Statin-fibrate combination: therapy for hyperlipidemia: a review

Topical and oral peroxisome proliferator-activated receptor-α agonist ameliorates diabetic corneal neuropathy

Diabetic corneal neuropathy (DCN) is a common diabetic ocular complication with limited treatment options. In this study, we investigated the effects of topical and oral fenofibrate, a peroxisome proliferator-activated receptor-α agonist, on the amelioration of DCN using diabetic mice (n = 120). Ocular surface assessments, corneal nerve and cell imaging analysis, tear proteomics and its associated biological pathways, immuno-histochemistry and western blot on PPARα expression, were studied before and 12 weeks after treatment. At 12 weeks, PPARα expression markedly restored after topical and oral fenofibrate. Topical fenofibrate significantly improved corneal nerve fibre density (CNFD) and tortuosity coefficient. Likewise, oral fenofibrate significantly improved CNFD. Both topical and oral forms significantly improved corneal sensitivity. Additionally, topical and oral fenofibrate significantly alleviated diabetic keratopathy, with fenofibrate eye drops demonstrating earlier therapeutic effects. Both topical and oral fenofibrate significantly increased corneal β-III tubulin expression. Topical fenofibrate reduced neuroinflammation by significantly increasing the levels of nerve growth factor and substance P. It also significantly increased β-III-tubulin and reduced CDC42 mRNA expression in trigeminal ganglions. Proteomic analysis showed that neurotrophin signalling and anti-inflammation reactions were significantly up-regulated after fenofibrate treatment, whether applied topically or orally. This study concluded that both topical and oral fenofibrate ameliorate DCN, while topical fenofibrate significantly reduces neuroinflammation.

A Bayesian method to detect drug-drug interaction using external information for spontaneous reporting system

Due to the insufficiency of safety assessments of clinical trials for drugs, further assessments are required for post-marketed drugs. In addition to adverse drug reactions (ADRs) induced by one drug, drug-drug interaction (DDI)-induced ADR should also be investigated. The spontaneous reporting system (SRS) is a powerful tool for evaluating the safety of drugs continually. In this study, we propose a novel Bayesian method for detecting potential DDIs in a database collected by the SRS. By applying a power prior, the proposed method can borrow information from similar drugs for a drug assessed DDI to increase sensitivity of detection. The proposed method can also adjust the amount of the information borrowed by tuning the parameters in power prior. In the simulation study, we demonstrate the aforementioned increase in sensitivity. Depending on the scenarios, approximately 20 points of sensitivity of the proposed method increase from an existing method to a maximum. We also indicate the possibility of early detection of potential DDIs by the proposed method through analysis of the database shared by the Food and Drug Administration. In conclusion, the proposed method has a higher sensitivity and a novel criterion to detect potential DDIs early, provided similar drugs have similar observed-expected ratios to the drug under assessment.

Overcoming Resistance in Prostate Cancer Therapy Using a DZ-Simvastatin Conjugate

Prostate cancer (PC), particularly its metastatic castration-resistant form (mCRPC), is a leading cause of cancer-related deaths among men in the Western world. Traditional systemic treatments, including hormonal therapy and chemotherapy, offer limited effectiveness due to tumors' inherent resistance to these therapies. Moreover, they often come with significant side effects. We have developed a delivery method using a tumor-cell-specific heptamethine carbocyanine dye (DZ) designed to transport therapeutic agents directly to tumor cells. This research evaluated simvastatin (SIM) as the antitumor payload because of its demonstrated chemopreventive effects on human cancers and its well-documented safety profile. We designed and synthesized a DZ-SIM conjugate for tumor cell targeting. PC cell lines and xenograft tumor models were used to assess tumor-cell targeting specificity and killing activity and to investigate the corresponding mechanisms. DZ-SIM treatment effectively killed PC cells regardless of their androgen receptor status or inherent therapeutic resistance. The conjugate targeted and suppressed xenograft tumor formation without harming normal cells of the host. In cancer cells, DZ-SIM was enriched in subcellular organelles, including mitochondria, where the conjugate formed adducts with multiple proteins and caused the loss of transmembrane potential, promoting cell death. The DZ-SIM specifically targets PC cells and their mitochondria, resulting in a loss of mitochondrial function and cell death. With a unique subcellular targeting strategy, the conjugate holds the potential to outperform existing chemotherapeutic drugs. It presents a novel strategy to circumvent therapeutic resistance, offering a more potent treatment for mCRPC.

An overview on nanoplatforms for statins delivery: Perspectives for safe and effective therapy

Statins are the most widely used pharmacological agents for reducing blood cholesterol levels and treating atherosclerotic cardiovascular diseases. Most of the statins' derivatives have been limited by water solubility, bioavailability, and oral absorption, which has led to adverse effects on several organs, especially at high doses. As an approach to reducing statin intolerance, achieving a stable formulation with improved efficacy and bioavailability at low doses has been suggested. Nanotechnology-based formulations may provide a therapeutic benefit over traditional formulations in terms of potency and biosafety. Nanocarriers can provide tailored delivery platforms for statins, thereby enhancing the localized biological effects and lowering the risk of undesired side effects while boosting statin's therapeutic index. Furthermore, tailored nanoparticles can deliver the active cargo to the desired site, which culminates in reducing off-targeting and toxicity. Nanomedicine could also provide opportunities for therapeutic methods by personalized medicine. This review delves into the existing data on the potential improvement of statin therapy using nano-formulations.

Regulatory Effects and Molecular Mechanisms of Tea and Its Active Compounds on Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD), the most common chronic liver disease, is a multifactorial disease resulting from the interaction between environment, genetic background, and metabolic stress. Most treatments for NAFLD include dietary intervention and exercise show limited efficacy due to the complex mechanisms involved in NAFLD. Meanwhile, drug therapy is accompanied by serious side effects. The development of high-efficiency natural supplements is a sustainable strategy for the prevention and treatment of NAFLD. As the second most consumed beverage, tea has health benefits that have been widely recognized. Nevertheless, the intervention of tea active compounds in NAFLD has received limited attention. Tea contains abundant bioactive compounds with potential effects on NAFLD, such as catechins, flavonoids, theanine, tea pigments, and tea polysaccharides. We reviewed the intrinsic and environmental factors and pathogenic mechanisms that affect the occurrence and development of NAFLD, and summarized the influences of exercise, drugs, diet, and tea drinking on NAFLD. On this basis, we further analyzed the potential effects and molecular regulatory mechanisms of tea active compounds on NAFLD and proposed future development directions. This review hopes to provide novel insights into the development and application of tea active compounds in the prevention and treatment of NAFLD.

