Liver-specific adiponectin gene therapy suppresses microglial NLRP3-inflammasome activation for treating Alzheimer's disease.

Adiponectin (APN) is an adipokine which predominantly expresses in adipocytes with neuroprotective and anti-inflammatory effects. We have recently indicated that circulatory trimeric APN can enter the brain by crossing the blood-brain barrier (BBB) and modulate microglia-mediated neuroinflammation. Here, we found that the microglial NLR family pyrin domain containing 3 (NLRP3)-inflammasome activation was exacerbated in APN-/-5xFAD mice in age-dependent manner. The focus of this study was to develop a new and tractable therapeutic approach for treating Alzheimer's disease (AD)-related pathology in 5xFAD mice using peripheral APN gene therapy. We have generated and transduced adeno-associated virus (AAV2/8) expressing the mouse mutated APN gene (APNC39S) into the liver of 5xFAD mice that generated only low-molecular-weight trimeric APN (APNTri). Single dose of AAV2/8-APNC39S in the liver increased circulatory and cerebral APN levels indicating the overexpressed APNTri was able to cross the BBB. Overexpression of APNTri decreased both the soluble and fibrillar Aß in the brains of 5xFAD mice. AAV2/8-APNTri treatment reduced Aß-induced IL-1ß and IL-18 secretion by suppressing microglial NLRP3-inflammasome activation. The memory functions improved significantly in AAV-APNTri-treated 5xFAD mice with reduction of dystrophic neurites. These findings demonstrate that peripheral gene delivery to overexpress trimeric APN can be a potential therapy for AD.

SGLT2i reduces risk of developing HCC in patients with co-existing type 2 diabetes and hepatitis B infection: A territory-wide cohort study in Hong Kong.

BACKGROUND AND AIMS: Type 2 diabetes (T2D) and chronic hepatitis B infection (CHB) are risk factors of HCC. Sodium glucose co-transporter 2 inhibitors (SGLT2i) inhibit HCC oncogenesis in preclinical studies. However, clinical studies are lacking. This study aimed to evaluate the impact of SGLT2i use on incident HCC using a territory-wide cohort of exclusively patients with co-existing T2D and CHB. APPROACH AND RESULTS: Patients with co-existing T2D and CHB between 2015 and 2020 were identified from the representative electronic database of the Hong Kong Hospital Authority. Patients with and without SGLT2i use were 1:1 matched by propensity score for their demographics, biochemistry results, liver-related characteristics, and background medications. Cox proportional hazards regression model was used to assess the association between SGLT2i use and incident HCC. A total of 2,000 patients with co-existing T2D and CHB (1,000 in each SGLT2i and non-SGLT2i group; 79.7% on anti-HBV therapy at baseline) were included after propensity-score matching. Over a follow-up of 3,704 person-years, the incidence rates of HCC were 1.39 and 2.52 cases per 100 person-year in SGLT2i and non-SGLT2i groups, respectively. SGLT2i use was associated with a significantly lower risk of incident HCC (HR 0.54, 95%CI: 0.33-0.88, p =0.013). The association remained similar regardless of sex, age, glycemic control, diabetes duration, presence of cirrhosis and hepatic steatosis, timing of anti-HBV therapy, and background antidiabetic agents including dipeptidyl peptidase-4 inhibitors, insulin, or glitazones (all p interaction>0.05). CONCLUSIONS: Among patients with co-existing T2D and CHB, SGLT2i use was associated with a lower risk of incident HCC.

Serum thrombospondin-2 level changes with liver stiffness improvement in patients with type 2 diabetes.

