European Nicotinamide Diabetes Intervention Trial (ENDIT): a randomised controlled trial of intervention before the onset of type 1 diabetes

Intake of B vitamins and the risk of developing islet autoimmunity and type 1 diabetes in the TEDDY study

PURPOSE

The aim was to study the association between dietary intake of B vitamins in childhood and the risk of islet autoimmunity (IA) and progression to type 1 diabetes (T1D) by the age of 10 years.

METHODS

We followed 8500 T1D-susceptible children born in the U.S., Finland, Sweden, and Germany in 2004 -2010 from the Environmental Determinants of Diabetes in the Young (TEDDY) study, which is a prospective observational birth cohort. Dietary intake of seven B vitamins was calculated from foods and dietary supplements based on 24-h recall at 3 months and 3-day food records collected regularly from 6 months to 10 years of age. Cox proportional hazard models were adjusted for energy, HLA-genotype, first-degree relative with T1D, sex, and country.

RESULTS

A total of 778 (9.2) children developed at least one autoantibody (any IA), and 335 (3.9%) developed multiple autoantibodies. 280 (3.3%) children had IAA and 319 (3.8%) GADA as the first autoantibody. 344 (44%) children with IA progressed to T1D. We observed that higher intake of niacin was associated with a decreased risk of developing multiple autoantibodies (HR 0.95; 95% CI 0.92, 0.98) per 1 mg/1000 kcal in niacin intake. Higher intake of pyridoxine (HR 0.66; 95% CI 0.46, 0.96) and vitamin B12 (HR 0.87; 95% CI 0.77, 0.97) was associated with a decreased risk of IAA-first autoimmunity. Higher intake of riboflavin (HR 1.38; 95% CI 1.05, 1.80) was associated with an increased risk of GADA-first autoimmunity. There were no associations between any of the B vitamins and the outcomes "any IA" and progression from IA to T1D.  CONCLUSION: In this multinational, prospective birth cohort of children with genetic susceptibility to T1D, we observed some direct and inverse associations between different B vitamins and risk of IA.

Nicotinamide in Combination with EGFR-TKIs for the Treatment of Stage IV Lung Adenocarcinoma with EGFR Mutations: A Randomized Double-Blind (Phase IIb) Trial

PURPOSE

RUNX3 is a tumor suppressor gene, which is inactivated in approximately 70% of lung adenocarcinomas. Nicotinamide, a sirtuin inhibitor, has demonstrated potential in re-activating epigenetically silenced RUNX3 in cancer cells. This study assessed the therapeutic benefits of combining nicotinamide with first-generation EGFR-tyrosine kinase inhibitors (TKI) for patients with stage IV lung cancer carrying EGFR mutations.

PATIENTS AND METHODS

We assessed the impact of nicotinamide on carcinogen-induced lung adenocarcinomas in mice and observed that nicotinamide increased RUNX3 levels and inhibited lung cancer growth. Subsequently, 110 consecutive patients with stage IV lung cancer who had EGFR mutations were recruited: 70 females (63.6%) and 84 never-smokers (76.4%). The patients were randomly assigned to receive either nicotinamide (1 g/day, n = 55) or placebo (n = 55). The primary and secondary endpoints were progression-free survival (PFS) and overall survival (OS), respectively.

RESULTS

After a median follow-up of 54.3 months, the nicotinamide group exhibited a median PFS of 12.7 months [95% confidence interval (CI), 10.4-18.3], while the placebo group had a PFS of 10.9 months (9.0-13.2; P = 0.2). The median OS was similar in the two groups (31.0 months with nicotinamide vs. 29.4 months with placebo; P = 0.2). Notably, subgroup analyses revealed a significant reduction in mortality risk for females (P = 0.01) and never-smokers (P = 0.03) treated with nicotinamide.

CONCLUSIONS

The addition of nicotinamide with EGFR-TKIs demonstrated potential improvements in PFS and OS, with notable survival benefits for female patients and those who had never smoked (ClinicalTrials.gov Identifier: NCT02416739).

Islet autoantibodies as precision diagnostic tools to characterize heterogeneity in type 1 diabetes: a systematic review

BACKGROUND

Islet autoantibodies form the foundation for type 1 diabetes (T1D) diagnosis and staging, but heterogeneity exists in T1D development and presentation. We hypothesized that autoantibodies can identify heterogeneity before, at, and after T1D diagnosis, and in response to disease-modifying therapies.

METHODS

We systematically reviewed PubMed and EMBASE databases (6/14/2022) assessing 10 years of original research examining relationships between autoantibodies and heterogeneity before, at, after diagnosis, and in response to disease-modifying therapies in individuals at-risk or within 1 year of T1D diagnosis. A critical appraisal checklist tool for cohort studies was modified and used for risk of bias assessment.

RESULTS

Here we show that 152 studies that met extraction criteria most commonly characterized heterogeneity before diagnosis (91/152). Autoantibody type/target was most frequently examined, followed by autoantibody number. Recurring themes included correlations of autoantibody number, type, and titers with progression, differing phenotypes based on order of autoantibody seroconversion, and interactions with age and genetics. Only 44% specifically described autoantibody assay standardization program participation.

CONCLUSIONS

Current evidence most strongly supports the application of autoantibody features to more precisely define T1D before diagnosis. Our findings support continued use of pre-clinical staging paradigms based on autoantibody number and suggest that additional autoantibody features, particularly in relation to age and genetic risk, could offer more precise stratification. To improve reproducibility and applicability of autoantibody-based precision medicine in T1D, we propose a methods checklist for islet autoantibody-based manuscripts which includes use of precision medicine MeSH terms and participation in autoantibody standardization workshops.

Patients' willingness to accept adverse event and cost tradeoffs from oral nicotinamide for reduced risk of non-melanoma skin cancer

BACKGROUND

Non-immunosuppressed patients with a history of multiple non-melanoma skin cancers (NMSCs) taking oral nicotinamide supplementation experienced a 23% decrease in annual NMSC risk in a randomized clinical trial. Patient preferences for risks and costs associated with nicotinamide are unknown.

OBJECTIVES

To understand how patients prioritize NMSC reduction, infection risk, and cost.

METHODS

A sample of adults with history of ≥2 NMSC within the past five years undergoing Mohs procedure completed a discrete-choice experiment comprising two hypothetical treatments-characterized by varying reductions in NMSC incidence, increased severe infection risk, and cost-and no treatment. The data were analyzed with random-parameters logit models.

RESULTS

A total of 203 subjects (mean age 71.5 years, 65.5% males) participated. For a 23% annual reduction in NMSC incidence, a 26% [95% CI: 8%-45%] annual increase in severe infection risk and $8 [95% CI: $2-14] monthly cost was acceptable. Outcomes across analyzed subgroups (before vs. during COVID pandemic, site of interview, less vs. more prior NMSCs) were similar.

CONCLUSIONS

Patients were unwilling to accept high severe infection risks to obtain the reduction in NMSC incidence observed in a nicotinamide trial, suggesting that routinely recommending nicotinamide may run counter to some patients' preferences.

