Efficacy of pentamidine-loaded chitosan nanoparticles as a novel drug delivery system for Leishmania tropica

@#The present study compares the in vitro effects of nanoparticles loaded pentamidine drug and conventional pentamidine on Leishmania tropica. Herein, pentamidine-loaded chitosan nanoparticles (PTN-CNPs) have been synthesized through an ionic gelation method with sodium tripolyphosphate (TPP). Next, the physical characteristics of PTN-CNPs were determined through the surface texture, zeta potential, in vitro drug release, drug loading content (DLC), and encapsulation efficacy (EE) and compared its efficacy with free pentamidine (PTN) drug against promastigotes and axenic amastigotes forms of L. tropica in vitro. The PTN-CNPs displayed a spherical shape having a size of 88 nm, an almost negative surface charge (-3.09 mV), EE for PTN entrapment of 86%, and in vitro drug release of 92% after 36 h. In vitro antileishmanial activity of PTN-CNPs and free PTN was performed against Leishmania tropica KWH23 promastigote and axenic amastigote using 3-(4, 5- dimethylthiazol-2-yl)-2, 5-diphenyletetrazolium bromide (MTT) assay. It was observed that the effect of PTN-CNPs and free PTN on both forms of the parasite was dose and time dependent. Free PTN presented low efficacy even at higher dose (40 µg/ml) with 25.6 ± 1.3 and 26.5 ±1.4 mean viability rate of the promastigotes and axenic amastigotes, respectively after 72 hrs incubation. While PTN-CNPs showed strong antileishmanial effects on both forms of parasite with 16 ± 0.4 and 19 ± 0.7 mean viability rate at the same higher concentration (40 µg/ml) after 72 hrs incubation. Half maximal inhibitory concentration (IC50) values of PTN-CNPs toward promastigotes and amastigotes were obtained as 0.1375 µg/ml and 0.1910 µg/ml, respectively. In conclusion, PTN-CNPs effectively inhibited both forms of the L. tropica; however, its effect was more salient on promastigotes. This data indicates that the PTN-CNPs act as a target drug delivery system. However, further research is needed to support its efficacy in animal and human CL.

Treatment of tegumentary leishmaniasis in two hemodialysis patients with end-stage renal disease using two series of pentamidine

Abstract In this study, we present two cases of cutaneous leishmaniasis in patients with end-stage renal disease, who were treated solely with intramuscular pentamidine. In such cases, treatment implies a fine line between therapeutic efficacy and toxicity. This is suggestive of a knowledge gap; however, findings indicate that this is still the fastest and safest alternative to the treatment with antimonials. Also, it can help avoid the side effects that occur upon using antimonials.

Pentamidine Inhibits Titanium Particle-Induced Osteolysis In Vivo and Receptor Activator of Nuclear Factor-κB Ligand-Mediated Osteoclast Differentiation In Vitro

BACKGROUND: Wear debris-induced osteolysis leads to periprosthetic loosening and subsequent prosthetic failure. Since excessive osteoclast formation is closely implicated in periprosthetic osteolysis, identification of agents to suppress osteoclast formation and/or function is crucial for the treatment and prevention of wear particle-induced bone destruction. In this study, we examined the potential effect of pentamidine treatment on titanium (Ti) particle-induced osteolysis, and receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis. METHODS: The effect of pentamidine treatment on bone destruction was examined in Ti particle-induced osteolysis mouse model. Ti particles were implanted onto mouse calvaria, and vehicle or pentamidine was administered for 10 days. Then, calvarial bone tissue was analyzed using micro-computed tomography and histology. We performed in vitro osteoclastogenesis assay using bone marrow-derived macrophages (BMMs) to determine the effect of pentamidine on osteoclast formation. BMMs were treated with 20 ng/mL RANKL and 10 ng/mL macrophage colony-stimulating factor in the presence or absence of pentamidine. Osteoclast differentiation was determined by tartrate-resistant acid phosphatase staining, real-time polymerase chain reaction, and immunofluorescence staining. RESULTS: Pentamidine administration decreased Ti particle-induced osteoclast formation significantly and prevented bone destruction compared to the Ti particle group in vivo. Pentamidine also suppressed RANKL-induced osteoclast differentiation and actin ring formation markedly, and inhibited the expression of nuclear factor of activated T cell c1 and osteoclast-specific genes in vitro. Additionally, pentamidine also attenuated RANKL-mediated phosphorylation of IκBα in BMMs. CONCLUSION: These results indicate that pentamidine is effective in inhibiting osteoclast formation and significantly attenuates wear debris-induced bone loss in mice.

