A dietary commensal microbe enhances antitumor immunity by activating tumor macrophages to sequester iron.

Innate immune cells generate a multifaceted antitumor immune response, including the conservation of essential nutrients such as iron. These cells can be modulated by commensal bacteria; however, identifying and understanding how this occurs is a challenge. Here we show that the food commensal Lactiplantibacillus plantarum IMB19 augments antitumor immunity in syngeneic and xenograft mouse tumor models. Its capsular heteropolysaccharide is the major effector molecule, functioning as a ligand for TLR2. In a two-pronged manner, it skews tumor-associated macrophages to a classically active phenotype, leading to generation of a sustained CD8+ T cell response, and triggers macrophage 'nutritional immunity' to deploy the high-affinity iron transporter lipocalin-2 for capturing and sequestering iron in the tumor microenvironment. This process induces a cycle of tumor cell death, epitope expansion and subsequent tumor clearance. Together these data indicate that food commensals might be identified and developed into 'oncobiotics' for a multi-layered approach to cancer therapy.

Human autoinflammatory disease reveals ELF4 as a transcriptional regulator of inflammation.

Transcription factors specialized to limit the destructive potential of inflammatory immune cells remain ill-defined. We discovered loss-of-function variants in the X-linked ETS transcription factor gene ELF4 in multiple unrelated male patients with early onset mucosal autoinflammation and inflammatory bowel disease (IBD) characteristics, including fevers and ulcers that responded to interleukin-1 (IL-1), tumor necrosis factor or IL-12p40 blockade. Using cells from patients and newly generated mouse models, we uncovered ELF4-mutant macrophages having hyperinflammatory responses to a range of innate stimuli. In mouse macrophages, Elf4 both sustained the expression of anti-inflammatory genes, such as Il1rn, and limited the upregulation of inflammation amplifiers, including S100A8, Lcn2, Trem1 and neutrophil chemoattractants. Blockade of Trem1 reversed inflammation and intestine pathology after in vivo lipopolysaccharide challenge in mice carrying patient-derived variants in Elf4. Thus, ELF4 restrains inflammation and protects against mucosal disease, a discovery with broad translational relevance for human inflammatory disorders such as IBD.

Lipocalin-2: a novel potential therapy for GVHD.

Czech et al. used mouse models of allogeneic hematopoietic stem cell transplantation (allo-HCT) to investigate the role of lipocalin-2 (LCN2) as a newfound regulator of intestinal graft-versus-host disease (GVHD). Administration of recombinant LCN2 protein after disease onset prevented GVHD progression, suggesting that it may play a role in reversing tissue damage that has already begun.

Aberrant activation of hippocampal astrocytes causes neuroinflammation and cognitive decline in mice.

Reactive astrocytes are associated with neuroinflammation and cognitive decline in diverse neuropathologies; however, the underlying mechanisms are unclear. We used optogenetic and chemogenetic tools to identify the crucial roles of the hippocampal CA1 astrocytes in cognitive decline. Our results showed that repeated optogenetic stimulation of the hippocampal CA1 astrocytes induced cognitive impairment in mice and decreased synaptic long-term potentiation (LTP), which was accompanied by the appearance of inflammatory astrocytes. Mechanistic studies conducted using knockout animal models and hippocampal neuronal cultures showed that lipocalin-2 (LCN2), derived from reactive astrocytes, mediated neuroinflammation and induced cognitive impairment by decreasing the LTP through the reduction of neuronal NMDA receptors. Sustained chemogenetic stimulation of hippocampal astrocytes provided similar results. Conversely, these phenomena were attenuated by a metabolic inhibitor of astrocytes. Fiber photometry using GCaMP revealed a high level of hippocampal astrocyte activation in the neuroinflammation model. Our findings suggest that reactive astrocytes in the hippocampus are sufficient and required to induce cognitive decline through LCN2 release and synaptic modulation. This abnormal glial-neuron interaction may contribute to the pathogenesis of cognitive disturbances in neuroinflammation-associated brain conditions.

