Andre Kamkin

Prof. Dr. Andre Kamkin


Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

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

Representative Publications

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20 November 2023 in Cancers
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Journal Article
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ISIliyana Sazdova
Iliyana Sazdova
Milena Keremidarska-MarkovaMilena Keremidarska-Markova
Milena Keremidarska-Markova
DDDaniela Zdravkova Dimitrova
Daniela Zdravkova Dimitrova
VMVadim Mitrokhin
Vadim Mitrokhin
AKAndre Kamkin
Andre Kamkin
MMMitko Mladenov
Mitko Mladenov
EF24, a synthetic monocarbonyl analog of curcumin, shows significant potential as an anticancer agent with both chemopreventive and chemotherapeutic properties. It exhibits rapid absorption, extensive tissue distribution, and efficient metabolism, ensuring optimal bioavailability and sustained exposure of the target tissues. The ability of EF24 to penetrate biological barriers and accumulate at tumor sites makes it advantageous for effective cancer treatment. Studies have demonstrated EF24’s remarkable efficacy against various cancers, including breast, lung, prostate, colon, and pancreatic cancer. The unique mechanism of action of EF24 involves modulation of the nuclear factor-kappa B (NF-κB) and nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways, disrupting cancer-promoting inflammation and oxidative stress. EF24 inhibits tumor growth by inducing cell cycle arrest and apoptosis, mainly through inhibiting the NF-κB pathway and by regulating key genes by modulating microRNA (miRNA) expression or the proteasomal pathway. In summary, EF24 is a promising anticancer compound with a unique mechanism of action that makes it effective against various cancers. Its ability to enhance the effects of conventional therapies, coupled with improvements in drug delivery systems, could make it a valuable asset in cancer treatment. However, addressing its solubility and stability challenges will be crucial for its successful clinical application.

10 June 2024 in Cells
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Journal Article
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VMVadim Mitrokhin
Vadim Mitrokhin
NHNikola Hadzi-Petrushev
Nikola Hadzi-Petrushev
VKViktor Kazanski
Viktor Kazanski
SSStanislav Schileyko
Stanislav Schileyko
OKOlga Kamkina
Olga Kamkina
MMMitko Mladenov
Mitko Mladenov
This manuscript explores the intricate role of acetylcholine-activated inward rectifier potassium (KACh) channels in the pathogenesis of atrial fibrillation (AF), a common cardiac arrhythmia. It delves into the molecular and cellular mechanisms that underpin AF, emphasizing the vital function of KACh channels in modulating the atrial action potential and facilitating arrhythmogenic conditions. This study underscores the dual nature of KACh activation and its genetic regulation, revealing that specific variations in potassium channel genes, such as Kir3.4 and K2P3.1, significantly influence the electrophysiological remodeling associated with AF. Furthermore, this manuscript identifies the crucial role of the KACh-mediated current, IKACh, in sustaining arrhythmia through facilitating shorter re-entry circuits and stabilizing the re-entrant circuits, particularly in response to vagal nerve stimulation. Experimental findings from animal models, which could not induce AF in the absence of muscarinic activation, highlight the dependency of AF induction on KACh channel activity. This is complemented by discussions on therapeutic interventions, where KACh channel blockers have shown promise in AF management. Additionally, this study discusses the broader implications of KACh channel behavior, including its ubiquitous presence across different cardiac regions and species, contributing to a comprehensive understanding of AF dynamics. The implications of these findings are profound, suggesting that targeting KACh channels might offer new therapeutic avenues for AF treatment, particularly in cases resistant to conventional approaches. By integrating genetic, cellular, and pharmacological perspectives, this manuscript offers a holistic view of the potential mechanisms and therapeutic targets in AF, making a significant contribution to the field of cardiac arrhythmia research.

