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Background and objectives: Anemia and chronic kidney disease (CKD) are common findings in diabetic patients. Lack of glycemic control is associated with increased risk of diabetic complications. This study aimed to determine the effect of poor glycemic control on the prevalence and determinants of anemia and CKD among type 2 diabetes mellitus (T2DM) patients in Jordan. Methods: A cross-sectional study design was used in this research. T2DM patients with controlled diabetes (HbA1c ≤7.0%, n = 120) and age-, gender- and body mass index–matched uncontrolled diabetic patients (HbA1c >7.0%, n = 120) were recruited. Blood sample for HbA1c and serum insulin measurement were obtained. Complete blood count and kidney function test results were obtained from the patient's medical records. Anemia was determined according to World Health Organization criteria. A binomial logistic regression was performed to ascertain the effects of age, gender, CKD and glycemic control on the likelihood that participants have anemia. Results: The prevalence of anemia was significantly higher in the uncontrolled T2DM compared to controlled T2DM patients (40% vs 27.5%, OR: 2.14, 95% CI: 1.23, 3.71, P = 0.006). Female patients with uncontrolled T2DM had significantly greater prevalence of anemia compared to male patients with uncontrolled T2DM. The binomial logistic regression analysis showed that age, female gender, and CKD were positively associated with anemia in the multivariate model, while in the univariate model, lack of glycemic control increases the odds of anemia by 1.74 (95% CI: 1.01, 2.99, P = 0.046). Conclusion: Anemia is commonly present among T2DM patients in Jordan and is associated with poor glycemic control especially in females. These results emphasize the necessity of including anemia screening in standard diabetes care to enable early detection and treatment of anemia and to enhance the overall care of diabetic patients. [ABSTRACT FROM AUTHOR]

Transglutaminase (TG) isoforms control diverse normal and pathophysiologic processes through their capacity to cross-link extracellular matrix (ECM) proteins. Their functional and signalling roles in cardiac fibrosis remain poorly understood, despite some evidence of TG2 involvement in abnormal ECM remodelling in heart diseases. In this study, we investigated the role of TG1 and TG2 in mediating fibrotic signalling, collagen cross-linking, and cell proliferation in healthy fibroblasts by siRNA-mediated knockdown. siRNA for TG1, TG2 or negative control was transfected into cultured neonatal rat ventricular fibroblasts and cardiomyocytes. mRNA expression of TGs and profibrotic, proliferation and apoptotic markers was assessed by qPCR. Cell proliferation and soluble and insoluble collagen were determined by ELISA and LC-MS/MS, respectively. TG1 and TG2 were both expressed in neonatal rat cardiomyocytes and fibroblasts before transfection. Other TGs were not detected before and after transfection. TG2 was predominantly expressed and more effectively silenced than TG1. Knocking down TG1 or TG2 significantly modified profibrotic markers mRNA expression in fibroblasts, decreasing connective tissue growth factor (CTGF) and increasing transforming growth factor-β1 compared to the negative siRNA control. Reduced expression of collagen 3A1 was found upon TG1 knockdown, while TG2 knockdown raised α-smooth muscle actin expression. TG2 knockdown further increased fibroblast proliferation and the expression of proliferation marker cyclin D1. Lower insoluble collagen content and collagen cross-linking were evidenced upon silencing TG1 or TG2. Transcript levels of collagen 1A1, fibronectin 1, matrix metalloproteinase-2, cyclin E2, and BCL-2-associated X protein/B-cell lymphoma 2 ratio were strongly correlated with TG1 mRNA expression, whereas TG2 expression correlated strongly with CTGF mRNA abundance. These findings support a functional and signalling role for TG1 and TG2 from fibroblasts in regulating key processes underlying myocardial ECM homeostasis and dysregulation, suggesting that these isoforms could be potential and promising targets for the development of cardiac fibrosis therapies. [ABSTRACT FROM AUTHOR]

We examined expression of protease-activated receptors 2 (PAR2) and characterized their signaling pathways in rabbit gastric muscle cells. The PAR2 activating peptide SLIGRL (PAR2-AP) stimulated Gq, G13, Gi1, PI hydrolysis, and Rho kinase activity, and inhibited cAMP formation. Stimulation of PI hydrolysis was partly inhibited in cells expressing PAR2 siRNA, Gaq or Gai minigene and in cells treated with pertussis toxin, and augmented by expression of dominant negative regulator of G protein signaling (RGS4(N88S)). Stimulation of Rho kinase activity was abolished by PAR-2 or Ga13 siRNA, and by Ga13 minigene. PAR2-AP induced a biphasic contraction; initial contraction was selectively blocked by the inhibitor of PI hydrolysis (U73122) or MLC kinase (ML-9), whereas sustained contraction was selectively blocked by the Rho kinase inhibitor (Y27632). PAR2-AP induced phosphorylation of MLC20, MYPT1 but not CPI-17. PAR2-AP also caused a decrease in the association of NF-kB and PKA catalytic subunit: the effect of PAR2-AP was blocked by PAR2 siRNA or phosphorylation-deficient RhoA (RhoA(S188A)). PAR2-AP-induced degradation of IkBa and activation of NF-kB were abolished by the blockade of RhoA activity by Clostridium botulinum C3 exoenzyme suggesting RhoA-dependent activation of NF-kB. PAR2-AP-stimulated Rho kinase activity was significantly augmented by the inhibitors of PKA (myristoylated PKI), IKK2 (IKKIV) or NF-kB (MG132), and in cells expressing dominant negative mutants of IKK (IKK(K44A), IkBa (IkBa (S32A/S36A)) or RhoA(S188A), suggesting feedback inhibition of Rho kinase activity via PKA derived from NF-kB pathway. PAR2-AP induced phosphorylation of RhoA and the phosphorylation was attenuated in cells expressing phosphorylation-deficient RhoA(S188A). Our results identified signaling pathways activated by PAR2 to mediate smooth muscle contraction and a novel pathway for feedback inhibition of PAR2-stimulated RhoA. The pathway involves activation of the NF-kB to release catalytic subunit of PKA from its binding to IkBa and phosphorylation of RhoA at Ser188. [ABSTRACT FROM AUTHOR]