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Glomerular mesangial cells (GMCs) activation is implicated in the pathogenesis of diabetic nephropathy (DN). Our previous study revealed that high glucose (HG)-treated glomerular endothelial cells (GECs) produce an increased number of TGF-[Formula: see text]1-containing exosomes to activate GMCs through the TGF-[Formula: see text]1/Smad3 signaling pathway. We also identified that Tongxinluo (TXL), a traditional Chinese medicine, has beneficial effects on the treatment of DN in DN patients and type 2 diabetic mice. However, it remained elusive whether TXL could ameliorate renal structure and function through suppression of intercellular transfer of TGF-[Formula: see text]1-containing exosomes from GECs to GMCs. In this study, we demonstrate that TXL can inhibit the secretion of TGF-[Formula: see text]1-containing exosomes from HG-treated GECs. Furthermore, exosomes produced by HG induced-GECs treated with TXL cannot trigger GMC activation, proliferation and extracellular matrix (ECM) overproduction both in vitro and in vivo. These results suggest that TXL can prevent the transfer of TGF-[Formula: see text]1 from GECs to GMCs via exosomes, which may be one of the mechanisms of TXL in the treatment of DN.

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Epithelial-to-mesenchymal transition (EMT) plays an important role in renal interstitial fibrosis (RIF) with diabetic nephropathy (DN). Smad7 (a inhibitory smad), a downstream signaling molecules of TGF-ß1, represses the EMT. The physiological function of miR-21 is closely linked to EMT and RIF. However, it remained unclear whether miR-21 over-expression affected TGF-ß1-induced EMT by regulating smad7 in DN. In this study, real-time RT-PCR, cell transfection, luciferase reporter gene assays, western blot and confocal microscope were used, respectively. Here, we found that miR-21 expression was upregulated by TGF-ß1 in time- and concentration -dependent manner. Moreover, miR-21 over-expression enhanced TGF-ß1-induced EMT(upregulation of a-SMA and downregulation of E-cadherin) by directly down-regulating smad7/p-smad7 and indirectly up-regulating smad3/p-smad3, accompanied by the decrease of Ccr and the increase of col-IV, FN, the content of collagen fibers, RTBM, RTIAW and ACR. Meantime, the siRNA experiment showed that smad7 can directly regulate a-SMA and E-cadherin expression. More importantly, miR-21 inhibitor can not only inhibit EMT and fibrosis but also ameliorate renal structure and function. In conclusion, our results demonstrated that miR-21 overexpression can contribute to TGF-ß1-induced EMT by inhibiting target smad7, and that targeting miR-21 may be a better alternative to directly suppress TGF-ß1-mediated fibrosis in DN.

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Diabetic nephropathy (DN) is one of the most important diabetic microangiopathies. The epithelial-to-mesenchymal transition (EMT) plays an important role in DN. The physiological role of microRNA-21 (miR-21) was closely linked to EMT. However, it remained elusive whether tongxinluo (TXL) ameliorated renal structure and function by regulating miR-21-induced EMT in DN. This study aimed to determine the effect of TXL on miR-21-induced renal tubular EMT and to explore the relationship between miR-21 and TGF-ß1/smads signals. Real-time RT-PCR, cell transfection, in situ hybridization (ISH), and laser confocal microscopy were used, respectively. Here, we revealed that TXL dose dependently lowered miR-21 expression in tissue, serum, and cells. Overexpression of miR-21 can enhance α-smooth muscle actin (SMA) expression and decrease E-cadherin expression by upregulating smad3/p-smad3 expression and downregulating smad7 expression. Interestingly, TXL also increased E-cadherin expression and decreased α-SMA expression by regulating miR-21 expression. More importantly, TXL decreased collagen IV, fibronectin, glomerular basement membrane, glomerular area, and the albumin/creatinine ratio, whereas it increased the creatinine clearance ratio. The results demonstrated that TXL ameliorated renal structure and function by regulating miR-21-induced EMT, which was one of the mechanisms to protect against DN, and that miR-21 may be one of the therapeutic targets for TXL in DN.

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Diabetic peripheral neuropathy (DPN) is a common microvascular complication of diabetes associated with high disability rate and low quality of life. Tang-Luo-Ning (TLN) is an effective traditional Chinese medicine for the treatment of DPN. To illustrate the underlying neural protection mechanisms of TLN, the effect of TLN on electrophysiology and sciatic nerve morphology was investigated in a model of streptozotocin-induced DPN, as well as the underlying mechanism. Sciatic motor nerve conduction velocity and digital sensory nerve conduction velocity were reduced in DPN and were significantly improved by TLN or α -lipoic acid at 10 and 20 weeks after streptozotocin injection. It was demonstrated that TLN intervention for 20 weeks significantly alleviated pathological injury as well as increased the phosphorylation of ErbB2, Erk, Bad (Ser112), and the mRNA expression of neuregulin 1 (Nrg1), GRB2-associated binding protein 1 (Gab1), and mammalian target of rapamycin (Mtor) in injured sciatic nerve. These novel therapeutic properties of TLN to promote Schwann cell survival may offer a promising alternative medicine for the patients to delay the progression of DPN. The underlying mechanism may be that TLN exerts neural protection effect after sciatic nerve injury through Nrg1/ErbB2→Erk/Bad Schwann cell survival signaling pathway.

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OBJECTIVE: To investigate the clinical features of capillary leak syndrome (CLS) in children with sepsis, and to analyze its risk factors. METHODS: Clinical data of 384 children with sepsis was studied retrospectively. They included 304 cases of general sepsis, 54 cases of severe sepsis and 26 cases of septic shock, and were divided into non-CLS (n=356) and CLS groups (n=28). Univariate analysis was performed for each of the following variables: sex, age, malnutrition, anemia, coagulation disorders, white blood cell count, C-reactive protein (CRP), procalcitonin (PCT), tumor necrosis factor (TNF), interleukin (IL)-1, IL-6, blood glucose, lactic acid, Pediatric Risk of Mortality (PRISM) III score, pediatric critical illness score (PICS), severe sepsis and number of failed organs≥3. The statistically significant variables (as independent variables) were subjected to multivariate logistic regression analysis. RESULTS: The incidence rate of CLS in children with septic shock, severe sepsis and general sepsis were 42.3%, 20.1% and 1.3%, respectively, with significant differences among them (P<0.01). There were significant differences in anemia, coagulation disorders, CRP, PCT>2 ng/mL, TNF, IL-1, IL-6, blood glucose, lactic acid, PRISM III score, PICS and number of failed organs≥3 between the non-CLS and CLS groups (P<0.05). Severe sepsis/shock and PRISM III score were the independent risk factors for CLS in children with sepsis. CONCLUSIONS: The severity of sepsis and PRISM III score are positively correlated with the incidence of CLS in children with sepsis. Early monitoring of such factors as infection markers and blood glucose in children with severe sepsis and high PRISM III score may contribute to early diagnosis and effective intervention, thus reducing the mortality from CLS in children with sepsis.

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