Low-temperature 3D-printed collagen/chitosan scaffolds loaded with exosomes derived from neural stem cells pretreated with insulin growth factor-1 enhance neural regeneration after traumatic brain injury

There are various clinical treatments for traumatic brain injury,including surgery,drug therapy,and rehabilitation therapy;howeve r,the therapeutic effects are limited.Scaffolds combined with exosomes represent a promising but challenging method for improving the repair of traumatic brain injury.In this study,we determined the ability of a novel 3D-printed collagen/chitosan scaffold loaded with exosomes derived from neural stem cells pretreated with insulin-like growth factor-1(3D-CC-INEXOS) to improve traumatic brain injury repair and functional recove ry after traumatic brain injury in rats.Composite scaffolds comprising collagen,chitosan,and exosomes derived from neural stem cells pretreated with insulin-like growth fa ctor-1(INEXOS) continuously released exosomes for 2weeks.Transplantation of 3D-CC-INExos scaffolds significantly improved motor and cognitive functions in a rat traumatic brain injury model,as assessed by the Morris water maze test and modified neurological seve rity scores.In addition,immunofluorescence staining and transmission electron microscopy showed that3D-CC-INExos implantation significantly improved the recove ry of damaged nerve tissue in the injured area.In conclusion,this study suggests that transplanted3D-CC-INExos scaffolds might provide a potential strategy for the treatment of traumatic brain injury and lay a solid foundation for clinical translation.

N-acetylserotonin alleviates retinal ischemia-reperfusion injury via HMGB1/RAGE/NF-κB pathway in rats

AIM:To observe the effects of N-acetylserotonin(NAS)administration on retinal ischemia-reperfusion(RIR)injury in rats and explore the underlying mechanisms involving the high mobility group box 1(HMGB1)/receptor for advanced glycation end-products(RAGE)/nuclear factor-kappa B(NF-κB)signaling pathway.METHODS:A rat model of RIR was developed by increasing the pressure of the anterior chamber of the eye.Eighty male Sprague Dawley were randomly divided into five groups:sham group(n=8),RIR group(n=28),RIR+NAS group(n=28),RIR+FPS-ZM1 group(n=8)and RIR+NAS+FPS-ZM1 group(n=8).The therapeutic effects of NAS were examined by hematoxylin-eosin(H&E)staining,and retinal ganglion cells(RGCs)counting.The expression of interleukin 1 beta(IL-1β),HMGB1,RAGE,and nod-like receptor 3(NLRP3)proteins and the phosphorylation of nuclear factorkappa B(p-NF-κB)were analyzed by immunohistochemistry staining and Western blot analysis.The expression of HMGB1 protein was also detected by enzyme-linked immunosorbent assay(ELISA).RESULTS:H&E staining results showed that NAS significantly reduced retinal edema and increased the number of RGCs in RIR rats.With NAS therapy,the HMGB1 and RAGE expression decreased significantly,and the activation of the NF-κB/NLRP3 pathway was antagonized along with the inhibition of p-NF-κB and NLRP3 protein expression.Additionally,NAS exhibited an anti-inflammatory effect by reducing IL-1βexpression.The inhibitory of RAGE binding to HMGB1 by RAGE inhibitor FPS-ZM1 led to a significant decrease of p-NF-κB and NLRP3 expression,so as to the IL-1βexpression and retinal edema,accompanied by an increase of RGCs in RIR rats.CONCLUSION:NAS may exhibit a neuroprotective effect against RIR via the HMGB1/RAGE/NF-κB signaling pathway,which may be a useful therapeutic target for retinal disease.

The Role for AVE0991 (MAS-Receptor Angiotensin II (1-7) Agonist) in Reducing Cisplatin-Induced Acute Kidney Injury on C57BL/6 Mice

Acute Kidney Injury (AKI) is a condition that causes nephrotoxicity in kidney tissues due to cisplatin-induced cancer treatments. Hence, it is proposed in this review that AVE0991 (a MAS-receptor Angiotensin II (1-7) agonist) may reduce cisplatin-induced acute kidney injury by promoting nitric oxide production.

