A novel dicyanoisophorone-based fluorescent probe for rapid detection of acetylcholinesterase in biological systems.

Acetylcholinesterase (AChE) plays a vital role in various neurological diseases including brain disorders, neurotransmission alterations, and cancer. Developing effective methods to image AChE in biological samples is essential for understanding its mechanisms in biosystems. Here, we introduce a novel fluorescent probe CNA, that enables detection of AChE at 520 nm with rapid response time of 60 s and a detection limit of 0.

A xanthene-based fluorescent probe capable of selectively detecting phosgene in living mouse model.

In this study, we introduced a novel fluorescent probe RNP, which demonstrated outstanding sensitivity and specificity for phosgene detection. Upon phosgene exposure, the probe exhibited rapid fluorescence turn-on within a short re-sponse time (6 s). RNP was also effective in both cellular and murine experiments, where fluorescence enhancement was observed in the respiratory tract of mice.

A Novel Near-Infrared Fluorescent Probe for the Detection of Endogenous Peroxynitrite (ONOO) in Living Cells.

In this study, we present a novel near-infrared (NIR) fluorescent probe Nile-ONO designed for the selective and sensitive detection of ONOO. The probe Nile-ONO employed Nile red as the fluorophore, with diphenylphosphinate serving as the reaction site. In the presence of ONOO, the probe Nile-ONO exhibits remarkable fluorescence enhancement at 659 nm, with a response time of less than 20 min and a low detection limit of 0.

A novel lysosome-targeted fluorescent probe for precise formaldehyde detection in water samples, living cells and breast cancer tumors.

This study investigated the potential ability of the fluorescent probe Ly-CHO to detect formaldehyde (FA) in living cells and tumor-bearing mice. Ly-CHO exhibited great selectivity, excellent sensitivity, and rapid response to FA, making it a valuable tool for tracking FA concentration changes. The probe was also found to target lysosomes specifically.

Development of a fluorescence-based sensor based on 1,8-naphthalimide for highly sensitive detection of phosgene.

Developing advanced sensing technologies for phosgene is critical for public safety and national security. Here, we report a novel fluorescent probe NP (abbreviation for naphthalimide-based probe) for the selective detection of phosgene. The sensor was synthesized through a substitution reaction between 1,8-naphthalimide with 1,4,7-triazacyclononane.

Peroxynitrite scavenger FeTPPS effectively inhibits hIAPP aggregation and protects against amyloid induced cytotoxicity.

Type 2 diabetes (T2D) is associated with pancreatic β-cell dysfunction, which can be induced by oxidative stress or/and the aggregation of human islet amyloid polypeptide (hIAPP). Therefore, ONOO and hIAPP become the crucial targets of T2D treatment. Previously, we found heme could be an effective inhibitor of hIAPP aggregation.

Dual Anti-/Prooxidant Behaviors of Flavonoids Pertaining to Cu(II)-Catalyzed Tyrosine Nitration of the Insulin Receptor Kinase Domain in an Antidiabetic Study.

Flavonoid, as a potent antioxidant, exerts many beneficial effects in type 2 diabetes, whereas the prooxidative property may be also important in vivo if copper is involved. Here, we chose an insulin receptor kinase domain fragment (KK-1, residues 1126-1165), containing the A-loop of the receptor as well as three key autophosphorylation sites (Tyr, Tyr, and Tyr) associated with receptor signal transduction to investigate the roles and the structure-activity relationship of three antidiabetic flavonoids (kaempferol, luteolin, and apigenin) and two others with a similar structure (diosmetin and genistein), on modulation of Cu(II)-mediated tyrosine nitration and the corresponding effect on its functional phosphorylation in the Cu/HO/NO system. We found that both properties of flavonoid played roles on inhibition of Cu(II)-mediated protein nitration in the HO/NO system: (1) on the one hand, flavonoid scavenged free radicals as antioxidants, inhibited tyrosine nitration, and thus inhibited the reduction of tyrosine phosphorylation caused by tyrosine nitration; and (2) on the other hand, flavonoid promoted OH production as a prooxidant, which increased 3,3'-dityrosine formation.

Electrochemiluminescence Biosensor for Nucleolin Imaging in a Single Tumor Cell Combined with Synergetic Therapy of Tumor.

Nucleolin, a nuclear biological multifunctional protein, plays significant roles in modulating the proliferation, survival, and apoptosis of tumor cells. Different from the traditional electrochemiluminescence (ECL) method, a new ECL biosensor was built to perform ECL imaging of nucleolin in a single HeLa cell with high sensitivity and throughput. Briefly, mesoporous silica nanoparticles (MSN) loaded with doxorubicin (DOX) and phorbol 12-myristate 13-acetate (PMA) were used as drug carriers and could be specifically opened by nucleolin in a HeLa cell.

Electrochemiluminescence-Microscopy for microRNA Imaging in Single Cancer Cell Combined with Chemotherapy-Photothermal Therapy.

In this work, a new technology using ECL as a microscopy to parallel image miRNA-21 in single cancer cell was built. Phorbol-12-myristate-13-acetate (PMA) loaded gold nanocages (Au NCs) was closed with DNA gate which could be recognized and opened by miRNA-21 in HeLa cell. PMA was then released and further induced HeLa cells to produce reactive oxygen species (ROS; including O, •OH and HO etc.

Nitration of amyloid-β peptide (1-42) as a protective mechanism for the amyloid-β peptide (1-42) against copper ion toxicity.

It is known that copper ion (Cu(II)) binds to amyloid-β peptide (Aβ), induces Aβ oligomer formation and ultimately exacerbates Aβ-aggregation neurotoxicity in Alzheimer's disease (AD). It becomes interesting to know that how this chemical modification of Aβ would affect interaction of Aβ and Cu(II) and their roles in the development of AD. In this work, we investigated the interaction of Aβ nitration with the toxic Cu(II).

Triosephosphate isomerase tyrosine nitration induced by heme-NaNO -H O or peroxynitrite: Effects of different natural phenolic compounds.

Peroxynitrite and heme peroxidases (or heme)-H O -NaNO system are the two common ways to cause protein tyrosine nitration in vitro, but the effects of antioxidants on reducing these two pathways-induced protein nitration and oxidation are controversial. Both nitrating systems can dose-dependently induce triosephosphate isomerase (TIM) nitration, however, heme-H O -NaNO was less destructive to protein secondary structures and led to more nitrated tyrosine residue than 3-morpholinosydnonimine hydrochloride (SIN-1, a peroxynitrite donor). Both of desferrioxamine and catechin could inhibit TIM nitration induced by heme-H O -NaNO and SIN-1 and protein oxidation induced by SIN-1, but promoted heme-H O -NaNO -induced protein oxidation.

Synergistic Interaction of Light Alcohol Administration in the Presence of Mild Iron Overload in a Mouse Model of Liver Injury: Involvement of Triosephosphate Isomerase Nitration and Inactivation.

It is well known that iron overload promotes alcoholic liver injury, but the doses of iron or alcohol used in studies are usually able to induce liver injury independently. Little attention has been paid to the coexistence of low alcohol consumption and mild iron overload when either of them is insufficient to cause obvious liver damage, although this situation is very common among some people. We studied the interactive effects and the underlining mechanism of mild doses of iron and alcohol on liver injury in a mouse model.

Iron increases diabetes-induced kidney injury and oxidative stress in rats.

Diabetic nephropathy is both a common and a severe complication of diabetes mellitus. Iron is an essential trace element. However, excess iron is toxic, playing a role in the pathogenesis of diabetic nephropathy.