Quinolone scaffolds as potential drug candidates against infectious microbes: a review.

Prevalence of microbial infections and new rising pathogens are signified as causative agent for variety of serious and lethal health crisis in past years. Despite medical advances, bacterial and fungal infections continue to be a rising problem in the health care system. As more bacteria develop resistance to antibiotics used in therapy, and as more invasive microbial species develop resistance to conventional antimicrobial drugs. Relevant published publications from the last two decades, up to 2024, were systematically retrieved from the MEDLINE/PubMed, SCOPUS, EMBASE, and WOS databases using keywords such as quinolones, anti-infective, antibacterial, antimicrobial resistance and patents on quinolone derivatives. With an approach of considerable interest towards novel heterocyclic derivatives as novel anti-infective agents, researchers have explored these as essential tools in vistas of drug design and development. Among heterocycles, quinolones have been regarded extremely essential for the development of novel derivatives, even able to tackle the associated resistance issues. The quinolone scaffold with its bicyclic structure and specific functional groups such as the carbonyl and acidic groups, is indeed considered a valuable functionalities for further lead generation and optimization in drug discovery. Besides, the substitution at N-1, C-3 and C-7 positions also subjected to be having a significant role in anti-infective potential. In this article, we intend to highlight recent quinolone derivatives based on the SAR approach and anti-infective potential such as antibacterial, antifungal, antimalarial, antitubercular, antitrypanosomal and antiviral activities. Moreover, some recent patents granted on quinolone-containing derivatives as anti-infective agents have also been highlighted in tabular form. Due consideration of this, future research in this scaffold is expected to be useful for aspiring scientists to get pharmacologically significant leads.

Understanding the Potential of mRNA as Biomarker to Revolutionize Diagnosis of Colorectal Cancer.

MicroRNA as potential biomarker for early diagnosis, differentiating various stages, interpreting the success of postoperative curative surgery and predicting early relapse of Colorectal cancer.In the realm of medical research, the quest to find effective biomarkers for various diseases has always been a top priority. Colorectal cancer (CRC), one of the leading causes of cancer-related deaths worldwide, is no exception. The emergence of microRNA (mRNA) as a potential biomarker for CRC has sparked immense interest among scientists and clinicians alike. mRNA, a molecule responsible for translating genetic information into functional proteins, presents a promising avenue for early detection and personalized treatment of this deadly disease. By analyzing the specific patterns and levels of mRNA expression in CRC cells, researchers have the ability to identify signatures that can aid in accurate diagnosis, predict patient prognosis, and even guide targeted therapies. This breakthrough in molecular biology not only enhances our understanding of CRC but also holds the potential to revolutionize the field of cancer diagnostics and treatment. In this article, we will delve deeper into the potential of mRNA as a biomarker for CRC, exploring its benefits and challenges in the field of cancer research.

Serum Gamma Glutamyl Transferase: Understanding its Contribution as a Potential Predictor of the Occurrence of Type 2 Diabetes.

INTRODUCTION: The liver and kidneys are the primary locations of the glutathione metabolism enzyme gamma-glutamyl transferase (GGT). The two main factors contributing to an increase are hepatic illnesses and excessive alcohol use. This study set out to test a theory on the predictive importance of the association between GGT and Type 2 diabetes mellitus. (T2DM). METHODS: In order to do this, we combed through PubMed, Google Scholar, Medline, and Science Direct for a wide range of information from previous studies. Attributes were established at the outset and compared to GGT concentration. RESULT: GGT, present in most cells, absorbs glutathione for intracellular antioxidant defences. This study links GGT to hepatic enzymes including HDL, LDL, and triglyceride. LDL, triglycerides, AST, and ALT increased with GGT concentration, but LDL decreased. Because of obesity, GGT production rises with BMI. We found that greater GGT levels were associated with more T2DM after analysing data from multiple sources. CONCLUSION: This literature review concludes that GGT is related to other factors such as BMI, HDL, AST, and triglycerides in the development of diabetes mellitus. Serum GGT was found to be a potential predictor of metabolic syndrome and T2DM.

Circulating MicroRNAs: Diagnostic Value as Biomarkers in the Detection of Non-alcoholic Fatty Liver Diseases and Hepatocellular Carcinoma.

