Berberine attenuates diabetic atherosclerosis via enhancing the interplay between KLF16 and PPARα in ApoE−/− mice

ZFP36L1 controls KLF16 mRNA stability in vascular smooth muscle cells during restenosis after vascular injury

The RNA-binding zinc finger protein 36 (ZFP36) family participates in numerous physiological processes including transition and differentiation through post-transcriptional regulation. ZFP36L1 is a member of the ZFP36 family. This study aimed to evaluate the role of ZFP36L1 in restenosis. We found that the expression of ZFP36L1 was inhibited in VSMC-phenotypic transformation induced by TGF-β, PDGF-BB, and FBS and also in the rat carotid injury model. In addition, we found that the overexpression of ZFP36L1 inhibited the proliferation and migration of VSMCs and promoted the expression of VSMC contractile genes; whereas ZFP36L1 interference promoted the proliferation and migration of VSMCs and suppressed the expression of contractile genes. Furthermore, the RNA binding protein immunoprecipitation and double luciferase reporter gene experiments shows that ZFP36L1 regulates the phenotypic transformation of VSMCs through the posttranscriptional regulation of KLF16. Finally, our research results in the rat carotid balloon injury animal model further confirmed that ZFP36L1 regulates the phenotypic transformation of VSMCs through the posttranscriptional regulation of KLF16 and further plays a role in vascular injury and restenosis in vivo.

Natural products in atherosclerosis therapy by targeting PPARs: a review focusing on lipid metabolism and inflammation

Inflammation and dyslipidemia are critical inducing factors of atherosclerosis. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors and control the expression of multiple genes that are involved in lipid metabolism and inflammatory responses. However, synthesized PPAR agonists exhibit contrary therapeutic effects and various side effects in atherosclerosis therapy. Natural products are structural diversity and have a good safety. Recent studies find that natural herbs and compounds exhibit attractive therapeutic effects on atherosclerosis by alleviating hyperlipidemia and inflammation through modulation of PPARs. Importantly, the preparation of natural products generally causes significantly lower environmental pollution compared to that of synthesized chemical compounds. Therefore, it is interesting to discover novel PPAR modulator and develop alternative strategies for atherosclerosis therapy based on natural herbs and compounds. This article reviews recent findings, mainly from the year of 2020 to present, about the roles of natural herbs and compounds in regulation of PPARs and their therapeutic effects on atherosclerosis. This article provides alternative strategies and theoretical basis for atherosclerosis therapy using natural herbs and compounds by targeting PPARs, and offers valuable information for researchers that are interested in developing novel PPAR modulators.

PPARs in atherosclerosis: The spatial and temporal features from mechanism to druggable targets

BACKGROUND

Atherosclerosis is a chronic and complex disease caused by lipid disorder, inflammation, and other factors. It is closely related to cardiovascular diseases, the chief cause of death globally. Peroxisome proliferator-activated receptors (PPARs) are valuable anti-atherosclerosis targets that showcase multiple roles at different pathological stages of atherosclerosis and for cell types at different tissue sites.

AIM OF REVIEW

Considering the spatial and temporal characteristics of the pathological evolution of atherosclerosis, the roles and pharmacological and clinical studies of PPARs were summarized systematically and updated under different pathological stages and in different vascular cells of atherosclerosis. Moreover, selective PPAR modulators and PPAR-pan agonists can exert their synergistic effects meanwhile reducing the side effects, thereby providing novel insight into future drug development for precise spatial-temporal therapeutic strategy of anti-atherosclerosis targeting PPARs.

KEY SCIENTIFIC

Concepts of Review: Based on the spatial and temporal characteristics of atherosclerosis, we have proposed the importance of stage- and cell type-dependent precision therapy. Initially, PPARs improve endothelial cells' dysfunction by inhibiting inflammation and oxidative stress and then regulate macrophages' lipid metabolism and polarization to improve fatty streak. Finally, PPARs reduce fibrous cap formation by suppressing the proliferation and migration of vascular smooth muscle cells (VSMCs). Therefore, research on the cell type-specific mechanisms of PPARs can provide the foundation for space-time drug treatment. Moreover, pharmacological studies have demonstrated that several drugs or compounds can exert their effects by the activation of PPARs. Selective PPAR modulators (that specifically activate gene subsets of PPARs) can exert tissue and cell-specific effects. Furthermore, the dual- or pan-PPAR agonist could perform a better role in balancing efficacy and side effects. Therefore, research on cells/tissue-specific activation of PPARs and PPAR-pan agonists can provide the basis for precision therapy and drug development of PPARs.

