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Inhibition of apoptosis by flaxseed in a mouse model of lung ischemia reperfusion injury
S24
Surgical Forum Abstracts
apoptotic cells by 93% in treated ischemic muscle versus ischemic controls (p⬍0.001). CONCLUSIONS: These data suggest that H2S exposure significantly mitigates ischemia-reperfusion injury without direct cellular toxicity in our target range, giving this molecule significant therapeutic potential as a cytoprotectant in free tissue transfer and other conditions associated with ischemic conditions.
Inhibition of apoptosis by flaxseed in a mouse model of lung ischemia reperfusion injury M Jawad Latif MD, Xiaogjui Li PhD, John Afthinos MD, Agnes Colanta MD, Jasminka Balderacchi MD, George J Todd MD, Scott Belsley MD, Cliff P Connery MD, Melpo Christofidou PhD, Faiz Y Bhora MD St Luke’s Roosevelt Hospital Center, Columbia University, New York, NY INTRODUCTION: Flaxseed has known anti-inflammatory and antioxidant properties against lung ischemia/reperfusion (I/R) injury as recently reported by others and us. Our aim was to study if this protective effect of flaxseed is mediated by the inhibition of apoptosis. METHODS: We first established that mouse blood flaxseed lignin levels plateau at 2 weeks. C57BL/6J mice were fed either 0% flaxseed diet (control group, n⫽6) or 10% flaxseed diet (treatment group, n⫽9) for two weeks. After induction of anesthesia and tracheostomy, a ventilator was used to maintain adequate minute ventilation. A left thoracotomy was performed and a microvascular clamp used to occlude the left hilum. After 60 minutes, the clamp was removed and the left lung was reperfused for 3 hours. The animals were euthanized and lung specimens preserved for tissue processing. Apoptosis was detected using (1) Western-blot analysis for Caspase-3 (a key mediator of apoptosis in mammalian cells) and (2) TUNEL assay (in-situ nick-end DNA labeling specific for apoptosis). Histologic evaluation was performed by two blinded pathologists. RESULTS: Western-blot analysis for Caspase-3 was positive in the control group and negative in the flax treated group. TUNEL staining showed significantly increased apoptosis in the control group (72.17⫹ 27.51 cells/hpf ) as compared to the flax treated group (7.17⫹ 3.19 cells/hpf ), p ⬍ 0.05. CONCLUSIONS: The recently reported protective effect of flaxseed in lung I/R injury may in part be mediated by the inhibition of apoptosis. Further studies are needed to elucidate the molecular pathways involved in the down-regulation of apoptosis by flaxseed.
Manganese superoxide dismutase chemoprevention in a murine hepatitis associated injury model Nathaniel Peter Reuter MD, Robert C G Martin MD, FACS, Yan Li PhD University of Louisville, Louisville, KY INTRODUCTION: Oxidative stress plays an integral role in progressive parenchymal liver injury associated with viral hepatitis, alcoholic liver disease, and non-alcoholic steatohepatitis. Concanavalin A
J Am Coll Surg
(Con A) induces oxidative stress and T-cell inflammatory infiltration. The mitochondrial form of superoxide dismutase, manganese surperoxide dismutase (MnSOD) is an antioxidant that can prevent cell death from oxidative injury. The role MnSOD plays in the protection against hepatic injury is largely unknown. We test the hypothesis that Con A induced hepatitis and cell death can be prevented by the administration of the MnSOD mimetic MnTABP. METHODS: Male C57 mice were divided into 3 groups. Group 1 was pretreated with i.p. MnTABP at 10mg/kg for 2 days and then with i.p. Con A 15mg/kg; group 2 was pretreated with i.p. saline for 2 days and then with i.p. Con A 15mg/kg; group 3 was the control treated with i.p. saline for 3 days. Twelve hours after the administration of Con A, the mice were euthanized and the hepatic tissue was evaluated for histology, apoptosis, lipid peroxidation, and MnSOD enzymatic activity. RESULTS: Con A treated mice had extensive hepatic apoptosis and necrosis with a significant increase in apoptosis and lipid peroxidation and decreased MnSOD enzymatic activity. Pretreatment with MnTABP significantly attenuated all of the above responses. Apoptosis, Lipid Peroxidation, and MnSOD Activity in Hepatic Tissue Treated with Con A and MnSOD Supplementation Control
Con A
MnTABP and Con A
Index of apoptosis (%) 0.29 ⫾ 0.13 10.31 ⫾ 0.91 3.60 ⫾ 0.73 Lipid Peroxidation 2.41 ⫾ 0.06 8.22 ⫾ 0.70 3.76 ⫾ 0.18 (nmol/ml) MnSOD activity (%) 0.54 ⫾ 0.004 0.26 ⫾ 0.04 0.58 ⫾ 0.02 CONCLUSIONS: MnTABP protected hepatocytes from Con A induced hepatic injury. The protective effect of MnSOD supplementation against Con A induced hepatitis could be through its antioxidative properties. Naturally occurring agents that lead to increased MnSOD activity may prevent the progression of hepatic disease.
