Cytochrome c as a Potentially Clinical Useful Marker of Mitochondrial and Cellular Damage

The effect of cytochrome c on Na,K-ATPase

Na,K-ATPase is a crucial enzyme responsible for maintaining Na+, K+-gradients across the cell membrane, which is essential for numerous physiological processes within various organs and tissues. Due to its significance in cellular physiology, inhibiting Na,K-ATPase can have profound physiological consequences. This characteristic makes it a target for various pharmacological applications, and drugs that modulate the pump's activity are thus used in the treatment of several medical conditions. Cytochrome c (Cytc) is a protein with dual functions in the cell. In the mitochondria, it is essential for ATP synthesis and energy production. However, in response to apoptotic stimuli, it is released into the cytosol, where it triggers programmed cell death through the intrinsic apoptosis pathway. Aside from its role in canonical intrinsic apoptosis, Cytc also plays additional roles. For instance, Cytc participates in certain non-apoptotic functions -those which are less well-understood in comparison to its role in apoptosis. Within this in vitro study, we have shown the impact of Cytc on Na,K-ATPase for the first time. Cytc has a biphasic action on Na,K-ATPase, with activation at low concentrations (0.06 ng/ml; 6 ng/ml) and inhibition at high concentration (120 ng/ml). Cytc moreover displays isoform/subunit specificity and regulates the Na+ form of the enzyme, while having no effect on the activity or kinetic parameters of the K+-dependent form of the enzyme. Changing the affinity of p-chloromercuribenzoic acid (PCMB) by Cytc is therefore both a required and sufficient condition for confirming that PCMB and Cytc share the same target, namely the thiol groups of cysteine in Na,K-ATPase.

Pirh2 modulates the mitochondrial function and cytochrome c-mediated neuronal death during Alzheimer's disease

Pirh2 is an E3 ubiquitin ligase known to regulate the DNA damage responses through ubiquitylation of various participating signaling factors. DNA damage is a key pathological contributor to Alzheimer's disease (AD), therefore, the role of Pirh2 was investigated in streptozotocin and oligomer Aβ1-42 induced rodent experimental model of AD. Pirh2 protein abundance increased during AD conditions, and transient silencing of Pirh2 inhibited the disease-specific pathological markers like level of p-Tau, βamyloid, acetylcholinesterase activity, and neuronal death. Biochemically, Pirh2 silencing significantly attenuated the oxidative stress, depleted mitochondrial membrane potential, cytochrome c translocation from mitochondria to cytosol, and depleted mitochondrial complex-I activity, and ATP level. Pirh2 silencing also inhibited the altered level of VDAC1, hsp75, hexokinase1, t-Bid, caspase-9, and altered level of apoptotic proteins (Bcl-2, Bax). MALDI-TOF/TOF, co-immunoprecipitation, and UbcH13-linked ubiquitylation assay confirmed the interaction of Pirh2 with cytochrome c and the role of Pirh2 in ubiquitylation of cytochrome c, along with Pirh2-dependent altered proteasome activity. Additionally, Pirh2 silencing further inhibited the translocation of mitochondrion-specific endonuclease G and apoptosis-inducing factors to the nucleus and DNA damage. In conclusion, findings suggested the significant implication of Pirh2 in disease pathogenesis, particularly through impaired mitochondrial function, including biochemical alterations, translocation of cytochrome c, endonuclease G and apoptosis-inducing factor, DNA damage, and neuronal apoptosis.

The Antioxidant and anti-inflammatory Activity of Selenium and Lecithin Combination Against ethanol-induced Gastric Ulcer in mice via Modulating IGF-1/PTEN/Akt/FoxO3a Signaling

Gastric ulcers are one of the most prevalent gastrointestinal disorders. The current study investigated the antioxidant and anti-inflammatory effects of selenium (Se) and lecithin (Lec) alone and in combination against ethanol-induced gastric ulcers in mice, and their ability to modulate insulin-like growth factor-1 (IGF-1)/ Phosphatase and tensin homologue deleted on chromosome 10 (PTEN)/ Protein kinase B (Akt)/ Forkhead box O3a (FoxO3a) signaling. The mice were divided into normal, ethanol, Se + ethanol, Lec + ethanol, Se + Lec + ethanol, and omeprazole + ethanol groups. Treatment with the selected doses was continued for 14 days before a single dose of absolute ethanol (5 ml/kg body weight) was administered to induce gastric ulcers in mice. The results showed that pretreatment with Se and Lec combination effectively decreased both the macro- and microscopic gastric lesions and increased the protection index compared to the ethanol group. Remarkably, the Se and Lec combination decreased the levels of reactive oxygen species, malondialdehyde, and cytochrome c and increased glutathione, glutathione peroxidase, and thioredoxin reductase activities in gastric tissues. The Se and Lec combination increased prostaglandin E2 and interleukin-10 levels but decreased tumor necrosis factor-α, interleukin-6 and interleukin-1β levels compared to either treatment alone. Interestingly, this combination decreased the expression of IGF-1, p-Akt, and FoxO3a proteins and increased PTEN expression in gastric tissues. The gastric tissues examination by hematoxylin and eosin staining confirmed these results. Therefore, the Se and Lec combination showed superior protective effects against ethanol-induced gastric ulcers in mice, compared to either treatment alone, through antioxidant, and anti-inflammatory activities, in addition to modulating IGF-1/PTEN/Akt/FoxO3a pathway signaling.

Citalopram, an antipsychotic agent, induces G1/G0 phase cell cycle arrest and promotes apoptosis in human laryngeal carcinoma HEP-2 cells

Human laryngeal squamous carcinoma (LSCC) is a common malignant tumor in the head and neck. Despite the recently developed therapies for the treatment of LSCC, patients' overall survival rate still did not enhance remarkably; this highlights the need to formulate alternative strategies to develop novel treatments. The antitumor effects of antidepressant drugs such as citalopram have been reported on several cancer cells; however, they have yet to be investigated against LSCC. The current study was directed to explore the possible antitumor effects of citalopram on human laryngeal carcinoma cell lines (HEP-2). HEP-2 cells were cultured and treated with different doses of citalopram (50-400 µM) for 24, 48, and 72 h. The effects of citalopram on the viability of cancer cells were determined by the MTT assay. In addition, apoptosis and cell cycle analysis were performed by flow cytometry. Moreover, evaluation of the expression of proapoptotic and apoptotic proteins, such as cytochrome c, cleaved caspases 3 and 9, Bcl-2, and BAX, was performed by western blotting analysis. Our results revealed that citalopram significantly suppressed the proliferation of HEP-2 cells through the upregulation of p21 expression, resulting in the subsequent arrest of the cell cycle at the G0/G1 phase. Furthermore, citalopram treatment-induced HEP-2 cell apoptosis; this was indicated by the significant increase of cytochrome c, cleaved caspases 3 and 9, and BAX protein expression. On the contrary, Bcl-2 protein expression was significantly downregulated following treatment with citalopram. The ultrastructure studies were in accordance with the protein expression findings and showed clear signs of apoptosis with ring chromatin condensation upon treatment with citalopram. These findings suggest that citalopram's anti-tumor activities on HEP-2 cells entailed stimulation of the intrinsic apoptotic pathway, which was mediated via Bcl-2 suppression.

Unlocking the Mitochondria for Nanomedicine-based Treatments: Overcoming Biological Barriers, Improving Designs, and Selecting Verification Techniques

Enhanced targeting approaches will support the treatment of diseases associated with dysfunctional mitochondria, which play critical roles in energy generation and cell survival. Obstacles to mitochondria-specific targeting include the presence of distinct biological barriers and the need to pass through (or avoid) various cell internalization mechanisms. A range of studies have reported the design of mitochondrially-targeted nanomedicines that navigate the complex routes required to influence mitochondrial function; nonetheless, a significant journey lies ahead before mitochondrially-targeted nanomedicines become suitable for clinical use. Moving swiftly forward will require safety studies, in vivo assays confirming effectiveness, and methodologies to validate mitochondria-targeted nanomedicines' subcellular location/activity. From a nanomedicine standpoint, we describe the biological routes involved (from administration to arrival within the mitochondria), the features influencing rational design, and the techniques used to identify/validate successful targeting. Overall, rationally-designed mitochondria-targeted-based nanomedicines hold great promise for precise subcellular therapeutic delivery.

