Molecular detection of tilapia lake virus (TiLV) genome in Nile tilapia (Oreochromis niloticus) from Lake Victoria
. Tanzania Veterinary Journal 2018
Tilapia lake virus (TiLV) is an emerging pathogen of Tilapiines associated with high mortalities of wild and farmed tilapia posing great threat to the fishery industry worldwide. The virus has been reported in Israel, Ecuador, Colombia, Thailand, Egypt, Taiwan, India and Malaysia. In this study, a reverse transcription polymerase chain reaction (RT-PCR) assay was developed and used to detect TiLV genome in Nile tilapia from Lake Victoria. Nile tilapia samples were collected from the Tanzanian (108 fish) and Ugandan (83 fish) parts of Lake Victoria in 2015 and 2016, respectively. Samples were screened for TiLV by using RT-PCR and the PCR products were sequenced. The findings show that out of the 191 fish examined, 28 had PCR products showing the presence of TiLV genome. The TiLV nucleic acids were detected in the spleen (10.99%, N=191), head kidney (7.69%, N=65), heart (3.45%, N=29) and liver (0.71%, N=140) samples while no PCR amplification was detected in the brain by the developed RT-PCR method. Generally, the findings show that the lymphoid organs, mainly comprising of the head kidney and spleen had the highest number of samples with positive nucleic acids for TiLV followed by heart samples. On the contrary, the liver and brain that have previously been shown to be target organs during acute infection either did not have or had the lowest level of TiLV nucleic acids detected in the present study. All the 28 sequences retrieved had an average length of 768 bp. A blast analysis on NCBI showed that all sequences obtained were homologous to TiLV segment-2 sequences obtained from previous outbreaks in Israel and Thailand. To our knowledge, this is the first detection of TiLV subclinical infections in Nile tilapia in Lake Victoria, a none-outbreak area.
Ammonia and CO2 enrichment of a Gracilaria cultivation pond through biofiltration of organic waste
. Aquaculture 2018
, 45 - 48. Publisher's VersionAbstract
Intensive pond cultivation of Gracilaria may achieve maximal yields by enrichment of seawater with ammonia and CO2. In the present study, we examined the use of organic waste material as a source of ammonia and inorganic carbon. A biofiltration system was constructed, consisting of several fermentation tanks and a fluidized bed reactor for the required bioconversion of organic wastes. Gracilaria conferta was cultured in a 30m2 pond from which seawater was circulated through the biofiltration system for a period of nine months. As compared to the filtered seawater used for water supply, the outlets of the fermentation tanks and the fluidized bed reactor showed significant increases in dissolved inorganic carbon and ammonia concentrations and significant decreases in oxygen concentrations and redox potentials. The most efficient organic waste compound tested had the highest C/N ratio. No significant differences were found between the Gracilaria yields of the control and biofiltration pond systems. These results might contribute a fundamental improvement in the economy of Gracilaria pond cultivation by water recycling through such a biofiltration system. Statement of relevance The system might contribute a fundamental improvement in the economy of Gracilaria pond cultivation.
Off-flavor compounds in recirculating aquaculture systems (RAS): Production and removal processes
. Aquacultural Engineering 2018
, 57 - 64. Publisher's VersionAbstract
The accumulation of geosmin and 2-methylisoborneol in culture water and fish is a common problem encountered in recirculating aquaculture systems (RAS). In these systems, like in other aquaculture systems, abatement of this problem is usually conducted by purging the fish with clean water prior to their marketing. In indoor RAS, mainly heterotrophic prokaryotes underlie the production of geosmin and MIB. While production of these off flavor compounds has been linked with the organic-rich parts of these systems, no further information on factors that promote the growth of the geosmin and MIB-producing microorganisms under these conditions is currently available. Thus far, geosmin and MIB removal from RAS has mainly been conducted by ozonation, albeit with limited success. Biodegradation of geosmin and MIB might serve as an additional method for removal of these compounds from RAS. Geosmin and MIB degradation has been detected in the latter systems, yet factors which promote the activity of geosmin and MIB degraders in these systems remain largely unknown. In the present review, the current knowledge on geosmin and MIB production and removal in RAS is presented. Emphasis is placed on the biodegradation of these off-flavor compounds, a process which has received little attention thus far.
