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1.
Curr Biol ; 34(15): 3537-3549.e5, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39047734

ABSTRACT

Decoding human speech requires the brain to segment the incoming acoustic signal into meaningful linguistic units, ranging from syllables and words to phrases. Integrating these linguistic constituents into a coherent percept sets the root of compositional meaning and hence understanding. One important cue for segmentation in natural speech is prosodic cues, such as pauses, but their interplay with higher-level linguistic processing is still unknown. Here, we dissociate the neural tracking of prosodic pauses from the segmentation of multi-word chunks using magnetoencephalography (MEG). We find that manipulating the regularity of pauses disrupts slow speech-brain tracking bilaterally in auditory areas (below 2 Hz) and in turn increases left-lateralized coherence of higher-frequency auditory activity at speech onsets (around 25-45 Hz). Critically, we also find that multi-word chunks-defined as short, coherent bundles of inter-word dependencies-are processed through the rhythmic fluctuations of low-frequency activity (below 2 Hz) bilaterally and independently of prosodic cues. Importantly, low-frequency alignment at chunk onsets increases the accuracy of an encoding model in bilateral auditory and frontal areas while controlling for the effect of acoustics. Our findings provide novel insights into the neural basis of speech perception, demonstrating that both acoustic features (prosodic cues) and abstract linguistic processing at the multi-word timescale are underpinned independently by low-frequency electrophysiological brain activity in the delta frequency range.


Subject(s)
Comprehension , Magnetoencephalography , Speech Perception , Humans , Speech Perception/physiology , Comprehension/physiology , Male , Female , Adult , Young Adult , Speech/physiology , Delta Rhythm/physiology , Brain/physiology , Linguistics
2.
PLoS One ; 19(6): e0305333, 2024.
Article in English | MEDLINE | ID: mdl-38889141

ABSTRACT

Language is rooted in our ability to compose: We link words together, fusing their meanings. Links are not limited to neighboring words but often span intervening words. The ability to process these non-adjacent dependencies (NADs) conflicts with the brain's sampling of speech: We consume speech in chunks that are limited in time, containing only a limited number of words. It is unknown how we link words together that belong to separate chunks. Here, we report that we cannot-at least not so well. In our electroencephalography (EEG) study, 37 human listeners learned chunks and dependencies from an artificial grammar (AG) composed of syllables. Multi-syllable chunks to be learned were equal-sized, allowing us to employ a frequency-tagging approach. On top of chunks, syllable streams contained NADs that were either confined to a single chunk or crossed a chunk boundary. Frequency analyses of the EEG revealed a spectral peak at the chunk rate, showing that participants learned the chunks. NADs that cross boundaries were associated with smaller electrophysiological responses than within-chunk NADs. This shows that NADs are processed readily when they are confined to the same chunk, but not as well when crossing a chunk boundary. Our findings help to reconcile the classical notion that language is processed incrementally with recent evidence for discrete perceptual sampling of speech. This has implications for language acquisition and processing as well as for the general view of syntax in human language.


Subject(s)
Electroencephalography , Language , Humans , Female , Male , Adult , Young Adult , Speech Perception/physiology , Speech/physiology , Learning/physiology , Brain/physiology
3.
Environ Toxicol ; 39(8): 4120-4133, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38654489

ABSTRACT

Lipotoxicity leads to numerous metabolic disorders such as nonalcoholic steatohepatitis. Luteolin, apigenin, and chrysin are three flavones with known antioxidant and anti-inflammatory properties, but whether they inhibit lipotoxicity-mediated NLRP3 inflammasome activation was unclear. To address this question, we used J774A.1 macrophages and Kupffer cells stimulated with 100 µM palmitate (PA) in the presence or absence of 20 µM of each flavone. PA increased p-PERK, p-IRE1α, p-JNK1/2, CHOP, and TXNIP as well as p62 and LC3-II expression and induced autophagic flux damage. Caspase-1 activation and IL-1ß release were also noted after 24 h of exposure to PA. In the presence of the PERK inhibitor GSK2656157, PA-induced CHOP and TXNIP expression and caspase-1 activation were mitigated. Compared with PA treatment alone, Bcl-2 coupled to beclin-1 was elevated and autophagy was reversed by the JNK inhibitor SP600125. With luteolin, apigenin, and chrysin treatment, PA-induced ROS production, ER stress, TXNIP expression, autophagic flux damage, and apoptosis were ameliorated. Moreover, TXNIP binding to NLRP3 and IL-1ß release in response to LPS/PA challenge were reduced. These results suggest that luteolin, apigenin, and chrysin protect hepatic macrophages against PA-induced NLRP3 inflammasome activation and autophagy damage by attenuating endoplasmic reticulum stress.


