Alteration in memory cognition due to activation of caveolin-1 and oxidative damage in a model of dementia of Alzheimer's type

Caveolin-1 is essential for the increased release of glutamate in the anterior cingulate cortex in neuropathic pain mice

Neuropathic pain has a complex pathogenesis. Here, we examined the role of caveolin-1 (Cav-1) in the anterior cingulate cortex (ACC) in a chronic constriction injury (CCI) mouse model for the enhancement of presynaptic glutamate release in chronic neuropathic pain. Cav-1 was localized in glutamatergic neurons and showed higher expression in the ACC of CCI versus sham mice. Moreover, the release of glutamate from the ACC of the CCI mice was greater than that of the sham mice. Inhibition of Cav-1 by siRNAs greatly reduced the release of glutamate of ACC, while its overexpression (induced by injecting Lenti-Cav-1) reversed this process. The chemogenetics method was then used to activate or inhibit glutamatergic neurons in the ACC area. After 21 days of injection of AAV-hM3Dq in the sham mice, the release of glutamate was increased, the paw withdrawal latency was shortened, and expression of Cav-1 in the ACC was upregulated after intraperitoneal injection of 2 mg/kg clozapine N-oxide. Injection of AAV-hM4Di in the ACC of CCI mice led to the opposite effects. Furthermore, decreasing Cav-1 in the ACC in sham mice injected with rAAV-hM3DGq did not increase glutamate release. These findings suggest that Cav-1 in the ACC is essential for enhancing glutamate release in neuropathic pain.

Suspension TRAPping Filter (sTRAP) Sample Preparation for Quantitative Proteomics in the Low µg Input Range Using a Plasmid DNA Micro-Spin Column: Analysis of the Hippocampus from the 5xFAD Alzheimer's Disease Mouse Model

Suspension TRAPping filter (sTRAP) is an attractive sample preparation method for proteomics studies. The sTRAP protocol uses 5% SDS that maximizes protein solubilization. Proteins are trapped on a borosilicate glass membrane filter, where SDS is subsequently removed from the filter. After trypsin digestion, peptides are analyzed directly by LC-MS. Here, we demonstrated the use of a low-cost plasmid DNA micro-spin column for the sTRAP sample preparation of a dilution series of a synapse-enriched sample with a range of 10-0.3 µg. With 120 ng tryptic peptides loaded onto the Evosep LC system coupled to timsTOF Pro 2 mass spectrometer, we identified 5700 protein groups with 4% coefficient of variation (CoV). Comparing other sample preparation protocols, such as the in-gel digestion and the commercial Protifi S-TRAP with the plasmid DNA micro-spin column, the last is superior in both protein and peptide identification numbers and CoV. We applied sTRAP for the analysis of the hippocampal proteome from the 5xFAD mouse model of Alzheimer's disease and their wildtype littermates, and revealed 121 up- and 54 down-regulated proteins. Protein changes in the mutant mice point to the alteration of processes related to the immune system and Amyloid aggregation, which correlates well with the known major Alzheimer's-disease-related pathology. Data are available via ProteomeXchange with the identifier PXD041045.

A DNase-mimetic artificial enzyme for the eradication of drug-resistant bacterial biofilm infections

The construction of multifunctional nano-enzymes is a feasible strategy for fighting multi-drug resistant (MDR) bacterial biofilm-associated infections. Extracellular DNA (eDNA) is an important functional part of biofilm formation, including the initial adherence of bacteria to subsequent development and eventual maturation. A nano-enzyme platform of graphene oxide-based nitrilotriacetic acid-cerium(IV) composite (GO-NTA-Ce) against bacterial biofilm infection has been developed. When located at the site of bacteria-associated infection, GO-NTA-Ce could inhibit the biofilm formation and effectively disperse the formed biofilm by degrading the eDNA. In addition to Ce-mediated deoxyribonuclease (DNase)-like activity, near-infrared laser irradiation of GO-NTA-Ce could produce local hyperthermia to kill the bacteria that lost the protection by the biofilm matrix. In addition, graphene is also a new green broad-spectrum antimicrobial material that can exert its antimicrobial effects through physical damage and chemical damage. In short, our GO-NTA-Ce nano-enzyme platform is capable of effectively eradicating drug-resistant bacterial biofilm infections through the triple action of DNase-like enzyme properties, photothermal therapy, and graphene-based antimicrobial activity, and the nano-composite has excellent potential for the treatment of MDR bacterial biofilm infections.