In-ovo green light photostimulation during different embryonic stages affect somatotropic axis
. Poultry Science 2018
, 1998 - 2004. Publisher's VersionAbstract
ABSTRACT Previous studies demonstrated that in-ovo photostimulation with monochromatic green light increased the somatotropic axis expression in broilers embryos. The objective of the current study was to detect the critical period for in-ovo GL photostimulation, in order to find the optimal targeted photostimulation period during the incubation process. Three hundred thirty-six fertile broiler eggs were divided into 4 groups. The first group was incubated under dark conditions as a negative control. The second incubated under intermittent monochromatic green light using light-emitting diode (LED) lamps with an intensity of 0.1 W\m2 at shell level from d 0 of the incubation as a positive control. The third group incubated under intermittent monochromatic green light from d 10 of the incubation. The last group incubated under intermittent monochromatic green light from d 15 of the incubation. In-ovo green light photostimulation from embryonic d 0 (ED0) increased plasma growth hormone (GH), as well as hypothalamic growth hormone releasing hormone (GHRH) and liver growth hormone receptor (GHR) and insulin-like growth factor-1 (IGF-1) mRNA levels. In-ovo green light photostimulation from ED10 increased the GH plasma levels compared to the negative control group, without affecting somatotropic axis mRNA genes expressions of GHRH, GHR, and IGF-1. In-ovo green light photostimulation from ED15 caused an increase in both the plasma GH levels and the somatotropic axis mRNA genes expressions of GHRH, GHR, and IGF-1, compared to the negative control group. These results suggest that the critical period of somatotropic axis acceleration by GL photostimulation start at 15 d of incubation.
Thrombospondin-1 at the crossroads of corpus luteum fate decisions
. Reproduction 2018
The multimodular matricellular protein thrombospondin-1 (THBS1) was among the first identified endogenous antiangiogenic molecules. Recent studies have shown THBS1-mediated suppression of angiogenesis and other critical activities for corpus luteum (CL) regression. THBS1 is specifically induced by prostaglandin F2alpha in mature CL undergoing regression, whereas luteinizing signals such as luteinizing hormone and insulin reduced its expression. THBS1 interacts both synergistically and antagonistically with other essential luteal factors, such as fibroblast growth factor 2, transforming growth factor beta1, and serpin family E member 1, to promote vascular instability, apoptosis, and matrix remodeling during luteal regression. Expression of THBS1 is also downregulated by pregnancy recognition signals to maintain the CL during early pregnancy. This dynamic pattern of luteal expression, the extensive interactivity with other luteal factors, and strong antiangiogenic and proapoptotic activities indicate that THBS1 is a major determinant of CL fate.
Innate immune functions of avian intestinal epithelial cells: Response to bacterial stimuli and localization of responding cells in the developing avian digestive tract
. PLoS One 2018
Intestinal epithelial cells are multi-tasked cells that participate in digestion and absorption as well as in protection of the digestive tract. While information on the physiology and immune functions of intestinal epithelial cells in mammals is abundant, little is known of their immune function in birds and other species. Our main objectives were to study the development of anti-bacterial innate immune functions in the rapidly developing gut of the pre- and post-hatch chick and to determine the functional diversity of epithelial cells. After establishing primary intestinal epithelial cell cultures, we demonstrated their capacity to uptake and process bacteria. The response to bacterial products, LPS and LTA, induced expression of pro-inflammatory cytokine genes (IL-6, IL-18) as well as the expression of the acute phase proteins avidin, lysozyme and the secretory component derived from the polymeric immunoglobulin receptor. These proteins were then localized in gut sections, and the goblet cell was shown to store avidin, lysozyme as well as secretory component. Lysozyme staining was also located in a novel rod-shaped intestinal cell, situated at different loci along the villus, thus deviating from the classical Paneth cell in the mammal, that is restricted to crypts. Thus, in the chicken, the intestinal epithelium, and particularly goblet cells, are committed to innate immune protection. The unique role of the goblet cell in chicken intestinal immunity, as well as the unique distribution of lysozyme-positive cells highlight alternative solutions of gut protection in the bird.
Plasma Lipoprotein Particle Subclasses in Preterm Infants
. Am J Perinatol 2018
OBJECTIVE: A pilot study to determine lipoprotein classes and subclasses in premature infants and examine associations with nutritional intake, gestational age (GA), and morbidity.
