Abstract
Background:
Hematological inflammatory indices are currently suggested to assess systemic inflammation. This study aims to investigate a vitamin D supplementation effect on hematological indices of inflammation in rats.
Method:
Forty-eight middle-aged male rats were allocated into a normal diet (ND) group (10% fat) and a high-fat diet (HFD) group (60% fat). The animals were fed for 26 weeks. After this period, each group was randomly divided into three subgroups, each of 8 rats: Group (1): animals were fed the ND and HFD containing 1 IU/g vitamin D for 4 months, group (2): animals were fed the ND and HFD containing 6 IU/g vitamin D for 4 months and group (3): animals were euthanized to evaluate the HFD effect. Serum 25-hydroxyvitamin D level, white blood cell count (WBCs), platelet count, platelet crit (PCT), mean platelet volume (MPV), platelet distribution width (PDW), platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR) were measured.
Results:
The HFD, significantly increased body weight, PCT, PDW, PLR, NLR, and MLR and significantly reduced serum vitamin D levels compared to the ND (P < 0.05). There was a significant decrease in food intake, MPV, PDW, and NLR after vitamin D supplementation in the ND-fed group (P < 0.05). A significant reduction in platelet count, PCT, and MLR was observed after vitamin D supplementation in HFD-fed rats (P < 0.05).
Conclusions:
In our study, some hemogram-derived inflammatory indices were higher in the HFD-fed group, and vitamin D supplementation lowering effects on some hematological indices were seen in both ND and HFD groups.
Keywords: Blood cell count, high-fat diet, inflammation, vitamin D
Introduction
The population average age is rising in developed and developing countries.[1] As the population ages, the risk of developing age-related disorders also increases.[2] So, healthy aging has become the most important global public health issue in the last few years. “Inflammaging”, low-grade, chronic, and systemic inflammation”, is one of the contributory factors in aging and age-related diseases.[3,4]
Some novel and inexpensive hematological inflammatory indicators are currently suggested to assess systemic inflammation such as neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) in different medical disorders.[5,6,7] With increasing age, NLR, and PLR values increase.[8,9] Elevated NLR, MLR, PLR, and white blood cell count (WBCs) values have been associated with unpleasant clinical-pathologic characteristics of many disorders.[9,10,11,12]
Other hemogram-derived factors involved in inflammation are platelets and platelet indices.[13,14] Mean platelet volume (MPV), platelet distribution width (PDW) and platelet crit (PCT) are platelet indices that are potential markers of platelet activation.[13,14] With aging, platelet count and platelet crit decrease, and platelet reactivity increases.[14,15] Increased platelet activity is implicated in age-related inflammatory and neurological disorders.[15]
One of the associated factors with the inflammatory status of the elderly is the quality of the diet.[16] The western dietary pattern is positively correlated with NLR.[17] High-fat diet-induced obesity increases the number of WBC, neutrophils, and lymphocytes.[18] Elevated levels of platelet counts, PCT, PLR, and WBC have been reported in obese individuals.[19]
Low vitamin D status is a common and emerging health condition in older adults.[20] According to available data, the association between vitamin D correlation and also supplementation with hematological indices is inconsistent.[21,22,23,24] More recently, a study by Stojsic Vuksanovic and colleagues found that Vitamin D3 correction in vitamin D3 deficiency and diabetes type 2/diabetic nephropathy has anti-inflammatory activity that is most pronounced on NLR and less on PLR.[25] According to an investigation by Tabatabaeizadeh and coworkers, high-dose vitamin D supplementation in adolescent girls reduces NLR.[26] Although there were several studies on the anti-inflammatory effect of vitamin D, few of them focused on hematological indices of inflammation. Therefore, in the present study, middle-aged rats were fed a normal diet (ND) and high-fat diet (HFD) and then received vitamin D supplements to be experimentally investigated concerning the HFD and vitamin D supplementation influence on WBCs, platelet count, PCT, MPV, PDW, PLR, NLR, and MLR.
Method
Experimental animals
This was an experimental intervention study. The research protocol was approved by the Ethics Committee of ?? University of Medical Sciences (??1397.472). Forty-eight healthy Wistar male rats, at 12-12.5 months, were purchased from Royan Institute. Animals were housed in animal care???. The rats were maintained at 22 ± 1°C under a 12-hour day-night cycle in a separate room.
