Mahmoud Senousy

AIM: Alcohol abuse is a significant causative factor of death worldwide. The Notch1 signaling pathway is involved in alcohol tolerance, withdrawal and dependence. Agomelatine is a known antidepressant acting as a melatonin receptor (MT1/2) agonist and a 5-hydroxytryptamine receptor-2C antagonist. However, its effects on alcohol cravings and alcohol withdrawal symptoms have not been investigated. In this study, we assessed the possibility of using agomelatine for the treatment of these symptoms in a rat model of alcoholism and the possible role of Notch1 signaling.

MAIN METHODS: We induced alcoholism in rats using a free-choice drinking model for 60 days. From day 61, free-choice was continued until day 82 for the craving model, whereas only water was offered in the withdrawal model. Meanwhile, the treated groups for both models received agomelatine (50 mg/kg/day) orally from day 61 to 82, followed by behavioral, histopathological and biochemical assessment.

KEY FINDINGS: Agomelatine treatment caused significant decrease in alcohol consumption with a positive effect on anxiety-like behavior in the open field, memory in the Morris water maze and immobility in the forced swim test. Moreover, agomelatine induced the expression of Notch1 pathway markers, including Notch1, NICD, CREB, CCNE-2, Hes-1, both total and phosphorylated ERK1/2, MMP9, Per2and RGS-2 in the hippocampal formation. By contrast, NMDAR expression was reduced. Furthermore, agomelatine normalized the serum levels of BDNF, cortisol, dopamine and glutamate which were disrupted by alcohol consumption.

SIGNIFICANCE: Based on these findings, agomelatine reversed alcohol cravings and withdrawal symptoms associated with alcohol dependence by modulating the Notch1 signaling pathway.

The influence of and variants on colorectal cancer (CRC) susceptibility and their impact on //epithelial-mesenchymal transition (EMT) and //EMT axes in CRC are unknown. We investigated the influence of and on the risk of CRC and adenomatous polyps (AP), their impact on the long noncoding RNAs and expression and their target , /E-cadherin pathways, along with their potential as early CRC biomarkers. Overall, 280 individuals were recruited: 140 patients with CRC, 40 patients with AP, and 100 healthy volunteers. Genotyping and serum expression profiles were assessed using qPCR. The EMT biomarker, E-cadherin, was measured by ELISA. was associated with increased CRC risk, whereas was protective. Serum and were upregulated in CRC and AP patients versus healthy controls, whereas, , and E-cadherin were downregulated in CRC versus non-CRC groups. showed superior diagnostic potential for CRC and predicted CRC risk among non-CRC groups in the multivariate logistic analysis. , , and levels were correlated with E-cadherin, tumor stage, lymph node and distant metastasis. E-cadherin was lost in metastatic vs. non-metastatic CRC. genotype carriers showed higher E-cadherin levels than carriers. was correlated with lymph node status. For the first time, and are potential genetic CRC predisposition markers, with possibly impacting the EMT process. Serum , , and are novel non-invasive diagnostic biomarkers that could improve the clinical outcome of CRC.

The reliable identification of diffuse large B-cell lymphoma (DLBCL)-specific targets owns huge implications for its diagnosis and treatment. Long non-coding RNAs (lncRNAs) are implicated in DLBCL pathogenesis; however, circulating DLBCL-related lncRNAs are barely investigated. We investigated plasma lncRNAs; HOTAIR, Linc-p21, GAS5 and XIST as biomarkers for DLBCL diagnosis and responsiveness to R-CHOP therapy. Eighty-four DLBCL patients and thirty-three healthy controls were included. Only plasma HOTAIR, XIST and GAS5 were differentially expressed in DLBCL patients compared to controls. Pretreatment plasma HOTAIR was higher, whereas GAS5 was lower in non-responders than responders to R-CHOP. Plasma GAS5 demonstrated superior diagnostic accuracy (AUC = 0.97) whereas a panel of HOTAIR + GAS5 superiorly discriminated responders from non-responders by ROC analysis. In multivariate analysis, HOTAIR was an independent predictor of non-response. Among patients, plasma HOTAIR, Linc-p21 and XIST were correlated. Plasma GAS5 negatively correlated with International Prognostic Index, whereas HOTAIR positively correlated with performance status, denoting their prognostic potential. We constructed the lncRNAs-related protein-protein interaction networks linked to drug response via bioinformatics analysis. In conclusion, we introduce plasma HOTAIR, GAS5 and XIST as potential non-invasive diagnostic tools for DLBCL, and pretreatment HOTAIR and GAS5 as candidates for evaluating therapy response, with HOTAIR as a predictor of R-CHOP failure. We provide novel surrogates for future predictive studies in personalized medicine.

