Update on the management of severe hypertriglyceridemia--focus on free fatty acid forms of omega-3

mTORC2 knockdown mediates lipid metabolism to alleviate hyperlipidemic pancreatitis through PPARα

Hyperlipidemic pancreatitis (HP) is an inflammatory injury of the pancreas triggered by elevated serum triglyceride (TG) levels. The mechanistic target of rapamycin (mTOR) signaling pathway plays a crucial role in regulating lipid homeostasis and inflammation. This study aimed to investigate whether the activity of mTOR complex 2 (mTORC2) affects the progression of HP and its underlying mechanisms. In vivo, a high-fat diet and retrograde administration of sodium taurocholate were employed to establish the HP models in rats, with pancreatic tissue pathology evaluated. The expression of Rictor and peroxisome proliferator-activator receptor (PPAR) was examined. The serum levels of TG, fatty acid metabolites, inflammatory and lipid metabolism-related factors were determined. In vitro, pancreatic acinar cells (PACs) were exposed to palmitic acid and cholecystokinin-8. PAC apoptosis, pyroptosis, and ferroptosis were assessed. In the HP models, rats and PACs exhibited upregulated Rictor and downregulated PPARα, and Rictor knockdown promoted PPARα expression. In vivo, Rictor knockdown decreased the serum levels of TG, α-amylase, total cholesterol, low-density lipoprotein cholesterol, lactate dehydrogenase, and inflammatory factors, while increasing high-density lipoprotein cholesterol levels. Rictor knockdown increased ACOX1 and CPT1α and decreased SREBP-1, CD36, SCD1, ACLY, and ACACA. Rictor knockdown reduced damage to pancreatic tissue structure. In vitro, Rictor knockdown inhibited PAC apoptosis, pyroptosis, and ferroptosis. Treatment with the PPARα antagonist GW6471 abolished the beneficial effects of Rictor knockdown. Rictor/mTORC2 deficiency reduces serum TG levels, maintains lipid homeostasis, and suppresses inflammation by inhibiting PPARα expression. Weakening mTORC2 activity holds promise as a novel therapeutic strategy for HP.

Efficacy and safety of omega-3-acid ethyl acetate 90 capsules in severe hypertriglyceridemia: A randomized, controlled, multicenter study

Omega-3-acid ethyl acetate 90 capsules (containing 465 mg of eicosapentaenoic acid and 375 mg docosahexaenoic acid) is composed of highly purified omega-3 polyunsaturated fatty acid (PUFA) ethyl esters, whose lipid-lowering effect for severe hypertriglyceridemia (HTG) treatment is unclear. This study aimed to evaluate the efficacy and safety of omega-3-acid ethyl acetate 90 capsules in patients with severe HTG. In this randomized, double-blind, placebo-controlled, multicenter study, 239 patients with severe HTG were enrolled and randomized (1:1) into omega-3 group (N = 122) and placebo group (N = 117) to receive 12-week corresponding treatments. Lipid-related indexes were obtained at treatment initiation (W0), 4 weeks (W4), W8, and W12 after treatment. Adverse events and adverse drug reactions were recorded. Triacylglycerols (TAG), total cholesterol (TC), non-high-density lipoprotein cholesterol (non-HDL-C), very-low-density lipoprotein cholesterol (VLDL-C), and apolipoprotein C-III (Apo C-III) at W4, W8, and W12 were decreased in the omega-3 group versus the placebo group (all p < 0.05). Moreover, the percentage changes of TAG, TC, non-HDL-C, and VLDL-C from W0 to W4, W8, and W12, and the percentage change of Apo C-III from W0 to W4 and W8, were more obvious in the omega-3 group compared with the placebo group (all p < 0.05). However, no difference was observed in the percentage changes of HDL-C, low-density lipoprotein cholesterol (LDL-C), and LDL-C/HDL-C ratio during follow-up between groups (all p > 0.05). Additionally, there was no discrepancy in adverse events and adverse drug reactions between groups (all p > 0.05). Omega-3-acid ethyl acetate 90 capsules exhibit satisfied lipid-lowering effect with tolerable safety profile in patients with severe HTG.

