Athanasios Karpouzos

Dr. Athanasios Karpouzos


Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

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

Representative Publications

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Verified
Journal Article
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Charalampos VorosCharalampos Voros
Charalampos Voros
FCFotios Chatzinikolaou
Fotios Chatzinikolaou
GPGeorgios Papadimas
Georgios Papadimas
SPSpyridon Polykalas
Spyridon Polykalas
DMDespoina Mavrogianni
Despoina Mavrogianni
George DaskalakisGeorge Daskalakis
George Daskalakis
The functional deterioration of granulosa cells (GCs), essential for follicular growth, steroidogenesis, and oocyte competence, indicates ovarian aging and reduced fertility. An expanding corpus of research indicates that oxidative stress is a primary molecular contributor to granulosa cell dysfunction, culminating in mitochondrial impairment, reduced metabolic support for oocytes, and the activation of regulated apoptotic pathways that end in follicular atresia. Ferroptosis, an emergent type of iron-dependent lipid peroxidation, has been identified as a crucial mechanism contributing to chemotherapy-induced ovarian insufficiency, polycystic ovary syndrome (PCOS), and granulosa cell death in aging ovaries, in addition to conventional apoptosis. The SIRT1-Nrf2 axis acts as a crucial anti-oxidative and anti-ferroptotic system that protects GC viability, maintains mitochondrial homeostasis, and upholds redox equilibrium. SIRT1 promotes mitochondrial biogenesis and metabolic resilience by deacetylating downstream proteins, including FOXO3 and PGC-1α. Nrf2 simultaneously controls the transcriptional activation of detoxifying and antioxidant enzymes, including HO-1, SOD2, NQO1, and GPX4, which are critical inhibitors of ferroptosis. Disruption of SIRT1-Nrf2 signalling accelerates GC senescence, follicular depletion, and reproductive aging. In contrast, pharmaceutical and nutraceutical therapies, including metformin, melatonin, resveratrol, and agents that increase NAD+ levels, may reverse ovarian deterioration and reactivate SIRT1-Nrf2 activity. This narrative review highlights innovative treatment prospects for ovarian aging, fertility preservation, and assisted reproduction by synthesising current evidence on ferroptotic pathways, SIRT1-Nrf2 interactions, and oxidative stress in granulosa cells. An understanding of these interrelated biological networks enables the development of tailored therapies that postpone ovarian ageing and enhance reproductive outcomes for women receiving fertility therapy.

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Journal Article
Open access
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Charalampos VorosCharalampos Voros
Charalampos Voros
FCFotios Chatzinikolaou
Fotios Chatzinikolaou
Ioannis K. PapapanagiotouIoannis K. Papapanagiotou
Ioannis K. Papapanagiotou
SPSpyridon Polykalas
Spyridon Polykalas
DMDespoina Mavrogianni
Despoina Mavrogianni
George DaskalakisGeorge Daskalakis
George Daskalakis
Women of reproductive age, especially those with polycystic ovarian syndrome (PCOS), often use glucagon-like peptide-1 receptor agonists (GLP-1RAs) to improve their metabolic functions. A growing body of evidence suggests that GLP-1R signaling may directly affect ovarian physiology, influencing granulosa cell proliferation, survival pathways, and steroidogenic production, in addition to its systemic metabolic effects. Nonetheless, there is a limited comprehension of the molecular mechanisms that regulate these activities and their correlation with menstrual function, reproductive potential, and assisted reproduction. This comprehensive review focuses on ovarian biology, granulosa cell signaling networks, steroidogenesis, and translational fertility outcomes, integrating clinical, in vivo, and in vitro information to elucidate the effects of GLP-1 receptor agonists on reproductive health. We conducted a thorough search of PubMed, Scopus, and Web of Science for randomized trials, prospective studies, animal models, and cellular experiments evaluating the effects of GLP-1RA on reproductive or ovarian outcomes, in accordance with PRISMA criteria. The retrieved data included metabolic changes, androgen levels, monthly regularity, ovarian structure, granulosa cell growth and death, FOXO1 signaling, FSH-cAMP-BMP pathway activity, and fertility or IVF results. Clinical trials shown that GLP-1 receptor agonists improve menstrual regularity, decrease body weight and central adiposity, increase sex hormone-binding globulin levels, and lower free testosterone in overweight and obese women with PCOS. Liraglutide, when combined with metformin, significantly improved IVF pregnancy rates, whereas exenatide increased natural conception rates. Mechanistic studies demonstrate that GLP-1R activation affects FOXO1 phosphorylation, hence promoting granulosa cell proliferation and anti-apoptotic processes. Incretin signaling altered steroidogenesis by reducing the levels of StAR, P450scc, and 3β-HSD, so inhibiting FSH-induced progesterone synthesis, while simultaneously enhancing BMP-Smad signaling. Animal studies demonstrated both beneficial (enhanced follicular growth, anti-apoptotic effects) and detrimental results (oxidative stress, granulosa cell death, uterine inflammation), indicating a context- and dose-dependent response. GLP-1 receptor agonists influence female reproductive biology by altering overall physiological processes and specifically impacting the ovaries via FOXO1 regulation, steroidogenic enzyme expression, and BMP-mediated FSH signaling. Preliminary clinical data indicate improved reproductive function in PCOS, as seen by increased pregnancy rates in both natural and IVF cycles; nevertheless, animal studies reveal a potential risk of ovarian and endometrial damage. These results highlight the need for controlled human research to clarify reproductive safety, molecular pathways, and optimum therapy timing, particularly in non-PCOS patients and IVF settings.