Experimental design and procedures
After one week of acclimatization, the animals were randomized by a computer-generated randomization program into 2 groups (n = 24, each group) of ND and HFD. ND contains 70% carbohydrates, 10% fat, and 20% protein, and HFD consisted of 60% energy from fat, 20% from carbohydrates, and 20% from protein. The animals were on diets for 26 weeks. After this period, 24 rats in each group were randomly allocated into three sub-groups: Group (1): animals were fed the ND and HFD containing 1 IU/g vitamin D (Control groups; n = 8), group (2): animals were fed the ND and HFD containing 6 IU/g vitamin D (Intervention groups; n = 8) and group (3): animals were euthanized to determine the HFD effects (n = 8) [Figure 1]. The duration of the second phase was 4 months. All diets were purchased from Royan Institute for Biotechnology and met the national standard for rat feed. All animals were individually housed in cages. Food and water always were provided ad libitum during the intervention period for all rats. The animal experiments’ health was monitored daily. Their body weight was assessed at baseline and weekly during the experimental period. Daily food intake was recorded and the average intake was measured weekly throughout the study.
Figure 1.
Study method
Sample size
The sample size was determined according to the Resource Equation Method.[27]
Inclusion and exclusion criteria
Inclusion criteria were healthy male Wistar rats at 12 to 14 months of age. Lack of inclusion criteria at baseline as well as severe weight loss and morbidity during the study were exclusion criteria.
Blinding
In this study, full blinding was not possible because the researcher who conducted the experiment was not blind. However, the researcher who did the randomization, allocation of the groups, and data analysis was blind.
Outcomes
Primary outcomes were hematological indices of inflammation. Measurement of serum 25-hydroxyvitamin D 25(OH) D was a secondary outcome.
Sample collection
At the end of the study, rats were fasted overnight and received water ad libitum. Blood was collected from the heart of animals which were anesthetized by an intraperitoneal injection of xylazine hydrochloride and ketamine hydrochloride. Whole blood samples collected in EDTA tubes were used to determine the following blood indices: WBCs, platelet count, PCT, MPV, PDW, neutrophils, lymphocytes, and monocytes. All measurements were carried out using a veterinary blood cell counter. Rations were derived from complete blood count (CBC) including PLR, NLR, and MLR. The remaining blood samples were centrifuged at 1500 × g for 10 min to separate the serum for measurement of 25(OH) D. Serum 25(OH) D was assessed by High-Performance Liquid Chromatography (HPLC) method.
Statistical methods
First, the normality of the data was assessed using graphs and the Shapiro-Wilks test. Independent-Samples T-Test and Paired-Samples T-Test were used to analyze the variables with normal distribution while to analyze the non-normally distributed data Mann-Whitney U, and Wilcoxon tests were used. The experimental results were presented as means (SD) and Median (Q1-Q3). Data were analyzed by SPSS software. P value < 0.05 was regarded as a statistically significant difference.
Results
There were no significant differences in animal body weight at baseline between the ND [514.95 (13.83); n = 24] and HFD [515.66 (13.32); n = 24)] groups (P = 0.857).
Effect of a high-fat diet on body weight
The baseline body weight did not differ among the ND and HFD groups (P = 0.597). Rats maintained on the HFD showed a significantly increased body weight gain compared to the ND group after 26 weeks of feeding regimen (P = 0.007) [Table 1].
Table 1.
The effect of a high-fat diet on body weight gain in middle-aged male Wistar rats
| Variable | Groups | P | |
|---|---|---|---|
|
| |||
| ND (n=8) | HFD (n=8) | ||
| Baseline body weight (g)# | 515 (501-524.5) | 519.5 (515-520) | 0.597* |
| Final body weight (g)# | 525 (521-547.5) | 583.50 (544.25-638.25) | 0.007* |
| P** | 0.012 | 0.012 | |
| Mean difference# | 13.5 (6-27.5) | 64 (33.75-119.7) | 0.003* |
ND, normal diet; HFD, high fat diet, *Mann-Whitney U, **Wilcoxon, #Median (Q1-Q3)
Effect of a high-fat diet on food and vitamin D intake
Rats maintained on HFD consumed significantly less food and subsequently less vitamin D than the ND group (P < 0.001) [Table 2].
