Biomedical subjects

M Rahmani

Publications and source records attributed to M Rahmani.

At least 19 recordsLinked to original sources

PubMed2006

Curcumin inhibits in vitro MCP-1 release from mouse pancreatic islets.

OBJECTIVES: Monocyte chemoattractant proteins (MCP-1) belongs to the CC family of chemokines secreted from islets of the pancreas, producing recruitment of inflammatory cells leading to an acute immune response with graft rejection in clinical transplantation. Expression and release of many inflammatory cytokines and chemokines, including MCP-1 is regulated by the nuclear factor (NF)-kappaB pathway. Curcumin is an NF-kappaB inhibitor with a variety of biological activities anti-inflammatory, antitumor, antioxidant, and antichemotactic effects. The aim of this study was to examine the effect of curcumin on in vitro MCP-1 release from pancreatic islets. METHODS: Mouse pancreatic islets in 18-hour cultures were treated with 0 or 10 or 20 micromol/L curcumin and with LPS for an additional 24 hours. MCP-1 levels in culture supernates of islets with versus without curcumin treatment were measured by an ELISA assay. RESULTS: We observed that curcumin at the concentration of 20 micromol/L significantly decreased MCP-1 release from mouse islets compared to the control group (P = .005). In addition at both of 10 micromol/L and 20 micromol/L curcumin concentrations there was a decreased level of MCP-1 released from LPS-treated versus control islets (P = .01).

Animals↗

PubMed2006

[Neuropsychological and magnetic resonance imaging findings in five patients after carbon monoxide poisoning].

INTRODUCTION: Carbon monoxide (CO) poisoning has been shown to result in cognitive impairments. These disorders have rarely been reported. The present study aimed to evaluate these disturbances in five patients with a neuroanatomical study. METHODS: There were two men and three women with an average of 25 years old. Patients were explored several months after acute CO poisoning. Neuropsychological testing was administered to assess memory, intellectual, executive, visual-spatial and constructional functions, language, praxis and gnosis. Cerebral magnetic resonance imaging (MRI) was performed in all patients using axial, sagittal and coronal slides with T1 and T2 weighted and flair images. None of the subjects had hyperbaric oxygen. They received 7, 5 mg bromocriptine per day. RESULTS: All patients presented cognitive disorders including marked impairment in long term memory with a severe defect in recall performance in comparison to recognition memory. Visual memory was more affected than the verbal one. There were also moderate disturbances in intellectual, executive, visual-spatial and constructional functions. One patient presented alexia agraphia, severe visual disturbances, constructional and dressing apraxia. Four patients had depression and one psychic akinesia. Cerebral MRI studies revealed that all patients had bilateral pallidal necrosis, bilateral hippocampal and moderate cortical atrophy. Fornix atrophy was found in 2 patients and corpus mammillary atrophy in 3 patients. Others lesions were also found: bilateral cerebellar in two cases and cortical in three cases. Treatment with bromocriptine was effective in three cases. There was no improvement in the patients treated 14 months and 5 years following CO poisoning. CONCLUSION: Neuropsychological impairments in CO poisoned subjects include memory, intellectual, executive, and visuospatial defects. In addition to pallidal necrosis, which is a typical feature of CO poisoning, hippocampal and cortical atrophy are often present. Bromocriptine can improve the cognitive disorders.

Adolescent↗

PubMed2006

Xanthones from Garcinia mangostana (Guttiferae).

