Plasma IGF-I Research Articles

Administration of recombinant bovine somatotropin prior to fixed-time artificial insemination and the effects on fertility, embryo, and fetal size in beef heifers

Our objectives were to determine the effects of the administration of recombinant bovine somatotropin (bST) at the initiation of a fixed-time AI (TAI) protocol on concentrations of plasma IGF-1, follicle diameter, embryo/fetal size, and pregnancy rates in replacement beef heifers. Four hundred and fourteen Angus-based beef heifers were enrolled in a completely randomized design at 4 locations from January to July of 2016. All heifers were exposed to the 7-d CO-Synch + controlled internal drug release (CIDR) protocol where they received a 100-µg injection of GnRH and a CIDR insert on day -9, 25 mg of PGF2α at CIDR removal on day -2, followed by a 100-µg injection of GnRH and TAI 54 ± 2 h later on day 0. Within location, all heifers were randomly assigned to 1 of 2 treatments: 1) heifers that received 650 mg of bST on day -9 (BST; n = 191); or 2) heifers that did not receive bST on day -9 (CONTROL; n = 223). Blood samples were collected on day -9, 0, 28, and 60 to determine the plasma concentrations of IGF-1. Follicle diameter was determined on day -2 and 0 by transrectal ultrasonography. Pregnancy was diagnosed via transrectal ultrasonography on day 28 or 35, and again at least 30 d after the end of the breeding season. Embryo morphometry was assessed by measuring crown-to-rump length (CRL) on day 28, and fetal size was assessed by measuring crown-to-nose-length (CNL) on day 60. Concentrations of plasma IGF-1 did not differ between treatments on day -9 (P = 0.924), 28 (P = 0.075), and 60 (P = 0.792); however, concentrations of plasma IGF-1 were greater (P < 0.001) in BST-treated heifers at TAI (372.4 ± 16.6 vs. 193.7 ± 16.6 ng/ml). No differences (P = 0.191) were detected for follicle diameter between CONTROL and BST treatments on day -2 or 0. Pregnancy rates to TAI (PR/AI) were greater (P = 0.028) for CONTROL compared to BST heifers (42.5 ± 4.0 vs. 29.9 ± 4.1%). No differences (P = 0.536) in CRL were observed on day 28 between CONTROL and BST heifers. In addition, no difference (P = 0.890) was observed for CNL between CONTROL and BST treatments. Final pregnancy rates did not differ (P = 0.699) between treatments. The administration of bST to beef heifers at the initiation of a TAI protocol increased plasma concentrations of IGF-1 at TAI; however, failed to enhance follicle diameter, embryo/fetal size, and reduced PR/AI.

Morphological adaptation of sheep\u2019s rumen epithelium to high-grain diet entails alteration in the expression of genes involved in cell cycle regulation, cell proliferation and apoptosis

BackgroundThe objectives of this study were to characterize changes in the relative mRNA expression of candidate genes and proteins involved in cell cycle regulation, cell proliferation and apoptosis in the ruminal epithelium (RE) of sheep during high-grain (HG) diet adaptation.ResultsTwenty sheep were assigned to four groups with five animals each. These animals were assigned to different periods of HG diet (containing 40% forage and 60% concentrate mix) feeding. The HG groups received an HG diet for 7 (G7, n = 5), 14 (G14, n = 5) and 28 d (G28, n = 5), respectively. In contrast, the control group (CON, n = 5) was fed the forage-based diet for 28 d. The results showed that HG feeding linearly decreased (P < 0.001) the ruminal pH, and increased the concentrations of ruminal total volatile fatty acid (linear, P = 0.001), butyrate (linear, P < 0.001), valerate (quadratic P = 0.029) and the level of IGF-1 (quadratic, P = 0.043) in plasma. The length (quadratic, P = 0.004), width (cubic, P = 0.015) and surface of the ruminal papillae (linear, P = 0.003) were all enlarged after 14 d of HG diet feeding. HG feeding cubically increased the number of cell layers forming the stratum corneum (SC, P < 0.001) and the thickness of the SC (P < 0.001) and stratum basale (P < 0.001). The proportion of basal layer cells in the RE decreased (linear, P < 0.001) in the G0/G1-phase, but it increased linearly (P = 0.006) in the S-phase and cubically (P = 0.004) in the G2/M-phases. The proportion of apoptosis cells in G7, G14 and G28 was reduced compared to the CON (quadratic, P < 0.001). HG diet feeding linearly decreased the mRNA expression of Cyclin E1 (P = 0.021) and CDK-2 (P = 0.001) and (P = 0.027) the protein expression of Cyclin E1. Feeding an HG diet linearly increased the mRNA expression of genes IGFBP-2 (P = 0.034) and IGFBP 5 (P < 0.009), while linearly decreasing (P < 0.001) the IGFBP 3 expression. The expression of cell apoptosis gene Caspase 8 decreased (quadratic, P = 0.012), while Bad mRNA expression tended to decrease (cubic, P = 0.053) after HG feeding.ConclusionsThese results demonstrated sequential changes in rumen papillae size, cell cycle regulation and the genes involved in proliferation and apoptosis as time elapsed in feeding a high-grain diet to sheep.

