Empagliflozin rescues lifespan and liver senescence in naturally aged mice.

Empagliflozin is currently known to decrease blood glucose levels, delay renal failure, and reduce the risk of cardiovascular death and all-cause mortality in patients with type 2 diabetes with cardiovascular disease. However, the effects of empagliflozin on the lifespan and health of naturally aged organisms are unclear. This study was designed to investigate the impacts and potential mechanisms of empagliflozin on lifespan and liver senescence in naturally aged mice. Our study revealed that empagliflozin improved survival and health in naturally aged mice. Empagliflozin extended the median survival of male mice by 5.9%. Meanwhile, empagliflozin improved learning memory and motor balance, decreased body weight, and downregulated the hepatic protein expression of P21, P16, α-SMA, and COL1A1. Empagliflozin modulates the structure of the intestinal flora, increasing the relative abundance of Lachnospiraceae, Ruminococcaceae, Lactobacillus, Blautia, and Muribaculaceae and decreasing the relative abundance of Erysipelotrichaceae, Turicibacter, and Dubosiella in naturally aged mice. Further exploration discovered that empagliflozin increased the concentration of SCFAs, decreased the levels of the inflammatory factors TNF-α, IL-6, and CXCL9, and regulated the PI3K/AKT/P21 and AMPK/SIRT1/NF-κB pathways, which may represent the underlying mechanisms involved in these beneficial hepatic effects. Taken together, the above results indicated that empagliflozin intervention could be considered a potential strategy for extending lifespan and slowing liver senescence in naturally aged mice.

Visceral adipose tissue and risk of diabetic nephropathy: A Mendelian randomization study.

OBJECTIVE: Previous observational studies have established a correlation between visceral adipose tissue (VAT) and diabetic nephropathy (DN). However, the causality of this association remains unclear. Therefore, the aim of this study was to investigate the causal association between VAT and DN by employing two-sample Mendelian randomization (MR) methods. METHODS: The primary MR approach employed was the random-effects inverse-variance weighted (IVW) method. Additionally, we employed alternative methods, including the weighted median (WM) approach, MR-Egger regression, and Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO). Sensitivity analyses were conducted to evaluate the robustness of the MR analyses. RESULTS: Genetically predicted higher VAT mass was causally associated with a higher risk of DN. The results of the MR analyses were as follows: IVW(Beta = 0.948, odds ratio (OR) = 2.581, 95 % confidence interval (CI) = 2.100-3.173, p = 1.980e-19), WM (Beta = 1.126, OR = 3.082, 95 % CI = 2.278-4.171, p = 2.997e-13), MR-Egger (Beta = 1.315, OR = 3.724, 95 % CI = 1.981-6.998, p = 6.446e-05), and MR-PRESSO (Beta = 0.914, OR = 2.493, 95 % CI = 2.292-2.695, p = 3.121e-16). No pleiotropy was detected (p = 0.230). CONCLUSIONS: This study provided genetic evidence that higher VAT mass was causally associated with a higher risk of DN.

Self-Adhesive, Biocompatible, Wearable Microfluidics with Erasable Liquid Metal Plasmonic Hotspots for Glucose Detection in Sweat.

Sweat is a noninvasive metabolite that can provide clinically meaningful information about physical conditions without harming the body. Glucose, a vital component in sweat, is closely related to blood glucose levels, and changes in its concentration can reflect the health status of diabetics. We introduce a self-adhesive, wearable microfluidic chip with erasable liquid metal plasmonic hotspots for the precise detection of glucose concentration in sweat. The self-adhesive, wearable microfluidic chip is made from modified polydimethylsiloxane (PDMS) with enhanced stickiness, enabling conformal contact with the skin, and can collect, deliver, and store sweat. The plasmonic hotspots are located inside the microfluidic channel, are generated by synthesizing silver nanostructures on liquid metal, and can be removed in the alkaline solution. It indicates the erasable and reproducible nature of the plasmonic hotspots. The detection method is based on surface-enhanced Raman spectroscopy (SERS), which allows for accurate detection of the glucose concentration. To enhance the sensitive detection of glucose, the SERS substrate is modified by 4-mercaptophenylboronic acid to achieve the limit of detection of 1 ng/L glucose, which is much lower than the physiological conditions (7.2-25.2 µg/L). The developed microfluidic chip is soft, stretchable, and nontoxic, bringing new possibilities to wearable sweat-sensing devices.

