Biology subjects

Sutliff, R. L.

Publications and source records attributed to Sutliff, R. L..

3 recordsLinked to original sources

bioRxiv2022

Candesartan treatment preserves learning and working memory in female TgF344-AD rats

BackgroundTargeting the renin angiotensin system, especially with angiotensin receptor II blockers (ARB), and related vascular dysfunction is a promising therapeutic intervention for cognitive impairment including Alzheimers Disease (AD). The underlying mechanisms of the effects of ARB is unclear. This study sought to examine if treatment with candesartan, an ARB, affects neurobehavioral manifestation and the underlying neuro- and vascular mechanisms in male and female TgF344-AD rats. MethodsCandesartan or vehicle was administered to TgF344-AD rats (n=127) daily from 12-months to 18-months of age. Behavioral assays (spontaneous alternation test, novel object recognition, water radial arm maze) and neuropathologic assessment were completed along with brain proteome and measures of contractility in 12- and 18-month rat brains. ResultsUntreated 18-month TgF344-AD showed impairments in learning and increased perseverative working memory errors on the water radial arm maze (WRAM). These behavioral changes were corrected with candesartan treatment in female rats only. Treatment with candesartan was also associated with improved vascular reactivity and reduced blood pressure in both wild type and TgF344-AD male and female rats. Although there was no effect on amyloid-{beta}, treatment with candesartan reduced whole brain clusterin, an AD-risk associated protein, and GFAP in female TgF344-AD. ConclusionsOur results demonstrate that candesartan administered in the early stages of AD has a sexual dimorphic response in Tgf344-AD rat, where it reduced cognitive disturbances only in female TgF344-AD rat. These effects appear to be independent of changes in blood pressure and amyloid-{beta} reduction and are likely mediated through mechanisms related to clusterin and GFAP pathways.

neuroscience↗

bioRxiv2022

PPARγ/ETV2 Axis Regulates Endothelial-to-Mesenchymal Transition in Pulmonary Hypertension

Endothelial-to-mesenchymal transition (EndoMT) plays an important role in pulmonary hypertension (PH). Also, the molecular mechanisms regulating EndoMT in PH remain to be defined. In this study, we first showed that reduced expression of the transcription factors ETV2 (ETS variant 2) and PPAR{gamma} (Peroxisome Proliferator-Activated Receptor gamma) along with reduced endothelial markers and increased EndoMT markers were consistently observed in lungs and pulmonary artery endothelial cells (PAECs) of idiopathic pulmonary arterial hypertension (IPAH) patients, in hypoxia-exposed mouse lungs, human PAECs, and in induced EndoMT cells. Base on this observation, we aimed to investigate the function of ETV2 and PPAR{gamma} in EndoMT. We have explored the function of ETV2 and PPAR{gamma} and its mechanism in PH using in Etv2+/- mice or PPAR{gamma} KO mice. Etv2+/- mice spontaneously developed PH and right ventricular hypertrophy, associated with increased EndoMT markers and decreased EC markers. PPAR{gamma} transcriptionally activated the ETV2 promoter. Endothelial PPAR{gamma} expression in mice is positively correlated with ETV2 expression, but inversely with EndoMT markers. Overexpression of ETV2 in hypoxia-exposed rat pulmonary artery led to vascular relaxation. We conclude that PPAR{gamma}-ETV2 signaling can function as a novel pathway in PH pathogenesis by attenuating EndoMT.

physiology↗

bioRxiv2021

Polycomb group protein CBX7 represses cardiomyocyte proliferation via modulation of the TARDBP/Rbm38 axis

Cardiomyocyte (CM) proliferation notably decreases during the perinatal period. At present, regulatory mechanisms for this loss of proliferative capacity is poorly understood. CBX7, a polycomb group (PcG) protein, regulates the cell cycle but its role in CM proliferation is unknown. Here, we report that CBX7 inhibits proliferation of perinatal CMs by controlling TARDBP/Rbm38 pathway. Gene expression profiling demonstrated that CBX7 expression in the heart was low during the prenatal period, abruptly increased during the perinatal period, and sustained constantly throughout the adulthood. CBX7, when overexpressed via adenoviral transduction in neonatal CMs, reduced proliferation and promoted multinucleation of the CMs. Mutant mice carrying targeted inhibition of CBX7 in CMs exhibited cardiomegaly with increased proliferation of CMs at postnatal stages. Mechanistically, CBX7 interacted with TAR DNA-binding protein 43 (TARDBP) and positively regulated its downstream target, RNA Binding Motif Protein 38 (RBM38). Rbm38 was upregulated in the postnatal hearts and overexpression of RBM38 reduced proliferation of neonatal CMs. Together, this study provides a novel insight into the role of CBX7 in regulation of CM proliferation during the perinatal period.

developmental biology↗