Pathological Changes In Kidney Research Articles

葛根素对糖尿病大鼠肾组织中CXCL10/CXCR3表达影响的实验研究

目的：观察葛根素对糖尿病(Diabetes Mellitus, DM)大鼠肾组织病理形态、肾组织中趋化因子CXCL10以及受体CXCR3表达的影响，探讨葛根素延缓DM大鼠肾组织损伤的机理。方法：采用链脲佐菌素制备DM大鼠模型，将造模成功后的大鼠随机分为DM组(n = 11)、DM组+葛根素干预组(下文简称葛根素组) (n = 11)，并设置正常对照组(n = 7)。每2周测定一次各组大鼠空腹血糖、体重。4周后处死大鼠并取大鼠肾脏，对肾脏进行相关处理后，在光镜和电镜下观察大鼠肾组织病理改变，通过RT-PCR检测肾组织CXCL10/CXCR3mRNA的表达水平。结果：在电镜下显示：相较于DM组，葛根素组大鼠肾组织结构破坏程度明显减轻。RT-PCR结果显示：相较于DM组，葛根素组大鼠肾组织中趋化因子受体CXCR3的表达水平明显降低(p 0.05)。结论：葛根素可能通过降低肾组织中CXCR3的表达水平减轻肾组织的炎症反应，延缓DM大鼠肾组织的损伤。 Object: To observe the kidney pathological changes and the expressions of CXCR3/CXCL10 in kidney of diabetic rats under the effect of Puerarin. Methods: Diabetes Mellitus (DM) model rats were established by injecting streptozocin (STZ). Then the successful modeled rats were re-divided into two groups: the DM group (n = 11) and the Puerarin group (n = 11). The normal group (n = 7) was added too. The rats’ fasting plasma glucose levels and weight were detected every 2 weeks. The excision of rats’ renal was finished 4 weeks later. The pathological changes in renal tissues were examined by optical microscopy and electron microscope, and the expression levels of CXCL10/ CXCR3 were detected by RT-PCR. Results: Compared with the DM group, the renal injury, showed by electron microscope, was lessened significantly; the expression of CXCR3, showed by the results of RT-PCR, was reduced effectively in rats’ renal of the Puerarin group (p 0.05). Conclusion: One possible reason, for lessening injury of DM rats’ renal by Puerarin, is that Puerarin relieves the inflammation by reducing the expression level of CXCR3.

Study on the kidney impairment and expressions of FGF21 from a rat model of vascular calcification

Objective: To investigate the injury and pathological changes of kidney in a rat model of aortic vascular calcification and to explore the expressions of fibroblast growth factor 21 (FGF21). Methods: A total of 14 Spraugue Dawley (SD) rats were randomly divided into two groups: control group and vitamin D3+ nicotine (VDN) group, with 7 rats in each group.The rats in VDN group received vitamin D3 and nicotine to induce vascular calcification.The content of serum creatinine was determined by sarcosine oxidase method.Alkaline phosphatases (ALP) activity was detected by ALP detection kit.The protein levels of FGF21 were measured by radioimmunoassay (RIA). The structure of kidney was observed by hematoxylin and eosin staining. Results: The serum concentration of creatinine in VDN group was significantly higher than control group[(34.00±4.69) vs (27.17±5.38) μmol/L, P<0.05], and the renal pathological changes in VDN group were more apparent. ALP activity in VDN group was significantly higher than that in control group[(62.59±22.62) vs (29.89±11.78) U/g, P<0.05]. Expression of FGF21 in VDN group increased obviously, compared with that in control group[(0.583±0.340) vs (0.207±0.105) ng/mg, P<0.05]. Meanwhile, the elevated levels of FGF21 were positively correlated with up-regulation of ALP in calcified kidneys (r=0.878, P<0.05). Conclusions: Flushing dose of vitamin D3 and nicotine can induce the change of pathology and function of the kidney.Meanwhile, the expression of FGF21 in kidney up-regulated significantly, suggesting that FGF21 may be involved in the occurrence and development of vascular calcification and subsequent kidney injury.

