Pellino1 orchestrates gut-kidney axis to perpetuate septic acute kidney injury through activation of STING pathway and NLRP3 inflammasome.

AIMS: Intestinal barrier dysfunction is the initial and propagable factor of sepsis in which acute kidney injury (AKI) has been considered as a common life-threatening complication. Our recent study identifies the regulatory role of Pellino1 in tubular death under inflammatory conditions in vitro. The objective of our current study is to explore the impact of Pellino1 on gut-kidney axis during septic AKI and uncover the molecular mechanism (s) underlying this process. MATERIALS AND METHODS: Immunohistochemistry (IHC) was conducted to evaluate Pellino1 and NOD-like receptor thermal protein domain associated protein 3 (NLRP3) levels in renal biopsies from critically ill patients with a clinical diagnosis of sepsis. Functional and mechanistic studies were characterized in septic models of the Peli-knockout (Peli1-/-) mice by histopathological staining, enzyme-linked immunosorbent assay (ELISA), flow cytometry, immunofluorescence, biochemical detection, CRISPR/Cas9-mediated gene editing and intestinal organoid. KEY FINDINGS: Pellino1, together with NLRP3, are highly expressed in renal biopsies from critically ill patients diagnosed with sepsis and kidney tissues of septic mice. The Peli1-/- mice with sepsis become less prone to develop AKI and have markedly compromised NLRP3 activation in kidney. Loss of Peli1 endows septic mice refractory to intestinal inflammation, barrier permeability and enterocyte apoptosis that requires stimulator of interferons genes (STING) pathway. Administration of STING agonist DMXAA deteriorates AKI and mortality of septic Peli1-/- mice in the presence of kidney-specific NLRP3 reconstitution. SIGNIFICANCE: Our studies suggest that Pellino1 has a principal role in orchestrating gut homeostasis towards renal pathophysiology, thus providing a potential therapeutic target for septic AKI.

A neutrophil elastase inhibitor, sivelestat, attenuates sepsis-induced acute kidney injury by inhibiting oxidative stress.

Background: Sivelestat, a selective inhibitor of neutrophil elastase (NE), can mitigate sepsis-related acute lung injury. However, the role of sivelestat in inhibiting oxidative stress and attenuating sepsis-related acute kidney injury (AKI) remains unclear. Here, we reported the effects of sivelestat against oxidative stress-induced AKI by suppressing the production of oxidative stress indicators. Materials and methods: A male Sprague-Dawley rat model of sepsis was established by cecal ligation and puncture (CLP). Sivelestat or normal saline was administered into jugular vein with a sustained-release drug delivery system. Indicators of inflammation and AKI, including white blood cells (WBC), neutrophils, lymphocytes, C-reactive proteins (CRP), procalcitonin (PCT), blood urea nitrogen (BUN), creatinine (Cr) and uric acid (UA), were assessed at 24 h post-sivelestat treatment. Indicators of liver injury, including direct bilirubin (DBIL), indirect bilirubin (IBIL), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), were also assessed at 24 h post-sivelestat treatment. Indicators of oxidative stress, including superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px), were assessed at 12 h and 24 h post-sivelestat treatment. At 24 h post-sivelestat treatment, H&E staining of kidney and liver tissue was performed to observe pathological alterations. Results: At 24 h post normal saline or sivelestat (0.2 g/kg body weight) treatment, WBC, neutrophil, CRP, PCT, MDA, BUN, Cr, UA, AST, ALT, DBIL and IBIL were increased, while SOD and GSH-Px were decreased, in septic rats treated with normal saline compared with that in non-septic rats treated with normal saline (all p < 0.05). The changes of these indicators were reversed in septic rats treated with sivelestat compared with that in septic rats treated with normal saline (all p < 0.05). Similar results were found regarding the levels of oxidative stress indicators at 12 h post-sivelestat treatment. The degenerative histopathological changes in both kidney and liver tissues were ameliorated upon sivelestat treatment. Conclusions: Sivelestat plays a protective role in sepsis-related AKI by inhibiting oxidative stress. Our study reveals a possible therapeutic potential of sivelestat for oxidative stress-induced AKI.

Targeting SLC22A5 fosters mitophagy inhibition-mediated macrophage immunity against septic acute kidney injury upon CD47-SIRPα axis blockade.