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.

Effect of adipocyte-derived IGF-I on adipose tissue mass and glucose metabolism in the Berlin Fat Mouse

Besides liver, IGF-I is expressed in adipose tissue. However, the effects of this local IGF-I on adipose tissue and metabolism are unclear. We generated adipocyte-specific knock-out mice on the background of the Berlin Fat Mouse Inbred (BFMI) line to evaluate the contribution of adipocyte-IGF-I on glucose metabolism and adipose tissue development. BFMI mice are obese, non-diabetic with elevated plasma insulin and IGF-I concentration. The knock-out in adipocytes led to a total white adipose tissue expression of 50–60% due to unaltered Igf-1 expression in stromavascular cells. The lack of IGF-I from adipocytes did not alter plasma IGF-I concentration. BFMIChr3-Igf-I-KOQ-AT mice had reduced adipose tissue mass in most depots. During oral glucose tolerance tests, BFMIChr3-Igf-I-KOQ-AT mice showed an impaired glucose clearance (p = .03). Interestingly, insulin action was enhanced during insulin tolerance tests (p = .05). In conclusion, adipocyte-specific IGF-I ablation in obese BFMI mice results in reduced adipose tissue mass and thereby alters glucose metabolism.

Winter vitamin D3 supplementation does not increase muscle strength, but modulates the IGF-axis in young children.

To explore whether muscle strength, the insulin-like growth factor axis (IGF-axis), height, and body composition were associated with serum 25-hydroxyvitamin D [25(OH)D] and affected by winter vitamin D supplementation in healthy children, and furthermore to explore potential sex differences. We performed a double-blind, placebo-controlled, dose-response winter trial at 55ºN. A total of 117 children aged 4-8years were randomly assigned to either placebo, 10, or 20µg/day of vitamin D3 for 20 weeks. At baseline and endpoint, we measured muscle strength with handgrip dynamometer, fat mass index (FMI), fat free mass index (FFMI), height, plasma IGF-1, IGF-binding protein 3 (IGFBP-3), and serum 25(OH)D. At baseline, serum 25(OH)D was positively associated with muscle strength, FFMI, and IGFBP-3 in girls only (all p < 0.01). At endpoint, baseline-adjusted muscle strength, FMI and FFMI did not differ between intervention groups. However, baseline-adjusted IGF-1 and IGFBP-3 were higher after 20µg/day compared to placebo (p = 0.043 and p = 0.006, respectively) and IGFBP-3 was also higher after 20µg/day compared to 10µg/day (p = 0.011). Children tended to be taller after 20µg/day compared to placebo (p = 0.064). No sex interactions were seen at endpoint. Avoiding the winter-related decline in serum 25(OH)D may influence IGF-1 and IGFBP-3 in children. Larger trials are required to confirm these effects, and the long-term implication for linear growth.

Effects of Transport Duration and Environmental Conditions in Winter or Summer on the Concentrations of Insulin-Like Growth Factors and Insulin-Like Growth Factor-Binding Proteins in the Plasma of Market-Weight Pigs.