Cardiac damage and tropism of severe acute respiratory syndrome coronavirus 2

Until now, the World Health Organization registered over 771 million cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection worldwide, of which 6.97 million resulted in death. Virus-related cardiovascular events and pre-existing heart problems have been identified as major contributing factors to global infection-related morbidity and mortality, emphasizing the necessity for risk assessment and future prevention. In this review, we highlight cardiac manifestations that might arise from an infection with SARS-CoV-2 and provide an overview of known comorbidities that worsen the outcome. Additionally, we aim to summarize the therapeutic strategies proposed to reverse virus-associated myocardial damage, which will be further highlighted in this review, with an outlook to successful recovery and prevention.

Microcirculation-driven mitochondrion dysfunction during the progression of experimental sepsis

Sepsis is accompanied by a less-known mismatch between hemodynamics and mitochondrial respiration. We aimed to characterize the relationship and time dependency of microcirculatory and mitochondrial functions in a rodent model of intraabdominal sepsis. Fecal peritonitis was induced in rats, and multi-organ failure (MOF) was evaluated 12, 16, 20, 24 or 28 h later (n = 8/group, each) using rat-specific organ failure assessment (ROFA) scores. Ileal microcirculation (proportion of perfused microvessels (PPV), microvascular flow index (MFI) and heterogeneity index (HI)) was monitored by intravital video microscopy, and mitochondrial respiration (OxPhos) and outer membrane (mtOM) damage were measured with high-resolution respirometry. MOF progression was evidenced by increased ROFA scores; microcirculatory parameters followed a parallel time course from the 16th to 28th h. Mitochondrial dysfunction commenced with a 4-h time lag with signs of mtOM damage, which correlated significantly with PPV, while no correlation was found between HI and OxPhos. High diagnostic value was demonstrated for PPV, mtOM damage and lactate levels for predicting MOF. Our findings indicate insufficient splanchnic microcirculation to be a possible predictor for MOF that develops before the start of mitochondrial dysfunction. The adequate subcellular compensatory capacity suggests the presence of mitochondrial subpopulations with differing sensitivity to septic insults.

When Our Best Friend Becomes Our Worst Enemy: The Mitochondrion in Trauma, Surgery, and Critical Illness

Common for major surgery, multitrauma, sepsis, and critical illness, is a whole-body inflammation. Tissue injury is able to trigger a generalized inflammatory reaction. Cell death causes release of endogenous structures termed damage associated molecular patterns (DAMPs) that initiate a sterile inflammation. Mitochondria are evolutionary endosymbionts originating from bacteria, containing molecular patterns similar to bacteria. These molecular patterns are termed mitochondrial DAMPs (mDAMPs). Mitochondrial debris released into the extracellular space or into the circulation is immunogenic and damaging secondary to activation of the innate immune system. In the circulation, released mDAMPS are either free or exist in extracellular vesicles, being able to act on every organ and cell in the body. However, the role of mDAMPs in trauma and critical care is not fully clarified. There is a complete lack of knowledge how they may be counteracted in patients. Among mDAMPs are mitochondrial DNA, cardiolipin, N-formyl peptides, cytochrome C, adenosine triphosphate, reactive oxygen species, succinate, and mitochondrial transcription factor A. In this overview, we present the different mDAMPs, their function, release, targets, and inflammatory potential. In light of present knowledge, the role of mDAMPs in the pathophysiology of major surgery and trauma as well as sepsis, and critical care is discussed.

Nitrogen-Vacancy Magnetic Relaxometry of Nanoclustered Cytochrome C Proteins

Nitrogen-vacancy (NV) magnetometry offers an alternative tool to detect paramagnetic centers in cells with a favorable combination of magnetic sensitivity and spatial resolution. Here, we employ NV magnetic relaxometry to detect cytochrome C (Cyt-C) nanoclusters. Cyt-C is a water-soluble protein that plays a vital role in the electron transport chain of mitochondria. Under ambient conditions, the heme group in Cyt-C remains in the Fe3+ state, which is paramagnetic. We vary the concentration of Cyt-C from 6 to 54 μM and observe a reduction of the NV spin-lattice relaxation time (T1) from 1.2 ms to 150 μs, which is attributed to the spin noise originating from the Fe3+ spins. NV T1 imaging of Cyt-C drop-casted on a nanostructured diamond chip allows us to detect the relaxation rates from the adsorbed Fe3+ within Cyt-C.

Mitochondrial Dysfunction in Endothelial Progenitor Cells: Unraveling Insights from Vascular Endothelial Cells

Endothelial dysfunction is associated with several lifestyle-related diseases, including cardiovascular and neurodegenerative diseases, and it contributes significantly to the global health burden. Recent research indicates a link between cardiovascular risk factors (CVRFs), excessive production of reactive oxygen species (ROS), mitochondrial impairment, and endothelial dysfunction. Circulating endothelial progenitor cells (EPCs) are recruited into the vessel wall to maintain appropriate endothelial function, repair, and angiogenesis. After attachment, EPCs differentiate into mature endothelial cells (ECs). Like ECs, EPCs are also susceptible to CVRFs, including metabolic dysfunction and chronic inflammation. Therefore, mitochondrial dysfunction of EPCs may have long-term effects on the function of the mature ECs into which EPCs differentiate, particularly in the presence of endothelial damage. However, a link between CVRFs and impaired mitochondrial function in EPCs has hardly been investigated. In this review, we aim to consolidate existing knowledge on the development of mitochondrial and endothelial dysfunction in the vascular endothelium, place it in the context of recent studies investigating the consequences of CVRFs on EPCs, and discuss the role of mitochondrial dysfunction. Thus, we aim to gain a comprehensive understanding of mechanisms involved in EPC deterioration in relation to CVRFs and address potential therapeutic interventions targeting mitochondrial health to promote endothelial function.

The cardioprotective effects of cerium oxide nanoparticles against the poisoning generated by aluminum phosphide pesticide: Controlling oxidative stress and mitochondrial damage

BACKGROUND

Aluminum phosphide (AlP) is a well-known toxic compound used as an agricultural pesticide to prevent insect damage to stored crops. However, even if just a small amount was consumed, it caused lasting harm to the human body and, in acute concentrations, death. The current study employed cerium oxide nanoparticles (CeO2 NPs) to reduce oxidative stress and various harmful outcomes of AlP poisoning.

METHODS

Following finding effective concentrations of CeO2 NPs via MTT assay, Human Cardiac Myocyte (HCM) cells were pre-treated with CeO2 NPs for 24 h. After that, they were exposed to 2.36 μM AlP. The activity of oxidative stress and mitochondrial biomarkers, including mitochondrial swelling, mitochondrial membrane potential, and cytochrome c release, were evaluated in HCM cells. Finally, the population of apoptotic and necrotic cells was assessed via flow cytometry.

RESULTS

After 24 h, data revealed that all tested concentrations of CeO2 NPs were safe, and 25 and 50 μM of that were selected as effective concentrations. Oxidative stress markers (malondialdehyde, protein carbonyl, superoxide dismutase, and catalase) showed that CeO2 NPs could successfully decrease AlP poisoning due to their antioxidant characteristics. Mitochondrial markers were also recovered by pre-treatment of HCM cells with CeO2 NPs. Furthermore, pre-treating with CeO2 NPs could compensate for the reduction of live cells with AlP and cause a diminishing in the population of early and late apoptotic cells.

CONCLUSION

As a result, it is evident that CeO2 NPs, through the recovery of oxidative stress and mitochondrial damages caused by AlP, reduce apoptosis and have therapeutic potentials on HCM cells.

Mitochondrial damage-associated molecular patterns in chronic obstructive pulmonary disease: Pathogenetic mechanism and therapeutic target

Chronic obstructive pulmonary disease (COPD) is a common inflammatory airway disease characterized by enhanced inflammation. Recent studies suggest that mitochondrial damage-associated molecular patterns (DAMPs) may play an important role in the regulation of inflammation and are involved in a serial of inflammatory diseases, and they may also be involved in COPD. This review highlights the potential role of mitochondrial DAMPs during COPD pathogenesis and discusses the therapeutic potential of targeting mitochondrial DAMPs and their related signaling pathways and receptors for COPD. Research progress on mitochondrial DAMPs may enhance our understanding of COPD inflammation and provide novel therapeutic targets.

