Visceral Adipose Tissue-derived Serine Protease Research Articles

Vaspin facilitates the proliferation and osteogenic differentiation of periodontal ligament stem cells.

To investigate whether visceral adipose tissue-derived serine protease inhibitor (vaspin) can alleviate the inhibitory effect of high-glucose (HG) culture on the proliferation and osteogenic differentiation of human periodontal ligament stem cells (PDLSCs) and to preliminarily explore the underlying mechanisms. High glucose produces damage to the regeneration of periodontal tissue of PDLSCs. The expression level of vaspin in periodontal tissue is high in periodontitis patients and effectively reduced after initial therapy of periodontal diseases. However, the effect of vaspin on PDLSCs remains unknown. PDLSCs were cultured in media augmented with 5.5 or 25.0 mM concentrations of glucose to elucidate the impact and mechanism of vaspin on PDLSCs under high glucose invitro. Proliferation was measured by Cell Counting Kit-8 (CCK8) assay. Osteogenesis of PDLSCs was assessed by alkaline phosphatase (ALP) staining, ALP activity, and Alizarin Red staining. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot (WB) were used to investigate the osteo-specific markers. Then, the molecular impact of vaspin in the presence/absence of HG on PDLSCs physiology was determined with TGF-β1/Smad signaling pathway as the main focus. It was revealed that the proliferation and osteogenic differentiation (OD) of PDLSCs under HG was reduced, and by adding vaspin the anti-osteogenic impact of HG was relieved. Moreover, vaspin enhanced TGF-β1/Smad signaling pathway activity. Pretreatment with TGF-β1 inhibitor blocked vaspin-triggered TGF-β1/Smad signal activation and minimized the vaspin-induced protective effect against HG-inhibited growth and OD. In summary, vaspin observably reduces HG-mediated inhibition of PDLSCs OD by modulating the TGF-β1/Smad signaling pathway. Vaspin may be a potential therapeutic for periodontal tissue regeneration in diabetic patients.

Adipokine vaspin maintains angiogenesis and neurological function during cerebral ischemia-reperfusion via suppressing endoplasmic reticulum stress.

Visceral adipose tissue-derived serine protease inhibitor (vaspin) is an adipokine. It has been reported that decreased serum vaspin levels are significantly associated with stroke severity and prognosis. This article aims to explore the theoretical feasibility of vaspin supplementation for cerebral ischemia-reperfusion (I/R) injury. The I/R mouse models were constructed by the middle cerebral artery occlusion (MCAO) method, and the effects of vaspin on cerebral infarction, neurological function, angiogenesis and endoplasmic reticulum (ER) stress were explored. To verify the mediation of ER stress in the regulation of vaspin, human brain microvascular endothelial cells (HBMECs) were subjected to ER stress agonist tunicamycin in vitro. The impacts of vaspin and tunicamycin on oxygen glucose deprivation/ recovery (OGD/R)-induced cell viability, apoptosis, and angiogenesis were examined. Vaspin inhibited blood-brain barrier breakdown and infarction occurred in the brain tissue of the I/R mice. Vaspin also enhanced cerebral neovascularization and reduced the apoptosis. Additional tunicamycin increased the apoptosis of HBMECs and inhibited angiogenesis, reversing the protective effect of vaspin on cells. Together, this study reveals that vaspin supplementation reduces cerebral infarction and works against neurological dysfunction. It maintains the survival and angiogenesis capacity of HBMECs by inhibiting ER stress.

Cornelian Cherry (Cornus mas L.) Fruit Extract Lowers SREBP-1c and C/EBPα in Liver and Alters Various PPAR-α, PPAR-γ, LXR-α Target Genes in Cholesterol-Rich Diet Rabbit Model.

