Causal Associations Between Circulating Adipokines and Cardiovascular Disease: A Mendelian Randomization Study

Increased circulating apolipoprotein Cs are implicated in the association between elevated serum retinol and retinol-binding protein 4 and adverse progression of metabolic syndrome in adults: A prospective study

Prior research has highlighted the significant roles of circulating retinol, retinol-binding protein 4 (RBP4), and apolipoprotein C (ApoC) in metabolic health. This study investigates the joint association of retinol and RBP4 with metabolic syndrome (MetS) and examines the potential mediating role of ApoCs in these relationships. This prospective study included 3,009 and 2,724 participants with baseline serum retinol and RBP4 data, respectively. Over a 9-year follow-up among 2,621 participants, 1,136, 127, 696, and 662 were categorized into MetS-free, recovered, incident MetS, and persistent MetS groups, respectively. Midway through the study, ApoC1-4 levels were measured in 2316 participants. Adjusted odds ratios (95% CIs) for the highest (vs. lowest) tertile of retinol and RBP4 levels were 3.63 (2.69-4.92) and 5.64 (4.05-7.92) for 9-year persistent MetS, respectively. The corresponding hazard ratios (95% CIs) were 1.67 (1.39-2.01) and 1.67(1.38, 2.03) for incident MetS, and 0.65 (0.41-1.03) and 0.44 (0.28, 0.70) for recovered MetS (all P-trends<.05). A synergistic association of retinol and RBP4 with MetS risk was observed for persistent MetS. Higher levels of retinol or RBP4 were associated with increased concentrations of ApoC1-4, which were linked to a greater risk of incident and persistent MetS. A newly developed composite score (ApoCS), derived from ApoC1-4 levels, explained 30.5% and 24.5% of the association between retinol or RBP4 and MetS, with ApoC2 and ApoC3 contributing predominantly to this connection. Our study identified notable positive correlations between serum retinol and RBP4 levels and MetS progression, explained by increases in circulating ApoC2 and ApoC3 within a Chinese cohort.

Diabetes affects AD through plasma Aβ40: A Mendelian randomization study

Amyloid and tau proteins are important proteins in the pathological changes of Alzheimer's disease (AD), while Aβ pathology and tau pathology are the most critical factors contributing to the development of AD. Some studies have shown that there is a causal relationship between AD and diabetes mellitus, but there are no studies showing a causal relationship between diabetic traits and AD biomarkers, so further exploration is needed. We first summarized and analyzed the currently published literature on the link between diabetes and AD through a systematic review. Forest plots were used to observe whether there is an association between diabetes and AD. Then a two-sample Mendelian randomization (MR) analysis based on GWAS summary statistics was performed to verify the causal relationship between diabetic traits and AD biomarkers. Based on summary statistics from the GWAS, potential causal relationships between diabetic traits and AD biomarkers were explored separately. The results of the meta-analysis part showed that diabetes can increase the risk of AD. Meanwhile, our two-sample MR results showed a significant causal relationship between diabetes and plasma Aβ40. In addition, our two-sample MR results also showed a causal relationship between increased HbA1c and plasma APLP2. Other diabetic traits may have potential effects on different AD plasma markers.

The Causal Relationship between Telomere Length and Cancer Risk: A Two-Sample Mendelian Randomization

BACKGROUND

Telomere length (TL) shortens with age and is associated with an increased risk of numerous chronic diseases. However, the causal direction of the association between TL and cancer risk remains uncertain. This study aimed to assess the causal impact of TL on cancer risk using Mendelian randomization (MR) analysis.

METHODS

Genome-wide association studies from Singapore and China data, the Korean Cancer Prevention Study II (KCPS-II), the Korean Genome Epidemiologic Study, and the Biobank of Japan were utilized. A two-sample MR study was performed using summary-level genome-wide association study data from individuals of East Asian ancestry. SNPs associated with TL were used as instrumental variables.

RESULTS

Longer TL per 1-SD increase due to germline genetic variants was associated with a higher risk of site-specific cancer. In the KCPS-II and Korean Genome Epidemiologic Study, the strongest association was observed with thyroid cancer {OR, 2.49 [95% confidence interval (CI), 1.79-3.47] and 2.27 (1.49-3.46)}, followed by lung cancer [OR, 2.19 (95% CI, 1.60-3.08) and 1.45 (1.12-1.87)]. Similar results were observed in the Biobank of Japan, with OR, 2.92 (95% CI, 1.75-4.88) for thyroid cancer and 2.04 (1.41-2.94) for lung cancer. In histologic subgroup analysis of KCPS-II, a significant relationship was found with lung adenocarcinoma [OR, 2.26 (95% CI, 1.55-3.31)] but not with lung squamous cell carcinoma (1.21, 0.47-3.06). After removing outlier SNPs in the radial MR analysis, significant associations were identified for both lung adenocarcinoma [OR, 1.88 (95% CI, 1.25-2.82)] and lung squamous cell carcinoma (2.29, 1.05-4.98).

CONCLUSIONS

Our findings suggest that longer TL increases the risk of various cancers in East Asian populations.

IMPACT

Genetically determined longer TL may contribute to a risk of certain cancers.

Does ankylosing spondylitis exert a bidirectional influence on hypertension? A two-sample Mendelian randomization study

Objective

Previous observational studies reported that ankylosing spondylitis is closely related to hypertension. However, it is still controversial whether the association between ankylosing spondylitis and hypertension is causal. The effects of ankylosing spondylitis on diastolic and systolic blood pressure deserve further investigation. The objective of our study is to explore whether ankylosing spondylitis is causally associated with blood pressure.

Methods

A bidirectional two-sample Mendelian randomization (MR) analysis was performed by employing five Mendelian randomization analysis methods. MR Egger regression, weighted median, inverse variance weighted, and weight mode methods were performed in the two-sample Mendelian randomization analysis. We performed Mendelian randomization to investigate the association between ankylosing spondylitis (finn-b-M13_ANKYLOSPON) and hypertension (ukb-b-14057), diastolic blood pressure (ebi-a-GCST90000062) and systolic blood pressure (ebi-a-GCST90000059). We also performed reverse Mendelian randomization between exposures and outcomes. Another new validation cohort (ukb-b-18194) was also performed. The heterogeneity, horizontal pleiotropy, and possible outliers were examined in the MR analysis results.

Results

The inverse variance weighted results showed that ankylosing spondylitis has no genetic causal relationship with hypertension (p = 0.441, OR = 1.001, 95% CI: 0.999-1.002). The inverse variance weighted results showed that ankylosing spondylitis has no genetic causal relationship with systolic blood pressure (p = 0.301, OR = 1.006, 95% CI: 0.995-1.018). The inverse variance weighted results showed that ankylosing spondylitis has no genetic causal relationship with diastolic blood pressure (p = 0.778, OR = 1.002, 95% CI: 0.988-1.016). The reverse Mendelian randomization between exposures and outcomes is negative. Another new validation cohort also confirmed the results. No heterogeneity was observed by the MR-pleiotropy residual sum and outlier test. The "leave-one-out" analysis indicated that the results of MR analysis were not affected by a single nucleotide polymorphism.

Conclusion

This study represents the first two-sample Mendelian randomization analysis aimed at investigating the causal genetic relationship between ankylosing spondylitis and blood pressure. Our Mendelian randomization analysis results revealed a lack of causal association between ankylosing spondylitis and hypertension, diastolic blood pressure, as well as systolic blood pressure.

