Effects of aging on the plasma levels of nesfatin-1 and adiponectin

Decreased level of plasma nesfatin-1 in rats exposed to cell phone radiation is correlated with thyroid dysfunction, oxidative stress, and apoptosis

CONTEXT

Exposure to Electomagnetic radiation fields of cell phones causes thyroid dysfunction and a previous study revealed that nesfatin-1 may affect functions of the thyroid gland.

OBJECTIVE

To study the role of nesfatin-1 on functions of rat's thyroid gland exposed to EMRF.

MATERIALS AND METHODS

Thirty adult male rats were divided equally into 3 groups as group I, group II and group III. The experiment extended for 30 days then the plasma nesfatin-1 level, thyroid functions, and thyroid tissue oxidative stress were assessed. Also; histological and immunohistochemical study studies were done to evaluate structural and apoptotic changes of the thyroid gland.

RESULTS

There was a significant decrease in plasma nesfatin-1 level and thyroid functions with an increase in oxidative stress and apoptosis. Interestingly, there was a correlation between nesfatin-1 level and markers of thyroid function, oxidative stress and apoptosis.

CONCLUSION

Nesfatin-1 plays a role in thyroid dysfunctions of rats exposed to mobile phone radiation.

Adipose tissue and ovarian aging: Potential mechanism and protective strategies

Ovarian aging occurs approximately 10 years prior to the natural age-associated functional decline of other organ systems. With the increase of life expectancy worldwide, ovarian aging has gradually become a key health problem among women. Therefore, understanding the causes and molecular mechanisms of ovarian aging is very essential for the inhibition of age-related diseases and the promotion of health and longevity in women. Recently, studies have revealed an association between adipose tissue (AT) and ovarian aging. Alterations in the function and quantity of AT have profound consequences on ovarian function because AT is central for follicular development, lipid metabolism, and hormonal regulation. Moreover, the interplay between AT and the ovary is bidirectional, with ovary-derived signals directly affecting AT biology. In this review, we summarize the current knowledge of the complex molecular mechanisms controlling the crosstalk between the AT and ovarian aging, and further discuss how therapeutic targeting of the AT can delay ovarian aging.

Adipose tissue and age‑dependent insulin resistance: New insights into WAT browning (Review)

Insulin resistance (IR) is defined as impaired insulin function, reduced glucose uptake and increased glucose production, which can result in type II diabetes, metabolic syndrome and even bone metabolic disorders. A possible reason for the increasing incidence of IR is population aging. Adipose tissue (AT) is an important endocrine organ that serves a crucial role in whole-body energy homeostasis. AT can be divided into white AT (WAT), beige AT and brown AT (BAT). Several mechanisms have been previously associated with age-dependent IR in WAT. However, BAT, a metabolically active tissue, controls the levels of plasma glucose and triglyceride metabolism. Therefore, the present review aimed to summarize the mechanisms of age-dependent IR induced by AT and to determine the role of WAT browning in achieving positive therapeutic outcomes in age-dependent IR.

Integrative genomics reveal a role for MCPIP1 in adipogenesis and adipocyte metabolism

Obesity is considered a serious chronic disease, associated with an increased risk of developing cardiovascular diseases, non-alcoholic fatty liver disease and type 2 diabetes. Monocyte chemoattractant protein-1-induced protein-1 (MCPIP1) is an RNase decreasing stability of transcripts coding for inflammation-related proteins. In addition, MCPIP1 plays an important role in the regulation of adipogenesis in vitro by reducing the expression of key transcription factors, including C/EBPβ. To elucidate the role of MCPIP1 in adipocyte biology, we performed RNA-Seq and proteome analysis in 3T3-L1 adipocytes overexpressing wild-type (WTMCPIP1) and the mutant form of MCPIP1 protein (D141NMCPIP1). Our RNA-Seq analysis followed by confirmatory Q-RT-PCR revealed that elevated MCPIP1 levels in 3T3-L1 adipocytes upregulated transcripts encoding proteins involved in signal transmission and cellular remodeling and downregulated transcripts of factors involved in metabolism. These data are consistent with our proteomic analysis, which showed that MCPIP1 expressing adipocytes exhibit upregulation of proteins involved in cellular organization and movement and decreased levels of proteins involved in lipid and carbohydrate metabolism. Moreover, MCPIP1 adipocytes are characterized by decreased level of insulin receptor, reduced insulin-induced Akt phosphorylation, as well as depleted Glut4 level and impaired glucose uptake. Overexpression of Glut4 in 3T3-L1 cells expressed WTMCPIP1 rescued adipogenesis. Interestingly, we found decreased level of MCPIP1 along with an increase in body mass index in subcutaneous adipose tissue. The presented data show a novel role of MCPIP1 in modulating insulin sensitivity in adipocytes. Overall, our findings demonstrate that MCPIP1 is an important regulator of adipogenesis and adipocyte metabolism.