A network pharmacology method explores the molecular mechanism of Coptis chinensis for the treatment of Alzheimer's disease

To predict the molecular mechanisms of action of Coptis chinensis in the treatment of Alzheimer's disease using network pharmacology. The active ingredients and targets of Coptis chinensis were obtained from the Traditional Chinese Medicine System Pharmacology Database. Target information for Alzheimer's disease was screened using the GeneCard and OMIM databases. The Venn diagram tool was used to identify the intersecting targets of Coptis chinensis and Alzheimer's disease. The obtained target information was entered into the STRING database to construct a protein-protein interaction network. The R language was used to perform Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses of significant targets. Auto Dock Vina software was used for molecular docking. Fourteen effective active ingredients and 158 key targets associated with Coptis chinensis were identified. There were 1113 targets related to Alzheimer's disease genes. A drug-component-disease-target network was constructed and 84 key targets were identified for the treatment of Alzheimer's disease by Coptis chinensis. The main signaling pathways were the PI3K-Akt, AGE-RAGE, MAPK, HIF-1, TNF, and relaxin signaling pathways. The molecular docking results showed that berberine has a high affinity for Alzheimer's Disease. Coptis chinensis could play a multi-target and multi-pathway role against Alzheimer's disease, which has guiding significance for clinical research.

Inhibiting anti-angiogenic VEGF165b activates a miR-17-20a-Calcipressin-3 pathway that revascularizes ischemic muscle in peripheral artery disease

BACKGROUND

VEGF165a increases the expression of the microRNA-17-92 cluster, promoting developmental, retinal, and tumor angiogenesis. We have previously shown that VEGF165b, an alternatively spliced anti-angiogenic VEGF-A isoform, inhibits the VEGFR-STAT3 pathway in ischemic endothelial cells (ECs) to decrease their angiogenic capacity. In ischemic macrophages (Møs), VEGF165b inhibits VEGFR1 to induce S100A8/A9 expression, which drives M1-like polarization. Our current study aims to determine whether VEGF165b inhibition promotes perfusion recovery by regulating the microRNA(miR)-17-92 cluster in preclinical PAD.

METHODS

Femoral artery ligation and resection was used as a preclinical PAD model. Hypoxia serum starvation (HSS) was used as an in vitro PAD model. VEGF165b was inhibited/neutralized by an isoform-specific VEGF165b antibody.

RESULTS

Here, we show that VEGF165b-inhibition induces the expression of miR-17-20a (within miR-17-92 (miR-17-18a-19a-19b-20a-92) cluster) in HSS-ECs and HSS-Møs vs. respective normal and/or isotype-matched IgG controls to enhance perfusion recovery. Consistent with the bioinformatics analysis that revealed RCAN3 as a common target of miR-17 and miR-20a, Argonaute-2 pull-down assays showed decreased miR-17-20a expression and higher RCAN3 expression in the RNA-induced silencing complex of HSS-ECs and HSS-Møs vs. respective controls. Inhibiting miR-17-20a induced RCAN3 levels to decrease ischemic angiogenesis and promoted M1-like polarization to impair perfusion recovery. Finally, using STAT3 inhibitors, S100A8/A9 silencers, and VEGFR1-deficient ECs and Møs, we show that VEGF165b-inhibition activates the miR-17-20a-RCAN3 pathway independent of VEGFR1-STAT3 or VEGFR1-S100A8/A9 in ischemic-ECs and ischemic-Møs respectively.

CONCLUSIONS

Our data revealed a hereunto unrecognized therapeutic 'miR-17-20a-RCAN3' pathway in the ischemic vasculature that is VEGFR1-STAT3/S100A8/A9 independent and is activated only upon VEGF165b-inhibition in PAD.

Bitter yet beneficial: The dual role of dietary alkaloids in managing diabetes and enhancing cognitive function

With the rising prevalence of diabetes and its association with cognitive impairment, interest in the use of dietary alkaloids and other natural products has grown significantly. Understanding how these compounds manage diabetic cognitive dysfunction (DCD) is crucial. This comprehensive review explores the etiology of DCD and the effects of alkaloids in foods and dietary supplements that have been investigated as DCD therapies. Data on how dietary alkaloids like berberine, trigonelline, caffeine, capsaicin, 1-deoxynojirimycin, nuciferine, neferine, aegeline, tetramethylpyrazine, piperine, and others regulate cognition in diabetic disorders were collected from PubMed, Research Gate, Web of Science, Science Direct, and other relevant databases. Dietary alkaloids could improve memory in behavioral models and modulate the mechanisms underlying the cognitive benefits of these compounds, including their effects on glucose metabolism, gut microbiota, vasculopathy, neuroinflammation, and oxidative stress. Evidence suggests that dietary alkaloids hold promise for improving cognition in diabetic patients and could open exciting avenues for future research in diabetes management.

