Hesperidin Supplementation Improves Altered PON -1, LDL Oxidation, Inflammatory Response and Hepatic Function in an Experimental Rat Model of Hyperlipidemia

In this study, we have examined the effect of hesperidin on rats fed on an experimental high-fat diet. Male Wistar rats were given a high-fat diet orally for one month for developing an HFD (High fat- diet) model. Rats were also supplemented with hesperidin (100 mg/kg body weight) for one month. We determined serum LDL (Low-density lipoprotein) oxidation, Paraoxonase-1 (PON-1) activity, and histopathological profile of the liver. Inflammatory cytokines levels were also measured in serum. HFD induced significant changes in LDL oxidation and PON-1 activity. Liver tissue histopathology and gene expression of inflammatory markers (Il-6(Interleukin-6), TNF- alpha (Tumor necrosis factor alpha), NF-KB (Nuclear factor kappa B) show that significant changes occur in the hyperlipidemic model of rats. We also show that hesperidin can effectively improve plasma antioxidant, LDL oxidation, and inflammatory cytokine expression in rats already subjected to hyperlipidemic stress. We conclude that hesperidin may protect the liver from oxidative stress by improving hepatic function.

Monosodium Glutamate Even at Low Dose May Affect Oxidative Stress, Inflammation and Neurodegeneration in Rats

Monosodium glutamate (MSG) is a widely used flavour enhancer. A daily intake of MSG at high dosage (2000-4000 mg/kg body weight) is reported to be toxic to humans and experimental animals. The present study aims to investigate the toxic effect of oral administration of MSG at low concentrations (30 and 100 mg/kg body weight) by evaluating biochemical parameters of oxidative stress and inflammation in blood; expression of neuroinflammatory gene and histopathological changes in brain on male Wistar rats. The administration of MSG significantly increases serum level of fasting glucose, insulin, triglycerides, total cholesterol, low-density lipoprotein and decrease level of high-density lipoprotein. Significant low level of FRAP, GSH, SOD, CAT and higher level of MDA, PCO, AOPP, PMRS, NO, CRP, IL-6, TNF-α confirms substantial oxidative stress followed by inflammation after 100 mg MSG treatment. RT-PCR figure shows significant expression of neuroinflammatory gene IL-6 and TNF-α and histopathological examination revealed severe neurodegeneration in hippocampus (CA1 and CA3) and cerebral cortex region of brain at 100 mg MSG treatment. Our result provides evidence that MSG administration at 30 mg does not impose toxicity, however at 100 mg/kg body weight, which is considered a low dose, there is significant toxic effects and may be detrimental to health.

Crosstalk Between Aging, Circadian Rhythm, and Melatonin

Circadian rhythms (CRs) are 24-hour periodic oscillations governed by an endogenous circadian pacemaker located in the suprachiasmatic nucleus (SCN), which organizes the physiology and behavior of organisms. Circadian rhythm disruption (CRD) is also indicative of the aging process. In mammals, melatonin is primarily synthesized in the pineal gland and participates in a variety of multifaceted intracellular signaling networks and has been shown to synchronize CRs. Endogenous melatonin synthesis and its release tend to decrease progressively with advancing age. Older individuals experience frequent CR disruption, which hastens the process of aging. A profound understanding of the relationship between CRs and aging has the potential to improve existing treatments and facilitate development of novel chronotherapies that target age-related disorders. This review article aims to examine the circadian regulatory mechanisms in which melatonin plays a key role in signaling. We describe the basic architecture of the molecular circadian clock and its functional decline with age in detail. Furthermore, we discuss the role of melatonin in regulation of the circadian pacemaker and redox homeostasis during aging. Moreover, we also discuss the protective effect of exogenous melatonin supplementation in age-dependent CR disruption, which sheds light on this pleiotropic molecule and how it can be used as an effective chronotherapeutic medicine.

Vitamin C Improves Inflammatory-related Redox Status in Hyperlipidemic Rats

Excessive dietary fat is mainly responsible for metabolic diseases including atherosclerosis and cardiovascular disease. We have evaluated the role of Vitamin C in an experimental hyperlipidemic model of rats (male Wistar rat 12-16 months). The hyperlipidemic model of the rat was created by treatment with an atherogenic suspension: cholesterol, cholic acid, and coconut oil, for 30 days once daily, and supplemented with Vitamin C (Ascorbic acid) doses of 0.5 g/kg body weight (orally) for the 30 days once daily. Bodyweight, fasting glucose, triglyceride, cholesterol, ROS (Reactive oxygen species), MDA (Malondialdehyde), FRAP (Ferric reducing the ability of plasma), GSH (Reduced glutathione), PCO (Protein carbonyl), PON-1(Paraoxonase-1), AGE (Advanced glycation end product), PMRS (Plasma membrane reduced system), and inflammatory cytokines (TNF-α and IL-6) were estimated in blood and plasma. Our result shows that oxidative stress, and inflammatory markers, were increased in the HFD-treated group of rats. Vitamin C supplementation protected against lipidemic and, oxidative stress. We conclude that Vitamin C may be useful in maintaining cellular redox balance and protecting against lipidemic stress.

Acarbose Mitigates Age-Dependent Alterations in Erythrocyte Membrane Transporters During Aging in Rats

Acarbose (ACA), a well-studied and effective inhibitor of α-amylase and α-glucosidase, is a postprandial-acting antidiabetic medicine. The membrane of the erythrocyte is an excellent tool for analyzing different physiological and biochemical activities since it experiences a range of metabolic alterations throughout aging. It is uncertain if ACA modulates erythrocyte membrane activities in an age-dependent manner. As a result, the current study was conducted to explore the influence of ACA on age-dependent deteriorated functions of transporters/exchangers, disrupted levels of various biomarkers such as lipid hydroperoxides (LHs), protein carbonyl (PCO), sialic acid (SA), total thiol (-SH), and erythrocyte membrane osmotic fragility. In addition to a concurrent increase in Na+/H+ exchanger activity and concentration of LH, PCO, and osmotic fragility, we also detected a considerable decrease in membrane-linked activities of Ca2+-ATPase (PMCA) and Na+/K+-ATPase (NKA), as well as concentrations of SA and -SH in old-aged rats. The aging-induced impairment of the activities of membrane-bound ATPases and the changed levels of redox biomarkers were shown to be effectively restored by ACA treatment.

