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Introduction: Cerebral white matter hyperintensities (WMHs) are commonly found in the aging brain and have been implicated in the initiation and severity of many central nervous system diseases. Furthermore, an increased WMH volume indicates reduced brain health in older adults. This study investigated the association between WMH volume and physical activity in older adults with depressive symptoms (DS) and mild memory impairment (MMI). Factors associated with the WMH volume were also investigated. Methods: A total of 57 individuals aged over 65 years with DS and MMI were included in this study. The participants underwent magnetic resonance imaging to quantify WMH volumes. After WMH volume was accumulated, normalized to the total intracranial volume (TIV), the percentage of WMH volume was calculated. In addition, all participants wore a triaxial accelerometer for 2 weeks, and the average daily physical activity and number of steps were measured. The levels of blood biomarkers including cortisol, interleukin-6 (IL-6), brain-derived insulin-like growth factor-1, and brainderived neurotrophic factor were measured. Motor and cognitive functions were also assessed. Results: Faster maximum walking speed and longer time spent engaged in moderate physical activity were associated with a smaller percent of WMH volume, whereas higher serum IL-6 levels were associated with a larger percent of WMH volume. The number of steps per day, time spent engaged in low levels of physical activity, cognitive function, and all other measured biomarkers were not significantly associated with percent of WMH volume. Discussion: Higher blood inflammatory cytokine levels, shorter duration of moderate physical activity, and lower maximum walking speed were associated with a higher percent of WMH volume. Our results provide useful information for maintaining brain health in older adults at a high risk of developing dementia and may contribute to the development of preventive medicine for brain health. [ABSTRACT FROM AUTHOR]

Angelica keiskei is a perennial plant, belonging to the Apiaceae family and originating from Japan. This plant has been reported to act as a diuretic, analeptic, antidiabetic, hypertensive, tumor, galactagogue, and laxative. The mechanism of action of A. keiskei is not known, but previous studies have suggested that it may act as an antioxidant. In this work, we used Drosophila melanogaster to evaluate the impact of A. keiskei on lifespan and healthspan and its potential anti-aging mechanism by conducting multiple assays on three fly strains: w1118, chico, and JIV. We observed that the extract extended lifespan and improved healthspan in a sex- and strain-dependent manner. A. keiskei extended lifespan and improved reproductive fitness in female flies and either had no effect or decreased survival and physical performance in males. The extract protected against the superoxide generator paraquat in both sexes. These sex-specific effects suggest that A. keiskei may act through age-specific pathways such as the insulin and insulin-like growth factor signaling (IIS) pathways. Upon examination, we found that the increased survival of A. keiskei-fed females was dependent on the presence of the insulin receptor substrate chico, supporting the role of IIS in the action of A. keiskei. [ABSTRACT FROM AUTHOR]

Background: Thyroid stimulating hormone (TSH) receptor and local infiltrate lymphocytes have been considered as major pathological factors for developing thyroid-related ophthalmopathy. Overexpression of insulin-like growth factor-I (IGF-I) receptor has emerged as a promising therapeutic target for refractory patients. However, the relationship between activation of growth hormone (GH)/IGF-I receptor signaling and development or exacerbation of thyroid ophthalmopathy has not been elucidated. Herein we describe a case that provides further clarification into the association between thyroid-related ophthalmopathy and GH/IGF-I receptor signaling. Case presentation: A 62-year-old Japanese female diagnosed with thyroid-related ophthalmopathy was admitted to Kurume University Hospital. She had received daily administration of GH subcutaneously for severe GH deficiency; however, serum IGF-I levels were greater than + 2 standard deviation based on her age and sex. She exhibited mild thyrotoxicosis and elevation in levels of TSH-stimulating antibody. Discontinuation of GH administration attenuated the clinical activity scores of her thyroid-related ophthalmopathy. Additionally, concomitant use of glucocorticoid and radiation therapies resulted in further improvement of thyroid-related ophthalmopathy. The glucocorticoid administration was reduced sequentially, followed by successful termination. Thereafter, the patient did not undergo recurrence of thyroid-related ophthalmopathy and maintained serum IGF-I levels within normal physiological levels. Conclusions: We describe here a case in which development of thyroid-related ophthalmopathy occurred upon initiation of GH administration. GH/IGF-I signaling was highlighted as a risk factor of developing thyroid-related ophthalmopathy. Additionally, aberrant TSH receptor expression was suggested to be a primary pathophysiological mechanism within the development of thyroid-related ophthalmopathy. Physicians should be aware of the risks incurred via GH administration, especially for patients of advanced age, for induction of thyroid-related ophthalmopathy. [ABSTRACT FROM AUTHOR]

