Trends in oxidative aging theories

Coenzyme Q10 in atherosclerosis

Atherosclerotic disease is a chronic disease that predominantly affects the elderly and is the most common cause of cardiovascular death worldwide. Atherosclerosis is closely related to processes such as abnormal lipid transport and metabolism, impaired endothelial function, inflammation, and oxidative stress. Coenzyme Q10 (CoQ10) is a key component of complex Ⅰ in the electron transport chain and an important endogenous antioxidant that may play a role in decelerating the progression of atherosclerosis. Here, the different forms of CoQ10 presence in the electron transport chain are reviewed, as well as its physiological role in regulating processes such as oxidative stress, inflammatory response, lipid metabolism and cellular autophagy. It was also found that CoQ10 plays beneficial effects in atherosclerosis by mitigating lipid transportation, endothelial inflammation, metabolic abnormalities, and thrombotic processes from the perspectives of molecular mechanisms, animal experiments, and clinical evidence. Besides, the combined use of CoQ10 with other drugs has better synergistic therapeutic effects. It seems reasonable to suggest that CoQ10 could be used in the treatment of atherosclerotic cardiovascular diseases while more basic and clinical studies are needed.

Anti-aging effect of peptides on Caenorhabditis elegans: a meta-analysis

BACKGROUND

Recently, peptides have been studied in Caenorhabditis elegans for anti-aging research. Due to the lack of sufficient evidence, we conducted this meta-analysis focusing on the anti-aging effect of peptides in C. elegans to provide more convincing evidence.

RESULTS

A literature search in PubMed, SCOUPUS, and Web of Science databases yielded 2879 articles. After removing duplicates and based on inclusion criteria and STAIR checklist quality assessment, nine articles were selected. Data extraction and analysis showed that, compared to the control group without peptide intervention, peptide supplementation significantly reduced nematode mortality risk [hazard ratio = 0.54, 95% confidence interval (CI) = 0.47, 0.62; P < 0.05], significantly increased the pharyngeal pumping rate [standardized mean difference (SMD) = 1.64, 95% CI = 0.87, 2.41; P < 0.05], bending frequency (SMD = 1.67, 95% CI = 1.16, 2.18; P < 0.05), and significantly decreased the accumulation of lipofuscin levels within nematodes (SMD = -4.48, 95% CI = -6.85, -2.12; P < 0.05). Additionally, subgroup analysis showed that doses ranging from 0.1 to 1 mg/mL (HR = 0.50, 95% CI = 0.38, 0.65; P < 0.05) displayed better anti-aging effects compared to other dose ranges.

CONCLUSION

The findings suggest that peptides can significantly extend the lifespan of C. elegans under normal circumstances and improve three indicators of healthy life. More importantly, subgroup analysis revealed that a dosage of 0.1-1 mg/mL demonstrated superior anti-aging effects. This meta-analysis provides more convincing evidence that peptides can play an anti-aging role in C. elegans. © 2024 Society of Chemical Industry.

Stress granule-mediated RNA regulatory mechanism in Alzheimer's disease

Living organisms experience a range of stresses. To cope effectively with these stresses, eukaryotic cells have evolved a sophisticated mechanism involving the formation of stress granules (SGs), which play a crucial role in protecting various types of RNA species under stress, such as mRNAs and long non-coding RNAs (lncRNAs). SGs are non-membranous cytoplasmic ribonucleoprotein (RNP) granules, and the RNAs they contain are translationally stalled. Importantly, SGs have been thought to contribute to the pathophysiology of neurodegenerative diseases, including Alzheimer's disease (AD). SGs also contain multiple RNA-binding proteins (RBPs), several of which have been implicated in AD progression. SGs are transient structures that dissipate after stress relief. However, the chronic stresses associated with aging lead to the persistent formation of SGs and subsequently to solid-like pathological SGs, which could impair cellular RNA metabolism and also act as a nidus for the aberrant aggregation of AD-associated proteins. In this paper, we provide a comprehensive summary of the physical basis of SG-enriched RNAs and SG-resident RBPs. We then review the characteristics of AD-associated gene transcripts and their similarity to the SG-enriched RNAs. Furthermore, we summarize and discuss the functional implications of SGs in neuronal RNA metabolism and the aberrant aggregation of AD-associated proteins mediated by SG-resident RBPs in the context of AD pathogenesis. Geriatr Gerontol Int 2024; 24: 7-14.

Chronological and reproductive aging-associated changes in resistance to oxidative stress in post-reproductive female mice

Effort toward reproduction is often thought to negatively influence health and survival. Reproduction has been shown to influence metabolism, but the pathways and mechanisms have yet to be thoroughly elucidated. In the current experiments, our aim was to dissect the role of young and old ovarian tissues in the response to oxidative stress, through changes in liver oxidative stress response proteins. Liver proteins were analyzed in control mice at 4, 13, and 27 months of age and compared to 23-month-old mice which received young ovarian tissue transplants (intact or follicle-depleted) at 13 months of age. In control mice, of the 29 oxidative stress response proteins measured, 31% of the proteins decreased, 52% increased, and 17% were unchanged from 13 to 27 months. The greatest changes were seen during the period of reproductive failure, from 4 to 13 months of age. In transplanted mice, far more proteins were decreased from 13 to 23 months (93% in follicle-containing young ovary recipients; 62% in follicle-depleted young ovary recipients). Neither transplant group reflected changes seen in control mice between 13 and 27 months. Estradiol levels in transplant recipient mice were not increased compared with age-matched control mice. The current results suggest the presence of a germ cell- and estradiol-independent ovarian influence on aging-associated changes in the response to oxidative stress, which is manifest differently in reproductive-aged adults and post-reproductive-aged mice. The results presented here separate chronological and ovarian aging and the influence of estradiol in the response to aging-associated oxidative stress and support a novel, estradiol-independent role for the ovary in female health and survival.

Survival, growth and digestive functions after exposure to nanodiamonds - Transgenerational effects beyond contact time in house cricket strains

The long-term exposure effects of nanodiamonds (NDs), spanning an organism's entire lifespan and continuing for subsequent generation, remain understudied. Most research has focused on evaluating their biological impacts on cell lines and selected organisms, typically over short exposure durations lasting hours or days. The study aimed to assess growth, mortality, and digestive functions in wild (H) and long-lived (D) strains of Acheta domesticus (Insecta: Orthoptera) after two-generational exposure to NDs in concentrations of 0.2 or 2 mg kg-1 of food, followed by their elimination in the third generation. NDs induced subtle stimulating effect that depended on the strain and generation. In the first generation, more such responses occurred in the H than in the D strain. In the first generation of H strain insects, contact with NDs increased survival, stimulated the growth of young larvae, and the activity of most digestive enzymes in mature adults. The same doses and exposure time did not cause similar effects in the D strain. In the first generation of D strain insects, survival and growth were unaffected by NDs, whereas, in the second generation, significant stimulation of those parameters was visible. Selection towards longevity appears to support higher resistance of the insects to exposure to additional stressor, at least in the first generation. The cessation of ND exposure in the third generation caused potentially harmful changes, which included, e.g., decreased survival probability in H strain insects, slowed growth of both strains, as well as changes in heterochromatin density and distribution in nuclei of the gut cells in both strains. Such a reaction may suggest the involvement of epigenetic inheritance mechanisms, which may become inadequate after the stress factor is removed.

Melatonin-Mediated Suppression of mtROS-JNK-FOXO1 Pathway Alleviates Hypoxia-Induced Apoptosis in Porcine Granulosa Cells

Numerous studies have established that the hypoxic conditions within ovarian follicles induce apoptosis in granulosa cells (GCs), a pivotal hallmark of follicular atresia. Melatonin (N-acetyl-5-methoxytryptamine, MT), a versatile antioxidant naturally present in follicular fluid, acts as a safeguard for maintaining GCs' survival during stress exposure. In this study, we unveil an innovative protective mechanism of melatonin against hypoxia-triggered GC apoptosis by selectively inhibiting mitochondrial ROS (mtROS) generation. Specifically, under hypoxic conditions, a gradual accumulation of mitochondrial ROS occurred, consequently activating the JNK-FOXO1 pathway, and driving GCs toward apoptosis. The blocking of JNK or FOXO1 diminished hypoxia-induced GC apoptosis, but this effect was nullified in the presence of GSH, indicating that mtROS instigates apoptosis through the JNK-FOXO1 pathway. Consistent with this, hypoxic GCs treated with melatonin exhibited decreased levels of mtROS, reduced JNK-FOXO1 activation, and mitigated apoptosis. However, the protective capabilities of melatonin were attenuated upon inhibiting its receptor MTNR1B, accompanied by the decreased expression of antioxidant genes. Notably, SOD2, a key mitochondrial antioxidant gene modulated by the melatonin-MTNR1B axis, effectively inhibited the activation of mtROS-JNK-FOXO1 and subsequent apoptosis, whereas SOD2 knockdown abrogated the protective role of melatonin in hypoxic GCs. In conclusion, our study elucidates that melatonin, through MTNR1B activation, fosters SOD2 expression, effectively quelling mtROS-JNK-FOXO1-mediated apoptosis in follicular GCs under hypoxic stress.

