Vitamin D supplementation could reduce the risk of acute cellular rejection and infection in vitamin D deficient liver allograft recipients

Vitamin D: A Bridge between Kidney and Heart

Chronic kidney disease (CKD) and cardiovascular disease (CVD) are highly prevalent conditions, each significantly contributing to the global burden of morbidity and mortality. CVD and CKD share a great number of common risk factors, such as hypertension, diabetes, obesity, and smoking, among others. Their relationship extends beyond these factors, encompassing intricate interplay between the two systems. Within this complex network of pathophysiological processes, vitamin D has emerged as a potential linchpin, exerting influence over diverse physiological pathways implicated in both CKD and CVD. In recent years, scientific exploration has unveiled a close connection between these two prevalent conditions and vitamin D, a crucial hormone traditionally recognized for its role in bone health. This article aims to provide an extensive review of vitamin D's multifaceted and expanding actions concerning its involvement in CKD and CVD.

Evaluation of Vitamin D Levels in Children With Liver Transplant

OBJECTIVES

Vitamin D deficiency is common in pediatric chronic liver disease despite oral replacement. We evaluated vitamin D deficiency before and after liver transplant and the relationship between posttransplant and pretransplant vitamin D deficiency and graft rejection.

MATERIALS AND METHODS

Pediatric recipients with chronic liver disease (N =138) were divided into 4 groups: cholestatic liver diseases, cirrhosis, metabolic disorders, and acute liver failure. Pretransplant and posttransplant vitamin D levels, liver function tests, Pediatric End-Stage Liver Disease scores, rejection activity index scores by graft liver biopsy, and posttransplant patient survival were recorded.

RESULTS

There were 62 (45%) female and 76 (55%) male participants (mean transplant age, 6.1 ± 5.6 years). Pretransplant mean available vitamin D of 90 patients was 25.2 ± 20.9 ng/mL, with 36 (40%) within reference range. Posttransplant level for 109 patients was 27.3 ± 18 ng/mL, with 64 (58.7%) within reference range. Pretransplant and posttransplant levels were available for 61 patients, and mean pretransplant levels were lower than posttransplant levels (23.7 ± 19.3 vs 28.3 ± 16.9 ng/mL; P = .01). Patients with cholestatic liver disease had lower pretransplant vitamin D levels (P = .04), which disappeared after transplant. Pretransplant vitamin D levels were positively correlated with serum albumin levels (r = 0.20) in all patients and negatively correlated with total/direct bilirubin (r = 0.29 and r = -0.30) in those with liver diseases and cirrhosis. No correlations were found between pretransplant vitamin D levels and Pediatric End-Stage Liver Disease scores, rejection activity index scores, and posttransplant mortality.

CONCLUSIONS

Vitamin D deficiency is prevalent in pediatric chronic liver disease before and after transplant, especially for cholestatic liver diseases. However, no association between vitamin D levels and liver graft rejection or patient survival was noted. We recommend close monitoring and individualized vitamin D supplementation before and after liver transplant.

Impact of air pollution on postoperative outcomes following organ transplantation: Evidence from clinical investigations

INTRODUCTION

Air pollution is a worldwide problem affecting human health via various body systems, resulting in numerous significant adverse events. Air pollutants, including particulate matter < or = 2.5 microns (PM2.5), particulate matter < or = 10 microns (PM10), ozone (O3 ), nitrogen dioxide (NO2 ), and traffic-related air pollution (TRAP), have demonstrated the negative effects on human health (e.g., increased cerebrovascular, cardiovascular, and respiratory diseases, malignancy, and mortality). Organ transplant patients, who are taking immunosuppressive agents, are especially vulnerable to the adverse effects of air pollutants. The evidence from clinical investigation has shown that exposure to air pollution after organ transplantation is associated with organ rejection, cardiovascular disease, coronary heart disease, cerebrovascular disease, infection-related mortality, and vitamin D deficiency.

OBJECTIVES AND METHOD

This review aims to summarize and discuss the association of exposure to air pollutants and serum 25-hydroxyvitamin D level and outcomes after transplantation. Controversial findings are also included and discussed.

CONCLUSION

All of the findings suggest that air pollution results in a hazardous environment, which not only impacts human health worldwide but also affects post-transplant outcomes.

