Plasma IGF-I Levels Research Articles

Relationships among maternal backfat depth, plasma adipokines and the birthweight of piglets

Adipose tissue produces hormones, such as leptin and adiponectin, that are key factors in energy metabolism. The aim of this study was to assess the endocrine role of the adipose tissue in controlling intrauterine growth, so we evaluated the relationships among maternal adiposity, leptin and adiponectin-pregnancy trends and foetal growth in 48 Large White x Landrace crossbreed sows. Two groups of sows were designated based on backfat (BF) depth at the end of the lactation phase: a Low Fat group (LF, 11.60 mm; n = 24) and a High Fat group (HF, 18.20 mm; n = 24). During the subsequent pregnancies, the same level of feed was provided to both groups. The BF values of the sows were recorded, and blood samples were collected to assess the concentrations of leptin and adiponectin at mating and during gestation. The weights and temperatures of piglets were recorded at farrowing and after 24 h, and their body mass index and ponderal index values were calculated at farrowing. Before the piglets suckled colostrum, blood samples were collected, and the leptin, adiponectin and IGF-1 plasma levels were analysed. The observed differences in backfat depth between the LF and HF groups at mating persisted during pregnancy, and a decrease in adiponectin and an increase in leptin plasma levels were observed throughout gestation in both groups. Plasma adiponectin was lower in the HF group than in the LF group, but plasma leptin did not differ significantly. Compared to HF sows, LF sows gave birth to lighter piglets (P = 0.014). In addition, the weights of 27% of the piglets in the LF group and 14% in the HF group fell within the first 25th percentile (weight ≤ 1 kg). A positive correlation between offspring weight and maternal adiposity at mating (r = 0.149; P = 0.020) and a negative correlation between offspring weight and adiponectin-leptin ratio at mating (r = −0.198; P = 0.022) were observed. The morphometric parameters (body mass index, ponderal index) and thermoregulatory abilities of the piglets were unaffected by maternal adiposity. In terms of haematology, differences were found in the IGF-1 level, which was lower in piglets born from LF than HF sows (P < 0.001). The knowledge gained from this study suggested that differences in maternal adiposity, which were due to individual variability and not feeding strategies, influence the plasma concentration of adipokines, thus affecting offspring weight.

Abstract WP196: MicroRNA and IGF-1 as Predictive Biomarkers for Stroke Outcomes

Background: Although several studies focus on biomarkers for stroke diagnosis, few studies have identified biomarkers that predict stroke recovery. In our preclinical studies, we identified that the peptide hormone insulin-like growth factor (IGF-1) and specific small non-coding RNA (miRNA) are inversely corelated with stroke severity as measured by infarct volume. The objective of this study is to assess the potential of miRNA and IGF-1 to serve as predictors of stroke outcomes in patients as assessed by NIHSS at 90 days after stroke. Methods: Male and female patients ages (19-91) years were enrolled at the emergency department of a local hospital. NIHSS scores were obtained at presentation, discharge from the hospital, and 90-day follow-up. Scores were binned into mild (1-4), moderate (5-20) and severe (≥ 21). Prospective blood specimens were collected from the participant within 24 hours of presentation to the emergency department and at 90 + 7 days after initial presentation. Plasma IGF-1 levels were estimated using the Quantikine ELISA for human IGF-1 and and miR-363 expression was determined by qRT-PCR using hsa-miR-363-3p primers. IGF-1 and mir363-3p levels from blood samples collected within 24h of presentation were correlated with binned NIHSS-90 days, separately for males and females. Results: In males, there was no correlation between the degree of stroke severity at 90 days with either IGF-1 levels or mir363-3p. In females, there was significant inverse correlation between IGF-1 levels and NIHSS-90d scores (r=-0.467; p&lt;0.05), indicating that higher IGF-1 levels were predictive of better stroke recovery. However, miR-363 levels did not correlate with the 90d NIHSS. Conclusion: These pilot data suggest that IGF-1 is a strong predictor of stroke severity in females and has the potential to serve as a surrogate measure for stroke recovery. Supported by TAMUOVPR and TBSI seed grant to FS

Plasma insulin-like growth factor-1 is unrelated to female reproductive development in a wild population of Dolly Varden charr Salvelinus malma (Walbaum, 1792)

Insulin-like growth factors (IGFs) are endocrine agents that signal growth in fishes. Because of the interplay between growth and reproduction, endocrine control of the growth axis is thought to have a connection to the reproductive axis. Seasonal patterns and relationships between IGF-1, fish condition, and gonadal development were investigated in a wild population of female Dolly Varden charr Salvelinus malma (Walbaum, 1792) during the summer growing season prior to spawning. Fish were sampled from Florence Lake, Alaska on five sequential sampling trips during April–October 2006. Body and gonad morphometric measurements, and blood plasma samples were obtained for IGF-I quantification. IGF-I increased during summer with fish condition. The gonadosomatic index indicated a pattern of advancing reproductive development in one cohort of fish by August, which indicated impending spawning compared to an immature (non-reproductive) cohort. However, plasma IGF-I levels were not predictive of the sexually maturing cohort. We conclude that IGF-I is not a useful endocrine marker of advancing reproductive state in female Dolly Varden charr but does relate to fish condition during the summer growth period.