The Mechanism of Dendrobium officinale as a Treatment for Hyperlipidemia Based on Network Pharmacology and Experimental Validation

Aim and Objective. Hyperlipidemia is a public health matter of global scale, contributing to a wide range of diseases that can result in severe complications and significant annual mortality. Dendrobium officinale (DO) is an edible plant with a long medicinal history in China. Our previous studies revealed that DO may have therapeutic benefits in lipid disorders. However, the mechanism of its active compounds is still unclear. This research aimed at uncovering the hidden anti-hyperlipidemia mechanisms of DO through network pharmacology and experimental validation. Materials and Methods. The active compounds in DO, their targets, and targets associated with hyperlipidemia were screened across various databases, and the hidden targets of DO in treating hyperlipidemia were forecast. The compound-target (C-T), protein-protein interaction (PPI), and compound-target-pathway (C-T-P) networks of DO were set up with Cytoscape software. The hub genes and core clusters of DO predicted to be active against hyperlipidemia were calculated by Cytoscape. The DAVID database was adopted for Gene Ontology (GO) analysis and KEGG pathway enrichment analysis. Next, we used the high-sucrose-fat diet and alcohol (HFDA)-induced hyperlipidemia rats to evaluate the hypolipidemic effect of DO. Results. In this study, we obtained 264 compounds from DO, revealed 11 bioactive compounds, and predicted 89 potential targets of DO. The network analysis uncovered that naringenin, isorhamnetin, and taxifolin might be the compounds in DO that are mainly in charge of its roles in hyperlipidemia and might play a role by modulating the targets (including PPARG, ADIPOQ, AKT1, TNF, and APOB). The pathway analysis showed that DO might affect diverse signaling pathways related to the pathogenesis of hyperlipidemia, including PPAR signaling pathway, insulin resistance, AMPK signaling pathway, and non-alcoholic fatty liver disease simultaneously. Meanwhile, in the HFDA-induced hyperlipidemia rat model, DO could significantly decrease the level of TC, TG, LDL-c, and ALT in serum, and increase HDL-c as well. The liver pathological section indicated that DO could ease liver damage and lipid cumulation. Conclusion. In summary, the biological targets of the main bioactive compounds in DO were found to distribute across multiple metabolic pathways. These findings suggest that a mutual regulatory system consisting of multiple components, targets, and pathways is a likely mechanism through which DO may improve hyperlipidemia. Validation experiments indicated that DO may treat hyperlipidemia by affecting NAFLD-related signaling pathways.

A Brief Review of Cardiovascular Diseases, Associated Risk Factors and Current Treatment Regimes

Cardiovascular diseases (CVDs) are the leading cause of premature death and disability in humans and their incidence is on the rise globally. Given their substantial contribution towards the escalating costs of health care, CVDs also generate a high socio-economic burden in the general population. The underlying pathogenesis and progression associated with nearly all CVDs are predominantly of atherosclerotic origin that leads to the development of coronary artery disease, cerebrovascular disease, venous thromboembolism and, peripheral vascular disease, subsequently causing myocardial infarction, cardiac arrhythmias or stroke. The aetiological risk factors leading to the onset of CVDs are well recognized and include hyperlipidaemia, hypertension, diabetes, obesity, smoking and, lack of physical activity. They collectively represent more than 90% of the CVD risks in all epidemiological studies. Despite high fatality rate of CVDs, the identification and careful prevention of the underlying risk factors can significantly reduce the global epidemic of CVDs. Beside making favorable lifestyle modifications, primary regimes for the prevention and treatment of CVDs include lipid-lowering drugs, antihypertensives, antiplatelet and anticoagulation therapies. Despite their effectiveness, significant gaps in the treatment of CVDs remain. In this review, we discuss the epidemiology and pathology of the major CVDs that are prevalent globally. We also determine the contribution of well-recognized risk factors towards the development of CVDs and the prevention strategies. In the end, therapies for the control and treatment of CVDs are discussed.

Synthesis and Reactivity of α-Cumyl Bromodifluoromethanesulfenate: Application to the Radiosynthesis of [18 F]ArylSCF3

A highly reactive electrophilic bromodifluoromethylthiolating reagent, α-cumyl bromodifluoro-methanesulfenate 1, was prepared to allow for direct bromodifluoromethylthiolation of aryl boron reagents. This coupling reaction takes place under copper catalysis, and affords a large range of bromodifluoromethylthiolated arenes. These compounds are amenable to various transformations including halogen exchange with [18 F]KF/K222  , a process giving access to [18 F]arylSCF3 in two steps from the corresponding aryl boronic pinacol esters.

Diabetes and lipid metabolism

The authors review the association between diabetes mellitus (DM) and aberrations of lipid metabolism related to DM, diabetic dyslipidemia (DD). DM is considered as a major health burden worldwide and one of the most important modifiable cardiovascular disease (CVD) risk factors. This applies to both the developed and the developing countries, especially the latter. While patients with type 1 DM, 10% of all DM cases, usually do not have dyslipidemia, DD is frequent among patients with type 2 DM (T2DM) (prevalence > 75%) and is mainly a mixed dyslipidemia [increase in triglycerides (TGs), low high-density lipoprotein cholesterol (HDL-C), and small-dense (atherogenic), low-density lipoprotein cholesterol (LDL-C) particles]. The components of DD, which is characterized by quantitative (mentioned above), qualitative, and kinetic abnormalities all contributing to CVD risk, are mostly related to insulin resistance. Statins, ezetimibe, and PCSK9 inhibitors can be used in monotherapy or consecutively in combinations if needed. Statins compose the main drug. For the residual CVD risk after statin treatment, the use of statin-fibrate combinations is indicated only in patients with mixed dyslipidemia. In conclusion, DD is a major health problem worldwide. It is a significant CVD risk factor and should be treated according to current guidelines. The means today exist to normalize all quantitative, qualitative, and kinetic aberrations of DD, thereby reducing CVD risk.

