Anion exchanger1 (AE1/SLC4A1) function is impaired in red blood cells from prediabetic subjects: Potential benefits of finger lime (Citrus australasica, Faustrime cultivar) juice extract.

Prediabetes is a risk state that defines a high chance of developing diabetes and cardiovascular disease. Oxidative stress mediated by hyperglycemia-induced production of reactive species could play a crucial role in this context. In the present study, we investigated whether the anion exchange capability mediated by AE1 (SLC4A1), which is sensitive to oxidative stress, was altered in human red blood cells (RBCs) obtained from prediabetic volunteers. In addition, we assessed the precise composition of bioactive compounds and the potential benefits of finger lime juice extract (Citrus australasica, Faustrime cultivar) in counteracting oxidative stress-related functional alterations. Human RBCs from normal and prediabetic volunteers were incubated with 50 µg/mL juice extract for 2 h at 25°C. Juice extract restored alterations of the anion exchange capability mediated by AE1 and prevented the structural rearrangements of AE1 and α/ß-spectrin in prediabetic RBCs. AE1 functional and structural alterations were not associated with an increase in lipid peroxidation or protein oxidation at the level of the plasma membrane. An increased production of intracellular ROS, which provoked the oxidation of hemoglobin to methemoglobin, both reverted by juice extract, was instead observed. Importantly, juice extract also induced a reduction in glycated hemoglobin levels in prediabetic RBCs. Finally, juice extract blunted the overactivation of the endogenous antioxidant enzymes catalase and superoxide dismutase and prevented glutathione depletion in prediabetic RBCs. These findings contribute to clarifying cellular and molecular mechanisms related to oxidative stress and glycation events that may influence RBC and systemic homeostasis in prediabetes, identify AE1 as a sensitive biomarker of RBC structural and function alterations in prediabetes and propose finger lime juice extract as a natural antioxidant for the treatment and/or prevention of the complications associated with the prediabetic condition.

Poly-basic peptides and polymers as new drug candidates against Plasmodium falciparum.

BACKGROUND: Plasmodium falciparum, the malaria-causing parasite, is a leading cause of infection-induced deaths worldwide. The preferred treatment approach is artemisinin-based combination therapy, which couples fast-acting artemisinin derivatives with longer-acting drugs, such as lumefantrine, mefloquine, and amodiaquine. However, the urgency for new treatments has risen due to the parasite's growing resistance to existing therapies. In this study, a common characteristic of the P. falciparum proteome-stretches of poly-lysine residues, such as those found in proteins related to adhesion and pathogenicity-is investigated for its potential to treat infected erythrocytes. METHODS: This study utilizes in vitro culturing of intra-erythrocytic P. falciparum to assess the ability of poly-lysine peptides to inhibit the parasite's growth, measured via flow cytometry of acridine orange-stained infected erythrocytes. The inhibitory effect of many poly-lysine lengths and modifications were tested this way. Affinity pull-downs and mass spectrometry were performed to identify the proteins interacting with these poly-lysines. RESULTS: A single dose of these poly-basic peptides can successfully diminish parasitemia in human erythrocytes in vitro with minimal toxicity. The effectiveness of the treatment correlates with the length of the poly-lysine peptide, with 30 lysine peptides supporting the eradication of erythrocytic parasites within 72 h. PEG-ylation of the poly-lysine peptides or utilizing poly-lysine dendrimers and polymers retains or increases parasite clearance efficiency and bolsters the stability of these potential new therapeutics. Lastly, affinity pull-downs and mass-spectrometry identify P. falciparum's outer membrane proteins as likely targets for polybasic peptide medications. CONCLUSION: Since poly-lysine dendrimers are already FDA-approved for drug delivery and this study displays their potency against intraerythrocytic P. falciparum, their adaptation as anti-malarial drugs presents a promising new therapeutic strategy for malaria.

Dual protection of aqueous garlic extract biomolecules against hemolysis and its oxidation products in preventing inflammation.

