The modulation of erythrocyte Na(+)/K(+)-ATPase activity by curcumin

Activity of Na+/K+- and Ca2+-ATPases in human erythrocyte membranes: Protocol improvement, relation to cholesterol content, and effects of polyphenols

It is known that the activities of Na+/K+- and Ca2+-ATPases in the plasma membrane with an excess of cholesterol are compromised. Our main goal was to find out whether quercetin, resveratrol, or caffeic acid, in the nano- and low micromolar concentration ranges, can improve the ATPase activity in human erythrocyte membranes with excess cholesterol. These molecules belong to different chemical classes of polyphenols and are widely present in plant foods. Also, due to some variations in the protocol for determining the ATPase activity, we first analyzed several key parameters of the protocol to improve the accuracy of the results. The activities of Na+/K+- and Ca2+-ATPases were reduced in membranes with moderate and high cholesterol levels compared to membranes from normocholesterolemic subjects (p < 0.01). All three polyphenols affected the ATPase activity in a similar biphasic manner. Namely, the ATPase activity gradually increased with increasing polyphenol concentration up to 80-200 nM, and then gradually decreased with further increase in polyphenol concentration. Moreover, the stimulating effect of the polyphenols was highest in membranes with high cholesterol content, making ATPase activity values close/equal to those in normal cholesterol membranes. In other words, quercetin, resveratrol, and caffeic acid at nanomolar concentrations were able to improve/restore the functioning of Na+/K+- and Ca2+-ATPases in erythrocyte membranes with high cholesterol levels. This suggests a common membrane-mediated mechanism of action for these polyphenols, related to the content of membrane cholesterol.

Curcumin from Curcuma longa Linn. (Family: Zingiberaceae) attenuates hypochlorous acid-induced cytotoxicity and oxidative damage to human red blood cells

Hypochlorous acid (HOCl) is a major oxidant produced by activated neutrophils via the myeloperoxidase catalyzed reaction. The production of HOCl eliminates a wide range of pathogens. However, HOCl can also cause significant oxidative damage in cells and tissues where it is generated. The protective effect of curcumin was studied on HOCl-induced oxidative damage to human red blood cells (RBC). Isolated RBC were incubated with HOCl at 37 °C in absence or presence of different concentrations of curcumin. Hemolysates were prepared and assayed for various biochemical parameters. Treatment of RBC with HOCl alone increased hemolysis, protein carbonyls, heme degradation and chloramines as compared to untreated control cells. This was accompanied by reduction in glutathione level, total sulfhydryls and free amino groups. HOCl also lowered the activities of major antioxidant enzymes and diminished the antioxidant power of RBC. Pre-treatment of RBC with different concentrations of curcumin resulted in concentration-dependent attenuation in all these parameters while curcumin alone had no significant effect. Scanning electron microscopy showed that curcumin prevented HOCl-induced morphological changes in RBC and restored their normal biconcave shape. Thus curcumin can be used as a chemoprotective agent to mitigate HOCl-induced oxidative damage to cells. These results also explain the beneficial effects of curcumin against Helicobacter pylori induced stomach ulcers, caused by excessive production of HOCl at the site of bacterial infection.

Decreased Na+/K+ pump activity in the erythrocyte membrane due to malondialdehyde in rheumatoid arthritis: an in vivo and in silico study

Apart from demonstrating the interaction behavior of malondialdehyde (MDA) with Na⁺/K⁺-ATPase using in silico, the current study aims to investigate the effect of rheumatoid arthritis-related oxidative stress on Na⁺/K⁺-ATPase activity that is present in the erythrocyte cell membrane, which is rich in proteins vulnerable to damage from MDA and other free radicals. The target population of this study consists of 28 rheumatoid arthritis patients and 20 healthy volunteers whose MDA levels and Na⁺/K⁺-ATPase activity were determined. It was shown that MDA levels of rheumatoid arthritis patients increased (p < 0.001) and their Na⁺/K⁺-ATPase activity noticeably decreased when compared to those of healthy individuals. Also, according to this in silico modeling, MDA decreased Na⁺/K⁺-ATPase activity in line with the correlation analyses. Consequently, while elevated levels of MDA in the rheumatoid arthritis group were suggestive of oxidative stress, a decreased Na⁺/K⁺-ATPase-activity led us to speculate that the cellular membrane had sustained injury. Therefore, our results could be useful in explaining how MDA affects Na⁺/K⁺-ATPase activity in the interior of a specific molecular pathway.

