Continuous regional arterial infusion versus intravenous administration of the protease inhibitor nafamostat mesilate for predicted severe acute pancreatitis: a multicenter, randomized, open-label, phase 2 trial

Nafamostat Reduces the Incidence of post-ERCP Pancreatitis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). As the management of pancreatitis is limited, clinical approaches focus on the prevention of post-ERCP pancreatitis (PEP). In theory, the serine protease inhibitor nafamostat can reduce circulating inflammatory mediators in pancreatitis. We aimed to investigate the effect of nafamostat in the prevention of PEP in this systematic review and meta-analysis. The protocol for this review was registered in PROSPERO (CRD42022367988). We systematically searched 5 databases without any filters on September 26, 2022. The eligible population was adult patients undergoing ERCP. We compared the PEP preventive effect of nafamostat to placebo. The main outcome was the occurrence of PEP. We calculated the pooled odds ratios (ORs), mean differences, and corresponding 95% confidence intervals (95% CIs) and multilevel model. The risk of bias was assessed using the Rob2 tool. Seven randomized controlled trials involving 2,962 patients were eligible for inclusion. Nafamostat reduced the overall incidence rate of PEP (20 mg, OR: 0.50, 95% CI: 0.30-0.82 and 50 mg, OR: 0.48, 95% CI: 0.24-0.96). However, the occurrence of mild PEP was significantly reduced only in the subgroup receiving 20 mg nafamostat (OR, 0.49, 95% CI: 0.31-0.77). Overall, nafamostat therapy reduced moderate PEP in high-risk patients (OR: 0.18, 95% CI: 0.0.4-0.84) and mild PEP in low-risk patients (OR: 0.32, 95% CI: 0.17-0.61). Nafamostat is an effective therapy in the prevention of mild post-ERCP pancreatitis. Further research is required to determine the cost-effectiveness of this therapy.

No role for protease inhibitors as a mitigation strategy for postpancreatectomy acute pancreatitis (PPAP): Propensity score matching analysis

BACKGROUND

While the use of protease inhibitor gabexate mesylate (GM) is still controversial in acute pancreatitis, it has never been tested for postpancreatectomy acute pancreatitis (PPAP). This study aims to assess the impact of GM on postoperative serum hyperamylasaemia (POH) or PPAP after pancreatoduodenectomy (PD).

METHODS

Consecutive patients developing POH after PD between 2016 and 2021 were included. According to GM administration, patients were divided into GM-treated and control (CTR) groups. GM was administered from postoperative day 1-3 in POH patients who underwent surgery before 2017. A 2:1 propensity matching was used to minimize the risk of bias.

RESULTS

Overall, 264 patients with POH were stratified in the GM (59 patients) and CTR (104 patients) cohorts, which showed balanced baseline characteristics after matching. No difference in postoperative complications was observed between the groups (all p > 0.05), except for PPAP occurrence, which was significantly higher in the GM group (37% vs. 22%, p = 0.037). A total of 45 patients (28%) evolved to PPAP. Comparing PPAP patients in the GM and CTR groups, no significant differences in POPF, relaparotomy, and mortality (all p > 0.09) were found. No difference in intravenous crystalloid administration was found in patients with PPAP, whether or not they developed major complications or pancreatic fistula (p > 0.05) CONCLUSION: Protease inhibitor seems ineffective in preventing a PPAP after PD once a POH has occurred. Further studies are needed to achieve benchmarks for treating PPAP and identify mitigation strategies to prevent the evolution of POH into additional morbidity.

A Randomized Trial of Nafamostat for Covid-19

A Randomized Trial of Nafamostat for Covid-19Nafamostat mesylate is a potent in vitro antiviral that inhibits the host transmembrane protease serine 2 enzyme used by SARS-CoV-2 for cell entry. Morpeth et al report the results of an open-label randomized clinical trial of nafamostat for noncritically ill patients with Covid-19.

Acute Pancreatitis Review

Acute pancreatitis, a prevalent illness with devastating consequences, poses a grave threat to those affected. There has been a steady increase in the occurrence of acute pancreatitis at about 3% per year from 1961 to 2016. There are 3 main guidelines on acute pancreatitis, including the American College of Gastroenterology, the International Association of Pancreatology/American Pancreatic Association guideline in 2013, and the American Gastroenterological Association guideline in 2018. However, several milestone studies have been published since then. We hereby reviewed the current acute pancreatitis guidelines with an update on clinical practicechanging literature. The aggressive or moderate fluid resuscitation in acute pancreatitis (WATERFALL) trial recommended fluid resuscitation with lactated Ringer's solution at a moderate aggressive rate. All guidelines did not recommend prophylactic antibiotics use. Early enteral feeding reduces morbidity. A clear liquid diet is no longer recommended. Nutrition with nasogastric or nasojejunal feeding does not have a difference. The upcoming high vs. low-energy administration in the early phase of acute pancreatitis (GOULASH) trial will provide more information on the impact of calorie intake. Pain management should be individualized based on the degree of pain and severity of pancreatitis. In patients with moderate to severe and severe acute pancreatitis, a step-down approach with epidural analgesia can be considered for moderate to severe pain. The management of acute pancreatitis has evolved. New research on the impact of electrolytes, pharmacologic agents, the role of anticoagulants, and nutrition support will provide scientific and clinical evidence to improve patient care and decrease morbidity and mortality.