Non-alcoholic fatty liver disease (NAFLD), a metabolic-related disorder, is the most common cause of chronic liver disease which, if left untreated, can progress from simple steatosis to advanced fibrosis and eventually cirrhosis or hepatocellular carcinoma, which is the leading cause of hepatic damage globally. Currently available diagnostic modalities for NAFLD and hepatocellular carcinoma are mostly invasive and of limited precision. A liver biopsy is the most widely used diagnostic tool for hepatic disease. But due to its invasive procedure, it is not practicable for mass screening. Thus, noninvasive biomarkers are needed to diagnose NAFLD and HCC, monitor disease progression, and determine treatment response. Various studies indicated that serum miRNAs could serve as noninvasive biomarkers for both NAFLD and HCC diagnosis because of their association with different histological features of the disease. Although microRNAs are promising and clinically useful biomarkers for hepatic diseases, larger standardization procedures and studies are still required.

SARS CoV-2 Omicron (B. 1.1. 529) Recent Updates and Challenges Worldwide.

The current world is plagued by unpredictability as a result of various COVID-19 variants. The current variants of concern (VOCs) are B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma) and B.1.617/B.1.617.2(Delta). WHO classified two variants, delta (B.1.617.2) and omicron (B.1.1.529), as having highly mutable strikes. The WHO predicted that it would be more dangerous than previous variants due to its mutatable capability. The Omicron variant of coronavirus has caused widespread disruption, with countries struggling to manage the massive number of infections. Due to its unique properties, such as protein structure, symptoms, transmission, and epidemiology, this review aims to compare omicron to other variants. Furthermore, we have highlighted vaccines that have been used to combat this pandemic.

Novel targets for potential therapeutic use in Diabetes mellitus.

Future targets are a promising prospect to overcome the limitation of conventional and current approaches by providing secure and effective treatment without compromising patient compliance. Diabetes mellitus is a fast-growing problem that has been raised worldwide, from 4% to 6.4% (around 285 million people) in past 30 years. This number may increase to 430 million people in the coming years if there is no better treatment or cure is available. Ageing, obesity and sedentary lifestyle are the key reasons for the worsening of this disease. It always had been a vital challenge, to explore new treatment which could safely and effectively manage diabetes mellitus without compromising patient compliance. Researchers are regularly trying to find out the permanent treatment of this chronic and life threatening disease. In this journey, there are various treatments available in market to manage diabetes mellitus such as insulin, GLP-1 agonist, biguanides, sulphonyl ureas, glinides, thiazolidinediones targeting the receptors which are discovered decade before. PPAR, GIP, FFA1, melatonin are the recent targets that already in the focus for developing new therapies in the treatment of diabetes. Inspite of numerous preclinical studies very few clinical data available due to which this process is in its initial phase. The review also focuses on the receptors like GPCR 119, GPER, Vaspin, Metrnl, Fetuin-A that have role in insulin regulation and have potential to become future targets in treatment for diabetes that may be effective and safer as compared to the conventional and current treatment approaches.

Design, Synthesis, Anti-microbial and Molecular Docking Studies of Novel 5-Pyrazyl-2-Sulfanyl-1, 3, 4-Oxadiazole Derivatives.

BACKGROUND: Chemical modification of Oxadiazole may lead to a potent therapeutic agent. A series of novel 5-pyrazyl-2-sulfanyl-1, 3, 4-oxadiazole derivatives (5ag) have been synthesised utilising pyrazinoic acid as a precursor. The new oxadiazole compounds were docked against potential targets and evaluated for antibacterial and antitubercular activity. METHODS: The 5-pyrazyl-2-substituted sulfanyl-1, 3,4-oxadiazole derivatives (5a-g) were synthesized from the crucial intermediate 2-sulfanyl-5-pyrazyl-1, 3,4-oxadiazole (4), which was prepared by treating the 2-pyrazyl hydrazide with CS2 and pyridine. IR, 1HNMR, 13C, MS and elemental analyses were used to confirm the chemical structures. RESULTS: Antimicrobial activity was determined for each synthesized compound. Additionally, compounds were evaluated for antitubercular activity against the Mycobacterium Tuberculosis H37Rv strain. Compounds 5c, 5g, and 5a had a favourable antibacterial profile, while 5c and 5g (MIC = 25 g/ml) demonstrated potential antitubercular activity when compared to the other produced compounds. Molecular docking experiments using V-Life Science MDS 4.6 supplemented the biological data. CONCLUSION: Each compound has been tested for antibacterial and antitubercular action against a variety of microorganism strains and exhibits considerable activity. Additionally, molecular docking analysis confirmed the experimental results by describing improved interaction patterns.

Medicinal Plants in Cancer Treatment: Contribution of Nuclear Factor- Kappa B (NF-kB) Inhibitors.

