Acute repeated cage exchange stress modifies urinary stress and plasma metabolic profiles in male mice.

Exposure to a novel environment is psychologically and physically stressful for humans and animals. The response has been reported to involve enhanced sympathetic nervous system activity, but changes in nutrient levels under stress are not fully understood. As a form of exposure to a novel environment, repeated cage exchange (CE, four times at 2-h intervals for 8 h from 08:00 h) during the light phase with no restraint on movement was applied to A/J mice, a strain particularly prone to stress. Body temperature was measured with a temperature-sensing microchip implanted in the interscapular region. The stress conditions and anxiety level were evaluated by measuring urinary catecholamines and corticosterone and by performing an anxiety-like behavior test, respectively. Major nutrients such as glucose, fatty acids, and amino acids in the plasma were also examined. CE mice showed a significant increase in body temperature with each CE. They also showed a significantly greater reduction of body weight change, more water intake, and higher levels of urinary catecholamines and corticosterone and anxiety-like behavior score than control mice. The model revealed a significantly lower plasma glucose level and higher levels of several essential amino acids, such as branched-chain amino acids and phenylalanine, than those of control mice. Meanwhile, free fatty acids and several amino acids such as arginine, aspartic acid, proline, threonine, and tryptophan in both sets of mice were significantly decreased from the corresponding levels at 08:00 h, while similar plasma levels were exhibited between mice with and without CE. In conclusion, repeated CE stress was associated with changes in glucose and amino acids in plasma. Although further study is needed to clarify how these changes are specifically linked to anxiety-like behavior, this study suggests the potential for nutritional intervention to counter stress in humans exposed to novel environments.

Survey of Smokers Among Workers at One Facility: A Cross-sectional Study With Propensity Score Matching.

BACKGROUND/AIM: Smoking has been reported to be a risk factor for a variety of diseases. In Japan, the Brief Job Stress Questionnaire (BJSQ) has been administered by the Ministry of Health, Labour and Welfare since December 2015, but few reports have focused on its relationship with smoking. We investigated the current situation of smokers among staff of Kagoshima University who underwent a medical check-up. PATIENTS AND METHODS: Of 2,478 people who underwent a medical check-up in May and June 2021, we targeted 2,237 workers who reported whether they smoked. We examined results of the medical check-up and BJSQ and the background of smokers (n=139, 6.2%). We compared smokers and non-smokers (n=2,098) using propensity score matching (PSM) for sex, age, drinking habits, medication for dyslipidaemia, and overtime working hours at a 1:1 ratio. RESULTS: The results showed that white blood cell count (p=0.044), platelet count (p<0.001), glutamyl transferase (p=0.023), and triglyceride (p=0.027) were significantly higher among current smokers in comparison with current non-smokers. Smokers reported significantly more stress than non-smokers in terms of social support (p=0.027). CONCLUSION: As a result of PSM, several blood test items related to non-communicable diseases (lifestyle-related diseases) showed high values in current smokers, and these individuals reported significantly more stress than non-smokers. According to the emphasis on group analysis in the Total Health Promotion Plan revised in 2020, our findings can be helpful in enhancing smoking cessation programs in the workplace.

Clinical features of obscure gastrointestinal bleeding undergoing capsule endoscopy: A retrospective cohort study.

BACKGROUND: Capsule endoscopy has been widely used to investigate obscure gastrointestinal bleeding (OGIB) in the small intestine since its approval in 2001. However, the clinical features of OGIB remain unclear. AIM: We retrospectively examined the clinical features and risk factors of OGIB in patients who underwent capsule endoscopy in our hospital. METHODS: We included 420 of the 431 patients who underwent capsule endoscopy from June 2014 to May 2021, in whom the small intestine could be observed. We retrospectively compared the clinical features and treatment of OGIB cases, with or without active small bowel bleeding (n = 173), with other cases (n = 247). Patient sex, age, diabetes mellitus, and heart failure histories were matched for the analysis. RESULTS: The male/female ratio was 247/173 and the average age was 51.54 years. In multivariate analysis, the use of direct oral anticoagulants was significant (P = 0.016), and vascular lesions (P = 0.018) were observed in OGIB cases. When OGIB cases with and without active small bowel bleeding were compared, serum albumin level was lower in cases with active bleeding (P = 0.031). When treatment of OGIB cases were compared, those without vascular lesions could be treated conservatively (P = 0.0047). In the 1:1 propensity score matching analysis, serum creatinine level was elevated in cases of active bleeding (P = 0.029), and cases without vascular lesions were treated conservatively (P = 0.010). CONCLUSIONS: Use of direct oral anticoagulants is frequently associated with OGIB. OGIB patients without vascular lesions may be treated conservatively.