Studies on the stem of Garcinia mangostana have led to the isolation of one new xanthone mangosharin (1) (2,6-dihydroxy-8-methoxy-5-(3-methylbut-2-enyl)-xanthone) and six other prenylated xanthones, alpha-mangostin (2), beta-mangostin (3), garcinone D (4), 1,6-dihydroxy-3,7-dimethoxy-2-(3-methylbut-2-enyl)-xanthone (5), mangostanol (6) and 5,9-dihydroxy-8- methoxy-2,2-dimethyl-7-(3-methylbut-2-enyl)-2H,6H-pyrano-[3,2-b]-xanthene-6-one (7). The structures of these compounds were determined by spectroscopic methods such as 1H NMR, 13C NMR, mass spectrometry (MS) and by comparison with previous studies. All the crude extracts when screened for their larvicidal activities indicated very good toxicity against the larvae of Aedes aegypti. This article reports the isolation and identification of the above compounds as well as bioassay data for the crude extracts. These bioassay data have not been reported before.

Aedes↗

PubMed2005

Reappraisal of the risk of iodine-induced hyperthyroidism: an epidemiological population survey.

The occurrence of iodine-induced hyperthyroidism (IIH) has been reported after iodine supplementation from clinics and hospitals, but not following an epidemiologic survey. We studied the prevalence of thyroid derangement in a population following iodine supplementation. One yr after more than 75% of the population had been consuming 40 ppm iodized salt; information regarding history of endemic goiter and iodized salt production, distribution, consumption and monitoring were collected in four cities of the Islamic Republic of Iran. A total of 6048 subjects were randomly selected. All subjects were assessed for size of goiter, and urinary iodine and serum T4, T3, TSH, anti-thyroglobulin and anti-thyroperoxide were measured. Before iodine supplementation, all four cities were areas of endemic goiter. The rate of household consumption of iodized salt was 50, 75 and 90% in 1994, 1995 and 1996, respectively. Ninety-one percent of the salt samples contained 15-55 ppm iodide. Total goiter rate was 57, 62 and 68%; median urinary iodine was 188, 197 and 190 microg/l in the age groups of 6-18, 19-40 and >40 yr, respectively. Prevalence of clinical and subclinical hyperthyroidism was 0.34 and 0.41 and those of clinical and subclinical hypothyroidism were 0.51 and 1.07%, respectively. Nine point eight and 18% in the 19-40 yr age group and 17.6 and 25.6% in >40 yr old subjects had positive anti-thyroperoxidase and anti-thyroglobulin, respectively. This systemic epidemiologic study in an iodine deficient population showed that, following a well-executed iodine supplementation program, the occurrence of IIH is rare.

Adolescent↗

PubMed2004

Cardiovascular risk factors in males with hypertriglycemic waist (Tehran Lipid and Glucose Study).

BACKGROUND: Many studies performed on nontraditional risk factors have proposed a metabolic triad including increased serum level of apolipoprotein B, hyperinsulinemia and high small, dense LDL-C as a risk factor of cardiovascular diseases. Hypertriglycemic waist (increased waist circumference as well as high fasting triglyceride level) can be used as a simple criterion to predict the metabolic triad. The aim of this study was to investigate the prevalence of hypertriglycemic waist and the frequency of cardiovascular risk factors in the affected population. MATERIALS AND METHODS: The study was performed on 4169, 18-70 y-old male subjects of the population of Tehran Lipid and Glucose Study (TLGS). The subjects fell into four groups with respect to serum level of fasting triglycerides (Tg) and waist circumference (WC). Subjects of group 1 had serum Tg > or =1.8 mmol/l as well as WC > or =95 cm, while those of group 2 had Tg > or =1.8 mmol/l and WC <95 cm. The triglycerides level was less than 1.8 mmol/l in groups 3 and 4, whereas WC was > or =95 cm and lower than 95 cm, respectively. Cardiovascular risk factors, anthropometric and laboratory variables were compared between the groups. RESULTS: In total, 784 subjects had high serum levels of Tg as well as increased WC. The mean age of subjects was significantly higher in groups 1 and 3 compared to others (37+/-15, 48+/-14, 41+13 and 46+/-13 y of age in groups 4, 3, 2 and 1, respectively, P<0.001). The prevalence of cardiovascular risk factors was significantly higher in group 1 as compared with others. Systolic and diastolic blood pressure, body mass index and WC were significantly higher in group 1 than in the others. Serum total cholesterol, Tg and LDL-C were significantly higher in group 1 compared to others, whereas HDL-C was significantly lower in this group. The prevalence of subjects who had at least four risk factors was 75 and 8% in groups 1 and 4, respectively. CONCLUSION: Hypertriglycemic waist can be used as a simple criterion to predict cardiovascular risk factors.

