Integrated Transcriptomic and Proteomic Study of the Mechanism of Action of the Novel Small-Molecule Positive Allosteric Modulator 1 in Targeting PAC1-R for the Treatment of D-Gal-Induced Aging Mice.

Small-molecule positive allosteric modulator 1 (SPAM1), which targets pituitary adenylate cyclase-activating polypeptide receptor 1 (PAC1-R), has been found to have a neuroprotective effect, and the underlying mechanism was explored in this study. First, using a D-galactose (D-gal)-induced aging mouse model, we confirmed that SPAM1 improves the structure of the hippocampal dentate gyrus and restores the number of neurons. Compared with D-gal model mice, SPAM1-treated mice showed up-regulated expression of Sirtuin 6 (SIRT6) and Lamin B1 and down-regulated expression of YinYang 1 (YY1) and p16. A similar tendency was observed in senescent RGC-5 cells induced by long-term culture, indicating that SPAM1 exhibits significant in vitro and in vivo anti-senescence activity in neurons. Then, using whole-transcriptome sequencing and proteomic analysis, we further explored the mechanism behind SPAM1's neuroprotective effects and found that SPAM is involved in the longevity-regulating pathway. Finally, the up-regulation of neurofilament light and medium polypeptides indicated by the proteomics results was further confirmed by Western blotting. These results help to lay a pharmacological network foundation for the use of SPAM1 as a potent anti-aging therapeutic drug to combat neurodegeneration with anti-senescence, neuroprotective, and nerve regeneration activity.

An Aloe-Based Composition Constituting Polysaccharides and Polyphenols Protected Mice against D-Galactose-Induced Immunosenescence.

A decline in immune response, exhibited in the form of immunosenescence and inflammaging, is an age-associated disturbance of the immune system known to predispose the elderly to a greater susceptibility to infection and poor vaccine response. Polysaccharides and polyphenols from botanicals are known for their immune modulation effects. Here we evaluated a standardized mushroom-based composition, UP360, from Aloe barbadensis, Poria cocos, and Rosmarinus officinalis, as a natural nutritional supplement for a balanced immune response in an accelerated aging mouse model. Immunosenescence was induced by continual subcutaneous injection of D-galactose (D-gal) at a dose of 500 mg/kg/day to CD-1 mice. UP360 was administered at oral doses of 200 and 400 mg/kg to the mice starting on the 5th week of D-gal injection. The study lasted for a total of 9 weeks. All mice were given a quadrivalent influenza vaccine at 3 µg/animal via intramuscular injection 14 days before the end of the study. A group of D-gal-treated mice treated at 400 mg/kg/day UP360 was kept without vaccination. Whole blood, serum, spleen homogenate, and thymus tissues were used for analysis. UP360 was found to improve the immune response as evidenced by stimulation of innate and adaptive immune responses, increase antioxidant capacity as reflected by augmented SOD and Nrf2, and preserve vital immune organs, such as the thymus, from aging-associated damage. The findings depicted in this report show the effect of the composition in activating and maintaining homeostasis of the immune system both during active infections and as a preventive measure to help prime the immune system. These data warrant further clinical study to explore the potential application of the mushroom-based composition as an adjunct nutritional supplement for a balanced immune response.

Aglycemia induces apoptosis under hypoxic conditions in A549 cells.

Many of the cancer cells produce energy with accelerated glycolysis and perform lactic acid production even under normoxic conditions called the "Warburg effect". Metabolism can directly or indirectly regulate the apoptotic mechanism so that cancer cells take advantage of reprogrammed metabolism to avoid apoptosis. The aim of this study is to examine the mechanism of apoptosis by incubating human lung carcinoma cells (A549) under different metabolic conditions in hypoxia or normoxia environments. A549 cells were incubated in the normoxic or hypoxic condition that contained 5 mM glucose (Glc 5), 25 mM glucose (Glc 25), or 10 mM galactose (OXPHOS/aglycemic), and the mechanism of apoptosis was investigated. In the hypoxia condition, the rate of early apoptosis in aglycemic OXPHOS cells was increased (15.5% ±7.1). In addition, the activity of caspase-3 (6.1% ± 0.9), caspase-9 (30.4% ± 0.9), and cytochrome c expression level increased; however, the mitochondrial membrane potential (51.9% ± 0.4) was found to be decreased. Changing the amount of oxygen in glycolytic cells had no effect on apoptosis. However, it has been determined that apoptosis is stimulated under hypoxia conditions in aglycemic cells in which galactose is used instead of glucose. Considering that the majority of cancer cells are hypoxic, these data are important in determining targets in therapeutic intervention.