Investigating casual association among gut microbiome and esophageal cancer: A Mendelian randomization study

The gut microbiota has been strongly linked to gastrointestinal cancer, but the relationship between gut microbiota and esophageal cancer (EC) is still not fully understood. We conducted a 2-sample Mendelian randomization (MR) study to unveil the potential impact of intestinal microorganisms on EC in East Asian populations. In order to delve deeper into the potential causal relationship between gut microbiota and EC, we conducted a 2-sample MR analysis, utilizing 211 single nucleotide polymorphisms associated with gut microbiota, sourced from the largest genome-wide association study on gut microbiota, for our analysis. To estimate the causal relationship, we employed the inverse variance weighting method. In addition, to assess the potential influence of pleiotropy, we used MR-Egger regression in our analysis. Among the 10 specific bacterial taxa identified using the inverse variance weighting as being associated with the risk of EC, we observed a positive association between family Bacteroidaceae (P = .04), genus Bacteroides (P = .04), genus Bilophila (P = .02), genus Candidatus Soleaferrea (P = .02) and the EC, while family Victivallaceae (P = .03), genus Eubacterium coprostanoligenes (P = .01), genus Catenibacterium (P = .01), genus Coprococcus2 (P = .01), unknowngenus.id.959 (P = .02) and unknowngenus.id.1868 (P = .01) may be associated with a reduced risk of EC. Our MR analysis indicate a probable association between gut microbiota and the development and advancement of EC. These findings offer novel perspectives on the possible application of targeted gut bacteria for the prevention and management of EC.

Can Exercise-Mediated Adipose Browning Provide an Alternative Explanation for the Obesity Paradox?

Overweight patients with cardiovascular disease (CVD) tend to survive longer than normal-weight patients, a phenomenon known as the "obesity paradox". The phenotypic characteristics of adipose distribution in these patients (who survive longer) often reveal a larger proportion of subcutaneous white adipose tissue (scWAT), suggesting that the presence of scWAT is negatively associated with all-cause mortality and that scWAT appears to provide protective benefits in patients facing unhealthy states. Exercise-mediated browning is a crucial aspect of the benign remodeling process of adipose tissue (AT). Reduced accumulation, reduced inflammation, and associated adipokine secretion are directly related to the reduction in CVD mortality. This paper summarized the pathogenetic factors associated with AT accumulation in patients with CVD and analyzed the possible role and pathway of exercise-mediated adipose browning in reducing the risk of CVD and CVD-related mortality. It is suggested that exercise-mediated browning may provide a new perspective on the "obesity paradox"; that is, overweight CVD patients who have more scWAT may gain greater cardiovascular health benefits through exercise.

Adipokines and their potential impacts on susceptibility to myocardial ischemia/reperfusion injury in diabetes

Coronary artery disease has a high mortality rate and is a striking public health concern, affecting a substantial portion of the global population. On the early onset of myocardial ischemia, thrombolytic therapy and coronary revascularization could promptly restore the bloodstream and nutrient supply to the ischemic tissue, efficiently preserving less severely injured myocardium. However, the abrupt re-establishment of blood flow triggers the significant discharge of previously accumulated oxidative substances and inflammatory cytokines, leading to further harm referred to as ischemia/reperfusion (I/R) injury. Diabetes significantly raises the vulnerability of the heart to I/R injury due to disrupted glucose and lipid processing, impaired insulin sensitivity and metabolic signaling, and increased inflammatory responses. Numerous studies have indicated that adipokines are crucial in the etiology and pathogenesis of obesity, diabetes, hyperlipidemia, hypertension, and coronary artery disease. Adipokines such as adiponectin, adipsin, visfatin, chemerin, omentin, and apelin, which possess protective properties against inflammatory activity and insulin resistance, have been shown to confer myocardial protection in conditions such as atherosclerosis, myocardial hypertrophy, myocardial I/R injury, and diabetic complications. On the other hand, adipokines such as leptin and resistin, known for their pro-inflammatory characteristics, have been linked to elevated cardiac lipid deposition, insulin resistance, and fibrosis. Meteorin-like (metrnl) exhibits opposite effects in various pathological conditions. However, the data on adipokines in myocardial I/R, especially in diabetes, is still incomplete and controversial. This review focuses on recent research regarding the categorization and function of adipokines in the heart muscle, and the identification of different signaling pathways involved in myocardial I/R injury under diabetic conditions, aiming to facilitate the exploration of therapeutic strategies against myocardial I/R injury in diabetes.

Associations between daytime napping, sleep duration, and depression and 15 cardiovascular diseases: a Mendelian randomization study

Background

Numerous studies have documented the effects of daytime napping, sleep duration, and depression on cardiovascular diseases (CVDs). However, the evidence has been gleaned from observational studies that might be riddled with confounding variables and the possibility of reverse causation bias. Therefore, the present study employed a Mendelian randomization (MR) methodology to meticulously explore the relationships between daytime napping, sleep duration, and depression, and the risk profiles of CVDs.

Methods

Genome-wide significant genetic variants associated with daytime napping, sleep duration, and depression were used as the instrumental variables (IVs). Data on the genetic correlations between these IVs and 15 CVDs were derived from the United Kingdom (UK) Biobank, Finnish Genome Studies, and other large-scale collaborations. We conducted both univariate and multivariate MR analyses to assess the overall effects and mediated relationships after adjusting for potential confounders, including body mass index (BMI), smoking status, and type 2 diabetes. The effect sizes were estimated using inverse variance-weighted (IVW) regression.

Results

The MR analysis revealed that an increased risk of heart failure (HF) [odds ratio (OR): 1.366; 95% confidence interval (CI): 1.013-1.842; P=0.04], coronary atherosclerosis (OR: 1.918; 95% CI: 1.257-2.927; P=0.003), myocardial infarction (MI) (OR: 1.505; 95% CI: 1.025-2.211; P=0.04), and coronary artery disease (CAD) (OR: 1.519; 95% CI: 1.130-2.043; P=0.006) was significantly associated with genetically predicted daytime napping. Prolonged sleep duration was found to be related to a reduced risk of HF (OR: 0.995; 95% CI: 0.993-0.998; P=2.69E-04), peripheral vascular disease (PVD) (OR: 0.984; 95% CI: 0.971-0.997; P=0.02), and CAD (OR: 0.997; 95% CI: 0.994-0.999; P=0.006). Additionally, a statistically significant positive relationship was observed between depressive disorders and the occurrence of atrial fibrillation (AF) (OR: 1.298, 95% CI: 1.065-1.583, P=0.01), indicating a heightened susceptibility. The multivariable MR analyses substantiated the reliability of the observed associations between daytime napping and the incidence of HF and CAD, following adjustments for genetically predicted BMI and smoking. The sensitivity analysis did not reveal any evidence of horizontal pleiotropy or heterogeneity, thus supporting the validity of the study's results.

Conclusions

This MR investigation posits a potential causal nexus between daytime napping, sleep duration, and depression, and the genesis of CVDs, offering new perspectives on the prevention and management of CVDs.