NAD+ precursor nutritional supplements sensitize the brain to future ischemic events

Nicotinamide adenine dinucleotide (NAD+) is a redox cofactor critical for oxidative phosphorylation. Nicotinamide (NAM) and nicotinamide riboside (NR) are NAD+ precursors widely used as nutritional supplements to augment oxidative phosphorylation. Indeed, NAD+ precursors have been reported to improve outcomes in ischemic stroke when administered as a rescue therapy after stroke onset. However, we have also reported that enhanced reliance on oxidative phosphorylation before ischemia onset might worsen outcomes. To address the paradox, we examined how NAD+ precursors modulate the outcome of middle cerebral artery occlusion in mice, when administered either 20 minutes after reperfusion or daily for three days before ischemia onset. A single post-ischemic dose of NAM or NR indeed improved tissue and neurologic outcomes examined at 72 hours. In contrast, pre-ischemic treatment for three days enlarged the infarcts and worsened neurological deficits. As a possible explanation for the diametric outcomes, a single dose of NAM or NR augmented tissue AMPK, PGC1α, SIRT1, and ATP in both naïve and ischemic brains, while the multiple-dose paradigm failed to do so. Our data suggest that NAD+ precursor supplements may sensitize the brain to subsequent ischemic events, despite their neuroprotective effect when administered after ischemia onset.

The Safety and Antiaging Effects of Nicotinamide Mononucleotide in Human Clinical Trials: an Update

The importance of nicotinamide adenine dinucleotide (NAD+) in human physiology is well recognized. As the NAD+ concentration in human skin, blood, liver, muscle, and brain are thought to decrease with age, finding ways to increase NAD+ status could possibly influence the aging process and associated metabolic sequelae. Nicotinamide mononucleotide (NMN) is a precursor for NAD+ biosynthesis, and in vitro/in vivo studies have demonstrated that NMN supplementation increases NAD+ concentration and could mitigate aging-related disorders such as oxidative stress, DNA damage, neurodegeneration, and inflammatory responses. The promotion of NMN as an antiaging health supplement has gained popularity due to such findings; however, since most studies evaluating the effects of NMN have been conducted in cell or animal models, a concern remains regarding the safety and physiological effects of NMN supplementation in the human population. Nonetheless, a dozen human clinical trials with NMN supplementation are currently underway. This review summarizes the current progress of these trials and NMN/NAD+ biology to clarify the potential effects of NMN supplementation and to shed light on future study directions.

Disease-modifying therapies and features linked to treatment response in type 1 diabetes prevention: a systematic review

BACKGROUND

Type 1 diabetes (T1D) results from immune-mediated destruction of insulin-producing beta cells. Prevention efforts have focused on immune modulation and supporting beta cell health before or around diagnosis; however, heterogeneity in disease progression and therapy response has limited translation to clinical practice, highlighting the need for precision medicine approaches to T1D disease modification.

METHODS

To understand the state of knowledge in this area, we performed a systematic review of randomized-controlled trials with ≥50 participants cataloged in PubMed or Embase from the past 25 years testing T1D disease-modifying therapies and/or identifying features linked to treatment response, analyzing bias using a Cochrane-risk-of-bias instrument.

RESULTS

We identify and summarize 75 manuscripts, 15 describing 11 prevention trials for individuals with increased risk for T1D, and 60 describing treatments aimed at preventing beta cell loss at disease onset. Seventeen interventions, mostly immunotherapies, show benefit compared to placebo (only two prior to T1D onset). Fifty-seven studies employ precision analyses to assess features linked to treatment response. Age, beta cell function measures, and immune phenotypes are most frequently tested. However, analyses are typically not prespecified, with inconsistent methods of reporting, and tend to report positive findings.

CONCLUSIONS

While the quality of prevention and intervention trials is overall high, the low quality of precision analyses makes it difficult to draw meaningful conclusions that inform clinical practice. To facilitate precision medicine approaches to T1D prevention, considerations for future precision studies include the incorporation of uniform outcome measures, reproducible biomarkers, and prespecified, fully powered precision analyses into future trial design.

The use of Nicotinamide and Nicotinamide riboside as an adjunct therapy in the treatment of glaucoma

Glaucoma is an optic neuropathy characterized by death of retinal ganglion cells (RGCs), which leads to progressive visual field loss and may result in blindness. Currently, the only available treatment to avoid or delay progression in glaucoma patients is to decrease intraocular pressure (IOP). However, despite adequate IOP control, approximately 25% of the patients continue to progress. To delay or prevent optic nerve damage in glaucoma, two forms of vitamin B3, nicotinamide (NAM) and nicotinamide riboside (NR) are emerging as viable adjuvant therapies. These compounds are nicotinamide adenine dinucleotide (NAD) precursors. NAD is essential for proper cell functioning and is involved in several metabolic activities, including protection against reactive oxygen species, contribution to the performance of various enzymes, and maintenance of mitochondrial function. Due to its beneficial effects and to the evidence of the reduction of NAD bioavailability with aging, researchers are seeking ways to replenish the cellular NAD pool, by administrating its precursors (NAM and NR), believing that it will reduce the RGC vulnerability to external stressors, such as increased IOP. This article attempts to analyze the current knowledge regarding the use of NAM and NR for the prevention and/or treatment of glaucoma.

Lactate: A Theranostic Biomarker for Metabolic Psychiatry?

Alterations in neurometabolism and mitochondria are implicated in the pathophysiology of psychiatric conditions such as mood disorders and schizophrenia. Thus, developing objective biomarkers related to brain mitochondrial function is crucial for the development of interventions, such as central nervous system penetrating agents that target brain health. Lactate, a major circulatory fuel source that can be produced and utilized by the brain and body, is presented as a theranostic biomarker for neurometabolic dysfunction in psychiatric conditions. This concept is based on three key properties of lactate that make it an intriguing metabolic intermediate with implications for this field: Firstly, the lactate response to various stimuli, including physiological or psychological stress, represents a quantifiable and dynamic marker that reflects metabolic and mitochondrial health. Second, lactate concentration in the brain is tightly regulated according to the sleep-wake cycle, the dysregulation of which is implicated in both metabolic and mood disorders. Third, lactate universally integrates arousal behaviours, pH, cellular metabolism, redox states, oxidative stress, and inflammation, and can signal and encode this information via intra- and extracellular pathways in the brain. In this review, we expand on the above properties of lactate and discuss the methodological developments and rationale for the use of functional magnetic resonance spectroscopy for in vivo monitoring of brain lactate. We conclude that accurate and dynamic assessment of brain lactate responses might contribute to the development of novel and personalized therapies that improve mitochondrial health in psychiatric disorders and other conditions associated with neurometabolic dysfunction.

Nicotinamide mononucleotide (NMN) intake increases plasma NMN and insulin levels in healthy subjects

INTRODUCTION

Nicotinamide adenine dinucleotide (NAD⁺) is a coenzyme of the NAD⁺-dependent protein deacetylase sirtuin-1 (SIRT1). An increase in NAD⁺ concentration induces SIRT1 activation that results in various health benefits. Since nicotinamide mononucleotide (NMN) is a precursor of NAD⁺, NMN ingestion is expected to have multiple health benefits such as alleviation of aging, lifestyle-related and neurodegenerative diseases, through the activation of SIRT1. In this study, we aimed to determine the effects of daily NMN ingestion on plasma levels of NMN and NAD⁺.

METHODS

Healthy volunteers received 250 mg of NMN once a day in the morning (n = 11) for 12 weeks, and the plasma concentrations of NMN and NAD⁺ were measured monthly. Physiological and laboratory tests were performed within 2 h after lunch (at 2 pm) before and during NMN administration.

RESULTS

Oral administration of NMN increased the plasma concentrations of NMN and NAD⁺, and the postprandial serum insulin levels. The elevation levels of NMN and insulin varied widely among individuals. No adverse symptoms were observed in the participants.

