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Foam cell-derived 4-hydroxynonenal induces endothelial cell senescence in a TXNIP-dependent manner.

Riahi Y, Kaiser N, Cohen G, Abd-Elrahman I, Blum G, Shapira OM, Koler T, Simionescu M, Sima AV, Zarkovic N, Zarkovic K, Orioli M, Aldini G, Cerasi E, Leibowitz G, Sasson S - J. Cell. Mol. Med. (2015)

Bottom Line: Previous studies showed that peroxisome proliferator-activated receptor (PPAR)δ was activated by 4-hydroalkenals, such as 4-HNE.Pharmacological interventions supported the involvement of the 4-HNE-PPARδ axis in the induction of TXNIP and VEC senescence.The association of TXNIP with VEC senescence was further supported by immunofluorescent staining of human carotid plaques in which the expression of both TXNIP and p21 was augmented in endothelial cells.

View Article: PubMed Central - PubMed

Affiliation: Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University, Jerusalem, Israel.

No MeSH data available.


Related in: MedlinePlus

The role of TXNIP in VEC senescence. (A) TXNIP expression in VEC at different passages was analysed by Western blot. P < 0.07, for differences from cells at passage 8 (n = 3). (B) VEC were transfected with the hTXNIP-lacZ expression plasmid or with an empty vector. Cells were then harvested and taken for Western blot analysis of TXNIP and senescence markers; results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from cells transfected with the empty vector. (C) VEC cultures were treated with the indicated concentrations of 4-HNE for 3 days, with a daily change of medium. Cell lysates were prepared and used for Western blot analysis of TXNIP. The level of TXNIP in untreated controls was taken as 100%. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control. (D) VEC co-cultured with THP-1 macrophages (M) or foam cells (FC) as described above, and analysed for TXNIP expression. TXNIP expression levels in the VEC + M group was taken as 100%. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control groups. (E) VEC co-cultured with foam cells (FC) in the absence (control) or presence of 10 mM FL-926-A16, as described under the legend to Figure3, and analysed for TXNIP expression. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control groups. (F) VEC were transfected with TXNIP siRNA and taken 24 hrs later for co-culture with foam cells (FC) for additional 72 hrs. VEC were then lysed and taken for Western blot analysis of TXNIP or of the senescence markers. The level of TXNIP and the senescence markers in untransfected controls was taken as 100%. Representative Western blots quantification of TXNIP and of various senescence markers are shown. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from respective controls (n = 3).
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fig04: The role of TXNIP in VEC senescence. (A) TXNIP expression in VEC at different passages was analysed by Western blot. P < 0.07, for differences from cells at passage 8 (n = 3). (B) VEC were transfected with the hTXNIP-lacZ expression plasmid or with an empty vector. Cells were then harvested and taken for Western blot analysis of TXNIP and senescence markers; results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from cells transfected with the empty vector. (C) VEC cultures were treated with the indicated concentrations of 4-HNE for 3 days, with a daily change of medium. Cell lysates were prepared and used for Western blot analysis of TXNIP. The level of TXNIP in untreated controls was taken as 100%. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control. (D) VEC co-cultured with THP-1 macrophages (M) or foam cells (FC) as described above, and analysed for TXNIP expression. TXNIP expression levels in the VEC + M group was taken as 100%. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control groups. (E) VEC co-cultured with foam cells (FC) in the absence (control) or presence of 10 mM FL-926-A16, as described under the legend to Figure3, and analysed for TXNIP expression. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control groups. (F) VEC were transfected with TXNIP siRNA and taken 24 hrs later for co-culture with foam cells (FC) for additional 72 hrs. VEC were then lysed and taken for Western blot analysis of TXNIP or of the senescence markers. The level of TXNIP and the senescence markers in untransfected controls was taken as 100%. Representative Western blots quantification of TXNIP and of various senescence markers are shown. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from respective controls (n = 3).

Mentions: It has been suggested that increased TRX activity protects VEC from atherogenesis 59. TXNIP, the natural inhibitor of TRX, plays a prominent role in regulating TRX activity in VEC; high TXNIP levels were associated with endothelial cell dysfunction 49,50,60. Figure4A suggests the involvement of TXNIP in passage-induced replicative senescence in VEC. Indeed, overexpression of TXNIP in low passaged VEC cultures (transfected with the hTXNIP-lacZ expression plasmid) augmented the expression of p21 and reduced p-pRB levels (Fig.4B). Next, we studied the effect of exogenously added 4-HNE on TXNIP expression and its impact on oxidative stress-induced senescence and found increased TXNIP expression in VEC incubated with 10 μM 4-HNE for 7 days (Fig.4C). Importantly, TXNIP expression was increased in VEC co-cultured with foam-cells (Fig.4D). The 4-HNE scavenger FL-926-A16 decreased TXNIP expression in VEC co-cultured with foam cells (Fig.4E), supporting the hypothesis that lipid peroxidation products are involved in the up-regulation of TXNIP expression. Noteworthy, silencing of TXNIP in VEC co-cultured with foam cells prevented the induction of the senescence markers (Fig.4F). Scrambled RNA sequences had no influence on TXNIP and senescence marker expression (Fig. S3). Collectively, these results suggest that 4-HNE up-regulates TXNIP expression and support a role for the latter in both replicative and stress-induced senescence in VEC.


