OBJECTIVETo study the expression and significance of apoptosis-related protein p53, Bcl-2, and Bax during the development of oral squamous cell carcinoma (SCC).

METHODSThe expression was observed in 10 normal oral epithelia, 48 dysplasia epithelia and 42 SCC by immunohistochemical evaluation.

RESULTSIn normal mucosa, the positive rate of p53, Bcl-2 and Bax were 0%, 20% and 60%. In dysplasia epithelia, the positive rate of p53 is increased (P < 0.05), the positive rate of Bcl-2 and Bax remained no significant change (P > 0.05), but the positive intensity in severe dysplasia was higher than in mild group. In SCC, the positive rate of Bcl-2 increased significantly (compared with dysplasia, P < 0.05), while the expression of Bax was decreased with the increase of SCC histological grade. Further analysis showed the correlation was evident in p53 and Bax in dysplasia, and in p53 and Bcl-2 in SCC.

CONCLUSIONSIn dysplasia, p53 gene mutation results in accumulation of dysplasia cells. In SCC, the cooperation of p53, Bcl-2 and Bax results in the progression of SCC. Apoptosis genes could work either independently or cooperatively.

Apoptosis ; genetics ; Carcinoma, Squamous Cell ; chemistry ; Humans ; Immunohistochemistry ; Mouth Mucosa ; chemistry ; pathology ; Mouth Neoplasms ; chemistry ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Tumor Suppressor Protein p53 ; analysis ; bcl-2-Associated X Protein

OBJECTIVETo investigate the effect and mechanism of arsenic trioxide (As(2)O(3)) on the prevention of restenosis after vascular injury.

METHODSApoptosis induction of As(2)O(3) on cultured rabbit vascular smooth muscle cells (VSMCs) in vitro was observed. Thirty-two New Zealand white rabbits were randomly divided into 2- and 4-wk study groups, and their controls. 10% As(2)O(3) at 2.5 mg x Kg(-1) x d(-1) or 0.9% sodium chloride was intraperitoneally infused for 3 days before left common carotid arteries were denudated with a balloon. After denudation 2- and 4-wk animals were sacrificed for morphometry and immunohistochemical studies on carotid arteries, and for histopathology on liver and kidney.

RESULTSIt was shown via cellular morphology and DNA fragments in electrophoresis that promotion of As(2)O(3) on cultured vascular smooth muscle cell apoptosis was dependent upon its concentration and duration. Compared with the control animals, the mean vascular intimal proliferation areas were reduced in 2-wk study animals (P < 0.05) and no difference was shown in 4-wk (P > 0.05), while the mean vascular luminal areas were all enlarged in both study groups (all P < 0.05). The downregulated bcl-2 expression (all P < 0.05 in 2- and 4-wk) and the upregulated bax expression (P < 0.01 in 2-wk; P < 0.05 in 4-wk) were detected by immunohistochemistry, in comparison with control groups. Gene bcl-2 and bax protein expression were consistent with the suppression of intimal proliferation and the enlargement of luminal areas in corresponding sections.

CONCLUSIONAs(2)O(3) induces apoptosis of VSMCs and inhibits experimental restenosis effectively after artery injury, via downregulation of bcl-2 and upregulation of bax expression.

Animals ; Apoptosis ; Arsenicals ; pharmacology ; DNA ; analysis ; Female ; Flow Cytometry ; Male ; Muscle, Smooth, Vascular ; cytology ; drug effects ; Oxides ; pharmacology ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Rabbits ; Vascular Diseases ; prevention & control ; bcl-2-Associated X Protein

OBJECTIVETo investigate the effects of Matrine on apoptosis of fibroblasts and the expression of apoptotic modulation related protein in the hypertrophic scar.

METHODSHypertrophic scar was produced on the ear of 24 New Zealand white rabbits, which were employed as the model, and were randomly and equally divided into control (CC) and Matrine (M) groups (12 in each group). Matrine (50 g/L) was injected into the ear scar in M group and with normal saline in C group once every four days. At 2, 4, 6, 8 and 12 weeks after the injection, the apoptotic fibroblast count in the scar was determined by TUNEL method, and the expressions of apoptosis related modulation proteins p53, bcl-2, bax were detected by immunohistochemistry method.

RESULTSThe apoptotic fibroblast count was much larger in M group than that in C group at all test time points (P < 0.05). Furthermore, the bax expression was increased and that of p53 and bcl-2 was decreased significantly in M group. In adding, the scar became flat in M group.

CONCLUSIONMatrine might obviously enhance the fibroblast apoptosis in rabbit ear hypertrophic scar, and up-regulate the expression of apoptosis related modulation protein bax and down-regulate the expression of p53 and Bcl-2.

Alkaloids ; pharmacology ; Animals ; Apoptosis ; drug effects ; Cicatrix, Hypertrophic ; metabolism ; pathology ; Female ; Fibroblasts ; drug effects ; Immunohistochemistry ; Male ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Quinolizines ; Rabbits ; Tumor Suppressor Protein p53 ; analysis ; bcl-2-Associated X Protein

OBJECTIVETo investigate the therapeutic effect of Bcl-2 fusion protein on apoptosis in brain following traumatic brain injury.

