37 research outputs found
Effect of transient postpubertal hypo- and hyperthyroidism on reproductive parameters of Iranian broiler breeder hens
One hundred and thirty two 26-week-old broiler breeder hens were randomly assigned into one of three treatments as control, hypothyroid (HYPO; propylthiouracil (PTU)-treated) or hyperthyroid (HYPER;thyroxine (T4)-treated) group. PTU and T4 were administered between weeks 30 and 33 of age. Blood sampling was started at week 29, and repeated every week until week 35, coinciding with weekly bodyweighing. Using ELISA, plasma levels of T3, T4 and estradiol were assayed. Egg number, fertility, hatchability, grading of day-old chicks and embryonic developmental stage of unhatched eggs weredetermined for individual artificially inseminated hen. Effects of PTU and T4 treatment on plasma T4 levels were significant (P 0.05). In conclusion, among the different reproductive parameters in this study, hatchability and weekly egg production werethe most responsive parameters to decreased or increased plasma thyroid hormone levels, respectively
Effect of glucose, lactate and pyruvate concentrations on in vitro growth of goat granulosa cell
Carbohydrates are among the most influential of the numerous components of culture medium that affect metabolism and developmental potential. Glucose, lactate and pyruvate are required for the growth of oocytes and other follicular cells in vitro. The aim of this study was to determine the effects of different concentrations of glucose, lactate and pyruvate on promoting DNA synthesis of granulosa cells in a serum-free medium. Effects of glucose (0.75, 1.5 or 3 mM), pyruvate (0.1 or 0.33 mM) and Llactate (3, 6 or 12 mM) concentrations in the maturation medium on the relative granulosa cell growth during metaphase II (MII) were examined in a 3 × 2 × 3 factorial design. The greatest relative granulosa cell growth response (p<0.05) was observed in the presence of 1.5 mM glucose and 0.33 mM pyruvate or in 6 mM lactate and 0.33 mM pyruvate. Increasing pyruvate concentrations from 0.1 to 0.33 mM resulted in an increase in DNA synthesis in granulosa cells. In conclusion, the results of this study showed that increasing glucose and pyruvate concentrations in the maturation medium increased the growth of goat granulosa cells.Key word: Energy substrate, granulosa cell growth, methyl-3H-thymidine, goat
Autoimmune and autoinflammatory mechanisms in uveitis
The eye, as currently viewed, is neither immunologically ignorant nor sequestered from the systemic environment. The eye utilises distinct immunoregulatory mechanisms to preserve tissue and cellular function in the face of immune-mediated insult; clinically, inflammation following such an insult is termed uveitis. The intra-ocular inflammation in uveitis may be clinically obvious as a result of infection (e.g. toxoplasma, herpes), but in the main infection, if any, remains covert. We now recognise that healthy tissues including the retina have regulatory mechanisms imparted by control of myeloid cells through receptors (e.g. CD200R) and soluble inhibitory factors (e.g. alpha-MSH), regulation of the blood retinal barrier, and active immune surveillance. Once homoeostasis has been disrupted and inflammation ensues, the mechanisms to regulate inflammation, including T cell apoptosis, generation of Treg cells, and myeloid cell suppression in situ, are less successful. Why inflammation becomes persistent remains unknown, but extrapolating from animal models, possibilities include differential trafficking of T cells from the retina, residency of CD8(+) T cells, and alterations of myeloid cell phenotype and function. Translating lessons learned from animal models to humans has been helped by system biology approaches and informatics, which suggest that diseased animals and people share similar changes in T cell phenotypes and monocyte function to date. Together the data infer a possible cryptic infectious drive in uveitis that unlocks and drives persistent autoimmune responses, or promotes further innate immune responses. Thus there may be many mechanisms in common with those observed in autoinflammatory disorders
Doyne lecture 2016:intraocular health and the many faces of inflammation
Dogma for reasons of immune privilege including sequestration (sic) of ocular antigen, lack of lymphatic and immune competent cells in the vital tissues of the eye has long evaporated. Maintaining tissue and cellular health to preserve vision requires active immune responses to prevent damage and respond to danger. A priori the eye must contain immune competent cells, undergo immune surveillance to ensure homoeostasis as well as an ability to promote inflammation. By interrogating immune responses in non-infectious uveitis and compare with age-related macular degeneration (AMD), new concepts of intraocular immune health emerge. The role of macrophage polarisation in the two disorders is a tractable start. TNF-alpha regulation of macrophage responses in uveitis has a pivotal role, supported via experimental evidence and validated by recent trial data. Contrast this with the slow, insidious degeneration in atrophic AMD or in neovasular AMD, with the compelling genetic association with innate immunity and complement, highlights an ability to attenuate pathogenic immune responses and despite known inflammasome activation. Yolk sac-derived microglia maintains tissue immune health. The result of immune cell activation is environmentally dependent, for example, on retinal cell bioenergetics status, autophagy and oxidative stress, and alterations that skew interaction between macrophages and retinal pigment epithelium (RPE). For example, dead RPE eliciting macrophage VEGF secretion but exogenous IL-4 liberates an anti-angiogenic macrophage sFLT-1 response. Impaired autophagy or oxidative stress drives inflammasome activation, increases cytotoxicity, and accentuation of neovascular responses, yet exogenous inflammasome-derived cytokines, such as IL-18 and IL-33, attenuate responses
