The Effects of Vitamin D Supplementation on Anthropometric and Biochemical Indices in Patients With Non-alcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

Co-administration of probiotic and vitamin D significantly improves cognitive function in schizophrenic patients: A double-blinded randomized controlled trial

AIM

Manipulation of the intestinal microbiome and supplying vitamin D can attenuate psychiatric symptoms in schizophrenic patients. The current study tried to evaluate the effects of probiotic/vitamin D supplementation on the cognitive function and disease severity of schizophrenic patients.

METHODS

In the present study, 70 patients (aged 18-65) with schizophrenia were recruited. Participants were randomly allocated to the placebo (n = 35) and intervention (probiotic supplements+400 IU vitamin D, n = 35) groups. Severity of disease and cognitive function (primary outcomes) were evaluated by Positive and Negative Syndrome Scale (PANSS) and Montreal Cognitive Assessment (MoCA) tests, respectively. Moreover, lipid profile, body mass index (BMI), gastrointestinal (GI) problems, serum C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were evaluated as secondary outcomes.

RESULTS

A total of 69 patients completed the study. The MoCA score was increased by 1.96 units in the probiotic-containing supplement group compared to the placebo (p = 0.004). Also, the percentage of subjects with MoCA score ≥ 26 rose significantly in the intervention group (p = 0.031). Moreover, TC (p = 0.011), FBS (p = 0.009), and CRP (p < 0.001) significantly decreased in the supplement group compared to the placebo. Although the probiotic supplement reduced PANSS score by 2.82 units, the difference between the study groups was not statistically significant (p = 0.247).

CONCLUSION

Co-administration of probiotics and vitamin D has beneficial effects on the improvement of cognitive function in schizophrenic patients.

Natural products and dietary interventions on liver enzymes: an umbrella review and evidence map

Background

The association between natural products and dietary interventions on liver enzymes is unclear; therefore, this study aimed to examine their effects on liver enzymes in adults.

Methods

PubMed, Embase, and Cochrane Library of Systematic Reviews databases were searched from inception until March 2023. The Assessment of Multiple Systematic Reviews-2 (AMSTAR-2) and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) systems were used to assess the methodological and evidence quality, and the therapeutic effects were summarized in a narrative form.

Results

A total of 40 meta-analyses on natural products (n = 25), dietary supplements (n = 10), and dietary patterns (n = 5) were evaluated, and results were presented in a narrative form. The overall methodological quality of the included studies was relatively poor. The results indicated that positive effects were observed for nigella sativa, garlic, artichoke, curcumin, silymarin, vitamin E, vitamin D, L-carnitine, propolis, and polyunsaturated fatty acids on certain liver enzymes. The dietary patterns, including high-protein, Mediterranean, and calorie-restriction diets and evening snacks, may reduce liver enzymes; however, other supplements and herbs did not reduce liver enzyme levels or have minimal effects. The evidence quality was generally weak given the risk of bias, heterogeneity, and imprecision.

Conclusion

This umbrella review suggests that natural products and dietary interventions have beneficial therapeutic effects on liver enzymes levels. Further clinical trials are necessary to establish the effectiveness of supplements that reduce liver enzymes.

Effect of vitamin D supplementation on various parameters in patients with non-alcoholic fatty liver disease: An updated meta-analysis

Aim of the study

The current updated meta-analysis aimed to explore the effects of vitamin D supplementation on various parameters in patients with non-alcoholic fatty liver disease (NAFLD), using the latest trials available.

Material and methods

PubMed, Embase, and the Cochrane Library were screened for the collection of randomized controlled trials (RCTs) that compared the efficacy of additional vitamin D vs. the placebo group on NAFLD patients in the last 5 years. Trials included were focused on the assessment of anthropometric and biochemical indices.

Results

Our results revealed that additional vitamin D greatly increased serum 25-hydroxyvitamin D (25(OH)D), and decreased the low-density lipoprotein-cholesterol (LDL-C) levels. However, no significant differences were found in terms of triglyceride (TG), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), c-glutamyltransferase, fasting blood glucose (FBG), homeostasis model assessment of insulin resistance (HOMA-IR) and Ca2+ levels between the supplementation of vitamin D and placebo.

