Biology subjects

Bhatla, N.

Publications and source records attributed to Bhatla, N..

9 recordsLinked to original sources

bioRxiv2023

Upregulated GRP78 and sFlt-1 in preeclampsia induces IRE1 and ATF6 arms of UPR leading to ER stress in placental cells

IntroductionAmongst vivid and diversified stresses which placenta in preeclampsia undergoes, ER stress has been a hal of the fame which is an insinuation of ill-fated UPR. In our previous study, we have already reported activation of PERK arm due to sFlt-1 present in preeclamptic mothers. The present study is an attempt to interpret rest of the two arms (IRE1 and ATF6) of UPR and ER stress subsequently by in vitro study using BeWo cells after upregulation of master regulator of UPR (GRP78) in placental tissue. Materials and MethodsPart I: Serum analysis of circulating levels of GRP78 and sFlt-1 [in 50 pairs of preeclamptic and normotensive, non-proteinuric (control) pregnant women)] using ELISA. Part II: Correlation analysis of levels of GRP78 and sFlt-1 in preeclamptic and control groups. Part III: Status of expression of GRP78 in placentae (n=10 each, preeclamptic and control groups) was reported using immunofluorescence. Part IV: In vitro experiments using BeWo cells were carried out to analyse the effect of GRP78 and sFlt-1 on IRE1 and ATF6 arms of UPR at protein (immunofluorescence and western blot) and transcript (qRT-PCR) levels. ResultsProtein expressions of GRP78 and sFlt-1 were found significantly elevated in preeclamptic patients as compared to controls. Enhanced expression of master regulator of UPR (GRP78) in placental tissue of preeclamptic women was reported. Up-regulated expression of XBP1 (IRE1 arm) and ATF6 markers of UPR was observed in trophoblast cells. ConclusionThe upregulated expression of GRP78 in preeclamptic placentae and enhanced expression of XBP1 and ATF6 markers in BeWo cells at both protein and transcript levels connote role played by raised circulating levels of GRP78 and sFlt-1 in preeclampsia.

developmental biology↗

bioRxiv2023

Dissociating instructive from permissive roles of brain circuits with reversible neural activity manipulations

Recent work has demonstrated that both permanent lesions and acute inactivation experiments can lead to erroneous conclusions about the causal role of brain areas in specific behaviors, casting serious doubt on major avenues by which neuroscientists study the brain. To overcome this challenge, we developed a three-stage optogenetic approach which leverages the ability to precisely control the temporal period of regional inactivation with either brief or sustained illumination, enabling investigators to dissociate between putative permissive and instructive roles of brain areas in behavior. We applied this approach to the mouse primary visual cortex (V1) to probe whether V1 is permissive or instructive for the detection low contrast stimuli. Acute inactivation of V1 drastically suppressed performance, but during persistent inactivation, the animals contrast detection recovered to pre-silencing levels. This recovery was itself reversible, as returning the animals to intermittent V1 inactivation reinstated the behavioral deficit. These results argue that V1 is the default circuit mice use to detect visual stimuli, but in its absence, other regions can compensate for it. This novel, temporally controllable optogenetic perturbation paradigm should be useful in other brain circuits to assess whether they are instructive or permissive in a brain function or behavior.

neuroscience↗

bioRxiv2023

Abnormal trophoblast invasion in early onset preeclampsia: involvement of cystathionine β-synthase, specificity protein 1 and miR-22

