Purpose: To investigate the effect of methimazole-induced postnatal hypothyroidism on the retinal maturation and to study Sirtuin 2 (SIRT2) level in the hypothyroidic rat retina.
Methods: Twenty newborn Wistar albino rat pups were used in this prospective, randomized study. Wistar albino rats, weight 250-300 g, were impregnated (without addition of any drug) and were fed normally. Rat pups were randomly divided into two groups and were fed with breast milk. After weaning till they were 90 days of age, rat pups received the same water as their lactating mothers drank. Group 1 (methimazole (MMI)-induced hypothyroidy group), rats were given MMI-water, whereas, in Group 2, normal tap water. When the pups were 90 days of age, 20 rat pups were decapitated and the eyes were isolated. Eyes were investigated using histological, histomorphometric and immunohistochemistrical techniques.
Results: No histological difference was seen between the groups stained with hematoxylin and eosin. In both groups the retinal layer structures and cells were observed as normal. The examples in the groups had a normal distribution for retinal thickness (pixel) measure. The mean value (mean ± std. deviation) was 554.7 ± 228.4 in the control group and 494.7 ± 129.4 in the hypothyroidy group. There was no significance between the groups in terms of retinal thickness (p = 0.231). However, immunohistochemistry revealed that SIRT2 was weaker stained in the ganglion cell layer and visual cell layer in the hypothyroidy group compared to the control group.
Conclusion: Postnatal hypothyroidism altered the retinal cytoarchitecture and layering which are regulated by thyroid hormones (THs) during retinal maturation in the postnatal period. THs may act by the induction of the SIRT family proteins or through their receptors. Postnatal screenings for THs levels are very important to provide normal retinal development.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.3109/15569527.2015.1007509 | DOI Listing |
IBRO Neurosci Rep
June 2025
Department of Human Anatomy and Medical Physiology, Faculty of Health Sciences, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya.
Background: Maternal folate usage is essential for neurodevelopment, but its effects on cerebellar structure are unclear. Cerebellum undergoes a protracted period of development, making it sensitive to maternal nutritional imbalances. Astrocytes are necessary for cerebellar cortex structure and function.
View Article and Find Full Text PDFIntroduction: This study designed to examine whether social/ environmental experiences can induce the epigenetic modification, and influence the associated physiology and behaviour. To test this, we have used social stress [prenatal stress (PNS)] model and then housed at environmental enrichment (EE) condition to evaluate the interaction between specific epigenetic modification and its influence on behaviour.
Methods: Pregnant rats were randomly divided into a control group, PNS group, and PNS+EE group.
Cardiovasc Toxicol
January 2025
Department of Physiology, Pharmacology and Toxicology, West Virginia University School of Medicine, Morgantown, WV, USA.
Pregnancy is a vulnerable time with significant cardiovascular changes that can lead to adverse outcomes, which can extend into the postpartum window. Exposure to emissions from electronic cigarettes (Ecig), commonly known as "vaping," has an adverse impact on cardiovascular function during pregnancy and post-natal life of offspring, but the postpartum effects on maternal health are poorly understood. We used a Sprague Dawley rat model, where pregnant dams are exposed to Ecigs between gestational day (GD)2-GD21 to examine postpartum consequences.
View Article and Find Full Text PDFCardiovasc Toxicol
January 2025
Department of Physiology, Pharmacology, and Toxicology, West Virginia University, Morgantown, WV, 26505, USA.
Engineered nanomaterials (ENM) are capable of crossing the placental barrier and accumulating in fetal tissue. Specifically, the ENM nano-titanium dioxide (nano-TiO), has been shown to accumulate in placental and fetal tissue, resulting in decreased birthweight in pups. Additionally, nano-TiO is an established cardiac toxicant and regulator of glucose homeostasis, and exposure in utero may lead to serious maladaptive responses in cardiac development and overall metabolism.
View Article and Find Full Text PDFJ Dev Orig Health Dis
January 2025
Postgraduate Program in Physiological Sciences, State University of Londrina, Londrina, Parana, Brazil.
Nutritional status during the developmental periods leads to predisposition to several diseases and comorbidities, highlighting metabolic and reproductive changes throughout adult life, and in the next generations. One of the experimental models used to induce undernutrition is litter size expansion, which decreases the availability of breast milk to pups and delays development. This work evaluated the effects of maternal undernutrition induced by litter size expansion, a maternal undernutrition preconception model, on the metabolic and reproductive alterations of the offspring.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!