Antioxidant/Anti-Inflammatory Effects of Caloric Restriction in an Aged and Obese Rat Model: The Role of Adiponectin

Caloric restriction (CR) represents a powerful intervention for extending healthspan and lifespan in several animal models, from yeast to primates. Additionally, in humans, CR has been found to induce cardiometabolic adaptations associated with improved health. In this study, we evaluated in an aged and obese rat model the effect of long-term (6 months) caloric restriction (−40%) on the oxidative/inflammatory balance in order to investigate the underlining mechanisms. In plasma, we analyzed the oxidative balance by photometric tests and the adiponectin/tumor necrosis factor-α-induced gene/protein 6 (TSG-6) levels by Western blot analysis. In the white adipose tissue, we examined the protein levels of AdipoR1, pAMPK, NFκB, NRF-2, and glutathione S-tranferase P1 by Western blot analysis. Our results clearly showed that caloric restriction significantly improves the plasmatic oxidative/inflammatory balance in parallel with a major increase in circulating adiponectin levels. Additionally, at the level of adipose tissue, we found a positive modulation of both anti-inflammatory and antioxidant pathways. These adaptations, induced by caloric restriction, with the achievement of normal weight, suggest that inflammatory and redox imbalance in obese aged rats appear to be more linked to obesity than to aging.

Age Associated Changes in Transcription of Adiponectin, AdipoR1 and AdipoR2 Genes in Pancreas of Rats

Objective

Adiponectin has a crucial role in the function, proliferation and viability of β-cell via action of two receptors: AdipoR1 and AdipoR2. Nevertheless, age related change of Adiponectin system genes in pancreas is unclear or controversial. This study sought to investigate the effects of aging process on serum Adiponectin levels, Adiponectin and its receptor expression in the rat pancreas.

Materials and Methods

In this experimental study, insulin resistance markers including serum insulin and glucose concentrations, homeostatic model assessment of insulin resistance (HOMA-IR), oral glucose tolerance test (OGTT), glucose induced insulin secretion (GIIS), serum Adiponectin levels, pancreatic expression of Adiponectin and its receptors were studied in male Sprague-Dawley rats at the age of 2, 5, 10, 18, 52 and 72 weeks of age.

Results

We found that aging triggered signs of insulin resistance characteristics in rats at 72 age weeks including marked insulin reduction, hyperglycemia and increased HOMA-IR. Circulating Adiponectin as well as pancreatic expression of Adiponectin and AdipoR1 was gradually decreased with age, while the opposite expression pattern of AdipoR2 was observed in the old rats.

Conclusion

Because Adiponectin and Adiponectin signaling have crucial role in β-cell function and viability, we concluded that reduction of Adiponectin signaling may be involved in aging induced β-cell dysfunction. As a result, manipulation of Adiponectin signaling may be a beneficial approach for improvement of β-cell function in the old people.

Eccentric resistance training and β-hydroxy-β-methylbutyrate free acid affects muscle PGC-1α expression and serum irisin, nesfatin-1 and resistin in rats

