Design, synthesis, and biological evaluation of naphthoylamide derivatives as inhibitors of STAT3 phosphorylation

The phosphorylation of STAT3 plays a critical physiological role in the proliferation of rectal cancer. Hence, inhibiting STAT3 phosphorylation is an effective anticancer approach. In this work, we designed a novel 5-R'-1-naphthylmethylamide scaffold as a small molecule inhibitor of STAT3 phosphorylation. The results showed that 3D and 4D have exceptional inhibitory ability against three different colorectal cancer (CRC) cell lines, and can induce apoptosis of CRC cells by inhibiting STAT3 phosphorylation, while having no killing effect on normal human cells. 3D and 4D can inhibit STAT3 phosphorylation in a time- and concentration-dependent manner, and also inhibit the nuclear translocation of interleukin (IL)-6-induced STAT3. In the in vivo tumor model research, 4D significantly reduced the tumor volume of mice and had no drug toxicity on other organ tissues. Furthermore, molecular docking studies revealed that 3D and 4D had greater binding free energy when interacting with the STAT3 SH2 structural domain, and could establish H-π interaction modes. Dynamic simulation studies indicated that both compounds were able to bind tightly to STAT3.

EXOSC10 is a novel hepatocellular carcinoma prognostic biomarker: a comprehensive bioinformatics analysis and experiment verification

Background

Hepatocellular carcinoma (HCC) is a common malignant tumor. There are few studies on EXOSC10 (exosome component 10) in HCC; however, the importance of EXOSC10 for HCC remains unclear.

Methods

In the study, the prognosis value of EXOSC10 and the immune correlation were explored by bioinformatics. The expression of EXOSC10 was verified by tissue samples from clinical patients and in vitro experiment (liver cancer cell lines HepG2, MHCC97H and Huh-7; normal human liver cell line LO2). Immunohistochemistry (IHC) was used to detect EXOSC10 protein expression in clinical tissue from HCC. Huh-7 cells with siEXOSC10 were constructed using lipofectamine 3000. Cell counting kit 8 (CCK-8) and colony formation were used to test cell proliferation. The wound healing and transwell were used to analyze the cell migration capacity. Mitochondrial membrane potential, Hoechst 33342 dye, and flow cytometer were used to detect the change in cell apoptosis, respectively. Differential expression genes (DEGs) analysis and gene set enrichment analysis (GSEA) were used to investigate the potential mechanism of EXOSC10 and were verified by western blotting.

Results

EXOSC10 was highly expressed in tissues from patients with HCC and was an independent prognostic factor for overall survival (OS) in HCC. Increased expression of EXOSC10 was significantly related to histological grade, T stage, and pathological stage. Multivariate analysis indicated that the high expression level of EXOSC10 was correlated with poor overall survival (OS) in HCC. GO and GSEA analysis showed enrichment of the cell cycle and p53-related signaling pathway. Immune analysis showed that EXOSC10 expression was a significant positive correlation with immune infiltration in HCC. In vitro experiments, cell proliferation and migration were inhibited by the elimination of EXOSC10. Furthermore, the elimination of EXOSC10 induced cell apoptosis, suppressed PARP, N-cadherin and Bcl-2 protein expression levels, while increasing Bax, p21, p53, p-p53, and E-cadherin protein expression levels.

Conclusions

EXOSC10 had a predictive value for the prognosis of HCC and may regulate the progression of HCC through the p53-related signaling pathway.

DNAJ heat shock protein family member C1 can regulate proliferation and migration in hepatocellular carcinoma

Background

DNAJ heat shock protein family (Hsp40) member C1(DNAJC1) is a member of the DNAJ family. Some members of the DNAJ gene family had oncogenic properties in many cancers. However, the role of DNAJC1 in hepatocellular carcinoma (HCC) was unclear.

Methods

In this study, expression and prognostic value of DNAJC1 in HCC were analyzed by bioinformatics. Quantitative real-time PCR and Western blotting were used to verify DNAJC1 expression in liver cancer cell lines. Furthermore, immunohistochemical (IHC) was used to detect DNAJC1 expression in liver cancer tissues. Subsequently, the effect of DNAJC1 on the proliferation, migration, invasion and apoptosis of HCC cells was detected by knocking down DNAJC1. Finally, gene set enrichment analysis (GSEA) was used to investigate the potential mechanism of DNAJC1 and was verified by Western blotting.

Results

DNAJC1 was highly expressed in HCC and was significantly associated with the prognosis of patients with HCC. Importantly, the proliferation, migration and invasion of Huh7 and MHCC97H cells were inhibited by the knockdown of DNAJC1 and the knockdown of DNAJC1 promoted Huh7 and MHCC97H cell apoptosis. Furthermore, compared to the negative control group, DNAJC1 knockdown in Huh7 and MHCC97H cells promoted the expression of p21, p53, p-p53(Ser20), Bax and E-cadherin proteins, while inhibiting the expression of PARP, MMP9, Vimentin, Snai1, Bcl-2 and N-cadherin proteins.

Conclusions

DNAJC1 had a predictive value for the prognosis of HCC. Knockdown of DNAJC1 may inhibit HCC cell proliferation, migration and invasion and promote the HCC cell apoptosis through p53 and EMT signaling pathways.

Design, Synthesis, and Molecular Docking Study of Novel 3-Cyanopyridine Derivatives for the Anti-Cancer Drug Target Survivin Protein

Survivin is an important member of the antiapoptotic protein family and controls the cell's life cycle. Overexpression of survivin in tumor cells leads to inhibition of apoptosis, thus contributing to cancer cell proliferation. The largest binding pocket in the survivin dimer was located in the BIR domain. The key to the efficacy of 3-cyanopyridines was their surface interaction with the survivin amino acid Ile74.

METHODS

Through the optimization of the 3-cyanopyridine, 29 new compounds with a 3- Cyanopyridine structure were designed, synthesized, and characterized by NMR, IR, and mass spectrometry. The antitumor activity of the compounds in vitro was detected by the MTT method.

RESULTS

In vitro anti-tumor experiments showed that some compounds exhibited good anti-cancer effects. The IC₅₀ values of the compound 2-amino-6-(2,4-difluorophenyl)-4-(4-hydroxyphenyl) nicotinonitrile (10n) against human liver cancer (Huh7), human glioma (U251), and human melanoma (A375) cells were 5.9, 6.0 and 7.2 μM, respectively. The IC₅₀ values of the compound 6-(2,4-difluorophenyl)- 4-(4-hydroxyphenyl)-2-oxo-1,2-dihydropyridine-3-carbonitrile (9o) against Huh7, U251 and A375 cells were 2.4, 17.5 and 7.2 μM, respectively, which were better than those of 10- hydroxycamptothecin and 5-fluorouracil. Analysis of the results of molecular dynamics simulation established that the BIR domain is the optimal binding site on the survivin protein, and the fingerprints of the eight most active compounds and the molecular docking to the survivin protein are analyzed.

