Effect of Ramadan fasting on serum concentration of apelin-13 and new obesity indices in healthy adult men

Is Habitual Dietary Intake of Fats Associated with Apelin Gene Expression in Visceral and Subcutaneous Adipose Tissues and Its Serum Levels in Obese Adults?

INTRODUCTION

Apelin could be one of the last protective defenses before developing obesity-related disorders, including insulin resistance, type 2 diabetes, and hypertension, which can be modified by dietary intake. The present study investigated the association of habitual intake of total fatty acids (TFAs), saturated-, monounsaturated-, polyunsaturated FAs, n-3, and n-6 FAs with Apelin expression in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT).

METHODS

We obtained VAT and SAT from 168 participants (64 nonobese and 104 obese) who had undergone open abdominal surgery. Dietary intake information was gathered with a valid and reliable food frequency questionnaire. The mRNA expression of the Apelin gene was analyzed by real-time PCR.

RESULTS

Apelin serum levels were increased in the obese subjects compared to the nonobese group (p = 0.016). The SAT and VAT Apelin mRNA levels were significantly elevated in the obese participants compared to the nonobese ones (p < 0.05). Based on BMI status, only obese subjects indicated a positive association between SAT and VAT Apelin expression and TFA intake (p < 0.001). However, this association was observed between SAT and VAT Apelin gene expression and polyunsaturated fatty acid (PUFA) and n-3 FA intakes in both obese and nonobese groups (p < 0.05).

CONCLUSION

High Apelin gene expression was associated with TFA intake in obese subjects in both fat tissues. However, habitual intake of PUFA and n-3 FA was associated with Apelin gene expression in obese and nonobese individuals. Our results indicate a determinative role of the quality and quantity of FA intake on adipose tissue.

Exergaming During Ramadan Intermittent Fasting Improve Body Composition as Well as Physiological and Psychological Responses to Physical Exercise in Adolescents With Obesity

The effects of exergaming on biochemical responses has been investigated; however, no data is available for this effect during Ramadan intermittent fasting (RIF). RIF is a daily fasting characterized by abstaining from eating and drinking from sunrise to sunset for 29–30 days. The purpose of this study was to investigate the effect of exergaming during RIF on body composition, physical performance and hematological parameters in overweight and adolescents with obesity. Twenty-four adolescents with obesity were divided into two groups [control group (CG), n = 12, or cooperative sport exergaming group (EG), n = 12: 45 min per session during five days per week)]. Participants completed a 6-min walking test (6MWT), a squat jump test and a 10 and a 30m sprint tests in four different occasions: before Ramadan (T0), the second week of Ramadan (T1), the fourth week of Ramadan (T2), and after Ramadan (T3). Blood pressure, rating of perceived exertion (RPE), body composition, central obesity index, dietary intake and profile of mood states (POMS) were, also, assessed over the four periods. The results showed that body weight, body mass index and body fat percentage were significantly lower at T2 compared to T0 and T1 in the EG. After RIF, body composition returned to the values recorded before RIF. The POMS score was significantly lower during T2 compared to T0, T1 and T3 in the EG. The vertical jump and the 6MWT distance were significantly higher (i) at T2 compared to T0, T1 and T3 in the EG and (ii) in EG compared to CG at T2. RPE was significantly lower (i) at T2 compared to T0, T1 and T3 in the EG and (ii) in EG compared to CG at T2. Blood pressure was lower during T2 compared to the other periods in EG. The EG experienced significant decreases in total cholesterol and triglycerides during T2. However, no significant changes between groups and periods was reported for all the other parameters. In conclusion, exergaming during RIF has a positive effect on body composition and physiological and psychological responses in adolescents with obesity.

Effect of Ramadan fasting on hepatic steatosis as quantified by controlled attenuation parameter (CAP): a prospective observational study

Background

Although Ramadan fasting has a beneficial effect on health, the role of Ramadan fasting on patients with non-alcoholic fatty liver disease (NAFLD), as quantified by the controlled attenuation parameter (CAP), is not determined yet. So, this study aimed to determine the effect of Ramadan fasting on patients with NAFLD by assessing the controlled attenuation parameter (CAP) and biochemical parameters of the fatty liver.