20 November 2024 in Medicina
Verified
Journal Article
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SSSofoklis Stavros
Sofoklis Stavros
Anastasios PotirisAnastasios Potiris
Anastasios Potiris
AGAngeliki Gerede
Angeliki Gerede
AZAthanasios Zikopoulos
Athanasios Zikopoulos
MGMaria Giourga
Maria Giourga
EDEkaterini Domali
Ekaterini Domali
Background and Objectives: Caesarean scar pregnancy (CSP) is a rare form of ectopic pregnancy in which the early pregnancy implants at the site of the uterine scar. Methotrexate (MTX) in lower doses can be used to treat CSPs. However, MTX administration is associated with a spectrum of side effects that include hematological toxicities. This case report presents a CSP treated with an intragestational injection of MTX and subsequently developed pancytopenia. Materials and Methods: A 23-year-old woman at six weeks and six days of pregnancy was referred as a potential case of CSP. After establishing the diagnosis, she was treated with a transvaginal ultrasound-guided intragestational administration of 80 mg MTX (adjusted to 50 mg/m2 body surface area) under sedation. Results: On day four after the MTX injection, she developed oral ulcers, fever, and pruritic phlyctenular maculopapular rash. Subsequently, the patient developed febrile neutropenia and was admitted to the Intensive Care Unit. On day six, a subsequent exacerbation of the rash was observed with the formation of blisters and purplish spots with concurrent odynophagia and sialorrhea. Ultimately, the patient developed pancytopenia due to bone marrow suppression. Fifteen days after MTX administration, the patient recovered and was discharged from the hospital hemodynamically stable, afebrile, with dropping β-hcg levels, and in good clinical condition. Conclusions: Although methotrexate administration is the preferred option for the treatment of cesarean scar pregnancies, clinicians should be aware of the fact that its use entails potential risks, even when it is used locally. To our knowledge, this case is the first description of pancytopenia due to bone marrow suppression following a single low dose of intragestational methotrexate injection.

Verified
Journal Article
Open access
PDF file
Charalampos VorosCharalampos Voros
Charalampos Voros
FCFotios Chatzinikolaou
Fotios Chatzinikolaou
GPGeorgios Papadimas
Georgios Papadimas
AGAli Can Gunes
Ali Can Gunes
AKARISTOTELIS-MARIOS KOULAKMANIDIS
ARISTOTELIS-MARIOS KOULAKMANIDIS
George DaskalakisGeorge Daskalakis
George Daskalakis
Infertility and ovarian ageing are increasingly acknowledged as illnesses affected not just by endocrine decline but also by chronic inflammatory stress and mitochondrial dysfunction in the reproductive milieu. The cGAS-STING signalling pathway has emerged as a significant possibility linking these activities. The cGAS-STING pathway, originally defined as a cytosolic DNA-sensing mechanism essential for innate immune defence, is now recognised as a broader modulator of sterile inflammation, cellular senescence, and tissue failure. Experimental reproductive models suggest that the activation of this system may operate as a crucial link between mitochondrial dysfunction, cytosolic DNA accumulation, inflammatory cytokine production, and the progressive decline of ovarian and endometrial function. The activation of cGAS-STING in granulosa cells has been associated with inflammatory signalling and impaired steroidogenic activity.