Comparison of dipstick and quantitative tests for proteinuria and hematuria in middle-aged, male Japanese employees: A single-center study.

BACKGROUND AND AIMS: The early and reliable detection of chronic kidney disease is important. In the present study, we aimed to compare the diagnostic results for proteinuria and hematuria between the dipstick test used in primary occupational health examinations and the quantitative tests used in more thorough examinations in clinics. METHODS: We conducted a single-center observational study of male staff (N = 573) at Kagoshima University who underwent a health examination in 2017. Both dipsticks and biochemical methods were used to assess proteinuria and hematuria. RESULTS: For the dipstick test, the sensitivity, specificity, and positive predictive value were 55.6%, 92.4% and 10.4% for proteinuria, and 64.3%, 98.3% and 66.7% for hematuria, respectively. Four participants for whom false-negative results were obtained using dipsticks for proteinuria, and two of these had 3+ urinary glucose. CONCLUSION: Qualitative tests for proteinuria and hematuria had low sensitivities and positive predictive values. Therefore, for the early and reliable detection of chronic kidney disease, the use of quantitative urine tests should be considered during occupational health examinations.

Higher Branched-chain Amino Acids and Lower Serine Exist in the Plasma of Nondiabetic Mice: A Comparison Between High- and Low-protein Diet Conditions.

BACKGROUND/AIM: The effects of dietary protein and carbohydrate content on the plasma amino acid profile of patients with diabetes are not fully understood. Therefore, we examined whether there are effects of diets with differing proportions of protein and carbohydrate on the plasma amino acid concentrations of control (CT) mice and mice with type 2 diabetes (db). MATERIALS AND METHODS: We used db mice as an animal model of type 2 diabetes which are genetically deficient in leptin receptor. Diets with differing proportions of protein and carbohydrates (L diet: low protein/carbohydrate ratio, H diet: high protein/carbohydrate ratio) were supplied. db Mice were fed with a restriction on the basis of the consumption by CT-L mice, such that equivalent amounts of energy and fat were consumed. In CT mice fed the L or H diets, there was no significant difference in ad libitum food intake. RESULTS: There were significant interactions between diet and genotype with respect to water intake, urine volume, urinary glucose concentration, and plasma isoleucine, leucine, valine, branched-chain amino acids, and serine concentrations. db-H mice showed significantly higher water intake, urine volume, and urinary glucose than db-L mice. db Mice fed the L or H diets had similar plasma amino acid profiles, except for valine. In contrast, CT-H mice showed significantly higher valine and branched-chain amino acids and lower serine concentrations than CT-L mice. Thus, the CT-H mice were more similar to db mice fed either of the diets. CONCLUSION: There were different effects of the dietary protein or carbohydrate content on the plasma amino acid profiles between nondiabetic and diabetic mice. In particular, the profiles in nondiabetic conditions were different between the low- and high-protein diet conditions.

Inhibition of ABL1 tyrosine kinase reduces HTLV-1 proviral loads in peripheral blood mononuclear cells from patients with HTLV-1-associated myelopathy/tropical spastic paraparesis.