Subject(s)
Apigenin , Autophagy , Endoplasmic Reticulum Stress , Flavonoids , Inflammasomes , Luteolin , Macrophages , NLR Family, Pyrin Domain-Containing 3 Protein , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Flavonoids/pharmacology , Endoplasmic Reticulum Stress/drug effects , Apigenin/pharmacology , Animals , Luteolin/pharmacology , Autophagy/drug effects , Inflammasomes/drug effects , Inflammasomes/metabolism , Mice , Macrophages/drug effects , Cell Line
4.
Nutr Res ; 121: 95-107, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38056034

ABSTRACT

Tumor necrosis factor α (TNFα), an inflammatory cytokine, induces lipolysis and increases circulating concentrations of free fatty acids. In addition, TNFα is the first adipokine produced by adipose tissue in obesity, contributing to obesity-associated metabolic disease. Given that benzyl isothiocyanate (BITC) is a well-known anti-inflammatory agent, we hypothesized that BITC can ameliorate TNFα-induced lipolysis and investigated the working mechanisms involved. We first challenged 3T3-L1 adipocytes with TNFα to induce lipolysis, which was confirmed by increased glycerol release, decreased protein expression of peroxisome proliferator-activated receptor γ (PPARγ) and perilipin 1 (PLIN1), and increased phosphorylation of ERK, protein kinase A (PKA), and hormone-sensitive lipase (HSL). However, inhibition of ERK or PKA significantly attenuated the lipolytic activity of TNFα. Meanwhile, pretreatment with BITC significantly ameliorated the lipolytic activity of TNFα; the TNFα-induced phosphorylation of ERK, PKA, and HSL; the TNFα-induced ubiquitination of PPARγ; the TNFα-induced decrease in PPARγ nuclear protein binding to PPAR response element; and the TNFα-induced decrease in PLIN1 protein expression. Our results indicate that BITC ameliorates TNFα-induced lipolysis by inhibiting the ERK/PKA/HSL signaling pathway, preventing PPARγ proteasomal degradation, and maintaining PLIN1 protein expression.


Subject(s)
Sterol Esterase , Tumor Necrosis Factor-alpha , Animals , Mice , Tumor Necrosis Factor-alpha/pharmacology , Tumor Necrosis Factor-alpha/metabolism , Sterol Esterase/metabolism , Lipolysis , 3T3-L1 Cells , PPAR gamma/metabolism , Signal Transduction , Phosphorylation , Adipocytes/metabolism , Obesity/metabolism , Perilipin-1/metabolism
5.
Am J Chin Med ; 51(8): 2175-2193, 2023.
Article in English | MEDLINE | ID: mdl-37930331

ABSTRACT

Andrographolide (AND) is a bioactive component of the herb Andrographis paniculata and a well-known anti-inflammatory agent. Atherosclerosis is a chronic inflammatory disease of the vasculature, and oxidized LDL (oxLDL) is thought to contribute heavily to atherosclerosis-associated inflammation. The aim of this study was to investigate whether AND mitigates oxLDL-mediated foam cell formation and diet-induced atherosclerosis (in mice fed a high-fat, high-cholesterol, high-cholic acid [HFCCD] diet) and the underlying mechanisms involved. AND attenuated LPS/oxLDL-mediated foam cell formation, IL-1[Formula: see text] mRNA and protein (p37) expression, NLR family pyrin domain containing 3 (NLRP3) mRNA and protein expression, caspase-1 (p20) protein expression, and IL-1[Formula: see text] release in BMDMs. Treatment with oxLDL significantly induced protein and mRNA expression of CD36, lectin-like oxLDL receptor-1 (LOX-1), and scavenger receptor type A (SR-A), whereas pretreatment with AND significantly inhibited protein and mRNA expression of SR-A only. Treatment with oxLDL significantly induced ROS generation and Dil-oxLDL uptake; however, pretreatment with AND alleviated oxLDL-induced ROS generation and Dil-oxLDL uptake. HFCCD feeding significantly increased aortic lipid accumulation, ICAM-1 expression, and IL-1[Formula: see text] mRNA expression, as well as blood levels of glutamic pyruvic transaminase (GPT), total cholesterol, and LDL-C. AND co-administration mitigated aortic lipid accumulation, the protein expression of ICAM-1, mRNA expression of IL-1[Formula: see text] and ICAM-1, and blood levels of GPT. These results suggest that the working mechanisms by which AND mitigates atherosclerosis involve the inhibition of foam cell formation and NLRP3 inflammasome-dependent vascular inflammation as evidenced by decreased SR-A expression and IL-1[Formula: see text] release, respectively.