Vitamin D status as a predictor for liver transplant outcomes

It is well known that vitamin D plays a pivotal role in immune system modulation; however, its role in liver transplantation (LT) has not yet been well elucidated. This study aimed to assess the association between vitamin D status and LT outcomes. This retrospective cohort study was conducted on 335 registered cirrhotic patients with end-stage liver disease (ESLD) who underwent LT during 2019-2021 and had measurement of serum vitamin D before LT. The association of vitamin D levels before LT with the odds of acute cellular rejection (ACR) and risk mortality was assessed by applying logistic and cox regression, respectively. The mean MELD-Na and serum level of vitamin D were 20.39 ± 9.36 and 21.52 ± 15.28 ng/ml, respectively. In the final adjusted model, there was a significant association between vitamin D deficiency in the pre-transplant period and odds of ACR (odds ratio [OR] 2.69; 95% confidence interval [CI] 1.50-4.68). Although in the crude model, vitamin D deficiency in the pre-transplant period was significantly associated with an increased risk of mortality after two years of follow-up (Hazard ratio (HR) = 2.64, 95% CI 1.42-4.33), after adjustment for potential confounders, the association of vitamin D status and mortality became non-significant (HR = 1.46, 95% CI 0.71-3.00). The present study provides evidence that pre-transplant serum vitamin D levels may be a predictor for ACR in patients with cirrhosis undergoing LT.

Comorbidities and clinical complications associated with SARS-CoV-2 infection: an overview

The novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes major challenges to the healthcare system. SARS-CoV-2 infection leads to millions of deaths worldwide and the mortality rate is found to be greatly associated with pre-existing clinical conditions. The existing dataset strongly suggests that cardiometabolic diseases including hypertension, coronary artery disease, diabetes and obesity serve as strong comorbidities in coronavirus disease (COVID-19). Studies have also shown the poor outcome of COVID-19 in patients associated with angiotensin-converting enzyme-2 polymorphism, cancer chemotherapy, chronic kidney disease, thyroid disorder, or coagulation dysfunction. A severe complication of COVID-19 is mostly seen in people with compromised medical history. SARS-CoV-2 appears to attack the respiratory system causing pneumonia, acute respiratory distress syndrome, which lead to induction of severe systemic inflammation, multi-organ dysfunction, and death mostly in the patients who are associated with pre-existing comorbidity factors. In this article, we highlighted the key comorbidities and a variety of clinical complications associated with COVID-19 for a better understanding of the etiopathogenesis of COVID-19.

Interplay of Vitamin D and SIRT1 in Tissue-Specific Metabolism-Potential Roles in Prevention and Treatment of Non-Communicable Diseases Including Cancer

The importance of the prevention and control of non-communicable diseases, including obesity, metabolic syndrome, type 2 diabetes, cardiovascular diseases, and cancer, is increasing as a requirement of the aging population in developed countries and the sustainability of healthcare. Similarly, the 2013-2030 action plan of the WHO for the prevention and control of non-communicable diseases seeks these achievements. Adequate lifestyle changes, alone or with the necessary treatments, could reduce the risk of mortality or the deterioration of quality of life. In our recent work, we summarized the role of two central factors, i.e., appropriate levels of vitamin D and SIRT1, which are connected to adequate lifestyles with beneficial effects on the prevention and control of non-communicable diseases. Both of these factors have received increased attention in relation to the COVID-19 pandemic as they both take part in regulation of the main metabolic processes, i.e., lipid/glucose/energy homeostasis, oxidative stress, redox balance, and cell fate, as well as in the healthy regulation of the immune system. Vitamin D and SIRT1 have direct and indirect influence of the regulation of transcription and epigenetic changes and are related to cytoplasmic signaling pathways such as PLC/DAG/IP3/PKC/MAPK, MEK/Erk, insulin/mTOR/cell growth, proliferation; leptin/PI3K-Akt-mTORC1, Akt/NFĸB/COX-2, NFĸB/TNFα, IL-6, IL-8, IL-1β, and AMPK/PGC-1α/GLUT4, among others. Through their proper regulation, they maintain normal body weight, lipid profile, insulin secretion and sensitivity, balance between the pro- and anti-inflammatory processes under normal conditions and infections, maintain endothelial health; balance cell differentiation, proliferation, and fate; and balance the circadian rhythm of the cellular metabolism. The role of these two molecules is interconnected in the molecular network, and they regulate each other in several layers of the homeostasis of energy and the cellular metabolism. Both have a central role in the maintenance of healthy and balanced immune regulation and redox reactions; therefore, they could constitute promising targets either for prevention or as complementary therapies to achieve a better quality of life, at any age, for healthy people and patients under chronic conditions.

