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.

Insulin and heparin challenge tests are useful for choosing an optimal insulin regimen in a case of subcutaneous insulin resistance

A 38-year-old woman with type 1 diabetes, whose fasting plasma glucose levels were >500 mg/dL under 176 U/day of subcutaneous insulin injection, was admitted to Nippon Medical School Hospital, Tokyo, Japan. When insulin was administered intravenously, she was able to maintain favorable glycemic control even under 24 U/day of regular insulin, showing that she was accompanied by subcutaneous insulin resistance. To choose an optimal insulin regimen, we carried out subcutaneous insulin challenge tests without or with heparin mixture, and found a cocktail of insulin lispro and heparin could reduce blood glucose levels markedly. As a consequence, she achieved favorable blood glucose control by continuous subcutaneous insulin infusion of the cocktail. In summary, the insulin and heparin challenge tests are useful for choosing an optimal insulin regimen in cases of subcutaneous insulin resistance.

SAT-456 Reduced Cholesterol Absorption and Synthesis Markers in Patients with Hyperthyroidism Due to Graves’ Disease

Background:Thyroid hormones have been reported to promote cell-surface expression of low-density lipoprotein receptor (LDL-R), and also increase mRNA expression of HMG-CoA reductase at the same time. Since LDL cholesterol (LDL-C) uptake via LDL-R is relatively superior to cholesterol synthesis in hyperthyroidism, plasma LDL-C levels can be lower as compared to euthyroid state. Conversely, hypothyroidism can increase plasma LDL-C levels because cholesterol absorption via Niemann-Pick C1-like 1 has been suggested to increase in hypothyroidism. However, there have been no reports about changes of cholesterol absorption and synthesis markers by the treatment of hyperthyroidism in patients with Graves’ disease. Patients and method: We collected plasma samples from patients with hyperthyroidism, who were diagnosed as Graves’ disease (n=17, M/F: 4/13, age: 24-70 years old). Thyroid hormones, general lipid profiles (Total cholesterol: TC, LDL-C, high-density lipoprotein cholesterol: HDL-C and triglyceride: TG), apolipoproteins, markers of cholesterol synthesis (lathosterol) and absorption (campesterol, sitosterol, cholestanol), lipoprotein lipase (LPL), and proprotein convertase subtilisin/kexin type 9 (PCSK9) were analyzed before treatment, and at euthyroid state (eu), 3 and 6 months after attaining euthyroid state (eu-3M and eu-6M). Result: It took 159.2±108.6 days to attain euthyroid state by the thiamazole treatment. TC, LDL-C and HDL-C levels were increased at eu (TC, 144.5±26.7 to 225.0±61.6; LDL-C, 77.8±20.9 to 138.9±43.9; HDL-C, 49.7±12.6 to 67.9±20.0 mg/dL: P<0.0001 vs before treatment, respectively). Such changes remained at eu-3M and eu-6M. TG was not changed at eu, but significantly increased at eu-6M (85.0±49.1 to 113.7±60.8 mg/dL, P=0.02). Cholesterol absorption markers were increased at eu, eu-3M and eu-6M (e.g. campesterol, 2.6±1.2 to 4.9±2.3; sitosterol, 1.5±0.6 to 2.9±1.4; cholestanol, 1.9±0.6 to 3.2±1.1 μg/mL: P<0.0001, eu vs before treatment, respectively). Cholesterol synthesis marker was increased at eu, eu-3M and eu-6M (e.g. lathosterol, 1.8±0.7 to 2.3±0.9 μg/mL: P=0.005, eu vs before treatment). Both LPL and PCSK9 were also increased at eu, eu-3M and eu-6M. Conclusion: These data suggest that both cholesterol absorption and synthesis are downregulated in patients with hyperthyroidism due to Graves’ disease and can be restored by attaining euthyroid state. In turn, LDL-C and TG levels should be carefully monitored during the treatment of Graves’ disease because hyperlipidemia could emerge in euthyroid state.

Glucocorticoid induces human beta cell dysfunction by involving riborepressor GAS5 LincRNA

OBJECTIVE

A widely recognized metabolic side effect of glucocorticoid (GC) therapy is steroid-induced diabetes mellitus (DM). However, studies on the molecular basis of GC-induced pancreatic beta cell dysfunction in human beta cells are lacking. The significance of non-coding RNAs in various cellular processes is emerging. In this study, we aimed to show the direct negative impact of GC on beta cell function and elucidate the role of riborepressor GAS5 lincRNA in the GC signaling pathway in human pancreatic beta cells.

