DsbA-L ameliorates renal aging and renal fibrosis by maintaining mitochondrial homeostasis.

Renal fibrosis is the final pathological change in renal disease, and aging is closely related to renal fibrosis. Mitochondrial dysfunction has been reported to play an important role in aging, but the exact mechanism remains unclear. Disulfide-bond A oxidoreductase-like protein (DsbA-L) is mainly located in mitochondria and plays an important role in regulating mitochondrial function and endoplasmic reticulum (ER) stress. However, the role of DsbA-L in renal aging has not been reported. In this study, we showed a reduction in DsbA-L expression, the disruption of mitochondrial function and an increase in fibrosis in the kidneys of 12- and 24-month-old mice compared to young mice. Furthermore, the deterioration of mitochondrial dysfunction and fibrosis were observed in DsbA-L-/- mice with D-gal-induced accelerated aging. Transcriptome analysis revealed a decrease in Flt4 expression and inhibition of the PI3K-AKT signaling pathway in DsbA-L-/- mice compared to control mice. Accelerated renal aging could be alleviated by an AKT agonist (SC79) or a mitochondrial protector (MitoQ) in mice with D-gal-induced aging. In vitro, overexpression of DsbA-L in HK-2 cells restored the expression of Flt4, AKT pathway factors, SP1 and PGC-1α and alleviated mitochondrial damage and cell senescence. These beneficial effects were partially blocked by inhibiting Flt4. Finally, activating the AKT pathway or improving mitochondrial function with chemical reagents could alleviate cell senescence. Our results indicate that the DsbA-L/AKT/PGC-1α signaling pathway could be a therapeutic target for age-related renal fibrosis and is associated with mitochondrial dysfunction.

Comprehensive Bibliometric Analysis of Stem Cell Research in Alzheimer's Disease from 2004 to 2022.

INTRODUCTION: Stem cell-based regenerative medicine has provided an excellent opportunity to investigate therapeutic strategies and innovative treatments for Alzheimer's disease (AD). However, there is an absence of visual overviews to assess the published literature systematically. METHODS: In this review, the bibliometric approach was used to estimate the searched data on stem cell research in AD from 2004 to 2022, and we also utilized CiteSpace and VOSviewer software to evaluate the contributions and co-occurrence relationships of different countries/regions, institutes, journals, and authors as well as to discover research hot spots and encouraging future trends in this field. RESULTS: From 2004 to 2022, a total of 3,428 publications were retrieved. The number of publications and citations on stem cell research in AD has increased dramatically in the last nearly 20 years, especially since 2016. North America and Asia were the top 2 highest output regions. The leading country in terms of publications and access to collaborative networks was the USA. Centrality analysis revealed that the UCL (0.05) was at the core of the network. The Journal of Alzheimer's Disease (n = 102, 2.98%) was the most productive academic journal. The analyses of keyword burst detection indicated that exosomes, risk factors, and drug delivery only had burst recently. Citations and co-citation achievements clarified that cluster #0 induced pluripotent stem cells, #2 mesenchymal stem cells, #3 microglia, and #6 adult hippocampal neurogenesis persisted to recent time. CONCLUSION: This bibliometric analysis provides a comprehensive guide for clinicians and scholars working in this field. These analysis and results hope to provide useful information and references for future understanding of the challenges behind translating underlying stem cell biology into novel clinical therapeutic potential in AD.

Serum albumin and the risk of contrast-induced acute kidney injury after percutaneous coronary intervention.

Serum creatinine and serum albumin levels were measured prior to surgery, and serum creatinine level was also measured at 72 hours following percutaneous coronary intervention in 819 (January 1st, 2015 and December 31th, 2018). According to whether patients developed contrast-induced acute kidney injury or not, they were assigned to either a contrast-induced acute kidney injury group (72 cases, 8.8%) or a non-contrast-induced acute kidney injury group (747 cases; control). Serum albumin was significantly lower in the contrast-induced acute kidney injury group than control (39.33 ± 5.09 g/l and 42.69 ± 5.19 g/l, respectively, P < 0.001). The results of a receiver-operating curve analysis indicated a serum albumin level of 40.5 g/L was the optimal cut-off value for prediction of contrast-induced acute kidney injury and according to a multivariate logistic regression analysis, serum albumin was an independent biomarker for prediction of (95% confidence interval: 0.836-0.935, odds ratio: 0.884, P < 0.001). Serum albumin, a low-cost and easily assessable laboratory protein, was independently related to a greater risk of contrast-induced acute kidney injury among patients that received percutaneous coronary intervention. It is proposed that under these circumstances SA is a potential biomarker for contrast-induced acute kidney injury.