Nutritional Strategies to Manage Malnutrition and Sarcopenia following Liver Transplantation: A Narrative Review

Persisting or newly developed malnutrition and sarcopenia after liver transplant (LT) are correlated with adverse health outcomes. This narrative review aims to examine the literature regarding nutrition strategies to manage malnutrition and sarcopenia after LT. The secondary aims are to provide an overview of the effect of nutrition strategies on the incidence of infections, hospital length of stay (LOS), acute cellular rejection (ACR), and mortality after LT. Four databases were searched. A total of 25 studies, mostly of mid-high quality, were included. Six studies found a beneficial effect on nutritional parameters using branched-chain amino acids (BCAA), immunomodulating diet (IMD), or enteral nutrition (EN) whereas two studies using beta-hydroxy-beta-methylbutyrate (HMB) found a beneficial effect on muscle mass and function. Fourteen studies using pre- or pro-biotics, IMD, and EN were effective in lowering infection and six studies using IMD, BCAA or HMB reported reduced hospital LOS. Finally, four studies using HMB and vitamin D were effective in reducing ACR and one study reported reduced mortality using vitamin D after LT. In conclusion, nutritional intervention after LT has different beneficial effects on malnutrition, sarcopenia, and other advert outcomes. Additional large and well-constructed RCTs using validated tools to assess nutritional status and sarcopenia are warranted to ensure more robust conclusions.

Age-related changes in peripheral T-cell subpopulations in elderly individuals: An observational study

The age-related decline in T-cell function among elderly individuals remains unclear. We thus investigated the interrelationship between T-cell subsets and age to identify the changes in T-cell phenotypes and develop an age prediction model for the elderly population. A total of 127 individuals aged >60 years were divided into three groups (youngest-old group, 61-70 years, n = 34; middle-old group, 71-80 years, n = 53; and oldest-old group, ≥ 81 years, n = 40). The percentage of CD8+CD28- cells (P = 0.001) was highest in the oldest-old group and then followed by the middle-old group, while the youngest-old group was the lowest. Both females and males demonstrated significant decreases in the absolute counts of CD4+CD45RA+ cells (P = 0.020; P = 0.002) and CD8+CD28+ cells (P = 0.015; P = 0.005) with age. Multivariate linear regression showed that the percentage of CD8+CD28- cells (P < 0.001) was an independent predictor of aging after adjusting for sex, body mass index, hospitalization duration, smoking, drinking, chronic medical illness, and medications at admission. In conclusion, our results suggest that aging in elderly individuals is accompanied by a decrease in the counts of T-cell subpopulations. CD8+CD28- cells may be potential targets for elderly individuals in antiaging-related immunosenescence.

Incidence of malnutrition and changes in phosphocalcic metabolism in perioperative liver transplantation patients -a retrospective study in a tertiary children's hospital in China

BACKGROUND

The primary aim of the study was to assess the nutritional status of pediatric liver transplant outpatients in nutrition clinic, particularly the nutritional status of their bones.  METHODS: One hundred thirty-eight pediatric liver transplant outpatients, who had visited the nutrition clinic in Shanghai Children's Medical Center between January 2017 and December 2019, were recruited. The bone mineral density (BMD) z-scores were determined by dual energy X-ray absorptiometry (DXA). Nutritional assessment was performed, and their corresponding height-for-age z-scores (HAZs)/weight-for-age z-scores (WAZs)/BMI-for-age z-scores (BMIZs) were obtained.

RESULTS

A total of 138 patients came to our nutrition outpatient clinic, including 68 boys (49.3%) and 70 girls (50.7%). The median age was 0.87y (0.68y, 1.71y). Among these patients, 44 (31.9%) had acute malnutrition with WAZ/BMIZ value -1.14 (-2.38, -0.18), 55 (38.4%) had chronic malnutrition with HAZ value -1.51 (-2.39, -0.38), and 96 (69.6%) had a BMD lower than normal. The BMD z-score was significantly correlated with the WAZ/BMIZ value (Spearman's correlation coefficient = 0.334, p < 0.001). A total of 37 infants re-visited the nutrition clinic for a follow-up after (147 ± 127) days. The WAZ/BMIZ value of the re-visiting patients and the BMD z-score of the re-visiting patients were significantly improved compared to those of the first-visit patients (p = 0.004 and p = 0.001 respectively).

CONCLUSIONS

There were different rates of malnutrition before and after liver transplantation. At the same time, BMD Z-score and serum vitamin D level of patients decreased. There was a significant correlation between BMD z-scores and WAZ/BMIZ values. Proper and professional nutrition guidance significantly improved the WAZ/BMIZ-values and BMD Z-score of liver transplantation patients.

Liver Graft Pathology and Low Serum 25-Hydroxyvitamin D after Living Donor Liver Transplantation

BACKGROUND

Most cases of advanced liver diseases are associated with low serum 25-hydroxyvitamin D and vitamin D deficiency. This phenomenon may occur in living donor liver transplantation (LDLT).