Patients and methods

A prospective observational study was conducted on 40 NAFLD patients, who were diagnosed by ultrasonography and quantified with controlled attenuation parameter (CAP) in transient elastography (FibroScan) and fasted the month of Ramadan. Transient elastography for CAP and liver stiffness measurement (LSM) were performed. Fibrosis 4 score (FIB4) and NAFLD fibrosis score (NFS) were also calculated.

Results

There is a statistically significant change in body mass index, fasting blood glucose, HbA1c, triglycerides, LDL cholesterol, HDL cholesterol, total cholesterol, serum albumin, total protein, AST, ALT, and alkaline phosphatase after Ramadan fasting. There were significant clinical improvements after Ramadan fasting in FIB-4 (1.31 ± 0.26 and 1.24 ± 0.25 respectively, p < 0.001), CAP (318.52 ± 34.59 and 294.0 ± 20.34, respectively, p < 0. 001), and LSM (6.95 ± 1.62 and 6.59 ± 1.49, respectively, p < 0. 001).

Conclusion

Our study demonstrates that Ramadan fasting could improve liver steatosis in patients with NAFLD proved with a significant reduction in the CAP and LSM.

Fasting, Nutrition and Weight Loss: An Approach to Refine Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is considered as one of the most common causes of chronic liver disease. It includes a group of conditions associated with fat deposition in liver cells. Also, NAFLD is strongly associated with obesity and insulin resistance (IR). Until now, there is no pharmacological treatment validated for this disease. Fasting, nutritional intervention, and weight loss can be considered the first line in treating hepatic steatosis. This review is based on the scientific evidence showing the results of these interventions in the past years. The results include fasting and nutritional support for NAFLD treatment in humans. In clinical trials and cohort studies, an increase in hepatic fat content was correlated with a weight loss of at least 7% and a diet resembling the Mediterranean diet (MD) improving hepatic biomarkers and histological regression of NAFLD. Fasting is a dietary approach known to improve the lipid profile in healthy and obese populations by decreasing overall cholesterol, triglycerides, LDL, and increasing HDL. Bariatric surgery helps improve liver fat content in patients with serious health problems due to overweight.

Adipokines, Myokines, and Cardiokines: The Role of Nutritional Interventions

It is now established that adipose tissue, skeletal muscle, and heart are endocrine organs and secrete in normal and in pathological conditions several molecules, called, respectively, adipokines, myokines, and cardiokines. These secretory proteins constitute a closed network that plays a crucial role in obesity and above all in cardiac diseases associated with obesity. In particular, the interaction between adipokines, myokines, and cardiokines is mainly involved in inflammatory and oxidative damage characterized obesity condition. Identifying new therapeutic agents or treatment having a positive action on the expression of these molecules could have a key positive effect on the management of obesity and its cardiac complications. Results from recent studies indicate that several nutritional interventions, including nutraceutical supplements, could represent new therapeutic agents on the adipo-myo-cardiokines network. This review focuses the biological action on the main adipokines, myokines and cardiokines involved in obesity and cardiovascular diseases and describe the principal nutraceutical approaches able to regulate leptin, adiponectin, apelin, irisin, natriuretic peptides, and follistatin-like 1 expression.

Effects of Time-Restricted Feeding during Ramadan on Dietary Intake, Body Composition and Metabolic Outcomes

Ramadan fasting is a form of time-restricted feeding which combines a fast and feast period daily for a duration of one month every year. During Ramadan, Muslims abstain from food and drink consumption from dawn till sunset and this change in the meal schedule and frequency results in significant changes to the composition of the diet, such as energy and nutrient intake. These changes in dietary habits and their corresponding effects on cardiometabolic disease risk are compiled in this review. Ramadan fasting shows limited benefits to body composition via reductions in body mass in both healthy and obese individuals, although the results are often found to be transient and heterogeneous. There is, however, a more consistent improvement in blood lipid profile during Ramadan fasting, which often lasts beyond the Ramadan period. The results for glucose homeostasis, on the contrary, are more conflicting and inconclusive. The heterogeneity in the findings from the various studies can be generally attributed to cultural variations in dietary habits, differences in the duration of fasting due to seasonal/climatic differences at various geographical locations, age, gender and socioeconomic status, as well as other health and lifestyle factors of the various study populations.

