Re-positioning of low dose paclitaxel against depressive-like behavior and neuroinflammation induced by lipopolysaccharide in rats: Crosstalk between NLRP3/caspase-1/IL-1ß and Sphk1/S1P/ NF-κB signaling pathways.

AIMS: Depression is a potentially fatal illness affecting millions of individuals worldwide, across all age groups. Neuroinflammation is a key factor in depression development. Paclitaxel (PXL), a well-known chemotherapeutic agent has been used as therapy for several types of cancer. This study aims to evaluate the ameliorative effect of low-dose PXL against lipopolysaccharide (LPS)-induced depression in rats. MATERIALS AND METHODS: Adult male Sprague-Dawley rats were administrated a single dose of LPS (5 mg/kg, i.p.); 2 h later, rats received PXL (0.3 mg/kg, i.p. three times/week) for one week. KEY FINDINGS: Low-dose PXL alleviated LPS-induced depressive-like behavior in rats as evidenced by significantly improving behavioral changes in both forced swim test (FST) and open field test (OFT), successfully mitigated depletion of monoamines (serotonin, norepinephrine, and dopamine), in addition to markedly decreasing lipid peroxidation with antioxidant levels elevation in brain tissues. Low-dose PXL substantially decreased inflammation triggered by LPS in brain tissue via repressing the expression of NLRP3 and its downstream markers level, caspase-1 and IL-1ß jointly with a corresponding decrease in proinflammatory cytokine levels (TNF-α). Furthermore, low-dose PXL remarkably down-regulated Sphk1/S1P signaling pathway. Concurrent with these biochemical findings, there was a noticeable improvement in the brain tissue's histological changes. SIGNIFICANCE: These findings prove the role of low-dose PXL in treatment of LPS-induced neuroinflammation and depressive-like behavior through their anti-depressant, antioxidant and anti-inflammatory actions. The suggested molecular mechanism may entail focusing the interconnection among Sphk1/S1P, and NLRP3/caspase-1/IL-1ß signaling pathways. Hence PXL could be used as a novel treatment against LPS-induced depression.

Chronotherapeutic neuroprotective effect of verapamil against lipopolysaccharide-induced neuroinflammation in mice through modulation of calcium-dependent genes.

BACKGROUND: Neuroinflammation is a major mechanism in neurodegenerative diseases such as Alzheimer's disease (AD), which is a major healthcare problem. Notwithstanding of ample researches figured out possible molecular mechanisms underlying the pathophysiology of AD, there is no definitive therapeutics that aid in neuroprotection. Therefore, searching for new agents and potential targets is a critical demand. We aimed to investigate the neuroprotective effect of verapamil (VRP) against lipopolysaccharide (LPS)-induced neuroinflammation in mice and whether the time of VRP administration could affect its efficacy. METHODS: Forty male albino mice were used and were divided into normal control, LPS only, morning VRP, and evening VRP. Y-maze and pole climbing test were performed as behavioral tests. Hematoxylin and eosin together with Bielschowsky silver staining were done to visualize neuroinflammation and phosphorylated tau protein (pTAU); respectively. Additionally, the state of mitochondria, the levels of microglia-activation markers, inflammatory cytokines, intracellular Ca2+, pTAU, and Ca2+-dependent genes involving Ca2+/ calmodulin dependent kinase II (CAMKII) isoforms, protein kinase A (PKA), cAMP response element-binding protein (CREB), and brain-derived neurotrophic factor (BDNF), with the level of VRP in the brain tissue were measured. RESULTS: LPS successfully induced neuroinflammation and hyperphosphorylation of tau protein, which was indicated by elevated levels of microglia markers, inflammatory cytokines, and intracellular Ca2+ with compromised mitochondria and downregulated CAMKII isoforms, PKA, CREB and BDNF. Pretreatment with VRP showed significant enhancement in the architecture of the brain and in the behavioral tests as indicated by the measured parameters. Moreover, morning VRP exhibited better neuroprotective profile compared to the evening therapy. CONCLUSIONS: VRP highlighted a multilevel of neuroprotection through anti-inflammatory activity, Ca2+ blockage, and regulation of Ca2+-dependent genes. Furthermore, chronotherapy of VRP administration should be consider to achieve best therapeutic efficacy.

Colchicine attenuates renal ischemia-reperfusion-induced liver damage: implication of TLR4/NF-κB, TGF-ß, and BAX and Bcl-2 gene expression.