Table 2.
The effect of a high-fat diet on food intake, vitamin D intake, serum vitamin, D and some hematological parameters in middle-aged male Wistar rats
| Variable | Groups | P | |
|---|---|---|---|
|
| |||
| ND (n=8) | HFD (n=8) | ||
| Food intake (g/day)# | 21.37 (0.91) | 17.14 (1.03) | <0.001* |
| Vitamin D intake (IU/day)# | 21.37 (0.91) | 17.14 (1.03) | <0.001* |
| Serum 25(OH) D level (ng/ml)# | 16.65 (3.06) | 13.79 (0.56) | 0.048* |
| WBCs (103/UL)# | 3.70 (1.25) | 4.18 (1.53) | 0.497* |
| Platelet count (103/UL)## | 576 (480.50-607.00) | 612 (593.25-644.75) | 0.059** |
| PCT%# | 0.23 (0.05) | 0.29 (0.02) | 0.027* |
| MPV (fL)# | 4.46 (0.35) | 4.76 (0.17) | 0.055* |
| PDW%# | 14.25 (0.53) | 15.20 (0.20) | <0.001* |
| PLR# | 196.72 (71.63) | 359.08 (125.04) | 0.017* |
| NLR## | 0.51 (0.40-0.64) | 0.91 (0.88-1.42) | 0.003** |
| MLR## | 0.03 (0.02-0.06) | 0.11 (0.07-0.12) | 0.046** |
ND, normal diet; HFD, high fat diet; 25(OH) D, 25-hydroxy vitamin D; WBCs, white blood cells; PCT, plateletcrit; MPV, mean platelet volume; PDW, platelet distribution width; PLR, platelet-to-lymphocyte ratio; NLR, neutrophil-to-lymphocyte ratio; MLR, monocyte-to-lymphocyte ratio, *Independent-Samples T-Test, **Mann-Whitney U, #Mean (SD), ##Median (Q1-Q3)
Effect of a high-fat diet on serum vitamin D and some hematological parameters
Serum 25(OH) D level was significantly lower in the HFD group in comparison with the ND group (P = 0.048). A significant increase in PDW, PCT, PLR, NLR, and MLR was observed in rats maintained on HFD as compared to animals fed on ND (All P < 0.05). Whereas, an increase in platelet count, WBCs, and MPV in the HFD-fed rats in comparison with the ND-fed rats was not statistically significant (All P > 0.05) [Table 2].
Effects of vitamin D supplementation on body weight
Vitamin D supplementation reduced the body weight of ND and HFD-fed rats; however, this decrease was not significantly different from relevant control groups (P > 0.05). In HFD + vitamin D group, the difference between the baseline and final body weight was statistically significant (P = 0.002) [Tables 3 and 4].
Table 3.
The effect of vitamin D supplementation on body weight, food intake, and vitamin D intake in normal diet fed rats
| Variable | Groups | P | |
|---|---|---|---|
|
| |||
| Control (n=8) | Vitamin D (n=8) | ||
| Baseline body weight (g)# | 531.75 (31.44) | 531.25 (16/33) | 0.969* |
| Final body weight (g)# | 527.87 (54.56) | 512.12 (29.74) | 0.485* |
| P** | 0.729 | 0.069 | |
| Baseline Food intake (g/day)## | 21.10 (20.42-21.32) | 20.77 (20.01-21.89) | 0.834*** |
| Final Food intake (g/day)## | 20. 26 (19.87-21.03) | 19.14 (17.89-19.81) | 0.005*** |
| P**** | 0.012 | 0.012 | |
| Baseline Vitamin D intake (IU/day)## | 21.10 (20.42-21.32) | 20.77 (20.01-21.89) | 0.834*** |
| Final Vitamin D intake (IU/day) # | 20.52 (0.87) | 113.19 (6.70) | 0.001* |
*Independent-Samples T-Test, **Paired-Samples T Test, ***Mann-Whitney U, ****Wilcoxon, #Mean (SD), ##Median (Q1-Q3)
Table 4.
