COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has overwhelmed Healthcare Systems requiring the rapid development of treatments, at least, to reduce COVID-19 severity. Drug repurposing offers a fast track. Here, we discuss the potential beneficial effects of statins in COVID-19 patients based on evidence that they may target virus receptors, replication, degradation and downstream responses in infected cells, addressing both basic research and epidemiological information. Briefly, statins could act modulating virus entry, acting on the SARS-CoV-2 receptors, ACE2 and CD147, and/or lipid rafts engagement. Statins, by inducing autophagy activation, could regulate virus replication or degradation, exerting protective effects. The well-known anti-inflammatory properties of statins, by blocking several molecular mechanisms, including NF-κB and NLRP3 inflammasome, could limit the “cytokine storm” in severe COVID-19 patients which is linked to fatal outcome. Finally, statin moderation of coagulation response activation may also contribute to improve COVID-19 outcomes.

Peptides play a key role in controlling many physiological and neurobiological pathways. Many bioactive peptides require a C-terminal α-amide for full activity. The bifunctional enzyme catalyzing α-amidation, peptidylglycine α-amidating monooxygenase (PAM), is the sole enzyme responsible for amidated peptide biosynthesis, from Chlamydomonas reinhardtii to Homo sapiens. Many neuronal and endocrine functions are dependent upon amidated peptides; additional amidated peptides are growth promoters in tumors. The amidation reaction occurs in two steps, glycine α-hydroxylation followed by dealkylation to generate the α-amide product. Currently, most potentially useful inhibitors target the first reaction, which is rate-limiting. PAM is a membrane-bound enzyme that visits the cell surface during peptide secretion. PAM is then used again in the biosynthetic pathway, meaning that cell-impermeable inhibitors or inactivators could have therapeutic value for the treatment of cancer or psychiatric abnormalities. To date, inhibitor design has not fully exploited the structures and mechanistic details of PAM.

Background and Purpose: The development of effective therapeutic strategies against Alzheimer’s disease (AD) remains a challenge. I2 Imidazoline receptors (I2-IR) ligands have a neuroprotective role in AD. While co-treatment of acetylcholinesterase inhibitors with neuroprotective agents have shown better effects on the prevention of dementia. Here, we assessed the potential therapeutic effect of the I2-IR ligand LSL60101, donepezil and their combination in 5XFAD mice. Experimental Approach: 5XFAD female mice were treated with low doses of LSL60101 (1mg/kg/day), donepezil (1mg/kg/day), and donepezil plus LSL60101 (1+1mg/kg/day), during 4 weeks per os. Novel object recognition, Morris water maze, open field, elevated plus maze and three-chamber tests were employed to evaluate the cognitive and behavioural status of the mice after treatment. The effects of the treatments on AD-like pathology were assessed with immunohistochemistry, Western blot and qPCR. Key results: Chronic low-dose treatment with LSL60101 and donepezil reversed cognitive deficits and impaired social behaviour. LSL60101 treatment did not affect anxiety-like behaviour in contrast to donepezil. In the 5XFAD brains, LSL60101 and donepezil/LSL60101 treatments decreased Aβ-pathology and Tau hyperphosphorylation, and these alterations were accompanied by decreased microglia marker Iba-1 levels and increased Trem2 gene expression. LSL60601 and donepezil decreased glial fibrillary acidic protein (GFAP) astrocytic marker reactivity. However, only LSL60601 treatment significantly increased the levels of the synaptic markers post-density 95 (PSD95) and synaptophysin (SYN). Conclusion and implications: Our results suggest that chronic low dose treatment with selective I2-IR ligands can be an effective treatment for AD and provide insights into combination treatments of symptomatic and disease-modifying drugs

Metabolic pathways have emerged as cornerstones in carcinogenic deregulation providing new therapeutic strategies for cancer management. This is illustrated by the recent discovery of a cholesterol metabolic branch involving the biochemical transformation of 5,6-epoxycholesterol (5,6-ECs). 5,6-ECs have been shown to be differentially metabolized in breast cancers (BC) compared to normal breast tissue. 5,6-ECs are metabolized into the tumour promoter oncosterone in BC, while they are transformed into the tumour suppressor metabolite dendrogenin A (DDA) in normal breast tissue. Blocking oncosterone’s mitogenic and invasive potential will represent new opportunities for BC treatment. The reactivation of DDA biosynthesis, or its use as a drug, represents promising therapeutic approaches such as DDA-deficiency complementation, activation of BC cell re-differentiation and BC chemoprevention. This review presents current knowledge as to the 5,6-EC metabolic pathway in BC focusing on the 5,6-EC metabolic enzymes ChEH and HSD11B2, and on 5,6-EC metabolite targets LXRβ and GR.