Vitamin D Protects Against Cardiac Hypertrophy Through the Regulation of Mitochondrial Function in Aging Rats.

Cardiac aging is defined as mitochondrial dysfunction of the heart. Vitamin D (VitD) is an effective agent in ameliorating cardiovascular disorders. In this study, we indicated the protective effects of VitD against cardiac aging. Male Wistar rats were randomly divided into four groups: control (CONT), D-galactose (D-GAL): aged rats induced by D-GAL, D-GAL + Ethanol: aged rats treated with ethanol, and D-GAL + VitD aged rats treated with VitD. Aging was induced by D-GAL at 150 mg/kg via intraperitoneal injection for 8 weeks. Aged rats were treated with VitD (D-GAL + VitD) by gavage for 8 weeks. The serum samples were used to evaluate biochemical factors, and heart tissues were assessed to determine oxidative stress and gene expression. The D-GAL rats exhibited cardiac hypertrophy, which was associated with decreased antioxidant enzyme activity, enhanced oxidative marker, and changes in the expression of mitochondrial genes in comparison with the control rats. Co-treatment with VitD ameliorated all these changes. In conclusion, VitD could protect the heart against D-GAL-induced aging via enhancing antioxidant effects, and the expression of mitochondrial genes.

Selenium- and/or Zinc-Enriched Egg Diet Improves Oxidative Damage and Regulates Gut Microbiota in D-Gal-Induced Aging Mice.

Eggs, with their high nutritional value, are great carriers for enriching nutrients. In this study, selenium- and/or zinc-enriched eggs (SZE) were obtained and their effects on ameliorating oxidative stress injury, alleviating cognitive impairment, and maintaining intestinal flora balance in a D-gal-induced aging mice model were investigated. As determined by the Y-maze test, SZE restored the learning and memory abilities and increased the Ach level and AChE activity of aging mice (p < 0.05). Meanwhile, supplementation of low-dose SZE increased antioxidant levels and decreased inflammation levels (p < 0.05). High-dose SZE increased anti-inflammatory levels but were less effective than low dose. Additionally, SZE maintained the intestinal flora balance and significantly increased the ratio of Firmicutes and Bacteroidota. Blautia, as a probiotic, was negatively correlated with pro-inflammatory factors and positively correlated with antioxidant levels (p < 0.05). These results suggest that SZE might improve organ damage and cognitive function by attenuating oxidative stress and inflammatory response and maintaining healthy gut flora.

LAMMER Kinase Governs the Expression and Cellular Localization of Gas2, a Key Regulator of Flocculation in Schizosaccharomyces pombe.

It was reported that LAMMER kinase in Schizosaccharomyces pombe plays an important role in cation-dependent and galactose-specific flocculation. Analogous to other flocculating yeasts, when cell wall extracts of the Δlkh1 strain were treated to the wild-type strain, it displayed flocculation. Gas2, a 1,3-ß-glucanosyl transferase, was isolated from the EDTA-extracted cell-surface proteins in the Δlkh1 strain. While disruption of the gas2+ gene was not lethal and reduced the flocculation activity of the ∆lkh1 strain, the expression of a secreted form of Gas2, in which the GPI anchor addition sequences had been removed, conferred the ability to flocculate upon the WT strain. The Gas2-mediated flocculation was strongly inhibited by galactose but not by glucose. Immunostaining analysis showed that the cell surface localization of Gas2 was crucial for the flocculation of fission yeast. In addition, we identified the regulation of mbx2+ expression by Lkh1 using RT-qPCR. Taken together, we found that Lkh1 induces asexual flocculation by regulating not only the localization of Gas2 but also the transcription of gas2+ through Mbx2.

D-galactose might mediate some of the skeletal muscle hypertrophy-promoting effects of milk-A nutrient to consider for sarcopenia?