AIMS

We conducted this study to explore the interplay between VDR and CYP2R1 in liver graft and compared our findings with the pathological interpretation of serum 25(OH)D concentration.

METHODS

In total, 60 patients received liver graft biopsy after LDLT and were separated (1:1) into two groups: graft rejection group and graft non-rejection group. We extracted both of the recipients' and donors' serum DNA to investigate the vitamin D receptor (VDR) rs2228530 and CYP2R1 rs10741657 single nucleotide polymorphisms (SNPs) using real-time polymerase chain reaction. We also extracted DNA from liver graft tissues to explore the genetic alleles of VDR rs2228530 and CYP2R1 rs10741657 after LDLT. Serum biochemistry profile and 25(OH)D concentrations were measured before and after LDLT.

RESULTS

There were no significant differences in serum VDR rs2228530 and CYP2R1 rs10741657 genetic alleles between recipients and donors. The percentage of genetic modification was 33.4% (10/30) for the rejection and non-rejection groups in VDR rs2228530, and 66.7% (20/30) for both groups in CYP2R1 rs10741657. Serum 25(OH)D concentrations were significantly lower after LDLT D30 than that before LDLT in the rejection (p = 0.0001) and non-rejection graft pathology (p = 0.0017) groups.

CONCLUSIONS

The presence of low serum 25(OH)D concentrations after LDLT suggested that post-transplant low serum 25(OH)D concentrations may develop with the homogenous phenomenon of VDR rs2228530 and CYP2R1 rs10741657 genetic modifications in recipients regardless of graft pathology.

A New Generation of Cell Therapies Employing Regulatory T Cells (Treg) to Induce Immune Tolerance in Pediatric Transplantation

Kidney transplantation is the most common solid organ transplant and the preferred treatment for pediatric patients with end-stage renal disease, but it is still not a definitive solution due to immune graft rejection. Regulatory T cells (Treg) and their control over effector T cells is a crucial and intrinsic tolerance mechanism in limiting excessive immune responses. In the case of transplants, Treg are important for the survival of the transplanted organ, and their dysregulation could increase the risk of rejection in transplanted children. Chronic immunosuppression to prevent rejection, for which Treg are especially sensitive, have a detrimental effect on Treg counts, decreasing the Treg/T-effector balance. Cell therapy with Treg cells is a promising approach to restore this imbalance, promoting tolerance and thus increasing graft survival. However, the strategies used to date that employ peripheral blood as a Treg source have shown limited efficacy. Moreover, it is not possible to use this approach in pediatric patients due to the limited volume of blood that can be extracted from children. Here, we outline our innovative strategy that employs the thymus removed during pediatric cardiac surgeries as a source of therapeutic Treg that could make this therapy accessible to transplanted children. The advantageous properties and the massive amount of Treg cells obtained from pediatric thymic tissue (thyTreg) opens a new possibility for Treg therapies to prevent rejection in pediatric kidney transplants. We are recruiting patients in a clinical trial to prevent rejection in heart-transplanted children through the infusion of autologous thyTreg cells (NCT04924491). If its efficacy is confirmed, thyTreg therapy may establish a new paradigm in preventing organ rejection in pediatric transplants, and their allogeneic use would extend its application to other solid organ transplantation.

The Role of Vitamin Deficiency in Liver Disease: To Supplement or Not Supplement?

Over the past few years, growing interest has been shown for the impact of dietary requirements and nutritional factors on chronic diseases. As a result, nutritional programs have been reinforced by public health policies. The precise role of micronutrients in chronic liver disease is currently receiving particular attention since abnormalities in vitamin levels are often detected. At present, treatment programs are focused on correcting vitamin deficiencies, which are frequently correlated to higher rates of comorbidities with poor outcomes. The literature reviewed here indicates that liver diseases are often related to vitamin disorders, due to both liver impairment and abnormal intake. More specific knowledge about the role of vitamins in liver disease is currently emerging from various results and recent evidence. The most significant benefits in this area may be observed when improved vitamin intake is combined with a pharmacological treatment that may also affect the progression of the liver disease, especially in the case of liver tumors. However, further studies are needed.

Prevalence of vitamin D deficiency and impact on clinical outcomes after kidney transplantation: a systematic review and meta-analysis

CONTEXT

The prevalence of vitamin D deficiency (VDD) and its impact on clinical outcomes after kidney transplant (KT) remain poorly defined.

OBJECTIVES

We conducted a meta-analysis to evaluate the impact of early VDD on clinical outcomes after KT.

DATA SOURCES

Electronic databases (PubMed, Embase, Web of Science, and The Cochrane Library) were systematically searched for eligible publications up to April 30, 2020.