Garlic (Allium sativum) is recognized as functional food, rich in bioactive compounds that can combat diseases associated with oxidative stress. This study aims to investigate the protective potential of aqueous garlic extract against hemolysis and oxidation. Despite being caused by membrane fragility, hemolysis can lead to inflammation through the oxidation of its products, and in some cases, even exacerbate it in certain pathological contexts. Supplementation with antioxidant molecules can improves oxidative status, in this study, we selected garlic, an excellent functional food, and targeted its effects using aqueous extract and pure molecules. The aqueous garlic extract was prepared under safe conditions and subjected to toxicity on human neutrophils and red blood cells before experimentation. The results indicate that aqueous garlic extract significantly reduces hemolysis with a maximum protection of  98. 74 ± 1. 08 % at a concentration of 5µg/ml. Additionally, experiments were conducted with pure compounds found in garlic such as quercetin, gallic acid, and caffeic acid. The outcomes show that quercetin reduces hemolysis of RBC with a maximum protection of  88. 8 ± 2. 89 % at 20 µM followed by caffeic acid and gallic acid. The action mechanism of the extract was tested on human neutrophil cells, the extract significantly reduced luminol-amplified chemiluminescence of PMA-stimulated neutrophils up to 50 % at 10 µg/ml in addition to its ability to directly scavenge hydrogen peroxide. Our results suggest that aqueous garlic extract exerts promising anti-inflammatory activity in vitro. Through its dual protection against hemolysis and Ros production, garlic may indirectly prevent inflammation reducing the oxidation of hemolysis products. These abilities make garlic aqueous extract promising candidate for improving cardiovascular health, reducing oxidative stress and modulating immunity.

Genotoxicity and cytotoxicity assessment of 'forever chemicals' in zebrafish (Danio rerio).

Per- and polyfluoroalkyl substances (PFAS) comprise many chemicals with strong carbon-carbon and carbon-fluorine bonds and have extensive industrial applications in manufacturing several consumer products. The solid covalent bonding makes them more persistent in the environment and stays away from all types of degradation, naming them 'forever chemicals.' Zebrafish (Danio rerio) was used to evaluate the genotoxic and cytotoxic effects of legacy PFAS, Perfluorooctane sulfonate (PFOS), and its alternatives, such as Perfluoro-2-methyl-3-oxahexanoic acid ammonium (GenX) and 7H-Perfluoro-3,6-dioxa-4-methyl-octane-1-sulfonic acid (Nafion by-product 2 [NBP2]) upon single and combined exposure at an environmental concentration of 10 µg/L for 48-h. Erythrocyte micronucleus cytome assay (EMNCA) revealed an increased frequency of micronuclei (MN) in fish erythrocytes with a significant increase in NBP2-treated fish. The order of genotoxicity noticed was NBP2 > PFOS > Mixture > GenX in D. rerio. Fish exposed to PFOS and its alternatives in single and combined experiments did not cause any significant difference in nuclear abnormalities. However, PFOS and combined exposure positively inhibit cytokinesis, resulting in an 8.16 and 7.44-fold-change increase of binucleated cells. Besides, statistically, increased levels of reactive oxygen species (ROS) and malondialdehyde (MDA) content indicate oxidative stress in D. rerio. In addition, 'forever chemicals' resulted in cytotoxicity, as evident through changes in nucleus width to the erythrocyte length in NBP2 and mixture exposure groups. The findings revealed that PFAS alternative NBP2 is more toxic than PFOS in inducing DNA damage and cytotoxicity. In addition, all three tested 'forever chemicals' induced ROS and lipid peroxidation after individual and combined exposure. The present work is the first to concern the genotoxicity and cytotoxicity of 'forever chemicals' in the aquatic vertebrate D. rerio.

Protective Effect of Polyphenolic Extracts from Hippophae rhamnoides L. and Reynoutria japonica Houtt. on Erythrocyte Membrane.

Sea buckthorn and Japanese knotweed are known in many traditional medicine systems to be a great source of bioactive substances. This research aims to compare the bioactivity and protective effects of the phenolic extracts of leaves from sea buckthorn and roots and leaves from the Japanese knotweed on erythrocytes. The polyphenol composition of the extract was analyzed using UPLC-PDA-ESI-MS/MS. The extracts' toxicity and impact on the erythrocytes' osmotic fragility were measured spectrophotometrically. The antioxidant activity was determined based on the inhibition of oxidation of erythrocytes and their membrane induced by 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH),measured spectrophotometrically and using fluorimetry. To find the possible mechanism of the extracts' action, extract-modified cells were observed under a microscope, and the potential localization of the extract's phytochemical composition was checked using fluorescent probes. The results showed that the used extracts are not toxic to erythrocytes, increase their osmotic resistance, and successfully protect them against free radicals. Extract components localize on the outer part of the membrane, where they can scavenge the free radicals from the environment. Altogether, the presented extracts can greatly protect living organisms against free radicals and can be used to support the treatment of diseases caused by excess free radicals.

