VSIG4 inhibits RANKL-induced osteoclastogenesis by enhancing Nrf2-dependent antioxidant response against reactive oxygen species production.

Osteoporosis is a prevalent systemic skeletal disorder, particularly affecting postmenopausal women, primarily due to excessive production and activation of osteoclasts. However, the current anti-osteoporotic drugs utilized in clinical practice may lead to certain side effects. Therefore, it is necessary to further unravel the potential mechanisms regulating the osteoclast differentiation and to identify novel targets for osteoporosis treatment. This study revealed the most significant decline in VSIG4 expression among the VSIG family members. VSIG4 overexpression significantly inhibited RANKL-induced osteoclastogenesis and bone resorption function. Mechanistically, both western blot and immunofluorescence assay results demonstrated that VSIG4 overexpression attenuated the expression of osteoclast marker genes and dampened the activation of MAPK and NF-κB signaling pathways. Furthermore, VSIG4 overexpression could inhibit the generation of reactive oxygen species (ROS) and stimulate the expression of Nrf2 along with its downstream antioxidant enzymes via interaction with Keap1. Notably, a potent Nrf2 inhibitor, ML385, could reverse the inhibitory effect of VSIG4 on osteoclast differentiation. In line with these findings, VSIG4 overexpression also mitigated bone loss induced by OVX and attenuated the activation of osteoclasts in vivo. In conclusion, our results suggest that VSIG4 holds promise as a novel target for addressing postmenopausal osteoporosis. This is achieved by suppressing osteoclast formation via enhancing Nrf2-dependent antioxidant response against reactive oxygen species production.

Inhibition of KIF11 ameliorates osteoclastogenesis via regulating mTORC1-mediated NF-κB signaling.

Osteoporosis, characterized by over-production and activation of osteoclasts, has become a major health problem especially in elderly women. In our study, we first tested the effect of Caudatin (Cau) in osteoclastogenesis, which is separated from Cynanchum auriculatum as a species of C-21 steroidal glyosides. The results indicated that Cau suppressed osteoclastogenesis in a time- and dose-dependent manner in vitro. Mechanistically, Cau was identified to inhibit NF-κB signaling pathway via modulation of KIF11-mediated mTORC1 activity. In vivo, by establishing an ovariectomized (OVX) mouse model to mimic osteoporosis, we confirmed that Cau treatment prevented OVX-induced bone loss in mice. In conclusion, we demonstrated that Cau inhibited NF-κB signaling pathway via modulation of KIF11-mediated mTORC1 activity to suppress osteoclast differentiation in vitro as well as OVX-induced bone loss in vivo. This provides the possibility of a novel prospective drug for osteoporosis remedies.

Extracellular vesicles metabolic changes reveals plasma signature in stage-dependent diabetic kidney disease.

OBJECTIVE: Early diagnosis of diabetic kidney disease (DKD) has long been a complex problem. This study aimed to analyze the metabolomic characteristics of plasma extracellular vesicles (EVs) at different stages of DKD in order to evaluate the metabolites of plasma EVs and select new biomarkers for the early diagnosis of DKD. PATIENTS AND METHODS: A total of 78 plasma samples were collected, including samples from 20 healthy controls, 20 patients with type 2 diabetes mellitus (T2DM), 18 patients with DKD stage III, and 20 patients with DKD stage IV. In addition, EVs were isolated for metabolomics analysis. RESULTS: The results identified differences in EV metabolomic characteristics in DKD patients at different stages, as well as significant differences in EV metabolomics between T2DM patients without DKD and patients with DKD. Ten Significantly differential metabolites were associated with the occurrence and progression of DKD. Uracil, LPC(O-18:1/0:0), sphingosine 1-phosphate, and 4-acetamidobutyric acid were identified as potential early biomarkers for DKD, showing excellent predictive performance. CONCLUSION: Uracil, LPC(O-18:1/0:0), sphingosine 1-phosphate, and 4-acetamidobutyric acid exhibited potential as suitable biomarkers for early DKD diagnosis. Unexpectedly, combining these four candidate metabolites resulted in enhanced predictive ability for DKD.

Highly Selective Purification of Plasma Extracellular Vesicles Using Titanium Dioxide Microparticles for Depicting the Metabolic Signatures of Diabetic Retinopathy.