In previous work using market-weight pigs, we had demonstrated that insulin-like growth factors (IGFs) and insulin-like growth factor binding proteins (IGFBPs) are regulated during shipment characterized by changing conditions of stress due to loading or unloading, transportation, lairage, and slaughter. In addition, we found in a previous study that IGFBP-2 concentrations were lower in pigs transported for longer periods of time. Therefore, we performed a more detailed study on the effects of transport duration and season on the plasma concentrations of IGFs and IGFBPs in adult pigs. For the study, exsanguination blood was collected from 240 market-weight barrows that were transported for 6, 12, or 18 h in January or July. IGF-I and -II were detected using commercial ELISAs whereas IGFBPs were quantified by quantitative Western ligand blotting. In addition, established markers of stress and metabolism were studied in the animals. The results show that plasma concentrations of IGFBP-3 were significantly reduced after 18 h of transport compared to shorter transport durations (6 and 12 h; p < 0.05). The concentrations of IGF-I in plasma were higher (p < 0.001) in pigs transported 12 h compared to shorter or longer durations. Season influenced plasma concentrations of IGFBP-3 and IGF-II (p < 0.05 and p < 0.01, respectively). Neither transport duration nor differential environmental conditions of winter or summer had an effect on glucocorticoids, albumin, triglycerides, or glucose concentrations (p > 0.05). However, low-density lipoprotein concentrations decreased after 18 h compared to 6 h of transport (p < 0.05), whereas high-density lipoprotein concentrations were higher (p < 0.05) in pigs transported for 12 or 18 h compared to those transported for only 6 h. Our findings indicate differential regulation of IGF-compounds in response to longer transport duration or seasonal changes and support current evidence of IGFs and IGFBPs as innovative animal-based indicators of psycho-social or metabolic stress in pigs.

Reproductive responses to sexually active buck of does treated with melatonin when body weight/body condition is increasing or decreasing

When the sexual activity of bucks is minimal, there is a minimal male effect on does regardless of their body weight (BW)/body condition (BC) and whether does are treated with melatonin or not. The study examines whether sexually active bucks can induce an adequate male effect in does with an increasing or decreasing trajectory of change in BW/BC when does are or not treated with melatonin. During natural anoestrus, 46 Blanca Andaluza does were assigned to two groups: 1) low BW/low BC group in which does were fed 1.9 times maintenance requirements for dietary energy for gaining BW/BC (LLg group; n = 23); or 2) a high BW/high BC group in which the does were fed 0.4 times maintenance requirements for dietary energy that resulted in a loss of BW/BC (HHl group; n = 23). There were similar numbers of does in each group that were treated or not treated with melatonin (MEL). Following 48 days of isolation from bucks, four sexually active individuals fitted with marking harnesses were transferred to the paddock containing the does of each group. Blood samples were collected by jugular venipuncture (before the distribution of concentrate) twice per week. The effect of the treatments (increasing or decreasing BW/BC and melatonin) on the different variables that were assessed were analysed using an ANOVA or the Fisher-Freeman-Halton exact probability test as necessary. During the 35 days after treatments were applied, the percentage of females expressing oestrous and having an ovulation were greater in the LLg + MEL than HHl-MEL subgroup (P < 0.05). The interaction of nutrition × melatonin treatment had a significant effect on reproduction of does (P < 0.05). This could be explained by the greater plasma glucose and IGF-1 and lesser plasma non-esterified fatty acid concentrations in does with increasing BW/BC (P < 0.01), and the greater IGF-1 concentrations of MEL-treated females (P < 0.01). The LH concentration and pulsatile release of this hormone from the pituitary were also modified by the presence of the males (P < 0.01). Furthermore, the LLg + MEL-treated does were responsive to the presence of bucks (P < 0.05). The present results indicate sexually active males cannot induce an adequate reproductive response in females with decreasing BW/BC even when does are being treated with melatonin. The presence of bucks enhanced the doe reproductive response when does were treated with melatonin and a pattern of increasing BW/BC.

Vitamin A and E Nutritional Status in Relation to Leptin, Adiponectin, IGF-I and IGF-II in Early Life - a Birth Cohort Study

