HLA analysis of immune checkpoint inhibitor-induced and idiopathic isolated ACTH deficiency.

PURPOSE: Isolated adrenocorticotropic hormone deficiency is a rare disease; however, since immune check point inhibitors (ICIs) have become widely used, many more cases have been reported. In this study, we compared the human leukocyte antigen (HLA) signatures between ICI-induced isolated adrenocorticotropic hormone deficiency (IAD) and idiopathic IAD (IIAD). DESIGN AND METHODS: Clinical features and HLA frequencies were compared among 13 patients with ICI-induced IAD, 8 patients with IIAD, and healthy controls. HLA frequencies of healthy controls were adopted from a HLA database of Japanese population. RESULTS: Age and body mass index were higher, while the rate of weight loss was lower, in patients with ICI-induced IAD than in those with IIAD. No HLA alleles had a significantly higher frequency in patients with ICI-induced IAD than in healthy controls, whereas the frequencies of HLA-DRB1*09:01, HLA-DQA1*03:02, and DQB1*03:03 were significantly higher in patients with IIAD than in healthy controls. CONCLUSIONS: ICI-induced IAD and IIAD were different in terms of HLA frequencies. There were no specific HLAs related to ICI-induced IAD, whereas several HLAs in strong linkage disequilibrium were associated with IIAD. This might suggest that the two diseases have different pathological mechanisms. HLAs unique to IIAD may be helpful in predicting its pathophysiology.

Epigenetic regulation of beige adipocyte fate by histone methylation.

Adipose tissue harbors plasticity to adapt to environmental thermal changes. While brown adipocyte is a thermogenic cell which produces heat acutely in response to cold stimuli, beige (or brite) adipocyte is an inducible form of thermogenic adipocytes which emerges in the white adipose depots in response to chronic cold exposure. Such adaptability of adipocytes is regulated by epigenetic mechanisms. Among them, histone methylation is chemically stable and thus is an appropriate epigenetic mark for mediating cellular memory to induce and maintain the beige adipocyte characteristics. The enzymes that catalyze the methylation or demethylation of H3K27 and H3K9 regulate brown adipocyte biogenesis through their catalytic activity-dependent and -independent mechanisms. Resolving the bivalency of H3K4me3 and H3K27me3 as well as "opening" the chromatin structure by demethylation of H3K9 both mediate beige adipogenesis. In addition, it is recently reported that maintenance of beige adipocyte, beige-to-white transition, and cellular memory of prior cold exposure in beige adipocyte are also regulated by histone methylation. A further understanding of the epigenetic mechanism of beige adipocyte biogenesis would unravel the mechanism of the cellular memory of environmental stimuli and provide a novel therapeutics for the metabolic disorders such as obesity and diabetes that are influenced by environmental factors.

Frequency of Achilles Tendon Xanthoma in Patients with Acute Coronary Syndrome.

AIM: We studied the frequency of Achilles tendon xanthoma (ATX) in patients with acute coronary syndrome (ACS). Furthermore, we investigated the differences in clinical findings between ACS patients with and without ATX. METHODS: Patients with ACS (n=335) were admitted to the coronary care unit of Nippon Medical School between July 2011 and December 2014. Informed consent for the measurement of Achilles tendon thickness (ATT) on a radiograph was obtained from 228 patients without tendon rupture. ATT of each side was measured on the radiograph in patients with ACS and in those with acromegaly (n=18), non-familial hypercholesterolemia (non-FH; n=96), and familial hypercholesterolemia (FH; n=31). RESULTS: ATT of the right and left side in ACS patients were 6.9±1.3 and 7.0±1.6 (mm; mean± SD). In acromegaly, non-FH, and FH patients, ATT of the right/left side were 6.6±1.1/6.7±1.1, 6.2±0.9/6.6±1.0, and 9.4±3.3/10.0±3.1, respectively. ATX (ATT ≥9 mm) was found in 26 (11.4%) patients with ACS. Patients with acromegaly and non-FH had no ATX, whereas all patients with FH had ATX. No differences in age and serum lipid profiles were observed between ACS patients with and without ATX. The levels of body mass index and glycated hemoglobin of ACS patients with ATX were significantly greater than those in ACS patients without ATX (26.8±4.0 vs. 23.9±3.3, p＜0.05, and 6.9±1.4% 6.3±1.3%, p＜0.05, respectively). CONCLUSION: This is the first report in which the frequency of ACS patients with ATX was 11.4%. The serum lipid profiles of ACS patients with ATX were similar to those without ATX. In the future, ACS patients with ATX will be diagnosed as having FH.