Berberine may provide redox homeostasis during aging in rats

Aging is a natural phenomenon, which is characterised by progressive physiological changes at cellular and organ level. During aging, the defence mechanism of an organism declines over the period of time. The aim of this study was to investigate the biological efficacy of berberine in D-galactose induced aging rat models. For the study, rats were divided into four groups: Control received only vehicle, BBR received berberine orally, D-Gal received D-galactose subcutaneously and BBR + D-Gal received D-galactose and berberine simultaneously. D-galactose treatment increased the pro-oxidants such as malondialdehyde (MDA) level, protein carbonyl, plasma membrane redox system (PMRS) and advanced oxidation protein products (AOPP) in the erythrocytes or plasma. It reduced the anti-oxidant level such as reduced glutathione (GSH), ferric reducing ability of plasma (FRAP), plasma thiols, sialic acid and membrane transporters like Na+/K+ ATPase and Ca2+ ATPase activity in the erythrocyte membrane. Co-treatment of berberine in D-galactose induced aging rat models restored pro-oxidants and anti-oxidants in erythrocytes. Berberine also restored the activity of Na+/K+ ATPase and Ca2+ ATPase in the erythrocyte membrane. On the basis of these findings, we suggest that berberine treatment could attenuate erythrocyte aging in rats through stabilisation of the redox equilibrium.

Curcumin displays a potent caloric restriction mimetic effect in an accelerated senescent model of rat

Curcumin, a strong natural compound with numerous health benefits, is extracted from the Curcuma longa. According to recent research findings, it also acts as a calorie restriction mimetic. We examined established aging biomarkers in erythrocytes and plasma and tested a persistent oral dietary dose of curcumin in young and D-galactose-induced accelerated rat aging models. For four weeks, D-gal (300 mg/kg b.w. subcutaneously) and curcumin (200 mg/kg b.w. oral) were administered simultaneously to test the protective effects of curcumin against D-galactose-induced accelerated aging and oxidative stress. In the accelerated senescent rat model, we discovered a significant rise in protein carbonyl, malonaldehyde (MDA), and advanced oxidation protein products. Increased levels of catalase, superoxide dismutase, ferric-reducing antioxidant potential, and reduced glutathione (GSH) were observed. Our findings reveal that curcumin has characteristics resembling a calorie restriction mimic and can successfully maintain redox equilibrium throughout the aging process in rat erythrocytes and plasma.

3-Bromopyruvate elevates ROS and induces hormesis to exert a caloric restriction mimetic effect in young and old rats

CONTEXT

3-Bromopyruvate (3-BP) is a glycolytic inhibitor and a putative caloric restriction mimetic.

OBJECTIVE

We have examined the effect of low-dose administration of 3-BP to rats and assess the CRM effect by measuring an array of biomarkers of oxidative stress.

MATERIALS AND METHODS

Male Wistar young and old rats were administered with a low-dose 3-BP for four weeks.

RESULTS

A significant increase in ROS was observed in 3-BP-treated rats (both young and old), an increase in erythrocyte PMRS (plasma membrane redox system), FRAP (Ferric reducing ability of plasma), catalase and superoxide dismutase activities were also observed. Treatment with 3-BP also reduced protein carbonyl, advanced oxidation protein products, plasma sialic acid, and advanced glycation end products.

CONCLUSION

Short-term 3-BP treatment can provide protection against oxidant stress. We suggest that 3-BP triggers a hormetic response subsequent to an increase in ROS leading to the induction of a protective defense mechanism.

Therapeutic potential of melatonin and its derivatives in aging and neurodegenerative diseases

Aging is associated with increasing impairments in brain homeostasis and represents the main risk factor across most neurodegenerative disorders. Melatonin, a neuroendocrine hormone that regulates mammalian chronobiology and endocrine functions is well known for its antioxidant potential, exhibiting both cytoprotective and chronobiotic abilities. Age-related decline of melatonin disrupting mitochondrial homeostasis and cytosolic DNA-mediated inflammatory reactions in neurons is a major contributory factor in the emergence of neurological abnormalities. There is scattered literature on the possible use of melatonin against neurodegenerative mechanisms in the aging process and its associated diseases. We have searched PUBMED with many combinations of key words for available literature spanning two decades. Based on the vast number of experimental papers, we hereby review recent advancements concerning the potential impact of melatonin on cellular redox balance and mitochondrial dynamics in the context of neurodegeneration. Next, we discuss a broader explanation of the involvement of disrupted redox homeostasis in the pathophysiology of age-related diseases and its connection to circadian mechanisms. Our effort may result in the discovery of novel therapeutic approaches. Finally, we summarize the current knowledge on molecular and circadian regulatory mechanisms of melatonin to overcome neurodegenerative diseases (NDDs) such as Alzheimer's, Parkinson's, Huntington's disease, and amyotrophic lateral sclerosis, however, these findings need to be confirmed by larger, well-designed clinical trials. This review is also expected to uncover the associated molecular alterations in the aging brain and explain how melatonin-mediated circadian restoration of neuronal homeodynamics may increase healthy lifespan in age-related NDDs.

Acarbose, an α-Glucosidase Inhibitor, Maintains Altered Redox Homeostasis During Aging by Targeting Glucose Metabolism in Rat Erythrocytes

Increasing age is the single largest risk factor for a variety of chronic illnesses. As a result, improving the capability to target the aging process leads to an increased health span. A lack of appropriate glucoregulatory control is a recurring issue associated with aging and chronic illness, even though many longevity therapies result in the preservation of glucoregulatory control. In this study, we suggest that targeting glucose metabolism to improve regulatory control can help slow the aging process. Male Wistar rats, both young (age 4 months) and old (age 24 months), were given acarbose (ACA) (30 mg/kg b.w.) for 6 weeks. An array of oxidative stress indicators was assessed after the treatment period, including plasma antioxidant capacity as determined by the ferric reducing ability of plasma (FRAP), reactive oxygen species (ROS), lipid peroxidation (malondialdehyde [MDA]), reduced glutathione (GSH), total plasma thiol (sulfhydryl [SH]), plasma membrane redox system (PMRS), protein carbonyl (PCO), advanced oxidation protein products (AOPPs), advanced glycation end products (AGEs), and sialic acid (SA) in control and treated groups. When compared with controls, ACA administration increased FRAP, GSH, SH, and PMRS activities in both age groups. The treated groups, on the contrary, showed substantial decreases in ROS, MDA, PCO, AOPP, AGE, and SA levels. The effect of ACA on almost all parameters was more evident in old-age rats. ACA significantly increased PMRS activity in young rats; here the effect was less prominent in old rats. Our data support the restoration of antioxidant levels in older rats after short-term ACA treatment. The findings corroborate the potential role of ACA as a putative calorie restriction mimetic.

