Receptors Involved in COVID-19-Related Anosmia: An Update on the Pathophysiology and the Mechanistic Aspects.

Olfactory perception is an important physiological function for human well-being and health. Loss of olfaction, or anosmia, caused by viral infections such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has received considerable attention, especially in persistent cases that take a long time to recover. This review discusses the integration of different components of the olfactory epithelium to serve as a structural and functional unit and explores how they are affected during viral infections, leading to the development of olfactory dysfunction. The review mainly focused on the role of receptors mediating the disruption of olfactory signal transduction pathways such as angiotensin converting enzyme 2 (ACE2), transmembrane protease serine type 2 (TMPRSS2), neuropilin 1 (NRP1), basigin (CD147), olfactory, transient receptor potential vanilloid 1 (TRPV1), purinergic, and interferon gamma receptors. Furthermore, the compromised function of the epithelial sodium channel (ENaC) induced by SARS-CoV-2 infection and its contribution to olfactory dysfunction are also discussed. Collectively, this review provides fundamental information about the many types of receptors that may modulate olfaction and participate in olfactory dysfunction. It will help to understand the underlying pathophysiology of virus-induced anosmia, which may help in finding and designing effective therapies targeting molecules involved in viral invasion and olfaction. To the best of our knowledge, this is the only review that covered all the receptors potentially involved in, or mediating, the disruption of olfactory signal transduction pathways during COVID-19 infection. This wide and complex spectrum of receptors that mediates the pathophysiology of olfactory dysfunction reflects the many ways in which anosmia can be therapeutically managed.

Hypocholesterolemic effect of ß-caryophyllene in rats fed cholesterol and fat enriched diet.

Hypercholesterolemia is a major risk factor for cardiovascular diseases. This study investigated the cholesterol-lowering potential of ß-caryophyllene in a rat model. Hypercholesterolemia was induced by feeding male Wistar rats a high cholesterol and fat diet for 2 weeks. This was followed by oral administration of ß-caryophyllene to hypercholesterolemic rats at 30, 100 and 300 mg/kg b.w. for 4 weeks. A dose of 30 mg/kg of ß-caryophyllene significantly lowered serum total cholesterol, low density lipoprotein and the atherogenic index and significantly increased high density lipoprotein level. Moreover, it ameliorated liver injury as evidenced by decreasing hepatomegaly, macrovesicular steatosis and the activity of hepatic marker enzymes alanine aminotransferase and aspartate aminotransferase. Furthermore, it increased the activity of the antioxidant enzyme superoxide dismutase. This dose of ß-caryophyllene significantly inhibited the activity of hepatic hydroxy-methylglutaryl coenzyme A reductase. Higher doses (100 and 300 mg/kg) of ß-caryophyllene, however, did not induce significant beneficial effects on the studied parameters. These observations demonstrate that ß-caryophyllene has a cholesterol-lowering effect on hypercholesterolemic rats, thus offering protection against hypercholesterolemia-induced diseases such as atherosclerosis and fatty liver.

Liposome-Based Drug Delivery Systems in Cancer Research: An Analysis of Global Landscape Efforts and Achievements.

Lipid-bilayer-based liposomes are gaining attention in scientific research for their versatile role in drug delivery. With their amphiphilic design, liposomes efficiently encapsulate and deliver drugs to targeted sites, offering controlled release. These artificial structures hold great promise in advancing cancer therapy methodologies. Bibliometric research analyzes systematic literary data statistically. This study used bibliometric indicators to examine, map, and evaluate the applications of liposomes in cancer therapy. A Scopus search was conducted to identify all English-language peer-reviewed scientific publications on the applications of liposomes in cancer therapy within the past twenty years. Bibliometric indicators were calculated using VOSviewer and Biblioshiny. We produced thematic, conceptual, and visualization charts. A total of 14,873 published documents were obtained. The procedure of keyword mapping has effectively identified the main areas of research concentration and prevailing trends within this specific field of study. The significant clusters discovered through theme and hotspot analyses encompassed many topics such as the use of multiple strategies in chemotherapy and different forms of cancer, the study of pharmacokinetics and nanomedicine, as well as the investigation of targeted drug delivery, cytotoxicity, and gene delivery. Liposomes were employed as drug delivery systems so as to selectively target cancer cells and improve the bioavailability of anticancer drugs. The work showcased the capacity to tailor these liposomes for accurate drug delivery by including potent anticancer medications. Our findings not only bring attention to the latest progress in utilizing liposomes for cancer treatment but also underscore the vital need for ongoing research, collaborative efforts, and the effective translation of these breakthroughs into tangible clinical applications, emphasizing the dynamic and evolving nature of cancer therapeutics.

