The Interplay of Vitamin D Deficiency and Cellular Senescence in The Pathogenesis of Obesity-Related Co-Morbidities

The interplay between vitamin D status, subclinical inflammation, and prediabetes

Vitamin D's role extends beyond classical calcium and phosphate homeostasis to encompass a pivotal influence on immune modulation and metabolic health. The mechanisms by which vitamin D exerts these effects involve its conversion to hormonally active calcitriol, which binds intracellular vitamin D receptors, initiating various downstream cascades. In this review, we tease out the evidence showing the relationship between vitamin D deficiency and prediabetes within the context of subclinical inflammation, with a special focus on the novel monocyte-to-HDL ratio (MHR), a novel inflammatory marker reflecting subclinical inflammation. This was based on a thorough literature review using reputable databases covering the period from 1980 to 2024. In light of this, we discuss calcitriol's anti-inflammatory effects and consequently link vitamin D deficiency to both overt and subclinical inflammation. Additionally, the utility of several biomarkers, notably MHR, in investigating this association is also discussed. We further reviewed the role of vitamin D deficiency in precipitating prediabetes and type 2 diabetes mellitus (T2DM) via insulin resistance, decreased insulin synthesis and secretion, and subclinical inflammation. Taken together, this mini review highlights that vitamin D deficiency is significantly associated with subclinical inflammation, playing a critical role in the development of prediabetes and the progression to T2DM. Addressing vitamin D deficiency through appropriate interventions may serve as a preventative measure against the development of prediabetes and T2DM.

Confronting the global obesity epidemic: investigating the role and underlying mechanisms of vitamin D in metabolic syndrome management

The escalating prevalence of MetS, driven by global obesity trends, underscores the urgent need for innovative therapeutic strategies. To gain a deeper understanding of the therapeutic potential of vitamin D in addressing MetS, we embarked on a targeted literature review that thoroughly examines the scientific underpinnings and pivotal discoveries derived from pertinent studies, aiming to unravel the intricate mechanisms through which vitamin D exerts its effects on MetS and its components. This article explores the multifunctional role of vitamin D in the management of MetS, focusing on its regulatory effects on insulin sensitivity, lipid metabolism, inflammation, and immune response. Through an extensive review of current research, we unveil the complex mechanisms by which vitamin D influences MetS components, highlighting its potential as a therapeutic agent. Our analysis reveals that vitamin D's efficacy extends beyond bone health to include significant impacts on cellular and molecular pathways critical to MetS. We advocate for further research to optimize vitamin D supplementation as a component of precision medicine for MetS, considering the safety concerns related to dosage and long-term use.

Association between Serum Vitamin D Status and Circadian Syndrome: A Cross-Sectional Study

BACKGROUND

Circadian Syndrome (CircS) encompasses cardiometabolic risk factors and comorbidities, indicating an elevated susceptibility to cardiovascular disease and type 2 diabetes.

METHODS

This cross-sectional study aimed to investigate the association between vitamin D levels and each of the following: CircS, metabolic syndrome (MetS), and the individual components of CircS. Data from 14,907 adults who participated in the National Health and Nutrition Examination Survey (NHANES) between 2007 and 2018 were utilized. CircS was defined based on MetS components, alongside depression, short sleep, and non-alcoholic fatty liver disease (NAFLD).

RESULTS

Our results indicated that low vitamin D levels exhibited meaningful associations with CircS, with vitamin D deficiency and inadequacy demonstrating 2.21-fold (95% CI 1.78-2.74, p < 0.001) and 1.33-fold (95% CI 1.14-1.54, p < 0.001) increases in CircS odds, respectively. The association between vitamin D deficiency and CircS was stronger than that with MetS. Additionally, a dose-response gradient in odds of CircS components, particularly with short sleep duration, was noted as serum vitamin D levels decreased.

CONCLUSIONS

our findings highlight a significant association between low serum vitamin D levels and CircS and its components, particularly with short sleep. This suggests a potentially pivotal role of vitamin D in the pathogenesis of Circadian syndrome.

Serum Vitamin D Level in Overweight Individuals and Its Correlation With the Incidence of Non-alcoholic Fatty Liver Disease