Foam cell-derived 4-hydroxynonenal induces endothelial cell senescence in a TXNIP-dependent manner.

Riahi Y, Kaiser N, Cohen G, Abd-Elrahman I, Blum G, Shapira OM, Koler T, Simionescu M, Sima AV, Zarkovic N, Zarkovic K, Orioli M, Aldini G, Cerasi E, Leibowitz G, Sasson S - J. Cell. Mol. Med. (2015)

The role of TXNIP in VEC senescence. (A) TXNIP expression in VEC at different passages was analysed by Western blot. P < 0.07, for differences from cells at passage 8 (n = 3). (B) VEC were transfected with the hTXNIP-lacZ expression plasmid or with an empty vector. Cells were then harvested and taken for Western blot analysis of TXNIP and senescence markers; results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from cells transfected with the empty vector. (C) VEC cultures were treated with the indicated concentrations of 4-HNE for 3 days, with a daily change of medium. Cell lysates were prepared and used for Western blot analysis of TXNIP. The level of TXNIP in untreated controls was taken as 100%. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control. (D) VEC co-cultured with THP-1 macrophages (M) or foam cells (FC) as described above, and analysed for TXNIP expression. TXNIP expression levels in the VEC + M group was taken as 100%. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control groups. (E) VEC co-cultured with foam cells (FC) in the absence (control) or presence of 10 mM FL-926-A16, as described under the legend to Figure3, and analysed for TXNIP expression. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control groups. (F) VEC were transfected with TXNIP siRNA and taken 24 hrs later for co-culture with foam cells (FC) for additional 72 hrs. VEC were then lysed and taken for Western blot analysis of TXNIP or of the senescence markers. The level of TXNIP and the senescence markers in untransfected controls was taken as 100%. Representative Western blots quantification of TXNIP and of various senescence markers are shown. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from respective controls (n = 3).
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fig04: The role of TXNIP in VEC senescence. (A) TXNIP expression in VEC at different passages was analysed by Western blot. P < 0.07, for differences from cells at passage 8 (n = 3). (B) VEC were transfected with the hTXNIP-lacZ expression plasmid or with an empty vector. Cells were then harvested and taken for Western blot analysis of TXNIP and senescence markers; results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from cells transfected with the empty vector. (C) VEC cultures were treated with the indicated concentrations of 4-HNE for 3 days, with a daily change of medium. Cell lysates were prepared and used for Western blot analysis of TXNIP. The level of TXNIP in untreated controls was taken as 100%. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control. (D) VEC co-cultured with THP-1 macrophages (M) or foam cells (FC) as described above, and analysed for TXNIP expression. TXNIP expression levels in the VEC + M group was taken as 100%. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control groups. (E) VEC co-cultured with foam cells (FC) in the absence (control) or presence of 10 mM FL-926-A16, as described under the legend to Figure3, and analysed for TXNIP expression. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from the control groups. (F) VEC were transfected with TXNIP siRNA and taken 24 hrs later for co-culture with foam cells (FC) for additional 72 hrs. VEC were then lysed and taken for Western blot analysis of TXNIP or of the senescence markers. The level of TXNIP and the senescence markers in untransfected controls was taken as 100%. Representative Western blots quantification of TXNIP and of various senescence markers are shown. Results are expressed as mean ± SEM, n = 3; *P < 0.05 for differences from respective controls (n = 3).
Mentions: It has been suggested that increased TRX activity protects VEC from atherogenesis 59. TXNIP, the natural inhibitor of TRX, plays a prominent role in regulating TRX activity in VEC; high TXNIP levels were associated with endothelial cell dysfunction 49,50,60. Figure4A suggests the involvement of TXNIP in passage-induced replicative senescence in VEC. Indeed, overexpression of TXNIP in low passaged VEC cultures (transfected with the hTXNIP-lacZ expression plasmid) augmented the expression of p21 and reduced p-pRB levels (Fig.4B). Next, we studied the effect of exogenously added 4-HNE on TXNIP expression and its impact on oxidative stress-induced senescence and found increased TXNIP expression in VEC incubated with 10 μM 4-HNE for 7 days (Fig.4C). Importantly, TXNIP expression was increased in VEC co-cultured with foam-cells (Fig.4D). The 4-HNE scavenger FL-926-A16 decreased TXNIP expression in VEC co-cultured with foam cells (Fig.4E), supporting the hypothesis that lipid peroxidation products are involved in the up-regulation of TXNIP expression. Noteworthy, silencing of TXNIP in VEC co-cultured with foam cells prevented the induction of the senescence markers (Fig.4F). Scrambled RNA sequences had no influence on TXNIP and senescence marker expression (Fig. S3). Collectively, these results suggest that 4-HNE up-regulates TXNIP expression and support a role for the latter in both replicative and stress-induced senescence in VEC.

Bottom Line: Previous studies showed that peroxisome proliferator-activated receptor (PPAR)δ was activated by 4-hydroalkenals, such as 4-HNE.Pharmacological interventions supported the involvement of the 4-HNE-PPARδ axis in the induction of TXNIP and VEC senescence.The association of TXNIP with VEC senescence was further supported by immunofluorescent staining of human carotid plaques in which the expression of both TXNIP and p21 was augmented in endothelial cells.

View Article: PubMed Central - PubMed

Affiliation: Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University, Jerusalem, Israel.

No MeSH data available.


Related in: MedlinePlus