Publications by authors named "Soumya Maity"

Mechanisms underlying the cardiovascular-kidney-metabolic (CKM) syndrome are unknown, although key small molecule metabolites may be involved. Bulk and spatial metabolomics identified adenine to be upregulated and specifically enriched in coronary blood vessels in hearts from patients with diabetes and left ventricular hypertrophy. Single nucleus gene expression studies revealed that endothelial methylthioadenosine phosphorylase (MTAP) was increased in human hearts with hypertrophic cardiomyopathy.

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Article Synopsis
  • Lactate is a key indicator of mitochondrial dysfunction, and recent studies are exploring its significance in diabetic kidney disease (DKD), particularly in individuals with type 2 diabetes (T2D) and type 1 diabetes (T1D).
  • In cohorts of T2D patients (HUNT3, SMART2D, CRIC), higher urine lactate levels were linked to worse kidney function and faster declines in glomerular filtration rate; additionally, increased lactate levels were observed in T1D patients during glucose challenges.
  • The study suggests that elevated lactate, particularly in diabetic conditions, may inhibit important mitochondrial processes and contribute to the pathology of DKD, potentially through mechanisms
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Kidney dysfunction often leads to neurological impairment, yet the complex kidney-brain relationship remains elusive. We employed spatial and bulk metabolomics to investigate a mouse model of rapid kidney failure induced by mouse double minute 2 ( conditional deletion in the kidney tubules to interrogate kidney and brain metabolism. Pathway enrichment analysis of focused plasma metabolomics panel pinpointed tryptophan metabolism as the most altered pathway with kidney failure.

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Reduced kidney AMPK activity is associated with nutrient stress-induced chronic kidney disease (CKD) in male mice. In contrast, female mice resist nutrient stress-induced CKD. The role of kidney AMPK in sex-related organ protection against nutrient stress and metabolite changes was evaluated in diabetic kidney tubule-specific AMPKγ2KO (KTAMPKγ2ΚΟ) male and female mice.

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The most abundant cellular divalent cations, Mg (mM) and Ca (nM-μM), antagonistically regulate divergent metabolic pathways with several orders of magnitude affinity preference, but the physiological significance of this competition remains elusive. In mice consuming a Western diet, genetic ablation of the mitochondrial Mg channel Mrs2 prevents weight gain, enhances mitochondrial activity, decreases fat accumulation in the liver, and causes prominent browning of white adipose. Mrs2 deficiency restrains citrate efflux from the mitochondria, making it unavailable to support de novo lipogenesis.

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The plasticity of proximal tubular epithelial cells in response to TGFβ contributes to the expression of TWIST1 to drive renal fibrosis. The mechanism of TWIST1 expression is not known. We show that both PI3 kinase and its target mTORC2 increase TGFβ-induced TWIST1 expression.

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Mitochondrial calcium ( Ca ) uptake occurs via the Mitochondrial Ca Uniporter (MCU) complex and plays a critical role in mitochondrial dynamics, mitophagy, and apoptosis. MCU complex activity is in part modulated by the expression of its regulatory subunits. Cardiovascular disease models demonstrated altered gene/protein expression of one or multiple subunits in different cells, including vascular endothelial cells (ECs).

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The mitochondrial calcium (Ca) uniporter (MCU) channel is responsible for mitochondrial Ca influx. Its expression was found to be upregulated in endothelial cells (ECs) under cardiovascular disease conditions. Since the role of MCU in regulating cytosolic Ca homeostasis in ECs exposed to shear stress (SS) is unknown, we studied mitochondrial Ca dynamics (that is known to decode cytosolic Ca signaling) in sheared ECs.

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Proximal tubular epithelial cells respond to transforming growth factor β (TGFβ) to synthesize collagen I (α2) during renal fibrosis. The oncoprotein DJ-1 has previously been shown to promote tumorigenesis and prevent apoptosis of dopaminergic neurons; however, its role in fibrosis signaling is unclear. Here, we show TGFβ-stimulation increased expression of DJ-1, which promoted noncanonical mTORC1 and mTORC2 activities.

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SARS-CoV-2 is a newly identified coronavirus that causes the respiratory disease called coronavirus disease 2019 (COVID-19). With an urgent need for therapeutics, we lack a full understanding of the molecular basis of SARS-CoV-2-induced cellular damage and disease progression. Here, we conducted transcriptomic analysis of human PBMCs, identified significant changes in mitochondrial, ion channel, and protein quality-control gene products.

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Transformation of naive macrophages into classically (M1) or alternatively (M2) activated macrophages regulates the inflammatory response. Here, we identified that distinct Ca entry channels determine the IFNγ-induced M1 or IL-4-induced M2 transition. Naive or M2 macrophages exhibit a robust Ca entry that was dependent on Orai1 channels, whereas the M1 phenotype showed a non-selective TRPC1 current.