CONCLUSION

3-Cyanopyridine is an excellent backbone for antitumor lead compounds, 10n and 9o, as derivatives of 3-Cyanopyridine are excellent survivin protein-targeting inhibitors worthy of further study. The key factor in inhibiting survivin protein through the action of amino acid Ile74.

Study on the biological mechanism of urolithin a on nasopharyngeal carcinoma in vitro

CONTEXT

Urolithin A (UroA) can inhibit the growth of many human cancer cells, but it has not be reported if UroA inhibits nasopharyngeal carcinoma (NPC) cells.

OBJECTIVE

To explore the inhibitory effect of UroA on NPC and potential mechanism in vitro.

MATERIALS AND METHODS

RNA-sequencing-based mechanistic prediction was conducted by comparing KEGG enrichment of 40 μM UroA-treated for 24 h with untreated CNE2 cells. The untreated cells were selected as control. After NPC cells were treated with 20-60 μM UroA, proliferation, migration and invasion of were measured by colony formation, wound healing and transwell experiments. Apoptosis, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) were measured by flow cytometry, Hoechst 33342, Rhodamine 123, JC-1 staining and ROS assay methods, respectively. Gene and protein expression were measured by RT-qPCR and Western blotting assay.

RESULTS

RNA-sequencing and KEGG enrichment revealed UroA mainly altered the ECM receptor interaction pathway. UroA inhibited cells proliferation, epithelial-mesenchymal-transition pathway, migration and invasion with IC₅₀ values of 34.72 μM and 44.91 μM, induced apoptosis, MMP depolarization and increase ROS content at a concentration of 40 μM. UroA up-regulated E-cadherin, Bax/Bcl-2, c-caspase-3 and PARP proteins, while inhibiting COL4A1, MMP2, MMP9, N-cadherin, Vimentin and Snail proteins at 20-60 μM. Moreover, co-treatment of UroA (40 μM) and NAC (5 mM) could reverse the effect of UroA on apoptosis-related proteins.

DISCUSSION AND CONCLUSIONS

RNA-sequencing technology based on bioinformatic analyses may be applicable for studiying the mechanism of drugs for tumour treatment.

Oral oligofructose challenge reduces expression of glucose transport-1 and 5'-adenosine monophosphate-activated protein kinase in lamellar wall of Holstein heifer claw

The laminar tissue of bovine laminitis may undergo energy failure. The expression of glucose transport protein-1 (GLUT-1) and 5'-adenosine monophosphate-activated protein kinase (AMPK) affects the energy metabolism of digital laminar tissue. This study aimed to determine the expression of glucose uptake and AMPK in laminar wall corium of Holstein heifer claw by oral administration of oligofructose. A total of twelve clinically healthy Holstein heifers were selected and divided into two groups, including control (CON, n = 6) and experimental (OF, n = 6) groups. The heifers of OF group were given 17 g/kg BW oligofructose dissolved in water (20 mL/kg BW) and the heifers of CON group were given water only (20 mL/kg BW). The laminar tissues were collected after euthanasia. The amount of protein and transcript expression of AMPK and GLUT-1 were determined by western blot and quantitative reverse transcription-polymerase chain reaction (qRT-PCR), respectively. Expressions of phosphoenolpyruvate carboxy-kinase (PEPCK), receptor-c coactivator1-α (PGC-1α) and peroxisome proliferator-activated receptor-γ (PPAR-γ) were determined by qRT-PCR. The heifers of OF group showed no significant change in the expression and concentration of AMPK. The phosphor-(Thr172) AMPK and GLUT-1 were significantly decreased, while the gene contents of PPAR-γ and PGC-1α were significantly increased. The activation of AMPK and GLUT-1 in digital laminar tissues of heifers was inhibited, which may contribute to digital laminar tissue damage.

Xanthomicrol suppresses human hepatocellular carcinoma cells migration and invasion ability via Μu-opioid receptor

BACKGROUND

Xanthomicrol is one of the methoxylated flavones and a promising cancer chemopreventive agent, but its anti-migration and anti-invasion ability on human hepatocellular carcinoma (HCC) remains unknown.

OBJECTIVES

This study aims to explore Xanthomicrol's effects on migration and invasion ability of the human HCC Huh7 cell line.

METHODS

Viability of Huh7 cells was measured by cell counting kit-8 (CCK8) assay. Cell apoptosis was assayed with flow cytometry analysis. The ability of migration and invasion of Huh7 cells was then detected through Transwell assays. Epithelial-mesenchymal transition (EMT)-related proteins were also detected through Western blot.

KEY FINDINGS

Xanthomicrol inhibits the migration and invasion of Huh7 cells. The overexpression of Μu-opioid receptor (MOR) increases Huh7 cells' proliferation and enhances migration and invasion ability, while xanthomicrol treatment decreases the expression of MOR. Moreover, xanthomicrol can reverse migration, invasion and EMT-related protein expression by overexpressed MOR.

CONCLUSIONS

These results suggest that xanthomicrol is a potential MOR antagonist, and it possesses potent anti-migration and anti-invasion ability on Huh7 cells.

6-Shogaol from ginger shows anti-tumor effect in cervical carcinoma via PI3K/Akt/mTOR pathway

PURPOSE

6-Shogaol, an active phenolic compound from ginger (Zingiber officinale), can inhibit the growth of a variety of human cancer cells. Nevertheless, its underlying molecular mechanisms in cervical cancer remain unclear. In this study, we systematically examine the inhibitory effect of 6-shogaol on cervical cancer in vitro and in vivo.

METHODS

Cell proliferation was assessed by CCK8 assay and colony formation assay in HeLa and SiHa cells. We analyzed cell cycle and apoptosis through flow cytometry. GFP-LC3 puncta and transmission electron microscopy were used to observe autophagic bodies. Wound-healing assay and transwell assay were used for evaluating the migration of cells. Western blot was applied to detect protein expression levels.

RESULTS

6-Shogaol could suppress cell proliferation and migration, cause cell cycle arrest in the G2/M phase in HeLa and SiHa cells. Moreover, 6-shogaol triggered the apoptosis process through the mitochondrial pathway by downregulating the expression levels of p-PI3K, p-Akt and p-mTOR. Further research indicated that the induction of apoptosis by 6-shogaol was remarkably decreased after the treatment of ROS scavenger and PI3K agonist. Additionally, 6-shogaol increased the number of LC3-positive puncta and autophagic bodies per cell in both HeLa and SiHa cells. Pretreatment of cells with Bafilomycin A1, an autophagy inhibitor, accelerated 6-shogaol mediated cell apoptosis, suggesting that induction of autophagy by 6-shogaol is suppressive to apoptosis. Furthermore, in vivo data revealed that 6-shogaol significantly inhibited tumor growth and cell proliferation in tumor tissues.

