Chiara Macchi

Nutraceutical approach to moderate cardiometabolic risk: results of a randomized, double-blind and crossover study with Armolipid Plus.

BACKGROUND Primary cardiovascular prevention may be achieved by lifestyle/nutrition improvements and specific drugs, although a relevant role is now emerging for specific functional foods and nutraceuticals. OBJECTIVES The aim of this study was to evaluate the usefulness of a nutraceutical multitarget approach in subjects with moderate cardiovascular risk and to compare it with pravastatin treatment. SUBJECTS Thirty patients with moderate dyslipidemia and metabolic syndrome (according to the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults) were included in an 8-week randomized, double-blind crossover study and took either placebo or a nutraceutical combination that contained red yeast rice extract, berberine, policosanol, astaxanthin, coenzyme Q10, and folic acid (Armolipid Plus). Subsequently, they were subjected to another 8-week treatment with pravastatin 10 mg/d. This dosage was selected on the basis of its expected -20% efficacy in reducing low-density lipoprotein-cholesterol. RESULTS Treatment with Armolipid Plus led to a significant reduction of total cholesterol (-12.8%) and low-density lipoprotein-cholesterol (-21.1%), similar to pravastatin (-16% and -22.6%, respectively), and an increase of high-density lipoprotein-cholesterol (4.8%). Armolipid Plus improved the leptin-to-adiponectin ratio, whereas adiponectin levels were unchanged. CONCLUSIONS These results indicate that this nutraceutical approach shows a lipid-lowering activity comparable to pravastatin treatment. Hence, it may be a safe and useful option, especially in conditions of moderate cardiovascular risk, in which a pharmacologic intervention may not be appropriate.

Suppressor of Cytokine Signaling-3 (SOCS-3) Induces Proprotein Convertase Subtilisin Kexin Type 9 (PCSK9) Expression in Hepatic HepG2 Cell Line

The suppressor of cytokine signaling (SOCS) proteins are negative regulators of the JAK/STAT pathway activated by proinflammatory cytokines, including the tumor necrosis factor-α (TNF-α). SOCS3 is also implicated in hypertriglyceridemia associated to insulin resistance. Proprotein convertase subtilisin kexin type 9 (PCSK9) levels are frequently found to be positively correlated to insulin resistance and plasma very low density lipoprotein (VLDL) triglycerides concentrations. The present study aimed to investigate the possible role of TNF-α and JAK/STAT pathway on de novo lipogenesis and PCSK9 expression in HepG2 cells. TNF-α induced both SOCS3 and PCSK9 in a concentration-dependent manner. This effect was inhibited by transfection with siRNA anti-STAT3, suggesting the involvement of the JAK/STAT pathway. Retroviral overexpression of SOCS3 in HepG2 cells (HepG2SOCS3) strongly inhibited STAT3 phosphorylation and induced PCSK9 mRNA and protein, with no effect on its promoter activity and mRNA stability. Consistently, siRNA anti-SOCS3 reduced PCSK9 mRNA levels, whereas an opposite effect was observed with siRNA anti-STAT3. In addition, HepG2SOCS3 express higher mRNA levels of key enzymes involved in the de novo lipogenesis, such as fattyacid synthase, stearoyl-CoA desaturase (SCD)-1, and apoB. These responses were associated with a significant increase of SCD-1 protein, activation of sterol regulatory element-binding protein-1c (SREBP-1), accumulation of cellular triglycerides, and secretion of apoB. HepG2SOCS3 show lower phosphorylation levels of insulin receptor substrate 1 (IRS-1) Tyr896 and Akt Ser473 in response to insulin. Finally, insulin stimulation produced an additive effect with SOCS3 overexpression, further inducing PCSK9, SREBP-1, fatty acid synthase, and apoB mRNA. In conclusion, our data candidate PCSK9 as a gene involved in lipid metabolism regulated by proinflammatory cytokine TNF-α in a SOCS3-dependent manner.

Statin therapy and related risk of new-onset type 2 diabetes mellitus

The use of statins for cardiovascular disease (CVD) prevention is clearly supported by clinical evidence. Although statin therapy is rather well tolerated, recent data from prospective and retrospective clinical trials and related meta-analyses suggest an increased incidence of new-onset type 2 diabetes mellitus (T2DM) in association with such treatment. The incidence of this adverse effect is not negligible, especially for specific subsets of patients, such as women, elderly, presence of familial history of T2DM and Asian ethnicity. Statin-driven T2DM appears to be a medication class-effect, mostly not related to potency nor to individual statin, as well as to be independent of previous history of CVD. Therefore, implementation of strategies for identification of patients using statins and at specific risk of incident T2DM, as well as of different therapeutic options is important and is discussed in this article. As most authors emphasized that benefits of CVD reduction by statin therapy seem to far exceed the risk of T2DM development itself, these medications remain the cornerstone for primary and secondary CVD prevention, although a specific attention to glucose metabolism and metabolic syndrome features should be payed before and during statin treatment, especially in cohorts at greater risk.

