Dysregulation of Lipid Droplet Protein Expression in Adipose Tissues and Association with Metabolic Risk Factors in Adult Females with Obesity and Type 2 Diabetes.

BACKGROUND: Adipocyte dysregulation of lipid droplet (LD) metabolism caused by altered expression of LD proteins contributes to obesity-related metabolic diseases. OBJECTIVES: We aimed to investigate whether expression levels of PLIN1, CIDEA, and CIDEC were altered in adipose tissues of women with obesity and type 2 diabetes and whether their alterations were associated with metabolic risk factors. METHODS: Normal-weight (NW; 18.5 kg/m2 < BMI ≤ 25 kg/m2; n = 43), nondiabetic obese (OB; BMI > 30 kg/m2; n = 38), and diabetic obese (OB/DM; BMI > 30 kg/m2, fasting glucose ≥ 126 mg/dL, HbA1c ≥ 6.5%; n = 22) women were recruited. Metabolic parameters were measured, and expressions of PLIN1, CIDEA, CIDEC, and obesity-related genes were quantified in abdominal subcutaneous (SAT) and visceral adipose tissues (VAT). Effects of proinflammatory cytokines, endoplasmic reticulum (ER) stress inducers, and metabolic improvement agents on LD protein gene expressions were investigated in human adipocytes. RESULTS: PLIN1, CIDEA, and CIDEC expressions were lower in SAT and higher in VAT in OB subjects relative to NW subjects; however, they were suppressed in both fat depots in OB/DM subjects relative to OB (P < 0.05). Across the entire cohort, whereas VAT PLIN1 (r = 0.349) and CIDEC expressions (r = 0.282) were positively associated with BMI (P < 0.05), SAT PLIN1 (r = -0.390) and CIDEA expressions (r = -0.565) were inversely associated. After adjustment for BMI, some or all of the adipose LD protein gene expressions were negatively associated with fasting glucose (r = -0.259 or higher) and triglyceride levels (r = -0.284 or higher) and positively associated with UCP1 expression (r = 0.353 or higher) (P < 0.05). In adipocytes, LD protein gene expressions were 55-70% downregulated by increased proinflammatory cytokines and ER stress but 2-4-fold upregulated by the metabolic improvement agents exendin-4 and dapagliflozin (P < 0.05). CONCLUSIONS: The findings suggest that reduction of adipose LD protein expression is involved in the pathogenesis of metabolic disorders in women with obesity and type 2 diabetes and that increasing LD protein expression in adipocytes could control development of metabolic disorders.

Endoplasmic reticulum stress increases LECT2 expression via ATF4.

Non-alcoholic fatty liver disease (NAFLD) is frequently associated with obesity, insulin resistance, and endoplasmic reticulum (ER) stress. Elevated circulating levels of the hepatokine leukocyte cell-derived chemotaxin-2 (LECT2) have also been noted in NAFLD; however, the mechanism underlying this association is unclear. To investigate a possible link between ER stress/unfolded protein response (UPR) signaling and LECT2 secretion, HepG2 cells were incubated with ER stress inducers with or without an ER stress-reducing chemical chaperone. Additionally, UPR pathway genes were knocked down and overexpressed, and a ChIP assay was performed. In diet-induced obese mice, hepatic expression of LECT2 and activating transcription factor 4 (ATF4) was measured. In HepG2 cells, LECT2 expression was increased by ER stressors, an effect blocked by the chemical chaperone. Among UPR pathway proteins, only knockdown of ATF4 suppressed ER stress-induced LECT2 expression, while overexpression of ATF4 enhanced LECT2 expression. The ChIP assay revealed that ATF4 binds to three putative binding sites on the LECT2 promoter and binding is promoted by an ER stress inducer. In steatotic livers of obese mice, LECT2 and ATF4 expression was concomitantly elevated. Our data indicate that activation of ER stress/UPR signaling induces LECT2 expression in steatotic liver; specifically, ATF4 appears to mediate upregulation of LECT2 transcription.

Soluble Cytoplasmic Expression and Purification of Immunotoxin HER2(scFv)-PE24B as a Maltose Binding Protein Fusion.

