Vitamin C in the Treatment and/or Prevention of Obesity

Mechanistic correlation of molecular pathways in obesity-mediated stroke pathogenesis

Obesity, a prominent risk factor for the development of heart attacks and several cardiovascular ailments. Obesity ranks as the second most significant avoidable contributor to mortality, whereas stroke stands as the second leading cause of death on a global scale. While changes in lifestyle have been demonstrated to have significant impacts on weight management, the long-term weight loss remains challenging, and the global prevalence of obesity continues to rise. The pathophysiology of obesity has been extensively studied during the last few decades, and an increasing number of signal transduction pathways have been linked to obesity preclinically. This review is focused on signaling pathways, and their respective functions in regulating the consumption of fatty food as well as accumulation of adipose tissue, and the resulting morphological and cognitive changes in the brain of individuals with obesity. We have also emphasized the recent progress in the mechanisms behind the emergence of obesity, as elucidated by both experimental and clinical investigations. The mounting understanding of signaling transduction may shed light on the future course of obesity research as we move into a new era of precision medicine.

Vitamin C supplementation alleviates hypercortisolemia caused by chronic stress

The aim of this study was to determine whether ascorbic acid (AA) supplementation can lower plasma levels of Cortisol and dehydroepiandrosterone-sulphate (DHEA-S) in patients diagnosed with functional hypercortisolemia due to unspecified chronic stress. Study includes data from 69 female with elevations in the cortisol and DHEA-S levels. Duration of follow-up was 2 months. Patients were divided into 3 groups. Group I included patients 23 with elevated cortisol, Group II-patients 24 with elevated levels of both hormones, Group III- patients 22 with normal cortisol and increased DHEA-S. Each group was randomly divided into two subgroups. The first subgroup was prescribed 1000 mg daily oral dose of AA. The diet of the second subgroup were left unaltered. All patients have their hormones levels re-examined 2 months later. After 2 months of AA supplementation the mean levels of elevated plasma cortisol and DHEA-S decreased. In Group I the level of cortisol fell from 780 ± 57-446 ± 26 nmol/L, p = 0.000065 in Group II from 657 ± 47-515 ± 29 nmol/L, p = 0.005. The elevated levels of DHEA-S have also declined in patients from AA-treated subgroups (from 13.9 ± 1.6-9.9 ± 1.2, p = 0.0007 in Group II, and from 12.8 ± 1.0-7.8 ± 1.4, p = 0.003 in Group III). In untreated subgroups changes in hormone levels were insignificant. The study shows that female patients with functional hypercortisolemia or elevated levels of DHEA-S can be treated with AA to bring level of these hormones closer to a normal range.

Change in function and homeostasis of HPA axis: The role of vitamin family

With the improvement of living quality, people pay more and more attention to vitamin supplements. The vitamins in the daily diet can meet the needs of the body. Whether additional vitamin supplementation is necessary still needs to be further explored. Many studies have reported that vitamin deficiency and excessive vitamin supplementation could lead to abnormal development in the body or increase the risk of diseases. Here, we summarize the abnormal levels of vitamins can cause the homeostasis imbalance of hypothalamus-pituitary-adrenal (HPA) axis by affecting its development and function. It can lead to abnormal synthesis and secretion of glucocorticoid in the body, which mediates the occurrence and development of metabolic diseases and psychoneurotic diseases. In addition, vitamin has a strong antioxidant effect, which can eliminate oxygen free radicals. Thereby, vitamins can alter HPA axis function and homeostasis maintenance by combating oxidative stress. This review provides a theoretical basis for clarifying the role of abnormal levels of vitamin in the occurrence and development of multiple diseases and its intervention strategy, and also provides reference value and guiding significance for rational use of vitamins.

The Potential Effects of Dietary Antioxidants in Obesity: A Comprehensive Review of the Literature

Obesity has become a global health concern, with its prevalence steadily increasing in recent decades. It is associated with numerous health complications, including cardiovascular diseases, diabetes, and certain types of cancer. The aetiology of obesity is multifactorial, involving genetic, environmental, and lifestyle factors. In recent years, oxidative stress has emerged as a potential contributor to obesity and its related metabolic disorders. Dietary antioxidants, which can counteract oxidative stress, have gained significant attention for their potential role in preventing and managing obesity. This comprehensive review aims to explore the impact of dietary antioxidants on obesity and its associated metabolic dysregulations, discussing the underlying mechanisms and highlighting the potential therapeutic implications.

Antioxidants positively regulate obesity dependent circRNAs - sperm quality - functional axis

Obesity is a pathophysiological condition, dependent on body fat accumulation, that progressively induces systemic oxidative stress/inflammation leading to a set of associated clinical manifestations, including male infertility. CircRNAs, covalently closed RNA molecules, are key regulators of sperm quality. Recently, we have characterized a complete profile of high-fat diet (HFD) spermatic circRNA cargo, predicting paternal circRNA dependent networks (ceRNETs), potentially involved in sperm oxidative stress and motility anomalies. In the current work, using HFD C57BL6/J male mice, orally treated with a mix of bioactive molecules (vitamin C; vitamin B12; vitamin E; selenium-L-methionine; glutathione-GSH) for 4 weeks, a reversion of HFD phenotype was observed. In addition, the functional action of the proposed formulations on circRNA biogenesis was evaluated by assessing the endogenous spermatic FUS-dependent backsplicing machinery and related circRNA cargo. After that, spermatic viability and motility were also analyzed. Paternal ceRNETs, potentially involved in oxidative stress regulation and sperm motility defects, were identified and used to suggest that the beneficial action of the food supplements here conveniently formulated on sperm motility was likely due to the recovery of circRNA profile. Such a hypothesis was, then, verified by an in vitro assay.

Associations of oxidative balance score with total abdominal fat mass and visceral adipose tissue mass percentages among young and middle-aged adults: findings from NHANES 2011-2018

Objective

This study aimed to explore the association of the oxidative balance score (OBS) with total abdominal fat mass (TAFM) and visceral adipose tissue mass (VATM) percentages among young and middle-aged U.S. adults.

Methods

Young and middle-aged adults in the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018 were included. Analysis of variance and Rao-Scott adjusted chi-square tests were used to compare the characteristics across quartiles of OBS. Univariate and multivariate weighted logistic regression models were employed to explore the relationship between OBS and the risks of high TAFM or high VATM percentage in the general population and subgroups, while the interaction effects were tested with a likelihood test. Weighted restricted cubic spline analyses were utilized to assess the non-linear association of OBS with TAFM and VATM percentages.

Results

The final sample included 8,734 young and middle-aged non-institutionalized U.S. adults representing 134.7 million adults. Compared with adults in the first quartile of OBS, those with higher OBS were less likely to have a high TAFM percentage; the ORs and 95% CI for adults in the second, third, and highest quartiles of OBS were 0.70 (0.53-0.94), 0.49 (0.36-0.60), and 0.25 (0.18-0.36), respectively. Similar trends were observed in the association between OBS and VATM percentages. Moreover, similar effects were confirmed in the sensitivity analyses and subgroup analyses according to demographic characteristics. Regarding the OBS subclass, higher dietary OBS and lifestyle OBS were also correlated with decreased ORs of high TAFM and VATM percentages.

Conclusion

This study strongly suggests that higher OBS, as well as higher dietary OBS and lifestyle OBS, are significantly correlated with lower risks of abdominal obesity and visceral fat accumulation. The findings highlight the importance of an antioxidant-rich diet and maintaining a healthy lifestyle in reducing the risks.

Peppers and their constituents against obesity

Phytotherapy can be an efficient tool for prevention and treatment of disorders including obesity. The purpose of this narrative review is to summarize the available knowledge concerning the positive effects of peppers (Capsicum spp.) and their alkaloid capsaicin on human health, in particular on fat and obesity. Search for literature was performed in Medline/Pubmed, Web of Science and SCOPUS databases between the year 2000 and 2023. Words used to search were pepper, Capsicum, capsaicin, review, obesity, fat, weight loss and mechanisms. The available data demonstrate that both pepper extract and capsaicin can positively influence human health and treat several disorders. Moreover, they can reduce fat storage affecting brain centres responsible for the sensation of hunger, nutrient uptake by gastrointestinal tract, state of adipocytes, increase in carbohydrate and fat oxidation, metabolism and thermogenesis and other mechanisms. Therefore, despite some possible limitations, these substances could be useful for treatment of obesity.