Baicalein may act as a caloric restriction mimetic candidate to improve the anti-oxidant profile in a natural rodent model of aging

INTRODUCTION

Caloric restriction (CR) is the most effective intervention for extending the life span of vertebrate and invertebrate aging models.. CRMs, which are synthetic or natural chemicals that mimic the biochemical, hormonal, and physiological consequences of calorie restriction, are being researched for anti-aging benefits. Baicalein is a plant-derived polyphenol that has the potential of anti-oxidant, anti-inflammatory, and autophagy inducer. The objective of this study is to evaluate the anti-aging, anti-inflammatory, and antioxidant role of Baicalein in erythrocyte membrane and plasma, and evaluate the efficacy of Baicalein to act as a CRM candidate.

MATERIALS AND METHODS

The present study evaluates the effect of Baicalein on aging biomarkers in normal and aged rats. We study various pro- and anti-oxidant markers, erythrocyte membrane transporters, and eryptosis.

RESULTS

Baicalein supplementation in male Wistar rats significantly alleviated pro-oxidant markers and improved anti-oxidant profile. Improvement was also observed in age-induced alterations in membrane transporters, and eryptosis.

CONCLUSION

Based on the above observations we conclude that Baicalein has the potential to maintain extracellular ROS levels and redox homeostasis during the aging process, an effect which is similar to CR. Thus Baicalein may be a potent CRM candidate for anti-aging interventions.

The Effects of Curcumin Plus Piperine Supplementation in Patients with Acute Myocardial Infarction: A Randomized, Double-Blind, and Placebo-Controlled Trial

BACKGROUND

Acute myocardial infarction (AMI) is a leading cause of death and disability worldwide. Previous investigations have demonstrated that curcumin has a cardioprotective effect and may improve myocardial injury. So this study was performed to assess whether supplementation with curcumin could diminish myocardial injury following AMI.

METHODS

To conduct this randomized, double-blinded, and placebo-controlled clinical trial, seventy-two patients with acute myocardial infarction, aged 18-75 years, were enrolled and randomly divided into the active intervention and control groups. The active intervention group (n = 38) received curcumin capsules with piperine supplement (500 mg/day, 95% curcuminoids) for 8 weeks, whereas the control group (n = 34) received a placebo capsule. At the baseline and end of the study, ejection fraction was assessed, and blood samples were taken from all patients to measure the levels of cardiac troponin I(cTnI), lipid profile, FBG, HbA1C, liver enzymes, renal function parameters, and electrolytes.

RESULTS

In this trial, curcumin supplementation significantly reduced the levels of HbA1C (-0.3 ± 2.2 vs. +1.1 ± 1.3, P = 0.002), LDL (-10.3 ± 20.7 vs. +0.2 ± 22.5, P = 0.039), ALT (-10.2 ± 28.5 vs. +7.3 ± 39.2, P = 0.029), and ALP (+6.4 ± 39.5 vs. +38.0 ± 69.0, P = 0.018) compared to the placebo group. Moreover, the serum concentration of HDL significantly improved in comparison with the placebo group (+4.5 ± 8.9 vs. -1.6 ± 7.7, P = 0.002). However, no substantial difference was perceived between the groups regarding the ejection fraction and serum levels of cTnI, FBG, renal function parameters, and electrolytes.

CONCLUSION

Our results indicated that daily intake of 500 mg of curcumin capsules with piperine supplement for 8 weeks modified lipid profile, liver enzymes, and glycemic status, but did not have any effect on ejection fraction and serum concentration of cardiac troponin I, renal function parameters, and electrolytes in acute myocardial infarction patients.