Synergistic anti-atherosclerotic role of combined treatment of omega-3 and co-enzyme Q10 in hypercholesterolemia-induced obese rats

Hypercholesterolemia is a metabolic disorder associated with atherosclerosis. This study aimed to investigate the effects of omega-3 and/or coenzyme Q10 (CoQ10) on hypercholesterolemia-induced atherosclerosis. Rats were divided into five groups; (1): served as the negative control, (2): served as hypercholesterolemic (HC) control, (3): HC-rats administrated omega-3 orally, (4): HC-rats administrated CoQ10 orally, and (5): HC-rats administered the combination treatment of both omega-3 and CoQ10. Lipid profile was assayed and cardiovascular risk indices were calculated. Serum levels of Adiponectin (APN) and creatine kinase (CK-MB) were determined using ELISA. Besides, oxidative stress markers, malondialdehyde (MDA), nitric oxide (NO) and glutathione (GSH) were assayed in the heart homogenate. Histopathological investigation of the aortae and heart tissues were investigated. The results revealed that atherogenic HC-rats demonstrated a significant elevation in lipid profiles, except for HDL-C, along with decreased levels of APN, but increased CK-MB activities. Hypercholesterolemia increased lipid peroxidation, reduced NO production, and decreased GSH content in the cardiac tissue. Treatment of atherogenic HC-rats with omega-3 and/or CoQ10 improved dyslipidemia and ameliorated most of the HC-induced biochemical and histopathological changes. The histological observations of aortae and cardiac tissues validated our biochemical results. We concluded that the combined treatment of nutraceuticals such as omega-3 and CoQ10 demonstrated the best outcome, demonstrating their anti-hyperlipidemic, cardioprotective, and atheroprotective potentials. Together, this study supports a beneficial role of dietary co-administration of omega-3 and CoQ10 in obese patients who are prone to develop cardiovascular disorders.

PPAR Agonists and Metabolic Syndrome: An Established Role?

Therapeutic approaches to metabolic syndrome (MetS) are numerous and may target lipoproteins, blood pressure or anthropometric indices. Peroxisome proliferator-activated receptors (PPARs) are involved in the metabolic regulation of lipid and lipoprotein levels, i.e., triglycerides (TGs), blood glucose, and abdominal adiposity. PPARs may be classified into the α, β/δ and γ subtypes. The PPAR-α agonists, mainly fibrates (including newer molecules such as pemafibrate) and omega-3 fatty acids, are powerful TG-lowering agents. They mainly affect TG catabolism and, particularly with fibrates, raise the levels of high-density lipoprotein cholesterol (HDL-C). PPAR-γ agonists, mainly glitazones, show a smaller activity on TGs but are powerful glucose-lowering agents. Newer PPAR-α/δ agonists, e.g., elafibranor, have been designed to achieve single drugs with TG-lowering and HDL-C-raising effects, in addition to the insulin-sensitizing and antihyperglycemic effects of glitazones. They also hold promise for the treatment of non-alcoholic fatty liver disease (NAFLD) which is closely associated with the MetS. The PPAR system thus offers an important hope in the management of atherogenic dyslipidemias, although concerns regarding potential adverse events such as the rise of plasma creatinine, gallstone formation, drug-drug interactions (i.e., gemfibrozil) and myopathy should also be acknowledged.

Pharmacokinetics and Oxidation Parameters in Volunteers Supplemented with Microencapsulated Docosahexaenoic Acid

Context:

Docosahexaenoic acid (DHA) is an omega-3 fatty acid essential for cardiovascular health, brain development, and reproductive function. Due to hydrophobicity and low DHA bioavailability, new microencapsulated DHA formulations are under development.

Aim:

This study aims to evaluate DHA pharmacokinetics (PKs) and biological oxidation parameters in volunteers ingesting a newly developed lutein-containing lycosomal formulation of DHA (LF-DHA).

Materials and Methods:

A total of 32 healthy volunteers (40–65 years old) with signs of oxidative stress (OS) and subclinical hypoxia were orally supplemented for a month with 250 mg of regular DHA (1^st group) or a combination of lutein (7.0 mg) and zeaxanthin (1.4 mg) (2^nd group). The third group received regular DHA (250 mg) co-ingested with lutein/zeaxanthin (7.0/1.4 mg), whereas the 4^th group was given LF-DHA containing lutein/zeaxanthin (7.0/1.4 mg). PK, OS, and oxygenation parameters were analyzed.