A weighted quantile sum regression with penalized weights and two indices

Background

New statistical methodologies were developed in the last decade to face the challenges of estimating the effects of exposure to multiple chemicals. Weighted Quantile Sum (WQS) regression is a recent statistical method that allows estimating a mixture effect associated with a specific health effect and identifying the components that characterize the mixture effect.

Objectives

In this study, we propose an extension of WQS regression that estimates two mixture effects of chemicals on a health outcome in the same model through the inclusion of two indices, one in the positive direction and one in the negative direction, with the introduction of a penalization term.

Methods

To evaluate the performance of this new model we performed both a simulation study and a real case study where we assessed the effects of nutrients on obesity among adults using the National Health and Nutrition Examination Survey (NHANES) data.

Results

The method showed good performance in estimating both the regression parameter and the weights associated with the single elements when the penalized term was set equal to the magnitude of the Akaike information criterion of the unpenalized WQS regression. The two indices further helped to give a better estimate of the parameters [Positive direction Median Error (PME): 0.022; Negative direction Median Error (NME): -0.044] compared to the standard WQS without the penalization term (PME: -0.227; NME: 0.215). In the case study, WQS with two indices was able to find a significant effect of nutrients on obesity in both directions identifying sodium and magnesium as the main actors in the positive and negative association, respectively.

Discussion

Through this work, we introduced an extension of WQS regression that improved the accuracy of the parameter estimates when considering a mixture of elements that can have both a protective and a harmful effect on the outcome; and the advantage of adding a penalization term when estimating the weights.

The micronutrient content of the diet is correlated with serum glucose biomarkers and lipid profile and is associated with the odds of being overweight/obese-a case-control study

Background

A low micronutrient intake has been reported to contribute to the double-burden of obesity, increasing the risk for chronic diseases such as cardiovascular disease, diabetes, cancer, and mental disorders. This case-control study compared micronutrient intake profiles in overweight/obese vs. normal-weight individuals. We hypothesized that a low intake of certain micronutrients would increase the odds of being overweight/obese.

Methods

The case group (n = 812 adults) consisted of individuals with a BMI of ≥25  kg/m², and the control group (n = 793) had BMIs of 17.9-24.9  kg/m². A validated 124-item food frequency questionnaire was used to determine micronutrient-related dietary-quality, using the index of nutritional quality (INQ), calculated as the fraction of a micronutrient consumed vs. its dietary requirement. In addition, body surface area (BSA) was calculated according to the Mosteller formula.

Results

The control group had significantly higher INQ-scores of vitamin A, vitamin C, calcium, magnesium, and selenium compared to the case group. Furthermore, individuals with normal BSA (≤1.91 m² for men; ≤1.71  m² for women) had significantly higher INQ scores of vitamin C, calcium, magnesium, and zinc compared to participants with high BSA. In multivariable adjustment regression models, INQs of vitamin C (OR_BMI = 0.79, 95%CI: 0.64-0.97; OR_BSA = 0.81, 95%CI, 0.68-0.97) and magnesium (OR_BMI = 0.69, 95%CI: 0.47-0.99; OR_BSA = 0.71, 95%CI: 0.52-0.97) were significantly associated with the odds of obesity/overweight (in both BMI and BSA categories).

Conclusion

The significant association between micronutrient levels of the diet, especially of vitamin C and magnesium, with both obesity criteria, emphasized the importance of certain micronutrients in the obesity/overweight causal network.

Prospective Associations between Dietary Patterns and Abdominal Obesity in Middle-Aged and Older Korean Adults

This study aimed to identify major dietary patterns associated with abdominal obesity in middle-aged and older Korean adults. Data from the Korean Genome and Epidemiology Study were used. A total of 48,037 Korean adults aged ≥40 years without abdominal obesity at baseline were followed-up. Dietary assessment was conducted using a validated 106-item food-frequency questionnaire, and dietary patterns were identified using factor analysis. Abdominal obesity was defined as a waist circumference of ≥90 cm for men and ≥85 cm for women, according to the Korean Society for the Study of Obesity. Multivariable Cox proportional-hazards models were used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the future risk of abdominal obesity for each dietary pattern after adjusting for potential covariates. After an average follow-up of 4.89 years, we reported 5878 cases (1932 men and 3946 women) of abdominal obesity. Based on factor analysis, three major dietary patterns were identified in both men and women: the "healthy", "coffee and sweets", and "multi-grain" patterns. In the fully adjusted model, the "healthy" pattern was inversely associated with the incidence of abdominal obesity (HR for fourth vs. first quartile: 0.86; 95% CI: 0.75-0.98; p for trend = 0.0358 for men; HR for fourth vs. first quartile: 0.90; 95% CI: 0.83-0.99; p for trend = 0.0188 for women), whereas the "coffee and sweets" pattern was positively associated with it (HR for fourth vs. first quartile: 1.23; 95% CI: 1.08-1.40; p for trend = 0.0495 for men; HR for fourth vs. first quartile: 1.14; 95% CI: 1.04-1.25; p for trend = 0.0096 for women). In contrast, the "multi-grain" pattern in men and women showed no significant association with the incidence of abdominal obesity. Diets rich in colorful vegetables, seaweeds, mushrooms, tubers, fruits, soy products, and fish and low in coffee, sweets, and oils/fats might be favorable for reducing the future risk of abdominal obesity, particularly in middle-aged and older Korean adults.

Herbal medicine for the treatment of obesity-associated asthma: a comprehensive review

Obesity is fast growing as a global pandemic and is associated with numerous comorbidities like cardiovascular disease, hypertension, diabetes, gastroesophageal reflux disease, sleep disorders, nephropathy, neuropathy, as well as asthma. Studies stated that obese asthmatic subjects suffer from an increased risk of asthma, and encounter severe symptoms due to a number of pathophysiology. It is very vital to understand the copious relationship between obesity and asthma, however, a clear and pinpoint pathogenesis underlying the association between obesity and asthma is scarce. There is a plethora of obesity-asthma etiologies reported viz., increased circulating pro-inflammatory adipokines like leptin, resistin, and decreased anti-inflammatory adipokines like adiponectin, depletion of ROS controller Nrf2/HO-1 axis, nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) associated macrophage polarization, hypertrophy of WAT, activation of Notch signaling pathway, and dysregulated melanocortin pathway reported, however, there is a very limited number of reports that interrelates these pathophysiologies. Due to the underlying complex pathophysiologies exaggerated by obese conditions, obese asthmatics respond poorly to anti-asthmatic drugs. The poor response towards anti-asthmatic drugs may be due to the anti-asthmatics approach only that ignores the anti-obesity target. So, aiming only at the conventional anti-asthmatic targets in obese-asthmatics may prove to be futile until and unless treatment is directed towards ameliorating obesity pathogenesis for a holistic approach towards amelioration of obesity-associated asthma. Herbal medicines for obesity as well as obesity-associated comorbidities are fast becoming safer and more effective alternatives to conventional drugs due to their multitargeted approach with fewer adverse effects. Although, herbal medicines are widely used for obesity-associated comorbidities, however, a limited number of herbal medicines have been scientifically validated and reported against obesity-associated asthma. Notable among them are quercetin, curcumin, geraniol, resveratrol, β-Caryophyllene, celastrol, tomatidine to name a few. In view of this, there is a dire need for a comprehensive review that may summarize the role of bioactive phytoconstituents from different sources like plants, marine as well as essential oils in terms of their therapeutic mechanisms. So, this review aims to critically discuss the therapeutic role of herbal medicine in the form of bioactive phytoconstituents against obesity-associated asthma available in the scientific literature to date.

Associations of dietary antioxidant micronutrients with the prevalence of obesity in adults

Background

Antioxidant micronutrients have a therapeutic potential for clinical treatment of obesity. NO research, however, has examined the connection between the complex level of dietary antioxidants and obesity.

Materials and methods

We mainly aimed to investigate the relationship between a combination of antioxidants and obesity using the database of the national health and nutrition examination survey (NHANES). This cross-sectional study contains a survey of 41,021 people (≥18 years) in total ranging from 2005 to 2018. Multivariate logistic and weighted quantile sum (WQS) regression were performed to investigate the associations between these antioxidants, both individually and collectively, and the prevalence of obesity. The restricted cubic spline (RCS) regression was also utilized to analyze the linearity of these associations.