Conclusions

The present study demonstrated the advantageous impact of supplementary vitamin D on the levels of 25(OH)D and LDL-C in NAFLD patients. However, the results failed to provide evidence for the superiority of additional vitamin D in relation to the concentrations of serum ALP, AST, TC, Ca, γ-glutamyl transferase (GGT), TC, FBG, IR and HDL-C.

The Effect of Vitamin D Supplementation on Lipid Profiles: an Umbrella Review of Meta-Analyses

According to published meta-analyses, vitamin D exerts different beneficial effects in preventing and controlling risk factors associated with noncommunicable chronic diseases; however, the results are still conflicting. The purpose of this umbrella meta-analysis was to investigate the effect of vitamin D supplementation on low-density lipoprotein cholesterol, high-density lipoprotein (HDL) cholesterol, total cholesterol (TC), and triglyceride (TG) as components of the lipid profile. PubMed, Scopus, Web of Science, and Cochrane Database of Systematic Reviews were systematically searched for meta-analyses of randomized controlled trials. The umbrella meta-analysis followed the PRISMA guidelines. The random-effects model was employed to estimate the overall effect size (ES). Overall, 25 meta-analyses were included. In the standardized mean difference analysis, vitamin D significantly decreased TG (ES: -0.15; 95% CI: -0.23, -0.08; P ≤ 0.001) and TC levels (ES: -0.17; 95% CI: -0.23, -0.11; P ≤ 0.001) and increased HDL levels (ES: 0.08; 95% CI: 0.01, 0.15; P = 0.025). In the weighted mean difference analysis, vitamin D significantly decreased only TG levels (ES: -4.63 mg/dL; 95% CI: -7.70, -1.57; P = 0.003). The present study supports that vitamin D supplementation could be considered a beneficial adjuvant therapy in managing lipid profile levels, especially in individuals with vitamin D deficiency. This systematic review was registered in PROSPERO as CRD42022306334.

Potential Therapeutic Strategies in the Treatment of Metabolic-Associated Fatty Liver Disease

Metabolic-associated Fatty Liver Disease is one of the outstanding challenges in gastroenterology. The increasing incidence of the disease is undoubtedly connected with the ongoing obesity pandemic. The lack of specific symptoms in the early phases and the grave complications of the disease require an active approach to prompt diagnosis and treatment. Therapeutic lifestyle changes should be introduced in a great majority of patients; but, in many cases, the adherence is not satisfactory. There is a great need for an effective pharmacological therapy for Metabolic-Associated Fatty Liver Disease, especially before the onset of steatohepatitis. Currently, there are no specific recommendations on the selection of drugs to treat liver steatosis and prevent patients from progression toward more advanced stages (steatohepatitis, cirrhosis, and cancer). Therefore, in this Review, we provide data on the clinical efficacy of therapeutic interventions that might improve the course of Metabolic-Associated Fatty Liver Disease. These include the drugs used in the treatment of obesity and hyperlipidemias, as well as affecting the gut microbiota and endocrine system, and other experimental approaches, including functional foods. Finally, we provide advice on the selection of drugs for patients with concomitant Metabolic-Associated Fatty Liver Disease.

Hepatic vitamin D receptor expression is negatively associated with liver inflammation and fibrosis in patients with chronic HBV infection

The vitamin D receptor (VDR) is a nuclear transcription factor that acts as the main transducer in response to vitamin D (VD), regulating about 3% of the gene expression in the human genome. This study investigated the expression of VDR in the liver of patients with chronic hepatitis B virus (HBV) infection and determined its correlation with liver inflammation and fibrosis. We evaluated the effects of HBV infection on the expression of VDR in vivo and in vitro and further investigate the potential mechanism. Subsequently, the associations between hepatic VDR expression with liver inflammation and fibrosis were statistically analyzed. Results showed that hepatic VDR expression was significantly decreased in patients with chronic HBV infection as compared to healthy individuals. Similarly, in vitro experiments further confirmed that HBV infection could inhibit the expression of VDR in hepatocytes. Mechanistically, HBV was able to directly induce the expression of miR-125a which inhibited the mRNA and protein levels of VDR. Statistical analysis showed that hepatic VDR expression was significantly negatively correlated with liver inflammation and fibrosis in patients. We conclude that inhibition of hepatic vitamin D receptor expression by HBV/miR-125a is negatively associated with liver inflammation and fibrosis in patients with chronic HBV infection.