Potential of CDC25 phosphatases in cancer research and treatment: key to precision medicine.

The global burden of cancer continues to rise, underscoring the urgency of developing more effective and precisely targeted therapies. This comprehensive review explores the confluence of precision medicine and CDC25 phosphatases in the context of cancer research. Precision medicine, alternatively referred to as customized medicine, aims to customize medical interventions by taking into account the genetic, genomic, and epigenetic characteristics of individual patients. The identification of particular genetic and molecular drivers driving cancer helps both diagnostic accuracy and treatment selection. Precision medicine utilizes sophisticated technology such as genome sequencing and bioinformatics to elucidate genetic differences that underlie the proliferation of cancer cells, hence facilitating the development of customized therapeutic interventions. CDC25 phosphatases, which play a crucial role in governing the progression of the cell cycle, have garnered significant attention as potential targets for cancer treatment. The dysregulation of CDC25 is a characteristic feature observed in various types of malignancies, hence classifying them as proto-oncogenes. The proteins in question, which operate as phosphatases, play a role in the activation of Cyclin-dependent kinases (CDKs), so promoting the advancement of the cell cycle. CDC25 inhibitors demonstrate potential as therapeutic drugs for cancer treatment by specifically blocking the activity of CDKs and modulating the cell cycle in malignant cells. In brief, precision medicine presents a potentially fruitful option for augmenting cancer research, diagnosis, and treatment, with an emphasis on individualized care predicated upon patients' genetic and molecular profiles. The review highlights the significance of CDC25 phosphatases in the advancement of cancer and identifies them as promising candidates for therapeutic intervention. This statement underscores the significance of doing thorough molecular profiling in order to uncover the complex molecular characteristics of cancer cells.

Targeting Hypoxia-Inducible Factor-1 (HIF-1) in Cancer: Emerging Therapeutic Strategies and Pathway Regulation.

Hypoxia-inducible factor-1 (HIF-1) is a key regulator for balancing oxygen in the cells. It is a transcription factor that regulates the expression of target genes involved in oxygen homeostasis in response to hypoxia. Recently, research has demonstrated the multiple roles of HIF-1 in the pathophysiology of various diseases, including cancer. It is a crucial mediator of the hypoxic response and regulator of oxygen metabolism, thus contributing to tumor development and progression. Studies showed that the expression of the HIF-1α subunit is significantly upregulated in cancer cells and promotes tumor survival by multiple mechanisms. In addition, HIF-1 has potential contributing roles in cancer progression, including cell division, survival, proliferation, angiogenesis, and metastasis. Moreover, HIF-1 has a role in regulating cellular metabolic pathways, particularly the anaerobic metabolism of glucose. Given its significant and potential roles in cancer development and progression, it has been an intriguing therapeutic target for cancer research. Several compounds targeting HIF-1-associated processes are now being used to treat different types of cancer. This review outlines emerging therapeutic strategies that target HIF-1 as well as the relevance and regulation of the HIF-1 pathways in cancer. Moreover, it addresses the employment of nanotechnology in developing these promising strategies.

Vanillic Acid Inhibited the Induced Glycation Using In Vitro and In Vivo Models.

Background: Glycation is implicated in the pathophysiology of many diseases, including diabetes, cancer, neurodegenerative diseases, and aging. Several natural and synthetic compounds were investigated for their antiglycation activity. We evaluated the antiglycation effect of vanillic acid (VA) using in vitro and in vivo experimental models. Methods: In vitro, bovine serum albumin (BSA) (50 mg/ml) was incubated with glucose (50 mM) with or without VA at 1.0-100 mM for 1 week at 37°C, and then, excitation/emission fluorescence was measured at 370/440 nm to determine glycation inhibition. The cytoprotective effect of VA was evaluated using RAW 264.7 cells incubated with or without VA at 7.8-500 µM along with 100-400 µM of methylglyoxal for 48 hours, and cell viability was determined using the MTT assay. Aminoguanidine (AMG) was used as a positive control in both in vitro and cell culture experiments. In vivo, 52 streptozotocin-induced diabetic rats were randomly assigned to 4 groups and treated with 0, 1.5, 4.5, or 15 mg/kg VA for four weeks. Serum fructosamine and blood glycosylated hemoglobin (HbA1c) were then measured, and advanced glycation end-products (AGEs) were detected in the kidneys and the skin of deboned tails using an immunohistochemistry assay. Results: VA caused a concentration-dependent effect against BSA glycation (IC50 of 45.53 mM vs. 5.09 mM for AMG). VA enhanced cell viability at all concentrations of VA and methylglyoxal. VA did not affect serum fructosamine or blood HbA1c levels, although it markedly decreased AGEs in the kidney in a dose-dependent manner and decreased AGEs in the skin of deboned tail tissues. Conclusion: VA had significant antiglycation activity at cellular and long-term glycation.