Cornelian cherry (Cornus mas L.) fruits, abundant in iridoids and anthocyanins, are natural products with proven beneficial impacts on the functions of the cardiovascular system and the liver. This study aims to assess and compare whether and to what extent two different doses of resin-purified cornelian cherry extract (10 mg/kg b.w. or 50 mg/kg b.w.) applied in a cholesterol-rich diet rabbit model affect the levels of sterol regulatory element-binding protein 1c (SREBP-1c) and CCAAT/enhancer binding protein α (C/EBPα), and various liver X receptor-α (LXR-α), peroxisome proliferator-activated receptor-α (PPAR-α), and peroxisome proliferator-activated receptor-γ (PPAR-γ) target genes. Moreover, the aim is to evaluate the resistive index (RI) of common carotid arteries (CCAs) and aortas, and histopathological changes in CCAs. For this purpose, the levels of SREBP-1c, C/EBPα, ATP-binding cassette transporter A1 (ABCA1), ATP-binding cassette transporter G1 (ABCG1), fatty acid synthase (FAS), endothelial lipase (LIPG), carnitine palmitoyltransferase 1A (CPT1A), and adiponectin receptor 2 (AdipoR2) in liver tissue were measured. Also, the levels of lipoprotein lipase (LPL), visceral adipose tissue-derived serine protease inhibitor (Vaspin), and retinol-binding protein 4 (RBP4) in visceral adipose tissue were measured. The RI of CCAs and aortas, and histopathological changes in CCAs, were indicated. The oral administration of the cornelian cherry extract decreased the SREBP-1c and C/EBPα in both doses. The dose of 10 mg/kg b.w. increased ABCA1 and decreased FAS, CPT1A, and RBP4, and the dose of 50 mg/kg b.w. enhanced ABCG1 and AdipoR2. Mitigations in atheromatous changes in rabbits' CCAs were also observed. The obtained outcomes were compared to the results of our previous works. The beneficial results confirm that cornelian cherry fruit extract may constitute a potentially effective product in the prevention and treatment of obesity-related disorders.

A comparative evaluation of adipokine VASPIN in female obese and non-obese subjects with periodontitis and health

Abstract Introduction: Periodontitis and obesity are major health hazards. Adiposity stimulates cytokines which aggravate periodontitis. To balance this body secretes an anti-inflammatory adipokine-like visceral adipose tissue-derived serine protease inhibitor (VASPIN). Aims and Objectives: The study aimed to assess serum VASPIN levels in females with and without periodontitis, categorized by obesity status. Materials and Methods: Eighty female subjects with the age range of 35–44 years were included in this observational study. All have been categorized into four groups, 20 in each group. The division was based on the body mass index (BMI) and Russell’s Periodontal Index (PI). Group I-with BMI 18.5–24.9 kg/m2; without PD (non-obese without PD) Group II-with BMI 25-29.9 kg/m2; with PD (non-obese with PD). Group III -with BMI ≥30 kg/m2; without PD (obese without PD).Group IV with BMI ≥30 kg/m2; with PD (Obese with PD). Statistics Used: Serum VASPIN levels were compared in all the groups. Among the groups were analyzed with ANOVA, Bartlett’s test for homogeneity of variances, and Bonferroni test for multiple comparisons. Results: When VASPIN and BMI were correlated, higher levels were found in Group II, followed by Groups IV, III, and I. Serum VASPIN levels among the groups were statistically significant P < 0.0001. Conclusion: Serum VASPIN can be used for predicting the progression of periodontal inflammation associated with obesity and also can act as a good biomarker for the initial stages of obesity.

Levels and diagnostic values of serum visceral adipose tissue-derived serine protease inhibitor and secreted frizzle-related protein 5 in children with idiopathic short stature

Abstract Background: Idiopathic short stature (ISS) is a common type of short stature. We aimed to analyze the diagnostic values of serum visceral adipose tissue-derived serine protease inhibitor (Vaspin) and secreted frizzle-related protein 5 (SFRP5) for ISS children. Methods: Sixty-five ISS children treated from February 2019 to June 2022 were selected as an ISS group, while another 65 healthy children receiving physical examination in the same period were selected as a healthy group. Their general data, physical development status, levels of serum Vaspin and SFRP5, and levels of serum growth hormone-releasing hormone (GHRH)/growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis-related indicators were compared. Results: The ISS group had lower body height, body weight, bone age, growth velocity and serum SFRP5 level and higher serum Vaspin level than those of the healthy group (P<0.05). The levels of serum GHRH, GH and IGF-1 were lower in the ISS group than those in the healthy group (P<0.05). Body height, body weight, bone age, growth velocity, and levels of GHRH, GH and IGF-1 were negatively correlated with serum Vaspin level (r<0, P<0.05) but positively correlated with serum SFRP5 level (r>0, P<0.05). The areas under the ROC curves of serum Vaspin and SFRP5 and their combination for the diagnosis of ISS were 0.871 [95% confidence interval (CI): 0.812-0.929], 0.880 (95% CI: 0.824-0.935) and 0.942 (95% CI: 0.907-0.977), respectively. Conclusions: Children with ISS have a higher level of serum Vaspin but a lower level of SFRP5, and the combined detection has a higher diagnostic value for ISS.

