Experimental and theoretical analyses and investigation of intermolecular interactions and antibacterial activity of a novel proton transfer compound:8-hydroxyquinolinium oxalate monohydrate.

A novel proton transfer compound, 8-hydroxyquinolinium oxalate monohydrate was synthesised by solid state grinding of 8-hydroxyquinoline and oxalic acid. The resulting compound is characterised by single crystal X-ray diffraction (SXRD), FT-IR, UV-Visible, TG/DTG, DTA and DSC analyses. The compound crystallizes in monoclinic crystal system with space group P21/n. The carboxylate oxygen O2 which acts as a tetrafurcated acceptor of four hydrogen bonds is the main feature of the crystal structure. The molecules are linked together by O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds. Carbonyl-carbonyl interactions play a crucial role in stabilising the crystal packing. Hirshfeld surface analysis and the associated finger print plots facilitates the comparison of intermolecular interactions. The nature of charge density distribution and topological parameters of the proton transfer region N1-H1A⋯O2 hydrogen bond reveals that the bond has considerable covalent character. Natural Bond Orbital (NBO) has been extended to analyse the nature and strength of intermolecular interactions. Topology analysis using ELF and LOL reveals electron localisation and depletion regions. ADMET analysis reveals that the compound satisfies Lipinski's rule of five and drug likeness. Antibacterial activity was screened against 3 g positive - Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus and 2 g negative strains- Klebsiella pneumonia and Salmonella typhi by employing disc diffusion method.

Exploring the presence and distribution of microplastics in subterranean estuaries from southwest India.

Rivers, surface runoff, and the wind all transport microplastics (MPs) to the ocean. There is a knowledge gap concerning the distribution of microplastics in transitional subterranean estuaries. Here, we report the presence of microplastics in the pore water, groundwater, and sea water from four locations in southwest India. Pore water, groundwater, and seawater had mean MP abundances (± standard deviations) of 0.75 (±0.66), 0.15 (±0.1), and 0.11 (±0.07) MPs/l, respectively. Fibres were the dominant category of MPs found. Fourier-transformed infrared spectroscopy revealed the presence of polymers like polyester, low-density polyethylene, and polystyrene. Possible sources of microplastic are fishing activities, tourism, and coastal residents. The microplastics-derived risk assessment scores indicate severe risk to the ecosystems. Fibrous microplastics in pore water indicate that these linear particles can migrate vertically through sandy sediments, reaching subterranean estuaries. We believe submarine groundwater discharge can act as a possible pathway for microplastics to enter the oceans.

A review of Indian species of Phrynocaria Timberlake (Coleoptera, Coccinellidae) with notes on synonymy and a new species from South India, hitherto misidentified as Coelophora circumusta (Mulsant).

Indian species of Phrynocaria Timberlake, 1943 (Coleoptera: Coccinellidae) are briefly reviewed and illustrated with notes on diagnosis, nomenclature, distribution and hosts. Coelophora circumusta (Mulsant, 1850), which has a limited distribution in India, is transferred to Phrynocaria (new combination) and Coelophora moseri Weise, 1902 is synonymized with it (new synonym). A new species, Phrynocaria perfida Poorani, sp. n. (Coleoptera, Coccinellidae) is described from South India based on specimens hitherto misidentified as a variety of C. circumusta. The validity of Phrynocaria funebris (Crotch, 1874) is confirmed based on examination and dissection of the type specimen; the species is redescribed and the male genitalia illustrated.

Insulin resistance in 3T3-L1 adipocytes by TNF-α is improved by punicic acid through upregulation of insulin signalling pathway and endocrine function, and downregulation of proinflammatory cytokines.

Insulin resistance (IR) has become a major threat to public health due to its role in metabolic syndrome. Inflammation associated with IR is an interesting area of biomedical research in recent years and is expected to affect insulin signalling pathway via downregulating glucose transporters. In the present study, we evaluate the potential of punicic acid (PA), a nutraceutical found in pomegranate seed oil, against TNF-α induced alteration in 3T3-L1 adipocytes on glucose metabolism, endocrine function and inflammation. IR was induced in 3T3-L1 adipocytes by treating with TNF-α (10 ng/mL) and various concentrations of PA (5, 10, 30 µM) were incubated simultaneously. After 24 h, we found that TNF-α treatment increased mRNA expression of SOCS3, PTP1B and a decrease in IRS1 causing diminished glucose uptake. Further, it showed significantly increased transcriptional activity of NFκB and leptin secretion while PA maintained leptin levels normal. Additionally, PA prevented the over-expression of phosphorylated JNK in a dose dependent manner during IR. PA also ameliorated significantly the upregulation of proinflammatory cytokines. From the results, we conclude that PA is effective to ameliorate TNF-α induced IR and also we recommend the intake of PA for control and management of IR and its associated complications.

