Antiparasitic Research Articles

The Therapeutic Effect of Shirvan Herbal Ointment on Human Cutaneous Leishmaniasis Compared with Glucantime.

Cutaneous leishmaniasis (CL) infection is caused by the Leishmania major (L. major) parasite and affects 1.5 to 2 million people worldwide each year. Although research into vaccines and antiparasitic drugs has been somewhat successful, their adverse effects include high toxicity, prolonged regeneration, and scarring. This has highlighted the importance of research to replace natural products with antibacterial and antioxidant properties, such as vegetable extracts and oils. Since, the anti-leishmaniasis effect of each of the components of Shirvan herbal ointment (aloe vera, Brazembel, Nigella sativa, propolis, lavender, and olive oil) has been separately studied and confirmed, it seems that the combination of these components can have an increasing anti-leishmanial effect to treat CL. Therefore, this study investigated the therapeutic impact of Shirvan herbal ointment on Iranian patients with leishmaniasis in comparison with glucantime (meglumine). Sixty patients with leishmaniasis were divided into the control and test groups. The control and test groups received intralesional glucantime and Shirvan herbal cream (two times daily), respectively. The size mean of the lesion was 51.5 ± 32.5 before and 11.11 ± 16.28 after treatment in the control group and 50.8 ± 31.2 before and 0.0 ± 0.0 after treatment in the test group. In addition, the period mean of treatment was 43.9 ± 14.4 days and 30.5 ± 7.4 days in the control and test groups, respectively. There was a significant difference in lesion size between the two groups after treatment. Data suggested that Shirvan herbal ointment can be an alternative drug in the treatment of human CL.

A guide for the generation of repositories of clinical samples for research on Chagas disease.

Chagas disease, caused by the parasite Trypanosoma cruzi, affects over 6 million people, mainly in Latin America. Two different clinical phases, acute and chronic, are recognised. Currently, 2 anti-parasitic drugs are available to treat the disease (nifurtimox and benznidazole), but diagnostic methods require of a relatively complex infrastructure and trained personnel, limiting its widespread use in endemic areas, and the access of patients to treatment. New diagnostic methods, such as rapid tests (RDTs) to diagnose chronic Chagas disease, or loop-mediated isothermal amplification (LAMP), to detect acute infections, represent valuable alternatives, but the parasite's remarkable genetic diversity might make its implementation difficult. Furthermore, determining the efficacy of Chagas disease treatment is complicated, given the slow reversion of serological anti-T. cruzi antibody reactivity, which may even take decades to occur. New biomarkers to evaluate early therapeutic efficacy, as well as diagnostic tests able to detect the wide variety of circulating genotypes, are therefore, urgently required. To carry out studies that address these needs, high-quality and traceable samples from T. cruzi-infected individuals with different geographical backgrounds, along with associated clinical and epidemiological data, are necessary. This work describes the framework for the creation of such repositories, following standardised and uniform protocols, and considering the ethical, technical, and logistic aspects of the process. The manual can be adapted according to the resources of each laboratory, to guarantee that samples are obtained in a reproducible way, favouring the exchange of data among different work groups, and their generalizable evaluation and analysis. The main objective of this is to accelerate the development of new diagnostic methods and the identification of biomarkers for Chagas disease.

HYDATID CYST IN CAUDATE LOBE OF LIVER- A THERAPEUTIC CHALLENGE

Background: Treatment of Echinococcal disease depends on the type, size, and location of the cyst, presence of complications, and the experience of the team. Treatment options include percutaneous treatments, surgery, anti-parasitic drugs, and follow-up without intervention. Objectives: To report a case of hydatid cyst located in caudate lobe of liver. Materials and Methods: A 32-year-female, presented with c/o of Pain in abdomen since 1 week localized to right hypochondrium. USG (A+P) was suggestive of hydatid cyst in caudate lobe of liver. MRI was suggestive of hydatid cyst of liver with abutment of left portal vein and IVC. Patient was first started on medical treatment for 6 weeks and then planned for laparoscopic hydatid cyst excision. Cyst was approached laproscopically and fluid aspirated followed by injection of 10% betadine solution (scolicidal) and then reaspirated. Endocyst was removed. The resultant cavity was plugged with omentum. Results: Patient was discharged on POD-3 on T. Albendazole 400 mg BD for 3 months and T. Praziquantal 600 mg once a week for 3 months. After 6 months, patient is symptomatically well and has no complaints or signs of recurrence at present. Conclusion: Minimally invasive laproscopic sugery has more or less replaced the conventional open surgical approach for cystic hydatidosis. Our case is unique due to its location in the caudate lobe of liver alongwith abutment and mild compression of IVC and portal vein which poses a therapeutic challenge to the surgeon. The caudate lobe of the liver is an anatomically complex liver segment. Its unique and intimate location with the hepatic hilum and inferior vena cava (IVC) coupled with its dual supply from both portal pedicles and direct venous drainage into the IVC make vascular control a particular challenge. Technically challenging cyst excision can be performed laparoscopically with its benefits of improved perioperative outcomes.