CONCLUSIONS

Oral administration of NMN elevates plasma levels of NMN and NAD⁺, and postprandial serum insulin levels.

Type 1 diabetes

Type 1 diabetes is a chronic disease caused by autoimmune destruction of pancreatic β cells. Individuals with type 1 diabetes are reliant on insulin for survival. Despite enhanced knowledge related to the pathophysiology of the disease, including interactions between genetic, immune, and environmental contributions, and major strides in treatment and management, disease burden remains high. Studies aimed at blocking the immune attack on β cells in people at risk or individuals with very early onset type 1 diabetes show promise in preserving endogenous insulin production. This Seminar will review the field of type 1 diabetes, highlighting recent progress within the past 5 years, challenges to clinical care, and future directions in research, including strategies to prevent, manage, and cure the disease.

Type 1 Diabetes Prevention: a systematic review of studies testing disease-modifying therapies and features linked to treatment response

Background

Type 1 diabetes (T1D) results from immune-mediated destruction of insulin-producing beta cells. Efforts to prevent T1D have focused on modulating immune responses and supporting beta cell health; however, heterogeneity in disease progression and responses to therapies have made these efforts difficult to translate to clinical practice, highlighting the need for precision medicine approaches to T1D prevention.

Methods

To understand the current state of knowledge regarding precision approaches to T1D prevention, we performed a systematic review of randomized-controlled trials from the past 25 years testing disease-modifying therapies in T1D and/or identifying features linked to treatment response, analyzing bias using a Cochrane-risk-of-bias instrument.

Results

We identified 75 manuscripts, 15 describing 11 prevention trials for individuals with increased risk for T1D, and 60 describing treatments aimed at preventing beta cell loss in individuals at disease onset. Seventeen agents tested, mostly immunotherapies, showed benefit compared to placebo (only two prior to T1D onset). Fifty-seven studies employed precision analyses to assess features linked to treatment response. Age, measures of beta cell function and immune phenotypes were most frequently tested. However, analyses were typically not prespecified, with inconsistent methods reporting, and tended to report positive findings.

Conclusions

While the quality of prevention and intervention trials was overall high, low quality of precision analyses made it difficult to draw meaningful conclusions that inform clinical practice. Thus, prespecified precision analyses should be incorporated into the design of future studies and reported in full to facilitate precision medicine approaches to T1D prevention.

Plain Language Summary

Type 1 diabetes (T1D) results from the destruction of insulin-producing cells in the pancreas, necessitating lifelong insulin dependence. T1D prevention remains an elusive goal, largely due to immense variability in disease progression. Agents tested to date in clinical trials work in a subset of individuals, highlighting the need for precision medicine approaches to prevention. We systematically reviewed clinical trials of disease-modifying therapy in T1D. While age, measures of beta cell function, and immune phenotypes were most commonly identified as factors that influenced treatment response, the overall quality of these studies was low. This review reveals an important need to proactively design clinical trials with well-defined analyses to ensure that results can be interpreted and applied to clinical practice.

Oral nicotinamide for non-melanoma skin cancers: A review

There has been much interest in the role of oral nicotinamide supplementation in reducing the incidence of non-melanoma skin cancers. This article reviews the hypothesised mechanisms of action of nicotinamide, and the available literature outlining its role for this purpose. There have been five randomised controlled trials (RCT), one histopathological study and two case series exploring the effect of oral nicotinamide supplementation on UV-induced immunosuppression of the skin, and incidence of actinic keratoses and non-melanoma skin cancers (NMSC). The largest RCT received criticism of the statistical analyses used, but the critics still acknowledged a likely benefit of treatment with oral nicotinamide in reducing the incidence of NMSC. Nicotinamide has a favourable safety profile. Current evidence is not definitive that oral nicotinamide supplementation reduces the incidence of NMSC, but it constitutes a low-risk management option that may be particularly relevant for high-risk individuals, and should be discussed as an option for these patients.

A perspective on treating type 1 diabetes mellitus before insulin is needed

Type 1 diabetes mellitus (T1DM) is a progressive autoimmune disease that starts long before a clinical diagnosis is made. The American Diabetes Association recognizes three stages: stage 1 (normoglycaemic and positive for autoantibodies to β-cell antigens); stage 2 (asymptomatic with dysglycaemia); and stage 3, which is defined by glucose levels consistent with the definition of diabetes mellitus. This Perspective focuses on the management of the proportion of individuals with early stage 3 T1DM who do not immediately require insulin; a stage we propose should be termed stage 3a. To date, this period of non-insulin-dependent T1DM has been largely unrecognized. Importantly, it represents a window of opportunity for intervention, as remaining at this stage might delay the need for insulin by months or years. Extending the insulin-free period and/or avoiding unnecessary insulin therapy are important goals, as there is no risk of hypoglycaemia during this period and the adherence burden on patients of glycaemic monitoring and daily adjustments for diet and exercise is substantially reduced. Recognizing the pressing need for guidance on adequate management of children and adults with stage 3a T1DM, we present our perspective on the subject, which needs to be tested in formal and adequately powered clinical trials.

Preventing type 1 diabetes development and preserving beta-cell function

PURPOSE OF REVIEW

Type 1 diabetes (T1D) is the most common chronic disease of childhood presenting a significant burden, both in terms of day-to-day medical management and lifelong care. Studies aligned with diverse strategies to prevent or modify the course of T1D are reviewed.

RECENT FINDINGS

The diagnosis of T1D precedes the classic clinical presentation when insulin dependence develops. With an increased understanding of the pathophysiology of the autoimmune process leading to T1D, treatment strategies to prevent the development of autoimmunity and/or modify the immune response have been trialed in persons at risk for developing the disease. Interventions prior to insulin dependence or very early after clinical diagnosis show some promise both in preventing disease onset and prolonging beta-cell insulin production.

SUMMARY

Significant progress has been made in the treatment of T1D. However, suboptimal glycemic control remains a challenge impacting overall health and quality of life for patients with this chronic disease. Although physicians and basic sciences investigators continue to pursue the prevention of the autoimmune process, the advent of disease-modifying agents is a promising strategy. Further studies are needed to ensure that insulin preservation can be achieved longer term.

Exercise training and NR supplementation to improve muscle mass and fitness in adolescent and young adult hematopoietic cell transplant survivors: a randomized controlled trial {1}

Background

Advances in hematopoietic cell transplantation (HCT) have led to marked improvements in survival. However, adolescents and young adults (AYAs) who undergo HCT are at high risk of developing sarcopenia (loss of skeletal muscle mass) due to the impact of HCT-related exposures on the developing musculoskeletal system. HCT survivors who have sarcopenia also have excess lifetime risk of non-relapse mortality. Therefore, interventions that increase skeletal muscle mass, metabolism, strength, and function are needed to improve health in AYA HCT survivors. Skeletal muscle is highly reliant on mitochondrial energy production, as reflected by oxidative phosphorylation (OXPHOS) capacity. Exercise is one approach to target skeletal muscle mitochondrial OXPHOS, and in turn improve muscle function and strength. Another approach is to use “exercise enhancers”, such as nicotinamide riboside (NR), a safe and well-tolerated precursor of nicotinamide adenine dinucleotide (NAD⁺), a cofactor that in turn impacts muscle energy production. Interventions combining exercise with exercise enhancers like NR hold promise, but have not yet been rigorously tested in AYA HCT survivors.