STUDY DESIGN: Plasma lipoprotein particle concentrations were analyzed in a cohort of 15 premature infants in the first 5 days of life and again at 2 weeks. Breast milk samples were analyzed for fatty acid content. Associations between lipoprotein particle subclasses and GA, breast milk intake, milk fatty acid intake, and chronic lung disease (CLD) were determined.
RESULTS: At 2 weeks of age, more premature infants had higher concentrations of total very low-density lipoprotein and lower concentrations of total high-density lipoprotein (HDL) and large HDL particles (similar to profiles seen in adults and children with infectious disease, cardiometabolic disease, and diabetes). Lower total HDL, large HDL, and medium HDL and a higher small HDL:total HDL ratio at 2 weeks were each associated with CLD with GA a likely confounder. Intake of human milk C18 and C20 fatty acids was inversely correlated with plasma total LDL concentration at 2 weeks of age.
CONCLUSION: Dyslipidemia was common in extremely premature infants and was associated with CLD and with lower intake of specific long chain fatty acids.
The Effect of Iodophor Post-Milking Teat Disinfection on Iodine Content in Goat Milk
. Israel Journal of Veterinary Medicine 2018
, 14 - 22.Abstract
Iodine intake is important for thyroid function and human health. Goat milk can be an important source of iodine for human nutrition. However, data regarding the effect of iodophor post-milking teat disinfection on iodine content in goat milk is lacking. Our aim was to assess the iodine concentrations in raw milk of dairy goats and to investigate the effect of post-milking teat-dipping iodophor practice on iodine content in goat milk. Two groups of dairy goats (n=6 in each) were treated with different post-milking teat-dipping disinfection: iodine-free solution (iodine-free group) and iodine-based solution (4,000 μg/L) (iodophors group). Treatments were carried out for 19 experimental days, following a 14-day pre-experimental period, in which only iodine-free sanitizer was used for both groups. The results showed that Iodine concentrations in milk of all goats were 49 ± 23, 49, 17-86 μg/100g (mean ± SD, median, range) at days-3,-2,-1 and 45 ± 26, 42, 14-96 μg/100g (mean ± SD, median, range) at days 17, 18, 19 of treatment. Iodine concentration increased by 7 μg/100g (mean) in the iodophors group while iodine concentration decreased by 15 μg/100g by day 17-19 of treatment in the iodine free group. It was concluded that relatively high iodine concentrations were found in raw milk of dairy goats whose teats were dipped post-milking in disinfectants with or without iodine. Post-milking teat-dipping iodophor practice may increase iodine content in goat milk within an average period of 20 days. This information can help in controlling iodine content in goat milk and iodine intake in the public.
Fluorimetric Techniques for the Assessment of Sperm Membranes
. JoVE 2018
, e58622. Publisher's VersionAbstract
Standard spermiograms describing sperm quality are mostly based on the physiological and visual parameters, such as ejaculate volume and concentration, motility and progressive motility, and sperm morphology and viability. However, none of these assessments is good enough to predict the semen quality. Given that maintenance of sperm viability and fertilization potential depends on membrane integrity and intracellular functionality, evaluation of these parameters might enable a better prediction of sperm fertilization competence. Here, we describe three feasible methods to evaluate sperm quality using specific fluorescent probes combined with fluorescence microscopy or flow cytometry analyses. Analyses assessed plasma membrane integrity using 4',6-diamidino-2-phenylindole (DAPI) and propidium iodide (PI), acrosomal membrane integrity using fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA) and mitochondrial membrane integrity using 5,5',6,6'-tetra-chloro-1,1',3,3'-tetraethylbenzimidazolyl carbocyanine iodide (JC-1). Combinations of these methods are also presented. For instance, use of annexin V combined with PI fluorochromes enables assessing apoptosis and calculating the proportion of apoptotic sperm (apoptotic index). We believe that these methodologies, which are based on examining spermatozoon membranes, are very useful for the evaluation of sperm quality.