The metabolic health effects of vitamin A and E nutritional status in early life are largely unknown. We assessed whether vitamin A and vitamin E nutritional status may affect circulating leptin, adiponectin, insulin-like growth factor (IGF)-I and IGF-II levels in early life in humans. In a singleton birth cohort (n = 248), vitamin A and E nutritional status in fetuses/newborns were assessed by cord plasma concentrations of retinol, β-carotene, α- and γ-tocopherols. The primary outcomes were cord plasma leptin, adiponectin, IGF-I and IGF-II concentrations. Cord plasma retinol was significantly positively correlated to IGF-I in girls (r = 0.42, P < 0.0001) but not in boys (r = 0.14, P = 0.11). Adjusting for maternal and newborn’s characteristics, one log unit increase in cord plasma retinol was associated with a 28.0% (95% CI: 11.1–47.5%) increase in IGF-I in girls (P < 0.001) but not in boys (P = 0.75). One log unit increment in cord plasma α-tocopherol was associated with a 6.6% (0.4–12.3%) decrease in adiponectin (P = 0.04), while one log unit increment in cord plasma γ-tocopherol was associated with a 21.2% (4.7–34.8%) decrease in leptin (P = 0.01). There may be a sex-specific association between retinol and IGF-I, a negative association between α-tocopherol and adiponectin, and a negative association between γ-tocopherol and leptin in early life in humans.

Effect of starter diet supplementation on rumen epithelial morphology and expression of genes involved in cell proliferation and metabolism in pre-weaned lambs

Starter feeding is usually used in lamb production to improve rumen development and to facilitate the weaning process, but molecular mechanism of which is not well understood. Therefore, the objective of this study is to investigate the effect of starter feeding on the expression of ruminal epithelial genes involved in cell proliferation, apoptosis and metabolism in pre-weaned lambs. We selected eight pairs of 10-day-old lamb twins. One twin was fed ewe milk (M, n=8), while the other was fed ewe milk plus starter (M+S, n=8). The lambs were sacrificed at 56 days age. Results showed that the lambs fed M+S had lower pH in the rumen and a higher concentration of acetate, propionate, butyrate and total volatile fatty acid (VFA). Compared with the M group, the concentration of β-hydroxybutyric acid in plasma had an increased trend, and the concentration of IGF-1 in plasma had an decreased trend in the M+S group. The length, width and surface of rumen papillae increased in the M+S group compared with the M group; this was associated with increased cell layers in the stratum corneum, stratum granulosum and total epithelia. Messenger RNA (mRNA) expression of proliferative genes of cyclin A, cyclin D1 and cyclin-dependent kinase 2 in the ruminal epithelia of M+S lambs was increased compared with M only lambs. The mRNA expression of apoptosis genes of caspase-3, caspase-8, B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax) in the M+S group was decreased compared with M group, but the ratio of Bcl-2 to Bax were not changed between the two groups. Expression of IGF-1 mRNA was decreased, but the mRNA expression of IGF-1 receptor was higher in ruminal epithelia in the M+S group. Furthermore, the mRNA expression of VFA absorption and metabolism genes of β-hydroxybutyrate dehydrogenase isoforms 1 and 3-hydroxy-3-methylglutaryl-CoA lyase had an increased trend in the M+S group than in the M group, but the mRNA expression of 3-hydroxy-3-methylglutaryl-CoA synthase isoform 1, monocarboxylate transporter isoform 1 and putative anion transporter isoform 1 had a decreased trend in the M+S group than in the M group. These results suggest that starter feeding increased proliferation and inhibited apoptosis of ruminal epithelial cells, and may promote the VFA metabolism in ruminal epithelium in pre-weaned lambs. These findings provide new insights into improving rumen development by nutritional intervention strategies in pre-weaned lambs.

Supplementing a yeast-derived product to enhance productive and health responses of beef steers