Subject(s)
Atherosclerosis , Inflammasomes , Animals , Mice , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Intercellular Adhesion Molecule-1/metabolism , Reactive Oxygen Species/metabolism , Macrophages/metabolism , Lipoproteins, LDL , Foam Cells/metabolism , Receptors, Scavenger , Inflammation/metabolism , Cholesterol/metabolism , Atherosclerosis/drug therapy , Atherosclerosis/etiology , Atherosclerosis/metabolism , RNA, Messenger/metabolism , Interleukin-1/metabolism
6.
Sci Rep ; 13(1): 18522, 2023 10 28.
Article in English | MEDLINE | ID: mdl-37898645

ABSTRACT

Memory is fleeting. To avoid information loss, humans need to recode verbal stimuli into chunks of limited duration, each containing multiple words. Chunk duration may also be limited neurally by the wavelength of periodic brain activity, so-called neural oscillations. While both cognitive and neural constraints predict some degree of behavioral regularity in processing, this remains to be shown. Our analysis of self-paced reading data from 181 participants reveals periodic patterns at a frequency of [Formula: see text] 2 Hz. We defined multi-word chunks by using a computational formalization based on dependency annotations and part-of-speech tags. Potential chunk outputs were first generated from the computational formalization and the final chunk outputs were selected based on normalized pointwise mutual information. We show that behavioral periodicity is time-aligned to multi-word chunks, suggesting that the multi-word chunks generated from local dependency clusters may minimize memory demands. This is the first evidence that sentence processing behavior is periodic, consistent with a role of both memory constraints and endogenous electrophysiological rhythms in the formation of chunks during language comprehension.


Subject(s)
Language , Memory , Humans , Periodicity
8.
Toxicol Appl Pharmacol ; 462: 116424, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36775252

ABSTRACT

The NLRP3 inflammasome plays an important role in the pathogenesis of numerous inflammation-related diseases. Benzyl isothiocyanate (BITC) is rich in cruciferous vegetables and possesses potent antioxidant, anti-inflammatory, anti-cancer, and anti-obesogenic properties. In this study, we investigated the role of the NLRP3 inflammasome in the protection by BITC against steatohepatitis and insulin resistance. A mouse model of high-fat/cholesterol/cholic acid diet (HFCCD)-induced steatohepatitis, LPS/nigericin-stimulated primary Kupffer cells, and IL-1ß treated primary hepatocytes were used. BITC attenuated LPS/nigericin-induced activation of the NLRP3 inflammasome by enhancing protein kinase A-dependent NLRP3 ubiquitination, which increased the degradation of NLRP3 and reduced IL-1ß secretion in Kupffer cells. In hepatocytes, BITC pretreatment reversed the IL-1ß-induced decrease in the phosphorylation of IR, AKT, and GSK3ß in response to insulin. After 12 weeks of HFCCD feeding, increases in blood alanine aminotransferase (ALT) and glucose levels were ameliorated by BITC. Hepatic IL-1ß production, macrophage infiltration, and collagen expression induced by HFCCD were also mitigated by BITC. BITC suppresses activation of the NLRP3 inflammasome in Kupffer cells by enhancing the PKA-dependent ubiquitination of NLRP3, which leads to suppression of IL-1ß production and subsequently ameliorates hepatic inflammation and insulin resistance.


Subject(s)
Insulin Resistance , Non-alcoholic Fatty Liver Disease , Mice , Animals , Inflammasomes/metabolism , Kupffer Cells , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Nigericin/metabolism , Lipopolysaccharides/pharmacology , Non-alcoholic Fatty Liver Disease/metabolism , Cholesterol/metabolism , Diet, High-Fat , Inflammation/metabolism , Interleukin-1beta/metabolism , Mice, Inbred C57BL
9.
Am J Chin Med ; 51(1): 129-147, 2023.
Article in English | MEDLINE | ID: mdl-36419253