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Recently we showed that homoarginine supplementation confers kidney protection in diabetic mouse models. In this study we tested whether the protective effect of homoarginine is nitric oxide synthase-3 (NOS3)-independent in diabetic nephropathy (DN). Experiments were conducted in NOS3 deficient (NOS3 ) mice and their wild type littermate using multiple low doses of vehicle or streptozotocin and treated with homoarginine via drinking water for 24 weeks.

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Mg is the most abundant divalent cation in metazoans and an essential cofactor for ATP, nucleic acids, and countless metabolic enzymes. To understand how the spatio-temporal dynamics of intracellular Mg (Mg) are integrated into cellular signaling, we implemented a comprehensive screen to discover regulators of Mg dynamics. Lactate emerged as an activator of rapid release of Mg from endoplasmic reticulum (ER) stores, which facilitates mitochondrial Mg (Mg) uptake in multiple cell types.

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Fibrosis is the final common pathway in the pathophysiology of most forms of chronic kidney disease (CKD). As treatment of renal fibrosis still remains largely supportive, a refined understanding of the cellular and molecular mechanisms of kidney fibrosis and the development of novel compounds are urgently needed. Whether arginases play a role in the development of fibrosis in CKD is unclear.

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Interaction of transforming growth factor-β (TGFβ)-induced canonical signaling with the noncanonical kinase cascades regulates glomerular hypertrophy and matrix protein deposition, which are early features of glomerulosclerosis. However, the specific target downstream of the TGFβ receptor involved in the noncanonical signaling is unknown. Here, we show that TGFβ increased the catalytic loop phosphorylation of platelet-derived growth factor receptor β (PDGFRβ), a receptor tyrosine kinase expressed abundantly in glomerular mesangial cells.

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The tricarboxylic acid (TCA) cycle converts the end products of glycolysis and fatty acid β-oxidation into the reducing equivalents NADH and FADH Although mitochondrial matrix uptake of Ca enhances ATP production, it remains unclear whether deprivation of mitochondrial TCA substrates alters mitochondrial Ca flux. We investigated the effect of TCA cycle substrates on MCU-mediated mitochondrial matrix uptake of Ca, mitochondrial bioenergetics, and autophagic flux. Inhibition of glycolysis, mitochondrial pyruvate transport, or mitochondrial fatty acid transport triggered expression of the MCU gatekeeper MICU1 but not the MCU core subunit.

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Exposure to chronic hyperglycemia because of diabetes mellitus can lead to development and progression of diabetic kidney disease (DKD). We recently reported that reduced superoxide production is associated with mitochondrial dysfunction in the kidneys of mouse models of type 1 DKD. We also demonstrated that humans with DKD have significantly reduced levels of mitochondrion-derived metabolites in their urine.

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The mechanism of PTEN repression by high glucose in diabetic nephropathy is not known. Using proximal tubular cells, we show that inhibition of PI3 kinase/Akt and their inactive enzymes prevents high glucose-induced PTEN downregulation. Similarly, rapamycin (Rapa) and shRaptor block suppression of PTEN by high glucose.

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S6 kinase acts as a driver for renal hypertrophy and matrix accumulation, two key pathologic signatures of diabetic nephropathy. As a post-translational modification, S6 kinase undergoes acetylation at the C terminus. The role of this acetylation to regulate kidney glomerular cell hypertrophy and matrix expansion is not known.

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TGFβ contributes to mesangial cell hypertrophy and matrix protein increase in various kidney diseases including diabetic nephropathy. Deptor is an mTOR-interacting protein and suppresses mTORC1 and mTORC2 activities. We have recently shown that TGFβ-induced inhibition of deptor increases the mTOR activity.

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The antioxidant property of the 70% aqueous ethanol extract of Phyllanthus amarus roots and its ether-soluble, ethyl acetate-soluble, and aqueous fractions were investigated by various in vitro assays. The root extracts showed higher DPPH, hydroxyl, superoxide, and nitric oxide radical scavenging and reducing power activity. Among all the samples, the ethyl acetate-soluble fraction demonstrated highest radical scavenging activity and total phenolics content.

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The ability of ethanol extract of Phyllanthus amarus root (EEPA) to decrease bilirubin level and oxidative stress in phenylhydrazine-induced neonatal jaundice in mice was investigated. Administration of phenylhydrazine (75 mg/kg b.w.

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Aim Of The Study: We sought to determine the efficacy as antioxidant and safety profile of the polyherbal formulation in geriatric patients of eastern India.

Materials And Methods: The study was double-blind, randomized including placebo controlled and was approved by the ethical committee of SSKM hospital. Geriatric patients attending the OPD (outpatient department) of SSKM hospital formed the study group.

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