Methods/design

We will perform a randomized controlled trial testing 16 weeks of in-home aerobic and resistance exercise and NR in AYA HCT survivors, with a primary outcome of muscle strength via dynamometry and a key secondary outcome of cardiovascular fitness via cardiopulmonary exercise testing. We will also test the effects of these interventions on i) muscle mass via dual energy x-ray absorptiometry; ii) muscle mitochondrial OXPHOS via an innovative non-invasive MRI-based technique, and iii) circulating correlates of NAD⁺ metabolism via metabolomics. Eighty AYAs (ages 15-30y) will be recruited 6–24 months post-HCT and randomized to 1 of 4 arms: exercise + NR, exercise alone, NR alone, or control. Outcomes will be collected at baseline and after the 16-week intervention.

Discussion

We expect that exercise with NR will produce larger changes than exercise alone in key outcomes, and that changes will be mediated by increases in muscle OXPHOS. We will apply the insights gained from this trial to develop individualized, evidence-supported precision initiatives that will reduce chronic disease burden in high-risk cancer survivors.

Trial registration

ClinicalTrials.gov, NCT05194397. Registered January 18, 2022, https://clinicaltrials.gov/ct2/show/NCT05194397 {2a}.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09845-1.

A Multicentre, Randomised, Double Blind, Parallel Design, Placebo Controlled Study to Evaluate the Efficacy and Safety of Uthever (NMN Supplement), an Orally Administered Supplementation in Middle Aged and Older Adults

Objective: The purpose of the study was to evaluate the anti-aging effect of NMN and its safety in a double-blind, parallel, randomised controlled clinical trial.

Methods: The study was carried out on 66 healthy subjects between the ages of 40 and65 years, instructed to take two capsules (each containing 150 mg. of NMN or starch powder) once a day after breakfast for 60 days.

Results: At day 30, NAD⁺/NADH levels in the serum showed a noteworthy increase, i.e., by 11.3%, whereas the placebo group had shown no change at all. At the end of the study, i.e., day 60, the NAD⁺/NADH levels were increased further by 38% compared to baseline, against a mere 14.3% in the placebo group. In the case of SF 36, at day 60, the Uthever group showed a rise of 6.5%, whereas the placebo group was merely raised by 3.4%. At the end of the study, the mean HOMA IR Index showed a rise of 0.6% among the Uthever group and 30.6% among the Placebo group from baseline.

Conclusion: The rise in the levels of NAD⁺/NADH at day 30 and day 60 illustrated the potential of Uthever to raise the levels of NAD⁺ in the cells, which is linked to higher energy levels and an anti-aging effect. Increased sensitivity to insulin has also been linked to anti-aging. There was no noteworthy change in HOMA score, in the Uthever group whereas there was a noteworthy rise in the placebo group, demonstrating the anti-aging effect of Uthever as in its absence, the parameters worsened.

Clinical Trial Registration: (clinicaltrials.gov), identifier (NCT04228640 NMN).

Effect of Nicotinamide in Skin Cancer and Actinic Keratoses Chemoprophylaxis, and Adverse Effects Related to Nicotinamide: A Systematic Review and Meta-Analysis

BACKGROUND

Oral nicotinamide is recommended in individuals with a field of cancerization or with ≥1 previous cutaneous squamous cell carcinoma (cSCC).

OBJECTIVE

To evaluate the effect of nicotinamide in prevention of skin cancers.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials to evaluate the effect of nicotinamide. We used Medline, EMBASE, CENTRAL, and Web of Science databases from their inception to October 2020 to search the following concepts: "nicotinamide"; "randomized controlled trial" (validated filters). Two independent reviewers screened titles and abstracts for intervention and study design before searching full texts for eligibility criteria. To be eligible, ≥1 outcome had to be covered. We used a standardized collection grid to complete data extraction in duplicate. The primary outcome was skin cancers (all types). Secondary outcomes were basal cell carcinomas (BCCs); cSCCs; actinic keratoses; melanomas; digestive, cutaneous, and biochemical adverse effects (AEs). Subgroup analyses were planned a priori.

RESULTS

We screened 4730 citations and found 29 trials (3039 patients) meeting inclusion criteria. Nicotinamide was associated with a significant reduction in skin cancers compared to control (rate ratio 0.50 (95% CI, 0.29-0.85; I 2 = 64%; 552 patients; 5 trials); moderate strength of the evidence). Heterogeneity was explained by risk of bias. Nicotinamide was associated with a significant reduction in BCCs and cSCCs, and increased risk of digestive AEs.

CONCLUSION

Oral nicotinamide should be considered in healthy patients or organ transplant recipients with history of skin cancer (GRADE: weak recommendation; moderate-quality evidence), in particular of BCC and cSCC.

Neuroprotective Effects of Nicotinamide (Vitamin B3) on Neurodegeneration in Diabetic Rat Retinas

The loss of inner retinal neurons is an initial event in diabetic retinopathy. In diabetic retinas, oxidative stress is increased, which could lead to increased oxidative DNA damage. Nicotinamide is a precursor to nicotinamide adenine dinucleotide, which contributes to the DNA damage response. We investigated whether nicotinamide plays a neuroprotective role in diabetic retinal neurodegeneration in terms of DNA repair. Male Sprague Dawley rats with streptozotocin-induced diabetes were orally administered nicotinamide (500 mg/kg/day) for 4 or 12 weeks. Oxidative stress exhibited by dihydroethidium was upregulated at 4 and 12 weeks after onset of diabetes, and nicotinamide treatment reduced oxidative stress at 4 weeks after induction of diabetes. Oxidative DNA damage measured by 8-hydroxy-2′-deoxyguanosine (8-OHdG) increased at 4 and 12 weeks after induction of diabetes and decreased following nicotinamide treatment. The elevated expression of glial fibrillary acidic protein (GFAP) induced by diabetes was attenuated by nicotinamide treatment. In Western blot analysis, the increased expression of cleaved PARP-1 in diabetes was attenuated by nicotinamide treatment at 12 weeks after induction of diabetes. The diabetes-induced apoptosis of inner retinal cells detected by the TUNEL assay was reduced by nicotinamide treatment. In conclusion, nicotinamide attenuated retinal neurodegeneration in diabetes, probably by reducing oxidative DNA damage and supporting DNA repair.

Effect of intensive education on stroke prevention and management ability of community doctors: a cross-sectional study

BACKGROUND

Prevention and treatment of stroke are extremely important to reduce the incidence of stroke-related disability and the associated death. This study aimed to investigate the current ability of community doctors in stroke management in the Jinjiang district of Chengdu, China, and the effect of intensive education on stroke prevention and management ability of these doctors.

METHODS

A self-designed questionnaire was used to investigate the current status of stroke management by community doctors in the Jinjiang district. Subsequently, a series of intensive stroke management education courses for community doctors was designed according to the relevant guidelines for cerebrovascular accident prevention and treatment in China. All community doctors were trained, and their ability to treat and prevent stroke was reassessed using the self-designed questionnaire.

RESULTS

Of the 450 questionnaires issued, 370 (82.2%) and 389 (86.4%) community doctors were enrolled before and after intensive education, respectively. The results showed that only 37.8% of the community doctors in the Jinjiang district knew the guidelines for the prevention and treatment of cerebrovascular diseases, and only 45.9% thought they had stroke management ability. The stroke management ability of community doctors improved after intensive education (p < 0.05), including pre-hospital identification and management of stroke, and management of its risk factors.

CONCLUSIONS

The capacity of community doctors in the Jinjiang district of Chengdu is far from meeting the requirements of stroke prevention and treatment. However, the stroke management ability of the community doctors was greatly improved by promoting intensive education.

