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Maryam Salimi Abolfazl Shirazi Mohsen Norouzian Ameneh Jafari Haleh Edalatkhah Maryam Mehravar Mohammad Majidi Mohammad Mahdi Mehrazar 《Reports of Biochemistry & Molecular Biology》2020,9(3):357
Background:Currently, the efficient production of chimeric mice and their survival are still challenging. Recent researches have indicated that preimplantation embryo culture media and manipulation lead to abnormal methylation of histone in the H19/Igf2 promotor region and consequently alter their gene expression pattern. This investigation was designed to evaluate the relationship between the methylation state of histone H3 and H19/Igf2 expression in mice chimeric blastocysts.Methods:Mouse 129/Sv embryonic stem cells (mESCs) expressing the green fluorescent protein (mESCs-GFP) were injected into the perivitelline space of 2.5 days post-coitis (dpc) embryos (C57BL/6) using a micromanipulator. H3K4 and H3K9 methylation, and H19 and Igf2 expression was measured by immunocytochemistry and q-PCR, respectively, in blastocysts. Results:Histone H3 trimethylation in H3K4 and H3K9 in chimeric blastocysts was significantly less and greater, respectively (p< 0.05), than in controls. H19 expression was significantly less (p< 0.05), while Igf2 expression was less, but not significantly so, in chimeric than in control blastocysts.Conclusion:Our results showed, that the alteration ofH3K4me3 and H3K9me3 methylation, change H19/Igf2 expression in chimeric blastocysts.Key Words: Chimeric blastocysts, H19/Igf2, Histone 3 (H3) methylation 相似文献
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Journal of Biological Physics - The nerve cells are responsible for transmitting messages through the action potential, which generates electrical stimulation. One of the methods and tools of... 相似文献
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Farshad Malihi Azadeh Hosseini-Tabatabaei Hadi Esmaily Reza Khorasani Maryam Baeeri Mohammad Abdollahi 《Central European Journal of Biology》2009,4(3):369-380
Type 1 diabetes mellitus (T1DM) is characterized by an impairment of the insulin-secreting beta cells with an immunologic
base. Inflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β, and free radicals are believed
to play key roles in destruction of pancreatic β cells. The present study was designed to investigate the effect of Silybum marianum seed extract (silymarin), a combination of several flavonolignans with immunomodulatory, anti-oxidant, and anti-inflammatory
potential on streptozotocin (STZ)-induced T1DM in mouse. Experimental T1DM was induced in male albino mice by IV injection
of multiplelow- doses of STZ for 5 days. Seventy-two male mice in separate groups received various doses of silymarin (20,
40, and 80 mg/kg) concomitant or after induction of diabetes for 21 days. Blood glucose and pancreatic biomarkers of inflammation
and toxic stress (IL-1β, TNF-α, myeloperoxidase, lipid peroxidation, protein oxidation, thiol molecules, and total antioxidant
capacity) were determined. Silymarin treatment reduced levels of inflammatory cytokines such as TNF-α and IL-1β and oxidative
stress mediators like myeloperoxidase activity, lipid peroxidation, carbonyl and thiol content of pancreatic tissue in an
almost dose dependent manner. No marked difference between the prevention of T1DM and the reversion of this disease by silymarin
was found. Use of silymarin seems to be helpful in T1DM when used as pretreatment or treatment. Benefit of silymarin in human
T1DM remains to be elucidated by clinical trials. 相似文献
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Seyed Mahdi Hosseiniyan Khatibi Keyvan Kheyrolahzadeh Abolfazl Barzegari Yalda Rahbar Saadat Sepideh Zununi Vahed 《Journal of cellular physiology》2020,235(11):7731-7746
Medicinal signaling cells (MSCs) are multipotent cells derived from mammalian bone marrow and periosteum that can be extended in culture. They can keep their ability in vitro to form a variety of mesodermal phenotypes and tissues. Over recent years, there has been great attention over MSCs since they can impact the organ transplantation as well as autoimmune and bacterial diseases. MSCs can secrete different bioactive factors such as growth factors, antimicrobial peptides/proteins and cytokines that can suppress the immune system and prevent infection via direct and indirect mechanisms. Moreover, MSCs are able to increase bacterial clearance in sepsis models by producing antimicrobial peptides such as defensins, cathelicidins, lipocalin and hepcidin. It is the aim of the present review to focus on the antibacterial effector functions of MSCs and their mechanisms of action against the pathogenic microbes. 相似文献