Vitamin K: A vital micronutrient with the cardioprotective potential against diabetes-associated complications

An L-shaped relationship between dietary vitamin K and atherosclerotic cardiovascular disease

BACKGROUND AND AIMS

Few studies link vitamin K intake with incident atherosclerotic cardiovascular disease (ASCVD), and the specific mechanism remains uncertain. We aimed to evaluate the relationship between dietary vitamin K and ASCVD.

METHODS

This study used cross-sectional data from people over 20 years old who took part in the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2018. Vitamin K intake was assessed using a 24-h dietary review. The Patient Medical Conditions Questionnaire was used to assess ASCVD. The stability of the outcomes was evaluated using cubic spline models with restricted parameters and logistic regression, while subgroup analyses were also performed.

RESULTS

There were 14,465 participants, with 9.78% (1415/14,465) who diagnosed with ASCVD. Compared with individuals with lower vitamin K intake Q1 (≤39.0 ug/day), the adjusted OR values for dietary vitamin K intake and ASCVD in Q2 (39.1-70.8 ug/day), Q3 (70.9-131.0 mg/day), and Q4 (≥131.1 ug/day) were 0.88 (95% CI: 0.74-1.04, p = 0.134), 0.77(95% CI: 0.65-0.93, p = 0.005), and 0.78 (95% CI: 0.65-0.95, p = 0.013), respectively. The association between dietary vitamin K intake and ASCVD showed an L-shaped curve (nonlinear, p = 0.006). The OR for ASCVD in participants with vitamin K intake <127.1ug/day was 0.996 (95% CI: 0.993-0.998, p = 0.002).

CONCLUSIONS

The relationship between dietary vitamin K intake and ASCVD was L-shaped curve in US adults, the inflection point was roughly 127.1 ug/day.

Associations Between Vitamin K and Suicide Attempts in Patients with Depression: A Case-Control Study

Background

Hypovitaminosis K has been linked to depression and suicide, but epidemiological research is scarce. This study aimed to explore the association among vitamin K with depression and suicidal attempts.

Methods

This was a retrospective cross-sectional study involving 146 cases with a history of suicidal attempts and 149 subjects without a lifetime history of suicidal attempts. The levels of thyroid hormones, lipid profile, inflammatory cytokines, and vitamins were measured.

Results

Subjects who had suicidal attempts presented with a significant decrease in FT4, TC, vitamin D, and vitamin K but increased CRP levels. In these variables, vitamin K has a better diagnostic value for suicidal attempts in depressed patients, with a sensitivity of 0.842 and a specificity of 0.715. Correlation analysis suggested that vitamin K was significantly and positively related to FT4, TC, LDL, and sdLDL. Multivariate analysis showed that serum vitamin K level predicts suicidal attempts in depressive patients (OR = 0.614, P = 0.004, 95% CI 0.153-0.904). Moreover, a negative correlation between vitamin K and suicidal attempts was also noted for partial FT4, CRP, and vitamin D strata analysis.

Conclusion

Our study suggests that low vitamin K levels were correlated with suicidal attempts in patients with depression, indicating that vitamin K deficiency might be a biological risk factor for depression.

The association between vitamin K intake and dyslipidemia in US adults: the mediating effect of insulin resistance

Background: Dyslipidemia is one of the most common chronic diseases, and is associated with insulin resistance (IR) and inadequate vitamin K intake. We aimed to explore the association between IR, vitamin K intake, and dyslipidemia, and further to explore the mediating role of IR. Materials and methods: 12 860 participants from the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2018 were included in this study. Insulin resistance was determined by using the homeostatic model assessment for insulin resistance (HOMA-IR). Weighted multiple logistic regression and mediation analyses were conducted to analyze the associations between IR, vitamin K intake, and dyslipidemia. Results: We found that both vitamin K intake-met Dietary Reference Intake (DRI) and non-IR were protective factors of high triglycerides (with ORs (95% CI) of 0.71 (0.57, 0.87) and 0.36 (0.29, 0.45), respectively) and low high-density lipoprotein cholesterol (with ORs (95% CI) of 0.72 (0.62, 0.82) and 0.39 (0.34, 0.41), respectively). IR-related indicators (HOMA-IR and insulin) partly mediated these effects, and the proportion ranged from 16.36% to 18.52%. Conclusion: Vitamin K intake-met DRI and non-IR were associated with lower risk of dyslipidemia including high TG and low HDL-C. IR partly mediated the association of vitamin K intake with high TG and low HDL-C.

The effect of vitamin K4 supplementation on insulin resistance in individuals with type 2 diabetes: a double-blind randomised placebo-controlled clinical trial

PURPOSE

The purpose of this study was to assess the possible clinical effects of vitamin K4 supplementation in individuals with type 2 diabetes namely insulin resistance, glycaemic control, and lipid profile.