Adolescent↗

PubMed2004

Mucigerin, a new coumarin from Calophyllum mucigerum (Guttiferae).

Our recent studies on the stem bark of Calophyllum mucigerum (Guttiferae) have yielded a new coumarin mucigerin, a prenylated xanthone cudraxanthone C and the common steroidal triterpenes friedelin and stigmasterol. Structural elucidations of these compounds were achieved using 1H NMR, 13C NMR, DEPT, COSY, HETCOR and HMBC experiments while MS gave the molecular masses. Cytotoxic assays using CEM-SS cell line (T-lymphoblastic leukemia) on the crude extracts of the stem bark indicated some activity. The crude extracts were also found to be moderately toxic against the larvae of Aedes aegypti. This article reports the isolation and identification of mucigerin as well as bioassay data.

Aedes↗

PubMed2003

Serum paraoxonase 1 activity is decreased in thyroid dysfunction.

Changes in serum lipid and lipoprotein concentrations occur frequently in disorders of thyroid function. LDL-cholesterol (LDL-C) oxidation susceptibility is higher in these patients than in normal population. This study aims at assessing lipids, lipoproteins, apolipoproteins and serum paraoxonase 1 (PON1) activity in patients with thyroid dysfunction. Ninety-nine patients with thyroid dysfunction, (49 hypothyroid and 50 hyperthyroid) were compared with 2 separately age- and sex-matched control groups. A fasting blood sample was obtained and serum total cholesterol, triglycerides, apolipoproteins A-I and B, and PON1 activity were measured. In hyperthyroid patients, significantly lower PON1 activity (45 +/- 23 vs 67 +/- 37 IU/ml, p<0.001), triglycerides (112 +/- 53 vs 166 +/- 130 mg/dl, p<0.05), apolipoprotein A-I (137 +/- 26 vs 154 +/- 21 mg/dl, p<0.001) and apolipoprotein B (75 +/- 18 vs 86 +/- 25 mg/dl, p<0.05) were found. Hypothyroid patients had lower PON1 activity (46 +/- 21 vs 64 +/- 32 IU/ml, p<0.005) compared with controls, and higher total cholesterol (224 +/- 69 vs 185 +/- 41 mg/dl, p<0.001), LDL-C (133 +/- 59 vs 93 +/- 36 mg/dl, p<0.001), and apolipoprotein B (107 +/- 37 vs 84 +/- 23 mg/dl, p<0.001). The results show significant changes of lipid levels in thyroid dysfunction. In addition, a significant reduction in PON1 activity was observed in both hyper- and hypothyroid patients. Increased LDL-C oxidation in thyroid dysfunction observed in other studies, at least to some extent, can be attributed to reduced PON1 activity.

Adult↗

PubMed2003

Serum lipid levels in an Iranian adults population: Tehran Lipid and Glucose Study.

Data from 6246 participants aged 20-64 years (2339 males and 3907 females) in the cross-sectional phase of Tehran Lipid and Glucose Study (February 1999-May 2000) were used to determine distribution of serum lipid levels after 12-14 hour overnight fast. Mean total cholesterol (TC) concentration was 210 mg/dl. TC was significantly greater in females than males, 213 and 206 mg/dl, respectively (p < 0.0001). Thirty-one percent of population had TC values between 200 and 239 and 24% had values of 240 mg/dl or greater. Mean low-density lipoprotein cholesterol (LDL-C) was 129 and 135 mg/dl in males and females, respectively (p < 0.0001). Twenty-seven percent had LDL-C values between 130 and 159 and 23% had values 160 mg/dl or greater. The mean triglycerides (TGs) values were 190 and 162 mg/dl for males and females, respectively (p < 0.0001). The mean high-density lipoprotein cholesterol (HDL-C) was 39 in males and 45 mg/dl in females (p < 0.0001). The results showed higher levels of TC, LDL-C and TGs and slightly lower HDL-C in Tehranian adults than other studies in the industrialized countries.

