Combinatorial Chemistry & High Throughput Screening - Volume 25, Issue 11, 2022

Infection by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) provokes acute inflammation due to extensive replication of the virus in the epithelial cells of the upper and lower respiratory system. The mammalian target of rapamycin (mTOR) is a l signalling protein with critical functions in cell growth, metabolism, and proliferation. It is known for its regulatory functions in protein synthesis and angiogenesis cascades. The structure of mTOR consists of two distinct complexes (mTORC1 and mTORC2) with diverse functions at different levels of the signalling pathway. By activating mRNA translation, the mTORC1 plays a key role in regulating protein synthesis and cellular growth. On the other hand, the functions of mTORC2 are mainly associated with cell proliferation and survival. By using an appropriate inhibitor at the right time, mTOR modulation could provide immunosuppressive opportunities as antirejection regimens in organ transplantation as well as in the treatment of autoimmune diseases and solid tumours. The mTOR also has an important role in the inflammatory process. Inhibitors of mTOR might indeed be promising agents in the treatment of viral infections. They have further been successfully used in patients with severe influenza A/H1N1 pneumonia and acute respiratory failure. The officially accepted mTOR inhibitors that have undergone clinical testing are sirolimus, everolimus, temsirolimus, and tacrolimus. Thus, further studies on mTOR inhibitors for SARS-CoV-2 infection or COVID-19 therapy are well merited.

Background: L-tryptophan is an essential amino acid necessary for the human body to function. Its degradation occurs through two metabolic pathways. Approximately 95 % of the Ltryptophan available in the body is converted via the kynurenine pathway, while the remainder is degraded via the serotonin pathway. Properly maintained balance between the concentrations of individual small molecular metabolites is extremely important to maintain homeostasis in the human body, and its disruption could lead to the development of numerous neurological, neurodegenerative, neoplastic, as well as cardiovascular diseases. Recent reports have suggested that by controlling the levels of selected L-tryptophan metabolites (potential biomarkers), it is possible to diagnose numerous diseases, monitor their course, and assess patient prognosis. Objective: The aim of this paper is to review the currently important clinical applications of selected biomarkers from the L-tryptophan metabolism pathways that would be helpful in early diagnosis, monitoring the course and treatment of serious diseases of affluence, which ultimately could improve the patients’ quality of life, as well as support targeted therapy of the aforementioned diseases. Conclusion: Since the biochemical biomarkers determination in body fluids presents the ideal minimally invasive tool in the patents’ diagnosis and prognostication, this study emphasizes the current trends and perspectives of application of analysis of selected L-tryptophan metabolites named kynurenine and serotonin-derived small compounds in the routine medical procedures.

The advancement of computing and technology has invaded all the dimensions of science. Artificial intelligence (AI) is one core branch of Computer Science, which has percolated to all the arenas of science and technology, from core engineering to medicines. Thus, AI has found its way for application in the field of medicinal chemistry and heath care. The conventional methods of drug design have been replaced by computer-aided designs of drugs in recent times. AI is being used extensively to improve the design techniques and required time of the drugs. Additionally, the target proteins can be conveniently identified using AI, which enhances the success rate of the designed drug. The AI technology is used in each step of the drug designing procedure, which decreases the health hazards related to preclinical trials and also reduces the cost substantially. The AI is an effective tool for data mining based on the huge pharmacological data and machine learning process. Hence, AI has been used in de novo drug design, activity scoring, virtual screening and in silico evaluation in the properties (absorption, distribution, metabolism, excretion and toxicity) of a drug molecule. Various pharmaceutical companies have teamed up with AI companies for faster progress in the field of drug development, along with the healthcare system. The review covers various aspects of AI (Machine learning, Deep learning, Artificial neural networks) in drug design. It also provides a brief overview of the recent progress by the pharmaceutical companies in drug discovery by associating with different AI companies.

The entire world has been in a battle against the COVID-19 pandemic since its first appearance in December 2019. Thus researchers are desperately working to find an effective and safe therapeutic agent for its treatment. The multifunctional coronavirus enzyme papain-like protease (PLpro) is a potential target for drug discovery to combat the ongoing pandemic responsible for cleavage of the polypeptide, deISGylation, and suppression of host immune response. The present review collates the in silico studies performed on various FDA-approved drugs, chemical compounds, and phytochemicals from various drug databases and represents the compounds possessing the potential to inhibit PLpro. Thus this review can provide quick access to a potential candidate to medicinal chemists to perform in vitro and in vivo experiments who are thriving to find the effective agents for the treatment of COVID-19.