Efferocytosis of apoptotic neutrophils (PMNs) by macrophages is helpful for inflammation resolution and injury repair, but the role of efferocytosis in intrinsic nature of macrophages during septic acute kidney injury (AKI) remains unknown. Here we report that CD47 and signal regulatory protein alpha (SIRPα)-the anti-efferocytotic 'don't eat me' signals-are highly expressed in peripheral blood mononuclear cells (PBMCs) from patients with septic AKI and kidney samples from mice with polymicrobial sepsis and endotoxin shock. Conditional knockout (CKO) of SIRPA in macrophages ameliorates AKI and systemic inflammation response in septic mice, accompanied by an escalation in mitophagy inhibition of macrophages. Ablation of SIRPA transcriptionally downregulates solute carrier family 22 member 5 (SLC22A5) in the lipopolysaccharide (LPS)-stimulated macrophages that efferocytose apoptotic neutrophils (PMNs). Targeting SLC22A5 renders mitophagy inhibition of macrophages in response to LPS stimuli, improves survival and deters development of septic AKI. Our study supports further clinical investigation of CD47-SIRPα signalling in sepsis and proposes that SLC22A5 might be a promising immunotherapeutic target for septic AKI.

Effects of whole-body vibration training on physical function, activities of daily living, and quality of life in patients with stroke: a systematic review and meta-analysis.

Purpose: This systematic review and meta-analysis aimed to evaluate the efficacy of whole-body vibration training (WBVT) in patients with stroke, specifically focusing on its effects on physical function, activities of daily living (ADL), and quality of life (QOL). Additionally, potential moderators influencing WBVT outcomes were explored. Methods: We conducted a systematic search of PubMed, Embase, and Cochrane Library from inception to September 2022. Eligible studies were randomized controlled trials employing WBVT in patients with stroke. Two investigators independently extracted the data and calculated the standardized mean difference (SMD) using random-effect models. Results: Twenty-five studies involving 991 patients were included in this meta-analysis. WBVT demonstrated significant reductions in spasticity (SMD = -0.33, 95% CI = -0.61 to -0.06, p = 0.02), improvements in motor function (SMD = 0.39, 95% CI = 0.16 to 0.61, p < 0.01), and enhancements in balance function (SMD = 0.28, 95% CI = 0.09 to 0.47, p < 0.01) in patients with stroke. However, no significant effects were observed for gait (SMD = -0.23, 95% CI = -0.50 to 0.04, p = 0.10), ADL (SMD = -0.01, 95% CI = -0.46 to 0.44, p = 0.97), or QOL (SMD = 0.12, 95% CI = -0.30 to 0.53, p = 0.59). Subgroup analyses revealed that variable frequency vibration and side-alternating vibration exhibited significant efficacy in reducing spasticity and improving motor and balance functions, while fixed frequency vibration and vertical vibration did not yield significant therapeutic benefits in these domains. Conclusion: Our findings indicate that WBVT may serve as a viable adjunct therapy for stroke patients to alleviate spasticity and enhance motor and balance functions. Variable frequency and side-alternating vibration appear to be crucial factors influencing the therapeutic effects of WBVT on these dysfunctions. Nonetheless, WBVT did not show significant effects on gait, ADL, or QOL in stroke patients. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, identifier (CRD42022384319).

Auto- and paracrine rewiring of NIX-mediated mitophagy by insulin-like growth factor-binding protein 7 in septic AKI escalates inflammation-coupling tubular damage.

AIMS: Inflammation-coupling tubular damage (ICTD) contributes to pathogenesis of septic acute kidney injury (AKI), in which insulin-like growth factor-binding protein 7 (IGFBP-7) serves as a biomarker for risk stratification. The current study aims to discern how IGFBP-7 signalling influences ICTD, the mechanisms that underlie this process and whether blockade of the IGFBP-7-dependent ICTD might have therapeutic value for septic AKI. MATERIALS AND METHODS: In vivo characterization was carried out in B6/JGpt-Igfbp7em1Cd1165/Gpt mice subjected to cecal ligation and puncture (CLP). Transmission electron microscopy, immunofluorescence, flow cytometry, immunoblotting, ELISA, RT-qPCR and dual-luciferase reporter assays were used to determine mitochondrial functions, cell apoptosis, cytokine secretion and gene transcription. KEY FINDINGS: ICTD augments the transcriptional activity and protein secretion of tubular IGFBP-7, which enables an auto- and paracrine signalling via deactivation of IGF-1 receptor (IGF-1R). Genetic knockout (KO) of IGFBP-7 provides renal protection, improves survival and resolves inflammation in murine models of cecal ligation and puncture (CLP), while administering recombinant IGFBP-7 aggravates ICTD and inflammatory invasion. IGFBP-7 perpetuates ICTD in a NIX/BNIP3-indispensable fashion through dampening mitophagy that restricts redox robustness and preserves mitochondrial clearance programs. Adeno-associated viral vector 9 (AAV9)-NIX short hairpin RNA (shRNA) delivery ameliorates the anti-septic AKI phenotypes of IGFBP-7 KO. Activation of BNIP3-mediated mitophagy by mitochonic acid-5 (MA-5) effectively attenuates the IGFBP-7-dependent ICTD and septic AKI in CLP mice. SIGNIFICANCE: Our findings identify IGFBP-7 is an auto- and paracrine manipulator of NIX-mediated mitophagy for ICTD escalation and propose that targeting the IGFBP-7-dependent ICTD represents a novel therapeutic strategy against septic AKI.