Visceral adipose tissue and risk of nonalcoholic fatty liver disease: A Mendelian randomization study.

OBJECTIVE: Observational studies have shown that visceral adipose tissue (VAT) can increase the risk of nonalcoholic fatty liver disease (NAFLD). However, the causality of this association remains unclear. Therefore, this study aimed to explore the causal association between VAT and NAFLD. DESIGN: We obtained single-nucleotide polymorphisms strongly associated with VAT (n = 325,153) from large-scale genome-wide association studies. Summary-level data for NAFLD (2275 cases and 375,002 controls) was available from the FinnGen consortium. We applied two-sample Mendelian randomization (MR) to determine the causal association between VAT and NAFLD. The random-effects inverse-variance weighted (IVW) method was used as the main MR approach, with alternate methods including the weighted median (WM) approach and MR-Egger regression. In addition, we conducted sensitivity analyses to assess the robustness of MR analyses. RESULTS: Genetically predicted higher VAT mass is causally associated with a higher risk of NAFLD. The three analysis results of MR were as follows: IVW (ß = 0.665, odds ratio [OR] = 1.944, 95% confidence interval [CI] = 1.482-2.550, p = 1.58e-06], WM (ß = 0.615, OR = 1.849, 95% CI = 1.272-2.689, p = 1.29e-03), and MR-Egger (ß = 1.250, OR = 3.490, 95% CI = 1.522-7.998, p = 3.52e-03). In the sensitivity analysis, the data showed heterogeneity (p < 0.05) but no pleiotropy (p = 0.145). CONCLUSION: This study provided genetic evidence that higher VAT mass causally associated with a higher risk of NAFLD. The amount of VAT could be reduced using a therapeutic strategy for managing NAFLD.

Interplant carbon and nitrogen transfers mediated by common arbuscular mycorrhizal networks: beneficial pathways for system functionality.

Arbuscular mycorrhizal fungi (AMF) are ubiquitous in soil and form nutritional symbioses with ~80% of vascular plant species, which significantly impact global carbon (C) and nitrogen (N) biogeochemical cycles. Roots of plant individuals are interconnected by AMF hyphae to form common AM networks (CAMNs), which provide pathways for the transfer of C and N from one plant to another, promoting plant coexistence and biodiversity. Despite that stable isotope methodologies (13C, 14C and 15N tracer techniques) have demonstrated CAMNs are an important pathway for the translocation of both C and N, the functioning of CAMNs in ecosystem C and N dynamics remains equivocal. This review systematically synthesizes both laboratory and field evidence in interplant C and N transfer through CAMNs generated through stable isotope methodologies and highlights perspectives on the system functionality of CAMNs with implications for plant coexistence, species diversity and community stability. One-way transfers from donor to recipient plants of 0.02-41% C and 0.04-80% N of recipient C and N have been observed, with the reverse fluxes generally less than 15% of donor C and N. Interplant C and N transfers have practical implications for plant performance, coexistence and biodiversity in both resource-limited and resource-unlimited habitats. Resource competition among coexisting individuals of the same or different species is undoubtedly modified by such C and N transfers. Studying interplant variability in these transfers with 13C and 15N tracer application and natural abundance measurements could address the eco physiological significance of such CAMNs in sustainable agricultural and natural ecosystems.

Inhibition of mGluR5 ameliorates lipid accumulation and inflammation in HepG2 cells.

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease characterized by ectopic lipid accumulation in hepatocytes. To date, no specific drug has been approved for its treatment. Metabotropic glutamate receptor 5 (mGluR5) has been showed expressed in hepatocytes and related to some liver diseases such as alcoholic steatosis. However, the function of mGluR5 in NAFLD is not clear. This work aims to investigate the effect and potential mechanism of mGluR5 in NAFLD. We found that mGluR5 expression was increased in the livers of HFD-fed mice and in palmitate-treated HepG2 cells. Suppression of mGluR5 by the specific antagonist MPEP could ameliorate palmitate-induced lipid accumulation, whereas the mGluR5 agonist CHPG promoted lipid deposition in the cells. Knockdown of mGluR5 by small interfering RNA further demonstrated that inhibition of mGluR5 could reduce lipid accumulation. Furthermore, our results revealed that mGluR5 regulated lipid metabolism by increasing the gene expression of lipogenesis. Inflammatory factors and phosphorylation levels of NF-κB-p65 and JNK were also tested in treated hepatocytes. mGluR5 promoted the inflammatory reaction and JNK phosphorylation. Inhibition of JNK signaling by JNK-IN-8 rescued CHPG-induced lipogenesis and inflammation. This study showed mGluR5 regulated lipid accumulation and inflammation in palmitic acid-treated HepG2 cells via the JNK signaling pathway. mGluR5 might be a potential drug target for NAFLD.