Aging, circadian disruption and neurodegeneration: Interesting interplay

The circadian system is an intricate molecular network of coordinating circadian clocks that organize the internal synchrony of the organism in response to the environment. These rhythms are maintained by genetically programmed positive and negative auto-regulated transcriptional and translational feedback loops that sustain 24-hour oscillations in mRNA and protein components of the endogenous circadian clock. Since inter and intracellular activity of the central pacemaker appears to reduce with aging, the interaction between the circadian clock and aging continues to elude our understanding. In this review article, we discuss circadian clock components at the molecular level and how aging adversely affects circadian clock functioning in rodents and humans. The natural decline in melatonin levels with aging strongly contributes to circadian dysregulation resulting in the development of neurological anomalies. Additionally, inappropriate environmental conditions such as Artificial Light at Night (ALAN) can cause circadian disruption or chronodisruption (CD) which can result in a variety of pathological diseases, including premature aging. Furthermore, we summarize recent evidence suggesting that CD may also be a predisposing factor for the development of age-related neurodegenerative diseases (NDDs) such as Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD), although more investigation is required to prove this link. Finally, certain chrono-enhancement approaches have been offered as intervention strategies to prevent, alleviate, or mitigate the impacts of CD. This review thus aims to bring together recent advancements in the chronobiology of the aging process, as well as its role in NDDs.

Baicalein maintains redox balance in experimental hyperlipidemic rats

Context: An altered lipid profile may lead to the development of CVD.Objective: We evaluated the protective role of baicalein (BAC) against lipidemic and oxidative stress in hyperlipidemic challenged Wistar rats.Materials and methods: Male Wistar rats were given a high-fat diet (HFD) (suspension (w/v) of 0.5% cholesterol, 3% coconut oil and 0.25% cholic acid for 30 days) to create a hyperlipidemic model. BAC was supplemented to experimental rats (80 mg/kg body weight). Biomarkers of oxidative stress including ROS, FRAP, GSH, PMRS, AGE, MDA, PCO, AOPP, and other parameters (Paraoxonase-1, SGOT, SGPT) including TNF-α and IL-6, were estimated in blood.Results: Oxidative stress and inflammatory markers were significantly increased in the HFD treated group. BAC treatment protected rats from HFD mediated alterations.Discussion & conclusion: Our results indicate that baicalein provides protection against hyperlipidemic stress and redox imbalance induced by HFD in rats.

3-Bromopyruvate, a caloric restriction mimetic, exerts a mitohormetic effect to provide neuroprotection through activation of autophagy in rats during aging

In the present study, attempts have been made to evaluate the potential role of 3 Bromopyruvate (3-BP) a glycolytic inhibitor and a caloric restriction mimetic (CRM), to exert neuroprotection in rats during aging through modulation of autophagy. Young male rats (4 months), and naturally aged (22 months) male rats were supplemented with 3-BP (30 mg/kg b.w., orally) for 28 days. Our results demonstrate a significant increase in the antioxidant biomarkers (ferric reducing antioxidant potential level, total thiol, superoxide dismutase, and catalase activities) and a decrease in the level of pro-oxidant biomarkers such as protein carbonyl after 3-BP supplementation in brain tissues. A significant increase in reactive oxygen species (ROS) was observed due to the mitohormetic effect of 3-BP supplementation in the treated rats. Furthermore, the 3-BP treatment also enhanced the activities of electron transport chain complexes I and IV in aged brain mitochondria thus proving its antioxidant potential at the level of mitochondria. Gene expression analysis with reverse transcriptase-polymerase chain reaction (RT-PCR) was performed to assess the expression of autophagy, neuroprotective and aging marker genes. RT-PCR data revealed that 3-BP up-regulated the expression of autophagy markers genes (Beclin-1 and LC3 β), sirtuin-1, and neuronal marker gene (NSE), respectively in the aging brain. The results suggest that 3-BP induces a mitohormetic effect through the elevation of ROS which reinforces defensive mechanism(s) targeted at regulating autophagy. These findings suggest that consistently low-dose 3-BP may be beneficial for neuroprotection during aging and age-related disorders.

Chitosan reduces inflammation and protects against oxidative stress in a hyperlipidemic rat model: relevance to nonalcoholic fatty liver disease

BACKGROUND

An altered lipid profile may lead to the development of inflammation and NAFLD (Non-alcoholic fatty liver disease). Although statins have a positive effect on blood lipid levels their long-term use is known to cause adverse effects, in this backdrop there is an interest in natural compounds which may affect lipid metabolism and prevent NAFLD. We have examined the effect of Chitosan on rats subjected to a high-fat diet.

METHODS AND RESULTS

Male Wistar middle aged rats (12-16 months) were treated with high-fat diet orally for two months for creating a NAFLD model. Rats were also supplemented with Chitosan (2% chitosan daily) for 2 months. We assessed the activity of antioxidant enzymes, the histopathological profile of the liver. Inflammatory cytokines and adiponectin levels were also measured in serum. HFD induced significant changes in liver tissue and inflammatory markers (Il-6, TNF- alpha, NF-KB). Chitosan treatment protected rats from HFD induced alterations.

CONCLUSIONS

The findings suggest that Chitosan can effectively improve liver lipid metabolism by normalizing cholesterol, triglyceride, lowering NF-KB expression, and protecting the liver from oxidative stress by improving hepatic function. Chitosan also regulates genes related to lipidemic stress i,e leptin and adiponectin.

Baicalein may act as a caloric restriction mimetic candidate to improve the anti-oxidant profile in a natural rodent model of aging

INTRODUCTION

Caloric restriction (CR) is the most effective intervention for extending the life span of vertebrate and invertebrate aging models.. CRMs, which are synthetic or natural chemicals that mimic the biochemical, hormonal, and physiological consequences of calorie restriction, are being researched for anti-aging benefits. Baicalein is a plant-derived polyphenol that has the potential of anti-oxidant, anti-inflammatory, and autophagy inducer. The objective of this study is to evaluate the anti-aging, anti-inflammatory, and antioxidant role of Baicalein in erythrocyte membrane and plasma, and evaluate the efficacy of Baicalein to act as a CRM candidate.

MATERIALS AND METHODS

The present study evaluates the effect of Baicalein on aging biomarkers in normal and aged rats. We study various pro- and anti-oxidant markers, erythrocyte membrane transporters, and eryptosis.

RESULTS

Baicalein supplementation in male Wistar rats significantly alleviated pro-oxidant markers and improved anti-oxidant profile. Improvement was also observed in age-induced alterations in membrane transporters, and eryptosis.

CONCLUSION

Based on the above observations we conclude that Baicalein has the potential to maintain extracellular ROS levels and redox homeostasis during the aging process, an effect which is similar to CR. Thus Baicalein may be a potent CRM candidate for anti-aging interventions.