No bidirectional relationship between constipation and colorectal cancer in European and Asian populations: A Mendelian randomization study

Traditional observational studies have reported a positive association between constipation and the risk of colorectal cancer (CRC). However, evidence from other approaches to pursue the causal relationship between constipation and CRC is scarce. In the study, 2-sample Mendelian randomization analysis was conducted to investigate the potential causal relationship between constipation and CRC. Analysis of the results showed that there was no causal association between constipation and CRC, either in European populations (CRC: odds ratio [OR] = 1.00, 95% confidence interval [CI] = 0.99-1.00, P = .49; rectal cancer: OR = 0.99, 95% CI = 0.99-1.00, P = .79) or in Asian populations (CRC: OR = 1.00, 95% CI = 0.99-1.01, P = .30). Also there was no inverse causal association between CRC and constipation, either in European populations (CRC: OR = 0.10, 95% CI = 2.76E-03-3.45, P = .20; rectal cancer: OR = 0.05, 95% CI = 9.14E-07-2.64E + 03, P = .59) or in Asian population (CRC: OR = 1.18, 95% CI = 0.92-1.52, P = .20), there was no horizontal diversity in the instrumental variables in the Mendelian randomization analyses of the present study (all F statistics >10), and no heterogeneity was found in the regression analyses. The findings from bidirectional 2-sample Mendelian randomization analyses indicate that there is no evidence of a bidirectional causal association between constipation and CRC. However, further investigation is warranted through additional clinical studies and trials to thoroughly explore the association between these 2 factors.

Micronutrients, Vitamin D, and Inflammatory Biomarkers in COVID-19: A Systematic Review and Meta-analysis of Causal Inference Studies

CONTEXT

Experimental and observational studies suggest that circulating micronutrients, including vitamin D (VD), may increase COVID-19 risk and its associated outcomes. Mendelian randomization (MR) studies provide valuable insight into the causal relationship between an exposure and disease outcomes.

OBJECTIVES

The aim was to conduct a systematic review and meta-analysis of causal inference studies that apply MR approaches to assess the role of these micronutrients, particularly VD, in COVID-19 risk, infection severity, and related inflammatory markers.

DATA SOURCES

Searches (up to July 2023) were conducted in 4 databases.

DATA EXTRACTION AND ANALYSIS

The quality of the studies was evaluated based on the MR-STROBE guidelines. Random-effects meta-analyses were conducted where possible.

RESULTS

There were 28 studies (2 overlapped) including 12 on micronutrients (8 on VD) and COVID-19, 4 on micronutrients (all on VD) and inflammation, and 12 on inflammatory markers and COVID-19. Some of these studies reported significant causal associations between VD or other micronutrients (vitamin C, vitamin B6, iron, zinc, copper, selenium, and magnesium) and COVID-19 outcomes. Associations in terms of causality were also nonsignificant with regard to inflammation-related markers, except for VD levels below 25 nmol/L and C-reactive protein (CRP). Some studies reported causal associations between cytokines, angiotensin-converting enzyme 2 (ACE2), and other inflammatory markers and COVID-19. Pooled MR estimates showed that VD was not significantly associated with COVID-19 outcomes, whereas ACE2 increased COVID-19 risk (MR odds ratio = 1.10; 95% CI: 1.01-1.19) but did not affect hospitalization or severity of the disease. The methodological quality of the studies was high in 13 studies, despite the majority (n = 24) utilizing 2-sample MR and evaluated pleiotropy.

CONCLUSION

MR studies exhibited diversity in their approaches but do not support a causal link between VD/micronutrients and COVID-19 outcomes. Whether inflammation mediates the VD-COVID-19 relationship remains uncertain, and highlights the need to address this aspect in future MR studies exploring micronutrient associations with COVID-19 outcomes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022328224.

Genetically predicted hypothyroidism, thyroid hormone treatment, and the risk of cardiovascular diseases: a mendelian randomization study

BACKGROUND

In this study, we explored the impact of hypothyroidism and thyroid hormone replacement therapy on the risk of developing cardiovascular diseases, including myocardial infarction, heart failure, and cardiac death, via Mendelian randomization analysis.

METHODS

Genetic instrumental variables related to hypothyroidism, levothyroxine treatment (refer to Participants were taking the medication levothyroxine sodium) and adverse cardiovascular events were obtained from a large publicly available genome-wide association study. Two-sample Mendelian randomization analysis was performed via inverse-variance weighting as the primary method. To ensure the reliability of our findings, we performed MR‒Egger regression, Cochran's Q statistic, and leave-one-out analysis. Additionally, multivariable Mendelian randomization was employed to regulate confounding factors, including systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), diabetes, cholesterol, low-density lipoprotein (LDL), triglycerides and metformin. A mediation analysis was conducted to assess the mediating effects on the association between exposure and outcome by treating atrial fibrillation and stroke as mediator variables of levothyroxine treatment and bradycardia as mediator variables of hypothyroidism.

RESULTS

Genetically predicted hypothyroidism and levothyroxine treatment were significantly associated with the risk of experiencing myocardial infarction [levothyroxine: odds ratio (OR) 3.75, 95% confidence interval (CI): 1.80-7.80; hypothyroidism: OR: 15.11, 95% CI: 2.93-77.88]. Levothyroxine treatment was also significantly related to the risk of experiencing heart failure (OR: 2.16, 95% CI: 1.21-3.88). However, no associations were detected between hypothyroidism and the risk of experiencing heart failure or between hypothyroidism or levothyroxine treatment and the risk of experiencing cardiac death. After adjusting for confounding factors, the results remained stable. Additionally, mediation analysis indicated that atrial fibrillation and stroke may serve as potential mediators in the relationships between levothyroxine treatment and the risk of experiencing heart failure or myocardial infarction.

CONCLUSION

The results of our study suggest a positive association between hypothyroidism and myocardial infarction and highlight the potential effects of levothyroxine treatment, the main thyroid hormone replacement therapy approach, on increasing the risk of experiencing myocardial infarction and heart failure.

Retinol binding protein 4 and type 2 diabetes: from insulin resistance to pancreatic β-cell function

BACKGROUND AND AIM

Retinol binding protein 4 (RBP4) is an adipokine that has been explored as a key biomarker of type 2 diabetes mellitus (T2DM) in recent years. Researchers have conducted a series of experiments to understand the interplay between RBP4 and T2DM, including its role in insulin resistance and pancreatic β-cell function. The results of these studies indicate that RBP4 has a significant influence on T2DM and is considered a potential biomarker of T2DM. However, there have also been some controversies about the relationship between RBP4 levels and T2DM. In this review, we update and summarize recent studies focused on the relationship between RBP4 and T2DM and its role in insulin resistance and pancreatic β-cell function to clarify the existing controversy and provide evidence for future studies. We also assessed the potential therapeutic applications of RBP4 in treating T2DM.

METHODS

A narrative review.

RESULTS

Overall, there were significant associations between RBP4 levels, insulin resistance, pancreatic β-cell function, and T2DM.

CONCLUSIONS

More mechanistic studies are needed to determine the role of RBP4 in the onset of T2DM, especially in terms of pancreatic β-cell function. In addition, further studies are required to evaluate the effects of drug intervention, lifestyle intervention, and bariatric surgery on RBP4 levels to control T2DM and the role of reducing RBP4 levels in improving insulin sensitivity and pancreatic β-cell function.