An enhanced label-free proteomics approach for deep-diving into equine plasma proteome, including the discovery of protein biomarkers for strenuous exercise

Plasma proteins have been a valuable source of biomarkers for clinical uses and for monitoring of the illicit use of prohibited substances or practices in equine sports. We have previously reported the first use of label-free proteomics in profiling equine plasma proteome. This study aimed to refine the method by systematically evaluating various plasma fractionation methods and the use of narrower precursor mass ranges in data-independent acquisition (DIA) mass spectrometry (MS). Tandem fractionations of equine plasma with octanoic acid precipitation followed by solid-phase extraction (SPE) with C4 cartridges provided the largest increase in the number of new proteins identified. The use of two narrow precursor mass ranges of m/z 400-600 and 600-800 in DIA not only identified most proteins detectable by using a single mass range of m/z 350-1500 but also identified ~27% more proteins. The improved method was applied to analyse the plasma proteome of 'postrace' samples which, unlike other samples, had been collected from racehorses soon after racing. Multivariate data analysis has identified upregulation of 14 proteins and downregulation of six proteins in postrace plasma compared with the non-postrace plasma samples. Literature review of these proteins has provided evidence of exercise-induced haemolysis and changes in antioxidant enzyme activities, kinin system, insulin signalling and energy metabolism after strenuous exercise. The improved method has enabled a deeper profiling of the equine plasma proteome and identified the proteins associated with normal physiological changes after racing which are potential confounding factors in the development of a biomarker approach for doping control.

Effect of COVID-19 mRNA Vaccine on Human Lung Carcinoma Cells In Vitro by Means of Raman Spectroscopy and Imaging

The effect of COVID-19 mRNA vaccine on human lung epithelial carcinoma cells (A549) in vitro as a convenient preclinical model was studied by means of Raman spectroscopy and imaging. The article focuses on Raman imaging as a tool to explore apoptosis and oxidative phosphorylation in mitochondrial dysfunctions. The Raman results demonstrate alterations in the oxidation-reduction pathways associated with cytochrome c. We found that the COVID-19 mRNA vaccine downregulates the concentration of cytochrome c upon incubation with tumorous lung cells. The concentration of the oxidized form of cytochrome c in the mitochondria of lung cells decreases upon incubation with the COVID-19 mRNA vaccine. A lower concentration of oxidized cytochrome c in mitochondria illustrates lower effectiveness of oxidative phosphorylation (respiration), reduced apoptosis, and lessened ATP production. Moreover, mRNA vaccine significantly increases de novo lipids synthesis in lipid droplets up to 96 h and alterations in biochemical composition. It seems that the lipid composition of cells returns to the normal level for a longer incubation time (14 days). In the cell nucleus, the mRNA vaccine does not produce statistically significant changes.

Characterisation of macrophage infiltration and polarisation based on integrated transcriptomic and histological analyses in Primary Sjögren's syndrome

Background

Primary Sjögren's syndrome (pSS) is a progressive inflammatory autoimmune disease. Immune cell infiltration into glandular lobules and ducts and glandular destruction are the pathophysiological hallmarks of pSS. Macrophages are one of the most important cells involved in the induction and regulation of an inflammatory microenvironment. Although studies have reported that an abnormal tissue microenvironment alters the metabolic reprogramming and polarisation status of macrophages, the mechanisms driving macrophage infiltration and polarisation in pSS remain unclear.

Methods

Immune cell subsets were characterised using the single-cell RNA sequencing (scRNA-seq) data of peripheral blood mononuclear cells (PBMCs) from patients with pSS (n = 5) and healthy individuals (n = 5) in a public dataset. To evaluate macrophage infiltration and polarisation in target tissues, labial salivary gland biopsy tissues were subjected to histological staining and bulk RNA-seq (pSS samples, n = 24; non-pSS samples, n = 12). RNA-seq data were analysed for the construction of macrophage co-expression modules, enrichment of biological processes and deconvolution-based screening of immune cell types.

Results

Detailed mapping of PBMCs using scRNA-seq revealed five major immune cell subsets in pSS, namely, T cells, B cells, natural killer (NK) cells, dendritic cells (DCs) and monocyte-macrophages. The monocyte-macrophage subset was large and had strong inflammatory gene signatures. This subset was found to play an important role in the generation of reactive oxygen species and communicate with other innate and adaptive immune cells. Histological staining revealed that the number of tissue-resident macrophages was high in damaged glandular tissues, with the cells persistently surrounding the tissues. Analysis of RNA-seq data using multiple algorithms demonstrated that the high abundance of pro-inflammatory M1 macrophages was accompanied by the high abundance of other infiltrating immune cells, senescence-associated secretory phenotype and evident metabolic reprogramming.

Conclusion

Macrophages are among the most abundant innate immune cells in PBMCs and glandular tissues in patients with pSS. A bidirectional relationship exists between macrophage polarisation and the inflammatory microenvironment, which may serve as a therapeutic target for pSS.

Hepatocyte FBXW7-dependent activity of nutrient-sensing nuclear receptors controls systemic energy homeostasis and NASH progression in male mice

Nonalcoholic steatohepatitis (NASH) is epidemiologically associated with obesity and diabetes and can lead to liver cirrhosis and hepatocellular carcinoma if left untreated. The intricate signaling pathways that orchestrate hepatocyte energy metabolism and cellular stress, intrahepatic cell crosstalk, as well as interplay between peripheral tissues remain elusive and are crucial for the development of anti-NASH therapies. Herein, we reveal E3 ligase FBXW7 as a key factor regulating hepatic catabolism, stress responses, systemic energy homeostasis, and NASH pathogenesis with attenuated FBXW7 expression as a feature of advanced NASH. Multiomics and pharmacological intervention showed that FBXW7 loss-of-function in hepatocytes disrupts a metabolic transcriptional axis conjointly controlled by the nutrient-sensing nuclear receptors ERRα and PPARα, resulting in suppression of fatty acid oxidation, elevated ER stress, apoptosis, immune infiltration, fibrogenesis, and ultimately NASH progression in male mice. These results provide the foundation for developing alternative strategies co-targeting ERRα and PPARα for the treatment of NASH.

Functionalized Gold Nanoparticles Suppress the Proliferation of Human Lung Alveolar Adenocarcinoma Cells by Deubiquitinating Enzymes Inhibition

Functionalized gold nanoparticles (AuNPs) are widely used in therapeutic applications, but little is known regarding the impact of their surface functionalization in the process of toxicity against cancer cells. This study investigates the anticancer effects of 5 nm spherical AuNPs functionalized with tannate, citrate, and PVP on deubiquitinating enzymes (DUBs) in human lung alveolar adenocarcinoma (A549) cells. Our findings show that functionalized AuNPs reduce the cell viability in a concentration- and time-dependent manner as measured by modified lactate dehydrogenase (mLDH) and 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assays. An increased generation of intracellular reactive oxygen species (ROS) and depletion of glutathione (GSH/GSSG) ratio was observed with the highest AuNP concentration of 10 μg/mL. The expression of DUBs such as ubiquitin specific proteases (USP7, USP8, and USP10) was slightly inhibited when treated with concentrations above 2.5 μg/mL. Moreover, functionalized AuNPs showed an inhibitory effect on protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) and wingless-related integration site (Wnt) signaling proteins, and this could further trigger mitochondrial related-apoptosis by the upregulation of caspase-3, caspase-9, and PARP in A549 cells. Furthermore, our study shows a mechanistic understanding of how functionalized AuNPs inhibit the DUBs, consequently suppressing cell proliferation, and can be modulated as an approach toward anticancer therapy. The study also warrants the need for future work to investigate the effect of functionalized AuNPs on DUB on other cancer cell lines both in vitro and in vivo.

Cross-reactivity and sequence similarity between microbial transglutaminase and human tissue antigens

Microbial transglutaminase (mTG) is a bacterial survival factor, frequently used as a food additive to glue processed nutrients. As a result, new immunogenic epitopes are generated that might drive autoimmunity. Presently, its contribution to autoimmunity through epitope similarity and cross-reactivity was investigated. Emboss Matcher was used to perform sequence alignment between mTG and various antigens implicated in many autoimmune diseases. Monoclonal and polyclonal antibodies made specifically against mTG were applied to 77 different human tissue antigens using ELISA. Six antigens were detected to share significant homology with mTG immunogenic sequences, representing major targets of common autoimmune conditions. Polyclonal antibody to mTG reacted significantly with 17 out of 77 tissue antigens. This reaction was most pronounced with mitochondrial M2, ANA, and extractable nuclear antigens. The results indicate that sequence similarity and cross-reactivity between mTG and various tissue antigens are possible, supporting the relationship between mTG and the development of autoimmune disorders 150W.

