Current Topics in Medicinal Chemistry - Volume 23, Issue 18, 2023

As an important pharmaceutical process, crystallization greatly impacts the final product. In recent years, the continuous crystallization process has attracted more attention from researchers, with the promotion of continuous manufacturing (CM) by the Food and Drug Administration (FDA). The continuous crystallization process has the advantages of high economic benefit, stable and uniform quality, a short production cycle, and personalization. To carry out continuous crystallization, some related process analytical technology (PAT) tools have become the focus of breakthroughs. Infrared (IR) spectroscopy, Raman spectroscopy, and focused beam reflection measurement (FBRM) tools have gradually become research hotspots due to their fast, non-destructive, and real-time monitoring characteristics. This review compared the advantages and disadvantages of the three technologies. Their applications in the upstream mixed continuous crystallization process, the middle reaches of crystal nucleation and growth, and the process of the downstream refining were discussed to provide corresponding guidance for the practice and further development of these three technologies in the continuous crystallization process and promote the development of CM in the pharmaceutical industry.

Epigenetics is defined as a heritable change occurring in gene expression and phenotype without altering the underlying primary DNA sequence itself. Epigenetic variation consists of DNA methylation repatterning, posttranslational modification of histone proteins, and non-coding RNAs (ncRNAs). Epigenetic modifications are deeply involved in tumorigenesis and tumor development. Epigenetic abnormalities can be therapeutically reversed, and three families of epigenetic marks, including “readers”, “writers” and “erasers”, could be modulated by epi drugs. Over the past decade, ten small-molecule epi drugs (e.g., inhibitors of DNA methyltransferases and histone deacetylases) have been approved by FDA or CFDA for the treatment of different cancers. Epigenetics therapy has been most effective in oncology and has become an attractive area in cancer treatment. Pulmonary hypertension (PH) encompasses a set of multifactorial diseases of progressive cardiopulmonary disorder. WHO classifies PH into five groups based on similar pathophysiological mechanisms, clinical presentation, haemodynamic characteristics, therapeutic management, and underlying etiology. Since PH shows many similarities with cancer, such as proliferation, resistance to apoptosis, and dysregulation of tumor suppressor genes, the current epigenetics therapeutic strategies used in cancer might be considered for the treatment of PH. The role of epigenetics in the setting of PH is a fast-growing field of research. In this review, we have summarized the up-to-date articles on the role of epigenetic mechanisms in the context of PH. The aim of this review is to provide a comprehensive insight from the epigenetics perspective and introduce the potential role of approved epi drugs in PH treatment.

The chronic infection of the hepatitis B virus (CHB) represents a major public health problem worldwide. Despite the availability of an effective prophylactic vaccine, millions of hepatitis B patients are at increased risk of developing chronic liver disease. The currently available treatments for HBV infection include interferon and nucleos(t)ide analogues that are effective at suppressing viral load and preventing or delaying the progression of liver disease. However, these treatments offer somewhat unsatisfactory clinical cures due to the persistence of the intrahepatic pool of covalently closed circular DNA (cccDNA) that serves as a reservoir for viral progenies and a potential source of recurring infections. Elimination of viral cccDNA remains a challenge for scientists and pharmaceutical industries in order to achieve the eradication and control of HBV infection. This would involve a detailed understanding of the molecular mechanisms of cccDNA formation, its intracellular stability, and regulation during replication and transcription. Recent advances in drug therapy have heralded a new horizon of novel therapeutic approaches for CHB infection, with several promising antiviral and immunomodulatory agents currently in preclinical or clinical testing. However, approval of any new curative therapy would involve rigorous evaluation of the efficacy and safety of each treatment and defining correct endpoints associated with improved clinical outcomes. This article summarizes the current landscape of HBV treatments, and drugs in clinical trials and highlights the most recent anti-HBV small molecules designed to directly target HBV or to improve immune response during chronic infection.

Propolis is a beehive product with great pharmacological potential, including antineoplastic activity. Objectives: The aim of this study is to provide an actual understanding of the existent scientific information regarding the antiproliferative effect of propolis, proposed mechanisms of action, and challenges to meet. Methods: An assessment of the scientific literature was attained using the PubMed and SciFinder platforms. Research papers, clinical trials, and reviews published between the years 2000 - 2021, were considered. The words “anticancer”, “antitumor”, “antiproliferative” and “propolis” were used in the search criteria. Conclusion: A summary of several antiproliferative activities of different types of propolis is exposed. The potential health benefits of propolis are discussed. The variable plant origin of propolis partially accounts for its anti-cancer activities. Even when some mechanisms of action of propolis have been proposed, much of the genesis of how this effect is produced is yet to be answered, including several molecular mechanisms in different biological systems.

Cancer is one of the leading causes of death worldwide. Each year, millions of people are diagnosed with cancer; hence, researchers have always been curious and busy developing cancer treatments. Despite thousands of studies, cancer is still a major threat to human beings. One of the mechanisms through which cancer invades a human being is the immune escape mechanism, which has been the focus of studies in the past years. PD-1/PD-L1 pathway plays a major role in this immune escape. Therefore, research focusing on blocking this pathway has led to the discovery of molecules based on monoclonal antibodies that work quite well, but despite the successful application of monoclonal antibodies as inhibitors of the PD-1/PD-L1 pathway, there are some drawbacks, such as poor bioavailability and several immune-related adverse effects, which have led the researchers toward further investigation, thereby resulting in the discovery of different types of molecules, such as small molecule inhibitors, PROTAC-based molecules, and naturally derived peptide molecules that function as inhibitors of the PD-1/PD-L1 pathway. Here, in this review, we have summarized recent findings of these molecules and focused on their structural activity relationship. The development of these molecules has opened more prospects in cancer therapy.

As a chronic encephalopathy, drug addiction is responsible for millions of deaths per year around the world. The gut microbiome is a crucial component of the human microbiome. Through dynamic bidirectional communication along the 'gut-brain axis,' gut bacteria cooperate with their hosts to regulate the development and function of the immune, metabolic, and nervous systems. These processes may affect human health because some brain diseases are related to the composition of gut bacteria, and disruptions in microbial communities have been implicated in neurological disorders. We review the compositional and functional diversity of the gut microbiome in drug addiction. We discuss intricate and crucial connections between the gut microbiota and the brain involving multiple biological systems and possible contributions by the gut microbiota to neurological disorders. Finally, the treatment of probiotics and fecal transplantation was summarized. This was done to further understand the role of intestinal microecology in the pathogenesis of drug addiction and to explore new methods for the treatment of drug addiction.