Results

According to multivariate logistic models, we found that the levels of most antioxidants in the highest quartile were independently related to a lower prevalence of obesity, while a reverse result was observed in selenium (p for trend <0.05). The WQS index revealed that a total of the 11 antioxidants is negatively related to the prevalence of obesity and abdominal obesity (all p<0.001), and iron/vitamin C have the greatest weight in the negative associations between antioxidant complex and obesity, as well as abdominal obesity. In addition, the RCS regression showed that retinol, vitamin A, α-carotene, β-carotene, β-cryptoxanthin, vitamin C, iron, and copper all had a non-linear association with obesity. Threshold effect analysis demonstrated that the inflection points of retinol, vitamin A, α-carotene, β-carotene, β-cryptoxanthin, vitamin C, iron, and cooper were 235.57, 374.81, 58.89, 891.44, 30.70, 43,410.00, 11,240.00, and 990.00 μg/day, respectively.

Conclusion

Our study found that a high level of a complex of 11 dietary antioxidants is related to a lower prevalence of obesity and abdominal obesity, among this inverse associations iron and vitamin C have the greatest weight.

Pleiotropic Functions of Nitric Oxide Produced by Ascorbate for the Prevention and Mitigation of COVID-19: A Revaluation of Pauling's Vitamin C Therapy

Linus Pauling, who was awarded the Nobel Prize in Chemistry, suggested that a high dose of vitamin C (l-ascorbic acid) might work as a prevention or treatment for the common cold. Vitamin C therapy was tested in clinical trials, but clear evidence was not found at that time. Although Pauling's proposal has been strongly criticized for a long time, vitamin C therapy has continued to be tested as a treatment for a variety of diseases, including coronavirus infectious disease 2019 (COVID-19). The pathogen of COVID-19, SARS-CoV-2, belongs to the β-coronavirus lineage, which includes human coronavirus, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome (MERS). This review intends to shed new light on vitamin C antiviral activity that may prevent SARS-CoV-2 infection through the chemical production of nitric oxide (NO). NO is a gaseous free radical that is largely produced by the enzyme NO synthase (NOS) in cells. NO produced by upper epidermal cells contributes to the inactivation of viruses and bacteria contained in air or aerosols. In addition to enzymatic production, NO can be generated by the chemical reduction of inorganic nitrite (NO₂^-), an alternative mechanism for NO production in living organisms. Dietary vitamin C, largely contained in fruits and vegetables, can reduce the nitrite in saliva to produce NO in the oral cavity when chewing foods. In the stomach, salivary nitrite can also be reduced to NO by vitamin C secreted from the epidermal cells of the stomach. The strong acidic pH of gastric juice facilitates the chemical reduction of salivary nitrite to produce NO. Vitamin C contributes in multiple ways to the host innate immune system as a first-line defense mechanism against pathogens. Highlighting chemical NO production by vitamin C, we suggest that controversies on the therapeutic effects of vitamin C in previous clinical trials may partly be due to less appreciation of the pleiotropic functions of vitamin C as a universal bioreductant.

The association between vitamin C dietary intake and its serum levels with anthropometric indices: A systematic review and meta-analysis

BACKGROUND

studies showed inflammatory background of overweight and obesity. Prevalence of weight disorders has dramatically increased over the past few decades. Vitamin C is an antioxidant and may be associated with weight disorders. This study aims to systematically review the relationship between dietary and serum vitamin C levels with anthropometric indices.

METHODS

A systematic search was conducted in Medline database (PubMed), Scopus, Embase, Web of Science, Cochrane library and Google Scholar up to the end of August 2021. All observational studies that assessed the relationship between dietary or circulating vitamin C levels and body mass index (BMI) and waist circumference (WC) on adults were included. The quality of included studies was assessed using the National Institute of Health quality assessment tool.

RESULTS

Among 11,689 studies, 47 and 37 articles were included in the systematic review and meta-analysis, respectively. There was an inverse significant correlation between WC and serum vitamin C levels (r = -0.28, 95% CI: -0.35,-0.21, I² = 14.2%) and between BMI and serum vitamin C levels (r = -0.17, 95% CI: -0.25, -0.09, I² = 72.8%). Higher vitamin C consumption was significantly associated with lower BMI. There were no significant differences in serum vitamin C levels between normal-weight and overweight subjects, but serum vitamin C levels were significantly higher in obese subjects in comparison with normal-weight subjects.

CONCLUSION

Results showed that both dietary and serum vitamin C levels were inversely associated with BMI and WC. More well-designed clinical trials are needed to assess the effect of vitamin C supplementation in prevention and treatment of obesity.

Effects of dietary vitamins on obesity-related metabolic parameters

Type 2 diabetes mellitus (T2DM) is one of the leading causes of death worldwide. Genetic factors, some underlying medical conditions, and obesity are risk factors of T2DM. Unlike other risk factors which are non-modifiable, obesity is preventable and usually treatable, and is largely contributed by lifestyle factors. Management of these lifestyle factors may curb the development of T2DM and reduces T2DM prevalence. Dietary vitamins have been recommended as a lifestyle modification intervention to support obesity treatment. Vitamins correlate negatively with body weight, body mass index and body composition. Some of the vitamins may also have anti-adipogenic, anti-inflammatory and antioxidant effects. However, results from pre-clinical and clinical studies of the effects of vitamins on obesity are inconsistent. A clear understanding of the effects of vitamins on obesity will help determine dietary intervention that is truly effective in preventing and treating obesity as well as obesity-related complications including T2DM. This article reviews existing evidences of the effects of vitamin supplementation on obesity and obesity-related metabolic status.

The relationship between food quality score with inflammatory biomarkers, and antioxidant capacity in young women

Diet has the potential to decrease oxidative stress and inflammation and this may be beneficial in several diseases. This study investigated the association between food quality score (FQS) with antioxidant and inflammatory properties in 171 apparently healthy young women. This cross-sectional study was conducted using a validated food frequency questionnaire to determine the dietary intake of participants. FQS was calculated by summing all the scores obtained from healthy and unhealthy food groups. The total antioxidant capacity and free radical scavenging activity of serum and urine were quantified using the ferric reducing/antioxidant power (FRAP) and α, α-diphenyl-β-picrylhydrazyl (DPPH) methods, respectively. Malondialdehyde (MDA) was measured using the formation of thiobarbituric acid reactive substances (TBARS). White blood cell (WBC) and neutrophil counts, mean platelet volume (MPV) and red blood cell distribution width (RDW), were measured. Neutrophil: lymphocyte ratio (NLR), platelet: lymphocyte ratio (PLR), and RDW: platelet ratio (RPR) were also calculated. A high food quality (rich in fruit and vegetables, nuts, whole grain, and low intake of sweetened beverage, potato chips and fried food from outside the home) was related to lower hematological inflammatory biomarkers including WBC count, RDW, NLR, and PLR. Multivariable-adjusted odds ratios (95% CIs) demonstrated that higher FQS group (third tertile vs. first tertile) was associated with a significant lower levels of urinary FRAP (ORadj  = 0.82; 95%CI: 0.70 to 0.97), and DPPH. High food quality was associated with reduced of markers of inflammation and oxidative stress in Iranian young girl.

Vitamin C attenuates predisposition to high-fat diet-induced metabolic dysregulation in GLUT10-deficient mouse model

Background

The development of type 2 diabetes mellitus (T2DM) is highly influenced by complex interactions between genetic and environmental (dietary and lifestyle) factors. While vitamin C (ascorbic acid, AA) has been suggested as a complementary nutritional treatment for T2DM, evidence for the significance and beneficial effects of AA in T2DM is thus far inconclusive. We suspect that clinical studies on the topic might need to account for combination of genetic and dietary factors that could influence AA effects on metabolism. In this study, we tested this general idea using a mouse model with genetic predisposition to diet-induced metabolic dysfunction. In particular, we utilized mice carrying a human orthologous GLUT10^G128E variant (GLUT10^G128E mice), which are highly sensitive to high-fat diet (HFD)-induced metabolic dysregulation. The genetic variant has high relevance to human populations, as genetic polymorphisms in glucose transporter 10 (GLUT10) are associated with a T2DM intermediate phenotype in nondiabetic population.

Results

We investigated the impacts of AA supplementation on metabolism in wild-type (WT) mice and GLUT10^G128E mice fed with a normal diet or HFD. Overall, the beneficial effects of AA on metabolism were greater in HFD-fed GLUT10^G128E mice than in HFD-fed WT mice. At early postnatal stages, AA improved the development of compromised epididymal white adipose tissue (eWAT) in GLUT10^G128E mice. In adult animals, AA supplementation attenuated the predisposition of GLUT10^G128E mice to HFD-triggered eWAT inflammation, adipokine dysregulation, ectopic fatty acid accumulation, metabolic dysregulation, and body weight gain, as compared with WT mice.