Insights Into the Evolution, Virulence and Speciation of Babesia MO1 and Babesia divergens Through Multiomics Analyses

Babesiosis, caused by protozoan parasites of the genus Babesia, is an emerging tick-borne disease of significance for both human and animal health. Babesia parasites infect erythrocytes of vertebrate hosts where they develop and multiply rapidly to cause the pathological symptoms associated with the disease. The identification of new Babesia species underscores the ongoing risk of zoonotic pathogens capable of infecting humans, a concern amplified by anthropogenic activities and environmental changes. One such pathogen, Babesia MO1, previously implicated in severe cases of human babesiosis in the United States, was initially considered a subspecies of B. divergens, the predominant agent of human babesiosis in Europe. Here we report comparative multiomics analyses of B. divergens and B. MO1 that offer insight into their biology and evolution. Our analysis shows that despite their highly similar genomic sequences, substantial genetic and genomic divergence occurred throughout their evolution resulting in major differences in gene functions, expression and regulation, replication rates and susceptibility to antiparasitic drugs. Furthermore, both pathogens have evolved distinct classes of multigene families, crucial for their pathogenicity and adaptation to specific mammalian hosts. Leveraging genomic information for B. MO1, B. divergens, and other members of the Babesiidae family within Apicomplexa provides valuable insights into the evolution, diversity, and virulence of these parasites. This knowledge serves as a critical tool in preemptively addressing the emergence and rapid transmission of more virulent strains.

Anti-cancer effects of nitazoxanide in epithelial ovarian cancer in-vitro and in-vivo

Epithelial ovarian cancer is one of the most lethal gynecologic malignancies and poses a considerable threat to women's health. Although the progression-free survival of patients has been prolonged with the application of anti-angiogenesis drugs and Poly (ADP-ribose) polymerases (PARP) inhibitors, overall survival has not substantially improved. Thus, new therapeutic strategies are essential for the treatment of ovarian cancer. Nitazoxanide (NTZ), an FDA-approved anti-parasitic drug, has garnered attention for its potential anti-cancer activity. However, the anti-tumor effects and possible underlying mechanisms of NTZ on ovarian cancer remain unclear. In this study, we investigated the anti-tumor effects and the mechanism of NTZ on ovarian cancer in vitro and in vivo. We found that NTZ inhibited the proliferation of A2780 and SKOV3 epithelial ovarian cancer cells in a time- and concentration-dependent manner; Furthermore, NTZ suppressed the metastasis and invasion of A2780 and SKOV3 cells in vitro, correlating with the inhibition of epithelial-mesenchymal transition; Additionally, NTZ suppressed the Hippo/YAP/TAZ signaling pathway both in vitro and in vivo and demonstrated a good binding activity with core genes of Hippo pathway, including Hippo, YAP, TAZ, LATS1, and LATS2. Oral administration of NTZ inhibited tumor growth in xenograft ovarian cancer mice models without causing considerable damage to major organs. Overall, these data suggest that NTZ has therapeutic potential for treating epithelial ovarian cancer.