OBJECTIVE: Baseline circulating thrombospondin-2 (TSP2) level was identified as a potential novel hepatic fibrosis biomarker that associates with development and progression of hepatic fibrosis in patients with nonalcoholic fatty liver disease and type 2 diabetes. Here, we investigated whether circulating TSP2 levels changed with improvement in liver stiffness (LS), which reflects liver fibrosis on transient elastography. DESIGN: Serum TSP2 levels were measured in participants from a randomized, open-label intervention study, at baseline and after 24-weeks treatment of either dapagliflozin 10 mg (N = 30) or sitagliptin 100 mg daily (N = 30). Vibration-controlled transient elastography was performed to evaluate the severity of hepatic fibrosis and steatosis using LS and controlled attenuation parameter (CAP), respectively. PATIENTS AND MEASUREMENTS: Among all 60 participants with similar clinical characteristics at baseline (mean HbA1c 8.9%, CAP 289 dB/m and LS 5.8 kPa), despite similar HbA1c lowering, treatment with dapagliflozin, but not sitagliptin, led to significant improvements in body weight (BW) (p = .012), CAP (p = .015) and LS (p = .011) after 24 weeks. RESULTS: Serum TSP2 level decreased significantly from baseline in dapagliflozin-treated participants (p = .035), whereas no significant change was observed with sitagliptin. In correlation analysis, change in serum TSP2 levels only positively correlated with change in LS (r = .487, p = .006), but not with changes in BW, CAP or HbA1c after dapagliflozin treatment. CONCLUSIONS: Serum TSP2 level decreased with LS after dapagliflozin treatment, and was independent of improvements in BW, glycemic control and hepatic steatosis, further supporting the potential of serum TSP2 level as a novel hepatic fibrosis biomarker in type 2 diabetes.

Advanced glycation end-products and its soluble receptor are not independent predictors of incident dysglycaemia or metabolic syndrome in women with polycystic ovary syndrome: a prospective observational study.

BACKGROUND: To evaluate the association of serum advanced glycation end-products (AGEs) and its soluble receptor of AGE (sRAGE) levels with dysglycaemia and metabolic syndrome in women with polycystic ovary syndrome (PCOS). METHODS: This was an analysis of a cohort of women with PCOS who were prospectively recruited for a longitudinal observational study on their endocrine and metabolic profile between January 2010 and December 2013. The association of serum AGEs and sRAGE levels with dysglycaemia and metabolic syndrome at the second-year visit (the index visit) and the sixth-year visit (the outcome visit) were determined. Comparisons of continuous variables between groups were made using the Mann-Whitney U-test. Spearman test was used for correlation analysis. Multivariate binary logistic regression analysis was employed to identify the factors independently associated with the outcome events. RESULTS: A total of 329 women were analysed at the index visit. Significantly lower serum levels of sRAGE (both p < 0.001), but no significant difference in AGEs, were observed in those with dysglycaemia or metabolic syndrome. At the outcome visit, those with incident metabolic syndrome had a significantly lower initial serum sRAGE levels (p = 0.008). The association of serum sRAGE with dysglycaemia and metabolic syndrome at the index visit was no longer significant in multivariate logistic regression after controlling for body mass index, free androgen index and homeostatic model assessment for insulin resistance (HOMA-IR). sRAGE was also not significantly associated with incident metabolic syndrome at the outcome visit on multivariate logistic regression. CONCLUSIONS: Serum sRAGE levels are significantly lower in women with PCOS who have dysglycaemia or metabolic syndrome, and in those developing incident metabolic syndrome in four years. However, it does not have a significant independent association with these outcome measures after adjusting for body mass index, free androgen index and HOMA-IR.

Circulating thrombospondin-2 level for identifying individuals with rapidly declining kidney function trajectory in type 2 diabetes: a prospective study of the Hong Kong West Diabetes Registry.

BACKGROUND: Thrombospondin-2 (TSP2) is a matricellular protein with tissue expression induced by hyperglycaemia. TSP2 has been implicated in non-diabetic renal injury in preclinical studies and high circulating levels were associated with worse kidney function in cross-sectional clinical studies. Therefore, we investigated the prospective associations of circulating TSP2 level with kidney function decline and the trajectories of estimated glomerular filtration rate (eGFR) in type 2 diabetes. METHODS: Baseline serum TSP2 level was measured in 5471 patients with type 2 diabetes to evaluate its association with incident eGFR decline, defined as ≥ 40% sustained eGFR decline, using multivariable Cox regression analysis. Among participants with relatively preserved kidney function (Baseline eGFR ≥ 60 ml/min/1.73m2), joint latent class modelling was employed to identify three different eGFR trajectories. Their associations with baseline serum TSP2 was evaluated using multinomial logistic regression analysis. The predictive performance of serum TSP2 level was examined using time-dependent c-statistics and calibration statistics. RESULTS: Over a median follow-up of 8.8 years, 1083 patients (19.8%) developed eGFR decline. Baseline serum TSP2 level was independently associated with incident eGFR decline (HR 1.21, 95%CI 1.07-1.37, P = 0.002). With internal validation, incorporating serum TSP2 to a model of clinical risk factors including albuminuria led to significant improvement in c-statistics from 83.9 to 84.4 (P < 0.001). Among patients with eGFR ≥ 60 ml/min/1.73m2, baseline serum TSP2 level was independently associated with a rapidly declining eGFR trajectory (HR 1.63, 95%CI 1.26-2.10, P < 0.001). CONCLUSION: Serum TSP2 level was independently associated with incident eGFR decline, particularly a rapidly declining trajectory, in type 2 diabetes.