This experiment evaluated the impacts of supplementing a yeast-derived product (Celmanax; Church & Dwight Co., Inc., Princeton, NJ, USA) on productive and health responses of beef steers, and was divided into a preconditioning (days 4 to 30) and feedlot receiving phase (days 31 to 69). In all, 84 Angus × Hereford steers were weaned on day 0 (BW=245±2 kg; age=186±2 days), and maintained in a single group from days 0 to 3. On day 4, steers were allocated according to weaning BW and age to a 21-pen drylot (4 steers/pen). Pens were randomly assigned to (n=7 pens/treatment): (1) no Celmanax supplementation during the study, (2) Celmanax supplementation (14 g/steer daily; as-fed) from days 14 to 69 or (3) Celmanax supplementation (14 g/steer daily; as-fed) from days 31 to 69. Steers had free-choice access to grass-alfalfa hay, and were also offered a corn-based concentrate beginning on day 14. Celmanax was mixed daily with the concentrate. On day 30, steers were road-transported for 1500 km (24 h). On day 31, steers returned to their original pens for the 38-day feedlot receiving. Shrunk BW was recorded on days 4, 31 and 70. Feed intake was evaluated daily (days 14 to 69). Steers were observed daily (days 4 to 69) for bovine respiratory disease (BRD) signs. Blood samples were collected on days 14, 30, 31, 33, 35, 40, 45, 54 and 69, and analyzed for plasma cortisol, haptoglobin, IGF-I, and serum fatty acids. Preconditioning results were analyzed by comparing pens that received (CELM) or not (CONPC) Celmanax during the preconditioning phase. Feedlot receiving results were analyzed by comparing pens that received Celmanax from days 14 to 69 (CELPREC), days 31 to 69 (CELRECV) or no Celmanax supplementation (CON). During preconditioning, BRD incidence was less (P=0.03) in CELM v. CONPC. During feedlot receiving, average daily gain (ADG) (P=0.07) and feed efficiency (P=0.08) tended to be greater in CELPREC and CELRECV v. CON, whereas dry matter intake was similar (P⩾0.29) among treatments. No other treatment effects were detected (P⩾0.20). Collectively, Celmanax supplementation reduced BRD incidence during the 30-day preconditioning. Moreover, supplementing Celmanax tended to improve ADG and feed efficiency during the 38-day feedlot receiving, independently of whether supplementation began during preconditioning or after feedlot entry. These results suggest that Celmanax supplementation benefits preconditioning health and feedlot receiving performance in beef cattle.

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.

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.

Influence of ad libitum milk replacer feeding and butyrate supplementation on the systemic and hepatic insulin-like growth factor I and its binding proteins in Holstein calves

Ad libitum milk feeding and butyrate (B) supplementation have the potential to stimulate postnatal growth and development in calves. The somatotropic axis is the main endocrine regulator of postnatal growth and may be affected by both ad libitum milk replacer (MR) feeding and B supplementation in calves. We hypothesized that ad libitum MR feeding and B supplementation stimulate systemic and hepatic insulin-like growth factor (IGF)-I and IGF binding proteins (IGFBP) in preweaning calves. Sixty-four (32 male, 32 female) Holstein calves were examined from birth until wk 11 of life. Calves received MR either ad libitum (Adl) or restrictively (6 L/d; Res). In each feeding group half of the calves received a MR with 0.24% butyrate and the other half received same MR without butyrate. Ad libitum MR feeding was performed from d 4 until wk 8 of age. From wk 9 to 10, Adl and Res calves were gradually weaned and were fed 2 L/d until the end of the trial. Concentrate, hay, and water were freely available. Feed intake was measured daily and body weight weekly. Blood samples for analyzing plasma concentrations of glucose, insulin, IGF-I, and IGFBP-2, -3, and -4 were taken on d 1, 2, 4, and 7, then weekly or every other week (IGFBP) until wk 11 of life. Liver samples were taken on d 50 and at the end of the study (d 80) to measure gene expression of the growth hormone receptor 1A (GHR1A), IGF1, IGFBP1 to 4, and of the IGF Type 1 and insulin receptor in the liver. Intake of MR and body weight were greater, but concentrate intake was lower in Adl than in Res. Plasma concentrations of IGF-I and IGFBP-3 were greater and plasma concentration of IGFBP-2 was lower in Adl than in Res during the ad libitum milk feeding period. After reduction of MR in both groups to 2 L/d plasma concentrations of IGF-I and IGFBP-4 were lower and plasma concentration of IGFBP-2 was higher in Adl than in Res. Supplementation of B depressed plasma IGF-I from wk 1 to 4 and in wk 9. On d 50, mRNA abundance of the GHR1A and IGF1 was greater and of IGFBP2 mRNA was lower in Adl than in Res. At d 80, IGFBP2 mRNA was greater in Adl than in Res, and IGFBP2 mRNA increased with B supplementation. Ad libitum MR feeding stimulated the systemic and hepatic IGF system and mirrored the greater growth rate during the ad libitum MR feeding, whereas butyrate supplementation partly reduced the systemic and hepatic IGF system.

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.

Interaction between supplemental zinc oxide and zilpaterol hydrochloride on growth performance, carcass traits, and blood metabolites in feedlot steers.

