GENERAL PHYSIOLOGY AND BIOPHYSICS

Pulmonary alveolar proteinosis: Clinical and morphological overview of a rare disease associated with macrophage dysfunction
Javorská B, Slivka R, Durcová B, Vrbenská A, Škarda J, Vecanová J, Hvizdošová N, Makovická M, Kamarád V and Muri J
Pulmonary alveolar proteinosis (PAP) is a rare disease characterised by excessive accumulation of surfactant components in alveolar macrophages, alveoli, and peripheral airways. The accumulation of surfactant is associated with only a minimal inflammatory response but can lead to the development of pulmonary fibrosis. Three clinical forms of PAP are distinguished - primary, secondary and congenital. In recent years, significant findings have helped to clarify the ethiology and pathogenesis of the disease. Apart from impaired surfactant protein function, a key role in the development of PAP is played by signal pathway of granulocyte and macrophage colonies stimulating growth factor (GM-CSF) which is necessary for the functioning of alveolar macrophages and for surfactant homeostasis. Surfactant is partially degraded by alveolar macrophages that are stimulated by GM-CSF. The role of GM-CSF has been shown especially in primary PAP, which is currently considered an autoimmune disease involving the development of GM-CSF neutralising autoantibodies. Clinically, the disease may be silent or manifest with dyspnoeic symptoms triggered by exertion and cough. However, there is a 10 to 15% rate of patients who develop respiratory failure. Total pulmonary lavage is regarded as the standard method of treatment. In addition, recombinant human GM-CSF has been studied as a prospective therapy for the treatment of PAP.
Basic pharmacological evaluation of modified phenyl carbamic acid derivatives on cardiovascular functions under in vitro conditions in rats
Kralova E and Malik I
The study aimed to evaluate the basic pharmacological effects of modified phenyl carbamic acid derivates with a basic part made of N-phenylpiperazine (compounds 6a, 6b, 6c, 6d) in Wistar rats. The compounds were evaluated for their ability to decrease the phenylephrine-induced contraction of the aortic strips of rats after repeated administration of the compounds and their ability to inhibit the positive chronotropic effect of isoproterenol on spontaneously beating rat atria. The ability to inhibit the vasoconstriction effect of phenylephrine was confirmed in all compounds in the range from 10.39 % to 13.65 %. The most significant vasoconstriction was achieved in compound 6d (86.35%, p < 0.001). None of the compounds reached the effect of carvedilol. All compounds proved an antagonistic ability to the positive chronotropic effect of isoproterenol. The highest value of the anti-isoproterenol effect was identified for the compound 6c (pA2 = 8.21 ± 0.56; p < 0.05). Only compound 6a decreased heart rate significantly (by 3.17%, p < 0.05), so we can indicate its potential negative chronotropic effect. The obtained results showed that the evaluated compounds confirmed the basic characteristics of beta-blockers with additional α-adrenolytic properties.
Small nucleolar RNA 42 facilitates the progression of hepatocellular carcinoma through PI3K/Akt signaling pathway
Liu J, Deng J, Liang Q, Yu Y, Yang X and Sun G
Small nucleolar RNAs may serve as new potential biomarkers for the diagnosis and treatment of liver cancer. The purpose of our study was to reveal the mechanism small nucleolar RNA 42 (SNORA42) affects the proliferation and migration of liver cancer cells. Quantitative real-time PCR (qRT-PCR) was performed to detect the expression of SNORA42 and its host gene. Cell proliferation and migration were measured using the CCK-8 and Transwell assays, respectively. Western blotting was performed to measure the expression of the proteins affected by SNORA42. SNORA42 overexpression could reinforce the proliferation of hepatocellular carcinoma (HCC) cells, and promote the migration of hepatocellular carcinoma cells. In addition, SNORA42 did not affect the expression of host genes KIAA0907. SNORA42 is one of the most important components of the PI3K/Akt signaling pathway. SNORA42 augmented phospho-Akt expression, which was reversed by PI3K and Akt inhibitors. Our study displayed that SNORA42 may affect the proliferation and migration of HCC cells by interfering with the PI3K/Akt signaling pathway. Thus, SNORA42 may be a new target for detecting or treating HCC.