Human T-cell leukemia virus type 1 (HTLV-1) causes incurable adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Patients with HAM/TSP have increased levels of HTLV-1-infected cells compared with asymptomatic HTLV-1 carriers. However, the roles of cellular genes in HTLV-1-infected CD4+ T cells await discovery. We performed microarray analysis of CD4+ T cells from HAM/TSP patients and found that the ABL1 is an important gene in HAM/TSP. ABL1 is a known survival factor for T- and B-lymphocytes and is part of the fused gene (BCR-ABL) known to be responsible for chronic myelogenous leukemia (CML). ABL1 tyrosine kinase inhibitors (TKIs), including imatinib, nilotinib, and dasatinib, are used clinically for treating CML. To evaluate whether ABL1 is indeed important for HAM/TSP, we investigated the effect of TKIs on HTLV-1-infected cells. We developed a propidium monoazide-HTLV-1 viability quantitative PCR assay, which distinguishes DNA from live cells and dead cells. Using this method, we were able to measure the HTLV-1 proviral load (PVL) in live cells alone when peripheral blood mononuclear cells (PBMCs) from HAM/TSP cases were treated with TKIs. Treating the PBMCs with nilotinib or dasatinib induced significant reductions in PVL (21.0% and 17.5%, respectively) in live cells. Furthermore, ABL1 siRNA transfection reduced cell viability in HTLV-1-infected cell lines, but not in uninfected cell lines. A retrospective survey based on our clinical records found a rare case of HAM/TSP who also suffered from CML. The patient showed an 84.2% PVL reduction after CML treatment with imatinib. We conclude that inhibiting the ABL1 tyrosine kinase specifically reduced the PVL in PBMCs from patients with HAM/TSP, suggesting that ABL1 is an important gene for the survival of HTLV-1-infected cells and that TKIs may be potential therapeutic agents for HAM/TSP.

Nonalcoholic fatty liver disease is associated with both subcutaneous and visceral adiposity: A cross-sectional study.

Nonalcoholic fatty liver disease (NAFLD) is recognized as a hepatic manifestation of metabolic syndrome because of the association with visceral obesity. However, the association between NAFLD and subcutaneous fat accumulation remains unclear.The study population included 3197 participants in regular health checkups, who were both hepatitis B virus surface antigen and hepatitis C virus antibody-negative, and consumed <20 g of alcohol per day. They were divided according to 4 quantiles of subcutaneous fat area (SFA) and visceral fat area (VFA) on computed tomography. Fatty liver was diagnosed using ultrasonography (FL-US).The prevalence of FL-US increased across the SFA categories, even after adjusting for the VFA, in both men (P < .001) and women (P < .001). This significant association between FL-US and the SFA was already detected from the second SFA quantile. It is noteworthy that the mean body mass index (BMI) of the subjects in the second quantile was 23.7 kg/m in men and 22.6 kg/m in women. Independent positive associations were observed between alanine aminotransferase elevation, and both the SFA and VFA in men, while gamma glutamyl transpeptidase elevation was independently associated with the VFA, but not the SFA, in both men and women. Similarly, the components of metabolic syndrome were independently associated with the VFA, but were less strongly associated (or not associated at all) with the SFA.This cross-sectional study suggests that NAFLD is independently associated with both visceral and subcutaneous adiposity ab initio, which is a characteristic that distinguishes NAFLD from other components of metabolic syndrome.

Dynamics of Soluble Thrombomodulin and Circulating miRNAs in Patients with Atrial Fibrillation Undergoing Radiofrequency Catheter Ablation.

Atrial fibrillation (AF) is the most common cardiac arrhythmia in the world and has a high risk of thromboembolism. The most effective approach, catheter ablation, requires evaluation by electrocardiography. The aim of our study was to investigate novel clinical markers that predict restoration of sinus rhythm (SR) after catheter ablation. Seventy-eight consecutive patients with AF underwent catheter ablation and were separated into 2 groups: restored SR and recurrent AF. The levels of 4 blood proteins (serum or plasma) and 3 mature microRNAs (miRNAs) and their primary miRNAs (pri-miRNAs) in serum were measured before and after ablation, and the associations between each parameter were analyzed statistically. Soluble thrombomodulin (s-TM) and plasminogen activator inhibitor-1 (PAI-1) levels increased above baseline after ablation in both the restored SR (s-TM 11.55 [2.92] vs 13.75 [3.38], P < .001; PAI-1 25.74 [15.25] vs 37.79 [19.56], P < .001) and recurrent AF (s-TM 10.28 [2.78] vs 11.67 [3.37], P < .001; PAI-1 26.16 [15.70] vs 40.74 [22.55], P < .001) groups. Levels of C-reactive protein and asymmetric dimethylarginine were not significantly changed. Pri-miR-126 levels significantly decreased after ablation in the recurrent AF group, but the other miRNAs and pri-miRNAs did not. The measurement of s-TM and pri-miR-126 in blood was a useful tool to reflect the condition of AF patients with catheter ablation.

Pivotal role of inter-organ aspartate metabolism for treatment of mitochondrial aspartate-glutamate carrier 2 (citrin) deficiency, based on the mouse model.

