Nutritional status efficacy of early nutritional support in gastrointestinal care: A systematic review and meta-analysis

BACKGROUND

Gastrointestinal surgery is a complicated process used to treat many gastrointestinal diseases, and it is associated with a large trauma: Most patients often have different degrees of malnutrition and immune dysfunction before surgery and are prone to various infectious complications during postoperative recovery, thus affecting the efficacy of surgical treatment. Therefore, early postoperative nutritional support can provide essential nutritional supply, restore the intestinal barrier and reduce complication occurrence. However, different studies have shown different conclusions.

AIM

To assess whether early postoperative nutritional support can improve the nutritional status of patients based on literature search and meta-analysis.

METHODS

Articles comparing the effect of early nutritional support and delayed nutritional support were retrieved from PubMed, EMBASE, Springer Link, Ovid, China National Knowledge Infrastructure, China Biology Medicine databases. Notably, only randomized controlled trial articles were retrieved from the databases (from establishment date to October 2022). The risk of bias of the included articles was determined using Cochrane Risk of Bias V2.0. The outcome indicators, such as albumin, prealbumin, and total protein, after statistical intervention were combined.

RESULTS

Fourteen literatures with 2145 adult patients undergoing gastrointestinal surgery (1138 patients (53.1%) receiving early postoperative nutritional support and 1007 patients (46.9%) receiving traditional nutritional support or delayed nutritional support) were included in this study. Seven of the 14 studies assessed early enteral nutrition while the other seven studies assessed early oral feeding. Furthermore, six literatures had "some risk of bias," and eight literatures had "low risk". The overall quality of the included studies was good. Meta-analysis showed that patients receiving early nutritional support had slightly higher serum albumin levels, than patients receiving delayed nutritional support [MD (mean difference) = 3.51, 95%CI: -0.05 to 7.07, Z = 1.93, P = 0.05]. Also, patients receiving early nutritional support had shorter hospital stay (MD = -2.29, 95%CI: -2.89 to -1.69), Z = -7.46, P < 0.0001) shorter first defecation time (MD = -1.00, 95%CI: -1.37 to -0.64), Z = -5.42, P < 0.0001), and fewer complications (Odd ratio = 0.61, 95%CI: 0.50 to 0.76, Z = -4.52, P < 0.0001) than patients receiving delayed nutritional support.

CONCLUSION

Early enteral nutritional support can slightly shorten the defecation time and overall hospital stay, reduce complication incidence, and accelerate the rehabilitation process of patients undergoing gastrointestinal surgery.

Neuroprotective effects of NEP1-40 and fasudil on Nogo-A expression in neonatal rats with hypoxic-ischemic brain damage

The hypoxic-ischemic encephalopathy caused by peripartum asphyxia is a serious disease in newborn infants, and effective therapies need to be developed to reduce injury-related disorders. We evaluated the effects of NEP1-40 and fasudil on Nogo-A expression in neonatal hypoxic-ischemic brain damage (HIBD) rats. Seven-day-old Wistar rats were randomly divided into control, HIBD, NEP1-40, and fasudil groups. NEP1-40 and fasudil groups were injected intraperitoneally with these compounds. Rat brains at 6, 24, 72 h, and 7 days after HIBD were collected to determine histopathological damage and the expression levels of Nogo-A. Histopathological damage was reduced in NEP1-40 and fasudil groups compared with the untreated HIBD group. The expression of Nogo-A in the HIBD group was significantly higher than that in control, NEP1-40 and fasudil groups at the same times. Compared with the fasudil group, the expression levels of Nogo-A were significantly reduced in the NEP1-40 group. We conclude that NPE1-40 and fasudil have potential for neuroprotective effects in the neonatal rat HIBD model, mediated by inhibiting Nogo-A/ Rho pathways.

Genetic evolution of epidermal growth factor receptor in adenocarcinoma with a bronchioloalveolar carcinoma component

BACKGROUND

Epidermal growth factor receptor (EGFR) mutations may accumulate during the multistage progression of bronchioloalveolar carcinoma (BAC), leading to heterogeneity within the tumor. This study sought to determine whether metachronous adenocarcinomas with a BAC component emerging in the lung field arise from a single or multiple clones in the same individual.

MATERIALS AND METHODS

Samples of adenocarcinomas exhibiting various degrees of BAC were obtained by thoracotomy. Sequential specimens were obtained upon detection of metachronous lesions in the lung field. Genomic DNA was extracted from specimens, and the presence of activating mutations in EGFR was determined via direct sequencing. Our pathologic findings, sequential image information, and genetic data were compared to track evidence of cancer evolution.

RESULTS

Based on EGFR gene analyses of tumor specimens from 431 patients, 17 cases of sequential BAC-related adenocarcinomas, obtained by thoracotomy, were noteworthy. Upon alteration of the BAC/adenocarcinoma components, the EGFR tyrosine kinase inhibitor-untreated series, which had at least one episode of an EGFR-activating mutation, represented 3 potential hypotheses: no significant EGFR evolution for a single clone, genetic alterations from mutant to wild-type EGFR for multifocal lesions, or a switch from wild-type to mutant EGFR, leading to indeterminable cancer progression.