Red blood cells based nanotheranostics: A smart biomimetic approach for fighting against cancer.

The technique of engineering drug delivery vehicles continues to develop, which bring enhancements in working more efficiently and minimizing side effects to make it more effective and safer. The intense capability of therapeutic agents to remain undamaged in a harsh extracellular environment is helpful to the success of drug development efforts. With this in mind, alterations of biopharmaceuticals with enhanced stability and decreased immunogenicity have been an increasingly active focus of such efforts. Red blood cells (RBCs), also known as erythrocytes have undergone extensive scrutiny as potential vehicles for drug delivery due to their remarkable attributes over the years of research. These include intrinsic biocompatibility, minimal immunogenicity, flexibility, and prolonged systemic circulation. Throughout the course of investigation, a diverse array of drug delivery platforms based on RBCs has emerged. These encompass genetically engineered RBCs, non-genetically modified RBCs, and RBC membrane-coated nanoparticles, each devised to cater to a range of biomedical objectives. Given their prevalence in the circulatory system, RBCs have gained significant attention for their potential to serve as biomimetic coatings for artificial nanocarriers. By virtue of their surface emulation capabilities and customizable core materials, nanocarriers mimicking these RBCs, hold considerable promise across a spectrum of applications, spanning drug delivery, imaging, phototherapy, immunomodulation, sensing, and detection. These multifaceted functionalities underscore the considerable therapeutic and diagnostic potential across various diseases. Our proposed review provides the synthesis of recent strides in the theranostic utilization of erythrocytes in the context of cancer. It also delves into the principal challenges and prospects intrinsic to this realm of research. The focal point of this review pertains to accentuating the significance of erythrocyte-based theranostic systems in combating cancer. Furthermore, it precisely records the latest and the most specific methodologies for tailoring the attributes of these biomimetic nanoscale formulations, attenuating various discoveries for the treatment and management of cancer.

Guanidinium Chloride-Induced Haemolysis Assay to Measure New Permeation Pathway Functionality in Rodent Malaria Plasmodium berghei.

Parasite-derived new permeation pathways (NPPs) expressed at the red blood cell (RBC) membrane enable Plasmodium parasites to take up nutrients from the plasma to facilitate their survival. Thus, NPPs represent a potential novel therapeutic target for malaria. The putative channel component of the NPP in the human malaria parasite P. falciparum is encoded by mutually exclusively expressed clag3.1/3.2 genes. Complicating the study of the essentiality of these genes to the NPP is the addition of three clag paralogs whose contribution to the P. falciparum channel is uncertain. Rodent malaria P. berghei contains only two clag genes, and thus studies of P. berghei clag genes could significantly aid in dissecting their overall contribution to NPP activity. Previous methods for determining NPP activity in a rodent model have utilised flux-based assays of radioisotope-labelled substrates or patch clamping. This study aimed to ratify a streamlined haemolysis assay capable of assessing the functionality of P. berghei NPPs. Several isotonic lysis solutions were tested for their ability to preferentially lyse infected RBCs (iRBCs), leaving uninfected RBCs (uRBCs) intact. The osmotic lysis assay was optimised and validated in the presence of NPP inhibitors to demonstrate the uptake of the lysis solution via the NPPs. Guanidinium chloride proved to be the most efficient reagent to use in an osmotic lysis assay to establish NPP functionality. Furthermore, following treatment with guanidinium chloride, ring-stage parasites could develop into trophozoites and schizonts, potentially enabling use of guanidinium chloride for parasite synchronisation. This haemolysis assay will be useful for further investigation of NPPs in P. berghei and could assist in validating its protein constituents.