Thyroid hormone analogs for the treatment of dyslipidemia: past, present, and future

OBJECTIVE

Treatment of dyslipidemia is a major burden for public health. Thyroid hormone regulates lipid metabolism by binding the thyroid hormone receptor (TR), but the use of thyroid hormone to treat dyslipidemia is not indicated due to its deleterious effects on heart, bone, and muscle. Thyroid hormone analogs have been conceived to selectively activate TR in the liver, thus reducing potential side-effects.

METHODS

The authors searched the PubMed database to review TR and the action of thyromimetics in vitro and in animal models. Then, all double-blind, placebo controlled trials that analyzed the use of thyroid hormone analog for the treatment of dyslipidemia in humans were included. Finally, the ongoing research on the use of TR agonists was searched, searching the US National Institutes of Health Registry and the WHO International Clinical Trial Registry Platform (ICTRP).

RESULTS

Thyromimetics were tested in humans for the treatment of dyslipidemia, as a single therapeutic agent or as an add-on therapy to the traditional lipid-lowering drugs. In most trials, thyromimetics lowered total cholesterol, low-density lipoprotein cholesterol, and triglycerides, but their use has been associated with adverse side-effects, both in pre-clinical studies and in humans.

CONCLUSIONS

The use of thyromimetics for the treatment of dyslipidemia is not presently recommended. Future possible clinical applications might include their use to promote weight reduction. Thyromimetics might also represent an interesting alternative, both for the treatment of non-alcoholic steatohepatitis, and type 2 diabetes due to their positive effects on insulin sensitivity. Finally, additional experimental and clinical studies are needed for a better comprehension of the effect(s) of a long-term therapy.

Secondary Prevention of Ischemic Cerebrovascular Disease. What Is the Evidence?

Patients who had a transient ischemic attack or stroke are at increased risk of experiencing recurrent cerebrovascular events. For this reason, secondary prevention of ischemic cerebrovascular disease is essential. Several modifiable, lifestyle-associated risk factors have been implicated, such as physical activity, smoking, and alcohol consumption. Established and emerging vascular risk factors are associated with an increased risk of stroke. Pharmacologic treatment, including the use of antiplatelet, antihypertensive, and lipid-lowering agents, has also been shown to reduce the risk of secondary cerebrovascular events. Surgical intervention, either open or endovascular, may be the preferred therapeutic option in well-defined subsets of patients. It is important to establish specific measures for the early detection and prevention of recurrent cerebrovascular disease. Therefore, further research and greater awareness in this field are needed.

Review: Fibrates: therapeutic review

As agonists of the peroxisome proliferator-activated receptor α (PPARα), fibrates are established, effective and well-tolerated agents in the management of atherogenic dyslipidaemia. Key actions of fibrates include a reduction in elevated triglyceride levels (by up to 50%) and a rise in high-density lipoprotein cholesterol (HDL-C) concentrations (typically by 5—15%). Fibrates promote a shift from small, dense low-density lipoprotein (LDL) to larger more buoyant particles, which are less susceptible to oxidation and possess higher binding affinity for removal by the non-atherogenic LDL receptor pathway. Thus, fibrates can correct lipid abnormalities commonly observed in patients with type 2 diabetes and metabolic syndrome. Clinical evidence has demonstrated the value of fibrate therapy in secondary and primary prevention settings, as well as in patients with type 2 diabetes. However, FIELD, the largest fibrate study to date in diabetic patients, predominantly in a primary prevention setting, showed a non-significant 11% reduction in the primary end point of coronary heart disease death and non-fatal myocardial infarction with fenofibrate, although total cardiovascular events, corresponding to the secondary end point, were significantly reduced by 11% (p=0.035). It is possible that risk reduction with fenofibrate may have been attenuated by the two-fold greater drop-in use of statin therapy in the placebo group. However, the interesting results of fenofibrate on attenuation of microangiographic symptomatology potentially suggest a new recommendation for fibrate therapy, although further studies are required to validate these findings.

A Systems Biology Approach for Identifying Hepatotoxicant Groups Based on Similarity in Mechanisms of Action and Chemical Structure

When evaluating compound similarity, addressing multiple sources of information to reach conclusions about common pharmaceutical and/or toxicological mechanisms of action is a crucial strategy. In this chapter, we describe a systems biology approach that incorporates analyses of hepatotoxicant data for 33 compounds from three different sources: a chemical structure similarity analysis based on the 3D Tanimoto coefficient, a chemical structure-based protein target prediction analysis, and a cross-study/cross-platform meta-analysis of in vitro and in vivo human and rat transcriptomics data derived from public resources (i.e., the diXa data warehouse). Hierarchical clustering of the outcome scores of the separate analyses did not result in a satisfactory grouping of compounds considering their known toxic mechanism as described in literature. However, a combined analysis of multiple data types may hypothetically compensate for missing or unreliable information in any of the single data types. We therefore performed an integrated clustering analysis of all three data sets using the R-based tool iClusterPlus. This indeed improved the grouping results. The compound clusters that were formed by means of iClusterPlus represent groups that show similar gene expression while simultaneously integrating a similarity in structure and protein targets, which corresponds much better with the known mechanism of action of these toxicants. Using an integrative systems biology approach may thus overcome the limitations of the separate analyses when grouping liver toxicants sharing a similar mechanism of toxicity.

Recent developments in modulating atherogenic lipoproteins

PURPOSE OF REVIEW

Randomized clinical trials have assessed the effects of several classes of drugs on plasma cholesterol levels in patients with coronary artery disease. Agents including niacin, fibrates and statins significantly lower LDL-cholesterol, but tolerance issues and undesirable side-effects are common. Residual risk may also be present in patients with persistently low HDL-cholesterol despite a reduction in LDL-cholesterol. Recent trials of drugs that increase circulating HDL-cholesterol have also been disappointing.