CONCLUSION

Genetic analysis, in conjunction with pathologic and radiologic diagnoses, can be used to explore the origin of multifocal BAC. The single-clone model indicates subsequent disease progression, whereas genetic alterations from mutations to wild-type EGFR are suggestive of second primary carcinoma. In cases when additional lesions emerge after the radical resection of BAC-related lung cancer, sequential tumor samples should be obtained for further evaluation.

Overexpression of clusterin correlates with tumor progression, metastasis in gastric cancer: a study on tissue microarrays

Clusterin (CLU) is expressed in a wide variety of human tissues and fluids. Overexpression of cytoplasmic clusterin (sCLU) has been implicated in cancer development and progression. The aim of the present study is to evaluate the association of sCLU overexpression with clinicopathological features of human gastric carcinomas (GC).We constructed a gastric cancer tissue microarray containing 173 primary gastric carcinomas and 70 paired non-neoplastic mucosa specimens. The expression of sCLU was studied by immunohistochemistry. The correlations between sCLU expression and clinicopathological features, p53 abnormality, as well as Ki67 activation were analyzed. Overexpressions of sCLU was detected in 28.5% (n=165) of primary GCs by immunohistochemical staining, but not in non-neoplastic mucosa. Clinical association study found that overexpression of sCLU was significantly correlated with lymph-node metastasis (p < 0.001), tumor invasion (p < 0.001) and TNM stage (p < 0.001). In Kaplan-Meier survival analysis, overexpression of sCLU was significantly correlated with unfavorable survival in advanced GCs (p < 0.03). Furthermore, the association of sCLU with abnormal expression of p53 was ascertained. These results suggested that overexpression of sCLU was involved in the progression of GC and it's oncogenic function might be associated with p53 abnormality. Overexpression of sCLU seems to be related with patient's shorter survival in late stage GC.

In vitro sequence-dependent synergism between paclitaxel and gefitinib in human lung cancer cell lines

PURPOSE

In clinical trials, the epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) administered concomitantly with first-line cytotoxicity chemotherapy failed to confer a survival benefit to patients with non-small-cell lung cancer (NSCLC). The aim of this study was to test whether paclitaxel followed by gefitinib is superior to other treatment schedules of NSCLC cell lines and to clarify the underlying mechanisms.

METHODS

Human lung cancer cell lines with wild-type and mutant-type EGFR genes were used as in vitro models to define the differential effects of various schedules of paclitaxel with gefitinib treatment on cell growth, signaling pathway, and cell cycle distribution.

RESULTS

Sequence-dependent antiproliferative effects differed between EGFR-TKI-resistant and EGFR-TKI-sensitive lung cancer cell lines. Exposure to paclitaxel resulted in an increased pEGFR level. This increase in phosphorylation was inhibited by subsequent exposure to gefitinib, whereas during the reverse sequence, the inhibition effect was reduced. After paclitaxel exposure, a higher level of pEGFR was observed in mitotic than in interphase cells. The sequence of paclitaxel followed by gefitinib resulted in greater anti-VEGF activity than did the reverse sequence. We confirmed that gefitinib arrested cells in G1, and paclitaxel arrested them in S phase. The sequence of paclitaxel followed by gefitinib arrested cells in G1, whereas the reverse sequence arrested cells in S and G2 phases.

CONCLUSIONS

These findings suggest that the sequence of paclitaxel followed by gefitinib may be superior to other sequences in treating NSCLC cell lines. Our results also provide molecular evidence to support clinical treatment strategies for patients with lung cancer.

RRM1 single nucleotide polymorphism -37C-->A correlates with progression-free survival in NSCLC patients after gemcitabine-based chemotherapy

Background

The ribonucleotide reductase M1 (RRM1) gene encodes the regulatory subunit of ribonucleotide reductase, the molecular target of gemcitabine. The overexpression of RRM1 mRNA in tumor tissues is reported to be associated with gemcitabine resistance. Thus, single nucleotide polymorphisms (SNPs) of the RRM1 gene are potential biomarkers of the response to gemcitabine chemotherapy. We investigated whether RRM1 expression in peripheral blood mononuclear cells (PBMCs) or SNPs were associated with clinical outcome after gemcitabine-based chemotherapy in advanced non-small cell lung cancer (NSCLC) patients.

Methods

PBMC samples were obtained from 62 stage IIIB and IV patients treated with gemcitabine-based chemotherapy. RRM1 mRNA expression levels were assessed by real-time PCR. Three RRM1 SNPs, -37C→A, 2455A→G and 2464G→A, were assessed by direct sequencing.

Results

RRM1 expression was detectable in 57 PBMC samples, and SNPs were sequenced in 56 samples. The overall response rate to gemcitabine was 18%; there was no significant association between RRM1 mRNA expression and response rate (P = 0.560). The median progression-free survival (PFS) was 23.3 weeks in the lower expression group and 26.9 weeks in the higher expression group (P = 0.659). For the -37C→A polymorphism, the median PFS was 30.7 weeks in the C(-)37A group, 24.7 weeks in the A(-)37A group, and 23.3 weeks in the C(-)37C group (P = 0.043). No significant difference in PFS was observed for the SNP 2455A→G or 2464G→A.