Vitamin D in atherosclerosis and cardiovascular events

Both experimental and clinical findings linking vitamin D to cardiovascular (CV) risk have prompted consideration of its supplementation to improve overall health. Yet several meta-analyses do not provide support for the clinical effectiveness of this strategy. Meanwhile, the understanding of the roles of vitamin D in the pathophysiology of CV diseases has evolved. Specifically, recent work has revealed some non-classical pleiotropic effects of vitamin D, increasing the complexity of vitamin D signalling. Within particular microenvironments (e.g. dysfunctional adipose tissue and atherosclerotic plaque), vitamin D can act locally at cellular level through intracrine/autocrine/paracrine feedforward and feedback circuits. Within atherosclerotic tissues, 'local' vitamin D levels may influence relevant systemic consequences independently of its circulating pool. Moreover, vitamin D links closely to other signalling pathways of CV relevance including those driving cellular senescence, ageing, and age-related diseases-among them CV conditions. This review updates knowledge on vitamin D biology aiming to clarify the widening gap between experimental and clinical evidence. It highlights the potential reverse causation confounding correlation between vitamin D status and CV health, and the need to consider novel pathophysiological concepts in the design of future clinical trials that explore the effects of vitamin D on atherosclerosis and risk of CV events.

Effect of vitamin D supplementation on type 2 diabetes biomarkers: an umbrella of interventional meta-analyses

BACKGROUND

Vitamin D supplementation exerts several supporting effects on improving glycemic status, however, results are inconclusive. Thus, in the present study, we aimed to conduct an umbrella of meta-analysis regarding the impact of vitamin D on type 2 diabetes (T2DM) biomarkers.

METHODS

The Scopus, PubMed, Web of Science, Embase, and Google Scholar online databases were searched up to March 2022. All meta-analyses evaluating the impact of vitamin D supplementation on T2DM biomarkers were considered eligible. Overall, 37 meta-analyses were included in this umbrella meta-analysis.

RESULTS

Our findings indicated that vitamin D supplementation significantly decreased fasting blood sugar (FBS) (WMD =  - 3.08; 95% CI: - 3.97, - 2.19, p < 0.001, and SMD =  - 0.26; 95% CI: - 0.38, - 0.14, p < 0.001), hemoglobin A1c (HbA1c) (WMD =  - 0.05; 95% CI: - 0.10, - 0.01, p = 0.016, and SMD =  - 0.16; 95% CI: - 0.27, - 0.05, p = 0.004), insulin concentrations (WMD =  - 2.62; 95% CI: - 4.11, - 1.13; p < 0.001, and SMD =  - 0.33; 95% CI: - 0.56, - 0.11, p = 0.004), and homeostatic model assessment for insulin resistance (HOMA-IR) (WMD =  - 0.67; 95% CI: - 1.01, - 0.32, p < 0.001, and SMD =  - 0.31; 95% CI: - 0.46, - 0.16, p < 0.001).

CONCLUSION

This umbrella meta-analysis proposed that vitamin D supplementation may improve T2DM biomarkers.