TXNIP Exacerbates the Senescence and Aging-Related Dysfunction of ß Cells by Inducing Cell Cycle Arrest Through p38-p16/p21-CDK-Rb Pathway.

Aims: Thioredoxin-interacting protein (TXNIP) is a crucial molecular promoter of oxidative stress and has been identified to be associated with cellular senescence. It is an important mediator of ß cell insulin secretion and has effects on ß cell mass. However, its role in ß cell senescence is unclear. The present study was designed to investigate the effects and mechanisms of TXNIP on the senescence and aging- and diet-related dysfunction of ß cells. Methods: Human pancreatic paraffin tissues and serum samples from different ages were collected to detect TXNIP expression. TXNIP-/- and C57BL/6J mice were fed either a normal chow diet (NCD) or a high-fat diet (HFD) until 5, 11, 14, or 20 months. The recapitulation experiment was conducted with TXNIP protein injection. MIN6 cells were transfected with LV-TXNIP and LV-siTXNIP. The biochemical indexes, ageing-related markers, cell cycle proteins, and pathways were examined both in vivo and in vitro. Results: TXNIP expression showed an age-related increase in ß cells and serum samples from humans. TXNIP significantly impaired glucose metabolism and insulin secretion in an age-dependent manner. TXNIP aggravated age-related and obesity-induced structural failure, oxidative stress, decreased proliferation, increased apoptosis in ß cells, and induced the cell cycle arrest. TXNIP interacted with p38 mitogen-activated protein kinase (p38MAPK) and modulated the p16/p21-CDK-Rb axis to accelerate ß cell senescence. Innovation and Conclusions: The present study demonstrated that TXNIP may exacerbate pancreatic ß cell senescence and age-related dysfunction by inducing cell cycle arrest through the p38-p16/p21-CDK-Rb pathway, in natural and pathological states. Antioxid. Redox Signal. 38, 480-495.

Funneliformis mosseae Improves Growth and Nutrient Accumulation in Wheat by Facilitating Soil Nutrient Uptake under Elevated CO2 at Daytime, Not Nighttime.

The concurrent effect of elevated CO2 (eCO2) concentrations and arbuscular mycorrhizal fungi (AMF) on plant growth, carbon (C), nitrogen (N), phosphorus (P) and potassium (K) accumulations in plant and soil is largely unknown. To understand the mechanisms of eCO2 and mycorrhization on wheat (Triticum aestivum) performance and soil fertility, wheat seedlings were grown under four different CO2 environments for 12 weeks, including (1) ambient CO2 (ACO2, 410/460 ppm, daytime/nighttime), (2) sole daytime eCO2 (DeCO2, 550/460 ppm), (3) sole nighttime eCO2 (NeCO2, 410/610 ppm), and (4) dual or continuous daytime/nighttime eCO2 ((D + N)eCO2, 550/610 ppm), and with or without AMF (Funneliformis mosseae) colonization. DeCO2, NeCO2 and (D + N)eCO2 generally significantly increased shoot and root biomass, plant C, N, P and K accumulation, soil invertase and urease activity, but decreased shoot and root N, P and K concentrations, and soil available N, P and K. Compared with non-AMF, AMF effects on above-mentioned characteristics were significantly positive under ACO2, DeCO2 and (D + N)eCO2, but negative on plant biomass, C, N, P and K accumulation under NeCO2. Overall, AMF colonization alleviated soil nutrient constraints on plant responses to DeCO2, while NeCO2 decreased AMF's beneficial effects on plants. These results demonstrated that an integration of AMF's benefits to plants under factual field DeCO2 and/or NeCO2 will be critical for managing the long-term consequence of future CO2 rising on global cropping systems.

Arbuscular Mycorrhization Enhances Nitrogen, Phosphorus and Potassium Accumulation in Vicia faba by Modulating Soil Nutrient Balance under Elevated CO2.

