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Background: ANGPTL8 has been recently identified as lipid metabolism and inflammation regulator. It interacts with ANGPTL3 and, more recently, ANGPTL4 to regulate LPL activity. It was also shown to modulate NF-κB activity through its interaction with ikkα/β. A genetic variant rs2278426 (R59W) in ANGPTL8 has been associated with reduced LDL and HDL in Hispanics and increased FBG in Arabs. The objective of the study was to investigate the impact of the R59W variant on LPL and the inflammatory activity of ANGPTL8. Methods: ANGPTL8 was genotyped in a discovery cohort of 738 Kuwaiti individuals. ANGPTL8 level, as well as inflammatory markers and LPL, were measured in plasma. Additionally, metabolite analysis, overexpression, luciferase binding assay, confocal microscopy, and cellular fractionation analyses were conducted in the HepG2 cell line to assess differences between the ANGPTL8 and its variant. Results: The ANGPTL8 rs2278426 variant was associated with an increase in circulatory levels of TNF-α and IL7 in our cohort. Carrier versus reference genotype of the studied variant showed differences in the following metabolites: Acylcarnitines, Phosphatidylcholine, and Cholesteryl Ester. These metabolites are implicated in modulating NF-κB and TNF-α levels. Our in vitro analyses showed that the activity levels of NF-κB p65 was higher in the R59W than the wild type, and it was further elevated with TNFα stimulations. The data was validated by the luciferase activity, confocal microscopy, and cellular fractionation. Conclusion: This study showed that ANGPTL8 variant R59W is associated with increased circulatory TNF-α and IL7 levels but not the LPL plasma levels. We have also demonstrated the pro-inflammatory role of the R59W variant in regulating the NF-κB pathway as reflected by genotyping, in vitro, metabolomics, and structural analyses. Further studies are needed to expand our understanding of other signaling pathways and possible crosstalk in the context of inflammation. Disclosure A.Mohammad: None. A.T.Thangavel: None. F.Almulla: None. J.Abubaker: None. M.Abu-farha: None. D.Madhu: None. P.T.Cherian: None. I.Al khairi: None. P.Hebbar: None. S.A.Kavalakatt: None. H.Arefanian: None. N.Alam-eldin: None. Funding Kuwait Foundation for the Advancement of Sciences

Melanocortin 4 receptor (MC4R) has a well-established role in regulating appetite, food intake and energy homeostasis. Setmelanotide is an MC4R agonist currently approved for weight loss in obese adults and children with mutations in components of the leptin-melanocortin pathway. This study aims to compare structural and functional aspects of the physiological MC4R agonist α-melanocyte-stimulating hormone (α-MSH) with setmelanotide. We also aim to show the binding affinity of setmelanotide to known MC4R human missense mutations associated with obesity.AutoDock Vina was used in the structural analysis to calculate induced fit docking scores of ligand binding to MC4R wild type or the selected variants. HEK293-MC4R were utilized in the functional analysis of MC4R-actiavted pathways upon stimulating with α-MSH or setmelanotide.Our data shows that setmelanotide has a higher potency for cAMP formation and a weaker effect on ERK1/2 phosphorylation when compared to α-MSH indicating functional selectivity otherwise known as biased agonism. We also present structural data showing that setmelanotide has a higher binding affinity to MC4R compared to α-MSH. Lastly, we show that two loss-of-function and two gain-of-function MC4R variants change the conformation not only of the ligand binding pocket of the receptor but also of the peptide when bound to the receptor because the interaction network and the residues involved in the binding are altered.Taken together, our study provides important insights into the diversity of MC4R signaling pathways which will facilitate the development of personalized anti-obesity drugs via refining MC4R agonists.