Human epidermal growth factor receptor 2 (HER-2) is overexpressed in many malignant tumors. The anti-HER2 antibody trastuzumab has been approved for treating HER2-positive early and metastatic breast cancers. Pseudomonas exotoxin A (PE), a bacterial toxin of Pseudomonas aeruginosa, consists of an A-domain with enzymatic activity and a B-domain with cell binding activity. Recombinant immunotoxins comprising the HER2(scFv) single-chain Fv from trastuzumab and the PE24B catalytic fragment of PE display promising cytotoxic effects, but immunotoxins are typically insoluble when expressed in the cytoplasm of Escherichia coli, and thus they require solubilization and refolding. Herein, a recombinant immunotoxin gene was fused with maltose binding protein (MBP) and overexpressed in a soluble form in E. coli. Removal of the MBP yielded stable HER2(scFv)-PE24B at 91% purity; 0.25 mg of pure HER2(scFv)-PE24B was obtained from a 500 mL flask culture. Purified HER2(scFv)-PE24B was tested against four breast cancer cell lines differing in their surface HER2 level. The immunotoxin showed stronger cytotoxicity than HER2(scFv) or PE24B alone. The IC50 values for HER2(scFv)-PE24B were 28.1 ± 2.5 pM (n = 9) and 19 ± 1.4 pM (n = 9) for high HER2-positive cell lines SKBR3 and BT-474, respectively, but its cytotoxicity was lower against MDA-MB-231 and MCF7. Thus, fusion with MBP can facilitate the soluble expression and purification of scFv immunotoxins.

DJ-1 Can Replace FGF-2 for Long-Term Culture of Human Pluripotent Stem Cells in Defined Media and Feeder-Free Condition.

Conventional human pluripotent stem cell (hPSC) cultures require high concentrations of expensive human fibroblast growth factor 2 (hFGF-2) for hPSC self-renewal and pluripotency in defined media for long-term culture. The thermal instability of the hFGF-2 mandates media change every day, which makes hPSC culture costly and cumbersome. Human DJ-1 (hDJ-1) can bind to and stimulate FGF receptor-1. In this study, for the first time, we have replaced hFGF-2 with hDJ-1 in the essential eight media and maintained the human embryonic stem cells (hESCs), H9, in the defined media at feeder-free condition. After more than ten passages, H9 in both groups still successfully maintained the typical hESC morphology and high protein levels of pluripotency markers, SSEA4, Tra1-60, Oct4, Nanog, and ALP. DNA microarray revealed that more than 97% of the 21,448 tested genes, including the pluripotency markers, Sox2, Nanog, Klf4, Lin28A, Lin28B, and Myc, have similar mRNA levels between the two groups. Karyotyping revealed no chromosome abnormalities in both groups. They also differentiated sufficiently into three germ layers by forming in vitro EBs and in vivo teratomas. There were some variations in the RT-qPCR assay of several pluripotency markers. The proliferation rates and the mitochondria of both groups were also different. Taken together, we conclude that hDJ-1 can replace hFGF-2 in maintaining the self-renewal and the pluripotency of hESCs in feeder-free conditions.

Soluble Prokaryotic Overexpression and Purification of Human GM-CSF Using the Protein Disulfide Isomerase b'a' Domain.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a member of the colony-stimulating factor (CSF) family, which functions to enhance the proliferation and differentiation of hematopoietic stem cells and other hematopoietic lineages such as neutrophils, dendritic cells, or macrophages. These proteins have thus generated considerable interest in clinical therapy research. A current obstacle to the prokaryotic production of human GM-CSF (hGM-CSF) is its low solubility when overexpressed and subsequent complex refolding processes. In our present study, the solubility of hGM-CSF was examined when combined with three N-terminal fusion tags in five E. coli strains at three different expression temperatures. In the five E. coli strains BL21 (DE3), ClearColi BL21 (DE3), LOBSTR, SHuffle T7 and Origami2 (DE3), the hexahistidine-tagged hGM-CSF showed the best expression but was insoluble in all cases at each examined temperature. Tagging with the maltose-binding protein (MBP) and the b'a' domain of protein disulfide isomerase (PDIb'a') greatly improved the soluble overexpression of hGM-CSF at 30 °C and 18 °C. The solubility was not improved using the Origami2 (DE3) and SHuffle T7 strains that have been engineered for disulfide bond formation. Two conventional chromatographic steps were used to purify hGM-CSF from the overexpressed PDIb'a'-hGM-CSF produced in ClearColi BL21 (DE3). In the experiment, 0.65 mg of hGM-CSF was isolated from a 0.5 L flask culture of these E. coli and showed a 98% purity by SDS-PAGE analysis and silver staining. The bioactivity of this purified hGM-CSF was measured at an EC50 of 16.4 ± 2 pM by a CCK8 assay in TF-1 human erythroleukemia cells.