Impact of air pollution on cardiovascular aging

The world population is aging rapidly, and by some estimates, the number of people older than 60 will double in the next 30 years. With the increase in life expectancy, adverse effects of environmental exposures start playing a more prominent role in human health. Air pollution is now widely considered the most detrimental of all environmental risk factors, with some studies estimating that almost 20% of all deaths globally could be attributed to poor air quality. Cardiovascular diseases are the leading cause of death worldwide and will continue to account for the most significant percentage of non-communicable disease burden. Cardiovascular aging with defined pathomechanisms is a major trigger of cardiovascular disease in old age. Effects of environmental risk factors on cardiovascular aging should be considered in order to increase the health span and reduce the burden of cardiovascular disease in older populations. In this review, we explore the effects of air pollution on cardiovascular aging, from the molecular mechanisms to cardiovascular manifestations of aging and, finally, the age-related cardiovascular outcomes. We also explore the distinction between the effects of air pollution on healthy aging and disease progression. Future efforts should focus on extending the health span rather than the lifespan.

Changes in the Mitochondria in the Aging Process-Can α-Tocopherol Affect Them?

Aerobic organisms use molecular oxygen in several reactions, including those in which the oxidation of substrate molecules is coupled to oxygen reduction to produce large amounts of metabolic energy. The utilization of oxygen is associated with the production of ROS, which can damage biological macromolecules but also act as signaling molecules, regulating numerous cellular processes. Mitochondria are the cellular sites where most of the metabolic energy is produced and perform numerous physiological functions by acting as regulatory hubs of cellular metabolism. They retain the remnants of their bacterial ancestors, including an independent genome that encodes part of their protein equipment; they have an accurate quality control system; and control of cellular functions also depends on communication with the nucleus. During aging, mitochondria can undergo dysfunctions, some of which are mediated by ROS. In this review, after a description of how aging affects the mitochondrial quality and quality control system and the involvement of mitochondria in inflammation, we report information on how vitamin E, the main fat-soluble antioxidant, can protect mitochondria from age-related changes. The information in this regard is scarce and limited to some tissues and some aspects of mitochondrial alterations in aging. Improving knowledge of the effects of vitamin E on aging is essential to defining an optimal strategy for healthy aging.

Chronic inflammation and the hallmarks of aging

BACKGROUND

Recently, the hallmarks of aging were updated to include dysbiosis, disabled macroautophagy, and chronic inflammation. In particular, the low-grade chronic inflammation during aging, without overt infection, is defined as "inflammaging," which is associated with increased morbidity and mortality in the aging population. Emerging evidence suggests a bidirectional and cyclical relationship between chronic inflammation and the development of age-related conditions, such as cardiovascular diseases, neurodegeneration, cancer, and frailty. How the crosstalk between chronic inflammation and other hallmarks of aging underlies biological mechanisms of aging and age-related disease is thus of particular interest to the current geroscience research.

SCOPE OF REVIEW

This review integrates the cellular and molecular mechanisms of age-associated chronic inflammation with the other eleven hallmarks of aging. Extra discussion is dedicated to the hallmark of "altered nutrient sensing," given the scope of Molecular Metabolism. The deregulation of hallmark processes during aging disrupts the delicate balance between pro-inflammatory and anti-inflammatory signaling, leading to a persistent inflammatory state. The resultant chronic inflammation, in turn, further aggravates the dysfunction of each hallmark, thereby driving the progression of aging and age-related diseases.

MAIN CONCLUSIONS

The crosstalk between chronic inflammation and other hallmarks of aging results in a vicious cycle that exacerbates the decline in cellular functions and promotes aging. Understanding this complex interplay will provide new insights into the mechanisms of aging and the development of potential anti-aging interventions. Given their interconnectedness and ability to accentuate the primary elements of aging, drivers of chronic inflammation may be an ideal target with high translational potential to address the pathological conditions associated with aging.

Flavonoid glycoside fraction of Ginkgo biloba extract modulates antioxidants imbalance in vanadium-induced brain damage

Human and animal diseases have always been reported to be treated by medicinal herbs owing to their constituents. Excess sodium metavanadate is a potential environmental toxin when consumed and could induce oxidative damage leading to various neurological disorders and Parkinsons-like diseases. This study is designed to investigate the impact of the flavonoid Glycoside Fraction of Ginkgo Biloba Extract (GBE) (at 30 mg/kg body weight) on vanadium-treated rats. Animals were divided randomly into four groups: Control (Ctrl, normal saline), Ginkgo Biloba (GIBI, 30mg/kg BWT), Vanadium (VANA, 10 mg/kg BWT) and Vanadium + Ginkgo biloba (VANA + GIBI). Markers of oxidative stress (Glutathione Peroxidase and Catalase) were assessed and found to be statistically increased with GIBI when compared with CTRL and treatment groups. Results from routine staining revealed that the control and GIBI group had a normal distribution of cells and a pronounced increase in cell count respectively compared to the VANA group. When compared to the VANA group, the NeuN photomicrographs revealed that the levels of GIBI were within the normal range (***p < 0.001; ** p < 001). The treatment with GIBI showed a better response by increasing the neuronal cells in the VANA+GIBI when compared with the VANA group. The NLRP3 Inflammasome photomicrographs denoted that there was a decrease in NLRP3-positive cells in the control and GIBI groups. The treatment group shows fewer cells compared to that of the VANA group. The treatment group shows fewer cells compared to that of the VANA group. The findings of the study confirmed that ginkgo biloba extract via its flavonoid glycoside fraction has favorable impacts in modulating vanadium-induced brain damage with the potential ability to lower antioxidant levels and reduce neuroinflammation.

Angelica sinensis polysaccharide extends lifespan and ameliorates aging-related diseases via insulin and TOR signaling pathways, and antioxidant ability in Drosophila

Angelica sinensis polysaccharide (ASP) is one of the principal active components of Angelica sinensis (AS) that is widely used in natural medicine and has various pharmacological activities, including antioxidant, anti-inflammatory, and enhancing immunity. However, its pharmacological role of anti-aging needs to be clarified. Here, we detected the beneficial effect and mechanism of ASP on healthy aging and aging-related diseases using the Drosophila melanogaster model. The results showed that oral administration of ASP remarkably extended lifespan, increased reproduction, improved climbing ability, and increased resistance to starvation and oxidative stress in aged flies, mainly via inhibiting insulin signaling (IIS) and TOR signaling and boosting antioxidant ability. Further, ASP supplementation protected against aging-induced intestinal homeostasis imbalance via inhibiting intestinal stem cells (ISCs) hyperproliferation and oxidative damage, improved sleep disorders via rescuing sleep rhythm in aged flies, and had a neuroprotective effect on Aβ42 transgenic flies. Taken together, our findings shed light on the possibility that ASP could increase lifespan, improve healthy aging, and ultimately reduce the incidence of age-related illnesses. It holds promise as a candidate for anti-aging intervention and treatment for aging-associated disorders.

The analyse of the antioxidant effect of natural peloidotherapy in aging process

Medical research has developed remarkably in recent years, including the involvement of the glutathione peroxidase (GPx) family of enzymes in the course of human aging, with numerous clinical studies published in the literature reporting this particular fact. Thus, mud therapy and its effect on biological aging have been represented in papers that have been published to date. Papers published in the literature analyzing GPx vari-ation during sapropelic mud therapy suggest the beneficial effect of this family of en-zymes in diseases with an important inflammatory component, mainly monitored in patients with osteoarthritis. This study investigated the effects of sapropelic mud treat-ment on GPx values in patients receiving treatment with sapropelic mud at the Balneal and Rehabilitation Sanatorium of Techirghiol, Romania. We included 52 patients, split into two groups, who received treatment with cold mud baths and warm mud baths. Values close to statistical significance were found in patients who received treatment with cold mud baths in terms of mean GPx values at the four-time points studied. Fur-ther studies evaluating GPx in patients receiving sapropelic mud treatment are needed.

Nutritional deficiencies that may predispose to long COVID

Multiple nutritional deficiencies (MND) confound studies designed to assess the role of a single nutrient in contributing to the initiation and progression of disease states. Despite the perception of many healthcare practitioners, up to 25% of Americans are deficient in five-or-more essential nutrients. Stress associated with the COVID-19 pandemic further increases the prevalence of deficiency states. Viral infections compete for crucial nutrients with immune cells. Viral replication and proliferation of immunocompetent cells critical to the host response require these essential nutrients, including zinc. Clinical studies have linked levels of more than 22 different dietary components to the likelihood of COVID-19 infection and the severity of the disease. People at higher risk of infection due to MND are also more likely to have long-term sequelae, known as Long COVID.

High Fischer ratio peptide of hemp seed: Preparation and anti-fatigue evaluation in vivo and in vitro

The high Fischer (F) ratio hemp peptide (HFHP) was prepared by enrichment using activated carbon adsorption, ultrafiltration, and Sephadex G-25 gel filtration chromatography. The OD₂₂₀/OD₂₈₀ ratio reached 47.1 with a molecular weight distribution from 180 to 980 Da, a peptide yield up to 21.7 %, and the F value was 31.5. HFHP had high scavenging ability of DPPH, hydroxyl free radicals, and superoxide. Mice experiments showed that the HFHP increased the activity of superoxide dismutase and glutathione peroxidase. The HFHP had no effect on the body weight of mice, but prolonged their weight-bearing swimming time. The lactic acid, serum urea nitrogen, and malondialdehyde of the mice after swimming was reduced, and the liver glycogen increased. The correlation analysis indicated that the HFHP had significant anti-oxidation and anti-fatigue properties.

