The selective COX-2 inhibitor Etoricoxib reduces acute inflammatory markers in a model of neurogenic laryngitis but loses its efficacy with prolonged treatment

Etoricoxib nanostructured lipid carriers attenuate inflammation by modulating Cyclooxygenase-2 signaling and activation of nuclear factor-κB-p65 pathways in radiation-induced acute cardiotoxicity in rats

The current investigation aimed to explore the potential of etoricoxib nanostructured lipid carriers (ET-NLCs) as an anti-inflammatory drug in radiation-exposed rats, with a focus on assessing its efficacy in reducing inflammation while minimizing cardiac toxicity compared to conventional etoricoxib (ET) treatment. The ET-NLCs were prepared by the low-temperature melt emulsification solidification technique. Various techniques were employed to characterize the NLCs. Rats were exposed to gamma-irradiation (6 Gy) to induce cardiac inflammation and injury, followed by oral administration of ET or ET-NLCs (10 mg/kg b.w.) for 14 consecutive days. Results demonstrated a significant increase in the levels of malondialdehyde (MDA), cyclooxygenase-2 (COX-2), nuclear factor kappa-B p65 (NF-κB-p65), and poly ADP-ribose polymerase (PARP-1) in the heart tissues of gamma-irradiated rats compared to the control group. This increase was accompanied by a reduction in the activity of antioxidant enzymes. However, treatment with ET and ET-NLCs exhibited a positive impact on these levels. Interestingly, the efficacy of ET-NLCs in mitigating radiation-induced inflammation in heart tissue was found to be superior to that of ET. In conclusion, the study suggests that the utilization of NLCs as a drug delivery system for ET may not only enhance its therapeutic efficacy but also help reduce the cardiovascular risks associated with ET, specifically focused on individuals who had been exposed to gamma radiation. These findings open new avenues for further research in the development of effective and safer therapeutic strategies for managing inflammatory diseases and their impact on cardiovascular health.

Etoricoxib inhibits peripheral inflammation and alters immune responses in intracerebroventricular colchicine injected rats

The present study was designed to investigate the effectiveness of etoricoxib induced inhibition of neuroinflammation by studying the peripheral inflammatory markers and select immune parameters in intracerebroventricular colchicine injected rats (ICIR). Results showed time dependent upregulation of the inflammatory markers in the serum along with alterations of peripheral immune parameters in ICIR and dose-dependent recovery was observed upon administration of etoricoxib to ICIR; most of these effects were greater with the longer duration of study. The present study indicates that colchicine induced neuroinflammation may cause systemic inflammation and alteration of immune responses which are mediated by increased cox- 2 activity.

Matairesinol Suppresses Neuroinflammation and Migration Associated with Src and ERK1/2-NF-κB Pathway in Activating BV2 Microglia

Chronic neuroinflammation is a pathological feature of neurodegenerative diseases. Inhibition of microglia-mediated neuroinflammation might be a potential strategy for neurodegeneration. Matairesinol, a dibenzylbutyrolactone plant lignan, presents in a wide variety of foodstuffs. It has been found to possess anti-angiogenic, anti-oxidative, anti-cancer and anti-fungal activities. In the present study, we investigated the anti-neuroinflammation effects of matairesinol on lipopolysaccharide (LPS)-induced BV2 microglia cells and the related molecular mechanisms. The results showed that matairesinol inhibited microglia activation by reducing the production of nitric oxide, the expression of inducible nitric oxide synthase and cyclooxygenase-2 in a concentration-dependent manner (6.25, 12.5, 25 μM). In the molecular signaling pathway, LPS-induced nuclear factor-kappa B (NF-κB) transcriptional activity and translocation into the nucleus were remarkably suppressed by matairesinol through the inhibition of the extracellular signal-regulated kinase (ERK)1/2 signal transduction pathways, but not p38 MAPK or c-jun N-terminal kinase (JNK). Meanwhile, matairesinol also blocked LPS-mediated microglia migration and this was associated with inhibition of LPS-induced Src phosphorylation as well as Src expression in a concentration-dependent manner. Taken together, these results suggest that matairesinol inhibited inflammatory response and migration in LPS-induced BV2 microglia, and the mechanisms may be associated with the NF-κB activation and modulation of Src pathway.