Nuclear factor-kappa B (NF-κB) is one of the principal inducible proteins and a predominant transcription factor that is known to control gene expression in mammals. It plays a pivotal role in regulating cell signalling in the body under certain physiological and pathological conditions. In cancer cells, such as colon, breast, pancreatic, ovarian, melanoma, and lymphoma, the NF-κB pathway is active. In cellular proliferation, promoting angiogenesis, invasion, metastasis of tumour cells, and blocking apoptosis, the constitutive activity of NF-κB signalling has been reported. Therefore, immense attention has been given to developing drugs targeting NF-κB signalling pathways to treat many types of tumours. They are a desirable therapeutic target for drugs, and many studies have concentrated on recognizing compounds. They may be able to reverse or standstill the growth and spread of tumours that selectively interfere with this pathway. Recently, numerous substances derived from plants have been evaluated as possible inhibitors of the NF-κB pathway. These include various compounds, such as flavonoids, lignans, diterpenes, sesquiterpenes, polyphenols, etc. A study supported by folk medicine demonstrated that plant-derived compounds could suppress NF-κB signalling. Considering this, the present review revealed the anticancer potential of naturally occurring compounds that inhibit the NF-κB signalling and suppress the growth and spread of cancer.

Styrylquinolines Derivatives: SAR Study and Synthetic Approaches.

In the present-day scenario, heterocyclic derivatives have revealed the primary function of various medicinal agents precious for humanity. Out of a diverse range of heterocycles, Styrylquinolines scaffolds have been proved to play an essential role in a broad range of biological activities, including anti-HIV-1, antimicrobial, anti-inflammatory, anti-Alzheimer activity with antiproliferative effects on tumor cell lines. Due to the immense pharmacological importance, distinct synthetic methods have been executed to attain new drug entities from Styrylquinolines. Various schemes for synthesizing Styrylquinolines derivatives like one-pot, ultrasound-promoted heterogeneous acid-catalysed, microwave-assisted, solvent-free, and green synthesis were discussed in the present review. Some products of Styrylquinolines are in clinical trials, and patents are also granted for the novel synthesis of Styrylquinolines. According to the structure-activity relationship, replacement at the R-7 and R-8 positions is required for various activities. In this review, recent synthetic approaches in the medicinal chemistry of Styrylquinolines and potent Styrylquinolines derivatives based on structural activity relationships (SAR) are outlined. Moreover, their primary methods and modifications are also discussed.

Appropriate Use of Antibiotics for the Management of Respiratory Tract Infections.

Lower Respiratory Tract Infections (LRTIs) and Upper Respiratory Tract Infections (URTIs) cause high morbidity and mortality worldwide. Lower respiratory tract infections are generally more serious than upper infections. Antibiotics are often inappropriately prescribed for patients with RTI. Inappropriate utilization of antibiotics, specifically the broad spectrum in respiratory tract infection, results in resistance to antibiotics. The common use of antibiotics is the prime reason for the spread of drug-resistant bacterial strains, which not only results in expensive treatments but also causes a high rate of morbidity and mortality due to undesired adverse effects of the drug. A literature survey was performed using PubMed, Science Direct, and Web of Science search engines. One hundred forty-five papers were retrieved, and more than 100 were included in this review. This article describes the overview and diagnosis of respiratory tract infections and the plethora of antibiotics that have been used in the management of RTIs.

Clinical Efficacy of Remdesivir and Favipiravir in the Treatment of COVID-19 Patients: Scenario so far.

The novel SARS-CoV-2 is a new disease that has caused severe destruction to human lives across the globe, including infection, mortality and financial crises, for which, scientific researchers have been directed towards the development of treatment and controlling measures against coronavirus. Currently, there has been no approved drug for the treatment of the disease, but several antiviral drugs have shown therapeutic effects from which, remdesivir and favipiravir are two such drugs. These drugs have shown some therapeutic potential in the treatment of COVID-19 by inhibiting viral enzyme RNA-dependent RNA polymerase. The purpose of this systematic review is to provide an overview of the effectiveness of these two drugs based on the clinical trials reported in current published data.

Exploring Quinolone Scaffold: Unravelling the Chemistry of Anticancer Drug Design.

