scholarly journals Sulforaphane downregulated fatty acid synthase and inhibited microtubule-mediated mitophagy leading to apoptosis

2021 ◽  
Vol 12 (10) ◽  
Author(s):  
Yuting Yan ◽  
Yan Zhou ◽  
Juntao Li ◽  
Zhongnan Zheng ◽  
Yabin Hu ◽  
...  

AbstractWe previously demonstrated that sulforaphane (SFN) inhibited autophagy leading to apoptosis in human non-small cell lung cancer (NSCLC) cells, but the underlying subcellular mechanisms were unknown. Hereby, high-performance liquid chromatography-tandem mass spectrometry uncovered that SFN regulated the production of lipoproteins, and microtubule- and autophagy-associated proteins. Further, highly expressed fatty acid synthase (FASN) contributed to cancer malignancy and poor prognosis. Results showed that SFN depolymerized microtubules, downregulated FASN, and decreased its binding to α-tubulin; SFN downregulated FASN, acetyl CoA carboxylase (ACACA), and ATP citrate lyase (ACLY) via activating proteasomes and downregulating transcriptional factor SREBP1; SFN inhibited the interactions among α-tubulin and FASN, ACACA, and ACLY; SFN decreased the amount of intracellular fatty acid (FA) and mitochondrial phospholipids; and knockdown of FASN decreased mitochondrial membrane potential (ΔΨm) and increased reactive oxygen species, mitochondrial abnormality, and apoptosis. Further, SFN downregulated mitophagy-associated proteins Bnip3 and NIX, and upregulated mitochondrial LC3 II/I. Transmission electron microscopy showed mitochondrial abnormality and accumulation of mitophagosomes in response to SFN. Combined with mitophagy inducer CCCP or autophagosome–lysosome fusion inhibitor Bafilomycin A1, we found that SFN inhibited mitophagosome–lysosome fusion leading to mitophagosome accumulation. SFN reduced the interaction between NIX and LC3 II/I, and reversed CCCP-caused FA increase. Furthermore, knockdown of α-tubulin downregulated NIX and BNIP3 production, and upregulated LC3 II/I. Besides, SFN reduced the interaction and colocalization between α-tubulin and NIX. Thus, SFN might cause apoptosis via inhibiting microtubule-mediated mitophagy. These results might give us a new insight into the mechanisms of SFN-caused apoptosis in the subcellular level.

2020 ◽  
Vol 41 (6) ◽  
pp. 778-789 ◽  
Author(s):  
Su-Hyeong Kim ◽  
Eun-Ryeong Hahm ◽  
Krishna B Singh ◽  
Sruti Shiva ◽  
Jacob Stewart-Ornstein ◽  
...  

Abstract Withaferin A (WA) is a promising phytochemical exhibiting in vitro and in vivo anticancer activities against prostate and other cancers, but the mechanism of its action is not fully understood. In this study, we performed RNA-seq analysis using 22Rv1 human prostate cancer cell line to identify mechanistic targets of WA. Kyoto Encyclopedia of Genes and Genomes pathway analysis of the differentially expressed genes showed most significant enrichment of genes associated with metabolism. These results were validated using LNCaP and 22Rv1 human prostate cancer cells and Hi-Myc transgenic mice as models. The intracellular levels of acetyl-CoA, total free fatty acids and neutral lipids were decreased significantly following WA treatment in both cells, which was accompanied by downregulation of mRNA (confirmed by quantitative reverse transcription-polymerase chain reaction) and protein levels of key fatty acid synthesis enzymes, including ATP citrate lyase, acetyl-CoA carboxylase 1, fatty acid synthase and carnitine palmitoyltransferase 1A. Ectopic expression of c-Myc, but not constitutively active Akt, conferred a marked protection against WA-mediated suppression of acetyl-CoA carboxylase 1 and fatty acid synthase protein expression, and clonogenic cell survival. WA was a superior inhibitor of cell proliferation and fatty acid synthesis in comparison with known modulators of fatty acid metabolism including cerulenin and etomoxir. Intraperitoneal WA administration to Hi-Myc transgenic mice (0.1 mg/mouse, three times/week for 5 weeks) also resulted in a significant decrease in circulating levels of total free fatty acids and phospholipids, and expression of ATP citrate lyase, acetyl-CoA carboxylase 1, fatty acid synthase and carnitine palmitoyltransferase 1A proteins in the prostate in vivo.


2007 ◽  
Vol 282 (43) ◽  
pp. 31592-31600 ◽  
Author(s):  
Jamie W. Joseph ◽  
Matthew L. Odegaard ◽  
Sarah M. Ronnebaum ◽  
Shawn C. Burgess ◽  
Jeffrey Muehlbauer ◽  
...  