Immunotherapy for type 1 diabetes

INTRODUCTION

Despite advances in technology including the development of more sophisticated methods of monitoring blood glucose and delivering insulin, many individuals with type 1 diabetes continue to experience significant challenges in optimizing glycaemic control. Alternative treatment approaches to insulin are required. Increasing efforts have focused on developing treatments aimed at targeting the underlying disease process to modulate the immune system, maximize beta cell function and enhance endogenous insulin production and action.

SOURCES OF DATA

Literature searches with keywords 'Type 1 diabetes and immunotherapy', publications relating to clinical trials of immunotherapy in type 1 diabetes.

AREAS OF AGREEMENT

Insulin therapy is insufficient to achieve optimal glycaemic control in many individuals with type 1 diabetes, and new treatment approaches are required. Studies have showed promising results for the use of immunotherapy as a means of delaying disease onset and progression.

AREAS OF CONTROVERSY

The optimal way of identifying individuals most likely to benefit from immunotherapies.

GROWING POINTS

A better understanding of the natural history of type 1 diabetes has made it possible to identify individuals who have developed autoimmunity but have not yet progressed to clinical diabetes, offering opportunities not only to develop treatments that delay disease progression, but prevent its development in the first place. A consensus on how to identify individuals who may benefit from immunotherapy to prevent disease onset is needed.

AREAS TIMELY FOR DEVELOPING RESEARCH

The development of optimal strategies for preventing and delaying progression of type 1 diabetes, and monitoring the response to immunointervention.

Pharmacology and Potential Implications of Nicotinamide Adenine Dinucleotide Precursors

Coenzyme I (nicotinamide adenine dinucleotide, NAD⁺/NADH) and coenzyme II (nicotinamide adenine dinucleotide phosphate, NADP^+/NADPH) are involved in various biological processes in mammalian cells. NAD⁺ is synthesised through the de novo and salvage pathways, whereas coenzyme II cannot be synthesised de novo. NAD⁺ is a precursor of coenzyme II. Although NAD⁺ is synthesised in sufficient amounts under normal conditions, shortage in its supply due to over consumption and its decreased synthesis has been observed with increasing age and under certain disease conditions. Several studies have proved that in a wide range of tissues, such as liver, skin, muscle, pancreas, and fat, the level of NAD⁺ decreases with age. However, in the brain tissue, the level of NADH gradually increases and that of NAD⁺ decreases in aged people. The ratio of NAD⁺/NADH indicates the cellular redox state. A decrease in this ratio affects the cellular anaerobic glycolysis and oxidative phosphorylation functions, which reduces the ability of cells to produce ATP. Therefore, increasing the exogenous NAD⁺ supply under certain disease conditions or in elderly people may be beneficial. Precursors of NAD⁺ have been extensively explored and have been reported to effectively increase NAD⁺ levels and possess a broad range of functions. In this review article, we discuss the pharmacokinetics and pharmacodynamics of NAD⁺ precursors.

Therapeutic Potential of Emerging NAD+-Increasing Strategies for Cardiovascular Diseases

Cardiovascular diseases are the leading cause of death worldwide. Aging and/or metabolic stress directly impact the cardiovascular system. Over the last few years, the contributions of altered nicotinamide adenine dinucleotide (NAD+) metabolism to aging and other pathological conditions closely related to cardiovascular diseases have been intensively investigated. NAD+ bioavailability decreases with age and cardiometabolic conditions in several mammalian tissues. Compelling data suggest that declining tissue NAD+ is commonly related to mitochondrial dysfunction and might be considered as a therapeutic target. Thus, NAD+ replenishment by either genetic or natural dietary NAD+-increasing strategies has been recently demonstrated to be effective for improving the pathophysiology of cardiac and vascular health in different experimental models, as well as human health, to a lesser extent. Here, we review and discuss recent experimental evidence illustrating that increasing NAD+ bioavailability, particularly by the use of natural NAD+ precursors, may offer hope for new therapeutic strategies to prevent and treat cardiovascular diseases.

NAD+ Metabolism in Cardiac Health, Aging, and Disease

Nicotinamide adenine dinucleotide (NAD⁺) is a central metabolite involved in energy and redox homeostasis as well as in DNA repair and protein deacetylation reactions. Pharmacological or genetic inhibition of NAD⁺-degrading enzymes, external supplementation of NAD⁺ precursors, and transgenic overexpression of NAD⁺-generating enzymes have wide positive effects on metabolic health and age-associated diseases. NAD⁺ pools tend to decline with normal aging, obesity, and hypertension, which are all major risk factors for cardiovascular disease, and NAD⁺ replenishment extends healthspan, avoids metabolic syndrome, and reduces blood pressure in preclinical models. In addition, experimental elevation of NAD⁺ improves atherosclerosis, ischemic, diabetic, arrhythmogenic, hypertrophic, or dilated cardiomyopathies, as well as different modalities of heart failure. Here, we critically discuss cardiomyocyte-specific circuitries of NAD⁺ metabolism, comparatively evaluate distinct NAD⁺ precursors for their preclinical efficacy, and raise outstanding questions on the optimal design of clinical trials in which NAD⁺ replenishment or supraphysiological NAD⁺ elevations are assessed for the prevention or treatment of major cardiac diseases. We surmise that patients with hitherto intractable cardiac diseases such as heart failure with preserved ejection fraction may profit from the administration of NAD⁺ precursors. The development of such NAD⁺-centered treatments will rely on technological and conceptual progress on the fine regulation of NAD⁺ metabolism.

Environmental Determinants of Type 1 Diabetes: From Association to Proving Causality

The rising incidence of type 1 diabetes (T1D) cannot be ascribed to genetics alone, and causative environmental triggers and drivers must also be contributing. The prospective TEDDY study has provided the greatest contributions in modern time, by addressing misconceptions and refining the search strategy for the future. This review outlines the evidence to date to support the pathways from association to causality, across all stages of T1D (seroconversion to beta cell failure). We focus on infections and vaccinations; infant growth and childhood obesity; the gut microbiome and the lifestyle factors which cultivate it. Of these, the environmental determinants which have the most supporting evidence are enterovirus infection, rapid weight gain in early life, and the microbiome. We provide an infographic illustrating the key environmental determinants in T1D and their likelihood of effect. The next steps are to investigate these environmental triggers, ideally though gold-standard randomised controlled trials and further prospective studies, to help explore public health prevention strategies.

SIRT1-dependent restoration of NAD+ homeostasis after increased extracellular NAD+ exposure

In the last several years, NAD+ supplementation has emerged as an innovative and safe therapeutic strategy for a wide spectrum of disorders, including diabetes and neuropathy. However, critical questions remain as to how NAD+ and its precursors are taken up by cells, as well as the effects of long-lasting intracellular NAD+ (iNAD+) increases. Here, we investigated the kinetics of iNAD+ levels in different cell types challenged with prolonged exposure to extracellular NAD+ (eNAD+). Surprisingly, we found that after the initial increase, iNAD+ contents decreased back to control levels (iNAD+ resetting). Focusing our attention on HeLa cells, we found that oxygen and ATP consumption occurred with similar temporal kinetics after eNAD+ exposure. Using [³H]NAD+ and [¹⁴C]NAD+, we determined that NAD+ resetting was not due to increased dinucleotide extrusion but rather due to reduced uptake of cleaved NAD+ products. Indeed, eNAD+ exposure reduced the expression of the ecto-5′-nucleotidase CD73, the nicotinamide adenine mononucleotide transporter solute carrier family 12 member 8, and the nicotinamide riboside kinase. Interestingly, silencing the NAD+-sensor enzyme sirtuin 1 prevented eNAD+-dependent transcriptional repression of ecto-5′-nucleotidase, solute carrier family 12 member 8, and nicotinamide riboside kinase, as well as iNAD+ resetting. Our findings provide the first evidence for a sirtuin 1–mediated homeostatic response aimed at maintaining physiological iNAD+ levels in conditions of excess eNAD+ availability. These data may be of relevance for therapies designed to support the NAD+ metabolome via extracellular supplementation of the dinucleotide or its precursors.

