Protective effect of pregabalin on renal and renal endothelial damage in sepsis induced by lipopolysaccharide.

OBJECTIVE: We investigated the protective effects of pregabalin (PRG) on kidney and renal endothelial damage in sepsis induced by Lipopolysaccharide (LPS). MATERIALS AND METHODS: Rats were randomly divided into three groups as control, LPS and LPS+PRG. Saline solution was administered 30 mg/kg orally and 5 mg/kg intraperitoneally (i.p.) to the control group. LPS was applied as 5 mg/kg, i.p. to the LPS group. In the LPS+PRG group, PRG at 30 mg/kg orally and one hour before LPS administration, one hour later 5 mg/kg i.p. LPS was applied. Rats were sacrificed 6 hours after LPS administration. RESULTS: White Blood Cell (WBC), granulocyte, Blood Urea Nitrogen (BUN), creatinine, uric asid, Total Oxidant Status (TOS) and Oxidative Stress Index (OSI) significantly increased (p<0.05); platelets (PLT), activated partial thromboplastin time (aPTT) and Total Antioxidant Status (TAS) significantly decreased in the LPS group compared to the control group (p<0.05). In the LPS+PRG group WBC, granulocyte, BUN, creatinine, uric asid, TOS and OSI significantly decreased (p<0.05); PLT, aPTT and TAS significantly increased compared to the LPS group(p<0.05). Histopathological examinations showed that kidney and renal endothelial damage in the LPS group decreased in the LPS+PRG group. Immunohistochemically IL1-ß, IL-6, IL-10, TNF-α expressions in kidney tissue and Toll-Like Receptors-4 (TLR-4) and NF-κB expressions in the renal endothelial tissue significantly increased in the LPS group compared to the control group and significantly decreased in the LPS+PRG group compared to the LPS group (p<0.001). CONCLUSIONS: Sepsis causes kidney and renal endothelial damage and PRG reduces this damage. Therefore PRG can be used in prophylactic treatment in sepsis, supported by more studies.

In this study, kidney and renal endothelial damage in sepsis was investigated. The effect of pregabalin on kidney and renal endothelial damage in sepsis was evaluated.

Identification of differentially expressed miRNAs and mRNAs associated with the regulation of breast cancer via in silico and in vitro methods.

miRNA expressions are altered during development of breast cancer (BC). The aim of this study is to identify novel cancer-related miRNAs and pathways to understand the mechanisms of BC subtypes. GSE59247 dataset was downloaded from gene expression omnibus (GEO) database and analyzed with GEO2R software. The differential miRNA expressions in BC cells were evaluated by miRNome PCR array. Venn diagram was used to reveal co-differentially expressed miRNAs between GSE59247 dataset and miRNome array. Clinical prognostic significance of selected miRNAs was evaluated via Kaplan Meier curve. KEGG pathway enrichment analysis was performed to find miRNA targets and results were validated by TNM plot analysis and q-RT-PCR. TargetScan database was used to predict the association of miRNAs and 3'-untranslated regions of target genes and their expressions were visualized by human protein atlas database. Venn diagram analysis showed overlap of 11 miRNAs from in silico and in vitro analysis. KEGG analysis revealed 'Lysine Degradation Pathway' as the most significantly enriched targeted pathway. q-RT-PCR results confirmed that Lysine degradation pathway related genes SETD7, SETDB2, EHHADH, SETMAR, KMT2A and SUV39H2 were differentially expressed in BC cells. Target prediction analysis identified binding sites between miR-1323-5p and 3'-UTR of SETD7, miR-129-5p and 3'-UTR of EHHADH and miR-628-5p and 3'-UTR of SETDB2 mRNA. Notably, miR-1323-5p, miR-129-5p, and miR-628-5p are differentially expressed in BC and they bind to 3'UTR of critical genes of Lysine degradation pathway, namely SETD7, SETDB2 and EHHADH. These miRNAs might serve as potential diagnostic and prognostic biomarkers for progression.