METHODS

This was a prospective randomised double-blind placebo-controlled clinical trial. A total of 106 patients were randomised to receive either 1 mg of vitamin K4 (menadiol diacetate) or placebo for 24 weeks.

RESULTS

Ninety patients (n = 45 in each study group) were included in the final analysis. After 24 weeks, homeostatic model assessment of insulin resistance (HOMA-IR) (16.54 ± 7.81 vs. 29.09 ± 36.56, P = 0.027) and fasting serum insulin (FSI) (6.86 ± 3.45 vs. 11.13 ± 12.66 µU/ml, P = 0.032) were significantly lower in the vitamin K group compared to placebo. Additionally, triglycerides (TG) (144.94 ± 50.7 vs. 172.8 ± 101.5 mg/dl, P = 0.031) and very low-density lipoproteins (VLDL) levels (28.9 ± 9.88 vs. 34.6 ± 20.30 mg/dl, P = 0.027) decreased significantly in the vitamin K group after 24 weeks compared to baseline. Moreover, more patients in the vitamin K group (35.6%) had their antidiabetic medication doses reduced after 24 weeks compared to placebo (13.3%, P = 0.029).

CONCLUSION

Vitamin K4 supplementation for 24 weeks is capable of improving insulin resistance and TG levels in individuals with type 2 diabetes. In addition, the improvement in insulin resistance was reflected in the decrease in antidiabetic medication doses. However, it did not affect fasting plasma glucose (FPG) or glycated haemoglobin (HbA1c).

TRIAL REGISTRATION

The study was registered on clinicaltrials.gov with ID: NCT04285450.

Modulatory Properties of Vitamin D in Type 2 Diabetic Patients: A Focus on Inflammation and Dyslipidemia

BACKGROUND

Evidence from preclinical studies has found a correlation between the development of type 2 diabetes (T2D) and vitamin D deficiency. However, evidence from randomized controlled trials (RCTs) revealed inconclusive results on vitamin D supplementation. We explored the effect of vitamin D on inflammation and dyslipidemia in T2D.

METHODS

We comprehensively searched for RCTs evaluating the effect of vitamin D in T2D on PubMed. Data were analyzed using Review Manager 5.3 and reports, such as standardized mean difference (SMD) and 95% confidence intervals (CI) at a 5% significant level using a random effect model.

RESULTS

This study revealed a significant reduction in tumor necrosis factor-alpha (TNF-α) SMD = (-0.51, 95%CI (-0.93, -0.09); p = 0.02), high sensitivity C-reactive protein (hs-CRP) SMD = (-1.06, 95%CI (-1.67, -0.45); p < 0.05) in vitamin D compared to placebo. Additionally, interleukin-6 (IL-6) exhibited a marginal effect SMD = (-0.52, 95%CI (-1.05, 0.01), p = 0.05). Furthermore, a significant reduction in the level of triglycerides SMD = (-0.65, 95%CI (-1.11, -0.18), p < 0.05) was observed, concomitant to a significantly increased high-density lipoprotein (HDL) level SMD = (0.53, 95%CI (0.08, 0.98), p = 0.02). However, no statistically significant changes were observed in total cholesterols SMD = (-0.16, 95%CI (-0.57, 0.24), p = 0.43) and low-density lipoprotein (LDL) SMD = (-0.06, 95%CI (-0.37, 0.24), p = 0.67).

CONCLUSIONS

These findings suggest that vitamin D supplementation may be beneficial in ameliorating inflammation and dyslipidemia in T2D patients.

A Review on the Antidiabetic Properties of Moringa oleifera Extracts: Focusing on Oxidative Stress and Inflammation as Main Therapeutic Targets

Moringa oleifera is one of the popular plants that have shown significant health benefits. Certainly, preclinical evidence (predominantly from animal models) summarized in the current review supports the beneficial effects of Moringa oleifera leaf extracts in combating the prominent characteristic features of diabetes mellitus. This includes effective control of blood glucose or insulin levels, enhancement of insulin tissue sensitivity, improvement of blood lipid profiles, and protecting against organ damage under sustained conditions of hyperglycemia. Interestingly, as major complications implicated in the progression of diabetes, including organ damage, Moringa oleifera leaf and seed extracts could efficiently block the detrimental effects of oxidative stress and inflammation in these preclinical models. Notably, these extracts (especially leaf extracts) showed enhanced effects in strengthening intracellular antioxidant defences like catalase, superoxide dismutase, and glutathione to lower lipid peroxidation products and reduce prominent pro-inflammatory markers such as tumor necrosis factor-α, interleukin (1L)-β, IL-6, monocyte chemoattractant protein-1 and nitric oxide synthase. From animal models of diabetes, the common and effective dose of leaf extracts of Moringa oleifera was 100-300 mg/kg, within the treatment duration of 2-8 weeks. Whereas supplementation with approximately 20 g leaf powder of Moringa oleifera for at least 2 weeks could improve postprandial blood glucose in subjects with prediabetes or diabetes. Although limited clinical studies have been conducted on the antidiabetic properties of Moringa oleifera, current findings provide an important platform for future research directed at developing this plant as a functional food to manage diabetic complications.