AIMS: Dipeptidyl peptidase-4 (DPP-4) has been involved in the pathogenesis of inflammatory bowel diseases (IBD), yet the underlying mechanisms remain inconclusive. The present study aimed to investigate the potential of linagliptin, a potent/selective DPP-4 inhibitor with marked anti-inflammatory actions, to attenuate trinitrobenzene sulfonic acid (TNBS)-evoked colitis in rats; an experimental model of IBD, and the implicated molecular mechanisms. This may add to the clinical utility of linagliptin for the management of patients with coexisting IBD and diabetes mellitus. Notably, no former studies have linked JAK2/STAT3, HMGB1/NF-κB, and Nrf2/HO-1 signaling in TNBS-evoked colitis.

MATERIALS AND METHODS: Western blotting and ELISA were used to determine the levels of target signals.

KEY FINDINGS: Administration of linagliptin (1.5 mg/kg; p.o.) mitigated the colitis severity via diminishing the disease activity index, colon weight/length ratio, and macroscopic scores. Linagliptin also lowered the colonic histologic scores and leukocyte invasion. Notably, linagliptin inhibited the colonic DPP-4 activity and upregulated the expression of intestinotrophic GLP-2 without incurring hypoglycemia in animals. Linagliptin curbed inflammation through the suppression of colonic IL-6, TNF-α, and myeloperoxidase and upregulation of IL-10. It also inhibited the IL-6/JAK2/STAT3 pathway via downregulating p-JAK2/JAK2 and p-STAT3/STAT3 protein expression and HMGB1/RAGE/NF-κB cascade through lowering HMGB1, RAGE, and p-NF-κB p65/NF-κB p65 protein expression. In the context of mucosal oxidative stress, linagliptin diminished lipid peroxides and augmented GSH, GPx, and total antioxidant capacity. It also activated Nrf2/HO-1 pathway via upregulating Nrf2 and HO-1 protein expression.

SIGNIFICANCE: Linagliptin shows a promise for the management of IBD via targeting IL-6/JAK2/STAT3, HMGB1/RAGE/NF-κB, and Nrf2/HO-1 pathways.

AIMS: Dipeptidyl peptidase-4 (DPP-4) has been involved in the pathogenesis of inflammatory bowel diseases (IBD), yet the underlying mechanisms remain inconclusive. The present study aimed to investigate the potential of linagliptin, a potent/selective DPP-4 inhibitor with marked anti-inflammatory actions, to attenuate trinitrobenzene sulfonic acid (TNBS)-evoked colitis in rats; an experimental model of IBD, and the implicated molecular mechanisms. This may add to the clinical utility of linagliptin for the management of patients with coexisting IBD and diabetes mellitus. Notably, no former studies have linked JAK2/STAT3, HMGB1/NF-κB, and Nrf2/HO-1 signaling in TNBS-evoked colitis.

MATERIALS AND METHODS: Western blotting and ELISA were used to determine the levels of target signals.

KEY FINDINGS: Administration of linagliptin (1.5 mg/kg; p.o.) mitigated the colitis severity via diminishing the disease activity index, colon weight/length ratio, and macroscopic scores. Linagliptin also lowered the colonic histologic scores and leukocyte invasion. Notably, linagliptin inhibited the colonic DPP-4 activity and upregulated the expression of intestinotrophic GLP-2 without incurring hypoglycemia in animals. Linagliptin curbed inflammation through the suppression of colonic IL-6, TNF-α, and myeloperoxidase and upregulation of IL-10. It also inhibited the IL-6/JAK2/STAT3 pathway via downregulating p-JAK2/JAK2 and p-STAT3/STAT3 protein expression and HMGB1/RAGE/NF-κB cascade through lowering HMGB1, RAGE, and p-NF-κB p65/NF-κB p65 protein expression. In the context of mucosal oxidative stress, linagliptin diminished lipid peroxides and augmented GSH, GPx, and total antioxidant capacity. It also activated Nrf2/HO-1 pathway via upregulating Nrf2 and HO-1 protein expression.