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Journal Article
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VMVadim Mitrokhin
Vadim Mitrokhin
AKAndre Kamkin
Andre Kamkin
IBIrina Babkina
Irina Babkina
ISIrina Savinkova
Irina Savinkova
SSStanislav Schileyko
Stanislav Schileyko
MMMitko Mladenov
Mitko Mladenov
The heart–brain axis is a bidirectional communication network composed of neural, humoral, and immune pathways that sustain cardiovascular and brain homeostasis. There is mounting evidence that viral myocarditis—a prototype of inflammatory heart disease—acts beyond the myocardium, triggering systemic immune cascades that lead to central nervous system (CNS) involvement. This involvement creates an inflammatory continuum in which cardiac damage and neuroinflammation reinforce each other via common cytokine and molecular mediators. Central mediators in this axis are the proinflammatory cytokines IL-1β, IL-6, tumor necrosis factor (TNF)-α, IL-17, IL-23, and IL-33. These cytokines are released by infected cardiomyocytes and immune cells during myocarditis, inducing endothelial cell (EC) activation, and causing blood–brain barrier (BBB) disruption. Simultaneously, TLR/NF-κB signaling and the stability of endothelial junctions are modulated by regulatory microRNAs such as miR-155 and miR-146a/b, which respectively enhance or attenuate inflammatory signals. Disruption of the BBB allows cytokines and immune cells to enter the brain parenchyma, where they activate microglia and astrocytes through NF-κB-dependent pathways. The resultant neuroinflammation disrupts autonomic equilibrium and leads to sympathetic overdrive, arrhythmogenesis, and overall worsening of cardiac injury, thus forming a self-perpetuating inflammatory cycle between the heart and the brain. Selective modulation of cytokines (anti-IL-1β, IL-6 receptor antagonists, and TNF-α modulators), blockade of the NLRP3 inflammasome, and miRNA therapy (anti-miR-155 and miR-146a mimics) are potential approaches for interrupting the heart–brain inflammatory circuit. In addition, neurotrophic therapies preserving BBB integrity may reduce secondary neuronal damage. Therefore, a future precision cardio-neuroprotective paradigm will rely on the integration of anti-inflammatory, molecular, and neurovascular strategies aimed at limiting systemic cytokine propagation and restoring bidirectional homeostasis through the heart–brain axis.

Verified
Journal Article
Open access
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OKOlga V. Kamkina
Olga V. Kamkina
ARAnastasia S. Rodina
Anastasia S. Rodina
AKAndre Kamkin
Andre Kamkin
ABAndrey Bilichenko
Andrey Bilichenko
VKViktor E. Kazansky
Viktor E. Kazansky
MMMitko Mladenov
Mitko Mladenov
L-type Ca2+ channels, particularly CaV1.2, play a crucial role in cardiac excitation-contraction coupling and are known to exhibit mechanosensitivity. However, the mechanisms regulating their response to mechanical stress remain poorly understood. To investigate the mechanosensitivity and nitric oxide (NO)-dependent regulation of L-type Ca2+ channels in rat ventricular cardiomyocytes, we used RNA sequencing to assess isoform expression and whole-cell patch-clamp recordings to measure L-type Ca2+ current (ICa,L) under controlled mechanical and pharmacological conditions. RNA sequencing revealed predominant expression of CaV1.2 (TPM: 0.1170 ± 0.0075) compared to CaV1.3 (0.0021 ± 0.0002) and CaV1.1 (0.0002 ± 0.0002). Local axial stretch (6–10 μm) consistently reduced ICa,L in proportion to stretch magnitude. The NO donor SNAP (200 μM) had variable effects on basal ICa,L in unstretched cells (stimulatory, inhibitory, or biphasic) but consistently restored stretch-reduced ICa,L to control levels. Ascorbic acid (10 μM), which reduces S-nitrosylation, increased basal ICa,L and partially restored the reduction caused by stretch, implicating S-nitrosylation in channel regulation. The sGC inhibitor ODQ (5 μM) decreased ICa,L in both stretched and unstretched cells, indicating involvement of the NO–cGMP pathway. Mechanical stress modulates L-type Ca2+ channels through a complex interplay between S-nitrosylation and NO–cGMP signaling, with S-nitrosylation playing a predominant role in stretch-induced effects. This mechanism may represent a key component of cardiac mechanotransduction and could be relevant for therapeutic targeting in cardiac pathologies involving mechanically induced dysfunction.