The effect of vitamin D supplementation on body weight, food intake, and vitamin D intake in high-fat diet fed rats
| Variable | Groups | P | |
|---|---|---|---|
|
| |||
| Control (n=8) | Vitamin D (n=8) | ||
| Baseline body weight (g)# | 592.12 (42.10) | 591.5 (49.52) | 0.979* |
| Final body weight (g)# | 588.25 (37.61) | 550.62 (38.12) | 0.067* |
| P** | 0.183 | 0.002 | |
| Baseline Food intake (g/day)# | 16.91 (1.05) | 16.73 (1.10) | 0.754* |
| Final Food intake (g/day)## | 15.71 (15.13-16.60) | 14.68 (13.99-14.74) | 0.005*** |
| P**** | 0.093 | 0.012 | |
| Baseline Vitamin D intake (IU/day)# | 16.91 (1.05) | 16.73 (1.1) | 0.754* |
| Final Vitamin D intake (IU/day)## | 15.71 (15.13-16.60) | 88.11 (83.95-88.46) | 0.001*** |
*Independent-Samples T-Test, **Paired-Samples T Test, ***Mann-Whitney U, ****Wilcoxon, #Mean (SD), ##Median (Q1-Q3)
Effects of vitamin D supplementation on Food and vitamin D intake
Vitamin D supplementation significantly decreased the food consumption of the intervention group versus the control group (P < 0.05). The average daily vitamin D intake was significantly increased in both vitamin D-treated groups (P < 0.05) [Tables 3 and 4].
Effects of vitamin D supplementation on serum vitamin D and some hematological parameters
As expected, Vitamin D supplementation gives rise to higher serum 25 (OH) D levels in both vitamin D-treated groups. Vitamin D supplements in ND + vitamin D group significantly decreased the MPV, PDW, and NLR compared with the relevant control group (All P < 0.05). However, after vitamin D supplementation, a non-significant increase in platelet count, PCT, and WBC and an insignificant decrease in PLR and MLR values were observed in ND + vitamin D group versus the relevant control group (All P > 0.05). Vitamin D supplementation significantly reduced platelet count, PCT, and MLR in the HFD + vitamin D group (All P < 0.05). In HFD + vitamin D group versus the HFD group the observed decrease in MPV, PLR, and NLR was not statistically significant (All P > 0.05) [Tables 5 and 6].
Table 5.
The effect of vitamin D supplementation on serum vitamin D and some hematological parameters in normal diet fed rats
| Variable | Groups | P | |
|---|---|---|---|
|
| |||
| Control (n=8) | Vitamin D (n=8) | ||
| Serum 25(OH) D level (ng/ml)# | 11.86 (1.13) | 27.78 (1.30) | <0.001* |
| WBCs (103/UL)# | 3.63 (0.62) | 4.05 (0.79) | 0.268* |
| Platelet count (103/UL)# | 522.25 (55.40) | 630.62 (139.17) | 0.060* |
| PCT %# | 0.24 (0.03) | 0.27 (0.08) | 0.350* |
| MPV (fL)# | 4.75 (0.24) | 4.37 (0.42) | 0.048* |
| PDW %# | 15.12 (0.38) | 14.47 (0.27) | 0.002* |
| PLR## | 233.14 (206.44-286.35) | 228.12 (221.79-239.28) | 0.908** |
| NLR# | 0.63 (0.05) | 0.55 (0.07) | 0.029* |
| MLR# | 0.02 (0.02) | 0.01 (0.01) | 0.378* |
25(OH) D, 25-hydroxy vitamin D; WBCs, white blood cells; PCT, plateletcrit; MPV, mean platelet volume; PDW, platelet distribution width; PLR, platelet-to-lymphocyte ratio; NLR, neutrophil-to-lymphocyte ratio; MLR, monocyte-to lymphocyte ratio, *Independent- Samples T-Test, **Mann-Whitney U, #Mean (SD), ##Median (Q1-Q3)
Table 6.