Regioselective formation of multiple disulfide bonds with the aid of postsynthetic S-tritylation.

Disulfide bond formation performed in solution with the tert-butylthio (StBu) group was accomplished using a free peptide having only the sulfhydryl groups of Cys protected with the aid of postsynthetic S-tritylation. This facilitated removal of the StBu group with subsequent disulfide formation without any difficulty. This strategy using the StBu group in combination with the widely used acetamidomethyl (Acm), 4-methylbenzyl/4-methoxybenzyl (Meb/Mob), and trityl (Trt) groups enables reliable and regioselective synthesis of multicystine peptides.

Identification of the recognition sequence and target proteins for DJ-1 protease.

DJ-1, the product of familial Parkinson's disease gene and an oncogene, is a cysteine protease which plays a role in anti-oxidative stress reaction. In this study, we identified the recognition sequence for DJ-1 protease by using recombinant DJ-1 and a peptide library. Protease activity of DJ-1 lacking C-terminal α-helix (DJ-1ΔH9) was stronger than that of full-sized DJ-1, and the most susceptible sequence digested by DJ-1ΔH9 was valine-lysine-valine-alanine (VKVA) under the optimal conditions of pH 5.5 and 0 mM NaCl. Divalent ions, especially Cu²âº, were inhibitory to DJ-1's protease activity. c-abl oncogene 1 product (ABL1) and kinesin family member 1B (KIF1B) containing VKVA were digested by DJ-1ΔH9.

Dynamic change of chromatin conformation in response to hypoxia enhances the expression of GLUT3 (SLC2A3) by cooperative interaction of hypoxia-inducible factor 1 and KDM3A.

Hypoxia-inducible factor 1 (HIF1) is a master regulator of adaptive gene expression under hypoxia. However, a role for HIF1 in the epigenetic regulation remains unknown. Genome-wide analysis of HIF1 binding sites (chromatin immunoprecipitation [ChIP] with deep sequencing) of endothelial cells clarified that HIF1 mainly binds to the intergenic regions distal from transcriptional starting sites under both normoxia and hypoxia. Next, we examined the temporal profile of gene expression under hypoxic conditions by using DNA microarrays. We clarified that early hypoxia-responsive genes are functionally associated with glycolysis, including GLUT3 (SLC2A3). Acetylated lysine 27 of histone 3 covered the HIF1 binding sites, and HIF1 functioned as an enhancer of SLC2A3 by interaction with lysine (K)-specific demethylase 3A (KDM3A). Knockdown of HIF1α and KDM3A showed that glycolytic genes are regulated by both HIF1 and KDM3A and respond to hypoxia in a manner independent of cell type specificity. We elucidated that both the chromatin conformational structure and histone modification change under hypoxic conditions and enhance the expression of SLC2A3 based on the combined results of chromatin conformation capture (3C) and ChIP assays. KDM3A is recruited to the SLC2A3 locus in an HIF1-dependent manner and demethylates H3K9me2 so as to upregulate its expression. These findings provide novel insights into the interaction between HIF1 and KDM3A and also the epigenetic regulation of HIF1.