Previous studies using citrin/mitochondrial glycerol-3-phosphate (G3P) dehydrogenase (mGPD) double-knockout mice have demonstrated that increased dietary protein reduces the extent of carbohydrate-induced hyperammonemia observed in these mice. This study aimed to further elucidate the mechanisms of this effect. Specific amino acids were initially found to decrease hepatic G3P, or increase aspartate or citrulline levels, in mGPD-knockout mice administered ethanol. Unexpectedly, oral glycine increased ammonia in addition to lowering G3P and increasing citrulline. Subsequently, simultaneous glycine-plus-sucrose (Gly + Suc) administration led to a more severe hyperammonemic state in double-KO mice compared to sucrose alone. Oral arginine, ornithine, aspartate, alanine, glutamate and medium-chain triglycerides all lowered blood ammonia following Gly + Suc administration, with combinations of ornithine-plus-aspartate (Orn + Asp) or ornithine-plus-alanine (Orn + Ala) suppressing levels similar to wild-type. Liver perfusion and portal vein-arterial amino acid differences suggest that oral aspartate, similar to alanine, likely activated ureagenesis from ammonia and lowered the cytosolic NADH/NAD+ ratio through conversion to alanine in the small intestine. In conclusion, Gly + Suc administration induces a more severe hyperammonemic state in double-KO mice that Orn + Asp or Orn + Ala both effectively suppress. Aspartate-to-alanine conversion in the small intestine allows for effective oral administration of either, demonstrating a pivotal role of inter-organ aspartate metabolism for the treatment of citrin deficiency.

Diurnal Variation of Melatonin Concentration in the Cerebrospinal Fluid of Unanesthetized Microminipig.

BACKGROUND/AIM: The aim of this study was to develop a method for sequentially collecting cerebrospinal fluid (CSF) from an unanesthetized microminipig, which shares many physiological and anatomical similarities with humans, such as diurnality, and investigate the diurnal variation of melatonin concentration in the CSF. MATERIALS AND METHODS: A catheter was placed percutaneously into the subarachnoid space of an anesthetized animal, and the tip of the catheter was placed into the cisterna magna under X-ray. We then sequentially collected CSF at light-on and -off times from the unanesthetized animal for several weeks. After catheter placement, a period of one week or more was necessary to relieve the contamination of RBCs in the CSF. RESULTS: A higher melatonin level in the CSF was noted during lights-off time, and the level was higher than that in the serum. CONCLUSION: This model of sequential collection of CSF will contribute to research in brain functions.

Effects of Diets with Different Proportions of Protein/Carbohydrate on Retinal Manifestations in db Mice.

BACKGROUND/AIM: Diabetic nephropathy is aggravated by a higher intake of total protein. The effects of diets with different proportions of protein and carbohydrate on diabetic retinopathy in db mice, a type-2 diabetes animal model, were examined, as well as diabetic nephropathy. MATERIALS AND METHODS: Control and db mice at 5 weeks of age were fed the diets (% energy of protein/carbohydrate/fat; L-diet: 12/71/17; H-diet: 24/59/17) under ad libitum conditions and pair-feeding conditions for 6 weeks, respectively. RESULTS: Mice fed the H-diet showed significantly greater retinal thickness by optical coherence tomography, and lower mRNA levels of angiotensinogen. Comparing combinations of diets and genotypes, db-H mice showed significantly higher mRNA levels of angiotensin-converting enzyme, advanced glycosylation end product-specific receptor, and cluster of differentiation molecule 11b (a microglial marker) than db-L mice. CONCLUSION: Dietary protein and carbohydrate proportions influenced retinal manifestations, including retinal thickness and gene expression in control and diabetic mice.

Food Intake and Core Body Temperature of Pups and Adults in a db Mouse Line Deficient in the Long Form of the Leptin Receptor without Misty Mutation.