Is the Risk of Diabetes Lower in Patients With Atrial Fibrillation Treated With Direct Oral Anticoagulant Compared to Warfarin?

Background

The use of anticoagulants is an established strategy to prevent stroke, embolism, and cardiovascular mortality in patients with atrial fibrillation (AF), but its role in the prevention of incident diabetes is unclear. We aimed to investigate this question by using participant data from cohort studies.

Methods

We conducted a meta-analysis of participants to investigate the impact of direct oral anticoagulants (DOACs) on the risk of new-onset diabetes in AF patients. The collection of related data was performed in the PubMed and EMBASE databases until December 2021, including studies associated with evaluating the correlation between DOACs and incident diabetes. The hazard ratios (HRs) and 95% confidence intervals (CIs) were adjusted by the random-effects model with an inverse variance method.

Results

Two cohort studies with a total of 24,434 patients were included in this study (warfarin: n = 6,906; DOACs: n = 17,528). Compared with warfarin, the use of DOACs could reduce the incident diabetic risk in AF patients (HR = 0.75, 95%CI: 0.68–0.82). Investigations about the effects of three major classes of DOACs showed that the individual use of dabigatran (HR = 0.76, 95%CI: 0.64–0.90), rivaroxaban (HR = 0.74, 95%CI: 0.64–0.87), apixaban (HR = 0.74, 95%CI: 0.60–0.92) and the combined use of rivaroxaban and apixaban (HR = 0.74, 95%CI: 0.66–0.84) could reduce the risk of new-onset diabetes compared with warfarin. This risk reduction effect could be observed in both male and female groups (HR = 0.73, 95%CI: 0.64–0.84, P &lt; 0.00001; HR = 0.82, 95%CI: 0.82–0.99, P = 0.04).

Conclusions

Treatment with DOACs compared with warfarin reduced the risk of new-onset diabetes in both male and female patients with AF.

Role of Vitamin K in Chronic Kidney Disease: A Focus on Bone and Cardiovascular Health

Chronic kidney disease (CKD) is commonly associated with vitamin K deficiency. Some of the serious complications of CKD are represented by cardiovascular disease (CVD) and skeletal fragility with an increased risk of morbidity and mortality. A complex pathogenetic link between hormonal and ionic disturbances, bone tissue and metabolism alterations, and vascular calcification (VC) exists and has been defined as chronic kidney disease–mineral and bone disorder (CKD-MBD). Poor vitamin K status seems to have a key role in the progression of CKD, but also in the onset and advance of both bone and cardiovascular complications. Three forms of vitamin K are currently known: vitamin K1 (phylloquinone), vitamin K2 (menaquinone), and vitamin K3 (menadione). Vitamin K plays different roles, including in activating vitamin K-dependent proteins (VKDPs) and in modulating bone metabolism and contributing to the inhibition of VC. This review focuses on the biochemical and functional characteristics of vitamin K vitamers, suggesting this nutrient as a possible marker of kidney, CV, and bone damage in the CKD population and exploring its potential use for promoting health in this clinical setting. Treatment strategies for CKD-associated osteoporosis and CV disease should include vitamin K supplementation. However, further randomized clinical studies are needed to assess the safety and the adequate dosage to prevent these CKD complications.

Impact of physical exercise and caloric restriction in patients with type 2 diabetes: Skeletal muscle insulin resistance and mitochondrial dysfunction as ideal therapeutic targets

Skeletal muscle insulin resistance and mitochondrial dysfunction are some of the major pathological defects implicated in the development of type 2 diabetes (T2D). Therefore, it has become necessary to understand how common interventions such as physical exercise and caloric restriction affect metabolic function, including physiological processes that implicate skeletal muscle dysfunction within a state of T2D. This review critically discusses evidence on the impact of physical exercise and caloric restriction on markers of insulin resistance and mitochondrial dysfunction within the skeletal muscle of patients with T2D or related metabolic complications. Importantly, relevant information from clinical studies was acquired through a systematic approach targeting major electronic databases and search engines such as PubMed, Google Scholar, and Cochrane library. The reported evidence suggests that interventions like physical exercise and caloric restriction, within a duration of approximately 2 to 4 months, can improve insulin sensitivity, in part by targeting the phosphoinositide 3-kinases/protein kinase B pathway in patients with T2D. Furthermore, both physical exercise and caloric restriction can effectively modulate markers related to improved mitochondrial function and dynamics. This was consistent with an improved modulation of mitochondrial oxidative capacity and reduced production of reactive oxygen species in patients with T2D or related metabolic complications. However, such conclusions are based on limited evidence, additional clinical trials are required to better understand these interventions on pathological mechanisms of T2D and related abnormalities.