Capsaicin has potent anti-oxidative effects in vivo through a mechanism which is non-receptor mediated

Capsaicin (8-methyl-N-vanillyl-trans-6-nonenamide) is the active ingredient of chilli peppers and is responsible for the characteristic pungency. The ubiquitous human consumption of chilli peppers indicates their influence on human health. The effect of capsaicin through sensory neurons via TRPV1 activation has been well studied, but its non-neuronal effects are still not extensively explored. The purpose of this study was to investigate the in vivo antioxidant effect of capsaicin on erythrocytes of male Wistar rats. Markers of oxidative stress in blood were determined by assessing the plasma total antioxidant potential, activity of plasma membrane redox system, intracellular glutathione (GSH) level, ROS level, protein oxidation and lipid peroxidation. Results of this study suggest a significant protective effect of capsaicin against oxidative stress by enhancing FRAP, GSH level, PMRS activity and ameliorating ROS, MDA, PCO and AOPP.

Fisetin, a potential caloric restriction mimetic, modulates ionic homeostasis in senescence induced and naturally aged rats

CONTEXT

Fisetin as a caloric restriction mimetic (CRM) exerts numerous beneficial effects on different aging model systems. The effect of fisetin on erythrocyte membrane functions against induced aging is not very clear.

OBJECTIVES

The potential role of fisetin in the modulation of erythrocytes membrane-bound transporters during natural and induced aging in rats was assessed.

MATERIALS AND METHODS

Male Wistar rats were used for natural and D-galactose (D-gal) induced aging model. After supplementation with fisetin, the activities of different membrane transporters and biomarkers of oxidative stress were evaluated.

RESULTS

Fisetin modulated membrane transporters such as calcium-ATPase, sodium potassium-ATPase and sodium hydrogen exchanger during senescence-induced as well as in natural aging. Fisetin also protected oxidative modifications in rat aging.

DISCUSSION AND CONCLUSION

Fisetin supplementation improves the ionic homeostasis, a factor that is involved in the aetiology of several age-associated diseases, in naturally old as well as D-gal induced aged rats.

Melatonin stabilizes age-dependent alterations in erythrocyte membrane induced by 'Artificial Light at Night' in a chronodisrupted model of rat

Growing evidence has shown that Artificial light at night (ALAN) is one of the threatening risk factors which disrupt circadian homeodynamics of cellular processes. The chronobiological role of melatonin seems to represent an important aspect of its contribution to healthy aging. In the present study, we examined the age dependent effect of melatonin on erythrocyte membrane transporters and oxidative stress biomarkers against ALAN to understand the degree of photo-oxidative damage in chronodisrupted rat model. Young (3 months) and old (24 months) male Wistar rats were subdivided in the following four young groups (n = 4) ; (i) control (ii) melatonin (10 mg/kg) (iii) ALAN (500 lx) (iv) ALAN (500 lx) + melatonin (10 mg/kg) and four old groups (n = 4); (v) control (vi) melatonin (10 mg/kg) (vii) ALAN (500 lx) (viii) ALAN (500 lx) + melatonin (10 mg/kg) to the experimental conditions for 10 days. Our findings demonstrated that ALAN significantly enhanced erythrocyte membrane lipid hydroperoxides (LHPs), protein carbonyl (PCO) while reduced total thiol (T-SH), and sialic acid (SA) level with higher amplitude in old ALAN group is restored by exogenous supplementation of melatonin. Activity of membrane transporters, sodium potassium ATPase (NKA) and plasma membrane calcium ion ATPase (PMCA) is significantly reduced meanwhile sodium hydrogen exchanger (NHE) activity is enhanced under the influence of ALAN with higher extent in old groups is effectively ameliorated by melatonin treatment. Further melatonin reduced osmotic fragility of erythrocyte in both young and old rats. It has been concluded from results that ALAN provoked redox insult and disrupt transporters activity more prominently in erythrocyte membrane of aged groups. Exogenous supplementation of melatonin is one of the possible therapeutic approaches to reinforce circadian modulations against ALAN in aged populations.

Protective effect of hesperidin in Poloxamer-407 induced hyperlipidemic experimental rats

Hyperlipidemia is one of the leading causes of, atherosclerosis, and cardiovascular disease. In this study, we evaluated the protective role of hesperidin (HES) against lipidemic stress in a hyperlipidemic model of rats. We developed a hyperlipidemic model of the rat through an i.p dose of poloxamer-407, 0.5 g/kg body weight for 3 alternative days in a week for 30 days and rats were supplemented with HES orally (100 mg/kg body weight) once daily. Bodyweight, fasting glucose, insulin, HOMA-IR index, triglyceride, cholesterol, ROS, FRAP, GSH, PMRS, AGE, MDA, PCO, AOPP, PON-1, TNF-α and IL-6, SGPT and SGOT were estimated in blood and plasma, and histopathology was done in liver tissue. Our data show that oxidative stress, inflammatory markers were increased in the P-407 treated group. Liver tissue histology also changes in the hyperlipidemic groups of rats.HES supplementation protects against P-407 induced alterations and maintains the redox homeostasis. Our results provide evidence that HES protects against lipidemic stress and redox imbalance induced by P-407 in rats.

Chitosan Displays a Potent Caloric Restriction Mimetic Effect in Senescent Rats

Chitosan is a polysaccharide made up of β1,4-linked d-glucosamine (GlcN) and N-acetyl-GlcN. In this study, we evaluated the possible caloric restriction mimetic (CRM) effect of dietary chitosan on systemic redox status, inflammatory biomarkers, and lipid profile in plasma and erythrocyte samples of d-galactose-induced mimetically aged rats. We found a significant increase (p < 0.05) in the reactive oxygen species, protein carbonyl, fasting glucose, body weight, cholesterol, triglyceride, inflammatory markers-interleukin-6 and tumor necrosis factor-alpha in an accelerated senescent rat model. There was also a significant decrease (p < 0.05) in glutathione, advanced glycation end product in senescent rats. Chitosan treatment increased ferric-reducing antioxidant potential, glutathione, plasma membrane-reduced system in accelerated senescent model of rats. Our finding suggests that chitosan has properties similar to a CRM and can effectively maintain the redox homeostasis during the aging process in rat erythrocytes.