Sarcopenia is a process of progressive aging-associated loss of skeletal muscle mass (SMM) recognized as a serious global health issue contributing to frailty and increased all-cause mortality. Exercise and nutritional interventions (particularly intake of dairy products and milk) demonstrate good efficacy, safety, and broad applicability. Here, we propose that at least some of the well-documented favorable effects of milk and milk-derived protein supplements on SMM might be mediated by D-galactose, a monosaccharide present in large quantities in milk in the form of disaccharide lactose (milk sugar). We suggest that ingestion of dairy products results in exposure to D-galactose in concentrations metabolized primarily via the Leloir pathway with the potential to (i) promote anabolic signaling via maintenance of growth factor (e.g., insulin-like growth factor 1 [IGF-1]) receptor mature glycosylation patterns; and (ii) provide extracellular (liver glycogen) and intracellular substrates for short (muscle glycolysis) and long-term (muscle glycogen, intramyocellular lipids) energy availability. Additionally, D-galactose might optimize the metabolic function of skeletal muscles by increasing mitochondrial content and stimulating glucose and fatty acid utilization. The proposed potential of D-galactose to promote the accretion of SMM is discussed in the context of its therapeutic potential in sarcopenia.

d-Galactose induces the senescence and phenotype switch of corpus cavernosum smooth muscle cells.

Studies regarding age-related erectile dysfunction (ED) based on naturally aging models are limited by their high costs, especially for the acquisition of primary cells from the corpus cavernosum. Herein, d-galactose ( d-gal) was employed to accelerate cell senescence, and the underlying mechanism was explored. As predominant functional cells involved in the erectile response, corpus cavernosum smooth muscle cells (CCSMCs) were isolated from 2-month-old rats. Following this, d-gal was introduced to induce cell senescence, which was verified via ß-galactosidase staining. The effects of d-gal on CCSMCs were evaluated by terminal deoxynucleoitidyl transferase dUTP nick-end labeling (TUNEL), immunofluorescence staining, flow cytometry, western blot, and quantitative real-time polymerase chain reaction (qRT-PCR). Furthermore, RNA interference (RNAi) was carried out for rescue experiments. Subsequently, the influence of senescence on the corpus cavernosum was determined via scanning electron microscopy, qRT-PCR, immunohistochemistry, TUNEL, and Masson stainings. The results revealed that the accelerated senescence of CCSMCs was promoted by d-gal. Simultaneously, smooth muscle alpha-actin (alpha-SMA) expression was inhibited, while that of osteopontin (OPN) and Krüppel-like factor 4 (KLF4), as well as fibrotic and apoptotic levels, were elevated. After knocking down KLF4 expression in d-gal-induced CCSMCs by RNAi, the expression level of cellular alpha-SMA increased. Contrastingly, the OPN expression, apoptotic and fibrotic levels declined. In addition, cellular senescence acquired partial remission. Accordingly, in the aged corpus cavernosum, the fibrotic and apoptotic rates were increased, followed by downregulation in the expression of alpha-SMA and the concurrent upregulation in the expression of OPN and KLF4. Overall, our results signaled that d-gal-induced accelerated senescence of CCSMCs could trigger fibrosis, apoptosis and phenotypic switch to the synthetic state, potentially attributed to the upregulation of KLF4 expression, which may be a multipotential therapeutic target of age-related ED.

Synergistic effects of MFG-E8 and whey protein on mitigating d-galactose-induced sarcopenia through PI3K/AKT/PGC-1α and MAPK/ERK signaling pathways.