Somatotropic Axis Regulation Unravels the Differential Effects of Nutritional and Environmental Factors in Growth Performance of Marine Farmed Fishes.

The Gh/Prl/Sl family has evolved differentially through evolution, resulting in varying relationships between the somatotropic axis and growth rates within and across fish species. This is due to a wide range of endogenous and exogenous factors that make this association variable throughout season and life cycle, and the present minireview aims to better define the nutritional and environmental regulation of the endocrine growth cascade over precisely defined groups of fishes, focusing on Mediterranean farmed fishes. As a result, circulating Gh and Igf-i are revitalized as reliable growth markers, with a close association with growth rates of gilthead sea bream juveniles with deficiency signs in both macro- or micro-nutrients. This, together with other regulated responses, promotes the use of Gh and Igf-i as key performance indicators of growth, aerobic scope, and nutritional condition in gilthead sea bream. Moreover, the sirtuin-energy sensors might modulate the growth-promoting action of somatotropic axis. In this scenario, transcripts of igf-i and gh receptors mirror changes in plasma Gh and Igf-i levels, with the ghr-i/ghr-ii expression ratio mostly unaltered over season. However, this ratio is nutritionally regulated, and enriched plant-based diets or diets with specific nutrient deficiencies downregulate hepatic ghr-i, decreasing the ghr-i/ghr-ii ratio. The same trend, due to a ghr-ii increase, is found in skeletal muscle, whereas impaired growth during overwintering is related to increase in the ghr-i/ghr-ii and igf-ii/igf-i ratios in liver and skeletal muscle, respectively. Overall, expression of insulin receptors and igf receptors is less regulated, though the expression quotient is especially high in the liver and muscle of sea bream. Nutritional and environmental regulation of the full Igf binding protein 1–6 repertoire remains to be understood. However, tissue-specific expression profiling highlights an enhanced and nutritionally regulated expression of the igfbp-1/-2/-4 clade in liver, whereas the igfbp-3/-5/-6 clade is overexpressed and regulated in skeletal muscle. The somatotropic axis is, therefore, highly informative of a wide-range of growth-disturbing and stressful stimuli, and multivariate analysis supports its use as a reliable toolset for the assessment of growth potentiality and nutrient deficiencies and requirements, especially in combination with selected panels of other nutritionally regulated metabolic biomarkers.

Effects of dietary carbohydrate levels on growth, glucose tolerance, glucose homeostasis and GLUT4 gene expression inTilapia nilotica

In this paper, the glucose tolerance tests (GTT) were performed to evaluate the effects of three dietary carbohydrate levels on growth, plasma glucose, hormones (insulin and IGF-I), glucose homeostasis and GLUT4 gene expression of Tilapia nilotica. Juvenile tilapia (av. wt.10 g) were randomly distributed into three groups with three replicates and fed for 8 weeks with three dietary carbohydrate levels: 40% (CH), 30% (CM) and 20% (CL). After 8 weeks of feeding trial, fish were injected with glucose (30 mg/100 g body weight) for GTT. The growth performance results showed the survival rate in the CH group was significantly lower than the other two groups (p < 0.05). The GTT results showed that the plasma glucose level positively correlates with the diets’ carbohydrate level initially, peaked at 1 hr and declined thereafter. The plasma IGF-1 levels were positively correlated with diets’ carbohydrate levels; first the levels increase and then decrease after injection in all the three groups. There was a direct relationship between the carbohydrate levels and the activities of liver pyruvate kinase (PK) and glucokinase (GK) enzymes. Muscle GLUT4 expression in groups changed slightly in 0–3 hr and then increased sharply during 6–12 hr. Results of this study indicated that the moderate dietary carbohydrate level may improve the glucose tolerance of T. nilotica. The carbohydrate levels can affect plasma glucose, IGF-1 and GLUT4 expression in T. nilotica. In addition, the IGF-1 may play a more important role on the glucose metabolism than insulin. The delayed gene transcription of GLUT4 may be one of the reasons for glucose intolerance in T. nilotica.

Association of circular Klotho and insulin-like growth factor 1 with cardiac hypertrophy indexes in athlete and non-athlete women following acute and chronic exercise

Owing to the role of insulin-like growth factor 1 (IGF-I) in cardiac hypertrophy and the ability of Klotho in inhibiting the IGF-I action, we investigated effects of exercise on plasma Klotho and IGF-I and their association with cardiac hypertrophy. In this study, 10 non-athlete and 10 athlete women underwent a Bruce test (acute exercise) and 12-weeks water aerobics training (chronic exercise). Electrocardiographic parameters, plasma IGF-I and Klotho levels were measured in different time courses. The exercise training could significantly increase left ventricular end-diastolic diameter index (LVEDDI) in the non-athletes. Plasma levels of IGF-I significantly increased following acute and chronic exercises. The Klotho levels at the baseline were higher in athletes than non-athletes and its levels significantly increased immediately after acute exercise in both groups. The Klotho levels significantly decreased in non-athletes 24 h after chronic exercise, but its level was still higher than the baseline in the athletes. We found positive and negative correlations between cardiac hypertrophy indexes (LVEDDI and left ventricular mass index) with respectively IGF-I and Klotho. In conclusion, we found a stimulatory effect of acute and chronic exercises on plasma IGF-I and Klotho and association of IGF-I with exercise-induced cardiac hypertrophy. Moreover, Klotho could act as a negative regulator for exercise-induced cardiac hypertrophy.

