Contribution of insulin-like growth factor system and growth hormone insulin-like growth factor 1 axis genes to heterosis in a bovine fetus model

Heterosis, the superiority of hybrids over the average of purebred parents, has been used for centuries to obtain higher yields in animal production. Molecular mechanisms of heterosis remain poorly understood and traditional genetic models based on dominance and overdominance largely fail to explain heterosis. This thesis is based on a bovine (Bos taurus × Bos indicus) heterosis model with high levels of heterosis in birthweight and postnatal growth and development associated with increased plasma insulin-like growth factor 1 (IGF1) concentrations. We hypothesised that heterosis is programmed prenatally and orchestrated by the IGF system and the growth hormone (GH)-IGF1 axis, which are fundamental for pre- and postnatal growth and development. We further hypothesised that epigenetic mechanisms involved in control of IGFs, i.e. as miRNA interference and retrotransposon insertion, contribute to heterosis. The aims of this project were to study the contribution of IGF system and GH-IGF1 axis transcripts, and epigenetic regulatory elements, on fetal growth and development of purebred Angus and Brahman cattle and their reciprocal crosses. Quantitative real time-PCR was used to quantify transcript abundance of IGF1 overall transcript, IGF1 class 1 and class 2, IGF1R, insulin receptor (IR) overall transcript, IR-A, IR-B, GH, GHR overall transcript, GHR-1A, GHR-1B, GHR-1C, insulin-like growth factor binding protein 1 (IGFBP1), IGFBP2, IGFBP3, IGFBP4, IGFBP5, IGFBP6, IGFBP7 and IGFBP8, in brain, cotyledon, heart, kidney, liver, lung, skeletal muscle and testis of Day-48 embryos, Day-153 fetuses and 12-month old juveniles. A miRNA abundance profile of fetal liver was obtained using miRNA arrays. Genetic, fetal sex and heterosis effects on transcript abundances were estimated using general linear models. Lack of data on developmental-stage and tissue-specific expression required an initial comparative gene expression study across key developmental stages and tissues. IGF system and GH-IGF1 axis transcripts showed tissue-specific expression patterns that differed across developmental stages. There was no detectable GH mRNA in tissues studied. The abundance of most transcripts in juvenile tissue was lower than in fetal tissue, except in liver, which showed increased IGF1, GHR and IGFBP4 expression and no change for IR, IGFBP1, IGFBP3 and IGFBP6 transcript. Our data showed negative or no molecular heterosis for liver IGFBP transcripts. Reduced expression of these IGF-modulators suggested an increase in available IGF1 in the fetus. We found molecular heterosis in liver GHR, as the major GHR downstream pathways involve IGF1, we concluded that heterosis in liver IGF1 class 2 transcripts was a result of increased liver GHR-1A mRNA. Several miRNAs, predicted to target 3’ UTRs of IGF system genes and GHR, were differentially expressed in different genotypes and may have a regulatory role in transcription of IGF system and GHR genes in bovine fetal liver. However, more experiments with an increased sample size for miRNA profiling are required to assess this further. Among studied tissues, fetal liver appears to be the most important tissue to study the molecular mechanisms of heterosis. In conclusion, it was demonstrated that mRNA transcripts and miRNAs in the developmentally important IGF system, and GHR transcripts, contribute to molecular heterosis in the bovine model. We propose that liver GHR-1A - IGF1 class 2 transcripts are important factors in molecular heterosis which may contribute to the reported heterosis in birth weight. Furthermore, miRNAs that regulate IGF system/GHR transcripts may contribute to bovine molecular and phenotypic heterosis postnatally.Thesis (Ph.D.) -- University of Adelaide, School of Animal & Veterinary Sciences, 201

Učinak kratkotrajne primjene hormona rasta i treninga snage na histopatološke promjene tkiva štitnjače i mutaciju gena BRAF (T1799A) u smeđeg štakora (Rattus norvegicus)