Clinical study of serum visceral adipose tissue-derived serine protease inhibitor (Vaspin) concentration and some biochemical parameters in Diabetic mellitus type 2 patients

Clinical study of serum visceral adipose tissue-derived serine protease inhibitor (Vaspin) concentration and some biochemical parameters in Diabetic mellitus type 2 patients

A Notorious Trio! Inflammation, Metabolic Syndrome and Vitiligo.

There is evidence to support that vitiligo is linked to metabolic syndrome (MS), confirming its systemic nature. However, the underlying pathogenic mechanisms remain unknown. To reveal the possible association of MS with vitiligo. We also attempted to study the connection between some inflammatory markers and MS in vitiligo patients to evaluate their utility in predicting MS risk. The study included 100 vitiligo patients with an age range between 18 to 60 years and 100 controls with matched age, gender, and body mass index. All subjects were tested for MS components. Serum visceral adipose tissue-derived serine protease inhibitor (vaspin), fatty acid binding protein 4 (FABP4), vascular adhesion protein 1 (VAP-1), chitinase-3-like protein 1 (YKL-40), and high-sensitivity C-reactive protein (hs-CRP) were also measured. Regarding MS, it was observed in 22.0% of vitiligo patients and 2.0% of control subjects (P < 0.001). Serum FABP4, VAP-1, YKL-40, and hs-CRP concentrations were higher in patients than in the control group (P < 0.05 each), and their levels showed high sensitivity and specificity to differentiate MS when using the receiver operating characteristic (ROC). Levels of these markers, except serum vaspin, were significantly positively correlated with lipid profile markers (except high-density lipoprotein cholesterol) and fasting blood glucose levels (P < 0.05 each). MS was more common in vitiligo patients. The levels of the biomarkers studied were significantly higher in vitiligo patients. Furthermore, their levels accurately predicted MS in vitiligo patients. According to current research, these markers may be useful in assessing MS risk in vitiligo patients. Extensive research, however, is required.

Association between insulin, glucagon, high sensitive c-reactive protein, insulin resistance with visceral adipose tissue-derived serine protease inhibitor (VASPIN) in obese population

Background: Obesity is an inflammatory condition that results in an increase in high sensitive C-Reactive Protein (hs-CRP), a risk for insulin resistance (IR). Vaspin has the effect of increasing insulin receptor sensitivity and on the other hand is a compensatory response to insulin resistance, one of which is measured by homeostasis models assessment-insulin resistance (HOMA-IR). This study was an analytical cross-sectional observational design, to determine the association between insulin, glucagon, CRP, and HOMA-IR levels with serum vaspin in obesity. Method: This study is an analytical study with a cross-sectional design. Criteria of inclusion were subjects in the range 18-60 years Denpasar citizen with BMI above 25 kg/m2 and willing to be involved in this study, while exclusion criteria were with either chronic conditions or acute inflammation such as infection, cancer, tumor, or chronic disease which is altered and threatening life. Correlation tests using spearman analysis. Results: From 131 obese subjects in this study, there were 72 (55%) men and 59 (45%) women. Median age: 33 (22-57) years, fasting insulin: 8.90 (2.20-74.50) ìIU/mL, glucagon: 48.10 (7.58-293.90) pq/mL, hs-CRP: 1.90 (0.20-9.50) mg/L, HOMA-IR: 2 (0.50-23.15), and vaspin levels: 0.16 (0.04-1.46) ng/mL. There was a significant positive correlation between HOMA-IR, insulin and glucagon with vaspin (r = 0.20, p = 0.020; r = 0.20, p = 0.022; and r = 0.28, p = 0.001), and a significant negative correlation between hs-CRP and vaspin (r = -0.24, p = 0.005) in obesity. In the path analysis, there was a direct and total negative effect of hs-CRP on vaspin (coefficient = -0.19; p = 0.027 and coefficient = -0.02; p = 0.038). Conclusion: This study shows a positive association between insulin, glucagon, and HOMA-IR with serum vaspin, while CRP is negatively associated with serum vaspin in obesity.

