Laila A. Eissa

Measurements of oxidative stress status and antioxidant activity in chronic leukaemia patients

There is an interactive relationship between leukaemia and oxidative stress. Leukaemic cells produce larger amounts of reactive oxygen species (ROS) than non‐leukaemic cells as they are under a continual state of oxidative siege. So, this study was performed on 20 patients with chronic leukaemia from the Oncology Centre, Mansoura University. We measured leucocytic H2O2 concentrations and lipid peroxidation as serum malondialdehyde (MDA) concentration, serum total antioxidant activity, plasma ascorbic acid and dehydroascorbic acid concentrations, blood reduced glutathione concentration, haemolysate G6PD activity, blood catalase activity, serum superoxide dismutase (SOD) activity and serum anti‐dsDNA concentration. We found that chronic leukaemia patients showed a significant increase (P < 0.05) in leucocytic H2O2, serum MDA concentration and total anti‐oxidant activity either before or after treatment as compared with control group. Also, there was a significant increase in the other parameters (glutathione, catalase and SOD) either before or after treatment, but we found a significant decrease in ascorbic acid concentration and G6PD activity. There was a significant increase in anti‐dsDNA concentration either before or after treatment. It can be concluded that leukaemic patients produce larger amounts of ROS than non‐leukaemic patients. Also, the increase in antioxidant activity in leukaemic patients is not high enough to counteract the harmful effects of free radicals. This scenario becomes worse after administration of chemotherapy.

ABT-702, an adenosine kinase inhibitor, attenuates inflammation in diabetic retinopathy

AIMS This study was undertaken to determine the effect of an adenosine kinase inhibitor (AKI) in diabetic retinopathy (DR). We have shown previously that adenosine signaling via A2A receptors (A2AAR) is involved in retinal protection from diabetes-induced inflammation. Here we demonstrate that AKI-enhanced adenosine signaling provides protection from DR in mice. MAIN METHODS We targeted AK, the key enzyme in adenosine metabolism, using a treatment regime with the selective AKI, ABT-702 (1.5mg/kg intraperitoneally twice a week) commencing at the beginning of streptozotocin-induced diabetes at the age of eight weeks. This treatment, previously demonstrated to increase free adenosine levels in vivo, was maintained until the age of 16 weeks. Retinal inflammation was evaluated using Western blot, Real-Time PCR and immuno-staining analyses. Role of A2AAR signaling in the anti-inflammation effect of ABT-702 was analyzed in Amadori-glycated-albumin (AGA)-treated microglial cells. KEY FINDINGS At 16 weeks, when diabetic mice exhibit significant signs of retinal inflammation including up-regulation of oxidative/nitrosative stress, A2AAR, ENT1, Iba1, TNF-α, ICAM1, retinal cell death, and down-regulation of AK, the ABT-702 treated group showed lower signs of inflammation compared to control animals receiving the vehicle. The involvement of adenosine signaling in the anti-inflammation effect of ABT-702 was supported by the TNF-α release blocking effect of A2AAR antagonist in AGA-treated microglial cells. SIGNIFICANCE These results suggest a role for AK in regulating adenosine receptor signaling in the retina. Inhibition of AK potentially amplifies the therapeutic effects of site- and event-specific accumulation of extracellular adenosine, which is of highly translational impact.