High levels of growth hormone accelerate mitosis rate but decrease the apoptosis process in its target organs. These events might cause the initiation of different cancer types. Thus, the main aims of this study were assessing the effects of short term growth hormone administration and resistance training on the histopathology and detection of the BRAF-V600E mutation in the thyroid tissue of male Rattus norvegicus brown rats. Thirty-two rats were randomly divided into four groups. After 8 weeks of the experiment (i.m), thyroid tissue and blood samples of saline (CS), resistance training+saline (RS), growth hormone (2 mg/kg) (GI) and resistance training+growth hormone (2 mg/kg) (RG) were taken to evaluate histopathology, the BRAF T1799A mutation of thyroid tissue, and circulating levels of IGF-1 and IGFBP-3. The protocol of training consisted of rats climbing a ladder while carrying weights (3 sets/5 reps). Microscopic evaluation of thyroid tissue did not show any histopathological changes, and there were no mutations in the studied region of the BRAF sequence. Serum IGF-1 concentration was significantly lower in the RS group than in other groups (P<0.05). However, serum IGFBP-3 concentration did not change significantly in the RS group. Moreover, serum IGF-1 and IGFBP-3 concentrations were significantly higher in the GI and RG groups than in the others (P<0.05). In conclusion, the decrement of serum IGF-1 concentration and IGF-1/IGFBP-3 ratio after resistance training might decrease the risk of cancer. Furthermore, short term growth hormone administration, with and without resistance training, might increase the risk of cancer through the high levels of serum IGF-1 concentration and IGF-1/ IGFBP-3 ratio in male rats.Visoke razine hormona rasta povećavaju brzinu mitoze, ali smanjuju proces apoptoze u ciljnim organima, što može uzrokovati nastanak različitih tipova raka. Stoga je glavni cilj ovoga istraživanja bio utvrditi učinak kratkotrajne primjene hormona rasta i treninga snage na histopatološke promjene tkiva štitnjače i nalaz mutacije gena BRAF-V600E u mužjaka smeđeg štakora Rattus norvegicus. Ukupno 32 štakora nasumično su podijeljena u četiri skupine koje su ovisno o primjenjenom tretmanu označene kao CS (fiziološka otopina), RS (trening snage + fiziološka otopina), GI (hormone rasta, 2 mg/kg) i RG (trening snage+hormone rasta, 2 mg/kg). Nakon osam tjedana pokusa (i.m.) uzeti su uzorci tkiva štitnjače i uzorci krvi kako bi se procijenila histopatološka svojstva, mutacija BRAF T1799A tkiva štitnjače te razine cirkulacijskog IGF-1 i IGFBP-3. Trening se sastojao od toga da se štakori penju ljestvama noseći težinu (3 seta vježbi, 5 ponavljanja). Mikroskopska procjena tkiva štitnjače nije pokazala histopatološke promjene i nije bilo mutacija u promatranoj regiji sekvencija gena BRAF. Koncentracija serumskog IGF-1 bila je znakovito manja u skupini RS nego u ostalim skupinama (P < 0,05), no u toj skupini nije bilo znakovite promjene u koncentraciji serumskog IGFBP-3. Štoviše, koncentracije serumskog IGF-1 i IGFBP-3 bile su znakovito veće u skupinama GI i RG nego u ostalim skupinama (P < 0,05). Stoga smo zaključili da bi smanjenje koncentracije serumskog IGF-1 i IGF-1/IGFBP-3 nakon treninga snage moglo smanjiti rizik od raka. Osim toga kratkotrajna primjena hormona rasta, s treningom snage kao i bez njega, mogla bi povećati rizik od raka povećavajući koncentracije serumskog IGF-1 i IGF-1/IGFBP-3 u mužjaka štakora

Genetic Diversity of Urial Population in Northeast of Iran

Habitat eradication and loss of animal species have created a new international hazard for wildlife conservation. National parks are considered as suitable places that can serve dual functions of biodiversity conservation and ecotourism. As recommended by the Food and Agriculture Organization (FAO), microsatellites have been used for animal biodiversity assessment. For this reason, Iranian urials population genetic diversity was studied by analyzing of 10 microsatellite markers in 75 skeletal muscle samples that were collected from Tandooreh National Park, Northeastern of Iran. Species of samples validated by sequencing of the control region from mtDNA. Allelic frequencies for each locus in the population and different measurements of within-breed genetic variations were computed by the POPGENE32 software. The number of alleles per locus counted from 5 to 8, with an average of 6.1. The polymorphism information content was calculated between 0.66-0.74 with the average of 0.7. Observed heterozygosity ranged from 0.223 (MaF214) to 0.776 (OarFCB128) with an average about 0.584 while the average expected heterozygosity for all studied loci was 0.785 ranging from 0.765 (BM8125) to 0.807 (MaF36). High levels of expected heterozygosity can be attributed to some factors such as low level of inbreeding, low selection pressure, and high allele number. However, findings of the present study of the high variability of the Iranian urials showed the presence of a possible ‘hot spot’ genetic diversity for wild urial population in the Northeast of Iran. In conclusion, values of genetic diversity revealed that the Iranian urial population harbor unique and appreciable reservoirs of diversity

