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Biomedical subjects

Ritushree Kukreti

Publications and source records attributed to Ritushree Kukreti.

3 recordsLinked to original sources

Desmoplakin loss in alveolar epithelium drives Wnt/β-Catenin-mediated extracellular matrix remodeling and fibrotic signaling in vitro.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic interstitial lung disease characterized by aberrant extracellular matrix (ECM) remodeling, epithelial dysfunction, and limited therapeutic options. Genetic studies implicate Desmoplakin (DSP), a desmosomal adhesion protein, in IPF susceptibility; however, its mechanistic role remains unclear. This study aimed to investigate the role of DSP in regulating fibrotic and ECM remodeling pathways in alveolar epithelial cells. METHODS AND RESULTS: DSP was silenced using siRNA in adenocarcinoma-derived human alveolar epithelial A549 cells. DSP loss induced epithelial-to-mesenchymal transition, enhanced cell migration, and increased epithelial permeability, along with upregulation of fibrotic and ECM-associated genes. Pathway enrichment analysis of DSP interactors (STRING database) identified the Wnt/β-catenin signaling as a potential key pathway. Mechanistic validation using cycloheximide chase assays, qPCR, western blotting, immunofluorescence, and luciferase-reporter assays suggested that DSP loss destabilizes desmosomal complexes, promoting plakoglobin (γ-catenin) degradation while reducing β-catenin turnover. This was associated with increased nuclear accumulation of β-catenin and enhanced TCF/LEF-dependent transcription, leading to elevated expression of ECM-related genes, including COL1A1 and MMP9. DSP overexpression suppressed Wnt/β-catenin signaling and fibrotic gene expression, while pharmacological inhibition of this pathway attenuated DSP-dependent increases in ECM-associated gene expression. CONCLUSION: These findings suggest that DSP may function as a regulator of alveolar epithelial homeostasis and extracellular matrix remodeling in an in vitro epithelial model. Loss of DSP is associated with activation of Wnt/β-catenin-mediated fibrotic signaling, correlating with reduced plakoglobin stability. This study provides mechanistic insight into epithelial-matrix crosstalk in vitro and identifies a candidate pathway that may contribute to ECM dysregulation in IPF, the disease relevance of which will require validation in primary human alveolar epithelial cells and in vivo models.

Humans

Antiepileptic drugs carbamazepine and valproic acid mediate transcriptional activation of CYP1A1 via aryl hydrocarbon receptor and regulation of estrogen metabolism.

Cytochrome P450 1A1 (CYP1A1) actively catalyzes estrogen hydroxylation reactions and maintains the levels of neuroactive steroid estradiol. The widely prescribed first-line anti-epileptic drugs (AEDs) are considered to be a potent inducer of CYP1A1 and have also been observed to affect serum estradiol and calcium levels in patients with epilepsy. However, the ability of AEDs to interfere with CYP enzyme function and estrogen disposition is a relatively unexplored area. Here we investigate the effect of widely prescribed AEDs (carbamazepine and valproic acid) on CYP1A1 regulation and the levels of estradiol and calcium in cell supernatants of hepatocellular, HepG2, and neuronal, SH-SY5Y cells. We observed that both the AEDs significantly increased CYP1A1 expression and enzyme activity, which was accompanied by a decrease in estradiol and calcium levels in HepG2 cells. This induction of CYP1A1 mRNA and protein was fully prevented by aryl hydrocarbon receptor (AHR) knockdown and StemRegenin 1 (SR1) antagonism. Notably, the AEDs did not affect the AHR expression but regulated its nuclear translocation, potentially driving the transcriptional upregulation of CYP1A1. Furthermore, the knockdown of CYP1A1 in HepG2 cells elucidated a marked increase in estradiol and calcium levels. Later, this increase subsided upon AED exposure. Lastly, we observed a similar trend in estradiol and calcium alterations in SH-SY5Y cells on AED exposure, speculating the involvement of CYP1A1 induction via AEDs at neuronal sites. This work demonstrates that AEDs mediate the upregulation of CYP1A1 via an AHR-dependent mechanism and influence estrogen and calcium homeostasis.

Humans

Effect of antiepileptic drug monotherapy on endogenous sex hormonal profile in men and women with epilepsy.

OBJECTIVE: To assess the alterations of endogenous sex hormone profiles in patients with epilepsy (PWE) on different antiepileptic drug (AED) monotherapies compared to healthy controls and drug naïve PWE (DNPWE). METHODS: Four databases MEDLINE, EMBASE, SCOPUS, and CENTRAL were searched for analytical observational/intervention studies on the assessment of endogenous sex hormones in PWE compared to healthy controls and DNPWE. Two researchers reviewed the title/abstract, and full-text articles for the selection of the studies independently. Extracted data included information on study details, participant demographics, interventions, method of assessment and study results. The study outcomes were used to calculate the standard mean differences (SMD) and 95% confidence interval (CI) as effect size for assessing differences in the endogenous sex hormone levels between the treatment group and control/DNPWE. RESULTS: Among 5888 publications retrieved, 33 studies were included. Enzyme-inducing AEDs (EIAEDs) such as phenytoin (men: SMD = 1.36; 95%CI = 1.06,1.66) and carbamazepine (men: SMD = 0.71; 95%CI = 0.39, 1.04 and women: SMD = 0.54; 95%CI = 0.25, 0.83) and weak-EIAED oxcarbazepine (men: SMD = 0.62; 95%CI = 0.26,0.99) increased the SHBG levels in PWE compared to control. The same trend was observed when comparing it to DNPWE. No significant changes in SHBG were observed for non-EIAEDs valproic acid, lamotrigine and levetiracetam in men. Lamotrigine significantly reduced SHBG in women (SMD = -0.50; 95%CI = -0.85, -0.16) compared to controls. Testosterone (T) levels were significantly reduced for both carbamazepine (SMD = -0.39; 95%CI = -0.67, -0.11) and valproic acid (SMD = -0.48; 95%CI = -0.74, -0.21) treated men compared to control. SIGNIFICANCE: Our findings emphasize the importance of screening the endogenous sex hormonal profile in PWE on AED monotherapies to evaluate the associated endocrine-related perturbations which may impact reproductive functions.

Humans