Background Angiopoietin-like proteins (ANGPTL), primarily 3, 4, and 8, play a major role in maintaining energy homeostasis by regulating triglyceride metabolism. This study evaluated the level of ANGPTL3, 4, and 8 in the liver, brown adipose tissue (BAT), and subcutaneous white adipose tissue (SAT) of mice maintained under acute and chronic cold conditions. Methods C57BL/6J mice were exposed to cold temperature (4 °C) for 10 days with food provided ad libitum. Animal tissues were harvested at Day 0 (Control group, n = 5) and Days 1, 3, 5, and 10 (cold treatment groups, n = 10 per group). The expression levels of various genes were measured in the liver, SAT, and BAT. ANGPTL3, 4, and 8 expressions were measured in the liver. ANGPTL4, 8, and genes involved in browning and lipid metabolism [uncoupling protein 1 (UCP1), lipoprotein lipase (LPL), and adipose triglyceride lipase (ATGL)] were measured in SAT and BAT. Western blotting (WB) analysis and immunohistochemistry (IHC) were performed to confirm ANGPTL8 expression in these tissues. Results The expressions of ANGPTL3 and 8 mRNA were significantly reduced in mouse liver tissues after cold treatment (P P ANGPTL8 gene expression exhibited over a 5-fold increase. Similarly, UCP1 gene expression was also significantly increased in SAT. The mRNA levels of LPL and ATGL showed an initial increase followed by a gradual decrease with an increase in the days of cold exposure. ANGPTL8 protein overexpression was further confirmed by WB and IHC. Conclusions This study shows that exposure to acute and chronic cold treatment results in the differential expression of ANGPTL proteins in the liver and adipose tissues (SAT and BAT). The results show a significant reduction in ANGPTL4 in BAT, which is linked to improved thermogenesis in response to acute cold exposure. ANGPTL8 was activated under acute and chronic cold conditions in SAT, suggesting that it is involved in regulating lipolysis and enhancing SAT browning.

Sikkim, one of the Northeastern states of India, is a famous tourism spot in the Himalayas with dynamic population density. This mountainous area receives heavy rainfall and is well known for frequent shallow landslides, especially, Chandmari, which is a village, situated in Gangtok area in East Sikkim. Even though it is well known that rainfall and landslides are correlated, Sikkim lacks a well-established landslide early warning system. Such a system is important in this region because it is one of the highest landslide-prone areas in India. The current research attempts to establish rainfall thresholds as part of developing an efficient landslide early warning system for this region. The rainfall thresholds for landslides are derived based on the daily rainfall data available from India Meteorological Department (IMD) for six stations in Sikkim. Analysis of daily rainfall data and landslide events in this area between the year 1990 and 2017 is performed. An intensity–duration (I–D)-based regional rainfall threshold is derived as I = 43.26 D−0.78 (I = rainfall intensity in mm/day and D = duration in days) for the rainfall-triggered landslides in Sikkim region and a local threshold of I = 100 D−.92 was developed for the Gangtok area. Furthermore, the influence of antecedent rainfall in landslide initiation is explored by considering the daily, 3-day, 5-day, 7-day, and 20-day cumulative rainfall values associated with landslides. The proposed threshold equations and study of the effect of antecedent rainfall on landslides are intended to aid in enhancing the real-time landslide early warning system (R-LEWS) being developed for Sikkim.

The human Receptor for Advanced Glycation End Products (hRAGE) is a pattern recognition receptor implicated in inflammation and adhesion. It is involved in both innate and adaptive immunity. Its aberrant signaling is tied to the pathogenesis of diabetic complications, neurodegenerative disorders, and chronic inflammatory responses. Previous structural studies have focused on its extracellular domains with their canonical constant and variable Ig folds, and to a much lesser extent, the intrinsically disorder cytoplasmic domain. No experimental data are reported on the transmembrane domain, which is integral to signaling. We have constructed, expressed and purified the transmembrane domain attached to the cytoplasmic domain of hRAGE in E. coli. Multiple self-associated forms of these domains were observed in vitro. This pattern of mixed oligomers resembled previously reported in vivo forms of the complete receptor. The self-association of these two domains was further characterized using: SDS-PAGE, intrinsic tryptophan fluorescence and heteronuclear NMR spectroscopy. NMR conditions were assessed across time and temperature within micelles. Our data show that the transmembrane and cytoplasmic domains of hRAGE undergo dynamic oligomerizations that can occur in the absence of its extracellular domains or ligand binding. And, such associations are only partially disrupted even with prolonged incubation in strong detergents.