Pyroptosis, is a specialized form of inflammatory cell death which aids the defensive response against invading pathogens. Its tight regulation is lost during infection by the severe acute respiratory coronavirus 2 (SARS-CoV-2) and thus uncontrolled pyroptosis disrupts the immune system and the integrity of organs defining the critical conditions in patients with high viral load. Molecular pathways engaged downstream to the formation and stabilization of the inflammasome -required to execute the process- have been uncovered and drugs are available for their regulation. On the contrary, pharmacological inferring of the upstream events -which are critical to sense and interpret the initial damage by the pathogen- is far from being elucidated. This limits our capacity to identify early markers and targets to ameliorate SARS-CoV-2 linked pyroptosis. Here we aim to raise attention on mitochondria and pathways leading to its dysfunction with the goal to inform early steps of inflammasome and devise tools to interpret and counteract diseases by the SARS-CoV-2.

Na+,K+ATPase (NKA), a transmembrane protein essential for maintaining the electrochemical gradient across the plasma membrane, acts as a receptor for cardiotonic steroids (CTS) such as ouabain. CTS binding to NKA, triggers signalling pathways or inhibits NKA activity in a concentration-dependent manner, resulting in a modulation of Ca2+ levels, which are essential for homeostasis in neurons. However, most of the pharmacological strategies for avoiding neuronal death do not target NKA activity, due to its complexity and poor comprehension of the mechanisms involved in NKA modulation. The present review aims to discuss two points regarding the interplay between NKA and Ca2+ signalling in the brain: NKA impairment causing illness as well as neuronal death due to Ca2+ signalling and benefits to the brain by modulating NKA activity. These interactions play an essential role in neuronal cell fate determination and are relevant to finding new targets for the treatment of neurodegenerative diseases.

Background and Purpose: Cancer cachexia and cancer-associated thrombosis are potentially fatal outcomes of advanced cancer. Nevertheless, thrombin expression in NSCLC primary tumor tissues and the association between prognosis of NSCLC patients remain largely unknown. Experimental Approach: Clinical pathological analysis was performed to determine the relationship between thrombin and tumor progression. Effect of r-hirudin and DTIP on cancer progression were evaluated. Western blotting, immunohistochemistry, and immunofluorescence were used to explore the inhibition mechanism of r-hirudin and DTIP. Therapeutic effect of combination of DTIP and chemotherapy was determined. Key Results: We illustrated thrombin expression in NSCLC tissues is closely related to clinicopathological features and the prognosis of patients. Thrombin deficiency inhibited tumor progression. The novel thrombin inhibitors, r-hirudin and DTIP, inhibited cell invasion and metastasis in vitro. They inhibited tumor growth and metastasis in orthotopic lung cancer model; inhibited cells invasion and prolonged survival after injection tumor cells via tail vein; they also inhibited angiogenesis and spontaneous metastases from subcutaneously inoculated tumors. The promotional activity of thrombin in invasion and metastasis was abolished in PAR-1 deficient-NSCLC cells. r-hirudin and DTIP inhibit tumor progression through the thrombin-PAR-1-mediated RhoA and NF-κB signaling cascades via inhibiting the MMP9 and IL6 expression. DTIP potentiated chemotherapy-induced growth and metastatic inhibition and inhibited chemotherapy-induced resistance in mice. Conclusions and Implications: Thrombin makes a substantial contribution, together with PAR-1, to NSCLC malignancy. We concluded the anticoagulants, r-hirudin and DTIP, could be expanded for anti-tumor therap. Combination therapy of DTIP and chemotherapy might achieve a better therapeutic effect.

