Erratum: Antibacterial Efficacy of ZnO/Bentonite (Clay) Nanocomposites against Multidrug-Resistant Escherichia coli.

[This corrects the article DOI: 10.1021/acsomega.3c07950.].

Antibacterial Efficacy of ZnO/Bentonite (Clay) Nanocomposites against Multidrug-Resistant Escherichia coli.

The emergence of multidrug-resistant (MDR) bacteria has spurred the exploration of therapeutic nanomaterials such as ZnO nanoparticles. However, the inherent nonspecific toxicity of ZnO has posed a significant obstacle to their clinical utilization. In this research, we propose a novel approach to improve the selectivity of the toxicity of ZnO nanoparticles by impregnating them onto a less toxic clay mineral, Bentonite, resulting in ZB nanocomposites (ZB NCs). We hypothesize that these ZB NCs not only reduce toxicity toward both normal and carcinogenic cell lines but also retain the antibacterial properties of pure ZnO nanoparticles. To test this hypothesis, we synthesized ZB NCs by using a precipitation technique and confirmed their structural characteristics through X-ray diffraction and Raman spectroscopy. Electron microscopy revealed composite particles in the size range of 20-50 nm. The BET surface area of ZB NCs, within a relative pressure (P/P0) range of 0.407-0.985, was estimated to be 31.182 m2/g. Notably, 50 mg/mL ZB NCs demonstrated biocompatibility with HCT 116 and HEK 293 cell lines, supported by flow cytometry and fluorescence microscopy analysis. In vitro experiments further confirmed a remarkable five-log reduction in the population of MDR Escherichia coli in the presence of 50 mg/mL of ZB NCs. Antibacterial activity of the nanocomposites was also validated in the HEK293 and HCT 116 cell lines. These findings substantiate our hypothesis and underscore the effectiveness of ZB NCs against MDR E. coli while minimizing nonspecific toxicity toward healthy cells.

Synthesis, characterization and application of BR@Ag nanocomposite material for high degree reduction of p-nitro phenol under a suitable condition.

One of the most essential chemical processes that is utilized in the manufacturing of a great deal of contemporary goods is called heterogeneously catalyzed reactions, and it is also one of the most fascinating. Metallic nanostructures are heterogeneous catalysts for range reactions due to their huge surface area, large assembly of active surface sites, and quantum confinement effects. Unprotected metal nanoparticles suffer from irreversible agglomeration, catalyst poisoning, and limited life cycle. To circumvent these technical disadvantages, catalysts are frequently spread on chemically inert materials like as mesoporous Al2O3, ZrO2, and different types of ceramic material. In this research, plentiful bauxite residue is used to create a low-cost alternative catalytic material. We have hydrogenated p-Nitrophenol to p-Aminophenol on bauxite residue (BR) supported silver nanocomposites (Ag NCs). The phase and crystal structure, bond structure and morphological analysis of the developed material will be done XRD, FTIR, and SEM-EDX respectively. The ideal conditions were 150 ppm of catalyst, 0.1 mM of p-NP, and 10 minutes overall up-to 99% conversion of p-NP to p-AP. A multi-variable predictive model created using Response Surface Methodology (RSM) and a data-based Artificial Neural Network (ANN) model were found to be the best ways to predict the maximum conversion efficiency. ANN models predicted efficiency more accurately than RSM models, and the strong agreement between model predictions and experimental data was indicated by their low relative error (RE0.10), high regression coefficient (R2>0.97), and Willmott-d index (dwill-index > 0.95) values.

Modeling the effect of climatic conditions and topography on malaria incidence using Poisson regression: a Retrospective study in Bannu, Khyber Pakhtunkhwa, Pakistan.