DATA EXTRACTION

Relative risk was presented as hazard ratios (HRs) or odds ratios (ORs) and 95%CIs for dichotomous outcomes. Mean difference (MD) and 95%CIs were presented for continuous outcomes.

RESULTS

A total of 28 studies (13 prospective and 15 retrospective) were included. VDD was common early after KT, with a prevalence of 52% (95%CI: 41%-64%) at transplant, 34% (95%CI: 17%-51%) at 3 months, and 23% (95%CI: 10%-35%) at 6 months. Early VDD was associated with higher mortality rate after KT (HR, 1.56; 95%CI: 1.32-1.84; P < 0.001). In addition, early VDD led to higher risk of bacterial infection (OR, 1.82; 95%CI: 1.40-2.36; P < 0.001), BK polyomavirus infection (OR, 2.11, 95%CI: 1.23-3.61; P = 0.006), and cytomegalovirus infection (OR, 1.69; 95%CI: 1.24-2.31; P = 0.001). Early VDD increased the risk of acute rejection as well (HR, 2.28; 95%CI: 1.57-3.30; P < 0.001). Recipients with early VDD had lower estimated glomerular filtration rates (mean difference: -5.06; 95%CI: -7.28 to 2.83 mL/min; P < 0.001). Sensitivity analyses showed good stability of the pooled results.

CONCLUSION

VDD was common early after KT and associated with higher risk of death and adverse outcomes.

Vitamin D supplementation for chronic liver diseases in adults

BACKGROUND

Vitamin D deficiency is often reported in people with chronic liver diseases. Improving vitamin D status could therefore be beneficial for people with chronic liver diseases.

OBJECTIVES

To assess the beneficial and harmful effects of vitamin D supplementation in adults with chronic liver diseases.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, LILACS, Science Citation Index Expanded, and Conference Proceedings Citation Index-Science. We also searched ClinicalTrials.gov  and the World Health Organization International Clinical Trials Registry Platform. We scanned bibliographies of relevant publications and enquired experts and pharmaceutical companies as to additional trials. All searches were up to November 2020.

SELECTION CRITERIA

Randomised clinical trials that compared vitamin D at any dose, duration, and route of administration versus placebo or no intervention in adults with chronic liver diseases. Vitamin D could have been administered as supplemental vitamin D (vitamin D₃ (cholecalciferol) or vitamin D₂ (ergocalciferol)), or an active form of vitamin D (1α-hydroxyvitamin D (alfacalcidol), 25-hydroxyvitamin D (calcidiol), or 1,25-dihydroxyvitamin D (calcitriol)).

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included 27 randomised clinical trials with 1979 adult participants. This review update added 12 trials with 945 participants. We assessed all trials as at high risk of bias. All trials had a parallel-group design. Eleven trials were conducted in high-income countries and 16 trials in middle-income countries. Ten trials included participants with chronic hepatitis C, five trials participants with liver cirrhosis, 11 trials participants with non-alcoholic fatty liver disease, and one trial liver transplant recipients. All of the included trials reported the baseline vitamin D status of participants. Participants in nine trials had baseline serum 25-hydroxyvitamin D levels at or above vitamin D adequacy (20 ng/mL), whilst participants in the remaining 18 trials were vitamin D insufficient (less than 20 ng/mL). Twenty-four trials administered vitamin D orally, two trials intramuscularly, and one trial intramuscularly and orally. In all 27 trials, the mean duration of vitamin D supplementation was 6 months, and the mean follow-up of participants from randomisation was 7 months. Twenty trials (1592 participants; 44% women; mean age 48 years) tested vitamin D₃ (cholecalciferol); three trials (156 participants; 28% women; mean age 54 years) tested vitamin D₂; four trials (291 participants; 60% women; mean age 52 years) tested 1,25-dihydroxyvitamin D; and one trial (18 participants; 0% women; mean age 52 years) tested 25-hydroxyvitamin D. One trial did not report the form of vitamin D. Twelve trials used a placebo, whilst the other 15 trials used no intervention in the control group. Fourteen trials appeared to be free of vested interest. Eleven trials did not provide any information on clinical trial support or sponsorship. Two trials were funded by industry. We are very uncertain regarding the effect of vitamin D versus placebo or no intervention on all-cause mortality (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.51 to 1.45; 27 trials; 1979 participants). The mean follow-up was 7 months (range 1 to 18 months). We are very uncertain regarding the effect of vitamin D versus placebo or no intervention on liver-related mortality (RR 1.62, 95% CI 0.08 to 34.66; 1 trial; 18 participants) (follow-up: 12 months); serious adverse events such as hypercalcaemia (RR 5.00, 95% CI 0.25 to 100.8; 1 trial; 76 participants); myocardial infarction (RR 0.75, 95% CI 0.08 to 6.81; 2 trials; 86 participants); thyroiditis (RR 0.33, 95% CI 0.01 to 7.91; 1 trial; 68 participants); circular haemorrhoidal prolapse (RR 3.00, 95% CI 0.14 to 65.9; 1 trial; 20 participants); bronchopneumonia (RR 0.33, 95% CI 0.02 to 7.32; 1 trial 20 participants); and non-serious adverse events. The certainty of evidence for all outcomes is very low. We found no data on liver-related morbidity such as gastrointestinal bleeding, hepatic encephalopathy, hepatorenal syndrome, ascites, or liver cancer. There were also no data on health-related quality of life. The evidence is also very uncertain regarding the effect of vitamin D versus placebo or no intervention on rapid, early, and sustained virological response in people with chronic hepatitis C.