CONCLUSION

These findings suggested that 6-shogaol could be developed as a functional food ingredient, which is potentially used as therapeutic agents for patients with cervical cancer.

[Clinical application of the gasless unilateral axillary approach in endoscopic thyroid surgery]

Objective: To investigate the efficacy, safety and advantages of gasless unilateral axillary approach (GUAA) in endoscopic thyroid surgery. Methods: A total of 334 patients who underwent the GUAA endoscopic thyroid surgery (GUAA group) or conventional open thyroid surgery (OS group) in the Department of Head and Neck Surgery of Zhejiang Cancer Hospital from January 2017 to June 2018 were retrospectively analyzed. There were 45 males and 289 females, aged from 12 to 72 years old, of whom 139 patients were assigned to GUAA group and 195 patients to OS group. Pathological results included papillary thyroid carcinoma (282 cases), nodular goiter (41 cases) and thyroid adenoma (11 cases). Surgical exploration development curve of GUAA group was drawn and was divided into two parts: the technical exploration stage and the technical stable stage. Surgical efficiency, incidences of complications, and incision satisfaction were compared between GUAA group in technical stable stage and OS group. SPSS 25.0 software was adopted for statistical analysis. Results: The mean age in GUAA group was younger than that in OS group, with a significant difference [(35.3±9.5) years vs. (48.1±10.6) years, t=11.31, P<0.01]. The cases in the endoscope group were divided into technical exploration stage for 51 cases and technical stable stage for 88 cases according to the exploration and development curve. In unilateral radical thyroidectomy and unilateral thyroid lobectomy, the mean operation time [(90.6±18.6) min and (93.5±22.0) min] and postoperative drainage volumes [(121.5±87.6) ml and (155.5±69.1) ml] of GUAA group in the stable stage were more than those of OS group [(61.6±15.6) min and (46.5±8.4) min] and [(93.2±42.3) ml and (78.9±48.7) ml]. The difference was statistically significant (t=12.28, 7.23, 3.35 and 3.05 respectively, all P<0.05), but there were no significant differences in surgical bleeding volumes between two groups [(12.7±6.8) ml vs. (13.5±7.7) ml, t=0.74, P>0.05 and (16.3±14.1) ml vs. (11.9±5.1) ml, t=1.05, P>0.05]. Compared with OS group, GUAA group had the lower incidence of anterior cervical discomfort during swallowing (2.3% vs. 29.2%, P<0.01) and the higher incision satisfaction score (1.1±0.5 vs. 2.8±0.7, t=21.12, P<0.01), however, GUAA group had the higher incidence of supraclavicular (or infraclavicular) numbness after surgery (5.7% vs. 0, P<0.01). And there was no significant difference in the incidences of temporary recurrent laryngeal nerve injury, bleeding, hematoma, infection, lymphatic leakage or chylous leakage after surgery between two groups (P>0.05). Conclusion: GUAA endoscopic thyroid surgery is a safe method with high cosmetic satisfaction.

α-Cyperone inhibits the proliferation of human cervical cancer HeLa cells via ROS-mediated PI3K/Akt/mTOR signaling pathway

Cervical cancer is the fourth leading killer of female cancer patients worldwide. Each year more than half a million women are diagnosed with cervical cancer and the disease results in over 300, 000 deaths. α-Cyperone is known as the principal active ingredient in the Cyperus rotundus (Family: Cyperaceae). However, the effects of α-Cyperone on cancers, especially on cervical cancer, are yet to be explored. In the present study, the underlying mechanism of the anti-tumor activity of α-Cyperone against HeLa cells was investigated. The results showed that α-Cyperone inhibited proliferation and induced apoptosis in HeLa cells. Mechanistically, α-Cyperone promoted HeLa cells apoptosis via a mitochondrial apoptotic pathway, which was proved by increased level of intracellular reactive oxygen species (ROS) and upregulated expression of cytochrome c, cleaved caspase-3, PARP, and Bax. Further RNA-sequencing revealed α-Cyperone inhibited the activation of PI3K/Akt/mTOR signaling pathway in HeLa cells, which confirmed by PI3K inhibitor and agonist. The PI3K inhibitor (LY294002) synergized with α-Cyperone in arresting the growth of HeLa cells, whereas the PI3K agonist (IGF-1) abrogated such an effect. Interestingly, the expression of PD-L1 was attenuated by both α-Cyperone and LY294002, while the supplement of IGF-1 rescued the low expression of PD-L1. In conclusion, our results reveal that the inhibitory effect of α-Cyperone on HeLa cell growth is triggered via the ROS-mediated PI3K/Akt/mTOR signaling pathway and closely related to a decline in the PD-L1 expression.

14,15β-dihydroxyklaineanone inhibits HepG2 cell proliferation and migration through p38MAPK pathway

OBJECTIVES

Eurycoma longifolia Jack (Simaroubaceae) is commonly distributed in the Southeast Asia and Indo China, which has been shown to possess antianxiety, antibacterial, anticancer, antifungal, anti-inflammatory, antimalarial and antioxidant biological activities. 14,15β-dihydroxyklaineanone is a diterpene isolated from E. longifolia Jack, which is cytotoxic against human lung cancer and human breast cancer cell lines. However, the effects and underlying mechanisms of 14,15β-dihydroxyklaineanone on hepatocellular carcinoma remain unknown.

METHODS

Cell viability assay and colony formation assay were used to measure HepG2 cell proliferation. Flow cytometry was used to analyse cell cycle and apoptosis. Wound-healing assay and transwell assay were used to observe cells migration. RNA sequencing and the enrichment of differentially expressed genes (DEGs) in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were used to find and determine underlying pathways.

KEY FINDINGS

We found that 14,15β-dihydroxyklaineanone inhibited the growth and migration of HepG2 cells but did not induce cell apoptosis. 14,15β-dihydroxyklaineanone induced S cell cycle arrest by downregulating the expression levels of cyclin A, p-CDK2, cyclin B1, p21, E2F-1 and PCNA. In addition, RNA sequencing showed that 14,15β-dihydroxyklaineanone regulated MAPK pathway by increasing the expression levels of phosphor-p38. Downregulating of p38 via both p38 inhibitor (SB203580) and p38-siRNA could antagonize the inhibition of cell proliferation and migration and reverse the changes in p-p38, E-cadherin, N-cadherin and PCNA expression induced by 14,15β-dihydroxyklaineanone treatment.

CONCLUSIONS

14,15β-dihydroxyklaineanone inhibited cell proliferation and migration through regulating p38 MAPK pathway in HCC cells.