Guanxin Danshen Formulation improved the effect of mesenchymal stem cells transplantation for the treatment of myocardial infarction probably via enhancing the engraftment.

Although intravenous injection is the most convenient and feasible approach for mesenchymal stem cells (MSCs) delivery, the proportion of donor stem cells in the target myocardium after transplantation is small. It is believed that TCM enhances the effect of stem cell therapy by improving the hostile microenvironment and promoting the migration and survival of stem cells. Guanxin Danshen (GXDS) formulation is one of the main prescriptions for clinical treatment of ischemic heart diseases in China. The purpose of this study was to evaluate the effects of GXDS formulation administration combined with MSCs transplantation on cardiac function improvement, apoptosis, angiogenesis and survival of transplanted cells in an acute model of acute myocardial infarction (MI). After being labeled with GFP, MSCs were transplanted via intravenous injection. Meanwhile, GXDS dripping pills were given by intragastric administration for 4 weeks from 2 days before MI. Echocardiography showed moderate improvement in cardiac function after administration of GXDS formulation or intravenous transplantation of MSCs. However, GXDS formulation combined with MSCs transplantation significantly improved cardiac function after MI. The myocardial infarct size in rats treated with MSCs was similar to that in rats treated with GXDS formulation. However, GXDS formulation combined with MSCs transplantation significantly reduced infarction area. In addition, GXDS formulation combined with MSCs transplantation not only decreased cell apoptosis according to the TUNEL staining, but also enhanced angiogenesis in the peri-infarction and infarction area. Interestingly, the use of GXDS formulation increased the number of injected MSCs in the infarct area. Furthermore, GXDS formulation combined with MSCs transplantation increased SDF-1 levels in the infarcted area, but did not affect the expression of YAP. Our study provided a more feasible and accessible strategy to enhance the migration of stem cells after intravenous injection by oral administration of GXDS formulation. The combination of GXDS formulation and stem cell therapy has practical significance and application prospects in the treatment of ischemic cardiomyopathy such as MI.

Protective effect of breastfeeding against childhood leukemia in Zhejiang Province, P. R. China: a retrospective case-control study.

OBJECTIVES: Our research investigated the relationship between childhood leukemia and breastfeeding in the P. R. of China. METHODS: We conducted a retrospective case-control study from March 2008 to April 2017 at the Children's Hospital of Zhejiang University, Zhejiang province, P. R. of China, which reviewed 958 children who had been diagnosed with leukemia in case group and 785 healthy children in control group. Data were obtained from medical records, and if the medical records were incomplete, we called mothers of children by phone to complete the data. RESULTS: Breastfeeding reduces the risk of childhood leukemia; the effect is greater, if feeding continued for 7-9 months (p = 0.002). In addition, we suggest that some factors such as maternal age, smoking during pregnancy, abortion history, genetic factors, parents use of hair dye, and the history of using birth control pills before pregnancy can increase the risk of childhood leukemia. CONCLUSIONS: This study indicates that promoting breastfeeding for 7-9 months may help lower the childhood leukemia incidence. Our study firstly demonstrates that breastfeeding has protective effects against childhood leukemia in the P. R. of China. ABBREVIATIONS: ALL: Acute lymphocytic leukemia; AML: Acute myeloid leukemia.

Lycopene mitigates ß-amyloid induced inflammatory response and inhibits NF-κB signaling at the choroid plexus in early stages of Alzheimer's disease rats.