Good response to pentamidine isethionate in a case of Mucosal Leishmaniasis caused by Leishmania (Viannia) braziliensis that was difficult to treat: Case Report

Abstract In Brazil, meglumine antimoniate is the first drug of choice for mucosal leishmaniasis treatment followed by amphotericin B and pentamidine isethionate. We report the case of a patient with severe mucosal lesions caused by Leishmania (Viannia) braziliensis that were difficult to treat. Over a 14-year period, the patient showed low adherence and three treatment attempts with meglumine antimoniate failed. Additionally, there was an unsatisfactory response to liposomal amphotericin B and nephrotoxicity when using amphotericin B deoxycholate that persisted after new treatment attempt with liposomal amphotericin B. Finally, healing was achieved with pentamidine isethionate and maintained during nine months of monitoring.

Therapeutic response and safety of the topical, sequential use of antiseptic, keratolytic, and pentamidine creams (3-PACK) on Leishmania (Viannia) braziliensis-infected mice

BACKGROUND Topical treatment of New World cutaneous leishmaniasis can be affected by bacterial coinfection, hyperkeratosis, and transdermal drug delivery. OBJECTIVE The aim of this work was to evaluate the therapeutic response and safety of the topical, sequential use of antiseptic, keratolytic, and pentamidine isethionate (PMD) creams (3-PACK kit) on CL-infected BALB/c mice. METHODS A 0.5% chlorhexidine solution (CGH), 10% salicylic acid (SA), and 3% or 6% PMD were used as antiseptic, keratolytic, and antileishmanial drugs, respectively. During the first seven days, antiseptic, followed by 10% SA gel and PMD cream, were applied topically. Subsequently, treatment was performed only with the antiseptic and PMD creams. Skin irritation, reduction of lesion size (mm2), and parasitic load were observed until 30 days of treatment were completed. FINDINGS The 3-PACK treatment using 6% PMD induced a complete lesion reduction in 3/6 mice and a partial reduction in 1/6 mice, with no parasites observed. In contrast, CGH and SA alone, along with the vehicle, were not effective (p < 0.05). Moderate to severe erythema was observed at the application site. MAIN CONCLUSION The topical 3-PACK using 6% PMD was 67% effective in the treatment of CL by Leishmania (Viannia) braziliensis. Currently, work is ongoing to improve PMD isethionate formulation and to determine a dose-response.

Efficacy and safety of a single dose pentamidine (7mg/kg) for patients with cutaneous leishmaniasis caused by L. guyanensis: a pilot study

Abstract: BACKGROUND: There have been few studies on pentamidine in the Americas; and there is no consensus regarding the dose that should be applied. OBJECTIVES: To evaluate the use of pentamidine in a single dose to treat cutaneous leishmaniasis. METHODS: Clinical trial of phase II pilot study with 20 patients. Pentamidine was used at a dose of 7 mg/kg, in a single dose. Safety and adverse effects were also assessed. Patients were reviewed one, two, and six months after the end of treatments. RESULTS: there was no difference between the treatment groups in relation to gender, age, number or location of the lesions. Pentamidine, applied in a single dose, obtained an effectiveness of 55%. Mild adverse events were reported by 17 (85%) patients, mainly transient pain at the site of applications (85%), while nausea (5%), malaise (5%) and dizziness (5%) were reported in one patient. No patient had sterile abscess after taking medication at a single dose of 7mg/kg. CONCLUSIONS: Clinical studies with larger samples of patients would enable a better clinical response of pent amidine at a single dose of 7mg, allowing the application of more powerful statistical tests, thus providing more evidences of the decrease in the effectiveness of that medication. Hence, it is important to have larger studies with new diagrams and/or new medications.

American tegumentary leishmaniasis - a case of therapeutic challenge

American Tegumentary Leishmaniasis (ATL) is a chronic, non-contagious, infectious disease affecting millions of people worldwide. The timely and proper treatment is of great importance to prevent the disease from progressing to destructive and severe forms. Treatment for ATL recommended by the Brazilian Ministry of Health is similar for the whole country, regardless of the species of Leishmania. It is known that the response to treatment may vary with the strain of the parasite, the immune status of the patient and clinical form. We report the case of a healthy patient, coming from Manaus, Amazonas state, Brazil, who presented resistance to treatment with N-methyl-glutamine and liposomal amphotericin B, only being healed after using pentamidine.