Conclusions

The RRM1 polymorphism -37C→A correlated with PFS in NSCLC patients treated with gemcitabine-based chemotherapy. No significant correlation was found between PBMC RRM1 mRNA expression and the efficacy of gemcitabine.

An autologous therapeutic dendritic cell vaccine transfected with total lung carcinoma RNA stimulates cytotoxic T lymphocyte responses against non-small cell lung cancer

OBJECTIVE

The development of immunotherapy for malignancy is greatly limited by the characteristic weak antigenicity of tumors. The primary goal of this study was to circumvent the isolation and purification of tumor-specific antigen determinants by producing a vaccine using lung tumor RNA-loaded dendritic cells (DCs), and to test the response against lung cancer.

METHODS

Total RNA was isolated from 18 lung carcinomas with positive carcinoembryonic antigen (CEA) and mucin-1 (MUC1) staining, as identified by immunohistochemistry. DCs and T-cells from peripheral blood mononuclear cells were generated in vitro, and then DCs in different stages were transfected with RNA using several different methods. The expression of CEA and MUC1 in RNA-transfected DCs was measured using flow cytometry. T-cells stimulated by DCs were harvested as effectors, and primary tumor cells cultured in vitro were used as targets. Cytotoxicity was determined by lactic dehydrogenase detection assay.

RESULTS

Immature RNA-transfected DCs significantly increased the expression of CEA and MUC1, compared to mature transfected DCs. RNA transfection via electroporation resulted in significantly greater CEA and MUC1 expression than did transfection via lipofection or passive pulsing. Lymphocytes stimulated by DCs transfected with lung tumor RNA initiated a cytotoxic T lymphocyte (CTL) tumor-specific response.

CONCLUSION

Immature DCs transfected with total lung carcinoma RNA by electroporation in vitro effectively stimulate antigen-specific CTL responses against tumor cells.

[Correlation of DNA-dependent protein kinase catalytic subunit expression to radiosensitivity of non-small cell lung cancer cell lines]

BACKGROUND AND OBJECTIVE

DNA-dependent protein kinase catalytic subunit (DNA-PKcs) plays an important role in repairing irradiation-induced DNA double-strand break (DSB), and affects the radiosensitivity of tissue cells. This study was to detect the expression of DNA-PKcs in different non-small cell lung cancer (NSCLC) cell lines and evaluate its correlation to radiosensitivity.

METHODS

The content and activity of DNA-PKcs in five NSCLC cell lines A549, H1299, L78, PGCL3 and H460 were measured by Western blot and the DNA-PK activity assay. Cell survival was analyzed using clonogenic formation assay.

RESULTS

The radiosensitivities of five NSCLC cell lines were different. The values of survival fraction at 2 Gy (SF2) were 0.74 in A549 cells, 0.25 in H1299 cells, 0.21 in H460 cells, 0.48 in PGCL3 cells, and 0.58 in L78 cells. The protein levels of DNA-PKcs were 3.26+/-0.98 in A549 cells, 0.51+/-0.07 in L78 cells, 0.51+/-0.11 in H1299 cells, 0.86+/-0.23 in H460 cells, and 2.60+/-0.76 in PGCL3 cells. The activity values of DNA-PKcs were 8.30+/-1.03 in A549 cells, 2.45+/-0.52 in H1299 cells, 0.11+/-0.02 in H460 cells, 4.13+/-0.87 in PGCL3 cells, and 0.42+/-0.07 in L78 cells. In adenocarcinoma and large cell carcinoma cell lines, SF2 were correlated to DNA-PKcs content (P<0.05, r=0.95) and activity (P=0.03, r=0.98).

CONCLUSION

DNA-PKcs is an important factor to predict the radiosensitivity in adenocarcinoma and large cell lung cancer cell lines.

Clinicopathologic and molecular features of epidermal growth factor receptor T790M mutation and c-MET amplification in tyrosine kinase inhibitor-resistant Chinese non-small cell lung cancer

To investigate the clinicopathologic and molecular features of the T790M mutation and c-MET amplification in a cohort of Chinese non-small cell lung cancer (NSCLC) patients resistant to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). EGFR TKI-resistant NSCLC patients (n = 29) and corresponding tumor specimens, and 53 samples of postoperative TKI-naïve NSCLC patients were collected. EGFR exon 19, 20, and 21 mutations were analyzed. And c-MET gene copy number was determined. The EGFR T790M mutation in exon 20 was not detected in the population of 53 TKI-naïve patients, but found in 48.3% (14/29) of the enrolled TKI-resistant patients. c-MET was amplified in 3.8% (2/53) of the TKI-naïve NSCLC patients and highly amplified in 17.2% (5/29) of the cohort. Most of T790M mutations were frequently associated with non-smoker, adenocarcinoma and EGFR activating mutations. Three male patients with T790M mutation occurred with wild-type EGFR, and were resistant to the treatments following TKI resistance. Features of c-MET amplification in TKI-naïve patients were indistinguishable from TKI-resistant patients. In the group of wild-type EGFR, patients with T790M mutation had median progression free survival (PFS) and overall survival (OS) as 9.6 months and 12.6 months, respectively; whereas the median PFS and OS of c-MET amplified patients was 4.1 months and 8.0 months, respectively. These results suggest that EGFR T790M mutation and c-MET amplification can occur in TKI-resistant NSCLC with wild-type EGFR, and these genetic defects might be related to different survival outcome. c-MET amplification in TKI-naïve or -resistant patients might share similarities in clinicopathologic features.