Conclusions

Taken together, our findings suggest that AA has greater beneficial effects on metabolism in HFD-fed GLUT10^G128E mice than HFD-fed WT mice. As such, AA plays an important role in supporting eWAT development and attenuating HFD-induced metabolic dysregulation in GLUT10^G128E mice. Our results suggest that proper WAT development is essential for metabolic regulation later in life. Furthermore, when considering the usage of AA as a complementary nutrition for prevention and treatment of T2DM, individual differences in genetics and dietary patterns should be taken into account.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12263-022-00713-y.

SMP30-mediated synthesis of vitamin C activates the liver PPARα/FGF21 axis to regulate thermogenesis in mice

The vitamin-C-synthesizing enzyme senescent marker protein 30 (SMP30) is a cold resistance gene in Drosophila, and vitamin C concentration increases in brown adipose tissue post-cold exposure. However, the roles of SMP30 in thermogenesis are unknown. Here, we tested the molecular mechanism of thermogenesis using wild-type (WT) and vitamin C-deficient SMP30-knockout (KO) mice. SMP30-KO mice gained more weight than WT mice without a change in food intake in response to short-term high-fat diet feeding. Indirect calorimetry and cold-challenge experiments indicated that energy expenditure is lower in SMP30-KO mice, which is associated with decreased thermogenesis in adipose tissues. Therefore, SMP30-KO mice do not lose weight during cold exposure, whereas WT mice lose weight markedly. Mechanistically, the levels of serum FGF21 were notably lower in SMP30-KO mice, and vitamin C supplementation in SMP30-KO mice recovered FGF21 expression and thermogenesis, with a marked reduction in body weight during cold exposure. Further experiments revealed that vitamin C activates PPARα to upregulate FGF21. Our findings demonstrate that SMP30-mediated synthesis of vitamin C activates the PPARα/FGF21 axis, contributing to the maintenance of thermogenesis in mice.

The Association between Index of Nutritional Quality (INQ) and Obesity: Baseline Data of Kharameh Cohort

Obesity is an increasing problem that can lead to noncommunicable diseases. The role of dietary factors on one's obesity is confirmed in many studies. One nutritional approach that can be used for assessment of the foods and diets is the Index of Nutritional Quality (INQ). Our study is aimed at exploring the association between INQ and obesity. Our hypothesis is that enriched and high-quality diets reduce the risk of overweight or obesity. This study was carried out on 6248 overweight and obese participants, from whom 4356 (69.7%) and 1892 (30.3%) were overweight and obese, respectively. To assess the dietary intake for the participants, a valid food frequency questionnaire (FFQ) with 130 food items was utilized. The analysis revealed an inverse association between the overweight and the INQ of iron, thiamin, riboflavin, B6, folate, zinc, magnesium, calcium, and vitamin C and E. For the obese group, this inverse association was found for iron, B6, folate, zinc, magnesium, calcium, and vitamin C and E. These results approved our hypothesis that a rich nutrition diet may lead to a lower risk of obesity.

Vitamin C protects against hypoxia, inflammation, and ER stress in primary human preadipocytes and adipocytes

Dysregulation of adipose tissue involves increased cellular hypoxia, ER stress, and inflammation and altered adipokine production, contributing to the aetiology of obesity-related diseases including type 2 diabetes and cardiovascular disease. This study aimed to investigate the effects of Vitamin C supplementation on these processes in primary human preadipocytes and adipocytes. Treatment of preadipocytes and adipocytes with the proinflammatory cytokine TNFα and palmitic acid (PA), to mimic the obesogenic milieu, significantly increased markers of hypoxia, ER stress and inflammation and reduced secretion of high molecular weight (HMW) adiponectin. Importantly, Vitamin C abolished TNFα+PA induced hypoxia and significantly reduced the increases in ER stress and inflammation in both cell types. Vitamin C also significantly increased the secretion of HMW adiponectin from adipocytes. These findings indicate that Vitamin C can reduce obesity-associated cellular stress and thus provide a rationale for future investigations.

Dietary and Antioxidant Vitamins Limit the DNA Damage Mediated by Oxidative Stress in the Mother-Newborn Binomial

During pregnancy, appropriate nutritional support is necessary for the development of the foetus. Maternal nutrition might protect the foetus from toxic agents such as free radicals due to its antioxidant content. In this study, 90 mothers and their children were recruited. DNA damage mediated by oxidative stress (OS) was determined by the levels of 8-hidroxy-2′-deoxyguanosine (8-OHdG) in the plasma of women and umbilical cord blood. The mothers and newborns were categorised into tertiles according to their 8-OHdG levels for further comparison. No relevant clinical differences were observed in each group. A strong correlation was observed in the mother−newborn binomial for 8-OHdG levels (Rho = 0.694, p < 0.001). In the binomial, a lower level of 8-OHdG was associated with higher consumption of calories, carbohydrates, lipids, and vitamin A (p < 0.05). In addition, the levels of 8-OHdG were only significantly lower in newborns from mothers with a higher consumption of vitamin A and E (p < 0.01). These findings were confirmed by a significant negative correlation between the 8-OHdG levels of newborns and the maternal consumption of vitamins A and E, but not C (Rho = −0.445 (p < 0.001), −0.281 (p = 0.007), and −0.120 (p = 0.257), respectively). Multiple regression analysis showed that the 8-OHdG levels in mothers and newborns inversely correlated with vitamin A (β = −1.26 (p = 0.016) and −2.17 (p < 0.001), respectively) and pregestational body mass index (β = −1.04 (p = 0.007) and −0.977 (p = 0.008), respectively). In conclusion, maternal consumption of vitamins A and E, but not C, might protect newborns from DNA damage mediated by OS.

Fruit juice and childhood obesity: a review of epidemiologic studies

Childhood obesity is a national epidemic, and many efforts have been made to understand its risk factors. The purpose of this review was to provide an updated account of the observational studies evaluating the relationship between 100% fruit juice intake and obesity in children and adolescents, and to highlight the major risk factors that may impact this relationship. PubMed and Scopus were searched for terms related to fruit juice and childhood obesity, and studies assessing 100% fruit juice intake in participants ≤ 19 years old, with obesity-related outcomes (BMI or adiposity), and published before March 9, 2021 were included. There were 17 prospective cohort and 14 cross-sectional studies included in the analysis. Overall, the evidence does not support a relationship between 100% fruit juice intake and measures of obesity in most children. There is some evidence to suggest a minor positive association in some overweight or very young children, but due to fundamental differences and limitations in methodology, further investigation is required. Significant gaps in literature on this topic exist particularly in regards to randomized clinical trials in children, and in studies in racially diverse populations.

Identification of the interactions between specific genetic polymorphisms and nutrient intake associated with general and abdominal obesity in middle-aged adults

BACKGROUND & AIMS

Comprehensive understanding of gene-diet interactions is necessary to establish proper dietary guidelines to prevent and manage general and abdominal obesity. We investigated the role of genetic variants and their interactions with general and abdominal obesity-associated nutrients using a largescale genome-wide association study of Korean adults.

METHODS

A total of 50,808 participants from a Korean genome and epidemiology study were included. Dietary intake was assessed using a food frequency questionnaire. Obesity was defined as a body mass index ≥25 kg/m². Abdominal obesity (AO) was defined as waist circumference ≥90 cm and 80 cm in males and females, respectively. Dietary nutrient intake was classified based on Korean Dietary Reference Intakes (DRIs). Odds ratios and 95% confidence intervals were calculated after adjusting for age, sex, exercise, smoking, alcohol drinking, total energy consumption, PC1, and PC2.

RESULTS

Among the individuals consuming fat (%) above DRI, carriers of Ca binding protein 39 (CAB39)- rs6722579 minor allele (A) have a higher risk of AO than those not carrying the SNP (odds ration [OR] = 3.73, p-value = 2.05e-07; interaction p-value = 1.80e-07). Among the individuals consuming vitamin C above DRI, carriers of carboxypeptidase Q (CPQ)- rs59465035 minor allele (T) have a lower risk of AO than those without that SNP (OR = 0.89, p-value = 1.44e-08; interaction p-value = 9.50e-06). The genetic association with obesity was stronger among individuals with a genetic variant rs4130113 near GHR gene region in those consume folate above DRI and with a genetic variant rs5760920 near CRYBB2 gene region in those consume vitamin B2 above DRI.

CONCLUSION

Our study results suggested that interactions of specific polymorphisms at loci and certain nutrients may influence obesity and abdominal obesity.