[Effect of navel acupuncture on bladder emptying function in patients with urinary retention after stroke].

OBJECTIVE: To observe the effect of navel acupuncture on bladder emptying function in patients with urinary retention after stroke based on the conventional treatment. METHODS: A total of 106 patients with urinary retention after stroke were randomly divided into an observation group (53 cases, 3 cases dropped off) and a control group (53 cases, 3 cases dropped off). Patients in the control group were treated with drugs, catheterization and bladder function rehabilitation training. On the basis of the treatment in the control group, the observation group was treated with navel acupuncture, 30 min each time, once every other day, for 4 weeks. The bladder residual urine volume, spontaneous urination volume and catheterization times before and after treatment were compared between the two groups, and the clinical efficacy was evaluated. RESULTS: After treatment, in the two groups, the bladder residual urine volume and catheterization times were lower than those before treatment (P<0.01), and the spontaneous urination volume was higher than that before treatment (P<0.01); the bladder residual urine volume and catheterization times in the observation group were less than those in the control group (P<0.05, P<0.01), and the spontaneous urination volume was higher than that in the control group (P<0.01). The effective rate of the observation group was 90.0 % (45/50), which was higher than 72.0 % (36/50) in the control group (P<0.05). CONCLUSION: On the basis of conventional treatment, navel acupuncture can effectively improve the bladder emptying function of patients with urinary retention after stroke.

Tubule-mitophagic secretion of SerpinG1 reprograms macrophages to instruct anti-septic acute kidney injury efficacy of high-dose ascorbate mediated by NRF2 transactivation.

High-dose ascorbate confers tubular mitophagy responsible for septic acute kidney injury (AKI) amelioration, yet its biological roles in immune regulation remain poorly understood. Methods: The role of tubular mitophagy in macrophage polarization upon high-dose ascorbate treatment was assessed by fluorescence-activated cell sorter analysis (FACS) in vitro and by immunofluorescence in AKI models of LPS-induced endotoxemia (LIE) from Pax8-cre; Atg7 flox/flox mice. The underlying mechanisms were revealed by RNA-sequencing, gene set enrichment analysis (GSEA), luciferase reporter, chromatin immunoprecipitation (ChIP) and adeno-associated viral vector serotype 9 (AAV9) delivery assays. Results: High-dose ascorbate enables conversion of macrophages from a pro-inflammatory M1 subtype to an anti-inflammatory M2 subtype in murine AKI models of LIE, leading to decreased renal IL-1ß and IL-18 production, reduced mortality and alleviated tubulotoxicity. Blockade of tubular mitophagy abrogates anti-inflammatory macrophages polarization under the high-dose ascorbate-exposed coculture systems. Similar abrogations are verified in LIE mice with tubular epithelium-specific ablation of Atg7, where the high-dose ascorbate-inducible renal protection and survival improvement are substantially weaker than their control littermates. Mechanistically, high-dose ascorbate stimulates tubular secretion of serpin family G member 1 (SerpinG1) through maintenance of mitophagy, for which nuclear factor-erythroid 2 related factor 2 (NRF2) transactivation is required. SerpinG1 perpetuates anti-inflammatory macrophages to prevent septic AKI, while kidney-specific disruption of SerpinG1 by adeno-associated viral vector serotype 9 (AAV9)-short hairpin RNA (shRNA) delivery thwarts the anti-inflammatory macrophages polarization and anti-septic AKI efficacy of high-dose ascorbate. Conclusion: Our study identifies SerpinG1 as an intermediate of tubular mitophagy-orchestrated myeloid function during septic AKI and reveals a novel rationale for ascorbate-based therapy.