The Composition of Triterpene Glycosides in the Sea Cucumber Psolus peronii: Anticancer Activity of the Glycosides against Three Human Breast Cancer Cell Lines and Quantitative Structure-Activity Relationships (QSAR).

Eight sulfated triterpene glycosides, peronioside A (1) and psolusosides A (2), B (3), G (4), I (5), L (6), N (7) and P (8), were isolated from the sea cucumber Psolus peronii. Peronioside A (1) is a new glycoside, while compounds 2-8 were found previously in Psolus fabricii, indicating the phylogenetic and systematic closeness of these species of sea cucumbers. The activity of 1-8 against human erythrocytes and their cytotoxicity against the breast cancer cell lines MCF-7, T-47D and triple-negative MDA-MB-231 were tested. The most active against cancer cell compounds, psolusosides A (2) and L (6), which were not cytotoxic to the non-transformed cells of the mammary gland, were chosen to study the inhibition of the migration, formation and growth of colonies of the cancer cell lines. Glycoside 2 effectively inhibited the growth of colonies and the migration of the MDA-MB-231 cell line. Compound 6 blocked the growth of colonies of T-47D cells and showed a pronounced antimigration effect on MDA-MB-231 cells. The quantitative structure-activity relationships (QSAR) indicated the strong impact on the activity of the form and size of the molecules, which is connected to the length and architecture of the carbohydrate chain, the distribution of charge on the molecules' surface and various aspects of hydrogen bond formation, depending on the quantity and positions of the sulfate groups. The QSAR calculations were in good accordance with the observed SAR tendencies.

Acrolein Induces Changes in Cell Membrane and Cytosol Proteins of Erythrocytes.

High concentrations of acrolein (2-propenal) are found in polluted air and cigarette smoke, and may also be generated endogenously. Acrolein is also associated with the induction and progression of many diseases. The high reactivity of acrolein towards the thiol and amino groups of amino acids may cause damage to cell proteins. Acrolein may be responsible for the induction of oxidative stress in cells. We hypothesized that acrolein may contribute to the protein damage in erythrocytes, leading to the disruption of the structure of cell membranes. The lipid membrane fluidity, membrane cytoskeleton, and osmotic fragility were measured for erythrocytes incubated with acrolein for 24 h. The levels of thiol, amino, and carbonyl groups were determined in cell membrane and cytosol proteins. The level of non-enzymatic antioxidant potential (NEAC) and TBARS was also measured. The obtained research results showed that the exposure of erythrocytes to acrolein causes changes in the cell membrane and cytosol proteins. Acrolein stiffens the cell membrane of erythrocytes and increases their osmotic sensitivity. Moreover, it has been shown that erythrocytes treated with acrolein significantly reduce the non-enzymatic antioxidant potential of the cytosol compared to the control.

Factors influencing the efficacy of recombinant tissue plasminogen activator: Implications for ischemic stroke treatment.

Intravenous thrombolysis with a recombinant tissue plasminogen activator (rt-PA) is the first-line treatment of acute ischemic stroke. However, successful recanalization is relatively low and the underlying processes are not completely understood. The goal was to provide insights into clinically important factors potentially limiting rt-PA efficacy such as clot size, rt-PA concentration, clot age and also rt-PA in combination with heparin anticoagulant. We established a static in vitro thrombolytic model based on red blood cell (RBC) dominant clots prepared using spontaneous clotting from the blood of healthy donors. Thrombolysis was determined by clot mass loss and by RBC release. The rt-PA became increasingly less efficient for clots larger than 50 µl at a clinically relevant concentration of 1.3 mg/l. A tenfold decrease or increase in concentration induced only a 2-fold decrease or increase in clot degradation. Clot age did not affect rt-PA-induced thrombolysis but 2-hours-old clots were degraded more readily due to higher activity of spontaneous thrombolysis, as compared to 5-hours-old clots. Finally, heparin (50 and 100 IU/ml) did not influence the rt-PA-induced thrombolysis. Our study provided in vitro evidence for a clot size threshold: clots larger than 50 µl are hard to degrade by rt-PA. Increasing rt-PA concentration provided limited thrombolytic efficacy improvement, whereas heparin addition had no effect. However, the higher susceptibility of younger clots to thrombolysis may prompt a shortened time from the onset of stroke to rt-PA treatment.