Erythrocyte Deformability and Na,K-ATPase Activity in Various Pathophysiological Situations and Their Protection by Selected Nutritional Antioxidants in Humans

The physicochemical and functional properties of erythrocytes are worsened in a variety of diseases. Erythrocyte deformability refers to their ability to adjust their shape according to external forces exerted against them in the circulation. It is influenced by the functionality of the Na,K-ATPase enzyme, which is localized in their membranes. The proposed review is focused on knowledge regarding changes in erythrocyte Na,K-ATPase activity, and their impact on erythrocyte deformability in various pathophysiological situations observed exclusively in human studies, as well as on the potential erytroprotective effects of selected natural nutritional antioxidants. A clear link between the erythrocyte properties and the parameters of oxidative stress was observed. The undesirable consequences of oxidative stress on erythrocyte quality and hemorheology could be at least partially prevented by intake of diverse antioxidants occurring naturally in foodstuffs. Despite intensive research concerning the effect of antioxidants, only a small number of investigations on erythrocyte properties in humans is available in databases. It is worth shifting attention from animal and in vitro experiments and focusing more on antioxidant administration in human studies in order to establish what type of antioxidant, in what concentration, and in which individuals it may provide a beneficial effect on the human organism, by protecting erythrocyte properties.

The Effect of Curcumin Nanoparticles on Cisplatin-Induced Cardiotoxicity in Male Wistar Albino Rats

The cardiotoxicity of chemotherapeutic drugs as cisplatin has become a major issue in recent years. The present study investigates the efficacy of curcumin nanoparticles against the cardiotoxic effects of cisplatin by assessment of oxidative stress parameters, Na+,K+-ATPase, acetylcholinesterase (AchE) and tumor necrosis factor-alpha (TNF-α) in cardiac tissue in addition to serum lactate dehydrogenase (LDH). Rats were divided into three groups: control rats that received saline for 14 days; cisplatin-treated rats that received a single intraperitoneal (i.p.) injection of cisplatin (12 mg/kg) followed by a daily oral administration of saline (0.9%) for 14 days and rats treated with a single i.p. injection of cisplatin (12 mg/kg) followed by a daily oral administration of curcumin nanoparticles (50 mg/kg) for 14 days. Cisplatin resulted in a significant increase in lipid peroxidation, nitric oxide (NO), and TNF-α and a significant decrease in reduced glutathione (GSH) levels and Na+, K+- ATPase activity. Moreover, significant increases in cardiac AchE and serum lactate dehydrogenase activities were recorded. Treatment of cisplatin-injected animals with curcumin nanoparticles ameliorated all the alterations induced by cisplatin in the heart of rats. This suggests that curcumin nanoparticles can be used as an important therapeutic adjuvant in chemotherapeutic and other toxicities mediated by oxidative stress and inflammation.

Pre-exposure of voglibose exerts cerebroprotective effects through attenuating activation of the polyol pathway and inflammation

Chronic hyperglycemia induces activation of the polyol-sorbitol pathway, which is a major contributor to microvascular complications like stroke. The current study was designed to elucidate the therapeutic role of α-glucose inhibitor in chronic hyperglycemia-induced impaired polyol pathway and associated micro-complications. Male albino-Wistar rats (200-250 g) were treated with voglibose 10 mg kg^-1  day^-1 /p.o. for 2 weeks before middle cerebral artery occlusion; 72 hr after surgery, neurological score was evaluated and blood was collected for the assessment of various serum biochemical parameters like CRP, CK-MB, LDH, lipid profile, and blood glucose levels. In the end, brain samples were excised for determination of brain infarct volume, brain hemisphere weight difference, Na+-K+ ATPase activity oxidative stress-related parameters, aldose reductase activity, and gene expression studies. Results from the present study indicate that pre-treatment with voglibose showed significant improvement in lipid parameters but did not impact glucose levels. Voglibose has shown a statistically significant (p < .05) reduction in neurological score and brain infarct volume, and the difference in brain hemisphere weight as compared to the disease control group. Voglibose significantly (p < .05) improve all biochemical parameters and reduced Na+-K+ ATPase and aldose reductase activity. Moreover, voglibose produced a significant reduction in oxidative stress and down-regulation of TNF-α and BCl-2 gene expression which reduces the risk of factors related to stroke. In conclusion, the pleiotropic effect of voglibose on cerebrovascular complications may be due to inhibition of aldose reductase or anti-inflammatory pathways.