Potential treatments of COVID-19: Drug repurposing and therapeutic interventions

The coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The infection is caused when Spike-protein (S-protein) present on the surface of SARS-CoV-2 interacts with human cell surface receptor, Angiotensin-converting enzyme 2 (ACE2). This binding facilitates SARS-CoV-2 genome entry into the human cells, which in turn causes infection. Since the beginning of the pandemic, many different therapies have been developed to combat COVID-19, including treatment and prevention. This review is focused on the currently adapted and certain other potential therapies for COVID-19 treatment, which include drug repurposing, vaccines and drug-free therapies. The efficacy of various treatment options is constantly being tested through clinical trials and in vivo studies before they are made medically available to the public.

Controversies in the management of acute pancreatitis: An update

This review summarized the current controversies in the management of acute pancreatitis (AP). The controversies in management range from issues involving fluid resuscitation, nutrition, the role of antibiotics and antifungals, which analgesic to use, role of anticoagulation and intervention for complications in AP. The interventions vary from percutaneous drainage, endoscopy or surgery. Active research and emerging data are helping to formulate better guidelines. The available evidence favors crystalloids, although the choice and type of fluid resuscitation is an area of dynamic research. The nutrition aspect does not have controversy as of now as early enteral feeding is preferred most often than not. The empirical use of antibiotics and antifungals are gray zones, and more data is needed for conclusive guidelines. The choice of analgesic is being studied, and the recommendations are still evolving. The position of using anticoagulation is still awaiting consensus. The role of intervention is well established, although the modality is constantly changing and favoring endoscopy or percutaneous drainage rather than surgery. It is evident that more multicenter randomized controlled trials are required for establishing the standard of care in these crucial management issues of AP to improve the morbidity and mortality worldwide.

Predicting the systemic exposure and lung concentration of nafamostat using physiologically-based pharmacokinetic modeling

Nafamostat has been actively studied for its neuroprotective activity and effect on various indications, such as coronavirus disease 2019 (COVID-19). Nafamostat has low water solubility at a specific pH and is rapidly metabolized in the blood. Therefore, it is administered only intravenously, and its distribution is not well known. The main purposes of this study are to predict and evaluate the pharmacokinetic (PK) profiles of nafamostat in a virtual healthy population under various dosing regimens. The most important parameters were assessed using a physiologically based pharmacokinetic (PBPK) approach and global sensitivity analysis with the Sobol sensitivity analysis. A PBPK model was constructed using the SimCYP^® simulator. Data regarding the in vitro metabolism and clinical studies were extracted from the literature to assess the predicted results. The model was verified using the arithmetic mean maximum concentration (C_max), the area under the curve from 0 to the last time point (AUC_0-t), and AUC from 0 to infinity (AUC_0-∞) ratio (predicted/observed), which were included in the 2-fold range. The simulation results suggested that the 2 dosing regimens for the treatment of COVID-19 used in the case reports could maintain the proposed effective concentration for inhibiting severe acute respiratory syndrome coronavirus 2 entry into the plasma and lung tissue. Global sensitivity analysis indicated that hematocrit, plasma half-life, and microsomal protein levels significantly influenced the systematic exposure prediction of nafamostat. Therefore, the PBPK modeling approach is valuable in predicting the PK profile and designing an appropriate dosage regimen.

Preclinical testing of dabigatran in trypsin-dependent pancreatitis

Pancreatitis, the inflammatory disorder of the pancreas, has no specific therapy. Genetic, biochemical, and animal model studies revealed that trypsin plays a central role in the onset and progression of pancreatitis. Here, we performed biochemical and preclinical mouse experiments to offer proof of concept that orally administered dabigatran etexilate can inhibit pancreatic trypsins and shows therapeutic efficacy in trypsin-dependent pancreatitis. We found that dabigatran competitively inhibited all human and mouse trypsin isoforms (Ki range 10-79 nM) and dabigatran plasma concentrations in mice given oral dabigatran etexilate well exceeded the Ki of trypsin inhibition. In the T7K24R trypsinogen mutant mouse model, a single oral gavage of dabigatran etexilate was effective against cerulein-induced progressive pancreatitis, with a high degree of histological normalization. In contrast, spontaneous pancreatitis in T7D23A mice, which carry a more aggressive trypsinogen mutation, was not ameliorated by dabigatran etexilate, given either as daily gavages or by mixing it with solid chow. Taken together, our observations showed that benzamidine derivatives such as dabigatran are potent trypsin inhibitors and show therapeutic activity against trypsin-dependent pancreatitis in T7K24R mice. Lack of efficacy in T7D23A mice is probably related to the more severe pathology and insufficient drug concentrations in the pancreas.