Globally, cancer is considered as the major leading cause in burdening the patient's health care system globally. The growing threat of drug-resistant cancers renders an urgent need to develop more successful candidates for the anti-cancer therapy. In view of the outstanding pharmacological activities, Quinolone and its derivatives have attracted more attention towards drug designing and biological evaluation in the search for new drug molecules. The inspired researchers attempted efforts in order to discover the quinolone based analogs due to their wide range of biological activities. Due to immense pharmacological importance, distinct synthetic methods have been executed to attain new drug entities from quinolones and all the reported molecules have shown constructive anticancer activities. Some of the synthetic protocols like one pot synthesis, post-Ugi-transformation, catalysed based synthesis, enzyme-based synthesis and nano-catalyst based synthetic procedures are also discussed as recent advancements in the production of quinolone derivatives. In this review, recent synthetic approaches in the medicinal chemistry of quinolones and potent quinolone derivatives on the basis of structural activity relationship are outlined. Moreover, their major methods and modifications are discussed.

Exploring Azatidinone Moiety: An Insight into its Anti-tubercular Potency.

TB is becoming a worldwide problem and it was declared since 1993 by the World Health Organization (WHO), a global health emergency. The current problem of tuberculosis therapy is the emergence of multi-drug resistant (MDR) strains, caused by the improper use of antibiotics in chemotherapy of TB patients. Azatidinones, a ß-lactam cyclic amide with four atoms in a ring, has been considered as a magic moiety (wonder nucleus) which possesses almost all types of biological activities. This diversity in the biological response profile has attracted the attention of many researchers to explore this skeleton to its multiple potential against several activities. Present article is sincere attempt to review chemistry, method of synthesis of azatidinones and to study azatidinones synthesized in last few years which have shown potent antitubercular activity.

An Elite Scaffold and a Wonderful Pharmacophore in Drug Discovery: Styrylquinoline.

Styrylquinoline is a quinoline molecule linked to phenyl rings with an unsaturated ethylene linker, resulting in a flat and rigid conformation. The synthesis of the molecule was reported almost a century ago but was not much explored due to its adverse toxicity and poor selectivity. In the last two decades, a plethora of work was reported related to the synthesis and antiretroviral activity of several styrylquinoline derivatives. Later, other activities such as antimicrobial and anticancer abilities of these derivatives were also reported. In this review, we summarize the diverse steps of the development and analyze the spectrum of the activity of styrylquinolines and their utilization in drug design. Styrylquinolines are extensively explored for new pharmacological activities in recent years and this makes the moiety gain more visibility as a potential drug candidate and lead molecule in medicinal chemistry. The data obtained in vitro and ex vivo shed light on their different mechanism of action. Styrylquinoline has proved to be a potential lead molecule in medicinal chemist's toolkit due to the exploration of a variety of avenues of its activity as a drug candidate.

Evaluation and Docking Study of Pyrazine Containing 1, 3, 4-Oxadiazoles Clubbed with Substituted Azetidin-2-one: A New Class of Potential Antimicrobial and Antitubercular.

BACKGROUND: Tuberculosis (TB) caused by Mycobacterium tuberculosis is one of the main killers of people all over the world. The major hurdles with existing therapy are the lengthy regimen and appearance of multi drug resistant (MDR) and extensively drug resistant (XDR) strains of M.tuberculosis. AIMS: The present work was aimed to synthesize and determine antitubercular and antimicrobial potential of some novel 3-chloro-4-aryl-1-[4-(5-pyrazin-2-yl[1,3,4]oxadiazole-2-ylmethoxy)-phenyl]-azetidin-2-one derivatives 7: (A: -H: ) from pyrazinoic acid as precursor, which is a well-established antitubercular agent. Here we report the synthesis of a new class of heterocyclic molecules in which pyrazine, 1, 3, 4-oxadiazole and azetidinone moieties were present in one frame work. METHODS: Pyrazinoic acid (1: ) was esterified first (2: ) followed by amination to produce hydrazide (3: ) which was refluxed with POCl3 to obtain 2-chloromethyl-5pyrazino-1, 3, 4-oxadiazole (4: ). This was then further reacted with 4-amino phenol to obtain 4-[5-pyrazino-1, 3, 4-oxadiazol-2-yl-methoxy]-phenyl amine (5: ) which on condensation with various aromatic aldehydes afforded a series Schiff's bases 6(A-H): . Dehydrative annulations of 6(A-H): in the presence of chloroacetyl chloride and triethylamine yielded 3-chloro-4-aryl-1-[4-(5-pyrazin-2-yl-[1, 3, 4]oxadiazole-2-ylmethoxy)-phenyl]-azetidin-2-one derivatives 7(A-H): . Antibacterial, antifungal and antitubercular potential of all the synthesized compounds were assessed. Docking study was performed using the software VLife Engine tools of Vlifemds 4.6 on the protein lumazine synthase of M. tuberculosis (PDB entry code 2C92). RESULTS: The present studies demonstrated that synthesized oxadiazole derivatives have good antimicrobial activity against the various microorganisms. Among the synthesized derivative, 7B: and 7G: were found to be prominent compounds which have potential antibacterial, antifungal and antitubercular activity (with MIC 3.12 µg/ml and high dock score ranging from -59.0 to -54.0) against Mycobacterium tuberculosis. CONCLUSIONS: Derivatives 7B: and 7G: would be effective lead candidates for tuberculosis therapy.