RECENT FINDINGS

Ongoing efforts target the development of new pharmacotherapies to reduce circulating levels of atherogenic lipoproteins. The goal of this review is to discuss recent advances in the treatment of coronary artery disease and other vascular diseases characterized by an increase in circulating atherogenic lipoproteins. These include the development of inhibitors of ATP citrate lyase and proprotein convertase subtilisin/kexin type 9. We also discuss recent developments in HDL therapy, including the clinical assessment of cholesteryl ester transfer protein inhibitors and apolipoprotein E mimetic peptides.

SUMMARY

Several new classes of drug are undergoing clinical evaluation that show promise for atherogenic lipoprotein reduction in patients who are statin intolerant.

Anti-inflammatory and cholesterol-reducing properties of apolipoprotein mimetics: a review

Reduced levels of HDL cholesterol (HDL-C) are a strong independent predictor of coronary artery disease (CAD) risk. The major anti-atherogenic function of HDL is to mediate reverse cholesterol transport. This response is highly dependent on apoA-I and apoE, protein components of HDL. Randomized clinical trials have assessed effects of several classes of drugs on plasma cholesterol levels in CAD patients. Agents including cholestyramine, fibrates, niacin, and statins significantly lower LDL cholesterol (LDL-C) and induce modest increases in HDL-C, but tolerance issues and undesirable side effects are common. Additionally, residual risk may be present in patients with persistently low HDL-C and other complications despite a reduction in LDL-C. These observations have fueled interest in the development of new pharmacotherapies that positively impact circulating lipoproteins. The goal of this review is to discuss the therapeutic potential of synthetic apolipoprotein mimetic peptides. These include apoA-I mimetic peptides that have undergone initial clinical assessment. We also discuss newer apoE mimetics that mediate the clearance of atherogenic lipids from the circulation and possess anti-inflammatory properties. One of these (AEM-28) has recently been given orphan drug status and is undergoing clinical trials.

A comprehensive review on metabolic syndrome

Metabolic syndrome is defined by a constellation of interconnected physiological, biochemical, clinical, and metabolic factors that directly increases the risk of cardiovascular disease, type 2 diabetes mellitus, and all cause mortality. Insulin resistance, visceral adiposity, atherogenic dyslipidemia, endothelial dysfunction, genetic susceptibility, elevated blood pressure, hypercoagulable state, and chronic stress are the several factors which constitute the syndrome. Chronic inflammation is known to be associated with visceral obesity and insulin resistance which is characterized by production of abnormal adipocytokines such as tumor necrosis factor α , interleukin-1 (IL-1), IL-6, leptin, and adiponectin. The interaction between components of the clinical phenotype of the syndrome with its biological phenotype (insulin resistance, dyslipidemia, etc.) contributes to the development of a proinflammatory state and further a chronic, subclinical vascular inflammation which modulates and results in atherosclerotic processes. Lifestyle modification remains the initial intervention of choice for such population. Modern lifestyle modification therapy combines specific recommendations on diet and exercise with behavioural strategies. Pharmacological treatment should be considered for those whose risk factors are not adequately reduced with lifestyle changes. This review provides summary of literature related to the syndrome's definition, epidemiology, underlying pathogenesis, and treatment approaches of each of the risk factors comprising metabolic syndrome.

Strategies to rescue steatotic livers before transplantation in clinical and experimental studies

The shortage of donor livers has led to an increased use of organs from expanded criteria donors. Included are livers with steatosis, a metabolic abnormality that increases the likelihood of graft complications post-transplantation. After a brief introduction on the etiology, pathophysiology, categories and experimental models of hepatic steatosis, we herein review the methods to rescue steatotic donor livers before transplantation applied in clinical and experimental studies. The methods span the spectrum of encouraging donor weight loss, employing drug therapy, heat shock preconditioning, ischemia preconditioning and selective anesthesia on donors, and the treatment on isolated grafts during preservation. These methods work at different stages of transplantation process, although share similar molecular mechanisms including lipid metabolism stimulation through enzymes or nuclear receptor e.g., peroxisomal proliferator-activated receptor, or anti-inflammation through suppressing cytokines e.g., tumor necrosis factor-α, or antioxidant therapies to alleviate oxidative stress. This similarity of molecular mechanisms implies possible future attempts to reinforce each approach by repeating the same treatment approach at several stages of procurement and preservation, as well as utilizing these alternative approaches in tandem.

U.K. consensus statement on safe clinical prescribing of bexarotene for patients with cutaneous T-cell lymphoma

BACKGROUND

Bexarotene is a synthetic retinoid from the subclass of retinoids called rexinoids which selectively activate retinoid X receptors. It has activity in cutaneous T-cell lymphoma (CTCL) and has been approved by the European Medicines Agency since 1999 for treatment of the skin manifestations of advanced-stage (IIB-IVB) CTCL in adult patients refractory to at least one systemic treatment. In vivo bexarotene produces primary hypothyroidism which may be managed with thyroxine replacement. It also affects lipid metabolism, typically resulting in raised triglycerides, which requires prophylactic lipid-modification therapy. Effects on neutrophils, glucose and liver function may also occur. These side-effects are dose dependent and may be controlled with corrective therapy or dose adjustments.

OBJECTIVES

  To produce a U.K. statement outlining a bexarotene dosing schedule and monitoring protocol to enable bexarotene prescribers to deliver bexarotene safely for optimal effect.

METHODS

 Leaders from U.K. supraregional centres produced this consensus statement after a series of meetings and a review of the literature.

RESULTS

 The statement outlines a bexarotene dosing schedule and monitoring protocol. This gives instructions on monitoring and treating thyroid, lipid, liver, blood count, creatine kinase, glucose and amylase abnormalities. The statement also includes algorithms for a bexarotene protocol and lipid management, which may be used in the clinical setting.

CONCLUSION

 Clinical prescribing of bexarotene for patients with CTCL requires careful monitoring to allow safe administration of bexarotene at the optimal dose.

ABCA1 mutation carriers with low high-density lipoprotein cholesterol are characterized by a larger atherosclerotic burden

AIMS

Low HDL-C is a potent risk factor for cardiovascular disease (CVD). Yet, mutations in ABCA1, a major determinant of circulating HDL-C levels, were previously not associated with CVD risk in cohort studies. To study the consequences of low plasma levels of high-density lipoprotein cholesterol (HDL-C) due to ATP-binding cassette transporter A1 (ABCA1) dysfunction for atherosclerotic vascular disease in the carotid arteries.