Hypoxia inducible factor-1 alpha stabilization for regenerative therapy in traumatic brain injury

Mild traumatic brain injury（TBI）, also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neuroinflammation and nitroxidative burst, the chronic phase shows a lack of stimulation of the neurorepair process and regeneration. The deficiency of nitric oxide（NO）, the consequent disturbed NO metabolome, and imbalanced mechanisms of S-nitrosylation are implicated in blocking the mechanisms of neurorepair processes and functional recovery in the both phases. Hypoxia inducible factor-1 alpha（HIF-1α）, a master regulator of hypoxia/ischemia, stimulates the process of neurorepair and thus aids in functional recovery after brain trauma. The activity of HIF-1α is regulated by NO via the mechanism of S-nitrosylation of HIF-1α. S-nitrosylation is dynamically regulated by NO metabolites such as S-nitrosoglutathione（GSNO） and peroxynitrite. GSNO stabilizes, and peroxynitrite destabilizes HIF-1α. Exogenously administered GSNO was found not only to stabilize HIF-1α and to induce HIF-1α-dependent genes but also to stimulate the regeneration process and to aid in functional recovery in TBI animals.

Elevated levels of interleukin-1β, interleukin-6, tumor necrosis factor-α and vascular endothelial growth factor in patients with knee articular cartilage injury

BACKGROUND Inflammatory cytokines play a vital role in the occurrence of osteoarticular injury and inflammation. Whether inflammation-associated factors interleukin-1β(IL- 1β), IL-6, tumor necrosis factor-α(TNF-α) and vascular endothelial growth factor (VEGF) are involved in the pathogenesis of keen articular cartilage injury remains poorly understood. AIM To measure the levels of inflammatory factors [IL-1β, IL-6, TNF-α and VEGF] in patients with knee articular cartilage injury. METHODS Fifty-five patients with knee articular cartilage injury were selected as patient groups, who were divided into three grades [mild (n = 20), moderate (n = 19) and severe (n = 16)] according to disease severity and X-ray examinations. Meanwhile, 30 healthy individuals who underwent physical examination were selected as the control group. The levels of IL-1β, IL-6, TNF-α and VEGF were measured by ELISA and immunohistochemical staining. RESULTS Compared with the control group, patient groups displayed significantly higher levels of IL-1β, IL-6, TNF-α and VEGF, and the extent of increase was directly proportional to the severity of injury (P < 0.05). In addition, the number of cells with positive staining of IL-1β, IL-6, TNF-α and VEGF in the synovial membrane were significantly increased, along with increased disease severity (P < 0.05). After treatment, the scores of visual analogue scale and the Western Ontario and McMaster University of Orthopaedic Index in patient groups were 2.26 ± 1.13 and 15.56 ± 7.12 points, respectively, which were significantly lower than those before treatment (6.98 ± 1.32 and 49.48 ± 8.96). Correlation analysis suggested that IL-1β and TNF-α were positively correlated with VEGF. CONCLUSION IL-1β, IL-6, TNF-α and VEGF levels are increased in patients with knee articular cartilage injury, and are associated with the disease severity, indicating they might play an important role in the occurrence and development of knee articular cartilage injury. Furthermore, therapeutically targeting them might be a novel approach for the treatment of keen articular cartilage injury.

Prognostic Factors in Cardiorenal Syndrome Type 1: Retrospective Observational and Analytical Study