Molecular mechanisms involved in anosmia induced by SARS-CoV-2, with a focus on the transmembrane serine protease TMPRSS2

Since 2020, SARS-CoV-2 has caused a pandemic virus that has posed many challenges worldwide. Infection with this virus can result in a number of symptoms, one of which is anosmia. Olfactory dysfunction can be a temporary or long-term viral complication caused by a disorder of the olfactory neuroepithelium. Processes such as inflammation, apoptosis, and neuronal damage are involved in the development of SARS-CoV-2-induced anosmia. One of the receptors that play a key role in the entry of SARS-CoV-2 into the host cell is the transmembrane serine protease TMPRSS2, which facilitates this process by cleaving the viral S protein. The gene encoding TMPRSS2 is located on chromosome 21. It contains 15 exons and has many genetic variations, some of which increase the risk of disease. Delta strains have been shown to be more dependent on TMPRSS2 for cell entry than Omicron strains. Blockade of this receptor by serine protease inhibitors such as camostat and nafamostat can be helpful for treating SARS-CoV-2 symptoms, including anosmia. Proper understanding of the different functional aspects of this serine protease can help to overcome the therapeutic challenges of SARS-CoV-2 symptoms, including anosmia. In this review, we describe the cellular and molecular events involved in anosmia induced by SARS-CoV-2 with a focus on the function of the TMPRSS2 receptor.

Effects of nitroglycerin combined with continuous regional arterial infusion on severe acute pancreatitis, triglyceride, inflammatory factors and prognosis

Background: To evaluate the effects of nitroglycerin combined with continuous regional arterial infusion (CRAI) on severe acute pancreatitis (SAP), triglyceride (TG), inflammatory factors and prognosis.

Methods: SAP patients were randomly divided into control and observation groups (n=169). The control group was treated with intravenous infusion of nitroglycerin once daily for 2 d, while the observation group was treated with nitroglycerin combined with CRAI for 7 d. Their hospitalization time, abdominal pain relief time, abdominal distension relief time and intestinal function recovery time were recorded. The levels of inflammatory factors, and TG were measured. Their liver and kidney functions, hemorheological indices, prognosis, and adverse reactions were evaluated.

Results: The observation group had significantly shorter hospitalization time, abdominal pain relief time, abdominal distension relief time, and intestinal function recovery time than those of the control group (P<0.05). After treatment, the levels of interleukin-6, tumor necrosis factor-alpha, endothelin, thromboxane A2 and TG significantly decreased in contrast with those before treatment in both groups, especially in the observation group (P<0.05). The hemorheological indices were significantly improved after treatment compared with those before treatment in both groups, and the observation group had better indices (P<0.05). The Acute Physiology and Chronic Health Evaluation-II score declined significantly in both groups after treatment, and the observation group had a more obvious decrease (P<0.05). During follow-up, similar incidence rates of adverse reactions were observed for both groups (P>0.05).

Conclusion: Nitroglycerin combined with CRAI is prominently effective for treating SAP, which can facilitate the health recovery and reduce the incidence of microcirculation disturbance-induced adverse events such as organ failure.

Use of nafamostat mesilate for anticoagulation during extracorporeal membrane oxygenation: A systematic review

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) represents an advanced option for supporting refractory respiratory and/or cardiac failure. Systemic anticoagulation with unfractionated heparin (UFH) is routinely used. However, patients with bleeding risk and/or heparin-related side effects may necessitate alternative strategies: among these, nafamostat mesilate (NM) has been reported.

METHODS

We conducted a systematic literature search (PubMed and EMBASE, updated 12/08/2021), including all studies reporting NM anticoagulation for ECMO. We focused on reasons for starting NM, its dose and the anticoagulation monitoring approach, the incidence of bleeding/thrombosis complications, the NM-related side effects, ECMO weaning, and mortality.

RESULTS

The search revealed 11 relevant findings, all with retrospective design. Of these, three large studies reported a control group receiving UFH, the other were case series (n = 3) or case reports (n = 5). The main reason reported for NM use was an ongoing or high risk of bleeding. The NM dose varied largely as did the anticoagulation monitoring approach. The average NM dose ranged from 0.46 to 0.67 mg/kg/h, but two groups of authors reported larger doses when monitoring anticoagulation with ACT. Conflicting findings were found on bleeding and thrombosis. The only NM-related side effect was hyperkalemia (n = 2 studies) with an incidence of 15%-18% in patients anticoagulated with NM. Weaning and survival varied across studies.

CONCLUSION

Anticoagulation with NM in ECMO has not been prospectively studied. While several centers have experience with this approach in high-risk patients, prospective studies are warranted to establish the optimal space of this approach in ECMO.

JPN clinical practice guidelines 2021 with easy-to-understand explanations for the management of acute pancreatitis

BACKGROUND

In preparing the Japanese (JPN) guidelines for the management of acute pancreatitis 2021, the committee focused the issues raised by the results of nationwide epidemiological survey in 2016 in Japan METHOD: In addition to a systematic search using the previous JPN guidelines, papers published from January 2014 to September 2019 were searched for the contents to be covered by the guidelines based on the concept of GRADE system.