Age-dependent effect of continuous 'artificial light at night' on circadian rhythm in male rats: neuroprotective role of melatonin

Circadian disruption due to artificial light at night (ALAN) is an alarming threat to modern society. In the present study we evaluated the protective effect of melatonin on age dependent redox insults and neurochemical deficits induced by ALAN in the brain of chronodisrupted rat model. Young (3 months) and old (22 months) male Wistar rats were exposed to ALAN along with melatonin supplementation (10 mg Kg^-1, oral) for 10 days. Results demonstrated significant increment in the pro-oxidant biomarkers: reactive oxygen species, lipid hydroperoxidation, protein carbonyl, nitric oxide while suppression in the total thiol, ferric reducing antioxidant potential level, superoxide dismutase and catalase activities in the brain of ALAN exposed groups with higher amplitude in aged rats. Further these oxidative modifications were protected by subsequent administration of melatonin. Mitochondrial complexes (C-I to C-IV) activity was significantly altered in young and old ALAN exposed groups with melatonin showing protective effect. Histopathological analysis show dense cytosolic staining and neuronal degeneration in cerebral cortex and different hippocampus regions with greater extent in old ALAN rats effectively moderated by melatonin supplementation. RT-PCR data analysis revealed melatonin effectively downregulated neuroinflammatory (IL-6, TNF α) and neurodegenerative marker (Ngb) while upregulating the aging (Sirt 1) gene expression in both young and old melatonin supplemented ALAN exposed groups. Our results may help in understanding the degree of ALAN induced photo-oxidative damage in neuronal redox homeostasis during aging. We also show that melatonin supplementation might provide a basis for amelioration of oxidative disturbances to improve circadian entrainment in aged populations.

The Antioxidant Efficacy of Wheatgrass (Triticum Aestivum) on Mercuric Chloride (HgCl2) - Induced Oxidative Stress in Rat Model

Mercury is a harmful toxic pollutant, which has hepato-nephrotoxic, hematotoxic, genotoxic and neurotoxic, effects. The aim of the study was to evaluate the protective efficacy of wheatgrass on mercuric chloride (HgCl2) induced oxidative stress and associated complications in rat model. Albino rats were divided into four groups (three rats per group). Group I normal control group. Group II oxidative stressed group received mercuric chloride (0.5 mg/kg/day). Group III only received wheatgrass extract (100 mg/kg/day), whereas Group IV received wheatgrass (100 mg/kg/day) after one hour, followed by mercuric chloride (0.5 mg/kg/day) for 30 days. The results of the study showed that wheatgrass supplementation significantly decreased the HgCl2 induced elevated oxidative stress parameters Plasma Malondialdehyde (MDA) content, Plasma membrane redox system (PMRS), Advanced oxidation protein products (AOPP), simultaneously elevated lipid profile (Total Cholesterol, Triglycerides, Low-density lipoprotein (LDL), liver enzymes as, Plasma Alkaline phosphatase (ALP), Aspartate aminotransferase (AST), and Alanine aminotransferase (ALT), Serum Urea, and Creatinine levels in rats. In addition, wheatgrass treatment improved the antioxidant status in terms of intracellular Reduced Glutathione (GSH), Ferric reducing antioxidant power (FRAP) and 2, 2- diphenyl -1- picrylhydrazyl (DPPH). Therefore it can be concluded that wheatgrass has great potential to diminish the stress-mediated complications and improve the antioxidant status.

Melatonin exerts neuroprotection in a chronodisrupted rat model through reduction in oxidative stress and modulation of autophagy

Circadian disruption due to artificial light affects cellular redox homeostasis and may lead to neurodegenerative diseases. The aim of the present study was to investigate the effect of continuous light exposure (CLE) and continuous dark exposure (CDE) along with melatonin supplementation on neuronal redox status, mitochondrial complexes, membrane bound transporters, inflammation, autophagy and neurodegeneration in chronodisrupted model of rat. In the study artificial light of white LED bulb with 500 lux intensity was used. Melatonin (10 mg/kg b.w., orally) was supplemented to control and CLE groups for 10 days. Standard protocols were employed to measure pro-oxidants, non-enzymatic antioxidants, and mitochondrial complexes in brain tissues. Membrane-bound ion transporter activities were evaluated in the crude synaptosomes. Gene expression analysis was performed to assess the expression of inflammatory, autophagy and neuronal marker genes. Histopathological changes in cerebral cortex and different hippocampus regions of the brain were studied. Melatonin exerted a significant normalization of redox status biomarkers in brain tissue. Further melatonin restored the activities of mitochondrial complexes and synaptosomal membrane bound ion transporters. RT-PCR data revealed that melatonin downregulated the expression of inflammatory (TNF-α, IL-6) autophagy (Atg-3, Beclin-1) and neurodegenerative genes (Ngb and NSE) in CLE group. Melatonin also preserved the histology architecture in cerebral cortex and hippocampus. Our results indicate that melatonin exerts a potent neuroprotective effect through reduction of oxidative stress, inflammation and autophagy. Melatonin supplementation might be a promising neurotherapeutic in the treatment neurodegenerative disorders caused by circadian disturbances.

Promising drug discovery strategies for sirtuin modulators: what lessons have we learnt?

INTRODUCTION

Sirtuins, NAD-dependent protein deacetylases, require NAD⁺ for enzymatic activity. Recent research has indicated that sirtuins have a key role in the regulation of gene expression, the cell cycle, apoptosis, neurodegeneration and several age-related diseases. In mammals, there are seven sirtuin isoforms (SIRT-1-7) that catalyze specific lysine substrate deacetylation.

AREAS COVERED

This review explains the current information on the structure, function and importance of sirtuin modulators. It also explores the possible therapeutic applications of sirtuin modulators and related small molecules in the context of various diseases.

EXPERT OPINION

Sirtuin's modulators open a new area of research for targeting pathological conditions. Sirtuin modulators, through their targeted function, may provide a possible tool for the amelioration of various diseases. However, the search of activators/inhibitors for sirtuins needs further research. The structural elucidation of sirtuins will create an understanding for the development of isoform-specific selective modulators. This could be a useful tool to determine the functions of individual sirtuins as potential therapeutic agents.

Metformin protects red blood cells against rotenone induced oxidative stress and cytotoxicity

CONTEXT

The anti-diabetic medicine metformin has been reported as an anti-ageing drug candidate as it mimics the benefits of caloric restriction and reduces ageing-related oxidative stress in various experimental organisms.

OBJECTIVE

We investigated the possible anti-oxidative role of metformin against rotenone-induced oxidative stress and cytotoxicity in erythrocytes of Wistar rats. Rotenone is a well-known inducer of oxidative stress which leads to a cellular redox imbalance.

MATERIALS AND METHODS

We have co-exposed the experimental rats with rotenone (2.5 mg/kg, i.p.) and metformin (300 mg/kg, orally) for 30 days to investigate the protective effects of metformin on various rotenone-induced impaired oxidative stress biomarkers in rat erythrocytes.

