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Mediator 25 (Med25) is a member of the mediator complex that relays signals from transcription factors to the RNA polymerase II machinery. Multiple transcription factors, particularly those involved in lipid metabolism, utilize the mediator complex, but how Med25 is involved in this context is unclear. We previously identified Med25 in a translatome screen of adult cardiomyocytes (CMs) in a novel cell type-specific model of LMNA cardiomyopathy. In this study, we show that Med25 upregulation is coincident with myocardial lipid accumulation. To ascertain the role of Med25 in lipid accumulation, we utilized iPSC-derived and neonatal CMs to recapitulate the in vivo phenotype by depleting lamins A and C (lamin A/C) in vitro. Although lamin A/C depletion elicits lipid accumulation, this effect appears to be mediated by divergent mechanisms dependent on the CM developmental state. To directly investigate Med25 in lipid accumulation, we induced adipogenesis in Med25-silenced 3T3-L1 preadipocytes and detected enhanced lipid accumulation. Assessment of pertinent mediators driving adipogenesis revealed that C/EBPα and PPARγ are super-induced by Med25 silencing. Our results indicate that Med25 limits adipogenic potential by suppressing the levels of master regulators that govern adipogenesis. Furthermore, we caution the use of early-developmental-stage cardiomyocytes to model adult-stage cells, particularly for dissecting metabolic perturbations emanating from LMNA mutations.

Objective Measurement of total vitamin B12 (vit B12) concentration raised concerns over early detection of vit B12 deficiency due to its clinical unreliability. In this present article we aimed to assess the efficacy of active vit B12 for the detection of true vit B12 deficiency. This retrospective study included 100 participants referred for vit B12 assay. Serum total vit B12, active vit B12 and homocysteine were estimated. Results Our study showed 59% of the total participants with vit B12 deficiency (185 ± 64.62 pg/ml) and 18% with hyper-cobalaminemia (1666.9 ± 367.13 pg/ml) based on their total vit B12 concentrations. A comparative study on total vit B12 and active vit B12 was done which reflected a striking disparity in results. Active vit B12 reported 28.8% patients with vit B12 deficiency (19.8 ± 17.48 pg/ml) and only 16.6% patients with hyper-cobalaminemia (224.14 ± 10 pg/ml). Active vit B12 appeared to be more sensitive (82.35%vs 65%) and specific (46.6% vs 43.8%) diagnostic marker compared to total vit B12. Pearson Correlation study indicated a strong positive correlation (r = 0.695 at p

Obg proteins belong to P-loop guanine triphosphatase (GTPase) that are conserved from bacteria to humans. Like other GTPases, Obg cycles between guanine triphosphate (GTP) bound "on" state and guanine diphosphate (GDP)-bound "off" state, thereby controlling various cellular processes. Different members of this group have unique structural characteristics; a conserved glycine-rich N-terminal domain known as obg fold, a central conserved nucleotide binding domain, and a less conserved C-terminal domain of other functions. Obg is a ribosome dependent GTPase helps in ribosome maturation by interacting with several proteins of the 50S subunit of the ribosome. Obg proteins have been widely considered as a regulator of cellular functions, helping in DNA replication, cell division. Apart from that, this protein also takes part in various stress adaptation pathways like a stringent response, sporulation, and general stress response. In this particular review, the structural features of ObgE have been highlighted and how the structure plays important role in interacting with regulators like GTP, ppGpp that are crucial for executing biological function has been orchestrated. In particular, we believe that Obg-like proteins can provide a link between different global pathways that are necessary for fine-tuning cellular processes to maintain the cellular energy status.

Mutations in the LMNA gene, encoding lamins A and C (lamin A/C) cause a diverse group of human diseases termed laminopathies. The most prevalent laminopathy is dilated cardiomyopathy (herein referred to as LMNA cardiomyopathy) characterized by variable onset of fibrosis/pathological remodeling that always progresses to heart failure. Despite recent progress, how cell type-specific effects of LMNA mutations are integrated at the tissue level to engender complex pathologies in a heterocellular organ such as the heart are not well understood. Using a conditional deletion model that permits cardiomyocyte (CM)-specific Lmna deletion coupled with translating ribosome affinity purification, we found that CM-specific lamin A/C depletion caused rapid fibrosis and severe cardiac dysfunction accompanied by endoplasmic reticulum (ER) stress. At the molecular level, CM-specific translating mRNA profiling identified increased expression of MED25, a member of the Mediator complex implicated in regulating ER stress responses, prior to the onset of cardiac dysfunction. In contrast, lamin A/C depletion selectively in cardiac fibroblasts (CFs) displayed no immediate cardiac pathology whereas a concurrent depletion in both CMs and CFs resulted in lesser fibrosis and pathological remodeling. These results suggest that lamin A/C play an important role in CF biology and that reactive CFs underlie the rapid onset and the exaggerated LMNA cardiomyopathy symptoms observed in mice with CM-only Lmna deletion. Mechanistically, we found that increased matrix stiffness elevated the expression of MED25 and ER stress markers in lamin A/C-depleted CMs in vitro , indicating that the physical component of fibrosis may underlie the observed molecular changes. Taken together, our results suggest lamin A/C-depleted CFs mediate a brake on cardiomyopathy development and interactions between CFs and CMs are important determinants of the rate of progression and the severity of LMNA cardiomyopathy. Therefore, strategies targeting lamin A/C function in CFs may hold therapeutic potential for patients with LMNA cardiomyopathy as well as for other forms of cardiomyopathy in which fibrosis is integral to disease pathogenesis.