Non-Alcoholic Fatty Liver Disease and Vitamin D in the UK Biobank: A Two-Sample Bidirectional Mendelian Randomisation Study

Evidence for a role for vitamin D in non-alcoholic fatty liver disease (NAFLD) pathogenesis is conflicting. As Mendelian randomisation (MR) avoids many limitations of conventional observational studies, this two-sample bidirectional MR analysis was conducted to determine the following: (i) whether genetically predicted 25-hydroxyvitamin D [25(OH)D] levels are a risk factor for NAFLD, and (ii) whether genetic risk for NAFLD influences 25(OH)D levels. Single-nucleotide polymorphisms (SNPs) associated with serum 25(OH)D levels were obtained from the European ancestry-derived SUNLIGHT consortium. SNPs associated with NAFLD or NASH (p-value < 1 × 10−5) were extracted from previous studies and supplemented by genome-wide association studies (GWASs) performed in the UK Biobank. These GWASs were done both without (primary analysis) and with (sensitivity analysis) the population-level exclusion of other liver diseases (e.g., alcoholic liver diseases, toxic liver diseases, viral hepatitis, etc.). Subsequently, MR analyses were performed to obtain effect estimates using inverse variance weighted (IVW) random effect models. Cochran’s Q statistic, MR-Egger regression intercept, MR pleiotropy residual sum and outlier (MR-PRESSO) analyses were used to assess pleiotropy. No causal association of genetically predicted serum 25(OH)D (per standard deviation increase) with risk of NAFLD was identified in either the primary analysis: n = 2757 cases, n = 460,161 controls, odds ratio (95% confidence interval): 0.95 (0.76, −1.18), p = 0.614; or the sensitivity analysis. Reciprocally, no causal association was identified between the genetic risk of NAFLD and serum 25(OH)D levels, OR = 1.00 (0.99, 1.02, p = 0.665). In conclusion, this MR analysis found no evidence of an association between serum 25(OH)D levels and NAFLD in a large European cohort.

Lipid accumulation product (LAP) index for the diagnosis of nonalcoholic fatty liver disease (NAFLD): a systematic review and meta-analysis

BACKGROUND

Lipid accumulation product (LAP) is an index calculated by waist circumference (WC) and triglyceride (TG), which reflects lipid toxicity. This study aims to investigate the association between the LAP index and nonalcoholic fatty liver disease (NAFLD) in a systematic review and meta-analysis.

METHODS AND RESULTS

PubMed, Scopus, and Web of Science online databases were searched for eligible studies that investigated the association of the LAP index and NAFLD. Sixteen observational studies with 96,101 participants, including four cohort studies, one case‒control study and 11 cross-sectional studies with baseline data, were entered into this analysis. Fourteen studies reported a significant association between the LAP index and NAFLD, and two reported that this relation was not significant; two different meta-analyses (1- mean difference (MD) and 2- bivariate diagnostic test accuracy [DTA]) were conducted using Stata version 14. The LAP index was compared in subjects with and without NAFLD, and the difference was significant with 34.90 units (CI 95: 30.59-39.31, P < 0.001) of the LAP index. The DTA meta-analysis was conducted and showed that the LAP index pooled sensitivity and specificity for screening of NAFLD were 94% (CI95: 72%-99%, I² = 99%, P < 0.001) and 85% (CI95: 62%-96%, I² = 99%, P < 0.001), respectively.

CONCLUSION

The LAP Index is an inexpensive, sensitive, and specific method to evaluate NAFLD and may be valuable for NAFLD screening.

Vitamin D deficiency in British South Asians, a persistent but avoidable problem associated with many health risks (including rickets, T2DM, CVD, COVID-19 and pregnancy complications): the case for correcting this deficiency

