ABSTRACT
Objective To investigate the protective effect of human umbilical cord mesenchymal stem cell-derived exosome (hucMSC-Exo) on renal ischemia-reperfusion injury (IRI), and to clarify the critical role and regulating mechanism of transient receptor potential canonical (TRPC) 6/poly adenosine-diphosphate-ribose polymerase (PARP) 1 signaling pathway during this process. Methods The hucMSC-Exo was extracted by ultracentrifugation, and identified by transmission electron microscope (TEM), nanoparticle tracing analysis and Western blot. SD rats were randomly divided into the sham operation group (group S), sham operation+TRPC6 inhibitor SKF96365 group (group SS), renal IRI group (group IRI), exosome treatment group (group EXO) and exosome +TRPC6 inhibitor SKF96365 group (group ES), with 6 rats in each group. Serum creatinine and blood urea nitrogen levels were detected. Pathological changes of renal tissues were observed by hematoxylin-eosin (HE) staining and Paller score was calculated. The expression levels of key molecules of necroptosis in rat renal tissues, including receptor-interacting protein kinase (RIPK)1, RIPK3 and mixed-lineage kinase domain-like protein (MLKL), TRPC6 and PARP1, were detected by Western blot. Results Typical saucer-like structure was observed under TEM. Nanoparticle tracing analysis showed that the average diameter of the extracted substance was 125.9 nm. Western blot revealed that the surface markers of CD9, CD63 and CD81 were positively expressed, confirmed that the extracted substance was exosome. Compared with group S, the serum creatinine and blood urea nitrogen levels were up-regulated, the pathological damage of renal tissues was worsened, Paller score was elevated, the relative expression levels of TRPC6 and PARP1 proteins were down-regulated, and the relative expression levels of RIPK1, RIPK3 and MLKL proteins were up-regulated in group IRI (all P < 0.05). Compared with group IRI, the serum creatinine and blood urea nitrogen levels were down-regulated, the pathological damage of renal tissues was mitigated, Paller score was decreased, the relative expression levels of TRPC6 and PARP1 proteins were up-regulated, and the relative expression levels of RIPK1, RIPK3 and MLKL proteins were down-regulated in group EXO (all P < 0.05). Compared with group EXO, the serum creatinine and blood urea nitrogen levels were up-regulated, the pathological damage of renal tissues was aggravated, Paller score was increased, the relative expression levels of TRPC6 and PARP1 proteins were down-regulated, and the relative expression levels of RIPK1, RIPK3 and MLKL proteins were up-regulated in group ES (all P < 0.05). Conclusions hucMSC-Exo may alleviate the necroptosis induced by renal IRI in rat models, which is related to the activation of TRPC6/PARP1 signaling pathway.
ABSTRACT
Ischemia-reperfusion injury (IRI) refers to the reperfusion injury caused by the recovery of blood supply of ischemic tissues or organs, which commonly occurs in organ transplantation and other surgical procedures. IRI may cause a series of severe clinical issues, such as delayed graft function, acute kidney injury, myocardial infarction, ischemic stroke and circulatory arrest, etc. These events yield high incidence and fatality. At present, no effective solution has been available. Transient receptor potential canonical 6 (TRPC6), a member of Ca2+ channel family, is highly expressed in multiple types of cells. It may adjust many physiological functions by regulating intracellular Ca2+ concentration, which has become an important target for developing therapeutic drugs for multiple diseases. In this article, research progresses on the introduction and function of TRPC6, the association between TRPC6 and IRI and the therapeutic prospect of TRPC6 targeted drugs in IRI were reviewed, aiming to provide novel insights into the prevention and treatment of IRI during organ transplantation