Results:

LF-DHA improved the PKs of DHA enhancing its serum concentrations time dependently by 34.6% and 94.1% after 2^nd and 4^th weeks, respectively. DHA and lutein ingested either alone or simultaneously as two separate formulations reduced the levels of OS markers. However, LF-DHA inhibited the malonicdialdehyde (MDA) and oxidized low-density lipoprotein values were better than other formulations. LF-DHA also enhanced the plasma oxygen and tissue oxygen saturation. This effect was significantly higher than in other groups.

Conclusion:

LF-DHA eliminates the need in high-dose DHA supplementation protocols and confers a higher DHA bioavailability, thereby improving the parameters of biological oxidation and tissue respiration in affected individuals.

A Mini-Review on the Effect of Docosahexaenoic Acid (DHA) on Cerulein-Induced and Hypertriglyceridemic Acute Pancreatitis

Acute pancreatitis refers to the sudden inflammation of the pancreas. It is associated with premature activation and release of digestive enzymes into the pancreatic interstitium and systemic circulation, resulting in pancreatic tissue autodigestion and multiple organ dysfunction, as well as with increased cytokine production, ultimately leading to deleterious local and systemic effects. Although mechanisms involved in pathogenesis of acute pancreatitis have not been completely elucidated, oxidative stress is regarded as a major risk factor. In human acute pancreatitis, lipid peroxide levels in pancreatic tissues increase. Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid (C22:6n-3), exerts anti-inflammatory and antioxidant effects on various cells. Previous studies have shown that DHA activates peroxisome proliferator-activated receptor-γ and induces catalase, which inhibits oxidative stress-mediated inflammatory signaling required for cytokine expression in experimental acute pancreatitis using cerulein. Cerulein, a cholecystokinin analog, induces intra-acinar activation of trypsinogen in the pancreas, which results in human acute pancreatitis-like symptoms. Therefore, DHA supplementation may be beneficial for preventing or inhibiting acute pancreatitis development. Since DHA reduces serum triglyceride levels, addition of DHA to lipid-lowering drugs like statins has been investigated to reduce hypertriglyceridemic acute pancreatitis. However, high DHA concentrations increase cytosolic Ca²⁺, which activates protein kinase C and may induce hyperlipidemic acute pancreatitis. In this review, effect of DHA on cerulein-induced and hypertriglyceridemic acute pancreatitis has been discussed. The relation of high concentration of DHA to hyperlipidemic acute pancreatitis has been included.

Comparative effects of plant oils and trans-fat on blood lipid profiles and ischemic stroke in rats

Since plant oils are believed to be better than animal fats for cerebrovascular and cardiovascular diseases, the effects of various plant oils and trans-fat on blood lipid profiles and ischemic stroke were investigated. Sprague-Dawley rats were fed a diet containing the oils or trans-fat, and then body weights, blood lipids, and effects on brain infarction and physical dysfunction induced by middle cerebral artery occlusion (MCAO) were analyzed. All the oils and trans-fat, except perilla oil, significantly increased body fats and body weight gain. Sesame oil and trans-fat specifically increased blood cholesterols and triglycerides, respectively, while perilla oil decreased both cholesterols and triglycerides. Perilla oil not only attenuated cerebral infarction, but also restored locomotor activity and rota-rod performances of MCAO rats. It is suggested that perilla oil among oils and fats could be the first choice to reduce the risk of metabolic syndrome and ischemic stroke.

Treatment of Hypertriglyceridemia: a Review of Current Options

Hypertriglyceridemia is an important marker of increased levels of highly atherogenic remnant-like particles. The importance of lowering plasma levels of triglycerides (TG) has been called into question many times, but currently it is considered an integral part of residual cardiovascular risk reduction strategies. Lifestyle changes (improved diet and increased physical activity) are effective TG lowering measures. Pharmacological treatment usually starts with statins, although associated TG reductions are typically modest. Fibrates are currently the drugs of choice for hyperTG, frequently in combination with statins. Niacin and omega-3 fatty acids improve control of triglyceride levels when the above measures are inadequately effective. Some novel therapies including anti-sense oligonucleotides and inhibitors of microsomal triglyceride transfer protein have shown significant TG lowering efficacy. The current approach to the management of hypertriglyceridemia is based on lifestyle changes and, usually, drug combinations (statin and fibrate and/or omega-3 fatty acids or niacin).