Silencing Map3k7 suppresses pyroptosis to alleviate bronchopulmonary dysplasia through inhibiting the TGF-β1/Smad3 pathway
Zhen H, Wei Q, Wei B, Huang Q and Li R
Bronchopulmonary dysplasia (BPD) is a serious complication in premature infants. This study aimed to investigate the mechanism of mitogen-activated protein 3 kinase 7 (Map3k7) affecting BPD by regulating caspase-1 mediated pyroptosis. The morphology of the lung tissue was observed using hematoxylin-eosin staining. TUNEL staining was performed to detect tissue apoptosis. RNA-seq and protein-protein interaction (PPI) network were performed to identify hub genes. Cell viability and apoptosis was analyzed using the CCK-8 assay and flow cytometry, respectively. Pyroptosis-related factors, inflammatory factors, oxidative stress indicators, and pathway-related proteins were detected using ELISA, qRT-PCR, and Western blotting. Hyperoxia-induced neonatal rats showed alveolar simplification with increased alveolar lumen, and decreased density of secondary alveolar cristae, demonstrating the successful BPD model. Map3k7 was identified as the crucial gene that was upregulated in BPD. Silencing Map3k7 promoted cell proliferation and suppressed apoptosis, inflammation, oxidative stress, and pyroptosis in hyperoxia-induced AEC-II, and alleviated BPD progression in hyperoxia-induced rats. Furthermore, silencing Map3k7 inhibited the TGF-β1/Smad3 pathway, and SRI-011381, the TGF-β pathway activator, weakened the inhibitory effects of silencing Map3k7 on hyperoxia-induced AEC-II. Silencing Map3k7 suppressed pyroptosis to alleviate BPD through inhibiting the TGF-β1/Smad3 pathway, providing a direction for the treatment of BPD in premature infants.
Senescence in neural cell lines: comparative insights from SH-SY5Y and ReNcell VM
Macova K, Mjartinova D, Fialova L, Nakladal D and Fricova D
Senescence, a crucial yet paradoxical phenomenon in cellular biology, acts as a barrier against cancer progression while simultaneously promoting aging and age-related pathologies. This duality underlines the importance of precise monitoring of senescence response, especially with regard to the proposed use of drugs selectively removing senescent cells. In particular, little is known about the role of senescence in neurons and in neurodegenerative diseases. Our study investigates the senescence response in neuroblastoma SH-SY5Y cells and human neural progenitor ReNcell VM cells exposed to doxorubicin, a chemotherapeutic agent known to induce DNA damage and subsequent senescence. Through a comprehensive analysis employing the most robust senescence markers, we characterized the senescence-associated patterns in these neural cell lines including cellular morphological changes, SA-beta-gal, γH2A.X, p21Waf1/Cip1 and p16Ink4a. Our findings indicate that ReNcell VM cells exhibit greater senescence-associated response at lower doxorubicin concentrations compared to SH-SY5Y cells. Additionally, we observed cell-type-specific differences in timing and levels of the expression of key cell cycle regulators during senescence. Our results emphasize the necessity of cell-type-specific strategies in senescence research with regard to implications as well as limitations for translation into aging and neurodegenerative disorders.
Senkyunolide A attenuates cerebral ischemia-reperfusion injury by inhibiting NLRP3-mediated ferroptosis in PC12 cells
Zhang Q, Wang Y, Xiu Y, Zhang Z, Zou T, Wu H and Quan Y
Cerebral ischemia-reperfusion (I/R) is a serious complication in patients with ischemic stroke. Senkyunolide A (SenA) can alleviate neuronal cell damage induced by cerebral I/R; however, the exact action mechanism remains unclear. An in vitro cellular injury model was established by inducing PC-12 cells with OGD/R. The viability of SenA-treated PC-12 cells with or without OGD/R induction was detected with CCK-8 assay while the cell apoptosis was detected using TUNEL. The secretion of inflammatory cytokines, the activity of ROS, mitochondrial membrane potential and mtROS level were measured with ELISA, ROS assay kits, JC-1 staining and MitoSOX Red assay, respectively. The level of Fe2+ was detected with Fe2+ assay kits and lipid peroxidation was detected with TBARS assay. The expressions of lipid peroxides were measured using corresponding assay kits. Western blot was used to measure the expressions of NLRP3, apoptosis-, and ferroptosis-related proteins. The transfection efficiency of OV-NLRP3 was also detected using Western blot. The present study showed that SenA could attenuate viability damage, inflammatory response, oxidative stress, apoptosis and ferroptosis in OGD/R-induced PC-12 cells and it was identified that the cytoprotective effects of SenA on PC-12 cells stimulated by OGD/R may be associated with the inhibition of NLPR3. Collectively, SenA protects neuronal cells against cerebral I/R injury through the inhibition of NLRP3-mediated ferroptosis.
