Browsing by Author "Madiehe, Abram Madimabe"

Now showing 1 - 7 of 7
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    The antimicrobial and anti-inflammatory effects of silver nanoparticles synthesised from cotyledon orbiculata aqueous extract
    (MDPI, 2021) Tyavambiza, Caroline; Elbagory, Abdulrahman Mohammed; Madiehe, Abram Madimabe
    Cotyledon orbiculata, commonly known as pig’s ear, is an important medicinal plant of South Africa. It is used in traditional medicine to treat many ailments, including skin eruptions, abscesses, inflammation, boils and acne. Many plants have been used to synthesize metallic nanoparticles, particularly silver nanoparticles (AgNPs). However, the synthesis of AgNPs from C. orbiculata has never been reported before. The aim of this study was to synthesize AgNPs using C. orbiculata and evaluate their antimicrobial and immunomodulatory properties. AgNPs were synthesized and characterized using Ultraviolet-Visible Spectroscopy (UV-Vis), Dynamic Light Scattering (DLS) and High-Resolution Transmission Electron Microscopy (HR-TEM).
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    The antioxidant and in vitro wound healing activity of cotyledon orbiculata aqueous extract and the synthesized biogenic silver nanoparticles
    (MDPI, 2022) Tyavambiza, Caroline; Meyer, Mervin; Madiehe, Abram Madimabe
    The synthesis of silver nanoparticles using biogenic methods, particularly plants, has led to the discovery of several effective nanoparticles. In many instances, plant-derived silver nanoparticles have been shown to have more activity than the plant extract which was used to synthesize the nanoparticles. Silver nanoparticles have been successfully synthesized using the medicinal plant, Cotyledon orbiculata. This is a shrub found in the Western Cape province of South Africa. It has a long history of use in traditional medicine in the treatment of wounds and skin infections. The C. orbiculata synthesized silver nanoparticles (Cotyledon-AgNPs) were reported to have good antimicrobial and anti-inflammatory activities; however, their wound-healing properties have not been determined. This study aimed to determine the wound healing activity of Cotyledon-AgNPs using the scratch assay. Gene expression studies were also done to determine the nanoparticles’ mechanism of action. The Cotyledon-AgNPs showed good antioxidant, growth-promoting and cell migration properties.
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    Computational insight of dexamethasone against potential targets of SARS-CoV-2
    (Taylor and Francis Group, 2022) Fadaka, Adewale Oluwaseun; Sibuyi, Nicole Remaliah Samantha; Madiehe, Abram Madimabe
    The health sector has been on the race to find a potent therapy for coronavirus disease (COVID)-19, a diseases caused by severe acute respiratory syndrome coronavirus (SARS-CoV)-2. Repurposed anti-viral drugs have played a huge role in combating the virus, and most recently, dexamethasone (Dex) have shown its therapeutic activity in severe cases of COVID-19 patients. The study sought to provide insights on the anti-COVID-19 mechanism of Dex at both atomic and molecular level against SARSCoV-2 targets. Computational methods were employed to predict the binding affinity of Dex to SARSCoV-2 using the Schrodinger suite (v2020-2). The target molecules and ligand (Dex) were retrieved from PDB and PubChem, respectively. The selected targets were SARS-CoV-2 main protease (Mpro), and host secreted molecules glucocorticoid receptor, and Interleukin-6 (IL-6). Critical analyses such as Protein and ligand preparation, molecular docking, molecular dynamic (MD) simulations, and absorption, distribution, metabolism, excretion (ADME), and toxicity analyses were performed using the targets and the ligand as inputs.
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    MicroRNA-based regulation of Aurora A kinase in breast cancer
    (Impact Journals, 2020) Sibuyi, Nicole Remaliah Samantha; Fadaka, Adewale Oluwaseun; Madiehe, Abram Madimabe
    The involvement of non-coding RNAs (ncRNAs) in cellular physiology and disease pathogenesis is becoming increasingly relevant in recent years specifically in cancer research. Breast cancer (BC) has become a health concern and accounts for most of the cancer-related incidences and mortalities reported amongst females. In spite of the presence of promising tools for BC therapy, the mortality rate of metastatic BC cases is still high. Therefore, the genomic exploration of the BC subtype and the use of ncRNAs for possible regulation is pivotal. The expression and prognostic values of AURKA gene were assessed by Oncomine, GEPIA, KM-plotter, and bc-GenExMiner v4.4, respectively. Associated proteins and functional enrichment were evaluated by Cytoscape and DAVID databases. Additionally, molecular docking approach was employed to investigate the regulatory role of hsa-miR-32-3p assisted argonaute (AGO) protein of AURKA gene in BC. AURKA gene was highly expressed in patients with BC relative to normal counterpart and significantly correlated with poor survival. The docking result suggested that AURKA could be regulated by hsa-miR-32-3p as confirmed by the reported binding energy and specific interactions. The study gives some insights into role of AURKA and its regulation by microRNAs through AGO protein. It also provides exciting opportunities for cancer therapeutic intervention. © 2020 Fadaka et al.