Ghrelin and Its Receptors in Gilthead Sea Bream: Nutritional Regulation.

Ghrelin is involved in the regulation of growth in vertebrates through controlling different functions, such as feed intake, metabolism, intestinal activity or growth hormone (Gh) secretion. The aim of this work was to identify the sequences of preproghrelin and Ghrelin receptors (ghsrs), and to study their responses to different nutritional conditions in gilthead sea bream (Sparus aurata) juveniles. The structure and phylogeny of S. aurata preproghrelin was analyzed, and a tissue screening was performed. The effects of 21 days of fasting and 2, 5, 24 h, and 7 days of refeeding on plasma levels of Ghrelin, Gh and Igf-1, and the gene expression of preproghrelin, ghsrs and members of the Gh/Igf-1 system were determined in key tissues. preproghrelin and the receptors are well conserved, being expressed mainly in stomach, and in the pituitary and brain, respectively. Twenty-one days of fasting resulted in a decrease in growth while Ghrelin plasma levels were elevated to decrease at 5 h post-prandial when pituitary ghsrs expression was minimum. Gh in plasma increased during fasting and slowly felt upon refeeding, while plasma Igf-1 showed an inverse profile. Pituitary gh expression augmented during fasting reaching maximum levels at 1 day post-feeding while liver igf-1 expression and that of its splice variants decreased to lowest levels. Liver Gh receptors expression was down-regulated during fasting and recovered after refeeding. This study demonstrates the important role of Ghrelin during fasting, its acute down-regulation in the post-prandial stage and its interaction with pituitary Ghsrs and Gh/Igf-1 axis.

In vivo effects of 17α-ethinylestradiol, 17β-estradiol and 4-nonylphenol on insulin-like growth-factor binding proteins (igfbps) in Atlantic salmon

Feminizing endocrine disrupting compounds (EDCs) affect the growth and development of teleost fishes. The major regulator of growth performance, the growth hormone (Gh)/insulin-like growth-factor (Igf) system, is sensitive to estrogenic compounds and mediates certain physiological and potentially behavioral consequences of EDC exposure. Igf binding proteins (Igfbps) are key modulators of Igf activity, but their alteration by EDCs has not been examined. We investigated two life-stages (fry and smolts) of Atlantic salmon (Salmo salar), and characterized how the Gh/Igf/Igfbp system responded to waterborne 17α-ethinylestradiol (EE2), 17β-estradiol (E2) and 4-nonylphenol (NP). Fry exposed to EE2 and NP for 21 days had increased hepatic vitellogenin (vtg) mRNA levels while hepatic estrogen receptor α (erα), gh receptor (ghr), igf1 and igf2 mRNA levels were decreased. NP-exposed fry had reduced body mass and total length compared to controls. EE2 and NP reduced hepatic igfbp1b1, -2a, -2b1, -4, -5b2 and -6b1, and stimulated igfbp5a. In smolts, hepatic vtg mRNA levels were induced following 4-day exposures to all three EDCs, while erα only responded to EE2 and E2. EDC exposures did not affect body mass or fork length; however, EE2 diminished plasma Gh and Igf1 levels in parallel with reductions in hepatic ghr and igf1. In smolts, EE2 and E2 diminished hepatic igfbp1b1, -4 and -6b1, and stimulated igfbp5a. There were no signs of compromised ionoregulation in smolts, as indicated by unchanged branchial ion pump/transporter mRNA levels. We conclude that hepatic igfbps respond (directly and/or indirectly) to environmental estrogens during two key life-stages of Atlantic salmon, and thus may modulate the growth and development of exposed individuals.

Lack of Brain Insulin Receptor Substrate-1 (IRS1) Causes Growth Retardation via Growth Hormone Releasing Hormone

Background and Purpose: We previously revealed that systemic Irs1 deficient mice showed growth retardation, indicating that Irs1 plays an important role in growth. Irs1 is main substrate of not only insulin receptor (IR) but also IGF-1 receptor (IGF-1R) tyrosine kinase. Recently, brain specific IGF-1 receptor knockout mice were reported to become growth impairment. We hypothesized that brain Irs1 may regulate growth via IGF-1. Methods: We generated NIrs1KO mice and analyzed growth related parameter and immunohistochemistry (IHC) study. Result: The body weight of NIrs1KO mice was significantly smaller than control mice. NIrs1KO mice also showed shorter body length and bone length. On the other hand food intake and gene expression of appetite-related neuropeptides (POMC, AgRP and NPY) were not different between two groups. We next confirmed that plasma IGF-1 and growth hormone (GH) levels of NIrs1KO mice were lower than control mice. Hypothalamic GHRH mRNA expression levels of NIrs1KO mice were also lower than those of control mice although hypothalamic somatostatin mRNA expression was not different between two groups. These data strongly suggest that lack of brain Irs1 causes growth retardation via GHRH. IHC study indicated that Irs1 colocalized with GHRH neuron in hypothalamus. We next investigated the IGF-1-induced proliferation in hypothalamic neural cells by using siIrs1. Downregulation of Irs1 significantly inhibited IGF-1-induced neural cell proliferation. Conclusion: Our results suggest that IGF-1-Irs1 pathway promotes the proliferation of GHRH neurons and regulate growth. Disclosure T. Hayashi: None. N. Kubota: None. T. Kubota: None. T. Kadowaki: Consultant; Self; Novo Nordisk A/S, AstraZeneca, Merck Sharp &amp; Dohme Corp.. Research Support; Self; Kissei Pharmaceutical Co., Ltd., Taisho Pharmaceutical Co., Ltd., Sanofi, Kyowa Hakko Kirin Co., Ltd., Novo Nordisk A/S, Astellas Pharma, Daiichi Sankyo Company, Limited, Takeda, Mitsubishi Tanabe Pharma Corporation, Ono Pharmaceutical Co., Ltd., Merck Sharp &amp; Dohme Corp., Nippon Boehringer Ingelheim Co. Ltd.. Speaker's Bureau; Self; Astellas Pharma, AstraZeneca, Merck Sharp &amp; Dohme Corp., Ono Pharmaceutical Co., Ltd., Takeda, Eli Lilly and Company, Nippon Boehringer Ingelheim Co. Ltd., Novo Nordisk A/S.