METHODS AND RESULTS

We performed 3.0 Tesla magnetic resonance imaging (MRI) measurements of the carotid arteries in 36 carriers of high impact functional ABCA1 mutations and 36 normolipidemic controls. Carriers presented with 42% lower HDL-C levels (P < 0.001), a larger mean wall area (18.6 ± 6.0 vs. 15.8 ± 4.3 mm(2); P = 0.02), a larger mean wall thickness (0.82 ± 0.21 vs. 0.70 ± 0.14 mm; P = 0.005), and a higher normalized wall index (0.37 ± 0.06 vs. 0.33 ± 0.04; P = 0.005) compared with controls, retaining significance after adjustment for smoking, alcohol consumption, systolic blood pressure, diabetes, body mass index, history of CVD, LDL-C, and statin use (P = 0.002).

CONCLUSION

Carriers of loss of function ABCA1 mutations display a larger atherosclerotic burden compared with age and sex-matched controls, implying a higher risk for CVD. Further studies are needed to elucidate the full function of ABCA1 in the protection against atherosclerosis. These data support the development of strategies to up-regulate ABCA1 in patients with established CVD.

Pravastatin and fenofibrate in combination (Pravafenix(®)) for the treatment of high-risk patients with mixed hyperlipidemia

Pravafenix(®) is a fixed-dose combination of pravastatin 40 mg and fenofibrate 160 mg. The rationale for the use of Pravafenix is based on the increased residual cardiovascular risk observed for high-risk patients with either increased triglycerides or low HDL cholesterol levels despite statin monotherapy. This article reviews the current available information on the pharmacology, clinical efficacy and safety of Pravafenix. Pravafenix is recommended to be taken with food in the evening. In clinical trials, Pravafenix consistently produces complementary benefits on the overall atherogenic lipid profile of high-risk patients with mixed hyperlipidemia not controlled by either pravastatin 40 mg or simvastatin 20 mg. Within the limitations of the database, Pravafenix seems to be well tolerated up to 64 weeks, with an overall tolerability and safety profile consistent with findings generally observed with fenofibrate treatment. In particular, no myopathy or rhabdomyolysis has been reported. The actual European indication is restricted to high-risk patients with mixed hyperlipidemia whose LDL cholesterol levels are adequately controlled on pravastatin 40 mg monotherapy. Whether Pravafenix confers additional cardiovascular benefits in high-risk patients treated with a statin remains to be determined.

Fibrates: therapeutic potential for diabetic nephropathy?

Despite intensive glucose-lowering treatment and advanced therapies for cardiovascular risk factors, such as hypertension and dyslipidaemia, diabetes mellitus with its macro- and microvascular complications remains a major health problem. Especially diabetic nephropathy is a leading cause of morbidity and mortality, and its prevalence is increasing. Peroxisome proliferator-activated receptor-α (PPAR-α), a member of a large nuclear receptor superfamily, is expressed in several tissues including the kidney. Recently, experimental data have suggested that PPAR-α activation plays a pivotal role in the regulation of fatty acid oxidation, lipid metabolism, inflammatory and vascular responses, and might regulate various metabolic and intracellular signalling pathways that lead to diabetic microvascular complications. This review examines the role of PPAR-α activation in diabetic nephropathy and summarises data from experimental and clinical studies on the emerging therapeutic potential of fibrates in diabetic nephropathy.

Dyslipidaemia of obesity, metabolic syndrome and type 2 diabetes mellitus: the case for residual risk reduction after statin treatment

Dyslipidaemia is frequently present in obesity, metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM). The predominant features of dyslipidaemia in these disorders include increased flux of free fatty acids (FFA), raised triglyceride (TG) and low high density lipoprotein cholesterol (HDL-C) levels, a predominance of small, dense (atherogenic) low density lipoprotein cholesterol (LDL) particles and raised apolipoprotein (apo) B values Posprandial hyperlipidaemia may also be present. Insulin resistance (IR) appears to play an important role in the pathogenesis of dyslipidaemia in obesity, MetS and T2DM. The cornerstone of treatment of this IR-related dyslipidaemia is lifestyle changes and in diabetic patients, tight glycaemic control. In addition to these measures, recent clinical trials showed benefit with statin treatment. Nevertheless, a substantial percentage of patients treated with statins still experience vascular events. This residual vascular risk needs to be addressed. This review summarizes the effects of hypolipidaemic drug combinations (including statins with cholesterol ester protein inhibitors, niacin, fibrates or fish oil, as well as fibrate-ezetimibe combination) on the residual vascular risk in patients with obesity, MetS or T2DM.

A practical approach to lipid management in the elderly

Cardiovascular disease (CVD) increases in a curvilinear fashion after 65 years in men and 75 years in women and the majority of all cardiovascular events occur in individuals older then 65 years. There are notable differences in the clinical assessment of hyperlipidaemia, cardiovascular risk estimation as well as the safety and tolerability profiles in the elderly compared to younger individuals. Clinical trial data have now demonstrated the benefits of statin treatment in the elderly in both the primary and secondary prevention settings. There is however limited data for individuals older than 80 years. Little data is available on other lipid modifying medication in the elderly. With continuing increases in average life expectancy, preventive efforts will become increasingly important for preventing morbidity, improving quality of life, and reducing healthcare expenditures for older persons. This emphasizes the importance of clinical decision-making and weighing up the risks and benefits of treatment.

Fibrates in the treatment of cardiovascular risk and atherogenic dyslipidaemia

PURPOSE

New data have emerged over the last few years about the role of fibrates in treatment of microvascular and macrovascular disease.