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    Nanotechnology-based delivery systems for antimicrobial peptides
    (MDPI, 2021) Adewale, Oluwaseun Fadaka; Sibuyi, Nicole Remaliah Samantha; Madiehe, Abram Madimabe; Meyer, Mervin
    Antimicrobial resistance (AMR) is a significant threat to global health. The conventional antibiotic pool has been depleted, forcing the investigation of novel and alternative antimicrobial strategies. Antimicrobial peptides (AMPs) have shown potential as alternative diagnostic and therapeutic agents in biomedical applications. To date, over 3000 AMPs have been identified, but only a fraction of these have been approved for clinical trials. Their clinical applications are limited to topical application due to their systemic toxicity, susceptibility to protease degradation, short half-life, and rapid renal clearance. To circumvent these challenges and improve AMP’s efficacy, different approaches such as peptide chemical modifications and the development of AMP delivery systems have been employed. Nanomaterials have been shown to improve the activity of antimicrobial drugs by providing support and synergistic effect against pathogenic microbes. This paper describes the role of nanotechnology in the targeted delivery of AMPs, and some of the nano-based delivery strategies for AMPs are discussed with a clear focus on metallic nanoparticle (MNP) formulations.
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    Peptide-functionalized quantum dots for potential applications in the imaging and treatment of obesity
    (DovePress, 2018) Thovhogi, Ntevheleni; Remaliah, Nicole; Sibuyi, Samantha; Onani, Martin Opiyo; Meyer, Mervin; Madiehe, Abram Madimabe
    BACKGROUND: Obesity is a worldwide epidemic affecting millions of people. The current pharmacological treatment of obesity remains limited and ineffective due to drugs’ undesirable side effects. Hence, there is a need for novel or improved strategies for long-term therapies that will help prevent the disease progression into other chronic diseases. Nanotechnology holds the future for the treatment of obesity because of its versatility, as shown by improved drug efficiency and safety in cancer clinical trials. Nano-based drug delivery systems could potentially do the same for obesity through targeted drug delivery. This study investigated the use of peptide-functionalized quantum dots (QDs) for the imaging of prohibitin (PHB)-expressing cells in vitro and in diet-induced obese rats, which could potentially be used as nanocarriers of antiobesity drugs. METHODS: Cadmium (Cd)-based QDs were functionalized with an adipose homing peptide (AHP) and injected intravenously into lean and obese Wistar rats. Biodistribution of the QDs was analyzed by an IVIS® Lumina XR imaging system and inductively coupled plasma optical emission spectroscopy (ICP-OES). For in vitro studies, PHB-expressing (Caco-2 and MCF-7) and non-PHB-expressing (KMST-6 and CHO) cells were exposed to either unfunctionalized QDs (QD625) or AHP-functionalized QDs (AHP-QD625) and analyzed by fluorescence microscopy. RESULTS: AHP-QD625 accumulated significantly in PHB-expressing cells in vitro when compared with non-PHB-expressing cells. In vivo data indicated that QD625 accumulated mainly in the reticuloendothelial system (RES) organs, while the AHP-QD625 accumulated mostly in the white adipose tissues (WATs). CONCLUSION: AHP-functionalized QDs were successfully and selectively delivered to the PHB-expressing cells in vitro (Caco-2 and MCF-7 cells) and in the WAT vasculature in vivo. This nanotechnology-based approach could potentially be used for dual targeted drug delivery and molecular imaging of adipose tissues in obese patients in real time.
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    Phytonanotherapeutic applications of plant extract-synthesized silver nanoparticles in wound healing—a prospective overview
    (Springer, 2024) Oselusi, Samson Olaitan; Sibuyi, Nicole Remaliah Samantha; Madiehe, Abram Madimabe
    Chronic wounds continue to pose severe threats to public health and the global economy. This is because the healing process is hindered by several factors, such as bacterial infections, comorbid conditions, age, and lifestyle. Medical wound therapy is currently based on long-term antibiotic use, and its activity has been limited by various factors, including treatment efficacy, toxicity, and increased risk of opportunistic infections. The advent of novel techniques such as nanotechnology can provide sustainable platforms for developing reliable, cost-effective, and innovative wound healing interventions. In this context, plant extract-synthesized silver nanoparticles (AgNPs) have become attractive to the clinical community because of their wide range of biological properties, such as antibacterial, anti-inflammatory, and wound healing effects. These AgNPs could be used in the development of better dressings for wounds.