C/EBPδ Mediates Immunity to Renal Autoinflammatory Disorders in a Stage-specific Manner.

Kidney disease represents a major medical and economic burden for which improved treatments are urgently needed. Emerging data have implicated Th17 cells and IL-17 signaling in the underlying pathogenesis of autoantibody-induced glomerulonephritis (AGN). However, the downstream transduction pathways mediated by IL-17 in autoimmunity are not well defined. In this article, we show that CCAAT/enhancer-binding protein (C/EBP) δ is elevated in kidney biopsies from multiple manifestations of human AGN. C/EBPδ is similarly upregulated in a mouse model of anti-glomerular basement membrane protein-mediated kidney disease, and Cebpd-/- mice were fully refractory to disease. Although C/EBPδ is expressed in a variety of cell types, C/EBPδ was required only in the radioresistant compartment to drive GN pathology. C/EBPδ induced expression of several IL-17-induced kidney injury markers and cytokines implicated in disease, including Il6 and Lcn2. Because mouse AGN models do not progress to fibrosis, we employed a nephrotoxic injury model using aristolochic acid I to assess the contribution of the IL-17-C/EBPδ pathway to renal fibrotic events. Surprisingly, deficiency of either C/EBPδ or the IL-17 receptor caused kidney fibrosis to be enhanced. Thus, C/EBPδ and IL-17 play divergent and apparently stage-specific roles in the pathogenesis of kidney disease.

Quantitative Proteomics of Tissue-Infiltrating T Cells From CRC Patients Identified Lipocalin-2 Induces T-Cell Apoptosis and Promotes Tumor Cell Proliferation by Iron Efflux.

T cells play the most pivotal roles in antitumor immunity; the T-cell proteome and the differentially expressed proteins in the tumor immune microenvironment have rarely been identified directly from the clinical samples, especially for tumors that lack effective immunotherapy targets, such as colorectal cancer (CRC). In this study, we analyzed the protein expression pattern of the infiltrating T cells isolated from CRC patients using quantitative proteomics. CD4+ and CD8+ T cells were isolated from clinical samples and labeled by tandem mass tag reagents, and the differentially expressed proteins were quantified by mass spectrometry. The T-cell proteome profiling revealed dysfunctions in these tumor-infiltrating T cells. Specifically, antitumor immunity was suppressed because of differentially expressed metal ion transporters and immunity regulators. For the first time, lipocalin-2 (LCN2) was shown to be significantly upregulated in CD4+ T cells. Quantitative proteomic analysis of LCN2-overexpressed Jurkat cells showed that LCN2 damaged T cells by changes in iron transport. LCN2 induced T-cell apoptosis by reducing cellular iron concentration; moreover, the iron that was transported to the tumor microenvironment aided tumor cell proliferation, promoting tumor development. Meanwhile, LCN2 also influenced tumor progression through immune cytokines and cholesterol metabolism. Our results demonstrated that LCN2 has immunosuppressive functions that can promote tumor development; therefore, it is a potential immunotherapy target for CRC.

Escape from breast tumor dormancy: The convergence of obesity and menopause.

Obesity is associated with an increased risk of, and a poor prognosis for, postmenopausal (PM) breast cancer (BC). Our goal was to determine whether diet-induced obesity (DIO) promotes 1) shorter tumor latency, 2) an escape from tumor dormancy, and 3) an acceleration of tumor growth and to elucidate the underlying mechanism(s). We have developed in vitro assays and PM breast tumor models complemented by a noninvasive imaging system to detect vascular invasion of dormant tumors and have used them to determine whether obesity promotes the escape from breast tumor dormancy and tumor growth by facilitating the switch to the vascular phenotype (SVP) in PM BC. Obese mice had significantly higher tumor frequency, higher tumor volume, and lower overall survival compared with lean mice. We demonstrate that DIO exacerbates mammary gland hyperplasia and neoplasia, reduces tumor latency, and increases tumor frequency via an earlier acquisition of the SVP. DIO establishes a local and systemic proangiogenic and inflammatory environment via the up-regulation of lipocalin-2 (LCN2), vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) that may promote the escape from tumor dormancy and tumor progression. In addition, we show that targeting neovascularization via a multitargeted receptor tyrosine kinase inhibitor, sunitinib, can delay the acquisition of the SVP, thereby prolonging tumor latency, reducing tumor frequency, and increasing tumor-free survival, suggesting that targeting neovascularization may be a potential therapeutic strategy in obesity-associated PM BC progression. This study establishes the link between obesity and PM BC and, for the first time to our knowledge, bridges the dysfunctional neovascularization of obesity with the earliest stages of tumor development.