Diagnostic dilemma: axillary cysticercosis masquerading as breast mass

Cysticercosis, caused by the tapeworm Taenia solium, is a significant public health concern, particularly prevalent in developing nations. We present a case of isolated cysticercosis in the axillary region, mimicking a breast mass, in a 47-year-old woman who presented with a gradually enlarging mass in her right axilla and was initially diagnosed with fibroadenoma. However, further investigations revealed cysticercosis in the larvae, including ultrasonography and fine-needle aspiration cytology (FNAC). The patient underwent surgical excision of the cysts following a two-week course of albendazole therapy. Histopathological examination confirmed cysticercosis with a foreign body giant cell reaction. Cysticercosis typically involves muscular and subcutaneous tissues, posing diagnostic challenges due to its resemblance to other conditions. Ultrasonography, FNAC, and MRI play crucial roles in accurate diagnosis. Treatment involves a combination of surgical removal and antiparasitic medications such as albendazole. This case highlights the importance of considering cysticercosis in differential diagnosis, especially in endemic regions, and underscores the effectiveness of a comprehensive treatment approach integrating medical therapy and surgical intervention. Effective management ensures the eradication of parasitic infection and the alleviation of associated symptoms, exemplifying patient-cantered care for optimal outcomes. Increased awareness, preventive measures, and early diagnosis are essential for mitigating the burden of cysticercosis, particularly in regions with poor sanitation and high prevalence rates.

Improving the Solubility, Stability, and Bioavailability of Albendazole through Synthetic Salts.

Albendazole (ABZ) is a highly effective yet poorly water-soluble antiparasitic drug known to form salts (ABZ-FMA, ABZ-DTA, and ABZ-HCl) with fumaric acid (FMA), D-tartaric acid (DTA), and hydrochloric acid (HCl). This research utilized a range of analytical techniques, including Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance hydrogen spectroscopy (1H NMR), powder X-ray diffraction (PXRD), dynamic vapor sorption (DVS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM), to validate and characterize the solid-state properties of these drug salts. This study also assessed the solubility and intrinsic dissolution rate (IDR) of these salts under different pH conditions compared to the active pharmaceutical ingredient (API) and conducted stability studies. Moreover, the in vivo pharmacokinetic performance of ABZ salt was evaluated. The results of this study reveal that the new solid form of ABZ is primarily associated with amino acid esters and benzimidazole groups, forming intermolecular interactions. All three ABZ salts significantly improved the solubility and dissolution rate of ABZ, with ABZ-HCl demonstrating the optimal performance. Importantly, the drug salt exhibited robust physical stability when exposed to adverse conditions, including strong light irradiation (4500 ± 500 lux), high humidity (92.5 ± 5% relative humidity), elevated temperatures (50 ± 2 °C), and accelerated test conditions (40 °C/75 ± 5% relative humidity). Lastly, the in vivo pharmacokinetic analysis demonstrated that ABZ salt led to a substantial increase in AUC(0-24) and Cmax compared to ABZ. This elevation in solubility in aqueous solvents signifies that ABZ salt exhibits characteristics that can enhance oral bioavailability and pharmacokinetics. These findings provide potential solutions for the development of more effective and innovative drug formulations.

Follow up study of symptomatic human cystic echinococcosis treatment with albendazole and praziquantel, in Uruguay

BackgroundCystic echinococcosis (CE) is a chronic disease considered a neglected one. Cystic echinococcosis is endemic in Uruguay and the region. Surgery, using various technical approaches, has the potential to safely remove the cyst(s) and lead to a complete cure in a high number of patients with simple forms of CE. However, surgery may be impractical in patients with multiple cysts in several organs, high surgical risk, or in patients with previous multiple surgeries. In these cases, the pharmacological treatment with the benzimidazolic drug Albendazole (ABZ) alone or combined with Praziquantel (PZQ), has been promising as the best choice to achieve improvement or cure.MethodsIn this study, we analyze the results obtained on the anti-parasitic treatment of 43 patients diagnosed with CE between the years 2003 and 2020. Patients were treated before and/or after surgery with ABZ or the combination ABZ/PZQ. The standardize protocol of the anti-parasitic drug treatment before surgery was 7 days, 15 days or 1 month depending on the urgency and availability of the surgical procedure. All cases that involved confirmed locations on lungs underwent immediate surgery with minimal pre-treatment when possible. After surgery, the standardize protocol of anti-parasitic drug treatment consisted of six cycles of 30 days each and resting intervals of 15 days in between. ABZ was used in all cases, administered orally, twice daily, at a total dosage of 15 mg/kg/day, with food high in fat content for improved absorption. The follow up was carried out according to WHO-IWGE guidelines for 5 years.ResultsOf the 43 patients fourteen were ≤ 15 years of age and had a differentiated pre-surgical treatment. From the ≥ 16 years of age, 36 completed the treatments and the 5 years follow up. Four patients changed geographical locations, without a forwarding contact, after the post-surgery treatment. No patient died during the study. Of the 36 patients that completed the study, 32 were treated only with ABZ; 93.75% achieved treatment success as determined by improvement or cure, and 6.25% treatment failure determined by no change or worsening. The last four patients received the ABZ/PZQ combination therapy and achieved 100% treatment success.ConclusionThe pharmacological treatment resulted in a good option not only as palliative but also as potentially curative. The main relevance of its use was in cases with previous multiple surgeries or surgeries with potential life-threatening complications due to the number and location of cysts and concurrent comorbidities. A follow-up of at least 5 years would be recommended to assure remission and control of the transmission. More randomized trials are needed to provide clear clinical evidence of different pharmacological treatments for CE.