Novel Bacterial Production of Two Different Bioactive Forms of Human Stem-Cell Factor.

Human stem-cell factor (hSCF) stimulates the survival, proliferation, and differentiation of hematopoietic cells by binding to the c-Kit receptor. Various applications of hSCF require the efficient and reliable production of hSCF. hSCF exists in three forms: as two membrane-spanning proteins hSCF248 and hSCF229 and truncated soluble N-terminal protein hSCF164. hSCF164 is known to be insoluble when expressed in Escherichia coli cytoplasm, requiring a complex refolding procedure. The activity of hSCF248 has never been studied. Here, we investigated novel production methods for recombinant hSCF164 and hSCF248 without the refolding process. To increase the solubility of hSCF164, maltose-binding protein (MBP) and protein disulfide isomerase b'a' domain (PDIb'a') tags were attached to the N-terminus of hSCF164. These fusion proteins were overexpressed in soluble form in the Origami 2(DE3) E. coli strain. These solubilization effects were enhanced at a low temperature. His-hSCF248, the poly-His tagged form of hSCF248, was expressed in a highly soluble form without a solubilization tag protein, which was unexpected because His-hSCF248 contains a transmembrane domain. hSCF164 was purified using affinity and ion-exchange chromatography, and His-hSCF248 was purified by ion-exchange and gel filtration chromatography. The purified proteins stimulated the proliferation of TF-1 cells. Interestingly, the EC50 value of His-hSCF248 was 1 pg/mL, 100-fold lower than 9 ng/mL hSCF164. Additionally, His-hSCF248 decreased the doubling time, increased the proportion of S and G2/M stages in the cell cycle, and increased the c-Myc expression at a 1000-fold lower concentration than hSCF164. In conclusion, His-hSCF248 was expressed in a soluble form in E. coli and had stronger activity than hSCF164. The molecular chaperone, MBP, enabled the soluble overexpression of hSCF164.

Depot-specific UCP1 expression in human white adipose tissue and its association with obesity-related markers.

BACKGROUND: This study investigated depot-specific mRNA expression of uncoupling protein 1 (UCP1) in human white adipose tissue (WAT) and its association with obesity-related markers. METHODS: We recruited 39 normal-weight, 41 nondiabetic obese, and 22 diabetic obese women. We measured UCP1 mRNA expression in abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT), and investigated the associations between UCP1 mRNA expression in VAT and SAT, and obesity-related markers including mRNA expression of leptin, adiponectin, CCAAT-enhancer-binding protein homologous protein (CHOP), and positive regulatory domain-containing protein 16 (PRDM16). We also evaluated UCP1 mRNA expression in differentiated human white adipocytes after treatment with various stressors and metabolic improvement agents in vitro. RESULTS: UCP1 mRNA in VAT was significantly higher than in SAT in all groups. UCP1 mRNA in SAT was negatively correlated with BMI, total abdominal fat area, visceral fat area, blood pressure, fasting glucose, insulin, HOMA-IR score, triglyceride, hsCRP, fasting leptin levels, and adipocyte size. UCP1 mRNA in SAT was positively correlated with fasting adiponectin levels. UCP1 mRNA in VAT was negatively correlated with visceral-to-subcutaneous fat ratio (VSR), fasting glucose, and triglyceride levels. In SAT, UCP1 mRNA was negatively correlated with mRNA expression of leptin and CHOP, and positively correlated with mRNA expression of adiponectin. The expression of PRDM16 was positively correlated with UCP1 mRNA in both VAT and SAT. UCP1 mRNA expression in differentiated human white adipocytes was significantly reduced after incubation with thapsigargin, tunicamycin, homocysteine, TNF-α, or IL-ß, and significantly increased after incubation with exendin 4, dapagliflozin, and telmisartan. CONCLUSIONS: This study demonstrated depot-specific mRNA expression of UCP1 and its association with obesity-related markers in human WAT. UCP1 mRNA in human white adipocytes was suppressed by inflammatory agents and enhanced by metabolic improvement agents. UCP1 in human WAT might participate in the pathogenesis of obesity-related metabolic diseases.

Bacterial overexpression and purification of soluble recombinant human serum albumin using maltose-binding protein and protein disulphide isomerase.