Causal association of basal metabolic rate on systemic sclerosis: a bidirectional mendelian randomization study

Prior evidence suggests that altered energy metabolism plays a crucial role in the development of fibrotic diseases. Recent research indicates that systemic sclerosis (SSc) patients have potentially benefited from energy management, implying that basal metabolic rate (BMR), a vital energy metabolic parameter, may be related to SSc. However, the causal effect of BMR on SSc remains unknown. Thus, we aimed to elucidate the causal links between BMR and SSc. Based on summary statistics from the genome-wide association studies (GWAS) database, two-sample Mendelian randomization (MR) was applied to explore causality between BMR and SSc. The causal relationships were assessed employing inverse variance weighted (IVW), MR-Egger, and weighted median (WM) methods. Meanwhile, several sensitivity analyses were carried out to ensure the robustness of the findings. There was an underlying genetic association of BMR on SSc (OR = 0.505, 95% CI: 0.272-0.936, P = 0.030). Moreover, no significant causal effect between SSc and BMR was observed in the reverse MR analysis (OR = 0.999, 95% CI: 0.997-1.001, P = 0.292). According to the sensitivity analysis, the presence of heterogeneity and genetic pleiotropy was not detected. Our findings, derived from a genetic perspective, provide robust evidence of a causal connection between BMR and SSc. To verify these results and clarify the potential mechanisms, further research is warranted.

Genetic insights into the association between serum cytokines and frozen shoulder risk: A bidirectional mendelian randomization study

BACKGROUND

Although existing studies have indicated a connection between chronic low-grade inflammation and the onset of frozen shoulder (FS), the precise causal relationship between distinct circulating inflammatory factors and FS has yet to be thoroughly evaluated. In this study, we employed a bidirectional two-sample Mendelian randomization (MR) analysis to investigate the potential causal relationship between systemic cytokines and FS.

METHODS

A genome-wide association dataset comprising 41 serum cytokines from 8,293 individuals of Finnish descent was utilized, along with FS data from the UK Biobank included 10,104 FS cases and 451,099 controls. The primary MR method was the inverse variance weighted approach, and four additional MR techniques (MR-Egger, weighted median, simple mode, and weighted mode) were also employed to support and validate the findings. Heterogeneity and horizontal pleiotropy assessments were assessed using Cochrane's Q and MR-Egger intercept tests. Moreover, a series of sensitivity analyses were conducted to strengthen the accuracy and credibility of these findings.

RESULTS

Based on the IVW method, genetically predicted increasing levels of growth regulated oncogene alpha (GROa) (OR=1.08, 95 % CI 1.02-1.13, P=0.005), interferon gamma-induced protein 10 (IP-10) (OR=1.09, 95 % CI 1.02-1.17, P=0.010), regulated on activation, C-C Motif Chemokine Ligand 5 (CCL5) (OR=1.11, 95 % CI 1.03-1.20, P=0.007) were suggestively associated with an increased risk of FS. Reverse MR analysis revealed no significant causal effect of FS on the 41 systemic inflammatory factors. No heterogeneity or horizontal pleiotropy was observed in our analysis.

CONCLUSION

This study established a causal association between 41 systemic inflammatory factors and FS, indicating that elevated levels of GROa, IP-10 and CCL5 were associated with a higher risk of FS. Further research is warranted to explore the potential of these biomarkers as early predictors and therapeutic targets for FS.

Blockade of mesenteric and omental adipose tissue sensory neurons improves cardiac remodeling through sympathetic pathway

Mesenteric and omental adipose tissue (MOAT) communicates directly with the heart through the secretion of bioactive molecules and indirectly through afferent signaling to the central nervous system. Myocardial infarction (MI) may induce pathological alterations in MOAT, which further affects cardiac function. Our study revealed that MI induced significant MOAT transcriptional changes in genes related with signal transduction, including adiponectin (APN), neuropeptide Y (NPY), and complement C3 (C3), potentially influencing afferent activity. We further found that MOAT sensory nerve denervation with capsaicin (CAP) prevented cardiac remodeling, improved cardiac function, and reversed cardiac sympathetic nerve hyperactivation in the MI group, accompanied by reduced serum norepinephrine. In addition, CAP reversed the elevated MOAT afferent input and brain-heart sympathetic outflow post-MI, increasing APN and NPY and decreasing C3 and serum proinflammatory factors. These results demonstrated that blockade of the MOAT afferent sensory nerve exerts a cardioprotective effect by inhibiting the brain-heart sympathetic axis.

Socioeconomic status, individual behaviors and risk for Lymphomas: a Mendelian randomization study

Background: The association of socioeconomic status and individual behavior (SES/IB) with human health is receiving increasing attention. However, the causal effects between SES/IB and lymphomas remain unclear. Methods: A two-sample Mendelian randomization (MR) study was used to assess the causal effects of 25 SES/IB traits (dietary habits, physical activity, smoking/drinking behaviors, sleeping behaviors, leisure sedentary behaviors, risky behaviors, and reproductive behaviors) on six distinct types of lymphomas, including Hodgkin lymphoma (HL), follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL), mature T/NK-cell lymphomas, marginal zone B-cell lymphoma (MZL), and mantle cell lymphoma (MCL). The inverse variance weighted (IVW) method was the primary approach used for the MR analysis. A series of sensitivity analyses were also conducted to ensure the robustness of the findings. Results: Two-sample MR revealed six SES/IB traits causally associated with lymphomas, including relative fat intake, drive time, television watching time, computer use time, vigorous physical activity, and number of children ever born. After false discovery rate (FDR) correction, the causal associations between longer television watching time and DLBCL (OR: 4.048, 95% CI: 1.688 to 9.708, P fdr=0.009), and the number of children ever born with both FL (OR: 0.008, 95% CI: 1.412E-04 to 0.484, P fdr=0.021) and DLBCL (OR: 0.001, 95% CI:1.587E-05 to 0.081, P fdr=0.002) were identified. Conclusions: These findings suggest that certain lifestyle and behavioral factors have a measurable impact on specific lymphoma types.

Potential therapeutic targets for membranous nephropathy: proteome-wide Mendelian randomization and colocalization analysis

Background

The currently available medications for treating membranous nephropathy (MN) still have unsatisfactory efficacy in inhibiting disease recurrence, slowing down its progression, and even halting the development of end-stage renal disease. There is still a need to develop novel drugs targeting MN.

Methods

We utilized summary statistics of MN from the Kiryluk Lab and obtained plasma protein data from Zheng et al. We performed a Bidirectional Mendelian randomization analysis, HEIDI test, mediation analysis, Bayesian colocalization, phenotype scanning, drug bank analysis, and protein-protein interaction network.

Results

The Mendelian randomization analysis uncovered 8 distinct proteins associated with MN after multiple false discovery rate corrections. Proteins related to an increased risk of MN in plasma include ABO [(Histo-Blood Group Abo System Transferase) (WR OR = 1.12, 95%CI:1.05-1.19, FDR=0.09, PPH4 = 0.79)], VWF [(Von Willebrand Factor) (WR OR = 1.41, 95%CI:1.16-1.72, FDR=0.02, PPH4 = 0.81)] and CD209 [(Cd209 Antigen) (WR OR = 1.19, 95%CI:1.07-1.31, FDR=0.09, PPH4 = 0.78)], and proteins that have a protective effect on MN: HRG [(Histidine-Rich Glycoprotein) (WR OR = 0.84, 95%CI:0.76-0.93, FDR=0.02, PPH4 = 0.80)], CD27 [(Cd27 Antigen) (WR OR = 0.78, 95%CI:0.68-0.90, FDR=0.02, PPH4 = 0.80)], LRPPRC [(Leucine-Rich Ppr Motif-Containing Protein, Mitochondrial) (WR OR = 0.79, 95%CI:0.69-0.91, FDR=0.09, PPH4 = 0.80)], TIMP4 [(Metalloproteinase Inhibitor 4) (WR OR = 0.67, 95%CI:0.53-0.84, FDR=0.09, PPH4 = 0.79)] and MAP2K4 [(Dual Specificity Mitogen-Activated Protein Kinase Kinase 4) (WR OR = 0.82, 95%CI:0.72-0.92, FDR=0.09, PPH4 = 0.80)]. ABO, HRG, and TIMP4 successfully passed the HEIDI test. None of these proteins exhibited a reverse causal relationship. Bayesian colocalization analysis provided evidence that all of them share variants with MN. We identified type 1 diabetes, trunk fat, and asthma as having intermediate effects in these pathways.