Selective breeding of mice for different susceptibilities to high fat diet-induced glucose intolerance: Development of two novel mouse lines, Selectively bred Diet-induced Glucose intolerance-Prone and -Resistant.

UNLABELLED: Aims/Introduction: The development of type 2 diabetes is primarily due to lifestyle and environmental factors, as well as genetics, as shown by familial clustering. To establish mouse lines for evaluating heritable factors determining susceptibility to diet-induced diabetes, we performed selective breeding for differences in high fat diet (HFD)-induced glucose intolerance. MATERIALS AND METHODS: Selective breeding was performed using hybrid mice of C57BL/6J, C3H/HeJ and AKR/N backgrounds. After 5-week HFD feeding, mice showing high and low 2-h blood glucose levels in an oral glucose tolerance test (OGTT) were selected and bred over 14 generations to produce lines prone and resistant to diet-induced glucose intolerance (designated Selectively bred Diet-induced Glucose intolerance-Prone [SDG-P] and -Resistant [SDG-R]). RESULTS: At 5 weeks of age (pre HFD feeding), SDG-P mice showed higher blood glucose levels both in the OGTT and insulin tolerance test as compared to SDG-R mice. After receiving HFD, the glucose intolerance of SDG-P mice became more evident without hyper insulin secretion. In addition, SDG-P mice had greater body weight gain and lower HDL-cholesterol levels as compared to SDG-R mice. In comparison with C57BL/6J, a well-known strain prone to HFD-induced glucose intolerance, SDG-P mice showed significantly higher glucose levels in OGTT after the 5-week HFD feeding. CONCLUSIONS: Susceptibility to HFD-induced glucose intolerance was transmitted over generations and was intensified by selective breeding. The newly established mouse lines, SDG-P and SDG-R, may be useful in investigating the pathophysiology of type 2 diabetes through elucidating the crucial factors for determining the susceptibility to HFD-induced glucose intolerance. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00175.x, 2011).

Practical dietary calorie management, body weight control and energy expenditure of diabetic patients in short-term hospitalization.

AIM: We investigated how dietary management affected body weight (BW) reduction and energy expenditure in obese and normal-weight type 2 diabetic patients. METHODS: Type 2 diabetic patients who were hospitalized for diabetic control (93 men and 51 women) were checked for resting energy expenditure (REE). Subjects were divided into the two groups according to body mass index (BMI): obese (BMI > or = 25), and normal-weight (BMI <25). Following the recommendations by JDS, JAS and JASSO, ideal body weight was calculated as [IBW=height (m) x height (m) x 22 (kg/m(2))], and dietary calorie (kcal/day) was determined as 25 kcal/kg IBW. RESULTS: Dietary calorie intake during hospitalization was similar in both groups. REE was greater in obese than in normal-weight patients. The difference between the calorie intake and energy expenditure (Deltacalorie) was -222+/-26 kcal in obese patients and 69+/-27 kcal in normal-weight patients. Obese patients therefore had larger BW decreases than normal-weight patients (-171+/-12 vs. -92+/-11 g/day, p<0.005). In the obese group, a positive correlation was found between the change of BW and Deltacalorie. This correlation remained after adjusting for age, BMI, gender, and respiratory quotient. Serum lipid profiles were significantly improved in both groups. CONCLUSION: These diet instructions showed the appropriate calorie restriction depending on the BMI and induced reasonable BW reduction in both obese and normal-weight subjects. The dietary program recommended by JDS, JAS and JASSO is practically useful for BW control and for improving lipid metabolism in type 2 diabetic patients.

Phosphatidylcholine hydroperoxide-induced THP-1 cell adhesion to intracellular adhesion molecule-1.