Potential roles of adenosine deaminase-2 in diabetic retinopathy

The early activation of microglia that induces retinal inflammation in DR may serve as a target for therapeutic intervention of DR. Our demonstration that retinal inflammation is attenuated via adenosine receptor A(2A)AR supports the hypothesis that a mechanism to maintain extracellular concentrations of adenosine important in normal physiology is impaired in DR. Extracellular concentrations of adenosine are regulated by the interplay of equiliberative nucleoside transporter (ENT)s with enzymes of adenosine metabolism including adenosine deaminase-1 (ADA1), adenosine kinase (AK) and CD73. In the vertebrates but not rodents, a macrophage-associated ADA2 is identified. The role of ADA2 is, therefore, understudied as the sequencing probes or antibodies to mouse ADA2 are not available. We identified increased ADA2 expression and activity in human and porcine retinas with diabetes, and in Amadori glycated albumin (AGA)- or hyperglycemia-treated porcine and human microglia. In rodent as well as porcine cells, modulation of TNF-α release is mediated by A(2A)AR. Quantitative analysis of normal and diabetic porcine retinas reveals that while the expression levels of ADA2, A2AAR, ENT1, TNF-α and MMP9 are increased, the levels of AK are reduced during inflammation as an endogenous protective mechanism. To determine the role of ADA2, we found that AGA induces ADA2 expression, ADA2 activity and TNF-α release, and that TNF-α release is blocked by ADA2-neutralizing antibody or ADA2 siRNA, but not by scrambled siRNA. These results suggest that retinal inflammation in DR is mediated by ADA2, and that the anti-inflammatory activity of A(2A)AR signaling is impaired in diabetes due to increased ADA2 activity.

Cepharanthine and Piperine ameliorate diabetic nephropathy in rats: role of NF-κB and NLRP3 inflammasome.

AIMS Hyperglycemia leads to elevation of oxidative stress and proinflammatory cytokines which are the main causes of diabetic nephropathy (DN). NLRP3 inflammasome and thioredoxin-interacting protein (TXNIP) are recently assumed to participate in the development of DN. We aimed to investigate the effects of Cepharanthine (CEP), Piperine (Pip) and their combination in streptozotocin (STZ)-induced DN focusing on their role to modulate NLRP3 and TXNIP induced inflammation. MAIN METHODS Diabetic rats were treated with intraperitoneal (i.p.) injection of CEP (10mg/kg/day), Pip (30mg/kg/day) or their combination for 8weeks. Nuclear factor kappa B (NF-κB), tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β) were assessed by ELISA technique. TXNIP and NLRP3 genes expressions were evaluated by real time-PCR. KEY FINDINGS Diabetic rats showed significant increase in renal TXNIP and NLRP3 expression. CEP, Pip or their combination significantly decreased TXNIP and NLRP3 expression in diabetic kidneys. Hyperglycemia induced NF-κB activation leading to increased IL-1β and TNF-α levels. CEP, Pip or their combination showed significant inhibition of NF-κB together with decreased IL-1β and TNF-α levels in diabetic rats. Also, diabetic rats showed significant decrease in creatinine clearance and increase in blood glucose, serum creatinine, blood urea nitrogen, malondialdehyde, proteinuria, and kidney weight to body Weight ratio. All of these changes were reversed by CEP, Pip or their combination. SIGNIFICANCE The antioxidant and anti-inflammatory effects of CEP and Pip which were accompanied by inhibition of NF-κB and NLRP3 activation might be helpful mechanisms to halt the progression of DN.

Hepatoprotective effects of glycyrrhizin and omega-3 fatty acids on Nuclear Factor-kappa B pathway in thioacetamide-induced fibrosis in rats

Abstract Nuclear Factor kappa B (NF-κB) is a key transcriptional regulator that plays important roles in the pathogenesis of hepatic inflammation and fibrosis in chronic liver diseases. NF-κB activation leads to production of pro-inflammatory and fibrogenic cytokines. Glycyrrhizin (GL) is reported to suppress liver fibrosis and cirrhosis. Omega-3 fatty acids (ω-3) play an anti-inflammatory role and they are reported to decrease hepatic injury in Thioacetamide (TAA) fibrotic model. We investigated the effects of GL and ω-3 on liver inflammation and fibrosis in rats and clarified the effects of these natural compounds on NF-κB level. 50 male Wistar rats randomized to 5 groups: Control group and 4 groups received TAA 200 mg/kg i.p. twice weekly for 8 weeks: TAA group, GL group (received GL 25 mg/kg daily by oral tube), ω-3 group (received ω-3150 mg/kg daily by oral tube), (GL + ω-3) group (received similar combined doses of both natural compounds). GL and ω-3 alone or in combination protected the liver from TAA hepatotoxic effects as they significantly decreased serum AST activity and serum total bilirubin level, they also significantly increased serum albumin and total protein levels. The hepatoprotective effects of GL and ω-3 were confirmed by the histopathological analysis as they significantly reduced the necroinflammatory scores and the extent of fibrosis. GL and ω-3 significantly decreased liver malondialdehyde level (P < 0.005), liver NF-ƙB level (P < 0.005) and its tissue expression as detected by immunohistochemistry. In conclusion, glycyrrhizin and omega-3 fatty acids alone or in combination have potent anti-inflammatory, anti-oxidant and anti-fibrotic effects.