Role of caveolin-1 in human organ function and disease: friend or foe?

Caveolin-1 (Cav-1) is a structural protein component of caveolae, which are invaginations of the plasma membrane involved in various cellular processes, including endocytosis, extracellular matrix organization, cholesterol distribution, cell migration, and signaling. Mounting evidence over the last 10-15 years has demonstrated a central role of Cav-1 in many diseases, such as cancer, diabetes, and fibrosis. Cav-1 plays positive and negative roles in various diseases through its different regulation pathways. Here, we review the current knowledge on Cav-1 in different diseases and discuss the role of this protein in human organs and diseases.

Age-related increase in caveolin-1 expression facilitates cell-to-cell transmission of α-synuclein in neurons

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease, with aging being considered the greatest risk factor for developing PD. Caveolin-1 (Cav-1) is known to participate in the aging process. Recent evidence indicates that prion-like propagation of misfolded α-synuclein (α-syn) released from neurons to neighboring neurons plays an important role in PD progression. In the present study, we demonstrated that cav-1 expression in the brain increased with age, and considerably increased in the brain of A53T α-syn transgenic mice. Cav-1 overexpression facilitated the uptake of α-syn into neurons and formation of additional Lewy body-like inclusion bodies, phosphorylation of cav-1 at tyrosine 14 was found to be crucial for this process. This study demonstrates the relationship between age and α-syn spread and will facilitate our understanding of the molecular mechanism of the cell-to-cell transmission of α-syn.

Caveolin-1, a novel player in cognitive decline

Cognitive decline (CD), which related to vascular dementia, Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis and diabetes mellitus, is a growing health concern that has a great impact on the patients' quality of life. Although extensive efforts, the mechanisms of CD are still far from being clarified, not to mention the effective treatment and prevention strategies. Caveolin-1 (Cav-1), a trans-membrane protein, is a major component of the caveolae structure and scaffolding proteins. Recently, ample evidence depicts a strong correlation between Cav-1 and CD, however, the specific role of Cav-1 in CD has not been clearly examined and how they might be connected have yet to be identified. This review seeks to provide a comprehensive overview about how Cav-1 modulates pathogeneses of CD-associated diseases. In summary, Cav-1 can promote structural and functional plasticity of neurons, improve neurogenesis, relieve mitochondrial dysfunction, inhibit inflammation and suppress oxidative stress, which have shed light on the idea that Cav-1 may be an efficacious therapeutic target to treat CD.

Phycocyanin alleviates ICV-STZ induced cognitive and molecular deficits via PI3-Kinase dependent pathway

In this study, the effect of Phycocyanin (Pc) to ameliorate the cognitive dysfunction in experimental model of Alzheimer's disease (AD) was evaluated. Intracerebroventricular (ICV) induction of Streptozotocin (STZ) (3 mg/kg) was done bilaterally twice in rats on alternative days. Rats were injected with Pc (50, 100 mg/kg; i. p.) for 28 days daily for behavioural and cholinergic activity assessment. As the effect was only significant at 100 mg/kg, later molecular experiments were performed using the same only. STZ induction led to increased activity of hippocampal cholinesterases and BAX and decreased activity of BCL-2 and ChAT. It enhanced TNF-α, and NF-κB in rat's brain and reduced BDNF and IGF-1 levels. Dysfunctional insulin signaling and decreased gene expressions of PI3-K, AKT was also observed. However, Pc treatment significantly prevented STZ-induced increased activity of hippocampal cholinesterases and BAX as well as increased the levels of BCL-2 and ChAT. Neuroinflammation was significantly attenuated and BDNF and IGF-1 levels were upregulated. Further, Pc also alleviated dysfunctional insulin signaling as evidenced by increased gene expression of IRS-1, PI3-K, AKT. In conclusion, our study demonstrated the immense potential of Pc in attenuating STZ-induced cognitive decline and it may be further explored as a therapeutic agent in managing AD.