Hypoosmosis alters hepatocyte mitochondrial morphology and induces selective release of carbamoyl phosphate synthetase 1

Carbamoyl phosphate synthetase 1 (CPS1) is the most abundant hepatocyte mitochondrial matrix protein. Hypoosmotic stress increases CPS1 release in isolated mouse hepatocytes without cell death. We hypothesized that increased CPS1 release during hypoosmosis is selective and associates with altered mitochondrial morphology. Both ex vivo and in vivo models were assessed. Mouse hepatocytes and livers were challenged with isotonic or hypoosmotic (35 mosM) buffer. Mice were injected intraperitoneally with water (10% body weight) with or without an antidiuretic. Mitochondrial and cytosolic fractions were isolated using differential centrifugation, then analyzed by immunoblotting to assess subcellular redistribution of four mitochondrial proteins: CPS1, ornithine transcarbamylase (OTC), pyrroline-5-carboxylate reductase 1 (PYCR1), and cytochrome c. Mitochondrial morphology alterations were examined using electron microscopy. Hypoosmotic treatment of whole livers or hepatocytes led to preferential or increased mitochondrial release, respectively, of CPS1 as compared with two mitochondrial matrix proteins (OTC/PYCR1) and with the intermembrane space protein, cytochrome c. Mitochondrial apoptosis-induced channel opening using staurosporine in hepatocytes led to preferential CPS1 and cytochrome c release. The CPS1-selective changes were accompanied by dramatic alterations in ultrastructural mitochondrial morphology. In mice, hypoosmosis/hyponatremia led to increased liver vascular congestion and increased CPS1 in bile but not blood, coupled with mitochondrial structural alterations. In contrast, isotonic increase of intravascular volume led to a decrease in mitochondrial size with limited change in bile CPS1 compared with hypoosmotic conditions and absence of the hypoosmosis-associated histological alterations. Taken together, hepatocyte CPS1 is selectively released in response to hypoosmosis/hyponatremia and provides a unique biomarker of mitochondrial injury.NEW & NOTEWORTHY Exposure of isolated mouse livers, primary cultured hepatocytes, or mice to hypoosmosis/hyponatremia conditions induces significant mitochondrial shape alterations accompanied by preferential release of the mitochondrial matrix protein CPS1, a urea cycle enzyme. In contrast, the intermembrane space protein, cytochrome c, and two other matrix proteins, including the urea cycle enzyme ornithine transcarbamylase, remain preferentially retained in mitochondria. Therefore, hepatocyte CPS1 manifests unique mitochondrial stress response compartmentalization and is a sensitive sensor of mitochondrial hypoosmotic/hyponatremic injury.

Supplementation with EPA and DHA omega-3 fatty acids improves peripheral immune cell mitochondrial dysfunction and inflammation in subjects with obesity

Omega-3 fatty acids (w-3 FA) have anti-inflammatory effects and improve mitochondrial function. Nonetheless, little is known about their effect on mitochondrial bioenergetics of peripheral blood mononuclear cells (PBMCs) in individuals with obesity. Thus, this study aimed to determine the mitochondrial bioenergetics status and cell subset composition of PBMCs during obesity, before and after 1 month supplementation with w-3 FA. We performed a case-control study with twelve women with normal BMI (lean group) and 19 with grade 2 obesity (obese group), followed by a before-after prospective study where twelve subjects with obesity received a 1 month intervention with 5.25 g of w-3 FA (3.5 g eicosapentaenoic (EPA) and 1.75 g docosahexaenoic (DHA) acids), and obtained PBMCs from all participants. Mitochondrial bioenergetic markers, including basal and ATP-production associated respiration, proton leak, and nonmitochondrial respiration, were higher in PBMCs from the obese group vs. the lean group. The bioenergetic health index (BHI), a marker of mitochondrial function, was lower in the obese vs. the lean group. In addition, Th1, Th2, Th17, CD4+ Tregs, CD8+ Tregs, and Bregs, M1 monocytes and pDCreg cells were higher in PBMCs from the obese group vs. the lean group. The w-3 FA intervention improved mitochondrial function, mainly by decreasing nonmitochondrial respiration and increasing the reserve respiratory capacity and BHI. The intervention also reduced circulating pro-inflammatory and anti-inflammatory lymphocyte and monocytes subsets in individuals with obesity. The mitochondrial dysfunction of PBMCs and the higher proportion of peripheral pro-inflammatory and anti-inflammatory immune cells in subjects with obesity, improved with 1 month supplementation with EPA and DHA.

Impact of Surface Charge-Tailored Gold Nanorods for Selective Targeting of Mitochondria in Breast Cancer Cells Using Photodynamic Therapy

Herein, the impact of surface charge tailored of gold nanorods (GNRs) on breast cancer cells (MCF-7 and MDA-MB-231) upon conjugation with triphenylphosphonium (TPP) for improved photodynamic therapy (PDT) targeting mitochondria was studied. The salient features of the study are as follows: (i) positive (CTAB@GNRs) and negative (PSS-CTAB@GNRs) surface-charged gold nanorods were developed and characterized; (ii) the mitochondrial targeting efficiency of gold nanorods was improved by conjugating TPP molecules; (iii) the conjugated nanoprobes (TPP-CTAB@GNRs and TPP-PSS-CTAB@GNRs) were evaluated for PDT in the presence of photosensitizer (PS), 5-aminolevulinic acid (5-ALA) in breast cancer cells; (iv) both nanoprobes (TPP-CTAB@GNRs and TPP-PSS-CTAB@GNRs) induce apoptosis, damage DNA, generate reactive oxygen species, and decrease mitochondrial membrane potential upon 5-ALA-based PDT; and (v) 5-ALA-PDT of two nanoprobes (TPP-CTAB@GNRs and TPP-PSS-CTAB@GNRs) impact cell signaling (PI3K/AKT) pathway by upregulating proapoptotic genes and proteins. Based on the results, we confirm that the positively charged (rapid) nanoprobes are more advantageous than their negatively (slow) charged nanoprobes. However, depending on the kind and degree of cancer, both nanoprobes can serve as efficient agents for delivering anticancer therapy.

Vapor-Phase Synthesis of Molecularly Imprinted Polymers on Nanostructured Materials at Room-Temperature

Molecularly imprinted polymers (MIPs) have recently emerged as robust and versatile artificial receptors. MIP synthesis is carried out in liquid phase and optimized on planar surfaces. Application of MIPs to nanostructured materials is challenging due to diffusion-limited transport of monomers within the nanomaterial recesses, especially when the aspect ratio is >10. Here, the room temperature vapor-phase synthesis of MIPs in nanostructured materials is reported. The vapor phase synthesis leverages a >1000-fold increase in the diffusion coefficient of monomers in vapor phase, compared to liquid phase, to relax diffusion-limited transport and enable the controlled synthesis of MIPs also in nanostructures with high aspect ratio. As proof-of-concept application, pyrrole is used as the functional monomer thanks to its large exploitation in MIP preparation; nanostructured porous silicon oxide (PSiO2 ) is chosen to assess the vapor-phase deposition of PPy-based MIP in nanostructures with aspect ratio >100; human hemoglobin (HHb) is selected as the target molecule for the preparation of a MIP-based PSiO2 optical sensor. High sensitivity and selectivity, low detection limit, high stability and reusability are achieved in label-free optical detection of HHb, also in human plasma and artificial serum. The proposed vapor-phase synthesis of MIPs is immediately transferable to other nanomaterials, transducers, and proteins.

The Mechanism of Anti-Tumor Activity of 6-Morpholino- and 6-Amino-9-Sulfonylpurine Derivatives on Human Leukemia Cells

The aim of this study was to explore the mechanism of antitumor effect of (E)-6-morpholino-9-(styrylsulfonyl)-9H-purine (6-Morpholino-SPD) and (E)-6-amino-9-(styrylsulfonyl)-9H-purine (6-Amino-SPD). The effects on apoptosis induction, mitochondrial potential, and accumulation of ROS in treated K562 cells were determined by flow cytometry. The RT-PCR method was used to measure the expression of Akt, CA IX, caspase 3, and cytochrome c genes, as well as selected miRNAs. Western blot analysis was used to determine the expression of Akt, cytochrome c, and caspase 3. The results demonstrate the potential of the tested derivatives as effective antitumor agents with apoptotic-inducing properties. In leukemic cells treated with 6-Amino-SPD, increased expression of caspase 3 and cytochrome c genes was observed, indicating involvement of the intrinsic mitochondrial pathway in the induction of apoptosis. Conversely, leukemic cells treated with 6-Morpholino-SPD showed reduced expression of these genes. The observed downregulation of miR-21 by 6-Morpholino-SPD may contribute to the induction of apoptosis and disruption of mitochondrial function. In addition, both derivatives exhibited increased expression of Akt and CA IX genes, suggesting activation of the Akt/HIF pathway. However, the exact mechanism and its relations to the observed overexpression of miR-210 need further investigation. The acceptable absorption and distribution properties predicted by ADMET analysis suggest favorable pharmacokinetic properties for these derivatives.