RESULTS

We found that a significant alleviation in the levels of rotenone-induced pro-oxidant and anti-oxidant markers following exposure of metformin.

DISCUSSION AND CONCLUSIONS

Our findings suggest that metformin supplementation shows a protective role in against rotenone-induced redox imbalance and cytotoxicity in rat erythrocytes.

Glucosamine Displays a Potent Caloric Restriction Mimetic Effect in Senescent Rats by Activating Mitohormosis

Aging is strongly correlated with several noncommunicable disorders such as diabetes, obesity, cardiovascular disease, and neurodegenerative conditions. Glucosamine (2-amino-2-deoxy-d-glucose, GlcN) is a naturally occurring amino sugar and is reported to act as a caloric restriction mimetic (CRM). In young and d-galactose-induced accelerated rat aging models, we tested a persistent oral dietary dose of GlcN and evaluated various aging biomarkers in erythrocytes and plasma. A significant increase in the reactive oxygen species (ROS) was observed in GlcN-treated young and accelerated senescent rat model. Increased value of ferric reducing ability of plasma (FRAP), superoxide dismutase, catalase, and plasma membrane redox system (PMRS) was observed. We suggest that GlcN induces a mitohormetic impact by a transient increase in ROS. Our findings indicate that GlcN may be a successful CRM.

Piperine protects oxidative modifications in human erythrocytes

OBJECTIVES

Piperine (1-piperoyl piperidine), a major alkaloid constituent of Piper nigrum L. and Piper longum L. has pleiotropic biological effects, but the mechanism(s) involved remain to be elucidated. The current study was conducted to examine the efficacy of antioxidant ability of piperine on t-BHP induced markers of oxidative stress in human erythrocytes.

METHODS

Healthy human erythrocytes and erythrocytes membrane was stressed with free radical inducer chemical; t-BHP (10^-5 M), and the effects of piperine was measured against free radical mediated modification in lipid and protein content, -SH and GSH value with antioxidant potential.

RESULTS

The results demonstrate that treatment of erythrocytes with piperine (10^-5 to 10^-7 M) significantly (p<0.05) ameliorated the adverse consequences of oxidative stress as evidenced by prevention of oxidation of erythrocyte reduced glutathione, membrane thiols, proteins, and peroxidation of lipids; the effects were in correlation with ferric reducing and radical scavenging abilities of piperine.

CONCLUSIONS

The study concludes that piperine possesses potent anti-oxidant potential which may explain many of its observed biological effects.

Plasma from Young Rats Injected into Old Rats Induce Antiaging Effects

An experimental novel antiaging intervention strategy is based on the concept of parabiosis, which involves long-term treatment with factors derived from young blood facilitating rejuvenation of old individuals. In this study, we employed blood plasma from young rats as an intervention strategy to evaluate whether this could impact aging biomarkers in aged rats. The biomarkers studied include: reactive oxygen species, the ferric reducing ability of plasma, plasma membrane redox system, reduced glutathione, malondialdehyde, protein carbonyl, and advanced oxidation protein products in blood. Additionally, the level of tumor necrosis factor-α and interleukin-6 were also estimated in blood. We found that old rats injected with plasma from young rats were protected from oxidative stress. Thus, this study provides some evidence of the rejuvenating effects of young plasma. We hypothesize that young plasma may contain certain "factors," which may be responsible for the observed effects. The mechanism of action is not clearly understood and is open to further studies.

Age-dependent altered redox homeostasis in the chronodisrupted rat model and moderation by melatonin administration

Circadian disruption or chronodisruption (CD) occurs when day-night cycles and other internal rhythms are not adjusted to environmental light-dark regimens and are unable to synchronize among each other. Artificial light-induced oxidative stress is a major concern as the circadian physiology of the cell is chronically altered due to suppression of the time-keeping hormone, melatonin. The relationship between age-related impaired redox status and disrupted circadian rhythms is still not fully understood. The present study evaluated the effect of artificial light at night (ALAN) with respect to aging and role of melatonin supplementation. This study was conducted on young (3 months) and old (24 months) male Wistar rats subdivided into four groups control (C), melatonin treated (MLT), artificial light at night (ALAN), and ALAN+MLT group. Pronounced changes were observed in the old compared to the young rats. Reactive oxygen species (ROS), malondialdehyde (MDA), plasma membrane redox system (PMRS), protein carbonyl (PCO), and sialic acid (SA) were significantly (p ≤ 0.05) increased, while ferric reducing ability of plasma (FRAP) and reduced glutathione (GSH) were significantly (p ≤ 0.05) suppressed in light-exposed young and old animals compared to their age-matched controls. Advanced oxidation protein products (AOPP) increased non-significantly in young rats of the ALAN group; however, significant (p ≤ 0.05) changes were observed in the old rats of the ALAN group compared to their respective controls. Advanced glycation end products (AGEs) increased and acetylcholinesterase (AChE) activity decreased, significantly (p ≤ 0.05) in young animals of the ALAN group, while nonsignificant changes of both parameters were recorded in the old animals of the ALAN groups compared with their age-matched controls. Melatonin supplementation resulted in maintenance of the normal redox homeostasis in both young and old animal groups. Our study suggests that aged rats are more susceptible to altered photoperiod as their circadian redox homeostasis is under stress subsequent to ALAN. Melatonin supplementation could be a promising means of alleviating age-related circadian disturbances, especially in light-polluted areas.

Time restricted feeding provides a viable alternative to alternate day fasting when evaluated in terms of redox homeostasis in rats

Intermittent fasting (IF) is a non-pharmacological dietary approach for intervening into aging in different organisms. We evaluated the efficacy of time restricted dietary regimen and alternate-day fasting in rats by measuring redox parameters which are frequently used as signature biomarkers of aging. Wistar rats (8 months) were divided into three groups of six rats each. Group I: Control; Group II: Time-restricted feeding (TRF) (fed and fasted at a ratio of 16:8 h respectively) and Group III. Alternate day feeding (ADF) (fed and fasted on alternate days), for a period of 1 month. The biomarkers of antioxidant defense and oxidative stress: FRAP, GSH, PMRS, ROS, AGE, MDA, PCO, AOPP, TNF-α and IL-6, were determined. Our results suggest that, based on predominant aging biomarkers, TRF has a similar effect on rats compared with ADF evaluated in terms of redox homeostasis. Observed results defend our purpose that the ADF and TRF methods are reliable dietary restriction regimens and subsequently improve the metabolic profile and redox homeostasis in rats.