Background: Malaria has been identified as a crucial vector-borne disease around the globe. The primary aim of this study was to investigate the incidence of malaria in the district of Bannu and its relationship with climatic conditions such as temperature, rainfall, relative humidity, and topography. Methods: Secondary data were obtained from the metrological office and government hospitals across the district for 5 years (2013-2017). A Poisson regression model was applied for the statistical analysis. Results and discussion: The number of reported cases of malaria was 175,198. The regression analysis showed that temperature, relative humidity, and rainfall had a significant association (p < 0.05) with malaria incidence. In addition, the topographic variables were significantly associated (p < 0.05) with malaria incidence in the region. The percent variation in the odds ratio of incidence was 4% for every unit increase in temperature and 2% in humidity. In conclusion, this study indicated that the temperature, humidity, rainfall, and topographic variables were significantly associated with the incidence of malaria. Effective malaria control and interventions integrated with climatic factors must be considered to overcome the disease burden.

Fijian medicinal plants and their role in the prevention of Type 2 diabetes mellitus.

Medicinal plants (MPs) are natural sources of active compounds with potential therapeutic benefits in alleviating various illnesses for decades. Fijian people also are using these MPs for the management/prevention of Type 2 diabetes mellitus (T2DM) and associated complications. However, till date, none of these Fijian MP's antidiabetic potential have been explored or evaluated. Here, we investigated the antidiabetic potential of Fijian MPs scientifically. Phytochemicals such as polyphenols were detected to inhibit the activity of α-amylase and α-glucosidase, the two key carbohydrate enzymes linked to T2DM. Therefore, in the present study, the total phenolic content (TPC), α-amylase and α-glucosidase inhibitory activity of five Fijian MPs: Vobo (Mussaenda raiateensis, MR), Vula walu (Blechnum orientale, BO), Gasau (Miscanthus floridulus, MF), Molikaro (Citrus limon, CL) and Beki ni sina (Dicranopteris caudate, DC) collected from mainland region of Vitilevu, Fiji Islands, were evaluated in vitro. The hydromethanolic (ME) and dichloromethane (DM) extracts of these selected MPs were investigated. The ME extracts of BO (0.102 ± 0.009 mM CE) and DC (0.098 ± 0.09 mM Catechin Equivalence [CE]) showed a higher TPC compared with the control [vanillic acid (0.052 ± 0.003 mM CE, *P value < 0.05)]. However, the TPC of MF, MR and CL were found in the range of 0.020 ± 0.009 to 0.009 ± 0.01 mM CE. The ME extracts of MF and MR inhibited α-glucosidase significantly in comparison with acarbose as evidenced from the IC50 values (IC50 of MF = 1.58 ± 0.03 ng/µl; IC50 of MR = 1.87 ± 0.43 ng/µl and IC50 of acarbose = 3.34 ± 0.15 ng/µl). Moreover, DM extracts of MR (IC50 = 1.31 ± 0.29 ng/µl) also showed significantly higher α-glucosidase inhibitory activity. In contrary, MR (IC50 = 16.18 ± 0.16 ng/µl) and CL (IC50 = 9.21 ± 0.51 ng/µl) also showed significant α-amylase inhibitory activity in ME and DM extracts, respectively. These, results suggest that Fijian MPs could be a potential source of natural inhibitors of enzymes involved in carbohydrate digestion and thus may possibly be used in managing T2DM.

Key role of Extracellular RNA in hypoxic stress induced myocardial injury.

Myocardial infarction (MI), atherosclerosis and other inflammatory and ischemic cardiovascular diseases (CVDs) have a very high mortality rate and limited therapeutic options. Although the diagnosis is based on markers such as cardiac Troponin-T (cTrop-T), the mechanism of cTrop-T upregulation and release is relatively obscure. In the present study, we have investigated the mechanism of cTrop-T release during acute hypoxia (AH) in a mice model by ELISA & immunohistochemistry. Our study showed that AH exposure significantly induces the expression and release of sterile inflammatory as well as MI markers in a time-dependent manner. We further demonstrated that activation of TLR3 (mediated by eRNA) by AH exposure in mice induced cTrop-T release and Poly I:C (TLR3 agonist) also induced cTrop-T release, but the pre-treatment of TLR3 immuno-neutralizing antibody or silencing of Tlr3 gene or RNaseA treatment two hrs before AH exposure, significantly abrogated AH-induced Caspase 3 activity as well as cTrop-T release. Our immunohistochemistry and Masson Trichrome (MT) staining studies further established the progression of myocardial injury by collagen accumulation, endothelial cell and leukocyte activation and adhesion in myocardial tissue which was abrogated significantly by pre-treatment of RNaseA 2 hrs before AH exposure. These data indicate that AH induced cTrop-T release is mediated via the eRNA-TLR3-Caspase 3 pathway.

