• Development and Reproduction
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• v.26 no.2
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• pp.49-58
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• 2022

The differentiation and development of preadipocyte into mature adipocyte are regulated by transcription factors, such as CCAAT enhancer binding protein (Cebp) gene family and sterol regulatory element binding transcription factor 1 (Srebp1). Steroid hormones give influences on the development and function of adipocyte. The present research examined expression patterns of CCAAT enhancer binding protein alpha (Cebpa), CCAAT enhancer binding protein beta (Cebpb), CCAAT enhancer binding protein gamma (Cebpg), sterol regulatory element binding transcription factor 1 (Srebp1), androgen receptor (Ar), and estrogen receptors (Esr) among different epididymal fat parts during postnatal period by quantitative real-time polymerase chain reaction. In the distal epididymal fat, expression of Cebpa, Cebpb, Cebpg, Srebp1, Ar, and Esr2 was increased until 12 months of age, while expression of Esr1 was decreased at 5 months of age and was not detectable after 8 months of age. In the proximal epididymal fat, transcript levels of Cebps and Srebp1 were increased at 8 months of age, followed by decreases of Cebpb and Cebpg transcript levels at 12 months of age. An additional increase of Srebp1 expression was observed at 12 months of age. Expression of Ar and Esr2 were increased until 8 months of age, followed by a drop of Ar expression level at 12 months of age. Expression pattern of Esr1 was similar to that in the distal epididymal fat. In the tail epididymal fat, expression of Cebpa, Cebpg, Srebp1, Ar, and Esr2 was increased with age. Esr1 was not detectable at all. The highest level of Cebpb was observed at 8 months of age. These data suggest the possibility of developmental and functional differentiation among the epididymal fat parts.

• Toxicological Research
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• v.13 no.1_2
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• pp.175-182
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• 1997

LBD-001, a recombinant human interferon $\gamma$ produced by genetically engineered yeast as a host system, was intravenously administered to pregnant female rats (Sprague-Dawley) from day 17 of gestation to day 21 of lactation at dose levels.of $0.35 \times 10^6$, $0.69 \times 10^6$, and $1.38 \times 10^6$ I.U./kg/day. In vasopressin-treated group, vasopressin (5 I.U./kg/day) was intravenously injected only for 5 days of perinatal period. (1) No signicant changes by the treatment of LBD-001 were observed in the body weights, food and water consumption, feeding and nurshing behaviors, and the weights of main organs of mother rats. In vasopressin-treated group, no significant changes were observed except the decrease in the food consumption on day 18 of gestation and one case of abnormal offspring with bleeding spots on the skin. (2) No significant changes in the body weights, survival rates, locomotor activity, emotional development. and the motor coordination of offsprings (F1) by the treatment of LBD-001 were observed except the fact that increase of ambulation in the female offsprings of LBD-001 ($0.69 \times 10^6$ or $1.38 \times 10^6$ I.U./kg/day)-treated groups and the increase of rearing in the males of LBD-($1.38 \times 10^6$ I.U./kg/day)-treated group, and the increase of the weight of liver and ovaries in the female offsprings in the LBD-001 ($1.38 \times 10^6$ I.U./kg/day)-treated group were observed. Altogether, the results show that LBD-001 at the dose of $1.38 \times 10^6$ I.U./kg/day or less does not significantly affect the mother rats and their offsprings (F1) except the minor influences when treated during the perinatal and postnatal period.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.2
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• pp.137-142
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• 2005

To analyze the developmental changes in soma diameters of digastric motoneurons, wheat-germ agglutinin conjugated horseradish peroxidase (WGA-HRP) was injected into the digastric muscle and visualized the retrogradely HRP-labeled motoneurons through tungstate/tetramethylbenzidine (TMB) and following diaminobenzidine (DAB) reactions. The results obtained from Sprague-Dawley rats at postnatal days 1 (P1), 10 (P10) and 30 (P30) indicated as follows: firstly, soma diameters of digastric motoneurons showed unimodal distribution in all postnatal days examined; secondly, the period of P1 to P10 (period 1) showed about 2 times faster growth rate than that of P10 to P30 (period 2); thirdly, the smallest soma examined in each postnatal day exhibited slower growth rate with that of the largest one (increase ratio in soma diameters from P1 to P30, smallest vs. largest = 1.62 : 1.93); Finally, relative growth rates a day showed again that period 1 had faster growth rate than that of period 2. Consequently, developmental changes in soma diameters of digastric motoneurons resulted in very different growth rates between both periods. This implies that the growth of the soma is almost completing within P10 and thereafter growing slowly. The period 1 and 2 are corresponding to sucking and sucking/masticatory period, respectively. Therefore present study providing morphological changes in soma diameters of digastric motoneurons suggests that both periods and their different growth rates of the motoneurons in each period may closely be related with each other.