METHODS

Patients undergoing two weeks of high-dose prednisolone therapy were monitored for C-peptide levels. Human pancreatic islets and the human beta cell line EndoC-βH1 were incubated in pharmacological concentrations of dexamethasone. The GAS5 level was modulated using anti-sense LNA gapmeR or short oligonucleotides with GAS5 HREM (hormone response element motif). Immunoblotting and/or real-time PCR were used to assess changes in protein and RNA expression, respectively. Functional characterization included glucose-stimulated insulin secretion and apoptosis assays. Correlation analysis was performed on RNAseq data of human pancreatic islets.

RESULTS

We found reduced C-peptide levels in patients undergoing high-dose GC therapy. Human islets and the human beta cell line EndoC-βH1 exposed to GC exhibited reduced insulin secretion and increased apoptosis. Concomitantly, reduced expression of important beta cell transcription factors, PDX1 and NKX6-1, as well as exocytotic protein SYT13 were observed. The expression of the glucocorticoid receptor was decreased, while that of serum and glucocorticoid-regulated kinase 1 (SGK1) was elevated. The expression of these genes was found to significantly correlate with GAS5 in human islet transcriptomics data. Increasing GAS5 levels using GAS5 HREM alleviated the inhibitory effects of dexamethasone on insulin secretion.

CONCLUSIONS

The direct adverse effect of glucocorticoid in human beta cell function is mediated via important beta cell proteins and components of the GC signaling pathway in an intricate interplay with GAS5 lincRNA, a potentially novel therapeutic target to counter GC-mediated beta cell dysfunction.

Metformin Attenuates Early-Stage Atherosclerosis in Mildly Hyperglycemic Oikawa-Nagao Mice

Aim: Although metformin treatment has been reported to reduce the risk of cardiovascular events in patients with type 2 diabetes, the underlying mechanisms have not been elucidated fully. Here we assessed atherosclerotic lesion formation in newly established 2 mouse lines with different blood glucose levels (Oikawa-Nagao Diabetes-Prone [ON-DP] and -Resistant [ON-DR]) to evaluate the effect of metformin on early-stage atherosclerosis.

Methods: Mildly hyperglycemic ON-DP and normoglycemic ON-DR female mice fed an atherogenic diet for 20 weeks (8–28 weeks of age). During the feeding period, one group of each mouse line received metformin in drinking water (0.1%), while another group received water alone as control. Atherosclerotic lesion formation in the aortic sinus was quantitively analyzed from the oil red O-stained area of the serial sections.

Results: Metformin treatment did not affect food intake, body weight, and casual blood glucose levels within each mouse line during the 20-week feeding period. Nevertheless, metformin treatment significantly reduced atherosclerotic lesion formation in the ON-DP mice (59% of control), whereas no significant effect of metformin was observed in the lesion size of the ON-DR mice.

Conclusion: Metformin can attenuate early-stage atherogenesis in mildly hyperglycemic ON-DP mice. Pleiotropic effects of metformin, beyond its glucose-lowering action, may contribute to the antiatherogenic property in the early-stage atherosclerosis.

Basal-Bolus Insulin Therapy with Gla-300 During Hospitalization Reduces Nocturnal Hypoglycemia in Patients with Type 2 Diabetes Mellitus: A Randomized Controlled Study

INTRODUCTION

Although reduction in the incidence of nocturnal hypoglycemia, as estimated by symptom or self-monitored plasma glucose, was shown to be more pronounced with 300 units/mL insulin glargine (Gla-300) than with 100 units/mL insulin glargine (Gla-100) in type 2 diabetes patients, the exact frequency of nocturnal hypoglycemia estimated with continuous glucose monitoring (CGM) has not been reported.

METHODS

Forty patients with type 2 diabetes who were admitted for glycemic control with basal-bolus insulin therapy (BBT) were randomized into the Gla-100 and Gla-300 groups. Insulin doses were adjusted to maintain blood glucose levels within 100-120 mg/dL at each meal. Plasma glucose and C-peptide profiles were estimated serially after admission and before discharge. Daily CGM was also performed before discharge.