Interactive effects of supplemental Zn and zilpaterol hydrochloride (ZH) were evaluated in feedlot steers ( = 40; 652 kg ± 14 initial BW) to determine their impact on feedlot performance, blood constituents, and carcass traits. The study was conducted as a randomized complete block design with a 2 × 2 factorial treatment arrangement. Steers were blocked by BW and randomly assigned to treatments. Factors consisted of supplemental Zn (60 or 300 mg/kg diet DM) and ZH (0 or 8.33 mg/kg) in the diets. For diets supplemented with 300 mg Zn/kg DM, 60 mg Zn/kg was supplemented as zinc sulfate and 240 mg Zn/kg was supplemented as zinc oxide, and the diet was fed for 24 d. Zilpaterol hydrochloride was fed for 21 d followed by a 3-d withdrawal. Cattle were housed in partially covered individual feeding pens equipped with automatic waterers and fence-line feed bunks and were fed once daily for ad libitum intake. Plasma samples were collected on d 0 and 21 to assess changes in Zn, plasma urea nitrogen (PUN), glucose, and lactate concentrations, and serum samples were collected on d 21 to assess IGF-1 concentration. On d 25, cattle were weighed and transported 450 km to a commercial abattoir for harvest; HCW and incidence of liver abscesses were recorded. Carcass data were collected after 36 h of refrigeration. Data were analyzed as a mixed model with Zn, ZH, and Zn × ZH as fixed effects; block as a random effect; and steer as the experimental unit. No interaction or effects of Zn or ZH were observed for IGF-1 concentration, plasma glucose, or lactate concentrations ( ≥ 0.25). No interaction between Zn and ZH was observed for PUN concentration, but PUN decreased with ZH ( < 0.01). There were no effects of ZH or Zn on ADG, DMI, final BW, feed efficiency, HCW, back fat, KPH, quality grade, or incidence of liver abscesses ( > 0.05). Zinc supplementation tended ( = 0.08) to improve the proportion of carcasses grading USDA Choice. Feeding ZH decreased yield grade ( = 0.05) and tended to increase LM area ( = 0.07). In conclusion, increasing dietary concentrations of Zn does not impact response to ZH, but feeding ZH altered circulating concentrations of PUN.

Association of maternal breast milk and serum levels of macronutrients, hormones, and maternal body composition with infant's body weight.

This study was aimed to investigate the association of maternal serum and breast-milk levels of macronutrients, hormones, growth factors, and maternal body composition with infant's body weight. Eighty mother-infant pairs comprised 40 with overweight or obese infant and 40 with normal-weight infant were enrolled in this study. The level of ghrelin, Leptin, adiponectin, EGF, and IGF1 in plasma and breast milk were assessed. Daily breast milk intake and macronutrient concentration along with anthropometric indices of mother-infant pairs were also assessed. No significant differences were observed in concentrations of serum hormones between two groups (p > 0.05). However, hormones levels in maternal serum were higher than those in breast milk. A significant positive correlation was found between serum EGF and ghrelin (r = 0.57, p = 0 < 0001). Higher IGF1 in serum showed a significant association with its milk counterpart (r = 0.37). Current mother's weight was associated with infant's weight at the 2nd and 6th month (B = 0.023 p = 0.04, B = 0.055 p = 0.005). The breast-milk macronutrient content was not comparable between two groups. However, the average daily breast milk consumption in obese infants was higher than normals (p = 0.001). Milk EGF and leptin were related to a decrease of 59% and 46% the odds of obese infant development, respectively. There was a significant association of milk EGF and ghrelin with birth weight (B = -0.19, p = 0.04 and B = -0.2, p = 0.04, respectively), and also serum leptin with infant's body weight at the 6th month. Our findings provide a positive association of maternal weight, daily breast milk intake, EGF, and ghrelin with infant's body weight.

Effect of Chronic Alcohol Abuse on Anabolic and Catabolic Signaling Pathways in Human Skeletal Muscle.