A Key to T1D Prevention: Screening and Monitoring Relatives as Part of Clinical Care

The 2019 report of a randomized, placebo-controlled clinical trial demonstrating that immune therapy can delay the onset of clinical type 1 diabetes (T1D) in antibody-positive relatives by a median of 2 years stands out as a landmark in the decades-long effort to prevent T1D. With this important step achieved, it is now time to consider what is needed to bring disease-modifying therapy for prevention or delay of T1D to clinical use from this point. Long considered a chicken and egg problem (why screen for T1D risk when we have no therapy, and how can we develop therapies without more screening), we now have the opportunity to break this impasse. The purpose of this article is to place this clinical trial result in context, highlighting key foundational studies leading to this accomplishment, addressing the current gaps, and suggesting that a key next step for prevention of T1D is to screen and monitor relatives for T1D risk in the context of clinical care.

Teplizumab improves and stabilizes beta cell function in antibody-positive high-risk individuals

We analyzed the effects of a single 14-day course of teplizumab treatment on metabolic function and immune cells among participants in a previously reported randomized controlled trial of nondiabetic relatives at high risk for type 1 diabetes (T1D). In an extended follow-up (923-day median) of a previous report of teplizumab treatment, we found that the median times to diagnosis were 59.6 and 27.1 months for teplizumab- and placebo-treated participants, respectively (HR = 0.457, P = 0.01). Fifty percent of teplizumab-treated but only 22% of the placebo-treated remained diabetes-free. Glucose tolerance, C-peptide area under the curve (AUC), and insulin secretory rates were calculated, and relationships to T cell subsets and function were analyzed. Teplizumab treatment improved beta cell function, reflected by average on-study C-peptide AUC (1.94 versus 1.72 pmol/ml; P = 0.006). Drug treatment reversed a decline in insulin secretion before enrollment, followed by stabilization of the declining C-peptide AUC seen with placebo treatment. Proinsulin:C-peptide ratios after drug treatment were similar between the treatment groups. The changes in C-peptide with teplizumab treatment were associated with increases in partially exhausted memory KLRG1+TIGIT+CD8+ T cells (r = 0.44, P = 0.014) that showed reduced secretion of IFNγ and TNFα. A single course of teplizumab had lasting effects on delay of T1D diagnosis and improved beta cell function in high-risk individuals. Changes in CD8+ T cell subsets indicated that partially exhausted effector cells were associated with clinical response. Thus, this trial showed improvement in metabolic responses and delay of diabetes with immune therapy.

Okamoto model for necrosis and its expansions, CD38-cyclic ADP-ribose signal system for intracellular Ca2+ mobilization and Reg (Regenerating gene protein)-Reg receptor system for cell regeneration

In pancreatic islet cell culture models and animal models, we studied the molecular mechanisms involved in the development of insulin-dependent diabetes. The diabetogenic agents, alloxan and streptozotocin, caused DNA strand breaks, which in turn activated poly(ADP-ribose) polymerase/synthetase (PARP) to deplete NAD+, thereby inhibiting islet β-cell functions such as proinsulin synthesis and ultimately leading to β-cell necrosis. Radical scavengers protected against the formation of DNA strand breaks and inhibition of proinsulin synthesis. Inhibitors of PARP prevented the NAD+ depletion, inhibition of proinsulin synthesis and β-cell death. These findings led to the proposed unifying concept for β-cell damage and its prevention (the Okamoto model). The model met one proof with PARP knockout animals and was further extended by the discovery of cyclic ADP-ribose as the second messenger for Ca2+ mobilization in glucose-induced insulin secretion and by the identification of Reg (Regenerating gene) for β-cell regeneration. Physiological and pathological events found in pancreatic β-cells have been observed in other cells and tissues.

NAD+-Increasing Strategies to Improve Cardiometabolic Health?

Depleted nicotinamide adenine dinucleotide (NAD+) is a common hallmark of metabolic disorders. Therefore, NAD+-increasing strategies have evolved as a potential therapeutic venue to combat cardiometabolic diseases. Several forms of vitamin B3, i.e., nicotinamide and nicotinamide mononucleotide, and especially nicotinamide riboside, have attracted most interest as potentially safe and efficacious candidates for NAD+ restoration. Herein, we dissected the characteristics of the latest clinical trials testing the therapeutic potential of different vitamin B3 molecules to improve cardiometabolic health, with a special focus on randomized, placebo-controlled clinical trials performed in the context of obesity or other pathologies, mainly linked to cardiovascular system and skeletal muscle functionality. The favorable outcomes via NAD+-increasing strategies found in the different studies were quite heterogeneous. NAD+-increasing interventions improved capacity to exercise, decreased blood pressure, increased the anti-inflammatory profile and insulin-stimulated glucose disposal, and reduced the fat-free mass. Except for the decreased blood pressure, the significant results did not include many hard clinical end points, such as decreases in weight, BMI, fasting glucose, or HbA1c percentage. However, the analyzed trials were short-term interventions. Overall, the accumulated clinical data can be interpreted as moderately promising. Additional and long-term studies will be needed to directly compare the doses and duration of treatments among different vitamin B3 regimes, as well as to define the type of patients, if any, that could benefit from these treatments. In this context, a major point of advancement in delineating future clinical trials would be to identify subjects with a recognized NAD+ deficiency using novel, appropriate biomarkers. Also, confirmation of gender-specific effect of NAD+-increasing treatments would be needed.

Prevention strategies for type 1 diabetes: a story of promising efforts and unmet expectations

A number of studies have investigated primary and secondary prevention strategies for type 1 diabetes (T1D), since early interventions might improve long-term outcomes through the amelioration of immune processes and the preservation of beta-cell mass. Primary prevention trials focus on genetically at-risk individuals prior to the appearance of autoimmunity, whereas secondary prevention trials aim to halt the progression of complete beta-cell destruction in subjects with established islet autoimmunity (IA). Different approaches have been tested so far, focusing on both pharmaceutical (insulin and monoclonal antibodies) and non-pharmaceutical (vitamin D, omega-3 fatty acids, probiotics, and nicotinamide) interventions, as well as on environmental factors that are believed to trigger autoimmunity in T1D (cow's milk, gluten, and bovine insulin). Albeit certain strategies have displayed efficacy in reducing IA development rates, most efforts have been unsuccessful in preventing the onset of the disease in high-risk individuals. Moreover, significant heterogeneity in study designs, included populations, and explored outcomes renders the interpretation of study results challenging. The aim of this narrative review is to present and critically evaluate primary and secondary prevention strategies for T1D, seeking to fill existing knowledge gaps and providing insight into future directions.

Niacinamide May Be Associated with Improved Outcomes in COVID-19-Related Acute Kidney Injury: An Observational Study

Background

AKI is a significant complication of coronavirus disease 2019 (COVID-19), with no effective therapy. Niacinamide, a vitamin B3 analogue, has some evidence of efficacy in non-COVID-19-related AKI. The objective of this study is to evaluate the association between niacinamide therapy and outcomes in patients with COVID-19-related AKI.

