Potential effect of amniotic fluid-derived stem cells on hyperoxia-induced pulmonary alveolar injury

Brain-targeted Tet-1 peptide-PLGA nanoparticles for berberine delivery against STZ-induced Alzheimer's disease in a rat model: Alleviation of hippocampal synaptic dysfunction, Tau pathology, and amyloidogenesis

Alzheimer's disease (AD) is an age-related neurodegenerative disorder that causes severe dementia and memory loss. Surface functionalized poly(lactic-co-glycolic acid) nanoparticles have been reported for better transport through the blood-brain barrier for AD therapy. This study investigated the improved therapeutic potential of berberine-loaded poly(lactic-co-glycolic acid)/Tet-1 peptide nanoparticles (BBR/PLGA-Tet NPs) in a rat model of sporadic AD. BBR was loaded into the PLGA-Tet conjugate. BBR/PLGA-Tet NPs were physicochemically and morphologically characterized. AD was achieved by bilateral intracerebroventricular (ICV) injection of streptozotocin (STZ). Cognitively impaired rats were divided into STZ, STZ + BBR, STZ + BBR/PLGA-Tet NPs, and STZ + PLGA-Tet NPs groups. Cognitive improvement was assessed using the Morris Water Maze. Brain acetylcholinesterase and monoamine oxidase activities, amyloid β42 (Aβ42), and brain glycemic markers were estimated. Further, hippocampal neuroplasticity (BDNF, pCREB, and pERK/ERK), Tau pathogenesis (pGSK3β/GSK3β, Cdk5, and pTau), inflammatory, and apoptotic markers were evaluated. Finally, histopathological changes were monitored. ICV-STZ injection produces AD-like pathologies evidenced by Aβ42 deposition, Tau hyperphosphorylation, impaired insulin signaling and neuroplasticity, and neuroinflammation. BBR and BBR/PLGA-Tet NPs attenuated STZ-induced hippocampal damage, enhanced cognitive performance, and reduced Aβ42, Tau phosphorylation, and proinflammatory responses. BBR/PLGA-Tet NPs restored neuroplasticity, cholinergic, and monoaminergic function, which are critical for cognition and brain function. BBR/PLGA-Tet NPs may have superior therapeutic potential in alleviating sporadic AD than free BBR due to their bioavailability, absorption, and brain uptake.

An endogenous amniotic fluid-derived 10-amino acid peptide improves lung development and hyperoxia injury

BACKGROUND

Bronchopulmonary dysplasia (BPD) is a chronic lung disease that occurs in preterm infants and lacks effective treatment. We aim to reveal the relationship between amniotic fluid (AF) peptides and lung development by analyzing the differences in the composition of AF peptides at different gestational periods, thus providing a new means of prevention and treatment for BPD.

METHODS

Based on the stages of lung development, we collected AF by amniocentesis in two different gestational periods, using the 25th week of pregnancy as the cut-off. We conducted a peptide omics analysis of these AF samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Additionally, we verified the regulatory effects of hyperoxia and the peptide COL5A2 on BPD-related cells [(mouse lung epithelial (MLE-12) cells] by 5-Ethynyl-2'-deoxyuridine (EdU) staining, JC-1 staining, flow cytometry, and reactive oxygen species (ROS) assay.

RESULTS

There were 131 differentially expressed peptides, including 85 up-regulated and 46 down-regulated [fold change (FC) ≥1.2 or ≤1/1.2, P<0.05], in the ≥25 weeks' gestation group compared to the <25 weeks' gestation group. Further bioinformatics analysis revealed that the precursor proteins of the differentially expressed peptides between these two groups were involved in the regulation of the developmental process, anatomical structure development, and other biological processes, suggesting that these differential peptides may play a key role in lung development. We found peptide COL5A2 with the sequence GPPGEPGPPG and verified the regulatory effects of COL5A2 on the proliferation, apoptosis, cell viability, and ROS levels of MLE-12 cells by cell assays.

CONCLUSIONS

In this study, peptidomic studies using AF from different gestational periods revealed that peptides in AF may be involved in lung development. They could be used in the future to assist in the postnatal development of preterm infants and provide new therapeutic prospects for BPD.