In this study, we investigated the serum vitamin D level in overweight individuals and its correlation with the incidence of nonalcoholic fatty liver disease (NAFLD). Between May 2020 and May 2021, the Department of Gastroenterology at the People's Hospital of Henan University of Traditional Chinese Medicine treated a total of 321 outpatients and inpatients with NAFLD, who were included in the NAFLD group, while 245 healthy age- and gender-matched individuals were included in the control group. All the data were collected for the relevant indices, including fasting plasma glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, alanine transaminase, and 25-hydroxy vitamin D (25[OH]D. The patients with NAFLD were divided into the normal BMI group, the overweight group, and the obese group, according to the body mass index, and the 25(OH)D levels were compared between the different groups. Spearman's correlation analysis was performed to analyze the correlation between the serum 25(OH)D level and NAFLD. Regarding the serum 25 (OH)D level, it was lower in the NAFLD group than in the control group ([18.36 + 1.41] µg/L vs [22.33 + 2.59] µg/L, t = ?5.15, P<0.001), and was lower in the overweight group than in the normal group ([18.09 ± 5.81] µg/L vs [20.60 ± 4.16] µg/L, t = 0.26, P = 0.041). The serum 25(OH)D level was thus negatively correlated with the incidence of NAFLD in overweight individuals (r = 0.625, P<0.05). In conclusion, the level of 25(OH)D decreased in patients with NAFLD with increasing BMI (normal, overweight, obese). Keywords: Nonalcoholic fatty liver disease, Vitamin D.

Obesity and malnutrition in children and adults: A clinical review

Background

In the U.S., children and adults are consuming more low-nutrient foods with added sugar and excess fats as compared to healthy, high-quality calories and micronutrients. This diet is increasing the prevalence of malnutrition and nutritional deficiencies, despite high calorie intake. This is a review of the common micronutrient deficiencies, the risk factors for malnutrition, dietary plans, and the health consequences in children and adults with obesity in the U.S.

Methods

This clinical review of literature was performed on the MEDLINE (PubMed) search engine. A total of 1391 articles were identified and after review, a total of 130 were found to be most pertinent.

Discussion

The most common micronutrient deficiencies found in patients with obesity were vitamin A, thiamine (B1), folate (B9), cobalamin (B12), vitamin D, iron, calcium, and magnesium, especially prior and after bariatric surgery. Diets that produced the most weight reduction also further puts these individuals at risk for worsening malnutrition. Malnutrition and micronutrient deficiencies can worsen health outcomes if not properly managed.

Conclusion

Adequate screening and awareness of malnutrition can improve the health outcomes in patients with obesity. Physiologic changes in response to increased adiposity and inadequate intake increase this population's risk of adverse health effects. Malnutrition affects the individual and contributes to worse public health outcomes. The recommendations for screening for malnutrition are not exclusive to individuals undergoing bariatric procedures and can improve the health outcomes of any patient with obesity. However, clearly, improved nutritional status can assist with metabolism and prevent adverse nutritional outcomes post-bariatric surgery. Clinicians should advise on proper nutrition and be aware of diets that worsen deficiencies.

Vitamin D Deficiency and Its Association With Cardiovascular Diseases Among Patients Attending a Private Tertiary Sector Cardiovascular Heart Clinic in Nairobi

BACKGROUND

Vitamin D deficiency is a common condition that affects approximately 30-50% of the worldwide population. Vitamin D deficiency is associated with an increased risk of cardiometabolic diseases and is considered a cardiovascular risk factor globally.  Methods: This is a retrospective cross-sectional study that aimed to identify the prevalence of vitamin D deficiency and its associations with the cardiovascular disease (CVD) risk profile of patients presenting for cardiac evaluation at Primecare Heart Clinic, a private heart clinic in Nairobi, Kenya, between January 1, 2020 and January 31, 2022.

RESULTS

Females with vitamin D deficiency composed 58.87% of the study participants. The average 10-year Framingham CVD risk level of the vitamin D-deficient participants was 7.09%. Participants with vitamin D deficiency that were older and had low serum high-density lipoprotein C (HDL-C) levels and high systolic blood pressure (BP) had a higher risk of CVDs. Male participants were at five times higher risk of CVDs. Vitamin D-deficient patients who were older and had a low HDL cholesterol level and high systolic BP are at a high risk of CVDs. The two-way analysis of variance (ANOVA) test value was 345.6992, and the p-value was 0.002884.

CONCLUSION

Our study demonstrated that a low level of vitamin D was associated with a higher Framingham cardiovascular risk score and cardiovascular risk in patients. Nonetheless, this is a retrospective study, which is a major limitation of this study.

Association of Vitamin D Status With Metabolic Syndrome and Its Individual Risk Factors: A Cross-Sectional Study