A polygenic risk score improves risk stratification of coronary artery disease: a large-scale prospective Chinese cohort study.

AIMS: To construct a polygenic risk score (PRS) for coronary artery disease (CAD) and comprehensively evaluate its potential in clinical utility for primary prevention in Chinese populations. METHODS AND RESULTS: Using meta-analytic approach and large genome-wide association results for CAD and CAD-related traits in East Asians, a PRS comprising 540 genetic variants was developed in a training set of 2800 patients with CAD and 2055 controls, and was further assessed for risk stratification for CAD integrating with the guideline-recommended clinical risk score in large prospective cohorts comprising 41 271 individuals. During a mean follow-up of 13.0 years, 1303 incident CAD cases were identified. Individuals with high PRS (the highest 20%) had about three-fold higher risk of CAD than the lowest 20% (hazard ratio 2.91, 95% confidence interval 2.43-3.49), with the lifetime risk of 15.9 and 5.8%, respectively. The addition of PRS to the clinical risk score yielded a modest yet significant improvement in C-statistic (1%) and net reclassification improvement (3.5%). We observed significant gradients in both 10-year and lifetime risk of CAD according to the PRS within each clinical risk strata. Particularly, when integrating high PRS, intermediate clinical risk individuals with uncertain clinical decision for intervention would reach the risk levels (10-year of 4.6 vs. 4.8%, lifetime of 17.9 vs. 16.6%) of high clinical risk individuals with intermediate (20-80%) PRS. CONCLUSION: The PRS could stratify individuals into different trajectories of CAD risk, and further refine risk stratification for CAD within each clinical risk strata, demonstrating a great potential to identify high-risk individuals for targeted intervention in clinical utility.

Chronic oral administration of adipoRon reverses cognitive impairments and ameliorates neuropathology in an Alzheimer's disease mouse model.

Circulating adiponectin (APN) levels decrease with age and obesity. On the other hand, a reduction in APN levels is associated with neurodegeneration and neuroinflammation. We previously showed that aged adiponectin knockout (APN-/-) mice developed Alzheimer's like pathologies, cerebral insulin resistance, and cognitive impairments. More recently, we also demonstrated that APN deficiency increased Aß-induced microglia activation and neuroinflammatory responses in 5xFAD mice. There is compelling evidence that deregulated insulin activities or cerebral insulin resistance contributes to neuroinflammation and Alzheimer's disease (AD) pathogenesis. Here, we demonstrated that APN levels were reduced in the brain of AD patients and 5xFAD mice. We crossbred 5xFAD mice with APN-/- mice to generate APN-deficient 5xFAD (5xFAD;APN-/-). APN deficiency in 5xFAD mice accelerated amyloid loading, increased cerebral amyloid angiopathy, and reduced insulin-signaling activities. Pharmacokinetics study demonstrated adipoRon (APN receptor agonist) was a blood-brain barrier penetrant. AdipoRon improved neuronal insulin-signaling activities and insulin sensitivity in vitro and in vivo. Chronic adipoRon treatment improved spatial memory functions and significantly rescued neuronal and synaptic loss in 5xFAD and 5xFAD;APN-/- mice. AdipoRon lowered plaque and Aß levels in AD mice. AdipoRon also exerted anti-inflammatory effects by reducing microglial and astrocytes activation as well as suppressing cerebral cytokines levels. The microglial phagocytic activity toward Aß was restored after adipoRon treatment. Our results indicated that adipoRon exerts multiple beneficial effects providing important therapeutic implications. We propose chronic adipoRon administration as a potential treatment for AD.

Mendelian Randomization Focused Analysis of Vitamin D on the Secondary Prevention of Ischemic Stroke.