The search for systemic biomarkers for monitoring degenerative lumbar spinal disorders

ObjectivesIn our previous study, we reported that low back pain (LBP) severity and disability significantly correlate with body composition and several blood biochemical factors. Herein, we tested the hypothesis that these covariates are associated with anatomical deformations of the lumbar spine, in particular, radiographic facet joint osteoarthritis (FJOA) and lumbar disc degeneration (LDD) features important contributors to LBP. MethodsCT and MRI images of the lumbar spine were obtained from 200 individuals suffering from LBP-sciatica. We examined the FJOA and total LDD score - the sum of the scores of the three radiographic features (intervertebral disc herniation, osteophythosis and spondylolisthesis) at the L1 - S1 vertebral levels. By implementing a bioelectrical impedance analysis, we assessed the participants for body composition, specifically, extracellular water (ECW). Plasma levels of growth and differentiation factor 15 (GDF-15) and visceral adipose tissue-derived serine protease inhibitor (vaspin), were detected by ELISA. ResultsBy conducting a series of multivariable regression analyses, we report that the circulating levels of GDF-15, vaspin, and ECW are significantly and independently associated with FJOA scores [βGDF15 ​= ​0.38 ​± ​0.08, p ​= ​0.0001; βVASPIN ​= ​0.36 ​± ​0.07, p ​= ​0.000004; βECW ​= ​0.24 ​± ​0.07, p ​= ​0.002]. The levels of GDF-15 (β ​= ​0.30 ​± ​0.10, p ​= ​0.007) and ECW (β ​= ​0.20 ​± ​0.09, p ​= ​0.03) were also found significantly associated with the LDD scores. ConclusionThe obtained new data suggest that GDF-15, vaspin and ECW may serve as biomarkers for FJOA and LDD phenotypes.

Vaspin alleviates the lncRNA LEF1-AS1-induced osteogenic differentiation of vascular smooth muscle cells via the Hippo/YAP signaling pathway

Vascular calcification (VC) is closely related to higher cardiovascular mortality and morbidity, and vascular smooth muscle cell (VSMC) switching to osteogenic-like cells is crucial for VC. LncRNA LEF1-AS1 promotes atherosclerosis and dental pulp stem cells calcification, while its role in VC remains unknown. Visceral adipose tissue-derived serine protease inhibitor (vaspin) is an adipokine regulating bone metabolism. However, the relationship between vaspin and VC is still unclear. We aimed to explore the role of LEF1-AS1 on VSMC osteogenic transition, whether vaspin inhibited LEF1-AS1-mediated osteogenic differentiation of VSMCs, and the responsible mechanism. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting analysis indicated that LEF1-AS1 overexpression significantly upregulated osteogenic marker Runt-related transcription factor-2 (RUNX2) level and downregulated VSMC contractile marker α-smooth muscle actin (α-SMA) level. Alizarin red staining, alkaline phosphatase (ALP) staining, ALP activity assay, and calcium content assay also suggested that LEF1-AS1 overexpression promoted calcium deposition in VSMCs. However, vaspin treatment abolished this phenomenon. Mechanistically, LEF1-AS1 markedly decreased phosphorylated YAP level, while vaspin reversed LEF1-AS1-induced phosphorylated YAP decline. Our results revealed that LEF1-AS1 accelerated the osteogenic differentiation of VSMCs by regulating the Hippo/YAP pathway, while vaspin eliminated the LEF1-AS1-meditated VSMCs osteogenic phenotype switch.

Visceral Adipose Tissue-Derived Serine Protease Inhibitor (VASPIN) as A Prognostic Marker in Systemic Hypertension

Visceral Adipose Tissue-Derived Serine Protease Inhibitor (VASPIN) as A Prognostic Marker in Systemic Hypertension

New insights into cell apoptosis and proliferation: the potential role of vaspin.

Vaspin, also known as visceral adipose tissue-derived serine protease inhibitor; expression of this adipokine has been confirmed in many parts of the body like the hypothalamus, pancreas, thyroid gland, ovaries, placenta, and testes, where it may play a crucial role in osteogenesis, steroidogenesis, the formation of blood vessels, and food intake. In addition, there are many studies supporting an interaction between vaspin and cell proliferation and apoptosis, which are crucial processes for maintaining homeostasis of the body. Vaspin has an anti-apoptotic effect in ovarian cells, osteoblasts, macrophages, aortic endothelial cells, hepatocellular carcinoma cells, and cardiomyocytes. On the other hand, vaspin has no effect on apoptosis in aortic smooth muscle cells and cardiomyocytes. Interestingly, vaspin also promotes proliferation in normal and cancerous ovarian cells, pre-adipocytes, hepatocellular carcinoma cells, and bone mesenchymal stem cells, although other studies showed that this adipokine reduces the proliferation of aortic, and vascular smooth muscle cells. Furthermore, vaspin has no effect on the proliferation of chondrocytes, osteoblasts, macrophages, pre-adipocytes, umbilical vein endothelial cells, and coronary artery smooth muscle cells. Dysfunction and dysregulation in the apoptosis/proliferation ratio may lead to cancer development and progression as well as pathogenesis of many diseases. The molecular mechanism of vaspin action on cell apoptosis and proliferation is reviewed in this paper.