The interaction of TRPV1 and lipids: Insights into lipid metabolism.

Transient receptor potential vanilloid 1 (TRPV1), a non-selective ligand-gated cation channel with high permeability for Ca2+, has received considerable attention as potential therapeutic target for the treatment of several disorders including pain, inflammation, and hyperlipidemia. In particular, TRPV1 regulates lipid metabolism by mechanisms that are not completely understood. Interestingly, TRPV1 and lipids regulate each other in a reciprocal and complex manner. This review surveyed the recent literature dealing with the role of TRPV1 in the hyperlipidemia-associated metabolic syndrome. Besides TRPV1 structure, molecular mechanisms underlying the regulatory effect of TRPV1 on lipid metabolism such as the involvement of uncoupling proteins (UCPs), ATP-binding cassette (ABC) transporters, peroxisome proliferation-activated receptors (PPAR), sterol responsive element binding protein (SREBP), and hypoxia have been discussed. Additionally, this review extends our understanding of the lipid-dependent modulation of TRPV1 activity through affecting both the gating and the expression of TRPV1. The regulatory role of different classes of lipids such as phosphatidylinositol (PI), cholesterol, estrogen, and oleoylethanolamide (OEA), on TRPV1 has also been addressed.

Ethanol Extract of Achillea fragrantissima Enhances Angiogenesis through Stimulation of VEGF Production.

OBJECTIVE: Achillea fragrantissima L. (Asteraceae) is a traditionally used medicinal herb in the rural communities of Jordan. METHODS: The present study evaluated the efficacy of the ethanol extract of this species on angiogenesis in both, ex vivo using a rat aortic ring assay and in vivo using a rat excision wound model. RESULTS: In concentrations of 50 and 100 µg/ml, the ethanol extract showed angiogenic stimulatory effect and significantly increased length of capillary protrusions around aorta rings of about 60% in comparison to those of untreated aorta rings. In MCF-7 cells, the ethanol extract of A. fragrantissima stimulated the production of VEGF in a dose-dependent manner. 1% and 5% of ethanol extract of A. fragrantissima containing vaseline based ointment was applied on rat excision wounds for six days and found to be effective in wound healing and maturation of the scar. Both preparations resulted in better wound healing when compared to the untreated control group and vaseline- treated group. This effect was comparable to that induced by MEBO, the positive control. CONCLUSION: The results indicate that A. fragrantissima has a pro-angiogenic effect, which may act through the VEGF signaling pathway.

Eugenol Reduces LDL Cholesterol and Hepatic Steatosis in Hypercholesterolemic Rats by Modulating TRPV1 Receptor.

Eugenol, a component of essential oils of medicinal and food plants, has a hypolipidemic effect in experimental animals although its mechanism of action is still unclear. This study aims to explore the mechanism of the hypolipidemic effect of eugenol in rats fed a high cholesterol and fat diet (HCFD). Eugenol significantly reduced total cholesterol (TC), low-density lipoproteins (LDL), atherogenic index (AI) but not high-density lipoproteins (HDL) or triglycerides (TG). Eugenol also decreased steatosis and hepatic inflammation in liver sections, decreased hepatomegaly, and the hepatic marker enzymes alanine aminotransferase (ALT) and alkaline phosphatase (ALP) activity and increased the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) activity in hypercholesterolemic rats. Eugenol did not inhibit hepatic 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase but caused down-regulation of transient receptor potential vanilloid (TRPV1) channels in the liver. Docking simulation using fast, rigid exhaustive docking (FRED) software indicated a tail-up/head-down interaction of eugenol with TRPV1 channel. Data indicate that eugenol does not inhibit HMG-CoA reductase but rather induces its action by interaction with TRPV1 channels.