Research progress on antitumor activity of XRP44X and analogues as microtubule targeting agents.

Cancer threatens human health and life. Therefore, it is particularly important to develop safe and effective antitumor drugs. Microtubules, the main component of cytoskeleton, play an important role in maintaining cell morphology, mitosis, and signal transduction, which are one of important targets of antitumor drug research and development. Colchicine binding site inhibitors have dual effects of inhibiting proliferation and destroying blood vessels. In recent years, a series of inhibitors targeting this target have been studied and some progress has been made. XRP44X has a novel structure and overcomes some disadvantages of traditional inhibitors. It is also a multifunctional molecule that regulates not only the function of tubulin but also a variety of biological pathways. Therefore, the structure, synthesis, structure-activity relationship, and biological activity of XRP44X analogues reported in recent years were summarized in this paper, to provide a useful reference for the rational design of efficient colchicine binding site inhibitors.

The research progress on the anxiolytic effect of plant-derived flavonoids by regulating neurotransmitters.

Phytopharmaceuticals have attracted a lot of attention due to their multicomponent and multiple targets. The natural phenolic chemicals known as flavonoids are found in a wide variety of plants, fruits, vegetables, and herbs. Recently, they have been found to have modulatory effects on anxiety disorders, with current research focusing on the modulation of neurotransmitters. There has not yet been a review of the various natural flavonoid monomer compounds and total plant flavonoids that have been found to have anxiolytic effects. The study on the anti-anxiety effects of plant-derived flavonoids on neurotransmitters was reviewed in this paper. We, therefore, anticipate that further study on the conformational interaction underlying flavonoids' anti-anxiety effects will offer a theoretical framework for the creation of pertinent treatments.

Advances in antitumor research of CA-4 analogs carrying quinoline scaffold.

Combretastatin A-4 (CA-4) is a potent inhibitor of tubulin polymerization and a colchicine binding site inhibitor (CBSI). The structure-activity relationship study of CA-4 showed that the cis double bond configuration and the 3,4,5-trimethoxy group on the A ring were important factors to maintain the activity of CA-4. Therefore, starting from this condition, chemists modified the double bond and also substituted 3,4,5-trimethoxyphenyl with various heterocycles, resulting in a new generation of CA-4 analogs such as chalcone, Flavonoid derivatives, indole, imidazole, etc. Quinoline derivatives have strong biological activity and have been sought after by major researchers for their antitumor activity in recent years. This article reviews the research progress of novel CA-4 containing quinoline analogs in anti-tumor from 1992 to 2022 and expounds on the pharmacological mechanisms of these effective compounds, including but not limited to apoptosis, cell cycle, tubulin polymerization inhibition, immune Fluorescence experiments, etc., which lay the foundation for the subsequent development of CA-4 containing quinoline analogs for clinical use.

Inhibitory Effect of Isoliquiritigenin in Niemann-Pick C1-Like 1-Mediated Cholesterol Uptake.

Isoliquiritigenin (ISL) is a flavonoid with a chalcone structure extracted from the natural herb Glycyrrhiza glabra. Its anti-inflammatory, antibacterial, antioxidant, and anticancer activities have been extensively studied. Moreover, ISL also possess hypolipidemic and atherosclerosis-reducing effects. However, its cholesterol-lowering mechanisms have not been reported yet. Niemann Pick C1 Like 1 (NPC1L1) is a specific transporter of cholesterol uptake. In this study, we found for the first time that ISL downregulates NPC1L1 expression and competitively inhibits cellular cholesterol uptake by binding to NPC1L1 in a concentration-dependent manner in vitro. This study provides a theoretical basis for further investigation of the molecular mechanisms of its cholesterol-lowering effect in vivo and inspired emerging drug research for cholesterol-lowering purposes through NPC1L1 inhibition.

First Discovery of Cholesterol-Lowering Activity of Parthenolide as NPC1L1 Inhibitor.