TFDP1 overexpression promotes apoptosis of nucleus pulposus cells in intervertebral disc degeneration through regulating ADAM15/MMP9 axis
Tong X, Xiao L and Xin Y
Intervertebral disc degeneration (IVDD) is a common contributor for low back pain, which is featured by loss of extracellular matrix and nucleus pulposus cells (NPCs). Hence, our current study is undertaken to explore the potential mechanism of NPC apoptosis during IVDD. Transcription factor Dp-1 (TFDP1) expression in degenerative and non-degenerative intervertebral disc tissues was analyzed by bioinformatics. After transfection as needed, viability and apoptosis of NPCs were evaluated by cell counting kit-8 assay and flow cytometry, respectively. Western blot or quantitative real-time reverse transcription polymerase chain reaction was applied to assess expressions of TFDP1, matrix metallopeptidase 9 (MMP9), a disintegrin and metalloproteinase 15 (ADAM15), and apoptosis-associated proteins. TFDP1 expression was upregulated in degenerative intervertebral disc tissues. TFDP1 overexpression repressed viability, promoted apoptosis, increased expressions of Bax, Cleaved caspase 3, MMP9 and ADAM15, and decreased Bcl-2 expression in NPCs, while TFDP1 silencing did conversely. ADAM15 silencing promoted viability, inhibited apoptosis, increased Bcl-2 expression, and decreased Bax, Cleaved caspase 3, and MMP9 expressions in NPCs, which were reversed by TFDP1 overexpression. TFDP1 overexpression promotes apoptosis of NPCs in IVDD through regulating ADAM15/MMP9 axis, highlighting its role as a molecular target for the treatment of low back pain.
Transcription factor Yy1 modulates Trem1 to control LPS-triggered neuroinflammation and oxidative stress in mouse astrocytes via the NF-κB pathway
Ke W, Ye Z, Huang Y and Ye S
Dysfunction of astrocytes has a crucial role in the pathology of depression. Here, we aimed to define the exact action of the ubiquitous transcription factor (TF) Yin Yang-1 (Yy1) in depression pathogenesis and astrocytic dysfunction. A chronic unpredictable mild stress (CUMS) mouse model was generated. Primary mouse astrocytes were exposed to lipopolysaccharide (LPS). Cell growth was determined by CCK-8 and EdU assays. The direct interaction of Yy1 and the Trem1 promoter was validated by chromatin immunoprecipitation (ChIP) and luciferase assays. In CUMS mice, the levels of Yy1 and inflammatory cytokines were augmented and oxidative stress was enhanced. Functionally, disruption of Yy1 or triggering receptor expressed on myeloid cell 1 (Trem1) relieved LPS-triggered pro-growth, pro-inflammation, and pro-oxidative stress effects in mouse astrocytes. Mechanistically, Yy1 directly promoted the transcription and expression of Trem1 by binding to the Trem1 promoter. Yy1 disruption exerted regulatory impacts in LPS-induced mouse astrocytes via down-regulation of Trem1. Additionally, the Yy1/Trem1 cascade could modulate the activation of the NF-κB signaling in mouse astrocytes. Our study defines that Yy1 disruption relieves LPS-triggered neuroinflammation and oxidative stress in mouse astrocytes via the NF-κB pathway by down-regulating Trem1, providing possible strategies for depression treatment.