Identification and Pharmacological Profile of an Indane Based Series of Ghrelin Receptor Full Agonists.

Cachexia and muscle wasting are very common among patients suffering from cancer, chronic obstructive pulmonary disease, and other chronic diseases. Ghrelin stimulates growth hormone secretion via the ghrelin receptor, which subsequently leads to increase of IGF-1 plasma levels. The activation of the GH/IGF-1 axis leads to an increase of muscle mass and functional capacity. Ghrelin further acts on inflammation, appetite, and adipogenesis and for this reason was considered an important target to address catabolic conditions. We report the synthesis and properties of an indane based series of ghrelin receptor full agonists; they have been shown to generate a sustained increase of IGF-1 levels in dog and have been thoroughly investigated with respect to their functional activity.

Response of the insulin-like growth factor-1 (Igf1) system to nutritional status and growth rate variation in olive rockfish (Sebastes serranoides)

Growth performance in vertebrates is regulated by environmental factors including the quality and quantity of food, which influence growth via endocrine pathways such as the growth hormone (GH)/insulin-like growth factor somatotropic axis. In several teleost fishes, circulating concentrations of insulin-like growth factor-1 (Igf1) correlate positively with growth rate, and it has been proposed that plasma Igf1 levels may serve as an indicator of growth variation for fisheries and aquaculture applications. This study tested whether plasma Igf1 concentrations might serve as an indicator of somatic growth in olive rockfish (Sebastes serranoides), one species among dozens of rockfishes important to commercial and recreational fisheries in the Northern Pacific Ocean. Juvenile olive rockfish were reared under food ration treatments of 1% or 4% wet mass per d for 98 d to experimentally generate variation in growth. Juvenile rockfish in the 4% ration grew 60% more quickly in mass and 22% faster in length than fish in the 1% ration. Plasma Igf1 levels were elevated in rockfish under the 4% ration, and individual Igf1 levels correlated positively with growth rate, as well as with individual variation in hepatic igf1 mRNA levels. Transcripts encoding the Igf binding proteins (Igfbps) igfbp1a and igfbp1b were also at higher abundance in the liver of rockfish in the 1% ration treatment, while mRNAs for igfbp5a and igfbp5b were elevated in the skeletal muscle of 4% ration fish. These findings support the use of plasma Igf1 as a physiological index of growth rate variation in rockfish.

Co-expression Analysis of Sirtuins and Related Metabolic Biomarkers in Juveniles of Gilthead Sea Bream (Sparus aurata) With Differences in Growth Performance.

Sirtuins (SIRTs) represent a conserved protein family of deacetylases that act as master regulators of metabolism, but little is known about their roles in fish and livestock animals in general. The present study aimed to assess the value of SIRTs for the metabolic phenotyping of fish by assessing their co-expression with a wide-representation of markers of energy and lipid metabolism and intestinal function and health in two genetically different gilthead sea bream strains with differences in growth performance. Fish from the fast-growing strain exhibited higher feed intake, feed efficiency and plasma IGF-I levels, along with higher hepatosomatic index and lower mesenteric fat (lean phenotype). These observations suggest differences in tissue energy partitioning with an increased flux of fatty acids from adipose tissue toward the liver. The resulting increased risk of hepatic steatosis may be counteracted in the liver by reduced lipogenesis and enhanced triglyceride catabolism, in combination with a higher and more efficient oxidative metabolism in white skeletal muscle. These effects were supported by co-regulated changes in the expression profile of SIRTs (liver, sirt1; skeletal muscle, sirt2; adipose tissue, sirt5-6) and markers of oxidative metabolism (pgc1α, cpt1a, cs, nd2, cox1), mitochondrial respiration uncoupling (ucp3) and fatty acid and triglyceride metabolism (pparα, pparγ, elovl5, scd1a, lpl, atgl) that were specific to each strain and tissue. The anterior intestine of the fast-growing strain was better suited to cope with improved growth by increased expression of markers of nutrient absorption (fabp2), epithelial barrier integrity (cdh1, cdh17) and immunity (il1β, cd8b, lgals1, lgals8, sIgT, mIgT), which were correlated with low expression levels of sirt4 and markers of fatty acid oxidation (cpt1a). In the posterior intestine, the fast-growing strain showed a consistent up-regulation of sirt2, sirt3, sirt5 and sirt7 concurrently with increased expression levels of markers of cell proliferation (pcna), oxidative metabolism (nd2) and immunity (sIgT, mIgT). Together, these findings indicate that SIRTs may play different roles in the regulation of metabolism, inflammatory tone and growth in farmed fish, arising as powerful biomarkers for a reliable metabolic phenotyping of fish at the tissue-specific level.

