STZ-induced diabetes up-regulated the expression of AGE, RAGE, TGF- β1 and TGF- β1 receptors and down-regulated BDNF and TrkB in different layers of diabetic colon mainly due to hyperglycemia.
Compared with the control group, the diabetic, miR-27a mimics, and siPRKAA2 groups showed reduced weight and PRKAA2 expression, but elevated blood glucose, serum creatinine (sCr), blood urea nitrogen (BUN), cell apoptosis, and expression of TGF-β1, Smad3, FN, COL-I, CTGF, and p-Smad3.
Oxidative stress, generation of advanced glycation end products and activation of renin angiotensin system are the connecting links between hyperglycemia and TGF-β1 over expression.
The untreated diabetic group showed hyperglycemia and increased diuresis, creatinine clearance, proteinuria, glycosuria and urinary excretion of <i>N</i>-acetyl-β-d-glucosaminidase (NAG), as well as increased oxidative stress and the expression of interleukin 1β (IL-1β), IL-6, nuclear factor kappa beta (NFκβ) and transforming growth factor-β1 (TGF-β1) in plasma and kidney.
Together, these results suggested that losartan could alleviate the EMT in glomeruli via inhibition of oxidative stress damage and the TGF-β1/Smad signaling pathway under hyperglycemia.
In vitro, silencing of Nox5 in human mesangial cells was associated with attenuation of the hyperglycemia and TGF-β1-induced enhanced ROS production, increased expression of profibrotic and proinflammatory mediators, and increased TRPC6, PKC-α, and PKC-β expression.
Compared with the normal fat diet (chow)-fed SHRs, the HFD-fed SHRs developed a more intense degree of hyperglycemia and dyslipidemia and showed a constellation of left ventricular (LV) diastolic dysfunction, and exacerbated myocardial fibrosis, as well as activation of the TGF-β1 and Smad2/3 pathways.
This review focuses on describing how, through reductionist in vitro experimentation focusing on TGF-β1-related responses to hyperglycaemia, we have identified induced in high glucose-1 (IHG-1), induced in high glucose-2 (IHG-2/Grem1) and the lipoxin-inducible microRNA let-7c as potential targets for harnessing new therapeutic approaches to limit the bioactivity of TGF-β1 in diabetic kidney disease.
Among three TGFβ isoforms, TGF-β1 and β3 were upregulated in response to wounding in NL corneal epithelial cells (CECs), whereas the latter was greatly suppressed by hyperglycemia in rat type 1 and 2 and mouse type 1 DM models.
The in vivo experiments showed that a high-fat diet induced hyperglycaemia, hyperinsulinaemia and hypertriacylglycerolaemia, subsequent increases in sterol regulatory element binding protein-1 (SREBP-1) and transforming growth factor-β1 (TGF-β1), lipid droplet deposit in renal tubular cells and interstitial extracellular matrix accumulation in Wistar rats.
Active TGF-β(1), but not total TGF-β(1) was reduced with concurrent PXS25 in the presence of high glucose, but not in hyperglycemia+hypoxia conditions.
We determined the associations between esophagectomy-induced stress hyperglycemia (> or =30 mg/dl increases in blood glucose during surgery) and genetic polymorphisms for C-reactive protein (CRP), tumor necrosis factor (TNF)-alpha, -beta, interferon-gamma, transforming growth factor-beta1, interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-6 receptors, IL-10, IL-12beta, adiponectin, and peroxisome proliferator-activated receptor-gamma.
Rat islets (300 per mouse) transduced with an AAV2/5 vector harboring the immunosuppressive transgene, tgf beta 1, retain the ability to correct hyperglycemia when transplanted into immune-deficient diabetic mice.
We studied whether transforming growth factor beta1 (TGF-beta1) modulates human equilibrative nucleoside transporters 1 (hENT1) expression and activity in human umbilical vein endothelial cells (HUVECs). hENT1-mediated adenosine transport and expression are reduced in gestational diabetes and hyperglycaemia, conditions associated with increased synthesis and release of nitric oxide (NO) and TGF-beta1 in this cell type.
These data suggest that hyperglycemia induces intraglomerular TGF-beta 1 mRNA expression in vivo, and that TGF-beta 1 overproduction may be associated with the progression of diabetic nephropathy.