Methods

We implemented a quasi-experimental design with nonrandom, prospective allocation of niacinamide in 201 hospitalized adult patients, excluding those with baseline eGFR <15 ml/min per 1.73 m² on or off dialysis, with COVID-19-related AKI by Kidney Disease Improving Global Outcomes (KDIGO) criteria, in two hospitals with identical COVID-19 care algorithms, one of which additionally implemented treatment with niacinamide for COVID-19-related AKI. Patients on the niacinamide protocol (B3 patients) were compared against patients at the same institution before protocol commencement and contemporaneous patients at the non-niacinamide hospital (collectively, non-B3 patients). The primary outcome was a composite of death or RRT.

Results

A total of 38 out of 90 B3 patients and 62 out of 111 non-B3 patients died or received RRT. Using multivariable Cox proportional hazard modeling, niacinamide was associated with a lower risk of RRT or death (HR, 0.64; 95% CI, 0.40 to 1.00; P=0.05), an association driven by patients with KDIGO stage-2/3 AKI (HR, 0.29; 95% CI, 0.13 to 0.65; P=0.03; P interaction with KDIGO stage=0.03). Total mortality also followed this pattern (HR, 0.17; 95% CI, 0.05 to 0.52; in patients with KDIGO stage-2/3 AKI, P=0.002). Serum creatinine after AKI increased by 0.20 (SEM, 0.08) mg/dl per day among non-B3 patients with KDIGO stage-2/3 AKI, but was stable among comparable B3 patients (+0.01 [SEM, 0.06] mg/dl per day; P interaction=0.03).

Conclusions

Niacinamide was associated with lower risk of RRT/death and improved creatinine trajectory among patients with severe COVID-19-related AKI. Larger randomized studies are necessary to establish a causal relationship.

Metabolomics-related nutrient patterns at seroconversion and risk of progression to type 1 diabetes

OBJECTIVE

Our aim was to elucidate the role of diet in type 1 diabetes (T1D) by examining combinations of nutrient intake in the progression from islet autoimmunity (IA) to T1D.

METHODS

We measured 2457 metabolites and dietary intake at the time of seroconversion in 132 IA-positive children in the prospective Diabetes Autoimmunity Study in the Young. IA was defined as the first of two consecutive visits positive for at least one autoantibody (insulin, GAD, IA-2, or ZnT8). By December 2018, 40 children progressed to T1D. Intakes of 38 nutrients were estimated from semiquantitative food frequency questionnaires. We tested the association of each metabolite with progression to T1D using multivariable Cox regression. Nutrient patterns that best explained variation in candidate metabolites were identified using reduced rank regression (RRR), and their association with progression to T1D was tested using Cox regression adjusting for age at seroconversion and high-risk HLA genotype.

RESULTS

In stepwise selection, 22 nutrients significantly predicted at least two of the 13 most significant metabolites associated with progression to T1D, and were included in RRR. A nutrient pattern corresponding to intake lower in linoleic acid, niacin, and riboflavin, and higher in total sugars, explained 18% of metabolite variability. Children scoring higher on this metabolite-related nutrient pattern at seroconversion had increased risk for progressing to T1D (HR = 3.17, 95%CI = 1.42-7.05).

CONCLUSIONS

Combinations of nutrient intake reflecting candidate metabolites are associated with increased risk of T1D, and may help focus dietary prevention efforts.

Nicotinamide for photoprotection and skin cancer chemoprevention: A review of efficacy and safety

Nicotinamide is a water-soluble vitamin B3 derivative that has many roles in medicine. This review examines the role of nicotinamide in dermatology and its actions in preventing photoageing and skin cancers in humans. Nicotinamide prevents ultraviolet radiation (UV) from reducing ATP levels and inhibiting glycolysis, thus preventing the UV radiation-induced energy crisis. This enhances DNA repair and reduces UV-induced suppression of immunity. Randomised controlled clinical trials have also shown that nicotinamide reduces transepidermal water loss and the development of new non-melanoma skin cancers in high-risk humans. This review also examines nicotinamide's safety profile.

Clinical Evidence for Targeting NAD Therapeutically

Nicotinamide adenine dinucleotide (NAD) pharmacology is a promising class of treatments for age-related conditions that are likely to have a favorable side effect profile for human use, given the widespread use of the NAD precursor vitamin B3 supplements. However, despite several decades of active investigation and numerous possible biochemical mechanisms of action suggested, only a small number of randomized and adequately powered clinical trials of NAD upregulation as a therapeutic strategy have taken place. We conducted a systematic review of the literature, following the PRISMA guidelines, in an attempt to determine whether or not the human clinical trials performed to date support the potential benefits of NAD supplementation in a range of skin, metabolic and age-related conditions. In addition, we sought medical indications that have yielded the most promising results in the limited studies to date. We conclude that promising, yet still speculative, results have been reported for the treatment of psoriasis and enhancement of skeletal muscle activity. However, further trials are required to determine the optimal method of raising NAD levels, identifying the target conditions, and comparisons to the present standard of care for these conditions. Lastly, pharmacological methods that increase NAD levels should also be directly compared to physiological means of raising NAD levels, such as exercise programs and dietary interventions that are tailored to older individuals, and which may be more effective.

Precision medicine in diabetes: a Consensus Report from the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD)

The convergence of advances in medical science, human biology, data science and technology has enabled the generation of new insights into the phenotype known as 'diabetes'. Increased knowledge of this condition has emerged from populations around the world, illuminating the differences in how diabetes presents, its variable prevalence and how best practice in treatment varies between populations. In parallel, focus has been placed on the development of tools for the application of precision medicine to numerous conditions. This Consensus Report presents the American Diabetes Association (ADA) Precision Medicine in Diabetes Initiative in partnership with the European Association for the Study of Diabetes (EASD), including its mission, the current state of the field and prospects for the future. Expert opinions are presented on areas of precision diagnostics and precision therapeutics (including prevention and treatment) and key barriers to and opportunities for implementation of precision diabetes medicine, with better care and outcomes around the globe, are highlighted. Cases where precision diagnosis is already feasible and effective (i.e. monogenic forms of diabetes) are presented, while the major hurdles to the global implementation of precision diagnosis of complex forms of diabetes are discussed. The situation is similar for precision therapeutics, in which the appropriate therapy will often change over time owing to the manner in which diabetes evolves within individual patients. This Consensus Report describes a foundation for precision diabetes medicine, while highlighting what remains to be done to realise its potential. This, combined with a subsequent, detailed evidence-based review (due 2022), will provide a roadmap for precision medicine in diabetes that helps improve the quality of life for all those with diabetes.

Prevention of Type 1 Diabetes: Past Experiences and Future Opportunities

Type 1 diabetes (T1D) results from autoimmune destruction of insulin-producing beta-cells in the pancreas, caused by the interplay of genetic and environmental factors. Despite the introduction of advanced technologies for diabetes management, most patients fail to achieve target glycemic control, and T1D still has a high burden of long-term end-organ complications. Over several decades, multiple clinical trials have attempted to find prevention for T1D in at-risk individuals or to stabilize, ultimately reverse, the disease in those with T1D. To date, T1D remains yet incurable condition; however, recently improved understanding of the natural history of the disease may lead to new strategies to preserve or improve beta-cell function in those at increased risk and T1D patients. This publication aims to provide an overview of past experiences and recent findings in the prevention of T1D.