Hydrogen sulfide significantly mitigates cellular injury in intestinal ischemia Sunil P Singh BA, Daniel C Rafii BA, David C Lyden MD, PhD, Jason A Spector MD Weill Cornell Medical College, New York, NY INTRODUCTION: Because of the extremely high metabolic requirements of intestinal tissue, free jejunal transfers are extremely vulnerable to ischemic injury, making expedient revascularization essential. Even transient ischemic damage can delay recovery and function. Hydrogen sulfide (H2S), though traditionally considered toxic, has recently been recognized as an endogenous signaling molecule with potential as a cytoprotectant. METHODS: Twelve 8 week old C57/b6 male mice were exposed to either a mixture of H2S (150ppm) balanced with room air for 30 minutes (6 animals) or room air alone for 30 minutes (6 animals). Ischemia was induced by ligation of the jejunal vascular pedicle and intestinal tissue was harvested after 15 minutes, 2 and 4 hours of ischemia time. Sections were stained with hematoxylin & eosin
Surgical Forum Abstracts
apoptotic cells by 93% in treated ischemic muscle versus ischemic controls (p⬍0.001). CONCLUSIONS: These data suggest that H2S exposure significantly mitigates ischemia-reperfusion injury without direct cellular toxicity in our target range, giving this molecule significant therapeutic potential as a cytoprotectant in free tissue transfer and other conditions associated with ischemic conditions.
Inhibition of apoptosis by flaxseed in a mouse model of lung ischemia reperfusion injury M Jawad Latif MD, Xiaogjui Li PhD, John Afthinos MD, Agnes Colanta MD, Jasminka Balderacchi MD, George J Todd MD, Scott Belsley MD, Cliff P Connery MD, Melpo Christofidou PhD, Faiz Y Bhora MD St Luke’s Roosevelt Hospital Center, Columbia University, New York, NY INTRODUCTION: Flaxseed has known anti-inflammatory and antioxidant properties against lung ischemia/reperfusion (I/R) injury as recently reported by others and us. Our aim was to study if this protective effect of flaxseed is mediated by the inhibition of apoptosis. METHODS: We first established that mouse blood flaxseed lignin levels plateau at 2 weeks. C57BL/6J mice were fed either 0% flaxseed diet (control group, n⫽6) or 10% flaxseed diet (treatment group, n⫽9) for two weeks. After induction of anesthesia and tracheostomy, a ventilator was used to maintain adequate minute ventilation. A left thoracotomy was performed and a microvascular clamp used to occlude the left hilum. After 60 minutes, the clamp was removed and the left lung was reperfused for 3 hours. The animals were euthanized and lung specimens preserved for tissue processing. Apoptosis was detected using (1) Western-blot analysis for Caspase-3 (a key mediator of apoptosis in mammalian cells) and (2) TUNEL assay (in-situ nick-end DNA labeling specific for apoptosis). Histologic evaluation was performed by two blinded pathologists. RESULTS: Western-blot analysis for Caspase-3 was positive in the control group and negative in the flax treated group. TUNEL staining showed significantly increased apoptosis in the control group (72.17⫹ 27.51 cells/hpf ) as compared to the flax treated group (7.17⫹ 3.19 cells/hpf ), p ⬍ 0.05. CONCLUSIONS: The recently reported protective effect of flaxseed in lung I/R injury may in part be mediated by the inhibition of apoptosis. Further studies are needed to elucidate the molecular pathways involved in the down-regulation of apoptosis by flaxseed.