1993 ◽  
Vol 265 (2) ◽  
pp. L140-L147 ◽  
Author(s):  
Z. X. Xu ◽  
W. Stenzel ◽  
S. M. Sasic ◽  
D. A. Smart ◽  
S. A. Rooney

There are developmental and glucocorticoid-induced increases in the rate of fatty acid biosynthesis and in the activity of fatty acid synthase in late gestation fetal lung. We have now measured mRNA levels of fatty acid synthase and of two other enzymes of fatty acid biosynthesis, ATP citrate lyase and acetyl-CoA carboxylase, in developing fetal and postnatal rat lung and in fetal lung explants cultured with and without dexamethasone. There was a developmental increase in the mRNA for fatty acid synthase with the maximum level being reached on fetal day 21 (term is fetal day 22). This profile was similar to that reported for de novo fatty acid synthesis and fatty acid synthase activity. There was a similar but less pronounced developmental increase in the mRNA for ATP citrate lyase and a corresponding increase in its activity. There was no developmental change in the mRNA for acetyl-CoA carboxylase. Dexamethasone increased the level of fatty acid synthase mRNA approximately threefold but had no effect on those for ATP citrate lyase and acetyl-CoA carboxylase. The effect of dexamethasone on fatty acid synthase mRNA was rapid, biphasic, and partly inhibited by actinomycin D and cycloheximide. We conclude that glucocorticoids increase expression of the gene for fatty acid synthase in fetal lung. The effect of the hormone appears to be due to increased transcription and post-transcriptional events and is dependent on protein synthesis.


1989 ◽  
Vol 259 (3) ◽  
pp. 821-829 ◽  
Author(s):  
J L Evans ◽  
B Quistorff ◽  
L A Witters

The zonal distribution within rat liver of acetyl-CoA carboxylase, ATP citrate-lyase and fatty acid synthase, the principal enzymes of fatty acid synthesis, was investigated by using dual-digitonin-pulse perfusion. Analysis of enzyme mass by immunoblotting revealed that, in normally feeding male rats, the periportal/perivenous ratio of acetyl-CoA carboxylase mass was 1.9. The periportal/perivenous ratio of ATP citrate-lyase mass was 1.4, and fatty acid synthase exhibited the largest periportal/perivenous mass gradient, having a ratio of 3.1. This pattern of enzyme distribution was observed in male rats only; in females, the periportal/perivenous ratio of enzyme mass was nearly equal. The periportal/perivenous gradients for acetyl-CoA carboxylase, ATP citrate-lyase and fatty acid synthase observed in fed (and fasted) males were abolished when animals were fasted (48 h) and refed (30 h) with a high-carbohydrate/low-fat diet. As determined by enzyme assay of eluates obtained from the livers of normally feeding male rats, there is also periportal zonation of acetyl-CoA carboxylase activity, expressed either as units per mg of eluted protein or units per mg of acetyl-CoA carboxylase protein, suggesting the existence of gradients in both enzyme mass and specific activity. From these results, we conclude that the enzymes of fatty acid synthesis are zonated periportally in the liver of the normally feeding male rat.


2010 ◽  
Vol 61 (3) ◽  
pp. 463-468 ◽  
Author(s):  
Aidil Abdul Hamid ◽  
Noor Fatmawati Mokhtar ◽  
Ekhlass M. Taha ◽  
Othman Omar ◽  
Wan Mohtar Wan Yusoff

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Zeynep Tuzcu ◽  
Cemal Orhan ◽  
Nurhan Sahin ◽  
Kazim Sahin ◽  
Vijaya Juturu

