Inadequate dietary magnesium intake increases atherosclerotic plaque development in rabbits

Epidemiological studies have shown dietary magnesium (Mg) intake and serum Mg levels to be inversely correlated with the development of atherosclerosis. We hypothesized that low levels of Mg would promote atherosclerotic plaque development in rabbits. New Zealand white rabbits (4 months old, n = 22) were fed an atherogenic diet containing 0.12% (−Mg), 0.27% (control), or 0.43% (+Mg) Mg for 8 weeks. Blood samples were obtained at baseline, 2, 4, 6, and 8 weeks and were assayed for total cholesterol, high-density lipoprotein (HDL), non-HDL, triglycerides (TG), C-reactive protein, serum Mg, and erythrocyte Mg. Aortas from −Mg had significantly more plaque, with an intima thickness 42% greater than control and 36% greater than +Mg. Serum cholesterol levels rose over time, and at 8 weeks, −Mg had the highest and +Mg the lowest total and non-HDL cholesterol and TG levels, although these results did not reach significance. Over time, serum Mg levels increased, and erythrocyte Mg levels decreased. C-reactive protein significantly increased in all groups at 4 and 6 weeks but returned to baseline levels by 8 weeks. This study supports the hypothesis that inadequate intake of Mg results in an increase in atherosclerotic plaque development in rabbits.     

Role of the ventromedial nucleus of the thalamus in motor behaviour—I. Effects of focal injections of drugs

An assortment of drugs was injected into one or both ventromedial nuclei of the thalamus, to see how these influenced stereotypy, locomotion and posture in spontaneously behaving and actively rotating rats. Unilateral intrathalamic muscimol promoted weak ipsiversive circling, while bilateral treatment gave catalepsy. Similar injections of 4-amino-hex-5-enoic acid, which inhibits γ-aminobutyrate metabolism, raised γ-aminobutyrate levels in the ventromedial nuclei more than three-fold yet had none of these behavioural effects. The indirectly acting γ-aminobutyrate agonists flurazepam and cis-1,3-aminocyclohexane car☐ylic acid had little effect on posture and locomotion and, like muscimol and 4-amino-hex-5-enoic acid, elicited only very weak stereotypies. Procaine behaved like the γ-aminobutyrate antagonist bicuculline, provoking vigorous locomotor hyperactivity and teeth chattering if given uni- or bilaterally. Pretreatment of one ventromedial nucleus with muscimol or 4-amino-hex-5-enoic acid, and to a lesser extent flurazepam or cis-1,3-aminocyclohexane car☐ylic acid, gave rise to pronounced ipsilateral asymmetries when combined with a large systemic dose of apomorphine. Contraversive rotations were initiated by unilateral stereotaxic injection of muscimol into the substantia nigra pars reticulata, or with apomorphine from the supersensitive striatum in unilaterally 6-hydroxydopamine lesioned rats. Drug treatments in the ipsilateral ventromedial nucleus showed a similar rank order of potency at inhibiting these circling behaviours, seemingly by reducing apomorphine-induced posture and muscimol-induced hypermotility. The suppression of circling by muscimol in these tests was highlighted by introducing the compound into the ventromedial nucleus at the height of circling activity. Both types of circling stimulus lost the capacity to increase locomotion, but still caused head turning and stereotypy in rats made cataleptic with bilateral ventromedial muscimol. Treating one ventromedial thalamus with muscimol greatly intensified any pre-existing posture directed towards that side, and vice versa.

These data suggest that the ventromedial nucleus is not involved with the expression of stereotyped behaviours, but can profoundly influence posture and locomotion, especially in the presence of some other motor stimulus. The recovery of circus movements in rats with impaired ventromedial nucleus function implies this nucleus is not essential for the execution of circling in these models.     

Nonspecific antiviral immunity by formalin-fixed Coxiella burnetii is enhanced in the absence of nitric oxide

Mice treated with a single injection of formalin-fixed Coxiella burnetii showed a significant increase in resistance to vaccinia virus (VV) infection compared to untreated mice. C. burnetii stimulated dramatically high levels of nitric oxide (NO) in the serum of treated mice, suggesting that NO might play a role in resistance to virus infection. To test this hypothesis, the effect of C. burnetii treatment on VV replication was examined in NOS2-/- and wild-type mice. C. burnetii treatment inhibited VV replication in both the knockout and wild-type mice but the effect was significantly greater in the NOS2-/- mice. Experiments in IFNgamma receptor knockout mice indicated that the nonspecific antiviral immunity induced by C. burnetii was dependent on IFNgamma and not NO. In the absence of NO, indoleamine 2,3-dioxygenase (IDO) was increased in C. burnetii-treated mice and this may contribute to the accelerated virus clearance in NOS2-/- mice.     

Activation of human neutrophils by the pollutant sodium sulfite: effect on cytokine production,chemotaxis, and cell surface expression of cell adhesion molecules

In chronic beryllium disease (CBD), a granulomatous lung disease characterized by hypersensitivity to beryllium salts (BE), BE challenge of bronchoalveolar lavage cells induces IFNgamma. Although nitric oxide (NO) is elevated in CBD airways, the effects of NO on CBD IFNgamma responses are unknown. Here we report that BE-stimulated IFNgamma production in CBD lavage cells was markedly reduced (74%) by the NO generator DETA NONOate. Investigation of IFNgamma-stimulatory cytokine involvement indicated that lavage cell IL-18 was significantly increased (fourfold) by BE and reduced (64%) by DETA NONOate but IL-12 was undetectable. IL-18 production was caspase-1-dependent but caspase 1 inhibition reduced IFNgamma only partially (43%). Specific antibody depletion of lavage cell IL-18 yielded marginal reduction (19%) of IFNgamma. Data are the first to show that: (1) BE stimulates IL-18 as well as IFNgamma in CBD; (2) BE cytokine responses are NO-sensitive; and (3) NO down-regulation of IFNgamma involves other sites in addition to IL-18.     