Oxidative stress and obesity

Obesity is a disease of excessive accumulation of adipose tissue due to an increased energy intake which is disproportionate to the energy expenditure in the body. The visceral adipose tissue in the obese accumulated in that way increases the risk of developing a number of metabolic and cardiovascular diseases. Disorders such as diabetes, dyslipidemia, inflammation, endothelial dysfunction and mitochondria can contribute to the development of oxidative stress, which is especially pronounced in the abdominal type of obesity. Obesity can induce systemic oxidative stress through a variety of biochemical mechanisms. Although ROS is generated in a large number of cells, mitochondria play a significant role in their intracellular production through the process of oxidative phosphorylation of the respiratory chain, and in fatty acid oxidation reactions. Oxidative stress is a unique link between the various molecular disorders present in the development of insulin resistance that plays a key role in the pathogenesis and progression of chronic metabolic, proinflammatory diseases. The progression of insulin resistance is also affected by inflammation. Both of these can be the cause and the consequence of obesity. The synthesis of the inflammatory mediators is induced by oxidative stress, thus bringing the inflammation and the oxidative stress into a very significant relation. This review aims to highlight recent findings on the role of oxidative stress in the pathogenesis of obesity, with special reference to the mechanisms that explain its occurrence.

Obesity and Maternal-Placental-Fetal Immunology and Health

Obesity rates in women of childbearing age is now at 29%, according to recent CDC reports. It is known that obesity is associated with oxidative stress and inflammation, including disruptions in cellular function and cytokine levels. In pregnant women who are obese, associated placental dysfunction can lead to small for gestational age (SGA) infants. More frequently, however, maternal obesity is associated with large for gestational age (LGA) newborns, who also have higher incidence of metabolic disease and asthma due to elevated levels of inflammation. In addition, anthropogenic environmental exposures to "endocrine disrupting" and "forever" chemicals affect obesity, as well as maternal physiology, the placenta, and fetal development. Placental function is intimately associated with the control of inflammation during pregnancy. There is a large amount of literature examining the relationship of placental immunology, both cellular and humoral, with pregnancy and neonatal outcomes. Cells such as placental macrophages and NK cells have been implicated in spontaneous miscarriage, preeclampsia, preterm birth, perinatal neuroinflammation, and other post-natal conditions. Differing levels of placental cytokines and molecular inflammatory mediators also have known associations with preeclampsia and developmental outcomes. In this review, we will specifically examine the literature regarding maternal, placental, and fetal immunology and how it is altered by maternal obesity and environmental chemicals. We will additionally describe the relationship between placental immune function and clinical outcomes, including neonatal conditions, autoimmune disease, allergies, immunodeficiency, metabolic and endocrine conditions, neurodevelopment, and psychiatric disorders.

The correlation between serum inflammatory, antioxidant, glucose handling biomarkers, and Dietary Antioxidant Index (DAI) and the role of DAI in obesity/overweight causation: population-based case-control study

BACKGROUND

Obesity is a multifactorial disease, and about 40% of world adults are overweight, and about 20% are obese. Diet is one of the most important factors in the causality of obesity. The interactions between the diet and gut microbiota or chronic inflammation pathways highlight the importance of its various aspects in the incidence and prevalence of obesity. At the same time, diet is a combination of several antioxidants that are needed together for the body's antioxidant system. The Dietary Antioxidant Index (DAI) is a valid nutritional tool, and its correlation has been studied concerning total antioxidant capacity and malondialdehyde. The study aimed to examine the relationship between the DAI and the odds of obesity. We hypothesized that a higher DAI score indicating a predominantly antioxidant diet has a protective effect against odds of obesity.

METHODS

In this population-based case-control study, 812 participants with a higher body mass index (BMI) than 25 were selected as the case group. Also, 793 participants with BMI in the range of 17.9-24.9 were selected as the control group. A valid and reliable 124-item food frequency questionnaire (FFQ) was used to assess dietary intake. Based on FFQ data, we summed up the standardized intake of the major dietary antioxidants, including vitamin A, E, C, selenium, zinc, and manganese, to calculate DAI.

RESULTS

In a multivariable adjusting model, there was a significant association between DAI (as a continuous variable) and BMI (odds ratio (OR) = 0.95; 95% CI: 0.92-0.99; P value = 0.02). Also, there was a significant association between DAI (as a categorized variable) and body surface area with multivariable adjusting model (OR = 0.79; 95% CI: 0.64-0.98; P value = 0.04).

CONCLUSION

In conclusion, the DAI can accurately predict some serum antioxidant and anti-inflammatory levels along with glucose handling markers.

Association between dietary patterns and glycaemic control in a middle-aged Chinese population

OBJECTIVE

The present work was performed to analyse the association of dietary patterns with glycaemic control (Hb A1c < 7 %) in a large group of Chinese adults aged between 45 and 59 years.

DESIGN

Habitual dietary intakes in the preceding 12 months were assessed by well-trained interviewers using a validated semi-quantitative FFQ. Factor analysis with principal component method was used to obtain the dietary patterns, and the associations between dietary patterns and glycaemic control were determined using multivariable logistic regression models. Poor glycaemic control was defined as HbA1c ≥ 7·0.

SETTING

Despite decades of research, data on the relationship between dietary patterns and glycaemic control (HbA1c < 7 %) in China are sparse.

PARTICIPANTS

A total of 1739 participants aged 45-59 years from Hangzhou were included in the final analysis.

RESULTS

Three dietary patterns were ascertained and labelled as traditional southern Chinese, Western and grains-vegetables patterns. After controlling of the possible confounders, participants in the highest quartile of Western pattern scores had greater OR for HbA1c ≥ 7·0 (OR = 1·05; (95 % CI 1·000, 1·095); P = 0·048) than did those in the lowest quartile. Compared with those in the lowest quartile of grains-vegetables pattern, participants in the highest quartile had lower OR for HbA1c ≥ 7·0 (OR = 0·82; (95 % CI 0·720, 0·949); P = 0·038). Besides, no significant relationship between the traditional southern Chinese pattern and HbA1c ≥ 7·0 was observed (P > 0·05).

CONCLUSIONS

This study indicated that the Western pattern was associated with a higher risk, and the grains-vegetables pattern was associated with a lower risk for HbA1c ≥ 7·0. Future prospective studies are needed to confirm our findings.

Associations between fruit juice and milk consumption and change in BMI in a large prospective cohort of U.S. adolescents and preadolescents

BACKGROUND

There are concerns that fruit juice and milk contribute to childhood obesity.

OBJECTIVE

Determine the relationship between fruit juice and milk intakes and body mass index (BMI) change among preadolescents/adolescents.

METHODS

Participants aged 9 to 16 years old from the Growing Up Today Study II completed surveys including validated food frequency questionnaires in 2004, 2006 and 2008. The contributions of one serving of juice or milk to total energy intake and 2-year change in BMI were evaluated using multiple linear regression. Additional analyses were conducted with subgroups of juice (orange juice and other fruit juice) and milk (low fat and high fat). Missing values for BMI were imputed using a multiple imputation approach, after which data from 8173 participants and 13 717 2-year interval observations were analysed.

RESULTS

Baseline fruit juice consumption was inversely associated with BMI change in girls (β = -.102 kg/m² , SE = 0.038, P value = .008) but not boys after controlling for race, age, baseline BMI, and baseline and 2-year changes in total energy intake and physical activity. Orange juice was inversely associated with BMI change among girls (β = -.137 kg/m² , SE = 0.053, P value = .010) while other fruit juice, low fat and high fat milk were not associated with BMI change.

CONCLUSION

Orange juice was inversely associated with 2-year BMI change among preadolescent/adolescent girls but not boys and there were no significant associations with other juices or milk among either gender.

Micronutrient supplementation in pregnancies following bariatric surgery: a practical review for clinicians

Patients who have undergone bariatric surgery are at high risk for nutritional deficiencies before and after surgery if no proper supplementation and close follow-up are maintained. As pregnancies after these surgeries are occurring more frequently, deficiencies imply risks for both mother and child. Nutritional needs for this specific population are different from that of patients with obesity or a non-bariatric population. This review provides a comprehensive summary of the most described vitamins and minerals during pregnancy, after bariatric surgery, and during pregnancy after bariatric surgery in order to summarize their specific needs and possible side effects and to provide a useful guideline to the involved caregivers.