SIGNIFICANCE: Linagliptin shows a promise for the management of IBD via targeting IL-6/JAK2/STAT3, HMGB1/RAGE/NF-κB, and Nrf2/HO-1 pathways.

Recently, oxidative stress was implicated in the environmental contaminant Di-(2-ethylhexyl) phthalate (DEHP)-induced testicular toxicity, however the mechanism is unclear. We investigated the role of oxidative stress-responsive microRNAs in DEHP-induced aberrations and the protective effect of the citrus flavonoid, hesperidin (HSP). Male Wistar rats were randomly allocated into four groups as vehicle-treated control, DEHP-alone group (500 mg/kg/day) for 30 days, and HSP (25 or 50 mg/kg) for 60 days; testicular damage was triggered by oral administration of DEHP (500 mg/kg/day) after thirty days of oral administration of HSP (25 or 50 mg/kg). DEHP administration reduced testis weight coefficient, serum testosterone, testicular 3β-hydroxysteroid dehydrogenase and antioxidant enzyme activities, and elevated serum fatty acid-binding protein-9, testicular malondialdehyde, and Bax/Bcl2 ratio. Aberrant testicular miR-126-3p and miR-181a expression was observed, along with decreased expression of sirtuin1 (SIRT1) and its targets; nuclear factor-erythroid 2-related factor2, haeme oxygenase-1, and superoxide dismutase2. HSP administration significantly ameliorated these changes and restored testicular function in a dose-dependent manner. We highlight a novel role of oxidative stress-miR-126/miR-181a-SIRT1 network in mediating DEHP-induced changes which were reversed by the antioxidant HSP.

Systemic sclerosis or systemic scleroderma (SSc) is an inflammatory autoimmune disease whose pathogenesis remains ambiguous; however, epigenetics, including long noncoding RNAs (lncRNAs) is an emerging paradigm. To date, the expression, role and clinical significance of most lncRNAs in SSc remain unelucidated. Herein, we investigated the plasma expression profiles of lncRNAs; ANCR, TINCR, HOTTIP, and SPRY4-IT1, which were linked to skin biology, in SSc patients and its subtypes, their potential as diagnostic tools and their correlations with autoantibodies and disease manifestations. Sixty-three SSc patients and thirty-five healthy volunteers were recruited. Autoantibody profile (anti-Scl-70, anti-centromere, anti-RNA polymeraseIII, anti-ribonucleoprotein, antinuclear, and anti-phospholipid antibodies) was determined. lncRNAs analysis was conducted using RT-qPCR. Plasma TINCR, HOTTIP, and SPRY4-IT1 upregulation and ANCR downregulation were observed in SSc patients compared with controls. SPRY4-IT1 was superior in SSc diagnosis in ROC analysis and predicted its risk in multivariate logistic analysis. Plasma SPRT4-IT1 was higher in diffuse than limited SSc. SPRY4-IT1 and HOTTIP were positively correlated with modified Rodnan skin score while ANCR showed a negative correlation only in limited SSc. ANCR and TINCR were positively correlated with disease duration and ESR, respectively. ANCR and SPRY4-IT1 were positively correlated with pulmonary hypertension. HOTTIP was positively correlated with antinuclear antibody. SPRY4-IT1 was positively correlated with HOTTIP in the whole group, and with TINCR only in diffuse SSc. We introduce plasma SPRY4-IT1, HOTTIP, ANCR and TINCR as novel candidate biomarkers for SSc, with SPRY4-IT1 could predict SSc diagnosis and discriminate its subtypes. Our findings widen the epigenetic landscape of SSc and provide surrogates for future predictive studies.