Milk fat globule epidermal growth factor 8 (MFG-E8) and whey protein have emerged as promising bionutrient supplements for enhancing skeletal muscle mass and function. In the present study, aging-related sarcopenia rat model was employed to elucidate the effects of the combined administration of MFG-E8 and whey protein on the catabolism and anabolism of gastrocnemius protein. Combined intervention led to notable enhancements in the antioxidative stress status and mitochondrial biogenesis capacity of gastrocnemius muscle fibers in the aging rats, concomitant with a significant inhibition of lipid accumulation. Moreover, the synergistic effect of MFG-E8 and whey protein was found to exert modulatory effects on key signaling pathways, including PI3K/Akt/PGC-1α pathway and MAPK/ERK signaling pathways in the gastrocnemius muscle of the aging rats. Specifically, this combined intervention was observed to promote mitochondrial biogenesis and regulate the expression of protein anabolism and catabolism-related regulators, thereby facilitating the alleviation of mitochondrial oxidative stress and enhancing biogenesis in gastrocnemius tissues. The findings of our study provide compelling evidence for the potential of MFG-E8 as a promising dietary supplement with antisarcopenic properties to ameliorate muscle protein metabolism disorders and mitigate mitochondrial-mediated myoblast apoptosis induced by oxidative stress.

Ginseng promotes the function of intestinal stem cells through the Wnt/ß-catenin signaling pathway in D-galactose-induced aging mice.

BACKGROUND: Intestinal stem cells (ISCs) are the reservoir source of various types of intestinal cells, and the decline of stem cell function in the gut may be a potential factor for aging-related disease. The present study aimed to explore the regulatory mechanisms of Panax ginseng C.A.Meyer (Araliaceae, Panax genus) that could restore gut aging by enhancing intestinal function and regulating ISCs in aging mice based on the Wnt/ß-catenin signaling pathway. METHODS: A total of 60 ICR male mice were randomly divided into control, model, metformin, and ginseng water decoction (GWD) 3.6, 1.8, and 0.9 g/kg groups. The aging model was induced by 1 % D-galactose (s.c. 0.1 mL/10 g) for 28 days. Moreover, GWD was given to aging mice intragastrically (i.g.) once a day for 28 successive days. The learning memory ability, pathological status, and function in the ileum tissue, the activity of digestive enzymes, and short-chain fatty acid (SCFA) content in the colon were evaluated, and the related mechanism was investigated. RESULTS: Ginseng can decrease the escape latency time and increase the swimming speed and the number of crossing platforms in aging mice. Moreover, the pathology of ileum tissue improved, the length of the intestinal villi increased, and the width of the villi and the depth of the crypts decreased. The activities of trypsin, α-amylase, and lipase increased in duodenal content and intestinal mucosa. In the colon, the content of SCFA, such as acetic acid, propionic acid and butyric acid, increased, indicating that ginseng significantly improves intestinal function impairment. The mRNA expressions and protein levels of ß-catenin, C-myc, GSK-3ß, Lgr5, and Olfm4 were upregulated in the ginseng group. CONCLUSIONS: Ginseng improves intestinal function and regulates the function of ISCs in order to protect intestinal health by activating the Wnt/ß-catenin signaling pathway in aging mice.

The effects of galacto-oligosaccharides on faecal parameters in healthy dogs and cats.

The aim of this study was to evaluate the effects of galacto-oligosaccharides (GOS) on faecal parameters in healthy dogs and cats. To this end, 20 dogs and 20 Domestic shorthair cats were fed a commercially available adult dog food, or cat food, respectively, with either syrup containing GOS (at 1% w galacto-oligosaccharides/w formulated feed) on top (test group) or no topping (control group) for 56 days in a cross-over design. The study consisted of 2 periods of 24 days adaptation, followed by 4 days of collection of faeces. Faecal samples were tested for moisture, nitrogen, pH, macronutrients, enzymes, and fermentation products. The faecal microbiota were analysed by 16S rDNA profiling. It appeared that GOS have different effects in dogs compared to cats. In dogs, the addition of GOS resulted in increased carbohydrate fermentation (increase of acetic and butyric acid), whereas in cats GOS resulted in increased amino acid fermentation (increase of isovaleric acid). The α-diversity of the canine faecal microbiota was reduced by dietary GOS (Inverse Simpson Index, p = 0.063; Shannon index, p = 0.035) whereas the α-diversity of cat faecal microbiota was unaffected (Inverse Simpson Index, p = 0.539; Shannon index, p = 0.872). Lachnospiraceae spp. and Bifidobacterium spp. positively responded to GOS in both cats and dogs. Lactobacillus spp. and Enterobacteriaceae spp. positively responded to GOS in dogs. In both dogs and cats, GOS may therefore improve stool microbiota and result in the production of specific metabolites that are beneficial to gut health.