ABSTRACT

Andrographolide is the major bioactive component of the herb Andrographis paniculata and is a potent anti-inflammatory agent. Obesity leads to an excess of free fatty acids, particularly palmitic acid (PA), in the circulation. Obesity also causes the deposition of ectopic fat in nonadipose tissues, which leads to lipotoxicity, a condition closely associated with inflammation. Here, we investigated whether andrographolide could inhibit PA-induced inflammation by activating autophagy, activating the antioxidant defense system, and blocking the activation of the NLRP3 inflammasome. Bone marrow-derived macrophages (BMDMs) were primed with lipopolysaccharide (LPS) and then activated with PA. LPS/PA treatment increased both the mRNA expression of NLRP3 and IL-1[Formula: see text] and the release of IL-1[Formula: see text] in BMDMs. Andrographolide inhibited the LPS/PA-induced protein expression of caspase-1 and the release of IL-1[Formula: see text]. Furthermore, andrographolide attenuated LPS/PA-induced mtROS generation by first promoting autophagic flux and catalase activity, and ultimately inhibiting activation of the NLRP3 inflammasome. Our results suggest that the mechanisms by which andrographolide downregulates LPS/PA-induced IL-1[Formula: see text] release in BMDMs involve promoting autophagic flux and catalase activity. Andrographolide may thus be a candidate to prevent obesity- and lipotoxicity-driven chronic inflammatory disease.


Subject(s)
Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Animals , Mice , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Lipopolysaccharides/adverse effects , Catalase/metabolism , Macrophages/metabolism , Inflammation/metabolism , Antioxidants/metabolism , Interleukin-1/metabolism , Mice, Inbred C57BL
10.
Food Chem Toxicol ; 171: 113554, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36509263

ABSTRACT

Abnormal accumulation of lipids in liver leads to uncontrolled endoplasmic reticulum (ER) stress and autophagy. Luteolin is known to have antioxidant, anti-inflammatory, and anti-cancer properties, but whether it protects against lipotoxicity in liver remains unclear. In this study, we challenged AML12 liver cells and mouse primary hepatocytes with palmitic acid (PA) with or without luteolin pretreatment. In the presence of PA, reactive oxygen species (ROS) production was increased at 3 h, followed by enhancement of expression of p-PERK, ATF4, p-eIF2α, CHOP, and TXNIP (ER stress markers) and p-p62 and LC3II/LC3I ratio (autophagy markers), in both primary hepatocytes and AML12 cells. When PA treatment was extended up to 24 h, apoptosis was induced as evidenced by an increase in caspase-3 activation. RFP-GFP-LC3B transfection further revealed that the fusion of autophagosomes with lysosomes was damaged by PA. With luteolin treatment, the expression of antioxidant enzymes, i.e., heme oxygenase-1 and glutathione peroxidase, was upregulated, and PA-induced ROS production, ER stress, and cell death were dose-dependently ameliorated. Luteolin could also reverse the damage caused to autophagic flux. These results indicate that luteolin protects hepatocytes against PA assault by enhancing antioxidant defense, which can attenuate ER stress and autophagy as well as promote autophagic flux.


Subject(s)
Luteolin , Palmitates , Mice , Animals , Luteolin/metabolism , Antioxidants/pharmacology , Reactive Oxygen Species/metabolism , Hepatocytes/metabolism , Endoplasmic Reticulum Stress , Palmitic Acid/pharmacology , Autophagy , Apoptosis
11.
Neurobiol Lang (Camb) ; 3(4): 538-555, 2022.
Article in English | MEDLINE | ID: mdl-37215342

ABSTRACT

Neural responses appear to synchronize with sentence structure. However, researchers have debated whether this response in the delta band (0.5-3 Hz) really reflects hierarchical information or simply lexical regularities. Computational simulations in which sentences are represented simply as sequences of high-dimensional numeric vectors that encode lexical information seem to give rise to power spectra similar to those observed for sentence synchronization, suggesting that sentence-level cortical tracking findings may reflect sequential lexical or part-of-speech information, and not necessarily hierarchical syntactic information. Using electroencephalography (EEG) data and the frequency-tagging paradigm, we develop a novel experimental condition to tease apart the predictions of the lexical and the hierarchical accounts of the attested low-frequency synchronization. Under a lexical model, synchronization should be observed even when words are reversed within their phrases (e.g., "sheep white grass eat" instead of "white sheep eat grass"), because the same lexical items are preserved at the same regular intervals. Critically, such stimuli are not syntactically well-formed; thus a hierarchical model does not predict synchronization of phrase- and sentence-level structure in the reversed phrase condition. Computational simulations confirm these diverging predictions. EEG data from N = 31 native speakers of Mandarin show robust delta synchronization to syntactically well-formed isochronous speech. Importantly, no such pattern is observed for reversed phrases, consistent with the hierarchical, but not the lexical, accounts.