ACE/ACE2 balance might be instrumental to explain the certain comorbidities leading to severe COVID-19 cases.

The outbreak of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a global catastrophe. The elderly and people with comorbidity are facing a serious complication of the disease. The entry and infection strategy of SARS-CoV-2 in a host cell is raised by an amazing way of angiotensin-converting enzyme (ACE) 2 (ACE2) receptor recognition and imbalance of ACE/ACE2 in various organs, especially in the lungs. Here it has been discussed the role of interferon and protease during the receptor recognition (begining of infection) and followed by the impact of cytokine and hypoxia in the context of the balance of ACE/ACE2. It has also very concisely delineated the biochemistry and mechanism of ACE/ACE2 balance in different stages of infection and its role in comorbidity.

Coagulation Disorders in COVID-19: Role of Toll-like Receptors.

Coronavirus disease 2019 (COVID-19) has spread rapidly throughout the world. The range of the disease is broad but among hospitalized patients with COVID-19 are coagulation disorders, pneumonia, respiratory failure, and acute respiratory distress syndrome (ARDS). The excess production of early response proinflammatory cytokines results in what has been described as a cytokine storm, leading to an increased risk of thrombosis, inflammations, vascular hyperpermeability, multi-organ failure, and eventually death over time. As the pandemic is spreading and the whole picture is not yet clear, we highlight the importance of coagulation disorders in COVID-19 infected subjects and summarize it. COVID-19 infection could induce coagulation disorders leading to clot formation as well as pulmonary embolism with detrimental effects in patient recovery and survival. Coagulation and inflammation are closely related. In this review, we try to establish an association between virus infections associated with innate immune activation, inflammation and coagulation activation.

Hypoxia induced up-regulation of tissue factor is mediated through extracellular RNA activated Toll-like receptor 3-activated protein 1 signalling.

Sterile Inflammation (SI), a condition where damage associated molecular patterns (DAMPs) released from dying cells, leads to TLR (Toll-like receptor) activation and triggers hypoxemia in circulation leading to venous thrombosis (VT) through tissue factor (TF) activation, but its importance under acute hypoxia (AH) remains unexplored. Thus, we hypothesized that eRNA released from dying cells under AH activates TF via the TLR3-ERK1/2-AP1 pathway, leading to VT. Animals were exposed to stimulate hypoxia for 0-24 h at standard temperature and humidity. RNaseA and DNase1 were injected immediately before exposure. TLR3 gene silencing was performed through in vivo injection of TLR3 siRNA. 80 µg/kg BW of isolated eRNA and eDNA were injected 6 h prior to sacrifice. Antigens of TF pathway were determined by ELISA and TF activity by a chromogenic assay. AH exposure significantly induced release of SI markers i.e. eRNA, eDNA, HMGB1 and upregulated TLR3, ERK1/2 (Extracellular signal-regulated kinases), AP1 (Activator Protein-1) and TF, whereas RNaseA pre-treatment diminished the effect of AH, thus inhibiting TF expression as well as activity during AH. Hence, we propose a possible mechanism of AH-induced TF activation and thrombosis where RNaseA can become the novel focal point in ameliorating therapy for AH induced thrombosis.

Inhibition of snake venom induced sterile inflammation and PLA2 activity by Titanium dioxide Nanoparticles in experimental animals.