Ramadan Intermittent Fasting Affects Adipokines and Leptin/Adiponectin Ratio in Type 2 Diabetes Mellitus and Their First-Degree Relatives

Background

In view of the association of Ramadan intermittent fasting with profound changes in lifestyle both in nondiabetic and diabetic patients, the aim of this study was to investigate the effect of Ramadan fasting on adiponectin, leptin and leptin to adiponectin ratio (LAR), growth hormone (GH), human-sensitive C-reactive protein (hs-CRP), and diabetic and metabolic syndrome factors in patients with Type 2 Diabetes Mellitus (Type 2 DM), their first-degree relatives (FDRs), and healthy controls.

Methods

This cohort study involved 98 Yemeni male subjects aged 30-70 years old: 30 Type 2 DM, 37 FDRs of Type 2 diabetic patients, and 31 healthy control subjects. Subjects' body mass index (BMI), waist circumference (WC), and blood pressure (BP) were measured, and venous blood samples were collected twice: the first samples were collected a couple of days prior to Ramadan fasting (baseline) and the second samples after 3 weeks of fasting.

Results

Ramadan fasting did not affect BMI, WC, and BP in Type 2 DM and their FDRs with respect to the baseline levels prior to Ramadan, whereas triglyceride and cholesterol were borderline significantly decreased in Type 2 DM with no effect in FDRs. Fasting blood glucose was not affected in Type 2 DM but was significantly increased in FDRs and control groups, whereas glycated haemoglobin (HbA1c) was slightly decreased in Type 2 DM, FDRs, and healthy controls. C-peptide, insulin, and insulin resistance (HOMA-IR) were significantly increased in Type 2 DM and FDRs, with no effect in the control group, whereas β-cell function (HOMA-β) was significantly decreased in FDRs and controls with no change in Type 2 DM. Ramadan fasting significantly decreased GH in both FDRs and control groups, and significantly increased hs-CRP in the control with no effect in Type 2 DM and FDRs. Adiponectin was significantly decreased, and leptin and LAR were significantly increased in Type 2 DM, FDRs, and control groups.

Conclusion

Ramadan intermittent fasting decreased adiponectin and increased leptin, LAR, insulin, and insulin resistance in both Type 2 DM and FDRs as well as decreased GH in both FDRs and healthy controls and increased hs-CRP in healthy controls. Moreover, Ramadan intermittent fasting neither worsens a patient's glycemic parameters nor improves it, with the exception of a slight improvement in HbA1c in Type 2 DM, FDRs, and healthy controls.

A systematic review, meta-analysis, and meta-regression of the impact of diurnal intermittent fasting during Ramadan on glucometabolic markers in healthy subjects

AIM

Studies on the effect of Ramadan diurnal intermittent fasting (RDIF) on glucometabolic markers have yielded conflicting results. We conducted ameta-analysis to estimate the effect size for changes in glucometabolic markers in healthy, non-athletic Muslims during Ramadan, and to assess the effect of variable covariates using meta-regression.

METHODS

CINAHL, Cochrane, EBSCOhost, EMBASE, Google Scholar, ProQuest Medical, PubMed/MEDLINE, ScienceDirect, Scopus, and Web of Science databases were searched from date of inceptionto January 2020. The glucometabolic markers analyzed were: fasting glucose (FG), insulin, insulin resistance (HOMA-IR), leptin, and adiponectin.

RESULTS

We identified seventy-two studies (3134 participants in total) that were conducted in 22 countries between 1982 and 2020. RDIF-induced effect sizes for the glucometabolic markers were: FG (no. of studies K = 61, number of subjects N = 2743, Hedges'g = -0.102, 95% CI: -0.194, -0.01); serum insulin (K = 16, N = 648, Hedges'g = 0.030 95% CI: -0.165, 0.226); HOMA-IR (K = 10, N = 349, Hedges'g = -0.012, 95% CI: -0.274, 0.250); leptin (K = 13, N = 442, Hedges'g = -0.010, 95% CI: -0.243, 0.223); and adiponectin (K = 11, N = 511, Hedges'g = 0.034, 95% CI: -0.227, 0.296).