Kidney histotexure and serum creatinine level in response to concurrent administration of alcohol and coffee in mice

The effect of alcohol and coffee on renal function with pathological changes in kidney was determined in mice. Sixty Albino mice were randomly divided into six equal groups. The mice of group A were maintained as control and remaining five groups were used as treated groups. The mice of control group were supplied with normal mice pellets whereas other groups were supplied with same pellets in addition to 5% coffee (in drinking water), 10% coffee, 10% alcohol, 5% coffee plus 5% alcohol and 10% coffee plus 10% alcohol, for 90 days. The serum creatinine level was significantly (P&lt;0.01) higher in groups supplied with alcohol. There was huge infiltration of reactive cells and mild haemorrhagic spots in kidney of mice that received 10% coffee and 10% alcohol, respectively. It is suggested that long use of high doses of alcohol and coffee impaired kidney function.Bangl. vet. 2015. Vol. 32, No. 2, 42-47

Antioxidant and anti-inflammatory effects of Nasturtium officinale involved in attenuation of gentamicin-induced nephrotoxicity

Background and purpose: Gentamicin (GM) is used against bacterial infections. The aim of our investigation was to evaluate the role of inflammation and also oxidative damage in nephrotoxic potential of GM and protective effects of Nasturtium officinale (watercress) against GM-induced nephrotoxicity in Wistar rats.Material and methods: The animals were divided into eight groups: control, solvent, GM (80 mg/kg IP), GM with three doses (50, 100 and 200 mg/kg/d) of hydroalcoholic extract of watercress and one group only received high dose of extract and a group which received GM plus vitamin E for 10 consecutive days. Then, the animals were killed and kidney tissues were separated. Finally reactive oxygen species (ROS), glutathione (GSH) content, lipid peroxidation (LPO), protein carbonyl (PCO), nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α) were evaluated. Also, pathological examination and measuring of blood urea nitrogen (BUN) and creatinine (Cr) were done.Results: The administration of GM for 10 d resulted in an increase in kidney markers (BUN and Cr) and pathological changes in kidney tissue. Also, oxidative stress was evident in GM group by increased ROS, LPO and PCO level and GSH oxidation. Increased in inflammation process was shown by increase in NO and TNF-α. Administration of watercress extract was able to protect against deterioration in nephrotoxic markers and suppressed the increase in oxidative stress and inflammation markers.Conclusions: Our study showed the critical role of oxidative damage and inflammation in GM-induced nephrotoxicity that markedly inhibited by administration of watercress. Therefore, watercress can be suggested for prevention of GM-induced nephrotoxicity.

Melatonin can attenuate ciprofloxacin induced nephrotoxicity: Involvement of nitric oxide and TNF-α.

Ciprofloxacin is a synthetic broad-spectrum antimicrobial agent of fluoroquinolone family. The aim of our investigation was to evaluate the role of oxidative damage and inflammation in nephrotoxic potential of Ciprofloxacin and protective effects of melatonin against its nephrotoxicity in male Wistar rats. The animals were divided into six groups: Control, ciprofloxacin (100mg/kg/day, i.p), ciprofloxacin with three doses (2.5, 5 and 10mg/kg/day) of melatonin and a group which received ciprofloxacin (100mg/kg/day) plus vitamin E (100mg/kg/day) for 8 consecutive days. 24h after last injection, the animals were euthanized and kidney tissues were separated. Finally reactive oxygen species, glutathione content, lipid peroxidation, protein carbonyl, nitric oxide and TNF-α were evaluated. Also, pathological examination and measuring of kidney biochemical markers (BUN and Cr) were done. The administration of ciprofloxacin for 8days resulted in significant increase (P<0.01) in kidney biomarkers (BUN and Cr) and pathological changes. Also, Oxidative stress was evident in ciprofloxacin group by significantly (p<0.001) increased reactive oxygen species, lipid peroxidation and protein carbonyl level and decreased glutathione content (p<0.001). Increased in inflammation process was shown by increase in NO and TNF-α (P<0.001). Administration of melatonin was able to protect against deterioration in nephrotoxic markers and suppressed the increase in oxidative stress and inflammatory markers. Our study showed the critical role of oxidative damage and inflammation in ciprofloxacin-induced nephrotoxicity that markedly inhibited by administration of melatonin. So, melatonin can be suggested for prevention of ciprofloxacin-induced nephrotoxicity.

Ozone therapy could attenuate tubulointerstitial injury in adenine-induced CKD rats by mediating Nrf2 and NF-κB.