RESULTS

In the Gla-100 and Gla-300 groups, the mean duration of hospitalization was 15 ± 2 and 15 ± 1 days, respectively, and the mean basal insulin dose before discharge was 13 ± 7 and 15 ± 10 units, respectively. The dose of meal-time insulin was not different between the two groups. Compared with the Gla-300 group, the Gla-100 group had significantly lower nocturnal profiles of plasma glucose and C-peptide, but significantly higher frequency of CGM-estimated nocturnal hypoglycemia (10.7% ± 18.4% versus 1.2% ± 3.6%, P = 0.033).

CONCLUSION

In type 2 diabetic patients, reduction in the incidence of CGM-estimated nocturnal hypoglycemia by BBT under tightly controlled diet therapy was higher with Gla-300 than with Gla-100.

TRIAL REGISTRATION

UMIN clinical trials registry (UMIN000023360).

Repetitive Glucose Spikes Accelerate Atherosclerotic Lesion Formation in C57BL/6 Mice

Background

A number of epidemiological studies demonstrated that postprandial hyperglycemia is a risk factor for cardiovascular disease in individuals with impaired glucose tolerance. Although several laboratory studies have addressed the plausible causal role of postprandial acute hyperglycemia (glucose spikes) in the development of atherosclerosis, there is little convincing evidence in vivo whether the atherosclerotic lesion formation can be accelerated solely by glucose spikes. Here, we assessed the effect of repetitive glucose spikes on atherosclerotic lesion formation in mice.

Methods

Female C57BL/6 mice were fed an atherogenic diet from 8 to 28 weeks of age. During the atherogenic diet feeding period, the mice orally received a glucose solution (50 mg glucose/mouse; G group) or water (W group) twice daily, 6 days a week. Atherosclerotic lesion formation in the aortic sinus was quantitatively analyzed in serial cross-sections by oil red O staining.

Results

G group mice showed transient increases in blood glucose level (~5 mmol/L above W group), and the levels returned to levels similar to those in W group mice within 60 min. No significant differences in glucose tolerance, insulin sensitivity, and plasma lipid profiles were observed after the 20-week repetitive administration between the 2 groups. G group mice showed an approximately 4-fold greater atherosclerotic lesion size in the aortic sinus than W group mice. Gene expression levels of Cd68 and Icam1 in the thoracic aorta were higher in G group mice than in W group mice.

Conclusions

These results indicate that glucose spikes can accelerate atherosclerotic lesion formation, with little influence on other metabolic disorders. Repetitive glucose administration in wild-type mice may serve as a simple and useful approach to better understanding the causal role of glycemic spikes in the development of atherosclerosis.

Characterization of pancreatic islets in two selectively bred mouse lines with different susceptibilities to high-fat diet-induced glucose intolerance

Hereditary predisposition to diet-induced type 2 diabetes has not yet been fully elucidated. We recently established 2 mouse lines with different susceptibilities (resistant and prone) to high-fat diet (HFD)-induced glucose intolerance by selective breeding (designated selectively bred diet-induced glucose intolerance-resistant [SDG-R] and -prone [SDG-P], respectively). To investigate the predisposition to HFD-induced glucose intolerance in pancreatic islets, we examined the islet morphological features and functions in these novel mouse lines. Male SDG-P and SDG-R mice were fed a HFD for 5 weeks. Before and after HFD feeding, glucose tolerance was evaluated by oral glucose tolerance test (OGTT). Morphometry and functional analyses of the pancreatic islets were also performed before and after the feeding period. Before HFD feeding, SDG-P mice showed modestly higher postchallenge blood glucose levels and lower insulin increments in OGTT than SDG-R mice. Although SDG-P mice showed greater β cell proliferation than SDG-R mice under HFD feeding, SDG-P mice developed overt glucose intolerance, whereas SDG-R mice maintained normal glucose tolerance. Regardless of whether it was before or after HFD feeding, the isolated islets from SDG-P mice showed impaired glucose- and KCl-stimulated insulin secretion relative to those from SDG-R mice; accordingly, the expression levels of the insulin secretion-related genes in SDG-P islets were significantly lower than those in SDG-R islets. These findings suggest that the innate predispositions in pancreatic islets may determine the susceptibility to diet-induced diabetes. SDG-R and SDG-P mice may therefore be useful polygenic animal models to study the gene–environment interactions in the development of type 2 diabetes.