Background: Insulin-like growth factor-1 (IGF-1) acts on glucose and protein metabolism and human growth and also influences blood pressure and renal function. This study investigated whether the single-nucleotide polymorphism of IGF-1, rs35767, plays a role in metabolic syndrome indicators, including blood pressure, glucose metabolism, uric acid levels, and renal function.Methods: In this retrospective longitudinal cohort study, blood samples from 1506 Japanese individuals were collected and used for genotyping for variant rs35767: T > C in the IGF-1 upstream promoter. Data were analyzed to identify associations between IGF-1 genotypes and patient biochemical parameters, including the components of metabolic syndrome and the long-term change in renal function.Results: The cohort rs35767 genotypes included 650 CC carriers (43.2%), 687 TC carriers (45.6%), and 169 TT carriers (11.2%). Multiple regression analysis revealed no association between IGF-1 genotype and blood pressure, glycated hemoglobin level, and serum uric acid level. However, in females, blood pressure was negatively correlated with the TT genotype. Longitudinal observation revealed that the decline in eGFR over 10 years was greater in TT (- 18.51 ± 1.04 mL/min/1.73m2) than in CC carriers (- 16.38 ± 0.52 mL/min/1.73m2; P < 0.05).Conclusion: The present study suggests that renal function declines faster in individuals with the TT genotype at the IGF-1 rs35767 locus than in those with the CC genotype, suggesting that the TT genotype is associated with the long-term chronological decline in renal function. [ABSTRACT FROM AUTHOR]

Highlights • Circulating IGFBP-1b is a negative index of growth for juvenile chum salmon. • Growth status of juveniles in wild was assessed using IGFBP-1b and IGF-I. • The use of multiple indices may stabilize growth evaluation in the field. Abstract This study aimed to utilize circulating insulin-like growth factor binding protein (IGFBP)-1b as a negative index of growth to evaluate the growth status of juvenile chum salmon (Oncorhynchus keta) in the ocean. First, rearing experiments using PIT-tagged juveniles were conducted to examine the relationship of circulating IGFBP-1b with growth rate of the fish in May and in June. The serum IGFBP-1b level negatively correlated with fish growth rate in both months, suggesting its utility as a negative index of growth. Next, the growth status of out-migrating juveniles in northeastern Hokkaido, Japan, was monitored for 3 years using the growth indices. Serum levels of IGF-I, a positive index of growth, in fish collected from the nearshore zone were low in May and high in June of all years. Levels of serum IGFBP-1b showed a trend opposite to that of serum IGF-I. However, the IGF-I/IGFBP-1b molar ratios well reflected the seasonal and regional trends. These findings suggest that the juveniles in June left the nearshore area under better growth conditions. The present study also suggests that the use of multiple growth indices would improve the sensitivity and accuracy to evaluate the current growth status of out-migrating juvenile chum salmon. [ABSTRACT FROM AUTHOR]

Aims: Previous studies have suggested that insulin‐like growth factor‐I (IGF‐I) deficiency may lead to cognitive deficits in neurodegenerative diseases such as Alzheimer's disease. The present study aimed to investigate the possible relationship between cognitive function and concentration of IGF‐I or amyloid beta protein (Aβ) in serum in Alzheimer's patients. Methods: A total of 81 Japanese patients were enrolled in this study. Concentrations of IGF‐I, Aβ42, and Aβ40 in serum were measured. Two neuropsychological tests, Mini‐Mental State Examination and Hasegawa's Dementia Scale‐Revised (HDS‐R), were also performed. Linear correlations among the age, serum IGF‐I, serum Aβ42 or Aβ40, Aβ42/Aβ40 ratio, Mini‐Mental State Examination or HDS‐R total score, and the scores for six HDS‐R subscales were analyzed by regression analysis. Results: IGF‐I showed a significant negative correlation with age (β = −0.357, P = 0.002) and a positive correlation with Aβ42/Aβ40 ratio (β = 0.318, P = 0.007). Serum IGF‐I and both the Mini‐Mental State Examination and the HDS‐R total score also correlated (β = 0.505, β = 0.524, P < 0.01). Among the HDS‐R subscales, ‘Recall’ (ρ = 0.379, P < 0.01), ‘Verbal fluency’ (ρ = 0.360, P < 0.01), and ‘Attention and calculation’ (ρ = 0.389, P < 0.01) showed significant positive correlations with serum IGF‐I. Conclusion: The results, specifically that lower serum IGF‐I was associated with cognitive impairment, suggest that metabolism of IGF‐I may be involved in the pathogenesis of cognitive deficits in Alzheimer's disease. [ABSTRACT FROM AUTHOR]