Estudo comparativo entre o antimoniato-n-metilglucamina (glucantime) e o isotionato de pentamidina (pentacarinat) em lesões cutâneas da leishmaniose tegumentar / Comparative study of antimony-n-methylglucamine (glucantime) and pentamidine isethionate (Pentacarinat) in skin lesions of cutaneous leishmaniasis

O prognóstico da leishmaniose cutânea (LC) com o uso dos antimoniais pentavalentes (Sb+5) de um modo geral é considerado bom, embora alguns casos tornem-se refratários à terapêutica tradicional. Infelizmente, não existem marcadores de gravidade da doença ou marcadores de resposta terapêutica, limitando a utilização de formas de tratamento mais efetivas. Em alguns casos, porém, existe a necessidade de utilizar outras drogas, como a anfotericina B (desoxocolato) e as pentamidinas (isotionato e mesilato), consideradas como drogas de 2ª escolha no tratamento das leishmanioses, sendo de fundamental importância à busca de novos esquemas terapêuticos. O objetivo do estudo foi comparar a eficácia entre o antimoniato-N-metilglucamina (Glucantime®) e o isotionato de pentamidina (Pentacarinat®) no tratamento da forma cutânea da leishmaniose tegumentar (LT)...

The prognosis of cutaneous leishmaniasis (CL) with the use of pentavalents antimonials (Sb+5) is generally considered good, although in some cases have become refractory to conventional therapy. Unfortunately there are no markers of disease severity or markers of therapeutic response, limiting the use of more effective forms of treatment. In some cases, however, there is a need for other drugs such as amphotericin B (desoxycholate) and pentamidine (isethionate and mesylate), which are considered as the second choice in the treatment of leishmaniasis, since few studies with reduced doses of these drugs demonstrated encouraging results in tegumentary leishmaniasis (TL), which is paramount in the search for new therapeutic regimens using proven antileishmanial drugs. We have compared the effectiveness between the N-methylglucamine antimoniate (Glucantime®) and pentamidine isethionate (Pentacarinat®) in the treatment of CL in an endemic area of tegumentary leishmaniasis (TL)...

Profilaxis de neumonía por Pneumocystis jiroveci en niños y adultos sometidos a trasplante de órganos sólidos y de precursores hematopoyéticos / Prophylaxis against Pneumocystis pneumonia in pediatric and adult patients undergoing solid organ or hematopoietic stem cells transplantation

Pneumocystis jiroveci is an important pathogen in patients undergoing SOT and HSCT. Universal prophylaxis is recommended for all adults and children with SOT and HSCT, considering that its use significantly reduces the occurrence and mortality associated with pneumonia by this agent. The drug of choice is cotrimoxazole (A1) three times a week, low-dose scheme, that has proved equally effective and better tolerated than the daily regimen and/or at high doses. Prophylaxis starts 7 to 14 days post transplant in SOT recipients and post-implant in HSCT, with an average duration of 6 months except in liver and lung transplant as in HSCT with significant degree of immunosuppression, that lasts for 1 year. Alternatives for prophylaxis are dapsone (B2), aerosolized pentamidine (B2) and atovaquone (C2).

Pneumocystis jiroveci es un patógeno importante en pacientes sometidos a TOS y TPH. Se recomienda proilaxis universal a todos los pacientes adultos y niños sometidos a TOS o TPH porque su uso reduce signiicati-vamente la ocurrencia y mortalidad asociada a neumonía por este agente. El medicamento de elección es cotrimoxa-zol (A1) tres veces por semana, en dosis bajas, esquema que ha demostrado igual eicacia y mejor tolerancia que el esquema diario y/o con dosis altas. La proilaxis se inicia 7 a 14 días post trasplante en TOS y posterior al implante en TPH, con una duración promedio de 6 meses salvo en trasplante de hígado y pulmón en que se prolonga por 1 año, al igual que en TPH con grado importante de inmunosupresión. Son alternativas de profilaxis dapsona (B2), pentamidina aerosolizada (B2) y atavacuona (C2).

Hypoglycemic Seizures Associated with Pentamidine for Pneumocystis jiroveci Pneumonia in a HIV Patient / 대한내과학회지

Trimethoprim-sulfamethoxazole (TMX-SMZ) is the initial treatment for Pneumocystis jiroveci pneumonia in human immunodeficiency virus (HIV) patients. About 20% of patients do not complete the TMX-SMZ treatment due to treatment failure or adverse reactions. Pentamidine isethionate has been used for P. jiroveci pneumonia as a second-line regimen. Although hypoglycemia is a common adverse effect of pentamidine, pentamidine-induced hypoglycemia has not been reported in Korea. We present an HIV patient with grand mal seizures caused by pentamidine-induced hypoglycemia who was managed successfully with IV dextrose infusion. Mental changes can occur during pentamidine treatment, but hypoglycemia is often ignored and misdiagnosed as epilepsy or stroke. It can result in seizures, coma, and even death. We should be aware of pentamidine-induced hypoglycemia, which can lead to severe neurologic deficits and diabetes mellitus.