Asymmetric growth-limiting development of the female conceptus

IntroductionSex differences in prenatal growth may contribute to sex-dependent programming effects on postnatal phenotype. MethodsWe integrated for the first time phenotypic, histomorphological, clinico-chemical, endocrine and gene expression analyses in a single species, the bovine conceptus at mid-gestation. ResultsWe demonstrate that by mid-gestation, before the onset of accelerated growth, the female conceptus displays asymmetric lower growth compared to males. Female fetuses were smaller with lower ponderal index and organ weights than males. However, their brain:body weight, brain:liver weight and heart:body weight ratios were higher than in males, indicating brain and heart ‘sparing’. The female placenta weighed less and had lower volumes of trophoblast and fetal connective tissue than the male placenta. Female umbilical cord vessel diameters were smaller, and female-specific relationships of body weight and brain:liver weight ratios with cord vessel diameters indicated that the umbilico-placental vascular system creates a growth-limiting environment where blood flow is redistributed to protect brain and heart growth. Clinico-chemical indicators of liver perfusion support this female-specific growth-limiting phenotype, while lower insulin-like growth factor 2 (IGF2) gene expression in brain and heart, and lower circulating IGF2, implicate female-specific modulation of key endocrine mediators by nutrient supply. ConclusionThis mode of female development may increase resilience to environmental perturbations in utero and contribute to sex-bias in programming outcomes including susceptibility to non-communicable diseases

Investigating the Probiotic Properties and Antimicrobial Activity of Lactic Acid Bacteria Isolated from an Iranian Fermented Dairy Product, Kashk

In the present study, kashk samples were collected from two regions of Iran, the Fars (Abadeh) and Razavi Khorasan (Kalat) provinces. Fifteen bacteria were isolated and physiological and biochemical assays were performed. After identification to the genus level, eight isolates were identified as lactic acid bacteria (LAB) and subjected to molecular identification and probiotic properties assays. The results revealed that the isolates were Enterococcus faecium KKP 3772 (KF1), Enterococcus faecium C1 (KF2), Pediococcus pentosaceus H11 (KF3), Pediococcus pentosaceus VNK-1 (KK4), Lactococcus lactis RSg (KK1), Enterococcus faecalis P190052 (KK2), Enterococcus mundtii CECT972T (KK3), and Lactiplantibacillus plantarum PM411 (KK5). Only the numbers of L. lactis RSg (KK1) and Lpb. Plantarum PM411 (KK5) decreased to below 9 Log CFU/mL after acidic conditions (pH = 3) and showed weak antibacterial activity. Enterococcus mundtii CECT972T (KK3) and E. faecium C1(KF2) were highly susceptible to bile salts, while P. pentosaceus VNK-1 (KK4) and P. pentosaceus H11 (KF3) showed the highest resistance. All of the isolates were resistant to tetracycline and sensitive to chloramphenicol and gentamicin. The antimicrobial activity of P. pentosaceus VNK-1 (KK4) and P. pentosaceus H11 (KF3) was higher than other isolates and consequently, their inhibition zones were larger. The adhesion capabilities of LAB isolates to intestinal epithelial cells were evaluated by examining the auto-aggregation factor and cell surface hydrophobicity. The highest and lowest cell surface hydrophobicity and auto-aggregation were obtained from P. pentosaceus VNK-1 (KK4) and E. mundtii CECT972T (KK3), respectively. In general, P. pentosaceus VNK-1 (KK4) and P. pentosaceus H11 (KF3) have shown better probiotic properties as compared to other isolates

Antimicrobial peptide, cLF36, affects performance and intestinal morphology, microflora, junctional proteins, and immune cells in broilers challenged with E. coli

This study investigated the effects of an antimicrobial peptide (AMP), cLF36, on growth performance and the histophysiological changes of the intestine in E. coli-challenged broiler chickens. A total number of 360 day old male chicks were randomly assigned to 4 groups of 6 replicates as follows: T1) negative control diet based on corn-soybean meal without E. coli challenge and additives; T2) positive control diet based on corn-soybean meal and challenged with E. coli without any additives; T3) positive control diet challenged with E. coli and supplemented with 20mg AMP (cLF36)/kg diet; T4) positive control diet challenged with E. coli and supplemented with 45mg antibiotic (bacitracin methylene disalicylate)/kg diet. Results showed that T3 improved growth performance and the jejunal morphology of E. coli-challenged chickens similar to those of T4. While antibiotic non-selectively decreased the population of ileal bacteria, AMP increased the population of Lactobacillus spp. and decreased harmful bacteria in the ileum of E. coli-challenged chickens. Supplementing E. coli-challenged chickens with AMP improved the gene expression of immune cells and upregulated the expression of tight junction proteins compared to other challenged groups. In conclusion, although cLF36 beneficially affected growth performance and the intestinal morphology of E. coli-challenged chickens similar to those of the antibiotic group, this AMP drastically improved the intestinal microbiome, immune cells, and junctional proteins compared to other E. coli-challenged birds, and can be nominated as an alternative for growth promoter antibiotics