Evaluation of Serum Levels of HER2, MMP-9, Nitric Oxide, and Total Antioxidant Capacity in Egyptian Breast Cancer Patients: Correlation with Clinico-Pathological Parameters

Breast cancer is by far the most common cancer in women worldwide and the main cause of cancer-related mortality. Breast cancer accounts for 38% of all malignancies among Egyptian women. The aim of our study was to evaluate the serum levels of human epidermal growth factor receptor-2 (HER2), matrix metalloproteinase-9 (MMP-9), nitric oxide (NO), and total antioxidant capacity (TAC) in breast cancer patients and to correlate these markers with clinico-pathological parameters. Serum HER2, MMP-9, and carcinoma antigen 15-3 (CA 15-3) were assessed in 80 breast cancer patients and ten healthy subjects as a control group by the enzyme-linked immunosorbent assay (ELISA) technique while NO and TAC were assessed by a colorimetric method. Serum HER2 was ≥15 ng/mL in nine patients (11.3%). High HER2 ECD levels were significantly associated with tissue HER2 (P<0.0001), metastasis (P= 0.0024), and negativity of both estrogen (P=0.0075) and progesterone (P=0.0239) receptors. Serum MMP-9 (P=0.0013), NO (P<0.0001), and CA 15-3 (P<0.0001) were significantly increased while serum TAC was significantly (P=0.01) decreased in breast cancer patients as compared to the control group. Serum MMP-9 was increased significantly (P=0.028) in metastatic patients as compared to non-metastatic patients. We found a positive correlation between serum HER2 and CA 15-3 (r=36, p=0.005). In conclusion, serum HER2 reflects the tissue HER2 status of breast cancer, so the determination of serum HER2 is helpful in assessing HER2 status, but in addition, a high level may reflect metastatic disease. Also, serum MMP-9 can be useful for denoting the development of metastasis in breast cancer patients. Follow-up is needed to evaluate the value of serum HER2 and MMP-9 as prognostic markers.

Naringin attenuates thioacetamide-induced liver fibrosis in rats through modulation of the PI3K/Akt pathway

Aims: Naringin (NR) is a flavanone glycoside extracted from grapefruits and citrus fruits. The aim of this study is to investigate the antifibrotic efficacy of NR in thioacetamide (TAA)‐induced hepatic fibrosis in rats through evaluating NR effect on the PI3K/Akt pathway. Main methods: Hepatic fibrosis was induced in rats by intraperitoneal injection of TAA (200 mg/kg) twice per week for 6 weeks. Simultaneously, NR (40 mg/kg/day, p.o.) was given along with TAA injection. The ratio of P‐Akt/Akt was assessed in hepatic homogenate as well as antioxidant enzymes (catalase, superoxide dismutase (SOD), glutathione peroxidase (GPx)) and lipid peroxidation marker, malondialdehyde (MDA). Serum level of interleukin (IL)‐6 were measured using ELISA. Hepatic tissues were examined histopathologically using hematoxylin and eosin (H&E) and Masson trichome staining. Tissue expression of alpha smooth muscle actin (&agr;‐SMA), transforming growth factor &bgr;1 (TGF‐&bgr;1), caspase‐3 and fibronectin were scored immunohistochemically. Finally, the mRNA level of cytokine genes (IL‐1&bgr;, IL‐6, IL‐10, interferon gamma (IFN‐&ggr;)), caspase‐3, TGF‐&bgr;1 and fibronectin were quantified using qPCR. Key findings: NR significantly suppressed Akt phosphorylation associated with increased number of caspase‐3 positive cells especially in the fibrotic areas. Liver tissues of treated rats showed restoration of normal liver histology and decrease in collagen and fibronectin deposition. Furthermore, NR treatment ameliorated oxidative stress and inflammatory cytokine production. Significance: NR alleviated experimental liver fibrosis through inhibition of PI3K/Akt pathway beside its anti‐inflammatory and antioxidant effects. Therefore, NR is a promising therapeutic candidate for hepatic fibrosis. Graphical abstract Figure. No caption available.

