Limits...
Epigallocatechin-3-gallate rapidly remodels PAP85-120, SEM1(45-107), and SEM2(49-107) seminal amyloid fibrils.

Castellano LM, Hammond RM, Holmes VM, Weissman D, Shorter J - Biol Open (2015)

Bottom Line: Here, we confirm that the green tea polyphenol, epigallocatechin-3-gallate (EGCG), slowly remodels fibrils formed by PAP248-286 termed SEVI (semen derived enhancer of viral infection) and also exerts a direct anti-viral effect.We elucidate for the first time that EGCG remodels PAP85-120, SEM1(45-107), and SEM2(49-107) fibrils more rapidly than SEVI fibrils.The combined anti-amyloid and anti-viral properties of EGCG could have utility in preventing HIV transmission.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA Pharmacology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.

No MeSH data available.


Related in: MedlinePlus

EGCG rapidly remodels SEM2(49-107) fibrils. (A) SEM2(49-107) fibrils (20 µM) were incubated with buffer or EGCG (200 µM) for 0–24 h. Fibril integrity was assessed by measuring: ThT fluorescence intensity (A), OC immunoreactivity (B), turbidity (C), or sedimentation analysis (D). Values represent means±s.e.m. (n=3). (E) Transmission electron micrographs of SEM2(49-107) fibrils incubated with buffer or EGCG for 2 h. Scale bar: 500 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4582112&req=5

BIO010215F4: EGCG rapidly remodels SEM2(49-107) fibrils. (A) SEM2(49-107) fibrils (20 µM) were incubated with buffer or EGCG (200 µM) for 0–24 h. Fibril integrity was assessed by measuring: ThT fluorescence intensity (A), OC immunoreactivity (B), turbidity (C), or sedimentation analysis (D). Values represent means±s.e.m. (n=3). (E) Transmission electron micrographs of SEM2(49-107) fibrils incubated with buffer or EGCG for 2 h. Scale bar: 500 nm.

Mentions: Next, we tested whether EGCG could also remodel SEM1(45-107) fibrils. The ThT fluorescence intensity decayed drastically to ∼25% of the initial value for SEM1(45-107) immediately following the addition of a ten-fold excess of EGCG (Fig. 3A). Only a minor additional decline in ThT intensity to ∼18% of the initial value was observed for SEM1(45-107) fibrils after 24 h of incubation with EGCG (Fig. 3A). OC immunoreactivity, turbidty, and sedimentation analysis also revealed that EGCG remodeled SEM1(45-107) fibrils, but as with PAP85-120 fibrils, remodeling assessed by these measures was only observed at 2 h or later (Fig. 3B-D). Examination by TEM revealed that EGCG-remodeled SEM1(45-107) products were very small oligomeric structures (Fig. 3E). Very similar observations were made with SEM2(49-107) fibrils, which were also rapidly remodeled by EGCG (Fig. 4A-E). These findings suggest that EGCG disrupts critical contacts that are required to maintain SEM1(45-107) and SEM2(49-107) fibrils.Fig. 3.


Epigallocatechin-3-gallate rapidly remodels PAP85-120, SEM1(45-107), and SEM2(49-107) seminal amyloid fibrils.

Castellano LM, Hammond RM, Holmes VM, Weissman D, Shorter J - Biol Open (2015)

EGCG rapidly remodels SEM2(49-107) fibrils. (A) SEM2(49-107) fibrils (20 µM) were incubated with buffer or EGCG (200 µM) for 0–24 h. Fibril integrity was assessed by measuring: ThT fluorescence intensity (A), OC immunoreactivity (B), turbidity (C), or sedimentation analysis (D). Values represent means±s.e.m. (n=3). (E) Transmission electron micrographs of SEM2(49-107) fibrils incubated with buffer or EGCG for 2 h. Scale bar: 500 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4582112&req=5

BIO010215F4: EGCG rapidly remodels SEM2(49-107) fibrils. (A) SEM2(49-107) fibrils (20 µM) were incubated with buffer or EGCG (200 µM) for 0–24 h. Fibril integrity was assessed by measuring: ThT fluorescence intensity (A), OC immunoreactivity (B), turbidity (C), or sedimentation analysis (D). Values represent means±s.e.m. (n=3). (E) Transmission electron micrographs of SEM2(49-107) fibrils incubated with buffer or EGCG for 2 h. Scale bar: 500 nm.
Mentions: Next, we tested whether EGCG could also remodel SEM1(45-107) fibrils. The ThT fluorescence intensity decayed drastically to ∼25% of the initial value for SEM1(45-107) immediately following the addition of a ten-fold excess of EGCG (Fig. 3A). Only a minor additional decline in ThT intensity to ∼18% of the initial value was observed for SEM1(45-107) fibrils after 24 h of incubation with EGCG (Fig. 3A). OC immunoreactivity, turbidty, and sedimentation analysis also revealed that EGCG remodeled SEM1(45-107) fibrils, but as with PAP85-120 fibrils, remodeling assessed by these measures was only observed at 2 h or later (Fig. 3B-D). Examination by TEM revealed that EGCG-remodeled SEM1(45-107) products were very small oligomeric structures (Fig. 3E). Very similar observations were made with SEM2(49-107) fibrils, which were also rapidly remodeled by EGCG (Fig. 4A-E). These findings suggest that EGCG disrupts critical contacts that are required to maintain SEM1(45-107) and SEM2(49-107) fibrils.Fig. 3.

Bottom Line: Here, we confirm that the green tea polyphenol, epigallocatechin-3-gallate (EGCG), slowly remodels fibrils formed by PAP248-286 termed SEVI (semen derived enhancer of viral infection) and also exerts a direct anti-viral effect.We elucidate for the first time that EGCG remodels PAP85-120, SEM1(45-107), and SEM2(49-107) fibrils more rapidly than SEVI fibrils.The combined anti-amyloid and anti-viral properties of EGCG could have utility in preventing HIV transmission.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA Pharmacology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.

No MeSH data available.


Related in: MedlinePlus