BACKGROUND AND PURPOSE: Experimental studies showed vitamin D (Vit-D) could promote vascular regeneration and repair. Prior randomized studies had focused mainly on primary prevention. Whether Vit-D protects against ischemic stroke and myocardial infarction recurrence among subjects with prior ischemic insults was unknown. Here, we dissected through Mendelian randomization any effect of Vit-D on the secondary prevention of recurrent ischemic stroke and myocardial infarction. METHODS: Based on a genetic risk score for Vit-D constructed from a derivation cohort sample (n=5331, 45% Vit-D deficient, 89% genotyped) via high-throughput exome-chip screening of 12 prior genome-wide association study-identified genetic variants of Vit-D mechanistic pathways (rs2060793, rs4588, and rs7041; F statistic, 73; P<0.001), we performed a focused analysis on prospective recurrence of myocardial infarction (MI) and ischemic stroke in an independent subsample with established ischemic disease (n=441, all with prior first ischemic event; follow-up duration, 41.6±14.3 years) under a 2-sample, individual-data, prospective Mendelian randomization approach. RESULTS: In the ischemic disease subsample, 11.1% (n=49/441) had developed recurrent ischemic stroke or MI and 13.3% (n=58/441) had developed recurrent or de novo ischemic stroke/MI. Kaplan-Meier analyses showed that genetic risk score predicted improved event-free survival from recurrent ischemic stroke or MI (log-rank, 13.0; P=0.001). Cox regression revealed that genetic risk score independently predicted reduced risk of recurrent ischemic stroke or MI combined (hazards ratio, 0.62 [95% CI, 0.48-0.81]; P<0.001), after adjusted for potential confounders. Mendelian randomization supported that Vit-D is causally protective against the primary end points of recurrent ischemic stroke or MI (Wald estimate: odds ratio, 0.55 [95% CI, 0.35-0.81]) and any recurrent or de novo ischemic stroke/MI (odds ratio, 0.64 [95% CI, 0.42-0.91]) and recurrent MI alone (odds ratio, 0.52 [95% CI, 0.30-0.81]). CONCLUSIONS: Genetically predicted lowering in Vit-D level is causal for the recurrence of ischemic vascular events in persons with prior ischemic stroke or MI.

Role of non-thyroidal illness syndrome in predicting adverse outcomes in COVID-19 patients predominantly of mild-to-moderate severity.

OBJECTIVE: Existing studies reported the potential prognostic role of non-thyroidal illness syndrome (NTIS), characterized by low triiodothyronine (T3) with normal/low thyroid-stimulating hormone (TSH), mainly in severe COVID-19. None considered the significant impact of SARS-CoV-2 viral load on adverse outcomes. We aimed to clarify the prognostic role of NTIS among predominantly mild-to-moderate COVID-19 patients. DESIGN: A prospective study of COVID-19 patients. PATIENTS AND MEASUREMENTS: Consecutive adults admitted to Queen Mary Hospital for confirmed COVID-19 from July to December 2020 were prospectively recruited. SARS-CoV-2 viral load was represented by cycle threshold (Ct) values from real-time reverse transcription-polymerase chain reaction of the respiratory specimen on admission. Serum TSH, free thyroxine and free T3 were measured on admission. The outcome was deterioration in clinical severity, defined as worsening in ≥1 category of clinical severity according to the Chinese National Health Commission guideline. RESULTS: We recruited 367 patients. At baseline, 75.2% had mild disease, and 27 patients (7.4%) had NTIS. Fifty-three patients (14.4%) had clinical deterioration. Patients with NTIS were older, had more comorbidities, worse symptomatology, higher SARS-CoV-2 viral loads and worse profiles of inflammatory and tissue injury markers. They were more likely to have clinical deterioration (p < .001). In multivariable stepwise logistic regression analysis, NTIS independently predicted clinical deterioration (adjusted odds ratio 3.19, p = .017), in addition to Ct value <25 (p < .001), elevated C-reactive protein (p = .004), age >50 years (p = .011) and elevated creatine kinase (p = .017). CONCLUSIONS: Non-thyroidal illness syndrome was not uncommon even in mild-to-moderate COVID-19 patients. NTIS on admission could predict clinical deterioration in COVID-19, independent of SARS-CoV-2 viral load, age and markers of inflammation and tissue injury.

Thyroid Immune-Related Adverse Events in Patients with Cancer Treated with anti-PD1/anti-CTLA4 Immune Checkpoint Inhibitor Combination: Clinical Course and Outcomes.

