Activation of Piezo1 Inhibits Kidney Cystogenesis.

The disruption of calcium signaling associated with polycystin deficiency has been proposed as the primary event underlying the increased abnormally patterned epithelial cell growth characteristic of Polycystic Kidney Disease. Calcium can be regulated through mechanotransduction, and the mechanosensitive cation channel Piezo1 has been implicated in sensing of intrarenal pressure and in urinary osmoregulation. However, a possible role for PIEZO1 in kidney cystogenesis remains undefined. We hypothesized that cystogenesis in ADPKD reflects altered mechanotransduction, suggesting activation of mechanosensitive cation channels as a therapeutic strategy for ADPKD. Here, we show that Yoda-1 activation of PIEZO1 increases intracellular Ca 2+ and reduces forskolin-induced cAMP levels in mIMCD3 cells. Yoda-1 reduced forskolin-induced IMCD cyst surface area in vitro and in mouse metanephros ex vivo in a dose-dependent manner. Knockout of polycystin-2 dampened the efficacy of PIEZO1 activation in reducing both cAMP levels and cyst surface area in IMCD3 cells. However, collecting duct-specific Piezo1 knockout neither induced cystogenesis in wild-type mice nor affected cystogenesis in the Pkd1 RC/RC model of ADPKD. Our study suggests that polycystin-2 and PIEZO1 play a role in mechanotransduction during cystogenesis in vitro , and ex vivo , but that in vivo cyst expansion may require inactivation or repression of additional suppressors of cystogenesis and/or growth. Our study provides a preliminary proof of concept for PIEZO1 activation as a possible component of combination chemotherapy to retard or halt cystogenesis and/or cyst growth.

Growth Differentiation Factor 15 (GDF-15) Levels Associate with Lower Survival in Chronic Kidney Disease Patients with COVID-19.

A cytokine storm drives the pathogenesis of severe COVID-19 infection and several biomarkers have been linked to mortality. Chronic kidney disease (CKD) emerged as a risk factor for severe COVID-19. We investigated the association between selected biomarkers and mortality in 77 patients hospitalized for COVID-19, and whether they differ in patients with eGFR higher and lower than 45 mL/min. The association between patients' characteristics, plasma biomarkers and mortality was conducted by univariate logistic regression models and independent predictors of mortality were then used to create a multivariate prediction model through Cox regression. Patients with lower eGFR had a significant increase of GDF-15, CD-25 and RAGE, with higher plasma levels in non-survivors and in patients who needed ventilation. At univariate analysis, low and mid-low GDF-15 quartiles (<4.45 ng/mL) were associated with lower mortality risk, while mid-high and high quartiles (>4.45 ng/mL) were associated with higher mortality risk. Independent association between GDF-15 quartiles and mortality risk was confirmed in the Cox model and adjusted for eGFR, age, fever and dyspnea (HR 2.28, CI 1.53−3.39, p < 0.0001). The strength of the association between GDF-15 quartiles and mortality risk increased in patients with lower compared to higher eGFR (HR 2.53, CI 1.34−4.79 versus HR 1.99, CI 1.17−3.39). Our findings may suggest a further investigation of the effect of GDF-15 signaling pathway inhibition in CKD.

Association between SARS-CoV-2 RNAemia and dysregulated immune response in acutely ill hospitalized COVID-19 patients.

Severe/critical COVID-19 is associated with immune dysregulation and plasmatic SARS-CoV-2 detection (i.e. RNAemia). We detailed the association of SARS-CoV-2 RNAemia with immune responses in COVID-19 patients at the end of the first week of disease. We enrolled patients hospitalized in acute phase of ascertained SARS-CoV-2 pneumonia, and evaluated SARS-CoV-2 RNAemia, plasmatic cytokines, activated/pro-cytolytic T-cells phenotypes, SARS-CoV-2-specific cytokine-producing T-cells (IL-2, IFN-γ, TNF-α, IL-4, IL-17A), simultaneous Th1-cytokines production (polyfunctionality) and amount (iMFI). The humoral responses were assessed with anti-S1/S2 IgG, anti-RBD total-Ig, IgM, IgA, IgG1 and IgG3, neutralization and antibody-dependent cellular cytotoxicity (ADCC). Out of 54 patients, 27 had detectable viremia (viremic). Albeit comparable age and co-morbidities, viremic more frequently required ventilatory support, with a trend to higher death. Viremic displayed higher pro-inflammatory cytokines (IFN-α, IL-6), lower activated T-cells (HLA-DR+CD38+), lower functional SARS-CoV-2-specific T-cells (IFN-γ+CD4+, TNF-α+CD8+, IL-4+CD8+, IL-2+TNF-α+CD4+, and IL-2+TNF-α+CD4+ iMFI) and SARS-CoV-2-specific Abs (anti-S IgG, anti-RBD total-Ig, IgM, IgG1, IgG3; ID50, %ADCC). These data suggest a link between SARS-CoV-2 RNAemia at the end of the first stage of disease and immune dysregulation. Whether high ab initium viral burden and/or intrinsic host factors contribute to immune dysregulation in severe COVID-19 remains to be elucidated, to further inform strategies of targeted therapeutic interventions.