IntroductionImpaired trophoblast invasion has been observed in early onset Preeclampsia patients (EOPE). Trophoblast cell invasion during human placentation is majorly regulated by the balance between MMPs 2, 9 and their inhibitors [tissue inhibitors of matrix metalloproteinases (TIMPs 1, 2)]. Exogenous NaHS (hydrogen sulphide donor) treatment was shown to significantly increase the expression levels of matrix metalloproteinases (MMPs 2, 9) in human bladder cancer EJ cells. Epigentically, the gene expression of hydrogen sulphide synthesising enzyme CBS (cystathionine {beta}-synthase) could be further regulated by various mi-RNAs via the transcription factors like Sp1. Specificity protein 1 (Sp1) has been identified as a target gene for miR-22 to regulate the invasion and metastasis of gastric cancer cells. However, the mechanism of MMPs regulation by either CBS, Sp1 and miRNA-22 in the pregnancies having EOPE is not known. Aims and ObjectivesTo determine and compare the expression of MMPs 2, 9, TIMPs 1, 2, CBS, Sp1 and miRNA-22 in EOPE patients and normotensive, non-proteinuric controls. Materials and methods100 pregnant women were enrolled from Department of Obstetrics and Gynaecology, AIIMS, New Delhi, India. EOPE women (n=50) after clinical diagnosis as per ACOG guidelines were enrolled as cases and normotensive, non-proteinuric pregnant women (n=50) were enrolled as controls. Protocol of the study was approved by Institute Ethics Committee, AIIMS, New Delhi. 5 ml of venous blood was collected from all the recruited women (2.5 ml in each EDTA and sera vial) followed by plasma and sera separation. Plasma samples were used subsequently to determine gene expression of MMPs 2, 9, TIMPs 1, 2, CBS, Sp1 and miRNA-22 by qRT-PCR and sera samples were used to estimate their protein levels by ELISA. Data were analyzed by STATA 14 and Graph Pad Prism 8. ResultsSignificantly down regulated expression of MMPs 2, 9, CBS and Sp1 whereas up regulated expression for that of TIMPs 1, 2 was observed in EOPE patients as compared to healthy pregnant women at both transcription and translation levels. Expression of miR-22 (pre miR-22 and miR-22-3p) was found to be significantly elevated in EOPE patients as compared to normotensive, non-proteinuric controls. ConclusionThis is the very first study of its kind which implicates that down regulated MMPs 2, 9, CBS, Sp1 levels and simultaneously upregulation of miR-22 expression in EOPE patients could have some association. In vitro experiments are needed to prove their association which if proven may provide a new, potential therapeutic target to treat early onset Preeclampsia.

developmental biology↗

bioRxiv2023

MicroRNA-22, Specificity protein-1 and Cystathionine β-synthase in early onset Preeclampsia: significance in trophoblast invasion

IntroductionTrophoblast cell invasion during human placentation is majorly regulated by the balance between MMPs 2, 9 and their inhibitors [tissue inhibitors of matrix metalloproteinases (TIMPs 1, 2)]. Exogenous NaHS (hydrogen sulphide donor) treatment was shown to significantly increase the expression levels of matrix metalloproteinases (MMPs 2, 9) in human bladder cancer EJ cells. Epigentically, the gene expression of hydrogen sulphide synthesising enzyme CBS (cystathionine {beta}-synthase) could be further regulated by various mi-RNAs via the transcription factors like Sp1. Specificity protein 1 (Sp1) has been identified as a target gene for miR-22 to regulate the invasion and metastasis of gastric cancer cells. However, the mechanism of MMPs regulation by either CBS, Sp1 and miRNA-22 in the pregnancies having early onset preeclampsia is not known. Aim of the studyTo determine and compare the expression of MMPs 2, 9, TIMPs 1, 2, CBS, Sp-1 and miR-22 in early onset preeclamptic patients and normotensive, non-proteinuric controls at both transcription and translation levels. Materials and methods30 pregnant women were enrolled from Department of Obstetrics and Gynaecology, AIIMS, New Delhi, India. EOPE women (n=15) after clinical diagnosis as per ACOG guidelines were enrolled as cases and normotensive, non-proteinuric pregnant women (n=15) were enrolled as controls. Protocol of the study was approved by Institute Ethics Committee, AIIMS, New Delhi. 30 caesarean delivered placentae (15 each of patients and controls) were collected to analyse the mRNA and protein expression/levels of MMPs 2, 9, TIMPs 1, 2, CBS, and Sp1. Protein activity of MMP-2 and 9 was determined. Gene expression of miR-22 was observed in placentae of the recruited patients and controls. Data were analysed by STATA 14 and Graph Pad Prism 8. ResultsSignificantly reduced mRNA and protein expression/levels of MMPs 2, 9, CBS and Sp1 whereas elevated for those of TIMP-1 and TIMP-2 was observed in EOPE patients as compared to controls. Gelatinolytic activity of MMP-2 and 9 was also found significantly reduced in placentae from EOPE patients whereas gene expression of miR-22 was found significantly up regulated in the early onset preeclamptic patients in comparison to controls. ConclusionThis is the first study of its kind which implicates that insufficient trophoblastic invasion may be because of down regulation of MMPs 2, 9, CBS, Sp1 and concomitant up regulation of TIMPs 1, 2 and miR-22 in the early onset preeclamptic patients as compared to controls.

developmental biology↗

bioRxiv2023

Role of MicroRNA-22 (miR-22)/Specificity protein 1 (Sp1)/Cystathionine beta-synthase (CBS) axis in regulating trophoblast invasion: an in vitro study