RECENT FINDINGS

Endpoint studies have been conducted with fibrates in coronary heart disease (CHD) since 1971 and initial results were contradictory. Fibrates later showed benefits in patients with low HDL-C and low LDL-C. The prominence ascribed to the lipid triad of the metabolic syndrome and the increasing prevalence of diabetes has increased the topicality of fibrates given their main action of converting small dense to light buoyant LDL. The Fenofibrate Intervention in Endpoint Lowering in Diabetes (FIELD) study has carried on the tradition. Fenofibrate therapy in 9795 patients comprising a mixed low-risk primary and a medium-risk secondary prevention cohort resulted in an 11% reduction in coronary events (P = 0.16), a similar but significant reduction in cardiovascular events (P = 0.04; number-needed-to-treat = 70). The benefits were concentrated in primary prevention and on nonfatal myocardial events, and post-hoc greater effects were seen in patients with moderate hypertriglyceridaemia (>2.3 mmol/l) and low HDL-C, as had previously been noted in a trial with bezafibrate. Safety was generally good, including in combination with statins, but old concerns about sudden death, pancreatitis and venous thrombosis returned. Unexpected benefits were seen with fenofibrate for microvascular endpoints including microalbuminuria and retinopathy.

SUMMARY

Fenofibrate and bezafibrate are reasonable second-line therapies for dyslipidaemia and in diabetes, and well tolerated in combination therapy. The benefits of fenofibrate for microvascular disease and its potential role in combination therapy require further confirmation.

The effect of fibrate-statin combination therapy on cardiovascular events: a retrospective cohort analysis

OBJECTIVE

To investigate the long-term efficacy of fibrate-statin combination therapy on cardiovascular events as opposed to lipid levels.

RESEARCH DESIGN AND METHODS

A retrospective analysis was performed of patients attending metabolic clinics. Cardiovascular risk factor, baseline and final lipid data and details of concomitant drug therapies were gathered on all subjects.

OUTCOME MEASURE

The occurrence of major adverse cardiovascular events (MACE) was recorded and major prognostic factors associated with outcome determined.

RESULTS

A total of 318 patients with mixed dyslipidaemia were identified on fibrate-statin therapy. Follow-up comprised an average of 7.5 years totalling 2400 patient-years. Patients were 78% male aged 62 years and 68% had evidence of previous cardiovascular disease (CVD). Smoking was present in 17%, hypertension in 41% and 32% had established diabetes. Baseline lipid parameters were total cholesterol (TC) 6.84 mmol/L, triglycerides (TG) 6.09 mmol/L and HDL-C 1.09 mmol/L. Fibrate-statin combination reduced TC by 27% to 4.64 mmol/L, TG by a median 42% to 2.33 mmol/L and increased HDL-C by 21% to 1.22 mmol/L. Non-HDL-C was reduced by 35% and apolipoprotein B by 17%. MACE occurred in 25%. Logistic regression analysis showed that patients with MACE had higher initial TC (7.02 vs. 6.80 mmol/L; p = 0.002), established CVD (65 vs. 57%; p = 0.05) and a lesser atherogenic index response (31 vs. 38%; p = 0.008). Cox regression analysis showed that age (p = 0.002), and previous CVD (p < 0.001) were determinants of outcome allied either to reduction in TG (p = 0.009), TC (p = 0.04) and increase in HDL-C (p = 0.05) or change in TG (p = 0.002) and non-HDL-C (p = 0.01).

CONCLUSION

Fibrate-statin therapy in a population with mixed dyslipidaemia resulted in an improved lipid profile with few side-effects. Consistent with its effects, decreases in TG allied with modest decrease in cholesterol and an increase in HDL-C, were associated with better prognosis.

Statin-fibrate combination for mixed dyslipidaemia: a limited option?

Abstract A growing body of evidence suggests that targeting low-density lipoprotein cholesterol is not enough and that a substantial residual risk remains despite aggressive statin treatment, particularly in patients with mixed dyslipidemia. Statin plus fibrate combination results in a more effective control of several lipid parameters than either monotherapy with a safety profile similar to both monotherapies. Therefore, this combination might represent a therapeutic option for selected patients with mixed dyslipidemia. However, the clinical benefit of statin/fibrate combination has only been observed in small subgroup analyses and more data are needed before a wider implementation is recommended in everyday clinical practice.

Fibrates: no ACCORD on their use in the treatment of dyslipidaemia

PURPOSE OF REVIEW

New data have emerged over the last few years about the role of fibrates in treatment of microvascular and macrovascular disease.

RECENT FINDINGS

Endpoint studies have been conducted with fibrates in coronary heart disease since 1971 and results have been contradictory. Fibrates have shown benefits in patients with low HDL-cholesterol and low LDL-cholesterol. Fibrates remain topical, given their actions on the lipid triad present in the metabolic syndrome and in diabetes. In the Fenofibrate Intervention in Endpoint Lowering in Diabetes study of mixed primary and secondary prevention cohorts, fenofibrate therapy resulted in an 11% reduction in coronary or cardiovascular events in monotherapy. Despite frequent use, there was little endpoint data on fibrate-statin combination therapy until recently. The Action to Control Cardiovascular Risk in Diabetes trial of fenofibrate added to baseline simvastatin therapy in diabetes showed a nonsignificant 8% reduction in cardiovascular events. The benefits were concentrated in men, and women did slightly worse with fibrate therapy. In post-hoc analysis, slight beneficial effects of fenofibrate were seen in patients with moderate hypertriglyceridaemia (>2.3 mmol/l) and low HDL-cholesterol (<0.88 mmol/l). The safety profile of fibrate-simvastatin combination was good.

SUMMARY

Fenofibrate and bezafibrate are reasonable second-line therapies for dyslipidaemia and in diabetes. They are safe in combination therapy with statins but add little endpoint benefit except possibly in patients with a significant degree of atherogenic dyslipidaemia (high triglycerides and low HDL-cholesterol). The benefits of fibrates on microvascular disease remain to be fully explored.

Association of statin use and development of renal dysfunction in type 2 diabetes--the Hong Kong Diabetes Registry

AIM

Dyslipidaemia may be a risk factor for diabetic kidney disease. We examined prospectively association between the use of statins and development of renal dysfunction in type 2 diabetes.

METHODS

A consecutive cohort of 5264 diabetic patient recruited between 1996 and 2005 underwent detailed assessments. Renal dysfunction was defined as first estimated glomerular filtration rate <60 ml/min/1.73 m(2), or, the first hospitalisation with a diagnosis of renal disease as coded by the International Classification of Disease, Ninth Revision. Drug use was quantified using the proportion of exposure time from baseline to event/death/censored time, as appropriate.