Introduction: Type 1 cardiorenal syndrome (CRS 1) is characterized by acute impairment of cardiac function leading to acute renal dysfunction. CRS1 is present in 25% of patients admitted for heart failure. The objective of our study is to analyze the epidemiological, clinical, therapeutic profile and the risk and prognostic factors of these patients. Materials and Methods: We identified 120 patients with cardiorenal syndrome (CRS) over a one-year period to determine the prevalence and risk factors for developing CRS 1. We analyzed the clinical, biological, and evolutionary profiles of patients with CRS 1 and determined the risk factors for the occurrence of acute kidney injury (AKI) as well as the mortality factors in these patients. Résultats: The average age of our patients with CRS1 is 58 ± 9 years, with a sex ratio of 1.4. The average eGFR of our patients is 35 ± 6.5 ml/min/1.73m2. Diabetes was found in 17% of our patients and hypertension in 14%. The etiology of cardiac impairment is predominantly acute coronary syndrome (ACS), followed by rhythm disorders. Renally, all our patients have acute kidney injury (AKI), with 86% having functional acute renal failure and 14% having acute tubular necrosis. Therapeutically, 50% of our patients are on diuretics, 42% receive beta-blocker treatment, and RAAS blockers are used in 29% of cases. Renal replacement therapy (RRT) sessions were required in 13.8% of cases. In univariate analysis, male gender, tachyarrhythmia, and hypertension are associated with the early onset of acute kidney injury (AKI). The use of diuretics, anemia, and low left ventricular ejection fraction (LVEF) are linked to a higher risk of developing CRS 1 (p = 0.021, p = 0.037, p = 0.010 respectively). In multivariate analysis, advanced age is significantly associated with increased mortality risk in CRS 1 patients (p = 0.030), while beta-blocker use is considered a protective factor (p = 0.014). Conclusion: Our study identifies several key factors associated with outcomes in type 1 CRS. Male gender, tachyarrhythmia, and hypertension are linked to early-onset AKI. The use of diuretics and the presence of anemia increase the risk of developing CRS1. Advanced age is significantly associated with higher mortality rates. Conversely, the use of beta-blockers appears to be protective in this patient population. .

Electroacupuncture-attenuated ischemic brain injury increases insulin-like growth factor-1 expression in a rat model of focal cerebral ischemia

Acupuncture has recently gained popularity in many countries as an alternative and complementary therapeutic intervention. Previous studies have shown that changes in genes, proteins, and their metabolites were measureable during acupuncture for treatment of cerebral ischemia. Through the use of in situ hybridization and immunohistochemistry, the present study confirmed that electroacupuncture increased insulin-like growth factor-1 mRNA and protein expression in the corpus stfiatum following cerebral ischemia, reduced brain edema following middle cerebral artery occlusion reperfusion, and decreased infarct volume. Results suggested that electroacupuncture is effective in the relief of cerebral ischemia by increasing endogenous insulin-like growth factor-1 expression.

Correlation between expression of two transforming growth factor-beta 1 receptors and microvascular density in a rat model of cerebral ischemia and reperfusion injury

The effects of transforming growth factor-β1 （TGF-β1） are currently controversial. Whether TGF-β1 promotes or inhibits revascularization under different conditions remains poorly understood. Based on previous studies, the current experiment established rat models of cerebral ischemia and reperfusion injury （IRI）, and demonstrated that pathological and functional damage was also increased after IRI. The most serious damage was observed at 3 days after reperfusion, at which time microvascular density fell to its lowest level. Soon afterwards, microvascular density increased, new collateral circulation was gradually established at 4 to 7 days after reperfusion, and pathological damage and neurological deficits were improved. TGF-β1, activin receptor-like kinase 5 （ALK5） mRNA and protein expression levels increased gradually over time. In contrast, ALK1 mRNA and protein expression decreased over the same period. A significant negative correlation was detected between microvascular density and expression of the ALK5 gene transcript. There was no correlation between microvascular density and ALK1 gene transcriptional expression following cerebral IRI in a rat model. These findings suggest that ALK5, rather than ALK1, is the critical receptor in the TGF-β1 signal pathways after cerebral IRI.

Hippocampal expression of apoptotic protease activating factor-1 following diffuse axonal injury under mild hypothermia

The influence of mild hypothermia on neural cell apoptosis remains poorly understood. Therefore, the present study established rat models of diffuse axonal injury （DAI） at 33℃. Morris water maze results demonstrated significantly better learning and memory functions in DAI rats with hypothermia compared with DAI rats with normothermia. Expression of apoptotic protease activating factor-1 in the hippocampal CA1 region was significantly lower in the DAI hypothermia group compared with the DAI normothermia group. Expression of apoptotic protease activating factor-1 positively correlated with latency, but negatively correlated with platform location times and time of swimming in the quadrant area. Results suggested that post-traumatic mild hypothermia in a rat model of DAI could provide cerebral protection by attenuating expression of apoptotic protease activating factor-1.