Green Synthesis of Chitosan/Silver Nanoparticles Using Citrus paradisi Extract and Its Potential Anti-Cryptosporidiosis Effect.

Cryptosporidium parvum (C. parvum) is one of the most prevalent species infecting humans and animals. Currently, the only FDA-licensed drug to treat cryptosporidiosis is nitazoxanide (NTZ), with no efficacy in immunocompromised hosts. Citrus paradisi (C. paradisi) has demonstrated anti-protozoal activities. This study aimed to investigate the anti-cryptosporidiosis effect of C. paradisi peel extract, either alone or in mediating the green synthesis of chitosan silver nanoparticles (Cs/Ag NPs), compared to NTZ. Mice were sorted into nine different groups. The effectiveness of the treatments was evaluated using parasitology, histopathology, immunohistochemistry, and immunology. C. paradisi outperformed nitazoxanide regarding oocyst shedding (79% vs. 61%). The effectiveness of NTZ Cs/Ag NPs and Citrus Cs/Ag NPs was enhanced to 78% and 91%, respectively. The highest oocyst inhibition was obtained by combining NTZ and Citrus Cs/Ag NPs (96%). NF-κB, TNF-α, and Il-10 levels increased in response to infection and decreased in response to various treatments, with the highest reduction in the group treated with combined NTZ citrus Cs/Ag NPs. Combining C. paradisi with NTZ could have a synergistic effect, making it a potentially effective anti-cryptosporidiosis agent. Utilizing C. paradisi in the green synthesis of Cs/Ag NPs improves the therapeutic response and can be used to produce novel therapeutic antiparasitic drugs.

Cerebral Endoscopy in Hydrocephalus Secondary to Neurocysticercosis

Neurocysticercosis (NCC) is a common parasite affecting the central nervous system, causing over 50,000 fatalities annually in Latin America. Treatment varies depending on the location and prognosis is not good. Treatment often involves anti-parasitic medications and shunt implantation. Meningitis, stroke, and hydrocephalus are common complications. Endoscopy is the primary treatment for ventricular forms, but alternative methods like shunt implantation and microsurgery are considered. Anti-cysticercus medications and shunt implantation are recommended for patients with subarachnoid forms and hydrocephalus. Endoscopy is a potential treatment for extra-parenchymal NCC due to its potential to reduce inflammation and improve cerebrospinal fluid (CSF) circulation. However, early extraction may reduce the risk of chronic inflammation. Patients without extracorporeal membranes (ETV) have a higher shunt failure rate, potentially due to tolerance to changes in CSF flow. The Karnofsky index, an estimate used to evaluate functional status, suggests that endoscopy as an initial therapy is a viable option. Patients with a history of shunting or chronic illness may benefit from a comprehensive examination of the ventricular system and basal subarachnoid space. Steroid administration is recommended after treatment to prevent parasitic antigen release and immune response.

A Retrospective Longitudinal Study of Refugees With Eosinophilia at an Academic Center in the United States From 2015 to 2020.