Conclusions

Our comprehensive analysis indicates a causal effect of ABO, CD27, VWF, HRG, CD209, LRPPRC, MAP2K4, and TIMP4 at the genetically determined circulating levels on the risk of MN. These proteins can potentially be a promising therapeutic target for the treatment of MN.

Causal relationship between dementia and delirium: Insights from a bidirectional two-sample Mendelian randomization analysis

BACKGROUND

Our previous study found dementia as a significant risk factor for delirium development in elderly patients with hip fracture. However, the causal relationship between dementia and delirium remains unclear.

METHODS

To assess the causal relationship between delirium and dementia, we conducted a bidirectional Mendelian randomization (MR) analysis. Inversevariance weighted (IVW), weighted median, MR Egger, weighted mode, and simple mode were employed to conduct the MR analysis. Heterogeneity was assessed using the Cochran Q statistic in MR-Egger and IVW methods. Horizontal pleiotropy was examined via the MR pleiotropy residual sum and outliers (MR-PRESSO) and MR-Egger intercept tests.

RESULTS

The forward MR analysis revealed a significant association between unclassified dementia (1.604 (1.326-1.941), p = 1.12 × 10-6), Alzheimer's disease (1.259 (1.128-1.405), p = 4.10 × 10-5), and dementia with Lewy bodies (1.121 (1.026-1.225), p = 0.011) with an increased risk of delirium. In the reverse MR analysis, delirium was also suggested to increase the risk of unclassified dementia (1.133 (1.066-1.204), p = 6.31 × 10-5) and vascular dementia (1.246 (1.075-1.444), p = 0.003). These significant results were further validated in the multivariable MR analysis. No evidence of heterogeneity or horizontal pleiotropy was observed (p > 0.05).

LIMITATIONS

(1) Limited to European populations. (2) Sample population overlap between delirium and dementia. (3) Not all dementia subtypes were causally associated with delirium.

CONCLUSIONS

This study provides genetic evidence supporting a causal relationship between dementia and delirium, indicating that dementia may influence the risk of delirium while delirium may also increase the risk of dementia.

No bidirectional relationship between inflammatory bowel disease and diverticular disease: a genetic correlation and Mendelian randomization study

Background: Although previous studies found that inflammatory bowel disease (IBD) and diverticular disease (DD) usually co-exist clinically, studies examining the relationship are spare. Aim: Our study aspires to investigate the causal correlation between the IBD [including ulcerative colitis (UC) and Crohn's disease (CD)] and DD using the Mendelian randomization (MR) analysis. Methods: We conducted a two-sample bidirectional MR analysis using publicly available genome-wide association studies (GWAS) summary data. The single nucleotide polymorphism (SNP) data associated with DD and IBD were obtained from the Finnish Biobank and UK Biobank, respectively. Through secondary data analysis of all GWAS summary data, we systematically screened genetic instrumental variables. To address the impact of horizontal pleiotropy, several methods were employed, including the inverse variance-weighted method (IVW), maximum likelihood method, Egger regression method, weighted median method, and simple median method. These approaches aimed to detect and correct for the potential bias caused by horizontal pleiotropy. Results: Genetically predicted DD did not have a causal effect on IBD (OR 1.06, 95% CI 0.98-1.17, p = 0.15), and had no causal effect on UC (OR 1.10, 95% CI 0.94-1.20, p = 0.36) and CD (OR 1.03, 95% CI 0.92-1.16, p = 0.62) either. Furthermore, in the reverse MR analysis, we did not observe any significant causal effect of IBD on DD. Results of complementary methods showed consistent results with those of the IVW method. Conclusion: This study's findings do not provide evidence for a causal relationship between IBD and DD, which contradicts the majority of observational studies.

Diet and risk of low back pain: a Mendelian randomization analysis

PURPOSE

Previous epidemiological and other studies have shown an association between diet and low back pain (LBP). This study aimed to investigate the causal relationship between diet and LBP using a Mendelian randomization (MR) approach.

METHODS

The three main methods in this study were weighted median, MR-Egger, and inverse variance weighting (IVW). We utilized MR-PRESSO to eliminate abnormal SNPs. Additionally, tests for pleiotropy and heterogeneity were conducted. Utilizing IVW and MR-Egger's Cochran's Q test, heterogeneity was evaluated. MR-Egger intercepts were used in pleiotropy tests. A leave-one-out analysis was also used to evaluate the stability of the study's findings.

RESULTS

The frequency of alcohol intake was associated with an increased risk of LBP. Increased processed meat intake, dried fruit intake, cereal intake, and tea intake were causally associated with a decreased risk of LBP (alcohol intake frequency: odds ratio (OR) = 1.28; 95% confidence interval (CI), 1.11-1.47; P = 0.0006; processed meat intake: OR = 0.60, 95%CI 0.39-0.92, P = 0.019; dried fruit intake: OR = 0.43, 95%CI 0.29-0.66, P = 0.00008; cereal intake: OR = 0.62, 95%CI 0.42-0.92, P = 0.018; tea intake: OR = 0.75, 95%CI 0.58-0.97, P = 0.029). Heterogeneity and pleiotropy were also not found in the sensitivity analysis. The leave-one-out analysis also showed more robust results. Other dietary intakes were not causally associated with LBP.

CONCLUSIONS

This two-sample MR study found that frequency of alcohol intake was associated with an increased risk of LBP, and intake of processed meat, dried fruit, cereals, and tea was associated with a decreased risk of LBP. Moreover, no causal relationship was found with LBP in the other 13 diets.

Causal relationship between diet and knee osteoarthritis: A Mendelian randomization analysis

BACKGROUND

Knee osteoarthritis (KOA) is a common disabling joint disease that affects millions of people worldwide. Diet may play a role in the etiology and progression of KOA, but evidence for a causal relationship is limited. We aimed to investigate the causal impact of dietary intake on KOA risk using Mendelian randomization (MR).

METHODS

We used summary-level data from genome-wide association studies (GWAS) including dietary intake (n = 335, 394-462, 342), and KOA (n = 403, 124). We selected 6-77 genetic variants as instrumental variables for 18 dietary factors, including processed meat, poultry, beef, oily fish, non-oily fish, pork, lamb, frequency of alcohol intake, alcoholic beverages, tea, coffee, dried fruit, cereals, cheese, bread, cooked vegetables, salad/raw vegetables, and fresh fruit. We performed univariate and multivariate MR analyses to estimate the causal effect of each dietary factor on KOA risk. We also performed some sensitivity analyses to assess the validity of the MR hypothesis.

