Aris Kaltsas

Prof. Aris Kaltsas

Third Department of Urology, Attikon University Hospital, School of Medicine,, National and Kapodistrian University of Athens, Athens, Attikí, Greece
orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

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

Representative Publications

View All Publications
4 October 2023 in Medicina
Verified
Journal Article
Open access
PDF file
Aris KaltsasAris Kaltsas
Aris Kaltsas
Oxidative stress is a significant factor in male infertility, compromising sperm function and overall reproductive health. As male infertility garners increasing attention, effective therapeutic interventions become paramount. This review investigates the therapeutic role of antioxidants in addressing male infertility. A detailed examination was conducted on antioxidants such as vitamin C, E, B12, D, coenzyme Q10, zinc, folic acid, selenium, l-carnitine, l-arginine, inositols, and alpha-lipoic acid. This analysis examines the methodologies, outcomes, and constraints of current clinical studies. Antioxidants show notable potential in counteracting the negative effects of oxidative stress on sperm. Based on the evidence, these antioxidants, individually or synergistically, can enhance sperm health and reproductive outcomes. However, certain limitations in the studies call for careful interpretation. Antioxidants are integral in tackling male infertility attributed to oxidative stress. The current findings underscore their therapeutic value, yet there’s a pressing need for deeper, comprehensive research. Future studies should focus on refining dosage guidelines, identifying potential side effects, and discerning the most efficacious antioxidant combinations for male infertility solutions.

14 February 2023 in Genes
Verified
Journal Article
Open access
PDF file
Aris KaltsasAris Kaltsas
Aris Kaltsas
EMEfthalia Moustakli
Efthalia Moustakli
Konstantinos ATHANASIOS ZIKOPOULOSKonstantinos ATHANASIOS ZIKOPOULOS
Konstantinos ATHANASIOS ZIKOPOULOS
Ioannis GeorgiouIoannis Georgiou
Ioannis Georgiou
Fotios DimitriadisFotios Dimitriadis
Fotios Dimitriadis
ATHANASIOS ZACHARIOUATHANASIOS ZACHARIOU
ATHANASIOS ZACHARIOU
The average age of fathers at first pregnancy has risen significantly over the last decade owing to various variables, including a longer life expectancy, more access to contraception, later marriage, and other factors. As has been proven in several studies, women over 35 years of age have an increased risk of infertility, pregnancy problems, spontaneous abortion, congenital malformations, and postnatal issues. There are varying opinions on whether a father’s age affects the quality of his sperm or his ability to father a child. First, there is no single accepted definition of old age in a father. Second, much research has reported contradictory findings in the literature, particularly concerning the most frequently examined criteria. Increasing evidence suggests that the father’s age contributes to his offspring’s higher vulnerability to inheritable diseases. Our comprehensive literature evaluation shows a direct correlation between paternal age and decreased sperm quality and testicular function. Genetic abnormalities, such as DNA mutations and chromosomal aneuploidies, and epigenetic modifications, such as the silencing of essential genes, have all been linked to the father’s advancing years. Paternal age has been shown to affect reproductive and fertility outcomes, such as the success rate of in vitro fertilisation (IVF), intracytoplasmic sperm injection (ICSI), and premature birth rate. Several diseases, including autism, schizophrenia, bipolar disorders, and paediatric leukaemia, have been linked to the father’s advanced years. Therefore, informing infertile couples of the alarming correlations between older fathers and a rise in their offspring’s diseases is crucial, so that they can be effectively guided through their reproductive years.

