Dataset Information

Aggrelyte-2 Promotes Protein Solubility and Decreases Stiffness in Lenses through Lysine Acetylation and Disulfide Reduction

ABSTRACT: Aging proteins in the lens become increasingly aggregated and insoluble, contributing to presbyopia. In this study, we investigated the ability of aggrelyte-2 (N,S-Diacetyl-L-cysteine methyl ester) to reverse the water insolubility of aged human lens proteins and to decrease stiffness in cultured human and rodent lenses. Aggrelyte-2 was incubated (500 µM) with water-insoluble proteins of aged human lenses (65-75 years) for 24 or 48 h. A control compound that lacked an S-acetyl group (aggrelyte-2C) was also tested. We observed 19-30% solubility of WI upon the treatment with aggrelyte-2. Aggrelyte-2C also increased protein solubility, but its effect was approximately 1.4-fold lower than that of aggrelyte-2. The protein thiol contents were 1.9 to 4.9-fold higher in the aggrelyte-treated samples than in the untreated samples. The LC-MS/MS results showed N-acetyllysine (AcK) levels of 1.5 to 2.1 nmoles/mg protein and 0.6 to 0.9 nmoles/mg protein in the aggrelyte-2- and aggrelyte-2C-treated samples, respectively. Mouse (C57BL/6J) lenses (incubated for 24 h) and human lenses (incubated for 72 h) with 1.0 mM aggrelyte-2 showed significant decreases in stiffness with simultaneous increases in soluble proteins (human lenses) and protein-AcK levels and such changes were not observed in aggrelyte-2C treated lenses. Mass spectrometry of the solubilized protein revealed AcK in all crystallins but more in α-crystallins. These results suggest that aggrelyte-2 increases protein solubility and decreases lens stiffness through acetylation and disulfide reduction. Aggrelyte-2 might be useful in treating presbyopia in humans.

INSTRUMENT(S): 6520A Quadrupole Time-of-Flight LC/MS

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Eye

SUBMITTER: Cole Michel

LAB HEAD: Cole Michel

PROVIDER: PXD035049 | Pride | 2023-05-10

REPOSITORIES: Pride

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Aggrelyte-2 promotes protein solubility and decreases lens stiffness through lysine acetylation and disulfide reduction: Implications for treating presbyopia.

Panja Sudipta S Nahomi Rooban B RB Rankenberg Johanna J Michel Cole R CR Gaikwad Hanmant H Nam Mi-Hyun MH Nagaraj Ram H RH

Aging cell 20230223 4

Aging proteins in the lens become increasingly aggregated and insoluble, contributing to presbyopia. In this study, we investigated the ability of aggrelyte-2 (N,S-diacetyl-L-cysteine methyl ester) to reverse the water insolubility of aged human lens proteins and to decrease stiffness in cultured human and mouse lenses. Water-insoluble proteins (WI) of aged human lenses (65-75 years) were incubated with aggrelyte-2 (500 μM) for 24 or 48 h. A control compound that lacked the S-acetyl group (aggre ...[more]

PMID: 36823285

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			Action	DRS
	Ram_ACIL2_5uL.d.zip	Other
	Ram_ACIL2_5uL.mzxml	Mzxml
	Ram_Control_5uL.d.zip	Other
	Ram_Control_5uL.mzxml	Mzxml
	peptide.csv	Csv