This study aims to determine the effects of ozone therapy on restoring impaired Nrf2 activation to ameliorate chronic tubulointerstitial injury in rats with adenine-induced CKD. Sprague-Dawley rats were fed with 0.75% adenine-containing diet to induce CKD and chronic tubulointerstitial injury. Ozone therapy was administered by rectal insufflation. After 4 weeks, serum and kidney samples were collected and analyzed. Renal function and systemic electrolyte level were detected. Pathological changes in kidney were assessed by hematoxylin-eosin staining and Masson trichrome staining. Nrf2 activation was detected by immunohistochemistry and Western blot analyses. The levels of SOD, CAT, GSH, PCO, and MDA were detected in the kidney. Immunohistochemistry, Western blot, and real-time PCR analyses were performed to evaluate the activation of the nuclear factor kappa B (NF-κB) P65 pathway and inflammation infiltration in the tubulointerstitium of the rats. Ozone therapy improved severe renal insufficiency and tubulointerstitial morphology injury as well as restored Nrf2 activation and inhibited the NF-κB pathway in rats with adenine-induced CKD. Ozone therapy also up-regulated anti-oxidation enzymes (SOD, CAT, and GSH) and down-regulated oxidation products (PCO and MDA), as well as inflammatory cytokines (IL-1β, IL-6, TNF-α, and ICAM-1) in the kidney. These findings indicated that ozone therapy could attenuate tubulointerstitial injury in rats with adenine-induced CKD by mediating Nrf2 and NF-κB.

Kidney and Liver Injuries After Major Burns in Rats Are Prevented by Resolvin D2.

Innate immune dysfunction after major burn injuries increases the susceptibility to organ failure. Lipid mediators of inflammation resolution, e.g., resolvin D2, have been shown recently to restore neutrophil functionality and reduce mortality rate in a rat model of major burn injury. However, the physiological mechanisms responsible for the benefic activity of resolvin D2 are not well understood. Prospective randomized animal investigation. Academic research setting. Wistar male rats. Animals were subjected to a full-thickness burn of 30% total body surface area. Two hours after burn, 25 ng/kg resolvin D2 was administered IV and repeated every day, for 8 days. At day 10 post burn, 2 mg/kg of lipopolysaccharide was administered IV, and the presence of renal and hepatic injuries was evaluated at day 11 post burn by histology, immunohistochemistry, and relevant blood chemistry. In untreated animals, we found significant tissue damage in the kidneys and liver, consistent with acute tubular necrosis and multifocal necrosis, and changes in blood chemistry, reflecting the deterioration of renal and hepatic functions. We detected less tissue damage and significantly lower values of blood urea nitrogen (26.4 ± 2.1 vs 36.0 ± 9.3 mg/dL; p ≤ 0.001), alanine aminotransferase (266.5 ± 295.2 vs 861.8 ± 813.7 U/L; p ≤ 0.01), and total bilirubin (0.13 ± 0.05 vs 0.30 ± 0.14 mg/dL; p ≤ 0.01) in resolvin D2-treated rats than in untreated animals. The mean blood pressure of all animals was above 65 mm Hg, indicating adequate tissue perfusion throughout the experiments. We measured significantly larger amounts of chromatin in the circulation of untreated than of resolvin D2-treated rats (575.1 ± 331.0 vs 264.1 ± 122.4 ng/mL; p ≤ 0.05) and identified neutrophil extracellular traps in kidney and liver tissues from untreated rats, consistent with the tissue damage. Pathologic changes in kidney and liver tissues in a rat model of major burn and endotoxin insults are ameliorated by resolvin D2.

Exposure to Hyperbaric Oxygen Intensified Vancomycin-Induced Nephrotoxicity in Rats.

It has been suggested that oxidative stress is a potential mechanism for vancomycin-induced nephrotoxicity and hyperbaric oxygen therapy (HBO) has been shown to be effective in treating renal toxicity that has been pharmacologically induced in animal models. The aim of this study was to investigate the effect of HBO therapy on vancomycin-induced nephrotoxicity in rats. The study group comprised 36 Sprague Dawley male rats. We treated 30 with 500 mg/kg of intraperitoneal vancomycin once a day for 7 days. Half of these rats received a daily 1-hour treatment with HBO at 2 Atmospheres (ATM) on the same 7 days and formed the HBO+ group. The other 15 subjects received no HBO treatment (HBO- group). The remaining six rats served as the control group, three received HBO treatments alone and no treatment was administered to the other three rats. Laboratory results were obtained on day 8 and the intervention and control groups were compared. Rats in the HBO+ group gained less weight than the HBO- group (11.6 grams vs 22.6 grams; P = 0,008) and had significantly higher serum blood urea nitrogen (99.6 vs 52.6 mg/dL; P<0.001), serum creatinine (0.42 vs 0.16 mg/dL; P = 0.001) and magnesium (3.6 vs 3.1mg/dL; P = 0.014). The vancomycin blood levels were also higher in the HBO+ group (27.8 vs 6.7 μg/mL; P = 0.078). There were no pathological kidney changes in the control group. All the kidneys from the treated groups (vancomycin +HBO and vancomycin HBO-) showed moderate to severe histopathological changes with no statistical significance between them. This study demonstrated that exposure to hyperbaric oxygen intensified vancomycin-induced nephrotoxicity in rats.