CONCLUSION

RDIF imposes no adverse metabolic impacts, and might help in improving some glucometabolic markers in healthy subjects.

Ramadan fasting improves liver function and total cholesterol in patients with nonalcoholic fatty liver disease

Abstract. Background: Nonalcoholic fatty liver disease (NAFLD) is a serious global health problem, thus the prevention and management of the disease is necessary. This study aimed to determine the effects of Ramadan Fasting (RF) on liver function, Visceral Adiposity Index (VAI) and Atherogenic Index of Plasma (AIP) in these patients.

Methods: Eighty-three NAFLD patients (57 males and 26 females) were enrolled in the study, 42 patients who practiced RF, between Jun 18 through July 17, 2015 and 41 patients in non-fasting groups. Anthropometric parameters and Ultrasound grading were measured before and after Ramadan. The biochemical parameters including lipid profiles (total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides), liver enzymes (Aspartate aminotransferase, SGOT and Alanine aminotransferase, SGPT) were evaluated before and after Ramadan. AIP and VAI were calculated based on formula.

Results: The mean decreases in anthropometric indices were significantly different between groups. Similarly, the mean decrease in the total cholesterol values in the fasting group was remarkably greater than in the control group (p = 0.02). The values of AIP and VAI decreased at the end of the study in both group and the mean of changes showed no differences between groups (p = 0.79 and p = 0.65 for AIP and VAI, respectively). The changes in the concentrations of liver enzymes, as well as the severity of hepatic steatosis, showed remarkable differences between groups (p = 0.03, p = 0.05, and p = 0.02 for SGOT and SGPT, and Liver steatosis, respectively).

Conclusion: RF improved liver steatosis in NAFLD patients and might be useful in the management of NAFLD.

Impact of Ramadan diurnal intermittent fasting on the metabolic syndrome components in healthy, non-athletic Muslim people aged over 15 years: a systematic review and meta-analysis

Studies on the impact of Ramadan diurnal intermittent fasting (RDIF) on the metabolic syndrome (MetS) components among healthy Muslims observing Ramadan month have yielded contradictory results. This comprehensive meta-analysis aimed to obtain a more stable estimate of the effect size of fasting during Ramadan on the MetS components, examine variability among studies, assess the generalisability of reported results and perform subgroup analyses for associated factors. We searched the CINAHL, Cochrane, EBSCOhost, Google Scholar, ProQuest Medical, PubMed/MEDLINE, ScienceDirect, Scopus and Web of Science databases for relevant studies published from 1950 to March 2019. The MetS components analysed were: waist circumference (WC), systolic blood pressure (SBP), fasting plasma/serum glucose (FG), TAG, and HDL-cholesterol. We identified eighty-five studies (4326 participants in total) that were conducted in twenty-three countries between 1982 and 2019. RDIF-induced effect sizes for the MetS components were: small reductions in WC (no. of studies K = 24, N 1557, Hedges' g = -0·312, 95 % CI -0·387, -0·236), SBP (K = 22, N 1172, Hedges' g = -0·239, 95 % CI -0·372, -0·106), FG (K = 51, N 2318, Hedges' g = -0·101, 95 % CI -0·260, 0·004) and TAG (K = 63, N 2862, Hedges' g = -0·088, 95 % CI -0·171, -0·004) and a small increase in HDL-cholesterol (K = 57, N 2771, Hedges' g = 0·150, 95 % CI 0·064, 0·236). We concluded that among healthy people, RDIF shows small improvement in the five MetS components: WC, SBP, TAG, FG and HDL.

Dietary glycemic index and dietary glycemic load is associated with apelin gene expression in visceral and subcutaneous adipose tissues of adults

Background

Apelin, as an adipokine, plays an important role in the pathogenesis of insulin resistance and type 2 diabetes. This study aimed to determine whether the quality and quantity of dietary carbohydrates were associated with apelin gene expression in subcutaneous and visceral adipose tissues.

