Reduction of carrageenan-induced acute pulmonary inflammation in mice by novel thiazolidinedione derivative LPSF/RA-4

Immune cells crosstalk Pathways, and metabolic alterations in Idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) presents a challenging progression characterized by lung tissue scarring and abnormal extracellular matrix deposition. This review examines the influence of immune responses, emphasizing their complex role in initiating and perpetuating fibrosis. It highlights how metabolic pathways modulate immune cell function during IPF. Immune cell modulation holds promise in managing pulmonary fibrosis (PF). Inhibiting neutrophil recruitment and monitoring mast cell levels offer insights into PF progression. Low-dose IL-2 therapy and regulation of fibroblast recruitment present potential therapeutic avenues, while the role of innate lymphoid cells (ILC2s) in allergic lung inflammation sheds light on disease mechanisms. The review focuses on metabolic reprogramming's role in shaping immune cell function during IPF progression. While some immune cells use glycolysis for pro-inflammatory responses, others favor fatty acid oxidation for regulatory functions. Targeting specialized pro-resolving lipid mediators (SPMs) presents significant potential for managing fibrotic disorders. Additionally, it highlights the pivotal role of amino acid metabolism in synthesizing serine and glycine as crucial regulators of collagen production and exploring the interconnectedness of lipid metabolism, mitochondrial dysfunction, and adipokines in driving fibrotic processes. Moreover, the review discusses the impact of metabolic disorders such as obesity and diabetes on lung fibrosis. Advocating for a holistic approach, it emphasizes the importance of considering this interplay between immune cell function and metabolic pathways in developing effective and personalized treatments for IPF.

Inhibitory effect of hydroalcoholic extract of Cunila spicata Benth. on phlogistic agents-induced cellular migration in the airways of mice

ETHNOPHARMACOLOGICAL RELEVANCE

Cunila spicata Benth. Is a creeping and aromatic plant that has an ethnopharmacological indication in the southern region of Brazil, in the Araucaria Forest biome. It's used as an alternative therapy for respiratory diseases for men and animals since the "tropeirista" movement in colonial Brazil.

AIM OF THE STUDY

Investigate the influence of oral administration of hydroalcoholic extract of C. spicata (HECS) on cellular inflammatory processes in the airways of mice.

MATERIAL AND METHODS

The HECS was obtained by the ultrasound-assisted technique. Phytochemical analysis of the volatile compounds was performed using gas-chromatography with mass spectrometry. To investigate the biological activity of HECS, the animals were pre-treated with HECS orally 1 h before and the bronchoalveolar lavage (BAL) model was used, in which the animals were subjected to inhalation of different pro-inflammatory agents such as carrageenan (CAR), histamine (HIST), capsaicin (CAP), bradykinin (BK), and 48/80 compound (C48/80). After sacrifice, BAL sample was collected from the bronchi and was analyzed for total and differential white blood cell counts, compared with control groups.

RESULTS

Fourteen volatile phytocompounds were identified in the HECS, the main ones being 2-bornanone, menthofuran and camphene. Among the HECS treated animals, all showed significant maximal inhibition (MI) when challenged with pro-inflammatory agents by nebulization. In the group of animals that received CAR, the MI was 72.77 ± 3.88%, compared to the negative control (NC). There was a predominance of lymphocytes (59.18 ± 4.07%). For the HIST group, MI was 64.03 ± 4.33%, in relation to the NC, with predominance in macrophages number (76.53 ± 2.78%). In the CAP group, the MI obtained was 38.90 ± 11.31%, with greater macrophage migration occurring (80.98 ± 3.44%) in the higher dose. For animals subjected to BK inhalation, the MI was 48.63 ± 3.95% with macrophages predominance (64.33 ± 10.04%). In the group that received C48/80 inhalation, the MI was 40.25 ± 5.30% (100 mg kg^-1), with higher occurrence of macrophages (72.97 ± 4.23%).

CONCLUSION

Our results suggest that HECS had a non-specific inhibitory effect on cellular migration induced by different pro-inflammatory agents, reducing inflammation in airways of mice. These effects coincide and support its ethnopharmacological use as an alternative medicine for respiratory diseases in regions where the plant is prevalent.

Anti-inflammatory activity of novel thiosemicarbazone compounds indole-based as COX inhibitors

BACKGROUND

In this article, a series of 20 new thiosemicarbazone derivatives containing indole were synthesized and evaluated for their anti-inflammatory potential.

METHODS

The compounds were obtained through a synthetic route of only two steps, with yields that varied between 33.6 and 90.4%, and characterized by spectroscopic and spectrometric techniques.