The choroid plexus is able to modulate the cognitive function, through changes in the neuroinflammatory response and in brain immune surveillance. However, whether lycopene is involved in inflammatory responses at the choroid plexus in the early stages of Alzheimer's disease, and its molecular underpinnings are elusive. In this rat study, lycopene was used to investigate its protective effects on inflammation caused by ß-amyloid. We characterized the learning and memory abilities, cytokine profiles of circulating TNF-α, IL-1ß and IL-6ß in the serum and the expressions of Toll like receptor 4 and nuclear factor-κB p65 mRNA and protein at the choroid plexus. The results showed that functional deficits of learning and memory in lycopene treatment groups were significantly improved compared to the control group without lycopene treatment in water maze test. The levels of serum TNF-α, IL-1ß and IL-6ß were significantly increased, and the expressions of TLR4 and NF-κB p65 mRNA and protein at the choroid plexus were up-regulated, indicating inflammation response was initiated following administration of Aß1-42. After intragastric pretreatment with lycopene, inflammatory cytokines were significantly reduced and lycopene also reversed the Aß1-42 induced up-regulation of TLR4 and NF-κB p65 mRNA and protein expressions at the choroid plexus. These results provided a novel evidence that lycopene significantly improved cognitive deficits and were accompanied by the attenuation of inflammatory injury via blocking the activation of NF-κB p65 and TLR4 expressions and production of cytokines, thereby endorsing its usefulness for diminishing ß-amyloid deposition in the hippocampus tissues.

Mesenchymal stem cell transplantation carried in SVVYGLR modified self-assembling peptide promoted cardiac repair and angiogenesis after myocardial infarction.

The efficiency of stem cell therapy for myocardial infarction (MI) was very low due to the hostile microenvironment and poor blood perfusion. In this study, we designed a new self-assembling peptide through adding angiogenic polypeptide SVVYGLR to the carboxyl terminal of RADA16, and evaluated the therapeutic potential of mesenchymal stem cell (MSC) transplantation carried in this designer self-assembling peptide (DSP) on MI. After the model of cell ischemia and hypoxia was established in vitro, cytoprotective effect of DSP on MSC was detected by AO/EB staining. MI was induced by ligating of the left anterior descending artery in female SD rats. MSC from male rats was labled by GFP with adenovirus transfection. MSC with DSP (MSC-DSP) or without DSP (MSC) were transplanted at the border of the infarcted area. The number of survival cell was more and necrotic cell was less in DSP group than that in control group after ischemia and hypoxia treatment in vitro. At 4 weeks after cell transplantation, compared with the MSC group, improvement of cardiac function was better, infarct size was reduced, collagen content and the number of apoptotic cells was decreased, and there were more GFP or SRY positive cells in MSC-DSP group. Moreover, the number of CD31 or α-smooth muscle actin positive blood vessels in MSC-DSP group was significantly higher than that in MSC group. DSP not only provided a microenvironment for the survival of MSC, but also promoted the angiogenesis after transplantation. This study provided novel strategy and experimental evidence for the clinical application of biomaterials in stem cell transplantation for treatment of ischemic heart disease such as MI.

Expression of hepcidin at the choroid plexus in normal aging rats is associated with IL-6/Stat3 signaling pathway.

Accumulating evidence has revealed that brain iron concentrations increase with aging, and the choroid plexus (CP) may be at the basis of iron-mediated toxicity and the increase in inflammation and oxidative stress that occurs with aging. The mechanism involves not only hepcidin, the key hormone in iron metabolism, but also iron-related proteins and signaling-transduction molecules, such as IL-6 and signal transducer and activator of transcription 3 (Stat3). The aim of the present study was to investigate the correlation between the IL-6/Stat3 signaling pathway and hepcidin at the CP in normal aging. Quantitative real time PCR and Western blot were used to determine the alterations in specific mRNA and corresponding protein changes at the CP at ages of 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33 and 36 months in Brown-Norway/Fischer (B-N/F) rats. The results demonstrated that hepcidin mRNA level at the CP kept stable in young rats (from 3 to 18 months), and increased with aging (from 21 to 36 months). The alterations of IL-6/p-Stat3 mRNA and protein expressions in normal aging were in accordance with that of hepcidin mRNA. Our data suggest that IL-6 may regulate hepcidin expression at the CP, upon interaction with the cognate cellular receptor, and through the Stat3 signaling transduction pathway.