Human serum albumin (HSA), the most abundant serum protein in healthy humans, plays important roles in many physiological processes and has wide clinical and research applications. Despite several efforts to obtain recombinant HSA (rHSA) from bacterial and eukaryotic expression systems, a low-cost and high-yield method for rHSA production is not available. The large molecular weight and high disulphide content hamper the expression and production of rHSA using bacterial hosts. Hence, a strategy that uses a fusion technique and engineered Escherichia coli strains was employed to improve the expression of soluble rHSA in the bacterial cytoplasm. The solubilities of the b'a' domain of human protein disulphide isomerase (PDIb'a')- and maltose-binding protein (MBP)-tagged rHSA expressed in Origami 2 at 18 °C were notably increased by up to 90.1% and 96%, respectively. A simple and efficient protocol for rHSA purification was established and approximately 9.46 mg rHSA was successfully obtained from a 500-mL culture at 97% purity. However, rHSA was mostly obtained in soluble oligomeric form. By introducing a simple refolding and size-exclusion chromatography step, monomeric rHSA was obtained at 34% yield. Native polyacrylamide gel electrophoresis confirmed the similarity in the molecular weights between E. coli-derived monomeric rHSA and commercial monomeric HSA.

Gender Differences in the Effects of Job Control and Demands on the Health of Korean Manual Workers.

We used the job-demand-control model to answer our two research questions concerning the effects of working conditions on self-rated health and gender differences and the association between these working conditions and health among Korean manual workers. Since a disproportionate representation of women in nonstandard work positions is found in many countries, including Korea, it is important to examine how working conditions explain gender inequality in health. We used data from the 2008-2009 Korean National Health and Nutrition Examination Survey and analyzed a total sample of 1,482 men and 1,350 women using logistic regression. We found that job control was positively related to self-rated health, while both physical and mental job demands were negatively related to self-rated health. We also found significant interaction effects of job demands, control, and gender on health. Particularly, female workers' health was more vulnerable to mentally demanding job conditions. We discussed theoretical and practice implications based on these findings.

Effects of streptozotocin and unilateral nephrectomy on L-type Ca²âº channels and membrane capacitance in arteriolar smooth muscle cells.

Diabetes mellitus and hypertension are common diseases frequently coexisting. Although augmentation of L-type Ca(2+) channel (ICaL) activity has been reported in vascular smooth muscle cells (VSMCs) of a spontaneously hypertensive rat model, no study on ICaL has been conducted for coexisting hypertension and diabetes. Sprague Dawley rats were assigned to four groups: a sham-operated control group (CG), a unilateral nephrectomy group (UNG), a streptozotocin (STZ)-induced type 1 diabetic group (SDG) and a coexisting hypertension and diabetes group (DHG), which underwent nephrectomy and received STZ injection. Blood pressure (BP) was significantly lower in the CG than in the other three groups. The membrane capacitance of VSMCs was nearly doubled in the SDG and DHG but not in the UNG. The ICaL was increased approximately 2-fold in both the UNG and SDG and approximately 4-fold in the DHG. The current density of ICaL was increased approximately 2-fold in the UNG and DHG, while no significant increase was seen in the SDG. The rate of Ca(2+) removal was inhibited significantly, by ~33 %, in the DHG. In conclusion, the effects of hypertension and diabetes on ICaL were apparently additive, and the vascular consequences of combined diabetes and hypertension may be caused by an elevated ICaL and slowed Ca(2+) removal.

Soluble overexpression and purification of bioactive human CCL2 in E. coli by maltose-binding protein.

Human chemokine (C-C motif) ligand 2 (hCCL2) is a small cytokine in the CC chemokine family that attracts monocytes, memory T lymphocytes, and natural killer cells to the site of tissue injury- or infection-induced inflammation. hCCL2 has been implicated in the pathogeneses of diseases characterized by monocytic infiltrates, including psoriasis, rheumatoid arthritis, atherosclerosis, multiple sclerosis, and insulin-resistant diabetes. The prokaryotic overexpression of hCCL2 has been investigated previously in an attempt to develop biomedical applications for this factor, but this has been hampered by protein misfolding and aggregation into inclusion bodies. In our present study, we screened 7 protein tags-Trx, GST, MBP, NusA, His8, PDI, and PDIb'a'-for their ability to allow the soluble overexpression of hCCL2. Three tags-MBP, His8, and PDI-solubilized more than half of the expressed hCCL2 fusion proteins. Lowering the expression temperature to 18 °C significantly further improved the solubility of all fusion proteins. MBP was chosen for further study based on its solubility, expression level, ease of purification, and tag size. MBP-CCL2 was purified using conventional chromatography and cleaved using TEV or Factor Xa proteases. Biological activity was assessed using luciferase and cell migration assays. Factor Xa-cleaved hCCL2 was found to be active and TEV-cleaved hCCL2 showed relatively less activity. This is probably because the additional glycine residues present at the N-terminus of hCCL2 following TEV digestion interfere with the binding of hCCL2 to its receptor.