High vitamin D deficiency rates, with rickets and osteomalacia, have been common in South Asians (SAs) arriving in Britain since the 1950s with preventable infant deaths from hypocalcaemic status-epilepticus and cardiomyopathy. Vitamin D deficiency increases common SA disorders (type 2 diabetes and cardiovascular disease), recent trials and non-linear Mendelian randomisation studies having shown deficiency to be causal for both disorders. Ethnic minority, obesity, diabetes and social deprivation are recognised COVID-19 risk factors, but vitamin D deficiency is not, despite convincing mechanistic evidence of it. Adjusting analyses for obesity/ethnicity abolishes vitamin D deficiency in COVID-19 risk prediction, but both factors lower serum 25(OH)D specifically. Social deprivation inadequately explains increased ethnic minority COVID-19 risks. SA vitamin D deficiency remains uncorrected after 70 years, official bodies using 'education', 'assimilation' and 'diet' as 'proxies' for ethnic differences and increasing pressures to assimilate. Meanwhile, English rickets was abolished from ~1940 by free 'welfare foods' (meat, milk, eggs, cod liver oil), for all pregnant/nursing mothers and young children (<5 years old). Cod liver oil was withdrawn from antenatal clinics in 1994 (for excessive vitamin A teratogenicity), without alternative provision. The take-up of the 2006 'Healthy-Start' scheme of food-vouchers for low-income families with young children (<3 years old) has been poor, being inaccessible and poorly publicised. COVID-19 pandemic advice for UK adults in 'lockdown' was '400 IU vitamin D/day', inadequate for correcting the deficiency seen winter/summer at 17.5%/5.9% in White, 38.5%/30% in Black and 57.2%/50.8% in SA people in representative UK Biobank subjects when recruited ~14 years ago and remaining similar in 2018. Vitamin D inadequacy worsens many non-skeletal health risks. Not providing vitamin D for preventing SA rickets and osteomalacia continues to be unacceptable, as deficiency-related health risks increase ethnic health disparities, while abolishing vitamin D deficiency would be easier and more cost-effective than correcting any other factor worsening ethnic minority health in Britain.

The effect of a fruit-rich diet on liver biomarkers, insulin resistance, and lipid profile in patients with non-alcoholic fatty liver disease: a randomized clinical trial

BACKGROUND

Despite confirmed dietary approaches to improve the Non-Alcoholic Fatty Liver Disease (NAFLD), the effect of fruits on NAFLD is not clear. The present study aimed to investigate the effect of a fruit rich diet (FRD) on liver steatosis, liver enzymes, Insulin resistance, and lipid profile in patients with NAFLD.

METHODS

Eighty adults with NAFLD participated in this randomized controlled trial. The participants were randomly assigned to the FRD group with consumption of at least 4 servings of fruits daily or the control group with fruits consumption of less than 2 servings/day. The grade of steatosis, serum levels of liver enzymes including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT), total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), glucose, and homeostatic model assessment for insulin resistance (HOMA-IR) were measured at the baseline and at the end of the study.

RESULTS

After 6 months of intervention, the FRD group had significantly higher BMI (31.40 ± 2.61 vs. 25.68 ± 2.54, p < .001), WC (113.5 ± 10.7 vs. 100.5 ± 7.5, p < .001), the grade of steatosis, ALT (89.1 ± 92.9 vs. 32.0 ± 19.2, p < .001), AST (74.5 ± 107.8 vs. 24.0 ± 8.5, p < .001), ALP (273.4 ± 128.5 vs. 155.0 ± 43.9, p < .001), GGT (92.7 ± 16.2 vs. 21.2 ± 7.7, p < .001), TC (206.1 ± 40.5 vs. 172.7 ± 42.4, p < .01), LDL (126.9 ± 32.3 vs. 99.8 ± 29.8, p < .001), glucose (115.5 ± 30.0 vs. 97.7 ± 19.0, p < .01), and insulin resistance (7.36 ± 4.37 vs. 2.66 ± 1.27, p < .001), and lower HDL (41.4 ± 8.9 vs. 53.8 ± 15.1, p < .001) compared to the control group. Adjusting for BMI and calorie intake did not change the results.

CONCLUSION

The results of the present study indicated that consumption of fruits more than 4 servings/day exacerbates steatosis, dyslipidemia, and glycemic control in NAFLD patients. Further studies are needed to identify the underlying mechanisms of the effects of fruits on NAFLD.

CLINICAL TRIAL REGISTRATION

This trial was registered at Iranian randomized clinical trial website with IRCT registration no. IRCT20201010048982N1on October 15, 2020.