Eco-friendly chitosan-based nanostructures in diabetes mellitus therapy: Promising bioplatforms with versatile therapeutic perspectives

Nature-derived polymers, or biopolymers, are among the most employed materials for the development of nanocarriers. Chitosan (CS) is derived from the acetylation of chitin, and this biopolymer displays features such as biocompatibility, biodegradability, low toxicity, and ease of modification. CS-based nano-scale delivery systems have been demonstrated to be promising carriers for drug and gene delivery, and they can provide site-specific delivery of cargo. Owing to the high biocompatibility of CS-based nanocarriers, they can be used in the future in clinical trials. On the other hand, diabetes mellitus (DM) is a chronic disease that can develop due to a lack of insulin secretion or insulin sensitivity. Recently, CS-based nanocarriers have been extensively applied for DM therapy. Oral delivery of insulin is the most common use of CS nanoparticles in DM therapy, and they improve the pharmacological bioavailability of insulin. Moreover, CS-based nanostructures with mucoadhesive features can improve oral bioavailability of insulin. CS-based hydrogels have been developed for the sustained release of drugs and the treatment of DM complications such as wound healing. Furthermore, CS-based nanoparticles can mediate delivery of phytochemicals and other therapeutic agents in DM therapy, and they are promising compounds for the treatment of DM complications, including nephropathy, neuropathy, and cardiovascular diseases, among others. The surface modification of nanostructures with CS can improve their properties in terms of drug delivery and release, biocompatibility, and others, causing high attention to these nanocarriers in DM therapy.

L-limonene reduces aortic artery atherosclerosis by inhibiting oxidative stress/inflammatory responses in diabetic rats fed high-fat diet

Atherosclerosis, a leading cause of mortality worldwide, is driven by multiple risk factors such as diabetes. Oxidative stress and inflammation assist interrelated roles in diabetes-accelerated atherosclerosis. Thereby, treatment of diabetic atherosclerosis from an oxidative stress/inflammatory perspective seems to be a more effective modality to prevent and delay plaque formation and progression. This study aimed to evaluate the effects of l-limonene (LMN) on oxidative stress/inflammatory responses in the aortic artery of diabetic atherosclerosis-modeled rats. Male Wistar rats (n = 30, 250-280 g, 12 weeks old) were used to establish a diabetic atherosclerosis model (8 weeks) using high-fat diet/low-dose streptozotocin. LMN (200 mg/kg/day) was administered orally, starting on day 30^th before tissue sampling. Plasma lipid profiles, aortic histopathological changes, atherogenic index, aortic artery levels of oxidative stress markers (manganese superoxide dismutase, glutathione, and 8-isoprostane), inflammatory markers (tumor necrosis factor-alpha, interleukin (IL)-6, and IL-10), and expression of phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK)/AMPK, Sirtuin 1 (SIRT1), and p-p65/p65 proteins were evaluated. The administration of LMN to diabetic rats improved lipid profiles, aortic histopathological morphology, and atherogenic index (P < 0.05 to P < 0.001). It also increased enzymatic antioxidant activities, decreased 8-isoprostane level, suppressed inflammatory response, upregulated p-AMPK and SIRT1 proteins, and downregulated p-p65 protein (P < 0.05 to P < 0.01). Inhibiting the AMPK through the administration of compound C significantly abolished or reversed the positive effects of LMN in diabetic rats (P < 0.05 to P < 0.01). LMN treatment had dual anti-oxidative and anti-inflammatory actions against atherosclerosis in the aortic artery of diabetic rats. Atheroprotection by LMN was mediated partly through modulation of AMPK/SIRT1/p65 nuclear factor kappa B signaling pathway. LMN appears to be a promising anti-atherosclerotic modality to improve the quality of life in diabetic patients.

PPARα: An emerging target of metabolic syndrome, neurodegenerative and cardiovascular diseases

Peroxisome proliferator-activated receptor α (PPARα) is a ligand-activated transcription factor that is involved in lipid metabolism of various tissues. Different metabolites of fatty acids and agonists like fibrates activate PPARα for its transactivative or repressive function. PPARα is known to affect diverse human diseases, and we focus on advanced studies of its transcriptional regulation in these diseases. In MAFLD, PPARα shows a protective function with its upregulation of lipid oxidation and mitochondrial biogenesis and transcriptional repression of inflammatory genes, which is similar in Alzheimer's disease and cardiovascular disease. Activation of PPARα also prevents the progress of diabetes complications; however, its role in diabetes and cancers remains uncertain. Some PPARα-specific agonists, such as Wy14643 and fenofibrate, have been applied in metabolic syndrome treatment, which might own potential in wider application. Future studies may further explore the functions and interventions of PPARα in cancer, diabetes, immunological diseases, and neurodegenerative disease.