Anna Bielak

Dr. Anna Bielak

orcid

Research Focus & Metrics

Academic Career Length

30Years (1997-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
3 March 2017 in Biogerontology
Verified
Journal Article
Open access
PDF file
WGWioleta Grabowska
Wioleta Grabowska
ESEwa Sikora
Ewa Sikora
ABAnna Bielak
Anna Bielak
Ageing is a plastic process and can be successfully modulated by some biomedical approaches or pharmaceutics. In this manner it is possible to delay or even prevent some age-related pathologies. There are some defined interventions, which give promising results in animal models or even in human studies, resulting in lifespan elongation or healthspan improvement. One of the most promising targets for anti-ageing approaches are proteins belonging to the sirtuin family. Sirtuins were originally discovered as transcription repressors in yeast, however, nowadays they are known to occur in bacteria and eukaryotes (including mammals). In humans the family consists of seven members (SIRT1-7) that possess either mono-ADP ribosyltransferase or deacetylase activity. It is believed that sirtuins play key role during cell response to a variety of stresses, such as oxidative or genotoxic stress and are crucial for cell metabolism. Although some data put in question direct involvement of sirtuins in extending human lifespan, it was documented that proper lifestyle including physical activity and diet can influence healthspan via increasing the level of sirtuins. The search for an activator of sirtuins is one of the most extensive and robust topic of research. Some hopes are put on natural compounds, including curcumin. In this review we summarize the involvement and usefulness of sirtuins in anti-ageing interventions and discuss the potential role of curcumin in sirtuins regulation.

16 November 2013 in Biogerontology
Verified
Journal Article
Open access
PDF file
ABAnna Bielak
Anna Bielak
Maciej WnukMaciej Wnuk
Maciej Wnuk
DPDorota Przybylska
Dorota Przybylska
WGWioleta Grabowska
Wioleta Grabowska
ALAnna Lewinska
Anna Lewinska
ESEwa Sikora
Ewa Sikora
Senescence of vascular smooth muscle cells (VSMCs) contributes to aging as well as age-related diseases of the cardiovascular system. Senescent VSMCs have been shown to be present in atherosclerotic plaques. Both replicative (RS) and stress-induced premature senescence (SIPS) accompany cardiovascular diseases. We aimed to establish the signature of RS and SIPS of VSMCs, induced by a common anticancer drug, doxorubicin, and to discover the so far undisclosed features of senescent cells that are potentially harmful to the organism. Most of the senescence hallmarks were common for both RS and SIPS; however, some differences were observed. 32 % of doxorubicin-treated cells were arrested in the G2/M phase of the cell cycle, while 73 % of replicatively senescing cells were arrested in the G1 phase. Moreover, on the basis of alkaline phosphatase activity measurements, we show that a 7-day treatment with doxorubicin (dox), does not cause precocious cell calcification, which is a characteristic feature of RS. We did not observe calcification even though after 7 days of dox-treatment many other markers characteristic for senescent cells were present. It can suggest that dox-induced SIPS does not accelerate the mineralization of vessels. We consider that detailed characterization of the two types of cellular senescence can be useful in in vitro studies of potential anti-aging factors.

Verified
Journal Article
Open access
PDF file
ABAnna Bielak
Anna Bielak
WGWioleta Grabowska
Wioleta Grabowska
AGAgata Głuchowska
Agata Głuchowska
Agnieszka BojkoAgnieszka Bojko
Agnieszka Bojko
GMGrazyna Mosieniak
Grazyna Mosieniak
ESEwa Sikora
Ewa Sikora
It is believed that postponing ageing is more effective and less expensive than the treatment of particular age-related diseases. Compounds which could delay symptoms of ageing, especially natural products present in a daily diet, are intensively studied. One of them is curcumin. It causes the elongation of the lifespan of model organisms, alleviates ageing symptoms and postpones the progression of age-related diseases in which cellular senescence is directly involved. It has been demonstrated that the elimination of senescent cells significantly improves the quality of life of mice. There is a continuous search for compounds, named senolytic drugs, that selectively eliminate senescent cells from organisms. In this paper, we endeavor to review the current knowledge about the anti-ageing role of curcumin and discuss its senolytic potential.