&lt;i&gt;Clematis chinensis&lt;/i&gt; Extract Protects against Diabetic Nephropathy in Rats

Purpose: To study the effect of Clematis chinensis extract (CCE) on diabetic nephropathy in rats. Methods: Eight-week old male Wistar rats were injected with streptozotocin to induce diabetes. The effects of CCE(250 or 500 mg/kg) on renal function index, fasting blood glucose (FBG), blood fat, oxidation index, and pathological kidney changes for 3 weeks were compared to those of the positive control drug, captopril. Results: At 12 weeks, CCE(500 mg/kg) treatment had significantly decreased serum blood urea nitrogen (BUN, 12.61 ± 1.42 mmol/L), serum creatinine (SCr, 84.64 ± 6.37 μmol/L), creatinine clearance (CCr, 0.88 ± 0.10 mmol/L), interleukin-6 (IL-6, 297.56 ± 19.62 pg/mL), urinary albumin, urinary albumin excretion rate (UAER, 11.68 ± 0.97 μg/min), kidney hypertrophy index (kidney weight/body weight, 0.58 ± 0.03%) and FBG (11.51 ± 0.96 mmol·L -1 ). It significantly decreased triglyceride (TG, 0.26 ± 0.05 mmol/L), total cholesterol (TC, 1.52 ± 0.06 mmol/L) and low-density lipoprotein-cholesterol (LDL-c, 0.71 ± 0.06 mmol/L) levels and increased high-density lipoprotein-cholesterol (HDL-c, 0.65 ± 0.05 mmol/L). CCE treatment also significantly decreased malondialdehyde (MDA, 16.14 ± 1.24 nmol/mgprot) levels and increased superoxide dismutase (SOD, 95.17 ± 4.06 U/mgprot) and glutathione peroxidase (GSHPx, 154.33 ± 11.76 mmol/L) (both p < 0.05). Finally, CCE reduced the degree of glomerular basement membrane and renal tubular thickening and swelling in diabetic rats. Conclusion: CCE has a significant inhibitory effect on diabetic nephropathy-induced renal injury in rats.

Expression and significance of microRNA-21 in acute kidney injury renal of mice

Objective To investigate the expression and significance of microRNA-21(miR-21) in acute kidney injury mice model at the different time points following ischemic/reperfusion. Methods C57BL/6J mice were divided into 3 major groups: the control group (C group), sham operation group(S group) and ischemia-reperfusion group (IR group). Later 2 groups were divided into 9 sub-groups respectively according to the time following reperfusion.Automatic biochemical analyzer detected serum creatinine (Scr), blood urea nitrogen (BUN) level.HE staining detected renal pathological damage.Renal tubulointerstitial pathological score accessed pathological damage.Real time-PCR tested the expression of miR-21 and mitogen-activated protein kinase kinase 3(MKK3) mRNA in renal respectively.Immunohistochemistry staining tested expression of MKK3. Results IR group's Scr, BUN levels gradually increased following reperfusion, 24 h reached its peak, then gradually declined.The Scr, BUN level had statistically significant difference between IR group and S group at the same time subgroup from 3 h to 168 h following reperfusion(all P<0.01). The change of kidney damage and pathological changes of interstitial and tubular injury score consensus with renal function.miR-21 increased gradually in renal ischemia after reperfusion, 24 h peaked and then stabilized at this high level.miR-21 was positively correlated with pathological tubulointerstitial injury from 0 h to 168 h after reperfusion (r=0.969, P<0.05). IR group's MKK3 mRNA and protein expression rose sharply following ischemia/reperfusion, 24 h peaked, and then gradually decreased.From 3 h to 168 h, the expression of MKK3 mRNA and proteins had significant difference at each same time points subgroups between IR group and S group(all P<0.01). Conclusions miR-21 increases gradually in renal ischemia after reperfusion, 24 h peaked and then stabilized at this high level.miR-21 is positively correlated with pathological tubulointerstitial injury, which may be associated with the negative regulated relationship between miR-21 and MKK3. Key words: microRNA-21; Ischemia-reperfusion injury; Acute kidney injury; Mitogen-activated protein kinase kinase 3

Amelioration of Diabetic Mouse Nephropathy by Catalpol Correlates with Down-Regulation of Grb10 Expression and Activation of Insulin-Like Growth Factor 1 / Insulin-Like Growth Factor 1 Receptor Signaling.