ABSTRACT
Objective To evaluate the effect of intrathecal dexmedetomidine on expression of sub-stance P (SP) and c-fos in the spinal dorsal horns of rats with visceral pain. Methods Thirty-two clean-grade healthy adult male Sprague-Dawley rats, weighing 250-300 g, were divided into 4 groups ( n=8 each) using a random number table method: control group (C group), visceral pain group (VP group), dexmedetomidine group (D group) and dexmedetomidine plus atipamezole group (DA group). VP, D and DA groups received intraperitoneal injection of 0. 9％ acetic acid 10 ml∕kg to establish the model of visceral pain, while group C received the equal volume of normal saline instead. At 10 min before the model was es-tablished, dexmedetomidine 20 μl (1μg∕kg) and dexmedetomidine 1μg∕kg plus atipamezole 1μg∕kg (20μl) were intrathecally injected in D and DA groups, respectively, and the equal volume of normal saline 20μl was given instead in C and VP groups. Visceral pain index ( VPI) was recorded at 1 h after intraperito-neal injection, and then rats were sacrificed, and the dorsal horns of the spinal cord ( L4-6 ) were removed for determination of the expression of SP and c-fos by immunohistochemistry. Results Compared with group C, VPI was significantly increased, and the expression of SP and c-fos was up-regulated in VP, D and DA groups (P<0. 05). Compared with group VP, VPI was significantly decreased, and the expression of SP and c-fos was down-regulated in D and DA groups (P<0. 05). Compared with group D, VPI was signifi-cantly increased, and the expression of SP and c-fos was up-regulated in group DA ( P<0. 05) . Conclusion Intrathecal dexmedetomidine reduces the visceral pain through inhibiting the expression of SP and c-fos in the spinal dorsal horns, which is related to the α2-adrenergic receptor in spinal dorsal horns of rats.
ABSTRACT
Objective To evaluate the effect of dexmedetomidine on lipid peroxidation during lung ischemia-reperfusion (I/R) in rats.Methods Fifty-four pathogen-free healthy male Wistar rats,weighing 250-350 g,were randomly divided into 3 groups (n=18 each) using a random number table:sham operation group (S group),I/R group,and dexmedetomidine group (Dex group).In group Dex,dexmedetomidine 5 μg/kg was injected via the caudal vein once a day for 2 consecutive days.The equal volume of normal saline was given in S and I/R groups.At 30 min after administration on 2nd day,lung I/R was produced by clamping the left hilum of lung for 45 min followed by 120 min of reperfusion in I/R and Dex groups.At 45 min of ischemia,and 60 and 120 min of reperfusion,6 rats selected from each group were sacrificed,and the left lungs were removed for examination of the pathological changes and for determination of wet/dry lung weight ratio (W/D ratio),malondialdehyde (MDA) content and superoxide dismutase (SOD) activity.Results Compared with S group,the SOD activity was significantly decreased,and the MDA content and W/D ratio were significantly increased at 60 and 120 min of reperfusion in I/R and Dex groups (P＜0.05).Compared with I/R group,the SOD activity was significantly increased,and the MDA content and W/D ratio were significantly decreased at 60 and 120 min of reperfusion in Dex group (P＜0.05).The pathological changes of lungs were significantly attenuated in Dex group as compared with I/R group.Conclusion Dexmedetomidine mitigates lung I/R injury through inhibiting lipid peroxidation in rats.