Differential metabolites screening in yak (Bos grunniens) seminal plasma after cryopreservation and the evaluation of the effect of galactose on post-thaw sperm motility.

Sperm survival and activity depend on the provision of energy and nutrients from seminal plasma (SP). This study aimed to investigate the variations of metabolites within SP before and after freezing and subsequently explore the potential regulatory mechanisms affecting yak sperm cryodamage due to changes in metabolites in the SP. Untargeted metabolomics analysis was performed to screen for differential metabolites, followed by KEGG analysis to identify enriched signaling pathways. The combinatorial analysis of metabolomics and sperm proteomics revealed the influence of key SP metabolites on sperm proteins. Subsequently, the relevant differentially expressed proteins were verified by Western blot analysis. Finally, the mechanism underlying the positive effect of galactose on sperm motility was determined by assessing the change in ATP content in sperm before and after freezing and thawing. The data showed that a total of 425 and 269 metabolites were identified in the positive and negative ion modes, respectively. Freezing and thawing resulted in the up-regulation of 70 metabolites and the down-regulation of 29 metabolites in SP. The primary impact of freezing and thawing was observed in carbohydrate metabolism, including pyruvate metabolism, pentose phosphate pathway, galactose metabolism, the TCA cycle, and butanoate metabolism. In the combined analysis and Western blot results, a significant positive correlation was observed between galactose and Aldo-keto reductase family 1 member B1 (AKR1B1) (P < 0.05), which has the ability to convert galactose into galactol. Furthermore, the addition of galactose to thawed semen improved sperm motility by increasing AKR1B1 protein in sperm and was associated with the content of ATP. These data identify differential metabolites between fresh and frozen-thawed SP and suggest that galactose is a valuable additive for cryopreserved sperm, providing a theoretical basis for further exploration of the refrigerant formula for yak sperm cryopreservation.

Purification, biochemical characterization of a lectin from marine sponge Ircinia strobilina and its effect on the inhibition of bacterial biofilms.

A new lectin from marine sponge Ircinia strobilina, denominated IsL, was isolated by combination of affinity chromatography in Guar gum matrix followed by size exclusion chromatography. IsL was able to agglutinate native and enzymatically treated rabbit erythrocytes, being inhibited by galactosides, such as α-methyl-D-galactopyranoside, ß-methyl-D-galactopyranoside and α-lactose. IsL hemagglutinating activity was stable at neutral to alkaline pH, however the lectin loses its activity at 40° C. The molecular mass determinated by mass spectrometry was 13.655 ± 5 Da. Approximately 40% of the primary structure of IsL was determined by mass spectrometry, but no similarity was observed with any protein. The secondary structure of IsL consists of 28% α-helix, 26% ß-sheet, and 46% random region, as determined by dichroism circular. IsL was a calcium-dependent lectin, but no significant variations were observed by circular dichroism when IsL was incubated in presence of calcium and EDTA. IsL was not toxic against Artemia nauplii and did not have antimicrobial activity against bacterial cells. However, the IsL was able to significantly inhibit the biofilm formation of Staphylococcus aureus and Staphylococcus epidermidis.

Long-term lifestyle intervention is superior to transient modification for neuroprotection in D-galactose-induced aging rats.

AIMS: To investigate whether transient dietary restriction or aerobic exercise in young adulthood exert long-lasting protection against brain aging later in life. MAIN METHODS: Seven-week-old male Wistar rats were divided into 2 groups and given either normal saline as a vehicle (n = 8) or 150 mg/kg/day of D-galactose (n = 40) for 28 weeks, the D-galactose being used to induce aging. At week 13 of the experiment, D-galactose-treated rats were further divided into 5 groups, 1) no intervention, 2) transient dietary restriction for 6 weeks (week 13-18), 3) transient exercise for 6 weeks (week 13-18), 4) long-term dietary restriction for 16 weeks (week 13-28), and 5) long-term exercise for 16 weeks (week 13-28). At the end of week 28, cognitive function was examined, followed by molecular studies in the hippocampus. KEY FINDINGS: Our results showed that either long-term dietary restriction or aerobic exercise effectively attenuated cognitive function in D-galactose-treated rats via the attenuation of oxidative stress, cellular senescence, Alzheimer's-like pathology, neuroinflammation, and improvements in mitochondria, brain metabolism, adult neurogenesis, and synaptic integrity. Although transient interventions provided benefits in some brain parameters in D-galactose-treated rats, an improvement in cognitive function was not observed. SIGNIFICANCE: Our findings suggested that transient lifestyle interventions failed to exert a long-lasting protective effect against brain aging. Hence, novel drugs mimicking the neuroprotective effect of long-term dietary restriction or exercise and the combination of the two since young age appear to be more appropriate treatments for the elderly who are unable to engage in long-term dietary restriction or exercise.