12.
Am J Chin Med ; 49(6): 1473-1491, 2021.
Article in English | MEDLINE | ID: mdl-34240660

ABSTRACT

14-Deoxy-11,12-didehydroandrographolide (deAND), a bioactive component of Andrographis paniculata, has antidiabetic activity. AMP-activated protein kinase (AMPK) regulates glucose transport and ameliorates insulin resistance. The aim of the present study was to investigate whether activation of AMPK is involved in the mechanism by which deAND ameliorates insulin resistance in muscles. deAND amounts up to 40 [Formula: see text]M dose-dependently activated phosphorylation of AMPK[Formula: see text] and TBC1D1 in C2C12 myotubes. In addition, deAND significantly activated phosphorylation of LKB1 at 6 h after treatment, and this activation was maintained up to 48 h. deAND increased glucose uptake at 18 h after treatment, and this increase was time dependent up to 72 h. Compound C, an inhibitor of AMPK, suppressed deAND-induced phosphorylation of AMPK[Formula: see text] and TBC1D1 and reversed the effect on glucose uptake. In addition, the expression of GLUT4 mRNA and protein in C2C12 myotubes was up-regulated by deAND in a time-dependent manner. Promotion of GLUT4 gene transcription was verified by a pGL3-GLUT4 (837 bp) reporter assay. deAND also increased the nuclear translocation of MEF-2A and PPAR[Formula: see text]. After 16 weeks of feeding, the high-fat diet (HFD) inhibited phosphorylation of AMPK[Formula: see text] and TBC1D1 in skeletal muscle of obese C57BL/6JNarl mice, and deactivation of AMPK[Formula: see text] and TBC1D1 by the HFD was abolished by deAND supplementation. Supplementation with deAND significantly promoted membrane translocation of GLUT4 compared with the HFD group. Supplementation also significantly increased GLUT4 mRNA and protein expression in skeletal muscle compared with the HFD group. The hypoglycemic effects of deAND are likely associated with activation of the LKB1/AMPK[Formula: see text]/TBC1D1/GLUT4 signaling pathway and stimulation of MEF-2A- and PPAR[Formula: see text]-dependent GLUT4 gene expression, which account for the glucose uptake into skeletal muscle and lower blood glucose levels.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Diterpenes/pharmacology , GTPase-Activating Proteins/metabolism , Glucose Intolerance/drug therapy , Glucose Transporter Type 4/drug effects , Muscle Fibers, Skeletal/drug effects , Protein Serine-Threonine Kinases/metabolism , Animals , Disease Models, Animal , Male , Mice , Mice, Inbred C57BL , Mice, Obese
13.
Front Hum Neurosci ; 15: 591613, 2021.
Article in English | MEDLINE | ID: mdl-33613208

ABSTRACT

Event-related potential components are sensitive to the processes underlying how questions are understood. We use so-called "covert" wh-questions in Mandarin to probe how such components generalize across different kinds of constructions. This study shows that covert Mandarin wh-questions do not elicit anterior negativities associated with memory maintenance, even when such a dependency is unambiguously cued. N = 37 native speakers of Mandarin Chinese read Chinese questions and declarative sentences word-by-word during EEG recording. In contrast to prior studies, no sustained anterior negativity (SAN) was observed between the cue word, such as the question-embedding verb "wonder," and the in-situ wh-filler. SANs have been linked with working memory maintenance, suggesting that grammatical features may not impose the same maintenance demands as the content words used in prior work.