Cloning of recombinant plasmid affecting HER-2 in gene translation by RNA interference

AIM: To clone the recombinant plasmid affecting HER-2 gene translation by RNA interference, and to analyze the nucleic acid sequence of the recombinant plasmid for tumor gene therapy.

METHODS: Two DNA sequences containing a small hairpin structure were designed and synthesized. The complement form was obtained by annealing and cloning into vector pGPU6/GFP/Neo, and the recombinant plasmid was transformed into strain DH5α. The plasmid identified by restriction enzyme analysis was used for sequencing. Human colon cancer HT29 cells were transfected with plasmid vector, and then fluorescence photographs were taken and selected according to G418.

RESULTS: The recombinant plasmid was cloned, and the sequence was obtained.

CONCLUSION: Successful cloning of the recombinant plasmid may help to discover new gene therapies for tumors.

The epidermal growth factor receptor intron1 (CA) n microsatellite polymorphism is a potential predictor of treatment outcome in patients with advanced lung cancer treated with Gefitinib

The goal of our study was to assess the association between R497K and intron1 (CA) n repeat genetic polymorphisms of the EGF (epidermal growth factor) receptor and the clinical outcome of patients with advanced non-small cell lung cancer treated with EGF receptor tyrosine kinase inhibitor. We determined the genotypes for R497K and intron1 (CA) n repeat genetic polymorphisms of 70 Chinese patients with advanced non-small cell lung cancer. Genetic polymorphisms were correlated with the clinical outcome of treatment with EGF receptor tyrosine kinase inhibitor. In a subgroup of patients whose tumor tissues were available for mutation analysis and IHC (immunohistochemistry) assay, the associations between the EGF receptor mutations, the EGF receptor protein expression levels and EGF receptor polymorphisms were analyzed. The results indicated that patients with a lower number of EGF receptor CA repeats (any allele < or =16 CA) were more likely to have higher EGF receptor protein expression levels, better response, and longer survival time than were patients with a higher number of CA repeats (both alleles >16 CA) after therapy targeted at the EGF receptor (P=0.021; P=0.014; P=0.0392, respectively). In contrast, the R497K polymorphism had no relationship with EGF receptor protein expression levels or the clinical outcome of the patients treated with EGF receptor tyrosine kinase inhibitor (P=0.49; P=0.452, respectively), and there were no associations between the two polymorphisms and somatic mutations (P=0.916; P=0.562, respectively). Overall, our data suggest that the intron1 (CA) n polymorphism of the EGF receptor gene may be associated with the sensitivity to and the prognosis of non-small cell lung cancer after EGF receptor targeted inhibitor treatment.

KDR expression is associated with the stage and cigarette smoking of the patients with lung cancer

PURPOSE

Kinase insert domain-containing receptor (KDR) is one of the molecular targets used in cancer therapy. We studied the KDR expression characteristics and the relationship with the clinical parameters of the patients with lung cancer, to give the basic evidence and clue for tailoring therapy.

METHODS

Reverse transcriptase and real-time PCR were used to evaluate the KDR mRNA expression levels in 222 tissue samples (106 tumor tissues, 106 matched normal tissues obtained from the same patients with lung cancer, and 10 normal lung specimens from individuals without lung cancer). The KDR mRNA expression level and clinical parameters were analyzed by paired-sample t test, ANOVA and linear regression, respectively. The Kaplan-Meier method and the log-rank test were used for survival analysis. Expression of KDR protein was also examined immunohistochemically in 15 tumor samples and 15 matched normal lung specimens.

RESULTS

The KDR mRNA expression levels were significantly higher in normal tissues (mean 4.50 +/- 0.51) than that in the carcinoma tissues (mean 4.12 +/- 0.50, P < 0.0005). KDR expression in tumor tissues is associated with the histological status, tumor stage, cigarette smoking, and N stage of the patients with lung cancer (P < 0.05) analyzed by using ANOVA methods. Multivariate analysis showed that tumor stages and cigarette smoking status were the two most important independent predictors for the KDR expression levels in tumor tissues (R = 0.415, R (2) = 0.172, F = 10.694, P < 0.0005). Tumors with KDR mRNA expression levels above the mean had a shorter survival (466 +/- 313 days) than did patients with KDR expression levels below the mean (671 +/- 264 days), whereas Kaplan-Meier analysis and log-rank test showed no significant difference in the overall survival between the patients (P = 0.2055). All the 15 normal lung tissues detected showed scale 2 KDR immunostaining. The intensity of immunostaining for KDR in tumor specimens varied from negative (scale 0) to strongest (scale 3) staining.