Randomized, phase I/II study of gemcitabine plus IGF-1R antagonist (MK-0646) versus gemcitabine plus erlotinib with and without MK-0646 for advanced pancreatic adenocarcinoma

BackgroundBinding of insulin-like growth factor-I (IGF-1) to its receptor (IGF-1R) initiates downstream signals that activate PI3K/Akt/mTOR and MEK/Erk pathways, which stimulate cancer cell proliferation and induce drug resistance. Cross talk between IGF-1R and epidermal growth factor receptor (EGFR) mediates resistance to anti-EGFR agents. We studied safety, tolerability, and outcomes of MK-0646, IGF-1 monoclonal antibody, in combination with gemcitabine (G) ± erlotinib (E) in metastatic pancreatic cancer.MethodsOur study included a phase I dose escalation and phase II randomization and expansion cohorts. A 3 + 3 dose escalation protocol was used to determine MK-0646 maximum tolerable dose (MTD) in combination with G ± E standard doses. For phase II, patients were randomized to arm A (G + MK), arm B (G + MK + E), or arm C (G + E). Primary endpoint was progression-free survival (PFS). Secondary endpoints were overall survival (OS), disease control rate, toxicity, and correlation between OS and IGF-1 in patients treated with MK-0646.ResultsMK-0646 MTD was 10 mg/kg in combination with G and 5 mg/kg in combination with G + E. In randomization cohort, 15 patients were treated in each arm. Disease control rates were 50, 60, and 40% respectively. PFS was not different between the three arms. OS was significantly different between arm A (10.4 months) and C (5.7 months) (P = 0.02). However, addition of erlotinib in arm B yielded no OS benefit compared to arm A (P = 0.6). Plasma and tissue IGF-1 levels did not correlate with OS (P = 0.64, 0.87). Grade 3–4 toxicity during phase II cohorts were neutropenia (10/arm A, 14/arm B, 5/arm C), leukopenia (5/A, 5/B, 7/C), thrombocytopenia (8/A, 9/B, 2/C), hyponatremia (1/A, 3/B), and hyperglycemia (8/A, 1/B).ConclusionsMK-0646 was tolerable in combination with G and associated with improvement in OS but not PFS as compared with G + E. Tissue and serum IGF-1 did not correlate with clinical outcome.Trial registrationThis trial is registered in ClinicalTrial.gov under the Identifier NCT00769483 and registration date was October 9, 2008.

Selection for growth rate and body size have altered the expression profiles of somatotropic axis genes in chickens.

The growth hormone / insulin-like growth factor-1 (GH/IGF-1) pathway of the somatotropic axis is the major controller for growth rate and body size in vertebrates, but the effect of selection on the expression of GH/IGF-1 somatotropic axis genes and their association with body size and growth performance in farm animals is not fully understood. We analyzed a time series of expression profiles of GH/IGF-1 somatotropic axis genes in two chicken breeds, the Daweishan mini chickens and Wuding chickens, and the commercial Avian broilers hybrid exhibiting markedly different body sizes and growth rates. We found that growth rate and feed conversion efficiency in Daweishan mini chickens were significantly lower than those in Wuding chickens and Avian broilers. The Wuding and Daweishan mini chickens showed higher levels of plasma GH, pituitary GH mRNA but lower levels of hepatic growth hormone receptor (GHR) mRNA than in Avian broilers. Daweishan mini chickens showed significantly lower levels of plasma IGF-1, thigh muscle and hepatic IGF-1 mRNA than did Avian broilers and Wuding chickens. These results suggest that the GH part of the somatotropic axis is the main regulator of growth rate, while IGF-1 may regulate both growth rate and body weight. Selection for growth performance and body size have altered the expression profiles of somatotropic axis genes in a breed-, age-, and tissue-specific manner, and manner, and alteration of regulatory mechanisms of these genes might play an important role in the developmental characteristics of chickens.

Abstract B022: Metabolic and immunologic effects of the fasting mimicking diet in cancer patients