Sevoflurane regulates DICER1 expression by targeting miR-192-5p to protect cerebral ischemia-reperfusion injury in rats
Yuan B, Zhao Q, Xiao WQ, Ouyang JJ, Huang J and Fan YH
Sevoflurane is considered an effective neuroprotector in cerebral ischemia/reperfusion injury (CIRI). Sevoflurane preconditioning in CIRI, however, remains unknown precisely by its molecular mechanism. The middle cerebral artery occlusion reperfusion (MCAO/R) rat model was established, and neurological function was evaluated by Zea-Longa score. Cerebral water content was determined to assess cerebral edema. Brain pathological condition was observed by hematoxylin and eosin staining, the intact changes of rat neurons were observed by Nissl staining, and neuronal apoptosis was measured by TUNEL staining. In addition, miR-192-5p and DICER1 levels were detected by RT-qPCR or Western blot, and the targeting relationship between miR-192-5p and DICER1 was verified by bioinformatics analysis and luciferase reporting experiment. miR-192-5p was up-regulated and DICER1 was down-regulated in MCAO/R rats. Sevoflurane preconditioning could decrease miR-192-5p and promote DICER1 expression. Sevoflurane preconditioning could alleviate brain tissue injury and neuronal apoptosis in MCAO/R rats. DICER1 expression was negatively regulated by targeting miR-192-5p. Elevating miR-192-5p or suppressing DICER1 rescued the protective effect of sevoflurane preconditioning on MCAO/R rats. Sevoflurane alleviates brain injury in MCAO/R rats via miR-192-5p/DICER1 axis.
TGF-β1 inhibits apoptosis of cardiomyocytes H9c2 by regulating autophagy and ERK pathway
Liu Y, Lin S, Wang J, Jiang J, Shu A and Zhou M
This study aimed to explore the expression and mechanism of transforming growth factor β1 (TGF-β1) in oxygen glucose deprivation reperfusion (OGD/R)-induced ischemia/reperfusion (I/R) injury. An OGD/R model was established in cardiomyocytes H9c2, resulting in upregulation of Beclin-1 and LC3II/LC3I expression. Upon overexpression of TGF-β1, the viability of OGD/R-induced H9c2 cells was enhanced, while apoptosis was suppressed by downregulating Bax and upregulating Bcl-2. Additionally, TGF-β1 overexpression promoted autophagy in OGD/R-induced H9c2 cells by further upregulating the levels of Beclin-1 and LC3II/LC3I. Importantly, treatments with 3-methyladenine (3-MA), an autophagy inhibitor, and U0126, an extracellular signal-related kinases 1 and 2 (ERK1/2) inhibitor, significantly inhibited cell viability, increased intracellular reactive oxygen species levels, promoted cell apoptosis (by upregulating Bax and downregulating Bcl-2), and inhibited cell autophagy (by downregulating Beclin-1 and LC3II/LC3I) in OGD/R-induced H9c2 cells with TGF-β1 overexpression. Additionally, OGD/R induction significantly increased the levels of p-ERK, p-P38, and p-JNK, which were further enhanced by TGF-β1 overexpression. U0126 treatments significantly downregulated the p-ERK compared to OGD/R-induced H9c2 cells with TGF-β1 overexpression. Our study suggests that TGF-β1 could inhibit the growth of cardiomyocytes H9c2 by regulating autophagy and ERK pathways, providing a new theoretical basis for the treatment and prevention of OGD/R in clinical practice.
Neuroprotective effects of coffee-derived exosome-like nanoparticles against Aβ-induced neurotoxicity
Esmekaya MA and Ertekin B
The present study aimed to provide experimental evidence that CDELNs (coffee-derived exosome-like nanoparticles) may be a candidate for the treatment or prevention of amyloid-β (Aβ)-induced Alzheimer's disease (AD). An in vitro Alzheimer's model was created with Aβ-induced toxicity in mouse hippocampal neuronal cells (HT-22). Aβ(1-42)-exposed cells were treated with different concentrations of CDELNs (1-50 μg/ml) and the viability of cells was analyzed. The change in the mitochondrial membrane potential (ΔΨm) of cells was also determined. CDELNs treatment increased the viability of Aβ(1-42 )-toxicity-induced HT-22 cells significantly. The increase in the viability of Aβ(1-42)-toxicity-induced cells was correlated with an improvement in ΔΨm. CDELNs treatment restored the dissipated ΔΨm. These results suggested that CDELNs protect neuronal cells against Aβ(1-42)-induced neurotoxicity by repairing mitochondrial dysfunction. CDELNs might be a useful neuroprotective agent for the treatment or prevention of Aβ-induced AD. Further animal and clinical studies should be carried out to investigate the neuroprotective potential of CDELNs against Aβ-induced AD.