Human multiple myeloma cells express peroxisome proliferator-activated receptor gamma and undergo apoptosis upon exposure to PPARgamma ligands

Multiple myeloma is essentially an incurable malignancy and it is therefore of great interest to develop new therapeutic approaches. We previously reported that human B cell-lymphomas express the nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma) and are killed by PPARgamma ligands. Herein, we investigate the therapeutic potential of PPARgamma ligands for multiple myeloma. The human multiple myeloma cell lines ANBL6 and 8226 express PPARgamma mRNA and protein. The PPARgamma ligands, 15-deoxy-Delta12,14-prostaglandin J2 (15d-PGJ2) and ciglitazone, induced multiple myeloma cell apoptosis as determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay, loss of mitochondrial membrane potential, and caspase activation. Importantly, the ability of PPARgamma ligands to kill both multiple myeloma cell lines was not abrogated by Interleukin-6 (IL-6), a multiple myeloma growth survival factor. Finally, the RXR ligand 9-cis retinoic acid (9-cis RA) in combination with PPARgamma ligands greatly enhanced multiple myeloma cell killing. These new findings support that PPARgamma ligands may represent a novel therapy for multiple myeloma.     

PPARY2基因Pro12Ala和C1431T多态性及其单倍型与2型糖尿病和肥胖的相关性研究

目的 研究过氧化物体增殖活化受体γ2(peroxisome proliferator activated receptorγ2,PPARγ2)基因Pro12Ala和C1431T多态性及其单倍型与汉族人2型糖尿病、肥胖的关系.方法 应用聚合酶链反应-限制性片段长度多态性的方法,对207例2型糖尿病患者和101名非糖尿病对照者进行PPARγ2基因Pro12Ala和C1431T多态性研究.结果 (1)在非糖尿病对照人群中Aal 12等位基因频率是0.064,T1431等位基因频率是0.252.单倍型分析显示Pro12Ala和C1431T两个位点连锁不平衡(D'=0.63,r2=0.074),组成了3种常见单倍型Pro-C、Pro-T和Ala-T.(2)Pro12Ala和C1431T多态性分布及其单倍型分布频率在2型糖尿病组与对照组组间差异均无统计学意义(P>0.05).(3)Pro12Ala变异与糖尿病患者的血压、血脂相关,地等位基因降低非肥胖糖尿病患者的舒张压(P<0.05),而对肥胖糖尿病患者的血脂水平无保护作用(P<0.05);C1431T多态性与糖尿病患者的超重和肥胖相关,超重和肥胖的糖尿病者T等位基因频率相对较高(P<0.05).结论 Pro12Ala和C1431T多态性可能在汉族人糖尿病发病中不是起主要作用;C1431T多态性与糖尿病患者的超重和肥胖相关.     

Inactivation by 6-hydroxydopamine of the cerebral factor(s) responsible for the inhibition of the autoxidation of norepinephrine in vitro

The effect of extracts from rat cerebral cortex was examined on the stability of norepinephrine-HC1 (NE) in 16 mM Na-phosphate buffer, pH 7.4, at 37 degrees C. The autoxidation products of NE were detected spectrophotometrically at 480 nm. Dialysed samples from a synaptosomal preparation and from the 100,000 g supernatant of a crude homogenate were tested. Aliquots from these preparations, in the range of 0.005-5.0 or 0.01-10.0 micrograms protein/ml, respectively, produced up to 80-85% inhibition of the autoxidation of 100 microM NE for a period of at least 3 h. Similar results were obtained with albumin and ovalbumin at 10- and 10(3)-times higher concentrations, respectively. After the preparations were exposed to 0.1-1.0 mg 6-hydroxydopamine-HC1/mg protein for 5 min at 25 degrees C followed by rapid dialysis, the maximal inhibitory effect was reduced to between 95% to less than 5% of control values. The percent inactivation by a given quantity of 6-hydroxydopamine (6-OHDA) was inversely related to the potency of the untreated sample. Additional observations are presented which suggest that the destruction of the antioxidant activity is caused by breakdown products of 6-OHDA reacting with nucleophilic sites of the preparation. Similar inactivating substances are expected to be formed from other autoxidizing catecholamines, although at a slower rate.     

CD8+T-bet+ cells as a predominant biomarker for inclusion body myositis

Background

Myositis is a heterogeneous group of muscular auto-immune diseases with clinical and pathological criteria that allow the classification of patients into different sub-groups. Inclusion body myositis is the most frequent myositis above fifty years of age. Diagnosing inclusion body myositis requires expertise and is challenging. Little is known concerning the pathogenic mechanisms of this disease in which conventional suppressive-immune therapies are inefficacious.

Increased central adiposity is associated with pro-inflammatory immunoglobulin G N-glycans

Background

Increased body fat may be associated with an increased risk of developing an underlying pro-inflammatory state, thus leading to greater risk of developing certain chronic conditions. Immunoglobulin G has the ability to exert both anti- and pro-inflammatory effects, and the N-glycosylation of the fragment crystallisable portion is involved in mediating this process. Body mass index, a rudimentary yet gold standard indication for body fat, has been shown to be associated with agalactosylated immunoglobulin G N-glycans.

PD-1-Expressing SARS-CoV-2-Specific CD8+ T Cells Are Not Exhausted,but Functional in Patients with COVID-19

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