ABSTRACT
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.
ABSTRACT
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.
ABSTRACT
Pseudomonas sp. TS1138 isolated from soil samples was able to form L-cysteine from DL-2-Amino-△2-Thia-zoline-4-Carboxylic Acid (DL-ATC) after cultured 16 hours . The optimum carbon and nitrogen soruces of strain growth and enzyme formation are glucose and urea. This enzyme was induced by DL-ATC. The product was identified to be L-Cysteine based on thin layer chromatography, optical rotation and HPLC studies.
ABSTRACT
The L-cysteine desulfhydrase gene (cd) of Pseudomonas sp.TS1138 was amplified by PCR,and the amplified gene was recombined in the cloning vector pBluescript SKII.The 1.2kb DNA fragment containing cd was sequenced,and its homology with other desulfhydrases was blast; then the cd was cloned into the expression vector pET-21a(+), and afterward expressed by IPTG inducement.The expression protein was purified by Ni-NTA His-Bind Resin.Then the expression protein was identified by the method of activity staining of desulfhydrase, and the characterization of L-cysteine desulfhydrase and the critical role it played in the L-cysteine biosynthetic pathway were discussed.
ABSTRACT
The L-ATC hydrolase and L-SCC amidohydrolase which convert L-ATC to L-cysteine in Pseudomonas sp.TS-1138 are purified about 83.9 and 90.3 fold by salting-out method, Sephadex G-75 gel chromatography, DEAE-cellulose 52 ion exchange and Sephadex G-100 gel chromatography, etc. The purified enzyemes are both demonstrated by SDS-PAGE to be a homogeneous protein. Their molecular weight are about 37.5kD and42.8kDa respectively. The optimum reaction temperature are both 35℃, and the optimum pH are 7.0 and 8.0 respectively. The Km of the two enzymes are 0.67 mmol/L and 0.15 mmol/L, and the Vmax are 0.39?10 -3mmol/L?min and 0.42?10 -3mmol/L?min respectively.