Estudo clínico randomizado comparando antimoniato de meglumina, pentamidina e anfotericina B para o tratamento da leishmaniose cutânea ocasionada por Leishmania guyanensis / A randomized clinical trial comparing meglumine antimoniate, pentamidine and amphotericin B for the treatment of cutaneous leishmaniasis by Leishmania guyanensis

FUNDAMENTOS: O tratamento da leishmaniose tegumentar americana (LTA) ainda constitui desafio, pois a maioria dos medicamentos é injetável e têm-se poucos ensaios clínicos randomizados comparando a eficácia das drogas. Além disso, é provável que as espécies de Leishmania tenham influência nas respostas terapêuticas. OBJETIVOS: Avaliar e comparar a eficácia e a segurança dos esquemas de tratamento na LTA, ocasionada por Leishmania (Viannia) guyanensis. MÉTODOS: 185 pacientes foram selecionados, conforme critérios de elegibilidade, e distribuídos, aleatoriamente, em 3 grupos - 2 com 74 enfermos e outro com 37 - que receberam, respectivamente, antimoniato de meglumina, isotionato de pentamidina e anfotericina B em doses, períodos e vias de administração padronizados. Os enfermos foram reexaminados um, dois e seis meses após o final dos tratamentos. RESULTADOS: Não houve diferença entre os grupos terapêuticos em relação ao sexo, idade, número ou local das lesões. A análise por intenção de tratar (ITT) mostrou eficácias de 58,1 por cento para a pentamidina e 55,5 por cento para o antimoniato (p=0,857). O grupo da anfotericina B foi analisado separadamente, pois 28 (75,7 por cento) pacientes negaram-se a continuar no estudo após a randomização. Eventos adversos leves ou moderados foram relatados por 74 (40 por cento) pacientes, principalmente artralgia (20,3 por cento), para o grupo do antimoniato, e dor (35,1 por cento) ou enduração (10,8 por cento) no local das injeções para a pentamidina. CONCLUSÕES: A pentamidina tem eficácia similar ao antimonial pentavalente para o tratamento da LTA ocasionada por L. guyanensis. Face aos baixos resultados de eficácia apresentados por ambas as drogas, necessita-se, com urgência, investigar novas opções terapêuticas para esta enfermidade.

FUNDAMENTALS: American tegumentary leishmaniasis (ATL) treatment remains a challenge, since most available drugs are injectable and only a small number of comparative, randomized clinical trials have been performed to support their use. Moreover, treatment outcome may depend on the causative species of Leishmania. OBJECTIVES: To evaluate and compare the efficacy and tolerability of meglumine antimoniate, pentamidine isethionate, and amphotericin B in the treatment of ATL caused by Leishmania (Viannia) guyanensis. METHODS: 185 patients were selected according to the eligibility criteria and randomly allocated into three groups - two groups with 74 patients each, and one group with 37 patients, which underwent meglumine, pentamidine and amphotericin B treatment, respectively. Doses, mode of administration and time periods of treatment followed the current recommendations for each drug. Patients were re-examined one, two and six months after completion of treatment. RESULTS: No differences were observed among the therapeutic groups in relation to gender, age, number or site of lesions. Intention-to-treat (ITT) analysis showed efficacy of 58.1 percent for pentamidine and 55.5 percent for meglumine (p=0.857). The amphotericin B group was analyzed separately, since 28 patients (75.7 percent) in this group refused to continue participating in the study. Mild or moderate adverse effects were reported by 74 (40 percent) patients, especially arthralgia (20.3 percent) in the meglumine group, and pain (35.1 percent) or induration (10.8 percent) at the site of injection in the pentamidine group. CONCLUSION: Pentamidine and meglumine show similar efficacy in the treatment of ATL caused by L. guyanensis. Given the low efficacy of both drugs, there is an urgent need for new therapeutical approaches.

Pentamidine sensitizes leukemia K562 cells to TRAIL-induced apoptosis / 中国癌症杂志

Background and purpose:Tumor necrosis factor-related apoptosis inducing ligand(TRAIL)is a successful clinical anti-tumor agent.However,not all tumor cells are sensitive to TRAIL-mediated apoptosis.In this study,we examined the TRAIL-induced apoptosis after pretreatment with pentamidine in K562 cells.Methods:When K562 cells were pretreated with pentamidine followed by TRAIL,apoptosis of cells was analyzed by cellular morphology via viewing live cells under a light microscope and annexin V-FITC/propidium iodine FACS.Western blot was performed to examine the cleavage of caspase-3,-8 and poly(ADP-ribose)polymerase(PARR)and protein levels of X-linked inhibitor of apoptosis protein(XIAP).Results:Apoptotic cell death occurred and cleavage of caspase-3,-8 and PARR appeared when K562 cells were pretreated with 10?g/ml of pentamidine followed by 200 ng/ml of TRAIL.In addition,pentamidine decreased protein levels of XIAP.Conclusions:Combined treatment with pentamidine and TRAIL may become a new strategy for cancer therapy.