Methods

In this cross-sectional study, 102 adults who underwent minor abdominal surgery were selected. Approximately 100 mg of subcutaneous and visceral adipose tissues were collected during the surgery to measure apelin gene expression. Anthropometric measurment, blood samples, and dietary intakes were collected before surgery. The dietary carbohydrate intake, glycemic index (GI), and glycemic load (GL) were determined.

Results

The average apelin concentration was 269.6 ± 98.5(pg/mL), and 16.3% of participants were insulin resistant. There was a correlation between insulin (p-value = 0.043), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR)(p-value = 0.045) and apelin gene expression in visceral adipose tissue. There was a positive association of apelin gene expression with dietary GI and GL after adjustment for age, sex, and waist circumference in visceral and subcutaneous adipose tissues(p < 0.05). Apelin gene expression in visceral(p = 0.002) and subcutaneous(p = 0.003) adipose tissues was directly associated with foods with a higher GI. There was no association between total carbohydrate intake and apelin gene expression in both visceral and subcutaneous adipose tissues.

Conclusions

Dietary GI and GL, not total carbohydrate intake, were positively associated with apelin gene expression in both visceral and subcutaneous adipose tissues. Future studies are warranted to illustrate the chronic and acute effect of carbohydrate quality on apelin homeostasis.

Electronic supplementary material

The online version of this article (10.1186/s12986-019-0389-9) contains supplementary material, which is available to authorized users.

Metabolic effects of Ramadan fasting in patients at high risk of cardiovascular diseases

Background and aim

The effects of Ramadan fasting on health are a little controversial. The present study is aimed at evaluating the metabolic effects on a group of 517 patients with ≥2 cardiovascular risk factors over a period running from 2012 to 2014.

Methods

Each patient was assessed at three visits: before, during, and after Ramadan. Demographical, clinical and biological tests were performed at each visit.

Results

Metabolically, we noted a significant and discrete rise in blood glucose level (+1.2 mmol/L), triglycerides (+0.3 mmol/L), cholesterol (+0.12 mmol/L) and creatinine (+3 µmol/L) during Ramadan. These disturbances decreased significantly after Ramadan. The same variations were observed among diabetics (n=323). However, there was a significant decrease in HbA1c after Ramadan (9.0% vs 7.6%, p<0.001). Our findings also revealed there was no significant correlation between variations of metabolic parameters and dietary intake. No acute metabolic incidents were reported during the study period.

Conclusion

The current study showed that Ramadan is responsible for a transient but well tolerated disturbance of metabolic parameters followed by a significant post-Ramadan improvement. These changes did not seem to be directly related to dietary intake.

Effect of Ramadan diurnal fasting on visceral adiposity and serum adipokines in overweight and obese individuals

AIM

Excessive visceral adiposity is a major risk factor for developing insulin resistance and systemic low-grade inflammation. Ramadan diurnal fasting (RDF) is a religious ritual practiced by more than one billion Muslim throughout the world. It has been considered as one of the most common types of complementary and integrative health practices. The aim of this study is to examine the impact of RDF on visceral adiposity, circulating adipokines and glucoregulatory markers in patients with overweight or obesity.

METHODS

Overweight and obese subjects (n = 61; 23 men and 38 women) were included in the study. Body weight, visceral fat tissue area (measured by 3D-MRI), glucoregulatory factors, serum adipokines concentrations, dietary intake, and physical activity were assessed one week before and at the end of the lunar month of Ramadan.

RESULTS

From baseline, body weight and visceral fat tissue area serum total cholesterol, triglycerides, HDL-cholesterol, and systolic blood pressure significantly decreased (P < 0.05 for each) at the end of Ramadan. The serum levels of adiponectin, IL-6, TNF-α, and IGF-1 significantly decreased (P < 0.05 for each), but serum visfatin, leptin, apelin, IL-10, and IL-10/IL-6 ratio significantly increased (P < 0.05 for each) at the end of Ramadan. Changes in visceral adiposity significantly correlated with changes in plasma glucose (r = 0.4, P < 0.5) and resistin (r = 0.44, P < 0.001) at the end of Ramadan.

CONCLUSION

RDF lowers visceral adiposity, body weight and variably affects adipokines without adversely affecting markers of glucose homeostasis in individuals with overweight or obesity.

