TMBIM1 is an inhibitor of adipogenesis and its depletion promotes adipocyte hyperplasia and improves obesity-related metabolic disease

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The size of a melanin-based plumage ornament correlates with glucocorticoid receptor concentrations in the skin of that ornament

Glucocorticoid hormones such as corticosterone (CORT) play crucial roles in many physiological processes. CORT''s actions are primarily mediated via binding to two receptors (glucocorticoid receptors (GRs) and mineralocorticoid receptors (MRs)) in different target tissues. CORT receptors can be independently regulated from circulating hormone titres, from tissue to tissue and even within different regions of the same tissue type. Increasing evidence has shown relationships between circulating CORT and melanin-based pigmentation in skin and feathers, yet to our knowledge, there have been no studies of CORT receptors in the skin of melanized ornaments. Male house sparrows (Passer domesticus) have a black, melanized bib, and evidence suggests that bib size is an important intraspecific signal. We examined the relationship between bib area and tissue sensitivity to CORT by quantifying GR and MR in bib skin and in adjacent paler-feathered belly skin (as a control tissue) at different life-history stages using radioligand binding assays. Males with larger bibs relative to their life-history stage had less GR in bib skin, but not belly skin, than males with smaller bibs. These results suggest a connection between the size of a melanin-based ornament and the underlying tissue''s responsiveness to CORT.     

Quantification of hair cortisol concentration in common marmosets (Callithrix jacchus) and tufted capuchins (Cebus apella)

Quantifying cortisol concentration in hair is a non‐invasive biomarker of long‐term hypothalamic‐pituitary‐adrenal (HPA) activation, and thus can provide important information on laboratory animal health. Marmosets (Callithrix jacchus) and capuchins (Cebus apella) are New World primates increasingly used in biomedical and neuroscience research, yet published hair cortisol concentrations for these species are limited. Review of the existing published hair cortisol values from marmosets reveals highly discrepant values and the use of variable techniques for hair collection, processing, and cortisol extraction. In this investigation we utilized a well‐established, standardized protocol to extract and quantify cortisol from marmoset (n = 12) and capuchin (n = 4) hair. Shaved hair samples were collected from the upper thigh during scheduled exams and analyzed via methanol extraction and enzyme immunoassay. In marmosets, hair cortisol concentration ranged from 2,710 to 6,267 pg/mg and averaged 4,070 ± 304 pg/mg. In capuchins, hair cortisol concentration ranged from 621 to 2,089 pg/mg and averaged 1,092 ± 338 pg/mg. Hair cortisol concentration was significantly different between marmosets and capuchins, with marmosets having higher concentrations than capuchins. The incorporation of hair cortisol analysis into research protocols provides a non‐invasive measure of HPA axis activity over time, which offers insight into animal health. Utilization of standard protocols across laboratories is essential to obtaining valid measurements and allowing for valuable future cross‐species comparisons.     

Peptide E and other proenkephalin-derived peptides are potent kappa opiate receptor agonists

Various proenkephalin-derived peptides such as peptide E and the bovine adrenal medulla peptides BAM-12P and BAM-22P are potent competitors on mu and kappa binding sites in guinea pig brain sections. Moreover, they are all potent agonists in the rabbit vas deferens, a specific kappa opiate receptor bioassay. As described before, dynorphin and some of its fragments are also potent kappa agonists. Our results suggest that not only prodynorphin-derived peptides could act as endogenous kappa ligands but also some proenkephalin-derived peptides such as peptide E.     

