Exosomes in COVID-19 infection: Focus on role in diagnosis, pathogenesis, immunity, and clinical trials.

Since the end of 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread as a new strain of coronavirus disease (COVID-19) and progressed as a global pandemic. Exosomes are membrane-bound vesicles released from almost all cells and are crucially involved in cell-cell communication. Interestingly, COVID-19 viral particles produce exosomes that moderate communication between infected and uninfected cells. Hence, there is growing evidence highlighting the crucial implications of exosomes in COVID-19 infection, transmission, intercellular spread, and reinfection. On the other hand, clinical trials have demonstrated mesenchymal stem cell-derived exosomes as a promising therapeutic strategy for severely affected COVID-19 patients. Also, convalescent plasma-derived exosomes have been proposed for multiple efficacies in COVID-19 patients. Furthermore, messenger RNAs (mRNA)-loaded exosomes were superior to mRNA-loaded lipid nanoparticles as a delivery system. Hence, exosomes can be used to safely induce SARS-CoV-2 immunity via their loading with mRNAs encoding immunogenic forms of SARS-CoV-2 spike and nucleocapsid proteins. Moreover, exosomes can be used as a nano-delivery system for microRNA to alleviate cytokine storm and prevent the progression of organ failure in COVID-19 patients. The present review summarizes state of the art concerning the role of exosomes in COVID-19 infection and accompanying organ complications as well as the potential use of exosomes in COVID-19 diagnosis, treatment, drug delivery, and vaccination. The review also sheds the light on the common biogenic pathway between the SARS-CoV-2 virus and exosomes. Additionally, the latest and current clinical trials using exosomes for COVID-19 infection are summarized.

The Implication of Mechanistic Approaches and the Role of the Microbiome in Polycystic Ovary Syndrome (PCOS): A Review.

As a complex endocrine and metabolic condition, polycystic ovarian syndrome (PCOS) affects women's reproductive health. These common symptoms include hirsutism, hyperandrogenism, ovulatory dysfunction, irregular menstruation, and infertility. No one knows what causes it or how to stop it yet. Alterations in gut microbiota composition and disruptions in secondary bile acid production appear to play a causative role in developing PCOS. PCOS pathophysiology and phenotypes are tightly related to both enteric and vaginal bacteria. Patients with PCOS exhibit changed microbiome compositions and decreased microbial diversity. Intestinal microorganisms also alter PCOS patient phenotypes by upregulating or downregulating hormone release, gut-brain mediators, and metabolite synthesis. The human body's gut microbiota, also known as the "second genome," can interact with the environment to improve metabolic and immunological function. Inflammation is connected to PCOS and may be caused by dysbiosis in the gut microbiome. This review sheds light on the recently discovered connections between gut microbiota and insulin resistance (IR) and the potential mechanisms of PCOS. This study also describes metabolomic studies to obtain a clear view of PCOS and ways to tackle it.

Maxillary Mucormycosis Osteomyelitis in Post COVID-19 Patients: A Series of Fourteen Cases.

During the current pandemic of COVID-19, numerous manifestations and complications have developed. Patients with COVID-19 are at high risk of fungal infections, such as mucormycosis, that may result directly from COVID-19 infection and/or as a side effect of the drugs used in COVID-19 treatment protocol, such as dexamethasone, hydroxychloroquine, and antibiotics. In this report, we described a series of 14 cases with maxillary mucormycosis osteomyelitis in immediate post-COVID-19 patients.

Exosomes: Isolation, characterization, and biomedical applications.

Exosomes are nano-sized bioactive vesicles of 30-150 nm in diameter. They are secreted by exocytosis of nearly all type of cells in to the extracellular fluid. Thereby, they can be found in many biological fluids. Exosomes regulate intracellular communication between cells via delivery of their cargo which include lipids, proteins, and nucleic acid. Many desirable features of exosomes made them promising candidates in several therapeutic applications. In this review, we discuss the use of exosomes as diagnostic tools and their possible biomedical applications. Additionally, current techniques used for isolation, purification, and characterization of exosomes from both biological fluids and in vitro cell cultures were discussed.