Objectives: CNM (CNM) polyphenol has antioxidant and anti-inflammatory properties. Therefore, we hypothesized CNM decrease heart disease risk factors and may enhance anti- inflammatory properties in rats fed a diet containing CNM. In this study, we evaluated the effects of CNM polyphenol on insulin resistance (IR), hyperlipidemia, hepatic transcription factors expressions [sterol regulatory element-binding protein1c (SREBP-1c), liver X receptor-α (LXR-α), nuclear factor kappa B p65 (NF-κB p65), nuclear factor-E2-related factor-2 (Nrf2)] in rats fed high fat diet (HFD). Method: Twenty-eight Wistar rats were allocated into four groups; (i) normal control; animals fed with normal chow (C ) (ii) CNM (C+CNM 100 mg/kg b.wt.), (iii) HFD (42% of calories as fat, high fat diet [HFD]), and (iv) HFD + CNM for 12 weeks. Blood analysis for triglycerides (TG) and cholesterol (CHOL), glucose, insulin, malonaldehyde (MDA a marker of oxidative stress [OS]) were estimated. Body weight, visceral fat and liver weight recorded and liver MDA assessed. SREBP-1c, LXR-α, ATP-citrate lyase (ACLY), fatty acid synthase (FAS), NF-κB p65 expressions and decreased the PPAR-α, p-IRS-1, Nrf2, HO-1 proteins were evaluated by Western blotting. Results: HFD rats of the liver had increased SREBP-1c, LXR-α, ATP-citrate lyase (ACLY), fatty acid synthase (FAS), NF-κB p65 expressions and decreased the PPAR-α, p-IRS-1, Nrf2, HO-1 expressions compared to control group. CNM supplementation decreased body weight (8.4%), visceral fat (36.6%), liver weight (17.7%), serum glucose and insulin concentrations, lipid profile ( P < 0.05), and serum and liver MDA (23.3% and 25.4 %) concentration compared to HFD rats ( P < 0.05). CNM decreased hepatic SREBP-1c (18.1 %), LXRα (27.9%), ATP-citrate lyase (ACLY, 22.7 %), fatty acid synthase (FAS, 15.8 %), NF-κB p65 (23.3%) and enhanced the PPAR-α, IRS-1 (72.7 %), Nrf2 (111.7 %) and HO-1 (72.1 %) proteins in HFD rat livers ( P < 0.05). Discussion: These results suggest CNM supplementation reduces hyperlipidemia, inflammation, and oxidative stress through activating transcription factors (SREBP-1c, LXR-α, NF-κB, and Nrf2) and anti-oxidative defense signaling pathway.


1993 ◽  
Vol 295 (1) ◽  
pp. 61-66 ◽  
Author(s):  
M M Awan ◽  
E D Saggerson

1. Viable myocytes were obtained from rat hearts. Oxidation of [1-14C]palmitate by these cells could be decreased by the addition of glucose (5 mM) or lactate (2 mM). In the presence of glucose, insulin decreased and adrenaline increased palmitate oxidation. 2. The myocytes contained activities of ATP citrate-lyase, acetyl-CoA carboxylase and the condensing enzyme of the fatty acid elongation system. No fatty acid synthase activity was demonstrable in myocytes. 3. In rat hearts perfused with 5 mM glucose, malonyl-CoA content was acutely raised by insulin. In the presence of glucose+insulin, perfusion with palmitate or adrenaline decreased the malonyl-CoA content. 4. It is concluded that malonyl-CoA can be synthesized within cardiac myocytes and that the level of this metabolite can be acutely regulated. This is likely to have consequences for the regulation of carnitine palmitoyltransferase in the heart.


1983 ◽  
Vol 3 (11) ◽  
pp. 1063-1070 ◽  
Author(s):  
T. Norman Palmer ◽  
Margaret A. Caldecourt ◽  
David I. Watts ◽  
Mary C. Sugden

Vasopressin and angiotensin II inhibited lipogenesis (measured with 3H2O) in hepatocytes from fed rats. Inhibition was also observed with hepatocytes from fed rats which had been depleted of glycogen in vitro and incubated with lactate + pyruvate (5 mM + 0.5 mM) as substrates. The inhibitory actions of the hormones are therefore independent of hormone-mediated changes in glycogenolytic or glycolytic flux from glycogen, and thus the site(s) of hormone action must be subsequent to the formation of lactate. (-)Hydroxycitrate, a specific inhibitor of ATP-citrate lyase, decreased lipogenesis in hepatocytes from fed rats incubated with lactate + pyruvate by approx. 51% but had little effect on lipogenesis in glycogen-depleted hepatocytes similarly incubated. There was parallel inhibition of incorporation of 14C from [U-14C]lactate into fatty acid and lipogenesis as measured with 3H2O in each case. Thus depletion of glycogen, or conceivably the process of glycogen-depletion (incubation with dibutyryl cyclic AMP) causes a change in the rate-determining step(s) for lipogenesis from lactate. Vasopressin and angiotensin II also decreased lipogenesis and incorporation of 14C into fatty acids in glycogen-depleted hepatocytes provided with [U-14C]proline as opposed to [U-14C]-lactate. However, proline-stimulated lipogenesis was inhibited by (-)hydroxycitrate, and proline-stimulated lipogenesis and incorporation of 14C from [U-14C]-proline were not decreased in parallel by this inhibitor (inhibition of 52% and 85% respectively). It is inferred that lactate and proline stimulate lipogenesis by different mechanisms and incorporation of 14C from [U-14C]proline and [U-14C]lactate into fatty acid occurs via different routes. (-)Hydroxycitrate diminished the inhibitory effects of the hormones in the presence of either lactate or proline, suggesting that flux through ATP-citrate lyase is important for the hormone response.


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