Design, Synthesis and Enhanced BBB Penetration Studies of L-serine-Tethered Nipecotic Acid-Prodrug.

Nipecotic acid is considered to be one of the most potent inhibitors of neuronal and glial-aminobutyric acid (GABA) uptake in vitro. Due to its hydrophilic nature, nipecotic acid does not readily cross the blood-brain barrier (BBB). Large neutral amino acids (LAT1)-knotted nipecotic acid prodrug was designed and synthesized with the aim to enhance the BBB permeation by the use of carrier-mediated transport. The synthesized prodrug was tested in animal models of Pentylenetetrazole (PTZ)-induced convulsions in mice. Further pain studies were carried out followed by neurotoxicity estimation by writhing and rota-rod test respectively. HPLC data suggests that the synthesized prodrug has improved penetration through BBB. Nipecotic acid-L-serine ester prodrug with considerable anti-epileptic activity, and the ability to permeate the BBB has been successfully synthesized. Graphical Abstract.

Considering Circadian Pattern of Blood Pressure in the Treatment of Hypertension via Chronotherapy: A Conducive or Maladroit Approach.

Medical chronobiology deals with the way body's rhythm influences a person's health and disease states. To match body rhythms, deliberate alteration of drug concentration is done to optimize therapeutic outcomes and minimize size effects and this approach is known as Chronotherapeutics. In general the concept of homeostasis has been the base for the treatment of diseases. Little importance has been given in understanding biologic rhythms and their underlying mechanisms. Designing of cardiovascular drug is done to achieve a constant or near-constant effect throughout the 24-hour with the prescribed dose. However in many cases, medication requirement during night and day time are not the same. Body rhythms may have profound effect on the treatment outcomes. It is a wrongful approach to assume that a drug dosed in the morning or evening will have the same antihypertensive effect. The vast literature record of circadian variations in Blood Pressure (BP), heart rate, hormone secretion, and platelet aggregation are examples of the impact of chronobiology. In this study we analyze the effect of circadian pattern of blood pressure on action of various antihypertensives and investigate the perspective of chronotherapeutics- whether it is a fruitful approach and rationalize its utility in the treatment of hypertension.

Microbial Biofilm and Quorum Sensing Inhibition: Endowment of Medicinal Plants to Combat Multidrug-Resistant Bacteria.

Continued emergence and spread of multidrug-resistant bacteria behooved the development of alternative treatment strategies, including antimicrobial drugs. A hopeful approach is to target cellto- cell communications, commonly known as quorum-sensing (QS) and microbial biofilm formation. Quorum Sensing is a method used on bacteria to determine their physiological behavior and coordinate gene expression based on the cell to cell signaling. Many physiological functions of bacteria are controlled by quorum sensings such as virulence, motility, sporulation, luminescence, and biofilm formation. Microbial biofilms are organized aggregations of cells attached to a substratum and surrounded by a self-produced extrapolymeric substance (EPS) matrix. Currently, biofilm formation and quorum sensing are considered as a prospective novel target for antimicrobial therapy to control multidrug- resistant infections. Plant-based natural products have been comprehensively studied in this context. In this review, a comprehensive overview of various research papers published in the last decade on plant-derived molecules that are capable of inhibiting quorum sensing or microbial biofilm formation is reviewed, mentioning the biosynthetic classes of active compounds and their biological activity in the performed assays.

Synthetic Methods of Quinoline Derivatives as Potent Anticancer Agents.

BACKGROUND: On account of significant biological activities, quinoline derivatives have drawn more attention to the synthesis and biological activities in the search for new therapeutic agents. Several new synthetic approaches have been implemented to derive new molecules from quinoline and all the synthesized molecules showed effective anticancer activity. METHOD: Some molecules are synthesized using quinolones as precursor reactant, which is another effective product of quinoline, also showing significant activity against malignant tumors. The presence of nitrogen in it and its ability to bind with enzymes like gyrase, topoisomerase II and kinase have also proven it with antitumor activity. CONCLUSION: This review encapsulates the recent advances in the synthesis and anticancer activity of Quinoline derivatives.