Development of insulin resistance through sprouting of inflammatory markers during hypoxia in 3T3-L1 adipocytes and amelioration with curcumin.

The role of phytochemicals in general well-being has been recognized. Curcumin is an ideal example. Hypoxia in adipose tissue is a major cause of inflammation and insulin resistance in obesity. Herein we mainly explored inflammation, insulin resistance and angiogenesis in 3T3-L1 adipocytes and possible reversal with the curcumin during hypoxia. Hypoxia for 24h significantly increased (P ≤ 0.05) the secretion of monocyte chemotactic protein-1 (4.59 fold), leptin (2.96 fold) and reduced adiponectin (2.93 fold). mRNA level of resistin (6.8 fold) and toll-like receptor-4 (TLR-4) (8.8 fold) was upregulated. Increased serine phosphorylation of insulin receptor substrate 1 (IRS-1) (1.9 fold) and decreased expression of insulin receptor substrate 2 (IRS-2) (0.53 fold) in hypoxic group were observed. Hypoxia significantly increased (P ≤ 0.05) basal glucose uptake (3.3 fold), GLUT-1 expression and angiogenic factors but down regulated GLUT-4. Curcumin protected adipocytes from hypoxia induced inflammation and insulin resistance via reducing inflammatory adipokine, nuclear factor-κB (NF-κB)/c-jun N-terminal kinase (JNK) and serine phosphorylation of IRS-1 receptors and improving adiponectin secretion.

Insulin resistance by TNF-α is associated with mitochondrial dysfunction in 3T3-L1 adipocytes and is ameliorated by punicic acid, a PPARγ agonist.

Punicic acid (PA), a poly unsaturated fatty acid found abundantly in pomegranate seed oil is reported to have PPARγ agonist property. TNF-α mediated insulin resistance plays an important role in the pathogenesis of diabetes and is associated with severe mitochondrial impairment. In this study, PA was evaluated for its ability to ameliorate TNF-α induced mitochondrial dysfunctions in 3T3-L1 adipocytes. For this, we examined the alterations in mitochondrial energetics, biogenesis, transmembrane potential and dynamics in TNF-α induced insulin resistant model of 3T3-L1 adipocytes. PA improved glucose uptake, ROS accumulation, mitochondrial biogenesis and energetics in TNF-α treated cells. In addition, treatment with PA was found to ameliorate TNF-α induced alterations in proteins associated with mitochondrial dynamics like FIS1 and OPA1. These findings suggest that PA can be considered as an active lead for the management of insulin resistance and associated mitochondrial dysfunctions.

(-)-Hydroxycitric acid attenuates endoplasmic reticulum stress-mediated alterations in 3T3-L1 adipocytes by protecting mitochondria and downregulating inflammatory markers.

Endoplasmic reticulum (ER) stress is an emerging potential therapeutic target for metabolic syndrome due to its role in synthesis, secretion, and folding of proteins. It leads to an increased production of reactive oxygen species (ROS) which, along with mitochondrial dysfunction and reduced antioxidant defense, causes chronic cell injury. The present investigation aims to observe the alterations in adipocytes due to ER stress and the protective effect of hydroxycitric acid (HCA), a bioactive from Garcinia species, to develop the same as a nutraceutical. ER stress was induced in mature 3T3-L1 adipocytes by treating them with tunicamycin (2µg/ml) for 18 h. Alterations in cell viability, innate antioxidant system (superoxide dismutase, glutathione peroxidase, and glutathione reductase), mitochondria (membrane potential, biogenesis, and transition pore opening), and inflammatory cytokines (tumor necrosis factor, monocyte chemoattractant protein, interferon-γ, interleukin (IL)-10, IL-6, and IL-1ß) during ER stress, and co-treatment with HCA were analyzed. Endocrine function of adipocytes was also assessed by measuring adiponectin and leptin secretion levels. HCA protected the cells from ER stress by improving the antioxidant status and mitochondrial functions. The results validate nutraceutical properties of the edible bioactive, commonly used for culinary purpose. A more detailed study on the mechanism of action of HCA is required for developing it as a therapeutic agent for metabolic syndrome.

An in vitro study reveals the nutraceutical potential of punicic acid relevant to diabetes via enhanced GLUT4 expression and adiponectin secretion.