14.
Toxicol Appl Pharmacol ; 410: 115341, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33242555

ABSTRACT

Andrographolide (AND) is the major diterpenoid in A. paniculata with wide clinical application and has been shown to be a potent anti-inflammatory agent. Gout is the leading inflammatory disease of the joints, and the deposition of urate in the articular cavity attracts immune cells that release inflammatory cytokines. Monosodium urate (MSU) is known to be one of the activators of the NLRP3 (NLR family pyrin domain containing 3) inflammasome. After activation, the NLRP3 inflammasome releases interleukin-1ß (IL-1ß), which causes the development of many inflammatory diseases. The aim of the present study was to investigate whether AND attenuates the release of IL-1ß mediated by the NLRP3 inflammasome. The effects of AND were studied in bone marrow-derived macrophages (BMDMs) treated with lipopolysaccharide (LPS) and MSU and in mice with MSU-induced joint inflammation. AND suppressed MSU phagocytosis dose-dependently and markedly inhibited LPS- and MSU-induced IL-1ß release in BMDMs. Moreover, AND pretreatment inhibited the LPS-induced NLRP3 inflammasome priming stage by inhibiting the IKK/NFκB signaling pathway, which resulted in decreased protein expression of NLRP3 and proIL-1ß. AND induced HO-1 protein expression in a dose-dependent manner and attenuated MSU-induced ROS generation. Silencing HO-1 mitigated AND inhibition of LPS/MSU-induced IL-1ß release in J774A.1 cells. In addition, AND decreased MSU-mediated ASC binding to NLRP3. Oral administration of AND attenuated MSU-induced monocyte infiltration in mouse knee joints. These results suggest that the working mechanisms by which AND down-regulates MSU-induced joint inflammation might be via HO-1 induction and attenuation of ROS-mediated NLRP3 inflammasome assembly and subsequent IL-1ß release.


Subject(s)
Diterpenes/pharmacology , Interleukin-1beta/antagonists & inhibitors , Knee Joint/drug effects , Macrophages/drug effects , Monocytes/drug effects , Uric Acid/toxicity , Animals , Anti-Inflammatory Agents/pharmacology , Antioxidants/toxicity , Cell Line , Cells, Cultured , Humans , Interleukin-1beta/metabolism , Knee Joint/metabolism , Knee Joint/pathology , Macrophages/metabolism , Male , Mice , Mice, Inbred C57BL , Monocytes/metabolism
15.
Toxicol Appl Pharmacol ; 393: 114941, 2020 04 15.
Article in English | MEDLINE | ID: mdl-32126212

ABSTRACT

Incidence of nonalcoholic fatty liver disease is increasing worldwide. Activation of the NLRP3 inflammasome is central to the development of diet-induced nonalcoholic steatohepatitis (NASH). We investigated whether benzyl isothiocyanate (BITC) ameliorates diet-induced NASH and the mechanisms involved. C57BL/6 J mice fed a high-fat diet containing cholesterol and cholic acid (HFCCD) and Kupffer cells stimulated with LPS and cholesterol crystals (CC) were studied. LPS/CC increased the expression of the active form of caspase 1 (p20) and the secretion of IL-1ß by Kupffer cells, and these changes were reversed by MCC950, an NLRP3 inflammasome inhibitor. LPS/CC-induced NLRP3 inflammasome activation and IL-1ß production were dose-dependently attenuated by BITC. BITC decreased cathepsin B release from lysosomes and binding to NLRP3 induced by LPS/CC. Compared with a normal diet, the HFCCD increased serum levels of ALT, AST, total cholesterol, and IL-1ß and hepatic contents of triglycerides and total cholesterol. BITC administration (0.1% in diet) reversed the increase in AST and hepatic triglycerides in the HFCCD group. Moreover, BITC suppressed lipid accumulation, macrophage infiltration, fibrosis, crown-like structure formation, and p20 caspase 1 and p17 IL-1ß expression in liver in the HFCCD group. These results suggest that BITC ameliorates HFCCD-induced steatohepatitis by inhibiting the activation of NLRP3 inflammasome in Kupffer cells and may protect against diet-induced NASH.


Subject(s)
Cholesterol, Dietary/adverse effects , Cholesterol/chemistry , Cholic Acid/adverse effects , Diet, High-Fat/adverse effects , Inflammasomes/drug effects , Isothiocyanates/therapeutic use , Kupffer Cells/drug effects , NLR Family, Pyrin Domain-Containing 3 Protein/antagonists & inhibitors , Non-alcoholic Fatty Liver Disease/drug therapy , Animals , Cholesterol/blood , Dose-Response Relationship, Drug , Interleukin-1beta/metabolism , Lipid Metabolism/drug effects , Liver/metabolism , Liver Function Tests , Male , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/etiology , Triglycerides/metabolism
16.
J Agric Food Chem ; 67(25): 7136-7146, 2019 Jun 26.
Article in English | MEDLINE | ID: mdl-31240929