Sterile inflammation (SI) is an essential process in response to snakebite and injury. The venom induced pathophysiological response to sterile inflammation results into many harmful and deleterious effects that ultimately leads to death. The available treatment for snakebite is antiserum which does not provide enough protection against venom-induced pathophysiological changes like haemorrhage, necrosis, nephrotoxicity and often develop hypersensitive reactions. In order to overcome these hindrances, scientists around the globe are searching for an alternative therapy to provide better treatment to the snake envenomation patients. In the present study TiO2 (Titanium dioxide)-NPs (Nanoparticles) has been assessed for antisnake venom activity and its potential to be used as an antidote. In this study, the synthesis of TiO2-NPs arrays has been demonstrated on p-type Silicon Si < 100 > substrate (∼30 ohm-cm) and the surface topography has been detected by Field-emission scanning electron microscopy (FESEM). The TiO2-NPs successfully neutralized the Daboia russelii venom (DRV) and Naja kaouthia venom (NKV)-induced lethal activity. Viper venom induced haemorrhagic, coagulant and anticoagulant activities were effectively neutralized both in in-vitro and in vivo studies. The cobra and viper venoms-induced sterile inflammatory molecules (IL-6, HMGB1, HSP70, HSP90, S100B and vWF) were effectively neutralised by the TiO2-NPs in experimental animals.

PGE2 -induced migration of human brain endothelial cell is mediated though protein kinase A in cooperation of EP receptors.

PGE2 plays a critical role in angiogenesis, ischemic, and neuro-inflammatory disorders of the brain, which breakdown the blood-brain barrier (BBB). However, the effects of PGE2 on human brain endothelial cell (HBECs) migration, a key process in the angiogenic response and BBB stability, are not well defined. In this study, we investigated the mechanism of PGE2 in HBECs migration in vitro. Here we showed that PGE2 stimulated migration of HBECs in a dose-time and matrix-dependent manner, evaluated by the Boyden chamber assay, but other prostanoids failed to do so. PGE2 receptor (EP2; butaprost), EP3 (sulprostone), and EP4 (PGE1 -OH) receptor agonists stimulated HBECs migration, but the silencing of EP significantly attenuated this effect. EP1 agonist (11-trinor PGE1 ) had no effect on HBECs migration on silencing of the EP1 receptor. We further showed that PGE2 stimulated cAMP production and activated protein kinase A (PKA), whereas pretreatment with the adenyl cyclase inhibitor (dideoxyadenosine; 1 µM) or PKA inhibitors, H89 (0.5 µM)/PKAI (1 µM), completely abrogated PGE2 -induced migration. Furthermore, silencing of the EP2/EP4 receptors significantly inhibited PGE2 -induced cAMP and PKA activation, whereas EP3 receptor silencing failed to do so. These results suggest that PGE2 regulates HBEC migration via cooperation of EP2, EP3, and EP4 receptors. Coupling of PGE2 to these receptors resulted in increased production of cAMP, which regulates HBEC migration via PKA pathway. The elucidation of molecular events involved is critical for the development of targeted strategies to treat cerebrovascular diseases associated with dysregulated angiogenesis.

Antidiabetic role of a novel protein from garlic via NO in expression of Glut-4/insulin in liver of alloxan induced diabetic mice.

INTRODUCTION: Garlic has been reported to stimulate nitric-oxide (NO) synthesis in various cells. The role of aqueous-extract of garlic (AEG) and a purified NO-generating protein from garlic (NGPG) was investigated to control hyperglycemia by hepatic insulin synthesis through NGPG induced synthesis of NO via glucose-activated NO-synthase and glucose transporter-4 (Glut-4) in the hepatocytes. METHODS: Type-1-diabetic mellitus mice were prepared by alloxan treatment, NO was determined by methemoglobin method, insulin synthesis was quantitated by ELISA. TNF-α and NFκß was quantitated by ELISA. The AEG-induced Glut-4 synthesis was determined by in-vitro translation of mRNA from the hepatocytes. The NO-generating protein from AEG was purified to homogeneity by chromatography on DEAE-cellulose and Sephadex G-50 columns and sequenced/characterized by Mass-spectral-analysis. RESULTS: Purified NGPG injection to diabetic mice significantly reduced the blood-sugar and increase insulin level in diabetic animal. It also increases insulin-release, Glut-4 synthesis, glucose-uptake in both liver and ß-cells of diabetic mice. NGPG down regulated pro-inflammatory cytokine TNF-α and the stress responsive NFκB-expression in liver cell of diabetic mice. Injection of AEG to the diabetic mice reduced the blood glucose level from 550 ± 10 mg/dL to 125 ± 10 mg/dL in 16 h with simultaneous increase of plasma NO from 0 nmol/h to 2.5 nmol/h and insulin 2 ± 1.1µunit/mL to 15µunit/mL at 16 h. Oral administration of AEG to adult diabetic mice increased NO, insulin and Glut-4 synthesis in the hepatocytes. CONCLUSION: AEG and the purified-NGPG protein can control hyperglycemia through the stimulation of NO by glucose-activated NO-synthase that would play an important role in the synthesis of insulin/Glut-4 in liver-cells.