2 -Deoxy - d-glucose at chronic low dose acts as a caloric restriction mimetic through a mitohormetic induction of ROS in the brain of accelerated senescence model of rat

INTRODUCTION

Aging induces significant molecular alteration in brain morphology. Glycolytic inhibitor 2-Deoxy-d-glucose (2-DG) is considered to act as a caloric restriction mimetic (CRM) but it is correlated with elevated mortality risk in rats at persistent high dosage.

MATERIALS AND METHODS

In young and d-galactose induced accelerated senescent rat aging models, we tested a persistent low-dose dietary 2-DG administration and evaluated various aging biomarkers in brain tissue.

RESULTS

A significant increase in reactive oxygen species (ROS) was observed in 2-DG treated (both young and accelerated senescent rat model). Increased Ferric reducing antioxidant potential (FRAP) value, Superoxide Dismutase (SOD), Catalase (CAT), and activity of mitochondrial complexes I and IV was observed. There was also significant improvements in the autophagy expression of genes (Beclin-1 and Atg-3) after 2- DG treatment.

CONCLUSION

We propose that 2-DG induces a mitohormetic effect through elevation of ROS which reinforces defensive mechanism(s) through increased FRAP, SOD, CAT and autophagy gene expression. Our observations indicate that a consistently low dose 2-DG could be a valuable CRM.

Redox modulating effects of grape juice during aging

Background Polyphenols are known because of their phytochemical constituents having antioxidative properties. In this regard, grape juice is highly enriched with polyphenolic constituents, and its supplementation has been known to improve many health and age-associated diseases and risk factors. Our study was entirely dedicated to evaluating the positive effects of grape juice on young and old rats' erythrocytes and plasma. Methods Young (4 months) and old (24 months) male Wistar rats were given an oral dose of grape juice for 28 days. They were grouped into four categories (n = 6): Group I: young control rats; Group II: young grape juice treated rats; Group III: old control rats; Group IV: old treated rats. The treated groups were administered with 10 μL/g of grape juice according to body weight. The following biomarkers of antioxidant defense were measured: ferric reducing ability of plasma (FRAP), reactive oxygen species (ROS), plasma membrane redox system (PMRS), glutathione (GSH), osmotic fragility, and the decrease in lipid peroxidation measured in terms of malondialdehyde (MDA) levels. Results A significant increase (p<0.05) in antioxidant levels of FRAP, PMRS, and GSH and a significant decrease (p<0.05) in oxidized products such as ROS and MDA were seen in the treated rats in comparison to the controls. The decrease in ROS and rise in FRAP and PMRS levels suggest the ability of grape juice to combat oxidative stress effectively. Conclusion We propose the role of grape juice as a potent antioxidant because of its easy bioavailability and its role in combating stress. Our results also approve grape juice as a possible antiaging agent.

Metformin ameliorates acetaminophen-induced sub-acute toxicity via antioxidant property

Acetaminophen or N-acetyl-p-amino-phenol (APAP) is a drug which is available over-the-counter for fever and pain. Its overdosing causes oxidative stress and subsequent acute liver damage. In the present study, we scrutinized the protective effect of metformin co-treatment in APAP induced blood and liver sub-acute toxicity. This is a pre-clinical study in which male Wistar Rats (BW: 300 ± 20 g) were orally co-treated with APAP (1 g/kg/day) and metformin (300 mg/kg/day) for 28-days. Pro- and anti-oxidant markers viz reactive oxygen species, protein carbonyl, malondialdehyde (MDA), the ferric reducing ability of plasma (FRAP), plasma membrane redox system(PMRS) and reduced glutathione (GSH) were evaluated in blood. Additionally, in liver tissue, catalase (CAT), superoxide dismutase (SOD), MDA and GST level were also evaluated. Histological study and estimation of alanine aminotransferase (ALT), and aspartate aminotransferase (AST) level in serum were performed. APAP induces pro-oxidant markers as well as reduces anti-oxidant markers in blood and liver. Hepatic tissues degeneration and vacuolization of hepatocytes were evident after APAP treatment. Metformin treatment reduces pro-oxidant markers as well as increases anti-oxidant markers in both tissues. It also improves liver tissue architecture after treatment. The outcome of this study suggests that metformin has protective capability against APAP-induced blood and liver toxicity. Thus, metformin co-treatment with APAP attenuates oxidative stress and its consequences.

Redox homeostasis in a rodent model of circadian disruption: Effect of melatonin supplementation

Continuous light or dark photoperiods are the leading cause of disruption in the circadian rhythm of day-night cycle. The purpose of this study was to understand the cellular redox balance in a model of circadian disrupted rat model and determine the effect of melatonin supplementation. Young male Wistar rats were randomly divided into five groups (n = 4). Group (I): normal day-night (12 h:12 h) cycle, Group (II): normal rats treated with melatonin, Group (III): rats subjected to continuous light exposure (CLE), Group (IV): CLE rats treated with melatonin, and Group (V) Rats subjected to continuous dark. Melatonin (10 mg/kg) was administered orally at dusk to the Group (II) & (IV). Rats were sacrificed after 10 days of treatment and biomarkers of oxidative stress were evaluated. Results demonstrated significant (p < 0.05) increase of malondialdehyde (MDA), plasma membrane redox system (PMRS), protein carbonyl oxidation (PCO), advanced oxidation protein products (AOPPs), and advanced glycation end products (AGEs) during CLE. A significantly (p < 0.05) decreased level of reduced glutathione (GSH) and ferric reducing antioxidant potential in plasma (FRAP) was also observed during CLE. Treatment with melatonin in CLE rats showed reduced level of MDA, PMRS, PCO, AOPPs and AGEs while GSH and FRAP activity were increased. During continuous dark exposure (CDE) the biomarkers of oxidative stress were attenuated compared to control. Supplementation of melatonin could be a promising strategy to maintain redox homeostasis during prolonged condition of light exposure and other conditions of redox imbalance.

Invertebrate and vertebrate models in aging research

Therapeutic interventions that can delay age associated diseases and ensure a longer health-span is a major goal of aging research. Consequent to understanding that aging is a modifiable trait, a large number of studies are currently being undertaken to elucidate the mechanism(s) of the aging process. Research on human aging and longevity is difficult, due to longer time frame, ethical concerns and environmental variables. Most of the present day understanding about the aging process comes through studies conducted on model organisms. These provide suitable platforms for understanding underlying mechanism(s) which control aging and have led to major discoveries that emphasize the evolutionarily conserved molecular pathways as key players that respond to extra and intracellular signals. This is a review of various invertebrate and vertebrate models including yeast, Drosophila, C. elegans, rodents, naked mole rat, and birds, currently used in aging research with emphasis on how well they can mimic aging in higher animals and humans.