ABSTRACT

Benzyl isothiocyanate (BITC) and phenethyl isothiocyanate (PEITC) are organosulfur phytochemicals rich in cruciferous vegetables. We investigated the antiobesity and antihepatosteatosis activities of BITC and PEITC and the working mechanisms involved. C57BL/6J mice were fed a low-fat diet (LFD), a high-fat diet (HFD), or a HFD supplemented with 0.5 (L) or 1 g/kg (H) BITC or PEITC for 18 weeks. Compared with the HFD group, BITC or PEITC decreased the final body weight of mice in a dose-dependent manner [39.0 ± 3.1 (HFD), 34.4 ± 3.2 (BITC-L), 32.4 ± 2.8 (BITC-H), 36.2 ± 4.4 (PEITC-L), and 32.8 ± 2.9 (PEITC-H) g, p < 0.05], relative weight of epididymal fat [5.7 ± 0.4 (HFD), 4.7 ± 0.7 (BITC-L), 3.7 ± 0.3 (BITC-H), 4.4 ± 1.0 (PEITC-L), and 3.2 ± 0.6 (PEITC-H) %, p < 0.05], hepatic triglycerides [98.4 ± 6.0 (HFD), 81.0 ± 8.9 (BITC-L), 63.5 ± 5.6 (BITC-H), 69.3 ± 5.6 (PEITC-L), and 49.4 ± 2.9 (PEITC-H) mg/g, p < 0.05], and plasma total cholesterol [140 ± 21.3 (HFD), 109 ± 5.6 (BITC-L), 101 ± 11.3 (BITC-H), 126 ± 8.3 (PEITC-L), and 91.8 ± 12.7 (PEITC-H) mg/dL, p < 0.05]. Q-PCR and immunoblotting assays revealed that BITC and PEITC suppressed the expression of liver X receptor α, sterol regulatory element-binding protein 1c, stearoyl-CoA desaturase 1, fatty acid synthase, and acetyl-CoA carboxylase in both epididymal adipose and liver tissues. After a single oral administration of 85 mg/kg BITC or PEITC, the maximum plasma concentrations ( Cmax) of BITC and PEITC were 5.8 ± 2.0 µg/mL and 4.3 ± 1.9 µg/mL, respectively. In 3T3-L1 adipocytes, BITC and PEITC dose-dependently reduced adipocyte differentiation and cell cycle was arrested in G0/G1 phase. These findings indicate that BITC and PEITC ameliorate HFD-induced obesity and fatty liver by down-regulating adipocyte differentiation and the expression of lipogenic transcription factors and enzymes.


Subject(s)
Adipogenesis/drug effects , Fatty Liver/drug therapy , Isothiocyanates/administration & dosage , Obesity/drug therapy , Animals , Diet, High-Fat/adverse effects , Fatty Liver/metabolism , Fatty Liver/physiopathology , Humans , Male , Mice , Mice, Inbred C57BL , Obesity/metabolism , Obesity/physiopathology
17.
Mol Nutr Food Res ; 62(6): e1700616, 2018 03.
Article in English | MEDLINE | ID: mdl-29345776

ABSTRACT

SCOPE: The aim of this study is to investigate the signaling pathways by which allyl isothiocyanate (AITC) reduces adipocyte differentiation and the efficacy of AITC in suppressing galectin-12 levels as a therapeutic for high fat diet (HFD)-induced obesity. METHODS AND RESULTS: AITC presents anti-adipogenic effects on 3T3-L1 cells by decreasing lipid droplet accumulation in a dose-dependent manner. AITC suppresses 3T3-L1 differentiation into adipocytes by decreasing galectin-12 expression and by downregulating key adipogenic transcription factors. AITC influences the expression of 3T3-L1 pre-adipocytes by modulating adipokine expression (leptin and resistin) and by regulating the protein kinase B (PKB/Akt)/cAMP response element-binding protein (CREB) pathway. In HFD-fed mice, oral administration of AITC reduces the body weight, accumulation of lipid droplets in the liver, and white adipocyte size. CONCLUSION: In summary, the results indicate that AITC inhibits adipocyte differentiation by suppressing galectin-12 levels in 3T3L1 cells and has antiobesity effects in HFD-fed mice.