The Ethanolic Extract of Lycium ruthenicum Ameliorates Age-Related Physiological Damage in Mice.

Aging and age-related diseases are important study topics due to their associations with progressive physiological damage to genes, cells, tissues, and the entire organism, which ultimately affects the functional efficiency of organs. Lycium ruthenicum Murr. is a functional food that is known for its high contents of anthocyanins and spermidines, both of which have been demonstrated to have positive effects on anti-aging activity and anti-oxidation. In this study, we used HPLC-MS to analyze the constituents of L. ruthenicum Murr. Extract (LRM) and investigated their potential mechanism for exerting antioxidative effects in D-galactose (D-Gal) aging model mice. LRM (25 mg/kg, 50 mg/kg, and 100 mg/kg) improved cognitive function in D-Gal-treated mice, as shown by reduced escape latencies and increased platform crossings in behavioral tests. We measured the contents of lipid peroxidation (LPO) and malondialdehyde (MDA) and the enzyme activities of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in mice serum and brain after 6 weeks of D-Gal treatment. LRM decreased the contents of LPO and MDA and increased the enzyme activities of SOD and GSH-Px, indicating the protection effect of LRM against D-Gal-induced oxidative stress. Additionally, LRM can inhibit oxidative stress in cells by reducing intracellular ROS levels and restoring mitochondrial membrane potential, thereby inhibiting paraquat (PQ)-induced cellular senescence and delaying cell aging. Therefore, LRM has the potential to be a healthcare product for the treatment of age-related diseases.

Aerobic Treadmill Exercise Upregulates Epidermal Growth Factor Levels and Improves Learning and Memory in d-galactose-Induced Aging in a Mouse Model.

Previous studies have demonstrated that exercise improves cognitive function in Alzheimer's disease mice but the exact mechanism needs further studies. This research aimed to study the effects of aerobic treadmill exercise on epidermal growth factor (EGF) levels and learning and memory in d-galactose-induced aging in a mouse model. Forty male Kunming mice were analyzed in this study and randomly divided into 4 groups: control (C group), aerobic exercise (AE group), d-galactose (D-gal group), and d-galactose + aerobic exercise (D-gal + AE group). The C and AE groups received a daily mid-scapular subcutaneous injection of .9% saline for 40 days. Mice in the D-gal and D-gal + AE groups were subcutaneously injected with d-galactose (1.25 mg/kg) once daily for 40 days. The mice in the AE group and D-gal + AE group completed 40 days of aerobic treadmill exercise. Learning and memory were evaluated by step-down tests. Specifically, 24 h after the behavioral test, blood was collected and brain tissue was extracted, and superoxide dismutase (SOD) and acetylcholinesterase activities were detected. The neurons in the CA1 and CA3 regions of the hippocampus were counted by Nissl staining. The number of EGF-positive cells was observed by immunohistochemical methods. In the learning test, the reaction time in the D-gal group increased significantly (P < .05), while the error numbers in the D-gal group tended to decrease compared with AE, D-gal + AE, and C groups. In the memory test, the latency of mice in the D-gal group was lower, while the error in this group was higher than in the other groups (P < .05). The activities of SOD and acetylcholinesterase were lower in the D-gal group than in the other groups (P < .05). The number of EGF-positive cells and neurons in the hippocampal CA1 and CA3 regions in the D-gal + AE group was higher compared to those in the D-gal group (P < .05), and lower in groups with mice that were not injected with d-galactose. Aerobic treadmill exercise inhibited SOD activity, increased EGF-positive cells, and decreased neuronal death and apoptosis, thereby improving learning and memory in the mouse model of d-galactose-induced aging.