CONCLUSIONS

Locally advanced and non-cigarette smoking patients with lung cancer may be the two valuable surrogate markers for KDR mRNA higher levels. Non-squamous lung cancer, N 2 stage may be the secondary markers for that. The KDR expression level in normal lung tissue is stable, but varied in tumor tissues. Targeting KDR therapy in lung cancer might considerate these clinical and KDR expression information. Further confirmation study must be needed.

[Correlation of NY-ESO-1 gene and protein expression to metastasis and clinicopathologic features of hepatocellular carcinoma]

BACKGROUND & OBJECTIVE

NY-ESO-1 belongs to cancer-testis antigen family. It can inspire both cellular and humoral immune responses in tumor patients, and is regarded as the strongest tumor antigen. This study was to investigate the expression of NY-ESO-1 gene and its correlation with clinicopathologic features of hepatocellular carcinoma (HCC).

METHODS

NY-ESO-1 mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR) in 62 specimens of HCC and adjacent liver tissue. NY-ESO-1 protein expression and its distribution were detected by immunohistochemistry (IHC) in a tissue microarray contained 132 eligible cases of HCC.

RESULTS

Positive rate of NY-ESO-1 mRNA was 27.4% in HCC; it was higher in HCC with tumor embolus of portal vein than in HCC without tumor embolism (40.0% vs. 18.9%). Positive rate of NY-ESO-1 protein was 18.9% in HCC tissue microarray; it was significantly higher in HCC with metastasis than in HCC without metastasis (29.6% vs. 11.5%, P < 0.05). NY-ESO-1 protein mainly located in cytoplasm of HCC cells. Positive rates of NY-ESO-1 mRNA and protein were 28.3% and 19.1% respectively in HBsAg positive HCC, and were 29.5% and 20.7% respectively in HCC with alpha fetoprotein (AFP) of > 20 ng/ml. Both NY-ESO-1 mRNA and protein were not detected in adjacent normal liver tissue.

CONCLUSIONS

NY-ESO-1 gene specifically expresses in HCC, and may correlates with progress and metastasis of HCC. It may be a candidate target for antigen-specific immunotherapy for HCC with metastatic lesion. NY-ESO-1 expression has no correlation with HBsAg/AFP status of HCC.

[Expressions of inducible nitric oxide synthase and vascular endothelial growth factor and their relationship with microvessel density in hepatocellular carcinoma]

BACKGROUND & OBJECTIVE

Inducible nitric oxide synthase (iNOS), and vascular endothelial growth factor (VEGF) are recognized as key factors required for angiogenesis of tumors. They can influence pathologic development and prognosis of tumors. This study was to investigate the correlation of expressions of iNOS and VEGF to angiogenesis of hepatocellular carcinoma (HCC).

METHODS

Tissue microarray of 147 specimens of HCC was prepared, VEGF and microvessel density (MVD) were detected using immunohistochemistry, iNOS mRNA was detected by in situ hybridization.

RESULTS

Positive rates of iNOS, and VEGF in HCC tissues were higher than those in adjacent noncancerous tissues (86.39% vs. 33.33%, 78.91% vs. 40.82%). Expression levels of iNOS, and VEGF in HCC tissues were significantly higher than those in adjacent noncancerous tissues (P<0.01). MVD in HCC tissues was significantly higher than that in adjacent noncancerous tissues (56.5+/-12.8 vs. 8.4+/-3.6, P<0.01). Expression of iNOS was related with tumor size, and surface antigen of hepatitis B (HBsAg) (P<0.05), but didn't relate with metastasis, and differentiation of the cancer (P>0.05). Expression of VEGF, and MVD were correlated to tumor size, and metastasis (P<0.05), not to HbsAg, and tumor differentiation (P>0.05). In cancer tissues, MVD was positively correlated with expressions of VEGF and iNOS (P<0.01), expression of VEGF was positively correlated with that of iNOS (P<0.01).

CONCLUSION

iNOS and VEGF may play important roles in angiogenesis of HCC. Expression levels of iNOS and VEGF, and MVD in HCC tissues were higher than those in adjacent noncancerous tissues.

[Study on immunoreaction induced by DCs loaded with hepatocarcinoma antigen peptide in-vitro]

AIM

To investigate the potency and antitumor effect of specific cytotoxic T lymphocytes induced by hepatocarcinoma antigen peptide EPVTKAEML-loaded dendritic cells (DCs).

METHODS

The healthy donors of HLA-B7 genotype were selected by PCR-SSP. Isolated and cultured DCs from HLA-B7 donors' spleen tissues were loaded with the peptide EPVTKAEML from hepatocarcinoma cell line HHCC. The specific CTL reaction and inhibitory effect of anti-HLA-I molecule mAb on CTL cytotoxicity were detected in-vitro by (51)Cr-release assay.

RESULTS

4 donors with HLA-B7 genotype were found. Their spleen T lymphocytes could be induced to proliferate and differentiate into specific CTLs by DCs loaded with the peptide. Antibody-blocking test demonstrated that the cytotoxity of CTLs was strictly limited by MHC-I molecule.

CONCLUSION

EPVTKAEML-loaded DCs can induce efficient and specific antitumor immune reaction in-vitro.