The molecular pathways activated in response to acute cathepsin G (CG) exposure, as well as the mechanisms involved in activation of signaling pathways that culminate in myocyte detachment and apoptosis remain unclear. This study aimed to determine the changes in gene expression patterns associated with time dependent CG exposure to neonatal rat cardiomyocytes (NRCMs). Microarray analysis revealed a total of 451, 572 and 1127 differentially expressed genes after CG exposure at 1, 4 and 8 h respectively. A total of 54 overlapped genes at each time point were mapped by Ingenuity Pathway Analysis (IPA). The top up-regulated genes included Hamp, SMAD6, NR4A1, FOSL2, ID3 and SLAMF7, and down-regulated genes included CYR61, GDF6, Olr640, Vom2r36, DUSP6 and MMP20. Our data suggest that there are multiple deregulated pathways associated with cardiomyocyte death after CG exposure, including JAK/Stat signaling, IL-9 signaling and Nur77 signaling. In addition, we also generated the molecular network of expressed gene and found most of the molecules were connected to ERK1/2, caspase, BCR (complex) and Cyclins. Our study reveals the ability to assess time-dependent changes in gene expression patterns in NRCMs associated with CG exposure. The global gene expression profiles may provide insight into the cellular mechanism that regulates CG dependent myocyte apoptosis. In future, the pathways important in CG response, as well as the genes found to be differentially expressed might represent the therapeutic targets for myocyte survival in heart failure.

Radioprotective action of gossypetin (GTIN) against gamma (γ)-radiation-induced oxidative stress in liver was explored in the present article. Our main aim was to evaluate the protective efficacy of GTIN against radiation-induced alteration of liver in murine system. To evaluate the effect of GTIN, it was orally administered to mice at a dose of 30 mg/kg body weight for three consecutive days prior to γ-radiation at a dose of 5 Gy. Radioprotective efficacy of GTIN were evaluated at physiological, cellular, and molecular level using biochemical analysis, comet assay, flow cytometry, histopathology, immunofluorescence, and immunoblotting techniques. Ionizing radiation was responsible for augmentation of hepatic oxidative stress in terms of lipid peroxidation and depletion of endogenous antioxidant enzymes. Immunoblotting and immunofluorescence studies showed that irradiation enhanced the nuclear translocation of nuclear factor kappa B (NF-κB) level, which leads to hepatic inflammation. To investigate further, we found that radiation induced the activation of stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK)-mediated apoptotic pathway and deactivation of the NF-E2-related factor 2 (Nrf2)-mediated redox signaling pathway, whereas GTIN pretreatment ameliorated these radiation-mediated effects. This is the novel report where GTIN rationally validated the molecular mechanism in terms of the modulation of cellular signaling system’ instead of ‘ This is the novel report where GTIN is rationally validated in molecular terms to establish it as promising radioprotective agents. This might be fruitful especially for nuclear workers and defense personnel assuming the possibility of radiation exposure.

Diabetes increases the risk of Cardio-vascular disease (CVD). CVD is more prevalent in type 2 diabetes (T2D) than type 1 diabetes (T1D), but the mortality risk is higher in T1D than in T2D. The pathophysiology of CVD in T1D is poorly defined. To learn more about biological pathways that are potentially involved in T1D with cardiac dysfunction, we sought to identify differentially expressed genes in the T1D heart. Our study used T1D mice with severe hyperglycemia along with significant deficits in echocardiographic measurements. Microarray analysis of heart tissue RNA revealed that the T1D mice differentially expressed 10 genes compared to control. Using Ingenuity Pathway Analysis (IPA), we showed that these genes were significantly involved in ketogenesis, cardiovascular disease, apoptosis and other toxicology functions. Of these 10 genes, the 3-Hydroxy-3-Methylglutaryl-CoA Synthase 2 (HMGCS2) was the highest upregulated gene in T1D heart. IPA analysis showed that HMGCS2 was center to many biological networks and pathways. Our data also suggested that apart from heart, the expression of HMGCS2 was also different in kidney and spleen between control and STZ treated mice. In conclusion, The HMGCS2 molecule may potentially be involved in T1D induced cardiac dysfunction.

