Gamma-oryzanol (OR), a phytosteryl ferulate mixture extracted from rice bran oil, has a wide spectrum of biological activities in particular, it has antioxidant properties.
Gestational diabetes (GD) is a common complication during pregnancy. Metabolic changes in GD affect fetal development and fetal glucose homeostasis. The present study utilized a rat model of GD to evaluate the effects of nicotinamide on diabetic parameters; antioxidant gene expression viz, superoxide dismutase (SOD) and catalase (CAT); reactive oxygen species (ROS) production by neutrophils and enhancement of lymphocyte mediated immune response. Nicotinamide (50, 100 and 200 mg/kg) was orally supplemented to gestational diabetic rats from days 6 through 20 of gestation. After GD induction, the control group had elevated glucose and reduced insulin while nicotinamide (100 & 200 mg/kg) supplementation reversed these changes. The same doses of nicotinamide upregulated mRNA expressions of SOD and CAT genes in liver but reduced the oxidative burst activity of neutrophils in response to phorbol myristate acetate (PMA), N-formyl-methionyl-leucyl-phenylalanine (FMLP) or E. coli activation. Nicotinamide (100 & 200 mg/kg) supplementation also increased expression of activated T helper (CD4+CD25+) cells and induced proliferation of splenocytes. These findings provide evidence for utilizing nicotinamide as supplement or adjunct to support existing therapeutic agents for gestational diabetes and in pregnant individuals with weakened immune systems.
Gestational diabetes mellitus (GDM) is a common complication during pregnancy. Metabolic changes in GDM affect fetal development and fetal glucose homeostasis. Several complications of diabetes are related to increased intracellular oxidative stress where prooxidants exceed antioxidant capacity. The present study was initiated to evaluate the effects of nicotinamide on CD4+CD25+ regulatory T cells (Tregs), proliferation of splenocytes, production of reactive oxygen species (ROS) by neutrophils and serum glucose levels. Changes in mRNA levels of two antioxidant genes in liver, viz, superoxide dismutase (SOD1) and catalase (CAT) were quantified with real-time PCR (QRT-PCR). Nicotinamide (50, 100 and 200 mg/kg) was supplemented p.o. to pregnant diabetic rats from days 6 through 20 of gestation. The highest dose enhanced expression of Tregs and increased splenocytes proliferation in both resting and lipopolysaccharide (LPS)-stimulated cells. Oxidative burst activity of neutrophils in response to phorbol myristate acetate (PMA), N-formyl-methionyl-leucyl-phenylalanine (FMLP) or E. coli activation was reduced. mRNA expressions of superoxide dismutase (SOD) and catalase (CAT) genes were upregulated by nicotinamide. In summary, nicotinamide boosted the immune system through stimulation of adaptive immune cells with enhancement of antioxidant defences and reduced production of ROS. Serum glucose level was normalised by nicotinamide (200 mg/kg). These findings provide evidence for usage of nicotinamide as a supplement or as adjunct to therapeutic agents in gestational diabetes and in pregnant individuals with weakened immune systems.