The prevalence of diabetes and heart diseases is increasing in the world. Nutraceuticals of natural origin are gaining importance as an alternative to modern drugs for the management of metabolic syndrome. In the present study, punicic acid (PA), a major bioactive found in pomegranate seed, was subjected for biological characterization with respect to peroxisome proliferator-activated receptor gamma (PPARγ) agonist property in an in vitro system (3T3-L1 adipocytes). We evaluated the adipogenic potential of various concentrations (5, 10 and 30 µM) of PA by studying triglyceride accumulation and glycerol-3-phosphate dehydrogenase (GPDH) activity in adipocytes, which were found to be increased moderately compared with the positive control, i.e. rosiglitazone (RG). Glucose uptake activity (↑225.93% ± 2.55% for 30 µM of PA), and the prevention of reactive oxygen species (ROS) generation (↓57 ± 1.83% for 30 µM of PA) in adipocytes with PA were also evaluated. We also found that PA increased adiponectin secretion and upregulated GLUT4 expression and translocation in adipocytes. Molecular modelling studies revealed a high binding affinity of PA to the PPARγ ligand binding domain. An in vitro ligand binding assay based on time-resolved fluorescence resonance energy transfer (TR-FRET) also proved PA as a PPARγ agonist. Finally, we conclude that PA is a potential nutraceutical and should be encouraged for use both as a prophylactic and therapeutic agent.

Apigenin and quercetin ameliorate mitochondrial alterations by tunicamycin-induced ER stress in 3T3-L1 adipocytes.

Endoplasmic reticulum (ER) is an important organelle with functions like protein synthesis, folding, and calcium homeostasis. ER stress, a condition that dramatically affects protein folding homeostasis in cells, has been associated with a number of metabolic disorders. Emerging clinical and preclinical evidence support the notion that pharmacological modulators of ER stress have therapeutic potential as a novel target for treating metabolic diseases. ER is in physical contact with mitochondria, and there is a strong cross talk between these organelles at functional level. The present investigation was aimed to check the mitochondrial alterations in adipocytes with tunicamycin-induced ER stress and modulation by apigenin and quercetin. For this, differentiated adipocytes were incubated with tunicamycin (2 µg/ml) for 18 h, and changes in mitochondrial membrane potential, biogenesis, reactive oxygen species production, and adiponectin secretion were seen. Tunicamycin-induced ER stress altered reactive oxygen species (ROS) (6.34-fold↑), membrane potential (4.1-fold↑), mitochondrial biogenesis (2.4-fold↓), and adiponectin secretion (3.5-fold↓). Apigenin and quercetin ameliorated alterations in mitochondria. From results, we conclude that ER stress significantly alters mitochondrial functions and both the bioactives significantly protected mitochondrial alterations during ER stressand reestablished adiponectin secretion.

Bilobalide attenuates hypoxia induced oxidative stress, inflammation, and mitochondrial dysfunctions in 3T3-L1 adipocytes via its antioxidant potential.

Excessive expansion of white adipose tissue leads to hypoxia which is considered as a key factor responsible for adipose tissue dysfunction in obesity. Hypoxia induces inflammation, insulin resistance, and other obesity related complications. So the hypoxia-signalling pathway is expected to provide a new target for the treatment of obesity-associated complications. Inhibition or downregulation of the HIF-1 pathway could be an effective target for the treatment of obesity related hypoxia. In the present study, we evaluated the effect of hypoxia on functions of 3T3-L1 adipocytes emphasising on oxidative stress, antioxidant status, inflammation and mitochondrial functions. We have also evaluated the protective role of bilobalide, a bioactive from Gingko biloba, on hypoxia induced alterations. The results revealed that hypoxia significantly altered all the vital parameters of adipocyte biology like HIF-1α expression (103.47% ↑), lactate and glycerol release (184.34% and 69.1% ↑, respectively), reactive oxygen species (ROS) production (432.53% ↑), lipid and protein oxidation (376.6% and 566.6% ↑, respectively), reduction in antioxidant enzymes (superoxide dismutase and catalase) status, secretion of inflammatory markers (TNF-α, IL-6, IL-1ß and IFN-γ) and mitochondrial functions (mitochondrial mass, membrane potential, permeability transition pore integrity, superoxide generation). Bilobalide significantly protected adipocytes from adverse effects of hypoxia in a dose-dependent manner by attenuating oxidative stress, inflammation and protecting mitochondria. Acriflavine (HIF-1 inhibitor) was used as positive control. On the basis of this study, a detailed investigation is needed to delineate the mechanism of action of bilobalide to develop it as therapeutic target for obesity.