Refugees to the United States frequently have parasitic infections. If untreated, parasites can cause severe complications. The purpose of this study was to investigate the incidence, management, and outcomes of eosinophilia as a biomarker for parasites. We conducted a retrospective longitudinal chart review of consecutive refugees attending 3 refugee clinics in Rhode Island that manage the health care of all pediatric and adult refugees. Among 812 refugees who met inclusion criteria, 147 (18.1%) had eosinophilia upon arrival and almost half had ≥1 symptom. The rates and severity of eosinophilia in those with predeparture presumptive treatment records who did (112/115, 97.4%) or did not (488/498, 98.0%) receive predeparture antiparasitic treatment were similar. All refugees with eosinophilia had ≥1 parasitic test in the United States. The most common attributable parasites were Schistosoma and Strongyloides stercoralis. Overall, parasites were detected in 63 (42.9%) of 147 refugees with eosinophilia by either stool testing, serology, or blood smear, but testing was inconsistent and likely underestimated true incidence. Only some of the identified parasites typically cause eosinophilia. Forty-five (30.6%) refugees with eosinophilia received antiparasitics in the United States. Of 81 (55.1%) individuals who had repeat blood tests, eosinophilia had resolved in 52 (64.2%). Five individuals (3.4%) had alternative diagnoses, including eczema, myelofibrosis, and drug allergy. Our findings support Centers for Disease Control and Prevention recommendations to screen for eosinophilia in newly arrived refugees. Follow-up after 3-6 months is critical to confirm resolution of residual eosinophilia, which frequently occurs after effective predeparture treatment or if eosinophilia persists, to diagnose active parasitic infections.

A recombinant Getah Virus expressing a GFP gene for rapid neutralization testing and antiviral drug screening assay

Getah virus (GETV) is a re-emerging mosquito-borne RNA virus that induces fever, hind limb edema, swollen submandibular lymph nodes, and urticaria in horses. In pigs, the virus often results in stillbirths among pregnant sows, and neurological symptoms leading to death in piglets. Currently, there are no specific treatments or drugs available for GETV infection. The use of reporter viruses to monitor viral replication and spread in real-time within infected cells and animals provides a powerful tool for targeting antiviral drugs throughout the viral life cycle. Their fluorescence-tracked characteristics greatly facilitate virus neutralization tests (VNTs). In this study, we engineered two recombinant viruses by inserting different reporter protein genes at the 3′ end of the structural protein gene, an unreported location that can accommodate exogenous genes. The rGEEiLOV and rGEEGFP viruses demonstrated genetic stability for at least five passages and replicated at a rate similar to that of the parental virus in BHK-21 cells. The rGEEGFP virus facilitated viral neutralization testing. Additionally, we used the reporter virus rGEEGFP to confirm ivermectin, a broad-spectrum antiparasitic agent, as a potential inhibitor of GETV in vitro. Ivermectin appears to inhibit the early replication stages of the virus and can block cell-to-cell viral transmission. In conclusion, rGEEGFP holds significant potential for antiviral screening to identify specific inhibitors against GETV and for use in viral neutralization tests.

Doramectin attenuates inflammation, obesity and insulin resistance in food-borne obese mice

The avermectin derivative doramectin is widely used clinically as an antiparasitic drug and, in addition, doramectin may have a modulatory role in obesity. Adipose tissue macrophage recruitment and polarization play an important role in obesity-induced inflammation and insulin resistance. The aim of this study was to investigate the effects of doramectin on high-fat diet-induced inflammation and macrophage polarization in white adipose tissue of epididymis of obese mice. We found that compared with high-fat diet-fed obese mice, doramectin treatment resulted in a significant decrease in body weight and lipid levels, improved insulin resistance, an increase in the proportion of M2-type macrophages and a decrease in the proportion of M1-type macrophages in the epididymal white adipose tissues, as well as a decrease in the infiltration of inflammatory cells in the adipose tissues. Thus, doramectin can ameliorate high-fat diet-induced obesity and adipose inflammation by affecting macrophage polarization in white adipose tissue.

Peculiar Presentation: Dirofilariasis Unveiled in the Temporalis Muscle of a Teenager.

Dirofilariasis, a parasitic infection typically affecting animals, occasionally presents in humans, transmitted through mosquito bites. This article explores an unusual case of dirofilariasis affecting the temporalis muscle, a rare occurrence. With 40 identified Dirofilaria species, human infections are primarily attributed to Dirofilaria repens and Dirofilaria immitis, causing pulmonary and subcutaneous lesions. While deep tissue infections are exceptionally rare, we present a unique case in a 15-year-old girl. The patient exhibited a 3-month history of a slowly growing swelling in the left temporal region, accompanied by intermittent pain and limited jaw movement. Initial differential diagnoses included benign tumors, cysts, or abscesses. Ultrasound revealed a hypoechoic mass, leading to surgical excisional biopsy. Histopathological examination confirmed Dirofilaria, prompting a combination of antiparasitic medication and surgical intervention. Dirofilariasis in deep tissues, especially muscles, is uncommon. Diagnosis challenges arise due to its rarity and similarity to other conditions. Imaging may not be specific, necessitating histopathological examination. Treatment involves antiparasitic medications like ivermectin, supplemented with surgery in specific cases. Our patient's favorable outcome underscores the importance of early recognition and a multidisciplinary approach for effective management.

