Isoborneol Attenuates Low-Density Lipoprotein Accumulation and Foam Cell Formation in Macrophages

Advances and perspectives on pharmacological activities and mechanisms of the monoterpene borneol

BACKGROUND

Borneol, a highly lipid-soluble bicyclic terpene mainly extracted from plants, is representative of monoterpenoids. Modern medicine has established that borneol exhibits a range of pharmacological activities and used in the treatment of many diseases, particularly Cardio-cerebrovascular diseases (CVDs). The crucial role in enhancing drug delivery and improving bioavailability has attracted much attention. In addition, borneol is also widely utilized in food, daily chemicals, fragrances, and flavors industries.

PURPOSE

This review systematically summarized the sources, pharmacological activities and mechanisms, clinical trial, pharmacokinetics, toxicity, and application of borneol. In addition, this review describes the pharmacological effects of borneol ester and the combination of borneol with nanomaterial. This review will provide a valuable resource for those pursuing researches on borneol inspiring the pharmacological applications in the medicine, food and daily chemical products, and developing of new drugs containing borneol or its derivatives.

METHODS

This review searched the keywords ("borneol" or "bornyl esters") and ("pharmacology" or "Traditional Chinese medicine" or "Cardio-cerebrovascular diseases" or "blood-brain barrier" or "ischemic stroke" or "nanomaterials" or "neurodegenerative diseases" or "diabetes" or "toxicity") in Web of Science, PubMed, Google Scholar and China National Knowledge Infrastructure (CNKI) from January 1990 to May 2024. The search was limited to articles published in English and Chinese.

RESULTS

Borneol exhibits extensive pharmacological activities including anti-inflammatory effects, analgesia, antioxidation, and has the property of crossing biological barriers and treating CVDs. The intrinsic molecular mechanisms are involved in multiple components, such as regulation of various key factors (including Tumor necrosis factor-α, Nuclear factor kappa-B, Interleukin-1β, Malondialdehyde), inhibiting transporter protein function, regulating biochemical levels, and altering physical structural changes. In addition, this review describes the pharmacological effects of borneol ester and the combination of borneol with nanomaterial.

CONCLUSION

The pharmacological properties and applications of borneol are promising, including anti-inflammatory, analgesic, antimicrobial, and antioxidant properties, as well as enhancing drug delivery and treating CVDs. However, its clinical application is hindered by the limited research on safety, efficacy, and pharmacokinetics. Therefore, this review systemically summarized the advances on pharmacological activities and mechanisms of the borneol. Standardized clinical trials and exploration of synergistic effects with other drugs were also are outlined.

Phytol from Scoparia dulcis prevents NF-κB-mediated inflammatory responses during macrophage polarization

Macrophages are primary immune cells that mediate a wide range of inflammatory diseases through their polarization potential. In this study, phytol isolated from Scoparia dulcis has been explored against 7-ketocholesterol and bacterial lipopolysaccharide-induced macrophage polarization in IC-21 cells. Isolated phytol has been characterized using GC-MS, TLC, HPTLC, FTIR, 1H-NMR, and HPLC analyses. The immunomodulatory effects of viable concentrations of phytol were tested on oxidative stress, arginase activity, nuclear and mitochondrial membrane potentials in IC-21 cells in addition to the modulation of calcium and lipids. Further, gene and protein expression of atherogenic markers were studied. Results showed that the isolated phytol at a viable concentration of 400 µg/ml effectively reduced the production of nitric oxide, superoxide anion (ROS generation), calcium and lipid accumulation, stabilized nuclear and mitochondrial membranes, and increased arginase activity. The atherogenic markers including iNOS, COX-2, IL-6, IL-1β, MMP-9, CD36, and NF-κB were significantly downregulated at the levels of gene and protein expression, while macrophage surface and nuclear receptor markers (CD206, CD163, and PPAR-γ) were significantly upregulated by phytol pre-treatment in macrophages. Therefore, the present pharmacognostic study supports the role of phytol isolated from Scoparia dulcis in preventing M2-M1 macrophage polarization under inflammatory conditions, making it a promising compound.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-03924-9.