The hypothalamus controls metabolism and feeding behaviour via several signals with other tissues. Exercise and supplements can change hypothalamic signalling pathways, so the present study investigated the influence of eccentric resistance training and β-hydroxy-β-methylbutyrate free acid supplementation on PGC-1α expression, serum irisin, nesfatin-1 and resistin concentrations. Thirty-two male rats (8 weeks old, 200±17 g body mass) were randomly allocated to control, β-hydroxy-β-methylbutyrate free acid supplementation (HMB), eccentric resistance training (ERT), and β-hydroxy-β-methylbutyrate free acid supplementation plus eccentric resistance training (HMB+ERT) groups. Training groups undertook eccentric resistance training (6 weeks, 3 times a week) and supplement groups consumed β-hydroxy-β-methylbutyrate free acid (HMB-FA) orally (76 mg kg^-1 day^-1). Twenty-four hours after the last training session, serum and triceps brachii muscle samples were collected and sent to the laboratory for analysis. Two-way ANOVA and Pearson correlation were employed (significance level: P<0.05). The results showed that eccentric resistance training increases skeletal muscle PGC-1α gene expression, as well as serum levels of irisin and nesfatin-1 (P=0.001). Eccentric resistance training decreased the serum concentration of resistin (P=0.001). HMB-FA supplementation increased skeletal muscle PGC-1α gene expression (P=0.002), as well as the serum concentration of irisin and nesfatin-1 (P=0.001), but decreased the serum concentration of resistin (P=0.001). Significant correlations were observed between PGC-1α gene expression and serum concentrations of irisin, nesfatin-1 and resistin. HMB-FA supplementation with eccentric resistance training may induce crosstalk between peptide release from other tissues and increases maximal muscle strength. The combination of the two interventions had a more substantial effect than each in isolation.

The relation of serum nesfatin-1 level with anthropometric and metabolic parameters in children and adolescents: A prospective observational study

Nesfatin-1, a recently discovered anorexigenic neuropeptide, seems to play an important role in hypothalamic pathways regulating food intake and energy homeostasis. The aim of this study was to evaluate the relation of serum nesfatin-1 level with metabolic and anthropometric parameters in children and adolescents.This study prospectively included 78 Korean children and adolescents (42 obese/overweight group and 36 healthy control group). Fasting serum nesfatin-1 was quantitatively assayed by ELISA. Lipid profile, fasting blood glucose, fasting insulin, and the homeostasis model assessment of insulin resistance (HOMA-IR) were measured as metabolic parameters.Serum nesfatin-1 levels were significantly lower in obese/overweight group than in control group (median 1.4 vs 2.0 ng/mL; P = .003). Pubertal subjects have the lower serum nesfatin-1 level than pre-pubertal subjects (median 1.5 vs 2.6 ng/mL; P = .02). Nesfatin-1 levels negatively correlated with chronological age (r = -0.37; P = .001), BMI (r = -0.33; P = .003), and BMI SDS (r = -0.26; P = .02).In conclusion, our results suggest that serum nesfatin-1 negatively correlated with BMI in children and adolescents. It suggests that nesfatin-1 might have an important role in regulation of food intake in obese children and adolescents.

May nesfatin-1 be a state marker in major depressive disorder with suicidal ideation?

The best known effects of nesfatin-1 are on appetite and metabolic regulation. Moreover, several research suggest that nesfatin-1 play a role in stress responses. This molecule may be involved in the pathophysiology of mood disorders and suicidal behavior. We compared nesfatin-1 levels between depressed patients with suicidal ideation (n = 32, mean ± SD, 1,40 ± 0.11), without suicidal ideation(n = 31, 1.46 ± 0.14) and healthy controls (n = 32, 1.52 ± 0.13). Suicidal ideation was assessed with the Suicide Probability Scale, Scale for Suicide Ideation and depressive symptoms were evaluated with the Hamilton Depression Rating Scale. Blood samples were collected to measure serum nesfatin-1levels by using ELISA method. The study revealed that serum nesfatin-1 levels were significantly lower in MDD with suicidal ideation than in healthy volunteers (p < 0.001). There were a negative correlation between the scores of suicidal ideation and nesfatin-1 levels in MDD with SI group (r = -0.215; p = 0.016). In the future, nesfatin-1 levels may one day be applied in predicting and monitoring patients' suicide risk. Further prospective studies are required to elucidate this potential association.