Normalized Difference Vegetation Index (NDVI) is a measure of vegetation productivity and health. Many previous studies have established its utility in understanding the changes that happen to vegetated regions. Temperature and precipitation are closely associated with the vegetation quantity and quality in a place. Natural variability in climate along with human interactions have profound influence on this. Sustaining the natural ecosystem of a region requires understanding these interactions. Remote sensing systems provide valuable measurements to study changes in the various environmental factors and provide a means for observing regions that are not easily reachable using ground-based techniques alone. The state of Kerala is witnessing big changes in its climate pattern in the recent times. Disastrous phenomena like recurring floods and hazards like landslides are posing threats to plants and trees along with human lives and livelihoods. In addition to these climate-based changes, we are also witnessing modifications to our natural ecosystem due to man-made constructions and such activities. Both the natural and man-made modifications may have far reaching consequences for the environment as a whole and plant life specifically. The current study investigates the spatial and temporal variability of NDVI over Kerala. Estimation of NDVI is performed using the NIR and visible bands of Landsat-8 satellite. This study analyses the observed variability in NDVI using remote sensing observations without looking into the underlying causes and mechanisms that might have led to it.

Lipotoxicity, an important factor in the pathogenesis of diabetes, leads to defective β-cell proliferation and increased apoptosis. Glucagon-like peptide-1 (GLP-1) analogs, which are used to treat type 2 diabetes, reduce endoplasmic reticulum stress and inflammation in pancreatic β-cells and improve their survival. However, their effects on the heat shock response (HSR) have not been elucidated yet. We investigated whether the GLP-1 analog exendin-4 exerts its protective effect by modulating the HSR and mitogen-activated protein kinases (MAPKs) in BTC-6 mouse pancreatic cells under palmitic acid (PA) stress. Expression patterns were analyzed using mass spectrometry, Western blotting, and qRT-PCR in the presence of 250 or 400 μM PA and 100 nM exendin-4. Additionally, we measured MAPK expression and phosphorylation using qRT-PCR and Western blotting, respectively. Upregulation of heat shock protein (HSP), notably HSP72, in the presence of PA, was attenuated by exendin-4. Despite the absence of global effects on the HSR system, exendin-4 attenuated the expression of other non-classical HSPs (GRP94, DNAJA1, and DNAJB6) in the presence of PA. Regarding MAPKs, only extracellular signal-regulated kinase (ERK) phosphorylation was highly increased by exendin-4 in both the presence and absence of PA. Furthermore, exendin-4 significantly alleviated PA-induced cell death, which was further confirmed with proteomics analysis where key cellular functions, including cellular growth, assembly, and organization, were improved by exendin-4 treatment. Thus, our results expand the protective role of GLP-1 analogs to include other cellular mechanisms involved in restoring normal β-cell homeostasis.

Heavy rainfall inducing other catastrophic events are frequently experienced globally. Understanding the mechanisms of moisture transport during such events will help in furthering our knowledge about such systems. In the current study, estimation of most likely moisture trajectoriesis performed using back trajectory analyses. Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model available from National Oceanic and Atmospheric Administration’s (NOAA) Air Resources Laboratory (ARL) is used for the purpose. A preliminary analysis is conducted by calculating the frequencies of back trajectories from two locations in Kerala for three heavy rainfall cases. The analysis indicates that both the locations have similar pattern of moisture trajectories during the cases occurring in south west monsoon and pre monsoon periods. However, a change in the behaviour of the trajectories for the two locations is observed for the case during the north east monsoon period. Since this study involved only individual cases, robust conclusions cannot be made based on this for the dynamics of moisture transport for these locations. More detailed analysis will follow this preliminary study in future for the purpose.

