Limits...
Analysis on the alterations of lens proteins by Vitex negundo in selenite cataract models.

Rooban BN, Sasikala V, Sahasranamam V, Abraham A - Mol. Vis. (2011)

Bottom Line: Our study indicated that chaperone property of α-crystallin and soluble protein levels were reduced in the selenite induced group.Damage of lenticular membrane and abnormal fiber structure were observed by electron microscopy.The results of this study suggest that FVN modulated selenite induced cataractogensis in rat pups by preventing loss of chaperone property, various changes in lens proteins, and lens structure, further strengthening its protective role.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry, University of Kerala, Kariavattom, Thiruvananthapuram, India.

ABSTRACT

Purpose: Cataract is the leading cause of blindness and is associated with oxidative damage and protein modification in the lens. In the present study, we have employed proteomic and microscopic approaches to investigate the attenuation of selenite cataract by the flavonoids from Vitex negundo (FVN).

Methods: To demonstrate this attenuation, Sprague-Dawley rat pups were divided into control (G I), selenite induced (G II), and selenite + FVN treated (G III). Cataract was induced by single subcutaneous injection of sodium selenite (4 mg/Kg bodyweight) on the 10th day and FVN (1 mg/Kg bodyweight) administered intraperitoneally from the 8th to the 15th day.

Results: Our study indicated that chaperone property of α-crystallin and soluble protein levels were reduced in the selenite induced group. Post translational modifications identified by two dimensional-polyacrylamide gel electrophoresis (2D-PAGE) and immunoblot analysis revealed the loss of cytoskeletal proteins in selenite induced group. Damage of lenticular membrane and abnormal fiber structure were observed by electron microscopy.

Conclusions: The results of this study suggest that FVN modulated selenite induced cataractogensis in rat pups by preventing loss of chaperone property, various changes in lens proteins, and lens structure, further strengthening its protective role.

Show MeSH

Related in: MedlinePlus

Chaperone activity of α-crystallin. A: DTT induced aggregation of insulin - Light scattering of insulin in the absence of α-crystallin (curve 1), α-crystallin from selenite induced (curve 2), α-crystallin from control rats (curve 4), standard α-crystallin (curve 5), α-crystallin from FVN treated group (curve 3). Data are representative of three such independent assays for three separate lens extracts. B: Heat induced aggregation of βL-crystallin - absence of α-crystallin (curve 1), α-crystallin from selenite induced group (curve 2), α-crystallin from control (curve 4), standard α-crystallin (curve 5), α-crystallin from FVN treated group (curve 3). Data are representative of three such independent assays for three separate lens extracts.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3102022&req=5

f3: Chaperone activity of α-crystallin. A: DTT induced aggregation of insulin - Light scattering of insulin in the absence of α-crystallin (curve 1), α-crystallin from selenite induced (curve 2), α-crystallin from control rats (curve 4), standard α-crystallin (curve 5), α-crystallin from FVN treated group (curve 3). Data are representative of three such independent assays for three separate lens extracts. B: Heat induced aggregation of βL-crystallin - absence of α-crystallin (curve 1), α-crystallin from selenite induced group (curve 2), α-crystallin from control (curve 4), standard α-crystallin (curve 5), α-crystallin from FVN treated group (curve 3). Data are representative of three such independent assays for three separate lens extracts.

Mentions: This was performed with α-crystallin isolated from control, selenite induced, and V. negundo treated rats by two methods. In DTT induced aggregation of insulin assay, reduction of disulfide bonds connecting insulin A- and B-chains leads to the unfolding and aggregation of the B-chain. This aggregation is suppressed by α-crystallin, which binds to a non-native conformer of the B-chain. Data are representative of three such independent assays for three separate lens extracts. Figure 3A shows the relative chaperone activity of α-crystallin isolated from the three groups. Light scattering of insulin was increased in the absence of α crystallin (Figure 3A, curve 1). Chaperone activity of α-crystallin isolated from selenite induced group was diminished (Figure 3A, curve 2), but this aggregation was completely suppressed by α crystallin isolated from control rats (Figure 3A, curve 4) compared with standard α crystallin (Figure 3A, curve 5). However, protection from aggregation increased markedly using α-crystallin from FVN treated group (Figure 3A, curve 3) compared with control. In heat induced aggregation of βL-crystallin assay, as shown in Figure 3B aggregation of βL-crystallin was increased at 60 °C in the absence of α crystallin (Figure 3B, curve 1). The chaperone activity of α-crystallin isolated from selenite induced group showed a marginally decreased activity (Figure 3B, curve 2) compared with control (Figure 3B, curve 4). However, improved chaperone function of α-crystallin was found in FVN treated group (Figure 3B, curve 3).