Red Blood Cell-Hitchhiking Delivery of Simvastatin to Relieve Acute Respiratory Distress Syndrome.

Purpose: The purpose of this study is to address the high mortality and poor prognosis associated with Acute Respiratory Distress Syndrome (ARDS), conditions characterized by acute and progressive respiratory failure. The primary goal was to prolong drug circulation time, increase drug accumulation in the lungs, and minimize drug-related side effects. Methods: Simvastatin (SIM) was used as the model drug in this study. Employing a red blood cell surface-loaded nanoparticle drug delivery technique, pH-responsive cationic nanoparticles loaded with SIM were non-covalently adsorbed onto the surface of red blood cells (RBC), creating a novel drug delivery system (RBC@SIM-PEI-PPNPs). Results: The RBC@SIM-PEI-PPNPs delivery system effectively extended the drug's circulation time, providing an extended therapeutic window. Additionally, this method substantially improved the targeted accumulation of SIM in lung tissues, thereby enhancing the drug's efficacy in treating ARDS and impeding its progression to ARDS. Crucially, the system showed a reduced risk of adverse drug reactions. Conclusion: RBC@SIM-PEI-PPNPs demonstrates promise in ARDS and ARDS treatment. This innovative approach successfully overcomes the limitations associated with SIM's poor solubility and low bioavailability, resulting in improved therapeutic outcomes and fewer drug-related side effects. This research holds significant clinical implications and highlights its potential for broader application in drug delivery and lung disease treatment.

Anti-Leishmania effect of icetexanes from Salvia procurrens.

BACKGROUND AND PURPOSE: Leishmaniasis is a globally prevalent vector-borne disease caused by parasites of the genus Leishmania. The available chemotherapeutic drugs present problems related to efficacy, emergence of parasite resistance, toxicity and high cost, justifying the search for new drugs. Several classes of compounds have demonstrated activity against Leishmania, including icetexane-type diterpenes, previously isolated from Salvia and other Lamiaceae genera. Thus, in this study, compounds of Salvia procurrens were investigated for their leishmanicidal and immunomodulatory activities. METHODS: The exudate of S. procurrens was obtained by rapidly dipping the aerial parts in dichloromethane. The compounds were isolated by column and centrifugal planar chromatography over silica gel. The effects on L. amazonensis growth, survival, membrane integrity, reactive oxygen species (ROS) generation, mitochondrial membrane potential and cytotoxicity of the compounds towards human erythrocytes, peripheral blood mononuclear cells and macrophages were evaluated. The effects on intracellular amastigote forms, nitric oxide (NO) and TNF-α production were also investigated. RESULTS: The exudate from the leaves afforded the novel icetexane 7-hydroxyfruticulin A (1) as well as the known demethylisofruticulin A (2), fruticulin A (3) and demethylfruticulin A (4). The compounds (1-4) were tested against promastigotes of L. amazonensis and showed an effective inhibition of the parasite survival (IC50 = 4.08-16.26 µM). In addition, they also induced mitochondrial ROS production, plasma membrane permeability and mitochondrial dysfunction in treated parasites, and presented low cytotoxicity against macrophages. Furthermore, all diterpenes tested reduced the number of parasites inside macrophages, by mechanisms involving TNF-α, NO and ROS. CONCLUSION: The results suggest the potential of 7-hydroxyfruticulin A (1) as well as the known demethylisofruticulin A (2),fruticulin A (3) and demethylfruticulin A (4) as candidates for use in further studies on the design of anti-leishmanial drugs.

Anti-adhesive, anti-biofilm and fungicidal action of newly synthesized gemini quaternary ammonium salts.

Newly synthesized gemini quaternary ammonium salts (QAS) with different counterions (bromide, hydrogen chloride, methylcarbonate, acetate, lactate), chain lengths (C12, C14, C16) and methylene linker (3xCH2) were tested. Dihydrochlorides and dibromides with 12 carbon atoms in hydrophobic chains were characterized by the highest biological activity against planktonic forms of yeast and yeast-like fungi. The tested gemini surfactants also inhibited the production of filaments by C. albicans. Moreover, they reduced the adhesion of C. albicans cells to the surfaces of stainless steel, silicone and glass, and slightly to polystyrene. In particular, the gemini compounds with 16-carbon alkyl chains were most effective against biofilms. It was also found that the tested surfactants were not cytotoxic to yeast cells. Moreover, dimethylcarbonate (2xC12MeCO3G3) did not cause hemolysis of sheep erythrocytes. Dihydrochlorides, dilactate and diacetate showed no mutagenic potential.