Effect of impaired glucose tolerance on atherosclerotic lesion formation: an evaluation in selectively bred mice with different susceptibilities to glucose intolerance

OBJECTIVE

Impaired glucose tolerance (IGT) is an independent risk factor for atherosclerotic cardiovascular disease. However, due to the lack of appropriate animal models, the underlying mechanisms for IGT-induced atherosclerosis remain to be elucidated in vivo. We recently used selective breeding to establish 2 mouse lines with distinctively different susceptibilities to diet-induced glucose intolerance, designated selectively bred diet-induced glucose intolerance-resistant (SDG-R) and SDG-prone (SDG-P), respectively. Here, we assessed atherosclerotic lesion formation in these mice.

METHODS

Female SDG-R and SDG-P mice were fed an atherogenic diet (AD; 1.25% cholesterol, 0.5% sodium cholate, and 36% energy as fat) for 20 weeks (8-28 weeks of age). Oral glucose tolerance tests were performed during the AD-feeding period. Atherosclerotic lesion formation was quantitatively analyzed in serial aortic sinus sections by oil red O staining. Plasma lipids were measured after the AD-feeding period.

RESULTS

Glucose tolerance was impaired in SDG-P mice as compared to SDG-R mice over the 20-week AD-feeding period. No significant differences were observed in any plasma lipid measurement between the 2 mouse lines. Aortic sinus atherosclerotic lesion formation in SDG-P mice was approximately 4-fold greater than that in SDG-R mice.

CONCLUSION

In 2 mouse lines with different susceptibilities to diet-induced glucose intolerance, IGT accelerated atherosclerotic lesion formation. These mice may therefore serve as useful in vivo models for investigating the causal role of IGT in the pathogenesis of atherosclerosis.

Medical relief activities conducted by Nippon Medical School in the acute phase of the Great East Japan Earthquake 2011

At 14:46 on March 11, 2011, the Great East Japan Earthquake and tsunami occurred off the coast of Honshu, Japan. In the acute phase of this catastrophe, one of our teams was deployed as a Tokyo Disaster Medical Assistance Team (DMAT) to Kudan Kaikan in Tokyo, where the ceiling of a large hall had partially collapsed as the result of the earthquake, to conduct triage at the scene: 6 casualties were assigned to the red category (immediate), which included 1 case of cardiopulmonary arrest and 1 of flail chest; 8 casualties in the yellow category (delayed); and 22 casualties in the green category (minor). One severely injured person was transported to our hospital. Separately, our medical team was deployed to Miyagi 2 hours after the earthquake in our multipurpose medical vehicle as part of Japan DMAT (J-DMAT). We were the first DMAT from the metropolitan area to arrive, but we were unable to start medical relief activities because the information infrastructure had been destroyed and no specific information had yet reached the local headquarters. Early next morning, J-DMAT decided to support Sendai Medical Center and search and rescue efforts in the affected area and to establish a staging care unit at Camp Kasuminome of the Japan Self-Defense Force. Our team joined others to establish the staging care unit. Because information was still confused until day 3 of the disaster and we could not adequately grasp onsite medical needs, our J-DMAT decided to provide onsite support at Ishinomaki Red Cross Hospital, a disaster base hospital, and relay information about its needs to the local J-DMAT headquarters. Although our medical relief teams were deployed as quickly as possible, we could not begin medical relief activities immediately owing to the severely damaged information infrastructure. Only satellite mobile phones could be operated, and information on the number of casualties and the severity of shortages of lifeline services could be obtained only through a "go and see" approach. Because there was no way to transmit or receive this vital information, disaster workers in the affected areas faced many challenges. For the future, network data links need to be made more resistant to infrastructure damage, and redundant or reach-back systems involving multitiered satellite, wireless, and radio frequency data links would provide definitive solutions. Such integrated systems should be designed around seamless connectivity based on an "always best connected" principle for maintaining communication quality.

High temperature ferromagnetism in GaAs-based heterostructures with Mn delta doping

We show that suitably designed magnetic semiconductor heterostructures consisting of Mn delta (delta)-doped GaAs and p-type AlGaAs layers, in which the locally high concentration of magnetic moments of Mn atoms are controllably overlapped with the two-dimensional hole gas wave function, realized remarkably high ferromagnetic transition temperatures (T(C)). A significant reduction of compensative Mn interstitials by varying the growth sequence of the structures followed by low-temperature annealing led to high T(C) up to 250 K. The heterostructure with high T(C) exhibited peculiar anomalous Hall effect behavior, whose sign depends on temperature.