Abstract Background: The fasting mimicking diet (FMD), a plant-based, low-calorie, low-protein, low-carbohydrate diet, modulates systemic metabolism and anticancer immunity, and displays anticancer activity in many preclinical tumor models. However, safety, metabolic, and activity data in the clinical setting are lacking. Methods: At Fondazione IRCCS Istituto Nazionale dei Tumori, a prospective study is ongoing to assess feasibility, tolerability, and metabolic effects of the FMD in cancer patients (pts) following a 5-day FMD (700 Kcal on day 1 and 300 kCal on days 2-5) every 21-28 days. This study is enrolling pts with any cancer type (except for small cell lung cancer), stage, and concomitantly administered anticancer treatment. Main exclusion criteria are: insulin-dependent diabetes, severe comorbidities, BMI &amp;lt;20 kg/m2, recent unintentional weight loss &amp;gt;5%. We are regularly collecting blood and urine samples before FMD initiation and at diet completion to measure diet-induced changes of metabolites and growth factors. Here we report data on metabolic modifications detected in 38 pts after the first FMD cycle, and preliminary peripheral blood immunomonitoring in selected cases. Results: 38 pts were enrolled from January 2017 to July 2017. 29 had advanced disease, and 34 were receiving concomitant anticancer therapy at study enrollment. The most represented tumor types were breast (14), prostate (4), pancreatic (4), and lung (5) cancer. All pts completed at least one cycle of FMD, and no G3-G4 adverse event (AE) were reported. After the first FMD cycle, median glycemia was reduced by 15% (p&amp;lt;0.001), plasma IGF-1 levels by 27% (p&amp;lt;0.001), and insulin levels by 34% (p&amp;lt;0.001), while median triglyceride, total cholesterol, and uric acid levels increased by 31.4% (p=0.014), 11% (p&amp;lt;0.001), and 80% (p&amp;lt;0.001), respectively; finally, average urine ketone body levels were raised from 0.38 mg/dl (range 0-10) to 62 mg/dl (range 20-100). In 4 pts (3 breast, 1 lung) enrolled in the study, we preliminarily evaluated by 10-color cytofluorimetry the frequency and activation state of immune cell subsets in peripheral blood mononuclear cells before (day 0) and at the end (day 5) of the first FMD cycle. Our analyses revealed a rapid and marked decrease of monocytic myeloid-derived suppressor cells (MDSC)(CD11b+CD33+LINnegCD14+HLA-DRneg), mirrored by a concomitant increase of activated T cells (CD3+CD25+PD-1dim) and cytolytic NK cells (CD3negCD16+CD56dim). Granulocytic MDSC (CD11+CD33+LNnegHLA-DRnegCD15+) were also reduced in 3 pts, while the 4th patient experienced an increase of these cells due to the administration of granulocyte colony-stimulating factor (G-CSF). Conclusions: This interim analysis suggests that our FMD scheme induces remarkable modifications in systemic metabolism and immunity in a heterogeneous population of cancer pts. These data provide initial insights into the metabolic modulation mediated by FMD in clinical setting, pointing to a potential contribution of this approach in reestablishing effective antitumor immunity in cancer patients. Citation Format: Filippo de Braud, Claudio Vernieri, Veronica Huber, Agata Cova, Paola Squarcina, Monica Milano, Giovanni Fucà, Valter Longo, Licia Rivoltini. Metabolic and immunologic effects of the fasting mimicking diet in cancer patients [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr B022.

Diagnostic and Immunosuppressive Potential of Elevated Mir-424 Levels in Circulating Immune Cells of Ischemic Stroke Patients.

Our previous study demonstrated that microRNA-424 (miR-424) protected against experimental stroke through inhibition of microglial proliferation and activation by targeting cell cycle proteins. The purpose of this study was to further explore the clinical significance of miR-424 in peripheral immune cells of patients with acute ischemic stroke (AIS). Blood samples were collected from 40 patients within 6 hours of symptom onset and 27 control subjects. MiR-424 levels in lymphocytes, neutrophils and plasma were determined by quantitative realtime-PCR. The diagnostic sensitivity and specificity of miR-424 for stroke was evaluated by receiver operator characteristic (ROC) curve. The correlation between miR-424 levels and clinical data was analyzed using Pearson’s correlation test. Plasma levels of inflammatory mediators (TNF-α, IL-10) and neurotrophic factor (IGF-1) were detected by ELISA. Notably, miR-424 expression levels in lymphocytes and neutrophils increased after stroke, suggestive of its diagnostic value in ischemic stroke. MiR-424 levels in neutrophils were negatively correlated with infarct volume. Lymphocytic miR-424 levels were negatively correlated with the number of lymphocytes and the expression of cyclin-dependent kinase CDK6. Moreover, plasma TNF-α and IGF-1 levels increased and decreased, respectively, in stroke patients, and miR-424 levels in lymphocytes and neutrophils were both inversely correlated with plasma TNF-α, IL-10, or IGF-1 levels. In summary, miR-424 levels in peripheral immune cells has diagnostic potential for ischemic stroke, and might affect the severity of acute stroke by depressing the peripheral inflammatory response through CDK6-dependent pathway in lymphocytes or CDK6-independent pathway neutrophils.

Reduction in Bone Marrow Insulin-like Growth Factor-1 Levels Enhances Long-Term Hematopoietic Stem Cell Engraftment Following Bone Marrow Transplantation