Verified
Journal Article
Open access
PDF file
Aris KaltsasAris Kaltsas
Aris Kaltsas
AZAthanasios Zikopoulos
Athanasios Zikopoulos
Fotios DimitriadisFotios Dimitriadis
Fotios Dimitriadis
DSDanja Sheshi
Danja Sheshi
MPMagdalena Politis
Magdalena Politis
ATHANASIOS ZACHARIOUATHANASIOS ZACHARIOU
ATHANASIOS ZACHARIOU
Erectile dysfunction (ED) is a prevalent condition affecting men’s sexual health, with oxidative stress (OS) having recently been identified as a significant contributing causative factor. This narrative review aims to elucidate the role of OS in the pathophysiology of ED, focusing on impact, mechanisms, and potential therapeutic interventions. Key findings indicate that OS disrupts endothelial function and nitric oxide (NO) signaling, crucial for erectile function. Various sources of reactive oxygen species (ROS) and their detrimental effects on penile tissue are discussed, including aging, diabetes mellitus, hypertension, hyperlipidemia, smoking, obesity, alcohol consumption, psychological stress, hyperhomocysteinemia, chronic kidney disease, and sickle cell disease. Major sources of ROS, such as NADPH oxidase, xanthine oxidase, uncoupled endothelial NO synthase (eNOS), and mitochondrial electron transport, are identified. NO is scavenged by these ROS, leading to endothelial dysfunction characterized by reduced NO availability, impaired vasodilation, increased vascular tone, and inflammation. This ultimately results in ED due to decreased blood flow to penile tissue and the inability to achieve or maintain an erection. Furthermore, ROS impact the transmission of nitrergic neurotransmitters by causing the death of nitrergic neurons and reducing the signaling of neuronal NO synthase (nNOS), exacerbating ED. Therapeutic approaches targeting OS, including antioxidants and lifestyle modifications, show promise in ameliorating ED symptoms. The review underscores the need for further research to develop effective treatments, emphasizing the interplay between OS and vascular health in ED. Integrating pharmacological and non-pharmacological strategies could enhance clinical outcomes for ED patients, advocating for OS management in ED treatment protocols to improve patient quality of life.

26 July 2023 in Antioxidants
Verified
Journal Article
Open access
PDF file
Aris KaltsasAris Kaltsas
Aris Kaltsas
AZAthanasios Zikopoulos
Athanasios Zikopoulos
EMEfthalia Moustakli
Efthalia Moustakli
ATHANASIOS ZACHARIOUATHANASIOS ZACHARIOU
ATHANASIOS ZACHARIOU
GTGeorgia Tsirka
Georgia Tsirka
Fotios DimitriadisFotios Dimitriadis
Fotios Dimitriadis
Oxidative stress (OS), which arises through an imbalance between the formation of reactive oxygen species (ROS) and antioxidant defenses, plays a key role in the pathophysiology of female infertility, with the latter constituting just one of a number of diseases linked to OS as a potential cause. The aim of the present article is to review the literature regarding the association between OS and female infertility. Among the reproductive diseases considered are endometriosis and polycystic ovary syndrome (PCOS), while environmental pollutants, lifestyle variables, and underlying medical conditions possibly resulting in OS are additionally examined. Current evidence points to OS likely contributing to the pathophysiology of the above reproductive disorders, with the amount of damage done by OS being influenced by such variables as duration and severity of exposure and the individual’s age and genetic predisposition. Also discussed are the processes via which OS may affect female fertility, these including DNA damage and mitochondrial dysfunction. Finally, the last section of the manuscript contains an evaluation of treatment options, including antioxidants and lifestyle modification, capable of minimizing OS in infertile women. The prime message underlined by this review is the importance of considering OS in the diagnosis and treatment of female infertility. Further studies are, nevertheless required to identify the best treatment regimen and its ideal duration.