Stereoselective synthesis of the neolignan, (+ )-dehydrodiconiferyl alcohol

A stereo controlled synthesis of the biologically active neolignan, (+)-dehydrodiconiferyl alcohol (1) was achieved. This synthetic method was also efficient for preparing its enantiomer and other derivatives with biological activity.

Generation of polyclonal antiserum against the growth hormone secretagogue receptor (GHS-R): evidence that the GHS-R exists in the hypothalamus, pituitary and stomach of rats

Growth hormone (GH) secretagogues (GHSs), which stimulate GH secretion, are synthetic compounds that act through the GHS receptor (GHS-R) which has been recently cloned. We raised an antiserum in a rabbit against a synthetic peptide corresponding to amino acid residues 248-260 of the third intracellular loop of the rat GHS-R. A competitive immunoassay showed that the antiserum had a specific affinity for the target peptide. To confirm the specificity of the antiserum, the GHS-R cDNA was stably expressed in COS-7 cells. In Western blot analysis, the band was detected at 44 kDa in the extracts from COS-7 cells expressing GHS-R (COS-7/tf3-2) but not in those from wild-type COS-7 cells. Furthermore, while COS-7/tf3-2 cells were strongly immunostained for GHS-R, no GHS-R-like immunoreactivity was observed in wild-type COS-7 cells. Immunoreactive bands were also observed at approximately 46 kDa in the extracts from rat hypothalamus, pituitary and stomach by Western blot analysis. These studies are the first to show the existence of GHS-R protein in the stomach. The antiserum for the GHS-R is sensitive and specific, and it would be useful for clarifying the roles of GHS/ghrelin.

Improved procedure for the enantiometric synthesis of 1-hydroxy/acetoxy-2,6-diaryl-3,7-dioxabicycl

Short enantiomeric syntheses of the 1-hydroxy/acetoxy-3,7-dioxabicyclo[3.3.0]octane lignans, paulownin, and (+)-phrymarin I and II, were accomplished by starting from the chiral synthon, (R)-(+)-3-hydroxybutanolide, and employing photocyclization as the key step.

Reduced growth hormone receptor messenger ribonucleic acid in an aged man with chronic malnutrition and growth hormone resistance

A severely malnourished 87-yr-old man presented with hypoglycemia. Serum GH levels were elevated, and serum levels of insulin-like growth factor I (IGF-I), IGF-binding protein-3, and GH-binding protein were extremely reduced. The patient's GH was biologically active. Administration of GH for 4 consecutive days resulted in a slight increment in serum IGF-I levels, but no elevation of serum IGF-binding protein-3. The expression of GH receptor messenger ribonucleic acid in the liver was greatly reduced. An autopsy revealed a Rathke's cleft cyst confined to the sella turcica. Immunohistochemical studies for GH showed that there was nothing to suggest a tumor overproducing GH. In addition, TSH levels were elevated in the presence of normal thyroid hormone levels, and there was a cluster of cells showing strong immunohistochemical staining for the TSH beta-subunit in the pituitary. In this patient, the decreased expression of GH receptor messenger ribonucleic acid in the liver may have been responsible for the GH resistance, which was probably caused by malnutrition.

Prohormone convertases 1 and 2 process ProPACAP and generate matured, bioactive PACAP38 and PACAP27 in transfected rat pituitary GH4C1 cells

Pituitary adenylate cyclase-activating polypetide (PACAP) exists in two amidated forms, PACAP38 and PACAP27, which are expressed in the magnocellular and parvocellular neurons of the paraventricular nucleus (PVN) and the magnocellular neurons of the supraoptic nucleus (SON) of the hypothalamus. The prohormone convertases PC1 and PC2, subtilisin-like PCs of the Kex2 family, are expressed in neuroendocrine cells. Immunocytochemistry and in situ hybridization of PC1 and PC2 in the hypothalamus have shown that PC1 and PC2 are also present in the PVN and SON. Therefore, it is possible that the precursor of PACAP is processed by PC1 and/or PC2 in the hypothalamic nuclei and then converted to its mature forms. To test this hypothesis, rat pituitary GH4C1 cells were supertransfected with human PACAP cDNA and either rat PC1 or PC2 cDNA. The acid extracts of these cells were analyzed by reversed-phase HPLC for proPACAP, PACAP38 and/or PACAP27 radioimmunoassays using three antibodies with different recognition sites, and then bioassayed for the ability to stimulate adenylate cyclase. The cells transfected with PACAP cDNA alone yielded PACAP-like immunoreactivity (PACAP-li) corresponding to molecular weights between 15 and 20 kDa without PACAP bioactivity. Cotransfection of these cells with PC1 or PC2 generated PACAP-li, which coeluted with synthetic PACAP38 and PACAP27, respectively. Western blot also revealed 4.5- and 3.0-kDa PACAP-li bands, which correspond to the molecular weights of PACAP38 and PACAP27, respectively. The HPLC fractions containing PACAP-li, which were coeluted with synthetic PACAP38 and PACAP27, showed marked bioactivities. These findings suggest that the precursor of PACAP expressed in the PVN and SON of the hypothalamus could be efficiently processed by PC1 and PC2, and then converted to mature, bioactive PACAP38 and PACAP27.