Amyloid-beta transporter expression at the choroid plexus in normal aging: the possibility of reduced resistance to oxidative stress insults.

Accumulation of amyloid-beta peptides (Aß) results in amyloid burden in normal aging brain. Clearance of this peptide from the brain occurs via active transport at the interfaces separating the central nervous system (CNS) from the peripheral circulation. The present study was to investigate the change of Aß transporters expression at the choroid plexus (CP) in normal aging. Morphological modifications of CP were observed by transmission electron microscope. Real-time RT-PCR was used to measure mRNA expressions of Aß(42) and its transporters, which include low density lipoprotein receptor-related protein-1 and 2 (LRP-1 and -2), P-glycoprotein (P-gp) and the receptor for advanced glycation end-products (RAGE), at the CP epithelium in rats at ages of 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33 and 36 months. At the same time, the mRNA expressions of oxidative stress-related proteins were also measured. The results showed that a striking deterioration of the CP epithelial cells and increased Aß(42) mRNA expression were observed in aged rats, and there was a decrease in the transcription of the Aß efflux transporters, LRP-1 and P-gp, no change in RAGE mRNA expression and an increase in LRP-2, the CP epithelium Aß influx transporter. Heme oxygenase-1 (HO-1) and caspase-3 expressions at the CP epithelium increased with age at the mRNA level. These results suggest the efficacy of the CP in clearing of Aß deceases in normal aging, which results in the increase of brain Aß accumulation. And excess Aß interferes with oxidative phosphorylation, leads to oxidative stress and morphological structural changes. This in turn induces further pathological cascades of toxicity, inflammation and neurodegeneration process.

[Effects of repeated fasting/refeeding on lipid metabolism and uncoupling proteins expression in rats].

OBJECTIVE: To explore the expression changes of mRNA and protein of uncoupling protein 2 (UCP2) in adipose tissues and uncoupling protein 3 (UCP3) in muscle tissues of rats which were treated with repeated fasting/refeeding and followed by fed with high-fat diet, and their possible mechanism on lipid metabolism. METHODS: The model of repeating fasting/refeeding rats (repeated cycles of 1-day fasting and 1-day refeeding for 6 weeks fed with common-fat diet, RFR) was designed. At the end of the 6th week, the RFR rats were switched to high-fat diet every day (RFR-CF/HF). Moreover, the control rats were randomly divided into two groups and then fed with high-fat diet (HF) and common-fat diet (CF) respectively for 6 weeks. All rats were killed at the end of the 6th and the 12th week, serum and plasma samples were taken from abdominal aorta, and then the concentration of serum lipids, glucose, free fatty acid (FFA), and plasma insulin were measured. The histomorphological changes of liver tissues were observed by HE staining. The expression level of mRNA and protein of UCP2 in adipose tissues and UCP3 in muscle tissues was respectively measured by RT-PCR and Western blot. RESULTS: (1) The concentration of serum glucose in RFR group was significantly lower than that in control group (P < 0.05), while the concentration of serum FFA, expression level of UCP2 mRNA, UCP3 mRNA and protein were significantly higher than those in control group (P < 0.05). (2) The concentration of serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and plasma insulin in RFR-CF/HF group was significantly lower than that in HF group, but significantly higher than that in CF group (P < 0.05). The concentration of serum FFA was significantly lower than that of HF and CF groups (P < 0.01). The expression level in UCP2, UCP3 mRNA and protein was significantly higher than that of HF group, but significantly lower than that of CF group (P < 0.05). CONCLUSION: The feeding pattern of repeated fasting/refeeding can decrease the obese degree induced by high-fat diet, increase the mRNA and protein expression of UCP2 in adipose tissues and UCP3 in muscle tissues, up-regulate the proton leak caused by obesity, and improve the rate of basic energy metabolism in rats.

[Effect of lycopene on oxidative stress and behavioral deficits in rotenone induced model of Parkinson's disease].