Different involvement of leptin signaling in food intake (FI) and body temperature (BT) in pups and adults has been suggested. However, the leptin receptor (Lepr) long-form-deficient (db) mouse line has not been fully examined in pups. In the most available db mouse line, wild-type (WT) mice have a mutation in the dedicator of cytokinesis 7 gene, named misty, which was recently revealed to be involved in neuronal development. Therefore, we established a line of db mice without the misty mutation using natural mating. Adult (8 weeks of age) homozygous db/db mice displayed significantly higher core body weight (BW) and FI and significantly lower core BT than WT mice. However, postnatal (2 weeks of age) db/db mice displayed similar BW and milk intake and significantly lower core BT than WT mice. Correspondingly, adult and postnatal db/db mice exhibited altered mRNA levels of hypothalamic orexigenic and anorexigenic peptide in adults but not in pups. Additionally, db/db mice displayed significantly lower mRNA levels of brown adipose tissue uncoupling protein 1 at both ages. In conclusion, the db mouse line without the misty mutation clearly showed the different involvements of the Lepr long form in FI and BT in pups and adults.

Effects of Dietary and Lighting Conditions on Diurnal Locomotor Activity and Body Temperature in Microminipigs.

The effects of dietary and lighting conditions on diurnal rhythm of locomotor activity (LA) and body temperature (BT) using four adult male microminipigs were investigated. Different feeding times, diet and lighting conditions were applied sequentially for 3 weeks in each phase as follows: Phase I: Morning mealtime, normal diet, 12-h lights on; phase II: mealtime changed to afternoon; phase III: diet changed to high-fat diet; phase IV: lighting changed to 20-h on; and phase V: phase I repeated. LA was measured by an actigraph which was worn on the body of each pig. A BT recording module (Thermochron Type-SL) was implanted in the neck subcutaneously. Phase II increased BT compared with phase I. Phase III increased LA and BT compared with phase II. Phase IV increased LA compared with phase III. LA in phase V was higher compared with phase I. These results can be extrapolated to other diurnal animals such as humans. This study provides an example of the effects of diet and lighting on biological activities in microminipigs under low-invasive procedures measuring LA and BT, leading to low variations in these measures.

Potential predictors of susceptibility to occupational stress in Japanese novice nurses - a pilot study.

BACKGROUND: Occupational stress is a known factor behind employee resignations; thus, early identification of individuals prone to such stress is important. Accordingly, in this pilot study we evaluated potential predictors of susceptibility to occupational stress in Japanese novice nurses. METHODS: Forty-two female novice nurses at Kagoshima University Hospital were recruited for the study population. Each underwent physical health and urinary examinations, and completed a lifestyle questionnaire at the time of job entry. Each also completed a Brief Job Stress Questionnaire (BJSQ), related to mental health status, at job entry and 5 months post-entry. Psychological stress, somatic symptoms, and combined BJSQ scores were determined for each time point. RESULTS: All three stress condition scores had significantly decreased at 5 months post-entry, suggesting occupational stress. Systolic blood pressure (r = -0.324, p < 0.05) and urinary sodium (r = -0.313, p < 0.05) were significantly negatively correlated with combined BJSQ score at 5 months post-entry. Post-entry stress condition scores were significantly low in subjects reporting substantial 1-year body weight change (≤ ± 3 kg) and short times between dinner and bedtimes (≤2 h), though baseline stress condition scores were not. Urinary sodium concentration, 1-year body weight change, and pre-sleep evening meals were then targeted for multivariate analysis, and confirmed as independent explanatory variables for post-entry stress condition scores. CONCLUSIONS: One-year body weight change, times between dinner and bedtimes, and urinary sodium concentration are promising potential predictors of susceptibility to occupational stress, and should be further investigated in future research. TRIAL REGISTRATION: ISRCTN ISRCTN17516023. Retrospectively registered 7 December 2016.

Deteriorated glucose metabolism with a high-protein, low-carbohydrate diet in db mice, an animal model of type 2 diabetes, might be caused by insufficient insulin secretion.