[Cloning of human testicular carcinoma antigen MAGE-E1 gene and its expression in E.coli]

AIM

To clone and express the testicular carcinoma antigen MAGE-E1 gene in E.coli.

METHODS

The cDNA encoding human MAGE-E1 gene was amplified by RT-PCR from human glioma cell line BT-325, then the MAGE-E1 gene was inserted into plasmid pGEM-T easy. After sequencing, the MAGE-E1 was cloned into the prokaryotic expression vector pGEX-4T-2 to construct the recombinant expression vector pGEX-4T-2-MAGE-E1 which was used to transform E.coli.

RESULTS

The expressed product reached the highest level at 5 h after IPTG induction. SDS-PAGE and scanning analysis of gel density indicated that the expressed protein was about M(r) 41 000 and account for 35% of the total bacterial protein.

CONCLUSION

The high efficient expression of the MAGE-E1 gene fragment lays the foundation for further preparing antibody against MAGE-E1 protein and the tumor vaccine for glioma immunotherapy.

Adrenergic and serotoninergic receptors mediate the immunological activation of corticosterone secretion in male rats

In order to elucidate the mechanism of action of immune agents on corticosterone secretion, the present study evaluated the possible involvement of some neuronal pathways (serotoninergic, noradrenergic/adrenergic) in the lipopolysaccharide (LPS)-induced corticosterone release in male rats. Serotoninergic antagonists, mianserin (5-HT2C receptor blocker) or pindolol (5HT1A receptor blocker) or noradrenergic/adrenergic antagonists, prazosin (alpha 1-adrenoceptor blocker) or propranolol (beta-adrenoceptor blocker), were intraperitoneally (i.p.) injected before (5 min) the administration of LPS. In each experiment a group of rats i.p. injected with vehicle served as controls. Animals were sacrificed by decapitation 90 min after administration of LPS and trunk blood was collected for corticosterone radioimmunoassay. Results showed that pretreatment with mianserin, but not with pindolol, significantly reduced plasma corticosterone levels following administration of LPS (p < 0.05); prazosin attenuated the plasma corticosterone response to LPS (p < 0.05), while propranolol did not induce significant change. The present study indicated that serotoninergic and noradrenergic/adrenergic pathways are involved in the immunoneuroendocrine modulation of hypothalamus-pituitary-adrenal function in rats. In particular, it is probably mediated by the activation of 5-HT2C receptors and of alpha 1-adrenoceptors, while type 1A serotonin receptors or beta-adrenoceptors do not seem to be involved in such a phenomenon.

Estrous cycle- and acute stress-related changes of rat ovarian immunoreactive corticotropin-releasing factor

Corticotropin-releasing factor (CRF), the major regulator of the stress response within the central nervous system, is also present at peripheral sites, including the gonads, and the gene encoding its own receptor can be finely induced in selective ovarian compartments in both control and stressful conditions during the gonadal life cycle. The present study, therefore, investigated the influence of both gonadal function and estrous cycle on the immunoreactive CRF (irCRF) contents in the immature and adult rat ovary. In addition, the effect of an acute (5 min) or chronic intermittent (twice a day for 4 days) cold swimming stress on ovarian irCRF contents was evaluated. High-performance liquid chromatography (HPLC), gel-chromatography (Sephadex G-75, 45 x 1 cm) and a direct radioimmunoassay were performed to measure irCRF ovarian contents. The HPLC elution profile of irCRF in ovarian tissues of adult rats was superimposable on that of synthetic rat/human CRF and gel-chromatograms performed according to the phase of the estrous cycle revealed higher irCRF contents at proestrus. Total irCRF ovarian content was undetectable both in control and acute stressed immature rats, while adult rats showed the highest values at proestrus (p < 0.0001). The acute stress exposure induced a significant increase (p < 0.0001) of irCRF ovarian contents only at proestrus, without affecting irCRF at the other phases of the estrous cycle. Finally, no significant changes were found in ovarian irCRF after chronic intermittent stress. The proestrus-related changes of ovarian irCRF, confirming the adult ovary as an extrahypothalamic source of CRF, may constitute a neuropeptidergic signal involved in the gonadal reproductive cycle. Furthermore, the stress-related changes of ovarian irCRF indicated that the gonad may be locally sensitive to acute stressful stimuli.

Bicuculline enhances the corticosterone secretion induced by lipopolysaccharide and interleukin-1 alpha in male rats