Curcumin Sensitizes Kidney Cancer Cells to TRAIL-Induced Apoptosis via ROS Mediated Activation of JNK-CHOP Pathway and Upregulation of DR4

Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), is a selective anticancer cytokine capable of exerting a targeted therapy approach. Disappointingly, recent research has highlighted the development of TRAIL resistance in cancer cells, thus minimising its usefulness in clinical settings. However, several recent studies have demonstrated that cancer cells can be sensitised to TRAIL through the employment of a combinatorial approach, utilizing TRAIL in conjunction with other natural or synthetic anticancer agents. In the present study, the chemo-sensitising effect of curcumin on TRAIL-induced apoptosis in renal carcinoma cells (RCC) was investigated. The results indicate that exposure of kidney cancer ACHN cells to curcumin sensitised the cells to TRAIL, with the combination treatment of TRAIL and curcumin synergistically targeting the cancer cells without affecting the normal renal proximal tubular epithelial cells (RPTEC/TERT1) cells. Furthermore, this combination treatment was shown to induce caspase-dependent apoptosis, inhibition of the proteasome, induction of ROS, upregulation of death receptor 4 (DR4), alterations in mitogen-activated protein kinase (MAPK) signalling and induction of endoplasmic reticulum stress. An in vivo zebrafish embryo study demonstrated the effectiveness of the combinatorial regime to inhibit tumour formation without affecting zebrafish embryo viability or development. Overall, the results arising from this study demonstrate that curcumin has the ability to sensitise TRAIL-resistant ACHN cells to TRAIL-induced apoptosis.

Association between a novel G94A single nucleotide polymorphism in ATP1A1 gene and type 2 diabetes mellitus among Egyptian patients

Background:

Na⁺/K⁺ ATPase enzyme is essential for nerve cell membrane integrity, and reduction in its activity, probably due to ATP1A1 gene polymorphisms, is related to diabetic neuropathy progression. Therefore, the goal of the existent study is to evaluate the Na⁺/K⁺ ATPase activity in type 2 diabetes mellitus (T2DM) Egyptian patients with or without neuropathy, search for polymorphism(s) in the highly polymorphic region of ATP1A1 gene, exon 2, and study its (their) associations with T2DM with and without neuropathy.

Materials and Methods:

A total number of 150 individuals were subclassified into healthy controls (n = 30), T2DM without complications (n = 60), and T2DM with neuropathy (n = 60).

Results:

The biochemical results exhibited a significant reduction in fasting C-Peptide and activity of Na⁺/K⁺ ATPase in T2DM patients with neuropathy followed by T2DM without complication in comparison with healthy controls. ATP1A1 exon2 was amplified by polymerase chain reaction (PCR) then digested by the PstI restriction enzyme, and the obtained data from restriction fragment length polymorphism-PCR and sequencing revealed the existence of a novel synonymous G94A single nucleotide polymorphism (SNP) at nucleotide 27 in exon 2 of ATP1A1 gene (rs1060366). Diabetic groups had only allele A, while the control group had G allele. Interestingly, individuals carrying AA genotype had a significantly lower Na⁺/K⁺ ATPase, C-peptide, and higher glycosylated hemoglobin (HBA1c %) than those having GG genotype, suggesting a possible association for this SNP, and this developed phenomenon of not only T2DM but also diabetic neuropathy.

Conclusion:

Thus, allele A of G94A SNP (rs1060366) could be a risk allele for diabetes susceptibility among Egyptian patients.

Protective Effects and Mechanism of Meretrix meretrix Oligopeptides against Nonalcoholic Fatty Liver Disease

Meretrix meretrix oligopeptides (MMO) derived from shellfish have important medicinal properties. We previously obtained MMO from alcalase by hydrolysis processes. Here we examine the protective effects of MMO against nonalcoholic fatty liver disease (NAFLD) and explored the underlying mechanism. Human Chang liver cells were used in our experiments after exposure to palmitic acid at a final concentration of 15 μg/mL for 48 h to induce an overload of fatty acid as NAFLD model cells. Treatment with MMO for 24 h increased the viability of the NAFLD model cells by inhibiting apoptosis. MMO alleviated oxidative stress in the NAFLD model cells by preserving reactive oxygen species activity and increasing malondialdehyde and superoxide dismutase activity. MMO improved mitochondrial dysfunction by decreasing the mitochondrial membrane potential and increasing the activities of Na⁺/K⁺-ATPase and Ca²⁺/Mg²⁺-ATPase. In addition, MMO inhibited the activation of cell death-related pathways, based on reduced p-JNK, Bax expression, tumor necrosis factor-α, caspase-9, and caspase-3 activity in the NAFLD model cells, and Bcl-2 expression was enhanced in the NAFLD model cells compared with the control group. These findings indicate that MMO have antioxidant and anti-apoptotic effects on NAFLD model cells and may thus exert protective effects against NAFLD.

