thymosin-beta(4) and Reperfusion-Injury

The aim of the present study was to investigate the protective effects of thymosin β4 (Tβ4) on neuronal apoptosis in rat middle cerebral artery occlusion ischemia/reperfusion (MCAO I/R) injury, and determine the mechanisms involved in this process. Forty‑eight adult male Sprague‑Dawley rats were randomly divided into three groups (n=16 per group): A sham control group, an ischemia/reperfusion group (I/R group), and a Tβ4 group. The focal cerebral I/R model was established by blocking the right MCA for 2 h, followed by reperfusion for 24 h. The Zea‑Longa method was used to assess neurological deficits. Cerebral infarct volume was assessed using 2,3,5‑triphenyltetrazolium chloride staining, and pathological changes were observed via hematoxylin and eosin staining. The terminal dexynucleotidyl transferase (TdT)‑mediated dUTP nick end labeling (TUNEL) assay was used to detect apoptosis. The expression of glucose‑regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), and caspase‑12 (CASP12) protein was assessed using immunohistochemistry and western blotting 24 h after reperfusion. Infarct volume and neuronal damage in the I/R and Tβ4 groups were significantly greater than those observed in the sham group. The Zea‑Longa score, neuronal apoptosis, and expression of GRP78, CHOP, and CASP12 in the I/R and Tβ4 groups were significantly higher than those reported in the sham group. However, the Longa score and neuronal apoptosis were lower in the Tβ4 group compared to the I/R group. The expression of GRP78 was significantly increased, whereas that of CHOP and CASP12 was significantly decreased in the Tβ4 group compared to the I/R group. The present data revealed that Tβ4 can inhibit neuronal apoptosis by upregulating GRP78 and downregulating CHOP and CASP12, thereby reducing cerebral I/R injury.

Topics: Animals; Apoptosis; Brain Ischemia; Disease Models, Animal; Immunohistochemistry; Male; Neurons; Rats; Reperfusion Injury; Thymosin

Random skin flaps can be used throughout the hands and fingers. Thymosin β4 can increase blood flow and reduce ischemia-reperfusion injury; the study was undertaken to investigate the effect of thymosin β4 on the survival of random skin flaps.. A total of 45 male Sprague-Dawley rats were used and subjected to a random-pattern skin flaps operation. Rats were randomly divided into three groups: a control group (group A: intraperitoneal injection of saline, 5 mg/kg/d) and two treatment groups (group B: intraperitoneal injection of thymosin β4, a single 5 mg/kg dose per day) and (group C: intraperitoneal injection of thymosin β4, 5 mg/kg dose twice per day). The flap surviving area was measured after 7 days, and tissue samples were stained with hematoxylin and eosin. Vascular endothelial growth factor (VEGF) expression was determined using immunohistochemical methods. Superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were examined with kits.. Thymosin β4 significantly reduced the necrotic area in the treatment groups after 7 days compared with the control group, and the rats receiving thymosin β4 5 mg/kg twice per day had the highest survival rate. VEGF expression and SOD activity markedly increased in the treatment groups compared with the control group, whereas MDA levels were lower in the treatment groups than in the control group.. Thymosin β4 may have a dose-dependent effect to promote the survival of random skin flaps.

Topics: Animals; Dose-Response Relationship, Drug; Immunohistochemistry; Injections, Intraperitoneal; Male; Microfilament Proteins; Microvessels; Rats, Sprague-Dawley; Regional Blood Flow; Reperfusion Injury; Superoxide Dismutase; Surgical Flaps; Thymosin; Vascular Endothelial Growth Factor A