IGF2 deficiency promotes liver aging through mitochondrial dysfunction and upregulated CEBPB signaling in D-galactose-induced aging mice.

BACKGROUND: Liver aging, marked by cellular senescence and low-grade inflammation, heightens susceptibility to chronic liver disease and worsens its prognosis. Insulin-like growth factor 2 (IGF2) has been implicated in numerous aging-related diseases. Nevertheless, its role and underlying molecular mechanisms in liver aging remain largely unexplored. METHODS: The expression of IGF2 was examined in the liver of young (2-4 months), middle-aged (9-12 months), and old (24-26 months) C57BL/6 mice. In vivo, we used transgenic IGF2f/f; Alb-Cre mice and D-galactose-induced aging model to explore the role of IGF2 in liver aging. In vitro, we used specific short hairpin RNA against IGF2 to knock down IGF2 in AML12 cells. D-galactose and hydrogen peroxide treatment were used to induce AML12 cell senescence. RESULTS: We observed a significant reduction of IGF2 levels in the livers of aged mice. Subsequently, we demonstrated that IGF2 deficiency promoted senescence phenotypes and senescence-associated secretory phenotypes (SASPs), both in vitro and in vivo aging models. Moreover, IGF2 deficiency impaired mitochondrial function, reducing mitochondrial respiratory capacity, mitochondrial membrane potential, and nicotinamide adenine dinucleotide (NAD)+/NADH ratio, increasing intracellular and mitochondrial reactive oxygen species levels, and disrupting mitochondrial membrane structure. Additionally, IGF2 deficiency markedly upregulated CCAAT/enhancer-binding protein beta (CEBPB). Notably, inhibiting CEBPB reversed the senescence phenotypes and reduced SASPs induced by IGF2 deficiency. CONCLUSIONS: In summary, our findings strongly suggest that IGF2 deficiency promotes liver aging through mitochondrial dysfunction and upregulated CEBPB signaling. These results provide compelling evidence for considering IGF2 as a potential target for interventions aimed at slowing down the process of liver aging.

Exploratory Study of Gastrointestinal Redox Biomarkers in the Presymptomatic and Symptomatic Tg2576 Mouse Model of Familial Alzheimer's Disease: Phenotypic Correlates and Effects of Chronic Oral d-Galactose.

The gut might play an important role in the etiopathogenesis of Alzheimer's disease (AD) as gastrointestinal alterations often precede the development of neuropathological changes in the brain and correlate with disease progression in animal models. The gut has an immense capacity to generate free radicals whose role in the etiopathogenesis of AD is well-known; however, it remains to be clarified whether gastrointestinal redox homeostasis is associated with the development of AD. The aim was to (i) examine gastrointestinal redox homeostasis in the presymptomatic and symptomatic Tg2576 mouse model of AD; (ii) investigate the effects of oral d-galactose previously shown to alleviate cognitive deficits and metabolic changes in animal models of AD and reduce gastrointestinal oxidative stress; and (iii) investigate the association between gastrointestinal redox biomarkers and behavioral alterations in Tg2576 mice. In the presymptomatic stage, Tg2576 mice displayed an increased gastrointestinal electrophilic tone, characterized by higher lipid peroxidation and elevated Mn/Fe-SOD activity. In the symptomatic stage, these alterations are rectified, but the total antioxidant capacity is decreased. Chronic oral d-galactose increased the antioxidant capacity and reduced lipid peroxidation in the Tg2576 but had the opposite effects in the wild-type animals. The total antioxidant capacity of the gastrointestinal tract was associated with greater spatial memory. Gut redox homeostasis might be involved in the development and progression of AD pathophysiology and should be further explored in this context.

Effect of vitamin D on cardiac hypertrophy in D-galactose-induced aging model through cardiac mitophagy.