The effect of vitamin D supplementation on serum vitamin D and some hematological parameters in high-fat diet fed rats
| Variable | Groups | P | |
|---|---|---|---|
|
| |||
| Control (n=8) | Vitamin D (n=8) | ||
| Serum 25(OH) D level (ng/ml)# | 10.30 (10.00-11.22) | 23.05 (22.55-23.12) | 0.002* |
| WBCs (103/UL)## | 3.87 (1.59) | 3.58 (1.4) | 0.708** |
| Platelet count (103/UL)## | 612.87 (31.89) | 533.87 (35.14) | <0.001** |
| PCT %## | 0.28 (0.03) | 0.23 (0.02) | 0.006** |
| MPV (fL)## | 4.62 (0.51) | 4.46 (0.33) | 0.468** |
| PDW %## | 14.60 (0.47) | 14.63 (0.46) | 0.875** |
| PLR## | 314.71 (100.22) | 263.44 (72.10) | 0.333** |
| NLR## | 1.02 (0.19) | 0.80 (0.24) | 0.117** |
| MLR## | 0.04 (0.006) | 0.02 (0.01) | 0.005** |
25(OH) D, 25-hydroxy vitamin D; WBCs, white blood cells; PCT, plateletcrit; MPV, mean platelet volume; PDW, platelet distribution width; PLR, platelet-to-lymphocyte ratio; NLR, neutrophil-to-lymphocyte ratio; MLR, monocyte-to lymphocyte ratio, *Mann-Whitney U, **Independent-Samples T-Test, #Median (Q1-Q3), ##Mean (SD)
Discussion
In the present study, the HFD harmful effect and some protective impact of vitamin D supplementation on some CBC-derived inflammatory indices in aging rats were shown. Considering that the animals were middle-aged at the baseline, and middle age is a high-risk period for weight gain[28] in our study, body weight gradually increased as they got older, regardless of the diet type, but the rats maintained on the HFD showed significantly more body weight than ND-fed rats.
In the current research, vitamin D supplementation in elderly rats resulted in non-significant weight loss in both vitamin D treated groups compared to control groups. Our results are in line with earlier literature that found vitamin D administration had a significant influence on increased serum 25(OH) D levels[29] and also reduced food intake in animals maintained on both ND and HFD.[30] This finding also supports Park's study which concluded that serum 25(OH) D level has a dose-response correlation with dietary vitamin D intake.[31]
Our data revealed that high-fat diet consumption in middle age can affect platelet parameters. The observed increase in PCT and PDW was significant. ÇEÇEN found that there is a significant association between PLT activation (PLT and PCT increase) and body fat amount[32] which is in agreement with the results of this study. In the ND group, vitamin D supplementation significantly decreased some platelet indices such as PDW and MPV.
We found that HFD consumption elevates the PLR value, and vitamin D in the elderly experiments alleviated this inflammatory biomarker level; however, this decrease was not statistically significant. In line with our findings, Vuksanovic and colleagues showed that vitamin D3 correction has less effect on PLR.[25] Assuming that a higher PLR value has been recommended as a risk factor for age-related disorders such as sarcopenia,[7] eating a healthy diet, and correcting and preventing micronutrient deficiencies such as vitamin D can help healthy aging.
The NLR and MLR values increased in animals from the HFD group. These enhancements suggest that inflammation may be augmented in HFD-fed middle-aged rats. Consistent with the findings of Tabatabaeizadeh[26] our findings showed that vitamin D can have a lowering impact on NLR as an inflammatory factor. This improving the effect of vitamin D supplementation was significant in the ND group while in HFD-fed rats, it was not statistically significant. The reason for the intervention's different effect is probably low vitamin D intake and accordingly lower 25(OH) D levels in the HFD group owing to low food consumption. Our result is in line with earlier literature that found improvement in lifestyle behaviors (diet and physical activity) can significantly lower NLR values.[33]
Considering that in the elderly, elevated NLR value is correlated with an increased risk of cognitive impairment[34] vitamin D supplementation in older adults might help slow down age-related health problems by reducing NLR values. In this study, a significant decline in platelet count, PCT, and MLR was observed following the vitamin D supplementation of the HFD-feed rats. This shows that vitamin D supplementation ameliorates inflammations caused by HFD in older animals.
