, resulting in the oxidation products (TMB*+) at a specific absorption (UV-vis) maxima of 652 nm. Following typical Michaelis-Menten theory, this approach is further utilized to develop visual nonenzymatic sensing of glucose in a linear range of 0.1-1 mM at a detection limit of 2.31 µM. Collectively, this reliable as well as a cost-effective system with high precision potentially allows rapid detection of analytes, providing a convenient way for its utilization in diverse fields.

Targeted Magnetic Resonance Imaging and Modulation of Hypoxia with Multifunctional Hyaluronic Acid-MnO2 Nanoparticles in Glioma.

Manganese dioxide (MnO2 )-based nanoparticles are a promising tumor microenvironment-responsive nanotheranostic carrier for targeted magnetic resonance imaging (MRI) and for alleviating tumor hypoxia. However, the complexity and potential toxicity of the present common synthesis methods limit their clinical application. Herein, multifunctional hyaluronic acid-MnO2 nanoparticles (HA-MnO2 NPs) are synthesized in a simple way by directly mixing sodium permanganate with HA aqueous solutions, which serve as both a reducing agent and a surface-coating material. The obtained HA-MnO2 NPs show an improved water-dispersibility, fine colloidal stability, low toxicity, and responsiveness to the tumor microenvironment (high H2 O2 and high glutathione, low pH). After intravenous injection, HA-MnO2 NPs exhibit a high imaging sensitivity for detecting rat intracranial glioma with MRI for a prolonged period of up to 3 d. These nanoparticles also effectively alleviate the tumor hypoxia in a rat model of intracranial glioma. The downregulation of VEGF and HIF-1α expression in intracranial glioma validates the sustained attenuation effect of HA-MnO2 NPs on tumor hypoxia. These results show that HA-MnO2 NPs can be used for sensitive, targeted MRI detection of gliomas and simultaneous attenuation of tumor hypoxia.