Levels and clinical significance of serum homocysteine (Hcy), high-density lipoprotein cholesterol (HDL-C), vaspin, and visfatin in elderly patients with different types of coronary heart disease.

To investigate the levels and clinical significance of serum homocysteine (Hcy), high-density lipoprotein cholesterol (HDL-C), visceral adipose tissue-derived serine protease inhibitor (vaspin), and visceral fat-specific adipokine (visfatin) in elderly patients with different types of coronary heart disease (CHD). A total of 208 elderly patients with CHD admitted to our hospital were selected as the observation group, and 57 healthy volunteers who received physical examinations during the same period were selected as the healthy control group. The patients in the observation group were divided into a stable angina pectoris (SAP) group, an unstable angina pectoris (UAP) group, and an acute myocardial infarction (AMI) group according to their clinical diagnosis. The levels of serum Hcy, HDL-C, vaspin, visfatin, and coronary angiography Gensini scores were compared among the CHD subgroups and the healthy control group. Pearson linear correlation analysis was used to analyze the correlation between levels of serum Hcy, HDL-C, vaspin, and visfatin with Gensini scores in elderly patients with different types of CHD. The levels of serum Hcy and visfatin in the observation group were significantly higher than those in the healthy control group (P<0.05), while the levels of serum HDL-C and vaspin were significantly lower than those in the healthy control group (P<0.05). There were statistically significant differences in the levels of serum Hcy, vaspin, and visfatin among the CHD subgroups (P<0.05). There were statistically significant differences in the Gensini scores and number of stenotic coronary arteries among the CHD subgroups (P<0.05). Pearson linear correlation analysis showed that the levels of serum Hcy, HDL-C, vaspin, and visfatin in the SAP group were not significantly correlated with Gensini scores (P>0.05). However, the levels of serum Hcy and visfatin in the UAP and AMI groups were positively correlated with Gensini scores (P<0.05), the level of serum vaspin was negatively correlated with Gensini scores (P<0.05). The levels of serum Hcy, vaspin, and visfatin vary according to the different types of CHD and are correlated with the degree of coronary artery stenosis. As such, these serum levels can be used as sensitive indicators for early detection and disease evaluation.

A Vaspin\u2013HSPA1L complex protects proximal tubular cells from organelle stress in diabetic kidney disease

Proximal tubular cells (PTCs) are crucial for maintaining renal homeostasis, and tubular injuries contribute to progression of diabetic kidney disease (DKD). However, the roles of visceral adipose tissue-derived serine protease inhibitor (vaspin) in the development of DKD is not known. We found vaspin maintains PTCs through ameliorating ER stress, autophagy impairment, and lysosome dysfunction in DKD. Vaspin−/− obese mice showed enlarged and leaky lysosomes in PTCs associated with increased apoptosis, and these abnormalities were also observed in the patients with DKD. During internalization into PTCs, vaspin formed a complex with heat shock protein family A (Hsp70) member 1 like (HSPA1L) as well as 78 kDa glucose-regulated protein (GRP78). Both vaspin-partners bind to clathrin heavy chain and involve in the endocytosis. Notably, albumin-overload enhanced extracellular release of HSPA1L and overexpression of HSPA1L dissolved organelle stresses, especially autophagy impairment. Thus, vapsin/HSPA1L-mediated pathways play critical roles in maintaining organellar function of PTCs in DKD.

The role of vaspin in porcine corpus luteum.