Molecular Models of Toxoplasma gondii in Humans and Animals.

Toxoplasma gondii (T. gondii) is an obligate intracellular, zoonotic protozoan parasite of interest to physicians and veterinarians with its highly complex structure. It is known to infect about one-third of the world's population. Since it is a zoonotic disease, it is necessary to keep the animal population under control in order to prevent human exposure. Many studies have been conducted on the detection of T. gondii and it has been determined that there are three clonal groups consisting of types 1, 2, 3. Developments in molecular studies have led to changes in the taxonomy and new developments in parasitic diseases. It has helped in diagnosis, treatment, development of antiparasitic drugs and research on resistance. They also provided research on vaccine studies, genetic typing and phylogenetics of parasitic diseases. Conventional polymerase chain reaction (PCR), real-time PCR and genotyping studies conducted today increase our knowledge about T. gondii. Methods such as B1, SAG1, SAG2, GRA1, 529-bp repeat element, OWP genes and 18S rRNAs are mostly used in PCR, and methods such as MS, MLST, PCR-RFLP, RAPD-PCR and HRM are used in genotyping. Toxoplasmosis is a disease that is within the framework of the concept of one health and must attract attention, has not yet been eradicated in the world and needs joint studies for humans, animals and ecosystems to be eradicated. This can only be possible by establishing interdisciplinary groups, conducting surveys and training.

Identification of Innovative Folate Inhibitors Leveraging the Amino Dihydrotriazine Motif from Cycloguanil for Their Potential as Anti-Trypanosoma brucei Agents.

Folate enzymes, namely, dihydrofolate reductase (DHFR) and pteridine reductase (PTR1) are acknowledged targets for the development of antiparasitic agents against Trypanosomiasis and Leishmaniasis. Based on the amino dihydrotriazine motif of the drug Cycloguanil (Cyc), a known inhibitor of both folate enzymes, we have identified two novel series of inhibitors, the 2-amino triazino benzimidazoles (1) and 2-guanidino benzimidazoles (2), as their open ring analogues. Enzymatic screening was carried out against PTR1, DHFR, and thymidylate synthase (TS). The crystal structures of TbDHFR and TbPTR1 in complex with selected compounds experienced in both cases a substrate-like binding mode and allowed the rationalization of the main chemical features supporting the inhibitor ability to target folate enzymes. Biological evaluation of both series was performed against T. brucei and L. infantum and the toxicity against THP-1 human macrophages. Notably, the 5,6-dimethyl-2-guanidinobenzimidazole 2g resulted to be the most potent (Ki = 9 nM) and highly selective TbDHFR inhibitor, 6000-fold over TbPTR1 and 394-fold over hDHFR. The 5,6-dimethyl tricyclic analogue 1g, despite showing a lower potency and selectivity profile than 2g, shared a comparable antiparasitic activity against T. brucei in the low micromolar domain. The dichloro-substituted 2-guanidino benzimidazoles 2c and 2d revealed their potent and broad-spectrum antitrypanosomatid activity affecting the growth of T. brucei and L. infantum parasites. Therefore, both chemotypes could represent promising templates that could be valorized for further drug development.

Potential Drugs in COVID-19 Management.

The SARS-CoV-2 virus first emerged in China in December 2019 and quickly spread worldwide. Despite the absence of a vaccination or authorized drug specifically developed to combat this infection, certain medications recommended for other diseases have shown potential effectiveness in treating COVID-19, although without definitive confirmation. This review aims to evaluate the existing literature on the efficacy of these medications against COVID-19. The review encompasses various potential treatments, including antiviral medications, anti-malaria and anti-rheumatic drugs, vaccines, corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs), antipyretic and analgesic medicines, antiparasitic drugs, and statins. The analysis also addresses the potential benefits and drawbacks of these medications, as well as their effects on hypertension and diabetes. Although these therapies hold promise against COVID-19, further research, including suitable product production or clinical testing, is needed to establish their therapeutic efficacy.