Analysis on the alterations of lens proteins by Vitex negundo in selenite cataract models.

Rooban BN, Sasikala V, Sahasranamam V, Abraham A - Mol. Vis. (2011)

Chaperone activity of α-crystallin. A: DTT induced aggregation of insulin - Light scattering of insulin in the absence of α-crystallin (curve 1), α-crystallin from selenite induced (curve 2), α-crystallin from control rats (curve 4), standard α-crystallin (curve 5), α-crystallin from FVN treated group (curve 3). Data are representative of three such independent assays for three separate lens extracts. B: Heat induced aggregation of βL-crystallin - absence of α-crystallin (curve 1), α-crystallin from selenite induced group (curve 2), α-crystallin from control (curve 4), standard α-crystallin (curve 5), α-crystallin from FVN treated group (curve 3). Data are representative of three such independent assays for three separate lens extracts.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3102022&req=5

f3: Chaperone activity of α-crystallin. A: DTT induced aggregation of insulin - Light scattering of insulin in the absence of α-crystallin (curve 1), α-crystallin from selenite induced (curve 2), α-crystallin from control rats (curve 4), standard α-crystallin (curve 5), α-crystallin from FVN treated group (curve 3). Data are representative of three such independent assays for three separate lens extracts. B: Heat induced aggregation of βL-crystallin - absence of α-crystallin (curve 1), α-crystallin from selenite induced group (curve 2), α-crystallin from control (curve 4), standard α-crystallin (curve 5), α-crystallin from FVN treated group (curve 3). Data are representative of three such independent assays for three separate lens extracts.
Mentions: This was performed with α-crystallin isolated from control, selenite induced, and V. negundo treated rats by two methods. In DTT induced aggregation of insulin assay, reduction of disulfide bonds connecting insulin A- and B-chains leads to the unfolding and aggregation of the B-chain. This aggregation is suppressed by α-crystallin, which binds to a non-native conformer of the B-chain. Data are representative of three such independent assays for three separate lens extracts. Figure 3A shows the relative chaperone activity of α-crystallin isolated from the three groups. Light scattering of insulin was increased in the absence of α crystallin (Figure 3A, curve 1). Chaperone activity of α-crystallin isolated from selenite induced group was diminished (Figure 3A, curve 2), but this aggregation was completely suppressed by α crystallin isolated from control rats (Figure 3A, curve 4) compared with standard α crystallin (Figure 3A, curve 5). However, protection from aggregation increased markedly using α-crystallin from FVN treated group (Figure 3A, curve 3) compared with control. In heat induced aggregation of βL-crystallin assay, as shown in Figure 3B aggregation of βL-crystallin was increased at 60 °C in the absence of α crystallin (Figure 3B, curve 1). The chaperone activity of α-crystallin isolated from selenite induced group showed a marginally decreased activity (Figure 3B, curve 2) compared with control (Figure 3B, curve 4). However, improved chaperone function of α-crystallin was found in FVN treated group (Figure 3B, curve 3).

Bottom Line: Our study indicated that chaperone property of α-crystallin and soluble protein levels were reduced in the selenite induced group.Damage of lenticular membrane and abnormal fiber structure were observed by electron microscopy.The results of this study suggest that FVN modulated selenite induced cataractogensis in rat pups by preventing loss of chaperone property, various changes in lens proteins, and lens structure, further strengthening its protective role.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry, University of Kerala, Kariavattom, Thiruvananthapuram, India.

ABSTRACT

Purpose: Cataract is the leading cause of blindness and is associated with oxidative damage and protein modification in the lens. In the present study, we have employed proteomic and microscopic approaches to investigate the attenuation of selenite cataract by the flavonoids from Vitex negundo (FVN).

Methods: To demonstrate this attenuation, Sprague-Dawley rat pups were divided into control (G I), selenite induced (G II), and selenite + FVN treated (G III). Cataract was induced by single subcutaneous injection of sodium selenite (4 mg/Kg bodyweight) on the 10th day and FVN (1 mg/Kg bodyweight) administered intraperitoneally from the 8th to the 15th day.

Results: Our study indicated that chaperone property of α-crystallin and soluble protein levels were reduced in the selenite induced group. Post translational modifications identified by two dimensional-polyacrylamide gel electrophoresis (2D-PAGE) and immunoblot analysis revealed the loss of cytoskeletal proteins in selenite induced group. Damage of lenticular membrane and abnormal fiber structure were observed by electron microscopy.

Conclusions: The results of this study suggest that FVN modulated selenite induced cataractogensis in rat pups by preventing loss of chaperone property, various changes in lens proteins, and lens structure, further strengthening its protective role.

Show MeSH
Related in: MedlinePlus