Mechanism of miR-214-mediated HIF1 α and KIM1 signaling pathway in rats with ischemic acute kidney injury

Objective:To investigate the mechanism of mir-214-mediated HIF1 alpha and KIM1 signaling pathways in rats with ischemic acute kidney injury. Methods:Rats were divided into three groups according to the difference of the preparation model, 16 in each group, sham operation group, IAKI group and miR-214 group.The rats in the latter two groups were established with ischemic acute kidney injury. After 48 hours, three groups of rats were treated with orbital venous blood. Urine was collected, biochemical parameters and KIM1 expression were detected. After using Masson's Trichrome, TUNEL, immunoblotting and PCR, renal histopathology, apoptosis of glomerular epithelial cells and expression of HIF1α, KIM1 protein and mRNA in renal tissues were detected. Results:The biochemical parameters of rats in the IAKI group included Scr, BUN and 24hUTP, which were higher than the previous group (P<0.05). The MIR-214 group was higher than the IAKI group. The sham operation group had intact renal tissue structure and good renal tubular and glomeruli. The IAKIgroup had increased glomerular interstitial, renal interstitial widening and inflammation. Severe infiltration, severe tubular atrophy, miR-214 group and IAKIgroup, renal interstitial inflammation increased, hardness increased, tubular atrophy more serious;black yellow is apoptotic cells, IAKIgroup rat renal tubular epithelial cell apoptosis The most serious, the degree of apoptosis was significantly higher than the sham operation group;the degree of apoptosis of renal tubular epithelial cells was increased in the miR-214 group compared with the IAKIgroup, and high levels of miR-214 could accelerate the apoptosis of epithelial cellsThe HIF1α and KIM1 proteins in the IAKI group were higher than those in the Previous group(P<0.05). The above indexes in the mir-214 group were better than those in the IAKI group(P<0.05). The HIF1α and KIM1 mRNA in the IAKI group were higher than in the sham operation group, and the above indicators in the mir-214 group(P<0.05). Better than the IAKI group(P<0.05);Conclusions:The increase of miR-214 accelerates the apoptosis of glomerular epithelial cells, impaired renal tissue damage, and mediates the elevation of HIF1α and KIM1, further aggravating the condition of IAKI rats.

Urinary Kidney Injury Molocule-1 Level in Preterm Neonates with Respiratory Distress Syndrome

Background: Despite recent advances in perinatal and neonatal care in respiratory distress syndrome (RDS) prevention and treatment, a considerable number of these neonates suffer from acute kidney injury (AKI), and it is associated with poor outcome as an independent risk factor. KIM-1 mRNA and protein are expressed at a low level in normal kidney but are increased in post ischemic kidney. Aim: The aim is to detect the value of urinary KIM-1 measurement as an early predictor marker of acute kidney injury in preterm neonates with respiratory distress syndrome. Patients and methods: The study included 30 preterm newborn with (RDS) ≤36 weeks during the period from October 2014 to March 2015. Also the study included 30 apparently healthy newborn ≤36 weeks as controls. They were selected from NICU of Manshiate Elbakry hospital Cairo, Egypt. uKIM-1 along with serum creatinine levels and eGFR were assessed in days 1 of life for both groups and in day 3 for cases. Results: In day one of life, we found a significant increase in uKIM-1 levels in preterm newborn with RDS compared to their controls (2.88 ± 1.01 ng/ml and 0.95 ± 0.52 ng/ml respectively (p = 0.001)). There is no significant difference between both groups regarding serum creatinine and eGFR. In day 3 of life, preterm with RDS had significant decrease in uKIM-1 levels compared to day 1 of life with significant increase in non-survivor compared to survivor group ( 2.30 ± 1.56 ng/ml and 1.30 ± 0.90 ng/ml respectively (p = 0.03)). The sensitivity and specificity of uKIM-1 and serum creatinine was calculated (100.00%, 86.67% and 33.33%;95.00%) respectively. Conclusion: Preterm neonate with RDS is at high risk of developing AKI. Early and serial uKIM-1 measurements can be used as a non-invasive indicator of kidney injury in premature newborn with RDS.