Testis-specific prohormone convertase PC4 processes the precursor of pituitary adenylate cyclase-activating polypeptide (PACAP)

The physiological substrate for proprotein convertase (PC) 4, which is expressed only in the testis, has remained unknown. Pituitary adenylate cyclase activating polypeptide (PACAP), originally isolated from the hypothalamus, exists as two amidated forms with 38 (PACAP38) and 27 (PACAP27) residues. PACAP-like immunoreactivity (PACAP-li) is found not only in the brain, but also in the peripheral tissues, and is especially abundant in the testis. Immunohistochemistry of the rat testis demonstrated strong PACAP-li in spermatids in the cap and acrosome phases. The nearly simultaneous expression of PC4 transcripts and PACAP-li in spermatids during spermatogenesis led to the hypothesis that PACAP precursor is processed by PC4. To investigate this possibility, rat pituitary GH4C1 cells were stably transfected with human PACAP cDNA, and some of these cells were co-transfected with mouse PC4 cDNA. The acid extracts of the cells were fractionated by reversed-phase HPLC. Each fraction was examined for PACAP-li using three antisera which recognize PACAP precursor, PACAP38 and/or PACAP27. Negligible PACAP-li that eluted with synthetic PACAP38 or PACAP27 was detected from cells transfected with PACAP cDNA; however, PC4 co-transfected cells showed marked PACAP-li peaks with the retention times for both PACAP38 and PACAP27. Moreover, Western blot analysis revealed immunostained bands, corresponding to the Mr for PACAP38 and PACAP27, in the PC4 co-transfected cells. Bioactivity, as indicated by stimulation of cAMP production in pituitary cell cultures, was found only in the extracts of PC4 co-transfected cells. These results provide evidence that PACAP precursor in the testis is a substrate for PC4. The processing of PACAP precursor by PC4 at a critical time in spermatogenesis suggests an important regulatory role of PC4 and PACAP in the maturation of germ cells in the testis.

Cushing's syndrome due to bilateral adrenocortical adenomas with different pathological features

A 48-year-old woman with Cushing's syndrome due to bilateral adrenocortical adenomas is reported. The patient presented with a typical Cushingoid appearance. The serum cortisol level was elevated with loss of the diurnal rhythm and the plasma adrenocorticotropic hormone (ACTH) level was undetectable. Dynamic testing showed no suppression of urinary 17-OHCS by high-dose dexamethasone and no stimulation by metyrapone. An abdominal computed tomography (CT) scan showed bilateral adrenal tumors. Bilateral adrenalectomy was performed. The right adrenal gland contained a tumor that was encapsulated and consisted mainly of compact cells. The surrounding cortex was atrophic. The left adrenal gland contained an encapsulated tumor composed predominantly of clear cells. There were numerous small adrenocortical nodules in the surrounding cortex. Immunohistochemical analysis of steroidogenic enzymes (P450scc, 3beta-HSD, P450c21, P450c17 and P450c11) was performed. Immunoreactivity of all the enzymes was intense in the compact cells of the right adrenocortical adenoma, while the adjacent non-neoplastic cortex was negative for the enzymes. In the left adrenal tumor, the immunoreactivity of 3beta-HSD was intense, while that of P450c17 was weak. In the adrenocortical nodules, 3beta-HSD activity was sporadically observed. G protein genes encoding Gs alpha and Gi2 were examined for activating mutations at codons 201 and 227 (Gs alpha) and codons 179 and 205 (Gi2 alpha) in the bilateral adrenal tumors, but no mutations were found. The bilateral adenomas of this patient showed marked differences in microscopic and immunohistochemical studies, suggesting that the capacity of steroidogenesis differs between the right and left tumors.