BACKGROUND: Cardiac apoptosis plays a key role in increased morbidity associated with aging-induced-cardiac disorder. Mitochondria play an important role in cardiac apoptosis, and dynamin-related protein 1 (Drp1), as a main mediator of mitochondrial fission, can trigger the mitophagy process to sustain the mitochondrial quality. The present study was done to determine the effect of vitamin D (VitD) treatment on cardiac hypertrophy through mitophagy regulation in aged animals induced by D-galactose (D-GAL). METHODS AND RESULTS: Male Wistar rats were randomly divided into four groups: control, D-GAL (aging group), D-GAL co-injected with VitD (D-GAL ± VitD), and D-GAL plus ethanol (D-GAL ± Ethanol). Aging was induced by an intraperitoneal (i.p.) administration of D-GAL at 150 mg/kg daily for eight weeks and also VitD (400 IU/kg) or ethanol was injected (i.p.) into aging rats. Then, the levels of cardiac mitophagy and cardiac apoptosis were determined by measuring the expression of tensin homologue (PTEN)-induced putative kinase 1 (PINK1), Drp1, Bcl2-Associated X (Bax), and B-cell lymphoma 2 (Bcl2) genes. Aging in rats was associated with a reduction in mitophagy and also an increase in apoptosis of the heart through down-regulation of Drp1, PINK1, and Bcl2 genes and also up-regulation of Bax. However, VitD improved cardiac hypertrophy through cardiac mitophagy in D-GAL-induced aging rats. CONCLUSION: VitD can inhibit cardiac hypertrophy by an increase in mitophagy and a decrease in apoptosis in the aging heart. The illustration of the suggested mechanism underlying of Vitamin D in cardiac hypertrophy induced by aging.

Effect of lidocaine on cognitively impaired rats: Anti-inflammatory and antioxidant mechanisms in combination with CRMP2 antiphosphorylation.

OBJECTIVE: Studies have shown that lidocaine has antioxidative stress, anti-inflammatory, and nerve-protective effects. The current study investigated the effects of lidocaine on cognitive function in rats with cognitive dysfunction. METHODS: A total of 48 rats were randomly assigned to four groups of 12 rats each: control group; L (lidocaine) + D (d-galactose) group, d-galactose group (D group); and D + L group. We assessed cognitive function using a Morris water maze (MWM) and pathologic changes of hippocampal sections. An enzyme-linked immunosorbent assay (ELIZA) was used to detect serum malondialdehyde (MDA) and superoxide dismutase (SOD) levels in rats, and protein immunoblotting (western blot) was used to detect brain tissue proteins (collapsing response mediator protein-2 [CRMP2], phosphorylated-collapsing response mediator protein-2 [P-CRMP2], and ß-amyloid protein [Aß]). RESULTS: The MWM showed that the d-gal group (284.09 ± 20.46, 5.20 ± 0.793) performed worse than the L + D (265.37 ± 22.34, 4.170 ± 0.577; p = .000) and D + L groups (254.72 ± 27.87, 3.750; p = .000) in escape latency and number of platform crossings, respectively. The L + D group (44.94 ± 2.92 pg/mL, 6.22 ± 0.50 pg/mL, and 460.02 ± 8.26 nmol/mL) and D + L group (46.88 ± 2.63 pg/mL, 5.90 ± 0.38 pg/mL, and 465.6 ± 16.07 nmol/mL) had significantly lower serum inflammatory levels of interleukin-6, tumor necrosis factor-α, and MDA than the d-gal group (57.79 ± 3.96 pg/mL, 11.25 ± 1.70 pg/mL, and 564.9 ± 15.90 nmol/mL), respectively. The L + D group (3.17 ± 0.41 µg/mL) and D + L group (3.08 ± 0.09 µg/mL) had significantly higher serum inflammatory levels of SOD than the d-gal group (2.20 ± 0.13 µg/mL) (all p = .000). The levels of CRMP2, P-CRMP2, and Aß in the brain tissue homogenates of the L + D group (0.87 ± 0.04, 0.57 ± 0.0, and 0.16 ± 0.02) and the D + L group (0.82 ± 0.05, 0.58 ± 0.09, and 0.15 ± 0.02) were significantly different than the d-gal group (0.67 ± 0.03, 0.96 ± 0.040, and 0.29 ± 0.05). CONCLUSIONS: Lidocaine was shown to reduce cognitive impairment in rats with cognitive dysfunction through anti-inflammatory and antioxidative stress mechanisms in combination with CRMP2 antiphosphorylation.