Chinese Herbal Medicines for Coronary Heart Disease: Clinical Evidence, Pharmacological Mechanisms, and the Interaction with Gut Microbiota

Coronary heart disease (CHD) is a common type of cardiovascular disease (CVD) that has been on the rise in terms of both incidence and mortality worldwide, presenting a significant threat to human health. An increasing body of studies has shown that traditional Chinese medicine (TCM), particularly Chinese herbal medicines (CHMs), can serve as an effective adjunctive therapy to enhance the efficacy of Western drugs in treating CHD due to their multiple targets and multiple pathways. In this article, we critically review data available on the potential therapeutic strategies of CHMs in the intervention of CHD from three perspectives: clinical evidence, pharmacological mechanisms, and the interaction with gut microbiota. We identified 20 CHMs used in clinical practice and it has been found that the total clinical effective rate of CHD patients improved on average by 17.78% with the intervention of these CHMs. Subsequently, six signaling pathways commonly used in treating CHD have been identified through an overview of potential pharmacological mechanisms of these 20 CHMs and the eight representative individual herbs selected from them. CHMs could also act on gut microbiota to intervene in CHD by modulating the composition of gut microbiota, reducing trimethylamine-N-oxide (TMAO) levels, increasing short-chain fatty acids (SCFAs), and maintaining appropriate bile acids (BAs). Thus, the therapeutic potential of CHMs for CHD is worthy of further study in view of the outcomes found in existing studies.

Natural Monoterpenes as Potential Therapeutic Agents against Atherosclerosis

Traditional herbal medicines based on natural products play a pivotal role in preventing and managing atherosclerotic diseases, which are among the leading causes of death globally. Monoterpenes are a large class of naturally occurring compounds commonly found in many aromatic and medicinal plants. Emerging evidence has shown that monoterpenes have many biological properties, including cardioprotective effects. Remarkably, an increasing number of studies have demonstrated the therapeutic potential of natural monoterpenes to protect against the pathogenesis of atherosclerosis. These findings shed light on developing novel effective antiatherogenic drugs from these compounds. Herein, we provide an overview of natural monoterpenes' effects on atherogenesis and the underlying mechanisms. Monoterpenes have pleiotropic and multitargeted pharmacological properties by interacting with various cell types and intracellular molecular pathways involved in atherogenesis. These properties confer remarkable advantages in managing atherosclerosis, which has been recognized as a multifaceted vascular disease. We also discuss limitations in the potential clinical application of monoterpenes as therapeutic agents against atherosclerosis. We propose perspectives to give new insights into future preclinical research and clinical practice regarding natural monoterpenes.

Glycosides from Buyang Huanwu Decoction inhibit atherosclerotic inflammation via JAK/STAT signaling pathway

BACKGROUND

Buyang Huanwu Decoction (BYHWD) has been used to treat or prevent cardiovascular disease. The prescription and its glycosides have the effects of protecting blood vessels, and resisting atherosclerosis. However, their protective mechanism of anti-atherosclerosis remains unclear.

PURPOSE

This study aims to explore whether glycosides are the main effective components of BYHWD in anti-atherosclerotic inflammation and whether their mechanism is related to the classical JAK/STAT inflammatory signaling pathway.

METHODS

UPLC-MSMS method was used to determine the main components of BYHWD and its glycosides. Network pharmacological analysis and molecular docking were used to predict the potential therapeutic targets of glycosides. Atherosclerosis model was prepared by feeding HFD in ApoE^-/- mice. The effects of glycosides on atherosclerosis were detected by blood lipids measurement, Masson staining, immunohistochemistry, immunofluorescence, western-blot and droplet digital PCR. RAW264.7 cells were used to establish foam cells model. The mechanism of glycosides anti-atherosclerotic inflammation was detected by measuring intracellular lipids, Oil Red O staining, ELISA, western-blot and droplet digital PCR.