Repurposing AZD5438 and Dabrafenib for Cisplatin-Induced AKI.

SIGNIFICANCE STATEMENT: To combat both untoward effects of nephrotoxicity and ototoxicity in cisplatin-treated patients, two potential therapeutic oral anticancer drugs AZD5438 and dabrafenib, a phase-2 clinical trial protein kinase CDK2 inhibitor and an US Food and Drug Administration-approved drug BRAF inhibitor, respectively, were tested in an established mouse AKI model. Both drugs have previously been shown to protect significantly against cisplatin-induced hearing loss in mice. Each drug ameliorated cisplatin-induced increases in the serum biomarkers BUN, creatinine, and neutrophil gelatinase-associated lipocalin. Drugs also improved renal histopathology and inflammation, mitigated cell death by pyroptosis and necroptosis, and significantly enhanced overall survival of cisplatin-treated mice. BACKGROUND: Cisplatin is an effective chemotherapy agent for a wide variety of solid tumors, but its use is dose-limited by serious side effects, including AKI and hearing loss. There are no US Food and Drug Administration-approved drugs to treat both side effects. Recently, two anticancer oral drugs, AZD5438 and dabrafenib, were identified as protective against cisplatin-induced hearing loss in mice. We hypothesize that similar cell stress and death pathways are activated in kidney and inner ear cells when exposed to cisplatin and tested whether these drugs alleviate cisplatin-induced AKI. METHODS: The HK-2 cell line and adult FVB mice were used to measure the protection from cisplatin-induced cell death and AKI by these drugs. Serum markers of kidney injury, BUN, creatinine, and neutrophil gelatinase-associated lipocalin as well as histology of kidneys were analyzed. The levels of markers of kidney cell death, including necroptosis and pyroptosis, pERK, and proliferating cell nuclear antigen, were also examined by Western blotting and immunofluorescence. In addition, CDK2 knockout (KO) mice were used to confirm AZD5438 protective effect is through CDK2 inhibition. RESULTS: The drugs reduced cisplatin-induced cell death in the HK-2 cell line and attenuated cisplatin-induced AKI in mice. The drugs reduced serum kidney injury markers, inhibited cell death, and reduced the levels of pERK and proliferating cell nuclear antigen, all of which correlated with prolonged animal survival. CDK2 KO mice were resistant to cisplatin-induced AKI, and AZD5438 conferred no additional protection in the KO mice. CONCLUSIONS: Cisplatin-induced damage to the inner ear and kidneys shares similar cellular beneficial responses to AZD5438 and dabrafenib, highlighting the potential therapeutic use of these agents to treat both cisplatin-mediated kidney damage and hearing loss.

Neutrophil-Associated Proteins as Novel Biomarkers Elevated in Cerebrospinal Fluid of Patients With Neurosyphilis.