Naringin protects mice from D-galactose-induced lung aging and mitochondrial dysfunction: Implication of SIRT1 pathways

AIM

Aging is the leading risk factor for diminishing lung function, as well as injury and lung disorder. The target of our research was to examine the potential protective effect of naringin and the possible role of SIRT1 in mice with D-galactose-induced lung aging, by evaluating its effects on antioxidant systems, mitochondrial biogenesis, autophagy, and apoptosis, by referring to the potential involvement of Nrf2/NQO1, LKB1/AMPK/PGC-1α, FOXO1, and P53/caspase-3 signaling.

MATERIAL AND METHODS

The mice were randomly sorted into 5 groups (10 each): 1st^: normal group received subcutaneous normal saline and intragastric distilled water, 2nd^: naringin 300 mg/kg orally, 3rd^: D-galactose (200 mg/kg/day) was administered subcutaneously into mice for eight weeks, to accelerate aging, 4th & 5th: oral naringin (150, 300 mg/kg) was given daily concurrently with D-galactose injection for 8 weeks.

KEY FINDING

In silico investigation revealed that naringin substantially stimulates the SIRT1 and AMPK molecules. At the molecular level, our findings indicated that treatment with naringin stimulated the mitochondrial biogenesis pathway through regulation of the LKB1/AMPK/PGC-1α signals and upregulated FOXO1-mediated autophagy. Furthermore, naringin exhibited antioxidant properties by activating the Nrf2/NQO1 pathway and inhibiting MDA and AGEs levels. In addition, Naringin ameliorated alveolar spaces destruction and bronchial wall thickening, as well as alleviated P53/caspase-3 apoptosis signaling.

SIGNIFICANCE

Naringin exerts protective effects against D-galactose-induced lung aging and enhances longevity by activating SIRT1. SIRT1 regulates various aging-related molecular pathways via restoring pro-oxidant/antioxidant homeostasis, activation of mitochondrial biogenesis, modulating of autophagy and inhibition of apoptosis.

Ageing, Metabolic Dysfunction, and the Therapeutic Role of Antioxidants

The gradual ageing of the world population has been accompanied by a dramatic increase in the prevalence of obesity and metabolic diseases, especially type 2 diabetes. The adipose tissue dysfunction associated with ageing and obesity shares many common physiological features, including increased oxidative stress and inflammation. Understanding the mechanisms responsible for adipose tissue dysfunction in obesity may help elucidate the processes that contribute to the metabolic disturbances that occur with ageing. This, in turn, may help identify therapeutic targets for the treatment of obesity and age-related metabolic disorders. Because oxidative stress plays a critical role in these pathological processes, antioxidant dietary interventions could be of therapeutic value for the prevention and/or treatment of age-related diseases and obesity and their complications. In this chapter, we review the molecular and cellular mechanisms by which obesity predisposes individuals to accelerated ageing. Additionally, we critically review the potential of antioxidant dietary interventions to counteract obesity and ageing.

The antihyperglycemic effect of pulsed electric field-extracted polysaccharide of Kaempferia elegans officinale on streptozotocin induced diabetic mice

Kaempferia elegans polysaccharide (KEP) was extracted using a high-voltage pulsed electric field-assisted hot water method. Its physicochemical properties, in vitro activity and hypoglycemic effect was investigated. Experiments were undertaken with diabetic mice models and the potential mechanism of KEP to improve blood glucose levels was unveiled through measurements of relevant indicators in the serum and liver of the mice. Results showed that KEP is mainly composed of glucose, rhamnose, arabinose, and galactose. It has certain DPPH and ABTS free radical scavenging ability and good α-glucosidase inhibitory ability, indicating that KEP has the potential to improve blood glucose levels in diabetes patients. The experimental results of KEP treatment on mice showed that KEP could control the continuous increase of fasting blood glucose levels. The potential mechanisms behind this blood glucose level control composes of (1) increasing the glucokinase and C peptide levels and decreasing Glucose-6-phosphatase content for improving key enzyme activity in the glucose metabolism pathway. This promotes the consumption of blood glucose during glycolysis, thereby inhibiting the production of endogenous glucose in gluconeogenesis pathway; (2) reducing triglyceride, total cholesterol, low density lipoprotein cholesterol, and increasing high density lipoprotein cholesterol content, for regulating blood lipid indicators to normal levels; and (3) by improving the activities of catalase, glutathione peroxidase, and antioxidant enzymes superoxide dismutase for further improving the antioxidant defense system in the body to reduce blood glucose.

Redox signaling and metabolism in Alzheimer's disease

Reduction and oxidation reactions are essential for biochemical processes. They are part of metabolic pathways and signal transduction. Reactive oxygen species (ROS) as second messengers and oxidative modifications of cysteinyl (Cys) residues are key to transduce and translate intracellular and intercellular signals. Dysregulation of cellular redox signaling is known as oxidative distress, which has been linked to various pathologies, including neurodegeneration. Alzheimer's disease (AD) is a neurodegenerative pathology linked to both, abnormal amyloid precursor protein (APP) processing, generating Aβ peptide, and Tau hyperphosphorylation and aggregation. Signs of oxidative distress in AD include: increase of ROS (H2O2, O2 •-), decrease of the levels or activities of antioxidant enzymes, abnormal oxidation of macromolecules related to elevated Aβ production, and changes in mitochondrial homeostasis linked to Tau phosphorylation. Interestingly, Cys residues present in APP form disulfide bonds that are important for intermolecular interactions and might be involved in the aggregation of Aβ. Moreover, two Cys residues in some Tau isoforms have been shown to be essential for Tau stabilization and its interaction with microtubules. Future research will show the complexities of Tau, its interactome, and the role that Cys residues play in the progression of AD. The specific modification of cysteinyl residues in redox signaling is also tightly connected to the regulation of various metabolic pathways. Many of these pathways have been found to be altered in AD, even at very early stages. In order to analyze the complex changes and underlying mechanisms, several AD models have been developed, including animal models, 2D and 3D cell culture, and ex-vivo studies of patient samples. The use of these models along with innovative, new redox analysis techniques are key to further understand the importance of the redox component in Alzheimer's disease and the identification of new therapeutic targets in the future.

Identification of Metabolic Signature Associated with Idiopathic Inflammatory Myopathy Reveals Polyamine Pathway Alteration in Muscle Tissue

Idiopathic inflammatory myopathy (IIM) is hard to diagnose without a muscle biopsy. We aimed to identify a metabolite panel for IIM detection by metabolomics approach in serum samples and to explore the metabolomic signature in tissue samples from a mouse model. We obtained serum samples from IIM patients, ankylosing spondylitis (AS) patients, healthy volunteers and muscle tissue samples from IIM murine model. All samples were subjected to a targeted metabolomic approach with various statistical analyses on serum and tissue samples to identify metabolic alterations. Three machine learning methods, such as logistic regression (LR), support vector machine (SVM), and random forest (RF), were applied to build prediction models. A set of 7 predictive metabolites was calculated using backward stepwise selection, and the model was evaluated within 5-fold cross-validation by using three machine algorithms. The model produced an area under the receiver operating characteristic curve values of 0.955 (LR), 0.908 (RF) and 0.918 (SVM). A total of 68 metabolites were significantly changed in mouse tissue. Notably, the most influential pathways contributing to the inflammation of muscle were the polyamine pathway and the beta-alanine pathway. Our metabolomic approach offers the potential biomarkers of IIM and reveals pathologically relevant metabolic pathways that are associated with IIM.

Aberrant Transferrin and Ferritin Upregulation Elicits Iron Accumulation and Oxidative Inflammaging Causing Ferroptosis and Undermines Estradiol Biosynthesis in Aging Rat Ovaries by Upregulating NF-Κb-Activated Inducible Nitric Oxide Synthase: First Demonstration of an Intricate Mechanism

We report herein a novel mechanism, unraveled by proteomics and validated by in vitro and in vivo studies, of the aberrant aging-associated upregulation of ovarian transferrin and ferritin in rat ovaries. The ovarian mass and serum estradiol titer plummeted while the ovarian labile ferrous iron and total iron levels escalated with age in rats. Oxidative stress markers, such as nitrite/nitrate, 3-nitrotyrosine, and 4-hydroxy-2-nonenal, accumulated in the aging ovaries due to an aberrant upregulation of the ovarian transferrin, ferritin light/heavy chains, and iron regulatory protein 2(IRP2)-mediated transferrin receptor 1 (TfR1). Ferritin inhibited estradiol biosynthesis in ovarian granulosa cells in vitro via the upregulation of a nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and p65/p50-induced oxidative and inflammatory factor inducible nitric oxide synthase (iNOS). An in vivo study demonstrated how the age-associated activation of NF-κB induced the upregulation of iNOS and the tumor necrosis factor α (TNFα). The downregulation of the keap1-mediated nuclear factor erythroid 2-related factor 2 (Nrf2), that induced a decrease in glutathione peroxidase 4 (GPX4), was observed. The aberrant transferrin and ferritin upregulation triggered an iron accumulation via the upregulation of an IRP2-induced TfR1. This culminates in NF-κB-iNOS-mediated ovarian oxi-inflamm-aging and serum estradiol decrement in naturally aging rats. The iron accumulation and the effect on ferroptosis-related proteins including the GPX4, TfR1, Nrf2, Keap1, and ferritin heavy chain, as in testicular ferroptosis, indicated the triggering of ferroptosis. In young rats, an intraovarian injection of an adenovirus, which expressed iron regulatory proteins, upregulated the ovarian NF-κB/iNOS and downregulated the GPX4. These novel findings have contributed to a prompt translational research on the ovarian aging-associated iron metabolism and aging-associated ovarian diseases.