Cancer Extracellular Vesicles: Next-Generation Diagnostic and Drug Delivery Nanotools.

Nanosized extracellular vesicles (EVs) with dimensions ranging from 100 to 1000 nm are continuously secreted from different cells in their extracellular environment. They are able to encapsulate and transfer various biomolecules, such as nucleic acids, proteins, and lipids, that play an essential role in cell‒cell communication, reflecting a novel method of extracellular cross-talk. Since EVs are present in large amounts in most bodily fluids, challengeable hypotheses are analyzed to unlock their potential roles. Here, we review EVs by discussing their specific characteristics (structure, formation, composition, and isolation methods), focusing on their key role in cell biology. Furthermore, this review will summarize the biomedical applications of EVs, in particular those between 30 and 150 nm (like exosomes), as next-generation diagnostic tools in liquid biopsy for cancer and as novel drug delivery vehicles.

An Effective Multi-Stage Liposomal DNA Origami Nanosystem for In Vivo Cancer Therapy.

DNA origami systems could be important candidates for clinical applications. Unfortunately, their intrinsic properties such as the activation of non-specific immune system responses leading to inflammation, instability in physiological solutions, and a short in vivo lifetime are the major challenges for real world applications. A compact short tube DNA origami (STDO) of 30 nm in length and 10 nm in width was designed to fit inside the core of a stealth liposome (LSTDO) of about 150 nm to remote load doxorubicin. Biocompatibility was tested in three-dimensional (3D) organoid cultures and in vivo. Efficacy was evaluated in different cell lines and in a xenograft breast cancer mouse model. As described in a previous work, LSTDO is highly stable and biocompatible, escaping the recognition of the immune system. Here we show that LSTDO have an increased toleration in mouse liver organoids used as an ex vivo model that recapitulate the tissue of origin. This innovative drug delivery system (DDS) improves the antitumoral efficacy and biodistribution of doxorubicin in tumor-bearing mice and decreases bone marrow toxicity. Our application is an attractive system for the remote loading of other drugs able to interact with DNA for the preparation of liposomal formulations.

Proof-of-Concept Multistage Biomimetic Liposomal DNA Origami Nanosystem for the Remote Loading of Doxorubicin.

One of the most promising applications of DNA origami is its use as an excellent evolution of nanostructured intelligent systems for drug delivery, but short in vivo lifetime and immune-activation are still major challenges to overcome. On the contrary, stealth liposomes have long-circulation time and are well tolerated by the immune system. To overcome DNA origami limitations, we have designed and synthesized a compact short tube DNA origami (STDO) of approximately 30 nm in length and 10 nm in width. These STDO are highly stable ≥48 h in physiological conditions without any postsynthetic modifications. The compact size of STDO precisely fits inside a stealthy liposome of about 150 nm and could efficiently remotely load doxorubicin in liposomes (LSTDO) without a pH driven gradient. We demonstrated that this innovative drug delivery system (DDS) has an optimal tumoral release and high biocompatible profiles opening up new horizons to encapsulate many other hydrophobic drugs.

The Clinical Translation of Organic Nanomaterials for Cancer Therapy: A Focus on Polymeric Nanoparticles, Micelles, Liposomes and Exosomes.