BACKGROUND: The immunopathological mechanisms underlying neurosyphilis remain incompletely elucidated, and the diagnosis of neurosyphilis presents challenges. METHODS: We used an antibody microarray to detect 640 proteins in cerebrospinal fluid (CSF) samples collected from 6 patients with non-neurosyphilis and 10 with neurosyphilis. The levels of CSF CXCL1, CXCL8, G-CSF, LCN2, MMP8, and MMP9 in 46 patients with non-neurosyphilis, 51 with untreated neurosyphilis, and 31 posttreatment for neurosyphilis were quantified using enzyme-linked immunosorbent assay. The associations between the levels of these proteins and clinical parameters in neurosyphilis were evaluated using Spearman analysis, and the diagnostic performance of these proteins in neurosyphilis was assessed using receiver operating characteristic curve. RESULTS: A total of 102 differentially expressed proteins between neurosyphilis and non-neurosyphilis were identified. The levels of significantly elevated neutrophil-associated proteins (CXCL1, CXCL8, G-CSF, LCN2, MMP8, and MMP9) in neurosyphilis positively correlated with white blood cell counts, rapid plasma regain (RPR) titer, and protein concentration in CSF. The combination of CSF CXCL8, MMP9, and LCN2 yielded an area under the curve of 0.92 for diagnosing neurosyphilis, surpassing that of CSF RPR. CONCLUSIONS: CXCL1, CXCL8, G-CSF, LCN2, MMP8, and MMP9 could be associated with central nervous system damage of neurosyphilis. The combination of CSF CXCL8, MMP9, and LCN2 is a promising biomarker for diagnosing neurosyphilis.

Knockdown of LncRNA Lcn2-204 alleviates sepsis-induced myocardial injury by regulation of iron overload and ferroptosis.

Ferroptosis is an iron-dependent programmed cell death form resulting from lipid peroxidation damage, it plays a key role in organ damage and tumor development from various causes. Sepsis leads to severe host response after infection with high mortality. The long non-coding RNAs (LncRNAs) are involved in different pathophysiological mechanisms of multiple diseases. Here, we used cecal ligation and puncture (CLP) operation to mimic sepsis induced myocardial injury (SIMI) in mouse model, and LncRNAs and mRNAs were profiled by Arraystar mouse LncRNA Array V3.0. Based on the microarray results, 552 LncRNAs and 520 mRNAs were differentially expressed in the sham and CLP groups, among them, LncRNA Lcn2-204 was the highest differentially expressed up-regulated LncRNA. Iron metabolism disorder was involved in SIMI by bioinformatics analysis, meanwhile, myocardial iron content and lipocalin-2 (Lcn2) protein expressions were increased. The CNC network comprised 137 positive interactions and 138 negative interactions. Bioinformatics analysis showed several iron-related terms were enriched and six genes (Scara5, Tfrc, Lcn2, Cp, Clic5, Ank1) were closely associated with iron metabolism. Then, we constructed knockdown LncRNA Lcn2-204 targeting myocardium and found that it ameliorated cardiac injury in mouse sepsis model through modulating iron overload and ferroptosis. In addition, we found that LncRNA Lcn2-204 was involved in the regulation of Lcn2 expression in septic myocardial injury. Based on these findings, we conclude that iron overload and ferroptosis are the key mechanisms leading to myocardial injury in sepsis, knockdown of LncRNA Lcn2-204 plays the cardioprotective effect through inhibition of iron overload, ferroptosis and Lcn2 expression. It may provide a novel therapeutic approach to ameliorate sepsis-induced myocardial injury.

Acute high-dose MitoQ does not increase urinary kidney injury markers in healthy adults: a randomized crossover trial.

