Nicotine exacerbates tacrolimus-induced renal injury by programmed cell death

Background/Aims@#Cigarette smoking is an important modifiable risk factor in kidney disease progression. However, the underlying mechanisms for this are lacking. This study aimed to assess whether nicotine (NIC), a major toxic component of cigarette smoking, would exacerbates tacrolimus (TAC)-induced renal injury. @*Methods@#Sprague-Dawley rats were treated daily with NIC, TAC, or both drugs for 4 weeks. The influence of NIC on TAC-caused renal injury was examined via renal function, histopathology, oxidative stress, mitochondria, endoplasmic reticulum (ER) stress, and programmed cell death (apoptosis and autophagy). @*Results@#Both NIC and TAC significantly impaired renal function and histopathology, while combined NIC and TAC treatment aggravated these parameters beyond the effects of either alone. Increased oxidative stress, ER stress, mitochondrial dysfunction, proinf lammatory and profibrotic cytokine expressions, and programmed cell death from either NIC or TAC were also aggravated by the two combined. @*Conclusions@#Our observations suggest that NIC exacerbates chronic TAC nephrotoxicity, implying that smoking cessation may be beneficial for transplant smokers taking TAC.

L-carnitine treatment attenuates renal tubulointerstitial fibrosis induced by unilateral ureteral obstruction

Background/Aims@#Accumulating evidence indicates that L-carnitine (LC) protects against multiorgan damage through its antioxidant properties and preservation of the mitochondria. Little information is available about the effects of LC on renal fibrosis. This study examined whether LC treatment would provide renoprotection in a rat model of unilateral ureteral obstruction (UUO) and in vitro. @*Methods@#Sprague-Dawley rats that underwent UUO were treated daily with LC for 7 or 14 days. The influence of LC on renal injury caused by UUO was evaluated by histopathology, and analysis of gene expression, oxidative stress, mitochondrial function, programmed cell death, and phosphatidylinositol 3-kinase (PI3K)/ AKT/forkhead box protein O 1a (FoxO1a) signaling. In addition, H2O2-exposed human kidney cells (HK-2) were treated with LC. @*Results@#LC treatment inhibited expression of proinflammatory and profibrotic cytokines, and was followed by a significant attenuation of tubulointerstitial inflammation and fibrosis. The increased oxidative stress caused by UUO was associated with mitochondrial dysfunction and excessive apoptosis and autophagy via PI3K/AKT/FoxO1a-dependent signaling, and this was abrogated by administration of LC. In H2O2-exposed HK-2 cells, LC decreased intracellular production of reactive oxygen species, and suppressed expression of profibrotic cytokines and reduced the number of apoptotic cells. @*Conclusions@#LC protects against the progression of tubulointerstitial fibrosis in an obstructed kidney.

Prevention and Treatment of Atherosclerosis by Three Different Chinese Medical Compounds: a Mechanism Study / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the effect of Buyang Huanwu Decoction (BHD), Xuefu Zhuyu Decoction (XZD), and Sijunzi Decoction (SD) contained serums on expressions of Toll-like receptor 4 (TLR4)/nuclear factor (NF)-κB signals, lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), tumor necrosis factor-α (TNF-α), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and to explore possible anti-atherosclerotic mechanisms.</p><p><b>METHODS</b>Twenty New Zealand rabbits were divided into 4 groups at random, i.e., the normal control group, the BHD group (6.7 g/kg), the XZD group (3.6 g/kg), and the SD group (1.6 g/kg), 5 in each group. All medication lasted for 7 successive days. Two h after the final medication, about 50 mL blood was withdrawn from rabbit heart for preparing serums. Human umbilical vein endothelial cell ECV304 were cultured in vitro for 18 h and randomly divided into the blank control group, the model group, the Western medicine (WM) control group, the BHD group, the XZD group, and the SD group at random. ECV304, except in the blank control group, were stimulated with lipopolysaccharide (LPS) for 2 h. Those in the WM control group and CM groups were treated respectively with corresponding CM contained serum for 24 h. Finally gene and protein expressions of TLR4, myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor-associated factor-6 (TRAF-6), NF-κB, LOX-1, TNF-α, ICAM-1, and VCAM-1 were detected by fluorescent quantitative PCR and Western blot.</p><p><b>RESULTS</b>Compared with the blank control group, mRNA expressions of TLR4, MyD88, TRAF-6, NF-KB, LOX-1 , TNF-cx, ICAM-1, and VCAM-1 increased significantly; protein expressions of TLR4, NF-κB, LOX-1, TNF-α, ICAM-1, and VCAM-1 also increased significantly in the model group (P < 0.01). Compared with the model group, mRNA and protein expressions of each index could be significantly inhibited in the BHD group, the XZD group, and the WM control group (P < 0.05). Besides, mRNA and protein expressions of each index could be significantly elevated more in the BHD group and the XZD group than in the WM control group (P < 0.05). No statistical difference existed in each index between the SD group and the rest groups (P > 0.05).</p><p><b>CONCLUSIONS</b>The mechanism of BHD and XZD for fighting against atherosclerosis might be associated with inhibiting TLR4/NF-κB signal transduction pathway and expressions of its downstream inflammatory factors such as LOX-1, TNF-α, ICAM-1, and VCAM-1. But SD showed no associated effect on atherosclerosis.</p>

Effects of yiqi huoxue compound contained drug serum on the expressions of toll-like receptor 4 and downstream signal transduction pathway, and LOX-1, TNF-alpha, ICAM-1 in the human vein endothelial cells / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the effects of Yiqi Huoxue Compound (YHC) contained drug serum on the expressions of TLR4 and its downstream signal transduction pathway and LOX-1, TNF-alpha, ICAM-1 in human umbilical vein endothelial cells (HUVECs), and to study its possible anti-atherosclerosis (AS) mechanism. METHODS Twenty New Zealand rabbits were divided into 4 groups in random, i. e., the normal control group, the high concentration group, the middle concentration group, and the low concentration group, 5 in each group. Normal saline was given to rabbits in the normal control group by gastrogavage. High, middle, and low concentration of YHC was respectively given to rabbits in the rest 3 groups by gastrogavage for 7 successive days. The blood was withdrawn from the heart 2 h after the last gastrogavage. The serum was isolated after centrifuge. HUVECs was in vitro cultured and then randomly divided into 6 groups, i. e., the normal control group, the model group, the Western medicine control group, the high, middle, and low YHC groups. HUVECs were stimulated with LPS for 2 h, and then treated with high, middle, and low YHC contained serum. HUVECs were collected 24 h later. The gene expressions of TLR4, MyD88, TRAF-6, TRAM, TRIF, NF-kappaB, LOX-1, TNF-alpha, and ICAM-1 were detected using fluorescent quantitative PCR. The protein expressions of TLR4, MyD88, TRAF-6, and LOX-1 were determined using Western blot method.</p><p><b>RESULTS</b>After HUVECs were stimulated by LPS, the expressions of TLR4, MyD88, TRAF-6, TRAM, TRIF, NF-kappaB, LOX-1, TNF-alpha, and ICAM-1 were enhanced, showing statistical difference when compared with the vehicle control group (P < 0.01). YHC contained serum significantly decreased the higher expressions of TLR4, MyD88, TRAF-6, NF-kappaB, LOX-1, TNF-alpha, and ICAM-1, showing statistical difference when compared with the model group (P < 0.05).</p><p><b>CONCLUSIONS</b>YHC could inhibit the TLR signal transduction pathway and the expressions of LOX-1, TNF-alpha, and ICAM-1. These might be one of the mechanisms for treating various immune inflammatory diseases and preventing AS.</p>