Hump-Nosed Pit Viper (Hypnale hypnale) Venom-Induced Irreversible Red Blood Cell Aggregation, Inhibition by Monovalent Anti-Venom and N-Acetylcysteine.

Envenomation by the Hypnale hypnale in the Western Ghats of India (particularly in the Malabar region of Kerala) and the subcontinent island nation of Sri Lanka is known to inflict devastating mortality and morbidity. Currently, H. hypnale bites in India are devoid of anti-venom regimens. A detailed characterization of the venom is essential to stress the need for therapeutic anti-venom. Notably, the deleterious effects of this venom on human blood cells have largely remained less explored. Therefore, in continuation of our previous study, in the present study, we envisioned investigating the effect of venom on the morphological and physiological properties of red blood cells (RBCs). The venom readily induced deleterious morphological changes and, finally, the aggregation of washed RBCs. The aggregation process was independent of the ROS and the intracellular Ca2+ ion concentration. Confocal and scanning electron microscopy (SEM) images revealed the loss of biconcave morphology and massive cytoskeletal disarray. Crenation or serrated plasma membrane projections were evenly distributed on the surface of the RBCs. The venom did not cause the formation of methemoglobin in washed RBCs but was significantly induced in whole blood. Venom did not affect glucose uptake and Na+/K+ -ATPase activity but inhibited glucose 6 phosphate dehydrogenase activity and decreased the fluidity of the plasma membrane. Venom-induced RBC aggregates exhibited pro-coagulant activity but without affecting platelet aggregation. In pre-incubation or co-treatment studies, none of the bioactive compounds, such as melatonin, curcumin, fisetin, berberine, and quercetin, sugars such as mannose and galactose, and therapeutic polyvalent anti-venoms (Bharat and VINS) were inhibited, whereas only N-acetylcysteine and H. hypnale monovalent anti-venom could inhibit venom-induced deleterious morphological changes and aggregation of RBCs. In post-treatment studies, paradoxically, none of the bioactives and anti-venoms, including N-acetylcysteine and H. hypnale monovalent anti-venom, reversed the venom-induced RBC aggregates.

Mechanisms Underlying the Effects of Chloroquine on Red Blood Cells Metabolism.

Chloroquine (CQ) is a 4-aminoquinoline derivative largely employed in the management of malaria. CQ treatment exploits the drug's ability to cross the erythrocyte membrane, inhibiting heme polymerase in malarial trophozoites. Accumulation of CQ prevents the conversion of heme to hemozoin, causing its toxic buildup, thus blocking the survival of Plasmodium parasites. Recently, it has been reported that CQ is able to exert antiviral properties, mainly against HIV and SARS-CoV-2. This renewed interest in CQ treatment has led to the development of new studies which aim to explore its side effects and long-term outcome. Our study focuses on the effects of CQ in non-parasitized red blood cells (RBCs), investigating hemoglobin (Hb) functionality, the anion exchanger 1 (AE1) or band 3 protein, caspase 3 and protein tyrosine phosphatase 1B (PTP-1B) activity, intra and extracellular ATP levels, and the oxidative state of RBCs. Interestingly, CQ influences the functionality of both Hb and AE1, the main RBC proteins, affecting the properties of Hb oxygen affinity by shifting the conformational structure of the molecule towards the R state. The influence of CQ on AE1 flux leads to a rate variation of anion exchange, which begins at a concentration of 2.5 µM and reaches its maximum effect at 20 µM. Moreover, a significant decrease in intra and extracellular ATP levels was observed in RBCs pre-treated with 10 µM CQ vs. erythrocytes under normal conditions. This effect is related to the PTP-1B activity which is reduced in RBCs incubated with CQ. Despite these metabolic alterations to RBCs caused by exposure to CQ, no signs of variations in oxidative state or caspase 3 activation were recorded. Our results highlight the antithetical effects of CQ on the functionality and metabolism of RBCs, and encourage the development of new research to better understand the multiple potentiality of the drug.