Background: Malaria is responsible for social and economic burden in most lowincome malaria-affected countries. Thus, newer antimalarials are needed to tackle morbidities and mortalities associated with the drug-resistant malarial strains. Haemoglobin digestion inside the food vacuole of malarial parasite would lead to producing redox-active and toxic-free heme. The detoxification process adopted by Plasmodium sp. would give rise to hemozoin (Hz) (betahematin) formation. Targeting the pathway of hemozoin formation is considered a validated target for the discovery of newer antimalarials. Objective: This study aims to collect detailed information about aspects of hemozoin (Hz) (betahematin) inhibitors. Methods: A systemic search has been carried out using PubMed, Google Scholar, CNKI, etc., for relevant studies having the keyword, 'hemozoin or beta-hematin' for almost the last 2 decades (2000-2021). Results: This review tries to summarize all the recent advancements made for the developments of synthetic, natural isolated phytoconstituents and plant extracts inhibiting the hemozoin (betahematin) formation. Conclusion: Thus they would act as promising antimalarial candidates in the near future.

Background: Short-chain fatty acids exert anti-cancer effects on tumor cells. Objective: We aimed to reveal the signaling network altered by butyrate in Gastric Cancer (GC) using small RNA sequencing (sRNA-seq). Methods: The effects of butyrate on the biological behavior of NCI-N87 and KATO III cells in vitro were assessed by functional assays and half-maximal inhibitory concentrations (IC50) of butyrate in KATO III cells were calculated. sRNA-seq was performed on KATO III cells. Differentially expressed miRNAs (DE-miRNAs) were identified between butyrate treatment and control groups using DESeq2, and miRNA targets were predicted. A protein-protein interaction (PPI) network of DE-miRNA targets was created using Metascape. Key MCODE complexes were identified using the MCODE algorithm and cluster Profiler. The relationship between DE-miRNA and GC overall survival (OS) was evaluated using Kaplan-Meier curves. Results: Butyrate dose-dependently inhibited NCI-N87 and KATO III cell viability. KATO III cells were more sensitive to butyrate than NCI-N87 cells. Butyrate promoted apoptosis and inhibited KATO III cell migration. Total 324 DE-miRNAs were identified in KATO III cells, and 459 mRNAs were predicted as targets of 83 DE-miRNAs. Two key protein complexes were identified in a PPI network of the 459 targets. A key signaling network responding to butyrate was generated using targets in these key complexes and their miRNA regulators. The DE-miRNAs in the key signaling network were related to the OS of GC. Conclusion: Butyrate altered the biological behavior of GC cells, which may be achieved by regulating miRNAs and related oncogenic pathways.

Aims and Objectives: A high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determining hypaphorine, a potential agent for treating osteoclast- based bone loss, was developed and validated in rat plasma. Materials and Methods: Plasma samples were pretreated by the protein precipitation. Chromatographic separation was performed using an Inertsil ODS-3 column (50 mm × 4.6 mm, 5 μm). The mobile phase consisted of water (containing 0.1% formic acid) and acetonitrile in a gradient mode at a flow rate of 0.5 mL/min. The transitions from protonated precursor ion [M + H]⁺ to the particular daughter ion were acquired using selected reaction monitoring (SRM). The mass transitions of hypaphorine and IS were found to be 247 → 188 and m/z 219 → 188, respectively. The method was validated in terms of selectivity, linearity, accuracy and precision, extraction recovery and matrix effect, stability, and carryover. Results: It showed good linearity over the range of 1-2000 ng/mL (R² = 0.9978). The intra-batch accuracy was within 93.95-105.81%, and the precision was within 4.92-11.53%. The inter-batch accuracy was within 96.18-100.39% with a precision of 6.22-11.23%. The extraction recovery and matrix factors were acceptable. Conclusion: The simple and rapid method was successfully applied to the pharmacokinetic study in rats following oral administration of hypaphorine at the doses of 0.5, 1.5, and 4.5 mg/kg.