HMGB1 impacts the intestinal epithelial barrier by initiating NETs to regulate macrophage polarization
Chen X, Wu J, Liu M, Han Z, Tan J, Zhu Q, Huang X and Tian X
High mobility group box 1 (HMGB1) has the capability of activating the immune response and taking part in macrophage polarization. Despite this, there is significant scope for exploration into how HMGB1 regulates macrophage polarization phenotype and influences intestinal epithelial barrier function. Investigating the role of HMGB1 in the creation of neutrophil extracellular traps (NETs) and the mechanism of its impact on macrophages could provide novel insights into intervening in intestinal inflammation and barrier damage. Therefore, the research examined the relationship between the macrophage polarization phenotype and HMGB1. Additionally, we analyzed how cell proliferation and cytokines changed in CaCo-2 cells following co-culture with HMGB1-influenced macrophages and intestinal epithelial CaCo-2 cells. We discovered that up-regulation of HMGB1 expression enhanced the creation of NETs, whereas inhibition of NETs formation led macrophages to switch from the anti-inflammatory M2 phenotype to the pro-inflammatory M1 phenotype. Additionally, we observed that macrophages induced by NETs containing HMGB1 can prompt CaCo-2 cell apoptosis and exacerbate the inflammatory response. HMGB1-containing NETs hinder tight junction protein expression in CaCo-2 cells by inducing macrophage M1 polarization, thereby impairing intestinal epithelial barrier function. Therefore, our findings indicate that by inhibiting the expression of HMGB1, the formation of NETs can be inhibited. This, in turn, mediates macrophage polarization and offers potential new therapies for intestinal diseases.
The ex vivo effects of hypoxanthine-tricyclano, a synthetic adenosine analogue, on rat left and right atria
Ovari I, Viczjan G, Bege M, Borbas A, Herczegh P, Zsuga J, Papp Z, Szilvassy Z, Juhasz B, Gesztelyi R and Erdei T
Hypoxanthine-tricyclano is a synthetic adenosine analogue, in which adenine and ribose have been replaced by hypoxanthine and a morpholino-derived tricyclic moiety, respectively. We investigated whether hypoxanthine-tricyclano could influence atrial inotropy and/or chronotropy, two important functions regulated by the A1 receptor, the main adenosine receptor type of the supraventricular myocardium. Paced left atria and spontaneously beating right atria, isolated from male, 30-35 weeks old, Wistar rats, were used. The ino- and chronotropic effects of adenosine and hypoxanthine-tricyclano (separately and together) were assessed in the absence and presence of 8-cyclopentyl-1,3-dipropylxanthine (CPX), a selective, orthosteric, reversible A1 adenosine receptor antagonist. We found that adenosine exerted a strong negative inotropic effect (similar in left and right atria). However, hypoxanthine-tricyclano elicited a moderate positive inotropic effect (also similar in all atria). In right atria, adenosine evoked a robust negative chronotropic effect, whereas hypoxanthine-tricyclano produced a slight positive chronotropy. CPX blunted the effects of both adenosine and hypoxanthine-tricyclano, although this antagonism was strong (and significant) for adenosine, while smaller (and non-significant) for hypoxanthine-tricyclano. Both effects of hypoxanthine-tricyclano were easily surmountable with adenosine. Thus, hypoxanthine-tricyclano may act as a week, orthosteric, reversible, inverse and low-affinity agonist of the A1 receptor, although alternative mechanisms of action cannot be excluded.