GH plays a significant role in the lipid metabolism. In this study, we focused on the JAK2 - signal transducer and activator of the transcription 5 (STAT5) pathway, which transmit the signals from the GH receptor, and selected the STAT5A/B gene as a candidate for the regulation of lipid metabolism in GH deficiency (GHD). The study population comprised 83 children with idiopathic GHD. The serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and the non-HDL cholesterol (non-HDL-C) levels were monitored before and at 3, 6, 9 and 12 months after starting GH treatment. The height, weight, body mass index, and serum insulin-like growth factor-I (IGF-I) level were also measured before and 12 months after starting the GH treatment. For the genetic analysis of the STAT5A/B gene, five tag SNPs were selected using the tag SNP picker programme on the homepage of the HapMap project. The evaluation of promoter activity of the −44816A/G SNP in the STAT5B gene was performed by a luciferase assay in vitro. The TC and non-HDL-C levels were gradually decreased during the GH treatment. Five tag SNPs (rs4029774, rs6503691, rs9900213, rs16967637 and rs2272087) were picked up for the STAT5A/B gene, and the genetic study demonstrated that the paediatric GHD patients who were heterozygotes or homozygotes of minor alleles of the analysed SNPs in the same block of the STAT5B gene showed significantly higher serum TC or non-HDL-C levels both before and after GH treatment for 12 months. Most of the SNPs also demonstrated significant differences among genotypes in the decreases in serum TC or non-HDL-C levels during the 12 months of GH treatment. A luciferase assay showed that the −44816A/G SNP (rs4029774) in the STAT5B gene functionally affected the expression level in vitro. These results indicate that STAT5B may therefore play a role in regulating the cholesterol metabolism in children with GHD. [ABSTRACT FROM AUTHOR]

Abstract: Treatment with donepezil (maximum dose, 10mg/day) was recently approved in Japan for severe Alzheimer''s disease (AD). We examined the usefulness of serum insulin-like growth factor-I (IGF-I) level as a biomarker for predicting responders to 10mg/day-donepezil treatment among mild-to-moderate AD patients. The study population consisted of 23 mild-to-moderate AD patients, who were non-responders to 5mg/day-donepezil treatment. AD patients were divided into responders and non-responders based on changes in mini-mental state examination (MMSE) scores before and 12weeks after increasing donepezil dose from 5 to 10mg/day. Before increasing donepezil dose, based on serum IGF-I levels and MMSE scores positively correlated with each other, AD patients were classified into three groups. Group A (n =6) had IGF-I≤99ng/mL and MMSE≤18, group B (n =9) had IGF-I≤99ng/mL and MMSE>18, and group C (n =8) had IGF-I>99ng/mL and MMSE>18. Serum IGF-I levels were significantly lower in groups A and B than group C. After 10mg/day-donepezil treatment, the mean MMSE improved significantly only in group A. The prevalence of responders to the treatment was markedly greater in group A than in groups B and C. These results suggested that decreased serum IGF-I level combined with low MMSE score may be a useful biomarker for predicting responders to 10mg/day-donepezil treatment in mild-to-moderate AD patients exhibiting a poor response to 5mg/day-donepezil treatment. [Copyright &y& Elsevier]

Abstract: Background: We investigated the association between serum levels of IGF-I, IGF-II, and IGFBP-3 and the subsequent risk of cancer mortality. Methods: Our case–control study examined samples from 914 cancer deaths and their 2739 matched controls within the Japan Collaborative Cohort Study. Blood samples were obtained at the baseline and stored at −80°C until analysis for IGF-I, IGF-II, and IGFBP-3 levels. The conditional logistic model was used to estimate odds ratios (ORs) for cancer mortality associated with these serum levels. Results: The adjusted ORs for IGF-I quartiles ranged from 0.81 to 0.96 but were not significant. The adjusted ORs and 95% confidence interval (CI) for the second, third, and fourth IGF-II quartiles were 0.64 (95% CI: 0.52–0.79), 0.71 (95% CI: 0.58–0.88), and 0.73 (95% CI: 0.59–0.91), respectively, while those for the respective IGFBP-3 quartiles were 0.77 (95% CI: 0.63–0.96), 0.75 (95% CI: 0.60–0.94), and 0.71 (95% CI: 0.56–0.90). In the model of IGF-I, and IGF-II additionally adjusted for IGFBP-3, the associations of high IGFs levels were similar as observed in the above models, while the association of IGFBP-3 shifted into non-significance after adjusting for IGF-II. Conclusion: An increased level of IGF-II was significantly associated with decreased risk of cancer mortality, whereas the association between IGF-I and all cancer mortality was not significant. The inverse association of IGFBP-3 level with all cancer mortality was affected when adjusting for IGF-II levels, shifting from significant to non-significant. Confirmation of these results from further cohort studies may aid in identifying the potential association between these molecules and the risk of cancer among the general Japanese population. [Copyright &y& Elsevier]