RESULTS

In this cohort (male: 47.3%, median age: 55 years, median duration of diabetes: 6.0 years), none had renal dysfunction at baseline. During a median follow-up period of 4.9 (quartiles: 2.77, 7.04) years, 703 patients (13.4%) developed renal dysfunction, 1275 patients (22.2%) were exposed to statins. After controlling for baseline risk factors, multivariable adjusted hazard ratio of statin use for development of renal dysfunction was 0.32 (95% CI 0.21-0.50, p<0.0001).

CONCLUSION

Use of statins was associated with reduced risk of developing renal dysfunction in type 2 diabetes and this association was independent of baseline risk factors.

Niacin and fibrates in atherogenic dyslipidemia: pharmacotherapy to reduce cardiovascular risk

Although statin therapy represents a cornerstone of cardiovascular disease (CVD) prevention, a major residual CVD risk (60-70% of total relative risk) remains, attributable to both modifiable and non-modifiable risk factors. Among the former, low levels of HDL-C together with elevated triglyceride (TG)-rich lipoproteins and their remnants represent major therapeutic targets. The current pandemic of obesity, metabolic syndrome, and type 2 diabetes is intimately associated with an atherogenic dyslipidemic phenotype featuring low HDL-C combined with elevated TG-rich lipoproteins and small dense LDL. In this context, there is renewed interest in pharmacotherapeutic strategies involving niacin and fibrates in monotherapy and in association with statins. This comprehensive, critical review of available data in dyslipidemic subjects indicates that niacin is more efficacious in raising HDL-C than fibrates, whereas niacin and fibrates reduce TG-rich lipoproteins and LDL comparably. Niacin is distinguished by its unique capacity to effectively lower Lp(a) levels. Several studies have demonstrated anti-atherosclerotic action for both niacin and fibrates. In contrast with statin therapy, the clinical benefit of fibrates appears limited to reduction of nonfatal myocardial infarction, whereas niacin (frequently associated with statins and/or other agents) exerts benefit across a wider range of cardiovascular endpoints in studies involving limited patient numbers. Clearly the future treatment of atherogenic dyslipidemias involving the lipid triad, as exemplified by the occurrence of the mixed dyslipidemic phenotype in metabolic syndrome, type 2 diabetes, renal, and auto-immune diseases, requires integrated pharmacotherapy targeted not only to proatherogenic particles, notably VLDL, IDL, LDL, and Lp(a), but also to atheroprotective HDL.

Fenofibrate, simvastatin and their combination in the management of dyslipidaemia in type 2 diabetic patients

OBJECTIVE

To evaluate the efficacy of fenofibrate, simvastatin or their combination in type 2 diabetic patients with combined dyslipidaemia.

RESEARCH DESIGN AND METHODS

241 patients, who had never previously taken lipid-lowering medications, received fenofibrate 145 mg/day, or simvastatin 40 mg/day, or fenofibrate 145 mg/day + simvastatin 40 mg/day combination for 12 months. We evaluated lipids, glycaemic, haemostatic, and inflammatory variables at baseline, and after 6 and 12 months.

RESULTS

After 12 months total cholesterol (TC), LDL cholesterol (LDL-C) and triglycerides (Tg) decreased while HDL cholesterol (HDL-C) increased in all groups, even if the values obtained with fenofibrate + simvastatin were the best. At the end of the study apolipoprotein A-1 (Apo A-1) increased with fenofibrate + simvastatin, while apolipoprotein B (Apo B) decreased in all groups compared to baseline. Plasminogen activator inhibitor-1 (PAI-1) and high-sensitivity C reactive protein (hs-CRP) decreased after 12 months compared to baseline with simvastatin, and with fenofibrate + simvastatin even if the value obtained with fenofibrate-simvastatin was the lowest. After 12 months, fibrinogen (Fg) decreased compared to baseline with fenofibrate + simvastatin.

LIMITATIONS

This study has some limitations. The first one is the relatively small sample of studied patients. The second one is the lack of an advanced lipid proteins evaluation, such as lipoprotein subfraction changes in the different treatment regimen. Finally, we have not selected patients that could show the best response to fibrate (i.e.: hypertriglyceridemics) or statins (i.e.: hypercholesterolemics) monotherapy, so the effect of these drugs administered alone may have been partly attenuated.

CONCLUSIONS

Fenofibrate + simvastatin association improved lipid parameters, prothrombotic and inflammatory factors, and appeared to have a good tolerability profile over 12 months of therapy.

Vasculoprotective Effects of Apolipoprotein Mimetic Peptides: An Evolving Paradigm In Hdl Therapy (Vascular Disease Prevention, In Press.)

Anti-atherogenic effects of high density lipoprotein (HDL) and its major protein component apolipoprotein A-I (apoA-I) are principally thought to be due to their ability to mediate reverse cholesterol transport. These agents also possess anti-oxidant properties that prevent the oxidative modification of low density lipoprotein (LDL) and anti-inflammatory properties that include inhibition of endothelial cell adhesion molecule expression. Results of the Framingham study revealed that a reduction in HDL levels is an independent risk factor for coronary artery disease (CAD). Accordingly, there has been considerable interest in developing new therapies that specifically elevate HDL cholesterol. However, recent evidence suggests that increasing circulating HDL cholesterol levels alone is not sufficient as a mode of HDL therapy. Rather, therapeutic approaches that increase the functional properties of HDL may be superior to simply raising the levels of HDL per se. Our laboratory has pioneered the development of synthetic, apolipoprotein mimetic peptides which are structurally and functionally similar to apoA-I but possess unique structural homology to the lipid-associating domains of apoA-I. The apoA-I mimetic peptide 4F inhibits atherogenic lesion formation in murine models of atherosclerosis. This effect is related to the ability of 4F to induce the formation of pre-β HDL particles that are enriched in apoA-I and paraoxonase. 4F also possesses anti-inflammatory and anti-oxidant properties that are independent of its effect on HDL quality per se. Recent studies suggest that 4F stimulates the expression of the antioxidant enzymes heme oxygenase and superoxide dismutase and inhibits superoxide anion formation in blood vessels of diabetic, hypercholesterolemic and sickle cell disease mice. The goal of this review is to discuss HDL-dependent and -independent mechanisms by which apoA-I mimetic peptides reduce vascular injury in experimental animal models.