Higher Serum 25-Hydroxyvitamin D Is Associated with Lower All-Cause and Cardiovascular Mortality among US Adults with Nonalcoholic Fatty Liver Disease

Aims: We aimed to assess the association between serum 25-hydroxyvitamin D (25(OH)D) levels with all-cause and cardiovascular mortality in patients with nonalcoholic fatty liver disease (NAFLD). Methods: We performed a retrospective cohort study based on the US National Health and Nutrition Examination Survey 2001–2016 on adults aged ≥20 years. NAFLD was determined as a US Fatty Liver Index score ≥ 30 in the absence of other liver conditions. Weighted Cox proportional hazards regression models were applied to explore the relationship between serum 25(OH)D levels and mortality. Results: 898 all-cause deaths and 305 cardiovascular deaths were recorded over a median follow-up of 8.7 years. Compared with those in the severe deficiency group (below 25.0 nmol/L), the fully adjusted HRs and 95% CIs of NAFLD patients with sufficient serum 25(OH)D concentrations (≥75.0 nmol/L) were 0.36 (0.22, 0.60) for all-cause mortality and 0.14 (0.07, 0.29) for cardiovascular mortality. Each one-unit increase in the natural log-transformed serum 25(OH)D concentration was related to a 41% lower risk for all-cause deaths (HR = 0.59, 95% CI: 0.46, 0.77) and a 65% lower risk for cardiovascular deaths (HR = 0.35, 95% CI: 0.22, 0.58). Conclusions: Among NAFLD patients, increased serum 25(OH)D levels were independently associated with reduced risk for all-cause and cardiovascular deaths.

Association between serum 25-hydroxy vitamin D concentrations and mortality among individuals with metabolic dysfunction-associated fatty liver disease: a prospective cohort study

BACKGROUND

The association between serum 25-hydroxy vitamin D (25(OH)D) concentrations and mortality remains unclear among patients with metabolic dysfunction-associated fatty liver disease (MAFLD) or non-alcoholic fatty liver disease (NAFLD).

OBJECTIVES

To evaluate the association between serum 25(OH)D concentrations and mortality among individuals with MAFLD/NAFLD.

METHODS

The study included 4651 individuals with fatty liver disease (FLD) (3964 had MAFLD and 3968 had NAFLD) from the Third National Health and Nutrition Examination Survey. Fatty liver disease was identified by ultrasonographic detection of hepatic steatosis. Mortality was ascertained by linkage to the National Death Index up to 31 December 2019. Cox proportional hazards models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) with adjustment of potential confounders.

RESULTS

Of 4651 individuals with FLD, 3427 individuals (69.7%) had both MAFLD and NAFLD. During median follow-ups of 25.8 and 26.1 years, we identified 1809 and 1665 deaths among 3964 participants with MAFLD and 3968 participants with NAFLD, respectively. Compared with participants with serum 25(OH)D concentrations ≤30.0 nmol/L, the multivariable-adjusted HR and 95% CI of all-cause mortality were 0.62 (0.43, 0.89) for participants with MAFLD having serum 25(OH)D >75.0 nmol/L (P-trend = 0.001), and 0.63 (0.42, 0.95) for participants with NAFLD having serum 25(OH)D >75.0 nmol/L (P-trend = 0.002). A nonlinearly inverse association was observed between serum 25(OH)D concentrations and all-cause mortality among participants with MAFLD (Poverall <0.001; Pnonlinear = 0.003) or NAFLD (Poverall <0.001; Pnonlinear = 0.009), with a threshold effect at around 50.0 nmol/L. The inverse association was stronger among participants with MAFLD aged <60 years (P-interaction = 0.001).

CONCLUSIONS

This study suggested a nonlinearly inverse association between serum 25(OH)D concentrations and all-cause mortality among patients with MAFLD/NAFLD, with a threshold effect at around 50.0 nmol/L of serum 25(OH)D.