In Vitro Mimicking of Obesity-Induced Biochemical Environment to Study Obesity Impacts on Cells and Tissues

Obesity represents a heavy burden for modern healthcare. The main challenge facing obesity research progress is the unknown underlying pathways, which limits our understanding of the pathogenesis and developing therapies. Obesity induces specific biochemical environments that impact the different cells and tissues. In this piece of writing, we suggest mimicking obesity-induced in vivo biochemical environments including pH, lipids, hormones, cytokines, and glucose within an in vitro environment. The concept is to reproduce such biochemical environments and use them to treat the tissue cultures, explant cultures, and cell cultures of different biological organs. This will allow us to clarify how the obesity-induced biochemistry impacts such biological entities. It would also be important to try different environments, in terms of the compositions and concentrations of the constitutive elements, in order to establish links between the effects (impaired regeneration, cellular inflammation, etc.) and the factors constituting the environment (hormones, cytokines, etc.) as well as to reveal dose-dependent effects. We believe that such approaches will allow us to elucidate obesity mechanisms, optimize animal models, and develop therapies as well as novel tissue engineering applications.

Evaluation of oxidative stress in degenerative rotator cuff tears

BACKGROUND

Oxidative stress occurs as a result of the disruption of the balance between the formations of reactive oxygen species and antioxidant defense mechanisms during the conversion of nutrients into energy. Increased body oxidative stress has been reported to be involved in the etiology of several degenerative and chronic diseases. We hypothesized that the body oxidative stress level is higher in patients with atraumatic degenerative rotator cuff tear than that in healthy individuals.

METHODS

The patients who underwent arthroscopic repair for atraumatic, degenerative rotator cuff tear were prospectively evaluated. A total of 30 patients (group 1, 19 females and 11 males; mean age: 57.33 ± 6.96 years; range: 50-77 years) and 30 healthy individuals (group 2, 18 females and 12 males; mean age: 56.77 ± 6 years; range: 51-72 years) were included in the study. The Constant and American Shoulder and Elbow Surgeons scoring systems were used to evaluate the clinical outcomes. Serum oxidative stress parameters of the patients and the control group were biochemically evaluated. Accordingly, thiol/disulfide (DS) balance (DS/native thiol [NT], DS/total thiol [TT]), Total Oxidant Status (TOS), oxidative stress index, and nuclear factor erythroid-2-associated factor-2 values were used as the biochemical parameters indicating an increase in the serum oxidative stress level. Total antioxidant status and NT/TT values served as the biochemical parameters indicating a decrease in the serum oxidative stress level.

RESULTS

The study follow-up duration was 12 months. A statistically significant increase was observed in American Shoulder and Elbow Surgeons and Constant scores of patients who underwent arthroscopic rotator cuff repair relative to that during the preoperative period (P = .01). The values of biochemical parameters (DS/NT, DS/TT, TOS, oxidative stress index, and nuclear factor erythroid-2-associated factor-2), which indicated an increase in the serum oxidative stress, were significantly higher in preoperative patients than those in postoperative patients, albeit the control group values were significantly lower than those of the postoperative patients. The biochemical parameters (NT/TT and total antioxidant status) indicating a decrease in the serum oxidative stress levels were significantly higher in the postoperative patients than those in the preoperative patients and significantly lower than those in the control group.

CONCLUSION

High levels of markers indicating an increase in the serum oxidative stress in patients with degenerative rotator cuff rupture suggested that TOS may be involved in the etiopathogenesis of rotator cuff degeneration. Although the oxidative load decreases during the postoperative period, the fact that it is still higher than that in healthy individuals supports this claim.

Does age pay off? Effects of three-generational experiments of nanodiamond exposure and withdrawal in wild and longevity-selected model animals

Nanodiamonds (NDs) are considered a material with low toxicity. However, no studies describe the effects of ND withdrawal after multigenerational exposure. The aim was to evaluate ND exposure (in the 1st and 2nd generations) effects at low concentrations (0.2 or 2 mg kg^-1) and withdrawal (in the 3rd generation) in the wild (H) and longevity-selected (D) model insect Acheta domesticus. We measured selected oxidative stress parameters, immunity, types of cell death, and DNA damage. Most of the results obtained in the 1st generation, e.g., catalase (CAT), total antioxidant capacity (TAC), heat shock proteins (HSP70), defensins, or apoptosis level, confirmed no significant toxicity of low doses of NDs. Interestingly, strain-specific differences were observed. D-strain crickets reduced autophagy, the number of ROS+ cells, and DNA damage. The effect can be a symptom of mobilization of the organism and stimulation of physiological defense mechanisms in long-living organisms. The 2nd-generation D-strain insects fed ND-spiked food at higher concentrations manifested a reduction in CAT, TAC, early apoptosis, and DNA damage, together with an increase in HSP70 and defensins. ROS+ cells and cells with reduced membrane potential and autophagy did not differ significantly from the control. H-strain insects revealed a higher number of ROS+ cells and cells with reduced membrane potential, decreased CAT activity, and early apoptosis. Elimination of NDs from the diet in the 3rd generation did not cause full recovery of the measured parameters. We noticed an increase in the concentration of HSP70 and defensins (H-strain) and a decrease in apoptosis (D-strain). However, the most visible increase was a significant increase in DNA damage, especially in H-strain individuals. The results suggest prolonged adverse effects of NDs on cellular functions, reaching beyond "contact time" with these particles. Unintentional and/or uncontrolled ND pollution of the environment poses a new challenge for all organisms inhabiting it, particularly during multigenerational exposure.

A Multitarget Therapeutic Peptide Derived From Cytokine Receptors Based on in Silico Analysis Alleviates Cytokine-Stimulated Inflammation

Septicemia is a severe inflammatory response caused by the invasion of foreign pathogens. Severe sepsis-induced shock and multiple organ failure are the two main causes of patient death. The overexpression of many proinflammatory cytokines, such as TNF-α, IL-1β, and IL-6, is closely related to severe sepsis. Although the treatment of sepsis has been subject to many major breakthroughs of late, the treatment of patients with septic shock is still accompanied by a high mortality rate. In our previous research, we used computer simulations to design the multifunctional peptide KCF18 that can bind to TNF-α, IL-1β, and IL-6 based on the binding regions of receptors and proinflammatory cytokines. In this study, proinflammatory cytokines were used to stimulate human monocytes to trigger an inflammatory response, and the anti-inflammatory ability of the multifunctional KCF18 peptide was further investigated. Cell experiments demonstrated that KCF18 significantly reduced the binding of proinflammatory cytokines to their cognate receptors and inhibited the mRNA and protein expressions of TNF-α, IL-1β, and IL-6. It could also reduce the expression of reactive oxygen species induced by cytokines in human monocytes. KCF18 could effectively decrease the p65 nucleus translocation induced by cytokines, and a mice endotoxemia experiment demonstrated that KCF18 could reduce the expression of IL-6 and the increase of white blood cells in the blood stimulated by lipopolysaccharides. According to our study of tissue sections, KCF18 alleviated liver inflammation. By reducing the release of cytokines in plasma and directly affecting vascular cells, KCF18 is believed to significantly reduce the risk of vascular inflammation.

Control of Reactive Oxygen Species through Antioxidant Enzymes Plays a Pivotal Role during the Cultivation of Neopyropia yezoensis

Neopyropia yezoensis is an economically important marine crop that can survive dehydrating conditions when nets are lifted from seawater. During this process, production of oxygen radicals and the resulting up-regulation of antioxidant enzymes mediated by the abscisic acid (ABA) signaling pathway played an important role. However, there were no reports about the significance regarding the protection of seaweed throughout the entire production season. Especially, in new aquatic farms in Shandong Province that were formed when traditional N. yezoensis cultivation moved north. Here, we determined the levels of ABA, hydrogen peroxide (H2O2), soluble protein, chlorophyll, and cell wall polysaccharides in samples collected at different harvest periods from Jimo aquatic farm, Shandong Province. The activities and expression of NADPH oxidase (NOX) and antioxidant enzymes in the corresponding samples were also determined. Combined with the monitoring data of sea surface temperature and solar light intensity, we proposed that the cultivation of N. yezoensis in Shandong Province was not affected by high-temperature stress. However, photoinhibition in N. yezoensis usually occurs at noon, especially in March. Both the activities and the expression of NOX and antioxidant enzymes were up-regulated continuously. It is reasonable to speculate that the reactive oxygen species (ROS) produced by NOX induced the up-regulation of antioxidant enzymes through the ABA signaling pathway. Although antioxidant enzymes play a pivotal role during the cultivation of N. yezoensis, the production of ROS also caused a shift in gene expression, accumulation of secondary metabolites, and even decreased the chlorophyll pool size, which eventually led to a decrease in algae assimilation. Accordingly, we suggest that the dehydration of N. yezoensis nets should be adopted when necessary and the extent of dehydration should be paid special consideration to avoid an excessive cellular response caused by ROS.