Anisodine hydrobromide injection promotes neural remodeling and recovery after ischemic stroke in mice
Men X, Ji H, Zhang C, Chen R, Zhang X, Xu R, Jiang W and Zhang X
Anisodine hydrobromide injection has shown promising therapeutic effects in treating patients with cerebral infarction, improving recovery of neurological function during the post-cerebral infarction period. However, the effects of anisodine hydrobromide on brain recovery and neuroplasticity are unclear. This study explores the therapeutic effects and underlying mechanisms of anisodine hydrobromide in mice experiencing the chronic phase of an ischemia stroke. The electrocautery method established a distal middle cerebral artery occlusion (MCAO) model in healthy male C57BL/6 mice. Neurological deficits were evaluated using Golgi and immunofluorescence staining to measure the effects of anisodine hydrobromide on neural proliferation, migration and remodeling. DAPT (dipeptidic γ-secretase-specific inhibitor) was employed to explore the involvement of the Notch signaling pathway post-anisodine hydrobromide treatment. Compared to the control and MCAO groups, mice treated with anisodine hydrobromide showed improved post-stroke neurological function, increased neurite intersections, and dendritic spine density in the peri-infarct cortex. Anisodine hydrobromide also promoted neural cell regeneration which is dendritic and axonal structures and synaptic vesicle protein restructuring. Gap43, NGF, Notch1, and Hes1 protein level increased significantly in the ANI group provided inhibitor DAPT was absent. Anisodine hydrobromide can promote neurological function, neurotrophic factors, and neuroplasticity. Notch signaling pathways also impact the effects of anisodine hydrobromide on neural plasticity in ischemia stroke.
Complexity of electrodermal activity to mental stress is changed during adolescent age-period
Visnovcova Z, Ferencova N and Tonhajzerova I
Complexity characterizes behaviour of all physiological systems whose components interact in multiple ways usually quantified by entropy techniques. However, complexity analysis regarding electrodermal activity (EDA)-related sympathetic cholinergic nervous system is rare. Thus, we aimed to study EDA dynamics complexity changes from aspect of various embedding dimensions (m) and timescales (τ) (sample entropy (SampEn) with m ∈ <2,7>, and multiscale entropy (MSE) in τ ∈ <1,20>) in association with traditionally used EDA indices (skin conductance level (SCL) and non-specific skin conductance responses (NS.SCRs)) to mental stress (mental arithmetic test - MAT) in healthy participants at critical adolescent age. The cohort (total group) consisted of 60 adolescents (17.5 ± 0.5 yrs) divided into three groups: Group-1: early (13.1 ± 0.3 yrs), Group-2: middle (16.6 ± 0.2 yrs) and Group-3: late (22.9 ± 0.1 yrs) adolescence. SampEn (m > 2) and MSE (for all τ) were significantly higher during MAT than baseline in total group and Group-2 (p < 0.05). Index MSE for all τ was significantly higher during MAT than baseline in total group, and Group-2; for τ ∈ <2,13> in Group-1 (p < 0.05). Additionally, while SCL was significantly higher during MAT than baseline in all groups, NS.SCRs was lower during stress only in Group-3 (p < 0.05). In conclusion, this study revealed distinct EDA complexity characteristics in individual examined groups indicating importance of complexity evaluation in stress-related sympathetic regulatory mechanisms within individual adolescent age ranges.
Silencing lncRNA SIX3OS1 mitigates inflammation and apoptosis in post-stroke cognitive impairment via miR-511-3p
Zeng J, Yang F, Xiao H, Zhao W, Song K, Liu Y and Wang T
The present study aimed to explore the expression and molecular mechanisms of lncRNA SIX3OS1 in post-stroke cognitive impairment (PSCI). Middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation/reoxygenation (OGD/R) were applied to establish an in vitro and in vivo model of PSCI. RT-qPCR was conducted to examine the mRNA levels of SIX3OS1, miR-511-3p, and RBP4. Morris water maze test was used to evaluate spatial learning and memory ability. Cell viability and apoptosis were examined by CCK-8 and flow cytometry. The secretion level of inflammatory factors was analyzed by ELISA. DLR and RIP assay were performed to validate the target relationship. In MCAO rats and OGD/R-induced cells, SIX3OS1 and RBP4 levels were significantly elevated, while miR-511-3p was reduced. miR-511-3p targets SIX3OS1 and RBP4. Compared with the sham, the spatial learning and memory ability of MCAO rats were decreased, but the silencing of SIX3OS1 could restore them, but this restoration was partially impaired by lowing of miR-511-3p. Silencing of SIX3OS1 enhanced OGD/R-induced SH-SY5Y cell viability and inhibited apoptosis and inflammatory factor secretion, but they were both attenuated by the lowing of miR-511-3p. Silencing of SIX3OS1 can protect PSCI via targeting miR-511-3p to promote cell viability and inhibit apoptosis and inflammation.