26 August 2019 in Toxins
Verified
Journal Article
Open access
PDF file
KJKinga Jaworska
Kinga Jaworska
DHDagmara Hering
Dagmara Hering
GMGrazyna Mosieniak
Grazyna Mosieniak
ABAnna Bielak
Anna Bielak
MPMarta Pilz
Marta Pilz
MUMarcin Ufnal
Marcin Ufnal
Trimethylamine-N-oxide (TMAO) has been suggested as a marker and mediator of cardiovascular diseases. However, data are contradictory, and the mechanisms are obscure. Strikingly, the role of the TMAO precursor trimethylamine (TMA) has not drawn attention in cardiovascular studies even though toxic effects of TMA were proposed several decades ago. We assessed plasma TMA and TMAO levels in healthy humans (HH) and cardiovascular patients qualified for aortic valve replacement (CP). The cytotoxicity of TMA and TMAO in rat cardiomyocytes was evaluated using an MTT test. The effects of TMA and TMAO on albumin and lactate dehydrogenase (LDH) were assessed using fluorescence correlation spectroscopy. In comparison to HH, CP had a two-fold higher plasma TMA (p < 0.001) and a trend towards higher plasma TMAO (p = 0.07). In CP plasma, TMA was inversely correlated with an estimated glomerular filtration rate (eGFR, p = 0.002). TMA but not TMAO reduced cardiomyocytes viability. Incubation with TMA but not TMAO resulted in the degradation of the protein structure of LDH and albumin. In conclusion, CP show increased plasma TMA, which is inversely correlated with eGFR. TMA but not TMAO exerts negative effects on cardiomyocytes, likely due to its disturbing effect on proteins. Therefore, TMA but not TMAO may be a toxin and a marker of cardiovascular risk.

1 October 1997 in Biochemical Pharmacology
Verified
Journal Article
Closed access
ESEwa Sikora
Ewa Sikora
ABAnna Bielak
Anna Bielak
KPKatarzyna Piwocka
Katarzyna Piwocka
SJSkierski Janusz
Skierski Janusz
EREwa Radziszewska
Ewa Radziszewska

18 December 2013 in Current Vascular Pharmacology
Verified
Journal Article
Closed access
PDF file
ESEwa Sikora
Ewa Sikora
ABAnna Bielak
Anna Bielak
GMGrazyna Mosieniak
Grazyna Mosieniak
Cellular senescence is the state of permanent inhibition of cell proliferation. Senescent cells are characterized by several features including increased activity of senescence-associated β-galactosidase (SA-β-GAL) and senescenceassociated secretory phenotype (SASP). In vitro, 2 types of senescence have been described. One is telomere-dependent replicative senescence and the second is stress-induced premature senescence (SIPS). Despite some tissue-specific characteristics many kinds of cells, including stem/progenitor cells, can undergo senescence both in vitro and in vivo. Senescent cells were detected in murine, primate and human tissues using different markers. There is mounting evidence that senescent cells contribute to ageing and age-related disease by generating a low grade inflammation state (senescenceassociated secretory phenotype-SASP). Even though cellular senescence is a barrier for cancer it can, paradoxically, stimulate development of cancer via proinflammatory cytokines. There is evidence that senescent vascular cells, both endothelial and smooth muscle cells, participate in atherosclerosis and senescent preadipocytes and adipocytes have been shown to lead to insulin resistance. Thus, modulation of cellular senescence is considered as a potential pro-longevity strategy. This can be achieved by: elimination of selected senescent cells, epigenetic reprogramming of senescent cells, preventing cellular senescence or influencing the secretory phenotype. Some pharmacological interventions have already shown promising results.