The inverse association of vitamin D and inflammatory markers reported in previous studies,[35,36] in agreement with our results, suggests anti-inflammatory impacts of vitamin D on some CBC-derived inflammatory indices in aging rats. The results of the second phase are consistent with the findings of previous studies by Al-Nimer, which showed that vitamin D3 supplement as an add-on-therapy with iron sulfate in participants with iron deficiency anemia significantly increased the WBCs and decreased significantly the platelet count, PCT, MPV.[22]
We were unable to detect a significant reducing impact of vitamin D supplementation on MLR in ND-fed rats and MPV values in the HFD group. Some studies have reported beneficial and lowering effects and another report suggests the in-effectivity of vitamin D in the modulation of obesity-related inflammation; however, in the present study, we observed the ameliorating effects of vitamin D on some HFD-related hematological systemic inflammatory factors. Additionally, a high-fat diet consumption in middle age might alter the CBC parameters, and some of these alterations can be modified by vitamin D supplementation. However, further studies are needed to support this beneficial effect on elderly people in a clinical trial.
Conclusions
Vitamin D could ameliorate HFD-related side effects and also age-related problems. The main findings can be summarized as follows: 1. A HFD consumption significantly increases PCT, PDW, PLR, NLR, and MLR values. 2. Platelet count, PCT, and MLR values decrease significantly after vitamin D supplementation in HFD-fed rats. 3. Vitamin D supplementation reduces the MPV, PDW, and NLR in ND-fed rats.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
- 1.Ageing and health: World Health Organization. Available from: https://www.who.int/news-room/fact-sheets/detail/ageingand-health.
- 2.Wang Y, Zhang R, Shen Y, Su L, Dong B, Hao Q. Prediction of chemotherapy adverse reactions and mortality in older patients with primary lung cancer through frailty index based on routine laboratory data. Clin Interv Aging. 2019;14:1187–97. doi: 10.2147/CIA.S201873. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Farokhimanesh S, Komeili A. Nutraceuticals with pleiotropic anti-inflammatory functions for mitigating meta-inflammation. Food Health J. 2019;2:16–8. [Google Scholar]
- 4.Franceschi C, Campisi J. Chronic inflammation (inflammaging) and its potential contribution to age-associated diseases. J Gerontol A Biol Sci Med Sci. 2014;69(Suppl 1):S4–9. doi: 10.1093/gerona/glu057. [DOI] [PubMed] [Google Scholar]
- 5.Yombi JC, Schwab P-E, Thienpont E. Neutrophil-to-lymphocyte ratio (NLR) distribution shows a better kinetic pattern than C-reactive protein distribution for the follow-up of early inflammation after total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc. 2016;24:3287–92. doi: 10.1007/s00167-015-3921-0. [DOI] [PubMed] [Google Scholar]
- 6.Zuo B, Zhu S, Meng X, Zhao D, Zhang J. Monocyte/lymphocyte ratio is associated with carotid stenosis in ischemic stroke: A retrospective analysis. Brain Behav. 2019;9:e01429. doi: 10.1002/brb3.1429. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Liaw F-Y, Huang C-F, Chen W-L, Wu L-W, Peng T-C, Chang Y-W, et al. Higher platelet-to-lymphocyte ratio increased the risk of sarcopenia in the community-dwelling older adults? Sci Rep. 2017;7:1–8. doi: 10.1038/s41598-017-16924-y. doi: 10.1038/s41598.017.16924.y. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Akbas EM, Gungor A, Ozcicek A, Akbas N, Askin S, Polat M. Vitamin D and inflammation: Evaluation with neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio. Arch Med Sci. 2016;12:721–7. doi: 10.5114/aoms.2015.50625. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Li L, Ma Y, Geng Xb, Tan Z, Wang Jh, Cui C, et al. Platelet-to-lymphocyte ratio relates to poor prognosis in elderly patients with acute myocardial infarction. Aging Clin Exp Res. 2021;33:619–24. doi: 10.1007/s40520-020-01555-7. [DOI] [PubMed] [Google Scholar]