Background and Purpose Vancomycin is one of the most common antibiotics administered in the hospital setting, yet acute kidney injury is a major limiting factor. Common combinations of antibiotics with vancomycin have been reported to worsen and improve vancomycin-induced kidney injury. We aimed to study the impact of flucloxacillin and imipenem-cilastatin on kidney injury when combined with vancomycin in our translational rat model. Experimental Approach Male Sprague-Dawley rats received allometrically scaled (1) vancomycin (2) flucloxacillin, (3) vancomycin+flucloxacillin, (4) vancomycin+imipenem-cilastatin, or (5) saline for 4 days. Vancomycin was administered intravenously and flucloxacillin or imipenem-cilastatin were administered intraperitoneally. Kidney injury was evaluated via drug accumulation and urinary biomarkers including urinary output, kidney injury molecule-1 (KIM-1), clusterin, and osteopontin. Relationships between vancomycin accumulation in the kidney and urinary kidney injury biomarkers were explored. Key Results Urinary output increased every study day for vancomycin+flucloxacillin; whereas in the vancomycin group it was elevated after the first dose only. In the vancomycin+flucloxacillin group, urinary KIM-1/24h increased on all days compared to vancomycin. In the vancomycin+imipenem-cilastatin group, urinary KIM-1/24h was decreased on days 1 and 2 compared to vancomycin. Similar trends were observed for clusterin. More vancomycin accumulated in the kidney with vancomycin+flucloxacillin compared to vancomycin and vancomycin+imipenem-cilastatin. The accumulation of vancomycin in the kidney tissue correlated with increasing urinary KIM-1 (4-parameter Hill Slope, R2=0.7985). Conclusion and Implications Vancomycin+flucloxacillin caused more kidney injury compared to vancomycin alone and vancomycin+imipenem-cilastatin in a translational rat model as determined by multiple kidney injury biomarkers. The combination of vancomycin+imipenem-cilastatin was nephroprotective.

Schizophrenia remains a sizable socioeconomic burden that continues to be treated with therapeutics based on 70-year old science. All currently approved therapeutics primarily target the dopamine D2 receptor to achieve their efficacy. Whilst dopaminergic dysregulation is a key feature in this disorder, the targeting of dopaminergic machinery has yielded limited efficacy and an appreciable side effect burden. Over the recent decades, numerous drugs that engage non-dopaminergic GPCRs have yielded a promise of efficacy without the deleterious side effect profile, yet none have successfully completed clinical studies and progressed to the market. More recently, there has been increased attention around non-dopaminergic GPCR-targeting drugs, notably KarXT, which demonstrated efficacy in some schizophrenia symptom domains. This provides renewed hope that effective schizophrenia may lay outside of the dopaminergic space. Despite the potential for muscarinic receptor- (and other well-characterised GPCR families) targeting drugs to treat schizophrenia, they are often plagued with complications such as lack of receptor subtype selectivity and peripheral on-target side-effects. Orphan GPCR studies have opened a new avenue of exploration with many demonstrating schizophrenia-relevant mechanisms and a favourable expression profile, thus offering potential for novel drug development. This review discusses centrally-expressed orphan G protein-coupled receptors: GPR3, GPR6, GPR12, GPR52, GPR85, GPR88 and GPR139 and their relationship to schizophrenia. We review their expression, signalling mechanisms and cellular function, in conjunction with small molecule development and structural insights. We seek to provide a snapshot of the growing evidence and development potential of new classes of schizophrenia therapeutics.

Many Western countries have been affected by the outbreak of COVID-19. Italy has been particularly hit at the beginning of the pandemic, immediately after China. In Italy and elsewhere women seem to be less affected then men by severe/fatal COVID-19 infection, regardless of their age. Despite the evidence that women and men are different fort this infection, very few studies consider different therapeutic approaches for the two sexes. Undoubtedly, understanding the mechanisms at the bases of these differences may help to find appropriate and sex specific therapies. Here we consider that other mechanisms but estrogen protection are involved. Several X-linked genes (such as ACE2) and Y-linked genes (SRY, SOX9) may explain sex differences. Cardiovascular comorbidities are among the major enhancers of virus lethality. In addition, the number of sex-independent non-genetic factors that can change susceptibility and mortality is enormous, and many other factors are likely to be considered, including gender and cultural habits in different countries.