The present study demonstrates for the first time the protective role of two common flavonoids, quercetin and its glycone rutin, against high cholesterol diet (2%) induced hepatotoxicity and inflammation. Swiss albino mice were given either a standard laboratory diet (control), high cholesterol diet (HCD) or high cholesterol diet along with quercetin or rutin (100 mg kg−1 body weight) in their respective groups. The HCD mice exhibited a gain in body weight, significant rise in serum and hepatic level of total cholesterol, triglyceride, liver function enzymes, lipid peroxidation, and pro-inflammatory cytokines (P < 0.05). Histopathological studies showed hepatic fat accumulation and tissue disintegration. There was significant depletion of major hepatic antioxidants (P < 0.05). Immunoblot studies revealed a high expression of redox sensitive transcription factors NF-κB and TNF-α. A subsequent rise in the mRNA expression of inflammatory markers like C reactive protein and inducible nitric oxide synthase 2 were also found from the RT-PCR study. Simultaneous treatment with quercetin or rutin along with HCD significantly prevented the gains in body weight, lipid level, liver function enzymes, lipid peroxidation level and expression of inflammatory markers. The restoration of hepatic antioxidant homeostasis and hepatic morphology has also been observed. Hence, the present study illustrates the hypolipidemic, hepatoprotective and anti-inflammatory effects of two similar flavonoids.

High fat diet group showed a significant rise in serum and hepatic total cholesterol, triglyceride and atherogenic index which are major biomarkers of dyslipidemia and cardiovascular risk. The liver function markers, lipid peroxidation and proinflammatory cytokine levels were elevated in high fat diet group whereas antioxidant levels significantly reduced. These findings manifest hepatic damage which was further confirmed by histological findings. Quercetin and beta-sitosterol though structurally different yet both ameliorate the sickening changes in different mechanism. The current investigation is perhaps the first report of the mechanistic role of two polyphenols over dyslipidemia and subsequent hepatotoxicity.

Aims The present study evaluated a comparative and combined hepatoprotective effect of atorvastatin (AS) and ferulic acid (F) against high fat diet (HFD) induced oxidative stress in terms of hyperlipidemia, anti-oxidative status, lipid peroxidation and inflammation. Main methods Male Swiss albino mice were given a diet containing high fat (H) (23.9% wt/wt), supplemented with AS (10 mg/kg) or F (100 mg/kg) and both (10 and 100 mg/kg) for 8 weeks. The control mice (C) were fed with normal diet. Key findings The H mice exhibited increased body weight; hyperlipidemia; serum level of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6); hepatic lipid profile; lipid accumulation; reactive oxygen species (ROS) of hepatocytes, lipid peroxidation and liver antioxidant capacity was decreased. Immunofluorescent and Western blot assay revealed activation of nuclear factor kappa B (NF-κB) signaling pathway. The addition of F or AS and both in the diet significantly counteracted HFD induced body weight gain; hyperlipidemia; TNF-α, IL-6; hepatic lipid profile; fatty infiltration; NF-κB signaling pathway; ROS; lipid peroxidation and moreover elevated levels of hepatic antioxidant enzymes activity were observed. Significance Simultaneous treatment with AS, F and their combination protected against HFD induced weight gain and oxidative stress. The protection may be attributed to the hypolipidemic and free radical scavenging activity of AS or F and their combination. This study illustrates that AS and F have relatively similar hypolipidemic, antioxidative, anti-inflammatory actions and the AS + F combination along with HFD has shown outstanding effects as compared to other treated groups.

Consumption of high-fat diet (HFD) induces nonalcoholic fatty liver disease (NAFLD) and may lead to multiple complications affecting human health. In the present study, effect of Moringa oleifera leaf extract (MoLE) in alleviating HFD induced liver injury in mice has been reported. Liver histology and serum activity of hepatic marker enzymes i.e. aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) have been studied. Lipid peroxidation (LPO), ferric reducing antioxidant power (FRAP) and reduced glutathione (GSH) were also estimated using liver homogenate. Results of the study suggested that MoLE treatment protected HFD-induced liver damage as indicated by histopathology and liver enzyme activity compared to only-HFD fed group (P0.05). Interestingly, early signs of HFD-induced fatty liver were also alleviated by MoLE. Moreover, significant increase in endogenous antioxidant parameters and lower lipid peroxidation were found in liver of all MoLE treated groups. Results of the study indicated that MoLE has both preventive as also curative hepatoprotective activity.

Consumption of a high-fat diet (HFD) promotes reactive oxygen species (ROS) which ultimately trigger inflammation. The aim of this study was to investigate the role of Moringa oleifera leaf extract (MoLE) and its active component quercetin in preventing NF-κB-mediated inflammation raised by short-term HFD. Quercetin was found to be one of the major flavonoid components from HPLC of MoLE. Swiss mice were fed for 15 days on HFD, both with or without MoLE/quercetin. The antioxidant profile was estimated from liver homogenate. NF-κB and some relevant inflammatory markers were evaluated by immunoblotting, RT-PCR and ELISA. Significantly (P < 0.05) lower antioxidant profile and higher lipid peroxidation was found in HFD group compared to control (P < 0.05). Increased nuclear import of NF-κB and elevated expressions of pro-inflammatory markers were further manifestations in the HFD group. All these changes were reversed in the MoLE/quercetin-treated groups with significant improvement of antioxidant activity compared to the HFD group. MoLE was found to be rich in polyphenols and both MoLE and quercetin showed potent free radical and hydroxyl radical quenching activity. Thus, the present study concluded that short-term treatment with MoLE and its constituent quercetin prevent HFD-mediated inflammation in mice.