• Journal of Animal Science and Technology
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• v.50 no.1
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• pp.45-56
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• 2008

In the present study, real-time PCR was performed to evaluated expression of several isoforms of monocarboxylate transporters(MCTs) and two known MCT regulatory proteins, basigin (Bsg) and embigin, in the epididymis of the male reproductive tract during postnatal development. In addition, ERα�-mediated regulation of MCT1 expression in the epididymis was determined with estrogen receptor(ER) α� knockout(α�ERKO) mice by immunohistochemistry. Results from the current study demonstrated differential expression of MCT isoform(MCT 1, 2, 3, 4, and 8), Bsg, and embigin mRNAs in rat epididymis according to postnatal age and epididymal region. In addition, immunohistochemical study of MCT1 revealed the limited localization of MCT1 at apical area of corpus and caudal epididymis. The present study also showed that expression of MCT1 was not directly regulated by ERα�. The findings from the current study suggest that MCTs would involve in establishing adequate microenvironment for sperm maturation and storage in the epididymis, eventually leading to maintenance of male fertility.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7613-7618
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• 2015

Childhood acute lymphoblastic leukemia (ALL) is one of the most common hematologic malignancies which accounts for one fourth of all childhood cancer cases. Exposure to environmental factors around the time of conception or pregnancy can increase the risk of ALL in the offspring. This study aimed to evaluate the influence of prenatal and postnatal exposure to high voltage power lines on the incidence of childhood ALL. It also examines the role of various factors such as environmental factors and alpha-amylase as a marker in the development of leukemia.This cross-sectional case control study was carried out on 22 cases and 100 controls who born and lived in low socioeconomic families in Tehran and were hospitalized for therapeutic purposes in different hospitals ofrom 2013-2014. With regard to the underlying risk factors; familial history and parental factors were detected as risk factors of ALL but in this age, socioeonomic and zonal matched case control study, prenatal and childhood exposure to high voltage power lines was considered as the most important environmental risk factor (p=0.006, OR=3.651, CI 95% 1.692-7.878). As the population study was from low socioeconomic state, use of mobiles, computers and microwaves was negligible. Moreover prenatal and postnatal exposure to all indoor electrically charged objects were not detected as significant environmental factors in the present study. This work defined the risk of environmental especially continuous pre and postnatal exposure to high voltage power lines and living in pollutant regions through the parents or children as well as the previously described risk factors of ALL for the first time in low socioeconomic status Iranian population.

• Neonatal Medicine
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• v.28 no.2
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• pp.65-71
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• 2021

Purpose: We investigated whether consecutive levels of new emerging renal biomarkers, including serum cystatin C (CysC) and urinary neutrophil gelatinase-associated lipocalin (NGAL)/creatinine (Cr) ratio, were affected by postconceptional age in very-low-birth-weight (VLBW) infants. Methods: Repeatedly measured samples for each infant were divided into four groups according to postnatal age: at birth (stage I), 3 to 7 days postnatally (stage II), 8 to 28 days postnatally (stage III), and >28 days postnatally (stage IV). The association between renal biomarkers and postconceptional age was assessed using Pearson's correlation coefficient, and the mean values of renal biomarkers in the four stages were compared using repeated-measures analysis of variance. Results: For samples measured at birth, serum CysC (r=-0.358, P=0.032) and urinary NGAL/Cr ratio (r=-0.522, P=0.001) were negatively correlated with gestational age, whereas serum Cr (r=0.148, P=0.390) was not. In addition, for all samples measured, serum CysC (r=-0.209, P=0.012), urinary NGAL/Cr ratio (r=-0.536, P<0.001), and serum Cr (r=-0.311, P<0.001) were negatively correlated with postconceptional age. Compared with the mean values of the postnatal age-specific stages, serum CysC showed no significant differences in any of the four stages. However, the urinary NGAL/Cr ratio in stage IV was significantly different from those in stages I to III. Conclusion: Although urinary NGAL/Cr ratio and serum CysC were negatively correlated with postconceptional age considering renal development, serum CysC showed no significant differences in any of the four postnatal age-specific stages. Urinary NGAL/Cr ratio at >28 days postnatally seems to be more affected by postconceptional age than serum CysC in VLBW infants.

• Journal of Animal Reproduction and Biotechnology
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• v.35 no.4
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• pp.289-296
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• 2020

Spermatogonial stem cells are self-renewal and differentiate into sperm in post-pubertal mammals. There exists a balance between the self-renewal and differentiation in the testes. Spermatogonial stem cells make up only 0.03% of testicular cells in adult mice. These cells maintain sperm production by differentiating after puberty. Therefore, analyzing the expression of genes associated with spermatogenesis is critical for understanding differentiation. The present study aimed to establish the postnatal period of cells in relation to spermatogenesis. To study the expression of differentiated and undifferentiated marker genes in enriched spermatogonial stem cells, in vitro culture was performed and cells from pup (6-8-day-old) and adult (4-months-old) testicular tissues were isolated. As a result, undifferentiated genes, Pax7, Plzf, GFRa1, Etv5 and Bcl6b, were highly increased in cultured spermaotogonial stem cells compared with pup and adult testicular cells. On the other hands, differentiated gene, c-kit was highly increased in adult testicular cells, Also Stra8 gene was highly increased in pup and adult testicular cells. This study provides a better understanding of spermatogenesis-associated gene expression during postnatal periods.