Low-intermediate dose testosterone replacement therapy by different pharmaceutical preparations improves frailty score in elderly hypogonadal hyperglycaemic patients

Abstract An open-label follow-up study of low-to-intermediate dose testosterone replacement therapy (TRT) was conducted in 64 overweight patients (aged 65–75 years) with late onset hypogonadism (LOH) and increased fasting plasma glucose (FPG). Patients were subdivided into four treatment groups: oral testosterone (T) (T undecanoate, 80 mg/d), transmucosal T (60 mg/d), transdermal T (30 mg/d) or no treatment (control), and evaluated at 0 and 6 months. FPG, hemoglobin (Hb), prostate-specific antigen (PSA) and total T were measured and the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) index was calculated. Body mass index (BMI), waist circumference, fitness level (6-min walking test), Aging Males’ Symptoms (AMS) scale, handgrip strength and energy expenditure with physical activity (Minnesota questionnaire for Leisure Time Physical Activity (LTPA)) were evaluated and a “frailty score” (based on: grip strength, gait speed and LTPA) was calculated. T levels increased in all treatment groups; the oral T group had values still in the hypogonadal range (5.9 ± 1.1 nmol/L). PSA and Hb concentrations did not change in any group. BMI, waist circumference, FPG and HOMA-IR improved in all T-treated groups after 6 months, with a greater effect seen with transmucosal and transdermal T compared with oral T. This study indicates that low-to-intermediate dose TRT may be safely utilized in LOH patients to ameliorate somatic and psychological frailty symptoms in association with improved anthropometric and glycometabolic parameters in aging, overweight men with LOH and impaired fasting glucose.

Proprotein convertase subtilisin kexin type 9 and high-density lipoprotein metabolism: experimental animal models and clinical evidence

Proprotein convertase subtilisin kexin type 9 (PCSK9) belongs to the proprotein convertase family. Several studies have demonstrated its involvement in the regulation of low-density lipoprotein (LDL) cholesterol levels by inducing the degradation of the LDL receptor (LDLR). However, experimental, epidemiologic, and pharmacologic data provide important evidence on the role of PCSK9 also on high-density lipoproteins (HDLs). In mice, PCSK9 regulates the HDL cholesterol (HDL-C) levels by the degradation of hepatic LDLR, thus inhibiting the uptake of apolipoprotein (Apo)E-containing HDLs. Several epidemiologic and genetic studies reported positive relationship between PCSK9 and HDL-C levels, likely by reducing the uptake of the ApoE-containing HDL particles. PCSK9 enhances also the degradation of LDLRs closest family members, ApoE receptor 2, very low-density lipoprotein receptor, and LDLR-related protein 1. This feature provides a molecular mechanism by which PCSK9 may affect HDL metabolism. Experimental studies demonstrated that PCSK9 directly interacts with HDL by modulating PCSK9 self-assembly and its binding to the LDLR. Finally, the inhibition of PCSK9 by means of monoclonal antibodies directed to PCSK9 (ie, evolocumab and alirocumab) determines an increase of HDL-C fraction by 7% and 4.2%, respectively. Thus, the understanding of the role of PCSK9 on HDL metabolism needs to be elucidated with a particular focus on the effect of PCSK9 on HDL-mediated reverse cholesterol transport.

Liver fat accumulation is associated with circulating PCSK9

Abstract Background: Nonalcoholic fatty liver disease (NAFLD) associates with cardiovascular disease independently of classic risk factors. Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) is secreted by hepatocytes and inhibits the uptake of low-density lipoproteins by targeting the receptor for degradation, and possibly lipogenesis. PCSK9 loss-of-function mutations and anti-PCKS9 drugs reduce LDL-cholesterol. Aim: To evaluate whether hepatic fat content is associated with circulating PCSK9. Materials and methods: In 201 consecutive patients biopsied for suspected nonalcoholic steatohepatitis, liver damage was quantified by NAFLD activity score, circulating PCSK9 by ELISA, and hepatic mRNA by qRT-PCR in a subset (n = 76). Results: Circulating PCSK9 was associated with steatosis grade (p = 0.0011), necroinflammation (p < 0.001), ballooning (p = 0.005), and fibrosis stage (p = 0.001). At multivariate analysis, PCSK9 was associated with steatosis grade (p = 0.012), older age and lower BMI, independently of sex, hyperglycemia, and fibrosis/inflammation. Circulating PCSK9 was associated with hepatic expression of SREBP-1c (p = 0.0002) and FAS (p = 0.03). PCSK9 mRNA levels were also correlated with steatosis severity (p = 0.04) and hepatic APOB (p < 0.001), SREBP-1c (p = 0.047) and FAS expression (p = 0.001). Conclusions: Circulating PCSK9 increases with hepatic fat accumulation and correlates with the severity of steatosis, independently of metabolic confounders and liver damage. Modulation of PCSK9 synthesis and release might be involved in NAFLD pathogenesis. Key Messages Circulating PCSK9 levels increase with hepatic fat accumulation. Circulating PCSK9 levels are associated with increased de novo lipogenesis. Hepatic PCSK9 expression is associated with steatosis severity and activation of lipogenesis.