Growth factor receptor-bound protein 10 (Grb10) is an adaptor protein that can negatively regulate the insulin-like growth factor 1 receptor (IGF-1R). The IGF1-1R pathway is critical for cell growth and apoptosis and has been implicated in kidney diseases; however, it is still unknown whether Grb10 expression is up-regulated and plays a role in diabetic nephropathy. Catalpol, a major active ingredient of a traditional Chinese medicine, Rehmannia, has been reported to possess anti-inflammatory and anti-aging activities and then used to treat diabetes. Herein, we aimed to assess the therapeutic effect of catalpol on a mouse model diabetic nephropathy and the potential role of Grb10 in the pathogenesis of this diabetes-associated complication. Our results showed that catalpol treatment improved diabetes-associated impaired renal functions and ameliorated pathological changes in kidneys of diabetic mice. We also found that Grb10 expression was significantly elevated in kidneys of diabetic mice as compared with that in non-diabetic mice, while treatment with catalpol significantly abrogated the elevated Grb10 expression in diabetic kidneys. On the contrary, IGF-1 mRNA levels and IGF-1R phosphorylation were significantly higher in kidneys of catalpol-treated diabetic mice than those in non-treated diabetic mice. Our results suggest that elevated Grb10 expression may play an important role in the pathogenesis of diabetic nephropathy through suppressing IGF-1/IGF-1R signaling pathway, which might be a potential molecular target of catalpol for the treatment of this diabetic complication.

4-HNE expression in diabetic rat kidneys and the protective effects of probucol.

To investigate 4-HNE expression in diabetic rat kidneys and the protective effect of probucol. Diabetic rat models were established. Diabetic rats with successful modeling were randomly divided into the diabetic group (group D) and probucol treated group (group P). Normal rats were put into the control group (group C). Rats in group P were treated with probucol (110mg/kgday), and rats in groups D and C were given equal volume of water instead. Serum creatinine (SCr), urea nitrogen (BUN), triglyceride (TG), total cholesterol (TC), and 24-h urinary protein were measured at the 4th, 8th, and 12th weeks. Periodic acid-schiff (PAS) staining and hematoxylin-eosin (HE) staining were used to evaluate the renal pathological changes. The immunohistochemistry and Western-blot were used to detect 4-HNE expression in renal tissue. The SCr, BUN, TG, TC, and 24-h urinary protein in group D increased in the 4th, 8th, and 12th weeks and were higher than those in group C (P<0.05). The SCr, BUN, TG, TC, and 24-h urinary protein in group P decreased compared to group D (P<0.05). Pathological kidney changes in group D were more serious than those in group P. The level of 4-HNE expression in group D significantly increased at the 4th, 8th, and 12th weeks and were higher than those in group C (P<0.05). In the kidneys treated with probucol, the level of 4-HNE significantly decreased compared to group D (P<0.05). Probucol can protect the diabetic kidney by decreasing 4-HNE expression and lipid peroxidation levels.

Protective effect of luteolin on streptozotocin-induced diabetic renal damage in mice via the regulation of RIP140/NF-кB pathway and insulin signalling pathway

Luteolin (LUT) is one of the most common flavonoids present in various fruits and vegetables. The effects of luteolin (LUT) on streptozotocin (STZ)-induced diabetic renal damage were investigated. LUT was orally administered at 10, 20 mg/kg/day for 4 weeks to streptozotocin-induced diabetic mice. Serum levels of uric acid, creatinine, triacylglycerol, total cholesterol, low density lipoprotein and blood urea nitrogen were measured. Urinary uric acid and creatinine were assayed. Serum insulin level and oral glucose tolerance test (OGTT) were determined. Kidney pathological changes were detected. Receptor-interacting protein 140 (RIP140)/nuclear factor кB (NF-кB) pathway and insulin signalling pathway were detected. LUT restored streptozotocin-induced insulin resistance, dyslipidaemia, hyperuricemia, and renal inflammatory cell infiltration in streptozotocin-induced mice. Furthermore, LUT inhibited RIP140/NF-кB pathway and improved the insulin signalling pathway in streptozotocin-induced renal damage in mice. Thus, the beneficial effect of LUT against diabetic nephropathy (DN) is related to its regulation of RIP140/NF-кB and insulin pathway.