Ginsenoside Rg1 and Resveratrol Alleviate Acute Kidney Injury Induced by Cisplatin via Downregulation of Autophagy in Mice

Background: Cisplatin, a chemotherapeutic agent, is widely used in the treatment of malignant tumors. Nephrotoxicity, especially acute kidney injury (AKI), is the most common and severe adverse reaction of cisplatin. Resveratrol and ginsenoside Rg1, two natural products, have been found to have renal protective effects. However, the effects and the mechanisms in cisplatin-induced AKI need further investigation. Methods: The mouse models of cisplatin-induced AKI and several treatment groups were established. Male C57BL/6 mice were divided into five groups: saline control group, cisplatin injury group, resveratrol treatment group, Rg1 treatment group, resveratrol and Rg1 combined treatment group. Serological analysis of serum urea nitrogen was aimed to reflect the function of kidney, and histological analysis of renal tissue sections was aimed to assess the damage of proximal convoluted tubules. The expression levels of autophagy-related proteins Beclin 1 and LC3 were detected by western blotting and qRT-PCR respectively. Results: The renal function was improved and renal damage was alleviated in Rg1 and resveratrol alone or combined treatment groups compared with the cisplatin injury group. For the mechanism, treatment with Rg1 and resveratrol alone or in combination decreased the expressions of Beclin 1 both at protein and mRNA levels, decreased LC3II/I protein levels, indicating that autophagy was inhibited by treatment with Rg1 and resveratrol alone or in combination. Conclusion: Resveratrol and Rg1 alleviated the kidney damage caused by cisplatin, and reduced autophagy was involved in the renoprotective effects of resveratrol and Rg1 against cisplatin-induced AKI. This study may provide new evidence to alleviate cisplatin-induced AKI.

CD36 promotes tubular ferroptosis by regulating the ubiquitination of FSP1 in acute kidney injury

Reactive oxidative species(ROos)production-driven ferroptosis plays a role in acute kidney injury(Akl).However,its exact molecular mechanism is poorly understood.Scavenger receptor CD36 has important roles in oxidizing lipids,lipid accumulation,metabolic syndrome,and insulin resistance in chronic kidney disease,but its roles remain unexplored in AKl.The present study investigated the role and mechanism of CD36 in regulating proximal tubular cell ferroptosis and AKl.The expression of CD36 was found to be significantly up-regulated in AKI renal tissues and correlated with renal function,which might serve as an independent biomarker for AKl patients.Moreover,in adult mice subjected to AKl,deletion of CD36(CD36-/-)induced tubular cell Ros accumulation,ferroptosis activation,and renal injury.Mechanistically,combining LC-MS/MS,co-IP,and ubiquitination analyses revealed that CD36 could specifically bind to ferroptosis suppressor protein 1(FSP1)and regulate its ubiquitination at sites K16 and K24,leading to FSP1 degradation and progression of ferroptosis in AKl.The present results emphasize a novel mechanism of CD36 in cisplatin-induced AKl.The discovery of the special CD36 roles in promoting ferroptosis and AKI development by regulating the ubiquitination of FSP1 in proximal tubular cells may be potential therapeutic targets for AKl.Moreover,CD36 may play a key role in the progression of AKl.Therefore,targeting CD36 may provide a promising treatment option for AKI.

Bone-marrow mesenchymal stem cells reduce rat intestinal ischemia-reperfusion injury, ZO-1 downregulation and tight junction disruption via a TNF-α-regulated mechanism