Short-term effects induced by nicotinamide in ovariectomized females

Nicotinamide adenine dinucleotide (NAD)⁺ precursors such as nicotinamide activate sirtuins and enhance energy metabolism. The aim of this study was to evaluate the metabolic effects of nicotinamide in ovariectomized (OVX) female rats to establish molecular targets against obesity, which support the safe therapeutic application of nicotinamide. The OVX animals were divided into groups: SHAM (simulated surgery), SHAMn (two weeks of 35 mg·kg^-1 nicotinamide per day, by gavage), OVX, and OVXn (two weeks of 35 mg·kg^-1 nicotinamide per day, by gavage). The results indicated that nicotinamide favored lipolysis, as evidenced by an increase in free fatty acid and hepatic triglyceride levels, which were not fully normalized during the treatment period. The lipolysis appeared to be due to increased SIRT1 and mitochondrial oxidative phosphorylation in muscle and adipose tissue. There were decreases in muscle and fat nicotinamide N-methyltransferase (NNMT), which were associated with decreases in mass and triglyceride, low-density lipoprotein cholesterol (LDLc), and total cholesterol content. Nicotinamide appeared to be beneficial for the glycemic profile, with normal hepatic glycogen storage and a tendency towards insulin sensitivity in the OVXn. In the SHAMn group, nicotinamide led to glucose intolerance, together with reduced muscle expressions of nicotinamide phosphoribosyltransferase (NAMPT) and SIRT3, suggesting that there were no short-term benefits. Supplementation with nicotinamide led to tissue-specific adaptive lipid and molecular changes in OVX rats.

Biological Efficacy and Safety of Niacinamide in Patients With ADPKD

INTRODUCTION

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by progressive cyst enlargement, leading to kidney failure. Sirtuin-1 is upregulated in ADPKD and accelerates disease progression by deacetylating p53. Niacinamide is a dietary supplement that inhibits sirtuins at high doses.

METHODS

We conducted an open-label, single-arm intervention trial (study 1, N = 10), and a randomized, double blinded, placebo-controlled trial (study 2, N = 36) to assess the biological activity and safety of niacinamide. Patients with ADPKD were given 30 mg/kg oral niacinamide or placebo, for 12 months. The primary endpoint was the ratio of acetylated p53 to total p53 protein in peripheral blood mononuclear cells (PBMCs).

RESULTS

There was no sustained effect of niacinamide on acetylated/total p53 in either study and no difference between placebo and niacinamide arms. There was no difference in the change in height-adjusted total kidney volume over 12 months between niacinamide and placebo. Niacinamide was generally well tolerated. The most common adverse effects were nausea, diarrhea, gastroesophageal reflux, headache, and acneiform rash but there was no difference in their incidence between niacinamide and placebo.

CONCLUSIONS

In conclusion, niacinamide is safe and well-tolerated in patients with ADPKD. However, we were unable to detect a sustained inhibition of sirtuin activity over 12 months of treatment, and there was no signal to suggest a beneficial effect on any efficacy measure.

Impaired nicotinamide adenine dinucleotide (NAD+ ) metabolism in diabetes and diabetic tissues: Implications for nicotinamide-related compound treatment

One of the biochemical abnormalities found in diabetic tissues is a decrease in the cytosolic oxidized to reduced forms of the nicotinamide adenine dinucleotide ratio (NAD⁺/NADH also known as pseudohypoxia) caused by oxidation of excessive substrates (glucose through the polyol pathway, free fatty acids and lactate). Subsequently, a decline in NAD⁺ levels as a result of the activation of poly adenine nucleotide diphosphate‐ribose polymerase (mainly in type 1 diabetes) or the inhibition of adenine nucleotide monophosphate‐activated protein kinase (in type 2 diabetes). Thus, replenishment of NAD⁺ levels by nicotinamide‐related compounds could be beneficial. However, these compounds also increase nicotinamide catabolites that cause oxidative stress. This is particularly troublesome for patients with diabetes, because they have impaired nicotinamide salvage pathway reactions at the level of nicotinamide phosphoribosyl transferase and phosphoribosyl pyrophosphate, which occurs by the following mechanisms. First, phosphoribosyl pyrophosphate synthesis from pentose phosphate pathway is compromised by a decrease in plasma thiamine and transketolase activity. Second, nicotinamide phosphoribosyl transferase expression is decreased because of reduced adenosine monophosphate‐activated protein kinase activity, which occurs in type 2 diabetes. The adenosine monophosphate‐activated protein kinase inhibition is caused by an activation of protein kinase C and D1 as a result of enhanced diacylglycerol synthesis caused by pseudohypoxia and increased fatty acids levels. In this regard, nicotinamide‐related compounds should be given with caution to treat diabetes. To minimize the risk and maximize the benefit, nicotinamide‐related compounds should be taken with insulin sensitizers (for type 2 diabetes), polyphenols, benfotiamine, acetyl‐L‐carnitine and aldose reductase inhibitors. The efficacy of these regimens can be monitored by measuring serum NAD⁺ and urinary nicotinamide catabolites.

Precision Medicine in Diabetes: A Consensus Report From the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD)

The convergence of advances in medical science, human biology, data science, and technology has enabled the generation of new insights into the phenotype known as "diabetes." Increased knowledge of this condition has emerged from populations around the world, illuminating the differences in how diabetes presents, its variable prevalence, and how best practice in treatment varies between populations. In parallel, focus has been placed on the development of tools for the application of precision medicine to numerous conditions. This Consensus Report presents the American Diabetes Association (ADA) Precision Medicine in Diabetes Initiative in partnership with the European Association for the Study of Diabetes (EASD), including its mission, the current state of the field, and prospects for the future. Expert opinions are presented on areas of precision diagnostics and precision therapeutics (including prevention and treatment), and key barriers to and opportunities for implementation of precision diabetes medicine, with better care and outcomes around the globe, are highlighted. Cases where precision diagnosis is already feasible and effective (i.e., monogenic forms of diabetes) are presented, while the major hurdles to the global implementation of precision diagnosis of complex forms of diabetes are discussed. The situation is similar for precision therapeutics, in which the appropriate therapy will often change over time owing to the manner in which diabetes evolves within individual patients. This Consensus Report describes a foundation for precision diabetes medicine, while highlighting what remains to be done to realize its potential. This, combined with a subsequent, detailed evidence-based review (due 2022), will provide a roadmap for precision medicine in diabetes that helps improve the quality of life for all those with diabetes.

Cause or effect? A review of clinical data demonstrating beta cell dysfunction prior to the clinical onset of type 1 diabetes

Background

Limited successes of conventional approaches to type 1 diabetes (T1D) prevention and treatment have highlighted the need for improved understanding of risk factors contributing to or hastening progression to clinical diagnosis.

Scope of review

This review summarizes beta cell function metabolic phenotyping data from clinical studies conducted in at-risk individuals before T1D onset and healthy controls. Data are drawn from studies comparing at-risk individuals who progress to T1D to at-risk individuals who do not progress to T1D, as well as from studies comparing at-risk individuals to controls without a T1D family history.

Major conclusions

Rapid loss of beta cell insulin secretion occurs in the months immediately preceding clinical onset. However, evidence of beta cell dysfunction is present even years earlier. Comparisons to controls without a family history suggest that many individuals in families impacted by T1D have evidence of beta cell dysfunction, even individuals who are unlikely to develop clinical disease. These findings may mean that underlying metabolic beta cell dysfunction contributes to T1D development and may explain some of the heterogeneity observed in the disease.