BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(X...BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(XIST)expression has been reported to be elevated in the serum of DN patients.AIM To evaluate the mechanism of lncRNA XIST in renal tubular epithelial cell(RTEC)pyroptosis in DN.METHODS A DN rat model was established through streptozotocin injection,and XIST was knocked down by tail vein injection of the lentivirus LV sh-XIST.Renal metabolic and biochemical indices were detected,and pathological changes in the renal tissue were assessed.The expression of indicators related to inflammation and pyroptosis was also detected.High glucose(HG)was used to treat HK2 cells,and cell viability and lactate dehydrogenase(LDH)activity were detected after silencing XIST.The subcellular localization and downstream mechanism of XIST were investigated.Finally,a rescue experiment was carried out to verify that XIST regulates NLR family pyrin domain containing 3(NLRP3)/caspase-1-mediated RTEC pyroptosis through the microRNA-15-5p(miR-15b-5p)/Toll-like receptor 4(TLR4)axis.RESULTS XIST was highly expressed in the DN models.XIST silencing improved renal metabolism and biochemical indices and mitigated renal injury.The expression of inflammation and pyroptosis indicators was significantly increased in DN rats and HG-treated HK2 cells;cell viability was decreased and LDH activity was increased after HGtreatment. Silencing XIST inhibited RTEC pyroptosis by inhibiting NLRP3/caspase-1. Mechanistically,XIST sponged miR-15b-5p to regulate TLR4. Silencing XIST inhibited TLR4 by promotingmiR-15b-5p. miR-15b-5p inhibition or TLR4 overexpression averted the inhibitory effect ofsilencing XIST on HG-induced RTEC pyroptosis.CONCLUSIONSilencing XIST inhibits TLR4 by upregulating miR-15b-5p and ultimately inhibits renal injury inDN by inhibiting NLRP3/caspase-1-mediated RTEC pyroptosis.展开更多
Background： Cryopyrin-associated periodic syndrome （CAPS） is a group of rare, heterogeneous autoinflammatory disease characterized by interleukin （IL）-1β-mediated systemic inflammation and clinical symptoms invo...Background： Cryopyrin-associated periodic syndrome （CAPS） is a group of rare, heterogeneous autoinflammatory disease characterized by interleukin （IL）-1β-mediated systemic inflammation and clinical symptoms involving skin, joints, central nervous system, and eyes. It encompasses a spectrum of three clinically overlapping autoinflammatory syndromes including familial cold autoinflammatory syndrome, Muckle-Wells syndrome （MWS）, and neonatal-onset multisystem inflammatory disease. CAPS is associated with gain-of-function missense mutations in NOD-like receptor family pyrin domain-containing protein 3 （NLRP3）, the gene encoding NLRP3. Moreover, most mutations leading to MWS occurred in exon 3 ofNLRP3 gene. Here, we reported a novel mutation occurred in exon 1 ofNLRP3 gene in an MWS patient and attempted to explore the pathogenic mechanism. Methods： Genetic sequence analysis of NLRP3 was performed in an MWS patient who presented with periodic lever, arthralgia, and multiform skin lesions. NLRP3 was also analyzed in this patient＇s parents and 50 healthy individuals. Clinical examinations including X-ray examination, skin biopsy, bone marrow aspiration smear, and blood test of C-reactive protein （CRP）, erythrocyte sedimentation rate （ESR）, serum levels oflL-1β, immunoglobulin E （lgE）, antineutrophil cytoplasmic antibodies, antinuclear antibodies, and extractable nuclear antigen were also analyzed. The protein structure of mutant NLRP3 inflammasome was calculated by SWISS-MODEL software. Proteins of wild type and mutant components ofNLRP3 inflammasome were expressed and purified, and the interaction abilities between these proteins were tested by surface plasmon resonance （SPR） assay. Results： X-ray examination showed no abnormality in the patient＇s knees. Laboratory tests indicated an elevation of CRP （233.24 nag/L） and ESR （67 mm/h） when the patient had fever. Serum IL-1β increased to 24.37 pg/ml, and serum lgE was higher than 2500.00 IU/ml. Other blood tests were normal. Bone marrow aspiration smear was normal. A novel point mutation c.92A〉T in exon 1 of NLRP3 gene was identified, which caused a p.D31V mutation in pyrin domain （PYD） of NLRP3. SPR assay showed that this point mutation may strengthen the interaction between the PYD of NLRP3 and the PYD of the apoptosis-associated speck-like protein. The mutation c.92A〉T in exon 1 of the NLRP3 gene was not lbund in the patient＇s parents and 50 healthy individuals. Conclusions： The rnutation c.92A〉T in exon 1 of the NLRP3 gene is a novel mutation associated with MWS. The p.D31V mutation might promote the activation ofNLRP3 inflammasome and induce MWS in this patient.展开更多