Expression patterns of miR-34a, miR-125b, miR-221 and antioxidant gene NRF2 in plasma samples of patients with atherosclerosis.

Atherosclerosis is one of the main reasons of cardiovascular diseases, the most common cause of death in the world. NRF2 is a critical transcriptional factor that regulates oxidative stress response and contributes to the pathogenesis of atherosclerosis. This study aims to compare the expression levels of miR-34a, miR-125b, miR- 221 and NRF2 in blood samples of patients with atherosclerosis and of controls to find a novel link between microRNAs, oxidative stress and atherosclerosis. miR-34a, miR-125b, miR-221 and NRF2 relative expressions were analysed in 26 atherosclerosis patients and 25 healthy controls by q-RT-PCR assay. The receiver operating characteristic curve (ROC) was used to assess the diagnostic values of miR-34a, miR-125b, miR-221 and NRF2 by comparing the area under the curves (AUC) to differentiate between atherosclerosis and control samples. miR-34a and NRF2 were significantly upregulated, whereas miR-125b and miR-221 were significantly downregulated in patients compared with healthy controls. The ROC curves suggested high diagnostic value of miR-221 (AUC: 0.7477), miR-125b (AUC: 0.8523) and NRF2 (AUC: 0.838) for detection of atherosclerosis. Our results suggest that circulating miR-34a, miR-125b and miR-221 levels can be used as novel biomarkers for detection of atherosclerosis by targeting NRF2.

Identification of miR-17, miR-21, miR-27a, miR-106b and miR-222 as endoplasmic reticulum stress-related potential biomarkers in circulation of patients with atherosclerosis.

Atherosclerosis and related cardiovascular diseases are among the most common causes of death worldwide. Unfolded protein response, also known as Endoplasmic reticulum stress, has a critical role in many diseases including atherosclerosis. Small non-coding microRNAs (miRNA), which generally suppress gene expression, regulate UPR signalling and they may also be involved in the progression of atherosclerosis. We aim to investigate the expression levels of miR-17, miR-21, miR-27a, miR-106b, miR-222 and CHOP gene in circulation of atherosclerosis patients compared to healthy controls to establish a link between ER stress and atherosclerosis. miRNA containing whole RNA was isolated from blood samples of 25 patients with atherosclerosis and 26 healthy controls. Expression levels of miRNAs and CHOP were measured via Real Time PCR method. miR-17 and miR-106b were significantly increased while miR-21, miR-27a, and miR-222 were significantly decreased in patients compared to controls. CHOP gene was also dramatically and significantly induced in patient samples. miR-17, miR-21, miR-27a, miR-106b, miR-222 and CHOP were significantly differentially expressed in patients with atherosclerosis. Each miRNA and CHOP might regulate atherosclerotic plaque progression and they can be used as a biomarker in the diagnosis and follow-up of atherosclerosis-related cardiovascular diseases.

Therapeutic Targeting of the NRF2 Signaling Pathway in Cancer.

Cancer is one of the most fatal diseases with an increasing incidence and mortality all over the world. Thus, there is an urgent need for novel therapies targeting major cancer-related pathways. Nuclear factor-erythroid 2-related factor 2 (NRF2) and its major negative modulator Kelch-like ECH-associated protein 1 (KEAP1) are main players of the cellular defense mechanisms against internal and external cell stressors. However, NRF2/KEAP1 signaling pathway is dysregulated in various cancers, thus promoting tumor cell survival and metastasis. In the present review, we discuss the mechanisms of normal and deregulated NRF2 signaling pathway focusing on its cancer-related functions. We further explore activators and inhibitors of this pathway as cancer targeting drug candidates in order to provide an extensive background on the subject.

Potential Applications of NRF2 Modulators in Cancer Therapy.