BACKGROUND: The application of nanotechnology in the medical field is called nanomedicine. Nowadays, this new branch of science is a point of interest for many investigators due to the important advances in which we assisted in recent decades, in particular for cancer treatment. Cancer nanomedicine has been applied in different fields such as drug delivery, nanoformulation and nanoanalytical contrast reagents. Nanotechnology may overcome many limitations of conventional approaches by reducing the side effects, increasing tumor drug accumulation and improving the efficacy of drugs. In the last two decades, nanotechnology has rapidly developed, allowing for the incorporation of multiple therapeutics, sensing and targeting agents into nanoparticles (NPs) for developing new nanodevices capable to detect, prevent and treat complex diseases such as cancer. METHOD: In this review, we describe the main drug nanoformulations based on different types of organic NPs, the advantages that the new formulations present in comparison with their free drug counterparts and how nanodrugs have improved clinical care. We subdivided them into four main groups: polymeric NPs, liposomes, micelles and exosomes, a small subgroup that has only recently been used in clinical trials. RESULTS: The application of nanotechnology to pharmaceutical science has allowed us to build up nanosystems based on at least two stage vectors (drug/nanomaterial), which often shown better pharmacokinetics (PK), bioavailability and biodistribution. As a result of these advantages, the nanomaterials accumulate passively in the tumor (due to the enhanced permeability and retention, effect, EPR), thereby decreasing the side effects of free drug. Recently, many new drug formulations have been translated from bench to bedside. CONCLUSION: It is important to underline that the translation of nanomedicines from the basic research phase to clinical use in patients is not only expensive and time-consuming, but that it also requires appropriate funding. After many years spent in the design of innovative nanomaterials, it is now the time for the research to take into consideration the biological obstacles that nanodrugs have to overcome. Barriers such as the mononuclear phagocyte system, intratumoral pressure or multidrug resistance are regularly encountered when a cancer patient is treated, especially in the metastatic setting.

Inorganic Nanoparticles for Cancer Therapy: A Transition from Lab to Clinic.

BACKGROUND: Inorganic nanoparticles (NPs) including those derived from metals (e.g., gold, silver), semiconductors (e.g., quantum dots), carbon dots, carbon nanotubes, or oxides (e.g., iron oxide), have been deeply investigated recently for diagnostic and therapeutic purposes in oncology. Compared to organic nanomaterials, inorganic NPs have several advantages and unique characteristics for better imaging and drug delivery. Still, only a limited number of inorganic NPs are translated into clinical practice. METHOD: In this review, we discuss the progression of inorganic NPs for cancer therapy and imaging, focusing our attention on opportunities, limitations and challenges for the main constituting nanomaterials, including metallic and magnetic NPs. In particular, the pre-clinical and clinical trials from the bench toward the clinic are here investigated. RESULTS: Over the last few decades, the development of wide range of NPs with the ability to tune size, composition and functionality, has provided an excellent resource for nanomedicine. Inorganic NPs provide a great opportunity as drug carriers, due to the easy modification of targeting molecules, the control of drug release by different stimuli, and the effective delivery to target sites, thus resulting in having an improved therapeutic efficacy and in reducing side effects. Inorganic NPs are investigated in preclinical and clinical studies for the detection, diagnosis and treatment of many diseases. The stability of inorganic NPs offers a potential advantage over the traditional delivery methods. Inorganic NPs could enhance and improve current imaging and diagnostic techniques, such as MRI or PET. Even though, they have not yet been approved for drug delivery applications, their ability to respond to external stimuli is now widely investigated in clinic. CONCLUSION: The successful translation of inorganic NPs to the clinic requires the development of a simple, safe, cost-effective, ecofriendly mode of synthesis, and a better understanding of the safety mechanisms, biodistribution and the pharmacokinetics of NPs. However, more attention should be given to concerns on long-term toxicity, carcinogenesis, immunogenicity, inflammation and tissue damage. Although, some inorganic NPs, which were apparently promising in the preclinical phase, were found not to be successful when translated to the clinic, several encouraging NPs are currently being developed for treatment and cancer care and for a wide variety of other diseases.

Bottom-up synthesis of carbon nanoparticles with higher doxorubicin efficacy.