Fibrates: where are we now?

Cardiovascular disease remains a leading cause of mortality worldwide. As dyslipidemia increases cardiovascular disease risk, proper management of dyslipidemia is one means by which to decrease cardiovascular disease risk. This review focuses on dyslipidemia treatment utilizing fibrate therapy, which targets high trigylcerides, low HDL, and high small, dense LDL, while contrasting fibrate therapy with statin therapy and combined therapy. Studies were obtained using electronic search strategies, such as Medline and Cochrane Library. Sources selected were limited to those that discussed fibrates, statins, and combined therapy, with specific emphasis placed on sources that focused on fibrates. Selected studies were then assessed for quality via analysis of the study's methodology, results, and data.

RESULTS

of selected studies were then stratified using a rating system devised to determine the quality of results using the scientific evidence provided for them. Combination fibrate and statin therapy can be more effective in achieving optimal lipid levels than just fibrate or statin therapy alone without significant side effects as long as gemfibrozil is not used in therapy.

Interpreting clinical trials of diabetic dyslipidaemia: new insights

Current treatment guidelines highlight the importance of aggressive lipid-modifying therapy in reducing cardiovascular risk in patients with type 2 diabetes. Statins are established as the cornerstone of dyslipidaemia management in diabetic patients, based on their efficacy in lowering levels of low-density lipoprotein cholesterol (LDL-C). However, statins fail to address the high residual cardiovascular risk in treated patients, some of which may be attributable to low HDL cholesterol (HDL-C) and elevated triglycerides and to a preponderance of small, dense LDL particles, indicating the need for further intervention. Fibrates are effective against all components of atherogenic dyslipidaemia associated with type 2 diabetes. Clinical studies, most notably the Fenofibrate Intervention and Event Lowering in Diabetes, indicate that fibrates, most likely in combination with a statin, have a secondary role in reducing cardiovascular risk in patients with type 2 diabetes, particularly in those without prior cardiovascular disease or patients with low HDL-C. Results are awaited from the ongoing Action to Control Cardiovascular Risk in Diabetes trial to fully evaluate the outcome benefits of this combination strategy.

Update on the clinical utility of fenofibrate in mixed dyslipidemias: mechanisms of action and rational prescribing

Mixed dyslipidemia is a common lipid disorder characterized by the presence of an atherogenic lipoprotein phenotype due to abnormalities in various atherogenic and anti-atherogenic lipoproteins. Despite the link between the decrease of LDL-cholesterol by statin treatment and the prevention of cardiovascular disease, a high residual risk is observed in statin trials. This residual risk is partly explained by lipoprotein abnormalities other than LDL. Fenofibrate exerts a favorable effect on the atherogenic lipid profile of mixed dyslipidemia and can effectively reduce cardiovascular disease in patients with mixed dyslipidemia. Fenofibrate may offer important treatment alternatives as a second-line therapy in several circumstances: in combination with a statin for patients with mixed dyslipidemias not at goals on statin mono-therapy; in monotherapy for patients intolerant or with contraindication to statin therapy; and in combination with other drugs (ezetimibe, colesevelam) for patients with mixed dyslipidemias, known intolerance, or contraindication to statin and not at goals on fenofibrate monotherapy. However, the role of fenofibrate-statin therapy and of other therapies involving fenofibrate in cardiovascular risk reduction strategies remains to be established.

HDL therapy for cardiovascular diseases: the road to HDL mimetics

3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are currently the drug of choice for the clinical management of elevated low-density lipoprotein (LDL) cholesterol. Although statin treatment provides an overall improvement in outcomes, clinical trial data reveal a significant number of cardiac events despite reaching targeted LDL levels. A low serum high-density lipoprotein (HDL) cholesterol level is an independent predictor of cardiovascular risk. Accordingly, there has been interest in determining whether HDL elevation, in addition to LDL lowering, further reduces risk in patients with coronary artery disease. Several commonly prescribed lipid-lowering therapies modestly raise HDL, but their use may be limited by the development of adverse reactions. Emerging data suggest that HDL quality and function may also be significantly reduced by atherosclerosis and other inflammatory diseases. The goal of this review is to discuss the current status of HDL therapeutics, with emphasis on a novel class of agent, the apolipoprotein A-I mimetic peptides, which improve the functional properties of HDL cholesterol.

Management of lipids in the prevention of cardiovascular events

Lipid-modifying therapy has been proven to significantly reduce cardiovascular events and total mortality. Most of the data have come from statin trials. Statin therapy is generally well-tolerated and safe, and for patients who are at higher than average risk of cardiovascular disease, the benefit of lipid-modifying therapy far exceeds the risk. Careful risk assessment is a critical component of effective lipid-modifying therapy. In the foreseeable future, low-density lipoprotein cholesterol (LDL-C) will remain the primary therapeutic target, and combination therapy is likely to become the norm. The major questions are how low to treat and how to achieve increasingly aggressive targets in lipid-lowering therapy. Many patients on LDL-lowering therapy continue to have abnormalities of the triglyceride-high-density lipoprotein (TG-HDL) axis, so additional drug therapy is often considered for such patients. In this review, we briefly discuss new developments in cardiovascular risk assessment, then discuss recent developments in treatment to reduce LDL, and finally discuss current concepts regarding therapy targeting the TG-HDL axis.

Endothelial function, arterial stiffness and lipid lowering drugs

The endothelium is a dynamic organ that plays a pivotal role in cardiovascular homeostasis. Alteration in endothelial function precedes the development of atherosclerosis and contributes to its initiation, perpetuation and clinical manifestations. It has been suggested that the assessment of endothelial function could represent a barometer of vascular health that could be used to gauge cardiovascular risk. This review summarises the various methods used to assess endothelium-dependent vasodilatation and their potential prognostic implications. In addition, the techniques used to evaluate arterial stiffness are discussed. The latter is to some extent controlled by the endothelium and has been the subject of considerable research in recent years. This paper also discusses the effects of lipid lowering treatment on both endothelial function and arterial stiffness.