ABSTRACT
Objective To evaluate the effect of sinomenine on apoptosis in renal tubular epithelial cells of rats subjected to renal ischemia-reperfusion (I/R), and the relationship with C-Jun N-terminal kinase (JNK) signaling pathway.Methods Fifty-four male Wistar rats, aged 6-8 weeks, weighing 180-220 g, were randomly divided into 3 groups (n =18 each) using a random number table: sham operation group (group S), I/R group and sinomenine group (group SIN).Renal ischemia was induced by occlusion of the left renal pedicle for 45 min followed by reperfusion, and the right kidney was removed immediately after onset of reperfusion in anesthetized rats in I/R and SIN groups.In group SIN, sinomenine 60 mg/kg was injected intraperitoneally at 30 min before reperfusion, while the equal volume of normal saline was given instead of sinomenine at the same time point in S and I/R groups.Six animals in each group were selected at 0.5, 6 and 24 h of reperfusion, blood samples were collected by cardiac puncture for determination of serum creatinine (Cr) and blood urea nitrogen (BUN) concentrations.Immediately after blood sampling, the left kidney was removed for examination of pathological changes in renal tissues (with light microscopes) and for determination of phosphorylated JNK (p-JNK) and caspase-3 expression (by immune-histochemistry) and apoptosis in renal tubular epithelial cells (by TUNEL).The apoptotic rate was calculated.Results Compared with group S, the serum Cr and BUN concentrations were significantly increased, the expression of p-JNK and caspase-3 was up-regulated, and the apoptotic rate was increased in I/R and SIN groups.Compared with group I/R, the serum Cr and BUN concentrations were significantly decreased, the expression of p-JNK and caspase-3 was down-regulated, and the apoptotic rate was decreased in group SIN.The microscopic examination showed that the pathological changes of kidney were significantly attenuated in group SIN compared with group I/R.Conclusion The mechanism by which sinomenine attenuates renal I/R injury is related to inhibited activation of p-JNK signaling pathway and reduced apoptosis in renal tubular epithelial cells of rats.
ABSTRACT
Objective To investigate the effect of sinomenine on the levels of nuclear factor kappa B (NF-κB) and inducible nitric oxide synthase (iNOS) during renal ischemia-reperfusion (I/R) in rats.Methods Seventy-two healthy male Wistar rats, aged 6-9 weeks, weighing 180-220 g, were randomly assigned into 4 groups (n =18 each) using a random number table: control group (group C), sinomenine group (group SIN), group I/R, and sinomenine+I/R group (group SIN+I/R).The animals were anesthetized with 10％ chloral hydrate 350 mg/kg.The left renal pedicles were clamped with atraumatic microclips for 45 min followed by reperfusion, and the right kidney was removed immediately after onset of reperfusion to establish the model of renal I/R injury.Sinomenine 60 mg/kg was injected intraperitoneally at 30 min before reperfusion in group SIN +I/R, and at the corresponding time point in group SIN.At 6, 8 and 12 h of reperfusion, the blood samples were drawn by cardiac puncture for measurement of serum creatinine (Cr) and blood urea nitrogen (BUN) concentrations.The left renal specimens were obtained for examination of pathological changes (with light microscopes) and for determination of the rate of NF-κB-positive cells and iNOS expression in renal tissues (by immunohistochemistry).Results Compared with group C, the concentrations of serum Cr and BUN, and rate of NF-κB-positive cells were significantly increased, and the expression of iNOS was up-regulated in I/R and SIN+I/R groups, and no significant change was found in the parameters mentioned above in group SIN.Compared with group I/R, the concentrations of serum Cr and BUN, and rate of NF-κB-positive cells were significantly decreased, and the expression of iNOS was down-regulated in group SIN+I/R.The microscopic examination showed that the pathological changes of kidney were significantly attenuated in group SIN+I/R compared with group I/R.Conclusion The mechanism by which sinomenine attenuates renal I/R injury is related to inhibited activity of NF-κB and down-regulated expression of iNOS in rats.
ABSTRACT
Objective To evaluate the effects of sinomenine on the expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) during renal ischemia-reperfusion (I/ R) in rats.Methods Fifty-four male Wistar rats, weighing 180-220 g, were randomly divided into 3 groups (n=18 each) using a random number table: sham operation group (group S) , group I/R and sinomenine group (group SIN).Renal I/R was induced by clamping the left renal pedicle for 45 min followed by reperfusion in I/R and SIN groups.In group S, the bilateral renal pedicels were only exposed.Sinomenine 60 mg/kg was intraperitoneally injected at 30 min before reperfusion in group SIN, while the equal volume of normal saline was given in group S and group I/R.At 6, 12 and 24 h (T1-3) of reperfusion, 6 rats from each group were chosen, and blood samples were drawn from the hearts for determination of the serum creatinine (Cr) and blood urea nitrogen (BUN) concentrations.The animals were then sacrificed, and the left kidney was removed and embedded into a paraffin block for determination of the expression of HIF-1α and VEGF in the renal tissues (by immuno-histochemistry).Results Compared with group S, the serum Cr and BUN concentrations were significantly increased at T1-3 , and the expression of HIF-1α was significantly up-regulated at T2,3 in group I/R and group SIN, and the expression of VEGF was significantly upregulated at T2,3in group I/R, and at T1-3 in group SIN.Compared with group I/R, the serum Cr concentration at T1-3 and serum BUN concentration at T2,3 were significantly decreased and the expression of HIF-1α at T2,3and VEGF at T1-3was significantly up-regulated in group SIN.Conclusion The mechanism by which sinomenine attenuates renal I/R injury is related to up-regulation of the expression of HIF-1α and VEGF in the renal tissues of rats.