Redox-sensitive MAPK and Notch3 regulate fibroblast differentiation and activation: a dual role of ERK1/2.

Myofibroblastic transformation, characterized by upregulation of α-smooth muscle actin in response to profibrotic agents such as TGF-ß1, is considered as a major event leading to fibrosis. The mechanistic basis linking myofibroblast differentiation to idiopathic pulmonary fibrosis and the disease treatment remain elusive. In this study, we studied roles of MAPK, Notch, and reactive oxygen species (ROS) during the differentiation of IMR-90 lung fibroblasts at basal level and induced by TGF-ß1. Our results demonstrated that ROS-dependent activation of p38, JNK1/2 and Notch3 promoted basal and TGF-ß1-induced differentiation and expression of extracellular matrix proteins. In stark contrast, ERK1/2 was suppressed by ROS and exhibited an inhibitory effect on the differentiation but showed a weak promotion on the expression of extracellular matrix proteins. TGF-ß1-induced Notch3 expression depended on p38 and JNK1/2. Interestingly, Notch3 was also downstream of ERK1/2, suggesting a complex role of ERK1/2 in lung function. Our results suggest a novel ROS-mediated shift of dominance from the inhibitory ERK1/2 to the stimulatory p38, JNK1/2 and Notch3 during the pathological progression of IPF. Thus, targeting ERK1/2 signaling for activation and p38, JNK1/2 and Notch3 for inhibition may be of clinical potential against lung fibrosis.

Serotonin transporter polymorphic region 5-HTTLPR modulates risk for Parkinson's disease.

The association between the serotonin transporter gene (SLC6A4) polymorphisms, that is, 5-HTTLPR and rs25531, and Parkinson's disease (PD) remains to be further defined. We investigated this relationship in a Chinese cohort that comprised 504 PD patients and 504 controls. A total of 8 haplotypes and 14 genotypes of SLC6A4 were found in this population including a new variant of 5-HTTLPR, that is, 20G. Our results presented that 5-HTTLPR was associated with an aggravated risk for PD (p = 0.005). The rs25531 alone is not associated with PD susceptibility. However, in a sub-classification based on the impact of 5-HTTLPR and rs25531 on 5-HTT expression, we observed a significant difference in 5-HTT expressing distribution in the cohort, accompanied by an apparently lower level of 5-HTT high expressing group, that is, the LALA genotype, in the PD patients. Taken together, our data provide novel insight in support that the SLC6A4 polymorphisms, particularly 5-HTTLPR, and the serotonergic system are associated with PD etiology.

Paroxetine ameliorates lipopolysaccharide-induced microglia activation via differential regulation of MAPK signaling.

BACKGROUND: Paroxetine, a selective serotonin reuptake inhibitor for counteracting depression, has been recently suggested as having a role in prevention of dopaminergic neuronal degeneration in substantia nigra, a hallmark of Parkinson's disease (PD). The pathogenesis of this type of neurological disorders often involves the activation of microglia and associated inflammatory processes. Thus in this study we aimed to understand the role of paroxetine in microglia activation and to elucidate the underlying mechanism(s). METHODS: BV2 and primary microglial cells were pretreated with paroxetine and stimulated with lipopolysaccharide (LPS). Cells were assessed for the responses of pro-inflammatory mediator and cytokines, and the related signaling pathways were evaluated and analyzed in BV2 cells. RESULTS: Paroxetine significantly inhibited LPS-induced production of nitric oxide (NO) and pro-inflammatory cytokines such as TNF-α and IL-1ß. Further analysis showed inducible nitric oxide synthase (iNOS) and mRNA expression of TNF-α and IL-1ß were attenuated by paroxetine pretreatment. Analyses in signaling pathways demonstrated that paroxetine led to suppression of LPS-induced JNK1/2 activation and baseline ERK1/2 activity, but had little effect on the activation of p38 and p65/NF-κB. Interference with specific inhibitors revealed that paroxetine-mediated suppression of NO production was via JNK1/2 pathway while the cytokine suppression was via both JNK1/2 and ERK1/2 pathways. Furthermore, conditioned media culture showed that paroxetine suppressed the microglia-mediated neurotoxicity. CONCLUSIONS: Paroxetine inhibits LPS-stimulated microglia activation through collective regulation of JNK1/2 and ERK1/2 signaling. Our results indicate a potential role of paroxetine in neuroprotection via its anti-neuroinflammatory effect besides targeting for depression.