Several human studies have used the mitochondrial antioxidant MitoQ. Recent in vitro data indicating that MitoQ may induce nephrotoxicity caused concern regarding the safety of MitoQ on the kidneys, but the doses were supraphysiological. Therefore, we sought to determine whether acute MitoQ elicits changes in urinary biomarkers associated with tubular injury in healthy adults with our hypothesis being there would be no changes. Using a randomized crossover design, 32 healthy adults (16 females and 16 males, 29 ± 11 yr old) consumed MitoQ (100-160 mg based on body mass) or placebo capsules. We obtained serum samples and a 4- to 6-h postcapsule consumption urine sample. We assessed creatinine clearance and urine kidney injury biomarkers including the chitinase 3-like-1 gene product YKL-40, kidney-injury marker-1, monocyte chemoattractant protein-1, epidermal growth factor, neutrophil gelatinase-associated lipocalin, interleukin-18, and uromodulin using multiplex assays. We used t tests, Wilcoxon tests, and Hotelling's T2 to assess global differences in urinary kidney injury markers between conditions. Acute MitoQ supplementation did not influence urine flow rate (P = 0.086, rrb = 0.39), creatinine clearance (P = 0.085, rrb = 0.42), or urinary kidney injury markers (T22,8 = 30.6, P = 0.121, univariate ps > 0.064). Using exploratory univariate analysis, MitoQ did not alter individual injury markers compared with placebo (e.g., placebo vs. MitoQ: YKL-40, 507 ± 241 vs. 442 ± 236 pg/min, P = 0.241; kidney injury molecule-1, 84.1 ± 43.2 vs. 76.2 ± 51.2 pg/min, P = 0.890; and neutrophil gelatinase-associated lipocalin, 10.8 ± 10.1 vs. 9.83 ± 8.06 ng/min, P = 0.609). In conclusion, although longer-term surveillance and data are needed in clinical populations, our findings suggest that acute high-dose MitoQ had no effect on urinary kidney injury markers in healthy adults.NEW & NOTEWORTHY We found acute high-dose mitochondria-targeted antioxidant (MitoQ) supplementation was not nephrotoxic and had no effect on markers of acute kidney injury in healthy adults. These findings can help bolster further confidence in the safety of MitoQ, particularly for future investigations seeking to examine the role of mitochondrial oxidative stress, via acute MitoQ supplementation, on various physiological outcomes.

Parental obesity predisposes offspring to kidney dysfunction and increased susceptibility to ischemia-reperfusion injury in a sex-dependent manner.

Although obesity is recognized as a risk factor for cardiorenal and metabolic diseases, the impact of parental obesity on the susceptibility of their offspring to renal injury at adulthood is unknown. We examined the impact of parental obesity on offspring kidney function, morphology, and markers of kidney damage after acute kidney injury (AKI). Offspring from normal (N) diet-fed C57BL/6J parents were fed either N (NN) or a high-fat (H) diet (NH) from weaning until adulthood. Offspring from obese H diet-fed parents were fed N (HN) or H diet (HH) after weaning. All offspring groups were submitted to bilateral AKI by clamping the left and right renal pedicles for 30 min. Compared with male NH and NN offspring from lean parents, male HH and HN offspring from obese parents exhibited higher kidney injury markers such as urinary, renal osteopontin, plasma creatinine, urinary albumin excretion, and neutrophil gelatinase-associated lipocalin (NGAL) levels, and worse histological injury score at 22 wk of age. Only albumin excretion and NGAL were elevated in female HH offspring from obese parents compared with lean and obese offspring from lean parents. We also found an increased mortality rate and worse kidney injury scores after AKI in male offspring from obese parents, regardless of the diet consumed after weaning. Female offspring were protected from major kidney injury after AKI. These results indicate that parental obesity leads to increased kidney injury in their offspring after ischemia-reperfusion in a sex-dependent manner, even when their offspring remain lean.NEW & NOTEWORTHY Offspring from obese parents are more susceptible to kidney injury and worse outcomes following an acute ischemia-reperfusion insult. Male, but not female, offspring from obese parents exhibit increased blood pressure early in life. Female offspring are partially protected against major kidney injury induced by ischemia-reperfusion.

Sex-disaggregated analysis of acute kidney injury in hospitalized children with sickle cell anemia in Uganda.