RESULTS

Thirty-six clinical questions (CQ) were prepared in 15 subject areas. Base on the facts that patients diagnosed with severe disease by both Japanese prognostic factor score and contrast-enhanced CT grade had a high fatality rate and that little prognosis improvement after 2 weeks of disease onset was not obtained, we emphasized the importance of Pancreatitis Bundles, which was shown to be effective in improving prognosis, and the CQ sections for local pancreatic complications had been expanded to ensure adoption of a step-up approach. Furthermore, on the facts that enteral nutrition for severe acute pancreatitis was not started early within 48 hours of admission and that unnecessary prophylactic antibiotics was used in almost all cases, we emphasized early enteral nutrition in small amounts even if gastric feeding is used and no prophylactic antibiotics in mild pancreatitis.

CONCLUSION

All the members of the committee have put a lot of effort into preparing the extensively revised guidelines in the hope that more people will have a common understanding and that better medical care will be spread.

Co-Spray Dried Nafamostat Mesylate with Lecithin and Mannitol as Respirable Microparticles for Targeted Pulmonary Delivery: Pharmacokinetics and Lung Distribution in Rats

Coronavirus disease 2019 (COVID-19), caused by a new strain of coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is spreading rapidly worldwide. Nafamostat mesylate (NFM) suppresses transmembrane serine protease 2 and SARS-CoV-2 S protein-mediated fusion. In this study, pharmacokinetics and lung distribution of NFM, administered via intravenous and intratracheal routes, were determined using high performance liquid chromatography analysis of blood plasma, lung lumen using bronchoalveolar lavage fluid, and lung tissue. Intratracheal administration had higher drug delivery and longer residual time in the lung lumen and tissue, which are the main sites of action, than intravenous administration. We confirmed the effect of lecithin as a stabilizer through an ex vivo stability test. Lecithin acts as an inhibitor of carboxylesterase and delays NFM decomposition. We prepared inhalable microparticles with NFM, lecithin, and mannitol via the co-spray method. The formulation prepared using an NFM:lecithin:mannitol ratio of 1:1:100 had a small particle size and excellent aerodynamic performance. Spray dried microparticles containing NFM, lecithin, and mannitol (1:1:100) had the longest residual time in the lung tissue. In conclusion, NFM-inhalable microparticles were prepared and confirmed to be delivered into the respiratory tract, such as lung lumen and lung tissue, through in vitro and in vivo evaluations.

Severe necrotizing pancreatitis immediately after non-abdominal surgery under general anesthesia with propofol

Postoperative pancreatitis is a relatively rare disease and is poorly recognized. Herein, we present a case of necrotizing pancreatitis that developed immediately after non-abdominal surgery under general anesthesia. In this report, 4 h after thyroidectomy under general anesthesia using propofol, the patient developed upper abdominal pain and was diagnosed with severe acute pancreatitis with extensive pancreatic necrosis. Immediately after the diagnosis, the patient received appropriate treatment, and acute pancreatitis was improved. Subsequently, the patient has the formation of non-infectious giant walled-off necrosis and remained in good condition without additional treatment for 1.5 years after pancreatitis onset. In this case report, our detailed causative search suggested that propofol administration could be the cause of this pancreatitis. Propofol-induced pancreatitis is extremely rare but develops often severely, resulting in fatality. In this case, the patient developed severe acute pancreatitis within a very short time after surgery but was able to survive by immediate intervention of treatment. We suggest that clinicians should consider acute pancreatitis as a life-threatening adverse event under general anesthesia with propofol and perform thorough postoperative management.

A Review on Expression, Pathological Roles, and Inhibition of TMPRSS2, the Serine Protease Responsible for SARS-CoV-2 Spike Protein Activation

SARS-CoV-2, the coronavirus responsible for the COVID-19 pandemic, uses the host cell membrane receptor angiotensin-converting enzyme 2 (ACE2) for anchoring its spike protein, and the subsequent membrane fusion process is facilitated by host membrane proteases. Recent studies have shown that transmembrane serine protease 2 (TMPRSS2), a protease known for similar role in previous coronavirus infections, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome (MERS), is responsible for the proteolytic cleavage of the SARS-CoV-2 spike protein, enabling host cell fusion of the virus. TMPRSS2 is known to be expressed in the epithelial cells of different sites including gastrointestinal, respiratory, and genitourinary system. The infection site of the SARS-CoV-2 correlates with the coexpression sites of ACE2 and TMPRSS2. Besides, age-, sex-, and comorbidity-associated variation in infection rate correlates with the expression rate of TMPRSS2 in those groups. These findings provide valid reasons for the assumption that inhibiting TMPRSS2 can have a beneficial effect in reducing the cellular entry of the virus, ultimately affecting the infection rate and case severity. Several drug development studies are going on to develop potential inhibitors of the protease, using both conventional and computational approaches. Complete understanding of the biological roles of TMPRSS2 is necessary before such therapies are applied.