Background and objectives Perturbation of the endoplasmic reticulum (ER) homeostasis has emerged as one of the prominent features of obesity and diabetes. This occurs when the adaptive unfolded protein response (UPR) fails to restore ER function in key metabolic tissues. We previously reported increased inflammation and impaired heat shock response (HSR) in obese human subjects that were restored by physical exercise. Here, we investigated the status of ER stress chaperone; glucose-regulated protein 78 (GRP78) and its downstream UPR pathways in human obese, and their modulation by a supervised 3-month physical exercise. Methods Subcutaneous adipose tissue (SAT) and blood samples were collected from non-diabetic adult human lean (n = 40) and obese (n = 40, at baseline and after 3 months of physical exercise). Transcriptomic profiling was used as a primary screen to identify differentially expressed genes and it was carried out on SAT samples using the UPR RT 2 Profiler PCR Array. Conventional RT-PCR, immunohistochemistry, immunofluorescence, Western blot and ELISA were used to validate the transcriptomic data. Correlation analyses with the physical, clinical and biochemical outcomes were performed using Pearson's rank correlation coefficient. Results Levels of GRP78 and its three downstream UPR arms; activating transcription factor-6 (ATF6), inositol-requiring enzyme-1α (IRE1α) and protein kinase RNA-like endoplasmic reticulum kinase (PERK) were increased in obese subjects. More interestingly, higher levels of circulating GRP78 protein were found in obese compared to lean subjects which correlated negatively with maximum oxygen uptake (V O2 Max ) but positively with high-sensitivity C-reactive protein (hsCRP) and obesity indicators such as BMI, percentage body fat (PBF) and waist circumference. GRP78 increased secretion in obese was further confirmed in vitro using 3T3-L1 preadipocyte cells under ER stress. Finally, we showed that physical exercise significantly attenuated the expression and release of GRP78 with a concomitant reduction in the phosphorylation of IRE1α and eukaryotic initiation factor-2α (eIF2α). Conclusion Our results suggest that physical exercise alleviates ER stress in human obese through attenuation of GRP78 signaling network.

Cardiovascular disease (CVD) risks persist in patients despite treatment. CVD susceptibility also varies with sex and ethnicity and is not entirely explained by conventional CVD risk factors. The aim of the present study was to identify novel CVD candidate markers in circulating Peripheral blood mononuclear cells (PBMCs) and plasma from Arab obese subjects with and without CVD using proteomic approaches. Human adults with confirmed CVD (n = 208) and matched non-CVD controls (n = 152) living in Kuwait were examined in the present cross-sectional study. Anthropometric and classical biochemical parameters were determined. We employed a shotgun proteomic profiling approach on PBMCs isolated from a subset of the groups (n = 4, each), and differentially expressed proteins selected between the two groups were validated at the mRNA level using RT-PCR (n = 6, each). Plasma levels of selected proteins from the proteomics profiling: Proteinase-3 (PR3), Annexin-A3 (ANX3), Defensin (DEFA1), and Matrix Metalloproteinase-9 (MMP9), were measured in the entire cohort using human enzyme-linked immunosorbent assay kits and were subsequently correlated with various clinical parameters. Out of the 1407 we identified and quantified from the proteomics profiling, 47 proteins were dysregulated with at least twofold change between the two subject groups. Among the differentially expressed proteins, 11 were confirmed at the mRNA levels. CVD influenced the levels of the shortlisted proteins (MMP9, PR3, ANX3, and DEFA1) in the PBMCs and plasma differentially. Despite the decreased levels of both protein and mRNA in PBMCs, PR3 circulating levels increased significantly in patients with CVD and were influenced by neither diabetes nor statin treatment. No significant changes were; however, observed in the DEFA1, MMP9, and ANX3 levels in plasma. Multivariate logistic regression analysis revealed that only PR3 was independently associated with CVD. Our results suggest that the dysregulation of PR3 levels in plasma and PBMCs reflects underlying residual CVD risks even in the treated population. More prospective and larger studies are required to establish the role of PR3 in CVD progression.

Table S1. Physical, biochemical and clinical characteristics of the diabetic group based on HbA1c levels. (DOCX 16 kb)

Figure S2. Adiponectin levels and effect of exercise on the subcutaneous adipose tissue (SAT) of obese subjects with and without diabetes. Immunofluorescence analysis of adiponectin expression in SAT from obese subjects with and without diabetes before and after a 3-month physical exercise intervention (n = 10 for each group). Data were quantified as detailed in the Materials and Methods section. The p value was determined using Mann–Whitney test for comparisons between the diabetes and non-diabetes groups and using a paired t-test for intragroup comparisons before and after exercise. * p

Table S2. Physical, clinical and biochemical characteristics of the non-diabetic group based on MHO and MUO classification. (DOCX 18 kb)

