Stem Cells
Vahid Akbarinejad; Parviz Tajik; Mansoureh Movahedin; Reza Youssefi
Volume 8, Issue 1 , March 2017, , Pages 7-13
Abstract
Testosterone is believed to play a significant role in spermatogenesis, but its contribution to the process of spermatogenesis is not completely understood. Given that extracellular matrix (ECM) facilitates differentiation of spermatogonial stem cells (SSCs) during culture, the present study was conducted ...
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Testosterone is believed to play a significant role in spermatogenesis, but its contribution to the process of spermatogenesis is not completely understood. Given that extracellular matrix (ECM) facilitates differentiation of spermatogonial stem cells (SSCs) during culture, the present study was conducted to elucidate whether testosterone contribute to the permissive effect of ECM on SSCs differentiation. In experiment 1, testosterone production was measured in testicular cells cultured for 12 days on ECM or plastic (control). In experiment 2, testosterone production was assessed in testicular cells cultured on ECM or plastic (control) and exposed to different concentrations of hCG. In experiment 3, the gene expression of factors involved in testosterone production was analyzed. Testosterone concentration was lower in ECM than in the control group in experiment 1 (p < 0.05). In experiment 2, testosterone concentration was increased in response to hCG in both groups but cells cultured on ECM were more responsive to hCG than those cultured on plastic (p < 0.05). In the experiment 3, qRT-PCR revealed the inhibitory effect of ECM on the gene expression of steroidogenic acute regulatory protein (StAR) (p < 0.05). Nevertheless, the expression of LH receptor was greater in ECM-exposed than in unexposed cells (p < 0.05). In conclusion, the present study showed that inhibiting the expression of StAR, ECM could lower testosterone production by Leydig cells during in vitro culture. In addition, the results indicated that ECM could augment the responsiveness of Leydig cells to hCG through stimulating the expression of LH receptor.
Theriogenology
Reza Youssefi; Parviz Tajik; Mansoureh Movahedin; Vahid Akbarinejad
Volume 7, Issue 4 , December 2016, , Pages 275-280
Abstract
Enrichment of cell suspension with germ cells prior to injection into recipient seminiferous tubules is of importance in spermatogonial stem cells (SSCs) transplantation. Knock-out serum replacement (KSR) has been reported to enhance the proliferation of murine SSCs and human embryonic stem cells. The ...
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Enrichment of cell suspension with germ cells prior to injection into recipient seminiferous tubules is of importance in spermatogonial stem cells (SSCs) transplantation. Knock-out serum replacement (KSR) has been reported to enhance the proliferation of murine SSCs and human embryonic stem cells. The aim of the present study was to investigate the effect of KSR versus fetal bovine serum (FBS) and their interaction on colonization of bovine SSCs in vitro. When FBS (10%) was replaced with KSR (10%), a significant increase in the colonization of SSCs and the expression of Thy1, as marker for enrichment of SSCs, was observed. It was revealed that the lesser proliferative effect of FBS as well as the greater proliferative impact of KSR on SSCs colonization were not irreversible as cells having been cultured with FBS (10%) for three days with low colonization showed high rate of colonization in response to KSR (10%) and cells having been cultured with KSR (10%) with high colonization experienced low rate of colonization in response to FBS (10%). Further, it was shown that FBS did not contain factors inhibiting SSCs colonization and it simply lacked factors essential for SSCs proliferation because the combination of FBS (5%) and KSR (5%) resulted in even greater rate of colonization than did KSR (10%). In conclusion, the present study showed that addition of KSR to culture medium would significantly increase SSCs proliferation.
Nutrition
Faramarz Gharagozlou; Reza Youssefi; Vahid Akbarinejad
Volume 7, Issue 2 , June 2016, , Pages 105-110
Abstract
The present study was conducted to evaluate the effect of fish oil supplementation prior to mating on secondary sex ratio of pups (the proportion of males at birth) in bitches. Sixty five bitches (German Shepherd, n = 35; Husky, n = 30) were enrolled in the study. Bitches (140-150 days post-estrus) were ...