DNA G-quadruplexes in the genome of Trypanosoma cruzi as potential therapeutic targets for Chagas disease: Dithienylethene ligands as effective antiparasitic agents

Chagas disease is caused by the parasite Trypanosoma cruzi and affects over 7 million people worldwide. The two actual treatments, Benznidazole (Bzn) and Nifurtimox, cause serious side effects due to their high toxicity leading to treatment abandonment by the patients. In this work, we propose DNA G-quadruplexes (G4) as potential therapeutic targets for this infectious disease. We have found 174 PQS per 100,000 nucleotides in the genome of T. cruzi and confirmed G4 formation of three frequent motifs. We synthesized a family of 14 quadruplex ligands based in the dithienylethene (DTE) scaffold and demonstrated their binding to these identified G4 sequences. Several DTE derivatives exhibited micromolar activity against epimastigotes of four different strains of T. cruzi, in the same concentration range as Bzn. Compounds L3 and L4 presented remarkable activity against trypomastigotes, the active form in blood, of T. cruzi SOL strain (IC50 = 1.5–3.3 μM, SI = 25–40.9), being around 40 times more active than Bzn and displaying much better selectivity indexes.

Overcoming flumatinib resistance in chronic myeloid leukaemia: Insights into cellular mechanisms and ivermectin's therapeutic potential.

Chronic myeloid leukaemia (CML) is a haematological malignancy characterized by the constitutive tyrosine kinase activity of the BCR-ABL1 fusion protein. Flumatinib, a second-generation tyrosine kinase inhibitor, has exhibited superior clinical efficacy compared to its precursor, imatinib. However, with increased clinical use, resistance to flumatinib has emerged as a significant challenge. To investigate the mechanisms of flumatinib resistance in CML, we induced the human CML cell line K562 using a flumatinib concentration gradient method invitro, successfully establishing a flumatinib-resistant K562/FLM cell line. This cell line exhibited cross-resistance to imatinib and doxorubicin, but remained sensitive to the antiparasitic agent ivermectin, which possesses antitumoural effects. Through cellular experimentation, we explored the resistance mechanisms, which indicated that K562/FLM cells evade flumatinib cytotoxicity by enhancing autophagy, increasing the expression of membrane transport proteins, particularly P-glycoprotein, ABCC1 and ABCC4, as well as enhancing phosphorylation of p-EGFR, p-ERK and p-STAT3 proteins. Moreover, it was found that ivermectin effectively suppressed the expression of autophagy and transport proteins in K562/FLM cells, reduced the activity of the aforementioned phosphoproteins, and promoted apoptotic cell death. Collectively, the increased autophagy, higher expression of drug-efflux proteins and hyperactivation of the EGFR/ERK/STAT3 signalling pathway were identified as pivotal elements promoting resistance to flumatinib. The significant effects of ivermectin might offer a novel therapeutic strategy to overcome flumatinib resistance and optimize the treatment outcomes of CML.

Potential of Streptomyces avermitilis: A Review on Avermectin Production and Its Biocidal Effect.

Secondary metabolites produced by the fermentation of Streptomyces avermitilis bacterium are powerful antiparasitic agents used in animal health, agriculture and human infection treatments. Avermectin is a macrocyclic lactone with four structural components (A1, A2, B1, B2), each of them containing a major and a minor subcomponent, out of which avermectin B1a is the most effective parasitic control compound. Avermectin B1a produces two homologue avermectins (B1 and B2) that have been used in agriculture as pesticides and antiparasitic agents, since 1985. It has a great affinity with the Cl-channels of the glutamate receptor, allowing the constant flow of Cl- ions into the nerve cells, causing a phenomenon of hyperpolarization causing death by flaccid paralysis. The purpose of this work was to gather information on the production of avermectins and their biocidal effects, with special emphasis on their role in the control of pests and phytopathogenic diseases. The literature showed that S. avermitilis is an important producer of macrocyclic lactones with biocidal properties. In addition, avermectin contributes to the control of ectoparasites and endoparasites in human health care, veterinary medicine and agriculture. Importantly, avermectin is a compound that is harmless to the host (no side effects), non-target organisms and the environment.