The human acetylcholinesterase C-terminal T30 peptide activates neuronal growth through alpha 7 nicotinic acetylcholine receptors and the mTOR pathway

Acetylcholinesterase (AChE) is a highly conserved enzyme responsible for the regulation of acetylcholine signaling within the brain and periphery. AChE has also been shown to participate in non-enzymatic activity and contribute to cellular development and aging. In particular, enzymatic cleavage of the synaptic AChE isoform, AChE-T, is shown to generate a bioactive T30 peptide that binds to the ⍺7 nicotinic acetylcholine receptor (nAChR) at synapses. Here, we explore intracellular mechanisms of T30 signaling within the human cholinergic neural cell line SH-SY5Y using high performance liquid chromatography (HPLC) coupled to electrospray ionization mass spectrometry (ESI-MS/MS). Proteomic analysis of cells exposed to (100 nM) T30 for 3-days reveals significant changes within proteins important for cell growth. Specifically, bioinformatic analysis identifies proteins that converge onto the mammalian target of rapamycin (mTOR) pathway signaling. Functional experiments confirm that T30 regulates neural cell growth via mTOR signaling and ⍺7 nAChR activation. T30 was found promote mTORC1 pro-growth signaling through an increase in phosphorylated elF4E and S6K1, and a decrease in the autophagy LC3B-II protein. These findings are corroborated in hippocampal neurons and show that T30 promotes dendritic arborization. Taken together, our findings define mTOR as a novel pathway activated by T30 interaction with the nAChR and suggest a role for this process in human disease.

Glaucomatous optic neuropathy: Mitochondrial dynamics, dysfunction and protection in retinal ganglion cells

Glaucoma is a leading cause of irreversible blindness worldwide and is characterized by a slow, progressive, and multifactorial degeneration of retinal ganglion cells (RGCs) and their axons, resulting in vision loss. Despite its high prevalence in individuals 60 years of age and older, the causing factors contributing to glaucoma progression are currently not well characterized. Intraocular pressure (IOP) is the only proven treatable risk factor. However, lowering IOP is insufficient for preventing disease progression. One of the significant interests in glaucoma pathogenesis is understanding the structural and functional impairment of mitochondria in RGCs and their axons and synapses. Glaucomatous risk factors such as IOP elevation, aging, genetic variation, neuroinflammation, neurotrophic factor deprivation, and vascular dysregulation, are potential inducers for mitochondrial dysfunction in glaucoma. Because oxidative phosphorylation stress-mediated mitochondrial dysfunction is associated with structural and functional impairment of mitochondria in glaucomatous RGCs, understanding the underlying mechanisms and relationship between structural and functional alterations in mitochondria would be beneficial to developing mitochondria-related neuroprotection in RGCs and their axons and synapses against glaucomatous neurodegeneration. Here, we review the current studies focusing on mitochondrial dynamics-based structural and functional alterations in the mitochondria of glaucomatous RGCs and therapeutic strategies to protect RGCs against glaucomatous neurodegeneration.

Retinoic Acid Has Neuroprotective effects by Modulating Thioredoxin in Ischemic Brain Damage and Glutamate-exposed Neurons

Ischemic stroke is a neurological disorder that causes pathological changes by increasing oxidative stress. Retinoic acid is one of the metabolites of vitamin A. It regulates oxidative stress and exerts neuroprotective effects. Thioredoxin is a small redox protein with antioxidant activity. The aim of this study was to investigate whether retinoic acid modulates the expression of thioredoxin in ischemic brain injury. Cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) surgery and retinoic acid (5 mg/kg) or vehicle was administered to adult male rats for four days prior to surgery. MCAO induced neurological deficits and increased oxidative stress and retinoic acid attenuated these changes. Retinoic acid ameliorated the MCAO-induced decrease in thioredoxin expression. MCAO decreases the interaction between thioredoxin and apoptosis signal-regulating kinase 1 (ASK1), and retinoic acid treatment alleviates this decrease. Glutamate (5 mM) exposure induced cell death and decreased thioredoxin expression in cultured neurons. Retinoic acid treatment attenuated these changes in a dose-dependent manner. Retinoic acid prevented the decrease of bcl-2 expression and the increase of bax expression caused by glutamate exposure. Moreover, retinoic acid attenuated the increases in caspase-3, cleaved caspase-3, and cytochrome c in glutamate-exposed neurons. However, the mitigation effects of retinoic acid were lower in thioredoxin siRNA-transfected neurons than in non-transfected neurons. These results demonstrate that retinoic acid regulates oxidative stress and thioredoxin expression, maintains the interaction between thioredoxin and ASK1, and modulates apoptosis-associated proteins. Taken together, these results suggest that retinoic acid has neuroprotective effects by regulating thioredoxin expression and modulating apoptotic pathway.

Deciphering the molecular details of interactions between anti-COVID drugs and functional human proteins: in silico approach

The molecular docking calculations have been employed to investigate the interactions a set of proteins with the repurposed anti-COVID drugs. The position of the therapeutic agents within the protein structure was dependent on a particular drug-protein system and varied from the binding cleft to the periphery of the polypeptide chain. Interactions involved in the drug-protein complexation includes predominantly hydrogen bonding and hydrophobic contacts. The obtained results may be of particular importance while developing the anti-COVID strategies as well as for deeper understanding of the drug pharmacodynamics and pharmacokinetics.

In vitro effects of 2-methyl-3-propylbutane-1,4-diol purified from Alstonia boonei on erythrocyte membrane stabilization and mitochondrial membrane permeabilization

A recent review on the ethnomedicinal, chemical, pharmacological, and toxicological properties of Alstonia boonei revealed the plant's potential in the treatment and management of a range of diseases. However, most of these pharmacological effects are only traceable to the crude form of the plant extract and not specific natural products. Phytochemical investigation of the methanol fraction of the methanol extract of the stem-bark of Alstonia boonei led to the isolation and identification of 2-methyl-3-propylbutane-1,4-diol. The structures were elucidated by the application of 1D-, and 2D-NMR spectroscopic analyses and by comparison with literature data. In this study, the membrane stabilizing activity, mitochondrial membrane permeability transition pore opening, cytochrome c release, mitochondrial ATPase activity, and prevention of mitochondrial lipid peroxidation activity of 2-methyl-3-propylbutane-1,4-diol (MPBD) isolated from A. boonei were determined. The results showed that MPBD significantly (p < .05) prevented peroxidation of mitochondrial membrane lipids and hemolysis using both the heat-induced and hypotonic solution-induced membrane stabilization assays. On the contrary, the compound caused large amplitude swelling of rat liver mitochondria in the absence of calcium, significant (p < .05) cytochrome c release and enhancement of mitochondrial ATPase activity in vitro. Our findings suggest that MPBD showed characteristic biological properties useful in modulating cell death.

Effect of prebiotics administered during embryo development on mitochondria in intestinal and immune tissues of adult broiler chickens

Mitochondria are cellular organelles that are the place of many metabolic processes and thus have a significant impact on the proper functioning of the organism. These organelles respond easily to environmental stimuli and cellular energy demands. To ensure the proper functioning of mitochondria, a high supply of specific nutrients is needed. Literature reports suggest that a favorable profile of the intestinal microbiota may improve the functioning of the mitochondria. The gut microbiota transmits a signal to the mitochondria of the mucosa cells. This signaling alters mitochondrial metabolism, activates cells of the immune system, and alters intestinal epithelial barrier functions. The aim of the study is to determine the relative number of mtDNA copies and to analyze the mitochondrial expression of genes related to respiratory chain proteins and energy metabolism in the intestinal mucosa and cecal tonsils of broiler chickens injected on the d 12 of egg incubation with various prebiotics. 300 incubated eggs of Ross 308 broiler chicken on d 12 of incubation were injected with: control group with physiological saline, prebiotics: XOS3, XOS4, MOS3, and MOS4. On d 42 after hatching, 8 individuals from each group were sacrificed. Cecal mucosa and cecal tonsils were collected postmortem for DNA and RNA isolation. Relative mitochondrial DNA copy number analysis was performed by qPCR method using 2 calculation methods. Gene expression analysis of the cecal tonsils and cecal mucosa was performed by RT-qPCR for the gene panel selected based on literature data and gene functions related to mitochondria: CS, EPX (MPO), CYCS, TFAM, NRF1, ND2, MnSOD (SOD2). As the results showed the overall mt DNA copy number is stable in both tissues. The significant change in gene expression in cecal mucosa was induced by XOS4 and MOS3. Both prebiotics caused upregulation of gene expression. In cecal tonsils all prebiotics caused downregulation of entire set of genes under the analysis. Statistically significant results of gene expression were detected for CYCS, ND2, NRF, TFAM for all experimental groups.