Extracellular vesicle (EV) cargos with regular fluctuations hold the potential for providing chemical predictors toward clinical diagnosis and prognosis. A plasma sample is one of the most important sources of circulating EVs, yet the technical barrier and cost consumption in plasma-EV isolation still limit its application in disease diagnosis and biomarker discovery. Here, we introduced an easy-to-use strategy that allows selectively purifying small EVs (sEVs) from human plasma and detecting their metabolic alternations. Fe3O4@TiO2 microbeads with a rough island-shaped surface have proven the capability of performing efficient and reversible sEV capture owing to the phospholipid affinity, enhanced binding sites, and size-exclusion-like effect of the rough TiO2 shell. The proposed system can also shorten the separation procedure from hours to 20 min when compared with the ultracentrifugation method and yield approximately 108 sEV particles from 100 µL of plasma. Metabolome variations of sEVs among progressive diabetic retinopathy subjects were finally studied, observing a cluster of metabolites with elevated levels and suggesting potential roles of these sEV chemicals in diabetic retinopathy onset and progression. Such a scalable and flexible EV capture system can be seen as an effective analytical tool for facilitating plasma-based liquid biopsies.

Discovering the Secret of Diseases by Incorporated Tear Exosomes Analysis via Rapid-Isolation System: iTEARS.

Nanoscale small extracellular vesicles (sEVs, exosomes) in tears allow us to investigate the multisignatures of diseases. However, the translations of tear sEVs for biomarker discovery and clinical diagnostics are practically limited by low recovery, long processing time, and small sample volume. Here, we report an incorporated tear-exosomes analysis via rapid-isolation system (iTEARS) via nanotechnology to discover the secrets of ocular disorders and systemic diseases. We isolate exosomes rapidly with high yield and purity from a few teardrops (∼10 µL) within 5 min via nanoporous membrane-based resonators for the quantitative detection and biomarker discovery through proteomic and transcriptomic analysis. We have identified 904 proteins, among which 228 proteins are discovered, 426 proteins are detected from exosomes of dry eye disease, and demonstrate CALML5, KRT6A, and S100P for the classification of dry eye disease. We have also investigated 484 miRNAs in tear exosomes and show miR-145-5p, miR-214-3p, miR-218-5p, and miR-9-5p are dysregulated during diabetic retinopathy development. We believe iTEARS can be used for improving molecular diagnostics via tears to identify ocular disorders, systemic diseases, and numerous other neurodegenerative diseases and cancer.

Association between muscle mass, bone mineral density and osteoporosis in type 2 diabetes.

AIMS/INTRODUCTION: Type 2 diabetes mellitus is associated with an increased incidence of osteoporosis and sarcopenia. However, the relationship between osteoporosis and sarcopenia in patients with type 2 diabetes mellitus remains to be unclear. Appendicular skeletal muscle was adjusted by height (appendicular skeletal muscle mass [ASM]/height2 ) as a marker of sarcopenia. This study aimed to explore the relationship between ASM/height2 , osteoporosis and bone mineral density (BMD) in this population. MATERIALS AND METHODS: A total of 192 women and 225 men with type 2 diabetes mellitus were recruited. General information, laboratory and BMD data were collected. Spearman's correlation, multiple regression analyses and receiver operating characteristic curve analysis were used to explore the correlation between ASM/height2 , BMD and bone metabolism markers. RESULTS: Spearman's correlation analysis showed that ASM/height2 had a positive correlation with serum calcium and BMD (r = 0.209-0.404, P < 0.01). In multivariate regression analysis, we found significant correlations between ASM/height2 and total lumbar spine, hip and femur neck BMD. According to the receiver operating characteristic curve, ASM/height2 was the best marker of osteoporosis, with a cut-off value of 7.87 kg/m2 for men and 5.94 kg/m2 for women. When these cut-off values were used to identify sarcopenia, the risk of osteoporosis increased 6.036-fold in men and 4.079-fold in women, respectively. CONCLUSIONS: In patients with type 2 diabetes mellitus, ASM/height2 was positively correlated with BMD, and negatively correlated with osteoporosis.

The Association of Aspartate Aminotransferase/Alanine Aminotransferase Ratio with Diabetic Nephropathy in Patients with Type 2 Diabetes.

