Pentoxifylline and its association with kaempferol improve NASH-associated manifestation in mice through anti-apoptotic, anti-necroptotic, antioxidant, and anti-inflammatory mechanisms.

OBJECTIVE: Non-alcoholic fatty liver disorders (NAFLD), particularly non-alcoholic steatohepatitis (NASH), have emerged as a leading cause of liver transplantation and mortality. However, the pathophysiology of NASH remains unknown. Oxidative stress, apoptosis, and necroptosis pathways are heavily linked to NASH. Therefore, the current study aimed to investigate the underlying mechanism for Pentoxifylline's (PTX) activity in NASH management, either alone or in combination with Kaempferol (KP). MATERIALS AND METHODS: A total of 32 male C57BL/6J mice were divided into four groups: the mice in the control group were fed a standard chow diet and given a vehicle; the mice in NASH group were maintained on NASH protocol for 25 days; the mice in the PTX group were kept on NASH protocol for 25 days and given PTX (100 mg/kg), and PTX+KP mice group were given NASH protocol along with KP (50 mg/kg) and PTX (100 mg/kg) simultaneously. RESULTS: The LDL-C, total cholesterol, triglycerides, glutathione peroxidase (GPx), superoxide dismutase (SOD), malondialdehyde (MDA), glucose, insulin, and HOMA-IR levels were considerably decreased in the PTX and PTX+KP treated groups. AMP-activated protein kinase (AMPK) Gene expression of the liver was significantly increased in the other treated groups, but peroxisome proliferator-activated receptor (PPAR), phosphorylated mixed lineage kinase-like protein (pMLKL), and sterol regulatory element binding protein 1 (SREBP1) were reduced significantly. Caspase-8 and receptor-interacting serine/threonine protein kinase (RIPK3) protein expression were significantly decreased in the PTX and PTX+KP groups compared to NASH group and nuclear factor kappa B (NF-κB), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) immunohistochemistry expression. CONCLUSIONS: Our current study suggests that PTX and its combination with KP have a significant ameliorative effect against NASH via novel mechanisms involving the regulation of apoptosis and necroptosis, as well as decreased oxidative stress, lipogenesis, proinflammatory cytokines, and modulation of histopathological manifestation.

Association of MicroRNA-146a rs2910164 Gene Polymorphism with Metabolic Syndrome.

Alteration in microRNA-146a (miRNA-146a) expression is an important event in the pathogenesis of many human diseases. MiRNA-146a rs2910164 is a functional polymorphism that showed association with several diseases. Metabolic syndrome is an aggregation of multiple risk factors including impaired glucose tolerance, increased highdensity lipoprotein, abdominal obesity, and high blood pressure. The aim of this study was to assess the relation of miRNA-146a rs2910164 with metabolic syndrome and its component traits in Egyptian women from the Suez Canal area. The study included 100 healthy female subjects and 100 metabolic syndrome patients. The component traits of metabolic syndrome were determined and the genotypes of the polymorphisms were assessed using the polymerase chain reaction-restriction fragment length polymorphism technique using the restriction enzyme Hpy188I. The rare C allele had a significantly higher frequency in metabolic syndrome patients (P = 0.013). The heterozygote GC and the rare CC genotypes showed a significant increase in body mass index, waist circumference, triglycerides, total cholesterol, low-density lipoprotein, systolic and diastolic blood pressure. The GC genotype was associated with higher fasting blood glucose, fasting serum insulin and insulin resistance. The carriers of CC genotype had significantly lower HDL compared with the GG genotype carriers. In conclusion, The C allele of miRNA-146a rs2910164 showed positive association with increased susceptibility to metabolic syndrome and its phenotypes in the study population.

Association of catalase gene polymorphisms with catalase activity and susceptibility to systemic lupus erythematosus in the Suez Canal area, Egypt.

