Mitigation of nicotine-induced podocyte injury through inhibition of thioredoxin interacting protein.
Study Goal
The researchers aimed to determine whether TXNIP mediates nicotine-induced NLRP3 inflammasome activation and subsequent podocyte injury.
Results Summary
Nicotine treatment increased TXNIP/NLRP3 interaction, inflammasome activation, and podocyte damage, which was attenuated by TXNIP inhibitors Vera or SRI. The study demonstrated nicotine's harmful effects on podocytes, including increased apoptosis, cell permeability, and reduced podocin and nephrin expression.
Population
Podocytes (in vitro study)
Effective Dosage
Not specified
Duration
Not specified
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
nicotine | increase | TXNIP/NLRP3 interaction in podocytes | podocytes | - | induced | #1 |
pre-treatment with TXNIP inhibitors, verapamil (Vera) or SRI-37330 (SRI) | decrease | nicotine-induced TXNIP/NLRP3 interaction | podocytes | - | attenuates | #2 |
nicotine treatment | increase | colocalization of Nlrp3 with Asc | podocytes | - | significantly increased | #3 |
nicotine treatment | increase | colocalization of Nlrp3 with caspase-1 | podocytes | - | significantly increased | #4 |
nicotine treatment | increase | colocalization of Nlrp3 with TXNIP | podocytes | - | significantly increased | #5 |
Pretreatment with TXNIP inhibitor Vera or SRI | decrease | nicotine-induced Nlrp3/Asc colocalization | podocytes | - | abolished | #6 |
Pretreatment with TXNIP inhibitor Vera or SRI | decrease | nicotine-induced Nlrp3/caspase-1 colocalization | podocytes | - | abolished | #7 |
Pretreatment with TXNIP inhibitor Vera or SRI | decrease | nicotine-induced Nlrp3/TXNIP colocalization | podocytes | - | abolished | #8 |
nicotine treatment | increase | caspase-1 activity | podocytes | - | significantly increased | #9 |
nicotine treatment | increase | IL-1β production | podocytes | - | significantly increased | #10 |
prior treatment with TXNIP inhibiting Vera or SRI | decrease | nicotine-induced caspase-1 activity | podocytes | - | significantly attenuated | #11 |
prior treatment with TXNIP inhibiting Vera or SRI | decrease | nicotine-induced IL-1β production | podocytes | - | significantly attenuated | #12 |
nicotine treatment | decrease | podocin expression | podocytes | - | significantly decreased | #13 |
nicotine treatment | decrease | nephrin expression | podocytes | - | significantly decreased | #14 |
pretreatment with TXNIP inhibiting Vera or SRI | decrease | nicotine-induced podocin reduction | podocytes | - | attenuated | #15 |
pretreatment with TXNIP inhibiting Vera or SRI | decrease | nicotine-induced nephrin reduction | podocytes | - | attenuated | #16 |
nicotine treatment | increase | desmin expression | podocytes | - | significantly increased | #17 |
nicotine treatment | increase | apoptosis | podocytes | - | significantly increased | #18 |
nicotine treatment | increase | cell permeability | podocytes | - | significantly increased | #19 |
prior treatment with TXNIP inhibiting Vera or SRI | decrease | nicotine-induced desmin expression | podocytes | - | significantly attenuated | #20 |
prior treatment with TXNIP inhibiting Vera or SRI | decrease | nicotine-induced apoptosis | podocytes | - | significantly attenuated | #21 |
prior treatment with TXNIP inhibiting Vera or SRI | decrease | nicotine-induced cell permeability | podocytes | - | significantly attenuated | #22 |
Nicotine has been reported to initiate NLRP3 inflammasome formation and activation in different pathological conditions. The current study assessed whether thioredoxin-interacting protein (TXNIP) mediates nicotine-induced NLRP3 inflammasome activation and consequent podocyte injury. Co-immunoprecipitation analysis demonstrated that nicotine-induced TXNIP/NLRP3 interaction in podocytes relative to control groups. However, pre-treatment with TXNIP inhibitors, verapamil (Vera) or SRI-37330 (SRI) attenuates nicotine-induced TXNIP/NLRP3 interaction. Confocal microscopic analysis showed that nicotine treatment significantly increased the colocalization of Nlrp3 with Asc, Nlrp3 with caspase-1 and Nlrp3 with TXNIP in podocytes compared to control cells. Pretreatment with TXNIP inhibitor Vera or SRI abolished nicotine-induced Nlrp3/Asc, Nlrp3/caspase-1 or Nlrp3/TXNIP colocalization. Correspondingly, nicotine treatment significantly increased the caspase-1 activity and IL-1β production compared to control cells. However, prior treatment with TXNIP inhibiting Vera or SRI significantly attenuated the nicotine-induced caspase-1 activity and IL-1β production. Further immunofluorescence analysis showed that nicotine treatment significantly decreased podocin and nephrin expression compared to control cells. However, pretreatment with TXNIP inhibiting Vera or SRI attenuated the nicotine-induced podocin and nephrin reduction. In addition, confocal, flow cytometry and biochemical analysis showed that nicotine treatment significantly increased desmin expression, apoptosis and cell permeability compared to control cells. However, prior treatment with TXNIP inhibiting Vera or SRI significantly attenuated the nicotine-induced desmin expression, apoptosis and cell permeability. Taken together, our results demonstrate that TXNIP/NLRP3 interaction constitutes a potentially key signalling mechanism driving nicotine-induced NLRP3 inflammasome formation, activation and subsequent podocyte damage.