Stress-induced alterations in oocyte transcripts are further expressed in the developing blastocyst
. Molecular Reproduction and Development 2018
, 821 - 835. Publisher's VersionAbstract
The oocyte achieves its developmental competence through the lengthy process of folliculogenesis. It can therefore potentially be exposed to various stressors while enclosed in the follicle. Oocyte maturation relies mainly on maternal sources. These include nuclear, cytoplasmic, and molecular maturation, which involve DNA and RNA organization. Maternal transcripts are dominant through the first embryonic cleavages, up until embryonic genome activation. Thus, it is suggested that any perturbations during oocyte storage, in particular of the maternal transcripts, might lead to genetic and/or epigenetic changes, which might be further expressed in the developing embryo. The review discusses the effects of three representative stressors?environmental heat stress, endocrine-disrupting compounds (phthalates), and inflammatory stress (mastitis)?shown to be involved in reduced fertility. The review highlights the carryover response from the oocyte to the developing embryo; it includes intracellular and molecular disruptive mechanisms with an emphasis on maternal transcripts. The review provides insights into the oocyte?s cellular and molecular responses with an emphasis on the effects of various stressors on the maternal (nuclear and mitochondrial) transcripts and the association with embryonic development. A comparison between stressors might clarify, at least in part, a few open questions. For instance, (a) whether stress-induced alterations share the same mechanism and if so (b) whether this mechanism involves alterations of maternal transcripts; (c) whether stress-induced alterations in the maternal transcript are further expressed at the developing blastocyst stage, that is, after embryonic genome activation.
Symposium review: Reduction in oocyte developmental competence by stress is associated with alterations in mitochondrial function1
. Journal of Dairy Science 2018
, 3642 - 3654. Publisher's VersionAbstract
ABSTRACTStress can affect reproductive performance of lactating cows by targeting the ovarian pool of follicles and their enclosed oocytes. Among the documented stressors are heat stress (i.e., high temperature-humidity index) as well as environmental and food toxins. Oocytes collected during the hot season are of lower quality than those collected in the winter, expressed by reduced oocyte maturation and developmental competence. A similar pattern has been reported for oocytes exposed to endocrine-disrupting chemicals. Whereas the underlying mechanism might differ among stressors, accumulating evidence suggests that stress-induced impairment of oocyte developmental competence involves alterations in mitochondrial functioning. Within the oocyte, mitochondria are involved in ATP generation, calcium homeostasis, regulation of cytoplasmic reduction–oxidation, signal transduction, and apoptosis. Summer heat stress is strongly associated with alterations in mitochondrial distribution and alterations in mitochondria membrane potential. Heat stress impairs the expression of mitochondrion-associated genes, in particular those related to mitochondrial DNA transcription and replication and encoding oxidative phosphorylation complexes for ATP production. Reduction of ATP levels below the required threshold is suggested to compromise the progression of oocyte maturation and, subsequently, embryonic development. Another mechanism associated with mitochondrial function is the increase in reactive oxygen species (ROS), which has been documented in oocytes exposed to heat stress or environmental toxicants. Oxidative phosphorylation in mitochondria is the major source of ROS. Under physiological conditions, ROS are essential for nuclear maturation; however, disequilibrium between ROS production and antioxidative capacity might lead to DNA damage and apoptosis. The current review provides new insights into the oocyte's cellular and molecular responses to stress with an emphasis on the mitochondria. It discusses some strategies to mitigate the effects of stress on the mitochondria, such as incorporation of coenzyme Q10—a key component of the mitochondrial respiratory chain—administration of antioxidants, and injection of healthy mitochondria. Exploring the oocyte's cellular and molecular responses, in particular that of the mitochondria, might lead to the development of new strategies to mitigate the effects of various stressors on fertility.