The present study evaluated the relationship of genetic variants in both promoter (-262 C/T) and in exonic (389 C/T) regions of the catalase (CAT) gene to CAT activity and risk of systemic lupus erythematosus (SLE) in Suez Canal-area patients. CAT gene polymorphisms were assessed by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). CAT activity was measured by using a spectrophotometer. We compared the frequencies of CAT 389 C/T and -262 C/T polymorphic variants between SLE patients (n = 103) and healthy controls (n = 103). CAT 389 C/T is associated with SLE susceptibility, with the T allele being significantly more frequent among SLE patients than healthy controls. There was no association, however, between CAT activity and genotypes of 389 C/T. We did not observe significant differences in the prevalence of CAT -262 C/T polymorphic variants in SLE patients and controls, however, we found that patients with the CAT -262 CT and TT genotypes had low CAT activity, and these genotypes showed a significant association with thrombocytopaenia, leukopaenia and the presence of anti-snRNP in SLE patients. In conclusion, the present study supports the notion of in vivo oxidative stress in SLE as indicated by the decrease in CAT activity. The allelic variations in the CAT gene -262 are more likely to affect the expression or the function of the enzyme. Since CAT may be pathogenetically linked to SLE, and owing to its free-radical origin, it appears reasonable to target lipid peroxidation by dietary and/or pharmacological antioxidants.

Influence of glutathione S-transferase polymorphisms on type-2 diabetes mellitus risk.

Glutathione S-transferase (GST) protects cells against oxidative stress. We evaluated the effect of genetic polymorphisms of the GST gene family on the risk of developing type-2 diabetes mellitus and on glycemic control. We also investigated the effects of smoking combined with these polymorphisms on type-2 diabetes mellitus risk. We enrolled 100 type-2 diabetes mellitus patients and 100 healthy controls matched for age, gender and origin, from the Sinai area of Egypt. Fasting serum glucose, HbA(1c) and lipid profiles were determined. Two polymorphisms were identified by multiplex PCR within the GST genes: GSTM1 and GSTT1. The proportion of the GSTT1- and GSTM1-null genotypes was significantly greater in diabetic patients when compared to controls. Patients carrying both null polymorphisms had a 3.17-fold increased risk of having type-2 diabetes mellitus compared to those with normal genotypes of these two genes (P = 0.009). Additionally, patients with the GSTT1-null genotype had higher levels of triglycerides and very low-density lipoprotein cholesterol compared to those with the GSTT1-present genotype. On the other hand, patients with the GSTM1- null genotype had significantly higher levels of HbA(1c) and significantly higher diastolic blood pressure compared to those with the GSTM1- present genotype. The interaction between these genotypes and smoking status was not significant. These results give evidence that the GSTT1- and GSTM1-null genotypes, alone or combined, are associated with increased risk of type-2 diabetes mellitus, regardless of smoking status. Only the GSTM1-null genotype had an effect on glycemic control.

Heme oxygenase-1 transduction in endothelial cells causes downregulation of monocyte chemoattractant protein-1 and of genes involved in inflammation and growth.

Heme oxygenase (HO-1) has been implicated as an anti-inflammatory gene. HO-1 overexpression, transiently and chronically, affects heme protein expression, attenuates TNF-mediated cell death, and decreases adhesion molecules. We assessed the effect of oxidant-mediated agents such as glucose and heme on 8-epi-isoprostane PGF2alpha (8-epi-PGF2alpha) and monocyte chemoattractant protein-1 (MCP-1). Glucose and heme increased both 8-epi-PGF2alpha and MCP-1. Overexpression of HO-1 decreased both 8-epi-PGF2alpha and MCP-1. To identify target genes involved in HO-1-mediated regulation of inflammation, a serial analysis of gene expression mRNA profile was performed in endothelial cells (EC) overexpressing the human HO-1 gene by transduction of a retrovirus carrying the HO-1 gene. Gene arrays (differential displays among 2400 genes) were used to identify known and novel differentially expressed genes. The levels of expression for several genes were confirmed by real time PCR in cells overexpressing the HO-1 gene. In HO-1 overexpressing cells, VEGF and the prostaglandin transporter were greatly increased while MCP-1 levels were decreased by 2.5-fold. The data from this study are relevant to understanding the mechanisms underlying the pathophysiological effects of HO-1 deficiency on endothelial cell injury and inflammation.