A Genetic Variant of miR-34a Contributes to Susceptibility of Ischemic Stroke Among Chinese Population

miRNAs are small non-coding RNAs modulating gene expression, and variants in miRNA genes are involved in the pathogenesis of ischemic stroke (IS). However, the effect of miR-34a polymorphisms on IS susceptibility has rarely been reported. In the present study, we investigated the association between rs12128240, rs2666433, and rs6577555 of the miR-34a gene and IS susceptibility. Snapshot assay was used to detect miR-34a polymorphisms in 548 IS patients and 560 controls. Relative expression of miR-34a was measured by quantitative real-time PCR. We found that rs2666433 was associated with a significantly increased risk of IS (AA vs. GG: OR = 1.61, 95% CI = 1.05-2.52, P = 0.031; AA vs. GG+GA: OR = 1.58, 95% CI = 1.05-2.45, P = 0.026). For the IS subtypes, rs2666433 was associated with large artery atherosclerosis (AA vs. GG: OR = 2.09, 95% CI = 1.16-3.51, P = 0.007; AA vs. GG+GA: OR = 2.02, 95% CI = 1.15-3.33, P = 0.007; A vs. G: OR = 1.36, 95% CI = 1.07-1.81, P = 0.021). Additionally, the level of miR-34a was significantly up-regulated in IS patients compared to the controls (P < 0.001), and patients with rs2666433 AA genotype had a higher level of miR-34a than those with GG+GA genotypes (P < 0.001). Furthermore, increased level of homocysteine was observed in IS patients compared to the controls (P < 0.001), especially in patients carrying the rs2666433AA genotype compared to those carrying the rs2666433 GG+GA genotypes (P < 0.001). However, no significant association between rs12128240 or rs6577555 and IS was found. Collectively, our study found the association between miR-34a polymorphisms and the risk of IS among the Chinese population. The results may provide an explanation for etiology of IS and a potential biomarker or therapeutic target for IS. HIGHLIGHTS-MiR-34a rs2666433 polymorphism was associated with an increased risk of ischemic stroke.-The level of miR-34a was significantly up-regulated in ischemic stroke patients compared with controls, and patients with rs2666433 AA genotype had a higher level miR-34a than those with GG+GA genotypes.-Furthermore, increased level of homocysteine was showed in IS patients compared to controls, and in patients carrying the rs2666433AA compared to those carrying the rs2666433 GG+GA.

[Voxel-based morphometry (VBM) MRI analysis of gray matter in patients with occupational noise-induced hearing loss]

Objective: To investigate the changes of brain gray matter volume in patients with occupational noise-induced hearing loss by voxel based morphometry (VBM) . Methods: 16 age-and education-matched healthy controls and 42 patients with occupational noise induced hearing loss, including 27 in mild group and 15 in severe group, received MRI 3D-FSPGR sequence T1WI sagittal scan, and then underwent VBM of brain gray matter volume data analysis. Results: The brain gray matter volume of the left occipitotemporal lateral gyrus, the anterior cingulate gyrus, the bilateral angular gyrus, the precuneus and the near midline area of cerebellum differed between experimental group and control group (P<0.01) . Conclusion: The volume of gray matter in specific brain areas of patients with occupational noise-induced hearing loss was changed, and the effect of noise on brain structure was revealed from the perspective of imaging.

Design, synthesis and antitumor activity of steroidal pyridine derivatives based on molecular docking

With steroid as a carrier nucleus and introducing a pyridine heterocycle as a pharmacophore on the D ring, a series of steroidal pyridine derivatives were designed and studied for their antitumor activity by molecular docking software. The compounds were synthesized as small molecule inhibitors and studied as anticancer agents. The synthesis of the analogs was performed in a one-pot multi-component reaction and the corresponding compounds were screened in vitro for their antitumor activity. Four adherently growing cancer cell lines were used and arranged before dosing. Among all compounds screened for their antitumor activity, compounds 2f and 2p were found to be the most active. Here, the most obvious changes in the morphology of the treated cells could be observed.

Immunomodulatory and antioxidant effects of total flavonoids of Spatholobus suberectus Dunn on PCV2 infected mice

Oxidative stress plays an important role in the pathogenesis of virus infection and antioxidants are becoming promising candidates as therapeutic agents. This study is designed to investigate the effect of total flavonoids of Spatholobus suberectus Dunn (TFSD) on oxidative stress in mice induced by porcine circovirus type 2 (PCV2) infection. The PCV2 infection leads to significant decrease in thymus and spleen indices, elevation of xanthine oxidase (XOD) and myeloperoxidase (MPO) activities, reduction in GSH level and GSH to GSSG ratio and decline of superoxide dismutase (SOD) activity, indicating the formation of immunosuppression and oxidative stress. TFSD treatment recovered the alteration of viscera index, antioxidant content and activities of oxidative-associated enzymes to a level similar to control. Our findings suggested that PCV2 induced immunosuppression and oxidative stress in mice and TFSD might be able to protect animals from virus infection via regulation of immune function and inhibition of oxidative stress.

Increased human epididymis protein 4 in benign gynecological diseases complicated with chronic renal insufficiency patients

We examined the serum concentration of human epididymis protein (HE4) in patients with benign gynecological diseases complicated with chronic renal deficiency and its significance in the differential diagnosis of benign and malignant gynecological diseases. Serum HE4 and cancer antigen 125 concentrations were detected by chemiluminescence. Clinically or pathologically confirmed gynecological diseases were grouped and retrospectively analyzed, including 50 cases of gynecological benign diseases, 35 cases of non-mucinous epithelial ovarian carcinoma, 36 cases of endometrial adenocarcinoma, 15 cases of gynecological benign diseases patients complicated with chronic renal deficiency, 15 cases of gynecological diseases without chronic renal deficiency, and 30 normal controls. Serum HE4 values in the ovarian cancer group, endometrial cancer group, gynecological benign diseases with chronic renal deficiency group, and chronic renal deficiency group were significantly increased compared with the benign gynecological diseases and normal control groups, showing a significant difference (P < 0.001). A comparison of 4 groups with high HE4 showed that the HE4 level in the 2 groups with renal deficiency were higher than those in the ovarian cancer and endometrial cancer groups, but the difference was not significant (P > 0.05); there was no significant difference between 2 groups with renal deficiency (P > 0.05). Serum concentration of HE4 was high in patients with chronic renal deficiency, which should be distinguished during differential diagnosis of gynecological benign and malignant tumors in patients with chronic renal deficiency to avoid misdiagnosis.