IntroductionPlacenta expresses many ubiquitous as well as specific miRNAs which regulate trophoblast cell differentiation, proliferation, apoptosis, invasion, migration, and angiogenesis. Aberrant miRNAs expression (miR-22) has been linked to pregnancy complications, such as preeclampsia. Specificity protein 1 (Sp1) was identified a direct target of miR-22 and an inverse linear correlation between expression of miR-22 and Sp1 mRNA in gastric tumour has been reported. Also, Sp1 has a critical and indispensable role in the regulation of cystathionine {beta}-synthase (H2S synthesizing enzyme). Exogenous H2S could promote cell proliferation and invasion by upregulating the expression of MMP-2 and MMP-9 in human bladder cancer EJ cells. Worldwide studies reported significant role of MMP-2 and MMP-9 in the regulation of trophoblast invasion. Aims and ObjectivesTo determine the role of MicroRNA-22 (miR-22)/Specificity protein 1 (Sp1)/Cystathionine {beta}-synthase (CBS) axis in regulating trophoblast invasion in the first-trimester trophoblast cells. Materials and methodsThe human first trimester trophoblast cell line (HTR-8/SVneo Cell line) was procured from American Type Culture Collection. Gain/Loss of function studies were conducted on HTR-8/SVneo cells and the expression of miR-22 (pre miR-22 and miR-22-3p), Sp1, CBS, MMP-2 and MMP-9 was observed. Invasion capacity of the cells was assessed by transwell invasion assay. Data were analyzed by STATA 14 and Graph Pad Prism 8. ResultsSignificantly down regulated regulated mRNA and protein expression of Sp1, CBS and and MMPs 2, 9 was observed when the cells were transfected with miR-22-3p mimic in comparison to miR-22-3p inhibitor transfected cells. Expression of CBS and MMPs 2, 9 was found to be significantly up regulated when the cells were transfected with Sp1 plasmid as compared to Sp1 inhibitor (2,4,5 trifluoroaniline) treated cells at both transcription and translation levels. MMP-2 and MMP-9 levels were found to be significantly elevated when the cells were subjected to NaHS [sodium hydrogen sulphide (H2S donor)] treatment as compared to AOAA (aminooxyacetic acid) treated cells. ConclusionThis is the first study which implies that miR-22 via targeting Sp1 must have influenced the mRNA and protein expression of CBS, MMP-2 and MMP-9 in order to regulate the trophoblast invasion.

developmental biology↗

bioRxiv2023

Altered expression of MMP9 and TIMP1 leads to impaired placentation in early onset preeclamptic patients: a case control study

IntroductionMatrix metalloproteinases (MMPs) specifically MMP-9 is a key regulator of vascular and uterine spiral artery remodelling and its activity is controlled at multiple levels, including gene transcription, activation of its latent forms and endogenous inhibition by tissue inhibitors of metalloproteinases [TIMPs (specifically TIMP-1)]. Alteration in MMP-9 and TIMP-1 expression may contribute to uterine and vascular dysfunction leading to adverse pregnancy outcomes such as Preeclampsia (PE). Depending on time, PE is classified as early-onset preeclampsia, which is diagnosed before 34 weeks of gestation, or late-onset preeclampsia, which is diagnosed after 34 weeks. Early-onset preeclampsia (EOPE) is a severe obstetrics disease which threatens mother and foetus. Therefore, in the present study, we aimed to investigate the levels of MMP-9 and its inhibitor TIMP-1 in the placentae of EOPE patients and their maternal age matched normotensive, non-proteinuric controls at both mRNA and protein levels. MethodsA total of 30 caesarean delivered placentae (15 EOPE patients and 15 controls) were collected from Department of Obstetrics and Gynaecology, AIIMS, New Delhi after taking permission from Institute Ethics Committee. MMP-9 and TIMP-1 protein expression was observed by immunohistochemistry and immunofluorescence stainings. Gelatin Gel Zymography was done to evaluate MMP-9 activity and Western Blot was done for the quantification of MMP-9 and TIMP-1 proteins. mRNA levels of MMP-9 and TIMP-1 were determined by qRT-PCR ResultsImmunohistochemistry and Immunofluorescence staining discerned stronger expression of MMP-9 in normotensive placentae as compared to EOPE placentae whereas stronger expression of TIMP-1 was seen in EOPE placentae in comparison to those of normotensive placentae. Gelatin Gel Zymography reflected that MMP-9 activity was found elevated in maternal placental side in normotensive placentae as compared to EOPE placentae. Western Blot analysis revealed that protein expression of MMP-9 was elevated whereas for that of TIMP-1 was reduced in normotensive placentae in comparison to EOPE placentae. mRNA expression of MMP-9 was found up-regulated whereas for that of TIMP-1 was down-regulated in normotensive placentae as compared to EOPE placentae. ConclusionThe present study implies that aberrant functioning of MMP-9 and TIMP-1 in EOPE patients contribute to impaired placentation which might be relevant for possible future screening programs in order to predict and to design therapies for early onset preeclamptic patients.