Human umbilical cord-derived mesenchymal stem cells improve chronic pancreatitis in rats via the AKT-mTOR-S6K1 signaling pathway

Chronic pancreatitis (CP) is a progressive inflammatory disease. In clinical treatment, many patients cannot get a timely diagnosis and effective treatment due to the lack of early diagnosis indicators. Mesenchymal stem cells have immunomodulatory and anti-inflammatory effects, and have broad application prospects in treating auto-immune diseases and inflammatory diseases. This study aimed to clarify the mechanisms of human umbilical cord mesenchymal stem cells (HUCMSCs) in the treatment of CP. The rats were randomly divided into four groups, with six rats in each group: control group, CP group, CP + HUCMSCs-treated group I, and CP + HUCMSCs-treated group II. We evaluated the levels of inflammatory factors, fibrosis and apoptosis markers, detected the protein expression levels of AKT-mTOR-S6K1 and assessed histological changes of the pancreas. The results showed that HUCMSCs not only inhibited the secretion of inflammatory cytokines and activation of pancreatic stellate cells but also suppressed the apoptosis of acinar cells. Further investigation revealed that HUCMSCs noticeably suppressed the AKT-mTOR-S6K1 pathway in the pancreatic tissue of DBTC-induced CP. In addition, the therapeutic effect of HUCMSCs injected into the inferior vena cava and left gastric artery in the CP model was also observed, thus providing the basis for the clinical application of intervention measures.

Insights into SARS-CoV-2: Medicinal Chemistry Approaches to Combat Its Structural and Functional Biology

Coronavirus disease 2019, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still a pandemic around the world. Currently, specific antiviral drugs to control the epidemic remain deficient. Understanding the details of SARS-CoV-2 structural biology is extremely important for development of antiviral agents that will enable regulation of its life cycle. This review focuses on the structural biology and medicinal chemistry of various key proteins (Spike, ACE2, TMPRSS2, RdRp and M^pro) in the life cycle of SARS-CoV-2, as well as their inhibitors/drug candidates. Representative broad-spectrum antiviral drugs, especially those against the homologous virus SARS-CoV, are summarized with the expectation they will drive the development of effective, broad-spectrum inhibitors against coronaviruses. We are hopeful that this review will be a useful aid for discovery of novel, potent anti-SARS-CoV-2 drugs with excellent therapeutic results in the near future.

A review on the clinical trials of repurposing therapeutic drugs, mechanisms and preventive measures against SARS-CoV-2

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a highly transmittable pathogenic viral infection that causes a disease known as COVID-19. It is a pandemic and public health challenge ravaging the world today. Unfortunately, with the daily increase of infected individuals, there is no known drug approved for the treatment of COVID-19. However, there are therapeutic drugs with the potentials to inhibit endocytic pathways, suppress ribonucleic acid (RNA) polymerase activities, and reduce the replication of SARS-CoV-2. These drugs modifications are aimed at reducing inflammation, time of recovery, and number of deaths. This review is aimed at providing updated information on the clinical manifestations, diagnosis, preventive measures and therapeutic drugs used against SARS-CoV-2. The finding of this review revealed that some of these drugs are transmembrane protease, serine 2, and angiotensin-converting enzyme 2 inhibitors with the capacity to block the entrance/replication of SARS-CoV-2 in a host cell and therefore, may be promising in preventing the spread and mortality of SARS-CoV-2. However, these drugs may cause detrimental health effects such as toxic and non-efficacy issues. Therefore great caution should be employed by health professionals when prescribing these drugs to COVID-19 patients.

Inflammatory pathways and potential therapies for COVID-19: A mini review

The public health crisis of the novel coronavirus disease (COVID-19) is alarming since January 2020. COVID-19 genome (SARS-CoV-2) is related to other highly pathogenic coronaviruses SARS-CoV (severe acute respiratory syndrome coronavirus) and MERS-CoV (Middle East respiratory syndrome coronavirus). Amino acid substitutions in some of SARS-CoV-2 proteins resulted in mutations proposing more virulent and contagious properties for this novel virus. Coronavirus penetrates the host cell via endocytosis and once infected, immune responses are triggered to fight against the pathogen. Innate immune response activates major transcription factors to secrete proinflammatory cytokines and type 1 interferon response (T1INF) to induce antiviral immunity. While adaptive immunity initiates cascade of B-cells antibody mediated and T-cells cellular mediate immunities, several mechanisms are raised by SARS-CoV-2 to evade host immune response. Consequently, a surge of proinflammatory cytokines, known as cytokine storm (CS) are released. Failure to manage CS results in several pathological complications as acute respiratory distress syndrome (ARDS). Although researches have not discovered an effective treatment against SARS-CoV-2, recent therapeutic approaches recommending the use of anti-inflammatories in combination with antivirals and some repurposed drugs for COVID-19 patients. Future medications should be designed to target essential hallmarks in the CS to improve clinical outcomes.