Efficient donor hematopoietic stem cell (HSC) engraftment is critical for successful bone marrow transplantation (BMT) and requires interactions between donor HSC and host-derived HSC niche elements. Due to disruption of perivascular stem cell niches induced by myeloablative BMT conditioning, initial engraftment of HSC following BMT occurs in niches located near the endosteum. We have previously shown that myeloablative BMT conditioning with total body irradiation (TBI) induces expansion of endosteal niche osteolineage cells in a time course correlating with increases in bone marrow (BM) levels of insulin-like growth factor (IGF)-1. We also have shown that inhibition of IGF-1 Receptor (IGF1R) signaling blocks osteolineage cell expansion after TBI, resulting in poor engraftment of long-term (LT)-HSC after BMT and suggesting a critical role for IGF-1/IGF1R interactions in regulating engraftment after BMT. We now present data in which we have defined the cellular sources of BM IGF-1 following TBI and have surprisingly discovered that reduction in BM IGF-1 levels promotes LT-HSC retention at baseline and donor LT-HSC engraftment following BMT.Using mice with floxed IGF-1 alleles (IGF1L/L) and with tissue-specific expression of Cre-recombinase, we generated models with deletion of IGF-1 derived from mature osteolineage cells (Col1A1CreIGF1Exc), hematopoietic cells (CD45CreIGF1Exc), or liver (AlbCreIGF1Exc). We additionally generated a conditional IGF-1 deletion model (MX1CreIGF1Exc) in which polyI:polyC (pI:pC) treatment disrupts IGF-1 production from all 3 of the above sources.By qPCR analysis, CD45CreIGF1Exc BM showed marked reduction (>95%) in BM IGF-1 mRNA at baseline and following TBI, suggesting that hematopoietic cells produce most of the locally derived IGF-1 in BM. Unexpectedly however, neither deletion of osteoblast-derived (Col1A1CreIGF1Exc) nor hematopoietic cell-derived (CD45CreIGF1Exc) IGF-1 significantly reduced BM extracellular or intracellular IGF-1 protein levels at baseline, or extracellular BM IGF-1 levels following TBI. In contrast, elimination of liver-derived IGF-1 in AlbCreIGF1Exc mice not only reduced plasma IGF-1 levels by 80%, but surprisingly reduced BM extracellular IGF-1 protein levels by ≥80% both at baseline and 48 hours post-TBI, and reduced BM intracellular IGF-1 protein levels by >80% and >60% at baseline and post-TBI, respectively. These data suggest that most IGF-1 protein in BM during BMT is derived from liver. Conditional IGF-1 deletion in MX1CreIGF1Exc mice resulted in severe reduction of both BM IGF-1 mRNA and protein levels, combining effects seen in CD45CreIGF1Exc and AlbCreIGF1Exc mice. None of these models, however, showed deficits in TBI-induced endosteal cell expansion, suggesting that other ligands or perhaps only low levels of IGF-1 are required to induce IGFR1 signaling-dependent endosteal cell expansion.Unexpectedly, reduction of BM IGF-1 in ALBCreIGF1Exc and MX1CreIGF1Exc mice caused a 3-4 fold increase (% of total BM) in BM Lin-cKit+Sca1+CD48-CD150+ or Lin-cKit+Sca1+CD34-CD135- HSC. ALBCreIGF1Exc BM displayed enhanced multi-lineage long-term repopulating capacity in competitive transplant assays, proving that these cells are functional LT-HSC. Given this baseline LT-HSC enhancement, we asked if reduction in BM IGF-1 levels impacted capacity of ALBCreIGF1Exc BM niches to engraft donor HSC after BMT. Using competitive secondary transplantation assays to assess numbers of engrafted WT GFP+ LT-HSC 3 weeks after primary BMT into ALBCreIGF1Exc or control mice, we found that reduced IGF-1 in the ALBCreIGF1Exc BM microenvironment resulted in >2.5 fold enhancement of donor LT-HSC engraftment. In an initial search of downstream mediators of this effect, we discovered that reduction of IGF-1 levels in MX1CreIGF1Exc BM results in a 2.5-fold increase in post-TBI CXCL12 mRNA expression, suggesting that reducing BM IGF-1 may enhance donor LT-HSC engraftment by promoting LT-HSC homing and maintenance within HSC niches.Taken together our data define a critical role for IGF-1/IGF1R interactions in regulating the efficiency of donor HSC engraftment following BMT. Therapeutic strategies to reduce BM IGF-1 may prove to be a valuable approach to improving engraftment following clinical BMT. DisclosuresNo relevant conflicts of interest to declare.

Abstract 237: Increased NSCLC tumorigenesis in mice fed a high fat diet is associated with increased plasma IGF-1 levels and PD-1 expression in CD4+ tumor-infiltrating lymphocytes

