Showing papers by "Rama Shanker Verma published in 2022"

Antioxidant α-Mangostin Coated Woven Polycaprolactone Nanofibrous Yarn Scaffold for Cardiac Tissue Repair

Abstract: Electrospun nanofibrous scaffolds are one of the most extensively used proven candidates for scaffold-based tissue engineering applications due to their excellent nanoscale architecture and tailorable nature. Despite the advantages of electrospun scaffolds, drawbacks such as low mechanical strength and densely packed nanofibers lead to decreased cell infiltration, preventing diffusion of nutrients and gases. To overcome these shortfalls, nanofiber yarns formed by directly twisting thousands of electrospun nanofibers are considered as building blocks for scaffold fabrication with an appropriate mechanical strength and porosity to enhance cell infiltration. The study illustrates a unique and feasible method to synthesize electrospun nanofiber yarns by using modified collector electrospinning and the yarns were weaved to form a fabric-like scaffold. α-Mangostin, a plant-based bioactive compound with cardioprotective, anti-inflammatory and antioxidant properties was incorporated into the woven scaffold to evaluate its efficacy as a cardiac patch. Results showed that modification in the scaffold architecture from spun nanofibers to nanofiber yarns led to increase in hydrophilicityleading to enhanced protein adsorption, degradation, cell proliferation, spreading, and infiltration. Here, we report the fabrication of a 3D woven polymer nanofibrous yarn scaffold coated with α-mangostin for cardiac patch applications. Results from the study showed that the scaffold favored stem cell proliferation and supported the functionality of cardiac cells. These fabricated 3D woven scaffolds showed improved angiogenesis and increased tissue compatibility in vivo, showing prospects for the use of a woven scaffold as an ideal template for cardiac tissue engineering applications.

Designing of Smart Nanogels based on Tragacanth Gum for Cisplatin Delivery

Abstract: The present work deals with the development of smart nanogels with a coating of the lipid layer, which synergized the triggered delivery of the anticancer drug, cisplatin (CP). In the first step, the chemical initiation method carried out the grafting of polyitaconic acid (PIA) on Tragacanth gum (TG). Subsequently, this grafted TG matrix was used for the synthesis of nanoparticles. Nanoemulsion process was followed to prepare CP loaded grafted TG-Lecithin (nGTG-LC) nanogels using dioctyl sulfosuccinate (AOT), as the surfactant. These nanoparticles were characterized for size, morphology, elemental analysis, and crystallinity. The TEM images of GTG-LC nanogels with varying concentrations of CP demonstrated the irregular polygonal shape of the nanoparticles which is strongly influenced by the CP concentration. The smart nanogels exhibit a unique structure, nano-within-nano, the structure where nano-sized CP is encapsulated within the TG-LC nanogel. Grafted nanogels have a high carboxyl functionality and acquire pH-sensitive behavior leading to pH-responsive drug release behavior. These nanogel show required biocompatibility and offer interesting material for nanomedicines in chemotherapy. This article is protected by copyright. All rights reserved.

Fluid shear stress in a logarithmic microfluidic device enhances cancer cell stemness marker expression.

Abstract: Fluid shear stress (FSS) is crucial in cancer cell survival and tumor development. Noteworthily, cancer cells are exposed to several degrees of FSS in the tumor microenvironment and during metastasis. Consequently, the stemness marker expression in cancer cells changes with the FSS signal, although it is unclear how it varies with different magnitudes and during metastasis. The current work explores the stemness and drug resistance characteristics of the cervical cancer cell line HeLa in a microfluidic device with a wide range of physiological FSS. Hence, the microfluidic device was designed to achieve a logarithmic flow distribution in four culture chambers, realizing four orders of biological shear stress on a single chip. The cell cycle analysis demonstrated altered cell proliferation and mitotic arrest after FSS treatment. In addition, EdU staining revealed increased cell proliferation with medium to low FSS, whereas high shear had a suppressing effect. FSS increased competence to withstand higher intracellular ROS and mitochondrial membrane potential in HeLa. Furthermore, stemness-related gene (Sox2, N-cadherin) and cell surface marker (CD44, CD33, CD117) expressions were enhanced by FSS mechanotransduction in a magnitude-dependent manner. In summary, these stemness-like properties were concurrent with the drug resistance capability of HeLa towards doxorubicin. Overall, our microfluidic device elucidates cancer cell survival and drug resistance mechanisms during metastasis and in cancer relapse patients.

Multiple Cues In Acellular Amniotic Membrane Incorporated Embelin For Tissue Engineering

Abstract: Human Amniotic Membranes (hAM) are an indispensable source as the components of the tissue engineering triad: scaffolds, cells, and bioactive molecules. Native collagen mimetic hAM is advantageous for biocompatibility, low cost, and availability as a scaffolding biomaterial for regenerative medicine. Recently, hAM has been recast as a potential source of composite biomaterial by various preparation techniques that aim at retaining growth factors and secretome. The exploration of hAM scaffolds its topography, its constituting array of bioactive molecules, and modality of application remain nascent. The wound healing cascade requisites elimination of over accumulated and deleterious Reactive Oxygen Species (ROS) to accelerate tissue repair and regenerative processes. The study reports decellularized, dehydrated Amniotic Membrane (dAM) incorporated with embelin, a natural benzoquinone compound synthesized from Embelia ribes for neutralizing free radicals, while simultaneously accelerates wound healing. hAM processed from the placenta has been characterized for integrity by histology, bio-degradability, thermogravimetric analysis (TGA), and cytokines analysis determined the presence of growth factors vital for tissue regeneration. The spectroscopic analysis confirmed the synthesized embelin and demonstrated burst release (>80%) from the embelin incorporated dAM supported by mathematical modelling. Surface topography and roughness of embelin incorporated AM were examined by scanning electron microscopy and atomic force microscopy respectively. In addition to anti-oxidant activity, the presence of embelin has significantly improved the initial fibroblast cell adhesion and proliferation compared to plain dAM and TCPS. In brief, the collagen mimetic intact dAM retains growth factors bioactivity and the anti-oxidant embelin synergistically influences the fibroblast cells thereby aid rapid wound healing and tissue regeneration.