In Silico Study of Coumarins and Quinolines Derivatives as Potent Inhibitors of SARS-CoV-2 Main Protease

The pandemic that started in Wuhan (China) in 2019 has caused a large number of deaths, and infected people around the world due to the absence of effective therapy against coronavirus 2 of the severe acute respiratory syndrome (SARS-CoV-2). Viral maturation requires the activity of the main viral protease (Mpro), so its inhibition stops the progress of the disease. To evaluate possible inhibitors, a computational model of the SARS-CoV-2 enzyme Mpro was constructed in complex with 26 synthetic ligands derived from coumarins and quinolines. Analysis of simulations of molecular dynamics and molecular docking of the models show a high affinity for the enzyme (∆E binding between -5.1 and 7.1 kcal mol-1). The six compounds with the highest affinity show K d between 6.26 × 10-6 and 17.2 × 10-6, with binding affinity between -20 and -25 kcal mol-1, with ligand efficiency less than 0.3 associated with possible inhibitory candidates. In addition to the high affinity of these compounds for SARS-CoV-2 Mpro, low toxicity is expected considering the Lipinski, Veber and Pfizer rules. Therefore, this novel study provides candidate inhibitors that would allow experimental studies which can lead to the development of new treatments for SARS-CoV-2.

Mechanistic insight into anti-COVID-19 drugs: recent trends and advancements

The Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) has been established now to be a deadly disease afflicting the whole world with worst consequences on healthcare, economy and day-to-day life activities. Being a communicable disease, which is highly pathogenic in humans, causing cough, throat infection, breathing problems, high fever, muscle pain, and may lead to death in some cases especially those having other comorbid conditions such as heart or kidney problems, and diabetes. Finding an appropriate drug and vaccine candidate against coronavirus disease (COVID-19) remains an ultimate and immediate goal for the global scientific community. Based on previous studies in the literature on SARS-CoV infection, there are a number of drugs that may inhibit the replication of SARS-CoV-2 and its infection. Such drugs comprise of inhibitors of Angiotensin-Converting Enzyme 2 (ACE2), transmembrane Serine Protease 2 (TMPRSS2), nonstructural protein 3C-like protease, nonstructural RNA-dependent RNA polymerase (RdRp) and many more. The antiviral drugs such as chloroquine and hydroxychloroquine, lopinavir and ritonavir as inhibitors for HIV protease, nucleotide analogue remdesivir, and broad-spectrum antiviral drugs are available to treat the SARS-CoV-2-infected patients. Therefore, this review article is planned to gain insight into the mechanism for blocking the entry of SARS-CoV-2, its validation, other inhibition mechanisms, and development of therapeutic drugs and vaccines against SARS-CoV-2.

Targeting host cell proteases as a potential treatment strategy to limit the spread of SARS-CoV-2 in the respiratory tract

As the death toll of Coronavirus disease 19 (COVID-19) continues to rise worldwide, it is imperative to explore novel molecular mechanisms for targeting SARS-CoV-2. Rather than looking for drugs that directly interact with key viral proteins inhibiting its replication, an alternative and possibly add-on approach is to dismantle the host cell machinery that enables the virus to infect the host cell and spread from one cell to another. Excellent examples of such machinery are host cell proteases whose role in viral pathogenesis has been demonstrated in numerous coronaviruses. In this review, we propose two therapeutic modalities to tackle SARS-CoV-2 infections; the first is to transcriptionally modulate the expression of cellular proteases and their endogenous inhibitors and the second is to directly inhibit their enzymatic activity. We present a nonexhaustive collection of clinically investigated drugs that act by one of these mechanisms and thus represent promising candidates for preclinical in vitro testing and hopefully clinical testing in COVID-19 patients.

Experimental Pharmacotherapy for COVID-19: The Latest Advances

The coronavirus infectious disease-2019 (COVID-19) has overwhelmed like a shock wave in a completely unprepared world. Despite coronavirus infections were involved in previous epidemic outbreaks, no antiviral agent was developed for specific treatment. As a consequence, since the beginning of this pandemic, both repositioned and experimental drugs were used to treat the infected patients without evidence of clinical efficacy. Just based on experience coming from the use of antiviral agents to treat other viruses (eg, lopinavir/ritonavir, remdesivir) and supposed antiviral or immunomodulatory activities of drugs with no approved antiviral indications (eg hydroxychloroquine, tocilizumab), clinicians have faced the ongoing pandemic. Currently, after about 9 months from the COVID-19 spread, there is still no antiviral agent capable of ensuring the cure of this syndrome. Clinical trials are beginning to confirm the benefits of some drugs, while for other compounds, efficacy and safety have not yet been confirmed. Randomized clinical trials (RCT) have denied or downsized the beneficial effects attributed to certain molecules, such as aminoquinolines, largely used in clinical practice at the beginning of COVID-19 spread. Conversely, at the same time, they have provided evidence for unexpected effectiveness of other agents that have been underutilized, such as steroids, which were not used in SARS treatment because of the threatened effect on viral replication. Evidence deriving from pathologic studies have demonstrated that the prothrombotic effects of SARS-CoV-2 can be prevented by heparin prophylaxis, underlining the need for personalized treatment for patients with severe disease. The main aim of this review is to synthesize the available information and evidence on both repositioned and experimental drugs for the treatment of COVID-19, focusing on the need to exercise caution on the use of unproven medical therapies.