Background and Purpose: Liver fibrosis is one of the leading causes of morbidity and mortality worldwide of which no acceptable therapy exists. Accumulating evidence supports that glioma-associated oncogene homologue 1(GLI1) is a potentially important therapeutic target for liver fibrosis. This study investigates the antifibrotic activities and potential mechanisms of Physalin B (PB), a natural Solanaceae compound. Experimental Approach: Mice subjected to CCl4 challenge and bile duct ligation were used to study the antifibrotic effects of PB in vivo. Mouse primary hepatic stellate cells (pHSCs) and human HSC line LX‐2 also served as an in vitro liver fibrosis model. Liver fibrogenic genes, GLI1 downstream genes were examined using western blot and real-time PCR analyses. GLI1 acetylation and LAP2α-HDAC1 interaction were analyzed by coimmunoprecipitation. Key Results: In animal models, PB administration attenuated hepatic histopathological injury, collagen accumulation, and reduced the expression of fibrogenic genes. PB dose‐dependently suppressed fibrotic marker expression in LX‐2 cells and mouse pHSCs. Mechanistic studies showed PB inhibited GLI activity in a non-canonical Hedgehog signaling. PB blocked lamina-associated polypeptide 2 α (LAP2α)/ histone deacetylase 1 (HDAC1) complex formation thereby inhibited HDAC1mediated GLI1 deacetylation. PB downregulated the acetylation and expression of GLI1, and subsequently inhibiting HSC activation. Conclusions and Implications: PB exerted potent antifibrotic effects in vitro and in vivo by disrupting the LAP2α/HDAC1 complex, increasing GLI1 acetylation and inactivating GLI1. This indicates that PB may be a potential therapeutic candidate for the treatment of liver fibrosis.

Muscle protein catabolism in patients with diabetic nephropathy (DN) results in striking losses of muscle proteins, which increases morbidity and mortality risks. Emerging evidence shows that short-chain fatty acids (SCFAs) play an important role in the maintenance of health and disease development. Recently, the connection between butyrate (a SCFA) and DN has been revealed, although the relationship between butyrate and muscle atrophy is still not clear. In our study, we found a significant decrease in butyrate in DN using metabolomics analyses. The addition of butyrate remarkably intestinal barrier function. Concurrently, butyrate could alleviate muscle atrophy and promote PI3K/AKT/mTOR signals, and suppress oxidative stress and autophagy in the skeletal muscle of db/db mice as well as high glucose/lipopolysaccharide (HG/LPS)-induced C2C12 cells. To further explore the mechanism, we found that GPR43, the key SCFAs signaling molecule, was significantly decreased in the skeletal muscle of db/db mice and HG/LPS-induced C2C12 cells. Overexpression of GPR43 could activate PI3K/AKT/mTOR signals and inhibit oxidative stress and autophagy in HG/LPS-induced C2C12 cells. Silencing of GPR43 blocked PI3K/AKT/mTOR signals improved by butyrate, as well as suppression of oxidative stress and reduction of autophagy. Ultimately, butyrate alleviated muscle atrophy in DN via GPR43-mediated PI3K/AKT/mTOR pathway

Fungal infections cause serious problems in many aspects of human life; especially infections by fungal species represent problems in immunocompromised patients. Current antifungal antibiotics target various metabolic pathways, predominantly the cell wall or cellular membrane. However, numerous compounds are available to combat fungal infections, their efficacy is far from being satisfactory and some of them display substantial toxicity. The emerging resistance represents a serious issue as well; thus, there is a considerable need for new anti-fungal compounds with lower toxicity and higher effectiveness. One of the unique antifungal antibiotics is sordarin, the only known compound that acts on the fungal translational machinery per se. It has been shown that sordarin inhibits protein synthesis at the elongation step of the translational cycle, acting on eukaryotic elongation-factor-2. In this review, we are aiming to deliver a robust scientific platform promoting the development of antifungal compounds, especially focusing on molecular action of sordarin.

Skin drug delivery is an emerging route in the drug development, due to its great advantages, thus leading to an urgent need to understand the behaviour of active pharmaceutical ingredients into/through the skin. This knowledge is crucial in the early stages of product design and development. Yet, given the skin barrier properties as one of the first body’s natural defence systems, it can act as an obstacle to the successful outcome of a skin drug therapy. To unravel the mechanisms underlying this barrier, reductionist strategies have designed several models with different levels of complexity and integrity, using non-biological and biological components. Besides the detail of information and resemblance to the in vivo Human skin that each in vitro model offers, the technical and economic efforts required should be considered when selecting the most adequate model for the intended research. This review provides an outline of the most commonly applied skin models, including healthy and diseased conditions, lab developed systems and commercialized models, their advantages and limitations and, also an overview of the new trends in skin engineered models.