AUTHORS' CONCLUSIONS

Given the high risk of bias and insufficient power of the included trials and the very low certainty of the available evidence, vitamin D supplementation versus placebo or no intervention may increase or reduce all-cause mortality, liver-related mortality, serious adverse events, or non-serious adverse events in adults with chronic liver diseases. There is a lack of data on liver-related morbidity and health-related quality of life. Further evidence on clinically important outcomes analysed in this review is needed.

Vitamin D Insufficiency Prior to Paediatric Liver Transplantation Is Associated with Early T-Cell Mediated Rejection

Objectives: T-cell mediated rejection (TCMR) can compromise long-term liver allograft survival. The immunomodulatory properties of vitamin D are increasingly recognized. We investigated whether perturbations in vitamin D metabolism prior to LT may predispose to TCMR in a representative cohort of paediatric LT recipients. Methods: In this retrospective single-center study of children who underwent liver transplantation between 2005 and 2017, we collected serum 25(OH) vitamin D levels and other parameters related to vitamin D metabolism. Post-transplant variables were collected from medical records during the first year following LT. Results: Eighty-two patients were included. Twenty-six (32%) developed TCMR, 52 (65%) presented at least one event of 25(OH) D insufficiency during the year before the transplant, while 23 (32%) had at least one documented elevated plasma parathyroid hormone level. Forty-six patients benefited from nutritional support (56%). The development of TCMR was associated with vitamin D insufficiency pre-LT (p = 0.01). No significant correlations were identified between PTH levels and incidence of TCMR. The association was stronger in patients transplanted for cholestatic diseases (p = 0.004). Conclusions: Vitamin D insufficiency before a liver transplant may be associated with TCMR during the first year post-LT. These findings warrant further investigation.

The Presence of a Marked Imbalance Between Regulatory T Cells and Effector T Cells Reveals That Tolerance Mechanisms Could Be Compromised in Heart Transplant Children

Regulatory T cells (Treg) are crucial for the induction and maintenance of graft tolerance. In pediatric heart transplant procedures, the thymus is routinely excised, removing the primary source of T-cell replenishment. Consequently, thymectomy joined to the effects of immunosuppression on the T-cell compartment may have a detrimental impact on Treg values, compromising the intrinsic tolerance mechanisms and the protective role of Treg preventing graft rejection in heart transplant children.

Combination of vitamin D and dipeptidyl peptidase-4 inhibitors (VIDPP-4i) as an immunomodulation therapy for autoimmune diabetes

Type 1 diabetes (T1D) and latent autoimmune diabetes in adults (LADA) represent the most common types of autoimmune diabetes and are characterized by different age of onset, degrees of immune-mediated destruction of pancreatic beta cells and rates of disease progression towards insulin dependence. Several immunotherapies aimed to counteract autoimmune responses against beta cells and preserve beta-cell function are currently being investigated, particularly in T1D. Preliminary findings suggest a potential role of combination therapy with vitamin D and dipeptidyl peptidase-4 (DPP-4) inhibitors (VIDPP-4i) in preserving beta-cell function in autoimmune diabetes. This manuscript aims to provide a comprehensive overview of the immunomodulatory properties of vitamin D and DPP-4 inhibitors, as well as the rationale for investigation of their combined use as an immunomodulation therapy for autoimmune diabetes.