Hepatic steatosis and PNPLA3 I148M variant are associated with serum Fetuin-A independently of insulin resistance

Fetuin‐A is a liver‐derived peptide associated with insulin resistance. Aim of this cross‐sectional study was to evaluate whether Fetuin‐A is increased in patients with nonalcoholic fatty liver disease (NAFLD) vs. healthy subjects without metabolic abnormalities and the association with insulin resistance and liver damage. To investigate the causal relationship between fatty liver and Fetuin‐A, we also analysed whether the inherited I148M PNPLA3 variant modulates Fetuin‐A.

Free and bound plasma leptin in anorexia nervosa patients during a refeeding program

Anorexia nervosa (AN) has a complex pathophysiology, involving heterogeneous environmental and genetic factors, and is not associated to validated biomarkers for diagnosis and follow-up or outcome. Although the evaluation of changes of plasma biochemical markers, such as reproductive and thyroid hormones, adipokines and ghrelin, in AN may reflect the disnutritional condition rather than specific features of the disease [1], the combination of eating disorder and amenorrhea led to hypothesize the involvement of leptin or leptin-related mechanisms in the pathophysiology and the maintenance of this psychiatric syndrome [2, 3]. In AN patients, serum leptin levels are lower than in age-matched controls [4] and increase upon weight gain, together with a reduction of soluble leptin receptor [5]. The present study was aimed at evaluating the changes of plasma leptin in its free (FL) and soluble receptor-bound (BL) fractions and their relationship with body weight gain in AN patients undergoing a refeeding/ rehabilitation program. Materials and methods

PCSK9 induces a pro-inflammatory response in macrophages

Intraplaque release of inflammatory cytokines from macrophages is implicated in atherogenesis by inducing the proliferation and migration of media smooth muscle cells (SMCs). PCSK9 is present and released by SMCs within the atherosclerotic plaque but its function is still unknown. In the present study, we tested the hypothesis that PCSK9 could elicit a pro-inflammatory effect on macrophages. THP-1-derived macrophages and human primary macrophages were exposed to different concentrations (0.250 ÷ 2.5 µg/ml) of human recombinant PCSK9 (hPCSK9). After 24 h incubation with 2.5 µg/ml PCSK9, a significant induction of IL-1β, IL-6, TNF-α, CXCL2, and MCP1 mRNA, were observed in both cell types. Co-culture of THP-1 macrophages with HepG2 overexpressing hPCSK9 also showed the induction of TNF-α (2.4 ± 0.5 fold) and IL-1β (8.6 ± 1.8 fold) mRNA in macrophages. The effect of hPCSK9 on TNF-α mRNA in murine LDLR−/− bone marrow macrophages (BMM) was significantly impaired as compared to wild-type BMM (4.3 ± 1.6 fold vs 31.1 ± 6.1 fold for LDLR−/− and LDLR+/+, respectively). Finally, a positive correlation between PCSK9 and TNF-α plasma levels of healthy adult subjects (males 533, females 537) was observed (B = 8.73, 95%CI 7.54 ÷ 9.93, p < 0.001). Taken together, the present study provides evidence of a pro-inflammatory action of PCSK9 on macrophages, mainly dependent by the LDLR.

Osteocalcin as a potential risk biomarker for cardiovascular and metabolic diseases.

Abstract Clear evidence supports a role for circulating and locally-produced osteocalcin (OC) in the pathophysiology of cardiovascular (CV) lesions and CV risk, also in combination with metabolic changes, including type 2 diabetes mellitus (T2DM). Reduced plasma OC levels are associated with greater incidence of pathological CV changes, like arterial and valvular calcification, coronary and carotid atherosclerosis and increased carotid intima-media thickness. The actual relationship between OC levels and incidence of major CV events is, however, still unclear. Moreover, reduced circulating OC levels have been mostly associated with insulin resistance, metabolic syndrome or T2DM, indicating relevant OC actions on pancreatic β-cells and insulin secretion and activity. Based on these observations, this review article will attempt to summarize the current evidence on the potential usefulness of circulating OC as a biomarker for CV and metabolic risk, also evaluating the currently open issues in this area of research.