developmental biology↗

bioRxiv2020

An Hourglass Circuit Motif Transforms a Motor Program via Subcellularly Localized Calcium Signaling in Muscle

Neural control of muscle function is fundamental to animal behavior. Many muscles can generate multiple distinct behaviors. Nonetheless, individual muscle cells are generally regarded as the smallest units of motor control. We report that muscle cells can alter behavior by contracting subcellularly. We previously discovered that noxious tastes reverse the net flow of particles through the C. elegans pharynx, a neuromuscular pump, resulting in spitting. We now show that spitting results from the subcellular contraction of the anterior region of the pm3 muscle cell. Subcellularly localized calcium increases accompany this contraction. Spitting is controlled by an "hourglass" circuit motif: parallel neural pathways converge onto a single motor neuron that differentially controls multiple muscles and the critical subcellular muscle compartment. We conclude that subcellular muscle units enable modulatory motor control and propose that subcellular muscle contraction is a fundamental mechanism by which neurons can reshape behavior.

neuroscience↗

bioRxiv2018

sFlt-1 commutes unfolded protein response into endoplasmic reticulum stress in trophoblast cells in preeclamptic pregnancies

Preeclampsia (PE) and its subtypes (early and late onset) are serious concerns all across the globe affecting about 8% of total pregnancies and accounts for approximately 60,000 deaths annually with a predominance in developing under-developed and countries. The two-stage model in the progression of this disease, deficient spiral artery remodelling and an imbalance between angiogenic (VEGF) and anti-antigenic factor(s) (sFlt-1) are well established facts pertaining to this disease. The presence of increased sFlt-1, high oxidative stress and Endoplasmic reticulum stress (ER stress) have been proposed in preeclamptic pregnancies. Recently, the role of endoplasmic reticulum stress in the onset of the variant forms of PE highlighted a new window to explore further. In our previous studies, we demonstrated that sFlt-1 can induce apoptosis and oxidative stress in trophoblast cells. However the role of sFlt-1, in inducing ER stress is not known so far. In the present study, we for the first time demonstrated significant ER stress in the placental cells (BeWo Cells) (in vitro) when exposed to sera from preeclamptic pregnancies having increased concentration of sFlt-1. The expression of ER stress markers (GRP78, eIF2, XBP1, ATF6 and CHOP) at both transcript and protein levels were compared (between preeclamptic and normotensive non-proteinuric women) at three different time points (8h, 14h and 24hrs), analyzed and found to be significant (p<0.05).\n\nConclusionOur results suggested that sFlt-1, released from placental cells in preeclampsia may be one of the various factors having potential to induce endoplasmic reticulum stress in BeWo cells.

developmental biology↗

bioRxiv2017

sFlt-1 (sVEGFR1) induces placental endoplasmic reticulum stress in trophoblast cell: implications for the complications in preeclampsia - an in vitro study

BackgroundThe concentration of sFlt-1, a major anti-angiogenic protein in maternal circulation has been seen to be raised in preeclamptic pregnancies. Endoplasmic reticulum (ER) stress represents one of the three (immunological, oxidative and ER stress) major stresses which placenta undergoes during pregnancies. The present study is designed to investigate the role of sFlt-1 in induction of ER stress in trophoblast cells.\n\nMaterials and MethodsMaternal serum levels of anti-angiogenic protein sFlt-1 and central regulator of unfolded protein response GRP78 was measured using sandwich ELISA. The expression of various ER stress markers (GRP78, eIF2, XBP1, ATF6 and apoptotic protein CHOP) were analyzed depending on various treatments given to the trophoblast cells using Immunofluorescence, western blot and q-RT PCR.\n\nResultsIncreased expression of ER stress markers (GRP78, eIF2, XBP1 ATF6 and apoptotic protein CHOP) was detected in the placental trophoblast cells treated with raised concentration of sFlt-1.\n\nConclusionSignificant upregulated expression of ER stress markers in trophoblast cells exposed with increased concentration of sFlt-1 suggested that it may be one of the anti-angiogenic factors present in maternal sera which not only contributes to oxidative stress but also may cause endoplasmic reticulum stress.

developmental biology↗