A growing body of research is categorizing sex differences in both sickle cell anemia (SCA) and acute kidney injury (AKI); however, most of this work is being conducted in high-resource settings. Here, we evaluated risk factors and clinical parameters associated with AKI and AKI severity, stratified by sex, in a cohort of children hospitalized with SCA and vaso-occlusive pain crisis (VOC). The purpose of this study was to explore sex disparities in a high-risk, vulnerable population. This study was a secondary analysis of data collected from a cohort of Ugandan children between 2 and 18 yr of age prospectively enrolled. A total of 185 children were enrolled in the primary study; 41.6% were female and 58.4% were male, with a median age of 8.9 yr. Incident or worsening AKI (P = 0.026) occurred more frequently in female compared with male children, despite no differences in AKI on admission. Female children also had altered markers of renal function including higher creatinine levels at admission (P = 0.03), higher peak creatinine (P = 0.006), and higher urine neutrophil gelatinase-associated lipocalin (NGAL) at admission (P = 0.003) compared with male children. Female children had elevated total (P = 0.045) and conjugated bilirubin at admission (P = 0.02) compared with male children and higher rates of hematuria at admission (P = 0.004). Here, we report sex differences in AKI in children with SCA and VOC, including increased incidence and worsening of AKI in female pediatric patients, in association with an increase in biological indicators of poor renal function including creatinine, estimated glomerular filtration rate, and NGAL.NEW & NOTEWORTHY In this study, we report an increased risk of developing acute kidney injury (AKI) during hospitalization, worsening AKI, and death among females with sickle cell anemia (SCA) hospitalized with an acute pain crisis compared with males. The sex differences in AKI were not explained by socioeconomic differences, severity of pain, or disease severity among females compared with males. Together, these data suggest that female children with SCA may be at increased risk of AKI.

Deceased donor kidney function and branched chain amino acid metabolism during ex vivo normothermic perfusion.

Current kidney perfusion protocols are not optimized for addressing the ex vivo physiological and metabolic needs of the kidney. Ex vivo normothermic perfusion may be utilized to distinguish high-risk kidneys to determine suitability for transplantation. Here, we assessed the association of tissue metabolic changes with changes in a kidney injury biomarker and functional parameters in eight deceased donor kidneys deemed unsuitable for transplantation during a 12-hour ex vivo normothermic perfusion. The kidneys were grouped into good and poor performers based on blood flow and urine output. The mean age of the deceased kidney donors was 43 years with an average cold ischemia time of 37 hours. Urine output and creatinine clearance progressively increased and peaked at six hours post-perfusion among good performers. Poor performers had 71 ng/ml greater (95% confidence interval 1.5, 140) urinary neutrophil gelatinase-associated lipocalin at six hours compared to good performers corresponding to peak functional differences. Organ performance was distinguished by tissue metabolic differences in branched chain amino acid metabolism and that their tissue levels negatively correlated with urine output among all kidneys at six hours. Tissue lipid profiling showed poor performers were highlighted by the accumulation of membrane structure components including glycerolipids and sphingolipids at early perfusion time points. Thus, we showed that six hours is needed for kidney function recovery during ex vivo normothermic perfusion and that branched chain amino acid metabolism may be a major determinant of organ function and resilience.

A prospective, multicenter, three-cohort study evaluating contrast-induced acute kidney injury (CI-AKI) in patients with cirrhosis.

BACKGROUND & AIMS: Nephrotoxicity of intravenous iodinated contrast media (ICM) in cirrhosis is still a debated issue, due to scarce, low-quality and conflicting evidence. This study aims to evaluate the incidence and predisposing factors of acute kidney injury (AKI) in patients with cirrhosis undergoing contrast-enhanced computed tomography (CECT). METHODS: We performed a prospective, multicenter, cohort study including 444 inpatients, 148 with cirrhosis (cohort 1) and 163 without cirrhosis (cohort 3) undergoing CECT and 133 with cirrhosis (cohort 2) unexposed to ICM. Kidney function parameters were assessed at T0, 48-72 h (T1), 5 and 7 days after CECT/enrollment. Urinary neutrophil gelatinase-associated lipocalin (U-NGAL) was measured in 50 consecutive patients from cohort 1 and 50 from cohort 2 as an early biomarker of tubular damage. RESULTS: AKI incidence was not significantly increased in patients with cirrhosis undergoing CECT (4.8%, 1.5%, 2.5% in cohorts 1, 2, 3 respectively, p = n.s.). Most AKI cases were mild and transient. The presence of concomitant infections was the only independent predictive factor of contrast-induced AKI (odds ratio 22.18; 95% CI 2.87-171.22; p = 0.003). No significant modifications of U-NGAL between T0 and T1 were detected, neither in cohort 1 nor in cohort 2 (median ΔU-NGAL: +0.2 [-7.6 to +5.5] ng/ml, +0.0 [-6.8 to +9.5] ng/ml, respectively [p = 0.682]). CONCLUSIONS: AKI risk after CECT in cirrhosis is low and not significantly different from that of the general population or of the cirrhotic population unexposed to ICM. It mostly consists of mild and rapidly resolving episodes of renal dysfunction and it is not associated with tubular kidney injury. Patients with ongoing infections appear to be the only ones at higher risk of AKI. IMPACT AND IMPLICATIONS: Nephrotoxicity due to intravenous iodinated contrast media (ICM) in patients with cirrhosis is still a debated issue, as the available evidence is limited and based on very heterogeneous studies, often conducted on small and retrospective cohorts. In this prospective three-cohort study we found that intravenous administration of ICM was associated with a low risk of AKI, similar to that of the general population and to that of patients with cirrhosis unexposed to ICM. Patients with ongoing infections were the only ones to have a significantly increased risk of contrast-induced AKI. Therefore, the actual recommendations of performing contrast imaging studies cautiously in cirrhosis do not seem to be reasonable anymore, with the exception of infected patients, who have a significantly higher risk of contrast-induced AKI.

