Astrocytic IP3Rs: Contribution to Ca2+ signalling and hippocampal LTP

Astrocytes regulate hippocampal synaptic plasticity by the Ca²⁺ dependent release of the N‐methyl d ‐aspartate receptor (NMDAR) co‐agonist d ‐serine. Previous evidence indicated that d ‐serine release would be regulated by the intracellular Ca²⁺ release channel IP₃ receptor (IP₃R), however, genetic deletion of IP₃R2, the putative astrocytic IP₃R subtype, had no impact on synaptic plasticity or transmission. Although IP₃R2 is widely believed to be the only functional IP₃R in astrocytes, three IP₃R subtypes (1, 2, and 3) have been identified in vertebrates. Therefore, to better understand gliotransmission, we investigated the functionality of IP₃R and the contribution of the three IP₃R subtypes to Ca²⁺ signalling. As a proxy for gliotransmission, we found that long‐term potentiation (LTP) was impaired by dialyzing astrocytes with the broad IP₃R blocker heparin, and rescued by exogenous d ‐serine, indicating that astrocytic IP₃Rs regulate d ‐serine release. To explore which IP₃R subtypes are functional in astrocytes, we used pharmacology and two‐photon Ca²⁺ imaging of hippocampal slices from transgenic mice (IP₃R2^?/? and IP₃R2^?/?;3^?/?). This approach revealed that underneath IP₃R2‐mediated global Ca²⁺ events are an overlooked class of IP₃R‐mediated local events, occurring in astroglial processes. Notably, multiple IP₃Rs were recruited by high frequency stimulation of the Schaffer collaterals, a classical LTP induction protocol. Together, these findings show the dependence of LTP and gliotransmission on Ca²⁺ release by astrocytic IP₃Rs. GLIA 2017;65:502–513     

Endoluminal MR imaging of porcine gastric structure in vivo

Background and aims

Recently, several new endoscopic instruments have been developed. However, even with the full use of current modalities, the safety of endoscopic surgery is not guaranteed. Information regarding factors such as fibrosis and the blood vessels under the mucosa is very important for avoiding procedure-related complications. The aim of this study was to define the detailed anatomy of the gastric wall structure in vivo using original endoluminal radiofrequency coils for safer endoscopic therapy.

Methods

Swine were used as the subjects and controlled with general anesthesia. Anatomical images were obtained with T1-weighted fast spin echo (T1FSE) and T2-weighted fast spin echo (T2FSE). Dynamic magnetic resonance (MR) angiography was also obtained with three-dimensional T1-weighted fast spoiled gradient recalled acquisition in the steady state (3D-DMRA) following the injection of hyaluronic acid sodium into the submucosal layer.

Results

Porcine gastric wall structure was visualized, and four layers were discriminated in the T1FSE and T2FSE images. The vascular structure was clearly recognized in the submucosa on 3D-DMRA.

Conclusion

Endoluminal MR imaging was able to visualize the porcine stomach with similar quality to endoscopic ultrasonography imaging. Additionally, it was possible to visualize the vascular structures in the submucosal layer. This is the first report to show that blood vessels under the gastric mucosa can be depicted in vivo.     

Determination of medullasin levels for the diagnosis of multiple sclerosis

Medullasin levels in granulocytes of patients with neurological diseases and healthy volunteers were determined by the enzyme immunoassay using mouse monoclonal antibodies against human medullasin and o-phenylenediamine-H2O2 as the detection system of the enzyme activity. One hundred twenty-one out of 159 patients with multiple sclerosis (76.1%) showed positive results (above means of normals + 2SD) in this test, while only 16.9% (24/142) of patients with non-inflammatory neurological diseases had positive results. This enzyme immunoassay method for medullasin is considered to be an useful paraclinical test for the diagnosis of multiple sclerosis.     

Genetic contribution of tumor necrosis factor (TNF)-alpha gene promoter (-1031, -863 and -857) and TNF receptor 2 gene polymorphisms in endometriosis susceptibility

PROBLEM: Tumor necrosis factor (TNF)-alpha is a major cytokine involved in inflammatory and immune function. The aim of this study was to investigate whether polymorphisms at positions -1031, -863 and -857 in the TNF gene promoter region (TNFA) and TNF receptor type 2 gene (TNFR2) are responsible in part for genetic susceptibility to endometriosis. METHODS OF STUDY: TNFA and TNFR2 polymorphisms were determined in 123 patients with endometriosis and 165 fertile healthy women by the polymerase chain reaction (PCR) - preferential homoduplex formation assay and PCR-restriction fragment length polymorphism, respectively. RESULTS: The frequency of the TNFA-U01 haplotype was increased significantly in patients with endometriosis compared with controls (P = 0.045, OR = 1.45). The TNFA-U01 haplotype was strongly associated with HLA-B*0702. No difference was found in TNFR2 polymorphism between patients and controls. CONCLUSION: Our results indicated that TNFA promoter polymorphism was associated with susceptibility to endometriosis. However, this association was not independent of HLA-class I polymorphisms.     