Effects of arbuscular mycorrhizal fungi (AMF), elevated carbon dioxide (eCO2), and their interaction on nutrient accumulation of leguminous plants and soil fertility is unknown. Plant growth, concentrations of tissue nitrogen (N), phosphorus (P), and potassium (K) in 12-week-old nodulated faba bean (Vicia faba, inoculated with Rhizobium leguminosarum bv. NM353), and nutrient use efficiency were thus assessed under ambient CO2 (410/460 ppm, daytime, 07:00 a.m.-19:00 p.m./nighttime, 19:00 p.m.-07:00 a.m.) and eCO2 (550/610 ppm) for 12 weeks with or without AM fungus of Funneliformis mosseae inoculation. eCO2 favored AMF root colonization and nodule biomass production. eCO2 significantly decreased shoot N, P and K concentrations, but generally increased tissue N, P and K accumulation and their use efficiency with an increased biomass production. Meanwhile, eCO2 enhanced C allocation into soil but showed no effects on soil available N, P, and K, while AM symbiosis increased accumulation of C, N, P, and K in both plant and soil though increased soil nutrient uptake under eCO2. Moreover, plant acquisition of soil NO3--N and NH4+-N respond differently to AMF and eCO2 treatments. As a result, the interaction between AM symbiosis and eCO2 did improve plant C accumulation and soil N, P, and K uptake, and an alternative fertilization for legume plantation should be therefore taken under upcoming atmosphere CO2 rising. Future eCO2 studies should employ multiple AMF species, with other beneficial fungal or bacterial species, to test their interactive effects on plant performance and soil nutrient availability in the field, under other global change events including warming and drought.

The relationship of mesencephalic astrocyte-derived neurotrophic factor with hyperlipidemia in patients with or without type 2 diabetes mellitus.

PURPOSE: This study was conducted to determine the relationship between mesencephalic astrocyte-derived neurotrophic factor (MANF) and lipid metabolism with or without type 2 diabetes mellitus (T2DM). METHODS: Human serum samples were collected from 58 normal controls (NC), 40 subjects with hyperlipidemia (HLD) without T2DM, and 42 subjects with HLD and T2DM. Their MANF levels were detected using an enzyme-linked immunosorbent assay (ELISA). Subgroup analysis was performed in the group with HLD and T2DM based on fasting blood glucose (FBG) > 8.22 vs. FBG ≤ 8.22. Furthermore, the relationship between MANF levels and lipid indices was analyzed. RESULTS: Serum MANF levels were found to be significantly higher in the HLD group, both with and without T2DM (5.62 (3.59-7.11) and 4.21 (2.87-6.11)), both P < 0.001, than in the NC (2.81(1.81-4.01). MANF levels were higher in those with FBG > 8.22 than that in those with FBG ≤ 8.22. In addition, in the HLD without T2DM group, MANF levels were negatively correlated with total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and age, while LDL-C and age were independently related to MANF levels. The area under the curve (AUC) in the ROC analysis of MANF for the diagnosis of HLD without T2DM and HLD with T2DM was 0.709 and 0.841, respectively (P < 0.001). CONCLUSION: Serum MANF levels increased in the HLD with or without T2DM groups and was associated with lipid and glucose metabolism. MANF may be a useful marker for predicting the development of dyslipidemia in T2DM.

Liraglutide protects pancreatic ß cells from endoplasmic reticulum stress by upregulating MANF to promote autophagy turnover.

AIMS: This study was conducted to determine the relationship between mesencephalic astrocyte-derived neurotrophic factor (MANF), autophagy and endoplasmic reticulum (ER) stress, and whether liraglutide (LRG) can protect ß cells, promote autophagy and alleviate ER stress by regulating MANF expression. MAIN METHODS: Human serum samples were collected from healthy controls (NC), simple hyperlipidemia (HLD), and newly diagnosed type 2 diabetes (T2D). The MANF levels were detected using ELISA. In vitro, after the mouse islet MIN6 cells were treated with glucose (GLU), palmitate (PA), thapsigargin (TG), LRG, and chloroquine (CQ), cell proliferation was detected using cell counting kit-8 (CCK-8), apoptosis-related protein cleaved caspase 3 (C-cas-3), ER stress, and autophagy-related proteins were detected by Western blotting, MANF, insulin, and C-cas-3 proteins were detected via immunofluorescence. Subcellular structures and autophagosomes were examined using electron microscopy. KEY FINDINGS: Compared with the NC group, the MANF levels in the HLD and T2D groups increased significantly. After ER stress induced by GLU, PA, and TG, cell viability decreased, while MANF, c-cas3, ERS, and autophagy-related proteins increased, which was related to the concentration of GLU, PA, and TG. Compared with the BSA group, the number of mitochondria and autophagosomes in the PA group increased and the mitochondria were damaged. In the PA and TG plus CQ groups, the effect was further exaggerated. But after co-treatment with LRG, the effects of GLU, PA, and TG were attenuated. SIGNIFICANCE: LRG protects islet ß cells from ER stress by upregulating MANF to promote autophagy turnover.