Nutrition Support in Liver Transplantation and Postoperative Recovery: The Effects of Vitamin D Level and Vitamin D Supplementation in Liver Transplantation

Vitamin D plays an important role in the arena of liver transplantation. In addition to affecting skeletal health significantly, it also clinically exerts immune-modulatory properties. Vitamin D deficiency is one of the nutritional issues in the perioperative period of liver transplantation (LT). Although vitamin D deficiency is known to contribute to higher incidences of acute cellular rejection (ACR) and graft failure in other solid organ transplantation, such as kidneys and lungs, its role in LT is not well understood. The aim of this study was to investigate the clinical implication of vitamin D deficiency in LT. LT outcomes were reviewed in a retrospective cohort of 528 recipients during 2014-2019. In the pre-transplant period, 55% of patients were vitamin-D-deficient. The serum vitamin D level was correlated with the model for end-stage liver disease (MELD-Na) score. Vitamin D deficiency in the post-transplant period was associated with lower survival after LT, and the post-transplant supplementation of vitamin D was associated with a lower risk of ACR. The optimal vitamin D status and vitamin D supplementation in the post-transplant period may prolong survival and reduce ACR incidence.

Vitamin D deficiency 2.0: an update on the current status worldwide

Vitamin D testing and the use of vitamin D supplements have increased substantially in recent years. Currently, the role of vitamin D supplementation, and the optimal vitamin D dose and status, is a subject of debate, because large interventional studies have been unable to show a clear benefit (in mostly vitamin D replete populations). This may be attributed to limitations in trial design, as most studies did not meet the basic requirements of a nutrient intervention study, including vitamin D-replete populations, too small sample sizes, and inconsistent intervention methods regarding dose and metabolites. Vitamin D deficiency (serum 25-hydroxyvitamin D [25(OH)D] < 50 nmol/L or 20 ng/ml) is associated with unfavorable skeletal outcomes, including fractures and bone loss. A 25(OH)D level of >50 nmol/L or 20 ng/ml is, therefore, the primary treatment goal, although some data suggest a benefit for a higher threshold. Severe vitamin D deficiency with a 25(OH)D concentration below <30 nmol/L (or 12 ng/ml) dramatically increases the risk of excess mortality, infections, and many other diseases, and should be avoided whenever possible. The data on a benefit for mortality and prevention of infections, at least in severely deficient individuals, appear convincing. Vitamin D is clearly not a panacea, and is most likely efficient only in deficiency. Given its rare side effects and its relatively wide safety margin, it may be an important, inexpensive, and safe adjuvant therapy for many diseases, but future large and well-designed studies should evaluate this further. A worldwide public health intervention that includes vitamin D supplementation in certain risk groups, and systematic vitamin D food fortification to avoid severe vitamin D deficiency, would appear to be important. In this narrative review, the current international literature on vitamin D deficiency, its relevance, and therapeutic options is discussed.

Vitamin D levels in liver transplantation recipients and early postoperative outcomes: Prospective observational DLiverX study

BACKGROUND & AIMS

In critically ill patients with liver disease, vitamin D deficiency is associated with higher disease severity, increased frequency of infections, and worse outcomes. This study sought to describe the trend of vitamin D in orthotopic liver transplantation (OLT) recipients and its association with outcomes.

METHODS

Prospective observational study of 67 consecutive OLT recipients enrolled between September, 2016 and August, 2017 at IRCCS-ISMETT, Palermo (Italy). Trend of vitamin D levels and potential factors influencing it levels were evaluated through a generalized linear mixed regression model.

RESULTS

Sixty-four (95.5%) recipients were vitamin D deficient (<20 ng/ml), with a median value of 8.8 ng/ml [6.2-12.9], and forty-seven of these (70.1%) showed severe deficiency (<12 ng/ml) at baseline, 7.9 ng/ml [5.4-8.9]. The baseline vitamin D showed an inverse correlation with liver disease severity: Child-Pugh, MELD score, bilirubin, INR, and organ failure (p < 0.01) at baseline. Vitamin D increased on postoperative day (POD) 28 compared with POD1: +4.5 ng/ml, C.I. 95% 3.6-5.3 ng/ml, p < 0.01. Lower baseline vitamin D, donor age, transfusion of fresh frozen plasma (negative impact, all p < 0.05), and intra-operative bypass (positive impact at POD 28, p < 0.01) were associated with variation of vitamin D levels after transplantation. Incomplete graft recovery was associated with lower vitamin D on POD28: 8.2 ± 4.4 versus 13.8 ± 9.4 ng/ml, p < 0.01; the odds ratio (OR) was 0.84; CI 95% 0.73-0.97, p = 0.014. The OR for infections within POD 28 was inversely associated with baseline vitamin D: 0.87; CI 95% 0.79-0.98, p = 0.02, and with vitamin D level at baseline <12 ng/ml: OR 6.44; CI 95% 1.66-24.94; p < 0.01.

