Background: The present study was conducted to evaluate the tumor suppressive effects of bone marrow derived mesenchymal stem cells (MSCs) in an experimental hepatocellular carcinoma (HCC) model in rats and to investigate the possible role of Wnt signaling in hepato-carcinogenesis.Methods: Ninety rats were included in the study and were divided equally into: Control group, rats which received MSCs only, rats which received MSCs vehicle only, HCC group induced by diethylnitroseamine (DENA) and CCl₄, rats which received MSCs after HCC induction, rats which received MSCs before HCC induction. Histopathological examination and gene expression of Wnt signaling target genes by real time, reverse transcription-polymerase chain reaction (RT-PCR) in rat liver tissue, in addition to serum levels of ALT, AST and alpha fetoprotein were performed in all groups.Results: Histopathological examination of liver tissue from animals which received DENA-CCl₄only, revealed the presence of anaplastic carcinoma cells and macro-regenerative nodules type II with foci of large and small cell dysplasia. Administration of MSCs into rats after induction of experimental HCC improved the histopathological picture which showed minimal liver cell damage, reversible changes, areas of cell drop out filled with stem cells. Gene expression in rat liver tissue demonstrated that MSCs downregulatedβ-catenin, proliferating cell nuclear antigen (PCNA),cyclin Dandsurvivingenes expression in liver tissues after HCC induction. Amelioration of the liver status after administration of MSCs has been inferred by the significant decrease of ALT, AST and Alpha fetoprotein serum levels. Administration of MSCs before HCC induction did not show any tumor suppressive or protective effect.Conclusions: Administration of MSCs in chemically induced HCC has tumor suppressive effects as evidenced by down regulation of Wnt signaling target genes concerned with antiapoptosis, mitogenesis, cell proliferation and cell cycle regulation, with subsequent amelioration of liver histopathological picture and liver function.

Diabetes mellitus type 1 is an autoimmune disorder caused by lymphocytic infiltration and beta cells destruction. Curcumin has been identified as a potent inducer of heme-oxygenase-1 (HO-1), a redoxsensitive inducible protein that provides protection against various forms of stress. A novel water soluble curcumin derivative (NCD) has been developed to overcome low in vivo bioavailability of curcumin. The aim of the present work is to evaluate the anti diabetic effects of the “NCD” and its effects on diabetes-induced ROS generation and lipid peroxidation in experimental type- 1 diabetes mellitus. We also examine whether the up regulation of HO-1 accompanied by increased HO activity mediates these antidiabetic and anti oxidant actions.

Curcumin exhibits anti-diabetic activities, induces heme-oxygenase-1 (HO-1) and is an inhibitor of transcriptional co-activator p300. A novel water soluble curcumin derivative (NCD) has been developed to overcome low invivo bioavailability of curcumin. We evaluated the effect of the NCD on signaling mechanisms involved in cardiomyocyte hypertrophy and studied whether its action is mediated via inducible HO-1. Rats were divided into controls, controls receiving NCD, diabetic, diabetic receiving NCD, diabetic receiving pure curcumin, diabetic receiving HO inhibitor, zinc protoporphyrin IX (ZnPP IX) and diabetic receiving NCD and ZnPP IX. NCD and curcumin were given orally. After 45 days, cardiac physiologic parameters, plasma glucose, insulin, glycated hemoglobin (GHb), HO-1 gene expression and HO activity in pancreas and cardiac tissues were assessed. Gene expression of p300, atrial natriuretic peptide (ANP) and myocyte enhancer factor 2 (MEF2A and MEF2C) were studied. NCD and curcumin decreased plasma glucose, GHb and increased insulin levels significantly in diabetic rats. This action may be partially mediated by induction of HO-1 gene. HO-1 gene expression and HO activity were significantly increased in diabetic heart and pancreas. Diabetes upregulated the expression of ANP, MEF2A, MEF2C and p300. NCD and curcumin prevented diabetes-induced upregulation of these parameters and improved left ventricular function. The effect of the NCD was better than the same dose of curcumin.

Stem cell‐based therapy targeted at the penile tissue has been lately considered in preclinical studies. This work aimed to assess the effect of intracavernous administration of mesenchymal stem cells (MSCs) in aged rats (n = 100). They were subjected to single intracavernous injection (ICI) of 1.0 million MSCs, followed up for 3, 4 weeks, 3 and 4 months (each group 25 rats) and compared with both adult and aged controls (n = 50). In dissected cavernous tissues, cGMP and histopathology were assessed in addition to intracavernous pressure (ICP) measurement in some anaesthetised rats. The results showed that cavernous tissue cGMP was significantly increased in MSCs transplanted rats in all investigated groups compared with the controls. The mean cavernous cGMP levels after 3 and 4 months of MSCs transplantation were significantly increased compared with those after 3 or 4 weeks. Cavernous tissue ICP measurement showed significant increase in MSCs transplanted groups compared with the controls, more in the long‐term follow up than in the shorter one. Histopathological examination detected markedly dilated sinusoidal vascular spaces in the long‐term follow‐up study. It is concluded that stem cell‐based therapy is feasible for age‐associated erectile dysfunction and could improve erectile signaling.