Characterization of cells expressing lipocalin-2 (LCN2) as a reporter.

Lipocalin-2 (LCN2), an effector molecule of the innate immune system that is small enough to be tagged as a reporter molecule, can be coupled with the ferric ion through a siderophore such as enterobactin (Ent). Mintbody (modification-specific intracellular antibody) can track a posttranslational protein modification in epigenetics. We constructed plasmids expressing the LCN2 hybrid of mintbody to examine the potential of LCN2 as a novel reporter for magnetic resonance imaging (MRI). Cells expressing the LCN2 hybrid of mintbody showed proper expression and localization of the hybrid and responded reasonably to Ent, suggesting their potential for in vivo study by MRI.

Empagliflozin's role in early tubular protection for type 2 diabetes patients.

BACKGROUND: Patients with type 2 diabetes often face early tubular injury, necessitating effective treatment strategies. This study aimed to evaluate the impact of the SGLT2 inhibitor empagliflozin on early tubular injury biomarkers in type 2 diabetes patients with normoalbuminuria. METHODS: A randomized controlled clinical study comprising 54 patients selected based on specific criteria was conducted. Patients were divided into an intervention group (empagliflozin, n = 27) and a control group (n = 27) and treated for 6 weeks. Tubular injury biomarkers KIM-1 and NGAL were assessed pre- and post-treatment. RESULTS: Both groups demonstrated comparable baseline characteristics. Post-treatment, fasting and postprandial blood glucose levels decreased similarly in both groups. The intervention group exhibited better improvements in total cholesterol, low-density lipoprotein, and blood uric acid levels. Renal function indicators, including UACR and eGFR, showed greater enhancements in the intervention group. Significant reductions in KIM-1 and NGAL were observed in the intervention group. CONCLUSION: Treatment with empagliflozin in type 2 diabetes patients with normoalbuminuria led to a notable decrease in tubular injury biomarkers KIM-1 and NGAL. These findings highlight the potential of SGLT2 inhibitors in early tubular protection, offering a new therapeutic approach.

Long-term impact of maternal obesity on the gliovascular unit and ephrin signaling in the hippocampus of adult offspring.