OBJECTIVE: To investigate the neuroprotective potential of lycopene on oxidative stress and neurobehavioral abnormalities in rotenone induced Parkinson' disease (PD). METHODS: Forty adult C57BL/6 mice were randomly divided into four groups (n = 10): control, lycopene (10 mg/kg body weight, orally), rotenone (3 mg/kg bw, intraperitoneally) and rotenone plus lycopene, which were sacrificed for 5 weeks. The spectrophotometry was used to determine the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and the content of malondialdehyde (MDA) in substantia nigra and right striatum. At the same time, the number of tyrosine hydroxylase (TH), alpha-synuclein (alpha-SYN) and microtubule-associated protein 3 light chain (LC3-B) positive neurons were estimated by immunohistochemistry. We also examined neurobehavioral abnormalities by WT-200 water maze. RESULTS: Rotenone administration increased the MDA levels and significantly decreased the activities of SOD, GSH-Px and CAT. However, lycopene administration to the rotenone treated animals increased the activities of SOD, GSH-Px and CAT when compared to rotenone treated animals in substantia nigra and right striatum. The cognitive and motor deficits in rotenone administered animals, which were reversed on lycopene treatment. Along with this, the number of TH decreased, alpha-SYN increased and LC3-B positive neurons increased in rotenone administered animals, which were reversed on lycopene treatment. CONCLUSION: Collectively, these observations provide an evidence for beneficial effect of lycopene supplementation in rotenone-induced PD and suggest therapeutic potential in neurodegenerative diseases involving accentuated oxidative stress.

[Zinc supplementation effects on alcoholic liver disease and the molecular mechanism].

OBJECTIVE: To examine dietary zinc supplementation could alleviate the damage of alcoholic liver disease and the relationship with the expression of hepatocyte nuclear factor 4alpha (HNF-4alpha). METHODS: 40 adult C57 BL/6 mice were randomly divided into four groups (n = 10): control, zinc, ethanol and zinc plus ethanol, which were sacrificed after fed four different diets for 6 months. Zinc sulfate was added in the drinking water of the Zinc and Zinc Plus Ethanol group and the content was 75 mg/L. Liver regeneration was assessed by immunohistochemical staining of proliferating cell nuclear antigen (PCNA), and the expression of HNF-4alpha was determined by RT-PCR and Western blot. And as to assess the status of oxidative stress of the mice, malondialdehyde (MDA) and superoxide dismutase (SOD) were detected. RESULTS: Compared with the control group, the expression level of HNF-4alpha decreased significantly in the ethanol group (P < 0.05), and the content of MDA increased significantly in this group, while the content of SOD declined significantly (P < 0.05). Compared with the ethanol group, the number of PCNA-positive hepatocytes increased significantly, and the expression level of HNF-4alpha also increased in the zinc plus ethanol group (P < 0.05), and the content of SOD increased in this group, while MDA decreased significantly (P < 0.05). CONCLUSION: Long term ethanol exposure can lead to oxidoreduction imbalances which can be reversed by zinc supplementation. We suppose that zinc-enhanced liver regeneration is associated with an increase in HNF-4alpha, suggesting that dietary zinc supplementation may have beneficial effects in alcoholic liver disease.

[Effects of α-lipoic acid and vitamin C on oxidative stress in rat exposed to chronic arsenic toxicity].