Analysis of the Interaction between DNA Aptamers and Cytochrome C on the Surface of Lipid Films and on the MUA Monolayer: A QCM-D Study

We analyzed the possibility of the detection of cytochrome c (cyt c) being physically adsorbed on lipid films or covalently bounded to 11-mercapto-1-undecanoic acid (MUA) chemisorbed on the gold layer using quartz crystal microbalance with dissipation monitoring (QCM-D). The negatively charged lipid film composed of a mixture of zwitterionic DMPC and negatively charged DMPG phospholipids at a molar ratio of 1:1 allowed the formation of a stable cyt c layer. Addition of DNA aptamers specific to cyt c, however, resulted in removal of cyt c from the surface. The interaction of cyt c with the lipid film and its removal by DNA aptamers were accompanied by changes in viscoelastic properties evaluated using the Kelvin-Voigt model. Cyt c covalently bound to MUA also provided a stable protein layer already at its relatively low concentrations (0.5 μM). A decrease in the resonant frequency following the addition of gold nanowires (AuNWs) modified by DNA aptamers was observed. The interaction of aptamers with cyt c on the surface can be a combination of specific and non-specific interactions due to electrostatic forces between negatively charged DNA aptamers and positively charged cyt c.

Triphenylphosphonium conjugated gold nanotriangles impact Pi3K/AKT pathway in breast cancer cells: a photodynamic therapy approach

Although gold nanoparticles based photodynamic therapy (PDT) were reported to improve efficacy and specificity, the impact of surface charge in targeting cancer is still a challenge. Herein, we report gold nanotriangles (AuNTs) tuned with anionic and cationic surface charge conjugating triphenylphosphonium (TPP) targeting breast cancer cells with 5-aminoleuvinic acid (5-ALA) based PDT, in vitro. Optimized surface charge of AuNTs with and without TPP kill breast cancer cells. By combining, 5-ALA and PDT, the surface charge augmented AuNTs deliver improved cellular toxicity as revealed by MTT, fluorescent probes and flow cytometry. Further, the 5-ALA and PDT treatment in the presence of AuNTs impairs cell survival Pi3K/AKT signaling pathway causing mitochondrial dependent apoptosis. The cumulative findings demonstrate that, cationic AuNTs with TPP excel selective targeting of breast cancer cells in the presence of 5-ALA and PDT.

Inhibition of antiapoptotic BCL-2 proteins with ABT-263 induces fibroblast apoptosis, reversing persistent pulmonary fibrosis

Patients with progressive fibrosing interstitial lung diseases (PF-ILDs) carry a poor prognosis and have limited therapeutic options. A hallmark feature is fibroblast resistance to apoptosis, leading to their persistence, accumulation, and excessive deposition of extracellular matrix. A complex balance of the B cell lymphoma 2 (BCL-2) protein family controlling the intrinsic pathway of apoptosis and fibroblast reliance on antiapoptotic proteins has been hypothesized to contribute to this resistant phenotype. Examination of lung tissue from patients with PF-ILD (idiopathic pulmonary fibrosis and silicosis) and mice with PF-ILD (repetitive bleomycin and silicosis) showed increased expression of antiapoptotic BCL-2 family members in α-smooth muscle actin-positive fibroblasts, suggesting that fibroblasts from fibrotic lungs may exhibit increased susceptibility to inhibition of antiapoptotic BCL-2 family members BCL-2, BCL-XL, and BCL-W with the BH3 mimetic ABT-263. We used 2 murine models of PF-ILD to test the efficacy of ABT-263 in reversing established persistent pulmonary fibrosis. Treatment with ABT-263 induced fibroblast apoptosis, decreased fibroblast numbers, and reduced lung collagen levels, radiographic disease, and histologically evident fibrosis. Our studies provide insight into how fibroblasts gain resistance to apoptosis and become sensitive to the therapeutic inhibition of antiapoptotic proteins. By targeting profibrotic fibroblasts, ABT-263 offers a promising therapeutic option for PF-ILDs.

Aggressive-like behaviour and neurocognitive impairment in alcohol herbal mixture-fed mice are associated with increased neuroinflammation and neuronal apoptosis in the prefrontal cortex

Alcohol-induced aggression and related violence is a serious and common social problem globally. Alcohol use is increasingly found in the form of alcoholic herbal mixtures (AHM) with indiscriminate and unregulated alcohol content. This study investigated the effects of AHM on aggressive-like, neurocognitive impairment and brain biochemical alteration in mice. Thirty-two male resident mice were paired housed with female mice for 21 days in four groups (n = 8). Resident mice were treated orally with normal saline, AHM, ethanol and AHM + ethanol daily for 14 days. Aggressive-like behaviour was scored based on the latency and frequency of attacks by the resident mouse on the intruder. Neurocognitive impairment was determined using the Y-maze test (YMT) and novel object recognition test (NORT). Acetylcholinesterase, glutamic acid decarboxylase (GAD), pro-inflammatory and oxidative stress parameters were determined in the prefrontal cortex (PFC). Neuronal morphology, cytochrome c (Cyt-c) and nuclear factor-kappa B (NF-ĸB) expressions were determined. AHM and in combination with ethanol showed an increased index of aggression typified by frequency of attack and reduced latency to attack when compared to normal saline-treated animals. Co-administration of AHM and ethanol significantly reduced cognitive correct alternation (%) and discrimination index in the YMT and NORT, respectively. AHM and ethanol increased acetylcholinesterase, Pro-inflammatory cytokines and oxidative stress parameters while they reduced GAD. There were significantly reduced neuronal counts and increased expression of Cyt-c and NF-ĸB, respectively Alcoholic herbal mixture increased aggressiveness and caused neurocognitive impairment via increased oxido-inflammatory stress in the prefrontal cortex.

Apoptosis promoting activity of selected plant steroid in MRMT-1 breast cancer cell line by modulating mitochondrial permeation pathway

Escape from apoptosis is one of the main demeanor characteristics of cancer cells. Mitochondria are key players in initiating and regulating the intrinsic apoptosis pathway. Hexokinase2 (HK2) is ubiquitously expressed in several cancer cells and is essential for cell survival and death. The binding of HK2 to mitochondria promotes cell proliferation, while AKT-1 mediated pathway is crucial in this process. Peimine, a steroidal alkaloid derived from plant steroids, is screened for docking properties, ADMET properties, and drug-likeness. Apoptosis targets are predicted by network pharmacology using 47 genes associated with apoptosis. According to in silico study, peimine has the potential for dual Targeting on HK2 and AKT1. For further confirmation, peimine was subjected to Cell culture studies using MRMT-1 rat breast cancer cells. The elevated levels of cytochrome c and Caspase 9 activity indicate that the intrinsic apoptosis pathway causes cell death. The decreased glucose uptake by the MRMT-1 cells indicates that pimine inhibits glucose transport by inhibiting the membrane HK2.

Knock-down of YME1L1 induces mitochondrial dysfunction during early porcine embryonic development

YME1L1, a mitochondrial metalloproteinase, is an Adenosine triphosphate (ATP)-dependent metalloproteinase and locates in the mitochondrial inner membrane. The protease domain of YME1L1 is oriented towards the mitochondrial intermembrane space, which modulates the mitochondrial GTPase optic atrophy type 1 (OPA1) processing. However, during embryonic development, there is no report yet about the role of YME1L1 on mitochondrial biogenesis and function in pigs. In the current study, the mRNA level of YME1L1 was knocked down by double strand RNA microinjection to the 1-cell stage embryos. The expression patterns of YME1L1 and its related proteins were performed by immunofluorescence and western blotting. To access the biological function of YME1L1, we first counted the preimplantation development rate, diameter, and total cell number of blastocyst on day-7. First, the localization of endogenous YME1L1 was found in the punctate structures of the mitochondria, and the expression level of YME1L1 is highly expressed from the 4-cell stage. Following significant knock-down of YME1L1, blastocyst rate and quality were decreased, and mitochondrial fragmentation was induced. YME1L1 knockdown induced excessive ROS production, lower mitochondrial membrane potential, and lower ATP levels. The OPA1 cleavage induced by YME1L1 knockdown was prevented by double knock-down of YME1L1 and OMA1. Moreover, cytochrome c, a pro-apoptotic signal, was released from the mitochondria after the knock-down of YME1L1. Taken together, these results indicate that YME1L1 is essential for regulating mitochondrial fission, function, and apoptosis during porcine embryo preimplantation development.