Aflatoxin B1 impairs sperm quality and fertilization competence
. Toxicology 2018
, 42 - 50. Publisher's VersionAbstract
Aflatoxins are poisonous byproducts of the soilborne fungus Aspergillus, involved in the decomposition of plant materials. Aflatoxins can be found in various food products, such as maize, sorghum, millet, rice and wheat. AFB1 is the most toxic of these, classified as a carcinogen and mutagen for both humans and animals. AFB1 has been detected in human cord blood and placenta; however, its toxic effect on sperm is less known. The current study examines sperm responses associated with AFB1 exposure. These included acrosome integrity and function, mitochondrial polarity, DNA fragmentation, fertilization competence and early embryonic development. Spermatozoa were obtained from bull ejaculate and epididymis and capacitated in vitro for 4h with 0, 0.1, 1, 10 and 100μM AFB1. Following capacitation, acrosome reaction (AR) was induced by Ca2+ ionophore. The integrity and functionality of sperm were examined simultaneously by florescent staining. A Halosperm DNA fragmentation kit was used to evaluate DNA integrity. An in-vitro culture system was used to evaluate fertilization competence and blastocyst formation rate, using bovine oocytes. Findings indicate dose-responsive variation among compartments to AFB1 exposure. Sperm viability, expressed by integrity of the plasma membrane, was lower in sperm isolated from ejaculate or epididymis after culturing with AFB1. Exposure to AFB1 reduced the proportion of sperm from the epididymis tail undergoing acrosome reaction induced by Ca2+ ionophore. AFB1 impaired mitochondrial membrane potential (ΔYm) in sperm isolated from ejaculate and the epididymis tail. Exposing ejaculated sperm to AFB1 increased the proportion of sperm with fragmented DNA and reduced the proportion of embryos that cleaved to the 2- to 4-cell stage, 42h postfertilization, however, the proportion of embryos that developed to blastocysts, 7days postfertilization, did not differ among groups. The findings explore the harmful effects of AFB1 on sperm viability, ΔΨm and DNA integrity associated with fertility competence. We postulate that AFB1-induced fragmentation in paternal DNA might have a carryover effect on the quality of developing embryos. Further evaluation for the quality of blastocysts derived from sperm exposed to AFB1 is warranted.
The effects of replacing eggs with chicks on mesotocin, dopamine, and prolactin in the native Thai hen
. General and Comparative Endocrinology 2018
, 32 - 42. Publisher's VersionAbstract
The mesotocinergic (MTergic) and dopaminergic (DAergic) systems have been documented to play pivotal roles in maternal behaviors in native Thai chickens. In native Thai chickens, plasma prolactin (PRL) concentrations are associated with maternal behaviors, which are also controlled by the DAergic system. However, the role of MT in conjunction with the roles of DA and PRL on the neuroendocrine regulation of the transition from incubating to rearing behavior has never been studied. Therefore, the aim of this study was to investigate the association of MT, DA, and PRL during the transition from incubating to rearing behavior in native Thai hens. Using an immunohistochemistry technique, the numbers of MT-immunoreactive (-ir) and tyrosine hydroxylase-ir (TH-ir, a DA marker) neurons were compared between incubating hens (INC; n = 6) and hens for which the incubated eggs were replaced with 3 newly hatched chicks for 3 days after 6, 10, and 14 days of incubation (REC; n = 6). Plasma PRL concentrations were determined by enzyme-linked immunosorbent assay. The results revealed that the numbers of MT-ir neurons within the nucleus supraopticus, pars ventralis (SOv), nucleus preopticus medialis (POM), and nucleus paraventricularis magnocellularis (PVN) increased in the REC hens when compared with those of the INC hens at 3 different time points (at days 9, 13, and 17). On the other hand, the number of TH-ir neurons in the nucleus intramedialis (nI) decreased in the REC13 and REC17 hens when compared with those of the INC hens. However, the number of TH-ir neurons in the nucleus mamillaris lateralis (ML) only decreased in the REC13 hens when compared with the INC13 hens. The decrease in the numbers of TH-ir neurons within the nI and ML is associated with the decrease in the levels of plasma PRL. This study suggests that the presence of either eggs or chicks is the key factor regulating the MTergic system within the SOv, POM, and PVN and the DAergic system within the nI and ML during the transition from incubating to rearing behavior in native Thai chickens. The results further indicate that these two systems play pivotal roles in the transition from incubating to rearing behavior in this equatorial species.