Effects and mechanisms of Rapamycin on renal interstitial fibrosis in rats

Objective To discuss the intervention effects and mechanisms for Rapamycin on renal interstitial fibrosis in rats. Methods A total of 72 Wistar male rats were randomly divided into 3 groups, normal group(n=24), model group(n=24), treatment group(n=24). The model group and treatment group received adenine 200 mg/kg daily, and the treatment group was also given Rapamycin 5 mg/(kg·d) at the 8th day, the normal group was just given the same amount of normal saline for 6 weeks.In the end of the 2nd, 4th and 6th week, 8 rats in each group were sacrificed respectively.The expression of hepatocyte growth factor(HGF), transforming growth factor-β(TGF-β)and neutrophils gelatinases related apolipoprotein(NGAL)in each group were observed.The software of image analysis system was used for semi-quantitative analysis. Results HE and Masson staining results showed that the renal tubular were progressive swelling, and changed with interstitial fibrosis, atrophy and even necrosis in model group from 2 weeks to 6 weeks.The pathological changes of kidney were more ease in the treatment group compared with those in model group.Immunohistochemical staining results showed that HGF expression levels of renal interstitial tissue in model group and treatment group at the 2nd week were significantly higher than those of normal group(P<0.05), and were significantly decreased at the 4th week and 6th week(P<0.05); HGF expression levels of renal interstitial tissue in treatment group were significantly higher than those in model group(P<0.05). NGAL expression levels of renal interstitial tissue in model group and treatment group at the 2nd week were significantly higher than those in normal group(P<0.05), and were significantly decreased at the 4th week and 6th week(P<0.05); NGAL expression levels of renal interstitial tissue in treatment group were significantly higher than those in model group(P<0.05). TGF-β expression levels of renal interstitial tissue in model group and treatment group at the 2nd, 4th, and 6th week were significantly higher than those in normal group(P<0.05), while TGF-β expression levels of renal interstitial tissue in treatment group were significantly lower than those in model group(P<0.05). Conclusion Rapamycin could improve the rat kidney tissue pathology, relieve renal tubular expansion, and slow progression of renal interstitial fibrosis, and has certain protective effect to the kidney. Key words: Rapamycin; Renal interstitial fibrosis; Intervention mechanism

T-5224, a selective inhibitor of c-Fos/activator protein-1, improves survival by inhibiting serum high mobility group box-1 in lethal lipopolysaccharide-induced acute kidney injury model

BackgroundSepsis is a potentially fatal syndrome mediated by an early [e.g., tumor necrosis factor-alpha (TNF-α)] and late [high mobility group box-1 (HMGB-1)] proinflammatory cytokine response to infection. Sepsis-induced acute kidney injury (AKI) is associated with a high mortality. C-Fos/activator protein-1 (AP-1) controls the transactivation of proinflammatory cytokines via AP-1 binding in the promoter region. T-5224 is a de novo small molecule inhibitor of c-Fos/AP-1 that controls gene expression of multiple proinflammatory cytokines. We investigated whether T-5224, a selective inhibitor of c-Fos/AP-1, improves survival in lethal lipopolysaccharide (LPS)-induced AKI by inhibiting early (TNF-α) and late (HMGB-1) proinflammatory cytokine response.MethodsMice were divided into four groups (control, LPS, LPS + T-5224, and T-5224 only). Control mice were administered polyvinylpyrrolidone (PVP) solution orally, immediately after intraperitoneal (i.p.) saline injection. LPS mice were administered PVP solution orally immediately after i.p. LPS (10 mg/kg) injection. LPS + T-5224 mice were administered T-5224 orally (300 mg/kg) immediately after i.p. LPS injection. T-5224 mice were administered T-5224 orally (300 mg/kg) after i.p. saline injection. Serum concentrations of TNF-α, HMBG-1, and interleukin (IL)-10 were measured by enzyme-linked immunosorbent assay (ELISA). Serum blood urea nitrogen (BUN) and creatinine concentrations were commercially analyzed. Finally, histological examination was performed on the kidney.ResultsTreatment with T-5224 decreased serum TNF-α and HMGB-1 levels and increased survival after LPS injection. Furthermore, T-5224 treatment decreased serum BUN and creatinine concentrations but increased serum IL-10 concentration. LPS-induced pathological changes in kidney were attenuated by T-5224 treatment.ConclusionsThese results suggest that T-5224, a selective inhibitor of c-Fos/AP-1, inhibits expression of early and late proinflammatory cytokines, protecting mice from LPS-induced lethality. T-5224 is a potential approach for decreasing lethality in sepsis-induced AKI.