Sterile Inflammatory Role of High Mobility Group Box 1 Protein: Biological Functions and Involvement in Disease.

High mobility group box 1 protein (HMGB1), a sterile inflammatory molecule and damage-associated molecular pattern (DAMP) released from various cells during stress has been implicated in inflammation. Several reports show that there is a direct relationship between inflammation and cardiovascular diseases (CVDs) such as thrombosis, hypertension, insulin resistance, preeclampsia, etc. Here, we intend to summarize the concept of the emerging link between HMGB1 and CVDs. Furthermore, we will discuss the possible therapeutic strategies that target HMGB1 for the treatment of different CVDs.

Estriol Inhibits Dermcidin Isoform-2 Induced Inflammatory Cytokine Expression Via Nitric Oxide Synthesis in Human Neutrophil.

BACKGROUND: An increase in the level of cytokines like TNF-α and IL-6 causes the inflammatory surge in acute ischemic heart disease (AIHD). OBJECTIVE: A high-level dermcidin isoform-2 (DCN-2) occurrence in AIHD was subjected to determine a possible regulation of cytokines expression. The effect of estrogen to counteract the inflammatory response was determined. METHODS: Blood was collected from AIHD patients and normal volunteers with consent. Nitric oxide (NO) synthesis was done with methemoglobin method.TNF-α and IL-6 expression were determined by ELISA and Western blot. RESULTS: (DCN-2) incubation with 120nM to the normal neutrophil solution for 2h resulted in the increase of TNF-α from 3.82±1.53pg/ml to 20.7±6.9pg/ml and IL-6 from 3.27±1.52pg/ml to 47.07±3.4pg/ml. In AIHD patients, the cytokine level was18.3- 27.3pg/ml, with a median value 21.86pg/ml (TNF-α) and IL-6 level was 23.54- 52.73pg/ml, with a median value 42.16pg/ml. Treatment with 0.6nM estriol, a kind of female steroid hormone estrogen for 45min decreased the elevated cytokine level in 120nM DCN-2 treated normal neutrophils. DCN-2 induced TNF-α synthesis in neutrophils was further determined by Western blot technique with a thickened band intensity of TNF-α. Estriol (0.6nM) treatment also influenced the DCN-2 induced inhibition of nitric oxide (NO) synthesis from 0nmol NO/ml to 0.56nmol/ml. The subsequent reduction of TNF-α level correlates the increase of NO level. CONCLUSION: In conclusion, the stress-induced DCN-2 production in AIHD propagates the inflammatory response. Steroid molecule like estriol plays a protective role by reducing DCN-2 responses in the NO synthesis.

HMGB1 facilitates hypoxia-induced vWF upregulation through TLR2-MYD88-SP1 pathway.

Increased plasma level of von Willebrand Factor (vWF) is associated with major cardiovascular diseases. We previously reported that multimeric vWF binds to NO synthase and inhibits insulin-induced production of NO, thus promoting insulin resistance during acute hypoxia (AH). However, the transcriptional regulation of vWF during AH is not clearly understood. Here, we investigated the mechanisms underlying the upregulation of vwf in mice. AH significantly upregulates the tlr2, tlr3, myd88, and vwf expression and phosphorylation of specificity protein 1 (SP1). Furthermore, AH significantly upregulates high mobility group box-1 (HMGB1) in a time-dependent manner. Moreover, a TLR2 agonist upregulates vWF but a TLR3 agonist does not. Pretreatment with an HMGB1 inhibitor, TLR2-immunoneutralizing antibody, or SP1 inhibitor significantly inhibits vWF expression. Furthermore, Tlr2 silencing completely inhibited MYD88, vWF expression, and SP1 phosphorylation. However, pretreatment with glycyrrhizic acid or silencing of Tlr2 completely blocks binding of Sp1 to the Vwf promoter, thus inhibiting its expression, and enhances insulin resistance during AH. Patients with type 2 diabetes mellitus also showed significantly elevated levels of HMGB1, TLR2, SP1, and vWF, thereby supporting the results of the murine model of AH. Taken together, HMGB1 upregulates vWF in vivo through the TLR2-MYD88-SP1 pathway in mice.