Response of respiratory epithelium of BN and F344 rats to formaldehyde inhalation

BN rats are well-known for their high capacity for IgE production and hyperresponsiveness to exposure to allergens or other chemicals. We examined the histological changes in the nasal cavity, trachea and lungs of BN and F344 rats after the inhalation of aerosol formaldehyde (HCHO), which exerts direct toxic effects on the respiratory system. The incidence of clinical signs such as sneezing and abnormal respiration in HCHO-treated F344 rats was higher than that in HCHO-treated BN rats. The mean body weight of HCHO-treated F344 rats apparently decreased in comparison with control F344 rats, but that of HCHO-treated BN rats was not significantly different from that of control BN rats. Changes such as squamous metaplasia, stratification, degeneration and desquamation were observed by light microscopy in nasal, tracheal and bronchial mucosa in the lungs of the HCHO-treated F344 rats. In the HCHO-treated BN rats, similar but milder lesions were restricted to the nasal mucosa. Scanning electron microscopic observation supported these light microscopic observations. These results suggest that BN rats have lower sensitivity to HCHO inhalation than F344 rats.

Localization and gene expression of the receptor for pituitary adenylate cyclase-activating polypeptide in the rat brain

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a recently identified member of the secretin/vasoactive intestinal polypeptide (VIP) family. There are at least two types of receptor for PACAP: type I (PACAPR), which specifically binds PACAP; and type II (VIP/PACAPR), which binds both PACAP and VIP. The localization of PACAPR in the rat brain was determined by in situ hybridization and immunocytochemistry. We raised antisera against a synthetic peptide that corresponds to the carboxy-terminal cytoplasmic domain which is found in all subtypes of PACAPR in order to localize PACAPR-like immunoreactivity (PACAPR-LI) in the rat brain. In general, the distribution of PACAPR-LI correlated well with the distribution of PACAPR transcripts. Particularly strong PACAPR mRNA expression was detected in the olfactory bulb, hippocampus, cerebellum and hypothalamus and moderate labeling was detected in other scattered regions. At the cellular level, PACAPR-LI appeared to be concentrated predominantly in neuronal perikarya and dendrites. At the ultrastructural level, strong immunostaining for the PACAPR was found in plasma membranes, rough endoplasmic reticulum, cytoplasmic matrix, and at synapses. This study provides the basis for a better understanding of the functions of PACAP in the rat brain.

Ontogeny of pituitary adenylate cyclase activating polypeptide and its receptor mRNA in the mouse brain

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide which was first isolated from ovine hypothalamic tissue by screening for pituitary adenylate cyclase stimulating activity. Our previous data showed that radioimmunoassayable PACAP and PACAP-binding sites were detected in the whole rat brain as early as embryonic day 14(E14). In order to understand more precisely the developmental pattern of the synthesis of PACAP and its receptors in the brain, we studied the expression of PACAP and its receptor genes in the prenatal and postnatal mouse brain using RNase protection assay. The mRNAs for both PACAP and its receptor were detected as early as 9.5 days of gestation (E9.5) in the whole head of mouse embryos. The levels of PACAP mRNA in the brain increased during the prenatal period peaking at postnatal day 0 (P0). On the other hand, the levels of PACAP receptor mRNA gradually increased after E9.5. The levels sharply increased at P6 (479.0 +/- 82.5% of P0 levels), and then fell to the P3 levels at P10. These data together with our previous study on the ontogeny of PACAP immunoreactivity and its binding sites in the rat brain support the view that PACAP plays an important regulatory role in the development of brain.

Oxidation of acetophenone by Aspergillus species and their possible contribution to Katsuobushi flavor

Acetophenone was converted to phenol by A. glaucus MA0200. Production of phenol, which has a pungent flavor, seemed to give a contrary effect on the creation of flavor of molded Katsuobushi. Production of phenol is the process of degradation of acetophenone, also with a pungent flavor. It would play a role in the decreasing of the pungent flavor of Katsuobushi.