Elevated cholesterol significantly increases the risk of developing atherosclerosis and coronary heart disease. The key to treating hypercholesterolemia is lowering plasma cholesterol levels. There have been no studies on the cholesterol-lowering potential of parthenolide (PTL), a naturally occurring small molecule from Tanacetum parthenium. Here, we first put forth PTL's cholesterol-lowering ability to inhibit cellular uptake of cholesterol in a dose-dependent manner. Its performance was on par with the positive control drug, ezetimibe. Niemann-Pick C1 Like-1 (NPC1L1) has been identified as a potential therapeutic target for hypercholesterolemia. The interaction of PTL with NPC1L1 could be explained by the results of molecular docking and filipin staining further reinforces this hypothesis. Furthermore, PTL reduced the expression of NPC1L1 in HepG2 cells in a concentration-dependent manner, which suggests that PTL functions as a potential NPC1L1 inhibitor with therapeutic potential for hypercholesterolemia.

Design, synthesis and biological evaluation of novel diarylpyridine derivatives as tubulin polymerisation inhibitors.

A set of novel diarylpyridines as anti-tubulin agents were designed, synthesised using a rigid pyridine as a linker to fix the cis-orientation of ring-A and ring-B. All of the target compounds were evaluated for their in vitro antiproliferative activities. Among them, 10t showed remarkable antiproliferative activities against three cancer cell lines (HeLa, MCF-7 and SGC-7901) in sub-micromolar concentrations. Consistent with its potent antiproliferative activity, 10t also displayed potent anti-tubulin activity. Cellular mechanism investigation elucidated 10t disrupted the cellular microtubule structure, arrested cell cycle at G2/M phase and induces apoptosis. Molecular modelling studies showed that 10t could bind to the colchicine binding site on microtubules. These results provide motivation and further guidance for the development of new CA-4 analogues.

Design, synthesis and biological evaluation of 9-aryl-5H-pyrido[4,3-b]indole derivatives as potential tubulin polymerization inhibitors.

A series of new 9-aryl-5H-pyrido[4,3-b]indole derivatives as tubulin polymerization inhibitors were designed, synthesized, and evaluated for antitumor activity. All newly prepared compounds were tested for their anti-proliferative activity in vitro against three different cancer cells (SGC-7901, HeLa, and MCF-7). Among the designed compounds, compound 7k displayed the strongest anti-proliferative activity against HeLa cells with IC50 values of 8.7 ± 1.3 µM. In addition, 7k could inhibit the polymerization of tubulin and disrupt the microtubule network of cells. Further mechanism studies revealed that 7k arrested cell cycle at the G2/M phase and induced apoptosis in a dose-dependent manner. Molecular docking analysis confirmed that 7k may bind to colchicine binding sites on microtubules. Our study aims to provide a new strategy for the development of antitumor drugs targeting tubulin.

Recent advances in the screening methods of NPC1L1 inhibitors.

NPC1L1 is a crucial protein involved in sterol lipid absorption and has been shown to play an important role in intestinal cholesterol absorption. Hypercholesterolemia is a significant risk factor for cardiovascular diseases such as coronary heart disease. Screening of NPC1L1 inhibitors is critical for gaining a full understanding of lipid metabolism, developing new cholesterol-lowering medicines, and treating cardiovascular diseases. This work summarized existing methodologies for screening NPC1L1 inhibitors and evaluated their challenges, and will assist the development of novel cholesterol-lowering medications and therapeutic strategies for hypercholesterolemia and other cholesterol-related metabolic disorders.

Emodin lows NPC1L1-mediated cholesterol absorption as an uncompetitive inhibitor.

Emodin (EM) is one of the active components of the traditional Chinese medicine rhubarb, and there is evidence of its hypolipidemic activity, though the exact mechanism is unknown. NPC1L1 is a key protein in human cholesterol uptake that is primarily expressed in hepatocytes and gastrointestinal epithelial cells. Our findings suggest that rhodopsin inhibits cellular cholesterol uptake by influencing NPC1L1 cholesterol transport. The results showed that NBD-cholesterol uptake in human HepG2 cells was 27 %, 31.3 %, 33.6 %, 41.6 %, and 52.6 % of control after treatment with 100, 75, 50, 25, and 12.5 % M EM, respectively, compared to 50 % for 100 M Ezetimibe. Kinetic studies revealed that EM inhibited cellular uptake of cholesterol through anti-competitive inhibition. Furthermore, using confocal fluorescence quantification, we discovered that after cholesterol deprivation treatment reintroduced cholesterol supply, cholesterol uptake was significantly higher in HepG2 cells highly expressing NPC1L1 than in U2OS cells with low NPC1L1 expression. As a result, we hypothesize that EM may inhibit cholesterol uptake via NPC1L1 in human hepatocytes in an anti-competitive manner. Overall, as a dietary supplement or lipid-modifying drug, EM has the potential to lower cholesterol.