RESULTS

1. Glycosides were absorbed into the blood through oral administrations and existed in the blood in the form of glycosides structures. 2. Glycosides attenuated hyperlipidemia, alleviated atherosclerotic lesions and inhibited inflammatory reaction. They could regulate blood lipids by decreasing TC, TG, LDL-c, increasing HDL-c level in ApoE^-/- mice, alleviating intimal area and thickness, and inhibiting atherosclerotic plaque formation, which were similar to BYHWD. 3. Glycosides anti-atherosclerotic inflammation was related to JAK/STAT signaling pathway by network pharmacology analysis. Interactions between glycosides (astragaloside IV, paeoniflorin and amygdalin) and JAK/STAT pathway-related proteins by molecular docking. 4. Glycosides alleviated atherosclerotic inflammation by decreasing the release of pro-inflammatory factors and adhesions molecules, inhibiting the activation of JAK/STAT pathway in vivo. 5. Glycosides reduced the number of foam cells and intracellular lipid content. It also prevented the inflammation of macrophages by decreasing the levels of pro-inflammatory factors, reducing the phosphorylation of JAK2, STAT1 and STAT3 in vitro.

CONCLUSION

This study demonstrated that glycosides were the main active components of BYHWD, and they could inhibit atherosclerosis by alleviating atherosclerotic inflammation. the mechanism is inhibiting the activation of JAK/STAT signaling pathway.

Comprehensive chemical profiling of volatile constituents of Angong Niuhuang Pill in vitro and in vivo based on gas chromatography coupled with mass spectrometry

Background

Angong Niuhuang Pill (ANP), a renowned precious traditional Chinese medicine prescription, is extensively utilized for the clinical treatment of stroke, meningitis and encephalorrhagia in China. As a classic resuscitation-inducing aromatic prescription, ANP has been investigated for its pharmacological effects in recent years, while the volatile composition in ANP still lacks comprehensive elucidation.

Method

To better explore the volatile constituents in ANP, a qualitative analysis method was developed based on gas chromatography coupled with mass spectrometry. Furthermore, a validated quantitative method was established to determine 21 main compounds in 8 batches of commercially available ANP samples by gas chromatography-tandem mass spectrometry. The quantitative data were successively subjected to Pearson correlation coefficient analysis. Additionally, the absorbed volatile constituents in rat plasma after single oral administration of ANP have also been characterized.

Results

A total of 93 volatile constituents including 29 sesquiterpenoids, 28 monoterpenoids, 13 fatty acids and their esters, 7 alkanes, 6 ketones, 3 phenols, 3 aldehydes, 2 benzoate esters, and 2 other types, were preliminarily characterized, which primarily originated from Borneolum, Moschus, Curcumae Radix, and Gardeniae Fructus. d-Borneol, isoborneol and muscone were the top three abundant ingredients (> 600 μg/g) in 8 batches of ANP samples. Subsequently, the average Pearson correlation coefficient of the contents of 21 analytes was 0.993, inferring the high batch-to-batch similarity among 8 batches. After oral administration of ANP, d-borneol, isoborneol, muscone and camphor were the main volatile constituents absorbed in the rat plasma.

Conclusion

This research may be helpful for the comprehensive quality control study of ANP, and provide for guarantee the clinical efficacy of ANP.

Inclisiran inhibits oxidized low-density lipoprotein-induced foam cell formation in Raw264.7 macrophages via activating the PPARγ pathway