Abstract: Insulin-like growth factor-I (IGF-I) has been proposed as the link between diet and breast cancer risk. Due to their estrogen-like structure, soy isoflavones may affect IGF-I levels in a similar way as exogenous estrogens. In a cross-sectional design, we compared IGF-I levels between women with high and low soy intake. The analysis included 611 pre- and postmenopausal women: Japanese in Japan and Japanese and Caucasians in Hawaii. The subjects had participated in a previous study, were never diagnosed with breast cancer, provided a screening mammogram and a blood sample, and completed validated food-frequency questionnaires. The same laboratory analyzed all serum samples for IGF-I and IGF binding protein (IGFBP)-3 by enzyme-linked immunosorbent assay. We estimated covariate-adjusted mean IGF-I and IGFBP-3 levels by tofu intake. The respective mean IGF-I levels were 213, 257, and 255 ng/ml for Japanese in Japan, Japanese in Hawaii, and Caucasians in Hawaii. Tofu intake was higher in Japan than among Japanese and Caucasians in Hawaii (11.0 vs. 9.4 and 4.9 g/1,000 kcal). Mean IGF-I levels were 11% lower among women in the highest tofu intake category compared with the lowest, but the difference in IGF-I levels between the highest and lowest tofu category was only significant among women in Japan. Inclusion of total energy, total protein, meat, and dairy intake did not materially alter the association between tofu consumption and IGF-I levels. These findings suggest that a diet rich in soy foods and low in meats may be related to lower IGF-I levels, but it is unclear whether soy or other characteristics of diet and lifestyle are responsible for this association. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the effects of arginine on nutrition, growth and urea cycle function in boys with late-onset ornithine transcarbamylase deficiency (OTCD). Seven Japanese boys with late-onset OTCD enrolled in this study resumed arginine treatment after the cessation of this therapy for a few years. Clinical presentations such as vomiting and unconsciousness, plasma amino acids and urinary orotate excretion were followed chronologically to evaluate urea cycle function and protein synthesis with and without this therapy. In addition to height and body weight, blood levels of proteins, lipids, growth hormone (GH), insulin-like growth factor-I (IGF-I) and IGF-binding protein -3 (IGFBP-3) were monitored.Results: The frequency of hyperammonemic attacks and urinary orotate excretion decreased significantly following the resumption of arginine treatment. Despite showing no marked change in body weight, height increased gradually. Extremely low plasma arginine increased to normal levels, while plasma glutamine and alanine levels decreased considerably. Except for a slight increase in high-density lipoprotein cholesterol level, blood levels of markers for nutrition did not change. In contrast, low serum IGF-I and IGFBP-3 levels increased to age-matched control levels, and normal urinary GH secretion became greater than the level observed in the controls.Conclusion: Arginine treatment is able to reduces attacks of hyperammonemia in boys with late-onset OTCD and to increase their growth. [ABSTRACT FROM AUTHOR]

To study the mechanism of faster growth of the sculpin Cottus kazika in seawater (SW) than in fresh water (FW), we transferred 120-day-old juveniles from FW to SW, 1/3 SW or FW, and survival, growth and levels of transcripts of growth hormone (GH) gene in the pituitary and insulin-like growth factor I (IGF-I) gene in the liver were examined 20 and 40 days after transfer. The survival rates of fish reared in SW and 1/3 SW were higher than the FW controls. The growth was fastest in SW and slowest in the controls. IGF-I gene transcripts increased in SW-reared fish 40 days after transfer compared with the controls, while GH gene transcripts did not. Juveniles of 1 year of age were transferred from FW to SW or 1/3 SW, and GH and IGF-I gene transcripts were compared after 48 h. In this short-term experiment, the level of GH gene transcripts was higher in fish reared in SW and 1/3 SW, while no difference was found in the IGF-I gene transcripts. Thus, the GH gene transcripts increased only transiently after SW transfer but the IGF-I gene transcripts increased gradually for 40 days, suggesting that the long-term increase in IGF-I gene expression is involved in the enhanced growth in SW and GH may play an initiation role for growth enhancement. [ABSTRACT FROM AUTHOR]

