Deconvolution as a novel approach to analyze moment-to-moment free fatty acid release

Objective: Recent studies have shown that free fatty acid (FFA) release is pulsatile and that this pattern is controlled by the sympathetic nervous system. It is, then, necessary to understand and characterize adipose tissue lipolysis to elucidate its effect on metabolism. In this study, we introduce deconvolution as a method to detect and quantify pulsatile FFA release. Research Methods and Procedures: Octanoate, a medium‐chain fatty acid, was infused in male mongrel dogs (n = 7) to mimic the pulsatile appearance of plasma FFAs. Deconvolution analysis was used to reconstruct the number and timing of infused octanoate pulses from plasma FFA concentrations. Results: Deconvolution analysis was able to reconstruct the exogenously infused pulses of octanoate used to mimic pulsatile appearance of FFAs (pulse frequency, 8 per hour; interpulse interval, 7 minutes). However, determination of pulse mass was less accurate (1.0 ± 0.0 vs. 0.54 ± 0.1 mM). The addition of varying levels of Gaussian noise to non‐oscillatory FFA time series did not lead to detection of extraneous FFA pulses. However, goodness of fit declined with increasing variability. Discussion: These results support the use of deconvolution as an accurate approach to determine the temporal sequence of endogenous FFA release.     

The indispensable role of CCR5 for in vivo suppressor function of tumor-derived CD103+ effector/memory regulatory T cells

CD103 is a marker for identification of effector/memory regulatory T cells (Tregs). CD103(+) Tregs are potent suppressors of tissue inflammation in several infectious diseases, autoimmune diseases, and cancers. However, the underlying mechanisms for this potent suppression ability remain unclear. The current study was designed to clarify this issue. Unexpectedly, we found both CD103(+) and CD103(-) Tregs had similar suppression capacity in vitro. We then chose a murine tumor model for investigation of the in vivo behavior of these Tregs. The suppression ability in vivo against the anti-tumor ability of CD8(+) T cells was restricted to CD103(+) Tregs although both Tregs had equal in vitro suppression ability. In addition, CD103(+) Tregs expressed significantly higher levels of CCR5 than those of CD103(-) Tregs and accumulated more in tumors than did CD103(-) Tregs. Furthermore, blockade of CCR5 signaling, either by CCR5(-/-)CD103(+) Tregs or by CCL5 knockdown tumor, could reduce the migration of CD103(+) Tregs into tumors and impair their in vivo suppression ability. In conclusion, these results indicate that the potent in vivo suppression ability of CD103(+) Tregs is due to the tissue-migration ability through CCR5 expression.     

Targeted elimination of peroxisome proliferator-activated receptor gamma in beta cells leads to abnormalities in islet mass without compromising glucose homeostasis

The nuclear hormone receptor peroxisome proliferator-activated receptor gamma (PPAR gamma) is an important regulator of lipid and glucose homeostasis and cellular differentiation. Studies of many cell types in vitro and in vivo have demonstrated that activation of PPAR gamma can reduce cellular proliferation. We show here that activation of PPAR gamma is sufficient to reduce the proliferation of cultured insulinoma cell lines. We created a model with mice in which the expression of the PPARG gene in beta cells was eliminated (beta gamma KO mice), and these mice were found to have significant islet hyperplasia on a chow diet. Interestingly, the normal expansion of beta-cell mass that occurs in control mice in response to high-fat feeding is markedly blunted in these animals. Despite this alteration in beta-cell mass, no effect on glucose homeostasis in beta gamma KO mice was noted. Additionally, while thiazolidinediones enhanced insulin secretion from cultured wild-type islets, administration of rosiglitazone to insulin-resistant control and beta gamma KO mice revealed that PPAR gamma in beta cells is not required for the antidiabetic actions of these compounds. These data demonstrate a critical physiological role for PPAR gamma function in beta-cell proliferation and also indicate that the mechanisms controlling beta-cell hyperplasia in obesity are different from those that regulate baseline cell mass in the islet.     

Indication of dynamic neurovascular coupling from inconsistency between EEG and fMRI indices across sleep–wake states

Sleep and Biological Rhythms - Neurovascular coupling (NVC), the transient regional hyperemia following the evoked neuronal responses, is the basis of blood oxygenation level-dependent techniques...     

Production and characterization of a monoclonal antibody that binds Reed-Sternberg cells

A murine monoclonal antibody, termed HeFi-1, was produced after immunization with the L428 Hodgkin's disease tissue culture cell line. HeFi-1 selectively stained only the Reed-Sternberg or Hodgkin's cells in 18 of 18 cases of Hodgkin's disease, including the nodular sclerosis, mixed cellularity, and lymphocyte-depleted histologic subtypes. HeFi-1 did not stain any cells in normal lung, brain, salivary gland, thyroid, gall bladder, pancreas, liver, testis, breast, endometrium, or kidney. Rare large cells at the edge of the lymphoid follicles were stained in normal tonsil, colon, and hyperplastic thymus. There was no staining of any cells in 14 cases of B cell non-Hodgkin's lymphoma; however, the malignant cells in three of 11 cases of non-Hodgkin's lymphoma which appeared to express T cell markers were also stained with HeFi-1. Tissue culture cell lines including the T cell acute lymphocytic leukemia lines MOLT4 and CEM, the histiocytic cell line U-937, and the amniotic cell line WISH were not stained. Seven Epstein Barr virus (EBV)-positive lymphoblastoid cell lines were stained with HeFi-1, but there was no staining of three EBV+ African Burkitt's lymphoma cell lines or three EBV- American Burkitt's cell lines. HeFi-1 did not block the ability of the L428 cells to stimulate a mixed lymphocyte reaction or function as accessory cells for mitogen-induced human T cell proliferative responses. Modulation of the HeFi-1 cell surface antigen on the L428 cells was not observed. HeFi-1 specifically immunoprecipitated a cell surface protein of approximately 120,000 daltons from both the L428 and EBV+ lymphoblastoid cell lines. HeFi-1 monoclonal antibody should prove useful not only in the diagnosis, staging, and potential therapy of Hodgkin's disease, but also for determining the cell of origin of the Reed-Sternberg cell.     