• Applied Microscopy
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• v.29 no.4
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• pp.479-491
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• 1999

This study was performed to investigate the distribution and differentiation of choline acetyltransferase (ChAT)-immunoreactive cells in the basal nucleus of Meynert of the postnatal and adult rat forebrains, utilizing techniques of immunocytochemistry. According to the cell shape and the ratio of long axis vs short axis of cell soma, the ChAT-immunoreactive nerve cells in the basal nucleus of Meynert of the adult rat were classified into six types. In the adult rat, the frequency distributions (FD) of round, oval, elongated, fusiform, triangular and polygonal cells were 9.4%, 35.5%, 32.1%, 5.9%, 9.1% and 8.0%, respectively. The FD of oval and round nerve cells on the postnatal day (PND) 14 were observed to be 18.7% and 51.5%, respectively. Those were shown to be progressively decreased during developmental process to the adult. Also, those of elongated and triangular nerve cells on the PND 21 were observed to be 30.4% and 10.1%, respectively. Those were shown to be same phenomenon a,1 those in the round and oval cells. Meanwhile, those of the triangular and polygonal nerve cells were progressively increased from the early postnatal stage to the adult. The total mean volumes of ChAT-immunoreactive cell somata in the PND 7 rat were the lowest $(1,083{\mu}m^3)$ and those in the PND 21 rat were shown to be the highest $(5,045{\mu}m^3)$. But in the adult, those were decreased to $(2,731{\mu}m^3)$. Those in the PND 21 rat were shown to be about 84.7% larger than those in the adult. On the electron micrography, the cell organelles such as ribosomes, polysomes, rough endoplasmic reticula (RER) and mitochondria were well developed in the PND 21 rat forebrains, but Golgi complexes were shown to be proliferating phase. Especially, ribosomes, polysomes and RER were immunoreactive in the tissues treated with 0.05% triton X-100. According to the observations in the present study, it is considered that the ChAT-immunoreactive nerve cells in the basal nucleus of Meynert of the rat forebrains are differentiated throughout the following processes of changes during the postnatal development: 1) increase of cell soma volumes with the differentiation of tell organelles and neurites, 2) increase in the FD of differentiated tell types and 3) cell schrinkage without cell loss. The ribosomes, polysomes and RER are considered to be closely related to the intracellular localization and biosynthesis of the ChAT but not Colgi complex.

• Korean Journal of Agricultural Science
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• v.43 no.1
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• pp.72-79
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• 2016

It has long been known that nutritional and environmental influences during the early developmental period affect the biological mechanisms which determine animal metabolism. This phenomenon, termed 'metabolic imprinting', can cause subtle but long-lasting responses to prenatal and postnatal nutrition and even be passed onto the next generation. A large amount of research data shows that nutrient availability, in terms of quantity as well as quality, during the early developing stages can decrease the number of newborn piglets and their body weight and increase their susceptibility to death before weaning. However, investigation of potential mechanisms of 'the metabolic imprinting' effect have been scant. Therefore, it remains unknown which factors are responsible for embryonic and early postnatal nutrition and which factors are major determinants of body weight and number of new born piglets. Intrauterine undernutrition, for example, was studied using a rat model providing dams 50% restricted nutrients during pregnancy and the results showed significant decreases in birth weight of newborns. This response may be a characteristic of a subset of modulations in embryonic development which is caused by the metabolic imprinting. Underlying mechanisms of intrauterine undernutrition and growth retardation can be explained in part by epigenetics. Epigenetics modulate animal phenotypes without changes in DNA sequences. Epigenetic modifications include DNA methylation, chromatin modification and small non-coding RNA-associated gene silencing. Precise mechanisms must be identified at the morphologic, cellular, and molecular levels by using interdisciplinary nutrigenomics approaches to increase pig production. Experimental approaches for explaining these potential mechanisms will be discussed in this review.

• Toxicological Research
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• v.3 no.1
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• pp.45-53
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• 1987

A teratogenicity study was carried out on Sprague-Dawley rats which have been given the intravenously or intraperitonealy injections of rHuIFN-${\alpha}$A, an available therapeutic agent, at dose levels of $1{\times}10^5$, $4{\times}10^5$ and $1.2{\times}10^6$ I.U/kg/day for a period of 11 days from day 7 to day 17 of gestation. Two-thirds of the pregnant females in each group were sacrificed on day 20 of gestation and their fetuses were examined. The remaining dams were allowed to litter naturally, and the postnatal development of the off springs was observed. No changes were observed in all aspects of parameters between the treated and the control dams. The incidence of external, internal, and skeletal anomalies were not significantly increased in the fetuses of any treated groups. The rHuIFN-${\alpha}A$ caused no effects on parturition, lactation, and postnatal growth.