RESULTS

An initial screening through the lymphoproliferation assay revealed that compounds LT76, LT81, and LT87 were able to inhibit lymphocyte proliferation, with CC₅₀ of 0.56 ± 0.036, 0.9 ± 0.01 and 0.5 ± 0.07 µM, respectively, better results than indomethacin (CC₅₀ > 12 µM). In addition, these compounds were able to suppress the in-vitro production of TNF-α and NO, in addition to stimulating the production of IL-4. Reinforcing in-vitro assays, the compounds were able to inhibit COX-2 similar to Celecoxib showing greater selectivity for this isoform (LT81 SI: 23.06 versus Celecoxib SI: 11.88). Animal studies showed that compounds LT76 (64.8% inhibition after 6 h), LT81 (89% inhibition after 6 h) and LT87 (100% inhibition after 4 h) were able to suppress edema in mice after inoculation carrageenan with greater potency than indomethacin, and immunohistochemistry revealed that the groups treated with LT76, LT81 and LT87 reduced the expression of COX-2, similar or better results when compared to indomethacin. Complementarily, in-silico studies have shown that these compounds have a good pharmacokinetic profile, for respecting the parameters of Lipinski and Veber, showing their good bioavailability.

CONCLUSIONS

These results demonstrate the potency of thiosemicarbazone derivatives containing indole and confirm their importance as scaffolds of molecules with notorious anti-inflammatory activity.

Synthesis, in vitro and in vivo biological evaluation, COX-1/2 inhibition and molecular docking study of indole-N-acylhydrazone derivatives

The objective of this work was to obtain and evaluate anti-inflammatory in vitro, in vivo and in silico potential of novel indole-N-acylhydrazone derivatives. In total, 10 new compounds (3a-j) were synthesized in satisfactory yields, through a condensation reaction in a single synthesis step. In the lymphoproliferation assay, using mice splenocytes, 3a and 3b showed inhibition of lymphocyte proliferation of 62.7% (±3.5) and 50.7% (±2), respectively, while dexamethasone presented an inhibition of 74.6% (±2.4). Moreover, compound 3b induced higher Th2 cytokines production in mice splenocytes cultures. The results for COX inhibition assays showed that compound 3b is a selective COX-2 inhibitor, but with less potency when compared to celecoxib, and compound 3a not presented selectivity towards COX-2. The molecular docking results suggest compounds 3a and 3b interact with the active site of COX-2 in similar conformations, but not with the active site of COX-1, and this may be the main reason to the COX-2 selectivity of compound 3b. In vivo carrageenan-induced paw edema assays were adopted for the confirmation of the anti-inflammatory activity. Compound 3b showed better results in suppressing edema at all tested concentrations and was able to induce an edema inhibition of 100% after 5 h of carrageenan injection at the 30 mg kg^-1 dosage, corroborating with the COX inhibition and lymphoproliferation results. I addition to our experimental results, in silico analysis suggest that compounds 3a and 3b present a well-balanced profile between pharmacodynamics and pharmacokinetics. Thus, our preliminary results revealed the potentiality of a new COX-2 selective derivative in the modulation of the inflammatory process.

Diethylcarbamazine inhibits NF-κB activation in acute lung injury induced by carrageenan in mice

Diethylcarbamazine citrate (DEC) is widely used to treat lymphatic filariasis and Tropical Pulmonary Eosinophilia. A number of studies have reported a possible role in the host immune system, but exactly how DEC exerts this effect is still unknown. The present study reports the effects of DEC pretreatment on NF-κB regulation using the pleurisy model induced by carrageenan. Swiss male mice (Mus musculus) were divided into four experimental groups: control (SAL); carrageenan (CAR); diethylcarbamazine (DEC) and curcumin (CUR). The animals were pretreated with DEC (50mg/kg, v.o), CUR (50mg/kg, i.p) or distilled water for three consecutive days before pleurisy. One way analysis of variance (ANOVA) was performed by Tukey post-hoc test, and values were considered statistically significant when p<0.05. DEC pretreatment reduced tissue damage and the production of inflammatory markers, such as NO, iNOS, PGE2, COX-2, and PARP induced by carrageenan. Similarly, a known inhibitor of NF-κB pathway (curcumin) was also able to reduce these parameters. Like curcumin, DEC prevents NF-κB activation by reducing NF-κB p65 phosphorylation and IκBα degradation. DEC prevented NF-κB activation via p38 MAPK, but did not interfere in the ERK pathway in this experimental model. However, further studies should be developed to confirm this hypothesis. These findings suggest that DEC could be a promising drug for inflammatory disorders, especially in pulmonary diseases such as Acute Lung Inflammation, due its high anti-inflammatory potential which prevents NF-κB activation.

Diethylcarbamazine attenuates the development of carrageenan-induced lung injury in mice

Diethylcarbamazine (DEC) is an antifilarial drug with potent anti-inflammatory properties as a result of its interference with the metabolism of arachidonic acid. The aim of the present study was to evaluate the anti-inflammatory activity of DEC in a mouse model of acute inflammation (carrageenan-induced pleurisy). The injection of carrageenan into the pleural cavity induced the accumulation of fluid containing a large number of polymorphonuclear cells (PMNs) as well as infiltration of PMNs in lung tissues and increased production of nitrite and tumor necrosis factor-α and increased expression of interleukin-1β, cyclooxygenase (COX-2), and inducible nitric oxide synthase. Carrageenan also induced the expression of nuclear factor-κB. The oral administration of DEC (50 mg/Kg) three days prior to the carrageenan challenge led to a significant reduction in all inflammation markers. The present findings demonstrate that DEC is a potential drug for the treatment of acute lung inflammation.