PURPOSE: We previously showed the deleterious effects of increased dietary protein on renal manifestations and glucose metabolism in leptin receptor-deficient (db) mice. Here, we further examined its effects on glucose metabolism, including urinary C-peptide. We also orally administered mixtures corresponding to low- or high-protein diets to diabetic mice. METHODS: In diet experiments, under pair-feeding (equivalent energy and fat) conditions using a metabolic cage, mice were fed diets with different protein content (L diet: 12 % protein, 71 % carbohydrate, 17 % fat; H diet: 24 % protein, 59 % carbohydrate, 17 % fat) for 15 days. In oral administration experiments, the respective mixtures (L mixture: 12 % proline, 71 % maltose or starch, 17 % linoleic acid; H mixture: 24 % proline, 59 % maltose or starch, 17 % linoleic acid) were supplied to mice. Biochemical parameters related to glucose metabolism were measured. RESULTS: The db-H diet mice showed significantly higher water intake, urinary volume, and glucose levels than db-L diet mice but similar levels of excreted urinary C-peptide. In contrast, control-H diet mice showed significantly higher C-peptide excretion than control-L diet mice. Both types of mice fed H diet excreted high levels of urinary albumin. When maltose mixtures were administered, db-L mixture mice showed significantly higher blood glucose after 30 min than db-H mixture mice. However, db mice administered starch-H mixture showed significantly higher blood glucose 120-300 min post-administration than db-L mixture mice, although both groups exhibited similar insulin levels. CONCLUSIONS: High-protein, low-carbohydrate diets deteriorated diabetic conditions and were associated with insufficient insulin secretion in db mice. Our findings may have implications for dietary management of diabetic symptoms in human patients.

Birth of Cloned Microminipigs Derived from Somatic Cell Nuclear Transfer Embryos That Have Been Transiently Treated with Valproic Acid.

In our previous study, we found that treatment of miniature pig somatic cell nuclear transfer (SCNT) embryos with 4 mM valproic acid (VPA), a histone deacetylase inhibitor, for 48 hours after activation enhanced blastocyst formation rate and octamer-binding transcription factor-3/4 (Oct-3/4) gene expression at the late blastocyst stage; however, the production of viable cloned pups failed, when those VPA-treated SCNT embryos were transferred to recipients. This failure suggests that the present VPA treatment is suboptimal. In the present study, we explored the optimal conditions for VPA to have beneficial effects on the development of SCNT embryos. When miniature pig SCNT embryos were treated with 8 mM VPA for 24 hours after activation, both the rates of blastocyst formation and blastocysts expressing the Oct-3/4 gene were significantly (p < 0.05) improved. A similar increase in blastocyst formation was also observed when microminipig-derived cells were used as SCNT donors. Five cloned piglets were obtained after the transfer of 152 microminipig SCNT embryos that had been treated with 8 mM VPA for 24 hours. The results indicated that a short duration of treatment with VPA improves the development of both miniature pig and microminipig SCNT embryos, possibly via an enhanced reprogramming mechanism.

Carnitine deficiency induces a short QT syndrome.

BACKGROUND: Short QT syndrome is associated with an increased risk of cardiac arrhythmias and unexpected sudden death. Until now, only mutations in genes encoding the cardiac potassium and calcium channels have been implicated in early T-wave repolarization. OBJECTIVE: The purpose of this study was to confirm a relationship between a short QT syndrome and carnitine deficiency. METHODS: We report 3 patients affected by primary systemic carnitine deficiency and an associated short QT syndrome. Ventricular fibrillation during early adulthood was the initial symptom in 1 case. To confirm the relationship between carnitine, short QT syndrome, and arrhythmias, we used a mouse model of carnitine deficiency induced by long-term subcutaneous perfusion of MET88. RESULTS: MET88-treated mice developed cardiac hypertrophy associated with a remodeling of the mitochondrial network. The continuous monitoring of electrocardiograms confirmed a shortening of the QT interval, which was negatively correlated with the plasma carnitine concentration. As in humans, such alterations coincided with the genesis of ventricular premature beats and ventricular tachycardia and fibrillation. CONCLUSION: Altogether, these results suggest that long-chain fatty acid metabolism influence the morphology and the electrical function of the heart.

[Experimental Approach to Analysis of the Relationship between Food Environments and Lifestyle-Related Diseases, Including Cardiac Hypertrophy, Fatty Liver, and Fatigue Symptoms].