Lipopolysaccharide Induces Chronic Kidney Injury and Fibrosis through Activation of mTOR Signaling in Macrophages

Background: Septic kidney injury is one of the most common complications in critically ill patients with a high risk of developing chronic kidney disease (CKD). Emerging data indicate that mammalian target of rapamyci (mTOR) signaling plays a major role in septic inflammation by regulating the immune response of macrophage. This study was designed to evaluate the role of mTOR signaling in kidney macrophages during endotoxemia-induced chronic kidney injury and subsequent fibrogenesis. Methods: Male C57BL/6 mice were used for all animal studies (n = 9 for each group). Lipopolysaccharide (LPS) was injected intraperitoneally (1 mg/kg) every 2 days to induce persistent endotoxemia. Rapamycin (1 mg/kg·day) was administered to a subgroup of mice 1 day prior to LPS treatment and continued to termination of the experiment. In ex-vivo experiment, RAW264.7 cells were cultured and treated with LPS (2 µg/ml) for 48 h while a subgroup of cells were incubated in the presence of rapamycin (50 nmol) for 2 h. Results: Continuous administration of LPS resulted in progressive macrophage infiltration, tubular injury and collagen deposition in mice kidneys. Rapamycin markedly ameliorated LPS-induced kidney pathological changes. Expression of pS6K was rarely observed in normal kidney macrophages, but significantly increased with time by LPS treatment. In ex-vivo study, LPS induced prominent production of IL-1β and MCP-1 in cultured RAW264.7 cells, which was significantly suppressed by rapamycin. Conclusion: Taken together, our findings show that endotoxemia results in activation of mTOR signaling in macrophages, leading to progressive kidney inflammatory injuries and subsequent fibrosis. Our study may reveal a mechanism involved in the development of sepsis-associated CKD and kidney fibrosis.

Inhibition of calcineurin/NFAT pathway plays an essential role in renoprotective effect of tropisetron in early stage of diabetic nephropathy

Recent studies have shown that calcineurin plays a central role in hypertrophy and extracellular matrix (ECM) accumulation in glomeruli at the early stages of diabetic nephropathy. Tropisetron is an effective antiemetic drug which also can potently inhibit calcineurin. The aim of this study was to investigate whether tropisetron can prevent glomerular hypertrophy and ECM expansion in early diabetic nephropathy. Streptozotocin (STZ)-induced diabetic rats were treated with tropisetron and cyclosporine A, a pharmacological calcineurin inhibitor, and the renal function and the expression of calcineurin and fibronectin were then assessed as well as nuclear localization of nuclear factor of activated T-cell c1 (NFATc1). 2 weeks after diabetes induction, all STZ-treated rats showed hyperglycemia, polyuria, body weight loss and renal dysfunction, as evidenced by increased glomerular filtration rate (GFR), along with a marked pathological changes in kidney. Calcineurin expression was increased in association with increased nuclear localization of the calcineurin substrate NFATc1 and fibronectin expression in glomeruli of diabetic rats. In parallel, the diabetic glomeruli became hypertrophic with an increase in kidney weight. Tropisetron, as potent as cyclosporine A, significantly ameliorated the early nephropathy symptoms, potentially through suppression of calcineurin expression, nuclear localization of NFATc1 and accumulation of fibronectin, and thereby reduced hypertrophy in glomeruli of diabetic rats.In conclusion, our results showed that tropisetron could ameliorate kidney injury in the early stage of diabetic nephropathy in rats. The renoprotective effects of tropisetron can be attributed, at least in part, to the suppression of diabetes-induced increases in calcineurin expression in kidney tissue.

Role of the ER stress in prostaglandin E2/E-prostanoid 2 receptor involved TGF-β1-induced mice mesangial cell injury.

This study aims to investigate the relationship between prostaglandin E2 E-prostanoid 2 receptor (EP2) and Endoplasmic reticulum (ER) stress in transforming growth factor-β1 (TGF-β1)-induced mouse glomerular mesangial cells (MCs) injury. We cultured primary WT, EP2(-/-) MCs (EP2 deleted), and adenovirus-EP2-infected WT MCs (EP2 overexpressed). PCR, Western blot, flow cytometry, and immunohistochemical technique were used in in vitro and in vivo experiments. We found that TGF-β1-induced PGE2 synthesis decreased in EP2-deleted MCs and increased in EP2-overexpressed MCs. EP2 deficiency in these MCs augmented the coupling of TGF-β1 to ER stress-associated proteins [chaperone glucose-regulated protein 78 (GRP78), transient receptor potential channel 1 (TRPC1), and transient receptor potential channel 4 (TRPC4)], and upregulation of EP2 showed no significant change of GRP78, but augmented the expression of TRPC1, while TRPC4 expression was downregulated in comparison to normal MCs. In addition, EP2 deficiency in MCs augmented TGF-β1-induced fibronectin (FN), cyclooxygenase-2 (COX2), and CyclinD1 expression. Silencing of EP2 also strengthened TGF-β1-induced extracellular-signal-regulated kinase 1/2 (ERK1/2) phosphorylation. Flow Cytometry showed that silencing of EP2 significantly promoted the apoptosis of MCs. In contrast, EP2 overexpression reversed the effects of EP2 deficiency. 8weeks after 5/6 nephrectomy (Nx), blood urea nitrogen and creatinine concentrations were significantly increased in EP2(-/-) 5/6Nx mice as compared to those of WT 5/6Nx mice. The pathological changes in kidney of EP2(-/-) mice were markedly aggravated compared with WT mice. Immunohistochemical analysis showed significant augment of TRPC4 and ORP150 in the kidney of EP2(-/-) mice compared with WT mice. Considering all the findings, it is suggested that increased expression of EP2 may prevent TGF-β1-induced MCs damage through ER stress regulatory pathway.