Inflammatory potential of diet and bone mineral density in a senior Mediterranean population: a cross-sectional analysis of PREDIMED-Plus study

PURPOSE

Inflammation could play a key role in tissue damage and bone metabolism. The modified dietary inflammatory score (M-DIS) is a validated tool to estimate the inflammatory potential of the diet. In the present study, we evaluate the associations between the M-DIS and bone mineral density (BMD) in a senior Mediterranean population with overweight/obesity and metabolic syndrome.

METHODS

Baseline cross-sectional association between the M-DIS and bone mineral density was assessed in 1134 participants of the multicenter PREDIMED-Plus trial (aged 55-75 with overweight/obesity and metabolic syndrome). BMD was measured using Dual-energy X-ray Absorptiometry scans and participants answered a food frequency questionnaire to determine the M-DIS. BMD was categorized as low BMD when T score was equal or lower than -1 and normal BMD in another case. Associations between BMD and M-DIS were evaluated by using linear and logistic regressions adjusted by other co-variates.

RESULTS

Participants in the top tertile of the M-DIS had a lower BMD at total femur [β (95% CI) - 0.02 (- 0.04, - 0.01)], trochanter areas [β (95% CI) - 0.03 (- 0.05, - 0.01)] and lumbar spine area [β (95% CI) - 0.03 (- 0.07, 0.01)] (but in the last case, measures were less precise and hence not statistically significant) compared to those in the lower M-DIS tertile. Multiple logistic regression analyses showed that the odds of the total femur and femoral trochanter osteopenia/osteoporosis were higher in participants in the top tertile compared to those in the lowest tertile of M-DIS [OR (95% CI) 1.71 (1.12, 2.64), P for trend 0.015; 2.02 (1.29, 3.21), P for trend 0.002, respectively].

CONCLUSION

A high pro-inflammatory diet, measured by the M-DIS, is associated with lower BMD in a senior Mediterranean population with metabolic syndrome.

A novel mechanism linking ferroptosis and endoplasmic reticulum stress via the circPtpn14/miR-351-5p/5-LOX signaling in melatonin-mediated treatment of traumatic brain injury

Traumatic brain injury (TBI) can lead to disability or devastating consequences with few established treatments. Although ferroptosis has been shown to be involved in TBI, the underlying mechanism was rarely known. Melatonin has been indicated to exhibit neuroprotective activities. However, the anti-ferroptotic effects of melatonin on TBI have not yet to be elucidated. We aimed to investigate whether ferroptosis was induced in humans after TBI and whether ferroptosis inhibition by melatonin could protect against blood-brain barrier (BBB) damage after TBI in vivo and in vitro. Circular RNAs (circRNAs) are highly expressed in the brain. For the first time, differentially expressed circRNA after melatonin treatment for TBI were detected by RNA sequencing. We found that lipid peroxidation was induced in humans after TBI, while melatonin significantly improved brain function of mice after TBI and alleviated ferroptosis and endoplasmic reticulum (ER) stress in vivo and in vitro. A total of 1826 differentially expressed circRNAs were found (fold change >2, Q < 0.01), including 921 down-regulated and 905 up-regulated circRNAs in the injured brain tissues of TBI mice receiving melatonin treatment. Mechanistically, melatonin administration reduced the level of circPtpn14 (mmu_circ_0000130), which functioned by acting as a miR-351-5p sponge to positively regulate the expression of the ferroptosis-related 5-lipoxygenase (5-LOX). Moreover, circPtpn14 overexpression partly abolished the inhibitory effects of melatonin on ferroptosis. Collectively, our findings provide the first evidence that melatonin could exert anti-ferroptotic and anti-ER stress effects in brain injury by alleviating lipid peroxidation via the circPtpn14/miR-351-5p/5-LOX signaling.

Enhancement of Biocontrol Efficacy of Pichia kudriavzevii Induced by Ca Ascorbate against Botrytis cinerea in Cherry Tomato Fruit and the Possible Mechanisms of Action

This study investigated the effect of Ca ascorbate on the biocontrol efficacy of Pichia kudriavzevii and the possible mechanisms. The results indicated that the biocontrol activity of P. kudriavzevii was significantly enhanced by 0.15 g L⁻¹ of Ca ascorbate, with higher growth rates of yeast cells in vitro and in vivo. The antioxidant enzyme activity in P. kudriavzevii, including catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), were improved by Ca ascorbate and reached the maximum at 96 h, 96 h, and 72 h, respectively. The expression of the antioxidant enzyme-related genes CAT1 (8.55-fold) and SOD2 (7.26-fold) peaked at 96 h, while PRXIID (2.8-fold) peaked at 48 h, which were similar to the trends of enzyme activities. Compared with the control, 0.15 g L⁻¹ of Ca ascorbate and CaCl₂ increased the activity of succinate dehydrogenase in P. kudriavzevii, thereby enhancing the utilization of nutrients by yeast cells, and calcium ascorbate had the strongest effect. The expressions of HXT5, ADH6, PET100p, and Pga62 were significantly higher in the Ca ascorbate treatment than the other groups, and the CaCl₂ treatment was also significantly higher than the control. These results indicated that Ca ascorbate can effectively improve the energy metabolism and cell wall synthesis and slow down the senescence of yeast cells. In general, Ca ascorbate can improve the environmental adaptability of P. kudriavzevii and thus improve the biocontrol effect, which is associated with inducing antioxidant enzymes in yeast cells and enhancing energy metabolism and nutrient utilization efficiency to increase nutrient competition with pathogens.

IMPORTANCE Antagonistic yeast is a promising way to control postharvest fruit decay because of its safety and broad-spectrum resistance. However, the biocontrol efficacy of yeast is limited by environmental stress, such as oxidative stress. Therefore, the improvement of antioxidant capacity has become a research hot spot in improving the biocontrol efficacy of yeast. The induction of Ca ascorbate on the antioxidant capacity and physiological activity of yeast was studied. The results showed better induction of antioxidant enzyme and physiological activity in yeast by Ca ascorbate for better antioxidant capacity, and Ca²⁺ also played a synergistic promotion effect, which improved the biocontrol efficacy. These results provide an approach for the research and application of improving the environmental adaptability and biocontrol effectiveness of yeast.

UPLC-PDA-ESI-QTOF-MS/MS fingerprint of purified flavonoid enriched fraction of Bryophyllum pinnatum; antioxidant properties, anticholinesterase activity and in silico studies

CONTEXT

Bryophyllum pinnatum (Lam.) Oken (Crassulaceae) is used traditionally to treat many ailments.

OBJECTIVES

This study characterizes the constituents of B. pinnatum flavonoid-rich fraction (BPFRF) and investigates their antioxidant and anticholinesterase activity using in vitro and in silico approaches.

MATERIALS AND METHODS

Methanol extract of B. pinnatum leaves was partitioned to yield the ethyl acetate fraction. BPFRF was isolated from the ethyl acetate fraction and purified. The constituent flavonoids were structurally characterized using UPLC-PDA-MS². Antioxidant activity (DPPH), Fe²⁺-induced lipid peroxidation (LP) and anticholinesterase activity (Ellman's method) of the BPFRF and standards (ascorbic acid and rivastigmine) across a concentration range of 3.125-100 μg/mL were evaluated in vitro for 4 months. Molecular docking was performed to give insight into the binding potentials of BPFRF constituents against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE).

RESULTS

UPLC-PDA-MS² analysis of BPFRF identified carlinoside, quercetin (most dominant), luteolin, isorhamnetin, luteolin-7-glucoside. Carlinoside was first reported in this plant. BPFRF significantly inhibited DPPH radical (IC₅₀ = 7.382 ± 0.79 µg/mL) and LP (IC₅₀ = 7.182 ± 0.60 µg/mL) better than quercetin and ascorbic acid. Also, BPFRF exhibited potent inhibition against AChE and BuChE with IC₅₀ values of 22.283 ± 0.27 µg/mL and 33.437 ± 1.46 µg/mL, respectively compared to quercetin and rivastigmine. Docking studies revealed that luteolin-7-glucoside, carlinoside and quercetin interact effectively with crucial amino acid residues of AChE and BuChE through hydrogen bonds.

DISCUSSION AND CONCLUSIONS

BPFRF possesses an excellent natural source of cholinesterase inhibitor and antioxidant. The material could be further explored for the potential treatment of oxidative damage and cholinergic dysfunction in Alzheimer's disease.

