Despite lacking the central apoptotic machinery, senescent or damaged RBCs can undergo an unusual apoptosis-like cell death, termed eryptosis. This premature death can be caused by, or a symptom of, a wide range of diseases. However, various adverse conditions, xenobiotics, and endogenous mediators have also been recognized as triggers and inhibitors of eryptosis. Eukaryotic RBCs are unique among their cell membrane distribution of phospholipids. The change in the RBC membrane composition of the outer leaflet occurs in a variety of diseases, including sickle cell disease, renal diseases, leukemia, Parkinson’s disease, and diabetes. Eryptotic erythrocytes exhibit various morphological alterations such as shrinkage, swelling, and increased granulation. Biochemical changes include cytosolic Ca²⁺ increase, oxidative stress, stimulation of caspases, metabolic exhaustion, and ceramide accumulation. Eryptosis is an effective mechanism for the elimination of dysfunctional erythrocytes due to senescence, infection, or injury to prevent hemolysis. Nevertheless, excessive eryptosis is associated with multiple pathologies, most notably anemia, abnormal microcirculation, and prothrombotic risk; all of which contribute to the pathogenesis of several diseases. In this review, we provide an overview of the molecular mechanisms, physiological and pathophysiological relevance of eryptosis, as well as the potential role of natural and synthetic compounds in modulating RBC survival and death.

Purpose: Redox homeostasis plays an important role in the osteogenic differentiation of human mesenchymal stem cells (hMSCs) for bone engineering. Oxidative stress (OS) is believed to induce osteoporosis by changing bone homeostasis. Selenium nanoparticles (SeNPs), an antioxidant with pleiotropic pharmacological activity, prevent bone loss. However, the molecular mechanism underlying the osteogenic activity during hMSC–SeNP interaction is unclear. Methods: This study assessed the effects of different concentrations (25, 50, 100, and 300 ng/mL) of SeNPs on the cell viability and differentiation ability of human embryonic stem cell-derived hMSCs. In addition, we analyzed OS markers and their effect on mitogen-activated protein kinase (MAPK) and Forkhead box O3 (FOXO3) during osteogenesis. Results: SeNPs increased the cell viability of hMSCs and induced their differentiation toward an osteogenic over an adipogenic lineage by enhancing osteogenic transcription and mineralization, while inhibiting Nile red staining and adipogenic gene expression. By preventing excessive reactive oxygen species accumulation, SeNPs increased antioxidant levels in hMSCs undergoing osteogenesis compared to untreated cells. In addition, SeNPs significantly upregulated the gene and protein expression of phosphorylated c-Jun N-terminal kinase (JNK) and FOXO3a, with no significant change in the expression levels of extracellular signal-related kinase (ERK) and p38 MAPK. Conclusion: The results approved that low concentrations of SeNPs might enhance the cell viability and osteogenic potential of hMSCs by moderating OS. Increased JNK and FOXO3a expression shows that SeNPs might enhance osteogenesis via activation of the JNK/FOXO3 pathway. In addition, SeNP co-supplementation might prevent bone loss by enhancing osteogenesis and, thus, can be an effective candidate for treating osteoporosis through cell-based therapy.

This study identified phytochemicals in Argemone mexicana (A. mexicana) extracts that are responsible for its medicinal properties, and the best solvent for their extraction. The extracts of the stem, leaves, flowers, and fruits of A. mexicana were prepared at low (corresponding to room temperature) and high temperatures (corresponding to the boiling points) in various solvents, viz., hexane, ethyl acetate, methanol, and H₂O. The UV-visible absorption spectra of various phytoconstituents in the isolated extracts were determined through spectrophotometry. Qualitative tests for the screening of phytoconstituents in the extracts were performed to identify various phytochemicals. We identified the presence of terpenoids, alkaloids, cardiac glycosides, and carbohydrates in the plant extracts. The antioxidant and anti-human immunodeficiency virus type 1 reverse transcriptase (anti-HIV-1RT) potential, as well as the antibacterial activity of various A. mexicana extracts were determined. These extracts showed strong antioxidant activities. The extracts exhibited antimicrobial activities against Salmonella typhi, Staphylococcus epidermis, Citrobacter, Neisseria gonorrhoeae, and Shigella flexineri. These extracts significantly inhibited HIV-1 reverse transcriptase activity. The aqueous leaf extract prepared at a temperature equivalent to the boiling point, i.e., 100 °C, was identified to be the most active against pathogenic bacteria and HIV-1 RT.

Thiol proteases are industrially significant proteins with catalytic efficiency. The effect of low, medium and high molecular-weight poly (ethylene glycol) (PEG- 400, 6000 and 20000) on the stability of thiol proteases (papain, bromelain and chymopapain) has been studied by activity measurements using synthetic substrate. Structural studies performed on papain by far UV circular dichroism spectroscopic measurements indicate that there is loss in secondary structure of the protein in presence of increasing concentration of PEGs. Intrinsic fluorescence measurements lead us to conclude that tryptophan residues of protein encounter non-polar microenvironment in presence of PEG solvent while acrylamide quenching shows greater accessibility of tryptophan residues of papain in presence of PEGs. Extrinsic fluorescence measurements lead us to conclude that PEGs bind to the hydrophobic sites on the protein and thus destabilize it. Thermal denaturation studies show that melting temperature of papain is decreased in presence of PEGs. Possible mechanism of destabilization is discussed next. The results imply that caution must be exercised in the use of PEGs with thiol proteases or hydrophobic proteins in general, for different industrial applications, even at room temperature.

Introduction: Clinical isolates of Pseudomonas aeruginosa (P. aeruginosa) are among the most recovered bacteria with phenotypic antimicrobial resistance. Bimetallic nanoparticles (BNPs) have received much attention for antimicrobial activity in the last decade. This research aimed to biosynthesize bimetallic copper oxide-selenium nanoparticles (CuO-Se BNPs) and to assess its bioactivity on various P. aeruginosa clinical isolates. Methodology: Based on the possible synergistic effects, CuO-Se BNPs were selected and biosynthesized using leaf extract of Lagenaria siceraria (L. siceraria) for the first time. The obtained BNPs were characterized using UV-vis spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and transmission and scanning electron microscopes. The capability of Cu-Se BNPs to cease the growth of P. aeruginosa isolates and to reduce their virulence characters was evaluated. Also, different cell lines were used to assess its cytotoxicity and anticancer activity. Results: The elemental composition of CuO and Se was revealed by the UV, XRD, and EDX data, indicating the synthesis of CuO-Se core shell BNPs with a size of 50 nm. In well diffusion assay, CuO-Se BNPs P. aeruginosa growth with 10– 21 mm inhibition zone diameter and 38– 95% inhibition. Also, the minimum inhibitory concentration and minimum bactericidal concentration were in a relatively wide range of 7.8– 250 μg/mL and 31.2– 500 μg/mL, respectively, with tolerance level range of 2– 16. Additionally, CuO-Se BNPs shown anti-pyocyanin activity of 4.35– 63.21% inhibition while the anti-proteolytic activity was in a range of 4.96– 12.59% and anti-pyoverdine effect was in a range of 0.24– 83.41%. The IC50 against Wi-38 normal cells was 267.2 μg/mL while the IC50 were 31.1 and 83.4 μg/mL against MCF-7 and Hep-G2, respectively, indicating promising anticancer activity. Conclusion: This research demonstrates the promising antibacterial, anti-virulence, and antitumor properties with safe low concentrations of CuO-Se NPs, synthesized via an eco-friendly green synthesis method without the use of toxic chemicals, offering a sustainable and cost-effective alternative.