Epigenetic Reexpression of Hemoglobin F Using Reversible LSD1 Inhibitors: Potential Therapies for Sickle Cell Disease.

Sickle cell disease (SCD) is caused by a single nucleotide polymorphism on chromosome 11 in the β-globin gene. The resulting mutant hemoglobin S (HbS) is a poor oxygen transporter and causes a variety of vascular symptoms and organ failures. At birth, the DRED epigenetic complex forms and silences the γ-globin gene, and fetal hemoglobin (HbF, 2 α-, and 2 γ-subunits) is replaced by adult HbA (αβ) or HbS (αβ ) in SCD patients.

Spermine oxidase mediates Helicobacter pylori-induced gastric inflammation, DNA damage, and carcinogenic signaling.

Helicobacter pylori infection is the main risk factor for the development of gastric cancer, the third leading cause of cancer death worldwide. H. pylori colonizes the human gastric mucosa and persists for decades.

Dual inhibitors of LSD1 and spermine oxidase.

We have previously described the synthesis and evaluation of 3,5-diamino-1,2,4-triazole analogues as inhibitors of the flavin-dependent histone demethylase LSD1. These compounds are potent inhibitors of LSD1 without activity against monoamine oxidases A and B, and promote the elevation of H3K4me2 levels in tumor cells . We now report that the cytotoxicity of these analogues in pancreatic tumor cells correlates with the overexpression of LSD1 in each tumor type.

Effects of Crude Oil/Dispersant Mixture and Dispersant Components on PPARγ Activity in Vitro and in Vivo: Identification of Dioctyl Sodium Sulfosuccinate (DOSS; CAS #577-11-7) as a Probable Obesogen.

Background: The obesity pandemic is associated with multiple major health concerns. In addition to diet and lifestyle, there is increasing evidence that environmental exposures to chemicals known as obesogens also may promote obesity.

Objectives: We investigated the massive environmental contamination resulting from the Deepwater Horizon (DWH) oil spill, including the use of the oil dispersant COREXIT in remediation efforts, to determine whether obesogens were released into the environment during this incident.

Structure-activity study for (bis)ureidopropyl- and (bis)thioureidopropyldiamine LSD1 inhibitors with 3-5-3 and 3-6-3 carbon backbone architectures.

Methylation at specific histone lysine residues is a critical post-translational modification that alters chromatin architecture, and dysregulated lysine methylation/demethylation is associated with the silencing of tumor suppressor genes. The enzyme lysine-specific demethylase 1 (LSD1) complexed to specific transcription factors catalyzes the oxidative demethylation of mono- and dimethyllysine 4 of histone H3 (H3K4me and H3K4me2, respectively). We have previously reported potent (bis)urea and (bis)thiourea LSD1 inhibitors that increase cellular levels of H3K4me and H3K4me2, promote the re-expression of silenced tumor suppressor genes and suppress tumor growth in vitro.

3,5-Diamino-1,2,4-triazoles as a novel scaffold for potent, reversible LSD1 (KDM1A) inhibitors.

The chromatin remodeling amine oxidase lysine-specific demethylase 1 (LSD1) has become an attractive target for the design of specific inhibitors with therapeutic potential. We, and others, have described LSD1 inhibitors that have potential as antitumor agents. Many of the currently known LSD1 inhibitors are poor drug candidates, or are structurally based on the tranylcypromine backbone, thus increasing the potential for off-target effects mediated by other amine oxidases.

Chronic suppression of insulin by diazoxide alters the activities of key enzymes regulating hepatic gluconeogenesis in Zucker rats.

Objectives: Chronic attenuation of hyperinsulinemia by diazoxide (DZ), an inhibitor of glucose-mediated insulin secretion, improved insulin sensitivity and glucose tolerance and caused down-regulation of lipid metabolizing enzymes in adipose tissue and decreased the rate of weight gain in mildly hyperglycemic obese Zucker rats. Since the liver plays a central role in glucose homeostasis, we studied the effect of chronic insulin suppression on key insulin-sensitive enzymes regulating hepatic gluconeogenesis.

Methods: DZ (150 mg/kg per day) or vehicle (control) was administered to 7-week-old female obese and lean Zucker rats for a period of 4 weeks.

Beneficial effects of metformin in normoglycemic morbidly obese adolescents.

Hyperinsulinemia and insulin resistance are common features of obesity in humans and experimental animals. It has been demonstrated that metformin, an antihyperglycemic agent, decreases hyperinsulinemia and insulin resistance leading to decreased adiposity in obese and non-insulin-dependent diabetes mellitus (NIDDM) adults. To evaluate the antiobesity effect of metformin, we conducted a randomized double-blind placebo controlled trial in 24 hyperinsulinemic nondiabetic obese adolescents (body mass index [BMI] >30 kg/m(2)).

Diazoxide effects on hypothalamic and extra-hypothalamic NPY content in Zucker rats.

To determine if the anorectic effects of the insulin antagonist diazoxide (DZ) are mediated by reduced central neuropeptide Y (NPY), female Zucker rats, given DZ (150 mg/kg/day) or placebo for about four weeks, were sacrificed following overnight fasting or free feeding. Several hypothalamic and extra-hypothalamic nuclei were extracted for NPY content. DZ reduced weight gain in obese rats and lowered glucose of lean and obese rats without affecting insulin.

Effect of diazoxide on brain capillary insulin receptor binding and food intake in hyperphagic obese Zucker rats.

Insulin is believed to act as a central adiposity signal by binding to hypothalamic and other brain insulin receptors. Entry of circulating insulin into the brain is accomplished by a saturable receptor-mediated transendothelial transport system and is believed to be impaired in hyperinsulinemic, insulin-resistant, and hyperphagic obese Zucker rats. Theoretically, if hyperinsulinemia is decreased simultaneously while brain capillary insulin binding is increased, uptake of insulin into the brain can be enhanced leading to reduced food intake.

Verapamil reduces glucose and fatty acid metabolism of beating and nonbeating rat heart cells.

The effects of various dosages of verapamil on glucose or fatty acid utilization by beating or nonbeating rat heart myocytes in tissue culture were determined. Myocytes were incubated with verapamil and either D-6-14C glucose or 1-14C palmitic acid as substrate. After incubation the subsequently generated 14CO2 was captured with hyamine hydroxide and the equivalent oxygen values were calculated.

C-6 glioma growth in rats: suppression with a beta-adrenergic agonist and a phosphodiesterase inhibitor.

Rat C-6 glioma possesses a beta-adrenergic receptor which, when activated, raises intracellular levels of cyclic adenosine monophosphate (cAMP) in cultured C-6 glioma cells. The present study shows that growth of C-6 glioma is suppressed in rats treated with the beta-adrenergic agonist isoproterenol. Addition of papaverine, a cAMP phosphodiesterase inhibitor, to the treatment schedule augments this effect.

Effect of "restricted ovulator" gene on uptake of yolk-precursor protein.

The bulk of the yolk proteins and lipoproteins constituting the yolks of mature oocytes in birds are synthesized by the liver and transported via the plasma to the oocytes where they are incorporated by micropinocytosis. Evidence is presented indicating that oocytes of hens possessing a mutation identified by Jones, Briles, and Schjeide as a "restricted ovulator gene" fail to incorporate normal amounts and proportions of low density lipoproteins, lipovitellin and possible other proteins making up the bulk of the yolk material. Plasma albumin is taken into the yolks but the other proteins synthesized by the liver for deposition within the oocytes accumulate in the plasma, attaining very high levels.