Fundamentals of Membrane Lipid Replacement: A Natural Medicine Approach to Repairing Cellular Membranes and Reducing Fatigue, Pain, and Other Symptoms While Restoring Function in Chronic Illnesses and Aging

Membrane Lipid Replacement (MLR) uses natural membrane lipid supplements to safely replace damaged, oxidized lipids in membranes in order to restore membrane function, decrease symptoms and improve health. Oral MLR supplements contain mixtures of cell membrane glycerolphospholipids, fatty acids, and other lipids, and can be used to replace and remove damaged cellular and intracellular membrane lipids. Membrane injury, caused mainly by oxidative damage, occurs in essentially all chronic and acute medical conditions, including cancer and degenerative diseases, and in normal processes, such as aging and development. After ingestion, the protected MLR glycerolphospholipids and other lipids are dispersed, absorbed, and internalized in the small intestines, where they can be partitioned into circulating lipoproteins, globules, liposomes, micelles, membranes, and other carriers and transported in the lymphatics and blood circulation to tissues and cellular sites where they are taken in by cells and partitioned into various cellular membranes. Once inside cells, the glycerolphospholipids and other lipids are transferred to various intracellular membranes by lipid carriers, globules, liposomes, chylomicrons, or by direct membrane-membrane interactions. The entire process appears to be driven by 'bulk flow' or mass action principles, where surplus concentrations of replacement lipids can stimulate the natural exchange and removal of damaged membrane lipids while the replacement lipids undergo further enzymatic alterations. Clinical studies have demonstrated the advantages of MLR in restoring membrane and organelle function and reducing fatigue, pain, and other symptoms in chronic illness and aging patients.

Nutritional Significance and Antioxidant-Mediated Antiaging Effects of Finger Millet: Molecular Insights and Prospects

Aging is a multifaceted process that is associated with progressive, lethal, and unalterable changes like damage to different molecules (DNA, proteins, and lipids), cells, tissues, and organs. It is an inevitable process but can be delayed by both genetic and dietary interventions. Besides aging, premature death and age-associated diseases can be dealt with diet regulation and the use of compounds that inhibit the stress responsiveness or promote the damage repair signaling pathways. Natural compounds offer a repertoire of highly diverse structural scaffolds that can offer hopeful candidate chemical entities with antiaging potential. One such source of natural compounds is millets, which are minor cereals with an abundance of high fiber, methionine, calcium, iron, polyphenols, and secondary metabolites, responsible for numerous potential health benefits. The present review article elucidates the nature and significance of different phytochemicals derived from millets with a major focus on finger millet and highlights all the important studies supporting their health benefits with special emphasis on the antiaging effect of these compounds. The present article also proposes the possible mechanisms through which millets can play a significant role in the suppression of aging processes and aging-related diseases by influencing genetic repair, protein glycation, and stress-responsive pathways. We further discuss well-established natural compounds for their use as antiaging drugs and recommend raising awareness for designing novel formulations/combinations from them so that their maximum antiaging potential can be harnessed for the benefit of mankind.

Oklahoma Nathan Shock Aging Center - assessing the basic biology of aging from genetics to protein and function

The Oklahoma Shock Nathan Shock Center is designed to deliver unique, innovative services that are not currently available at most institutions. The focus of the Center is on geroscience and the development of careers of young investigators. Pilot grants are provided through the Research Development Core to junior investigators studying aging/geroscience throughout the USA. However, the services of our Center are available to the entire research community studying aging and geroscience. The Oklahoma Nathan Shock Center provides researchers with unique services through four research cores. The Multiplexing Protein Analysis Core uses the latest mass spectrometry technology to simultaneously measure the levels, synthesis, and turnover of hundreds of proteins associated with pathways of importance to aging, e.g., metabolism, antioxidant defense system, proteostasis, and mitochondria function. The Genomic Sciences Core uses novel next-generation sequencing that allows investigators to study the effect of age, or anti-aging manipulations, on DNA methylation, mitochondrial genome heteroplasmy, and the transcriptome of single cells. The Geroscience Redox Biology Core provides investigators with a comprehensive state-of-the-art assessment of the oxidative stress status of a cell, e.g., measures of oxidative damage and redox couples, which are important in aging as well as many major age-related diseases as well as assays of mitochondrial function. The GeroInformatics Core provides investigators assistance with data analysis, which includes both statistical support as well as analysis of large datasets. The Core also has developed number of unique software packages to help with interpretation of results and discovery of new leads relevant to aging. In addition, the Geropathology Research Resource in the Program Enhancement Core provides investigators with pathological assessments of mice using the recently developed Geropathology Grading Platform.

Rejigging Electron and Proton Transfer to Transition between Dioxygenase, Monooxygenase, Peroxygenase, and Oxygen Reduction Activity: Insights from Bioinspired Constructs of Heme Enzymes

Nature has employed heme proteins to execute a diverse set of vital life processes. Years of research have been devoted to understanding the factors which bias these heme enzymes, with all having a heme cofactor, toward distinct catalytic activity. Among them, axial ligation, distal super structure, and substrate binding pockets are few very vividly recognized ones. Detailed mechanistic investigation of these heme enzymes suggested that several of these enzymes, while functionally divergent, use similar intermediates. Furthermore, the formation and decay of these intermediates depend on proton and electron transfer processes in the enzyme active site. Over the past decade, work in this group, using in situ surface enhanced resonance Raman spectroscopy of synthetic and biosynthetic analogues of heme enzymes, a general idea of how proton and electron transfer rates relate to the lifetime of different O2 derived intermediates has been developed. These findings suggest that the enzymatic activities of all these heme enzymes can be integrated into one general cycle which can be branched out to different catalytic pathways by regulating the lifetime and population of each of these intermediates. This regulation can further be achieved by tuning the electron and proton transfer steps. By strategically populating one of these intermediates during oxygen reduction, one can navigate through different catalytic processes to a desired direction by altering proton and electron transfer steps.

Bradykinin Protects Human Endothelial Progenitor Cells from High-Glucose-Induced Senescence through B2 Receptor-Mediated Activation of the Akt/eNOS Signalling Pathway

BACKGROUND

Circulating endothelial progenitor cells (EPCs) play important roles in vascular repair. However, the mechanisms of high-glucose- (HG-) induced cord blood EPC senescence and the role of B2 receptor (B2R) remain unknown.

METHODS

Cord blood samples from 26 patients with gestational diabetes mellitus (GDM) and samples from 26 healthy controls were collected. B2R expression on circulating CD34+ cells of cord blood mononuclear cells (CBMCs) was detected using flow cytometry. The plasma concentrations of 8-isoprostaglandin F2α (8-iso-PGF2α) and nitric oxide (NO) were measured. EPCs were treated with HG (40 mM) alone or with bradykinin (BK) (1 nM). The B2R and eNOS small interfering RNAs (siRNAs) and the PI3K antagonist LY294002 were added to block B2R, eNOS, and PI3K separately. To determine the number of senescent cells, senescence-associated β-galactosidase (SA-β-gal) staining was performed. The level of mitochondrial reactive oxygen species (ROS) in EPCs was assessed by Mito-Sox staining. Cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assays. Mitochondrial DNA (mtDNA) copy number and the relative length of telomeres were detected by real time-PCR. The distribution of human telomerase reverse transcriptase (hTERT) in the nucleus, cytosol, and mitochondria of EPCs was detected by immunofluorescence. The expression of B2R, p16, p21, p53, P-Ser473AKT, T-AKT, eNOS, and hTERT was demonstrated by Western blot.

RESULTS

B2R expression on circulating CD34+ cells of CBMCs was significantly reduced in patients with GDM compared to healthy controls. Furthermore, B2R expression on circulating CD34+ cells of CBMCs was inversely correlated with plasma 8-iso-PGF2α concentrations and positively correlated with plasma NO levels. BK treatment decreased EPC senescence and ROS generation. Furthermore, BK treatment of HG-exposed cells led to elevated P-Ser473AKT and eNOS protein expression compared with HG treatment alone. BK reduced hTERT translocation in HG-induced senescent EPCs. B2R siRNA, eNOS siRNA, and antagonist of the PI3K signalling pathway blocked the protective effects of BK.

CONCLUSION

BK, acting through PI3K-AKT-eNOS signalling pathways, reduced hTERT translocation, increased the relative length of telomeres while reducing mtDNA copy number, and finally protected against EPC senescence induced by HG.

Cacao powder supplementation attenuates oxidative stress, cholinergic impairment, and apoptosis in D-galactose-induced aging rat brain

Aging, a critical risk factor of several diseases, including neurodegenerative disorders, affects an ever-growing number of people. Cacao supplementation has been suggested to improve age-related neuronal deficits. Therefore, this study investigated the protective effects of raw cacao powder on oxidative stress-induced aging. Male Sprague-Dawley rats were divided into 4 groups: Control (C), D-galactose-induced aging (G), D-galactose injection with 10% (LC), and 16% (HC) cacao powder mixed diet. D-galactose (300 mg/3 mL/kg) was intraperitoneally injected into all but the control group for 12 weeks. Cacao supplemented diets were provided for 8 weeks. The levels of serum Malondialdehyde (MDA), Advanced Glycation End-products (AGEs), brain and liver MDA, the indicators of the D-galactose induced oxidative stress were significantly decreased in LC and HC but increased in G. The Acetylcholinesterase (AChE) activity of brain showed that the cholinergic impairment was significantly lower in LC, and HC than G. Furthermore, the expression levels of catalase (CAT), phospho-Akt/Akt, and procaspase-3 were significantly increased in LC and HC. In conclusion, cacao consumption attenuated the effects of oxidative stress, cholinergic impairment and apoptosis, indicating its potential in future clinical studies.