Lipopolysaccharide (LPS)-induced inflammatory stress activates the hypothalamus-pituitary-adrenal (HPA) function. Interleukin-I (IL-1) is one of the key factors during this event; however, the mechanisms mediating IL-1 stimulation of HPA axis are still unclear. The present study evaluated the possible involvement of gamma-aminobutyric acid (GABA) in LPS-induced activation of HPA axis in adult male rats. In addition, the possible existence of diurnal changes of LPS-induced HPA axis activity was also investigated. Bicuculline (0.8 mg/kg BW), a GABA-A receptor antagonist and GABA (1 g/kg BW) were intraperitoneally (ip) injected 15 min before LPS (2 mg/kg BW, ip) or recombinant human IL-1 alpha (microgram/rat) administration in intact rats. Control animals received an equivalent volume of 0.9% saline. Rats were sacrificed at 60 min or 90 min after LPS, or IL-1 alpha or saline injection. Plasma corticosterone levels were measured by radioimmunoassay. Results showed that pretreatment with bicuculline enhanced both LPS- and IL-1-induced corticosterone secretion; while pretreatment with GABA significantly reduced the LPS-stimulated corticosterone release (p < 0.05, vs LPS alone). The effect is dependent on the time of sampling and such effect of bicuculline or GABA was not observed when rats were stimulated in the evening. In addition, the maximal changes of plasma corticosterone following LPS administration in the evening were significantly lower than in the morning (p < 0.01). The present study provides evidence that GABA is involved, at least in part, in the neuroendocrine regulation of LPS/interleukin-1a-induced corticosterone secretion via GABA-A receptor in rats. In addition, the response of plasma corticosterone to LPS has a diurnal variation, which corresponds to a diurnal change of GABAergic modulation of the immunoneuroendocrine response.

Allopregnanolone concentration in hippocampus of prepubertal rats and female rats throughout estrous cycle

Hippocampus plays an important role in cognition, neuroendocrine function and sexual behaviour. Changes of hippocampal neuropeptide and neurotransmitter concentrations are associated to behavioural changes occurring throughout reproductive life. The present study focused the attention on the presence of a neurosteroid, 5 alpha-pregnan-3 alpha-ol-20-one (termed allopregnanolone) in hippocampus. In particular, hippocampal allopregnanolone concentration in male and female prepubertal rats and in female rats throughout estrous cycle were evaluated. Hippocampal extracts were eluted on high pressure liquid chromatography and allopregnanolone concentration was measured by radioimmunoassay. Prepubertal male and female rats (15 days old) showed highest values which significantly decreased with advancing age (25 and 60 days) (p < 0.01); the lowest hippocampal concentration of allopregnanolone was found in adult rats. Female rats on proestrus morning and afternoon showed an hippocampal allopregnanolone concentration significantly higher than on diestrus or on estrus (p < 0.01), while rats on estrus showed hippocampal allopregnanolone concentration significantly lower than during other days of estrus cycle (p < 0.01). These data indicate differences in hippocampal concentration of allopregnanolone between prepubertal and adult rats and throughout estrous cycle in female rats. This finding suggest a putative role of neurosteroids in the modulation of behavioral changes occurring throughout reproductive life.

Evidence for a role for the neurosteroid allopregnanolone in the modulation of reproductive function in female rats

The present study investigated the effect of allopregnanolone (5 alpha-pregnan-3 alpha-ol-20-one) or of passive immunoneutralization of brain allopregnanolone, the most potent steroid produced by neurons, on ovulation rate and sexual behavior in female rats. Allopregnanolone was injected intracerebroventricularly in rats on diestrus and proestrus and tests were done on estrus. The intracerebroventricular injection of allopregnanolone significantly decreased the number of oocytes collected on estrus (p < 0.01). To support a physiological involvement, antiserum to allopregnanolone was injected centrally to block the activity of the endogenous neurosteroid. When administered on diestrus and proestrus or only on proestrus, the antiserum was shown to be correlated with a significant increase (p < 0.01) in oocytes retrieved on estrus. In female rats treated with antiserum to allopregnanolone, the lordosis intensity was augmented significantly as compared to controls. Finally, the possible changes of medial basal hypothalamus concentration of allopregnanolone throughout the estrous cycle and at the time of ovulation were investigated. Hypothalamic extracts were eluted on high-pressure liquid chromatography and allopregnanolone concentration was measured by radioimmunoassay. Brain cortex was used as control tissue. Hypothalamic allopregnanolone concentration on proestrus morning and afternoon was found to be significantly lower than in the remaining phases of the estrous cycle (p < 0.01), while no significant changes were observed in brain cortex concentration of allopregnanolone. The present results suggest that hypothalamic allopregnanolone may be involved in the mechanism of ovulation, affecting hormonal and behavioral events.

Evidence for a role of neurosteroids in modulation of diurnal changes and acute stress-induced corticosterone secretion in rats

The neurosteroid allopregnanolone has been shown to be a potent ligand of gamma-aminobutyric acid (GABA)-A receptors and enhances its receptor-mediated inhibitory events. Since central GABA plays a major inhibitory role, via GABA-A receptors, in hypothalamic-pituitary-adrenal (HPA) function in rats, the present study has evaluated the effect of passive immunoneutralization of allopregnanolone on diurnal changes in corticosterone secretion and acute stress-induced corticosterone secretion in rats. In the first protocol, four groups of male rats (prepubertal, fertile, castrated adult and aged) and three groups of female rats (prepubertal, fertile at different phases of the estrous cycle and aged) were studied. Rats were injected intracerebroventricularly (i.c.v.) with 10 microliters anti-allopregnanolone serum or 10 microliters normal rabbit serum (control) 24 h before exposure to an acute cold swimming stress, and sacrificed either before stress or after 5 min stress. In the second protocol, fertile male or female rats at diestrus II were injected i.c.v. with anti-allopregnanolone serum or normal rabbit serum and sacrificed on the following day at 10.00 or 18.00. Truncal blood samples were collected for measuring plasma corticosterone. Our results showed that there was no significant difference in basal plasma corticosterone levels between antiserum-treated and control rats of both sexes. However, in male rats, central injection of antiserum to allopregnanolone significantly potentiated plasma corticosterone response to stress in prepubertal and adult fertile rats as well as in castrated rats. Likewise, in female rats, the stress response of plasma corticosterone was enhanced by passive immunoneutralization of allopregnanolone in prepubertal and fertile rats throughout the estrous cycle.(ABSTRACT TRUNCATED AT 250 WORDS)