CONCLUSIONS

Preoperative Vitamin D is correlated with disease severity, and was highly associated with invasive infection in the first 28 PODs. After OLT, the value on POD 28 had a strong association with graft function.

The Role of Vitamin D in Combination Treatment for Patients With Rheumatoid Arthritis

Background: The aim of this study is to evaluate the clinical efficacy of vitamin D (VitD) supplementation in terms of response to treatment and improvement of disease activity in rheumatoid arthritis (RA). Methods: This study analyzed 1180 RA patients' records treated at Mianyang Central Hospital from February 2015 to July 2019. The patients were allocated into VitD group and control group based on their medical regimens. The outcome measures were primary efficacy, defined as treatment response-based EULAR response criteria in RA, and secondary efficacy, defined as improvement in disease activity indicators. Safety was evaluated according to the incidence of all-cause infections. Results: At month 6, the primary efficacy revealed that there were 22.8% good responders and 19.0% moderate responders in the VitD group, and 22.3% good responders and 22.3% moderate responders in the control group; there were no differences between the two groups (p = 0.754). The similar primary efficacy outcomes were observed at months 3, 12, and >12. The secondary efficacy indicated that there were no differences in most indexes between the two groups at months 1, 3, 6, 12, and >12. The subgroups (based on baseline DAS28 (CRP), glucocorticoids use and disease duration) analysis results suggested that VitD group didn't have the advantage for treating RA. The incidence of infections was similar in the two groups. Conclusion: VitD supplementation did not provide additional benefit for anti-rheumatic treatment. These data supported the need for prospective, randomized, controlled trials to evaluate the role of VitD supplementation in treating RA.

Vitamin D reduces autophagy by regulating NF-κB resistance to Aspergillus fumigatus infection

Vitamin D is one of the indispensable nutrients of human body. When vitamin D is deficient, it can cause a series of related diseases, such as respiratory tract infection. The regulatory role of vitamin D in inflammatory immune response and defense has attracted more and more attention. However, few studies have shown that vitamin D regulates inflammation and autophagy in Aspergillus fumigatus infected lungs. In this study, we will explain the mechanism of vitamin D regulating inflammation and autophagy in Aspergillus fumigatus infected lungs.

METHODS

Different concentrations of Aspergillus fumigatus spores were injected into mice with deficien diets (VitD-) or sufficient vitamin D (VitD + ) , and the survival rates were recorded. Then, the weight changes of rats were measured every other time. At the same time, a gauze was used to filter the lapped lung tissue to get the pulmonary spores and measured the amount of the spores. The mice with the same concentration of Aspergillus fumigatus infected were cut off and the lung tissue for pathological examination in the deficien diets (VitD-) group or sufficient vitamin D (VitD + ) group. Moreover, the expression of inflammation related factors TNF-α, IL-1β, IL-6 in lung was measured by immunohistochemical method. The expression of TNF-α, IL-1β, IL-6 in the serum of vitamin D deficiency and sufficient mice were measured by ELISA. In vitro, we obtained macrophages from healthy mice and mixed cultures of Aspergillus fumigatus spores and lung macrophages in medium with or without vitamin D. After the cells were infected with Aspergillus fumigatus spores, the expressions of NF-κB and IL-8 were detected by RT-PCR and Western blot. The RAW264.7 cells transfected with GFP-LC3BII were mixed with Aspergillus fumigatus spores, and the expression of cell fluorescence was observed by the fluorescence microscope with or without chloroquine and rapamycin , and the autophagy flow of the cells was measured by Western blot. In the RAW264.7 cells, Lentivirus transfection and SiRNA technologies were used to enhance or reduce the expression of the NF-κB gene (siNF-κB) for investgating the influence of high or low expression of NF-κB in the autophagic flow of vitamin D + or vitamin D-treated RAW264.7 cells.

RESULTS

The survival rate of vitamin D deficient mice infected Aspergillus fumigatus was significantly lower than that of vitamin D sufficient mice, while the number of spores, spore activity, pathological changes of lungs and inflammation in the lungs of vitamin D deficient mice were more severe than that of vitamin D sufficient mice. In vitro cell experiments, when cell was stimulated with vitamin D, the expressions of NF-κB and IL-8 in cells were lower. The autophagic flux and TNF-α, IL-1β, IL-6 and LC3BII in vitamin D group were significantly lower than those in vitamin D deficiency group.

CONCLUSIONS

Vitamin D deficiency can aggravate the inflammatory damage in the lungs of Aspergillus fumigatus. When the body is sufficient in vitamin D, if the lungs infect Aspergillus fumigatus spores, the body may resist the infection of Aspergillus fumigatus by reducing the expression of NF-κB, inflammatory factors and autophagy.