Index of Nutritional Quality (INQ) and the Risk of Obesity in Male Adolescents: a Case-Control Study

Dietary factors may play a key role in the etiology of obesity. The Index of Nutritional Quality (INQ) provides a comprehensive overview of the nutrients content of the diet. This study aimed to investigate the association between INQ and obesity in male adolescents. We hypothesize that receiving a high-quality diet reduces the risk of overweight or obese. This study was carried out on 214 obese/overweight as the case group and 321 normal-weight male adolescents as the control group. Dietary intakes of the participants were collected using a food frequency questionnaire (FFQ). The FFQ-derived dietary data were used to calculate the INQ scores. After adjustments for age and height, an inverse association was found between obesity and INQ of iron, vitamin B6, and magnesium, and a positive association was found between obesity and INQ of zinc (all P < 0.05). After further adjustments for nutritional knowledge and calorie intake, an inverse association was observed between obesity and INQ of vitamin C, iron, vitamin B6, pantothenic acid, selenium, and magnesium (all P < 0.05). The positive association of obesity and INQ of zinc remained significant after adjustments. A higher intake of vitamin C, iron, vitamin B6, pantothenic acid, selenium, and magnesium and a lower intake of zinc may be protective against adolescent obesity. More longitudinal studies are required to investigate the relationship between these nutrients and obesity.

Impact of Obesity-Induced Inflammation on Cardiovascular Diseases (CVD)

Overweight and obesity are key risk factors of cardiovascular disease (CVD). Obesity is currently presented as a pro-inflammatory state with an expansion in the outflow of inflammatory cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), alongside the expanded emission of leptin. The present review aimed to evaluate the relationship between obesity and inflammation and their impacts on the development of cardiovascular disease. A literature search was conducted by employing three academic databases, namely PubMed (Medline), Scopus (EMBASE), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). The search presented 786 items, and by inclusion and exclusion filterers, 59 works were considered for final review. The Newcastle–Ottawa Scale (NOS) method was adopted to conduct quality assessment; 19 papers were further selected based on the quality score. Obesity-related inflammation leads to a low-grade inflammatory state in organisms by upregulating pro-inflammatory markers and downregulating anti-inflammatory cytokines, thereby contributing to cardiovascular disease pathogenesis. Because of inflammatory and infectious symptoms, adipocytes appear to instigate articulation and discharge a few intense stage reactants and carriers of inflammation. Obesity and inflammatory markers are strongly associated, and are important factors in the development of CVD. Hence, weight management can help prevent cardiovascular risks and poor outcomes by inhibiting inflammatory mechanisms.

Oxidative Stress, Plant Natural Antioxidants, and Obesity

Oxidative stress is important in the pathophysiology of obesity, altering regulatory factors of mitochondrial activity, modifying the concentration of inflammation mediators associated with a large number and size of adipocytes, promoting lipogenesis, stimulating differentiation of preadipocytes to mature adipocytes, and regulating the energy balance in hypothalamic neurons that control appetite. This review discusses the participation of oxidative stress in obesity and the important groups of compounds found in plants with antioxidant properties, which include (a) polyphenols such as phenolic acids, stilbenes, flavonoids (flavonols, flavanols, anthocyanins, flavanones, flavones, flavanonols, and isoflavones), and curcuminoids (b) carotenoids, (c) capsaicinoids and casinoids, (d) isothiocyanates, (e) catechins, and (f) vitamins. Examples are analyzed, such as resveratrol, quercetin, curcumin, ferulic acid, phloretin, green tea, Hibiscus Sabdariffa, and garlic. The antioxidant activities of these compounds depend on their activities as reactive oxygen species (ROS) scavengers and on their capacity to prevent the activation of NF-κB (nuclear factor κ-light-chain-enhancer of activated B cells), and reduce the expression of target genes, including those participating in inflammation. We conclude that natural compounds have therapeutic potential for diseases mediated by oxidative stress, particularly obesity. Controlled and well-designed clinical trials are still necessary to better know the effects of these compounds.

Correlation of D-xylose with severity and morbidity-related factors of COVID-19 and possible therapeutic use of D-xylose and antibiotics for COVID-19

The SARS-Cov-2 pandemic that currently affects the entire world has been shown to be especially dangerous in the elderly (≥65 years) and in smokers, with notably strong comorbidity in patients already suffering from chronic diseases, such as Type 2 diabetes, cancers, chronic respiratory diseases, obesity, and hypertension. Inflammation of the lungs is the main factor leading to respiratory distress in patients with chronic respiratory disease and in patients with severe COVID-19. Several studies have shown that inflammation of the lungs in general and Type 2 diabetes are accompanied by the degradation of glycosaminoglycans (GAGs), especially heparan sulfate (HS). Several studies have also shown the importance of countering the degradation of HS in lung infections and Type 2 diabetes. D-xylose, which is the initiating element for different sulfate GAG chains (especially HS), has shown regeneration properties for GAGs. D-xylose and xylitol have demonstrated anti-inflammatory, antiglycemic, antiviral, and antibacterial properties in lung infections, alone or in combination with antibiotics. Considering the existing research on COVID-19 and related to D-xylose/xylitol, this review offers a perspective on why the association between D-xylose and antibiotics may contribute to significantly reducing the duration of treatment of COVID-19 patients and why some anti-inflammatory drugs may increase the severity of COVID-19. A strong correlation with scurvy, based on gender, age, ethnicity, smoking status, and obesity status, is also reviewed. Related to this, the effects of treatment with plants such as Artemisia are also addressed. CHEMICAL COMPOUNDS: D-xylose; xylitol; l-ascorbic Acid; D-glucuronic acid; N-acetylglucosamine; D-N-acetylglucosamine; N-acetylgalactosamine; galactose.

Clinical Impact Potential of Supplemental Nutrients as Adjuncts of Therapy in High-Risk COVID-19 for Obese Patients

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease (COVID-19) in China at the end of 2019 caused a major global pandemic and continues to be an unresolved global health crisis. The supportive care interventions for reducing the severity of symptoms along with participation in clinical trials of investigational treatments are the mainstay of COVID-19 management because there is no effective standard therapy for COVID-19. The comorbidity of COVID-19 rises in obese patients. Micronutrients may boost the host immunity against viral infections, including COVID-19. In this review, we discuss the clinical impact potential of supplemental nutrients as adjuncts of therapy in high-risk COVID-19 for obese patients.

Orange juice intake and anthropometric changes in children and adolescents

OBJECTIVE

Evaluate associations between orange juice (OJ) consumption and anthropometric parameters.

DESIGN

Prospective cohort study assessing the association between OJ intake and changes in BMI and height-for-age Z-score (HAZ) using mixed linear regression.

SETTING

2004-2008, USA.

PARTICIPANTS

Children from the Growing Up Today Study II (n 7301), aged 9-16 years at enrollment.

RESULTS

OJ consumption was positively associated with 2-year change in HAZ in girls (mean (se)): 0·03 (0·01) for non-consumers, 0·03 (0·02) for 1-3 glasses/month, 0·06 (0·01) for 1-6 glasses/week and 0·09 (0·02) for ≥1 glass/d after full adjustment (Ptrend = 0·02). However, OJ consumption was not associated with 2-year change in BMI percentile (kg/m2, mean (se)): -0·44 (0·36) for non-consumers, 0·20 (0·41) for 1-3 glasses/month, -0·04 (0·34) for 1-6 glasses/week and -0·77 (0·62) for ≥1 glass/d in girls, Ptrend = 0·81; -0·94 (0·53) for non-consumers, -1·68 (0·52) for 1-3 glasses/month, -0·81 (0·38) for 1-6 glasses per week and -1·12 (0·61) for ≥1 glass/d in boys, Ptrend = 0·49.

CONCLUSION

OJ consumption was favourably associated with height growth but unrelated to excess weight gain. OJ may be a useful alternative to whole fruit in the event that whole fruit intake is insufficient.

Nicotinamide and ascorbic acid nanoparticles against the hepatic insult induced in rats by high fat high fructose diet: A comparative study

AIMS

Non-alcoholic fatty liver disease (NAFLD) caused by consumption of high levels of fat and sugars (HFHS) in diet is considered one of the most dangerous medical complications among children and adolescents. Nicotinamide is among the promising candidates in ameliorating HFHS diet-induced NAFLD, but its use is limited by the possibility of prompting hepatotoxicity in high doses. Ascorbic acid is another promising candidate, however its use as a hepatoprotective agent is limited by its chemical instability. Therefore, the aim of the study was to overcome their delivery limitations and enhance their hepatoprotective activity by loading into nanoparticles.

