Leptinemia is Associated With Peripheral Artery Disease

Leptin in the Respiratory Tract: Is There a Role in SARS-CoV-2 Infection?

Leptin is a pleiotropic adipocytokine involved in several physiologic functions, with a known role in innate and adaptive immunity as well as in tissue homeostasis. Long- and short-isoforms of leptin receptors are widely expressed in many peripheral tissues and organs, such as the respiratory tract. Similar to leptin, microbiota affects the immune system and may interfere with lung health through the bidirectional crosstalk called the “gut-lung axis.” Obesity leads to impaired protective immunity and altered susceptibility to pulmonary infections, as those by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although it is known that leptin and microbiota link metabolism and lung health, their role within the SARS-CoV2 coronavirus disease 2019 (COVID-19) deserves further investigations. This review aimed to summarize the available evidence about: (i) the role of leptin in immune modulation; (ii) the role of gut microbiota within the gut-lung axis in modulating leptin sensitivity; and (iii) the role of leptin in the pathophysiology of COVID-19.

Obesity-Related Indices Are Associated with Peripheral Artery Occlusive Disease in Patients with Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (DM) is an increasing global health issue. Peripheral artery occlusive disease (PAOD) is a common complication of diabetes, and it is a complex and costly disease. The association between type 2 DM and obesity is well known, however, the relationship between obesity and PAOD in patients with type 2 DM has yet to be elucidated. Therefore, the aim of this study was to examine associations between obesity-related indices and PAOD in patients with type 2 DM. A total of 1872 outpatients with type 2 DM were recruited from two hospitals in southern Taiwan. An ankle–brachial index (ABI) < 0.9 in either leg was considered to indicate the presence of PAOD. The following obesity-related indices were investigated: conicity index (CI), waist–hip ratio (WHR), body roundness index (BRI), waist-to-height ratio (WHtR), abdominal volume index, a body shape index (ABSI), visceral adiposity index (VAI), lipid accumulation product (LAP), body adiposity index, body mass index and triglyceride–glucose index. Overall, 4.1% of the enrolled patients had an ABI < 0.9. High values of the following obesity-related indices were significantly associated with a low ABI: WHtR (p = 0.045), VAI (p = 0.003), CI (p = 0.042), BRI (p = 0.021) and ABSI (p = 0.043). Furthermore, WHR (area under the curve (AUC) = 0.661), CI (AUC = 0.660) and LAP (AUC = 0.642) had the best performance (all p < 0.001) to predict PAOD. In conclusion, high WHtR, BRI, CI, VAI and BAI values were associated with a low ABI in the enrolled patients, and WHR, CI and LAP were the most powerful predictors of PAOD.

Blood adipocytokine concentration in patients with peripheral artery disease

BACKGROUND

Inflammatory responses mediated by adipocytokines may affect both atherosclerosis development and progression, as well as the risk of in-stent restenosis. The aim of this study was to determine the relationships between blood leptin, adiponectin and tumor necrosis factor-α (TNF-α) concentrations and the 1-year outcome of superficial femoral artery (SFA) stenting.

METHODS

Blood concentrations of leptin, adiponectin and TNF-α were determined in 70 patients undergoing SFA stenting due to intermittent claudication and in 40 patients undergoing carotid artery stenting (CAS). All subjects were followed up for at least 1 year in relation to the occurrence of clinically driven target lesion revascularization (TLR) or a major adverse cardiovascular event (MACE).

RESULTS

Patients undergoing SFA stenting and CAS had similar blood adipocytokine concentrations. Patients with diabetes mellitus presented a higher leptin concentration, lower adiponectin-to-leptin ratio, and lower blood adiponectin concentration indexed to fat mass (FM) and to visceral adiposity score (VAS). In Kaplan-Meier analysis, blood concentration of TNF-α indexed to FM and to VAS was higher in patients who underwent TLR and MACE. However, in multifactorial analysis, the severity of atherosclerosis lesions in the femoropopliteal vascular region, estimated in relation to TASC-II classification, was the only predictor of TLR.

CONCLUSIONS

Circulating adipocytokines did not distinguish patients with different clinical manifestations of atherosclerosis. Higher ratios of TNF-α -to-FM and to VAS before SFA stenting were related to TLR and MACE occurrence. Dysregulation in adipocytokine secretion may be a potential mediator of a proatherogenic action of diabetes mellitus in patients with peripheral artery disease.

Obesity and cardiovascular disease in women

As the prevalence of obesity continues to grow worldwide, the health and financial burden of obesity-related comorbidities grows too. Cardiovascular disease (CVD) is clearly associated with increased adiposity. Importantly, women are at higher risk of CVD when obese and insulin resistant, in particular at higher risk of developing heart failure with preserved ejection fraction and ischemic heart disease. Increased aldosterone and mineralocorticoid receptor activation, aberrant estrogenic signaling and elevated levels of androgens are among some of the proposed mechanisms explaining the heightened CVD risk. In addition to traditional cardiovascular risk factors, understanding nontraditional risk factors specific to women, like excess weight gain during pregnancy, preeclampsia, gestational diabetes, and menopause are central to designing personalized interventions aimed to curb the epidemic of CVD. In the present review, we examine the available evidence supporting a differential cardiovascular impact of increased adiposity in women compared with men and the proposed pathophysiological mechanisms behind these differences. We also discuss women-specific cardiovascular risk factors associated with obesity and insulin resistance.