Effects of propofol on lipopolysaccharide-induced expression and release of HMGB1 in macrophages

This study aimed to determine the effects of different concentrations of propofol (2,6-diisopropylphenol) on lipopolysaccharide (LPS)-induced expression and release of high-mobility group box 1 protein (HMGB1) in mouse macrophages. Mouse macrophage cell line RAW264.7 cells were randomly divided into 5 treatment groups. Expression levels of HMGB1 mRNA were detected using RT-PCR, and cell culture supernatant HMGB1 protein levels were detected using enzyme-linked immunosorbent assay (ELISA). Translocation of HMGB1 from the nucleus to the cytoplasm in macrophages was observed by Western blotting and activity of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in the nucleus was detected using ELISA. HMGB1 mRNA expression levels increased significantly in the cell culture supernatant and in cells after 24 h of stimulating RAW264.7 cells with LPS (500 ng/mL). However, HMGB1 mRNA expression levels in the P2 and P3 groups, which received 500 ng/mL LPS with 25 or 50 μmol/mL propofol, respectively, were significantly lower than those in the group receiving LPS stimulation (P<0.05). After stimulation by LPS, HMGB1 protein levels were reduced significantly in the nucleus but were increased in the cytoplasm (P<0.05). Simultaneously, the activity of NF-κB was enhanced significantly (P<0.05). After propofol intervention, HMGB1 translocation from the nucleus to the cytoplasm and NF-κB activity were inhibited significantly (each P<0.05). Thus, propofol can inhibit the LPS-induced expression and release of HMGB1 by inhibiting HMGB1 translocation and NF-κB activity in RAW264.7 cells, suggesting propofol may be protective in patients with sepsis.

Association between metabolic syndrome and vascular endothelium dysfunction in children and adolescents

We aimed at investigating the association between metabolic syndrome (MS) and vascular endothelial cell dysfunction (ECD) in children and adolescents. Sixty children (30 obese children and 30 children with MS) were included in this retrospective analysis. Thirty healthy subjects were randomly selected as the control group. A series of indices/biomarkers known to be related to MS/ECD were determined using ELISA. Correlations between the variables measured were analyzed. Compared with the control group, PAI-1, vWF, VE-cad, TM, and VEGF were significantly increased in the MS group (P < 0.05). Adolescents in the obese group had significantly increased levels of serum PAI-1, VE-cad, TM, and VEGF as compared with the control group (P < 0.05). Further, vWF in the obese and control groups did not differ significantly (P = 0.556). Our results suggest that ECD is correlated with MS in children and adolescents. Pathophysiological changes of the vascular endothelium may exist in obese children who have yet to develope MS. PAI-1, vWF, VE-cad, TM, and VEGF could be used as biomarkers for predicting ECD. ECD that develops in patients with MS may be associated with obesity, elevated blood lipid, elevated blood glucose, and higher blood pressure.

LiSr4(BO3)3:Ce3+ phosphor as a new material for ESR dosimetry

LiSr4(BO3)3:0.01Ce(3+) phosphor was investigated to assess its potential as a material for measurements of radiotherapeutic doses with electron spin resonance (ESR). The ESR spectrum of the phosphor irradiated with (60)Co features five ESR signals. An isochronal annealing experiment has shown that the strongest of these signals is associated with the same trap center as the 473 K peak on the TL glow curve of this material. The dose-response is linear in the studied range from 0.89 to 90.30 Gy. Fading of the signal was also investigated.

Oral administration of docosahexaenoic acid activates the GDNF-MAPK-CERB pathway in hippocampus of natural aged rat

CONTEXT

Docosahexaenoic acid (DHA) is one of the critical fatty acids for optimal health, which affect the expression of nerve growth factor and brain-derived neurotrophic factor in brain.

OBJECTIVE

This study investigates whether DHA supplementation affects lipid peroxidation and activates the glial-derived neurotrophic factor (GDNF)-mitogen-activated protein kinase pathway (MAPK pathway) in hippocampus of natural aged rat.

MATERIALS AND METHODS

Rats were randomly divided into four groups; DHA was orally administered at 80 and 160 mg/kg/day to 24-month female rats for 50 days. The antioxidant parameters and GDNF-GDNF family receptor α-1 (GFRα1)-tyrosine-protein kinase receptor (RET)-MAPK-cyclic AMP response element-binding protein (CERB) pathway were assayed in natural aged rat's hippocampus.

RESULTS AND DISCUSSION

The results demonstrated that DHA supplementation significantly increased the activities of superoxide dismutase (SOD) by 37.39 and 57.69%, glutathione peroxidase (GSH-Px) by 27.62 and 32.57% decreased TBARS level by 28.49 and 49.05%, respectively, but did not significantly affect catalase (CAT), in hippocampus, when compared with the aged group. DHA supplementation in diet resulted in an increase of DHA level in hippocampus. Furthermore, we found that DHA supplementation markedly increased the levels of GDNF and GFRα1 and the phosphorylation of RET, and led to the activation of the MAPK pathway in hippocampus tissue.

CONCLUSION

DHA supplementation can change fatty acids composition, improve antioxidant parameters and activate the GDNF-MAPK pathway in natural aged rat's hippocampus.

Tissue distribution, expression, and antimicrobial activity of Anas platyrhynchos avian β-defensin 6

In this study, a novel avian β-defensin (AvBD) was isolated from the Chaohu duck. The complete nucleotide sequence of the gene contained a 204-bp open reading frame that encoded 67 amino acids (aa), including a signal peptide of 20 aa, a propiece of 5 aa, and a mature peptide of 42 aa. The homology, characterization, and comparison of this gene with AvBD from other avian species confirmed that it was duck AvBD6. Also, the preproprotein of AvBD6 from chicken, goose, and duck was highly conserved with 100% aa homology. The AvBD6 mRNA was widely expressed in the investigated tissues of healthy 5-mo-old ducks, with the exception of the skin, kidney, and bursa. The AvBD6 mRNA was highly expressed in the spleen, lung, stomach, tongue, and egg yolk, successively; moderately expressed in the bone marrow and liver; and expressed to lower degrees in the trachea, heart, intestine, muscle, esophagus, and testis. We produced recombinant AvBD6 by expressing the gene in Escherichia coli. The yield of soluble glutathione S-transferees (GST)-AvBD6 in the inclusion bodies increased significantly as the incubation temperature was decreased from 37 to 30°C. As expected, the GST-AvBD6 exhibited strong bactericidal properties [minimum inhibitory concentration (MIC) = 0.5 to 2 μM] against the Aeromonas veronii biovar sobria strain BJCP-5, E. coli, and Enterococcus faecalis [ATCC 29212); it possessed medium bactericidal properties (MIC = 4 to 8 μM) against Staphylococcus aureus, Salmonella enteritidis, Pseudomonas aeruginosa (ATCC 27853), and Bacillus subtilis (CMCC 63501;; and it possessed low bactericidal properties (MIC = 16 μM) against Candida albicans (ATCC 10231). Additionally, the antimicrobial activity of GST-AvBD6 proved to be the same as that of synthetic AvBD6. The A. veronii biovar sobria strain BJCP-5 cells that were treated with GST-AvBD6 showed lysis and shrinkage under scanning electron microscopy. The mechanisms of AvBD6-mediated killing of A. veronii biovar sobria involved both cell lysis and nonlysis. Our results indicate that AvBD6 plays an important role in the innate immunity of the Chaohu duck.