OBJECTIVE: Thyroid immune-related adverse events (irAEs) have been reported to have prognostic significance among patients with cancer treated with anti-programmed cell death-1 (PD1) and anti-programmed death-ligand 1 monotherapies. We evaluated the clinical course and predictors of thyroid irAEs in relation to outcomes of patients with advanced cancer treated with combination anti-PD1/anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA4). METHODS: We conducted a regional study and identified patients with advanced cancer who received ≥1 cycle of combination anti-PD1/anti-CTLA4 between 2015 and 2019 in Hong Kong. Thyroid function tests (TFTs) were monitored every 3 weeks. Thyroid irAE was defined by ≥2 abnormal TFTs after initiation of combination anti-PD1/anti-CTLA4 in the absence of other causes. RESULTS: One hundred and three patients were included (median age: 59 years; 71.8% men). About 45% had prior anti-PD1 exposure. Upon median follow-up of 6.8 months, 17 patients (16.5%) developed thyroid irAEs, where 6 initially presented with thyrotoxicosis (overt, n = 4; subclinical, n = 2) and 11 with hypothyroidism (overt, n = 2; subclinical, n = 9). Eventually, 10 patients (58.8%) required continuous thyroxine replacement. Systemic steroid was not required in all cases. Prior anti-PD1 exposure (odds ratio, 3.67; 95% CI, 1.19-11.4; P = .024) independently predicted thyroid irAEs. Multivariable Cox regression analysis revealed that occurrence of thyroid irAEs was independently associated with better overall survival (adjusted hazard ratio, 0.34; 95% CI, 0.17-0.71; P = .004). CONCLUSION: Thyroid irAEs are common in routine clinical practice among patients with advanced cancer treated with anti-PD1/anti-CTLA4 combination and might have potential prognostic significance. Regular TFT monitoring is advised for timely treatment of thyroid irAEs to prevent potential morbidities.

Long COVID in Patients With Mild to Moderate Disease: Do Thyroid Function and Autoimmunity Play a Role?

OBJECTIVE: Post-acute sequelae of coronavirus disease 2019 (COVID-19) or long COVID (LC) is an emerging global health issue. Fatigue is a common feature. Whether thyroid function and autoimmunity play a role is uncertain. We aimed to evaluate the prevalence and predictors of LC and the potential role of thyroid function and autoimmunity in LC. METHODS: We included consecutive adults without a known thyroid disorder who were admitted to a major COVID-19 center for confirmed COVID-19 from July to December 2020. Thyroid function tests and antithyroid antibodies were measured for all patients on admission and at follow-up. LC was defined by the presence or persistence of symptoms upon follow-up. RESULTS: In total, 204 patients (median age, 55.0 years; 95 men [46.6%]) were reassessed at a median of 89 days (interquartile range, 69-99) after acute COVID-19. Of the 204 patients, 41 (20.1%) had LC. Female sex (adjusted odds ratio, 2.48; P = .018) and severe acute respiratory syndrome coronavirus 2 polymerase chain reaction cycle threshold value of <25 on admission (adjusted odds ratio, 2.84; P = .012) independently predicted the occurrence of LC. Upon follow-up, most abnormal thyroid function tests in acute COVID-19 resolved, and incident thyroid dysfunction was rare. Nonetheless, we observed incident antithyroid peroxidase (anti-TPO) positivity. Although baseline or follow-up thyroid function tests were not associated with the occurrence of LC, among 172 patients with symptomatic acute COVID-19, symptom resolution was more likely in those with positive anti-TPO upon follow-up (P = .043). CONCLUSION: LC is common among COVID-19 survivors, with females and those with higher viral load in acute COVID-19 particularly being vulnerable. The observation of incident anti-TPO positivity warrants further follow-up for thyroid dysfunction. Whether anti-TPO plays a protective role in LC remains to be elucidated.

Association of adipokines with hepatic steatosis and fibrosis in chronic hepatitis B patients on long-term nucleoside analogue.