Anti-Diabetic and Antioxidant Activities of Red Wine Concentrate Enriched with Polyphenol Compounds under Experimental Diabetes in Rats

We obtained red wine concentrate, which was enriched with natural polyphenolic compounds (PC concentrate). The main purpose was to study the hypoglycemic and antioxidant effects of the red wine concentrate, and its impact on key hematological parameters of rats with experimental diabetes mellitus. While administrating the red wine concentrate to rats with diabetes, partial recovering of glucose tolerance was promoted, as well as normalization of glycated hemoglobin level, an increase in the quantity of erythrocytes and hemoglobin concentration. PC concentrate had anti-radical effect, which was determined using 2,2-diphenyl-1-picrylhydrazylradical (DPPH) method and effectively inhibited oxidation of phosphatidylcholine liposomes, induced by 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) as a free radical generator. It was also confirmed that PC concentrate had antioxidant properties in vivo. The contents of lipid peroxidation and protein oxidation products, the activity of catalase, and glutathione peroxidase (GPx) were increased in the plasma of rats with diabetes mellitus. At the same time, the activity of superoxide dismutase (SOD) was decreased. The concentrate of red wine had a corrective effect on investigated indicators and caused their normalization in plasma of diabetic animals.

The Evolution of the Hallmarks of Aging

The evolutionary theory of aging has set the foundations for a comprehensive understanding of aging. The biology of aging has listed and described the "hallmarks of aging," i.e., cellular and molecular mechanisms involved in human aging. The present paper is the first to infer the order of appearance of the hallmarks of bilaterian and thereby human aging throughout evolution from their presence in progressively narrower clades. Its first result is that all organisms, even non-senescent, have to deal with at least one mechanism of aging - the progressive accumulation of misfolded or unstable proteins. Due to their cumulation, these mechanisms are called "layers of aging." A difference should be made between the first four layers of unicellular aging, present in some unicellular organisms and in all multicellular opisthokonts, that stem and strike "from the inside" of individual cells and span from increasingly abnormal protein folding to deregulated nutrient sensing, and the last four layers of metacellular aging, progressively appearing in metazoans, that strike the cells of a multicellular organism "from the outside," i.e., because of other cells, and span from transcriptional alterations to the disruption of intercellular communication. The evolution of metazoans and eumetazoans probably solved the problem of aging along with the problem of unicellular aging. However, metacellular aging originates in the mechanisms by which the effects of unicellular aging are kept under control - e.g., the exhaustion of stem cells that contribute to replace damaged somatic cells. In bilaterians, additional functions have taken a toll on generally useless potentially limited lifespan to increase the fitness of organisms at the price of a progressively less efficient containment of the damage of unicellular aging. In the end, this picture suggests that geroscience should be more efficient in targeting conditions of metacellular aging rather than unicellular aging itself.

Unravelling Melatonin's Varied Antioxidizing Protection of Membrane Lipids Determined by its Spatial Distribution

The antioxidizing capability of membrane antioxidants is strongly affected by the submolecular regions of the membrane that they locate. However, the concurrent determination of their location in the membranes and the consequent antioxidizing effect remains difficult. Using our field-induced droplet ionization mass spectrometry methodology, here we show the rapid determination of the antioxidation effect and the spatial distribution of melatonin in POPC membranes. Melatonin effectively protects the membrane lipids against hydroxyl radicals originating from the Fenton reactions in the water phase but cannot protect the lipids against singlet oxygen generated by a lipophilic photosensitizer in the lipid tail region (oil phase). These varied antioxidizing behaviors indicate that melatonin dwells at the headgroup subregion of the membranes. We anticipate that the methodology in this study can be widely utilized in the screening of antioxidants' spatial distribution and antioxidizing efficiency, and eventually in designing novel antioxidants that could deliver specific functions.

Association of Recurrent Tear After Arthroscopic Rotator Cuff Repair and Superoxide-Induced Oxidative Stress

BACKGROUND

Recurrent tears after arthroscopic rotator cuff repair (ARCR) remain a significant clinical problem. Oxidative stress contributes to the degeneration of the rotator cuff, and a degenerative rotator cuff can lead to recurrent tear after ARCR. However, the correlation between oxidative stress and retear after ARCR is unclear.

PURPOSE

To investigate the correlation between superoxide-induced oxidative stress and recurrent tear after ARCR.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

A total of 68 patients who underwent ARCR using a suture-bridge technique participated in this study. Specimens were collected from the edge of the torn tendon during surgery. The modified Bonar score was used to evaluate degeneration of the rotator cuff on histological specimens, and fluorescence intensity on dihydroethidium (DHE) staining was used to detect oxidative stress. Superoxide dismutase (SOD) enzyme activity was also measured. The following were used for clinical evaluation: age, tear size on magnetic resonance imaging (MRI) before surgery, Goutallier classification on MRI before surgery, and Japanese Orthopaedic Association score before and 6 months after surgery. After the repaired rotator cuffs were evaluated on MRI 6 months after surgery, the patients were divided into groups: those with a healed rotator cuff (healed group; n = 46) and those with a recurrent tear (retear group; n = 22). The significant differences between the groups were determined with regard to clinical evaluation, modified Bonar score, DHE intensity, and SOD activity. In addition, multivariate logistic regression analysis was performed to investigate risk factors for recurrent tear.

RESULTS

Age, tear size, Goutallier classification, modified Bonar score, DHE intensity, and SOD activity were significantly greater in the retear group than in the healed group, although the Japanese Orthopaedic Association score was not significantly different. Multiple logistic regression analysis demonstrated that age, tear size, and SOD activity were significantly correlated with recurrent tear.

CONCLUSION

In addition to tear size and age, superoxide-induced oxidative stress may be an exacerbating factor for retear after ARCR.

Combination of cyanidin-3-O-glucoside and cisplatin induces oxidative stress and apoptosis in HeLa cells by reducing activity of endogenous antioxidants, increasing bax/bcl-2 mRNA expression ratio, and downregulating Nrf2 expression

Investigation on potentiation of existing drugs with natural compounds to enhance efficacy and reduce toxic effect of the drugs has been increasing in recent years. This paper reports cytotoxic effect (apoptosis-related and oxidative stress-related effect) of cyanidin-3-O-glucoside (C3G), cisplatin (DDP), and their combination (C3G-DDP) on cervical cancer HeLa cells. Concentration of intracellular reactive oxygen species (ROS) was determined by employing fluorescent marker 2',7'-dichlorodihydrofluorescein diacetate. On the other hand, malondialdehyde (MDA) and glutathione (GSH) concentration, and activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were quantitated by commercially available assay kits. C3G-DDP significantly inhibited the activity of SOD, CAT, and GSH-Px. Simultaneously, C3G-DDP reduced GSH concentration while increased the concentration of ROS and MDA. Moreover, Western blot analysis suggested that C3G-DDP significantly reduced the expression of nuclear factor erythroid 2-related factor-2 (Nrf2) and Nrf2 target proteins: heme oxygenase-1 (HO-1) and NAD(P)H quinone dehydrogenase 1 (NQO1). In contrast, C3G-DDP increased the expression of Keap1. Furthermore, C3G-DDP significantly upregulated and downregulated the mRNA expressions of bax and bcl-2, respectively, thereby increasing bax/bcl-2 mRNA expression ratio. Overall, our findings propose that potentiation of DDP with C3G improves cancer cell susceptibility, specifically cervical cancer cells, to DDP. PRACTICAL APPLICATIONS: Cisplatin is recommended by most medical oncologists worldwide to treat cancer. Despite its neoplastic efficacy, it has undesirable side effects including nausea, vomiting, nephrotoxicity, and hepatotoxicity. Natural biologically active food ingredients are suggested to be used as antioxidants along with DDP therapy to prevent cisplatin-induced toxicity. C3G-DDP protected HeLa cells from oxidative stress by reducing NQO1 and HO-1 levels and regulated the Nrf2 signaling pathway. In addition, C3G-DDP protected HeLa cells from oxidative stress-induced apoptosis by increasing bcl-2 levels and decreasing bax levels. These results expanded our understanding of the role of C3G in a cervical cancer cell model, and provided a potential new treatment strategy for this cancer, as well as a theoretical basis for the development of new drugs in the future.

Diurnal relationship between core clock gene BMAL1, antioxidant SOD1 and oxidative RNA/DNA damage in young and older healthy women

BACKGROUND AND OBJECTIVES

BMAL1 is a core clock gene that positively regulates circadian rhythms. In animals, BMAL1 further acts as transcription factor for the SOD1 gene which encodes the major antioxidant enzyme superoxide dismutase. SOD1 protects against oxidative damage that is a major factor for human aging. Mice lacking mBmal1 exhibit premature aging phenotypes which might be related to a reduced expression of SOD1. The purpose of this study was to explore the circadian relationship between BMAL1, SOD1, oxidative RNA/DNA damage and aging in healthy humans.

SUBJECTS AND METHODS

In a cross-sectional study design, buccal mucosa cells and saliva samples were obtained from 21 young (23.7 ± 2.3 yrs) and 21 older women (66.8 ± 5.7 yrs) within 24 h at 4-h intervals (08:00, 12:00, 16:00, 20:00, 24:00 and 04:00 h). Transcript levels of BMAL1 and SOD1 were measured by real-time quantitative PCR. Protein levels of SOD1 were determined by immunoblotting and densitometry. Levels of oxidative RNA/DNA damage and melatonin were quantified by enzyme immunosorbent assays.