Manganese superoxide dismutase chemoprevention in a murine hepatitis associated injury model Nathaniel Peter Reuter MD, Robert C G Martin MD, FACS, Yan Li PhD University of Louisville, Louisville, KY INTRODUCTION: Oxidative stress plays an integral role in progressive parenchymal liver injury associated with viral hepatitis, alcoholic liver disease, and non-alcoholic steatohepatitis. Concanavalin A
J Am Coll Surg
(Con A) induces oxidative stress and T-cell inflammatory infiltration. The mitochondrial form of superoxide dismutase, manganese surperoxide dismutase (MnSOD) is an antioxidant that can prevent cell death from oxidative injury. The role MnSOD plays in the protection against hepatic injury is largely unknown. We test the hypothesis that Con A induced hepatitis and cell death can be prevented by the administration of the MnSOD mimetic MnTABP. METHODS: Male C57 mice were divided into 3 groups. Group 1 was pretreated with i.p. MnTABP at 10mg/kg for 2 days and then with i.p. Con A 15mg/kg; group 2 was pretreated with i.p. saline for 2 days and then with i.p. Con A 15mg/kg; group 3 was the control treated with i.p. saline for 3 days. Twelve hours after the administration of Con A, the mice were euthanized and the hepatic tissue was evaluated for histology, apoptosis, lipid peroxidation, and MnSOD enzymatic activity. RESULTS: Con A treated mice had extensive hepatic apoptosis and necrosis with a significant increase in apoptosis and lipid peroxidation and decreased MnSOD enzymatic activity. Pretreatment with MnTABP significantly attenuated all of the above responses. Apoptosis, Lipid Peroxidation, and MnSOD Activity in Hepatic Tissue Treated with Con A and MnSOD Supplementation Control
Con A
MnTABP and Con A
Index of apoptosis (%) 0.29 ⫾ 0.13 10.31 ⫾ 0.91 3.60 ⫾ 0.73 Lipid Peroxidation 2.41 ⫾ 0.06 8.22 ⫾ 0.70 3.76 ⫾ 0.18 (nmol/ml) MnSOD activity (%) 0.54 ⫾ 0.004 0.26 ⫾ 0.04 0.58 ⫾ 0.02 CONCLUSIONS: MnTABP protected hepatocytes from Con A induced hepatic injury. The protective effect of MnSOD supplementation against Con A induced hepatitis could be through its antioxidative properties. Naturally occurring agents that lead to increased MnSOD activity may prevent the progression of hepatic disease.
Hydrogen sulfide significantly mitigates cellular injury in intestinal ischemia Sunil P Singh BA, Daniel C Rafii BA, David C Lyden MD, PhD, Jason A Spector MD Weill Cornell Medical College, New York, NY INTRODUCTION: Because of the extremely high metabolic requirements of intestinal tissue, free jejunal transfers are extremely vulnerable to ischemic injury, making expedient revascularization essential. Even transient ischemic damage can delay recovery and function. Hydrogen sulfide (H2S), though traditionally considered toxic, has recently been recognized as an endogenous signaling molecule with potential as a cytoprotectant. METHODS: Twelve 8 week old C57/b6 male mice were exposed to either a mixture of H2S (150ppm) balanced with room air for 30 minutes (6 animals) or room air alone for 30 minutes (6 animals). Ischemia was induced by ligation of the jejunal vascular pedicle and intestinal tissue was harvested after 15 minutes, 2 and 4 hours of ischemia time. Sections were stained with hematoxylin & eosin