BACKGROUND & AIMS: It is unknown how concomitant hepatic steatosis affects disease progression in chronic hepatitis B (CHB). Adipokines such as fibroblast growth factor 21 (FGF21) and adipocyte fatty acid-binding protein (AFABP) have been associated with non-alcoholic fatty liver disease. We determined the significance of these metabolic markers in CHB-related liver injury. METHODS: We recruited CHB patients on antiviral treatment for transient elastography assessment to determine liver stiffness (advanced fibrosis/cirrhosis, F3/F4, defined by EASL-ALEH criteria) and controlled attenuation parameter (hepatic steatosis, defined as ≥ 248 dB/m). Plasma FGF-21, AFABP and adiponectin levels were measured. RESULTS: A total of 415 patients [mean age 59.6 years, 71.6% male, median treatment duration 6.2 years] were recruited. Patients with F3/F4 (N = 151) had lower FGF-21 (11.7 vs 13.6 pg/mL, P = 0.055), higher AFABP (126.8 vs 84.1 pg/mL, P < 0.001) and HOMA-IR (7.1 vs 5.1, P = 0.004) levels compared to those without F3/F4 (N = 264). Multivariate analysis showed that FGF-21 level was associated with hepatic steatosis (OR 1.005, 95% CI 1.001-1.009) and F3/F4 (OR 0.993, 95% CI 0.989-0.998), while AFABP level (OR 1.001, 95% CI 1-1.002), body mass index (BMI) (OR 1.107, 95% CI 1.037-1.182) and presence of diabetes mellitus (OR 2.059, 95% CI 1.206-3.516) were associated with F3/F4. With the combined presence of BMI ≥ 25 kg/m2 , diabetes and AFABP > 105.9 pg/mL, the odds ratio for F3/F4 was 3.712 (95% CI 1.364-10.105, P = 0.010). CONCLUSIONS: Low FGF-21 and high AFABP levels were associated with advanced fibrosis/cirrhosis in CHB patients on antiviral treatment. Plasma AFABP, together with other metabolic risk factors, may aid identification of patients lacking fibrosis improvement during antiviral treatment.

Independent association of serum vitamin D with anti-Mullerian hormone levels in women with polycystic ovary syndrome.

OBJECTIVE: This study aimed at investigating the association of serum vitamin D (25(OH)D) and anti-Mullerian hormone (AMH) levels in women with polycystic ovary syndrome (PCOS) as well as non-PCOS healthy ovulatory women and the possible confounding effects of adiposity and androgen. METHOD: This was a cross-sectional study conducted on serum samples collected from 451 women diagnosed with PCOS as well as 244 age-matched healthy ovulatory women in a tertiary gynaecology out-patient clinic and a family planning clinic. RESULTS: Serum 25(OH)D level was significantly higher in women recruited during summer and autumn than those recruited in winter and spring. Both serum 25(OH)D and AMH levels peaked during summer in women with PCOS. In ovulatory women, only serum 25(OH)D but not AMH level showed such seasonal variation. Serum 25(OH)D level in women with PCOS significantly correlated positively with AMH, AMH/antral follicle count (AFC) ratio, serum total testosterone, sex-hormone-binding globulin and quantitative insulin-sensitivity check index and inversely with body mass index (BMI), insulin, triglycerides and homeostatic model assessment of insulin resistance. After controlling for BMI, 25(OH)D level remained significantly correlated positively with serum AMH, AMH/AFC and total testosterone, and inversely with triglycerides. 25(OH)D level was an independent predictor of serum AMH level after controlling for age, BMI and free androgen index in women with PCOS. CONCLUSION: Serum 25(OH)D level is an independent factor significantly associated with AMH level in women with PCOS but not in ovulatory women.

Genetically deprived vitamin D exposure predisposes to atrial fibrillation.

AIMS: Low vitamin D level is associated with atrial fibrillation (AF) and may be implicated in its pathogenesis. METHODS AND RESULTS: We studied single nucleotide polymorphisms (SNPs) of vitamin D mechanistic pathways and serum 25-hydroxyvitamin D [25(OH)D] levels in an age- and gender-matched case-control study (controls without AF: mean age 68.6 ± 8.7 years, female 25%; n = 1019; with AF: mean age 69.7 ± 9.5 years, female 30%; n = 156) recruited from a Chinese clinical cohort of patients with stable coronary artery disease. Twelve SNPs involved in the vitamin D mechanistic pathways were studied [biosynthetic: rs4646536, rs10877012, rs3829251, rs1790349; activation: rs2060793, rs1993116; vitamin D-binding protein (VBP)/group-specific component (GC): rs4588, rs7041, rs2282679, rs1155563; and vitamin D receptor: rs1544410, rs10735810]. A genetic risk score (GRS) (0-8) was constructed from SNPs associated with serum 25(OH)D as a proxy to lifelong vitamin D-deficient state. All 4 SNPs involved in the VBP/GC were significantly associated with serum 25(OH)D (rs4588, P < 0.001; rs2282679, P < 0.001; rs7041, P = 0.011; rs1155563, P < 0.001; all other SNPs, P > 0.05). Vitamin D GRS (points 0-8) generated from these 4 SNPs was independently predictive of serum 25(OH)D [B = 0.54, 95% confidence interval (CI) 0.30-0.79; P < 0.001]. Genetically deprived vitamin D status as denoted by a low GRS (0-3) independently predicted an increased risk of AF, compared to a high GRS (4-8) (odds ratio = 1.848, 95% CI 1.217-2.805; P = 0.004). CONCLUSION: Genetically deprived vitamin D exposure predisposes to increased AF among patients with coronary artery disease. Whether VBP/GC may alter the risk of AF via alternative mechanisms warrants further studies.