KEY FINDINGS

In the present study, upon incorporating nicotinamide or ascorbic acid in chitosan nanoparticles, they ameliorated the insulin-resistant status induced in rats by a high-fat-high-fructose (HFHF) diet. Both formulae decreased serum level of ALT and AST, as well as liver tissue total cholesterol, triglycerides and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels. They also decreased oxidative and nitrosative stresses along with a significant increase in the hepatocellular energy. The biochemical findings were further confirmed by histopathological examination. Finally from the obtained data it could be concluded that chitosan nicotinamide nanoparticles at a dose level (10 mg/kg, p.o.) demonstrated beneficial pharmacological effect with safer toxicity profile than chitosan ascorbic acid nanoparticles.

SIGNIFICANCE

Nicotinamide chitosan nanoparticles could be recommended as daily supplement in the recovery from NAFLD.

Increased Oxidative Stress, Altered Trace Elements, and Macro-Minerals Are Associated with Female Obesity

Generally female individuals are more prone to obesity due to their lifestyle and physiology. However, female individuals have got little attention in this aspect. This pioneering study designed to find the level of serum malondialdehyde (MDA), non-enzymatic antioxidant (vitamin C), other trace elements (zinc and iron), and macro-minerals (sodium, potassium, and calcium) for female obesity determining its role and action in disease diagnosis along with propagation. For this prospective case-control study, 70 female obese and 70 healthy individuals were evaluated. Serum lipid peroxidation product malondialdehyde (MDA) concentration was measured to determine the level of lipid peroxidation. UV spectrophotometric method was implemented for vitamin C concentration to measure serum ascorbic acid. Atomic absorption spectroscopy (AAS) was implemented to determine serum macro-minerals (Na, K, and Ca), and trace elements (Zn and Fe) were estimated. For statistical analysis, student's t-test and Pearson's correlation test were executed. A significantly higher concentration of serum MDA (p < 0.001) and low concentration of antioxidants (vitamin C) (p < 0.001) are observed in patient than control group. We found a lower concentration of trace elements (zinc, iron) and macro-minerals (sodium, potassium, and calcium) in patients compared to control except sodium. The mean concentrations for serum Zn, Fe, Na, K, and Ca were 0.34 ± 0.01, 0.25 ± 0.01, 3828.91 ± 205.09, 90.42 ± 6.45, and 43.04 ± 2.38 mg/L and 0.78 ± 0.08, 0.84 ± 0.08, 2600.97 ± 99.79, 223.79 ± 14.64, and 86.43 ± 2.78 mg/L, respectively, for female obese patients and control subjects (p < 0.001). We can suggest from our study that there is a strong association of female obesity with increased serum concentrations of MDA and reduced non-enzymatic antioxidant vitamin C and different serum trace metals and macro-minerals.

A New Treatment for Local Adiposity with Ascorbic Acid and Ascorbyl-Palmitate Solution: Clinical and Histological Study

Background

Localized adiposity (AL) is the accumulation of subcutaneous adipose tissue, placed in definite anatomic areas, building up an alteration of the body silhouette. The aim of the present clinical and histological study is to assess the effectiveness of an injectable solution containing sodium salt of ascorbic acid 0.24% and surfactant agent at 0.020% ascorbyl-palmitate (SAP) for treating local adiposity.

Methods

Eighty healthy female adult patients were selected, suffering from local adiposity in the abdominal region. The patients underwent a cycle of 6 sessions, with biweekly treatments, without the addition of any active ingredient. Direct infiltration of pharmacologically active SAP solutions into the adipose tissue with a long needle, very similar to the needles used for spinal anesthesia, was performed. This procedure is quick and painless (does not require any anesthesia) with moderate infiltration speed.

Results

All the patients treated showed good results with good satisfaction of the circumferential reductions. Before treatment: Waist (cm) 78.8 ± 10.6 and hip 93.6 ± 9.0 with WHR 0.84 ± 0.07. After treatment: Waist (cm) 70.8 ± 9.6 and hip 92.6 ± 8.0 with WHR 0.76 ± 0.06. Indeed, signs of adipocyte apoptosis were observed in subcutaneous skin after injection of SAP.

Conclusion

The results showed in the present study suggest that the SAP utilized induces apoptosis of adipocytes and could be of use as a safe and effective method with which to eliminate subcutaneous abdominal fat.

Level of Evidence IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Low intakes of vitamins C and A are associated with obesity in early adulthood

To evaluate the relationships between the intake of individual antioxidants as well as the dietary antioxidant quality score and obesity-related measures. A cross-sectional study was conducted on 562 young adults. Fat mass, fat-mass percentage, and fat-free mass were measured using a body composition analyzer. The intake of antioxidant nutrients including vitamins C, E, and A, selenium, zinc, and magnesium were calculated based on a 72-hour diet recall interview. We observed significant differences in the vitamin C (88.6 ± 72.6 mg/day vs. 70.7 ± 60.6 mg/day, p = 0.010), vitamin A (635.8 ± 519.8 μg/day vs. 492.6 ± 318.9 μg/day, p = 0.014), and selenium (135.3 ± 88.7 μg/day vs. 139.3 ± 79.3 μg/day, p = 0.034) intake between normal-weight and overweight or obese young adults. When the Dietary Antioxidant Quality Score (DAQS) was analyzed, there were no significant differences between normal-weight versus overweight or obese young adults after adjusting for confounders. Logistic regression analysis revealed that vitamin C intake (odds ratio (OR) 0.995, 95% CI 0.992-0.999, p = 0.013) and vitamin A intake (OR 0.999, 95% CI 0.999-1.000, p = 0.016) were independent predictors of overweight/obesity after adjusting for age, sex and energy intake. In contrast, a higher selenium intake was associated with an increased risk of overweight/obesity (OR 1.003, 95% CI 1.000-1.006, p = 0.034). Future longitudinal investigations of dietary antioxidant intake in relation to the development of obesity would be of interest to better understand the effect of dietary antioxidants on obesity.

Glucose transporter 10 modulates adipogenesis via an ascorbic acid-mediated pathway to protect mice against diet-induced metabolic dysregulation

The development of type 2 diabetes mellitus (T2DM) depends on interactions between genetic and environmental factors, and a better understanding of gene-diet interactions in T2DM will be useful for disease prediction and prevention. Ascorbic acid has been proposed to reduce the risk of T2DM. However, the links between ascorbic acid and metabolic consequences are not fully understood. Here, we report that glucose transporter 10 (GLUT10) maintains intracellular levels of ascorbic acid to promote adipogenesis, white adipose tissue (WAT) development and protect mice from high-fat diet (HFD)-induced metabolic dysregulation. We found genetic polymorphisms in SLC2A10 locus are suggestively associated with a T2DM intermediate phenotype in non-diabetic Han Taiwanese. Additionally, mice carrying an orthologous human Glut10^G128E variant (Glut10^G128E mice) with compromised GLUT10 function have reduced adipogenesis, reduced WAT development and increased susceptibility to HFD-induced metabolic dysregulation. We further demonstrate that GLUT10 is highly expressed in preadipocytes, where it regulates intracellular ascorbic acid levels and adipogenesis. In this context, GLUT10 increases ascorbic acid-dependent DNA demethylation and the expression of key adipogenic genes, Cebpa and Pparg. Together, our data show GLUT10 regulates adipogenesis via ascorbic acid-dependent DNA demethylation to benefit proper WAT development and protect mice against HFD-induced metabolic dysregulation. Our findings suggest that SLC2A10 may be an important HFD-associated susceptibility locus for T2DM.

Environmental triggers may amplify genetically determined disease susceptibility, especially for carriers of rare variants with relatively large individual effect sizes, making these polymorphisms highly informative for predicting individualized clinical risk and preventing disease. Since transitions in dietary pattern have greatly contributed to the increased prevalence of obesity and accelerated the spread of the T2DM epidemic worldwide, a better understanding of gene-diet interactions in T2DM will be useful for disease prediction and prevention. Here, we demonstrate that polymorphisms in the gene encoding GLUT10 are associated with a T2DM intermediate phenotype in non-diabetic human subjects. Additionally, mice that carry a GLUT10 rare variant have reduced WAT development and are susceptible for HFD-induced T2DM. We further demonstrate that GLUT10 is highly expressed in preadipocytes, where it regulates intracellular ascorbic acid levels and ascorbic acid-dependent DNA demethylation to control adipogenesis. Preadipocytes carrying the GLUT10 rare variant or with knockdown of GLUT10 expression have reduced the adipogenesis. Thus, we are able to conclude that GLUT10 regulates adipogenesis via ascorbic acid-dependent DNA demethylation to affect WAT development and contribute to the sensitivity of HFD-induced metabolic dysregulation.