Fisetin, a potential caloric restriction mimetic, attenuates senescence biomarkers in rat erythrocytes

An imbalanced redox status is a hallmark of the aging process. Caloric restriction mimetics (CRMs) are compounds that produce caloric restriction benefits at the molecular, cellular, and physiological level, translating into health-promoting effects. Fisetin is the least explored CRM, and its role in modulating oxidative stress during aging is not clearly known. This study investigated the antioxidative and protective potential of fisetin in a rat model of d-galactose (D-gal)-induced accelerated senescence, and in naturally aged rat erythrocytes. Young rats (4 months), aged D-gal-induced rats [24 months; 500 mg/kg body mass (b.m.); subcutaneous injection] and naturally aged D-gal-induced rats [24 months; 500 mg/kg b.m.; subcutaneous injection] were supplemented with fisetin (15 mg/kg b.m.; orally) for 6 weeks. The resulting data indicated that supplementation with fisetin suppresses aging-induced increases in the levels of reactive oxygen species, eryptosis, lipid peroxidation, and protein oxidation. Our data also show that fisetin significantly increases the levels of antioxidants and activates the plasma membrane redox system. Taken together, the findings show that a fisetin-rich diet could be an anti-aging intervention strategy.

Effect of oral supplementation of composite leaf extract of medicinal plants on biomarkers of oxidative stress in induced diabetic Wistar rats

Present study was conducted to evaluate the effect of oral supplementation of composite extract of leaves (CLE) of four medicinal plants; Aegle marmelos, Ocimum sanctum, Murraya koenigii and Azadirachta indica on markers of oxidative stress in brain tissues of alloxan-induced diabetic rats in vivo. Enhanced lipid peroxidation, protein oxidation and reduced antioxidative defence systems were measured in brain tissues of diabetic rats. Supplementation of CLE, once in a day for 35 days significantly (p < .05) protected the peroxidation of lipid, oxidation of protein and ameliorated the antioxidant defence in brain tissue of diabetic rats. It was observed that the insulin-like effect of CLE was dose dependent; higher effect at higher doses. The results of the study suggest that supplementation CLE may provide an overall homeostasis and significant neuro-protection through rescuing brain cells from oxidative abuse and accelerating brain antioxidative defence during advanced stage of hyperglycaemia.

N-acetyl-l-cysteine attenuates oxidative damage and neurodegeneration in rat brain during aging

N-acetyl-l-cysteine (NAC) is a precursor of cysteine, which is known to increase the level of glutathione (GSH) in the brain. Several neurodegenerative changes linked to oxidative stress take place in the aging brain. This study aimed to assess the neuroprotective effect of NAC supplementation on age-dependent neurodegeneration in the rat brain. Young (4 months) and old (24 months) Wistar rats (n = 6 rats/group) were supplemented with NAC (100 mg/kg b.w. orally) for 14 days. Enzymatic and nonenzymatic antioxidants such as superoxide dismutase and catalase, and GSH and total thiol respectively, prooxidants such as protein carbonyl, advanced oxidation protein products, reactive oxygen species, and malondialdehyde were assessed in the brain homogenates. Furthermore, nitric oxide level, acetylcholinesterase activity, and Na⁺/K⁺-ATPase activity were measured and gene expression studies were also performed. The results indicated that NAC augmented the level of enzymatic and nonenzymatic antioxidants with a significant reduction in prooxidant levels in old rats. NAC supplementation also downregulated the expression of inflammatory markers (TNF-α, IL-1β, IL-6) and upregulated the expression of marker genes associated with aging (sirtuin-1) and neurodegeneration (neuron-specific enolase, neuroglobin, synapsin-I, myelin basic protein 2) in old rats. The present findings support a neuroprotective role of NAC which has therapeutic implication in controlling age-related neurological disorders.

Whey protein concentrate supplementation protects rat brain against aging-induced oxidative stress and neurodegeneration

Whey protein concentrate (WPC) is a rich source of sulfur-containing amino acids and is consumed as a functional food, incorporating a wide range of nutritional attributes. The purpose of this study is to evaluate the neuroprotective effect of WPC on rat brain during aging. Young (4 months) and old (24 months) male Wistar rats were supplemented with WPC (300 mg/kg body weight) for 28 days. Biomarkers of oxidative stress and antioxidant capacity in terms of ferric reducing antioxidant potential (FRAP), lipid hydroperoxide (LHP), total thiol (T-SH), protein carbonyl (PC), reactive oxygen species (ROS), nitric oxide (NO), and acetylcholinesterase (AChE) activity were measured in brain of control and experimental (WPC supplemented) groups. In addition, gene expression and histopathological studies were also performed. The results indicate that WPC augmented the level of FRAP, T-SH, and AChE in old rats as compared with the old control. Furthermore, WPC-treated groups exhibited significant reduction in LHP, PC, ROS, and NO levels in aged rats. WPC supplementation also downregulated the expression of inflammatory markers (tumor necrosis factor alpha, interleukin (IL)-1β, IL-6), and upregulated the expression of marker genes associated with autophagy (Atg3, Beclin-1, LC3B) and neurodegeneration (neuron specific enolase, Synapsin-I, MBP-2). The findings suggested WPC to be a potential functional nutritional food supplement that prevents the progression of age-related oxidative damage in Wistar rats.

Rapamycin mitigates erythrocyte membrane transport functions and oxidative stress during aging in rats

Erythrocyte membrane is a suitable model to study various metabolic and physiological functions as it undergoes variety of biochemical changes during aging. An age-dependent modulatory effect of rapamycin on erythrocyte membrane functions is completely unknown. Therefore, the present study was undertaken to investigate the effect of rapamycin on age-dependent impaired activities of transporters/exchangers, altered levels of redox biomarkers, viz. protein carbonyl (PC), lipid hydroperoxides (LHs), total thiol (-SH), sialic acid (SA) and intracellular calcium ion [Ca²⁺]i, and osmotic fragility of erythrocyte membrane. A significant reduction in membrane-bound activities of Na⁺/K⁺-ATPase (NKA) and Ca²⁺-ATPase (PMCA), and levels of -SH and SA was observed along with a simultaneous induction in Na⁺/H⁺ exchanger (NHE) activity and levels of [Ca²⁺]i, PC, LH and osmotic fragility in old-aged rats. Rapamycin was found to be a promising age-delaying drug that significantly reversed the aging-induced impaired activities of membrane-bound ATPases and altered levels of redox biomarkers.