Spatial and Compositional Variations in Fruit Characteristics of Papaya (Carica papaya cv. Tainung No. 2) during Ripening.

Papaya fruit (Carica papaya) has different degrees of ripening within each fruit, affecting its commercial market value. The fruit characteristics of "Tainung No. 2" Red papaya were investigated at the stem-end, middle, and calyx-end across 3 ripening stages and categorized based on fruit skin coloration: unripe at 16 weeks after anthesis (WAA), half-ripe at 18 WAA, and full-ripe at 20 WAA. The fruits maintained an elliptical shape during ripening with a ratio of 2.36 of the length to the width. The peel and pulp color changed from green to white to yellow during ripening, regardless of the three parts. In the pulp, soluble solid contents increased, and firmness decreased during ripening but did not differ among the three parts. Individual nutrient contents, including metabolites and minerals, changed dynamically between the ripening stages and fruit parts. Total carbohydrates and proteins, N, and K, were accumulated more at the stem-end during ripening; meanwhile, fructose, glucose, Mg, and Mn were accumulated more at the calyx-end. In the principal component analysis, ripening stages and fruit parts were distinctly determined by the first and second principal components, respectively. Understanding the nutrient and metabolite dynamics during ripening and their distribution within the fruit can help optimize cultivation practices, enhance fruit quality, and ultimately benefit both growers and consumers.

Crotamine-based recombinant immunotoxin targeting HER2 for enhanced cancer cell specificity and cytotoxicity.

Crotamine, one of the major toxins present in the venom of the South American rattlesnake Crotalus durissus terrificus, exhibits potent cytotoxic properties and has been suggested for cancer therapy applications. However, its selectivity for cancer cells needs to be improved. This study designed and produced a novel recombinant immunotoxin, HER2(scFv)-CRT, composed of crotamine and single-chain Fv (scFv) derived from trastuzumab targeting human epidermal growth factor receptor 2 (HER2). The recombinant immunotoxin was expressed in Escherichia coli and purified using various chromatographic techniques. The cytotoxicity of HER2(scFv)-CRT was assessed in three breast cancer cell lines, demonstrating enhanced specificity and toxicity in HER2-expressing cells. These findings suggest that the crotamine-based recombinant immunotoxin has the potential to expand the repertoire of recombinant immunotoxin applications in cancer therapy.

Photosynthetic response and antioxidative activity of 'Hass' avocado cultivar treated with short-term low temperature.

To investigate the effects of short-term low temperatures, three-year-old avocado (Persea americana cv. Hass) seedlings were treated with 1, - 2, or - 5 °C for 1 h and subsequently recovered in ambient condition for 24 h. Leaf color changes were investigated with chlorophyll, carotenoid, and phenolic contents. Photosynthetic responses were examined using gas exchange analysis. With H2O2 contents as oxidative stresses, enzymatic (ascorbate peroxidase, APX; glutathione reductase, GR; catalase, CAT; peroxidase, POD) and non-enzymatic antioxidant activities were determined using spectrophotometry. Leaves in the avocado seedlings started to be discolored with changes in the contents of chlorophyll a, carotenoids, and phenolics when treated with - 5 °C. However, the H2O2 content was not different in leaves treated with low temperatures. Photosynthetic activities decreased in leaves in the seedlings treated with - 5 °C. Of antioxidant enzymes, APX and GR have high activities in leaves in the seedlings treated with 1 and - 2 °C. In leaves in the seedlings treated with - 5 °C, the activities of all enzymes decreased. Non-enzymatic antioxidant activity was not different among leaves treated with low temperatures. These results indicated that APX and GR would play a critical role in withstanding chilling stress in 'Hass' avocado seedlings. However, under lethal temperature, even for a short time, the plants suffered irreversible damage with the breakdown of photosystem and antioxidant system.

TRIB3 Is Highly Expressed in the Adipose Tissue of Obese Patients and Is Associated With Insulin Resistance.