Animal studies showed that alcoholic myopathy is characterized by the reduction in myofiber cross-sectional area (CSA) and by impaired anabolic signaling. The goal of this study was to compare changes in CSA and fiber type composition with modifications in anabolic and catabolic signaling pathways at the early stages of alcohol misuse in humans. Skeletal muscle samples from 7 male patients with chronic alcohol abuse (AL; 47.7±2.0years old; alcohol misuse duration 7.7±0.6years) were compared with muscle from a control group of 7 healthy men (C; 39.7±5.0years old). Biopsies from vastus lateralis muscles were taken and analyzed for the changes in fiber type composition, fiber CSA, and for the alterations in anabolic and catabolic signaling pathways. AL patients did not have detectable clinical myopathy symptoms or muscle fiber atrophy, but the relative proportion of fast fibers was increased. There was a significant decrease in IGF-1 in plasma and IRS-1 protein content in muscle of AL group. Levels of total and phosphorylated p70S6K1, GSK3β, and p90RSK1 were not different between AL and C groups. Muscle of AL patients had increased mRNA expression of HSP70 and HSP90. A marker of anabolic pathway p-4E-BP1 was decreased, while catabolic markers (MuRF-1, MAFbx, ubiquitinated proteins) were increased in AL patients when compared with C group. At the early stages of alcohol misuse in humans, changes in the regulation of anabolic and catabolic signaling pathways precede the development of skeletal muscle atrophy and manifestation of clinical symptoms of alcoholic myopathy.

Physiologic, health, and performance responses of beef steers supplemented with an immunomodulatory feed ingredient during feedlot receiving.

One hundred eight Angus × Hereford steers, originating from 7 cow-calf were obtained from an auction yard on d -2 and transported by road (800 km; 12 h) to an experimental feedlot facility. Upon arrival on d -1, shrunk BW was recorded and steers were grouped with free-choice access to grass hay, mineral supplement, and water. On d 0, steers were ranked by source and shrunk BW and assigned to 1 of 18 pens (6 steers/pen). Pens were allocated to 1) no immunomodulatory ingredient supplementation during feedlot receiving (CON), 2) supplementation with OmniGen-AF (OMN; 22 g/steer daily, as-fed basis; Phibro Animal Health Corp., Teaneck, NJ) from d 0 to 30, or 3) 2 oral capsules of Stocker Immune Primer on d 0 + 15 g/steer daily (as-fed basis) of Stocker Preconditioned Premix (Ramaekers Nutrition, Santa Cruz, CA) from d 7 to 30 (IPF). From d 0 to 80, steers had free-choice access to grass hay and water and received a corn-based concentrate. Feed DMI was recorded from each pen, and steers were assessed for bovine respiratory disease (BRD) signs daily. Steers were vaccinated against BRD pathogens on d 0 and 21. Final shrunk BW was recorded on d 81, and blood samples were collected on d 0, 3, 7, 10, 14, 21, 31, 42, 56, and 73. Steer ADG and final BW were greater ( ≤ 0.05) in CON steers than in OMN and IPF steers (1.23, 0.76, and 1.06 kg/d [SEM 0.06], respectively, and 320, 282, and 307 kg [SEM 4], respectively) and ( < 0.01) in IPF steers than in OMN steers. No treatment effects were detected ( ≥ 0.76) for BRD incidence (66 ± 4%) and DMI, whereas G:F was greater ( < 0.01) in OMN steers than in CON steers. Mean plasma cortisol concentration was greater ( = 0.01) in CON steers than in OMN and IPF steers. Plasma haptoglobin concentrations tended ( = 0.10) to be greater in CON steers than in IPF steers on d 3, were greater ( = 0.04) in IPF steers than in CON steers on d 7, and tended ( = 0.10) to be less in OMN steers than in IPF and CON steers on d 21. Blood mRNA expression of was greater ( ≤ 0.05) in OMN and IPF steers than in CON steers on d 3 and in OMN steers than in CON and IPF steers on d 14. Blood mRNA expression of was greater ( ≤ 0.05) in OMN and IPF steers than in CON steers on d 10. Plasma IGF-I concentrations, serum antibody titers to BRD pathogens, and blood mRNA expression of , , , and did not differ ( ≥ 0.21) among treatments. Collectively, the immunomodulatory feed ingredients evaluated herein impacted adrenocortical and innate immune responses but failed to mitigate BRD incidence and improve performance of receiving cattle.

Milk yield and genomewide expression profiling in the mammary gland of beef primiparous cows in response to the dietary management during the pre- and postweaning periods.