Expression of genes involved in carbohydrate-lipid metabolism in muscle and fat tissues in the initial stage of adult-age obesity in fed and fasted mice

C57Bl mice exhibit impaired glucose metabolism by the late adult age under standard living conditions. The aim of this study was to evaluate white adipose tissue (WAT), brown adipose tissue (BAT), and skeletal muscle expression of genes involved in carbohydrate‐lipid metabolism at postpubertal stages preceding the late adult age in C57Bl mice. Muscle mRNA levels of uncoupling protein 3 (Ucp3) and carnitine palmitoyltransferase 1 (Cpt1) (indicators of FFA oxidation), WAT mRNA levels of hormone‐sensitive lipase (Lipe) and lipoprotein lipase (Lpl) (indicators of lipolysis and lipogenesis), muscle and WAT mRNA levels of the type 4 glucose transporter Slc2a4 (indicators of insulin‐dependent glucose uptake), and BAT mRNA levels of uncoupling protein 1 (Ucp1) (indicator of thermogenesis) were measured in fed and 16 h‐fasted mice in three age groups: 10‐week‐old (young), 15‐week‐old (early adult), and 30‐week‐old (late adult). Weight gain from young to early adult age was not accompanied by changes in WAT and BAT indexes and biochemical blood parameters. Weight gain from early to late adult age was accompanied by increased WAT and BAT indexes and decreased glucose tolerance. Muscle Ucp3 and Cpt1 mRNA levels and WAT Lipe and Slc2a4 mRNA levels increased from young to early adult age and then sharply decreased by the late adult age. Moreover, BAT Ucp1 mRNA level decreased in the late adult age. Fasting failed to increase muscle Cpt1 mRNA levels in late adult mice. These transcriptional changes could contribute to impaired glucose metabolism and the onset of obesity in late adult mice during normal development.

Visceral Fat Area and Serum Adiponectin Level Predict the Development of Metabolic Syndrome in a Community-Based Asymptomatic Population

Background

Although it has been demonstrated that visceral adipose tissue content and serum levels of adiponectin are associated with metabolic syndrome, their predictive potential for the development of metabolic syndrome remains to be elucidated.

Methods

We studied 1,130 participants of the Seoul Metabolic Syndrome cohort. A total of 337 subjects without metabolic syndrome underwent the follow-up evaluation and finally analyzed. Visceral fat area (VFA) was measured using dual bioelectrical impedance analysis. We compared the 1-year incidence rate of metabolic syndrome among four different groups: Group 1 (high adiponectin level and low VFA), Group 2 (low adiponectin level and low VFA), Group 3 (high adiponectin level and high VFA) and Group 4 (low adiponectin level and high VFA).

Results

Median follow-up duration was 17 months. Cut-off points of adiponectin level and VFA for metabolic syndrome were 7.34 ng/ml and 84 cm² for men, and 12.55 and 58 cm² ng/ml for women, respectively. The incidence of metabolic syndrome was the highest in Group 4 (Group 1; 16.47%, Group 2; 22.08%, Group 3; 25%, and Group 4; 46.15%, p<0.001). Adjusted logistic regression analyses for metabolic syndrome prediction demonstrated that Group 4 exhibited the highest odds ratio compared with Group 1 (4.918 [2.05–11.795]), which was predominantly affected by waist circumference and serum triglyceride levels. Notably, triglyceride/high-density lipoprotein cholesterol (TG/HDL) ratio was significantly higher in Group 4 (p = 0.017).

Conclusion

Incidence rate of metabolic syndrome was the highest in subjects with low serum adiponectin levels and high visceral fat area. Higher TG/HDL ratio in these subjects suggested insulin resistance may contribute to the development of metabolic syndrome.

Serum NUCB2/nesfatin-1 levels in different stages of alcohol dependence: Is there a relationship with craving?

INTRODUCTION

In the literature, the relationship between appetite regulating peptides and alcohol craving is on the debate.

AIM

This study aims to investigate serum level of NUCB2/nesfatin-1, which is discovered as appetite-related neuropeptide, in patients with alcohol dependence who were in craving and abstaining phase and to compare with healthy controls.

SETTINGS AND DESIGN

Research, Treatment, and Training Center for Alcohol and Substance Dependence, (AMATEM) Bakirkoy Training and Research Hospital for Psychiatry Neurology and Neurosurgery, Istanbul, case-control and prospective study design were used.

STATISTICAL ANALYSIS

Chi-square, Mann-Whitney U, paired samples, independent samples t- and Pearson correlation tests were used for analysis.

MATERIALS AND METHODS

Forty-three patients with alcohol dependence who have been admitted for detoxification and thirty healthy controls were included in the study. The blood samples were drawn after the 1^st day of admission and postdetoxification treatment in inpatients who reached to abstinence period and from 30 healthy controls. The Penn Alcohol Craving Scale and the Obsessive Compulsive Drinking Scale were applied to detect craving scores.

