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Chowdhury, U.

Publications and source records attributed to Chowdhury, U..

3 recordsLinked to original sources

Mitocurcumin mediated redox disruption and metabolic rewiring induces tumor regression in Drosophila intestinal stem cell tumors

Mitochondria-targeted modulation of redox homeostasis has emerged as a promising strategy for controlling pathological cell proliferation. Here, we investigate the effects of Mitocurcumin in a Yorkie-driven intestinal stem cell tumor model in Drosophila. Using an integrative, genetically tractable approach combining in silico molecular modelling with in vivo functional analyses, we identify thioredoxin reductase (TrxR) as a conserved redox-associated target of Mitocurcumin. Docking and molecular dynamics simulations predict a stable interaction of Mitocurcumin with both Drosophila and mammalian TrxR homologs. Functionally, Mitocurcumin treatment reduces mitotic activity, elevates reactive oxygen species (ROS) selectively within escargot-positive intestinal stem cell population, enhances apoptosis in the tumor-bearing guts, and causes significant mitochondrial membrane depolarization. These cellular effects coincide with dose-dependent regression of Yorkie-induced intestinal hyperplasia. Despite mitochondrial functional impairment, mitochondrial morphology remains largely preserved, suggesting primary disruption of redox buffering rather than structural collapse. Metabolomic profiling of these guts further reveals remodelling of energy metabolism consistent with adaptive responses to oxidative stress. Importantly, Mitocurcumin alleviates tumor-associated organismal bloating and significantly extends lifespan indicating a previously uncharacterized systemic, organism-wide response to Mitocurcumin treatment in an in vivo scenario. Collectively, our findings establish TrxR-mediated redox regulation as a critical vulnerability in Yorkie-driven hyperproliferation and highlight the utility of Drosophila as an integrative in vivo platform for evaluating mitochondria-targeted bioactive molecules.

cancer biology↗

Drosophila midgut tumor-induced insulin resistance systemically remodels lymph gland hematopoiesis during cancer cachexia

Cancer cachexia involves systemic metabolic deregulation along with classical features of muscle wasting, lipolysis, and chronic inflammation. While tumor non-autonomous effects on peripheral organs are recognized, how the tumor rewires the circulating immune cells and hematopoiesis remains unclear. We utilized a Drosophila larval cancer cachexia model by expressing yki3SA in the adult midgut precursors (AMP), which gives rise to a tumor in the larval midgut and recapitulates key cachectic phenotypes, including insulin resistance. Tumor-induced cachexia results in perturbed blood cell homeostasis with a reduced niche and aberrant blood cell differentiation in the larval hematopoietic organ, the lymph gland (LG). Bulk RNA-seq analysis of circulating hemocytes from tumor-bearing larvae revealed upregulation of multiple cachectic ligands, notably ImpL2, an insulin antagonist. We demonstrate that elevated ImpL2 levels reduce LG niche size and promote aberrant blood cell differentiation. Elevated ImpL2 levels and systemic insulin resistance in the tumor-induced cachexia conditions result in abrogation of insulin signaling in the niche-progenitor micro-environment in the LG. DE-cadherin levels in the primary LG lobe are perturbed, and Wingless signaling is down-regulated, driving prohemocyte differentiation. A genetic mimic of systemic ImpL2 overexpression or high sugar diet (HSD) conditions recapitulates these LG phenotypes due to abrogation of the Insulin-Wingless signaling axis. Hemocyte-specific ImpL2 depletion in HSD-fed larvae rescued these defects, suggesting a regulatory role for circulating hemocyte-derived ImpL2. Our findings reveal that hemocyte-derived factors actively contribute to systemic insulin resistance, causing hematopoietic remodeling in cancer cachexia.

cancer biology↗

HSF1 Activator Azadiradione Ameliorates Parkinson Disease and Extends Lifespan in Preclinical Models: Analysis of Underlying Molecular Mechanism

Parkinsons disease (PD) affects millions worldwide, with no efficient therapy currently available. A major cause of the initiation and progression of this degenerative disease is the dysfunctional cellular protein quality control system (PQC), leading to the accumulation of toxic protein aggregates in neurons. We previously reported azadiradione (AZD), a small molecule (MW 451 Da), as a potent inducer of heat shock factor 1 (HSF1) activity, which could alleviate cellular toxicity induced by misfolded proteins by upregulating the levels of inducible molecular chaperones and proteasome activity. Here, we show the multifaceted effect of AZD in enhancing the capacity of PQC machinery in cells, fruit flies, and a PD mouse model. AZD activated HSF1 by promoting its phosphorylation at S326 through MEK. In parallel, AZD boosted protein degradation through increased chymotrypsin-like proteasome activity, upregulation of the ubiquitin ligase CHIP. AZD induced autophagy, marked by elevated levels of Beclin 1, ATG7, and ULK1 phosphorylation at S555, along with mTORC1 inhibition via AMPK activation. Surprisingly, the calorie restriction pathway was also upregulated upon AZD treatment, as demonstrated by the enhanced phosphorylation of FOXO3 and FOXO1, along with increased activity of their target enzymes SOD and catalase. Notably, AKT activity was also suppressed in AZD-treated cells. In vivo, AZD improved motor function, dopaminergic neuron survival, and tyrosine hydroxylase activity in an MPTP-induced mouse model of PD, and extended lifespan in Drosophila without compromising fertility or mobility. These findings highlight AZD as a promising therapeutic candidate for restoring PQC and mitigating PD pathology.

molecular biology↗