Adult↗

PubMed2002

Distribution of blood pressure and prevalence of hypertension in Tehran adult population: Tehran Lipid and Glucose Study (TLGS), 1999-2000.

The purpose of this study was to estimate the current prevalence and distribution of hypertension in an adult Tehranian population. Data were collected for 3343 men and 5148 women aged 20-69 years in the Tehran Lipid and Glucose Study (TLGS), which is a cross-sectional phase of a large epidemiologic study, first established in 1999. The study used the mean of two separate blood pressure (BP) measurements in each individual. Twenty-two percent (23% of women vs 20% of men, P = 0.01) had hypertension according to 'JNC-VI' and 'WHO-ISH' criteria. The average systolic BP (SBP), diastolic BP (DBP) and pulse pressure of hypertensive participants were 31, 16, and 15 mm Hg higher than the corresponding value for normotensives, respectively. Thirty-six percent of participants with JNCVI-based hypertension were using antihypertensive medication (23% of men and 43% of women). Of these, 40% (45% of men and 39% of women) had normal BP. Hypertension awareness was 50% in these participants (57% in men vs 37% in women, P < 0.001). Data for 3179 men and 4646 women aged 20-69 years with no antihypertensive treatment were used for analysis of BP measures. Of these, 15% (16% of men and 14% of women, P = 0.006) had high and 85% (84% of men and 86% of women) normal or high-normal BP levels according to JNC-VI. Prevalence of optimal BP was 49% (47% of men and 51% of women). Mean SBP was 117.8 +/- 16.6 and 116.4 +/- 16.4 mm Hg in men and women, respectively (P < 0.001). The equivalent values were 77.4 +/- 10.7 and 77.3 +/- 9.9 mm Hg for DBP (P = 0.5) and 40.4 +/- 12 and 39.1 +/- 11.7 mm Hg for pulse pressure (P < 0.001). A relatively high prevalence of JNC-VI/WHO-ISH defined hypertension was found in the TLGS adult population with 50% undiagnosed and 60% uncontrolled hypertension. These findings emphasise further considerations for detection and better management of hypertension in the urban population of Tehran.

Adult↗

PubMed2002

Synergistic induction of apoptosis in human myeloid leukemia cells by phorbol 12-myristate 13-acetate and flavopiridol proceeds via activation of both the intrinsic and tumor necrosis factor-mediated extrinsic cell death pathways.

Previous studies have shown that coexposure to marginally toxic concentrations of phorbol 12-myristate 13-acetate (PMA; 10 nM) and the cyclin-dependent kinase inhibitor flavopiridol (FP; 100-200 nM) synergistically induces apoptosis in human myeloid leukemia cells U937 and HL-60 (i.e., >50% apoptotic at 24 h). Attempts have now been made to characterize the cell death pathway(s) involved in this phenomenon. In contrast to cytochrome c release and caspase-3 activation, which occur within 2.5 h of PMA/FP coexposure, caspase-8 activation and Bid cleavage appeared as later events. Such findings implicate the mitochondria-dependent pathway in the initial induction of apoptosis by PMA/FP. However, U937 cells ectopically expressing CrmA, dominant-negative caspase-8, or dominant-negative Fas-associated death domain that were highly resistant to tumor necrosis factor (TNF)/cycloheximide-induced lethality displayed significant, albeit incomplete, resistance to PMA/FP-induced apoptosis after 24 h. Furthermore, coadministration of TNF soluble receptor significantly attenuated PMA/FP-induced apoptosis in U937 (p < 0.02) and HL-60 (p < 0.03) cells at 24 h. PMA/FP coadministration also triggered substantial increases in TNFalpha mRNA and protein secretion compared with the effects of PMA administered alone. The protein kinase C (PKC) inhibitor bisindolylmaleimide (1 microM) completely blocked PMA/FP-induced TNFalpha secretion in U937 cells and attenuated apoptosis. Taken together, these results suggest that coadministration of PMA with FP in myeloid leukemia cells initially triggers mitochondrial damage, an event followed by the PKC-dependent induction and release of TNFalpha, supporting a model in which the synergistic induction of leukemic cell apoptosis by this drug combination proceeds via both mitochondrial- and TNF receptor-related apoptotic pathways.

