Inhibition of Prolyl Oligopeptidase Prevents Consequences of Reperfusion following Intestinal Ischemia

bFGF-like Activity Supported Tissue Regeneration, Modulated Neuroinflammation, and Rebalanced Ca2+ Homeostasis following Spinal Cord Injury

A spinal cord injury (SCI) is a well-defined debilitating traumatic event to the spinal cord that usually triggers permanent changes in motor, sensory, and autonomic functions. Injured tissue becomes susceptible to secondary mechanisms caused by SCIs, which include pro-inflammatory cytokine release, the activation of astrocytes and microglia, and increased neuronal sensibility. As a consequence, the production of factors such as GFAP, IBA-1, TNF-α, IL-1β, IFN-γ, and S100-β slow down or inhibit central nervous system (CNS) regeneration. In this regard, a thorough understanding of the mechanisms regulating the CNS, and specifically SCI, is essential for the development of new therapeutic strategies. It has been demonstrated that basic fibroblast growth factor (bFGF) was successful in the modulation of neurotrophic activity, also promoting neurite survival and tissue repair, thus resulting in the valuable care of CNS disorders. However, bFGF therapeutic use is limited due to the undesirable effects developed following its administration. Therefore, the synthetic compound mimetic of bFGF, SUN11602 (with chemical name 4-[[4-[[2-[(4-Amino-2,3,5,6-tetramethylphenyl)amino]acetyl]methylamino]-1-piperidinyl]methyl]benzamide), has been reported to show neuroprotective activities similar to those of bFGF, also demonstrating a good pharmacokinetic profile. Here, we aimed to investigate the neuroprotective activity of this bFGF-like compound in modulating tissue regeneration, neuroinflammation, and Ca2+ overload by using a subacute mouse model of SCI. SUN11602 (1, 2.5, and 5 mg/kg) was administered orally to mice for 72 h daily following the in vivo model of SCI, which was generated by the extradural compression of the spinal cord. The data obtained demonstrated that SUN11602 treatment considerably decreased motor alteration and diminished the neuroinflammatory state through the regulation of glial activation, the NF-κB pathway, and kinases. Additionally, by controlling Ca2+-binding proteins and restoring neurotrophin expression, we showed that SUN11602 therapy restored the equilibrium of the neuronal circuit. Because of these findings, bFGF-like compounds may be an effective tool for reducing inflammation in SCI patients while enhancing their quality of life.

Prolyl oligopeptidase inhibition ameliorates experimental pulmonary fibrosis both in vivo and in vitro

BACKGROUND

Pulmonary fibrosis is a progressive disease characterized by lung remodeling due to excessive deposition of extracellular matrix. Although the etiology remains unknown, aberrant angiogenesis and inflammation play an important role in the development of this pathology. In this context, recent scientific research has identified new molecules involved in angiogenesis and inflammation, such as the prolyl oligopeptidase (PREP), a proteolytic enzyme belonging to the serine protease family, linked to the pathology of many lung diseases such as pulmonary fibrosis. Therefore, the aim of this study was to investigate the effect of a selective inhibitor of PREP, known as KYP-2047, in an in vitro and in an in vivo model of pulmonary fibrosis.

METHODS

The in vitro model was performed using human alveolar A549 cells. Cells were exposed to lipopolysaccharide (LPS) 10 μg/ml and then, cells were treated with KYP-2047 at the concentrations of 1 μM, 10 μM and 50 μM. Cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) bromide colorimetric assay, while inflammatory protein expression was assessed by western blots analysis. The in vivo model was induced in mice by intra-tracheal administration of bleomycin (1 mg/kg) and then treated intraperitoneally with KYP-2047 at doses of 1, 2.5 and 5 mg/kg once daily for 12 days and then mice were sacrificed, and lung tissues were collected for analyses.

RESULTS

The in vitro results demonstrated that KYP-2047 preserved cell viability, reduced inflammatory process by decreasing IL-18 and TNF-α, and modulated lipid peroxidation as well as nitrosative stress. The in vivo pulmonary fibrosis has demonstrated that KYP-2047 was able to restore histological alterations reducing lung injury. Our data demonstrated that KYP-2047 significantly reduced angiogenesis process and the fibrotic damage modulating the expression of fibrotic markers. Furthermore, KYP-2047 treatment modulated the IκBα/NF-κB pathway and reduced the expression of related pro-inflammatory enzymes and cytokines. Moreover, KYP-2047 was able to modulate the JAK2/STAT3 pathway, highly involved in pulmonary fibrosis.

CONCLUSION

In conclusion, this study demonstrated the involvement of PREP in the pathogenesis of pulmonary fibrosis and that its inhibition by KYP-2047 has a protective role in lung injury induced by BLM, suggesting PREP as a potential target therapy for pulmonary fibrosis. These results speculate the potential protective mechanism of KYP-2047 through the modulation of JAK2/STAT3 and NF-κB pathways.