Background: Gastric cancer (GC), one of the common clinical malignant tumors of the digestive system, is the fourth most commonly diagnosed cancer and the second lethal cancer worldwide and has the characteristics of high metastasis, fatality, and recurrence rate. This research was conducted to investigate the role and mechanism of miR-4295 in gastric cancer. Methods: The expression capacity of miR-4295 was determined in gastric cancer tissues and its normal tissues by qRT-PCR. PTEN expression level was detected by western blot. SGC-7901 and MGC-803 cell lines were cultured and transfected with miR-4295 or its inhibitor. The effects of miR-4295 on cell proliferation, colony formation, migration, and invasion in vitro were investigated. The mutual effect between miR-4295 and PTEN in 293T cells was explored by luciferase reporter gene assays. Results: The results showed that miR-4295 expression was higher in gastric cancer tissues and cell lines, and the miR-4295 level was significantly negatively associated with the tumor size and distal metastasis of gastric cancer. Notably, up-regulated miR-4295 promoted cell proliferation, migration and invasion in vitro, whereas it led to contrary effects while down-regulating miR-4295 expression. Further mechanism studies displayed that miR-4295 could directly fasten the PTEN 3’UTR and dramatically decrease the level of PTEN in vitro. Conclusion: The findings revealed that miR-4295 could promote gastric cancer cell proliferation, migration and invasion, which might be attributed to targeting PTEN. Our study suggested that miR-4295 might be a potential therapeutic target for gastric cancer.

Aim & Objectives: The Gochnatia decora (Kurz) A. L. Cabrera is a rare woody plant belonging to the family of Asteraceae. The bark of this plant is used as a Chinese folk medicine to treat cough and pneumonia. However, the effective substance related to its efficacy remains unknown. This study aims to evaluate the potential anti-inflammatory activities of the chemicals isolated from this plant using a model of LPS-induced RAW264.7 cells. Materials and Methods: Chemical constituents were isolated from the stems and leaves of G. decora by a series of chromatographic separation methods and identified by spectral analysis techniques. The model of inflammation in vitro was established by treatment of 1μM LPS on RAW264.7 cells. The influence of tested compounds on inflammatory factor production, including NO, TNF-α, IL-1β, IL-6, IL-17, was determined by ELISA. The mechanisms involved were studied by western blot analysis. Results: Two known ent-kaurane diterpenes (1 and 2), identified as ent-17-hydroxy-15-oxokauran- 19-oic acid (1) and ent-15α-hydroxy-16-kauran-19-oic acid (2), were isolated from the stems and leaves of G. decora. The bioassay showed that both of them produced significant inhibition of LPS-induced release of NO, TNF-α, IL-1β, IL-6, IL-17, iNOS, and COX-2 expression. Western blot analysis showed that these two chemicals blocked LPS-induced phosphorylation of NF-ΚB. Conclusion: Compounds 1 and 2 were obtained from the genus Gochnatia.These compounds demonstrated useful anti-inflammatory activities in the model of LPS-induced RAW264.7 cells. A potential action mechanism may be the correlation of the NF-ΚB pathway.

Background: Osteoarthritis (OA) is a degenerative joint disease with an increasing incidence associated with increased life expectancy. The application of traditional Chinese medicine in the treatment of OA has become a research hotspot. Objective: This study investigated the effects of XGS externally applied to osteoarthritic joints and analyze its effect on pain in monosodium iodoacetate (MIA)-induced OA rats. This study also evaluates potential mechanisms behind the anti-osteoarthritic effects of XGS. Methods: A total of 24 Sprague Dawley rats were evenly and randomly divided into three separate groups, including the normal control (NC), OA and XGS groups. MIA (50 μL, 10 mg/mL) was injected into the left knee joints of the rats to induce OA. After 7 days, The rats of XGS group were given XGS (0.45 g) that was externally applied to the left knee joint, were fixed with gauze, and continuously administered XGS for 28 days. Morphological changes in tissues and organs were examined using H&E staining. Biochemical indicators were measured using an automatic biochemical analyzer. Inflammatory cytokines were detected using ELISA kits and immunohistochemistry. RNA-based high-throughput sequencing (RNA-seq) was performed to detect differential expression of mRNAs in normal and MIA–induced OA rats. Results: Stride of the left leg was extended in rats, matrix increased on cartilage tissue surfaces, and inflammatory cytokines were reduced when treated with XGS. RNA-seq results revealed that the PI3K-Akt signaling pathway is activated in the OA model. The qRT-PCR showed that the expression levels of Tnn, Col6a6, Igf1 and Lamb1 were up-regulated by XGS. Conclusion: Altogether, this work demonstrated the potential therapeutic effects of XGS in rats with OA induced by MIA. The XGS may be considered an alternative therapy to manage OA.