Arachidonic Acid Activates Cation Channels in Bovine Adrenal Chromaffin Cells

Abstract— Microscopic fluorescence analysis of fura-2-loaded bovine adrenal chromaffin cells demonstrates that ～70% of the cells responded to arachidonic acid in increasing the intracellular Ca²⁺ concentration. Because this increase was markedly less in the absence of external Ca²⁺, we examined the effect of arachidonic acid on Ca²⁺ influx electrophysiologically. Bath application of 10 μM arachidonic acid induced a long-lasting inward current when the cell was clamped at -50 mV. Other fatty acids, such as oleic acid, linoleic acid, eicosatrienoic acid, and eicosa-pentaenoic acid, were all ineffective. The current-voltage relationships suggest that arachidonic acid may activate voltage-insensitive channels. Arachidonic acid (2μM) activated a single-channel current in the inside-out patch, even in the presence of inhibitors of cyclooxygenase and lipoxygenase, possibly suggesting that arachidonic acid could activate channels directly. The onset delay of the inward channel current in the outside-out patch configuration (54.02 ± 63.5 s; mean SD) was significantly shorter than that in the inside-out patch one (197.3 ± 177.7 s). Washout of arachidonic acid decreased the probability of channel openings in the outside-out patch but not in the inside-out one. These results suggest that arachidonic acid activates channels reversibly from outside of the plasma membrane. The unitary conductarce for Ca²⁺ of arachidonic acid-activated channel was ～17 pS. The arachidonic acid-activated channel was permeable to Ba²⁺, Ca²⁺, and Na⁺ but not to Cl^?. The opening probability of the arachidonic acid-activated channel did not depend on membrane potential. These results demonstrate that arachidonic acid activates cation-selective, Ca²⁺-permeable channels in bovine adrenal chromaffin cells.     

谷丙甘氨酸胶囊治疗前列腺增生32例临床疗效观察

目的 :观察治疗前列腺疾病药物谷丙甘氨酸胶囊 (安尿通胶囊 )的临床疗效。方法 :32例前列腺增生患者 ,口服谷丙甘氨酸胶囊 ,每次 82 0mg ,tid ,一个疗程后观察排尿症状进行疗效判定。结果 :32例患者经谷丙甘氨酸胶囊治疗一个疗程后 ,显效 9例 ,有效 14例 ,无效 9例 ,总有效率 72 %。 32例患者用药期间均未发生不良反应。结论 :谷丙甘氨酸胶囊是安全有效的治疗前列腺增生的药物。     

Utility of Epinephrine Levels in Determining Adrenal Vein Cannulation During Adrenal Venous Sampling for Primary Aldosteronism

ObjectiveIn patients with primary aldosteronism, adrenal venous sampling (AVS) is performed to determine the presence of unilateral or bilateral adrenal disease. During AVS, verification of catheter positioning within the left adrenal vein (AV) and the right AV by comparison of AV and inferior vena cava (IVC) cortisol levels can be variable. The objective of this study was to determine the utility of AV epinephrine levels in assessing successful AV cannulation.MethodsThis was a single institution, retrospective review of patients who underwent AVS with cosyntropin stimulation for primary aldosteronism between 2009 and 2018. Successful cannulation of the AV was defined by an AV/IVC cortisol ratio selectivity index (SI) ≥3:1. Epinephrine thresholds to predict catheter placement in the AV were determined using logistic regression. The calculated epinephrine thresholds were compared with previously published thresholds.ResultsAVS was performed on 101 consecutive patients and, based on the SI, successful cannulation of the left AV and right AV occurred in 98 (97%) and 91(90%) patients, respectively. The calculated optimal epinephrine threshold to predict AV cannulation was 364 pg/mL (sensitivity, 92.1%; specificity, 94.6%) and the calculated optimal AV/IVC epinephrine ratio threshold was 27.4, (sensitivity, 92.1%; specificity, 91.3%). Among the 14 patients with failed AV cannulation, 3 patients would have been considered to have successful AVS using AV epinephrine levels >364 pg/mL and AV/IVC epinephrine ratio >27.4 thresholds.ConclusionObtaining 2 right AV samples routinely as well as AV and IVC epinephrine levels during AVS could prevent unnecessary repeat AVS in patients with failed AV cannulation based on cortisol-based SI <3:1.