Nanomedicine requires intelligent and non-toxic nanomaterials for real clinical applications. Carbon materials possess interesting properties but with some limitations due to toxic effects. Interest in carbon nanoparticles (CNPs) is increasing because they are considered green materials with tunable optical properties, overcoming the problem of toxicity associated with quantum dots or nanocrystals, and can be utilized as smart drug delivery systems. Using black tea as a raw material, we synthesized CNPs with a narrow size distribution, tunable optical properties covering visible to deep red absorption, non-toxicity and easy synthesis for large-scale production. We utilized these CNPs to label subcellular structures such as exosomes. More importantly, these new CNPs can escape lysosomal sequestration and rapidly distribute themselves in the cytoplasm to release doxorubicin (doxo) with better efficacy than the free drug. The release of doxo from CNPs was optimal at low pH, similar to the tumour microenvironment. These CNPs were non-toxic in mice and reduced the tumour burden when loaded with doxo due to an improved pharmacokinetics profile. In summary, we created a new delivery system that is potentially useful for improving cancer treatments and opening a new window for tagging microvesicles utilized in liquid biopsies.

Exosomes increase the therapeutic index of doxorubicin in breast and ovarian cancer mouse models.

AIM: To demonstrate that exosomes (exo) could increase the therapeutic index of doxorubicin (DOX). MATERIALS & METHODS: Exosomes were characterized by nanoparticle tracking analysis and western blot. Tissue toxicity was evaluated by histopathological analysis and drug efficacy by measuring tumor volume. DOX biodistribution was analyzed by MS. RESULTS: Exosomal doxorubicin (exoDOX) avoids heart toxicity by partially limiting the crossing of DOX through the myocardial endothelial cells. For this reason, mice can be treated with higher concentration of exoDOX thus increasing the efficacy of DOX as demonstrated in breast and ovarian mouse tumors. CONCLUSION: ExoDOX is safer and more effective than free DOX. Importantly, the first spontaneous transformed syngeneic model of high-grade serous ovarian cancer was utilized for providing a new therapeutic opportunity.

Enhanced Chemotherapeutic Behavior of Open-Caged DNA@Doxorubicin Nanostructures for Cancer Cells.

In cancer therapy, it is imperative to increase the efficacy and reduce side effects of chemotherapeutic drugs. Nanotechnology offers the unique opportunity to overcome these barriers. In particular, in the last few years, DNA nanostructures have gained attention for their biocompatibility, easy customized synthesis and ability to deliver drugs to cancer cells. Here, an open-caged pyramidal DNA@Doxorubicin (Py-Doxo) nanostructure was constructed with 10 DNA sequences of 26-28 nucleotides for drug delivery to cancer cells. The synthesized DNA nanostructures are sufficiently stable in biological medium. Py-Doxo exhibited significantly enhanced cytotoxicity of the delivered doxorubicin to breast and liver cancer cells up to twofold compared to free doxorubicin. This study demonstrates the importance of the shape and structure of the designed transporter DNA nanostructures for biomedical applications.

Exosomal doxorubicin reduces the cardiac toxicity of doxorubicin.

AIM: To test the efficacy and toxicity of exosomal doxorubicin (exoDOX) compared with free doxorubicin. MATERIALS & METHODS: The cytotoxic effects of exoDOX were tested in vitro and in nude mice by measuring the tumor volume. The toxic effects were evaluated by measuring the bodyweight and through histopathologic analyses. The biodistribution of DOX was assessed by MS. RESULTS: In vitro and in vivo studies showed that exosomes did not decrease the efficacy of DOX. Surprisingly, exoDOX showed no cardiotoxicity as observed in DOX-treated mice and MS studies confirmed that the accumulation of exoDOX in the heart was reduced by approximately 40%. CONCLUSION: We demonstrated that exoDOX was less toxic than DOX through its altered biodistribution.

Biocompatible tailored zirconia mesoporous nanoparticles with high surface area for theranostic applications.

Nanocarriers as theranostic agents are under the spotlight in modern nanomedicine, and mesoporous nanomaterials represent a class of devices of major interest. Zirconia is biocompatible, inert with good mechanical and thermal properties for in vivo biomedical applications. Although a few examples of zirconia nanoparticles have been described, a major limitation was the low surface area, which is fundamental for payload transport. Here, a simple and highly efficient method is described for the synthesis of spherical mesoporous zirconia nanoparticles (MZNs) with a high surface area through a neutral surfactant-assisted sol-gel method. The combination of alkali halides and vacuum extraction allowed stabilization of the shape and size of MZNs and to avoid porous network failure, respectively. In comparison to published synthesis procedures, a high surface area has been obtained. Biological experiments demonstrated that MZNs were biocompatible, cell permeable and degradable providing a proof of concept for theranostic applications. A comparison with the properties of mesoporous silica nanoparticles has also been performed.