Paraoxonase 1 Ameliorates Renal Lipotoxicity by Activating Lipophagy and Inhibiting Pyroptosis.

Several studies in recent years have shown that lipid overload causes lipotoxic damage to the kidney, and oxidative stress, inflammation, and autophagic arrest are all important mechanisms of renal lipotoxicity. However, effective measures with therapeutic effects on renal lipotoxicity are limited. The present study indicated the protective effect of the paraoxonase 1 (PON1) against renal lipotoxicity in high-fat diet-fed scavenger receptor class B type I-deficient (SR-BI-/-) mice. The results showed that SR-BI-/- mice exhibited significant renal pathologic characteristics, such as oxidative stress, inflammation, and fibrosis, under a normal chow diet, and were accompanied by dyslipidemia and reduced plasma PON1 activity and renal PON1 levels. PON1 overexpression significantly attenuated the above pathologic changes in the kidneys of SR-BI-/- mice fed with a high-fat diet. Mechanistically, PON1 may ameliorate renal oxidative stress by reducing reactive oxygen species production, reduce renal lipid accumulation by inhibiting AKT/mechanistic target of rapamycin kinase pathway to activate lipophagy, and reduce the occurrence of inflammation and cell death by inhibiting Nod-like receptor family protein 3 inflammasome-mediated pyroptosis. The present study is the first to show that PON1 overexpression can effectively alleviate renal lipotoxicity injury, and PON1 may be a promising therapeutic strategy for the treatment of renal lipotoxicity-related diseases.

Review of the subgenus Tarpheion of the genus Blacus Nees (Hymenoptera, Braconidae, Brachistinae) from China, with description of nine new species and eight new records.

An updated key to the currently known species of the subgenus Tarpheion van Achterberg, 1976 (Hymenoptera, Braconidae, Blacus) in China is provided. Nine new species are proposed, B. (T.) adelphius sp. nov., B. (T.) frontalis sp. nov., B. (T.) gilvus sp. nov., B. (T.) hainanensis sp. nov., B. (T.) parilis sp. nov., B. (T.) reticulatus sp. nov., B. (T.) sculptilis sp. nov., B. (T.) tanae sp. nov., and B. (T.) wuyishanensis sp. nov. Eight species, B. (T.) achterbergi Haeselbarth, 1976, B. (T.) albiventris van Achterberg, 1988, B. (T.) angichorus van Achterberg, 1988, B. (T.) antennalis van Achterberg, 1988, B. (T.) apicalis van Achterberg, 1976, B. (T.) artomandibularis van Achterberg, 1976, B. (T.) bicolor van Achterberg, 1988, and B. (T.) soror van Achterberg, 1988, are newly recorded from China.

Risk factors of disease activity and renal damage in patients with systemic lupus erythematosus.

PURPOSE: To evaluate the clinical features of patients with Systemic Lupus Erythematosus (SLE) and explore the risk factors of disease activity and renal damage. METHODS: A retrospective study involving 194 patients were performed. Patients were divided into lupus nephritis (LN) group (63.40%) and non-LN group (36.60%), different disease activity group, and different renal function group according to the clinical data. Multivariate logistic regression analysis showed that albumin (ALB), uric acid (UC), total cholesterol (TC), and anti-dsDNA antibodies were the influencing factors of LN in patients with SLE (P < 0.05); ALB, UC, and complement 3(C3) were the influencing factors of lupus disease activity (P < 0.05); UC, C3, and hemoglobin (HB) were the influencing factors of abnormal renal function in SLE patients. RESULTS: The results of the ROC curve showed that ALB, UA, and TC had certain predictive value for combined LN in patients with SLE, and the predictive value of ALB was greater than that of TC (P < 0.05); ALB, UA, and C3 being predictors of the activity of patients with SLE; BUN, UA, and HB all had certain predictive value for the abnormal renal function in patients with LN. SLE patients have the high incidence of renal impairment. CONCLUSION: The results of this study suggest that patients with SLE should regularly monitor the levels of ALB, UA, TC, C3, and HB, as well as pay attention to the intervention of hyperlipidemia and hyperuricemia in patients with SLE to better control disease progression.

Scavenger Receptor Class B Type I Deficiency Induces Iron Overload and Ferroptosis in Renal Tubular Epithelial Cells via Hypoxia-Inducible Factor-1α/Transferrin Receptor 1 Signaling Pathway.