Properties and therapeutic potential of transient receptor potential channels with putative roles in adversity: focus on TRPC5, TRPM2 and TRPA1

Mammals contain 28 genes encoding Transient Receptor Potential (TRP) proteins. The proteins assemble into cationic channels, often with calcium permeability. Important roles in physiology and disease have emerged and so there is interest in whether the channels might be suitable therapeutic drug targets. Here we review selected members of three subfamilies of mammalian TRP channel (TRPC5, TRPM2 and TRPA1) that show relevance to sensing of adversity by cells and biological systems. Summarized are the cellular and tissue distributions, general properties, endogenous modulators, protein partners, cellular and tissue functions, therapeutic potential, and pharmacology. TRPC5 is stimulated by receptor agonists and other factors that include lipids and metal ions; it heteromultimerises with other TRPC proteins and is involved in cell movement and anxiety control. TRPM2 is activated by hydrogen peroxide; it is implicated in stress-related inflammatory, vascular and neurodegenerative conditions. TRPA1 is stimulated by a wide range of irritants including mustard oil and nicotine but also, controversially, noxious cold and mechanical pressure; it is implicated in pain and inflammatory responses, including in the airways. The channels have in common that they show polymodal stimulation, have activities that are enhanced by redox factors, are permeable to calcium, and are facilitated by elevations of intracellular calcium. Developing inhibitors of the channels could lead to new agents for a variety of conditions: for example, suppressing unwanted tissue remodeling, inflammation, pain and anxiety, and addressing problems relating to asthma and stroke.

Meta-analysis of epidemiological studies of association of P53 codon 72 polymorphism with bladder cancer

Although there have been many studies investigating a possible association between p53 codon 72 polymorphism and risk of bladder cancer, the results have been inconsistent. We conducted a meta-analysis of six epidemiological studies, which included 597 bladder cancer cases and 731 controls. Patients with bladder cancer had a significantly lower frequency of Pro/Arg [odds ratio (OR) = 0.80, 95% confidence interval (CI) = 0.64-0.99], when compared to controls. Stratifying for race, we found that among Caucasians, patients with bladder cancer had a significantly higher frequency of Arg/Arg (OR = 1.64, 95%CI = 1.18-2.28) and a lower frequency of Pro/Arg (OR = 0.62, 95%CI = 0.44-0.86), compared to controls. Stratifying various studies by the stage of bladder cancer, we found that invasive bladder cancers had a significantly lower frequency of Arg/Arg (OR = 0.58, 95%CI = 0.36-0.93) and a higher frequency of Pro/Arg (OR = 0.62, 95%CI = 0.44-0.86) than did non-invasive bladder cancers. No significant association was found between this genotype and human papilloma virus. Based on our meta-analysis, we suggest that p53 codon 72 polymorphism is associated with bladder cancer and that genotypic distribution of this polymorphism varies with the stage of bladder cancer.

Adsorption and oxidation of ethanol on colloid-based Pt/C, PtRu/C and Pt3Sn/C catalysts: In situ FTIR spectroscopy and on-line DEMS studies

The interaction of colloid-based, carbon supported Pt/C (40 wt%), PtRu/C (45 wt%) and Pt3Sn/C (24 wt%) catalysts with ethanol and their performance for ethanol electrooxidation were investigated in model studies by electrochemical, in situ infrared spectroscopy and on-line differential electrochemical mass spectrometry measurements. The combined application of in situ spectroscopic techniques on realistic catalysts and under realistic reaction (DEMS, IR) and transport conditions (DEMS) yields new insight on mechanistic details of the reaction on these catalysts under the above reaction and transport conditions. Based on these results, the addition of Sn or Ru, though beneficial for the overall activity for ethanol oxidation, does not enhance the activity for C-C bond breaking. Dissociative adsorption of ethanol to form CO2 is more facile on the Pt/C catalyst than on PtRu/C and Pt3Sn/C catalysts within the potential range of technical interests (<0.6 V), but Pt/C is rapidly blocked by an inhibiting CO adlayer. In all cases acetaldehyde and acetic acid are dominant products, CO2 formation contributes less than 2% to the total current. The higher ethanol oxidation current density on the Pt3Sn/C catalyst at these potentials results from higher yields of C2 products, not from an improved complete ethanol oxidation to CO2.

Overexpression of cyclooxygenase-2 correlates with tumor angiogenesis in endometrial carcinoma

The inducible enzyme cyclooxygenase-2 (COX-2) is an important mediator of angiogenesis and tumor growth. Several reports have indicated that vascular endothelial growth factor (VEGF)-positive tumors are associated with an increased amount of COX-2 protein. This study evaluated the significance of COX-2 in 34 patients with endometrial carcinoma and its relationship to angiogenesis. Immunohistochemical expression of COX-2 and VEGF was analyzed on paraffin-embedded tissue sections. Microvessel density (MVD) of endometrial carcinoma was also determined with anti-CD(34) as the label. COX-2 messenger RNA (mRNA) was analyzed by reverse transcription-polymerase chain reaction. The expression rate of COX-2 in 34 cases was 64.7% but not in control endometrium. COX-2 mRNA was higher in tumor specimens than in normal tissues. The level of COX-2 expression was higher in grade 2 tumors than in grade 3 tumors (P < 0.05). MVD was higher in COX-2-positive and VEGF-positive cases than in COX-2-negative and VEGF-negative cases (P < 0.05). The expression of COX-2 was positively correlated with the expression of VEGF and MVD (P < 0.05 and P < 0.01, respectively). The present findings suggest that overexpression of COX-2 may induce the expression of VEGF, increase angiogenesis, and enhance tumor growth.

Amino acid residues involved in gating identified in the first membrane-spanning domain of the rat P2X(2) receptor

The first hydrophobic segment of the rat P2X(2) receptor extends from residue Leu(29) to Val(51). In the rat P2X(2) receptor, we mutated amino acids in this segment and adjoining flanking regions (Asp(15) through Thr(60)) individually to cysteine and expressed the constructs in human embryonic kidney cells. Whole-cell recordings were used to measure membrane currents evoked by brief (2-s) applications of ATP (0.3-100 microM). Currents were normal except for Y16C, R34C, Y43C, Y55C, and Q56C (no currents but normal membrane expression by immunohistochemistry), Q37C (small currents), and F44C (normal current but increased sensitivity to ATP, as well as alphabeta-methylene-ATP). We used methanethiosulfonates of positive, negative, or no charge to test the accessibility of the substituted cysteines. D15C, P19C, V23C, V24C, G30C, Q37C, F44C, and V48C were strongly inhibited by neutral, membrane-permeant methanethiosulfonates. Only V48C was also inhibited by positively and negatively charged methanethiosulfonates, consistent with an extracellular position; however, accessibility of V48C was increased by channel opening. V48C could disulfide with I328C, as shown by the large increase in ATP-evoked current caused by reducing agents. The results suggest that Val(48) at the outer end of the first hydrophobic segment takes part in the gating movement of channel opening.