OBJECTIVE: To explore arsenic-induced oxidative stress and the protective efficacy of α-lipoic acid and vitamin c. METHODS: 50 male SD rats were randomly divided into 5 groups. Ten rats (the control group) were exposed to deionized water for 6 weeks, and the others were alone exposed to sodium arsenite (50 mg/L water) for 6 weeks, at the same time, three group rats were administered intragastrically (i.g.) with α-lipoic acid 10 mg×kg(-1)×d(-1) and vitamin C 25 mg×kg(-1)×d(-1) either alone or in combination. At the end of experiment, blood was drawn from abdominal aorta, and then the blood, brain and liver of rats were used for biochemical assays, including blood glutathione (GSH), δ-aminolevulinic acid dehydratase (δ-ALAD ), reactive oxygen species (ROS) and oxidized glutathione (GSSG) level. At the same time, the super oxide dismutase (SOD) activity, glutathione peroxidase (GSH-Px) activity, catalase (CAT) activity, ATPase activity of brain and liver were determined. The caspase activity of brain were also determined. RESULTS: There were a significant increase in ROS level (P < 0.05), but a significant decrease in δ-ALAD activity (P < 0.01) in the chronic arsenic toxicity model group compared with the control group. These alterations were marginally restored by co-administration of vitamin C and α-lipoic acid individually, while significant recovery was observed in the animals supplemented with both the antioxidants together with arsenite in rat (P < 0.05). At the same time, there was a significant increase in the ROS and TBARS level of the brain and liver (P < 0.05), and caspase activity of the brain (P < 0.05), while there was a significant decrease in antioxidant enzymes and ATPase activity on arsenite exposure in rats (P < 0.05). These alterations were also marginally restored by co-administration of vitamin C and α-lipoic acid individually, while significant recovery was observed in the animals supplemented with both the antioxidants together with arsenite in rat (P < 0.05). CONCLUSIONS: Arsenite-induced oxidative stress can be significantly protected by co-administration of α-lipoic acid and vitamin C individually, but the best effects could be observed with combined administration of two antioxidants during arsenite exposure in animals. The dietary intervention of or supplementation with natural dietary nutrients is possible to prevent the effects of arsenic in populations of risk.

[Effects of genistein on contractility of isolated right ventricular muscles in guinea pig].

AIM: To study the effect of genistein (GEN) on contractility of isolated right ventricular muscles in guinea pig and its mechanisms. METHODS: Isolated guinea pig ventricular muscles were suspended in organ baths containing K-H solution.After an equilibration period, the effect of GEN on contraction of myocardium was observed. RESULTS: GEN and isoprenaline hydrochloride had the positive inotropic effects on contractity of myocardium. Meanwhile, the effect of GEN (1-100 micromol x L(-1)) was in dose-dependent manner. Propranolol (1 micromol x L(-1)) and verapamil hydrochloride (0.5 micromol x L(-1)) attenuated the positive inotropic effect of isoprenaline hydrochloride (1 micromol x L(-1)), but did not change the effect of GEN (50 micromol x L(-1)). Further more, the enhancement of the contraction induced by elevation of extracellular Ca2+ concentration in ventricular muscles had no change after pretreatment with GEN (1.10 micromol x L(-1)). In addition,the positive inotropic effect of GEN was inhibited partially by tamoxifen (1 micromol x L(-1)) and SQ22536 (1 micromol x L(-1)), also, could be attenuated by bpV (1 micromol x L(-1)). CONCLUSION: GEN has the positive inotropic effect on guinea pig ventricular muscles, which is not related to the activation of beta adrenoceptor, Ca2+ channel on cell membrane,but may involve in cAMP of intracellular signal transduction and tyrosine kinase pathway.

Electrocardiogram and heart rate in response to temperature acclimation in three representative vertebrates.

Comparisons of electrocardiogram (ECG) and heart rate characteristics of three representative species in response to temperature acclimation were studied. In toad (Bufo raddei), T wave had positive, negative and flat patterns, which was different from positive in lizard (Eremias multiocellata), blunt and broad in bird (Alectories magna). The duration of P-R interval, Q-T interval and QRS complex interval reduced with increasing temperature in toad, but the P-R and T-P intervals were affected mostly, the QRS and R-T intervals were relatively less affected in lizard. In the bird, the voltage of P, S and T wave scarcely changed, R wave increased slightly with temperature going up in the thermal neutral zone (20-35 degrees C), T and S waves tended to increase and P-S and S-T intervals shortened when temperature went below the neutral zone. Heart rate was high and relatively steady in bird, but changed linearly in relation to temperature in toad and lizard. The increasing of heart rate with temperature was mainly caused by the T-P interval shortened in lizard, but P-S and S-T intervals shortened in bird. Comparisons of ECG and heart rate characteristics of three representative species in response to temperature acclimation reflected phylogenetically based constraints on pacemaker rates, oxygen supply and modulatory mechanisms.