Single-walled carbon nanotube conjugated cytochrome c as exogenous nano catalytic medicine to combat intracellular oxidative stress

Mitochondrial dysfunction has been reported to be one of the main causes of many diseases including cancer, type2 diabetes, neurodegenerative disorders, cardiac ischemia, sepsis, muscular dystrophy, etc. Under in vitro conditions, Cytochrome C (Cyt C) maintains mitochondrial homeostasis and stimulates apoptosis, along with being a key participant in the life-supporting function of ATP synthesis. Hence, the medicinal importance of Cyt C as catalytic defense is immensely important in various mitochondrial disorders. Here, we have developed a nanomaterial via electrostatically conjugating oxidized single-wall carbon nanotube with Cyt C (Cyt C@cSWCNT) for the exogenous delivery of Cyt C. The chemical and morphological characterization of the developed Cyt C@cSWCNT was done using UV-vis, FTIR, XPS, powder XRD, TGA/DSC, TEM, etc. The developed Cyt C@cSWCNT exhibited bifunctional catalase and peroxidase activity with K_m (∼ 642.7 μM and 351.6 μM) and V_max (∼0.33 μM/s and 2.62 μM/s) values, respectively. Also, through this conjugation Cyt C was found to retain its catalytic activity even at 60 °C, excellent catalytic recyclability (at least up to 3 times), and wider pH activity (pH = 3 to 9). Cyt C@cSWCNT was found to promote intracellular ROS quenching and maintain mitochondrial membrane potential and cellular membrane integrity via Na⁺/K⁺ ion homeostasis during the H₂O₂ stress. Overall the present strategy provides an alternative approach for the exogenous delivery of Cyt C which can be used as nano catalytic medicine.

Established and emerging roles for mitochondria in neutrophils

Neutrophils are the most abundant innate immune cells in human blood, emerging as important players in a variety of diseases. Mitochondria are bioenergetic, biosynthetic, and signaling organelles critical for cell fate and function. Mitochondria have been overlooked in neutrophil research owing to the conventional view that neutrophils contain few, if any, competent mitochondria and do not rely on these organelles for adenosine triphosphate production. A growing body of evidence suggests that mitochondria participate in neutrophil biology at many levels, ranging from neutrophil development to chemotaxis, effector function, and cell death. Moreover, mitochondria and mitochondrial components, such as mitochondrial deoxyribonucleic acid, can be released by neutrophils to eliminate infection and/or shape immune response, depending on the specific context. In this review, we provide an update on the functional role of mitochondria in neutrophils, highlight mitochondria as key players in modulating the neutrophil phenotype and function during infection and inflammation, and discuss the possibilities and challenges to exploit the unique aspects of mitochondria in neutrophils for disease treatment.

Rubus Capped Zinc Oxide Nanoparticles Induce Apoptosis in MCF-7 Breast Cancer Cells

Rubus fairholmianus (RF) has widely been used to treat various ailments, including pain, diabetes, and cancer. Zinc oxide nanoparticles (ZnO NPs) have drawn attention in modern healthcare applications. Hence, we designed this study to synthesize zinc oxide (ZnO) nanoparticles using R. fairholmianus root extract to investigate its synergistic cytotoxic effect on MCF-7 cells and explore the possible cell death mechanism. ZnO NPs were synthesized via green synthesis using R. fairholmianus root extract, and the effect on MCF-7 cells was determined by looking at cellular morphology, proliferation, cytotoxicity, apoptosis, and reactive oxygen species (ROS). The results showed that cellular proliferation was reduced following treatment with R. fairholmianus capped zinc oxide nanoparticles (RFZnO NPs), while cytotoxicity and ROS were increased. There was also an increase in apoptosis as indicated by the significant increase in cytoplasmic cytochrome c and caspase 3/7 (markers of apoptosis), as well as increased levels of pro-apoptotic proteins (p53, Bax) and decreased levels of anti-apoptotic protein (Bcl-2). In conclusion, these results showed that RFZnO NPs induce apoptosis in breast cancer cells via a mitochondria-mediated caspase-dependent apoptotic pathway and suggest the use of acetone root extract of R. fairholmianus for the treatment of cancer-related ailments.

Enzalutamide Induces Apoptotic Insults to Human Drug-Resistant and -Sensitive Glioblastoma Cells via an Intrinsic Bax-Mitochondrion-Cytochrome C Caspase Cascade Activation Pathway

Glioblastoma multiforme (GBM) is the most common and malignant brain tumor. Temozolomide (TMZ) is the first-line chemotherapeutic drug for treating GBM. However, drug resistance is still a challenging issue in GBM therapy. Our preliminary results showed upregulation of androgen receptor (AR) gene expression in human GBM tissues. This study was designed to evaluate the effects of enzalutamide, a specific inhibitor of the AR, on killing drug-resistant and -sensitive glioblastoma cells and the possible mechanisms. Data mining from The Cancer Genome Atlas (TCGA) database revealed upregulation of AR messenger (m)RNA and protein expressions in human GBM tissues, especially in male patients, compared to normal human brains. In addition, expressions of AR mRNA and protein in human TMZ-sensitive U87 MG and -resistant U87 MG-R glioblastoma cells were elevated compared to normal human astrocytes. Exposure of human U87 MG and U87 MG-R cells to enzalutamide concentration- and time-dependently decreased cell viability. As to the mechanism, enzalutamide killed these two types of glioblastoma cells via an apoptotic mechanism. Specifically, exposure to enzalutamide augmented enzyme activities of caspase-9 rather than those of caspase-8. Moreover, enzalutamide successively triggered an elevation in levels of the proapoptotic Bax protein, a reduction in the mitochondrial membrane potential, release of cytochrome c, cascade activation of caspases-3 and -6, DNA fragmentation, and cell apoptosis in human TMZ-sensitive and -resistant glioblastoma cells. Pretreatment with Z-VEID-FMK, an inhibitor of caspase-6, caused significant attenuations in enzalutamide-induced morphological shrinkage, DNA damage, and apoptotic death. Taken together, this study showed that enzalutamide could significantly induce apoptotic insults to human drug-resistant and -sensitive glioblastoma cells via an intrinsic Bax-mitochondrion-cytochrome c-caspase cascade activation pathway. Enzalutamide has the potential to be a drug candidate for treating GBM by targeting the AR signaling axis.

NSP4 and ORF9b of SARS-CoV-2 Induce Pro-Inflammatory Mitochondrial DNA Release in Inner Membrane-Derived Vesicles

Circulating cell-free mitochondrial DNA (cf-mtDNA) has been found in the plasma of severely ill COVID-19 patients and is now known as a strong predictor of mortality. However, the underlying mechanism of mtDNA release is unexplored. Here, we show a novel mechanism of SARS-CoV-2-mediated pro-inflammatory/pro-apoptotic mtDNA release and a rational therapeutic stem cell-based approach to mitigate these effects. We systematically screened the effects of 29 SARS-CoV-2 proteins on mitochondrial damage and cell death and found that NSP4 and ORF9b caused extensive mitochondrial structural changes, outer membrane macropore formation, and the release of inner membrane vesicles loaded with mtDNA. The macropore-forming ability of NSP4 was mediated through its interaction with BCL2 antagonist/killer (BAK), whereas ORF9b was found to inhibit the anti-apoptotic member of the BCL2 family protein myeloid cell leukemia-1 (MCL1) and induce inner membrane vesicle formation containing mtDNA. Knockdown of BAK and/or overexpression of MCL1 significantly reversed SARS-CoV-2-mediated mitochondrial damage. Therapeutically, we engineered human mesenchymal stem cells (MSCs) with a simultaneous knockdown of BAK and overexpression of MCL1 (MSCshBAK+MCL1) and named these cells IMAT-MSCs (intercellular mitochondrial transfer-assisted therapeutic MSCs). Upon co-culture with SARS-CoV-2-infected or NSP4/ORF9b-transduced airway epithelial cells, IMAT-MSCs displayed functional intercellular mitochondrial transfer (IMT) via tunneling nanotubes (TNTs). The mitochondrial donation by IMAT-MSCs attenuated the pro-inflammatory and pro-apoptotic mtDNA release from co-cultured epithelial cells. Our findings thus provide a new mechanistic basis for SARS-CoV-2-induced cell death and a novel therapeutic approach to engineering MSCs for the treatment of COVID-19.