Ischemia-reperfusion injury (IRI) is typically associated with a vigorous inflammatory and oxidative stress response to hypoxia and reperfusion that disturbs the function of the organ. The remote effects of renal IRI on the liver, however, require further study. Renal damage associated with liver disease is a common clinical problem. Colchicine, a polymerization inhibitor of microtubules, has been used as an anti-inflammatory and anti-fibrotic drug for liver diseases. The goal of the current study was to investigate the possible protective mechanisms of colchicine on liver injury following renal IRI. Forty rats were divided randomly into four groups: sham group, colchicine-treated group, IRI group, and colchicine-treated + IRI group. Treatment with colchicine significantly reduced hepatic toll-like receptor 4 (TLR4), nuclear factor kappa B (NF-κB) transcription factor, myeloid differentiation factor 88 (MyD88), and tumor necrosis factor-alpha (TNF-α) contents; downregulated BCL2 associated X apoptosis regulator (BAX) gene expression, transforming growth factor-ß (TGF-ß) content, and upregulated hepatic B cell lymphoma 2 (Bcl-2) gene expression as compared with the IRI group. Finally, hepatic histopathological examinations have confirmed the biochemical results. Renal IRI-induced liver damage in rats was alleviated by colchicine through its anti-inflammatory, anti-apoptotic, and anti-fibrotic actions.

The possible protective effect of colchicine against liver damage induced by renal ischemia-reperfusion injury: role of Nrf2 and NLRP3 inflammasome.

Ischemia-reperfusion injury (IRI) induces an inflammatory response and production of reactive oxygen species, which affects the organs remote to the sites of renal IR. However, remote effects of renal IRI on the liver need further investigations. Renal injury associated with liver disease is a common clinical problem. Colchicine is an established drug for microtubule stabilization that may reduce tissue injury and has antioxidant and antiinflammatory effects. The aim of the present study was (i) to assess the hepatic changes after induction of renal IRI, (ii) to explore the possible protective effect of colchicine on liver injury following renal IRI, and (iii) to investigate the possible mechanisms underlying the potential effect. Forty rats were randomly divided into four groups: sham operation group, colchicine-treated group, IR group, and colchicine-treated IR group. Colchicine treatment improved liver function (ALT/AST) after renal IRI, decreased hepatic oxidative stress and cell apoptosis by reducing hepatic MDA, upregulating hepatic total antioxidant capacity, Nrf2, and HO-1. Furthermore, colchicine inhibited inflammatory responses by downregulating hepatic NLRP3 inflammasome, IL-1ß, and caspase-1. Colchicine attenuates renal IRI-induced liver injury in rats. This effect may be due to reducing inflammation and oxidative stress markers.

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

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-1ß 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-1ß signalling pathways and modulating the Nrf2/HO-1 signalling pathway.

Protective effect of cardamonin against acetic acid-induced ulcerative colitis in rats.

BACKGROUND: Ulcerative colitis (UC) is an inflammatory bowel disease with significant morbidity. Cardamonin is a natural chalcone derivative with considerable anti-inflammatory activity. Herein, the potential protective effect of cardamonin against UC was tested in a rat model. METHODS: Rats were given 10 or 30mg/kg/day of cardamonin orally for 14days before induction of UC. On the 14th day of treatment, UC was induced by intrarectal instillation of 2ml 3% acetic acid. Twenty four h after acetic acid instillation, rats were sacrificed and colons were analyzed by macroscopic and histopathological examination. Colon lipid peroxidation was examined by biochemical evaluation of malondialdehyde (MDA). Myeloperoxidase (MPO), iNOS, NF-κB, TNFα levels were measured by ELISA. Moreover, caspase-3 and COX-2 were assessed by immunohistochemical analysis. RESULTS: Cardamonin at 10 and 30mg/kg decreased the disease activity index and macroscopic damage index scores, and significantly reduced histopathological deterioration. Additionally, cardamonin reduced levels of MPO, iNOS, NF-κB, TNFα and MDA (p<0.05). Immunohistochemistry revealed down-regulation of COX-2 and caspase-3 in groups treated with cardamonin. CONCLUSION: Cardamonin has a protective effect against acetic acid-induced colitis. This effect may be due to reducing inflammation, oxidative stress and apoptosis.