Simiao pill ameliorates renal glomerular injury via increasing Sirt1 expression and suppressing NF-κB/NLRP3 inflammasome activation in high fructose-fed rats

Ethnopharmacological relevanceSimiao pill is one of the most frequently prescriptions in traditional Chinese medicine to treat hyperuricemia and gout. This study was to investigate the protective effects of Simiao pill on renal glomerular injury in a rat model of high fructose intake. Materials and methodsSprague–Dawley male rats were given 10% fructose in drinking water and standard laboratory chow for 4 weeks to induce hyperuricemia and metabolic syndrome. Then fructose-fed animals were randomly divided into four groups receiving water, Simiao pill (78.87 and 157.74mg/kg) and allopurinol (5mg/kg) daily for next 6 weeks, respectively. Serum levels of uric acid, creatinine, triglyceride, total cholesterol, low density lipoprotein, blood urea nitrogen, insulin, as well as urinary albumin were measured. Oral glucose tolerance test (OGTT) was carried out. Kidney pathological changes were detected using periodic-acid schiff-stained (PAS) staining and transmission electron microscopy (TEM) analysis. Glomerular protein levels of nephrin, podocin, CD2-associated protein (CD2AP), interleukin (IL)-1β, sirtuin 1 (Sirt1), nuclear factor kappaB (NF-κB) and pyrin domain containing 3 (NLRP3) inflammasome were measured by Western blot. ResultsSimiao pill effectively restored high fructose-induced hyperuricemia and metabolic syndrome in rats. Simiao pill significantly increased protein levels of nephrin, podocin and CD2AP in renal glomeruli, improved renal inflammatory cell infiltration into interstitium and glomerular injury in high fructose-fed rats with reduction of urine albumin levels. Furthermore, Simiao pill up-regulated Sirt1 protein levels and suppressed NF-κB/NLRP3 inflammasome activation to reduce IL-1β in renal glomeruli of high fructose-fed rats. ConclusionsThe renal protective effects of Simiao pill may be associated with up-regulation of Sirt1 expression and suppression of NF-κB/NLRP3 inflammasome activation to reduce renal glomerular injury in high fructose-fed rats with metabolic syndrome.

Effects of forkhead transcription factor O1 on the expression of type IV collagen and desmin in podocytes of diabetic rats

To study the effects of forkhead transcription factor O1(FoxO1)on the expression of type Ⅳ collagen and desmin in podocytes of diabetic rats. Streptozotocin-induced diabetic rats were divided into three groups: diabetic rats(DM group), rats transfected with blank lentiviral vectors(diabetes mellitus plus LV-pSC-GFP group, LV-NC group), and rats which were transfected with lentiviral vectors carrying constitutively active FoxO1(diabetes mellitus plus LV-FoxO1-AAA group, LV-CA group). Rats which received an injection of diluent buffer served as normal control. At 2, 4, and 8 weeks after transfection, the levels of urine albumin, blood glucose, blood urea nitrogen, and serum creatinine were measured. Realtime PCR and Western blotting were performed to measure the mRNA and protein levels of FoxO1, COL4A3, COL4A5, and desmin in the renal cortex. Moreover, light microscope and electron microscope were used to observe the structural changes in glomerulus and podocytes. Compared with LV-NC and DM group, in LV-CA group, there was a significant increase in the mRNA and protein levels of FoxO1, and a distinct decrease in the levels of urine albumin, blood urea nitrogen and serum creatinine of rats(except at the two-week time point)(all P<0.05), the mRNA and protein levels of COL4A3, COL4A5, and desmin were all decreased(all P<0.05), and pathological changes in kidney were also improved. Upregulating the expression of FoxO1 by transfecting with constructed lentiviral vectors can definitely improve the abnormal expression of type Ⅳ collagen and desmin in podocytes of diabetic rats. (Chin J Endocrinol Metab, 2015, 31: 354-359) Key words: Diabetic nephropathy; Forkhead transcription factor O1; Podocytes; Type Ⅳ collagen; Desmin