PURPOSE: To investigate the relationship between aspartate aminotransferase to alanine aminotransferase ratio (AST/ALT) and diabetic nephropathy (DN). PATIENTS AND METHODS: A total of 402 patients with type 2 diabetes mellitus were divided into three groups, such as normoalbuminuria (n = 196), microalbuminuria (n = 131) and macroalbuminuria (n = 75) groups. Basic information and laboratory results were collected. Serum AST/ALT, tumor necrosis factor-α (TNF-α), interleukin (IL)-2, IL-4, IL-6, IL-10 and interferon- γ (INF- γ) were also measured. DN was defined as microalbuminuria or macroalbuminuria. The estimated glomerular filtration rate (eGFR) was calculated using the following formula: 186 × (serum creatinine)-1.154× (age)-0.203× (0.742 if female). RESULTS: The AST/ALT in the macroalbuminuria group was higher than in the microalbuminuria and normoalbuminuria groups. The concentrations of tumor necrosis factor-α (TNF-α), IL-2, IL-4, IL-10 and INF-γ in the macroalbuminuria group were significantly higher than those in the two other groups. Multivariate logistical analysis showed that after adjusting confounding factors, TNF-α and high AST/ALT were independent risks for DN and macroalbuminuria. Furthermore, the AST/ALT had significantly positive correlation with TNF-α (r = 0.101, P = 0.048), IL-4 (r = 0.185, P = 0.005) and IL-6 (r = 0.274, P < 0.001) levels. CONCLUSION: This study showed that high AST/ALT was an independent risk factor for the DN. Additionally, AST/ALT was positively correlated with inflammation cytokines, such as TNF-α, IL-4 and IL-6 levels.

Morin attenuates osteoclast formation and function by suppressing the NF-κB, MAPK and calcium signalling pathways.

Morin is a natural compound isolated from moraceae family members and has been reported to possess a range of pharmacological activities. However, the effects of morin on bone-associated disorders and the potential mechanism remain unknown. In this study, we investigated the anti-osteoclastogenic effect of morin in vitro and the potential therapeutic effects on ovariectomy (OVX)-induced osteoporosis in vivo. In vitro, by using a bone marrow macrophage-derived osteoclast culture system, we determined that morin attenuated receptor activator of nuclear factor (NF)-κB ligand (RANKL)-induced osteoclast formation via the inhibition of the mitogen-activated protein kinase (MAPK), NF-κB and calcium pathways. In addition, the subsequent expression of nuclear factor of activated T cells c1 (NFATc1) and c-fos was significantly suppressed by morin. In addition, NFATc1 downregulation led to the reduced expression of osteoclastogenesis-related marker genes, such as V-ATPase-d2 and Integrin ß3. In vivo, results provided that morin could effectively attenuate OVX-induced bone loss in C57BL/6 mice. In conclusion, our results demonstrated that morin suppressed RANKL-induced osteoclastogenesis via the NF-κB, MAPK and calcium pathways, in addition, its function of preventing OVX-induced bone loss in vivo, which suggested that morin may be a potential therapeutic agent for postmenopausal osteoporosis treatment.

The association between parity and metabolic syndrome and its components in normal-weight postmenopausal women in China.

BACKGROUND: Studies analyzing the association between parity and normal-weight metabolic syndrome (MetS) in postmenopausal women of normal weight remain limited, this study aimed to explore the association between parity and MetS among Chinese normal-weight postmenopausal women. METHODS: In total, 776 normal-weight undiagnosed type 2 diabetes postmenopausal women who visited the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University for a routine health check-up between 1 January 2017 and 31 December 2019 were included in the cross-sectional study. All individuals had fully completed information records encompassing standardized electronic medical records, physical examinations, and biochemical measurements. Metabolic health was defined as fewer than 2 parameters of the MetS were present, in combination with normal weight. Continuous variables which were normally distributed were expressed as means and standard deviation. Comparisons among normally distributed continuous variables were made using one-way ANOVA while that among non-normal distribution parameters were made using Kruskal-Wallis. The association between parity and MetS was analyzed using multivariate logistic regression. All of the analyses were performed with SPSS statistical software (Version 23.0, SPSS, Inc., Chicago, IL, USA) and the statistical software package EmpowerStats ( http://www.empowerstats.com , X&Y Solutions, Inc., Boston, MA). RESULTS: After adjusting for potential confounding factors including hip circumference, parity was failed to show a significantly relationship with MetS in normal-weight women(P=0.054). Women with a higher parity (≥3) had an increased OR of abdominal obesity, while the OR (95% CI) of the parity 3 group was 2.06 (1.13, 3.77) and that of the parity ≥4 group was 3.08(1.42, 6.66) the P for trend was 0.002 after adjusting for potential confounding factors. No significant differences were detected for other metabolic disorders including high levels of triglycerides (TG), blood pressure, fasting plasma glucose (FPG), and decreased high-density lipoprotein cholesterol (HDL-C) in different parity groups. CONCLUSIONS: Higher parity was not associated with a higher risk of MetS in normal weight Chinese postmenopausal women. As for the components of MetS, only waist circumference was associated with multiparity even after controlling for hip circumference.

Serum Metrnl Level is Correlated with Insulin Resistance, But Not with ß-Cell Function in Type 2 Diabetics.