Ginseng total saponin improves red blood cell oxidative stress injury by regulating tyrosine phosphorylation and glycolysis in red blood cells.

BACKGROUND: Oxidative stress is the main cause of many diseases, but because of its complex pathogenic factors, there is no clear method for treating it. Ginseng total saponin (GTS) an important active ingredients in Panax ginseng C.A. Mey (PG) and has potential therapeutic ability for oxidative stress due to various causes. However, the molecular mechanism of GTS in the treating oxidative stress damage in red blood cells (RBCs) is still unclear. PURPOSE: This study aimed to examine the protective effect of GTS on RBCs under oxidative stress damage and to determine its potential mechanism. METHODS: The oxidative stress models of rat RBCs induced by hydrogen peroxide (H2O2) and exhaustive swimming in vivo and in vitro was used. We determined the cell morphology, oxygen carrying capacity, apoptosis, antioxidant capacity, and energy metabolism of RBCs. The effect of tyrosine phosphorylation (pTyr) of Band 3 protein on RBCs glycolysis was also examined. RESULTS: GTS reduced the hemolysis of RBCs induced by H2O2 at the lowest concentration. Moreover, GTS effectively improved the morphology, enhanced the oxygen carrying capacity, and increased antioxidant enzyme activity, adenosine triphosphate (ATP) levels, and adenosine triphosphatase (ATPase) activity in RBCs. GTS also promoted the expression of membrane proteins in RBCs, inhibited pTyr of Band 3 protein, and further improved glycolysis, restoring the morphological structure and physiological function of RBCs. CONCLUSIONS: This study shows, that GTS can protect RBCs from oxidative stress damage by improving RBCs morphology and physiological function. Changes in pTyr expression and its related pTyr regulatory enzymes before and after GTS treatment suggest that Band 3 protein is the main target of GTS in the treating endogenous and exogenous oxidative stress. Moreover, GTS can enhance the glycolytic ability of RBCs by inhibiting pTyr of Band 3 protein, thereby restoring the function of RBCs.

Biphasic dose-response and effects of near-infrared photobiomodulation on erythrocytes susceptibility to oxidative stress in vitro.

The effect of simultaneous application of tert-butyl hydroperoxide (tBHP) and polychromatic near-infrared (NIR) radiation on bovine blood was examined to determine whether NIR light decreases the susceptibility of red blood cells (RBCs) to oxidative stress. The study assessed various exposure methods, wavelength ranges, and optical filtering types. Continuous NIR exposure revealed a biphasic response in cell-free hemoglobin changes, with antioxidative effects observed at low fluences and detrimental effects at higher fluences. Optimal exposure duration was identified between 60 s and 15 min. Protective effects were also tested across wavelengths in the range of 750-1100 nm, with all of them reducing hemolysis, notably at 750 nm, 875 nm, and 900 nm. Comparing broadband NIR and far-red light (750 nm) showed no significant difference in hemolysis reduction. Pulse-dosed NIR irradiation allowed safe increases in radiation dose, effectively limiting hemolysis at higher doses where continuous exposure was harmful. These findings highlight NIR photobiomodulation's potential in protecting RBCs from oxidative stress and will be helpful in the effective design of novel medical therapeutic devices.

Bioinspired green synthesis of ZnO nanoparticles by marine-derived Streptomyces plicatus and its multifaceted biomedicinal properties.