RESULTS

Initial serum NUCB2/nesfatin-1 levels in patients were significantly lower than in the healthy control group (P < 0.001). The NUCB2/nesfatin-1 level of initial phase was significantly lower than abstinence phase (P = 0.027). No correlation was found between craving scores and NUCB2/nesfatin-1 level (P > 0.05).

CONCLUSION

This study is the first that showed significant differences of serum NUCB2/nesfatin-1 level according to different stages of alcohol dependence. Plasma NUCB2/nesfatin-1 levels were lower in highest craving phase and tended to normalize after abstinence. Since we could not find a correlation between craving and NUCB2/nesfatin-1 levels, the increase of NUCB2/nesfatin-1 in abstinence phase might have been resulted from other reasons apart from craving.

Role of Nesfatin-1 in the Reproductive Axis of Male Rat

Nesfatin-1 is an important molecule in the regulation of reproduction. However, its role in the reproductive axis in male animals remains to be understood. Here, we found that nesfatin-1 was mainly distributed in the arcuate nucleus (ARC), paraventricular nucleus (PVN), periventricular nucleus (PeN), and lateral hypothalamic area (LHA) of the hypothalamus; adenohypophysis and Leydig cells in male rats. Moreover, the concentrations of serum nesfatin-1 and its mRNA in hypothalamo-pituitary-gonadal axis (HPGA) vary with the age of the male rat. After intracerebroventricular injection of nesfatin-1, the hypothalamic genes for gonadotrophin releasing hormone (GnRH), kisspeptin (Kiss-1), pituitary genes for follicle-stimulate hormone β(FSHβ), luteinizing hormone β(LHβ), and genes for testicular steroidogenic acute regulatory (StAR) expression levels were decreased significantly. Nesfatin-1 significantly increased the expression of genes for 3β-hydroxysteroid dehydrogenase (3β-HSD), 17β-hydroxysteroid dehydrogenase (17β-HSD), and cytochrome P450 cleavage (P450scc) in the testis of pubertal rats, but their levels decreased in adult rats (P < 0.05), along with the serum FSH, LH, and testosterone (T) concentrations. After nesfatin-1 addition in vitro, T concentrations of the supernatant were significantly higher than that in the control group. These results were suggestive of the role of nesfatin-1 in the regulation of the reproductive axis in male rats.

Obesity and related consequences to ageing

Obesity has become a major public health problem. Given the current increase in life expectancy, the prevalence of obesity also raises steadily among older age groups. The increase in life expectancy is often accompanied with additional years of susceptibility to chronic ill health associated with obesity in the elderly. Both obesity and ageing are conditions leading to serious health problems and increased risk for disease and death. Ageing is associated with an increase in abdominal obesity, a major contributor to insulin resistance and the metabolic syndrome. Obesity in the elderly is thus a serious concern and comprehension of the key mechanisms of ageing and age-related diseases has become a necessary matter. Here, we aimed to identify similarities underlying mechanisms related to both obesity and ageing. We bring together evidence that age-related changes in body fat distribution and metabolism might be key factors of a vicious cycle that can accelerate the ageing process and onset of age-related diseases.

Regulation of NUCB2/nesfatin-1 production in rat's stomach and adipose tissue is dependent on age, testosterone levels and lactating status

Nesfatin-1, which is derived from the NEFA/nucleobindin 2 (NUCB2) precursor, was recently identified as an anorexigenic peptide that is produced in several tissues including the hypothalamus. Currently, no data exist regarding the regulation of NUCB2/nesfatin-1 production in peripheral tissues, such as gastric mucosa and adipose tissue, through different periods of development. The aim of the present work was to study the variations on circulating levels, mRNA expression and tissue content in gastric mucosa and adipose tissue of NUCB2/nesfatin-1 with age and specially in two clue periods of maturation, weaning and puberty. The weaning period affected NUCB2/nesfatin-1 production in gastric tissue. The testosterone changes associated with the initiation of puberty regulated NUCB2/nesfatin-1 production via adipose tissue and gastric NUCB2/nesfatin-1 production. In conclusion, the production of NUCB2/nesfatin-1 by the stomach and adipose tissue fluctuates with age to regulate energy homeostasis during different states of development.