Background: The occurrence of oxidative stress is an important hallmark of tumorigenesis and the development of cancers, including head and neck squamous cell carcinoma (HNSCC). The purpose of this study was to identify a robust oxidative stress-related prognostic model in HNSCC. Methods: Oxidative stress genes related to the prognosis of HNSCC were identified through multiple bioinformatics methods. Results: The expression profile of differential genes related to oxidative stress and functional enrichment analysis were obtained from the HNSCC cohort of The Cancer Genome Atlas (TCGAHNSC). Then, the HNSCC prognostic risk model was constructed of thirteen screened genes through univariate Cox analysis, the least absolute shrinkage and selection operator (LASSO) Cox regression, and multivariate Cox analysis. Kaplan–Meier curve indicated that the low-risk group had a better survival outcome than the high-risk group. The clinical utility of the risk model was validated in the GSE41613 dataset. The risk score was an independent prognostic indicator in the training and validation sets. In addition, the risk score was in a positive correlation with tumor stage, lymph node infiltration, and the status of the primary site. Gene set enrichment analysis (GSEA) illustrated that many biological processes associated with immunity were significantly enriched in the low-risk group of the training cohort. Conclusion: The oxidative stress-related risk signature was a promising predictor for the prognosis of HNSCC patients, which might assist in making individualized therapy programs.

Background: Phencyclidine (PCP, I) and its substituted analogs are significant and broadly abused psychotomimetic drugs that affect the central nervous system. They possess many pharmacological properties due to the presence of specific receptors in the brain. Aims and Objective: Methyl group, despite strong electron-donating and characters of dipole moments, was placed on various positions of phenyl and amine moieties of phencyclidine along with the substitution of benzylamine, piperazine, and aniline derivatives in place of piperidine ring of phencyclidine to create novel compounds of the core with analgesic properties. Materials and Methods: For evaluation of the analgesic activities of newly synthesized compounds, they were screened by tests of tail immersion (thermal) and formalin (chemical) pains. The obtained data with the control and PCP groups were also compared. Results: The outcomes indicated that some new compounds have more antinociceptive effects than PCP in tail immersion and formalin tests. In the tail immersion test, the methyl piperazine analog (III) shows more efficacy than others. In the formalin test, none of the compounds are as effective as phencyclidine at the earliest time-point, but compounds IV and V show effectiveness during the second stage of formalin pain. Conclusion: It can be concluded that the methyl-piperazine analog of phencyclidine was the best candidate to decrease acute thermal pain, and benzylamine derivatives were suitable candidates to reduce chemical pains.

Aims and Objective: In this study, an attempt was made to synthesize, characterize, and develop many applications of functionalized rare metal oxide nanoparticles. Herein, a new strategy for drug delivery is developed to functionalize magnetite nanoparticles to improve their performances in the delivery of celecoxib. Materials and Methods: Magnetite Fe3O4@SiO2 nanoparticles are synthesized by the sol-gel method. The surface of the hydroxyl groups was extended by treating with cerium nitrate salt; finally, sodium hydroxide was anchored to the surface hydroxyl groups to produce cerium oxidefunctionalized Fe3O4@SiO2@CeO2 magnetic nanoparticles (FSC). The synthesized sample was characterized by FT-IR, FESEM, VSM, TGA, and XRD. Afterward, the functionalized nanoparticles were examined in the delivery of celecoxib as an active drug model involving cerium oxide and hydroxyl functional groups. Results: For this purpose, the amount of loading/release of the drug was investigated in different amounts of nanocomposite and pH values. Conclusion: The results of the present investigation indicate that the formulations (mFSC=5 mg, pH=3.3) can be considered as best among various formulations with respect to particle size, entrapment efficiency, and in-vitro successful drug release.