RESULTS

Transcript levels of BMAL1 and SOD1 mRNAs as well as protein levels of SOD1 and melatonin exhibited significant 24-h variation in each age group (P < 0.010, Friedman tests). The mRNA expression patterns of BMAL1 and SOD1 showed similar 24-h rhythmicity and positive relationships were found. Strongest relationships occurred in young women at 12:00 h (rs = 0.81, P = 0.005) and in older women at 08:00 h (r = 0.84, P < 0.001). Maximum levels of SOD1 mRNA appeared within 24 h in both age groups at 24:00 h. In both age groups, the timing of maximum level for SOD1 protein was delayed relative to the timing of maximum level for SOD1 mRNA. This delay was larger in older women (8 h) compared to young women (4 h). Older women showed higher oxidative RNA/DNA damage at all time-points compared to young women (P < 0.020). The oxidative RNA/DNA damage decreased continuously from 08:00 to 20:00 h (P < 0.001) in both age groups. Although oxidative damage and SOD1 protein levels declined simultaneously, only weak and non-significant relationships were noted.

CONCLUSIONS

This study demonstrates that transcript levels of SOD1 and protein level of SOD1 follow a circadian pattern of expression in healthy young and older women. The time-shift found between the 24-h maximum levels of SOD1 mRNA and SOD1 protein could be explained by the time needed for translation of SOD1 protein. The positive relationship found between expression levels of SOD1 mRNA and BMAL1 mRNA is in line with animal studies showing that BMAL1 acts as transcription factor and regulates the circadian synthesis of SOD1 mRNA. Differences between young and older women found in the timing of 24-h maxima as well as differences observed in 24-h relationships between characters might be due to age-related alterations in the circadian system. Absence of relationships between levels of SOD1 and oxidative RNA/DNA damage argue for a more complex interaction between the antioxidant system and the circadian system.

Antioxidation Defenses of Apis mellifera Queens and Workers Respond to Imidacloprid in Different Age-Dependent Ways: Old Queens Are Resistant, Foragers Are Not

Simple Summary

Honey bees are unique for studies on aging because queens live 40-fold longer than workers. An efficient antioxidant defense (ADS) is thought to be pivotal for longevity, but not always. How were different ADSs shaped by evolution in young and old queens and workers? Honey bees, the essential pollinators, are facing depopulation due, at least in part, to pesticides, such as imidacloprid, an oxidative stressor. Is an evolutionarily shaped ADS still useful for contemporary young and old queens/workers? Answering these questions is important for emerging oxidative-stress ecology and protecting contemporary honey bees. The ADS activity was determined in 1-day-old, 20-day-old, and 2-year-old queens and in 1-day-old and 20-day-old workers (foragers) fed without (control) or with low or high imidacloprid (in bee food). ADS was upregulated in workers with age but downregulated in queens. However, imidacloprid oxidative stress suppressed the active ADS in workers, particularly 20-day-old foragers, but not in 1-day-old queens. Unexpectedly, poor ADS activity in 2-year-old queens was highly upregulated by imidacloprid. Thus, queen and worker ADSs respond to imidacloprid in opposite ways, and old queens were still resistant, but foragers were not. This may be unfavorable for foragers dwelling in ecosystems that expose them to pesticides.

Abstract

We investigated how different antioxidant defenses (ADSs) were shaped by evolution in young/old Apis mellifera workers and queens to broaden the limited knowledge on whether ADSs are effective in contemporary pesticide environments and to complete bee oxidative-aging theory. We acquired 1-day-old, 20-day-old, and 2-year-old queens and 1-day-old and 20-day-old workers (foragers) fed 0, 5, or 200 ppb imidacloprid, a pesticide oxidative stressor. The activities of catalase, glutathione peroxidase, glutathione S-transferase, and superoxide dismutase and the level of total antioxidant potential were determined in hemolymph. The ADS was upregulated in workers with age but downregulated in queens. Imidacloprid suppressed the ADS in all workers, particularly in foragers with an upregulated ADS, but it did not affect the ADS in 1-day-old queens. In contrast to foragers, the downregulated ADS of 2-year-old queens was unexpectedly highly upregulated by imidacloprid, which has not been previously shown in such old queens. The principal component analysis confirmed that queen and worker ADSs responded to imidacloprid in opposite ways, and ADS of 2-year-queens was markedly different from those of others. Thus, evolutionary shaped ADSs of older queens and workers may be of the limited use for foragers dwelling in pesticide ecosystems, but not for old queens.

Extracellular Superoxide Dismutase Prevents Skin Aging by Promoting Collagen Production through the Activation of AMPK and Nrf2/HO-1 Cascades

With aging, the skin becomes thin and drastically loses collagen. Extracellular superoxide dismutase (EC-SOD), also known as superoxide dismutase (SOD) 3, is the major SOD in the extracellular matrix of the tissues and is well-known to maintain the reduction‒oxidation homeostasis and matrix components of such tissues. However, the role of EC-SOD in aging-associated reductions of skin thickness and collagen production is not well-studied. In this study, we compared the histological differences in the dorsal skin of EC-SOD‒overexpressing transgenic mice (Sod3^+/+) of different age groups with that in wild-type mice and also determined the underlying signaling mechanism. Our data showed that the skin thickness in Sod3^+/+ mice significantly increased with aging compared with that in wild-type male mice. Furthermore, Sod3^+/+ mice had promoted collagen production through the activation of adenosine monophosphate-activated protein kinase and Nrf2/HO-1 pathways in aged mice. Interestingly, subcutaneous injection of adeno-associated virus‒overexpressing EC-SOD exhibited increased skin thickness and collagen expression. Furthermore, combined recombinant EC-SOD and dihydrotestosterone treatment synergistically elevated collagen production through the activation of TGFβ in human dermal fibroblasts. Altogether, these results showed that EC-SOD prevents skin aging by promoting collagen production in vivo and in vitro. Therefore, we propose that EC-SOD may be a potential therapeutic target for antiaging in the skin.

Pinpointing oxidative stress behind the white striping myopathy: depletion of antioxidant defenses, accretion of oxidized proteins and impaired proteostasis

BACKGROUND

This study aimed to investigate the molecular mechanisms involved in the onset of the white striping (WS) myopathy with particular attention to the role of oxidative stress and protein oxidation in the loss of meat quality.

RESULTS

It was found that WS-M (moderate degree; white stripes <1 mm thickness) and WS-S (severe degree; white stripes >1 mm thickness) breast presented higher pH, hardness, redness, lipid, and collagen content, and lower lightness than normal breast. Compared with the latter, WS-S had a more severe loss of protein thiols (70.7% less thiols than in N), reduced activity of antioxidant enzymes such as catalase (23 versus 40 U g^-1 ), glutathione peroxidase (0.21 versus 0.54 U g^-1 ), and superoxide dismutase (56 versus 73 U g^-1 ), and consequently, had greater accretion of thiobarbituric acid reactive substances (0.64 versus 0.22 mg MDAkg^-1 muscle), allysine (3.1 versus 1.9 nmol mg^-1 protein) and Schiff base structures (645 versus 258 fluorescent units). The analysis of sarcoplasmic proteins revealed that muscles severely affected by the myopathy suffered a chronic impairment of physiological (upregulation of sarcoplasmic reticulum Ca2+ ATPase, sarcalumenin and calsequestrin-2) and metabolic processes (downregulation of pyruvate kinase, creatine kinase, and l-lactate dehydrogenase).

CONCLUSION

The overexpression of ribonuclease / angiogenin inhibitor 1 and Kelch-like proteins in WS chicken breasts indicates altered protein turnover plausibly mediated by oxidative stress and accumulation of oxidized proteins. © 2020 Society of Chemical Industry.

Protective effect of vanillic acid in hydrogen peroxide-induced oxidative stress in D.Mel-2 cell line

The overproduction of reactive oxygen species (ROS) causes oxidative stress, such as Hydrogen peroxide (H2O2). Acute oxidative stress is one of the main reasons for cell death. In this study, the antioxidant properties of vanillic acid- a polyphenolic compound was evaluated. Therefore, this study aims to check the effectiveness of vanillic acid in H2O2-induced oxidative stress in D. Mel-2 cell line. The efficacy was determined by biochemical tests to check the ROS production. The cytotoxicity of H2O2 and vanillic acid was checked by MTT assay. The DNA fragmentation was visualized by gel electrophoresis. Protein biomarkers of oxidative stress were analyzed by western blotting. The results depict a promising antioxidant effect of vanillic acid. The IC50 value of vanillic acid and H2O2 was found 250 μg/ml and 125 μg/ml, respectively. The catalase activity, SOF, GPx, and PC was seen less in H2O2 treated group compared with the control and vanillic acid treated group. However, the TBRAS activity was hight in H2O2 treated group. The effect of H2O2 on DNA fragmentation was high as compared with vanillic acid-treated cells. The protein expression of Hsp70, IL-6 and iNOS was seen significant in a vanillic acid-treated group as compared with H2O2 treated group. These results reinforce that at low concentration, vanillic acid could be used as an antioxidant agent in the food and pharmaceutical industries.