The accumulation of phosphatidylcholine hydroperoxide (PCOOH), a primary oxidation product of phosphatidylcholine (PC), in blood plasma and tissues has been observed in various pathological conditions, including atherosclerosis. However, the biological roles of PCOOH in these conditions remain unknown. To estimate the atherogenicity of PCOOH, we evaluated the effect of PCOOH on THP-1 monocytic cell adherence to immobilized vascular endothelial cell adhesion molecules. THP-1 cell adhesion to intracellular adhesion molecule-1 (ICAM-1) was dose-dependently increased by addition of PCOOH. Phosphatidylcholine hydroxide (a hydroxyl analog of PCOOH) also induced THP-1 cell adhesion to ICAM-1, whereas nonoxidized PC, sn-2 truncated PCs, and other hydroperoxide compounds did not affect the adhesion. In the PCOOH-treated cells, obvious protruding F-actin-rich membrane structures were formed, and lymphocyte function-associated antigen-1 (LFA-1) was localized to the protruding structures. Cytochalasin D, an actin polymerization inhibitor, suppressed the PCOOH-induced cell adhesion to ICAM-1 and the membrane protrusions. These results indicate that PCOOH evokes LFA-1-mediated cell adhesion to ICAM-1 via actin cytoskeletal organization, and the mechanism may participate in monocyte adherence to the arterial wall in the initiation of atherosclerosis.

Association of serum apolipoprotein B48 level with the presence of carotid plaque in type 2 diabetes mellitus.

AIMS: The atherogenicity of chylomicron remnants has been discussed. We examined whether serum apoB48 level is associated with the presence of carotid plaque in type 2 diabetic patients. METHOD: Forty type 2 diabetic patients (21 males and 19 females, 52.8+/-11.8 years old; mean+/-S.D.) were divided into two groups by the presence or absence of carotid plaque. The diurnal change of serum apoB48 level was measured by enzyme-linked immunosorbent assay. RESULTS: Fasting serum apoB48 level was higher in the subjects with carotid plaque than those without (6.5+/-3.8vs. 4.1+/-1.9 microg/ml, p=0.01). Age- and gender-adjusted analysis showed that the presence of carotid plaque was associated with fasting apoB48 (OR 1.43; 95% CI, 1.07-2.09, p=0.04) and triglyceride (OR 1.14; 95% CI, 1.02-1.32, p=0.04) levels. In normal LDL-cholesterol (<140 mg/dl) subjects, the presence of carotid plaque was associated with fasting apoB48 level (OR 2.16; 95% CI, 1.22-5.32, p=0.04), but not associated with fasting triglyceride level (OR 1.11; 95% CI, 0.99-1.30, p=0.13). CONCLUSIONS: Serum apoB48 level was strongly associated with the presence of carotid plaque in type 2 diabetic patients.

Oxidized but not acetylated low-density lipoprotein reduces preproinsulin mRNA expression and secretion of insulin from HIT-T15 cells.

We examined the effect of oxidized low-density lipoprotein (oxLDL) on the insulin secretion in the culture of HIT-T15 cell line, an islet beta-cell line derived from a hamster pancreatic tumor. In order to check the uptake of modified LDL by HIT-T15 cells, we prepared DiI-labeled native LDL (nLDL), acetylated LDL (AcLDL), and oxLDL. After the addition of each LDL into the cultures of HIT-T15 cells, fluorescence microscopic study was done. It was suggested that AcLDL and oxLDL were taken up by HIT-T15 cells, as well as nLDL. mRNA expression of the LDL receptor, CD36, and SR-B1 was detected in HIT-T15 by RT-PCR. The medium insulin level was measured in the culture of HIT-T15 cells with each LDL. oxLDL significantly reduced the insulin secretion stimulated by various concentrations of glucose, the intracellular content of insulin, and the expression of preproinsulin mRNA compared to the control cultures without LDL addition. In contrast, nLDL and AcLDL had no effect on the insulin secretion, the intracellular insulin level, or the expression of preproinsulin mRNA. MTT assay findings (reflecting cell numbers) were not different between cultures with and without LDLs. These results indicated that oxLDL disturbed the insulin metabolism of HIT-T15 cells.