AIM: To evaluate preventative effects of ischemic preconditioning(IP) in a rat model of intestinal injury induced by ischemia-reperfusion(IR).METHODS: Male Sprague-Dawley rats(250-300 g) were fasted for 24 h with free...AIM: To evaluate preventative effects of ischemic preconditioning(IP) in a rat model of intestinal injury induced by ischemia-reperfusion(IR).METHODS: Male Sprague-Dawley rats(250-300 g) were fasted for 24 h with free access to water prior to the operation.Eighteen rats were randomly divided into three experimental groups: S group(n = 6),rats were subjected to isolation of the superior mesenteric artery(SMA) for 40 min,then the abdomen was closed; IRgroup(n = 6),rats were subjected to clamping the SMA 40 min,and the abdomen was closed followed by a 4-h reperfusion; IP group(n = 6) rats underwent three cycles of 5 min ischemia and 5 min reperfusion,then clamping of the SMA for 40 min,then the abdomen was closed and a 4-h reperfusion followed.All animals were euthanized by barbiturate overdose(150 mg/kg pentobarbital sodium,i.v.) for tissue collection,and the SMA was isolated via median abdominal incision.Intestinal histologic injury was observed.Malondialdehyde(MDA),myeloperoxidase(MPO) and tumor necrosis factor(TNF)-a concentrations in intestinal tissue were measured.Intercellular adhesion molecule(ICAM)-1 and vascular cell adhesion molecule(VCAM)-1 expression,as well as nuclear factor(NF)-κB activity and expression in intestinal tissue were also determined.RESULTS: Compared with the IR group,IP reduced IR-induced histologic injury of the intestine in rats(2.00 ± 0.71 vs 3.60 ± 0.84,P < 0.05).IP significantly inhibited the increase in MDA content(5.6 ± 0.15 μmol/L vs 6.84 ± 0.18 μmol/L,P < 0.01),MPO activity(0.13 ± 0.01 U/L vs 0.24 ± 0.01 U/L,P < 0.01),and TNF-a levels(7.79 ± 2.35 pg/m L vs 10.87 ± 2.48 pg/m L,P < 0.05) in the intestinal tissue of rats.IP also markedly ameliorated the increase in ICAM-1(204.67 ± 53.27 vs 353.33 ± 45.19,P < 0.05) and VCAM-1(256.67 ± 58.59 vs 377.33 ± 41.42,P < 0.05) protein expression in the intestinal tissues.Additionally,IP remarkably decreased NF-κB activity(0.48 ± 0.16 vs 0.76 ± 0.22,P < 0.05) and protein expression(320.23 ± 38.16 vs 520.76 ± 40.53,P < 0.01) in rat intestinal tissue.CONCLUSION: IP may protect against IR-induced intestinal injury by attenuation of the neutrophilendothelial adhesion cascade via reducing ICAM-1 and VCAM-1 expression and TNF-a-induced NF-κB signaling pathway activity.展开更多
Sodium humate(HA-Na) has been topically used as a wound healing and anti-inflammatory agent in folk medicine. In the present study, HA-Na was investigated for cutaneous wound healing in Sprague–Dawley rats. HA-Na sol...Sodium humate(HA-Na) has been topically used as a wound healing and anti-inflammatory agent in folk medicine. In the present study, HA-Na was investigated for cutaneous wound healing in Sprague–Dawley rats. HA-Na solution(1.0%, w/v) was topically administered to rats undergoing excision wound models. Healing was assessed with a recombinant bovine basic fibroblast growth factor for external use as positive control. Wound healing rates were calculated on Day 3, 6, 9, 14 and 21 after injury, and tissues were also harvested after the same intervals for histological analysis. In addition, tissue hydroxyproline levels were measured. Furthermore, m RNA levels and protein expressions of transforming growth factor-β1, 2, 3(TGF-β1, 2, 3) were determined by RT-PCR and western blot. Protein expression levels of Smad-2,-3,-4 and-7 were also detected by western blot. Our study demonstrates that HA-Na has the capacity to promote wound healing in rats via accelerated wound contraction and increased hydroxyproline content. More importantly, these wound healing effects of HA-Na might be mediated through the TGF-β/Smad signaling pathway. HA-Na may be an effective agent for enhanced wound healing.展开更多