Hormonal levels of estradiol, testosterone, and progesterone at entry into lay of year 1980 vs. 2000 broiler breeder females under fast and slow release from feed restriction
. Poultry Science 2018
, 3728 - 3735. Publisher's VersionAbstract
In the mid-1960s egg production, fertility, and hatchability of broiler breeder females dropped precipitously. Due to disrupted follicle hierarchies and development of the erratic oviposition and defective eggs (EODES) syndrome. EODES was controlled by restricting feed. In the 1990s, another set of problems arose at entry of broiler breeders into lay and characterized by high mortality followed by lower peak lay and reduction in egg and chick production. These problems are induced by even slight over-feeding, and hence we termed it the “Over Feeding Complex” (OFC). We have speculated that OFC is a quasi-EODES condition, induced by the intense selection for increased breast proportion. To test this, we compared, under fast (FF) and slow (SF) release from feed restriction, body composition and reproductive performance of a broiler breeder from year 1980 (B1980) and kept without selection for performance traits since then, to a line hatched in 2000 (B2000). During the first 16 d of lay, feeding treatment had little effect on egg mass or Laying % for the B1980 birds, while for the B2000 birds, SF treatment resulted in significantly greater egg mass and Laying % compared to FF, showing that the OFC indeed manifested in this experiment. However, contrary to hypothesis, follicle hierarchies were normal for both lines under both feeding treatments. To gain further insight into the OFC syndrome, we here report levels of estradiol, testosterone, and progesterone for these line and treatment groups in the time period leading up to and into lay. A significant line × feeding treatment interaction effect was found for estradiol and testosterone, to a lesser extent for progesterone. For all 3 hormones, for B1980 levels 2 to 3 wk post entry into lay were similar and intermediate under FF and SF, but differed significantly for B2000, being much greater under SF than under FF. Thus, the hormonal effects were parallel and may explain the egg mass and Laying % effects of FF and SF in the 2 genetic types.
In-ovo green light photostimulation during different embryonic stages affect somatotropic axis
. Poultry Science 2018
, 1998 - 2004. Publisher's VersionAbstract
Previous studies demonstrated that in-ovo photostimulation with monochromatic green light increased the somatotropic axis expression in broilers embryos. The objective of the current study was to detect the critical period for in-ovo GL photostimulation, in order to find the optimal targeted photostimulation period during the incubation process. Three hundred thirty-six fertile broiler eggs were divided into 4 groups. The first group was incubated under dark conditions as a negative control. The second incubated under intermittent monochromatic green light using light-emitting diode (LED) lamps with an intensity of 0.1 W\m2 at shell level from d 0 of the incubation as a positive control. The third group incubated under intermittent monochromatic green light from d 10 of the incubation. The last group incubated under intermittent monochromatic green light from d 15 of the incubation. In-ovo green light photostimulation from embryonic d 0 (ED0) increased plasma growth hormone (GH), as well as hypothalamic growth hormone releasing hormone (GHRH) and liver growth hormone receptor (GHR) and insulin-like growth factor-1 (IGF-1) mRNA levels. In-ovo green light photostimulation from ED10 increased the GH plasma levels compared to the negative control group, without affecting somatotropic axis mRNA genes expressions of GHRH, GHR, and IGF-1. In-ovo green light photostimulation from ED15 caused an increase in both the plasma GH levels and the somatotropic axis mRNA genes expressions of GHRH, GHR, and IGF-1, compared to the negative control group. These results suggest that the critical period of somatotropic axis acceleration by GL photostimulation start at 15 d of incubation.
Mammary core clock gene expression is impacted by photoperiod exposure during the dry period in goats
. Journal of Applied Animal Research 2018
, 1214 - 1219. Publisher's VersionAbstract
ABSTRACTShort-day photoperiod (SDPP) during the dry period increases milk production compared to long-day photoperiod (LDPP) in goats. Photoperiod information is sent to the master clock in the suprachiasmatic nuclei (SCN), which send temporal information to peripheral clocks located in every tissue of the body. We hypothesized photoperiod effects on milk production are mediated in part by changes in mammary clocks. Our objective was to determine the effect of photoperiod manipulation during the dry period in goats on core clock genes expression in mammary gland. Multiparous goats (n?=?6) were blocked at dry off into two treatments: LDPP and SDPP. Serial mammary biopsies were taken over a 24?h period during three weeks prepartum. Total RNA was isolated, and q-PCR analysis of the core clock genes CLOCK, ARNTL, PER1, CRY1, and CRY2 found exposure to LDPP significantly increased ARNTL (P?