Proprotein convertase subtilisin kexin type 9 (PCSK9) is a well-known proprotein convertase that influences foam cell formation and modulates atherosclerosis. Inclisiran is a novel chemosynthetic small interfering RNA that inhibits PCSK9 synthesis. This study aimed to explore the effect of inclisiran on oxidized low-density lipoprotein (ox-LDL)-induced foam cell formation in Raw264.7 macrophages and to investigate the underlying mechanisms. Raw264.7 cells were treated with ox-LDL to induce the formation of macrophage-derived foam cells. Oil Red O staining and high-performance liquid chromatography were performed to detect lipid accumulation and cholesterol levels. Dil-ox-LDL uptake assay, CCK-8, RT-qPCR, and Western blotting analysis were performed to examine ox-LDL uptake, cell viability, and expression of scavenger receptor-related factors. Inclisiran reduced lipid accumulation in ox-LDL-treated macrophages in a dose-dependent manner. Inclisiran significantly inhibited the levels of total cholesterol, free cholesterol, and cholesterol ester in the supernatant of Raw264.7 cells. Inclisiran reduced ox-LDL uptake and increased Raw264.7 cell viability. Meanwhile, inclisiran downregulated the expression of SR-A, LOX-1, and CD36 and upregulated SR-BI, ApoE, and ABCA1. Furthermore, inclisiran increased PPARγ activity and decreased NF-κB activity. An inhibitor of PPARγ (T0070907) reversed the beneficial effects of inclisiran on ox-LDL uptake, NF-κB inactivation, and cytokine expression. In conclusion, these data suggested that inclisiran inhibited the formation of macrophage-derived foam cells by activating the PPARγ pathway.HighlightsInclisiran reduces lipid accumulation in Raw264.7 cells;Inclisiran reduces ox-LDL uptake and increases Raw264.7 cell viability;Inclisiran inhibits foam cell formation by activating the PPARγ pathway.

Borneol in cardio-cerebrovascular diseases: Pharmacological actions, mechanisms, and therapeutics

With the coming acceleration of global population aging, the incidence rate of cardio-cerebrovascular diseases (CVDs) is increasing. It has become the leading cause of human mortality. As a natural drug, borneol (BO) not only has anti-inflammatory, anti-oxidant, anti-apoptotic, anti-coagulant activities and improves energy metabolism but can also promote drugs to enter the target organs or tissues through various physiological barriers, such as the blood-brain barrier (BBB), mucous membrane, skin. Thus, it has a significant therapeutic effect on various CVDs, which has been confirmed in a large number of studies. However, the pharmacological actions and mechanisms of BO on CVDs have not been fully investigated. Hence, this review summarizes the pharmacological actions and possible mechanisms of BO, which provides novel ideas for the treatment of CVDs.

Hydrogen sulfide improves ox‑LDL‑induced expression levels of Lp‑PLA2 in THP‑1 monocytes via the p38MAPK pathway

Hydrogen sulfide (H₂S) exerts an anti‑atherosclerotic effect and decreases foam cell formation. Lipoprotein‑associated phospholipase A2 (Lp‑PLA₂) is a key factor involved in foam cell formation. However, the association between H₂S and Lp‑PLA₂ expression levels with respect to foam cell formation has not yet been elucidated. The present study investigated whether H₂S can affect foam cell formation and potential signalling pathways via regulation of the expression and activity of Lp‑PLA₂. Using human monocytic THP‑1 cells as a model system, it was observed that oxidized low‑density lipoprotein (ox‑LDL) not only upregulates the expression level and activity of Lp‑PLA₂, it also downregulates the expression level and activity of Cystathionine γ lyase. Exogenous supplementation of H₂S decreased the expression and activity of Lp‑PLA₂ induced by ox‑LDL. Moreover, ox‑LDL induced the expression level and activity of Lp‑PLA₂ via activation of the p38MAPK signalling pathway. H₂S blocked the expression levels and activity of Lp‑PLA₂ induced by ox‑LDL via inhibition of the p38MAPK signalling pathway. Furthermore, H₂S inhibited Lp‑PLA₂ activity by blocking the p38MAPK signaling pathway and significantly decreased lipid accumulation in ox‑LDL‑induced macrophages, as detected by Oil Red O staining. The results of the present study indicated that H₂S inhibited ox‑LDL‑induced Lp‑PLA₂ expression levels and activity by blocking the p38MAPK signalling pathway, thereby improving foam cell formation. These findings may provide novel insights into the role of H₂S intervention in the progression of atherosclerosis.