CONTEXT: The upregulation of TRIB3 (Tribbles homolog 3), a stress-inducible gene encoding a pseudokinase, has been implicated in the development of insulin resistance in the skeletal muscle and liver of patients with obesity and type 2 diabetes. However, there is little information regarding TRIB3 expression in human adipose tissue. OBJECTIVE: To investigate whether TRIB3 expression is dysregulated in human adipose tissue in the context of obesity and type 2 diabetes and whether TRIB3 expression in adipose tissues is associated with insulin resistance. METHODS: We measured metabolic parameters and TRIB3 expression in abdominal subcutaneous and visceral adipose tissue in obese (with or without type 2 diabetes) and normal-weight women. Regulation of TRIB3 expression was studied in human adipocytes. RESULTS: TRIB3 expression in both fat depots was higher in patients with obesity and/or type 2 diabetes; in addition, the expression level was significantly associated with insulin resistance. Incubating adipocytes under conditions mimicking the microenvironment of obese adipose tissue, including increased endoplasmic reticulum (ER) stress, induced TRIB3 expression. In human adipocytes, the overexpression of TRIB3 impaired insulin-stimulated protein kinase B (AKT) phosphorylation and caused dysregulation of the transcription of genes encoding bioactive molecules released from adipocytes, such as proinflammatory cytokines, adiponectin, and leptin. Pioglitazone, an insulin-sensitizing agent, reduced both these effects of TRIB3 and the ER stressor-induced expression of TRB3. CONCLUSION: Our data indicate that TRIB3 expression in adipose tissue is enhanced in patients with obesity and suggest that increased TRIB3 dysregulates adipocyte function, which may contribute to the development of insulin resistance.

Adipose tissue LECT2 expression is associated with obesity and insulin resistance in Korean women.

OBJECTIVE: Leukocyte cell-derived chemotaxin 2 (LECT2) is an obesity-upregulated hepatokine inducing skeletal muscle insulin resistance. The study's aim was to explore whether LECT2 is expressed in human adipose tissue and whether the expression is dysregulated during obesity and associated with obesity-related metabolic disorders. METHODS: This study measured metabolic parameters, serum LECT2, and expression of LECT2 and CD209, a gene encoding a putative receptor for LECT2, in abdominal subcutaneous and visceral adipose tissues in women with obesity (with or without type 2 diabetes) and women with normal weight. The expression/secretion of LECT2 and its putative effects were assessed in human adipocytes. RESULTS: Adipose tissue LECT2 mRNA and serum LECT2 were higher in women with obesity and were significantly correlated with parameters related to insulin resistance. LECT2 was mainly expressed by adipocytes. Both LECT2 and CD209 expression was higher in adipocytes from women with obesity. Incubating adipocytes with substances mimicking the microenvironment of obesity adipose tissue increased LECT2 expression/secretion. LECT2 treatment of adipocytes suppressed insulin-stimulated Akt phosphorylation; it reduced adiponectin (ADIPOQ) and increased leptin (LEP) expression in a CD209-dependent manner. CONCLUSIONS: This study demonstrates that LECT2 expression in adipose tissue is high in patients with obesity and associated with insulin resistance and suggests that adipocyte-derived LECT2 may contribute to adipose tissue dysfunction.

Relationship between vaspin gene expression and abdominal fat distribution of Korean women.

Visceral adipose tissue-derived serpin (vaspin) is a novel adipokine that is thought to have insulin-sensitizing effects. We investigated vaspin mRNA expression in abdominal adipose tissue and examined how gene expression related to abdominal fat distribution and metabolic parameters in Korean women. We measured anthropometric variables, metabolic parameters, serum vaspin concentration, and vaspin mRNA expression in abdominal adipose tissue obtained from women who underwent abdominal gynecological surgery and were aged 18-67 years (n = 85). Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) area were measured in 40 subjects using computed tomography (CT). Vaspin expression was analyzed by real-time quantitative RT-PCR according to abdominal fat distribution. Vaspin mRNA expression was greater in adipocytes than in stroma/vascular cells. In the total subjects, vaspin expression was significantly higher in SAT than in VAT. Vaspin expression in SAT in subcutaneous fat type (VSR ≤ 0.3) was significantly higher than in visceral fat type (VSR > 0.3), although vaspin expression in VAT was similar between subcutaneous and visceral fat type. There was a significant negative correlation between vaspin expression in SAT and VAT area (r = -0.55, p = 0.001). Serum vaspin concentration was significantly correlated with fasting insulin (r = 0.30, p = 0.02), HOMA-IR (r = 0.29, p = 0.02), and the ratio of vaspin expression in VAT to vaspin expression in SAT (r = 0.41, p = 0.04). Vaspin expression in abdominal adipose tissue was adipocyte-specific and vaspin expression in SAT decreased as VAT area increased.