The control of hyperglycemia by a novel trypsin resistant oral insulin preparation in alloxan induced type I diabetic mice.

A trypsin resistant oral insulin preparation was made by incubating insulin for 2 h at 23 °C with previously boiled cow milk at 100 °C that was coagulated with 0.6 M acetic acid. The precipitate was resuspended in the same volume of milk. The immunoblot analysis of the suspended proteins treated with 200 ng of trypsin/ml for 3 h demonstrated that the 80.1% of the insulin in the suspension survived the proteolytic degradation compared to 0% of the hormone survived in the control. The feeding of 0.4 ml (0.08 unit of insulin) of the resuspended proteins followed by 0.2 ml of the same protein to alloxan induced diabetic mice maximally decreased the blood glucose level from 508 ± 10 mg/dl to 130 ± 10 mg/dl in 7 h with simultaneous increase of the basal plasma concentration of insulin from 3 ± 1.1 µunits/ml to 18 ± 1.5 µunits/ml. In control experiment the absence of insulin in the identical milk suspension produced no hypoglycemic effect suggesting milk was not responsible for the hypoglycemic effect of milk-insulin complex. Coming out of insulin-casein complex from the intestinal gut to the circulation was spontaneous and facilitated diffusion transportation which was found from Gibbs free energy reaction.

Extracellular RNA facilitates hypoxia-induced leukocyte adhesion and infiltration in the lung through TLR3-IFN-γ-STAT1 signaling pathway.

Endogenous ligands released from dying cells, including extracellular RNA (eRNA), cause TLR activation, which is associated with inflammation and vascular diseases. However, the importance of this response in acute hypoxia (AH) remains unexplored. Here, we observed eRNA-mediated TLR3 activation during exposure of mice to AH in the absence of exogenous viral stimuli. RNaseA treatment diminished AH-induced expression of IFN and cell adhesion molecules (CAMs) and myeloid cell infiltration in the lung, and TLR3 gene silencing or neutralization with antibodies markedly attenuated AH- or poly I:C-induced IFN and CAM expression and leukocyte adhesion (LA) and myeloid cell infiltration in the lung. However, RNaseA treatment or TLR3 gene silencing failed to alter AH-induced cell death and proliferation in lung vasculature. Furthermore, IFN-γ--but not IFN-α--regulated AH-induced CAM expression and LA. Treatment with RNaseA, TLR3 siRNA, neutralizing antibodies, or a STAT1 inhibitor substantially decreased AH- and poly I:C-induced STAT1 phosphorylation, CAM expression, and myeloid cell infiltration, suggesting a central role for STAT1 phosphorylation in AH-induced LA and infiltration. We conclude that eRNA activates TLR3 and facilitates, through in vivo IFN-γ-STAT1 signaling, AH-induced leukocyte infiltration in the lung. Thus, RNaseA might provide a therapeutic alternative for patients with lung diseases.

von Willebrand factor antagonizes nitric oxide synthase to promote insulin resistance during hypoxia.

