Avanafil as a Novel Therapeutic Agent Against LPS-Induced Acute Lung Injury via Increasing CGMP to Downregulate the TLR4-NF-κB-NLRP3 Inflammasome Signaling Pathway

Targeting Aquaporin-5 by Phosphodiesterase 4 Inhibition Offers New Therapeutic Opportunities for Ovarian Ischemia Reperfusion Injury in Rats

This study aimed to examine the effect of Phosphodiesterase 4 (PDE4) inhibition on Aquaporin-5 (AQP5) and its potential cell signaling pathway in the ovarian ischemia reperfusion (OIR) model. Thirty adult female rats were divided into five groups: Group 1; Control: Sham operation, Group 2; OIR that 3 hour ischemia followed by 3 hour reperfusion, Group 3; OIR + Rolipram 1 mg/kg, Group 4; OIR + Rolipram 3 mg/kg, Group 5; OIR + Rolipram 5 mg/kg. Rolipram was administered intraperitoneally to the rats in groups 3-4 and 5 at determined doses 30 minutes before reperfusion. From ovary tissue; Tumor necrosis factor-a (TNF-α), Cyclic adenosine monophosphate (cAMP), Nuclear factor kappa (NF-κB), Interleukin-6 (IL-6), Phosphodiesterase 4D (PDE4D), Mitogen-activated protein kinase (MAPK) and AQP5 levels were measured by ELISA. We also measured the level of AQP5 in ovary tissue by real-time reverse-transcription polymerase chain reaction (RT-PCR). In the OIR groups; TNF-α, NF-κB, IL-6, MAPK inflammatory levels increased, and cAMP and AQP5 levels decreased, which improved with the administration of rolipram doses. Also histopathological results showed damaged ovarian tissue after OIR, while rolipram administration decrased tissue damage in a dose dependent manner. We propose that the protective effect of PDE4 inhibition in OIR may be regulated by AQP5 and its potential cell signaling pathway and may be a new target in OIR therapy. However, clinical studies are needed to appraise these data in humans.

Fortunellin ameliorates LPS-induced acute lung injury, inflammation, and collagen deposition by restraining the TLR4/NF-κB/NLRP3 pathway

OBJECTIVE

Acute lung injury (ALI) is the prevalent respiratory disease of acute inflammation with high morbidity and mortality. Fortunellin has anti-inflammation property, but its role in ALI remains elusive. Thus, this study clarified the function of fortunellin on ALI pathogenesis.

METHODS

The ALI mouse model was established by lipopolysaccharide (LPS) induction, and lung tissue damage was evaluated utilizing hematoxylin-eosin (HE) staining. The edema of lung tissue was measured by the lung wet/dry (W/D) ratio. The lung capillary permeability was reflected by the protein content in bronchoalveolar lavage fluid (BALF). Inflammatory cell infiltration was measured by the evaluation of the content of myeloperoxidase (MPO), neutrophils, and leukocytes in BALF. Cell apoptosis was measured by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The secretions of inflammatory cytokines were quantified using enzyme-linked immunosorbent assay (ELISA) assays. Lung tissue collagen deposition was evaluated by Masson staining.

RESULTS

Fortunellin attenuated LPS-induced lung tissue damage and reduced the W/D ratio, the content of MPO in lung tissue, the total protein contents in BALF, and the neutrophils and leukocytes number. Besides, fortunellin alleviated LPS-stimulated lung tissue apoptosis, inflammatory response, and collagen deposition. Furthermore, Fortunellin repressed the activity of the Toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB)/NLR Family Pyrin Domain Containing 3 (NLRP3) pathway in the LPS-stimulated ALI model and LPS-induced RAW264.7 cells. Moreover, fortunellin attenuated LPS-stimulated tissue injury, apoptosis, inflammation, and collagen deposition of the lung via restraining the TLR4/NF-κB/NLRP3 pathway.

CONCLUSION

Fortunellin attenuated LPS-stimulated ALI through repressing the TLR4/NF-κB/NLRP3 pathway. Fortunellin may be a valuable drug for ALI therapy.

Effect of TLR3/dsRNA complex inhibitor on Poly(I:C)-induced airway inflammation in Swiss albino mice

Rhinovirus infection frequently causes COPD and asthma exacerbations. Impaired anti-viral signaling and reduced viral clearance have both been seen in sick bronchial epithelium, potentially increasing exacerbations. Polyinosinic:polycytidylic acid (Poly(I:C)), a Toll-like receptor-3 (TLR3) ligand, has been shown to cause a viral exacerbation of severe asthma by detecting double-stranded RNA (dsRNA). The purpose of this work was to determine the effect of a TLR3/dsRNA complex inhibitor-Calbiochem drug in the prevention of Poly(I:C)-induced airway inflammation following TLR3 activation and to uncover a potential pathway for the cure of asthma through TLR3 inhibition. Mice were sensitized with Poly(I:C) as an asthma model before being challenged by PBS and ovalbumin (OVA) chemicals. The mice were administered a TLR3/dsRNA complex inhibitor. Throughout the trial, the mice's body weight was measured after each dosage. Biochemical methods are used to analyze the protein as well as enzyme composition in airway tissues. BALF specimens are stained using Giemsa to identify inflammatory cells and lung histopathology to determine morphological abnormalities in lung tissues. By using the ELISA approach, cytokine levels such as TNF-α, IL-13, IL-6, IL-5, and IgE antibody expression in lung tissue and blood serum were assessed. TLR3/dsRNA complex inhibitor drug significantly lowered the number of cells in BALF and also on Giemsa staining slides. It also downregulated the level of TNF-α and IL-6 in contrast to OVA and Poly(I:C) administered in animals. A TLR3/dsRNA complex inhibitor decreased the fraction of oxidative stress markers (MDA, GSH, GPx, and CAT) in lung tissues while keeping the mice's body weight constant during the treatment period. By decreasing alveoli, bronchial narrowing, smooth muscle hypertrophy, and granulocyte levels, the TLR3/dsRNA complex blocker significantly reduced the histopathological damage caused by OVA and Poly(I:C) compounds. In an animal model utilizing ovalbumin, TLR3/dsRNA complex inhibitors similarly reduced the bronchial damage produced by Poly(I:C). A novel TLR3/dsRNA complex inhibitor is expected to be employed in clinical studies since it suppresses airway inflammation without inducing antiviral approach resistance.