Recent Advances on the Role of ATGL in Cancer.

The hypoxic state of the tumor microenvironment leads to reprogramming lipid metabolism in tumor cells. Adipose triglyceride lipase, also known as patatin-like phospholipase= domain-containing protein 2 and Adipose triglyceride lipase (ATGL), as an essential lipid metabolism-regulating enzyme in cells, is regulated accordingly under hypoxia induction. However, studies revealed that ATGL exhibits both tumor-promoting and tumor-suppressing effects, which depend on the cancer cell type and the site of tumorigenesis. For example, elevated ATGL expression in breast cancer is accompanied by enhanced fatty acid oxidation (FAO), enhancing cancer cells' metastatic ability. In prostate cancer, on the other hand, tumor activity tends to be negatively correlated with ATGL expression. This review outlined the regulation of ATGL-mediated lipid metabolism pathways in tumor cells, emphasizing the Hypoxia-inducible factors 1 (HIF-1)/Hypoxia-inducible lipid droplet-associated (HIG-2)/ATGL axis, peroxisome proliferator-activated receptor (PPAR)/G0/G1 switch gene 2 (G0S2)/ATGL axis, and fat-specific protein 27 (FSP-27)/Early growth response protein 1 (EGR-1)/ATGL axis. In the light of recent research on different cancer types, the role of ATGL on tumorigenesis, tumor proliferation, and tumor metastasis was systemically reviewed.

The role of NPC1L1 in cancer.

Lipid metabolism appears to play significant roles in the development of cancer. Numerous studies have shown that the evolution of malignancies, including breast, prostate, and colorectal cancers, involves cholesterol in a profound manner. A crucial part in the intestinal absorption of cholesterol is played by Niemann-Pick C1-like 1 (NPC1L1), a cholesterol transporter protein that is widely expressed in the small intestine and liver. The importance of NPC1L1 in tumor prognosis has been demonstrated in investigations in the interim. NPC1L1 also has the potential to develop into a new therapeutic target and a cancer marker. There is, however, no comprehensive review that summarizes NPC1L1's function in cancer. To this end, we outlined NPC1L1's functions in carcinogenesis and treatment, along with resources that can be used to further comprehend the connection between NPC1L1 and tumors.

Targeting NAD+: is it a common strategy to delay heart aging?

Heart aging is the main susceptible factor to coronary heart disease and significantly increases the risk of heart failure, especially when the aging heart is suffering from ischemia-reperfusion injury. Numerous studies with NAD+ supplementations have suggested its use in anti-aging treatment. However, systematic reviews regarding the overall role of NAD+ in cardiac aging are scarce. The relationship between NAD+ signaling and heart aging has yet to be clarified. This review comprehensively summarizes the current studies on the role of NAD+ signaling in delaying heart aging from the following aspects: the influence of NAD+ supplementations on the aging heart; the relationship and cross-talks between NAD+ signaling and other cardiac aging-related signaling pathways; Importantly, the therapeutic potential of targeting NAD+ in delaying heart aging will be discussed. In brief, NAD+ plays a vital role in delaying heart aging. However, the abnormalities such as altered glucose and lipid metabolism, oxidative stress, and calcium overload could also interfere with NAD+ function in the heart. Therefore, the specific physiopathology of the aging heart should be considered before applying NAD+ supplementations. We believe that this article will help augment our understanding of heart aging mechanisms. In the meantime, it provides invaluable insights into possible therapeutic strategies for preventing age-related heart diseases in clinical settings.

Niemann-Pick C1-Like 1 inhibitors for reducing cholesterol absorption.

Cholesterol is an important component of cell membrane. However, elevated level of serum cholesterol is a key risk factor for heart disease. Niemann-Pick C1-Like 1 (NPC1L1) is the crucial target involving in cholesterol cellar uptake. Ezetimibe is the first, and only, NPC1L1 inhibitor approved for the treatment of hypercholesterolemia through decreasing cholesterol absorption for nearly two decades. That means that the development of NPC1L1 inhibitors encounters much challenge, as well as offers exciting therapeutic opportunities. Substantial efforts have been undertaken to develop NPC1L1 inhibitors. The present review describes the mechanism of cholesterol transport by NPC1L1, highlights the development of NPC1L1 inhibitors, and discusses the current challenges.