AIM: To investigate the effect of bone-marrow mesenchymal stem cells (BM MSCs) on the intestinal mucosa barrier in ischemia/reperfusion (I/R) injury. METHODS: BM MSCs were isolated from male Sprague-Dawley rats by density gradient centrifugation, cultured, and analyzed by flow cytometry. I/R injury was induced by occlusion of the superior mesenteric artery for 30 min. Rats were treated with saline, BM MSCs (via intramucosal injection) or tumor necrosis factor (TNF)-α blocking antibodies (via the tail vein). I/R injury was assessed using transmission electron microscopy, hematoxylin and eosin (HE) staining, immunohistochemistry, western blotting and enzyme linked immunosorbent assay.RESULTS: Intestinal permeability increased, tight junctions (TJs) were disrupted, and zona occludens 1 (ZO-1) was downregulated after I/R injury. BM MSCs reduced intestinal mucosal barrier destruction, ZO-1 downregulation, and TJ disruption. The morphological abnormalities after intestinal I/R injury positively correlated with serum TNF-α levels. Administration of anti-TNF-α IgG or anti-TNF-α receptor 1 antibodies attenuated the intestinal ultrastructural changes, ZO-1 downregulation, and TJ disruption. CONCLUSION: Altered serum TNF-α levels play an important role in the ability of BM MSCs to protect against intestinal I/R injury.

Insulin like growth factor-1 increases fatty liver preservation in IGL-1 solution

AIM: To investigate the benefits of insulin like growth factor-1 (IGF-1) supplementation to serum-free institut georges lopez-1 (IGL-1) solution to protect fatty liver against cold ischemia reperfusion injury. METHODS: Steatotic livers were preserved for 24 h in IGL-1  solution supplemented with or without IGF-1 and then perfused "ex vivo " for 2 h at 37℃. We examined the effects of IGF-1 on hepatic damage and function (transaminases, percentage of sulfobromophthalein clearance in bile and vascular resistance). We also studied other factors associated with the poor tolerance of fatty livers to cold ischemia reperfusion injury such as mitochondrial damage, oxidative stress, nitric oxide, tumor necrosis factor-α (TNF-α) and mitogen-activated protein kinases.RESULTS: Steatotic livers preserved in IGL-1 solutionsupplemented with IGF-1 showed lower transaminase levels, increased bile clearance and a reduction in vascular resistance when compared to those preserved in IGL-1solution alone. These benefits are mediated by activation of AKT and constitutive endothelial nitric oxide synthase (eNOS), as well as the inhibition of inflammatory cytokines such as TNF-α. Mitochondrial damage and oxidative stress were also prevented.CONCLUSION: IGL-1  enrichment with IGF-1 increasedfatty liver graft preservation through AKT and eNOS activation, and prevented TNF-α release during normothermic reperfusion.

TLR4-HMGB1-, MyD88- and TRIF-dependent signaling in mouse intestinal ischemia/reperfusion injury

AIM: To characterize high-mobility group protein 1-toll-like receptor 4(HMGB1-TLR4) and downstream signaling pathways in intestinal ischemia/reperfusion(I/R) injury.METHODS: Forty specific-pathogen-free male C57BL/6 mice were randomly divided into five groups(n = 8 per group): sham, control, anti-HMGB1, anti-myeloid differentiation gene 88(My D88), and anti-translocatingchain-associating membrane protein(TRIF) antibody groups. Vehicle with the control Ig G antibody, antiHMGB1, anti-My D88, or anti-TRIF antibodies(all 1 mg/kg, 0.025%) were injected via the caudal vein 30 min prior to ischemia. After anesthetization, the abdominal wall was opened and the superior mesenteric artery was exposed, followed by 60 min mesenteric ischemia and then 60 min reperfusion. For the sham group, the abdominal wall was opened for 120 min without I/R. Levels of serum nuclear factor(NF)-κB p65, interleukin(IL)-6, and tumor necrosis factor(TNF)-α were measured, along with myeloperoxidase activity in the lung and liver. Inaddition,morphologic changes that occurred in the lung and intestinal tissues were evaluated. Levels of m RNA transcripts encoding HMGB1 and NF-κB were measured by real-time quantitative PCR, and levels of HMGB1 and NF-κB protein were measured by Western blot. Results were analyzed using one-way analysis of variance.RESULTS: Blocking HMGB 1, MyD 8 8, and TRIF expression by injecting anti-HMGB1, anti-My D88, or anti-TRIF antibodies prior to ischemia reduced the levels of inflammatory cytokines in serum; NF-κB p65: 104.64 ± 11.89, 228.53 ± 24.85, 145.00 ± 33.63, 191.12 ± 13.22, and 183.73 ± 10.81(P < 0.05); IL-6: 50.02 ± 6.33, 104.91 ± 31.18, 62.28 ± 6.73, 85.90 ± 17.37, and 78.14 ± 7.38(P < 0.05); TNF-α, 43.79 ± 4.18, 70.81 ± 6.97, 52.76 ± 5.71, 63.19 ± 5.47, and 59.70 ± 4.63(P < 0.05) for the sham, control, anti-HMGB1, anti-My D88, and anti-TRIF groups, respectively(all in pg/m L).Antibodies also alleviated tissue injury in the lung and small intestine compared with the control group in the mouse intestinal I/R model. The administration of antiHMGB1, anti-My D88, and anti-TRIF antibodies markedly reduced damage caused by I/R, for which anti-HMGB1 antibody had the most obvious effect.CONCLUSION: HMGB1 and its downstream signaling pathway play important roles in the mouse intestinal I/R injury, and the effect of the TRIF-dependent pathway is slightly greater.