Effect of hypoxia and KCl depolarization in autofluorescence and ROS changes at the hippocampal CA3 area
Batista MI, Miranda CM, Figueiredo SM, Bosio M, Alves JL, Sousa MS, Sampaio-Dos-Aidos FD, Matias CM, Quinta-Ferreira RM and Quinta-Ferreira ME
The increasing incidence of neurodegenerative and other diseases is considered to involve an excessive production of reactive oxygen species (ROS). Water supplies are often characterized by excessive organic waste that is decomposed by bacteria, using dissolved oxygen, leading to oxygen depletion. The potassium content of these waters may also affect negatively the mitochondrial metabolism and cellular ROS formation. This work focused on characterizing mitochondrial autofluorescence changes, with flavoprotein origin, and fluorescence ROS signals measured using the 2',7'-dichlorodihydrofluorescein diacetate indicator H2DCFDA. All signals were evoked by hypoxia or by the depolarizing agent KCl (20 mM), at the hippocampal mossy fiber synapses of CA3 area. It was observed that both hypoxia and KCl-induced depolarization elicited a small rise in the autofluorescence and ROS changes. The hypoxia-induced signals were maintained upon normal reoxygenation, but of those evoked by KCl, the autofluorescence signals recovered during washout, while the ROS changes were irreversible.
Extremely low frequency pulsed magnetic field inhibits myocardial damage and apoptosis in rats with CLP-induced sepsis: A histopathological and immunohistochemical evaluation
Gürgül S, Gevrek F, Yelli S, Şeker FB and Demirel C
We aimed to investigate whether pulsed magnetic fields (PMFs) (1 mT) may have preventive effects on myocardial damage and apoptosis in rats with sepsis. Twenty-eight adult Wistar albino rats were evenly distributed among four experimental groups, each consisting of seven rats: SH, LF-PMF, HF-PMF, and CLP. Sepsis induction was carried out via the cecal ligation and puncture (CLP) method, while rats in the LF-PMF and HF-PMF groups were exposed to 7.5 Hz and 15 Hz PMF, respectively, for duration of 24 hours. Following the removal of heart tissue, histological techniques were employed for the analysis. Histological scoring of apoptosis-related Bax, Bcl-2, and Acas-3 proteins as well as cTnI were performed in the heart tissue. The myocardial damage score significantly increased in the CLP group compared to the SH group (p < 0.05). Significant decreases were observed in Bcl-2 and cTnI protein levels in the CLP group, while significant increases were detected in the PMF groups (p < 0.05). An increase in Bax and Acas-3 protein levels, as well as the Bax/Bcl-2 ratio, was observed in the CLP group, with a decrease in the PMF groups (p < 0.05). The results demonstrate that PMF application has anti-apoptotic and therapeutic effects on septic heart tissue damage.