Vitamin D supplementation positively affects anthropometric indices: Evidence obtained from an umbrella meta-analysis

Despite the growing evidence from meta-analyses on vitamin D’s anti-obesity properties, their results are controversial. The current umbrella review was performed to assess the available evidence and provide a conclusive explanation in this regard. The international databases PubMed, Scopus, Embase, Web of Science and Google Scholar were systematically searched till March, 2022. A random-effects model was used to run the meta-analysis. All meta-analyses that examined the effect of vitamin D supplementation on BW, BMI, WC, and fat mass were included. Findings of 14 meta-analyses revealed that vitamin D supplementation reduced body mass index (BMI) (ES: −0.11 kg/m²; 95% CI: −0.18, −0.05, p?0.001; I² = 61.0%, p < 0.001), and waist circumference (WC) (ES = −0.79 cm; 95% CI: −1.20, −0.37; p < 0.001; I² = 46.5%, p = 0.096) in comparison to control group. However, the effects of vitamin D on body weight (ES = −0.16 kg, 95% CI: −0.36, 0.04; p = 0.125; I² = 57.0%, p = 0.017), and fat mass (ES: 0.02, 95% CI: −0.20, 0.24, p = 0.868; I² = 0.0%, p = 0.531) were not considerable. Vitamin D supplementation significantly improved levels of obesity indices such as BMI, and WC.

Vitamin D–VDR Novel Anti-Inflammatory Molecules—New Insights into Their Effects on Liver Diseases

There is consistent evidence that vitamin D deficiency is strongly associated with liver dysfunction, disease severity, and poor prognosis in patients with liver disease. Vitamin D and its receptor (VDR) contribute to the regulation of innate and adaptive immune responses. The presence of genetic variants of vitamin D- and VDR-associated genes has been associated with liver disease progression. In our recent work, we summarized the progress in understanding the molecular mechanisms involved in vitamin D–VDR signaling and discussed the functional significance of VDR signaling in specific cell populations in liver disease. The current review focuses on the complex interaction between immune and liver cells in the maintenance of liver homeostasis and the development of liver injury, the interplay of vitamin D and VDR in the development and outcome of liver disease, the role of vitamin D- and VDR-associated genetic variants in modulating the occurrence and severity of liver disease, and the therapeutic value of vitamin D supplementation in various liver diseases. The association of the vitamin D–VDR complex with liver dysfunction shows great potential for clinical application and supports its use as a prognostic index and diagnostic tool.

The Association Between Vitamin D and Type 2 Diabetes Mellitus Complicated with Non-Alcoholic Fatty Liver Disease: An Observational Cross-Sectional Study

OBJECTIVE

To investigate the association between vitamin D deficiency and NAFLD risk in patients with type 2 diabetes mellitus (T2DM).

METHODS

Overall, 434 patients with T2DM admitted to Hebei General Hospital from January 2019 to December 2019 were selected as the study subjects. According to abdominal ultrasound findings, patients were divided into the NAFLD group and the non-NAFLD group. Participants were divided into two study groups according to the 25-hydroxyvitamin D [25(OH)D] level. 25(OH)D deficiency was defined if 25(OH)D vitamin levels were <20 ng/mL. Chi-square test and one-way analysis of variance were used to compare groups. The relationship between 25(OH)D and NAFLD risk was analyzed using correlation and regression analyses. Furthermore, subgroup analyses were performed to verify the robustness of the results.

RESULTS

The 25(OH)D level in patients with T2DM complicated by NAFLD was significantly lower than in patients with T2DM only. Vitamin D deficiency was highly prevalent among T2DM patients with NAFLD. This study suggested that vitamin D deficiency was an independent factor for developing NAFLD in patients with T2DM. T2DM patients with vitamin D deficiency had 2.045 times higher risk of developing NAFLD than those without vitamin D deficiency. Vitamin D deficiency was associated with high NAFLD preference in T2DM patients with BMI >23kg/m², but not those with BMI ≤23kg/m². The significant correlation between vitamin D deficiency and NAFLD was found in participants with BMI >23kg/m², age ≤65 years, without hypertension, TG <1.7mmol/l, HDL ≥1 mmol/l in men, ≥1.3 mmol/l in women, HBA1C ≤7%, or females.

CONCLUSION

This study suggests that T2DM people with BMI >23kg/m² were more susceptible to NAFLD by vitamin D deficiency and that it is necessary to maintain optimal serum vitamin D levels in this population.