Antineoplastic Agents↗

PubMed2002

Determinants of serum HDL-C level in a Tehran urban population: the Tehran Lipid and Glucose Study.

BACKGROUND AND AIM: Decreased serum high-density lipoprotein cholesterol (HDL-C) is one of the most common lipid disorders in patients with coronary artery disease (CAD). Existing evidence suggests that every 1 mg/dL decrease in serum HDL-C increases the risk of CAD by 2-3%. This study was performed in the year 2000 to study HDL-C determinants in a Tehran population. METHODS AND RESULTS: We studied 9514 subjects (3942 men and 5572 women) aged 20-69 years, who participated in the Tehran Lipid and Glucose Study (TLGS), completed a personal history questionnaire (especially concerning physical activity and cigarette smoking), and underwent a clinical examination including anthropometric and blood pressure measurements. Serum total cholesterol, triglyceride and HDL-C levels were measured, and OGTT was used to define diabetic patients according to WHO criteria. The women had a significantly higher mean HDL-C level than the mean (45 +/- 11 vs 38 +/- 9 mg/dL; p < 0.001); low HDL-C levels (< 35 mg/dL) were observed in 31% of the men and 13% of the women (p < 0.001). Obese subjects (BMI > or = 30 kg/m2) had a significantly lower HDL-C level than the normal subjects (42 +/- 11 vs 44 +/- 11 mg/dL: p < 0.001), and those with truncal obesity (WHR > or = 0.95 in men and > or = 0.8 in women) lower HDL-C levels than the normal subjects (37 +/- 9 vs 39 +/- 10 mg/dL in men and 44 +/- 11 vs 42 +/- 11 mg/dL in women; p < 0.001 for both). Smokers had a significantly lower HDL-C level than non-smokers (38 +/- 10 vs 43 +/- 11 mg/dL; p < 0.001) and a low HDL-C level was twice as common (36.4 vs 18.2%). Passive smokers also had lower HDL-C levels (42 +/- 11 vs 43 +/- 11 mg/dL; p < 0.001). Mean serum HDL-C was significantly lower in hypertriglyceridemic than those with normal triglycerides levels (men: 4 +/- 8 vs 40 +/- 9 mg/dL, p < 0.001; women: 40 +/- 10 vs 47 +/- 11 mg/dL, p < 0.01). Mean HDL-C levels were similar in subjects with different degrees of physical activity, as well as between diabetics and non-diabetics and hypertensive and normotensive subjects. Multiple stepwise regression analysis showed that the determinants of serum HDL-C levels were, in order of entering the model: hypertriglyceridemia (OR 3.4, p < 0.001), male sex (OR 3.1, p < 0.001), cigarette smoking (OR 1.7, p < 0.001), obesity (OR 1.4, p < 0.01), age (OR 0.9, p < 0.05), high WHR (OR 1.2, p < 0.05), and passive smoking (OR 1.1, p < 0.05). Physical activity, hypertension, and diabetes mellitus did not enter the predictive model. CONCLUSION: Apart from age and sex which are constitutional, and unmodifiable variables, the determinants of HDL-C level (hypertriglyceridemia, obesity, truncal obesity, cigarette smoking, and passive smoking) can be used in community CAD prevention programmes.