- 10.Gijsberts CM, Ellenbroek GH, Maarten J, Huisman A, van Solinge WW, Lam CS, et al. Effect of monocyte-to-lymphocyte ratio on heart failure characteristics and hospitalizations in a coronary angiography cohort. Am J Cardiol. 2017;120:911–6. doi: 10.1016/j.amjcard.2017.06.020. [DOI] [PubMed] [Google Scholar]
- 11.Akbas EM, Demirtas L, Ozcicek A, Timuroglu A, Bakirci EM, Hamur H, et al. Association of epicardial adipose tissue, neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio with diabetic nephropathy. Int J Clin Exp Med. 2014;7:1794–801. [PMC free article] [PubMed] [Google Scholar]
- 12.Vozarova B, Weyer C, Lindsay RS, Pratley RE, Bogardus C, Tataranni PA. High white blood cell count is associated with a worsening of insulin sensitivity and predicts the development of type 2 diabetes. Diabetes. 2002;51:455–61. doi: 10.2337/diabetes.51.2.455. [DOI] [PubMed] [Google Scholar]
- 13.Budak YU, Polat M, Huysal K. The use of platelet indices, plateletcrit, mean platelet volume and platelet distribution width in emergency non-traumatic abdominal surgery: A systematic review. Biochem Med (Zagreb) 2016;26:178–93. doi: 10.11613/BM.2016.020. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Santimone I, Di Castelnuovo A, De Curtis A, Spinelli M, Cugino D, Gianfagna F, et al. White blood cell count, sex and age are major determinants of heterogeneity of platelet indices in an adult general population: Results from the MOLI-SANI project. Haematologica. 2011;96:1180–8. doi: 10.3324/haematol.2011.043042. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15.Montenont E, Rondina MT, Campbell RA. Altered functions of platelets during aging. Curr Opin Hematol. 2019;26:336–42. doi: 10.1097/MOH.0000000000000526. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Rodríguez-Rodríguez E, López-Sobaler AM, Ortega RM, Delgado-Losada ML, López-Parra AM, Aparicio A. Association between neutrophil-to-lymphocyte ratio with abdominal obesity and healthy eating index in a representative older Spanish population? Nutrients. 2020;12:855. doi: 10.3390/nu12030855. doi: 10.3390/nu12030855. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Syauqy A, Hsu C-Y, Rau H-H, Chao JC. Association of dietary patterns, anthropometric measurements, and metabolic parameters with C-reactive protein and neutrophil-to-lymphocyte ratio in middle-aged and older adults with metabolic syndrome in Taiwan: A cross-sectional study. Nutr J. 2018;17:106. doi: 10.1186/s12937-018-0417-z. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Maysami S, Haley MJ, Gorenkova N, Krishnan S, McColl BW, Lawrence CB. Prolonged diet-induced obesity in mice modifies the inflammatory response and leads to worse outcome after stroke. J Neuroinflammation. 2015;12:140. doi: 10.1186/s12974-015-0359-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.Erdal E, İnanir M. Platelet-to-lymphocyte ratio (PLR) and Plateletcrit (PCT) in young patients with morbid obesity. Rev Assoc Med Bras. 2019;65:1182–7. doi: 10.1590/1806-9282.65.9.1182. [DOI] [PubMed] [Google Scholar]
- 20.Song H-R, Kweon S-S, Choi J-S, Rhee J, Lee Y-H, Nam H-S, et al. High prevalence of vitamin D deficiency in adults aged 50 years and older in Gwangju, Korea: The Dong-gu study. J Korean Med Sci. 2014;29:149–52. doi: 10.3346/jkms.2014.29.1.149. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Yilmaz M, Gedik A, Demir T, Eraydin A, Cimrin D, Comlekci A, et al. Is there a relationship between neutrophil/lymphocyte ratio and vitamin D levels in individuals over 65 years of age? 17th European Congress of Endocrinology; 2015: BioScientifica [Google Scholar]