七叶树皂苷和熊果酸类化合物对HIV—1蛋白酶活性抑制作用的初步研究*

目的:探讨七叶树皂苷和熊果酸及其衍生物对HIV-1蛋白酶活性的抑制作用,探讨构效关系。方法:采用体外实验法,将待测化合物、HIV-1蛋白酶基质与HIV-1蛋白酶在37℃共温育,根据HIV-1蛋白酶对其基质的水解强度计算待测化合物对HIV-1蛋白酶活性的抑制作用。结果:七叶树总皂苷、七叶树皂苷-Ia和七叶树皂苷-Ib混合物、异七叶树皂苷-Ia和异七叶树皂苷-Ib混合物、七叶树皂苷-Ia、全乙酰化七叶树皂苷-Ia、七叶树皂苷-Ib、熊果酸和乙酰熊果酸在100μmol.L-1浓度对HIV-1蛋白酶活性的抑制率分别为86%,89.9%,50.8%,100%,74.6%,89.3%,100%和100%。七叶树皂苷-Ia、全乙酰化七叶树皂苷-Ia、七叶树皂苷-Ib、熊果酸和乙酰熊果酸对HIV-1蛋白酶活性抑制作用的IC50分别为35,35,50,8和13μmol.L-1。阳性对照药乙酰胃酶抑素在本实验条件下的IC50为0.30μmo.lL-1。在100μmol.L-1浓度,七叶树皂苷-IVc,-IVd,-IVe,-IVf,异七叶树皂苷-Ia,-Ib,-IIa,-IIb,原七叶树皂苷元,21β-O-巴豆酰基原七叶树皂苷元,21β-O-当归酰基原七叶树皂苷元,2α-羟基熊果酸和委陵菜酸对HIV-1蛋白酶活性的抑制率<50%。结论:七叶树总皂苷、七叶树皂苷-Ia和七叶树皂苷-Ib混合物、异七叶树皂苷-Ia和异七叶树皂苷-Ib混合物、七叶树皂苷-Ia、全乙酰化七叶树皂苷-Ia、七叶树皂苷-Ib、熊果酸和乙酰熊果酸对HIV-1蛋白酶活性有抑制作用,最强者为七叶树皂苷-Ia、熊果酸和乙酰熊果酸。     

Human prostate cancer cell death by novel anticancer compounds, apoptosis-inducing nucleosides from CD57+ HLA-DR(bright) natural suppressor cell line

BACKGROUND: We validated the induction of apoptosis in human prostate cancer PC3 cells by apoptosis-inducing nucleosides (AINs) released from the CD57(+)HLA-DR(bright)-natural suppressor (57.DR-NS) cell line. We analyzed the molecular signaling pathway during AINs-induced apoptosis in PC3 cells. METHODS: Direct and indirect co-cultures between 57.DR-NS and PC3 cells were performed. AINs were isolated by high-performance liquid chromatography (HPLC) from 57.DR-NS cell cultures. Apoptosis in PC3 cells was analyzed by DNA fragmentation, sub-G(1) DNA content with flow cytometry, and terminal deoxynucleotide transferase-mediated dUTP nick end-labeling (TUNEL) method. The DNA strand breaks and activation of caspase-3 in PC3 cells were measured by DNA unwinding and flow cytometry assay. RESULTS: The 57.DR-NS cell line generated apoptosis in PC3 cells via AINs. AINs isolated from 57.DR-NS cell cultures induced apoptosis in PC3 cells. Furthermore, we found DNA strand breaks followed by activation of caspase-3 during AINs-induced apoptosis in PC3 cells. CONCLUSIONS: The data obtained here indicated that AINs could induce apoptosis in PC3 cells through DNA strand breaks and activation of caspase-3.     

Dose-response relationship between total cadmium intake calculated from the cadmium concentration in rice collected from each household of farmers and renal dysfunction in inhabitants of the Jinzu River basin,Japan

The association between total cadmium (Cd) intake and abnormal urinary findings was investigated in the Cd-polluted Jinzu River basin. In 1967 and 1968 the most systematic and large-scale health examinations were conducted among the entire population aged over 30 years of this region. We performed this study by targeting the subjects participating in the 1967 health survey conducted mainly in the heavily polluted area. From subjects who had eaten household rice of known Cd concentration, 1,075 inhabitants who had either resided in their current household since birth or who had moved there from a non-polluted area (group A), and 780 inhabitants who had resided in the current household since birth (group B), were selected as the target population. The total Cd intake for each person was calculated from the Cd dose ingested from rice and other foods. Logistic regression analysis was performed using the prevalence of abnormal urinary findings (proteinuria, glucosuria and proteinuria with glucosuria) as the criterion variable and the total Cd intake and age as explanatory variables. In subjects of groups A and B the odds ratios became higher as the dose of total Cd intake increased. Odds ratios in subjects of group A were statistically significant except for glucosuria of men and proteinuria of women. In subjects of group B the odds ratios were also significant for proteinuria + glucosuria of men and glucosuria of women. It was demonstrated that the greater the increase in total Cd intake, the greater the increase in abnormal urinary findings in the Jinzu River basin, and the association of the two factors was very close.     

Relationship between cadmium concentration in rice and renal dysfunction in individual subjects of the Jinzu River basin determined using a logistic regression analysis

We investigated the association between the Cd concentration in rice and renal dysfunction in individuals living in the Cd-polluted Jinzu River basin, using a logistic regression analysis. In the cases of logistic regression analysis for people (1) who had either resided in the present hamlet since birth or who had moved there from a non-polluted area and for those (2) who had resided in the present hamlet since birth, except for glucosuria in males, all partial correlation coefficients between the Cd concentration in rice and occurrence of abnormal urinary findings were statistically significant in both sexes. The allowable level of Cd concentration in rice was calculated by substituting the abnormality rates of urinary findings of the controls in the 40-49, 50-59 and 60-69 year age groups into the logistic regression formula for people (3). The value for subjects aged 50 years was 0.13 and 0.17 ppm for males and females, respectively, with regard to proteinuria and 0.15 and 0.10 ppm for males and females, respectively, with regard to proteinuria+glucosuria.