Effect of Ramadan Fasting on Weight and Body Composition in Healthy Non-Athlete Adults: A Systematic Review and Meta-Analysis

Background: Ramadan involves one month of fasting from sunrise to sunset. In this meta-analysis, we aimed to determine the effect of Ramadan fasting on weight and body composition. Methods: In May 2018, we searched six databases for publications that measured weight and body composition before and after Ramadan, and that did not attempt to influence physical activity or diet. Results: Data were collected from 70 publications (90 comparison groups, 2947 participants). There was a significant positive correlation between starting body mass index and weight lost during the fasting period. Consistently, there was a significant reduction in fat percentage between pre-Ramadan and post-Ramadan in people with overweight or obesity (−1.46 (95% confidence interval: −2.57 to −0.35) %, p = 0.010), but not in those of normal weight (−0.41 (−1.45 to 0.63) %, p = 0.436). Loss of fat-free mass was also significant between pre-Ramadan and post-Ramadan, but was about 30% less than loss of absolute fat mass. At 2–5 weeks after the end of Ramadan, there was a return towards, or to, pre-Ramadan measurements in weight and body composition. Conclusions: Even with no advice on lifestyle changes, there are consistent—albeit transient—reductions in weight and fat mass with the Ramadan fast, especially in people with overweight or obesity.

The evidence of apelin has the bidirectional effects on feeding regulation in Siberian sturgeon (Acipenser baerii)

Apelin is a peptide, mainly produced in the brain, which participates in several physiologic effects. However, knowledge about the mechanism of appetite regulation in teleosts, including the role of apelin is not well understood. The aim of this study is to explore the effect of feeding status on the expression of apelin mRNA in the whole brain and the effects of injection of apelin on food intake in Siberian sturgeon (Acipenser baerii). In this study, we first cloned the apelin cDNA sequence of the Siberian sturgeon. We obtained a 1046-bp cDNA fragment, including a 237-bp open reading frame (ORF) that encoded 78 amino acids. Apelin was widely distributed in 11 tissues related to feeding regulation, with the highest expression in thewhole brain, followed by the spleen and trunk kidney. In addition, we measured the effects of periprandial (preprandial and postprandial) change, fasting and re-feeding on apelin mRNA expression in whole brain. The level of apelin mRNA was significantly decreased 1h after feeding. The results of the fasting experiment showed that the expression of apelin mRNA in the brain was significantly reduced after 1day of fasting but consistently increased throughout the 15-day food deprivation period. When the 15-day fasted fish were re-fed, apelin mRNA expression in the brain was significantly increased as compared to that of the control. These results suggest that apelin may play a bidirectional role in the regulation of food intake in the Siberian sturgeon. In order to further examine the effect of apelin on feeding regulation in Siberian sturgeons, acute and chronic intraperitoneal (i.p.) injection experiments were performed and food intakes were recorded. Results showed that acute i.p. injection of apelin-13 reduced food intake, however, chronic i.p. injection apelin-13 increased the food intake for 7days in Siberian sturgeons. In conclusion, our results show that apelin has a bidirectional effect on feeding regulation in Siberian sturgeons by acting as a satiety factor in short-term feeding regulation and a starvation factor in long-term feeding regulation.

Visceral adiposity index: an indicator of adipose tissue dysfunction

The Visceral Adiposity Index (VAI) has recently proven to be an indicator of adipose distribution and function that indirectly expresses cardiometabolic risk. In addition, VAI has been proposed as a useful tool for early detection of a condition of cardiometabolic risk before it develops into an overt metabolic syndrome. The application of the VAI in particular populations of patients (women with polycystic ovary syndrome, patients with acromegaly, patients with NAFLD/NASH, patients with HCV hepatitis, patients with type 2 diabetes, and general population) has produced interesting results, which have led to the hypothesis that the VAI could be considered a marker of adipose tissue dysfunction. Unfortunately, in some cases, on the same patient population, there is conflicting evidence. We think that this could be mainly due to a lack of knowledge of the application limits of the index, on the part of various authors, and to having applied the VAI in non-Caucasian populations. Future prospective studies could certainly better define the possible usefulness of the VAI as a predictor of cardiometabolic risk.