Resealed Erythrocytes as Drug Carriers and Its Therapeutic Applications

In this pharma innovative world, there are more than 30 drug delivery systems. Today's due to lacking the target specificity, the present scenario about drug delivery is emphasizing towards targeted drug delivery systems. Erythrocytes are the most common type of blood cells travel thousands of miles from wide to narrow pathways to deliver oxygen, drugs and nutrient during their lifetime. Red blood cells have strong and targeted potential carrier capabilities for varieties of drugs. Drug-loaded carrier erythrocytes or resealed erythrocytes are promising for various passive and active targeting. Resealed erythrocyte have advantage over several drug carrier models like biocompatibility, biodegradability without toxic products, inert intracellular environment, entrapping potential for a variety of chemicals, protection of the organism against toxic effects of the drug, able to circulate throughout the body, ideal zero-order drug-release kinetics, no undesired immune response against encapsulated drug etc. Resealed erythrocytes are rapidly taken up by macrophages of the Reticuloendothelial System (RES) of the liver, lung, and spleen of the body and hence drugs also. Resealed erythrocytes method of drugs delivery is secure and effective for drugs targeting specially for a longer period of time. This chapter will explain the different method of drug loading for resealed erythrocytes, their characterization, and applications in various therapies and associated health benefits.

Modulation of Erythrocyte Plasma Membrane Redox System Activity by Curcumin

Plasma membrane redox system (PMRS) is an electron transport chain system ubiquitously present throughout all cell types. It transfers electron from intracellular substrates to extracellular acceptors for regulation of redox status. Curcumin, isolated from Curcuma longa, has modulatory effects on cellular physiology due to its membrane interaction ability and antioxidant potential. The present study investigates the effect of curcumin on PMRS activity of erythrocytes isolated from Wistar rats in vitro and in vivo and validated through an in silico docking simulation study using Molegro Virtual Docker (MVD). Effects of curcumin were also evaluated on level of glutathione (GSH) and the oxidant potential of plasma measured in terms of plasma ferric equivalent oxidative potentials (PFEOP). Results show that curcumin significantly (p < 0.01) downregulated the PMRS activity in a dose-dependent manner. Molecular docking results suggest that curcumin interacts with amino acids at the active site cavity of cytochrome b 5 reductase, a key constituent of PMRS. Curcumin also increased the GSH level in erythrocytes and plasma while simultaneously decreasing the oxidant potential (PFEOP) of plasma. Altered PMRS activity and redox status are associated with the pathophysiology of several health complications including aging and diabetes; hence, the above finding may explain part of the role of curcumin in health beneficial effects.

Modulation Effects of Curcumin on Erythrocyte Ion-Transporter Activity

Curcumin ((1E,6E)-1,7-Bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), the yellow biphenolic pigment isolated from turmeric (Curcuma longa), has various medicinal benefits through antioxidation, anti-inflammation, cardiovascular protection, immunomodulation, enhancing of the apoptotic process, and antiangiogenic property. We explored the effects of curcumin in vitro (10⁻⁵ M to 10⁻⁸ M) and in vivo (340 and 170 mg/kg b.w., oral) on Na⁺/K⁺ ATPase (NKA), Na⁺/H⁺ exchanger (NHE) activity, and membrane lipid hydroperoxides (ROOH) in control and experimental oxidative stress erythrocytes of Wistar rats. As a result, we found that curcumin potently modulated the membrane transporters activity with protecting membrane lipids against hydro-peroxidation in control as well as oxidatively challenged erythrocytes evidenced by stimulation of NKA, downregulation of NHE, and reduction of ROOH in the membrane. The observed results corroborate membrane transporters activity with susceptibility of erythrocyte membrane towards oxidative damage. Results explain the protective mechanism of curcumin against oxidative stress mediated impairment in ions-transporters activity and health beneficial effects.