ABSTRACT
Objective: Degeneration of dopaminergic neurons in the substantia nigra of the brain stem is the main pathological aspect of Parkinson's disease [PD]. 17 beta-estradiol [E2] has neuroprotective effects on substantia nigra, however, the underlined mechanism is not well-known. In this study, we evaluated the neuroprotective effects of E2 in the ovariectomized 6-hydroxydopamine- [6-OHDA] rat model of PD
Materials and Methods: In this experimental study, all animals were ovariectomized to avoid any further bias in E2 levels and then these ovariectomized rats were randomly assigned into three experimental groups [10 rats in each group]: ovariectomized control group [OCG], ovariectomized degeneration group receiving 25 µg of 6-OHDA into the left corpus striatum [ODG], and ovariectomized E2 pretreatment group pretreated with 0.1 mgkg-1of 17 beta-estradiol for three days prior to the destruction of corpus striatum with 6-OHDA [OE2PTG]. The apomorphine behavioral test and Nissl staining were performed in all experimental groups. The expressions of Sequestosome-1 [P62], Unc- 51 like autophagy activating kinase [Ulk1], and microtubule-associated proteins 1A/1B light chain 3B [Lc3] genes were evaluated using reverse transcription- polymerase chain reaction [RT-PCR]
Results: E2 administration reduced the damages to the dopaminergic neurons of the substantia nigra. The motor behavior, the number of rotations, and histological tests in the treatment group showed the cell survival improvement in comparison with the control groups indicating that E2 can inhibit the neurodegeneration. P62 and Lc3 were expressed in all experimental groups while Ulk1 was not expressed in ODG group. Moreover, Ulk1 was expressed after the treatment with E2 in OE2PTG group
Conclusion: E2 prevents neurodegeneration in dopaminergic neurons of the midbrain by over-expression of Ulk1 gene and augmenting the induction of autophagy
ABSTRACT
Background: Autophagy is a mechanism disassembling the damaged organelles from the cell. This study attempted to examine the expression of several autophagy-related genes in Parkinson's disease [PD] rat model
Methods: The male Wistar rats were divided into three groups as control, sham, and lesion. In the latter group, the PD rat model was induced by the injection of 6-hydroxydopamine in the striatum. The behavioral test was conducted one [baseline] and four weeks after the surgery through apomorphine hydrochloride. Then the RT-PCR technique was employed to evaluate the expressions of p62/SQSTM, autophagy-related genes [ATG]5, ATG12, ATG16L1, ATG10, as well as GAPDH and LC3
Results: By injecting apomorphine, the striatal lesion group showed a significant contralateral rotation at fourth week as compared to the baseline. The examination of p62, ATG5, ATG12, ATG16L1, and LC3 expressions using RT-PCR revealed that p62, ATG5, ATG12, LC3, and ATG16L1 were expressed in the substantia nigra of PD rat model, while ATG10 was not expressed
Conclusion: ATG10 expression is necessary for the initiation of autophagy. Thus, these results show that autophagy deregulation occurs in the initiation stages of the process in the rat model of PD
ABSTRACT
Animal model studies have shown that MSY2 and JHDM2A genes have an important role in spermatogenesis process and fertility of male mice. But the potential role of these genes in human spermatogenesis and fertility is not known yet. Therefore, we evaluated expression ratios of these genes in testis tissues of men with normal and impaired spermatogenesis. In this experimental study, after RNA extraction and cDNA synthesis from 50 non-obstructive azoospermic and 12 normal testis tissues, the expression ratios of genes were evaluated by real time polymerase chain reaction [PCR] technique. Hematoxcylin and eosin [H and E] staining was used for histological classification of testis tissues. For statistical analysis, one way analysis of variance [ANOVA] test was carried out. Our results showed a significant reduction in mRNA level of YBX2 in samples with impaired spermatogenesis [p<0.001] compared to samples with qualitatively normal spermatogenesis and normal spermatogenesis; however, in JHDM2A gene, despite sensible reduction in gene expression level in men with impaired spermatogenesis, no significant differences were shown [p>0.05]. Furthermore in YBX2, a significant negative correlation was demonstrated between the efficiency score of spermatogenesis and the threshold cycle [CT] [r=-0.7, p<0.0001], whereas in JHDM2A, this negative correlation was not significant [r=-0.4, p=0.06]. Generally, these data indicated that YBX2 and JHDM2A genes may play an important role in male infertility, and suggested that these molecules can act as useful biomarkers for predicting male infertility
ABSTRACT
Today, due to the modern industrial life of human beings, stress has become prevalent among them and they will suffer from its complications. Exposure to stress during pregnancy can change many babies' normal physiological processes. The separate and combined effects of three common types of prenatal stress were investigated on motor learning of male offspring of rats. In the present study, pregnant NMRI rats were used. Except the control group, the other groups were stressed on the eighth day of gestation for 10 days. The motor learning of 40 male offspring rats were tested using the rotarod performance test 75 days after the experiment. The length of time that each rat could maintain its balance was recorded automatically. The study groups included control, electromagnetic field stress [intensity 1.2 mT, 50 Hz], immobility stress [for 0.5 hour - 2 times/day], social stress [6 rats kept in a small cage], and combined stress [all 3 of the above stresses]. Data were analyzed by using multiple comparisons and Tukey's tests. The motor balance of the combined stress group was lower than the control, at first timing of the first test day [P < 0.05]. In the next few days of the test, the effects of stress on learning of experimental groups were not similar. Combined stress reduced motor learning. Learning fluctuations were higher in electromagnetic field stress group compared to the other groups. The results of our study showed that prenatal combined stress can reduce motor learning of children