基金Supported by Grants from the Fundamental Research Funds for the Central Universities,No.2013JDHZ08Personnel training Specialized Research Fundation of The Second Affiliated Hospital of Xi’an Jiaotong University of China,No.RC(GG)201404
文摘AIM: To evaluate preventative effects of ischemic preconditioning(IP) in a rat model of intestinal injury induced by ischemia-reperfusion(IR).METHODS: Male Sprague-Dawley rats(250-300 g) were fasted for 24 h with free access to water prior to the operation.Eighteen rats were randomly divided into three experimental groups: S group(n = 6),rats were subjected to isolation of the superior mesenteric artery(SMA) for 40 min,then the abdomen was closed; IRgroup(n = 6),rats were subjected to clamping the SMA 40 min,and the abdomen was closed followed by a 4-h reperfusion; IP group(n = 6) rats underwent three cycles of 5 min ischemia and 5 min reperfusion,then clamping of the SMA for 40 min,then the abdomen was closed and a 4-h reperfusion followed.All animals were euthanized by barbiturate overdose(150 mg/kg pentobarbital sodium,i.v.) for tissue collection,and the SMA was isolated via median abdominal incision.Intestinal histologic injury was observed.Malondialdehyde(MDA),myeloperoxidase(MPO) and tumor necrosis factor(TNF)-a concentrations in intestinal tissue were measured.Intercellular adhesion molecule(ICAM)-1 and vascular cell adhesion molecule(VCAM)-1 expression,as well as nuclear factor(NF)-κB activity and expression in intestinal tissue were also determined.RESULTS: Compared with the IR group,IP reduced IR-induced histologic injury of the intestine in rats(2.00 ± 0.71 vs 3.60 ± 0.84,P < 0.05).IP significantly inhibited the increase in MDA content(5.6 ± 0.15 μmol/L vs 6.84 ± 0.18 μmol/L,P < 0.01),MPO activity(0.13 ± 0.01 U/L vs 0.24 ± 0.01 U/L,P < 0.01),and TNF-a levels(7.79 ± 2.35 pg/m L vs 10.87 ± 2.48 pg/m L,P < 0.05) in the intestinal tissue of rats.IP also markedly ameliorated the increase in ICAM-1(204.67 ± 53.27 vs 353.33 ± 45.19,P < 0.05) and VCAM-1(256.67 ± 58.59 vs 377.33 ± 41.42,P < 0.05) protein expression in the intestinal tissues.Additionally,IP remarkably decreased NF-κB activity(0.48 ± 0.16 vs 0.76 ± 0.22,P < 0.05) and protein expression(320.23 ± 38.16 vs 520.76 ± 40.53,P < 0.01) in rat intestinal tissue.CONCLUSION: IP may protect against IR-induced intestinal injury by attenuation of the neutrophilendothelial adhesion cascade via reducing ICAM-1 and VCAM-1 expression and TNF-a-induced NF-κB signaling pathway activity.
基金financially supported by Innovation Plan Project of Science and Technology of Shaanxi Province (2013KTCQ03-13)
文摘Sodium humate(HA-Na) has been topically used as a wound healing and anti-inflammatory agent in folk medicine. In the present study, HA-Na was investigated for cutaneous wound healing in Sprague–Dawley rats. HA-Na solution(1.0%, w/v) was topically administered to rats undergoing excision wound models. Healing was assessed with a recombinant bovine basic fibroblast growth factor for external use as positive control. Wound healing rates were calculated on Day 3, 6, 9, 14 and 21 after injury, and tissues were also harvested after the same intervals for histological analysis. In addition, tissue hydroxyproline levels were measured. Furthermore, m RNA levels and protein expressions of transforming growth factor-β1, 2, 3(TGF-β1, 2, 3) were determined by RT-PCR and western blot. Protein expression levels of Smad-2,-3,-4 and-7 were also detected by western blot. Our study demonstrates that HA-Na has the capacity to promote wound healing in rats via accelerated wound contraction and increased hydroxyproline content. More importantly, these wound healing effects of HA-Na might be mediated through the TGF-β/Smad signaling pathway. HA-Na may be an effective agent for enhanced wound healing.