Adult↗

PubMed2001

Functional cooperation between JunD and NF-kappaB in rat hepatocytes.

AP-1 and NF-kappaB are rapidly activated during liver regeneration. Whether these parallel inductions have potential functional implications is not known. Isolated rat hepatocytes were stimulated with two mitogens, epidermal growth factor or hepatocyte growth factor and with tumor necrosis factor alpha, a cytokine involved in the liver regenerative response in vivo and a strong inducer of NF-kappaB. All three cytokines increased AP-1 and NF-kappaB binding to their cognate cis-element and induced a 2.5-fold activation of NF-kappaB-dependent transcription. Inactivation of AP-1 by TAM67, a dominant negative mutant of AP-1 drastically inhibited basal and cytokine-induced NF-kappaB transactivation. Overexpression of Jun D, but not of the other Jun or Fos proteins increased by threefold NF-kappaB transactivation. Functional cooperation between JunD and p65 was demonstrated in a simple Gal-hybrid system. Finally, a twofold decrease in NF-kappaB transactivation was found in hepatocytes isolated from JunD(-/-) mice compared with hepatocytes from JunD(+/+) mice. Altogether these data demonstrate a functional cooperation of p65 with JunD, a major constituent of AP-1 in normal hepatocytes.

Animals↗

PubMed2001

Serum lipid levels in an Iranian population of children and adolescents: Tehran lipid and glucose study.

Data from 3148 participants aged 3-19 years (1447 males and 1701 females) in the cross-sectional phase of Tehran lipid and glucose study (February 1999-May 2000) were used to determine serum lipid levels [total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)] after 12-14 hours overnight fast. The values were analyzed by sex and age. Mean serum TC concentration was 170 mg/dl. TC was significantly greater in females than males (173 vs. 167 mg/dl, p < 0.05). The 90th and 95th percentiles for serum TC were 211 and 227 mg/dl, respectively. There was a significant decrease in mean TC in males during puberty. Thirty-one percent of population had TC values between 170 and 199 mg/dl and 16% had values of 200 mg/dl or greater. The mean TGs values were 103 for males and 108 mg/dl for females [non-significant (NS)]. The prevalence of high-risk values of TGs increased with age in males, reaching a peak at 17-19 years. The mean HDL-C level was 45 mg/dl. Mean HDL-C was highest at 7-10 years of age and decreased thereafter. The mean LDL-C was 102 in males and 107 mg/dl in females (NS). Twenty-two percent had LDL-C values between 110 and 129 mg/dl and 17% had values 130 mg/dl or greater. The results showed higher levels of TC, LDL-C and TGs and lower HDL-C in Tehranian children and adolescents than other studies. To design comprehensive public health programs to reduce serum lipid levels among Iranian children and adolescents, underlying factors for the high prevalence of dyslipoproteinemia should be sought.

Adolescent↗

PubMed2001

Dietary factors and body mass index in a group of Iranian adolescents: Tehran lipid and glucose study--2.

OBJECTIVE: To study the prevalence of overweight and obesity in an adolescent population in Tehran and to determine possible association with energy and nutrient intake and distribution of energy over the day. METHOD: A cross-sectional study on 177 boys and 244 girls between 10-19 years old was performed. Overweight and obesity were defined by using recommended body mass index (BMI) cut-off values for adolescents. Total energy intake, percent of energy derived from protein, carbohydrate and fat and percent of energy supplied by each meal and snack were assessed by means of two 24-hour dietary recalls. RESULTS: Prevalence of overweight and obesity was 10.7 and 5.1 in boys and 18.4 and 2.8 in girls, respectively. The composition of diet was not different between overweight/obese and normal weight subjects. BMI was related with breakfast energy percentage in girls (r = -0.18, p < 0.01), with total energy intake in boys (r = 0.23, p < 0.01), and with lunch energy percentage in both sexes. In boys (r = 0.16, p < 0.05) and in girls (r = 0.22, p < 0.01). CONCLUSION: High prevalence of overweight and obesity among adolescents was seen. In boys some relationship between total energy intake, distribution of energy over the day and BMI was seen. In girls BMI was only related with distribution of energy over the day.