Cox-2 Plays a Vital Role in the Impaired Anxiety Like Behavior in Colchicine Induced Rat Model of Alzheimer Disease

The anxiety status is changed along with memory impairments in intracerebroventricular colchicine injected rat model of Alzheimer Disease (cAD) due to neurodegeneration, which has been indicated to be mediated by inflammation. Inducible cox-2, involved in inflammation, may have important role in the colchicine induced alteration of anxiety status. Therefore, the present study was designed to investigate the role of cox-2 on the anxiety behavior (response to novelty in an elevated open field space) of cAD by inhibiting it with three different doses (10, 20, and 30 mg) of etoricoxib (a cox-2 blocker) in two time points (14 and 21 days). The results showed anxiolytic behavior in cAD along with lower serum corticosterone level, both of which were recovered at all the doses of etoricoxib on day 21. On day 14 all of the anxiety parameters showed similar results to that of day 21 at high doses but not at 10 mg/kg body weight. Results indicate that the parameters of anxiety were dependent on neuronal circuitries that were probably sensitive to etoricoxib induced blocking of neurodegeneration. The present study showed that anxiolytic behavior in cADr is predominantly due to cox-2 mediated neuroinflammation induced neurodegeneration in the brain.

Role of cox-2 mediated neuroinflammation on the neurodegeneration and cognitive impairments in colchicine induced rat model of Alzheimer's Disease

The neurodegeneration in colchicine induced AD (cAD) rats is linked with neuroinflammation. The inducible cox-2 present in the brain may participate in the neuroinflammatory process related to progressive neurodegeneration in cAD rats. The aim of this study is to investigate the role of cox-2 in the neurodegeneration and cognitive impairments in cAD rats. The parameters of memory (working and reference memory), inflammatory markers [IL-1β, TNF-α, prostaglandin E2 (PGE2), cox-2 level] and histopathology of hippocampus were measured after 21-day of i.c.v. colchicine injection in rats and compared with that of control and sham operated rats. These parameters were also measured in these 3 different groups of rats after p.o. administration of 3 different doses of etoricoxib, a cox 2 inhibitor. The impairments of working and reference memory were associated with neuroinflammation and neurodegeneration in the hippocampus and increased cox-2 and PGE2 levels in hippocampus in cAD. Administration of etoricoxib in cAD rats resulted in recovery of memory impairments, neurodegeneration and neuroinflammation in hippocampus and inhibition of cox-2 and PGE2 levels in hippocampus. It appears from the results that activation of cox-2 in cAD is related to neuroinflammation involved in neurodegeneration. Colchicine induced initial neurodegeneration may trigger cascade of events for a progressive neurodegeneration where cox-2 activation plays a critical role. Moreover, this cox-2 mediated neurodegeneration is related to impairments of memory parameters. Thus, the present study showed that the impairments of memory and neurodegeneration in the hippocampus of cAD in 21-day study are mediated by cox-2 induced neuroinflammation.

Potentiated anti-inflammatory effect of combined 780 nm and 660 nm low level laser therapy on the experimental laryngitis

Reflux laryngitis is a common clinic complication of nasogastric intubation (NSGI). Since there is no report concerning the effects of low level laser therapy (LLLT) on reflux laryngitis, this study aimed to analyze the protective effect of single and combined therapies with low level laser at the doses of 2.1J and 2.1+1.2 J with a total irradiation time of 30s and 30+30 s, respectively, on a model of neurogenic reflux laryngitis. NSGI was performed in Wistar rats, assigned into groups: NGI (no treatment), NLT17.5 (single therapy), and NLT17.5/10.0 (combined therapy, applied sequentially). Additional non-intubated and non-irradiated rats were use as controls (CTR). Myeloperoxidase (MPO) activity was assessed by colorimetric method after the intubation period (on days 1, 3, 5, and 7), whereas paraffin-embedded laryngeal specimens were used to carry out histopathological analysis of the inflammatory response, granulation tissue, and collagen deposition 7 days after NSGI. Significant reduction in MPO activity (p<0.05) and in the severity of the inflammatory response (p<0.05), and improvement in the granulation tissue (p<0.05) was observed in NLT17.5/10.0 group. Mast cells count was significantly decreased in NGI and NLT17.5 groups (p<0.001), whereas no difference was observed between NLT17.5/10.0 and CTR groups (p>0.05). NLT17.5/10.0 group also showed better collagenization pattern, in comparison to NGI and NLT17.5 groups. This study suggests that the combined therapy successfully modulated the inflammatory response and collagenization in experimental model of NSGI-induced neurogenic laryngitis.