CPAP therapy for patients with sleep apnea and type 2 diabetes mellitus improves control of blood pressure.

PURPOSE: Obstructive sleep apnea (OSA) is highly associated with type 2 diabetes mellitus (DM), and treatment of OSA may have a positive impact on cardiometabolic profile. This study investigates the effects of continuous positive airway pressure (CPAP) treatment on glycemic control and cardiometabolic parameters in patients with diabetes. METHODS: Diabetic patients, who were newly diagnosed of OSA with an apnea hypopnea index (AHI) ≥15 and HbA1c ≥7%, were randomly assigned to either CPAP treatment or no treatment (control) for 3 months. Measurements included HbA1c, blood pressure, fasting glucose and lipids, urinary albumin, and peripheral arterial tonometry (to assess endothelial function). RESULTS: Sixty-four patients (52 men) were randomized, with mean (±SD) age of 55.0 ± 9.6 years, body mass index of 29.9 ± 5.3 kg/m2, HbA1c of 8.1 ± 1.1%, and AHI of 45.3 ± 23.2 events/h. In the intention-to-treat analysis, no significant change in HbA1c but reduction of systolic (10 mmHg (-18 to -2), p < 0.05) and diastolic (6 mmHg (-11 to -1), p < 0.05) blood pressures were found in the CPAP group compared to the control group. Excluding those with medication changes or initiated dietary program during the study period and those who dropped out, CPAP treatment decreased HbA1c (intervention group, n = 27; control group, n = 26) by 0.4% (-0.7 to -0.1), p = 0.027. CONCLUSIONS: In patients with type 2 DM and moderate to severe OSA, 3 months of CPAP therapy did not decrease HbA1c but lowered systolic and diastolic blood pressures. In view of a potentially limited effect size of CPAP treatment on glycemic control, sample size estimation for future randomized controlled studies must make adequate allowance for influence from external factors of medications/diet and CPAP use.

Incremental prognostic value of global longitudinal strain in patients with type 2 diabetes mellitus.

BACKGROUND: Patients with type 2 diabetes mellitus (T2DM) are at high risk for cardiovascular events. The aim of the study was to assess whether global longitudinal strain (GLS) provides prognostic value in these patients. METHODS: A total of 247 T2DM patients without history of cardiovascular complications and participated in the CDATS study were prospectively enrolled. Left ventricular (LV) systolic function was assessed by LV ejection fraction and speckle tracking derived LV systolic GLS. Diastolic function was assessed by E/E' ratio defined as the passive trans-mitral LV inflow velocity to tissue Doppler imaging velocity of the medial mitral annulus. Cardiovascular event included acute coronary syndrome, cerebrovascular stroke, hospitalization for heart failure and cardiovascular death. RESULTS: A total of 18 cardiovascular events occurred during a median follow-up duration of 33 months. Both E/E' ratio [hazard ratio (HR) 1.15, P < 0.01] and GLS (HR 1.39, P < 0.01) were independently associated with cardiovascular events. Importantly, GLS provided incremental prognostic information in addition to clinical data, HbA1c and E/E' ratio (Chi square 77.46, P = 0.04). Receiver-operator characteristic curve analysis demonstrated that E/E' ratio [area under curve (AUC) 0.66, P = 0.03] and GLS (AUC 0.72, P < 0.01) were strong predictors of cardiovascular events. Kaplan-Meier analysis showed that patients with E/E' > 13.6 or GLS > -17.9 % were associated with cardiovascular events. The presence of either a high E/E' ratio or an impaired GLS provides an excellent negative predictive value of cardiovascular events in these patients. CONCLUSIONS: In T2DM patients with no history of cardiovascular disease, impaired GLS was associated with cardiovascular events and provided incremental prognostic value.

Serum adiponectin is independently associated with the metabolic syndrome in Hong Kong, Chinese women with polycystic ovary syndrome.