Immune response in COVID-19: A review

The immune system protects against viruses and diseases and produces antibodies to kill pathogens. This review presents a brief overview of the immune system regarding its protection of the human body from COVID-19; illustrates the process of the immune system, how it works, and its mechanism to fight virus; and presents information on the most recent COVID-19 treatments and experimental data. Various types of potential challenges for the immunes system are also discussed. At the end of the article, foods to consume and avoid are suggested, and physical exercise is encouraged. This article can be used worldwide as a state of the art in this critical moment for promising alternative solutions related to surviving the coronavirus.

Novel Drugs Targeting the SARS-CoV-2/COVID-19 Machinery

Like other human pathogenic viruses, coronavirus SARS-CoV-2 employs sophisticated macromolecular machines for viral host cell entry, genome replication and protein processing. Such machinery encompasses SARS-CoV-2 envelope spike (S) glycoprotein required for host cell entry by binding to the ACE2 receptor, viral RNA-dependent RNA polymerase (RdRp) and 3-chymotrypsin-like main protease (3Clpro/Mpro). Under the pressure of the accelerating COVID-19 pandemic caused by the outbreak of SARS-CoV-2 in Wuhan, China in December 2019, novel and repurposed drugs were recently designed and identified for targeting the SARS-CoV-2 reproduction machinery, with the aim to limit the spread of SARS-CoV-2 and morbidity and mortality due to the COVID-19 pandemic.

Potential Anti-COVID-19 Therapeutics that Block the Early Stage of the Viral Life Cycle: Structures, Mechanisms, and Clinical Trials

The ongoing pandemic of coronavirus disease-2019 (COVID-19) is being caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The disease continues to present significant challenges to the health care systems around the world. This is primarily because of the lack of vaccines to protect against the infection and the lack of highly effective therapeutics to prevent and/or treat the illness. Nevertheless, researchers have swiftly responded to the pandemic by advancing old and new potential therapeutics into clinical trials. In this review, we summarize potential anti-COVID-19 therapeutics that block the early stage of the viral life cycle. The review presents the structures, mechanisms, and reported results of clinical trials of potential therapeutics that have been listed in clinicaltrials.gov. Given the fact that some of these therapeutics are multi-acting molecules, other relevant mechanisms will also be described. The reviewed therapeutics include small molecules and macromolecules of sulfated polysaccharides, polypeptides, and monoclonal antibodies. The potential therapeutics target viral and/or host proteins or processes that facilitate the early stage of the viral infection. Frequent targets are the viral spike protein, the host angiotensin converting enzyme 2, the host transmembrane protease serine 2, and clathrin-mediated endocytosis process. Overall, the review aims at presenting update-to-date details, so as to enhance awareness of potential therapeutics, and thus, to catalyze their appropriate use in combating the pandemic.

Candidate drugs against SARS-CoV-2 and COVID-19

Outbreak and pandemic of coronavirus SARS-CoV-2 in 2019/2020 will challenge global health for the future. Because a vaccine against the virus will not be available in the near future, we herein try to offer a pharmacological strategy to combat the virus. There exists a number of candidate drugs that may inhibit infection with and replication of SARS-CoV-2. Such drugs comprise inhibitors of TMPRSS2 serine protease and inhibitors of angiotensin-converting enzyme 2 (ACE2). Blockade of ACE2, the host cell receptor for the S protein of SARS-CoV-2 and inhibition of TMPRSS2, which is required for S protein priming may prevent cell entry of SARS-CoV-2. Further, chloroquine and hydroxychloroquine, and off-label antiviral drugs, such as the nucleotide analogue remdesivir, HIV protease inhibitors lopinavir and ritonavir, broad-spectrum antiviral drugs arbidol and favipiravir as well as antiviral phytochemicals available to date may limit spread of SARS-CoV-2 and morbidity and mortality of COVID-19 pandemic.

Possible therapeutic agents for COVID-19: a comprehensive review

INTRODUCTION

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has emerged in China. There are no available vaccines or antiviral drugs for COVID-19 patients. Herein, we represented possible therapeutic agents that may stand as a potential therapy against COVID-19.

AREAS COVERED

We searched PubMed, Google Scholar, and clinicaltrials.gov for relevant papers. We showed some agents with potentially favorable efficacy, acceptable safety as well as good pharmacokinetic profiles. Several therapies are under assessment to evaluate their efficacy and safety for COVID-19. However, some drugs were withdrawn due to their side effects after demonstrating some clinical efficacy. Indeed, the most effective therapies could be organ function support, convalescent plasma, anticoagulants, and immune as well as antiviral therapies, especially anti-influenza drugs due to the similarities between respiratory viruses regarding viral entry, uncoating, and replication. We encourage giving more attention to favipiravir, remdesivir, and measles vaccine.