ABSTRACT
Recurrent pregnancy loss [RPL] is a multifactorial disorder. Environmental factors and genetics can affect pregnancy outcomes. Conflicting data suggest an association between estrogen receptor alpha [ESR1] gene polymorphisms and RPL. In this study, such association was investigated in Iranian women with RPL. In this case control study, blood samples were collected from 244 women with a history of three or more consecutive pregnancy losses and 104 healthy women with at least two live births. Using polymerase chain reaction- restriction fragment length polymorphism [PCR-RFLP], we studied -397C/T and -351A/G polymorphisms on ESR1 gene in case and control subjects. The genotypic frequencies of -397C/T and -351A/G polymorphisms on ESR1were not significantly different between RPL and control groups [p=0.20 and p=0.09, respectively]. A significantly negative correlation was observed between -397C/T and -351A/G [r=-0.852, p<0.001] in RPL women and complete linkage disequilibrium between the investigated polymorphisms was found [D': 0.959; r-square= 0.758, p<0.001]. This investigation suggests that the analyzed polymorphisms on ESR1gene are not associated with an increased risk of RPL in the studied population
ABSTRACT
The increase of stress following technology development appears to be a threat to human body organs such as nervous system. The present study was conducted aiming at investigating the effects of chronic multiple stress on morphometric changes of Betz cells in male rat cerebral cortex. In this experimental study, 18 Wistar rats were randomly divided into two equal groups. Animals of the under stress group for 10 days were exposed to different stresses, such as food deprivation, water deprivation, forced swimming, immobilization at 4[degree]C, and isolation, while the animals in control group were kept in their cages without any intervention. After the intended period, the animals were anesthetized and then their brains were removed. After fixation, samples of frontal cortex of the brain were prepared for light microscopy study. The data analysis were performed using t-test, and the significance level was considered p<0.05. The mean number and size of Betz cells in the stress groups was significantly lower compared to control group [p<0.001]. The qualitative observations also showed chromatolysis of nissl bodies, nucleus condensation, and decrease of neural processes. The results of the present study showed that chronic multiple stress can have negative effects on the rat cortical internal pyramidal layer through reducing the size and number of Betz cells; however, more studies are needed to confirm the above results.
ABSTRACT
Oocyte cryopreservation is one of the most important topics in the field of assisted reproductive technology to preserve women fertility, but relationship between cryopreservation and apoptosis is still a matter of debate. The present study was aimed to investigate the effects of vitrification on apoptosis in mouse oocytes by Cryotop method. A total of 200 germinal vesicle [GV] and 200 metaphase 2 [M2] oocytes were obtained from ovaries and fallopian tubes of NMRI mice, respectively and divided into control and experimental groups. Oocytes in experimental group were vitrified by Cryotop using vitrification medium and were kept in liquid nitrogen for one month. The survival rate of oocytes was evaluated after 2 hour incubation time. Then, the oocyte apoptosis was evaluated by TUNEL technique and compared with those in control group. The data was compared statistically using SPSS software and chi-square test. The survival rates of vitrified GV [93%] and M2 oocytes [88%] showed a significant decrease compared with the control group [P<0.05], but there was no significant difference in survival rate of both vitrified oocyte groups. The incidence of apoptosis in vitrified and control GV oocytes showed no significant difference [13% vs. 7%], but the rate of apoptosis in vitrified M2 oocytes increased significantly not only in comparison with MII control group [25% vs. 5%] but also with vitrified GV oocytes [P<0.05]. The results indicate that vitrification increases apoptosis in mouse M2 oocytes and apoptosis may play a role in M2 oocyte injury after vitrification
Subject(s)
Animals, Laboratory , Oocytes , Apoptosis , Mice , Cryopreservation , Reproductive Techniques, AssistedABSTRACT
Bone tissue engineering requires materials that are biocompatible, mechanically suited for bone function, integrated with the host skeleton, and support osteoinduction of the implanted cells for new bone formation. The aim of this study was to compare the osteogenic potential of xenograft with hydroxyapatite/beta- tricalcium phosphate [HA/beta-TCP] scaffold. New Zealand rabbits [n = 9] were divided into 3 groups. Osteoblast cells were originally isolated from rabbit iliac crest and cultured in DMEM/F12. After creating a critical-sized defect [2 x 3 cm] in rabbit tibia bone, the defect was filled with an implant of HA/TCP with osteoblasts and xenograft in the hole of left [as control] and right tibia, respectively. The new bone formation and the development of bone union within the defect were evaluated by x-ray images and eosine and hematoxylin staining at 4, 8, and 12 weeks post-operation. The bone partially formed in both groups was filled with osteoblast cultured on porous implants at 4 weeks. Over time, progressive bone regeneration was observed inside the pores. Moreover, a progressive vascular ingrowth and progressive integration with the host bone were obvious in xenograft when compared to HA/beta-TCP. A good integration between the xenograft implants and the bone was observed radiographically and confirmed by histological section. The result showed that the bone defect can be repaired using both synthetic and xenograft implants. However, the xenograft showed a better osteointegration as compared to HA/beta-TCP scaffold