OBJECTIVE: To evaluate the association of serum adiponectin level with the metabolic syndrome in Chinese women with polycystic ovary syndrome (PCOS). METHODS: This was a cross-sectional study carried out in Hong Kong Chinese women with PCOS at a university-affiliated tertiary hospital between January 2010 and January 2011. Clinical and biochemical parameters of the women were analysed. Prediction of the metabolic syndrome was determined by receiver-operator characteristic (ROC) curves, univariate and multivariate logistic regression analyses. RESULTS: A total of 116 women diagnosed to have PCOS were analysed. The area under the ROC curve of adiponectin for the prediction of metabolic syndrome was 0.820, 95% confidence interval (CI) 0.737-0.886. Univariate binary logistic regression showed that testosterone, sex hormone-binding globulin (SHBG), free androgen index (FAI), waist circumference, body mass index (BMI), quantitative insulin-sensitivity check index (QUICKI), homeostasis model assessment of insulin resistance (HOMA-IR) and adiponectin were significantly associated with the metabolic syndrome. On multivariate logistic regression analysis, adiponectin (p = 0.020), HOMA-IR, age (p = 0.011) and BMI (p = 0.019) were independently associated with the metabolic syndrome, but not FAI (p = 0.256). CONCLUSIONS: Serum adiponectin is independently associated with the metabolic syndrome in Chinese women with PCOS. Further longitudinal follow-up studies are needed to determine whether serum adiponectin adds to the prediction of long-term cardiometabolic morbidity conferred by age, BMI and measures of insulin resistance.

Adropin is a brain membrane-bound protein regulating physical activity via the NB-3/Notch signaling pathway in mice.

Adropin is a highly conserved polypeptide that has been suggested to act as an endocrine factor that plays important roles in metabolic regulation, insulin sensitivity, and endothelial functions. However, in this study, we provide evidence demonstrating that adropin is a plasma membrane protein expressed abundantly in the brain. Using a yeast two-hybrid screening approach, we identified NB-3/Contactin 6, a brain-specific, non-canonical, membrane-tethered Notch1 ligand, as an interaction partner of adropin. Furthermore, this interaction promotes NB3-induced activation of Notch signaling and the expression of Notch target genes. We also generated and characterized adropin knockout mice to explore the role of adropin in vivo. Adropin knockout mice exhibited decreased locomotor activity and impaired motor coordination coupled with defective synapse formation, a phenotype similar to NB-3 knockout mice. Taken together, our data suggest that adropin is a membrane-bound protein that interacts with the brain-specific Notch1 ligand NB3. It regulates physical activity and motor coordination via the NB-3/Notch signaling pathway and plays an important role in cerebellum development in mice.

Altered myocardial response in patients with diabetic retinopathy: an exercise echocardiography study.

BACKGROUND: Type 2 diabetes mellitus (T2DM) complicated by retinopathy is associated with altered left ventricular (LV) structure and resting myocardial dysfunction unlike T2DM without retinopathy. The myocardial response to stress has not been compared in patients with and without diabetic retinopathy. The aim of this retrospective study was to determine the relationship between retinopathy and myocardial function in patients with T2DM at rest and during exercise echocardiography. METHODS: 134 patients with T2DM and no evidence of underlying coronary artery disease were recruited. All patients underwent retinal photography to screen for diabetic retinopathy, and resting and exercise echocardiography. Resting echocardiography was analyzed by conventional echocardiographic parameters and speckle tracking derived global longitudinal strain (GLS). Exercise echocardiography parameters included diastolic function reserve index (DFRI) and stress GLS. RESULTS: The mean age of participants was 60 years and 49% were male. Diabetic retinopathy was identified in 43 patients (32%). Resting echocardiography revealed that those with diabetic retinopathy had a higher prevalence of impaired diastolic function, higher E/E' ratio (LV filling pressures) and impaired resting GLS compared with those without. Exercise echocardiography revealed that those with diabetic retinopathy also had more impaired DFRI and stress GLS. Multivariable analysis showed that the presence of diabetic retinopathy was independently associated with high resting E/E', diastolic dysfunction grade, impaired resting GLS, low DFRI and impaired stress GLS. CONCLUSIONS: In conclusion, the presence of diabetic retinopathy was independently associated with impaired resting myocardial function (diastolic and systolic function) and myocardial function during stress (evaluated by DFRI and stress GLS).