BACKGROUND: Children born to obese mothers are at increased risk of developing mood disorders and cognitive impairment. Experimental studies have reported structural changes in the brain such as the gliovascular unit as well as activation of neuroinflammatory cells as a part of neuroinflammation processing in aged offspring of obese mothers. However, the molecular mechanisms linking maternal obesity to poor neurodevelopmental outcomes are not well established. The ephrin system plays a major role in a variety of cellular processes including cell-cell interaction, synaptic plasticity, and long-term potentiation. Therefore, in this study we determined the impact of maternal obesity in pregnancy on cortical, hippocampal development, vasculature and ephrin-A3/EphA4-signaling, in the adult offspring in mice. METHODS: Maternal obesity was induced in mice by a high fat/high sugar Western type of diet (HF/HS). We collected brain tissue (prefrontal cortex and hippocampus) from 6-month-old offspring of obese and lean (control) dams. Hippocampal volume, cortical thickness, myelination of white matter, density of astrocytes and microglia in relation to their activity were analyzed using 3-D stereological quantification. mRNA expression of ephrin-A3, EphA4 and synaptic markers were measured by qPCR in the brain tissue. Moreover, expression of gap junction protein connexin-43, lipocalin-2, and vascular CD31/Aquaporin 4 were determined in the hippocampus by immunohistochemistry. RESULTS: Volume of hippocampus and cortical thickness were significantly smaller, and myelination impaired, while mRNA levels of hippocampal EphA4 and post-synaptic density (PSD) 95 were significantly lower in the hippocampus in the offspring of obese dams as compared to offspring of controls. Further analysis of the hippocampal gliovascular unit indicated higher coverage of capillaries by astrocytic end-feet, expression of connexin-43 and lipocalin-2 in endothelial cells in the offspring of obese dams. In addition, offspring of obese dams demonstrated activation of microglia together with higher density of cells, while astrocyte cell density was lower. CONCLUSION: Maternal obesity affects brain size, impairs myelination, disrupts the hippocampal gliovascular unit and decreases the mRNA expression of EphA4 and PSD-95 in the hippocampus of adult offspring. These results indicate that the vasculature-glia cross-talk may be an important mediator of altered synaptic plasticity, which could be a link between maternal obesity and neurodevelopmental/neuropsychiatric disorders in the offspring.

Increased plasma lipocalin-2 levels are associated with nonmotor symptoms and neuroimaging features in patients with Parkinson's disease.

Lipocalin-2 (LCN2) is essential for the regulation of neuroinflammation and cellular uptake of iron. This study aimed to evaluate plasma LCN2 levels and explore their correlation with clinical and neuroimaging features in Parkinson's disease (PD) patients. Enzyme-linked immunosorbent assay (ELISA) was used to measure plasma LCN2 levels in 120 subjects. Evaluation of motor symptoms and nonmotor symptoms in PD patients was assessed by the associated scales. Voxel-based morphometry (VBM) was used to evaluate brain volume alterations, and quantitative susceptibility mapping (QSM) was used to quantitatively analyze brain iron deposition in 46 PD patients. Plasma LCN2 levels were significantly higher in PD patients than those in healthy controls. LCN2 levels were negatively correlated with Montreal Cognitive Assessment (MoCA) scores, total brain gray matter volume (GMV), and GMV/total intracranial volume (TIV) ratio, but positively correlated with Hamilton Anxiety Rating Scale (HAMD) scores and mean QSM values of the bilateral substantial nigra (SN). Receiver operating characteristic (ROC) curves confirmed that plasma LCN2 levels had good predictive accuracy for PD. The results suggest that plasma LCN2 levels have potential as a biomarker for the diagnosis of PD. LCN2 may be a therapeutic target for neuroinflammation and brain iron deposition.

Dynamic changes in the real-time glomerular filtration rate and kidney injury markers in different acute kidney injury models.

In this study, we dynamically monitored the glomerular filtration rate and other assessment of renal function and markers of injury in various mice models of acute kidney injury. Male C57BL/6 mice were utilized to establish acute kidney injury models of sepsis, ischemia reperfusion, cisplatin, folic acid, aristolochic acid and antibiotic. In addition to the real time glomerular filtration rate, renal LCN-2 and HAVCR-1 mRNA expression levels, and serum creatinine, urea nitrogen and cystatin c levels were also used to evaluate renal function. In addition, the protein levels of LCN-2 and HAVCR-1 in renal, serum and urine were measured. Our results demonstrated that the changes in biomarkers always lagged the real time glomerular filtration rate during the progression and recovery of renal injury. Cystatin-c can reflect renal injury earlier than other markers, but it remains higher in the recovery stage. Perhaps the glomerular filtration rate does not reflect the greater injury caused by vancomycin plus piperacillin.