METHODSBcl-2 gene was cloned by RT-PCR. Bcl-2 and EGFP genes were linked together and inserted into pAdeno-X vector. This recombinant vector was packaged into infectious adenovirus in HEK293 cells. Ninety Wistar rats were assigned randomly into experimental group (n=45) and control group (n=45). All rats were subjected to traumatic brain injury. Then recombinant adenovirus (for experimental group) or saline (for control group) was injected into the traumatic brain. The expression of Bcl-2 fusion protein was investigated by Western blotting, immunohistochemistry and fluorescence microscopy. Apoptosis in the injured brain was studied by TUNEL. Animals' behavior capacity was evaluated by tiltboard test.

RESULTSIn the experimental group, many fluorescent cells were found around the traumatic locus, which were also proven to be Bcl-2 positive by immunohistochemistry. On the contrary, few Bcl-2 positive cells and no fluorescent cell were detected in the control group. Bcl-2 expression of experimental group was much higher than that of control group, which was illustrated by Western blotting. The apoptosis index of experimental group was 0.027+/-0.005, and that of control group was 0.141+/-0.025 (P < 0.01). Two weeks after injury, animals of the experimental group behaved better than those of the control group.

CONCLUSIONSA recombinant adenovirus vector expressing Bcl-2 fusion protein has been constructed. Bcl-2 fusion protein can suppress apoptosis and promote cell survival. Moreover, the behavior recovery of the injured animal is promoted. Bcl-2 fusion protein provides a way to track the target cells in vivo.

Adenoviridae ; genetics ; Animals ; Apoptosis ; Base Sequence ; Brain Injuries ; therapy ; Cloning, Molecular ; Genes, bcl-2 ; Genetic Therapy ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Rats ; Rats, Wistar

OBJECTIVETo clarify if programmed cell death mechanisms induced by seizures take part in the necrotic process of neurons.

METHODSSeizure was induced by pilocarpine (P) in Sprague-Dawley adult rats which were allowed to recover for 24 or 72 hours before perfusion-fixation. Neuronal death was assessed by light microscopy with the hematoxylin-eosin (HE) staining and with in situ terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Bax and Bcl-2 protein expression were examined by histochemistry.

RESULTSTwenty-four and 72 hours after seizures, neuronal death in hippocampus CA1 region was morphologically necrotic. TUNEL-positive and morphologically necrotic cells increased in the hippocampal CA1 region at 72 hours after seizures, there was significant difference compared with controls (P < 0.001). Bax expression was also increased in the hippocampal CA1 region at 72 hours after seizures (P < 0.001), but Bcl-2 expression did not increase, while Bcl-2/Bax ratio decreased.

CONCLUSIONSeizures induced late-onset neuronal necrosis was accompanied by programmed cell death mechanisms.

Animals ; Apoptosis ; Hippocampus ; chemistry ; pathology ; In Situ Nick-End Labeling ; Male ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Rats ; Rats, Sprague-Dawley ; Seizures ; chemically induced ; physiopathology ; bcl-2-Associated X Protein

OBJECTIVETo investigate the role of apoptosis in radiation-induced mouse thymus lymphocyte damage and repair and provide the basis for understanding the molecular mechanism of radiation-induced lymphocyte damage and repair as well as the prevention and treatment of acute radiation sickness.

METHODSWe studied the dynamic changes of apoptosis of mouse thymus lymphocytes and the expression of bax and bcl-2 gene products after 2, 4, 6 and 8 Gy of whole body gamma-irradiation using in situ terminal labeling, DNA electrophoresis and immunohistochemical techniques.

RESULTSAt the early stage after irradiation, the percentage of apoptotic lymphocytes increased rapidly in accordance with the increasing of radiation doses, while the counts of the thymus and peripheral lymphocytes decreased sharply, showing an opposite change to lymphocyte apoptosis. After 6 Gy gamma-irradiation, typical morphological characteristics of thymus apoptotic lymphocytes in early, middle and late stages were found by transmission electron microscopy. The thymus lymphocytes displayed characteristic DNA ladders 4 hr and 8 hr after 2-6 Gy gamma-irradiation,using DNA gel electrophoresis techniques. Abnormal expression of bcl-2 and bax gene products were shown in irradiated lymphocytes.

CONCLUSIONSApoptosis plays an important role in the process of radiation-induced mouse thymus lymphocyte damage and repair. Bcl-2 and Bax proteins may regulate the process of lymphocyte apoptosis.

Animals ; Apoptosis ; radiation effects ; Dose-Response Relationship, Radiation ; Gamma Rays ; Lymphocytes ; physiology ; radiation effects ; Male ; Mice ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Thymus Gland ; pathology ; radiation effects ; Time Factors ; bcl-2-Associated X Protein

OBJECTIVETo investigate the effect of handportable mobiletelephone microwave radiation on rat central nervous system by setting up rat model.