The food habit is involved in the onset and development of lifestyle-related diseases. In this review I would like to describe a historical case of vitamin B1 deficiency, as well as our case study of fatty acid metabolism abnormality due to carnitine deficiency. In history, the army and navy personnel in Japan at the end of the 19th century received food rations based on a high-carbohydrate diet including white rice, resulting in the onset of beriberi. An epidemiological study by Kenkan Takaki revealed the relationship between the onset of beriberi and rice intake. Then, Takaki was successful in preventing the onset of beriberi by changing the diet. However, the primary cause had yet to be elucidated. Finally, Christian Eijkman established an animal model of beriberi (chickens) showing peripheral neuropathy, and he identified the existence of an anti-beriberi substance, vitamin B1. This is an example of the successful control of a disease by integrating the results of epidemiological and experimental studies. In our study using a murine model of fatty acid metabolism abnormality caused by carnitine deficiency, cardiac abnormality and fatty liver developed depending on the amount of dietary fat. In addition, the mice showed disturbance of orexin neuron activity related to the sleep-arousal system, which is involved in fatigue symptoms under fasting condition, one of the states showing enhanced fatty acid metabolism. These findings suggest that fatty acid toxicity is enhanced when the mice are more dependent on fatty acid metabolism. Almost simultaneously, a human epidemiological study showed that narcolepsy, which is caused by orexin system abnormality, is associated with the polymorphism of the gene coding for carnitine palmitoyltransferase 1B, which is involved in carnitine metabolism. To understand the pathological mechanism of fatty acid toxicity, not only an experimental approach using animal models, but also an epidemiological approach is necessary. The results will be applied to preventing and treating lifestyle-related diseases associated with fatty acid metabolism abnormality.

Mechanism for increased hepatic glycerol synthesis in the citrin/mitochondrial glycerol-3-phosphate dehydrogenase double-knockout mouse: Urine glycerol and glycerol 3-phosphate as potential diagnostic markers of human citrin deficiency.

The mitochondrial aspartate-glutamate carrier isoform 2 (citrin) and mitochondrial glycerol-3-phosphate dehydrogenase (mGPD) double-knockout mouse has been a useful model of human citrin deficiency. One of the most prominent findings has been markedly increased hepatic glycerol 3-phosphate (G3P) following oral administration of a sucrose solution. We aimed to investigate whether this change is detectable outside of the liver, and to explore the mechanism underlying the increased hepatic G3P in these mice. We measured G3P and its metabolite glycerol in plasma and urine of the mice under various conditions. Glycerol synthesis from fructose was also studied using the liver perfusion system. The citrin/mGPD double-knockout mice showed increased urine G3P and glycerol under normal, fed conditions. We also found increased plasma glycerol under fasted conditions, while oral administration of different carbohydrates or ethanol led to substantially increased plasma glycerol. Fructose infusion to the perfused liver of the double-knockout mice augmented hepatic glycerol synthesis, and was accompanied by a concomitant increase in the lactate/pyruvate (L/P) ratio. Co-infusion of either pyruvate or phenazine methosulfate, a cytosolic oxidant, with fructose corrected the high L/P ratio, leading to reduced glycerol synthesis. Overall, these findings suggest that hepatic glycerol synthesis is cytosolic NADH/NAD(+) ratio-dependent and reveal a likely regulatory mechanism for hepatic glycerol synthesis following a high carbohydrate load in citrin-deficient patients. Therefore, urine G3P and glycerol may represent potential diagnostic markers for human citrin deficiency.

Angle between the common and internal carotid arteries detected by ultrasound is related to intima-media thickness among those with atherosclerotic disease.

OBJECTIVES: Although carotid artery structural variations have been detected by ultrasound, their clinical significance is not fully understood. The objective of this study was to determine whether the angle between the common carotid artery (CCA) and the internal carotid artery (ICA), designated angle α, an ultrasound-detectable carotid artery structural variation, is related to carotid artery intima-media thickness (IMT), a surrogate marker for carotid atherosclerosis. METHODS: As a cross-sectional study, we measured angle α in routine carotid artery ultrasounds from 176 subjects (130 men) with atherosclerotic disease/risk factors that attended Kouseiren Hospital in Kagoshima City, Japan between August 2007 and April 2009. We evaluated the correlation between the angle α and CCA- or ICA-IMT. RESULTS: Angle α was weakly correlated with age but significantly correlated with ICA-IMT. The correlation was stronger in subjects with an ICA-IMT ≥ 0.5 mm than in those with an ICA-IMT < 0.5 mm (Right side r = 0.475 vs. 0.246, Left side r = 0.498 vs. 0.301, respectively). Upon multivariate logistic regression analysis, angle α and serum low-density lipoprotein cholesterol were independent explanatory variables for ICA-IMT. CONCLUSION: Angle α is related to ICA-IMT in subjects with atherosclerotic disease or risk factors in this study.