Sodium Propionate Contributes to Tumor Cell Growth Inhibition through PPAR-γ Signaling

New therapeutic approaches are needed to improve the outcome of patients with glioblastoma (GBM). Propionate, a short-chain fatty acid (SCFA), has a potent antiproliferative effect on various tumor cell types. Peroxisome proliferator-activated receptor (PPAR) ligands possess anticancer properties. We aimed to investigate the PPAR-γ/SCFAs interaction in in vitro and in vivo models of GBM. The U87 cell line was used in the in vitro study and was treated with sodium propionate (SP). U87 cells were silenced by using PPAR-γ siRNA or Ctr siRNA. In the in vivo study, BALB/c nude mice were inoculated in the right flank with 3 × 10⁶ U-87 cells. SP (doses of 30 and 100 mg/kg) and GW9662 (1 mg/kg) were administered. In vitro exposure of GBM to SP resulted in prominent apoptosis activation while the autophagy pathway was promoted by SP treatments by influencing autophagy-related proteins. Knockdown of PPAR-γ sensitized GBM cells and blocked the SP effect. In vivo, SP was able to decrease tumor growth and to resolve GBM tissue features. SP promoted apoptosis and autophagy pathways and tumor cell proliferation leading to cell cycle arrest through a PPAR-γ-dependent mechanism suggesting that the PPAR-γ/SCFAs axis could be targeted for the management of GBM.

A Combination of Xyloglucan, Pea Protein and Chia Seed Ameliorates Intestinal Barrier Integrity and Mucosa Functionality in a Rat Model of Constipation-Predominant Irritable Bowel Syndrome

Irritable Bowel Syndrome is a gastrointestinal disorder that affects the large intestine, which encompasses several symptoms including, but not limited to, abdominal pain, bloating and dysmotility. In particular, IBS associated with constipation (IBS-C) is characterized by hard and dry stools and inadequate evacuation and difficulty in defecation. Although several drugs ameliorate intestinal modifications and constipation-associated features, management of IBS is still a challenge. Natural compounds including Xyloglucan and pea protein (XP) and Chia seed powder (CS) are widely known to possess beneficial effects in counteracting several gastrointestinal disorders. Here, we aimed to assess the combined effects of XP and CS to treat constipation-related alterations in an IBS-C rat model. IBS-C was induced by gastric instillation of 2 mL of cold water (0-4 °C) for 14 days and Xiloglucan, Pea protein and Chia seeds (XP + CS) treatment was orally administered for 7 days. On day 22, colon tissues were collected for histological analysis. Our results showed that XP + CS administration attenuated constipation-related parameters by increasing body weight and food and water intake. Upon XP + CS treatment, from day 14 to 22, stool moisture content was restored to physiological level. Colonic tissues from IBS-C rats depicted a disruption of the organ architecture accompanied by edema. Loss of colonic structure was reflected by the marked reduction of tight junction protein expression, Occludin and zona occludens-1 (ZO-1). Administration of XP + CS treatment in IBS-C rats significantly ameliorated the colonic histological parameters and exerted a positive effect on barrier integrity by restoring the expression of Occludin and zona occludens-1 (ZO-1). Our findings demonstrated that the efficacy of XP and CS in managing constipation in rats is due to the ability of these compounds to form a protective barrier fortifying intestinal integrity and gut functionality.

LRRK2 Inhibition by PF06447475 Antagonist Modulates Early Neuronal Damage after Spinal Cord Trauma

Spinal cord injury (SCI) is a devastating event followed by neurodegeneration, activation of the inflammatory cascade, and immune system. The leucine-rich-repeat kinase 2 (LRRK2) is a gene associated with Parkinson’s disease (PD), moreover, its kinase activity was found to be upregulated after instigated inflammation of the central nervous system (CNS). Here, we aimed to investigate the PF06447475 (abbreviated as PF-475) role as a pharmacological LRRK2 antagonist by counteracting pathological consequences of spinal cord trauma. The in vivo model of SCI was induced by extradural compression of the spinal cord, then mice were treated with PF0-475 (2.5–5 and 10 mg/kg i.p) 1 and 6 h after SCI. We found that PF-475 treatments at the higher doses (5 and 10 mg/kg) showed a great ability to significantly reduce the degree of spinal cord tissue injury, glycogen accumulation, and demyelination of neurons associated with trauma. Furthermore, oxidative stress and cytokines expression levels, including interleukins (IL-1, IL-6, IL-10, and 12), interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α), secreted and released after trauma were decreased by LRRK2 antagonist treatments. Our results suggest that the correlations between LRRK2 and inflammation of the CNS exist and that LRRK2 activity targeting could have direct effects on the intervention of neuroinflammatory disorders.

Ulva pertusa, a Marine Green Alga, Attenuates DNBS-Induced Colitis Damage via NF-κB/Nrf2/SIRT1 Signaling Pathways

Inflammatory bowel diseases (IBD) including Crohn's disease (CD) and ulcerative colitis (UC) represent gastrointestinal (GI) disorders associated with varied responses to microbial and environmental agents. Natural compounds have been suggested as a valid approach to the management of various GI diseases, particularly the green alga Ulva pertusa, belonging to the Ulvaceae family, which showed powerful biological properties. Here, we aimed to evaluate the effect and the mechanism of Ulva pertusa treatments in a murine model of DNBS-induced colitis. Colitis was induced by DNBS intrarectal installation (4 mg in 100 μL of 50% ethanol), while Ulva pertusa treatments (doses of 10, 50 and 100 mg/kg) were administered orally daily. Ulva pertusa, at the higher doses of 50 and 100 mg/kg, significantly reduced tissue damage DNBS-induced and the consequent inflammatory cascade via NF-κB inhibition. Furthermore, we demonstrated, for the first time, Ulva pertusa action on the SIRT1/Nrf2 axis, enhancing antioxidant response and the modulation of the apoptosis pathway colitis-induced, regulating the expression of p53, Bax, Bcl-2, and Caspases. Taken together, Ulva pertusa could be considered a valid approach for counteracting and blocking the progression of IBDs through modulation of the NF-κB/SIRT1/Nrf2 axis.