KRAS-related long noncoding RNAs in human cancers

KRAS is one of the most widely prevalent proto-oncogenes in human cancers. The constitutively active KRAS oncoprotein contributes to both tumor onset and cancer development by promoting cell proliferation and anchorage-independent growth in a MAPK pathway-dependent manner. The expression of microRNAs (miRNAs) and the KRAS oncogene are known to be dysregulated in various cancers, while long noncoding RNAs (lncRNAs) can act as regulators of the miRNAs targeting KRAS oncogene in different cancers and have gradually become a focus of research in recent years. In this review article, we summarize recent advances in the research on lncRNAs that have sponging effects on KRAS-targeting miRNAs as crucial mediators of KRAS expression in different cell types and organs. A deeper understanding of lncRNA function in KRAS-driven cancers is of major fundamental importance and will provide a valuable clinical tool for the diagnosis, prognosis, and eventual treatment of cancers

Development of rapid PCR-RFLP technique for identification of sheep, cattle and goat’s species and fraud detection in Iranian commercial meat products

Identification of animal species used in commercial meat products is important with respect to economic and sanitary issues. The aim of this research was to realize ruminant species in meat products using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. The universal CB7u primers pair was used for amplifying ~195 bp fragment from a variable region of cytochrome-b mitochondrial DNA gene by polymerase chain reaction. Species differentiation was realized by digestion of the amplified ~195 bp fragments with Sse9I restriction enzyme. The results indicate that 7/7 of Kebab loghmeh, 9/10 of minced meat, 4/8 of beef burger and 2/5 samples of canned stew samples, were contaminated with one of prohibited ruminant species residual. Furthermore, the results reveal that 5/30 of samples had cross-contamination with a mixture of meat originated from various species, which was against the labelled nutrition information. Our results indicate that the PCR-RFLP technique is a powerful and reproducible test for detection and separation of ruminant species residuals in commercial meat products, especially in developing countries.Keywords: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), mitochondrial DNA, ruminant species, commercial meat products, cytochrome-b gen

Characterization of bovine (Bos taurus) imprinted genes from genomic to amino acid attributes by data mining approaches.

Genomic imprinting results in monoallelic expression of genes in mammals and flowering plants. Understanding the function of imprinted genes improves our knowledge of the regulatory processes in the genome. In this study, we have employed classification and clustering algorithms with attribute weighting to specify the unique attributes of both imprinted (monoallelic) and biallelic expressed genes. We have obtained characteristics of 22 known monoallelically expressed (imprinted) and 8 biallelic expressed genes that have been experimentally validated alongside 208 randomly selected genes in bovine (Bos taurus). Attribute weighting methods and various supervised and unsupervised algorithms in machine learning were applied. Unique characteristics were discovered and used to distinguish mono and biallelic expressed genes from each other in bovine. To obtain the accuracy of classification, 10-fold cross-validation with concerning each combination of attribute weighting (feature selection) and machine learning algorithms, was used. Our approach was able to accurately predict mono and biallelic genes using the genomics and proteomics attributes

The immunomodulatory effects of lactoferrin and its derived peptides on NF‐κB signaling pathway: A systematic review and meta‐analysis

Abstract Background Lactoferrin is a versatile protein with important modulatory functions in inflammation and immune response. This glycoprotein can bind and sequester iron and LPS, thereby intervening in certain signaling pathways and biological processes. In the present meta‐analysis, we aimed to pool experimental data regarding the immunomodulatory effects of lactoferrin and its derived peptides on the NF‐κB signaling pathway. Materials We searched PubMed, Google Scholar, and Web of Science databases and obtained all related articles published before April 2022. Finally, 25 eligible studies were selected, and their reports were analyzed. Methods We used Review Manager Version 5.2 to compute the standardized mean difference (SMD) and its 95% confidence interval. In addition, the source of heterogeneity was explored using meta‐regression and sensitivity analysis. The symmetry of the funnel plot and Egger's test were also used to evaluate publication bias utilizing Comprehensive Meta‐Analysis Version 2. Results Comparing the group of cells and animals exposed to lipopolysaccharide alone with the group that received pretreatment with lactoferrin and its derivatives, we observed significant reductions in TNF‐α, IL‐1 beta, and IL‐6 levels by 8.73 pg/mL, 2.21 pg/mL, and 3.24 pg/mL, respectively, in the second group. Additionally, IKK‐β, p‐IκB, and NF‐κB (p65) levels were significantly lower by 7.37‐fold, 15.02‐fold, and 3.88‐fold, respectively, in various cells and tissues. Conclusion Based on the results of this meta‐analysis, lactoferrin and its derived peptides can be considered potent prophylactic and therapeutic candidates against inflammation‐associated diseases by targeting the NF‐kB pathway