Low Iodine Intake from Dairy Foods Despite High Milk Iodine Content in Israel
. Thyroid 2018
, 1042 - 1051. Publisher's VersionAbstract
Background: Milk is a major source of iodine in human nutrition. Because both iodine content and the consumption of milk and dairy vary widely over time and populations, their contribution to iodine intake must be evaluated regularly. A recent national iodine survey found Israel's population to be mildly iodine deficient, possibly due to unmonitored changes in the food content of dietary iodine. Accounting for dairy iodine content can help guide efforts to prevent iodine deficiency. Objectives: This study aimed to determine the iodine concentration of dairy products typically consumed in the Israeli diet, and to estimate iodine intake from dairy products among Israeli adults. Methods: Iodine was analyzed in 33 selected dairy products that account for 89% of the total population's dairy intake according to the ?MABAT? Israeli National Health and Nutrition survey. Based on these data, the distribution of iodine intake from milk, dairy, and dairy-based foods in the adult population was calculated. Results: Israeli milk is rich in iodine, with a mean concentration of 22??g/100?g. However, due to low dairy consumption, the mean iodine intake from milk and dairy was only 34??g/day (median 23??g/day; range: 0?337??g/day) or 22% of the recommended daily allowance. Self-reported intake among poor, male, and Arab subgroups was even lower. Conclusions: Because Israeli milk and dairy products are iodine rich, their contribution to the population's iodine intake would increase if they were consumed in greater amounts, particularly by high-risk groups. Dairy's potential contribution to iodine nutrition should be considered in recommendations for dairy consumption and iodine prophylaxis.Background: Milk is a major source of iodine in human nutrition. Because both iodine content and the consumption of milk and dairy vary widely over time and populations, their contribution to iodine intake must be evaluated regularly. A recent national iodine survey found Israel's population to be mildly iodine deficient, possibly due to unmonitored changes in the food content of dietary iodine. Accounting for dairy iodine content can help guide efforts to prevent iodine deficiency. Objectives: This study aimed to determine the iodine concentration of dairy products typically consumed in the Israeli diet, and to estimate iodine intake from dairy products among Israeli adults. Methods: Iodine was analyzed in 33 selected dairy products that account for 89% of the total population's dairy intake according to the ?MABAT? Israeli National Health and Nutrition survey. Based on these data, the distribution of iodine intake from milk, dairy, and dairy-based foods in the adult population was calculated. Results: Israeli milk is rich in iodine, with a mean concentration of 22??g/100?g. However, due to low dairy consumption, the mean iodine intake from milk and dairy was only 34??g/day (median 23??g/day; range: 0?337??g/day) or 22% of the recommended daily allowance. Self-reported intake among poor, male, and Arab subgroups was even lower. Conclusions: Because Israeli milk and dairy products are iodine rich, their contribution to the population's iodine intake would increase if they were consumed in greater amounts, particularly by high-risk groups. Dairy's potential contribution to iodine nutrition should be considered in recommendations for dairy consumption and iodine prophylaxis.
The cAMP-EPAC Pathway Mediates PGE2-Induced FGF2 in Bovine Granulosa Cells
. Endocrinologyendo 2018
, 3482 - 3491. Publisher's VersionAbstract
During the periovulatory period, the profile of fibroblast growth factor 2 (FGF2) coincides with elevated prostaglandin E2 (PGE2) levels. We investigated whether PGE2 can directly stimulate FGF2 production in bovine granulosa cells and, if so, which prostaglandin E2 receptor (PTGER) type and signaling cascades are involved. PGE2 temporally stimulated FGF2. Accordingly, endoperoxide-synthase2–silenced cells, exhibiting low endogenous PGE2 levels, had reduced FGF2. Furthermore, elevation of viable granulosa cell numbers by PGE2 was abolished with FGF2 receptor 1 inhibitor, suggesting that FGF2 mediates this action of PGE2. Epiregulin (EREG), a known PGE2-inducible gene, was studied alongside FGF2. PTGER2 agonist elevated cAMP as well as FGF2 and EREG levels. However, a marked difference between cAMP-induced downstream signaling was observed for FGF2 and EREG. Whereas FGF2 upregulated by PGE2, PTGER2 agonist, or forskolin was unaffected by the protein kinase A (PKA) inhibitor H89, EREG was significantly inhibited. FGF2 was dose-dependently stimulated by the exchange protein directly activated by cAMP (EPAC) activator; a similar induction was observed for EREG. However, forskolin-stimulated FGF2, but not EREG, was inhibited in EPAC1-silenced cells. These findings ascribe a novel autocrine role for PGE2, namely, elevating FGF2 production in granulosa cells. This study also reveals that cAMP-activated EPAC1, rather than PKA, mediates the effect of PGE2/PTGER2 on the expression of FGF2. Stimulation of EREG by PGE2 is also mediated by PTGER2 but, in contrast to FGF2, EREG was found to be PKA sensitive. PGE2-stimulated FGF2 can act to maintain granulosa cell survival; it can also act on ovarian endothelial cells to promote angiogenesis.