Hypoxic respiratory diseases or hypoxia exposures are frequently accompanied by glucose intolerance and impaired nitric oxide (NO) availability. However, the molecular mechanism responsible for impaired NO production and insulin resistance (IR) during hypoxia remains obscure. In this study, we investigated the possible mechanism of impaired NO production and IR during hypoxia in a mouse model. Mice were exposed to hypoxia for different periods of time (0-24 h), and parameters of IR and endothelial dysfunctions were analyzed. Exposure to hypoxia resulted in a time-dependent increase in IR as well as multimeric forms of von Willebrand factor (vWF) and subsequently a decrease in eNOS activity. Preincubation with plasma of hypoxia-exposed animals (different time points) or human vWF inhibited insulin-induced NO production in a dose-dependent manner; larger doses of insulin reversed the effect. In contrast, preincubation of vWF-immunodepleted plasma failed to inhibit insulin-induced NO production, whereas vWF immunoneutralization abolished the effect of hypoxia-induced IR and D-[U-(14)C]glucose uptake. Furthermore, the interactions between vWF and eNOS were studied by far-Western blotting, co-immunoprecipitation, and surface plasma resonance spectroscopy. Kinetic analyses showed that the dissociation constant (KD), inhibitory constant (Ki), and half-maximal inhibitory concentration (IC50) were 1.79 × 10(-8) M, 250 pM, and 18.31 pM, respectively, suggesting that vWF binds to eNOS with a high affinity and greater efficacy for activator (insulin) inhibition. These results indicated that vWF, an antagonist of eNOS, inhibits insulin-induced NO production and causes IR.

The activation by glucose of liver membrane nitric oxide synthase in the synthesis and translocation of glucose transporter-4 in the production of insulin in the mice hepatocytes.

INTRODUCTION: Glucose has been reported to have an essential role in the synthesis and secretion of insulin in hepatocytes. As the efflux of glucose is facilitated from the liver cells into the circulation, the mechanism of transportation of glucose into the hepatocytes for the synthesis of insulin was investigated. METHODS: Grated liver suspension (GLS) was prepared by grating intact liver from adult mice by using a grater. Nitric oxide (NO) was measured by methemoglobin method. Glucose transporter-4 (Glut-4) was measured by immunoblot technique using Glut-4 antibody. RESULTS: Incubation of GLS with different amounts of glucose resulted in the uptake of glucose by the suspension with increased NO synthesis due to the stimulation of a glucose activated nitric oxide synthase that was present in the liver membrane. The inhibition of glucose induced NO synthesis resulted in the inhibition of glucose uptake. Glucose at 0.02M that maximally increased NO synthesis in the hepatocytes led to the translocation and increased synthesis of Glut-4 by 3.3 fold over the control that was inhibited by the inhibition of NO synthesis. The glucose induced NO synthesis was also found to result in the synthesis of insulin, in the presence of glucose due to the expression of both proinsulin genes I and II in the liver cells. CONCLUSION: It was concluded that glucose itself facilitated its own transportation in the liver cells both via Glut-4 and by the synthesis of NO which had an essential role for insulin synthesis in the presence of glucose in these cells.

Diagnosis of essential hypertension in humans by the determination of plasma renal cortexin using enzyme-linked immunosorbent assay.

BACKGROUND: More than 90% of all hypertensive persons are reported to have essential hypertension (EH), a particular form of elevated blood pressure, for which no diagnostic test is currently available. The level of plasma renal (R) cortexin (PRC), a hypotensive protein produced in the kidney cortex cells, was reported to be reduced from 218 nM in the plasma of normotensive persons (NP) to 0 nM in the plasma of patients with EH. The feasibility of using the determination of PRC by enzyme-linked immunosorbent assay (ELISA) as a diagnostic test for EH was investigated. METHODS: The PRC was determined by ELISA using electrophoretically pure cortexin as the antigen. A total of 344 persons (male and female) with EH, with or without diabetes mellitus (DM), and receiving or not receiving any anti-hypertensive and/or anti-diabetic medication at presentation, as well as an equal number of age- and gender-matched NP participated in the study. RESULTS: All persons with EH, with or without co-existing DM, were found to have 0 nM PRC, regardless of whether they were receiving anti-hypertensive and anti-diabetic drugs, including those who had been taking these medications over an extended period of time (3 months). CONCLUSIONS: The determination of PRC as a marker protein by ELISA, a rapid method that can be carried out in any diagnostic laboratory, was shown to be suitable for the diagnosis of EH, even in those subjects who had co-existing DM and were receiving both anti-hypertensive and anti-diabetic medication.