The present study explores the bioinspired green synthesis of zinc oxide nanoparticles (ZnONPs) using marine Streptomyces plicatus and its potent antibacterial, antibiofilm activity against dental caries forming Streptococcus mutans MTCC and S. mutans clinical isolate (CI), cytotoxicity against oral KB cancer cells, hemolysis against blood erythrocytes and artemia toxicity. The bioinspired ZnONPs showed a distinctive absorption peak at 375 nm in UV-Vis spectra, the FT-IR spectra divulged the active functional groups, and XRD confirmed the crystalline nature of the nanoparticles with an average grain size of 41.76 nm. SEM analysis evidenced hexagonal morphology, and EDX spectra affirmed the presence of zinc. The ZnONPs exerted higher antagonistic activity against S. mutans MTCC (Inhibitory zone: 19 mm; MIC: 75 µg/ml) than S. mutans CI (Inhibitory zone: 17 mm; MIC: 100 µg/ml). Results of biofilm inhibitory activity showed a concentration-dependent reduction with S. mutans MTCC (15 %-95 %) more sensitive than S. mutans CI (13 %-89 %). The 50 % biofilm inhibitory concentration (BIC50) of ZnONPs against S. mutans MTCC was considerably lower (71.76 µg/ml) than S. mutans CI (78.13 µg/ml). Confocal Laser Scanning Microscopic visuals clearly implied that ZnONPs effectively distorted the biofilm architecture of both S. mutans MTCC and S. mutans CI. This was further bolstered by a remarkable rise in protein leakage (19 %-85 %; 15 %-77 %) and a fall in exopolysaccharide production (34 mg-7 mg; 49 mg-12 mg). MTT cytotoxicity of ZnONPs recorded an IC50 value of 22.06 µg/ml against KB cells. Acridine orange/ethidium bromide staining showed an increasing incidence of apoptosis in KB cells. Brine shrimp cytotoxicity using Artemia salina larvae recorded an LC50 value of 78.41 µg/ml. Hemolysis assay substantiated the biocompatibility of the ZnONPs. This study underscores the multifaceted application of bioinspired ZnONPs in dentistry.

A Quantitative Human Red Blood Cell Agglutination Assay for Characterisation of Galectin Inhibitors.

Galectins are a family of beta-galactoside-binding proteins that are characterised by their carbohydrate recognition domain (CRD) and include galectin-1 and galectin-3. These galectins have been implicated in numerous diseases due to their pleiotropic nature, including cancer and fibrosis, with therapeutic inhibitors being clinically developed to block the CRD. One of the early methods developed to characterise these galectins was the hemagglutination of red blood cells. Although it is insightful, this approach has been hampered by a lack of sensitivity and accurate quantification of the agglutination observed. In this study, we aimed to validate a more precise and quantitative method to enable the further investigation of differences between galectins in respect to agglutination induction in different blood groups, as well as the characterisation of small molecule inhibitors. Quantification of hemagglutination was shown to be optimal using U-bottom plates imaged and analysed with FIJI ImageJ rather than flat-bottom plates read for absorbance on an optical density plate reader. Galectin-3-induced red blood cell agglutination efficacy increased significantly from blood group O to A to B. However, for both the galectin-1 monomer and concatemer, a more comparable effect was observed between blood group B and O, but with more potent effects than in blood group A. Inhibition assays for both galectin-3 and galectin-1 induced-hemagglutination were able to demonstrate clear concentration responses and expected selectivity profiles for a set of small-molecule glycomimetics, confirming the historical profiles obtained in biochemical binding and functional cellular assays.

Toxicokinetic relationship between the adducts in globin and their cleavage products in the urine: Implications for human biomonitoring.

Globin adducts of various chemicals, persisting in organism over the whole lifetime of erythrocytes, have been used as biomarkers of cumulative exposures to parent compounds. After removal of aged erythrocytes from the bloodstream, cleavage products of these adducts are excreted with urine as alternative, non-invasively accessible biomarkers. In our biomonitoring studies on workers exposed to ethylene oxide, its adduct with globin, N-(2-hydroxyethyl)valine, and the related urinary cleavage product N-(2-hydroxyethyl)-L-valyl-L-leucine have been determined. To describe a toxicokinetic relationship between the above types of biomarkers, a general compartmental model for simulation of formation and removal of globin adducts has been constructed in the form of code in R statistical computing environment. The essential input variables include lifetime of erythrocytes, extent of adduct formation following a single defined exposure, and parameters of exposure scenario, while other possible variables are optional. It was shown that both biomarkers reflect the past exposures differently as the adduct level in globin is a mean value of adduct levels across all compartments (subpopulations of erythrocytes of the same age) while excretion of cleavage products reflects the adduct level in the oldest compartment. Application of the model to various scenarios of continuous exposure demonstrated its usefulness for human biomonitoring data interpretation.