Nesfatin-1 and its effects on different systems

Nesfatin-1 is a peptide secreted by peripheral tissues, central and peripheral nervous system. It is involved in the regulation of energy homeostasis related with food regulation and water intake. Nesfatin-1 can pass through the blood-brain barrier in both directions. It suppresses feeding independently from the leptin pathway and increases insulin secretion from pancreatic beta islet cells. That is why nesfatin-1 has drawn attention as a new therapeutic agent, especially for the treatment of obesity and diabetes mellitus. Its effects on nutrition have been studied in more detail in literature. On the other hand, its effects on other physiological parameters and mechanisms of action still need to be clarified. Synthesizing the research on nesfatin-1 can help us better understand this field. Hippokratia 2015, 19 (1): 4-10.

Non-steroidal anti-inflammatory drugs attenuate the vascular responses in aging metabolic syndrome rats

AIM

Metabolic syndrome (MS) and aging are low-grade systemic inflammatory conditions, and inflammation is a key component of endothelial dysfunction. The aim of this study was to investigate the effects of non-steroidal anti-inflammatory drugs (NSAIDs) upon the vascular reactivity in aging MS rats.

METHODS

MS was induced in young male rats by adding 30% sucrose in drinking water over 6, 12, and 18 months. When the treatment was finished, the blood samples were collected, and aortas were dissected out. The expression of COX isoenzymes and PLA2 in the aortas was analyzed using Western blot analysis. The contractile responses of aortic rings to norepinephrine (1 μmol/L) were measured in the presence or absence of different NSAIDs (10 μmol/L for each).

RESULTS

Serum levels of pro-inflammatory cytokines (IL-6, TNF-α, and IL-1β) in control rats were remained stable during the aging process, whereas serum IL-6 in MS rats were significantly increased at 12 and 18 months. The levels of COX isoenzyme and PLA2 in aortas from control rats increased with the aging, whereas those in aortas from MS rats were irregularly increased with the highest levels at 6 months. Pretreatment with acetylsalicylic acid (a COX-1 preferential inhibitor), indomethacin (a non-selective COX inhibitor) or meloxicam (a COX-2 preferential inhibitor) decreased NE-induced contractions of aortic rings from MS rats at all the ages, with meloxicam being the most potent. Acetylsalicylic acid also significantly reduced the maximum responses of ACh-induced vasorelaxation of aortic rings from MS rats, but indomethacin and meloxicam had no effect.

CONCLUSION

NSAIDs can directly affect vascular responses in aging MS rats. Understanding the effects of NSAIDs on blood vessels may improve the treatment of cardiovascular diseases and MS in the elders.

Angiotensin II and 1-7 during aging in Metabolic Syndrome rats. Expression of AT1, AT2 and Mas receptors in abdominal white adipose tissue

Renin-Angiotensin System (RAS) plays an important role in the development of Metabolic Syndrome (MS) and in aging. Angiotensin 1-7 (Ang 1-7) has opposite effects to Ang II. All of the components of RAS are expressed locally in adipose tissue and there is over-activation of adipose RAS in obesity and hypertension. We determined serum and abdominal adipose tissue Ang II and Ang 1-7 in control and MS rats during aging and the expression of AT1, AT2 and Mas in white adipose tissue. MS was induced by sucrose ingestion during 6, 12 and 18 months. During aging, an increase in body weight, abdominal fat and dyslipidemia were found but increases in aging MS rats were higher. Control and MS concentrations of serum Ang II from 6-month old rats were similar. Aging did not modify Ang II seric concentration in control rats but decreased it in MS rats. Ang II levels increased in WAT from both groups of rats. Serum and adipose tissue Ang 1-7 increased during aging in MS rats. Western blot analysis revealed that AT1 expression increased in the control group during aging while AT2 and Mas remained unchanged. In MS rats, AT1 and AT2 expression decreased significantly in aged rats. The high concentration of Ang 1-7 and adiponectin in old MS rats might be associated to an increased expression of PPAR-γ. PPAR-γ was increased in adipose tissue from MS rats. It decreased with aging in control rats and showed no changes during aging in MS rats. Ang 1-7/Mas axis was the predominant pathway in WAT from old MS animals and could represent a potential target for therapeutical strategies in the treatment of MS during aging.