The pathogenesis of multiple sclerosis (MS) is influenced by the interaction of genetic and epigenetic mechanisms. The long noncoding RNA GAS5 acts as a competing endogenous RNA for microRNA-137 and is involved in demyelination. We investigated the association of GAS5 and miR-137 expression and their polymorphisms with MS susceptibility. One hundred and eight MS patients and 104 healthy controls were included. Expression analysis and genotyping of GAS5-rs2067079 and miR-137-rs1625579 single nucleotide polymorphisms were performed by qPCR. Serum GAS5 was upregulated, while serum miR-137 was downregulated in MS compared with the controls. Serum miR-137 was an excellent discriminator of MS patients from the controls (AUC = 0.97) and a negative independent predictor of MS in multivariate logistic analysis. Serum GAS5 expression was positively correlated with the expanded disability status scale scores in the relapsing-remitting MS patients. The rs2067079TT minor homozygote genotype was associated with an increased MS risk, while the rs1625579G minor allele was protective. rs1625579 showed an age-specific effect, while the rs2067079 affected the MS risk in gender- and age-specific manners. In MS patients, rs2067079TT was associated with a higher serum GAS5 than other genotypes, while serum miR-137 did not differ between rs1625579 genotypes. Our results suggest serum GAS5 and miR-137 as MS biomarkers, with miR-137 as a negative predictor of MS risk and GAS5 as a marker of MS severity. We propose rs2067079 and rs1625579 as novel genetic markers of MS susceptibility, and at least, rs2067079 possibly impacts the crosstalk between GAS5 and miR-137.

Single nucleotide polymorphisms (SNPs) in microRNA-target sites influence an individual's risk and prognosis for autoimmune diseases. Myotubularin-related protein 3 (MTMR3), an autophagy-related gene, is a direct target of miR-181a. We investigated whether MTMR3 SNP rs12537 in the miR-181a-binding site is associated with the susceptibility and progression of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Overall, 94 patients with RA, 80 patients with SLE, and 104 healthy volunteers were recruited. Genotyping and expression analysis of circulating MTMR3 and miR-181a were performed by qPCR. The autophagic marker MAP1LC3B was measured by ELISA. The rs12537 minor homozygote (TT) genotype was a candidate risk factor of both RA and SLE. rs12537TT was associated with lower serum MTMR3 expression and higher LC3B levels than other genotypes in patients with both diseases. Serum miR-181a expression was higher in rs12537TT carriers than in other genotypes among SLE patients. Serum miR-181a and MTMR3 levels were inversely correlated in SLE but not in RA patients. rs12537TT and serum miR-181a were positively associated with disease severity in both diseases. Our results identify a novel role of rs12537 in the susceptibility and progression of RA and SLE, possibly through impacting the interaction between miR-181a and MTMR3 leading to increased autophagy.

BACKGROUND: Genetic susceptibility for breast cancer (BC) is still poorly understood. A combination of multiple low-penetrant alleles of cancer-related genes and gene-gene interactions (epistasis) contributes to BC risk. Genetic variants in receptor activator of nuclear factor κB ligand (RANKL), osteoprotegerin (OPG), chitinase-3-like protein 1 (CHI3L1), and vitamin D receptor (VDR) genes are implicated in breast carcinogenesis; however, the influence of their epistatic effects on BC susceptibility has not yet been studied. We investigated the association of single nucleotide polymorphism (SNP)-SNP interactions and haplotypes of 6 SNPs in these 4 genes with the genetic predisposition of BC in Egyptian women.

PATIENTS AND METHODS: Data of 115 BC patients and 120 cancer-free controls were studied. Association tests were conducted using logistic regression models.

RESULTS: Individual SNPs showed weak statistical significance with BC susceptibility. The interactions between RANKL-rs9533156 and OPG-rs2073618; OPG-rs2073618 with CHI3L1-rs4950928, VDR-rs2228570 and VDR-rs1544410; OPG-rs2073617 and VDR-rs1544410; VDR-rs2228570 and VDR-rs1544410 were strongly associated with increased BC risk after adjustment for multiple comparisons. No SNPs were in strong linkage disequilibrium. The TCTCTG-rs9533156-rs2073618-rs2073617-rs4950928-rs2228570-rs1544410 haplotype was significantly associated with increased BC risk (adjusted odds ratio = 8.33; 95% confidence interval, 1.32-52.46; P = .025) compared with controls. TCCCTG haplotype stratified BC patients according to estrogen receptor/progesterone receptor status. TCTCTA was positively associated, and TCTCTG and TGTCTG haplotypes inversely correlated with bone metastasis. Bioinformatic analysis revealed 13 proteins commonly interacting with our 4 genes; the most significant was signal transducer and activator of transcription 5B.