RESULTS

We found that higher coffee intake was associated with increased KOA risk, whereas higher intake of dried fruits, grains, cheese, and oily fish was associated with reduced KOA risk. After multivariate adjustment, we found that coffee and oily fish intake may affect KOA through obesity, body mass index (BMI), diabetes, hypertension, and prolonged standing. Sensitivity analyses did not reveal any evidence of pleiotropy.

CONCLUSIONS

Our study provides new causal evidence that dietary intake may influence KOA risk. Specifically, we suggest that increased intake of dried fruits, grains, cheese, and oily fish and decreased coffee intake may be beneficial in preventing and mitigating KOA. further studies are needed to elucidate the underlying mechanisms and to confirm our findings in different populations.

Blood Lipid Metabolic Profiles and Causal Links to Site-Specific Cancer Risks: A Mendelian Randomization Study

Observational and Mendelian randomization (MR) studies have established links between dyslipidemia and select cancer susceptibilities. However, there is a lack of comprehensive exploration of causal relationships spanning diverse cancer types. Here, we conducted a two-sample MR analysis to elucidate the causative connections between 9 blood lipid metabolic profiles (namely, adiponectin, leptin, lipoprotein A, apolipoprotein A1, apolipoprotein B, cholesterol, triglycerides, LDL-cholesterol, and HDL-cholesterol) and 21 site-specific cancer risks. Our findings reveal genetically predicted adiponectin levels to be associated with a reduced ovarian cancer risk, while genetically determined leptin increases bladder cancer risk but decreases prostate cancer risk. Lipoprotein A elevates risk of prostate cancer while diminishing risk of endometrial cancer, while apolipoprotein A1 heightens risks of breast and cervical cancers. Furthermore, elevated levels of cholesterol are positively correlated with kidney cancer, and triglycerides demonstrate a positive association with non-melanoma skin cancer but a negative association with breast cancer. Protective effects of genetically predicted LDL-cholesterol on endometrial cancer and adverse effects of HDL-cholesterol on breast cancer are also observed. Our study conclusively establishes that blood lipid metabolic profiles exert causal effects on cancer susceptibility, providing more robust evidence for cancer prevention and prompting contemplation regarding the future health of the human populace.

Inter-organ crosstalk during development and progression of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is characterized by tissue-specific insulin resistance and pancreatic β-cell dysfunction, which result from the interplay of local abnormalities within different tissues and systemic dysregulation of tissue crosstalk. The main local mechanisms comprise metabolic (lipid) signalling, altered mitochondrial metabolism with oxidative stress, endoplasmic reticulum stress and local inflammation. While the role of endocrine dysregulation in T2DM pathogenesis is well established, other forms of inter-organ crosstalk deserve closer investigation to better understand the multifactorial transition from normoglycaemia to hyperglycaemia. This narrative Review addresses the impact of certain tissue-specific messenger systems, such as metabolites, peptides and proteins and microRNAs, their secretion patterns and possible alternative transport mechanisms, such as extracellular vesicles (exosomes). The focus is on the effects of these messengers on distant organs during the development of T2DM and progression to its complications. Starting from the adipose tissue as a major organ relevant to T2DM pathophysiology, the discussion is expanded to other key tissues, such as skeletal muscle, liver, the endocrine pancreas and the intestine. Subsequently, this Review also sheds light on the potential of multimarker panels derived from these biomarkers and related multi-omics for the prediction of risk and progression of T2DM, novel diabetes mellitus subtypes and/or endotypes and T2DM-related complications.

Rheumatoid arthritis and gastroesophageal reflux disease: a bidirectional and multivariable two-sample Mendelian randomization study

Aims/hypothesis: The association between gastroesophageal reflux disease (GERD) and rheumatoid arthritis (RA) has been reported by many observational studies in the Asian population. This study aimed to examine the bidirectional causal effects between GERD and RA by two-sample Mendelian randomization (MR) analyses using genetic evidence. Methods: Two-sample Mendelian randomization analyses were performed to determine the causal effect of GERD (129,080 cases vs. 602,604 control participants) on RA (6,236 cases vs. 147,221 control participants) and RA on GERD, respectively. The inverse-variance weighted (IVW) method was used as the primary analysis. Weighted median and MR-Egger regression were taken as supplementary analyses. Cochran's Q test evaluated the heterogeneity. Horizontal pleiotropy was detected by estimating the intercept term of MR-Egger regression. Furthermore, multivariable MR analyses were performed to exclude the influence of confounding factors, including the years of schooling, BMI, and time spent watching television, between GERD and RA. Result: Both univariate MR (UVMR) and multivariable MR (MVMR) provided valid evidence that RA was causally and positively influenced by GERD (UVMR: OR = 1.49, 95% CI = 1.25-1.76, p = 6.18*10-6; MVMR: OR = 1.69, 95% CI = 1.24-2.31, p = 8.62*10-4), whereas GERD was not influenced by RA (UVMR: OR = 1.03, 95% CI = 1.00-1.06, p = 0.042; MVMR: OR = 1.04, 95% CI = 1.00-1.07, p = 0.0271). Conclusion: Our comprehensive bidirectional MR analysis found that for the European population, GERD can induce the occurrence of RA (OR = 1.69, p < 0.00125), whereas RA only has no significant influence on GERD. In particular, patients with GERD are suffering a 69% increased risk of RA occurrence, which means GERD is a substantial risk factor for RA.

The Role of Polyunsaturated Fatty Acids in Osteoarthritis: Insights from a Mendelian Randomization Study

The prior observational research on the impact of polyunsaturated fatty acid (PUFA) supplementation on osteoarthritis (OA) patients had yielded inclusive outcomes. This study utilized the Mendelian randomization (MR) approach to explore potential causal relationships between PUFAs and OA. The MR study was performed using GWAS summary statistics for PUFAs, encompassing omega-3 and omega-6 fatty acids, and for knee OA (KOA) and hip OA (HOA). The primary inverse-variance-weighted (IVW) method and two supplementary MR approaches were used to establish robust causality. Heterogeneity and horizontal pleiotropy were assessed using Cochrane's Q and MR-Egger intercept tests. Additionally, a range of sensitivity analyses were conducted to strengthen the precision and reliability of the results. The IVW method indicated a potential genetic association between omega-3 fatty acids and KOA risk (odd ratio (OR) = 0.94, 95% confidence interval (CI): 0.89-1.00, p = 0.048). No significant correlation was found between omega-3 levels and HOA. Moreover, genetically predicted higher levels of omega-6 fatty acids were associated with a decreased risk of KOA (OR = 0. 93, 95% CI: 0.86-1.00, p = 0.041) and HOA (OR = 0.89, 95% CI: 0.82-0.96; p = 0.003). The MR-Egger intercept evaluation showed no horizontal pleiotropy affecting the MR analysis (all p  >  0.05). Our findings supported the causal relationship between PUFAs and OA susceptibility and offered a novel insight that high omega-6 fatty acids may reduce the risk of KOA and HOA. These results underscore the importance of maintaining optimal levels of PUFAs, particularly omega-6 fatty acids, in individuals with a genetic predisposition to OA. Future research is necessary to validate these findings and elucidate the underlying mechanisms involved.