基金Supported by Natural Science Foundation of Shenzhen University General Hospital (SUGH2020QD011)
文摘BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(XIST)expression has been reported to be elevated in the serum of DN patients.AIM To evaluate the mechanism of lncRNA XIST in renal tubular epithelial cell(RTEC)pyroptosis in DN.METHODS A DN rat model was established through streptozotocin injection,and XIST was knocked down by tail vein injection of the lentivirus LV sh-XIST.Renal metabolic and biochemical indices were detected,and pathological changes in the renal tissue were assessed.The expression of indicators related to inflammation and pyroptosis was also detected.High glucose(HG)was used to treat HK2 cells,and cell viability and lactate dehydrogenase(LDH)activity were detected after silencing XIST.The subcellular localization and downstream mechanism of XIST were investigated.Finally,a rescue experiment was carried out to verify that XIST regulates NLR family pyrin domain containing 3(NLRP3)/caspase-1-mediated RTEC pyroptosis through the microRNA-15-5p(miR-15b-5p)/Toll-like receptor 4(TLR4)axis.RESULTS XIST was highly expressed in the DN models.XIST silencing improved renal metabolism and biochemical indices and mitigated renal injury.The expression of inflammation and pyroptosis indicators was significantly increased in DN rats and HG-treated HK2 cells;cell viability was decreased and LDH activity was increased after HGtreatment. Silencing XIST inhibited RTEC pyroptosis by inhibiting NLRP3/caspase-1. Mechanistically,XIST sponged miR-15b-5p to regulate TLR4. Silencing XIST inhibited TLR4 by promotingmiR-15b-5p. miR-15b-5p inhibition or TLR4 overexpression averted the inhibitory effect ofsilencing XIST on HG-induced RTEC pyroptosis.CONCLUSIONSilencing XIST inhibits TLR4 by upregulating miR-15b-5p and ultimately inhibits renal injury inDN by inhibiting NLRP3/caspase-1-mediated RTEC pyroptosis.
基金This work was supported by the grant from the National Natural Science Foundation of China （No. 81201267）.
文摘Background： Cryopyrin-associated periodic syndrome （CAPS） is a group of rare, heterogeneous autoinflammatory disease characterized by interleukin （IL）-1β-mediated systemic inflammation and clinical symptoms involving skin, joints, central nervous system, and eyes. It encompasses a spectrum of three clinically overlapping autoinflammatory syndromes including familial cold autoinflammatory syndrome, Muckle-Wells syndrome （MWS）, and neonatal-onset multisystem inflammatory disease. CAPS is associated with gain-of-function missense mutations in NOD-like receptor family pyrin domain-containing protein 3 （NLRP3）, the gene encoding NLRP3. Moreover, most mutations leading to MWS occurred in exon 3 ofNLRP3 gene. Here, we reported a novel mutation occurred in exon 1 ofNLRP3 gene in an MWS patient and attempted to explore the pathogenic mechanism. Methods： Genetic sequence analysis of NLRP3 was performed in an MWS patient who presented with periodic lever, arthralgia, and multiform skin lesions. NLRP3 was also analyzed in this patient＇s parents and 50 healthy individuals. Clinical examinations including X-ray examination, skin biopsy, bone marrow aspiration smear, and blood test of C-reactive protein （CRP）, erythrocyte sedimentation rate （ESR）, serum levels oflL-1β, immunoglobulin E （lgE）, antineutrophil cytoplasmic antibodies, antinuclear antibodies, and extractable nuclear antigen were also analyzed. The protein structure of mutant NLRP3 inflammasome was calculated by SWISS-MODEL software. Proteins of wild type and mutant components ofNLRP3 inflammasome were expressed and purified, and the interaction abilities between these proteins were tested by surface plasmon resonance （SPR） assay. Results： X-ray examination showed no abnormality in the patient＇s knees. Laboratory tests indicated an elevation of CRP （233.24 nag/L） and ESR （67 mm/h） when the patient had fever. Serum IL-1β increased to 24.37 pg/ml, and serum lgE was higher than 2500.00 IU/ml. Other blood tests were normal. Bone marrow aspiration smear was normal. A novel point mutation c.92A〉T in exon 1 of NLRP3 gene was identified, which caused a p.D31V mutation in pyrin domain （PYD） of NLRP3. SPR assay showed that this point mutation may strengthen the interaction between the PYD of NLRP3 and the PYD of the apoptosis-associated speck-like protein. The mutation c.92A〉T in exon 1 of the NLRP3 gene was not lbund in the patient＇s parents and 50 healthy individuals. Conclusions： The rnutation c.92A〉T in exon 1 of the NLRP3 gene is a novel mutation associated with MWS. The p.D31V mutation might promote the activation ofNLRP3 inflammasome and induce MWS in this patient.