Vaspin, visceral adipose tissue-derived serine protease inhibitor, plays important roles in inflammation, obesity, and glucose metabolism. Our recent research has shown the expression and role of vaspin in the function of ovarian follicles. However, whether vaspin regulates steroidogenesis and luteolysis in the corpus luteum (CL) is still unknown. The aim of this study was first to determine the expression of vaspin and its receptor GRP78 in porcine CL at the early, middle, and late stages of the luteal phase. Next, we investigated the hormonal regulation of vaspin levels in luteal cells in response to luteinizing hormone (LH), progesterone (P4), and prostaglandin PGE2 and PGF2α. Finally, we determined vaspin's direct impact on luteal cells steroidogenesis, luteolysis and kinases phosphorylation. Our results are the first to show higher vaspin/GRP78 expression in middle and late vs early stages; immunohistochemistry showed cytoplasmic vaspin/GRP78 localization in small and large luteal cells. In vitro, we found that LH, P4, PGE2, and PGF2α significantly decreased vaspin levels. Furthermore, vaspin stimulated steroidogenesis by the activation of the GRP78 receptor and protein kinase A (PKA). Also, vaspin increased the ratio of luteotropic PGE2 to luteolytic PGF2α secretion via GRP78 and mitogen-activated kinase (MAP3/1). Moreover, vaspin, in a dose-dependent manner, decreased GRP78 expression, while it, in a time-dependent manner, increased kinases PKA and MAPK3/1 phosphorylation. Taken together, we found that vaspin/GRP78 expression depends on the luteal phase stage and vaspin affects luteal cells endocrinology, indicating that vaspin is a new regulator of luteal cells steroidogenesis and CL formation.

Circulating Levels of Visceral Adipose Tissue-Derived Serine Protease Inhibitor (Vaspin) Appear as a Marker of Musculoskeletal Pain Disability.

Musculoskeletal pain (MSP), specifically low back pain (LBP), is often associated with several adipose tissue-derived cytokines (adipokines) and body composition, but their correlations with the LBP-related disability/severity phenotypes remain poorly understood. In this cross-sectional study, two self-reported validated questionnaires were used to collect back pain and disability data in an ethnically homogeneous family-based population sample (N = 1078). Plasma levels of relatively new adipokines, vaspin and adipsin, were detected by ELISA. Body composition parameters, including fat, skeletal muscle mass, extracellular water (ECW), and others were assessed through bioelectrical impedance analysis (BIA) technology. Statistical analysis was conducted, accounting for the familial composition of the sample. The multiple regression analyses with four LBP-related phenotypes as dependent variables consistently showed, for the first time, the significant associations with vaspin levels, regardless of other covariates. The odds ratios (OR)/SD ranged between 1.24 (95%CI = 1.03–1.50) and 1.33 (95%CI = 1.07–1.64), depending on the LBP phenotype. Among the tested body composition covariates, only ECW levels displayed consistent and highly significant associations with all tested LBP phenotypes (OR from 1.43, 95%CI = 1.14–1.79 to 1.68, 95%CI = 1.26–2.24). The results clearly suggest that circulating concentrations of vaspin and ECW levels could serve as biomarkers of MSP/LBP severity and complications.

Insulin induces expression of the hepatic vaspin gene.

Visceral adipose tissue-derived serine protease inhibitor (vaspin), initially identified in the visceral adipose tissue, is an adipokine that improves endoplasmic reticulum stress in obesity or insulin sensitivity and glucose tolerance. However, the transcriptional regulation of the hepatic vaspin gene remains elusive. We have previously shown that CCAAT-enhancer-binding protein α, a transcription factor of the basic leucine zipper class, positively regulates the vaspin gene. The present study aimed to investigate the nutritional or hormonal regulators of vaspin expression in the liver. For the fasting and refeeding study, mice in the fasting group were subjected to fasting for 24 h and then sacrificed. Mice in the refeeding group were subjected to fasting for 24 h and then refed with a 50% (w/w) sucrose/MF diet for further 24 h and then sacrificed. For the streptozotocin (STZ) study, STZ (50 mg/kg) was intraperitoneally injected into C57BL/6JJc1 mice for 5 d. Hepatic vaspin was repressed due to fasting for 24 h and was induced upon refeeding with a high-sucrose diet. In studies on liver-specific C/EBPα-deficient mice, C/EBPα was not involved in the induction of hepatic vaspin upon refeeding. In addition, the depletion of insulin by streptozotocin treatment markedly decreased hepatic vaspin expression. Finally, fasting-repressed vaspin expression in the liver was significantly increased by direct injection of insulin into fasting mice. In conclusion, our results suggest that insulin is a positive regulator of hepatic vaspin expression.