M1-type microglia can induce astrocytes to deposit chondroitin sulfate proteoglycan after spinal cord injury

After spinal cord injury(SCI),astrocytes gradually migrate to and surround the lesion,depositing chondroitin sulfate proteoglycan-rich extracellular matrix and forming astrocytic scar,which limits the spread of inflammation but hinders axon regeneration.Meanwhile,microglia gradually accumulate at the lesion border to form microglial scar and can polarize to generate a pro-inflammatory M1 phenotype or an anti-inflammatory M2 phenotype.However,the effect of microglia polarization on astrocytes is unclear.Here,we found that both microglia(CX3 CR1^(+))and astrocytes(GFAP^(+))gathered at the lesion border at 14 days post-injury(dpi).The microglia accumulated along the inner border of and in direct contact with the astrocytes.M1-type microglia(i NOS^(+)CX3 CR1^(+))were primarily observed at 3 and 7 dpi,while M2-type microglia(Arg1^(+)CX3 CR1^(+))were present at larger numbers at 7 and 14 dpi.Transforming growth factor-β1(TGFβ1)was highly expressed in M1 microglia in vitro,consistent with strong expression of TGFβ1 by microglia in vivo at 3 and 7 dpi,when they primarily exhibited an M1 phenotype.Furthermore,conditioned media from M1-type microglia induced astrocytes to secrete chondroitin sulfate proteoglycan in vitro.This effect was eliminated by knocking down sex-determining region Y-box 9(SOX9)in astrocytes and could not be reversed by treatment with TGFβ1.Taken together,our results suggest that microglia undergo M1 polarization and express high levels of TGFβ1 at 3 and 7 dpi,and that M1-type microglia induce astrocytes to deposit chondroitin sulfate proteoglycan via the TGFβ1/SOX9 pathway.The study was approved by the Institutional Animal Care and Use Committee of Anhui Medical University,China(approval No.LLSC20160052)on March 1,2016.

Neutrophil gelatinase-associated lipocalin does not predict acute kidney injury in heart failure

BACKGROUND Acute cardiorenal syndrome type 1(CRS-1)is defined by a rapid cardiac dysfunction leading to acute kidney injury(AKI).Neutrophil gelatinaseassociated lipocalin(NGAL)is expressed on the surface of human neutrophils and epithelial cells,such as renal tubule cells,and its serum(sNGAL)and urinary have been used to predict AKI in different clinical settings.AIM To characterize CRS-1 in a cohort of patients with acute heart diseases,evaluating the potentiality of sNGAL as an early marker of CRS-1.METHODS We performed a retrospective cohort,multi-centre study.From January 2010 to December 2011,we recruited 202 adult patients admitted to the coronary intensive care unit(CICU)with a diagnosis of acute heart failure or acute coronary syndrome.We monitored the renal function to evaluate CRS-1 development and measured sNGAL levels within 24 h and after 72 h of CICU admission.RESULTS Overall,enrolled patients were hemodynamically stable with a mean arterial pressure of 92(82-107)mmHg,55/202(27.2%)of the patients developed CRS-1,but none of them required dialysis.Neither the NGAL delta value(AUC 0.40,95%CI:0.25-0.55)nor the NGAL peak(AUC 0.45,95%CI:0.36-0.54)or NGAL cutoff(≥140 ng/mL)values were statistically significant between the two groups(CRS-1 vs no-CRS1 patients).The area under the ROC curve for the prediction of CRS-1 was 0.40(95%CI:0.25-0.55)for the delta NGAL value and 0.45(95%CI:0.36-0.54)for the NGAL peak value.Finally,in multivariate analysis,the risk of developing CRS-1 was correlated with age>60 years,urea nitrogen at admission and 24 h-urine output(AUC 0.83,SE=60.5%SP=93%),while sNGAL was not significantly correlated.CONCLUSION In our population,sNGAL does not predict CRS-1,probably as a consequence of the mild renal injury and the low severity of heart disease.So,these data might suggest that patient selection should be taken into account when considering the utility of NGAL measurement as a biomarker of kidney damage.