Subject(s)
Adipocytes/drug effects , Galectin 2/antagonists & inhibitors , Isothiocyanates/therapeutic use , Obesity/drug therapy , 3T3-L1 Cells , Adipocytes/cytology , Adipocytes/metabolism , Adipokines/genetics , Animals , Atherosclerosis/etiology , Cell Differentiation/drug effects , Cyclic AMP Response Element-Binding Protein/physiology , Isothiocyanates/pharmacology , Lipid Metabolism/drug effects , Male , Mice , Mice, Inbred C57BL
18.
Sci Rep ; 7: 41123, 2017 01 24.
Article in English | MEDLINE | ID: mdl-28117341

ABSTRACT

We have previously showed that IL-1ß is involved in the pathogenesis of both spontaneously occurring and passively induced IgA nephropathy (IgAN) models. However, the exact causal-relationship between NLRP3 inflammasome and the pathogenesis of IgAN remains unknown. In the present study, we showed that [1] IgA immune complexes (ICs) activated NLRP3 inflammasome in macrophages involving disruption of mitochondrial integrity and induction of mitochondrial ROS, bone marrow-derived dendritic cells (BMDCs) and renal intrinsic cells; [2] knockout of NLRP3 inhibited IgA ICs-mediated activation of BMDCs and T cells; and [3] knockout of NLRP3 or a kidney-targeting delivery of shRNA of NLRP3 improved renal function and renal injury in a mouse IgAN model. These results strongly suggest that NLRP3 inflammasome serves as a key player in the pathogenesis of IgAN partly through activation of T cells and mitochondrial ROS production and that a local, kidney-targeting suppression of NLRP3 be a therapeutic strategy for IgAN.


Subject(s)
Glomerulonephritis, IGA/metabolism , Inflammasomes/metabolism , Macrophages/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Animals , Female , Glomerulonephritis, IGA/immunology , Kidney/immunology , Kidney/metabolism , Mice , Mitochondria/metabolism , Reactive Oxygen Species/metabolism
19.
Ultrason Sonochem ; 36: 70-77, 2017 May.
Article in English | MEDLINE | ID: mdl-28069241

ABSTRACT

2-Methacryloyloxy ethyl trimethyl ammonium chloride (TMA) is a potent polymeric plasma DNA (pDNA) carrier. The present study shows that TMA/pDNA polyplexes could be internalized into cells efficiently, but could not mediate gene transfection on its own. The transfection process of TMA/pDNA polyplexes is turned on only when ultrasound (US) was applied 4-8h after incubating TMA/pDNA polyplexes with target cells (with a gene expression 1000 times that of the immediate US group). US is a widely used physical method for gene delivery; its transfection efficiency can be significantly enhanced when combined with cationic polymer vectors. Traditionally, US is given simultaneously with genetic materials, carriers and microbubbles to exert maximal efficacy. The unique on-off phenomenon of TMA/pDNA polyplexes, controlled by US exposure, was found to relate to the endosomal escape effect of US since the polyplexes colocalized well with the lysosome marker if no US was given or was given at inappropriate times. The proposed delivery system using US and TMA carriers has potential in many pharmaceutical applications requiring precise temporal and spatial release control.


Subject(s)
DNA/chemistry , Drug Carriers/chemistry , Drug Liberation , Intracellular Space/metabolism , Quaternary Ammonium Compounds/chemistry , Ultrasonic Waves , Animals , DNA/genetics , DNA/metabolism , Mice , NIH 3T3 Cells , Transfection
20.
Langmuir ; 31(22): 6130-6, 2015 Jun 09.
Article in English | MEDLINE | ID: mdl-25985827

ABSTRACT

Polyethylenimine (PEI) and poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA) have both been used for DNA delivery. PDMAEMA has been shown to exhibit better gene transfection efficiency but lower expression ability than PEI. We mixed the two polymers at different ratios to investigate whether the resulting "dual" polyplex (PEI/PDMAEMA/DNA) could enhance both gene transfection efficiency and DNA expression ability. Experimental results showed a significant increase in DNA internalization and DNA expression for the PDMAEMA/PEI/DNA polyplexes at a ratio of 1:3 or 1:9 (PDMAEMA: PEI), depending on cell type, in comparison with PEI/DNA, PDMAEMA/DNA, and PDMAEMA/PEI/DNA at other ratios. PDMAEMA/PEI/DNA polyplexes did not reduce cell viability. In contrast to with the conventional approach using covalently modified PEI, the proposed "combination" approach provided a more convenient and effective way to improve transgene expression efficiency.


Subject(s)
DNA/genetics , Gene Transfer Techniques , Methacrylates/chemistry , Nylons/chemistry , Polyethyleneimine/chemistry , Transgenes/genetics , Animals , Cell Survival/drug effects , Cells, Cultured , Methacrylates/pharmacology , Mice , Molecular Structure , NIH 3T3 Cells , Nylons/pharmacology , Polyethyleneimine/pharmacology , Promoter Regions, Genetic/genetics
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