The nuclear factor erythroid 2-related factor 2 (NRF2)-Kelch-like ECH-associated protein 1 (KEAP1) regulatory pathway plays an essential role in protecting cells and tissues from oxidative, electrophilic, and xenobiotic stress. By controlling the transactivation of over 500 cytoprotective genes, the NRF2 transcription factor has been implicated in the physiopathology of several human diseases, including cancer. In this respect, accumulating evidence indicates that NRF2 can act as a double-edged sword, being able to mediate tumor suppressive or pro-oncogenic functions, depending on the specific biological context of its activation. Thus, a better understanding of the mechanisms that control NRF2 functions and the most appropriate context of its activation is a prerequisite for the development of effective therapeutic strategies based on NRF2 modulation. In line of principle, the controlled activation of NRF2 might reduce the risk of cancer initiation and development in normal cells by scavenging reactive-oxygen species (ROS) and by preventing genomic instability through decreased DNA damage. In contrast however, already transformed cells with constitutive or prolonged activation of NRF2 signaling might represent a major clinical hurdle and exhibit an aggressive phenotype characterized by therapy resistance and unfavorable prognosis, requiring the use of NRF2 inhibitors. In this review, we will focus on the dual roles of the NRF2-KEAP1 pathway in cancer promotion and inhibition, describing the mechanisms of its activation and potential therapeutic strategies based on the use of context-specific modulation of NRF2.

Common telomerase reverse transcriptase promoter mutations in hepatocellular carcinomas from different geographical locations.

AIM: To determine the mutation status of human telomerase reverse transcriptase gene (TERT) promoter region in hepatocellular carcinoma (HCC) from different geographical regions. METHODS: We analyzed the genomic DNA sequences of 59 HCC samples comprising 15 cell lines and 44 primary tumors, collected from patients living in Asia, Europe and Africa. We amplified a 474 bp DNA fragment of the promoter region of TERT gene including the 1295228 and 1295250 sequence of chromosome 5 by using PCR. Amplicons were then sequenced by Sanger technique and the sequence data were analyzed with by using DNADynamo software in comparison with wild type TERT gene sequence as a reference. RESULTS: The TERT mutations were found highly frequent in HCC. Eight of the fifteen tested cell lines displayed C228T mutation, and one had C250T mutation with a mutation frequency up to 60%. All of the mutations were heterozygous and mutually exclusive. Ten out of forty-four tumors displayed C228T mutation, and additional five tumors had C250T mutation providing evidence for mutation frequency of 34% in primary tumors. Considering the geographic origins of HCC tumors tested, TERT promoter mutation frequencies were higher in African (53%), when compared to non-African (24%) tumors (P = 0.056). There was also a weak inverse correlation between TERT promoter mutations and murine double minute 2 single nucleotide polymorphism 309 TG polymorphism (P = 0.058). Mutation frequency was nearly two times higher in established HCC cell lines (60%) compared to the primary tumors (34%). CONCLUSION: TERT promoter is one of most frequent mutational targets in liver cancer, and hepatocellular carcinogenesis is highly associated with the loss of telomere-dependent cellular senescence control.

Genetics and epigenetics of liver cancer.

Hepatocellular carcinoma (HCC) represents a major form of primary liver cancer in adults. Chronic infections with hepatitis B (HBV) and C (HCV) viruses and alcohol abuse are the major factors leading to HCC. This deadly cancer affects more than 500,000 people worldwide and it is quite resistant to conventional chemo- and radiotherapy. Genetic and epigenetic studies on HCC may help to understand better its mechanisms and provide new tools for early diagnosis and therapy. Recent literature on whole genome analysis of HCC indicated a high number of mutated genes in addition to well-known genes such as TP53, CTNNB1, AXIN1 and CDKN2A, but their frequencies are much lower. Apart from CTNNB1 mutations, most of the other mutations appear to result in loss-of-function. Thus, HCC-associated mutations cannot be easily targeted for therapy. Epigenetic aberrations that appear to occur quite frequently may serve as new targets. Global DNA hypomethylation, promoter methylation, aberrant expression of non-coding RNAs and dysregulated expression of other epigenetic regulatory genes such as EZH2 are the best-known epigenetic abnormalities. Future research in this direction may help to identify novel biomarkers and therapeutic targets for HCC.