Proteome-Wide Mendelian Randomization Analysis Identified Potential Drug Targets for Atrial Fibrillation

Background Finding effective and safe therapeutic drugs for atrial fibrillation (AF) is an important concern for clinicians. Proteome-wide Mendelian randomization analysis provides new ideas for finding potential drug targets. Methods and Results Using a proteome-wide Mendelian randomization approach, we assessed the genetic predictive causality between thousands of proteins and AF risk and found that genetically predicted plasma levels of phosphomevalonate kinase, tumor necrosis factor ligand superfamily member 12, sulfhydryl oxidase 2, interleukin-6 receptor subunit alpha, and low-affinity immunoglobulin gamma Fc region receptor II-b might decrease AF risk, while genetically predicted plasma levels of beta-mannosidase, collagen alpha-1(XV) chain, ANXA4 (annexin A4), COF2 (cofilin-2), and RAB1A (Ras-related protein Rab-1A) might increase AF risk (P<3.4×10-5). By using different Mendelian randomization methods and instrumental variable selection thresholds, we performed sensitivity analyses in 30 scenarios to test the robustness of positive findings. Replication analyses were also performed in independent samples to further avoid false-positive findings. Drugs targeting tumor necrosis factor ligand superfamily member 12, interleukin-6 receptor subunit alpha, low-affinity immunoglobulin gamma Fc region receptor II-b, and annexin A4 are approved or in development. The results of the phenome-wide Mendelian randomization analysis showed that changing the plasma levels of phosphomevalonate kinase, cofilin-2, annexin A4, Ras-related protein Rab-1A, sulfhydryl oxidase 2, and collagen alpha-1(XV) chain did not increase the risk of other diseases while decreasing the risk of AF. Conclusions We found a significant causal association between genetically predicted levels of 10 plasma proteins and AF risk. Four of these proteins have drugs targeting them that are approved or in development, and our results suggest the potential for these drugs to treat AF or cause AF. Sulfhydryl oxidase 2, low-affinity immunoglobulin gamma Fc region receptor II-b, and beta-mannosidase have not been suggested by previous laboratory or epidemiological studies to be associated with AF and may reveal new pathophysiological pathways as well as therapeutic targets for AF.

Valproate-Induced Metabolic Syndrome

Valproic acid (VPA) and its salts (sodium calcium magnesium and orotic) are psychotropic drugs that are widely used in neurology and psychiatry. The long-term use of VPA increases the risk of developing adverse drug reactions (ADRs), among which metabolic syndrome (MetS) plays a special role. MetS belongs to a cluster of metabolic conditions such as abdominal obesity, high blood pressure, high blood glucose, high serum triglycerides, and low serum high-density lipoprotein. Valproate-induced MetS (VPA-MetS) is a common ADR that needs an updated multidisciplinary approach to its prevention and diagnosis. In this review, we consider the results of studies of blood (serum and plasma) and the urinary biomarkers of VPA-MetS. These metabolic biomarkers may provide the key to the development of a new multidisciplinary personalized strategy for the prevention and diagnosis of VPA-MetS in patients with neurological diseases, psychiatric disorders, and addiction diseases.

Causal relationship between ischemic stroke and its subtypes and frozen shoulder: a two-sample Mendelian randomization analysis

Background

Previous epidemiological and other studies have shown an association between ischemic stroke (IS) and frozen shoulder (FS). However, the causal relationship between them remains unclear. Therefore, the present study aimed to investigate the causal relationship between IS and FS using a two-sample Mendelian randomization method.

Methods

Our research was divided into two stages: discovery and replication. The data were extracted from publicly available genome-wide association studies (GWAS). We selected a large sample of IS (n = 440, 328) and its subtypes (large-artery atherosclerotic stroke (LAS), cardioembolic stroke (CES), and stroke caused by small-vessel disease (SVS) and lacunar stroke (n = 254, 959) as exposure data. Additionally, we selected a large sample of FS as outcome data (n = 451, 099). Inverse variance weighting (IVW) was applied as the primary analysis method. The weighted median, MR-Egger, simple model, and weighted model were used as complementary analysis methods to assess causal effects. Moreover, heterogeneity was analyzed using Cochran's Q-test with IVW and MR-Egger. The MR-Egger intercept and MR-PRESSO analysis methods were used for pleiotropy testing. The stability of the results was also assessed using a leave-one-out analysis.

Results

In the discovery stage, the IVW approach revealed an odds ratio (OR) of 1.207 with a 95% confidence interval (CI) of 1.027-1.417 and a P-value of 0.022. This suggests a causal association between IS levels and an increased risk of FS. In the subtype studies of IS, the findings were negative. However, during the replication stage, a significant causal link was found between selected lacunar strokes and FS with an OR of 1.252, a 95% CI of 1.105-1.419, and a P-value of 0.0004. All studies had no pleiotropy or heterogeneity, and the findings were robust.

Conclusions

Our study confirmed the causal relationship between any IS level and increased risk of FS. Furthermore, the same results were obtained in the replication stage with lacunar stroke as an exposure factor. However, there was no direct causal relationship between the subtypes of IS and FS. Our study provides theoretical support for shoulder care for patients with IS.

The Role of Adipokines in Health and Disease

Adipokines are cell-signaling proteins secreted by adipose tissue that has been related to a low-grade state of inflammation and different pathologies. The present review aims to analyze the role of adipokines in health and disease in order to understand the important functions and effects of these cytokines. For this aim, the present review delves into the type of adipocytes and the cytokines produced, as well as their functions; the relations of adipokines in inflammation and different diseases such as cardiovascular, atherosclerosis, mental diseases, metabolic disorders, cancer, and eating behaviors; and finally, the role of microbiota, nutrition, and physical activity in adipokines is discussed. This information would allow for a better understanding of these important cytokines and their effects on body organisms.

The regulatory role of metabolic organ-secreted factors in the nonalcoholic fatty liver disease and cardiovascular disease

Nonalcoholic fatty liver disease (NAFLD) is a chronic metabolic disease characterized by an excessive accumulation of fat in the liver, which is becoming a major global health problem, affecting about a quarter of the population. In the past decade, mounting studies have found that 25%-40% of NAFLD patients have cardiovascular disease (CVD), and CVD is one of the leading causes of death in these subjects. However, it has not attracted enough awareness and emphasis from clinicians, and the underlying mechanisms of CVD in NAFLD patients remain unclear. Available research reveals that inflammation, insulin resistance, oxidative stress, and glucose and lipid metabolism disorders play indispensable roles in the pathogenesis of CVD in NAFLD. Notably, emerging evidence indicates that metabolic organ-secreted factors, including hepatokines, adipokines, cytokines, extracellular vesicles, and gut-derived factors, are also involved in the occurrence and development of metabolic disease and CVD. Nevertheless, few studies have focused on the role of metabolic organ-secreted factors in NAFLD and CVD. Therefore, in this review, we summarize the relationship between metabolic organ-secreted factors and NAFLD as well as CVD, which is beneficial for clinicians to comprehensive and detailed understanding of the association between both diseases and strengthen management to improve adverse cardiovascular prognosis and survival.

The relationship between major depression and migraine: A bidirectional two-sample Mendelian randomization study

Background

Previous epidemiological and other studies have shown an association between major depressive disorder (MDD) and migraine. However, the causal relationship between them remains unclear. Therefore, this study aimed to investigate the causal relationship between MDD and migraine using a bidirectional, two-sample Mendelian randomization (MR) approach.