Abstract Lung cancer is the leading cause of cancer-related mortality worldwide, and 85% of lung cancer cases are associated with tobacco use. Activating mutations in K-ras have been identified in ~25% of tobacco-associated lung adenocarcinomas. Using mouse models of K-ras-driven lung tumorigenesis, we previously demonstrated that deletion of the IGF-1 gene or reduction of systemic IGF-1 levels using the antidiabetic drug metformin markedly reduced tumor burden. Preclinical and clinical studies suggest that diet composition is the best predictor of IGF-1 levels. Therefore, we hypothesized that diets high in fat or carbohydrate would promote lung tumorigenesis by increasing systemic IGF-1 levels. To assess the effect of diet on systemic IGF-1 levels, 9 week old C57Bl/6J and A/J mice were fed standard cereal, high-carbohydrate, or high-fat (HFD) diets for 12 weeks. Compared to cereal-fed control mice, plasma IGF-1 and insulin levels were increased in both strains of mice fed a HFD, but not in mice fed a diet high in carbohydrate. This was not due to obesity, as only the C57Bl/6J mice fed a HFD had an increase in body weight. We then investigated the effect of HFD on lung tumorigenesis using two mouse models. In the first, C57Bl/6LA2 mice, which harbor a mutation in K-ras, were fed either cereal diet or HFD for 10 weeks following weaning. Lung tumor burden in the mice fed HFD was increased 2.7-fold compared to littermates fed cereal diet. In the second model, the tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1 butanone (NNK) was given by intraperitoneal injection to A/J mice beginning at 6 weeks of age. This carcinogen causes lung tumor development by inducing K-ras mutations. After 3 weekly injections of NNK, the mice were randomized to cereal diet or HFD for ten weeks. Mice fed HFD had a 60% increase in lung tumor burden. In both models, there was no relationship between the weight of the mice and lung tumor burden. Immunohistochemical analysis of the proliferation marker Ki-67 showed no significant difference in expression between tumors from mice fed a HFD or a cereal diet. Therefore, we evaluated tumor-infiltrating lymphocytes (TIL) from mice on both diets. Interestingly, both immunohistochemical analysis and flow cytometry demonstrated a 50% reduction in the number of TIL in mice fed HFD compared to mice fed a cereal diet. Additionally, HFD was associated with a 2-fold increase in PD-1+ CD4+ TIL, and the PD-1 staining intensity in these lymphocytes was significantly greater than in mice fed a cereal diet. These results may suggest that a high fat diet increases lung tumorigenesis by increasing systemic IGF-1 levels and by creating an immune-permissive tumor microenvironment. Citation Format: Regan M. Memmott, Krista Pearman, Joell Gills, Tony Tullot, Valerie Wong, Benjamin Singer, Kristin Lastwika, Franco D'Alessio, Phillip Dennis, Jeffrey William Norris. Increased NSCLC tumorigenesis in mice fed a high fat diet is associated with increased plasma IGF-1 levels and PD-1 expression in CD4+ tumor-infiltrating lymphocytes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 237. doi:10.1158/1538-7445.AM2017-237

Recombinant bovine growth hormone (rBGH) enhances somatic growth by regulating the GH-IGF axis in fingerlings of gilthead sea bream (Sparus aurata)

The growth hormone (GH)/insulin-like growth factors (IGFs) endocrine axis is the main growth-regulator system in vertebrates. Some authors have demonstrated the positive effects on growth of a sustained-release formulation of a recombinant bovine GH (rBGH) in different fish species. The aim of this work was to characterize the effects of a single injection of rBGH in fingerlings of gilthead sea bream on growth, GH-IGF axis, and both myogenic and osteogenic processes. Thus, body weight and specific growth rate were significantly increased in rBGH-treated fish respect to control fish at 6weeks post-injection, whereas the hepatosomatic index was decreased and the condition factor and mesenteric fat index were unchanged, altogether indicating enhanced somatic growth. Moreover, rBGH injection increased the plasma IGF-I levels in parallel with a rise of hepatic mRNA from total IGF-I, IGF-Ic and IGF-II, the binding proteins IGFBP-1a and IGFBP-2b, and also the receptors IGF-IRb, GHR-I and GHR-II. In skeletal muscle, the expression of IGF-Ib and GHR-I was significantly increased but that of IGF-IRb was reduced; the mRNA levels of myogenic regulatory factors, proliferation and differentiation markers (PCNA and MHC, respectively), or that of different molecules of the signaling pathway (TOR/AKT) were unaltered. Besides, the growth inhibitor myostatin (MSTN1 and MSTN2) and the hypertrophic marker (MLC2B) expression resulted significantly enhanced, suggesting altogether that the muscle is in a non-proliferative stage of development. Contrarily in bone, although the expression of most molecules of the GH/IGF axis was decreased, the mRNA levels of several osteogenic genes were increased. The histology analysis showed a GH induced lipolytic effect with a clear decrease in the subcutaneous fat layer. Overall, these results reveal that a better growth potential can be achieved on this species and supports the possibility to improve growth and quality through the optimization of its culture conditions.

Insulin-like growth factor-1 is a negative modulator of glucagon secretion.

Glucagon secretion involves a combination of paracrine, autocrine, hormonal, and autonomic neural mechanisms. Type 2 diabetes often presents impaired glucagon suppression by insulin and glucose. Insulin-like growth factor-I (IGF-1) has elevated homology with insulin, and regulates pancreatic β-cells insulin secretion. Insulin and IGF-1 receptors share considerable structure homology and function. We hypothesized the existence of a mechanism linking the inhibition of α-cells glucagon secretion to IGF-1. Herein, we evaluated the association between plasma IGF-1 and glucagon levels in 116 nondiabetic adults. After adjusting for age gender and BMI, fasting glucagon levels were positively correlated with 2-h post-load glycaemia, HOMA index and fasting insulin, and were negatively correlated with IGF-1 levels. In a multivariable regression, the variables independently associated to fasting glucagon were circulating IGF-1 levels, HOMA index and BMI, explaining 20.7% variation. To unravel the molecular mechanisms beneath IGF-1 and glucagon association, we investigated whether IGF-1 directly modulates glucagon expression and secretion in an in vitro model of α-cells. Our data showed that IGF-1 inhibits the ability of low glucose concentration to stimulate glucagon expression and secretion via activation of the phosphatidylinositol-3-kinase/Akt/FoxO1 pathway.Collectively, our results suggest a new regulatory role of IGF-1 on α-cells biological function.