Verified
Journal Article
Open access
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ABAndrey Bilichenko
Andrey Bilichenko
AZAlexandra D. Zolotareva
Alexandra D. Zolotareva
OKOlga V. Kamkina
Olga V. Kamkina
VZValentin Zolotarev
Valentin Zolotarev
ARAnastasia S. Rodina
Anastasia S. Rodina
AKAndre Kamkin
Andre Kamkin
Cardiomyocytes, similarly to cells in various tissues, are responsive to mechanical stress of all types, which is reflected in the significant alterations to their electrophysiological characteristics. This phenomenon, known as mechanoelectric feedback, is based on the work of mechanically gated channels (MGCs) and mechano-sensitive channels (MSCs). Since microgravity (MG) in space, as well as simulated microgravity (SMG), changes the morphological and physiological properties of the heart, it was assumed that this result would be associated with a change in the expression of genes encoding MGCs and MSCs, leading to a change in the synthesis of channel proteins and, ultimately, a change in channel currents during cell stretching. In isolated ventricular cardiomyocytes of rats exposed to SMG for 14 days, the amount of MGCs and MSCs gene transcripts was studied using the RNA sequencing method by normalizing the amount of “raw” reads using the Transcripts Per Kilobase Million (TPM) method. Changes in the level of channel protein, using the example of the MGCs TRPM7, were assessed by the Western blot method, and changes in membrane ion currents in the control and during cardiomyocyte stretching were assessed by the patch-clamp method in the whole-cell configuration. The data obtained demonstrate that SMG results in a multidirectional change in the expression of genes encoding various MGCs and MSCs. At the same time, a decrease in the TPM of the MGCs TRPM7 gene leads to a decrease in the amount of TRPM7 protein. The resulting redistribution in the synthesis of most channel proteins leads to a marked decrease in the sensitivity of the current through MGCs to cell stretching and, ultimately, to a change in the functioning of the heart.

Verified
Journal Article
Open access
PDF file
AKAndre Kamkin
Andre Kamkin
VZValentin Zolotarev
Valentin Zolotarev
OKOlga Kamkina
Olga Kamkina
VMVadim Mitrokhin
Vadim Mitrokhin
VKViktor E. Kazansky
Viktor E. Kazansky
MMMitko Mladenov
Mitko Mladenov
Although hypergravity may influence cardiac mechanosensitivity, the effects on specific ion channels remain inadequately understood. This research examined the effects of long-term hypergravity on the functional activity and transcriptional expression of mechanosensitive channels (MSCs) in rat ventricular cardiomyocytes. After 14 days of exposure to 4g, rats were subjected to molecular and electrophysiological analyses. Significant remodeling of MSC-encoding genes was revealed by RNA-seq. Trpm7 (+41.23%, p = 0.0073) and Trpc1 (+68.23%, p = 0.0026) were significantly upregulated among non-selective cation channels, while Trpv2 (−62.19%, p = 0.0044) and Piezo2 (−57.58%, p = 0.0079) were significantly downregulated. Kcnmb1 (−47.84%, p = 0.0203) was suppressed, whereas Traak/K2P4.1 showed a strong increase (+239.48%, p = 0.0092), among K+-selective MSCs. Furthermore, Kir6.1 was significantly downregulated (−75.8%, p = 0.0085), whereas Kir6.2 was significantly upregulated (+38.58%, p = 0.0317). These results suggest targeted transcriptional reprogramming that suppresses pathways associated with maladaptive Ca2+ influx while enhancing Ca2+-permeable mechanosensitive channels alongside stabilized K+ conductance. At the structural level, cardiomyocytes from hypergravity exposure showed a 44% increase in membrane capacitance, consistent with hypertrophic remodeling, and sarcomere elongation (p < 0.001). Functionally, stretch-activated current (ISAC) was markedly hypersensitive in patch-clamp analysis: currents were induced at very small displacements (1–2 µm) and were significantly larger under 4–10 µm stretch (222–107% of control values). These findings indicate that chronic hypergravity induces coordinated molecular, structural, and functional remodeling of cardiomyocytes, characterized by increased membrane excitability, compensatory stabilizing mechanisms, and enhanced Ca2+ signaling. This demonstrates the flexibility of cardiac mechanotransduction under prolonged gravitational stress, with potential implications for understanding cardiovascular risks, arrhythmias, and hypertrophy associated with altered gravity environments.