Vaspin Attenuates High Glucose-Induced Inflammation and Apoptosis in Human Retinal Pigment Epithelium Cell

Diabetic retinopathy (DR) is identified as a serious microvascular complication of diabetes mellitus (DM). Vaspin (visceral adipose tissue-derived serine protease inhibitor) is known as a novel adipokine that associated with pathological process of DM. The present study aims to investigate the underlying mechanism related to the role of vaspin in the pathogenesis if DR. In present study, vaspin treatment attenuated high glucose-induced cell injury and inflammation in ARPE-19 cells. In addition, vaspin suppressed oxidative stress status and cell apoptosis in ARPE-19 cells with high glucose challenge. Furthermore, inactivation of Nod-like receptor P3 (NLRP3) inflammasome pathway may be associated with the anti-inflammation, antioxidant and anti-apoptosis activities of vaspin. Together our findings suggest that vaspin protected against inflammation and cell apoptosis in the pathological process of DR. Hence, vaspin may represent as an effective agent for clinical therapy of DR.

In Vitro Effects of Vaspin on Porcine Granulosa Cell Proliferation, Cell Cycle Progression, and Apoptosis by Activation of GRP78 Receptor and Several Kinase Signaling Pathways Including MAP3/1, AKT, and STAT3.

Vaspin, a visceral adipose tissue-derived serine protease inhibitor, is expressed in the porcine ovary; it induces the activation of various kinases and steroidogenesis. The aim of this study was to examine the effect of vaspin on granulosa (Gc) proliferation, cell cycle regulation, and apoptosis. Porcine Gc was incubated with vaspin (0.01–10 ng/mL) for 24 to 72 h, proliferation was measured using alamarBlue assay, cell cycle progression was assessed using flow cytometry, and cyclin (D, E, and A) protein expression was measured using immunoblotting. Apoptosis was assessed by measuring caspase activity using Caspase-glo 3/7 assay. Furthermore, histone-associated DNA fragments levels were measured using a cell-death detection ELISA; BAX (bcl-2-like protein 4), BCL2 (B-cell lymphoma 2), caspases (-3, -8, and -9), p53 mRNA, and protein expression were assessed using real time PCR and immunoblotting. We found that vaspin significantly enhanced Gc proliferation and cell cycle progression into the S and G2/M phases and decreased apoptosis. We observed that siRNA silencing of the glucose-regulated protein (GRP78) receptor and pharmacological inhibitors of mitogen-activated kinase (MAP3/1/ERK1/2), Janus kinase (STAT3) and protein kinase B (AKT) blocked the ability of vaspin cell proliferation and enhanced caspase-3/7 activities. These results suggest that vaspin via mitogenic effect on porcine Gc acts as a new regulator of ovarian growth, development, or folliculogenesis.

Vaspin in the pig ovarian follicles: expression and regulation by different hormones.

Vaspin, also known as visceral adipose tissue-derived serine protease inhibitor, is a member of the serine protease inhibitor family. Its expression is associated with obesity, insulin resistance and type 2 diabetes, and elevated concentration is observed in polycystic ovary syndrome. However, vaspin has never been studied in the ovary. Here, we identified vaspin in two prolific breeds of pigs: fat Meishan (MS) and lean Large White (LW). We then investigated the molecular mechanism involved in the regulation of its expression in response to gonadotropins, insulin, insulin-like growth factor type 1 (IGF-1) and steroids (progesterone, testosterone and oestradiol) in ovarian follicles cells. Using real-time PCR and Western blot, we found higher vaspin mRNA and protein expression in the ovarian follicles and adipose tissue at 10-12 days of the oestrous cycle in MS compared to LW. Moreover, vaspin expression, as well as its concentration in plasma and follicular fluid, decreased in ovarian follicles of LW during days of the oestrous cycle, while the opposite results were noted in MS. Immunohistochemistry showed vaspin in granulosa, theca, cumulus cells and oocytes as well as in adipocytes. Vaspin level in the ovary increased by gonadotropin, insulin, IGF-1 and steroids stimulation through kinases JAK/Stat, ERK1/2, PI3K and AMPK, as well as factor NF-κB. These findings all show vaspin expression and regulation in the pig ovary, indicating vaspin as a new regulator in female reproduction. Future studies will be necessary for understanding the role of vaspin on ovarian physiology providing new insights into the pathology of ovaries.