CONCLUSION: Our results suggested that a stronger combined effect of SNPs in RANKL, OPG, CHI3L1, and VDR genes via gene-gene interaction may help predict BC risk and prognosis.

Reduced estradiol levels are associated with depression in women during the transition to and after menopause. A considerable number of studies focusing on the theme of treating depression through the activation of erythropoietin (EPO)-induced signaling pathways have been published. Venlafaxine is an approved antidepressant drug that inhibits both serotonin and norepinephrine transporters. The aim of the present study was to investigate the effects of venlafaxine on the depressive-like behaviors and serum estradiol levels in female rats following ovariectomy (OVX) and the possible roles of EPO-induced signaling pathways. Venlafaxine (10 mg/kg/day) was orally administered to OVX rats over a period of 4 weeks using two different treatment regimens: either starting 24 h or 2 weeks after OVX. Venlafaxine showed a superior efficacy in inducing antidepressant-like effects after an acute treatment (24 h post-OVX) than after the delayed treatment (2 weeks post-OVX) and was characterized by a decreased immobility time in the forced swimming test. In parallel, venlafaxine induced EPO and EPO receptor mRNA expression and increased levels of phospho-Janus kinase 2 (p-JAK2), phospho-signal transducer and activator of transcription 5, and phospho-extracellular signal-regulated kinase 1/2 in the hippocampus of OVX rats. Meanwhile, rats exhibited a marked reduction in the hippocampal Bax/Bcl2 ratio, caspase-3 activity, and tumor necrosis factor alpha levels after venlafaxine treatment. Venlafaxine also increased the hippocampal brain-derived neurotrophic factor and serum estradiol levels. Based on these findings, venlafaxine exerts a neuroprotective effect on OVX rats that is at least partially attributed to the activation of EPO/EPOR/JAK2 signaling pathways, anti-apoptotic activities, anti-inflammatory activities, and neurotrophic activities, as well as an increase in serum estradiol level. Graphical Abstract ᅟ.

Multiple sclerosis is a chronic inflammatory demyelinating central nervous system disorder leading to serious neurological deficits. Linagliptin, a dipeptidyl peptidase-4 inhibitor, recently showed neuroprotective properties against neurodegenerative diseases. This study investigated the possible neuroprotective effect of linagliptin against cuprizone-induced demyelination in mice and its potential early-remyelinating properties. C57Bl/6 mice were fed chow containing 0.7% cuprizone for 1 week, followed by 3 weeks of a 0.2% cuprizone diet. Linagliptin (10 mg/kg/day, p.o.) was given for 3 weeks starting from the second week. Linagliptin treatment improved behavioural and motor abnormalities induced by cuprizone, as demonstrated by open field, rotarod and grip strength tests. In parallel, linagliptin lessened the demyelination through enhancing Olig2 gene expression, as shown by increased myelin basic protein, myelin proteolipid protein levels and Luxol fast blue-staining intensity. Linagliptin attenuated cuprizone-induced oxidative stress by decreasing brain thiobarbituric acid reactive substances along with restoring reduced glutathione levels. Linagliptin exerted an anti-inflammatory effect by reducing brain tumor necrosis factor-alpha. Interestingly, linagliptin diminished phosphorylated JAK2, phosphorylated STAT3 and NF-κB p65 protein expression while up-regulating phosphorylated AMP-activated protein kinase (p-AMPK) protein and SIRT1 gene expression levels. In conclusion, linagliptin exerted a neuroprotective effect in mice with cuprizone-induced demyelination possibly by modulating AMPK/SIRT1 and JAK2/STAT3/NF-κB signalling pathways.