EXPERT OPINION

A combination, at least dual or even triple therapy, of the aforementioned efficacious and safe therapies is greatly recommended for COVID-19. Further, patients should have a routine assessment for their coagulation and bleeding profiles as well as their inflammatory and cytokine concentrations.

Clinical practice of acute pancreatitis in Japan: An analysis of nationwide epidemiological survey in 2016

BACKGROUND

To provide updates on clinical practice of acute pancreatitis (AP) in Japan, we conducted a nationwide epidemiological survey.

METHODS

This study consisted of a two-staged survey; the number of AP patients was estimated by the first-stage survey and their clinical features were examined by the second-stage survey. We surveyed AP patients who had visited hospitals in 2016.

RESULTS

The estimated number of AP patients in 2016 was 78,450, with an overall incidence of 61.8 per 100,000 persons. We obtained detailed clinical information of 2994 AP patients, including 706 (23.6%) severe cases classified according to the Japanese severity criteria. The male-to-female sex ratio was 2.0, and the mean age at onset was 59.9 years in males and 66.5 years in females. Alcohol was the most common etiology (42.8%) in males and gallstones in females (37.7%). The AP-associated mortality was 6.1% in severe AP cases, which was decreased by 40% compared to the 2011 survey. Antibiotics were administered to most cases, with carbapenem being frequently used. Enteral nutrition was given in 31.8% of severe cases, but majority cases received after 48 h. Among the 107 patients who received intervention for walled-off necrosis, five patients received surgery-first approach, 66 received endoscopic ultrasound-guided transluminal drainage, and 19 underwent step-up approach.

CONCLUSIONS

We clarified the current status of AP in Japan including the significant reduction of mortality in severe cases, shift to endoscopic approaches for walled-off necrosis, and poor compliance of the recommendations in the guidelines including management of enteral nutrition and antibiotic administration.

Adipose‑derived mesenchymal stem cells ameliorate dibutyltin dichloride‑induced chronic pancreatitis by inhibiting the PI3K/AKT/mTOR signaling pathway

Adipose-derived mesenchymal stem cells (ASCs) play a positive role in tissue injury repair and regeneration. The aim of this study was to determine whether ASCs could ameliorate chronic pancreatitis (CP) induced by the injection of dibutyltin dichloride (DBTC) and to elucidate its potential mechanisms. Furthermore, this study also explored whether there was a significant difference if the ASCs were injected via the inferior vena cava or the left gastric artery. CP was induced in rats by a single intravenous administration of DBTC, and the accumulation of collagen and apoptotic rates of pancreatic acinar cells were analyzed. According to the results, ASCs markedly reduced DBTC-induced pancreatic damage and collagen deposition in the rat model of CP. Moreover, ASCs significantly decreased pancreatic cell apoptosis by regulating the expression levels of caspase-3, BAX and Bcl-2. These effects were observed regardless of whether the injection was in the inferior vena cava or the left gastric artery. It was also found that the expression levels of phosphorylated PI3K, AKT and mTOR in pancreatic tissues of the DBTC-induced CP model group were significantly increased, while the expression levels of phosphorylated PI3K, AKT and mTOR in the two treatment groups were markedly decreased. ASCs noticeably suppressed the PI3K/AKT/mTOR pathway in the pancreatic tissue of DBTC-induced CP. This study indicated that ASCs protect against pancreatic fibrosis by modulating the PI3K/AKT/mTOR pathway, and have the potential to be a new strategy for the treatment of CP in the future.

Nafamostat mesylate attenuates the pathophysiologic sequelae of neurovascular ischemia

Nafamostat mesylate, an apparent soi-disant panacea of sorts, is widely used to anticoagulate patients undergoing hemodialysis or cardiopulmonary bypass, mitigate the inflammatory response in patients diagnosed with acute pancreatitis, and reverse the coagulopathy of patients experiencing the commonly preterminal disseminated intravascular coagulation in the Far East. The serine protease inhibitor nafamostat mesylate exhibits significant neuroprotective effects in the setting of neurovascular ischemia. Nafamostat mesylate generates neuroprotective effects by attenuating the enzymatic activity of serine proteases, neuroinflammatory signaling cascades, and the endoplasmic reticulum stress responses, downregulating excitotoxic transient receptor membrane channel subfamily 7 cationic currents, modulating the activity of intracellular signal transduction pathways, and supporting neuronal survival (brain-derived neurotrophic factor/TrkB/ERK1/2/CREB, nuclear factor kappa B. The effects collectively reduce neuronal necrosis and apoptosis and prevent ischemia mediated disruption of blood-brain barrier microarchitecture. Investigational clinical applications of these compounds may mitigate ischemic reperfusion injury in patients undergoing cardiac, hepatic, renal, or intestinal transplant, preventing allograft rejection, and treating solid organ malignancies. Neuroprotective effects mediated by nafamostat mesylate support the wise conduct of randomized prospective controlled trials in Western countries to evaluate the clinical utility of this compound.