Urine microscopy and neutrophilelymphocyte ratio are early predictors of acute kidney injury in patients with urinary tract infection

Objective:Urinary tract infection(UTI)is a common cause of morbidity and hospitalisation in the population worldwide.Upper UTI is indolent and causes subclinical acute kidney injury(AKI)resulting in preventable cause of scarring of renal parenchyma.We explored urinary and serum levels of kidney injury molecule-1(KIM-1),haematological parameters and quantitative urine microscopy parameters to predict kidney injury.Methods:Neutrophilelymphocyte ratio(NLR)is obtained by dividing absolute neutrophil count with absolute lymphocyte count.Quantitative urine sediment microscopy was performed and correlated with clinical,biochemical and haematological findings to predict AKI in patients with UTI.Quantitative ELISA was performed for serum and urine levels of KIM-1.Seventy two adult patients with UTI were enrolled,45 of whom had AKI while 27 were in the non-AKI group.Results:NLR(p=0.005)and renal tubular epithelial cell-granular cast score in quantitative urine microscopy(p=0.008)are strong predictors of AKI in patients with UTI while rest of quantitative urine microscopy parameters and serum and urinary levels of KIM-1 molecule were not found to be useful in prediction of AKI.Conclusion:NLR in haemogram is a novel and useful biomarker for predicting AKI in patients with UTI.

Local inhibition of matrix metalloproteinases reduced M2 macrophage activity and impeded recovery in spinal cord transected rats after treatment with fibroblast growth factor-1 and nerve grafts

Alternatively activated macrophages （M2 macrophages） promote central nervous system regeneration. Our previous study demonstrated that treatment with peripheral nerve grafts and fibroblast growth factor-1 recruited more M2 macrophages and improved partial functional recovery in spinal cord transected rats. The migration of macrophages is matrix metalloproteinase （MMP） dependent. We used a general inhibitor of MMPs to influence macrophage migration, and we examined the migration of macrophage populations and changes in spinal function. Rat spinal cords were completely transected at Ts, and 5 mm of spinal cord was removed （group T）. In group R, spinal cord-transected rats received treatment with fibroblast grow th factor- 1 and peripheral nerve grafts. In group RG, rats received the same treatment as group R with the addition of 200 μM GM6001 （an MMP inhibitor） to the fibrin mix. We found that MMP-9, but not MMP- 2, was upregulated in the graft area of rats in group R. Local application of the MMP inhibitor resulted in a reduction in the ratio of arginase-1 （M2 macrophage subset）/inducible nitric oxide synthase-postive cells. When the MMP inhibitor was applied at 8 weeks postoperation, the partial functional recovery observed in group R was lost. This effect was accompanied by a decrease in brain-derived neurotrophic factor levels in the nerve graft. These results suggested that the arginase-1 positive population in spinal cord transected rats is a migratory cell population rather than the phenotypic conversion of early iNOS^＋ cells and that the migration of the arginase-1^＋ population could be regulated locally. Simultaneous application of MMP in- hibitors or promotion of MMP activity for spinal cord injury needs to be considered if the coadministered treatment involves M2 recruitment.