Generation of endoderm lineages from pluripotent stem cells.

Definitive endoderm is the cellular precursor to respiratory- and digestive-related organs such as lungs, stomach, liver, pancreas and intestine. Endodermal lineage cells derived from pluripotent stem cells (PSCs) in vitro are a potentially unlimited resource for regenerative medicine. These cells are useful tools for studying the physiology, pathogenesis and medical therapies involving these tissues, and great progress has been achieved in PSCs differentiation protocols. In this review, we will focus on the most common and/or advanced differentiation strategies currently used in generating endodermal lineage cells from PSCs. A brief discussion about the effect of early definitive endoderm differentiation on the final development products will follow.

Extracellular Matrix and Integrins in Embryonic Stem Cell Differentiation.

Embryonic stem cells (ESCs) are pluripotent cells with great therapeutic potentials. The in vitro differentiation of ESC was designed by recapitulating embryogenesis. Significant progress has been made to improve the in vitro differentiation protocols by toning soluble maintenance factors. However, more robust methods for lineage-specific differentiation and maturation are still under development. Considering the complexity of in vivo embryogenesis environment, extracellular matrix (ECM) cues should be considered besides growth factor cues. ECM proteins bind to cells and act as ligands of integrin receptors on cell surfaces. Here, we summarize the role of the ECM and integrins in the formation of three germ layer progenies. Various ECM-integrin interactions were found, facilitating differentiation toward definitive endoderm, hepatocyte-like cells, pancreatic beta cells, early mesodermal progenitors, cardiomyocytes, neuroectoderm lineages, and epidermal cells, such as keratinocytes and melanocytes. In the future, ECM combinations for the optimal ESC differentiation environment will require substantial study.

Improvement of Cell Survival During Human Pluripotent Stem Cell Definitive Endoderm Differentiation.

Definitive endoderm (DE) is a vital precursor for internal organs such as liver and pancreas. Efficient protocol to differentiate human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs) to DE is essential for regenerative medicine and for modeling diseases; yet, poor cell survival during DE differentiation remains unsolved. In this study, our use of B27 supplement in modified differentiation protocols has led to a substantial improvement. We used an SOX17-enhanced green fluorescent protein (eGFP) reporter hESC line to compare and modify established DE differentiation protocols. Both total live cell numbers and the percentages of eGFP-positive cells were used to assess differentiation efficiency. Among tested protocols, three modified protocols with serum-free B27 supplement were developed to generate a high number of DE cells. Massive cell death was avoided during DE differentiation and the percentage of DE cells remained high. When the resulting DE cells were further differentiated toward the pancreatic lineage, the expression of pancreatic-specific markers was significantly increased. Similar high DE differentiation efficiency was observed in H1 hESCs and iPSCs through the modified protocols. In B27 components, bovine serum albumin was found to facilitate DE differentiation and cell survival. Using our modified DE differentiation protocols, satisfactory quantities of quality DE can be produced as primary material for further endoderm lineage differentiation.

Secondary metabolites of plants from the genus chloranthus: chemistry and biological activities.

Chloranthus, a genus of the family Chloranthaceae, which is mainly distributed in eastern and southern Asia, has been used in Chinese folk medicine due to its antitumor, antifungal, and anti-inflammatory activities. This review compiles the research on isolation, structure elucidation, structural diversity, and bioactivities of Chloranthus secondary metabolites reported between 2007 and 2013. The metabolites listed encompass 82 sesquiterpenoids, 50 dimeric sesquiterpenoids, 15 diterpenoids, one coumarin, and five other compounds. Among them, dimeric sesquiterpenoids, the characteristic components of plants from the genus Chloranthus, have attracted considerable attention due to their complex structures and significant biological features, e.g., antitumor, antibacterial, antifungal, anti-inflammatory, and hepatoprotective activities, and potent and selective inhibition of the delayed rectifier (IK) K(+) current and tyrosinase.