Figure S3. Immunofluorescent analysis of fetuin-A levels in the subcutaneous adipose tissue (SAT) of lean subjects with and without diabetes. (A) Confocal microscopy showing fetuin-A abundance and localisation in vesicular-like structures in the thin rim of the cytoplasm of SAT collected from lean subjects with and without diabetes. (B) Representative confocal immunofluorescence images illustrating fetuin-A and adiponectin abundance in SAT from lean subjects with and without diabetes (n = 3 for each group). (PPTX 224 kb)

Table S3. Effect of exercise and diabetes and their combination on the characteristics of the study population. (DOCX 23 kb)

Table S4. Primer sequences used for quantitative real time PCR to analyze fetuin-A and GAPDH gene expression status. (DOCX 13 kb)

Figure S1. Correlation analysis. Correlation of circulating fetuin-A with HbA1c, TG, HDL and FBG were assessed in the whole population using Spearmanâ s rank correlation coefficient. (PPTX 161 kb)

Purpose : Glucagon-like peptide-1 (GLP-1) analogues reduce ER stress and inflammation in key metabolic organs, including the liver. However, their effects on heat shock response (HSR) and mitogen-activated protein kinases (MAPKs) have not yet been elucidated. In the present study, we investigated whether the GLP-1 analogue, exendin-4, triggers the expression of HSR and increases MAPK activity under metabolic stress. Experimental design : The effects of exendin-4 in the presence or absence of palmitic acid (PA; 400 μM) or glucose (30 mM) in the HepG2 liver cell line were assessed using Western blots, quantitative real-time PCR and label-free proteomics. Results : Heat shock proteins (HSP60, HSP72, HSP90 and GRP78) and other chaperones were not significantly affected by exendin-4 under the conditions tested. In contrast, the presence of exendin-4 alone increased the MAPK phosphorylation levels (JNK, ERK1/2 and p38). For short incubation periods, in the presence of PA or glucose, treatment with exendin-4 exhibited limited effects but significantly attenuated MAPK phosphorylation after a 24-h incubation. Interestingly, canonical signalling pathways, such as EIF2, ILK, PKA and Rho, were modulated by exendin-4. Conclusion and clinical relevance : Identifying new pathways modulated by GLP-1 analogues will provide further insights into their benefits beyond their currently recognized roles in glycaemic control, such as MAPK activity, energy homeostasis and body weight decrease. This article is protected by copyright. All rights reserved

Objective ANGPTL7 is a member of the Angiopoietin-like (ANGPTL) protein family that is composed of eight proteins (1-8). Increasing evidence is associating ANGPTL proteins to obesity and insulin resistance. The biological role of ANGPTL7 is yet to be understood except for a recently proposed role in the pathophysiology of glaucoma. This study was designed to shed light on the function of ANGPTL7 in obesity and its modulation by physical exercise as well as its potential association with lipid profile. Methods A total of 144 subjects were enrolled in this study and finished three months of physical exercise. The participants were classified based on their BMI, 82 subjects were non-obese and 62 obese. ANGPTL7 levels in plasma and adipose tissue were measured by ELISA, RT-PCR and immunohistochemistry. Results In this study, we showed that ANGPTL7 level was increased in the plasma of obese subjects (1249.05± 130.39 pg/mL) as compared to non-obese (930.34 ± 87.27 pg/mL) (p-Value = 0.032). ANGPTL7 Gene and protein expression levels in adipose tissue also showed over two fold increase. Physical exercise reduced circulating level of ANGPTL7 in the obese subjects to 740.98± 127.18 pg/mL, (p-Value = 0.007). ANGPTL7 expression in adipose tissue was also reduced after exercise. Finally, ANGPTL7 circulating level showed significant association with TG level in the obese subjects (R2 = 0.183, p-Value = 0.03). Conclusion In conclusion, our data shows for the first time that obesity increases the level of ANGPTL7 in both plasma and adipose tissue. Increased expression of ANGPTL7 might play a minor role in the regulation of TG level in obese subjects either directly or through interaction with other ANGPTL protein members. Physical exercise reduced the level of ANGPTL7 highlighting the potential for targeting this protein as a therapeutic target for regulating dyslipidemia.