BACKGROUND Metrnl is a novel identified adipomyokine which might have therapeutic potential for metabolic and inflammatory diseases, including type 2 diabetes mellitus. We aimed to explore the associations of circulating Metrnl level with ß-cell function and insulin resistance (IR) and further explore the possible correlation between Metrnl and another adipomyokine named irisin in patients diagnosed type 2 diabetes. MATERIAL AND METHODS Our study recruited 59 participants with type 2 diabetes and 30 normal glucose tolerance (NGT) participants. We used enzyme-linked immunosorbent assay (ELISA) to measure serum levels of Metrnl and irisin. The associations of Metrnl level with indexes of ß-cell function and IR and irisin level were analyzed by multiple linear regression analysis or spearman correlation analysis. RESULTS Compared with NGT participants, serum Metrnl level was elevated in participants with type 2 diabetes: 210.30 pg/mL (range 105.94-323.91 pg/mL) versus 132.02 pg/mL (range 104.93-195.92 pg/mL). Metrnl level did not show significant correlation with ß-cell function-related indicators, but positively correlated with HOMA2-IR and negatively correlated with HOMA2-%S after controlling multiple covariates in participants with type 2 diabetes. Metrnl level was also not associated with obesity-related indicators (body mass index, waist circumference, body fat percentage, and visceral adipose tissue area) in the type 2 diabetes group. In addition, the correlation between Metrnl and irisin level was also not present (r=-0.159, P=0.229) in type 2 diabetes group. CONCLUSIONS Serum Metrnl level was associated with IR, but not with ß-cell function in participants with diagnosed type 2 diabetes.

Low-dose adefovir dipivoxil-induced hypophosphatemia osteomalacia in five chronic hepatitis B virus-infected patients. Is low-dose adefovir dipivoxil-induced nephrotoxicity completely reversible?

Adefovir dipivoxil (ADV) is one of the most important nucleostide analogues currently in use for the treatment of chronic hepatitis B virus (HBV) infection. Low-dose ADV-induced nephrotoxicity in most cases was reported to be reversible after the discontinuation of ADV or by decreasing the dose of ADV. In our study, we have 5 documented cases of low-dose ADV-induced hypophosphatemia osteomalacia with or without Fanconi syndrome which were diagnosed in our hospital between 2010 and 2017. Three patients were observed to have a full recovery after the discontinuation of ADV. Two patients had persistently elevated urine ß2-microglobulin levels and out of these two patients, one patient had persistent hypophosphatemia after the cessation of ADV. These cases illustrated that the use of low-dose ADV increased the risk of nephrotoxicity, and in some patients, low-dose ADV-induced nephrotoxicity was not completely reversible. Patients of East Asian origin, especially those with a low body mass index, were prone to a relatively higher risk of developing low-dose ADV-induced nephrotoxicity; therefore, it was worth paying attention to the side effects caused by low-dose ADV.

[CpG-ODN activation of TLR9 signaling pathways and NF-κB in STZ-induced diabetic rats].

OBJECTIVE: To observe the mRNA and protein expression of TLR9, NF-κB and serum level of Th1/Th2 cytokines when stimulated with different concentration of CpG-ODN in STZ-induced diabetic rats. METHODS: 40 SD male rats were randomly divided into four groups:normal control group (Group I), type 1 diabetes control group (Group II), low-dose CpG-ODN treated type 1 diabetes group (Group III), high dose CpG-ODN treated type 1 diabetes group (Group IV). 60 µg /kg and 120 µg /kg CpG-ODN were injected to rats of Group III and IV when inducing type 1 diabetes model.mRNA and protein levels of TLR9 and NF-κB in spleen and pancreas were detected by fluorescence quantitative PCR and Western blotting.Serum TNF-α, IL-6 and IFN-γ were measured by ELISA. RESULTS: TLR9 protein expression levels were much higher in spleen than in the pancreas among these four groups. In spleen, TLR9 and NF-κB mRNA and protein level were significantly higher in Group III and IV than those in Group I and II, and the expression level was higher in Group IV than in Group III. In pancreas, TLR9 and NF-κB protein level were significantly higher in Group III and IV than those in Group I and II, and the expression level was also higher in Group IV than Group III.Serum TNF-α and IFN-γ level in Group III and IV significantly higher than in Group I and II, and serum levels of TNF-α and IFN-γ in Group IV was higher than in Group III. CONCLUSIONS: CpG-ODN activation of TLR9-MyD88 signaling pathways results in dose-effect NF-κB stimulation in STZ-induced diabetic rats.