Aims: Scavenger receptor class B type I (SRBI) promotes cell cholesterol efflux and the clearance of plasma cholesterol. Thus, SRBI deficiency causes abnormal cholesterol metabolism and hyperlipidemia. Studies have suggested that ferroptosis is involved in lipotoxicity; however, whether SRBI deficiency could induce ferroptosis remains to be investigated. Results: We knocked down or knocked out SRBI in renal HK-2 cells and C57BL/6 mice to determine the expression levels of ferroptosis-related regulators. Our results demonstrated that SRBI deficiency upregulates transferrin receptor 1 (TFR1) expression and downregulates ferroportin expression, which induces iron overload and subsequent ferroptosis in renal tubular epithelial cells. TFR1 is known to be regulated by hypoxia-inducible factor-1α (HIF-1α). Next, we investigated whether SRBI deletion affected HIF-1α. SRBI deletion upregulated the mRNA and protein expression of HIF-1α, and promoted its translocation to the nucleus. To determine whether HIF-1α plays a key role in SRBI-deficiency-induced ferroptosis, we used HIF-1α inhibitor and siHIF-1α in HK-2 cells, and found that downregulation of HIF-1α prevented SRBI-silencing-induced TFR1 upregulation and iron overload, and eventually reduced ferroptosis. The underlying mechanism of HIF-1α activation was explored next, and the results showed that SRBI knockout or knockdown may upregulate the expression of HIF-1α, and promote HIF-1α translocation from the cytoplasm into the nucleus via the PKC-ß/NF-κB signaling pathway. Innovation and Conclusion: Our study showed, for the first time, that SRBI deficiency induces iron overload and subsequent ferroptosis via the HIF-1α/TFR1 pathway.

The discovery of the subgenus Hysterobolus Viereck, 1913 (Hymenoptera, Braconidae, Brachistinae, Blacini, Blacus) in China, with description of nine new species.

The subgenus Hysterobolus Viereck, 1913 (Hymenoptera, Braconidae, Blacus) is newly recorded from China. Nine new species are proposed, B. (H.) baishanzuensis sp. nov., B. (H.) flaviceps sp. nov., B. (H.) laculaticornis sp. nov., B. (H.) longiapicalis sp. nov., B. (H.) melanoapicalis sp. nov., B. (H.) niger sp. nov., B. (H.) variegatus sp. nov., B. (H.) xui sp. nov., B. (H.) yunnanensis sp. nov., and one species, B. (H.) chabarovi Belokobylskij, 1995, is newly recorded from China. An updated key to the currently known species of the subgenus Hysterobolus in China is provided.

The discovery of the subgenus Contochorus van Achterberg, 1976 (Hymenoptera, Braconidae, Brachistinae, Blacini, Blacus) in China.

The subgenus Contochorus van Achterberg, 1976 (Hymenoptera, Braconidae, Blacus) is newly recorded from China. Two new species are proposed, B. (C). capillosus sp. nov., B. (C). planus sp. nov., and two species are newly recorded in China, B. (C). mellitarsis van Achterberg, 1988 and B. (C). turbidus Papp, 1985. An updated key to the currently known species of the subgenus Contochorus in the world is provided.

Empagliflozin attenuates the renal tubular ferroptosis in diabetic kidney disease through AMPK/NRF2 pathway.

Renal tubular damage plays a key role in the pathogenesis of diabetic kidney disease (DKD), and one of the main pathological process associated with DKD in diabetic mice is the ferroptosis, a novel form of cell death caused by iron-dependent lipid peroxidation. Several researches suggested that empagliflozin may treat renal injury, but its effects on diabetic-related ferroptosis and underlying mechanisms were not fully elucidated. In this study, the influence of empagliflozin on renal injury was evaluated in vivo and in vitro in a mouse model and in high-glucose (HG) or Erastin-stimulated renal HK-2 cell line, respectively. Ferroptosis-related markers were assessed, including GSH, labile iron levels, and ferroptosis regulators by Western blot, qRT-PCR, immunohistochemistry, and immunofluorescence. The level of malondialdehyde (MDA) and the fluorescence intensity of BODIPY probe indicated the level of lipid peroxidation. It was demonstrated that solute carrier family 7, member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) were less expressed in renal biopsy samples from patients affected by DKD than in those from non-diabetic renal disease patients (NDRD), proving the ferroptosis of tubular epithelial cells in case of DKD. Furthermore, empagliflozin markedly decreased the ferroptosis impairment in DKD mice, as well as in HG model of HK-2 cells. Our investigations showed the ability of empagliflozin to suppress ferroptosis was partially countered by AMP-activated protein kinase (AMPK) inhibitor, which led to a reduction of the nuclear translocation of the antioxidant transcription factor NFE2-related factor 2 (NRF2) and downregulation of target genes such as GPX4, ferritin heavy chain 1 (FTH1), and SLC7A11, while AMPK agonists were responsible for the enhancement of the protective effects of empagliflozin. Taken together, our findings showed that empagliflozin may prevent the development of ferroptosis by promoting the AMPK-mediated NRF2 activation pathway, providing important insights for possible novel treatment approaches for DKD.