Effect of hypophysectomy on pituitary adenylate cyclase activating polypeptide gene expression in the rat hypothalamus

Pituitary adenylate cyclase activating polypeptide (PACAP) is a new member of the secretin/glucagon/vasoactive intestinal peptide (VIP) family. It stimulates adenylate cyclase in cultured rat pituitary cells, which have PACAP-specific receptors and expression of pituitary hormones. Therefore, PACAP is considered as a hypophysiotropic hormone. If so, there might be a feedback regulatory mechanism between pituitary hormones and hypothalamic PACAP. In the present study, we used nuclear run-on and RNase protection assays to examine whether transcription of the PACAP gene in the rat hypothalamus would change after hypophysectomy. PACAP levels in the hypothalamus were also determined by radioimmunoassay. The transcriptional rate of the PACAP gene and PACAP mRNA content decreased 1 and 2 weeks after hypophysectomy. Radioimmunoassayable PACAP levels in the hypothalamus also decreased after hypophysectomy. These findings suggest that the reduced rate of PACAP gene transcription after hypophysectomy causes the decreased mRNA and peptide levels in the hypothalamus. Replacement with GH, PRL, T4, corticosterone, and testosterone significantly restored PACAP mRNA levels in hypophysectomized rats to those in control animals. The results suggest that feedback regulation takes place between pituitary hormones or pituitary-dependent factors and hypothalamic PACAP.

Effect of hypophysectomy on pituitary adenylate cyclase-activating polypeptide gene expression in the rat testis

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a member of the secretin/glucagon/vasoactive intestinal peptide (VIP) family. Our immunohistochemical and in situ hybridization histochemical studies indicated that PACAP-like immunoreactivity (PACAP-LI) and its mRNA were present in the germ cells in the rat testis. Because the testicular function is regulated by the pituitary gonadotropins, effect of hypophysectomy on the PACAP gene expression was investigated in the rat testis as an attempt to reveal the regulation of the testicular PACAP by the pituitary. The levels of testicular PACAP mRNA, which were determined by RNase protection assay, increased 2 weeks after hypophysectomy. In contrast, the levels of radioimmunoassayable PACAP decreased 2 weeks after the surgery. Immunohistochemistry showed that hypophysectomy did not change the distribution of PACAP-LI, although the number of immunopositive cells was markedly reduced after hypophysectomy. The replacement treatments of hypophysectomized animals with FSH or LH+FSH restored testicular PACAP mRNA to the levels in the control animals. On the other hand, all of these treatments (testosterone, LH, FSH, or LH+FSH) significantly increased radioimmunoassayable PACAP in the hypophysectomized rat testis. The results suggest that both testicular PACAP and its mRNA expression are regulated by the hypothalamic-pituitary-gonadal activity, and that FSH may play a major role in this regulation.

Transcriptional activity of a mutant thyroid hormone receptor beta in a family with generalized resistance to thyroid hormone

We previously reported a family with generalized resistance to thyroid hormone (GRTH) which had a point mutation with codon 448 CCT (proline) being converted to ACT (threonine) in the thyroid hormone receptor (TR) beta. To characterize functional properties of the mutant TR beta, transient expression studies were performed in COS cells. A double stranded oligonucleotide encompassing thyroid hormone response element (TRE) derived from the rat GH gene was synthesized. We constructed chloramphenicol acetyl transferase (CAT) plasmid containing the thymidine kinase promoter under the control of the rat GH TRE. T3 induction of CAT activity by the mutant TR beta was significantly reduced as compared with that of the normal TR beta. This was observed in the presence of 0.5-50 nM T3, but not at 500 nM T3. When the normal and mutant TR beta were cotransfected, the mutant TR beta inhibited gene activation regulated by the normal TR beta. However, a high molar excess was necessary to significantly inhibit the function of the normal receptor. Additionally, the binding of in vitro synthesized mutant TR beta to TRE was preserved.

A point mutation in the 3,5,3'-triiodothyronine-binding domain of thyroid hormone receptor-beta associated with a family with generalized resistance to thyroid hormone

A tight linkage between generalized resistance to thyroid hormone (GRTH) and the thyroid hormone receptor-beta (TR beta) gene is indicated. We evaluated a family with GRTH for the TR beta gene. We found that a new point mutation, consisting of a cytosine to adenine replacement at nucleotide position 1642, resulted in substitution in codon 448 in the T3-binding domain of TR beta. This base substitution was found in only one allele of affected members, but not in unaffected members of the family. The in vitro translation products of this mutant TR beta gene demonstrated significantly reduced T3-binding affinity. Previously, others have reported a kindred with GRTH, in that the same codon was subjected to proline to histidine replacement due to a mutation consisting of a cytosine to adenine replacement at nucleotide position 1643. There appeared to be a significant phenotypic difference between our kindred and that described by others.