Assessing the Functional and Structural Stability of the Met80Ala Mutant of Cytochrome c in Dimethylsulfoxide

The Met80Ala variant of yeast cytochrome c is known to possess electrocatalytic properties that are absent in the wild type form and that make it a promising candidate for biocatalysis and biosensing. The versatility of an enzyme is enhanced by the stability in mixed aqueous/organic solvents that would allow poorly water-soluble substrates to be targeted. In this work, we have evaluated the effect of dimethylsulfoxide (DMSO) on the functionality of the Met80Ala cytochrome c mutant, by investigating the thermodynamics and kinetics of electron transfer in mixed water/DMSO solutions up to 50% DMSO v/v. In parallel, we have monitored spectroscopically the retention of the main structural features in the same medium, focusing on both the overall protein structure and the heme center. We found that the organic solvent exerts only minor effects on the redox and structural properties of the mutant mostly as a result of the modification of the dielectric constant of the solvent. This would warrant proper functionality of this variant also under these potentially hostile experimental conditions, that differ from the physiological milieu of cytochrome c.

Effects of dietary supplementation with selenium yeast and jujube powder on mitochondrial oxidative damage and apoptosis of chicken

The main objective of this study was to explore the effects of dietary selenium yeast and jujube powder on mitochondrial oxidative damage and cell apoptosis of broilers during postmortem aging, chicken breasts of broilers fed diets supplemented with different concentrations of selenium yeast and jujube powder were used as research subjects. With the prolongation of postmortem aging time, the levels of reactive oxygen species (ROS), carbonyl content, mitochondrial permeability transition pore (MPTP) openness, and mitochondrial membrane permeability increased significantly (P < 0.05). The contents of the sulfhydryl, mitochondrial membrane potential, shear force, and cytochrome C (Cyt-c) reduction level decreased significantly (P < 0.05). The activity of Caspase-3 and Caspase-9 increased from 0 to 24 h postmortem but fell from 24 to 72 h postmortem. Compared with the control group, dietary selenium yeast and jujube powder significantly reduced mitochondrial oxidative damage. They greatly increased the shear force, mitochondrial membrane potential, and Cyt-c reduction levels (P < 0.05). Among them, the combination group of high-dose selenium yeast and jujube powder had more significant effects on ROS scavenging, reducing cell membrane permeability, protecting cell membrane integrity, and increasing Cyt-c reduction level (P < 0.05). In conclusion, cell apoptosis intensifies during the chicken breast's aging time, and muscle tenderness continues. Still, different doses of dietary selenium yeast and jujube powder can inhibit mitochondrial oxidation to various degrees. The combined group of selenium yeast and jujube powder with 0.6 mg·kg⁻¹ has the best effect. This study is of great significance for applying natural antioxidant ingredients such as selenium yeast and jujube powder in the development and utilization of poultry feed.

Recent Advances Regarding the Molecular Mechanisms of Triterpenic Acids: A Review (Part I)

Triterpenic acids are phytocompounds with a widespread range of biological activities that have been the subject of numerous in vitro and in vivo studies. However, their underlying mechanisms of action in various pathologies are not completely elucidated. The current review aims to summarize the most recent literature, published in the last five years, regarding the mechanism of action of three triterpenic acids (asiatic acid, oleanolic acid, and ursolic acid), corelated with different biological activities such as anticancer, anti-inflammatory, antidiabetic, cardioprotective, neuroprotective, hepatoprotective, and antimicrobial. All three discussed compounds share several mechanisms of action, such as the targeted modulation of the PI3K/AKT, Nrf2, NF-kB, EMT, and JAK/STAT3 signaling pathways, while other mechanisms that proved to only be specific for a part of the triterpenic acids discussed, such as the modulation of Notch, Hippo, and MALAT1/miR-206/PTGS1 signaling pathway, were highlighted as well. This paper stands as the first part in our literature study on the topic, which will be followed by a second part focusing on other triterpenic acids of therapeutic value.

Programmed cell death detection methods: a systematic review and a categorical comparison

Programmed cell death is considered a key player in a variety of cellular processes that helps to regulate tissue growth, embryogenesis, cell turnover, immune response, and other biological processes. Among different types of cell death, apoptosis has been studied widely, especially in the field of cancer research to understand and analyse cellular mechanisms, and signaling pathways that control cell cycle arrest. Hallmarks of different types of cell death have been identified by following the patterns and events through microscopy. Identified biomarkers have also supported drug development to induce cell death in cancerous cells. There are various serological and microscopic techniques with advantages and limitations, that are available and are being utilized to detect and study the mechanism of cell death. The complexity of the mechanism and difficulties in distinguishing among different types of programmed cell death make it challenging to carry out the interventions and delay its progression. In this review, mechanisms of different forms of programmed cell death along with their conventional and unconventional methods of detection of have been critically reviewed systematically and categorized on the basis of morphological hallmarks and biomarkers to understand the principle, mechanism, application, advantages and disadvantages of each method. Furthermore, a very comprehensive comparative analysis has been drawn to highlight the most efficient and effective methods of detection of programmed cell death, helping researchers to make a reliable and prudent selection among the available methods of cell death assay. Conclusively, how programmed cell death detection methods can be improved and can provide information about distinctive stages of cell death detection have been discussed.

Quercetin Mitigates Cisplatin-Induced Oxidative Damage and Apoptosis in Cardiomyocytes through Nrf2/HO-1 Signaling Pathway

Cisplatin is massively used to treat solid tumors. However, several severe adverse effects, such as cardiotoxicity, are obstacles to its clinical application. Cardiotoxicity may lead to congestive heart failure and even sudden cardiac death in patients receiving cisplatin. Therefore, finding a novel therapeutic strategy for the prevention of cisplatin-induced cardiotoxicity is urgent. Quercetin is a flavonol compound that can be found in dietary fruits and vegetables. The antioxidant function and anti-inflammatory capacity of quercetin have been reported. However, whether quercetin could protect against cisplatin-caused apoptosis and cellular damage in cardiomyocytes is still unclear. H9c2 cardiomyocytes were treated with cisplatin (40 μM) for 24 h to induce cellular damage with or without quercetin pretreatment. We found that quercetin activates Nrf2 and HO-1 expression, thereby mitigating cisplatin-caused cytotoxicity in H9c2 cells. Quercetin also increases SOD levels, maintains mitochondrial function, and reduces oxidative stress under cisplatin stimulation. Quercetin attenuates cisplatin-induced apoptosis and inflammation in H9c2 cardiomyocytes; however, these cytoprotective effects were diminished by silencing Nrf2 and HO-1. In conclusion, this study reports that quercetin has the potential to antagonize cisplatin-caused cardiotoxicity by reducing ROS-mediated mitochondrial damage and inflammation via the Nrf2/HO-1 and p38MAPK/NF-[Formula: see text]Bp65/IL-8 signaling pathway. This study provided the theoretical basis and experimental proof for the clinical application of quercetin as a new effective strategy to relieve chemotherapy-induced cardiotoxicity.

A Single-Cell Raman Spectroscopy Analysis of Bone Marrow Mesenchymal Stem/Stromal Cells to Identify Inter-Individual Diversity

The heterogeneity of stem cells represents the main challenge in regenerative medicine development. This issue is particularly pronounced when it comes to the use of primary mesenchymal stem/stromal cells (MSCs) due to a lack of identification markers. Considering the need for additional approaches in MSCs characterization, we applied Raman spectroscopy to investigate inter-individual differences between bone marrow MSCs (BM-MSCs). Based on standard biological tests, BM-MSCs of analyzed donors fulfill all conditions for their characterization, while no donor-related specifics were observed in terms of BM-MSCs morphology, phenotype, multilineage differentiation potential, colony-forming capacity, expression of pluripotency-associated markers or proliferative capacity. However, examination of BM-MSCs at a single-cell level by Raman spectroscopy revealed that despite similar biochemical background, fine differences in the Raman spectra of BM-MSCs of each donor can be detected. After extensive principal component analysis (PCA) of Raman spectra, our study revealed the possibility of this method to diversify BM-MSCs populations, whereby the grouping of cell populations was most prominent when cell populations were analyzed in pairs. These results indicate that Raman spectroscopy, as a label-free assay, could have a huge potential in understanding stem cell heterogeneity and sorting cell populations with a similar biochemical background that can be significant for the development of personalized therapy approaches.