Involvement of mu-opioid receptors in the modulation of pituitary-adrenal axis in normal and stressed rats

The availability of the most selective, high-affinity, natural opioid agonists for mu-receptors (dermorphin-DM) and delta-receptors (deltorphin-DT) has provided the possibility for in vivo studying of the role of acute and chronic activation of mu- and delta-opioid receptors on the functional activity of the hypothalamus-pituitary-adrenocortical (HPA) axis, both in basal conditions and in response to an acute stress in adult male rats. Plasma corticosterone (CS) and beta-endorphin-like-immunoreactivity (beta-EP-LI) levels were measured by specific radioimmunoassays before and after 5 and 30 minutes from the exposure to cold (3 +/- 0.5 C) water and forcing them to swim for 10 minutes (acute cold swimming stress). Acute administration of DM, the specific mu-receptor agonist, enhanced basal and stress induced plasma levels of CS and beta-EP-LI. These effects were antagonized by pretreatment with naloxone, specific mu-opioid receptor antagonist, but not by naltrindole, a delta-opioid receptor antagonist. Long-term administration of DM did not alter resting plasma levels of CS and beta-EP-LI, but significantly reduced stress-induced increase of these hormones. Both the acute and chronic administration of the DT, highly selective delta-opioid receptors agonist, failed to modify resting and stress induced hormone levels. Our present data show that DM throughout mu-opioid receptors, but not DT, modulates the response of HPA axis to acute stress in rats, increasing or decreasing the release of CS and beta-EP-LI when acutely or chronically administered, respectively.

Pituitary and ovarian interleukin-1 alpha content changes according to estrous cycle and acute stress exposure

A complex interaction between the immune and neuroendocrine systems has been established. In particular, cytokines are known to be one of the mediators of the stress response, and modulate hormone secretion by acting in the brain, pituitary and gonads. The aim of the present study is to investigate whether pituitary and ovarian interleukin-1 alpha (IL-1 alpha) content changes according to the estrous cycle. In addition, the possible pituitary and ovarian IL-1 alpha changes in rats exposed to acute (5 min) or chronic intermittent (twice a day for 4 days) cold swimming stress were studied. The IL-1 alpha content of ovarian and pituitary homogenates was measured by a sensitive and specific radioimmunoassay. Immunoreactive IL-1 alpha (irIL-1 alpha) was detectable only in ovaries collected in rats at proestrus and estrus while not in those collected at diestrus I and II. The highest values were found at proestrus. No significant changes were found in ovarian irIL-1 alpha content in rats exposed to acute or chronic intermittent stress in comparison to control rats. In the pituitary, no difference in IL-1 alpha content was found throughout the estrous cycle. Acute stress induced a significant increase in pituitary irIL-1 alpha content only at proestrus (p < 0.01), however, no significant differences were found in comparison to control rats after chronic intermittent stress. The proestrus-related changes of ovarian IL-1 alpha may constitute a hormone-dependent signal within the ovary that is involved in the ovulatory process.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute stress- or lipopolysaccharide-induced corticosterone secretion in female rats is independent of the oestrous cycle

The aim of the present study was to test whether oestrous cycle is associated with the hypothalamus-pituitary-adrenal (HPA) axis function. Thus, corticosterone secretion in rats was investigated following lipopolysaccharide (LPS), acute cold-swimming or ether stress or synthetic corticotrophin-releasing factor (CRF) administration throughout the oestrous cycle. Moreover, plasma corticosterone response to cold-swimming stress or LPS administration also was studied at different times of day on pro-oestrus of di-oestrus-I. The following observations were obtained: the morning plasma corticosterone levels in control rats did not differ with the stage of the oestrous cycle; plasma corticosterone levels increased significantly following LPS administration (2 mg/kg, ip) or following acute exposure to cold (4 degrees C)-swimming or ether stress. However, this increase in plasma corticosterone levels was not related to the stage of the oestrous cycle; synthetic CRF injection induced an increase in plasma corticosterone levels constant on di-oestrus-I and pro-oestrus; plasma corticosterone response to LPS administration or acute cold-swimming stress showed diurnal changes, with the lowest values at 18.00 h, which was independent of the oestrous cycle. By showing the unchanged corticosterone response to LPS, to acute stress and to exogenous CRF throughout the oestrous cycle, and the independence of the diurnal pattern of stress response on the oestrous cycle, the present study suggests that the oestrous cycle has no influence on the HPA activity under the present experimental conditions in rats.