Background Vitamin D deficiency has been associated with metabolic syndrome and its related outcomes, including type 2 diabetes mellitus, cardiovascular disease, myocardial infarction, and stroke. However, studies in Indian populations have provided conflicting results. Methods This single-center cross-sectional study was conducted in a tertiary care hospital in north India to determine the prevalence of vitamin D deficiency in patients with metabolic syndrome and to study the correlations of individual components of metabolic syndrome with 25 hydroxy vitamin D levels. The study included 235 patients aged between 30 to 70 years who met the criteria for metabolic syndrome. Patients with diabetes, hypothyroidism, Cushing's, and other disorders affecting vitamin D status, on supplements of vitamin D or anti-dyslipidaemic drugs were excluded. Information regarding socio-demographic characteristics, medical history, and anthropometric measurements were collected. Blood samples were collected to assess vitamin D levels. Results The prevalence of vitamin D deficiency (<20 ng/ml) was 76% among the study population. There was a significant negative correlation between vitamin D levels and diastolic blood pressure (Spearman's rho: -0.134, 95% CI: -0.82,-0.260, p=0.040), fasting blood glucose (Spearman's rho: -0.142, 95% CI: -0.101,-0.269, p=0.029), A weak correlation was also found between vitamin D3 levels and total cholesterol (Spearman's rho: -0.246, 95% CI: -0.119,-0.367, p<0.001), triglyceride levels (Spearman's rho: -0.246, 95% CI: -0.118,-0.370, p<0.001) and low-density lipoprotein (LDL) levels (Spearman's rho: -0.229, 95% CI: -0.102,-0.351, p<0.001). Conclusion The study findings suggest that vitamin D deficiency is prevalent among patients with metabolic syndrome in north India. There is a significant negative correlation between vitamin D levels and some components of metabolic syndrome. This highlights the need for further research to understand the underlying mechanisms and potential benefits of vitamin D supplementation in this population. Identification of high-risk individuals for hypovitaminosis D can aid in streamlining treatment guidelines and preventing unnecessary prescription of investigations in developing countries.

Eldecalcitol prevented OVX-induced osteoporosis through inhibiting BMSCs senescence by regulating the SIRT1-Nrf2 signal

Background: Aging and oxidative stress are considered to be the proximal culprits of postmenopausal osteoporosis. Eldecalcitol (ED-71), a new active vitamin D derivative, has shown a good therapeutic effect on different types of osteoporosis, but the mechanism is unclear. This study focused on exploring whether ED-71 could prevent bone loss in postmenopausal osteoporosis by regulating the cell senescence of bone mesenchymal stem cells (BMSCs), and explaining its specific mechanism of action. Materials and methods: An ovariectomized (OVX) rat model was established and 30 ng/kg ED-71 was administered orally once a day. The weight of rats was recorded regularly. Micro-computed tomography (CT) and histochemical staining were used to evaluate bone mass, histological parameters, and aging-related factors. Rat bone mesenchymal stem cells were extracted and cultivated in vitro. Aging cells were marked with senescence-associated β-gal (SA-β-gal) dyeing. The mRNA and protein levels of aging-related factors and SIRT1-Nrf2 signal were detected by RT-PCR, Western blot, and immunofluorescence staining. The reactive oxygen species (ROS) levels were detected by DCFH-DA staining. Results: Compared with the Sham group, the bone volume of the ovariectomized group rats decreased while their weight increased significantly. ED-71 prevented bone loss and inhibited weight gain in ovariectomized rats. More importantly, although the expression of aging-related factors in the bone tissue increased in the ovariectomized group, the addition of ED-71 reversed changes in these factors. After extracting and in vitro culturing bone mesenchymal stem cells, the proportion of aging bone mesenchymal stem cells was higher in the ovariectomized group than in the Sham group, accompanied by a significant decrease in the osteogenic capacity. ED-71 significantly improved the bone mesenchymal stem cells senescence caused by ovariectomized. In addition, ED-71 increased the expression of SIRT1 and Nrf2 in ovariectomized rat bone mesenchymal stem cells. Inhibition of SIRT1 or Nrf2 decreased the inhibitory effect of ED-71 on bone mesenchymal stem cells senescence. ED-71 also showed a suppression effect on the reactive oxygen species level in bone mesenchymal stem cells. Conclusion: Our results demonstrated that ED-71 could inhibit the cell senescence of bone mesenchymal stem cells in ovariectomized rats by regulating the SIRT1-Nrf2 signal, thereby preventing bone loss caused by osteoporosis.

Nutritional components as mitigators of cellular senescence in organismal aging: a comprehensive review

The process of cellular senescence is rapidly emerging as a modulator of organismal aging and disease. Targeting the development and removal of senescent cells is considered a viable approach to achieving improved organismal healthspan and lifespan. Nutrition and health are intimately linked and an appropriate dietary regimen can greatly impact organismal response to stress and diseases including during aging. With a renewed focus on cellular senescence, emerging studies demonstrate that both primary and secondary nutritional elements such as carbohydrates, proteins, fatty acids, vitamins, minerals, polyphenols, and probiotics can influence multiple aspects of cellular senescence. The present review describes the recent molecular aspects of cellular senescence-mediated understanding of aging and then studies available evidence of the cellular senescence modulatory attributes of major and minor dietary elements. Underlying pathways and future research directions are deliberated to promote a nutrition-centric approach for targeting cellular senescence and thus improving human health and longevity.