Accelerated growth programs during prepubertal periods have been promoted to advance the first calving of beef heifers. The objectives of the present study were to evaluate nutrition-induced changes on first lactation milk yield and composition and on gene expression of the mammary gland in Parda de Montaña primiparous cows. Female calves ( = 16) were involved in a 2 × 2 factorial experiment. In the preweaning period (PRE-W; 0-6 mo), female calves were either fed a creep feed supplement (Creep) or fed only their dam's milk (Control). In the postweaning period (POST-W; 6-15 mo), heifers received either a high-energy diet (91.7 MJ/d) or a moderate-energy diet (79.3 MJ/d). All the heifers were managed together from breeding (15 mo) to the end of their first lactation (32 mo). Animal performance; milk production and quantity during the first lactation; plasma glucose, IGF-I, and leptin concentrations; and RNA samples from the mammary gland at the end of the first lactation of the primiparous cows (32 mo) were analyzed. The BW and ADG of the primiparous cow during its first lactation were not different among treatments; however, creep feeding during PRE-W reduced milk production ( < 0.01), milk CP, crude fat, lactose, nonfat solids, and casein content throughout lactation and increased somatic cell count in the third ( < 0.05) and fourth month of lactation ( < 0.10). The energy level during the POST-W had no effect on milk production and quality. Gene expression in the mammary gland was affected by the diet in the PRE-W and POST-W, with the PRE-W diet having the greatest impact. During the PRE-W, creep feeding resulted in upregulation of genes related to immune response and chemokine activity, suggesting that these animals might be in a compromised immune status. Therefore, this strategy would not be recommendable; meanwhile, increasing the energy level in the diet during the POST-W would be recommendable, because it had no deleterious effects on milk yield and composition.

Mammalian target of rapamycin signaling and ubiquitin proteasome–related gene expression in 3 different skeletal muscles of colostrum- versus formula-fed calves

The rates of protein turnover are higher during the neonatal period than at any other time in postnatal life. The mammalian target of rapamycin (mTOR) and the ubiquitin-proteasome system are key pathways regulating cellular protein turnover. The objectives of this study were (1) to elucidate the effect of feeding colostrum versus milk-based formula on the mRNA abundance of key components of the mTOR pathway and of the ubiquitin-proteasome system in skeletal muscle of neonatal calves and (2) to compare different muscles. German Holstein calves were fed either colostrum (COL; n = 7) or milk-based formula (FOR; n = 7) up to 4 d of life. The nutrient content in formula and colostrum was similar, but formula had lower concentrations of free branched-chain AA (BCAA) and free total AA, insulin, and insulin-like growth factor (IGF)-I than colostrum. Blood samples were taken from d 1 to 4 before morning feeding and before and 2 h after the last feeding on d 4. Muscle samples from M. longissimus dorsi (MLD), M. semitendinosus (MST), and M. masseter (MM) were collected after slaughter on d 4 at 2 h after feeding. The preprandial concentrations of free total AA and BCAA, insulin, and IGF-I in plasma changed over time but did not differ between groups. Plasma free total AA and BCAA concentrations decreased in COL, whereas they increased in FOR after feeding, resulting in higher postprandial plasma total AA and BCAA concentrations in FOR than in COL. Plasma insulin concentrations increased after feeding in both groups but were higher in COL than in FOR. Plasma IGF-I concentrations decreased in COL, whereas they remained unchanged in FOR after feeding. The mRNA abundance of mTOR and ribosomal protein S6 kinase 1 (S6K1) in 3 different skeletal muscles was greater in COL than in FOR, whereas that of eukaryotic translation initiation factor 4E binding protein 1 (4EBP1) was unaffected by diet. The mRNA abundance of ubiquitin activating enzyme (UBA1) and ubiquitin conjugating enzyme 1 (UBE2G1) enzymes was not affected by diet, whereas that of ubiquitin conjugating enzyme 2 (UBE2G2) was greater (MLD) or tended to be greater (MM) in COL than in FOR. The mRNA abundance of atrogin-1 in MLD and MST was lower in COL than in FOR, whereas that of muscle ring finger protein-1 (MuRF1) was greater (MST) or tended to be greater (MLD). The abundance of MuRF1 mRNA was highest in MST, followed by MLD, and was lowest in MM. The results indicate that colostrum feeding may stimulate protein turnover that may result in a high rate of protein deposition in a muscle type-specific manner. Such effects seem to be mediated by the postprandial increase in plasma insulin.