Peripheral nesfatin-1 reduces basal brain activity but has limited effect on epilepsy-like conditions
Faruk Kalkan Ö, Aktaş O, Şahin Z, Aydin Abidin S, Yildirim A, Faruk Özyaşar A, Uzun İ and Abidin İ
In this study, we investigated the effects of peripheral nesfatin-1 on basal brain activity and 4-aminopyridine (4-AP)-induced epileptiform activity, and its relationship with the electrocorticogram (ECoG) power spectrum and EEG bands. Forty-nine male Wistar rats were divided into seven groups: control sham, 4-AP (2.5 mg/kg i.p.), Nesfatin-1 (1, 2, and 4 μg/kg i.p.), Nesfatin-1 (2 μg/kg) post-treatment, and Nesfatin-1 (2 μg/kg) pre-treatment. Recordings were conducted for 70 min under ketamine/xylazine (90/10 mg/kg) anesthesia. In the post-treatment group, nesfatin-1 was injected 20 min after 4-AP induction. In the pre-treatment groups, nesfatin-1 was administered following basal recordings and before 4-AP injection. 4-AP induced epileptiform activity in all animals, peaking at 30 min. Nesfatin-1 (2 μg/kg) reduced basal brain activity (p < 0.05) and decreased alpha, delta, and theta bands in ECoG. Post-treatment of nesfatin-1 did not affect 4-AP-induced activity (p > 0.05) but increased gamma band activity (p > 0.05). Pre-treatment of nesfatin-1 reduced epileptiform activity between 50 and 60 min (p < 0.05), decreased delta bands, and increased gamma bands (p > 0.05). We conclude that peripheral nesfatin-1 modulates normal brain activity but has limited effects on abnormal discharges.
PVT1 regulates hippocampal neuron apoptosis and inflammation in epilepsy by miR-206-3p-dependent regulation of CAMK4
Li C, Li R, Bai X and Jiang H
This study was designed to dissect the function of plasmacytoma variant translocation 1 (PVT1) in hippocampal neuron injury in epilepsy and its possible molecular basis. Status epilepticus (SE) mouse model was built and primary hippocampal neurons were isolated. qRT-PCR and Western blot were applied to quantify the levels of related genes and proteins. Cell proliferation and apoptosis were examined by CCK-8, EdU, and flow cytometry assays. Inflammatory factors were detected using ELISA analysis. Dual-luciferase reporter and RIP assays were carried out to validate the relationship between miR-206-3p and PVT1 or CAMK4. PVT1 and CAMK4 were increased, and miR-206-3p was downregulated in the hippocampus and hippocampal neurons of SE mice. Knockdown of PVT1 or CAMK4 abated SE-induced proliferation inhibition, apoptosis, and inflammation in hippocampal neurons. Mechanistically, PVT1 could sponge miR-206-3p to upregulate the expression of CAMK4 in hippocampal neurons. Moreover, downregulation of miR-206-3p reversed the inhibitory effects of PVT1 knockdown on SE-induced apoptosis and inflammation in hippocampal neurons. Similarly, overexpression of CAMK4 abolished miR-206-3p-evoked arrest of apoptosis and inflammation in hippocampal neurons under SE condition. Collectively, PVT1 contributed to SE-induced apoptosis and inflammation in hippocampal neurons by modulating the miR-206-3p/CAMK4 axis, offering a novel insight into the prevention of epilepsy.
Cytotoxic and pro-oxidant profile of a photosensitive ruthenium nitrosyl candidate for NO delivery in healthy human fibroblasts
Özbaşak H, Elbeheiry HM, Schulz M and Račková L
Ruthenium nitrosyl (Ru-NO) complexes are of interest as photoactive nitric oxide (NO) donor candidates for local therapeutic applications. NO plays a crucial regulatory role in skin homeostasis, concentration-dependently affecting processes like the proliferation, apoptosis, autophagy and redox balance. In this context, we investigated HE-10, a ruthenium-based photoinducible NO donor, for its pro-oxidant and cytotoxic effects under light and dark conditions in VH10 human foreskin fibroblast cells. We also tested its intracellular and extracellular NO-releasing function. Our study reveals a significant dose-dependent cytotoxic effect of HE-10, an increase in intracellular reactive oxygen and nitrogen species, and the occurrence of apoptosis in skin fibroblast cells. Furthermore, exposure to both increasing doses of HE-10 and white LED light led to substantial cellular events, including a significant induction of autophagy and G2/M phase cell cycle arrest. Paradoxically, these effects were not solely attributable to NO release based on DAF2-DA NO probe results, suggesting that intracellular photochemical reactions additional to NO photolysis contribute to HE-10's biological activity. This study shows that HE-10 exhibits both cytotoxic and potential therapeutic effects, depending on concentration and light exposure. These findings are crucial for developing targeted Ru-NO complex treatments for skin diseases and potentially certain types of skin cancer, where controlled NO release could be beneficial.