Identification of amino acid residues contributing to the ATP-binding site of a purinergic P2X receptor

P2X receptor subunits have intracellular N and C termini, two membrane-spanning domains, and an extracellular loop of about 280 amino acids. We expressed the rat P2X(2) receptor in human embryonic kidney cells, and used alanine-scanning mutagenesis on 30 residues with polar side chains conserved among the seven rat P2X receptor subunits. This identified a region proximal to the first transmembrane domain which contained 2 lysine residues that were critical for the action of ATP (Lys(69) and Lys(71)). We substituted cysteines in this region (Asp(57) to Asp(71)) and found that for S65C and I67C ATP-evoked currents were inhibited by methanethiosulfonates. At I67C, the inhibition by negatively charged ethylsulfonate and pentylsulfonate derivatives could be overcome by increasing the ATP concentration, consistent with a reduced affinity of ATP binding. The inhibitory action of the methanethiosulfonates was prevented by pre-exposure to ATP, suggesting occlusion of the binding site. Finally, introduction of negative charges into the receptor by mutagenesis at this position (I67E and I67D) also gave receptors in which the ATP concentration-response curve was right-shifted. The results suggest that residues close to Ile(67) contribute to the ATP-binding site.

Brilliant blue G selectively blocks ATP-gated rat P2X(7) receptors

There are few antagonists selective for subtypes of the several P2X receptors, but these are needed to identify the receptors expressed on native cells and tissues. In particular, P2X(4) and P2X(7) receptor subunits are colocalized on immune, epithelial, and exocrine gland cells, but both are relatively insensitive to suramin and pyridoxal-5-phosphate-6-azo-2',4'-disulfonic acid derivative. In this article, we show that Coomassie Brilliant Blue G selectively inhibits P2X(7) receptors with nanomolar affinity. We measured currents in response to P2X receptor activation in HEK293 cells heterologously expressing human or rat P2X(1), P2X(2), P2X(3), P2X(2/3), P2X(4), P2X(1/5), and P2X(7) receptors. Brilliant Blue G produced a noncompetitive inhibition of rat and human P2X(7) receptors with IC(50) values of 10 and 200 nM, respectively. IC(50) values for inhibition of the other receptors ranged from 2 to >30 microM; the rat and human P2X(4) receptors showed IC(50) values of >10 and 3.2 microM. Coomassie Blue G also blocked YO-PRO1 uptake and membrane blebbing, which are uniquely associated with activation of P2X(7) receptors. Thus, Brilliant Blue G is at least 1000-fold more potent at rat P2X(7) receptors than at rat P2X(4) receptors.

Regulation of cloned cardiac L-type calcium channels by cGMP-dependent protein kinase

We have studied the effect of 8-bromo-cyclic GMP (8-Br-cGMP) on cloned cardiac L-type calcium channel currents to determine the site and mechanism of action underlying the functional effect. Rabbit cardiac alpha(1C) subunit, in the presence or absence of beta(1) subunit (rabbit skeletal muscle) or beta(2) subunit (rat cardiac/brain), was expressed in Xenopus oocytes, and two-electrode voltage-clamp recordings were made 2 or 3 days later. Application of 8-Br-cGMP caused decreases in calcium channel currents in cells expressing the alpha(1C) subunit, whether or not a beta subunit was co-expressed. No inhibition of currents by 8-Br-cGMP was observed in the presence of the protein kinase G inhibitor KT5823. Substitutions of serine residues by alanine were made at residues Ser(533) and Ser(1371) on the alpha(1C) subunit. As for wild type, the mutant S1371A exhibited inhibition of calcium channel currents by 8-Br-cGMP, whereas no effect of 8-Br-cGMP was observed for mutant S533A. Inhibition of calcium currents by 8-Br-cGMP was also observed in the additional presence of the alpha(2)delta subunit for wild type channels but not for the mutant S533A. These results indicate that cGMP causes inhibition of L-type calcium channel currents by phosphorylation of the alpha(1C) subunit at position Ser(533) via the action of protein kinase G.

One year of continuous treatment with haloperidol or clozapine fails to induce a hypersensitive response of caudate putamen neurons to dopamine D1 and D2 receptor agonists

In a "blind" experimental design, the sensitivity of caudate-putamen (CPu) cells to the selective dopamine (DA) D1 receptor agonist SKF-38393 and D2 receptor agonist LY171555 (quinpirole) in rats treated with either haloperidol (HAL), clozapine or tap water for 1 year was compared using the techniques of single cell recording and microiontophoresis. Although the maximum binding value for D2 receptors was elevated in chronic HAL-treated rats, there was no sign of electrophysiological supersensitivity of CPu neurons to the selective DA D1 and D2 receptor agonists. CPu cells were subsensitive to LY-171555 in HAL-treated rats without a drug withdrawal period. This suggests that residual HAL in the rat brain actively blocked the D2 DA receptors. In contrast, in clozapine-treated rats with or without a drug withdrawal period, the sensitivity of CPu cells to either the D1 or D2 agonists was not altered. Coadministration of SKF-38393 and LY-171555 onto the CPu neurons primarily produced an additive effect and only two cells both from the HAL group showed a synergistic action. The majority of CPu cells failed to respond to iontophoretic application of CCK-8S in either the control or antipsychotic drug-treated rats. If these findings can be extended to humans, they do not support the view that tardive dyskinesia is the result of CPu DA receptor supersensitivity.

The effect of intraventricular administration of the 5-HT3 receptor agonist 2-methylserotonin on the release of dopamine in the nucleus accumbens: an in vivo chronocoulometric study

In the present study we have examined the effects of the serotonin3 (5-HT3) agonist 2-methylserotonin (2-Me-5HT) on the dopamine (DA) release in the nucleus accumbens (NAc) of rats using in vivo chronocoulometric recording. The intraventricular (i.c.v.) administration of 2-Me-5HT dose-dependently increased the DA release in the NAc. This effect was blocked by the selective 5-HT3 antagonist BRL-43694 (granisetron), but not by the 5-HT1/5-HT2 antagonist metergoline. The i.c.v. injection of 8-hydroxydipropylaminotetraline (8-OHDPAT, a selective 5-HT1a agonist) or (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI, a 5-HT2/5-HT1c agonist) failed to alter the DA release in the NAc. The increase in the DA release produced by 2-Me-5HT was abolished in animals that had received acute bilateral injections of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle. Our results suggest that the 2-Me-5HT-induced DA release in the NAc is mediated by 5-HT3 receptors. In addition, 2-Me-5HT induced effect is dependent upon the impulse flow of DA cells.