Dietary Approaches to Stop Hypertension (DASH): potential mechanisms of action against risk factors of the metabolic syndrome

The metabolic syndrome is a cluster of disorders dominated by abdominal obesity, hypertriacylglycerolaemia, low HDL-cholesterol, high blood pressure and high fasting glucose. Diet modification is a safe and effective way to treat the metabolic syndrome. Dietary Approaches to Stop Hypertension (DASH) is a dietary pattern rich in fruits, vegetables and low-fat dairy products, and low in meats and sweets. DASH provides good amounts of fibre, K, Ca and Mg, and limited quantities of total fat, saturated fat, cholesterol and Na. Although DASH was initially designed for the prevention or control of hypertension, using a DASH diet has other metabolic benefits. In the present review, the effect of each dietary component of DASH on the risk factors of the metabolic syndrome is discussed. Due to limited fat and high fibre and Ca content, individuals on the DASH diet are less prone to overweight and obesity and possess lower concentrations of total and LDL-cholesterol although changes in TAG and HDL-cholesterol have been less significant and available evidence in this regard is still inconclusive. Moreover, high amounts of fruit and vegetables in DASH provide great quantities of K, Mg and fibre, all of which have been shown to reduce blood pressure. K, Mg, fibre and antioxidants have also been effective in correcting glucose and insulin abnormalities. Evidence is provided from cross-sectional investigations, cohort studies and randomised controlled trials, and, where available, from published meta-analyses. Mechanisms are described according to human studies and, in the case of a lack of evidence, from animal and cell culture investigations.

Increased concentration of serum MDA, decreased antioxidants and altered trace elements and macro-minerals are linked to obesity among Bangladeshi population

BACKGROUND AND OBJECTIVE

Obesity is an emerging public health concern in Bangladesh. This study aimed to find the levels of the serum malondialdehyde (MDA), non-enzymatic antioxidants (vitamin A, C and E), trace elements (zinc and iron) and macro-minerals (calcium, potassium and sodium) in obesity and its action in disease advancement.

METHODS

Level of lipid peroxidation was estimated by measurement of the serum concentrations of malondialdehyde (MDA). Vitamin A and E concentration was found by RP-HPLC method and vitamin C was assessed for serum ascorbic acid by UV spectrophotometric method. Serum trace elements (Zn and Fe) and macro-minerals (Na, K and Ca) were estimated by Atomic Absorption Spectroscopy (AAS).

RESULTS

Our study observed significantly elevated concentrations of MDA (p < 0.001) and depleted concentrations of antioxidants (vitamin A, E and C) (p < 0.05) in the patient than control group. Analysis of serum trace elements (Zn and Fe) and macro-minerals (Na, K and Ca) and found that the mean values of Zn, Fe, Na, K and Ca were 0.39 ± 0.02 and 0.43 ± 0.03, 3284.81 ± 34.51, 162.18 ± 3.72, 44.62 ± 2.13 mg/L for the patient and 0.91 ± 0.13, 0.88 ± 0.06, 2562.74 ± 95.92, 243.58 ± 8.97, 87.66 ± 2.10 mg/L for the controls, consequently. There was a substantial difference in trace elements and macro-minerals between the patients and controls (p < 0.001).

CONCLUSION

Our study proposes that increased serum concentrations of MDA and decreased non-enzymatic antioxidant and altered trace elements and macro-minerals are powerfully related with obesity.

Vitamin C: should daily administration keep the paediatrician away?

Vitamin C is an organic compound that is almost ubiquitous in the daily diet of individuals. There are clear indications of supplementation when secondary deficiency is detected related with reduced dietary intake or reduced absorption. On the other hand, indications for supplementation concerning an increased need are controversial. Several authors have studied the role of vitamin C as an adjuvant in the treatment of diseases that may affect children and adolescents. These diseases affect all organs and systems: specifically, vitamin C supplementation could play a role in respiratory, neurological, psychiatric, oncohematological, nephrological, ophthalmological and nutritional disorders. In paediatric age, a significant benefit of vitamin C supplementation has been observed in depressive pathology, iron-deficiency anaemia and chronic renal failure related to haemodialysis. No evidence was found with vitamin C supplementation on mortality, cognitive performance, quality of life, eye diseases, infections, cardiovascular diseases and tumours. This evidence may be related to the fact that in developed countries, vitamin C is almost ubiquitous in the daily diet of each individual. In conclusion, studies on non-industrialised populations in which there could be a real benefit from such supplementation, have yet to be conducted.

Ascorbic acid inhibits visceral obesity and nonalcoholic fatty liver disease by activating peroxisome proliferator-activated receptor α in high-fat-diet-fed C57BL/6J mice

BACKGROUND/OBJECTIVES

Ascorbic acid is a known cofactor in the biosynthesis of carnitine, a molecule that has an obligatory role in fatty acid oxidation. Our previous studies have demonstrated that obesity is regulated effectively through peroxisome proliferator-activated receptor α (PPARα)-mediated fatty acid β-oxidation. Thus, this study aimed to determine whether ascorbic acid can inhibit obesity and nonalcoholic fatty liver disease (NAFLD) in part through the actions of PPARα.

DESIGN

After C57BL/6J mice received a low-fat diet (LFD, 10% kcal fat), a high-fat diet (HFD, 45% kcal fat), or the same HFD supplemented with ascorbic acid (1% w/w) (HFD-AA) for 15 weeks, variables and determinants of visceral obesity and NAFLD were examined using metabolic measurements, histology, and gene expression.

RESULTS

Compared to HFD-fed obese mice, administration of HFD-AA to obese mice reduced body weight gain, visceral adipose tissue mass, and visceral adipocyte size without affecting food consumption profiles. Concomitantly, circulating ascorbic acid concentrations were significantly higher in HFD-AA mice than in HFD mice. Ascorbic acid supplementation increased the mRNA levels of PPARα and its target enzymes involved in fatty acid β-oxidation in visceral adipose tissues. Consistent with the effects of ascorbic acid on visceral obesity, ascorbic acid not only inhibited hepatic steatosis but also increased the mRNA levels of PPARα-dependent fatty acid β-oxidation genes in livers. Similarly, hepatic inflammation, fibrosis, and apoptosis were also decreased during ascorbic acid-induced inhibition of visceral obesity. In addition, serum levels of alanine aminotransferase, aspartate aminotransferase, total cholesterol, and LDL cholesterol were lower in HFD-AA-fed mice than in those of HFD-fed mice.

CONCLUSIONS

These results suggest that ascorbic acid seems to suppress HFD-induced visceral obesity and NAFLD in part through the activation of PPARα.

Investigation of the Lipid-Lowering Effect of Vitamin C Through GSK-3β/β-Catenin Signaling in Zebrafish

Vitamin C (VC) is an essential nutrient for most fish species because of the absence of L-gulonolactone oxidase in the bodies of fish. VC plays a significant role in maintaining the physiological functions and in improving the growth performance, immunity, and survival of fish. In this study, zebrafish (Danio rerio) were treated with 8.2, 509.6, and 1007.5 mg/kg VC diets for 2 weeks, and the muscle samples were collected for gene expression analysis and biochemical index analysis. The results indicated that 509.6 and 1007.5 mg/kg VC diets inhibited glycogen synthase kinase-3β (GSK-3β) expression and induced the expression of β-catenin in the muscle of zebrafish. The mRNA expression of CCAAT/enhancer-binding protein α (C/EBPα) and fatty acid synthase (FAS), FAS activity, and the content of glycerol and triglyceride (TG) were decreased in the muscle by 509.6 and 1007.5 mg/kg VC diets. In addition, GSK-3β RNA interference was observed in zebrafish fed with 8.2 and 1007.5 mg/kg VC diets. It was found that GSK-3β RNA interference induced the mRNA expression of β-catenin but decreased the mRNA expression of C/EBPα and FAS, FAS activity, as well as the content of glycerol and TG in the muscle of zebrafish. In ZF4 cells, the mRNA expression of GSK-3β, C/EBPα, and FAS was decreased, but β-catenin expression was increased by 0.1 and 0.5 mmol/L VC treatments in vitro. The glycerol and TG content, and FAS activity in ZF4 cells were decreased by 0.1 and 0.5 mmol/L VC treatments. Moreover, the result of western blot indicated that the protein expression level of GSK-3β was significantly decreased and that of β-catenin was significantly increased in ZF4 cells treated with 0.1 and 0.5 mmol/L VC. The results from in vivo and in vitro studies corroborated that VC exerted the lipid-lowering effect through GSK-3β/β-catenin signaling in zebrafish.