17 January 2025 in Genes
Verified
Journal Article
Open access
PDF file
Aris KaltsasAris Kaltsas
Aris Kaltsas
EMEleftheria Markou
Eleftheria Markou
MKMaria-Anna Kyrgiafini
Maria-Anna Kyrgiafini
AZAthanasios Zikopoulos
Athanasios Zikopoulos
Evangelos N. SymeonidisEvangelos N. Symeonidis
Evangelos N. Symeonidis
MCMichael Chrisofos
Michael Chrisofos
Male reproductive health is governed by an intricate interplay of genetic, epigenetic, and environmental factors. Epigenetic mechanisms—encompassing DNA methylation, histone modifications, and non-coding RNA activity—are crucial both for spermatogenesis and sperm maturation. However, oxidative stress, driven by excessive reactive oxygen species, disrupts these processes, leading to impaired sperm function and male infertility. This disruption extends to epigenetic modifications, resulting in abnormal gene expression and chromatin remodeling that compromise genomic integrity and fertilization potential. Importantly, oxidative-stress-induced epigenetic alterations can be inherited, affecting the health and fertility of offspring and future generations. This review investigates how oxidative stress influences epigenetic regulation in male reproduction by modifying DNA methylation, histone modifications, and non-coding RNAs, ultimately compromising spermatogenesis. Additionally, it discusses the transgenerational implications of these epigenetic disruptions and their potential role in hereditary infertility and disease predisposition. Understanding these mechanisms is vital for developing therapeutic strategies that mitigate oxidative damage and restore epigenetic homeostasis in the male germline. By integrating insights from molecular, clinical, and transgenerational research, this work emphasizes the need for targeted interventions to enhance male reproductive health and prevent adverse outcomes in progeny. Furthermore, elucidating the dose–response relationships between oxidative stress and epigenetic changes remains a critical research priority, informing personalized diagnostics and therapeutic interventions. In this context, future studies should adopt standardized markers of oxidative damage, robust clinical trials, and multi-omic approaches to capture the complexity of epigenetic regulation in spermatogenesis. Such rigorous investigations will ultimately reduce the risk of transgenerational disorders and optimize reproductive health outcomes.

11 February 2025 in Diseases
Verified
Journal Article
Open access
PDF file
Aris KaltsasAris Kaltsas
Aris Kaltsas
TGTIMOLEON GIANNAKAS
TIMOLEON GIANNAKAS
MSMarios Stavropoulos
Marios Stavropoulos
ZKZisis Kratiras
Zisis Kratiras
MCMichael Chrisofos
Michael Chrisofos
Background/Objectives: Benign prostatic hyperplasia (BPH) is among the most common conditions affecting men as they age, resulting in lower urinary tract symptoms (LUTS) that can profoundly impact quality of life. While historically attributed primarily to androgenic imbalances, current evidence implicates additional factors—particularly oxidative stress (OS) and chronic inflammation—in BPH pathogenesis. This review aims to synthesize research on the interplay between OS, inflammation, and hormonal regulation in BPH, emphasizing their clinical relevance and potential therapeutic implications. Methods: A comprehensive review of peer-reviewed literature was conducted focusing on mechanistic studies, clinical trials, and observational reports. Searches included data on ROS generation, antioxidant capacity, inflammatory mediators, and their contribution to pathological prostatic overgrowth. Potential interventions targeting OS—such as antioxidant supplementation, anti-inflammatory drugs, vitamin D receptor agonists, and phytotherapeutics—were also evaluated for their efficacy and safety profiles. Results: Chronic inflammation and OS were consistently identified within hyperplastic prostate tissue. Excessive ROS production, diminished antioxidant defense, and sustained cytokine release create a proproliferative and antiapoptotic environment, accelerating disease progression. Metabolic comorbidities (e.g., obesity, insulin resistance) further exacerbate these imbalances. Standard therapies (α-blockers and 5-ARIs) effectively relieve symptoms but do not directly address the oxidative–inflammatory axis. Emerging evidence suggests that pharmacological and dietary approaches targeting OS and inflammation may reduce prostate volume expansion and alleviate LUTS. Conclusions: Findings indicate that OS and inflammation are key contributors to BPH progression. Incorporating antioxidant and anti-inflammatory strategies alongside conventional treatments holds promise for improving clinical outcomes and patient quality of life. Future research should focus on validating OS-specific biomarkers and optimizing personalized therapy regimens.