ABSTRACT
Objective To evaluate the effect of lappaconitine on renal ischemia-reperfusion (I/R) injury in mice.Methods Thirty-six male Wistar rats,weighing 180-220 g,were randomly divided into 3 groups (n=12 each) using a random number table:sham operation group (group S),group I/R and lappaconitine group (group LA).Renal I/R was induced by occlusion of the left renal pedicle for 45 min with atraumatic microclips followed by reperfusion,and the right kidney was removed after atraumatic microclips were released.At 30 min before reperfusion,lappaconitine 4 mg/kg was injected intraperitoneally in group LA,and normal saline 2 ml was given in S and I/R groups.In group S,the left renal pedicle was only isolated.At 5 and 24 h of reperfusion,blood samples were taken from the inferior vena cava for determination of serum creatinine (Cr) and blood urea nitrogen (BUN) concentrations,and kidney specimens were obtained for histopathologic examination (with light microscope) and for determination of the expression of cyclooxygenase-2 (COX-2) and matrix metalloproteinase-2 (MMP-2) in renal tissues (by immunohistochemistry).Results Compared with group S,the serum Cr and BUN concentrations were significantly increased,and the expression of COX-2 and MMP-2 in renal tissues was up-regulated at 5 and 24 h of reperfusion in I/R and LA groups.Compared with group I/R,the serum Cr and BUN concentrations were significantly decreased,the expression of COX-2 and MMP-2 in renal tissues was down-regulated at 5 and 24 h of reperfusion and histopathologic changes were reduced in group LA.Conclusion Lappaconitine can attenuate renal I/R injury through inhibiting the expression of COX-2 and MMP-2 in rats.
ABSTRACT
Objective To evaluate the effects of dexmedetomidine on lung ischemia-reperfusion (I/R) injury in rats.Methods Ninety-six healthy SPF male Wistar rats,weighing 250-350 g,aged 8-12 weeks,were randomly divided into 4 groups (n =24 each):sham operation group (S group),I/R group,low dose dexmedetomidine group (DL group) and high dose dexmedetomidine group (DH group).In DL and DH groups,dexmedetomidine 100 and 500 μg· kg-1 · d-1 were injected intraperitoneally once a day for 2 consecutive days,while the equal volume of normal saline was given in S and I/R groups.Lung·I/R was induced by clamping the left hilum of lung for 45 min followed by reperfusion at 30 min after administration on 2nd day.At 45 min of ischemia,and 60 and 120 min of reperfusion,6 rats were sacrificed,and lungswere removed for determination of TNF-α (tumor necrosis factor-a) content and myeloperoxidase (MPO) activity in lung tissues.The percentage of damaged alveolar in lung tissues was detected at 120 min of reperfusion.Another 6 rats were lavaged and the broncho-alveolar lavage fluid (BALF) was colleted for determination of the total protein concentrations.Results Compared with S group,the TNF-α content,MPO activity,percentage of damaged alveolar,and total protein concentrations in BALF were significantly increased in I/R,DL and DH groups.Compared with I/R group,the TNF-α content,MPO activity,percentage of damaged alveolar,and total protein concentrations in BALF were significantly decreased in DL and DH groups.Conclusion Dexmedetomidine can alleviate the lung I/R injury in rats,and the mechanism is related to inhibiton of the inflammatory responses.