METHODS80 healthy male SD rats (weighed about 200 g) were divided into 4 groups at random: control, radiation, decranium, decranium + radiation. TUNEL method was adopted used to detect the apoptosis of neurons after irradiation, then immunohistochemistry was used to detect Bcl-2, Bax expression in all brain tissue.

RESULTSTUNEL positive rate, Bax and Bcl-2 positive cell numbers could be found in decranium + radiation group [(26.45 +/- 9.27)%, (23.5 +/- 3.58), (11.1 +/- 2.55) respectively]. There were significant differences among control [(9.59 +/- 2.55)%, 14.2 +/- 2.46, 7.0 +/- 1.14 respectively], decranium group [(9.52 +/- 1.93)%, 15.5 +/- 1.77, 7.4 +/- 1.76], radiation group [(10.04 +/- 3.62)%, 15.9 +/- 2.02, 7.2 +/- 1.07] (P < 0.01). But the difference was not found in the ratio of Bax to Bcl-2.

CONCLUSIONMicrowave radiation did not affect the intact rat, but did promote the occurrence of neuron apoptosis in cranial defect rat. Bax, Bcl-2 gene participated in regulation of apoptosis. The intact cranium may be an important factor to protect the neurons against handportable mobiletelephone microwave radiation to some extent.

Animals ; Apoptosis ; radiation effects ; Brain ; pathology ; radiation effects ; In Situ Nick-End Labeling ; Male ; Microwaves ; adverse effects ; Neurons ; pathology ; radiation effects ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Rats ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein

Humans ; In Situ Hybridization, Fluorescence ; Membrane Proteins ; analysis ; NF-kappa B ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Tissue Array Analysis ; methods ; Tumor Cells, Cultured

OBJECTIVETo observe the expression of bcl-2 and bcl-xL in rat brain neuron after acute brain trauma.

METHODSThe rat model of mild and sever brain trauma were made by diffused brain injury. The expression of bcl-2 and bcl-xL in rat brain neuron was examined by immunohistochemical staining. Rat neuron apoptosis was detected by TUNEL method.

RESULTSThere were few bcl-2 (cortex: 4.40 +/- 1.67, hippocampal: 3.20 +/- 1.30) and lots of bcl-xL (cortex: 45.60 +/- 4.34, hippocampal: 50.20 +/- 3.50) expression in normal controls. After impact, the expression of bcl-2 in rat brain neuron increased, most distinctly on day 1(cortex: 30.0 +/- 4.3, hippocampal: 46.6 +/- 3.2), in mild group. A negative correlation was seen between bcl-2 expression and neuronal apoptosis (-1 < r < -0.847, P< 0.01, n = 10). No change was seen in bcl-xL expression.

CONCLUSIONSbcl-2 expression increased after acute brain trauma but bcl-xL did not change much. Both bcl-2 and bcl-xL are concerned with anti-apoptosis in neuron after acute brain trauma.

Acute Disease ; Animals ; Apoptosis ; Brain Injuries ; metabolism ; pathology ; Immunohistochemistry ; Male ; Neurons ; chemistry ; pathology ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Rats ; Rats, Wistar ; bcl-X Protein

OBJECTIVETo explore the molecular mechanism of brain protection against convulsive brain damage in premature brains by observing the changes of apoptotic-regulating genes of bcl-2 and c-Jun expression in the hippocampus in Wistar rats with different ages after status convulsion (SC).

METHODSSC was induced in infant Wistar rats (IRs) and adult Wistar rats (ARs) by intraperitoneal injection of lithium-pilocarpine. The rats were sacrificed at 3 hrs, 6 hrs, 12 hrs, 1 day, 3 days and 7 days after SC (n=8). Bcl-2 and c-Jun protein and mRNA levels were measured using immunocytochemistry, RT-PCR and in situ hybridization.

RESULTSc-Jun protein levels increased significantly at 3 hrs and reached the peak at 6 hrs after SC in both IRs and ARs compared to those in the normal control group (P<0.01). c-Jun protein levels started to decrease 12 hrs after SC in both IRs and ARs. The expression of c-Jun protein in IRs returned to the basal level 1 day after SC, while remained higher in ARs than in the normal control group by 7 days after SC. The expression of c-Jun protein in ARs was much higher than that in IRs from 6 hrs to 7 days after SC (P<0.05). c-Jun mRNA level was in parallel with the protein level as mentioned in IRs and ARs after SC. There were no changes observed in both bcl-2 protein and bcl-2 mRNA levels after SC in IRs and ARs.

CONCLUSIONSSC may induce an up-regulation of proapoptotic gene c-Jun in the hippocampus after SC, with a less strong extent and shorter duration in IRs compared to that in ARs. This might be one mechanism of brain protection against convulsive brain damage in IRs. The expression of bcl-2 remains unchanged after SC and is not affected by age in both IRs and ARs.

Animals ; Apoptosis ; Gene Expression Regulation ; Hippocampus ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; genetics ; Proto-Oncogene Proteins c-jun ; analysis ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Wistar ; Seizures ; metabolism