Progression of Kidney Disease in Non-Diabetic Patients with Coronary Artery Disease: Predictive Role of Circulating Matrix Metalloproteinase-2, -3, and -9

Background

Circulating matrix metalloproteinase (MMP)-2, -3 and -9 are well recognized in predicting cardiovascular outcome in coronary artery disease (CAD), but their risks for chronic kidney disease (CKD) are lacking. Therefore, the present study aimed to investigate whether circulating MMP levels could independently predict future kidney disease progression in non-diabetic CAD patients.

Methods

The prospective study enrolled 251 non-diabetic subjects referred for coronary angiography, containing normal coronary artery (n = 30) and CAD with insignificant (n = 95) and significant (n = 126) stenosis. Estimated glomerular filtration rate (eGFR) was calculated using the CKD-EPI formula. eGFR decline rate was calculated and the primary endpoint was a decline in eGFR over 25% from baseline.

Results

The eGFR decline rate (ml/min/1.73 m² per year) in patients with CAD (1.22 [−1.27, 1.05]) was greater than that in those with normal coronary artery (0.21 [−2.63, 0.47], P<0.01). The circulating MMP-2, -3 and -9 were independently associated with faster eGFR decline among CAD patients. The mean follow-up period was 8.5±2.4 years, and 39 patients reached the primary endpoint. In multivariate Cox regression model, the adjusted hazard ratios of MMP-2 ≥861 ng/mL, MMP-3 ≥227 ng/mL and MMP-9 ≥49 ng/mL for predicting CKD progression were 2.47 (95% CI, 1.21 to 5.07), 2.15 (1.12 to 4.18), and 4.71 (2.14 to 10.4), respectively. While added to a model of conventional risk factors and baseline eGFR, MMP-2, -3 and -9 further significantly improved the model predictability for CKD progression (c statistic, 0.817). In the sensitivity analyses, the results were similar no matter if we changed the endpoints of a decline of >20% in eGFR from baseline or final eGFR < 60 mL/min/1.73 m².

Conclusion

Circulating MMP-2, -3 and -9 are independently associated with kidney disease progression in non-diabetic CAD patients and add incremental predictive power to conventional risk factors.     

Blockade of lordosis by androst-1,4,6-triene-3,17-dione (ATD) and tamoxifen in female hamsters primed with testosterone propionate

Normal female hamsters display lordosis after testosterone propionate (TP) plus progesterone (P) treatments. Such effect is probably mediated through aromatization of testosterone (T) into estradiol. If so, then an aromatase inhibitor (ATD) or an estrogen antagonist (tamoxifen, TAM) should be able to block the activational effect of T on lordosis. To test this hypothesis, 48 ovariectomized female hamsters were assigned into six groups which, according to treatments received, were ATD + TP, TAM + TP, OIL + TP, ATD + EB (estradiol benzoate), TAM + EB, and OIL + EB groups. The groups received assigned treatments for 2 days and were injected with P on the third day. Five minutes of behavior test was conducted 4 hr after P injection. The OIL + TP, OIL + EB, and ATD + EB groups all had averaged total lordosis duration (TLD) longer than 200 sec. The TLD of the TAM + EB group was only 117 sec. The ATD + TP and TAM + TP groups showed almost no lordosis. The results showed that the estrogen antagonist (TAM) impaired lordosis no matter whether the animals were primed with TP or EB, but the aromatase inhibitor (ATD) blocked lordosis only in TP primed females. It is concluded that the aromatization of T to estrogen is required for testosterone activation of lordosis in female hamsters.     

Effects of Cystamine on antioxidant activities and regulatory T cells in lupus‐prone mice

Attenuated antioxidant activities, irregular cytokines expressions and reduced regulatory T cells, are strongly associated with the pathogenesis of systemic lupus erythematosus (SLE). Despite the well‐established beneficial effects of cystamine on lupus‐prone mice, the extent to which cystamine contributes to antioxidant activity and the reduction of regulatory T cells has seldom been investigated. Therefore, this study elucidates how cystamine affects anti‐oxidant activities in NZB/W F1 mice by performing assays of Glutathione (GSH), 1,1‐diphenyl‐2‐ picryl‐hydrazyl (DPPH) and malondialdehyde thiobarbituric acid (MDA). In addition, investigations of the effects of cystamine on CD4⁺/CD25⁺ regulatory T cells and interleukin‐6 (IL6)/STAT‐3 signalling were performed with flow cytometry and immunoblots. Experimental results reveal more significantly reduced MDA and increased GSH and DPPH in NZB/W F1 mice receiving cystamine than in those mice receiving PBS. Meanwhile, CD4⁺/CD25⁺ regulatory T cells more significantly increase in NZB/W F1 mice receiving cystamine than in those mice receiving PBS, accompanied by significantly reduced IL‐6/phosphorylated STAT‐3 expression. The above findings suggest the beneficial effects of cystamine in terms of increasing antioxidant activities and CD4⁺/CD25⁺ regulatory T cells in lupus‐prone mice by suppressing IL‐6/STAT3 signalling.