- 22.Al-Nimer MS, HamaSalih RM. Effects of Vitamin D3 supplementation on the hematological indices in women presented with iron deficiency anemia: An open-labeled clinical trial. J Pharm Negative Results. 2019;10 doi: 10.4103/jpnr.JPNR_7_19. [Google Scholar]
- 23.Soliman AT, Eldabbagh M, Elawwa A, Ashour R, Saleem W. The effect of vitamin D therapy on hematological indices in children with vitamin D deficiency. J Trop Pediatr. 2012;58:523–4. doi: 10.1093/tropej/fms020. [DOI] [PubMed] [Google Scholar]
- 24.Soliman AT, Eldabbagh M, Elawwa A, Saleem W. Does vitamin D therapy affect hematological indices in adolescents with vitamin D deficiency? ndian J Endocrinol Metab. 2012;16:659–60. doi: 10.4103/2230-8210.98038. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 25.Tatjana Stojsic Vuksanovic VK. Impact of vitamin D3 correction on new chronic inflammation markers: Neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratioin patient with vitamin D3 deficiency and diabetes type 2/diabetic nephropathy. Int J Adv Res. 2020;8:938–51. [Google Scholar]
- 26.Tabatabaeizadeh SA, Avan A, Bahrami A, Khodashenas E, Esmaeili H, Ferns GA, et al. High dose supplementation of vitamin D affects measures of systemic inflammation: Reductions in high sensitivity C-reactive protein level and neutrophil to lymphocyte ratio (NLR) distribution. J Cell Biochem. 2017;118:4317–22. doi: 10.1002/jcb.26084. [DOI] [PubMed] [Google Scholar]
- 27.Festing MF. Design and statistical methods in studies using animal models of development. ILAR J. 2006;47:5–14. doi: 10.1093/ilar.47.1.5. [DOI] [PubMed] [Google Scholar]
- 28.Barendregt FW, Mackenbach J, Mamun A. Overweight and Obesity by Middle Age Are Associated with Shortened Lifespan [Google Scholar]
- 29.Hemamy M, Heidari-Beni M, Askari G, Karahmadi M, Maracy M. Effect of Vitamin D and magnesium supplementation on behavior problems in children with attention-deficit hyperactivity disorder? Int J Prev Med. 2020;11:4. doi: 10.4103/ijpvm.IJPVM_546_17. doi: 10.4103/ijpvm.IJPVM_546_17. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 30.Farhangi MA, Mesgari-Abbasi M, Nameni G, Hajiluian G, Shahabi P. The effects of vitamin D administration on brain inflammatory markers in high fat diet induced obese rats? BMC Neurosci. 2017;18:1–8. doi: 10.1186/s12868-017-0400-1. doi: 10.1186/s12868.017.0400.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 31.Park CY, Shin Y, Kim J-H, Zhu S, Jung YS, Han SN, et al. Effects of high fat diet-induced obesity on vitamin D metabolism and tissue distribution in vitamin D deficient or supplemented mice? Nutr Metab (Lond) 2020;17:1–12. doi: 10.1186/s12986-020-00463-x. doi: 10.1186/s12986.020.00463.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 32.ÇEÇEN S. Platelet activation is a risk factor for obesity. Turkish J Endocrinol Metab. 2020;24:132–7. [Google Scholar]
- 33.Wang R, Chen PJ, Chen WH. Diet and exercise improve neutrophil to lymphocyte ratio in overweight adolescents. Int J Sports Med. 2011;32:e1–5. doi: 10.1055/s-0031-1283185. [DOI] [PubMed] [Google Scholar]
- 34.Liu J-H, Zhang Y-J, Ma Q-H, Sun H-P, Xu Y, Pan C-W, et al. Elevated blood neutrophil to lymphocyte ratio in older adults with cognitive impairment? Arch Gerontol Geriatr. 2020;88:104041. doi: 10.1016/j.archger.2020.104041. doi: 10.1016/j.archger.2020.104041. [DOI] [PubMed] [Google Scholar]
- 35.Wang Q, Zhu Z, Liu Y, Tu X, He J. Relationship between serum vitamin D levels and inflammatory markers in acute stroke patients? Brain Behav. 2018;8:e00885. doi: 10.1002/brb3.885. doi: 10.1002/brb3.885. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 36.Ganji V, Tangpricha V, Zhang X. Serum vitamin D concentration ≥75 nmol/L is related to decreased cardiometabolic and inflammatory biomarkers, metabolic syndrome, and diabetes; and increased cardiorespiratory fitness in US adults? Nutrients. 2020;12:730. doi: 10.3390/nu12030730. doi: 10.3390/nu12030730. [DOI] [PMC free article] [PubMed] [Google Scholar]