A newly developed silymarin nanoformulation as a potential antidiabetic agent in experimental diabetes

AIM This study aimed to develop a new stable nanoformulation of silymarin (SM) with optimum enhanced oral bioavailability and to evaluate its effect as well as mechanism of action as a superior antidiabetic agent over native SM using streptozotocin-induced diabetic rats. MATERIALS AND METHODS SM-loaded pluronic nanomicelles (SMnp) were prepared and fully characterized. Biochemical parameters were performed as well as histological, confocal and reverse-transcription polymerase chain reaction studies on pancreatic target tissues. RESULTS & CONCLUSION SMnp were found to improve significantly the antihyperglycemic, antioxidant and antihyperlipidemic properties as compared with native SM. In addition, SMnp was found to be a more efficient agent over SM in the management of diabetes and its associated complications due to its superior bioavailability in vivo, and the controlled release profile of SM. [Formula: see text].

Galectin-3 and matrix metalloproteinase-9: Perspective in management of hepatocellular carcinoma

Aim Hepatocellular carcinoma (HCC) is the fifth most common cancer in men and the seventh in women. HCC varies widely in incidence through the world, with rising incidence in Egypt. This study aimed to estimate the serum levels of matrix metalloproteinase-9 (MMP-9) and its substrate galectin-3 in order to evaluate their diagnostic accuracy and their relation to HCC-related clinical features. Methods For this purpose, serum levels of these biochemical markers were assessed in 50 HCC patients, 30 cirrhotic patients in addition to 10 healthy subjects as a control group using enzyme linked immune-sorbent assay (ELISA). Results In the present study, circulating level of galectin-3, MMP-9 increased significantly in HCC as compared to the control group (P = 0.044 and 0.04, respectively). However, no significant difference was observed between cirrhotic and HCC patients (P = 0.231 and 0.193, respectively). Our study found that HCC patients with metastatic spread had a significant elevation of both serum galectin-3 and MMP-9 levels (P = 0.028 and <0.0001, respectively). In addition, galectin-3 level significantly increased in HCC patients with poor prognosis suffering from portal vein invasion (P = 0.014). Moreover, MMP-9 increased significantly with increasing stage of Barcelona-Clinic Liver Cancer Group diagnostic and treatment strategy (P = 0.01). Conclusion MMP-9 and galectin-3 could be used as a guide for prognosis of HCC since they may play a role in HCC progression and metastasis. However, they are not useful markers for HCC diagnosis.

Nitric Oxide is a Potential Diagnostic Marker for Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is the fifth most common cancer in men and the seventh most common in women. This cancer varies widely in incidence throughout the world, with rising incidence in Egypt. HCC is considered the second most frequent cause of cancer incidence and mortality among men in Egypt. This study aimed to estimate the serum levels of nitric oxide (NO) and glutathione reductase in order to evaluate their role as oxidative status markers in HCC development and progression. For this purpose, serum levels of these parameters were assessed in 50 HCC patients, and 30 cirrhotic patients in addition to 15 healthy subjects as a control group. In the present study, glutathione reductase activity showed a significant increase in HCC as compared to the control group (P= 0.019). On the other hand, no significant difference was observed between the cirrhotic and HCC patients (P= 0.492). Serum NO was significantly higher in patients with HCC than in cirrhotic patients (P= 0.001) or the control group (P= 0.001), with a sensitivity of (74%) and specificity of (88.89%) at a cut-off level of 614.1 μmol/l. While AFP, alpha-fetoprotein, at a cutoff level of 200 ng/ml had a sensitivity of (52%), the specificity was (100%). Indeed, nitric oxide was high in 62.5% of AFP-negative HCC patients. In conclusion, glutathione reductase has no role in HCC diagnosis. However, nitric oxide is a potential diagnostic marker for HCC. The simultaneous determination of serum nitric oxide and AFP gave significant improvement in the detection of HCC patients compared to that of AFP alone.