Adolescent↗

PubMed2000

Potentiation of Smad transactivation by Jun proteins during a combined treatment with epidermal growth factor and transforming growth factor-beta in rat hepatocytes. role of phosphatidylinositol 3-kinase-induced AP-1 activation.

Cross-talk between Smad and mitogen-activated protein kinase pathways has been described recently, and evidence for Smad cooperation with AP-1 is emerging. Here we report that epidermal growth factor (EGF) potentializes transforming growth factor beta (TGF-beta)-induced Smad3 transactivation in rat hepatocytes, an effect abrogated by TAM-67, a dominant negative mutant of AP-1. Antisense transfection experiments indicated that c-Jun and JunB were involved in the synergistic effect, and endogenous c-Jun physically associated with Smad3 during a combined EGF/TGF-beta treatment. We next investigated which signaling pathway transduced by EGF was responsible for the Jun-induced synergism. Whereas inhibition of JNK had no effect, inhibition of the phosphatidylinositol-3' kinase (PI3-kinase) pathway by LY294002 or by expression of a dominant negative mutant of PI3-kinase reduced EGF/TGF-beta-induced Smad3 transcriptional activity. Transfection of an activated Ras with a mutation enabling the activation of the PI3-kinase pathway alone mimicked the EGF/TGF-beta potentiation of Smad3 transactivation, and TAM-67 abolished this effect, suggesting that the PI3-kinase pathway stimulates Smad3 via AP-1 stimulation. The EGF/TGF-beta-induced activation of Smad3 correlated with PI3-kinase and p38-dependent but not JNK-dependent phosphorylation of c-Jun. Since potentiation of a Smad-binding element-driven gene was also induced by EGF/TGF-beta treatment, this novel mechanism of Jun/Smad cooperation might be crucial for diversifying TGF-beta responses.

Animals↗

PubMed2000

Fas- and interferon gamma-induced apoptosis in Chang conjunctival cells: further investigations.