Verified
Journal Article
Open access
PDF file
Charalampos VorosCharalampos Voros
Charalampos Voros
FCFotios Chatzinikolaou
Fotios Chatzinikolaou
GPGeorgios Papadimas
Georgios Papadimas
Ioannis K. PapapanagiotouIoannis K. Papapanagiotou
Ioannis K. Papapanagiotou
AKARISTOTELIS-MARIOS KOULAKMANIDIS
ARISTOTELIS-MARIOS KOULAKMANIDIS
George DaskalakisGeorge Daskalakis
George Daskalakis
Female reproductive aging is associated with a progressive decline in oocyte competence and reduced success in assisted reproductive technologies. While chromosomal abnormalities, mitochondrial dysfunction, and DNA damage have been extensively studied, these mechanisms do not fully explain developmental arrest in chromosomally euploid embryos or the variability in embryo competence. Human oocytes enter a transcriptionally quiescent state during meiotic maturation and rely almost entirely on the regulated translation of stored maternal messenger RNAs to support fertilization and early embryonic development until zygotic genome activation. In this context, translational fidelity becomes a critical determinant of proteome integrity and cellular function. Age-related alterations affecting ribosomal RNA integrity, transfer RNA modification, aminoacylation accuracy, and translational regulatory networks may impair the precision, timing, and coordination of protein synthesis. These defects can disrupt essential processes such as spindle assembly, cytoskeletal organization, and early cleavage dynamics, ultimately compromising embryo viability despite chromosomal normality. In addition, the follicular microenvironment, including redox balance, metabolic support, and signaling pathways, plays a crucial upstream role in maintaining translational integrity. This review integrates mechanistic evidence from molecular, cellular, and developmental studies to propose that progressive decline in translational fidelity represents a fundamental and previously underrecognized driver of reproductive aging. Understanding translational control as a central regulator of oocyte competence may provide new insights into unexplained IVF failure and support the development of novel biomarkers and therapeutic strategies aimed at preserving reproductive potential.

Verified
Journal Article
Open access
PDF file
Charalampos VorosCharalampos Voros
Charalampos Voros
FCFotios Chatzinikolaou
Fotios Chatzinikolaou
GPGeorgios Papadimas
Georgios Papadimas
Ioannis K. PapapanagiotouIoannis K. Papapanagiotou
Ioannis K. Papapanagiotou
AKAthanasios Karpouzos
Athanasios Karpouzos
George DaskalakisGeorge Daskalakis
George Daskalakis
Oocyte competency is a crucial determinant of fertilisation success and the initial development of embryos in assisted reproductive technologies. The metabolic and biochemical environment of the ovarian follicle is crucial for determining oocyte developmental potential, alongside genetic integrity. The follicular microenvironment includes a complex network of signalling chemicals that regulate mitochondrial activity, steroidogenesis, oxidative balance, and cellular energy metabolism. Recently, metabolic hormones originating from adipose tissue and skeletal muscle, namely, adipokines and myokines, have received considerable focus as crucial regulators of ovarian physiology. Adiponectin, irisin, and the recently identified hormone asprosin have emerged as crucial metabolic regulators influencing granulosa cell activity, mitochondrial bioenergetics, insulin signalling pathways, and redox homeostasis inside the follicular niche. Adiponectin mostly provides metabolic protection by activating AMP-activated protein kinase (AMPK) and improving insulin sensitivity, which in turn enhances mitochondrial efficiency and steroidogenic function in granulosa cells. Irisin, derived from the breakdown of fibronectin type III domain-containing protein 5 (FNDC5), aids the developing oocyte by facilitating mitochondrial biogenesis, augmenting oxidative phosphorylation, and altering cellular defence mechanisms against oxidative stress. Conversely, asprosin has been associated with glucogenic signalling, metabolic stress, and probable mitochondrial malfunction, suggesting a possible relationship between systemic metabolic problems and negative reproductive consequences. Clinical and experimental research indicate that the levels of these metabolic regulators in follicular fluid may correlate with ovarian response, oocyte quality, fertilisation rates, and embryo development during in vitro fertilisation cycles. This review consolidates current molecular, cellular, and clinical information, clarifying the pathways by which adipokines and myokines influence follicular metabolism and impact oocyte competency. Understanding the metabolic connections between systemic endocrine signals and the follicular milieu may provide novel indicators for reproductive prognosis and provide new treatment targets to improve assisted reproduction outcomes.