Pramipexole and Lactoferrin ameliorate Cyclophosphamide-Induced haemorrhagic cystitis via targeting Sphk1/S1P/MAPK, TLR-4/NF-κB, and NLRP3/caspase-1/IL-1β signalling pathways and modulating the Nrf2/HO-1 pathway

Abstract

Background: The use of cyclophosphamide (CP) as a chemotherapeutic agent is limited by its major complication haemorrhagic cystitis (HC). Finding preventive, safe, and efficient treatments for such problems is extensively ongoing.

Objective: This research aims to assess the uroprotective effect of pramipexole (PPX) and/or lactoferrin (LF) against CP-induced HC, in addition to shedding light on their possible molecular targets.

Methods: Adult male Sprague-Dawley rats were orally administered PPX (3 mg/kg) and/or LF (300 mg/kg) for seven consecutive days, followed by a single intraperitoneal injection of CP (150 mg/kg).

Results: Pretreatment of CP-intoxicated rats with either PPX or LF mitigated oxidative urinary bladder damage via upregulation of the Nrf2/HO-1 signalling pathway, resulting in a significant reduction in bladder MDA and 8-OHdG levels with concomitant elevations in SOD activity and GSH content. Simultaneously, both drugs markedly halted inflammation in bladder tissue through inhibition of the TLR4/NF-κB signalling pathway, followed by a significant decrease in inflammatory cytokine levels (TNF-α and IL-6). Interestingly, the PPX/LF protocol downregulated p-p38, p-ERK1/2, Sphk1, and S1P protein expression and inhibited the NLRP3/caspase1/IL-1β axis. PPX/LF also significantly reduced BAX and caspase-3, in addition to increasing Bcl-2 levels in bladder tissue of CP-treated animals. These biochemical findings were supported by the improvement in the histological alterations induced by CP in the urinary bladder.

Conclusions: The current study verified the protective effect of PPX and LF against CP-induced HC by halting oxidative stress, inflammation, and apoptosis. The molecular mechanism underlying this protective effect may involve targeting the crosstalk among Sphk1/S1P/MAPK/NF-κB, TLR-4/NF-κB, and NLRP3/caspase-1/IL-1β signalling pathways and modulating the Nrf2/HO-1 signalling pathway.

Keywords: Cyclophosphamide; Haemorrhagic cystitis; MAPK; NLRP3; Nrf2; S1P.