PURPOSE: Previously interferon (IFN)gamma-induced apoptosis and expression of inflammation-related proteins in a human conjunctival cell line were demonstrated. The aim of this study was to further investigate the mechanisms of IFNgamma-, Fas-, and cycloheximide (CHX)-induced programmed cell death, with special attention to the role of transcriptional factors NF-kappaB and STAT1. METHODS: In a human conjunctival cell line (Chang conjunctival cells) apoptosis was induced with 500 ng/ml anti-Fas antibody (anti-Fas ab) alone (24 or 48 hours) or, as previously reported, with 300 U/ml of human recombinant IFNgamma alone (48 hours). To study the role of IFNgamma on Fas-induced apoptosis, cells were treated first with IFNgamma at 30 U/ml during 24 hours (nontoxic dose), and then anti-Fas ab was applied for 24 hours. Moreover, to study the influence of CHX on Fas- and IFNgamma-induced apoptosis, cells were treated for 24 hours with 300 U/ml IFNgamma together with a nontoxic concentration (1 microg/ml) of CHX, or with 500 ng/ml anti-Fas ab together with 1 microg/ml CHX (24 hours). After treatment, cell viability (neutral red assay), mitochondrial membrane potential (rhodamine 123 assay), chromatin condensation (Hoechst 33342 assay), and the index Hoechst/neutral red were studied by cold light microplate cytometry. The apoptotic process was sought for by contrast phase microscopy and DAPI staining and was confirmed by immunoblotting of PARP. Activation of caspase-3 (CPP32) and caspase-8 were investigated by Western blot analysis. NF-kappaB and STAT DNA-binding activities were studied by electrophoretic mobility shift assays (EMSA). RESULTS: After 24 and 48 hours of treatment with anti-Fas ab alone, 15% to 20% and 30%, respectively, of apoptotic cells were observed. When anti-Fas sera were applied after IFNgamma pretreatment or together with CHX, 50% to 80% of cells demonstrated morphologic characteristics of programmed cell death. Apoptosis was confirmed by a cleavage of PARP and CPP32, by caspase-8 activation, and by an index Hoechst/neutral red greater than one. All these modifications were preceded by a decrease in mitochondrial membrane potential. EMSA revealed that NF-kappaB was activated after IFNgamma and anti-Fas ab treatments and inhibited after CHX treatment. STAT1 was strongly activated after IFNgamma treatment and only in a minor degree after anti-Fas ab treatment. STAT1-binding activity persisted after CHX treatment. CONCLUSIONS: The relative resistance of Chang cells toward Fas-induced apoptosis could be related to the activation of NF-kappaB. IFNgamma-induced programmed cell death preferentially involves the activation of STAT1 that counterbalances NF-kappaB antiapoptotic effects. In fact, Fas-induced apoptosis was potentiated by IFNgamma or CHX treatments. These results suggest that NF-kappaB activation could maintain cell viability as well as participate in IFNgamma-induced inflammatory modifications, whereas STAT1 activation could provide, in this model, a proapoptotic signal.

Antibodies, Monoclonal↗

PubMed1999

Hepatocyte growth factor activates the AP-1 complex: a comparison between normal and transformed rat hepatocytes.

BACKGROUND/AIMS: Stimulation of activator protein-1 (AP-1), a Fos/Jun complex, is a key event in the cell response to growth factors. We have investigated whether hepatocyte growth factor (HGF) induces differential AP-1 responses in normal and transformed rat hepatocytes, the 7777 cells. METHODS: Primocultures of isolated hepatocytes or 7777 cells were stimulated with HGF. Gene expression was evaluated by ribonuclease protection assay and Western blot analysis. AP-1 DNA binding activity was measured by electrophoretic mobility shift assay. Identification of the proteins bound to the probes was made by supershift assays with specific antibodies. Cells were electroporated with plasmids containing an AP-1-dependent chloramphenicol acetyl transferase (CAT) gene, and CAT activity was measured 24 h after treatment with medium alone or HGF. RESULTS: In both cell types, HGF triggered the same program of jun family mRNA activation, but distinct Fos/Jun proteins accumulated in the nucleus. HGF increased DNA-binding activity to the phorbol 12-O-tetradecanoate-13-acetate responsive element (TRE) in both cell types, but distinct TRE-binding proteins were recruited in the AP-1 dimers. HGF also increased consistently binding to a cAMP responsive element (CRE) in hepatocytes only. Finally, HGF triggered TRE- and CRE-dependent gene activations in hepatocytes but TRE-dependent gene activation alone in 7777 cells. CONCLUSIONS: HGF-induced AP-1 activation leads to the formation of distinct dimers with different functional capacities in normal and transformed hepatocytes. These data suggest the importance of qualitative abnormalities of the AP-1 complex for the establishment or maintainance of a transformed phenotype.

Animals↗

PubMed1998

Reality and danger in psychoanalytic treatment.

In recent papers there has been considerable interest in the disclosure of the analyst's erotic countertransference. In our view this discussion touches a more fundamental issue: must something "real" take place between analyst and patient in order for real change to occur? And if what takes place is "real," will it not be dangerous and potentially destructive? Tracing the history of psychoanalytic understandings of what is "real" in the patient's life and what is "real" in the transference, we explore these questions in a clinical vignette and discuss the implications of this issue for our understanding of the process of psychoanalytic treatment.

Countertransference↗