Chronic BRL 43694, a selective 5-HT3 receptor antagonist, fails to alter the number of spontaneously active midbrain dopamine neurons

In this study, we examined the effect of chronic administration of the selective 5-HT3 receptor antagonist BRL 43694 on the number of spontaneously active A9 (substantia nigra pars compacta) and A10 (ventral tegmental area) dopamine (DA) cells using the technique of extracellular single unit recording. Overall, chronic BRL 43694 (21 days, 5 mg/kg per day or 2.5 mg/kg q.i.d) failed to alter the number of spontaneously active DA cells in either area compared to saline-injected controls. Furthermore, the acute i.v. administration of BRL 43694 did not change A10 DA cell baseline firing rate. These data suggest that if BRL 43694 possesses antipsychotic activity, it is not the result of its action on midbrain DA neurons.

Electrophysiological characterization of 5-hydroxytryptamine2 receptors in the rat medial prefrontal cortex

The aim of the present study was to characterize 5-hydroxytryptamine2 (5-HT2) receptors in the rat medial prefrontal cortex (mPFc) by single cell recording and microiontophoretic techniques. This was accomplished using 5-HT2 receptor agonists 1-[2,5-dimethoxy-4-iodophenyl]-2-aminopropane [(+/-)-DOI] and 1-[2,5-dimethoxy-4-bromophenyl]-2-aminopropane [(+/-)-DOB]. DOI ejected at a low current (0.5 nA) potentiates glutamate (GLU)-induced activation of mPFc neurons and this effect is blocked by spiperone. At higher currents. DOI invariably inhibits GLU-induced neuronal activity. The microiontophoretic ejection of both DOI and DOB predominantly inhibits spontaneously active mPFc cells. The inhibitory action of DOI on spontaneously active cells is dose-dependent and is blocked by putative 5-HT2 receptor antagonists, with a rank order of potency as follows: ritanserin greater than metergoline approximately LY-53857 greater than spiperone greater than mesulergine greater than mianserin approximately ketanserin. Interestingly, ketanserin and mianserin only weakly block the effect of DOI. The suppressant action of DOI is probably not related to its interaction with 5-HT10 sites as spiperone, which has low affinity for these sites, potently blocks the effect of DOI. The suppressant effect of DOI is not blocked by other receptor antagonists such as BRL-43694 (5-HT3), (+/-)-pindolol (5HT 1a,1b, beta adrenergic, beta), prazosin (adrenergic1, alpha-1), pyrilamine (histamine1, H1), l-sulpiride (dopamine2, D2) or SR 95103 (gamma-aminobutyric acid, GABAA). Overall our results indicate that DOI predominantly inhibits mPFc cells in a direct manner and this effect is mediated by 5-HT2 receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Cholecystokinin antagonist lorglumide reverses chronic haloperidol-induced effects on dopamine neurons

Intravenous administration of the cholecystokinin (CCK) antagonist lorglumide (LORG) reversed chronic haloperidol (CHAL)-induced depolarization inactivation (DI) of dopamine (DA) cells in both the A9 and A10 areas. Moreover, microinjection of LORG, but not naloxone, directly into the medial nucleus accumbens (mNAc) dose-dependently reversed CHAL-induced effect. LORG injected into other brain regions was without effect. These results suggest that CCK receptors in the mNAc form an important link for maintaining CHAL-induced DI of DA cells and that CCK is involved in the therapeutic action of antipsychotic drugs.

Effect of catecholamine-receptor antagonists on feeding-related neuronal activity in the central amygdaloid nucleus of the monkey: a microiontophoretic study

1. Neuronal activity in the central amygdaloid nucleus (ACE) was recorded during a visually guided bar-press feeding task, and the modulatory effects of catecholaminergic blockers were investigated. 2. The feeding task had the following four phases: 1) a cue light to signal the start of bar press, 2) bar press, 3) a short cue tone followed by food delivery, and 4) ingestion reward. Of 278 cells observed, 176 (63%) increased or decreased their discharge rates in one or more phases of the feeding task. Of these, 60 (34%) responded to the cue light, 81 (46%) to the bar press, 66 (37%) to the cue tone, and 176 (100%) during the reward period. In the ingestion reward phase, firing of 128 (73%) increased and firing of 48 (27%) decreased. The reward-related response depended on the nature of food. In the trials with aversion food, some neurons increased firing (n = 6), whereas others showed opposite firing changes (n = 10). 3. The decreased firing rate during the reward period was greatly attenuated in the no-reward tasks (n = 29) and was blocked by electrophoretic application of a beta-adrenoceptive antagonist [sotalol (SOT), n = 26]. Noradrenaline (NA) application mimicked the inhibitory effect on the reward-related activity during extinction trial (n = 4). These results suggest that the decreased firing rate observed during the reward period was modulated by beta-adrenoreceptors. 4. Of 32 neurons tested, the activity of 8 (25%) and 14 (44%) were enhanced by the cue light or bar press, respectively. These effects were attenuated by electrophoretic application of a dopamine (DA) antagonist [spiperone (SPP)] but not by SOT. This indicates that dopaminergic inputs may be related to recognition of visual signals and to motor initiation during the monkey feeding paradigm.

Chronic treatment with high doses of haloperidol fails to decrease the time course for the development of depolarization inactivation of midbrain dopamine neurons

Using extracellular single unit recording techniques, we investigated the effects produced by chronic treatment with high doses of haloperidol (CHAL, 5 mg/kg/day, s.c.) on midbrain dopamine (DA) neuronal activity. This regimen of HAL treatment produced a time-dependent reduction in the number of spontaneously active DA neurons. Additionally, this dose regimen induced an irregular firing pattern in many of the remaining active DA neurons in both the ventral tegmental area (A10) and substantia nigra pars compacta (A9) regions. These effects were comparable to those obtained previously in rats treated chronically with lower doses of HAL (0.5 mg/kg/day, s.c.). However, there was a greater decrease in the number of spontaneously active DA cells detected in rats treated with high doses of HAL for three weeks compared to those receiving the low doses. On the other hand, higher doses of apomorphine (200 micrograms/kg, i.v.) were required to reverse both the reduction of DA activity and irregular discharge pattern in rats treated chronically with high doses of HAL. In conclusion, the results of the present study substantiate the view that CHAL-induced depolarization inactivation (DI) of DA neurons is a time-dependent process and chronic treatment with high doses of HAL did not shorten the time course required for the development of DI on the majority of midbrain DA neurons.