High levels of plasma insulin-like growth factor I (IGF-I) and low levels of insulin-like growth factor binding protein 3 (IGFBP-3) have been related to increased risk of several cancers. Little is known about the behavioral determinants of these biologic markers. The authors examined the relation of anthropometric and behavioral factors to plasma concentrations of IGF-I and IGFBP-3 in a cross-sectional study of 616 Japanese men aged 45–55 years in 1995–1996. In univariate analyses, body mass index was strongly, positively associated with both IGF-I and IGFBP-3. The waist/hip ratio was also linearly related to IGF-I and IGFBP-3 up to the third quartile level. Height was weakly, positively associated with IGF-I and IGFBP-3. Smoking was inversely associated with IGF-I and IGFBP-3. Alcohol use was associated inversely with IGF-I and positively with IGFBP-3. Neither IGF-I nor IGFBP-3 was related to physical activity. Results of the multivariate analysis were essentially the same as those of the univariate analyses. The findings regarding body mass index are in contrast to those of previous studies showing null or inverse associations, and they suggest that the relation of body mass index to IGF-I or IGFBP-3 may vary among populations. The study also indicates that smoking and alcohol use might affect plasma IGF-I and IGFBP-3. [ABSTRACT FROM PUBLISHER]

A cDNA encoding the porcine type 1 insulin-like growth factor receptor (IGF1R) was amplified by reverse transcriptase-polymerase chain reaction (RT-PCR). The sequence of a 4.2-kb product was determined and had an open reading frame, encoding 1367 amino acids with 98.1 and 95.2% sequence similarity to the human and rat IGF1R, respectively. In the comparison of RT-PCR derived IGF1R sequences from 12 unrelated pigs, 12 silent sequence variants were found. [ABSTRACT FROM AUTHOR]

The article discusses the highlights of one of the symposiums of the 111th Annual Meeting of the Japanese Association for Anatomists (JAA) held on March 20, 2006 at the Sagamihara Campus of Kitasato University in Japan. The symposium aimed to introduce olfactory research mainly done by the members of the JAA. The first talk reviewed molecular mechanisms related to regulatory mechanisms of apoptosis of olfactory receptor cells (ORC). Another talk presented data related to the regulatory roles of insulin-like growth factor (IGF) in apoptosis of ORC.

Sumo is a traditional Japanese full-contact wrestling sport. Among sumo wrestlers, Ikezuki Geitazaemon (1827-1850) was one of the most famous wrestlers due to his large body size. Here, we hypothesize that the legendary Japanese sumo wrestler could have had gigantism or acromegaly, which are disorders caused by the hypersecretion of growth hormone (GH). GH-secreting pituitary adenoma leads to the hypersecretion of GH and insulin-like growth factor-1 (IGF-1). If GH-secreting pituitary adenoma develops during childhood/puberty, it can cause gigantism. Adenomas also occur in over 95% of patients with acromegaly. Based on his substantial height (227 cm), Geitazaemon may have had gigantism, or acromegaly considering his characteristics of mandibular prognathism, enlarged fingertips, and heel pad thickness, as shown in woodblock prints (ukiyo-e). He would thus be the first recorded patient with gigantism or acromegaly in premodern Japan. [ABSTRACT FROM AUTHOR]

We aimed to determine the effects of nutritional status on concentrations of somatotropic axis hormones (growth hormone (GH) and insulin-like growth factor 1 (IGF-1)), insulin and metabolites (glucose, total protein and nonesterified fatty acids (NEFA)) in the plasma and colostrum in late antepartum cows. Eight pregnant Japanese Black cows were randomly assigned to two experimental groups ( n = 4 per group). Control cows (CON) received 100% of their nutritional requirements until parturition, whereas restricted group cows (RES) received 60% of their nutritional requirements. Blood samples were taken during the antepartum period, and blood and colostrum samples were collected on days 0, 1, and 3 after calving. Compared to the CON group, the RES group had higher concentrations of GH and NEFA in plasma, but significantly lower concentrations of glucose and insulin in plasma. The concentrations of GH in plasma after calving were significantly higher, but total plasma protein was significantly lower in RES than in CON cows. Compared to the CON group, the RES group had significantly higher concentrations of GH in colostrum, but significantly lower total concentrations of protein in colostrum. Concentrations of IGF-1 were not different between the two groups. These findings suggest that maternal nutritional status during late gestation influences concentrations of GH and total protein in the blood and colostrum of Japanese Black cows. [ABSTRACT FROM AUTHOR]