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The present study was conducted to evaluate the effect of fish oil supplementation prior to mating on secondary sex ratio of pups (the proportion of males at birth) in bitches. Sixty five bitches (German Shepherd, n = 35; Husky, n = 30) were enrolled in the study. Bitches (140-150 days post-estrus) were given 2% per dry matter intake palm oil and fish oil in the control (n = 33) and treatment (n = 32) groups, respectively. To induce estrus, bitches were received equine chorionic gonadotropin (eCG) administration (50 IU kg-1) 30 days after nutritional supplementation followed by human chorionic gonadotropin (hCG) administration (500 IU per dog) seven days later. Bitches were introduced to dogs of the same breed after hCG administration. The weight of bitches was increased over time (p < 0.05), but their weight change was not different between two groups (p > 0.05). The mating rate, pregnancy rate and litter size were not influenced by treatment and breed. Secondary sex ratio was higher in the treatment (105/164; 64.00%) than in the control (68/147; 46.30%) group (p < 0.05; adjusted odds ratio = 2.068). Moreover, secondary sex ratio was higher in Husky bitches (88/141; 62.40%) compared to German Shepherd (85/170; 50.00%; p < 0.05; adjusted odds ratio = 1.661). In conclusion, the present study showed that inclusion of fish oil in the diet of bitches prior to mating could increase the proportion of male pups at birth. In addition, it appears that there might be variation among dog breeds with regard to the sex ratio of offspring.
Stem Cells
Vahid Akbarinejad; Parviz Tajik; Mansoureh Movahedin; Reza Youssefi
Volume 7, Issue 2 , June 2016, , Pages 149-153
Abstract
The receptors 1 and 2 of fibroblast growth factor (FGFR1 and FGFR2, respectively) have been observed in all types of testicular cells. Culture on extracellular matrix (ECM) has been observed to lead to initiation of differentiation in spermatogonial stem cells (SSCs). The present study was carried out ...
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The receptors 1 and 2 of fibroblast growth factor (FGFR1 and FGFR2, respectively) have been observed in all types of testicular cells. Culture on extracellular matrix (ECM) has been observed to lead to initiation of differentiation in spermatogonial stem cells (SSCs). The present study was carried out to investigate whether FGFR1 and FGFR2 play a role in SSCs differentiation. Following isolation, bovine testicular cells were cultured on ECM-coated or uncoated (control) plates for 12 days. The gene expression of THY1, cKIT, FGFR1 and FGFR2 was evaluated using quantitative real-time polymerase chain reaction (PCR). Results related to the gene expression of markers of with undifferentiated (THY1) and differentiated (cKIT) spermatogonia implicated stimulation of self-renewal and differentiation in cells cultured on ECM-coated and uncoated plates, respectively (p < 0.05). Concomitantly, the expression of FGFR2 increased during culture in the ECM group (p < 0.05), whereas it did not change in the control group (p > 0.05). As a result, the gene expression of FGFR2 was greater in the ECM than control group (p < 0.05). Nevertheless, FGFR1 expression did not change during culture in the control and ECM groups (p > 0.05). In conclusion, the present study revealed the potential role of FGFR2 in differentiation of SSCs during culture on ECM.
Epidemiology
Faramarz Gharagozlou; Reza Youssefi; Mehdi Vojgani; Vahid Akbarinejad; Ghazaleh Rafiee
Volume 7, Issue 2 , June 2016, , Pages 169-172
Abstract
Maternal testosterone has been indicated to affect sex ratio of offspring. The present study was conducted to elucidate the role of androgen receptor in this regard by blockade of androgen receptor using flutamide in female mice. Mice were randomly assigned to two experimental groups. Mice in the control ...
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Maternal testosterone has been indicated to affect sex ratio of offspring. The present study was conducted to elucidate the role of androgen receptor in this regard by blockade of androgen receptor using flutamide in female mice. Mice were randomly assigned to two experimental groups. Mice in the control (n = 20) and treatment (n = 20) groups received 8 IU equine chorionic gonadotropin (eCG) followed by human chorionic gonadotropin (hCG) injection (8 IU) 47 hr later. In addition, mice in the control and treatment groups received four injections of ethanol-saline vehicle and flutamide solution (2.50 mg), respectively, started from 1 hr before eCG injection until hCG injection at 12-hr intervals. Conception rate was not different between the treatment (18/20: 90.00%) and control (19/20: 95.00%) groups (p > 0.05). Litter size was higher in the treatment (8.22 ± 0.26) than control (7.21 ± 0.28) group (p < 0.05). Male sex ratio was lower in the flutamide-treated mice (67/148: 45.30%) as compared with the untreated ones (80/137: 58.40%; odds ratio = 1.69; p < 0.05). In conclusion, the results showed that androgen receptor blockade could skew sex ratio of offspring toward females implying that the effect of testosterone on sex ratio might be through binding to androgen receptor. In addition, the blockade of androgen receptor using flutamide appeared to enhance litter size.