C9orf72-mediated ALS and FTD: multiple pathways to disease
The discovery that repeat expansions in the C9orf72 gene are a frequent cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) has revolutionized our understanding of these diseases. Substantial headway has been made in characterizing C9orf72-mediated disease and unravelling its underlying aetiopathogenesis. Three main disease mechanisms have been proposed: loss of function of the C9orf72 protein and toxic gain of function from C9orf72 repeat RNA or from dipeptide repeat proteins produced by repeat-associated non-ATG translation. Several downstream processes across a range of cellular functions have also been implicated. In this article, we review the pathological and mechanistic features of C9orf72-associated FTD and ALS (collectively termed C9FTD/ALS), the model systems used to study these conditions, and the probable initiators of downstream disease mechanisms. We suggest that a combination of upstream mechanisms involving both loss and gain of function and downstream cellular pathways involving both cell-autonomous and non-cell-autonomous effects contributes to disease progression
Effect of testosterone and growth hormone injection before puberty on follicles size, rate of egg production and egg characteristics of the Mazandaran Native breeder hens
Egg shell quality and egg internal quality are of major importance to the egg industry worldwide. This experiment was conducted to evaluate the effect of testosterone and growth hormone (hGH) on egg production and characteristics. The aim of this trial is to test this hypothesis that one injection of these two hormones before puberty has any effects on egg production of Mazandaran native breeder hens. Two hundred native pullet used in a completely randomized design with 4 treatments, 5 replicates and 10 hens in each box. Hens were fed on common diet and hormones injected subcutaneously based on body weight (BW). The four treatments were: 1) injection of hGH (100 ìg/kg BW), 2) injection oftestosterone (500 ìg/kg BW), 3) injection of hGH (100 ìg/kg BW) + injection of testosterone (500 ìg/kg BW) and 4) injection of 100 ìl distilled water (control). Injection was before 5% oviposition of flock (flock puberty). Egg production and characteristics were determined. Treatments affected ovary weight, small white, large white and small yellow follicles and some egg parameters. GH and testosterone can alter follicles size in ovary, and it is concluded that GH+testosterone injection is more effective on small and large follicles
Effect of Diazinon on pituitary-gonadal axis and histological alteration of seminferous tubules in adult rat testis
Background and Objective: Diazinon is an organophosphate insecticide. , which inhibits the enzyme acetylcholinesterase. This study was done to evaluate the effect of Diazinon on pituitary-gonadal axis and histological alteration of seminferous tubules in adult rat testis. Methods: In this experimental study, 40 adult male Wistar rats were randomly allocated into five groups including control, sham and experimental 1, 2 and 3. Animals in experimental group 1, 2 and 3 were received 50, 100 and 150 mg/kg/bw of diazinon for 28 days, orally, respectively. Animals in control group did not receive any substance. Animals in sham group were received an equivalent amount of normal saline. The animals were euthanized after 28 days and a blood sample was collected via heart puncture and testes were removed for histological studies. Results: Diazinon significantly reduced serum testosterone concentration, sertoli cell, leydig cell count, primary spermatocyte and spermatid (P<0.05). Diazinon had no significant effect on the body and testis weight in the experimental groups compared to controls. Conclusion: Diazinon reduces the concentration of testosterone and cells in seminferous tubule in adult rat
Study of BMP-15 gene polymorphism in Iranian goats
Different mutations in the bone morphogenetic protein-15 (BMP-15) and the Growth Differentiation Factor-9 (GDF-9) genes have increased ovulation rate and infertility in a dosage-sensitive manner insheep. To test the polymorphisms of genes in goat, which have been demonstrated as major genes of fecundity in sheep, the genetic polymorphism of FecXB and FecXG loci in BMP-15 gene were studied in109 Iranian native goats. Blood samples were collected in EDTA coated tubes from Jugular vein and genomic DNA was extracted from whole blood samples. Single nucleotide polymorphism of FecXB and FecXG loci in BMP-15 gene were determined using PCR-RFLP technique. There was no evidence of mutation in FecXB and FecXG in these goats, all of which were monomorph for exon 2 BMP-15 gene
AMD-Associated HTRA1 Variants Do Not Influence TGF-beta Signaling in Microglia
Genetic variants of high-temperature requirement A serine peptidase 1 (HTRA1) and age-related maculopathy susceptibility 2 (ARMS2) are associated with age-related macular degeneration (AMD). One HTRA1 single nucleotide polymorphism (SNP) is situated in the promotor region (rs11200638) resulting in increased expression, while two synonymous SNPs are located in exon 1 (rs1049331:C > T, rs2293870:G > T). HtrA1 is known to inhibit transforming growth factor-beta (TGF-beta) signaling, a pathway regulating quiescence of microglia, the resident immune cells of the brain and retina. Microglia-mediated immune responses contribute to AMD pathogenesis. It is currently unclear whether AMD-associated HTRA1 variants influence TGF-beta signaling and microglia phenotypes. Here, we show that an HtrA1 isoform carrying AMD-associated SNPs in exon 1 exhibits increased proteolytic activity. However, when incubating TGF-beta-treated reactive microglia with HtrA1 protein variants, neither the wildtype nor the SNP-associated isoforms changed microglia activation in vitro