Antinociceptive and Anti-Inflammatory Effects of Recombinant Crotamine in Mouse Models of Pain.

Crotamine, a toxin found in the venom of the South American rattlesnake Crotalus durissus terrificus, has been reported to have antinociceptive effects. We purified recombinant crotamine expressed in Escherichia coli and investigated its antinociceptive and anti-inflammatory effects using the hot-plate test, acetic-acid-induced writhing method, and formalin test in mice. Recombinant crotamine was administered intraperitoneally (0.04-1.2 mg kg-1) or intraplantarly (0.9-7.5 µg 10 µL-1) before the tests. The paw volume was measured with a plethysmometer. To evaluate the antagonistic and anti-inflammatory effects of naloxone, subcutaneous naloxone (4 mg kg-1) or intraplantar naloxone (5 µg 10 µL-1) was administered before recombinant crotamine. For tumor necrosis factor (TNF)-α assays, blood was drawn 3 h after formalin injection and measured using enzyme-linked immunosorbent assay. Intraperitoneal and intraplantar recombinant crotamine had antinociceptive and anti-inflammatory effects, neither of which were affected by pre-treatment with naloxone. The mean serum TNF-α levels were significantly lower in the intraperitoneal recombinant crotamine (0.4 and 1.2 mg kg-1) or intraplantar (2.5 and 7.5 µg 10 µL-1) recombinant crotamine groups than in the saline group and were not affected by naloxone pre-treatment. In conclusion, recombinant crotamine possesses significant antinociceptive and anti-inflammatory effects that do not appear to be related to the opioid receptor. The antinociceptive and anti-inflammatory effects of intraperitoneal or intraplantar recombinant crotamine are related to TNF-α.

TFEB-GDF15 axis protects against obesity and insulin resistance as a lysosomal stress response.

TFEB, a key regulator of lysosomal biogenesis and autophagy, is induced not only by nutritional deficiency but also by organelle stress. Here, we find that Tfeb and its downstream genes are upregulated together with lipofuscin accumulation in adipose tissue macrophages (ATMs) of obese mice or humans, suggestive of obesity-associated lysosomal dysfunction/stress in ATMs. Macrophage-specific TFEB-overexpressing mice display complete abrogation of diet-induced obesity, adipose tissue inflammation and insulin resistance, which is independent of autophagy, but dependent on TFEB-induced GDF15 expression. Palmitic acid induces Gdf15 expression through lysosomal Ca2+-mediated TFEB nuclear translocation in response to lysosomal stress. In contrast, mice fed a high-fat diet with macrophage-specific Tfeb deletion show aggravated adipose tissue inflammation and insulin resistance, accompanied by reduced GDF15 level. Finally, we observe activation of TFEB-GDF15 in ATMs of obese humans as a consequence of lysosomal stress. These findings highlight the importance of the TFEB-GDF15 axis as a lysosomal stress response in obesity or metabolic syndrome and as a promising therapeutic target for treatment of these conditions.

Micellization-induced amplified fluorescence response for highly sensitive detection of heparin in serum.

Fluorescence-based assays should be feasible in aqueous media for effectively detecting the biological factors. However, numerous sensors have limited signal transductions and low fluorescence quantum yields due to the ingerently reduced excited state energy of fluorophores in aqueous solution, which reduces their sensitivity. This necessitates a smart sensing approach with an amplified fluorescence response for analytes in aqueous solution. Herein, a new building block which self-assembles in aqueous media, giving a micellar sturcuture with the hydrophobic π-extended conjugated system at the core and hydrophilic groups at the periphery, was devised for the first time. We demonstrated that the aggregated fluorophores in a micelle induce amplified fluorescence quenching, in which the excited electron efficiently migrates through π-extended conjugated system in a micelle, as in a polymeric system. Such feature differentiates this sensing approach from the numerous fluorescence-based tools previously developed for sensitive detection. This new system exhibited highly sensitive signal transduction for specific analytes even under actual bioanalytical conditions.