Brain mineralocorticoid receptors (MR) mediate effects of aldosterone in relation to salt homeostasis, and of glucocorticoid stress hormones corticosteroids in the context of stress adaptation. Brain stem MRs respond to aldosterone, while forebrain MRs mediate rapid and delayed MR-mediated glucocorticoids effects in conjunction with the glucocorticoid receptor. MR-mediated effects depend on gender, genetic variations and environmental influences. Disturbed MR activity by chronic stress or in certain (endocrine) diseases can cause deleterious effects on affective state, cognitive and behavioural function in susceptible individuals. High MR activation may have protective effects in healthy individuals, whereas dysregulated high MR activity during a stress response would require treatment with mineralocorticoid receptor antagonists (MRAs). Here, we discuss recent pharmacological and genetic developments, from the molecular underpinnings of MR signaling and function, to pharmacological interventions in the clinic. Improved understanding of MR dependent pathways will help to improve glucocorticoid therapy, unwanted side effects and psychiatric symptoms.

Lopinavir combined with ritonavir were reported to benefit the patients with SARS by reducing the viral loads. However, in the latest clinical trials, no benefit was observed with lopinavir-ritonavir treatment beyond standard care in patients with COVID-19. We comment here that this disappointed result of clinical trial might result from the low volume of the lung distribution of lopinavir. The major reasons were listed below: 1) The binding affinity of ACE2 with SARS-CoV-2 spike protein is ~10- to 20-fold higher than the binding affinity of ACE2 with SARS-CoV spike protein, indicating that SARS-CoV-2 can enter AT2 cells in lung much easier than SARS-CoV. Therefore, the viral loads of SARS-CoV-2 might be much higher than viral loads of SARS-CoV in the lung tissue. 2) The concentration of lopinavir in the lung tissue was 1.18 μg equiv/ml in rats. The low volume of the lung distribution of lopinavir might not be enough to inhibit the coronavirus replication due to the high viral loads in the lung tissue. 3) In contrast, the concentration of chloroquine in the lung tissue was much higher (30.76 ± 0.85 μg equiv/ml) in rats, which might lead to its clinical and virologic benefits in the treatment of COVID-19 patients. Together, we proposed here that anti-SARS-CoV-2 drug repurposing studies should pay more attentions to the lung tissue distribution of antiviral drugs. The efficacy of antiviral drugs might depend on their lung tissue distributions

Background and Purpose The cyclic nucleotides cAMP and cGMP are ubiquitous second messengers participating in the regulation of several biological processes. Interference of cNMP signalling is linked to multiple diseases and thus is an important component of pharmaceutical research. The existing optogenetic toolbox in C. elegans is restricted to soluble adenylyl cyclases, the membrane-bound Blastocladiella CyclOp and hyperpolarizing rhodopsins, yet missing are membrane-bound photoactivatable adenylyl cyclases and hyperpolarizers on the basis of K+-currents. Experimental Approach For the characterization of the photoactivatable nucleotidyl cyclases, we expressed the proteins alone or in combination with cyclic-nucleotide gated channels in C. elegans muscle cells and cholinergic motor neurons. To investigate the extent of optogenetic cNMP production and the ability of the systems to de- or hyperpolarize the cells, we performed behavioural analyses (locomotion, muscle contraction) and measured the cNMP content in vitro. Key Results We implemented Catenaria CyclOp as a new tool for cGMP production, allowing fine-control of cGMP levels. As photoactivatable membrane-bound adenylyl cyclases, we established YFP::BeCyclOp(A-2x) and YFP::CaCyclOp(A-2x), enabling more specific optogenetic cAMP signalling compared to soluble ACs. For the hyperpolarization of excitable cells by K+-currents, we introduced the cAMP-gated K+-channel SthK from Spirochaeta thermophila with either bPAC or BeCyclOp(A-2x), and the Blastocladiella emersonii cGMP-gated K+-channel BeCNG1 with BeCyclOp. Conclusion and Implications We established a comprehensive suite of optogenetic tools for cNMP manipulation for the nematode, which will be useful for applications in many cell types, including sensory neurons which use mainly cGMP as second messenger, and for potent hyperpolarization using K+-ions.

As human spaceflight continues with extended mission durations, the demand of effective and safe drugs is going to increase. To date, the medications used during missions (for space motion sickness, sleep disturbances, allergies, pain and sinus congestion) are administered under the assumption that they act similarly as on the Earth. During spaceflights however fluid shifts, muscle and bone loss, immune system dysregulation and changes in the gastrointestinal tract and metabolism are documented. These alterations may change the pharmacokinetics (PK) and pharmacodynamics. The information gained from bed-rest studies and from inflight observations is partial and demonstrates variability in drug PK. The objectives of this review are to report: i) the impact of the space environmental stressors on human physiology in relation to PK; ii) the state-of-the-art on experimental data in space and/or in ground-based models; iii) the validation of ground-based models for PK studies; and iv) the identification of possible research gaps.