Methods

Data on MDD and migraine, including subtypes with aura migraine (MA) and without aura migraine (MO), were gathered from a publicly available genome-wide association study (GWAS). Single nucleotide polymorphisms (SNPs) utilized as instrumental variables (IVs) were then screened by adjusting the intensity of the connection and removing linkage disequilibrium. To explore causal effects, inverse variance weighting (IVW) was used as the primary analysis method, with weighted median, MR-Egger, simple mode, and weighted mode used as supplementary analytic methods. Furthermore, heterogeneity and pleiotropy tests were carried out. Cochran's Q-test with IVW and MR-Egger was used to assess heterogeneity. Pleiotropy testing was carried out using the MR-Egger intercept and MR-PRESSO analysis methods. A leave-one-out analysis was also used to evaluate the stability of the findings. Finally, we used migraine (MA and MO) levels to deduce reverse causality with MDD risk.

Results

Random effects IVW results were (MDD-Migraine: odds ratio (OR), 1.606, 95% confidence interval (CI), 1.324-1.949, p = 1.52E-06; MDD-MA: OR, 1.400, 95%CI, 1.067-1.8378, p = 0.015; MDD-MO: OR, 1.814, 95%CI, 1.277-2.578, p = 0.0008), indicating a causal relationship between MDD levels and increased risk of migraine (including MA and MO). In the inverse MR analysis, the findings were all negative, while in sensitivity analyses, the results were robust except for the study of MA with MDD.

Conclusion

Our study confirms a causal relationship between MDD levels and increased risk of migraine, MA, and MO. There was little evidence in the reverse MR analysis to suggest a causal genetic relationship between migraine (MA and MO) and MDD risk levels.

Asthma and atopic dermatitis as risk factors for rheumatoid arthritis: a bidirectional mendelian randomization study

BACKGROUND

Previous observational studies have shown an association between asthma, atopic dermatitis (AD) and rheumatoid arthritis (RA). However, the bidirectional cause-effect chain between asthma and AD and RA has not been proven yet.

METHODS

We performed bidirectional two-sample Mendelian randomization (TSMR) and selected single nucleotide polymorphisms (SNPs) associated with asthma, AD, and RA as instrumental variables. All of the SNPs were obtained from the latest genome-wide association study in Europeans. Inverse variance weighted (IVW) was the main method used in MR analysis. MR-Egger, weighted model, simple model, and weighted median were used for quality control. The robustness of the results was tested by sensitivity analysis.

RESULTS

Asthma was found to be the largest effect size for RA susceptibility using the IVW method (OR, 1.35;95%CI, 1.13-1.60; P, 0.001), followed by AD (OR, 1.10;95%CI, 1.02-1.19; P, 0.019). In contrast, there was no causal relationship between RA and asthma (IVW: P = 0.673) or AD (IVW: P = 0.342). No pleiotropy or heterogeneity was found in the sensitivity analysis.

CONCLUSION

Findings from this study showed a causal relationship between genetic susceptibility to asthma or AD and increased risk of RA, but do not support a causal relationship between genetic susceptibility to RA and asthma or AD.

Constipation and cardiovascular disease: A two-sample Mendelian randomization analysis

Background

Although several observational studies have suggested positive associations between constipation and cardiovascular disease (CVD), a solid causal association has not been demonstrated. Therefore, a two-sample Mendelian randomization (MR) study was performed to investigate the causal associations between constipation and CVD.

Methods

Independent genetic variants strongly associated with constipation were obtained from the FinnGen consortium. Summary-level data for CVD, including coronary artery disease (CAD), myocardial infarction (MI), heart failure (HF), atrial fibrillation (AF), stroke, and its subtypes, were collected from a few extensive genome-wide association studies (GWASs). The inverse-variance weighted methods, weighted median, and MR-Egger were used for the MR estimates. The Cochran's Q test, MR-Egger intercept tests, MR-PRESSO, MR Steiger test, leave-one-out analyses, and funnel plot were used in the sensitivity analysis.

Results

Genetically determined constipation was suggestively associated with AF risk (odds ratio (OR), 1.07; 95% confidence interval (CI), 1.01, 1.14; p = 0.016). Constipation and other CVD do not appear to be causally related. It was demonstrated that the results were robust through sensitivity analyses.

Conclusion

This MR study demonstrated suggestive causal associations of constipation on AF, despite no associations achieving a significance value after multiple testing corrections. There was no evidence of an association between constipation and the risk of CAD, MI, HF, stroke, or stroke subtypes.

No Evidence to Support a Causal Relationship between Circulating Adiponectin Levels and Ankylosing Spondylitis: A Bidirectional Two-Sample Mendelian Randomization Study

Based on previous observational studies, the causal association between circulating adiponectin (CA) levels and ankylosing spondylitis (AS) risk remains unclear. Therefore, this study aims to investigate whether CA levels are related to the risk of AS. We carried out a bidirectional two-sample Mendelian randomization (MR) analysis to examine the causal correlation between CA levels and AS via published genome-wide association study (GWAS) datasets. Single-nucleotide polymorphisms (SNPs) related to CA levels were derived from a large GWAS that included 39,883 individuals of European descent. SNPs related to AS were obtained from the FinnGen consortium (2252 cases and 227,338 controls). The random-effects inverse variance weighted (IVW) method was the primary method utilized in our research. We also used four complementary approaches to improve the dependability of this study (MR-Egger regression, Weighted median, Weighted mode, and Simple mode). Random-effects IVW (odds ratio [OR], 1.00; 95% confidence interval [CI], 0.79-1.27, p = 0.984) and four complementary methods all indicated that genetically predicted CA levels were not causally related to the risk of AS. In reverse MR analysis, there is little evidence to support the genetic causality between the risk of AS and CA levels.

Circulating adipokine levels and preeclampsia: A bidirectional Mendelian randomization study

Background: Several observational studies have demonstrated that significantly rising circulating adipokine levels are pervasive in preeclampsia or eclampsia disorder (or preeclampsia toxemia (PET)). However, it remains unclear whether this relationship is causal. In this study, we sought to elucidate the causal effects of circulating adipokine levels on PET.

Methods: Summary-level data and independent genetic variants strongly associated with common adipokine molecule (adiponectin, leptin, resistin, sOB-R, and PAI-1) levels were drawn from public genome-wide association study (GWASs). Additionally, the corresponding effects between instrumental variables and PET outcomes were acquired from the FinnGen consortium, including 4,743 cases and 136,325 controls of European ancestry. Subsequently, an inverse-variance weighted (IVW) approach was applied for the principal two-sample Mendelian randomization (MR) and multivariable MR (MVMR) analyses. Various complementary sensitivity analyses were then carried out to determine the robustness of our models.

Results: The results of the IVW method did not reveal any causal relationship shared across genetically predisposed adipokine levels and PET risk (for adiponectin, OR = 0.86, 95% CI: 0.65–1.13, p = 0.274). Additionally, no significant associations were identified after taking into account five circulating adipokines in MVMR research. Complementary sensitivity analysis also supported no significant associations between them. In the reverse MR analysis, genetically predicted PET risk showed a suggestive association with elevating PAI-1 levels by the IVW method (Beta = 0.120, 95% CI: 0.014, 0.227, p = 0.026). Furthermore, there were no strong correlations between genetic liability to PET and other adipokine levels (p > 0.05).

Conclusion: Our MR study did not provide robust evidence supporting the causal role of common circulating adipokine levels in PET, whereas genetically predicted PET may instrumentally affect PAI-1 levels. These findings suggest that PAI-1 may be a useful biomarker for monitoring the diagnosis or therapy of PET rather than a therapeutic target for PET.